catch IOErrors in getRelay

mark proxy timeouts as temporary
revert String encoding, discard invalid errors in QC
2026-08-30 11:58:22 +00:00 · 2024-04-22 20:10:06 +03:00 · 2024-04-22 20:09:08 +03:00 · 2024-04-19 13:06:32 +03:00 · 2024-04-18 23:35:21 +01:00 · 2024-04-18 23:35:21 +01:00
58 changed files with 1413 additions and 947 deletions
@@ -49,7 +49,7 @@ jobs:
        run: cabal build --enable-tests

      - name: Test
-        timeout-minutes: 30
+        timeout-minutes: 40
        shell: bash
        run: cabal test --test-show-details=direct

@@ -1,62 +1,3 @@
-# 5.7.5
-
-SMP agent:
- fail if non-unique connection IDs are passed to sendMessages (to prevent client errors and deadlocks).
-
-# 5.7.4
-
-SMP agent:
- remove re-subscription timeouts (as they are tracked per operation, and could cause failed subscriptions).
- reconnect XFTP clients when network settings changes.
- fix lock contention resulting in stuck subscriptions on network change.
-
-# 5.7.3
-
-SMP/NTF protocol:
- add ALPN for handshake version negotiation, similar to XFTP (to preserve backwards compatibility with the old clients).
- upgrade clients to versions v7/v2 of the protocols.
-
-SMP server:
- faster responses to subscription requests.
-
-XFTP client:
- fix network exception during file download treated as permanent file error.
-
-SMP agent:
- do not report subscription timeouts while client is offline.
-
-# 5.7.2
-
-SMP agent:
- fix connections failing when connecting via link due to race condition on slow network.
- remove concurrency limit when waiting for connection subscription.
- remove TLS timeout.
-
-# 5.7.1
-
-SMP agent:
- increase timeout for TLS connection via SOCKS
-
-# 5.7.0
-
-Version 5.7.0.4
-
-_Please note_: the earliest SimpleX Chat clients supported by this version of the servers is 5.5.3 (released on February 11, 2024).
-
-SMP server:
- increase max SMP protocol version to 7 (support for deniable authenticators).
-
-NTF server:
- increase max NTF protocol version to 2 (support for deniable authenticators).
-
-XFTP server:
- version handshake using ALPN.
-
-SMP agent:
- increase timeouts for XFTP files.
- don't send commands after timeout.
- PQ encryption support.
-
 # 5.6.2

 Version 5.6.2.2.
@@ -0,0 +1,23 @@
+common:
+  corrId - random BS, used as CbNonce
+  entityId - p2r tlsUniq
+
+# setup
+s->p: "proxy", uri, auth?
+  # unless connected
+  p->r: "p_handshake"
+  p<-r: "r_key", tls-signed dh pub
+s<-r: "r_key", tls-signed dh pub # reply entityId contains tlsUniq
+
+# working
+s ; generate random dh priv, make shared secret
+s->p: s2r("forward", random dh pub, SEND command blob)
+  p->r: p2r("forward", random dh pub, s2r("forward", ...)))
+    r->c@ "msg", ...
+  p<-r: p2r("r_res", s2r("ok" / "error", error))
+s<-p@ s2r("ok" / "error", error)
+
+# expired
+  p<-r@ p2r("error", "key expired")
+s<-p@ "error", "key expired"
+s ; reconnect
@@ -1,5 +1,5 @@
 name: simplexmq
-version: 5.7.5.0
+version: 5.6.2.2
 synopsis: SimpleXMQ message broker
 description: |
  This package includes <./docs/Simplex-Messaging-Server.html server>,
@@ -2,9 +2,9 @@

 ## Problem

-SMP protocol relays are chosen and can be controlled by the message recipients. It means that the recipients can find out IP addresses of message senders by modifying SMP relay code (or by using proxies and timing correlation), unless the senders use VPN or some overlay network. Tor is an audequate solution in most cases to mitigate it, but it requires additional technical knowledge to install and configure (even installing Orbot on Android is seen as "complex" by many users), and reduces usability because of higher latency.
+SMP protocol relays are chosen and can be controlled by the message recipients. It means that the recipients can find out IP addresses of message senders by modifying SMP relay code (or by using proxies and timing correlation), unless the senders use VPN or some overlay network. Tor is an adequate solution in most cases to mitigate it, but it requires additional technical knowledge to install and configure (even installing Orbot on Android is seen as "complex" by many users), and reduces usability because of higher latency.

-The lack of in-built IP address protection is the main concern of many users, particularly given that most people do not realise that it is lacking by default - without transport protection SimpleX is not perceived as a "whole product".
+The lack of in-built IP address protection is the main concern of many users, particularly given that most people do not realize that it is lacking by default - without transport protection SimpleX is not perceived as a "whole product".

 Similarly, XFTP protocol relays are chosen by senders, and they can be used to detect file recipients' IP addresses.

@@ -43,7 +43,7 @@ Overall, this is not a viable or even appropriate option for the current stage.

 3. SMP / XFTP proxy.

-Introduce SMP and XFTP protocol extenstions to allow message senders and file recipients to delegate the tasks of sending messages and receiving files to the proxies, so that peer-chosen relays can only observe IP addresses of the proxies and not of the users.
+Introduce SMP and XFTP protocol extensions to allow message senders and file recipients to delegate the tasks of sending messages and receiving files to the proxies, so that peer-chosen relays can only observe IP addresses of the proxies and not of the users.

 Pros:
 - no dependency on and lower latency than via Tor
@@ -68,7 +68,7 @@ Below considers this design.

 2. SMP proxy should not be able to observe queue addresses and their count on the destination relays. This requirement is not needed for XFTP proxies, as each file chunk is downloaded only once, so there is no need to hide its address.

-3. There must be no identifiers and cyphertext in common in outgoing and incoming traffic inside TLS (the current designs have this quality).
+3. There must be no identifiers and ciphertext in common in outgoing and incoming traffic inside TLS (the current designs have this quality).

 4. Traffic between the client and destination relays must be e2e encrypted, with MITM-by-proxy mitigated, relying on the relay identity (certificate fingerprint), ideally without any additional fingerprint in relay address.

@@ -97,11 +97,11 @@ This would also reduce the difference in how the traffic looks to the observer -

 The flow of the messages will be:

-1. Client requests proxy to create session with the relay by sending `server` command with the SMP relay address and optional proxy basic AUTH (below). It should be possible to batch multiple session requests into one block, to reduce traffic.
+1. Client requests proxy to create session with the relay by sending `PRXY` command with the SMP relay address and optional proxy basic AUTH (below). It should be possible to batch multiple session requests into one block, to reduce traffic.

-2. Proxy connects to SMP relay, negotiating a shared secret in the handshake that will be used to encrypt all sender blocks inside TLS (proxy-relay encryption). SMP relay also returns in handshake its temporary DH key to agree e2e encryption with the client (sender-relay encryption, to hide metadata sent to the destination relay from proxy).
+2. Proxy connects to SMP relay, negotiating a shared secret via a handshake headers - it will be used to encrypt all sender blocks inside TLS (proxy-relay encryption). DH key returned by SMP relay in handshake will also be used to encrypt client commands, combining it with random per-command keys (sender-relay encryption, to hide metadata sent to the destination relay from proxy).

-3. Proxy replies with `server_id` command including relay session ID to identify it in further requests, relay DH key for e2e encryption with the client - this key is signed with the TLS online private key associated with the certificate (its fingerprint is included in the relay address), and the TLS session ID between proxy and relay (this session ID must be used in transmissions, to mitigate replay attacks as before).
+3. Proxy replies to sender with `PKEY` message using "entityId" transmission field to indicate session ID for using in further requests, relay DH key for _s2r_ encryption with the client - this key is signed with the TLS online private key associated with the certificate (its fingerprint is included in the relay address), and the TLS session ID between proxy and relay (this session ID must be used in transmissions, to mitigate replay attacks as before).

 A possible attack here is that proxy can use this TLS session to replay commands received from the client. Possibly, it could be mitigated with a bloom filter per proxy/SMP relay connection that would reject the repeated DH keys (that need to be used for replay), and also with DH key expiration (this mitigation should allow some acceptable rate of false positives from the bloom filter).

@@ -113,11 +113,11 @@ It is important that the same public key from destination relay is returned to a

 *Unrelated cosideration for SMP protocol privacy improvement*: instead of signing commands to the destination relay, the sender could have a ratchet per queue agreed with the destination relay that would simply use authenticated encryption with per-message symmetric key to encrypt the message on the way to relay, and this encryption would be used as a proof of sender.

-4. Now the client sends `forward` to proxy, which it then forwards to SMP relay, applying additional encryption layer.
+4. Now the client sends `PFWD` to proxy, which it then forwards to SMP relay as `RFWD`, applying _p2r_ encryption layer.

-5. SMP relay sends `response` to proxy applying additional encryption layer, which it then forwards to the client removing the additional encryption layer.
+5. SMP relay sends `RRES` to proxy applying _p2r_ encryption layer, which it then forwards to the client as `PRES`, removing the _p2r_ encryption layer.

-Effectively it works as a simplified two-hop onion routing with the first relay (proxy) chosen by the sending client and the second relay chosen by the recipient, not only protecting senders' IP addresses from the recipients' relays, but also preventing recipients relays from correlating senders' traffic to different queues, as TLS session is owned by the proxy now and it mixes the traffic from multiple senders. To correlate traffic to users, proxy and relay would have to combine their information. SMP relays are still able to correlate traffic to receiving users via transport session.
+Effectively it works as a simplified two-hop onion routing with the first relay (proxy) chosen by the sending client and the second relay chosen by the recipient, not only protecting senders' IP addresses from the recipients' relays, but also preventing recipients' relays from correlating senders' traffic to different queues, as TLS session is owned by the proxy now and it mixes the traffic from multiple senders. To correlate traffic to users, proxy and relay would have to combine their information. SMP relays are still able to correlate traffic to receiving users via transport session.

 Sequence diagram for sending the message via SMP proxy:

@@ -126,33 +126,33 @@ Sequence diagram for sending the message via SMP proxy:
 |  sending  |               |    SMP    |                     |    SMP    |              | receiving |
 |  client   |               |   proxy   |                     |   relay   |              |  client   |
 -------------               -------------                     -------------              -------------
-     |       `server`             |                                 |                          |
-     | -------------------------> |   create TLS session, get keys  |                          |
+     |           `PRXY`           |                                 |                          |
+     | -------------------------> |                                 |                          |
     |                            | ------------------------------> |                          |
-     |        `server_id`         |       (if doesn't exist)        |                          |
+     |                            |          SMP handshake          |                          |
+     |                            | <------------------------------ |                          |
+     |           `PKEY`           |                                 |                          |
     | <------------------------- |                                 |                          |
     |                            |                                 |                          |
-     | TLS(F:s2r(SEND(e2e(msg)))) |                                 |                          |
-     | -------------------------> | TLS(F:p2r(s2r(SEND(e2e(msg))))) |                          |
+     |        `PFWD` (s2r)        |                                 |                          |
+     | -------------------------> |                                 |                          |
+     |                            |           `RFWD` (p2r)          |                          |
     |                            | ------------------------------> |                          |
-     |                            |                                 |                          |
-     |                            |     TLS(R:p2r(s2r(OK/ERR)))     |                          |
-     |     TLS(R:s2r(OK/ERR))     | <------------------------------ |                          |
-     | <------------------------- |                                 | TLS(MSG(r2c(e2e(msg))))  |
-     |                            |                                 | -----------------------> |
-     |                            |                                 |                          |
-     |                            |                                 |        TLS(ACK)          |
+     |                            |           `RRES` (p2r)          |                          |
+     |                            | <------------------------------ |                          |
+     |        `PRES` (s2r)        |                                 |           `MSG`          |
+     | <------------------------- |                                 | -----------------------> |
+     |                            |                                 |           `ACK`          |
     |                            |                                 | <----------------------- |
     |                            |                                 |                          |
     |                            |                                 |                          |
-
 ```

-Below diagram shows the encrypttion layers for `forward` and `response` commands:
+Below diagram shows the encrypttion layers for `PFWD`/`RFWD` commands and `RRES`/`PRES` responses:

- s2r (added) - encryption between client and SMP relay, with relay key returned in server_id command, with MITM by proxy mitigated by verifying the certificate fingerprint included in the relay address.
+- s2r (added) - encryption between client and SMP relay, with relay key returned in relay handshake, with MITM by proxy mitigated by verifying the certificate fingerprint included in the relay address.
 - e2e (exists now) - end-to-end encryption per SMP queue, with double ratchet e2e encryption inside it.
- p2r (added) - additional encryption between proxy and SMP relay with key agreed in the handshake, to mitigate traffic correlation inside TLS. This key could also be signed by the same certificate, if we don't want to rely on TLS security.
+- p2r (added) - additional encryption between proxy and SMP relay with the shared secret agreed in the handshake, to mitigate traffic correlation inside TLS.
 - r2c (exists now) additional encryption between SMP relay and client to prevent traffic correlation inside TLS.

 ```
@@ -167,27 +167,32 @@ Below diagram shows the encrypttion layers for `forward` and `response` commands
 -----------------             -----------------  -- TLS --  -----------------             -----------------
 ```

-When proxy connects to SMP relay it would indicate in the handshake that it will use proxy protocol and the SMP relay would expect the same `forward` commands and reply with `response`s.
+Question: should proxy declare its role in handshake? When proxy connects to SMP relay it would indicate in the handshake that it will act as a proxy and the SMP relay would expect the same `forward` commands and reply with `response`s.

-Below syntax aims to fit in 16kb block using spare capacity in SMP protocol.
+Common SMP transmission format (v4), for reference:

 ```abnf
-proxy_block = padded(proxy_transmission, 16384)
-proxy_transmission = corr_id relay_session_id proxy_command
-corr_id = length *8 OCTET
-proxy_command = server / server_id / forward / response / error
-server = "S" address [relay_basic_auth] ; creates transport session between proxy and relay
-server_id = "I" relay_session_id tls_session_id signed_relay_key ;
-    ; session_id is the TLS session ID between proxy and relay, it has to be included inside encrypted block to prevent replay attacks
-forward = %s"F" random_dh_pub_key encrypted_block ; it's important that a new key is used for each command, to prevent any correlation by proxy or by destination relay
-response = %s"R" encrypted_block; response received from the destination SMP relay
-relay_session_id = length *8 OCTET
-error = %s"E" error
+paddedTransmission = <padded(transmission), 16384>
+transmission = signature signed
+signature = 0 ; empty signatures here
+signed = sessionIdentifier corrId entityId (smpCommand / brokerMsg)
 ```

-The overhead is: 1+8 (corrId) + 1+8 (relay_session_id) + 1 (command) + 1+32 (random_dh_pub_key) + 2 (original length) + 16 (auth tag for e2e encryption) + 16 (auth tag for proxy to relay encryption) = 86 bytes. The reserve for sent messages in SMP is ~84 bytes, so it should about fit with some reduced bytes somewhere.
+- `corrId` is fully random each time and used as a nonce for encrypted blocks.
+- `entityId` carries tlsUniq from the current proxy-to-relay connection.
+- `smpCommand` gets extended with `s2p_command / p2r_command`.
+- `brokerMsg` gets extended with `r_key / r_response`.

-Another possible design is to allow mixing sent messages and normal SMP commands in the same transport connection, but it can make fitting in the block a bit harder, additional overhead would be: 1 (transmission count) + 2 (transmission size) + 1 (empty signature) = 4 bytes.
+```abnf
+s2p_command = proxy / forward
+p2r_command = p_handshake ; forward is
+proxy = %s"PRXY" SP relayUri SP basicAuth
+relayUri = length %s"smp://" serverIdentity "@" srvHost [":" port]
+forward = %s"PFWD" SP dhPublic SP encryptedBlock
+r_key = %s"PKEY" SP dhPublic
+r_response = %s"RRES" SP encryptedBlock
+dhPublic = length x509encoded
+```

 The above assumes that the client can only send one message to an SMP relay and then has to wait for response before sending the next message. Missing the response would cause re-delivery (further improvement is possible when proxy detects these redelieveries and not send them to relays but simply reply with the same response).

@@ -5,7 +5,7 @@ cabal-version: 1.12
 -- see: https://github.com/sol/hpack

 name:           simplexmq
-version:        5.7.5.0
+version:        5.6.2.2
 synopsis:       SimpleXMQ message broker
 description:    This package includes <./docs/Simplex-Messaging-Server.html server>,
                <./docs/Simplex-Messaging-Client.html client> and
@@ -652,6 +652,7 @@ test-suite simplexmq-test
      ServerTests
      SMPAgentClient
      SMPClient
+      SMPProxyTests
      Util
      XFTPAgent
      XFTPCLI
@@ -180,7 +180,7 @@ runXFTPRcvWorker c srv Worker {doWork} = do
        fc@RcvFileChunk {userId, rcvFileId, rcvFileEntityId, digest, fileTmpPath, replicas = replica@RcvFileChunkReplica {rcvChunkReplicaId, server, delay} : _} -> do
          let ri' = maybe ri (\d -> ri {initialInterval = d, increaseAfter = 0}) delay
          withRetryIntervalLimit xftpConsecutiveRetries ri' $ \delay' loop -> do
-            liftIO $ waitForUserNetwork c
+            lift $ waitForUserNetwork c
            downloadFileChunk fc replica
              `catchAgentError` \e -> retryOnError "XFTP rcv worker" (retryLoop loop e delay') (retryDone e) e
          where
@@ -424,7 +424,7 @@ runXFTPSndPrepareWorker c Worker {doWork} = do
            tryCreate = do
              usedSrvs <- newTVarIO ([] :: [XFTPServer])
              withRetryInterval (riFast ri) $ \_ loop -> do
-                liftIO $ waitForUserNetwork c
+                lift $ waitForUserNetwork c
                createWithNextSrv usedSrvs
                  `catchAgentError` \e -> retryOnError "XFTP prepare worker" (retryLoop loop) (throwError e) e
              where
@@ -457,7 +457,7 @@ runXFTPSndWorker c srv Worker {doWork} = do
        fc@SndFileChunk {userId, sndFileId, sndFileEntityId, filePrefixPath, digest, replicas = replica@SndFileChunkReplica {sndChunkReplicaId, server, delay} : _} -> do
          let ri' = maybe ri (\d -> ri {initialInterval = d, increaseAfter = 0}) delay
          withRetryIntervalLimit xftpConsecutiveRetries ri' $ \delay' loop -> do
-            liftIO $ waitForUserNetwork c
+            lift $ waitForUserNetwork c
            uploadFileChunk cfg fc replica
              `catchAgentError` \e -> retryOnError "XFTP snd worker" (retryLoop loop e delay') (retryDone e) e
          where
@@ -624,7 +624,7 @@ runXFTPDelWorker c srv Worker {doWork} = do
        processDeletedReplica replica@DeletedSndChunkReplica {deletedSndChunkReplicaId, userId, server, chunkDigest, delay} = do
          let ri' = maybe ri (\d -> ri {initialInterval = d, increaseAfter = 0}) delay
          withRetryIntervalLimit xftpConsecutiveRetries ri' $ \delay' loop -> do
-            liftIO $ waitForUserNetwork c
+            lift $ waitForUserNetwork c
            deleteChunkReplica
              `catchAgentError` \e -> retryOnError "XFTP del worker" (retryLoop loop e delay') (retryDone e) e
          where
@@ -39,6 +39,7 @@ import Simplex.Messaging.Client
    proxyUsername,
    transportClientConfig,
  )
+import Simplex.Messaging.Client.Agent ()
 import qualified Simplex.Messaging.Crypto as C
 import qualified Simplex.Messaging.Crypto.Lazy as LC
 import Simplex.Messaging.Encoding (smpDecode, smpEncode)
@@ -184,9 +185,11 @@ xftpClientError = \case

 sendXFTPCommand :: forall p. FilePartyI p => XFTPClient -> C.APrivateAuthKey -> XFTPFileId -> FileCommand p -> Maybe XFTPChunkSpec -> ExceptT XFTPClientError IO (FileResponse, HTTP2Body)
 sendXFTPCommand c@XFTPClient {thParams} pKey fId cmd chunkSpec_ = do
+  -- TODO random corrId
+  let corrIdUsedAsNonce = ""
  t <-
    liftEither . first PCETransportError $
-      xftpEncodeAuthTransmission thParams pKey ("", fId, FileCmd (sFileParty @p) cmd)
+      xftpEncodeAuthTransmission thParams pKey (corrIdUsedAsNonce, fId, FileCmd (sFileParty @p) cmd)
  sendXFTPTransmission c t chunkSpec_

 sendXFTPTransmission :: XFTPClient -> ByteString -> Maybe XFTPChunkSpec -> ExceptT XFTPClientError IO (FileResponse, HTTP2Body)
@@ -244,13 +247,8 @@ downloadXFTPChunk g c@XFTPClient {config} rpKey fId chunkSpec@XFTPRcvChunkSpec {
        let dhSecret = C.dh' sDhKey rpDhKey
        cbState <- liftEither . first PCECryptoError $ LC.cbInit dhSecret cbNonce
        let t = chunkTimeout config chunkSize
-        ExceptT (sequence <$> (t `timeout` (download cbState `catches` errors))) >>= maybe (throwError PCEResponseTimeout) pure
+        ExceptT (sequence <$> (t `timeout` download cbState)) >>= maybe (throwError PCEResponseTimeout) pure
        where
-          errors =
-            [ Handler $ \(_e :: H.HTTP2Error) -> pure $ Left PCENetworkError,
-              Handler $ \(e :: IOException) -> pure $ Left (PCEIOError e),
-              Handler $ \(_e :: SomeException) -> pure $ Left PCENetworkError
-            ]
          download cbState =
            runExceptT . withExceptT PCEResponseError $
              receiveEncFile chunkPart cbState chunkSpec `catchError` \e ->
@@ -18,6 +18,7 @@ import Data.Text.Encoding (decodeUtf8)
 import Simplex.FileTransfer.Client
 import Simplex.Messaging.Agent.RetryInterval
 import Simplex.Messaging.Client (NetworkConfig (..), ProtocolClientError (..), temporaryClientError)
+import Simplex.Messaging.Client.Agent ()
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol (ProtocolServer (..), XFTPServer)
 import Simplex.Messaging.TMap (TMap)
@@ -48,6 +48,7 @@ import Simplex.Messaging.Protocol
    SndPublicAuthKey,
    Transmission,
    TransmissionForAuth (..),
+    CorrId (..),
    encodeTransmission,
    encodeTransmissionForAuth,
    messageTagP,
@@ -328,7 +329,7 @@ checkParty' c = case testEquality (sFileParty @p) (sFileParty @p') of
 xftpEncodeAuthTransmission :: ProtocolEncoding XFTPVersion e c => THandleParams XFTPVersion 'TClient -> C.APrivateAuthKey -> Transmission c -> Either TransportError ByteString
 xftpEncodeAuthTransmission thParams@THandleParams {thAuth} pKey (corrId, fId, msg) = do
  let TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth thParams (corrId, fId, msg)
-  xftpEncodeBatch1 . (,tToSend) =<< authTransmission thAuth (Just pKey) corrId tForAuth
+  xftpEncodeBatch1 . (,tToSend) =<< authTransmission thAuth (Just pKey) (C.cbNonce $ bs corrId) tForAuth

 xftpEncodeTransmission :: ProtocolEncoding XFTPVersion e c => THandleParams XFTPVersion p -> Transmission c -> Either TransportError ByteString
 xftpEncodeTransmission thParams (corrId, fId, msg) = do
@@ -13,9 +13,12 @@ import Control.Logger.Simple
 import Control.Monad
 import Control.Monad.IO.Unlift
 import Crypto.Random
+import Data.Default (def)
 import Data.Int (Int64)
+import Data.List (find)
 import Data.List.NonEmpty (NonEmpty)
 import qualified Data.Map.Strict as M
+import Data.Maybe (fromMaybe)
 import Data.Time.Clock (getCurrentTime)
 import Data.Word (Word32)
 import Data.X509.Validation (Fingerprint (..))
@@ -100,7 +103,7 @@ supportedXFTPhandshakes :: [ALPN]
 supportedXFTPhandshakes = ["xftp/1"]

 newXFTPServerEnv :: XFTPServerConfig -> IO XFTPEnv
-newXFTPServerEnv config@XFTPServerConfig {storeLogFile, fileSizeQuota, caCertificateFile, certificateFile, privateKeyFile, transportConfig} = do
+newXFTPServerEnv config@XFTPServerConfig {storeLogFile, fileSizeQuota, caCertificateFile, certificateFile, privateKeyFile} = do
  random <- liftIO C.newRandom
  store <- atomically newFileStore
  storeLog <- liftIO $ mapM (`readWriteFileStore` store) storeLogFile
@@ -109,7 +112,17 @@ newXFTPServerEnv config@XFTPServerConfig {storeLogFile, fileSizeQuota, caCertifi
  forM_ fileSizeQuota $ \quota -> do
    logInfo $ "Total / available storage: " <> tshow quota <> " / " <> tshow (quota - used)
    when (quota < used) $ logInfo "WARNING: storage quota is less than used storage, no files can be uploaded!"
-  tlsServerParams <- liftIO $ loadTLSServerParams caCertificateFile certificateFile privateKeyFile (alpn transportConfig)
+  tlsServerParams' <- liftIO $ loadTLSServerParams caCertificateFile certificateFile privateKeyFile
+  let TransportServerConfig {alpn} = transportConfig config
+  let tlsServerParams = case alpn of
+        Nothing -> tlsServerParams'
+        Just supported ->
+          tlsServerParams'
+            { T.serverHooks =
+                def
+                  { T.onALPNClientSuggest = Just $ pure . fromMaybe "" . find (`elem` supported)
+                  }
+            }
  Fingerprint fp <- liftIO $ loadFingerprint caCertificateFile
  serverStats <- atomically . newFileServerStats =<< liftIO getCurrentTime
  pure XFTPEnv {config, store, storeLog, random, tlsServerParams, serverIdentity = C.KeyHash fp, serverStats}
@@ -19,7 +19,7 @@ import Options.Applicative
 import Simplex.FileTransfer.Chunks
 import Simplex.FileTransfer.Description (FileSize (..))
 import Simplex.FileTransfer.Server (runXFTPServer)
-import Simplex.FileTransfer.Server.Env (XFTPServerConfig (..), defFileExpirationHours, defaultFileExpiration, defaultInactiveClientExpiration, supportedXFTPhandshakes)
+import Simplex.FileTransfer.Server.Env (XFTPServerConfig (..), defFileExpirationHours, defaultFileExpiration, defaultInactiveClientExpiration)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol (ProtoServerWithAuth (..), pattern XFTPServer)
@@ -180,8 +180,7 @@ xftpServerCLI cfgPath logPath = do
              serverStatsBackupFile = logStats $> combine logPath "file-server-stats.log",
              transportConfig =
                defaultTransportServerConfig
-                  { logTLSErrors = fromMaybe False $ iniOnOff "TRANSPORT" "log_tls_errors" ini,
-                    alpn = Just supportedXFTPhandshakes
+                  { logTLSErrors = fromMaybe False $ iniOnOff "TRANSPORT" "log_tls_errors" ini
                  }
            }

@@ -55,7 +55,6 @@ module Simplex.Messaging.Agent
    deleteConnectionAsync,
    deleteConnectionsAsync,
    createConnection,
-    prepareConnectionToJoin,
    joinConnection,
    allowConnection,
    acceptContact,
@@ -138,8 +137,6 @@ import qualified Data.List.NonEmpty as L
 import Data.Map.Strict (Map)
 import qualified Data.Map.Strict as M
 import Data.Maybe (catMaybes, fromMaybe, isJust, isNothing, mapMaybe)
-import Data.Set (Set)
-import qualified Data.Set as S
 import Data.Text (Text)
 import qualified Data.Text as T
 import Data.Time.Clock
@@ -152,7 +149,7 @@ import Simplex.FileTransfer.Protocol (FileParty (..))
 import Simplex.FileTransfer.Util (removePath)
 import Simplex.Messaging.Agent.Client
 import Simplex.Messaging.Agent.Env.SQLite
-import Simplex.Messaging.Agent.Lock (withLock, withLock')
+import Simplex.Messaging.Agent.Lock (withLock', withLock)
 import Simplex.Messaging.Agent.NtfSubSupervisor
 import Simplex.Messaging.Agent.Protocol
 import Simplex.Messaging.Agent.RetryInterval
@@ -163,7 +160,7 @@ import qualified Simplex.Messaging.Agent.Store.SQLite.Migrations as Migrations
 import Simplex.Messaging.Client (ProtocolClient (..), ServerTransmission)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Crypto.File (CryptoFile, CryptoFileArgs)
-import Simplex.Messaging.Crypto.Ratchet (PQEncryption, PQSupport (..), pattern PQEncOff, pattern PQEncOn, pattern PQSupportOff, pattern PQSupportOn)
+import Simplex.Messaging.Crypto.Ratchet (PQEncryption, PQSupport (..), pattern PQEncOn, pattern PQEncOff, pattern PQSupportOn, pattern PQSupportOff)
 import qualified Simplex.Messaging.Crypto.Ratchet as CR
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
@@ -201,7 +198,7 @@ getSMPAgentClient_ clientId cfg initServers store backgroundMode =
  liftIO $ newSMPAgentEnv cfg store >>= runReaderT runAgent
  where
    runAgent = do
-      c@AgentClient {acThread} <- atomically . newAgentClient clientId initServers =<< ask
+      c@AgentClient {acThread}  <- atomically . newAgentClient clientId initServers =<< ask
      t <- runAgentThreads c `forkFinally` const (liftIO $ disconnectAgentClient c)
      atomically . writeTVar acThread . Just =<< mkWeakThreadId t
      pure c
@@ -242,7 +239,7 @@ createUser c = withAgentEnv c .: createUser' c
 {-# INLINE createUser #-}

 -- | Delete user record optionally deleting all user's connections on SMP servers
-deleteUser :: AgentClient -> UserId -> Bool -> AE ()
+deleteUser :: AgentClient -> UserId -> Bool -> AE  ()
 deleteUser c = withAgentEnv c .: deleteUser' c
 {-# INLINE deleteUser #-}

@@ -291,18 +288,9 @@ createConnection :: AgentClient -> UserId -> Bool -> SConnectionMode c -> Maybe
 createConnection c userId enableNtfs = withAgentEnv c .:: newConn c userId "" enableNtfs
 {-# INLINE createConnection #-}

-- | Create SMP agent connection without queue (to be joined with joinConnection passing connection ID).
-- This method is required to prevent race condition when confirmation from peer is received before
-- the caller of joinConnection saves connection ID to the database.
-- Instead of it we could send confirmation asynchronously, but then it would be harder to report
-- "link deleted" (SMP AUTH) interactively, so this approach is simpler overall.
-prepareConnectionToJoin :: AgentClient -> UserId -> Bool -> ConnectionRequestUri c -> PQSupport -> AE ConnId
-prepareConnectionToJoin c userId enableNtfs = withAgentEnv c .: newConnToJoin c userId "" enableNtfs
-
-- | Join SMP agent connection (JOIN command).
-joinConnection :: AgentClient -> UserId -> Maybe ConnId -> Bool -> ConnectionRequestUri c -> ConnInfo -> PQSupport -> SubscriptionMode -> AE ConnId
-joinConnection c userId Nothing enableNtfs = withAgentEnv c .:: joinConn c userId "" False enableNtfs
-joinConnection c userId (Just connId) enableNtfs = withAgentEnv c .:: joinConn c userId connId True enableNtfs
+-- | Join SMP agent connection (JOIN command)
+joinConnection :: AgentClient -> UserId -> Bool -> ConnectionRequestUri c -> ConnInfo -> PQSupport -> SubscriptionMode -> AE ConnId
+joinConnection c userId enableNtfs = withAgentEnv c .:: joinConn c userId "" enableNtfs
 {-# INLINE joinConnection #-}

 -- | Allow connection to continue after CONF notification (LET command)
@@ -356,12 +344,12 @@ sendMessage c = withAgentEnv c .:: sendMessage' c
 type MsgReq = (ConnId, PQEncryption, MsgFlags, MsgBody)

 -- | Send multiple messages to different connections (SEND command)
-sendMessages :: AgentClient -> [MsgReq] -> AE [Either AgentErrorType (AgentMsgId, PQEncryption)]
-sendMessages c = withAgentEnv c . sendMessages' c
+sendMessages :: AgentClient -> [MsgReq] -> IO [Either AgentErrorType (AgentMsgId, PQEncryption)]
+sendMessages c = withAgentEnv' c . sendMessages' c
 {-# INLINE sendMessages #-}

-sendMessagesB :: Traversable t => AgentClient -> t (Either AgentErrorType MsgReq) -> AE (t (Either AgentErrorType (AgentMsgId, PQEncryption)))
-sendMessagesB c = withAgentEnv c . sendMessagesB' c
+sendMessagesB :: Traversable t => AgentClient -> t (Either AgentErrorType MsgReq) -> IO (t (Either AgentErrorType (AgentMsgId, PQEncryption)))
+sendMessagesB c = withAgentEnv' c . sendMessagesB' c
 {-# INLINE sendMessagesB #-}

 ackMessage :: AgentClient -> ConnId -> AgentMsgId -> Maybe MsgReceiptInfo -> AE ()
@@ -431,21 +419,22 @@ getNetworkConfig = fmap snd . readTVarIO . useNetworkConfig
 {-# INLINE getNetworkConfig #-}

 setUserNetworkInfo :: AgentClient -> UserNetworkInfo -> IO ()
-setUserNetworkInfo c@AgentClient {userNetworkInfo, userNetworkUpdated} ni = withAgentEnv' c $ do
-  ts' <- liftIO getCurrentTime
-  i <- asks $ userOfflineDelay . config
-  -- if network offline event happens in less than `userOfflineDelay` after the previous event, it is ignored
-  atomically . whenM ((isOnline ni ||) <$> notRecentlyChanged ts' i) $ do
-    writeTVar userNetworkInfo ni
-    writeTVar userNetworkUpdated $ Just ts'
-  where
-    notRecentlyChanged ts' i =
-      maybe True (\ts -> diffUTCTime ts' ts > i) <$> readTVar userNetworkUpdated
+setUserNetworkInfo c@AgentClient {userNetworkState} UserNetworkInfo {networkType = nt', online} = withAgentEnv' c $ do
+  d <- asks $ initialInterval . userNetworkInterval . config
+  ts <- liftIO getCurrentTime
+  atomically $ do
+    ns@UserNetworkState {networkType = nt, offline} <- readTVar userNetworkState
+    when (nt' /= nt || online /= isNothing offline) $
+      writeTVar userNetworkState $!
+        let offline'
+              | nt' /= UNNone && online = Nothing
+              | isJust offline = offline
+              | otherwise = Just UNSOffline {offlineDelay = d, offlineFrom = ts}
+         in ns {networkType = nt', offline = offline'}

 reconnectAllServers :: AgentClient -> IO ()
 reconnectAllServers c = do
  reconnectServerClients c smpClients
-  reconnectServerClients c xftpClients
  reconnectServerClients c ntfClients

 -- | Register device notifications token
@@ -586,7 +575,7 @@ processCommand :: AgentClient -> (EntityId, APartyCmd 'Client) -> AM (EntityId,
 processCommand c (connId, APC e cmd) =
  second (APC e) <$> case cmd of
    NEW enableNtfs (ACM cMode) pqIK subMode -> second (INV . ACR cMode) <$> newConn c userId connId enableNtfs cMode Nothing pqIK subMode
-    JOIN enableNtfs (ACR _ cReq) pqEnc subMode connInfo -> (,OK) <$> joinConn c userId connId False enableNtfs cReq connInfo pqEnc subMode
+    JOIN enableNtfs (ACR _ cReq) pqEnc subMode connInfo -> (,OK) <$> joinConn c userId connId enableNtfs cReq connInfo pqEnc subMode
    LET confId ownCInfo -> allowConnection' c connId confId ownCInfo $> (connId, OK)
    ACPT invId pqEnc ownCInfo -> (,OK) <$> acceptContact' c connId True invId ownCInfo pqEnc SMSubscribe
    RJCT invId -> rejectContact' c connId invId $> (connId, OK)
@@ -629,14 +618,14 @@ newConnAsync c userId corrId enableNtfs cMode pqInitKeys subMode = do
 newConnNoQueues :: AgentClient -> UserId -> ConnId -> Bool -> SConnectionMode c -> PQSupport -> AM ConnId
 newConnNoQueues c userId connId enableNtfs cMode pqSupport = do
  g <- asks random
-  connAgentVersion <- asks $ maxVersion . smpAgentVRange . config
+  connAgentVersion <- asks $ maxVersion . ($ pqSupport) . smpAgentVRange . config
  let cData = ConnData {userId, connId, connAgentVersion, enableNtfs, lastExternalSndId = 0, deleted = False, ratchetSyncState = RSOk, pqSupport}
  withStore c $ \db -> createNewConn db g cData cMode

 joinConnAsync :: AgentClient -> UserId -> ACorrId -> Bool -> ConnectionRequestUri c -> ConnInfo -> PQSupport -> SubscriptionMode -> AM ConnId
 joinConnAsync c userId corrId enableNtfs cReqUri@CRInvitationUri {} cInfo pqSup subMode = do
  withInvLock c (strEncode cReqUri) "joinConnAsync" $ do
-    lift (compatibleInvitationUri cReqUri) >>= \case
+    lift (compatibleInvitationUri cReqUri pqSup) >>= \case
      Just (_, Compatible (CR.E2ERatchetParams v _ _ _), Compatible connAgentVersion) -> do
        g <- asks random
        let pqSupport = pqSup `CR.pqSupportAnd` versionPQSupport_ connAgentVersion (Just v)
@@ -719,14 +708,11 @@ switchConnectionAsync' c corrId connId =

 newConn :: AgentClient -> UserId -> ConnId -> Bool -> SConnectionMode c -> Maybe CRClientData -> CR.InitialKeys -> SubscriptionMode -> AM (ConnId, ConnectionRequestUri c)
 newConn c userId connId enableNtfs cMode clientData pqInitKeys subMode =
-  getSMPServer c userId >>= newConnSrv c userId connId False enableNtfs cMode clientData pqInitKeys subMode
+  getSMPServer c userId >>= newConnSrv c userId connId enableNtfs cMode clientData pqInitKeys subMode

-newConnSrv :: AgentClient -> UserId -> ConnId -> Bool -> Bool -> SConnectionMode c -> Maybe CRClientData -> CR.InitialKeys -> SubscriptionMode -> SMPServerWithAuth -> AM (ConnId, ConnectionRequestUri c)
-newConnSrv c userId connId hasNewConn enableNtfs cMode clientData pqInitKeys subMode srv = do
-  connId' <-
-    if hasNewConn
-      then pure connId
-      else newConnNoQueues c userId connId enableNtfs cMode (CR.connPQEncryption pqInitKeys)
+newConnSrv :: AgentClient -> UserId -> ConnId -> Bool -> SConnectionMode c -> Maybe CRClientData -> CR.InitialKeys -> SubscriptionMode -> SMPServerWithAuth -> AM (ConnId, ConnectionRequestUri c)
+newConnSrv c userId connId enableNtfs cMode clientData pqInitKeys subMode srv = do
+  connId' <- newConnNoQueues c userId connId enableNtfs cMode (CR.connPQEncryption pqInitKeys)
  newRcvConnSrv c userId connId' enableNtfs cMode clientData pqInitKeys subMode srv

 newRcvConnSrv :: AgentClient -> UserId -> ConnId -> Bool -> SConnectionMode c -> Maybe CRClientData -> CR.InitialKeys -> SubscriptionMode -> SMPServerWithAuth -> AM (ConnId, ConnectionRequestUri c)
@@ -743,118 +729,99 @@ newRcvConnSrv c userId connId enableNtfs cMode clientData pqInitKeys subMode srv
  when enableNtfs $ do
    ns <- asks ntfSupervisor
    atomically $ sendNtfSubCommand ns (connId, NSCCreate)
-  let crData = ConnReqUriData SSSimplex smpAgentVRange [qUri] clientData
+  let pqEnc = CR.connPQEncryption pqInitKeys
+      crData = ConnReqUriData SSSimplex (smpAgentVRange pqEnc) [qUri] clientData
+      e2eVRange = e2eEncryptVRange pqEnc
  case cMode of
    SCMContact -> pure (connId, CRContactUri crData)
    SCMInvitation -> do
      g <- asks random
-      (pk1, pk2, pKem, e2eRcvParams) <- liftIO $ CR.generateRcvE2EParams g (maxVersion e2eEncryptVRange) (CR.initialPQEncryption pqInitKeys)
+      (pk1, pk2, pKem, e2eRcvParams) <- liftIO $ CR.generateRcvE2EParams g (maxVersion e2eVRange) (CR.initialPQEncryption pqInitKeys)
      withStore' c $ \db -> createRatchetX3dhKeys db connId pk1 pk2 pKem
-      pure (connId, CRInvitationUri crData $ toVersionRangeT e2eRcvParams e2eEncryptVRange)
+      pure (connId, CRInvitationUri crData $ toVersionRangeT e2eRcvParams e2eVRange)

-newConnToJoin :: forall c. AgentClient -> UserId -> ConnId -> Bool -> ConnectionRequestUri c -> PQSupport -> AM ConnId
-newConnToJoin c userId connId enableNtfs cReq pqSup = case cReq of
-  CRInvitationUri {} ->
-    lift (compatibleInvitationUri cReq) >>= \case
-      Just (_, (Compatible (CR.E2ERatchetParams v _ _ _)), aVersion) -> create aVersion (Just v)
-      Nothing -> throwError $ AGENT A_VERSION
-  CRContactUri {} ->
-    lift (compatibleContactUri cReq) >>= \case
-      Just (_, aVersion) -> create aVersion Nothing
-      Nothing -> throwError $ AGENT A_VERSION
-  where
-    create :: Compatible VersionSMPA -> Maybe CR.VersionE2E -> AM ConnId
-    create (Compatible connAgentVersion) e2eV_ = do
-      g <- asks random
-      let pqSupport = pqSup `CR.pqSupportAnd` versionPQSupport_ connAgentVersion e2eV_
-          cData = ConnData {userId, connId, connAgentVersion, enableNtfs, lastExternalSndId = 0, deleted = False, ratchetSyncState = RSOk, pqSupport}
-      withStore c $ \db -> createNewConn db g cData SCMInvitation
-
-joinConn :: AgentClient -> UserId -> ConnId -> Bool -> Bool -> ConnectionRequestUri c -> ConnInfo -> PQSupport -> SubscriptionMode -> AM ConnId
-joinConn c userId connId hasNewConn enableNtfs cReq cInfo pqSupport subMode = do
+joinConn :: AgentClient -> UserId -> ConnId -> Bool -> ConnectionRequestUri c -> ConnInfo -> PQSupport -> SubscriptionMode -> AM ConnId
+joinConn c userId connId enableNtfs cReq cInfo pqSupport subMode = do
  srv <- case cReq of
    CRInvitationUri ConnReqUriData {crSmpQueues = q :| _} _ ->
      getNextServer c userId [qServer q]
    _ -> getSMPServer c userId
-  joinConnSrv c userId connId hasNewConn enableNtfs cReq cInfo pqSupport subMode srv
+  joinConnSrv c userId connId enableNtfs cReq cInfo pqSupport subMode srv

-startJoinInvitation :: UserId -> ConnId -> Bool -> ConnectionRequestUri 'CMInvitation -> PQSupport -> AM (ConnData, NewSndQueue, CR.Ratchet 'C.X448, CR.SndE2ERatchetParams 'C.X448)
+startJoinInvitation :: UserId -> ConnId -> Bool -> ConnectionRequestUri 'CMInvitation -> PQSupport -> AM (Compatible VersionSMPA, ConnData, NewSndQueue, CR.Ratchet 'C.X448, CR.SndE2ERatchetParams 'C.X448)
 startJoinInvitation userId connId enableNtfs cReqUri pqSup =
-  lift (compatibleInvitationUri cReqUri) >>= \case
-    Just (qInfo, (Compatible e2eRcvParams@(CR.E2ERatchetParams v _ rcDHRr kem_)), Compatible connAgentVersion) -> do
+  lift (compatibleInvitationUri cReqUri pqSup) >>= \case
+    Just (qInfo, (Compatible e2eRcvParams@(CR.E2ERatchetParams v _ rcDHRr kem_)), aVersion@(Compatible connAgentVersion)) -> do
      g <- asks random
      let pqSupport = pqSup `CR.pqSupportAnd` versionPQSupport_ connAgentVersion (Just v)
      (pk1, pk2, pKem, e2eSndParams) <- liftIO $ CR.generateSndE2EParams g v (CR.replyKEM_ v kem_ pqSupport)
      (_, rcDHRs) <- atomically $ C.generateKeyPair g
      rcParams <- liftEitherWith cryptoError $ CR.pqX3dhSnd pk1 pk2 pKem e2eRcvParams
-      maxSupported <- asks $ maxVersion . e2eEncryptVRange . config
+      maxSupported <- asks $ maxVersion . ($ pqSup) . e2eEncryptVRange . config
      let rcVs = CR.RatchetVersions {current = v, maxSupported}
          rc = CR.initSndRatchet rcVs rcDHRr rcDHRs rcParams
      q <- lift $ newSndQueue userId "" qInfo
      let cData = ConnData {userId, connId, connAgentVersion, enableNtfs, lastExternalSndId = 0, deleted = False, ratchetSyncState = RSOk, pqSupport}
-      pure (cData, q, rc, e2eSndParams)
+      pure (aVersion, cData, q, rc, e2eSndParams)
    Nothing -> throwError $ AGENT A_VERSION

 connRequestPQSupport :: AgentClient -> PQSupport -> ConnectionRequestUri c -> IO (Maybe (VersionSMPA, PQSupport))
 connRequestPQSupport c pqSup cReq = withAgentEnv' c $ case cReq of
-  CRInvitationUri {} -> invPQSupported <$$> compatibleInvitationUri cReq
+  CRInvitationUri {} -> invPQSupported <$$> compatibleInvitationUri cReq pqSup
    where
      invPQSupported (_, Compatible (CR.E2ERatchetParams e2eV _ _ _), Compatible agentV) = (agentV, pqSup `CR.pqSupportAnd` versionPQSupport_ agentV (Just e2eV))
-  CRContactUri {} -> ctPQSupported <$$> compatibleContactUri cReq
+  CRContactUri {} -> ctPQSupported <$$> compatibleContactUri cReq pqSup
    where
      ctPQSupported (_, Compatible agentV) = (agentV, pqSup `CR.pqSupportAnd` versionPQSupport_ agentV Nothing)

-compatibleInvitationUri :: ConnectionRequestUri 'CMInvitation -> AM' (Maybe (Compatible SMPQueueInfo, Compatible (CR.RcvE2ERatchetParams 'C.X448), Compatible VersionSMPA))
-compatibleInvitationUri (CRInvitationUri ConnReqUriData {crAgentVRange, crSmpQueues = (qUri :| _)} e2eRcvParamsUri) = do
+compatibleInvitationUri :: ConnectionRequestUri 'CMInvitation -> PQSupport -> AM' (Maybe (Compatible SMPQueueInfo, Compatible (CR.RcvE2ERatchetParams 'C.X448), Compatible VersionSMPA))
+compatibleInvitationUri (CRInvitationUri ConnReqUriData {crAgentVRange, crSmpQueues = (qUri :| _)} e2eRcvParamsUri) pqSup = do
  AgentConfig {smpClientVRange, smpAgentVRange, e2eEncryptVRange} <- asks config
  pure $
    (,,)
      <$> (qUri `compatibleVersion` smpClientVRange)
-      <*> (e2eRcvParamsUri `compatibleVersion` e2eEncryptVRange)
-      <*> (crAgentVRange `compatibleVersion` smpAgentVRange)
+      <*> (e2eRcvParamsUri `compatibleVersion` e2eEncryptVRange pqSup)
+      <*> (crAgentVRange `compatibleVersion` smpAgentVRange pqSup)

-compatibleContactUri :: ConnectionRequestUri 'CMContact -> AM' (Maybe (Compatible SMPQueueInfo, Compatible VersionSMPA))
-compatibleContactUri (CRContactUri ConnReqUriData {crAgentVRange, crSmpQueues = (qUri :| _)}) = do
+compatibleContactUri :: ConnectionRequestUri 'CMContact -> PQSupport -> AM' (Maybe (Compatible SMPQueueInfo, Compatible VersionSMPA))
+compatibleContactUri (CRContactUri ConnReqUriData {crAgentVRange, crSmpQueues = (qUri :| _)}) pqSup = do
  AgentConfig {smpClientVRange, smpAgentVRange} <- asks config
  pure $
    (,)
      <$> (qUri `compatibleVersion` smpClientVRange)
-      <*> (crAgentVRange `compatibleVersion` smpAgentVRange)
+      <*> (crAgentVRange `compatibleVersion` smpAgentVRange pqSup)

 versionPQSupport_ :: VersionSMPA -> Maybe CR.VersionE2E -> PQSupport
 versionPQSupport_ agentV e2eV_ = PQSupport $ agentV >= pqdrSMPAgentVersion && maybe True (>= CR.pqRatchetE2EEncryptVersion) e2eV_
 {-# INLINE versionPQSupport_ #-}

-joinConnSrv :: AgentClient -> UserId -> ConnId -> Bool -> Bool -> ConnectionRequestUri c -> ConnInfo -> PQSupport -> SubscriptionMode -> SMPServerWithAuth -> AM ConnId
-joinConnSrv c userId connId hasNewConn enableNtfs inv@CRInvitationUri {} cInfo pqSup subMode srv =
+joinConnSrv :: AgentClient -> UserId -> ConnId -> Bool -> ConnectionRequestUri c -> ConnInfo -> PQSupport -> SubscriptionMode -> SMPServerWithAuth -> AM ConnId
+joinConnSrv c userId connId enableNtfs inv@CRInvitationUri {} cInfo pqSup subMode srv =
  withInvLock c (strEncode inv) "joinConnSrv" $ do
-    (cData, q, rc, e2eSndParams) <- startJoinInvitation userId connId enableNtfs inv pqSup
+    (aVersion, cData, q, rc, e2eSndParams) <- startJoinInvitation userId connId enableNtfs inv pqSup
    g <- asks random
    (connId', sq) <- withStore c $ \db -> runExceptT $ do
-      r@(connId', _) <-
-        if hasNewConn
-          then (connId,) <$> ExceptT (updateNewConnSnd db connId q)
-          else ExceptT $ createSndConn db g cData q
+      r@(connId', _) <- ExceptT $ createSndConn db g cData q
      liftIO $ createRatchet db connId' rc
      pure r
    let cData' = (cData :: ConnData) {connId = connId'}
-    tryError (confirmQueue c cData' sq srv cInfo (Just e2eSndParams) subMode) >>= \case
+    tryError (confirmQueue aVersion c cData' sq srv cInfo (Just e2eSndParams) subMode) >>= \case
      Right _ -> pure connId'
      Left e -> do
        -- possible improvement: recovery for failure on network timeout, see rfcs/2022-04-20-smp-conf-timeout-recovery.md
        void $ withStore' c $ \db -> deleteConn db Nothing connId'
        throwError e
-joinConnSrv c userId connId hasNewConn enableNtfs cReqUri@CRContactUri {} cInfo pqSup subMode srv =
-  lift (compatibleContactUri cReqUri) >>= \case
+joinConnSrv c userId connId enableNtfs cReqUri@CRContactUri {} cInfo pqSup subMode srv =
+  lift (compatibleContactUri cReqUri pqSup) >>= \case
    Just (qInfo, vrsn) -> do
-      (connId', cReq) <- newConnSrv c userId connId hasNewConn enableNtfs SCMInvitation Nothing (CR.IKNoPQ pqSup) subMode srv
+      (connId', cReq) <- newConnSrv c userId connId enableNtfs SCMInvitation Nothing (CR.IKNoPQ pqSup) subMode srv
      sendInvitation c userId qInfo vrsn cReq cInfo
      pure connId'
    Nothing -> throwError $ AGENT A_VERSION

 joinConnSrvAsync :: AgentClient -> UserId -> ConnId -> Bool -> ConnectionRequestUri c -> ConnInfo -> PQSupport -> SubscriptionMode -> SMPServerWithAuth -> AM ()
 joinConnSrvAsync c userId connId enableNtfs inv@CRInvitationUri {} cInfo pqSupport subMode srv = do
-  (cData, q, rc, e2eSndParams) <- startJoinInvitation userId connId enableNtfs inv pqSupport
+  (_aVersion, cData, q, rc, e2eSndParams) <- startJoinInvitation userId connId enableNtfs inv pqSupport
  q' <- withStore c $ \db -> runExceptT $ do
    liftIO $ createRatchet db connId rc
    ExceptT $ updateNewConnSnd db connId q
@@ -896,7 +863,7 @@ acceptContact' c connId enableNtfs invId ownConnInfo pqSupport subMode = withCon
  withStore c (`getConn` contactConnId) >>= \case
    SomeConn _ (ContactConnection ConnData {userId} _) -> do
      withStore' c $ \db -> acceptInvitation db invId ownConnInfo
-      joinConn c userId connId False enableNtfs connReq ownConnInfo pqSupport subMode `catchAgentError` \err -> do
+      joinConn c userId connId enableNtfs connReq ownConnInfo pqSupport subMode `catchAgentError` \err -> do
        withStore' c (`unacceptInvitation` invId)
        throwError err
    _ -> throwError $ CMD PROHIBITED
@@ -1035,27 +1002,16 @@ getNotificationMessage' c nonce encNtfInfo = do

 -- | Send message to the connection (SEND command) in Reader monad
 sendMessage' :: AgentClient -> ConnId -> PQEncryption -> MsgFlags -> MsgBody -> AM (AgentMsgId, PQEncryption)
-sendMessage' c connId pqEnc msgFlags msg = ExceptT $ runIdentity <$> sendMessagesB_ c (Identity (Right (connId, pqEnc, msgFlags, msg))) (S.singleton connId)
+sendMessage' c connId pqEnc msgFlags msg = ExceptT $ runIdentity <$> sendMessagesB' c (Identity (Right (connId, pqEnc, msgFlags, msg)))
 {-# INLINE sendMessage' #-}

 -- | Send multiple messages to different connections (SEND command) in Reader monad
-sendMessages' :: AgentClient -> [MsgReq] -> AM [Either AgentErrorType (AgentMsgId, PQEncryption)]
+sendMessages' :: AgentClient -> [MsgReq] -> AM' [Either AgentErrorType (AgentMsgId, PQEncryption)]
 sendMessages' c = sendMessagesB' c . map Right
 {-# INLINE sendMessages' #-}

-sendMessagesB' :: forall t. Traversable t => AgentClient -> t (Either AgentErrorType MsgReq) -> AM (t (Either AgentErrorType (AgentMsgId, PQEncryption)))
-sendMessagesB' c reqs = do
-  connIds <- liftEither $ foldl' addConnId (Right S.empty) reqs
-  lift $ sendMessagesB_ c reqs connIds
-  where
-    addConnId s@(Right s') (Right (connId, _, _, _))
-      | B.null connId = s
-      | connId `S.notMember` s' = Right $ S.insert connId s'
-      | otherwise = Left $ INTERNAL "sendMessages: duplicate connection ID"
-    addConnId s _ = s
-
-sendMessagesB_ :: forall t. Traversable t => AgentClient -> t (Either AgentErrorType MsgReq) -> Set ConnId -> AM' (t (Either AgentErrorType (AgentMsgId, PQEncryption)))
-sendMessagesB_ c reqs connIds = withConnLocks c connIds "sendMessages" $ do
+sendMessagesB' :: forall t. Traversable t => AgentClient -> t (Either AgentErrorType MsgReq) -> AM' (t (Either AgentErrorType (AgentMsgId, PQEncryption)))
+sendMessagesB' c reqs = withConnLocks c connIds "sendMessages" $ do
  reqs' <- withStoreBatch c (\db -> fmap (bindRight $ \req@(connId, _, _, _) -> bimap storeError (req,) <$> getConn db connId) reqs)
  let (toEnable, reqs'') = mapAccumL prepareConn [] reqs'
  void $ withStoreBatch' c $ \db -> map (\connId -> setConnPQSupport db connId PQSupportOn) toEnable
@@ -1077,6 +1033,7 @@ sendMessagesB_ c reqs connIds = withConnLocks c connIds "sendMessages" $ do
              let cData' = cData {pqSupport = PQSupportOn} :: ConnData
               in (connId : acc, Right (cData', sqs, Just pqEnc, msgFlags, A_MSG msg))
          | otherwise = (acc, Right (cData, sqs, Just pqEnc, msgFlags, A_MSG msg))
+    connIds = map (\(connId, _, _, _) -> connId) $ rights $ toList reqs

 -- / async command processing v v v

@@ -1252,7 +1209,7 @@ enqueueMessage c cData sq msgFlags aMessage =
 {-# INLINE enqueueMessage #-}

 -- this function is used only for sending messages in batch, it returns the list of successes to enqueue additional deliveries
-enqueueMessageB :: forall t. Traversable t => AgentClient -> t (Either AgentErrorType (ConnData, NonEmpty SndQueue, Maybe PQEncryption, MsgFlags, AMessage)) -> AM' (t (Either AgentErrorType ((AgentMsgId, PQEncryption), Maybe (ConnData, [SndQueue], AgentMsgId))))
+enqueueMessageB :: forall t. (Traversable t) => AgentClient -> t (Either AgentErrorType (ConnData, NonEmpty SndQueue, Maybe PQEncryption, MsgFlags, AMessage)) -> AM' (t (Either AgentErrorType ((AgentMsgId, PQEncryption), Maybe (ConnData, [SndQueue], AgentMsgId))))
 enqueueMessageB c reqs = do
  cfg <- asks config
  reqMids <- withStoreBatch c $ \db -> fmap (bindRight $ storeSentMsg db cfg) reqs
@@ -1262,7 +1219,7 @@ enqueueMessageB c reqs = do
    pure $ Right ((msgId, pqSecr), if null sqs' then Nothing else Just (cData, sqs', msgId))
  where
    storeSentMsg :: DB.Connection -> AgentConfig -> (ConnData, NonEmpty SndQueue, Maybe PQEncryption, MsgFlags, AMessage) -> IO (Either AgentErrorType ((ConnData, NonEmpty SndQueue, Maybe PQEncryption, MsgFlags, AMessage), InternalId, PQEncryption))
-    storeSentMsg db cfg req@(cData@ConnData {connId}, sq :| _, pqEnc_, msgFlags, aMessage) = fmap (first storeError) $ runExceptT $ do
+    storeSentMsg db cfg req@(cData@ConnData {connId, pqSupport}, sq :| _, pqEnc_, msgFlags, aMessage) = fmap (first storeError) $ runExceptT $ do
      let AgentConfig {smpAgentVRange, e2eEncryptVRange} = cfg
      internalTs <- liftIO getCurrentTime
      (internalId, internalSndId, prevMsgHash) <- liftIO $ updateSndIds db connId
@@ -1270,9 +1227,10 @@ enqueueMessageB c reqs = do
          agentMsg = AgentMessage privHeader aMessage
          agentMsgStr = smpEncode agentMsg
          internalHash = C.sha256Hash agentMsgStr
-          currentE2EVersion = maxVersion e2eEncryptVRange
-      (encAgentMessage, pqEnc) <- agentRatchetEncrypt db cData agentMsgStr e2eEncAgentMsgLength pqEnc_ currentE2EVersion
-      let agentVersion = maxVersion smpAgentVRange
+          currentE2EVersion = maxVersion $ e2eEncryptVRange PQSupportOff
+      (encAgentMessage, pqEnc) <- agentRatchetEncrypt db cData agentMsgStr e2eEncUserMsgLength pqEnc_ currentE2EVersion
+      -- agent version range is determined by the connection suppport of PQ encryption, that is may be enabled when message is sent
+      let agentVersion = maxVersion $ smpAgentVRange pqSupport
          msgBody = smpEncode $ AgentMsgEnvelope {agentVersion, encAgentMessage}
          msgType = agentMessageType agentMsg
          msgData = SndMsgData {internalId, internalSndId, internalTs, msgType, msgFlags, msgBody, pqEncryption = pqEnc, internalHash, prevMsgHash}
@@ -1284,7 +1242,7 @@ enqueueSavedMessage :: AgentClient -> ConnData -> AgentMsgId -> SndQueue -> AM'
 enqueueSavedMessage c cData msgId sq = enqueueSavedMessageB c $ Identity (cData, [sq], msgId)
 {-# INLINE enqueueSavedMessage #-}

-enqueueSavedMessageB :: Foldable t => AgentClient -> t (ConnData, [SndQueue], AgentMsgId) -> AM' ()
+enqueueSavedMessageB :: (Foldable t) => AgentClient -> t (ConnData, [SndQueue], AgentMsgId) -> AM' ()
 enqueueSavedMessageB c reqs = do
  -- saving to the database is in the start to avoid race conditions when delivery is read from queue before it is saved
  void $ withStoreBatch' c $ \db -> concatMap (storeDeliveries db) reqs
@@ -1328,7 +1286,7 @@ runSmpQueueMsgDelivery c@AgentClient {subQ} ConnData {connId} sq (Worker {doWork
        let mId = unId msgId
            ri' = maybe id updateRetryInterval2 msgRetryState ri
        withRetryLock2 ri' qLock $ \riState loop -> do
-          liftIO $ waitForUserNetwork c
+          lift $ waitForUserNetwork c
          resp <- tryError $ case msgType of
            AM_CONN_INFO -> sendConfirmation c sq msgBody
            AM_CONN_INFO_REPLY -> sendConfirmation c sq msgBody
@@ -1562,7 +1520,7 @@ synchronizeRatchet' c connId pqSupport' force = withConnLock c connId "synchroni
          let cData' = cData {pqSupport = pqSupport'} :: ConnData
          AgentConfig {e2eEncryptVRange} <- asks config
          g <- asks random
-          (pk1, pk2, pKem, e2eParams) <- liftIO $ CR.generateRcvE2EParams g (maxVersion e2eEncryptVRange) pqSupport'
+          (pk1, pk2, pKem, e2eParams) <- liftIO $ CR.generateRcvE2EParams g (maxVersion $ e2eEncryptVRange pqSupport') pqSupport'
          enqueueRatchetKeyMsgs c cData' sqs e2eParams
          withStore' c $ \db -> do
            setConnRatchetSync db connId RSStarted
@@ -2088,7 +2046,7 @@ data ACKd = ACKd | ACKPending
 -- | make sure to ACK or throw in each message processing branch
 -- it cannot be finally, unfortunately, as sometimes it needs to be ACK+DEL
 processSMPTransmission :: AgentClient -> ServerTransmission SMPVersion BrokerMsg -> AM ()
-processSMPTransmission c@AgentClient {smpClients, subQ} (tSess@(_, srv, _), _v, sessId, isResponse, rId, cmd) = do
+processSMPTransmission c@AgentClient {smpClients, subQ} (tSess@(_, srv, _), _v, sessId, rId, cmd) = do
  (rq, SomeConn _ conn) <- withStore c (\db -> getRcvConn db srv rId)
  processSMP rq conn $ toConnData conn
  where
@@ -2231,8 +2189,8 @@ processSMPTransmission c@AgentClient {smpClients, subQ} (tSess@(_, srv, _), _v,
                      _ -> prohibited >> ack
                  _ -> prohibited >> ack
              updateConnVersion :: Connection c -> ConnData -> VersionSMPA -> AM (Connection c)
-              updateConnVersion conn' cData' msgAgentVersion = do
-                aVRange <- asks $ smpAgentVRange . config
+              updateConnVersion conn' cData'@ConnData {pqSupport} msgAgentVersion = do
+                aVRange <- asks $ ($ pqSupport) . smpAgentVRange . config
                let msgAVRange = fromMaybe (versionToRange msgAgentVersion) $ safeVersionRange (minVersion aVRange) msgAgentVersion
                case msgAVRange `compatibleVersion` aVRange of
                  Just (Compatible av)
@@ -2263,7 +2221,7 @@ processSMPTransmission c@AgentClient {smpClients, subQ} (tSess@(_, srv, _), _v,
              ignored = pure "END from disconnected client - ignored"
          _ -> do
            logServer "<--" c srv rId $ "unexpected: " <> bshow cmd
-            notify . ERR $ BROKER (B.unpack $ strEncode srv) $ if isResponse then TIMEOUT else UNEXPECTED
+            notify . ERR $ BROKER (B.unpack $ strEncode srv) UNEXPECTED
        where
          notify :: forall e m. MonadIO m => AEntityI e => ACommand 'Agent e -> m ()
          notify = atomically . notify'
@@ -2298,17 +2256,19 @@ processSMPTransmission c@AgentClient {smpClients, subQ} (tSess@(_, srv, _), _v,
            logServer "<--" c srv rId $ "MSG <CONF>:" <> logSecret srvMsgId
            AgentConfig {smpClientVRange, smpAgentVRange, e2eEncryptVRange} <- asks config
            let ConnData {pqSupport} = toConnData conn'
+                aVRange = smpAgentVRange pqSupport
+                e2eVRange = e2eEncryptVRange pqSupport
            unless
-              (agentVersion `isCompatible` smpAgentVRange && smpClientVersion `isCompatible` smpClientVRange)
+              (agentVersion `isCompatible` aVRange && smpClientVersion `isCompatible` smpClientVRange)
              (throwError $ AGENT A_VERSION)
            case status of
              New -> case (conn', e2eEncryption) of
                -- party initiating connection
                (RcvConnection _ _, Just (CR.AE2ERatchetParams _ e2eSndParams@(CR.E2ERatchetParams e2eVersion _ _ _))) -> do
-                  unless (e2eVersion `isCompatible` e2eEncryptVRange) (throwError $ AGENT A_VERSION)
+                  unless (e2eVersion `isCompatible` e2eVRange) (throwError $ AGENT A_VERSION)
                  (pk1, rcDHRs, pKem) <- withStore c (`getRatchetX3dhKeys` connId)
                  rcParams <- liftError cryptoError $ CR.pqX3dhRcv pk1 rcDHRs pKem e2eSndParams
-                  let rcVs = CR.RatchetVersions {current = e2eVersion, maxSupported = maxVersion e2eEncryptVRange}
+                  let rcVs = CR.RatchetVersions {current = e2eVersion, maxSupported = maxVersion e2eVRange}
                      pqSupport' = pqSupport `CR.pqSupportAnd` versionPQSupport_ agentVersion (Just e2eVersion)
                      rc = CR.initRcvRatchet rcVs rcDHRs rcParams pqSupport'
                  g <- asks random
@@ -2490,7 +2450,7 @@ processSMPTransmission c@AgentClient {smpClients, subQ} (tSess@(_, srv, _), _v,
              ContactConnection {} -> do
                -- show connection request even if invitaion via contact address is not compatible.
                -- in case invitation not compatible, assume there is no PQ encryption support.
-                pqSupport <- lift $ maybe PQSupportOff pqSupported <$> compatibleInvitationUri connReq
+                pqSupport <- lift $ maybe PQSupportOff pqSupported <$> compatibleInvitationUri connReq PQSupportOn
                g <- asks random
                let newInv = NewInvitation {contactConnId = connId, connReq, recipientConnInfo = cInfo}
                invId <- withStore c $ \db -> createInvitation db g newInv
@@ -2510,9 +2470,10 @@ processSMPTransmission c@AgentClient {smpClients, subQ} (tSess@(_, srv, _), _v,
          newRatchetKey e2eOtherPartyParams@(CR.E2ERatchetParams e2eVersion k1Rcv k2Rcv _) conn'@(DuplexConnection cData'@ConnData {lastExternalSndId, pqSupport} _ sqs) =
            unlessM ratchetExists $ do
              AgentConfig {e2eEncryptVRange} <- asks config
-              unless (e2eVersion `isCompatible` e2eEncryptVRange) (throwError $ AGENT A_VERSION)
+              let connE2EVRange = e2eEncryptVRange pqSupport
+              unless (e2eVersion `isCompatible` connE2EVRange) (throwError $ AGENT A_VERSION)
              keys <- getSendRatchetKeys
-              let rcVs = CR.RatchetVersions {current = e2eVersion, maxSupported = maxVersion e2eEncryptVRange}
+              let rcVs = CR.RatchetVersions {current = e2eVersion, maxSupported = maxVersion connE2EVRange}
              initRatchet rcVs keys
              notifyAgreed
            where
@@ -2610,20 +2571,21 @@ confirmQueueAsync c cData sq srv connInfo e2eEncryption_ subMode = do
  storeConfirmation c cData sq e2eEncryption_ =<< mkAgentConfirmation c cData sq srv connInfo subMode
  lift $ submitPendingMsg c cData sq

-confirmQueue :: AgentClient -> ConnData -> SndQueue -> SMPServerWithAuth -> ConnInfo -> Maybe (CR.SndE2ERatchetParams 'C.X448) -> SubscriptionMode -> AM ()
-confirmQueue c cData@ConnData {connId, connAgentVersion, pqSupport} sq srv connInfo e2eEncryption_ subMode = do
+confirmQueue :: Compatible VersionSMPA -> AgentClient -> ConnData -> SndQueue -> SMPServerWithAuth -> ConnInfo -> Maybe (CR.SndE2ERatchetParams 'C.X448) -> SubscriptionMode -> AM ()
+confirmQueue (Compatible agentVersion) c cData@ConnData {connId, pqSupport} sq srv connInfo e2eEncryption_ subMode = do
  msg <- mkConfirmation =<< mkAgentConfirmation c cData sq srv connInfo subMode
  sendConfirmation c sq msg
  withStore' c $ \db -> setSndQueueStatus db sq Confirmed
  where
    mkConfirmation :: AgentMessage -> AM MsgBody
    mkConfirmation aMessage = do
-      currentE2EVersion <- asks $ maxVersion . e2eEncryptVRange . config
+      -- the version to be used when PQSupport is disabled
+      currentE2EVersion <- asks $ maxVersion . ($ PQSupportOff) . e2eEncryptVRange . config
      withStore c $ \db -> runExceptT $ do
        void . liftIO $ updateSndIds db connId
        let pqEnc = CR.pqSupportToEnc pqSupport
        (encConnInfo, _) <- agentRatchetEncrypt db cData (smpEncode aMessage) e2eEncConnInfoLength (Just pqEnc) currentE2EVersion
-        pure . smpEncode $ AgentConfirmation {agentVersion = connAgentVersion, e2eEncryption_, encConnInfo}
+        pure . smpEncode $ AgentConfirmation {agentVersion, e2eEncryption_, encConnInfo}

 mkAgentConfirmation :: AgentClient -> ConnData -> SndQueue -> SMPServerWithAuth -> ConnInfo -> SubscriptionMode -> AM AgentMessage
 mkAgentConfirmation c cData sq srv connInfo subMode = do
@@ -2637,7 +2599,8 @@ enqueueConfirmation c cData sq connInfo e2eEncryption_ = do

 storeConfirmation :: AgentClient -> ConnData -> SndQueue -> Maybe (CR.SndE2ERatchetParams 'C.X448) -> AgentMessage -> AM ()
 storeConfirmation c cData@ConnData {connId, pqSupport, connAgentVersion = v} sq e2eEncryption_ agentMsg = do
-  currentE2EVersion <- asks $ maxVersion . e2eEncryptVRange . config
+  -- the version to be used when PQSupport is disabled
+  currentE2EVersion <- asks $ maxVersion . ($ PQSupportOff) . e2eEncryptVRange . config
  withStore c $ \db -> runExceptT $ do
    internalTs <- liftIO getCurrentTime
    (internalId, internalSndId, prevMsgHash) <- liftIO $ updateSndIds db connId
@@ -2657,8 +2620,8 @@ enqueueRatchetKeyMsgs c cData (sq :| sqs) e2eEncryption = do
  mapM_ (lift . enqueueSavedMessage c cData msgId) $ filter isActiveSndQ sqs

 enqueueRatchetKey :: AgentClient -> ConnData -> SndQueue -> CR.RcvE2ERatchetParams 'C.X448 -> AM AgentMsgId
-enqueueRatchetKey c cData@ConnData {connId} sq e2eEncryption = do
-  aVRange <- asks $ smpAgentVRange . config
+enqueueRatchetKey c cData@ConnData {connId, pqSupport} sq e2eEncryption = do
+  aVRange <- asks $ ($ pqSupport) . smpAgentVRange . config
  msgId <- storeRatchetKey $ maxVersion aVRange
  lift $ submitPendingMsg c cData sq
  pure $ unId msgId
@@ -103,9 +103,9 @@ module Simplex.Messaging.Agent.Client
    waitUntilActive,
    UserNetworkInfo (..),
    UserNetworkType (..),
+    UserNetworkState (..),
+    UNSOffline (..),
    waitForUserNetwork,
-    isNetworkOnline,
-    isOnline,
    throwWhenInactive,
    throwWhenNoDelivery,
    beginAgentOperation,
@@ -154,6 +154,7 @@ import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
 import Data.Either (lefts, partitionEithers)
 import Data.Functor (($>))
+import Data.Int (Int64)
 import Data.List (deleteFirstsBy, foldl', partition, (\\))
 import Data.List.NonEmpty (NonEmpty (..), (<|))
 import qualified Data.List.NonEmpty as L
@@ -164,7 +165,7 @@ import Data.Set (Set)
 import qualified Data.Set as S
 import Data.Text (Text)
 import Data.Text.Encoding
-import Data.Time (UTCTime, defaultTimeLocale, formatTime, getCurrentTime)
+import Data.Time (UTCTime, defaultTimeLocale, diffUTCTime, formatTime, getCurrentTime)
 import Data.Time.Clock.System (getSystemTime)
 import Data.Word (Word16)
 import Network.Socket (HostName)
@@ -185,6 +186,7 @@ import qualified Simplex.Messaging.Agent.Store.SQLite.DB as DB
 import Simplex.Messaging.Agent.TRcvQueues (TRcvQueues (getRcvQueues))
 import qualified Simplex.Messaging.Agent.TRcvQueues as RQ
 import Simplex.Messaging.Client
+import Simplex.Messaging.Client.Agent ()
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
@@ -266,8 +268,7 @@ data AgentClient = AgentClient
    xftpServers :: TMap UserId (NonEmpty XFTPServerWithAuth),
    xftpClients :: TMap XFTPTransportSession XFTPClientVar,
    useNetworkConfig :: TVar (NetworkConfig, NetworkConfig), -- (slow, fast) networks
-    userNetworkInfo :: TVar UserNetworkInfo,
-    userNetworkUpdated :: TVar (Maybe UTCTime),
+    userNetworkState :: TVar UserNetworkState,
    subscrConns :: TVar (Set ConnId),
    activeSubs :: TRcvQueues,
    pendingSubs :: TRcvQueues,
@@ -404,20 +405,22 @@ data UserNetworkInfo = UserNetworkInfo
  }
  deriving (Show)

-isNetworkOnline :: AgentClient -> STM Bool
-isNetworkOnline c = isOnline <$> readTVar (userNetworkInfo c)
-
-isOnline :: UserNetworkInfo -> Bool
-isOnline UserNetworkInfo {networkType, online} = networkType /= UNNone && online
-
 data UserNetworkType = UNNone | UNCellular | UNWifi | UNEthernet | UNOther
  deriving (Eq, Show)

+data UserNetworkState = UserNetworkState
+  { networkType :: UserNetworkType,
+    offline :: Maybe UNSOffline
+  }
+  deriving (Show)
+
+data UNSOffline = UNSOffline {offlineDelay :: Int64, offlineFrom :: UTCTime}
+  deriving (Show)
+
 -- | Creates an SMP agent client instance that receives commands and sends responses via 'TBQueue's.
 newAgentClient :: Int -> InitialAgentServers -> Env -> STM AgentClient
 newAgentClient clientId InitialAgentServers {smp, ntf, xftp, netCfg} agentEnv = do
-  let cfg = config agentEnv
-      qSize = tbqSize cfg
+  let qSize = tbqSize $ config agentEnv
  acThread <- newTVar Nothing
  active <- newTVar True
  rcvQ <- newTBQueue qSize
@@ -430,8 +433,7 @@ newAgentClient clientId InitialAgentServers {smp, ntf, xftp, netCfg} agentEnv =
  xftpServers <- newTVar xftp
  xftpClients <- TM.empty
  useNetworkConfig <- newTVar (slowNetworkConfig netCfg, netCfg)
-  userNetworkInfo <- newTVar $ UserNetworkInfo UNOther True
-  userNetworkUpdated <- newTVar Nothing
+  userNetworkState <- newTVar $ UserNetworkState UNOther Nothing
  subscrConns <- newTVar S.empty
  activeSubs <- RQ.empty
  pendingSubs <- RQ.empty
@@ -466,8 +468,7 @@ newAgentClient clientId InitialAgentServers {smp, ntf, xftp, netCfg} agentEnv =
        xftpServers,
        xftpClients,
        useNetworkConfig,
-        userNetworkInfo,
-        userNetworkUpdated,
+        userNetworkState,
        subscrConns,
        activeSubs,
        pendingSubs,
@@ -607,11 +608,12 @@ resubscribeSMPSession c@AgentClient {smpSubWorkers, workerSeq} tSess =
      atomically $ putTMVar (sessionVar v) a
    runSubWorker = do
      ri <- asks $ reconnectInterval . config
+      timeoutCounts <- newTVarIO 0
      withRetryInterval ri $ \_ loop -> do
        pending <- atomically getPending
        forM_ (L.nonEmpty pending) $ \qs -> do
-          liftIO $ waitForUserNetwork c
-          reconnectSMPClient c tSess qs
+          waitForUserNetwork c
+          void . tryAgentError' $ reconnectSMPClient timeoutCounts c tSess qs
          loop
    getPending = RQ.getSessQueues tSess $ pendingSubs c
    cleanup :: SessionVar (Async ()) -> STM ()
@@ -621,23 +623,35 @@ resubscribeSMPSession c@AgentClient {smpSubWorkers, workerSeq} tSess =
      whenM (isEmptyTMVar $ sessionVar v) retry
      removeSessVar v tSess smpSubWorkers

-reconnectSMPClient :: AgentClient -> SMPTransportSession -> NonEmpty RcvQueue -> AM' ()
-reconnectSMPClient c tSess@(_, srv, _) qs = handleNotify $ do
-  cs <- readTVarIO $ RQ.getConnections $ activeSubs c
-  rs <- subscribeQueues c $ L.toList qs
-  let (errs, okConns) = partitionEithers $ map (\(RcvQueue {connId}, r) -> bimap (connId,) (const connId) r) rs
-      conns = filter (`M.notMember` cs) okConns
-  unless (null conns) $ notifySub "" $ UP srv conns
-  let (tempErrs, finalErrs) = partition (temporaryAgentError . snd) errs
-  mapM_ (\(connId, e) -> notifySub connId $ ERR e) finalErrs
-  forM_ (listToMaybe tempErrs) $ \(connId, e) -> do
-    when (null okConns && M.null cs && null finalErrs) . liftIO $
-      closeClient c smpClients tSess
-    notifySub connId $ ERR e
+reconnectSMPClient :: TVar Int -> AgentClient -> SMPTransportSession -> NonEmpty RcvQueue -> AM ()
+reconnectSMPClient tc c tSess@(_, srv, _) qs = do
+  NetworkConfig {tcpTimeout} <- atomically $ getNetworkConfig c
+  -- this allows 3x of timeout per batch of subscription (90 queues per batch empirically)
+  let t = (length qs `div` 90 + 1) * tcpTimeout * 3
+  ExceptT (sequence <$> (t `timeout` runExceptT resubscribe)) >>= \case
+    Just _ -> atomically $ writeTVar tc 0
+    Nothing -> do
+      tc' <- atomically $ stateTVar tc $ \i -> (i + 1, i + 1)
+      maxTC <- asks $ maxSubscriptionTimeouts . config
+      let err = if tc' >= maxTC then CRITICAL True else INTERNAL
+          msg = show tc' <> " consecutive subscription timeouts: " <> show (length qs) <> " queues, transport session: " <> show tSess
+      atomically $ writeTBQueue (subQ c) ("", "", APC SAEConn $ ERR $ err msg)
  where
-    handleNotify :: AM' () -> AM' ()
-    handleNotify = E.handleAny $ notifySub "" . ERR . INTERNAL . show
-    notifySub :: forall e. AEntityI e => ConnId -> ACommand 'Agent e -> AM' ()
+    resubscribe :: AM ()
+    resubscribe = do
+      cs <- readTVarIO $ RQ.getConnections $ activeSubs c
+      rs <- lift . subscribeQueues c $ L.toList qs
+      let (errs, okConns) = partitionEithers $ map (\(RcvQueue {connId}, r) -> bimap (connId,) (const connId) r) rs
+      liftIO $ do
+        let conns = filter (`M.notMember` cs) okConns
+        unless (null conns) $ notifySub "" $ UP srv conns
+      let (tempErrs, finalErrs) = partition (temporaryAgentError . snd) errs
+      liftIO $ mapM_ (\(connId, e) -> notifySub connId $ ERR e) finalErrs
+      forM_ (listToMaybe tempErrs) $ \(_, err) -> do
+        when (null okConns && M.null cs && null finalErrs) . liftIO $
+          closeClient c smpClients tSess
+        throwError err
+    notifySub :: forall e. AEntityI e => ConnId -> ACommand 'Agent e -> IO ()
    notifySub connId cmd = atomically $ writeTBQueue (subQ c) ("", connId, APC (sAEntity @e) cmd)

 getNtfServerClient :: AgentClient -> NtfTransportSession -> AM NtfClient
@@ -732,17 +746,43 @@ getClientConfig c cfgSel = do
 getNetworkConfig :: AgentClient -> STM NetworkConfig
 getNetworkConfig c = do
  (slowCfg, fastCfg) <- readTVar (useNetworkConfig c)
-  UserNetworkInfo {networkType} <- readTVar $ userNetworkInfo c
+  UserNetworkState {networkType} <- readTVar (userNetworkState c)
  pure $ case networkType of
    UNCellular -> slowCfg
    UNNone -> slowCfg
    _ -> fastCfg

-waitForUserNetwork :: AgentClient -> IO ()
-waitForUserNetwork c =
-  unlessM (atomically $ isNetworkOnline c) $ do
-    delay <- registerDelay $ userNetworkInterval $ config $ agentEnv c
-    atomically $ unlessM (isNetworkOnline c) $ unlessM (readTVar delay) retry
+waitForUserNetwork :: AgentClient -> AM' ()
+waitForUserNetwork AgentClient {userNetworkState} =
+  readTVarIO userNetworkState >>= mapM_ waitWhileOffline . offline
+  where
+    waitWhileOffline UNSOffline {offlineDelay = d} =
+      unlessM (liftIO $ waitOnline d False) $ do
+        -- network delay reached, increase delay
+        ts' <- liftIO getCurrentTime
+        ni <- asks $ userNetworkInterval . config
+        atomically $ do
+          ns@UserNetworkState {offline} <- readTVar userNetworkState
+          forM_ offline $ \UNSOffline {offlineDelay = d', offlineFrom = ts} ->
+            -- Using `min` to avoid multiple updates in a short period of time
+            -- and to reset `offlineDelay` if network went `on` and `off` again.
+            writeTVar userNetworkState $!
+              let d'' = nextRetryDelay (diffToMicroseconds $ diffUTCTime ts' ts) (min d d') ni
+               in ns {offline = Just UNSOffline {offlineDelay = d'', offlineFrom = ts}}
+    waitOnline :: Int64 -> Bool -> IO Bool
+    waitOnline t online'
+      | t <= 0 = pure online'
+      | otherwise =
+          registerDelay (fromIntegral maxWait)
+            >>= atomically . onlineOrDelay
+            >>= waitOnline (t - maxWait)
+      where
+        maxWait = min t $ fromIntegral (maxBound :: Int)
+        onlineOrDelay delay = do
+          online <- isNothing . offline <$> readTVar userNetworkState
+          expired <- readTVar delay
+          unless (online || expired) retry
+          pure online

 closeAgentClient :: AgentClient -> IO ()
 closeAgentClient c = do
@@ -826,15 +866,15 @@ withInvLock' :: AgentClient -> ByteString -> String -> AM' a -> AM' a
 withInvLock' AgentClient {invLocks} = withLockMap invLocks
 {-# INLINE withInvLock' #-}

-withConnLocks :: AgentClient -> Set ConnId -> String -> AM' a -> AM' a
-withConnLocks AgentClient {connLocks} = withLocksMap_ connLocks
+withConnLocks :: AgentClient -> [ConnId] -> String -> AM' a -> AM' a
+withConnLocks AgentClient {connLocks} = withLocksMap_ connLocks . filter (not . B.null)
 {-# INLINE withConnLocks #-}

 withLockMap :: (Ord k, MonadUnliftIO m) => TMap k Lock -> k -> String -> m a -> m a
 withLockMap = withGetLock . getMapLock
 {-# INLINE withLockMap #-}

-withLocksMap_ :: (Ord k, MonadUnliftIO m) => TMap k Lock -> Set k -> String -> m a -> m a
+withLocksMap_ :: (Ord k, MonadUnliftIO m) => TMap k Lock -> [k] -> String -> m a -> m a
 withLocksMap_ = withGetLocks . getMapLock
 {-# INLINE withLocksMap_ #-}

@@ -1102,6 +1142,8 @@ temporaryAgentError :: AgentErrorType -> Bool
 temporaryAgentError = \case
  BROKER _ NETWORK -> True
  BROKER _ TIMEOUT -> True
+  SMP (SMP.PROXY SMP.TIMEOUT) -> True
+  NTF (SMP.PROXY SMP.TIMEOUT) -> True
  INACTIVE -> True
  _ -> False
 {-# INLINE temporaryAgentError #-}
@@ -54,8 +54,9 @@ import Simplex.Messaging.Agent.RetryInterval
 import Simplex.Messaging.Agent.Store.SQLite
 import qualified Simplex.Messaging.Agent.Store.SQLite.Migrations as Migrations
 import Simplex.Messaging.Client
+import Simplex.Messaging.Client.Agent ()
 import qualified Simplex.Messaging.Crypto as C
-import Simplex.Messaging.Crypto.Ratchet (VersionRangeE2E, supportedE2EEncryptVRange)
+import Simplex.Messaging.Crypto.Ratchet (PQSupport, VersionRangeE2E, supportedE2EEncryptVRange)
 import Simplex.Messaging.Notifications.Client (defaultNTFClientConfig)
 import Simplex.Messaging.Notifications.Transport (NTFVersion)
 import Simplex.Messaging.Notifications.Types
@@ -91,8 +92,7 @@ data AgentConfig = AgentConfig
    xftpCfg :: XFTPClientConfig,
    reconnectInterval :: RetryInterval,
    messageRetryInterval :: RetryInterval2,
-    userNetworkInterval :: Int,
-    userOfflineDelay :: NominalDiffTime,
+    userNetworkInterval :: RetryInterval,
    messageTimeout :: NominalDiffTime,
    connDeleteDeliveryTimeout :: NominalDiffTime,
    helloTimeout :: NominalDiffTime,
@@ -101,6 +101,7 @@ data AgentConfig = AgentConfig
    cleanupInterval :: Int64,
    cleanupStepInterval :: Int,
    maxWorkerRestartsPerMin :: Int,
+    maxSubscriptionTimeouts :: Int,
    storedMsgDataTTL :: NominalDiffTime,
    rcvFilesTTL :: NominalDiffTime,
    sndFilesTTL :: NominalDiffTime,
@@ -116,8 +117,8 @@ data AgentConfig = AgentConfig
    caCertificateFile :: FilePath,
    privateKeyFile :: FilePath,
    certificateFile :: FilePath,
-    e2eEncryptVRange :: VersionRangeE2E,
-    smpAgentVRange :: VersionRangeSMPA,
+    e2eEncryptVRange :: PQSupport -> VersionRangeE2E,
+    smpAgentVRange :: PQSupport -> VersionRangeSMPA,
    smpClientVRange :: VersionRangeSMPC
  }

@@ -146,6 +147,14 @@ defaultMessageRetryInterval =
          }
    }

+defaultUserNetworkInterval :: RetryInterval
+defaultUserNetworkInterval =
+  RetryInterval
+    { initialInterval = 1200_000000, -- 20 minutes
+      increaseAfter = 0,
+      maxInterval = 7200_000000 -- 2 hours
+    }
+
 defaultAgentConfig :: AgentConfig
 defaultAgentConfig =
  AgentConfig
@@ -161,8 +170,7 @@ defaultAgentConfig =
      xftpCfg = defaultXFTPClientConfig,
      reconnectInterval = defaultReconnectInterval,
      messageRetryInterval = defaultMessageRetryInterval,
-      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
+      userNetworkInterval = defaultUserNetworkInterval,
      messageTimeout = 2 * nominalDay,
      connDeleteDeliveryTimeout = 2 * nominalDay,
      helloTimeout = 2 * nominalDay,
@@ -171,6 +179,9 @@ defaultAgentConfig =
      cleanupInterval = 30 * 60 * 1000000, -- 30 minutes
      cleanupStepInterval = 200000, -- 200ms
      maxWorkerRestartsPerMin = 5,
+      -- 3 consecutive subscription timeouts will result in alert to the user
+      -- this is a fallback, as the timeout set to 3x of expected timeout, to avoid potential locking.
+      maxSubscriptionTimeouts = 3,
      storedMsgDataTTL = 21 * nominalDay,
      rcvFilesTTL = 2 * nominalDay,
      sndFilesTTL = nominalDay,
@@ -12,8 +12,6 @@ import Control.Monad (void)
 import Control.Monad.Except (ExceptT (..), runExceptT)
 import Control.Monad.IO.Unlift
 import Data.Functor (($>))
-import Data.Set (Set)
-import qualified Data.Set as S
 import UnliftIO.Async (forConcurrently)
 import qualified UnliftIO.Exception as E
 import UnliftIO.STM
@@ -41,11 +39,13 @@ withGetLock getLock key name a =
    (atomically . takeTMVar)
    (const a)

-withGetLocks :: MonadUnliftIO m => (k -> STM Lock) -> Set k -> String -> m a -> m a
+withGetLocks :: MonadUnliftIO m => (k -> STM Lock) -> [k] -> String -> m a -> m a
 withGetLocks getLock keys name = E.bracket holdLocks releaseLocks . const
  where
-    holdLocks = forConcurrently (S.toList keys) $ \key -> atomically $ getPutLock getLock key name
-    releaseLocks = mapM_ (atomically . takeTMVar)
+    holdLocks = forConcurrently keys $ \key -> atomically $ getPutLock getLock key name
+    -- only this withGetLocks would be holding the locks,
+    -- so it's safe to combine all lock releases into one transaction
+    releaseLocks = atomically . mapM_ takeTMVar

 -- getLock and putTMVar can be in one transaction on the assumption that getLock doesn't write in case the lock already exists,
 -- and in case it is created and added to some shared resource (we use TMap) it also helps avoid contention for the newly created lock.
@@ -33,6 +33,7 @@ import Simplex.Messaging.Agent.Protocol (ACommand (..), APartyCmd (..), AgentErr
 import Simplex.Messaging.Agent.RetryInterval
 import Simplex.Messaging.Agent.Store
 import Simplex.Messaging.Agent.Store.SQLite
+import Simplex.Messaging.Client.Agent ()
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Notifications.Protocol (NtfSubStatus (..), NtfTknStatus (..), SMPQueueNtf (..))
 import Simplex.Messaging.Notifications.Types
@@ -160,7 +161,7 @@ runNtfWorker c srv Worker {doWork} = do
          logInfo $ "runNtfWorker, nextSub " <> tshow nextSub
          ri <- asks $ reconnectInterval . config
          withRetryInterval ri $ \_ loop -> do
-            liftIO $ waitForUserNetwork c
+            lift $ waitForUserNetwork c
            processSub nextSub
              `catchAgentError` retryOnError c "NtfWorker" loop (workerInternalError c connId . show)
    processSub :: (NtfSubscription, NtfSubNTFAction, NtfActionTs) -> AM ()
@@ -244,7 +245,7 @@ runNtfSMPWorker c srv Worker {doWork} = do
          logInfo $ "runNtfSMPWorker, nextSub " <> tshow nextSub
          ri <- asks $ reconnectInterval . config
          withRetryInterval ri $ \_ loop -> do
-            liftIO $ waitForUserNetwork c
+            lift $ waitForUserNetwork c
            processSub nextSub
              `catchAgentError` retryOnError c "NtfSMPWorker" loop (workerInternalError c connId . show)
    processSub :: (NtfSubscription, NtfSubSMPAction, NtfActionTs) -> AM ()
@@ -44,7 +44,7 @@ module Simplex.Messaging.Agent.Protocol
    currentSMPAgentVersion,
    supportedSMPAgentVRange,
    e2eEncConnInfoLength,
-    e2eEncAgentMsgLength,
+    e2eEncUserMsgLength,

    -- * SMP agent protocol types
    ConnInfo,
@@ -272,11 +272,16 @@ deliveryRcptsSMPAgentVersion = VersionSMPA 4
 pqdrSMPAgentVersion :: VersionSMPA
 pqdrSMPAgentVersion = VersionSMPA 5

+-- TODO v5.7 increase to 5
 currentSMPAgentVersion :: VersionSMPA
-currentSMPAgentVersion = VersionSMPA 5
+currentSMPAgentVersion = VersionSMPA 4

-supportedSMPAgentVRange :: VersionRangeSMPA
-supportedSMPAgentVRange = mkVersionRange duplexHandshakeSMPAgentVersion currentSMPAgentVersion
+-- TODO v5.7 remove dependency of version range on whether PQ support is needed
+supportedSMPAgentVRange :: PQSupport -> VersionRangeSMPA
+supportedSMPAgentVRange pq =
+  mkVersionRange duplexHandshakeSMPAgentVersion $ case pq of
+    PQSupportOn -> pqdrSMPAgentVersion
+    PQSupportOff -> currentSMPAgentVersion

 -- it is shorter to allow all handshake headers,
 -- including E2E (double-ratchet) parameters and
@@ -287,8 +292,8 @@ e2eEncConnInfoLength v = \case
  PQSupportOn | v >= pqdrSMPAgentVersion -> 11122
  _ -> 14848

-e2eEncAgentMsgLength :: VersionSMPA -> PQSupport -> Int
-e2eEncAgentMsgLength v = \case
+e2eEncUserMsgLength :: VersionSMPA -> PQSupport -> Int
+e2eEncUserMsgLength v = \case
  -- reduced by 2222 (the increase of message ratchet header size)
  PQSupportOn | v >= pqdrSMPAgentVersion -> 13634
  _ -> 15856
@@ -49,7 +49,7 @@ runSMPAgentBlocking (ATransport t) cfg@AgentConfig {tcpPort, caCertificateFile,
    smpAgent :: forall c. Transport c => TProxy c -> ServiceName -> Env -> IO ()
    smpAgent _ port env = do
      -- tlsServerParams is not in Env to avoid breaking functional API w/t key and certificate generation
-      tlsServerParams <- loadTLSServerParams caCertificateFile certificateFile privateKeyFile Nothing
+      tlsServerParams <- loadTLSServerParams caCertificateFile certificateFile privateKeyFile
      clientId <- newTVarIO initClientId
      runTransportServer started port tlsServerParams defaultTransportServerConfig $ \(h :: c) -> do
        putLn h $ "Welcome to SMP agent v" <> B.pack simplexMQVersion
@@ -54,6 +54,9 @@ module Simplex.Messaging.Client
    suspendSMPQueue,
    deleteSMPQueue,
    deleteSMPQueues,
+    createSMPProxySession,
+    proxySMPMessage,
+    forwardSMPMessage,
    sendProtocolCommand,

    -- * Supporting types and client configuration
@@ -69,6 +72,7 @@ module Simplex.Messaging.Client
    chooseTransportHost,
    proxyUsername,
    temporaryClientError,
+    smpProxyError,
    ServerTransmission,
    ClientCommand,

@@ -97,20 +101,23 @@ import Data.List (find)
 import Data.List.NonEmpty (NonEmpty (..))
 import qualified Data.List.NonEmpty as L
 import Data.Maybe (fromMaybe)
-import Data.Time.Clock (UTCTime (..), diffUTCTime, getCurrentTime)
+import Data.Time.Clock (UTCTime (..), getCurrentTime)
+import qualified Data.X509 as X
+import qualified Data.X509.Validation as XV
 import Network.Socket (ServiceName)
 import Numeric.Natural
 import qualified Simplex.Messaging.Crypto as C
+import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Parsers (defaultJSON, dropPrefix, enumJSON)
 import Simplex.Messaging.Protocol
 import Simplex.Messaging.TMap (TMap)
 import qualified Simplex.Messaging.TMap as TM
 import Simplex.Messaging.Transport
-import Simplex.Messaging.Transport.Client (SocksProxy, TransportClientConfig (..), TransportHost (..), defaultTcpConnectTimeout, runTransportClient)
+import Simplex.Messaging.Transport.Client (SocksProxy, TransportClientConfig (..), TransportHost (..), runTransportClient)
 import Simplex.Messaging.Transport.KeepAlive
 import Simplex.Messaging.Transport.WebSockets (WS)
-import Simplex.Messaging.Util (bshow, diffToMicroseconds, raceAny_, threadDelay', whenM)
+import Simplex.Messaging.Util (bshow, liftEitherWith, raceAny_, threadDelay')
 import Simplex.Messaging.Version
 import System.Timeout (timeout)

@@ -129,26 +136,20 @@ data PClient v err msg = PClient
    transportSession :: TransportSession msg,
    transportHost :: TransportHost,
    tcpTimeout :: Int,
-    rcvConcurrency :: Int,
-    sendPings :: TVar Bool,
-    lastReceived :: TVar UTCTime,
-    timeoutErrorCount :: TVar Int,
+    pingErrorCount :: TVar Int,
    clientCorrId :: TVar ChaChaDRG,
    sentCommands :: TMap CorrId (Request err msg),
-    sndQ :: TBQueue (TVar Bool, ByteString),
+    sndQ :: TBQueue ByteString,
    rcvQ :: TBQueue (NonEmpty (SignedTransmission err msg)),
    msgQ :: Maybe (TBQueue (ServerTransmission v msg))
  }

 smpClientStub :: TVar ChaChaDRG -> ByteString -> VersionSMP -> Maybe (THandleAuth 'TClient) -> STM SMPClient
 smpClientStub g sessionId thVersion thAuth = do
-  let ts = UTCTime (read "2024-03-31") 0
  connected <- newTVar False
  clientCorrId <- C.newRandomDRG g
  sentCommands <- TM.empty
-  sendPings <- newTVar False
-  lastReceived <- newTVar ts
-  timeoutErrorCount <- newTVar 0
+  pingErrorCount <- newTVar 0
  sndQ <- newTBQueue 100
  rcvQ <- newTBQueue 100
  return
@@ -163,17 +164,14 @@ smpClientStub g sessionId thVersion thAuth = do
              implySessId = thVersion >= authCmdsSMPVersion,
              batch = True
            },
-        sessionTs = ts,
+        sessionTs = UTCTime (read "2024-03-31") 0,
        client_ =
          PClient
            { connected,
              transportSession = (1, "smp://LcJUMfVhwD8yxjAiSaDzzGF3-kLG4Uh0Fl_ZIjrRwjI=@localhost:5001", Nothing),
              transportHost = "localhost",
              tcpTimeout = 15_000_000,
-              rcvConcurrency = 8,
-              sendPings,
-              lastReceived,
-              timeoutErrorCount,
+              pingErrorCount,
              clientCorrId,
              sentCommands,
              sndQ,
@@ -188,7 +186,7 @@ type SMPClient = ProtocolClient SMPVersion ErrorType BrokerMsg
 type ClientCommand msg = (Maybe C.APrivateAuthKey, EntityId, ProtoCommand msg)

 -- | Type synonym for transmission from some SPM server queue.
-type ServerTransmission v msg = (TransportSession msg, Version v, SessionId, Bool, EntityId, msg)
+type ServerTransmission v msg = (TransportSession msg, Version v, SessionId, EntityId, msg)

 data HostMode
  = -- | prefer (or require) onion hosts when connecting via SOCKS proxy
@@ -215,13 +213,11 @@ data NetworkConfig = NetworkConfig
    tcpTimeout :: Int,
    -- | additional timeout per kilobyte (1024 bytes) to be sent
    tcpTimeoutPerKb :: Int64,
-    -- | break response timeouts into groups, so later responses get later deadlines
-    rcvConcurrency :: Int,
    -- | TCP keep-alive options, Nothing to skip enabling keep-alive
    tcpKeepAlive :: Maybe KeepAliveOpts,
    -- | period for SMP ping commands (microseconds, 0 to disable)
    smpPingInterval :: Int64,
-    -- | the count of timeout errors after which SMP client terminates (and will be reconnected), 0 to disable
+    -- | the count of PING errors after which SMP client terminates (and will be reconnected), 0 to disable
    smpPingCount :: Int,
    logTLSErrors :: Bool
  }
@@ -237,10 +233,9 @@ defaultNetworkConfig =
      hostMode = HMOnionViaSocks,
      requiredHostMode = False,
      sessionMode = TSMUser,
-      tcpConnectTimeout = defaultTcpConnectTimeout,
+      tcpConnectTimeout = 20_000_000,
      tcpTimeout = 15_000_000,
      tcpTimeoutPerKb = 5_000,
-      rcvConcurrency = 8,
      tcpKeepAlive = Just defaultKeepAliveOpts,
      smpPingInterval = 600_000_000, -- 10min
      smpPingCount = 3,
@@ -248,8 +243,8 @@ defaultNetworkConfig =
    }

 transportClientConfig :: NetworkConfig -> TransportClientConfig
-transportClientConfig NetworkConfig {socksProxy, tcpConnectTimeout, tcpKeepAlive, logTLSErrors} =
-  TransportClientConfig {socksProxy, tcpConnectTimeout, tcpKeepAlive, logTLSErrors, clientCredentials = Nothing, alpn = Nothing}
+transportClientConfig NetworkConfig {socksProxy, tcpKeepAlive, logTLSErrors} =
+  TransportClientConfig {socksProxy, tcpKeepAlive, logTLSErrors, clientCredentials = Nothing, alpn = Nothing}
 {-# INLINE transportClientConfig #-}

 -- | protocol client configuration.
@@ -260,7 +255,6 @@ data ProtocolClientConfig v = ProtocolClientConfig
    defaultTransport :: (ServiceName, ATransport),
    -- | network configuration
    networkConfig :: NetworkConfig,
-    clientALPN :: Maybe [ALPN],
    -- | client-server protocol version range
    serverVRange :: VersionRange v,
    -- | agree shared session secret (used in SMP proxy)
@@ -268,25 +262,23 @@ data ProtocolClientConfig v = ProtocolClientConfig
  }

 -- | Default protocol client configuration.
-defaultClientConfig :: Maybe [ALPN] -> VersionRange v -> ProtocolClientConfig v
-defaultClientConfig clientALPN serverVRange =
+defaultClientConfig :: VersionRange v -> ProtocolClientConfig v
+defaultClientConfig serverVRange =
  ProtocolClientConfig
    { qSize = 64,
      defaultTransport = ("443", transport @TLS),
      networkConfig = defaultNetworkConfig,
-      clientALPN,
      serverVRange,
      agreeSecret = False
    }
 {-# INLINE defaultClientConfig #-}

 defaultSMPClientConfig :: ProtocolClientConfig SMPVersion
-defaultSMPClientConfig = defaultClientConfig (Just supportedSMPHandshakes) supportedClientSMPRelayVRange
+defaultSMPClientConfig = defaultClientConfig supportedClientSMPRelayVRange
 {-# INLINE defaultSMPClientConfig #-}

 data Request err msg = Request
-  { corrId :: CorrId,
-    entityId :: EntityId,
+  { entityId :: EntityId,
    responseVar :: TMVar (Either (ProtocolClientError err) msg)
  }

@@ -334,20 +326,18 @@ type TransportSession msg = (UserId, ProtoServer msg, Maybe EntityId)
 -- A single queue can be used for multiple 'SMPClient' instances,
 -- as 'SMPServerTransmission' includes server information.
 getProtocolClient :: forall v err msg. Protocol v err msg => TVar ChaChaDRG -> TransportSession msg -> ProtocolClientConfig v -> Maybe (TBQueue (ServerTransmission v msg)) -> (ProtocolClient v err msg -> IO ()) -> IO (Either (ProtocolClientError err) (ProtocolClient v err msg))
-getProtocolClient g transportSession@(_, srv, _) cfg@ProtocolClientConfig {qSize, networkConfig, clientALPN, serverVRange, agreeSecret} msgQ disconnected = do
+getProtocolClient g transportSession@(_, srv, _) cfg@ProtocolClientConfig {qSize, networkConfig, serverVRange, agreeSecret} msgQ disconnected = do
  case chooseTransportHost networkConfig (host srv) of
    Right useHost ->
-      (getCurrentTime >>= atomically . mkProtocolClient useHost >>= runClient useTransport useHost)
+      (atomically (mkProtocolClient useHost) >>= runClient useTransport useHost)
        `catch` \(e :: IOException) -> pure . Left $ PCEIOError e
    Left e -> pure $ Left e
  where
-    NetworkConfig {tcpConnectTimeout, tcpTimeout, rcvConcurrency, smpPingInterval} = networkConfig
-    mkProtocolClient :: TransportHost -> UTCTime -> STM (PClient v err msg)
-    mkProtocolClient transportHost ts = do
+    NetworkConfig {tcpConnectTimeout, tcpTimeout, smpPingInterval} = networkConfig
+    mkProtocolClient :: TransportHost -> STM (PClient v err msg)
+    mkProtocolClient transportHost = do
      connected <- newTVar False
-      sendPings <- newTVar False
-      lastReceived <- newTVar ts
-      timeoutErrorCount <- newTVar 0
+      pingErrorCount <- newTVar 0
      clientCorrId <- C.newRandomDRG g
      sentCommands <- TM.empty
      sndQ <- newTBQueue qSize
@@ -358,12 +348,9 @@ getProtocolClient g transportSession@(_, srv, _) cfg@ProtocolClientConfig {qSize
            transportSession,
            transportHost,
            tcpTimeout,
-            sendPings,
-            lastReceived,
-            timeoutErrorCount,
+            pingErrorCount,
            clientCorrId,
            sentCommands,
-            rcvConcurrency,
            sndQ,
            rcvQ,
            msgQ
@@ -372,7 +359,7 @@ getProtocolClient g transportSession@(_, srv, _) cfg@ProtocolClientConfig {qSize
    runClient :: (ServiceName, ATransport) -> TransportHost -> PClient v err msg -> IO (Either (ProtocolClientError err) (ProtocolClient v err msg))
    runClient (port', ATransport t) useHost c = do
      cVar <- newEmptyTMVarIO
-      let tcConfig = (transportClientConfig networkConfig) {alpn = clientALPN}
+      let tcConfig = transportClientConfig networkConfig
          username = proxyUsername transportSession
      action <-
        async $
@@ -398,7 +385,6 @@ getProtocolClient g transportSession@(_, srv, _) cfg@ProtocolClientConfig {qSize
        Right th@THandle {params} -> do
          sessionTs <- getCurrentTime
          let c' = ProtocolClient {action = Nothing, client_ = c, thParams = params, sessionTs}
-          atomically $ writeTVar (lastReceived c) sessionTs
          atomically $ do
            writeTVar (connected c) True
            putTMVar cVar $ Right c'
@@ -406,48 +392,36 @@ getProtocolClient g transportSession@(_, srv, _) cfg@ProtocolClientConfig {qSize
            `finally` disconnected c'

    send :: Transport c => ProtocolClient v err msg -> THandle v c 'TClient -> IO ()
-    send ProtocolClient {client_ = PClient {sndQ}} h = forever $ atomically (readTBQueue sndQ) >>= \(active, s) -> whenM (readTVarIO active) (void $ tPutLog h s)
+    send ProtocolClient {client_ = PClient {sndQ}} h = forever $ atomically (readTBQueue sndQ) >>= tPutLog h

    receive :: Transport c => ProtocolClient v err msg -> THandle v c 'TClient -> IO ()
-    receive ProtocolClient {client_ = PClient {rcvQ, lastReceived, timeoutErrorCount}} h = forever $ do
-      tGet h >>= atomically . writeTBQueue rcvQ
-      getCurrentTime >>= atomically . writeTVar lastReceived
-      atomically $ writeTVar timeoutErrorCount 0
+    receive ProtocolClient {client_ = PClient {rcvQ}} h = forever $ tGet h >>= atomically . writeTBQueue rcvQ

    ping :: ProtocolClient v err msg -> IO ()
-    ping c@ProtocolClient {client_ = PClient {sendPings, lastReceived, timeoutErrorCount}} = loop smpPingInterval
+    ping c@ProtocolClient {client_ = PClient {pingErrorCount}} = do
+      threadDelay' smpPingInterval
+      runExceptT (sendProtocolCommand c Nothing "" $ protocolPing @v @err @msg) >>= \case
+        Left PCEResponseTimeout -> do
+          cnt <- atomically $ stateTVar pingErrorCount $ \cnt -> (cnt + 1, cnt + 1)
+          when (maxCnt == 0 || cnt < maxCnt) $ ping c
+        _ -> ping c -- sendProtocolCommand resets pingErrorCount
      where
-        loop :: Int64 -> IO ()
-        loop delay = do
-          threadDelay' delay
-          diff <- diffUTCTime <$> getCurrentTime <*> readTVarIO lastReceived
-          let idle = diffToMicroseconds diff
-              remaining = smpPingInterval - idle
-          if remaining > 1_000_000 -- delay pings only for significant time
-            then loop remaining
-            else do
-              whenM (readTVarIO sendPings) $ void . runExceptT $ sendProtocolCommand c Nothing "" (protocolPing @v @err @msg)
-              -- sendProtocolCommand/getResponse updates counter for each command
-              cnt <- readTVarIO timeoutErrorCount
-              -- drop client when maxCnt of commands have timed out in sequence, but only after some time has passed after last received response
-              when (maxCnt == 0 || cnt < maxCnt || diff < recoverWindow) $ loop smpPingInterval
-        recoverWindow = 15 * 60 -- seconds
        maxCnt = smpPingCount networkConfig

    process :: ProtocolClient v err msg -> IO ()
    process c = forever $ atomically (readTBQueue $ rcvQ $ client_ c) >>= mapM_ (processMsg c)

    processMsg :: ProtocolClient v err msg -> SignedTransmission err msg -> IO ()
-    processMsg c@ProtocolClient {client_ = PClient {sentCommands}} (_, _, (corrId, entId, respOrErr))
-      | isResponse =
+    processMsg c@ProtocolClient {client_ = PClient {sentCommands}} (_, _, (corrId, entId, respOrErr)) =
+      if B.null $ bs corrId
+        then sendMsg respOrErr
+        else do
          atomically (TM.lookup corrId sentCommands) >>= \case
            Nothing -> sendMsg respOrErr
            Just Request {entityId, responseVar} -> atomically $ do
              TM.delete corrId sentCommands
              putTMVar responseVar $ response entityId
-      | otherwise = sendMsg respOrErr
      where
-        isResponse = not $ B.null $ bs corrId
        response entityId
          | entityId == entId =
              case respOrErr of
@@ -458,7 +432,7 @@ getProtocolClient g transportSession@(_, srv, _) cfg@ProtocolClientConfig {qSize
          | otherwise = Left . PCEUnexpectedResponse $ bshow respOrErr
        sendMsg :: Either err msg -> IO ()
        sendMsg = \case
-          Right msg -> atomically $ mapM_ (`writeTBQueue` serverTransmission c isResponse entId msg) msgQ
+          Right msg -> atomically $ mapM_ (`writeTBQueue` serverTransmission c entId msg) msgQ
          Left e -> putStrLn $ "SMP client error: " <> show e

 proxyUsername :: TransportSession msg -> ByteString
@@ -510,6 +484,18 @@ temporaryClientError = \case
  _ -> False
 {-# INLINE temporaryClientError #-}

+smpProxyError :: SMPClientError -> ErrorType
+smpProxyError = \case
+  PCEProtocolError et -> PROXY (PROTOCOL et)
+  PCEResponseError et -> PROXY (RESPONSE et)
+  PCEUnexpectedResponse bs -> PROXY (UNEXPECTED $ B.unpack $ B.take 32 bs)
+  PCEResponseTimeout -> PROXY TIMEOUT
+  PCENetworkError -> PROXY NETWORK
+  PCEIncompatibleHost -> PROXY BAD_HOST
+  PCETransportError t -> PROXY (TRANSPORT t)
+  PCECryptoError _ -> INTERNAL
+  PCEIOError _ -> INTERNAL
+
 -- | Create a new SMP queue.
 --
 -- https://github.com/simplex-chat/simplexmq/blob/master/protocol/simplex-messaging.md#create-queue-command
@@ -529,18 +515,15 @@ createSMPQueue c (rKey, rpKey) dhKey auth subMode =
 --
 -- https://github.com/simplex-chat/simplexmq/blob/master/protocol/simplex-messaging.md#subscribe-to-queue
 subscribeSMPQueue :: SMPClient -> RcvPrivateAuthKey -> RecipientId -> ExceptT SMPClientError IO ()
-subscribeSMPQueue c@ProtocolClient {client_ = PClient {sendPings}} rpKey rId = do
-  liftIO . atomically $ writeTVar sendPings True
+subscribeSMPQueue c rpKey rId =
  sendSMPCommand c (Just rpKey) rId SUB >>= \case
-    OK -> pure ()
+    OK -> return ()
    cmd@MSG {} -> liftIO $ writeSMPMessage c rId cmd
    r -> throwE . PCEUnexpectedResponse $ bshow r

 -- | Subscribe to multiple SMP queues batching commands if supported.
 subscribeSMPQueues :: SMPClient -> NonEmpty (RcvPrivateAuthKey, RecipientId) -> IO (NonEmpty (Either SMPClientError ()))
-subscribeSMPQueues c@ProtocolClient {client_ = PClient {sendPings}} qs = do
-  atomically $ writeTVar sendPings True
-  sendProtocolCommands c cs >>= mapM (processSUBResponse c)
+subscribeSMPQueues c qs = sendProtocolCommands c cs >>= mapM (processSUBResponse c)
  where
    cs = L.map (\(rpKey, rId) -> (Just rpKey, rId, Cmd SRecipient SUB)) qs

@@ -558,11 +541,11 @@ processSUBResponse c (Response rId r) = case r of
  Left e -> pure $ Left e

 writeSMPMessage :: SMPClient -> RecipientId -> BrokerMsg -> IO ()
-writeSMPMessage c rId msg = atomically $ mapM_ (`writeTBQueue` serverTransmission c False rId msg) (msgQ $ client_ c)
+writeSMPMessage c rId msg = atomically $ mapM_ (`writeTBQueue` serverTransmission c rId msg) (msgQ $ client_ c)

-serverTransmission :: ProtocolClient v err msg -> Bool -> RecipientId -> msg -> ServerTransmission v msg
-serverTransmission ProtocolClient {thParams = THandleParams {thVersion, sessionId}, client_ = PClient {transportSession}} isResponse entityId message =
-  (transportSession, thVersion, sessionId, isResponse, entityId, message)
+serverTransmission :: ProtocolClient v err msg -> RecipientId -> msg -> ServerTransmission v msg
+serverTransmission ProtocolClient {thParams = THandleParams {thVersion, sessionId}, client_ = PClient {transportSession}} entityId message =
+  (transportSession, thVersion, sessionId, entityId, message)

 -- | Get message from SMP queue. The server returns ERR PROHIBITED if a client uses SUB and GET via the same transport connection for the same queue
 --
@@ -663,6 +646,102 @@ deleteSMPQueues :: SMPClient -> NonEmpty (RcvPrivateAuthKey, RecipientId) -> IO
 deleteSMPQueues = okSMPCommands DEL
 {-# INLINE deleteSMPQueues #-}

+-- TODO picture
+
+-- send PRXY :: SMPServer -> Maybe BasicAuth -> Command Sender
+-- receives PKEY :: SessionId -> X.CertificateChain -> X.SignedExact X.PubKey -> BrokerMsg
+createSMPProxySession :: SMPClient -> SMPServer -> Maybe BasicAuth -> ExceptT SMPClientError IO (SessionId, VersionSMP, C.PublicKeyX25519)
+createSMPProxySession c relayServ@ProtocolServer {keyHash = C.KeyHash kh} proxyAuth =
+  sendSMPCommand c Nothing "" (PRXY relayServ proxyAuth) >>= \case
+    -- XXX: rfc says sessionId should be in the entityId of response
+    PKEY sId vr (chain, key) -> do
+      case supportedClientSMPRelayVRange `compatibleVersion` vr of
+        Nothing -> throwE PCEIncompatibleHost -- TODO different error
+        Just (Compatible v) -> liftEitherWith x509Error $ (sId,v,) <$> validateRelay chain key
+    r -> throwE . PCEUnexpectedResponse $ bshow r
+  where
+    x509Error :: String -> SMPClientError
+    x509Error _msg = PCEResponseError $ error "TODO: x509 error" -- TODO different error
+    validateRelay :: X.CertificateChain -> X.SignedExact X.PubKey -> Either String C.PublicKeyX25519
+    validateRelay (X.CertificateChain cert) exact = do
+      serverKey <- case cert of
+        [leaf, ca]
+          | XV.Fingerprint kh == XV.getFingerprint ca X.HashSHA256 ->
+              C.x509ToPublic (X.certPubKey . X.signedObject $ X.getSigned leaf, []) >>= C.pubKey
+        _ -> throwError "bad certificate"
+      pubKey <- C.verifyX509 serverKey exact
+      C.x509ToPublic (pubKey, []) >>= C.pubKey
+
+-- consider how to process slow responses - is it handled somehow locally or delegated to the caller
+-- this method is used in the client
+-- sends PFWD :: C.PublicKeyX25519 -> EncTransmission -> Command Sender
+-- receives PRES :: EncResponse -> BrokerMsg -- proxy to client
+proxySMPMessage ::
+  SMPClient ->
+  -- proxy session from PKEY
+  SessionId ->
+  VersionSMP ->
+  C.PublicKeyX25519 ->
+  -- message to deliver
+  Maybe SndPrivateAuthKey ->
+  SenderId ->
+  MsgFlags ->
+  MsgBody ->
+  ExceptT SMPClientError IO ()
+-- TODO use version
+proxySMPMessage c@ProtocolClient {thParams = proxyThParams, client_ = PClient {clientCorrId = g}} sessionId _v serverKey spKey sId flags msg = do
+  -- prepare params
+  let serverThAuth = (\ta -> ta {serverPeerPubKey = serverKey}) <$> thAuth proxyThParams
+      serverThParams = proxyThParams {sessionId, thAuth = serverThAuth}
+  (cmdPubKey, cmdPrivKey) <- liftIO . atomically $ C.generateKeyPair @'C.X25519 g
+  let cmdSecret = C.dh' serverKey cmdPrivKey
+  nonce@(C.CbNonce corrId) <- liftIO . atomically $ C.randomCbNonce g
+  -- encode
+  let TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth serverThParams (CorrId corrId, sId, Cmd SSender $ SEND flags msg)
+  auth <- liftEitherWith PCETransportError $ authTransmission serverThAuth spKey nonce tForAuth
+  b <- case batchTransmissions (batch serverThParams) (blockSize serverThParams) [Right (auth, tToSend)] of
+    [] -> throwE $ PCETransportError TELargeMsg -- some other error. Internal?
+    TBError e _ : _ -> throwE $ PCETransportError e -- large message error?
+    TBTransmission s _ : _ -> pure s
+    TBTransmissions s _ _ : _ -> pure s
+  et <- liftEitherWith PCECryptoError $ EncTransmission <$> C.cbEncrypt cmdSecret nonce b paddedProxiedMsgLength
+  sendProtocolCommand_ c (Just nonce) Nothing sessionId (Cmd SProxiedClient (PFWD cmdPubKey et)) >>= \case
+    -- TODO support PKEY + resend?
+    PRES (EncResponse er) -> do
+      t' <- liftEitherWith PCECryptoError $ C.cbDecrypt cmdSecret (C.reverseNonce nonce) er
+      case tParse proxyThParams t' of
+        t'' :| [] -> case tDecodeParseValidate proxyThParams t'' of
+          (_auth, _signed, (_c, _e, r)) -> case r of -- TODO: verify
+            Left e -> throwE $ PCEResponseError e
+            Right OK -> pure ()
+            Right (ERR e) -> throwE $ PCEProtocolError e
+            Right u -> throwE . PCEUnexpectedResponse $ bshow u -- possibly differentiate unexpected response from server/proxy
+        _ -> throwE $ PCETransportError TEBadBlock
+    r -> throwE . PCEUnexpectedResponse $ bshow r -- from proxy
+
+-- this method is used in the proxy
+-- sends RFWD :: EncFwdTransmission -> Command Sender
+-- receives RRES :: EncFwdResponse -> BrokerMsg
+-- proxy should send PRES to the client with EncResponse
+forwardSMPMessage :: SMPClient -> CorrId -> C.PublicKeyX25519 -> EncTransmission -> ExceptT SMPClientError IO EncResponse
+forwardSMPMessage c@ProtocolClient {thParams, client_ = PClient {clientCorrId = g}} fwdCorrId fwdKey fwdTransmission = do
+  -- prepare params
+  sessSecret <- case thAuth thParams of
+    Nothing -> throwError $ PCEProtocolError INTERNAL -- different error - proxy didn't pass key?
+    Just THAuthClient {sessSecret} -> maybe (throwError $ PCEProtocolError INTERNAL) pure sessSecret
+  nonce <- liftIO . atomically $ C.randomCbNonce g
+  -- wrap
+  let fwdT = FwdTransmission {fwdCorrId, fwdKey, fwdTransmission}
+  eft <- liftEitherWith PCECryptoError $ EncFwdTransmission <$> C.cbEncrypt sessSecret nonce (smpEncode fwdT) paddedForwardedMsgLength
+  -- send
+  sendProtocolCommand_ c (Just nonce) Nothing "" (Cmd SSender (RFWD eft)) >>= \case
+    RRES (EncFwdResponse efr) -> do
+      -- unwrap
+      r' <- liftEitherWith PCECryptoError $ C.cbDecrypt sessSecret (C.reverseNonce nonce) efr
+      FwdResponse {fwdCorrId = _, fwdResponse} <- liftEitherWith (const $ PCEResponseError BLOCK) $ smpDecode r'
+      pure fwdResponse
+    r -> throwE . PCEUnexpectedResponse $ bshow r
+
 okSMPCommand :: PartyI p => Command p -> SMPClient -> C.APrivateAuthKey -> QueueId -> ExceptT SMPClientError IO ()
 okSMPCommand cmd c pKey qId =
  sendSMPCommand c (Just pKey) qId cmd >>= \case
@@ -710,26 +789,27 @@ streamProtocolCommands c@ProtocolClient {thParams = THandleParams {batch, blockS
  mapM_ (cb <=< sendBatch c) bs

 sendBatch :: ProtocolClient v err msg -> TransportBatch (Request err msg) -> IO [Response err msg]
-sendBatch c@ProtocolClient {client_ = PClient {rcvConcurrency, sndQ}} b = do
+sendBatch c@ProtocolClient {client_ = PClient {sndQ}} b = do
  case b of
    TBError e Request {entityId} -> do
      putStrLn "send error: large message"
      pure [Response entityId $ Left $ PCETransportError e]
    TBTransmissions s n rs
      | n > 0 -> do
-          active <- newTVarIO True
-          atomically $ writeTBQueue sndQ (active, s)
-          mapConcurrently (getResponse c active) rs
+          atomically $ writeTBQueue sndQ s
+          mapConcurrently (getResponse c) rs
      | otherwise -> pure []
    TBTransmission s r -> do
-      active <- newTVarIO True
-      atomically $ writeTBQueue sndQ (active, s)
-      (: []) <$> getResponse c active r
+      atomically $ writeTBQueue sndQ s
+      (: []) <$> getResponse c r

 -- | Send Protocol command
 sendProtocolCommand :: forall v err msg. ProtocolEncoding v err (ProtoCommand msg) => ProtocolClient v err msg -> Maybe C.APrivateAuthKey -> EntityId -> ProtoCommand msg -> ExceptT (ProtocolClientError err) IO msg
-sendProtocolCommand c@ProtocolClient {client_ = PClient {sndQ}, thParams = THandleParams {batch, blockSize}} pKey entId cmd =
-  ExceptT $ uncurry sendRecv =<< mkTransmission c (pKey, entId, cmd)
+sendProtocolCommand c = sendProtocolCommand_ c Nothing
+
+sendProtocolCommand_ :: forall v err msg. ProtocolEncoding v err (ProtoCommand msg) => ProtocolClient v err msg -> Maybe C.CbNonce -> Maybe C.APrivateAuthKey -> EntityId -> ProtoCommand msg -> ExceptT (ProtocolClientError err) IO msg
+sendProtocolCommand_ c@ProtocolClient {client_ = PClient {sndQ}, thParams = THandleParams {batch, blockSize}} nonce_ pKey entId cmd =
+  ExceptT $ uncurry sendRecv =<< mkTransmission_ c nonce_ (pKey, entId, cmd)
  where
    -- two separate "atomically" needed to avoid blocking
    sendRecv :: Either TransportError SentRawTransmission -> Request err msg -> IO (Either (ProtocolClientError err) msg)
@@ -737,50 +817,46 @@ sendProtocolCommand c@ProtocolClient {client_ = PClient {sndQ}, thParams = THand
      Left e -> pure . Left $ PCETransportError e
      Right t
        | B.length s > blockSize - 2 -> pure . Left $ PCETransportError TELargeMsg
-        | otherwise -> do
-            active <- newTVarIO True
-            atomically (writeTBQueue sndQ (active, s))
-            response <$> getResponse c active r
+        | otherwise -> atomically (writeTBQueue sndQ s) >> response <$> getResponse c r
        where
          s
            | batch = tEncodeBatch1 t
            | otherwise = tEncode t

 -- TODO switch to timeout or TimeManager that supports Int64
-getResponse :: ProtocolClient v err msg -> TVar Bool -> Request err msg -> IO (Response err msg)
-getResponse ProtocolClient {client_ = PClient {tcpTimeout, timeoutErrorCount, sentCommands}} active Request {corrId, entityId, responseVar} = do
+getResponse :: ProtocolClient v err msg -> Request err msg -> IO (Response err msg)
+getResponse ProtocolClient {client_ = PClient {tcpTimeout, pingErrorCount}} Request {entityId, responseVar} = do
  response <-
    timeout tcpTimeout (atomically (takeTMVar responseVar)) >>= \case
-      Just r -> atomically (writeTVar timeoutErrorCount 0) $> r
-      Nothing -> do
-        atomically (writeTVar active False >> TM.delete corrId sentCommands)
-        atomically $ modifyTVar' timeoutErrorCount (+ 1)
-        pure $ Left PCEResponseTimeout
+      -- BTW: another registerDelay candidate. Also, crashes caller with BlockedIndef.
+      Just r -> atomically (writeTVar pingErrorCount 0) $> r
+      Nothing -> pure $ Left PCEResponseTimeout
  pure Response {entityId, response}

-mkTransmission :: forall v err msg. ProtocolEncoding v err (ProtoCommand msg) => ProtocolClient v err msg -> ClientCommand msg -> IO (PCTransmission err msg)
-mkTransmission ProtocolClient {thParams, client_ = PClient {clientCorrId, sentCommands}} (pKey_, entId, cmd) = do
-  corrId <- atomically getNextCorrId
-  let TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth thParams (corrId, entId, cmd)
-      auth = authTransmission (thAuth thParams) pKey_ corrId tForAuth
-  r <- atomically $ mkRequest corrId
+mkTransmission :: ProtocolEncoding v err (ProtoCommand msg) => ProtocolClient v err msg -> ClientCommand msg -> IO (PCTransmission err msg)
+mkTransmission c = mkTransmission_ c Nothing
+
+mkTransmission_ :: forall v err msg. ProtocolEncoding v err (ProtoCommand msg) => ProtocolClient v err msg -> Maybe C.CbNonce -> ClientCommand msg -> IO (PCTransmission err msg)
+mkTransmission_ ProtocolClient {thParams, client_ = PClient {clientCorrId, sentCommands}} nonce_ (pKey_, entId, cmd) = do
+  nonce@(C.CbNonce corrId) <- maybe (atomically $ C.randomCbNonce clientCorrId) pure nonce_
+  let TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth thParams (CorrId corrId, entId, cmd)
+      auth = authTransmission (thAuth thParams) pKey_ nonce tForAuth
+  r <- atomically $ mkRequest (CorrId corrId)
  pure ((,tToSend) <$> auth, r)
  where
-    getNextCorrId :: STM CorrId
-    getNextCorrId = CorrId <$> C.randomBytes 24 clientCorrId -- also used as nonce
    mkRequest :: CorrId -> STM (Request err msg)
    mkRequest corrId = do
-      r <- Request corrId entId <$> newEmptyTMVar
+      r <- Request entId <$> newEmptyTMVar
      TM.insert corrId r sentCommands
      pure r

-authTransmission :: Maybe (THandleAuth 'TClient) -> Maybe C.APrivateAuthKey -> CorrId -> ByteString -> Either TransportError (Maybe TransmissionAuth)
-authTransmission thAuth pKey_ (CorrId corrId) t = traverse authenticate pKey_
+authTransmission :: Maybe (THandleAuth 'TClient) -> Maybe C.APrivateAuthKey -> C.CbNonce -> ByteString -> Either TransportError (Maybe TransmissionAuth)
+authTransmission thAuth pKey_ nonce t = traverse authenticate pKey_
  where
    authenticate :: C.APrivateAuthKey -> Either TransportError TransmissionAuth
    authenticate (C.APrivateAuthKey a pk) = case a of
      C.SX25519 -> case thAuth of
-        Just THAuthClient {serverPeerPubKey = k} -> Right $ TAAuthenticator $ C.cbAuthenticate k pk (C.cbNonce corrId) t
+        Just THAuthClient {serverPeerPubKey = k} -> Right $ TAAuthenticator $ C.cbAuthenticate k pk nonce t
        Nothing -> Left TENoServerAuth
      C.SEd25519 -> sign pk
      C.SEd448 -> sign pk
@@ -8,6 +8,7 @@
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TupleSections #-}
 {-# LANGUAGE TypeApplications #-}
+{-# OPTIONS_GHC -fno-warn-orphans #-}

 module Simplex.Messaging.Client.Agent where

@@ -18,6 +19,7 @@ import Control.Monad
 import Control.Monad.Except
 import Control.Monad.IO.Unlift
 import Control.Monad.Trans.Except
+import Control.Monad.Trans.Reader
 import Crypto.Random (ChaChaDRG)
 import Data.Bifunctor (bimap, first)
 import Data.ByteString.Char8 (ByteString)
@@ -45,6 +47,8 @@ import Simplex.Messaging.Transport
 import Simplex.Messaging.Util (catchAll_, toChunks, ($>>=))
 import System.Timeout (timeout)
 import UnliftIO (async)
+import UnliftIO.Exception (Exception)
+import qualified UnliftIO.Exception as E
 import UnliftIO.STM

 type SMPClientVar = SessionVar (Either SMPClientError SMPClient)
@@ -94,6 +98,7 @@ data SMPClientAgent = SMPClientAgent
    agentQ :: TBQueue SMPClientAgentEvent,
    randomDrg :: TVar ChaChaDRG,
    smpClients :: TMap SMPServer SMPClientVar,
+    smpSessions :: TMap SessionId SMPClient,
    srvSubs :: TMap SMPServer (TMap SMPSub C.APrivateAuthKey),
    pendingSrvSubs :: TMap SMPServer (TMap SMPSub C.APrivateAuthKey),
    reconnections :: TVar [Async ()],
@@ -101,11 +106,37 @@ data SMPClientAgent = SMPClientAgent
    workerSeq :: TVar Int
  }

+newtype InternalException e = InternalException {unInternalException :: e}
+  deriving (Eq, Show)
+
+instance Exception e => Exception (InternalException e)
+
+instance Exception e => MonadUnliftIO (ExceptT e IO) where
+  {-# INLINE withRunInIO #-}
+  withRunInIO :: ((forall a. ExceptT e IO a -> IO a) -> IO b) -> ExceptT e IO b
+  withRunInIO inner =
+    ExceptT . fmap (first unInternalException) . E.try $
+      withRunInIO $ \run ->
+        inner $ run . (either (E.throwIO . InternalException) pure <=< runExceptT)
+
+-- as MonadUnliftIO instance for IO is `withRunInIO inner = inner id`,
+-- the last two lines could be replaced with:
+-- inner $ either (E.throwIO . InternalException) pure <=< runExceptT
+
+instance Exception e => MonadUnliftIO (ExceptT e (ReaderT r IO)) where
+  {-# INLINE withRunInIO #-}
+  withRunInIO :: ((forall a. ExceptT e (ReaderT r IO) a -> IO a) -> IO b) -> ExceptT e (ReaderT r IO) b
+  withRunInIO inner =
+    withExceptT unInternalException . ExceptT . E.try $
+      withRunInIO $ \run ->
+        inner $ run . (either (E.throwIO . InternalException) pure <=< runExceptT)
+
 newSMPClientAgent :: SMPClientAgentConfig -> TVar ChaChaDRG -> STM SMPClientAgent
 newSMPClientAgent agentCfg@SMPClientAgentConfig {msgQSize, agentQSize} randomDrg = do
  msgQ <- newTBQueue msgQSize
  agentQ <- newTBQueue agentQSize
  smpClients <- TM.empty
+  smpSessions <- TM.empty
  srvSubs <- TM.empty
  pendingSrvSubs <- TM.empty
  reconnections <- newTVar []
@@ -118,6 +149,7 @@ newSMPClientAgent agentCfg@SMPClientAgentConfig {msgQSize, agentQSize} randomDrg
        agentQ,
        randomDrg,
        smpClients,
+        smpSessions,
        srvSubs,
        pendingSrvSubs,
        reconnections,
@@ -126,7 +158,7 @@ newSMPClientAgent agentCfg@SMPClientAgentConfig {msgQSize, agentQSize} randomDrg
      }

 getSMPServerClient' :: SMPClientAgent -> SMPServer -> ExceptT SMPClientError IO SMPClient
-getSMPServerClient' ca@SMPClientAgent {agentCfg, smpClients, msgQ, randomDrg, workerSeq} srv =
+getSMPServerClient' ca@SMPClientAgent {agentCfg, smpClients, smpSessions, msgQ, randomDrg, workerSeq} srv =
  atomically getClientVar >>= either newSMPClient waitForSMPClient
  where
    getClientVar :: STM (Either SMPClientVar SMPClientVar)
@@ -149,7 +181,9 @@ getSMPServerClient' ca@SMPClientAgent {agentCfg, smpClients, msgQ, randomDrg, wo
          tryE (connectClient v) >>= \r -> case r of
            Right smp -> do
              logInfo . decodeUtf8 $ "Agent connected to " <> showServer srv
-              atomically $ putTMVar (sessionVar v) r
+              atomically $ do
+                putTMVar (sessionVar v) r
+                TM.insert (sessionId $ thParams smp) smp smpSessions
              successAction smp
            Left e -> do
              if e == PCENetworkError || e == PCEResponseTimeout
@@ -171,13 +205,14 @@ getSMPServerClient' ca@SMPClientAgent {agentCfg, smpClients, msgQ, randomDrg, wo
    connectClient v = ExceptT $ getProtocolClient randomDrg (1, srv, Nothing) (smpCfg agentCfg) (Just msgQ) (clientDisconnected v)

    clientDisconnected :: SMPClientVar -> SMPClient -> IO ()
-    clientDisconnected v _ = do
-      removeClientAndSubs v >>= (`forM_` serverDown)
+    clientDisconnected v smp = do
+      removeClientAndSubs v smp >>= (`forM_` serverDown)
      logInfo . decodeUtf8 $ "Agent disconnected from " <> showServer srv

-    removeClientAndSubs :: SMPClientVar -> IO (Maybe (Map SMPSub C.APrivateAuthKey))
-    removeClientAndSubs v = atomically $ do
+    removeClientAndSubs :: SMPClientVar -> SMPClient -> IO (Maybe (Map SMPSub C.APrivateAuthKey))
+    removeClientAndSubs v smp = atomically $ do
      removeSessVar v srv smpClients
+      TM.delete (sessionId $ thParams smp) smpSessions
      TM.lookupDelete srv (srvSubs ca) >>= mapM updateSubs
      where
        updateSubs sVar = do
@@ -242,6 +277,9 @@ getSMPServerClient' ca@SMPClientAgent {agentCfg, smpClients, msgQ, randomDrg, wo
    notify :: SMPClientAgentEvent -> IO ()
    notify evt = atomically $ writeTBQueue (agentQ ca) evt

+lookupSMPServerClient :: SMPClientAgent -> SessionId -> STM (Maybe SMPClient)
+lookupSMPServerClient SMPClientAgent {smpSessions} sessId = TM.lookup sessId smpSessions
+
 closeSMPClientAgent :: SMPClientAgent -> IO ()
 closeSMPClientAgent c = do
  closeSMPServerClients c
@@ -4,9 +4,20 @@
 module Simplex.Messaging.Compression where

 import qualified Codec.Compression.Zstd as Z1
+import qualified Codec.Compression.Zstd.FFI as Z
+import Control.Monad (forM)
+import Control.Monad.Except
+import Control.Monad.IO.Class
 import Data.ByteString (ByteString)
 import qualified Data.ByteString as B
+import qualified Data.ByteString.Unsafe as B
+import Data.Either (fromRight)
+import Data.List.NonEmpty (NonEmpty)
+import Foreign
+import Foreign.C.Types
+import GHC.IO (unsafePerformIO)
 import Simplex.Messaging.Encoding
+import UnliftIO.Exception (bracket)

 data Compressed
  = -- | Short messages are left intact to skip copying and FFI festivities.
@@ -31,15 +42,49 @@ instance Encoding Compressed where
      '1' -> Compressed <$> smpP
      x -> fail $ "unknown Compressed tag: " <> show x

+-- | Compress as single chunk using stack-allocated context.
 compress1 :: ByteString -> Compressed
 compress1 bs
  | B.length bs <= maxLengthPassthrough = Passthrough bs
  | otherwise = Compressed . Large $ Z1.compress compressionLevel bs

-decompress1 :: Compressed -> Either String ByteString
-decompress1 = \case
-  Passthrough bs -> Right bs
-  Compressed (Large bs) -> case Z1.decompress bs of
-    Z1.Error e -> Left e
-    Z1.Skip -> Right mempty
-    Z1.Decompress bs' -> Right bs'
+type CompressCtx = (Ptr Z.CCtx, Ptr CChar, CSize)
+
+withCompressCtx :: CSize -> (CompressCtx -> IO a) -> IO a
+withCompressCtx scratchSize action =
+  bracket Z.createCCtx Z.freeCCtx $ \cctx ->
+    allocaBytes (fromIntegral scratchSize) $ \scratchPtr ->
+      action (cctx, scratchPtr, scratchSize)
+
+-- | Compress bytes, falling back to Passthrough in case of some internal error.
+compress :: CompressCtx -> ByteString -> IO Compressed
+compress ctx bs = fromRight (Passthrough bs) <$> compress_ ctx bs
+
+compress_ :: CompressCtx -> ByteString -> IO (Either String Compressed)
+compress_ (cctx, scratchPtr, scratchSize) bs
+  | B.length bs <= maxLengthPassthrough = pure . Right $ Passthrough bs
+  | otherwise =
+      B.unsafeUseAsCStringLen bs $ \(sourcePtr, sourceSize) -> runExceptT $ do
+        -- should not fail, unless input buffer is too short
+        dstSize <- ExceptT $ Z.checkError $ Z.compressCCtx cctx scratchPtr scratchSize sourcePtr (fromIntegral sourceSize) compressionLevel
+        liftIO $ Compressed . Large <$> B.packCStringLen (scratchPtr, fromIntegral dstSize)
+
+type DecompressCtx = (Ptr Z.DCtx, Ptr CChar, CSize)
+
+withDecompressCtx :: Int -> (DecompressCtx -> IO a) -> IO a
+withDecompressCtx maxUnpackedSize action =
+  bracket Z.createDCtx Z.freeDCtx $ \dctx ->
+    allocaBytes maxUnpackedSize $ \scratchPtr ->
+      action (dctx, scratchPtr, fromIntegral maxUnpackedSize)
+
+decompress :: DecompressCtx -> Compressed -> IO (Either String ByteString)
+decompress (dctx, scratchPtr, scratchSize) = \case
+  Passthrough bs -> pure $ Right bs
+  Compressed (Large bs) ->
+    B.unsafeUseAsCStringLen bs $ \(sourcePtr, sourceSize) -> do
+      res <- Z.checkError $ Z.decompressDCtx dctx scratchPtr scratchSize sourcePtr (fromIntegral sourceSize)
+      forM res $ \dstSize -> B.packCStringLen (scratchPtr, fromIntegral dstSize)
+
+decompressBatch :: Int -> NonEmpty Compressed -> NonEmpty (Either String ByteString)
+decompressBatch maxUnpackedSize items = unsafePerformIO $ withDecompressCtx maxUnpackedSize $ forM items . decompress
+{-# NOINLINE decompressBatch #-} -- prevent double-evaluation under unsafePerformIO
@@ -141,6 +141,7 @@ module Simplex.Messaging.Crypto
    sbEncrypt_,
    cbNonce,
    randomCbNonce,
+    reverseNonce,

    -- * NaCl crypto_secretbox
    SbKey (unSbKey),
@@ -756,6 +757,8 @@ data Signature (a :: Algorithm) where
  SignatureEd25519 :: Ed25519.Signature -> Signature Ed25519
  SignatureEd448 :: Ed448.Signature -> Signature Ed448

+deriving instance Eq (Signature a)
+
 deriving instance Show (Signature a)

 data ASignature
@@ -1290,6 +1293,9 @@ randomCbNonce = fmap CryptoBoxNonce . randomBytes 24
 randomBytes :: Int -> TVar ChaChaDRG -> STM ByteString
 randomBytes n gVar = stateTVar gVar $ randomBytesGenerate n

+reverseNonce :: CbNonce -> CbNonce
+reverseNonce (CryptoBoxNonce s) = CryptoBoxNonce (B.reverse s)
+
 instance Encoding CbNonce where
  smpEncode = unCbNonce
  smpP = CryptoBoxNonce <$> A.take 24
@@ -31,6 +31,7 @@ import qualified Data.ByteString.Char8 as B
 import qualified Data.ByteString.Lazy as LB
 import Data.List.NonEmpty (NonEmpty (..))
 import Data.Maybe (isJust)
+import Simplex.Messaging.Client.Agent ()
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Crypto.Lazy (LazyByteString)
 import qualified Simplex.Messaging.Crypto.Lazy as LC
@@ -143,11 +143,16 @@ kdfX3DHE2EEncryptVersion = VersionE2E 2
 pqRatchetE2EEncryptVersion :: VersionE2E
 pqRatchetE2EEncryptVersion = VersionE2E 3

+-- TODO v5.7 increase to 3
 currentE2EEncryptVersion :: VersionE2E
-currentE2EEncryptVersion = VersionE2E 3
+currentE2EEncryptVersion = VersionE2E 2

-supportedE2EEncryptVRange :: VersionRangeE2E
-supportedE2EEncryptVRange = mkVersionRange kdfX3DHE2EEncryptVersion currentE2EEncryptVersion
+-- TODO v5.7 remove dependency of version range on whether PQ encryption is used
+supportedE2EEncryptVRange :: PQSupport -> VersionRangeE2E
+supportedE2EEncryptVRange pq =
+  mkVersionRange kdfX3DHE2EEncryptVersion $ case pq of 
+    PQSupportOn -> pqRatchetE2EEncryptVersion
+    PQSupportOff -> currentE2EEncryptVersion

 data RatchetKEMState
  = RKSProposed -- only KEM encapsulation key
@@ -75,6 +75,8 @@ instance StrEncoding Str where
  strEncode = unStr
  strP = Str <$> A.takeTill (== ' ') <* optional A.space

+-- inherited from ByteString, the parser only allows non-empty strings
+-- only Char8 elements may round-trip as B.pack truncates unicode
 instance StrEncoding String where
  strEncode = strEncode . B.pack
  strP = B.unpack <$> strP
@@ -10,7 +10,7 @@ import Data.Word (Word16)
 import Simplex.Messaging.Client
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Notifications.Protocol
-import Simplex.Messaging.Notifications.Transport (NTFVersion, supportedClientNTFVRange, supportedNTFHandshakes)
+import Simplex.Messaging.Notifications.Transport (NTFVersion, supportedClientNTFVRange)
 import Simplex.Messaging.Protocol (ErrorType)
 import Simplex.Messaging.Util (bshow)

@@ -19,7 +19,7 @@ type NtfClient = ProtocolClient NTFVersion ErrorType NtfResponse
 type NtfClientError = ProtocolClientError ErrorType

 defaultNTFClientConfig :: ProtocolClientConfig NTFVersion
-defaultNTFClientConfig = defaultClientConfig (Just supportedNTFHandshakes) supportedClientNTFVRange
+defaultNTFClientConfig = defaultClientConfig supportedClientNTFVRange

 ntfRegisterToken :: NtfClient -> C.APrivateAuthKey -> NewNtfEntity 'Token -> ExceptT NtfClientError IO (NtfTokenId, C.PublicKeyX25519)
 ntfRegisterToken c pKey newTkn =
@@ -218,7 +218,7 @@ ntfSubscriber NtfSubscriber {smpSubscribers, newSubQ, smpAgent = ca@SMPClientAge

    receiveSMP :: M ()
    receiveSMP = forever $ do
-      ((_, srv, _), _, _, _, ntfId, msg) <- atomically $ readTBQueue msgQ
+      ((_, srv, _), _, _, ntfId, msg) <- atomically $ readTBQueue msgQ
      let smpQueue = SMPQueueNtf srv ntfId
      case msg of
        SMP.NMSG nmsgNonce encNMsgMeta -> do
@@ -34,7 +34,7 @@ import Simplex.Messaging.Server.Expiration
 import Simplex.Messaging.TMap (TMap)
 import qualified Simplex.Messaging.TMap as TM
 import Simplex.Messaging.Transport (ATransport, THandleParams, TransportPeer (..))
-import Simplex.Messaging.Transport.Server (TransportServerConfig, alpn, loadFingerprint, loadTLSServerParams)
+import Simplex.Messaging.Transport.Server (TransportServerConfig, loadFingerprint, loadTLSServerParams)
 import System.IO (IOMode (..))
 import System.Mem.Weak (Weak)
 import UnliftIO.STM
@@ -84,7 +84,7 @@ data NtfEnv = NtfEnv
  }

 newNtfServerEnv :: NtfServerConfig -> IO NtfEnv
-newNtfServerEnv config@NtfServerConfig {subQSize, pushQSize, smpAgentCfg, apnsConfig, storeLogFile, caCertificateFile, certificateFile, privateKeyFile, transportConfig} = do
+newNtfServerEnv config@NtfServerConfig {subQSize, pushQSize, smpAgentCfg, apnsConfig, storeLogFile, caCertificateFile, certificateFile, privateKeyFile} = do
  random <- liftIO C.newRandom
  store <- atomically newNtfStore
  logInfo "restoring subscriptions..."
@@ -92,7 +92,7 @@ newNtfServerEnv config@NtfServerConfig {subQSize, pushQSize, smpAgentCfg, apnsCo
  logInfo "restored subscriptions"
  subscriber <- atomically $ newNtfSubscriber subQSize smpAgentCfg random
  pushServer <- atomically $ newNtfPushServer pushQSize apnsConfig
-  tlsServerParams <- liftIO $ loadTLSServerParams caCertificateFile certificateFile privateKeyFile (alpn transportConfig)
+  tlsServerParams <- liftIO $ loadTLSServerParams caCertificateFile certificateFile privateKeyFile
  Fingerprint fp <- liftIO $ loadFingerprint caCertificateFile
  serverStats <- atomically . newNtfServerStats =<< liftIO getCurrentTime
  pure NtfEnv {config, subscriber, pushServer, store, storeLog, random, tlsServerParams, serverIdentity = C.KeyHash fp, serverStats}
@@ -18,7 +18,7 @@ import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Notifications.Server (runNtfServer)
 import Simplex.Messaging.Notifications.Server.Env (NtfServerConfig (..), defaultInactiveClientExpiration)
 import Simplex.Messaging.Notifications.Server.Push.APNS (defaultAPNSPushClientConfig)
-import Simplex.Messaging.Notifications.Transport (supportedNTFHandshakes, supportedServerNTFVRange)
+import Simplex.Messaging.Notifications.Transport (supportedServerNTFVRange)
 import Simplex.Messaging.Protocol (ProtoServerWithAuth (..), pattern NtfServer)
 import Simplex.Messaging.Server.CLI
 import Simplex.Messaging.Server.Expiration
@@ -133,8 +133,7 @@ ntfServerCLI cfgPath logPath =
              ntfServerVRange = supportedServerNTFVRange,
              transportConfig =
                defaultTransportServerConfig
-                  { logTLSErrors = fromMaybe False $ iniOnOff "TRANSPORT" "log_tls_errors" ini,
-                    alpn = Just supportedNTFHandshakes
+                  { logTLSErrors = fromMaybe False $ iniOnOff "TRANSPORT" "log_tls_errors" ini
                  }
            }

@@ -44,23 +44,17 @@ authBatchCmdsNTFVersion :: VersionNTF
 authBatchCmdsNTFVersion = VersionNTF 2

 currentClientNTFVersion :: VersionNTF
-currentClientNTFVersion = VersionNTF 2
+currentClientNTFVersion = VersionNTF 1

 currentServerNTFVersion :: VersionNTF
-currentServerNTFVersion = VersionNTF 2
+currentServerNTFVersion = VersionNTF 1

 supportedClientNTFVRange :: VersionRangeNTF
 supportedClientNTFVRange = mkVersionRange initialNTFVersion currentClientNTFVersion

-legacyServerNTFVRange :: VersionRangeNTF
-legacyServerNTFVRange = mkVersionRange initialNTFVersion initialNTFVersion
-
 supportedServerNTFVRange :: VersionRangeNTF
 supportedServerNTFVRange = mkVersionRange initialNTFVersion currentServerNTFVersion

-supportedNTFHandshakes :: [ALPN]
-supportedNTFHandshakes = ["ntf/1"]
-
 type THandleNTF c p = THandle NTFVersion c p

 data NtfServerHandshake = NtfServerHandshake
@@ -110,13 +104,12 @@ ntfServerHandshake :: forall c. Transport c => C.APrivateSignKey -> c -> C.KeyPa
 ntfServerHandshake serverSignKey c (k, pk) kh ntfVRange = 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}
+  sendHandshake th $ NtfServerHandshake {sessionId, ntfVersionRange = ntfVRange, authPubKey = Just sk}
  getHandshake th >>= \case
    NtfClientHandshake {ntfVersion = v, keyHash}
      | keyHash /= kh ->
          throwError $ TEHandshake IDENTITY
-      | v `isCompatible` ntfVersionRange ->
+      | v `isCompatible` ntfVRange ->
          pure $ ntfThHandleServer th v pk
      | otherwise -> throwError $ TEHandshake VERSION

@@ -43,6 +43,8 @@ module Simplex.Messaging.Protocol
  ( -- * SMP protocol parameters
    supportedSMPClientVRange,
    maxMessageLength,
+    paddedProxiedMsgLength,
+    paddedForwardedMsgLength,
    e2eEncConfirmationLength,
    e2eEncMessageLength,

@@ -56,6 +58,7 @@ module Simplex.Messaging.Protocol
    SubscriptionMode (..),
    Party (..),
    Cmd (..),
+    DirectParty,
    BrokerMsg (..),
    SParty (..),
    PartyI (..),
@@ -63,6 +66,7 @@ module Simplex.Messaging.Protocol
    ProtocolErrorType (..),
    ErrorType (..),
    CommandError (..),
+    ProxyError (..),
    Transmission,
    TransmissionAuth (..),
    SignedTransmission,
@@ -121,6 +125,12 @@ module Simplex.Messaging.Protocol
    EncNMsgMeta,
    SMPMsgMeta (..),
    NMsgMeta (..),
+    EncFwdResponse (..),
+    EncFwdTransmission (..),
+    EncResponse (..),
+    EncTransmission (..),
+    FwdResponse (..),
+    FwdTransmission (..),
    MsgFlags (..),
    initialSMPClientVersion,
    userProtocol,
@@ -185,10 +195,15 @@ import Data.List.NonEmpty (NonEmpty (..))
 import qualified Data.List.NonEmpty as L
 import Data.Maybe (isJust, isNothing)
 import Data.String
+import qualified Data.Text as T
+import Data.Text.Encoding (encodeUtf8)
 import Data.Time.Clock.System (SystemTime (..))
 import Data.Type.Equality
 import Data.Word (Word16)
+import qualified Data.X509 as X
 import GHC.TypeLits (ErrorMessage (..), TypeError, type (+))
+import qualified GHC.TypeLits as TE
+import qualified GHC.TypeLits as Type
 import Network.Socket (ServiceName)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding
@@ -197,7 +212,7 @@ import Simplex.Messaging.Parsers
 import Simplex.Messaging.ServiceScheme
 import Simplex.Messaging.Transport
 import Simplex.Messaging.Transport.Client (TransportHost, TransportHosts (..))
-import Simplex.Messaging.Util (bshow, eitherToMaybe, (<$?>))
+import Simplex.Messaging.Util (bshow, eitherToMaybe, safeDecodeUtf8, (<$?>))
 import Simplex.Messaging.Version
 import Simplex.Messaging.Version.Internal

@@ -231,6 +246,20 @@ supportedSMPClientVRange = mkVersionRange initialSMPClientVersion currentSMPClie
 maxMessageLength :: Int
 maxMessageLength = 16088

+-- without signature works with min 16151 (fails with 16150)
+-- with Ed448: 16265 (fails with 16264)
+-- with Ed25519: 16215 (fails with 16214)
+-- with X25519: 16232 (fails with 16231)
+paddedProxiedMsgLength :: Int
+paddedProxiedMsgLength = 16232
+
+-- without signature works with min 16239 (fails with 16238)
+-- with Ed448: 16353 (fails with 16352)
+-- with Ed25519: 16303 (fails with 16302)
+-- with X25519: 16320 (fails with 16319)
+paddedForwardedMsgLength :: Int
+paddedForwardedMsgLength = 16320
+
 type MaxMessageLen = 16088

 -- 16 extra bytes: 8 for timestamp and 8 for flags (7 flags and the space, only 1 flag is currently used)
@@ -238,13 +267,13 @@ type MaxRcvMessageLen = MaxMessageLen + 16 -- 16104, the padded size is 16106

 -- it is shorter to allow per-queue e2e encryption DH key in the "public" header
 e2eEncConfirmationLength :: Int
-e2eEncConfirmationLength = 15920 -- 15881 .. 15976
+e2eEncConfirmationLength = 15936

 e2eEncMessageLength :: Int
-e2eEncMessageLength = 16016 -- 16004 .. 16021
+e2eEncMessageLength = 16032

 -- | SMP protocol clients
-data Party = Recipient | Sender | Notifier
+data Party = Recipient | Sender | Notifier | ProxiedClient
  deriving (Show)

 -- | Singleton types for SMP protocol clients
@@ -252,11 +281,13 @@ data SParty :: Party -> Type where
  SRecipient :: SParty Recipient
  SSender :: SParty Sender
  SNotifier :: SParty Notifier
+  SProxiedClient :: SParty ProxiedClient

 instance TestEquality SParty where
  testEquality SRecipient SRecipient = Just Refl
  testEquality SSender SSender = Just Refl
  testEquality SNotifier SNotifier = Just Refl
+  testEquality SProxiedClient SProxiedClient = Just Refl
  testEquality _ _ = Nothing

 deriving instance Show (SParty p)
@@ -269,6 +300,15 @@ instance PartyI Sender where sParty = SSender

 instance PartyI Notifier where sParty = SNotifier

+instance PartyI ProxiedClient where sParty = SProxiedClient
+
+type family DirectParty (p :: Party) :: Constraint where
+  DirectParty Recipient = ()
+  DirectParty Sender = ()
+  DirectParty Notifier = ()
+  DirectParty p =
+    (Int ~ Bool, TypeError (Type.Text "Party " :<>: ShowType p :<>: Type.Text " is not direct"))
+
 -- | Type for client command of any participant.
 data Cmd = forall p. PartyI p => Cmd (SParty p) (Command p)

@@ -359,6 +399,17 @@ data Command (p :: Party) where
  PING :: Command Sender
  -- SMP notification subscriber commands
  NSUB :: Command Notifier
+  PRXY :: SMPServer -> Maybe BasicAuth -> Command ProxiedClient -- request a relay server connection by URI
+  -- Transmission to proxy:
+  -- - entity ID: ID of the session with relay returned in PKEY (response to PRXY)
+  -- - corrId: also used as a nonce to encrypt transmission to relay, corrId + 1 - from relay
+  -- - key (1st param in the command) is used to agree DH secret for this particular transmission and its response
+  -- Encrypted transmission should include session ID (tlsunique) from proxy-relay connection.
+  PFWD :: C.PublicKeyX25519 -> EncTransmission -> Command ProxiedClient -- use CorrId as CbNonce, client to proxy
+  -- Transmission forwarded to relay:
+  -- - entity ID: empty
+  -- - corrId: unique correlation ID between proxy and relay, also used as a nonce to encrypt forwarded transmission
+  RFWD :: EncFwdTransmission -> Command Sender -- use CorrId as CbNonce, proxy to relay

 deriving instance Show (Command p)

@@ -384,6 +435,25 @@ instance Encoding SubscriptionMode where
      'C' -> pure SMOnlyCreate
      _ -> fail "bad SubscriptionMode"

+newtype EncTransmission = EncTransmission ByteString
+  deriving (Show)
+
+data FwdTransmission = FwdTransmission
+  { fwdCorrId :: CorrId,
+    fwdKey :: C.PublicKeyX25519,
+    fwdTransmission :: EncTransmission
+  }
+
+instance Encoding FwdTransmission where
+  smpEncode FwdTransmission {fwdCorrId = CorrId corrId, fwdKey, fwdTransmission = EncTransmission t} =
+    smpEncode (corrId, fwdKey, Tail t)
+  smpP = do
+    (corrId, fwdKey, Tail t) <- smpP
+    pure FwdTransmission {fwdCorrId = CorrId corrId, fwdKey, fwdTransmission = EncTransmission t}
+
+newtype EncFwdTransmission = EncFwdTransmission ByteString
+  deriving (Show)
+
 data BrokerMsg where
  -- SMP broker messages (responses, client messages, notifications)
  IDS :: QueueIdsKeys -> BrokerMsg
@@ -393,6 +463,10 @@ data BrokerMsg where
  MSG :: RcvMessage -> BrokerMsg
  NID :: NotifierId -> RcvNtfPublicDhKey -> BrokerMsg
  NMSG :: C.CbNonce -> EncNMsgMeta -> BrokerMsg
+  -- Should include certificate chain
+  PKEY :: SessionId -> VersionRangeSMP -> (X.CertificateChain, X.SignedExact X.PubKey) -> BrokerMsg -- TLS-signed server key for proxy shared secret and initial sender key
+  RRES :: EncFwdResponse -> BrokerMsg -- relay to proxy
+  PRES :: EncResponse -> BrokerMsg -- proxy to client
  END :: BrokerMsg
  OK :: BrokerMsg
  ERR :: ErrorType -> BrokerMsg
@@ -405,6 +479,24 @@ data RcvMessage = RcvMessage
  }
  deriving (Eq, Show)

+newtype EncFwdResponse = EncFwdResponse ByteString
+  deriving (Eq, Show)
+
+data FwdResponse = FwdResponse
+  { fwdCorrId :: CorrId,
+    fwdResponse :: EncResponse
+  }
+
+instance Encoding FwdResponse where
+  smpEncode FwdResponse {fwdCorrId = CorrId corrId, fwdResponse = EncResponse t} =
+    smpEncode (corrId, Tail t)
+  smpP = do
+    (corrId, Tail t) <- smpP
+    pure FwdResponse {fwdCorrId = CorrId corrId, fwdResponse = EncResponse t}
+
+newtype EncResponse = EncResponse ByteString
+  deriving (Eq, Show)
+
 -- | received message without server/recipient encryption
 data Message
  = Message
@@ -567,6 +659,9 @@ data CommandTag (p :: Party) where
  DEL_ :: CommandTag Recipient
  SEND_ :: CommandTag Sender
  PING_ :: CommandTag Sender
+  PRXY_ :: CommandTag ProxiedClient
+  PFWD_ :: CommandTag ProxiedClient
+  RFWD_ :: CommandTag Sender
  NSUB_ :: CommandTag Notifier

 data CmdTag = forall p. PartyI p => CT (SParty p) (CommandTag p)
@@ -580,6 +675,9 @@ data BrokerMsgTag
  | MSG_
  | NID_
  | NMSG_
+  | PKEY_
+  | RRES_
+  | PRES_
  | END_
  | OK_
  | ERR_
@@ -607,6 +705,9 @@ instance PartyI p => Encoding (CommandTag p) where
    DEL_ -> "DEL"
    SEND_ -> "SEND"
    PING_ -> "PING"
+    PRXY_ -> "PRXY"
+    PFWD_ -> "PFWD"
+    RFWD_ -> "RFWD"
    NSUB_ -> "NSUB"
  smpP = messageTagP

@@ -623,6 +724,9 @@ instance ProtocolMsgTag CmdTag where
    "DEL" -> Just $ CT SRecipient DEL_
    "SEND" -> Just $ CT SSender SEND_
    "PING" -> Just $ CT SSender PING_
+    "PRXY" -> Just $ CT SProxiedClient PRXY_
+    "PFWD" -> Just $ CT SProxiedClient PFWD_
+    "RFWD" -> Just $ CT SSender RFWD_
    "NSUB" -> Just $ CT SNotifier NSUB_
    _ -> Nothing

@@ -639,6 +743,9 @@ instance Encoding BrokerMsgTag where
    MSG_ -> "MSG"
    NID_ -> "NID"
    NMSG_ -> "NMSG"
+    PKEY_ -> "PKEY"
+    RRES_ -> "RRES"
+    PRES_ -> "PRES"
    END_ -> "END"
    OK_ -> "OK"
    ERR_ -> "ERR"
@@ -651,6 +758,9 @@ instance ProtocolMsgTag BrokerMsgTag where
    "MSG" -> Just MSG_
    "NID" -> Just NID_
    "NMSG" -> Just NMSG_
+    "PKEY" -> Just PKEY_
+    "RRES" -> Just RRES_
+    "PRES" -> Just PRES_
    "END" -> Just END_
    "OK" -> Just OK_
    "ERR" -> Just ERR_
@@ -829,7 +939,7 @@ type family UserProtocol (p :: ProtocolType) :: Constraint where
  UserProtocol PSMP = ()
  UserProtocol PXFTP = ()
  UserProtocol a =
-    (Int ~ Bool, TypeError (Text "Servers for protocol " :<>: ShowType a :<>: Text " cannot be configured by the users"))
+    (Int ~ Bool, TypeError (TE.Text "Servers for protocol " :<>: ShowType a :<>: TE.Text " cannot be configured by the users"))

 userProtocol :: SProtocolType p -> Maybe (Dict (UserProtocol p))
 userProtocol = \case
@@ -1038,6 +1148,8 @@ data ErrorType
    SESSION
  | -- | SMP command is unknown or has invalid syntax
    CMD {cmdErr :: CommandError}
+  | -- | error from proxied relay
+    PROXY {proxyErr :: ProxyError}
  | -- | command authorization error - bad signature or non-existing SMP queue
    AUTH
  | -- | SMP queue capacity is exceeded on the server
@@ -1046,6 +1158,8 @@ data ErrorType
    NO_MSG
  | -- | sent message is too large (> maxMessageLength = 16088 bytes)
    LARGE_MSG
+  | -- | relay public key is expired
+    EXPIRED
  | -- | internal server error
    INTERNAL
  | -- | used internally, never returned by the server (to be removed)
@@ -1055,8 +1169,12 @@ data ErrorType
 instance StrEncoding ErrorType where
  strEncode = \case
    CMD e -> "CMD " <> bshow e
+    PROXY e -> "PROXY " <> strEncode e
    e -> bshow e
-  strP = "CMD " *> (CMD <$> parseRead1) <|> parseRead1
+  strP =
+    "CMD " *> (CMD <$> parseRead1)
+      <|> "PROXY " *> (PROXY <$> strP)
+      <|> parseRead1

 -- | SMP command error type.
 data CommandError
@@ -1074,6 +1192,21 @@ data CommandError
    NO_ENTITY
  deriving (Eq, Read, Show)

+data ProxyError
+  = -- | Correctly parsed SMP server ERR response.
+    -- This error is forwarded to the agent client as `ERR SMP err`.
+    PROTOCOL {protocolErr :: ErrorType}
+  | -- | Invalid server response that failed to parse.
+    -- Forwarded to the agent client as `ERR BROKER RESPONSE`.
+    RESPONSE {responseErr :: ErrorType}
+  | UNEXPECTED {unexpectedResponse :: String} -- 'String' for using derived JSON and Arbitrary instances
+  | TIMEOUT
+  | NETWORK
+  | BAD_HOST
+  | NO_SESSION
+  | TRANSPORT {transportErr :: TransportError}
+  deriving (Eq, Read, Show)
+
 -- | SMP transmission parser.
 transmissionP :: THandleParams v p -> Parser RawTransmission
 transmissionP THandleParams {sessionId, implySessId} = do
@@ -1135,6 +1268,9 @@ instance PartyI p => ProtocolEncoding SMPVersion ErrorType (Command p) where
    SEND flags msg -> e (SEND_, ' ', flags, ' ', Tail msg)
    PING -> e PING_
    NSUB -> e NSUB_
+    PRXY host auth_ -> e (PRXY_, ' ', host, auth_)
+    PFWD pubKey (EncTransmission s) -> e (PFWD_, ' ', pubKey, Tail s)
+    RFWD (EncFwdTransmission s) -> e (RFWD_, ' ', Tail s)
    where
      e :: Encoding a => a -> ByteString
      e = smpEncode
@@ -1144,24 +1280,33 @@ instance PartyI p => ProtocolEncoding SMPVersion ErrorType (Command p) where
  fromProtocolError = fromProtocolError @SMPVersion @ErrorType @BrokerMsg
  {-# INLINE fromProtocolError #-}

-  checkCredentials (auth, _, queueId, _) cmd = case cmd of
+  checkCredentials (auth, _, entId, _) cmd = case cmd of
    -- NEW must have signature but NOT queue ID
    NEW {}
      | isNothing auth -> Left $ CMD NO_AUTH
-      | not (B.null queueId) -> Left $ CMD HAS_AUTH
+      | not (B.null entId) -> Left $ CMD HAS_AUTH
      | otherwise -> Right cmd
    -- SEND must have queue ID, signature is not always required
    SEND {}
-      | B.null queueId -> Left $ CMD NO_ENTITY
+      | B.null entId -> Left $ CMD NO_ENTITY
      | otherwise -> Right cmd
-    -- PING must not have queue ID or signature
-    PING
-      | isNothing auth && B.null queueId -> Right cmd
+    PING -> noAuthCmd
+    PRXY {} -> noAuthCmd
+    PFWD {}
+      | B.null entId -> Left $ CMD NO_ENTITY
+      | isNothing auth -> Right cmd
      | otherwise -> Left $ CMD HAS_AUTH
+    RFWD _ -> noAuthCmd
    -- other client commands must have both signature and queue ID
    _
-      | isNothing auth || B.null queueId -> Left $ CMD NO_AUTH
+      | isNothing auth || B.null entId -> Left $ CMD NO_AUTH
      | otherwise -> Right cmd
+    where
+      -- command must not have entity ID (queue or session ID) or signature
+      noAuthCmd :: Either ErrorType (Command p)
+      noAuthCmd
+        | isNothing auth && B.null entId = Right cmd
+        | otherwise = Left $ CMD HAS_AUTH

 instance ProtocolEncoding SMPVersion ErrorType Cmd where
  type Tag Cmd = CmdTag
@@ -1189,6 +1334,11 @@ instance ProtocolEncoding SMPVersion ErrorType Cmd where
      Cmd SSender <$> case tag of
        SEND_ -> SEND <$> _smpP <*> (unTail <$> _smpP)
        PING_ -> pure PING
+        RFWD_ -> RFWD <$> (EncFwdTransmission . unTail <$> _smpP)
+    CT SProxiedClient tag ->
+      Cmd SProxiedClient <$> case tag of
+        PFWD_ -> PFWD <$> _smpP <*> (EncTransmission . unTail <$> smpP)
+        PRXY_ -> PRXY <$> _smpP <*> smpP
    CT SNotifier NSUB_ -> pure $ Cmd SNotifier NSUB

  fromProtocolError = fromProtocolError @SMPVersion @ErrorType @BrokerMsg
@@ -1204,6 +1354,9 @@ instance ProtocolEncoding SMPVersion ErrorType BrokerMsg where
      e (MSG_, ' ', msgId, Tail body)
    NID nId srvNtfDh -> e (NID_, ' ', nId, srvNtfDh)
    NMSG nmsgNonce encNMsgMeta -> e (NMSG_, ' ', nmsgNonce, encNMsgMeta)
+    PKEY sid vr (cert, key) -> e (PKEY_, ' ', sid, vr, C.encodeCertChain cert, C.SignedObject key)
+    RRES (EncFwdResponse encBlock) -> e (RRES_, ' ', Tail encBlock)
+    PRES (EncResponse encBlock) -> e (PRES_, ' ', Tail encBlock)
    END -> e END_
    OK -> e OK_
    ERR err -> e (ERR_, ' ', err)
@@ -1221,6 +1374,9 @@ instance ProtocolEncoding SMPVersion ErrorType BrokerMsg where
    IDS_ -> IDS <$> (QIK <$> _smpP <*> smpP <*> smpP)
    NID_ -> NID <$> _smpP <*> smpP
    NMSG_ -> NMSG <$> _smpP <*> smpP
+    PKEY_ -> PKEY <$> _smpP <*> smpP <*> ((,) <$> C.certChainP <*> (C.getSignedExact <$> smpP))
+    RRES_ -> RRES <$> (EncFwdResponse . unTail <$> _smpP)
+    PRES_ -> PRES <$> (EncResponse . unTail <$> _smpP)
    END_ -> pure END
    OK_ -> pure OK
    ERR_ -> ERR <$> _smpP
@@ -1233,19 +1389,24 @@ instance ProtocolEncoding SMPVersion ErrorType BrokerMsg where
    PEBlock -> BLOCK
  {-# INLINE fromProtocolError #-}

-  checkCredentials (_, _, queueId, _) cmd = case cmd of
+  checkCredentials (_, _, entId, _) cmd = case cmd of
    -- IDS response should not have queue ID
    IDS _ -> Right cmd
    -- ERR response does not always have queue ID
    ERR _ -> Right cmd
    -- PONG response must not have queue ID
-    PONG
-      | B.null queueId -> Right cmd
-      | otherwise -> Left $ CMD HAS_AUTH
+    PONG -> noEntityMsg
+    PKEY {} -> noEntityMsg
+    RRES _ -> noEntityMsg
    -- other broker responses must have queue ID
    _
-      | B.null queueId -> Left $ CMD NO_ENTITY
+      | B.null entId -> Left $ CMD NO_ENTITY
      | otherwise -> Right cmd
+    where
+      noEntityMsg :: Either ErrorType BrokerMsg
+      noEntityMsg
+        | B.null entId = Right cmd
+        | otherwise = Left $ CMD HAS_AUTH

 -- | Parse SMP protocol commands and broker messages
 parseProtocol :: forall v err msg. ProtocolEncoding v err msg => Version v -> ByteString -> Either err msg
@@ -1268,8 +1429,10 @@ instance Encoding ErrorType where
    BLOCK -> "BLOCK"
    SESSION -> "SESSION"
    CMD err -> "CMD " <> smpEncode err
+    PROXY err -> "PROXY " <> smpEncode err
    AUTH -> "AUTH"
    QUOTA -> "QUOTA"
+    EXPIRED -> "EXPIRED"
    NO_MSG -> "NO_MSG"
    LARGE_MSG -> "LARGE_MSG"
    INTERNAL -> "INTERNAL"
@@ -1280,8 +1443,10 @@ instance Encoding ErrorType where
      "BLOCK" -> pure BLOCK
      "SESSION" -> pure SESSION
      "CMD" -> CMD <$> _smpP
+      "PROXY" -> PROXY <$> _smpP
      "AUTH" -> pure AUTH
      "QUOTA" -> pure QUOTA
+      "EXPIRED" -> pure EXPIRED
      "NO_MSG" -> pure NO_MSG
      "LARGE_MSG" -> pure LARGE_MSG
      "INTERNAL" -> pure INTERNAL
@@ -1304,9 +1469,47 @@ instance Encoding CommandError where
      "NO_AUTH" -> pure NO_AUTH
      "HAS_AUTH" -> pure HAS_AUTH
      "NO_ENTITY" -> pure NO_ENTITY
-      "NO_QUEUE" -> pure NO_ENTITY
+      "NO_QUEUE" -> pure NO_ENTITY -- for backward compatibility
      _ -> fail "bad command error type"

+instance Encoding ProxyError where
+  smpEncode e = case e of
+    PROTOCOL et -> "PROTOCOL " <> smpEncode et
+    RESPONSE et -> "RESPONSE " <> smpEncode et
+    UNEXPECTED s -> "UNEXPECTED " <> smpEncode (encodeUtf8 $ T.pack s)
+    TIMEOUT -> "TIMEOUT"
+    NETWORK -> "NETWORK"
+    BAD_HOST -> "BAD_HOST"
+    NO_SESSION -> "NO_SESSION"
+    TRANSPORT t -> "TRANSPORT " <> serializeTransportError t
+  smpP =
+    A.takeTill (== ' ') >>= \case
+      "PROTOCOL" -> PROTOCOL <$> _smpP
+      "RESPONSE" -> RESPONSE <$> _smpP
+      "UNEXPECTED" -> UNEXPECTED . (T.unpack . safeDecodeUtf8) <$> _smpP
+      "TIMEOUT" -> pure TIMEOUT
+      "NETWORK" -> pure NETWORK
+      "BAD_HOST" -> pure BAD_HOST
+      "NO_SESSION" -> pure NO_SESSION
+      "TRANSPORT" -> TRANSPORT <$> (A.space *> transportErrorP)
+      _ -> fail "bad command error type"
+
+instance StrEncoding ProxyError where
+  strEncode = \case
+    PROTOCOL et -> "PROTOCOL " <> strEncode et
+    RESPONSE et -> "RESPONSE " <> strEncode et
+    UNEXPECTED "" -> "UNEXPECTED" -- Arbitrary instance generates empty strings which String instance can't handle
+    UNEXPECTED s -> "UNEXPECTED " <> strEncode s
+    TRANSPORT t -> "TRANSPORT " <> serializeTransportError t
+    e -> bshow e
+  strP =
+    "PROTOCOL " *> (PROTOCOL <$> strP)
+      <|> "RESPONSE " *> (RESPONSE <$> strP)
+      <|> "UNEXPECTED " *> (UNEXPECTED <$> strP)
+      <|> "UNEXPECTED" $> UNEXPECTED ""
+      <|> "TRANSPORT " *> (TRANSPORT <$> transportErrorP)
+      <|> parseRead1
+
 -- | Send signed SMP transmission to TCP transport.
 tPut :: Transport c => THandle v c p -> NonEmpty (Either TransportError SentRawTransmission) -> IO [Either TransportError ()]
 tPut th@THandle {params} = fmap concat . mapM tPutBatch . batchTransmissions (batch params) (blockSize params)
@@ -1444,4 +1647,5 @@ $(J.deriveJSON defaultJSON ''MsgFlags)

 $(J.deriveJSON (sumTypeJSON id) ''CommandError)

-$(J.deriveJSON (sumTypeJSON id) ''ErrorType)
+-- run deriveJSON in one TH splice to allow mutual instance
+$(concat <$> mapM @[] (J.deriveJSON (sumTypeJSON id)) [''ProxyError, ''ErrorType])
@@ -13,7 +13,6 @@
 {-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TupleSections #-}
-{-# LANGUAGE TypeApplications #-}

 -- |
 -- Module      : Simplex.Messaging.Server
@@ -43,6 +42,7 @@ import Control.Monad
 import Control.Monad.Except
 import Control.Monad.IO.Unlift
 import Control.Monad.Reader
+import Control.Monad.Trans.Except
 import Crypto.Random
 import Data.Bifunctor (first)
 import Data.ByteString.Base64 (encode)
@@ -53,7 +53,7 @@ import Data.Either (fromRight, partitionEithers)
 import Data.Functor (($>))
 import Data.Int (Int64)
 import qualified Data.IntMap.Strict as IM
-import Data.List (intercalate, mapAccumR)
+import Data.List (intercalate)
 import Data.List.NonEmpty (NonEmpty)
 import qualified Data.List.NonEmpty as L
 import qualified Data.Map.Strict as M
@@ -68,8 +68,10 @@ import GHC.Stats (getRTSStats)
 import GHC.TypeLits (KnownNat)
 import Network.Socket (ServiceName, Socket, socketToHandle)
 import Simplex.Messaging.Agent.Lock
+import Simplex.Messaging.Client (ProtocolClient (thParams), ProtocolClientError (PCEIOError), forwardSMPMessage, smpProxyError)
+import Simplex.Messaging.Client.Agent (SMPClientAgent (..), SMPClientAgentEvent (..), getSMPServerClient', lookupSMPServerClient)
 import qualified Simplex.Messaging.Crypto as C
-import Simplex.Messaging.Encoding (Encoding (smpEncode))
+import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol
 import Simplex.Messaging.Server.Control
@@ -91,6 +93,7 @@ import System.Exit (exitFailure)
 import System.IO (hPrint, hPutStrLn, hSetNewlineMode, universalNewlineMode)
 import System.Mem.Weak (deRefWeak)
 import UnliftIO (timeout)
+import UnliftIO.Async (mapConcurrently)
 import UnliftIO.Concurrent
 import UnliftIO.Directory (doesFileExist, renameFile)
 import UnliftIO.Exception
@@ -123,11 +126,13 @@ type M a = ReaderT Env IO a
 smpServer :: TMVar Bool -> ServerConfig -> M ()
 smpServer started cfg@ServerConfig {transports, transportConfig = tCfg} = do
  s <- asks server
+  pa <- asks proxyAgent
  expired <- restoreServerMessages
  restoreServerStats expired
  raceAny_
    ( serverThread s "server subscribedQ" subscribedQ subscribers subscriptions cancelSub
        : serverThread s "server ntfSubscribedQ" ntfSubscribedQ Env.notifiers ntfSubscriptions (\_ -> pure ())
+        : receiveFromProxyAgent pa
        : map runServer transports <> expireMessagesThread_ cfg <> serverStatsThread_ cfg <> controlPortThread_ cfg
    )
    `finally` withLock' (savingLock s) "final" (saveServer False)
@@ -180,6 +185,19 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg} = do
          mkWeakThreadId t >>= atomically . modifyTVar' (endThreads c) . IM.insert tId
          atomically $ TM.lookupDelete qId (clientSubs c)

+    receiveFromProxyAgent :: ProxyAgent -> M ()
+    receiveFromProxyAgent ProxyAgent {smpAgent = SMPClientAgent {agentQ}} =
+      forever $
+        atomically (readTBQueue agentQ) >>= \case
+          CAConnected srv -> logInfo $ "SMP server connected " <> showServer' srv
+          CADisconnected srv [] -> logInfo $ "SMP server disconnected " <> showServer' srv
+          CADisconnected srv subs -> logError $ "SMP server disconnected " <> showServer' srv <> " / subscriptions: " <> tshow (length subs)
+          CAReconnected srv -> logInfo $ "SMP server reconnected " <> showServer' srv
+          CAResubscribed srv subs -> logError $ "SMP server resubscribed " <> showServer' srv <> " / subscriptions: " <> tshow (length subs)
+          CASubError srv errs -> logError $ "SMP server subscription errors " <> showServer' srv <> " / errors: " <> tshow (length errs)
+      where
+        showServer' = decodeLatin1 . strEncode . host
+
    expireMessagesThread_ :: ServerConfig -> [M ()]
    expireMessagesThread_ ServerConfig {messageExpiration = Just msgExp} = [expireMessages msgExp]
    expireMessagesThread_ _ = []
@@ -315,7 +333,7 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg} = do
              CPResume -> withAdminRole $ hPutStrLn h "resume not implemented"
              CPClients -> withAdminRole $ do
                active <- unliftIO u (asks clients) >>= readTVarIO
-                hPutStrLn h $ "clientId,sessionId,connected,createdAt,rcvActiveAt,sndActiveAt,age,subscriptions"
+                hPutStrLn h "clientId,sessionId,connected,createdAt,rcvActiveAt,sndActiveAt,age,subscriptions"
                forM_ (IM.toList active) $ \(cid, Client {sessionId, connected, createdAt, rcvActiveAt, sndActiveAt, subscriptions}) -> do
                  connected' <- bshow <$> readTVarIO connected
                  rcvActiveAt' <- strEncode <$> readTVarIO rcvActiveAt
@@ -411,7 +429,7 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg} = do
                    hPutStrLn h "AUTH"

 runClientTransport :: Transport c => THandleSMP c 'TServer -> M ()
-runClientTransport h@THandle {params = THandleParams {thVersion, sessionId}} = do
+runClientTransport th@THandle {params = thParams@THandleParams {thVersion, sessionId}} = do
  q <- asks $ tbqSize . config
  ts <- liftIO getSystemTime
  active <- asks clients
@@ -422,12 +440,11 @@ runClientTransport h@THandle {params = THandleParams {thVersion, sessionId}} = d
    pure new
  s <- asks server
  expCfg <- asks $ inactiveClientExpiration . config
-  th <- newMVar h -- put TH under a fair lock to interleave messages and command responses
  labelMyThread . B.unpack $ "client $" <> encode sessionId
-  raceAny_ ([liftIO $ send th c, liftIO $ sendMsg th c, client c s, receive h c] <> disconnectThread_ c expCfg)
+  raceAny_ ([liftIO $ send th c, client thParams c s, receive th c] <> disconnectThread_ c expCfg)
    `finally` clientDisconnected c
  where
-    disconnectThread_ c (Just expCfg) = [liftIO $ disconnectTransport h (rcvActiveAt c) (sndActiveAt c) expCfg (noSubscriptions c)]
+    disconnectThread_ c (Just expCfg) = [liftIO $ disconnectTransport th (rcvActiveAt c) (sndActiveAt c) expCfg (noSubscriptions c)]
    disconnectThread_ _ _ = []
    noSubscriptions c = atomically $ (&&) <$> TM.null (subscriptions c) <*> TM.null (ntfSubscriptions c)

@@ -460,61 +477,40 @@ cancelSub sub =
    _ -> return ()

 receive :: Transport c => THandleSMP c 'TServer -> Client -> M ()
-receive h@THandle {params = THandleParams {thAuth}} Client {rcvQ, sndQ, rcvActiveAt, sessionId} = do
+receive th@THandle {params = THandleParams {thAuth}} Client {rcvQ, sndQ, rcvActiveAt, sessionId} = do
  labelMyThread . B.unpack $ "client $" <> encode sessionId <> " receive"
  forever $ do
-    ts <- L.toList <$> liftIO (tGet h)
+    ts <- L.toList <$> liftIO (tGet th)
    atomically . writeTVar rcvActiveAt =<< liftIO getSystemTime
-    as <- partitionEithers <$> mapM cmdAction ts
-    write sndQ $ fst as
-    write rcvQ $ snd as
+    (errs, cmds) <- partitionEithers <$> mapM cmdAction ts
+    write sndQ errs
+    write rcvQ cmds
  where
    cmdAction :: SignedTransmission ErrorType Cmd -> M (Either (Transmission BrokerMsg) (Maybe QueueRec, Transmission Cmd))
-    cmdAction (tAuth, authorized, (corrId, queueId, cmdOrError)) =
+    cmdAction (tAuth, authorized, (corrId, entId, cmdOrError)) =
      case cmdOrError of
-        Left e -> pure $ Left (corrId, queueId, ERR e)
-        Right cmd -> verified <$> verifyTransmission ((,C.cbNonce (bs corrId)) <$> thAuth) tAuth authorized queueId cmd
+        Left e -> pure $ Left (corrId, entId, ERR e)
+        Right cmd -> verified <$> verifyTransmission ((,C.cbNonce (bs corrId)) <$> thAuth) tAuth authorized entId cmd
          where
            verified = \case
-              VRVerified qr -> Right (qr, (corrId, queueId, cmd))
-              VRFailed -> Left (corrId, queueId, ERR AUTH)
+              VRVerified qr -> Right (qr, (corrId, entId, cmd))
+              VRFailed -> Left (corrId, entId, ERR AUTH)
    write q = mapM_ (atomically . writeTBQueue q) . L.nonEmpty

-send :: Transport c => MVar (THandleSMP c 'TServer) -> Client -> IO ()
-send th c@Client {sndQ, msgQ, sessionId} = do
+send :: Transport c => THandleSMP c 'TServer -> Client -> IO ()
+send h@THandle {params} Client {sndQ, sessionId, sndActiveAt} = do
  labelMyThread . B.unpack $ "client $" <> encode sessionId <> " send"
-  forever $ atomically (readTBQueue sndQ) >>= sendTransmissions
+  forever $ do
+    ts <- atomically $ L.sortWith tOrder <$> readTBQueue sndQ
+    -- TODO we can authorize responses as well
+    void . liftIO . tPut h $ L.map (\t -> Right (Nothing, encodeTransmission params t)) ts
+    atomically . writeTVar sndActiveAt =<< liftIO getSystemTime
  where
-    sendTransmissions :: NonEmpty (Transmission BrokerMsg) -> IO ()
-    sendTransmissions ts
-      | L.length ts <= 2 = tSend th c ts
-      | otherwise = do
-          let (msgs_, ts') = mapAccumR splitMessages [] ts
-          -- If the request had batched subscriptions (L.length ts > 2)
-          -- this will reply OK to all SUBs in the first batched transmission,
-          -- to reduce client timeouts.
-          tSend th c ts'
-          -- After that all messages will be sent in separate transmissions,
-          -- without any client response timeouts, and allowing them to interleave
-          -- with other requests responses.
-          mapM_ (atomically . writeTBQueue msgQ) $ L.nonEmpty msgs_
-      where
-        splitMessages :: [Transmission BrokerMsg] -> Transmission BrokerMsg -> ([Transmission BrokerMsg], Transmission BrokerMsg)
-        splitMessages msgs t@(corrId, entId, cmd) = case cmd of
-          -- replace MSG response with OK, accumulating MSG in a separate list.
-          MSG {} -> ((CorrId "", entId, cmd) : msgs, (corrId, entId, OK))
-          _ -> (msgs, t)
-
-sendMsg :: Transport c => MVar (THandleSMP c 'TServer) -> Client -> IO ()
-sendMsg th c@Client {msgQ, sessionId} = do
-  labelMyThread . B.unpack $ "client $" <> encode sessionId <> " sendMsg"
-  forever $ atomically (readTBQueue msgQ) >>= mapM_ (\t -> tSend th c [t])
-
-tSend :: Transport c => MVar (THandleSMP c 'TServer) -> Client -> NonEmpty (Transmission BrokerMsg) -> IO ()
-tSend th Client {sndActiveAt} ts = do
-  withMVar th $ \h@THandle {params} ->
-    void . tPut h $ L.map (\t -> Right (Nothing, encodeTransmission params t)) ts
-  atomically . writeTVar sndActiveAt =<< liftIO getSystemTime
+    tOrder :: Transmission BrokerMsg -> Int
+    tOrder (_, _, cmd) = case cmd of
+      MSG {} -> 0
+      NMSG {} -> 0
+      _ -> 1

 disconnectTransport :: Transport c => THandle v c 'TServer -> TVar SystemTime -> TVar SystemTime -> ExpirationConfig -> IO Bool -> IO ()
 disconnectTransport THandle {connection, params = THandleParams {sessionId}} rcvActiveAt sndActiveAt expCfg noSubscriptions = do
@@ -545,16 +541,18 @@ verifyTransmission auth_ tAuth authorized queueId cmd =
    -- SEND will be accepted without authorization before the queue is secured with KEY command
    Cmd SSender SEND {} -> verifyQueue (\q -> Just q `verified` maybe (isNothing tAuth) verify (senderKey q)) <$> get SSender
    Cmd SSender PING -> pure $ VRVerified Nothing
+    Cmd SSender RFWD {} -> pure $ VRVerified Nothing
    -- NSUB will not be accepted without authorization
-    Cmd SNotifier NSUB -> verifyQueue (\q -> maybe dummyVerify (Just q `verifiedWith`) (notifierKey <$> notifier q)) <$> get SNotifier
+    Cmd SNotifier NSUB -> verifyQueue (\q -> maybe dummyVerify (\n -> Just q `verifiedWith` notifierKey n) (notifier q)) <$> get SNotifier
+    Cmd SProxiedClient _ -> pure $ VRVerified Nothing
  where
    verify = verifyCmdAuthorization auth_ tAuth authorized
    dummyVerify = verify (dummyAuthKey tAuth) `seq` VRFailed
    verifyQueue :: (QueueRec -> VerificationResult) -> Either ErrorType QueueRec -> VerificationResult
-    verifyQueue = either (\_ -> dummyVerify)
+    verifyQueue = either (const dummyVerify)
    verified q cond = if cond then VRVerified q else VRFailed
    verifiedWith q k = q `verified` verify k
-    get :: SParty p -> M (Either ErrorType QueueRec)
+    get :: DirectParty p => SParty p -> M (Either ErrorType QueueRec)
    get party = do
      st <- asks queueStore
      atomically $ getQueue st party queueId
@@ -604,25 +602,54 @@ dummyKeyEd448 = "MEMwBQYDK2VxAzoA6ibQc9XpkSLtwrf7PLvp81qW/etiumckVFImCMRdftcG/Xo
 dummyKeyX25519 :: C.PublicKey 'C.X25519
 dummyKeyX25519 = "MCowBQYDK2VuAyEA4JGSMYht18H4mas/jHeBwfcM7jLwNYJNOAhi2/g4RXg="

-client :: Client -> Server -> M ()
-client clnt@Client {subscriptions, ntfSubscriptions, rcvQ, sndQ, sessionId} Server {subscribedQ, ntfSubscribedQ, notifiers} = do
+client :: THandleParams SMPVersion 'TServer -> Client -> Server -> M ()
+client thParams' clnt@Client {subscriptions, ntfSubscriptions, rcvQ, sndQ, sessionId} Server {subscribedQ, ntfSubscribedQ, notifiers} = do
  labelMyThread . B.unpack $ "client $" <> encode sessionId <> " commands"
-  forever $
-    atomically (readTBQueue rcvQ)
-      >>= mapM processCommand
-      >>= atomically . writeTBQueue sndQ
+  forever $ do
+    (proxied, rs) <- partitionEithers . L.toList <$> (mapM processCommand =<< atomically (readTBQueue rcvQ))
+    forM_ (L.nonEmpty rs) reply
+    -- TODO cancel this thread if the client gets disconnected
+    -- TODO limit client concurrency
+    forM_ (L.nonEmpty proxied) $ \cmds -> forkIO $ mapConcurrently processProxiedCmd cmds >>= reply
  where
-    processCommand :: (Maybe QueueRec, Transmission Cmd) -> M (Transmission BrokerMsg)
+    reply :: MonadIO m => NonEmpty (Transmission BrokerMsg) -> m ()
+    reply = atomically . writeTBQueue sndQ
+    processProxiedCmd :: Transmission (Command 'ProxiedClient) -> M (Transmission BrokerMsg)
+    processProxiedCmd (corrId, sessId, command) = (corrId, sessId,) <$> case command of
+      PRXY srv auth -> ifM allowProxy getRelay (pure $ ERR AUTH)
+        where
+          allowProxy = do
+            ServerConfig {allowSMPProxy, newQueueBasicAuth} <- asks config
+            pure $ allowSMPProxy && maybe True ((== auth) . Just) newQueueBasicAuth
+          getRelay = do
+            ProxyAgent {smpAgent} <- asks proxyAgent
+            liftIO $ proxyResp <$> runExceptT (getSMPServerClient' smpAgent srv) `catch` (pure . Left . PCEIOError)
+            where
+              proxyResp = \case
+                Right smp ->
+                  let THandleParams {sessionId = srvSessId, thAuth} = thParams smp
+                      vr = supportedServerSMPRelayVRange
+                   in case thAuth of
+                        Just THAuthClient {serverCertKey} -> PKEY srvSessId vr serverCertKey
+                        Nothing -> ERR $ PROXY (TRANSPORT TENoServerAuth)
+                Left err -> ERR $ smpProxyError err
+      PFWD pubKey encBlock -> do
+        ProxyAgent {smpAgent} <- asks proxyAgent
+        atomically (lookupSMPServerClient smpAgent sessId) >>= \case
+          Just smp -> liftIO $ either (ERR . smpProxyError) PRES <$> runExceptT (forwardSMPMessage smp corrId pubKey encBlock)
+          Nothing -> pure $ ERR $ PROXY NO_SESSION
+    processCommand :: (Maybe QueueRec, Transmission Cmd) -> M (Either (Transmission (Command 'ProxiedClient)) (Transmission BrokerMsg))
    processCommand (qr_, (corrId, queueId, cmd)) = do
      st <- asks queueStore
      case cmd of
-        Cmd SSender command ->
-          case command of
-            SEND flags msgBody -> withQueue $ \qr -> sendMessage qr flags msgBody
-            PING -> pure (corrId, "", PONG)
-        Cmd SNotifier NSUB -> subscribeNotifications
+        Cmd SProxiedClient command -> pure $ Left (corrId, queueId, command)
+        Cmd SSender command -> Right <$> case command of
+          SEND flags msgBody -> withQueue $ \qr -> sendMessage qr flags msgBody
+          PING -> pure (corrId, "", PONG)
+          RFWD encBlock -> (corrId, "",) <$> processForwardedCommand encBlock
+        Cmd SNotifier NSUB -> Right <$> subscribeNotifications
        Cmd SRecipient command ->
-          case command of
+          Right <$> case command of
            NEW rKey dhKey auth subMode ->
              ifM
                allowNew
@@ -886,6 +913,58 @@ client clnt@Client {subscriptions, ntfSubscriptions, rcvQ, sndQ, sessionId} Serv
                  encNMsgMeta = C.cbEncrypt rcvNtfDhSecret cbNonce (smpEncode msgMeta) 128
              pure . (cbNonce,) $ fromRight "" encNMsgMeta

+        processForwardedCommand :: EncFwdTransmission -> M BrokerMsg
+        processForwardedCommand (EncFwdTransmission s) = fmap (either id id) . runExceptT $ do
+          -- TODO error
+          THAuthServer {serverPrivKey, sessSecret'} <- maybe (throwError $ ERR INTERNAL) pure thAuth
+          sessSecret <- maybe (throwError $ ERR INTERNAL) pure sessSecret'
+          let proxyNonce = C.cbNonce $ bs corrId
+          -- TODO error
+          s' <- liftEitherWith internalErr $ C.cbDecrypt sessSecret proxyNonce s
+          -- TODO error
+          FwdTransmission {fwdCorrId, fwdKey, fwdTransmission = EncTransmission et} <- liftEitherWith internalErr $ smpDecode s'
+          -- TODO error - this error is reported to proxy, as we failed to get to client's transmission
+          let clientSecret = C.dh' fwdKey serverPrivKey
+              clientNonce = C.cbNonce $ bs fwdCorrId
+          b <- liftEitherWith internalErr $ C.cbDecrypt clientSecret clientNonce et
+          -- only allowing single forwarded transactions
+          let t' = tDecodeParseValidate thParams' $ L.head $ tParse thParams' b
+              clntThAuth = Just $ THAuthServer {serverPrivKey, sessSecret' = Just clientSecret}
+          -- TODO error
+          r <-
+            lift (rejectOrVerify clntThAuth t') >>= \case
+              Left r -> pure r
+              Right t''@(_, (corrId', entId', _)) ->
+                -- Left will not be returned by processCommand, as only SEND command is allowed
+                fromRight (corrId', entId', ERR INTERNAL) <$> lift (processCommand t'')
+
+          -- encode response
+          r' <- case batchTransmissions (batch thParams') (blockSize thParams') [Right (Nothing, encodeTransmission thParams' r)] of
+            [] -> throwE $ ERR INTERNAL -- TODO error
+            TBError _ _ : _ -> throwE $ ERR INTERNAL -- TODO error
+            TBTransmission b' _ : _ -> pure b'
+            TBTransmissions b' _ _ : _ -> pure b'
+          -- encrypt to client
+          r2 <- liftEitherWith internalErr $ EncResponse <$> C.cbEncrypt clientSecret (C.reverseNonce clientNonce) r' paddedProxiedMsgLength
+          -- encrypt to proxy
+          let fr = FwdResponse {fwdCorrId, fwdResponse = r2}
+          r3 <- liftEitherWith internalErr $ EncFwdResponse <$> C.cbEncrypt sessSecret (C.reverseNonce proxyNonce) (smpEncode fr) paddedForwardedMsgLength
+          pure $ RRES r3
+          where
+            internalErr _ = ERR INTERNAL -- TODO errors
+            THandleParams {thAuth} = thParams'
+            rejectOrVerify :: Maybe (THandleAuth 'TServer) -> SignedTransmission ErrorType Cmd -> M (Either (Transmission BrokerMsg) (Maybe QueueRec, Transmission Cmd))
+            rejectOrVerify clntThAuth (tAuth, authorized, (corrId', entId', cmdOrError)) =
+              case cmdOrError of
+                Left e -> pure $ Left (corrId', entId', ERR e)
+                -- flags msgBody -> withQueue $ \qr -> sendMessage qr flags msgBody
+                Right cmd'@(Cmd SSender SEND {}) -> verified <$> verifyTransmission ((,C.cbNonce (bs corrId')) <$> clntThAuth) tAuth authorized entId' cmd'
+                  where
+                    verified = \case
+                      VRVerified qr -> Right (qr, (corrId', entId', cmd'))
+                      VRFailed -> Left (corrId', entId', ERR AUTH)
+                Right _ -> pure $ Left (corrId', entId', ERR $ CMD PROHIBITED)
+
        deliverMessage :: T.Text -> QueueRec -> RecipientId -> TVar Sub -> MsgQueue -> Maybe Message -> M (Transmission BrokerMsg)
        deliverMessage name qr rId sub q msg_ = time (name <> " deliver") $ do
          readTVarIO sub >>= \case
@@ -998,10 +1077,9 @@ saveServerMessages keepMsgs = asks (storeMsgsFile . config) >>= mapM_ saveMessag
            >>= mapM_ (B.hPutStrLn h . strEncode . MLRv3 rId)

 restoreServerMessages :: M Int
-restoreServerMessages =
-  asks (storeMsgsFile . config) >>= \case
-    Just f -> ifM (doesFileExist f) (restoreMessages f) (pure 0)
-    Nothing -> pure 0
+restoreServerMessages = asks (storeMsgsFile . config) >>= \case
+  Just f -> ifM (doesFileExist f) (restoreMessages f) (pure 0)
+  Nothing -> pure 0
  where
    restoreMessages f = do
      logInfo $ "restoring messages from file " <> T.pack f
@@ -22,6 +22,7 @@ import Network.Socket (ServiceName)
 import qualified Network.TLS as T
 import Numeric.Natural
 import Simplex.Messaging.Agent.Lock
+import Simplex.Messaging.Client.Agent (SMPClientAgent, SMPClientAgentConfig, newSMPClientAgent)
 import Simplex.Messaging.Crypto (KeyHash (..))
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Protocol
@@ -34,7 +35,7 @@ import Simplex.Messaging.Server.StoreLog
 import Simplex.Messaging.TMap (TMap)
 import qualified Simplex.Messaging.TMap as TM
 import Simplex.Messaging.Transport (ATransport, VersionRangeSMP, VersionSMP)
-import Simplex.Messaging.Transport.Server (SocketState, TransportServerConfig, alpn, loadFingerprint, loadTLSServerParams, newSocketState)
+import Simplex.Messaging.Transport.Server (SocketState, TransportServerConfig, loadFingerprint, loadTLSServerParams, newSocketState)
 import System.IO (IOMode (..))
 import System.Mem.Weak (Weak)
 import UnliftIO.STM
@@ -79,7 +80,9 @@ data ServerConfig = ServerConfig
    -- | TCP transport config
    transportConfig :: TransportServerConfig,
    -- | run listener on control port
-    controlPort :: Maybe ServiceName
+    controlPort :: Maybe ServiceName,
+    smpAgentCfg :: SMPClientAgentConfig,
+    allowSMPProxy :: Bool -- auth is the same with `newQueueBasicAuth`
  }

 defMsgExpirationDays :: Int64
@@ -110,8 +113,9 @@ data Env = Env
    tlsServerParams :: T.ServerParams,
    serverStats :: ServerStats,
    sockets :: SocketState,
-    clientSeq :: TVar Int,
-    clients :: TVar (IntMap Client)
+    clientSeq :: TVar ClientId,
+    clients :: TVar (IntMap Client),
+    proxyAgent :: ProxyAgent -- senders served on this proxy
  }

 data Server = Server
@@ -122,13 +126,18 @@ data Server = Server
    savingLock :: Lock
  }

+data ProxyAgent = ProxyAgent
+  { smpAgent :: SMPClientAgent
+  }
+
+type ClientId = Int
+
 data Client = Client
-  { clientId :: Int,
+  { clientId :: ClientId,
    subscriptions :: TMap RecipientId (TVar Sub),
    ntfSubscriptions :: TMap NotifierId (),
    rcvQ :: TBQueue (NonEmpty (Maybe QueueRec, Transmission Cmd)),
    sndQ :: TBQueue (NonEmpty (Transmission BrokerMsg)),
-    msgQ :: TBQueue (NonEmpty (Transmission BrokerMsg)),
    endThreads :: TVar (IntMap (Weak ThreadId)),
    endThreadSeq :: TVar Int,
    thVersion :: VersionSMP,
@@ -136,7 +145,8 @@ data Client = Client
    connected :: TVar Bool,
    createdAt :: SystemTime,
    rcvActiveAt :: TVar SystemTime,
-    sndActiveAt :: TVar SystemTime
+    sndActiveAt :: TVar SystemTime,
+    proxyClient_ :: TVar (Maybe C.DhSecretX25519) -- this client is actually an SMP proxy
  }

 data SubscriptionThread = NoSub | SubPending | SubThread (Weak ThreadId) | ProhibitSub
@@ -155,20 +165,20 @@ newServer = do
  savingLock <- createLock
  return Server {subscribedQ, subscribers, ntfSubscribedQ, notifiers, savingLock}

-newClient :: TVar Int -> Natural -> VersionSMP -> ByteString -> SystemTime -> STM Client
+newClient :: TVar ClientId -> Natural -> VersionSMP -> ByteString -> SystemTime -> STM Client
 newClient nextClientId qSize thVersion sessionId createdAt = do
  clientId <- stateTVar nextClientId $ \next -> (next, next + 1)
  subscriptions <- TM.empty
  ntfSubscriptions <- TM.empty
  rcvQ <- newTBQueue qSize
  sndQ <- newTBQueue qSize
-  msgQ <- newTBQueue qSize
  endThreads <- newTVar IM.empty
  endThreadSeq <- newTVar 0
  connected <- newTVar True
  rcvActiveAt <- newTVar createdAt
  sndActiveAt <- newTVar createdAt
-  return Client {clientId, subscriptions, ntfSubscriptions, rcvQ, sndQ, msgQ, endThreads, endThreadSeq, thVersion, sessionId, connected, createdAt, rcvActiveAt, sndActiveAt}
+  proxyClient_ <- newTVar Nothing
+  return Client {clientId, subscriptions, ntfSubscriptions, rcvQ, sndQ, endThreads, endThreadSeq, thVersion, sessionId, connected, createdAt, rcvActiveAt, sndActiveAt, proxyClient_}

 newSubscription :: SubscriptionThread -> STM Sub
 newSubscription subThread = do
@@ -176,20 +186,21 @@ newSubscription subThread = do
  return Sub {subThread, delivered}

 newEnv :: ServerConfig -> IO Env
-newEnv config@ServerConfig {caCertificateFile, certificateFile, privateKeyFile, storeLogFile, transportConfig} = do
+newEnv config@ServerConfig {caCertificateFile, certificateFile, privateKeyFile, storeLogFile, smpAgentCfg} = do
  server <- atomically newServer
  queueStore <- atomically newQueueStore
  msgStore <- atomically newMsgStore
  random <- liftIO C.newRandom
  storeLog <- restoreQueues queueStore `mapM` storeLogFile
-  tlsServerParams <- loadTLSServerParams caCertificateFile certificateFile privateKeyFile (alpn transportConfig)
+  tlsServerParams <- loadTLSServerParams caCertificateFile certificateFile privateKeyFile
  Fingerprint fp <- loadFingerprint caCertificateFile
  let serverIdentity = KeyHash fp
  serverStats <- atomically . newServerStats =<< getCurrentTime
  sockets <- atomically newSocketState
  clientSeq <- newTVarIO 0
  clients <- newTVarIO mempty
-  return Env {config, server, serverIdentity, queueStore, msgStore, random, storeLog, tlsServerParams, serverStats, sockets, clientSeq, clients}
+  proxyAgent <- atomically $ newSMPProxyAgent smpAgentCfg random
+  return Env {config, server, serverIdentity, queueStore, msgStore, random, storeLog, tlsServerParams, serverStats, sockets, clientSeq, clients, proxyAgent}
  where
    restoreQueues :: QueueStore -> FilePath -> IO (StoreLog 'WriteMode)
    restoreQueues QueueStore {queues, senders, notifiers} f = do
@@ -205,3 +216,8 @@ newEnv config@ServerConfig {caCertificateFile, certificateFile, privateKeyFile,
    addNotifier q = case notifier q of
      Nothing -> id
      Just NtfCreds {notifierId} -> M.insert notifierId (recipientId q)
+
+newSMPProxyAgent :: SMPClientAgentConfig -> TVar ChaChaDRG -> STM ProxyAgent
+newSMPProxyAgent smpAgentCfg random = do
+  smpAgent <- newSMPClientAgent smpAgentCfg random
+  pure ProxyAgent {smpAgent}
@@ -18,6 +18,8 @@ import qualified Data.Text as T
 import Data.Text.Encoding (encodeUtf8)
 import Network.Socket (HostName)
 import Options.Applicative
+import Simplex.Messaging.Client (ProtocolClientConfig (..))
+import Simplex.Messaging.Client.Agent (SMPClientAgentConfig (..), defaultSMPClientAgentConfig)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol (BasicAuth (..), ProtoServerWithAuth (ProtoServerWithAuth), pattern SMPServer)
@@ -25,10 +27,11 @@ import Simplex.Messaging.Server (runSMPServer)
 import Simplex.Messaging.Server.CLI
 import Simplex.Messaging.Server.Env.STM (ServerConfig (..), defMsgExpirationDays, defaultInactiveClientExpiration, defaultMessageExpiration)
 import Simplex.Messaging.Server.Expiration
-import Simplex.Messaging.Transport (simplexMQVersion, supportedSMPHandshakes, supportedServerSMPRelayVRange)
+import Simplex.Messaging.Transport (simplexMQVersion, supportedServerSMPRelayVRange, batchCmdsSMPVersion, sendingProxySMPVersion)
 import Simplex.Messaging.Transport.Client (TransportHost (..))
 import Simplex.Messaging.Transport.Server (TransportServerConfig (..), defaultTransportServerConfig)
 import Simplex.Messaging.Util (safeDecodeUtf8)
+import Simplex.Messaging.Version (mkVersionRange)
 import System.Directory (createDirectoryIfMissing, doesFileExist)
 import System.FilePath (combine)
 import System.IO (BufferMode (..), hSetBuffering, stderr, stdout)
@@ -211,10 +214,11 @@ smpServerCLI cfgPath logPath =
              smpServerVRange = supportedServerSMPRelayVRange,
              transportConfig =
                defaultTransportServerConfig
-                  { logTLSErrors = fromMaybe False $ iniOnOff "TRANSPORT" "log_tls_errors" ini,
-                    alpn = Just supportedSMPHandshakes
+                  { logTLSErrors = fromMaybe False $ iniOnOff "TRANSPORT" "log_tls_errors" ini
                  },
-              controlPort = either (const Nothing) (Just . T.unpack) $ lookupValue "TRANSPORT" "control_port" ini
+              controlPort = either (const Nothing) (Just . T.unpack) $ lookupValue "TRANSPORT" "control_port" ini,
+              smpAgentCfg = defaultSMPClientAgentConfig {smpCfg = (smpCfg defaultSMPClientAgentConfig) {serverVRange = mkVersionRange batchCmdsSMPVersion sendingProxySMPVersion, agreeSecret = True}},
+              allowSMPProxy = True -- TODO: "get from INI"
            }

 data CliCommand
@@ -306,4 +310,3 @@ cliCommandP cfgPath logPath iniFile =
      pure InitOptions {enableStoreLog, logStats, signAlgorithm, ip, fqdn, password, scripted}
    parseBasicAuth :: ReadM ServerPassword
    parseBasicAuth = eitherReader $ fmap ServerPassword . strDecode . B.pack
-
@@ -54,7 +54,7 @@ addQueue QueueStore {queues, senders} q@QueueRec {recipientId = rId, senderId =
  where
    hasId = (||) <$> TM.member rId queues <*> TM.member sId senders

-getQueue :: QueueStore -> SParty p -> QueueId -> STM (Either ErrorType QueueRec)
+getQueue :: DirectParty p => QueueStore -> SParty p -> QueueId -> STM (Either ErrorType QueueRec)
 getQueue QueueStore {queues, senders, notifiers} party qId =
  toResult <$> (mapM readTVar =<< getVar)
  where
@@ -33,17 +33,15 @@ module Simplex.Messaging.Transport
    VersionSMP,
    VersionRangeSMP,
    THandleSMP,
-    supportedSMPHandshakes,
    supportedClientSMPRelayVRange,
    supportedServerSMPRelayVRange,
-    legacyServerSMPRelayVRange,
    currentClientSMPRelayVersion,
-    legacyServerSMPRelayVersion,
    currentServerSMPRelayVersion,
    batchCmdsSMPVersion,
    basicAuthSMPVersion,
    subModeSMPVersion,
    authCmdsSMPVersion,
+    sendingProxySMPVersion,
    simplexMQVersion,
    smpBlockSize,
    TransportConfig (..),
@@ -117,6 +115,11 @@ import UnliftIO.STM

 -- * Transport parameters

+-- min size it works with:
+-- unsigned message: 16292 (paddedProxiedMsgLength = 16151, paddedForwardedMsgLength = 16239)
+-- Ed448: 16406 (16384 + 22, fails with 21)
+-- Ed25519: 16356
+-- X25519: 16381
 smpBlockSize :: Int
 smpBlockSize = 16384

@@ -152,29 +155,23 @@ subModeSMPVersion = VersionSMP 6
 authCmdsSMPVersion :: VersionSMP
 authCmdsSMPVersion = VersionSMP 7

-currentClientSMPRelayVersion :: VersionSMP
-currentClientSMPRelayVersion = VersionSMP 7
+sendingProxySMPVersion :: VersionSMP
+sendingProxySMPVersion = VersionSMP 8

-legacyServerSMPRelayVersion :: VersionSMP
-legacyServerSMPRelayVersion = VersionSMP 6
+currentClientSMPRelayVersion :: VersionSMP
+currentClientSMPRelayVersion = VersionSMP 6

 currentServerSMPRelayVersion :: VersionSMP
-currentServerSMPRelayVersion = VersionSMP 7
+currentServerSMPRelayVersion = VersionSMP 6

 -- minimal supported protocol version is 4
 -- TODO remove code that supports sending commands without batching
 supportedClientSMPRelayVRange :: VersionRangeSMP
 supportedClientSMPRelayVRange = mkVersionRange batchCmdsSMPVersion currentClientSMPRelayVersion

-legacyServerSMPRelayVRange :: VersionRangeSMP
-legacyServerSMPRelayVRange = mkVersionRange batchCmdsSMPVersion legacyServerSMPRelayVersion
-
 supportedServerSMPRelayVRange :: VersionRangeSMP
 supportedServerSMPRelayVRange = mkVersionRange batchCmdsSMPVersion currentServerSMPRelayVersion

-supportedSMPHandshakes :: [ALPN]
-supportedSMPHandshakes = ["smp/1"]
-
 simplexMQVersion :: String
 simplexMQVersion = showVersion SMQ.version

@@ -206,9 +203,6 @@ class Transport c where
  -- | tls-unique channel binding per RFC5929
  tlsUnique :: c -> SessionId

-  -- | ALPN value negotiated for the session
-  getSessionALPN :: c -> Maybe ALPN
-
  -- | Close connection
  closeConnection :: c -> IO ()

@@ -303,7 +297,6 @@ instance Transport TLS where
  getServerConnection = getTLS TServer
  getClientConnection = getTLS TClient
  getServerCerts = tlsServerCerts
-  getSessionALPN = tlsALPN
  tlsUnique = tlsUniq
  closeConnection tls = closeTLS $ tlsContext tls

@@ -370,6 +363,7 @@ data ServerHandshake = ServerHandshake
  { smpVersionRange :: VersionRangeSMP,
    sessionId :: SessionId,
    -- pub key to agree shared secrets for command authorization and entity ID encryption.
+    -- todo C.PublicKeyX25519
    authPubKey :: Maybe (X.CertificateChain, X.SignedExact X.PubKey)
  }

@@ -484,13 +478,12 @@ smpServerHandshake serverSignKey c (k, pk) kh smpVRange = do
  let th@THandle {params = THandleParams {sessionId}} = smpTHandle c
      sk = C.signX509 serverSignKey $ C.publicToX509 k
      certChain = getServerCerts c
-      smpVersionRange = maybe legacyServerSMPRelayVRange (const smpVRange) $ getSessionALPN c
-  sendHandshake th $ ServerHandshake {sessionId, smpVersionRange, authPubKey = Just (certChain, sk)}
+  sendHandshake th $ ServerHandshake {sessionId, smpVersionRange = smpVRange, authPubKey = Just (certChain, sk)}
  getHandshake th >>= \case
    ClientHandshake {smpVersion = v, keyHash, authPubKey = k'}
      | keyHash /= kh ->
          throwE $ TEHandshake IDENTITY
-      | v `isCompatible` smpVersionRange ->
+      | v `isCompatible` smpVRange ->
          pure $ smpThHandleServer th v pk k'
      | otherwise -> throwE $ TEHandshake VERSION

@@ -2,7 +2,6 @@
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE NamedFieldPuns #-}
-{-# LANGUAGE NumericUnderscores #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE ScopedTypeVariables #-}

@@ -11,7 +10,6 @@ module Simplex.Messaging.Transport.Client
    runTLSTransportClient,
    smpClientHandshake,
    defaultSMPPort,
-    defaultTcpConnectTimeout,
    defaultTransportClientConfig,
    defaultSocksProxy,
    TransportClientConfig (..),
@@ -19,7 +17,7 @@ module Simplex.Messaging.Transport.Client
    TransportHost (..),
    TransportHosts (..),
    TransportHosts_ (..),
-    validateCertificateChain,
+    validateCertificateChain
  )
 where

@@ -52,7 +50,7 @@ import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Parsers (parseAll, parseString)
 import Simplex.Messaging.Transport
 import Simplex.Messaging.Transport.KeepAlive
-import Simplex.Messaging.Util (bshow, catchAll, tshow, (<$?>))
+import Simplex.Messaging.Util (bshow, (<$?>), catchAll, tshow)
 import System.IO.Error
 import Text.Read (readMaybe)
 import UnliftIO.Exception (IOException)
@@ -114,7 +112,6 @@ instance IsString (NonEmpty TransportHost) where fromString = parseString strDec

 data TransportClientConfig = TransportClientConfig
  { socksProxy :: Maybe SocksProxy,
-    tcpConnectTimeout :: Int,
    tcpKeepAlive :: Maybe KeepAliveOpts,
    logTLSErrors :: Bool,
    clientCredentials :: Maybe (X.CertificateChain, T.PrivKey),
@@ -122,12 +119,8 @@ data TransportClientConfig = TransportClientConfig
  }
  deriving (Eq, Show)

-- time to resolve host, connect socket, set up TLS
-defaultTcpConnectTimeout :: Int
-defaultTcpConnectTimeout = 25_000_000
-
 defaultTransportClientConfig :: TransportClientConfig
-defaultTransportClientConfig = TransportClientConfig Nothing defaultTcpConnectTimeout (Just defaultKeepAliveOpts) True Nothing Nothing
+defaultTransportClientConfig = TransportClientConfig Nothing (Just defaultKeepAliveOpts) True Nothing Nothing

 clientTransportConfig :: TransportClientConfig -> TransportConfig
 clientTransportConfig TransportClientConfig {logTLSErrors} =
@@ -143,21 +136,19 @@ runTLSTransportClient tlsParams caStore_ cfg@TransportClientConfig {socksProxy,
  let hostName = B.unpack $ strEncode host
      clientParams = mkTLSClientParams tlsParams caStore_ hostName port keyHash clientCredentials alpn serverCert
      connectTCP = case socksProxy of
-        Just proxy -> connectSocksClient proxy proxyUsername (hostAddr host)
+        Just proxy -> connectSocksClient proxy proxyUsername $ hostAddr host
        _ -> connectTCPClient hostName
  c <- do
    sock <- connectTCP port
    mapM_ (setSocketKeepAlive sock) tcpKeepAlive `catchAll` \e -> logError ("Error setting TCP keep-alive" <> tshow e)
    let tCfg = clientTransportConfig cfg
-    -- No TLS timeout to avoid failing connections via SOCKS
-    tls <- connectTLS (Just hostName) tCfg clientParams sock
-    chain <-
-      atomically (tryTakeTMVar serverCert) >>= \case
+    connectTLS (Just hostName) tCfg clientParams sock >>= \tls -> do
+      chain <- atomically (tryTakeTMVar serverCert) >>= \case
        Nothing -> do
          logError "onServerCertificate didn't fire or failed to get cert chain"
          closeTLS tls >> error "onServerCertificate failed"
        Just c -> pure c
-    getClientConnection tCfg chain tls
+      getClientConnection tCfg chain tls
  client c `E.finally` closeConnection c
  where
    hostAddr = \case
@@ -24,7 +24,7 @@ import Numeric.Natural (Natural)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Transport (ALPN, SessionId, TLS (tlsALPN), getServerCerts, getServerVerifyKey, tlsUniq)
-import Simplex.Messaging.Transport.Client (TransportClientConfig (..), TransportHost (..), defaultTcpConnectTimeout, runTLSTransportClient)
+import Simplex.Messaging.Transport.Client (TransportClientConfig (..), TransportHost (..), runTLSTransportClient)
 import Simplex.Messaging.Transport.HTTP2
 import Simplex.Messaging.Util (eitherToMaybe)
 import UnliftIO.STM
@@ -70,16 +70,8 @@ defaultHTTP2ClientConfig :: HTTP2ClientConfig
 defaultHTTP2ClientConfig =
  HTTP2ClientConfig
    { qSize = 64,
-      connTimeout = defaultTcpConnectTimeout,
-      transportConfig =
-        TransportClientConfig
-          { socksProxy = Nothing,
-            tcpConnectTimeout = defaultTcpConnectTimeout,
-            tcpKeepAlive = Nothing,
-            logTLSErrors = True,
-            clientCredentials = Nothing,
-            alpn = Nothing
-          },
+      connTimeout = 10000000,
+      transportConfig = TransportClientConfig Nothing Nothing True Nothing Nothing,
      bufferSize = defaultHTTP2BufferSize,
      bodyHeadSize = 16384,
      suportedTLSParams = http2TLSParams
@@ -51,7 +51,7 @@ data HTTP2Server = HTTP2Server
 -- This server is for testing only, it processes all requests in a single queue.
 getHTTP2Server :: HTTP2ServerConfig -> IO HTTP2Server
 getHTTP2Server HTTP2ServerConfig {qSize, http2Port, bufferSize, bodyHeadSize, serverSupported, caCertificateFile, certificateFile, privateKeyFile, transportConfig} = do
-  tlsServerParams <- loadSupportedTLSServerParams serverSupported caCertificateFile certificateFile privateKeyFile (alpn transportConfig)
+  tlsServerParams <- loadSupportedTLSServerParams serverSupported caCertificateFile certificateFile privateKeyFile
  started <- newEmptyTMVarIO
  reqQ <- newTBQueueIO qSize
  action <- async $
@@ -28,10 +28,10 @@ import Control.Logger.Simple
 import Control.Monad
 import qualified Crypto.Store.X509 as SX
 import Data.Default (def)
+import Data.List (find)
 import Data.IntMap.Strict (IntMap)
 import qualified Data.IntMap.Strict as IM
-import Data.List (find)
-import Data.Maybe (fromJust, fromMaybe)
+import Data.Maybe (fromJust)
 import qualified Data.X509 as X
 import Data.X509.Validation (Fingerprint (..))
 import qualified Data.X509.Validation as XV
@@ -152,13 +152,12 @@ startTCPServer started port = withSocketsDo $ resolve >>= open >>= setStarted
      pure sock
    setStarted sock = atomically (tryPutTMVar started True) >> pure sock

-loadTLSServerParams :: FilePath -> FilePath -> FilePath -> Maybe [ALPN] -> IO T.ServerParams
+loadTLSServerParams :: FilePath -> FilePath -> FilePath -> IO T.ServerParams
 loadTLSServerParams = loadSupportedTLSServerParams supportedParameters

-loadSupportedTLSServerParams :: T.Supported -> FilePath -> FilePath -> FilePath -> Maybe [ALPN] -> IO T.ServerParams
-loadSupportedTLSServerParams serverSupported caCertificateFile certificateFile privateKeyFile alpn_ = do
-  tlsServerParams <- fromCredential <$> loadServerCredential
-  pure tlsServerParams {T.serverHooks = maybe def alpnHooks alpn_}
+loadSupportedTLSServerParams :: T.Supported -> FilePath -> FilePath -> FilePath -> IO T.ServerParams
+loadSupportedTLSServerParams serverSupported caCertificateFile certificateFile privateKeyFile =
+  fromCredential <$> loadServerCredential
  where
    loadServerCredential :: IO T.Credential
    loadServerCredential =
@@ -173,7 +172,6 @@ loadSupportedTLSServerParams serverSupported caCertificateFile certificateFile p
          T.serverHooks = def,
          T.serverSupported = serverSupported
        }
-    alpnHooks supported = def {T.onALPNClientSuggest = Just $ pure . fromMaybe "" . find (`elem` supported)}

 loadFingerprint :: FilePath -> IO Fingerprint
 loadFingerprint certificateFile = do
@@ -14,8 +14,7 @@ import Network.WebSockets
 import Network.WebSockets.Stream (Stream)
 import qualified Network.WebSockets.Stream as S
 import Simplex.Messaging.Transport
-  ( ALPN,
-    TProxy,
+  ( TProxy,
    Transport (..),
    TransportConfig (..),
    TransportError (..),
@@ -29,7 +28,6 @@ import Simplex.Messaging.Transport.Buffer (trimCR)
 data WS = WS
  { wsPeer :: TransportPeer,
    tlsUniq :: ByteString,
-    wsALPN :: Maybe ALPN,
    wsStream :: Stream,
    wsConnection :: Connection,
    wsTransportConfig :: TransportConfig,
@@ -63,9 +61,6 @@ instance Transport WS where
  getServerCerts :: WS -> X.CertificateChain
  getServerCerts = wsServerCerts

-  getSessionALPN :: WS -> Maybe ALPN
-  getSessionALPN = wsALPN
-
  tlsUnique :: WS -> ByteString
  tlsUnique = tlsUniq

@@ -95,8 +90,7 @@ getWS wsPeer cfg wsServerCerts cxt = withTlsUnique wsPeer cxt connectWS
    connectWS tlsUniq = do
      s <- makeTLSContextStream cxt
      wsConnection <- connectPeer wsPeer s
-      wsALPN <- T.getNegotiatedProtocol cxt
-      pure $ WS {wsPeer, tlsUniq, wsALPN, wsStream = s, wsConnection, wsTransportConfig = cfg, wsServerCerts}
+      pure $ WS {wsPeer, tlsUniq, wsStream = s, wsConnection, wsTransportConfig = cfg, wsServerCerts}
    connectPeer :: TransportPeer -> Stream -> IO Connection
    connectPeer TServer = acceptClientRequest
    connectPeer TClient = sendClientRequest
@@ -97,15 +97,15 @@ catchAll_ :: IO a -> IO a -> IO a
 catchAll_ a = catchAll a . const
 {-# INLINE catchAll_ #-}

-tryAllErrors :: MonadUnliftIO m => (E.SomeException -> e) -> ExceptT e m a -> ExceptT e m (Either e a)
-tryAllErrors err action = ExceptT $ Right <$> runExceptT action `UE.catch` (pure . Left . err)
+tryAllErrors :: (MonadUnliftIO m, MonadError e m) => (E.SomeException -> e) -> m a -> m (Either e a)
+tryAllErrors err action = tryError action `UE.catch` (pure . Left . err)
 {-# INLINE tryAllErrors #-}

 tryAllErrors' :: MonadUnliftIO m => (E.SomeException -> e) -> ExceptT e m a -> m (Either e a)
 tryAllErrors' err action = runExceptT action `UE.catch` (pure . Left . err)
 {-# INLINE tryAllErrors' #-}

-catchAllErrors :: MonadUnliftIO m => (E.SomeException -> e) -> ExceptT e m a -> (e -> ExceptT e m a) -> ExceptT e m a
+catchAllErrors :: (MonadUnliftIO m, MonadError e m) => (E.SomeException -> e) -> m a -> (e -> m a) -> m a
 catchAllErrors err action handler = tryAllErrors err action >>= either handler pure
 {-# INLINE catchAllErrors #-}

@@ -113,11 +113,11 @@ catchAllErrors' :: MonadUnliftIO m => (E.SomeException -> e) -> ExceptT e m a ->
 catchAllErrors' err action handler = tryAllErrors' err action >>= either handler pure
 {-# INLINE catchAllErrors' #-}

-catchThrow :: MonadUnliftIO m => ExceptT e m a -> (E.SomeException -> e) -> ExceptT e m a
+catchThrow :: (MonadUnliftIO m, MonadError e m) => m a -> (E.SomeException -> e) -> m a
 catchThrow action err = catchAllErrors err action throwError
 {-# INLINE catchThrow #-}

-allFinally :: MonadUnliftIO m => (E.SomeException -> e) -> ExceptT e m a -> ExceptT e m b -> ExceptT e m a
+allFinally :: (MonadUnliftIO m, MonadError e m) => (E.SomeException -> e) -> m a -> m b -> m a
 allFinally err action final = tryAllErrors err action >>= \r -> final >> either throwError pure r
 {-# INLINE allFinally #-}

@@ -152,14 +152,12 @@ timeoutThrow :: MonadUnliftIO m => e -> Int -> ExceptT e m a -> ExceptT e m a
 timeoutThrow e ms action = ExceptT (sequence <$> (ms `timeout` runExceptT action)) >>= maybe (throwError e) pure

 threadDelay' :: Int64 -> IO ()
-threadDelay' = loop
-  where
-    loop time
-      | time <= 0 = pure ()
-      | otherwise = do
-          let maxWait = min time $ fromIntegral (maxBound :: Int)
-          threadDelay $ fromIntegral maxWait
-          loop $ time - maxWait
+threadDelay' time
+  | time <= 0 = pure ()
+threadDelay' time = do
+  let maxWait = min time $ fromIntegral (maxBound :: Int)
+  threadDelay $ fromIntegral maxWait
+  when (maxWait /= time) $ threadDelay' (time - maxWait)

 diffToMicroseconds :: NominalDiffTime -> Int64
 diffToMicroseconds diff = fromIntegral ((truncate $ diff * 1000000) :: Integer)
@@ -27,9 +27,9 @@ import GHC.Stack (withFrozenCallStack)
 import Network.HTTP.Types (urlEncode)
 import SMPAgentClient
 import SMPClient (testKeyHash, testPort, testPort2, testStoreLogFile, withSmpServer, withSmpServerStoreLogOn)
-import Simplex.Messaging.Agent.Protocol hiding (CONF, INFO, MID, REQ)
+import Simplex.Messaging.Agent.Protocol hiding (MID, CONF, INFO, REQ)
 import qualified Simplex.Messaging.Agent.Protocol as A
-import Simplex.Messaging.Crypto.Ratchet (InitialKeys (..), PQEncryption (..), PQSupport (..), pattern IKPQOff, pattern IKPQOn, pattern PQEncOn, pattern PQSupportOff, pattern PQSupportOn)
+import Simplex.Messaging.Crypto.Ratchet (InitialKeys (..), PQEncryption (..), PQSupport (..), pattern IKPQOn, pattern IKPQOff, pattern PQEncOn, pattern PQSupportOn, pattern PQSupportOff)
 import qualified Simplex.Messaging.Crypto.Ratchet as CR
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol (ErrorType (..))
@@ -95,24 +95,23 @@ type AEntityTransmission p e = (ACorrId, ConnId, ACommand p e)
 type AEntityTransmissionOrError p e = (ACorrId, ConnId, Either AgentErrorType (ACommand p e))

 tGetAgent :: Transport c => c -> IO (AEntityTransmissionOrError 'Agent 'AEConn)
-tGetAgent = tGetAgent' True
+tGetAgent = tGetAgent'

-tGetAgent' :: forall c e. (Transport c, AEntityI e) => Bool -> c -> IO (AEntityTransmissionOrError 'Agent e)
-tGetAgent' skipErr h = do
-  (corrId, connId, cmdOrErr) <- pGetAgent skipErr h
+tGetAgent' :: forall c e. (Transport c, AEntityI e) => c -> IO (AEntityTransmissionOrError 'Agent e)
+tGetAgent' h = do
+  (corrId, connId, cmdOrErr) <- pGetAgent h
  case cmdOrErr of
    Right (APC e cmd) -> case testEquality e (sAEntity @e) of
      Just Refl -> pure (corrId, connId, Right cmd)
      _ -> error $ "unexpected command " <> show cmd
    Left err -> pure (corrId, connId, Left err)

-pGetAgent :: forall c. Transport c => Bool -> c -> IO (ATransmissionOrError 'Agent)
-pGetAgent skipErr h = do
+pGetAgent :: forall c. Transport c => c -> IO (ATransmissionOrError 'Agent)
+pGetAgent h = do
  (corrId, connId, cmdOrErr) <- tGet SAgent h
  case cmdOrErr of
-    Right (APC _ CONNECT {}) -> pGetAgent skipErr h
-    Right (APC _ DISCONNECT {}) -> pGetAgent skipErr h
-    Right (APC _ (ERR (BROKER _ NETWORK))) | skipErr -> pGetAgent skipErr h
+    Right (APC _ CONNECT {}) -> pGetAgent h
+    Right (APC _ DISCONNECT {}) -> pGetAgent h
    cmd -> pure (corrId, connId, cmd)

 -- | receive message to handle `h`
@@ -120,18 +119,15 @@ pGetAgent skipErr h = do
 (<#:) = tGetAgent

 (<#:?) :: Transport c => c -> IO (ATransmissionOrError 'Agent)
-(<#:?) = pGetAgent True
+(<#:?) = pGetAgent

 (<#:.) :: Transport c => c -> IO (AEntityTransmissionOrError 'Agent 'AENone)
-(<#:.) = tGetAgent' True
+(<#:.) = tGetAgent'

 -- | send transmission `t` to handle `h` and get response
 (#:) :: Transport c => c -> (ByteString, ByteString, ByteString) -> IO (AEntityTransmissionOrError 'Agent 'AEConn)
 h #: t = tPutRaw h t >> (<#:) h

-(#:!) :: Transport c => c -> (ByteString, ByteString, ByteString) -> IO (AEntityTransmissionOrError 'Agent 'AEConn)
-h #:! t = tPutRaw h t >> tGetAgent' False h
-
 -- | action and expected response
 -- `h #:t #> r` is the test that sends `t` to `h` and validates that the response is `r`
 (#>) :: IO (AEntityTransmissionOrError 'Agent 'AEConn) -> AEntityTransmission 'Agent 'AEConn -> Expectation
@@ -218,13 +214,14 @@ testDuplexConnection _ alice bob = testDuplexConnection' (alice, IKPQOn) (bob, P
 testDuplexConnection' :: (HasCallStack, Transport c) => (c, InitialKeys) -> (c, PQSupport) -> IO ()
 testDuplexConnection' (alice, aPQ) (bob, bPQ) = do
  let pq = pqConnectionMode aPQ bPQ
+      pqSup = CR.pqEncToSupport pq
  ("1", "bob", Right (INV cReq)) <- alice #: ("1", "bob", "NEW T INV" <> pqConnModeStr aPQ <> " subscribe")
  let cReq' = strEncode cReq
  bob #: ("11", "alice", "JOIN T " <> cReq' <> enableKEMStr bPQ <> " subscribe 14\nbob's connInfo") #> ("11", "alice", OK)
  ("", "bob", Right (A.CONF confId pqSup' _ "bob's connInfo")) <- (alice <#:)
-  pqSup' `shouldBe` CR.connPQEncryption aPQ
+  pqSup' `shouldBe` pqSup
  alice #: ("2", "bob", "LET " <> confId <> " 16\nalice's connInfo") #> ("2", "bob", OK)
-  bob <# ("", "alice", A.INFO bPQ "alice's connInfo")
+  bob <# ("", "alice", A.INFO pqSup "alice's connInfo")
  bob <# ("", "alice", CON pq)
  alice <# ("", "bob", CON pq)
  -- message IDs 1 to 3 get assigned to control messages, so first MSG is assigned ID 4
@@ -256,14 +253,15 @@ testDuplexConnRandomIds _ alice bob = testDuplexConnRandomIds' (alice, IKPQOn) (
 testDuplexConnRandomIds' :: (HasCallStack, Transport c) => (c, InitialKeys) -> (c, PQSupport) -> IO ()
 testDuplexConnRandomIds' (alice, aPQ) (bob, bPQ) = do
  let pq = pqConnectionMode aPQ bPQ
+      pqSup = CR.pqEncToSupport pq
  ("1", bobConn, Right (INV cReq)) <- alice #: ("1", "", "NEW T INV" <> pqConnModeStr aPQ <> " subscribe")
  let cReq' = strEncode cReq
  ("11", aliceConn, Right OK) <- bob #: ("11", "", "JOIN T " <> cReq' <> enableKEMStr bPQ <> " subscribe 14\nbob's connInfo")
  ("", bobConn', Right (A.CONF confId pqSup' _ "bob's connInfo")) <- (alice <#:)
-  pqSup' `shouldBe` CR.connPQEncryption aPQ
+  pqSup' `shouldBe` pqSup
  bobConn' `shouldBe` bobConn
  alice #: ("2", bobConn, "LET " <> confId <> " 16\nalice's connInfo") =#> \case ("2", c, OK) -> c == bobConn; _ -> False
-  bob <# ("", aliceConn, A.INFO bPQ "alice's connInfo")
+  bob <# ("", aliceConn, A.INFO pqSup "alice's connInfo")
  bob <# ("", aliceConn, CON pq)
  alice <# ("", bobConn, CON pq)
  alice #: ("2", bobConn, "SEND F :hello") #> ("2", bobConn, A.MID 4 pq)
@@ -293,15 +291,17 @@ testContactConnection (alice, aPQ) (bob, bPQ) (tom, tPQ) = do
  ("1", "alice_contact", Right (INV cReq)) <- alice #: ("1", "alice_contact", "NEW T CON" <> pqConnModeStr aPQ <> " subscribe")
  let cReq' = strEncode cReq
      abPQ = pqConnectionMode aPQ bPQ
+      abPQSup = CR.pqEncToSupport abPQ
      aPQMode = CR.connPQEncryption aPQ

  bob #: ("11", "alice", "JOIN T " <> cReq' <> enableKEMStr bPQ <> " subscribe 14\nbob's connInfo") #> ("11", "alice", OK)
-  ("", "alice_contact", Right (A.REQ aInvId PQSupportOn _ "bob's connInfo")) <- (alice <#:)
+  ("", "alice_contact", Right (A.REQ aInvId pqSup' _ "bob's connInfo")) <- (alice <#:)
+  pqSup' `shouldBe` bPQ
  alice #: ("2", "bob", "ACPT " <> aInvId <> enableKEMStr aPQMode <> " 16\nalice's connInfo") #> ("2", "bob", OK)
  ("", "alice", Right (A.CONF bConfId pqSup'' _ "alice's connInfo")) <- (bob <#:)
-  pqSup'' `shouldBe` bPQ
+  pqSup'' `shouldBe` abPQSup
  bob #: ("12", "alice", "LET " <> bConfId <> " 16\nbob's connInfo 2") #> ("12", "alice", OK)
-  alice <# ("", "bob", A.INFO (CR.connPQEncryption aPQ) "bob's connInfo 2")
+  alice <# ("", "bob", A.INFO abPQSup "bob's connInfo 2")
  alice <# ("", "bob", CON abPQ)
  bob <# ("", "alice", CON abPQ)
  alice #: ("3", "bob", "SEND F :hi") #> ("3", "bob", A.MID 4 abPQ)
@@ -310,13 +310,15 @@ testContactConnection (alice, aPQ) (bob, bPQ) (tom, tPQ) = do
  bob #: ("13", "alice", "ACK 4") #> ("13", "alice", OK)

  let atPQ = pqConnectionMode aPQ tPQ
+      atPQSup = CR.pqEncToSupport atPQ
  tom #: ("21", "alice", "JOIN T " <> cReq' <> enableKEMStr tPQ <> " subscribe 14\ntom's connInfo") #> ("21", "alice", OK)
-  ("", "alice_contact", Right (A.REQ aInvId' PQSupportOn _ "tom's connInfo")) <- (alice <#:)
+  ("", "alice_contact", Right (A.REQ aInvId' pqSup3 _ "tom's connInfo")) <- (alice <#:)
+  pqSup3 `shouldBe` tPQ
  alice #: ("4", "tom", "ACPT " <> aInvId' <> enableKEMStr aPQMode <> " 16\nalice's connInfo") #> ("4", "tom", OK)
  ("", "alice", Right (A.CONF tConfId pqSup4 _ "alice's connInfo")) <- (tom <#:)
-  pqSup4 `shouldBe` tPQ
+  pqSup4 `shouldBe` atPQSup
  tom #: ("22", "alice", "LET " <> tConfId <> " 16\ntom's connInfo 2") #> ("22", "alice", OK)
-  alice <# ("", "tom", A.INFO (CR.connPQEncryption aPQ) "tom's connInfo 2")
+  alice <# ("", "tom", A.INFO atPQSup "tom's connInfo 2")
  alice <# ("", "tom", CON atPQ)
  tom <# ("", "alice", CON atPQ)
  alice #: ("5", "tom", "SEND F :hi there") #> ("5", "tom", A.MID 4 atPQ)
@@ -327,20 +329,22 @@ testContactConnection (alice, aPQ) (bob, bPQ) (tom, tPQ) = do
 testContactConnRandomIds :: Transport c => (c, InitialKeys) -> (c, PQSupport) -> IO ()
 testContactConnRandomIds (alice, aPQ) (bob, bPQ) = do
  let pq = pqConnectionMode aPQ bPQ
+      pqSup = CR.pqEncToSupport pq
  ("1", aliceContact, Right (INV cReq)) <- alice #: ("1", "", "NEW T CON" <> pqConnModeStr aPQ <> " subscribe")
  let cReq' = strEncode cReq

  ("11", aliceConn, Right OK) <- bob #: ("11", "", "JOIN T " <> cReq' <> enableKEMStr bPQ <> " subscribe 14\nbob's connInfo")
-  ("", aliceContact', Right (A.REQ aInvId PQSupportOn _ "bob's connInfo")) <- (alice <#:)
+  ("", aliceContact', Right (A.REQ aInvId pqSup' _ "bob's connInfo")) <- (alice <#:)
+  pqSup' `shouldBe` bPQ
  aliceContact' `shouldBe` aliceContact

  ("2", bobConn, Right OK) <- alice #: ("2", "", "ACPT " <> aInvId <> enableKEMStr (CR.connPQEncryption aPQ) <> " 16\nalice's connInfo")
  ("", aliceConn', Right (A.CONF bConfId pqSup'' _ "alice's connInfo")) <- (bob <#:)
-  pqSup'' `shouldBe` bPQ
+  pqSup'' `shouldBe` pqSup
  aliceConn' `shouldBe` aliceConn

  bob #: ("12", aliceConn, "LET " <> bConfId <> " 16\nbob's connInfo 2") #> ("12", aliceConn, OK)
-  alice <# ("", bobConn, A.INFO (CR.connPQEncryption aPQ) "bob's connInfo 2")
+  alice <# ("", bobConn, A.INFO pqSup "bob's connInfo 2")
  alice <# ("", bobConn, CON pq)
  bob <# ("", aliceConn, CON pq)

@@ -354,7 +358,7 @@ testRejectContactRequest _ alice bob = do
  ("1", "a_contact", Right (INV cReq)) <- alice #: ("1", "a_contact", "NEW T CON subscribe")
  let cReq' = strEncode cReq
  bob #: ("11", "alice", "JOIN T " <> cReq' <> " subscribe 10\nbob's info") #> ("11", "alice", OK)
-  ("", "a_contact", Right (A.REQ aInvId PQSupportOn _ "bob's info")) <- (alice <#:)
+  ("", "a_contact", Right (A.REQ aInvId PQSupportOff _ "bob's info")) <- (alice <#:)
  -- RJCT must use correct contact connection
  alice #: ("2a", "bob", "RJCT " <> aInvId) #> ("2a", "bob", ERR $ CONN NOT_FOUND)
  alice #: ("2b", "a_contact", "RJCT " <> aInvId) #> ("2b", "a_contact", OK)
@@ -430,8 +434,8 @@ testServerConnectionAfterError t _ = do

  withAgent1 $ \bob -> do
    withAgent2 $ \alice -> do
-      bob #:! ("1", "alice", "SUB") =#> \("1", "alice", ERR (BROKER _ e)) -> e == NETWORK || e == TIMEOUT
-      alice #:! ("1", "bob", "SUB") =#> \("1", "bob", ERR (BROKER _ e)) -> e == NETWORK || e == TIMEOUT
+      bob #: ("1", "alice", "SUB") =#> \("1", "alice", ERR (BROKER _ e)) -> e == NETWORK || e == TIMEOUT
+      alice #: ("1", "bob", "SUB") =#> \("1", "bob", ERR (BROKER _ e)) -> e == NETWORK || e == TIMEOUT
      withServer $ do
        alice <#=? \case ("", "bob", APC _ (SENT 4)) -> True; ("", "", APC _ (UP s ["bob"])) -> s == server; _ -> False
        alice <#=? \case ("", "bob", APC _ (SENT 4)) -> True; ("", "", APC _ (UP s ["bob"])) -> s == server; _ -> False
@@ -551,10 +555,10 @@ testResumeDeliveryQuotaExceeded _ alice bob = do
  bob <#= \case ("", "alice", Msg "message 4") -> True; _ -> False
  bob #: ("4", "alice", "ACK 7") #> ("4", "alice", OK)
  inAnyOrder
-    (tGetAgent alice)
-    [ \case ("", c, Right (SENT 8)) -> c == "bob"; _ -> False,
-      \case ("", c, Right QCONT) -> c == "bob"; _ -> False
-    ]
+      (tGetAgent alice)
+      [ \case ("", c, Right (SENT 8)) -> c == "bob"; _ -> False,
+        \case ("", c, Right QCONT) -> c == "bob"; _ -> False
+      ]
  bob <#= \case ("", "alice", Msg "over quota") -> True; _ -> False
  -- message 8 is skipped because of alice agent sending "QCONT" message
  bob #: ("5", "alice", "ACK 9") #> ("5", "alice", OK)
@@ -567,11 +571,12 @@ connect' (h1, name1, pqMode1) (h2, name2, pqMode2) = do
  ("c1", _, Right (INV cReq)) <- h1 #: ("c1", name2, "NEW T INV" <> pqConnModeStr pqMode1 <> " subscribe")
  let cReq' = strEncode cReq
      pq = pqConnectionMode pqMode1 pqMode2
+      pqSup = CR.pqEncToSupport pq
  h2 #: ("c2", name1, "JOIN T " <> cReq' <> enableKEMStr pqMode2 <> " subscribe 5\ninfo2") #> ("c2", name1, OK)
  ("", _, Right (A.CONF connId pqSup' _ "info2")) <- (h1 <#:)
-  pqSup' `shouldBe` CR.connPQEncryption pqMode1
+  pqSup' `shouldBe` pqSup
  h1 #: ("c3", name2, "LET " <> connId <> " 5\ninfo1") #> ("c3", name2, OK)
-  h2 <# ("", name1, A.INFO pqMode2 "info1")
+  h2 <# ("", name1, A.INFO pqSup "info1")
  h2 <# ("", name1, CON pq)
  h1 <# ("", name2, CON pq)

@@ -584,7 +589,7 @@ enableKEMStr _ = ""

 pqConnModeStr :: InitialKeys -> ByteString
 pqConnModeStr (IKNoPQ PQSupportOff) = ""
-pqConnModeStr pq = " " <> strEncode pq
+pqConnModeStr pq =  " " <> strEncode pq

 sendMessage :: Transport c => (c, ConnId) -> (c, ConnId) -> ByteString -> IO ()
 sendMessage (h1, name1) (h2, name2) msg = do
@@ -68,7 +68,7 @@ testE2ERatchetParams :: RcvE2ERatchetParamsUri 'C.X448
 testE2ERatchetParams = E2ERatchetParamsUri (mkVersionRange (VersionE2E 1) (VersionE2E 1)) testDhPubKey testDhPubKey Nothing

 testE2ERatchetParams12 :: RcvE2ERatchetParamsUri 'C.X448
-testE2ERatchetParams12 = E2ERatchetParamsUri supportedE2EEncryptVRange testDhPubKey testDhPubKey Nothing
+testE2ERatchetParams12 = E2ERatchetParamsUri (supportedE2EEncryptVRange PQSupportOn) testDhPubKey testDhPubKey Nothing

 connectionRequest :: AConnectionRequestUri
 connectionRequest =
@@ -82,7 +82,7 @@ connectionRequestCurrentRange :: AConnectionRequestUri
 connectionRequestCurrentRange =
  ACR SCMInvitation $
    CRInvitationUri
-      connReqData {crAgentVRange = supportedSMPAgentVRange, crSmpQueues = [queueV1, queueV1]}
+      connReqData {crAgentVRange = supportedSMPAgentVRange PQSupportOn, crSmpQueues = [queueV1, queueV1]}
      testE2ERatchetParams12

 connectionRequestClientDataEmpty :: AConnectionRequestUri
@@ -93,9 +93,9 @@ fullMsgLen :: Ratchet a -> Int
 fullMsgLen Ratchet {rcSupportKEM, rcVersion} = headerLenLength + fullHeaderLen v 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 = case rcSupportKEM of
+      PQSupportOn | v >= pqRatchetE2EEncryptVersion -> 3 -- two bytes are added because of two Large used in new encoding
+      _ -> 1

 testMessageHeader :: forall a. AlgorithmI a => VersionE2E -> C.SAlgorithm a -> Expectation
 testMessageHeader v _ = do
@@ -520,7 +520,7 @@ initRatchets = do
  Right paramsBob <- pure $ pqX3dhSnd pkBob1 pkBob2 Nothing e2eAlice
  Right paramsAlice <- runExceptT $ pqX3dhRcv pkAlice1 pkAlice2 Nothing e2eBob
  (_, pkBob3) <- atomically $ C.generateKeyPair g
-  let vs = testRatchetVersions
+  let vs = testRatchetVersions PQSupportOff
      bob = initSndRatchet vs (C.publicKey pkAlice2) pkBob3 paramsBob
      alice = initRcvRatchet vs pkAlice2 paramsAlice PQSupportOff
  pure (alice, bob, encrypt' noSndKEM, decrypt' noRcvKEM, (\#>))
@@ -537,7 +537,7 @@ initRatchetsKEMProposed = do
  Right paramsBob <- pure $ pqX3dhSnd pkBob1 pkBob2 pKemParams_ e2eAlice
  Right paramsAlice <- runExceptT $ pqX3dhRcv pkAlice1 pkAlice2 Nothing e2eBob
  (_, pkBob3) <- atomically $ C.generateKeyPair g
-  let vs = testRatchetVersions
+  let vs = testRatchetVersions PQSupportOn
      bob = initSndRatchet vs (C.publicKey pkAlice2) pkBob3 paramsBob
      alice = initRcvRatchet vs pkAlice2 paramsAlice PQSupportOn
  pure (alice, bob, encrypt' hasSndKEM, decrypt' hasRcvKEM, (!#>))
@@ -555,7 +555,7 @@ initRatchetsKEMAccepted = do
  Right paramsBob <- pure $ pqX3dhSnd pkBob1 pkBob2 pKemParams_ e2eAlice
  Right paramsAlice <- runExceptT $ pqX3dhRcv pkAlice1 pkAlice2 pKem_ e2eBob
  (_, pkBob3) <- atomically $ C.generateKeyPair g
-  let vs = testRatchetVersions
+  let vs = testRatchetVersions PQSupportOn
      bob = initSndRatchet vs (C.publicKey pkAlice2) pkBob3 paramsBob
      alice = initRcvRatchet vs pkAlice2 paramsAlice PQSupportOn
  pure (alice, bob, encrypt' hasSndKEM, decrypt' hasRcvKEM, (!#>))
@@ -572,14 +572,14 @@ initRatchetsKEMProposedAgain = do
  Right paramsBob <- pure $ pqX3dhSnd pkBob1 pkBob2 pKemParams_ e2eAlice
  Right paramsAlice <- runExceptT $ pqX3dhRcv pkAlice1 pkAlice2 pKem_ e2eBob
  (_, pkBob3) <- atomically $ C.generateKeyPair g
-  let vs = testRatchetVersions
+  let vs = testRatchetVersions PQSupportOn
      bob = initSndRatchet vs (C.publicKey pkAlice2) pkBob3 paramsBob
      alice = initRcvRatchet vs pkAlice2 paramsAlice PQSupportOn
  pure (alice, bob, encrypt' hasSndKEM, decrypt' hasRcvKEM, (!#>))

-testRatchetVersions :: RatchetVersions
-testRatchetVersions =
-  let v = maxVersion supportedE2EEncryptVRange
+testRatchetVersions :: PQSupport -> RatchetVersions
+testRatchetVersions pq =
+  let v = maxVersion $ supportedE2EEncryptVRange pq
   in RatchetVersions v v

 encrypt_ :: AlgorithmI a => Maybe PQEncryption -> (TVar ChaChaDRG, Ratchet a, SkippedMsgKeys) -> ByteString -> IO (Either CryptoError (ByteString, Ratchet a, SkippedMsgDiff))
@@ -1,9 +1,7 @@
 {-# LANGUAGE DataKinds #-}
 {-# LANGUAGE DuplicateRecordFields #-}
 {-# LANGUAGE FlexibleContexts #-}
-{-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE GADTs #-}
-{-# LANGUAGE InstanceSigs #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE NumericUnderscores #-}
@@ -52,23 +50,22 @@ module AgentTests.FunctionalAPITests
 where

 import AgentTests.ConnectionRequestTests (connReqData, queueAddr, testE2ERatchetParams12)
-import Control.Concurrent (forkIO, killThread, threadDelay)
+import Control.Concurrent (killThread, threadDelay)
 import Control.Monad
 import Control.Monad.Except
 import Control.Monad.Reader
-import Data.Bifunctor (first)
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
 import Data.Either (isRight)
 import Data.Int (Int64)
-import Data.List (find, nub)
+import Data.List (nub)
 import Data.List.NonEmpty (NonEmpty)
 import qualified Data.Map as M
-import Data.Maybe (isJust, isNothing)
+import Data.Maybe (isNothing)
 import qualified Data.Set as S
 import Data.Time.Clock (diffUTCTime, getCurrentTime)
 import Data.Time.Clock.System (SystemTime (..), getSystemTime)
-import Data.Type.Equality (testEquality, (:~:) (Refl))
+import Data.Type.Equality
 import Data.Word (Word16)
 import qualified Database.SQLite.Simple as SQL
 import GHC.Stack (withFrozenCallStack)
@@ -80,9 +77,10 @@ import Simplex.Messaging.Agent.Client (ProtocolTestFailure (..), ProtocolTestSte
 import Simplex.Messaging.Agent.Env.SQLite (AgentConfig (..), InitialAgentServers (..), createAgentStore)
 import Simplex.Messaging.Agent.Protocol hiding (CON, CONF, INFO, REQ)
 import qualified Simplex.Messaging.Agent.Protocol as A
+import Simplex.Messaging.Agent.RetryInterval (RetryInterval (..))
 import Simplex.Messaging.Agent.Store.SQLite (MigrationConfirmation (..), SQLiteStore (dbNew))
 import Simplex.Messaging.Agent.Store.SQLite.Common (withTransaction')
-import Simplex.Messaging.Client (NetworkConfig (..), ProtocolClientConfig (..), TransportSessionMode (TSMEntity, TSMUser), defaultClientConfig)
+import Simplex.Messaging.Client (NetworkConfig (..), ProtocolClientConfig (..), TransportSessionMode (TSMEntity, TSMUser), defaultSMPClientConfig)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Crypto.Ratchet (InitialKeys (..), PQEncryption (..), PQSupport (..), pattern PQEncOff, pattern PQEncOn, pattern PQSupportOff, pattern PQSupportOn)
 import qualified Simplex.Messaging.Crypto.Ratchet as CR
@@ -92,7 +90,7 @@ import Simplex.Messaging.Protocol (BasicAuth, ErrorType (..), MsgBody, ProtocolS
 import qualified Simplex.Messaging.Protocol as SMP
 import Simplex.Messaging.Server.Env.STM (ServerConfig (..))
 import Simplex.Messaging.Server.Expiration
-import Simplex.Messaging.Transport (ATransport (..), SMPVersion, VersionSMP, authCmdsSMPVersion, basicAuthSMPVersion, batchCmdsSMPVersion, currentServerSMPRelayVersion, supportedSMPHandshakes)
+import Simplex.Messaging.Transport (ATransport (..), SMPVersion, VersionSMP, authCmdsSMPVersion, basicAuthSMPVersion, batchCmdsSMPVersion, currentServerSMPRelayVersion)
 import Simplex.Messaging.Util (diffToMicroseconds)
 import Simplex.Messaging.Version (VersionRange (..))
 import qualified Simplex.Messaging.Version as V
@@ -147,7 +145,6 @@ pGet c = do
  case cmd of
    CONNECT {} -> pGet c
    DISCONNECT {} -> pGet c
-    ERR (BROKER _ NETWORK) -> pGet c
    _ -> pure t

 pattern CONF :: ConfirmationId -> [SMPServer] -> ConnInfo -> ACommand 'Agent e
@@ -178,26 +175,22 @@ pattern Rcvd :: AgentMsgId -> ACommand 'Agent 'AEConn
 pattern Rcvd agentMsgId <- RCVD MsgMeta {integrity = MsgOk} [MsgReceipt {agentMsgId, msgRcptStatus = MROk}]

 smpCfgVPrev :: ProtocolClientConfig SMPVersion
-smpCfgVPrev = (smpCfg agentCfg) {clientALPN = Nothing, serverVRange = prevRange $ serverVRange $ smpCfg agentCfg}
+smpCfgVPrev = (smpCfg agentCfg) {serverVRange = prevRange $ serverVRange $ smpCfg agentCfg}

 smpCfgV7 :: ProtocolClientConfig SMPVersion
 smpCfgV7 = (smpCfg agentCfg) {serverVRange = V.mkVersionRange batchCmdsSMPVersion authCmdsSMPVersion}

-ntfCfgVPrev :: ProtocolClientConfig NTFVersion
-ntfCfgVPrev = (ntfCfg agentCfg) {clientALPN = Nothing, serverVRange = V.mkVersionRange (VersionNTF 1) (VersionNTF 1)}
-
 ntfCfgV2 :: ProtocolClientConfig NTFVersion
-ntfCfgV2 = (ntfCfg agentCfg) {serverVRange = V.mkVersionRange (VersionNTF 1) authBatchCmdsNTFVersion}
+ntfCfgV2 = (smpCfg agentCfg) {serverVRange = V.mkVersionRange (VersionNTF 1) authBatchCmdsNTFVersion}

 agentCfgVPrev :: AgentConfig
 agentCfgVPrev =
  agentCfg
    { sndAuthAlg = C.AuthAlg C.SEd25519,
-      smpAgentVRange = prevRange $ smpAgentVRange agentCfg,
+      smpAgentVRange = \_ -> prevRange $ smpAgentVRange agentCfg PQSupportOff,
      smpClientVRange = prevRange $ smpClientVRange agentCfg,
-      e2eEncryptVRange = prevRange $ e2eEncryptVRange agentCfg,
-      smpCfg = smpCfgVPrev,
-      ntfCfg = ntfCfgVPrev
+      e2eEncryptVRange = \_ -> prevRange $ e2eEncryptVRange agentCfg PQSupportOff,
+      smpCfg = smpCfgVPrev
    }

 -- agent config for the next client version
@@ -205,14 +198,14 @@ agentCfgV7 :: AgentConfig
 agentCfgV7 =
  agentCfg
    { sndAuthAlg = C.AuthAlg C.SX25519,
-      smpAgentVRange = V.mkVersionRange duplexHandshakeSMPAgentVersion $ max pqdrSMPAgentVersion currentSMPAgentVersion,
-      e2eEncryptVRange = V.mkVersionRange CR.kdfX3DHE2EEncryptVersion $ max CR.pqRatchetE2EEncryptVersion CR.currentE2EEncryptVersion,
+      smpAgentVRange = \_ -> V.mkVersionRange duplexHandshakeSMPAgentVersion $ max pqdrSMPAgentVersion currentSMPAgentVersion,
+      e2eEncryptVRange = \_ -> V.mkVersionRange CR.kdfX3DHE2EEncryptVersion $ max CR.pqRatchetE2EEncryptVersion CR.currentE2EEncryptVersion,
      smpCfg = smpCfgV7,
      ntfCfg = ntfCfgV2
    }

 agentCfgRatchetVPrev :: AgentConfig
-agentCfgRatchetVPrev = agentCfg {e2eEncryptVRange = prevRange $ e2eEncryptVRange agentCfg}
+agentCfgRatchetVPrev = agentCfg {e2eEncryptVRange = \_ -> prevRange $ e2eEncryptVRange agentCfg PQSupportOff}

 prevRange :: VersionRange v -> VersionRange v
 prevRange vr = vr {maxVersion = max (minVersion vr) (prevVersion $ maxVersion vr)}
@@ -251,7 +244,7 @@ createConnection :: AgentClient -> UserId -> Bool -> SConnectionMode c -> Maybe
 createConnection c userId enableNtfs cMode clientData = A.createConnection c userId enableNtfs cMode clientData (IKNoPQ PQSupportOn)

 joinConnection :: AgentClient -> UserId -> Bool -> ConnectionRequestUri c -> ConnInfo -> SubscriptionMode -> AE ConnId
-joinConnection c userId enableNtfs cReq connInfo = A.joinConnection c userId Nothing enableNtfs cReq connInfo PQSupportOn
+joinConnection c userId enableNtfs cReq connInfo = A.joinConnection c userId enableNtfs cReq connInfo PQSupportOn

 sendMessage :: AgentClient -> ConnId -> SMP.MsgFlags -> MsgBody -> AE AgentMsgId
 sendMessage c connId msgFlags msgBody = do
@@ -340,9 +333,6 @@ functionalAPITests t = do
    skip "faster version of the previous test (200 subscriptions gets very slow with test coverage)" $
      it "should subscribe to multiple (6) subscriptions with batching" $
        testBatchedSubscriptions 6 3 t
-    it "should subscribe to multiple connections with pending messages" $
-      withSmpServer t $
-        testBatchedPendingMessages 10 5
  describe "Async agent commands" $ do
    it "should connect using async agent commands" $
      withSmpServer t testAsyncCommands
@@ -438,8 +428,7 @@ functionalAPITests t = do
    it "send delivery receipts concurrently with messages" $ testDeliveryReceiptsConcurrent t
  describe "user network info" $ do
    it "should wait for user network" testWaitForUserNetwork
-    it "should not reset online to offline if happens too quickly" testDoNotResetOnlineToOffline
-    it "should resume multiple threads" testResumeMultipleThreads
+    it "should not reset offline interval while offline" testDoNotResetOfflineInterval

 testBasicAuth :: ATransport -> Bool -> (Maybe BasicAuth, VersionSMP) -> (Maybe BasicAuth, VersionSMP) -> (Maybe BasicAuth, VersionSMP) -> IO Int
 testBasicAuth t allowNewQueues srv@(srvAuth, srvVersion) clnt1 clnt2 = do
@@ -514,7 +503,7 @@ runAgentClientTest :: HasCallStack => PQSupport -> AgentClient -> AgentClient ->
 runAgentClientTest pqSupport alice@AgentClient {} bob baseId =
  runRight_ $ do
    (bobId, qInfo) <- A.createConnection alice 1 True SCMInvitation Nothing (IKNoPQ pqSupport) SMSubscribe
-    aliceId <- A.joinConnection bob 1 Nothing True qInfo "bob's connInfo" pqSupport SMSubscribe
+    aliceId <- A.joinConnection bob 1 True qInfo "bob's connInfo" pqSupport SMSubscribe
    ("", _, A.CONF confId pqSup' _ "bob's connInfo") <- get alice
    liftIO $ pqSup' `shouldBe` pqSupport
    allowConnection alice bobId confId "alice's connInfo"
@@ -557,27 +546,28 @@ testEnablePQEncryption =
    (a, 4, "msg 1") \#>\ b
    (b, 5, "msg 2") \#>\ a
    -- 45 bytes is used by agent message envelope inside double ratchet message envelope
-    let largeMsg g' pqEnc = atomically $ C.randomBytes (e2eEncAgentMsgLength pqdrSMPAgentVersion pqEnc - 45) g'
+    let largeMsg g' pqEnc = atomically $ C.randomBytes (e2eEncUserMsgLength pqdrSMPAgentVersion pqEnc - 45) g'
    lrg <- largeMsg g PQSupportOff
    (a, 6, lrg) \#>\ b
    (b, 7, lrg) \#>\ a
+    -- enabling PQ encryption
+    (a, 8, lrg) \#>! b
+    (b, 9, lrg) \#>! a
    -- switched to smaller envelopes (before reporting PQ encryption enabled)
    sml <- largeMsg g PQSupportOn
    -- fail because of message size
    Left (A.CMD LARGE) <- tryError $ A.sendMessage ca bId PQEncOn SMP.noMsgFlags lrg
-    (9, PQEncOff) <- A.sendMessage ca bId PQEncOn SMP.noMsgFlags sml
-    get ca =##> \case ("", connId, SENT 9) -> connId == bId; _ -> False
-    get cb =##> \case ("", connId, MsgErr' 8 MsgSkipped {} PQEncOff msg') -> connId == aId && msg' == sml; _ -> False
-    ackMessage cb aId 8 Nothing
+    (11, PQEncOff) <- A.sendMessage ca bId PQEncOn SMP.noMsgFlags sml
+    get ca =##> \case ("", connId, SENT 11) -> connId == bId; _ -> False
+    get cb =##> \case ("", connId, MsgErr' 10 MsgSkipped {} PQEncOff msg') -> connId == aId && msg' == sml; _ -> False
+    ackMessage cb aId 10 Nothing
    -- -- fail in reply to sync IDss
    Left (A.CMD LARGE) <- tryError $ A.sendMessage cb aId PQEncOn SMP.noMsgFlags lrg
-    (10, PQEncOff) <- A.sendMessage cb aId PQEncOn SMP.noMsgFlags sml
-    get cb =##> \case ("", connId, SENT 10) -> connId == aId; _ -> False
-    get ca =##> \case ("", connId, MsgErr' 10 MsgSkipped {} PQEncOff msg') -> connId == bId && msg' == sml; _ -> False
-    ackMessage ca bId 10 Nothing
-    (a, 11, sml) \#>! b
+    (12, PQEncOn) <- A.sendMessage cb aId PQEncOn SMP.noMsgFlags sml
+    get cb =##> \case ("", connId, SENT 12) -> connId == aId; _ -> False
+    get ca =##> \case ("", connId, MsgErr' 12 MsgSkipped {} PQEncOn msg') -> connId == bId && msg' == sml; _ -> False
+    ackMessage ca bId 12 Nothing
    -- PQ encryption now enabled
-    (b, 12, sml) !#>! a
    (a, 13, sml) !#>! b
    (b, 14, sml) !#>! a
    -- disabling PQ encryption
@@ -641,9 +631,7 @@ runAgentClientContactTest :: HasCallStack => PQSupport -> AgentClient -> AgentCl
 runAgentClientContactTest pqSupport alice bob baseId =
  runRight_ $ do
    (_, qInfo) <- A.createConnection alice 1 True SCMContact Nothing (IKNoPQ pqSupport) SMSubscribe
-    aliceId <- A.prepareConnectionToJoin bob 1 True qInfo pqSupport
-    aliceId' <- A.joinConnection bob 1 (Just aliceId) True qInfo "bob's connInfo" pqSupport SMSubscribe
-    liftIO $ aliceId' `shouldBe` aliceId
+    aliceId <- A.joinConnection bob 1 True qInfo "bob's connInfo" pqSupport SMSubscribe
    ("", _, A.REQ invId pqSup' _ "bob's connInfo") <- get alice
    liftIO $ pqSup' `shouldBe` pqSupport
    bobId <- acceptContact alice True invId "alice's connInfo" PQSupportOn SMSubscribe
@@ -809,8 +797,8 @@ testAllowConnectionClientRestart t = do

 testIncreaseConnAgentVersion :: HasCallStack => ATransport -> IO ()
 testIncreaseConnAgentVersion t = do
-  alice <- getSMPAgentClient' 1 agentCfg {smpAgentVRange = mkVersionRange 1 2} initAgentServers testDB
-  bob <- getSMPAgentClient' 2 agentCfg {smpAgentVRange = mkVersionRange 1 2} initAgentServers testDB2
+  alice <- getSMPAgentClient' 1 agentCfg {smpAgentVRange = \_ -> mkVersionRange 1 2} initAgentServers testDB
+  bob <- getSMPAgentClient' 2 agentCfg {smpAgentVRange = \_ -> mkVersionRange 1 2} initAgentServers testDB2
  withSmpServerStoreMsgLogOn t testPort $ \_ -> do
    (aliceId, bobId) <- runRight $ do
      (aliceId, bobId) <- makeConnection_ PQSupportOff alice bob
@@ -822,7 +810,7 @@ testIncreaseConnAgentVersion t = do
    -- version doesn't increase if incompatible

    disposeAgentClient alice
-    alice2 <- getSMPAgentClient' 3 agentCfg {smpAgentVRange = mkVersionRange 1 3} initAgentServers testDB
+    alice2 <- getSMPAgentClient' 3 agentCfg {smpAgentVRange = \_ -> mkVersionRange 1 3} initAgentServers testDB

    runRight_ $ do
      subscribeConnection alice2 bobId
@@ -833,7 +821,7 @@ testIncreaseConnAgentVersion t = do
    -- version increases if compatible

    disposeAgentClient bob
-    bob2 <- getSMPAgentClient' 4 agentCfg {smpAgentVRange = mkVersionRange 1 3} initAgentServers testDB2
+    bob2 <- getSMPAgentClient' 4 agentCfg {smpAgentVRange = \_ -> mkVersionRange 1 3} initAgentServers testDB2

    runRight_ $ do
      subscribeConnection bob2 aliceId
@@ -844,7 +832,7 @@ testIncreaseConnAgentVersion t = do
    -- version doesn't decrease, even if incompatible

    disposeAgentClient alice2
-    alice3 <- getSMPAgentClient' 5 agentCfg {smpAgentVRange = mkVersionRange 2 2} initAgentServers testDB
+    alice3 <- getSMPAgentClient' 5 agentCfg {smpAgentVRange = \_ -> mkVersionRange 2 2} initAgentServers testDB

    runRight_ $ do
      subscribeConnection alice3 bobId
@@ -853,7 +841,7 @@ testIncreaseConnAgentVersion t = do
      checkVersion bob2 aliceId 3

    disposeAgentClient bob2
-    bob3 <- getSMPAgentClient' 6 agentCfg {smpAgentVRange = mkVersionRange 1 1} initAgentServers testDB2
+    bob3 <- getSMPAgentClient' 6 agentCfg {smpAgentVRange = \_ -> mkVersionRange 1 1} initAgentServers testDB2

    runRight_ $ do
      subscribeConnection bob3 aliceId
@@ -870,8 +858,8 @@ checkVersion c connId v = do

 testIncreaseConnAgentVersionMaxCompatible :: HasCallStack => ATransport -> IO ()
 testIncreaseConnAgentVersionMaxCompatible t = do
-  alice <- getSMPAgentClient' 1 agentCfg {smpAgentVRange = mkVersionRange 1 2} initAgentServers testDB
-  bob <- getSMPAgentClient' 2 agentCfg {smpAgentVRange = mkVersionRange 1 2} initAgentServers testDB2
+  alice <- getSMPAgentClient' 1 agentCfg {smpAgentVRange = \_ -> mkVersionRange 1 2} initAgentServers testDB
+  bob <- getSMPAgentClient' 2 agentCfg {smpAgentVRange = \_ -> mkVersionRange 1 2} initAgentServers testDB2
  withSmpServerStoreMsgLogOn t testPort $ \_ -> do
    (aliceId, bobId) <- runRight $ do
      (aliceId, bobId) <- makeConnection_ PQSupportOff alice bob
@@ -883,7 +871,7 @@ testIncreaseConnAgentVersionMaxCompatible t = do
    -- version increases to max compatible

    disposeAgentClient alice
-    alice2 <- getSMPAgentClient' 3 agentCfg {smpAgentVRange = mkVersionRange 1 3} initAgentServers testDB
+    alice2 <- getSMPAgentClient' 3 agentCfg {smpAgentVRange = \_ -> mkVersionRange 1 3} initAgentServers testDB
    disposeAgentClient bob
    bob2 <- getSMPAgentClient' 4 agentCfg {smpAgentVRange = supportedSMPAgentVRange} initAgentServers testDB2

@@ -898,8 +886,8 @@ testIncreaseConnAgentVersionMaxCompatible t = do

 testIncreaseConnAgentVersionStartDifferentVersion :: HasCallStack => ATransport -> IO ()
 testIncreaseConnAgentVersionStartDifferentVersion t = do
-  alice <- getSMPAgentClient' 1 agentCfg {smpAgentVRange = mkVersionRange 1 2} initAgentServers testDB
-  bob <- getSMPAgentClient' 2 agentCfg {smpAgentVRange = mkVersionRange 1 3} initAgentServers testDB2
+  alice <- getSMPAgentClient' 1 agentCfg {smpAgentVRange = \_ -> mkVersionRange 1 2} initAgentServers testDB
+  bob <- getSMPAgentClient' 2 agentCfg {smpAgentVRange = \_ -> mkVersionRange 1 3} initAgentServers testDB2
  withSmpServerStoreMsgLogOn t testPort $ \_ -> do
    (aliceId, bobId) <- runRight $ do
      (aliceId, bobId) <- makeConnection_ PQSupportOff alice bob
@@ -911,7 +899,7 @@ testIncreaseConnAgentVersionStartDifferentVersion t = do
    -- version increases to max compatible

    disposeAgentClient alice
-    alice2 <- getSMPAgentClient' 3 agentCfg {smpAgentVRange = mkVersionRange 1 3} initAgentServers testDB
+    alice2 <- getSMPAgentClient' 3 agentCfg {smpAgentVRange = \_ -> mkVersionRange 1 3} initAgentServers testDB

    runRight_ $ do
      subscribeConnection alice2 bobId
@@ -1412,9 +1400,7 @@ makeConnectionForUsers = makeConnectionForUsers_ PQSupportOn
 makeConnectionForUsers_ :: PQSupport -> AgentClient -> UserId -> AgentClient -> UserId -> ExceptT AgentErrorType IO (ConnId, ConnId)
 makeConnectionForUsers_ pqSupport alice aliceUserId bob bobUserId = do
  (bobId, qInfo) <- A.createConnection alice aliceUserId True SCMInvitation Nothing (CR.IKNoPQ pqSupport) SMSubscribe
-  aliceId <- A.prepareConnectionToJoin bob bobUserId True qInfo pqSupport
-  aliceId' <- A.joinConnection bob bobUserId (Just aliceId) True qInfo "bob's connInfo" pqSupport SMSubscribe
-  liftIO $ aliceId' `shouldBe` aliceId
+  aliceId <- A.joinConnection bob bobUserId True qInfo "bob's connInfo" pqSupport SMSubscribe
  ("", _, A.CONF confId pqSup' _ "bob's connInfo") <- get alice
  liftIO $ pqSup' `shouldBe` pqSupport
  allowConnection alice bobId confId "alice's connInfo"
@@ -1541,7 +1527,7 @@ testBatchedSubscriptions :: Int -> Int -> ATransport -> IO ()
 testBatchedSubscriptions nCreate nDel t =
  withAgentClientsCfgServers2 agentCfg agentCfg initAgentServers2 $ \a b -> do
    conns <- runServers $ do
-      conns <- replicateM nCreate $ makeConnection_ PQSupportOff a b
+      conns <- replicateM (nCreate :: Int) $ makeConnection_ PQSupportOff a b
      forM_ conns $ \(aId, bId) -> exchangeGreetings_ PQEncOff a bId b aId
      let (aIds', bIds') = unzip $ take nDel conns
      delete a bIds'
@@ -1600,25 +1586,6 @@ testBatchedSubscriptions nCreate nDel t =
        killThread t1
        pure res

-testBatchedPendingMessages :: Int -> Int -> IO ()
-testBatchedPendingMessages nCreate nMsgs =
-  withA $ \a -> do
-    conns <- withB $ \b -> runRight $ do
-      replicateM nCreate $ makeConnection a b
-    let msgConns = take nMsgs conns
-    runRight_ $ forM_ msgConns $ \(_, bId) -> sendMessage a bId SMP.noMsgFlags "hello"
-    replicateM_ nMsgs $ get a =##> \case ("", cId, SENT _) -> isJust $ find ((cId ==) . snd) msgConns; _ -> False
-    withB $ \b -> runRight_ $ do
-      r <- subscribeConnections b $ map fst conns
-      liftIO $ all isRight r `shouldBe` True
-      replicateM_ nMsgs $ do
-        ("", cId, Msg' msgId _ "hello") <- get b
-        liftIO $ isJust (find ((cId ==) . fst) msgConns) `shouldBe` True
-        ackMessage b cId msgId Nothing
-  where
-    withA = withAgent 1 agentCfg initAgentServers testDB
-    withB = withAgent 2 agentCfg initAgentServers testDB2
-
 testAsyncCommands :: IO ()
 testAsyncCommands =
  withAgentClients2 $ \alice bob -> runRight_ $ do
@@ -2446,8 +2413,7 @@ testCreateQueueAuth srvVersion clnt1 clnt2 = do
  where
    getClient clientId (clntAuth, clntVersion) db =
      let servers = initAgentServers {smp = userServers [ProtoServerWithAuth testSMPServer clntAuth]}
-          alpn_ = if clntVersion >= authCmdsSMPVersion then Just supportedSMPHandshakes else Nothing
-          smpCfg = defaultClientConfig alpn_ $ V.mkVersionRange (prevVersion basicAuthSMPVersion) clntVersion
+          smpCfg = (defaultSMPClientConfig :: ProtocolClientConfig SMPVersion) {serverVRange = V.mkVersionRange (prevVersion basicAuthSMPVersion) clntVersion}
          sndAuthAlg = if srvVersion >= authCmdsSMPVersion && clntVersion >= authCmdsSMPVersion then C.AuthAlg C.SX25519 else C.AuthAlg C.SEd25519
       in getSMPAgentClient' clientId agentCfg {smpCfg, sndAuthAlg} servers db

@@ -2488,8 +2454,8 @@ testDeliveryReceipts =

 testDeliveryReceiptsVersion :: HasCallStack => ATransport -> IO ()
 testDeliveryReceiptsVersion t = do
-  a <- getSMPAgentClient' 1 agentCfg {smpAgentVRange = mkVersionRange 1 3} initAgentServers testDB
-  b <- getSMPAgentClient' 2 agentCfg {smpAgentVRange = mkVersionRange 1 3} initAgentServers testDB2
+  a <- getSMPAgentClient' 1 agentCfg {smpAgentVRange = \_ -> mkVersionRange 1 3} initAgentServers testDB
+  b <- getSMPAgentClient' 2 agentCfg {smpAgentVRange = \_ -> mkVersionRange 1 3} initAgentServers testDB2
  withSmpServerStoreMsgLogOn t testPort $ \_ -> do
    (aId, bId) <- runRight $ do
      (aId, bId) <- makeConnection_ PQSupportOff a b
@@ -2516,8 +2482,8 @@ testDeliveryReceiptsVersion t = do
      subscribeConnection a' bId
      subscribeConnection b' aId
      exchangeGreetingsMsgId_ PQEncOff 6 a' bId b' aId
-      checkVersion a' bId 5
-      checkVersion b' aId 5
+      checkVersion a' bId 4
+      checkVersion b' aId 4
      (8, PQEncOff) <- A.sendMessage a' bId PQEncOn SMP.noMsgFlags "hello"
      get a' ##> ("", bId, SENT 8)
      get b' =##> \case ("", c, Msg' 8 PQEncOff "hello") -> c == aId; _ -> False
@@ -2702,7 +2668,9 @@ testWaitForUserNetwork = do
  noNetworkDelay a
  setUserNetworkInfo a $ UserNetworkInfo UNNone False
  networkDelay a 100000
-  networkDelay a 100000
+  networkDelay a 150000
+  networkDelay a 200000
+  networkDelay a 200000
  setUserNetworkInfo a $ UserNetworkInfo UNCellular True
  noNetworkDelay a
  setUserNetworkInfo a $ UserNetworkInfo UNCellular False
@@ -2712,66 +2680,36 @@ testWaitForUserNetwork = do
    (networkDelay a 50000)
  noNetworkDelay a
  where
-    aCfg = agentCfg {userNetworkInterval = 100000, userOfflineDelay = 0}
+    aCfg = agentCfg {userNetworkInterval = RetryInterval {initialInterval = 100000, increaseAfter = 0, maxInterval = 200000}}

-testDoNotResetOnlineToOffline :: IO ()
-testDoNotResetOnlineToOffline = do
+testDoNotResetOfflineInterval :: IO ()
+testDoNotResetOfflineInterval = do
  a <- getSMPAgentClient' 1 aCfg initAgentServers testDB
  noNetworkDelay a
  setUserNetworkInfo a $ UserNetworkInfo UNWifi False
  networkDelay a 100000
-  setUserNetworkInfo a $ UserNetworkInfo UNWifi False
-  setUserNetworkInfo a $ UserNetworkInfo UNWifi True
-  noNetworkDelay a
-  setUserNetworkInfo a $ UserNetworkInfo UNWifi False -- ingnored
-  noNetworkDelay a
-  threadDelay 100000
-  setUserNetworkInfo a $ UserNetworkInfo UNWifi False
-  networkDelay a 100000
+  networkDelay a 150000
+  setUserNetworkInfo a $ UserNetworkInfo UNCellular False
+  networkDelay a 200000
  setUserNetworkInfo a $ UserNetworkInfo UNNone False
-  networkDelay a 100000
-  setUserNetworkInfo a $ UserNetworkInfo UNWifi True
-  setUserNetworkInfo a $ UserNetworkInfo UNNone False -- ingnored
-  noNetworkDelay a
-  where
-    aCfg = agentCfg {userNetworkInterval = 100000, userOfflineDelay = 0.1}
-
-testResumeMultipleThreads :: IO ()
-testResumeMultipleThreads = do
-  a <- getSMPAgentClient' 1 aCfg initAgentServers testDB
-  noNetworkDelay a
-  setUserNetworkInfo a $ UserNetworkInfo UNNone False
-  vs <-
-    replicateM 50000 $ do
-      v <- newEmptyTMVarIO
-      void . forkIO $ waitNetwork a >>= atomically . putTMVar v
-      pure v
-  threadDelay 1000000
+  networkDelay a 200000
  setUserNetworkInfo a $ UserNetworkInfo UNCellular True
-  ts <- mapM (atomically . readTMVar) vs
-  -- print $ minimum ts
-  -- print $ maximum ts
-  -- print $ sum ts `div` fromIntegral (length ts)
-  let average = sum ts `div` fromIntegral (length ts)
-  average < 3000000 `shouldBe` True
-  maximum ts < 4000000 `shouldBe` True
+  noNetworkDelay a
+  setUserNetworkInfo a $ UserNetworkInfo UNCellular False
+  networkDelay a 100000
  where
-    aCfg = agentCfg {userOfflineDelay = 0}
+    aCfg = agentCfg {userNetworkInterval = RetryInterval {initialInterval = 100000, increaseAfter = 0, maxInterval = 200000}}

 noNetworkDelay :: AgentClient -> IO ()
-noNetworkDelay a = do
-  d <- waitNetwork a
-  unless (d < 10000) $ expectationFailure $ "expected no delay, d = " <> show d
+noNetworkDelay a = (10000 >) <$> waitNetwork a `shouldReturn` True

 networkDelay :: AgentClient -> Int64 -> IO ()
-networkDelay a d' = do
-  d <- waitNetwork a
-  unless (d' < d && d < d' + 15000) $ expectationFailure $ "expected delay " <> show d' <> ", d = " <> show d
+networkDelay a d' = (\d -> d' < d && d < d' + 15000) <$> waitNetwork a `shouldReturn` True

 waitNetwork :: AgentClient -> IO Int64
 waitNetwork a = do
  t <- getCurrentTime
-  waitForUserNetwork a
+  waitForUserNetwork a `runReaderT` agentEnv a
  t' <- getCurrentTime
  pure $ diffToMicroseconds $ diffUTCTime t' t

@@ -2812,16 +2750,3 @@ exchangeGreetingsMsgIds alice bobId aliceMsgId bob aliceId bobMsgId = do
  get bob ##> ("", aliceId, SENT bobMsgId')
  get alice =##> \case ("", c, Msg "hello too") -> c == bobId; _ -> False
  ackMessage alice bobId aliceMsgId' Nothing
-
-newtype InternalException e = InternalException {unInternalException :: e}
-  deriving (Eq, Show)
-
-instance Exception e => Exception (InternalException e)
-
-instance Exception e => MonadUnliftIO (ExceptT e IO) where
-  {-# INLINE withRunInIO #-}
-  withRunInIO :: ((forall a. ExceptT e IO a -> IO a) -> IO b) -> ExceptT e IO b
-  withRunInIO inner =
-    ExceptT . fmap (first unInternalException) . try $
-      withRunInIO $ \run ->
-        inner $ run . (either (throwIO . InternalException) pure <=< runExceptT)
@@ -6,8 +6,8 @@
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE PatternSynonyms #-}
 {-# LANGUAGE TypeApplications #-}
-{-# OPTIONS_GHC -fno-warn-ambiguous-fields #-}
 {-# OPTIONS_GHC -fno-warn-incomplete-uni-patterns #-}
+{-# OPTIONS_GHC -fno-warn-ambiguous-fields #-}

 module AgentTests.NotificationTests where

@@ -17,6 +17,10 @@ import AgentTests.FunctionalAPITests
    createConnection,
    exchangeGreetingsMsgId,
    get,
+    withAgent,
+    withAgentClients2,
+    withAgentClientsCfgServers2,
+    withAgentClients3,
    joinConnection,
    makeConnection,
    nGet,
@@ -25,11 +29,7 @@ import AgentTests.FunctionalAPITests
    sendMessage,
    switchComplete,
    testServerMatrix2,
-    withAgent,
-    withAgentClients2,
-    withAgentClients3,
    withAgentClientsCfg2,
-    withAgentClientsCfgServers2,
    (##>),
    (=##>),
    pattern CON,
@@ -59,8 +59,8 @@ import Simplex.Messaging.Agent.Protocol hiding (CON, CONF, INFO)
 import Simplex.Messaging.Agent.Store.SQLite (getSavedNtfToken)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding.String
-import Simplex.Messaging.Notifications.Protocol
 import Simplex.Messaging.Notifications.Server.Env (NtfServerConfig (..))
+import Simplex.Messaging.Notifications.Protocol
 import Simplex.Messaging.Notifications.Server.Push.APNS
 import Simplex.Messaging.Notifications.Types (NtfToken (..))
 import Simplex.Messaging.Protocol (ErrorType (AUTH), MsgFlags (MsgFlags), NtfServer, ProtocolServer (..), SMPMsgMeta (..), SubscriptionMode (..))
@@ -151,8 +151,7 @@ testNtfMatrix t runTest = do
    it "next servers: SMP v7, NTF v2; curr clients: v6/v1" $ runNtfTestCfg t cfgV7 ntfServerCfgV2 agentCfg agentCfg runTest
    it "curr servers: SMP v6, NTF v1; curr clients: v6/v1" $ runNtfTestCfg t cfg ntfServerCfg agentCfg agentCfg runTest
    skip "this case cannot be supported - see RFC" $
-      it "servers: SMP v6, NTF v1; clients: v7/v2 (not supported)" $
-        runNtfTestCfg t cfg ntfServerCfg agentCfgV7 agentCfgV7 runTest
+      it "servers: SMP v6, NTF v1; clients: v7/v2 (not supported)" $ runNtfTestCfg t cfg ntfServerCfg agentCfgV7 agentCfgV7 runTest
    -- servers can be migrated in any order
    it "servers: next SMP v7, curr NTF v1; curr clients: v6/v1" $ runNtfTestCfg t cfgV7 ntfServerCfg agentCfg agentCfg runTest
    it "servers: curr SMP v6, next NTF v2; curr clients: v6/v1" $ runNtfTestCfg t cfg ntfServerCfgV2 agentCfg agentCfg runTest
@@ -259,7 +258,7 @@ testNtfTokenServerRestart t APNSMockServer {apnsQ} = do
        atomically $ readTBQueue apnsQ
      liftIO $ sendApnsResponse APNSRespOk
      pure ntfData
-  -- the new agent is created as otherwise when running the tests in CI the old agent was keeping the connection to the server
+    -- the new agent is created as otherwise when running the tests in CI the old agent was keeping the connection to the server
  threadDelay 1000000
  withAgent 2 agentCfg initAgentServers testDB $ \a' ->
    -- server stopped before token is verified, so now the attempt to verify it will return AUTH error but re-register token,
@@ -281,12 +281,12 @@ randomSUB_ :: (C.AlgorithmI a, C.AuthAlgorithm a) => C.SAlgorithm a -> VersionSM
 randomSUB_ a v sessId = do
  g <- C.newRandom
  rId <- atomically $ C.randomBytes 24 g
-  corrId <- atomically $ CorrId <$> 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
-      TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth thParams (corrId, rId, Cmd SRecipient SUB)
-  pure $ (,tToSend) <$> authTransmission thAuth_ (Just rpKey) corrId tForAuth
+      TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth thParams (CorrId corrId, rId, Cmd SRecipient SUB)
+  pure $ (,tToSend) <$> authTransmission thAuth_ (Just rpKey) nonce tForAuth

 randomSUBCmd :: ProtocolClient SMPVersion ErrorType BrokerMsg -> IO (PCTransmission ErrorType BrokerMsg)
 randomSUBCmd = randomSUBCmd_ C.SEd25519
@@ -311,13 +311,13 @@ randomSEND_ :: (C.AlgorithmI a, C.AuthAlgorithm a) => C.SAlgorithm a -> VersionS
 randomSEND_ a v sessId len = do
  g <- C.newRandom
  sId <- atomically $ C.randomBytes 24 g
-  corrId <- atomically $ CorrId <$> C.randomBytes 3 g
+  nonce@(C.CbNonce corrId) <- atomically $ C.randomCbNonce g
  (sKey, spKey) <- atomically $ C.generateAuthKeyPair a g
  thAuth_ <- testTHandleAuth v g sKey
  msg <- atomically $ C.randomBytes len g
  let thParams = testTHandleParams v sessId
-      TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth thParams (corrId, sId, Cmd SSender $ SEND noMsgFlags msg)
-  pure $ (,tToSend) <$> authTransmission thAuth_ (Just spKey) corrId tForAuth
+      TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth thParams (CorrId corrId, sId, Cmd SSender $ SEND noMsgFlags msg)
+  pure $ (,tToSend) <$> authTransmission thAuth_ (Just spKey) nonce tForAuth

 testTHandleParams :: VersionSMP -> ByteString -> THandleParams SMPVersion 'TClient
 testTHandleParams v sessionId =
@@ -2,7 +2,6 @@
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE StandaloneDeriving #-}
-{-# LANGUAGE TypeApplications #-}
 {-# OPTIONS_GHC -Wno-orphans #-}

 module CoreTests.ProtocolErrorTests where
@@ -14,9 +13,11 @@ import GHC.Generics (Generic)
 import Generic.Random (genericArbitraryU)
 import Simplex.FileTransfer.Transport (XFTPErrorType (..))
 import Simplex.Messaging.Agent.Protocol
+import qualified Simplex.Messaging.Agent.Protocol as Agent
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
-import Simplex.Messaging.Protocol (CommandError (..), ErrorType (..))
+import Simplex.Messaging.Protocol (CommandError (..), ErrorType (..), ProxyError (..))
+import qualified Simplex.Messaging.Protocol as SMP
 import Simplex.Messaging.Transport (HandshakeError (..), TransportError (..))
 import Simplex.RemoteControl.Types (RCErrorType (..))
 import Test.Hspec
@@ -28,15 +29,19 @@ protocolErrorTests = modifyMaxSuccess (const 1000) $ do
  describe "errors parsing / serializing" $ do
    it "should parse SMP protocol errors" . property $ \(err :: ErrorType) ->
      smpDecode (smpEncode err) == Right err
-    it "should parse SMP agent errors" . property $ \(err :: AgentErrorType) ->
-      errHasSpaces err
-        || strDecode (strEncode err) == Right err
+    it "should parse SMP agent errors" . property . forAll possible $ \err ->
+      strDecode (strEncode err) == Right err
  where
-    errHasSpaces = \case
-      BROKER srv (RESPONSE e) -> hasSpaces srv || hasSpaces e
-      BROKER srv _ -> hasSpaces srv
-      _ -> False
+    possible :: Gen AgentErrorType
+    possible =
+      arbitrary >>= \case
+        BROKER srv (Agent.RESPONSE e) | hasSpaces srv || hasSpaces e -> discard
+        BROKER srv _ | hasSpaces srv -> discard
+        SMP (PROXY (SMP.UNEXPECTED s)) | hasUnicode s -> discard
+        NTF (PROXY (SMP.UNEXPECTED s)) | hasUnicode s -> discard
+        ok -> pure ok
    hasSpaces s = ' ' `B.elem` encodeUtf8 (T.pack s)
+    hasUnicode = any (>= '\255')

 deriving instance Generic AgentErrorType

@@ -54,6 +59,8 @@ deriving instance Generic ErrorType

 deriving instance Generic CommandError

+deriving instance Generic ProxyError
+
 deriving instance Generic TransportError

 deriving instance Generic HandshakeError
@@ -78,6 +85,8 @@ instance Arbitrary ErrorType where arbitrary = genericArbitraryU

 instance Arbitrary CommandError where arbitrary = genericArbitraryU

+instance Arbitrary ProxyError where arbitrary = genericArbitraryU
+
 instance Arbitrary TransportError where arbitrary = genericArbitraryU

 instance Arbitrary HandshakeError where arbitrary = genericArbitraryU
@@ -22,13 +22,10 @@ tRcvQueuesTests = do
  describe "connection API" $ do
    it "hasConn" hasConnTest
    it "hasConn, batch add" hasConnTestBatch
-    it "hasConn, batch idempotent" batchIdempotentTest
    it "deleteConn" deleteConnTest
  describe "session API" $ do
    it "getSessQueues" getSessQueuesTest
    it "getDelSessQueues" getDelSessQueuesTest
-  describe "queue transfer" $ do
-    it "getDelSessQueues-batchAddQueues preserves total length" removeSubsTest

 checkDataInvariant :: RQ.TRcvQueues -> IO Bool
 checkDataInvariant trq = atomically $ do
@@ -65,19 +62,6 @@ hasConnTestBatch = do
  atomically (RQ.hasConn "c3" trq) `shouldReturn` True
  atomically (RQ.hasConn "nope" trq) `shouldReturn` False

-batchIdempotentTest :: IO ()
-batchIdempotentTest = do
-  trq <- atomically RQ.empty
-  let qs = [dummyRQ 0 "smp://1234-w==@alpha" "c1", dummyRQ 0 "smp://1234-w==@alpha" "c2", dummyRQ 0 "smp://1234-w==@beta" "c3"]
-  atomically $ RQ.batchAddQueues trq qs
-  checkDataInvariant trq `shouldReturn` True
-  qs' <- readTVarIO $ RQ.getRcvQueues trq
-  cs' <- readTVarIO $ RQ.getConnections trq
-  atomically $ RQ.batchAddQueues trq qs
-  checkDataInvariant trq `shouldReturn` True
-  readTVarIO (RQ.getRcvQueues trq) `shouldReturn` qs'
-  fmap L.nub <$> readTVarIO (RQ.getConnections trq) `shouldReturn`cs' -- connections get duplicated, but that doesn't appear to affect anybody
-
 deleteConnTest :: IO ()
 deleteConnTest = do
  trq <- atomically RQ.empty
@@ -137,40 +121,6 @@ getDelSessQueuesTest = do
  atomically (RQ.hasConn "c3" trq) `shouldReturn` True
  atomically (RQ.hasConn "c4" trq) `shouldReturn` True

-removeSubsTest :: IO ()
-removeSubsTest = do
-  aq <- atomically RQ.empty
-  let qs =
-        [ dummyRQ 0 "smp://1234-w==@alpha" "c1",
-          dummyRQ 0 "smp://1234-w==@alpha" "c2",
-          dummyRQ 0 "smp://1234-w==@beta" "c3",
-          dummyRQ 1 "smp://1234-w==@beta" "c4"
-        ]
-  atomically $ RQ.batchAddQueues aq qs
-
-  pq <- atomically RQ.empty
-  atomically (totalSize aq pq) `shouldReturn` (4, 4)
-
-  atomically $ RQ.getDelSessQueues (0, "smp://1234-w==@alpha", Nothing) aq >>= RQ.batchAddQueues pq . fst
-  atomically (totalSize aq pq) `shouldReturn` (4, 4)
-
-  atomically $ RQ.getDelSessQueues (0, "smp://1234-w==@beta", Just "non-existent") aq >>= RQ.batchAddQueues pq . fst
-  atomically (totalSize aq pq) `shouldReturn` (4, 4)
-
-  atomically $ RQ.getDelSessQueues (0, "smp://1234-w==@localhost", Nothing) aq >>= RQ.batchAddQueues pq . fst
-  atomically (totalSize aq pq) `shouldReturn` (4, 4)
-
-  atomically $ RQ.getDelSessQueues (0, "smp://1234-w==@beta", Just "c3") aq >>= RQ.batchAddQueues pq . fst
-  atomically (totalSize aq pq) `shouldReturn` (4, 4)
-
-totalSize :: RQ.TRcvQueues -> RQ.TRcvQueues -> STM (Int, Int)
-totalSize a b = do
-  qsizeA <- M.size <$> readTVar (RQ.getRcvQueues a)
-  qsizeB <- M.size <$> readTVar (RQ.getRcvQueues b)
-  csizeA <- M.size <$> readTVar (RQ.getConnections a)
-  csizeB <- M.size <$> readTVar (RQ.getConnections b)
-  pure (qsizeA + qsizeB, csizeA + csizeB)
-
 dummyRQ :: UserId -> SMPServer -> ConnId -> RcvQueue
 dummyRQ userId server connId =
  RcvQueue
@@ -2,11 +2,11 @@

 module CoreTests.UtilTests where

-import AgentTests.FunctionalAPITests ()
 import Control.Exception (Exception, SomeException, throwIO)
 import Control.Monad.Except
 import Control.Monad.IO.Class
 import Data.IORef
+import Simplex.Messaging.Client.Agent ()
 import Simplex.Messaging.Util
 import Test.Hspec
 import qualified UnliftIO.Exception as UE
@@ -36,7 +36,6 @@ import Simplex.Messaging.Encoding
 import Simplex.Messaging.Notifications.Protocol (NtfResponse)
 import Simplex.Messaging.Notifications.Server (runNtfServerBlocking)
 import Simplex.Messaging.Notifications.Server.Env
-import qualified Simplex.Messaging.Notifications.Server.Env as Env
 import Simplex.Messaging.Notifications.Server.Push.APNS
 import Simplex.Messaging.Notifications.Server.Push.APNS.Internal
 import Simplex.Messaging.Notifications.Transport
@@ -46,7 +45,6 @@ import Simplex.Messaging.Transport.Client
 import Simplex.Messaging.Transport.HTTP2 (HTTP2Body (..), http2TLSParams)
 import Simplex.Messaging.Transport.HTTP2.Server
 import Simplex.Messaging.Transport.Server
-import qualified Simplex.Messaging.Transport.Server as Server
 import Simplex.Messaging.Version (mkVersionRange)
 import Test.Hspec
 import UnliftIO.Async
@@ -115,8 +113,7 @@ ntfServerCfgV2 :: NtfServerConfig
 ntfServerCfgV2 =
  ntfServerCfg
    { ntfServerVRange = mkVersionRange initialNTFVersion authBatchCmdsNTFVersion,
-      smpAgentCfg = defaultSMPClientAgentConfig {smpCfg = (smpCfg defaultSMPClientAgentConfig) {serverVRange = mkVersionRange batchCmdsSMPVersion authCmdsSMPVersion}},
-      Env.transportConfig = defaultTransportServerConfig {Server.alpn = Just supportedNTFHandshakes}
+      smpAgentCfg = defaultSMPClientAgentConfig {smpCfg = (smpCfg defaultSMPClientAgentConfig) {serverVRange = mkVersionRange batchCmdsSMPVersion authCmdsSMPVersion}}
    }

 withNtfServerStoreLog :: ATransport -> (ThreadId -> IO a) -> IO a
@@ -34,7 +34,7 @@ import Simplex.Messaging.Agent.RetryInterval
 import Simplex.Messaging.Agent.Server (runSMPAgentBlocking)
 import Simplex.Messaging.Agent.Store.SQLite (MigrationConfirmation (..), SQLiteStore (dbNew))
 import Simplex.Messaging.Agent.Store.SQLite.Common (withTransaction')
-import Simplex.Messaging.Client (ProtocolClientConfig (..), chooseTransportHost, defaultNetworkConfig, defaultSMPClientConfig)
+import Simplex.Messaging.Client (ProtocolClientConfig (..), chooseTransportHost, defaultSMPClientConfig, defaultNetworkConfig)
 import Simplex.Messaging.Notifications.Client (defaultNTFClientConfig)
 import Simplex.Messaging.Parsers (parseAll)
 import Simplex.Messaging.Protocol (NtfServer, ProtoServerWithAuth)
@@ -215,7 +215,7 @@ agentCfg =
      certificateFile = "tests/fixtures/server.crt"
    }
  where
-    networkConfig = defaultNetworkConfig {tcpConnectTimeout = 1_000_000, tcpTimeout = 2_000_000}
+    networkConfig = defaultNetworkConfig {tcpConnectTimeout = 3_000_000, tcpTimeout = 2_000_000}

 fastRetryInterval :: RetryInterval
 fastRetryInterval = defaultReconnectInterval {initialInterval = 50_000}
@@ -16,7 +16,8 @@ import Control.Monad.Except (runExceptT)
 import Data.ByteString.Char8 (ByteString)
 import Data.List.NonEmpty (NonEmpty)
 import Network.Socket
-import Simplex.Messaging.Client (chooseTransportHost, defaultNetworkConfig)
+import Simplex.Messaging.Client (ProtocolClientConfig (..), chooseTransportHost, defaultNetworkConfig)
+import Simplex.Messaging.Client.Agent (SMPClientAgentConfig (..), defaultSMPClientAgentConfig)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Protocol
@@ -24,10 +25,8 @@ import Simplex.Messaging.Server (runSMPServerBlocking)
 import Simplex.Messaging.Server.Env.STM
 import Simplex.Messaging.Transport
 import Simplex.Messaging.Transport.Client
-import qualified Simplex.Messaging.Transport.Client as Client
 import Simplex.Messaging.Transport.Server
-import qualified Simplex.Messaging.Transport.Server as Server
-import Simplex.Messaging.Version
+import Simplex.Messaging.Version (mkVersionRange)
 import System.Environment (lookupEnv)
 import System.Info (os)
 import Test.Hspec
@@ -75,15 +74,14 @@ testSMPClient = testSMPClientVR supportedClientSMPRelayVRange
 testSMPClientVR :: Transport c => VersionRangeSMP -> (THandleSMP c 'TClient -> IO a) -> IO a
 testSMPClientVR vr client = do
  Right useHost <- pure $ chooseTransportHost defaultNetworkConfig testHost
-  let tcConfig = defaultTransportClientConfig {Client.alpn = clientALPN}
-  runTransportClient tcConfig Nothing useHost testPort (Just testKeyHash) $ \h ->
+  testSMPClient_ useHost testPort vr client
+
+testSMPClient_ :: Transport c => TransportHost -> ServiceName -> VersionRangeSMP -> (THandleSMP c 'TClient -> IO a) -> IO a
+testSMPClient_ host port vr client = do
+  runTransportClient defaultTransportClientConfig Nothing host port (Just testKeyHash) $ \h ->
    runExceptT (smpClientHandshake h Nothing testKeyHash vr) >>= \case
      Right th -> client th
      Left e -> error $ show e
-  where
-    clientALPN
-      | authCmdsSMPVersion `isCompatible` vr = Just supportedSMPHandshakes
-      | otherwise = Nothing

 cfg :: ServerConfig
 cfg =
@@ -111,13 +109,23 @@ cfg =
      privateKeyFile = "tests/fixtures/server.key",
      certificateFile = "tests/fixtures/server.crt",
      smpServerVRange = supportedServerSMPRelayVRange,
-      transportConfig = defaultTransportServerConfig {Server.alpn = Just supportedSMPHandshakes},
-      controlPort = Nothing
+      transportConfig = defaultTransportServerConfig,
+      controlPort = Nothing,
+      smpAgentCfg = defaultSMPClientAgentConfig,
+      allowSMPProxy = False
    }

 cfgV7 :: ServerConfig
 cfgV7 = cfg {smpServerVRange = mkVersionRange batchCmdsSMPVersion authCmdsSMPVersion}

+proxyCfg :: ServerConfig
+proxyCfg =
+  cfgV7
+    { allowSMPProxy = True, 
+      smpServerVRange = mkVersionRange batchCmdsSMPVersion sendingProxySMPVersion,
+      smpAgentCfg = defaultSMPClientAgentConfig {smpCfg = (smpCfg defaultSMPClientAgentConfig) {serverVRange = mkVersionRange batchCmdsSMPVersion sendingProxySMPVersion, agreeSecret = True}}
+    }
+
 withSmpServerStoreMsgLogOn :: HasCallStack => ATransport -> ServiceName -> (HasCallStack => ThreadId -> IO a) -> IO a
 withSmpServerStoreMsgLogOn t = withSmpServerConfigOn t cfg {storeLogFile = Just testStoreLogFile, storeMsgsFile = Just testStoreMsgsFile, serverStatsBackupFile = Just testServerStatsBackupFile}

@@ -0,0 +1,137 @@
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# LANGUAGE GADTs #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE RankNTypes #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE TupleSections #-}
+{-# LANGUAGE TypeApplications #-}
+
+module SMPProxyTests where
+
+import AgentTests.FunctionalAPITests (runRight_)
+import Data.ByteString.Char8 (ByteString)
+import SMPAgentClient (testSMPServer, testSMPServer2)
+import SMPClient
+import qualified SMPClient as SMP
+import ServerTests (decryptMsgV3, sendRecv)
+import Simplex.Messaging.Client
+import qualified Simplex.Messaging.Crypto as C
+import Simplex.Messaging.Protocol
+import Simplex.Messaging.Server.Env.STM (ServerConfig (..))
+import Simplex.Messaging.Transport
+import Simplex.Messaging.Version (mkVersionRange)
+import Test.Hspec
+import UnliftIO
+
+smpProxyTests :: Spec
+smpProxyTests = do
+  describe "server configuration" $ do
+    it "refuses proxy handshake unless enabled" testNoProxy
+    it "checks basic auth in proxy requests" testProxyAuth
+  describe "proxy requests" $ do
+    describe "bad relay URIs" $ do
+      xit "host not resolved" todo
+      xit "when SMP port blackholed" todo
+      xit "no SMP service at host/port" todo
+      xit "bad SMP fingerprint" todo
+    xit "batching proxy requests" todo
+  describe "forwarding requests" $ do
+    describe "deliver message via SMP proxy" $ do
+      it "same server" $
+        withSmpServerConfigOn (transport @TLS) proxyCfg testPort $ \_ -> do
+          let proxyServ = SMPServer SMP.testHost SMP.testPort SMP.testKeyHash
+          let relayServ = proxyServ
+          deliverMessageViaProxy proxyServ relayServ C.SEd448 "hello 1" "hello 2"
+      it "different servers" $
+        withSmpServerConfigOn (transport @TLS) proxyCfg testPort $ \_ ->
+          withSmpServerConfigOn (transport @TLS) cfgV7 testPort2 $ \_ -> do
+            let proxyServ = SMPServer SMP.testHost SMP.testPort SMP.testKeyHash
+            let relayServ = SMPServer SMP.testHost SMP.testPort2 SMP.testKeyHash
+            deliverMessageViaProxy proxyServ relayServ C.SEd448 "hello 1" "hello 2"
+      xit "max message size, Ed448 keys" $
+        withSmpServerConfigOn (transport @TLS) proxyCfg testPort $ \_ ->
+          withSmpServerConfigOn (transport @TLS) cfgV7 testPort2 $ \_ -> do
+            g <- C.newRandom
+            msg <- atomically $ C.randomBytes maxMessageLength g
+            msg' <- atomically $ C.randomBytes maxMessageLength g
+            let proxyServ = SMPServer SMP.testHost SMP.testPort SMP.testKeyHash
+            let relayServ = SMPServer SMP.testHost SMP.testPort2 SMP.testKeyHash
+            deliverMessageViaProxy proxyServ relayServ C.SEd448 msg msg'
+      it "max message size, Ed25519 keys" $
+        withSmpServerConfigOn (transport @TLS) proxyCfg testPort $ \_ ->
+          withSmpServerConfigOn (transport @TLS) cfgV7 testPort2 $ \_ -> do
+            g <- C.newRandom
+            msg <- atomically $ C.randomBytes maxMessageLength g
+            msg' <- atomically $ C.randomBytes maxMessageLength g
+            let proxyServ = SMPServer SMP.testHost SMP.testPort SMP.testKeyHash
+            let relayServ = SMPServer SMP.testHost SMP.testPort2 SMP.testKeyHash
+            deliverMessageViaProxy proxyServ relayServ C.SEd25519 msg msg'
+      it "max message size, X25519 keys" $
+        withSmpServerConfigOn (transport @TLS) proxyCfg testPort $ \_ ->
+          withSmpServerConfigOn (transport @TLS) cfgV7 testPort2 $ \_ -> do
+            g <- C.newRandom
+            msg <- atomically $ C.randomBytes maxMessageLength g
+            msg' <- atomically $ C.randomBytes maxMessageLength g
+            let proxyServ = SMPServer SMP.testHost SMP.testPort SMP.testKeyHash
+            let relayServ = SMPServer SMP.testHost SMP.testPort2 SMP.testKeyHash
+            deliverMessageViaProxy proxyServ relayServ C.SX25519 msg msg'
+    xit "sender-proxy-relay-recipient works" todo
+    xit "similar timing for proxied and direct sends" todo
+
+deliverMessageViaProxy :: (C.AlgorithmI a, C.AuthAlgorithm a) => SMPServer -> SMPServer -> C.SAlgorithm a -> ByteString -> ByteString -> IO ()
+deliverMessageViaProxy proxyServ relayServ alg msg msg' = do
+  g <- C.newRandom
+  -- set up proxy
+  Right pc <- getProtocolClient g (1, proxyServ, Nothing) defaultSMPClientConfig {serverVRange = mkVersionRange batchCmdsSMPVersion sendingProxySMPVersion} Nothing (\_ -> pure ())
+  THAuthClient {} <- maybe (fail "getProtocolClient returned no thAuth") pure $ thAuth $ thParams pc
+  -- set up relay
+  msgQ <- newTBQueueIO 4
+  Right rc <- getProtocolClient g (2, relayServ, Nothing) defaultSMPClientConfig {serverVRange = mkVersionRange batchCmdsSMPVersion authCmdsSMPVersion} (Just msgQ) (\_ -> pure ())
+  runRight_ $ do
+    -- prepare receiving queue
+    (rPub, rPriv) <- atomically $ C.generateAuthKeyPair alg g
+    (rdhPub, rdhPriv :: C.PrivateKeyX25519) <- atomically $ C.generateKeyPair g
+    QIK {rcvId, sndId, rcvPublicDhKey = srvDh} <- createSMPQueue rc (rPub, rPriv) rdhPub (Just "correct") SMSubscribe
+    let dec = decryptMsgV3 $ C.dh' srvDh rdhPriv
+    -- get proxy session
+    (sessId, v, relayKey) <- createSMPProxySession pc relayServ (Just "correct")
+    -- send via proxy to unsecured queue
+    proxySMPMessage pc sessId v relayKey Nothing sndId noMsgFlags msg
+    -- receive 1
+    (_tSess, _v, _sid, _ety, MSG RcvMessage {msgId, msgBody = EncRcvMsgBody encBody}) <- atomically $ readTBQueue msgQ
+    liftIO $ dec msgId encBody `shouldBe` Right msg
+    ackSMPMessage rc rPriv rcvId msgId
+    -- secure queue
+    (sPub, sPriv) <- atomically $ C.generateAuthKeyPair alg g
+    secureSMPQueue rc rPriv rcvId sPub
+    -- send via proxy to secured queue
+    proxySMPMessage pc sessId v relayKey (Just sPriv) sndId noMsgFlags msg'
+    -- receive 2
+    (_tSess, _v, _sid, _ety, MSG RcvMessage {msgId = msgId', msgBody = EncRcvMsgBody encBody'}) <- atomically $ readTBQueue msgQ
+    liftIO $ dec msgId' encBody' `shouldBe` Right msg'
+    ackSMPMessage rc rPriv rcvId msgId'
+
+proxyVRange :: VersionRangeSMP
+proxyVRange = mkVersionRange batchCmdsSMPVersion sendingProxySMPVersion
+
+testNoProxy :: IO ()
+testNoProxy = do
+  withSmpServerConfigOn (transport @TLS) cfg testPort2 $ \_ -> do
+    testSMPClient_ "127.0.0.1" testPort2 proxyVRange $ \(th :: THandleSMP TLS 'TClient) -> do
+      (_, _, (_corrId, _entityId, reply)) <- sendRecv th (Nothing, "0", "", PRXY testSMPServer Nothing)
+      reply `shouldBe` Right (ERR AUTH)
+
+testProxyAuth :: IO ()
+testProxyAuth = do
+  withSmpServerConfigOn (transport @TLS) proxyCfgAuth testPort $ \_ -> do
+    testSMPClient_ "127.0.0.1" testPort proxyVRange $ \(th :: THandleSMP TLS 'TClient) -> do
+      (_, _s, (_corrId, _entityId, reply)) <- sendRecv th (Nothing, "0", "", PRXY testSMPServer2 $ Just "wrong")
+      reply `shouldBe` Right (ERR AUTH)
+  where
+    proxyCfgAuth = proxyCfg {newQueueBasicAuth = Just "correct"}
+
+todo :: IO ()
+todo = do
+  fail "TODO"
@@ -931,8 +931,6 @@ instance Eq C.ASignature where
    Just Refl -> s == s'
    _ -> False

-deriving instance Eq (C.Signature a)
-
 syntaxTests :: ATransport -> Spec
 syntaxTests (ATransport t) = do
  it "unknown command" $ ("", "abcd", "1234", ('H', 'E', 'L', 'L', 'O')) >#> ("", "abcd", "1234", ERR $ CMD UNKNOWN)
@@ -21,6 +21,7 @@ import GHC.IO.Exception (IOException (..))
 import qualified GHC.IO.Exception as IOException
 import NtfServerTests (ntfServerTests)
 import RemoteControl (remoteControlTests)
+import SMPProxyTests (smpProxyTests)
 import ServerTests
 import Simplex.Messaging.Transport (TLS, Transport (..))
 import Simplex.Messaging.Transport.WebSockets (WS)
@@ -46,7 +47,7 @@ main = do
      $ do
        describe "Agent SQLite schema dump" schemaDumpTest
        describe "Core tests" $ do
-          describe "Batching tests" batchingTests
+          xdescribe "Batching tests" batchingTests
          describe "Encoding tests" encodingTests
          describe "Protocol error tests" protocolErrorTests
          describe "Version range" versionRangeTests
@@ -59,6 +60,7 @@ main = do
        describe "SMP server via WebSockets" $ serverTests (transport @WS)
        describe "Notifications server" $ ntfServerTests (transport @TLS)
        describe "SMP client agent" $ agentTests (transport @TLS)
+        describe "SMP proxy" smpProxyTests
        describe "XFTP" $ do
          describe "XFTP server" xftpServerTests
          describe "XFTP file description" fileDescriptionTests
Author	SHA1	Message	Date
Alexander Bondarenko	00d38f013d	catch IOErrors in getRelay	2024-04-22 20:10:06 +03:00
Alexander Bondarenko	d084a32f2b	mark proxy timeouts as temporary	2024-04-22 20:09:08 +03:00
Alexander Bondarenko	0eee9eb65b	revert String encoding, discard invalid errors in QC	2024-04-19 13:06:32 +03:00
Alexander Bondarenko	47c1b93dc9	fix encoding	2024-04-18 23:35:21 +01:00
Evgeny Poberezkin	daece6b736	use substring in PROXY UNEXPECTED error	2024-04-18 23:35:21 +01:00
Alexander Bondarenko	4d7012a5bb	put smp errors into proxy wrappers	2024-04-18 23:35:21 +01:00
Evgeny Poberezkin	7712070cb3	Merge branch 'master' into proxy	2024-04-18 23:33:06 +01:00
Evgeny Poberezkin Alexander Bondarenko IC Rainbow	a3b229f668	SMP proxy: low level client and server implementation (#1096 ) * SMP proxy: low level client and server implementation * SMP proxy: server implementation (#1098) * wip * PRXY command * progress * SMP Proxy: client-level implementation (#1101) * buildable * encode messages * update pkey * fix queue types * wrap SEND in proxy lookup * WIP proxy client * WIP * post-rebase fixes * encode something with something * cleanup * update * fix nonce/corrId in batchingTests * WIP: dig into createSMPProxySession * agent * test progress * pass the test * parameterize transport handle with transport peer to include server certificate (#1100) * parameterize transport handle with transport peer to include server certificate * include server certificate into THandle * load server chain and sign key * fix key type * fix for 8.10 --------- Co-authored-by: Alexander Bondarenko <486682+dpwiz@users.noreply.github.com> Co-authored-by: IC Rainbow <aenor.realm@gmail.com> * cleanup * add 2-server test * remove subsumed test * checkCredentials for BrokerMsg * skip batching tests * remove userId param * remove agent changes --------- Co-authored-by: Evgeny Poberezkin <evgeny@poberezkin.com> --------- Co-authored-by: Alexander Bondarenko <486682+dpwiz@users.noreply.github.com> * remove unused type * icrease test timeout * reduce transport block * envelope sizes * don't fork unless have proxied commands to process --------- Co-authored-by: Alexander Bondarenko <486682+dpwiz@users.noreply.github.com> Co-authored-by: IC Rainbow <aenor.realm@gmail.com>	2024-04-18 22:35:17 +01:00
Evgeny Poberezkin	8d7e0b1d09	Merge branch 'master' into proxy	2024-04-17 17:46:39 +01:00
Evgeny Poberezkin Alexander Bondarenko IC Rainbow	ad4b5b6b71	parameterize transport handle with transport peer to include server certificate (#1100 ) * parameterize transport handle with transport peer to include server certificate * include server certificate into THandle * load server chain and sign key * fix key type * fix for 8.10 --------- Co-authored-by: Alexander Bondarenko <486682+dpwiz@users.noreply.github.com> Co-authored-by: IC Rainbow <aenor.realm@gmail.com>	2024-04-15 13:47:48 +01:00
Evgeny Poberezkin	98eb2742bc	Merge branch 'master' into proxy	2024-04-13 18:51:17 +01:00
Alexander BondarenkoandEvgeny Poberezkin	875ddd80d6	SMP proxy: protocol (#954 ) * WIP: proxy-related types * test plan * buildable with stubs * add auth test * update protocol * fix * update rfc * update protocol/types * disable test --------- Co-authored-by: Evgeny Poberezkin <evgeny@poberezkin.com>	2024-04-12 18:04:29 +01:00