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>

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

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+# 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

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+# 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.

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 20, 2026-05-25
+Version 21, 2026-07-05
 
 # Simplex Messaging Protocol (SMP)
 
@@ -107,6 +107,7 @@ This document describes SMP protocol version 20. Versions 1-5 are discontinued.
 - 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
 

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.

simplexmq.cabal

@@ -1,7 +1,7 @@
 cabal-version: 3.0
 
 name:           simplexmq
-version:        7.0.1.0
+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
@@ -152,6 +152,7 @@ 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
@@ -190,6 +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
@@ -242,6 +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:
@@ -266,7 +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

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/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/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

@@ -304,11 +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
@@ -384,6 +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,
@@ -547,6 +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
@@ -592,6 +595,7 @@ newAgentClient clientId InitialAgentServers {smp, ntf, xftp, netCfg, useServices
         clientId,
         agentEnv,
         proxySessTs,
+        serviceRequests,
         smpServersStats,
         xftpServersStats,
         ntfServersStats,
@@ -710,7 +714,7 @@ getSMPProxyClient c@AgentClient {active, smpClients, smpProxiedRelays, workerSeq
       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
@@ -721,6 +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
@@ -1281,7 +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
@@ -1303,8 +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
@@ -1504,9 +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'
@@ -1913,17 +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
@@ -1943,7 +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)
 
@@ -2247,7 +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

@@ -153,6 +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,
@@ -170,6 +172,7 @@ data AgentConfig = AgentConfig
     xftpConsecutiveRetries :: Int,
     xftpMaxRecipientsPerRequest :: Int,
     deleteErrorCount :: Int,
+    keepAddressKeys :: Int,
     ntfCron :: Word16,
     ntfBatchSize :: Int,
     ntfSubFirstCheckInterval :: NominalDiffTime,
@@ -228,6 +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,
@@ -245,6 +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,
@@ -118,6 +121,10 @@ module Simplex.Messaging.Agent.Protocol
     UserConnLinkData (..),
     UserContactData (..),
     UserLinkData (..),
+    AddressRatchetKeys,
+    NewRatchetKeys,
+    DRInvitation (..),
+    RatchetKeyId (..),
     OwnerAuth (..),
     OwnerId,
     ConnectionLink (..),
@@ -151,6 +158,7 @@ module Simplex.Messaging.Agent.Protocol
     ConnectionErrorType (..),
     BrokerErrorType (..),
     SMPAgentError (..),
+    AgentServiceError (..),
     DroppedMsg (..),
     AgentCryptoError (..),
     cryptoErrToSyncState,
@@ -200,6 +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 (($>))
@@ -230,9 +239,11 @@ import Simplex.Messaging.Crypto.Ratchet
   ( InitialKeys (..),
     PQEncryption (..),
     PQSupport,
+    RatchetX448,
     RcvE2ERatchetParams,
     RcvE2ERatchetParamsUri,
     SndE2ERatchetParams,
+    RcvE2EPrivRatchetParams,
     pattern PQSupportOff,
     pattern PQSupportOn,
   )
@@ -289,6 +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
 
@@ -301,29 +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
@@ -331,17 +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)
@@ -393,13 +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
@@ -454,15 +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_
@@ -481,6 +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
@@ -544,6 +555,9 @@ aEventTag = \case
   LDATA {} -> LDATA_
   CONF {} -> CONF_
   REQ {} -> REQ_
+  SREQ {} -> SREQ_
+  SSENT {} -> SSENT_
+  RJCT {} -> RJCT_
   INFO {} -> INFO_
   CON _ -> CON_
   END -> END_
@@ -625,16 +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
@@ -843,6 +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,
@@ -858,6 +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
@@ -873,12 +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
@@ -890,6 +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
@@ -898,12 +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
@@ -919,7 +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
@@ -935,7 +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
@@ -951,8 +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
@@ -961,6 +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
@@ -984,6 +1046,7 @@ data AMsgType
   | QKEY_
   | QUSE_
   | QTEST_
+  | QEND_
   | EREADY_
   deriving (Eq)
 
@@ -997,6 +1060,7 @@ instance Encoding AMsgType where
     QKEY_ -> "QK"
     QUSE_ -> "QU"
     QTEST_ -> "QT"
+    QEND_ -> "QE"
     EREADY_ -> "E"
   smpP =
     A.anyChar >>= \case
@@ -1010,6 +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"
@@ -1034,6 +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)
@@ -1052,6 +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
@@ -1104,6 +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
@@ -1116,6 +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
@@ -1131,11 +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 =
@@ -1143,23 +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} =
@@ -1202,7 +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
@@ -1328,6 +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})
@@ -1433,6 +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) <$> strP
+
 instance Encoding SMPQueueUri where
   smpEncode (SMPQueueUri clientVRange@(VersionRange minV maxV) SMPQueueAddress {smpServer, senderId, dhPublicKey, queueMode})
     -- The condition is for minVersion as earlier clients won't be able to support it.
@@ -1452,16 +1533,30 @@ instance Encoding SMPQueueUri where
 queueModeP :: Parser (Maybe QueueMode)
 queueModeP = Just <$> 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)
 
@@ -1519,9 +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
 
@@ -1733,7 +1831,7 @@ 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')
@@ -1772,7 +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)
@@ -1785,6 +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,
@@ -1792,7 +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)
 
@@ -1870,10 +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
@@ -1920,14 +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)
@@ -2075,7 +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
@@ -2090,8 +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
@@ -2116,6 +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")
@@ -2146,10 +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
@@ -2159,16 +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_
@@ -2200,6 +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)

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") $
@@ -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/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

@@ -227,10 +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_ =
@@ -974,7 +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
@@ -1110,17 +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
@@ -1351,7 +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
@@ -1364,9 +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/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/Ratchet.hs

@@ -37,6 +37,7 @@ module Simplex.Messaging.Crypto.Ratchet
     AUseKEM (..),
     RatchetKEMState (..),
     SRatchetKEMState (..),
+    RatchetKEMStateI (..),
     RcvPrivRKEMParams,
     APrivRKEMParams (..),
     RcvE2ERatchetParamsUri,
@@ -50,8 +51,6 @@ module Simplex.Messaging.Crypto.Ratchet
     VersionRangeE2E,
     pattern VersionE2E,
     RatchetVersions (..),
-    kdfX3DHE2EEncryptVersion,
-    pqRatchetE2EEncryptVersion,
     currentE2EEncryptVersion,
     supportedE2EEncryptVRange,
     generateRcvE2EParams,
@@ -86,8 +85,6 @@ module Simplex.Messaging.Crypto.Ratchet
     RatchetKey (..),
     fullHeaderLen,
     applySMDiff,
-    encodeMsgHeader,
-    msgHeaderP,
   )
 where
 
@@ -101,7 +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)
@@ -131,6 +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
 
@@ -143,17 +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
@@ -237,9 +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)
@@ -260,14 +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
@@ -306,11 +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 #-}
 
@@ -327,25 +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_)
@@ -431,16 +421,14 @@ generateE2EParams g v useKEM_ = do
   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 (RcvE2EPrivRatchetParams a, RcvE2ERatchetParams a)
@@ -473,30 +461,30 @@ data RatchetInitParams = RatchetInitParams
 -- this is used by the peer joining the connection
 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) => 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)
@@ -720,31 +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
@@ -756,26 +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,
@@ -783,15 +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)
@@ -840,15 +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
@@ -897,9 +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 ()
@@ -915,14 +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 =
@@ -950,9 +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,
@@ -975,11 +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)
@@ -1003,7 +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
@@ -1048,7 +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
@@ -1063,7 +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,
@@ -1077,17 +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
@@ -1155,9 +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/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/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/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

@@ -312,18 +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
@@ -1582,7 +1577,7 @@ 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
@@ -1795,13 +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)
@@ -1886,21 +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
@@ -1950,11 +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)
@@ -1972,16 +1962,13 @@ 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_
@@ -2004,8 +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
@@ -2290,19 +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]
@@ -2366,9 +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

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)
@@ -739,9 +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 ()
 
@@ -1377,11 +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
@@ -1444,11 +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
@@ -1459,16 +1460,12 @@ 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)
@@ -1512,8 +1509,8 @@ client
     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
@@ -1980,7 +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
@@ -2157,7 +2154,7 @@ client
                   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 fwdVersion (Right (M.empty, M.empty, M.empty)) t'')
+              _ -> Just . maybe (corrId', entId', ERR INTERNAL) fst <$> lift (processCommand Nothing (Right (M.empty, M.empty, M.empty)) t'')
           stats <- asks serverStats
           incStat $ pMsgFwdsRecv stats
           traverse encodeResp r_

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

@@ -59,7 +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)
@@ -85,7 +85,7 @@ import Simplex.Messaging.Transport (supportedProxyClientSMPRelayVRange, alpnSupp
 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)
@@ -787,12 +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}

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/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/Transport.hs

@@ -46,18 +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 (..),
@@ -114,8 +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)
@@ -140,9 +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)
@@ -173,6 +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
 
@@ -185,29 +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
@@ -227,20 +204,20 @@ 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 20
-
-legacyServerSMPRelayVersion :: VersionSMP
-legacyServerSMPRelayVersion = VersionSMP 6
+currentClientSMPRelayVersion = VersionSMP 21
 
 currentServerSMPRelayVersion :: VersionSMP
-currentServerSMPRelayVersion = VersionSMP 20
+currentServerSMPRelayVersion = VersionSMP 21
 
 -- 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
@@ -252,14 +229,10 @@ currentServerSMPRelayVersion = VersionSMP 20
 proxiedSMPRelayVersion :: VersionSMP
 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
 
@@ -267,7 +240,7 @@ supportedProxyClientSMPRelayVRange :: VersionRangeSMP
 supportedProxyClientSMPRelayVRange = mkVersionRange minServerSMPRelayVersion currentServerSMPRelayVersion
 
 proxiedSMPRelayVRange :: VersionRangeSMP
-proxiedSMPRelayVRange = mkVersionRange sendingProxySMPVersion proxiedSMPRelayVersion
+proxiedSMPRelayVRange = mkVersionRange minServerSMPRelayVersion proxiedSMPRelayVersion
 
 alpnSupportedSMPHandshakes :: [ALPN]
 alpnSupportedSMPHandshakes = ["smp/1"]
@@ -489,14 +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
@@ -548,7 +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
@@ -602,14 +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}
 
@@ -632,22 +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
@@ -663,14 +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)
@@ -763,12 +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
@@ -800,35 +765,17 @@ 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) <$> (C.x509ToPublic' =<< C.verifyX509 serverKey exact)
       let v = maxVersion vr
           serviceVersion ServiceCredentials {serviceRole} = if serviceRole == SRMessaging then rcvServiceSMPVersion else serviceCertsSMPVersion
           serviceKeys = case serviceKeys_ of
@@ -838,7 +785,7 @@ smpClientHandshake c ks_ keyHash@(C.KeyHash kh) vRange proxyServer serviceKeys_
           hs = SMPClientHandshake {smpVersion = v, keyHash, authPubKey = fst <$> 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 <$> ks_) ck proxyServer service serverInfoBytes
     Nothing -> throwE TEVersion
   where
     th@THandle {params = THandleParams {sessionId}} = smpTHandle c
@@ -855,17 +802,17 @@ smpClientHandshake c ks_ keyHash@(C.KeyHash kh) vRange proxyServer serviceKeys_
 smpTHandleServer :: forall c. THandleSMP c 'TServer -> VersionSMP -> VersionRangeSMP -> C.PrivateKeyX25519 -> Maybe C.PublicKeyX25519 -> Bool -> Maybe THPeerClientService -> IO (THandleSMP c 'TServer)
 smpTHandleServer th v vr pk k_ proxyServer peerClientService = do
   let thAuth = Just THAuthServer {serverPrivKey = pk, peerClientService, sessSecret' = (`C.dh'` pk) <$!> 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 <$> be) serverInfoBytes
   where
-    clientTHParams (k, ck) =
+    clientTHParams =
       THAuthClient
         { peerServerPubKey = k,
           peerServerCertKey = forceCertChain ck,
@@ -873,9 +820,9 @@ smpTHandleClient th v vr pk_ ck_ proxyServer clientService = do
           sessSecret = C.dh' k <$!> 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
@@ -883,8 +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' =
@@ -892,9 +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'}
 
@@ -930,10 +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)

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)
@@ -380,7 +376,7 @@ testEncodeDecode x = do
 testX3dh :: forall a. (AlgorithmI a, DhAlgorithm a) => C.SAlgorithm a -> IO ()
 testX3dh _ = do
   g <- C.newRandom
-  let v = max pqRatchetE2EEncryptVersion currentE2EEncryptVersion
+  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
@@ -399,7 +395,7 @@ testX3dhV1 _ = do
 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)
   (pksAlice@(_, _, Nothing), e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOff
   -- propose KEM in reply
@@ -411,7 +407,7 @@ testPqX3dhProposeInReply _ = do
 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)
   (pksAlice@(_, _, Just _), e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOn
   E2ERatchetParams _ _ _ (Just (RKParamsProposed aliceKem)) <- pure e2eAlice
@@ -424,7 +420,7 @@ testPqX3dhProposeAccept _ = do
 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)
   (pksAlice@(_, _, Just _), e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOn
   E2ERatchetParams _ _ _ (Just (RKParamsProposed _)) <- pure e2eAlice
@@ -437,7 +433,7 @@ testPqX3dhProposeReject _ = do
 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)
   (pksAlice@(_, _, Nothing), e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOff
   E2ERatchetParams _ _ _ Nothing <- pure e2eAlice
@@ -451,7 +447,7 @@ testPqX3dhAcceptWithoutProposalError _ = do
 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)
   (pksAlice@(_, _, Just _), e2eAlice) <- liftIO $ generateRcvE2EParams @a g v PQSupportOn
   E2ERatchetParams _ _ _ (Just (RKParamsProposed _)) <- pure e2eAlice
@@ -514,7 +510,7 @@ 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
+  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
@@ -528,7 +524,7 @@ 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)
   (pksAlice@(_, pkAlice2, Nothing), e2eAlice) <- liftIO $ generateRcvE2EParams g v PQSupportOff
   -- propose KEM in reply
@@ -545,7 +541,7 @@ 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)
   (pksAlice@(_, pkAlice2, Just _), e2eAlice) <- liftIO $ generateRcvE2EParams g v PQSupportOn
   E2ERatchetParams _ _ _ (Just (RKParamsProposed aliceKem)) <- pure e2eAlice
@@ -563,7 +559,7 @@ 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)
   (pksAlice@(_, pkAlice2, Just _), e2eAlice) <- liftIO $ generateRcvE2EParams g v PQSupportOn
   -- propose KEM again in reply

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/SQLiteTests.hs

@@ -198,7 +198,8 @@ cData1 =
       lastExternalSndId = 0,
       deleted = False,
       ratchetSyncState = RSOk,
-      pqSupport = CR.PQSupportOn
+      pqSupport = CR.PQSupportOn,
+      serviceRequestExpiresAt = Nothing
     }
 
 testPrivateAuthKey :: C.APrivateAuthKey
@@ -696,7 +697,7 @@ testGetPendingServerCommand st = do
     Right (Just PendingCommand {corrId = corrId'}) <- getPendingServerCommand db connId (Just smpServer1)
     corrId' `shouldBe` "4"
   where
-    command = AClientCommand $ NEW True (ACM SCMInvitation) IKPQOn SMSubscribe
+    command = AClientCommand $ NEW True (ACM SCMInvitation) IKPQOn SMSubscribe False
     corruptCmd :: DB.Connection -> ByteString -> ConnId -> IO ()
     corruptCmd db corrId connId = DB.execute db "UPDATE commands SET command = cast('bad' as blob) WHERE conn_id = ? AND corr_id = ?" (connId, corrId)
 

tests/AgentTests/ShortLinkTests.hs

@@ -49,7 +49,7 @@ testInvShortLink = do
   Right srvData <- runExceptT $ SL.encryptLinkData g k linkData
   -- decrypt
   Right (FixedLinkData {linkConnReq = connReq}, connData') <- pure $ SL.decryptLinkData linkKey k srvData
-  connReq `shouldBe` invConnRequest
+  connReq `shouldBe` binaryConnReq invConnRequest
   linkUserData connData' `shouldBe` userData
 
 testInvShortLinkBadDataHash :: IO ()
@@ -80,14 +80,14 @@ testContactShortLink = do
   g <- C.newRandom
   sigKeys <- atomically $ C.generateKeyPair @'C.Ed25519 g
   let userData = UserLinkData "some user data"
-      userCtData = UserContactData {direct = True, owners = [], relays = [], userData}
+      userCtData = UserContactData {direct = True, owners = [], relays = [], userData, ratchetKeys = Nothing}
       userLinkData = UserContactLinkData userCtData
       (linkKey, linkData) = SL.encodeSignLinkData sigKeys supportedSMPAgentVRange contactConnRequest Nothing userLinkData
       (_linkId, k) = SL.contactShortLinkKdf linkKey
   Right srvData <- runExceptT $ SL.encryptLinkData g k linkData
   -- decrypt
   Right (FixedLinkData {linkConnReq = connReq}, ContactLinkData _ userCtData') <- pure $ SL.decryptLinkData @'CMContact linkKey k srvData
-  connReq `shouldBe` contactConnRequest
+  connReq `shouldBe` binaryConnReq contactConnRequest
   userCtData' `shouldBe` userCtData
 
 testUpdateContactShortLink :: IO ()
@@ -96,20 +96,20 @@ testUpdateContactShortLink = do
   g <- C.newRandom
   sigKeys <- atomically $ C.generateKeyPair @'C.Ed25519 g
   let userData = UserLinkData "some user data"
-      userCtData = UserContactData {direct = True, owners = [], relays = [], userData}
+      userCtData = UserContactData {direct = True, owners = [], relays = [], userData, ratchetKeys = Nothing}
       userLinkData = UserContactLinkData userCtData
       (linkKey, linkData) = SL.encodeSignLinkData sigKeys supportedSMPAgentVRange contactConnRequest Nothing userLinkData
       (_linkId, k) = SL.contactShortLinkKdf linkKey
   Right (fd, _ud) <- runExceptT $ SL.encryptLinkData g k linkData
   -- encrypt updated user data
   let updatedUserData = UserLinkData "updated user data"
-      userCtData' = UserContactData {direct = False, owners = [], relays = [relayLink1, relayLink2], userData = updatedUserData}
+      userCtData' = UserContactData {direct = False, owners = [], relays = [relayLink1, relayLink2], userData = updatedUserData, ratchetKeys = Nothing}
       userLinkData' = UserContactLinkData userCtData'
       signed = SL.encodeSignUserData SCMContact (snd sigKeys) supportedSMPAgentVRange userLinkData'
   Right ud' <- runExceptT $ SL.encryptUserData g k signed
   -- decrypt
   Right (FixedLinkData {linkConnReq = connReq}, ContactLinkData _ userCtData'') <- pure $ SL.decryptLinkData @'CMContact linkKey k (fd, ud')
-  connReq `shouldBe` contactConnRequest
+  connReq `shouldBe` binaryConnReq contactConnRequest
   userCtData'' `shouldBe` userCtData'
 
 testContactShortLinkBadDataHash :: IO ()
@@ -118,7 +118,7 @@ testContactShortLinkBadDataHash = do
   g <- C.newRandom
   sigKeys <- atomically $ C.generateKeyPair @'C.Ed25519 g
   let userData = UserLinkData "some user data"
-      userLinkData = UserContactLinkData UserContactData {direct = True, owners = [], relays = [], userData}
+      userLinkData = UserContactLinkData UserContactData {direct = True, owners = [], relays = [], userData, ratchetKeys = Nothing}
       (_linkKey, linkData) = SL.encodeSignLinkData sigKeys supportedSMPAgentVRange contactConnRequest Nothing userLinkData
   -- different key
   linkKey <- LinkKey <$> atomically (C.randomBytes 32 g)
@@ -134,13 +134,13 @@ testContactShortLinkBadSignature = do
   g <- C.newRandom
   sigKeys <- atomically $ C.generateKeyPair @'C.Ed25519 g
   let userData = UserLinkData "some user data"
-      userLinkData = UserContactLinkData UserContactData {direct = True, owners = [], relays = [], userData}
+      userLinkData = UserContactLinkData UserContactData {direct = True, owners = [], relays = [], userData, ratchetKeys = Nothing}
       (linkKey, linkData) = SL.encodeSignLinkData sigKeys supportedSMPAgentVRange contactConnRequest Nothing userLinkData
       (_linkId, k) = SL.contactShortLinkKdf linkKey
   Right (fd, _ud) <- runExceptT $ SL.encryptLinkData g k linkData
   -- encrypt updated user data
   let updatedUserData = UserLinkData "updated user data"
-      userLinkData' = UserContactLinkData UserContactData {direct = True, owners = [], relays = [], userData = updatedUserData}
+      userLinkData' = UserContactLinkData UserContactData {direct = True, owners = [], relays = [], userData = updatedUserData, ratchetKeys = Nothing}
   -- another signature key
   (_, pk) <- atomically $ C.generateKeyPair @'C.Ed25519 g
   let signed = SL.encodeSignUserData SCMContact pk supportedSMPAgentVRange userLinkData'
@@ -156,7 +156,7 @@ testContactShortLinkOwner = do
   (pk, lnk) <- encryptLink g
   -- encrypt updated user data
   (ownerPK, owner) <- authNewOwner g pk
-  let ud = UserContactData {direct = True, owners = [owner], relays = [], userData = UserLinkData "updated user data"}
+  let ud = UserContactData {direct = True, owners = [owner], relays = [], userData = UserLinkData "updated user data", ratchetKeys = Nothing}
   testEncDec g pk lnk ud
   testEncDec g ownerPK lnk ud
   (_, wrongKey) <- atomically $ C.generateKeyPair @'C.Ed25519 g
@@ -166,7 +166,7 @@ encryptLink :: TVar ChaChaDRG -> IO (C.PrivateKeyEd25519, (EncFixedDataBytes, Li
 encryptLink g = do
   sigKeys@(_, pk) <- atomically $ C.generateKeyPair @'C.Ed25519 g
   let userData = UserLinkData "some user data"
-      userLinkData = UserContactLinkData UserContactData {direct = True, owners = [], relays = [], userData}
+      userLinkData = UserContactLinkData UserContactData {direct = True, owners = [], relays = [], userData, ratchetKeys = Nothing}
       (linkKey, linkData) = SL.encodeSignLinkData sigKeys supportedSMPAgentVRange contactConnRequest Nothing userLinkData
       (_linkId, k) = SL.contactShortLinkKdf linkKey
   Right (fd, _ud) <- runExceptT $ SL.encryptLinkData g k linkData
@@ -184,7 +184,7 @@ testEncDec g pk (fd, linkKey, k) ctData = do
   let signed = SL.encodeSignUserData SCMContact pk supportedSMPAgentVRange $ UserContactLinkData ctData
   Right ud <- runExceptT $ SL.encryptUserData g k signed
   Right (FixedLinkData {linkConnReq = connReq'}, ContactLinkData _ ctData') <- pure $ SL.decryptLinkData @'CMContact linkKey k (fd, ud)
-  connReq' `shouldBe` contactConnRequest
+  connReq' `shouldBe` binaryConnReq contactConnRequest
   ctData' `shouldBe` ctData
 
 testContactShortLinkManyOwners :: IO ()
@@ -199,7 +199,7 @@ testContactShortLinkManyOwners = do
   (ownerPK4, owner4) <- authNewOwner g ownerPK1
   (ownerPK5, owner5) <- authNewOwner g ownerPK3
   let owners = [owner1, owner2, owner3, owner4, owner5]
-      ud = UserContactData {direct = True, owners, relays = [], userData = UserLinkData "updated user data"}
+      ud = UserContactData {direct = True, owners, relays = [], userData = UserLinkData "updated user data", ratchetKeys = Nothing}
   testEncDec g pk lnk ud
   testEncDec g ownerPK1 lnk ud
   testEncDec g ownerPK2 lnk ud
@@ -216,7 +216,7 @@ testContactShortLinkInvalidOwners = do
   (pk, lnk) <- encryptLink g
   -- encrypt updated user data
   (ownerPK, owner) <- authNewOwner g pk
-  let mkCtData owners = UserContactData {direct = True, owners, relays = [], userData = UserLinkData "updated user data"}
+  let mkCtData owners = UserContactData {direct = True, owners, relays = [], userData = UserLinkData "updated user data", ratchetKeys = Nothing}
   -- decryption fails: owner uses root key
   let ud = mkCtData [owner {ownerKey = C.publicKey pk}]
       err = A_LINK $ "owner key for ID " <> ownerIdStr owner <> " matches root key"

tests/CoreTests/BatchingTests.hs

@@ -30,148 +30,60 @@ import Util
 batchingTests :: Spec
 batchingTests = do
   describe "batchTransmissions" $ do
-    describe "SMP v6 (previous)" $ do
-      it "should batch with 106 subscriptions per batch" testBatchSubscriptionsV6
-      it "should break on message that does not fit" testBatchWithMessageV6
-      it "should break on large message" testBatchWithLargeMessageV6
-    describe "SMP current" $ do
-      it "should batch with 135 subscriptions per batch" testBatchSubscriptions
-      it "should break on message that does not fit" testBatchWithMessage
-      it "should break on large message" testBatchWithLargeMessage
+    it "should batch with 135 subscriptions per batch" testBatchSubscriptions
+    it "should break on message that does not fit" testBatchWithMessage
+    it "should break on large message" testBatchWithLargeMessage
   describe "batchTransmissions'" $ do
-    describe "SMP v6 (previous)" $ do
-      it "should batch with 106 subscriptions per batch" testClientBatchSubscriptionsV6
-      it "should break on message that does not fit" testClientBatchWithMessageV6
-      it "should break on large message" testClientBatchWithLargeMessageV6
-    describe "SMP current" $ do
-      it "should batch with 135 subscriptions per batch" testClientBatchSubscriptions
-      it "should batch with 255 ENDs per batch" testClientBatchENDs
-      it "should batch with 80 NMSGs per batch" testClientBatchNMSGs
-      it "should batch subscription responses with message" testBatchSubResponses
-      it "should break on message that does not fit" testClientBatchWithMessage
-      it "should break on large message" testClientBatchWithLargeMessage
-
-testBatchSubscriptionsV6 :: IO ()
-testBatchSubscriptionsV6 = do
-  sessId <- atomically . C.randomBytes 32 =<< C.newRandom
-  subs <- replicateM 250 $ randomSUBv6 sessId
-  let thParams = testTHandleParams minServerSMPRelayVersion sessId
-      batches1 = batchTransmissions thParams {batch = False} $ L.fromList subs
-  all lenOk1 batches1 `shouldBe` True
-  length batches1 `shouldBe` 250
-  let batches = batchTransmissions thParams $ L.fromList subs
-  length batches `shouldBe` 3
-  [TBTransmissions s1 n1 _, TBTransmissions s2 n2 _, TBTransmissions s3 n3 _] <- pure batches
-  (n1, n2, n3) `shouldBe` (38, 106, 106)
-  all lenOk [s1, s2, s3] `shouldBe` True
+    it "should batch with 135 subscriptions per batch" testClientBatchSubscriptions
+    it "should batch with 255 ENDs per batch" testClientBatchENDs
+    it "should batch with 80 NMSGs per batch" testClientBatchNMSGs
+    it "should batch subscription responses with message" testBatchSubResponses
+    it "should break on message that does not fit" testClientBatchWithMessage
+    it "should break on large message" testClientBatchWithLargeMessage
 
 testBatchSubscriptions :: IO ()
 testBatchSubscriptions = do
   sessId <- atomically . C.randomBytes 32 =<< C.newRandom
   subs <- replicateM 300 $ randomSUB sessId
-  let thParams = testTHandleParams currentClientSMPRelayVersion sessId
-      batches1 = batchTransmissions thParams {batch = False} $ L.fromList subs
-  all lenOk1 batches1 `shouldBe` True
-  length batches1 `shouldBe` 300
+  let thParams = testTHandleParams sessId
   let batches = batchTransmissions thParams $ L.fromList subs
   length batches `shouldBe` 3
   [TBTransmissions s1 n1 _, TBTransmissions s2 n2 _, TBTransmissions s3 n3 _] <- pure batches
   (n1, n2, n3) `shouldBe` (30, 135, 135)
   all lenOk [s1, s2, s3] `shouldBe` True
 
-testBatchWithMessageV6 :: IO ()
-testBatchWithMessageV6 = do
-  sessId <- atomically . C.randomBytes 32 =<< C.newRandom
-  subs1 <- replicateM 60 $ randomSUBv6 sessId
-  send <- randomSENDv6 sessId 8000
-  subs2 <- replicateM 40 $ randomSUBv6 sessId
-  let thParams = testTHandleParams minServerSMPRelayVersion sessId
-      cmds = subs1 <> [send] <> subs2
-      batches1 = batchTransmissions thParams {batch = False} $ L.fromList cmds
-  all lenOk1 batches1 `shouldBe` True
-  length batches1 `shouldBe` 101
-  let batches = batchTransmissions thParams $ L.fromList cmds
-  length batches `shouldBe` 2
-  [TBTransmissions s1 n1 _, TBTransmissions s2 n2 _] <- pure batches
-  (n1, n2) `shouldBe` (47, 54)
-  all lenOk [s1, s2] `shouldBe` True
-
 testBatchWithMessage :: IO ()
 testBatchWithMessage = do
   sessId <- atomically . C.randomBytes 32 =<< C.newRandom
   subs1 <- replicateM 60 $ randomSUB sessId
   send <- randomSEND sessId 8000
   subs2 <- replicateM 40 $ randomSUB sessId
-  let thParams = testTHandleParams currentClientSMPRelayVersion sessId
+  let thParams = testTHandleParams sessId
       cmds = subs1 <> [send] <> subs2
-      batches1 = batchTransmissions thParams {batch = False} $ L.fromList cmds
-  all lenOk1 batches1 `shouldBe` True
-  length batches1 `shouldBe` 101
   let batches = batchTransmissions thParams $ L.fromList cmds
   length batches `shouldBe` 2
   [TBTransmissions s1 n1 _, TBTransmissions s2 n2 _] <- pure batches
   (n1, n2) `shouldBe` (33, 68)
   all lenOk [s1, s2] `shouldBe` True
 
-testBatchWithLargeMessageV6 :: IO ()
-testBatchWithLargeMessageV6 = do
-  sessId <- atomically . C.randomBytes 32 =<< C.newRandom
-  subs1 <- replicateM 50 $ randomSUBv6 sessId
-  send <- randomSENDv6 sessId 17000
-  subs2 <- replicateM 150 $ randomSUBv6 sessId
-  let thParams = testTHandleParams minServerSMPRelayVersion sessId
-      cmds = subs1 <> [send] <> subs2
-      batches1 = batchTransmissions thParams {batch = False} $ L.fromList cmds
-  all lenOk1 batches1 `shouldBe` False
-  length batches1 `shouldBe` 201
-  let batches1' = take 50 batches1 <> drop 51 batches1
-  all lenOk1 batches1' `shouldBe` True
-  length batches1' `shouldBe` 200
-  let batches = batchTransmissions thParams $ L.fromList cmds
-  length batches `shouldBe` 4
-  [TBTransmissions s1 n1 _, TBError TELargeMsg _, TBTransmissions s2 n2 _, TBTransmissions s3 n3 _] <- pure batches
-  (n1, n2, n3) `shouldBe` (50, 44, 106)
-  all lenOk [s1, s2, s3] `shouldBe` True
-
 testBatchWithLargeMessage :: IO ()
 testBatchWithLargeMessage = do
   sessId <- atomically . C.randomBytes 32 =<< C.newRandom
   subs1 <- replicateM 60 $ randomSUB sessId
   send <- randomSEND sessId 17000
   subs2 <- replicateM 150 $ randomSUB sessId
-  let thParams = testTHandleParams currentClientSMPRelayVersion sessId
+  let thParams = testTHandleParams sessId
       cmds = subs1 <> [send] <> subs2
-      batches1 = batchTransmissions thParams {batch = False} $ L.fromList cmds
-  all lenOk1 batches1 `shouldBe` False
-  length batches1 `shouldBe` 211
-  let batches1' = take 60 batches1 <> drop 61 batches1
-  all lenOk1 batches1' `shouldBe` True
-  length batches1' `shouldBe` 210
   let batches = batchTransmissions thParams $ L.fromList cmds
   length batches `shouldBe` 4
   [TBTransmissions s1 n1 _, TBError TELargeMsg _, TBTransmissions s2 n2 _, TBTransmissions s3 n3 _] <- pure batches
   (n1, n2, n3) `shouldBe` (60, 15, 135)
   all lenOk [s1, s2, s3] `shouldBe` True
 
-testClientBatchSubscriptionsV6 :: IO ()
-testClientBatchSubscriptionsV6 = do
-  client <- testClientStubV6
-  subs <- replicateM 250 $ randomSUBCmdV6 client
-  let batches1 = batchTransmissions' (thParams client) {batch = False} $ L.fromList subs
-  all lenOk1 batches1 `shouldBe` True
-  let batches = batchTransmissions' (thParams client) $ L.fromList subs
-  length batches `shouldBe` 3
-  [TBTransmissions s1 n1 rs1, TBTransmissions s2 n2 rs2, TBTransmissions s3 n3 rs3] <- pure batches
-  (n1, n2, n3) `shouldBe` (38, 106, 106)
-  (length rs1, length rs2, length rs3) `shouldBe` (38, 106, 106)
-  all lenOk [s1, s2, s3] `shouldBe` True
-
 testClientBatchSubscriptions :: IO ()
 testClientBatchSubscriptions = do
   client <- testClientStub
   subs <- replicateM 300 $ randomSUBCmd client
-  let batches1 = batchTransmissions' (thParams client) {batch = False} $ L.fromList subs
-  all lenOk1 batches1 `shouldBe` True
   let batches = batchTransmissions' (thParams client) $ L.fromList subs
   length batches `shouldBe` 3
   [TBTransmissions s1 n1 rs1, TBTransmissions s2 n2 rs2, TBTransmissions s3 n3 rs3] <- pure batches
@@ -184,8 +96,6 @@ testClientBatchENDs = do
   client <- testClientStub
   ends <- replicateM 300 randomENDCmd
   let ends' = map (\t -> Right (Nothing, encodeTransmission (thParams client) t)) ends
-      batches1 = batchTransmissions (thParams client) {batch = False} $ L.fromList ends'
-  all lenOk1 batches1 `shouldBe` True
   let batches = batchTransmissions (thParams client) $ L.fromList ends'
   length batches `shouldBe` 2
   [TBTransmissions s1 n1 rs1, TBTransmissions s2 n2 rs2] <- pure batches
@@ -199,8 +109,6 @@ testClientBatchNMSGs = do
   ts <- getSystemTime
   ntfs <- replicateM 200 $ randomNMSGCmd ts
   let ntfs' = map (\t -> Right (Nothing, encodeTransmission (thParams client) t)) ntfs
-      batches1 = batchTransmissions (thParams client) {batch = False} $ L.fromList ntfs'
-  all lenOk1 batches1 `shouldBe` True
   let batches = batchTransmissions (thParams client) $ L.fromList ntfs'
   length batches `shouldBe` 3
   [TBTransmissions s1 n1 rs1, TBTransmissions s2 n2 rs2, TBTransmissions s3 n3 rs3] <- pure batches
@@ -222,23 +130,6 @@ testBatchSubResponses = do
       batches' = batchTransmissions (thParams client) $ L.fromList msgs'
   length batches' `shouldBe` 2
 
-testClientBatchWithMessageV6 :: IO ()
-testClientBatchWithMessageV6 = do
-  client <- testClientStubV6
-  subs1 <- replicateM 60 $ randomSUBCmdV6 client
-  send <- randomSENDCmdV6 client 8000
-  subs2 <- replicateM 40 $ randomSUBCmdV6 client
-  let cmds = subs1 <> [send] <> subs2
-      batches1 = batchTransmissions' (thParams client) {batch = False} $ L.fromList cmds
-  all lenOk1 batches1 `shouldBe` True
-  length batches1 `shouldBe` 101
-  let batches = batchTransmissions' (thParams client) $ L.fromList cmds
-  length batches `shouldBe` 2
-  [TBTransmissions s1 n1 rs1, TBTransmissions s2 n2 rs2] <- pure batches
-  (n1, n2) `shouldBe` (47, 54)
-  (length rs1, length rs2) `shouldBe` (47, 54)
-  all lenOk [s1, s2] `shouldBe` True
-
 testClientBatchWithMessage :: IO ()
 testClientBatchWithMessage = do
   client <- testClientStub
@@ -246,45 +137,13 @@ testClientBatchWithMessage = do
   send <- randomSENDCmd client 8000
   subs2 <- replicateM 40 $ randomSUBCmd client
   let cmds = subs1 <> [send] <> subs2
-      batches1 = batchTransmissions' (thParams client) {batch = False} $ L.fromList cmds
-  all lenOk1 batches1 `shouldBe` True
-  length batches1 `shouldBe` 101
-  let batches = batchTransmissions' (thParams client) $ L.fromList cmds
+      batches = batchTransmissions' (thParams client) $ L.fromList cmds
   length batches `shouldBe` 2
   [TBTransmissions s1 n1 rs1, TBTransmissions s2 n2 rs2] <- pure batches
   (n1, n2) `shouldBe` (33, 68)
   (length rs1, length rs2) `shouldBe` (33, 68)
   all lenOk [s1, s2] `shouldBe` True
 
-testClientBatchWithLargeMessageV6 :: IO ()
-testClientBatchWithLargeMessageV6 = do
-  client <- testClientStubV6
-  subs1 <- replicateM 50 $ randomSUBCmdV6 client
-  send <- randomSENDCmdV6 client 17000
-  subs2 <- replicateM 150 $ randomSUBCmdV6 client
-  let cmds = subs1 <> [send] <> subs2
-      batches1 = batchTransmissions' (thParams client) {batch = False} $ L.fromList cmds
-  all lenOk1 batches1 `shouldBe` False
-  length batches1 `shouldBe` 201
-  let batches1' = take 50 batches1 <> drop 51 batches1
-  all lenOk1 batches1' `shouldBe` True
-  length batches1' `shouldBe` 200
-  --
-  let batches = batchTransmissions' (thParams client) $ L.fromList cmds
-  length batches `shouldBe` 4
-  [TBTransmissions s1 n1 rs1, TBError TELargeMsg _, TBTransmissions s2 n2 rs2, TBTransmissions s3 n3 rs3] <- pure batches
-  (n1, n2, n3) `shouldBe` (50, 44, 106)
-  (length rs1, length rs2, length rs3) `shouldBe` (50, 44, 106)
-  all lenOk [s1, s2, s3] `shouldBe` True
-  --
-  let cmds' = [send] <> subs1 <> subs2
-  let batches' = batchTransmissions' (thParams client) $ L.fromList cmds'
-  length batches' `shouldBe` 3
-  [TBError TELargeMsg _, TBTransmissions s1' n1' rs1', TBTransmissions s2' n2' rs2'] <- pure batches'
-  (n1', n2') `shouldBe` (94, 106)
-  (length rs1', length rs2') `shouldBe` (94, 106)
-  all lenOk [s1', s2'] `shouldBe` True
-
 testClientBatchWithLargeMessage :: IO ()
 testClientBatchWithLargeMessage = do
   client <- testClientStub
@@ -292,14 +151,7 @@ testClientBatchWithLargeMessage = do
   send <- randomSENDCmd client 17000
   subs2 <- replicateM 150 $ randomSUBCmd client
   let cmds = subs1 <> [send] <> subs2
-      batches1 = batchTransmissions' (thParams client) {batch = False} $ L.fromList cmds
-  all lenOk1 batches1 `shouldBe` False
-  length batches1 `shouldBe` 211
-  let batches1' = take 60 batches1 <> drop 61 batches1
-  all lenOk1 batches1' `shouldBe` True
-  length batches1' `shouldBe` 210
-  --
-  let batches = batchTransmissions' (thParams client) $ L.fromList cmds
+      batches = batchTransmissions' (thParams client) $ L.fromList cmds
   length batches `shouldBe` 4
   [TBTransmissions s1 n1 rs1, TBError TELargeMsg _, TBTransmissions s2 n2 rs2, TBTransmissions s3 n3 rs3] <- pure batches
   (n1, n2, n3) `shouldBe` (60, 15, 135)
@@ -314,49 +166,30 @@ testClientBatchWithLargeMessage = do
   (length rs1', length rs2') `shouldBe` (75, 135)
   all lenOk [s1', s2'] `shouldBe` True
 
-testClientStubV6 :: IO (ProtocolClient SMPVersion ErrorType BrokerMsg)
-testClientStubV6 = do
-  g <- C.newRandom
-  sessId <- atomically $ C.randomBytes 32 g
-  smpClientStub g sessId minServerSMPRelayVersion Nothing
-
 testClientStub :: IO (ProtocolClient SMPVersion ErrorType BrokerMsg)
 testClientStub = do
   g <- C.newRandom
   sessId <- atomically $ C.randomBytes 32 g
   (rKey, _) <- atomically $ C.generateAuthKeyPair C.SX25519 g
-  thAuth_ <- testTHandleAuth currentClientSMPRelayVersion g rKey
+  thAuth_ <- testTHandleAuth g rKey
   smpClientStub g sessId currentClientSMPRelayVersion thAuth_
 
-randomSUBv6 :: ByteString -> IO (Either TransportError (Maybe TAuthorizations, ByteString))
-randomSUBv6 = randomSUB_ C.SEd25519 minServerSMPRelayVersion
-
 randomSUB :: ByteString -> IO (Either TransportError (Maybe TAuthorizations, ByteString))
-randomSUB = randomSUB_ C.SEd25519 currentClientSMPRelayVersion
-
--- TODO [certs rcv] test with the additional certificate signature
-randomSUB_ :: (C.AlgorithmI a, C.AuthAlgorithm a) => C.SAlgorithm a -> VersionSMP -> ByteString -> IO (Either TransportError (Maybe TAuthorizations, ByteString))
-randomSUB_ a v sessId = do
+randomSUB sessId = do
   g <- C.newRandom
   rId <- atomically $ C.randomBytes 24 g
   nonce@(C.CbNonce corrId) <- atomically $ C.randomCbNonce g
-  (rKey, rpKey) <- atomically $ C.generateAuthKeyPair a g
-  thAuth_ <- testTHandleAuth v g rKey
-  let thParams = testTHandleParams v sessId
+  (rKey, rpKey) <- atomically $ C.generateAuthKeyPair C.SEd25519 g
+  thAuth_ <- testTHandleAuth g rKey
+  let thParams = testTHandleParams sessId
       TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth thParams (CorrId corrId, EntityId rId, Cmd SRecipient SUB)
   pure $ (,tToSend) <$> authTransmission thAuth_ True (Just rpKey) nonce tForAuth
 
-randomSUBCmdV6 :: ProtocolClient SMPVersion ErrorType BrokerMsg -> IO (PCTransmission ErrorType BrokerMsg)
-randomSUBCmdV6 = randomSUBCmd_ C.SEd25519
-
 randomSUBCmd :: ProtocolClient SMPVersion ErrorType BrokerMsg -> IO (PCTransmission ErrorType BrokerMsg)
-randomSUBCmd = randomSUBCmd_ C.SEd25519 -- same as v6
-
-randomSUBCmd_ :: (C.AlgorithmI a, C.AuthAlgorithm a) => C.SAlgorithm a -> ProtocolClient SMPVersion ErrorType BrokerMsg -> IO (PCTransmission ErrorType BrokerMsg)
-randomSUBCmd_ a c = do
+randomSUBCmd c = do
   g <- C.newRandom
   rId <- atomically $ C.randomBytes 24 g
-  (_, rpKey) <- atomically $ C.generateAuthKeyPair a g
+  (_, rpKey) <- atomically $ C.generateAuthKeyPair C.SEd25519 g
   mkTransmission c (EntityId rId, Just rpKey, Cmd SRecipient SUB)
 
 randomENDCmd :: IO (Transmission BrokerMsg)
@@ -389,44 +222,38 @@ randomMSG = do
   corrId <- atomically $ C.randomBytes 24 g
   rId <- atomically $ C.randomBytes 24 g
   msgId <- atomically $ C.randomBytes 24 g
-  msg <- atomically $ C.randomBytes (maxMessageLength currentClientSMPRelayVersion) g
+  msg <- atomically $ C.randomBytes maxMessageLength g
   pure (CorrId corrId, EntityId rId, MSG RcvMessage {msgId, msgBody = EncRcvMsgBody msg})
 
-randomSENDv6 :: ByteString -> Int -> IO (Either TransportError (Maybe TAuthorizations, ByteString))
-randomSENDv6 = randomSEND_ C.SEd25519 minServerSMPRelayVersion
-
 randomSEND :: ByteString -> Int -> IO (Either TransportError (Maybe TAuthorizations, ByteString))
-randomSEND = randomSEND_ C.SX25519 currentClientSMPRelayVersion
-
-randomSEND_ :: (C.AlgorithmI a, C.AuthAlgorithm a) => C.SAlgorithm a -> VersionSMP -> ByteString -> Int -> IO (Either TransportError (Maybe TAuthorizations, ByteString))
-randomSEND_ a v sessId len = do
+randomSEND sessId len = do
   g <- C.newRandom
   sId <- atomically $ C.randomBytes 24 g
   nonce@(C.CbNonce corrId) <- atomically $ C.randomCbNonce g
-  (sKey, spKey) <- atomically $ C.generateAuthKeyPair a g
-  thAuth_ <- testTHandleAuth v g sKey
+  (sKey, spKey) <- atomically $ C.generateAuthKeyPair C.SX25519 g
+  thAuth_ <- testTHandleAuth g sKey
   msg <- atomically $ C.randomBytes len g
-  let thParams = testTHandleParams v sessId
+  let thParams = testTHandleParams sessId
       TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth thParams (CorrId corrId, EntityId sId, Cmd SSender $ SEND noMsgFlags msg)
   pure $ (,tToSend) <$> authTransmission thAuth_ False (Just spKey) nonce tForAuth
 
-testTHandleParams :: VersionSMP -> ByteString -> THandleParams SMPVersion 'TClient
-testTHandleParams v sessionId =
+testTHandleParams :: ByteString -> THandleParams SMPVersion 'TClient
+testTHandleParams sessionId =
   THandleParams
     { sessionId,
       blockSize = smpBlockSize,
-      thVersion = v,
+      thVersion = currentClientSMPRelayVersion,
       thServerVRange = supportedServerSMPRelayVRange,
       thAuth = Nothing,
-      implySessId = v >= authCmdsSMPVersion,
+      implySessId = True,
       encryptBlock = Nothing,
-      batch = True,
-      serviceAuth = v >= serviceCertsSMPVersion
+      serviceAuth = True,
+      serverInfo = Nothing
     }
 
-testTHandleAuth :: VersionSMP -> TVar ChaChaDRG -> C.APublicAuthKey -> IO (Maybe (THandleAuth 'TClient))
-testTHandleAuth v g (C.APublicAuthKey a peerServerPubKey) = case a of
-  C.SX25519 | v >= authCmdsSMPVersion -> do
+testTHandleAuth :: TVar ChaChaDRG -> C.APublicAuthKey -> IO (Maybe (THandleAuth 'TClient))
+testTHandleAuth g (C.APublicAuthKey a peerServerPubKey) = case a of
+  C.SX25519 -> do
     ca <- head <$> XS.readCertificates "tests/fixtures/ca.crt"
     serverCert <- head <$> XS.readCertificates "tests/fixtures/server.crt"
     serverKey <- head <$> XF.readKeyFile "tests/fixtures/server.key"
@@ -436,24 +263,13 @@ testTHandleAuth v g (C.APublicAuthKey a peerServerPubKey) = case a of
     pure $ Just THAuthClient {peerServerPubKey, peerServerCertKey, clientService = Nothing, sessSecret = Nothing}
   _ -> pure Nothing
 
-randomSENDCmdV6 :: ProtocolClient SMPVersion ErrorType BrokerMsg -> Int -> IO (PCTransmission ErrorType BrokerMsg)
-randomSENDCmdV6 = randomSENDCmd_ C.SEd25519
-
 randomSENDCmd :: ProtocolClient SMPVersion ErrorType BrokerMsg -> Int -> IO (PCTransmission ErrorType BrokerMsg)
-randomSENDCmd = randomSENDCmd_ C.SX25519
-
-randomSENDCmd_ :: (C.AlgorithmI a, C.AuthAlgorithm a) => C.SAlgorithm a -> ProtocolClient SMPVersion ErrorType BrokerMsg -> Int -> IO (PCTransmission ErrorType BrokerMsg)
-randomSENDCmd_ a c len = do
+randomSENDCmd c len = do
   g <- C.newRandom
   sId <- atomically $ C.randomBytes 24 g
-  (_, rpKey) <- atomically $ C.generateAuthKeyPair a g
+  (_, rpKey) <- atomically $ C.generateAuthKeyPair C.SX25519 g
   msg <- atomically $ C.randomBytes len g
   mkTransmission c (EntityId sId, Just rpKey, Cmd SSender $ SEND noMsgFlags msg)
 
 lenOk :: ByteString -> Bool
 lenOk s = 0 < B.length s && B.length s <= smpBlockSize - 2
-
-lenOk1 :: TransportBatch r -> Bool
-lenOk1 = \case
-  TBTransmission s _ -> lenOk s
-  _ -> False

tests/NtfClient.hs

@@ -160,16 +160,16 @@ ntfServerCfg =
       startOptions = defaultStartOptions
     }
 
-ntfServerCfgVPrev :: NtfServerConfig
-ntfServerCfgVPrev =
-  ntfServerCfg
-    { ntfServerVRange = prevRange $ ntfServerVRange ntfServerCfg,
-      smpAgentCfg = smpAgentCfg' {smpCfg = smpCfg' {serverVRange = prevRange serverVRange'}}
-    }
-  where
-    smpAgentCfg' = smpAgentCfg ntfServerCfg
-    smpCfg' = smpCfg smpAgentCfg'
-    serverVRange' = serverVRange smpCfg'
+-- ntfServerCfgVPrev :: NtfServerConfig
+-- ntfServerCfgVPrev =
+--   ntfServerCfg
+--     { ntfServerVRange = prevRange $ ntfServerVRange ntfServerCfg,
+--       smpAgentCfg = smpAgentCfg' {smpCfg = smpCfg' {serverVRange = prevRange serverVRange'}}
+--     }
+--   where
+--     smpAgentCfg' = smpAgentCfg ntfServerCfg
+--     smpCfg' = smpCfg smpAgentCfg'
+--     serverVRange' = serverVRange smpCfg'
 
 withNtfServerThreadOn :: HasCallStack => ASrvTransport -> ServiceName -> PostgresStoreCfg -> (HasCallStack => ThreadId -> IO a) -> IO a
 withNtfServerThreadOn t port' dbStoreConfig =

tests/SMPAgentClient.hs

@@ -15,7 +15,7 @@ import Data.List.NonEmpty (NonEmpty)
 import qualified Data.List.NonEmpty as L
 import Data.Map.Strict (Map)
 import qualified Data.Map.Strict as M
-import SMPClient (proxyVRangeV8, ntfTestPort, testPort)
+import SMPClient (ntfTestPort, testPort)
 import Simplex.Messaging.Agent.Env.SQLite
 import Simplex.Messaging.Agent.Protocol
 import Simplex.Messaging.Agent.RetryInterval
@@ -103,9 +103,6 @@ agentCfg =
   where
     networkConfig = defaultNetworkConfig {tcpConnectTimeout = NetworkTimeout 1_000000 1_000000, tcpTimeout = NetworkTimeout 2_000000 2_000000}
 
-agentProxyCfgV8 :: AgentConfig
-agentProxyCfgV8 = agentCfg {smpCfg = (smpCfg agentCfg) {serverVRange = proxyVRangeV8}}
-
 fastRetryInterval :: RetryInterval
 fastRetryInterval = defaultReconnectInterval {initialInterval = 50_000}
 

tests/SMPClient.hs

@@ -179,9 +179,7 @@ testSMPClient_ host port vr serviceCreds_ client = do
       Right th -> client th
       Left e -> error $ show e
   where
-    clientALPN
-      | authCmdsSMPVersion `isCompatible` vr = Just alpnSupportedSMPHandshakes
-      | otherwise = Nothing
+    clientALPN = Just alpnSupportedSMPHandshakes
 
 runSMPClient :: Transport c => TProxy c 'TServer -> (THandleSMP c 'TClient -> IO a) -> IO a
 runSMPClient _ test' = testSMPClient test'
@@ -309,9 +307,6 @@ serverStoreConfig_ useDbStoreLog = \case
     dbStoreLogPath = if useDbStoreLog then Just testStoreLogFile else Nothing
     storeCfg = PostgresStoreCfg {dbOpts = testStoreDBOpts, dbStoreLogPath, confirmMigrations = MCYesUp, deletedTTL = 86400}
 
-cfgV7 :: AServerConfig
-cfgV7 = updateCfg cfg $ \cfg' -> cfg' {smpServerVRange = mkVersionRange minServerSMPRelayVersion authCmdsSMPVersion}
-
 cfgVPrev :: AStoreType -> AServerConfig
 cfgVPrev msType = updateCfg (cfgMS msType) $ \cfg' -> cfg' {smpServerVRange = prevRange $ smpServerVRange cfg'}
 
@@ -351,9 +346,6 @@ proxyCfgShortTimeout =
         nt = NetworkTimeout {backgroundTimeout = 4_000000, interactiveTimeout = 4_000000}
      in cfg' {smpAgentCfg = aCfg {smpCfg = cCfg {networkConfig = (networkConfig cCfg) {tcpConnectTimeout = nt}}}}
 
-proxyVRangeV8 :: VersionRangeSMP
-proxyVRangeV8 = mkVersionRange minServerSMPRelayVersion sendingProxySMPVersion
-
 withSmpServerStoreMsgLogOn :: HasCallStack => (ASrvTransport, AStoreType) -> ServiceName -> (HasCallStack => ThreadId -> IO a) -> IO a
 withSmpServerStoreMsgLogOn (t, msType) =
   withSmpServerConfigOn t $ updateCfg (cfgMS msType) $ \cfg' -> cfg' {storeNtfsFile = Just testStoreNtfsFile, serverStatsBackupFile = Just testServerStatsBackupFile}

tests/SMPProxyTests.hs

@@ -77,7 +77,7 @@ smpProxyTests = do
     let srv1 = SMPServer testHost testPort testKeyHash
         srv2 = SMPServer testHost2 testPort2 testKeyHash
     describe "client API" $ do
-      let maxLen = maxMessageLength encryptedBlockSMPVersion
+      let maxLen = maxMessageLength
       describe "one server" $ do
         it "deliver via proxy" . oneServer $ do
           deliverMessageViaProxy srv1 srv1 C.SEd448 "hello 1" "hello 2"
@@ -137,10 +137,6 @@ smpProxyTests = do
           agentDeliverMessageViaProxy ([srv1], SPMNever, False) ([srv2], SPMNever, False) C.SEd448 "hello 1" "hello 2" 1
         it "first via proxy for unknown" . twoServers $
           agentDeliverMessageViaProxy ([srv1], SPMUnknown, True) ([srv1, srv2], SPMUnknown, False) C.SEd448 "hello 1" "hello 2" 1
-        it "without proxy with fallback" . twoServers_ proxyCfg cfgV7 $
-          agentDeliverMessageViaProxy ([srv1], SPMUnknown, False) ([srv2], SPMUnknown, False) C.SEd448 "hello 1" "hello 2" 3
-        it "fails when fallback is prohibited" . twoServers_ proxyCfg cfgV7 $
-          agentViaProxyVersionError
         it "retries sending when destination or proxy relay is offline" $ \_ ->
           agentViaProxyRetryOffline
         it "retries sending when destination relay session disconnects in proxy" $ \_ ->
@@ -218,7 +214,7 @@ proxyConnectDeadRelay n d proxyServ = do
   g <- C.newRandom
   -- set up proxy
   ts <- getCurrentTime
-  pc' <- getProtocolClient g NRMInteractive (1, proxyServ, Nothing) defaultSMPClientConfig {serverVRange = mkVersionRange minServerSMPRelayVersion sendingProxySMPVersion} [] Nothing ts (\_ -> pure ())
+  pc' <- getProtocolClient g NRMInteractive (1, proxyServ, Nothing) defaultSMPClientConfig [] Nothing ts (\_ -> pure ())
   pc <- either (fail . show) pure pc'
   THAuthClient {} <- maybe (fail "getProtocolClient returned no thAuth") pure $ thAuth $ thParams pc
   -- get proxy session
@@ -232,7 +228,7 @@ agentDeliverMessageViaProxy :: (C.AlgorithmI a, C.AuthAlgorithm a) => (NonEmpty
 agentDeliverMessageViaProxy aTestCfg@(aSrvs, _, aViaProxy) bTestCfg@(bSrvs, _, bViaProxy) alg msg1 msg2 baseId =
   withAgent 1 aCfg (servers aTestCfg) testDB $ \alice ->
     withAgent 2 aCfg (servers bTestCfg) testDB2 $ \bob -> runRight_ $ do
-      (bobId, CCLink qInfo Nothing) <- A.createConnection alice NRMInteractive 1 True True SCMInvitation Nothing Nothing CR.IKPQOn SMSubscribe
+      (bobId, CCLink qInfo Nothing) <- A.createConnection alice NRMInteractive 1 True True SCMInvitation Nothing Nothing CR.IKPQOn False SMSubscribe
       aliceId <- A.prepareConnectionToJoin bob 1 True qInfo PQSupportOn
       sqSecured <- A.joinConnection bob NRMInteractive 1 aliceId True qInfo "bob's connInfo" PQSupportOn SMSubscribe
       liftIO $ sqSecured `shouldBe` True
@@ -288,7 +284,7 @@ agentDeliverMessagesViaProxyConc agentServers msgs =
     -- agent connections have to be set up in advance
     -- otherwise the CONF messages would get mixed with MSG
     prePair alice bob = do
-      (bobId, CCLink qInfo Nothing) <- runExceptT' $ A.createConnection alice NRMInteractive 1 True True SCMInvitation Nothing Nothing CR.IKPQOn SMSubscribe
+      (bobId, CCLink qInfo Nothing) <- runExceptT' $ A.createConnection alice NRMInteractive 1 True True SCMInvitation Nothing Nothing CR.IKPQOn False SMSubscribe
       aliceId <- runExceptT' $ A.prepareConnectionToJoin bob 1 True qInfo PQSupportOn
       sqSecured <- runExceptT' $ A.joinConnection bob NRMInteractive 1 aliceId True qInfo "bob's connInfo" PQSupportOn SMSubscribe
       liftIO $ sqSecured `shouldBe` True
@@ -334,18 +330,6 @@ agentDeliverMessagesViaProxyConc agentServers msgs =
     aCfg = agentCfg {sndAuthAlg = C.AuthAlg C.SEd448, rcvAuthAlg = C.AuthAlg C.SEd448}
     servers srvs = (initAgentServersProxy_ SPMAlways SPFAllow) {smp = userServers srvs}
 
-agentViaProxyVersionError :: IO ()
-agentViaProxyVersionError =
-  withAgent 1 agentCfg (servers [SMPServer testHost testPort testKeyHash]) testDB $ \alice -> do
-    Left (A.BROKER _ (TRANSPORT TEVersion)) <-
-      withAgent 2 agentCfg (servers [SMPServer testHost2 testPort2 testKeyHash]) testDB2 $ \bob -> runExceptT $ do
-        (_bobId, CCLink qInfo Nothing) <- A.createConnection alice NRMInteractive 1 True True SCMInvitation Nothing Nothing CR.IKPQOn SMSubscribe
-        aliceId <- A.prepareConnectionToJoin bob 1 True qInfo PQSupportOn
-        A.joinConnection bob NRMInteractive 1 aliceId True qInfo "bob's connInfo" PQSupportOn SMSubscribe
-    pure ()
-  where
-    servers srvs = (initAgentServersProxy_ SPMUnknown SPFProhibit) {smp = userServers srvs}
-
 agentViaProxyRetryOffline :: IO ()
 agentViaProxyRetryOffline = do
   let srv1 = SMPServer testHost testPort testKeyHash
@@ -359,7 +343,7 @@ agentViaProxyRetryOffline = do
       let pqEnc = CR.PQEncOn
       withServer $ \_ -> do
         (aliceId, bobId) <- withServer2 $ \_ -> runRight $ do
-          (bobId, CCLink qInfo Nothing) <- A.createConnection alice NRMInteractive 1 True True SCMInvitation Nothing Nothing CR.IKPQOn SMSubscribe
+          (bobId, CCLink qInfo Nothing) <- A.createConnection alice NRMInteractive 1 True True SCMInvitation Nothing Nothing CR.IKPQOn False SMSubscribe
           aliceId <- A.prepareConnectionToJoin bob 1 True qInfo PQSupportOn
           sqSecured <- A.joinConnection bob NRMInteractive 1 aliceId True qInfo "bob's connInfo" PQSupportOn SMSubscribe
           liftIO $ sqSecured `shouldBe` True
@@ -442,14 +426,14 @@ agentViaProxyRetryNoSession = do
 testNoProxy :: AStoreType -> IO ()
 testNoProxy msType = do
   withSmpServerConfigOn (transport @TLS) (cfgMS msType) testPort2 $ \_ -> do
-    testSMPClient_ "127.0.0.1" testPort2 proxyVRangeV8 Nothing $ \(th :: THandleSMP TLS 'TClient) -> do
+    testSMPClient_ "127.0.0.1" testPort2 supportedServerSMPRelayVRange Nothing $ \(th :: THandleSMP TLS 'TClient) -> do
       (_, _, reply) <- sendRecv th (Nothing, "0", NoEntity, SMP.PRXY testSMPServer Nothing)
       reply `shouldBe` Right (SMP.ERR $ SMP.PROXY SMP.BASIC_AUTH)
 
 testProxyAuth :: AStoreType -> IO ()
 testProxyAuth msType = do
   withSmpServerConfigOn (transport @TLS) proxyCfgAuth testPort $ \_ -> do
-    testSMPClient_ "127.0.0.1" testPort proxyVRangeV8 Nothing $ \(th :: THandleSMP TLS 'TClient) -> do
+    testSMPClient_ "127.0.0.1" testPort supportedServerSMPRelayVRange Nothing $ \(th :: THandleSMP TLS 'TClient) -> do
       (_, _, reply) <- sendRecv th (Nothing, "0", NoEntity, SMP.PRXY testSMPServer2 $ Just "wrong")
       reply `shouldBe` Right (SMP.ERR $ SMP.PROXY SMP.BASIC_AUTH)
   where
@@ -459,7 +443,7 @@ testProxyAuth msType = do
 -- On success the reply is PKEY; otherwise it is the proxy error for the relay connection.
 requestRelaySession :: IO (Either SMP.ErrorType SMP.BrokerMsg)
 requestRelaySession =
-  testSMPClient_ "localhost" testPort proxyVRangeV8 Nothing $ \(th :: THandleSMP TLS 'TClient) ->
+  testSMPClient_ "localhost" testPort supportedServerSMPRelayVRange Nothing $ \(th :: THandleSMP TLS 'TClient) ->
     (\(_, _, reply) -> reply) <$> sendRecv th (Nothing, "1", NoEntity, SMP.PRXY testSMPServer2 Nothing)
 
 -- Shared "phase 2" of the reconnection tests: start a healthy relay, confirm it is reachable
@@ -468,7 +452,7 @@ requestRelaySession =
 requireProxyReconnect :: IO ()
 requireProxyReconnect =
   withSmpServerConfigOn (transport @TLS) proxyCfgJ2 testPort2 $ \_ -> do
-    testSMPClient_ "127.0.0.1" testPort2 proxyVRangeV8 Nothing $ \(th :: THandleSMP TLS 'TClient) -> do
+    testSMPClient_ "127.0.0.1" testPort2 supportedServerSMPRelayVRange Nothing $ \(th :: THandleSMP TLS 'TClient) -> do
       (_, _, reply) <- sendRecv th (Nothing, "0", NoEntity, SMP.PING)
       reply `shouldBe` Right SMP.PONG
     threadDelay 1500000 -- > persistErrorInterval (1s), so the stored connection error has expired
@@ -520,14 +504,14 @@ testAgentClientReconnectAfterCancel :: IO ()
 testAgentClientReconnectAfterCancel =
   withAgent 1 agentCfg agentServersLeak testDB $ \a -> do
     withStallingServerOn testPort2 $ do
-      t <- async $ runExceptT $ A.createConnection a NRMInteractive 1 True True SCMInvitation Nothing Nothing CR.IKPQOn SMSubscribe
+      t <- async $ runExceptT $ A.createConnection a NRMInteractive 1 True True SCMInvitation Nothing Nothing CR.IKPQOn False SMSubscribe
       threadDelay 1000000 -- let the connect to the stalling relay start, then kill it mid-flight
       cancel t
     withSmpServerConfigOn (transport @TLS) cfgJ2 testPort2 $ \_ -> do
-      testSMPClient_ "127.0.0.1" testPort2 proxyVRangeV8 Nothing $ \(th :: THandleSMP TLS 'TClient) -> do
+      testSMPClient_ "127.0.0.1" testPort2 supportedServerSMPRelayVRange Nothing $ \(th :: THandleSMP TLS 'TClient) -> do
         (_, _, reply) <- sendRecv th (Nothing, "0", NoEntity, SMP.PING)
         reply `shouldBe` Right SMP.PONG -- the relay is up and reachable, so a timeout can only be the poisoned var
-      r <- timeout 8000000 $ runExceptT $ A.createConnection a NRMInteractive 1 True True SCMInvitation Nothing Nothing CR.IKPQOn SMSubscribe
+      r <- timeout 8000000 $ runExceptT $ A.createConnection a NRMInteractive 1 True True SCMInvitation Nothing Nothing CR.IKPQOn False SMSubscribe
       case r of
         Just (Right _) -> pure ()
         _ -> expectationFailure $ "agent failed to connect after a cancelled connect; got: " <> show r

tests/ServerTests.hs

@@ -56,7 +56,6 @@ import Simplex.Messaging.Server.StoreLog (StoreLogRecord (..), closeStoreLog)
 import Simplex.Messaging.Transport
 import Simplex.Messaging.Transport.Credentials
 import Simplex.Messaging.Util (whenM)
-import Simplex.Messaging.Version (mkVersionRange)
 import System.Directory (doesDirectoryExist, doesFileExist, removeDirectoryRecursive, removeFile)
 import System.IO (IOMode (..), withFile)
 import System.TimeIt (timeItT)
@@ -261,12 +260,12 @@ testCreateSecure =
       Resp "dabc" _ err5 <- sendRecv s ("", "dabc", sId, _SEND "hello")
       (err5, ERR AUTH) #== "rejects unsigned SEND"
 
-      let maxAllowedMessage = B.replicate (maxMessageLength currentClientSMPRelayVersion) '-'
+      let maxAllowedMessage = B.replicate maxMessageLength '-'
       Resp "bcda" _ OK <- signSendRecv s sKey ("bcda", sId, _SEND maxAllowedMessage)
       Resp "" _ (Msg mId3 msg3) <- tGet1 r
       (dec mId3 msg3, Right maxAllowedMessage) #== "delivers message of max size"
 
-      let biggerMessage = B.replicate (maxMessageLength currentClientSMPRelayVersion + 1) '-'
+      let biggerMessage = B.replicate (maxMessageLength + 1) '-'
       Resp "bcda" _ (ERR LARGE_MSG) <- signSendRecv s sKey ("bcda", sId, _SEND biggerMessage)
       pure ()
 
@@ -308,12 +307,12 @@ testCreateSndSecure =
       Resp "dabc" _ err5 <- sendRecv s ("", "dabc", sId, _SEND "hello")
       (err5, ERR AUTH) #== "rejects unsigned SEND"
 
-      let maxAllowedMessage = B.replicate (maxMessageLength currentClientSMPRelayVersion) '-'
+      let maxAllowedMessage = B.replicate maxMessageLength '-'
       Resp "bcda" _ OK <- signSendRecv s sKey ("bcda", sId, _SEND maxAllowedMessage)
       Resp "" _ (Msg mId3 msg3) <- tGet1 r
       (dec mId3 msg3, Right maxAllowedMessage) #== "delivers message of max size"
 
-      let biggerMessage = B.replicate (maxMessageLength currentClientSMPRelayVersion + 1) '-'
+      let biggerMessage = B.replicate (maxMessageLength + 1) '-'
       Resp "bcda" _ (ERR LARGE_MSG) <- signSendRecv s sKey ("bcda", sId, _SEND biggerMessage)
       pure ()
 
@@ -1272,7 +1271,7 @@ testTiming =
   describe "should have similar time for auth error, whether queue exists or not, for all key types" $
     forM_ timingTests $ \tst ->
       it (testName tst) $ \(ATransport t, msType) ->
-        smpTest2Cfg (cfgMS msType) (mkVersionRange minServerSMPRelayVersion authCmdsSMPVersion) t $ \rh sh ->
+        smpTest2Cfg (cfgMS msType) supportedServerSMPRelayVRange t $ \rh sh ->
           testSameTiming rh sh tst msType
   where
     testName :: (C.AuthAlg, C.AuthAlg, Int) -> String
@@ -1305,7 +1304,11 @@ testTiming =
       (dhPub, dhPriv :: C.PrivateKeyX25519) <- atomically $ C.generateKeyPair g
       Resp "abcd" NoEntity (Ids rId sId srvDh) <- signSendRecv rh rKey ("abcd", NoEntity, New rPub dhPub)
       let dec = decryptMsgV3 $ C.dh' srvDh dhPriv
-      Resp "cdab" _ OK <- signSendRecv rh rKey ("cdab", rId, SUB)
+      Resp "cdab" _ resp <- signSendRecv rh rKey ("cdab", rId, SUB)
+      case resp of
+        OK -> pure ()
+        SOK Nothing -> pure ()
+        r -> expectationFailure $ "unexpected response: " <> show r
 
       (_, badKey) <- atomically $ C.generateAuthKeyPair badKeyAlg g
       runTimingTest rh badKey rId SUB

tests/XFTPAgent.hs

@@ -41,6 +41,7 @@ import qualified Simplex.Messaging.Crypto.File as CF
 import Simplex.Messaging.Encoding.String (StrEncoding (..))
 import Simplex.Messaging.Protocol (BasicAuth, NetworkError (..), ProtoServerWithAuth (..), ProtocolServer (..), XFTPServerWithAuth)
 import Simplex.Messaging.Server.Expiration (ExpirationConfig (..))
+import Simplex.Messaging.Server.Information (ServerPublicInfo)
 import Simplex.Messaging.Util (tshow)
 import System.Directory (doesDirectoryExist, doesFileExist, getFileSize, listDirectory, removeFile)
 import System.FilePath ((</>))
@@ -82,19 +83,19 @@ xftpAgentTests =
       it "if file is expired on server, should report error and continue receiving next file" testXFTPAgentExpiredOnServer
       it "should request additional recipient IDs when number of recipients exceeds maximum per request" testXFTPAgentRequestAdditionalRecipientIDs
       describe "XFTP server test via agent API" $ do
-        it "should pass without basic auth" $ \_ -> testXFTPServerTest Nothing (noAuthSrv testXFTPServer2) `shouldReturn` Nothing
+        it "should pass without basic auth" $ \_ -> testXFTPServerTest Nothing (noAuthSrv testXFTPServer2) `shouldReturn` Right Nothing
         let srv1 = testXFTPServer2 {keyHash = "1234"}
         it "should fail with incorrect fingerprint" $ \_ -> do
-          testXFTPServerTest Nothing (noAuthSrv srv1) `shouldReturn` Just (ProtocolTestFailure TSConnect $ BROKER (B.unpack $ strEncode srv1) $ NETWORK NEUnknownCAError)
+          testXFTPServerTest Nothing (noAuthSrv srv1) `shouldReturn` Left (ProtocolTestFailure TSConnect $ BROKER (B.unpack $ strEncode srv1) $ NETWORK NEUnknownCAError)
         describe "server with password" $ do
           let auth = Just "abcd"
               srv = ProtoServerWithAuth testXFTPServer2
-              authErr = Just (ProtocolTestFailure TSCreateFile $ XFTP (B.unpack $ strEncode testXFTPServer2) AUTH)
-          it "should pass with correct password" $ \_ -> testXFTPServerTest auth (srv auth) `shouldReturn` Nothing
-          it "should fail without password" $ \_ -> testXFTPServerTest auth (srv Nothing) `shouldReturn` authErr
-          it "should fail with incorrect password" $ \_ -> testXFTPServerTest auth (srv $ Just "wrong") `shouldReturn` authErr
+              authErr = ProtocolTestFailure TSCreateFile $ XFTP (B.unpack $ strEncode testXFTPServer2) AUTH
+          it "should pass with correct password" $ \_ -> testXFTPServerTest auth (srv auth) `shouldReturn` Right Nothing
+          it "should fail without password" $ \_ -> testXFTPServerTest auth (srv Nothing) `shouldReturn` Left authErr
+          it "should fail with incorrect password" $ \_ -> testXFTPServerTest auth (srv $ Just "wrong") `shouldReturn` Left authErr
 
-testXFTPServerTest :: HasCallStack => Maybe BasicAuth -> XFTPServerWithAuth -> IO (Maybe ProtocolTestFailure)
+testXFTPServerTest :: HasCallStack => Maybe BasicAuth -> XFTPServerWithAuth -> IO (Either ProtocolTestFailure (Maybe (Either String ServerPublicInfo)))
 testXFTPServerTest newFileBasicAuth srv =
   withXFTPServerCfg testXFTPServerConfig {newFileBasicAuth, xftpPort = xftpTestPort2} $ \_ ->
     -- initially passed server is not running
@@ -680,9 +681,3 @@ testXFTPAgentRequestAdditionalRecipientIDs = withXFTPServer $ do
     void $ testReceive rcp (rfds !! 99) filePath
     void $ testReceive rcp (rfds !! 299) filePath
     void $ testReceive rcp (rfds !! 499) filePath
-
-testXFTPServerTest_ :: HasCallStack => XFTPServerWithAuth -> IO (Maybe ProtocolTestFailure)
-testXFTPServerTest_ srv =
-  -- initially passed server is not running
-  withAgent 1 agentCfg initAgentServers testDB $ \a ->
-    testProtocolServer a NRMInteractive 1 srv

tests/XFTPCLI.hs

@@ -9,10 +9,11 @@ import Simplex.FileTransfer.Client.Main
     xftpClientDeprecationNotice,
   )
 import Simplex.FileTransfer.Description (kb, mb)
+import Simplex.FileTransfer.Util (safeFileNameStr, uniqueCombine)
 import System.Directory (createDirectoryIfMissing, getFileSize, listDirectory, removeDirectoryRecursive)
 import System.Environment (withArgs)
 import System.Exit (ExitCode (ExitSuccess))
-import System.FilePath ((</>))
+import System.FilePath (takeFileName, (</>))
 import System.IO.Silently (capture, capture_)
 import Test.Hspec hiding (fit, it)
 import Util
@@ -29,6 +30,18 @@ xftpCLIFileTests = around_ testBracket $ do
   it "should delete file from 2 servers" $ \fsType ->
     withXFTPServerConfigOn (cfgFS fsType) $ \_ -> withXFTPServerConfigOn (cfgFS2 fsType) $ \_ -> testXFTPCLIDelete_
   it "prepareChunkSizes should use 2 chunk sizes" $ \_ -> testPrepareChunkSizes
+  describe "received file name" $ do
+    it "sanitizes any name to a real file name" $ \_ ->
+      filter (not . sanitized) fileNames `shouldBe` []
+    it "sanitizes to a name with no directory components" $ \_ ->
+      filter (not . bareName) fileNames `shouldBe` []
+    it "combines a sanitized name inside the destination folder" $ \_ ->
+      testReceivedFileNameCombine
+  where
+    fileNames :: [FilePath]
+    fileNames = ["", ".", "..", "...", "../x", "../../etc/passwd", "/etc/cron.d/x", "a/b", "x/", "test.pdf", ".hidden", "a b.tar.gz"]
+    sanitized n = let n' = safeFileNameStr n in n' /= "" && n' /= "." && n' /= ".."
+    bareName n = let n' = safeFileNameStr n in n' == takeFileName n'
 
 testBracket :: IO () -> IO ()
 testBracket =
@@ -162,6 +175,10 @@ testXFTPCLIDelete_ = do
   xftpCLI ["recv", fdRcv2, recipientFiles, "--tmp=tests/tmp"]
     `shouldThrow` anyException
 
+testReceivedFileNameCombine :: IO ()
+testReceivedFileNameCombine =
+  uniqueCombine recipientFiles "../../escaped.txt" `shouldReturn` (recipientFiles </> "escaped.txt")
+
 testPrepareChunkSizes :: IO ()
 testPrepareChunkSizes = do
   prepareChunkSizes (mb 9 + kb 256) `shouldBe` [mb 4, mb 4, mb 1, mb 1]