7.1.0.4

* agent: fast queue rotation does not requiring the current server to be online

* update plan

* update plan and rfc

* corrections

* update plan

* implementation

* test

* refactor

* test switching notificaitons

* rename

* fix, refactor

* fix possible crash

* simplify

* refactor

* simplify

* refactor

* simplify

* order, avoid re-reading connection

---------

Co-authored-by: Evgeny @ SimpleX Chat <259188159+evgeny-simplex@users.noreply.github.com>

.github/workflows/build.yml

@@ -24,6 +24,8 @@ jobs:
       - name: Clone project
         if: startsWith(github.ref, 'refs/tags/v')
         uses: actions/checkout@v3
+        with:
+          submodules: recursive
 
       - name: Build changelog
         id: build_changelog
@@ -114,6 +116,8 @@ jobs:
       - name: Clone project
         if: matrix.should_run == true
         uses: actions/checkout@v3
+        with:
+          submodules: recursive
 
       - name: Set up Docker Buildx
         if: matrix.should_run == true

.github/workflows/docker-image.yml

@@ -20,6 +20,8 @@ jobs:
     steps:
       - name: Clone project
         uses: actions/checkout@v4
+        with:
+          submodules: recursive
 
       - name: Log in to Docker Hub
         uses: simplex-chat/docker-login-action@v3

.github/workflows/reproduce-schedule.yml

@@ -11,6 +11,8 @@ jobs:
     steps:
       - name: Checkout code
         uses: actions/checkout@v3
+        with:
+          submodules: recursive
 
       - name: Get latest release
         shell: bash

.gitmodules

@@ -0,0 +1,6 @@
+[submodule "cbits/libbbs"]
+	path = cbits/libbbs
+	url = https://github.com/simplex-chat/libbbs.git
+[submodule "cbits/blst"]
+	path = cbits/blst
+	url = https://github.com/supranational/blst.git

apps/xftp-server/static/xftp-web-bundle/crypto.worker.js

@@ -619,7 +619,6 @@ async function handleEncrypt(id, data, fileName) {
   const digest = sha512Streaming([encData], (done) => {
     self.postMessage({ id, type: "progress", done: source.length + done, total });
   }, encDataLen);
-  console.log(`[WORKER-DBG] encrypt: encData.len=${encData.length} digest=${_whex(digest, 64)} chunkSizes=[${chunkSizes.join(",")}]`);
   const dir = await getSessionDir();
   const fileHandle = await dir.getFileHandle("upload.bin", { create: true });
   const writeHandle = await fileHandle.createSyncAccessHandle();
@@ -643,9 +642,7 @@ function handleReadChunk(id, offset, size) {
 }
 async function handleDecryptAndStore(id, dhSecret, nonce, body, chunkDigest, chunkNo) {
   const bodyArr = new Uint8Array(body);
-  console.log(`[WORKER-DBG] store chunk=${chunkNo} body.len=${bodyArr.length} nonce=${_whex(nonce, 24)} dhSecret=${_whex(dhSecret)} digest=${_whex(chunkDigest, 32)} body[0..8]=${_whex(bodyArr)} body[-8..]=${_whex(bodyArr.slice(-8))}`);
   const decrypted = decryptReceivedChunk(dhSecret, nonce, bodyArr, chunkDigest);
-  console.log(`[WORKER-DBG] decrypted chunk=${chunkNo} len=${decrypted.length} [0..8]=${_whex(decrypted)} [-8..]=${_whex(decrypted.slice(-8))}`);
   if (useMemory) {
     memoryChunks.set(chunkNo, decrypted);
     self.postMessage({ id, type: "stored" });
@@ -660,7 +657,6 @@ async function handleDecryptAndStore(id, dhSecret, nonce, body, chunkDigest, chu
   currentDownloadOffset += decrypted.length;
   chunkMeta.set(chunkNo, { offset, size: decrypted.length });
   const written = downloadWriteHandle.write(decrypted, { at: offset });
-  console.log(`[WORKER-DBG] OPFS write chunk=${chunkNo} offset=${offset} size=${decrypted.length} written=${written}`);
   if (written !== decrypted.length) {
     console.warn(`[WORKER] OPFS write failed chunk=${chunkNo}: ${written}/${decrypted.length}, falling back to in-memory storage`);
     for (const [cn, meta] of chunkMeta.entries()) {
@@ -684,23 +680,16 @@ async function handleDecryptAndStore(id, dhSecret, nonce, body, chunkDigest, chu
     return;
   }
   downloadWriteHandle.flush();
-  const verifyBuf = new Uint8Array(Math.min(8, decrypted.length));
-  downloadWriteHandle.read(verifyBuf, { at: offset });
-  const verifyEnd = new Uint8Array(Math.min(8, decrypted.length));
-  downloadWriteHandle.read(verifyEnd, { at: offset + decrypted.length - verifyEnd.length });
-  console.log(`[WORKER-DBG] OPFS verify chunk=${chunkNo} readBack[0..8]=${_whex(verifyBuf)} readBack[-8..]=${_whex(verifyEnd)} expected[0..8]=${_whex(decrypted)} expected[-8..]=${_whex(decrypted.slice(-8))}`);
   self.postMessage({ id, type: "stored" });
 }
 async function handleVerifyAndDecrypt(id, size, digest, key, nonce) {
-  console.log(`[WORKER-DBG] verify: expectedSize=${size} expectedDigest=${_whex(digest, 64)} useMemory=${useMemory} chunkMeta.size=${chunkMeta.size} memoryChunks.size=${memoryChunks.size}`);
   const chunks = [];
   let totalSize = 0;
   const total = size * 3;
   let done = 0;
   if (useMemory) {
     const sorted = [...memoryChunks.entries()].sort((a, b) => a[0] - b[0]);
-    for (const [chunkNo, data] of sorted) {
-      console.log(`[WORKER-DBG] verify memory chunk=${chunkNo} size=${data.length}`);
+    for (const [, data] of sorted) {
       chunks.push(data);
       totalSize += data.length;
       done += data.length;
@@ -715,12 +704,10 @@ async function handleVerifyAndDecrypt(id, size, digest, key, nonce) {
     const dir = await getSessionDir();
     const fileHandle = await dir.getFileHandle("download.bin");
     const readHandle = await fileHandle.createSyncAccessHandle();
-    console.log(`[WORKER-DBG] verify: OPFS file size=${readHandle.getSize()}`);
     const sortedEntries = [...chunkMeta.entries()].sort((a, b) => a[0] - b[0]);
-    for (const [chunkNo, meta] of sortedEntries) {
+    for (const [, meta] of sortedEntries) {
       const buf = new Uint8Array(meta.size);
-      const bytesRead = readHandle.read(buf, { at: meta.offset });
-      console.log(`[WORKER-DBG] verify read chunk=${chunkNo} offset=${meta.offset} size=${meta.size} bytesRead=${bytesRead} [0..8]=${_whex(buf)} [-8..]=${_whex(buf.slice(-8))}`);
+      readHandle.read(buf, { at: meta.offset });
       chunks.push(buf);
       totalSize += meta.size;
       done += meta.size;
@@ -745,20 +732,9 @@ async function handleVerifyAndDecrypt(id, size, digest, key, nonce) {
   }
   const actualDigest = r.crypto_hash_sha512_final(state);
   if (!digestEqual(actualDigest, digest)) {
-    console.error(`[WORKER-DBG] DIGEST MISMATCH: expected=${_whex(digest, 64)} actual=${_whex(actualDigest, 64)} chunks=${chunks.length} totalSize=${totalSize}`);
-    const state2 = r.crypto_hash_sha512_init();
-    for (let i = 0; i < chunks.length; i++) {
-      const chunk = chunks[i];
-      for (let off = 0; off < chunk.length; off += hashSEG) {
-        r.crypto_hash_sha512_update(state2, chunk.subarray(off, Math.min(off + hashSEG, chunk.length)));
-      }
-      const chunkDigest = sha512Streaming([chunk]);
-      console.error(`[WORKER-DBG] chunk[${i}] size=${chunk.length} sha512=${_whex(chunkDigest, 32)}… [0..8]=${_whex(chunk)} [-8..]=${_whex(chunk.slice(-8))}`);
-    }
     self.postMessage({ id, type: "error", message: "File digest mismatch" });
     return;
   }
-  console.log(`[WORKER-DBG] verify: digest OK`);
   const result = decryptChunks(BigInt(size), chunks, key, nonce, (d) => {
     self.postMessage({ id, type: "progress", done: size * 2 + d, total });
   });

apps/xftp-server/static/xftp-web-bundle/index.js

@@ -334,11 +334,6 @@ class WorkerBackend {
     const nonceCopy = new Uint8Array(nonce);
     const digestCopy = new Uint8Array(digest);
     const buf = this.toTransferable(body);
-    const hex = (b, n = 8) => {
-      const u = b instanceof ArrayBuffer ? new Uint8Array(b) : b;
-      return Array.from(u.slice(0, n)).map((x) => x.toString(16).padStart(2, "0")).join("");
-    };
-    console.log(`[BACKEND-DBG] chunk=${chunkNo} body.len=${body.length} body.byteOff=${body.byteOffset} buf.byteLen=${buf.byteLength} nonce=${hex(nonceCopy, 24)} dhSecret=${hex(dhSecretCopy)} digest=${hex(digestCopy, 32)} buf[0..8]=${hex(buf)} body[-8..]=${hex(body.slice(-8))}`);
     await this.send(
       { type: "decryptAndStoreChunk", dhSecret: dhSecretCopy, nonce: nonceCopy, body: buf, chunkDigest: digestCopy, chunkNo },
       [buf]
@@ -10913,14 +10908,12 @@ async function sendXFTPCommandOnce(client, privateKey, entityId, cmdBytes, chunk
   const block = encodeAuthTransmission(client.sessionId, corrId, entityId, cmdBytes, privateKey);
   const reqBody = chunkData ? concatBytes$1(block, chunkData) : block;
   const fullResp = await client.transport.post(reqBody);
-  console.log(`[XFTP-DBG] sendOnce: fullResp.length=${fullResp.length} entityId=${_hex(entityId)} cmdTag=${cmdBytes[0]}`);
   if (fullResp.length < XFTP_BLOCK_SIZE) {
     console.error("[XFTP] Response too short: %d bytes (expected >= %d)", fullResp.length, XFTP_BLOCK_SIZE);
     throw new Error("Server response too short");
   }
   const respBlock = fullResp.subarray(0, XFTP_BLOCK_SIZE);
   const body = fullResp.subarray(XFTP_BLOCK_SIZE);
-  console.log(`[XFTP-DBG] sendOnce: body.length=${body.length} body.byteOffset=${body.byteOffset} body.buffer.byteLength=${body.buffer.byteLength}`);
   const raw = blockUnpad(respBlock);
   if (raw.length < 20) {
     const text = new TextDecoder().decode(raw);
@@ -10939,18 +10932,13 @@ async function sendXFTPCommandOnce(client, privateKey, entityId, cmdBytes, chunk
   }
   return { response, body };
 }
-function _hex(b, n = 8) {
-  return Array.from(b.slice(0, n)).map((x) => x.toString(16).padStart(2, "0")).join("");
-}
 async function sendXFTPCommand(agent, server, privateKey, entityId, cmdBytes, chunkData, maxRetries = 3) {
   let clientP = getXFTPServerClient(agent, server);
   let client = await clientP;
   for (let attempt = 1; attempt <= maxRetries; attempt++) {
     try {
-      if (attempt > 1) console.log(`[XFTP-DBG] sendCmd: retry attempt=${attempt}/${maxRetries}`);
       return await sendXFTPCommandOnce(client, privateKey, entityId, cmdBytes, chunkData);
     } catch (e) {
-      console.log(`[XFTP-DBG] sendCmd: attempt=${attempt} failed: ${e instanceof Error ? e.message : String(e)} retriable=${isRetriable(e)}`);
       if (!isRetriable(e)) {
         throw categorizeError(e);
       }
@@ -10979,7 +10967,6 @@ async function downloadXFTPChunkRaw(agent, server, rpKey, fId) {
   const { response, body } = await sendXFTPCommand(agent, server, rpKey, fId, cmd);
   if (response.type !== "FRFile") throw new Error("unexpected response: " + response.type);
   const dhSecret = dh(response.rcvDhKey, privateKey);
-  console.log(`[XFTP-DBG] dlChunkRaw: body.length=${body.length} nonce=${_hex(response.nonce, 24)} dhSecret=${_hex(dhSecret)} body[0..8]=${_hex(body)} body[-8..]=${_hex(body.slice(-8))}`);
   return { dhSecret, nonce: response.nonce, body };
 }
 async function downloadXFTPChunk(agent, server, rpKey, fId, digest) {
@@ -11012,7 +10999,6 @@ function encryptFileForUpload(source, fileName) {
   const encSize = BigInt(chunkSizes.reduce((a, b) => a + b, 0));
   const encData = encryptFile(source, fileHdr, key, nonce, fileSize, encSize);
   const digest = sha512Streaming([encData]);
-  console.log(`[AGENT-DBG] encrypt: encData.len=${encData.length} digest=${_dbgHex(digest, 64)} chunkSizes=[${chunkSizes.join(",")}]`);
   return { encData, digest, key, nonce, chunkSizes };
 }
 const DEFAULT_REDIRECT_THRESHOLD = 400;
@@ -11169,9 +11155,7 @@ async function downloadFileRaw(agent, fd, onRawChunk, options) {
   if (err) throw new Error("downloadFileRaw: " + err);
   const { onProgress} = options ?? {};
   if (fd.redirect !== null) {
-    console.log(`[AGENT-DBG] resolving redirect: outer size=${fd.size} chunks=${fd.chunks.length}`);
     fd = await resolveRedirect(agent, fd);
-    console.log(`[AGENT-DBG] resolved: size=${fd.size} chunks=${fd.chunks.length} digest=${Array.from(fd.digest.slice(0, 16)).map((x) => x.toString(16).padStart(2, "0")).join("")}…`);
   }
   const resolvedFd = fd;
   let downloaded = 0;
@@ -11189,7 +11173,6 @@ async function downloadFileRaw(agent, fd, onRawChunk, options) {
       const seed = decodePrivKeyEd25519(replica.replicaKey);
       const kp = ed25519KeyPairFromSeed(seed);
       const raw = await downloadXFTPChunkRaw(agent, server, kp.privateKey, replica.replicaId);
-      console.log(`[AGENT-DBG] chunk=${chunk.chunkNo} body.len=${raw.body.length} expectedChunkSize=${chunk.chunkSize} digest=${_dbgHex(chunk.digest, 32)} body.byteOffset=${raw.body.byteOffset} body.buffer.byteLength=${raw.body.buffer.byteLength}`);
       await onRawChunk({
         chunkNo: chunk.chunkNo,
         dhSecret: raw.dhSecret,

cbits/getentropy_win.c

@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: Apache-2.0
+// getentropy() shim for Windows, where it is absent from the CRT.
+// Follows the POSIX contract: fills `buffer` with `length` random bytes
+// (length must not exceed 256), returns 0 on success or -1 with errno set.
+#ifdef _WIN32
+#include <errno.h>
+#include <stddef.h>
+#include <windows.h>
+#include <bcrypt.h>
+
+int getentropy(void *buffer, size_t length) {
+    if (length > 256) {
+        errno = EIO;
+        return -1;
+    }
+    NTSTATUS status = BCryptGenRandom(NULL, (PUCHAR)buffer, (ULONG)length,
+                                      BCRYPT_USE_SYSTEM_PREFERRED_RNG);
+    if (!BCRYPT_SUCCESS(status)) {
+        errno = EIO;
+        return -1;
+    }
+    return 0;
+}
+#endif

plans/2026-06-01-bbs-bindings.md

@@ -0,0 +1,126 @@
+# BBS+ Bindings for simplexmq
+
+Haskell FFI bindings to libbbs for BBS+ signatures. General-purpose - the module knows nothing about specific applications.
+
+## How BBS+ works
+
+BBS+ signs a fixed list of N messages. Each message is an arbitrary byte array. The signer signs all N messages at once with one signature.
+
+The holder of the signature can then generate a proof that selectively discloses some messages and hides others. The verifier learns the disclosed messages and confirms they were signed by the signer, but learns nothing about the hidden messages. Different proofs from the same signature are unlinkable.
+
+Key constraint: the total number of messages N is fixed at signing time. The verifier must know N. A proof generated from a 3-message signature cannot be verified as a 2-message proof.
+
+## Types
+
+```haskell
+newtype BBSSecretKey = BBSSecretKey ByteString  -- 32 bytes
+newtype BBSPublicKey = BBSPublicKey ByteString  -- 96 bytes (BLS12-381 G2 point)
+newtype BBSSignature = BBSSignature ByteString  -- 80 bytes
+newtype BBSProof = BBSProof ByteString          -- 272 + 32 * numUndisclosed bytes
+newtype BBSHeader = BBSHeader ByteString        -- always-disclosed context (e.g. protocol identifier)
+newtype BBSPresHeader = BBSPresHeader ByteString -- random nonce for proof unlinkability
+```
+
+All newtypes get StrEncoding (base64url), ToJSON/FromJSON (via strToJSON/strParseJSON), Eq, Show.
+
+## Functions
+
+```haskell
+bbsKeyGen :: IO (Either String BBSKeyPair)  -- BBSKeyPair = (BBSPublicKey, BBSSecretKey)
+
+-- pk is derived from sk internally, so it is not a parameter
+bbsSign
+  :: BBSSecretKey
+  -> BBSHeader            -- always-disclosed context
+  -> [ByteString]         -- all N messages
+  -> IO (Either String BBSSignature)
+
+-- C order: pk, signature, header, presentation_header, disclosed_indexes, messages
+bbsProofGen
+  :: BBSPublicKey
+  -> BBSSignature
+  -> BBSHeader            -- must match what was signed
+  -> BBSPresHeader        -- random nonce bound into the proof
+  -> [Int]                -- disclosed indexes (0-based)
+  -> [ByteString]         -- all N messages (needed internally, hidden ones not revealed in proof)
+  -> IO (Either String BBSProof)
+
+-- C order: pk, proof, header, presentation_header, disclosed_indexes, n, messages
+bbsProofVerify
+  :: BBSPublicKey
+  -> BBSProof
+  -> BBSHeader            -- must match what was signed
+  -> BBSPresHeader        -- must match what was used in bbsProofGen
+  -> [Int]                -- disclosed indexes
+  -> Int                  -- total message count N
+  -> [ByteString]         -- disclosed messages only
+  -> IO Bool
+```
+
+## How applications use it
+
+An application defines:
+- A message layout: which index means what
+- Which indexes are disclosed vs hidden
+- How to encode application values as ByteString messages
+
+### Badge example (in simplex-chat, not in this module)
+
+Message layout (always 3 messages):
+- Index 0: master secret (32 random bytes) - HIDDEN
+- Index 1: expiry (UTF-8 encoded timestamp string) - DISCLOSED
+- Index 2: badge type (UTF-8 encoded, e.g. "supporter") - DISCLOSED
+
+Signing (v2, on the server):
+```
+bbsSign sk header [ms, encodeUtf8 "2026-07-31", encodeUtf8 "supporter"]
+```
+
+Proof generation (v2, on the client):
+```
+bbsProofGen pk sig header presHeader [1, 2] [ms, encodeUtf8 "2026-07-31", encodeUtf8 "supporter"]
+```
+
+Proof verification (v1, on the recipient):
+```
+bbsProofVerify pk proof header presHeader 3 [1, 2] [encodeUtf8 "2026-07-31", encodeUtf8 "supporter"]
+```
+
+The recipient only sees the proof, presentationHeader, expiry string, and badge type string. They verify these were signed by the server (pk is hardcoded). They never see the master secret.
+
+Expiry is always present as a string. Monthly badges use a date like `"2026-07-31"`, lifetime badges use `"lifetime"`. BBS+ doesn't interpret the bytes - expiry semantics are the application's responsibility. This keeps the message count fixed at 3 for all badge types.
+
+## libbbs C API mapping
+
+```c
+int bbs_keygen_full(ciphersuite, sk, pk)
+int bbs_sign(ciphersuite, sk, pk, signature, header, header_len, n, messages, message_lens)
+int bbs_proof_gen(ciphersuite, pk, signature, proof, header, header_len, presentation_header, presentation_header_len, disclosed_indexes, disclosed_indexes_len, n, messages, message_lens)
+int bbs_proof_verify(ciphersuite, pk, proof, proof_len, header, header_len, presentation_header, presentation_header_len, disclosed_indexes, disclosed_indexes_len, n, messages, message_lens)
+```
+
+We use `bbs_sha256_ciphersuite`. The header parameter is exposed in all Haskell functions - the application decides what to put there. Tests use `"SimpleX"` as header.
+
+The `presentation_header` parameter is what we call `presentationHeader`.
+
+In `bbs_proof_verify`, the `n` parameter is the total number of messages (not the number of disclosed messages). The `messages` array contains only the disclosed messages, and `disclosed_indexes` maps each to its position in the original message list.
+
+## Build
+
+Submodules in cbits/:
+- `cbits/libbbs` - https://github.com/Fraunhofer-AISEC/libbbs
+- `cbits/blst` - https://github.com/supranational/blst (libbbs dependency)
+
+C sources in cabal: `cbits/blst/src/server.c`, `cbits/blst/build/assembly.S`, libbbs source files.
+Include dirs: `cbits/blst/bindings/`, `cbits/blst/src/`, `cbits/libbbs/include/`, `cbits/libbbs/src/`.
+C flags: `-D__BLST_PORTABLE__` for cross-CPU-generation compatibility.
+
+## Tests
+
+- Keygen produces keys of correct size
+- Sign + proofGen + proofVerify roundtrip succeeds
+- Tampered proof fails verification
+- Tampered disclosed message fails verification
+- Wrong public key fails verification
+- Two proofs from same credential with different nonces both verify
+- Proof size matches expected (272 + 32 * numUndisclosed)

plans/2026-06-27-service-subscriptions-memory-leak.md

@@ -0,0 +1,57 @@
+## Root cause: orphaned `Sub` entries in the service client's `subscriptions` map
+
+**The leak is service-specific and was introduced by PR #1667 "messaging services" (`f0b7a4be`).** A long-lived messaging-service connection accumulates per-queue `Sub` records in its `Client.subscriptions` map that are **never removed** when the associated queues are deleted or unassociated — only the counter is decremented. Over normal queue churn the map grows monotonically for the entire lifetime of the service connection.
+
+### The proof — an asymmetry between two handlers in `serverThread`
+
+Both individual queue subscriptions and service subscriptions store a `Sub` per queue in `Client.subscriptions` (= `clientSubs` for the SMP subscriber thread, wired at `Server.hs:189`). When a queue ends/is deleted, the two paths diverge:
+
+**Individual subscriber — entry IS removed** (`Server.hs:332`, `346`):
+```haskell
+CSAEndSub qId -> atomically (endSub c qId) >>= a unsub_   -- :332
+  ...
+endSub c qId = TM.lookupDelete qId (clientSubs c) >>= (removeWhenNoSubs c $>)  -- :346
+```
+
+**Service subscriber — entry is NOT removed** (`Server.hs:336-340`):
+```haskell
+CSAEndServiceSub qId -> atomically $ do
+  modifyTVar' (clientServiceSubs c) decrease   -- decrements serviceSubsCount
+  modifyTVar' totalServiceSubs decrease        -- decrements global count
+  where decrease = subtractServiceSubs (1, queueIdHash qId)
+  -- never touches (clientSubs c) — the Sub for qId stays forever
+```
+
+### Where the orphaned entries are added (both new in this PR)
+- `Server.hs:1860-1862` — on service subscribe (`SSUB`), one `Sub` inserted per queue that has a pending message.
+- `Server.hs:2039-2043` (`newServiceDeliverySub`) — on **every** `SEND` to a service-associated queue with no existing sub, a `Sub` is inserted into the service client's `subscriptions`. After delivery the thread state resets to `NoSub` (`:2069`) but the map entry remains as a "already delivering" marker (`:1856-1859`).
+
+### Why they leak
+The only places the service client's `subscriptions` map is cleared are:
+- `clientDisconnected` — `swapTVar subscriptions M.empty` (`Server.hs:1097`) — only on disconnect.
+- `CSADecreaseSubs` — `swapTVar (clientSubs c) M.empty` (`Server.hs:343`) — only on full service takeover by another connection.
+- `delQueueAndMsgs` — `TM.lookupDelete entId $ subscriptions clnt` (`Server.hs:2164`) — but `clnt` here is **the recipient deleting its own queue, not the service client**. The service's entry for that queue is reached only via the `CSDeleted → endServiceSub → CSAEndServiceSub` path (`Server.hs:306, 313, 336`), which decrements the counter but leaves the map entry.
+
+**Concrete scenario (fully traced):** Service `S` subscribes (`SSUB`) and stays connected for days. Recipient `R` owns service-associated queue `Q`. A `SEND` to `Q` inserts a `Sub` into `S.subscriptions[Q]` (`:2042`). `R` later deletes `Q` → `delQueueAndMsgs` runs on `R`'s connection, removes `Q` from `R.subscriptions`, decrements counters, enqueues `CSDeleted Q (Just S)` (`:2167`) → `serverThread` runs `CSAEndServiceSub Q` for `S` (`:336`), decrementing `S.serviceSubsCount` but **leaving `S.subscriptions[Q]` in place**. Net: one orphaned `Sub` (record + 2 TVars) per service-associated queue ever deleted/unassociated, never reclaimed until `S` disconnects. The logical counter `serviceSubsCount` correctly drops, so the map size diverges from the counter — making the leak invisible to the existing service-sub metric.
+
+### Verdict
+This is a deterministic, static-provable memory leak — no production logging needed to confirm the existence; the asymmetry between `CSAEndSub` (removes) and `CSAEndServiceSub` (doesn't) is the smoking gun. It is specific to messaging-service certificate clients, which is exactly the population added by the services/certificate PR.
+
+### Secondary findings (lower impact, same PR area, not the primary cause)
+- **`forkClient` register-after-fork race** (`Server.hs:1356-1359`): if the forked action's `finally` delete (`:1358`) runs before the parent's `IM.insert` (`:1359`), a `Weak ThreadId` of a dead thread is left in `endThreads` until disconnect. Pre-existing, tiny per-entry, but exercised far more by the PR's higher END/DELD volume.
+- **Wrong-client counter decrement** (`Server.hs:2166`): `delQueueAndMsgs` decrements `serviceSubsCount` of the *deleting* client, not the service; harmless for non-service deleters (floored at 0) but corrupts accounting if a service deletes its own queue.
+
+---
+
+### Recommended fix (mirror `endSub` in the service path)
+Make `CSAEndServiceSub` also delete the per-queue `Sub` and cancel its delivery thread, exactly as `CSAEndSub`/`endSub` do for individual subscribers. Roughly:
+
+```haskell
+CSAEndServiceSub qId -> do
+  s_ <- atomically $ do
+    modifyTVar' (clientServiceSubs c) decrease
+    modifyTVar' totalServiceSubs decrease
+    TM.lookupDelete qId (clientSubs c) <* removeWhenNoSubs c
+  forM_ unsub_ $ \unsub -> mapM_ unsub s_
+  where decrease = subtractServiceSubs (1, queueIdHash qId)
+```

plans/2026-07-11-service-rpc-implementation.md

@@ -0,0 +1,135 @@
+# Service RPC implementation plan
+
+RFC: [../rfcs/2026-07-11-service-rpc.md](../rfcs/2026-07-11-service-rpc.md)
+
+Depends on: [2026-07-12-address-dr-implementation.md](2026-07-12-address-dr-implementation.md). RPC establishes the double ratchet from the address exactly as address-DR does; this is the RPC layer on top of it.
+
+**Status: implemented and tested in this repo.** Service-side idempotency (single execution by request hash) is deferred. The `simplex-chat` integration is a separate repo.
+
+**Scope.** One request, one response — no continuation, no streaming.
+
+One DR-advertising contact address serves both flows: the owner branches per incoming request on the decrypted inner message — `AgentConnInfoReply` opens a connection (`REQ`), `AgentServiceRequest` answers an RPC (`SREQ`). A request gets exactly one reply, a response or a rejection; both are the single confirming message on the requester's reply queue Q_A, after which the ephemeral reply connection is torn down. Response and rejection are the same operation parameterized by the inner message (`AgentServiceResponse` payload vs `AgentRejection` reason) and outcome (the call returns the payload vs throws an agent error).
+
+## RPC messages
+
+No new outer envelope: the request reuses `AgentContactRequest` (tag `'A'`); the reply reuses `AgentConfirmation` (the only message on Q_A).
+
+Inner `AgentMessage` (ratchet-encrypted, parsed by `parseMessage`), siblings of `AgentConnInfoReply`:
+
+```haskell
+  | AgentServiceRequest (NonEmpty SMPQueueInfo) MsgBody  -- 'A': reply queue Q_A + opaque payload
+  | AgentServiceResponse MsgBody                         -- 'P': response payload (single, terminal)
+  | AgentRejection ByteString                            -- 'J': refusal reason (single, terminal)
+```
+
+`AgentServiceRequest` carries Q_A (as `AgentConnInfoReply` does); its constructor is the only thing that distinguishes `REQ` from `SREQ`. Delivery `msgType`: `AM_SRV_RESP` routes to `sendConfirmation` (the reply is the confirming first message on Q_A). `AM_SRV_REQ` is never stored — the request is sent synchronously inside `joinConnSrv'` via `sendInvitation`, so its arms in the delivery worker are unreachable and assert (`logError`).
+
+## Ratchet establishment — reuse of the address-DR flow
+
+`joinConnSrv'` takes `mkInner :: SMPQueueInfo -> AgentMessage`; `joinConnSrv` is the one-line wrapper passing `AgentConnInfoReply`. `sendServiceRequest'` passes `AgentServiceRequest`.
+
+**Request (client).** `serviceRequest_` fails fast with `A_SERVICE ASENotDRAddress` if the address carries no ratchet keys, then creates the client connection via `newConnToJoin` with `serviceRequestExpiresAt = Just (now + reqTimeout)` (the persisted per-request deadline), registers a one-shot `TMVar` in `serviceRequests`, sends the request, and blocks on the `TMVar` up to `reqTimeout`. The connection is `RcvConnection` (Q_A) with the send ratchet.
+
+**Request (service).** `smpContactRequest` decrypts `encConnInfo` and branches on the inner message; both branches call the same `storeInvitation` → `conn_invitations`, differing only in the kind column and event:
+
+- `AgentConnInfoReply` → `REQ` (`service_request = 0`).
+- `AgentServiceRequest _ payload` → `SREQ invId payload` (`service_request = 1`).
+
+Before storing, it **deduplicates** by the sender's ratchet-key hash (`checkRatchetKeyHashExists`/`addProcessedRatchetKeyHash`, the mechanism `newRatchetKey` uses): a redelivered/retried request reuses the same Q_A and the same `e2eSndParams`, so the hash matches and the duplicate is dropped — one invitation and one `REQ`/`SREQ` per request. Receive-time establishment on unauthenticated input — the address-DR abuse bound applies.
+
+**The reply (service).** `prepareReply` fetches the invitation, enforces the kind (`CMD PROHIBITED` on the wrong one), and rejects a stale request (`A_SERVICE ASETimeout` + delete) older than `serviceResponseTimeout`; then `newConnToAccept` + `startJoinInvitationDR` build the one-directional `SndQueue` to Q_A (no reply queue back), and `storeConfirmation` queues the inner message. `sendReplySync` secures Q_A, submits the message, and deletes the connection with wait-for-delivery — **deleting the connection on failure too** (`catchAllErrors`), so a failed secure/submit does not orphan it. `sendServiceReplyAsync` defers secure+deliver+delete to the `ICReplyDel` command (retried, survives a down server). `sendServiceReply`/`Async` and `replyRequest_` return the reply `ConnId` so the caller can correlate the `SENT` event on that throwaway connection.
+
+**The response (client).** The single `AgentConfirmation` on Q_A reaches `processConnInfo` (the `RcvConnection … New` branch). Dispatch is gated on `serviceRequestExpiresAt` and the kinds are mutually exclusive:
+
+- `AgentConnInfoReply` **only when `isNothing serviceRequestExpiresAt`** (a contact connection) → `processConf`.
+- `AgentServiceResponse` only when `isJust` → the request `TMVar` gets `Right payload`.
+- `AgentRejection` when `isJust` → `Left (A_SERVICE (ASERejected reason))`; when `isNothing` → contact `RJCT`.
+- anything else → `prohibited`.
+
+The `isNothing` guard on `AgentConnInfoReply` is a security boundary: without it a malicious service could send `AgentConnInfoReply` on an RPC reply queue and drive it into the contact-`CONF` path. `dispatchServiceReply` puts the result into the `serviceRequests` `TMVar`; a reply with no pending request (e.g. post-restart) is `ERR (A_SERVICE ASENoPendingRequest)`.
+
+## Rejection
+
+A rejection is `AgentRejection reason` — the same single confirming message on Q_A as a response.
+
+- **Kind guard.** `rejectContact` only on a contact invitation, `rejectServiceRequest`/`sendServiceReply` only on a request; wrong kind is `CMD PROHIBITED`. `rejectRequest_` enforces the kind **even on a `Nothing` (silent-drop) reject** — it fetches the invitation and checks before deleting, so `rejectContact … Nothing` cannot delete a service request (or vice versa).
+- `reject*` take `Maybe ByteString`: `Nothing` → delete the invitation, send nothing (the requester times out); `Just reason` → the reply path with `AgentRejection`.
+- Requester side: `AgentRejection` on a contact reply queue → `RJCT`; on an RPC reply queue → a thrown `A_SERVICE (ASERejected reason)`.
+
+## Reply connections and cleanup
+
+No reply-queue table and no new connection type.
+
+- **Requester reply queue** (`RcvConnection` on Q_A): `connections.service_request_expires_at` is non-null only here; it is the persisted request deadline, used both to gate CONF dispatch and to reap the connection. In-memory routing is `serviceRequests :: TMap ConnId (TMVar (Either AgentErrorType MsgBody))`.
+- **Timeout race.** The async `JOIN` worker holds `withConnLock c connId` around `joinConnSrv'`, and `serviceRequest_`'s cleanup holds the same lock around `TM.delete` + `deleteConnectionAsync'`. This serializes the send with the timeout teardown, so a timing-out call cannot delete the connection mid-send; after cleanup the worker's re-check of `serviceRequests` finds nothing and skips.
+- **Service reply connection** (`SndConnection` to Q_A): ephemeral — created, sends the one reply, deleted with wait-for-delivery in the same operation.
+- **Cleanup** (`cleanupManager`, `deleteExpiredServiceReqs`): `deleteExpiredServiceRequests` reaps unanswered `conn_invitations` (service side) older than `serviceResponseTimeout`; `getExpiredServiceConns` (`service_request_expires_at < now`) → `deleteConnectionsAsync'` reaps orphaned requester reply queues.
+
+## Database schema
+
+`M20260712_address_dr_rpc` (SQLite + PostgreSQL) creates `address_ratchet_keys` (address-DR) and adds:
+
+```sql
+ALTER TABLE conn_invitations ADD COLUMN service_request INTEGER NOT NULL DEFAULT 0; -- service side: 1 = RPC request
+ALTER TABLE connections ADD COLUMN service_request_expires_at TEXT;                 -- client side: request deadline; gating + cleanup (nullable)
+```
+
+The down migration drops the columns then the table/index. Schema dump tests pass (up, down, STRICT).
+
+## Agent API — `Simplex.Messaging.Agent`
+
+```haskell
+-- service: send the one response, return the reply ConnId, then tear the reply connection down.
+sendServiceReply      :: AgentClient -> NetworkRequestMode -> UserId -> InvitationId -> MsgBody -> AE ConnId
+sendServiceReplyAsync :: AgentClient -> ACorrId -> UserId -> InvitationId -> MsgBody -> AE ConnId
+
+-- refuse a request (Just reason = AgentRejection; Nothing = silent drop). PROHIBITED on wrong kind.
+rejectServiceRequest      :: AgentClient -> NetworkRequestMode -> UserId -> InvitationId -> Maybe ByteString -> AE ()
+rejectServiceRequestAsync :: AgentClient -> ACorrId -> UserId -> InvitationId -> Maybe ByteString -> AE ()
+rejectContact      :: AgentClient -> NetworkRequestMode -> UserId -> ConfirmationId -> Maybe ByteString -> AE ()
+rejectContactAsync :: AgentClient -> ACorrId -> UserId -> ConfirmationId -> Maybe ByteString -> AE ()
+
+-- client: establish the ratchet from the address, send the request, block on the reply TMVar up to the timeout
+-- (Nothing = serviceRequestTimeout; Just t overrides per request), returning the payload. Sync fails fast if the
+-- server is down; async enqueues a retried JOIN command that survives an outage.
+sendServiceRequest      :: AgentClient -> NetworkRequestMode -> UserId -> ConnectionRequestUri 'CMContact -> Maybe NominalDiffTime -> MsgBody -> AE MsgBody
+sendServiceRequestAsync :: AgentClient -> UserId -> ConnectionRequestUri 'CMContact -> Maybe NominalDiffTime -> MsgBody -> AE MsgBody
+```
+
+Both client calls share `serviceRequest_`; the async `JOIN` worker branches on the `JRServiceReq` command to send `AgentServiceRequest`. The call blocks on the `TMVar` and returns synchronously — no events, no correlation for the app.
+
+Events (`AEvent`, entity is the address connection):
+
+```haskell
+SREQ :: InvitationId -> MsgBody -> AEvent AEConn  -- payload = the request; mirrors REQ.
+RJCT :: ConnInfo -> AEvent AEConn                 -- contact-request rejection reason.
+```
+
+Errors (`SMPAgentError`):
+
+```haskell
+| A_SERVICE {serviceError :: AgentServiceError}
+
+data AgentServiceError
+  = ASERejected {rejectReason :: Text}  -- service refused (Text: JSON-serializable, UTF-8-decoded from the reason bytes)
+  | ASETimeout                          -- no reply within the timeout
+  | ASENoPendingRequest                 -- a reply arrived with no pending request (e.g. post-restart)
+  | ASENotDRAddress                     -- the target address advertises no ratchet keys (fail fast, no send)
+```
+
+Config (`AgentConfig`): `serviceRequestTimeout` (30 s, client wait, overridable per request) and `serviceResponseTimeout` (180 s, service reply window and cleanup TTL; must exceed `serviceRequestTimeout`).
+
+## Idempotency (deferred)
+
+Not built. When built, the service will key a request by hash and cache the one response for a retention period, answering a repeat from storage without reaching the bot — single execution over at-least-once delivery, with its own tables.
+
+## Tests
+
+In `FunctionalAPITests` (plus the encoding roundtrip in `ConnectionRequestTests`), passing with `-O0`:
+
+- Request → one response, sync (`sendServiceReply`) and async (`sendServiceReplyAsync`).
+- Request → rejection (`rejectServiceRequest (Just reason)` → thrown `A_SERVICE (ASERejected …)`).
+- Resilience: `server down → send → up → receive → down → reply → up → receive response`.
+- No regression: the contact rejection and DR-join suites still pass.
+
+The `simplex-chat` end-to-end tests (happy path, drop-when-off, non-DR fail-fast) live in that repo.

plans/2026-07-12-address-dr-implementation.md

@@ -0,0 +1,279 @@
+# Establishing the double ratchet from address data - implementation plan
+
+RFC: [../rfcs/2026-07-12-address-pqdr-keys.md](../rfcs/2026-07-12-address-pqdr-keys.md)
+
+All references are to the current tree. Names of new constructors, fields, tables and functions are provisional.
+
+Goal: a contact address advertises the owner's X3DH parameters in link data; a requester establishes the double ratchet in its first message, so that message and the profile in it are under the ratchet with post-quantum protection. The change reuses the invitation/confirmation machinery, with the requester in the joiner role and the owner in the initiator role - opposite to today's contact flow, but every message and code path below is reused.
+
+Version: `addressDRVersion = VersionSMPA 8`, a plain agent-layer bump; `currentSMPAgentVersion` goes 7 → 8 (Agent/Protocol.hs:317-324). It gates the `AgentConfirmation.ratchetKeyId` field and the DR-from-address behavior. The receive-at-address path relies on ratchet-on-confirmation, already present since `ratchetOnConfSMPAgentVersion = 7` (Agent/Protocol.hs:317), so there is no cross-layer version dependency; the SMP and e2e-encryption versions are unchanged.
+
+Scope of this change: the **synchronous** DR handshake in join, gated on the address advertising `ratchetKeys`. `joinConnection`/`joinConn`/`joinConnSrv` gain an optional `Maybe AddressRatchetKeys` (the advertised `RcvE2ERatchetParamsUri` + `ratchetKeyId`), passed in from the link data the caller fetched at plan time (`LGET`); present → DR path (R2'/R3'), absent → the classic `AgentInvitation`. Chat wires that argument later (a chat change); the agent supports it now and tests pass it directly. Making the send **async** (worker retry, a "connecting" UX, the `CreatedConnLink` LGET-gate) is **deferred** - kept below under "Deferred" as future work, not part of this change.
+
+### Implementation status (as built; `lib:simplexmq` compiles)
+
+**Done** (compiles): version bump; `RatchetKeyId`/`AddressRatchetKeys` types + `Encoding`, `UserContactData.ratchetKeys` (appended, backward-compatible); `AgentConfirmation.ratchetKeyId` (version-gated encode/decode); `ContactRequest`/`DRRequest` sum with tagged `Encoding` + `cr_invitation` `ToField`/`FromField` (legacy-URI fallback); `address_ratchet_keys` table + `createAddressRatchetKeys`/`getAddressRatchetKeys` (SQLite + Postgres migrations `M20260712_address_dr`); join threading (`Maybe AddressRatchetKeys`); requester R2'/R3' (`joinAddressDR` + `sendConfirmationToAddress`); owner O1' dispatch, O2' `smpAddressConfirmation`, O3' (`acceptContact'` continue-ratchet branch), all three `connReq` readers (`acceptContact'`, `acceptContactAsync'` → `CMD PROHIBITED` for DR, `newConnToAccept` → shell from `drAgentVersion`/`drPQSupport`); requester R5' (`smpConfirmation` `RcvConnection … Nothing` branch, guarded on a ratchet existing); address-creation bundle generation (`mkAddressRatchetKeys`) wired into `createConnectionForLink'` (`IKUsePQ`-for-`SCMContact` prohibition lifted there).
+
+**Deltas from the plan discovered while building:**
+- **R5' emits `CONF` and reuses the allow step** (not auto-complete). The DR requester is a `RcvConnection` receiving the owner's reply - the same position as the classic contact requester, which goes `CONF` → `allowConnection'` → `connectReplyQueues` (msg 3). R5' mirrors that (differing only in that the ratchet already exists, so it `getRatchet` + `rcDecrypt` instead of building it), so the app supplies `ownConnInfo` for msg 3 at allow, exactly as today. No new storage.
+- **`DRRequest` carries `drAgentVersion` + `drPQSupport`** (Part 3): the sync accept creates the connection shell via `newConnToAccept`→`newConnToJoin` before O3', and there is no URI to derive the version/PQ from.
+- `cr_invitation` serialization is downgrade-safe: `CRInvitation` keeps the legacy URI (`strEncode`, byte-identical to before), so an older agent still reads classic invitations; `CRConfirmation` is JSON (`DRRequest` has manual `ToJSON`/`FromJSON`), told apart on read by the leading `{` (a URI never starts with it). JSON keeps `DRRequest` extensible. `SMPQueueInfo` gained a base64 `StrEncoding` + JSON (it only had `Encoding`) so it can sit in the JSON.
+- **DR is opt-in per address**: `createConnectionForLink'`/`createConnectionForLink` gain a `Maybe InitialKeys` DR parameter (separate from the existing connection-PQ `InitialKeys`) - `Nothing` = no DR (old behavior, existing callers), `Just ik` = advertise the bundle with `ik`. The `IKUsePQ`-for-`SCMContact` prohibition stays on the connection-PQ parameter and is lifted only for the DR bundle.
+
+**Test-matrix consequence of the version bump:** `currentSMPAgentVersion` 7 → 8 moves the version-matrix "prev" (`current − 1`) from v6 to v7. v7 ≥ `ratchetOnConfSMPAgentVersion (7)`, so a joiner/acceptor at "prev" now secures the send queue on confirmation - the `sqSecured` expectation for the prev variants in `testMatrix2`/`testMatrix2Stress`/`testBasicMatrix2` flips `False → True`. (Standard version-bump maintenance; the pre-`ratchetOnConf` unsecured path is now two versions back and no longer exercised by these matrices.)
+
+**Not yet done:** rotation (`rotateRatchetKeys`, Part 4), cleanup step (Part 4), the app-driven `LSET` upgrade API (Part 5), wiring the DR parameter into the non-prepared-link `newRcvConnSrv` path, DR-specific tests (Part 6), regenerating `agent_schema.sql` if a schema-consistency test requires it, and chat wiring (deferred by design).
+
+## Part 1 - the current contact-address handshake, step by step
+
+Requester Alice connects to owner Bob's contact address. Q_A is Alice's receive queue (Bob to Alice), Q_B is Bob's receive queue (Alice to Bob).
+
+Requester side, in `joinConnSrv … CRContactUri` (Agent.hs:1398-1428):
+
+- R1. `compatibleContactUri` (Agent.hs:1370) - version check, yields the address queue `SMPQueueInfo`.
+- R2. `mkJoinInvitation` (Agent.hs:1411): creates or reuses the receive queue Q_A; `getRatchetX3dhKeys` or `generateRcvE2EParams` produces Alice's Rcv X3DH parameters, stored by `createRatchetX3dhKeys` (Agent.hs:1424); builds `cReq = CRInvitationUri crData aliceRcvParams` (Agent.hs:1426).
+- R3. `sendInvitation` (Agent.hs:1408; Agent/Client.hs:1924-1934): sends `AgentInvitation {connReq = cReq, connInfo = aliceProfile}` to the address queue, per-queue encrypted with a fresh ephemeral key by `agentCbEncryptOnce` (Agent/Client.hs:1929-1934), unauthenticated. **`connInfo` (Alice's profile) is under the per-queue X25519 layer only - the gap this plan closes.**
+
+Owner side, receiving on the contact address:
+
+- O1. `processClientMsg` dispatch (Agent.hs:3185): state `(Nothing, Just e2ePubKey)`, `(PHEmpty, AgentInvitation {connReq, connInfo})` -> `smpInvitation` (Agent.hs:3186).
+- O2. `smpInvitation` (Agent.hs:3610): stores an `Invitation`, emits `REQ` with Alice's `connInfo`.
+- O3. `acceptContact'` (Agent.hs:1477): `getInvitation`, then `joinConn` with Alice's `connReq` (Agent.hs:1480).
+- O4. `joinConnSrv … CRInvitationUri` (Agent.hs:1383) -> `startJoinInvitation` (Agent.hs:1395).
+- O5. `startJoinInvitation` (Agent.hs:1310-1350): creates Bob's send queue to Q_A (`newSndQueue`, Agent.hs:1335); `createRatchet_` (Agent.hs:1343-1350) runs `generateSndE2EParams`, `pqX3dhSnd` against Alice's Rcv parameters, `initSndRatchet`, `createSndRatchet`.
+- O6. `secureConfirmQueue` (Agent.hs:1396, 3747-3765): `agentSecureSndQueue` secures Q_A with `SKEY` (Agent.hs:3749); `mkAgentConfirmation` (Agent.hs:3780-3785) calls `createReplyQueue` to create Bob's receive queue Q_B and returns `AgentConnInfoReply (Q_B :| []) bobInfo`; `mkConfirmation` ratchet-encrypts it and wraps `AgentConfirmation {e2eEncryption_ = Just bobSndParams, encConnInfo}`; `sendConfirmation` sends it to Q_A. This is confirmation #1.
+
+Requester side, receiving confirmation #1 on Q_A:
+
+- R4. dispatch (Agent.hs:3181-3183): state `(Nothing, Just e2ePubKey)`, `AgentConfirmation` -> `smpConfirmation`.
+- R5. `smpConfirmation`, initiating-party branch `RcvConnection … Just e2eEncryption` (Agent.hs:3405-3444): `getRatchetX3dhKeys`, `pqX3dhRcv` (Agent.hs:3408), `initRcvRatchet` (Agent.hs:3411), `createRatchet` (Agent.hs:3436), `setRcvQueueConfirmedE2E` (Agent.hs:3440); decrypts `AgentConnInfoReply` (Agent.hs:3420); `processConf` emits `CONF` (Agent.hs:3444).
+- R6. `allowConnection'` (Agent.hs:1467-1474): `acceptConfirmation`, then `ICAllowSecure` secures Q_A with Bob's sender key.
+- R7. `connectReplyQueues` (Agent.hs:3724-3737): `upgradeConn` creates Alice's send queue to Q_B; `agentSecureSndQueue` secures Q_B; `enqueueConfirmation … Nothing` (Agent.hs:3733) stores `AgentConnInfo aliceInfo` and sends `AgentConfirmation {e2eEncryption_ = Nothing, encConnInfo}` to Q_B. This is confirmation #2.
+
+Owner side, receiving confirmation #2 on Q_B:
+
+- O7. dispatch (Agent.hs:3182): `AgentConfirmation` -> `smpConfirmation`.
+- O8. `smpConfirmation`, accepting-party branch `DuplexConnection … Nothing` (Agent.hs:3447-3462): `agentRatchetDecrypt` with the established ratchet; `AgentConnInfo` -> `INFO` (Agent.hs:3452); `ICDuplexSecure` or `CON`.
+
+Completion is direct `CON` on `senderCanSecure` (SKEY) messaging-mode queues (the sender on `AgentConnInfo`, Agent.hs:2252; the receiver with no `senderKey`, Agent.hs:3459-3461); the separate `HELLO` via `helloMsg` (Agent.hs:3466) is the older non-`senderCanSecure` (duplexHandshake v2, in-band-securing) path.
+
+## Part 2 - the DR-from-address handshake, mapped to Part 1
+
+The address advertises Bob's Rcv X3DH parameters in link data (Part 3). Alice, when the address advertises them and versions are compatible, takes the joiner role; Bob takes the initiator role.
+
+Requester side - a new branch in `joinConnSrv … CRContactUri`, taken when the passed `Maybe AddressRatchetKeys` is present (the caller's plan-time `LGET`):
+
+- R2'. Replaces R2/R3. Read the passed bundle - `ratchetKeyId` and `e2eParams :: RcvE2ERatchetParamsUri 'C.X448` - and negotiate the concrete version with `compatibleVersion` against the client e2e range, as `compatibleInvitationUri` does (Agent.hs:1362-1368). Create the receive queue Q_A subscribed (`newRcvQueue` with `subMode`), messaging mode so Bob can secure it. Choose the requester's KEM with `replyKEM_ v ownerKem_ pqSup` (Ratchet.hs:839): if the bundle advertises a KEM (owner `IKUsePQ`) the requester `AcceptKEM` - a **double KEM**: it both encapsulates to the address KEM (ciphertext) and includes its own new KEM public key (`generateSndE2EParams` → `sntrup761Enc` + a fresh keypair, Ratchet.hs:433-435), so PQ is bidirectional from message 1; if the bundle has no KEM and the requester wants PQ, it `ProposeKEM` (its own key only, PQ from message 2 if the owner supports it). Run `generateSndE2EParams g v (replyKEM_ …)`, `pqX3dhSnd` against the negotiated parameters, `initSndRatchet`, `createSndRatchet` - the body of `createRatchet_` (Agent.hs:1343-1350), with parameters from the passed bundle rather than a received invitation.
+- R3'. Build `AgentConfirmation {e2eEncryption_ = Just aliceSndParams, ratchetKeyId = Just ratchetKeyId, encConnInfo = ratchetEncrypt(AgentConnInfoReply (Q_A :| []) aliceProfile)}` - the `mkAgentConfirmation`/`mkConfirmation` bodies (Agent.hs:3780-3765) with the reply queue being Alice's own Q_A. Send it to the address queue unauthenticated with `agentCbEncryptOnce`, one-shot (as `sendInvitation` sends, Agent/Client.hs:1929-1934) - **synchronous**, with the same send-failure UX as today's classic contact join. Nothing is stored: a retry (chat re-invokes the join → `mkJoinInvitation` reuses Q_A + keys, 1418) re-builds the confirmation, advancing the send ratchet, and the owner absorbs the advance - a **failed send** is skipped when the owner establishes the ratchet (`maxSkip = 512`, Ratchet.hs:988), and a **lost reply** carries the current content and updates the owner's request by `XContactId` (ContactRequest.hs:99-101, 269); both testable. The requester does **not** SKEY the address (`QMContact`, not `senderCanSecure`); rotation is handled because the passed params are the current advertised keys. **Alice's profile is now inside `encConnInfo`, under the ratchet.** Alice's connection is `RcvConnection` (Q_A) with a send ratchet, until she receives Q_B. This "New `RcvConnection` + `ratchets` row" is a new state (today a New `RcvConnection` holds x3dh keys but no ratchet - the classic initiator builds the ratchet only at R5, `createRatchet` Agent.hs:3436), and it composes: connection type is derived from queue rows alone while the `ratchets` table is keyed independently by `conn_id`, so subscription (Agent.hs:1551), `connectionStats` (2658), and `allowConnectionAsync'` (888) never read the ratchet for a `RcvConnection`; the only handshake reader on it is `smpConfirmation` (R5').
+
+### Deferred (future work): async delivery + connect UX
+
+The synchronous send above fails in the user's face on a lost reply (the same wart as today's classic contact join), even though the request may have been delivered. Making it async is a separate, later change, not part of this DR work:
+
+- Delivery cannot use the message-delivery worker: a `SndQueue` is unique per `(host, port, snd_id)` and belongs to one connection (schema PK), while a contact address is one queue that many connections send to, so no per-connection SndQueue to it can exist. It would go through the **async command worker**, keyed by `(connId, server)` (`getAsyncCmdWorker`, Agent.hs:1856-1858), which already retries the `JOIN` command (`tryMoveableCommand` → `retrySndOp`, 2016-2024); each retry re-runs `joinConnSrv` (re-build + ratchet advance, which the owner absorbs - above), so nothing is stored. (`joinConnSrvAsync` for `CRContactUri` is `CMD PROHIBITED` today, Agent.hs:1452, and the `JOIN` handler falls back to sync `joinConnSrv`, 1899-1902; the `TBC` at Agent.hs:1897 is about async *receive*-queue creation - Q_A - and is orthogonal.)
+- The async join returns "connecting" early and completes via the events chat already handles (`joinContact` sets `ConnJoined`; the DR requester emits `CONF` in R5' and the chat allows it, exactly as the classic contact requester, driving msg 3 → `CON`; a permanent send failure still surfaces as `ERR → ConnFailed`).
+- This needs a chat change: the join API takes a `CreatedConnLink` (full + short link), not the bare `ConnectionRequestUri` it takes today, so the agent can LGET-gate on the owner's server (a real reachability check) and verify the fetched `linkConnReq` equals the passed full link before reporting success. Used only for DR addresses (link data advertises `ratchetKeys`); old / non-DR addresses stay on the current sync path.
+
+Owner side - a new dispatch branch and a new receive handler:
+
+- O1'. In `processClientMsg` (Agent.hs:3176-3187), add a branch in state `(Nothing, Just e2ePubKey)`: an `AgentConfirmation` with `ratchetKeyId = Just _` **and** `e2eEncryption_ = Just _` on a `ContactConnection` -> `smpAddressConfirmation` (new). A `ratchetKeyId` without `e2eEncryption_` is ignored (it does not match this branch and falls through as a non-DR confirmation). It must be placed **before** the existing `(PHEmpty, AgentConfirmation) | senderCanSecure queueMode` case (Agent.hs:3182-3184), because a contact-address queue is `QMContact` (not `senderCanSecure`) and would otherwise fall into `prohibited "handshake: missing sender key"` (Agent.hs:3184). The address queue's `e2eDhSecret` stays `Nothing` (it is never set for a contact address - `smpInvitation` does not set it, Agent.hs:3609-3622), so every request is decrypted with its own ephemeral key via this `(Nothing, Just e2ePubKey)` path.
+- O2'. `smpAddressConfirmation` (new, modeled on `smpConfirmation` initiating branch, Agent.hs:3405-3444): select the private triple `(pk1, pk2, pKem)` by `ratchetKeyId` from `address_ratchet_keys`; `pqX3dhRcv pk1 pk2 pKem aliceSndParams`; `initRcvRatchet` with the address connection's stored `PQSupport` (`connPQEncryption` of the address `InitialKeys` - `On` for `IKUsePQ` and `IKPQOn`, `Off` for `IKPQOff`; this is what lets `IKPQOn` accept the requester's proposed KEM), combined with version compatibility as `smpConfirmation` derives `pqSupport'` (Agent.hs:3410); `rcDecrypt` of `encConnInfo` performs the first ratchet step, giving the ratchet its send side too (as it does for the initiator today), so the owner can later reply. Parse `AgentConnInfoReply (Q_A :| []) aliceProfile`. Store the request with `createInvitation` on the address connection (`contact_conn_id`), exactly as a classic invitation - except the request value is the `CRConfirmation` variant (Part 3) carrying the post-decrypt ratchet state and Q_A, and `recipient_conn_info` is `aliceProfile` - so **no connection or `ratchets` row is created at receive**, as with a classic invitation. Emit `REQ` with the `invitation_id`. A resend is not deduplicated: like a resent classic invitation it produces another `REQ` (the connect-UX fix for that is separate chat work). An unknown or expired `ratchetKeyId`, or a decryption failure: discard and acknowledge, as an undecryptable message is dropped today. This establishes ratchet state on unauthenticated input before the user accepts - see "Receive-time establishment, state, and abuse".
+- O3'. `acceptContact'` for a DR request - a new branch that continues the ratchet instead of `joinConn`. `getInvitation` returns the request; its `CRConfirmation` variant gives the stored ratchet state and Q_A. Create the connection now (as `joinConn` does for a classic invitation) and `createRatchet` (AgentStore.hs:1419) from the stored ratchet state. Reuse `mkAgentConfirmation` (Agent.hs:3780-3785) to create Bob's receive queue Q_B and return `AgentConnInfoReply (Q_B :| []) bobInfo`; create Bob's send queue to Q_A (`newSndQueue`, generating Bob's own sender key) and secure Q_A with `SKEY` using that key (`agentSecureSndQueue`, valid because Q_A is messaging mode) - the securing key is Bob's own, not taken from Alice's message; send the response to Q_A as `AgentConfirmation {e2eEncryption_ = Nothing, ratchetKeyId = Nothing, encConnInfo = ratchetEncrypt(AgentConnInfoReply (Q_B :| []) bobInfo)}` via `sendConfirmation` (`agentCbEncrypt` over Bob's send queue to Q_A, `PHEmpty` because Q_A is `senderCanSecure`) - exactly the current contact msg 2 path (Client.hs:1916), not `agentCbEncryptOnce`. The reply content is `AgentConnInfoReply`, not `AgentConnInfo`: it takes the `mkAgentConfirmation` path with `e2eEncryption_ = Nothing`, not the `enqueueConfirmation` path (which produces `AgentConnInfo`, Agent.hs:3789). `rejectContact'` deletes the `conn_invitations` row (the current behaviour), discarding the inline ratchet; no connection was created, so there is nothing else to clean up.
+
+Requester side, receiving the response on Q_A:
+
+- R5'. `smpConfirmation` needs a new branch `RcvConnection … Nothing` (today only `RcvConnection … Just` and `DuplexConnection … Nothing` exist, Agent.hs:3403-3447). It looks up the ratchet first (`getRatchet`) and, if there is none, falls through to `prohibited "conf: incorrect state"` - so a classic initiator (a New `RcvConnection` with x3dh keys but no ratchet) that receives a stray `Nothing`-confirmation keeps today's exact outcome; only a DR requester, which holds a send ratchet, takes the new path. Alice already holds the send ratchet, so `rcDecrypt` advances it and creates the receive side; parse `AgentConnInfoReply (Q_B :| []) bobInfo`. **This mirrors the classic contact requester exactly**: `setRcvQueueConfirmedE2E` on Q_A, `createRatchet` the advanced ratchet, store the reply as a `NewConfirmation`, and emit **`CONF`** - the app then calls `allowConnection'` (supplying `ownConnInfo` for msg 3), which drives `connectReplyQueues` (create Alice's send queue to Q_B, `SKEY`, upgrade to `DuplexConnection`, `enqueueConfirmation` the `AgentConnInfo` msg 3). Because Q_B is sender-securable, sending `AgentConnInfo` completes Alice with `CON` (Agent.hs:2252) - no `HELLO`. The only difference from the classic requester is that the ratchet is pre-built (from R2') rather than built from Bob's Snd params here, so there is no `CONF`-less auto-completion and no separate storage of Alice's own info.
+- R6'/completion. Unchanged from the current contact handshake, and modern (no `HELLO`). The exchange is three agent↔agent wire messages - Alice → address queue (msg 1), Bob → Q_A (msg 2, an `AgentConfirmation` carrying `AgentConnInfoReply` with Q_B), Alice → Q_B (msg 3, an `AgentConfirmation` carrying `AgentConnInfo`) - the same shape as the current contact flow, where msg 1 was `AgentInvitation`; here it is the ratchet-establishing `AgentConfirmation`. (`CON` is not a wire message - it is the agent→app event; `HELLO` and `AgentConnInfo` are the wire messages.) `HELLO` belongs to the older non-`senderCanSecure` path (duplexHandshake v2, before SKEY): there the confirmation secures the queue in-band (`PHConfirmation` carries the sender key, Client.hs:1918) and the receiver replies with `HELLO` (`ICDuplexSecure` → `enqueueDuplexHello`, Agent.hs:3457-3458). Both Q_A and Q_B here are messaging-mode - Q_A by R2', Q_B via `createReplyQueue` → `SCMInvitation` → `QMMessaging` (Agent.hs:1233,1458,3783) - so the sender secures with SKEY and sends `PHEmpty` (Client.hs:1918), the dispatch takes the `senderCanSecure` branch (Agent.hs:3182-3184), and each agent raises the `CON` app event locally off msg 3 - Bob on receiving it (`senderKey = Nothing`, Agent.hs:3459-3461), Alice on sending it (Agent.hs:2252) - with no separate `HELLO` wire message. (msg 2's `AgentConnInfoReply` only sets Q_A `Confirmed`, Agent.hs:2254.) Invitations are two messages because the initiator's queue is already in the link; a contact address needs three because Bob's receive queue Q_B is only delivered in msg 2. The third message no longer has a ratchet role: Bob's X3DH params are pre-published, so the agreement is complete once Bob receives msg 1 (in the current flow Bob's Snd params instead arrive in msg 2). msg 2 and msg 3 are queue setup - msg 2 delivers Q_B, msg 3 secures Q_B so Alice can send to Bob and signals Bob's `CON`; neither negotiates the ratchet. A one-directional exchange (the RPC) needs no Q_B and is two messages.
+
+Net code touch points: `joinConnSrv` (new requester branch), `processClientMsg` (new owner dispatch), `smpConfirmation` (new `RcvConnection … Nothing` branch and `AgentConnInfoReply` acceptance), `acceptContact'` (new continue-ratchet branch), a new `smpAddressConfirmation` reusing `createInvitation`/`getInvitation` with the sum request value, and the link data and storage of Part 3-4. `rejectContact'` is unchanged (it deletes the `conn_invitations` row either way).
+
+### Receive-time establishment, state, and abuse
+
+This is the substantive departure from the current flow. Today `smpInvitation` creates only a lightweight `NewInvitation` and emits `REQ` (Agent.hs:3618-3621); no connection or ratchet exists until the user accepts. For DR the request is under the ratchet, so to show the requester's profile in `REQ` the owner must decrypt it, which means establishing the ratchet at **receive**, before accept.
+
+Design decision (Q1): decrypt at receive. Both use cases need the request content at `REQ` - a person decides to accept from the profile, and a service bot needs the request payload to act. Deferring decryption to accept would make `REQ` contentless and does not fit the service case, so it is not done.
+
+Consequences:
+
+- No connection is created at receive, exactly as for a classic invitation. O2' stores the request with `createInvitation` on the address connection; the post-decrypt ratchet state and Q_A live inline in the `CRConfirmation` request value (`cr_invitation`). O3' (accept) creates the connection, `createRatchet` from the stored state, and adds Bob's queues, becoming a `DuplexConnection`; `rejectContact'` deletes the `conn_invitations` row.
+- Per incoming `AgentConfirmation` the owner does one `pqX3dhRcv` (three DH plus, with PQ, one `sntrup761` decapsulation) and one `rcDecrypt`, on unauthenticated input, and writes one `conn_invitations` row - more CPU than the current `NewInvitation`, the same order of state (no connection, no `ratchets` row until accept).
+
+Abuse (Q2): a contact address already accepts and processes unauthenticated invitations today, so this is a degree-worse version of an existing surface, not a new class. It is bounded by the address queue quota (an attacker fills it, the owner drains and acknowledges) and, optionally, by basic auth on the address (already supported for contact addresses, `optBasicAuth`). The per-request state is a single `conn_invitations` row - the same class as a classic contact request - so it is subject to the same limits and lifecycle, with no DR-specific dedup or TTL. Proof-of-work or a stricter gate can be added later; it is out of scope here and noted as a follow-up.
+
+`acceptContact'`/`rejectContact'` keep taking the `invitation_id` from `REQ` unchanged; the only difference is that `getInvitation` returns a request that is either a `CRInvitation` URI (current `joinConn` path, O3-O6) or a `CRConfirmation` (continue-ratchet path, O3'). Nothing in the `REQ`/accept/reject flow or the chat client changes - the change is contained in the agent.
+
+### The four communication layers, per message (verified against code)
+
+Layers, outermost (server-visible) first:
+
+- **L1 `ClientMsgEnvelope`** (Protocol.hs:1089), `PubHeader {phVersion, phE2ePubDhKey :: Maybe PublicKeyX25519}` (1096) - **this is where per-queue encryption is agreed** (not L2). `phE2ePubDhKey` is the sender's e2e DH public key; the recipient combines it with the queue's e2e private key: `(e2eDhSecret, e2ePubKey_) -> (Nothing, Just e2ePubKey) -> e2eDh = dh' e2ePubKey e2ePrivKey` (Agent.hs:3172-3178). `agentCbEncryptOnce` (Client.hs:2214) puts a **fresh ephemeral** pubkey (generated 2217, set 2223) - used when the sender has no send queue (the address queue), whose `e2eDhSecret` stays `Nothing`, so it decrypts every message with the per-message ephemeral. `agentCbEncrypt` (Client.hs:2203) puts the **send queue's persistent** e2e pubkey (`Just` on a confirmation, 2210); the recipient stores the secret via `setRcvQueueConfirmedE2E`, and *later* messages send `phE2ePubDhKey = Nothing` (`sendAgentMessage`, 2080).
+- **L2 `ClientMessage PrivHeader`** (Protocol.hs:1113), `PrivHeader = PHConfirmation APublicAuthKey | PHEmpty` (1115) - **queue securing / authorization, not encryption**. `PHConfirmation` carries the sender's AUTH key for in-band securing (v2, non-`senderCanSecure`); `PHEmpty` when the sender secured the queue with SKEY out-of-band. `PHEmpty` on every message here is about securing, and says nothing about encryption (that is L1). Set in `sendConfirmation` (Client.hs:1918), `sendInvitation` (1934), `sendAgentMessage` (2079).
+- **L3 `AgentMsgEnvelope`** (Agent/Protocol.hs:829, encoding 851) - outside the ratchet. `AgentConfirmation` ('C') carries `e2eEncryption_` (Snd X3DH params, agrees DR) + `encConnInfo`; `AgentInvitation` ('I') carries `connReq` (Rcv X3DH params) + plaintext `connInfo` (no DR); `AgentMsgEnvelope` ('M') carries `encAgentMessage`.
+- **L4 `AgentMessage`** (Agent/Protocol.hs:883, encoding 893) - inside the ratchet. `AgentConnInfo` ('I'), `AgentConnInfoReply` ('D', reply queues + info), `AgentMessage APrivHeader AMessage` ('M'; `AMessage` includes `HELLO`, Agent/Protocol.hs:1018-1020). **Absent when L3 is `AgentInvitation`** (that profile is per-queue-only - the gap this plan closes).
+
+Send routing: msg 1 (to address) → `sendInvitation` today / a new `agentCbEncryptOnce` confirmation send for DR; msg 2 → `secureConfirmQueue` → `sendConfirmation` (Agent.hs:3747); msg 3 → `connectReplyQueues` → `enqueueConfirmation` → delivery worker `AM_CONN_INFO` → `sendConfirmation` (Agent.hs:3733,3789,2183). `AM_CONN_INFO`/`AM_CONN_INFO_REPLY` both go through `sendConfirmation` (2183-2184); other `AMessage`s go through `sendAgentMessage` wrapping `AgentMsgEnvelope` 'M' (2192-2193).
+
+Current contact handshake (address does **not** advertise DR):
+
+| msg | L1 `PubHeader.phE2ePubDhKey` (per-queue enc) | L2 `PrivHeader` (securing) | L3 `AgentMsgEnvelope` | L4 `AgentMessage` |
+|---|---|---|---|---|
+| 1 Alice→addr | `Just` fresh ephemeral, `agentCbEncryptOnce` (Client.hs:1933,2223) | `PHEmpty` (1934) | `AgentInvitation` {connReq = Alice Rcv params, connInfo = profile} (Client.hs:1932) | — none (profile per-queue only) |
+| 2 Bob→Q_A | `Just` Bob's send-queue e2e pubkey, `agentCbEncrypt` (1920,2210) | `PHEmpty` [`senderCanSecure`] (1918) | `AgentConfirmation` {e2eEncryption_ = **Just Bob Snd params**, encConnInfo} (Agent.hs:3765) | `AgentConnInfoReply` (Q_B) bobInfo, DR-enc (Agent.hs:3785) |
+| 3 Alice→Q_B | `Just` Alice's send-queue e2e pubkey, `agentCbEncrypt` (1920,2210) | `PHEmpty` [`senderCanSecure`] (1918) | `AgentConfirmation` {e2eEncryption_ = **Nothing**, encConnInfo} (Agent.hs:3802) | `AgentConnInfo` aliceInfo, DR-enc (Agent.hs:3789) |
+
+New DR handshake (address advertises DR):
+
+| msg | L1 `PubHeader.phE2ePubDhKey` (per-queue enc) | L2 `PrivHeader` (securing) | L3 `AgentMsgEnvelope` | L4 `AgentMessage` |
+|---|---|---|---|---|
+| 1 Alice→addr | `Just` fresh ephemeral, `agentCbEncryptOnce` [same] | `PHEmpty` [same] | **`AgentConfirmation`** {e2eEncryption_ = **Just Alice Snd params**, **ratchetKeyId = Just**, encConnInfo} [was `AgentInvitation`] | **`AgentConnInfoReply`** (Q_A) aliceProfile, **DR-enc** [was plaintext connInfo] |
+| 2 Bob→Q_A | `Just` Bob's send-queue e2e pubkey, `agentCbEncrypt` [same] | `PHEmpty` [same] | `AgentConfirmation` {e2eEncryption_ = **Nothing**, ratchetKeyId = Nothing, encConnInfo} [was Just Bob Snd params] | `AgentConnInfoReply` (Q_B) bobInfo, DR-enc [same] |
+| 3 Alice→Q_B | `Just` Alice's send-queue e2e pubkey, `agentCbEncrypt` [same] | `PHEmpty` [same] | `AgentConfirmation` {e2eEncryption_ = Nothing, encConnInfo} [same] | `AgentConnInfo` aliceInfo, DR-enc [same] |
+
+Net difference: **only msg 1 and msg 2's L3/L4 change.** msg 1's L3 becomes `AgentConfirmation` (was `AgentInvitation`) carrying Alice's Snd params + `ratchetKeyId`, and the profile moves from plaintext L3 to DR-encrypted L4 (`AgentConnInfoReply`) - the whole point of the change. msg 2 drops `e2eEncryption_` (Bob no longer sends Snd params - the ratchet is agreed from msg 1). msg 3 is unchanged. L1 (per-queue encryption - each queue agrees its own secret via the sender's e2e pubkey in the `PubHeader` on the first message to it) and L2 (securing, `PHEmpty` because SKEY is used) are unchanged throughout; the DR change is entirely at L3/L4. The only new send code is msg 1 (an `AgentConfirmation` fired to the address with `agentCbEncryptOnce`, like `sendInvitation` but with a confirmation envelope).
+
+## Part 3 - types and link data
+
+### Fixed data - unchanged
+
+`FixedLinkData` (Protocol.hs:1824) is not touched. The double-ratchet keys go entirely in mutable data, so an existing address advertises them without a new link (the fixed data is hash-committed and cannot change). Fixed data keeps only `agentVRange`, `rootKey`, `linkConnReq`, `linkEntityId`.
+
+### Mutable data - ratchet keys bundle
+
+Appended to `UserContactData` (Protocol.hs:1840); the encoding stops at a trailing tail (Protocol.hs:1981), so earlier versions ignore it:
+
+```haskell
+newtype RatchetKeyId = RatchetKeyId ByteString -- opaque short id; one Encoding instance, shared below
+
+data AddressRatchetKeys = AddressRatchetKeys
+  { ratchetKeyId :: RatchetKeyId, -- identifies this bundle; changes on rotation, echoed in the request
+    e2eParams :: CR.RcvE2ERatchetParamsUri 'C.X448 -- version range + both X3DH keys + optional KEM
+  }
+instance Encoding AddressRatchetKeys where ... -- the key-bundle instance; both fields required
+
+data UserContactData = UserContactData
+  { direct :: Bool, owners :: [OwnerAuth], relays :: [ConnShortLink 'CMContact],
+    userData :: UserLinkData,
+    ratchetKeys :: Maybe AddressRatchetKeys -- whole bundle optional, one Encoding instance
+  }
+```
+
+`e2eParams` is the existing `RcvE2ERatchetParamsUri 'C.X448` (`E2ERatchetParamsUri VersionRangeE2E k1 k2 (Maybe (RKEMParams s))`, Ratchet.hs:282-286) - the same type a `CRInvitationUri` advertises - with `StrEncoding`/`Encoding` already defined (Ratchet.hs:302-374). There is no bespoke key type and no reconstruction: the requester negotiates the concrete version with `compatibleVersion` against its own e2e range, exactly as `compatibleInvitationUri` does for an invitation (Agent.hs:1362-1368), giving `RcvE2ERatchetParams` for `pqX3dhSnd`. The KEM is optional: `Nothing` gives an X448-only ratchet (as when `PQSupport` is off), `Just` a hybrid one, matching `generateRcvE2EParams`'s `PQSupport` gate (Ratchet.hs:439-445).
+
+The address-creation parameter is `InitialKeys` (Ratchet.hs:864) - the same 3-way choice as invitations, not a bare `PQSupport`. Currently `IKUsePQ` is prohibited for `SCMContact` (Agent.hs:990,1198) because a contact address carries no owner keys; this change lifts that prohibition. The bundle plays the published-contact-request role, so its KEM follows `initialPQEncryption False pqInitKeys` (Ratchet.hs:882) - exactly as the requester's contact request does today (Agent.hs:1422):
+
+- `IKUsePQ` - the bundle advertises the KEM; the requester encapsulates to it, so PQ from message 1.
+- `IKPQOn` (`IKLinkPQ PQSupportOn`) - the bundle is X448-only (no KEM advertised), but the owner's ratchet supports PQ (`connPQEncryption` = On, Ratchet.hs:888); the requester proposes its own KEM (R2'), so PQ from message 2.
+- `IKPQOff` (`IKLinkPQ PQSupportOff`) - X448-only, and the owner's ratchet does not support PQ even if the requester proposes it.
+
+Advertising the KEM adds ~1158 B to the rotated, widely-fetched link data, which is why `IKPQOn` exists (PQ one round later, without the size cost). The owner generates the bundle with `generateRcvE2EParams g v (initialPQEncryption False pqInitKeys)` (Ratchet.hs:439), stores the private triple `(pk1, pk2, pKem)` (Part 4), and advertises `e2eParams` by wrapping the public `E2ERatchetParams` in the address's e2e version range (`toVersionRangeT`; or `mkRcvE2ERatchetParams` from the stored privates, Ratchet.hs:412) - the same private-key shape `createRatchetX3dhKeys`/`getRatchetX3dhKeys` already store (AgentStore.hs:1362-1367). `ratchetKeys` is set by the agent when it signs mutable link data (`Crypto.ShortLink.encodeSignUserData`), not by the application.
+
+### Authentication of the advertised keys
+
+No signature is added on the keys: the mutable link data already signs them. `decryptLinkData` (Crypto/ShortLink.hs:106-114) verifies `sig2` over the mutable `UserContactData` by `rootKey`, so `ratchetKeys` is root-signed. This is the X3DH anti-substitution property: an SMP server cannot substitute the keys without forging the root signature. The signer is the root Ed25519 key (the address's signing identity); the X3DH keys are separate DH keys (X448, which cannot sign). A single owner signs address data ("we don't use multiple owners"), so the root signature alone is sufficient - no per-key signature. A malicious server can still serve an older but validly-signed `UserContactData` (rollback to a retired bundle); this is bounded by the retention window and by the ratchet advancing after the first message, and a signature does not prevent it. Inline ratchet params in a `CRInvitationUri` contact request are not in signed link data and remain unsigned - a separate change, out of scope here.
+
+### Request envelope
+
+`AgentConfirmation` (Protocol.hs:830-834) gains an optional `ratchetKeyId` - the `ratchetKeyId` of the `AddressRatchetKeys` bundle the requester used, so the owner selects the matching private keys:
+
+```haskell
+AgentConfirmation
+  { agentVersion :: VersionSMPA,
+    e2eEncryption_ :: Maybe (SndE2ERatchetParams 'C.X448), -- reused: Alice's Snd params in DR msg 1
+    ratchetKeyId :: Maybe RatchetKeyId,                    -- selects the owner's key generation
+    encConnInfo :: ByteString
+  }
+```
+
+`ratchetKeyId` is a separate optional selector (the shared `RatchetKeyId` newtype), not the bundle - the owner already holds the published public bundle and looks up its private keys by this id. It reuses the existing `e2eEncryption_` for Alice's Snd params rather than a new combined bundle; the minor cost is two correlated `Maybe`s (`ratchetKeyId = Just` is only meaningful with `e2eEncryption_ = Just`). **A `ratchetKeyId` with `e2eEncryption_ = Nothing` is ignored** - O2' requires both (there are no Snd params to run `pqX3dhRcv`), so such a message falls through to the current dispatch as if it had no `ratchetKeyId`.
+
+Encoding (extends Protocol.hs:853-866): from `addressDRVersion`, `smpEncode (agentVersion, 'C', e2eEncryption_, ratchetKeyId, Tail encConnInfo)`; `ratchetKeyId` is `Just` for an address-DR confirmation and `Nothing` for the current joiner-to-initiator and initiator-to-joiner confirmations; earlier versions omit the field entirely and use `smpEncode (agentVersion, 'C', e2eEncryption_, Tail encConnInfo)`. Parsing gates the field on `agentVersion`. `CRInvitationUri` is unchanged - a connection request URI holds Rcv parameters and must not hold Snd parameters.
+
+### Stored request - the invitation record
+
+The `conn_invitations` record stays; only the type of the stored request widens. From chat's point of view a DR request is still an invitation - it "contains a confirmation" instead of an invitation URI - so `REQ`, `acceptContact'`/`rejectContact'`, and the chat side are unchanged; the change is contained in the agent. The `NewInvitation`/`Invitation` request field (`cr_invitation`, stays `NOT NULL`) becomes a sum:
+
+```haskell
+data ContactRequest
+  = CRInvitation (ConnectionRequestUri 'CMInvitation) -- classic: joinConn on accept (O3-O6)
+  | CRConfirmation DRRequest                          -- DR: continue the ratchet on accept (O3')
+
+data DRRequest = DRRequest
+  { drRatchet :: RatchetX448,        -- post-decrypt receiving ratchet (with send side), stored inline
+    drReplyQueue :: SMPQueueInfo,    -- Q_A, where the owner replies
+    drAgentVersion :: VersionSMPA,   -- negotiated at receive; needed to build the connection shell at accept
+    drPQSupport :: PQSupport         -- the address's PQ setting for this connection
+  }
+```
+
+`recipient_conn_info` holds the profile in both cases. `getInvitation`/`createInvitation` carry `ContactRequest`; `acceptContact'` branches on the constructor. There is no dedup column: a resent request produces another `REQ`, exactly as a resent classic invitation does.
+
+`drAgentVersion`/`drPQSupport` are stored because the accept flow creates the connection **shell** through `newConnToAccept` → `newConnToJoin` (via `prepareConnectionToAccept`, called by chat's sync accept before `acceptContact'`, Internal.hs:914,925) and `newConnToJoin` today derives `connAgentVersion`/`pqSupport` from the `ConnectionRequestUri` (Agent.hs:1277-1293); a `CRConfirmation` has no URI, so the values negotiated at receive (O2') are stored and used to build the shell.
+
+Three readers of the widened `connReq` field (all via `getInvitation`) branch on the constructor:
+- `acceptContact'` (Agent.hs:1479, sync): `CRInvitation cr` → `joinConn … cr` (classic, unchanged); `CRConfirmation dr` → the O3' continue-ratchet path.
+- `newConnToAccept` (Agent.hs:1296, via `prepareConnectionToAccept`): `CRInvitation cr` → `newConnToJoin … cr` (unchanged); `CRConfirmation dr` → create the `NewConnection` shell from `drAgentVersion`/`drPQSupport` (`createNewConn`, generating the connId).
+- `acceptContactAsync'` (Agent.hs:900): `CRInvitation cr` → `joinConnAsync … cr` (unchanged); `CRConfirmation _` → `throwE $ CMD PROHIBITED` (async DR accept is deferred; DR requests accept synchronously). Chat's REQ/accept is unaffected either way - it only ever passes `invId`, never the `ContactRequest`, which stays internal to the agent.
+
+Storage: `cr_invitation`'s `ToField`/`FromField` encode `CRInvitation` as the legacy `strEncode` URI (unchanged from before, so the format is downgrade-safe) and `CRConfirmation` as JSON (`J.encode` of `DRRequest`). `FromField` peeks the first byte: `{` → JSON `CRConfirmation`, else `strDecode` → `CRInvitation` (a URI never starts with `{`). `DRRequest` uses manual `ToJSON`/`FromJSON` (extensible), and `SMPQueueInfo` gets a base64 `StrEncoding` + JSON to sit inside it. `smpInvitation` (Agent.hs:3618) wraps its `connReq` in `CRInvitation`; `smpAddressConfirmation` (O2') writes `CRConfirmation`.
+
+## Part 4 - key rotation (client-driven)
+
+Rotation is independent of the handshake above and is driven by the client app, not the agent. The agent never rotates on its own - it lacks the app's intent and the mutable link data (profile/badge and other short-link data). The app rotates by calling `setConnShortLink` with the rotate flag; the whole ratchet-keys bundle - both X448 keys and the KEM - is generated fresh each time.
+
+### Schema
+
+```sql
+-- one row per ratchet-keys generation for an address; the current generation plus the most recent retained ones.
+-- private side of the advertised RcvE2ERatchetParamsUri - same shape as the ratchets x3dh
+-- columns and createRatchetX3dhKeys (AgentStore.hs).
+CREATE TABLE address_ratchet_keys(
+  address_ratchet_key_id INTEGER PRIMARY KEY AUTOINCREMENT,
+  conn_id BLOB NOT NULL REFERENCES connections ON DELETE CASCADE,
+  ratchet_key_id BLOB NOT NULL,     -- the published id echoed by requests
+  x3dh_priv_key_1 BLOB NOT NULL,    -- X448
+  x3dh_priv_key_2 BLOB NOT NULL,    -- X448
+  pq_priv_kem BLOB,                 -- RcvPrivRKEMParams (sntrup761 keypair); NULL when PQ is off for this address
+  created_at TEXT NOT NULL DEFAULT(datetime('now'))
+);
+CREATE UNIQUE INDEX idx_address_ratchet_keys ON address_ratchet_keys(conn_id, ratchet_key_id);
+
+-- a DR request stays in conn_invitations with NO schema change: cr_invitation now holds a ContactRequest
+-- sum (an invitation URI or a confirmation carrying the post-decrypt ratchet + reply queue), so it stays
+-- NOT NULL - no nullable change, no new column on conn_invitations, no new table for the request.
+```
+
+`cr_invitation` stays `NOT NULL` - only its decoded value gains a variant (Part 3), so the invitations flow, `REQ`, and chat are unchanged; the only new storage is the `address_ratchet_keys` table. The link signing key is already on the address queue (`rcv_queues.link_priv_sig_key`, M20250322), so nothing is added there - rotation and retrofit re-sign mutable data with it. PostgreSQL mirrors this. Migration `M20260712_address_dr`.
+
+### Rotation logic
+
+The app rotates by calling `setConnShortLink` with the rotate flag; there is no automatic, agent-driven rotation. On rotation:
+
+1. `generateRcvE2EParams` for a fresh generation - two X448 keys, and an sntrup761 keypair only if PQ is on for this address - with a fresh `ratchetKeyId`.
+2. Recompute mutable link data with the new `AddressRatchetKeys` (the public `e2eParams`), re-sign with the root key (`encodeSignUserData`, key from `rcv_queues.link_priv_sig_key`), and `LSET` it to the address queue (`setConnShortLink` path).
+3. Insert the new `address_ratchet_keys` row (`x3dh_priv_key_1`, `x3dh_priv_key_2`, `pq_priv_kem`).
+
+### Retention
+
+Retention is count-based, not time-based: on each rotation `deleteOldAddressRatchetKeys` keeps the newest `keepAddressKeys` generations per address (default 3, ordered by `address_ratchet_key_id`) and deletes older ones. There is no `retired_at` column, no time window, and no `cleanupManager` step. A request that used a recently-retired bundle still decrypts while that generation is retained; how long a recorded first message stays decryptable after a compromise of the current private keys is therefore bounded by the retained-generation count and the app's rotation cadence (both app-controlled). Unaccepted DR request rows in `conn_invitations` are handled exactly like unaccepted classic invitation requests - no DR-specific cleanup (a DR request is one `conn_invitations` row, the same class of state as a classic contact request).
+
+## Part 5 - backward compatibility
+
+- A requester older than `addressDRVersion`, or an address without `ratchetKeys`, uses R2/R3 (`AgentInvitation`); the owner uses O1-O8. Unchanged.
+- The owner dispatches on the envelope: `AgentInvitation` -> `smpInvitation` (current); `AgentConfirmation` with `ratchetKeyId` on a `ContactConnection` -> `smpAddressConfirmation` (new). Both coexist.
+- `AgentConfirmation` without `ratchetKeyId` remains the current confirmation on established connections.
+- An existing address gains `ratchetKeys` via a new agent API (e.g. `updateContactAddressLink`) that the app calls with the mutable link data (profile/badge and any other short-link data): the agent generates the DR bundle if absent (the first `address_ratchet_keys` row and its stored private keys), adds `ratchetKeys` to `UserContactData`, re-signs with `rcv_queues.link_priv_sig_key`, and `LSET`s it. **Only mutable data changes - the address (link) is unchanged**, because the keys are in mutable, not fixed, data. Requesters that fetch the updated data use DR; older ones still use `AgentInvitation`. The agent does not do this on its own (it lacks the profile and the user's intent); the app drives it, combined with the full→short address migration.
+
+## Part 6 - tests
+
+- Encoding roundtrips: `UserContactData` with and without `ratchetKeys`, and with the KEM present and absent; `AgentConfirmation` with and without `ratchetKeyId`, across versions.
+- Address creation advertises `ratchetKeys` (the `RcvE2ERatchetParamsUri`); `decryptLinkData` (Crypto/ShortLink.hs:100) verifies signatures and the requester negotiates the advertised params to a concrete version, with and without the KEM.
+- Both PQ modes: an address whose bundle carries a KEM gives a hybrid ratchet (`pqEncryption` on); one without gives an X448-only ratchet.
+- End to end: a DR-advertising address; a new requester establishes the ratchet, sends its profile under it, owner emits `REQ`, accepts, both reach `CON`; assert the profile never travels under per-queue-only encryption; assert `pqEncryption` on.
+- Rotation and retrofit: request against the current bundle; against a just-retired bundle within the window still decrypts; against a bundle past the window is discarded and the requester times out; an address that adds `ratchetKeys` via `LSET` is then reached by DR while an old requester still uses `AgentInvitation`.
+- Backward compatibility: old requester against a DR address connects via `AgentInvitation`; new requester against a non-DR address falls back to `AgentInvitation`.
+
+## Part 7 - phases
+
+1. Link data: `AddressRatchetKeys` in `UserContactData` (reusing `RcvE2ERatchetParamsUri`), encoding, `encodeSignUserData`; `AgentConfirmation.ratchetKeyId`; address creation taking `InitialKeys` (lifting the `IKUsePQ`-for-`SCMContact` prohibition), generating (`generateRcvE2EParams`, KEM per `initialPQEncryption False`) and storing the first `address_ratchet_keys` row.
+2. Handshake: thread the optional `Maybe AddressRatchetKeys` through `joinConnection`/`joinConn`/`joinConnSrv` (present → DR branch, absent → classic); requester R2'/R3' (synchronous one-shot send); owner O1'/O2'/O3' storing the DR request as a `conn_invitations` row whose request value is the `CRConfirmation` variant; `smpConfirmation` `RcvConnection … Nothing` branch and `AgentConnInfoReply` acceptance; end-to-end connection with the profile under the ratchet. Tests pass `AddressRatchetKeys` directly (chat wiring is later work).
+3. Rotation and retrofit: schema migration, `rotateRatchetKeys`, retention window, cleanup step, app-driven `LSET` retrofit (with the full→short address migration), rotation/retrofit tests.

plans/2026-07-24-signed-service-requests.md

@@ -0,0 +1,59 @@
+# Signed service requests
+
+Optional Ed25519 signature on service RPC requests, constructed and verified in the agent (not the bot), bound to the request's double ratchet. Requests only — responses stay authenticated by the address/ratchet. Signing is optional; a bot decides whether to require it. The agent is stateless: the meaning of a signer key (identity, resource) is the bot's concern.
+
+## Wire — `Simplex.Messaging.Agent.Protocol`
+
+Extend the existing `'A'` inner message; `Maybe` absent = unsigned, so the unsigned path is unchanged:
+
+```haskell
+AgentServiceRequest (NonEmpty SMPQueueInfo) (Maybe RequestSignature) MsgBody
+
+data RequestSignature = RequestSignature C.PublicKeyEd25519 (C.Signature 'C.Ed25519)
+```
+
+## Binding
+
+```
+binding = sha3-256("SimpleXService" <> rcAD)
+sig     = Ed25519.sign(sk, binding <> payload)
+```
+The service recomputes `binding` from its own `rcAD` and verifies.
+
+- `rcAD` = the ratchet associated data (`Ratchet.rcAD`) — the shared connection security code: identical on both ratchets by construction (`pubKey(requester ephemeral) <> pubKey(service key)`), stable, and unique per request (fresh requester ephemeral). Already on the ratchet; nothing derived or stored.
+- sha3-256 here is not for uniformity or secrecy (both moot: the value is signed, not keyed, and only a ratchet holder can craft a valid request). It gives a canonical fixed-length, domain-tagged binding; the 32-byte fixed prefix also makes `binding <> payload` unambiguous.
+- Domain string `"SimpleXService"`: separates this signature from other uses of the signing key.
+- Not covered: reply queues (the AEAD protects them in transit; addresses may use redundant queues).
+- Anti-relay: a signature bound to one session's rcAD does not verify under another's (both parties' keys differ). Replay of the encrypted blob is handled separately by transport dedup.
+
+## Sign (requester) — `Simplex.Messaging.Agent`
+
+- `sendServiceRequest` / `sendServiceRequestAsync` gain a `Maybe` Ed25519 signing key.
+- `joinConnSrv'` DR path takes the ratchet straight from the `createRatchet_`/`getSndRatchet` line (both now yield `(RatchetX448, params)`) and computes `serviceReqBinding` from its `rcAD`; the `mkInner :: SMPQueueInfo -> ByteString -> AgentMessage` closure calls `signServiceReq signKey_ binding payload` — `RequestSignature pub (sign' pk (binding <> payload))` when a key is given, `Nothing` otherwise.
+- Async carries the key in `JRServiceReq {requestKey :: Maybe C.PrivateKeyEd25519}` (enabled `StrEncoding (PrivateKey Ed25519)`); the JOIN worker deserializes it and signs after building the ratchet.
+
+**Status:** implemented and tested in simplexmq-3 (sync + async); invalid signature → `A_SERVICE ASEBadSignature` (logs + `ERR` event), no invitation.
+
+## Verify (service) — `smpContactRequest`
+
+After `initRcvRatchet_` + decrypt, on `AgentServiceRequest (replyQueue :| _) sig_ payload`, one helper does the check:
+
+`verifyServiceReq rc payload sig_ :: Either String (Maybe C.PublicKeyEd25519)`
+- `Nothing` → `Right Nothing` (unsigned).
+- `Just (RequestSignature key sig)` → recompute `serviceReqBinding rc` and `C.verify' key sig (binding <> payload)`; `Right (Just key)` if valid, else `Left err`.
+
+Then:
+- `Right key_` → `storeInvitation … True` + `notify $ SREQ invId key_ payload`.
+- `Left err` → `logError` + `notify (ERR (AGENT (A_SERVICE ASEBadSignature)))`, no invitation.
+
+Dedup unchanged.
+
+## Event / API
+
+- `SREQ :: InvitationId -> Maybe C.PublicKeyEd25519 -> MsgBody -> AEvent AEConn`.
+- `StrEncoding (PrivateKey Ed25519)` enabled so a caller (e.g. via `JRServiceReq`) can carry the signing key.
+
+## Tests
+
+- `testSignedServiceRequest` (sync) + `testSignedServiceRequestAsync` — signed round-trip delivers the exact signer key on `SREQ` (`sigKey_ == Just signPub`).
+- Unsigned path unchanged (existing service tests carry `Nothing` for the new field).

plans/2026-08-05-proxy-relay-error-attribution.md

@@ -0,0 +1,81 @@
+## Root cause: PRXY errors are attributed to the forwarding server instead of the destination relay
+
+When private routing is enabled and the destination relay is unreachable, the client reports
+**"Error connecting to forwarding server smp5.simplex.im"** — naming a preset server that the client
+connected to successfully. Retrying rotates to the next proxy (`getNextServer`, `Agent/Client.hs:689`)
+and produces the same message with a different preset server, so the destination server is never named
+and the failure looks like an outage of our own infrastructure.
+
+### Reproduction
+
+Connecting to a contact address on an unresolvable host (`simplex.server.home`, no DNS record):
+
+```
+-- private routing off (correct)
+BROKER {brokerAddress = "smp://VvXX…@simplex.server.home:5223",
+        brokerErr = NETWORK {networkError = NEConnectError {connectError = "…does not exist (Name or service not known)"}}}
+
+-- private routing on (misattributed)
+SMP {serverAddress = "smp://…@smp5.simplex.im,…onion",
+     smpErr = PROXY {proxyErr = BROKER {brokerErr = NETWORK {networkError = NEFailedError}}}}
+```
+
+### The asymmetry between the two proxied paths
+
+A server returns `PROXY (BROKER …)` only from `smpProxyError` (`Client.hs:804-815`), which is called
+exclusively where the proxy failed to reach the relay — `PRXY` (`Server.hs:1444`) and `PFWD`
+(`Server.hs:1466`). The error therefore *always* describes the proxy→relay hop. The two paths then
+diverge in how the agent wraps it:
+
+**PFWD — keeps both addresses** (`Agent/Client.hs:1183-1189`): the proxy's error arrives as
+`Left ProxyClientError` and is thrown as `PROXY {proxyServer, relayServer, proxyErr}`.
+
+**PRXY — drops the relay** (`Agent/Client.hs:713`): `connectSMPProxiedRelay` has no `Either` layer, so
+the error arrives as `PCEProtocolError` and `liftClient SMP` maps it to `SMP <proxyAddr> (PROXY …)`
+(`Agent/Client.hs:1244`). The destination address is discarded.
+
+Both clients read the second shape as a client→proxy failure and word it accordingly
+(`SimpleXAPI.kt:2692`, `ErrorAlert.swift:117`), which is never what it means.
+
+### Fix
+
+In `newProxiedRelay`, map proxy-reported `PROXY (BROKER …)` errors to the same shape `PFWD` already
+produces:
+
+```haskell
+proxyRelayError :: HostName -> ErrorType -> AgentErrorType
+proxyRelayError proxyHost = \case
+  e@(SMP.PROXY (SMP.BROKER _)) -> PROXY {proxyServer = protocolClientServer smp, relayServer = …destSrv, proxyErr = ProxyProtocolError e}
+  e -> SMP proxyHost e
+```
+
+`liftClient` applies this only to `PCEProtocolError`, so genuine client↔proxy failures (response
+timeout, network error, proxy transport version) still map to `BROKER <proxy> …` and remain attributed
+to the proxy. Both apps already render the resulting shape correctly, with no client change:
+*"Forwarding server smp5.simplex.im failed to connect to destination server simplex.server.home."*
+
+The guard is `BROKER` rather than every `ProxyError`, so the remap covers exactly the misattributed
+class and nothing else. `BASIC_AUTH` is deliberately excluded — the proxy returns it when proxying is
+disabled or the basic auth does not match (`Server.hs:1416-1420`), which is a client↔proxy fact and is
+correctly attributed today. `NO_SESSION` is returned only for `PFWD`. `PROTOCOL` describes the relay
+but is not rendered as a proxy-connection error by either client, so leaving it unchanged keeps the
+diff to the errors that actually produce a wrong message.
+
+### Blast radius
+
+- `temporaryAgentError` (`Agent/Client.hs:1572-1580`) and `serverHostError` (`:1594-1596`) already match
+  both shapes with the same helpers — retry and proxy-fallback behaviour is unchanged.
+- `clientServiceError` (`:1268-1273`) has no `PROXY`-shape twin for `BROKER NO_SERVICE`, but both ends
+  document that case as unreachable (`Client.hs:812`); left as is.
+- simplex-chat `Subscriber.hs:1819-1820` handles both shapes; send failures move from `SndErrProxy` to
+  `SndErrProxyRelay`, i.e. "Destination server error" rather than "Error" — also more accurate.
+- `SMP _ (PROXY _)` becomes unreachable, making `smpProxyErrorAlert` in both clients dead code. Removing
+  it is a follow-up in simplex-chat, not required by this change.
+
+### Verification
+
+- Reproduced before/after with a CLI built against this branch: the error now carries
+  `relayServer = "smp://VvXX…@simplex.server.home:5223"`, and the direct (non-proxied) path is
+  byte-identical to before.
+- `SMPProxyTests`: 45 examples, 0 failures — including `fails when fallback is prohibited` and both
+  retry tests, which exercise `newProxiedRelay` and the error classification.

plans/2026-08-09-fast-queue-rotation-plan.md

@@ -0,0 +1,187 @@
+# Fast queue rotation — implementation plan
+
+Branch: ep/drop-agent-versions. RFC: ../rfcs/2026-08-09-fast-queue-rotation.md.
+
+Model: redundant delivery, no flip. `QADD` adds the new receive queue R'. From `QADD` until R' is
+secured the sender writes every message to both old and R' (double delivery, not a move); once R' is
+secured the sender writes new messages to R' only, while old delivers its already-scheduled tail and
+the `QEND` appended to it. `QEND` removes a named queue. The recipient drops duplicates (double
+ratchet), so the order and which queue delivers do not matter, as long as every message arrives on at
+least one queue. Rotation away from a dead server works because every message up to securing is
+scheduled on R' too.
+
+Roles: A initiates (its receive queue rotates; A receives on R'). B sends to A and secures R'.
+
+## Why redundant delivery removes the hard parts
+
+- No boundary, no drain, no last-message id. A never decides how much of old to read.
+- A dead old server loses nothing B still holds: every undelivered message is scheduled on R' as well.
+- A dead new server does not suspend delivery: old keeps delivering until R' is secured.
+- The double ratchet already drops duplicates (`AGENT A_DUPLICATE`) and tolerates bounded reordering,
+  and the delivery schema already writes one message to several send queues (`enqueueMessageB` +
+  `enqueueSavedMessageB`).
+
+## The one ordering constraint
+
+A must hold R''s secret before it reads any R' data message. A data message reaching R' before the
+confirmation is dropped as "no keys" (`processClientMsg`, `(Nothing, Nothing)` arm, line 3611), which
+loses it when old is dead. So the confirmation is the first message B sends on R'. R''s delivery
+worker does not start while R' is securing, so its accumulated rows cannot outrun the confirmation.
+`ICQSndSecure` sends the confirmation and only then starts the worker. This holds on restart too (see
+Worker gate).
+
+## New definitions
+
+Agent/Protocol.hs
+- Condition fast rotation on the existing `rpcAddressSMPAgentVersion` (v8, `Protocol.hs:322`).
+- New `AMessage` constructor `QEND SndQAddr` (tag `QE`), the address of the queue to remove. v8-only,
+  and only sent during fast rotation, so peers below v8 never parse it.
+- `SndSwitchStatus` constructors `SSSecuringQueue` (old, while R' secures) and `SSSendingQEND` (old,
+  after R' is secured — it drains its tail and `QEND` but takes no new messages).
+- `InternalCommand` constructor `ICQSndSecure SMP.SenderId`.
+
+No receive-side switch status, no boundary, no drain state.
+
+## Schema
+
+None. `SSSecuringQueue` uses `snd_queues.switch_status`; R' is secured into `rcv_queues.e2e_dh_secret`.
+No new columns, no migration.
+
+## Sender B
+
+### Dual scheduling from QADD
+
+`enqueueMessageB` writes a delivery row for the head send queue and for each `filter isActiveSndQ`
+tail queue (`Agent.hs:2345`). Adjust the selection two ways: additionally include a securing
+replacement queue on a v8 connection (`connAgentVersion cData >= rpcAddressSMPAgentVersion && status == New && isJust dbReplaceQueueId`),
+and exclude a terminating queue (`sndSwchStatus == Just SSSendingQEND`). The version guard keeps the
+slow path unchanged — there R' is also `New` with a replace reference during `QKEY`/`QUSE`, but it must
+not be dual-scheduled. `SSSendingQEND` is a fast-path-only status, so the exclusion never affects the
+slow path. The gate below is inert for the slow path anyway, since it never starts R''s worker while
+`New`.
+
+- `QADD` until R' secured: old is the head (active) and R' is the securing replacement, so every `SEND`
+  writes both rows. old delivers at once; R''s rows accumulate behind its gate.
+- R' secured: R' is the head (primary) and old is `SSSendingQEND` (excluded), so a `SEND` writes R'
+  only. old keeps its worker and delivers whatever was already scheduled on it, plus `QEND`.
+
+### Worker gate
+
+`submitPendingMsg` (`Agent.hs:2437`) and `resumeMsgDelivery` (`2421`) — the two `getDeliveryWorker`
+callers that start delivery — skip a queue with `status == New && isJust dbReplaceQueueId`, so neither
+a `SEND` nor startup starts R''s worker while it secures. Startup resumes delivery through
+`resumeMsgDelivery` (`resumeDelivery` line 1848, and `getAllSndQueuesForDelivery` line 1943), so R' is
+skipped there; `resumeAllCommands` (1883) resumes R''s `ICQSndSecure`, which secures R' and only then
+starts its worker.
+
+### Steps
+
+`qAddMsg` (fast branch, under the connection lock, `Agent.hs:3855`):
+- Add R' as the slow path does (line 3870): `addConnSndQueue (sq_) {primary = True, dbReplaceQueueId = Just old}`, `New`.
+- Duplicate **every** undelivered message on old to R': for each pending row on old
+  (`SELECT internal_id FROM snd_message_deliveries WHERE conn_id = ? AND snd_queue_id = old AND failed = 0`),
+  `createSndMsgDelivery db R' internalId`. This is the loss-prevention step: old's not-yet-sent
+  messages are duplicated onto R', so if old later fails they are already on R'. If old is already
+  down, nothing was sent and the whole backlog is duplicated.
+- `enqueueCommand (Just newSrv) (ICQSndSecure sndId)`; `setSndSwitchStatus SSSecuringQueue` on old
+  (where the slow path sets `SSSendingQKEY`, line 3874); notify `SWITCH QDSnd SPStarted`. old keeps
+  delivering; R''s worker is gated.
+
+`ICQSndSecure sId` (retryable, under `tryWithLock`):
+1. If old is already gone, a prior attempt finished; return. Otherwise find R' by `sId`.
+2. `secureSndQueue` (SKEY) R' — idempotent, since `sndPrivateKey` was persisted by `qAddMsg`
+   (`QueueStore/STM.hs:213`: same key → `Right ()`, different key → `AUTH`).
+3. Send the confirmation on R' (`sendConfirmation`; empty body, both peers already know each other;
+   `e2eEncryption_ = Nothing`, no ratchet step). It is the first message on R'.
+4. On success, in one transaction: `setSndQueueStatus R' Active` (the gate lifts), `setSndQueuePrimary R'`
+   (R' becomes the head; its replace reference is cleared), and `setSndSwitchStatus old (Just SSSendingQEND)`
+   (old takes no new messages but keeps its worker). Then `submitPendingMsg c R'` (the worker starts and
+   flushes the accumulated rows after the confirmation), `enqueueMessages [old, R'] (QEND oldAddr)`
+   (appended after old's tail, delivered on both), and notify `SWITCH QDSnd SPSecured`. From here a
+   `SEND` goes to R' only; old delivers its tail then `QEND` and is removed when `QEND` is sent.
+
+A temporary error retries from step 1; nothing is torn down. A permanent `AUTH` (should not occur, R'
+was secured with B's own key) leaves both queues and surfaces `A_QUEUE`.
+
+`QEND` sent — new `AM_QEND_` arm in `runSmpQueueMsgDelivery`, modelled on `AM_QTEST_` (`Agent.hs:2567`):
+on a successful send of `QEND addr`, remove the named send queue (`TM.delete` its worker,
+`deleteConnSndQueue addr`), make the remaining queue the sole primary (`setSndQueuePrimary`, which
+clears its `replace_snd_queue_id`), and notify `SWITCH QDSnd SPCompleted` (as `AM_QTEST_` does, line
+2591). This re-primary is a no-op on the send side — step 4 already made R' primary before `QEND` was
+enqueued. The handler is idempotent — a second `QEND` send finds the named queue already gone and does
+nothing. `QEND` is sent on both queues; removing old's send queue also drops any `QEND` still pending
+on old. The R' copy reliably removes old
+and reaches A even when old is dead; the old copy is best effort. Once old's send queue is gone, `SEND`
+schedules to R' only.
+
+## Recipient A
+
+A is subscribed to old (primary, `RSSendingQADD`) and R' (created at rotation start,
+`dbReplaceQueueId = old`).
+
+- **Confirmation on R'.** In `processClientMsg`, `(Nothing, Just e2ePubKey)` case, add an arm before the
+  `senderCanSecure` arm (`Agent.hs:3476`), guarded by `isJust (dbReplaceQueueId rq)`. In one
+  transaction: `setRcvQueueConfirmedE2E rq (C.dh' e2ePubKey e2ePrivKey) (min v phVer)` (secures R') and
+  `setRcvQueuePrimary R'` (clears R''s replace reference). Then `ack`, and notify `SWITCH QDRcv SPConfirmed`.
+  No conn-info processing, no ratchet step, no deferral. Redelivery is idempotent: R' now has `e2e_dh_secret`, so a re-sent
+  confirmation reaches the `(Just e2eDh, Just _)` arm (line 3608) and is acked — correct here, since
+  there is no backlog to hold.
+- **Data on R'.** With R''s replace reference cleared, a data message on R' takes the ordinary path
+  (`(_, dbReplaceQueueId=Nothing)`, line 3503) — no old-deletion, no `RSSendingQUSE` check. A copy
+  already read on old is dropped as `A_DUPLICATE`; a copy read first on R' advances the ratchet and
+  old's copy is then the duplicate.
+- **`QEND oldAddr` on either queue.** New `AMessage` handler (`qEndMsg`, a `qDuplex` handler like
+  `qAddMsg`): `findRQ oldAddr` the receive queue to remove. Mark it deleted (`setRcvQueueDeleted`, so
+  `getRcvQueuesByConnId_`'s `deleted = 0` filter excludes it at once and a restart does not resurrect
+  it) and `enqueueCommand (Just oldServer) (ICDeleteRcvQueue oldRcvId)` for the server `DEL` and record
+  removal — the async, crash-safe path `abortConnectionSwitch` uses, which resumes on restart and does
+  not block `QEND`, **not** the synchronous `deleteQueue` of `finalizeSwitch`, which would stall if old
+  is unreachable. `ICDeleteRcvQueue` (`Agent.hs:2224`) currently retries a temporary error forever;
+  bound it with the same persisted `rcv_queues.delete_errors`/`deleteErrorCount` mechanism `deleteQueueRec`
+  uses (2884): on a temporary error `incRcvDeleteErrors`, and at the limit `deleteConnRcvQueue` and
+  stop. The count is in the database, so the bound survives restarts, and its only other caller
+  (`abortConnectionSwitch'`, 2739) deletes an alive queue that succeeds well before the limit. `qEndMsg`
+  does **not** re-primary R' — the confirmation arm (above) owns R''s primary flag and replace
+  reference. `QEND` on old and the confirmation on R' travel on different queues with no order between
+  them, so `QEND` on old can be processed first (it sits only behind old's tail); re-primarying then
+  would clear R''s `dbReplaceQueueId` and the later confirmation would miss the rotation arm and never
+  secure R'. So `qEndMsg` only removes the named queue. Re-create the notification subscription
+  (`when enableNtfs $ sendNtfSubCommand ns (NSCCreate, [connId])`); notify
+  `SWITCH QDRcv SPCompleted`; `ackDel` the `QEND`. Received on both queues, the second finds it already
+  marked deleted and is a no-op.
+
+No drain, no boundary, no finalize command. Old is removed when `QEND` arrives, not by counting.
+
+## Abort / version
+
+- Fast rotation runs only when `connAgentVersion >= v8`; otherwise the `QKEY`/`QUSE` slow path runs
+  unchanged.
+- `canAbortRcvSwitch` (`Agent/Store.hs:210`) returns false for `RSSendingQADD` when `connAgentVersion >= v8`
+  (at v8 B always chooses fast, so A treats a sent `QADD` as committed). Its signature gains
+  `connAgentVersion`; both callers pass it from `cData` — `abortConnectionSwitch'` (2730) and
+  `rcvQueueInfo` in `connectionStats` (2976).
+
+## Losses and duplication
+
+- No boundary loss: the `QADD` step **duplicates** old's entire undelivered backlog onto R', and every
+  later message up to securing is scheduled on both queues, so if old fails it loses nothing B still
+  holds. The only messages old can strand are those its server already accepted but had not handed to
+  A — the ordinary store-and-forward risk, present whenever a server fails with unread messages, and
+  empty if old was already down (a down server accepted nothing).
+- Duplicates: the double ratchet drops them (`A_DUPLICATE`); `checkMsgIntegrity`'s `MsgDuplicate` is
+  only a flag, not the mechanism.
+- The 512 skip bound (`Crypto/Ratchet.hs:953`) does not bite on the rotation: each queue delivers in
+  order and every message B still holds is on R', so A reads a contiguous stream with only small
+  cross-queue reordering. A store-and-forward residual (above) is an ordinary loss, not introduced here.
+
+## Tests
+
+- new/new, old stopped right after `QADD`: rotation completes; all messages delivered on R'; old
+  removed by `QEND` on R'.
+- new/new, both alive: messages delivered on both, deduped; old removed by `QEND`.
+- new/old and old/new: fall back to the `QKEY`/`QUSE` path.
+- crash during securing: restart does not start R''s worker; `ICQSndSecure` resumes, secures R',
+  starts the worker, sends `QEND`.
+- `QEND` received on both queues: old removed once, the second receipt is a no-op.
+- `QEND` on old processed before the confirmation on R': R' still secures, because `qEndMsg` does not
+  clear R''s replace reference; rotation completes.

plans/20260522_01_smp_public_namespaces.md

@@ -0,0 +1,455 @@
+# Server: SMP support for public namespaces
+
+> **⚠ Implementation diverged from this plan.** Six audit rounds reshaped the
+> original design. **The shipped code differs in several load-bearing ways:**
+>
+> - **Wire format**: `NameRecord` is now JSON (aeson), not the custom binary
+>   ABNF this plan documents. See `protocol/simplex-messaging.md` §Resolver
+>   commands and `src/Simplex/Messaging/Protocol.hs` ToJSON/FromJSON instances.
+> - **No cache**: the TTL + FIFO + byte-cap cache, in-flight coalescing,
+>   `psqueues` dep, and `cache_*` INI keys are all gone. Every RSLV becomes
+>   one `eth_call` bounded by `rpcMaxConcurrency` + `rpcTimeoutMs`. See
+>   `src/Simplex/Messaging/Server/Names.hs`.
+> - **No `allow_dangerous_colocation` flag**: the proxy co-location guard
+>   was demoted to a startup `logWarn` (the flag was always-on because
+>   `[PROXY]` has no enable toggle).
+> - **Module shape**: `Names/Resolver.hs` was merged into `Names.hs`; only
+>   `Names/Eth/RPC.hs` and `Names/Eth/SNRC.hs` remain as separate modules.
+> - **Test list**: of the 15 specs listed below, ~7 shipped; the rest were
+>   either superseded by the cache removal (CacheSpec) or deferred
+>   (ForwardedRslvSpec, MockRpcSpec, StartupGuardSpec, UrlValidationSpec,
+>   EipChecksumSpec).
+>
+> Sources of truth: `CHANGELOG.md` (release notes),
+> `protocol/simplex-messaging.md` §Resolver commands (wire format),
+> `src/Simplex/Messaging/Server/Names*.hs` (implementation). This file is
+> retained as historical context; do not treat it as a specification.
+
+Implementation plan for Part 2 of [RFC 2026-05-21-public-namespaces](https://github.com/simplex-chat/simplex-chat/blob/ep/namespace/docs/rfcs/2026-05-21-public-namespaces.md). Adds a forwarded-only `RSLV <lookup_key>` SMP command that returns `NAME <NameRecord>` read from the SNRC contract via a Reth+Nimbus JSON-RPC endpoint. Smp-server becomes name-capable by `[NAMES] enable: on`.
+
+Out of scope: `Simplex.Messaging.Client` API, agent-side resolution flow, `ServerRoles.names` in the agent, default-router list, reverse resolution, multicoin/text records, state proofs.
+
+## Architecture
+
+```mermaid
+sequenceDiagram
+  participant C as Client
+  participant P as Proxy (storage role)
+  participant N as Name server (names role)
+  participant E as Ethereum endpoint<br/>(Reth+Nimbus)
+
+  C ->> P: PFWD(enc(RSLV key))
+  P ->> N: RFWD(enc(RSLV key))
+  note over N: verifyTransmission True →<br/>vc SResolver (RSLV _) → VRVerified
+  N ->> N: cache lookup
+  alt cache miss
+    N ->> E: eth_call(SNRC, namehash(key))
+    E -->> N: ABI bytes
+    note over N: ABI decode + zero-owner check + cache insert
+  end
+  N -->> P: RFWD(enc(NAME rec | ERR AUTH))
+  P -->> C: PRES(enc(NAME rec | ERR AUTH))
+```
+
+RSLV is **forwarded-only** — direct RSLV is rejected `CMD PROHIBITED`. This preserves the RFC's two-server resolution: the name server sees the lookup key but never the client's IP, session, or identity.
+
+## Protocol
+
+Shared library: `src/Simplex/Messaging/Protocol.hs` and `src/Simplex/Messaging/Transport.hs`.
+
+**Version.** `Transport.hs:226`: `namesSMPVersion = VersionSMP 20`. Bump `currentClientSMPRelayVersion`, `currentServerSMPRelayVersion`, `proxiedSMPRelayVersion` to 20. Pre-v20 binaries lack the `RSLV_` tag; v20 binaries with sessions negotiated at v < 20 reject `RSLV_` at the parameter parser. The proxied-version bump 18 → 20 is safe (v19's `RecipientService`/`NotifierService` aren't in the forwarded whitelist; v18's `BLOCKED info` is already version-branched at `Protocol.hs:1943`).
+
+**Party kind.** Append `Resolver` to `Party` (line 335); add `SResolver` (line 349), `TestEquality` clause (line 361), `PartyI Resolver` (line 394). `queueParty SResolver = Nothing` (falls through line 412). `partyClientRole SResolver = Nothing`.
+
+**`RSLV` command.**
+
+```haskell
+RSLV :: LookupKey -> Command Resolver
+newtype LookupKey = LookupKey ByteString
+
+instance Encoding LookupKey where
+  smpEncode (LookupKey s) = smpEncode s
+  smpP = do
+    n <- lenP
+    when (n > 64) $ fail "LookupKey too large"
+    LookupKey <$> A.take n
+```
+
+Name-syntax validation is client-side per RFC; the server treats the key as opaque bytes. Tag `"RSLV"`, version guard inside `protocolP v (CT SResolver RSLV_)`: `| v >= namesSMPVersion -> Cmd SResolver . RSLV <$> _smpP`.
+
+**Testnet/mainnet selector**: how the `#testnet:name` namespace appears in `LookupKey` bytes is determined by the SNRC contract (Part 1) — confirm with Part 1 before merging.
+
+**`NAME` response.**
+
+```haskell
+NAME :: NameRecord -> BrokerMsg
+```
+
+Tag `"NAME"`. Symmetric version guards on encode (in `encodeProtocol v`) and decode (in `protocolP v NAME_`): `| v >= namesSMPVersion -> ...`. `NameRecord` has **no `Encoding` typeclass instance** — the typeclass cannot version-branch. Use top-level helpers `nameRecBytes :: VersionSMP -> NameRecord -> ByteString` and `parseNameRec :: VersionSMP -> Parser NameRecord`, mirroring the `IDS QIK` precedent at `Protocol.hs:1912–1979`.
+
+**`NameRecord` schema and wire layout.**
+
+```haskell
+data NameRecord = NameRecord
+  { nrDisplayName  :: Text                    -- ≤255 bytes UTF-8
+  , nrOwner        :: NameOwner               -- 20 raw bytes
+  , nrChannelLinks :: [NameLink]
+  , nrContactLinks :: [NameLink]
+  , nrAdminAddress :: Maybe Text
+  , nrAdminEmail   :: Maybe Text
+  , nrExpiry       :: Int64                   -- Unix seconds, ≥ 0
+  , nrIsTest       :: Bool
+  }
+
+newtype NameOwner = NameOwner ByteString   -- bare ctor NOT exported; smart ctor enforces length 20
+newtype NameLink  = NameLink  Text         -- bare ctor NOT exported; smart ctor enforces ≤1024 bytes
+
+unNameOwner :: NameOwner -> ByteString
+unNameOwner (NameOwner bs) = bs
+
+unNameLink :: NameLink -> Text
+unNameLink (NameLink t) = t
+```
+
+Field additions are gated by future SMP version bumps (matching the `IDS QIK` precedent at `Protocol.hs:1912–1979`) — no separate record-version field.
+
+| Field | Encoding | Max bytes |
+|---|---|---|
+| `nrDisplayName` | 1-byte length prefix + UTF-8 | 1 + 255 |
+| `nrOwner` | 20 raw bytes, no prefix | 20 |
+| `nrChannelLinks`, `nrContactLinks` | 1-byte count + per-element (Word16 BE len + UTF-8); combined cap **8 entries** across both lists | 1 + Σ(2 + ≤1024) |
+| `nrAdminAddress`, `nrAdminEmail` | `'0'` or `'1'` + (1-byte length + UTF-8 if `'1'`) | 1 + 1 + 255 |
+| `nrExpiry` | two big-endian `Word32` | 8 |
+| `nrIsTest` | `'T'` or `'F'` | 1 |
+
+`Encoding NameLink` reads the Word16 length **before** `A.take` allocates — going through the existing `Large` wrapper allows up to 65 535 bytes per element. There is no `Encoding [a]` instance — use `smpEncodeList` / `smpListP` / a bounded variant:
+
+```haskell
+smpListPUpTo :: Encoding a => Int -> Parser [a]
+smpListPUpTo cap = do
+  n <- lenP
+  when (n > cap) $ fail "list too long"
+  A.count n smpP
+
+parseNameRec _v = do
+  nrDisplayName  <- smpP
+  nrOwner        <- smpP
+  nrChannelLinks <- smpListPUpTo 8
+  nrContactLinks <- smpListPUpTo (8 - length nrChannelLinks)
+  nrAdminAddress <- smpP
+  nrAdminEmail   <- smpP
+  nrExpiry       <- smpP
+  when (nrExpiry < 0) $ fail "expiry must be non-negative"
+  nrIsTest       <- smpP
+  pure NameRecord{..}
+```
+
+Both list parsers fail at the count step before allocating; the second inherits the residual budget. Canonical encoding by construction: every primitive has exactly one valid byte form — two name servers reading the same SNRC state produce byte-identical responses.
+
+**Wire-size budget.** `paddedProxiedTLength = 16226` is the plaintext input to `cbEncrypt` (`Server.hs:2117`); `pad` reserves 2 bytes → framed transmission ≤ 16 224 bytes. Combined-link cap 8 yields max payload ≈ 9 050 bytes — generous margin.
+
+**Error semantics.** A single wire code: `ERR AUTH`. Per RFC, this collapses every failure (name not found, malformed key, names disabled, RPC unreachable, decode error, timeout). Resolver internally distinguishes the cause for stats only.
+
+**Forwarded-only access.** Direct RSLV is rejected with `CMD PROHIBITED`. The shape of `THAuthServer` alone cannot discriminate direct from forwarded (`Transport.hs:852` sets `sessSecret' = Just _` for every v6+ direct client too). An explicit `forwarded :: Bool` flag is threaded through `verifyTransmission` (see below).
+
+## Server changes
+
+All edits in `src/Simplex/Messaging/Server.hs`.
+
+**`forwarded :: Bool` plumbing.** Three signatures change:
+
+- `verifyTransmission :: Bool -> ...` (line 1233) — direct path passes `False` (lines 1152–1153), forwarded path passes `True` (line 2129).
+- `verifyLoadedQueue :: Bool -> ...` (line 1238) — receives the flag from `verifyTransmission` (lines 1235, 1240).
+- `verifyQueueTransmission :: Bool -> ...` (line 1244) — receives and uses the flag.
+
+New `vc` clauses inside `verifyQueueTransmission`:
+
+```haskell
+vc SResolver (RSLV _) | forwarded = VRVerified Nothing
+                      | otherwise = VRFailed (CMD PROHIBITED)
+vc SResolver _ = VRFailed (CMD PROHIBITED)   -- defensive catch-all
+```
+
+**Forwarded whitelist** (`Server.hs:2132`):
+
+```haskell
+Cmd SResolver (RSLV _) -> True
+```
+
+**`processCommand` branch** (alongside line 1481):
+
+```haskell
+Cmd SResolver (RSLV (LookupKey key)) -> do
+  st <- asks (rslvStats . serverStats)
+  incStat (rslvReqs st)
+  asks namesEnv >>= \case
+    Nothing -> incStat (rslvDisabled st)  $> response (corrId, NoEntity, ERR AUTH)
+    Just nenv -> liftIO (resolveName nenv key) >>= \case
+      Right rec     -> incStat (rslvSucc st)     $> response (corrId, NoEntity, NAME rec)
+      Left NotFound -> incStat (rslvNotFound st) $> response (corrId, NoEntity, ERR AUTH)
+      Left _        -> incStat (rslvEthErrs st)  $> response (corrId, NoEntity, ERR AUTH)
+```
+
+**Shutdown.** Add `closeNamesEnv :: NamesEnv -> IO ()` calling `closeManager`. Wire into `closeServer` (`Server.hs:247`):
+
+```haskell
+closeServer = do
+  asks (smpAgent . proxyAgent) >>= liftIO . closeSMPClientAgent
+  asks namesEnv >>= liftIO . mapM_ closeNamesEnv
+```
+
+In-flight `resolveName` calls during shutdown receive `ConnectionClosed` → `EthHttpErr` → masked-leader cleanup runs → waiters unblock with `ERR AUTH`.
+
+**`incStat` relocation.** Defined at `Server.hs:2220`, currently unexported. Move to `Server/Stats.hs` (one-line transplant + export) so `Resolver.hs` can use it.
+
+**Co-located proxy warning.** `newEnv` logs a startup warning whenever `allowSMPProxy = True` and `namesConfig = Just _`. RSLV is the first slow forwarded command; on a proxy host it can serialise other forwarded commands on the same proxy-relay session up to `rpcTimeoutMs` per cache miss. The warning is not a hard refusal because `[PROXY]` has no `enable: on/off` toggle — proxy is always on for every smp-server. `forkForwardedCmd` async dispatch is the longer-term fix, tracked as a follow-up; once the proxy role is gateable per-server, the warning can be tightened back to a refusal.
+
+## Resolver subtree
+
+New module tree at `src/Simplex/Messaging/Server/Names/`:
+
+| Module | Contents |
+|---|---|
+| `Names.hs` | Façade — re-exports `NamesConfig`, `NamesEnv`, `ResolveError`, `resolveName`, `newNamesEnv`, `closeNamesEnv`. |
+| `Names/Resolver.hs` | All types + cache + in-flight + `resolveName`. Helpers exported directly (no `.Internal` per codebase convention). **Test seam**: `NamesEnv` holds `ethCall` as a function value, so tests construct stubs via `newNamesEnvWith`. |
+| `Names/Eth/RPC.hs` | `EthRpcEnv`; `ethCallReal` via `http-client` + `withResponse` + `brReadSome rpcMaxResponseBytes`. JSON-RPC error / HTTP error split. `rpcMaxConcurrency` semaphore. `Authorization` header from `rpcAuth`. |
+| `Names/Eth/SNRC.hs` | `EthAddress`, Keccak-256 namehash via `crypton`'s `Crypto.Hash.Algorithms.Keccak_256` (mirroring `Crypto.hs:1023–1025` for SHA3), hand-rolled bounded Solidity ABI codec, `getRecord` with zero-owner detection. **Ethereum's Keccak ≠ NIST SHA3-256.** |
+
+**ABI codec invariants**, enforced before any allocation: `offset + 32 ≤ buf.length`; `offset + 32 + length ≤ buf.length`; `offset ≥ headEnd` (no backward jumps); every length ≤ per-field cap; `string[]` outer length × 32 ≤ buf.length; recursion depth ≤ 2; `uint256 → Int64` rejects if any high 24 bytes non-zero; UTF-8 via `decodeUtf8'` returns `EthDecodeErr`.
+
+**Zero-owner → `NotFound`**: ENS-style resolvers return zeroed records for non-existent names. After ABI decode, if `nrOwner == NameOwner (B.replicate 20 0)` return `Left NotFound`.
+
+**Errors.**
+
+```haskell
+data ResolveError = NotFound | EthHttpErr | EthRpcErr { rpcCode :: Int, rpcMessage :: Text }
+                  | EthDecodeErr | TimedOut
+```
+
+All collapse to `ERR AUTH`. `EthRpcErr` carries JSON-RPC `error` object — method-not-found (SNRC not deployed at `snrc_address`) is logged immediately on the first error after a recent success: `logError "NAMES: JSON-RPC error from endpoint — check snrc_address: <code> <message>"`. No automatic retry.
+
+**Cache.** TTL + FIFO eviction. `TVar (OrdPSQ LookupKey Word64 NameRecord, Int)` — priority = monotonic-ns at insert; the `Int` is running byte count. `cacheLookup` is one STM transaction (read, expiry-check, expired-delete-with-byte-decrement). `cacheInsert` is one STM transaction: while `size > cacheMaxEntries` OR `bytes + sizeOf(rec) > cacheMaxBytes`, `minView` to drop oldest, then `insert`. Byte counter prevents `100 000 × 9 KB ≈ 900 MB` worst-case blow-up.
+
+**Request coalescing** (async-exception safe via `E.mask`):
+
+```haskell
+resolveName env bs = do
+  let k = LookupKey bs
+  now <- getMonotonicTimeNSec
+  atomically (cacheLookup env k now) >>= \case
+    Just rec -> incStat (rslvCacheHits ...) $> Right rec
+    Nothing  -> do
+      incStat (rslvCacheMiss ...)
+      ticket <- atomically $ TM.lookup k (inflight env) >>= \case
+        Just mv -> pure (Waiter mv)
+        Nothing -> newEmptyTMVar >>= \mv -> TM.insert k mv (inflight env) $> Leader mv
+      case ticket of
+        Waiter mv -> atomically (readTMVar mv)
+        Leader mv -> E.mask $ \restore -> do
+          r <- restore (fetchOnceTimed env bs)
+                 `E.catch` \(e :: E.SomeException) -> pure (Left (mapEthErr e))
+          atomically $ putTMVar mv r >> TM.delete k (inflight env)
+          case r of Right rec -> atomically (cacheInsert env k now rec); Left _ -> pure ()
+          pure r
+
+fetchOnceTimed env bs =
+  System.Timeout.timeout (rpcTimeoutMs (config env) * 1000) (fetchOnce env bs) >>= \case
+    Just r  -> pure r
+    Nothing -> pure (Left TimedOut)
+```
+
+`E.mask` ensures `putTMVar + TM.delete` runs even on async exception; `fetchOnceTimed` runs under `restore` so it remains interruptible. Waiters always see a value; the in-flight TMap entry is always removed.
+
+`fetchOnce`, `mapEthErr`, `scrubUrl`, `cacheLookup`, `cacheInsert` are internal to `Resolver.hs`. `getMonotonicTimeNSec` from `GHC.Clock` — first monotonic-clock use in the codebase; clock-jump safe.
+
+**STM contention.** Cache hits are read-only `readTVar` — STM scales. Cache writes under sustained miss traffic can retry; `CacheSpec` asserts < 5% retry at 4 readers + 1 writer @ 1k RPS. If observed higher, swap `TVar` for `IORef` + `atomicModifyIORef'`.
+
+**Multicoin and text records** are not in `NameRecord`. If Part 1 contract returns them from `getRecord`, extend `NameRecord` and the wire-size budget. **Confirm with Part 1 author before implementing `Eth/SNRC.hs`.**
+
+## Configuration
+
+`ServerConfig` (`Env/STM.hs:142`) gains one field `namesConfig :: Maybe NamesConfig`. `Env` (`Env/STM.hs:261`) gains `namesEnv :: Maybe NamesEnv`. `newEnv` constructs it after `proxyAgent` (line 605) with the co-location guard.
+
+```haskell
+data NamesConfig = NamesConfig
+  { ethereumEndpoint     :: Text          -- http(s), no userinfo, explicit port required
+  , snrcAddress          :: NameOwner     -- 20 bytes
+  , rpcAuth              :: Maybe RpcAuth -- required when https & non-loopback host
+  , cacheSeconds         :: Int           -- 300
+  , cacheMaxEntries      :: Int           -- 100000
+  , cacheMaxBytes        :: Int           -- 67108864 (64 MB)
+  , rpcTimeoutMs         :: Int           -- 3000
+  , rpcMaxResponseBytes  :: Int           -- 262144 (256 KB)
+  , rpcMaxConcurrency    :: Int           -- 8
+  }
+
+data RpcAuth = AuthBearer Text | AuthBasic Text Text
+```
+
+INI parsing in `Server/Main.hs`:
+
+- `validateUrl` (using new `network-uri` dep): accepts only http(s), non-empty host, **explicit port** (rejects `http://localhost` defaulting to 80 while Reth is on 8545), no userinfo, no query/fragment. Rejects `https://...` without `rpc_auth` when host is non-loopback. On rejection: `logError` + `exitFailure`.
+- `parseEthAddr`: accepts `0x[0-9a-fA-F]{40}` and the same without `0x`. Mixed-case → verify EIP-55 checksum and reject mismatch (catches typos).
+- `parseRpcAuth`: reads optional `rpc_auth` key; format `bearer <token>` or `basic <user>:<pass>`.
+- `scrubUrl`: strips userinfo from all log lines mentioning the endpoint, including inside `mapEthErr`.
+- Transition-aware error logging: log immediately on first error after a recent success, then at most hourly while persisting + summary at every stats reset.
+
+Default INI template (`Server/Main/Init.hs`, after `[PROXY]`):
+
+```
+[NAMES]
+# Public-namespace resolution (SNRC on Ethereum).
+# Requires an Ethereum JSON-RPC endpoint (Reth+Nimbus). See deployment guide.
+# Cannot be combined with [PROXY] enable: on by default — see allow_dangerous_colocation.
+# Restart required to change settings.
+enable: off
+# Same-host:
+# ethereum_endpoint: http://127.0.0.1:8545
+# Central Reth via Caddy:
+# ethereum_endpoint: https://eth.simplex.chat:443
+# rpc_auth: basic <username>:<password>
+# snrc_address: 0x0000000000000000000000000000000000000000
+# cache_seconds: 300
+# cache_max_entries: 100000
+# cache_max_bytes: 67108864
+# rpc_timeout_ms: 3000
+# rpc_max_response_bytes: 262144
+# rpc_max_concurrency: 8
+# allow_dangerous_colocation: off
+```
+
+Upgrade from a pre-v6.6 INI: missing `[NAMES]` section → disabled. No operator action required.
+
+## Operator deployment
+
+Two supported topologies. smp-server is agnostic — only `ethereum_endpoint` changes.
+
+**Topology A (same-host)**: smp-server, Caddy (optional), Reth, Nimbus all on one box. `ethereum_endpoint: http://127.0.0.1:8545`.
+
+**Topology B (central Reth, N smp-server hosts — recommended for fleets)**: one operator runs one eth host with Reth+Nimbus behind Caddy on public HTTPS. Each smp-server has its own credential.
+
+```mermaid
+flowchart LR
+  subgraph eth-host
+    Caddy["Caddy<br/>(public :443, basic auth)"]
+    Reth["Reth<br/>(127.0.0.1:8545)"]
+    Nimbus["Nimbus"]
+    Caddy --> Reth
+    Nimbus -- Engine API (jwt.hex) --> Reth
+  end
+  subgraph smp-host-1
+    S1["smp-server #1"]
+  end
+  subgraph smp-host-N
+    SN["smp-server #N"]
+  end
+  S1 -- HTTPS + Authorization --> Caddy
+  SN -- HTTPS + Authorization --> Caddy
+  Reth <-- Ethereum p2p --> internet
+  Nimbus <-- beacon sync --> internet
+```
+
+Sharing one Reth across **multiple operators** is **not** supported — collapses the RFC's two-server resolution privacy.
+
+**Reth + Nimbus**: Reth (execution layer) holds Ethereum state on ~260 GB pruned NVMe; Nimbus (consensus light client) follows beacon-chain headers. Paired via Engine API on `127.0.0.1:8551` with a shared `jwt.hex`. Recommended Reth flags:
+
+```bash
+reth node \
+  --http.addr 127.0.0.1 \
+  --http.api eth \                     # only eth namespace
+  --rpc.gascap 50000000 \              # cap gas per eth_call
+  --rpc.max-response-size 5242880 \    # 5 MB
+  --http.corsdomain none \
+  --authrpc.jwtsecret /opt/eth/jwt.hex \
+  --authrpc.addr 127.0.0.1 --authrpc.port 8551
+```
+
+**Caddy + Let's Encrypt + Basic auth** (Topology B):
+
+```caddy
+eth.simplex.chat {
+  basicauth {
+    smp-server-1 $2a$14$<bcrypt-hash-1>
+    smp-server-2 $2a$14$<bcrypt-hash-2>
+  }
+  log { format filter { wrap json; fields { request>headers>Authorization delete } } }
+  reverse_proxy 127.0.0.1:8545
+}
+```
+
+Caddy auto-fetches Let's Encrypt cert. Each smp-server has its own credential; revoking one = delete the line. `Authorization` stripped from access logs. Port 80 needed for the ACME HTTP-01 challenge (use TLS-ALPN-01 or DNS-01 to drop it). The threat being defended against is DoS (SNRC state is public); mTLS would be overkill. WireGuard/Tailscale are alternative network-layer approaches — both compatible with the plan.
+
+**Capacity.** One Reth+Nimbus box handles a realistic operator fleet by 10–1000× margin. Per-smp-server peak RSLV ≈ 1700 RPS (pessimistic); cache hit rate ≥ 95% → ~85 RPS cache miss per smp-server; 10 smp-servers → ~850 RPS aggregate cache miss reaching Reth; Reth `eth_call` throughput on warm NVMe ≈ 1k–10k RPS. Sizing: 8 vCPU, 32 GB RAM, 1 TB NVMe is comfortable. Scale-out path: more Reth+Nimbus pairs, smp-servers round-robin or shard.
+
+## Implementation
+
+**Order**:
+
+1. Protocol: party/SParty/PartyI, RSLV+tag, NAME+tag, NameRecord + helpers, version constants in `Transport.hs`.
+2. `verifyTransmission`/`verifyLoadedQueue`/`verifyQueueTransmission` `forwarded :: Bool` flag + `vc SResolver` clauses.
+3. Forwarded whitelist + `processCommand` branch + `incStat` move to `Stats.hs`.
+4. Env plumbing: `Server/Env/STM.hs`, `Server/Main.hs` INI parse, `Server/Main/Init.hs` template.
+5. Resolver subtree: `Eth/SNRC.hs` → `Eth/RPC.hs` → `Resolver.hs`.
+6. `NameResolverStats` sub-record + CSV log + Prometheus `names =` block.
+7. Replace stub in (3) with real `resolveName`.
+8. Tests.
+9. `protocol/simplex-messaging.md`: header version line 1 (`19 → 20`), sentence at line 86, version-history list (lines 93–105) v20 entry, TOC (lines 25–68) "Resolver commands" subsection, new section with ABNF + byte layout + error semantics, "Router security requirements" paragraph about names-role outbound HTTP, cross-ref `Transport.hs:226`.
+10. `CHANGELOG.md`: v6.6 entry.
+
+**Cabal** (`simplexmq.cabal`): bump `version: 6.6.0.0`. Add to `if !flag(client_library)` block: `http-client >=0.7 && <0.8`, `http-client-tls >=0.3 && <0.4`, `network-uri >=2.6 && <2.7`, `psqueues >=0.2.7 && <0.3`. Expose 4 new `Server.Names.*` modules in the same block. `crypton` already provides `Keccak_256`.
+
+**Files changed**:
+
+| File | Change |
+|---|---|
+| `Protocol.hs` | Resolver party + RSLV/NAME tags + version guards; `NameRecord` + newtypes + smart ctors; `nameRecBytes`/`parseNameRec`/`smpListPUpTo` helpers (no Encoding NameRecord instance); `LookupKey` parser-side cap |
+| `Transport.hs` | `namesSMPVersion = 20`; bump current/proxied SMP versions |
+| `Server.hs` | Thread `forwarded :: Bool`; `vc SResolver` clauses; whitelist (2132); Resolver branch in `processCommand` (1481); `closeServer` calls `closeNamesEnv`; CSV log (579–618); **remove** local `incStat` |
+| `Server/Env/STM.hs` | `namesConfig` field; `namesEnv` field; `newEnv` constructs `NamesEnv` with co-location guard |
+| `Server/Main.hs` | `[NAMES]` parse: `validateUrl`/`parseEthAddr`/`parseRpcAuth`; `scrubUrl` in logs |
+| `Server/Main/Init.hs` | `[NAMES]` block in default INI |
+| `Server/Stats.hs` | `incStat` moved here + exported; `NameResolverStats` sub-record + helpers; `rslvStats` field |
+| `Server/Prometheus.hs` | `names =` metric block |
+| `Server/Names.hs` (new) | Façade re-exports |
+| `Server/Names/Resolver.hs` (new) | All resolver types + cache + coalescing + `fetchOnceTimed` + `newNamesEnv[With]` + `closeNamesEnv` |
+| `Server/Names/Eth/RPC.hs` (new) | `EthRpcEnv`, `ethCallReal` with bounded body + concurrency semaphore + `Authorization` header |
+| `Server/Names/Eth/SNRC.hs` (new) | `EthAddress`, Keccak namehash, bounded ABI (8 invariants), `getRecord` with zero-owner detection |
+| `simplexmq.cabal` | Bump `6.6.0.0`; 4 new deps + 4 new modules in `if !flag(client_library)` block |
+| `protocol/simplex-messaging.md` | Header version, version-history v20 entry, new "Resolver commands" section |
+| `CHANGELOG.md` | v6.6 entry |
+
+## Testing
+
+`tests/SMPNamesTests/` registered in `tests/Test.hs:112–151`. Build only when `client_library = False`.
+
+1. **ProtocolEncodingSpec** — `nameRecBytes` ↔ `parseNameRec` round-trip; oversized fields rejected at parse; combined-list cap 8 enforced; negative `nrExpiry` rejected; canonical encoding byte-stable.
+2. **MaxSizeSpec** — max `NameRecord` encodes ≤ ~9 KB; `encodeTransmission v ≤ paddedProxiedTLength - 2`; `cbEncrypt` succeeds.
+3. **CommandTagSpec** — `"RSLV"`/`"NAME"` parse; v < 20 sessions reject `RSLV_` at parameter parser.
+4. **ForwardedGateSpec** — direct RSLV → `CMD PROHIBITED`; forwarded RSLV reaches handler.
+5. **ForwardedRslvSpec** — RSLV wrapped in PFWD reaches the handler end-to-end. **Test infra cost**: first protocol-level PFWD test; budget for `runProxiedSmpCommand` helper performing `PRXY`/`PKEY`/`PFWD` manually.
+6. **CacheSpec** — hit avoids RPC; TTL expiry forces re-fetch; bytes cap evicts before entries cap on large records; concurrent same-key callers issue one RPC; leader exception → all waiters get `Left _`, TMap entry removed; leader async-cancel → cleanup STM still runs.
+7. **AbiSpec** — encode/decode against pinned fixtures (`tests/fixtures/snrc/`); QuickCheck fuzz on random buffers ≤ `rpcMaxResponseBytes` must never crash.
+8. **NamehashSpec** — Keccak-256 reference vectors; assert Keccak ≠ SHA3-256.
+9. **MockRpcSpec** — fake HTTP server; missing → `EthHttpErr`; slow → `TimedOut`; multi-GB body truncated → `EthDecodeErr`. `rpcAuth = AuthBasic` sends correct header.
+10. **Uint256OverflowSpec** — `expiry > Int64.maxBound` → `EthDecodeErr`.
+11. **ZeroOwnerSpec** — `owner = 0x000...000` → `NotFound`.
+12. **StartupGuardSpec** — `allowSMPProxy + names.enable` aborts; `allow_dangerous_colocation = on` starts with warning.
+13. **UrlValidationSpec** — userinfo/scheme/host/port edge cases; rejects `https://` without `rpc_auth` for non-loopback.
+14. **EipChecksumSpec** — `parseEthAddr` accepts lower/upper; verifies mixed-case checksum; rejects typos.
+15. **AbiBoundsSpec** — each of 8 ABI invariants triggers `EthDecodeErr` without crash/allocation blow-up.
+
+Integration against real Reth+Nimbus mainnet deferred to ops.
+
+## Threat model, scope, coordination
+
+| Actor | Can | Cannot |
+|---|---|---|
+| Name server | See lookup-key bytes; see query timing; see Eth endpoint URL (operator-self) | See client IP/session; correlate clients across queries |
+| Compromised Eth endpoint | Poison this server's cache for one TTL window; see every lookup key the server queries | Bypass two-server agreement (client-side, out of scope) |
+| Adversarial client (high-rate unique keys) | Cache-thrash DoS; fill `Manager` connection pool up to `managerConnCount = 8` | Bypass `rpcMaxResponseBytes` or `fetchOnceTimed` |
+| Adversarial proxy (slow inner RSLVs) | Block other forwarded commands on that proxy connection up to `rpcTimeoutMs` per miss | Affect other proxy connections |
+| Operator with footgun config (https no auth, public Eth RPC) | (rejected at startup, or operator-acknowledged data leak) | — |
+
+Mitigations: caching + coalescing + `rpcTimeoutMs` + `rpcMaxResponseBytes` + `rpcMaxConcurrency`; co-location refused at startup; URL validation; Caddy + auth in front of Reth; Reth's own gas/size caps. Timing side-channels (cache-hit vs miss latency) not mitigated — flagged for post-MVP. State proofs deferred to post-MVP per RFC.
+
+**Cross-repo coordination.** The `simplex-chat` `ep/namespace` branch currently contains only the RFC commit — no agent-side wire-format code yet. This plan's wire format is validated only by simplexmq's own tests until a matching agent PR lands (structurally weak — encoder/decoder bugs are mutually consistent with themselves). Coordinate with the agent-side implementer **before merging** on: exact `NameRecord` field order and types; `LookupKey` namespace-prefix convention; error-code semantics; Part 1 SNRC contract `getRecord` ABI surface.

protocol/diagrams/duplex-messaging/queue-rotation-fast.mmd

@@ -5,13 +5,18 @@ sequenceDiagram
   participant S as Server<br>that has A's send queue<br>(B's receive queue)
   participant B as Bob
 
-  A ->> R': NEW: create new queue<br>(allow SKEY)
-  A ->> S: SEND: QADD (R'): send address<br>of the new queue(s)
+  A ->> R': NEW: create new queue (SKEY allowed)
+  A ->> S: SEND: QADD (R')
   S ->> B: MSG: QADD (R')
-  B ->> R': SKEY: secure new queue
-  B ->> R': SEND: QTEST
-  R' ->> A: MSG: QTEST
-  A ->> R: DEL: delete the old queue
-  B ->> R': SEND: send messages to the new queue
-  R' ->> A: MSG: receive messages from the new queue
-  
+  B ->> R: SEND: messages (also scheduled on R')
+  R ->> A: MSG: messages
+  B ->> R': SKEY: authorize B as sender
+  B ->> R': SEND: confirmation (establishes R' secret)
+  R' ->> A: MSG: confirmation (A secures R')
+  B ->> R': SEND: held copies (deduped), then new messages
+  R' ->> A: MSG: messages
+  B ->> R: SEND: remaining tail, then QEND
+  R ->> A: MSG: QEND
+  B ->> R': SEND: QEND
+  R' ->> A: MSG: QEND
+  A ->> R: DEL: delete the current queue

protocol/simplex-messaging.md

@@ -1,4 +1,4 @@
-Version 19, 2025-01-24
+Version 21, 2026-07-05
 
 # Simplex Messaging Protocol (SMP)
 
@@ -67,6 +67,9 @@ Version 19, 2025-01-24
     - [Queue deleted notification](#queue-deleted-notification)
     - [Error responses](#error-responses)
     - [OK response](#ok-response)
+  - [Resolver commands](#resolver-commands)
+    - [Resolve name command](#resolve-name-command)
+    - [Name record response](#name-record-response)
 - [Transport connection with the SMP router](#transport-connection-with-the-SMP-router)
   - [General transport protocol considerations](#general-transport-protocol-considerations)
   - [TLS transport encryption](#tls-transport-encryption)
@@ -83,7 +86,7 @@ It's designed with the focus on communication security and integrity, under the
 
 It is designed as a low level protocol for other application protocols to solve the problem of secure and private message transmission, making [MITM attack][1] very difficult at any part of the message transmission system.
 
-This document describes SMP protocol version 19. Versions 1-5 are discontinued. The version history:
+This document describes SMP protocol version 20. Versions 1-5 are discontinued. The version history:
 
 - v1: binary protocol encoding
 - v2: message flags (used to control notifications)
@@ -103,6 +106,8 @@ This document describes SMP protocol version 19. Versions 1-5 are discontinued.
 - v17: create notification credentials with NEW command
 - v18: support client notices in BLOCKED error
 - v19: service subscriptions to messages (SUBS, NSUBS, SOKS, ENDS, ALLS commands)
+- v20: public namespaces resolver (RSLV command, RNAME response) — direct or forwarded via PFWD
+- v21: server public information in handshake
 
 ## Introduction
 
@@ -424,6 +429,8 @@ Simplex messaging router implementations MUST NOT create, store or send to any o
 
 - Any other information that may compromise privacy or [forward secrecy][4] of communication between clients using simplex messaging routers (the routers cannot compromise forward secrecy of any application layer protocol, such as double ratchet).
 
+Routers with the names role make outbound HTTP calls to a backing resolver service (the reference implementation is `scripts/resolver/snrc-resolve.py`, which in turn makes JSON-RPC calls to an Ethereum endpoint) to read `NameRecord` data; the lookup key reaches that resolver and its upstream RPC endpoint. Operators MUST run both the resolver process and its upstream RPC endpoint themselves (loopback Reth + Nimbus, or a self-hosted central deployment) — sharing them across multiple operators collapses the two-server privacy property because the resolver / RPC operator would see every lookup key across all of them. The names role and the SMP-proxy role MUST NOT be enabled on the same router by default: a client forwarding `RSLV` through a proxy that is also the names router would expose both its connection and the lookup key to one operator, collapsing the two-server privacy property. (Resolution itself runs on a forked thread, so a slow `RSLV` does not serialise other forwarded commands on the session.)
+
 ## Message delivery notifications
 
 Supporting message delivery while the client mobile app is not running requires sending push notifications with the device token. All alternative mechanisms for background message delivery are unreliable, particularly on iOS platform.
@@ -1422,6 +1429,120 @@ When the command is successfully executed by the router, it should respond with
 ok = %s"OK"
 ```
 
+### Resolver commands
+
+Resolver commands implement public-namespace name resolution on the names-role
+router. A names router translates an opaque lookup key (such as `alice` or
+`alice.simplex.eth`) into a `NameRecord` carrying the channel and contact links
+the named party publishes.
+
+**Direct or forwarded.** RSLV is an unauthenticated command accepted both
+directly from a transport client and inside a `PFWD` block via the SMP proxy;
+the client chooses. Forwarded delivery preserves the two-server privacy property
+of the resolver design: the names router sees the lookup key but never the
+client IP, session, or identity, while the proxy router sees the client
+connection but cannot read the encrypted lookup key inside the forwarded
+transmission. Direct delivery is simpler but exposes the client's connection to
+the names router, so clients SHOULD prefer the forwarded path when proxying is
+available.
+
+**Backing store.** This protocol does not prescribe where the names router
+reads `NameRecord` from. The reference implementation forwards each RSLV to a
+companion REST resolver process (`scripts/resolver/snrc-resolve.py`) that
+queries the SNRC contract on Ethereum; alternative backings (different chains,
+DHT, etc.) are valid as long as they expose the documented HTTP shape (`GET
+/resolve/<name>` returning a `NameRecord` on 200, 404 / 400 for unknown names
+or TLDs, 502 for upstream RPC failures) or substitute a different transport
+while still returning a `NameRecord` matching the encoding below.
+
+#### Resolve name command
+
+The `RSLV` command carries the canonical fully-qualified name directly as the
+payload (not JSON):
+
+```abnf
+rslv = %s"RSLV" SP domain   ; domain = canonical name as non-space bytes, consuming the remainder of the transmission
+```
+
+`domain` is the UTF-8 canonical fully-qualified name with the TLD always
+explicit (e.g. `privacy.simplex`, `test.testing`, `example.com`), bounded to
+253 bytes.
+
+**Server-side validation.** The names router parses `domain` as a
+fully-qualified name (TLD required — bare labels are rejected) and forwards it
+to the configured backing resolver, which is the source of truth for which
+on-chain registry maps to each TLD.
+
+The names router responds with either an `RNAME` response carrying the resolved
+record, or an `ERR NAME` error whose subcode a client iterating across several
+configured servers can act on distinctly:
+
+| Response | Condition | Client action |
+|---|---|---|
+| `RNAME` | record resolved | use it |
+| `ERR NAME NOT_FOUND` | name not registered, unknown TLD, or malformed name | authoritative "no such name" — stop |
+| `ERR NAME NO_RESOLVER` | this router has no resolver (names role not enabled) | skip this server, try the next |
+| `ERR NAME RESOLVER <detail>` | transient failure: backing resolver error (upstream 5xx, transport, timeout, decode) | transient — retry or surface, do not treat as "not found" |
+
+A client SHOULD NOT broadcast a `name` to further servers after a name-capable
+router has answered (`NOT_FOUND` or `RESOLVER`), since that router has already
+seen the lookup key; `NO_RESOLVER` discloses nothing about the name beyond the
+fact that this router cannot resolve, so iterating past it is safe.
+
+#### Name record response
+
+The `RNAME` response carries a JSON-encoded record as the payload:
+
+```abnf
+rname = %s"RNAME" SP json-bytes   ; json-bytes consumes the remainder of the transmission
+```
+
+`json-bytes` MUST be a UTF-8 JSON object with the following schema:
+
+| Field | JSON type | Constraints |
+|---|---|---|
+| `name` | string | ≤ 255 bytes UTF-8 |
+| `nickname` | string | ≤ 255 bytes UTF-8; senders MUST emit the empty string `""` when unset |
+| `website` | string | ≤ 255 bytes UTF-8; same empty-string-when-unset rule |
+| `location` | string | ≤ 255 bytes UTF-8; same empty-string-when-unset rule |
+| `simplexContact` | array of strings | each a SimpleX contact link (primary first); empty array `[]` when unset |
+| `simplexChannel` | array of strings | each a SimpleX channel link (primary first); empty array `[]` when unset |
+| `eth` | string or null | ≤ 255 bytes UTF-8; senders MUST emit `null` when unset; receivers MUST also accept absent keys as unset |
+| `btc` | string or null | ≤ 255 bytes UTF-8; same null / absent rules |
+| `xmr` | string or null | ≤ 255 bytes UTF-8; same null / absent rules |
+| `dot` | string or null | ≤ 255 bytes UTF-8; same null / absent rules |
+| `owner` | string | `"0x"` followed by 40 lowercase hex characters (20 raw bytes) |
+| `resolver` | string | `"0x"` followed by 40 lowercase hex characters; the resolver contract address that produced the record |
+
+Text fields (`nickname`, `website`, `location`) use the empty string `""` as
+the "unset" sentinel: a backing resolver with no value for the field MUST emit
+an empty string, not JSON `null` and not an absent key. Link fields
+(`simplexContact`, `simplexChannel`) are arrays, primary link first, and use the
+empty array `[]` when unset. Coin fields (`eth`, `btc`, `xmr`, `dot`) use JSON
+`null` as the "unset" sentinel and MAY also be absent from the object entirely.
+
+The backing resolver filters records that are expired or otherwise unavailable
+(the names router then returns `ERR NAME NOT_FOUND` to the client), so the wire
+format carries no expiry field. Testnet-vs-mainnet status is derived from the
+queried TLD rather than an in-record flag.
+
+Receivers MUST tolerate extra unknown fields (forward-compatibility for future
+field additions). Adding a required field is a breaking change requiring an
+SMP version bump.
+
+**Field order is not significant.** Receivers parse JSON by key name, so object
+key order, insignificant whitespace, and number formatting carry no meaning;
+records are interpreted by decoded value, never compared byte-for-byte. Peers
+MUST NOT rely on a byte-canonical form — a different resolver or server may emit
+the same record with different key order or spacing. This order-independence is
+what makes the format forward-compatible (see the unknown-field rule above).
+
+**Wire-size budget.** The names router caps the resolver response it will
+accept (`resolver_max_response_bytes`, ≤ 16000 bytes, the default) so the
+re-encoded `RNAME` stays within the SMP proxied transmission budget of 16224
+bytes; a response over the cap is rejected as `ERR NAME RESOLVER`. The link
+arrays are bounded by this overall budget rather than a fixed per-field count.
+
 ## Transport connection with the SMP router
 
 ### General transport protocol considerations

rfcs/2026-07-11-service-rpc.md

@@ -0,0 +1,114 @@
+---
+Proposed: 2026-07-11
+Protocol: agent-protocol (new version)
+Depends on: 2026-07-12-address-pqdr-keys
+---
+
+# One-off requests to service addresses
+
+Implementation plan: to follow, after this and the address-DR RFC are reviewed.
+
+## Problem
+
+Client applications need to interact with services, for example: badge issuance, directory requests, telemetry submissions, blockchain reads and writes, LLM calls. The only communication primitive available today is a duplex connection, so each of these interactions requires the full connection procedure - creating queues, key agreement, double ratchet initialization - and leaves persistent state on both sides: queues, ratchet state, connection records, message history.
+
+This is the wrong primitive for most service interactions:
+
+1. Cost. To send the first request to a not yet connected service, the client and the service exchange multiple commands across two servers. For "search the directory" all of it is overhead. The setup cost also creates an incentive to keep connections open, and a service with N users who used it once permanently holds N sets of queues and ratchet states.
+
+2. Privacy. A connection is a stable pairwise pseudonym. If a service were to use a duplex connection, it could link all requests made over it into a profile: search history in the directory, blockchain operations linked even when different on-chain keys are used, telemetry that becomes longitudinal tracking. The client also accumulates history that can be recovered from the device. Where continuity is needed, it can be provided in the application protocol (e.g., a token included in requests), without a transport-level identity.
+
+3. Encryption. Messages sent to contact addresses outside an established connection have a single layer of X25519 encryption, with no post-quantum protection and no forward secrecy. This is not acceptable for service requests.
+
+In-app service addresses should be stored as names resolving to links via the existing addressing layer (server host in the link authority, current link data retrieved with `LGET`), so that service links can be changed without redeploying the apps. Name resolution is already supported, and out of scope.
+
+## Security objectives
+
+1. Requests from the same client must not be linkable to each other by the service or by servers, and no long term state is created on either side in the transport layer.
+2. Post-quantum resistant end-to-end encryption of requests and replies.
+3. Reply authenticity must be verifiable against the link; substitution, replay, dropping or reordering of replies by servers must be detectable.
+4. A repeated request for the same operation must not be executed twice.
+
+## Solution
+
+A service address is an ordinary short-link contact address. The client sends one request to the address queue and receives replies in a reply queue it creates for the request. The double ratchet is established from the address's published keys (see the address-DR RFC): the request is the first ratchet message, and replies are subsequent ratchet messages. So a request-response exchange is a short-lived one-directional double ratchet connection, established from the first message and removed after the last.
+
+The exchange:
+
+1. Retrieve the address link data (`LGET`, via proxy when IP protection is needed): the root key, the identity key, the prekey with its id, and the KEM key.
+2. Create a reply queue (`NEW`, subscribed).
+3. Establish the sending ratchet from the published keys (`pqX3dhSnd`, `initSndRatchet`). Build the request: the reply queue, the requester's X3DH parameters, and the payload encrypted under the ratchet. Encrypt the whole request to the address queue and send it once (unauthenticated `SEND`, via proxy when IP protection is needed). There is no transport retry; a reply is the success signal, and a hard error fails the request.
+4. The service establishes the receiving ratchet from its private keys and the request's X3DH parameters (`pqX3dhRcv`, `initRcvRatchet`), decrypts the payload, and delivers it to the service application. To reply it creates a send connection with the ratchet and sends reply messages to the reply queue, each encrypted under the ratchet.
+5. The client decrypts and delivers each reply message to the application. The first reply message returns from the request; later reply messages are delivered through a callback the application registered. The exchange ends on a reply marked final. The client deletes the reply queue and the ratchet on the final message, the deadline, or when the application cancels.
+
+How this meets the objectives:
+
+1. Unlinkability: fresh X3DH keys and a fresh reply queue per request; the sender's IP address and session are protected by existing private routing; the reply queue and both ratchets are removed after the exchange; nothing is shared between two requests.
+2. Encryption: the double ratchet with its sntrup761 KEM, from the first message.
+3. Authenticity: the ratchet is established against the identity key committed by the link hash, so a decryptable reply proves it came from the address owner; the ratchet message numbering detects dropped and reordered replies. No separate signature is needed.
+4. Single execution: the service identifies a request by the hash of its decrypted payload and, within a fixed retention period, re-sends the stored replies for a repeated request without running the operation again.
+
+## Design
+
+Syntax uses [ABNF][1] with [case-sensitive strings extension][2]. `SMPQueueInfo`, `agentVersion`, and the X3DH and ratchet types are as in the [agent protocol](../protocol/agent-protocol.md) and `Crypto.Ratchet`.
+
+### Correlation and chat
+
+A reply is connected to its request by the reply queue: each request has its own reply queue, and every message in that queue is a reply to that request. The request hash (of the decrypted payload) is used only for idempotency. The application sets an id inside the payload to make two requests the same operation or different ones; the agent does not read it.
+
+Both ends are chat bots on the chat library over the agent. The chat library serializes a service command into the request payload and deserializes the responses; the agent transports them, establishes and removes the ratchet, and correlates by reply queue.
+
+### Request
+
+A new agent envelope, shaped like `AgentConfirmation` (X3DH parameters to establish the ratchet, plus a body encrypted under it):
+
+```abnf
+agentRequest = agentVersion %s"Q" replyQueues prekeyId sndE2EParams encRequest
+replyQueues = length 1*SMPQueueInfo ; the first is used; more are for redundancy
+prekeyId = shortString ; the published prekey used, from link data
+sndE2EParams = <requester Snd X3DH parameters, see address-DR RFC>
+encRequest = <ratchet-encrypted request payload>
+```
+
+The whole `agentRequest` is encrypted to the address queue with the per-queue layer and sent with `SEND`, as an invitation is today. The reply queue keys and the X3DH parameters are not visible to servers. A request must fit one message; a larger payload is an XFTP file description in the payload.
+
+The request hash is the SHA3-256 of the decrypted payload - the same bytes on both sides. There is no transport retry; a hard error (`AUTH`, `QUOTA`) fails the request, and the application decides whether to send a new one.
+
+### Replies
+
+The service creates a send connection with the ratchet and sends reply messages to the reply queue, each encrypted under the ratchet. A reply message uses a new agent envelope:
+
+```abnf
+agentResponse = agentVersion %s"P" final responses
+final = %s"T" / %s"F" ; T - no more reply messages follow
+responses = length 1*responseItem ; non-empty list of application responses
+responseItem = largeString ; opaque application response
+```
+
+Each message includes a list of responses, so responses known together are sent in one message and responses that become known over time are sent in separate messages. The message is encrypted and numbered by the ratchet, which authenticates it against the committed identity key and detects dropped or reordered messages; no separate signature is used.
+
+The first reply message returns from the request. Later reply messages are delivered through the callback the application registered with the request, while the process runs. The exchange ends on a message with `final = T`. The client deletes the reply queue and the ratchet on that message, on the deadline, or when the application cancels. Deleting the reply queue stops further replies. The transport keeps no exchange across a client restart; the application keeps its own state and sends a new request when it needs to.
+
+### Rejection
+
+The service refuses a request with the `AgentRejection` envelope from the [communicating rejection RFC](../../simplex-chat/docs/rfcs/2024-03-22-communicating-reject.md), sent to the reply queue under the ratchet, with an opaque application reason. The same envelope communicates refusal of a connection request, where today it is dropped silently. A rejection ends the exchange like a final reply.
+
+### Idempotency
+
+The service keeps, for a fixed retention period it chooses (1 to 24 hours, in service configuration, not in link data), the request hash, the ordered response messages it produced, and the reply queues and ratchets subscribed under that hash. A repeat request with the same hash does not reach the service application:
+
+- while the first request is being answered, the repeat establishes its own ratchet and reply queue, is added to the record, receives the responses already produced, and receives each later response too.
+- after the operation completed, the repeat receives the whole stored sequence of responses, re-encrypted under its own ratchet.
+
+The stored responses are the application response bytes, not the ratchet ciphertext, because a repeat establishes a new ratchet and the responses are re-encrypted for it. This gives single execution over at-least-once delivery. After the retention period a request with the same hash is a new operation and runs again.
+
+### Out of scope
+
+- Recovery across restart: the transport keeps no exchange across a client restart; the application persists its own state and sends a new request when it needs to.
+- Service-initiated messages: there is no standing channel; use a connection where the service must reach the client without a request.
+- Abuse protection beyond existing queue quotas: services can require application-level credentials (e.g., a badge) in the request payload; rate limiting is a separate discussion.
+- Scaling request reception: a single address queue bounds service throughput; distributing reception across multiple queues or relays (the existing `relays` field in contact link data) is a separate question, but it would fit well with name resolving to multiple addresses, both for redundancy, reliability and higher throughput.
+- Name resolution: existing addressing layer.
+
+[1]: https://tools.ietf.org/html/rfc5234
+[2]: https://tools.ietf.org/html/rfc7405

rfcs/2026-07-12-address-pqdr-keys.md

@@ -0,0 +1,83 @@
+---
+Proposed: 2026-07-12
+Protocol: agent-protocol (new version)
+---
+
+# Establishing the double ratchet from address data
+
+## Problem
+
+A contact address receives a connection request as an `AgentInvitation` message, encrypted only with the per-queue X25519 layer. The double ratchet is established later: the address owner joins the requester's connection request, generates its X3DH keys, and sends them in the confirmation. So the first message to an address - the invitation and the profile in it - is not under the double ratchet, and has no post-quantum protection.
+
+The cause is that the address owner's X3DH contribution is generated per request and sent in the confirmation, so it cannot exist before the requester's first message.
+
+## Solution
+
+Publish the address owner's X3DH contribution in the address link data, so a requester can establish the double ratchet in its first message. The requester runs the existing `pqX3dhSnd` against the published keys, initializes a sending ratchet, and encrypts its first message under it. The owner runs the existing `pqX3dhRcv` against its stored private keys and the requester's X3DH keys from the message, initializes a receiving ratchet, and decrypts it.
+
+Publish the owner's X3DH contribution - two X448 keys and an optional sntrup761 KEM key, with the e2e version range - as one bundle in the mutable contact user data, signed by the root key. The bundle is the existing `RcvE2ERatchetParamsUri` type that a one-time invitation already advertises, with an id for rotation.
+
+This is backward compatible. A requester that does not use the published bundle sends a current `AgentInvitation` with its own X3DH keys, and the owner does what it does today: generates fresh X3DH keys and sends them in the confirmation. The owner branches on whether the incoming message uses the published bundle.
+
+Three properties follow. The first message, including the profile, is under the double ratchet, which closes the profile gap and gives it post-quantum protection through the ratchet's sntrup761 KEM. A decryptable message proves the sender established X3DH against the root-signed keys, so it authenticates the address owner without a separate signature. And because the bundle is in mutable data, an existing address can advertise the double ratchet by updating its mutable data - no new link.
+
+## Design
+
+Syntax uses [ABNF][1] with [case-sensitive strings extension][2]. Key and ratchet types are as in `Crypto.Ratchet` and the [agent protocol](../protocol/agent-protocol.md); all DH keys are X448, the KEM is sntrup761.
+
+### Published keys in link data
+
+The owner's X3DH contribution is a ratchet-keys bundle appended to the mutable contact user data, signed by the root key. Nothing is added to the immutable fixed link data:
+
+```abnf
+userContactData =/ ratchetKeys ; appended, ignored by earlier versions
+ratchetKeys = %s"0" / (%s"1" ratchetKeyId e2eParams)
+ratchetKeyId = shortString ; identifies this bundle, changes on rotation, echoed in the request
+e2eParams = <RcvE2ERatchetParamsUri: e2e version range, two X448 keys, optional sntrup761 key>
+```
+
+`e2eParams` is the existing `RcvE2ERatchetParamsUri` - the same type a one-time invitation advertises - so a requester reads it, negotiates the concrete e2e version against its own range, and runs `pqX3dhSnd` against it, exactly as it does for an invitation. The KEM key is optional (the params' KEM field is a `Maybe`), controlled by the address's initial-keys mode, the same 3-way choice as invitations: advertise the KEM (post-quantum from the first message), advertise X448-only but still support post-quantum if the requester proposes its own KEM (one message later, avoiding the ~1158-byte key in link data), or no post-quantum.
+
+The owner keeps the private side of each bundle - the two X448 private keys and, when PQ is on, the KEM keypair - indexed by `ratchetKeyId`. On rotation with `LSET` it publishes a new bundle with a new `ratchetKeyId` and keeps the previous private keys for a window covering queue message retention, so a request that used a just-rotated bundle still decrypts. Because the bundle is in mutable data, an existing address advertises the double ratchet by updating its mutable data - no new link, no re-creation.
+
+### Request confirmation
+
+A requester that uses the published keys establishes the sending ratchet before its first message, so it sends that message as a confirmation, not an invitation - the same envelope a joining party sends in a connection. The confirmation gains an optional `ratchetKeyId` naming the bundle the requester used, so the owner selects the matching private keys:
+
+```abnf
+agentConfirmation =/ ratchetKeyId ; the bundle the requester used, echoed; absent on other confirmations
+```
+
+The confirmation holds the requester's Snd X3DH parameters (so the owner runs `pqX3dhRcv`) and, encrypted under the ratchet, the first message. A confirmation with `ratchetKeyId` on a contact address takes the published-key path; an `AgentInvitation`, as today, takes the current path where the owner generates fresh X3DH keys and returns them in its own confirmation. A connection-request URI is unchanged: it advertises the requester's Rcv parameters and must not include Snd parameters.
+
+### Establishing the ratchet
+
+Requester:
+
+1. Retrieve link data (`LGET`), read the bundle - its `ratchetKeyId` and `e2eParams` (`RcvE2ERatchetParamsUri`) - and negotiate the concrete e2e version against its own range.
+2. `generateSndE2EParams` for its own X3DH contribution - encapsulating to the bundle's KEM if it advertises one, or proposing its own KEM if the requester wants post-quantum and the bundle is X448-only.
+3. `pqX3dhSnd` against the bundle's parameters, then `initSndRatchet` - the sending ratchet.
+4. Encrypt the first message under the ratchet, and send a confirmation with its Snd parameters and `ratchetKeyId`.
+
+Owner:
+
+1. On a confirmation with `ratchetKeyId` on a contact address, select the private X3DH keys and, if any, KEM keypair by `ratchetKeyId` (current or a retained previous generation).
+2. `pqX3dhRcv` against the requester's Snd parameters with those private keys, then `initRcvRatchet` - the receiving ratchet. Decrypting the first message advances the ratchet and gives it a send side, so the owner can reply.
+3. Decrypt, and reply under the ratchet.
+
+A request whose `ratchetKeyId` is no longer retained cannot be decrypted; the owner does not learn the requester or its reply address, and the requester's attempt fails at its own timeout.
+
+### Authentication
+
+The ratchet-keys bundle is in the mutable link data, signed by the root key. A decryptable message proves the sender established X3DH against those root-signed keys: an SMP server cannot substitute them without forging the root signature (`decryptLinkData` verifies it), which is the X3DH anti-substitution property. Where a message today relies on a separate signature over its content for authenticity, this establishment provides it, and the signature is not needed. The root Ed25519 key is the address's signing identity; the X3DH keys are separate DH keys (X448), and X3DH is over crypto_box, so deniability is preserved. A malicious server can still serve an older but validly-signed bundle (rollback to a retired generation); this is bounded by the retention window and by the ratchet advancing after the first message, and a per-key signature would not prevent it. Reusing a bundle across requesters is consistent with the address already being a shared identifier.
+
+## Uses
+
+- Invitations to an address, and the profile in them, are under the double ratchet from the first message.
+- An existing address gains the double ratchet when the app updates its mutable link data (`LSET`, with the user's confirmation and current profile, combined with the full→short address migration); no new link is issued.
+- The service RPC (see the RPC RFC) establishes the ratchet this way to send the request as the first ratchet message.
+
+This RFC depends on nothing else here. It replaces the need for the PQ-queue RFC in the address case, because the ratchet provides post-quantum protection for the first message; the PQ-queue RFC remains for first messages that do not establish a ratchet.
+
+[1]: https://tools.ietf.org/html/rfc5234
+[2]: https://tools.ietf.org/html/rfc7405

rfcs/2026-07-12-queue-pq-encryption.md

@@ -0,0 +1,42 @@
+---
+Proposed: 2026-07-12
+Protocol: smp-client (new version)
+---
+
+# Post-quantum encryption of the SMP queue layer
+
+## Problem
+
+A message sent to a queue outside an established double ratchet has one layer of end-to-end encryption: NaCl crypto_box over an X25519 DH secret. The sender generates an ephemeral X25519 key, computes the secret with the recipient's per-queue DH key, and puts its ephemeral key in the message public header (`agentCbEncryptOnce`). This layer protects invitations, confirmations, and the profile sent with them.
+
+It is not post-quantum. An adversary that records this traffic and later has a quantum computer can recover the X25519 secret and decrypt it. The double ratchet adds a post-quantum KEM once it is established, but the first message to a queue, before the ratchet, has only X25519.
+
+This RFC adds post-quantum protection to the single-shot queue encryption itself, for cases that do not establish a double ratchet from the first message. Where a double ratchet is established from the first message (see the address-DR RFC), the ratchet provides post-quantum protection and this layer is not needed.
+
+## Solution
+
+Extend the single-shot queue encryption to a hybrid X25519 + sntrup761 scheme, in a new SMP client version. The recipient publishes a KEM encapsulation key alongside its per-queue DH key. The sender encapsulates to it, combines the KEM shared secret with the X25519 DH secret, and encrypts the body with the combined secret. The KEM ciphertext travels in the message public header next to the ephemeral X25519 key.
+
+Recording the traffic and breaking X25519 later is not sufficient: without breaking sntrup761 as well, the combined secret is not recoverable.
+
+## Design
+
+The message public header (`PubHeader`) gains a hybrid variant, selected by a version and a tag, so older senders and the empty-header case are unchanged:
+
+```abnf
+smpPubHeaderHybrid = smpClientVersion %s"2" senderPublicDhKey kemCiphertext
+senderPublicDhKey = length x509encoded ; sender ephemeral X25519 key
+kemCiphertext = largeString ; sntrup761 ciphertext, 1039 bytes
+```
+
+The secret combines both shared secrets, and the body is encrypted with NaCl secret_box (the DH-only path uses crypto_box today; the combined secret is no longer a plain DH result, so it is used as a secret_box key), padded to the same lengths:
+
+```
+secret = HKDF(dh(recipient key, sender ephemeral key) || KEM shared secret)
+```
+
+The recipient's KEM encapsulation key is distributed the same way its per-queue DH key is today - in the queue address for a connection request, and in link data for a short link. The KEM ciphertext is stored the same way the ephemeral DH key is: in the public header, readable by the destination server (and not by the proxy with proxied sending), which cannot derive the secret without the recipient's KEM private key.
+
+The recipient stores the computed secret the way the per-queue DH secret is stored on receiving the first message (`setRcvQueueConfirmedE2E`), and reuses it for later messages on the queue.
+
+Sizes: the KEM ciphertext is 1039 bytes and the encapsulation key 1158 bytes. Link data user data is padded to 13784 bytes, so the key fits with application data. This RFC is independent of the RPC, SSND, and address-DR RFCs.

rfcs/2026-07-12-smp-secure-send.md

@@ -0,0 +1,55 @@
+---
+Proposed: 2026-07-12
+Protocol: smp (new version)
+---
+
+# SSND: combined secure-and-send command
+
+## Problem
+
+Two SMP flows secure a messaging queue and then immediately send the first message to it, as two commands and two round trips:
+
+- The fast connection handshake: the joining party secures the queue with `SKEY`, then sends the confirmation with `SEND`.
+- Any first send to a sender-securable queue where the sender both secures it and delivers the first message.
+
+The two commands express one intent - "this is my key, and here is my first message" - so they can be one command and one round trip. The combination must be idempotent, because the first send is retried on network failure and a queue is often secured before the response is known. `SKEY` is already idempotent (a repeat with the same key succeeds). `SEND` is not, so a naive combination would deliver a duplicate message on retry.
+
+## Solution
+
+A new command `SSND` combines `SKEY` and `SEND` in one transmission, idempotent in both parts:
+
+- Key part: as `SKEY` - a repeat with the same key succeeds, a different key fails with `AUTH`.
+- Send part: the server keeps the hash of the message until it is acknowledged, and reports a repeat of the same message as delivered without delivering it again.
+
+The server-side hash covers the common case, when the retry arrives before the message is acknowledged. A retry that arrives after the acknowledgement is delivered as a duplicate and discarded by the receiving agent by message hash, as duplicate messages are discarded today.
+
+## Design
+
+Syntax uses [ABNF][1] with [case-sensitive strings extension][2]. `senderAuthPublicKey`, `msgFlags` and `smpEncMessage` are as in the [SMP protocol](../protocol/simplex-messaging.md).
+
+```abnf
+secureSend = %s"SSND " senderAuthPublicKey SP msgFlags SP smpEncMessage
+senderAuthPublicKey = length x509encoded
+```
+
+`SSND` is a sender command, authorized with the key it sets, and accepted only on messaging-mode queues (`QMMessaging`), where the sender can secure the queue. The server responds `OK` or `ERR`.
+
+Server processing:
+
+1. Secure the queue with the key, as `SKEY`. A repeat with the same key succeeds; a different key returns `AUTH`.
+2. If the queue holds an unacknowledged message whose stored hash equals the hash of this message, respond `OK` without storing it again.
+3. Otherwise store the message, keep its hash with the queue until the message is acknowledged, and deliver it.
+
+The stored hash is one value per not-yet-acknowledged queue message. It is removed when the message is acknowledged. All queue store backends (in-memory, journal, PostgreSQL) keep it.
+
+`SSND` composes with the proxy protocol without change: `proxySMPCommand` forwards any sender command through `PFWD`/`RFWD`, so `SSND` is proxied as `SEND` and `SKEY` are today.
+
+## Uses
+
+- The fast connection handshake replaces `SKEY` then the `SEND` confirmation with one `SSND`.
+- The service RPC response (see the RPC RFC) secures the reply queue and sends the first reply with one `SSND`.
+
+This RFC is independent of the RPC, PQ-queue, and address-DR RFCs and can be implemented on its own.
+
+[1]: https://tools.ietf.org/html/rfc5234
+[2]: https://tools.ietf.org/html/rfc7405

rfcs/2026-08-09-fast-queue-rotation.md

@@ -0,0 +1,97 @@
+---
+Proposed: 2026-08-09
+Protocol: agent-protocol v8
+Diagram: ../protocol/diagrams/duplex-messaging/queue-rotation-fast.svg
+---
+
+# Fast queue rotation
+
+## Problem
+
+In the current rotation the peer returns `QKEY` to the initiator over the initiator's current
+receiving queue. When that queue's server is unavailable the rotation cannot complete, so a client
+cannot move away from a failed server.
+
+## Solution
+
+Both the current rotation and v8 add a queue, deliver to both queues while the rotation is in
+progress, and remove the old queue; the recipient drops duplicates in both. The main difference is where
+the new queue's secret is established. In the current rotation it is established over the current
+queue, by `QKEY`, so it cannot complete when the current server is down. In v8 the peer establishes the
+new queue's secret over the new queue itself — a confirmation it sends on R' — so establishing the
+secret no longer depends on the current queue, and the rotation completes even when the current server
+is down.
+
+v8 also starts writing to both queues earlier: from the moment the queue is added, including the
+current queue's not-yet-delivered backlog. So the initiator adds the new queue with `QADD`; from that
+point the peer writes every message to both the current queue and R'. Once R' is secured the peer
+writes new messages to it alone, while the current queue delivers whatever was already scheduled on it
+and a final `QEND`, and is then removed. Because the recipient drops duplicates, neither the order of
+arrival nor which queue carries a message matters, provided each message arrives on at least one queue
+— with one exception, the confirmation, which is always the first message on R'. A dead new queue does
+not stop delivery either, because the current queue keeps delivering until R' is secured.
+
+Roles: A initiates (its receiving queue rotates; A receives on the new queue R'). B is the peer (B
+holds the sending queue to A, secures R', and delivers to both).
+
+Sequence:
+
+    A -> R'       : create new queue (messaging mode, SKEY allowed)
+    A -> S -> B   : QADD(R')          (over A's sending queue; A's current server untouched)
+    B             : from QADD, schedule every message and the current backlog on both queues
+    B -> current  : deliver the scheduled messages (R' holds its copies while securing)
+    B -> R'       : SKEY              (authorize B as sender)
+    B -> R'       : confirmation      (empty; establishes R' secret; first message on R')
+    B -> R'       : deliver R''s held copies (A dedups), then new messages to R' only
+    B -> current  : deliver the remaining tail, then QEND(current)
+    B -> R'       : QEND(current)
+    A             : on QEND, delete the current queue; keep receiving on R'
+
+## Confirmation
+
+The confirmation is the only message a recipient can read on a queue that is not yet secured, and it
+establishes the queue's shared secret without depending on the current queue. Because a data message
+that reached R' before the confirmation could not be read, the confirmation is the first message the
+peer sends on R', and the peer does not start ordinary delivery on R' until the confirmation has been
+sent.
+
+The confirmation body is empty: both parties already know each other, so no profile or reply queue is
+sent. It is sealed by the queue's box (keyed by the shared secret being established) and is not
+additionally encrypted with the double ratchet, so rotation does not advance the message ratchet.
+
+## Termination
+
+`QEND` names a queue to remove and is delivered on both queues. On receipt the recipient deletes the
+named queue; on send the peer removes its sending queue of that address. `QEND` is a general
+queue-removal message — the peer can remove either queue with it — so on the wire a rotation is the
+addition of a queue (`QADD`) and the later removal of the replaced one (`QEND`), each an ordinary
+operation on the queue set rather than a `QTEST`-style completion. Delivering `QEND` on the removed
+queue is best effort; the copy on the surviving queue removes it and reaches the recipient even when
+the removed server is dead.
+
+## Per-queue secret
+
+R' secret is a fresh Diffie-Hellman between the peer's queue key, sent in the confirmation header, and
+the initiator's R' key. It does not depend on any current queue, so redundancy of current queues is
+unaffected.
+
+## Compatibility
+
+Fast rotation runs only when the connection's agreed agent protocol version is 8 or higher; the peer
+chooses it. Otherwise the `QKEY`/`QUSE` exchange is used. `QEND` is defined at version 8 and is only
+sent during fast rotation, so peers below version 8 never receive it.
+
+    new A / new B  : fast (QADD, confirmation on R', QEND)
+    new A / old B  : slow (old B returns QKEY; new A keeps the QKEY/QUSE handling)
+    old A / new B  : slow (agreed version below 8; new B returns QKEY)
+    old A / old B  : slow
+
+The recipient does not choose by version; it reacts to whichever message arrives — `QKEY`, or a
+confirmation on R' followed later by `QEND`.
+
+## Dead current server
+
+The initiator keeps reading messages on the new queue and removes the current queue when `QEND`
+arrives there, without waiting for the current server. Nothing is lost, because every message is
+scheduled on the new queue; the only cleanup that a dead current server delays is the deletion
+of its queue, which is retried a bounded number of times and then abandoned.

scripts/main/simplex-servers-update

@@ -237,11 +237,11 @@ checks() {
     exit 1
   fi
 
+  mkdir -p "$path_conf_info" "$path_tmp_bin"
+
   check_versions
   check_distro
 
-  mkdir -p $path_conf_info $path_tmp_bin
-
   return 0
 }
 

scripts/resolver/.env

@@ -0,0 +1,22 @@
+# ============================================================================
+# Required settings — the stack will not start without these.
+# ============================================================================
+
+# Ethereum network: mainnet (the SNRC `.testing` contracts live on mainnet)
+# or holesky (test). Mainnet full sync needs ~1 day and ~1.2 TB NVMe.
+NETWORK=mainnet
+
+# Beacon checkpoint-sync URL — used ONCE on first sync. Must expose the heavy
+# /eth/v2/debug/beacon/states/finalized endpoint (generic beacon APIs do not;
+# use a dedicated checkpoint provider). List: https://eth-clients.github.io/checkpoint-sync-endpoints/
+#   mainnet: https://mainnet-checkpoint-sync.attestant.io  (also beaconstate.info, sync-mainnet.beaconcha.in)
+#   holesky: https://checkpoint-sync.holesky.ethpandaops.io
+TRUSTED_NODE_URL=https://mainnet-checkpoint-sync.attestant.io
+
+# ============================================================================
+# Optional overrides — sensible defaults are baked into docker-compose.yml,
+# so leave these commented unless you need to change them.
+# ============================================================================
+
+# Nimbus NAT (default: any). For a stable public node set an explicit IP:
+#   NAT=extip:1.2.3.4        # your public IPv4: curl -s ifconfig.me

scripts/resolver/README.md

@@ -0,0 +1,146 @@
+# Self-hosted SNRC stack
+
+One `docker compose up` runs the self-hosted SimpleX Namespace (SNRC) backend
+against **Ethereum mainnet** (where the `.testing` contracts live):
+
+| # | Component | What it does |
+|---|---|---|
+| 1 | **reth + nimbus** | self-hosted Ethereum node (`--minimal` — enough for the resolver's `eth_call` at chain head) |
+| 2 | **resolver** | the REST resolver the smp-server's `[NAMES]` role queries (`snrc-resolve.py`) |
+
+## Requirements
+
+- **Docker** + Compose v2.
+- **≥ 300 GB NVMe SSD** for `reth --minimal` (~260 GB on mainnet; TLC, not QLC
+  — QLC stalls during sync) + **32 GB RAM**, fast multi-core CPU.
+- **~1 day** for the initial reth sync. The resolver returns errors until reth
+  has caught up — that's expected.
+- Firewall: open p2p ports `30303` (tcp/udp) and `9000` (tcp/udp).
+
+## 1. Configure
+
+Edit `.env` — the defaults work as-is; override only if needed:
+
+```sh
+NETWORK=mainnet                                               # default
+TRUSTED_NODE_URL=https://mainnet-checkpoint-sync.attestant.io # default
+```
+
+Everything else (NAT) has a working default baked into `docker-compose.yml`;
+uncomment the hints in `.env` only to override.
+
+## 2. Run
+
+```sh
+cd scripts/resolver
+docker compose up -d
+docker compose logs -f reth resolver
+```
+
+`depends_on` handles ordering automatically (start node → start resolver).
+
+## 3. Wait for the node to sync
+
+```sh
+docker compose logs --tail=20 reth
+```
+
+This is the long pole (~1 day on mainnet). Until reth is synced the resolver
+returns `502`.
+
+## Verify
+
+Run these once the stack is up (the node-dependent ones pass after sync):
+
+**1. reth is reachable and reporting a block:**
+```sh
+curl -s -X POST http://127.0.0.1:8545 \
+  -H 'content-type: application/json' \
+  -d '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}' | jq
+```
+
+**2. resolver is healthy:**
+```sh
+curl -s http://127.0.0.1:8000/health | jq
+# → {"ok": true, "rpc": "http://reth:8545", "registries": {"testing": "0x…", "simplex": ""}}
+```
+
+**3. resolver resolves a live name** (`foobar.testing` is a populated test name):
+```sh
+curl -s http://127.0.0.1:8000/resolve/foobar.testing | jq
+# → {"name":"foobar.testing","nickname":"Foo","simplexContact":["https://smp16.simplex.im/a#…"], … }
+```
+
+**Wire your smp-server:** in its `[NAMES]` section set
+`resolver_endpoint: http://127.0.0.1:8000` (no auth needed for loopback).
+
+## Ports (all loopback unless noted)
+
+| Service | Host | Purpose |
+|---|---|---|
+| reth JSON-RPC | `127.0.0.1:8545` | smp-server RPC |
+| reth p2p | `:30303` tcp/udp | Ethereum sync (open on firewall) |
+| nimbus p2p | `:9000` tcp/udp | beacon sync (open on firewall) |
+| nimbus REST | `127.0.0.1:5052` | beacon API |
+| **resolver** | `127.0.0.1:8000` | SNRC REST (`/resolve`, `/health`) |
+
+## Caveats
+
+- **All images track `:latest`** (reth, nimbus) — you get upstream fixes on each
+  `docker compose pull`; re-run the verify checks after pulling.
+- All ports bind to loopback; expose only what you put behind a TLS reverse proxy.
+
+## Teardown
+
+```sh
+docker compose down       # stop, keep all state
+docker compose down -v    # also wipe volumes → full re-sync
+```
+
+`down -v` wipes the chain data (full re-sync on the next `up`).
+
+---
+
+## Resolver API reference
+
+The resolver (`snrc-resolve.py`, host `127.0.0.1:8000`) is also runnable
+standalone for local dev (no Docker), via [`uv`](https://docs.astral.sh/uv/):
+
+```sh
+uv run scripts/resolver/service/snrc-resolve.py  # defaults to local reth + mainnet .testing
+```
+
+### Response shape
+
+```jsonc
+{
+  "name": "foobar.testing",
+  "nickname": "Foo", "website": "https://foo.bar", "location": "",
+  "simplexContact": ["https://smp16.simplex.im/a#…", "https://smp11…"],  // primary first, fallbacks after
+  "simplexChannel": [],
+  "eth": null, "btc": "bc1q…", "xmr": "4ANz…", "dot": "139G…",
+  "owner": "0xd83b…", "resolver": "0x80fa…"
+}
+```
+
+`simplexContact`/`simplexChannel` are arrays (a name can advertise multiple SMP
+servers; clients try them in order). On-chain they're a single comma-separated
+text record; the resolver splits/trims/drops-empties. Address encodings are
+canonical per chain (EIP-55 / bech32 / SS58 / Monero-base58). Subnames work
+identically (`bar.foobar.testing`).
+
+### Status codes
+
+| Status | Meaning |
+|---|---|
+| 200 | resolved |
+| 400 | TLD not configured, or not a fully-qualified name |
+| 404 | name has no resolver set on the registry |
+| 502 | upstream RPC error / reth not synced |
+
+### Configuring registries
+
+Defaults to mainnet `.testing` (`0x03f438…`); `.simplex` is unset until
+deployed. Override per TLD via env on the `resolver` service in
+`docker-compose.yml` (`SNRC_REGISTRY_TESTING` / `SNRC_REGISTRY_SIMPLEX`), or as
+env vars for the standalone script.

scripts/resolver/docker-compose.yml

@@ -0,0 +1,160 @@
+services:
+  # One-shot setup (runs as root): generates /jwt/jwt.hex and chowns the
+  # nimbus-data volume to UID 1000 (the user Nimbus runs as inside its image).
+  # Without this chown Nimbus gets "Permission denied" on its data dir
+  # because docker creates fresh named volumes owned by root.
+  init:
+    image: alpine:latest
+    volumes:
+      - jwt:/jwt
+      - nimbus-data:/nimbus-data
+    command: >
+      sh -c '
+        set -e;
+        if [ ! -f /jwt/jwt.hex ]; then
+          apk add --no-cache openssl >/dev/null;
+          openssl rand -hex 32 | tr -d "\n" > /jwt/jwt.hex;
+          chmod 644 /jwt/jwt.hex;
+          echo "Generated /jwt/jwt.hex";
+        else
+          echo "jwt.hex already exists";
+        fi;
+        chown 1000:1000 /nimbus-data;
+        echo "Chowned /nimbus-data to 1000:1000";
+      '
+    restart: "no"
+
+  # One-shot: fetches a recent finalised checkpoint into the Nimbus data dir
+  # using the trustedNodeSync subcommand. Skipped if the data dir is already
+  # initialised, so subsequent compose-ups are no-ops.
+  nimbus-checkpoint-sync:
+    image: statusim/nimbus-eth2:multiarch-latest
+    depends_on:
+      init:
+        condition: service_completed_successfully
+    volumes:
+      - nimbus-data:/home/user/nimbus-eth2/build/data
+    entrypoint:
+      - sh
+      - -c
+      - |
+        if [ -d /home/user/nimbus-eth2/build/data/${NETWORK}/db ]; then
+          echo "Nimbus data dir already initialised — skipping checkpoint sync";
+          exit 0;
+        fi;
+        /home/user/nimbus-eth2/build/nimbus_beacon_node trustedNodeSync \
+          --network=${NETWORK} \
+          --data-dir=/home/user/nimbus-eth2/build/data/${NETWORK} \
+          --trusted-node-url=${TRUSTED_NODE_URL} \
+          --backfill=false
+    restart: "no"
+
+  # One-shot: downloads a pre-synced snapshot from snapshots.reth.rs into the
+  # Reth data dir. Turns a multi-day from-scratch sync into a ~hour download.
+  # Skipped if the data dir is already initialised — re-runs are no-ops.
+  # Privacy note: snapshots.reth.rs sees this download (operator existence).
+  # Subsequent eth_call traffic stays local.
+  reth-snapshot-init:
+    image: ghcr.io/paradigmxyz/reth:latest
+    depends_on:
+      init:
+        condition: service_completed_successfully
+    volumes:
+      - reth-data:/data
+    entrypoint:
+      - sh
+      - -c
+      - |
+        if [ -f /data/.snapshot-done ] || [ -d /data/db ]; then
+          echo "Reth data already initialised — skipping snapshot download";
+          exit 0;
+        fi;
+        echo "Downloading Reth ${NETWORK} --minimal snapshot...";
+        reth download --datadir /data --chain ${NETWORK} --minimal && \
+        touch /data/.snapshot-done && \
+        echo "Snapshot download complete"
+    restart: "no"
+
+  reth:
+    image: ghcr.io/paradigmxyz/reth:latest
+    depends_on:
+      reth-snapshot-init:
+        condition: service_completed_successfully
+    volumes:
+      - reth-data:/data
+      - jwt:/jwt:ro
+    ports:
+      # JSON-RPC for smp-server. Bound to loopback — put Caddy in front for remote access.
+      - "127.0.0.1:8545:8545"
+      # p2p (Ethereum network). Open these on your firewall for sync.
+      - "30303:30303/tcp"
+      - "30303:30303/udp"
+    command: >
+      node
+      --datadir /data
+      --chain ${NETWORK}
+      --minimal
+      --authrpc.jwtsecret /jwt/jwt.hex
+      --authrpc.addr 0.0.0.0 --authrpc.port 8551
+      --http
+      --http.addr 0.0.0.0 --http.port 8545
+      --http.api eth,net
+      --rpc.gascap 50000000
+      --port 30303
+      --discovery.port 30303
+    restart: unless-stopped
+
+  nimbus:
+    image: statusim/nimbus-eth2:multiarch-latest
+    depends_on:
+      nimbus-checkpoint-sync:
+        condition: service_completed_successfully
+    volumes:
+      - nimbus-data:/home/user/nimbus-eth2/build/data
+      - jwt:/jwt:ro
+    ports:
+      - "9000:9000/tcp"
+      - "9000:9000/udp"
+      - "127.0.0.1:5052:5052"
+    command: >
+      --network=${NETWORK}
+      --data-dir=/home/user/nimbus-eth2/build/data/${NETWORK}
+      --el=http://reth:8551
+      --jwt-secret=/jwt/jwt.hex
+      --non-interactive
+      --rest --rest-address=0.0.0.0 --rest-port=5052
+      --nat=${NAT:-any}
+    restart: unless-stopped
+
+  # SNRC REST resolver. Talks to reth on the compose-internal network,
+  # exposes /resolve and /health on 127.0.0.1:8000 by default. The
+  # smp-server points its [NAMES] resolver_endpoint at this URL.
+  # To change the host port, edit the LEFT side of the port mapping below.
+  resolver:
+    build:
+      context: ./service
+      dockerfile: Dockerfile
+    depends_on:
+      # reth's `service_started` is sufficient — the resolver tolerates
+      # eth_call failures gracefully (returns 502 with the error body), so
+      # starting before reth has finished snapshot replay just yields a few
+      # 502s until the chain is queryable. The upstream reth image doesn't
+      # ship a HEALTHCHECK, so we can't gate on healthy.
+      reth:
+        condition: service_started
+    environment:
+      SNRC_RPC: http://reth:8545
+      SNRC_BIND: 0.0.0.0
+      # Registry addresses cascade through the script's own defaults
+      # (mainnet `.testing`; `.simplex` unconfigured). Set explicitly here
+      # only if you're deploying against a different network or contract.
+      # SNRC_REGISTRY_TESTING: 0x...
+      # SNRC_REGISTRY_SIMPLEX: 0x...
+    ports:
+      - "127.0.0.1:8000:8000"
+    restart: unless-stopped
+
+volumes:
+  reth-data:
+  nimbus-data:
+  jwt:

scripts/resolver/service/Dockerfile

@@ -0,0 +1,48 @@
+# syntax=docker/dockerfile:1.7
+# ---------- builder ----------
+# Use the official uv image (Astral) on top of a slim Python base.
+# uv resolves and installs the lockfile-free pyproject.toml in seconds and
+# produces a portable .venv we can copy into the runtime stage.
+FROM ghcr.io/astral-sh/uv:python3.13-bookworm-slim AS builder
+
+ENV UV_LINK_MODE=copy \
+    UV_COMPILE_BYTECODE=1 \
+    UV_PYTHON_DOWNLOADS=never \
+    UV_NO_PROGRESS=1
+
+WORKDIR /app
+
+# Install deps first (separate layer) — script edits won't bust this cache.
+COPY pyproject.toml ./
+RUN --mount=type=cache,target=/root/.cache/uv \
+    uv sync --no-dev --no-install-project
+
+# Script is added after the dep layer for cache friendliness.
+COPY snrc-resolve.py ./
+
+# ---------- runtime ----------
+# Slim runtime — only the venv + script. No uv, no apt.
+FROM python:3.13-slim AS runtime
+
+ENV PYTHONUNBUFFERED=1 \
+    PYTHONDONTWRITEBYTECODE=1 \
+    PATH="/app/.venv/bin:$PATH"
+
+# Non-root user (matches resolver privacy posture: it has no need for root).
+RUN groupadd --system --gid 10001 snrc && \
+    useradd  --system --uid 10001 --gid snrc --no-create-home --shell /usr/sbin/nologin snrc
+
+WORKDIR /app
+COPY --from=builder --chown=snrc:snrc /app /app
+
+USER snrc:snrc
+
+EXPOSE 8000
+
+# Liveness check hits the script's own /health route. ThreadingHTTPServer is
+# fast enough that 3s is generous for a localhost probe; restart if it stops
+# responding entirely.
+HEALTHCHECK --interval=30s --timeout=5s --start-period=10s --retries=3 \
+    CMD ["python", "-c", "import urllib.request, sys; sys.exit(0 if urllib.request.urlopen('http://127.0.0.1:8000/health', timeout=3).status == 200 else 1)"]
+
+ENTRYPOINT ["python", "snrc-resolve.py"]

scripts/resolver/service/pyproject.toml

@@ -0,0 +1,13 @@
+[project]
+name = "snrc-resolve"
+version = "0.1.0"
+description = "SimpleX Namespace (SNRC) resolver — REST API over ENS-shaped Ethereum registries"
+readme = "README.md"
+requires-python = ">=3.11"
+license = "AGPL-3.0-only"
+dependencies = [
+  "eth-hash[pycryptodome]>=0.7",
+]
+
+[tool.uv]
+package = false

scripts/resolver/service/snrc-resolve.py

@@ -0,0 +1,517 @@
+#!/usr/bin/env python3
+# /// script
+# requires-python = ">=3.11"
+# dependencies = [
+#   "eth-hash[pycryptodome]>=0.7",
+# ]
+# ///
+"""SimpleX Namespace (SNRC) resolver — REST API.
+
+Resolves names like `alice.testing` / `bob.simplex` against the SNRC
+deployment on Ethereum mainnet (or any compatible ENS-shaped registry)
+and returns a flat JSON document with these fields:
+
+  name, nickname, website, location,
+  simplexContact, simplexChannel,    -- list[str], primary first
+  eth, btc, xmr, dot,
+  owner, resolver
+
+`simplexContact` and `simplexChannel` are arrays so a name can advertise
+multiple SMP servers for redundancy. Clients SHOULD try the URLs in the
+order returned. The on-chain text record stores them as a single
+`LINK_SEPARATOR` (`;`)-joined string; this resolver splits and trims into a list.
+
+All keys are valid Haskell record-field identifiers (lowercase initial,
+no dots), so consumers can derive aeson FromJSON instances directly
+without a key-rewriting layer.
+
+Usage:
+  ./snrc-resolve.py                    # serve on :8000
+
+  curl -s http://127.0.0.1:8000/resolve/foobar.testing | jq .
+  curl -s http://127.0.0.1:8000/health
+
+Environment:
+  SNRC_RPC               JSON-RPC endpoint (default: http://127.0.0.1:8545)
+  SNRC_REGISTRY_TESTING  ENSRegistry for the .testing deployment
+                         (default: mainnet,
+                          0x58fc46996d975c57883564648bda5206d1a0102b)
+  SNRC_REGISTRY_SIMPLEX  ENSRegistry for the .simplex deployment
+                         (default: empty — TLD not yet deployed)
+  SNRC_PORT              Listen port (default: 8000)
+  SNRC_BIND              Bind address (default: 0.0.0.0)
+
+Each TLD is a separate SNRC deployment with its own ENSRegistry; the
+resolver dispatches by the queried name's rightmost label.
+
+Dependencies are declared inline (PEP 723) at the top of this file. Run with:
+  uv run snrc-resolve.py          # uv resolves & caches deps; one-line setup
+  python snrc-resolve.py          # if eth-hash[pycryptodome] is already installed
+
+Addresses are returned in each chain's canonical presentation:
+  eth  EIP-55 mixed-case checksummed hex      (e.g. 0xEa65A0…1572)
+  btc  bech32(m) for segwit/taproot, base58check for P2PKH/P2SH
+       (e.g. bc1q…  /  1A1zP1…)
+  dot  SS58 with Polkadot network prefix 0    (e.g. 15oF4u…)
+  xmr  Monero base58                          (e.g. 4Aux5y…)
+Unrecognised payloads fall back to `0x`-prefixed raw hex.
+"""
+
+import hashlib
+import json
+import os
+import sys
+from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
+from urllib.parse import unquote, urlparse
+from urllib.request import Request, urlopen
+
+from eth_hash.auto import keccak
+
+RPC = os.environ.get("SNRC_RPC", "http://127.0.0.1:8545")
+BIND = os.environ.get("SNRC_BIND", "0.0.0.0")
+PORT = int(os.environ.get("SNRC_PORT", "8000"))
+
+# Each TLD is its own SNRC deployment with its own ENSRegistry. Dispatch
+# happens on the rightmost label of the queried name. Empty / unset means
+# "not deployed" — requests for that TLD return 400 with a clear error.
+# `... or "..."` makes the script's defaults the single source of truth:
+# unset AND empty-string both fall through to the literal. docker-compose
+# can therefore pass `SNRC_REGISTRY_TESTING=${SNRC_REGISTRY_TESTING:-}`
+# without duplicating the registry address.
+REGISTRIES = {
+    "testing": os.environ.get("SNRC_REGISTRY_TESTING", "")
+    or "0x58fc46996d975c57883564648bda5206d1a0102b",  # mainnet .testing
+    "simplex": os.environ.get("SNRC_REGISTRY_SIMPLEX", ""),  # not deployed yet
+}
+
+# SLIP-44 coin types (https://github.com/satoshilabs/slips/blob/master/slip-0044.md)
+COIN_ETH = 60
+COIN_BTC = 0
+COIN_XMR = 128
+COIN_DOT = 354
+
+ZERO_ADDR = "0x0000000000000000000000000000000000000000"
+
+
+# ---------- RPC + ABI helpers (mirrors ens-lookup.py shape) ----------
+
+def rpc(method, params):
+    body = json.dumps(
+        {"jsonrpc": "2.0", "method": method, "params": params, "id": 1}
+    ).encode()
+    # Set a non-default User-Agent; Cloudflare-fronted public RPCs (drpc,
+    # publicnode, etc.) reject `Python-urllib/3.x` with 403.
+    req = Request(
+        RPC,
+        data=body,
+        headers={
+            "Content-Type": "application/json",
+            "User-Agent": "snrc-resolve/1.0",
+        },
+    )
+    res = json.loads(urlopen(req, timeout=15).read())
+    if "error" in res:
+        raise RuntimeError(res["error"])
+    return res["result"]
+
+
+def namehash(name: str) -> bytes:
+    node = b"\x00" * 32
+    if name:
+        for label in reversed(name.split(".")):
+            node = keccak(node + keccak(label.encode()))
+    return node
+
+
+def selector(signature: str) -> str:
+    return "0x" + keccak(signature.encode())[:4].hex()
+
+
+def eth_call(to: str, data: str) -> str:
+    return rpc("eth_call", [{"to": to, "data": data}, "latest"])
+
+
+def decode_address(hex_data: str) -> str:
+    return "0x" + hex_data[-40:]
+
+
+def decode_bytes(hex_data: str) -> bytes:
+    raw = bytes.fromhex(hex_data[2:] if hex_data.startswith("0x") else hex_data)
+    if len(raw) < 64:
+        return b""
+    length = int.from_bytes(raw[32:64], "big")
+    return raw[64:64 + length]
+
+
+def encode_text_call(node: bytes, key: str) -> str:
+    sel = selector("text(bytes32,string)")
+    head = node.hex() + (0x40).to_bytes(32, "big").hex()
+    key_bytes = key.encode()
+    body = len(key_bytes).to_bytes(32, "big").hex() + key_bytes.hex()
+    body += "00" * ((-len(key_bytes)) % 32)
+    return sel + head + body
+
+
+def text(resolver: str, node: bytes, key: str) -> str:
+    raw = decode_bytes(eth_call(resolver, encode_text_call(node, key)))
+    return raw.decode("utf-8", errors="replace") if raw else ""
+
+
+def encode_addr_multicoin_call(node: bytes, coin_type: int) -> str:
+    """ENSIP-9 addr(bytes32 node, uint256 coinType) — both static, no offsets."""
+    return (
+        selector("addr(bytes32,uint256)")
+        + node.hex()
+        + coin_type.to_bytes(32, "big").hex()
+    )
+
+
+def addr_multicoin(resolver: str, node: bytes, coin_type: int):
+    """Read ENSIP-9 raw bytes for `coinType`, then encode to that chain's
+    canonical presentation form. Falls back to `0x`-prefixed hex if the
+    payload doesn't match any recognised on-chain shape. Returns None when
+    the record is unset."""
+    try:
+        raw = decode_bytes(eth_call(resolver, encode_addr_multicoin_call(node, coin_type)))
+    except RuntimeError:
+        return None
+    if not raw:
+        return None
+    # An all-zero payload is the ENS convention for "unset" — many tools
+    # write 20 zero bytes for coinType=60 instead of clearing the slot.
+    # Treat it as null so the response doesn't surface a zero address.
+    if raw == b"\x00" * len(raw):
+        return None
+    encoder = COIN_ENCODERS.get(coin_type)
+    if encoder is None:
+        return "0x" + raw.hex()
+    try:
+        return encoder(raw) or ("0x" + raw.hex())
+    except Exception:
+        return "0x" + raw.hex()
+
+
+# ---------- Coin-specific address encoders ----------
+# Each takes raw bytes as stored under ENSIP-9 and returns the canonical
+# user-facing string for that chain (EIP-55 for ETH, bech32/base58check
+# for BTC, SS58 for DOT, Monero-base58 for XMR). All stdlib + eth_hash.
+
+
+B58_ALPHA = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"
+
+
+def _b58_encode(b: bytes) -> str:
+    n = int.from_bytes(b, "big")
+    out = ""
+    while n:
+        n, r = divmod(n, 58)
+        out = B58_ALPHA[r] + out
+    # leading zero bytes → leading '1's
+    pad = len(b) - len(b.lstrip(b"\x00"))
+    return "1" * pad + out
+
+
+def _b58check_encode(payload: bytes) -> str:
+    """Base58Check used by BTC legacy/P2SH: payload + dSHA256(payload)[:4]."""
+    chk = hashlib.sha256(hashlib.sha256(payload).digest()).digest()[:4]
+    return _b58_encode(payload + chk)
+
+
+# ---- Bech32 / Bech32m (BIP-173 / BIP-350) ----
+
+_BECH32_CHARSET = "qpzry9x8gf2tvdw0s3jn54khce6mua7l"
+_BECH32_GEN = [0x3B6A57B2, 0x26508E6D, 0x1EA119FA, 0x3D4233DD, 0x2A1462B3]
+
+
+def _bech32_polymod(values):
+    chk = 1
+    for v in values:
+        b = chk >> 25
+        chk = ((chk & 0x1FFFFFF) << 5) ^ v
+        for i in range(5):
+            if (b >> i) & 1:
+                chk ^= _BECH32_GEN[i]
+    return chk
+
+
+def _bech32_hrp_expand(hrp):
+    return [ord(c) >> 5 for c in hrp] + [0] + [ord(c) & 31 for c in hrp]
+
+
+def _bech32_create_checksum(hrp, data, spec):
+    const = 1 if spec == "bech32" else 0x2BC830A3  # bech32m
+    values = _bech32_hrp_expand(hrp) + data + [0] * 6
+    polymod = _bech32_polymod(values) ^ const
+    return [(polymod >> 5 * (5 - i)) & 31 for i in range(6)]
+
+
+def _bech32_encode(hrp, data, spec):
+    combined = data + _bech32_create_checksum(hrp, data, spec)
+    return hrp + "1" + "".join(_BECH32_CHARSET[d] for d in combined)
+
+
+def _convertbits(data, frombits, tobits, pad=True):
+    acc = 0
+    bits = 0
+    ret = []
+    maxv = (1 << tobits) - 1
+    max_acc = (1 << (frombits + tobits - 1)) - 1
+    for value in data:
+        if value < 0 or (value >> frombits):
+            return None
+        acc = ((acc << frombits) | value) & max_acc
+        bits += frombits
+        while bits >= tobits:
+            bits -= tobits
+            ret.append((acc >> bits) & maxv)
+    if pad and bits:
+        ret.append((acc << (tobits - bits)) & maxv)
+    elif not pad and (bits >= frombits or ((acc << (tobits - bits)) & maxv)):
+        return None
+    return ret
+
+
+def _segwit_encode(hrp: str, witver: int, witprog: bytes) -> str:
+    spec = "bech32" if witver == 0 else "bech32m"
+    data = [witver] + _convertbits(list(witprog), 8, 5)
+    return _bech32_encode(hrp, data, spec)
+
+
+# ---- BTC scriptPubKey → address ----
+# ENSIP-9 stores the raw output script. Dispatch by length + opcode prefix.
+
+def _btc_encode(raw: bytes) -> str | None:
+    hrp = "bc"  # mainnet
+    if len(raw) == 25 and raw[:3] == b"\x76\xa9\x14" and raw[23:25] == b"\x88\xac":
+        return _b58check_encode(b"\x00" + raw[3:23])  # P2PKH
+    if len(raw) == 23 and raw[:2] == b"\xa9\x14" and raw[22:23] == b"\x87":
+        return _b58check_encode(b"\x05" + raw[2:22])  # P2SH
+    if len(raw) == 22 and raw[:2] == b"\x00\x14":
+        return _segwit_encode(hrp, 0, raw[2:22])  # P2WPKH
+    if len(raw) == 34 and raw[:2] == b"\x00\x20":
+        return _segwit_encode(hrp, 0, raw[2:34])  # P2WSH
+    if len(raw) == 34 and raw[:2] == b"\x51\x20":
+        return _segwit_encode(hrp, 1, raw[2:34])  # P2TR
+    return None
+
+
+# ---- Polkadot SS58 ----
+# Per SS58 spec: base58( prefix_byte + pubkey + blake2b-512("SS58PRE" + body)[:2] )
+# Polkadot mainnet uses network prefix 0 (single byte); Kusama uses 2.
+
+_SS58_PRE = b"SS58PRE"
+
+
+def _ss58_encode(pubkey: bytes, network_prefix: int = 0) -> str:
+    if len(pubkey) != 32:
+        return None
+    body = bytes([network_prefix]) + pubkey
+    checksum = hashlib.blake2b(_SS58_PRE + body, digest_size=64).digest()[:2]
+    return _b58_encode(body + checksum)
+
+
+def _dot_encode(raw: bytes) -> str | None:
+    return _ss58_encode(raw, network_prefix=0)
+
+
+# ---- Monero base58 ----
+# Monero base58 encodes in 8-byte blocks; each full block → 11 chars, partial
+# block sizes per fixed table. Alphabet is identical to Bitcoin's.
+
+_XMR_BLOCK_SIZES = [0, 2, 3, 5, 6, 7, 9, 10, 11]
+
+
+def _xmr_encode(raw: bytes) -> str:
+    out = []
+    for i in range(0, len(raw), 8):
+        chunk = raw[i:i + 8]
+        n = int.from_bytes(chunk, "big")
+        width = 11 if len(chunk) == 8 else _XMR_BLOCK_SIZES[len(chunk)]
+        block = []
+        for _ in range(width):
+            n, r = divmod(n, 58)
+            block.append(B58_ALPHA[r])
+        out.append("".join(reversed(block)))
+    return "".join(out)
+
+
+# ---- ETH EIP-55 mixed-case checksum ----
+
+def _eth_encode(raw: bytes) -> str | None:
+    if len(raw) != 20:
+        return None
+    hex_addr = raw.hex()
+    hash_hex = keccak(hex_addr.encode()).hex()
+    return "0x" + "".join(
+        c.upper() if c.isalpha() and int(hash_hex[i], 16) >= 8 else c
+        for i, c in enumerate(hex_addr)
+    )
+
+
+COIN_ENCODERS = {
+    COIN_ETH: _eth_encode,
+    COIN_BTC: _btc_encode,
+    COIN_XMR: _xmr_encode,
+    COIN_DOT: _dot_encode,
+}
+
+
+# ---------- Resolution logic ----------
+
+# Text-record keys we read from the resolver. Surfaced under the response
+# field names listed in the docstring above. `name` and `description` are
+# common ENS fallbacks for a human-readable nickname.
+TEXT_KEYS = [
+    "name",
+    "nickname",
+    "description",
+    "url",
+    "location",
+    "simplex.contact",
+    "simplex.channel",
+]
+
+
+# Separator that joins the SMP-server URL list inside a simplex.contact /
+# simplex.channel text record. MUST match SIMPLEX_LINK_SEPARATOR in the dApp
+# (ens-app-v3 src/constants/simplex.ts) — the two sides decode the same record.
+LINK_SEPARATOR = ";"
+
+
+def split_links(value: str) -> list:
+    """Split a separator-joined text record into an ordered list of entries.
+
+    Trims whitespace around each element and drops empties so trailing
+    separators, doubled separators, and all-whitespace inputs all yield clean
+    output. Single-value records yield a 1-element list; empty inputs
+    yield `[]`. Used for `simplex.contact` / `simplex.channel`, which
+    store one-or-more SMP-server URLs as a single `LINK_SEPARATOR`-joined string.
+    """
+    return [item.strip() for item in value.split(LINK_SEPARATOR) if item.strip()]
+
+
+def resolve(name: str):
+    tld = name.rsplit(".", 1)[-1]
+    registry = REGISTRIES.get(tld)
+    if not registry:
+        configured = [k for k, v in REGISTRIES.items() if v]
+        return 400, {
+            "name": name,
+            "error": f"TLD '{tld}' is not configured on this resolver",
+            "configured_tlds": configured,
+        }
+
+    node = namehash(name)
+    node_hex = node.hex()
+
+    resolver_raw = eth_call(registry, selector("resolver(bytes32)") + node_hex)
+    resolver_addr = decode_address(resolver_raw)
+    if resolver_addr == ZERO_ADDR:
+        return 404, {"name": name, "error": "no resolver set for this name"}
+
+    owner_raw = eth_call(registry, selector("owner(bytes32)") + node_hex)
+    owner = decode_address(owner_raw)
+
+    texts = {}
+    for k in TEXT_KEYS:
+        try:
+            v = text(resolver_addr, node, k)
+        except RuntimeError:
+            v = ""
+        if v:
+            texts[k] = v
+
+    # The user-facing "nickname" prefers an explicit `nickname` record,
+    # falls back to `name`, then `description` (ENSIP-5 convention).
+    nickname = texts.get("nickname") or texts.get("name") or texts.get("description") or ""
+
+    # Keys chosen to be valid Haskell record-field identifiers (lowercase
+    # initial, no dots) so consumers can derive aeson FromJSON instances
+    # without a key-rewriting layer. On-chain text-record names still
+    # use the ENSIP-5 dot convention (e.g. "simplex.contact") — only the
+    # resolver's JSON surface camelCases them.
+    return 200, {
+        "name": name,
+        "nickname": nickname,
+        "website": texts.get("url", ""),
+        "location": texts.get("location", ""),
+        "simplexContact": split_links(texts.get("simplex.contact", "")),
+        "simplexChannel": split_links(texts.get("simplex.channel", "")),
+        "eth": addr_multicoin(resolver_addr, node, COIN_ETH),
+        "btc": addr_multicoin(resolver_addr, node, COIN_BTC),
+        "xmr": addr_multicoin(resolver_addr, node, COIN_XMR),
+        "dot": addr_multicoin(resolver_addr, node, COIN_DOT),
+        "owner": owner,
+        "resolver": resolver_addr,
+    }
+
+
+# ---------- HTTP layer ----------
+
+class Handler(BaseHTTPRequestHandler):
+    def do_GET(self):  # noqa: N802 - http.server contract
+        path = urlparse(self.path).path
+        parts = [unquote(p) for p in path.split("/") if p]
+
+        if parts == ["health"]:
+            self._respond(
+                200,
+                {"ok": True, "rpc": RPC, "registries": REGISTRIES},
+            )
+            return
+
+        if len(parts) == 2 and parts[0] == "resolve":
+            name = parts[1].strip().lower()
+            if not name or "." not in name:
+                self._respond(
+                    400,
+                    {
+                        "error": "expected fully-qualified name, e.g. /resolve/alice.testing",
+                        "got": name,
+                    },
+                )
+                return
+            try:
+                status, body = resolve(name)
+            except Exception as e:  # surface upstream errors as 502
+                status, body = 502, {"name": name, "error": f"{type(e).__name__}: {e}"}
+            self._respond(status, body)
+            return
+
+        self._respond(
+            404,
+            {"error": "not found", "routes": ["/health", "/resolve/<name>"]},
+        )
+
+    def _respond(self, status: int, body: dict):
+        data = json.dumps(body, indent=2).encode()
+        self.send_response(status)
+        self.send_header("Content-Type", "application/json")
+        self.send_header("Content-Length", str(len(data)))
+        self.end_headers()
+        self.wfile.write(data)
+
+    def log_message(self, fmt, *args):
+        # Quiet the default per-request access log; route to stderr in one line.
+        sys.stderr.write(f"{self.address_string()} - {fmt % args}\n")
+
+
+def main():
+    server = ThreadingHTTPServer((BIND, PORT), Handler)
+    sys.stderr.write(
+        f"snrc-resolve listening on {BIND}:{PORT}\n"
+        f"  RPC = {RPC}\n"
+        f"  Registries:\n"
+    )
+    for tld, addr in REGISTRIES.items():
+        sys.stderr.write(f"    .{tld:<8s} = {addr or '(not configured)'}\n")
+    sys.stderr.write("  GET /resolve/<name>   GET /health\n")
+    try:
+        server.serve_forever()
+    except KeyboardInterrupt:
+        sys.stderr.write("\nshutting down\n")
+        server.server_close()
+
+
+if __name__ == "__main__":
+    main()

scripts/resolver/service/test_snrc_resolve.py

@@ -0,0 +1,86 @@
+#!/usr/bin/env python3
+"""Unit tests for snrc-resolve helpers.
+
+Run with `python3 -m unittest scripts/resolver/service/test_snrc_resolve.py`.
+"""
+
+import importlib.util
+import os
+import unittest
+
+# snrc-resolve.py has a hyphen, so import it via importlib instead of `import`.
+_HERE = os.path.dirname(os.path.abspath(__file__))
+_SPEC = importlib.util.spec_from_file_location(
+    "snrc_resolve", os.path.join(_HERE, "snrc-resolve.py")
+)
+snrc = importlib.util.module_from_spec(_SPEC)
+_SPEC.loader.exec_module(snrc)
+
+
+class SplitLinksTests(unittest.TestCase):
+    """`split_links` decodes the multi-URL convention for simplex.contact /
+    simplex.channel text records. Reuses the same rule the dApp's
+    `parseSimplexUrls` uses (separator `;`), so the two sides round-trip
+    cleanly."""
+
+    def test_empty_string_yields_empty_list(self):
+        self.assertEqual(snrc.split_links(""), [])
+
+    def test_whitespace_only_yields_empty_list(self):
+        self.assertEqual(snrc.split_links("   "), [])
+        self.assertEqual(snrc.split_links(" ; ; "), [])
+
+    def test_single_url_yields_singleton_list(self):
+        self.assertEqual(
+            snrc.split_links("https://smp16.simplex.im/a#H1"),
+            ["https://smp16.simplex.im/a#H1"],
+        )
+
+    def test_two_urls_split_on_separator(self):
+        self.assertEqual(
+            snrc.split_links(
+                "https://smp16.simplex.im/a#H1;https://smp19.simplex.im/a#H1"
+            ),
+            [
+                "https://smp16.simplex.im/a#H1",
+                "https://smp19.simplex.im/a#H1",
+            ],
+        )
+
+    def test_whitespace_around_separators_is_trimmed(self):
+        self.assertEqual(
+            snrc.split_links(
+                "  https://smp16.simplex.im/a#H1 ;\thttps://smp19.simplex.im/a#H1 "
+            ),
+            [
+                "https://smp16.simplex.im/a#H1",
+                "https://smp19.simplex.im/a#H1",
+            ],
+        )
+
+    def test_trailing_separator_does_not_produce_empty_entry(self):
+        self.assertEqual(
+            snrc.split_links("https://smp16.simplex.im/a#H1;"),
+            ["https://smp16.simplex.im/a#H1"],
+        )
+
+    def test_doubled_separator_does_not_produce_empty_entry(self):
+        self.assertEqual(
+            snrc.split_links(
+                "https://smp16.simplex.im/a#H1;;https://smp19.simplex.im/a#H1"
+            ),
+            [
+                "https://smp16.simplex.im/a#H1",
+                "https://smp19.simplex.im/a#H1",
+            ],
+        )
+
+    def test_order_is_preserved(self):
+        self.assertEqual(
+            snrc.split_links("c;a;b"),
+            ["c", "a", "b"],
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()

scripts/resolver/tools/ens-lookup.py

@@ -0,0 +1,168 @@
+#!/usr/bin/env python3
+"""Resolve an ENS name via local Reth (the same shape SNRC will use).
+
+Usage:
+  ./ens-lookup.py                     # defaults to simplexchat.eth
+  ./ens-lookup.py vitalik.eth
+  ./ens-lookup.py corevo.eth
+
+Requires:  pip install --break-system-packages 'eth-hash[pycryptodome]'
+"""
+
+import base64
+import json
+import sys
+from urllib.request import Request, urlopen
+
+from eth_hash.auto import keccak
+
+RPC = "http://127.0.0.1:8545"
+# ENS Registry (current, post-2020 migration)
+ENS_REGISTRY = "0x00000000000C2E074eC69A0dFb2997BA6C7d2e1e"
+
+
+def rpc(method, params):
+    body = json.dumps({"jsonrpc": "2.0", "method": method, "params": params, "id": 1}).encode()
+    req = Request(RPC, data=body, headers={"Content-Type": "application/json"})
+    res = json.loads(urlopen(req, timeout=15).read())
+    if "error" in res:
+        raise RuntimeError(res["error"])
+    return res["result"]
+
+
+def namehash(name: str) -> bytes:
+    """ENS namehash — recursive keccak256 over reversed labels."""
+    node = b"\x00" * 32
+    if name:
+        for label in reversed(name.split(".")):
+            node = keccak(node + keccak(label.encode()))
+    return node
+
+
+def selector(signature: str) -> str:
+    return "0x" + keccak(signature.encode())[:4].hex()
+
+
+def eth_call(to: str, data: str) -> str:
+    return rpc("eth_call", [{"to": to, "data": data}, "latest"])
+
+
+def decode_address(hex_data: str) -> str:
+    return "0x" + hex_data[-40:]
+
+
+def decode_bytes(hex_data: str) -> bytes:
+    raw = bytes.fromhex(hex_data[2:] if hex_data.startswith("0x") else hex_data)
+    if len(raw) < 64:
+        return b""
+    length = int.from_bytes(raw[32:64], "big")
+    return raw[64:64 + length]
+
+
+def encode_text_call(node: bytes, key: str) -> str:
+    """ABI-encode text(bytes32 node, string key). String arg is dynamic:
+    offset (=0x40) + length + right-padded data."""
+    sel = selector("text(bytes32,string)")
+    head = node.hex() + (0x40).to_bytes(32, "big").hex()
+    key_bytes = key.encode()
+    body = len(key_bytes).to_bytes(32, "big").hex() + key_bytes.hex()
+    # right-pad to 32-byte boundary
+    pad = (-len(key_bytes)) % 32
+    body += "00" * pad
+    return sel + head + body
+
+
+def text(resolver: str, node: bytes, key: str) -> str:
+    raw = decode_bytes(eth_call(resolver, encode_text_call(node, key)))
+    return raw.decode("utf-8", errors="replace") if raw else ""
+
+
+# Common ENS text keys (ENSIP-5). Resolvers may return empty for any of these.
+TEXT_KEYS = [
+    "url",
+    "avatar",
+    "description",
+    "email",
+    "notice",
+    "keywords",
+    "com.twitter",
+    "com.github",
+    "com.discord",
+    "org.telegram",
+    "io.keybase",
+    "xyz.farcaster",
+]
+
+
+def decode_contenthash(raw: bytes) -> str:
+    """ENS contenthash → human-readable URI (best-effort)."""
+    if not raw:
+        return "(empty)"
+    # Multicodec prefixes:
+    #   0xe301 = ipfs-ns + dag-pb (CIDv0/v1)
+    #   0xe501 = ipns-ns
+    #   0xe40101701b... = swarm
+    if raw[:2] == b"\xe3\x01":
+        cid_bytes = raw[2:]
+        # Base32 lowercase + 'b' prefix per CIDv1 spec
+        b32 = base64.b32encode(cid_bytes).decode().lower().rstrip("=")
+        return f"ipfs://b{b32}"
+    if raw[:2] == b"\xe5\x01":
+        cid_bytes = raw[2:]
+        b32 = base64.b32encode(cid_bytes).decode().lower().rstrip("=")
+        return f"ipns://b{b32}"
+    return "0x" + raw.hex()
+
+
+def main():
+    name = sys.argv[1] if len(sys.argv) > 1 else "simplexchat.eth"
+
+    print(f"  name:       {name}")
+    node = namehash(name)
+    print(f"  namehash:   0x{node.hex()}")
+
+    # 1. Ask the registry which resolver is responsible for this name
+    resolver_data = selector("resolver(bytes32)") + node.hex()
+    resolver_raw = eth_call(ENS_REGISTRY, resolver_data)
+    resolver = decode_address(resolver_raw)
+    print(f"  resolver:   {resolver}")
+    if resolver == "0x0000000000000000000000000000000000000000":
+        print("  → no resolver set for this name")
+        return
+
+    node_hex = node.hex()
+
+    # 2. Ask the resolver for the address
+    try:
+        addr = decode_address(eth_call(resolver, selector("addr(bytes32)") + node_hex))
+        print(f"  address:    {addr}")
+    except Exception as e:
+        print(f"  address:    (error: {e})")
+
+    # 3. Ask the resolver for the content hash (IPFS pointer)
+    try:
+        ch = decode_bytes(eth_call(resolver, selector("contenthash(bytes32)") + node_hex))
+        print(f"  contenthash: {decode_contenthash(ch)}")
+    except Exception as e:
+        print(f"  contenthash: (not supported: {e})")
+
+    # 4. Owner from the registry
+    try:
+        owner = decode_address(eth_call(ENS_REGISTRY, selector("owner(bytes32)") + node_hex))
+        print(f"  owner:      {owner}")
+    except Exception as e:
+        print(f"  owner:      (error: {e})")
+
+    # 5. Text records (EIP-634). Print only the non-empty ones.
+    print("  text records:")
+    for key in TEXT_KEYS:
+        try:
+            v = text(resolver, node, key)
+            if v:
+                print(f"    {key:<16s} {v}")
+        except Exception as e:
+            print(f"    {key:<16s} (error: {e})")
+
+
+if __name__ == "__main__":
+    main()

scripts/resolver/tools/progress.py

@@ -0,0 +1,246 @@
+#!/usr/bin/env python3
+"""Sync progress for the Reth + Nimbus stack.
+
+Usage:
+  ./progress.py           # continuous (Ctrl-C to exit, auto-exits when synced)
+  ./progress.py --once    # single snapshot
+
+Requires Nimbus REST port exposed at 127.0.0.1:5052 (add --rest flag in compose).
+"""
+
+import json
+import sys
+import time
+from collections import deque
+from datetime import timedelta
+from urllib.error import URLError
+from urllib.request import Request, urlopen
+
+RETH = "http://127.0.0.1:8545"
+NIMBUS = "http://127.0.0.1:5052"
+INTERVAL = 5
+WINDOW = 60
+BAR_W = 40
+
+# ANSI helpers
+def c(s, code): return f"\033[{code}m{s}\033[0m"
+GREEN, YELLOW, RED, DIM, BOLD = "32", "33", "31", "2;37", "1"
+
+
+def rpc(method):
+    body = json.dumps({"jsonrpc": "2.0", "method": method, "params": [], "id": 1}).encode()
+    req = Request(RETH, data=body, headers={"Content-Type": "application/json"})
+    return json.loads(urlopen(req, timeout=5).read())["result"]
+
+
+def get_reth():
+    try:
+        r = rpc("eth_syncing")
+        try:
+            peers = int(rpc("net_peerCount"), 16)
+        except Exception:
+            peers = -1            # net namespace not exposed
+        if r is False:
+            head = int(rpc("eth_blockNumber"), 16)
+            return {"state": "synced", "current": head, "target": head, "peers": peers,
+                    "stage": None, "stages": {}, "err": None}
+        current = int(r["currentBlock"], 16)
+        highest = int(r["highestBlock"], 16)
+        # Build stage map (name -> block).
+        stages = {s["name"]: int(s["block"], 16) for s in r.get("stages", [])}
+        active_stages = {k: v for k, v in stages.items() if v > 0}
+        # Headers download phase: nothing has progressed yet.
+        if current == 0 and highest == 0 and not active_stages:
+            return {"state": "headers", "current": 0, "target": 0, "peers": peers,
+                    "stage": "Headers", "stages": stages, "err": None}
+        # Derive progress from the stages pipeline.
+        # Bottleneck (rate-limiting stage) = stage with lowest non-zero block.
+        # Target = leading stage block (typically Headers = chain tip).
+        # Reth's top-level currentBlock/highestBlock are unreliable during initial
+        # sync (often 0 until execution stage runs), so prefer stages-derived values.
+        if active_stages:
+            bottleneck = min(active_stages, key=active_stages.get)
+            stage_current = active_stages[bottleneck]
+            stage_target = max(stages.values()) if stages else 0
+            # Trust the stages-derived values if highest is unset or stages tip is higher.
+            if highest <= 0 or stage_target > highest:
+                current = stage_current
+                highest = stage_target
+            elif current <= 0:
+                current = stage_current
+        else:
+            bottleneck = None
+        return {"state": "syncing", "current": current, "target": highest,
+                "peers": peers, "stage": bottleneck, "stages": stages, "err": None}
+    except URLError as e:
+        return {"state": "down", "current": 0, "target": 0, "peers": 0,
+                "stage": None, "stages": {}, "err": str(e.reason)}
+    except Exception as e:
+        return {"state": "error", "current": 0, "target": 0, "peers": 0,
+                "stage": None, "stages": {}, "err": str(e)}
+
+
+def get_nimbus():
+    try:
+        d = json.loads(urlopen(f"{NIMBUS}/eth/v1/node/syncing", timeout=5).read())["data"]
+        peers_d = json.loads(urlopen(f"{NIMBUS}/eth/v1/node/peer_count", timeout=5).read())["data"]
+        head = int(d["head_slot"])
+        dist = int(d["sync_distance"])
+        peers = int(peers_d.get("connected", "0"))
+        return {"state": "synced" if not d["is_syncing"] else "syncing",
+                "current": head, "target": head + dist, "peers": peers,
+                "optimistic": bool(d.get("is_optimistic", False)),
+                "el_offline": bool(d.get("el_offline", False)),
+                "err": None}
+    except URLError as e:
+        return {"state": "down", "current": 0, "target": 0, "peers": 0,
+                "optimistic": False, "el_offline": False, "err": str(e.reason)}
+    except Exception as e:
+        return {"state": "error", "current": 0, "target": 0, "peers": 0,
+                "optimistic": False, "el_offline": False, "err": str(e)}
+
+
+def format_num(n): return f"{n:,}"
+
+
+def format_eta(seconds):
+    if seconds is None: return "?"
+    if seconds < 0: return "?"
+    if seconds < 60: return f"{int(seconds)}s"
+    if seconds < 3600:
+        return f"{int(seconds // 60)}m {int(seconds % 60)}s"
+    if seconds < 86400:
+        return f"{int(seconds // 3600)}h {int((seconds % 3600) // 60)}m"
+    return f"{int(seconds // 86400)}d {int((seconds % 86400) // 3600)}h"
+
+
+def rate_per_sec(history):
+    if len(history) < 2: return None
+    t0, c0 = history[0]
+    t1, c1 = history[-1]
+    if t1 <= t0: return None
+    return (c1 - c0) / (t1 - t0)
+
+
+def eta_seconds(history, target):
+    r = rate_per_sec(history)
+    if r is None or r <= 0: return None
+    remaining = target - history[-1][1]
+    if remaining <= 0: return 0
+    return remaining / r
+
+
+def progress_bar(pct):
+    pct = max(0.0, min(100.0, pct))
+    filled = int(pct / 100 * BAR_W)
+    return c("█" * filled, GREEN) + c("░" * (BAR_W - filled), DIM)
+
+
+def peers_label(peers):
+    if peers < 0:
+        return c("· peers unknown (enable net namespace)", DIM)
+    return c(f"· {peers} peers", DIM)
+
+
+def stages_summary(stages):
+    """One-line view: stages that have progressed, with their block numbers."""
+    if not stages:
+        return ""
+    advanced = [(n, b) for n, b in stages.items() if b > 0]
+    if not advanced:
+        return c("  stages: all 0 (headers downloading)", DIM)
+    advanced.sort(key=lambda kv: kv[1], reverse=True)
+    parts = [f"{n}={format_num(b)}" for n, b in advanced[:4]]
+    return c("  stages: " + ", ".join(parts), DIM)
+
+
+def render_one(name, x, hist):
+    state = x["state"]
+    peers = x.get("peers", 0)
+    extras = []
+    if name == "Nimbus":
+        if x.get("optimistic"):
+            extras.append(c("(optimistic head — Reth not yet verifying)", YELLOW))
+        if x.get("el_offline"):
+            extras.append(c("⚠ EL OFFLINE", RED))
+    if state == "synced":
+        out = [f"  {c(name, BOLD):<14s} {c('✓ synced', GREEN)}      {c(format_num(x['current']), BOLD)}  {peers_label(peers)}"]
+    elif state == "headers":
+        out = [
+            f"  {c(name, BOLD):<14s} {c('⧗ headers', YELLOW)}    {c('downloading initial chain', DIM)}  {peers_label(peers)}",
+            f"                 {c('(per-block progress unavailable until headers validated — see docker logs)', DIM)}",
+        ]
+    elif state == "syncing" and x["target"] <= 0:
+        out = [f"  {c(name, BOLD):<14s} {c('⧗ syncing', YELLOW)}    {c('waiting for fork-choice', DIM)}  {peers_label(peers)}"]
+    elif state == "syncing":
+        pct = x["current"] / x["target"] * 100
+        r = rate_per_sec(hist)
+        eta = eta_seconds(hist, x["target"])
+        rate_s = f"{format_num(int(r))} /s" if r and r > 0 else c("stalled", RED)
+        eta_s = format_eta(eta) if eta is not None else "?"
+        stage = x.get("stage")
+        stage_s = c(f"[{stage}]", DIM) if stage else ""
+        out = [
+            f"  {c(name, BOLD):<14s} {c('⧗ syncing', YELLOW)}    {format_num(x['current'])} / {format_num(x['target'])}  {stage_s}  {peers_label(peers)}",
+            f"                 {progress_bar(pct)} {c(f'{pct:6.2f}%', BOLD)}",
+            f"                 {c(rate_s, DIM)}   ETA {c(eta_s, BOLD)}",
+        ]
+    else:
+        out = [
+            f"  {c(name, BOLD):<14s} {c('✗ ' + state, RED)}",
+            f"                 {c(x.get('err') or '', DIM)}",
+        ]
+    # Reth-only: stages summary
+    if name == "Reth" and x.get("stages"):
+        out.append(f"               {stages_summary(x['stages'])}")
+    for e in extras:
+        out.append(f"                 {e}")
+    return out
+
+
+def render(reth, nimbus, reth_hist, nim_hist):
+    print("\033[2J\033[H", end="")
+    width = 64
+    title = f"Reth + Nimbus sync"
+    ts = time.strftime("%H:%M:%S")
+    print()
+    print(f"  {c(title, BOLD)}   {c(ts, DIM)}")
+    print(f"  {c('─' * width, DIM)}")
+    print()
+    for line in render_one("Reth", reth, reth_hist):
+        print(line)
+    print()
+    for line in render_one("Nimbus", nimbus, nim_hist):
+        print(line)
+    print()
+    win_s = (len(reth_hist) - 1) * INTERVAL if len(reth_hist) > 1 else 0
+    print(f"  {c(f'window {win_s}s · refresh {INTERVAL}s · Ctrl-C to exit', DIM)}")
+    print()
+
+
+def main():
+    once = "--once" in sys.argv
+    reth_hist = deque(maxlen=WINDOW)
+    nim_hist = deque(maxlen=WINDOW)
+    try:
+        while True:
+            r = get_reth()
+            n = get_nimbus()
+            now = time.time()
+            if r["target"] > 0 or r["state"] == "syncing":
+                reth_hist.append((now, r["current"]))
+            if n["target"] > 0 or n["state"] == "syncing":
+                nim_hist.append((now, n["current"]))
+            render(r, n, reth_hist, nim_hist)
+            if once:
+                break
+            if r["state"] == "synced" and n["state"] == "synced":
+                print(f"  {c('✓ all synced.', GREEN)}\n")
+                break
+            time.sleep(INTERVAL)
+    except KeyboardInterrupt:
+        print()
+
+
+if __name__ == "__main__":
+    main()

scripts/smp-server-digitalocean-droplet/files/opt/simplex/initialize_server.sh

@@ -22,7 +22,7 @@ smp-server --version
 
 # Initialize server
 ip_address=$(curl ifconfig.me)
-smp-server init -l --ip $ip_address
+smp-server init -l --disable-web --ip $ip_address
 
 # Server fingerprint
 fingerprint=$(cat /etc/opt/simplex/fingerprint)

scripts/smp-server-digitalocean-droplet/files/opt/simplex/on_login.sh

@@ -12,6 +12,11 @@ Check SMP server status with: systemctl status smp-server
 To keep this server secure, the UFW firewall is enabled.
 All ports are BLOCKED except 22 (SSH), 443 (HTTPS), 5223 (SMP server).
 
+Embedded HTTPS web is disabled because this image does not provision
+/etc/opt/simplex/web.crt or /etc/opt/simplex/web.key. To enable it, provision
+those files, uncomment WEB https/cert/key in /etc/opt/simplex/smp-server.ini,
+and restart smp-server.
+
 ********************************************************************************
 To stop seeing this message delete line - bash /opt/simplex/on_login.sh - from /root/.bashrc
 EOF

scripts/smp-server-linode.sh

@@ -75,6 +75,9 @@ init_opts=()
 
 [[ $ENABLE_STORE_LOG == "on" ]] && init_opts+=(-l)
 
+# This script does not provision /etc/opt/simplex/web.crt or web.key.
+init_opts+=(--disable-web)
+
 ip_address=$(curl ifconfig.me)
 init_opts+=(--ip $ip_address)
 
@@ -111,6 +114,11 @@ Check SMP server status with: systemctl status smp-server
 To keep this server secure, the UFW firewall is enabled.
 All ports are BLOCKED except 22 (SSH), 443 (HTTPS), 5223 (SMP server).
 
+Embedded HTTPS web is disabled because this script does not provision
+/etc/opt/simplex/web.crt or /etc/opt/simplex/web.key. To enable it, provision
+those files, uncomment WEB https/cert/key in /etc/opt/simplex/smp-server.ini,
+and restart smp-server.
+
 ********************************************************************************
 To stop seeing this message delete line - bash /opt/simplex/on_login.sh - from /root/.bashrc
 EOF2

simplexmq.cabal

@@ -1,7 +1,7 @@
-cabal-version: 1.12
+cabal-version: 3.0
 
 name:           simplexmq
-version:        6.5.2.0
+version:        7.1.0.4
 synopsis:       SimpleXMQ message broker
 description:    This package includes <./docs/Simplex-Messaging-Server.html server>,
                 <./docs/Simplex-Messaging-Client.html client> and
@@ -16,7 +16,7 @@ homepage:       https://github.com/simplex-chat/simplexmq#readme
 author:         simplex.chat
 maintainer:     chat@simplex.chat
 copyright:      2020-2022 simplex.chat
-license:        AGPL-3
+license:        AGPL-3.0-only
 license-file:   LICENSE
 build-type:     Simple
 extra-source-files:
@@ -24,6 +24,13 @@ extra-source-files:
     CHANGELOG.md
     cbits/sha512.h
     cbits/sntrup761.h
+    cbits/blst/**/*.c
+    cbits/blst/**/*.h
+    cbits/blst/**/*.s
+    cbits/blst/**/*.S
+    cbits/blst/**/*.asm
+    cbits/libbbs/**/*.c
+    cbits/libbbs/**/*.h
     apps/common/Web/static/index.html
     apps/common/Web/static/link.html
     apps/common/Web/static/media/apk_icon.png
@@ -82,6 +89,11 @@ flag server_postgres
   manual: True
   default: False
 
+flag commoncrypto
+  description: On Apple platforms, use SecRandomCopyBytes (Security.framework) for libbbs randomness. getentropy is a non-public symbol on iOS and triggers App Store rejection (ITMS-90338).
+  manual: True
+  default: False
+
 library
   exposed-modules:
       Simplex.FileTransfer.Agent
@@ -122,6 +134,7 @@ library
       Simplex.Messaging.Crypto.File
       Simplex.Messaging.Crypto.Lazy
       Simplex.Messaging.Crypto.Ratchet
+      Simplex.Messaging.Crypto.BBS
       Simplex.Messaging.Crypto.SNTRUP761
       Simplex.Messaging.Crypto.SNTRUP761.Bindings
       Simplex.Messaging.Crypto.SNTRUP761.Bindings.Defines
@@ -130,6 +143,7 @@ library
       Simplex.Messaging.Crypto.ShortLink
       Simplex.Messaging.Encoding
       Simplex.Messaging.Encoding.String
+      Simplex.Messaging.Names.Record
       Simplex.Messaging.Notifications.Client
       Simplex.Messaging.Notifications.Protocol
       Simplex.Messaging.Notifications.Transport
@@ -138,9 +152,11 @@ library
       Simplex.Messaging.Protocol
       Simplex.Messaging.Protocol.Types
       Simplex.Messaging.Server.Expiration
+      Simplex.Messaging.Server.Information
       Simplex.Messaging.Server.QueueStore.Postgres.Config
       Simplex.Messaging.Server.QueueStore.QueueInfo
       Simplex.Messaging.ServiceScheme
+      Simplex.Messaging.SimplexName
       Simplex.Messaging.Session
       Simplex.Messaging.SystemTime
       Simplex.Messaging.TMap
@@ -175,6 +191,7 @@ library
           Simplex.Messaging.Agent.Store.Postgres.Migrations.M20251230_strict_tables
           Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260410_receive_attempts
           Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260411_service_certs
+          Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260712_address_dr_rpc
   else
       exposed-modules:
           Simplex.Messaging.Agent.Store.SQLite
@@ -227,6 +244,7 @@ library
           Simplex.Messaging.Agent.Store.SQLite.Migrations.M20251230_strict_tables
           Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260410_receive_attempts
           Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260411_service_certs
+          Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260712_address_dr_rpc
           Simplex.Messaging.Agent.Store.SQLite.Util
   if flag(client_postgres) || flag(server_postgres)
       exposed-modules:
@@ -251,7 +269,6 @@ library
           Simplex.Messaging.Server.CLI
           Simplex.Messaging.Server.Control
           Simplex.Messaging.Server.Env.STM
-          Simplex.Messaging.Server.Information
           Simplex.Messaging.Server.Main
           Simplex.Messaging.Server.Main.GitCommit
           Simplex.Messaging.Server.Main.Init
@@ -261,6 +278,8 @@ library
           Simplex.Messaging.Server.MsgStore.Journal.SharedLock
           Simplex.Messaging.Server.MsgStore.STM
           Simplex.Messaging.Server.MsgStore.Types
+          Simplex.Messaging.Server.Names
+          Simplex.Messaging.Server.Names.HttpResolver
           Simplex.Messaging.Server.NtfStore
           Simplex.Messaging.Server.Prometheus
           Simplex.Messaging.Server.QueueStore
@@ -300,11 +319,33 @@ library
   ghc-options: -Weverything -Wno-missing-exported-signatures -Wno-missing-import-lists -Wno-missed-specialisations -Wno-all-missed-specialisations -Wno-unsafe -Wno-safe -Wno-missing-local-signatures -Wno-missing-kind-signatures -Wno-missing-deriving-strategies -Wno-monomorphism-restriction -Wno-prepositive-qualified-module -Wno-implicit-prelude -Wno-missing-safe-haskell-mode -Wno-missing-export-lists -Wno-partial-fields -Wcompat -Werror=incomplete-record-updates -Werror=incomplete-patterns -Werror=incomplete-uni-patterns -Werror=missing-home-modules -Werror=missing-methods -Werror=tabs -Wredundant-constraints -Wincomplete-record-updates -Wunused-type-patterns -O2
   include-dirs:
       cbits
+      cbits/blst/bindings
+      cbits/blst/src
+      cbits/libbbs/include
+      cbits/libbbs/src
+  cc-options: -D__BLST_PORTABLE__
+  if flag(commoncrypto)
+    cc-options: -DBBS_CRYPTO_CC
+    frameworks: Security
   c-sources:
       cbits/sha512.c
       cbits/sntrup761.c
+      cbits/blst/src/server.c
+      cbits/libbbs/src/bbs.c
+      cbits/libbbs/src/bbs_ciphersuites.c
+      cbits/libbbs/src/bbs_util.c
+      cbits/libbbs/src/compat-string.c
+      cbits/libbbs/src/sha256.c
+      cbits/libbbs/src/shake256.c
+  asm-sources:
+      cbits/blst/build/assembly.S
   extra-libraries:
       crypto
+  if os(windows)
+    c-sources:
+        cbits/getentropy_win.c
+    extra-libraries:
+        bcrypt
   build-depends:
       aeson ==2.2.*
     , asn1-encoding ==0.9.*
@@ -355,7 +396,10 @@ library
     build-depends:
         case-insensitive ==1.2.*
       , hashable ==1.4.*
+      , http-client >=0.7 && <0.8
+      , http-client-tls >=0.3 && <0.4
       , ini ==0.4.1
+      , network-uri >=2.6 && <2.7
       , optparse-applicative >=0.15 && <0.17
       , process ==1.6.*
       , temporary ==1.3.*
@@ -489,6 +533,7 @@ test-suite simplexmq-test
       AgentTests.EqInstances
       AgentTests.FunctionalAPITests
       AgentTests.MigrationTests
+      AgentTests.ResolveNameTests
       AgentTests.ServerChoice
       AgentTests.ShortLinkTests
       CLITests
@@ -505,9 +550,12 @@ test-suite simplexmq-test
       CoreTests.VersionRangeTests
       FileDescriptionTests
       RemoteControl
+      NamesResolverServer
+      RSLVTests
       ServerTests
       SMPAgentClient
       SMPClient
+      SMPNamesTests
       SMPProxyTests
       Util
       XFTPAgent
@@ -588,6 +636,8 @@ test-suite simplexmq-test
     , unliftio
     , unliftio-core
     , unordered-containers
+    , wai
+    , warp
     , yaml
   default-language: Haskell2010
   if flag(server_postgres)

src/Simplex/FileTransfer/Client.hs

@@ -109,12 +109,6 @@ data XFTPClientConfig = XFTPClientConfig
     clientALPN :: Maybe [ALPN]
   }
 
-data XFTPChunkBody = XFTPChunkBody
-  { chunkSize :: Int,
-    chunkPart :: Int -> IO ByteString,
-    http2Body :: HTTP2Body
-  }
-
 data XFTPChunkSpec = XFTPChunkSpec
   { filePath :: FilePath,
     chunkOffset :: Int64,
@@ -147,7 +141,7 @@ getXFTPClient transportSession@(_, srv, _) config@XFTPClientConfig {clientALPN,
   let HTTP2Client {sessionId, sessionALPN} = http2Client
       v = VersionXFTP 1
       thServerVRange = versionToRange v
-      thParams0 = THandleParams {sessionId, blockSize = xftpBlockSize, thVersion = v, thServerVRange, thAuth = Nothing, implySessId = False, encryptBlock = Nothing, batch = True, serviceAuth = False}
+      thParams0 = THandleParams {sessionId, blockSize = xftpBlockSize, thVersion = v, thServerVRange, thAuth = Nothing, implySessId = False, encryptBlock = Nothing, serviceAuth = False, serverInfo = Nothing}
   logDebug $ "Client negotiated handshake protocol: " <> tshow sessionALPN
   thParams@THandleParams {thVersion} <- case sessionALPN of
     Just alpn

src/Simplex/FileTransfer/Client/Main.hs

@@ -14,6 +14,7 @@ module Simplex.FileTransfer.Client.Main
   ( SendOptions (..),
     CLIError (..),
     xftpClientCLI,
+    xftpClientDeprecationNotice,
     cliSendFile,
     cliSendFileOpts,
     encodeWebURI,
@@ -69,7 +70,6 @@ import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String (StrEncoding (..))
 import Simplex.Messaging.Parsers (parseAll)
 import Simplex.Messaging.Protocol (ProtoServerWithAuth (..), ProtocolServer (..), SenderId, SndPrivateAuthKey, XFTPServer, XFTPServerWithAuth)
-import Simplex.Messaging.Server.CLI (getCliCommand')
 import Simplex.Messaging.Util (groupAllOn, ifM, tshow, whenM)
 import System.Exit (exitFailure)
 import System.FilePath (splitFileName, (</>))
@@ -81,6 +81,10 @@ import UnliftIO.Directory
 xftpClientVersion :: String
 xftpClientVersion = "1.0.1"
 
+xftpClientDeprecationNotice :: String
+xftpClientDeprecationNotice =
+  "WARNING: the standalone xftp CLI is experimental and deprecated."
+
 newtype CLIError = CLIError String
   deriving (Eq, Show, Exception)
 
@@ -223,7 +227,13 @@ logCfg = LogConfig {lc_file = Nothing, lc_stderr = True}
 
 xftpClientCLI :: IO ()
 xftpClientCLI =
-  getCliCommand' cliCommandP clientVersion >>= \case
+  customExecParser
+    (prefs showHelpOnEmpty)
+    ( info
+        (helper <*> versionOption <*> cliCommandP)
+        (header (clientVersion <> "\n" <> xftpClientDeprecationNotice) <> fullDesc)
+    )
+    >>= \case
     SendFile opts -> runLogE opts $ cliSendFile opts
     ReceiveFile opts -> runLogE opts $ cliReceiveFile opts
     DeleteFile opts -> runLogE opts $ cliDeleteFile opts
@@ -231,6 +241,7 @@ xftpClientCLI =
     RandomFile opts -> cliRandomFile opts
   where
     clientVersion = "SimpleX XFTP client v" <> xftpClientVersion
+    versionOption = infoOption clientVersion (long "version" <> short 'v' <> help "Show version")
 
 runLogE :: HasField "verbose" a Bool => a -> ExceptT CLIError IO () -> IO ()
 runLogE opts a

src/Simplex/FileTransfer/Server.hs

@@ -157,7 +157,7 @@ xftpServer cfg@XFTPServerConfig {xftpPort, transportConfig, inactiveClientExpira
             reqBody <- getHTTP2Body r xftpBlockSize
             let v = VersionXFTP 1
                 thServerVRange = versionToRange v
-                thParams0 = THandleParams {sessionId, blockSize = xftpBlockSize, thVersion = v, thServerVRange, thAuth = Nothing, implySessId = False, encryptBlock = Nothing, batch = True, serviceAuth = False}
+                thParams0 = THandleParams {sessionId, blockSize = xftpBlockSize, thVersion = v, thServerVRange, thAuth = Nothing, implySessId = False, encryptBlock = Nothing, serviceAuth = False, serverInfo = Nothing}
                 req0 = XFTPTransportRequest {thParams = thParams0, request = r, reqBody, sendResponse, sniUsed, addCORS = addCORS'}
             flip runReaderT env $ case sessionALPN of
               Nothing -> processRequest req0

src/Simplex/FileTransfer/Server/Store.hs

@@ -22,11 +22,11 @@ where
 import Data.Kind (Type)
 
 import Control.Concurrent.STM
-import Control.Monad (forM, void)
+import Control.Monad
 import qualified Data.Attoparsec.ByteString.Char8 as A
 import Data.Int (Int64)
 import qualified Data.Map.Strict as M
-import Data.Maybe (catMaybes)
+import Data.Maybe (catMaybes, isJust)
 import Data.Set (Set)
 import qualified Data.Set as S
 import Data.Word (Word32)
@@ -175,8 +175,10 @@ instance FileStoreClass STMFileStore where
           pure $ Just (sId, path, size)
         else pure Nothing
 
-  getUsedStorage STMFileStore {files} =
-    M.foldl' (\acc FileRec {fileInfo = FileInfo {size}} -> acc + fromIntegral size) 0 <$> readTVarIO files
+  getUsedStorage STMFileStore {files} = foldM addSize 0 =<< readTVarIO files
+    where
+      addSize acc FileRec {fileInfo = FileInfo {size}, filePath} =
+        ifM (isJust <$> readTVarIO filePath) (pure $! acc + fromIntegral size) (pure acc)
 
   getFileCount STMFileStore {files} = M.size <$> readTVarIO files
 

src/Simplex/FileTransfer/Server/Store/Postgres.hs

@@ -164,7 +164,7 @@ instance FileStoreClass PostgresFileStore where
 
   getUsedStorage st =
     withTransaction (dbStore st) $ \db -> do
-      [Only total] <- DB.query_ db "SELECT COALESCE(SUM(file_size::BIGINT), 0)::BIGINT FROM files"
+      [Only total] <- DB.query_ db "SELECT COALESCE(SUM(file_size::BIGINT), 0)::BIGINT FROM files WHERE file_path IS NOT NULL"
       pure total
 
   getFileCount st =

src/Simplex/FileTransfer/Util.hs

@@ -1,19 +1,26 @@
 module Simplex.FileTransfer.Util
   ( uniqueCombine,
+    safeFileNameStr,
     removePath,
   )
 where
 
 import Simplex.Messaging.Util (ifM, whenM)
-import System.FilePath (splitExtensions, (</>))
+import System.FilePath (makeValid, splitExtensions, takeFileName, (</>))
 import UnliftIO
 import UnliftIO.Directory
 
+safeFileNameStr :: String -> String
+safeFileNameStr = notDots . makeValid . takeFileName
+  where
+    notDots n = if n == "." || n == ".." then "_" else n
+
+-- | The file name is sanitized, so the combined path cannot escape the folder.
 uniqueCombine :: MonadIO m => FilePath -> String -> m FilePath
 uniqueCombine filePath fileName = tryCombine (0 :: Int)
   where
     tryCombine n =
-      let (name, ext) = splitExtensions fileName
+      let (name, ext) = splitExtensions $ safeFileNameStr fileName
           suffix = if n == 0 then "" else "_" <> show n
           f = filePath </> (name <> suffix <> ext)
        in ifM (doesPathExist f) (tryCombine $ n + 1) (pure f)

src/Simplex/Messaging/Agent/Client.hs

@@ -68,6 +68,8 @@ module Simplex.Messaging.Agent.Client
     deleteQueueLink,
     secureGetQueueLink,
     getQueueLink,
+    resolveName,
+    getNextNameServer,
     enableQueueNotifications,
     EnableQueueNtfReq (..),
     enableQueuesNtfs,
@@ -267,6 +269,7 @@ import Simplex.Messaging.Protocol
     NetworkError (..),
     MsgFlags (..),
     MsgId,
+    NameRecord,
     NtfServer,
     NtfServerWithAuth,
     ProtoServer,
@@ -301,11 +304,12 @@ import Simplex.Messaging.Protocol
 import qualified Simplex.Messaging.Protocol as SMP
 import Simplex.Messaging.Protocol.Types
 import Simplex.Messaging.Server.QueueStore.QueueInfo
+import Simplex.Messaging.Server.Information (ServerPublicInfo)
 import Simplex.Messaging.Session
 import Simplex.Messaging.SystemTime
 import Simplex.Messaging.TMap (TMap)
 import qualified Simplex.Messaging.TMap as TM
-import Simplex.Messaging.Transport (HandshakeError (..), SMPServiceRole (..), SMPVersion, ServiceCredentials (..), SessionId, THClientService' (..), THandleAuth (..), THandleParams (sessionId, thAuth, thVersion), TransportError (..), TransportPeer (..), sndAuthKeySMPVersion, shortLinksSMPVersion, newNtfCredsSMPVersion)
+import Simplex.Messaging.Transport (HandshakeError (..), SMPServiceRole (..), SMPVersion, ServiceCredentials (..), SessionId, THClientService' (..), THandleAuth (..), THandleParams (sessionId, thAuth, thVersion, serverInfo), TransportError (..), TransportPeer (..), shortLinksSMPVersion, newNtfCredsSMPVersion)
 import Simplex.Messaging.Transport.Client (TransportHost (..))
 import Simplex.Messaging.Transport.Credentials
 import Simplex.Messaging.Util
@@ -381,6 +385,7 @@ data AgentClient = AgentClient
     clientId :: Int,
     agentEnv :: Env,
     proxySessTs :: TVar UTCTime,
+    serviceRequests :: TMap ConnId (TMVar (Either AgentErrorType SMP.MsgBody)),
     smpServersStats :: TMap (UserId, SMPServer) AgentSMPServerStats,
     xftpServersStats :: TMap (UserId, XFTPServer) AgentXFTPServerStats,
     ntfServersStats :: TMap (UserId, NtfServer) AgentNtfServerStats,
@@ -544,6 +549,7 @@ newAgentClient clientId InitialAgentServers {smp, ntf, xftp, netCfg, useServices
   invLocks <- TM.emptyIO
   deleteLock <- createLockIO
   smpSubWorkers <- TM.emptyIO
+  serviceRequests <- TM.emptyIO
   smpServersStats <- TM.emptyIO
   xftpServersStats <- TM.emptyIO
   ntfServersStats <- TM.emptyIO
@@ -589,6 +595,7 @@ newAgentClient clientId InitialAgentServers {smp, ntf, xftp, netCfg, useServices
         clientId,
         agentEnv,
         proxySessTs,
+        serviceRequests,
         smpServersStats,
         xftpServersStats,
         ntfServersStats,
@@ -674,8 +681,7 @@ getSMPServerClient :: AgentClient -> NetworkRequestMode -> SMPTransportSession -
 getSMPServerClient c@AgentClient {active, smpClients, workerSeq} nm tSess = do
   unlessM (readTVarIO active) $ throwE INACTIVE
   ts <- liftIO getCurrentTime
-  atomically (getSessVar workerSeq tSess smpClients ts)
-    >>= either newClient (waitForProtocolClient c nm tSess smpClients)
+  withGetSessVar workerSeq tSess smpClients ts newClient (waitForProtocolClient c nm tSess smpClients)
   where
     newClient v = do
       prs <- liftIO TM.emptyIO
@@ -686,33 +692,29 @@ getSMPProxyClient c@AgentClient {active, smpClients, smpProxiedRelays, workerSeq
   unlessM (readTVarIO active) $ throwE INACTIVE
   proxySrv <- maybe (getNextServer c userId proxySrvs [destSrv]) pure proxySrv_
   ts <- liftIO getCurrentTime
-  atomically (getClientVar proxySrv ts) >>= \(tSess, auth, v) ->
-    either (newProxyClient tSess auth ts) (waitForProxyClient tSess auth) v
+  (tSess, auth) <- atomically $ proxiedTransportSession proxySrv
+  withGetSessVar workerSeq tSess smpClients ts (newProxyClient tSess auth ts) (waitForProxyClient tSess auth)
   where
-    getClientVar :: SMPServerWithAuth -> UTCTime -> STM (SMPTransportSession, Maybe SMP.BasicAuth, Either SMPClientVar SMPClientVar)
-    getClientVar proxySrv ts = do
+    proxiedTransportSession :: SMPServerWithAuth -> STM (SMPTransportSession, Maybe SMP.BasicAuth)
+    proxiedTransportSession proxySrv = do
       ProtoServerWithAuth srv auth <- TM.lookup destSess smpProxiedRelays >>= maybe (TM.insert destSess proxySrv smpProxiedRelays $> proxySrv) pure
-      let tSess = (userId, srv, qId)
-      (tSess,auth,) <$> getSessVar workerSeq tSess smpClients ts
+      pure ((userId, srv, qId), auth)
     newProxyClient :: SMPTransportSession -> Maybe SMP.BasicAuth -> UTCTime -> SMPClientVar -> AM (SMPConnectedClient, Either AgentErrorType ProxiedRelay)
     newProxyClient tSess auth ts v = do
       prs <- liftIO TM.emptyIO
-      -- we do not need to check if it is a new proxied relay session,
-      -- as the client is just created and there are no sessions yet
-      rv <- atomically $ either id id <$> getSessVar workerSeq destSrv prs ts
       clnt <- smpConnectClient c nm tSess prs v
-      (clnt,) <$> newProxiedRelay clnt auth rv
+      -- the relay var is always new (the client is just created and has no sessions yet)
+      sess <- withGetSessVar workerSeq destSrv prs ts (newProxiedRelay clnt auth) (waitForProxiedRelay tSess)
+      pure (clnt, sess)
     waitForProxyClient :: SMPTransportSession -> Maybe SMP.BasicAuth -> SMPClientVar -> AM (SMPConnectedClient, Either AgentErrorType ProxiedRelay)
     waitForProxyClient tSess auth v = do
       clnt@(SMPConnectedClient _ prs) <- waitForProtocolClient c nm tSess smpClients v
       ts <- liftIO getCurrentTime
-      sess <-
-        atomically (getSessVar workerSeq destSrv prs ts)
-          >>= either (newProxiedRelay clnt auth) (waitForProxiedRelay tSess)
+      sess <- withGetSessVar workerSeq destSrv prs ts (newProxiedRelay clnt auth) (waitForProxiedRelay tSess)
       pure (clnt, sess)
     newProxiedRelay :: SMPConnectedClient -> Maybe SMP.BasicAuth -> ProxiedRelayVar -> AM (Either AgentErrorType ProxiedRelay)
     newProxiedRelay (SMPConnectedClient smp prs) proxyAuth rv =
-      tryAllErrors (liftClient SMP (clientServer smp) $ connectSMPProxiedRelay smp nm destSrv proxyAuth) >>= \case
+      tryAllErrors (liftClient proxyRelayError (clientServer smp) $ connectSMPProxiedRelay smp nm destSrv proxyAuth) >>= \case
         Right sess -> do
           atomically $ putTMVar (sessionVar rv) (Right sess)
           pure $ Right sess
@@ -723,6 +725,18 @@ getSMPProxyClient c@AgentClient {active, smpClients, smpProxiedRelays, workerSeq
               TM.delete destSess smpProxiedRelays
             putTMVar (sessionVar rv) (Left e)
             pure $ Left e
+      where
+        -- proxy reports BROKER errors about the relay, not about its own connection,
+        -- so they include both addresses, same as PFWD errors.
+        proxyRelayError :: HostName -> ErrorType -> AgentErrorType
+        proxyRelayError proxyHost = \case
+          e@(SMP.PROXY (SMP.BROKER _)) ->
+            PROXY
+              { proxyServer = protocolClientServer smp,
+                relayServer = B.unpack $ strEncode destSrv,
+                proxyErr = ProxyProtocolError e
+              }
+          e -> SMP proxyHost e
     waitForProxiedRelay :: SMPTransportSession -> ProxiedRelayVar -> AM (Either AgentErrorType ProxiedRelay)
     waitForProxiedRelay (_, srv, _) rv = do
       NetworkConfig {tcpConnectTimeout} <- getNetworkConfig c
@@ -846,10 +860,7 @@ getNtfServerClient :: AgentClient -> NetworkRequestMode -> NtfTransportSession -
 getNtfServerClient c@AgentClient {active, ntfClients, workerSeq, proxySessTs, presetDomains} nm tSess@(_, srv, _) = do
   unlessM (readTVarIO active) $ throwE INACTIVE
   ts <- liftIO getCurrentTime
-  atomically (getSessVar workerSeq tSess ntfClients ts)
-    >>= either
-      (newProtocolClient c tSess ntfClients connectClient)
-      (waitForProtocolClient c nm tSess ntfClients)
+  withGetSessVar workerSeq tSess ntfClients ts (newProtocolClient c tSess ntfClients connectClient) (waitForProtocolClient c nm tSess ntfClients)
   where
     connectClient :: NtfClientVar -> AM NtfClient
     connectClient v = do
@@ -870,10 +881,7 @@ getXFTPServerClient :: AgentClient -> XFTPTransportSession -> AM XFTPClient
 getXFTPServerClient c@AgentClient {active, xftpClients, workerSeq, proxySessTs, presetDomains} tSess@(_, srv, _) = do
   unlessM (readTVarIO active) $ throwE INACTIVE
   ts <- liftIO getCurrentTime
-  atomically (getSessVar workerSeq tSess xftpClients ts)
-    >>= either
-      (newProtocolClient c tSess xftpClients connectClient)
-      (waitForProtocolClient c NRMBackground tSess xftpClients)
+  withGetSessVar workerSeq tSess xftpClients ts (newProtocolClient c tSess xftpClients connectClient) (waitForProtocolClient c NRMBackground tSess xftpClients)
   where
     connectClient :: XFTPClientVar -> AM XFTPClient
     connectClient v = do
@@ -1289,7 +1297,7 @@ data ProtocolTestFailure = ProtocolTestFailure
   }
   deriving (Eq, Show)
 
-runSMPServerTest :: AgentClient -> NetworkRequestMode -> UserId -> SMPServerWithAuth -> AM' (Maybe ProtocolTestFailure)
+runSMPServerTest :: AgentClient -> NetworkRequestMode -> UserId -> SMPServerWithAuth -> AM' (Either ProtocolTestFailure (Maybe (Either String ServerPublicInfo)))
 runSMPServerTest c@AgentClient {presetDomains} nm userId (ProtoServerWithAuth srv auth) = do
   cfg <- getClientConfig c smpCfg
   C.AuthAlg ra <- asks $ rcvAuthAlg . config
@@ -1311,8 +1319,8 @@ runSMPServerTest c@AgentClient {presetDomains} nm userId (ProtoServerWithAuth sr
               _ -> secureSMPQueue smp nm rpKey rcvId sKey
           liftError (testErr TSDeleteQueue) $ deleteSMPQueue smp nm rpKey rcvId
         ok <- netTimeoutInt (tcpTimeout $ networkConfig cfg) nm `timeout` closeProtocolClient smp
-        pure $ either Just (const Nothing) r <|> maybe (Just (ProtocolTestFailure TSDisconnect $ BROKER addr TIMEOUT)) (const Nothing) ok
-      Left e -> pure (Just $ testErr TSConnect e)
+        pure $ r >> maybe (Left (ProtocolTestFailure TSDisconnect $ BROKER addr TIMEOUT)) (const $ Right $ serverInfo (thParams smp)) ok
+      Left e -> pure $ Left (testErr TSConnect e)
   where
     addr = B.unpack $ strEncode srv
     testErr :: ProtocolTestStep -> SMPClientError -> ProtocolTestFailure
@@ -1512,9 +1520,7 @@ newRcvQueue_ c nm userId connId (ProtoServerWithAuth srv auth) vRange cqrd enabl
           if sndId == sndId' && lnkId == lnkId'
             then pure $ Just $ ShortLinkCreds lnkId linkKey privSigKey Nothing (fst d)
             else newErr "different sender or link IDs"
-      (_, Nothing) -> case linkId of
-        Nothing | v < sndAuthKeySMPVersion -> pure Nothing
-        _ -> newErr "unexpected link ID"
+      (_, Nothing) -> newErr "unexpected link ID"
       _ -> newErr "unexpected queue mode"
       where
         v = thVersion thParams'
@@ -1921,17 +1927,10 @@ sendConfirmation c nm sq@SndQueue {userId, server, connId, sndId, queueMode, snd
   sendOrProxySMPMessage c nm userId server connId "<CONF>" spKey sndId (MsgFlags {notification = True}) msg
 sendConfirmation _ _ _ _ = throwE $ INTERNAL "sendConfirmation called without snd_queue public key(s) in the database"
 
-sendInvitation :: AgentClient -> NetworkRequestMode -> UserId -> ConnId -> Compatible SMPQueueInfo -> Compatible VersionSMPA -> ConnectionRequestUri 'CMInvitation -> ConnInfo -> AM (Maybe SMPServer)
-sendInvitation c nm userId connId (Compatible (SMPQueueInfo v SMPQueueAddress {smpServer, senderId, dhPublicKey})) (Compatible agentVersion) connReq connInfo = do
-  msg <- mkInvitation
+sendInvitation :: AgentClient -> NetworkRequestMode -> UserId -> ConnId -> Compatible SMPQueueInfo -> AgentMsgEnvelope -> AM (Maybe SMPServer)
+sendInvitation c nm userId connId (Compatible (SMPQueueInfo v SMPQueueAddress {smpServer, senderId, dhPublicKey})) agentEnvelope = do
+  msg <- agentCbEncryptOnce v dhPublicKey . smpEncode $ SMP.ClientMessage SMP.PHEmpty (smpEncode agentEnvelope)
   sendOrProxySMPMessage c nm userId smpServer connId "<INV>" Nothing senderId (MsgFlags {notification = True}) msg
-  where
-    mkInvitation :: AM ByteString
-    -- this is only encrypted with per-queue E2E, not with double ratchet
-    mkInvitation = do
-      let agentEnvelope = AgentInvitation {agentVersion, connReq, connInfo}
-      agentCbEncryptOnce v dhPublicKey . smpEncode $
-        SMP.ClientMessage SMP.PHEmpty (smpEncode agentEnvelope)
 
 getQueueMessage :: AgentClient -> RcvQueue -> AM (Maybe SMPMsgMeta)
 getQueueMessage c rq@RcvQueue {server, rcvId, rcvPrivateKey} = do
@@ -1951,7 +1950,7 @@ getQueueMessage c rq@RcvQueue {server, rcvId, rcvPrivateKey} = do
 
 decryptSMPMessage :: RcvQueue -> SMP.RcvMessage -> AM SMP.ClientRcvMsgBody
 decryptSMPMessage rq SMP.RcvMessage {msgId, msgBody = SMP.EncRcvMsgBody body} =
-  liftEither $ parse SMP.clientRcvMsgBodyP (AGENT A_MESSAGE) =<< decrypt body
+  liftEither $ parse SMP.clientRcvMsgBodyP (AGENT $ A_MESSAGE "decrypt message") =<< decrypt body
   where
     decrypt = agentCbDecrypt (rcvDhSecret rq) (C.cbNonce msgId)
 
@@ -1990,6 +1989,28 @@ getQueueLink c nm userId server lnkId =
     getViaProxy smp proxySess = proxyGetSMPQueueLink smp nm proxySess lnkId
     getDirectly smp = getSMPQueueLink smp nm lnkId
 
+-- | Resolve a public-namespace name. Prefers PFWD (hides client IP from the
+-- resolver) and falls back to a direct send when the proxy is unavailable
+-- (faster but exposes the client IP). Mode selection is delegated to
+-- `sendOrProxySMPCommand`, which honours the network config (SPMNever etc.).
+resolveName :: AgentClient -> NetworkRequestMode -> UserId -> SMPServer -> SimplexDomain -> AM NameRecord
+resolveName c nm userId server domain =
+  snd <$> sendOrProxySMPCommand c nm userId server "" "RSLV" NoEntity resolveViaProxy resolveDirectly
+  where
+    resolveViaProxy smp proxySess = proxyResolveName smp nm proxySess domain
+    resolveDirectly smp = directResolveName smp nm domain
+
+-- | Pick a names-capable server for the user (the agent owns server selection,
+-- accounting for the names role). nameSrvs is opt-in (a plain list); empty means
+-- no server resolves names - a declared agent error, never a fallback.
+getNextNameServer :: AgentClient -> UserId -> AM SMPServer
+getNextNameServer c userId =
+  liftIO (TM.lookupIO userId (userServers c :: TMap UserId (UserServers 'PSMP))) >>= \case
+    Just UserServers {nameSrvs} -> case L.nonEmpty nameSrvs of
+      Just srvs -> protoServer <$> pickServer srvs
+      Nothing -> throwE NO_NAME_SERVERS
+    Nothing -> throwE $ INTERNAL "unknown userId - no user servers"
+
 enableQueueNotifications :: AgentClient -> RcvQueue -> SMP.NtfPublicAuthKey -> SMP.RcvNtfPublicDhKey -> AM (SMP.NotifierId, SMP.RcvNtfPublicDhKey)
 enableQueueNotifications c rq@RcvQueue {rcvId, rcvPrivateKey} notifierKey rcvNtfPublicDhKey =
   withSMPClient c NRMBackground rq "NKEY <nkey>" $ \smp ->
@@ -2233,7 +2254,7 @@ agentCbDecrypt dhSecret nonce msg =
 cryptoError :: C.CryptoError -> AgentErrorType
 cryptoError = \case
   C.CryptoLargeMsgError -> CMD LARGE "CryptoLargeMsgError"
-  C.CryptoHeaderError _ -> AGENT A_MESSAGE -- parsing error
+  C.CryptoHeaderError e -> AGENT $ A_MESSAGE $ "parse msg header " <> e
   C.CERatchetDuplicateMessage -> AGENT $ A_DUPLICATE Nothing
   C.AESDecryptError -> c DECRYPT_AES
   C.CBDecryptError -> c DECRYPT_CB

src/Simplex/Messaging/Agent/Env/SQLite.hs

@@ -105,12 +105,13 @@ data ServerCfg p = ServerCfg
 
 data ServerRoles = ServerRoles
   { storage :: Bool,
-    proxy :: Bool
+    proxy :: Bool,
+    names :: Bool
   }
   deriving (Show)
 
 allRoles :: ServerRoles
-allRoles = ServerRoles True True
+allRoles = ServerRoles True True True
 
 presetServerCfg :: Bool -> ServerRoles -> Maybe OperatorId -> ProtoServerWithAuth p -> ServerCfg p
 presetServerCfg enabled roles operator server =
@@ -119,6 +120,9 @@ presetServerCfg enabled roles operator server =
 data UserServers p = UserServers
   { storageSrvs :: NonEmpty (Maybe OperatorId, ProtoServerWithAuth p),
     proxySrvs :: NonEmpty (Maybe OperatorId, ProtoServerWithAuth p),
+    -- name resolution is opt-in: a plain list (NOT NonEmpty, no fallback-to-all).
+    -- Empty = no servers resolve names = a clean agent error, never falls back.
+    nameSrvs :: [(Maybe OperatorId, ProtoServerWithAuth p)],
     knownHosts :: Set TransportHost
   }
 
@@ -126,9 +130,10 @@ type OperatorId = Int64
 
 -- This function sets all servers as enabled in case all passed servers are disabled.
 mkUserServers :: NonEmpty (ServerCfg p) -> UserServers p
-mkUserServers srvs = UserServers {storageSrvs = filterSrvs storage, proxySrvs = filterSrvs proxy, knownHosts}
+mkUserServers srvs = UserServers {storageSrvs = filterSrvs storage, proxySrvs = filterSrvs proxy, nameSrvs, knownHosts}
   where
     filterSrvs role = L.map (\ServerCfg {operator, server} -> (operator, server)) $ fromMaybe srvs $ L.nonEmpty $ L.filter (\ServerCfg {enabled, roles} -> enabled && role roles) srvs
+    nameSrvs = map (\ServerCfg {operator, server} -> (operator, server)) $ L.filter (\ServerCfg {enabled, roles} -> enabled && names roles) srvs
     knownHosts = S.unions $ L.map (\ServerCfg {server = ProtoServerWithAuth srv _} -> serverHosts srv) srvs
 
 serverHosts :: ProtocolServer p -> Set TransportHost
@@ -148,6 +153,8 @@ data AgentConfig = AgentConfig
     userNetworkInterval :: Int,
     userOfflineDelay :: NominalDiffTime,
     messageTimeout :: NominalDiffTime,
+    serviceRequestTimeout :: NominalDiffTime, -- client side: default time the client waits for a service response (overridable per request)
+    serviceResponseTimeout :: NominalDiffTime, -- service side: time a received service request is valid to respond to
     connDeleteDeliveryTimeout :: NominalDiffTime,
     helloTimeout :: NominalDiffTime,
     quotaExceededTimeout :: NominalDiffTime,
@@ -165,6 +172,7 @@ data AgentConfig = AgentConfig
     xftpConsecutiveRetries :: Int,
     xftpMaxRecipientsPerRequest :: Int,
     deleteErrorCount :: Int,
+    keepAddressKeys :: Int,
     ntfCron :: Word16,
     ntfBatchSize :: Int,
     ntfSubFirstCheckInterval :: NominalDiffTime,
@@ -223,6 +231,8 @@ defaultAgentConfig =
       userNetworkInterval = 1800_000000, -- 30 minutes, should be less than Int32 max value
       userOfflineDelay = 2, -- if network offline event happens in less than 2 seconds after it was set online, it is ignored
       messageTimeout = 2 * nominalDay,
+      serviceRequestTimeout = 30,
+      serviceResponseTimeout = 180,
       connDeleteDeliveryTimeout = 2 * nominalDay,
       helloTimeout = 2 * nominalDay,
       quotaExceededTimeout = 7 * nominalDay,
@@ -240,6 +250,7 @@ defaultAgentConfig =
       xftpConsecutiveRetries = 3,
       xftpMaxRecipientsPerRequest = 200,
       deleteErrorCount = 10,
+      keepAddressKeys = 3,
       ntfCron = 20, -- minutes
       ntfBatchSize = 150,
       ntfSubFirstCheckInterval = nominalDay,

src/Simplex/Messaging/Agent/Protocol.hs

@@ -1,6 +1,7 @@
 {-# LANGUAGE DataKinds #-}
 {-# LANGUAGE DeriveAnyClass #-}
 {-# LANGUAGE DerivingStrategies #-}
+{-# LANGUAGE DerivingVia #-}
 {-# LANGUAGE DuplicateRecordFields #-}
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE GADTs #-}
@@ -40,12 +41,8 @@ module Simplex.Messaging.Agent.Protocol
     VersionSMPA,
     VersionRangeSMPA,
     pattern VersionSMPA,
-    duplexHandshakeSMPAgentVersion,
-    ratchetSyncSMPAgentVersion,
-    deliveryRcptsSMPAgentVersion,
-    pqdrSMPAgentVersion,
-    sndAuthKeySMPAgentVersion,
     ratchetOnConfSMPAgentVersion,
+    rpcAddressSMPAgentVersion,
     currentSMPAgentVersion,
     supportedSMPAgentVRange,
     e2eEncConnInfoLength,
@@ -54,8 +51,10 @@ module Simplex.Messaging.Agent.Protocol
     -- * SMP agent protocol types
     ConnInfo,
     SndQueueSecured,
+    UseRatchetKeys,
     AEntityId,
     ACommand (..),
+    JoinRequest (..),
     AEvent (..),
     AEvt (..),
     ACommandTag (..),
@@ -80,6 +79,7 @@ module Simplex.Messaging.Agent.Protocol
     SMPConfirmation (..),
     AgentMsgEnvelope (..),
     AgentMessage (..),
+    RequestSignature (..),
     AgentMessageType (..),
     APrivHeader (..),
     AMessage (..),
@@ -107,6 +107,9 @@ module Simplex.Messaging.Agent.Protocol
     ConnectionModeI (..),
     ConnectionRequestUri (..),
     AConnectionRequestUri (..),
+    BinaryConnectionRequestUri (..),
+    ABinaryConnectionRequestUri (..),
+    binaryConnReq,
     ShortLinkCreds (..),
     ConnReqUriData (..),
     CRClientData,
@@ -118,10 +121,18 @@ module Simplex.Messaging.Agent.Protocol
     UserConnLinkData (..),
     UserContactData (..),
     UserLinkData (..),
+    AddressRatchetKeys,
+    NewRatchetKeys,
+    DRInvitation (..),
+    RatchetKeyId (..),
     OwnerAuth (..),
     OwnerId,
     ConnectionLink (..),
     AConnectionLink (..),
+    SimplexNameInfo (..),
+    SimplexDomain (..),
+    SimplexTLD (..),
+    SimplexNameType (..),
     ConnShortLink (..),
     AConnShortLink (..),
     CreatedConnLink (..),
@@ -133,16 +144,21 @@ module Simplex.Messaging.Agent.Protocol
     validateOwners,
     validateLinkOwners,
     sameConnReqContact,
+    sameConnShortLink,
     sameShortLinkContact,
+    sameShortLinkInv,
     simplexChat,
     connReqUriP',
     simplexConnReqUri,
     simplexShortLink,
+    fullDomainName,
+    shortNameInfoStr,
     AgentErrorType (..),
     CommandErrorType (..),
     ConnectionErrorType (..),
     BrokerErrorType (..),
     SMPAgentError (..),
+    AgentServiceError (..),
     DroppedMsg (..),
     AgentCryptoError (..),
     cryptoErrToSyncState,
@@ -192,6 +208,7 @@ import qualified Data.Attoparsec.ByteString.Char8 as A
 import qualified Data.ByteString.Base64.URL as B64
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
+import qualified Data.ByteString.Lazy as LB
 import Data.Char (toLower, toUpper)
 import Data.Foldable (find)
 import Data.Functor (($>))
@@ -222,14 +239,17 @@ import Simplex.Messaging.Crypto.Ratchet
   ( InitialKeys (..),
     PQEncryption (..),
     PQSupport,
+    RatchetX448,
     RcvE2ERatchetParams,
     RcvE2ERatchetParamsUri,
     SndE2ERatchetParams,
+    RcvE2EPrivRatchetParams,
     pattern PQSupportOff,
     pattern PQSupportOn,
   )
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
+import Simplex.Messaging.SimplexName (SimplexDomain (..), SimplexNameInfo (..), SimplexNameType (..), SimplexTLD (..), fullDomainName, shortNameInfoStr)
 import Simplex.Messaging.Parsers
 import Simplex.Messaging.Protocol
   ( AProtocolType,
@@ -280,6 +300,7 @@ import UnliftIO.Exception (Exception)
 -- 5 - post-quantum double ratchet (3/14/2024)
 -- 6 - secure reply queues with provided keys (6/14/2024)
 -- 7 - initialize ratchet on processing confirmation (7/18/2024)
+-- 8 - agent RPC and double ratchet PQ encryption from first message to contact address (8/01/2026)
 
 data SMPAgentVersion
 
@@ -292,29 +313,20 @@ type VersionRangeSMPA = VersionRange SMPAgentVersion
 pattern VersionSMPA :: Word16 -> VersionSMPA
 pattern VersionSMPA v = Version v
 
-duplexHandshakeSMPAgentVersion :: VersionSMPA
-duplexHandshakeSMPAgentVersion = VersionSMPA 2
-
-ratchetSyncSMPAgentVersion :: VersionSMPA
-ratchetSyncSMPAgentVersion = VersionSMPA 3
-
-deliveryRcptsSMPAgentVersion :: VersionSMPA
-deliveryRcptsSMPAgentVersion = VersionSMPA 4
-
-pqdrSMPAgentVersion :: VersionSMPA
-pqdrSMPAgentVersion = VersionSMPA 5
-
-sndAuthKeySMPAgentVersion :: VersionSMPA
-sndAuthKeySMPAgentVersion = VersionSMPA 6
+_sndAuthKeySMPAgentVersion :: VersionSMPA
+_sndAuthKeySMPAgentVersion = VersionSMPA 6
 
 ratchetOnConfSMPAgentVersion :: VersionSMPA
 ratchetOnConfSMPAgentVersion = VersionSMPA 7
 
+rpcAddressSMPAgentVersion :: VersionSMPA
+rpcAddressSMPAgentVersion = VersionSMPA 8
+
 minSupportedSMPAgentVersion :: VersionSMPA
-minSupportedSMPAgentVersion = duplexHandshakeSMPAgentVersion
+minSupportedSMPAgentVersion = _sndAuthKeySMPAgentVersion
 
 currentSMPAgentVersion :: VersionSMPA
-currentSMPAgentVersion = VersionSMPA 7
+currentSMPAgentVersion = VersionSMPA 8
 
 supportedSMPAgentVRange :: VersionRangeSMPA
 supportedSMPAgentVRange = mkVersionRange minSupportedSMPAgentVersion currentSMPAgentVersion
@@ -322,17 +334,17 @@ supportedSMPAgentVRange = mkVersionRange minSupportedSMPAgentVersion currentSMPA
 -- it is shorter to allow all handshake headers,
 -- including E2E (double-ratchet) parameters and
 -- signing key of the sender for the server
-e2eEncConnInfoLength :: VersionSMPA -> PQSupport -> Int
-e2eEncConnInfoLength v = \case
+e2eEncConnInfoLength :: PQSupport -> Int
+e2eEncConnInfoLength = \case
   -- reduced by 3726 (roughly the increase of message ratchet header size + key and ciphertext in reply link)
-  PQSupportOn | v >= pqdrSMPAgentVersion -> 11106
-  _ -> 14832
+  PQSupportOn -> 11106
+  PQSupportOff -> 14832
 
-e2eEncAgentMsgLength :: VersionSMPA -> PQSupport -> Int
-e2eEncAgentMsgLength v = \case
+e2eEncAgentMsgLength :: PQSupport -> Int
+e2eEncAgentMsgLength = \case
   -- reduced by 2222 (the increase of message ratchet header size)
-  PQSupportOn | v >= pqdrSMPAgentVersion -> 13618
-  _ -> 15840
+  PQSupportOn -> 13618
+  PQSupportOff -> 15840
 
 -- | SMP agent event
 type ATransmission = (ACorrId, AEntityId, AEvt)
@@ -384,13 +396,18 @@ type ConnInfo = ByteString
 
 type SndQueueSecured = Bool
 
+type UseRatchetKeys = Bool
+
 -- | Parameterized type for SMP agent events
 data AEvent (e :: AEntity) where
   INV :: AConnectionRequestUri -> AEvent AEConn
   LINK :: ConnShortLink 'CMContact -> UserConnLinkData 'CMContact -> AEvent AEConn
-  LDATA :: FixedLinkData 'CMContact -> ConnLinkData 'CMContact -> AEvent AEConn
+  LDATA :: FixedLinkData 'CMContact -> ConnLinkData 'CMContact -> ConnectionRequestUri 'CMContact -> AEvent AEConn
   CONF :: ConfirmationId -> PQSupport -> [SMPServer] -> ConnInfo -> AEvent AEConn -- ConnInfo is from sender, [SMPServer] will be empty only in v1 handshake
-  REQ :: InvitationId -> PQSupport -> NonEmpty SMPServer -> ConnInfo -> AEvent AEConn -- ConnInfo is from sender
+  REQ :: InvitationId -> PQSupport -> NonEmpty SMPServer -> ConnInfo -> Bool -> AEvent AEConn -- ConnInfo is from sender; Bool - rejection reason can be sent
+  SREQ :: InvitationId -> Maybe C.PublicKeyEd25519 -> MsgBody -> AEvent AEConn
+  SSENT :: AgentMsgId -> Maybe SMPServer -> AEvent AEConn
+  RJCT :: ConnInfo -> AEvent AEConn
   INFO :: PQSupport -> ConnInfo -> AEvent AEConn
   CON :: PQEncryption -> AEvent AEConn -- notification that connection is established
   END :: AEvent AEConn
@@ -445,15 +462,15 @@ instance Eq AEvtTag where
 deriving instance Show AEvtTag
 
 data ACommand
-  = NEW Bool AConnectionMode InitialKeys SubscriptionMode -- response INV
+  = NEW Bool AConnectionMode InitialKeys SubscriptionMode UseRatchetKeys -- response INV
   | LSET (UserConnLinkData 'CMContact) (Maybe CRClientData) -- response LINK
   | LGET (ConnShortLink 'CMContact) -- response LDATA
-  | JOIN Bool AConnectionRequestUri PQSupport SubscriptionMode ConnInfo
+  | JOIN JoinRequest SubscriptionMode ConnInfo
   | LET ConfirmationId ConnInfo -- ConnInfo is from client
   | ACK AgentMsgId (Maybe MsgReceiptInfo)
   | SWCH
   | DEL
-  deriving (Eq, Show)
+  deriving (Show)
 
 data ACommandTag
   = NEW_
@@ -472,6 +489,9 @@ data AEventTag (e :: AEntity) where
   LDATA_ :: AEventTag AEConn
   CONF_ :: AEventTag AEConn
   REQ_ :: AEventTag AEConn
+  SREQ_ :: AEventTag AEConn
+  SSENT_ :: AEventTag AEConn
+  RJCT_ :: AEventTag AEConn
   INFO_ :: AEventTag AEConn
   CON_ :: AEventTag AEConn
   END_ :: AEventTag AEConn
@@ -535,6 +555,9 @@ aEventTag = \case
   LDATA {} -> LDATA_
   CONF {} -> CONF_
   REQ {} -> REQ_
+  SREQ {} -> SREQ_
+  SSENT {} -> SSENT_
+  RJCT {} -> RJCT_
   INFO {} -> INFO_
   CON _ -> CON_
   END -> END_
@@ -616,16 +639,22 @@ instance FromJSON RcvSwitchStatus where
 data SndSwitchStatus
   = SSSendingQKEY
   | SSSendingQTEST
+  | SSSecuringQueue
+  | SSSendingQEND
   deriving (Eq, Show)
 
 instance StrEncoding SndSwitchStatus where
   strEncode = \case
     SSSendingQKEY -> "sending_qkey"
     SSSendingQTEST -> "sending_qtest"
+    SSSecuringQueue -> "securing_queue"
+    SSSendingQEND -> "sending_qend"
   strP =
     A.takeTill (== ' ') >>= \case
       "sending_qkey" -> pure SSSendingQKEY
       "sending_qtest" -> pure SSSendingQTEST
+      "securing_queue" -> pure SSSecuringQueue
+      "sending_qend" -> pure SSSendingQEND
       _ -> fail "bad SndSwitchStatus"
 
 instance ToField SndSwitchStatus where toField = toField . decodeLatin1 . strEncode
@@ -834,6 +863,12 @@ data AgentMsgEnvelope
         connReq :: ConnectionRequestUri 'CMInvitation,
         connInfo :: ByteString -- this message is only encrypted with per-queue E2E, not with double ratchet,
       }
+  | AgentContactRequest -- DR request to a contact address that published DR keys: a contact invitation or a service (RPC) request
+      { agentVersion :: VersionSMPA,
+        e2eSndParams :: SndE2ERatchetParams 'C.X448,
+        ratchetKeyId :: RatchetKeyId,
+        encConnInfo :: ByteString
+      }
   | AgentRatchetKey
       { agentVersion :: VersionSMPA,
         e2eEncryption :: RcvE2ERatchetParams 'C.X448,
@@ -849,6 +884,8 @@ instance Encoding AgentMsgEnvelope where
       smpEncode (agentVersion, 'M', Tail encAgentMessage)
     AgentInvitation {agentVersion, connReq, connInfo} ->
       smpEncode (agentVersion, 'I', Large $ strEncode connReq, Tail connInfo)
+    AgentContactRequest {agentVersion, e2eSndParams, ratchetKeyId, encConnInfo} ->
+      smpEncode (agentVersion, 'A', e2eSndParams, ratchetKeyId, Tail encConnInfo)
     AgentRatchetKey {agentVersion, e2eEncryption, info} ->
       smpEncode (agentVersion, 'R', e2eEncryption, Tail info)
   smpP = do
@@ -864,12 +901,22 @@ instance Encoding AgentMsgEnvelope where
         connReq <- strDecode . unLarge <$?> smpP
         Tail connInfo <- smpP
         pure AgentInvitation {agentVersion, connReq, connInfo}
+      'A' -> do
+        (e2eSndParams, ratchetKeyId, Tail encConnInfo) <- smpP
+        pure AgentContactRequest {agentVersion, e2eSndParams, ratchetKeyId, encConnInfo}
       'R' -> do
         e2eEncryption <- smpP
         Tail info <- smpP
         pure AgentRatchetKey {agentVersion, e2eEncryption, info}
       _ -> fail "bad AgentMsgEnvelope"
 
+data RequestSignature = RequestSignature C.PublicKeyEd25519 (C.Signature 'C.Ed25519)
+  deriving (Eq, Show)
+
+instance Encoding RequestSignature where
+  smpEncode (RequestSignature k sig) = smpEncode (k, sig)
+  smpP = RequestSignature <$> smpP <*> smpP
+
 -- SMP agent message formats (after double ratchet decryption,
 -- or in case of AgentInvitation - in plain text body)
 -- AgentRatchetInfo is not encrypted with double ratchet, but with per-queue E2E encryption
@@ -881,6 +928,9 @@ data AgentMessage
     AgentConnInfoReply (NonEmpty SMPQueueInfo) ConnInfo
   | AgentRatchetInfo ByteString
   | AgentMessage APrivHeader AMessage
+  | AgentServiceRequest (NonEmpty SMPQueueInfo) (Maybe RequestSignature) MsgBody
+  | AgentServiceResponse MsgBody
+  | AgentRejection ByteString
   deriving (Show)
 
 instance Encoding AgentMessage where
@@ -889,12 +939,18 @@ instance Encoding AgentMessage where
     AgentConnInfoReply smpQueues cInfo -> smpEncode ('D', smpQueues, Tail cInfo) -- 'D' stands for "duplex"
     AgentRatchetInfo info -> smpEncode ('R', Tail info)
     AgentMessage hdr aMsg -> smpEncode ('M', hdr, aMsg)
+    AgentServiceRequest qs sig_ body -> smpEncode ('A', qs, sig_, Tail body)
+    AgentServiceResponse body -> smpEncode ('P', Tail body)
+    AgentRejection reason -> smpEncode ('J', Tail reason)
   smpP =
     smpP >>= \case
       'I' -> AgentConnInfo . unTail <$> smpP
       'D' -> AgentConnInfoReply <$> smpP <*> (unTail <$> smpP)
       'R' -> AgentRatchetInfo . unTail <$> smpP
       'M' -> AgentMessage <$> smpP <*> smpP
+      'A' -> AgentServiceRequest <$> smpP <*> smpP <*> (unTail <$> smpP)
+      'P' -> AgentServiceResponse . unTail <$> smpP
+      'J' -> AgentRejection . unTail <$> smpP
       _ -> fail "bad AgentMessage"
 
 -- internal type for storing message type in the database
@@ -910,7 +966,11 @@ data AgentMessageType
   | AM_QKEY_
   | AM_QUSE_
   | AM_QTEST_
+  | AM_QEND_
   | AM_EREADY_
+  | AM_SRV_REQ
+  | AM_SRV_RESP
+  | AM_RJCT
   deriving (Eq, Show)
 
 instance Encoding AgentMessageType where
@@ -926,7 +986,11 @@ instance Encoding AgentMessageType where
     AM_QKEY_ -> "QK"
     AM_QUSE_ -> "QU"
     AM_QTEST_ -> "QT"
+    AM_QEND_ -> "QE"
     AM_EREADY_ -> "E"
+    AM_SRV_REQ -> "A"
+    AM_SRV_RESP -> "P"
+    AM_RJCT -> "J"
   smpP =
     A.anyChar >>= \case
       'C' -> pure AM_CONN_INFO
@@ -942,8 +1006,12 @@ instance Encoding AgentMessageType where
           'K' -> pure AM_QKEY_
           'U' -> pure AM_QUSE_
           'T' -> pure AM_QTEST_
+          'E' -> pure AM_QEND_
           _ -> fail "bad AgentMessageType"
       'E' -> pure AM_EREADY_
+      'A' -> pure AM_SRV_REQ
+      'P' -> pure AM_SRV_RESP
+      'J' -> pure AM_RJCT
       _ -> fail "bad AgentMessageType"
 
 agentMessageType :: AgentMessage -> AgentMessageType
@@ -952,6 +1020,9 @@ agentMessageType = \case
   AgentConnInfoReply {} -> AM_CONN_INFO_REPLY
   AgentRatchetInfo _ -> AM_RATCHET_INFO
   AgentMessage _ aMsg -> aMessageType aMsg
+  AgentServiceRequest {} -> AM_SRV_REQ
+  AgentServiceResponse {} -> AM_SRV_RESP
+  AgentRejection {} -> AM_RJCT
 
 data APrivHeader = APrivHeader
   { -- | sequential ID assigned by the sending agent
@@ -975,6 +1046,7 @@ data AMsgType
   | QKEY_
   | QUSE_
   | QTEST_
+  | QEND_
   | EREADY_
   deriving (Eq)
 
@@ -988,6 +1060,7 @@ instance Encoding AMsgType where
     QKEY_ -> "QK"
     QUSE_ -> "QU"
     QTEST_ -> "QT"
+    QEND_ -> "QE"
     EREADY_ -> "E"
   smpP =
     A.anyChar >>= \case
@@ -1001,6 +1074,7 @@ instance Encoding AMsgType where
           'K' -> pure QKEY_
           'U' -> pure QUSE_
           'T' -> pure QTEST_
+          'E' -> pure QEND_
           _ -> fail "bad AMsgType"
       'E' -> pure EREADY_
       _ -> fail "bad AMsgType"
@@ -1025,6 +1099,8 @@ data AMessage
     QUSE (NonEmpty (SndQAddr, Bool))
   | -- sent by the sender to test new queues and to complete switching
     QTEST (NonEmpty SndQAddr)
+  | -- sent by the sender to remove queues from the connection (fast rotation, v8)
+    QEND (NonEmpty SndQAddr)
   | -- ratchet re-synchronization is complete, with last decrypted sender message id (recipient's `last_external_snd_msg_id`)
     EREADY AgentMsgId
   deriving (Show)
@@ -1043,6 +1119,7 @@ aMessageType = \case
   QKEY _ -> AM_QKEY_
   QUSE _ -> AM_QUSE_
   QTEST _ -> AM_QTEST_
+  QEND _ -> AM_QEND_
   EREADY _ -> AM_EREADY_
 
 -- | this type is used to send as part of the protocol between different clients
@@ -1095,6 +1172,7 @@ instance Encoding AMessage where
     QKEY qs -> smpEncode (QKEY_, qs)
     QUSE qs -> smpEncode (QUSE_, qs)
     QTEST qs -> smpEncode (QTEST_, qs)
+    QEND qs -> smpEncode (QEND_, qs)
     EREADY lastDecryptedMsgId -> smpEncode (EREADY_, lastDecryptedMsgId)
   smpP =
     smpP
@@ -1107,6 +1185,7 @@ instance Encoding AMessage where
         QKEY_ -> QKEY <$> smpP
         QUSE_ -> QUSE <$> smpP
         QTEST_ -> QTEST <$> smpP
+        QEND_ -> QEND <$> smpP
         EREADY_ -> EREADY <$> smpP
 
 instance ToField AMessage where toField = toField . Binary . smpEncode
@@ -1122,11 +1201,13 @@ instance Encoding AMessageReceipt where
 
 instance ConnectionModeI m => StrEncoding (ConnectionRequestUri m) where
   strEncode = \case
-    CRInvitationUri crData e2eParams -> crEncode "invitation" crData (Just e2eParams)
-    CRContactUri crData -> crEncode "contact" crData Nothing
+    CRInvitationUri crData e2eParams -> crEncode "invitation" crData (Just e2eParams, Nothing)
+    CRContactUri crData rks -> crEncode "contact" crData $ case rks of
+      Just (ratchetKeyId, e2eRcvParams) -> (Just e2eRcvParams, Just ratchetKeyId)
+      Nothing -> (Nothing, Nothing)
     where
-      crEncode :: ByteString -> ConnReqUriData -> Maybe (RcvE2ERatchetParamsUri 'C.X448) -> ByteString
-      crEncode crMode ConnReqUriData {crScheme, crAgentVRange, crSmpQueues, crClientData} e2eParams =
+      crEncode :: ByteString -> ConnReqUriData -> (Maybe (RcvE2ERatchetParamsUri 'C.X448), Maybe RatchetKeyId) -> ByteString
+      crEncode crMode ConnReqUriData {crScheme, crAgentVRange, crSmpQueues, crClientData} (e2eParams, rk) =
         strEncode crScheme <> "/" <> crMode <> "#/?" <> queryStr
         where
           queryStr =
@@ -1134,23 +1215,24 @@ instance ConnectionModeI m => StrEncoding (ConnectionRequestUri m) where
               -- semicolon is used to separate SMP queues because comma is used to separate server address hostnames
               [("v", strEncode crAgentVRange), ("smp", B.intercalate ";" $ map strEncode $ L.toList crSmpQueues)]
                 <> maybe [] (\e2e -> [("e2e", strEncode e2e)]) e2eParams
+                <> maybe [] (\k -> [("rk", strEncode k)]) rk
                 <> maybe [] (\cd -> [("data", encodeUtf8 cd)]) crClientData
   strP = connReqUriP' (Just SSSimplex)
 
-instance ConnectionModeI m => Encoding (ConnectionRequestUri m) where
+instance ConnectionModeI m => Encoding (BinaryConnectionRequestUri m) where
   smpEncode = \case
-    CRInvitationUri crData e2eParams -> smpEncode (CMInvitation, crData, e2eParams)
-    CRContactUri crData -> smpEncode (CMContact, crData)
-  smpP = (\(ACR _ cr) -> checkConnMode cr) <$?> smpP
+    BCRInvitationUri crData e2eParams -> smpEncode (CMInvitation, crData, e2eParams)
+    BCRContactUri crData -> smpEncode (CMContact, crData)
+  smpP = (\(ABCR _ cr) -> checkConnMode cr) <$?> smpP
   {-# INLINE smpP #-}
 
-instance Encoding AConnectionRequestUri where
-  smpEncode (ACR _ cr) = smpEncode cr
+instance Encoding ABinaryConnectionRequestUri where
+  smpEncode (ABCR _ cr) = smpEncode cr
   {-# INLINE smpEncode #-}
   smpP =
     smpP >>= \case
-      CMInvitation -> ACR SCMInvitation <$> (CRInvitationUri <$> smpP <*> smpP)
-      CMContact -> ACR SCMContact . CRContactUri <$> smpP
+      CMInvitation -> ABCR SCMInvitation <$> (BCRInvitationUri <$> smpP <*> smpP)
+      CMContact -> ABCR SCMContact . BCRContactUri <$> smpP
 
 instance Encoding ConnReqUriData where
   smpEncode ConnReqUriData {crAgentVRange, crSmpQueues, crClientData} =
@@ -1193,7 +1275,10 @@ connReqUriP overrideScheme = do
       pure . ACR SCMInvitation $ CRInvitationUri crData crE2eParams
     -- contact links are adjusted to the minimum version supported by the agent
     -- to preserve compatibility with the old links published online
-    CMContact -> pure . ACR SCMContact $ CRContactUri crData {crAgentVRange = adjustAgentVRange aVRange}
+    CMContact -> do
+      e2e_ <- queryParam_ "e2e" query
+      rk_ <- queryParam_ "rk" query
+      pure . ACR SCMContact $ CRContactUri crData {crAgentVRange = adjustAgentVRange aVRange} ((,) <$> rk_ <*> e2e_)
   where
     crModeP = "invitation" $> CMInvitation <|> "contact" $> CMContact
     -- semicolon is used to separate SMP queues because comma is used to separate server address hostnames
@@ -1319,6 +1404,7 @@ sameQueue addr q = sameQAddress addr (qAddress q)
 
 data SMPQueueInfo = SMPQueueInfo {clientVersion :: VersionSMPC, queueAddress :: SMPQueueAddress}
   deriving (Eq, Show)
+  deriving (ToJSON, FromJSON) via (StrJSON "SMPQueueInfo" SMPQueueInfo)
 
 instance Encoding SMPQueueInfo where
   smpEncode (SMPQueueInfo clientVersion SMPQueueAddress {smpServer, senderId, dhPublicKey, queueMode})
@@ -1424,6 +1510,10 @@ instance StrEncoding SMPQueueUri where
               _ -> Nothing
         pure (vr, maybe [] thList_ hs_, dhKey, queueMode)
 
+instance StrEncoding SMPQueueInfo where
+  strEncode (SMPQueueInfo v addr) = strEncode (SMPQueueUri (versionToRange v) addr)
+  strP = (\(SMPQueueUri vr addr) -> SMPQueueInfo (maxVersion vr) addr) <$> strP
+
 instance Encoding SMPQueueUri where
   smpEncode (SMPQueueUri clientVRange@(VersionRange minV maxV) SMPQueueAddress {smpServer, senderId, dhPublicKey, queueMode})
     -- The condition is for minVersion as earlier clients won't be able to support it.
@@ -1443,16 +1533,30 @@ instance Encoding SMPQueueUri where
 queueModeP :: Parser (Maybe QueueMode)
 queueModeP = Just <$> smpP <|> optional ((\case True -> QMMessaging; _ -> QMContact) <$> smpP)
 
+data BinaryConnectionRequestUri (m :: ConnectionMode) where
+  BCRInvitationUri :: ConnReqUriData -> RcvE2ERatchetParamsUri 'C.X448 -> BinaryConnectionRequestUri CMInvitation
+  BCRContactUri :: ConnReqUriData -> BinaryConnectionRequestUri CMContact
+
+deriving instance Eq (BinaryConnectionRequestUri m)
+
+deriving instance Show (BinaryConnectionRequestUri m)
+
+data ABinaryConnectionRequestUri = forall m. ConnectionModeI m => ABCR (SConnectionMode m) (BinaryConnectionRequestUri m)
+
 data ConnectionRequestUri (m :: ConnectionMode) where
   CRInvitationUri :: ConnReqUriData -> RcvE2ERatchetParamsUri 'C.X448 -> ConnectionRequestUri CMInvitation
-  -- contact connection request does NOT contain E2E encryption parameters for double ratchet -
-  -- they are passed in AgentInvitation message
-  CRContactUri :: ConnReqUriData -> ConnectionRequestUri CMContact
+  -- optional contact address DR keys for double ratchet e2e from message 1
+  CRContactUri :: ConnReqUriData -> Maybe AddressRatchetKeys -> ConnectionRequestUri CMContact
 
 simplexConnReqUri :: ConnectionRequestUri m -> ConnectionRequestUri m
 simplexConnReqUri = \case
   CRInvitationUri crData e2eParams -> CRInvitationUri crData {crScheme = SSSimplex} e2eParams
-  CRContactUri crData -> CRContactUri crData {crScheme = SSSimplex}
+  CRContactUri crData rk -> CRContactUri crData {crScheme = SSSimplex} rk
+
+binaryConnReq :: ConnectionRequestUri m -> BinaryConnectionRequestUri m
+binaryConnReq = \case
+  CRInvitationUri crData e2eParams -> BCRInvitationUri crData e2eParams
+  CRContactUri crData _ -> BCRContactUri crData
 
 deriving instance Eq (ConnectionRequestUri m)
 
@@ -1510,9 +1614,12 @@ data PreparedLinkParams = PreparedLinkParams
     -- | smpEncode of FixedLinkData (includes linkEntityId)
     plpSignedFixedData :: ByteString,
     -- | Server with basic auth (not stored in link)
-    plpSrvWithAuth :: SMPServerWithAuth
+    plpSrvWithAuth :: SMPServerWithAuth,
+    -- | Initial PQ keys
+    plpInitKeys :: InitialKeys,
+    -- | Contact address double ratchet keys
+    plpAddressKeys :: Maybe (RatchetKeyId, RcvE2EPrivRatchetParams 'C.X448)
   }
-  deriving (Show)
 
 instance ConnectionModeI c => ToField (ConnectionLink c) where toField = toField . Binary . strEncode
 
@@ -1682,6 +1789,10 @@ ctTypeChar = \case
   CCTRelay -> 'R'
 {-# INLINE ctTypeChar #-}
 
+instance StrEncoding ContactConnType where
+  strEncode = B.singleton . ctTypeChar
+  strP = A.anyChar >>= ctTypeP
+
 -- the servers passed to this function should be all preset servers, not servers configured by the user.
 shortenShortLink :: NonEmpty SMPServer -> ConnShortLink m -> ConnShortLink m
 shortenShortLink presetSrvs = \case
@@ -1720,15 +1831,26 @@ findPresetServer ProtocolServer {host = h :| _} = find (\ProtocolServer {host =
 {-# INLINE findPresetServer #-}
 
 sameConnReqContact :: ConnectionRequestUri 'CMContact -> ConnectionRequestUri 'CMContact -> Bool
-sameConnReqContact (CRContactUri ConnReqUriData {crSmpQueues = qs}) (CRContactUri ConnReqUriData {crSmpQueues = qs'}) =
+sameConnReqContact (CRContactUri ConnReqUriData {crSmpQueues = qs} _) (CRContactUri ConnReqUriData {crSmpQueues = qs'} _) =
   L.length qs == L.length qs' && all same (L.zip qs qs')
   where
     same (q, q') = sameQAddress (qAddress q) (qAddress q')
 
+sameConnShortLink :: AConnShortLink -> AConnShortLink -> Bool
+sameConnShortLink (ACSL m sl) (ACSL m' sl') = case testEquality m m' of
+  Just Refl -> case sl of
+    CSLContact {} -> sameShortLinkContact sl sl'
+    CSLInvitation {} -> sameShortLinkInv sl sl'
+  Nothing -> False
+
 sameShortLinkContact :: ConnShortLink 'CMContact -> ConnShortLink 'CMContact -> Bool
 sameShortLinkContact (CSLContact _ ct srv k) (CSLContact _ ct' srv' k') =
   ct == ct' && sameSrvAddr srv srv' && k == k'
 
+sameShortLinkInv :: ConnShortLink 'CMInvitation -> ConnShortLink 'CMInvitation -> Bool
+sameShortLinkInv (CSLInvitation _ srv lnkId k) (CSLInvitation _ srv' lnkId' k') =
+  sameSrvAddr srv srv' && lnkId == lnkId' && k == k'
+
 checkConnMode :: forall t m m'. (ConnectionModeI m, ConnectionModeI m') => t m' -> Either String (t m)
 checkConnMode c = case testEquality (sConnectionMode @m) (sConnectionMode @m') of
   Just Refl -> Right c
@@ -1748,7 +1870,7 @@ type CRClientData = Text
 data FixedLinkData c = FixedLinkData
   { agentVRange :: VersionRangeSMPA,
     rootKey :: C.PublicKeyEd25519,
-    linkConnReq :: ConnectionRequestUri c,
+    linkConnReq :: BinaryConnectionRequestUri c,
     linkEntityId :: Maybe ByteString
   }
   deriving (Eq, Show)
@@ -1761,6 +1883,31 @@ deriving instance Eq (ConnLinkData c)
 
 deriving instance Show (ConnLinkData c)
 
+newtype RatchetKeyId = RatchetKeyId ByteString
+  deriving (Eq, Show)
+  deriving newtype (Encoding, StrEncoding)
+
+-- | double ratchet keys in contact address
+type AddressRatchetKeys = (RatchetKeyId, RcvE2ERatchetParamsUri 'C.X448)
+
+-- | Whether to rotate double ratchet keys in contact address
+type NewRatchetKeys = Bool
+
+-- | stored invitation with double ratchet keys
+data DRInvitation = DRInvitation
+  { ratchetState :: RatchetX448,
+    replyQueue :: SMPQueueInfo,
+    agentVersion :: VersionSMPA,
+    pqSupport :: PQSupport
+  }
+  deriving (Show)
+
+data JoinRequest
+  = JRConnReq {enableNtfs :: Bool, joinConnReq :: AConnectionRequestUri, joinPQSupport :: PQSupport}
+  | JRServiceReq {contactReq :: ConnectionRequestUri 'CMContact, joinPQSupport :: PQSupport, requestKey :: Maybe (C.StoredPrivateKey C.Ed25519)}
+  | JRInvitationDR DRInvitation
+  deriving (Show)
+
 data UserContactData = UserContactData
   { -- direct connection via connReq in fixed data is allowed.
     direct :: Bool,
@@ -1768,7 +1915,8 @@ data UserContactData = UserContactData
     owners :: [OwnerAuth],
     -- alternative addresses of chat relays that receive requests for this contact address.
     relays :: [ConnShortLink 'CMContact],
-    userData :: UserLinkData
+    userData :: UserLinkData,
+    ratchetKeys :: Maybe AddressRatchetKeys
   }
   deriving (Eq, Show)
 
@@ -1846,10 +1994,12 @@ validateLinkOwners rootKey = go []
 
 instance ConnectionModeI c => Encoding (FixedLinkData c) where
   smpEncode FixedLinkData {agentVRange, rootKey, linkConnReq, linkEntityId} =
+    -- TODO this encoding is not extensible, replace with smpEncode (fromMaybe "" linkEntityId) - safe to do it in 2027
     smpEncode (agentVRange, rootKey, linkConnReq) <> maybe "" smpEncode linkEntityId
   smpP = do
     (agentVRange, rootKey, linkConnReq) <- smpP
-    linkEntityId <- optional smpP <* A.takeByteString -- ignoring tail for forward compatibility with the future link data encoding
+    linkEntityId <- ((\s -> if B.null s then Nothing else Just s) =<<) <$> optional smpP
+    _ <- A.takeByteString -- ignoring tail for forward compatibility with the future link data encoding (added in January 2026)
     pure FixedLinkData {agentVRange, rootKey, linkConnReq, linkEntityId}
 
 instance ConnectionModeI c => Encoding (ConnLinkData c) where
@@ -1896,14 +2046,13 @@ instance ConnectionModeI c => StrEncoding (UserConnLinkData c) where
   {-# INLINE strP #-}
 
 instance Encoding UserContactData where
-  smpEncode UserContactData {direct, owners, relays, userData} =
-    B.concat [smpEncode direct, smpEncodeList owners, smpEncodeList relays, smpEncode userData]
+  smpEncode UserContactData {direct, owners, relays, userData, ratchetKeys} =
+    smpEncode (direct, EncList owners, EncList relays, userData, ratchetKeys)
   smpP = do
-    direct <- smpP
-    owners <- smpListP
-    relays <- smpListP
-    userData <- smpP <* A.takeByteString -- ignoring tail for forward compatibility with the future link data encoding
-    pure UserContactData {direct, owners, relays, userData}
+    (direct, EncList owners, EncList relays, userData) <- smpP
+    ratchetKeys <- smpP <|> pure Nothing
+    _ <- A.takeByteString -- ignoring tail for forward compatibility with the future link data encoding
+    pure UserContactData {direct, owners, relays, userData, ratchetKeys}
 
 instance Encoding UserLinkData where
   smpEncode (UserLinkData s) = if B.length s <= 254 then smpEncode s else smpEncode ('\255', Large s)
@@ -1991,6 +2140,9 @@ data AgentErrorType
     XFTP {serverAddress :: String, xftpErr :: XFTPErrorType}
   | -- | XFTP agent errors
     FILE {fileErr :: FileErrorType}
+  | -- | no name-resolving servers configured for the user (agent-origin).
+    -- Server-origin name errors arrive forwarded as SMP _ (NAME ...) instead.
+    NO_NAME_SERVERS
   | -- | SMP proxy errors
     PROXY {proxyServer :: String, relayServer :: String, proxyErr :: ProxyClientError}
   | -- | XRCP protocol errors forwarded to agent clients
@@ -2048,7 +2200,7 @@ data ConnectionErrorType
 -- | Errors of another SMP agent.
 data SMPAgentError
   = -- | client or agent message that failed to parse
-    A_MESSAGE
+    A_MESSAGE {messageErr :: String}
   | -- | prohibited SMP/agent message
     A_PROHIBITED {prohibitedErr :: String}
   | -- | incompatible version of SMP client, agent or encryption protocols
@@ -2063,8 +2215,17 @@ data SMPAgentError
     A_DUPLICATE {droppedMsg_ :: Maybe DroppedMsg}
   | -- | error in the message to add/delete/etc queue in connection
     A_QUEUE {queueErr :: String}
+  | A_SERVICE {serviceError :: AgentServiceError}
   deriving (Eq, Show, Exception)
 
+data AgentServiceError
+  = ASERejected {rejectReason :: Text}
+  | ASETimeout
+  | ASENoPendingRequest
+  | ASENotDRAddress
+  | ASEBadSignature
+  deriving (Eq, Show)
+
 data AgentCryptoError
   = -- | AES decryption error
     DECRYPT_AES
@@ -2089,6 +2250,19 @@ cryptoErrToSyncState = \case
   RATCHET_SKIPPED _ -> RSRequired
   RATCHET_SYNC -> RSRequired
 
+$(J.deriveJSON defaultJSON ''DRInvitation)
+
+-- JRConnReq is identical to JOIN before DR support for old/new client compatibility
+instance StrEncoding JoinRequest where
+  strEncode = \case
+    JRConnReq ntfs cReq pqSup -> strEncode (ntfs, cReq, pqSup)
+    JRServiceReq cReq pqSup signKey -> strEncode ('S', cReq, pqSup, signKey)
+    JRInvitationDR dr -> serializeBinary $ LB.toStrict (J'.encode dr)
+  strP =
+    (A.char 'S' *> (JRServiceReq <$> _strP <*> _strP <*> _strP))
+      <|> (JRConnReq <$> strP <*> _strP <*> (_strP <|> pure PQSupportOff))
+      <|> (JRInvitationDR <$> (J'.eitherDecodeStrict' <$?> (A.take =<< (A.decimal <* "\n"))))
+
 -- | SMP agent command and response parser for commands stored in db (fully parses binary bodies)
 dbCommandP :: Parser ACommand
 dbCommandP = commandP $ A.take =<< (A.decimal <* "\n")
@@ -2119,10 +2293,11 @@ commandP :: Parser ByteString -> Parser ACommand
 commandP binaryP =
   strP
     >>= \case
-      NEW_ -> s (NEW <$> strP_ <*> strP_ <*> pqIKP <*> (strP <|> pure SMP.SMSubscribe))
+      -- useDR is a trailing field defaulting to False, so NEW persisted before it was added still parses
+      NEW_ -> s (NEW <$> strP_ <*> strP_ <*> pqIKP <*> (strP <|> pure SMP.SMSubscribe) <*> (_strP <|> pure False))
       LSET_ -> s (LSET <$> strP <*> optional (A.space *> strP))
       LGET_ -> s (LGET <$> strP)
-      JOIN_ -> s (JOIN <$> strP_ <*> strP_ <*> pqSupP <*> (strP_ <|> pure SMP.SMSubscribe) <*> binaryP)
+      JOIN_ -> s (JOIN <$> strP_ <*> (strP_ <|> pure SMP.SMSubscribe) <*> binaryP)
       LET_ -> s (LET <$> A.takeTill (== ' ') <* A.space <*> binaryP)
       ACK_ -> s (ACK <$> A.decimal <*> optional (A.space *> binaryP))
       SWCH_ -> pure SWCH
@@ -2132,16 +2307,14 @@ commandP binaryP =
     s p = A.space *> p
     pqIKP :: Parser InitialKeys
     pqIKP = strP_ <|> pure (IKLinkPQ PQSupportOff)
-    pqSupP :: Parser PQSupport
-    pqSupP = strP_ <|> pure PQSupportOff
 
 -- | Serialize SMP agent command.
 serializeCommand :: ACommand -> ByteString
 serializeCommand = \case
-  NEW ntfs cMode pqIK subMode -> s (NEW_, ntfs, cMode, pqIK, subMode)
+  NEW ntfs cMode pqIK subMode useDR -> s (NEW_, ntfs, cMode, pqIK, subMode, useDR)
   LSET uld cd_ -> s (LSET_, uld) <> maybe "" (B.cons ' ' . s) cd_
   LGET sl -> s (LGET_, sl)
-  JOIN ntfs cReq pqSup subMode cInfo -> s (JOIN_, ntfs, cReq, pqSup, subMode, Str $ serializeBinary cInfo)
+  JOIN joinReq subMode cInfo -> s (JOIN_, joinReq, subMode, Str $ serializeBinary cInfo)
   LET confId cInfo -> B.unwords [s LET_, confId, serializeBinary cInfo]
   ACK mId rcptInfo_ -> s (ACK_, mId) <> maybe "" (B.cons ' ' . serializeBinary) rcptInfo_
   SWCH -> s SWCH_
@@ -2173,6 +2346,8 @@ $(J.deriveJSON (sumTypeJSON id) ''ConnectionErrorType)
 
 $(J.deriveJSON (sumTypeJSON id) ''AgentCryptoError)
 
+$(J.deriveJSON (sumTypeJSON $ dropPrefix "ASE") ''AgentServiceError)
+
 $(J.deriveJSON defaultJSON ''DroppedMsg)
 
 $(J.deriveJSON (sumTypeJSON id) ''SMPAgentError)
@@ -2201,3 +2376,4 @@ instance FromJSON ACreatedConnLink where
 instance ToJSON ACreatedConnLink where
   toEncoding (ACCL _ ccLink) = toEncoding ccLink
   toJSON (ACCL _ ccLink) = toJSON ccLink
+

src/Simplex/Messaging/Agent/Store.hs

@@ -45,6 +45,8 @@ module Simplex.Messaging.Agent.Store
     AcceptedConfirmation (..),
     NewInvitation (..),
     Invitation (..),
+    ContactRequest (..),
+    DRInvitation (..),
     PrevExternalSndId,
     PrevRcvMsgHash,
     PrevSndMsgHash,
@@ -205,12 +207,13 @@ rcvSMPQueueAddress :: RcvQueue -> SMPQueueAddress
 rcvSMPQueueAddress RcvQueue {server, sndId, e2ePrivKey, queueMode} =
   SMPQueueAddress server sndId (C.publicKey e2ePrivKey) queueMode
 
-canAbortRcvSwitch :: RcvQueue -> Bool
-canAbortRcvSwitch = maybe False canAbort . rcvSwchStatus
+canAbortRcvSwitch :: ConnData -> RcvQueue -> Bool
+canAbortRcvSwitch ConnData {connAgentVersion} = maybe False canAbort . rcvSwchStatus
   where
     canAbort = \case
       RSSwitchStarted -> True
-      RSSendingQADD -> True
+      -- at agent version 8 and above the peer always chooses fast rotation, so a sent QADD is committed
+      RSSendingQADD -> connAgentVersion < rpcAddressSMPAgentVersion
       -- if switch is in RSSendingQUSE, a race condition with sender deleting the original queue is possible
       RSSendingQUSE -> False
       -- if switch is in RSReceivedMessage status, aborting switch (deleting new queue)
@@ -463,7 +466,9 @@ data ConnData = ConnData
     lastExternalSndId :: PrevExternalSndId,
     deleted :: Bool,
     ratchetSyncState :: RatchetSyncState,
-    pqSupport :: PQSupport
+    pqSupport :: PQSupport,
+    -- client side: set on the requester's connection for a service request; Nothing otherwise. The time the client stops waiting for the response (created + serviceRequestTimeout or per-call override).
+    serviceRequestExpiresAt :: Maybe UTCTime
   }
   deriving (Eq, Show)
 
@@ -471,8 +476,8 @@ type NoticeId = Int64
 
 -- this function should be mirrored in the clients
 ratchetSyncAllowed :: ConnData -> Bool
-ratchetSyncAllowed ConnData {ratchetSyncState, connAgentVersion} =
-  connAgentVersion >= ratchetSyncSMPAgentVersion && (ratchetSyncState `elem` ([RSAllowed, RSRequired] :: [RatchetSyncState]))
+ratchetSyncAllowed ConnData {ratchetSyncState} =
+  ratchetSyncState `elem` ([RSAllowed, RSRequired] :: [RatchetSyncState])
 
 -- this function should be mirrored in the clients
 ratchetSyncSendProhibited :: ConnData -> Bool
@@ -534,7 +539,9 @@ data InternalCommand
   | ICDeleteConn
   | ICDeleteRcvQueue SMP.RecipientId
   | ICQSecure SMP.RecipientId SMP.SndPublicAuthKey
+  | ICQSndSecure SMP.SenderId
   | ICQDelete SMP.RecipientId
+  | ICReplyDel
 
 data InternalCommandTag
   = ICAck_
@@ -544,7 +551,9 @@ data InternalCommandTag
   | ICDeleteConn_
   | ICDeleteRcvQueue_
   | ICQSecure_
+  | ICQSndSecure_
   | ICQDelete_
+  | ICReplyDel_
   deriving (Show)
 
 instance StrEncoding InternalCommand where
@@ -556,7 +565,9 @@ instance StrEncoding InternalCommand where
     ICDeleteConn -> strEncode ICDeleteConn_
     ICDeleteRcvQueue rId -> strEncode (ICDeleteRcvQueue_, rId)
     ICQSecure rId senderKey -> strEncode (ICQSecure_, rId, senderKey)
+    ICQSndSecure sId -> strEncode (ICQSndSecure_, sId)
     ICQDelete rId -> strEncode (ICQDelete_, rId)
+    ICReplyDel -> strEncode ICReplyDel_
   strP =
     strP >>= \case
       ICAck_ -> ICAck <$> _strP <*> _strP
@@ -566,7 +577,9 @@ instance StrEncoding InternalCommand where
       ICDeleteConn_ -> pure ICDeleteConn
       ICDeleteRcvQueue_ -> ICDeleteRcvQueue <$> _strP
       ICQSecure_ -> ICQSecure <$> _strP <*> _strP
+      ICQSndSecure_ -> ICQSndSecure <$> _strP
       ICQDelete_ -> ICQDelete <$> _strP
+      ICReplyDel_ -> pure ICReplyDel
 
 instance StrEncoding InternalCommandTag where
   strEncode = \case
@@ -577,7 +590,9 @@ instance StrEncoding InternalCommandTag where
     ICDeleteConn_ -> "DELETE_CONN"
     ICDeleteRcvQueue_ -> "DELETE_RCV_QUEUE"
     ICQSecure_ -> "QSECURE"
+    ICQSndSecure_ -> "QSND_SECURE"
     ICQDelete_ -> "QDELETE"
+    ICReplyDel_ -> "REPLY_DEL"
   strP =
     A.takeTill (== ' ') >>= \case
       "ACK" -> pure ICAck_
@@ -587,7 +602,9 @@ instance StrEncoding InternalCommandTag where
       "DELETE_CONN" -> pure ICDeleteConn_
       "DELETE_RCV_QUEUE" -> pure ICDeleteRcvQueue_
       "QSECURE" -> pure ICQSecure_
+      "QSND_SECURE" -> pure ICQSndSecure_
       "QDELETE" -> pure ICQDelete_
+      "REPLY_DEL" -> pure ICReplyDel_
       _ -> fail "bad InternalCommandTag"
 
 agentCommandTag :: AgentCommand -> AgentCommandTag
@@ -604,7 +621,9 @@ internalCmdTag = \case
   ICDeleteConn -> ICDeleteConn_
   ICDeleteRcvQueue {} -> ICDeleteRcvQueue_
   ICQSecure {} -> ICQSecure_
+  ICQSndSecure {} -> ICQSndSecure_
   ICQDelete _ -> ICQDelete_
+  ICReplyDel -> ICReplyDel_
 
 -- * Confirmation types
 
@@ -626,19 +645,28 @@ data AcceptedConfirmation = AcceptedConfirmation
 
 data NewInvitation = NewInvitation
   { contactConnId :: ConnId,
-    connReq :: ConnectionRequestUri 'CMInvitation,
-    recipientConnInfo :: ConnInfo
+    connReq :: ContactRequest,
+    recipientConnInfo :: ConnInfo,
+    -- service side: the received request is a service request (SREQ) not a contact request (REQ)
+    serviceRequest :: Bool
   }
 
 data Invitation = Invitation
   { invitationId :: InvitationId,
     contactConnId_ :: Maybe ConnId,
-    connReq :: ConnectionRequestUri 'CMInvitation,
+    connReq :: ContactRequest,
     recipientConnInfo :: ConnInfo,
     ownConnInfo :: Maybe ConnInfo,
-    accepted :: Bool
+    accepted :: Bool,
+    -- service side: the received request is a service request (SREQ) not a contact request (REQ)
+    serviceRequest :: Bool,
+    createdAt :: UTCTime
   }
 
+data ContactRequest
+  = CRInvitation (ConnectionRequestUri 'CMInvitation)
+  | CRInvitationDR DRInvitation
+
 -- * Message integrity validation types
 
 -- | Corresponds to `last_external_snd_msg_id` in `connections` table

src/Simplex/Messaging/Agent/Store/AgentStore.hs

@@ -73,6 +73,8 @@ module Simplex.Messaging.Agent.Store.AgentStore
     setConnPQSupport,
     updateNewConnJoin,
     getDeletedConnIds,
+    getExpiredServiceConns,
+    deleteExpiredServiceRequests,
     getDeletedWaitingDeliveryConnIds,
     setConnRatchetSync,
     addProcessedRatchetKeyHash,
@@ -129,6 +131,8 @@ module Simplex.Messaging.Agent.Store.AgentStore
     createSndMsg,
     updateSndMsgHash,
     createSndMsgDelivery,
+    copyPendingSndDeliveries,
+    countSndQueueDeliveries,
     getSndMsgViaRcpt,
     updateSndMsgRcpt,
     getPendingQueueMsg,
@@ -152,6 +156,10 @@ module Simplex.Messaging.Agent.Store.AgentStore
     createRatchetX3dhKeys,
     getRatchetX3dhKeys,
     setRatchetX3dhKeys,
+    createAddressRatchetKeys,
+    getCurrentAddressRatchetKeys,
+    getAddressRatchetKeys,
+    deleteOldAddressRatchetKeys,
     createSndRatchet,
     getSndRatchet,
     createRatchet,
@@ -278,9 +286,11 @@ import Control.Monad.IO.Class
 import Control.Monad.Trans.Except
 import Crypto.Random (ChaChaDRG)
 import Data.Bifunctor (first)
+import qualified Data.Aeson as J
 import Data.ByteString (ByteString)
 import qualified Data.ByteString.Base64.URL as U
 import qualified Data.ByteString.Char8 as B
+import qualified Data.ByteString.Lazy as LB
 import Data.Functor (($>))
 import Data.Int (Int64)
 import Data.List (foldl', sortBy)
@@ -558,14 +568,16 @@ createSndConn db gVar cData q@SndQueue {server} =
       insertSndQueue_ db connId q serverKeyHash_
 
 createConnRecord :: DB.Connection -> ConnId -> ConnData -> SConnectionMode c -> IO ()
-createConnRecord db connId ConnData {userId, connAgentVersion, enableNtfs, pqSupport} cMode =
+createConnRecord db connId ConnData {userId, connAgentVersion, enableNtfs, pqSupport, serviceRequestExpiresAt} cMode = do
+  createdAt <- getCurrentTime
   DB.execute
     db
     [sql|
       INSERT INTO connections
-        (user_id, conn_id, conn_mode, smp_agent_version, enable_ntfs, pq_support, duplex_handshake) VALUES (?,?,?,?,?,?,?)
+        (user_id, conn_id, conn_mode, smp_agent_version, enable_ntfs, pq_support, service_request_expires_at, duplex_handshake, created_at)
+        VALUES (?,?,?,?,?,?,?,?,?)
     |]
-    (userId, connId, cMode, connAgentVersion, BI enableNtfs, pqSupport, BI True)
+    (userId, connId, cMode, connAgentVersion, BI enableNtfs, pqSupport, serviceRequestExpiresAt, BI True, createdAt)
 
 deleteConnRecord :: DB.Connection -> ConnId -> IO ()
 deleteConnRecord db connId = DB.execute db "DELETE FROM connections WHERE conn_id = ?" (Only connId)
@@ -868,15 +880,15 @@ removeConfirmations db connId =
     (Only connId)
 
 createInvitation :: DB.Connection -> TVar ChaChaDRG -> NewInvitation -> IO (Either StoreError InvitationId)
-createInvitation db gVar NewInvitation {contactConnId, connReq, recipientConnInfo} =
+createInvitation db gVar NewInvitation {contactConnId, connReq, recipientConnInfo, serviceRequest} =
   createWithRandomId db gVar $ \invitationId ->
     DB.execute
       db
       [sql|
         INSERT INTO conn_invitations
-        (invitation_id, contact_conn_id, cr_invitation, recipient_conn_info, accepted) VALUES (?, ?, ?, ?, 0);
+        (invitation_id, contact_conn_id, cr_invitation, recipient_conn_info, accepted, service_request) VALUES (?, ?, ?, ?, 0, ?);
       |]
-      (Binary invitationId, contactConnId, connReq, Binary recipientConnInfo)
+      (Binary invitationId, contactConnId, connReq, Binary recipientConnInfo, BI serviceRequest)
 
 getInvitation :: DB.Connection -> String -> InvitationId -> IO (Either StoreError Invitation)
 getInvitation db cxt invitationId =
@@ -884,15 +896,15 @@ getInvitation db cxt invitationId =
     DB.query
       db
       [sql|
-        SELECT contact_conn_id, cr_invitation, recipient_conn_info, own_conn_info, accepted
+        SELECT contact_conn_id, cr_invitation, recipient_conn_info, own_conn_info, accepted, service_request, created_at
         FROM conn_invitations
         WHERE invitation_id = ?
           AND accepted = 0
       |]
       (Only (Binary invitationId))
   where
-    invitation (contactConnId_, connReq, recipientConnInfo, ownConnInfo, BI accepted) =
-      Invitation {invitationId, contactConnId_, connReq, recipientConnInfo, ownConnInfo, accepted}
+    invitation (contactConnId_, connReq, recipientConnInfo, ownConnInfo, BI accepted, BI serviceRequest, createdAt) =
+      Invitation {invitationId, contactConnId_, connReq, recipientConnInfo, ownConnInfo, accepted, serviceRequest, createdAt}
 
 acceptInvitation :: DB.Connection -> InvitationId -> ConnInfo -> IO ()
 acceptInvitation db invitationId ownConnInfo =
@@ -1031,6 +1043,24 @@ createSndMsgDelivery :: DB.Connection -> SndQueue -> InternalId -> IO ()
 createSndMsgDelivery db SndQueue {connId, dbQueueId} msgId =
   DB.execute db "INSERT INTO snd_message_deliveries (conn_id, snd_queue_id, internal_id) VALUES (?, ?, ?)" (connId, dbQueueId, msgId)
 
+-- copies every undelivered (failed = 0) delivery from one snd queue to another, for redundant delivery during fast rotation
+copyPendingSndDeliveries :: DB.Connection -> SndQueue -> SndQueue -> IO ()
+copyPendingSndDeliveries db SndQueue {connId, dbQueueId = fromQueueId} SndQueue {dbQueueId = toQueueId} =
+  DB.execute
+    db
+    [sql|
+      INSERT INTO snd_message_deliveries (conn_id, snd_queue_id, internal_id)
+      SELECT conn_id, ?, internal_id
+      FROM snd_message_deliveries
+      WHERE conn_id = ? AND snd_queue_id = ? AND failed = 0
+    |]
+    (toQueueId, connId, fromQueueId)
+
+countSndQueueDeliveries :: DB.Connection -> SndQueue -> IO Int
+countSndQueueDeliveries db SndQueue {connId, dbQueueId} =
+  maybeFirstRow' 0 fromOnly $
+    DB.query db "SELECT count(1) FROM snd_message_deliveries WHERE conn_id = ? AND snd_queue_id = ? AND failed = 0" (connId, dbQueueId)
+
 getSndMsgViaRcpt :: DB.Connection -> ConnId -> InternalSndId -> IO (Either StoreError SndMsg)
 getSndMsgViaRcpt db connId sndMsgId =
   firstRow toSndMsg (SEMsgNotFound "getSndMsgViaRcpt") $
@@ -1359,11 +1389,11 @@ deleteSndMsgsExpired db ttl limit = do
     |]
     (cutoffTs, limit)
 
-createRatchetX3dhKeys :: DB.Connection -> ConnId -> C.PrivateKeyX448 -> C.PrivateKeyX448 -> Maybe CR.RcvPrivRKEMParams -> IO ()
-createRatchetX3dhKeys db connId x3dhPrivKey1 x3dhPrivKey2 pqPrivKem =
+createRatchetX3dhKeys :: DB.Connection -> ConnId -> CR.RcvE2EPrivRatchetParams 'C.X448 -> IO ()
+createRatchetX3dhKeys db connId (x3dhPrivKey1, x3dhPrivKey2, pqPrivKem) =
   DB.execute db "INSERT INTO ratchets (conn_id, x3dh_priv_key_1, x3dh_priv_key_2, pq_priv_kem) VALUES (?, ?, ?, ?)" (connId, x3dhPrivKey1, x3dhPrivKey2, pqPrivKem)
 
-getRatchetX3dhKeys :: DB.Connection -> ConnId -> IO (Either StoreError (C.PrivateKeyX448, C.PrivateKeyX448, Maybe CR.RcvPrivRKEMParams))
+getRatchetX3dhKeys :: DB.Connection -> ConnId -> IO (Either StoreError (CR.RcvE2EPrivRatchetParams 'C.X448))
 getRatchetX3dhKeys db connId =
   firstRow' keys SEX3dhKeysNotFound $
     DB.query db "SELECT x3dh_priv_key_1, x3dh_priv_key_2, pq_priv_kem FROM ratchets WHERE conn_id = ?" (Only connId)
@@ -1373,8 +1403,8 @@ getRatchetX3dhKeys db connId =
       _ -> Left SEX3dhKeysNotFound
 
 -- used to remember new keys when starting ratchet re-synchronization
-setRatchetX3dhKeys :: DB.Connection -> ConnId -> C.PrivateKeyX448 -> C.PrivateKeyX448 -> Maybe CR.RcvPrivRKEMParams -> IO ()
-setRatchetX3dhKeys db connId x3dhPrivKey1 x3dhPrivKey2 pqPrivKem =
+setRatchetX3dhKeys :: DB.Connection -> ConnId -> CR.RcvE2EPrivRatchetParams 'C.X448 -> IO ()
+setRatchetX3dhKeys db connId (x3dhPrivKey1, x3dhPrivKey2, pqPrivKem) =
   DB.execute
     db
     [sql|
@@ -1384,6 +1414,60 @@ setRatchetX3dhKeys db connId x3dhPrivKey1 x3dhPrivKey2 pqPrivKem =
     |]
     (x3dhPrivKey1, x3dhPrivKey2, pqPrivKem, connId)
 
+createAddressRatchetKeys :: DB.Connection -> ConnId -> (RatchetKeyId, CR.RcvE2EPrivRatchetParams 'C.X448) -> IO ()
+createAddressRatchetKeys db connId (ratchetKeyId, (x3dhPrivKey1, x3dhPrivKey2, pqPrivKem)) =
+  DB.execute
+    db
+    [sql|
+      INSERT INTO address_ratchet_keys
+        (conn_id, ratchet_key_id, x3dh_priv_key_1, x3dh_priv_key_2, pq_priv_kem)
+      VALUES (?, ?, ?, ?, ?)
+    |]
+    (connId, ratchetKeyId, x3dhPrivKey1, x3dhPrivKey2, pqPrivKem)
+
+getCurrentAddressRatchetKeys :: DB.Connection -> ConnId -> IO (Either StoreError (RatchetKeyId, CR.RcvE2EPrivRatchetParams 'C.X448))
+getCurrentAddressRatchetKeys db connId =
+  firstRow (\(Only rkId :. pks) -> (rkId, pks)) SEX3dhKeysNotFound $
+    DB.query
+      db
+      [sql|
+        SELECT ratchet_key_id, x3dh_priv_key_1, x3dh_priv_key_2, pq_priv_kem
+        FROM address_ratchet_keys
+        WHERE conn_id = ?
+        ORDER BY address_ratchet_key_id DESC
+        LIMIT 1
+      |]
+      (Only connId)
+
+getAddressRatchetKeys :: DB.Connection -> ConnId -> RatchetKeyId -> IO (Either StoreError (CR.RcvE2EPrivRatchetParams 'C.X448))
+getAddressRatchetKeys db connId ratchetKeyId =
+  firstRow id SEX3dhKeysNotFound $
+    DB.query
+      db
+      [sql|
+        SELECT x3dh_priv_key_1, x3dh_priv_key_2, pq_priv_kem
+        FROM address_ratchet_keys
+        WHERE conn_id = ? AND ratchet_key_id = ?
+      |]
+      (connId, ratchetKeyId)
+
+deleteOldAddressRatchetKeys :: DB.Connection -> ConnId -> Int -> IO ()
+deleteOldAddressRatchetKeys db connId keep =
+  DB.execute
+    db
+    [sql|
+      DELETE FROM address_ratchet_keys
+      WHERE conn_id = ?
+        AND address_ratchet_key_id NOT IN (
+          SELECT address_ratchet_key_id
+          FROM address_ratchet_keys
+          WHERE conn_id = ?
+          ORDER BY address_ratchet_key_id DESC
+          LIMIT ?
+        )
+    |]
+    (connId, connId, keep)
+
 createSndRatchet :: DB.Connection -> ConnId -> RatchetX448 -> CR.AE2ERatchetParams 'C.X448 -> IO ()
 createSndRatchet db connId ratchetState (CR.AE2ERatchetParams s (CR.E2ERatchetParams _ x3dhPubKey1 x3dhPubKey2 pqPubKem)) =
   DB.execute
@@ -2075,6 +2159,21 @@ instance ConnectionModeI c => ToField (ConnectionRequestUri c) where toField = t
 
 instance (E.Typeable c, ConnectionModeI c) => FromField (ConnectionRequestUri c) where fromField = blobFieldDecoder strDecode
 
+instance ToField RatchetKeyId where toField (RatchetKeyId s) = toField $ Binary s
+
+instance FromField RatchetKeyId where fromField = blobFieldDecoder $ Right . RatchetKeyId
+
+instance ToField ContactRequest where
+  toField = toField . Binary . \case
+    CRInvitation cr -> strEncode cr
+    CRInvitationDR dr -> LB.toStrict $ J.encode dr
+
+instance FromField ContactRequest where
+  fromField = blobFieldDecoder $ \bs ->
+    if "{" `B.isPrefixOf` bs
+      then CRInvitationDR <$> J.eitherDecodeStrict' bs
+      else CRInvitation <$> strDecode bs
+
 instance ToField ConnectionMode where toField = toField . decodeLatin1 . strEncode
 
 instance FromField ConnectionMode where fromField = fromTextField_ connModeT
@@ -2549,7 +2648,7 @@ getConnsData_ deleted' db connIds =
       db
       [sql|
         SELECT user_id, conn_id, conn_mode, smp_agent_version, enable_ntfs,
-          last_external_snd_msg_id, deleted, ratchet_sync_state, pq_support
+          last_external_snd_msg_id, deleted, ratchet_sync_state, pq_support, service_request_expires_at
         FROM connections
         WHERE conn_id IN ? AND deleted = ?
       |]
@@ -2584,7 +2683,7 @@ getConnData deleted' forUpdate db connId' =
       db
       ( [sql|
           SELECT user_id, conn_id, conn_mode, smp_agent_version, enable_ntfs,
-            last_external_snd_msg_id, deleted, ratchet_sync_state, pq_support
+            last_external_snd_msg_id, deleted, ratchet_sync_state, pq_support, service_request_expires_at
           FROM connections
           WHERE conn_id = ? AND deleted = ?
         |]
@@ -2601,9 +2700,9 @@ lockConnForUpdate db connId = do
 #endif
   pure ()
 
-rowToConnData :: (UserId, ConnId, ConnectionMode, VersionSMPA, Maybe BoolInt, PrevExternalSndId, BoolInt, RatchetSyncState, PQSupport) -> (ConnData, ConnectionMode)
-rowToConnData (userId, connId, cMode, connAgentVersion, enableNtfs_, lastExternalSndId, BI deleted, ratchetSyncState, pqSupport) =
-  (ConnData {userId, connId, connAgentVersion, enableNtfs = maybe True unBI enableNtfs_, lastExternalSndId, deleted, ratchetSyncState, pqSupport}, cMode)
+rowToConnData :: (UserId, ConnId, ConnectionMode, VersionSMPA, Maybe BoolInt, PrevExternalSndId, BoolInt, RatchetSyncState, PQSupport, Maybe UTCTime) -> (ConnData, ConnectionMode)
+rowToConnData (userId, connId, cMode, connAgentVersion, enableNtfs_, lastExternalSndId, BI deleted, ratchetSyncState, pqSupport, serviceRequestExpiresAt) =
+  (ConnData {userId, connId, connAgentVersion, enableNtfs = maybe True unBI enableNtfs_, lastExternalSndId, deleted, ratchetSyncState, pqSupport, serviceRequestExpiresAt}, cMode)
 
 setConnDeleted :: DB.Connection -> Bool -> ConnId -> IO ()
 setConnDeleted db waitDelivery connId
@@ -2632,6 +2731,14 @@ updateNewConnJoin db connId aVersion pqSupport enableNtfs =
 getDeletedConnIds :: DB.Connection -> IO [ConnId]
 getDeletedConnIds db = map fromOnly <$> DB.query db "SELECT conn_id FROM connections WHERE deleted = ?" (Only (BI True))
 
+getExpiredServiceConns :: DB.Connection -> UTCTime -> IO [ConnId]
+getExpiredServiceConns db now =
+  map fromOnly <$> DB.query db "SELECT conn_id FROM connections WHERE service_request_expires_at < ? AND deleted = 0 AND deleted_at_wait_delivery IS NULL" (Only now)
+
+deleteExpiredServiceRequests :: DB.Connection -> UTCTime -> IO ()
+deleteExpiredServiceRequests db expireTs =
+  DB.execute db "DELETE FROM conn_invitations WHERE service_request = 1 AND created_at < ?" (Only expireTs)
+
 getDeletedWaitingDeliveryConnIds :: DB.Connection -> IO [ConnId]
 getDeletedWaitingDeliveryConnIds db =
   map fromOnly <$> DB.query_ db "SELECT conn_id FROM connections WHERE deleted_at_wait_delivery IS NOT NULL"

src/Simplex/Messaging/Agent/Store/Postgres/Migrations/App.hs

@@ -13,6 +13,7 @@ import Simplex.Messaging.Agent.Store.Postgres.Migrations.M20251010_client_notice
 import Simplex.Messaging.Agent.Store.Postgres.Migrations.M20251230_strict_tables
 import Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260410_receive_attempts
 import Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260411_service_certs
+import Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260712_address_dr_rpc
 import Simplex.Messaging.Agent.Store.Shared (Migration (..))
 
 schemaMigrations :: [(String, Text, Maybe Text)]
@@ -25,7 +26,8 @@ schemaMigrations =
     ("20251010_client_notices", m20251010_client_notices, Just down_m20251010_client_notices),
     ("20251230_strict_tables", m20251230_strict_tables, Just down_m20251230_strict_tables),
     ("20260410_receive_attempts", m20260410_receive_attempts, Just down_m20260410_receive_attempts),
-    ("20260411_service_certs", m20260411_service_certs, Just down_m20260411_service_certs)
+    ("20260411_service_certs", m20260411_service_certs, Just down_m20260411_service_certs),
+    ("20260712_address_dr_rpc", m20260712_address_dr_rpc, Just down_m20260712_address_dr_rpc)
   ]
 
 -- | The list of migrations in ascending order by date

src/Simplex/Messaging/Agent/Store/Postgres/Migrations/M20260712_address_dr_rpc.hs

@@ -0,0 +1,42 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE QuasiQuotes #-}
+
+module Simplex.Messaging.Agent.Store.Postgres.Migrations.M20260712_address_dr_rpc where
+
+import Data.Text (Text)
+import Text.RawString.QQ (r)
+
+m20260712_address_dr_rpc :: Text
+m20260712_address_dr_rpc =
+  [r|
+CREATE TABLE address_ratchet_keys(
+  address_ratchet_key_id BIGSERIAL PRIMARY KEY,
+  conn_id BYTEA NOT NULL REFERENCES connections ON DELETE CASCADE,
+  ratchet_key_id BYTEA NOT NULL,
+  x3dh_priv_key_1 BYTEA NOT NULL,
+  x3dh_priv_key_2 BYTEA NOT NULL,
+  pq_priv_kem BYTEA,
+  created_at TIMESTAMPTZ NOT NULL DEFAULT (now())
+);
+
+CREATE UNIQUE INDEX idx_address_ratchet_keys ON address_ratchet_keys(conn_id, ratchet_key_id);
+
+ALTER TABLE conn_invitations ADD COLUMN service_request SMALLINT NOT NULL DEFAULT 0; -- service side: received request is a service request (SREQ) not a contact request (REQ)
+ALTER TABLE connections ADD COLUMN created_at TIMESTAMPTZ NOT NULL DEFAULT '1970-01-01 00:00:00';
+ALTER TABLE connections ADD COLUMN service_request_expires_at TIMESTAMPTZ; -- client side: requester's outstanding service request; the time the client stops waiting for the response
+
+CREATE INDEX idx_connections_deleted ON connections(deleted);
+CREATE INDEX idx_connections_service_request_expires_at ON connections(service_request_expires_at);
+  |]
+
+down_m20260712_address_dr_rpc :: Text
+down_m20260712_address_dr_rpc =
+  [r|
+DROP INDEX idx_connections_service_request_expires_at;
+DROP INDEX idx_connections_deleted;
+ALTER TABLE connections DROP COLUMN service_request_expires_at;
+ALTER TABLE connections DROP COLUMN created_at;
+ALTER TABLE conn_invitations DROP COLUMN service_request;
+DROP INDEX idx_address_ratchet_keys;
+DROP TABLE address_ratchet_keys;
+  |]

src/Simplex/Messaging/Agent/Store/Postgres/Migrations/agent_postgres_schema.sql

@@ -104,6 +104,31 @@ CREATE AGGREGATE smp_agent_test_protocol_schema.xor_aggregate(bytea) (
 SET default_table_access_method = heap;
 
 
+CREATE TABLE smp_agent_test_protocol_schema.address_ratchet_keys (
+    address_ratchet_key_id bigint NOT NULL,
+    conn_id bytea NOT NULL,
+    ratchet_key_id bytea NOT NULL,
+    x3dh_priv_key_1 bytea NOT NULL,
+    x3dh_priv_key_2 bytea NOT NULL,
+    pq_priv_kem bytea,
+    created_at timestamp with time zone DEFAULT now() NOT NULL
+);
+
+
+
+CREATE SEQUENCE smp_agent_test_protocol_schema.address_ratchet_keys_address_ratchet_key_id_seq
+    START WITH 1
+    INCREMENT BY 1
+    NO MINVALUE
+    NO MAXVALUE
+    CACHE 1;
+
+
+
+ALTER SEQUENCE smp_agent_test_protocol_schema.address_ratchet_keys_address_ratchet_key_id_seq OWNED BY smp_agent_test_protocol_schema.address_ratchet_keys.address_ratchet_key_id;
+
+
+
 CREATE TABLE smp_agent_test_protocol_schema.client_notices (
     client_notice_id bigint NOT NULL,
     protocol text NOT NULL,
@@ -194,7 +219,8 @@ CREATE TABLE smp_agent_test_protocol_schema.conn_invitations (
     recipient_conn_info bytea NOT NULL,
     accepted smallint DEFAULT 0 NOT NULL,
     own_conn_info bytea,
-    created_at timestamp with time zone DEFAULT now() NOT NULL
+    created_at timestamp with time zone DEFAULT now() NOT NULL,
+    service_request smallint DEFAULT 0 NOT NULL
 );
 
 
@@ -215,7 +241,9 @@ CREATE TABLE smp_agent_test_protocol_schema.connections (
     user_id bigint NOT NULL,
     ratchet_sync_state text DEFAULT 'ok'::text NOT NULL,
     deleted_at_wait_delivery timestamp with time zone,
-    pq_support smallint DEFAULT 0 NOT NULL
+    pq_support smallint DEFAULT 0 NOT NULL,
+    created_at timestamp with time zone DEFAULT '1970-01-01 00:00:00+01'::timestamp with time zone NOT NULL,
+    service_request_expires_at timestamp with time zone
 );
 
 
@@ -847,6 +875,15 @@ ALTER TABLE smp_agent_test_protocol_schema.xftp_servers ALTER COLUMN xftp_server
 
 
 
+ALTER TABLE ONLY smp_agent_test_protocol_schema.address_ratchet_keys ALTER COLUMN address_ratchet_key_id SET DEFAULT nextval('smp_agent_test_protocol_schema.address_ratchet_keys_address_ratchet_key_id_seq'::regclass);
+
+
+
+ALTER TABLE ONLY smp_agent_test_protocol_schema.address_ratchet_keys
+    ADD CONSTRAINT address_ratchet_keys_pkey PRIMARY KEY (address_ratchet_key_id);
+
+
+
 ALTER TABLE ONLY smp_agent_test_protocol_schema.client_notices
     ADD CONSTRAINT client_notices_pkey PRIMARY KEY (client_notice_id);
 
@@ -1032,6 +1069,10 @@ ALTER TABLE ONLY smp_agent_test_protocol_schema.xftp_servers
 
 
 
+CREATE UNIQUE INDEX idx_address_ratchet_keys ON smp_agent_test_protocol_schema.address_ratchet_keys USING btree (conn_id, ratchet_key_id);
+
+
+
 CREATE UNIQUE INDEX idx_client_notices_entity ON smp_agent_test_protocol_schema.client_notices USING btree (protocol, host, port, entity_id);
 
 
@@ -1056,6 +1097,14 @@ CREATE INDEX idx_conn_invitations_contact_conn_id ON smp_agent_test_protocol_sch
 
 
 
+CREATE INDEX idx_connections_deleted ON smp_agent_test_protocol_schema.connections USING btree (deleted);
+
+
+
+CREATE INDEX idx_connections_service_request_expires_at ON smp_agent_test_protocol_schema.connections USING btree (service_request_expires_at);
+
+
+
 CREATE INDEX idx_connections_user ON smp_agent_test_protocol_schema.connections USING btree (user_id);
 
 
@@ -1268,6 +1317,11 @@ CREATE TRIGGER tr_rcv_queue_update AFTER UPDATE ON smp_agent_test_protocol_schem
 
 
 
+ALTER TABLE ONLY smp_agent_test_protocol_schema.address_ratchet_keys
+    ADD CONSTRAINT address_ratchet_keys_conn_id_fkey FOREIGN KEY (conn_id) REFERENCES smp_agent_test_protocol_schema.connections(conn_id) ON DELETE CASCADE;
+
+
+
 ALTER TABLE ONLY smp_agent_test_protocol_schema.client_services
     ADD CONSTRAINT client_services_host_port_fkey FOREIGN KEY (host, port) REFERENCES smp_agent_test_protocol_schema.servers(host, port) ON DELETE RESTRICT;
 

src/Simplex/Messaging/Agent/Store/SQLite.hs

@@ -50,7 +50,6 @@ import Data.Bits (xor)
 import Data.ByteArray (ScrubbedBytes)
 import qualified Data.ByteArray as BA
 import Data.ByteString (ByteString)
-import qualified Data.ByteString as B
 import Data.Functor (($>))
 import Data.IORef
 import Data.Maybe (fromMaybe)

src/Simplex/Messaging/Agent/Store/SQLite/Migrations/App.hs

@@ -49,6 +49,7 @@ import Simplex.Messaging.Agent.Store.SQLite.Migrations.M20251010_client_notices
 import Simplex.Messaging.Agent.Store.SQLite.Migrations.M20251230_strict_tables
 import Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260410_receive_attempts
 import Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260411_service_certs
+import Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260712_address_dr_rpc
 import Simplex.Messaging.Agent.Store.Shared (Migration (..))
 
 schemaMigrations :: [(String, Query, Maybe Query)]
@@ -97,7 +98,8 @@ schemaMigrations =
     ("m20251010_client_notices", m20251010_client_notices, Just down_m20251010_client_notices),
     ("m20251230_strict_tables", m20251230_strict_tables, Just down_m20251230_strict_tables),
     ("m20260410_receive_attempts", m20260410_receive_attempts, Just down_m20260410_receive_attempts),
-    ("m20260411_service_certs", m20260411_service_certs, Just down_m20260411_service_certs)
+    ("m20260411_service_certs", m20260411_service_certs, Just down_m20260411_service_certs),
+    ("m20260712_address_dr_rpc", m20260712_address_dr_rpc, Just down_m20260712_address_dr_rpc)
   ]
 
 -- | The list of migrations in ascending order by date

src/Simplex/Messaging/Agent/Store/SQLite/Migrations/M20260712_address_dr_rpc.hs

@@ -0,0 +1,41 @@
+{-# LANGUAGE QuasiQuotes #-}
+
+module Simplex.Messaging.Agent.Store.SQLite.Migrations.M20260712_address_dr_rpc where
+
+import Database.SQLite.Simple (Query)
+import Database.SQLite.Simple.QQ (sql)
+
+m20260712_address_dr_rpc :: Query
+m20260712_address_dr_rpc =
+  [sql|
+CREATE TABLE address_ratchet_keys(
+  address_ratchet_key_id INTEGER PRIMARY KEY AUTOINCREMENT,
+  conn_id BLOB NOT NULL REFERENCES connections ON DELETE CASCADE,
+  ratchet_key_id BLOB NOT NULL,
+  x3dh_priv_key_1 BLOB NOT NULL,
+  x3dh_priv_key_2 BLOB NOT NULL,
+  pq_priv_kem BLOB,
+  created_at TEXT NOT NULL DEFAULT(datetime('now'))
+) STRICT;
+
+CREATE UNIQUE INDEX idx_address_ratchet_keys ON address_ratchet_keys(conn_id, ratchet_key_id);
+
+ALTER TABLE conn_invitations ADD COLUMN service_request INTEGER NOT NULL DEFAULT 0; -- service side: received request is a service request (SREQ) not a contact request (REQ)
+ALTER TABLE connections ADD COLUMN created_at TEXT NOT NULL DEFAULT('1970-01-01 00:00:00');
+ALTER TABLE connections ADD COLUMN service_request_expires_at TEXT; -- client side: requester's outstanding service request; the time the client stops waiting for the response
+
+CREATE INDEX idx_connections_deleted ON connections(deleted);
+CREATE INDEX idx_connections_service_request_expires_at ON connections(service_request_expires_at);
+  |]
+
+down_m20260712_address_dr_rpc :: Query
+down_m20260712_address_dr_rpc =
+  [sql|
+DROP INDEX idx_connections_service_request_expires_at;
+DROP INDEX idx_connections_deleted;
+ALTER TABLE connections DROP COLUMN service_request_expires_at;
+ALTER TABLE connections DROP COLUMN created_at;
+ALTER TABLE conn_invitations DROP COLUMN service_request;
+DROP INDEX idx_address_ratchet_keys;
+DROP TABLE address_ratchet_keys;
+  |]

src/Simplex/Messaging/Agent/Store/SQLite/Migrations/agent_schema.sql

@@ -27,7 +27,9 @@ CREATE TABLE connections(
   REFERENCES users ON DELETE CASCADE,
   ratchet_sync_state TEXT NOT NULL DEFAULT 'ok',
   deleted_at_wait_delivery TEXT,
-  pq_support INTEGER NOT NULL DEFAULT 0
+  pq_support INTEGER NOT NULL DEFAULT 0,
+  created_at TEXT NOT NULL DEFAULT('1970-01-01 00:00:00'),
+  service_request_expires_at TEXT
 ) WITHOUT ROWID, STRICT;
 CREATE TABLE rcv_queues(
   host TEXT NOT NULL,
@@ -164,6 +166,8 @@ CREATE TABLE conn_invitations(
   accepted INTEGER NOT NULL DEFAULT 0,
   own_conn_info BLOB,
   created_at TEXT NOT NULL DEFAULT(datetime('now'))
+  ,
+  service_request INTEGER NOT NULL DEFAULT 0
 ) WITHOUT ROWID, STRICT;
 CREATE TABLE ratchets(
   conn_id BLOB NOT NULL PRIMARY KEY REFERENCES connections
@@ -465,6 +469,15 @@ CREATE TABLE client_services(
   service_queue_ids_hash BLOB NOT NULL DEFAULT x'00000000000000000000000000000000',
   FOREIGN KEY(host, port) REFERENCES servers ON UPDATE CASCADE ON DELETE RESTRICT
 ) STRICT;
+CREATE TABLE address_ratchet_keys(
+  address_ratchet_key_id INTEGER PRIMARY KEY AUTOINCREMENT,
+  conn_id BLOB NOT NULL REFERENCES connections ON DELETE CASCADE,
+  ratchet_key_id BLOB NOT NULL,
+  x3dh_priv_key_1 BLOB NOT NULL,
+  x3dh_priv_key_2 BLOB NOT NULL,
+  pq_priv_kem BLOB,
+  created_at TEXT NOT NULL DEFAULT(datetime('now'))
+) STRICT;
 CREATE UNIQUE INDEX idx_rcv_queues_ntf ON rcv_queues(host, port, ntf_id);
 CREATE UNIQUE INDEX idx_rcv_queue_id ON rcv_queues(conn_id, rcv_queue_id);
 CREATE UNIQUE INDEX idx_snd_queue_id ON snd_queues(conn_id, snd_queue_id);
@@ -615,6 +628,14 @@ CREATE UNIQUE INDEX idx_server_certs_user_id_host_port ON client_services(
   server_key_hash
 );
 CREATE INDEX idx_server_certs_host_port ON client_services(host, port);
+CREATE UNIQUE INDEX idx_address_ratchet_keys ON address_ratchet_keys(
+  conn_id,
+  ratchet_key_id
+);
+CREATE INDEX idx_connections_deleted ON connections(deleted);
+CREATE INDEX idx_connections_service_request_expires_at ON connections(
+  service_request_expires_at
+);
 CREATE TRIGGER tr_rcv_queue_insert
 AFTER INSERT ON rcv_queues
 FOR EACH ROW

src/Simplex/Messaging/Client.hs

@@ -73,6 +73,8 @@ module Simplex.Messaging.Client
     deleteSMPQueues,
     connectSMPProxiedRelay,
     proxySMPMessage,
+    proxyResolveName,
+    directResolveName,
     forwardSMPTransmission,
     getSMPQueueInfo,
     sendProtocolCommand,
@@ -164,6 +166,7 @@ import Simplex.Messaging.Parsers (defaultJSON, dropPrefix, enumJSON, sumTypeJSON
 import Simplex.Messaging.Protocol
 import Simplex.Messaging.Protocol.Types
 import Simplex.Messaging.Server.QueueStore.QueueInfo
+import Simplex.Messaging.SimplexName (SimplexDomain)
 import Simplex.Messaging.TMap (TMap)
 import qualified Simplex.Messaging.TMap as TM
 import Simplex.Messaging.Transport
@@ -224,10 +227,10 @@ smpClientStub g sessionId thVersion thAuth = do
               thServerVRange = supportedServerSMPRelayVRange,
               thAuth,
               blockSize = smpBlockSize,
-              implySessId = thVersion >= authCmdsSMPVersion,
+              implySessId = True,
               encryptBlock = Nothing,
-              batch = True,
-              serviceAuth = thVersion >= serviceCertsSMPVersion
+              serviceAuth = thVersion >= serviceCertsSMPVersion,
+              serverInfo = Nothing
             },
         sessionTs = ts,
         client_ =
@@ -971,7 +974,7 @@ deleteSMPQueueLink :: SMPClient -> NetworkRequestMode -> RcvPrivateAuthKey -> Re
 deleteSMPQueueLink = okSMPCommand LDEL
 {-# INLINE deleteSMPQueueLink #-}
 
--- | Get 1-time inviation SMP queue link data and secure the queue via queue link ID.
+-- | Get 1-time invitation SMP queue link data and secure the queue via queue link ID.
 secureGetSMPQueueLink :: SMPClient -> NetworkRequestMode -> SndPrivateAuthKey -> LinkId -> ExceptT SMPClientError IO (SenderId, QueueLinkData)
 secureGetSMPQueueLink c nm spKey lnkId =
   sendSMPCommand c nm (Just spKey) lnkId (LKEY $ C.toPublic spKey) >>= \case
@@ -1046,6 +1049,33 @@ sendSMPMessage c nm spKey sId flags msg =
 proxySMPMessage :: SMPClient -> NetworkRequestMode -> ProxiedRelay -> Maybe SndPrivateAuthKey -> SenderId -> MsgFlags -> MsgBody -> ExceptT SMPClientError IO (Either ProxyClientError ())
 proxySMPMessage c nm proxiedRelay spKey sId flags msg = proxyOKSMPCommand c nm proxiedRelay spKey sId (SEND flags msg)
 
+-- | Resolve a public-namespace name via PFWD. Preferred path - hides the
+-- client IP from the resolver. Mirrors `proxySMPMessage`'s shape; routes
+-- through `proxySMPCommand` and pattern-matches the expected RNAME response.
+-- Version-gated on the destination relay (mirrors `connectSMPProxiedRelay`):
+-- the client never sends RSLV to a relay that predates names support.
+proxyResolveName :: SMPClient -> NetworkRequestMode -> ProxiedRelay -> SimplexDomain -> ExceptT SMPClientError IO (Either ProxyClientError NameRecord)
+proxyResolveName c nm proxiedRelay name
+  | prVersion proxiedRelay >= namesSMPVersion =
+      proxySMPCommand c nm proxiedRelay Nothing NoEntity (RSLV name) >>= \case
+        Right (RNAME nr) -> pure $ Right nr
+        Right r -> throwE $ unexpectedResponse r
+        Left e -> pure $ Left e
+  | otherwise = throwE $ PCETransportError TEVersion
+
+-- | Direct (non-PFWD) name resolution. Exposes the client IP to the resolver;
+-- callers that want anonymity should use `proxyResolveName` via the standard
+-- proxy fallback in the agent. RSLV requires no entity ID or authorization
+-- (see `noAuthCmd` in Protocol.hs). Version-gated on the session here, not the
+-- encoder, so an old server never receives RSLV.
+directResolveName :: SMPClient -> NetworkRequestMode -> SimplexDomain -> ExceptT SMPClientError IO NameRecord
+directResolveName c nm name
+  | thVersion (thParams c) >= namesSMPVersion =
+      sendProtocolCommand c nm Nothing NoEntity (Cmd SResolver (RSLV name)) >>= \case
+        RNAME nr -> pure nr
+        r -> throwE $ unexpectedResponse r
+  | otherwise = throwE $ PCETransportError TEVersion
+
 -- | Acknowledge message delivery (server deletes the message).
 --
 -- https://github.com/simplex-chat/simplexmq/blob/master/protocol/simplex-messaging.md#acknowledge-message-delivery
@@ -1080,17 +1110,15 @@ deleteSMPQueues = okSMPCommands DEL
 -- send PRXY :: SMPServer -> Maybe BasicAuth -> Command Sender
 -- receives PKEY :: SessionId -> X.CertificateChain -> X.SignedExact X.PubKey -> BrokerMsg
 connectSMPProxiedRelay :: SMPClient -> NetworkRequestMode -> SMPServer -> Maybe BasicAuth -> ExceptT SMPClientError IO ProxiedRelay
-connectSMPProxiedRelay c@ProtocolClient {client_ = PClient {tcpConnectTimeout, tcpTimeout}} nm relayServ@ProtocolServer {port = relayPort, keyHash = C.KeyHash kh} proxyAuth
-  | thVersion (thParams c) >= sendingProxySMPVersion =
-      sendProtocolCommand_ c nm Nothing tOut Nothing NoEntity (Cmd SProxiedClient (PRXY relayServ proxyAuth)) >>= \case
-        PKEY sId vr (CertChainPubKey chain key) ->
-          case supportedClientSMPRelayVRange `compatibleVersion` vr of
-            Nothing -> throwE $ transportErr TEVersion
-            Just (Compatible v) -> do
-              relayKey <- liftEitherWith (const $ transportErr $ TEHandshake IDENTITY) =<< liftIO (runExceptT $ validateRelay chain key)
-              pure $ ProxiedRelay sId v proxyAuth relayKey
-        r -> throwE $ unexpectedResponse r
-  | otherwise = throwE $ PCETransportError TEVersion
+connectSMPProxiedRelay c@ProtocolClient {client_ = PClient {tcpConnectTimeout, tcpTimeout}} nm relayServ@ProtocolServer {port = relayPort, keyHash = C.KeyHash kh} proxyAuth =
+  sendProtocolCommand_ c nm Nothing tOut Nothing NoEntity (Cmd SProxiedClient (PRXY relayServ proxyAuth)) >>= \case
+    PKEY sId vr (CertChainPubKey chain key) ->
+      case supportedClientSMPRelayVRange `compatibleVersion` vr of
+        Nothing -> throwE $ transportErr TEVersion
+        Just (Compatible v) -> do
+          relayKey <- liftEitherWith (const $ transportErr $ TEHandshake IDENTITY) =<< liftIO (runExceptT $ validateRelay chain key)
+          pure $ ProxiedRelay sId v proxyAuth relayKey
+    r -> throwE $ unexpectedResponse r
   where
     tOut = Just $ netTimeoutInt tcpConnectTimeout nm + netTimeoutInt tcpTimeout nm
     transportErr = PCEProtocolError . PROXY . BROKER . TRANSPORT
@@ -1321,7 +1349,7 @@ sendProtocolCommand c nm = sendProtocolCommand_ c nm Nothing Nothing
 --
 -- Please note: if nonce is passed it is also used as a correlation ID
 sendProtocolCommand_ :: forall v err msg. Protocol v err msg => ProtocolClient v err msg -> NetworkRequestMode -> Maybe C.CbNonce -> Maybe Int -> Maybe C.APrivateAuthKey -> EntityId -> ProtoCommand msg -> ExceptT (ProtocolClientError err) IO msg
-sendProtocolCommand_ c@ProtocolClient {client_ = PClient {sndQ}, thParams = THandleParams {batch, blockSize, serviceAuth}} nm nonce_ tOut pKey entId cmd =
+sendProtocolCommand_ c@ProtocolClient {client_ = PClient {sndQ}, thParams = THandleParams {blockSize, serviceAuth}} nm nonce_ tOut pKey entId cmd =
   ExceptT $ uncurry sendRecv =<< mkTransmission_ c nonce_ (entId, pKey, cmd)
   where
     -- two separate "atomically" needed to avoid blocking
@@ -1334,9 +1362,7 @@ sendProtocolCommand_ c@ProtocolClient {client_ = PClient {sndQ}, thParams = THan
             nonBlockingWriteTBQueue sndQ (Just r, s)
             response <$> getResponse c nm tOut r
         where
-          s
-            | batch = tEncodeBatch1 serviceAuth t
-            | otherwise = tEncode serviceAuth t
+          s = tEncodeBatch1 serviceAuth t
 
 nonBlockingWriteTBQueue :: TBQueue a -> a -> IO ()
 nonBlockingWriteTBQueue q x = do

src/Simplex/Messaging/Client/Agent.hs

@@ -107,7 +107,7 @@ data SMPClientAgentConfig = SMPClientAgentConfig
   { smpCfg :: ProtocolClientConfig SMPVersion,
     reconnectInterval :: RetryInterval,
     persistErrorInterval :: NominalDiffTime,
-    msgQSize :: Natural,
+    msgQSize :: Maybe Natural,
     agentQSize :: Natural,
     agentSubsBatchSize :: Int,
     ownServerDomains :: [ByteString]
@@ -124,7 +124,7 @@ defaultSMPClientAgentConfig =
             maxInterval = 10 * second
           },
       persistErrorInterval = 30, -- seconds
-      msgQSize = 2048,
+      msgQSize = Just 2048,
       agentQSize = 2048,
       agentSubsBatchSize = 1360,
       ownServerDomains = []
@@ -138,7 +138,7 @@ data SMPClientAgent p = SMPClientAgent
     dbService :: Maybe DBService,
     active :: TVar Bool,
     startedAt :: UTCTime,
-    msgQ :: TBQueue (ServerTransmissionBatch SMPVersion ErrorType BrokerMsg),
+    msgQ :: Maybe (TBQueue (ServerTransmissionBatch SMPVersion ErrorType BrokerMsg)),
     agentQ :: TBQueue SMPClientAgentEvent,
     randomDrg :: TVar ChaChaDRG,
     smpClients :: TMap SMPServer SMPClientVar,
@@ -162,7 +162,8 @@ newSMPClientAgent :: SParty p -> SMPClientAgentConfig -> Maybe DBService -> TVar
 newSMPClientAgent agentParty agentCfg@SMPClientAgentConfig {msgQSize, agentQSize} dbService randomDrg = do
   active <- newTVarIO True
   startedAt <- getCurrentTime
-  msgQ <- newTBQueueIO msgQSize
+  -- Only subscribing agents receive server transmissions, should not be created until processed to prevent deadlock.
+  msgQ <- mapM newTBQueueIO msgQSize
   agentQ <- newTBQueueIO agentQSize
   smpClients <- TM.emptyIO
   smpSessions <- TM.emptyIO
@@ -205,11 +206,8 @@ getSMPServerClient' ca srv = snd <$> getSMPServerClient'' ca srv
 getSMPServerClient'' :: SMPClientAgent p -> SMPServer -> ExceptT SMPClientError IO (OwnServer, SMPClient)
 getSMPServerClient'' ca@SMPClientAgent {agentCfg, smpClients, smpSessions, workerSeq} srv = do
   ts <- liftIO getCurrentTime
-  atomically (getClientVar ts) >>= either (ExceptT . newSMPClient) waitForSMPClient
+  withGetSessVar workerSeq srv smpClients ts (ExceptT . newSMPClient) waitForSMPClient
   where
-    getClientVar :: UTCTime -> STM (Either SMPClientVar SMPClientVar)
-    getClientVar = getSessVar workerSeq srv smpClients
-
     waitForSMPClient :: SMPClientVar -> ExceptT SMPClientError IO (OwnServer, SMPClient)
     waitForSMPClient v = do
       let ProtocolClientConfig {networkConfig = NetworkConfig {tcpConnectTimeout}} = smpCfg agentCfg
@@ -267,7 +265,7 @@ connectClient ca@SMPClientAgent {agentCfg, dbService, smpClients, smpSessions, m
   Nothing -> getClient cfg
   where
     cfg = smpCfg agentCfg
-    getClient cfg' = getProtocolClient randomDrg NRMBackground (1, srv, Nothing) cfg' [] (Just msgQ) startedAt clientDisconnected
+    getClient cfg' = getProtocolClient randomDrg NRMBackground (1, srv, Nothing) cfg' [] msgQ startedAt clientDisconnected
 
     clientDisconnected :: SMPClient -> IO ()
     clientDisconnected smp = do

src/Simplex/Messaging/Compression.hs

@@ -8,6 +8,7 @@ module Simplex.Messaging.Compression
     compress1,
     decompress1,
     limitDecompress1,
+    limitDecompress',
     decompressedSize,
   ) where
 
@@ -57,9 +58,12 @@ decompress1 = \case
 limitDecompress1 :: Int -> Compressed -> Either String ByteString
 limitDecompress1 limit = \case
   Passthrough bs -> Right bs
-  Compressed (Large bs) -> case Z1.decompressedSize bs of
-    Just sz | sz <= limit -> decompress_ bs
-    _ -> Left $ "compressed size not specified or exceeds " <> show limit
+  Compressed (Large bs) -> limitDecompress' limit bs
+
+limitDecompress' :: Int -> ByteString -> Either String ByteString
+limitDecompress' limit bs = case Z1.decompressedSize bs of
+  Just sz | sz <= limit -> decompress_ bs
+  _ -> Left $ "compressed size not specified or exceeds " <> show limit
 
 decompress_ :: ByteString -> Either String ByteString
 decompress_ bs = case Z1.decompress bs of

src/Simplex/Messaging/Crypto.hs

@@ -61,6 +61,7 @@ module Simplex.Messaging.Crypto
     APublicAuthKey (..),
     CryptoPublicKey (..),
     CryptoPrivateKey (..),
+    StoredPrivateKey (..),
     AAuthKeyPair,
     KeyPair,
     KeyPairX25519,
@@ -342,8 +343,17 @@ deriving instance Eq (PrivateKey a)
 
 deriving instance Show (PrivateKey a)
 
--- Do not enable, to avoid leaking key data
--- instance StrEncoding (PrivateKey Ed25519) where
+-- Do not enable, to avoid leaking key data, use StoredPrivateKey instead
+-- instance StrEncoding (PrivateKey a) where
+
+newtype StoredPrivateKey a = StoredPrivateKey {unStored :: PrivateKey a}
+  deriving (Show)
+
+instance AlgorithmI a => StrEncoding (StoredPrivateKey a) where
+  strEncode = strEncode . encodePrivKey . unStored
+  {-# INLINE strEncode #-}
+  strDecode = fmap StoredPrivateKey . decodePrivKey
+  {-# INLINE strDecode #-}
 
 -- Used in notification store log
 instance StrEncoding (PrivateKey X25519) where

src/Simplex/Messaging/Crypto/BBS.hs

@@ -0,0 +1,302 @@
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE DerivingStrategies #-}
+{-# LANGUAGE DerivingVia #-}
+{-# LANGUAGE ForeignFunctionInterface #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
+{-# LANGUAGE KindSignatures #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+
+-- | FFI bindings to libbbs (BBS+ signatures over BLS12-381, SHA-256 suite).
+-- Values parsed from untrusted input are length-validated; see FixedBS and the
+-- BBSProof StrEncoding instance.
+module Simplex.Messaging.Crypto.BBS
+  ( BBSSecretKey (..),
+    BBSPublicKey (..),
+    BBSKeyPair,
+    BBSSignature (..),
+    BBSProof (..),
+    BBSHeader (..),
+    BBSPresHeader (..),
+    bbsKeyGen,
+    bbsPublicKey,
+    bbsSign,
+    bbsVerify,
+    bbsProofGen,
+    bbsProofVerify,
+  ) where
+
+import Data.Aeson (FromJSON, ToJSON)
+import Data.ByteString (ByteString)
+import qualified Data.ByteString as B
+import qualified Data.ByteString.Unsafe as BU
+import Data.Proxy (Proxy (..))
+import Foreign
+import Foreign.C
+import GHC.TypeLits (KnownNat, KnownSymbol, Nat, Symbol, natVal, symbolVal)
+import Simplex.Messaging.Encoding.String
+import System.IO.Unsafe (unsafePerformIO)
+
+-- Note: the data constructors below are unchecked escape hatches for trusted,
+-- internally-produced values (e.g. keygen output). Any value parsed from
+-- untrusted input (StrEncoding / FromJSON) is length-validated — see FixedBS
+-- and the BBSProof StrEncoding instance.
+
+newtype BBSSecretKey = BBSSecretKey ByteString
+  deriving newtype (Eq, Show)
+  deriving (StrEncoding) via (FixedBS "BBSSecretKey" 32)
+  deriving (ToJSON, FromJSON) via (StrJSON "BBSSecretKey" BBSSecretKey)
+
+newtype BBSPublicKey = BBSPublicKey ByteString
+  deriving newtype (Eq, Show)
+  deriving (StrEncoding) via (FixedBS "BBSPublicKey" 96)
+  deriving (ToJSON, FromJSON) via (StrJSON "BBSPublicKey" BBSPublicKey)
+
+type BBSKeyPair = (BBSPublicKey, BBSSecretKey)
+
+newtype BBSSignature = BBSSignature ByteString
+  deriving newtype (Eq, Show)
+  deriving (StrEncoding) via (FixedBS "BBSSignature" 80)
+  deriving (ToJSON, FromJSON) via (StrJSON "BBSSignature" BBSSignature)
+
+newtype BBSProof = BBSProof ByteString
+  deriving newtype (Eq, Show)
+  deriving (ToJSON, FromJSON) via (StrJSON "BBSProof" BBSProof)
+
+newtype BBSHeader = BBSHeader ByteString
+  deriving newtype (Eq, Show, StrEncoding)
+  deriving (ToJSON, FromJSON) via (StrJSON "BBSHeader" BBSHeader)
+
+newtype BBSPresHeader = BBSPresHeader ByteString
+  deriving newtype (Eq, Show, StrEncoding)
+  deriving (ToJSON, FromJSON) via (StrJSON "BBSPresHeader" BBSPresHeader)
+
+-- | A ByteString validated to be exactly @n@ bytes when parsed via StrEncoding
+-- (and the JSON derived from it). Local to BBS, where every key/signature is a
+-- fixed size; @name@ appears in the decode error only.
+newtype FixedBS (name :: Symbol) (n :: Nat) = FixedBS ByteString
+
+instance forall name n. (KnownSymbol name, KnownNat n) => StrEncoding (FixedBS name n) where
+  strEncode (FixedBS bs) = strEncode bs
+  strP = do
+    bs <- base64urlP
+    let n = fromIntegral (natVal (Proxy :: Proxy n))
+    if B.length bs == n
+      then pure (FixedBS bs)
+      else fail $ symbolVal (Proxy :: Proxy name) <> ": expected " <> show n <> " bytes, got " <> show (B.length bs)
+
+-- Constants
+
+bbsSkLen, bbsPkLen, bbsSigLen, bbsProofBaseLen, bbsProofUdElemLen :: Int
+bbsSkLen = 32
+bbsPkLen = 96
+bbsSigLen = 80
+bbsProofBaseLen = 272
+bbsProofUdElemLen = 32
+
+bbsProofLen :: Int -> Int
+bbsProofLen numUndisclosed = bbsProofBaseLen + numUndisclosed * bbsProofUdElemLen
+
+-- | A proof is @bbsProofBaseLen + 32 * numUndisclosed@ bytes; reject anything else.
+instance StrEncoding BBSProof where
+  strEncode (BBSProof bs) = strEncode bs
+  strP = do
+    bs <- base64urlP
+    let len = B.length bs
+    if len >= bbsProofBaseLen && (len - bbsProofBaseLen) `mod` bbsProofUdElemLen == 0
+      then pure (BBSProof bs)
+      else fail $ "BBS: invalid proof length " <> show len
+
+-- FFI
+
+data BBS_Ciphersuite
+
+foreign import ccall "bbs_keygen_full"
+  c_bbs_keygen_full :: Ptr BBS_Ciphersuite -> Ptr Word8 -> Ptr Word8 -> IO CInt
+
+foreign import ccall "bbs_sk_to_pk"
+  c_bbs_sk_to_pk :: Ptr BBS_Ciphersuite -> Ptr Word8 -> Ptr Word8 -> IO CInt
+
+foreign import ccall "bbs_sign"
+  c_bbs_sign ::
+    Ptr BBS_Ciphersuite ->
+    Ptr Word8 -> Ptr Word8 -> Ptr Word8 ->
+    Ptr Word8 -> CSize ->
+    CSize -> Ptr (Ptr Word8) -> Ptr CSize ->
+    IO CInt
+
+foreign import ccall "bbs_verify"
+  c_bbs_verify ::
+    Ptr BBS_Ciphersuite ->
+    Ptr Word8 -> Ptr Word8 ->
+    Ptr Word8 -> CSize ->
+    CSize -> Ptr (Ptr Word8) -> Ptr CSize ->
+    IO CInt
+
+foreign import ccall "bbs_proof_gen"
+  c_bbs_proof_gen ::
+    Ptr BBS_Ciphersuite ->
+    Ptr Word8 -> Ptr Word8 -> Ptr Word8 ->
+    Ptr Word8 -> CSize ->
+    Ptr Word8 -> CSize ->
+    Ptr CSize -> CSize ->
+    CSize -> Ptr (Ptr Word8) -> Ptr CSize ->
+    IO CInt
+
+foreign import ccall "bbs_proof_verify"
+  c_bbs_proof_verify ::
+    Ptr BBS_Ciphersuite ->
+    Ptr Word8 ->
+    Ptr Word8 -> CSize ->
+    Ptr Word8 -> CSize ->
+    Ptr Word8 -> CSize ->
+    Ptr CSize -> CSize ->
+    CSize -> Ptr (Ptr Word8) -> Ptr CSize ->
+    IO CInt
+
+foreign import ccall "&bbs_sha256_ciphersuite"
+  c_bbs_sha256_ciphersuite :: Ptr (Ptr BBS_Ciphersuite)
+
+-- The ciphersuite is a static const pointer in libbbs; read it once.
+ciphersuite :: Ptr BBS_Ciphersuite
+ciphersuite = unsafePerformIO $ peek c_bbs_sha256_ciphersuite
+{-# NOINLINE ciphersuite #-}
+
+-- Helpers
+
+withBS :: ByteString -> (Ptr Word8 -> CSize -> IO a) -> IO a
+withBS bs f = BU.unsafeUseAsCStringLen bs $ \(p, l) -> f (castPtr p) (fromIntegral l)
+
+packPtr :: Ptr Word8 -> Int -> IO ByteString
+packPtr ptr len = B.packCStringLen (castPtr ptr, len)
+
+-- Marshals a list of messages into parallel pointer/length arrays. Each
+-- ByteString is held alive (via nested unsafeUseAsCStringLen) until @f@ returns,
+-- so the C callee never sees a pointer to freed memory.
+withMessages :: [ByteString] -> (Ptr (Ptr Word8) -> Ptr CSize -> CSize -> IO a) -> IO a
+withMessages msgs f = go msgs []
+  where
+    go [] acc =
+      let cstrs = reverse acc
+       in withArray (map fst cstrs) $ \msgsPtr ->
+            withArray (map snd cstrs) $ \lensPtr ->
+              f msgsPtr lensPtr (fromIntegral $ length cstrs)
+    go (m : ms) acc =
+      BU.unsafeUseAsCStringLen m $ \(p, l) ->
+        go ms ((castPtr p :: Ptr Word8, fromIntegral l :: CSize) : acc)
+
+withIndexes :: [Int] -> (Ptr CSize -> CSize -> IO a) -> IO a
+withIndexes idxs f =
+  withArrayLen (map fromIntegral idxs :: [CSize]) $ \n ptr -> f ptr (fromIntegral n)
+
+-- libbbs expects disclosed indexes strictly ascending and in [0, total). This
+-- both matches the spec and guarantees the output-buffer size we compute matches
+-- what libbbs writes (no out-of-bounds write from a bad index list).
+ascendingInRange :: [Int] -> Int -> Bool
+ascendingInRange idxs total =
+  all (\i -> i >= 0 && i < total) idxs && and (zipWith (<) idxs (drop 1 idxs))
+
+-- Public API
+
+bbsKeyGen :: IO (Either String BBSKeyPair)
+bbsKeyGen =
+  allocaBytes bbsSkLen $ \skPtr ->
+    allocaBytes bbsPkLen $ \pkPtr -> do
+      rc <- c_bbs_keygen_full ciphersuite skPtr pkPtr
+      if rc /= 0
+        then pure $ Left "bbsKeyGen failed"
+        else do
+          sk <- packPtr skPtr bbsSkLen
+          pk <- packPtr pkPtr bbsPkLen
+          pure $ Right (BBSPublicKey pk, BBSSecretKey sk)
+
+bbsPublicKey :: BBSSecretKey -> IO (Either String BBSPublicKey)
+bbsPublicKey (BBSSecretKey sk) =
+  allocaBytes bbsPkLen $ \pkPtr ->
+    withBS sk $ \skPtr _ -> do
+      rc <- c_bbs_sk_to_pk ciphersuite skPtr pkPtr
+      if rc /= 0
+        then pure $ Left "bbsPublicKey failed"
+        else Right . BBSPublicKey <$> packPtr pkPtr bbsPkLen
+
+bbsSign ::
+  BBSSecretKey ->
+  BBSHeader ->
+  [ByteString] ->
+  IO (Either String BBSSignature)
+bbsSign secret@(BBSSecretKey sk) (BBSHeader header) msgs =
+  bbsPublicKey secret >>= either (pure . Left) sign'
+  where
+    sign' (BBSPublicKey pk) =
+      allocaBytes bbsSigLen $ \sigPtr ->
+        withBS sk $ \skPtr _ ->
+          withBS pk $ \pkPtr _ ->
+            withBS header $ \hdrPtr hdrLen ->
+              withMessages msgs $ \msgsPtr lensPtr n -> do
+                rc <- c_bbs_sign ciphersuite skPtr pkPtr sigPtr hdrPtr hdrLen n msgsPtr lensPtr
+                if rc /= 0
+                  then pure $ Left "bbsSign failed"
+                  else Right . BBSSignature <$> packPtr sigPtr bbsSigLen
+
+bbsVerify ::
+  BBSPublicKey ->
+  BBSSignature ->
+  BBSHeader ->
+  [ByteString] ->
+  IO Bool
+bbsVerify (BBSPublicKey pk) (BBSSignature sig) (BBSHeader header) msgs =
+  withBS pk $ \pkPtr _ ->
+    withBS sig $ \sigPtr _ ->
+      withBS header $ \hdrPtr hdrLen ->
+        withMessages msgs $ \msgsPtr lensPtr n -> do
+          rc <- c_bbs_verify ciphersuite pkPtr sigPtr hdrPtr hdrLen n msgsPtr lensPtr
+          pure (rc == 0)
+
+bbsProofGen ::
+  BBSPublicKey ->
+  BBSSignature ->
+  BBSHeader ->
+  BBSPresHeader ->
+  [Int] ->
+  [ByteString] ->
+  IO (Either String BBSProof)
+bbsProofGen (BBSPublicKey pk) (BBSSignature sig) (BBSHeader header) (BBSPresHeader ph) disclosedIdxs msgs
+  | not (ascendingInRange disclosedIdxs (length msgs)) = pure $ Left "bbsProofGen: invalid disclosed indexes"
+  | otherwise =
+  allocaBytes proofSz $ \proofPtr ->
+    withBS pk $ \pkPtr _ ->
+      withBS sig $ \sigPtr _ ->
+        withBS header $ \hdrPtr hdrLen ->
+          withBS ph $ \phPtr phLen ->
+            withIndexes disclosedIdxs $ \idxsPtr idxsLen ->
+              withMessages msgs $ \msgsPtr lensPtr n -> do
+                rc <- c_bbs_proof_gen ciphersuite pkPtr sigPtr proofPtr hdrPtr hdrLen phPtr phLen idxsPtr idxsLen n msgsPtr lensPtr
+                if rc /= 0
+                  then pure $ Left "bbsProofGen failed"
+                  else Right . BBSProof <$> packPtr proofPtr proofSz
+  where
+    numUndisclosed = length msgs - length disclosedIdxs
+    proofSz = bbsProofLen numUndisclosed
+
+bbsProofVerify ::
+  BBSPublicKey ->
+  BBSProof ->
+  BBSHeader ->
+  BBSPresHeader ->
+  [Int] ->
+  Int ->
+  [ByteString] ->
+  IO Bool
+bbsProofVerify (BBSPublicKey pk) (BBSProof proof) (BBSHeader header) (BBSPresHeader ph) disclosedIdxs numMessages disclosedMsgs
+  | numMessages < 0 = pure False
+  | length disclosedIdxs /= length disclosedMsgs = pure False
+  | not (ascendingInRange disclosedIdxs numMessages) = pure False
+  | B.length proof /= bbsProofLen (numMessages - length disclosedIdxs) = pure False
+  | otherwise =
+  withBS pk $ \pkPtr _ ->
+    withBS proof $ \proofPtr proofLen ->
+      withBS header $ \hdrPtr hdrLen ->
+        withBS ph $ \phPtr phLen ->
+          withIndexes disclosedIdxs $ \idxsPtr idxsLen ->
+            withMessages disclosedMsgs $ \msgsPtr lensPtr _ -> do
+              rc <- c_bbs_proof_verify ciphersuite pkPtr proofPtr proofLen hdrPtr hdrLen phPtr phLen idxsPtr idxsLen (fromIntegral numMessages) msgsPtr lensPtr
+              pure (rc == 0)

src/Simplex/Messaging/Crypto/Ratchet.hs

@@ -37,6 +37,7 @@ module Simplex.Messaging.Crypto.Ratchet
     AUseKEM (..),
     RatchetKEMState (..),
     SRatchetKEMState (..),
+    RatchetKEMStateI (..),
     RcvPrivRKEMParams,
     APrivRKEMParams (..),
     RcvE2ERatchetParamsUri,
@@ -45,12 +46,11 @@ module Simplex.Messaging.Crypto.Ratchet
     AE2ERatchetParams (..),
     E2ERatchetParamsUri (..),
     E2ERatchetParams (..),
+    RcvE2EPrivRatchetParams,
     VersionE2E,
     VersionRangeE2E,
     pattern VersionE2E,
     RatchetVersions (..),
-    kdfX3DHE2EEncryptVersion,
-    pqRatchetE2EEncryptVersion,
     currentE2EEncryptVersion,
     supportedE2EEncryptVRange,
     generateRcvE2EParams,
@@ -85,8 +85,6 @@ module Simplex.Messaging.Crypto.Ratchet
     RatchetKey (..),
     fullHeaderLen,
     applySMDiff,
-    encodeMsgHeader,
-    msgHeaderP,
   )
 where
 
@@ -100,7 +98,6 @@ import Crypto.Random (ChaChaDRG)
 import Data.Aeson (FromJSON (..), ToJSON (..))
 import qualified Data.Aeson as J
 import qualified Data.Aeson.TH as JQ
-import Data.Attoparsec.ByteString (Parser, peekWord8')
 import qualified Data.Attoparsec.ByteString.Char8 as A
 import qualified Data.ByteArray as BA
 import Data.ByteString.Char8 (ByteString)
@@ -130,6 +127,7 @@ import UnliftIO.STM
 -- e2e encryption headers version history:
 -- 1 - binary protocol encoding (1/1/2022)
 -- 2 - use KDF in x3dh (10/20/2022)
+-- 3 - PQDR (3/14/2024)
 
 data E2EVersion
 
@@ -142,17 +140,17 @@ type VersionRangeE2E = VersionRange E2EVersion
 pattern VersionE2E :: Word16 -> VersionE2E
 pattern VersionE2E v = Version v
 
-kdfX3DHE2EEncryptVersion :: VersionE2E
-kdfX3DHE2EEncryptVersion = VersionE2E 2
+_pqRatchetE2EEncryptVersion :: VersionE2E
+_pqRatchetE2EEncryptVersion = VersionE2E 3
 
-pqRatchetE2EEncryptVersion :: VersionE2E
-pqRatchetE2EEncryptVersion = VersionE2E 3
+minSupportedE2EEncryptVersion :: VersionE2E
+minSupportedE2EEncryptVersion = _pqRatchetE2EEncryptVersion
 
 currentE2EEncryptVersion :: VersionE2E
 currentE2EEncryptVersion = VersionE2E 3
 
 supportedE2EEncryptVRange :: VersionRangeE2E
-supportedE2EEncryptVRange = mkVersionRange kdfX3DHE2EEncryptVersion currentE2EEncryptVersion
+supportedE2EEncryptVRange = mkVersionRange minSupportedE2EEncryptVersion currentE2EEncryptVersion
 
 data RatchetKEMState
   = RKSProposed -- only KEM encapsulation key
@@ -236,9 +234,7 @@ data AnyE2ERatchetParams
 deriving instance Show AnyE2ERatchetParams
 
 instance (RatchetKEMStateI s, AlgorithmI a) => Encoding (E2ERatchetParams s a) where
-  smpEncode (E2ERatchetParams v k1 k2 kem_)
-    | v >= pqRatchetE2EEncryptVersion = smpEncode (v, k1, k2, kem_)
-    | otherwise = smpEncode (v, k1, k2)
+  smpEncode (E2ERatchetParams v k1 k2 kem_) = smpEncode (v, k1, k2, kem_)
   smpP = toParams <$?> smpP
     where
       toParams :: AE2ERatchetParams a -> Either String (E2ERatchetParams s a)
@@ -259,14 +255,9 @@ instance Encoding AnyE2ERatchetParams where
     case testEquality a a' of
       Nothing -> fail "bad e2e params: different key algorithms"
       Just Refl ->
-        kemP v >>= \case
+        smpP >>= \case
           Just (ARKP s kem) -> pure $ AnyE2ERatchetParams s a $ E2ERatchetParams v k1 k2 (Just kem)
           Nothing -> pure $ AnyE2ERatchetParams SRKSProposed a $ E2ERatchetParams v k1 k2 Nothing
-    where
-      kemP :: VersionE2E -> Parser (Maybe ARKEMParams)
-      kemP v
-        | v >= pqRatchetE2EEncryptVersion = smpP
-        | otherwise = pure Nothing
 
 instance VersionI E2EVersion (E2ERatchetParams s a) where
   type VersionRangeT E2EVersion (E2ERatchetParams s a) = E2ERatchetParamsUri s a
@@ -305,11 +296,10 @@ instance (RatchetKEMStateI s, AlgorithmI a) => StrEncoding (E2ERatchetParamsUri
       [("v", strEncode vs), ("x3dh", strEncodeList [key1, key2])]
         <> maybe [] encodeKem kem_
     where
-      encodeKem kem
-        | maxVersion vs < pqRatchetE2EEncryptVersion = []
-        | otherwise = case kem of
-            RKParamsProposed k -> [("kem_key", strEncode k)]
-            RKParamsAccepted ct k -> [("kem_ct", strEncode ct), ("kem_key", strEncode k)]
+      encodeKem :: RKEMParams s -> [(ByteString, ByteString)]
+      encodeKem kem  = case kem of
+        RKParamsProposed k -> [("kem_key", strEncode k)]
+        RKParamsAccepted ct k -> [("kem_ct", strEncode ct), ("kem_key", strEncode k)]
   strP = toE2ERatchetParamsUri <$?> strP
   {-# INLINE strP #-}
 
@@ -326,25 +316,26 @@ instance StrEncoding AnyE2ERatchetParamsUri where
   strEncode (AnyE2ERatchetParamsUri _ _ ps) = strEncode ps
   strP = do
     query <- strP
-    vr :: VersionRangeE2E <- queryParam "v" query
+    vr :: VersionRangeE2E <- adjustE2EVRange <$> queryParam "v" query
     keys <- L.toList <$> queryParam "x3dh" query
     case keys of
       [APublicDhKey a k1, APublicDhKey a' k2] -> case testEquality a a' of
         Nothing -> fail "bad e2e params: different key algorithms"
         Just Refl ->
-          kemP vr query >>= \case
+          kemP query >>= \case
             Just (ARKP s kem) -> pure $ AnyE2ERatchetParamsUri s a $ E2ERatchetParamsUri vr k1 k2 (Just kem)
             Nothing -> pure $ AnyE2ERatchetParamsUri SRKSProposed a $ E2ERatchetParamsUri vr k1 k2 Nothing
       _ -> fail "bad e2e params"
     where
-      kemP vr query
-        | maxVersion vr >= pqRatchetE2EEncryptVersion =
-            queryParam_ "kem_key" query
-              $>>= \k -> Just . kemParams k <$> queryParam_ "kem_ct" query
-        | otherwise = pure Nothing
+      kemP query =
+        queryParam_ "kem_key" query
+          $>>= \k -> Just . kemParams k <$> queryParam_ "kem_ct" query
       kemParams k = \case
         Nothing -> ARKP SRKSProposed $ RKParamsProposed k
         Just ct -> ARKP SRKSAccepted $ RKParamsAccepted ct k
+      adjustE2EVRange vr =
+        let v = max minSupportedE2EEncryptVersion $ minVersion vr
+        in fromMaybe vr $ safeVersionRange v (max v $ maxVersion vr)
 
 instance (RatchetKEMStateI s, AlgorithmI a) => Encoding (E2ERatchetParamsUri s a) where
   smpEncode (E2ERatchetParamsUri vr k1 k2 kem_) = smpEncode (vr, k1, k2, kem_)
@@ -403,40 +394,44 @@ instance RatchetKEMStateI s => ToField (PrivRKEMParams s) where toField = toFiel
 
 instance (Typeable s, RatchetKEMStateI s) => FromField (PrivRKEMParams s) where fromField = blobFieldDecoder smpDecode
 
+type E2EPrivRatchetParams s a = (PrivateKey a, PrivateKey a, Maybe (PrivRKEMParams s))\
+
+type RcvE2EPrivRatchetParams a = E2EPrivRatchetParams 'RKSProposed a
+
+type AE2EPrivRatchetParams a = (PrivateKey a, PrivateKey a, Maybe APrivRKEMParams)
+
 data UseKEM (s :: RatchetKEMState) where
   ProposeKEM :: UseKEM 'RKSProposed
   AcceptKEM :: KEMPublicKey -> UseKEM 'RKSAccepted
 
 data AUseKEM = forall s. RatchetKEMStateI s => AUseKEM (SRatchetKEMState s) (UseKEM s)
 
-mkRcvE2ERatchetParams :: VersionE2E -> (PrivateKey a, PrivateKey a, Maybe RcvPrivRKEMParams) -> RcvE2ERatchetParams a
+mkRcvE2ERatchetParams :: VersionE2E -> RcvE2EPrivRatchetParams a -> RcvE2ERatchetParams a
 mkRcvE2ERatchetParams v (pk1, pk2, pKem) = E2ERatchetParams v (publicKey pk1) (publicKey pk2) (mkKem <$> pKem)
   where
     mkKem :: RcvPrivRKEMParams -> RcvRKEMParams
     mkKem (PrivateRKParamsProposed (k, _)) = RKParamsProposed k
 
-generateE2EParams :: forall s a. (AlgorithmI a, DhAlgorithm a) => TVar ChaChaDRG -> VersionE2E -> Maybe (UseKEM s) -> IO (PrivateKey a, PrivateKey a, Maybe (PrivRKEMParams s), E2ERatchetParams s a)
+generateE2EParams :: forall s a. (AlgorithmI a, DhAlgorithm a) => TVar ChaChaDRG -> VersionE2E -> Maybe (UseKEM s) -> IO (E2EPrivRatchetParams s a, E2ERatchetParams s a)
 generateE2EParams g v useKEM_ = do
   (k1, pk1) <- atomically $ generateKeyPair g
   (k2, pk2) <- atomically $ generateKeyPair g
   kems <- kemParams
-  pure (pk1, pk2, snd <$> kems, E2ERatchetParams v k1 k2 (fst <$> kems))
+  pure ((pk1, pk2, snd <$> kems), E2ERatchetParams v k1 k2 (fst <$> kems))
   where
     kemParams :: IO (Maybe (RKEMParams s, PrivRKEMParams s))
     kemParams = case useKEM_ of
-      Just useKem
-        | v >= pqRatchetE2EEncryptVersion ->
-            Just <$> do
-              ks@(k, _) <- sntrup761Keypair g
-              case useKem of
-                ProposeKEM -> pure (RKParamsProposed k, PrivateRKParamsProposed ks)
-                AcceptKEM k' -> do
-                  (ct, shared) <- sntrup761Enc g k'
-                  pure (RKParamsAccepted ct k, PrivateRKParamsAccepted ct shared ks)
-      _ -> pure Nothing
+      Just useKem -> Just <$> do
+        ks@(k, _) <- sntrup761Keypair g
+        case useKem of
+          ProposeKEM -> pure (RKParamsProposed k, PrivateRKParamsProposed ks)
+          AcceptKEM k' -> do
+            (ct, shared) <- sntrup761Enc g k'
+            pure (RKParamsAccepted ct k, PrivateRKParamsAccepted ct shared ks)
+      Nothing -> pure Nothing
 
 -- used by party initiating connection, Bob in double-ratchet spec
-generateRcvE2EParams :: (AlgorithmI a, DhAlgorithm a) => TVar ChaChaDRG -> VersionE2E -> PQSupport -> IO (PrivateKey a, PrivateKey a, Maybe (PrivRKEMParams 'RKSProposed), E2ERatchetParams 'RKSProposed a)
+generateRcvE2EParams :: (AlgorithmI a, DhAlgorithm a) => TVar ChaChaDRG -> VersionE2E -> PQSupport -> IO (RcvE2EPrivRatchetParams a, RcvE2ERatchetParams a)
 generateRcvE2EParams g v = generateE2EParams g v . proposeKEM_
   where
     proposeKEM_ :: PQSupport -> Maybe (UseKEM 'RKSProposed)
@@ -445,14 +440,14 @@ generateRcvE2EParams g v = generateE2EParams g v . proposeKEM_
       PQSupportOff -> Nothing
 
 -- used by party accepting connection, Alice in double-ratchet spec
-generateSndE2EParams :: forall a. (AlgorithmI a, DhAlgorithm a) => TVar ChaChaDRG -> VersionE2E -> Maybe AUseKEM -> IO (PrivateKey a, PrivateKey a, Maybe APrivRKEMParams, AE2ERatchetParams a)
+generateSndE2EParams :: forall a. (AlgorithmI a, DhAlgorithm a) => TVar ChaChaDRG -> VersionE2E -> Maybe AUseKEM -> IO (AE2EPrivRatchetParams a, AE2ERatchetParams a)
 generateSndE2EParams g v = \case
   Nothing -> do
-    (pk1, pk2, _, e2eParams) <- generateE2EParams g v Nothing
-    pure (pk1, pk2, Nothing, AE2ERatchetParams SRKSProposed e2eParams)
+    ((pk1, pk2, _), e2eParams) <- generateE2EParams g v Nothing
+    pure ((pk1, pk2, Nothing), AE2ERatchetParams SRKSProposed e2eParams)
   Just (AUseKEM s useKEM) -> do
-    (pk1, pk2, pKem, e2eParams) <- generateE2EParams g v (Just useKEM)
-    pure (pk1, pk2, APRKP s <$> pKem, AE2ERatchetParams s e2eParams)
+    ((pk1, pk2, pKem), e2eParams) <- generateE2EParams g v (Just useKEM)
+    pure ((pk1, pk2, APRKP s <$> pKem), AE2ERatchetParams s e2eParams)
 
 data RatchetInitParams = RatchetInitParams
   { assocData :: Str,
@@ -464,32 +459,32 @@ data RatchetInitParams = RatchetInitParams
   deriving (Show)
 
 -- this is used by the peer joining the connection
-pqX3dhSnd :: DhAlgorithm a => PrivateKey a -> PrivateKey a -> Maybe APrivRKEMParams -> E2ERatchetParams 'RKSProposed a -> Either CryptoError (RatchetInitParams, Maybe KEMKeyPair)
+pqX3dhSnd :: DhAlgorithm a => AE2EPrivRatchetParams a -> E2ERatchetParams 'RKSProposed a -> Either CryptoError (RatchetInitParams, Maybe KEMKeyPair)
 --        3. replied       2. received
-pqX3dhSnd spk1 spk2 spKem_ (E2ERatchetParams v rk1 rk2 rKem_) = do
+pqX3dhSnd (spk1, spk2, spKem_) (E2ERatchetParams _ rk1 rk2 rKem_) = do
   (ks_, kem_) <- sndPq
   let initParams = pqX3dh (publicKey spk1, rk1) (dh' rk1 spk2) (dh' rk2 spk1) (dh' rk2 spk2) kem_
   pure (initParams, ks_)
   where
     sndPq :: Either CryptoError (Maybe KEMKeyPair, Maybe RatchetKEMAccepted)
     sndPq = case spKem_ of
-      Just (APRKP _ ps) | v >= pqRatchetE2EEncryptVersion -> case (ps, rKem_) of
+      Just (APRKP _ ps) -> case (ps, rKem_) of
         (PrivateRKParamsAccepted ct shared ks, Just (RKParamsProposed k)) -> Right (Just ks, Just $ RatchetKEMAccepted k shared ct)
         (PrivateRKParamsProposed ks, _) -> Right (Just ks, Nothing) -- both parties can send "proposal" in case of ratchet renegotiation
         _ -> Left CERatchetKEMState
-      _ -> Right (Nothing, Nothing)
+      Nothing -> Right (Nothing, Nothing)
 
 -- this is used by the peer that created new connection, after receiving the reply
-pqX3dhRcv :: forall s a. (RatchetKEMStateI s, DhAlgorithm a) => PrivateKey a -> PrivateKey a -> Maybe (PrivRKEMParams 'RKSProposed) -> E2ERatchetParams s a -> ExceptT CryptoError IO (RatchetInitParams, Maybe KEMKeyPair)
+pqX3dhRcv :: forall s a. (RatchetKEMStateI s, DhAlgorithm a) => RcvE2EPrivRatchetParams a -> E2ERatchetParams s a -> ExceptT CryptoError IO (RatchetInitParams, Maybe KEMKeyPair)
 --        1. sent          4. received in reply
-pqX3dhRcv rpk1 rpk2 rpKem_ (E2ERatchetParams v sk1 sk2 sKem_) = do
+pqX3dhRcv (rpk1, rpk2, rpKem_) (E2ERatchetParams _ sk1 sk2 sKem_) = do
   kem_ <- rcvPq
   let initParams = pqX3dh (sk1, publicKey rpk1) (dh' sk2 rpk1) (dh' sk1 rpk2) (dh' sk2 rpk2) (snd <$> kem_)
   pure (initParams, fst <$> kem_)
   where
     rcvPq :: ExceptT CryptoError IO (Maybe (KEMKeyPair, RatchetKEMAccepted))
     rcvPq = case sKem_ of
-      Just (RKParamsAccepted ct k') | v >= pqRatchetE2EEncryptVersion -> case rpKem_ of
+      Just (RKParamsAccepted ct k') -> case rpKem_ of
         Just (PrivateRKParamsProposed ks@(_, pk)) -> do
           shared <- liftIO $ sntrup761Dec ct pk
           pure $ Just (ks, RatchetKEMAccepted k' shared ct)
@@ -713,31 +708,22 @@ data MsgHeader a = MsgHeader
 -- to allow extension without increasing the size, the actual header length is:
 -- 69 = 2 (original size) + 2 + 1+56 (Curve448) + 4 + 4
 -- The exact size is 2288, added reserve
-paddedHeaderLen :: VersionE2E -> PQSupport -> Int
-paddedHeaderLen v = \case
-  PQSupportOn | v >= pqRatchetE2EEncryptVersion -> 2310
-  _ -> 88
+paddedHeaderLen :: PQSupport -> Int
+paddedHeaderLen = \case
+  PQSupportOn -> 2310
+  PQSupportOff -> 88
 
 -- only used in tests to validate correct padding
 -- (2 bytes - version size, 1 byte - header size)
-fullHeaderLen :: VersionE2E -> PQSupport -> Int
-fullHeaderLen v pq = 2 + 1 + paddedHeaderLen v pq + authTagSize + ivSize @AES256
+fullHeaderLen :: PQSupport -> Int
+fullHeaderLen pq = 2 + 1 + paddedHeaderLen pq + authTagSize + ivSize @AES256
 
--- pass the current version, as MsgHeader only includes the max supported version that can be different from the current
-encodeMsgHeader :: AlgorithmI a => VersionE2E -> MsgHeader a -> ByteString
-encodeMsgHeader v MsgHeader {msgMaxVersion, msgDHRs, msgKEM, msgPN, msgNs}
-  | v >= pqRatchetE2EEncryptVersion = smpEncode (msgMaxVersion, msgDHRs, msgKEM, msgPN, msgNs)
-  | otherwise = smpEncode (msgMaxVersion, msgDHRs, msgPN, msgNs)
-
--- pass the current version, as MsgHeader only includes the max supported version that can be different from the current
-msgHeaderP :: AlgorithmI a => VersionE2E -> Parser (MsgHeader a)
-msgHeaderP v = do
-  msgMaxVersion <- smpP
-  msgDHRs <- smpP
-  msgKEM <- if v >= pqRatchetE2EEncryptVersion then smpP else pure Nothing
-  msgPN <- smpP
-  msgNs <- smpP
-  pure MsgHeader {msgMaxVersion, msgDHRs, msgKEM, msgPN, msgNs}
+instance AlgorithmI a => Encoding (MsgHeader a) where
+  smpEncode MsgHeader {msgMaxVersion, msgDHRs, msgKEM, msgPN, msgNs} =
+    smpEncode (msgMaxVersion, msgDHRs, msgKEM, msgPN, msgNs)
+  smpP = do
+    (msgMaxVersion, msgDHRs, msgKEM, msgPN, msgNs) <- smpP
+    pure MsgHeader {msgMaxVersion, msgDHRs, msgKEM, msgPN, msgNs}
 
 data EncMessageHeader = EncMessageHeader
   { ehVersion :: VersionE2E, -- this is current ratchet version
@@ -749,26 +735,11 @@ data EncMessageHeader = EncMessageHeader
 -- this encoding depends on version in EncMessageHeader because it is "current" ratchet version
 instance Encoding EncMessageHeader where
   smpEncode EncMessageHeader {ehVersion, ehIV, ehAuthTag, ehBody} =
-    smpEncode (ehVersion, ehIV, ehAuthTag) <> encodeLarge ehVersion ehBody
+    smpEncode (ehVersion, ehIV, ehAuthTag, Large ehBody)
   smpP = do
-    (ehVersion, ehIV, ehAuthTag) <- smpP
-    ehBody <- largeP
+    (ehVersion, ehIV, ehAuthTag, Large ehBody) <- smpP
     pure EncMessageHeader {ehVersion, ehIV, ehAuthTag, ehBody}
 
--- the encoder always uses 2-byte lengths for the new version, even for short headers without PQ keys.
-encodeLarge :: VersionE2E -> ByteString -> ByteString
-encodeLarge v s
-  | v >= pqRatchetE2EEncryptVersion = smpEncode $ Large s
-  | otherwise = smpEncode s
-
--- This parser relies on the fact that header cannot be shorter than 32 bytes (it is ~69 bytes without PQ KEM),
--- therefore if the first byte is less or equal to 31 (x1F), then we have 2 byte-length limited to 8191.
--- This allows upgrading the current version in one message.
-largeP :: Parser ByteString
-largeP = do
-  len1 <- peekWord8'
-  if len1 < 32 then unLarge <$> smpP else smpP
-
 -- the header is length-prefixed to parse it as string and use as part of associated data for authenticated encryption
 data EncRatchetMessage = EncRatchetMessage
   { emHeader :: ByteString,
@@ -776,15 +747,12 @@ data EncRatchetMessage = EncRatchetMessage
     emBody :: ByteString
   }
 
-encodeEncRatchetMessage :: VersionE2E -> EncRatchetMessage -> ByteString
-encodeEncRatchetMessage v EncRatchetMessage {emHeader, emBody, emAuthTag} =
-  encodeLarge v emHeader <> smpEncode (emAuthTag, Tail emBody)
-
-encRatchetMessageP :: Parser EncRatchetMessage
-encRatchetMessageP = do
-  emHeader <- largeP
-  (emAuthTag, Tail emBody) <- smpP
-  pure EncRatchetMessage {emHeader, emBody, emAuthTag}
+instance Encoding EncRatchetMessage where
+  smpEncode EncRatchetMessage {emHeader, emBody, emAuthTag} =
+    smpEncode (Large emHeader, emAuthTag, Tail emBody)
+  smpP = do
+    (Large emHeader, emAuthTag, Tail emBody) <- smpP
+    pure EncRatchetMessage {emHeader, emBody, emAuthTag}
 
 newtype PQEncryption = PQEncryption {enablePQ :: Bool}
   deriving (Eq, Show)
@@ -833,15 +801,15 @@ pqEncToSupport (PQEncryption pq) = PQSupport pq
 pqSupportAnd :: PQSupport -> PQSupport -> PQSupport
 pqSupportAnd (PQSupport s1) (PQSupport s2) = PQSupport $ s1 && s2
 
-pqEnableSupport :: VersionE2E -> PQSupport -> PQEncryption -> PQSupport
-pqEnableSupport v (PQSupport sup) (PQEncryption enc) = PQSupport $ sup || (v >= pqRatchetE2EEncryptVersion && enc)
+pqEnableSupport :: PQSupport -> PQEncryption -> PQSupport
+pqEnableSupport (PQSupport sup) (PQEncryption enc) = PQSupport $ sup || enc
 
-replyKEM_ :: VersionE2E -> Maybe (RKEMParams 'RKSProposed) -> PQSupport -> Maybe AUseKEM
-replyKEM_ v kem_ = \case
-  PQSupportOn | v >= pqRatchetE2EEncryptVersion -> Just $ case kem_ of
+replyKEM_ :: Maybe (RKEMParams 'RKSProposed) -> PQSupport -> Maybe AUseKEM
+replyKEM_ kem_ = \case
+  PQSupportOn -> Just $ case kem_ of
     Just (RKParamsProposed k) -> AUseKEM SRKSAccepted $ AcceptKEM k
     Nothing -> AUseKEM SRKSProposed ProposeKEM
-  _ -> Nothing
+  PQSupportOff -> Nothing
 
 instance StrEncoding PQEncryption where
   strEncode pqMode
@@ -890,9 +858,9 @@ connPQEncryption = \case
   IKUsePQ -> PQSupportOn
   IKLinkPQ pq -> pq -- default for creating connection is IKLinkPQ PQEncOn
 
-joinContactInitialKeys :: Bool -> PQSupport -> InitialKeys
-joinContactInitialKeys pqCompatible = \case
-  PQSupportOn | pqCompatible -> IKUsePQ
+joinContactInitialKeys :: PQSupport -> InitialKeys
+joinContactInitialKeys = \case
+  PQSupportOn -> IKUsePQ
   pqEnc -> IKLinkPQ pqEnc
 
 rcCheckCanPad :: Int -> ByteString -> ExceptT CryptoError IO ()
@@ -908,14 +876,14 @@ rcEncryptHeader rc@Ratchet {rcSnd = Just sr@SndRatchet {rcCKs, rcHKs}, rcDHRs, r
       -- PQ encryption can be enabled or disabled
       rcEnableKEM' = fromMaybe rcEnableKEM pqEnc_
       -- support for PQ encryption (and therefore large headers/small envelopes) can only be enabled, it cannot be disabled
-      rcSupportKEM' = pqEnableSupport v rcSupportKEM rcEnableKEM'
+      rcSupportKEM' = pqEnableSupport rcSupportKEM rcEnableKEM'
       -- This sets max version to support PQ encryption.
       -- Current version upgrade happens when peer decrypts the message.
       -- TODO note that maxSupported will not downgrade here below current (v).
-      maxSupported' = max supportedE2EVersion $ if pqEnc_ == Just PQEncOn then pqRatchetE2EEncryptVersion else v
+      maxSupported' = max supportedE2EVersion $ if pqEnc_ == Just PQEncOn then minSupportedE2EEncryptVersion else v
       rcVersion' = rcVersion {maxSupported = maxSupported'}
   -- enc_header = HENCRYPT(state.HKs, header)
-  (ehAuthTag, ehBody) <- encryptAEAD rcHKs ehIV (paddedHeaderLen v rcSupportKEM') rcAD (msgHeader v maxSupported')
+  (ehAuthTag, ehBody) <- encryptAEAD rcHKs ehIV (paddedHeaderLen rcSupportKEM') rcAD (msgHeader maxSupported')
   -- return enc_header
   let emHeader = smpEncode EncMessageHeader {ehVersion = v, ehBody, ehAuthTag, ehIV}
       msgEncryptKey =
@@ -943,9 +911,8 @@ rcEncryptHeader rc@Ratchet {rcSnd = Just sr@SndRatchet {rcCKs, rcHKs}, rcDHRs, r
     --   pn = state.PN,
     --   n = state.Ns
     -- )
-    msgHeader v maxSupported' =
-      encodeMsgHeader
-        v
+    msgHeader maxSupported' =
+      smpEncode
         MsgHeader
           { msgMaxVersion = maxSupported',
             msgDHRs = publicKey rcDHRs,
@@ -968,11 +935,10 @@ data MsgEncryptKey a = MsgEncryptKey
   deriving (Show)
 
 rcEncryptMsg :: AlgorithmI a => MsgEncryptKey a -> Int -> ByteString -> ExceptT CryptoError IO ByteString
-rcEncryptMsg MsgEncryptKey {msgKey = MessageKey mk iv, msgRcAD, msgEncHeader, msgRcVersion = v} paddedMsgLen msg = do
+rcEncryptMsg MsgEncryptKey {msgKey = MessageKey mk iv, msgRcAD, msgEncHeader} paddedMsgLen msg = do
   -- return ENCRYPT(mk, plaintext, CONCAT(AD, enc_header))
   (emAuthTag, emBody) <- encryptAEAD mk iv paddedMsgLen (msgRcAD <> msgEncHeader) msg
-  let msg' = encodeEncRatchetMessage v EncRatchetMessage {emHeader = msgEncHeader, emBody, emAuthTag}
-  pure msg'
+  pure $ smpEncode EncRatchetMessage {emHeader = msgEncHeader, emBody, emAuthTag}
 
 data SkippedMessage a
   = SMMessage (DecryptResult a)
@@ -996,7 +962,7 @@ rcDecrypt ::
   ByteString ->
   ExceptT CryptoError IO (DecryptResult a)
 rcDecrypt g rc@Ratchet {rcRcv, rcAD = Str rcAD, rcVersion} rcMKSkipped msg' = do
-  encMsg@EncRatchetMessage {emHeader} <- parseE CryptoHeaderError encRatchetMessageP msg'
+  encMsg@EncRatchetMessage {emHeader} <- parseE CryptoHeaderError smpP msg'
   encHdr <- parseE CryptoHeaderError smpP emHeader
   -- plaintext = TrySkippedMessageKeysHE(state, enc_header, cipher-text, AD)
   decryptSkipped encHdr encMsg >>= \case
@@ -1041,7 +1007,7 @@ rcDecrypt g rc@Ratchet {rcRcv, rcAD = Str rcAD, rcVersion} rcMKSkipped msg' = do
         smkDiff :: SkippedMsgKeys -> SkippedMsgDiff
         smkDiff smks = if M.null smks then SMDNoChange else SMDAdd smks
         ratchetStep :: Ratchet a -> MsgHeader a -> ExceptT CryptoError IO (Ratchet a)
-        ratchetStep rc'@Ratchet {rcDHRs, rcRK, rcNHKs, rcNHKr, rcSupportKEM, rcVersion = rv} MsgHeader {msgDHRs, msgKEM} = do
+        ratchetStep rc'@Ratchet {rcDHRs, rcRK, rcNHKs, rcNHKr, rcSupportKEM} MsgHeader {msgDHRs, msgKEM} = do
           (kemSS, kemSS', rcKEM') <- pqRatchetStep rc' msgKEM
           -- state.DHRs = GENERATE_DH()
           (_, rcDHRs') <- atomically $ generateKeyPair @a g
@@ -1056,7 +1022,7 @@ rcDecrypt g rc@Ratchet {rcRcv, rcAD = Str rcAD, rcVersion} rcMKSkipped msg' = do
             rc'
               { rcDHRs = rcDHRs',
                 rcKEM = rcKEM',
-                rcSupportKEM = pqEnableSupport (current rv) rcSupportKEM rcEnableKEM',
+                rcSupportKEM = pqEnableSupport rcSupportKEM rcEnableKEM',
                 rcEnableKEM = rcEnableKEM',
                 rcSndKEM = PQEncryption sndKEM,
                 rcRcvKEM = PQEncryption rcvKEM,
@@ -1070,17 +1036,17 @@ rcDecrypt g rc@Ratchet {rcRcv, rcAD = Str rcAD, rcVersion} rcMKSkipped msg' = do
                 rcNHKr = rcNHKr'
               }
         pqRatchetStep :: Ratchet a -> Maybe ARKEMParams -> ExceptT CryptoError IO (Maybe KEMSharedKey, Maybe KEMSharedKey, Maybe RatchetKEM)
-        pqRatchetStep Ratchet {rcKEM, rcEnableKEM = PQEncryption pqEnc, rcVersion = rv} = \case
+        pqRatchetStep Ratchet {rcKEM, rcEnableKEM = PQEncryption pqEnc} = \case
           -- received message does not have KEM in header,
           -- but the user enabled KEM when sending previous message
           Nothing -> case rcKEM of
-            Nothing | pqEnc && current rv >= pqRatchetE2EEncryptVersion -> do
+            Nothing | pqEnc -> do
               rcPQRs <- liftIO $ sntrup761Keypair g
               pure (Nothing, Nothing, Just RatchetKEM {rcPQRs, rcKEMs = Nothing})
             _ -> pure (Nothing, Nothing, Nothing)
           -- received message has KEM in header.
           Just (ARKP _ ps)
-            | pqEnc && current rv >= pqRatchetE2EEncryptVersion -> do
+            | pqEnc -> do
                 -- state.PQRr = header.kem
                 (ss, rcPQRr) <- sharedSecret
                 -- state.PQRct = PQKEM-ENC(state.PQRr, state.PQRss) // encapsulated additional shared secret KEM #1
@@ -1148,9 +1114,9 @@ rcDecrypt g rc@Ratchet {rcRcv, rcAD = Str rcAD, rcVersion} rcMKSkipped msg' = do
         e -> throwE e
     -- header = HDECRYPT(state.NHKr, enc_header)
     decryptNextHeader hdr = (AdvanceRatchet,) <$> decryptHeader (rcNHKr rc) hdr
-    decryptHeader k EncMessageHeader {ehVersion, ehBody, ehAuthTag, ehIV} = do
+    decryptHeader k EncMessageHeader {ehBody, ehAuthTag, ehIV} = do
       header <- decryptAEAD k ehIV rcAD ehBody ehAuthTag `catchE` \_ -> throwE CERatchetHeader
-      parseE' CryptoHeaderError (msgHeaderP ehVersion) header
+      parseE' CryptoHeaderError smpP header
     decryptMessage :: MessageKey -> EncRatchetMessage -> ExceptT CryptoError IO (Either CryptoError ByteString)
     decryptMessage (MessageKey mk iv) EncRatchetMessage {emHeader, emBody, emAuthTag} =
       -- DECRYPT(mk, cipher-text, CONCAT(AD, enc_header))

src/Simplex/Messaging/Crypto/SNTRUP761/Bindings.hs

@@ -1,11 +1,14 @@
 {-# LANGUAGE CPP #-}
 {-# LANGUAGE TypeApplications #-}
+{-# LANGUAGE PatternSynonyms #-}
 
 module Simplex.Messaging.Crypto.SNTRUP761.Bindings
-  ( KEMPublicKey (..),
+  ( KEMPublicKey,
     KEMSecretKey,
-    KEMCiphertext (..),
-    KEMSharedKey (..),
+    KEMCiphertext,
+    KEMSharedKey,
+    pattern KEMPublicKey,
+    pattern KEMSharedKey,
     KEMKeyPair,
     sntrup761Keypair,
     sntrup761Enc,
@@ -25,8 +28,9 @@ import Simplex.Messaging.Crypto.SNTRUP761.Bindings.FFI
 import Simplex.Messaging.Crypto.SNTRUP761.Bindings.RNG (rngFuncPtr, withDRG)
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
+import Simplex.Messaging.Util ((<$?>))
 
-newtype KEMPublicKey = KEMPublicKey ByteString
+newtype KEMPublicKey = KEMPublicKey_ ByteString
   deriving (Eq, Show)
 
 newtype KEMSecretKey = KEMSecretKey ScrubbedBytes
@@ -35,18 +39,24 @@ newtype KEMSecretKey = KEMSecretKey ScrubbedBytes
 newtype KEMCiphertext = KEMCiphertext ByteString
   deriving (Eq, Show)
 
-newtype KEMSharedKey = KEMSharedKey ScrubbedBytes
+newtype KEMSharedKey = KEMSharedKey_ ScrubbedBytes
   deriving (Eq, Show)
 
-unsafeRevealKEMSharedKey :: KEMSharedKey -> String
-unsafeRevealKEMSharedKey (KEMSharedKey scrubbed) = show (BA.convert scrubbed :: ByteString)
-{-# DEPRECATED unsafeRevealKEMSharedKey "unsafeRevealKEMSharedKey left in code" #-}
+pattern KEMPublicKey :: ByteString -> KEMPublicKey
+pattern KEMPublicKey s <- KEMPublicKey_ s
+
+pattern KEMSharedKey :: ScrubbedBytes -> KEMSharedKey
+pattern KEMSharedKey s <- KEMSharedKey_ s
+
+{-# COMPLETE KEMPublicKey #-}
+
+{-# COMPLETE KEMSharedKey #-}
 
 type KEMKeyPair = (KEMPublicKey, KEMSecretKey)
 
 sntrup761Keypair :: TVar ChaChaDRG -> IO KEMKeyPair
 sntrup761Keypair drg =
-  bimap KEMPublicKey KEMSecretKey
+  bimap KEMPublicKey_ KEMSecretKey
     <$> BA.allocRet
       c_SNTRUP761_SECRETKEY_SIZE
       ( \skPtr ->
@@ -57,7 +67,7 @@ sntrup761Keypair drg =
 sntrup761Enc :: TVar ChaChaDRG -> KEMPublicKey -> IO (KEMCiphertext, KEMSharedKey)
 sntrup761Enc drg (KEMPublicKey pk) =
   BA.withByteArray pk $ \pkPtr ->
-    bimap KEMCiphertext KEMSharedKey
+    bimap KEMCiphertext KEMSharedKey_
       <$> BA.allocRet
         c_SNTRUP761_SIZE
         ( \kPtr ->
@@ -69,40 +79,47 @@ sntrup761Dec :: KEMCiphertext -> KEMSecretKey -> IO KEMSharedKey
 sntrup761Dec (KEMCiphertext c) (KEMSecretKey sk) =
   BA.withByteArray sk $ \skPtr ->
     BA.withByteArray c $ \cPtr ->
-      KEMSharedKey
+      KEMSharedKey_
         <$> BA.alloc c_SNTRUP761_SIZE (\kPtr -> c_sntrup761_dec kPtr cPtr skPtr)
 
+parseKey :: BA.ByteArrayAccess bs => (bs -> key) -> String -> Int -> bs -> Either String key
+parseKey kCon name expected s
+  | len == expected = Right $ kCon s
+  | otherwise = Left $ name <> " must be " <> show expected <> " bytes, got " <> show len
+  where
+    len = BA.length s    
+
 instance Encoding KEMSecretKey where
   smpEncode (KEMSecretKey c) = smpEncode . Large $ BA.convert c
-  smpP = KEMSecretKey . BA.convert . unLarge <$> smpP
+  smpP = parseKey KEMSecretKey "SNTRUP761 secret key" c_SNTRUP761_SECRETKEY_SIZE . BA.convert . unLarge <$?> smpP
 
 instance StrEncoding KEMSecretKey where
   strEncode (KEMSecretKey pk) = strEncode (BA.convert pk :: ByteString)
-  strP = KEMSecretKey . BA.convert <$> strP @ByteString
+  strP = parseKey KEMSecretKey "SNTRUP761 secret key" c_SNTRUP761_SECRETKEY_SIZE . BA.convert <$?> strP @ByteString
 
 instance Encoding KEMPublicKey where
   smpEncode (KEMPublicKey pk) = smpEncode . Large $ BA.convert pk
-  smpP = KEMPublicKey . BA.convert . unLarge <$> smpP
+  smpP = parseKey KEMPublicKey_ "SNTRUP761 public key" c_SNTRUP761_PUBLICKEY_SIZE . unLarge <$?> smpP
 
 instance StrEncoding KEMPublicKey where
   strEncode (KEMPublicKey pk) = strEncode (BA.convert pk :: ByteString)
-  strP = KEMPublicKey . BA.convert <$> strP @ByteString
+  strP = parseKey KEMPublicKey_ "SNTRUP761 public key" c_SNTRUP761_PUBLICKEY_SIZE <$?> strP @ByteString
 
 instance Encoding KEMCiphertext where
   smpEncode (KEMCiphertext c) = smpEncode . Large $ BA.convert c
-  smpP = KEMCiphertext . BA.convert . unLarge <$> smpP
+  smpP = parseKey KEMCiphertext "SNTRUP761 ciphertext" c_SNTRUP761_CIPHERTEXT_SIZE . unLarge <$?> smpP
 
 instance Encoding KEMSharedKey where
   smpEncode (KEMSharedKey c) = smpEncode (BA.convert c :: ByteString)
-  smpP = KEMSharedKey . BA.convert <$> smpP @ByteString
+  smpP = KEMSharedKey_ . BA.convert <$> smpP @ByteString
 
 instance StrEncoding KEMCiphertext where
   strEncode (KEMCiphertext pk) = strEncode (BA.convert pk :: ByteString)
-  strP = KEMCiphertext . BA.convert <$> strP @ByteString
+  strP = parseKey KEMCiphertext "SNTRUP761 ciphertext" c_SNTRUP761_CIPHERTEXT_SIZE <$?> strP @ByteString
 
 instance StrEncoding KEMSharedKey where
   strEncode (KEMSharedKey pk) = strEncode (BA.convert pk :: ByteString)
-  strP = KEMSharedKey . BA.convert <$> strP @ByteString
+  strP = KEMSharedKey_ . BA.convert <$> strP @ByteString
 
 instance ToJSON KEMSecretKey where
   toJSON = strToJSON
@@ -130,9 +147,9 @@ instance ToField KEMSharedKey where
 
 instance FromField KEMSharedKey where
 #if defined(dbPostgres)
-  fromField f dat = KEMSharedKey . BA.convert @ByteString <$> fromField f dat
+  fromField f dat = KEMSharedKey_ . BA.convert @ByteString <$> fromField f dat
 #else
-  fromField f = KEMSharedKey . BA.convert @ByteString <$> fromField f
+  fromField f = KEMSharedKey_ . BA.convert @ByteString <$> fromField f
 #endif
 
 instance ToJSON KEMSharedKey where

src/Simplex/Messaging/Crypto/ShortLink.hs

@@ -53,14 +53,14 @@ invShortLinkKdf :: LinkKey -> C.SbKey
 invShortLinkKdf (LinkKey k) = C.unsafeSbKey $ C.hkdf "" k "SimpleXInvLink" 32
 
 encodeSignLinkData :: forall c. ConnectionModeI c => C.KeyPairEd25519 -> VersionRangeSMPA -> ConnectionRequestUri c -> Maybe ByteString -> UserConnLinkData c -> (LinkKey, (ByteString, ByteString))
-encodeSignLinkData keys@(_, pk) agentVRange linkConnReq linkEntityId userData =
-  let (linkKey, fd) = encodeSignFixedData keys agentVRange linkConnReq linkEntityId
+encodeSignLinkData keys@(_, pk) agentVRange connReq linkEntityId userData =
+  let (linkKey, fd) = encodeSignFixedData keys agentVRange connReq linkEntityId
       md = encodeSignUserData (sConnectionMode @c) pk agentVRange userData
    in (linkKey, (fd, md))
 
 encodeSignFixedData :: ConnectionModeI c => C.KeyPairEd25519 -> VersionRangeSMPA -> ConnectionRequestUri c -> Maybe ByteString -> (LinkKey, ByteString)
-encodeSignFixedData (rootKey, pk) agentVRange linkConnReq linkEntityId =
-  let fd = smpEncode FixedLinkData {agentVRange, rootKey, linkConnReq, linkEntityId}
+encodeSignFixedData (rootKey, pk) agentVRange connReq linkEntityId =
+  let fd = smpEncode FixedLinkData {agentVRange, rootKey, linkConnReq = binaryConnReq connReq, linkEntityId}
    in (LinkKey (C.sha3_256 fd), encodeSign pk fd)
 
 encodeSignUserData :: ConnectionModeI c => SConnectionMode c -> C.PrivateKeyEd25519 -> VersionRangeSMPA -> UserConnLinkData c -> ByteString
@@ -120,6 +120,6 @@ decryptLinkData linkKey k (encFD, encMD) = do
       pure (sig, s)
     decode :: Encoding a => ByteString -> Either AgentErrorType a
     decode = msgErr . smpDecode
-    msgErr = first (const $ AGENT A_MESSAGE)
+    msgErr = first (const $ AGENT $ A_MESSAGE "parse link data")
     linkErr :: String -> Either AgentErrorType ()
     linkErr = Left . AGENT . A_LINK

src/Simplex/Messaging/Encoding.hs

@@ -11,6 +11,7 @@ module Simplex.Messaging.Encoding
   ( Encoding (..),
     Tail (..),
     Large (..),
+    EncList (..),
     _smpP,
     smpEncodeList,
     smpListP,
@@ -177,6 +178,12 @@ instance Encoding a => Encoding (L.NonEmpty a) where
       0 -> fail "empty list"
       n -> L.fromList <$> A.count n smpP
 
+newtype EncList a = EncList [a]
+
+instance Encoding a => Encoding (EncList a) where
+  smpEncode (EncList xs) = smpEncodeList xs
+  smpP = EncList <$> smpListP
+
 instance (Encoding a, Encoding b) => Encoding (a, b) where
   smpEncode (a, b) = smpEncode a <> smpEncode b
   {-# INLINE smpEncode #-}

src/Simplex/Messaging/Encoding/String.hs

@@ -1,10 +1,14 @@
+{-# LANGUAGE DataKinds #-}
 {-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE KindSignatures #-}
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE ScopedTypeVariables #-}
 
 module Simplex.Messaging.Encoding.String
   ( TextEncoding (..),
     StrEncoding (..),
     Str (..),
+    StrJSON (..),
     strP_,
     _strP,
     strToJSON,
@@ -34,6 +38,7 @@ import Data.Int (Int64)
 import Data.IntSet (IntSet)
 import qualified Data.IntSet as IS
 import qualified Data.List.NonEmpty as L
+import Data.Proxy (Proxy (..))
 import Data.Set (Set)
 import qualified Data.Set as S
 import Data.Text (Text)
@@ -44,6 +49,7 @@ import Data.Time.Format.ISO8601
 import Data.Word (Word16, Word32)
 import qualified Data.X509 as X
 import qualified Data.X509.Validation as XV
+import GHC.TypeLits (KnownSymbol, Symbol, symbolVal)
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Parsers (parseAll)
 import Simplex.Messaging.Util (bshow, safeDecodeUtf8, (<$?>))
@@ -247,3 +253,21 @@ textToEncoding = JE.text . textEncode
 
 textParseJSON :: TextEncoding a => String -> J.Value -> JT.Parser a
 textParseJSON name = J.withText name $ maybe (fail name) pure . textDecode
+
+-- | Derives ToJSON/FromJSON from the wrapped type's own StrEncoding (a base64url
+-- string), so any validation that StrEncoding performs (e.g. length) also applies
+-- to JSON parsing. The @name@ symbol is the parse error label. The type parameter
+-- @a@ is essential: it makes parseJSON resolve at the wrapped type rather than at
+-- ByteString. Use via DerivingVia, e.g.:
+--
+-- > newtype Key = Key ByteString
+-- >   deriving (ToJSON, FromJSON) via (StrJSON "Key" Key)
+newtype StrJSON (name :: Symbol) a = StrJSON {unStrJSON :: a}
+  deriving (Eq, Show)
+
+instance StrEncoding a => ToJSON (StrJSON name a) where
+  toJSON (StrJSON a) = strToJSON a
+  toEncoding (StrJSON a) = strToJEncoding a
+
+instance forall name a. (KnownSymbol name, StrEncoding a) => FromJSON (StrJSON name a) where
+  parseJSON = fmap StrJSON . strParseJSON (symbolVal (Proxy :: Proxy name))

src/Simplex/Messaging/Names/Record.hs

@@ -0,0 +1,46 @@
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE StrictData #-}
+{-# LANGUAGE TemplateHaskell #-}
+
+module Simplex.Messaging.Names.Record
+  ( NameRecord (..),
+  )
+where
+
+import qualified Data.Aeson as J
+import qualified Data.Aeson.TH as JQ
+import Data.Text (Text)
+import Simplex.Messaging.Parsers (defaultJSON, dropPrefix)
+
+-- | Resolved name record returned by the names role. JSON keys match the
+--   resolver REST output; both FromJSON (resolver -> server) and ToJSON
+--   (server diagnostics) are TH-derived from one Options value, so the Haskell
+--   type IS the schema. Text fields use the empty string as the "unset"
+--   sentinel; coin fields use JSON null. simplexContact / simplexChannel are
+--   arrays of links (primary first, empty when unset) so a name can advertise
+--   fallback SMP servers. owner / resolver are 0x-hex Ethereum addresses, kept
+--   verbatim as text (the resolver is the source of truth for their validity).
+--   The only size bound is the SMP transport block (enforced by the framing).
+data NameRecord = NameRecord
+  { nrName :: Text,
+    nrNickname :: Text,
+    nrWebsite :: Text,
+    nrLocation :: Text,
+    nrSimplexContact :: [Text],
+    nrSimplexChannel :: [Text],
+    nrEth :: Maybe Text,
+    nrBtc :: Maybe Text,
+    nrXmr :: Maybe Text,
+    nrDot :: Maybe Text,
+    nrOwner :: Text,
+    nrResolver :: Text -- resolver address (0x hex) that produced the record
+  }
+  deriving (Eq, Show)
+
+-- omitNothingFields False so absent coin fields surface as JSON null (matches
+-- the resolver output for unset coins).
+$( JQ.deriveJSON
+    defaultJSON {J.omitNothingFields = False, J.fieldLabelModifier = dropPrefix "nr"}
+    ''NameRecord
+ )

src/Simplex/Messaging/Notifications/Protocol.hs

@@ -61,7 +61,7 @@ import Simplex.Messaging.Agent.Store.DB (FromField (..), ToField (..), fromTextF
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
-import Simplex.Messaging.Notifications.Transport (NTFVersion, invalidReasonNTFVersion, ntfClientHandshake)
+import Simplex.Messaging.Notifications.Transport (NTFVersion, ntfClientHandshake)
 import Simplex.Messaging.Protocol hiding (Command (..), CommandTag (..))
 import Simplex.Messaging.Util (eitherToMaybe, (<$?>))
 
@@ -329,18 +329,12 @@ data NtfResponse
 
 instance ProtocolEncoding NTFVersion ErrorType NtfResponse where
   type Tag NtfResponse = NtfResponseTag
-  encodeProtocol v = \case
+  encodeProtocol _v = \case
     NRTknId entId dhKey -> e (NRTknId_, ' ', entId, dhKey)
     NRSubId entId -> e (NRSubId_, ' ', entId)
     NROk -> e NROk_
     NRErr err -> e (NRErr_, ' ', err)
-    NRTkn stat -> e (NRTkn_, ' ', stat')
-      where
-        stat'
-          | v >= invalidReasonNTFVersion = stat
-          | otherwise = case stat of
-              NTInvalid _ -> NTInvalid Nothing
-              _ -> stat
+    NRTkn stat -> e (NRTkn_, ' ', stat)
     NRSub stat -> e (NRSub_, ' ', stat)
     NRPong -> e NRPong_
     where

src/Simplex/Messaging/Notifications/Server.hs

@@ -34,6 +34,7 @@ import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
 import Data.Either (partitionEithers)
 import Data.Functor (($>))
+import Data.Hashable (hash)
 import Data.IORef
 import Data.Int (Int64)
 import qualified Data.IntSet as IS
@@ -526,10 +527,10 @@ subscribeNtfs NtfSubscriber {smpSubscribers, subscriberSeq, smpAgent = ca} st sm
       subscribeQueuesNtfs ca smpServer' [sub]
 
 ntfSubscriber :: NtfSubscriber -> M ()
-ntfSubscriber NtfSubscriber {smpAgent = ca@SMPClientAgent {msgQ, agentQ}} =
+ntfSubscriber NtfSubscriber {smpAgent = ca@SMPClientAgent {msgQ = msgQ_, agentQ}} =
   race_ receiveSMP receiveAgent
   where
-    receiveSMP = do
+    receiveSMP = forM_ msgQ_ $ \msgQ -> do
       st <- asks store
       ps <- asks pushServer
       stats <- asks serverStats
@@ -640,20 +641,36 @@ showServer' :: SMPServer -> Text
 showServer' = decodeLatin1 . strEncode . host
 
 pushNotification :: NtfPushServer -> Maybe T.Text -> OwnServer -> NtfTknRec -> PushNotification -> M ()
-pushNotification s srvHost_ isOwn tkn@NtfTknRec {token = DeviceToken pp _} ntf = do
-  q <- getOrCreatePushWorker s (srvHost_, pp) isOwn
-  atomically $ writeTBQueue q (tkn, ntf)
+pushNotification s srvHost_ isOwn tkn@NtfTknRec {ntfTknId, token = token@(DeviceToken pp _)} ntf =
+  ifM
+    (pushProviderAllowed token)
+    (getOrCreatePushWorker s (srvHost_, pp, hash (unEntityId ntfTknId) `mod` pushWorkersPerServer) isOwn >>= atomically . (`writeTBQueue` (tkn, ntf)))
+    (logWarn "skipping disabled APNS test push provider")
+  where
+    pushWorkersPerServer = 8
 
-getOrCreatePushWorker :: NtfPushServer -> (Maybe T.Text, PushProvider) -> OwnServer -> M (TBQueue (NtfTknRec, PushNotification))
-getOrCreatePushWorker s@NtfPushServer {pushWorkers, pushWorkerSeq, pushQSize} key@(srvHost_, _) isOwn = do
+pushProviderAllowed :: DeviceToken -> M Bool
+pushProviderAllowed (DeviceToken PPApnsTest _) = asks (allowTestPushProvider . config)
+pushProviderAllowed _ = pure True
+
+guardPushProvider :: DeviceToken -> M NtfResponse -> M NtfResponse
+guardPushProvider token action =
+  ifM
+    (pushProviderAllowed token)
+    action
+    (pure $ NRErr $ CMD SMP.PROHIBITED)
+
+getOrCreatePushWorker :: NtfPushServer -> (Maybe T.Text, PushProvider, Int) -> OwnServer -> M (TBQueue (NtfTknRec, PushNotification))
+getOrCreatePushWorker s@NtfPushServer {pushWorkers, pushWorkerSeq, pushQSize} key@(srvHost_, _, _) isOwn = do
   ts <- liftIO getCurrentTime
-  atomically (getSessVar pushWorkerSeq key pushWorkers ts) >>= \case
-    Left v -> do
+  withGetSessVar' pushWorkerSeq key pushWorkers ts createWorker existingWorker
+  where
+    createWorker v = do
       q <- liftIO $ newTBQueueIO pushQSize
       tId <- mkWeakThreadId =<< forkIO (runPushWorker s srvHost_ isOwn q)
       atomically $ putTMVar (sessionVar v) PushWorker {workerQ = q, workerThreadId = tId}
       pure q
-    Right v -> workerQ <$> atomically (readTMVar $ sessionVar v)
+    existingWorker v = workerQ <$> atomically (readTMVar $ sessionVar v)
 
 runPushWorker :: NtfPushServer -> Maybe T.Text -> OwnServer -> TBQueue (NtfTknRec, PushNotification) -> M ()
 runPushWorker s srvHost_ isOwn q = forever $ do
@@ -717,7 +734,7 @@ runPushWorker s srvHost_ isOwn q = forever $ do
               _ -> err e
         err e = logError ("Push provider error (" <> tshow pp <> ", " <> tshow ntfTknId <> "): " <> tshow e) $> Left e
 
-pushWorkersQLength :: TMap (Maybe T.Text, PushProvider) PushWorkerVar -> IO Natural
+pushWorkersQLength :: TMap (Maybe T.Text, PushProvider, Int) PushWorkerVar -> IO Natural
 pushWorkersQLength workers = do
   ws <- readTVarIO workers
   foldM addQLength 0 ws
@@ -834,7 +851,7 @@ client NtfServerClient {rcvQ, sndQ} ns@NtfSubscriber {smpAgent = ca} ps =
   where
     processCommand :: NtfRequest -> M (Transmission NtfResponse)
     processCommand = \case
-      NtfReqNew corrId (ANE SToken newTkn@(NewNtfTkn token _ dhPubKey)) -> (corrId,NoEntity,) <$> do
+      NtfReqNew corrId (ANE SToken newTkn@(NewNtfTkn token _ dhPubKey)) -> (corrId,NoEntity,) <$> guardPushProvider token (do
         logDebug "TNEW - new token"
         (srvDhPubKey, srvDhPrivKey) <- atomically . C.generateKeyPair =<< asks random
         let dhSecret = C.dh' dhPubKey srvDhPrivKey
@@ -846,10 +863,10 @@ client NtfServerClient {rcvQ, sndQ} ns@NtfSubscriber {smpAgent = ca} ps =
           pushNotification ps Nothing False tkn $ PNVerification regCode
           incNtfStatT token ntfVrfQueued
           incNtfStatT token tknCreated
-          pure $ NRTknId tknId srvDhPubKey
+          pure $ NRTknId tknId srvDhPubKey)
       NtfReqCmd SToken (NtfTkn tkn@NtfTknRec {token, ntfTknId, tknStatus, tknRegCode, tknDhSecret, tknDhPrivKey}) (corrId, tknId, cmd) -> do
         (corrId,tknId,) <$> case cmd of
-          TNEW (NewNtfTkn _ _ dhPubKey) -> do
+          TNEW (NewNtfTkn _ _ dhPubKey) -> guardPushProvider token $ do
             logDebug "TNEW - registered token"
             let dhSecret = C.dh' dhPubKey tknDhPrivKey
             -- it is required that DH secret is the same, to avoid failed verifications if notification is delaying
@@ -872,7 +889,7 @@ client NtfServerClient {rcvQ, sndQ} ns@NtfSubscriber {smpAgent = ca} ps =
           TCHK -> do
             logDebug "TCHK"
             pure $ NRTkn tknStatus
-          TRPL token' -> do
+          TRPL token' -> guardPushProvider token' $ do
             logDebug "TRPL - replace token"
             regCode <- getRegCode
             let tkn' = tkn {token = token', tknStatus = NTRegistered, tknRegCode = regCode}

src/Simplex/Messaging/Notifications/Server/Env.hs

@@ -81,6 +81,7 @@ data NtfServerConfig = NtfServerConfig
     pushQSize :: Natural,
     smpAgentCfg :: SMPClientAgentConfig,
     apnsConfig :: APNSPushClientConfig,
+    allowTestPushProvider :: Bool,
     subsBatchSize :: Int,
     inactiveClientExpiration :: Maybe ExpirationConfig,
     dbStoreConfig :: PostgresStoreCfg,
@@ -173,7 +174,7 @@ data SMPSubscriber = SMPSubscriber
   }
 
 data NtfPushServer = NtfPushServer
-  { pushWorkers :: TMap (Maybe T.Text, PushProvider) PushWorkerVar,
+  { pushWorkers :: TMap (Maybe T.Text, PushProvider, Int) PushWorkerVar, -- Int is the worker shard
     pushWorkerSeq :: TVar Int,
     pushQSize :: Natural,
     pushClients :: TMap PushProvider PushClientVar,

src/Simplex/Messaging/Notifications/Server/Main.hs

@@ -193,6 +193,7 @@ ntfServerCLI cfgPath logPath =
                     persistErrorInterval = 0 -- seconds
                   },
               apnsConfig = defaultAPNSPushClientConfig,
+              allowTestPushProvider = False,
               subsBatchSize = 900,
               inactiveClientExpiration =
                 settingIsOn "INACTIVE_CLIENTS" "disconnect" ini

src/Simplex/Messaging/Notifications/Transport.hs

@@ -12,7 +12,6 @@ module Simplex.Messaging.Notifications.Transport
     VersionRangeNTF,
     pattern VersionNTF,
     THandleNTF,
-    invalidReasonNTFVersion,
     supportedClientNTFVRange,
     supportedServerNTFVRange,
     alpnSupportedNTFHandshakes,
@@ -20,12 +19,8 @@ module Simplex.Messaging.Notifications.Transport
     ntfClientHandshake,
   ) where
 
-import Control.Monad (forM)
 import Control.Monad.Except
 import Control.Monad.Trans.Except
-import Data.Attoparsec.ByteString.Char8 (Parser)
-import Data.ByteString.Char8 (ByteString)
-import qualified Data.ByteString.Char8 as B
 import Data.Word (Word16)
 import qualified Data.X509 as X
 import qualified Simplex.Messaging.Crypto as C
@@ -50,13 +45,10 @@ pattern VersionNTF :: Word16 -> VersionNTF
 pattern VersionNTF v = Version v
 
 initialNTFVersion :: VersionNTF
-initialNTFVersion = VersionNTF 1
+initialNTFVersion = VersionNTF 3
 
-authBatchCmdsNTFVersion :: VersionNTF
-authBatchCmdsNTFVersion = VersionNTF 2
-
-invalidReasonNTFVersion :: VersionNTF
-invalidReasonNTFVersion = VersionNTF 3
+_invalidReasonNTFVersion :: VersionNTF
+_invalidReasonNTFVersion = VersionNTF 3
 
 currentClientNTFVersion :: VersionNTF
 currentClientNTFVersion = VersionNTF 3
@@ -67,9 +59,6 @@ currentServerNTFVersion = VersionNTF 3
 supportedClientNTFVRange :: VersionRangeNTF
 supportedClientNTFVRange = mkVersionRange initialNTFVersion currentClientNTFVersion
 
-legacyServerNTFVRange :: VersionRangeNTF
-legacyServerNTFVRange = mkVersionRange initialNTFVersion initialNTFVersion
-
 supportedServerNTFVRange :: VersionRangeNTF
 supportedServerNTFVRange = mkVersionRange initialNTFVersion currentServerNTFVersion
 
@@ -82,7 +71,7 @@ data NtfServerHandshake = NtfServerHandshake
   { ntfVersionRange :: VersionRangeNTF,
     sessionId :: SessionId,
     -- pub key to agree shared secrets for command authorization and entity ID encryption.
-    authPubKey :: Maybe (X.SignedExact X.PubKey)
+    authPubKey :: X.SignedExact X.PubKey
   }
 
 data NtfClientHandshake = NtfClientHandshake
@@ -94,25 +83,13 @@ data NtfClientHandshake = NtfClientHandshake
 
 instance Encoding NtfServerHandshake where
   smpEncode NtfServerHandshake {ntfVersionRange, sessionId, authPubKey} =
-    B.concat
-      [ smpEncode (ntfVersionRange, sessionId),
-        encodeAuthEncryptCmds (maxVersion ntfVersionRange) $ C.SignedObject <$> authPubKey
-      ]
+    smpEncode (ntfVersionRange, sessionId, C.SignedObject authPubKey)
 
   smpP = do
     (ntfVersionRange, sessionId) <- smpP
-    -- TODO drop SMP v6: remove special parser and make key non-optional
-    authPubKey <- authEncryptCmdsP (maxVersion ntfVersionRange) $ C.getSignedExact <$> smpP
+    authPubKey <- C.getSignedExact <$> smpP
     pure NtfServerHandshake {ntfVersionRange, sessionId, authPubKey}
 
-encodeAuthEncryptCmds :: Encoding a => VersionNTF -> Maybe a -> ByteString
-encodeAuthEncryptCmds v k
-  | v >= authBatchCmdsNTFVersion = maybe "" smpEncode k
-  | otherwise = ""
-
-authEncryptCmdsP :: VersionNTF -> Parser a -> Parser (Maybe a)
-authEncryptCmdsP v p = if v >= authBatchCmdsNTFVersion then Just <$> p else pure Nothing
-
 instance Encoding NtfClientHandshake where
   smpEncode NtfClientHandshake {ntfVersion, keyHash} =
     smpEncode (ntfVersion, keyHash)
@@ -122,11 +99,10 @@ instance Encoding NtfClientHandshake where
 
 -- | Notifcations server transport handshake.
 ntfServerHandshake :: forall c. Transport c => C.APrivateSignKey -> c 'TServer -> C.KeyPairX25519 -> C.KeyHash -> VersionRangeNTF -> ExceptT TransportError IO (THandleNTF c 'TServer)
-ntfServerHandshake serverSignKey c (k, pk) kh ntfVRange = do
+ntfServerHandshake serverSignKey c (k, pk) kh ntfVersionRange = do
   let th@THandle {params = THandleParams {sessionId}} = ntfTHandle c
-  let sk = C.signX509 serverSignKey $ C.publicToX509 k
-  let ntfVersionRange = maybe legacyServerNTFVRange (const ntfVRange) $ getSessionALPN c
-  sendHandshake th $ NtfServerHandshake {sessionId, ntfVersionRange, authPubKey = Just sk}
+      authPubKey = C.signX509 serverSignKey $ C.publicToX509 k
+  sendHandshake th $ NtfServerHandshake {sessionId, ntfVersionRange, authPubKey}
   getHandshake th >>= \case
     NtfClientHandshake {ntfVersion = v, keyHash}
       | keyHash /= kh ->
@@ -140,18 +116,18 @@ ntfServerHandshake serverSignKey c (k, pk) kh ntfVRange = do
 ntfClientHandshake :: forall c. Transport c => c 'TClient -> C.KeyHash -> VersionRangeNTF -> Bool -> Maybe (ServiceCredentials, C.KeyPairEd25519) -> ExceptT TransportError IO (THandleNTF c 'TClient)
 ntfClientHandshake c keyHash ntfVRange _proxyServer _serviceKeys = do
   let th@THandle {params = THandleParams {sessionId}} = ntfTHandle c
-  NtfServerHandshake {sessionId = sessId, ntfVersionRange, authPubKey = sk'} <- getHandshake th
+  NtfServerHandshake {sessionId = sessId, ntfVersionRange, authPubKey} <- getHandshake th
   if sessionId /= sessId
     then throwE TEBadSession
     else case ntfVersionRange `compatibleVRange` ntfVRange of
       Just (Compatible vr) -> do
-        ck_ <- forM sk' $ \signedKey -> liftEitherWith (const $ TEHandshake BAD_AUTH) $ do
+        ck <- liftEitherWith (const $ TEHandshake BAD_AUTH) $ do
           serverKey <- getServerVerifyKey c
-          pubKey <- C.verifyX509 serverKey signedKey
-          (,CertChainPubKey (getPeerCertChain c) signedKey) <$> C.x509ToPublic' pubKey
+          pubKey <- C.verifyX509 serverKey authPubKey
+          (,CertChainPubKey (getPeerCertChain c) authPubKey) <$> C.x509ToPublic' pubKey
         let v = maxVersion vr
         sendHandshake th $ NtfClientHandshake {ntfVersion = v, keyHash}
-        pure $ ntfThHandleClient th v vr ck_
+        pure $ ntfThHandleClient th v vr ck
       Nothing -> throwE TEVersion
 
 ntfThHandleServer :: forall c. THandleNTF c 'TServer -> VersionNTF -> VersionRangeNTF -> C.PrivateKeyX25519 -> THandleNTF c 'TServer
@@ -159,17 +135,16 @@ ntfThHandleServer th v vr pk =
   let thAuth = THAuthServer {serverPrivKey = pk, peerClientService = Nothing, sessSecret' = Nothing}
    in ntfThHandle_ th v vr (Just thAuth)
 
-ntfThHandleClient :: forall c. THandleNTF c 'TClient -> VersionNTF -> VersionRangeNTF -> Maybe (C.PublicKeyX25519, CertChainPubKey) -> THandleNTF c 'TClient
+ntfThHandleClient :: forall c. THandleNTF c 'TClient -> VersionNTF -> VersionRangeNTF -> (C.PublicKeyX25519, CertChainPubKey) -> THandleNTF c 'TClient
 ntfThHandleClient th v vr ck_ =
-  let thAuth = clientTHParams <$> ck_
+  let thAuth = Just $ clientTHParams ck_
       clientTHParams (k, ck) = THAuthClient {peerServerPubKey = k, peerServerCertKey = ck, clientService = Nothing, sessSecret = Nothing}
    in ntfThHandle_ th v vr thAuth
 
 ntfThHandle_ :: forall c p. THandleNTF c p -> VersionNTF -> VersionRangeNTF -> Maybe (THandleAuth p) -> THandleNTF c p
 ntfThHandle_ th@THandle {params} v vr thAuth =
   -- TODO drop SMP v6: make thAuth non-optional
-  let v3 = v >= authBatchCmdsNTFVersion
-      params' = params {thVersion = v, thServerVRange = vr, thAuth, implySessId = v3, batch = v3}
+  let params' = params {thVersion = v, thServerVRange = vr, thAuth}
    in (th :: THandleNTF c p) {params = params'}
 
 ntfTHandle :: Transport c => c p -> THandleNTF c p
@@ -183,8 +158,8 @@ ntfTHandle c = THandle {connection = c, params}
           thVersion = v,
           thServerVRange = versionToRange v,
           thAuth = Nothing,
-          implySessId = False,
+          implySessId = True,
           encryptBlock = Nothing,
-          batch = False,
-          serviceAuth = False
+          serviceAuth = False,
+          serverInfo = Nothing
         }

src/Simplex/Messaging/Protocol.hs

@@ -80,6 +80,7 @@ module Simplex.Messaging.Protocol
     ErrorType (..),
     CommandError (..),
     ProxyError (..),
+    NameErrorType (..),
     BrokerErrorType (..),
     NetworkError (..),
     BlockingInfo (..),
@@ -163,6 +164,7 @@ module Simplex.Messaging.Protocol
     EncTransmission (..),
     FwdResponse (..),
     FwdTransmission (..),
+    NameRecord (..),
     MsgFlags (..),
     initialSMPClientVersion,
     currentSMPClientVersion,
@@ -263,10 +265,12 @@ import Simplex.Messaging.Agent.Store.DB (Binary (..), FromField (..), ToField (.
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
+import Simplex.Messaging.Names.Record (NameRecord (..))
 import Simplex.Messaging.Parsers
 import Simplex.Messaging.Protocol.Types
 import Simplex.Messaging.Server.QueueStore.QueueInfo
 import Simplex.Messaging.ServiceScheme
+import Simplex.Messaging.SimplexName (SimplexDomain)
 import Simplex.Messaging.Transport
 import Simplex.Messaging.Transport.Client (TransportHost, TransportHosts (..))
 import Simplex.Messaging.Util (bshow, eitherToMaybe, safeDecodeUtf8, (<$?>))
@@ -308,18 +312,13 @@ currentSMPClientVersion = VersionSMPC 4
 supportedSMPClientVRange :: VersionRangeSMPC
 supportedSMPClientVRange = mkVersionRange initialSMPClientVersion currentSMPClientVersion
 
--- TODO v6.0 remove dependency on version
-maxMessageLength :: VersionSMP -> Int
-maxMessageLength v
-  | v >= encryptedBlockSMPVersion = 16048 -- max 16048
-  | v >= sendingProxySMPVersion = 16064 -- max 16067
-  | otherwise = 16088 -- 16048 - always use this size to determine allowed ranges
+maxMessageLength :: Int
+maxMessageLength = 16048 -- max 16048
 
 paddedProxiedTLength :: Int
 paddedProxiedTLength = 16226 -- 16225 .. 16227
 
--- TODO v7.0 change to 16048
-type MaxMessageLen = 16088
+type MaxMessageLen = 16048
 
 -- 16 extra bytes: 8 for timestamp and 8 for flags (7 flags and the space, only 1 flag is currently used)
 type MaxRcvMessageLen = MaxMessageLen + 16 -- 16104, the padded size is 16106
@@ -343,6 +342,7 @@ data Party
   | LinkClient
   | ProxiedClient
   | ProxyService
+  | Resolver
   deriving (Show)
 
 -- | Singleton types for SMP protocol clients
@@ -357,6 +357,7 @@ data SParty :: Party -> Type where
   SSenderLink :: SParty LinkClient
   SProxiedClient :: SParty ProxiedClient
   SProxyService :: SParty ProxyService
+  SResolver :: SParty Resolver
 
 instance TestEquality SParty where
   testEquality SCreator SCreator = Just Refl
@@ -369,6 +370,7 @@ instance TestEquality SParty where
   testEquality SSenderLink SSenderLink = Just Refl
   testEquality SProxiedClient SProxiedClient = Just Refl
   testEquality SProxyService SProxyService = Just Refl
+  testEquality SResolver SResolver = Just Refl
   testEquality _ _ = Nothing
 
 deriving instance Show (SParty p)
@@ -395,6 +397,8 @@ instance PartyI ProxiedClient where sParty = SProxiedClient
 
 instance PartyI ProxyService where sParty = SProxyService
 
+instance PartyI Resolver where sParty = SResolver
+
 -- command parties that can read queues
 type family QueueParty (p :: Party) :: Constraint where
   QueueParty Recipient = ()
@@ -473,6 +477,7 @@ partyClientRole = \case
   SSenderLink -> Just SRMessaging
   SProxiedClient -> Just SRMessaging
   SProxyService -> Just SRProxy
+  SResolver -> Just SRMessaging
 {-# INLINE partyClientRole #-}
 
 partyServiceRole :: ServiceParty p => SParty p -> SMPServiceRole
@@ -597,6 +602,8 @@ data Command (p :: Party) where
   -- - entity ID: empty
   -- - corrId: unique correlation ID between proxy and relay, also used as a nonce to encrypt forwarded transmission
   RFWD :: EncFwdTransmission -> Command ProxyService -- use CorrId as CbNonce, proxy to relay
+  -- Resolve SimpleX name.
+  RSLV :: SimplexDomain -> Command Resolver
 
 deriving instance Show (Command p)
 
@@ -732,6 +739,8 @@ data BrokerMsg where
   OK :: BrokerMsg
   ERR :: ErrorType -> BrokerMsg
   PONG :: BrokerMsg
+  -- Resolved SimpleX name.
+  RNAME :: NameRecord -> BrokerMsg
   deriving (Eq, Show)
 
 data RcvMessage = RcvMessage
@@ -942,6 +951,7 @@ data CommandTag (p :: Party) where
   RFWD_ :: CommandTag ProxyService
   NSUB_ :: CommandTag Notifier
   NSUBS_ :: CommandTag NotifierService
+  RSLV_ :: CommandTag Resolver
 
 data CmdTag = forall p. PartyI p => CT (SParty p) (CommandTag p)
 
@@ -968,6 +978,7 @@ data BrokerMsgTag
   | OK_
   | ERR_
   | PONG_
+  | RNAME_
   deriving (Show)
 
 class ProtocolMsgTag t where
@@ -1004,6 +1015,7 @@ instance PartyI p => Encoding (CommandTag p) where
     RFWD_ -> "RFWD"
     NSUB_ -> "NSUB"
     NSUBS_ -> "NSUBS"
+    RSLV_ -> "RSLV"
   smpP = messageTagP
 
 instance ProtocolMsgTag CmdTag where
@@ -1032,6 +1044,7 @@ instance ProtocolMsgTag CmdTag where
     "RFWD" -> Just $ CT SProxyService RFWD_
     "NSUB" -> Just $ CT SNotifier NSUB_
     "NSUBS" -> Just $ CT SNotifierService NSUBS_
+    "RSLV" -> Just $ CT SResolver RSLV_
     _ -> Nothing
 
 instance Encoding CmdTag where
@@ -1061,6 +1074,7 @@ instance Encoding BrokerMsgTag where
     OK_ -> "OK"
     ERR_ -> "ERR"
     PONG_ -> "PONG"
+    RNAME_ -> "RNAME"
   smpP = messageTagP
 
 instance ProtocolMsgTag BrokerMsgTag where
@@ -1083,6 +1097,7 @@ instance ProtocolMsgTag BrokerMsgTag where
     "OK" -> Just OK_
     "ERR" -> Just ERR_
     "PONG" -> Just PONG_
+    "RNAME" -> Just RNAME_
     _ -> Nothing
 
 -- | SMP message body format
@@ -1526,11 +1541,14 @@ queueIdHash = IdsHash . C.md5Hash . unEntityId
 {-# INLINE queueIdHash #-}
 
 addServiceSubs :: (Int64, IdsHash) -> (Int64, IdsHash) -> (Int64, IdsHash)
-addServiceSubs (n', idsHash') (n, idsHash) = (n + n', idsHash <> idsHash')
+addServiceSubs (n', idsHash') (n, idsHash) =
+  let !n'' = n + n'
+      !h = idsHash <> idsHash'
+   in (n'', h)
 
 subtractServiceSubs :: (Int64, IdsHash) -> (Int64, IdsHash) -> (Int64, IdsHash)
 subtractServiceSubs (n', idsHash') (n, idsHash)
-  | n > n' = (n - n', idsHash <> idsHash') -- concat is a reversible xor: (x `xor` y) `xor` y == x
+  | n > n' = let !n'' = n - n'; !h = idsHash <> idsHash' in (n'', h) -- concat is a reversible xor: (x `xor` y) `xor` y == x
   | otherwise = (0, mempty)
 
 data ProtocolErrorType = PECmdSyntax | PECmdUnknown | PESession | PEBlock
@@ -1559,16 +1577,28 @@ data ErrorType
     STORE {storeErr :: Text}
   | -- | ACK command is sent without message to be acknowledged
     NO_MSG
-  | -- | sent message is too large (> maxMessageLength = 16088 bytes)
+  | -- | sent message is too large (> maxMessageLength = 16048 bytes)
     LARGE_MSG
   | -- | relay public key is expired
     EXPIRED
   | -- | internal server error
     INTERNAL
+  | -- | name resolution error
+    NAME {nameErr :: NameErrorType}
   | -- | used internally, never returned by the server (to be removed)
     DUPLICATE_ -- not part of SMP protocol, used internally
   deriving (Eq, Show)
 
+-- | Name resolution error
+data NameErrorType
+  = -- | the names role / resolver is not configured on this server
+    NO_RESOLVER
+  | -- | the name is not registered (resolver returned not-found)
+    NOT_FOUND
+  | -- | backing resolver/RPC failure - contains the diagnostic detail
+    RESOLVER {resolverErr :: Text}
+  deriving (Eq, Show)
+
 instance StrEncoding ErrorType where
   strEncode = \case
     BLOCK -> "BLOCK"
@@ -1585,6 +1615,7 @@ instance StrEncoding ErrorType where
     LARGE_MSG -> "LARGE_MSG"
     EXPIRED -> "EXPIRED"
     INTERNAL -> "INTERNAL"
+    NAME e -> "NAME " <> strEncode e
     DUPLICATE_ -> "DUPLICATE_"
   strP =
     A.choice
@@ -1592,6 +1623,7 @@ instance StrEncoding ErrorType where
         "SESSION" $> SESSION,
         "CMD " *> (CMD <$> parseRead1),
         "PROXY " *> (PROXY <$> strP),
+        "NAME " *> (NAME <$> strP),
         "AUTH" $> AUTH,
         "BLOCKED " *> strP,
         "SERVICE" $> SERVICE,
@@ -1758,13 +1790,11 @@ instance PartyI p => ProtocolEncoding SMPVersion ErrorType (Command p) where
   type Tag (Command p) = CommandTag p
   encodeProtocol v = \case
     NEW NewQueueReq {rcvAuthKey = rKey, rcvDhKey = dhKey, auth_, subMode, queueReqData, ntfCreds}
-      | v >= newNtfCredsSMPVersion -> new <> e (auth_, subMode, queueReqData, ntfCreds)
-      | v >= shortLinksSMPVersion -> new <> e (auth_, subMode, queueReqData)
-      | v >= sndAuthKeySMPVersion -> new <> e (auth_, subMode, senderCanSecure (queueReqMode <$> queueReqData))
-      | otherwise -> new <> auth <> e subMode
+      | v >= newNtfCredsSMPVersion -> new <> e (subMode, queueReqData, ntfCreds)
+      | v >= shortLinksSMPVersion -> new <> e (subMode, queueReqData)
+      | otherwise -> new <> e (subMode, senderCanSecure (queueReqMode <$> queueReqData))
       where
-        new = e (NEW_, ' ', rKey, dhKey)
-        auth = maybe "" (e . ('A',)) auth_
+        new = e (NEW_, ' ', rKey, dhKey, auth_)
     SUB -> e SUB_
     SUBS n idsHash
       | v >= rcvServiceSMPVersion -> e (SUBS_, ' ', n, idsHash)
@@ -1792,6 +1822,7 @@ instance PartyI p => ProtocolEncoding SMPVersion ErrorType (Command p) where
     PRXY host auth_ -> e (PRXY_, ' ', host, auth_)
     PFWD fwdV pubKey (EncTransmission s) -> e (PFWD_, ' ', fwdV, pubKey, Tail s)
     RFWD (EncFwdTransmission s) -> e (RFWD_, ' ', Tail s)
+    RSLV d -> e (RSLV_, ' ', d)
     where
       e :: Encoding a => a -> ByteString
       e = smpEncode
@@ -1816,6 +1847,7 @@ instance PartyI p => ProtocolEncoding SMPVersion ErrorType (Command p) where
     PRXY {} -> noAuthCmd
     PFWD {} -> entityCmd
     RFWD _ -> noAuthCmd
+    RSLV _ -> noAuthCmd
     SUB -> serviceCmd
     NSUB -> serviceCmd
     -- other client commands must have both signature and queue ID
@@ -1847,21 +1879,19 @@ instance ProtocolEncoding SMPVersion ErrorType Cmd where
     CT SCreator NEW_ -> Cmd SCreator <$> newCmd
       where
         newCmd
-          | v >= newNtfCredsSMPVersion = new smpP smpP smpP
-          | v >= shortLinksSMPVersion = new smpP smpP nothing
-          | v >= sndAuthKeySMPVersion = new smpP (qReq <$> smpP) nothing
-          | otherwise = new auth nothing nothing
+          | v >= newNtfCredsSMPVersion = new smpP smpP
+          | v >= shortLinksSMPVersion = new smpP nothing
+          | otherwise = new (qReq <$> smpP) nothing
           where
             nothing = pure Nothing
-            new p1 p2 p3 = NEW <$> do
+            new p2 p3 = NEW <$> do
               rcvAuthKey <- _smpP
               rcvDhKey <- smpP
-              auth_ <- p1
+              auth_ <- smpP
               subMode <- smpP
               queueReqData <- p2
               ntfCreds <- p3
               pure NewQueueReq {rcvAuthKey, rcvDhKey, auth_, subMode, queueReqData, ntfCreds}
-            auth = optional (A.char 'A' *> smpP)
             qReq sndSecure = Just $ if sndSecure then QRMessaging Nothing else QRContact Nothing
     CT SRecipient tag ->
       Cmd SRecipient <$> case tag of
@@ -1899,6 +1929,7 @@ instance ProtocolEncoding SMPVersion ErrorType Cmd where
     CT SNotifierService NSUBS_
       | v >= rcvServiceSMPVersion -> Cmd SNotifierService <$> (NSUBS <$> _smpP <*> smpP)
       | otherwise -> pure $ Cmd SNotifierService $ NSUBS (-1) mempty
+    CT SResolver RSLV_ -> Cmd SResolver . RSLV <$> _smpP <* A.takeByteString
 
   fromProtocolError = fromProtocolError @SMPVersion @ErrorType @BrokerMsg
   {-# INLINE fromProtocolError #-}
@@ -1910,11 +1941,10 @@ instance ProtocolEncoding SMPVersion ErrorType BrokerMsg where
   type Tag BrokerMsg = BrokerMsgTag
   encodeProtocol v = \case
     IDS QIK {rcvId, sndId, rcvPublicDhKey = srvDh, queueMode, linkId, serviceId, serverNtfCreds}
-      | v >= newNtfCredsSMPVersion -> ids <> e queueMode <> e linkId <> e serviceId <> e serverNtfCreds
-      | v >= serviceCertsSMPVersion -> ids <> e queueMode <> e linkId <> e serviceId
-      | v >= shortLinksSMPVersion -> ids <> e queueMode <> e linkId
-      | v >= sndAuthKeySMPVersion -> ids <> e (senderCanSecure queueMode)
-      | otherwise -> ids
+      | v >= newNtfCredsSMPVersion -> ids <> e (queueMode, linkId, serviceId, serverNtfCreds)
+      | v >= serviceCertsSMPVersion -> ids <> e (queueMode, linkId, serviceId)
+      | v >= shortLinksSMPVersion -> ids <> e (queueMode, linkId)
+      | otherwise -> ids <> e (senderCanSecure queueMode)
       where
         ids = e (IDS_, ' ', rcvId, sndId, srvDh)
     LNK sId d -> e (LNK_, ' ', sId, d)
@@ -1932,19 +1962,17 @@ instance ProtocolEncoding SMPVersion ErrorType BrokerMsg where
     PRES (EncResponse encBlock) -> e (PRES_, ' ', Tail encBlock)
     END -> e END_
     ENDS n idsHash -> serviceResp ENDS_ n idsHash
-    DELD
-      | v >= deletedEventSMPVersion -> e DELD_
-      | otherwise -> e END_
+    DELD -> e DELD_
     INFO info -> e (INFO_, ' ', info)
     OK -> e OK_
     ERR err -> e (ERR_, ' ', err')
       where
         err' = case err of
           BLOCKED info
-            | v < blockedEntitySMPVersion -> AUTH
             | v < clientNoticesSMPVersion -> BLOCKED info {notice = Nothing}
           _ -> err
     PONG -> e PONG_
+    RNAME rec -> e (RNAME_, ' ', Tail $ LB.toStrict $ J.encode rec)
     where
       e :: Encoding a => a -> ByteString
       e = smpEncode
@@ -1963,8 +1991,7 @@ instance ProtocolEncoding SMPVersion ErrorType BrokerMsg where
       | v >= newNtfCredsSMPVersion -> ids smpP smpP smpP smpP
       | v >= serviceCertsSMPVersion -> ids smpP smpP smpP nothing
       | v >= shortLinksSMPVersion -> ids smpP smpP nothing nothing
-      | v >= sndAuthKeySMPVersion -> ids (qm <$> smpP) nothing nothing nothing
-      | otherwise -> ids nothing nothing nothing nothing
+      | otherwise -> ids (qm <$> smpP) nothing nothing nothing
       where
         qm sndSecure = Just $ if sndSecure then QMMessaging else QMContact
         nothing = pure Nothing
@@ -1992,6 +2019,7 @@ instance ProtocolEncoding SMPVersion ErrorType BrokerMsg where
     OK_ -> pure OK
     ERR_ -> ERR <$> _smpP
     PONG_ -> pure PONG
+    RNAME_ -> fmap RNAME . J.eitherDecodeStrict . unTail <$?> _smpP
     where
       serviceRespP resp
         | v >= rcvServiceSMPVersion = resp <$> _smpP <*> smpP
@@ -2014,6 +2042,7 @@ instance ProtocolEncoding SMPVersion ErrorType BrokerMsg where
     PKEY {} -> noEntityMsg
     RRES _ -> noEntityMsg
     ALLS -> noEntityMsg
+    RNAME _ -> noEntityMsg
     -- other broker responses must have queue ID
     _
       | B.null entId -> Left $ CMD NO_ENTITY
@@ -2056,6 +2085,7 @@ instance Encoding ErrorType where
     NO_MSG -> "NO_MSG"
     LARGE_MSG -> "LARGE_MSG"
     INTERNAL -> "INTERNAL"
+    NAME err -> "NAME " <> smpEncode err
     DUPLICATE_ -> "DUPLICATE_"
 
   smpP =
@@ -2074,9 +2104,26 @@ instance Encoding ErrorType where
       "NO_MSG" -> pure NO_MSG
       "LARGE_MSG" -> pure LARGE_MSG
       "INTERNAL" -> pure INTERNAL
+      "NAME" -> NAME <$> _smpP
       "DUPLICATE_" -> pure DUPLICATE_
       _ -> fail "bad ErrorType"
 
+instance Encoding NameErrorType where
+  smpEncode = \case
+    NO_RESOLVER -> "NO_RESOLVER"
+    NOT_FOUND -> "NOT_FOUND"
+    RESOLVER e -> "RESOLVER " <> encodeUtf8 e
+  smpP =
+    A.takeTill (== ' ') >>= \case
+      "NO_RESOLVER" -> pure NO_RESOLVER
+      "NOT_FOUND" -> pure NOT_FOUND
+      "RESOLVER" -> RESOLVER . safeDecodeUtf8 <$> (A.space *> A.takeByteString)
+      _ -> fail "bad NameErrorType"
+
+instance StrEncoding NameErrorType where
+  strEncode = smpEncode
+  strP = smpP
+
 instance Encoding CommandError where
   smpEncode e = case e of
     UNKNOWN -> "UNKNOWN"
@@ -2229,19 +2276,8 @@ batchTransmissions params = batchTransmissions' params . L.map (,())
 
 -- | encodes and batches transmissions into blocks
 batchTransmissions' :: forall v p r. THandleParams v p -> NonEmpty (Either TransportError SentRawTransmission, r) -> [TransportBatch r]
-batchTransmissions' THandleParams {batch, blockSize = bSize, serviceAuth} ts
-  | batch = batchTransmissions_ bSize $ L.map (first $ fmap $ tEncodeForBatch serviceAuth) ts
-  | otherwise = map mkBatch1 $ L.toList ts
-  where
-    mkBatch1 :: (Either TransportError SentRawTransmission, r) -> TransportBatch r
-    mkBatch1 (t_, r) = case t_ of
-      Left e -> TBError e r
-      Right t
-        -- 2 bytes are reserved for pad size
-        | B.length s <= bSize - 2 -> TBTransmission s r
-        | otherwise -> TBError TELargeMsg r
-        where
-          s = tEncode serviceAuth t
+batchTransmissions' THandleParams {blockSize, serviceAuth} ts =
+  batchTransmissions_ blockSize $ L.map (first $ fmap $ tEncodeForBatch serviceAuth) ts
 
 -- | Pack encoded transmissions into batches
 batchTransmissions_ :: Int -> NonEmpty (Either TransportError ByteString, r) -> [TransportBatch r]
@@ -2305,9 +2341,8 @@ tGetParse th@THandle {params} = eitherList (tParse params) <$> tGetBlock th
 {-# INLINE tGetParse #-}
 
 tParse :: THandleParams v p -> ByteString -> NonEmpty (Either TransportError RawTransmission)
-tParse thParams@THandleParams {batch} s
-  | batch = eitherList (L.map (\(Large t) -> tParse1 t)) ts
-  | otherwise = [tParse1 s]
+tParse thParams s =
+  eitherList (L.map (tParse1 . unLarge)) ts
   where
     tParse1 = parse (transmissionP thParams) TEBadBlock
     ts = parse smpP TEBadBlock s
@@ -2376,4 +2411,4 @@ $(J.deriveJSON (sumTypeJSON id) ''BrokerErrorType)
 $(J.deriveJSON defaultJSON ''BlockingInfo)
 
 -- run deriveJSON in one TH splice to allow mutual instance
-$(concat <$> mapM @[] (J.deriveJSON (sumTypeJSON id)) [''ProxyError, ''ErrorType])
+$(concat <$> mapM @[] (J.deriveJSON (sumTypeJSON id)) [''ProxyError, ''NameErrorType, ''ErrorType])

src/Simplex/Messaging/Server.hs

@@ -56,6 +56,7 @@ import Control.Monad.Trans.Except
 import Control.Monad.STM (retry)
 import Crypto.Random (ChaChaDRG)
 import Data.Bifunctor (first, second)
+import qualified Data.Aeson as J
 import Data.ByteString.Base64 (encode)
 import qualified Data.ByteString.Builder as BLD
 import Data.ByteString.Char8 (ByteString)
@@ -65,7 +66,7 @@ import Data.Constraint (Dict (..))
 import Data.Dynamic (toDyn)
 import Data.Either (fromRight, partitionEithers)
 import Data.Foldable (foldrM)
-import Data.Functor (($>))
+import Data.Functor (($>), (<&>))
 import Data.IORef
 import Data.Int (Int64)
 import qualified Data.IntMap.Strict as IM
@@ -103,11 +104,13 @@ import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol
+import Simplex.Messaging.SimplexName (SimplexDomain)
 import Simplex.Messaging.Server.Control
 import Simplex.Messaging.Server.Env.STM as Env
 import Simplex.Messaging.Server.Expiration
 import Simplex.Messaging.Server.MsgStore
 import Simplex.Messaging.Server.MsgStore.Journal (JournalMsgStore, JournalQueue (..), getJournalQueueMessages)
+import Simplex.Messaging.Server.Names (NamesEnv, closeNamesEnv, resolveName)
 import Simplex.Messaging.Server.MsgStore.STM
 import Simplex.Messaging.Server.MsgStore.Types
 import Simplex.Messaging.Server.NtfStore
@@ -245,7 +248,9 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg, startOpt
       saveServerStats
 
     closeServer :: M s ()
-    closeServer = asks (smpAgent . proxyAgent) >>= liftIO . closeSMPClientAgent
+    closeServer = do
+      asks (smpAgent . proxyAgent) >>= liftIO . closeSMPClientAgent
+      asks namesEnv >>= liftIO . mapM_ closeNamesEnv
 
     serverThread ::
       forall sub. String ->
@@ -329,21 +334,25 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg, startOpt
         endPreviousSubscriptions = mapM_ $ \(c, subAction, evt) -> do
           atomically $ modifyTVar' pendingEvents $ IM.alter (Just . maybe [evt] (evt <|)) (clientId c)
           case subAction of
-            CSAEndSub qId -> atomically (endSub c qId) >>= a unsub_
-              where
-                a (Just unsub) (Just s) = unsub s
-                a _ _ = pure ()
-            CSAEndServiceSub qId -> atomically $ do
-              modifyTVar' (clientServiceSubs c) decrease
-              modifyTVar' totalServiceSubs decrease
-              where
-                decrease = subtractServiceSubs (1, queueIdHash qId)
+            CSAEndSub qId -> atomically (endSub c qId) >>= unsubPrev
+            -- like endSub, also removes the delivery subscription from the service client's subscriptions map,
+            -- otherwise the map retains entries for queues unassociated/deleted while the service stays connected.
+            CSAEndServiceSub qId -> atomically (endServiceQueueSub c qId) >>= unsubPrev
             CSADecreaseSubs changedSubs -> do
               atomically $ modifyTVar' totalServiceSubs $ subtractServiceSubs changedSubs
               forM_ unsub_ $ \unsub -> atomically (swapTVar (clientSubs c) M.empty) >>= mapM_ unsub
           where
+            unsubPrev :: Maybe sub -> IO ()
+            unsubPrev s_ = sequence_ (unsub_ <*> s_)
             endSub :: Client s -> QueueId -> STM (Maybe sub)
             endSub c qId = TM.lookupDelete qId (clientSubs c) >>= (removeWhenNoSubs c $>)
+            endServiceQueueSub :: Client s -> QueueId -> STM (Maybe sub)
+            endServiceQueueSub c qId = do
+              modifyTVar' (clientServiceSubs c) decrease
+              modifyTVar' totalServiceSubs decrease
+              endSub c qId
+              where
+                decrease = subtractServiceSubs (1, queueIdHash qId)
         -- remove client from server's subscribed cients
         removeWhenNoSubs c = do
           noClientSubs <- null <$> readTVar (clientSubs c)
@@ -513,7 +522,7 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg, startOpt
       initialDelay <- (startAt -) . fromIntegral . (`div` 1000000_000000) . diffTimeToPicoseconds . utctDayTime <$> liftIO getCurrentTime
       liftIO $ putStrLn $ "server stats log enabled: " <> statsFilePath
       liftIO $ threadDelay' $ 1000000 * (initialDelay + if initialDelay < 0 then 86400 else 0)
-      ss@ServerStats {fromTime, qCreated, qSecured, qDeletedAll, qDeletedAllB, qDeletedNew, qDeletedSecured, qSub, qSubAllB, qSubAuth, qSubDuplicate, qSubProhibited, qSubEnd, qSubEndB, ntfCreated, ntfDeleted, ntfDeletedB, ntfSub, ntfSubB, ntfSubAuth, ntfSubDuplicate, msgSent, msgSentAuth, msgSentQuota, msgSentLarge, msgRecv, msgRecvGet, msgGet, msgGetNoMsg, msgGetAuth, msgGetDuplicate, msgGetProhibited, msgExpired, activeQueues, msgSentNtf, msgRecvNtf, activeQueuesNtf, qCount, msgCount, ntfCount, pRelays, pRelaysOwn, pMsgFwds, pMsgFwdsOwn, pMsgFwdsRecv, rcvServices, ntfServices}
+      ss@ServerStats {fromTime, qCreated, qSecured, qDeletedAll, qDeletedAllB, qDeletedNew, qDeletedSecured, qSub, qSubAllB, qSubAuth, qSubDuplicate, qSubProhibited, qSubEnd, qSubEndB, ntfCreated, ntfDeleted, ntfDeletedB, ntfSub, ntfSubB, ntfSubAuth, ntfSubDuplicate, msgSent, msgSentAuth, msgSentQuota, msgSentLarge, msgRecv, msgRecvGet, msgGet, msgGetNoMsg, msgGetAuth, msgGetDuplicate, msgGetProhibited, msgExpired, activeQueues, msgSentNtf, msgRecvNtf, activeQueuesNtf, qCount, msgCount, ntfCount, pRelays, pRelaysOwn, pMsgFwds, pMsgFwdsOwn, pMsgFwdsRecv, rcvServices, ntfServices, rslvStats}
         <- asks serverStats
       st <- asks msgStore
       EntityCounts {queueCount, notifierCount, rcvServiceCount, ntfServiceCount, rcvServiceQueuesCount, ntfServiceQueuesCount} <-
@@ -576,6 +585,7 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg, startOpt
           qCount' <- readIORef qCount
           msgCount' <- readIORef msgCount
           ntfCount' <- readIORef ntfCount
+          rslvStats' <- getResetNameResolverStatsData rslvStats
           T.hPutStrLn h $
             T.intercalate
               ","
@@ -649,6 +659,7 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg, startOpt
                      ]
                        <> showServiceStats rcvServices'
                        <> showServiceStats ntfServices'
+                       <> showNameResolverStats rslvStats'
               )
         liftIO $ threadDelay' interval
       where
@@ -656,6 +667,8 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg, startOpt
           map tshow [_pRequests, _pSuccesses, _pErrorsConnect, _pErrorsCompat, _pErrorsOther]
         showServiceStats ServiceStatsData {_srvAssocNew, _srvAssocDuplicate, _srvAssocUpdated, _srvAssocRemoved, _srvSubCount, _srvSubDuplicate, _srvSubQueues, _srvSubEnd} =
           map tshow [_srvAssocNew, _srvAssocDuplicate, _srvAssocUpdated, _srvAssocRemoved, _srvSubCount, _srvSubDuplicate, _srvSubQueues, _srvSubEnd]
+        showNameResolverStats NameResolverStatsData {_rslvReqs, _rslvSucc, _rslvNotFound, _rslvResolverErrs, _rslvDisabled} =
+          map tshow [_rslvReqs, _rslvSucc, _rslvNotFound, _rslvResolverErrs, _rslvDisabled]
 
     prometheusMetricsThread_ :: ServerConfig s -> [M s ()]
     prometheusMetricsThread_ ServerConfig {prometheusInterval = Just interval, prometheusMetricsFile} =
@@ -727,9 +740,10 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg, startOpt
       idSize <- asks $ queueIdBytes . config
       kh <- asks serverIdentity
       ks <- atomically . C.generateKeyPair =<< asks random
-      ServerConfig {smpServerVRange, smpHandshakeTimeout} <- asks config
+      ServerConfig {smpServerVRange, smpHandshakeTimeout, information} <- asks config
+      let serverInfo = LB.toStrict . J.encode <$> information
       labelMyThread $ "smp handshake for " <> transportName tp
-      liftIO (timeout smpHandshakeTimeout . runExceptT $ smpServerHandshake srvCert srvSignKey h ks kh smpServerVRange $ getClientService ms g idSize) >>= \case
+      liftIO (timeout smpHandshakeTimeout . runExceptT $ smpServerHandshake srvCert srvSignKey h ks kh smpServerVRange serverInfo $ getClientService ms g idSize) >>= \case
         Just (Right th) -> runClientTransport th
         _ -> pure ()
 
@@ -1262,6 +1276,7 @@ verifyQueueTransmission service thAuth (tAuth, authorized, (corrId, entId, comma
     vc SNotifierService NSUBS {} = verifyServiceCmd
     vc SProxiedClient _ = VRVerified Nothing
     vc SProxyService (RFWD _) = VRVerified Nothing
+    vc SResolver (RSLV _) = VRVerified Nothing
     checkRole = case (service, partyClientRole p) of
       (Just THClientService {serviceRole}, Just role) -> serviceRole == role
       _ -> True
@@ -1364,11 +1379,10 @@ client
   ms
   clnt@Client {clientId, rcvQ, sndQ, msgQ, clientTHParams = thParams'@THandleParams {sessionId}, procThreads} = do
     labelMyThread . B.unpack $ "client $" <> encode sessionId <> " commands"
-    let THandleParams {thVersion} = thParams'
-        clntServiceId = (\THClientService {serviceId} -> serviceId) <$> (peerClientService =<< thAuth thParams')
+    let clntServiceId = (\THClientService {serviceId} -> serviceId) <$> (peerClientService =<< thAuth thParams')
         process batchSubs t acc@(rs, msgs) =
           (maybe acc (\(!r, !msg_) -> (r : rs, maybe msgs (: msgs) msg_)))
-            <$> processCommand clntServiceId thVersion batchSubs t
+            <$> processCommand clntServiceId batchSubs t
     forever $ do
       batch <- atomically (readTBQueue rcvQ)
       batchSubs <- prepareBatchSubs clntServiceId batch
@@ -1431,11 +1445,11 @@ client
                 pure . ERR $ smpProxyError e
             where
               proxyResp smp =
-                let THandleParams {sessionId = srvSessId, thVersion, thServerVRange, thAuth} = thParams smp
+                let THandleParams {sessionId = srvSessId, thServerVRange, thAuth} = thParams smp
                   in case compatibleVRange thServerVRange proxiedSMPRelayVRange of
                       -- Cap the destination relay version range to prevent client version fingerprinting.
                       -- See comment for proxiedSMPRelayVersion.
-                      Just (Compatible vr) | thVersion >= sendingProxySMPVersion -> case thAuth of
+                      Just (Compatible vr) -> case thAuth of
                         Just THAuthClient {peerServerCertKey} -> PKEY srvSessId vr peerServerCertKey
                         Nothing -> ERR $ transportErr TENoServerAuth
                       _ -> ERR $ transportErr TEVersion
@@ -1446,46 +1460,66 @@ client
         liftIO (lookupSMPServerClient a sessId) >>= \case
           Just (own, smp) -> do
             inc own pRequests
-            if v >= sendingProxySMPVersion
-              then forkProxiedCmd $ do
-                liftIO (runExceptT (forwardSMPTransmission smp corrId fwdV pubKey encBlock) `E.catches` clientHandlers)  >>= \case
-                  Right r -> PRES r <$ inc own pSuccesses
-                  Left e -> ERR (smpProxyError e) <$ case e of
-                    PCEProtocolError {} -> inc own pSuccesses
-                    _ -> inc own pErrorsOther
-              else Just (ERR $ transportErr TEVersion) <$ inc own pErrorsCompat
-            where
-              THandleParams {thVersion = v} = thParams smp
+            forkProxiedCmd $ do
+              liftIO (runExceptT (forwardSMPTransmission smp corrId fwdV pubKey encBlock) `E.catches` clientHandlers)  >>= \case
+                Right r -> PRES r <$ inc own pSuccesses
+                Left e -> ERR (smpProxyError e) <$ case e of
+                  PCEProtocolError {} -> inc own pSuccesses
+                  _ -> inc own pErrorsOther
           Nothing -> inc False pRequests >> inc False pErrorsConnect $> Just (ERR $ PROXY NO_SESSION)
       where
         forkProxiedCmd :: M s BrokerMsg -> M s (Maybe BrokerMsg)
-        forkProxiedCmd cmdAction = do
-          bracket_ wait signal . forkClient clnt (B.unpack $ "client $" <> encode sessionId <> " proxy") $ do
-            -- commands MUST be processed under a reasonable timeout or the client would halt
-            cmdAction >>= \t -> atomically $ writeTBQueue sndQ ([(corrId, EntityId sessId, t)], [])
-          pure Nothing
-          where
-            wait = do
-              ServerConfig {serverClientConcurrency} <- asks config
-              atomically $ do
-                used <- readTVar procThreads
-                when (used >= serverClientConcurrency) retry
-                writeTVar procThreads $! used + 1
-            signal = atomically $ modifyTVar' procThreads (\t -> t - 1)
+        forkProxiedCmd = forkCmd serverClientConcurrency corrId (EntityId sessId)
+    -- Run a slow command on a thread
+    forkCmd :: (ServerConfig s -> Int) -> CorrId -> EntityId -> M s BrokerMsg -> M s (Maybe a)
+    forkCmd concurrency corrId entId cmdAction = do
+      bracket_ wait signal . forkClient clnt (B.unpack $ "client $" <> encode sessionId <> " cmd") $
+        -- commands MUST be processed under a reasonable timeout or the client would halt
+        cmdAction >>= \t -> atomically $ writeTBQueue sndQ ([(corrId, entId, t)], [])
+      pure Nothing
+      where
+        wait = do
+          limit <- asks (concurrency . config)
+          atomically $ do
+            used <- readTVar procThreads
+            when (used >= limit) retry
+            writeTVar procThreads $! used + 1
+        signal = atomically $ modifyTVar' procThreads (\t -> t - 1)
+    rslvNamesEnv :: M s (Maybe NamesEnv)
+    rslvNamesEnv = do
+      st <- asks (rslvStats . serverStats)
+      incStat (rslvReqs st)
+      asks namesEnv >>= \case
+        Nothing -> incStat (rslvDisabled st) $> Nothing
+        Just nenv -> pure (Just nenv)
+    -- Runs on a forked thread so RSLV does not block other commands;
+    -- concurrency is limited by serverResolverConcurrency in forkCmd.
+    resolveNameMsg :: NamesEnv -> SimplexDomain -> M s BrokerMsg
+    resolveNameMsg nenv d = do
+      st <- asks (rslvStats . serverStats)
+      (selector, msg) <-
+        liftIO (resolveName nenv d) <&> \case
+          Right rec -> (rslvSucc, RNAME rec)
+          Left e@NOT_FOUND -> (rslvNotFound, ERR $ NAME e)
+          Left e -> (rslvResolverErrs, ERR $ NAME e)
+      incStat (selector st) $> msg
     transportErr :: TransportError -> ErrorType
     transportErr = PROXY . BROKER . TRANSPORT
     mkIncProxyStats :: MonadIO m => ProxyStats -> ProxyStats -> OwnServer -> (ProxyStats -> IORef Int) -> m ()
     mkIncProxyStats ps psOwn own sel = do
       incStat $ sel ps
       when own $ incStat $ sel psOwn
-    processCommand :: Maybe ServiceId -> VersionSMP -> Either ErrorType (Map RecipientId Message, Map RecipientId (Either ErrorType ()), Map RecipientId (Either ErrorType ())) -> VerifiedTransmission s -> M s (Maybe ResponseAndMessage)
-    processCommand clntServiceId clntVersion batchSubs (q_, (corrId, entId, cmd)) = case cmd of
+    processCommand :: Maybe ServiceId -> Either ErrorType (Map RecipientId Message, Map RecipientId (Either ErrorType ()), Map RecipientId (Either ErrorType ())) -> VerifiedTransmission s -> M s (Maybe ResponseAndMessage)
+    processCommand clntServiceId batchSubs (q_, (corrId, entId, cmd)) = case cmd of
       Cmd SProxiedClient command -> processProxiedCmd (corrId, entId, command)
       Cmd SSender command -> case command of
         SKEY k -> withQueue $ \q qr -> checkMode QMMessaging qr $ secureQueue_ q k
         SEND flags msgBody -> response <$> withQueue_ False err (sendMessage flags msgBody)
       Cmd SIdleClient PING -> pure $ response (corrId, NoEntity, PONG)
-      Cmd SProxyService (RFWD encBlock) -> response . (corrId,NoEntity,) <$> processForwardedCommand encBlock
+      Cmd SProxyService (RFWD encBlock) -> (response . (corrId, NoEntity,) =<<) <$> processForwardedCommand encBlock
+      Cmd SResolver (RSLV d) -> rslvNamesEnv >>= \case
+        Nothing -> pure $ response (corrId, NoEntity, ERR (NAME NO_RESOLVER))
+        Just nenv -> forkCmd serverResolverConcurrency corrId NoEntity (resolveNameMsg nenv d)
       Cmd SSenderLink command -> case command of
         LKEY k -> withQueue $ \q qr -> checkMode QMMessaging qr $ secureQueue_ q k $>> getQueueLink_ q qr
         LGET -> withQueue $ \q qr -> checkContact qr $ getQueueLink_ q qr
@@ -1943,7 +1977,7 @@ client
 
         sendMessage :: MsgFlags -> MsgBody -> StoreQueue s -> QueueRec -> M s (Transmission BrokerMsg)
         sendMessage msgFlags msgBody q qr
-          | B.length msgBody > maxMessageLength clntVersion = do
+          | B.length msgBody > maxMessageLength = do
               stats <- asks serverStats
               incStat $ msgSentLarge stats
               pure $ err LARGE_MSG
@@ -2083,8 +2117,8 @@ client
                   encNMsgMeta = C.cbEncrypt rcvNtfDhSecret ntfNonce (smpEncode msgMeta) 128
               pure $ MsgNtf {ntfMsgId = msgId, ntfTs = msgTs, ntfNonce, ntfEncMeta = fromRight "" encNMsgMeta}
 
-        processForwardedCommand :: EncFwdTransmission -> M s BrokerMsg
-        processForwardedCommand (EncFwdTransmission s) = fmap (either ERR RRES) . runExceptT $ do
+        processForwardedCommand :: EncFwdTransmission -> M s (Maybe BrokerMsg)
+        processForwardedCommand (EncFwdTransmission s) = fmap (either (Just . ERR) id) . runExceptT $ do
           THAuthServer {serverPrivKey, sessSecret'} <- maybe (throwE $ transportErr TENoServerAuth) pure (thAuth thParams')
           sessSecret <- maybe (throwE $ transportErr TENoServerAuth) pure sessSecret'
           let proxyNonce = C.cbNonce $ bs corrId
@@ -2099,28 +2133,31 @@ client
             t :| [] -> pure $ tDecodeServer clntTHParams t
             _ -> throwE BLOCK
           let clntThAuth = Just $ THAuthServer {serverPrivKey, peerClientService = Nothing, sessSecret' = Just clientSecret}
-          -- process forwarded command
-          r <-
-            lift (rejectOrVerify clntThAuth t') >>= \case
-              Left r -> pure r
-              -- rejectOrVerify filters allowed commands, no need to repeat it here.
-              -- INTERNAL is used because processCommand never returns Nothing for sender commands (could be extracted for better types).
-              -- `fst` removes empty message that is only returned for `SUB` command
-              Right t''@(_, (corrId', entId', _)) -> maybe (corrId', entId', ERR INTERNAL) fst <$> lift (processCommand Nothing fwdVersion (Right (M.empty, M.empty, M.empty)) t'')
-          -- encode response
-          r' <- case batchTransmissions clntTHParams [Right (Nothing, encodeTransmission clntTHParams r)] of
-            [] -> throwE INTERNAL -- at least 1 item is guaranteed from NonEmpty/Right
-            TBError _ _ : _ -> throwE BLOCK
-            TBTransmission b' _ : _ -> pure b'
-            TBTransmissions b' _ _ : _ -> pure b'
-          -- encrypt to client
-          r2 <- liftEitherWith (const BLOCK) $ EncResponse <$> C.cbEncrypt clientSecret (C.reverseNonce clientNonce) r' paddedProxiedTLength
-          -- encrypt to proxy
-          let fr = FwdResponse {fwdCorrId, fwdResponse = r2}
-              r3 = EncFwdResponse $ C.cbEncryptNoPad sessSecret (C.reverseNonce proxyNonce) (smpEncode fr)
+              encodeResp r = do
+                r' <- case batchTransmissions clntTHParams [Right (Nothing, encodeTransmission clntTHParams r)] of
+                  [] -> throwE INTERNAL -- at least 1 item is guaranteed from NonEmpty/Right
+                  TBError _ _ : _ -> throwE BLOCK
+                  TBTransmission b' _ : _ -> pure b'
+                  TBTransmissions b' _ _ : _ -> pure b'
+                r2 <- liftEitherWith (const BLOCK) $ EncResponse <$> C.cbEncrypt clientSecret (C.reverseNonce clientNonce) r' paddedProxiedTLength
+                let fr = FwdResponse {fwdCorrId, fwdResponse = r2}
+                pure $ RRES $ EncFwdResponse $ C.cbEncryptNoPad sessSecret (C.reverseNonce proxyNonce) (smpEncode fr)
+          -- the inner response, or Nothing if forked (RSLV).
+          r_ <- lift (rejectOrVerify clntThAuth t') >>= \case
+            -- rejectOrVerify filters allowed commands, no need to repeat it here.
+            Left r -> pure $ Just r
+            Right t''@(_, (corrId', entId', cmd')) -> case cmd' of
+              Cmd SResolver (RSLV d) -> lift $ rslvNamesEnv >>= \case
+                Nothing -> pure $ Just (corrId', entId', ERR (NAME NO_RESOLVER))
+                Just nenv -> forkCmd serverResolverConcurrency corrId NoEntity $ do
+                  msg <- resolveNameMsg nenv d
+                  either ERR id <$> runExceptT (encodeResp (corrId', entId', msg))
+              -- INTERNAL because processCommand never returns Nothing for sender commands;
+              -- `fst` drops the empty message only returned for SUB.
+              _ -> Just . maybe (corrId', entId', ERR INTERNAL) fst <$> lift (processCommand Nothing (Right (M.empty, M.empty, M.empty)) t'')
           stats <- asks serverStats
           incStat $ pMsgFwdsRecv stats
-          pure r3
+          traverse encodeResp r_
           where
             rejectOrVerify :: Maybe (THandleAuth 'TServer) -> SignedTransmissionOrError ErrorType Cmd -> M s (VerifiedTransmissionOrError s)
             rejectOrVerify clntThAuth = \case
@@ -2134,6 +2171,7 @@ client
                     Cmd SSender (SKEY _) -> True
                     Cmd SSenderLink (LKEY _) -> True
                     Cmd SSenderLink LGET -> True
+                    Cmd SResolver (RSLV _) -> True
                     _ -> False
                   verified = \case
                     VRVerified q -> Right (q, t'')
@@ -2468,4 +2506,4 @@ restoreServerStats msgStats_ ntfStats = asks (serverStatsBackupFile . config) >>
           logNote $ "error restoring server stats: " <> T.pack e
           liftIO exitFailure
     compareCounts name statsCnt storeCnt =
-      when (statsCnt /= storeCnt) $ logWarn $ name <> " count differs: stats: " <> tshow statsCnt <> ", store: " <> tshow storeCnt
+      when (statsCnt /= storeCnt) $ logWarn $ name <> " count differs: stats: " <> tshow statsCnt <> ", store: " <> tshow storeCnt

src/Simplex/Messaging/Server/Env/STM.hs

@@ -67,6 +67,7 @@ module Simplex.Messaging.Server.Env.STM
     defaultNtfExpiration,
     defaultInactiveClientExpiration,
     defaultProxyClientConcurrency,
+    defaultNameResolverConcurrency,
     defaultMaxJournalMsgCount,
     defaultMaxJournalStateLines,
     defaultIdleQueueInterval,
@@ -115,6 +116,7 @@ import Simplex.Messaging.Server.Information
 import Simplex.Messaging.Server.MsgStore.Journal
 import Simplex.Messaging.Server.MsgStore.STM
 import Simplex.Messaging.Server.MsgStore.Types
+import Simplex.Messaging.Server.Names (NamesConfig (..), NamesEnv, newNamesEnv, pingEndpoint)
 import Simplex.Messaging.Server.NtfStore
 import Simplex.Messaging.Server.QueueStore
 import Simplex.Messaging.Server.QueueStore.Postgres.Config
@@ -128,7 +130,7 @@ import Simplex.Messaging.TMap (TMap)
 import qualified Simplex.Messaging.TMap as TM
 import Simplex.Messaging.Transport (ASrvTransport, SMPVersion, THandleParams, TransportPeer (..), VersionRangeSMP)
 import Simplex.Messaging.Transport.Server
-import Simplex.Messaging.Util (ifM, whenM, ($>>=))
+import Simplex.Messaging.Util (ifM, tshow, whenM, ($>>=))
 import System.Directory (doesFileExist)
 import System.Exit (exitFailure)
 import System.IO (IOMode (..))
@@ -197,6 +199,13 @@ data ServerConfig s = ServerConfig
     smpAgentCfg :: SMPClientAgentConfig,
     allowSMPProxy :: Bool, -- auth is the same with `newQueueBasicAuth`
     serverClientConcurrency :: Int,
+    -- | max concurrent name resolutions per connection, enforced in forkCmd.
+    -- Much higher than serverClientConcurrency: forwarded RSLVs from many clients
+    -- aggregate over a single proxy->relay connection (only servers send proxied
+    -- requests), so bounding them by the per-client limit would throttle unduly.
+    serverResolverConcurrency :: Int,
+    -- | public-namespace resolver config; Nothing disables the names role
+    namesConfig :: Maybe NamesConfig,
     -- | server public information
     information :: Maybe ServerPublicInfo,
     startOptions :: StartOptions
@@ -243,6 +252,9 @@ defaultInactiveClientExpiration =
 defaultProxyClientConcurrency :: Int
 defaultProxyClientConcurrency = 32
 
+defaultNameResolverConcurrency :: Int
+defaultNameResolverConcurrency = 1000
+
 journalMsgStoreDepth :: Int
 journalMsgStoreDepth = 5
 
@@ -272,7 +284,8 @@ data Env s = Env
     serverStats :: ServerStats,
     sockets :: TVar [(ServiceName, SocketState)],
     clientSeq :: TVar ClientId,
-    proxyAgent :: ProxyAgent -- senders served on this proxy
+    proxyAgent :: ProxyAgent, -- senders served on this proxy
+    namesEnv :: Maybe NamesEnv -- public-namespace resolver, present when [NAMES] enable: on
   }
 
 msgStore :: Env s -> s
@@ -558,7 +571,7 @@ newProhibitedSub = do
   return Sub {subThread = ProhibitSub, delivered}
 
 newEnv :: ServerConfig s -> IO (Env s)
-newEnv config@ServerConfig {smpCredentials, httpCredentials, serverStoreCfg, smpAgentCfg, information, messageExpiration, idleQueueInterval, msgQueueQuota, maxJournalMsgCount, maxJournalStateLines} = do
+newEnv config@ServerConfig {smpCredentials, httpCredentials, serverStoreCfg, smpAgentCfg, information, messageExpiration, idleQueueInterval, msgQueueQuota, maxJournalMsgCount, maxJournalStateLines, namesConfig} = do
   serverActive <- newTVarIO True
   server <- newServer
   msgStore_ <- case serverStoreCfg of
@@ -603,6 +616,16 @@ newEnv config@ServerConfig {smpCredentials, httpCredentials, serverStoreCfg, smp
   sockets <- newTVarIO []
   clientSeq <- newTVarIO 0
   proxyAgent <- newSMPProxyAgent smpAgentCfg random
+  namesEnv <- forM namesConfig $ \nc -> do
+    logInfo $ "[NAMES] resolver enabled, endpoint=" <> T.pack (resolverEndpoint nc)
+    env <- newNamesEnv nc
+    -- Probe the endpoint at startup. Don't exitFailure: a flapping network or a
+    -- resolver host coming up minutes after smp-server should not block the
+    -- server. Log so operators can spot it.
+    pingEndpoint env >>= \case
+      Right _ -> logInfo "[NAMES] endpoint probe ok"
+      Left e -> logWarn $ "[NAMES] endpoint probe failed (server will still start, RSLV will return ERR (NAME ...) until reachable): " <> tshow e
+    pure env
   pure
     Env
       { serverActive,
@@ -618,7 +641,8 @@ newEnv config@ServerConfig {smpCredentials, httpCredentials, serverStoreCfg, smp
         serverStats,
         sockets,
         clientSeq,
-        proxyAgent
+        proxyAgent,
+        namesEnv
       }
   where
     loadStoreLog :: StoreQueueClass q => (RecipientId -> QueueRec -> IO q) -> FilePath -> STMQueueStore q -> IO ()

src/Simplex/Messaging/Server/Information.hs

@@ -26,7 +26,6 @@ import qualified Data.Attoparsec.ByteString.Char8 as A
 import Data.Int (Int64)
 import Data.Maybe (isJust)
 import Data.Text (Text)
-import Simplex.Messaging.Agent.Protocol (ConnectionLink, ConnectionMode (..))
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Parsers (defaultJSON, dropPrefix, enumJSON)
 
@@ -112,7 +111,7 @@ data Entity = Entity {name :: Text, country :: Maybe Text}
   deriving (Show)
 
 data ServerContactAddress = ServerContactAddress
-  { simplex :: Maybe (ConnectionLink 'CMContact),
+  { simplex :: Maybe Text,
     email :: Maybe Text, -- it is recommended that it matches DNS email address, if either is present
     pgp :: Maybe PGPKey
   }

src/Simplex/Messaging/Server/Main.hs

@@ -34,6 +34,7 @@ module Simplex.Messaging.Server.Main
     simplexmqSource,
     serverPublicInfo,
     validCountryValue,
+    validateUrl,
     printSourceCode,
     cliCommandP,
     strParse,
@@ -50,7 +51,7 @@ import Data.Char (isAlpha, isAscii, toUpper)
 import Data.Either (fromRight)
 import Data.Functor (($>))
 import Data.Ini (Ini, lookupValue, readIniFile)
-import Data.List (find, isPrefixOf)
+import Data.List (dropWhileEnd, find, isPrefixOf)
 import qualified Data.List.NonEmpty as L
 import Data.Maybe (fromMaybe, isJust, isNothing)
 import Data.Text (Text)
@@ -58,7 +59,7 @@ import qualified Data.Text as T
 import Data.Text.Encoding (decodeLatin1, encodeUtf8)
 import qualified Data.Text.IO as T
 import Options.Applicative
-import Simplex.Messaging.Agent.Protocol (ConnectionLink (..), connReqUriP')
+import Simplex.Messaging.Agent.Protocol (ConnectionLink (..), ConnectionMode (..), connReqUriP')
 import Simplex.Messaging.Agent.Store.Postgres.Options (DBOpts (..))
 import Simplex.Messaging.Agent.Store.Shared (MigrationConfirmation (..))
 import Simplex.Messaging.Client (HostMode (..), NetworkConfig (..), ProtocolClientConfig (..), SMPWebPortServers (..), SocksMode (..), defaultNetworkConfig, textToHostMode)
@@ -66,6 +67,7 @@ import Simplex.Messaging.Client.Agent (SMPClientAgentConfig (..), defaultSMPClie
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Parsers (parseAll)
+import Network.URI (URI (..), URIAuth (..), parseAbsoluteURI)
 import Simplex.Messaging.Protocol (BasicAuth (..), ProtoServerWithAuth (ProtoServerWithAuth), pattern SMPServer)
 import Simplex.Messaging.Server (AttachHTTP, exportMessages, importMessages, printMessageStats, runSMPServer)
 import Simplex.Messaging.Server.CLI
@@ -76,13 +78,14 @@ import Simplex.Messaging.Server.Main.Init
 import Simplex.Messaging.Server.Web (EmbeddedWebParams (..), WebHttpsParams (..))
 import Simplex.Messaging.Server.MsgStore.Journal (JournalMsgStore (..), QStoreCfg (..), stmQueueStore)
 import Simplex.Messaging.Server.MsgStore.Types (MsgStoreClass (..), SQSType (..), SMSType (..), newMsgStore)
+import Simplex.Messaging.Server.Names (NamesConfig (..), RpcAuth (..))
 import Simplex.Messaging.Server.QueueStore.Postgres.Config
 import Simplex.Messaging.Server.StoreLog.ReadWrite (readQueueStore)
 import Simplex.Messaging.Transport (supportedProxyClientSMPRelayVRange, alpnSupportedSMPHandshakes, supportedServerSMPRelayVRange)
 import Simplex.Messaging.Transport.Client (TransportHost (..), defaultSocksProxy)
 import Simplex.Messaging.Transport.HTTP2 (httpALPN)
 import Simplex.Messaging.Transport.Server (ServerCredentials (..), mkTransportServerConfig)
-import Simplex.Messaging.Util (eitherToMaybe, ifM)
+import Simplex.Messaging.Util (eitherToMaybe, ifM, safeDecodeUtf8)
 import System.Directory (createDirectoryIfMissing, doesDirectoryExist, doesFileExist)
 import System.Exit (exitFailure)
 import System.FilePath (combine)
@@ -601,10 +604,13 @@ smpServerCLI_ generateSite serveStaticFiles attachStaticFiles cfgPath logPath =
                               }
                         },
                     ownServerDomains = either (const []) textToOwnServers $ lookupValue "PROXY" "own_server_domains" ini,
+                    msgQSize = Nothing, -- to prevent accumulation of late responses, and deadlocks in SMP proxy
                     persistErrorInterval = 30 -- seconds
                   },
               allowSMPProxy = True,
               serverClientConcurrency = readIniDefault defaultProxyClientConcurrency "PROXY" "client_concurrency" ini,
+              serverResolverConcurrency = readIniDefault defaultNameResolverConcurrency "NAMES" "resolver_concurrency" ini,
+              namesConfig = readNamesConfig ini,
               information = serverPublicInfo ini,
               startOptions
             }
@@ -781,12 +787,13 @@ serverPublicInfo ini = serverInfo <$!> infoValue "source_code"
         <$!> infoValue nameField
     countryValue field = (either error id . validCountryValue (T.unpack field) . T.unpack) <$!> infoValue field
     iniContacts simplexField emailField pgpKeyUriField pgpKeyFingerprintField =
-      let simplex = either error id . parseAll linkP . encodeUtf8 <$!> eitherToMaybe (lookupValue "INFORMATION" simplexField ini)
+      let addr :: Maybe (ConnectionLink 'CMContact) = either error id . parseAll linkP . encodeUtf8 <$!> eitherToMaybe (lookupValue "INFORMATION" simplexField ini)
+          simplex = safeDecodeUtf8 . strEncode <$> addr
           linkP = CLFull <$> connReqUriP' Nothing <|> CLShort <$> strP
           email = infoValue emailField
           pkURI_ = infoValue pgpKeyUriField
           pkFingerprint_ = infoValue pgpKeyFingerprintField
-       in case (simplex, email, pkURI_, pkFingerprint_) of
+       in case (addr, email, pkURI_, pkFingerprint_) of
             (Nothing, Nothing, Nothing, _) -> Nothing
             (Nothing, Nothing, _, Nothing) -> Nothing
             (_, _, pkURI, pkFingerprint) -> Just ServerContactAddress {simplex, email, pgp = PGPKey <$> pkURI <*> pkFingerprint}
@@ -796,6 +803,64 @@ validCountryValue field s
   | length s == 2 && all (\c -> isAscii c && isAlpha c) s = Right $ T.pack $ map toUpper s
   | otherwise = Left $ "Use ISO3166 2-letter code for " <> field
 
+readNamesConfig :: Ini -> Maybe NamesConfig
+readNamesConfig ini
+  | not enabled = Nothing
+  | otherwise =
+      let resolverAuth_ = either (error . ("[NAMES] resolver_auth: " <>)) Just . parseRpcAuth =<< eitherToMaybe (lookupValue "NAMES" "resolver_auth" ini)
+          endpoint = requiredText "resolver_endpoint"
+       in Just
+            NamesConfig
+              { resolverEndpoint = either (error . ("[NAMES] resolver_endpoint: " <>)) id (validateUrl endpoint resolverAuth_),
+                resolverAuth = resolverAuth_,
+                resolverTimeoutMs = boundedIniInt 3000 100 60000 "resolver_timeout_ms",
+                resolverMaxResponseBytes = boundedIniInt 16000 1024 16000 "resolver_max_response_bytes"
+              }
+  where
+    enabled = fromMaybe False (iniOnOff "NAMES" "enable" ini)
+    requiredText key =
+      either (error . (("[NAMES] " <> T.unpack key <> " is required: ") <>)) id $
+        lookupValue "NAMES" key ini
+    boundedIniInt def floor_ ceiling_ key = case lookupValue "NAMES" key ini of
+      Left _ -> def
+      Right raw -> case readMaybe (T.unpack (T.strip raw)) of
+        Nothing ->
+          error $ "[NAMES] " <> T.unpack key <> ": not an integer (got " <> show raw <> ")"
+        Just n
+          | n >= floor_ && n <= ceiling_ -> n
+          | otherwise ->
+              error $ "[NAMES] " <> T.unpack key <> " must be in [" <> show floor_ <> ".." <> show ceiling_ <> "] (got " <> show n <> ")"
+
+-- | Validate the resolver_endpoint URL: it must be an absolute http(s) URL with a host.
+-- http + resolver_auth to a non-loopback host is rejected.
+validateUrl :: Text -> Maybe RpcAuth -> Either String String
+validateUrl url auth_ = do
+  let s = T.unpack url
+  uri <- maybe (Left "not an absolute URI") Right $ parseAbsoluteURI s
+  let scheme = uriScheme uri
+  unless (scheme == "http:" || scheme == "https:") $ Left "scheme must be http or https"
+  ua <- maybe (Left "missing host") Right (uriAuthority uri)
+  let host = uriRegName ua
+  when (null host) $ Left "empty host"
+  unless (null (uriUserInfo ua)) $ Left "userinfo (user:pass@) not allowed; put credentials in resolver_auth"
+  when (scheme == "http:" && isJust auth_ && not (isLoopback host)) $
+    Left "http with resolver_auth on a non-loopback host not allowed (the Authorization header would travel in cleartext); use https, or drop resolver_auth"
+  Right (dropWhileEnd (== '/') s)
+  where
+    isLoopback h = h == "localhost" || h == "127.0.0.1" || h == "[::1]" || h == "0.0.0.0"
+
+-- | Parse an rpc_auth INI value. Scheme keyword is case-insensitive so
+-- "Bearer <token>" / "BEARER <token>" (Caddy / RFC 7235 convention) work
+-- as well as the lowercase form.
+parseRpcAuth :: Text -> Either String RpcAuth
+parseRpcAuth t = case T.words t of
+  [scheme, tok] | T.toLower scheme == "bearer" -> Right $ AuthBearer tok
+  [scheme, up] | T.toLower scheme == "basic" -> case T.breakOn ":" up of
+    (u, rest)
+      | not (T.null u) && ":" `T.isPrefixOf` rest -> Right $ AuthBasic u (T.drop 1 rest)
+    _ -> Left "basic auth expects user:password"
+  _ -> Left "expected `bearer <token>` or `basic <user>:<pass>`"
+
 printSourceCode :: Maybe Text -> IO ()
 printSourceCode = \case
   Just sourceCode -> T.putStrLn $ "Server source code: " <> sourceCode

src/Simplex/Messaging/Server/Main/Init.hs

@@ -154,6 +154,22 @@ iniFileContent cfgPath logPath opts host basicAuth controlPortPwds =
         \# socks_mode = onion\n\n\
         \# Limit number of threads a client can spawn to process proxy commands in parrallel.\n"
     <> ("# client_concurrency = " <> tshow defaultProxyClientConcurrency)
+    <> "\n\n\
+        \[NAMES]\n\
+        \# Public-namespace resolution via the snrc-resolve.py REST resolver.\n\
+        \# Operator runs the resolver alongside smp-server (default port 8000)\n\
+        \# with its own Ethereum JSON-RPC endpoint configured in resolver.toml.\n\
+        \enable: off\n\
+        \# Same-host:\n\
+        \# resolver_endpoint: http://127.0.0.1:8000\n\
+        \# Resolver behind TLS reverse proxy:\n\
+        \# resolver_endpoint: https://names.simplex.chat:443\n\
+        \# resolver_auth: basic <username>:<password>\n\
+        \# resolver_timeout_ms: 3000\n\
+        \# resolver_max_response_bytes: 16000\n\
+        \# Max concurrent name resolutions per connection (forwarded RSLVs from many\n\
+        \# clients share one proxy connection, so this is much higher than PROXY client_concurrency).\n"
+    <> ("# resolver_concurrency = " <> tshow defaultNameResolverConcurrency)
     <> "\n\n\
         \[INACTIVE_CLIENTS]\n\
         \# TTL and interval to check inactive clients\n\

src/Simplex/Messaging/Server/Names.hs

@@ -0,0 +1,84 @@
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE StrictData #-}
+
+module Simplex.Messaging.Server.Names
+  ( NamesConfig (..),
+    RpcAuth (..),
+    NamesEnv (..),
+    newNamesEnv,
+    closeNamesEnv,
+    pingEndpoint,
+    resolveName,
+  )
+where
+
+import qualified Control.Exception as E
+import Control.Logger.Simple (logError)
+import Data.Bifunctor (first)
+import Data.Maybe (fromMaybe)
+import qualified Data.Text as T
+import Simplex.Messaging.Protocol (NameErrorType (..), NameRecord)
+import Simplex.Messaging.Server.Names.HttpResolver
+  ( ResolverEnv,
+    ResolverError (..),
+    RpcAuth (..),
+    closeResolverEnv,
+    healthHttp,
+    newResolverEnv,
+    resolveHttp,
+  )
+import Simplex.Messaging.SimplexName (SimplexDomain, fullDomainName)
+import System.Timeout (timeout)
+
+data NamesConfig = NamesConfig
+  { resolverEndpoint :: String,
+    resolverAuth :: Maybe RpcAuth,
+    resolverTimeoutMs :: Int,
+    resolverMaxResponseBytes :: Int
+  }
+  deriving (Show)
+
+data NamesEnv = NamesEnv
+  { config :: NamesConfig,
+    resolverEnv :: ResolverEnv
+  }
+
+newNamesEnv :: NamesConfig -> IO NamesEnv
+newNamesEnv config = do
+  resolverEnv <- newResolverEnv (resolverEndpoint config) (resolverAuth config) (resolverTimeoutMs config) (resolverMaxResponseBytes config)
+  pure NamesEnv {config, resolverEnv}
+
+closeNamesEnv :: NamesEnv -> IO ()
+closeNamesEnv NamesEnv {resolverEnv} = closeResolverEnv resolverEnv
+
+pingEndpoint :: NamesEnv -> IO (Either ResolverError ())
+pingEndpoint NamesEnv {resolverEnv, config} =
+  fromMaybe (Left ResolverTimeout) <$> timeout (resolverTimeoutMs config * 1000) (healthHttp resolverEnv)
+
+resolveName :: NamesEnv -> SimplexDomain -> IO (Either NameErrorType NameRecord)
+resolveName env d = do
+  r <- E.try (timeout (resolverTimeoutMs (config env) * 1000) (fetch env d))
+  case r of
+    Right result -> pure (fromMaybe (Left (RESOLVER "timeout")) result)
+    Left e
+      | Just (_ :: E.SomeAsyncException) <- E.fromException e -> E.throwIO e
+      | otherwise -> do
+          logError $ "[NAMES] resolver fetch raised " <> T.pack (E.displayException e)
+          pure (Left (RESOLVER "resolver error"))
+
+fetch :: NamesEnv -> SimplexDomain -> IO (Either NameErrorType NameRecord)
+fetch NamesEnv {resolverEnv} d =
+  first mapResolverError <$> resolveHttp resolverEnv (fullDomainName d)
+
+mapResolverError :: ResolverError -> NameErrorType
+mapResolverError = \case
+  HttpStatusErr 404 -> NOT_FOUND
+  HttpStatusErr 400 -> NOT_FOUND
+  HttpStatusErr code -> RESOLVER ("HTTP " <> T.pack (show code))
+  HttpFailure _ -> RESOLVER "transport failure"
+  BodyTooLarge -> RESOLVER "response too large"
+  InvalidJson _ -> RESOLVER "invalid response"
+  ResolverTimeout -> RESOLVER "timeout"

src/Simplex/Messaging/Server/Names/HttpResolver.hs

@@ -0,0 +1,144 @@
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE StrictData #-}
+
+-- | HTTP transport for the public-namespace resolver.
+--
+-- The Python REST resolver (see scripts/resolver/snrc-resolve.py) exposes
+--
+--   GET /resolve/<name>   -> 200 with a NameRecord JSON document
+--                            404 / 400 for unknown names / TLDs
+--                            502 for upstream RPC failures
+--   GET /health           -> 200 when the resolver process is ready
+--
+-- Boundary properties:
+--   * Response body read with `brReadSome maxResponseBytes` — adversarial
+--     endpoints cannot exhaust memory with multi-GB bodies.
+--   * `redirectCount = 0` — a compromised resolver cannot bounce credentials
+--     to a private-IP target (SSRF amplification on top of the URL validation
+--     performed at config load in Server.Main.validateUrl).
+--   * Authorization header attached only when configured.
+module Simplex.Messaging.Server.Names.HttpResolver
+  ( RpcAuth (..),
+    ResolverEnv,
+    ResolverError (..),
+    newResolverEnv,
+    closeResolverEnv,
+    resolveHttp,
+    healthHttp,
+  )
+where
+
+import qualified Control.Exception as E
+import qualified Data.Aeson as J
+import Data.Bifunctor (first)
+import qualified Data.ByteArray.Encoding as BAE
+import Data.ByteString.Char8 (ByteString)
+import qualified Data.ByteString.Char8 as B
+import qualified Data.ByteString.Lazy as BL
+import Data.Text (Text)
+import Data.Text.Encoding (encodeUtf8)
+import Network.HTTP.Client
+  ( HttpException,
+    Manager,
+    ManagerSettings (..),
+    brReadSome,
+    parseRequest,
+    redirectCount,
+    requestHeaders,
+    responseBody,
+    responseStatus,
+    responseTimeoutMicro,
+    withResponse,
+  )
+import qualified Network.HTTP.Client as HC
+import Network.HTTP.Client.TLS (tlsManagerSettings)
+import qualified Network.HTTP.Types as HT
+import Network.HTTP.Types.URI (urlEncode)
+import Simplex.Messaging.Names.Record (NameRecord)
+
+data RpcAuth = AuthBearer Text | AuthBasic Text Text
+
+-- | Redacts the bearer token / basic-auth password so an accidental
+-- `show` / `tshow` on NamesConfig never lands secrets in logs.
+instance Show RpcAuth where
+  show (AuthBearer _) = "AuthBearer <redacted>"
+  show (AuthBasic u _) = "AuthBasic " <> show u <> " <redacted>"
+
+data ResolverEnv = ResolverEnv
+  { manager :: Manager,
+    baseUrl :: String,
+    authHdr :: [HT.Header],
+    timeoutMicro :: Int,
+    maxResponseBytes :: Int
+  }
+
+data ResolverError
+  = HttpFailure HttpException
+  | HttpStatusErr Int
+  | BodyTooLarge
+  | InvalidJson String
+  | ResolverTimeout
+  deriving (Show)
+
+newResolverEnv :: String -> Maybe RpcAuth -> Int -> Int -> IO ResolverEnv
+newResolverEnv baseUrl auth_ timeoutMs maxResponseBytes = do
+  manager <- HC.newManager tlsManagerSettings {managerConnCount = 10}
+  pure
+    ResolverEnv
+      { manager,
+        baseUrl,
+        authHdr = maybe [] (pure . authHeader) auth_,
+        timeoutMicro = timeoutMs * 1000,
+        maxResponseBytes
+      }
+
+-- | http-client's `closeManager` is a deprecated no-op since 0.5; the
+-- manager is released by the GC finalizer on its internal state. Hook kept
+-- as a future-cleanup seam.
+closeResolverEnv :: ResolverEnv -> IO ()
+closeResolverEnv _ = pure ()
+
+authHeader :: RpcAuth -> HT.Header
+authHeader = \case
+  AuthBearer tok -> ("Authorization", "Bearer " <> encodeUtf8 tok)
+  AuthBasic u p ->
+    let encoded = BAE.convertToBase BAE.Base64 (encodeUtf8 u <> ":" <> encodeUtf8 p) :: ByteString
+     in ("Authorization", "Basic " <> encoded)
+
+-- | GET <baseUrl>/resolve/<percent-encoded name>, decoding the 200 body
+-- directly into a NameRecord in one pass (no intermediate Aeson Value). The
+-- name is percent-encoded (every non-unreserved byte per RFC 3986): the
+-- resolver expects raw labels, so slashes/punctuation must not alter the path.
+resolveHttp :: ResolverEnv -> Text -> IO (Either ResolverError NameRecord)
+resolveHttp env name =
+  (>>= first InvalidJson . J.eitherDecodeStrict . BL.toStrict)
+    <$> httpGet env ("/resolve/" <> B.unpack (urlEncode True (encodeUtf8 name)))
+
+-- | GET <baseUrl>/health; success = reachable with status < 400. The body is
+-- size-capped but NOT decoded — the probe only checks reachability.
+healthHttp :: ResolverEnv -> IO (Either ResolverError ())
+healthHttp env = (() <$) <$> httpGet env "/health"
+
+-- | GET <baseUrl><path>, returning the response body bytes on status < 400
+-- within the size cap. Redirects are disabled and Authorization is attached
+-- only when configured.
+httpGet :: ResolverEnv -> String -> IO (Either ResolverError BL.ByteString)
+httpGet ResolverEnv {manager, baseUrl, authHdr, timeoutMicro, maxResponseBytes} path = do
+  req0 <- parseRequest (baseUrl <> path)
+  let req =
+        req0
+          { redirectCount = 0,
+            requestHeaders = ("Accept", "application/json") : authHdr,
+            HC.responseTimeout = responseTimeoutMicro timeoutMicro
+          }
+  result <- E.try $ withResponse req manager $ \res -> do
+    let status = HT.statusCode (responseStatus res)
+    if status >= 400
+      then pure (Left (HttpStatusErr status))
+      else do
+        bs <- brReadSome (responseBody res) (maxResponseBytes + 1)
+        pure $ if BL.length bs > fromIntegral maxResponseBytes then Left BodyTooLarge else Right bs
+  pure (either (Left . HttpFailure) id result)

src/Simplex/Messaging/Server/Prometheus.hs

@@ -59,7 +59,7 @@ data RTSubscriberMetrics = RTSubscriberMetrics
 {-# FOURMOLU_DISABLE\n#-}
 prometheusMetrics :: ServerMetrics -> RealTimeMetrics -> UTCTime -> Text
 prometheusMetrics sm rtm ts =
-  time <> queues <> subscriptions <> messages <> ntfMessages <> ntfs <> relays <> services <> info
+  time <> queues <> subscriptions <> messages <> ntfMessages <> ntfs <> relays <> services <> names <> info
   where
     ServerMetrics {statsData, activeQueueCounts = ps, activeNtfCounts = psNtf, entityCounts, rtsOptions} = sm
     RealTimeMetrics
@@ -128,7 +128,8 @@ prometheusMetrics sm rtm ts =
         _rcvServicesSubDuplicate,
         _qCount,
         _msgCount,
-        _ntfCount
+        _ntfCount,
+        _rslvStats
       } = statsData
     time =
       "# Recorded at: " <> T.pack (iso8601Show ts) <> "\n\
@@ -459,6 +460,31 @@ prometheusMetrics sm rtm ts =
       \# TYPE simplex_smp_" <> pfx <> "_services_sub_fewer_total gauge\n\
       \simplex_smp_" <> pfx <> "_services_sub_fewer_total " <> mshow (_srvSubFewerTotal ss) <> "\n# " <> pfx <> ".srvSubFewerTotal\n\
       \\n"
+    names =
+      let NameResolverStatsData {_rslvReqs, _rslvSucc, _rslvNotFound, _rslvResolverErrs, _rslvDisabled} = _rslvStats
+       in "# Names\n\
+          \# -----\n\
+          \\n\
+          \# HELP simplex_smp_names_reqs Total RSLV requests forwarded to this server.\n\
+          \# TYPE simplex_smp_names_reqs counter\n\
+          \simplex_smp_names_reqs " <> mshow _rslvReqs <> "\n# rslvReqs\n\
+          \\n\
+          \# HELP simplex_smp_names_success NameRecord successfully resolved and returned.\n\
+          \# TYPE simplex_smp_names_success counter\n\
+          \simplex_smp_names_success " <> mshow _rslvSucc <> "\n# rslvSucc\n\
+          \\n\
+          \# HELP simplex_smp_names_not_found Name not registered (resolver returned 404 / 400).\n\
+          \# TYPE simplex_smp_names_not_found counter\n\
+          \simplex_smp_names_not_found " <> mshow _rslvNotFound <> "\n# rslvNotFound\n\
+          \\n\
+          \# HELP simplex_smp_names_resolver_errs Resolver backend errors (HTTP 5xx, transport, decode, or timeout).\n\
+          \# TYPE simplex_smp_names_resolver_errs counter\n\
+          \simplex_smp_names_resolver_errs " <> mshow _rslvResolverErrs <> "\n# rslvResolverErrs\n\
+          \\n\
+          \# HELP simplex_smp_names_disabled RSLV requests rejected because no resolver is configured (names role off).\n\
+          \# TYPE simplex_smp_names_disabled counter\n\
+          \simplex_smp_names_disabled " <> mshow _rslvDisabled <> "\n# rslvDisabled\n\
+          \\n"
     info =
       "# Info\n\
       \# ----\n\

src/Simplex/Messaging/Server/QueueStore/Postgres.hs

@@ -342,7 +342,7 @@ instance StoreQueueClass q => QueueStoreClass q (PostgresQueueStore q) where
     withQueueRec sq "secureQueue" $ \q -> do
       verify q
       assertUpdated $ withDB' "secureQueue" st $ \db ->
-        DB.execute db "UPDATE msg_queues SET sender_key = ? WHERE recipient_id = ? AND deleted_at IS NULL" (sKey, rId)
+        DB.execute db "UPDATE msg_queues SET sender_key = ? WHERE recipient_id = ? AND deleted_at IS NULL AND (sender_key IS NULL OR sender_key = ?)" (sKey, rId, sKey)
       atomically $ writeTVar (queueRec sq) $ Just q {senderKey = Just sKey}
       withLog "secureQueue" st $ \s -> logSecureQueue s rId sKey
     where

src/Simplex/Messaging/Server/QueueStore/STM.hs

@@ -178,10 +178,13 @@ instance StoreQueueClass q => QueueStoreClass q (STMQueueStore q) where
         _ -> pure $ Left AUTH
         where
           addLink = do
-            let !q' = q {queueData = Just (lnkId, d)}
-            writeTVar qr $ Just q'
-            TM.insert lnkId rId $ links st
-            pure $ Right ()
+            TM.lookup lnkId (links st) >>= \case
+              Just rId' | rId' /= rId -> pure $ Left AUTH
+              _ -> do
+                let !q' = q {queueData = Just (lnkId, d)}
+                writeTVar qr $ Just q'
+                TM.insert lnkId rId $ links st
+                pure $ Right ()
 
   deleteQueueLinkData :: STMQueueStore q -> q -> IO (Either ErrorType ())
   deleteQueueLinkData st sq =

src/Simplex/Messaging/Server/Stats.hs

@@ -39,6 +39,13 @@ module Simplex.Messaging.Server.Stats
     setServiceStats,
     emptyTimeBuckets,
     updateTimeBuckets,
+    NameResolverStats (..),
+    NameResolverStatsData (..),
+    newNameResolverStats,
+    newNameResolverStatsData,
+    getNameResolverStatsData,
+    getResetNameResolverStatsData,
+    setNameResolverStats,
   ) where
 
 import Control.Applicative (optional, (<|>))
@@ -123,7 +130,8 @@ data ServerStats = ServerStats
     rcvServicesSubDuplicate :: IORef Int,
     qCount :: IORef Int,
     msgCount :: IORef Int,
-    ntfCount :: IORef Int
+    ntfCount :: IORef Int,
+    rslvStats :: NameResolverStats
   }
 
 data ServerStatsData = ServerStatsData
@@ -184,7 +192,8 @@ data ServerStatsData = ServerStatsData
     _rcvServicesSubDuplicate :: Int,
     _qCount :: Int,
     _msgCount :: Int,
-    _ntfCount :: Int
+    _ntfCount :: Int,
+    _rslvStats :: NameResolverStatsData
   }
   deriving (Show)
 
@@ -248,6 +257,7 @@ newServerStats ts = do
   qCount <- newIORef 0
   msgCount <- newIORef 0
   ntfCount <- newIORef 0
+  rslvStats <- newNameResolverStats
   pure
     ServerStats
       { fromTime,
@@ -307,7 +317,8 @@ newServerStats ts = do
         rcvServicesSubDuplicate,
         qCount,
         msgCount,
-        ntfCount
+        ntfCount,
+        rslvStats
       }
 
 getServerStatsData :: ServerStats -> IO ServerStatsData
@@ -370,6 +381,7 @@ getServerStatsData s = do
   _qCount <- readIORef $ qCount s
   _msgCount <- readIORef $ msgCount s
   _ntfCount <- readIORef $ ntfCount s
+  _rslvStats <- getNameResolverStatsData $ rslvStats s
   pure
     ServerStatsData
       { _fromTime,
@@ -429,7 +441,8 @@ getServerStatsData s = do
         _rcvServicesSubDuplicate,
         _qCount,
         _msgCount,
-        _ntfCount
+        _ntfCount,
+        _rslvStats
       }
 
 -- this function is not thread safe, it is used on server start only
@@ -493,6 +506,7 @@ setServerStats s d = do
   writeIORef (qCount s) $! _qCount d
   writeIORef (msgCount s) $! _msgCount d
   writeIORef (ntfCount s) $! _ntfCount d
+  setNameResolverStats (rslvStats s) $! _rslvStats d
 
 instance StrEncoding ServerStatsData where
   strEncode d =
@@ -557,7 +571,9 @@ instance StrEncoding ServerStatsData where
         "rcvServices:",
         strEncode (_rcvServices d),
         "ntfServices:",
-        strEncode (_ntfServices d)
+        strEncode (_ntfServices d),
+        "rslvStats:",
+        strEncode (_rslvStats d)
       ]
   strP = do
     _fromTime <- "fromTime=" *> strP <* A.endOfLine
@@ -628,6 +644,10 @@ instance StrEncoding ServerStatsData where
     _pMsgFwdsRecv <- opt "pMsgFwdsRecv="
     _rcvServices <- serviceStatsP "rcvServices:"
     _ntfServices <- serviceStatsP "ntfServices:"
+    _rslvStats <-
+      optional ("rslvStats:" <* A.endOfLine) >>= \case
+        Just _ -> strP <* optional A.endOfLine
+        _ -> pure newNameResolverStatsData
     pure
       ServerStatsData
         { _fromTime,
@@ -687,7 +707,8 @@ instance StrEncoding ServerStatsData where
           _rcvServicesSubDuplicate = 0,
           _qCount,
           _msgCount = 0,
-          _ntfCount = 0
+          _ntfCount = 0,
+          _rslvStats
         }
     where
       opt s = A.string s *> strP <* A.endOfLine <|> pure 0
@@ -862,6 +883,89 @@ instance StrEncoding ProxyStatsData where
     _pErrorsOther <- "errorsOther=" *> strP
     pure ProxyStatsData {_pRequests, _pSuccesses, _pErrorsConnect, _pErrorsCompat, _pErrorsOther}
 
+data NameResolverStats = NameResolverStats
+  { rslvReqs :: IORef Int,
+    rslvSucc :: IORef Int,
+    rslvNotFound :: IORef Int,
+    rslvResolverErrs :: IORef Int,
+    rslvDisabled :: IORef Int
+  }
+
+newNameResolverStats :: IO NameResolverStats
+newNameResolverStats = do
+  rslvReqs <- newIORef 0
+  rslvSucc <- newIORef 0
+  rslvNotFound <- newIORef 0
+  rslvResolverErrs <- newIORef 0
+  rslvDisabled <- newIORef 0
+  pure NameResolverStats {rslvReqs, rslvSucc, rslvNotFound, rslvResolverErrs, rslvDisabled}
+
+data NameResolverStatsData = NameResolverStatsData
+  { _rslvReqs :: Int,
+    _rslvSucc :: Int,
+    _rslvNotFound :: Int,
+    _rslvResolverErrs :: Int,
+    _rslvDisabled :: Int
+  }
+  deriving (Show)
+
+newNameResolverStatsData :: NameResolverStatsData
+newNameResolverStatsData =
+  NameResolverStatsData
+    { _rslvReqs = 0,
+      _rslvSucc = 0,
+      _rslvNotFound = 0,
+      _rslvResolverErrs = 0,
+      _rslvDisabled = 0
+    }
+
+getNameResolverStatsData :: NameResolverStats -> IO NameResolverStatsData
+getNameResolverStatsData s = do
+  _rslvReqs <- readIORef $ rslvReqs s
+  _rslvSucc <- readIORef $ rslvSucc s
+  _rslvNotFound <- readIORef $ rslvNotFound s
+  _rslvResolverErrs <- readIORef $ rslvResolverErrs s
+  _rslvDisabled <- readIORef $ rslvDisabled s
+  pure NameResolverStatsData {_rslvReqs, _rslvSucc, _rslvNotFound, _rslvResolverErrs, _rslvDisabled}
+
+getResetNameResolverStatsData :: NameResolverStats -> IO NameResolverStatsData
+getResetNameResolverStatsData s = do
+  _rslvReqs <- atomicSwapIORef (rslvReqs s) 0
+  _rslvSucc <- atomicSwapIORef (rslvSucc s) 0
+  _rslvNotFound <- atomicSwapIORef (rslvNotFound s) 0
+  _rslvResolverErrs <- atomicSwapIORef (rslvResolverErrs s) 0
+  _rslvDisabled <- atomicSwapIORef (rslvDisabled s) 0
+  pure NameResolverStatsData {_rslvReqs, _rslvSucc, _rslvNotFound, _rslvResolverErrs, _rslvDisabled}
+
+-- not thread safe; used on server start only
+setNameResolverStats :: NameResolverStats -> NameResolverStatsData -> IO ()
+setNameResolverStats s d = do
+  writeIORef (rslvReqs s) $! _rslvReqs d
+  writeIORef (rslvSucc s) $! _rslvSucc d
+  writeIORef (rslvNotFound s) $! _rslvNotFound d
+  writeIORef (rslvResolverErrs s) $! _rslvResolverErrs d
+  writeIORef (rslvDisabled s) $! _rslvDisabled d
+
+instance StrEncoding NameResolverStatsData where
+  strEncode NameResolverStatsData {_rslvReqs, _rslvSucc, _rslvNotFound, _rslvResolverErrs, _rslvDisabled} =
+    "reqs="
+      <> strEncode _rslvReqs
+      <> "\nsucc="
+      <> strEncode _rslvSucc
+      <> "\nnotFound="
+      <> strEncode _rslvNotFound
+      <> "\nresolverErrs="
+      <> strEncode _rslvResolverErrs
+      <> "\ndisabled="
+      <> strEncode _rslvDisabled
+  strP = do
+    _rslvReqs <- "reqs=" *> strP <* A.endOfLine
+    _rslvSucc <- "succ=" *> strP <* A.endOfLine
+    _rslvNotFound <- "notFound=" *> strP <* A.endOfLine
+    _rslvResolverErrs <- "resolverErrs=" *> strP <* A.endOfLine
+    _rslvDisabled <- "disabled=" *> strP
+    pure NameResolverStatsData {_rslvReqs, _rslvSucc, _rslvNotFound, _rslvResolverErrs, _rslvDisabled}
+
 data ServiceStats = ServiceStats
   { srvAssocNew :: IORef Int,
     srvAssocDuplicate :: IORef Int,

src/Simplex/Messaging/Server/Web.hs

@@ -270,14 +270,14 @@ serverInfoSubsts simplexmqSource information =
       ]
     admin ServerContactAddress {simplex, email, pgp} =
       [ ("admin", Just ""),
-        ("adminSimplex", strEncode <$> simplex),
+        ("adminSimplex", encodeUtf8 <$> simplex),
         ("adminEmail", encodeUtf8 <$> email),
         ("adminPGP", encodeUtf8 . pkURI <$> pgp),
         ("adminPGPFingerprint", encodeUtf8 . pkFingerprint <$> pgp)
       ]
     complaints ServerContactAddress {simplex, email, pgp} =
       [ ("complaints", Just ""),
-        ("complaintsSimplex", strEncode <$> simplex),
+        ("complaintsSimplex", encodeUtf8 <$> simplex),
         ("complaintsEmail", encodeUtf8 <$> email),
         ("complaintsPGP", encodeUtf8 . pkURI <$> pgp),
         ("complaintsPGPFingerprint", encodeUtf8 . pkFingerprint <$> pgp)

src/Simplex/Messaging/ServiceScheme.hs

@@ -11,8 +11,9 @@ import Control.Applicative ((<|>))
 import qualified Data.Attoparsec.ByteString.Char8 as A
 import qualified Data.ByteString.Char8 as B
 import Data.Functor (($>))
-import Network.Socket (HostName, ServiceName)
+import Network.Socket (ServiceName)
 import Simplex.Messaging.Encoding.String (StrEncoding (..))
+import Simplex.Messaging.Transport.Client (TransportHost (..))
 
 data ServiceScheme = SSSimplex | SSAppServer SrvLoc
   deriving (Eq, Show)
@@ -25,14 +26,19 @@ instance StrEncoding ServiceScheme where
     "simplex:" $> SSSimplex
       <|> "https://" *> (SSAppServer <$> strP)
 
-data SrvLoc = SrvLoc HostName ServiceName
+data SrvLoc = SrvLoc TransportHost ServiceName
   deriving (Eq, Ord, Show)
 
 instance StrEncoding SrvLoc where
-  strEncode (SrvLoc host port) = B.pack $ host <> if null port then "" else ':' : port
-  strP = SrvLoc <$> host <*> (port <|> pure "")
+  strEncode (SrvLoc host port)
+    | null port = strEncode host
+    | otherwise = h <> B.pack (':' : port)
+    where
+      h = case host of
+        THIPv6 _ -> ('[' `B.cons` strEncode host) `B.snoc` ']'
+        _ -> strEncode host
+  strP = SrvLoc <$> strP <*> (port <|> pure "")
     where
-      host = B.unpack <$> A.takeWhile1 (A.notInClass ":#,;/ ")
       port = show <$> (A.char ':' *> (A.decimal :: A.Parser Int))
 
 simplexChat :: ServiceScheme

src/Simplex/Messaging/Session.hs

@@ -6,14 +6,20 @@ module Simplex.Messaging.Session
   ( SessionVar (..),
     getSessVar,
     removeSessVar,
+    withGetSessVar,
+    withGetSessVar',
     tryReadSessVar,
   ) where
 
 import Control.Concurrent.STM
+import Control.Monad.Except (ExceptT (..), runExceptT)
+import Control.Monad.IO.Class (liftIO)
+import Control.Monad.IO.Unlift (MonadUnliftIO)
 import Data.Time (UTCTime)
 import Simplex.Messaging.TMap (TMap)
 import qualified Simplex.Messaging.TMap as TM
-import Simplex.Messaging.Util (($>>=))
+import Simplex.Messaging.Util (whenM, ($>>=))
+import UnliftIO.Exception (bracketOnError)
 
 data SessionVar a = SessionVar
   { sessionVar :: TMVar a,
@@ -38,5 +44,31 @@ removeSessVar v sessKey vs =
     Just v' | sessionVarId v == sessionVarId v' -> TM.delete sessKey vs
     _ -> pure ()
 
+-- | Get or create a session var and route to onNew (newly created) or onExisting. The new-var
+-- branch is bracketed from the point of creation: if it is interrupted before filling the var
+-- (e.g. an async exception during connect), the still-empty var is dropped from the map so the
+-- next request creates a fresh session instead of blocking on a var that will never be filled.
+-- A thrown ExceptT error is a normal result (the var keeps the error it was filled with) - only
+-- an interrupting exception drops the empty var.
+withGetSessVar ::
+  (Ord k, MonadUnliftIO m) =>
+  TVar Int -> k -> TMap k (SessionVar a) -> UTCTime ->
+  (SessionVar a -> ExceptT e m b) -> (SessionVar a -> ExceptT e m b) -> ExceptT e m b
+withGetSessVar sessSeq sessKey vs ts onNew onExisting =
+  ExceptT $ withGetSessVar' sessSeq sessKey vs ts (runExceptT . onNew) (runExceptT . onExisting)
+
+-- | withGetSessVar for actions in the underlying monad (without ExceptT).
+withGetSessVar' ::
+  (Ord k, MonadUnliftIO m) =>
+  TVar Int -> k -> TMap k (SessionVar a) -> UTCTime ->
+  (SessionVar a -> m b) -> (SessionVar a -> m b) -> m b
+withGetSessVar' sessSeq sessKey vs ts onNew onExisting =
+  bracketOnError
+    (liftIO $ atomically $ getSessVar sessSeq sessKey vs ts)
+    (either (liftIO . atomically . dropEmptySessVar) (\_ -> pure ()))
+    (either onNew onExisting)
+  where
+    dropEmptySessVar v = whenM (isEmptyTMVar $ sessionVar v) $ removeSessVar v sessKey vs
+
 tryReadSessVar :: Ord k => k -> TMap k (SessionVar a) -> STM (Maybe a)
 tryReadSessVar sessKey vs = TM.lookup sessKey vs $>>= (tryReadTMVar . sessionVar)

src/Simplex/Messaging/SimplexName.hs

@@ -0,0 +1,137 @@
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE StrictData #-}
+{-# LANGUAGE TemplateHaskell #-}
+
+module Simplex.Messaging.SimplexName
+  ( SimplexNameInfo (..),
+    SimplexDomain (..),
+    SimplexTLD (..),
+    SimplexNameType (..),
+    fullDomainName,
+    shortNameInfoStr,
+  )
+where
+
+import Control.Applicative (optional, (<|>))
+import qualified Data.Aeson.TH as J
+import qualified Data.Attoparsec.ByteString.Char8 as A
+import qualified Data.Attoparsec.Text as AT
+import Data.ByteString.Char8 (ByteString)
+import qualified Data.ByteString.Char8 as B
+import Data.Char (isDigit)
+import Data.Functor (($>))
+import Data.Text (Text)
+import qualified Data.Text as T
+import Data.Text.Encoding (decodeLatin1, encodeUtf8)
+import Simplex.Messaging.Agent.Store.DB (FromField (..), ToField (..), fromTextField_)
+import Simplex.Messaging.Encoding (Encoding (..))
+import Simplex.Messaging.Encoding.String
+import Simplex.Messaging.Parsers (defaultJSON, dropPrefix, enumJSON)
+import Simplex.Messaging.Util (eitherToMaybe, safeDecodeUtf8, (<$?>))
+
+data SimplexNameInfo = SimplexNameInfo
+  { nameType :: SimplexNameType,
+    nameDomain :: SimplexDomain
+  }
+  deriving (Eq, Show)
+
+data SimplexDomain = SimplexDomain
+  { nameTLD :: SimplexTLD,
+    domain :: Text,
+    subDomain :: [Text] -- parent to child: ["b", "a"] for a.b.domain.simplex
+  }
+  deriving (Eq, Show)
+
+data SimplexTLD = TLDSimplex | TLDTesting | TLDWeb
+  deriving (Eq, Show)
+
+data SimplexNameType = NTPublicGroup | NTContact
+  deriving (Eq, Show)
+
+instance StrEncoding SimplexNameType where
+  strEncode = \case
+    NTPublicGroup -> "#"
+    NTContact -> "@"
+  strP = A.char '#' $> NTPublicGroup <|> A.char '@' $> NTContact
+
+nameLabelP :: AT.Parser Text
+nameLabelP = do
+  label <- T.intercalate "-" <$> AT.takeWhile1 (\c -> isNameLetter c || isDigit c) `AT.sepBy1` AT.char '-'
+  -- DNS label limit: each dot-separated component is at most 63 bytes (labels
+  -- are ASCII, so character count == byte count)
+  if T.length label > 63 then fail "name label exceeds 63 bytes" else pure label
+  where
+    -- ASCII letters only. SNRC contracts hash byte sequences via keccak; ENS
+    -- uses UTS-46 + Punycode for IDN, which we do not implement. Admitting
+    -- Cyrillic / Greek / etc. via Data.Char.isAlpha would (a) make namehash
+    -- diverge from any IDN-aware registrar and (b) allow homograph spoofing
+    -- (Cyrillic а vs ASCII a hash to different on-chain records).
+    isNameLetter c = c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z'
+
+-- | Cap the name at 253 bytes (DNS full-domain limit)
+boundedNonSpace :: A.Parser ByteString
+boundedNonSpace = do
+  bs <- A.scan (0 :: Int) $ \i c ->
+    if i <= 253 && not (A.isSpace c) then Just (i + 1) else Nothing
+  if B.null bs
+    then fail "expected non-empty name token"
+    else if B.length bs > 253 then fail "name exceeds 253 bytes" else pure bs
+
+instance StrEncoding SimplexNameInfo where
+  strEncode SimplexNameInfo {nameType, nameDomain} =
+    strEncode nameType <> strEncode nameDomain
+  strP = optional "simplex:/name" *> ((strP >>= infoP) <|> infoP NTPublicGroup)
+    where
+      infoP NTPublicGroup = SimplexNameInfo NTPublicGroup <$> (strP <|> bareName)
+      infoP NTContact = SimplexNameInfo NTContact <$> strP
+      bareName = parseBare . safeDecodeUtf8 <$?> boundedNonSpace
+      parseBare s = (\name -> SimplexDomain TLDSimplex (T.toLower name) []) <$> AT.parseOnly (nameLabelP <* AT.endOfInput) s
+
+instance StrEncoding SimplexDomain where
+  strEncode = encodeUtf8 . fullDomainName
+  strP = parseDomain . safeDecodeUtf8 <$?> boundedNonSpace
+    where
+      parseDomain s = AT.parseOnly (nameLabelP `AT.sepBy1` AT.char '.' <* AT.endOfInput) s >>= mkDomain
+      mkDomain labels = case reverse lowered of
+        [] -> Left "empty name"
+        [_] -> Left "domain requires TLD"
+        "simplex" : name : sub -> Right (SimplexDomain TLDSimplex name sub)
+        "testing" : name : sub -> Right (SimplexDomain TLDTesting name sub)
+        _ -> Right (SimplexDomain TLDWeb (T.intercalate "." lowered) [])
+        where
+          lowered = map T.toLower labels
+
+instance Encoding SimplexDomain where
+  smpEncode = strEncode
+  smpP = strP
+
+fullDomainName :: SimplexDomain -> Text
+fullDomainName SimplexDomain {nameTLD, domain, subDomain} = T.intercalate "." (reverse subDomain ++ [domain] ++ tld')
+  where
+    tld' = case nameTLD of
+      TLDSimplex -> ["simplex"]
+      TLDTesting -> ["testing"]
+      TLDWeb -> []
+
+shortNameInfoStr :: SimplexNameInfo -> Text
+shortNameInfoStr = \case
+  SimplexNameInfo {nameType = NTPublicGroup, nameDomain = SimplexDomain {nameTLD = TLDSimplex, domain, subDomain = []}} -> "#" <> domain
+  info -> pfx <> fullDomainName (nameDomain info)
+    where
+      pfx = case nameType info of
+        NTPublicGroup -> "#"
+        NTContact -> "@"
+
+instance ToField SimplexDomain where toField = toField . decodeLatin1 . strEncode
+
+instance FromField SimplexDomain where fromField = fromTextField_ (eitherToMaybe . strDecode . encodeUtf8)
+
+$(J.deriveJSON (enumJSON $ dropPrefix "TLD") ''SimplexTLD)
+
+$(J.deriveJSON (enumJSON $ dropPrefix "NT") ''SimplexNameType)
+
+$(J.deriveJSON defaultJSON ''SimplexDomain)
+
+$(J.deriveJSON defaultJSON ''SimplexNameInfo)

src/Simplex/Messaging/Transport.hs

@@ -46,17 +46,13 @@ module Simplex.Messaging.Transport
     minServerSMPRelayVersion,
     currentClientSMPRelayVersion,
     currentServerSMPRelayVersion,
-    authCmdsSMPVersion,
-    sendingProxySMPVersion,
-    sndAuthKeySMPVersion,
-    deletedEventSMPVersion,
-    encryptedBlockSMPVersion,
-    blockedEntitySMPVersion,
     shortLinksSMPVersion,
     serviceCertsSMPVersion,
     newNtfCredsSMPVersion,
     clientNoticesSMPVersion,
     rcvServiceSMPVersion,
+    namesSMPVersion,
+    serverInfoSMPVersion,
     simplexMQVersion,
     smpBlockSize,
     TransportConfig (..),
@@ -113,8 +109,8 @@ import Control.Monad
 import Control.Monad.Except
 import Control.Monad.IO.Class
 import Control.Monad.Trans.Except (throwE)
+import qualified Data.Aeson as J
 import qualified Data.Aeson.TH as J
-import Data.Attoparsec.ByteString.Char8 (Parser)
 import qualified Data.Attoparsec.ByteString.Char8 as A
 import Data.Bifunctor (first)
 import Data.Bitraversable (bimapM)
@@ -139,9 +135,10 @@ import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Parsers (dropPrefix, parseRead1, sumTypeJSON)
+import Simplex.Messaging.Server.Information
 import Simplex.Messaging.Transport.Buffer
 import Simplex.Messaging.Transport.Shared
-import Simplex.Messaging.Util (bshow, catchAll, catchAll_, liftEitherWith)
+import Simplex.Messaging.Util (bshow, catchAll, catchAll_, liftEitherWith, (<$$>))
 import Simplex.Messaging.Version
 import Simplex.Messaging.Version.Internal
 import System.IO.Error (isEOFError)
@@ -172,6 +169,8 @@ smpBlockSize = 16384
 -- 17 - create notification credentials with NEW (7/12/2025)
 -- 18 - support client notices (10/10/2025)
 -- 19 - service subscriptions to messages (10/20/2025)
+-- 20 - public namespaces resolver, RSLV command (6/20/2026)
+-- 21 - server public information in handshake (7/5/2026)
 
 data SMPVersion
 
@@ -184,29 +183,8 @@ type VersionRangeSMP = VersionRange SMPVersion
 pattern VersionSMP :: Word16 -> VersionSMP
 pattern VersionSMP v = Version v
 
-_subModeSMPVersion :: VersionSMP
-_subModeSMPVersion = VersionSMP 6
-
-authCmdsSMPVersion :: VersionSMP
-authCmdsSMPVersion = VersionSMP 7
-
-sendingProxySMPVersion :: VersionSMP
-sendingProxySMPVersion = VersionSMP 8
-
-sndAuthKeySMPVersion :: VersionSMP
-sndAuthKeySMPVersion = VersionSMP 9
-
-deletedEventSMPVersion :: VersionSMP
-deletedEventSMPVersion = VersionSMP 10
-
-encryptedBlockSMPVersion :: VersionSMP
-encryptedBlockSMPVersion = VersionSMP 11
-
-blockedEntitySMPVersion :: VersionSMP
-blockedEntitySMPVersion = VersionSMP 12
-
-proxyServerHandshakeSMPVersion :: VersionSMP
-proxyServerHandshakeSMPVersion = VersionSMP 14
+_proxyServerHandshakeSMPVersion :: VersionSMP
+_proxyServerHandshakeSMPVersion = VersionSMP 14
 
 shortLinksSMPVersion :: VersionSMP
 shortLinksSMPVersion = VersionSMP 15
@@ -223,37 +201,38 @@ clientNoticesSMPVersion = VersionSMP 18
 rcvServiceSMPVersion :: VersionSMP
 rcvServiceSMPVersion = VersionSMP 19
 
+namesSMPVersion :: VersionSMP
+namesSMPVersion = VersionSMP 20
+
+serverInfoSMPVersion :: VersionSMP
+serverInfoSMPVersion = VersionSMP 21
+
 minClientSMPRelayVersion :: VersionSMP
-minClientSMPRelayVersion = VersionSMP 6
+minClientSMPRelayVersion = VersionSMP 14
 
 minServerSMPRelayVersion :: VersionSMP
-minServerSMPRelayVersion = VersionSMP 6
+minServerSMPRelayVersion = VersionSMP 14
 
 currentClientSMPRelayVersion :: VersionSMP
-currentClientSMPRelayVersion = VersionSMP 19
-
-legacyServerSMPRelayVersion :: VersionSMP
-legacyServerSMPRelayVersion = VersionSMP 6
+currentClientSMPRelayVersion = VersionSMP 21
 
 currentServerSMPRelayVersion :: VersionSMP
-currentServerSMPRelayVersion = VersionSMP 19
+currentServerSMPRelayVersion = VersionSMP 21
 
--- Max SMP protocol version to be used in e2e encrypted
--- connection between client and server, as defined by SMP proxy.
--- SMP proxy sets it to lower than its current version
--- to prevent client version fingerprinting by the
--- destination relays when clients upgrade at different times.
+-- Max SMP protocol version to be used in e2e encrypted connection between
+-- client and server, as defined by SMP proxy. Normally set below the current
+-- version to prevent client version fingerprinting by the destination relays
+-- when clients upgrade at different times. Pinned to the current version (20)
+-- for this release because proxied name resolution is gated on namesSMPVersion
+-- (20), so the one-version anti-fingerprinting buffer does not apply yet; it
+-- reappears once the current version advances past 20.
 proxiedSMPRelayVersion :: VersionSMP
-proxiedSMPRelayVersion = VersionSMP 18
+proxiedSMPRelayVersion = VersionSMP 20
 
--- minimal supported protocol version is 6
--- TODO remove code that supports sending commands without batching
+-- minimal supported protocol version is 14
 supportedClientSMPRelayVRange :: VersionRangeSMP
 supportedClientSMPRelayVRange = mkVersionRange minClientSMPRelayVersion currentClientSMPRelayVersion
 
-legacyServerSMPRelayVRange :: VersionRangeSMP
-legacyServerSMPRelayVRange = mkVersionRange minServerSMPRelayVersion legacyServerSMPRelayVersion
-
 supportedServerSMPRelayVRange :: VersionRangeSMP
 supportedServerSMPRelayVRange = mkVersionRange minServerSMPRelayVersion currentServerSMPRelayVersion
 
@@ -261,7 +240,7 @@ supportedProxyClientSMPRelayVRange :: VersionRangeSMP
 supportedProxyClientSMPRelayVRange = mkVersionRange minServerSMPRelayVersion currentServerSMPRelayVersion
 
 proxiedSMPRelayVRange :: VersionRangeSMP
-proxiedSMPRelayVRange = mkVersionRange sendingProxySMPVersion proxiedSMPRelayVersion
+proxiedSMPRelayVRange = mkVersionRange minServerSMPRelayVersion proxiedSMPRelayVersion
 
 alpnSupportedSMPHandshakes :: [ALPN]
 alpnSupportedSMPHandshakes = ["smp/1"]
@@ -483,14 +462,14 @@ data THandleParams v p = THandleParams
     thAuth :: Maybe (THandleAuth p),
     -- | do NOT send session ID in transmission, but include it into signed message
     -- based on protocol version
+    -- This is True for SMP and NTF servers, and False for XFTP
     implySessId :: Bool,
     -- | keys for additional transport encryption
     encryptBlock :: Maybe TSbChainKeys,
-    -- | send multiple transmissions in a single block
-    -- based on protocol version
-    batch :: Bool,
     -- | include service signature (or '0' if it is absent), based on protocol version
-    serviceAuth :: Bool
+    serviceAuth :: Bool,
+    -- | JSON-encoded ServerPublicInfo from handshake, present when server version >= serverInfoSMPVersion
+    serverInfo :: Maybe (Either String ServerPublicInfo)
   }
 
 data THandleAuth (p :: TransportPeer) where
@@ -542,7 +521,9 @@ data SMPServerHandshake = SMPServerHandshake
     sessionId :: SessionId,
     -- pub key to agree shared secrets for command authorization and entity ID encryption.
     -- todo C.PublicKeyX25519
-    authPubKey :: Maybe CertChainPubKey
+    authPubKey :: CertChainPubKey,
+    -- | optional server public information (JSON-encoded ServerPublicInfo), sent when version >= serverInfoSMPVersion
+    serverInfoBytes :: Maybe ByteString
   }
 
 -- This is the third handshake message that SMP server sends to services
@@ -596,14 +577,13 @@ data SMPServiceRole = SRMessaging | SRNotifier | SRProxy deriving (Eq, Show)
 instance Encoding SMPClientHandshake where
   smpEncode SMPClientHandshake {smpVersion = v, keyHash, authPubKey, proxyServer, clientService} =
     smpEncode (v, keyHash)
-      <> encodeAuthEncryptCmds v authPubKey
-      <> ifHasProxy v (smpEncode proxyServer) ""
+      <> maybe "" smpEncode authPubKey
+      <> smpEncode proxyServer
       <> ifHasService v (smpEncode clientService) ""
   smpP = do
     (v, keyHash) <- smpP
-    -- TODO drop SMP v6: remove special parser and make key non-optional
-    authPubKey <- authEncryptCmdsP v smpP
-    proxyServer <- ifHasProxy v smpP (pure False)
+    authPubKey <- optional smpP
+    proxyServer <- smpP
     clientService <- ifHasService v smpP (pure Nothing)
     pure SMPClientHandshake {smpVersion = v, keyHash, authPubKey, proxyServer, clientService}
 
@@ -626,22 +606,21 @@ instance Encoding SMPServiceRole where
       'P' -> pure SRProxy
       _ -> fail "bad SMPServiceRole"
 
-ifHasProxy :: VersionSMP -> a -> a -> a
-ifHasProxy v a b = if v >= proxyServerHandshakeSMPVersion then a else b
-
 ifHasService :: VersionSMP -> a -> a -> a
 ifHasService v a b = if v >= serviceCertsSMPVersion then a else b
 
+ifHasServerInfo :: VersionSMP -> a -> a -> a
+ifHasServerInfo v a b = if v >= serverInfoSMPVersion then a else b
+
 instance Encoding SMPServerHandshake where
-  smpEncode SMPServerHandshake {smpVersionRange, sessionId, authPubKey} =
-    smpEncode (smpVersionRange, sessionId) <> auth
+  smpEncode SMPServerHandshake {smpVersionRange, sessionId, authPubKey, serverInfoBytes} =
+    smpEncode (smpVersionRange, sessionId, authPubKey) <> info
     where
-      auth = encodeAuthEncryptCmds (maxVersion smpVersionRange) authPubKey
+      info = ifHasServerInfo (maxVersion smpVersionRange) (smpEncode (Large <$> serverInfoBytes)) ""
   smpP = do
-    (smpVersionRange, sessionId) <- smpP
-    -- TODO drop SMP v6: remove special parser and make key non-optional
-    authPubKey <- authEncryptCmdsP (maxVersion smpVersionRange) smpP
-    pure SMPServerHandshake {smpVersionRange, sessionId, authPubKey}
+    (smpVersionRange, sessionId, authPubKey) <- smpP
+    serverInfoBytes <- ifHasServerInfo (maxVersion smpVersionRange) (unLarge <$$> smpP) (pure Nothing)
+    pure SMPServerHandshake {smpVersionRange, sessionId, authPubKey, serverInfoBytes}
 
 -- newtype for CertificateChain and a session key signed with this certificate
 data CertChainPubKey = CertChainPubKey
@@ -657,14 +636,6 @@ instance Encoding CertChainPubKey where
     C.SignedObject signedPubKey <- smpP
     pure CertChainPubKey {certChain, signedPubKey}
 
-encodeAuthEncryptCmds :: Encoding a => VersionSMP -> Maybe a -> ByteString
-encodeAuthEncryptCmds v k
-  | v >= authCmdsSMPVersion = maybe "" smpEncode k
-  | otherwise = ""
-
-authEncryptCmdsP :: VersionSMP -> Parser a -> Parser (Maybe a)
-authEncryptCmdsP v p = if v >= authCmdsSMPVersion then optional p else pure Nothing
-
 instance Encoding SMPServerHandshakeResponse where
   smpEncode = \case
     SMPServerHandshakeResponse serviceId -> smpEncode ('R', serviceId)
@@ -757,12 +728,12 @@ smpServerHandshake ::
   C.KeyPairX25519 ->
   C.KeyHash ->
   VersionRangeSMP ->
+  Maybe ByteString ->
   (SMPServiceRole -> X.CertificateChain -> XV.Fingerprint -> ExceptT TransportError IO ServiceId) ->
   ExceptT TransportError IO (THandleSMP c 'TServer)
-smpServerHandshake srvCert srvSignKey c (k, pk) kh smpVRange getService = do
+smpServerHandshake srvCert srvSignKey c (k, pk) kh smpVersionRange serverInfoBytes getService = do
   let sk = C.signX509 srvSignKey $ C.publicToX509 k
-      smpVersionRange = maybe legacyServerSMPRelayVRange (const smpVRange) $ getSessionALPN c
-  sendHandshake th $ SMPServerHandshake {sessionId, smpVersionRange, authPubKey = Just (CertChainPubKey srvCert sk)}
+  sendHandshake th $ SMPServerHandshake {sessionId, smpVersionRange, authPubKey = CertChainPubKey srvCert sk, serverInfoBytes}
   SMPClientHandshake {smpVersion = v, keyHash, authPubKey = k', proxyServer, clientService} <- getHandshake th
   when (keyHash /= kh) $ throwE $ TEHandshake IDENTITY
   case compatibleVRange' smpVersionRange v of
@@ -794,53 +765,34 @@ smpServerHandshake srvCert srvSignKey c (k, pk) kh smpVRange getService = do
 --
 -- See https://github.com/simplex-chat/simplexmq/blob/master/protocol/simplex-messaging.md#appendix-a
 smpClientHandshake :: forall c. Transport c => c 'TClient -> Maybe C.KeyPairX25519 -> C.KeyHash -> VersionRangeSMP -> Bool -> Maybe (ServiceCredentials, C.KeyPairEd25519) -> ExceptT TransportError IO (THandleSMP c 'TClient)
-smpClientHandshake c ks_ keyHash@(C.KeyHash kh) vRange proxyServer serviceKeys_ = do
-  SMPServerHandshake {sessionId = sessId, smpVersionRange, authPubKey} <- getHandshake th
+smpClientHandshake c ks_ keyHash@(C.KeyHash kh) smpVRange proxyServer serviceKeys_ = do
+  SMPServerHandshake {sessionId = sessId, smpVersionRange, authPubKey = certKey@(CertChainPubKey chain exact), serverInfoBytes} <- getHandshake th
   when (sessionId /= sessId) $ throwE TEBadSession
-  -- Below logic downgrades version range in case the "client" is SMP proxy server and it is
-  -- connected to the destination server of the version 11 or older.
-  -- It disables transport encryption between SMP proxy and destination relay.
-  --
-  -- Prior to version v6.3 the version between proxy and destination was capped at 8,
-  -- by mistake, which also disables transport encryption and the latest features.
-  --
-  -- Transport encryption between proxy and destination breaks clients with version 10 or earlier,
-  -- because of a larger message size (see maxMessageLength).
-  --
-  -- To summarize:
-  -- - proxy and relay version 12: the agreed version is 12, transport encryption disabled (see blockEncryption with proxyServer == True).
-  -- - proxy is v 12, relay is 11: the agreed version is 10, because of this logic, transport encryption is disabled.
-  let smpVRange =
-        if proxyServer && maxVersion smpVersionRange < proxyServerHandshakeSMPVersion
-          then vRange {maxVersion = max (minVersion vRange) deletedEventSMPVersion}
-          else vRange
   case smpVersionRange `compatibleVRange` smpVRange of
     Just (Compatible vr) -> do
-      ck_ <- forM authPubKey $ \certKey@(CertChainPubKey chain exact) ->
-        liftEitherWith (const $ TEHandshake BAD_AUTH) $ do
-          case chainIdCaCerts chain of
-            CCValid {idCert} | XV.Fingerprint kh == XV.getFingerprint idCert X.HashSHA256 -> pure ()
-            _ -> throwError "bad certificate"
-          serverKey <- getServerVerifyKey c
-          (,certKey) <$> (C.x509ToPublic' =<< C.verifyX509 serverKey exact)
+      ck <- liftEitherWith (const $ TEHandshake BAD_AUTH) $ do
+        case chainIdCaCerts chain of
+          CCValid {idCert} | XV.Fingerprint kh == XV.getFingerprint idCert X.HashSHA256 -> pure ()
+          _ -> throwError "bad certificate"
+        serverKey <- getServerVerifyKey c
+        (,certKey) <$> (C.x509ToPublic' =<< C.verifyX509 serverKey exact)
       let v = maxVersion vr
+          serviceVersion ServiceCredentials {serviceRole} = if serviceRole == SRMessaging then rcvServiceSMPVersion else serviceCertsSMPVersion
           serviceKeys = case serviceKeys_ of
-            Just sks | v >= serviceCertsSMPVersion && certificateSent c -> Just sks
+            Just sks | v >= serviceVersion (fst sks) && certificateSent c -> Just sks
             _ -> Nothing
-          clientService = mkClientService v =<< serviceKeys
+          clientService = mkClientService <$> serviceKeys
           hs = SMPClientHandshake {smpVersion = v, keyHash, authPubKey = fst <$> ks_, proxyServer, clientService}
       sendHandshake th hs
       service <- mapM getClientService serviceKeys
-      liftIO $ smpTHandleClient th v vr (snd <$> ks_) ck_ proxyServer service
+      liftIO $ smpTHandleClient th v vr (snd <$> ks_) ck proxyServer service serverInfoBytes
     Nothing -> throwE TEVersion
   where
     th@THandle {params = THandleParams {sessionId}} = smpTHandle c
-    mkClientService :: VersionSMP -> (ServiceCredentials, C.KeyPairEd25519) -> Maybe SMPClientHandshakeService
-    mkClientService v (ServiceCredentials {serviceRole, serviceCreds, serviceSignKey}, (k, _))
-      | serviceRole == SRMessaging && v < rcvServiceSMPVersion = Nothing
-      | otherwise =
-          let sk = C.signX509 serviceSignKey $ C.publicToX509 k
-           in Just SMPClientHandshakeService {serviceRole, serviceCertKey = CertChainPubKey (fst serviceCreds) sk}
+    mkClientService :: (ServiceCredentials, C.KeyPairEd25519) -> SMPClientHandshakeService
+    mkClientService (ServiceCredentials {serviceRole, serviceCreds, serviceSignKey}, (k, _)) =
+      let sk = C.signX509 serviceSignKey $ C.publicToX509 k
+       in SMPClientHandshakeService {serviceRole, serviceCertKey = CertChainPubKey (fst serviceCreds) sk}
     getClientService :: (ServiceCredentials, C.KeyPairEd25519) -> ExceptT TransportError IO THClientService
     getClientService (ServiceCredentials {serviceRole, serviceCertHash}, (_, pk)) =
       getHandshake th >>= \case
@@ -850,17 +802,17 @@ smpClientHandshake c ks_ keyHash@(C.KeyHash kh) vRange proxyServer serviceKeys_
 smpTHandleServer :: forall c. THandleSMP c 'TServer -> VersionSMP -> VersionRangeSMP -> C.PrivateKeyX25519 -> Maybe C.PublicKeyX25519 -> Bool -> Maybe THPeerClientService -> IO (THandleSMP c 'TServer)
 smpTHandleServer th v vr pk k_ proxyServer peerClientService = do
   let thAuth = Just THAuthServer {serverPrivKey = pk, peerClientService, sessSecret' = (`C.dh'` pk) <$!> k_}
-  be <- blockEncryption th v proxyServer thAuth
-  pure $ smpTHandle_ th v vr thAuth $ uncurry TSbChainKeys <$> be
+  be <- blockEncryption th proxyServer thAuth
+  pure $ smpTHandle_ th v vr thAuth (uncurry TSbChainKeys <$> be) Nothing
 
-smpTHandleClient :: forall c. THandleSMP c 'TClient -> VersionSMP -> VersionRangeSMP -> Maybe C.PrivateKeyX25519 -> Maybe (C.PublicKeyX25519, CertChainPubKey) -> Bool -> Maybe THClientService -> IO (THandleSMP c 'TClient)
-smpTHandleClient th v vr pk_ ck_ proxyServer clientService = do
-  let thAuth = clientTHParams <$!> ck_
-  be <- blockEncryption th v proxyServer thAuth
+smpTHandleClient :: forall c. THandleSMP c 'TClient -> VersionSMP -> VersionRangeSMP -> Maybe C.PrivateKeyX25519 -> (C.PublicKeyX25519, CertChainPubKey) -> Bool -> Maybe THClientService -> Maybe ByteString -> IO (THandleSMP c 'TClient)
+smpTHandleClient th v vr pk_ (k, ck) proxyServer clientService serverInfoBytes = do
+  let thAuth = Just $! clientTHParams
+  be <- blockEncryption th proxyServer thAuth
   -- swap is needed to use client's sndKey as server's rcvKey and vice versa
-  pure $ smpTHandle_ th v vr thAuth $ uncurry TSbChainKeys . swap <$> be
+  pure $ smpTHandle_ th v vr thAuth (uncurry TSbChainKeys . swap <$> be) serverInfoBytes
   where
-    clientTHParams (k, ck) =
+    clientTHParams =
       THAuthClient
         { peerServerPubKey = k,
           peerServerCertKey = forceCertChain ck,
@@ -868,9 +820,9 @@ smpTHandleClient th v vr pk_ ck_ proxyServer clientService = do
           sessSecret = C.dh' k <$!> pk_
         }
 
-blockEncryption :: THandleSMP c p -> VersionSMP -> Bool -> Maybe (THandleAuth p) -> IO (Maybe (TVar C.SbChainKey, TVar C.SbChainKey))
-blockEncryption THandle {params = THandleParams {sessionId}} v proxyServer = \case
-  Just thAuth | not proxyServer && v >= encryptedBlockSMPVersion -> case thAuth of
+blockEncryption :: THandleSMP c p -> Bool -> Maybe (THandleAuth p) -> IO (Maybe (TVar C.SbChainKey, TVar C.SbChainKey))
+blockEncryption THandle {params = THandleParams {sessionId}} proxyServer = \case
+  Just thAuth | not proxyServer -> case thAuth of
     THAuthClient {sessSecret} -> be sessSecret
     THAuthServer {sessSecret'} -> be sessSecret'
   _ -> pure Nothing
@@ -878,8 +830,8 @@ blockEncryption THandle {params = THandleParams {sessionId}} v proxyServer = \ca
     be :: Maybe C.DhSecretX25519 -> IO (Maybe (TVar C.SbChainKey, TVar C.SbChainKey))
     be = mapM $ \(C.DhSecretX25519 secret) -> bimapM newTVarIO newTVarIO $ C.sbcInit sessionId secret
 
-smpTHandle_ :: forall c p. THandleSMP c p -> VersionSMP -> VersionRangeSMP -> Maybe (THandleAuth p) -> Maybe TSbChainKeys -> THandleSMP c p
-smpTHandle_ th@THandle {params} v vr thAuth encryptBlock =
+smpTHandle_ :: forall c p. THandleSMP c p -> VersionSMP -> VersionRangeSMP -> Maybe (THandleAuth p) -> Maybe TSbChainKeys -> Maybe ByteString -> THandleSMP c p
+smpTHandle_ th@THandle {params} v vr thAuth encryptBlock serverInfoBytes =
   -- TODO drop SMP v6: make thAuth non-optional
   -- * Note: update version-based parameters in smpTHParamsSetVersion as well.
   let params' =
@@ -887,9 +839,9 @@ smpTHandle_ th@THandle {params} v vr thAuth encryptBlock =
           { thVersion = v,
             thServerVRange = vr,
             thAuth,
-            implySessId = v >= authCmdsSMPVersion,
             encryptBlock,
-            serviceAuth = v >= serviceCertsSMPVersion -- optional service signature will be encoded for all commands and responses
+            serviceAuth = v >= serviceCertsSMPVersion, -- optional service signature will be encoded for all commands and responses
+            serverInfo = J.eitherDecodeStrict' <$> serverInfoBytes
           }
    in (th :: THandleSMP c p) {params = params'}
 
@@ -925,10 +877,10 @@ smpTHandle c = THandle {connection = c, params}
           thServerVRange = versionToRange v,
           thVersion = v,
           thAuth = Nothing,
-          implySessId = False,
+          implySessId = True,
           encryptBlock = Nothing,
-          batch = True,
-          serviceAuth = False
+          serviceAuth = False,
+          serverInfo = Nothing
         }
 
 $(J.deriveJSON (sumTypeJSON id) ''HandshakeError)

src/Simplex/Messaging/Transport/Client.hs

@@ -89,7 +89,7 @@ instance StrEncoding TransportHost where
       [ THIPv4 <$> ((,,,) <$> ipNum <*> ipNum <*> ipNum <*> A.decimal),
         maybe (Left "bad IPv6") (Right . THIPv6 . fromIPv6w) . readMaybe . B.unpack <$?> ipv6StrP,
         THOnionHost <$> ((<>) <$> A.takeWhile (\c -> isAsciiLower c || isDigit c) <*> A.string ".onion"),
-        THDomainName . B.unpack <$> (notOnion <$?> A.takeWhile1 (A.notInClass ":#,;/ \n\r\t"))
+        THDomainName . B.unpack <$> (notOnion <$?> A.takeWhile1 (A.notInClass ":#,;/ \n\r\t[]"))
       ]
     where
       ipNum = validIP <$?> (A.decimal <* A.char '.')

src/Simplex/RemoteControl/Invitation.hs

@@ -81,7 +81,7 @@ instance StrEncoding RCInvitation where
     _ <- A.string "xrcp:/"
     ca <- strP
     _ <- A.char '@'
-    host <- A.takeWhile (/= ':') >>= either fail pure . strDecode . urlDecode True
+    host <- strP
     _ <- A.char ':'
     port <- strP
     _ <- A.string "#/?"

tests/AgentTests.hs

@@ -12,6 +12,7 @@ import AgentTests.ConnectionRequestTests
 import AgentTests.DoubleRatchetTests (doubleRatchetTests)
 import AgentTests.FunctionalAPITests (functionalAPITests)
 import AgentTests.MigrationTests (migrationTests)
+import AgentTests.ResolveNameTests (resolveNameTests)
 import AgentTests.ServerChoice (serverChoiceTests)
 import AgentTests.ShortLinkTests (shortLinkTests)
 import Simplex.Messaging.Server.Env.STM (AStoreType (..))
@@ -37,6 +38,7 @@ agentCoreTests = do
   describe "Connection request" connectionRequestTests
   describe "Double ratchet tests" doubleRatchetTests
   describe "Short link tests" shortLinkTests
+  describe "resolve names" resolveNameTests
 
 agentTests :: (ASrvTransport, AStoreType) -> Spec
 agentTests ps = do

tests/AgentTests/ConnectionRequestTests.hs

@@ -18,6 +18,7 @@ module AgentTests.ConnectionRequestTests
     invConnRequest,
   ) where
 
+import AgentTests.EqInstances ()
 import Data.ByteString (ByteString)
 import Network.HTTP.Types (urlEncode)
 import Simplex.Messaging.Agent.Protocol
@@ -145,8 +146,8 @@ connReqData1 = connReqData {crSmpQueues = [queue1]}
 connReqDataV1 :: ConnReqUriData
 connReqDataV1 = connReqData {crAgentVRange = mkVersionRange (VersionSMPA 1) (VersionSMPA 1)}
 
-connReqDataV2 :: ConnReqUriData
-connReqDataV2 = connReqData {crAgentVRange = mkVersionRange (VersionSMPA 2) (VersionSMPA 2)}
+connReqDataV6 :: ConnReqUriData
+connReqDataV6 = connReqData {crAgentVRange = mkVersionRange (VersionSMPA 6) (VersionSMPA 6)}
 
 connReqDataNew :: ConnReqUriData
 connReqDataNew = connReqData {crSmpQueues = [queueNew]}
@@ -158,10 +159,10 @@ testDhPubKey :: C.PublicKeyX448
 testDhPubKey = "MEIwBQYDK2VvAzkAmKuSYeQ/m0SixPDS8Wq8VBaTS1cW+Lp0n0h4Diu+kUpR+qXx4SDJ32YGEFoGFGSbGPry5Ychr6U="
 
 testE2ERatchetParams :: RcvE2ERatchetParamsUri 'C.X448
-testE2ERatchetParams = E2ERatchetParamsUri (mkVersionRange (VersionE2E 1) (VersionE2E 1)) testDhPubKey testDhPubKey Nothing
+testE2ERatchetParams = E2ERatchetParamsUri (mkVersionRange (VersionE2E 3) (VersionE2E 3)) testDhPubKey testDhPubKey Nothing
 
 testE2ERatchetParamsStrUri :: ByteString
-testE2ERatchetParamsStrUri = "v%3D1%26x3dh%3DMEIwBQYDK2VvAzkAmKuSYeQ_m0SixPDS8Wq8VBaTS1cW-Lp0n0h4Diu-kUpR-qXx4SDJ32YGEFoGFGSbGPry5Ychr6U%3D%2CMEIwBQYDK2VvAzkAmKuSYeQ_m0SixPDS8Wq8VBaTS1cW-Lp0n0h4Diu-kUpR-qXx4SDJ32YGEFoGFGSbGPry5Ychr6U%3D"
+testE2ERatchetParamsStrUri = "v%3D3%26x3dh%3DMEIwBQYDK2VvAzkAmKuSYeQ_m0SixPDS8Wq8VBaTS1cW-Lp0n0h4Diu-kUpR-qXx4SDJ32YGEFoGFGSbGPry5Ychr6U%3D%2CMEIwBQYDK2VvAzkAmKuSYeQ_m0SixPDS8Wq8VBaTS1cW-Lp0n0h4Diu-kUpR-qXx4SDJ32YGEFoGFGSbGPry5Ychr6U%3D"
 
 testE2ERatchetParams12 :: RcvE2ERatchetParamsUri 'C.X448
 testE2ERatchetParams12 = E2ERatchetParamsUri supportedE2EEncryptVRange testDhPubKey testDhPubKey Nothing
@@ -176,7 +177,7 @@ connectionRequestNoQM :: AConnectionRequestUri
 connectionRequestNoQM = ACR SCMInvitation $ CRInvitationUri connReqDataNoQM testE2ERatchetParams
 
 connectionRequestContact :: AConnectionRequestUri
-connectionRequestContact = ACR SCMContact $ CRContactUri connReqDataContact
+connectionRequestContact = ACR SCMContact $ CRContactUri connReqDataContact Nothing
 
 connectionRequestV1 :: AConnectionRequestUri
 connectionRequestV1 = ACR SCMInvitation $ CRInvitationUri connReqDataV1 testE2ERatchetParams
@@ -194,13 +195,16 @@ contactAddress :: AConnectionRequestUri
 contactAddress = ACR SCMContact $ contactConnRequest
 
 contactConnRequest :: ConnectionRequestUri 'CMContact
-contactConnRequest = CRContactUri connReqData
+contactConnRequest = CRContactUri connReqData Nothing
 
-contactAddressV2 :: AConnectionRequestUri
-contactAddressV2 = ACR SCMContact $ CRContactUri connReqDataV2
+contactAddressDR :: AConnectionRequestUri
+contactAddressDR = ACR SCMContact $ CRContactUri connReqData (Just (RatchetKeyId "0123456789abcdef", testE2ERatchetParams))
+
+contactAddressV6 :: AConnectionRequestUri
+contactAddressV6 = ACR SCMContact $ CRContactUri connReqDataV6 Nothing
 
 contactAddressNew :: AConnectionRequestUri
-contactAddressNew = ACR SCMContact $ CRContactUri connReqDataNew
+contactAddressNew = ACR SCMContact $ CRContactUri connReqDataNew Nothing
 
 connectionRequest2queues :: AConnectionRequestUri
 connectionRequest2queues = ACR SCMInvitation $ CRInvitationUri connReqData {crSmpQueues = [queue, queue]} testE2ERatchetParams
@@ -209,16 +213,20 @@ connectionRequest2queuesNew :: AConnectionRequestUri
 connectionRequest2queuesNew = ACR SCMInvitation $ CRInvitationUri connReqDataNew {crSmpQueues = [queueNew, queueNew]} testE2ERatchetParams
 
 contactAddress2queues :: AConnectionRequestUri
-contactAddress2queues = ACR SCMContact $ CRContactUri connReqData {crSmpQueues = [queue, queue]}
+contactAddress2queues = ACR SCMContact $ CRContactUri connReqData {crSmpQueues = [queue, queue]} Nothing
 
 contactAddress2queuesNew :: AConnectionRequestUri
-contactAddress2queuesNew = ACR SCMContact $ CRContactUri connReqDataNew {crSmpQueues = [queueNew, queueNew]}
+contactAddress2queuesNew = ACR SCMContact $ CRContactUri connReqDataNew {crSmpQueues = [queueNew, queueNew]} Nothing
 
 connectionRequestClientDataEmpty :: AConnectionRequestUri
 connectionRequestClientDataEmpty = ACR SCMInvitation $ CRInvitationUri connReqData {crClientData = Just "{}"} testE2ERatchetParams
 
 contactAddressClientData :: AConnectionRequestUri
-contactAddressClientData = ACR SCMContact $ CRContactUri connReqData {crClientData = Just "{\"type\":\"group_link\", \"group_link_id\":\"abc\"}"}
+contactAddressClientData = ACR SCMContact $ CRContactUri connReqData {crClientData = Just "{\"type\":\"group_link\", \"group_link_id\":\"abc\"}"} Nothing
+
+-- binary encoding is defined only for BinaryConnectionRequestUri; drop the address keys for the round-trip
+aBinaryConnReq :: AConnectionRequestUri -> ABinaryConnectionRequestUri
+aBinaryConnReq (ACR m cr) = ABCR m (binaryConnReq cr)
 
 url :: ByteString -> ByteString
 url = urlEncode True
@@ -256,26 +264,27 @@ connectionRequestTests =
       queueV1NoPort #== ("smp://1234-w==@smp.simplex.im/3456-w==#/?v=1-1&dh=" <> url testDhKeyStr <> "&srv=jjbyvoemxysm7qxap7m5d5m35jzv5qq6gnlv7s4rsn7tdwwmuqciwpid.onion")
       queueV1NoPort #== ("smp://1234-w==@smp.simplex.im,jjbyvoemxysm7qxap7m5d5m35jzv5qq6gnlv7s4rsn7tdwwmuqciwpid.onion/3456-w==#" <> testDhKeyStr)
     it "should serialize and parse connection invitations and contact addresses" $ do
-      connectionRequest #==# ("simplex:/invitation#/?v=2-7&smp=" <> url queueStr <> "&e2e=" <> testE2ERatchetParamsStrUri)
-      connectionRequest #== ("https://simplex.chat/invitation#/?v=2-7&smp=" <> url queueStr <> "&e2e=" <> testE2ERatchetParamsStrUri)
-      connectionRequestNoQM #==# ("simplex:/invitation#/?v=2-7&smp=" <> url queueStrNoQM <> "&e2e=" <> testE2ERatchetParamsStrUri)
-      connectionRequest1 #==# ("simplex:/invitation#/?v=2-7&smp=" <> url queue1Str <> "&e2e=" <> testE2ERatchetParamsStrUri)
-      connectionRequest2queues #==# ("simplex:/invitation#/?v=2-7&smp=" <> url (queueStr <> ";" <> queueStr) <> "&e2e=" <> testE2ERatchetParamsStrUri)
-      connectionRequestNew #==# ("simplex:/invitation#/?v=2-7&smp=" <> url queueNewStr <> "&e2e=" <> testE2ERatchetParamsStrUri)
-      connectionRequestNew1 #==# ("simplex:/invitation#/?v=2-7&smp=" <> url queueNew1Str <> "&e2e=" <> testE2ERatchetParamsStrUri)
-      connectionRequest2queuesNew #==# ("simplex:/invitation#/?v=2-7&smp=" <> url (queueNewStr <> ";" <> queueNewStr) <> "&e2e=" <> testE2ERatchetParamsStrUri)
+      connectionRequest #==# ("simplex:/invitation#/?v=6-8&smp=" <> url queueStr <> "&e2e=" <> testE2ERatchetParamsStrUri)
+      connectionRequest #== ("https://simplex.chat/invitation#/?v=6-8&smp=" <> url queueStr <> "&e2e=" <> testE2ERatchetParamsStrUri)
+      connectionRequestNoQM #==# ("simplex:/invitation#/?v=6-8&smp=" <> url queueStrNoQM <> "&e2e=" <> testE2ERatchetParamsStrUri)
+      connectionRequest1 #==# ("simplex:/invitation#/?v=6-8&smp=" <> url queue1Str <> "&e2e=" <> testE2ERatchetParamsStrUri)
+      connectionRequest2queues #==# ("simplex:/invitation#/?v=6-8&smp=" <> url (queueStr <> ";" <> queueStr) <> "&e2e=" <> testE2ERatchetParamsStrUri)
+      connectionRequestNew #==# ("simplex:/invitation#/?v=6-8&smp=" <> url queueNewStr <> "&e2e=" <> testE2ERatchetParamsStrUri)
+      connectionRequestNew1 #==# ("simplex:/invitation#/?v=6-8&smp=" <> url queueNew1Str <> "&e2e=" <> testE2ERatchetParamsStrUri)
+      connectionRequest2queuesNew #==# ("simplex:/invitation#/?v=6-8&smp=" <> url (queueNewStr <> ";" <> queueNewStr) <> "&e2e=" <> testE2ERatchetParamsStrUri)
       connectionRequestV1 #== ("https://simplex.chat/invitation#/?v=1&smp=" <> url queueStr <> "&e2e=" <> testE2ERatchetParamsStrUri)
-      connectionRequestClientDataEmpty #==# ("simplex:/invitation#/?v=2-7&smp=" <> url queueStr <> "&e2e=" <> testE2ERatchetParamsStrUri <> "&data=" <> url "{}")
-      contactAddress #==# ("simplex:/contact#/?v=2-7&smp=" <> url queueStr)
-      contactAddress #== ("https://simplex.chat/contact#/?v=2-7&smp=" <> url queueStr)
-      contactAddress2queues #==# ("simplex:/contact#/?v=2-7&smp=" <> url (queueStr <> ";" <> queueStr))
-      contactAddressNew #==# ("simplex:/contact#/?v=2-7&smp=" <> url queueNewStr)
-      contactAddress2queuesNew #==# ("simplex:/contact#/?v=2-7&smp=" <> url (queueNewStr <> ";" <> queueNewStr))
-      contactAddressV2 #==# ("simplex:/contact#/?v=2&smp=" <> url queueStr)
-      contactAddressV2 #== ("https://simplex.chat/contact#/?v=1&smp=" <> url queueStr) -- adjusted to v2
-      contactAddressV2 #== ("https://simplex.chat/contact#/?v=1-2&smp=" <> url queueStr) -- adjusted to v2
-      contactAddressV2 #== ("https://simplex.chat/contact#/?v=2-2&smp=" <> url queueStr)
-      contactAddressClientData #==# ("simplex:/contact#/?v=2-7&smp=" <> url queueStr <> "&data=" <> url "{\"type\":\"group_link\", \"group_link_id\":\"abc\"}")
+      connectionRequestClientDataEmpty #==# ("simplex:/invitation#/?v=6-8&smp=" <> url queueStr <> "&e2e=" <> testE2ERatchetParamsStrUri <> "&data=" <> url "{}")
+      contactAddress #==# ("simplex:/contact#/?v=6-8&smp=" <> url queueStr)
+      contactAddressDR #==# ("simplex:/contact#/?v=6-8&smp=" <> url queueStr <> "&e2e=" <> testE2ERatchetParamsStrUri <> "&rk=MDEyMzQ1Njc4OWFiY2RlZg%3D%3D")
+      contactAddress #== ("https://simplex.chat/contact#/?v=6-8&smp=" <> url queueStr)
+      contactAddress2queues #==# ("simplex:/contact#/?v=6-8&smp=" <> url (queueStr <> ";" <> queueStr))
+      contactAddressNew #==# ("simplex:/contact#/?v=6-8&smp=" <> url queueNewStr)
+      contactAddress2queuesNew #==# ("simplex:/contact#/?v=6-8&smp=" <> url (queueNewStr <> ";" <> queueNewStr))
+      contactAddressV6 #==# ("simplex:/contact#/?v=6&smp=" <> url queueStr)
+      contactAddressV6 #== ("https://simplex.chat/contact#/?v=1&smp=" <> url queueStr) -- adjusted to v6
+      contactAddressV6 #== ("https://simplex.chat/contact#/?v=1-2&smp=" <> url queueStr) -- adjusted to v6
+      contactAddressV6 #== ("https://simplex.chat/contact#/?v=2-2&smp=" <> url queueStr)
+      contactAddressClientData #==# ("simplex:/contact#/?v=6-8&smp=" <> url queueStr <> "&data=" <> url "{\"type\":\"group_link\", \"group_link_id\":\"abc\"}")
     it "should serialize / parse queue address, connection invitations and contact addresses as binary" $ do
       smpEncodingTest queue
       smpEncodingTest queueNoQM -- this passes, no queue mode patch in SMPQueueUri encoding
@@ -287,21 +296,21 @@ connectionRequestTests =
       smpEncodingTest queueNew1NoPort
       smpEncodingTest queueV1
       smpEncodingTest queueV1NoPort
-      smpEncodingTest connectionRequest
+      smpEncodingTest (aBinaryConnReq connectionRequest)
       -- smpEncodingTest connectionRequestNoQM -- this fails, because of queue mode patch
-      smpEncodingTest connectionRequestContact -- this passes because of queue mode patch in ConnReqUriData encoding
-      smpEncodingTest connectionRequest1
-      smpEncodingTest connectionRequest2queues
-      smpEncodingTest connectionRequestNew
-      smpEncodingTest connectionRequestNew1
-      smpEncodingTest connectionRequest2queuesNew
-      smpEncodingTest connectionRequestClientDataEmpty
-      smpEncodingTest contactAddress
-      smpEncodingTest contactAddress2queues
-      smpEncodingTest contactAddressNew
-      smpEncodingTest contactAddress2queuesNew
-      smpEncodingTest contactAddressV2
-      smpEncodingTest contactAddressClientData
+      smpEncodingTest (aBinaryConnReq connectionRequestContact) -- this passes because of queue mode patch in ConnReqUriData encoding
+      smpEncodingTest (aBinaryConnReq connectionRequest1)
+      smpEncodingTest (aBinaryConnReq connectionRequest2queues)
+      smpEncodingTest (aBinaryConnReq connectionRequestNew)
+      smpEncodingTest (aBinaryConnReq connectionRequestNew1)
+      smpEncodingTest (aBinaryConnReq connectionRequest2queuesNew)
+      smpEncodingTest (aBinaryConnReq connectionRequestClientDataEmpty)
+      smpEncodingTest (aBinaryConnReq contactAddress)
+      smpEncodingTest (aBinaryConnReq contactAddress2queues)
+      smpEncodingTest (aBinaryConnReq contactAddressNew)
+      smpEncodingTest (aBinaryConnReq contactAddress2queuesNew)
+      smpEncodingTest (aBinaryConnReq contactAddressV6)
+      smpEncodingTest (aBinaryConnReq contactAddressClientData)
     it "should serialize / parse short links" $ do
       CSLContact SLSServer CCTContact srv (LinkKey "0123456789abcdef0123456789abcdef") #==# "https://smp.simplex.im/a#MDEyMzQ1Njc4OWFiY2RlZjAxMjM0NTY3ODlhYmNkZWY?h=jjbyvoemxysm7qxap7m5d5m35jzv5qq6gnlv7s4rsn7tdwwmuqciwpid.onion&p=5223&c=1234-w"
       CSLContact SLSServer CCTGroup srv (LinkKey "0123456789abcdef0123456789abcdef") #==# "https://smp.simplex.im/g#MDEyMzQ1Njc4OWFiY2RlZjAxMjM0NTY3ODlhYmNkZWY?h=jjbyvoemxysm7qxap7m5d5m35jzv5qq6gnlv7s4rsn7tdwwmuqciwpid.onion&p=5223&c=1234-w"
@@ -343,6 +352,11 @@ connectionRequestTests =
       Right (inv' :: ConnShortLink 'CMInvitation) <- pure $ strDecode "https://localhost/i#tnUaHYp8saREmyEHR93SBpl8ySHBchOt/LJ1ZQUzxH9Udb0jw5wmJACv5o6oe8e7BsX_hUCUMTSY"
       shortenShortLink [presetSrv] inv `shouldBe` inv'
       restoreShortLink [presetSrv] inv' `shouldBe` inv
+    it "should serialize and parse service RPC agent messages" $ do
+      let qInfo = SMPQueueInfo currentSMPClientVersion queueAddr
+      smpEncodingTest $ AgentServiceRequest [qInfo] Nothing "service request payload"
+      smpEncodingTest $ AgentServiceResponse "service response payload"
+      smpEncodingTest $ AgentRejection "rejected: not allowed"
   where
     smpEncodingTest :: (Encoding a, Eq a, Show a, HasCallStack) => a -> Expectation
     smpEncodingTest a = smpDecode (smpEncode a) `shouldBe` Right a

tests/AgentTests/DoubleRatchetTests.hs

@@ -39,8 +39,7 @@ doubleRatchetTests :: Spec
 doubleRatchetTests = do
   describe "double-ratchet encryption/decryption" $ do
     it "should serialize and parse message header" $ do
-      testAlgs $ testMessageHeader kdfX3DHE2EEncryptVersion
-      testAlgs $ testMessageHeader $ max pqRatchetE2EEncryptVersion currentE2EEncryptVersion
+      testAlgs $ testMessageHeader currentE2EEncryptVersion
     describe "message tests" $ runMessageTests initRatchets False
     it "should encode/decode ratchet as JSON" $ do
       testAlgs testKeyJSON
@@ -90,18 +89,15 @@ paddedMsgLen :: Int
 paddedMsgLen = 100
 
 fullMsgLen :: Ratchet a -> Int
-fullMsgLen Ratchet {rcSupportKEM, rcVersion} = headerLenLength + fullHeaderLen v rcSupportKEM + C.authTagSize + paddedMsgLen
+fullMsgLen Ratchet {rcSupportKEM} = headerLenLength + fullHeaderLen rcSupportKEM + C.authTagSize + paddedMsgLen
   where
-    v = current rcVersion
-    headerLenLength
-      | v >= pqRatchetE2EEncryptVersion = 3 -- two bytes are added because of two Large used in new encoding
-      | otherwise = 1
+    headerLenLength = 3 -- two bytes are added because of two Large used in new encoding
 
 testMessageHeader :: forall a. AlgorithmI a => VersionE2E -> C.SAlgorithm a -> Expectation
 testMessageHeader v _ = do
   (k, _) <- atomically . C.generateKeyPair @a =<< C.newRandom
   let hdr = MsgHeader {msgMaxVersion = v, msgDHRs = k, msgKEM = Nothing, msgPN = 0, msgNs = 0}
-  parseAll (msgHeaderP v) (encodeMsgHeader v hdr) `shouldBe` Right hdr
+  smpDecode (smpEncode hdr) `shouldBe` Right hdr
 
 testKEMParams :: Expectation
 testKEMParams = do
@@ -119,15 +115,15 @@ testMessageHeaderKEM _ = do
   g <- C.newRandom
   (k, _) <- atomically $ C.generateKeyPair @a g
   (kem, _) <- sntrup761Keypair g
-  let msgMaxVersion = max pqRatchetE2EEncryptVersion currentE2EEncryptVersion
+  let msgMaxVersion = currentE2EEncryptVersion
       msgKEM = Just . ARKP SRKSProposed $ RKParamsProposed kem
       hdr = MsgHeader {msgMaxVersion, msgDHRs = k, msgKEM, msgPN = 0, msgNs = 0}
-  parseAll (msgHeaderP msgMaxVersion) (encodeMsgHeader msgMaxVersion hdr) `shouldBe` Right hdr
+  smpDecode (smpEncode hdr) `shouldBe` Right hdr
   (kem', _) <- sntrup761Keypair g
   (ct, _) <- sntrup761Enc g kem
   let msgKEM' = Just . ARKP SRKSAccepted $ RKParamsAccepted ct kem'
       hdr' = MsgHeader {msgMaxVersion, msgDHRs = k, msgKEM = msgKEM', msgPN = 0, msgNs = 0}
-  parseAll (msgHeaderP msgMaxVersion) (encodeMsgHeader msgMaxVersion hdr') `shouldBe` Right hdr'
+  smpDecode (smpEncode hdr') `shouldBe` Right hdr'
 
 pattern Decrypted :: ByteString -> Either CryptoError (Either CryptoError ByteString)
 pattern Decrypted msg <- Right (Right msg)
@@ -380,85 +376,85 @@ testEncodeDecode x = do
 testX3dh :: forall a. (AlgorithmI a, DhAlgorithm a) => C.SAlgorithm a -> IO ()
 testX3dh _ = do
   g <- C.newRandom
-  let v = max pqRatchetE2EEncryptVersion currentE2EEncryptVersion
-  (pkBob1, pkBob2, Nothing, AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams @a g v Nothing
-  (pkAlice1, pkAlice2, Nothing, e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOff
-  let paramsBob = pqX3dhSnd pkBob1 pkBob2 Nothing e2eAlice
-  paramsAlice <- runExceptT $ pqX3dhRcv pkAlice1 pkAlice2 Nothing e2eBob
+  let v = currentE2EEncryptVersion
+  (pksBob@(_, _, Nothing), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams @a g v Nothing
+  (pksAlice@(_, _, Nothing), e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOff
+  let paramsBob = pqX3dhSnd pksBob e2eAlice
+  paramsAlice <- runExceptT $ pqX3dhRcv pksAlice e2eBob
   paramsAlice `shouldBe` paramsBob
 
 testX3dhV1 :: forall a. (AlgorithmI a, DhAlgorithm a) => C.SAlgorithm a -> IO ()
 testX3dhV1 _ = do
   g <- C.newRandom
-  (pkBob1, pkBob2, Nothing, AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams @a g (VersionE2E 1) Nothing
-  (pkAlice1, pkAlice2, Nothing, e2eAlice) <- liftIO $ generateRcvE2EParams @a g (VersionE2E 1) PQSupportOff
-  let paramsBob = pqX3dhSnd pkBob1 pkBob2 Nothing e2eAlice
-  paramsAlice <- runExceptT $ pqX3dhRcv pkAlice1 pkAlice2 Nothing e2eBob
+  (pksBob@(_, _, Nothing), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams @a g (VersionE2E 1) Nothing
+  (pksAlice@(_, _, Nothing), e2eAlice) <- liftIO $ generateRcvE2EParams @a g (VersionE2E 1) PQSupportOff
+  let paramsBob = pqX3dhSnd pksBob e2eAlice
+  paramsAlice <- runExceptT $ pqX3dhRcv pksAlice e2eBob
   paramsAlice `shouldBe` paramsBob
 
 testPqX3dhProposeInReply :: forall a. (AlgorithmI a, DhAlgorithm a) => C.SAlgorithm a -> IO ()
 testPqX3dhProposeInReply _ = do
   g <- C.newRandom
-  let v = max pqRatchetE2EEncryptVersion currentE2EEncryptVersion
+  let v = currentE2EEncryptVersion
   -- initiate (no KEM)
-  (pkAlice1, pkAlice2, Nothing, e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOff
+  (pksAlice@(_, _, Nothing), e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOff
   -- propose KEM in reply
-  (pkBob1, pkBob2, pKemBob_@(Just _), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams @a g v (Just $ AUseKEM SRKSProposed ProposeKEM)
-  Right paramsBob <- pure $ pqX3dhSnd pkBob1 pkBob2 pKemBob_ e2eAlice
-  Right paramsAlice <- runExceptT $ pqX3dhRcv pkAlice1 pkAlice2 Nothing e2eBob
+  (pksBob@(_, _, Just _), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams @a g v (Just $ AUseKEM SRKSProposed ProposeKEM)
+  Right paramsBob <- pure $ pqX3dhSnd pksBob e2eAlice
+  Right paramsAlice <- runExceptT $ pqX3dhRcv pksAlice e2eBob
   paramsAlice `compatibleRatchets` paramsBob
 
 testPqX3dhProposeAccept :: forall a. (AlgorithmI a, DhAlgorithm a) => C.SAlgorithm a -> IO ()
 testPqX3dhProposeAccept _ = do
   g <- C.newRandom
-  let v = max pqRatchetE2EEncryptVersion currentE2EEncryptVersion
+  let v = currentE2EEncryptVersion
   -- initiate (propose KEM)
-  (pkAlice1, pkAlice2, pKemAlice_@(Just _), e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOn
+  (pksAlice@(_, _, Just _), e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOn
   E2ERatchetParams _ _ _ (Just (RKParamsProposed aliceKem)) <- pure e2eAlice
   -- accept KEM
-  (pkBob1, pkBob2, pKemBob_@(Just _), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams @a g v (Just $ AUseKEM SRKSAccepted $ AcceptKEM aliceKem)
-  Right paramsBob <- pure $ pqX3dhSnd pkBob1 pkBob2 pKemBob_ e2eAlice
-  Right paramsAlice <- runExceptT $ pqX3dhRcv pkAlice1 pkAlice2 pKemAlice_ e2eBob
+  (pksBob@(_, _, Just _), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams @a g v (Just $ AUseKEM SRKSAccepted $ AcceptKEM aliceKem)
+  Right paramsBob <- pure $ pqX3dhSnd pksBob e2eAlice
+  Right paramsAlice <- runExceptT $ pqX3dhRcv pksAlice e2eBob
   paramsAlice `compatibleRatchets` paramsBob
 
 testPqX3dhProposeReject :: forall a. (AlgorithmI a, DhAlgorithm a) => C.SAlgorithm a -> IO ()
 testPqX3dhProposeReject _ = do
   g <- C.newRandom
-  let v = max pqRatchetE2EEncryptVersion currentE2EEncryptVersion
+  let v = currentE2EEncryptVersion
   -- initiate (propose KEM)
-  (pkAlice1, pkAlice2, pKemAlice_@(Just _), e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOn
+  (pksAlice@(_, _, Just _), e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOn
   E2ERatchetParams _ _ _ (Just (RKParamsProposed _)) <- pure e2eAlice
   -- reject KEM
-  (pkBob1, pkBob2, Nothing, AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams @a g v Nothing
-  Right paramsBob <- pure $ pqX3dhSnd pkBob1 pkBob2 Nothing e2eAlice
-  Right paramsAlice <- runExceptT $ pqX3dhRcv pkAlice1 pkAlice2 pKemAlice_ e2eBob
+  (pksBob@(_, _, Nothing), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams @a g v Nothing
+  Right paramsBob <- pure $ pqX3dhSnd pksBob e2eAlice
+  Right paramsAlice <- runExceptT $ pqX3dhRcv pksAlice e2eBob
   paramsAlice `compatibleRatchets` paramsBob
 
 testPqX3dhAcceptWithoutProposalError :: forall a. (AlgorithmI a, DhAlgorithm a) => C.SAlgorithm a -> IO ()
 testPqX3dhAcceptWithoutProposalError _ = do
   g <- C.newRandom
-  let v = max pqRatchetE2EEncryptVersion currentE2EEncryptVersion
+  let v = currentE2EEncryptVersion
   -- initiate (no KEM)
-  (pkAlice1, pkAlice2, Nothing, e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOff
+  (pksAlice@(_, _, Nothing), e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOff
   E2ERatchetParams _ _ _ Nothing <- pure e2eAlice
   -- incorrectly accept KEM
   -- we don't have key in proposal, so we just generate it
   (k, _) <- sntrup761Keypair g
-  (pkBob1, pkBob2, pKemBob_@(Just _), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams @a g v (Just $ AUseKEM SRKSAccepted $ AcceptKEM k)
-  pqX3dhSnd pkBob1 pkBob2 pKemBob_ e2eAlice `shouldBe` Left C.CERatchetKEMState
-  runExceptT (pqX3dhRcv pkAlice1 pkAlice2 Nothing e2eBob) `shouldReturn` Left C.CERatchetKEMState
+  (pksBob@(_, _, Just _), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams @a g v (Just $ AUseKEM SRKSAccepted $ AcceptKEM k)
+  pqX3dhSnd pksBob e2eAlice `shouldBe` Left C.CERatchetKEMState
+  runExceptT (pqX3dhRcv pksAlice e2eBob) `shouldReturn` Left C.CERatchetKEMState
 
 testPqX3dhProposeAgain :: forall a. (AlgorithmI a, DhAlgorithm a) => C.SAlgorithm a -> IO ()
 testPqX3dhProposeAgain _ = do
   g <- C.newRandom
-  let v = max pqRatchetE2EEncryptVersion currentE2EEncryptVersion
+  let v = currentE2EEncryptVersion
   -- initiate (propose KEM)
-  (pkAlice1, pkAlice2, pKemAlice_@(Just _), e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOn
+  (pksAlice@(_, _, Just _), e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOn
   E2ERatchetParams _ _ _ (Just (RKParamsProposed _)) <- pure e2eAlice
   -- propose KEM again in reply - this is not an error
-  (pkBob1, pkBob2, pKemBob_@(Just _), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams @a g v (Just $ AUseKEM SRKSProposed ProposeKEM)
-  Right paramsBob <- pure $ pqX3dhSnd pkBob1 pkBob2 pKemBob_ e2eAlice
-  Right paramsAlice <- runExceptT $ pqX3dhRcv pkAlice1 pkAlice2 pKemAlice_ e2eBob
+  (pksBob@(_, _, Just _), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams @a g v (Just $ AUseKEM SRKSProposed ProposeKEM)
+  Right paramsBob <- pure $ pqX3dhSnd pksBob e2eAlice
+  Right paramsAlice <- runExceptT $ pqX3dhRcv pksAlice e2eBob
   paramsAlice `compatibleRatchets` paramsBob
 
 compatibleRatchets :: (RatchetInitParams, x) -> (RatchetInitParams, x) -> Expectation
@@ -514,11 +510,11 @@ withRatchets_ initRatchets_ test = do
 initRatchets :: (AlgorithmI a, DhAlgorithm a) => IO (Ratchet a, Ratchet a, Encrypt a, Decrypt a, EncryptDecryptSpec a)
 initRatchets = do
   g <- C.newRandom
-  let v = max pqRatchetE2EEncryptVersion currentE2EEncryptVersion
-  (pkBob1, pkBob2, _pKemParams@Nothing, AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams g v Nothing
-  (pkAlice1, pkAlice2, _pKem@Nothing, e2eAlice) <- liftIO $ generateRcvE2EParams g v PQSupportOff
-  Right paramsBob <- pure $ pqX3dhSnd pkBob1 pkBob2 Nothing e2eAlice
-  Right paramsAlice <- runExceptT $ pqX3dhRcv pkAlice1 pkAlice2 Nothing e2eBob
+  let v = currentE2EEncryptVersion
+  (pksBob@(_, _, Nothing), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams g v Nothing
+  (pksAlice@(_, pkAlice2, Nothing), e2eAlice) <- liftIO $ generateRcvE2EParams g v PQSupportOff
+  Right paramsBob <- pure $ pqX3dhSnd pksBob e2eAlice
+  Right paramsAlice <- runExceptT $ pqX3dhRcv pksAlice e2eBob
   (_, pkBob3) <- atomically $ C.generateKeyPair g
   let vs = testRatchetVersions
       bob = initSndRatchet vs (C.publicKey pkAlice2) pkBob3 paramsBob
@@ -528,14 +524,14 @@ initRatchets = do
 initRatchetsKEMProposed :: forall a. (AlgorithmI a, DhAlgorithm a) => IO (Ratchet a, Ratchet a, Encrypt a, Decrypt a, EncryptDecryptSpec a)
 initRatchetsKEMProposed = do
   g <- C.newRandom
-  let v = max pqRatchetE2EEncryptVersion currentE2EEncryptVersion
+  let v = currentE2EEncryptVersion
   -- initiate (no KEM)
-  (pkAlice1, pkAlice2, Nothing, e2eAlice) <- liftIO $ generateRcvE2EParams g v PQSupportOff
+  (pksAlice@(_, pkAlice2, Nothing), e2eAlice) <- liftIO $ generateRcvE2EParams g v PQSupportOff
   -- propose KEM in reply
   let useKem = AUseKEM SRKSProposed ProposeKEM
-  (pkBob1, pkBob2, pKemParams_@(Just _), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams g v (Just useKem)
-  Right paramsBob <- pure $ pqX3dhSnd pkBob1 pkBob2 pKemParams_ e2eAlice
-  Right paramsAlice <- runExceptT $ pqX3dhRcv pkAlice1 pkAlice2 Nothing e2eBob
+  (pksBob@(_, _, Just _), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams g v (Just useKem)
+  Right paramsBob <- pure $ pqX3dhSnd pksBob e2eAlice
+  Right paramsAlice <- runExceptT $ pqX3dhRcv pksAlice e2eBob
   (_, pkBob3) <- atomically $ C.generateKeyPair g
   let vs = testRatchetVersions
       bob = initSndRatchet vs (C.publicKey pkAlice2) pkBob3 paramsBob
@@ -545,15 +541,15 @@ initRatchetsKEMProposed = do
 initRatchetsKEMAccepted :: forall a. (AlgorithmI a, DhAlgorithm a) => IO (Ratchet a, Ratchet a, Encrypt a, Decrypt a, EncryptDecryptSpec a)
 initRatchetsKEMAccepted = do
   g <- C.newRandom
-  let v = max pqRatchetE2EEncryptVersion currentE2EEncryptVersion
+  let v = currentE2EEncryptVersion
   -- initiate (propose)
-  (pkAlice1, pkAlice2, pKem_@(Just _), e2eAlice) <- liftIO $ generateRcvE2EParams g v PQSupportOn
+  (pksAlice@(_, pkAlice2, Just _), e2eAlice) <- liftIO $ generateRcvE2EParams g v PQSupportOn
   E2ERatchetParams _ _ _ (Just (RKParamsProposed aliceKem)) <- pure e2eAlice
   -- accept
   let useKem = AUseKEM SRKSAccepted (AcceptKEM aliceKem)
-  (pkBob1, pkBob2, pKemParams_@(Just _), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams g v (Just useKem)
-  Right paramsBob <- pure $ pqX3dhSnd pkBob1 pkBob2 pKemParams_ e2eAlice
-  Right paramsAlice <- runExceptT $ pqX3dhRcv pkAlice1 pkAlice2 pKem_ e2eBob
+  (pksBob@(_, _, Just _), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams g v (Just useKem)
+  Right paramsBob <- pure $ pqX3dhSnd pksBob e2eAlice
+  Right paramsAlice <- runExceptT $ pqX3dhRcv pksAlice e2eBob
   (_, pkBob3) <- atomically $ C.generateKeyPair g
   let vs = testRatchetVersions
       bob = initSndRatchet vs (C.publicKey pkAlice2) pkBob3 paramsBob
@@ -563,14 +559,14 @@ initRatchetsKEMAccepted = do
 initRatchetsKEMProposedAgain :: forall a. (AlgorithmI a, DhAlgorithm a) => IO (Ratchet a, Ratchet a, Encrypt a, Decrypt a, EncryptDecryptSpec a)
 initRatchetsKEMProposedAgain = do
   g <- C.newRandom
-  let v = max pqRatchetE2EEncryptVersion currentE2EEncryptVersion
+  let v = currentE2EEncryptVersion
   -- initiate (propose KEM)
-  (pkAlice1, pkAlice2, pKem_@(Just _), e2eAlice) <- liftIO $ generateRcvE2EParams g v PQSupportOn
+  (pksAlice@(_, pkAlice2, Just _), e2eAlice) <- liftIO $ generateRcvE2EParams g v PQSupportOn
   -- propose KEM again in reply
   let useKem = AUseKEM SRKSProposed ProposeKEM
-  (pkBob1, pkBob2, pKemParams_@(Just _), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams g v (Just useKem)
-  Right paramsBob <- pure $ pqX3dhSnd pkBob1 pkBob2 pKemParams_ e2eAlice
-  Right paramsAlice <- runExceptT $ pqX3dhRcv pkAlice1 pkAlice2 pKem_ e2eBob
+  (pksBob@(_, _, Just _), AE2ERatchetParams _ e2eBob) <- liftIO $ generateSndE2EParams g v (Just useKem)
+  Right paramsBob <- pure $ pqX3dhSnd pksBob e2eAlice
+  Right paramsAlice <- runExceptT $ pqX3dhRcv pksAlice e2eBob
   (_, pkBob3) <- atomically $ C.generateKeyPair g
   let vs = testRatchetVersions
       bob = initSndRatchet vs (C.publicKey pkAlice2) pkBob3 paramsBob

tests/AgentTests/EqInstances.hs

@@ -5,9 +5,10 @@
 module AgentTests.EqInstances where
 
 import Data.Type.Equality
-import Simplex.Messaging.Agent.Protocol (ShortLinkCreds (..))
+import Simplex.Messaging.Agent.Protocol (ABinaryConnectionRequestUri (..), AMessage (..), AMessageReceipt (..), AgentMessage (..), APrivHeader (..), ShortLinkCreds (..))
 import Simplex.Messaging.Agent.Store
 import Simplex.Messaging.Client (ProxiedRelay (..))
+import Simplex.Messaging.Server.Information
 
 instance (Eq rq, Eq sq) => Eq (SomeConn' rq sq) where
   SomeConn d c == SomeConn d' c' = case testEquality d d' of
@@ -31,3 +32,30 @@ deriving instance Eq ShortLinkCreds
 deriving instance Show ProxiedRelay
 
 deriving instance Eq ProxiedRelay
+
+instance Eq ABinaryConnectionRequestUri where
+  ABCR m cr == ABCR m' cr' = case testEquality m m' of
+    Just Refl -> cr == cr'
+    _ -> False
+
+deriving instance Show ABinaryConnectionRequestUri
+
+deriving instance Eq APrivHeader
+
+deriving instance Eq AMessageReceipt
+
+deriving instance Eq AMessage
+
+deriving instance Eq AgentMessage
+
+deriving instance Eq Entity
+
+deriving instance Eq HostingType
+
+deriving instance Eq PGPKey
+
+deriving instance Eq ServerConditions
+
+deriving instance Eq ServerContactAddress
+
+deriving instance Eq ServerPublicInfo

tests/AgentTests/NotificationTests.hs

@@ -17,7 +17,8 @@ module AgentTests.NotificationTests where
 
 -- import Control.Logger.Simple (LogConfig (..), LogLevel (..), setLogLevel, withGlobalLogging)
 import AgentTests.FunctionalAPITests
-  ( agentCfgVPrevPQ,
+  ( agentCfgV7,
+    agentCfgVPrevPQ,
     createConnection,
     exchangeGreetings,
     get,
@@ -28,6 +29,7 @@ import AgentTests.FunctionalAPITests
     runRight_,
     sendMessage,
     switchComplete,
+    fastSwitchComplete,
     testServerMatrix2,
     withAgent,
     withAgentClients2,
@@ -82,6 +84,7 @@ import Simplex.Messaging.Parsers (parseAll)
 import Simplex.Messaging.Protocol (ErrorType (AUTH), NetworkError (..), MsgFlags (MsgFlags), NMsgMeta (..), NtfServer, ProtocolServer (..), SMPMsgMeta (..), SubscriptionMode (..))
 import qualified Simplex.Messaging.Protocol as SMP
 import Simplex.Messaging.Server.Env.STM (AStoreType (..), ServerConfig (..))
+import Simplex.Messaging.Server.Information (ServerPublicInfo (..))
 import Simplex.Messaging.Transport (ASrvTransport)
 import Simplex.Messaging.Transport.Server (TransportServerConfig (..))
 import System.Process (callCommand)
@@ -134,10 +137,10 @@ notificationTests ps@(t, _) = do
       withAPNSMockServer $ \apns ->
         testNtfTokenReRegisterInvalidOnCheck t apns
   describe "notification server tests" $ do
-    it "should pass" $ testRunNTFServerTests t testNtfServer `shouldReturn` Nothing
+    it "should pass" $ testRunNTFServerTests t testNtfServer `shouldReturn` Right Nothing
     let srv1 = testNtfServer {keyHash = "1234"}
     it "should fail with incorrect fingerprint" $ do
-      testRunNTFServerTests t srv1 `shouldReturn` Just (ProtocolTestFailure TSConnect $ BROKER (B.unpack $ strEncode srv1) $ NETWORK NEUnknownCAError)
+      testRunNTFServerTests t srv1 `shouldReturn` Left (ProtocolTestFailure TSConnect $ BROKER (B.unpack $ strEncode srv1) $ NETWORK NEUnknownCAError)
   describe "Managing notification subscriptions" $ do
     describe "should create notification subscription for existing connection" $
       testNtfMatrix ps testNotificationSubscriptionExistingConnection
@@ -163,10 +166,14 @@ notificationTests ps@(t, _) = do
     it "should resume batched subscriptions after SMP server is restarted" $
       withAPNSMockServer $ \apns ->
         withNtfServer t $ testNotificationsSMPRestartBatch 50 ps apns
-  describe "should switch notifications to the new queue" $
+  describe "should switch notifications to the new queue (slow rotation)" $
     testServerMatrix2 ps $ \servers ->
       withAPNSMockServer $ \apns ->
-        withNtfServer t $ testSwitchNotifications servers apns
+        withNtfServer t $ testSwitchNotifications agentCfgV7 switchComplete servers apns
+  describe "should switch notifications to the new queue (fast rotation)" $
+    testServerMatrix2 ps $ \servers ->
+      withAPNSMockServer $ \apns ->
+        withNtfServer t $ testSwitchNotifications agentCfg fastSwitchComplete servers apns
   it "should keep sending notifications for old token" $
     withSmpServer ps $
       withAPNSMockServer $ \apns ->
@@ -184,10 +191,10 @@ testNtfMatrix ps@(_, msType) runTest = do
   describe "next and current" $ do
     it "curr servers; curr clients" $ runNtfTestCfg ps 1 cfg' ntfServerCfg agentCfg agentCfg runTest
     it "curr servers; prev clients" $ runNtfTestCfg ps 1 cfg' ntfServerCfg agentCfgVPrevPQ agentCfgVPrevPQ runTest
-    it "prev servers; prev clients" $ runNtfTestCfg ps 1 cfgVPrev' ntfServerCfgVPrev agentCfgVPrevPQ agentCfgVPrevPQ runTest
-    it "prev servers; curr clients" $ runNtfTestCfg ps 1 cfgVPrev' ntfServerCfgVPrev agentCfg agentCfg runTest
+    it "prev servers; prev clients" $ runNtfTestCfg ps 1 cfgVPrev' ntfServerCfg agentCfgVPrevPQ agentCfgVPrevPQ runTest
+    it "prev servers; curr clients" $ runNtfTestCfg ps 1 cfgVPrev' ntfServerCfg agentCfg agentCfg runTest
     -- servers can be upgraded in any order
-    it "servers: curr SMP, prev NTF; prev clients" $ runNtfTestCfg ps 1 cfg' ntfServerCfgVPrev agentCfgVPrevPQ agentCfgVPrevPQ runTest
+    -- it "servers: curr SMP, prev NTF; prev clients" $ runNtfTestCfg ps 1 cfg' ntfServerCfg agentCfgVPrevPQ agentCfgVPrevPQ runTest
     it "servers: prev SMP, curr NTF; prev clients" $ runNtfTestCfg ps 1 cfgVPrev' ntfServerCfg agentCfgVPrevPQ agentCfgVPrevPQ runTest
     -- one of two clients can be upgraded
     it "servers: curr SMP, curr NTF; clients: curr/prev" $ runNtfTestCfg ps 1 cfg' ntfServerCfg agentCfg agentCfgVPrevPQ runTest
@@ -536,11 +543,11 @@ testNtfTokenReRegisterInvalidOnCheck t apns = do
       NTActive <- checkNtfToken a tkn1
       pure ()
 
-testRunNTFServerTests :: ASrvTransport -> NtfServer -> IO (Maybe ProtocolTestFailure)
+testRunNTFServerTests :: ASrvTransport -> NtfServer -> IO (Either ProtocolTestFailure (Maybe (Either String ServerPublicInfo)))
 testRunNTFServerTests t srv =
   withNtfServer t $
     withAgent 1 agentCfg initAgentServers testDB $ \a ->
-      testProtocolServer a NRMInteractive 1 $ ProtoServerWithAuth srv Nothing
+      testProtocolServer a NRMInteractive 1 (ProtoServerWithAuth srv Nothing)
 
 testNotificationSubscriptionExistingConnection :: APNSMockServer -> AgentMsgId -> AgentClient -> AgentClient -> IO ()
 testNotificationSubscriptionExistingConnection apns baseId alice@AgentClient {agentEnv = Env {config = aliceCfg, store}} bob = do
@@ -867,9 +874,9 @@ testNotificationsSMPRestartBatch n ps@(t, ASType qsType _) apns =
         killThread t1
         pure res
 
-testSwitchNotifications :: InitialAgentServers -> APNSMockServer -> IO ()
-testSwitchNotifications servers apns =
-  withAgentClientsCfgServers2 agentCfg agentCfg servers $ \a b -> runRight_ $ do
+testSwitchNotifications :: AgentConfig -> (AgentClient -> ByteString -> AgentClient -> ByteString -> ExceptT AgentErrorType IO ()) -> InitialAgentServers -> APNSMockServer -> IO ()
+testSwitchNotifications cfg completeSwitch servers apns =
+  withAgentClientsCfgServers2 cfg cfg servers $ \a b -> runRight_ $ do
     (aId, bId) <- makeConnection a b
     exchangeGreetings a bId b aId
     _ <- registerTestToken a "abcd" NMInstant apns
@@ -882,7 +889,7 @@ testSwitchNotifications servers apns =
           ackMessage a bId msgId Nothing
     testMessage "hello"
     _ <- switchConnectionAsync a "" bId
-    switchComplete a bId b aId
+    completeSwitch a bId b aId
     liftIO $ threadDelay 500000
     testMessage "hello again"
 

tests/AgentTests/ResolveNameTests.hs

@@ -0,0 +1,152 @@
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# LANGUAGE GADTs #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedLists #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE TypeApplications #-}
+{-# OPTIONS_GHC -fno-warn-ambiguous-fields #-}
+
+module AgentTests.ResolveNameTests (resolveNameTests) where
+
+import AgentTests.FunctionalAPITests (withAgent)
+import Control.Monad.Except (runExceptT)
+import qualified Data.Aeson as J
+import qualified Data.ByteString.Lazy as LB
+import Data.List (isInfixOf)
+import Network.HTTP.Types (Status, status200, status404, status502)
+import NamesResolverServer (memCfg, memCfg2, memProxyCfg, withNames)
+import qualified NamesResolverServer as NRS
+import SMPAgentClient
+import SMPClient
+import SMPNamesTests (testNameRecord)
+import Simplex.Messaging.Agent (resolveSimplexName)
+import Simplex.Messaging.Agent.Client (AgentClient)
+import Simplex.Messaging.Agent.Env.SQLite (InitialAgentServers (..), ServerCfg, ServerRoles (..), presetServerCfg)
+import Simplex.Messaging.Agent.Protocol (AgentErrorType (..))
+import Simplex.Messaging.Client (SMPProxyFallback (..), SMPProxyMode (..), pattern NRMInteractive)
+import Simplex.Messaging.Protocol (SMPServer)
+import qualified Simplex.Messaging.Protocol as SMP
+import Simplex.Messaging.SimplexName (SimplexDomain (..), SimplexTLD (..))
+import Simplex.Messaging.Transport
+import Test.Hspec hiding (fit, it)
+import Util (it)
+
+nameSrvCfg :: SMPServer -> ServerCfg 'SMP.PSMP
+nameSrvCfg = presetServerCfg True ServerRoles {storage = True, proxy = False, names = True} (Just 1) . SMP.noAuthSrv
+
+proxySrvCfg :: SMPServer -> ServerCfg 'SMP.PSMP
+proxySrvCfg = presetServerCfg True ServerRoles {storage = True, proxy = True, names = False} (Just 1) . SMP.noAuthSrv
+
+oneSrv :: ServerCfg 'SMP.PSMP -> InitialAgentServers
+oneSrv cfg_ = (initAgentServersProxy_ SPMNever SPFProhibit) {smp = [(1, [cfg_])]}
+
+withDirectResolver :: (Status, LB.ByteString) -> (AgentClient -> IO a) -> IO a
+withDirectResolver (st, body) k =
+  NRS.withResolverServer (NRS.resolveResp st body) $ \port _ ->
+    withSmpServerConfigOn (transport @TLS) (withNames port memCfg) testPort $ \_ ->
+      withAgent 1 agentCfg (oneSrv (nameSrvCfg testSMPServer)) testDB k
+
+withProxyAndResolver :: (Status, LB.ByteString) -> (AgentClient -> IO a) -> IO a
+withProxyAndResolver (st, body) k =
+  NRS.withResolverServer (NRS.resolveResp st body) $ \port _ ->
+    withSmpServerConfigOn (transport @TLS) memProxyCfg testPort $ \_ ->
+      withSmpServerConfigOn (transport @TLS) (withNames port memCfg2) testPort2 $ \_ ->
+        withAgent 1 agentCfg proxyServers testDB k
+  where
+    -- only testSMPServer2 (the resolver) has the names role; testSMPServer is the proxy
+    proxyServers = (initAgentServersProxy_ SPMAlways SPFProhibit) {smp = [(1, [proxySrvCfg testSMPServer, nameSrvCfg testSMPServer2])]}
+
+withNoResolver :: (AgentClient -> IO a) -> IO a
+withNoResolver k =
+  withSmpServerConfigOn (transport @TLS) memCfg testPort $ \_ ->
+    withAgent 1 agentCfg (oneSrv (nameSrvCfg testSMPServer)) testDB k
+
+withNoNameServers :: (AgentClient -> IO a) -> IO a
+withNoNameServers k = withAgent 1 agentCfg (oneSrv (proxySrvCfg testSMPServer)) testDB k
+
+resolveNameTests :: Spec
+resolveNameTests = do
+  describe "direct path (SPMNever)" $
+    it "404 propagates as SMP host (NAME NOT_FOUND)" testDirectNotFound
+  describe "proxy path (SPMAlways)" $
+    it "404 from resolver propagates via proxy as SMP <proxyHost> (NAME NOT_FOUND)" testProxyNotFound
+  describe "TLDTesting path" $
+    it "NAME NOT_FOUND for TLDTesting too" testTestingTldNotFound
+  describe "TLDWeb path" $
+    it "NAME NOT_FOUND for TLDWeb too" testWebTldNotFound
+  describe "no resolver configured" $
+    it "answers NAME NO_RESOLVER" testNoResolver
+  describe "no names servers (names role off everywhere)" $
+    it "fails agent-side with NO_NAME_SERVERS" testNoNameServers
+  describe "backing resolver failure" $
+    it "surfaces as SMP host (NAME (RESOLVER ..))" testBackendError
+  describe "success path" $
+    it "returns NameRecord" testDirectSuccess
+
+testDirectNotFound :: HasCallStack => IO ()
+testDirectNotFound =
+  withDirectResolver (status404, "{}") $ \c -> do
+    r <- runExceptT $ resolveSimplexName c NRMInteractive 1 (SimplexDomain TLDSimplex "alice" [])
+    case r of
+      Left (SMP _ (SMP.NAME SMP.NOT_FOUND)) -> pure ()
+      _ -> expectationFailure $ "expected Left (SMP _ (NAME NOT_FOUND)), got: " <> show r
+
+testProxyNotFound :: HasCallStack => IO ()
+testProxyNotFound =
+  withProxyAndResolver (status404, "{}") $ \c -> do
+    r <- runExceptT $ resolveSimplexName c NRMInteractive 1 (SimplexDomain TLDSimplex "alice" [])
+    case r of
+      Left (SMP host (SMP.NAME SMP.NOT_FOUND)) | testPort `isInfixOf` host -> pure ()
+      _ -> expectationFailure $ "expected Left (SMP <proxyHost:" <> testPort <> "> (NAME NOT_FOUND)), got: " <> show r
+
+testTestingTldNotFound :: HasCallStack => IO ()
+testTestingTldNotFound =
+  withDirectResolver (status404, "{}") $ \c -> do
+    r <- runExceptT $ resolveSimplexName c NRMInteractive 1 (SimplexDomain TLDTesting "bob" [])
+    case r of
+      Left (SMP _ (SMP.NAME SMP.NOT_FOUND)) -> pure ()
+      _ -> expectationFailure $ "expected Left (SMP _ (NAME NOT_FOUND)), got: " <> show r
+
+testWebTldNotFound :: HasCallStack => IO ()
+testWebTldNotFound =
+  withDirectResolver (status404, "{}") $ \c -> do
+    r <- runExceptT $ resolveSimplexName c NRMInteractive 1 (SimplexDomain TLDWeb "example.com" [])
+    case r of
+      Left (SMP _ (SMP.NAME SMP.NOT_FOUND)) -> pure ()
+      _ -> expectationFailure $ "expected Left (SMP _ (NAME NOT_FOUND)), got: " <> show r
+
+testNoResolver :: HasCallStack => IO ()
+testNoResolver =
+  withNoResolver $ \c -> do
+    r <- runExceptT $ resolveSimplexName c NRMInteractive 1 (SimplexDomain TLDSimplex "alice" [])
+    case r of
+      Left (SMP _ (SMP.NAME SMP.NO_RESOLVER)) -> pure ()
+      _ -> expectationFailure $ "expected Left (SMP _ (NAME NO_RESOLVER)), got: " <> show r
+
+testNoNameServers :: HasCallStack => IO ()
+testNoNameServers =
+  withNoNameServers $ \c -> do
+    r <- runExceptT $ resolveSimplexName c NRMInteractive 1 (SimplexDomain TLDSimplex "alice" [])
+    case r of
+      Left NO_NAME_SERVERS -> pure ()
+      _ -> expectationFailure $ "expected Left NO_NAME_SERVERS, got: " <> show r
+
+testBackendError :: HasCallStack => IO ()
+testBackendError =
+  withDirectResolver (status502, "{}") $ \c -> do
+    r <- runExceptT $ resolveSimplexName c NRMInteractive 1 (SimplexDomain TLDSimplex "alice" [])
+    case r of
+      Left (SMP _ (SMP.NAME (SMP.RESOLVER _))) -> pure ()
+      _ -> expectationFailure $ "expected Left (SMP _ (NAME (RESOLVER ..))), got: " <> show r
+
+testDirectSuccess :: HasCallStack => IO ()
+testDirectSuccess =
+  withDirectResolver (status200, J.encode testNameRecord) $ \c -> do
+    r <- runExceptT $ resolveSimplexName c NRMInteractive 1 (SimplexDomain TLDSimplex "alice" [])
+    case r of
+      Right nr -> nr `shouldBe` testNameRecord
+      _ -> expectationFailure $ "expected Right NameRecord, got: " <> show r