catch IOErrors in getRelay

* remove (or make optional) client key from handshakes

* remove comment

.github/workflows/build.yml

@@ -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
 

CHANGELOG.md

@@ -1,3 +1,22 @@
+# 5.6.2
+
+Version 5.6.2.2.
+
+SMP agent:
+- Lower memory consumption (~20-25%).
+- More stable XFTP file uploads and downloads.
+- API to receive network connectivity changes from the apps.
+- to reduce battery consumption: connection attempts interval growing to every 2 hours when app reports as offline.
+- to reduce retries and traffic: 50% increased timeouts when on mobile network.
+
+XFTP server:
+- expire files on start.
+- version negotiation based on TLS ALPN and handshake.
+
+NTF server:
+- reduced downtime by ~100x faster start time.
+- exclude test tokens from statistics.
+
 # 5.6.1
 
 Version 5.6.1.0.

cabal.project

@@ -14,12 +14,6 @@ source-repository-package
     location: https://github.com/simplex-chat/aeson.git
     tag: aab7b5a14d6c5ea64c64dcaee418de1bb00dcc2b
 
--- old bs/text compat for 8.10
-source-repository-package
-    type: git
-    location: https://github.com/simplex-chat/base64.git
-    tag: 2d77b6dbcaffc00570a70be8694049f3710e7c94
-
 source-repository-package
     type: git
     location: https://github.com/simplex-chat/hs-socks.git

notes-flow.txt

@@ -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

package.yaml

@@ -1,5 +1,5 @@
 name: simplexmq
-version: 5.6.2.0
+version: 5.6.2.2
 synopsis: SimpleXMQ message broker
 description: |
   This package includes <./docs/Simplex-Messaging-Server.html server>,
@@ -31,7 +31,7 @@ dependencies:
   - async == 2.2.*
   - attoparsec == 0.14.*
   - base >= 4.14 && < 5
-  - base64 == 1.0.*
+  - base64-bytestring >= 1.0 && < 1.3
   - case-insensitive == 1.2.*
   - composition == 1.0.*
   - constraints >= 0.12 && < 0.14
@@ -169,6 +169,11 @@ tests:
       - silently == 1.2.*
       - main-tester == 0.2.*
       - timeit == 2.0.*
+    ghc-options:
+      - -threaded
+      - -rtsopts
+      - -with-rtsopts=-A64M
+      - -with-rtsopts=-N1
 
 ghc-options:
   # - -haddock

rfcs/2023-09-12-second-relays.md

@@ -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).
 

rfcs/2024-03-28-xftp-version.md

@@ -0,0 +1,120 @@
+# XFTP version agreement
+
+## Problem
+
+XFTP is using HTTP2 protocol for encoding requests and responses.
+Unlike SMP which has a connection handshake initiated by a server and signals available versions XFTP/HTTP2 is almost entirely client-driven.
+So, a client can only try to guess which protocol versions are supported by a server by sending a probe/hello request first.
+Determining the endpoint for such a request is an implicit version agreement by itself.
+Sending such a request to an old server would error out and requiring it from old clients would break them.
+
+## Solution
+
+The TLS layer used by the XFTP server has an optional [ALPN](https://datatracker.ietf.org/doc/html/rfc7301) extension which allows the client and server to negotiate protocols and store the decision in TLS session context.
+Unless a client and a server run ALPN-aware versions, they would default to the old "unversioned" protocol.
+
+TLS extension content is a 65kb chunk, but ALPN standard breaks it into 254b-sized chunks making it unusable for things like key exchange.
+The exchange is still client-driven: the client proposes a list, and then a server callback picks one.
+In effect, this makes it usable only to signal that some application-level handshake is desired and supported.
+
+## Implementation
+
+ALPN can be used to negotiate for any TLS-based protocol, but the description will focus on XFTP.
+
+TransportClientConfig gets a new `alpn :: Maybe [ALPN]` field so a TLS transport can use it during TLS client creation.
+XFTP client sets it to `Just ["xftp/1"]`.
+The exact value is not important as long it is in agreement with the server side, but ALPN RFC insists on it being an IANA-registered identifier.
+
+XFTP server sets `onALPNClientSuggest` TLS hook to pick the protocol when it is provided.
+The `tls` library treats SHOULD from the RFC as MUST and does a client-side check that the server responded with one of the client-proposed protocols.
+
+Upon connection, transport implementation invokes `getNegotiatedProtocol` and stores it in `tlsALPN :: Maybe ALPN` field of transport context.
+HTTP2 transport implementation using `withHTTP2` passes negotiated "protocol" to client and server setup callbacks where they store it in their respective wrappers along with TLS session ID.
+A server request handler then knows by looking at the `sessionALPN` if it should require a "handshake" request first.
+A client code that got HTTP2Client with `sessionALPN` set knows if it has to proceed with handshake request.
+A handshake request still has to be initiated by a client, so it should be kept minimal, just enough data to pass the initiative to a server.
+A reply to that initial request should contain a server version range for the client to pick.
+A client then commits to a version, sending its part of a handshake.
+
+In the future ALPN negotiation can be dropped in favor of mandatory handshakes or used to signal further handshake schemes.
+
+The XFTP handshake data types and validation code are cloned from SMP.
+Currently they carry version information and session authentication parameters.
+Authentication parameters made mandatory as this exchange is guarded by the handshake version.
+
+### Server side
+
+`runHTTP2Server` callback used by `xftpServer` should get access to the session state to track handshakes.
+A local `TMap SessionId Handshake` is enough to switch request handlers.
+The HTTP2 server framework is extended with a way to signal client disconnection to remove sessions from this map.
+
+The `Handshake` type mimics implicit state in stream based handshakes of SMP and NTF.
+
+```haskell
+data Handshake
+  = HandshakeSent C.PrivateKeyX25519 -- server private key that will be merged with client public in `THandleAuth`
+  | HandshakeAccepted THandleAuth VersionXFTP -- session steady state after handshakes
+```
+
+An HTTP2 request without ALPN is treated as legacy and requires no session entry.
+Its `Request`s are marked with `THandleParams {thVersion = VersionXFTP 1, ..}`.
+
+An HTTP2 request with ALPN requires a session lookup.
+- A lack of entry indicates that a client must send an empty request, to which the server replies with its "server handshake" block and stores its private state in `HandshakeSent`.
+- If the session entry contains `HandshakeSent`, then the only valid request content is the "client handshake" block.
+  The server validates client handshake (in the same way as SMP) and stores authentication and version in `HandshakeAccepted`
+- If the session entry contains `HandshakeAccepted`, then the server just passes it to `THandleParams`.
+
+### Client side
+
+`getXFTPClient` tweaks its transport config to include the ALPN marker and then checks if the client got its `sessionALPN` value.
+If there's a value set, it then sends an initial block and checks out the server handshake in response.
+After validation, it sends "client handshake" request to finish version negotiation.
+
+```haskell
+let tcConfig = (transportClientConfig xftpNetworkConfig) {alpn = Just ["xftp/1"]}
+-- ...
+http2Client <- liftEitherError xftpClientError $ getVerifiedHTTP2Client -- ...
+thVersion <- case sessionALPN http2Client of
+  Nothing -> pure $ VersionXFTP 1
+  Just proto -> negotiate http2Client proto
+```
+
+The resulting `XFTPClient` then contains a negotiated version and can be used to send transmissions with a more recent encoding.
+
+## Block encoding
+
+### Client Hello (request)
+
+A request with an empty body and no padding.
+
+### Server handshake (response)
+
+SMP-encoded and padded to `xftpBlockSize` (~16kb).
+
+```haskell
+data XFTPServerHandshake = XFTPServerHandshake
+  { xftpVersionRange :: VersionRangeXFTP,
+    sessionId :: SessionId, -- validated by client against TLS unique
+    authPubKey ::
+      ( X.CertificateChain, -- fingerprint validated by client against pre-shared hash
+        X.SignedExact X.PubKey -- signature validated by client against server key from TLS
+      )
+  }
+```
+
+### Client handshake (request)
+
+SMP-encoded and padded to `xftpBlockSize` (~16kb).
+
+```haskell
+data XFTPClientHandshake = XFTPClientHandshake
+  { xftpVersion :: VersionXFTP,
+    keyHash :: C.KeyHash, -- validated by server against its own cert fingerprint
+    authPubKey :: C.PublicKeyX25519
+  }
+```
+
+### Server confirmation (response)
+
+A response with an empty body and no padding.

simplexmq.cabal

@@ -5,7 +5,7 @@ cabal-version: 1.12
 -- see: https://github.com/sol/hpack
 
 name:           simplexmq
-version:        5.6.2.0
+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
@@ -119,8 +119,6 @@ library
       Simplex.Messaging.Crypto.SNTRUP761.Bindings.FFI
       Simplex.Messaging.Crypto.SNTRUP761.Bindings.RNG
       Simplex.Messaging.Encoding
-      Simplex.Messaging.Encoding.Base64
-      Simplex.Messaging.Encoding.Base64.URL
       Simplex.Messaging.Encoding.String
       Simplex.Messaging.Notifications.Client
       Simplex.Messaging.Notifications.Protocol
@@ -149,6 +147,7 @@ library
       Simplex.Messaging.Server.Stats
       Simplex.Messaging.Server.StoreLog
       Simplex.Messaging.ServiceScheme
+      Simplex.Messaging.Session
       Simplex.Messaging.TMap
       Simplex.Messaging.Transport
       Simplex.Messaging.Transport.Buffer
@@ -191,7 +190,7 @@ library
     , async ==2.2.*
     , attoparsec ==0.14.*
     , base >=4.14 && <5
-    , base64 ==1.0.*
+    , base64-bytestring >=1.0 && <1.3
     , case-insensitive ==1.2.*
     , composition ==1.0.*
     , constraints >=0.12 && <0.14
@@ -265,7 +264,7 @@ executable ntf-server
     , async ==2.2.*
     , attoparsec ==0.14.*
     , base >=4.14 && <5
-    , base64 ==1.0.*
+    , base64-bytestring >=1.0 && <1.3
     , case-insensitive ==1.2.*
     , composition ==1.0.*
     , constraints >=0.12 && <0.14
@@ -340,7 +339,7 @@ executable smp-agent
     , async ==2.2.*
     , attoparsec ==0.14.*
     , base >=4.14 && <5
-    , base64 ==1.0.*
+    , base64-bytestring >=1.0 && <1.3
     , case-insensitive ==1.2.*
     , composition ==1.0.*
     , constraints >=0.12 && <0.14
@@ -415,7 +414,7 @@ executable smp-server
     , async ==2.2.*
     , attoparsec ==0.14.*
     , base >=4.14 && <5
-    , base64 ==1.0.*
+    , base64-bytestring >=1.0 && <1.3
     , case-insensitive ==1.2.*
     , composition ==1.0.*
     , constraints >=0.12 && <0.14
@@ -490,7 +489,7 @@ executable xftp
     , async ==2.2.*
     , attoparsec ==0.14.*
     , base >=4.14 && <5
-    , base64 ==1.0.*
+    , base64-bytestring >=1.0 && <1.3
     , case-insensitive ==1.2.*
     , composition ==1.0.*
     , constraints >=0.12 && <0.14
@@ -565,7 +564,7 @@ executable xftp-server
     , async ==2.2.*
     , attoparsec ==0.14.*
     , base >=4.14 && <5
-    , base64 ==1.0.*
+    , base64-bytestring >=1.0 && <1.3
     , case-insensitive ==1.2.*
     , composition ==1.0.*
     , constraints >=0.12 && <0.14
@@ -653,6 +652,7 @@ test-suite simplexmq-test
       ServerTests
       SMPAgentClient
       SMPClient
+      SMPProxyTests
       Util
       XFTPAgent
       XFTPCLI
@@ -663,7 +663,7 @@ test-suite simplexmq-test
       tests
   default-extensions:
       StrictData
-  ghc-options: -Wall -Wcompat -Werror=incomplete-patterns -Wredundant-constraints -Wincomplete-record-updates -Wincomplete-uni-patterns -Wunused-type-patterns -O2
+  ghc-options: -Wall -Wcompat -Werror=incomplete-patterns -Wredundant-constraints -Wincomplete-record-updates -Wincomplete-uni-patterns -Wunused-type-patterns -O2 -threaded -rtsopts -with-rtsopts=-A64M -with-rtsopts=-N1
   build-depends:
       HUnit ==1.6.*
     , QuickCheck ==2.14.*
@@ -674,7 +674,7 @@ test-suite simplexmq-test
     , async ==2.2.*
     , attoparsec ==0.14.*
     , base >=4.14 && <5
-    , base64 ==1.0.*
+    , base64-bytestring >=1.0 && <1.3
     , case-insensitive ==1.2.*
     , composition ==1.0.*
     , constraints >=0.12 && <0.14

src/Simplex/FileTransfer/Agent.hs

@@ -179,7 +179,8 @@ runXFTPRcvWorker c srv Worker {doWork} = do
         RcvFileChunk {rcvFileId, rcvFileEntityId, fileTmpPath, replicas = []} -> rcvWorkerInternalError c rcvFileId rcvFileEntityId (Just fileTmpPath) "chunk has no replicas"
         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 ->
+          withRetryIntervalLimit xftpConsecutiveRetries ri' $ \delay' loop -> do
+            lift $ waitForUserNetwork c
             downloadFileChunk fc replica
               `catchAgentError` \e -> retryOnError "XFTP rcv worker" (retryLoop loop e delay') (retryDone e) e
           where
@@ -422,7 +423,8 @@ runXFTPSndPrepareWorker c Worker {doWork} = do
           where
             tryCreate = do
               usedSrvs <- newTVarIO ([] :: [XFTPServer])
-              withRetryInterval (riFast ri) $ \_ loop ->
+              withRetryInterval (riFast ri) $ \_ loop -> do
+                lift $ waitForUserNetwork c
                 createWithNextSrv usedSrvs
                   `catchAgentError` \e -> retryOnError "XFTP prepare worker" (retryLoop loop) (throwError e) e
               where
@@ -454,7 +456,8 @@ runXFTPSndWorker c srv Worker {doWork} = do
         SndFileChunk {sndFileId, sndFileEntityId, filePrefixPath, replicas = []} -> sndWorkerInternalError c sndFileId sndFileEntityId (Just filePrefixPath) "chunk has no replicas"
         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 ->
+          withRetryIntervalLimit xftpConsecutiveRetries ri' $ \delay' loop -> do
+            lift $ waitForUserNetwork c
             uploadFileChunk cfg fc replica
               `catchAgentError` \e -> retryOnError "XFTP snd worker" (retryLoop loop e delay') (retryDone e) e
           where
@@ -620,7 +623,8 @@ runXFTPDelWorker c srv Worker {doWork} = do
       where
         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 ->
+          withRetryIntervalLimit xftpConsecutiveRetries ri' $ \delay' loop -> do
+            lift $ waitForUserNetwork c
             deleteChunkReplica
               `catchAgentError` \e -> retryOnError "XFTP del worker" (retryLoop loop e delay') (retryDone e) e
           where

src/Simplex/FileTransfer/Client.hs

@@ -4,11 +4,14 @@
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
 {-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE TupleSections #-}
 {-# LANGUAGE TypeApplications #-}
 
 module Simplex.FileTransfer.Client where
 
+import Control.Logger.Simple
 import Control.Monad
 import Control.Monad.Except
 import Crypto.Random (ChaChaDRG)
@@ -20,10 +23,12 @@ import Data.Int (Int64)
 import Data.List.NonEmpty (NonEmpty (..))
 import Data.Time (UTCTime)
 import Data.Word (Word32)
+import qualified Data.X509 as X
+import qualified Data.X509.Validation as XV
 import qualified Network.HTTP.Types as N
 import qualified Network.HTTP2.Client as H
-import Simplex.FileTransfer.Description (mb)
 import Simplex.FileTransfer.Protocol
+import Simplex.FileTransfer.Server.Env (supportedXFTPhandshakes)
 import Simplex.FileTransfer.Transport
 import Simplex.Messaging.Client
   ( NetworkConfig (..),
@@ -37,6 +42,7 @@ import Simplex.Messaging.Client
 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)
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol
   ( BasicAuth,
@@ -45,25 +51,27 @@ import Simplex.Messaging.Protocol
     RecipientId,
     SenderId,
   )
-import Simplex.Messaging.Transport (THandleParams (..), supportedParameters)
-import Simplex.Messaging.Transport.Client (TransportClientConfig, TransportHost)
+import Simplex.Messaging.Transport (ALPN, HandshakeError (VERSION), THandleAuth (..), THandleParams (..), TransportError (..), TransportPeer (..), supportedParameters)
+import Simplex.Messaging.Transport.Client (TransportClientConfig, TransportHost, alpn)
 import Simplex.Messaging.Transport.HTTP2
 import Simplex.Messaging.Transport.HTTP2.Client
 import Simplex.Messaging.Transport.HTTP2.File
-import Simplex.Messaging.Util (bshow, whenM)
+import Simplex.Messaging.Util (bshow, liftEitherWith, liftError', tshow, whenM)
+import Simplex.Messaging.Version (compatibleVersion, pattern Compatible)
 import UnliftIO
 import UnliftIO.Directory
 
 data XFTPClient = XFTPClient
   { http2Client :: HTTP2Client,
     transportSession :: TransportSession FileResponse,
-    thParams :: THandleParams XFTPVersion,
+    thParams :: THandleParams XFTPVersion 'TClient,
     config :: XFTPClientConfig
   }
 
 data XFTPClientConfig = XFTPClientConfig
   { xftpNetworkConfig :: NetworkConfig,
-    uploadTimeoutPerMb :: Int64
+    serverVRange :: VersionRangeXFTP,
+    clientALPN :: Maybe [ALPN]
   }
 
 data XFTPChunkBody = XFTPChunkBody
@@ -85,12 +93,13 @@ defaultXFTPClientConfig :: XFTPClientConfig
 defaultXFTPClientConfig =
   XFTPClientConfig
     { xftpNetworkConfig = defaultNetworkConfig,
-      uploadTimeoutPerMb = 10000000 -- 10 seconds
+      serverVRange = supportedFileServerVRange,
+      clientALPN = Just supportedXFTPhandshakes
     }
 
 getXFTPClient :: TransportSession FileResponse -> XFTPClientConfig -> (XFTPClient -> IO ()) -> IO (Either XFTPClientError XFTPClient)
-getXFTPClient transportSession@(_, srv, _) config@XFTPClientConfig {xftpNetworkConfig} disconnected = runExceptT $ do
-  let tcConfig = transportClientConfig xftpNetworkConfig
+getXFTPClient transportSession@(_, srv, _) config@XFTPClientConfig {clientALPN, xftpNetworkConfig, serverVRange} disconnected = runExceptT $ do
+  let tcConfig = (transportClientConfig xftpNetworkConfig) {alpn = clientALPN}
       http2Config = xftpHTTP2Config tcConfig config
       username = proxyUsername transportSession
       ProtocolServer _ host port keyHash = srv
@@ -98,13 +107,53 @@ getXFTPClient transportSession@(_, srv, _) config@XFTPClientConfig {xftpNetworkC
   clientVar <- newTVarIO Nothing
   let usePort = if null port then "443" else port
       clientDisconnected = readTVarIO clientVar >>= mapM_ disconnected
-  http2Client <- withExceptT xftpClientError . ExceptT $ getVerifiedHTTP2Client (Just username) useHost usePort (Just keyHash) Nothing http2Config clientDisconnected
-  let HTTP2Client {sessionId} = http2Client
-      thParams = THandleParams {sessionId, blockSize = xftpBlockSize, thVersion = currentXFTPVersion, thAuth = Nothing, implySessId = False, batch = True}
-      c = XFTPClient {http2Client, thParams, transportSession, config}
+  http2Client <- liftError' xftpClientError $ getVerifiedHTTP2Client (Just username) useHost usePort (Just keyHash) Nothing http2Config clientDisconnected
+  let HTTP2Client {sessionId, sessionALPN} = http2Client
+      thParams0 = THandleParams {sessionId, blockSize = xftpBlockSize, thVersion = VersionXFTP 1, thAuth = Nothing, implySessId = False, batch = True}
+  logDebug $ "Client negotiated handshake protocol: " <> tshow sessionALPN
+  thParams@THandleParams {thVersion} <- case sessionALPN of
+    Just "xftp/1" -> xftpClientHandshakeV1 serverVRange keyHash http2Client thParams0
+    Nothing -> pure thParams0
+    _ -> throwError $ PCETransportError (TEHandshake VERSION)
+  logDebug $ "Client negotiated protocol: " <> tshow thVersion
+  let c = XFTPClient {http2Client, thParams, transportSession, config}
   atomically $ writeTVar clientVar $ Just c
   pure c
 
+xftpClientHandshakeV1 :: VersionRangeXFTP -> C.KeyHash -> HTTP2Client -> THandleParamsXFTP 'TClient -> ExceptT XFTPClientError IO (THandleParamsXFTP 'TClient)
+xftpClientHandshakeV1 serverVRange keyHash@(C.KeyHash kh) c@HTTP2Client {sessionId, serverKey} thParams0 = do
+  shs@XFTPServerHandshake {authPubKey = ck} <- getServerHandshake
+  (v, sk) <- processServerHandshake shs
+  sendClientHandshake XFTPClientHandshake {xftpVersion = v, keyHash}
+  pure thParams0 {thAuth = Just THAuthClient {serverPeerPubKey = sk, serverCertKey = ck, sessSecret = Nothing}, thVersion = v}
+  where
+    getServerHandshake :: ExceptT XFTPClientError IO XFTPServerHandshake
+    getServerHandshake = do
+      let helloReq = H.requestNoBody "POST" "/" []
+      HTTP2Response {respBody = HTTP2Body {bodyHead = shsBody}} <-
+        liftError' (const $ PCEResponseError HANDSHAKE) $ sendRequest c helloReq Nothing
+      liftHS . smpDecode =<< liftHS (C.unPad shsBody)
+    processServerHandshake :: XFTPServerHandshake -> ExceptT XFTPClientError IO (VersionXFTP, C.PublicKeyX25519)
+    processServerHandshake XFTPServerHandshake {xftpVersionRange, sessionId = serverSessId, authPubKey = serverAuth} = do
+      unless (sessionId == serverSessId) $ throwError $ PCEResponseError SESSION
+      case xftpVersionRange `compatibleVersion` serverVRange of
+        Nothing -> throwError $ PCEResponseError HANDSHAKE
+        Just (Compatible v) ->
+          fmap (v,) . liftHS $ do
+            let (X.CertificateChain cert, exact) = serverAuth
+            case cert of
+              [_leaf, ca] | XV.Fingerprint kh == XV.getFingerprint ca X.HashSHA256 -> pure ()
+              _ -> throwError "bad certificate"
+            pubKey <- maybe (throwError "bad server key type") (`C.verifyX509` exact) serverKey
+            C.x509ToPublic (pubKey, []) >>= C.pubKey
+    sendClientHandshake :: XFTPClientHandshake -> ExceptT XFTPClientError IO ()
+    sendClientHandshake chs = do
+      chs' <- liftHS $ C.pad (smpEncode chs) xftpBlockSize
+      let chsReq = H.requestBuilder "POST" "/" [] $ byteString chs'
+      HTTP2Response {respBody = HTTP2Body {bodyHead}} <- liftError' (const $ PCEResponseError HANDSHAKE) $ sendRequest c chsReq Nothing
+      unless (B.null bodyHead) $ throwError $ PCEResponseError HANDSHAKE
+    liftHS = liftEitherWith (const $ PCEResponseError HANDSHAKE)
+
 closeXFTPClient :: XFTPClient -> IO ()
 closeXFTPClient XFTPClient {http2Client} = closeHTTP2Client http2Client
 
@@ -136,16 +185,18 @@ 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)
 sendXFTPTransmission XFTPClient {config, thParams, http2Client} t chunkSpec_ = do
   let req = H.requestStreaming N.methodPost "/" [] streamBody
-      reqTimeout = (\XFTPChunkSpec {chunkSize} -> chunkTimeout config chunkSize) <$> chunkSpec_
-  HTTP2Response {respBody = body@HTTP2Body {bodyHead}} <- withExceptT xftpClientError . ExceptT $ sendRequest http2Client req reqTimeout
+      reqTimeout = xftpReqTimeout config $ (\XFTPChunkSpec {chunkSize} -> chunkSize) <$> chunkSpec_
+  HTTP2Response {respBody = body@HTTP2Body {bodyHead}} <- withExceptT xftpClientError . ExceptT $ sendRequest http2Client req (Just reqTimeout)
   when (B.length bodyHead /= xftpBlockSize) $ throwError $ PCEResponseError BLOCK
   -- TODO validate that the file ID is the same as in the request?
   (_, _, (_, _fId, respOrErr)) <- liftEither . first PCEResponseError $ xftpDecodeTransmission thParams bodyHead
@@ -198,15 +249,20 @@ downloadXFTPChunk g c@XFTPClient {config} rpKey fId chunkSpec@XFTPRcvChunkSpec {
         let t = chunkTimeout config chunkSize
         ExceptT (sequence <$> (t `timeout` download cbState)) >>= maybe (throwError PCEResponseTimeout) pure
         where
-          download cbState = runExceptT $
-            withExceptT PCEResponseError $
+          download cbState =
+            runExceptT . withExceptT PCEResponseError $
               receiveEncFile chunkPart cbState chunkSpec `catchError` \e ->
                 whenM (doesFileExist filePath) (removeFile filePath) >> throwError e
       _ -> throwError $ PCEResponseError NO_FILE
     (r, _) -> throwError . PCEUnexpectedResponse $ bshow r
 
+xftpReqTimeout :: XFTPClientConfig -> Maybe Word32 -> Int
+xftpReqTimeout cfg@XFTPClientConfig {xftpNetworkConfig = NetworkConfig {tcpTimeout}} chunkSize_ =
+  maybe tcpTimeout (chunkTimeout cfg) chunkSize_
+
 chunkTimeout :: XFTPClientConfig -> Word32 -> Int
-chunkTimeout config chunkSize = fromIntegral $ (fromIntegral chunkSize * uploadTimeoutPerMb config) `div` mb 1
+chunkTimeout XFTPClientConfig {xftpNetworkConfig = NetworkConfig {tcpTimeout, tcpTimeoutPerKb}} sz =
+  tcpTimeout + fromIntegral (min ((fromIntegral sz `div` 1024) * tcpTimeoutPerKb) (fromIntegral (maxBound :: Int)))
 
 deleteXFTPChunk :: XFTPClient -> C.APrivateAuthKey -> SenderId -> ExceptT XFTPClientError IO ()
 deleteXFTPChunk c spKey sId = sendXFTPCommand c spKey sId FDEL Nothing >>= okResponse

src/Simplex/FileTransfer/Protocol.hs

@@ -25,7 +25,7 @@ import Data.List.NonEmpty (NonEmpty (..))
 import Data.Maybe (isNothing)
 import Data.Type.Equality
 import Data.Word (Word32)
-import Simplex.FileTransfer.Transport (VersionXFTP, XFTPErrorType (..), XFTPVersion, pattern VersionXFTP, xftpClientHandshake)
+import Simplex.FileTransfer.Transport (XFTPErrorType (..), XFTPVersion, xftpClientHandshakeStub)
 import Simplex.Messaging.Client (authTransmission)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding
@@ -39,8 +39,8 @@ import Simplex.Messaging.Protocol
     ProtocolErrorType (..),
     ProtocolMsgTag (..),
     ProtocolType (..),
-    RcvPublicDhKey,
     RcvPublicAuthKey,
+    RcvPublicDhKey,
     RecipientId,
     SenderId,
     SentRawTransmission,
@@ -48,19 +48,17 @@ import Simplex.Messaging.Protocol
     SndPublicAuthKey,
     Transmission,
     TransmissionForAuth (..),
-    encodeTransmissionForAuth,
+    CorrId (..),
     encodeTransmission,
+    encodeTransmissionForAuth,
     messageTagP,
     tDecodeParseValidate,
     tEncodeBatch1,
     tParse,
   )
-import Simplex.Messaging.Transport (THandleParams (..), TransportError (..))
+import Simplex.Messaging.Transport (THandleParams (..), TransportError (..), TransportPeer (..))
 import Simplex.Messaging.Util ((<$?>))
 
-currentXFTPVersion :: VersionXFTP
-currentXFTPVersion = VersionXFTP 1
-
 xftpBlockSize :: Int
 xftpBlockSize = 16384
 
@@ -144,7 +142,7 @@ instance FilePartyI p => ProtocolMsgTag (FileCommandTag p) where
 instance Protocol XFTPVersion XFTPErrorType FileResponse where
   type ProtoCommand FileResponse = FileCmd
   type ProtoType FileResponse = 'PXFTP
-  protocolClientHandshake = xftpClientHandshake
+  protocolClientHandshake = xftpClientHandshakeStub
   protocolPing = FileCmd SFRecipient PING
   protocolError = \case
     FRErr e -> Just e
@@ -328,12 +326,12 @@ checkParty' c = case testEquality (sFileParty @p) (sFileParty @p') of
   Just Refl -> Just c
   _ -> Nothing
 
-xftpEncodeAuthTransmission :: ProtocolEncoding XFTPVersion e c => THandleParams XFTPVersion -> C.APrivateAuthKey -> Transmission c -> Either TransportError ByteString
-xftpEncodeAuthTransmission thParams pKey (corrId, fId, msg) = do
+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 Nothing (Just pKey) corrId tForAuth
+  xftpEncodeBatch1 . (,tToSend) =<< authTransmission thAuth (Just pKey) (C.cbNonce $ bs corrId) tForAuth
 
-xftpEncodeTransmission :: ProtocolEncoding XFTPVersion e c => THandleParams XFTPVersion -> Transmission c -> Either TransportError ByteString
+xftpEncodeTransmission :: ProtocolEncoding XFTPVersion e c => THandleParams XFTPVersion p -> Transmission c -> Either TransportError ByteString
 xftpEncodeTransmission thParams (corrId, fId, msg) = do
   let t = encodeTransmission thParams (corrId, fId, msg)
   xftpEncodeBatch1 (Nothing, t)
@@ -342,7 +340,7 @@ xftpEncodeTransmission thParams (corrId, fId, msg) = do
 xftpEncodeBatch1 :: SentRawTransmission -> Either TransportError ByteString
 xftpEncodeBatch1 t = first (const TELargeMsg) $ C.pad (tEncodeBatch1 t) xftpBlockSize
 
-xftpDecodeTransmission :: ProtocolEncoding XFTPVersion e c => THandleParams XFTPVersion -> ByteString -> Either XFTPErrorType (SignedTransmission e c)
+xftpDecodeTransmission :: ProtocolEncoding XFTPVersion e c => THandleParams XFTPVersion p -> ByteString -> Either XFTPErrorType (SignedTransmission e c)
 xftpDecodeTransmission thParams t = do
   t' <- first (const BLOCK) $ C.unPad t
   case tParse thParams t' of

src/Simplex/FileTransfer/Server.hs

@@ -9,6 +9,7 @@
 {-# LANGUAGE OverloadedLists #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE TupleSections #-}
 
 module Simplex.FileTransfer.Server where
 
@@ -17,7 +18,8 @@ import Control.Monad
 import Control.Monad.Except
 import Control.Monad.Reader
 import Data.Bifunctor (first)
-import Data.ByteString.Builder (byteString)
+import qualified Data.ByteString.Base64.URL as B64
+import Data.ByteString.Builder (Builder, byteString)
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
 import Data.Int (Int64)
@@ -31,6 +33,7 @@ import Data.Time.Clock (UTCTime (..), diffTimeToPicoseconds, getCurrentTime)
 import Data.Time.Clock.System (SystemTime (..), getSystemTime)
 import Data.Time.Format.ISO8601 (iso8601Show)
 import Data.Word (Word32)
+import qualified Data.X509 as X
 import GHC.IO.Handle (hSetNewlineMode)
 import GHC.Stats (getRTSStats)
 import qualified Network.HTTP.Types as N
@@ -45,19 +48,22 @@ import Simplex.FileTransfer.Server.StoreLog
 import Simplex.FileTransfer.Transport
 import qualified Simplex.Messaging.Crypto as C
 import qualified Simplex.Messaging.Crypto.Lazy as LC
-import qualified Simplex.Messaging.Encoding.Base64.URL as U
+import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
-import Simplex.Messaging.Protocol (CorrId, RcvPublicAuthKey, RcvPublicDhKey, RecipientId, TransmissionAuth)
+import Simplex.Messaging.Protocol (CorrId (..), RcvPublicAuthKey, RcvPublicDhKey, RecipientId, TransmissionAuth)
 import Simplex.Messaging.Server (dummyVerifyCmd, verifyCmdAuthorization)
 import Simplex.Messaging.Server.Expiration
 import Simplex.Messaging.Server.Stats
-import Simplex.Messaging.Transport (THandleParams (..))
+import Simplex.Messaging.TMap (TMap)
+import qualified Simplex.Messaging.TMap as TM
+import Simplex.Messaging.Transport (SessionId, THandleAuth (..), THandleParams (..), TransportPeer (..))
 import Simplex.Messaging.Transport.Buffer (trimCR)
 import Simplex.Messaging.Transport.HTTP2
 import Simplex.Messaging.Transport.HTTP2.File (fileBlockSize)
 import Simplex.Messaging.Transport.HTTP2.Server
-import Simplex.Messaging.Transport.Server (runTCPServer)
+import Simplex.Messaging.Transport.Server (runTCPServer, tlsServerCredentials)
 import Simplex.Messaging.Util
+import Simplex.Messaging.Version (isCompatible)
 import System.Exit (exitFailure)
 import System.FilePath ((</>))
 import System.IO (hPrint, hPutStrLn, universalNewlineMode)
@@ -69,7 +75,7 @@ import qualified UnliftIO.Exception as E
 type M a = ReaderT XFTPEnv IO a
 
 data XFTPTransportRequest = XFTPTransportRequest
-  { thParams :: THandleParams XFTPVersion,
+  { thParams :: THandleParamsXFTP 'TServer,
     reqBody :: HTTP2Body,
     request :: H.Request,
     sendResponse :: H.Response -> IO ()
@@ -83,6 +89,10 @@ runXFTPServer cfg = do
 runXFTPServerBlocking :: TMVar Bool -> XFTPServerConfig -> IO ()
 runXFTPServerBlocking started cfg = newXFTPServerEnv cfg >>= runReaderT (xftpServer cfg started)
 
+data Handshake
+  = HandshakeSent C.PrivateKeyX25519
+  | HandshakeAccepted (THandleAuth 'TServer) VersionXFTP
+
 xftpServer :: XFTPServerConfig -> TMVar Bool -> M ()
 xftpServer cfg@XFTPServerConfig {xftpPort, transportConfig, inactiveClientExpiration, fileExpiration} started = do
   mapM_ (expireServerFiles Nothing) fileExpiration
@@ -92,12 +102,62 @@ xftpServer cfg@XFTPServerConfig {xftpPort, transportConfig, inactiveClientExpira
     runServer :: M ()
     runServer = do
       serverParams <- asks tlsServerParams
+      let (chain, pk) = tlsServerCredentials serverParams
+      signKey <- liftIO $ case C.x509ToPrivate (pk, []) >>= C.privKey of
+        Right pk' -> pure pk'
+        Left e -> putStrLn ("servers has no valid key: " <> show e) >> exitFailure
       env <- ask
-      liftIO $
-        runHTTP2Server started xftpPort defaultHTTP2BufferSize serverParams transportConfig inactiveClientExpiration $ \sessionId r sendResponse -> do
-          reqBody <- getHTTP2Body r xftpBlockSize
-          let thParams = THandleParams {sessionId, blockSize = xftpBlockSize, thVersion = currentXFTPVersion, thAuth = Nothing, implySessId = False, batch = True}
-          processRequest XFTPTransportRequest {thParams, request = r, reqBody, sendResponse} `runReaderT` env
+      sessions <- atomically TM.empty
+      let cleanup sessionId = atomically $ TM.delete sessionId sessions
+      liftIO . runHTTP2Server started xftpPort defaultHTTP2BufferSize serverParams transportConfig inactiveClientExpiration cleanup $ \sessionId sessionALPN r sendResponse -> do
+        reqBody <- getHTTP2Body r xftpBlockSize
+        let thParams0 = THandleParams {sessionId, blockSize = xftpBlockSize, thVersion = VersionXFTP 1, thAuth = Nothing, implySessId = False, batch = True}
+            req0 = XFTPTransportRequest {thParams = thParams0, request = r, reqBody, sendResponse}
+        flip runReaderT env $ case sessionALPN of
+          Nothing -> processRequest req0
+          Just "xftp/1" ->
+            xftpServerHandshakeV1 chain signKey sessions req0 >>= \case
+              Nothing -> pure () -- handshake response sent
+              Just thParams -> processRequest req0 {thParams} -- proceed with new version (XXX: may as well switch the request handler here)
+          _ -> liftIO . sendResponse $ H.responseNoBody N.ok200 [] -- shouldn't happen: means server picked handshake protocol it doesn't know about
+    xftpServerHandshakeV1 :: X.CertificateChain -> C.APrivateSignKey -> TMap SessionId Handshake -> XFTPTransportRequest -> M (Maybe (THandleParams XFTPVersion 'TServer))
+    xftpServerHandshakeV1 chain serverSignKey sessions XFTPTransportRequest {thParams = thParams@THandleParams {sessionId}, reqBody = HTTP2Body {bodyHead}, sendResponse} = do
+      s <- atomically $ TM.lookup sessionId sessions
+      r <- runExceptT $ case s of
+        Nothing -> processHello
+        Just (HandshakeSent pk) -> processClientHandshake pk
+        Just (HandshakeAccepted auth v) -> pure $ Just thParams {thAuth = Just auth, thVersion = v}
+      either sendError pure r
+      where
+        processHello = do
+          unless (B.null bodyHead) $ throwError HANDSHAKE
+          (k, pk) <- atomically . C.generateKeyPair =<< asks random
+          atomically $ TM.insert sessionId (HandshakeSent pk) sessions
+          let authPubKey = (chain, C.signX509 serverSignKey $ C.publicToX509 k)
+          let hs = XFTPServerHandshake {xftpVersionRange = supportedFileServerVRange, sessionId, authPubKey}
+          shs <- encodeXftp hs
+          liftIO . sendResponse $ H.responseBuilder N.ok200 [] shs
+          pure Nothing
+        processClientHandshake pk = do
+          unless (B.length bodyHead == xftpBlockSize) $ throwError HANDSHAKE
+          body <- liftHS $ C.unPad bodyHead
+          XFTPClientHandshake {xftpVersion, keyHash} <- liftHS $ smpDecode body
+          kh <- asks serverIdentity
+          unless (keyHash == kh) $ throwError HANDSHAKE
+          unless (xftpVersion `isCompatible` supportedFileServerVRange) $ throwError HANDSHAKE
+          let auth = THAuthServer {serverPrivKey = pk, sessSecret' = Nothing}
+          atomically $ TM.insert sessionId (HandshakeAccepted auth xftpVersion) sessions
+          liftIO . sendResponse $ H.responseNoBody N.ok200 []
+          pure Nothing
+        sendError :: XFTPErrorType -> M (Maybe (THandleParams XFTPVersion 'TServer))
+        sendError err = do
+          runExceptT (encodeXftp err) >>= \case
+            Right bs -> liftIO . sendResponse $ H.responseBuilder N.ok200 [] bs
+            Left _ -> logError $ "Error encoding handshake error: " <> tshow err
+          pure Nothing
+        encodeXftp :: Encoding a => a -> ExceptT XFTPErrorType (ReaderT XFTPEnv IO) Builder
+        encodeXftp a = byteString <$> liftHS (C.pad (smpEncode a) xftpBlockSize)
+        liftHS = liftEitherWith (const HANDSHAKE)
 
     stopServer :: M ()
     stopServer = do
@@ -183,7 +243,7 @@ xftpServer cfg@XFTPServerConfig {xftpPort, transportConfig, inactiveClientExpira
           role <- newTVarIO CPRNone
           cpLoop h role
           where
-            cpLoop h role  = do
+            cpLoop h role = do
               s <- trimCR <$> B.hGetLine h
               case strDecode s of
                 Right CPQuit -> hClose h
@@ -217,12 +277,13 @@ xftpServer cfg@XFTPServerConfig {xftpPort, transportConfig, inactiveClientExpira
               CPQuit -> pure ()
               CPSkip -> pure ()
               where
-                withUserRole action = readTVarIO role >>= \case
-                  CPRAdmin -> action
-                  CPRUser -> action
-                  _ -> do
-                    logError "Unauthorized control port command"
-                    hPutStrLn h "AUTH"
+                withUserRole action =
+                  readTVarIO role >>= \case
+                    CPRAdmin -> action
+                    CPRUser -> action
+                    _ -> do
+                      logError "Unauthorized control port command"
+                      hPutStrLn h "AUTH"
 
 data ServerFile = ServerFile
   { filePath :: FilePath,
@@ -235,10 +296,11 @@ processRequest XFTPTransportRequest {thParams, reqBody = body@HTTP2Body {bodyHea
   | B.length bodyHead /= xftpBlockSize = sendXFTPResponse ("", "", FRErr BLOCK) Nothing
   | otherwise = do
       case xftpDecodeTransmission thParams bodyHead of
-        Right (sig_, signed, (corrId, fId, cmdOrErr)) -> do
+        Right (sig_, signed, (corrId, fId, cmdOrErr)) ->
           case cmdOrErr of
             Right cmd -> do
-              verifyXFTPTransmission sig_ signed fId cmd >>= \case
+              let THandleParams {thAuth} = thParams
+              verifyXFTPTransmission ((,C.cbNonce (bs corrId)) <$> thAuth) sig_ signed fId cmd >>= \case
                 VRVerified req -> uncurry send =<< processXFTPRequest body req
                 VRFailed -> send (FRErr AUTH) Nothing
             Left e -> send (FRErr e) Nothing
@@ -246,7 +308,6 @@ processRequest XFTPTransportRequest {thParams, reqBody = body@HTTP2Body {bodyHea
             send resp = sendXFTPResponse (corrId, fId, resp)
         Left e -> sendXFTPResponse ("", "", FRErr e) Nothing
   where
-    sendXFTPResponse :: (CorrId, XFTPFileId, FileResponse) -> Maybe ServerFile -> M ()
     sendXFTPResponse (corrId, fId, resp) serverFile_ = do
       let t_ = xftpEncodeTransmission thParams (corrId, fId, resp)
       liftIO $ sendResponse $ H.responseStreaming N.ok200 [] $ streamBody t_
@@ -265,8 +326,8 @@ processRequest XFTPTransportRequest {thParams, reqBody = body@HTTP2Body {bodyHea
 
 data VerificationResult = VRVerified XFTPRequest | VRFailed
 
-verifyXFTPTransmission :: Maybe TransmissionAuth -> ByteString -> XFTPFileId -> FileCmd -> M VerificationResult
-verifyXFTPTransmission tAuth authorized fId cmd =
+verifyXFTPTransmission :: Maybe (THandleAuth 'TServer, C.CbNonce) -> Maybe TransmissionAuth -> ByteString -> XFTPFileId -> FileCmd -> M VerificationResult
+verifyXFTPTransmission auth_ tAuth authorized fId cmd =
   case cmd of
     FileCmd SFSender (FNEW file rcps auth') -> pure $ XFTPReqNew file rcps auth' `verifyWith` sndKey file
     FileCmd SFRecipient PING -> pure $ VRVerified XFTPReqPing
@@ -281,7 +342,7 @@ verifyXFTPTransmission tAuth authorized fId cmd =
           Right (fr, k) -> XFTPReqCmd fId fr cmd `verifyWith` k
           _ -> maybe False (dummyVerifyCmd Nothing authorized) tAuth `seq` VRFailed
     -- TODO verify with DH authorization
-    req `verifyWith` k = if verifyCmdAuthorization Nothing tAuth authorized k then VRVerified req else VRFailed
+    req `verifyWith` k = if verifyCmdAuthorization auth_ tAuth authorized k then VRVerified req else VRFailed
 
 processXFTPRequest :: HTTP2Body -> XFTPRequest -> M (FileResponse, Maybe ServerFile)
 processXFTPRequest HTTP2Body {bodyPart} = \case
@@ -374,7 +435,7 @@ processXFTPRequest HTTP2Body {bodyPart} = \case
               \used -> let used' = used + fromIntegral size in if used' <= quota then (True, used') else (False, used)
           receive = do
             path <- asks $ filesPath . config
-            let fPath = path </> B.unpack (U.encode senderId)
+            let fPath = path </> B.unpack (B64.encode senderId)
             receiveChunk (XFTPRcvChunkSpec fPath size digest) >>= \case
               Right () -> do
                 stats <- asks serverStats
@@ -395,18 +456,20 @@ processXFTPRequest HTTP2Body {bodyPart} = \case
     sendServerFile :: FileRec -> RcvPublicDhKey -> M (FileResponse, Maybe ServerFile)
     sendServerFile FileRec {senderId, filePath, fileInfo = FileInfo {size}} rDhKey = do
       readTVarIO filePath >>= \case
-        Just path -> do
-          g <- asks random
-          (sDhKey, spDhKey) <- atomically $ C.generateKeyPair g
-          let dhSecret = C.dh' rDhKey spDhKey
-          cbNonce <- atomically $ C.randomCbNonce g
-          case LC.cbInit dhSecret cbNonce of
-            Right sbState -> do
-              stats <- asks serverStats
-              atomically $ modifyTVar' (fileDownloads stats) (+ 1)
-              atomically $ updatePeriodStats (filesDownloaded stats) senderId
-              pure (FRFile sDhKey cbNonce, Just ServerFile {filePath = path, fileSize = size, sbState})
-            _ -> pure (FRErr INTERNAL, Nothing)
+        Just path -> ifM (doesFileExist path) sendFile (pure (FRErr AUTH, Nothing))
+          where
+            sendFile = do
+              g <- asks random
+              (sDhKey, spDhKey) <- atomically $ C.generateKeyPair g
+              let dhSecret = C.dh' rDhKey spDhKey
+              cbNonce <- atomically $ C.randomCbNonce g
+              case LC.cbInit dhSecret cbNonce of
+                Right sbState -> do
+                  stats <- asks serverStats
+                  atomically $ modifyTVar' (fileDownloads stats) (+ 1)
+                  atomically $ updatePeriodStats (filesDownloaded stats) senderId
+                  pure (FRFile sDhKey cbNonce, Just ServerFile {filePath = path, fileSize = size, sbState})
+                _ -> pure (FRErr INTERNAL, Nothing)
         _ -> pure (FRErr NO_FILE, Nothing)
 
     deleteServerFile :: FileRec -> M FileResponse

src/Simplex/FileTransfer/Server/Env.hs

@@ -2,19 +2,23 @@
 {-# LANGUAGE DuplicateRecordFields #-}
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE KindSignatures #-}
+{-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE StrictData #-}
 
 module Simplex.FileTransfer.Server.Env where
 
-import Control.Logger.Simple (logInfo)
+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 (..))
@@ -27,7 +31,8 @@ import Simplex.FileTransfer.Server.StoreLog
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Protocol (BasicAuth, RcvPublicAuthKey)
 import Simplex.Messaging.Server.Expiration
-import Simplex.Messaging.Transport.Server (TransportServerConfig, loadFingerprint, loadTLSServerParams)
+import Simplex.Messaging.Transport (ALPN)
+import Simplex.Messaging.Transport.Server (TransportServerConfig (..), loadFingerprint, loadTLSServerParams)
 import Simplex.Messaging.Util (tshow)
 import System.IO (IOMode (..))
 import UnliftIO.STM
@@ -94,6 +99,9 @@ defaultFileExpiration =
       checkInterval = 2 * 3600 -- seconds, 2 hours
     }
 
+supportedXFTPhandshakes :: [ALPN]
+supportedXFTPhandshakes = ["xftp/1"]
+
 newXFTPServerEnv :: XFTPServerConfig -> IO XFTPEnv
 newXFTPServerEnv config@XFTPServerConfig {storeLogFile, fileSizeQuota, caCertificateFile, certificateFile, privateKeyFile} = do
   random <- liftIO C.newRandom
@@ -104,7 +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
+  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}

src/Simplex/FileTransfer/Server/StoreLog.hs

@@ -22,6 +22,7 @@ import Control.Concurrent.STM
 import Control.Monad.Except
 import qualified Data.Attoparsec.ByteString.Char8 as A
 import qualified Data.ByteString.Char8 as B
+import qualified Data.ByteString.Lazy.Char8 as LB
 import Data.Composition ((.:), (.:.))
 import Data.List.NonEmpty (NonEmpty)
 import qualified Data.List.NonEmpty as L
@@ -88,7 +89,7 @@ readWriteFileStore f st = do
   pure s
 
 readFileStore :: FilePath -> FileStore -> IO ()
-readFileStore f st = mapM_ addFileLogRecord . B.lines =<< B.readFile f
+readFileStore f st = mapM_ (addFileLogRecord . LB.toStrict) . LB.lines =<< LB.readFile f
   where
     addFileLogRecord s = case strDecode s of
       Left e -> B.putStrLn $ "Log parsing error (" <> B.pack e <> "): " <> B.take 100 s

src/Simplex/FileTransfer/Transport.hs

@@ -1,3 +1,4 @@
+{-# LANGUAGE DataKinds #-}
 {-# LANGUAGE DuplicateRecordFields #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE MultiWayIf #-}
@@ -9,9 +10,17 @@
 
 module Simplex.FileTransfer.Transport
   ( supportedFileServerVRange,
-    xftpClientHandshake, -- stub
-    XFTPVersion,
+    authCmdsXFTPVersion,
+    xftpClientHandshakeStub,
+    XFTPClientHandshake (..),
+    -- xftpClientHandshake,
+    XFTPServerHandshake (..),
+    -- xftpServerHandshake,
+    THandleXFTP,
+    THandleParamsXFTP,
     VersionXFTP,
+    VersionRangeXFTP,
+    XFTPVersion,
     pattern VersionXFTP,
     XFTPErrorType (..),
     XFTPRcvChunkSpec (..),
@@ -30,20 +39,21 @@ import Control.Monad.Except
 import Control.Monad.IO.Class
 import qualified Data.Aeson.TH as J
 import qualified Data.Attoparsec.ByteString.Char8 as A
-import Data.Bifunctor (first)
+import Data.Bifunctor (bimap, first)
 import qualified Data.ByteArray as BA
 import Data.ByteString.Builder (Builder, byteString)
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
 import qualified Data.ByteString.Lazy.Char8 as LB
 import Data.Word (Word16, Word32)
+import qualified Data.X509 as X
 import qualified Simplex.Messaging.Crypto as C
 import qualified Simplex.Messaging.Crypto.Lazy as LC
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Parsers
 import Simplex.Messaging.Protocol (CommandError)
-import Simplex.Messaging.Transport (HandshakeError (..), THandle, TransportError (..))
+import Simplex.Messaging.Transport (HandshakeError (..), SessionId, THandle (..), THandleParams (..), TransportError (..), TransportPeer (..))
 import Simplex.Messaging.Transport.HTTP2.File
 import Simplex.Messaging.Util (bshow)
 import Simplex.Messaging.Version
@@ -68,15 +78,58 @@ type VersionRangeXFTP = VersionRange XFTPVersion
 pattern VersionXFTP :: Word16 -> VersionXFTP
 pattern VersionXFTP v = Version v
 
+type THandleXFTP c p = THandle XFTPVersion c p
+type THandleParamsXFTP p = THandleParams XFTPVersion p
+
 initialXFTPVersion :: VersionXFTP
 initialXFTPVersion = VersionXFTP 1
 
-supportedFileServerVRange :: VersionRangeXFTP
-supportedFileServerVRange = mkVersionRange initialXFTPVersion initialXFTPVersion
+authCmdsXFTPVersion :: VersionXFTP
+authCmdsXFTPVersion = VersionXFTP 2
 
--- XFTP protocol does not support handshake
-xftpClientHandshake :: c -> C.KeyPairX25519 -> C.KeyHash -> VersionRangeXFTP -> ExceptT TransportError IO (THandle XFTPVersion c)
-xftpClientHandshake _c _ks _keyHash _xftpVRange = throwError $ TEHandshake VERSION
+currentXFTPVersion :: VersionXFTP
+currentXFTPVersion = VersionXFTP 2
+
+supportedFileServerVRange :: VersionRangeXFTP
+supportedFileServerVRange = mkVersionRange initialXFTPVersion currentXFTPVersion
+
+-- XFTP protocol does not use this handshake method
+xftpClientHandshakeStub :: c -> Maybe C.KeyPairX25519 -> C.KeyHash -> VersionRangeXFTP -> ExceptT TransportError IO (THandle XFTPVersion c 'TClient)
+xftpClientHandshakeStub _c _ks _keyHash _xftpVRange = throwError $ TEHandshake VERSION
+
+data XFTPServerHandshake = XFTPServerHandshake
+  { xftpVersionRange :: VersionRangeXFTP,
+    sessionId :: SessionId,
+    -- | pub key to agree shared secrets for command authorization and entity ID encryption.
+    authPubKey :: (X.CertificateChain, X.SignedExact X.PubKey)
+  }
+
+data XFTPClientHandshake = XFTPClientHandshake
+  { -- | agreed XFTP server protocol version
+    xftpVersion :: VersionXFTP,
+    -- | server identity - CA certificate fingerprint
+    keyHash :: C.KeyHash
+  }
+
+instance Encoding XFTPClientHandshake where
+  smpEncode XFTPClientHandshake {xftpVersion, keyHash} =
+    smpEncode (xftpVersion, keyHash)
+  smpP = do
+    (xftpVersion, keyHash) <- smpP
+    Tail _compat <- smpP
+    pure XFTPClientHandshake {xftpVersion, keyHash}
+
+instance Encoding XFTPServerHandshake where
+  smpEncode XFTPServerHandshake {xftpVersionRange, sessionId, authPubKey} =
+    smpEncode (xftpVersionRange, sessionId, auth)
+    where
+      auth = bimap C.encodeCertChain C.SignedObject authPubKey
+  smpP = do
+    (xftpVersionRange, sessionId) <- smpP
+    cert <- C.certChainP
+    C.SignedObject key <- smpP
+    Tail _compat <- smpP
+    pure XFTPServerHandshake {xftpVersionRange, sessionId, authPubKey = (cert, key)}
 
 sendEncFile :: Handle -> (Builder -> IO ()) -> LC.SbState -> Word32 -> IO ()
 sendEncFile h send = go
@@ -139,6 +192,8 @@ data XFTPErrorType
     BLOCK
   | -- | incorrect SMP session ID (TLS Finished message / tls-unique binding RFC5929)
     SESSION
+  | -- | incorrect handshake command
+    HANDSHAKE
   | -- | SMP command is unknown or has invalid syntax
     CMD {cmdErr :: CommandError}
   | -- | command authorization error - bad signature or non-existing SMP queue
@@ -181,6 +236,7 @@ instance Encoding XFTPErrorType where
   smpEncode = \case
     BLOCK -> "BLOCK"
     SESSION -> "SESSION"
+    HANDSHAKE -> "HANDSHAKE"
     CMD err -> "CMD " <> smpEncode err
     AUTH -> "AUTH"
     SIZE -> "SIZE"
@@ -199,6 +255,7 @@ instance Encoding XFTPErrorType where
     A.takeTill (== ' ') >>= \case
       "BLOCK" -> pure BLOCK
       "SESSION" -> pure SESSION
+      "HANDSHAKE" -> pure HANDSHAKE
       "CMD" -> CMD <$> _smpP
       "AUTH" -> pure AUTH
       "SIZE" -> pure SIZE

src/Simplex/Messaging/Agent.hs

@@ -82,6 +82,7 @@ module Simplex.Messaging.Agent
     setNtfServers,
     setNetworkConfig,
     getNetworkConfig,
+    setUserNetworkInfo,
     reconnectAllServers,
     registerNtfToken,
     verifyNtfToken,
@@ -402,17 +403,35 @@ testProtocolServer c userId srv = withAgentEnv' c $ case protocolTypeI @p of
   SPXFTP -> runXFTPServerTest c userId srv
   SPNTF -> runNTFServerTest c userId srv
 
--- | set SOCKS5 proxy on/off and optionally set TCP timeout
+-- | set SOCKS5 proxy on/off and optionally set TCP timeouts for fast network
 setNetworkConfig :: AgentClient -> NetworkConfig -> IO ()
-setNetworkConfig c cfg' = do
-  cfg <- atomically $ do
-    swapTVar (useNetworkConfig c) cfg'
-  when (cfg /= cfg') $ reconnectAllServers c
+setNetworkConfig c@AgentClient {useNetworkConfig} cfg' = do
+  changed <- atomically $ do
+    (_, cfg) <- readTVar useNetworkConfig
+    if cfg == cfg'
+      then pure False
+      else True <$ (writeTVar useNetworkConfig $! (slowNetworkConfig cfg', cfg'))
+  when changed $ reconnectAllServers c
 
+-- returns fast network config
 getNetworkConfig :: AgentClient -> IO NetworkConfig
-getNetworkConfig = readTVarIO . useNetworkConfig
+getNetworkConfig = fmap snd . readTVarIO . useNetworkConfig
 {-# INLINE getNetworkConfig #-}
 
+setUserNetworkInfo :: AgentClient -> UserNetworkInfo -> IO ()
+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
@@ -769,7 +788,7 @@ compatibleContactUri (CRContactUri ConnReqUriData {crAgentVRange, crSmpQueues =
   AgentConfig {smpClientVRange, smpAgentVRange} <- asks config
   pure $
     (,)
-      <$> (qUri `compatibleVersion` smpClientVRange) 
+      <$> (qUri `compatibleVersion` smpClientVRange)
       <*> (crAgentVRange `compatibleVersion` smpAgentVRange pqSup)
 
 versionPQSupport_ :: VersionSMPA -> Maybe CR.VersionE2E -> PQSupport
@@ -1267,6 +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
+          lift $ waitForUserNetwork c
           resp <- tryError $ case msgType of
             AM_CONN_INFO -> sendConfirmation c sq msgBody
             AM_CONN_INFO_REPLY -> sendConfirmation c sq msgBody
@@ -2047,7 +2067,7 @@ processSMPTransmission c@AgentClient {smpClients, subQ} (tSess@(_, srv, _), _v,
               pure ack'
             where
               queueDrained = case conn of
-                DuplexConnection _ _ sqs -> void $ enqueueMessages c cData sqs SMP.noMsgFlags $ QCONT (sndAddress rq)
+                DuplexConnection _ _ sqs -> void $ enqueueMessages c cData sqs SMP.noMsgFlags $ A_QCONT (sndAddress rq)
                 _ -> pure ()
               processClientMsg srvTs msgFlags msgBody = do
                 clientMsg@SMP.ClientMsgEnvelope {cmHeader = SMP.PubHeader phVer e2ePubKey_} <-
@@ -2096,7 +2116,7 @@ processSMPTransmission c@AgentClient {smpClients, subQ} (tSess@(_, srv, _), _v,
                                 notify $ MSG msgMeta msgFlags body
                                 pure ACKPending
                               A_RCVD rcpts -> qDuplex conn'' "RCVD" $ messagesRcvd rcpts msgMeta
-                              QCONT addr -> qDuplexAckDel conn'' "QCONT" $ continueSending srvMsgId addr
+                              A_QCONT addr -> qDuplexAckDel conn'' "QCONT" $ continueSending srvMsgId addr
                               QADD qs -> qDuplexAckDel conn'' "QADD" $ qAddMsg srvMsgId qs
                               QKEY qs -> qDuplexAckDel conn'' "QKEY" $ qKeyMsg srvMsgId qs
                               QUSE qs -> qDuplexAckDel conn'' "QUSE" $ qUseMsg srvMsgId qs
@@ -2310,6 +2330,7 @@ processSMPTransmission c@AgentClient {smpClients, subQ} (tSess@(_, srv, _), _v,
                 atomically $
                   TM.lookup (qAddress sq) (smpDeliveryWorkers c)
                     >>= mapM_ (\(_, retryLock) -> tryPutTMVar retryLock ())
+                notify QCONT
               Nothing -> qError "QCONT: queue address not found"
 
           messagesRcvd :: NonEmpty AMessageReceipt -> MsgMeta -> Connection 'CDuplex -> AM ACKd
@@ -2351,10 +2372,10 @@ processSMPTransmission c@AgentClient {smpClients, subQ} (tSess@(_, srv, _), _v,
                     case L.nonEmpty keepSqs of
                       Just sqs' -> do
                         -- move inside case?
-                        withStore' c $ \db -> mapM_ (deleteConnSndQueue db connId) delSqs
                         sq_@SndQueue {sndPublicKey, e2ePubKey} <- lift $ newSndQueue userId connId qInfo
-                        let sq'' = (sq_ :: NewSndQueue) {primary = True, dbReplaceQueueId = Just dbQueueId}
-                        sq2 <- withStore c $ \db -> addConnSndQueue db connId sq''
+                        sq2 <- withStore c $ \db -> do
+                          liftIO $ mapM_ (deleteConnSndQueue db connId) delSqs
+                          addConnSndQueue db connId (sq_ :: NewSndQueue) {primary = True, dbReplaceQueueId = Just dbQueueId}
                         case (sndPublicKey, e2ePubKey) of
                           (Just sndPubKey, Just dhPublicKey) -> do
                             logServer "<--" c srv rId $ "MSG <QADD>:" <> logSecret srvMsgId <> " " <> logSecret (senderId queueAddress)

src/Simplex/Messaging/Agent/Client.hs

@@ -27,6 +27,7 @@ module Simplex.Messaging.Agent.Client
     withConnLock,
     withConnLocks,
     withInvLock,
+    withLockMap,
     closeAgentClient,
     closeProtocolServerClients,
     reconnectServerClients,
@@ -80,6 +81,7 @@ module Simplex.Messaging.Agent.Client
     agentClientStore,
     agentDRG,
     getAgentSubscriptions,
+    slowNetworkConfig,
     Worker (..),
     SessionVar (..),
     SubscriptionsInfo (..),
@@ -99,6 +101,11 @@ module Simplex.Messaging.Agent.Client
     agentOperations,
     agentOperationBracket,
     waitUntilActive,
+    UserNetworkInfo (..),
+    UserNetworkType (..),
+    UserNetworkState (..),
+    UNSOffline (..),
+    waitForUserNetwork,
     throwWhenInactive,
     throwWhenNoDelivery,
     beginAgentOperation,
@@ -132,7 +139,7 @@ import Control.Applicative ((<|>))
 import Control.Concurrent (ThreadId, forkIO, threadDelay)
 import Control.Concurrent.Async (Async, uninterruptibleCancel)
 import Control.Concurrent.STM (retry, throwSTM)
-import Control.Exception (AsyncException (..))
+import Control.Exception (AsyncException (..), BlockedIndefinitelyOnSTM (..))
 import Control.Logger.Simple
 import Control.Monad
 import Control.Monad.Except
@@ -142,11 +149,12 @@ import Crypto.Random (ChaChaDRG)
 import qualified Data.Aeson as J
 import qualified Data.Aeson.TH as J
 import Data.Bifunctor (bimap, first, second)
+import Data.ByteString.Base64
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
-import Data.Composition ((.:.))
 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
@@ -157,7 +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)
@@ -165,7 +173,7 @@ import Simplex.FileTransfer.Client (XFTPChunkSpec (..), XFTPClient, XFTPClientCo
 import qualified Simplex.FileTransfer.Client as X
 import Simplex.FileTransfer.Description (ChunkReplicaId (..), FileDigest (..), kb)
 import Simplex.FileTransfer.Protocol (FileInfo (..), FileResponse)
-import Simplex.FileTransfer.Transport (XFTPRcvChunkSpec (..), XFTPErrorType (DIGEST), XFTPVersion)
+import Simplex.FileTransfer.Transport (XFTPErrorType (DIGEST), XFTPRcvChunkSpec (..), XFTPVersion)
 import Simplex.FileTransfer.Types (DeletedSndChunkReplica (..), NewSndChunkReplica (..), RcvFileChunkReplica (..), SndFileChunk (..), SndFileChunkReplica (..))
 import Simplex.FileTransfer.Util (uniqueCombine)
 import Simplex.Messaging.Agent.Env.SQLite
@@ -181,7 +189,6 @@ import Simplex.Messaging.Client
 import Simplex.Messaging.Client.Agent ()
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding
-import Simplex.Messaging.Encoding.Base64 (encode)
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Notifications.Client
 import Simplex.Messaging.Notifications.Protocol
@@ -195,6 +202,7 @@ import Simplex.Messaging.Protocol
     ErrorType,
     MsgFlags (..),
     MsgId,
+    NtfPublicAuthKey,
     NtfServer,
     NtfServerWithAuth,
     ProtoServer,
@@ -206,22 +214,22 @@ import Simplex.Messaging.Protocol
     QueueIdsKeys (..),
     RcvMessage (..),
     RcvNtfPublicDhKey,
-    NtfPublicAuthKey,
     SMPMsgMeta (..),
     SProtocolType (..),
     SndPublicAuthKey,
     SubscriptionMode (..),
     UserProtocol,
+    VersionRangeSMPC,
+    VersionSMPC,
     XFTPServer,
     XFTPServerWithAuth,
-    VersionSMPC,
-    VersionRangeSMPC,
     sameSrvAddr',
   )
 import qualified Simplex.Messaging.Protocol as SMP
-import Simplex.Messaging.Transport (SMPVersion)
+import Simplex.Messaging.Session
 import Simplex.Messaging.TMap (TMap)
 import qualified Simplex.Messaging.TMap as TM
+import Simplex.Messaging.Transport (SMPVersion)
 import Simplex.Messaging.Transport.Client (TransportHost)
 import Simplex.Messaging.Util
 import Simplex.Messaging.Version
@@ -233,11 +241,6 @@ import UnliftIO.Directory (doesFileExist, getTemporaryDirectory, removeFile)
 import qualified UnliftIO.Exception as E
 import UnliftIO.STM
 
-data SessionVar a = SessionVar
-  { sessionVar :: TMVar a,
-    sessionVarId :: Int
-  }
-
 type ClientVar msg = SessionVar (Either AgentErrorType (Client msg))
 
 type SMPClientVar = ClientVar SMP.BrokerMsg
@@ -264,7 +267,8 @@ data AgentClient = AgentClient
     ntfClients :: TMap NtfTransportSession NtfClientVar,
     xftpServers :: TMap UserId (NonEmpty XFTPServerWithAuth),
     xftpClients :: TMap XFTPTransportSession XFTPClientVar,
-    useNetworkConfig :: TVar NetworkConfig,
+    useNetworkConfig :: TVar (NetworkConfig, NetworkConfig), -- (slow, fast) networks
+    userNetworkState :: TVar UserNetworkState,
     subscrConns :: TVar (Set ConnId),
     activeSubs :: TRcvQueues,
     pendingSubs :: TRcvQueues,
@@ -395,6 +399,24 @@ data AgentStatsKey = AgentStatsKey
   }
   deriving (Eq, Ord, Show)
 
+data UserNetworkInfo = UserNetworkInfo
+  { networkType :: UserNetworkType,
+    online :: Bool
+  }
+  deriving (Show)
+
+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
@@ -410,7 +432,8 @@ newAgentClient clientId InitialAgentServers {smp, ntf, xftp, netCfg} agentEnv =
   ntfClients <- TM.empty
   xftpServers <- newTVar xftp
   xftpClients <- TM.empty
-  useNetworkConfig <- newTVar netCfg
+  useNetworkConfig <- newTVar (slowNetworkConfig netCfg, netCfg)
+  userNetworkState <- newTVar $ UserNetworkState UNOther Nothing
   subscrConns <- newTVar S.empty
   activeSubs <- RQ.empty
   pendingSubs <- RQ.empty
@@ -445,6 +468,7 @@ newAgentClient clientId InitialAgentServers {smp, ntf, xftp, netCfg} agentEnv =
         xftpServers,
         xftpClients,
         useNetworkConfig,
+        userNetworkState,
         subscrConns,
         activeSubs,
         pendingSubs,
@@ -469,6 +493,13 @@ newAgentClient clientId InitialAgentServers {smp, ntf, xftp, netCfg} agentEnv =
         agentEnv
       }
 
+slowNetworkConfig :: NetworkConfig -> NetworkConfig
+slowNetworkConfig cfg@NetworkConfig {tcpConnectTimeout, tcpTimeout, tcpTimeoutPerKb} =
+  cfg {tcpConnectTimeout = slow tcpConnectTimeout, tcpTimeout = slow tcpTimeout, tcpTimeoutPerKb = slow tcpTimeoutPerKb}
+  where
+    slow :: Integral a => a -> a
+    slow t = (t * 3) `div` 2
+
 agentClientStore :: AgentClient -> SQLiteStore
 agentClientStore AgentClient {agentEnv = Env {store}} = store
 {-# INLINE agentClientStore #-}
@@ -514,9 +545,9 @@ instance ProtocolServerClient XFTPVersion XFTPErrorType FileResponse where
   clientSessionTs = X.xftpSessionTs
 
 getSMPServerClient :: AgentClient -> SMPTransportSession -> AM SMPClient
-getSMPServerClient c@AgentClient {active, smpClients, msgQ} tSess@(userId, srv, _) = do
+getSMPServerClient c@AgentClient {active, smpClients, msgQ, workerSeq} tSess@(userId, srv, _) = do
   unlessM (readTVarIO active) . throwError $ INACTIVE
-  atomically (getTSessVar c tSess smpClients)
+  atomically (getSessVar workerSeq tSess smpClients)
     >>= either newClient (waitForProtocolClient c tSess)
   where
     -- we resubscribe only on newClient error, but not on waitForProtocolClient error,
@@ -531,7 +562,8 @@ getSMPServerClient c@AgentClient {active, smpClients, msgQ} tSess@(userId, srv,
       g <- asks random
       env <- ask
       liftError' (protocolClientError SMP $ B.unpack $ strEncode srv) $
-        getProtocolClient g tSess cfg (Just msgQ) $ clientDisconnected env v
+        getProtocolClient g tSess cfg (Just msgQ) $
+          clientDisconnected env v
 
     clientDisconnected :: Env -> SMPClientVar -> SMPClient -> IO ()
     clientDisconnected env v client = do
@@ -544,7 +576,7 @@ getSMPServerClient c@AgentClient {active, smpClients, msgQ} tSess@(userId, srv,
         removeClientAndSubs :: IO ([RcvQueue], [ConnId])
         removeClientAndSubs = atomically $ ifM currentActiveClient removeSubs $ pure ([], [])
           where
-            currentActiveClient = (&&) <$> removeTSessVar' v tSess smpClients <*> readTVar active
+            currentActiveClient = (&&) <$> removeSessVar' v tSess smpClients <*> readTVar active
             removeSubs = do
               (qs, cs) <- RQ.getDelSessQueues tSess $ activeSubs c
               RQ.batchAddQueues (pendingSubs c) qs
@@ -563,14 +595,14 @@ getSMPServerClient c@AgentClient {active, smpClients, msgQ} tSess@(userId, srv,
         notifySub connId cmd = atomically $ writeTBQueue (subQ c) ("", connId, APC (sAEntity @e) cmd)
 
 resubscribeSMPSession :: AgentClient -> SMPTransportSession -> AM' ()
-resubscribeSMPSession c@AgentClient {smpSubWorkers} tSess =
+resubscribeSMPSession c@AgentClient {smpSubWorkers, workerSeq} tSess =
   atomically getWorkerVar >>= mapM_ (either newSubWorker (\_ -> pure ()))
   where
     getWorkerVar =
       ifM
         (null <$> getPending)
         (pure Nothing) -- prevent race with cleanup and adding pending queues in another call
-        (Just <$> getTSessVar c tSess smpSubWorkers)
+        (Just <$> getSessVar workerSeq tSess smpSubWorkers)
     newSubWorker v = do
       a <- async $ void (E.tryAny runSubWorker) >> atomically (cleanup v)
       atomically $ putTMVar (sessionVar v) a
@@ -580,6 +612,7 @@ resubscribeSMPSession c@AgentClient {smpSubWorkers} tSess =
       withRetryInterval ri $ \_ loop -> do
         pending <- atomically getPending
         forM_ (L.nonEmpty pending) $ \qs -> do
+          waitForUserNetwork c
           void . tryAgentError' $ reconnectSMPClient timeoutCounts c tSess qs
           loop
     getPending = RQ.getSessQueues tSess $ pendingSubs c
@@ -588,11 +621,11 @@ resubscribeSMPSession c@AgentClient {smpSubWorkers} tSess =
       -- Here we wait until TMVar is not empty to prevent worker cleanup happening before worker is added to TMVar.
       -- Not waiting may result in terminated worker remaining in the map.
       whenM (isEmptyTMVar $ sessionVar v) retry
-      removeTSessVar v tSess smpSubWorkers
+      removeSessVar v tSess smpSubWorkers
 
 reconnectSMPClient :: TVar Int -> AgentClient -> SMPTransportSession -> NonEmpty RcvQueue -> AM ()
 reconnectSMPClient tc c tSess@(_, srv, _) qs = do
-  NetworkConfig {tcpTimeout} <- readTVarIO $ useNetworkConfig c
+  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
@@ -622,9 +655,9 @@ reconnectSMPClient tc c tSess@(_, srv, _) qs = do
     notifySub connId cmd = atomically $ writeTBQueue (subQ c) ("", connId, APC (sAEntity @e) cmd)
 
 getNtfServerClient :: AgentClient -> NtfTransportSession -> AM NtfClient
-getNtfServerClient c@AgentClient {active, ntfClients} tSess@(userId, srv, _) = do
+getNtfServerClient c@AgentClient {active, ntfClients, workerSeq} tSess@(userId, srv, _) = do
   unlessM (readTVarIO active) . throwError $ INACTIVE
-  atomically (getTSessVar c tSess ntfClients)
+  atomically (getSessVar workerSeq tSess ntfClients)
     >>= either
       (newProtocolClient c tSess ntfClients connectClient)
       (waitForProtocolClient c tSess)
@@ -634,19 +667,20 @@ getNtfServerClient c@AgentClient {active, ntfClients} tSess@(userId, srv, _) = d
       cfg <- lift $ getClientConfig c ntfCfg
       g <- asks random
       liftError' (protocolClientError NTF $ B.unpack $ strEncode srv) $
-        getProtocolClient g tSess cfg Nothing $ clientDisconnected v
+        getProtocolClient g tSess cfg Nothing $
+          clientDisconnected v
 
     clientDisconnected :: NtfClientVar -> NtfClient -> IO ()
     clientDisconnected v client = do
-      atomically $ removeTSessVar v tSess ntfClients
+      atomically $ removeSessVar v tSess ntfClients
       incClientStat c userId client "DISCONNECT" ""
       atomically $ writeTBQueue (subQ c) ("", "", APC SAENone $ hostEvent DISCONNECT client)
       logInfo . decodeUtf8 $ "Agent disconnected from " <> showServer srv
 
 getXFTPServerClient :: AgentClient -> XFTPTransportSession -> AM XFTPClient
-getXFTPServerClient c@AgentClient {active, xftpClients, useNetworkConfig} tSess@(userId, srv, _) = do
+getXFTPServerClient c@AgentClient {active, xftpClients, workerSeq} tSess@(userId, srv, _) = do
   unlessM (readTVarIO active) . throwError $ INACTIVE
-  atomically (getTSessVar c tSess xftpClients)
+  atomically (getSessVar workerSeq tSess xftpClients)
     >>= either
       (newProtocolClient c tSess xftpClients connectClient)
       (waitForProtocolClient c tSess)
@@ -654,41 +688,21 @@ getXFTPServerClient c@AgentClient {active, xftpClients, useNetworkConfig} tSess@
     connectClient :: XFTPClientVar -> AM XFTPClient
     connectClient v = do
       cfg <- asks $ xftpCfg . config
-      xftpNetworkConfig <- readTVarIO useNetworkConfig
+      xftpNetworkConfig <- atomically $ getNetworkConfig c
       liftError' (protocolClientError XFTP $ B.unpack $ strEncode srv) $
-        X.getXFTPClient tSess cfg {xftpNetworkConfig} $ clientDisconnected v
+        X.getXFTPClient tSess cfg {xftpNetworkConfig} $
+          clientDisconnected v
 
     clientDisconnected :: XFTPClientVar -> XFTPClient -> IO ()
     clientDisconnected v client = do
-      atomically $ removeTSessVar v tSess xftpClients
+      atomically $ removeSessVar v tSess xftpClients
       incClientStat c userId client "DISCONNECT" ""
       atomically $ writeTBQueue (subQ c) ("", "", APC SAENone $ hostEvent DISCONNECT client)
       logInfo . decodeUtf8 $ "Agent disconnected from " <> showServer srv
 
-getTSessVar :: forall a s. AgentClient -> TransportSession s -> TMap (TransportSession s) (SessionVar a) -> STM (Either (SessionVar a) (SessionVar a))
-getTSessVar c tSess vs = maybe (Left <$> newSessionVar) (pure . Right) =<< TM.lookup tSess vs
-  where
-    newSessionVar :: STM (SessionVar a)
-    newSessionVar = do
-      sessionVar <- newEmptyTMVar
-      sessionVarId <- stateTVar (workerSeq c) $ \next -> (next, next + 1)
-      let v = SessionVar {sessionVar, sessionVarId}
-      TM.insert tSess v vs
-      pure v
-
-removeTSessVar :: SessionVar a -> TransportSession msg -> TMap (TransportSession msg) (SessionVar a) -> STM ()
-removeTSessVar = void .:. removeTSessVar'
-{-# INLINE removeTSessVar #-}
-
-removeTSessVar' :: SessionVar a -> TransportSession msg -> TMap (TransportSession msg) (SessionVar a) -> STM Bool
-removeTSessVar' v tSess vs =
-  TM.lookup tSess vs >>= \case
-    Just v' | sessionVarId v == sessionVarId v' -> TM.delete tSess vs $> True
-    _ -> pure False
-
 waitForProtocolClient :: ProtocolTypeI (ProtoType msg) => AgentClient -> TransportSession msg -> ClientVar msg -> AM (Client msg)
 waitForProtocolClient c (_, srv, _) v = do
-  NetworkConfig {tcpConnectTimeout} <- readTVarIO $ useNetworkConfig c
+  NetworkConfig {tcpConnectTimeout} <- atomically $ getNetworkConfig c
   client_ <- liftIO $ tcpConnectTimeout `timeout` atomically (readTMVar $ sessionVar v)
   liftEither $ case client_ of
     Just (Right smpClient) -> Right smpClient
@@ -716,7 +730,7 @@ newProtocolClient c tSess@(userId, srv, entityId_) clients connectClient v =
     Left e -> do
       liftIO $ incServerStat c userId srv "CLIENT" $ strEncode e
       atomically $ do
-        removeTSessVar v tSess clients
+        removeSessVar v tSess clients
         putTMVar (sessionVar v) (Left e)
       throwError e -- signal error to caller
 
@@ -724,11 +738,52 @@ hostEvent :: forall v err msg. (ProtocolTypeI (ProtoType msg), ProtocolServerCli
 hostEvent event = event (AProtocolType $ protocolTypeI @(ProtoType msg)) . clientTransportHost
 
 getClientConfig :: AgentClient -> (AgentConfig -> ProtocolClientConfig v) -> AM' (ProtocolClientConfig v)
-getClientConfig AgentClient {useNetworkConfig} cfgSel = do
+getClientConfig c cfgSel = do
   cfg <- asks $ cfgSel . config
-  networkConfig <- readTVarIO useNetworkConfig
+  networkConfig <- atomically $ getNetworkConfig c
   pure cfg {networkConfig}
 
+getNetworkConfig :: AgentClient -> STM NetworkConfig
+getNetworkConfig c = do
+  (slowCfg, fastCfg) <- readTVar (useNetworkConfig c)
+  UserNetworkState {networkType} <- readTVar (userNetworkState c)
+  pure $ case networkType of
+    UNCellular -> slowCfg
+    UNNone -> slowCfg
+    _ -> fastCfg
+
+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
   atomically $ writeTVar (active c) False
@@ -784,10 +839,11 @@ closeClient c clientSel tSess =
 
 closeClient_ :: ProtocolServerClient v err msg => AgentClient -> ClientVar msg -> IO ()
 closeClient_ c v = do
-  NetworkConfig {tcpConnectTimeout} <- readTVarIO $ useNetworkConfig c
-  tcpConnectTimeout `timeout` atomically (readTMVar $ sessionVar v) >>= \case
-    Just (Right client) -> closeProtocolServerClient client `catchAll_` pure ()
-    _ -> pure ()
+  NetworkConfig {tcpConnectTimeout} <- atomically $ getNetworkConfig c
+  E.handle (\BlockedIndefinitelyOnSTM -> pure ()) $
+    tcpConnectTimeout `timeout` atomically (readTMVar $ sessionVar v) >>= \case
+      Just (Right client) -> closeProtocolServerClient client `catchAll_` pure ()
+      _ -> pure ()
 
 closeXFTPServerClient :: AgentClient -> UserId -> XFTPServer -> FileDigest -> IO ()
 closeXFTPServerClient c userId server (FileDigest chunkDigest) =
@@ -799,7 +855,7 @@ withConnLock c connId name = ExceptT . withConnLock' c connId name . runExceptT
 
 withConnLock' :: AgentClient -> ConnId -> String -> AM' a -> AM' a
 withConnLock' _ "" _ = id
-withConnLock' AgentClient {connLocks} connId name = withLockMap_ connLocks connId name
+withConnLock' AgentClient {connLocks} connId name = withLockMap connLocks connId name
 {-# INLINE withConnLock' #-}
 
 withInvLock :: AgentClient -> ByteString -> String -> AM a -> AM a
@@ -807,16 +863,16 @@ withInvLock c key name = ExceptT . withInvLock' c key name . runExceptT
 {-# INLINE withInvLock #-}
 
 withInvLock' :: AgentClient -> ByteString -> String -> AM' a -> AM' a
-withInvLock' AgentClient {invLocks} = withLockMap_ invLocks
+withInvLock' AgentClient {invLocks} = withLockMap invLocks
 {-# INLINE withInvLock' #-}
 
 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_ #-}
+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 -> [k] -> String -> m a -> m a
 withLocksMap_ = withGetLocks . getMapLock
@@ -945,7 +1001,7 @@ runXFTPServerTest :: AgentClient -> UserId -> XFTPServerWithAuth -> AM' (Maybe P
 runXFTPServerTest c userId (ProtoServerWithAuth srv auth) = do
   cfg <- asks $ xftpCfg . config
   g <- asks random
-  xftpNetworkConfig <- readTVarIO $ useNetworkConfig c
+  xftpNetworkConfig <- atomically $ getNetworkConfig c
   workDir <- getXFTPWorkPath
   filePath <- getTempFilePath workDir
   rcvPath <- getTempFilePath workDir
@@ -1035,7 +1091,7 @@ mkSMPTSession q = mkTSession (qUserId q) (qServer q) (qConnId q)
 {-# INLINE mkSMPTSession #-}
 
 getSessionMode :: AgentClient -> IO TransportSessionMode
-getSessionMode = fmap sessionMode . readTVarIO . useNetworkConfig
+getSessionMode = atomically . fmap sessionMode . getNetworkConfig
 {-# INLINE getSessionMode #-}
 
 newRcvQueue :: AgentClient -> UserId -> ConnId -> SMPServerWithAuth -> VersionRangeSMPC -> SubscriptionMode -> AM (NewRcvQueue, SMPQueueUri)
@@ -1086,6 +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 #-}
@@ -1127,7 +1185,7 @@ sendTSessionBatches statCmd statBatchSize toRQ action c qs =
   where
     batchQueues :: AM' [(SMPTransportSession, NonEmpty q)]
     batchQueues = do
-      mode <- sessionMode <$> readTVarIO (useNetworkConfig c)
+      mode <- atomically $ sessionMode <$> getNetworkConfig c
       pure . M.assocs $ foldl' (batch mode) M.empty qs
       where
         batch mode m q =
@@ -1770,3 +1828,7 @@ $(J.deriveJSON defaultJSON ''WorkersSummary)
 $(J.deriveJSON defaultJSON {J.fieldLabelModifier = takeWhile (/= '_')} ''AgentWorkersDetails)
 
 $(J.deriveJSON defaultJSON ''AgentWorkersSummary)
+
+$(J.deriveJSON (enumJSON $ dropPrefix "UN") ''UserNetworkType)
+
+$(J.deriveJSON defaultJSON ''UserNetworkInfo)

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

@@ -92,6 +92,7 @@ data AgentConfig = AgentConfig
     xftpCfg :: XFTPClientConfig,
     reconnectInterval :: RetryInterval,
     messageRetryInterval :: RetryInterval2,
+    userNetworkInterval :: RetryInterval,
     messageTimeout :: NominalDiffTime,
     connDeleteDeliveryTimeout :: NominalDiffTime,
     helloTimeout :: NominalDiffTime,
@@ -126,7 +127,7 @@ defaultReconnectInterval =
   RetryInterval
     { initialInterval = 2_000000,
       increaseAfter = 10_000000,
-      maxInterval = 180_000000
+      maxInterval = 60_000000
     }
 
 defaultMessageRetryInterval :: RetryInterval2
@@ -134,18 +135,26 @@ defaultMessageRetryInterval =
   RetryInterval2
     { riFast =
         RetryInterval
-          { initialInterval = 1_000000,
+          { initialInterval = 2_000000,
             increaseAfter = 10_000000,
             maxInterval = 60_000000
           },
       riSlow =
         RetryInterval
-          { initialInterval = 180_000000, -- 3 minutes
+          { initialInterval = 300_000000, -- 5 minutes
             increaseAfter = 60_000000,
-            maxInterval = 3 * 3600_000000 -- 3 hours
+            maxInterval = 6 * 3600_000000 -- 6 hours
           }
     }
 
+defaultUserNetworkInterval :: RetryInterval
+defaultUserNetworkInterval =
+  RetryInterval
+    { initialInterval = 1200_000000, -- 20 minutes
+      increaseAfter = 0,
+      maxInterval = 7200_000000 -- 2 hours
+    }
+
 defaultAgentConfig :: AgentConfig
 defaultAgentConfig =
   AgentConfig
@@ -161,6 +170,7 @@ defaultAgentConfig =
       xftpCfg = defaultXFTPClientConfig,
       reconnectInterval = defaultReconnectInterval,
       messageRetryInterval = defaultMessageRetryInterval,
+      userNetworkInterval = defaultUserNetworkInterval,
       messageTimeout = 2 * nominalDay,
       connDeleteDeliveryTimeout = 2 * nominalDay,
       helloTimeout = 2 * nominalDay,

src/Simplex/Messaging/Agent/NtfSubSupervisor.hs

@@ -160,7 +160,8 @@ runNtfWorker c srv Worker {doWork} = do
         \nextSub@(NtfSubscription {connId}, _, _) -> do
           logInfo $ "runNtfWorker, nextSub " <> tshow nextSub
           ri <- asks $ reconnectInterval . config
-          withRetryInterval ri $ \_ loop ->
+          withRetryInterval ri $ \_ loop -> do
+            lift $ waitForUserNetwork c
             processSub nextSub
               `catchAgentError` retryOnError c "NtfWorker" loop (workerInternalError c connId . show)
     processSub :: (NtfSubscription, NtfSubNTFAction, NtfActionTs) -> AM ()
@@ -243,7 +244,8 @@ runNtfSMPWorker c srv Worker {doWork} = do
         \nextSub@(NtfSubscription {connId}, _, _) -> do
           logInfo $ "runNtfSMPWorker, nextSub " <> tshow nextSub
           ri <- asks $ reconnectInterval . config
-          withRetryInterval ri $ \_ loop ->
+          withRetryInterval ri $ \_ loop -> do
+            lift $ waitForUserNetwork c
             processSub nextSub
               `catchAgentError` retryOnError c "NtfSMPWorker" loop (workerInternalError c connId . show)
     processSub :: (NtfSubscription, NtfSubSMPAction, NtfActionTs) -> AM ()

src/Simplex/Messaging/Agent/Protocol.hs

@@ -163,6 +163,7 @@ import Data.Aeson (FromJSON (..), ToJSON (..))
 import qualified Data.Aeson.TH as J
 import Data.Attoparsec.ByteString.Char8 (Parser)
 import qualified Data.Attoparsec.ByteString.Char8 as A
+import Data.ByteString.Base64
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
 import Data.Functor (($>))
@@ -201,7 +202,6 @@ import Simplex.Messaging.Crypto.Ratchet
     SndE2ERatchetParams
   )
 import Simplex.Messaging.Encoding
-import Simplex.Messaging.Encoding.Base64 (base64P, encode)
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Parsers
 import Simplex.Messaging.Protocol
@@ -405,6 +405,7 @@ data ACommand (p :: AParty) (e :: AEntity) where
   MSGNTF :: SMPMsgMeta -> ACommand Agent AEConn
   ACK :: AgentMsgId -> Maybe MsgReceiptInfo -> ACommand Client AEConn
   RCVD :: MsgMeta -> NonEmpty MsgReceipt -> ACommand Agent AEConn
+  QCONT :: ACommand Agent AEConn
   SWCH :: ACommand Client AEConn
   OFF :: ACommand Client AEConn
   DEL :: ACommand Client AEConn
@@ -467,6 +468,7 @@ data ACommandTag (p :: AParty) (e :: AEntity) where
   MSGNTF_ :: ACommandTag Agent AEConn
   ACK_ :: ACommandTag Client AEConn
   RCVD_ :: ACommandTag Agent AEConn
+  QCONT_ :: ACommandTag Agent AEConn
   SWCH_ :: ACommandTag Client AEConn
   OFF_ :: ACommandTag Client AEConn
   DEL_ :: ACommandTag Client AEConn
@@ -522,6 +524,7 @@ aCommandTag = \case
   MSGNTF {} -> MSGNTF_
   ACK {} -> ACK_
   RCVD {} -> RCVD_
+  QCONT -> QCONT_
   SWCH -> SWCH_
   OFF -> OFF_
   DEL -> DEL_
@@ -996,7 +999,7 @@ agentMessageType = \case
     HELLO -> AM_HELLO_
     A_MSG _ -> AM_A_MSG_
     A_RCVD {} -> AM_A_RCVD_
-    QCONT _ -> AM_QCONT_
+    A_QCONT _ -> AM_QCONT_
     QADD _ -> AM_QADD_
     QKEY _ -> AM_QKEY_
     QUSE _ -> AM_QUSE_
@@ -1020,7 +1023,7 @@ data AMsgType
   = HELLO_
   | A_MSG_
   | A_RCVD_
-  | QCONT_
+  | A_QCONT_
   | QADD_
   | QKEY_
   | QUSE_
@@ -1033,7 +1036,7 @@ instance Encoding AMsgType where
     HELLO_ -> "H"
     A_MSG_ -> "M"
     A_RCVD_ -> "V"
-    QCONT_ -> "QC"
+    A_QCONT_ -> "QC"
     QADD_ -> "QA"
     QKEY_ -> "QK"
     QUSE_ -> "QU"
@@ -1046,7 +1049,7 @@ instance Encoding AMsgType where
       'V' -> pure A_RCVD_
       'Q' ->
         A.anyChar >>= \case
-          'C' -> pure QCONT_
+          'C' -> pure A_QCONT_
           'A' -> pure QADD_
           'K' -> pure QKEY_
           'U' -> pure QUSE_
@@ -1066,7 +1069,7 @@ data AMessage
   | -- | agent envelope for delivery receipt
     A_RCVD (NonEmpty AMessageReceipt)
   | -- | the message instructing the client to continue sending messages (after ERR QUOTA)
-    QCONT SndQAddr
+    A_QCONT SndQAddr
   | -- add queue to connection (sent by recipient), with optional address of the replaced queue
     QADD (NonEmpty (SMPQueueUri, Maybe SndQAddr))
   | -- key to secure the added queues and agree e2e encryption key (sent by sender)
@@ -1124,7 +1127,7 @@ instance Encoding AMessage where
     HELLO -> smpEncode HELLO_
     A_MSG body -> smpEncode (A_MSG_, Tail body)
     A_RCVD mrs -> smpEncode (A_RCVD_, mrs)
-    QCONT addr -> smpEncode (QCONT_, addr)
+    A_QCONT addr -> smpEncode (A_QCONT_, addr)
     QADD qs -> smpEncode (QADD_, qs)
     QKEY qs -> smpEncode (QKEY_, qs)
     QUSE qs -> smpEncode (QUSE_, qs)
@@ -1136,7 +1139,7 @@ instance Encoding AMessage where
         HELLO_ -> pure HELLO
         A_MSG_ -> A_MSG . unTail <$> smpP
         A_RCVD_ -> A_RCVD <$> smpP
-        QCONT_ -> QCONT <$> smpP
+        A_QCONT_ -> A_QCONT <$> smpP
         QADD_ -> QADD <$> smpP
         QKEY_ -> QKEY <$> smpP
         QUSE_ -> QUSE <$> smpP
@@ -1668,6 +1671,7 @@ instance StrEncoding ACmdTag where
       "MSGNTF" -> ct MSGNTF_
       "ACK" -> t ACK_
       "RCVD" -> ct RCVD_
+      "QCONT" -> ct QCONT_
       "SWCH" -> t SWCH_
       "OFF" -> t OFF_
       "DEL" -> t DEL_
@@ -1725,6 +1729,7 @@ instance (APartyI p, AEntityI e) => StrEncoding (ACommandTag p e) where
     MSGNTF_ -> "MSGNTF"
     ACK_ -> "ACK"
     RCVD_ -> "RCVD"
+    QCONT_ -> "QCONT"
     SWCH_ -> "SWCH"
     OFF_ -> "OFF"
     DEL_ -> "DEL"
@@ -1794,6 +1799,7 @@ commandP binaryP =
           MSG_ -> s (MSG <$> strP <* A.space <*> smpP <* A.space <*> binaryP)
           MSGNTF_ -> s (MSGNTF <$> strP)
           RCVD_ -> s (RCVD <$> strP <* A.space <*> strP)
+          QCONT_ -> pure QCONT
           DEL_RCVQ_ -> s (DEL_RCVQ <$> strP_ <*> strP_ <*> strP)
           DEL_CONN_ -> pure DEL_CONN
           DEL_USER_ -> s (DEL_USER <$> strP)
@@ -1857,6 +1863,7 @@ serializeCommand = \case
   MSGNTF smpMsgMeta -> s (MSGNTF_, smpMsgMeta)
   ACK mId rcptInfo_ -> s (ACK_, mId) <> maybe "" (B.cons ' ' . serializeBinary) rcptInfo_
   RCVD msgMeta rcpts -> s (RCVD_, msgMeta, rcpts)
+  QCONT -> s QCONT_
   SWCH -> s SWCH_
   OFF -> s OFF_
   DEL -> s DEL_

src/Simplex/Messaging/Agent/RetryInterval.hs

@@ -11,6 +11,7 @@ module Simplex.Messaging.Agent.RetryInterval
     withRetryIntervalCount,
     withRetryLock2,
     updateRetryInterval2,
+    nextRetryDelay,
   )
 where
 
@@ -60,7 +61,7 @@ withRetryIntervalCount ri action = callAction 0 0 $ initialInterval ri
         loop = do
           liftIO $ threadDelay' delay
           let elapsed' = elapsed + delay
-          callAction (n + 1) elapsed' $ nextDelay elapsed' delay ri
+          callAction (n + 1) elapsed' $ nextRetryDelay elapsed' delay ri
 
 -- This function allows action to toggle between slow and fast retry intervals.
 withRetryLock2 :: forall m. MonadIO m => RetryInterval2 -> TMVar () -> (RI2State -> (RetryIntervalMode -> m ()) -> m ()) -> m ()
@@ -76,7 +77,7 @@ withRetryLock2 RetryInterval2 {riSlow, riFast} lock action =
         run (elapsed, delay) ri call = do
           wait delay
           let elapsed' = elapsed + delay
-              delay' = nextDelay elapsed' delay ri
+              delay' = nextRetryDelay elapsed' delay ri
           call (elapsed', delay')
         wait delay = do
           waiting <- newTVarIO True
@@ -87,8 +88,8 @@ withRetryLock2 RetryInterval2 {riSlow, riFast} lock action =
             takeTMVar lock
             writeTVar waiting False
 
-nextDelay :: Int64 -> Int64 -> RetryInterval -> Int64
-nextDelay elapsed delay RetryInterval {increaseAfter, maxInterval} =
+nextRetryDelay :: Int64 -> Int64 -> RetryInterval -> Int64
+nextRetryDelay elapsed delay RetryInterval {increaseAfter, maxInterval} =
   if elapsed < increaseAfter || delay == maxInterval
     then delay
     else min (delay * 3 `div` 2) maxInterval

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

@@ -231,6 +231,7 @@ import Data.Bifunctor (first, second)
 import Data.ByteArray (ScrubbedBytes)
 import qualified Data.ByteArray as BA
 import Data.ByteString (ByteString)
+import qualified Data.ByteString.Base64.URL as U
 import qualified Data.ByteString.Char8 as B
 import Data.Char (toLower)
 import Data.Functor (($>))
@@ -270,7 +271,6 @@ import Simplex.Messaging.Crypto.File (CryptoFile (..), CryptoFileArgs (..))
 import Simplex.Messaging.Crypto.Ratchet (RatchetX448, SkippedMsgDiff (..), SkippedMsgKeys, PQEncryption (..), PQSupport (..))
 import qualified Simplex.Messaging.Crypto.Ratchet as CR
 import Simplex.Messaging.Encoding
-import qualified Simplex.Messaging.Encoding.Base64.URL as U
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Notifications.Protocol (DeviceToken (..), NtfSubscriptionId, NtfTknStatus (..), NtfTokenId, SMPQueueNtf (..))
 import Simplex.Messaging.Notifications.Types
@@ -1214,7 +1214,7 @@ setRatchetX3dhKeys db connId x3dhPrivKey1 x3dhPrivKey2 pqPrivKem =
     db
     [sql|
       UPDATE ratchets
-      SET x3dh_priv_key_1 = ?, x3dh_priv_key_2 = ?, x3dh_pub_key_1 = ?, x3dh_pub_key_2 = ?, pq_priv_kem = ? 
+      SET x3dh_priv_key_1 = ?, x3dh_priv_key_2 = ?, x3dh_pub_key_1 = ?, x3dh_pub_key_2 = ?, pq_priv_kem = ?
       WHERE conn_id = ?
     |]
     (x3dhPrivKey1, x3dhPrivKey2, C.publicKey x3dhPrivKey1, C.publicKey x3dhPrivKey2, pqPrivKem, connId)

src/Simplex/Messaging/Client.hs

@@ -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,
 
@@ -84,8 +88,8 @@ import Control.Concurrent.Async
 import Control.Concurrent.STM
 import Control.Exception
 import Control.Monad
-import Control.Monad.IO.Class (liftIO)
 import Control.Monad.Except
+import Control.Monad.IO.Class (liftIO)
 import Control.Monad.Trans.Except
 import Crypto.Random (ChaChaDRG)
 import qualified Data.Aeson.TH as J
@@ -98,9 +102,12 @@ import Data.List.NonEmpty (NonEmpty (..))
 import qualified Data.List.NonEmpty as L
 import Data.Maybe (fromMaybe)
 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
@@ -110,7 +117,7 @@ import Simplex.Messaging.Transport
 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, raceAny_, threadDelay')
+import Simplex.Messaging.Util (bshow, liftEitherWith, raceAny_, threadDelay')
 import Simplex.Messaging.Version
 import System.Timeout (timeout)
 
@@ -119,7 +126,7 @@ import System.Timeout (timeout)
 -- Use 'getSMPClient' to connect to an SMP server and create a client handle.
 data ProtocolClient v err msg = ProtocolClient
   { action :: Maybe (Async ()),
-    thParams :: THandleParams v,
+    thParams :: THandleParams v 'TClient,
     sessionTs :: UTCTime,
     client_ :: PClient v err msg
   }
@@ -129,7 +136,6 @@ data PClient v err msg = PClient
     transportSession :: TransportSession msg,
     transportHost :: TransportHost,
     tcpTimeout :: Int,
-    batchDelay :: Maybe Int,
     pingErrorCount :: TVar Int,
     clientCorrId :: TVar ChaChaDRG,
     sentCommands :: TMap CorrId (Request err msg),
@@ -138,7 +144,7 @@ data PClient v err msg = PClient
     msgQ :: Maybe (TBQueue (ServerTransmission v msg))
   }
 
-smpClientStub :: TVar ChaChaDRG -> ByteString -> VersionSMP -> Maybe THandleAuth -> STM SMPClient
+smpClientStub :: TVar ChaChaDRG -> ByteString -> VersionSMP -> Maybe (THandleAuth 'TClient) -> STM SMPClient
 smpClientStub g sessionId thVersion thAuth = do
   connected <- newTVar False
   clientCorrId <- C.newRandomDRG g
@@ -165,7 +171,6 @@ smpClientStub g sessionId thVersion thAuth = do
               transportSession = (1, "smp://LcJUMfVhwD8yxjAiSaDzzGF3-kLG4Uh0Fl_ZIjrRwjI=@localhost:5001", Nothing),
               transportHost = "localhost",
               tcpTimeout = 15_000_000,
-              batchDelay = Nothing,
               pingErrorCount,
               clientCorrId,
               sentCommands,
@@ -207,7 +212,7 @@ data NetworkConfig = NetworkConfig
     -- | timeout of protocol commands (microseconds)
     tcpTimeout :: Int,
     -- | additional timeout per kilobyte (1024 bytes) to be sent
-    tcpTimeoutPerKb :: Int,
+    tcpTimeoutPerKb :: Int64,
     -- | TCP keep-alive options, Nothing to skip enabling keep-alive
     tcpKeepAlive :: Maybe KeepAliveOpts,
     -- | period for SMP ping commands (microseconds, 0 to disable)
@@ -230,7 +235,7 @@ defaultNetworkConfig =
       sessionMode = TSMUser,
       tcpConnectTimeout = 20_000_000,
       tcpTimeout = 15_000_000,
-      tcpTimeoutPerKb = 45_000, -- 45ms, should be less than 130ms to avoid Int overflow on 32 bit systems
+      tcpTimeoutPerKb = 5_000,
       tcpKeepAlive = Just defaultKeepAliveOpts,
       smpPingInterval = 600_000_000, -- 10min
       smpPingCount = 3,
@@ -239,7 +244,7 @@ defaultNetworkConfig =
 
 transportClientConfig :: NetworkConfig -> TransportClientConfig
 transportClientConfig NetworkConfig {socksProxy, tcpKeepAlive, logTLSErrors} =
-  TransportClientConfig {socksProxy, tcpKeepAlive, logTLSErrors, clientCredentials = Nothing}
+  TransportClientConfig {socksProxy, tcpKeepAlive, logTLSErrors, clientCredentials = Nothing, alpn = Nothing}
 {-# INLINE transportClientConfig #-}
 
 -- | protocol client configuration.
@@ -252,8 +257,8 @@ data ProtocolClientConfig v = ProtocolClientConfig
     networkConfig :: NetworkConfig,
     -- | client-server protocol version range
     serverVRange :: VersionRange v,
-    -- | delay between sending batches of commands (microseconds)
-    batchDelay :: Maybe Int
+    -- | agree shared session secret (used in SMP proxy)
+    agreeSecret :: Bool
   }
 
 -- | Default protocol client configuration.
@@ -264,7 +269,7 @@ defaultClientConfig serverVRange =
       defaultTransport = ("443", transport @TLS),
       networkConfig = defaultNetworkConfig,
       serverVRange,
-      batchDelay = Nothing
+      agreeSecret = False
     }
 {-# INLINE defaultClientConfig #-}
 
@@ -321,7 +326,7 @@ 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, serverVRange, batchDelay} msgQ disconnected = do
+getProtocolClient g transportSession@(_, srv, _) cfg@ProtocolClientConfig {qSize, networkConfig, serverVRange, agreeSecret} msgQ disconnected = do
   case chooseTransportHost networkConfig (host srv) of
     Right useHost ->
       (atomically (mkProtocolClient useHost) >>= runClient useTransport useHost)
@@ -343,7 +348,6 @@ getProtocolClient g transportSession@(_, srv, _) cfg@ProtocolClientConfig {qSize
             transportSession,
             transportHost,
             tcpTimeout,
-            batchDelay,
             pingErrorCount,
             clientCorrId,
             sentCommands,
@@ -375,7 +379,7 @@ getProtocolClient g transportSession@(_, srv, _) cfg@ProtocolClientConfig {qSize
 
     client :: forall c. Transport c => TProxy c -> PClient v err msg -> TMVar (Either (ProtocolClientError err) (ProtocolClient v err msg)) -> c -> IO ()
     client _ c cVar h = do
-      ks <- atomically $ C.generateKeyPair g
+      ks <- if agreeSecret then Just <$> atomically (C.generateKeyPair g) else pure Nothing
       runExceptT (protocolClientHandshake @v @err @msg h ks (keyHash srv) serverVRange) >>= \case
         Left e -> atomically . putTMVar cVar . Left $ PCETransportError e
         Right th@THandle {params} -> do
@@ -387,10 +391,10 @@ getProtocolClient g transportSession@(_, srv, _) cfg@ProtocolClientConfig {qSize
           raceAny_ ([send c' th, process c', receive c' th] <> [ping c' | smpPingInterval > 0])
             `finally` disconnected c'
 
-    send :: Transport c => ProtocolClient v err msg -> THandle v c -> IO ()
+    send :: Transport c => ProtocolClient v err msg -> THandle v c 'TClient -> IO ()
     send ProtocolClient {client_ = PClient {sndQ}} h = forever $ atomically (readTBQueue sndQ) >>= tPutLog h
 
-    receive :: Transport c => ProtocolClient v err msg -> THandle v c -> IO ()
+    receive :: Transport c => ProtocolClient v err msg -> THandle v c 'TClient -> IO ()
     receive ProtocolClient {client_ = PClient {rcvQ}} h = forever $ tGet h >>= atomically . writeTBQueue rcvQ
 
     ping :: ProtocolClient v err msg -> IO ()
@@ -480,6 +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
@@ -630,6 +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
@@ -693,8 +805,11 @@ sendBatch c@ProtocolClient {client_ = PClient {sndQ}} b = do
 
 -- | 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)
@@ -713,33 +828,35 @@ getResponse :: ProtocolClient v err msg -> Request err msg -> IO (Response err m
 getResponse ProtocolClient {client_ = PClient {tcpTimeout, pingErrorCount}} Request {entityId, responseVar} = do
   response <-
     timeout tcpTimeout (atomically (takeTMVar responseVar)) >>= \case
+      -- 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 entId <$> newEmptyTMVar
       TM.insert corrId r sentCommands
       pure r
 
-authTransmission :: Maybe THandleAuth -> 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 THandleAuth {peerPubKey} -> Right $ TAAuthenticator $ C.cbAuthenticate peerPubKey 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

src/Simplex/Messaging/Client/Agent.hs

@@ -40,6 +40,7 @@ import Simplex.Messaging.Client
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol (BrokerMsg, NotifierId, NtfPrivateAuthKey, ProtocolServer (..), QueueId, RcvPrivateAuthKey, RecipientId, SMPServer)
+import Simplex.Messaging.Session
 import Simplex.Messaging.TMap (TMap)
 import qualified Simplex.Messaging.TMap as TM
 import Simplex.Messaging.Transport
@@ -50,7 +51,7 @@ import UnliftIO.Exception (Exception)
 import qualified UnliftIO.Exception as E
 import UnliftIO.STM
 
-type SMPClientVar = TMVar (Either SMPClientError SMPClient)
+type SMPClientVar = SessionVar (Either SMPClientError SMPClient)
 
 data SMPClientAgentEvent
   = CAConnected SMPServer
@@ -97,10 +98,12 @@ 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 ()],
-    asyncClients :: TVar [Async ()]
+    asyncClients :: TVar [Async ()],
+    workerSeq :: TVar Int
   }
 
 newtype InternalException e = InternalException {unInternalException :: e}
@@ -115,9 +118,10 @@ instance Exception e => MonadUnliftIO (ExceptT e IO) where
     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
+
+-- 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 #-}
@@ -132,50 +136,61 @@ newSMPClientAgent agentCfg@SMPClientAgentConfig {msgQSize, agentQSize} randomDrg
   msgQ <- newTBQueue msgQSize
   agentQ <- newTBQueue agentQSize
   smpClients <- TM.empty
+  smpSessions <- TM.empty
   srvSubs <- TM.empty
   pendingSrvSubs <- TM.empty
   reconnections <- newTVar []
   asyncClients <- newTVar []
-  pure SMPClientAgent {agentCfg, msgQ, agentQ, randomDrg, smpClients, srvSubs, pendingSrvSubs, reconnections, asyncClients}
+  workerSeq <- newTVar 0
+  pure
+    SMPClientAgent
+      { agentCfg,
+        msgQ,
+        agentQ,
+        randomDrg,
+        smpClients,
+        smpSessions,
+        srvSubs,
+        pendingSrvSubs,
+        reconnections,
+        asyncClients,
+        workerSeq
+      }
 
 getSMPServerClient' :: SMPClientAgent -> SMPServer -> ExceptT SMPClientError IO SMPClient
-getSMPServerClient' ca@SMPClientAgent {agentCfg, smpClients, msgQ, randomDrg} srv =
+getSMPServerClient' ca@SMPClientAgent {agentCfg, smpClients, smpSessions, msgQ, randomDrg, workerSeq} srv =
   atomically getClientVar >>= either newSMPClient waitForSMPClient
   where
     getClientVar :: STM (Either SMPClientVar SMPClientVar)
-    getClientVar = maybe (Left <$> newClientVar) (pure . Right) =<< TM.lookup srv smpClients
-
-    newClientVar :: STM SMPClientVar
-    newClientVar = do
-      smpVar <- newEmptyTMVar
-      TM.insert srv smpVar smpClients
-      pure smpVar
+    getClientVar = getSessVar workerSeq srv smpClients
 
     waitForSMPClient :: SMPClientVar -> ExceptT SMPClientError IO SMPClient
-    waitForSMPClient smpVar = do
+    waitForSMPClient v = do
       let ProtocolClientConfig {networkConfig = NetworkConfig {tcpConnectTimeout}} = smpCfg agentCfg
-      smpClient_ <- liftIO $ tcpConnectTimeout `timeout` atomically (readTMVar smpVar)
+      smpClient_ <- liftIO $ tcpConnectTimeout `timeout` atomically (readTMVar $ sessionVar v)
       liftEither $ case smpClient_ of
         Just (Right smpClient) -> Right smpClient
         Just (Left e) -> Left e
         Nothing -> Left PCEResponseTimeout
 
     newSMPClient :: SMPClientVar -> ExceptT SMPClientError IO SMPClient
-    newSMPClient smpVar = tryConnectClient pure (liftIO tryConnectAsync)
+    newSMPClient v = tryConnectClient pure (liftIO tryConnectAsync)
       where
         tryConnectClient :: (SMPClient -> ExceptT SMPClientError IO a) -> ExceptT SMPClientError IO () -> ExceptT SMPClientError IO a
         tryConnectClient successAction retryAction =
-          tryE connectClient >>= \r -> case r of
+          tryE (connectClient v) >>= \r -> case r of
             Right smp -> do
               logInfo . decodeUtf8 $ "Agent connected to " <> showServer srv
-              atomically $ putTMVar smpVar r
+              atomically $ do
+                putTMVar (sessionVar v) r
+                TM.insert (sessionId $ thParams smp) smp smpSessions
               successAction smp
             Left e -> do
               if e == PCENetworkError || e == PCEResponseTimeout
                 then retryAction
                 else atomically $ do
-                  putTMVar smpVar (Left e)
-                  TM.delete srv smpClients
+                  putTMVar (sessionVar v) (Left e)
+                  removeSessVar v srv smpClients
               throwE e
         tryConnectAsync :: IO ()
         tryConnectAsync = do
@@ -186,17 +201,18 @@ getSMPServerClient' ca@SMPClientAgent {agentCfg, smpClients, msgQ, randomDrg} sr
           withRetryInterval (reconnectInterval agentCfg) $ \_ loop ->
             void $ tryConnectClient (const reconnectClient) loop
 
-    connectClient :: ExceptT SMPClientError IO SMPClient
-    connectClient = ExceptT $ getProtocolClient randomDrg (1, srv, Nothing) (smpCfg agentCfg) (Just msgQ) clientDisconnected
+    connectClient :: SMPClientVar -> ExceptT SMPClientError IO SMPClient
+    connectClient v = ExceptT $ getProtocolClient randomDrg (1, srv, Nothing) (smpCfg agentCfg) (Just msgQ) (clientDisconnected v)
 
-    clientDisconnected :: SMPClient -> IO ()
-    clientDisconnected _ = do
-      removeClientAndSubs >>= (`forM_` serverDown)
+    clientDisconnected :: SMPClientVar -> SMPClient -> IO ()
+    clientDisconnected v smp = do
+      removeClientAndSubs v smp >>= (`forM_` serverDown)
       logInfo . decodeUtf8 $ "Agent disconnected from " <> showServer srv
 
-    removeClientAndSubs :: IO (Maybe (Map SMPSub C.APrivateAuthKey))
-    removeClientAndSubs = atomically $ do
-      TM.delete srv smpClients
+    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
@@ -207,7 +223,7 @@ getSMPServerClient' ca@SMPClientAgent {agentCfg, smpClients, msgQ, randomDrg} sr
         addPendingSubs sVar ss = do
           let ps = pendingSrvSubs ca
           TM.lookup srv ps >>= \case
-            Just v -> TM.union ss v
+            Just ss' -> TM.union ss ss'
             _ -> TM.insert srv sVar ps
 
     serverDown :: Map SMPSub C.APrivateAuthKey -> IO ()
@@ -261,6 +277,9 @@ getSMPServerClient' ca@SMPClientAgent {agentCfg, smpClients, msgQ, randomDrg} sr
     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
@@ -268,10 +287,10 @@ closeSMPClientAgent c = do
   cancelActions $ asyncClients c
 
 closeSMPServerClients :: SMPClientAgent -> IO ()
-closeSMPServerClients c = readTVarIO (smpClients c) >>= mapM_ (forkIO . closeClient)
+closeSMPServerClients c = atomically (smpClients c `swapTVar` M.empty) >>= mapM_ (forkIO . closeClient)
   where
-    closeClient smpVar =
-      atomically (readTMVar smpVar) >>= \case
+    closeClient v =
+      atomically (readTMVar $ sessionVar v) >>= \case
         Right smp -> closeProtocolClient smp `catchAll_` pure ()
         _ -> pure ()
 

src/Simplex/Messaging/Crypto.hs

@@ -141,6 +141,7 @@ module Simplex.Messaging.Crypto
     sbEncrypt_,
     cbNonce,
     randomCbNonce,
+    reverseNonce,
 
     -- * NaCl crypto_secretbox
     SbKey (unSbKey),
@@ -211,6 +212,8 @@ import qualified Data.Attoparsec.ByteString.Char8 as A
 import Data.Bifunctor (bimap, first)
 import Data.ByteArray (ByteArrayAccess)
 import qualified Data.ByteArray as BA
+import Data.ByteString.Base64 (decode, encode)
+import qualified Data.ByteString.Base64.URL as U
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
 import Data.ByteString.Lazy (fromStrict, toStrict)
@@ -228,8 +231,6 @@ import Database.SQLite.Simple.ToField (ToField (..))
 import GHC.TypeLits (ErrorMessage (..), KnownNat, Nat, TypeError, natVal, type (+))
 import Network.Transport.Internal (decodeWord16, encodeWord16)
 import Simplex.Messaging.Encoding
-import Simplex.Messaging.Encoding.Base64 (decode, encode)
-import qualified Simplex.Messaging.Encoding.Base64.URL as U
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Parsers (blobFieldDecoder, parseAll, parseString)
 import Simplex.Messaging.Util ((<$?>))
@@ -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

src/Simplex/Messaging/Encoding/Base64.hs

@@ -1,29 +0,0 @@
-{-# LANGUAGE OverloadedStrings #-}
-
--- | Compatibility wrappers for base64 package, Base64 (padded) variant.
-module Simplex.Messaging.Encoding.Base64 where
-
-import qualified Data.Attoparsec.ByteString.Char8 as A
-import Data.Base64.Types (extractBase64)
-import Data.Bifunctor (first)
-import Data.ByteString.Base64 (decodeBase64Untyped, encodeBase64')
-import Data.ByteString.Char8 (ByteString)
-import qualified Data.ByteString.Char8 as B
-import qualified Data.Text as T
-
-encode :: ByteString -> ByteString
-encode = extractBase64 . encodeBase64'
-{-# INLINE encode #-}
-
-decode :: ByteString -> Either String ByteString
-decode = first T.unpack . decodeBase64Untyped
-{-# INLINE decode #-}
-
-base64P :: A.Parser ByteString
-base64P = do
-  str <- A.takeWhile1 (`B.elem` base64Alphabet)
-  pad <- A.takeWhile (== '=') -- correct amount of padding can be derived from str length
-  either (fail . T.unpack) pure $ decodeBase64Untyped (str <> pad)
-
-base64Alphabet :: ByteString
-base64Alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"

src/Simplex/Messaging/Encoding/Base64/URL.hs

@@ -1,33 +0,0 @@
-{-# LANGUAGE OverloadedStrings #-}
-
--- | Compatibility wrappers for base64 package, Base64URL-padded variant.
-module Simplex.Messaging.Encoding.Base64.URL where
-
-import qualified Data.Attoparsec.ByteString.Char8 as A
-import Data.Base64.Types (extractBase64)
-import Data.Bifunctor (first)
-import Data.ByteString.Base64.URL (decodeBase64Lenient, decodeBase64UnpaddedUntyped, decodeBase64Untyped, encodeBase64')
-import Data.ByteString.Char8 (ByteString)
-import qualified Data.ByteString.Char8 as B
-import qualified Data.Text as T
-
-encode :: ByteString -> ByteString
-encode = extractBase64 . encodeBase64'
-{-# INLINE encode #-}
-
-decode :: ByteString -> Either String ByteString
-decode = first T.unpack . decodeBase64Untyped
-{-# INLINE decode #-}
-
-decodeLenient :: ByteString -> ByteString
-decodeLenient = decodeBase64Lenient
-{-# INLINE decodeLenient #-}
-
-base64urlP :: A.Parser ByteString
-base64urlP = do
-  str <- A.takeWhile1 (`B.elem` base64AlphabetURL)
-  _pad <- A.takeWhile (== '=') -- correct amount of padding can be derived from str length
-  either (fail . T.unpack) pure $ decodeBase64UnpaddedUntyped str
-
-base64AlphabetURL :: ByteString
-base64AlphabetURL = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_"

src/Simplex/Messaging/Encoding/String.hs

@@ -10,6 +10,7 @@ module Simplex.Messaging.Encoding.String
     strToJSON,
     strToJEncoding,
     strParseJSON,
+    base64urlP,
     strEncodeList,
     strListP,
   )
@@ -22,8 +23,10 @@ import qualified Data.Aeson.Encoding as JE
 import qualified Data.Aeson.Types as JT
 import Data.Attoparsec.ByteString.Char8 (Parser)
 import qualified Data.Attoparsec.ByteString.Char8 as A
+import qualified Data.ByteString.Base64.URL as U
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
+import Data.Char (isAlphaNum)
 import Data.Int (Int64)
 import qualified Data.List.NonEmpty as L
 import Data.Set (Set)
@@ -35,7 +38,6 @@ import Data.Time.Clock.System (SystemTime (..))
 import Data.Time.Format.ISO8601
 import Data.Word (Word16, Word32)
 import Simplex.Messaging.Encoding
-import qualified Simplex.Messaging.Encoding.Base64.URL as U
 import Simplex.Messaging.Parsers (parseAll)
 import Simplex.Messaging.Util ((<$?>))
 
@@ -52,16 +54,19 @@ class StrEncoding a where
   strDecode :: ByteString -> Either String a
   strDecode = parseAll strP
   strP :: Parser a
-  strP = strDecode <$?> U.base64urlP
+  strP = strDecode <$?> base64urlP
 
 -- base64url encoding/decoding of ByteStrings - the parser only allows non-empty strings
 instance StrEncoding ByteString where
   strEncode = U.encode
-  {-# INLINE strEncode #-}
   strDecode = U.decode
-  {-# INLINE strDecode #-}
-  strP = U.base64urlP
-  {-# INLINE strP #-}
+  strP = base64urlP
+
+base64urlP :: Parser ByteString
+base64urlP = do
+  str <- A.takeWhile1 (\c -> isAlphaNum c || c == '-' || c == '_')
+  pad <- A.takeWhile (== '=')
+  either fail pure $ U.decode (str <> pad)
 
 newtype Str = Str {unStr :: ByteString}
   deriving (Eq, Show)
@@ -70,6 +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

src/Simplex/Messaging/Notifications/Protocol.hs

@@ -11,12 +11,14 @@
 
 module Simplex.Messaging.Notifications.Protocol where
 
+import Control.Applicative ((<|>))
 import Data.Aeson (FromJSON (..), ToJSON (..), (.:), (.=))
 import qualified Data.Aeson as J
 import qualified Data.Aeson.Encoding as JE
 import qualified Data.Attoparsec.ByteString.Char8 as A
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
+import Data.Functor (($>))
 import Data.Kind
 import Data.Maybe (isNothing)
 import Data.Text.Encoding (decodeLatin1, encodeUtf8)
@@ -150,7 +152,7 @@ instance Encoding ANewNtfEntity where
 instance Protocol NTFVersion ErrorType NtfResponse where
   type ProtoCommand NtfResponse = NtfCmd
   type ProtoType NtfResponse = 'PNTF
-  protocolClientHandshake = ntfClientHandshake
+  protocolClientHandshake c _ks = ntfClientHandshake c
   protocolPing = NtfCmd SSubscription PING
   protocolError = \case
     NRErr e -> Just e
@@ -406,10 +408,12 @@ instance Encoding DeviceToken where
 
 instance StrEncoding DeviceToken where
   strEncode (DeviceToken p t) = strEncode p <> " " <> t
-  strP = DeviceToken <$> strP <* A.space <*> hexStringP
+  strP = nullToken <|> hexToken
     where
+      nullToken = "apns_null test_ntf_token" $> DeviceToken PPApnsNull "test_ntf_token"
+      hexToken = DeviceToken <$> strP <* A.space <*> hexStringP
       hexStringP =
-        A.takeWhile (\c -> A.isDigit c || (c >= 'a' && c <= 'f')) >>= \s ->
+        A.takeWhile (`B.elem` "0123456789abcdef") >>= \s ->
           if even (B.length s) then pure s else fail "odd number of hex characters"
 
 instance ToJSON DeviceToken where

src/Simplex/Messaging/Notifications/Server.hs

@@ -47,7 +47,7 @@ import qualified Simplex.Messaging.Protocol as SMP
 import Simplex.Messaging.Server
 import Simplex.Messaging.Server.Stats
 import qualified Simplex.Messaging.TMap as TM
-import Simplex.Messaging.Transport (ATransport (..), THandle (..), THandleAuth (..), THandleParams (..), TProxy, Transport (..))
+import Simplex.Messaging.Transport (ATransport (..), THandle (..), THandleAuth (..), THandleParams (..), TProxy, Transport (..), TransportPeer (..))
 import Simplex.Messaging.Transport.Server (runTransportServer, tlsServerCredentials)
 import Simplex.Messaging.Util
 import System.Exit (exitFailure)
@@ -108,7 +108,7 @@ ntfServer cfg@NtfServerConfig {transports, transportConfig = tCfg} started = do
     logServerStats :: Int64 -> Int64 -> FilePath -> M ()
     logServerStats startAt logInterval statsFilePath = do
       initialDelay <- (startAt -) . fromIntegral . (`div` 1000000_000000) . diffTimeToPicoseconds . utctDayTime <$> liftIO getCurrentTime
-      liftIO $ putStrLn $ "server stats log enabled: " <> statsFilePath
+      logInfo $ "server stats log enabled: " <> T.pack statsFilePath
       liftIO $ threadDelay' $ 1000000 * (initialDelay + if initialDelay < 0 then 86400 else 0)
       NtfServerStats {fromTime, tknCreated, tknVerified, tknDeleted, subCreated, subDeleted, ntfReceived, ntfDelivered, activeTokens, activeSubs} <- asks serverStats
       let interval = 1000000 * logInterval
@@ -339,7 +339,7 @@ updateTknStatus NtfTknData {ntfTknId, tknStatus} status = do
   old <- atomically $ stateTVar tknStatus (,status)
   when (old /= status) $ withNtfLog $ \sl -> logTokenStatus sl ntfTknId status
 
-runNtfClientTransport :: Transport c => THandleNTF c -> M ()
+runNtfClientTransport :: Transport c => THandleNTF c 'TServer -> M ()
 runNtfClientTransport th@THandle {params} = do
   qSize <- asks $ clientQSize . config
   ts <- liftIO getSystemTime
@@ -356,7 +356,7 @@ runNtfClientTransport th@THandle {params} = do
 clientDisconnected :: NtfServerClient -> IO ()
 clientDisconnected NtfServerClient {connected} = atomically $ writeTVar connected False
 
-receive :: Transport c => THandleNTF c -> NtfServerClient -> M ()
+receive :: Transport c => THandleNTF c 'TServer -> NtfServerClient -> M ()
 receive th@THandle {params = THandleParams {thAuth}} NtfServerClient {rcvQ, sndQ, rcvActiveAt} = forever $ do
   ts <- liftIO $ tGet th
   forM_ ts $ \t@(_, _, (corrId, entId, cmdOrError)) -> do
@@ -371,7 +371,7 @@ receive th@THandle {params = THandleParams {thAuth}} NtfServerClient {rcvQ, sndQ
   where
     write q t = atomically $ writeTBQueue q t
 
-send :: Transport c => THandleNTF c -> NtfServerClient -> IO ()
+send :: Transport c => THandleNTF c 'TServer -> NtfServerClient -> IO ()
 send h@THandle {params} NtfServerClient {sndQ, sndActiveAt} = forever $ do
   t <- atomically $ readTBQueue sndQ
   void . liftIO $ tPut h [Right (Nothing, encodeTransmission params t)]
@@ -382,7 +382,7 @@ send h@THandle {params} NtfServerClient {sndQ, sndActiveAt} = forever $ do
 
 data VerificationResult = VRVerified NtfRequest | VRFailed
 
-verifyNtfTransmission :: Maybe (THandleAuth, C.CbNonce) -> SignedTransmission ErrorType NtfCmd -> NtfCmd -> M VerificationResult
+verifyNtfTransmission :: Maybe (THandleAuth 'TServer, C.CbNonce) -> SignedTransmission ErrorType NtfCmd -> NtfCmd -> M VerificationResult
 verifyNtfTransmission auth_ (tAuth, authorized, (corrId, entId, _)) cmd = do
   st <- asks store
   case cmd of
@@ -442,7 +442,7 @@ client NtfServerClient {rcvQ, sndQ} NtfSubscriber {newSubQ, smpAgent = ca} NtfPu
   where
     processCommand :: NtfRequest -> M (Transmission NtfResponse)
     processCommand = \case
-      NtfReqNew corrId (ANE SToken newTkn@(NewNtfTkn _ _ dhPubKey)) -> do
+      NtfReqNew corrId (ANE SToken newTkn@(NewNtfTkn token _ dhPubKey)) -> do
         logDebug "TNEW - new token"
         st <- asks store
         ks@(srvDhPubKey, srvDhPrivKey) <- atomically . C.generateKeyPair =<< asks random
@@ -453,9 +453,9 @@ client NtfServerClient {rcvQ, sndQ} NtfSubscriber {newSubQ, smpAgent = ca} NtfPu
         atomically $ addNtfToken st tknId tkn
         atomically $ writeTBQueue pushQ (tkn, PNVerification regCode)
         withNtfLog (`logCreateToken` tkn)
-        incNtfStat tknCreated
+        incNtfStatT token tknCreated
         pure (corrId, "", NRTknId tknId srvDhPubKey)
-      NtfReqCmd SToken (NtfTkn tkn@NtfTknData {ntfTknId, tknStatus, tknRegCode, tknDhSecret, tknDhKeys = (srvDhPubKey, srvDhPrivKey), tknCronInterval}) (corrId, tknId, cmd) -> do
+      NtfReqCmd SToken (NtfTkn tkn@NtfTknData {token, ntfTknId, tknStatus, tknRegCode, tknDhSecret, tknDhKeys = (srvDhPubKey, srvDhPrivKey), tknCronInterval}) (corrId, tknId, cmd) -> do
         status <- readTVarIO tknStatus
         (corrId,tknId,) <$> case cmd of
           TNEW (NewNtfTkn _ _ dhPubKey) -> do
@@ -474,7 +474,7 @@ client NtfServerClient {rcvQ, sndQ} NtfSubscriber {newSubQ, smpAgent = ca} NtfPu
                 updateTknStatus tkn NTActive
                 tIds <- atomically $ removeInactiveTokenRegistrations st tkn
                 forM_ tIds cancelInvervalNotifications
-                incNtfStat tknVerified
+                incNtfStatT token tknVerified
                 pure NROk
             | otherwise -> do
                 logDebug "TVFY - incorrect code or token status"
@@ -493,8 +493,8 @@ client NtfServerClient {rcvQ, sndQ} NtfSubscriber {newSubQ, smpAgent = ca} NtfPu
               addNtfToken st tknId tkn'
               writeTBQueue pushQ (tkn', PNVerification regCode)
             withNtfLog $ \s -> logUpdateToken s tknId token' regCode
-            incNtfStat tknDeleted
-            incNtfStat tknCreated
+            incNtfStatT token tknDeleted
+            incNtfStatT token tknCreated
             pure NROk
           TDEL -> do
             logDebug "TDEL"
@@ -504,7 +504,7 @@ client NtfServerClient {rcvQ, sndQ} NtfSubscriber {newSubQ, smpAgent = ca} NtfPu
               atomically $ removeSubscription ca smpServer (SPNotifier, notifierId)
             cancelInvervalNotifications tknId
             withNtfLog (`logDeleteToken` tknId)
-            incNtfStat tknDeleted
+            incNtfStatT token tknDeleted
             pure NROk
           TCRN 0 -> do
             logDebug "TCRN 0"
@@ -583,6 +583,10 @@ client NtfServerClient {rcvQ, sndQ} NtfSubscriber {newSubQ, smpAgent = ca} NtfPu
 withNtfLog :: (StoreLog 'WriteMode -> IO a) -> M ()
 withNtfLog action = liftIO . mapM_ action =<< asks storeLog
 
+incNtfStatT :: DeviceToken -> (NtfServerStats -> TVar Int) -> M ()
+incNtfStatT (DeviceToken PPApnsNull _) _ = pure ()
+incNtfStatT _ statSel = incNtfStat statSel
+
 incNtfStat :: (NtfServerStats -> TVar Int) -> M ()
 incNtfStat statSel = do
   stats <- asks serverStats

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

@@ -24,16 +24,16 @@ import Numeric.Natural
 import Simplex.Messaging.Client.Agent
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Notifications.Protocol
-import Simplex.Messaging.Notifications.Transport (NTFVersion, VersionRangeNTF)
 import Simplex.Messaging.Notifications.Server.Push.APNS
 import Simplex.Messaging.Notifications.Server.Stats
 import Simplex.Messaging.Notifications.Server.Store
 import Simplex.Messaging.Notifications.Server.StoreLog
+import Simplex.Messaging.Notifications.Transport (NTFVersion, VersionRangeNTF)
 import Simplex.Messaging.Protocol (CorrId, SMPServer, Transmission)
 import Simplex.Messaging.Server.Expiration
 import Simplex.Messaging.TMap (TMap)
 import qualified Simplex.Messaging.TMap as TM
-import Simplex.Messaging.Transport (ATransport, THandleParams)
+import Simplex.Messaging.Transport (ATransport, THandleParams, TransportPeer (..))
 import Simplex.Messaging.Transport.Server (TransportServerConfig, loadFingerprint, loadTLSServerParams)
 import System.IO (IOMode (..))
 import System.Mem.Weak (Weak)
@@ -161,13 +161,13 @@ data NtfRequest
 data NtfServerClient = NtfServerClient
   { rcvQ :: TBQueue NtfRequest,
     sndQ :: TBQueue (Transmission NtfResponse),
-    ntfThParams :: THandleParams NTFVersion,
+    ntfThParams :: THandleParams NTFVersion 'TServer,
     connected :: TVar Bool,
     rcvActiveAt :: TVar SystemTime,
     sndActiveAt :: TVar SystemTime
   }
 
-newNtfServerClient :: Natural -> THandleParams NTFVersion -> SystemTime -> STM NtfServerClient
+newNtfServerClient :: Natural -> THandleParams NTFVersion 'TServer -> SystemTime -> STM NtfServerClient
 newNtfServerClient qSize ntfThParams ts = do
   rcvQ <- newTBQueue qSize
   sndQ <- newTBQueue qSize

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

@@ -13,8 +13,7 @@ import Data.Maybe (fromMaybe)
 import qualified Data.Text as T
 import Network.Socket (HostName)
 import Options.Applicative
-import Simplex.Messaging.Client (ProtocolClientConfig (..))
-import Simplex.Messaging.Client.Agent (SMPClientAgentConfig (..), defaultSMPClientAgentConfig)
+import Simplex.Messaging.Client.Agent (defaultSMPClientAgentConfig)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Notifications.Server (runNtfServer)
 import Simplex.Messaging.Notifications.Server.Env (NtfServerConfig (..), defaultInactiveClientExpiration)
@@ -31,9 +30,6 @@ import System.FilePath (combine)
 import System.IO (BufferMode (..), hSetBuffering, stderr, stdout)
 import Text.Read (readMaybe)
 
-defaultSMPBatchDelay :: Int
-defaultSMPBatchDelay = 10000
-
 ntfServerCLI :: FilePath -> FilePath -> IO ()
 ntfServerCLI cfgPath logPath =
   getCliCommand' (cliCommandP cfgPath logPath iniFile) serverVersion >>= \case
@@ -87,9 +83,7 @@ ntfServerCLI cfgPath logPath =
                \# host is only used to print server address on start\n"
             <> ("host: " <> host <> "\n")
             <> ("port: " <> defaultServerPort <> "\n")
-            <> "log_tls_errors: off\n\
-               \# delay between command batches sent to SMP relays (microseconds), 0 to disable\n"
-            <> ("smp_batch_delay: " <> show defaultSMPBatchDelay <> "\n")
+            <> "log_tls_errors: off\n"
             <> "websockets: off\n\n\
                \[INACTIVE_CLIENTS]\n\
                \# TTL and interval to check inactive clients\n\
@@ -111,8 +105,6 @@ ntfServerCLI cfgPath logPath =
         enableStoreLog = settingIsOn "STORE_LOG" "enable" ini
         logStats = settingIsOn "STORE_LOG" "log_stats" ini
         c = combine cfgPath . ($ defaultX509Config)
-        smpBatchDelay = readIniDefault defaultSMPBatchDelay "TRANSPORT" "smp_batch_delay" ini
-        batchDelay = if smpBatchDelay <= 0 then Nothing else Just smpBatchDelay
         serverConfig =
           NtfServerConfig
             { transports = iniTransports ini,
@@ -121,7 +113,7 @@ ntfServerCLI cfgPath logPath =
               clientQSize = 64,
               subQSize = 512,
               pushQSize = 1048,
-              smpAgentCfg = defaultSMPClientAgentConfig {smpCfg = (smpCfg defaultSMPClientAgentConfig) {batchDelay}},
+              smpAgentCfg = defaultSMPClientAgentConfig,
               apnsConfig = defaultAPNSPushClientConfig,
               subsBatchSize = 900,
               inactiveClientExpiration =

src/Simplex/Messaging/Notifications/Server/Push/APNS.hs

@@ -27,9 +27,8 @@ import Data.Aeson (ToJSON, (.=))
 import qualified Data.Aeson as J
 import qualified Data.Aeson.Encoding as JE
 import qualified Data.Aeson.TH as JQ
-import Data.Base64.Types (extractBase64)
 import Data.Bifunctor (first)
-import qualified Data.ByteString.Base64.URL as UP
+import qualified Data.ByteString.Base64.URL as U
 import Data.ByteString.Builder (lazyByteString)
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Lazy.Char8 as LB
@@ -47,7 +46,6 @@ import Network.HTTP2.Client (Request)
 import qualified Network.HTTP2.Client as H
 import Network.Socket (HostName, ServiceName)
 import qualified Simplex.Messaging.Crypto as C
-import qualified Simplex.Messaging.Encoding.Base64.URL as U
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Notifications.Protocol
 import Simplex.Messaging.Notifications.Server.Push.APNS.Internal
@@ -56,7 +54,7 @@ import Simplex.Messaging.Parsers (defaultJSON)
 import Simplex.Messaging.Protocol (EncNMsgMeta)
 import Simplex.Messaging.Transport.HTTP2 (HTTP2Body (..))
 import Simplex.Messaging.Transport.HTTP2.Client
-import Simplex.Messaging.Util (safeDecodeUtf8)
+import Simplex.Messaging.Util (safeDecodeUtf8, tshow)
 import System.Environment (getEnv)
 import UnliftIO.STM
 
@@ -93,8 +91,8 @@ signedJWTToken pk (JWTToken hdr claims) = do
   pure $ hc <> "." <> serialize sig
   where
     jwtEncode :: ToJSON a => a -> ByteString
-    jwtEncode = extractBase64 . UP.encodeBase64Unpadded' . LB.toStrict . J.encode
-    serialize sig = extractBase64 . UP.encodeBase64Unpadded' $ encodeASN1' DER [Start Sequence, IntVal (EC.sign_r sig), IntVal (EC.sign_s sig), End Sequence]
+    jwtEncode = U.encodeUnpadded . LB.toStrict . J.encode
+    serialize sig = U.encodeUnpadded $ encodeASN1' DER [Start Sequence, IntVal (EC.sign_r sig), IntVal (EC.sign_s sig), End Sequence]
 
 readECPrivateKey :: FilePath -> IO EC.PrivateKey
 readECPrivateKey f = do
@@ -260,11 +258,11 @@ mkApnsJWTToken appTeamId jwtHeader privateKey = do
 connectHTTPS2 :: HostName -> APNSPushClientConfig -> TVar (Maybe HTTP2Client) -> IO (Either HTTP2ClientError HTTP2Client)
 connectHTTPS2 apnsHost APNSPushClientConfig {apnsPort, http2cfg, caStoreFile} https2Client = do
   caStore_ <- XS.readCertificateStore caStoreFile
-  when (isNothing caStore_) $ putStrLn $ "Error loading CertificateStore from " <> caStoreFile
+  when (isNothing caStore_) $ logError $ "Error loading CertificateStore from " <> T.pack caStoreFile
   r <- getHTTP2Client apnsHost apnsPort caStore_ http2cfg disconnected
   case r of
     Right client -> atomically . writeTVar https2Client $ Just client
-    Left e -> putStrLn $ "Error connecting to APNS: " <> show e
+    Left e -> logError $ "Error connecting to APNS: " <> tshow e
   pure r
   where
     disconnected = atomically $ writeTVar https2Client Nothing

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

@@ -24,9 +24,12 @@ module Simplex.Messaging.Notifications.Server.StoreLog
 where
 
 import Control.Concurrent.STM
+import Control.Logger.Simple
 import Control.Monad
 import qualified Data.Attoparsec.ByteString.Char8 as A
 import qualified Data.ByteString.Char8 as B
+import qualified Data.ByteString.Lazy.Char8 as LB
+import qualified Data.Text as T
 import Data.Word (Word16)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding.String
@@ -34,7 +37,7 @@ import Simplex.Messaging.Notifications.Protocol
 import Simplex.Messaging.Notifications.Server.Store
 import Simplex.Messaging.Protocol (NtfPrivateAuthKey)
 import Simplex.Messaging.Server.StoreLog
-import Simplex.Messaging.Util (whenM)
+import Simplex.Messaging.Util (safeDecodeUtf8, whenM)
 import System.Directory (doesFileExist, renameFile)
 import System.IO
 
@@ -189,10 +192,10 @@ readWriteNtfStore f st = do
   pure s
 
 readNtfStore :: FilePath -> NtfStore -> IO ()
-readNtfStore f st = mapM_ addNtfLogRecord . B.lines =<< B.readFile f
+readNtfStore f st = mapM_ (addNtfLogRecord . LB.toStrict) . LB.lines =<< LB.readFile f
   where
     addNtfLogRecord s = case strDecode s of
-      Left e -> B.putStrLn $ "Log parsing error (" <> B.pack e <> "): " <> B.take 100 s
+      Left e -> logError $ "Log parsing error (" <> T.pack e <> "): " <> safeDecodeUtf8 (B.take 100 s)
       Right lr -> atomically $ case lr of
         CreateToken r@NtfTknRec {ntfTknId} -> do
           tkn <- mkTknData r

src/Simplex/Messaging/Notifications/Transport.hs

@@ -5,6 +5,7 @@
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE PatternSynonyms #-}
 {-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE TupleSections #-}
 
 module Simplex.Messaging.Notifications.Transport where
 
@@ -18,9 +19,9 @@ import qualified Data.X509 as X
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Transport
+import Simplex.Messaging.Util (liftEitherWith)
 import Simplex.Messaging.Version
 import Simplex.Messaging.Version.Internal
-import Simplex.Messaging.Util (liftEitherWith)
 
 ntfBlockSize :: Int
 ntfBlockSize = 512
@@ -54,7 +55,7 @@ supportedClientNTFVRange = mkVersionRange initialNTFVersion currentClientNTFVers
 supportedServerNTFVRange :: VersionRangeNTF
 supportedServerNTFVRange = mkVersionRange initialNTFVersion currentServerNTFVersion
 
-type THandleNTF c = THandle NTFVersion c
+type THandleNTF c p = THandle NTFVersion c p
 
 data NtfServerHandshake = NtfServerHandshake
   { ntfVersionRange :: VersionRangeNTF,
@@ -67,9 +68,7 @@ data NtfClientHandshake = NtfClientHandshake
   { -- | agreed SMP notifications server protocol version
     ntfVersion :: VersionNTF,
     -- | server identity - CA certificate fingerprint
-    keyHash :: C.KeyHash,
-    -- pub key to agree shared secret for entity ID encryption, shared secret for command authorization is agreed using per-queue keys.
-    authPubKey :: Maybe C.PublicKeyX25519
+    keyHash :: C.KeyHash
   }
 
 instance Encoding NtfServerHandshake where
@@ -94,62 +93,61 @@ authEncryptCmdsP :: VersionNTF -> Parser a -> Parser (Maybe a)
 authEncryptCmdsP v p = if v >= authBatchCmdsNTFVersion then Just <$> p else pure Nothing
 
 instance Encoding NtfClientHandshake where
-  smpEncode NtfClientHandshake {ntfVersion, keyHash, authPubKey} =
-    smpEncode (ntfVersion, keyHash) <> encodeNtfAuthPubKey ntfVersion authPubKey
+  smpEncode NtfClientHandshake {ntfVersion, keyHash} =
+    smpEncode (ntfVersion, keyHash)
   smpP = do
     (ntfVersion, keyHash) <- smpP
-    -- TODO drop SMP v6: remove special parser and make key non-optional
-    authPubKey <- ntfAuthPubKeyP ntfVersion
-    pure NtfClientHandshake {ntfVersion, keyHash, authPubKey}
-
-ntfAuthPubKeyP :: VersionNTF -> Parser (Maybe C.PublicKeyX25519)
-ntfAuthPubKeyP v = if v >= authBatchCmdsNTFVersion then Just <$> smpP else pure Nothing
-
-encodeNtfAuthPubKey :: VersionNTF -> Maybe C.PublicKeyX25519 -> ByteString
-encodeNtfAuthPubKey v k
-  | v >= authBatchCmdsNTFVersion = maybe "" smpEncode k
-  | otherwise = ""
+    pure NtfClientHandshake {ntfVersion, keyHash}
 
 -- | Notifcations server transport handshake.
-ntfServerHandshake :: forall c. Transport c => C.APrivateSignKey -> c -> C.KeyPairX25519 -> C.KeyHash -> VersionRangeNTF -> ExceptT TransportError IO (THandleNTF c)
+ntfServerHandshake :: forall c. Transport c => C.APrivateSignKey -> c -> C.KeyPairX25519 -> C.KeyHash -> VersionRangeNTF -> ExceptT TransportError IO (THandleNTF c 'TServer)
 ntfServerHandshake serverSignKey c (k, pk) kh ntfVRange = do
   let th@THandle {params = THandleParams {sessionId}} = ntfTHandle c
   let sk = C.signX509 serverSignKey $ C.publicToX509 k
   sendHandshake th $ NtfServerHandshake {sessionId, ntfVersionRange = ntfVRange, authPubKey = Just sk}
   getHandshake th >>= \case
-    NtfClientHandshake {ntfVersion = v, keyHash, authPubKey = k'}
+    NtfClientHandshake {ntfVersion = v, keyHash}
       | keyHash /= kh ->
           throwError $ TEHandshake IDENTITY
       | v `isCompatible` ntfVRange ->
-          pure $ ntfThHandle th v pk k'
+          pure $ ntfThHandleServer th v pk
       | otherwise -> throwError $ TEHandshake VERSION
 
 -- | Notifcations server client transport handshake.
-ntfClientHandshake :: forall c. Transport c => c -> C.KeyPairX25519 -> C.KeyHash -> VersionRangeNTF -> ExceptT TransportError IO (THandleNTF c)
-ntfClientHandshake c (k, pk) keyHash ntfVRange = do
+ntfClientHandshake :: forall c. Transport c => c -> C.KeyHash -> VersionRangeNTF -> ExceptT TransportError IO (THandleNTF c 'TClient)
+ntfClientHandshake c keyHash ntfVRange = do
   let th@THandle {params = THandleParams {sessionId}} = ntfTHandle c
   NtfServerHandshake {sessionId = sessId, ntfVersionRange, authPubKey = sk'} <- getHandshake th
   if sessionId /= sessId
     then throwError TEBadSession
     else case ntfVersionRange `compatibleVersion` ntfVRange of
       Just (Compatible v) -> do
-        sk_ <- forM sk' $ \exact -> liftEitherWith (const $ TEHandshake BAD_AUTH) $ do
+        ck_ <- forM sk' $ \signedKey -> liftEitherWith (const $ TEHandshake BAD_AUTH) $ do
           serverKey <- getServerVerifyKey c
-          pubKey <- C.verifyX509 serverKey exact
-          C.x509ToPublic (pubKey, []) >>= C.pubKey
-        sendHandshake th $ NtfClientHandshake {ntfVersion = v, keyHash, authPubKey = Just k}
-        pure $ ntfThHandle th v pk sk_
+          pubKey <- C.verifyX509 serverKey signedKey
+          (,(getServerCerts c, signedKey)) <$> (C.x509ToPublic (pubKey, []) >>= C.pubKey)
+        sendHandshake th $ NtfClientHandshake {ntfVersion = v, keyHash}
+        pure $ ntfThHandleClient th v ck_
       Nothing -> throwError $ TEHandshake VERSION
 
-ntfThHandle :: forall c. THandleNTF c -> VersionNTF -> C.PrivateKeyX25519 -> Maybe C.PublicKeyX25519 -> THandleNTF c
-ntfThHandle th@THandle {params} v privKey k_ =
-  -- TODO drop SMP v6: make thAuth non-optional
-  let thAuth = (\k -> THandleAuth {peerPubKey = k, privKey}) <$> k_
-      v3 = v >= authBatchCmdsNTFVersion
-      params' = params {thVersion = v, thAuth, implySessId = v3, batch = v3}
-   in (th :: THandleNTF c) {params = params'}
+ntfThHandleServer :: forall c. THandleNTF c 'TServer -> VersionNTF -> C.PrivateKeyX25519 -> THandleNTF c 'TServer
+ntfThHandleServer th v pk =
+  let thAuth = THAuthServer {serverPrivKey = pk, sessSecret' = Nothing}
+   in ntfThHandle_ th v (Just thAuth)
 
-ntfTHandle :: Transport c => c -> THandleNTF c
+ntfThHandleClient :: forall c. THandleNTF c 'TClient -> VersionNTF -> Maybe (C.PublicKeyX25519, (X.CertificateChain, X.SignedExact X.PubKey)) -> THandleNTF c 'TClient
+ntfThHandleClient th v ck_ =
+  let thAuth = (\(k, ck) -> THAuthClient {serverPeerPubKey = k, serverCertKey = ck, sessSecret = Nothing}) <$> ck_
+   in ntfThHandle_ th v thAuth
+
+ntfThHandle_ :: forall c p. THandleNTF c p -> VersionNTF -> Maybe (THandleAuth p) -> THandleNTF c p
+ntfThHandle_ th@THandle {params} v thAuth =
+  -- TODO drop SMP v6: make thAuth non-optional
+  let v3 = v >= authBatchCmdsNTFVersion
+      params' = params {thVersion = v, thAuth, implySessId = v3, batch = v3}
+   in (th :: THandleNTF c p) {params = params'}
+
+ntfTHandle :: Transport c => c -> THandleNTF c p
 ntfTHandle c = THandle {connection = c, params}
   where
     params = THandleParams {sessionId = tlsUnique c, blockSize = ntfBlockSize, thVersion = VersionNTF 0, thAuth = Nothing, implySessId = False, batch = False}

src/Simplex/Messaging/Parsers.hs

@@ -10,9 +10,10 @@ import qualified Data.Aeson as J
 import Data.Attoparsec.ByteString.Char8 (Parser)
 import qualified Data.Attoparsec.ByteString.Char8 as A
 import Data.Bifunctor (first)
+import Data.ByteString.Base64
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
-import Data.Char (toLower)
+import Data.Char (isAlphaNum, toLower)
 import Data.String
 import Data.Text (Text)
 import qualified Data.Text as T
@@ -23,8 +24,23 @@ import Database.SQLite.Simple (ResultError (..), SQLData (..))
 import Database.SQLite.Simple.FromField (FieldParser, returnError)
 import Database.SQLite.Simple.Internal (Field (..))
 import Database.SQLite.Simple.Ok (Ok (Ok))
+import Simplex.Messaging.Util ((<$?>))
 import Text.Read (readMaybe)
 
+base64P :: Parser ByteString
+base64P = decode <$?> paddedBase64 rawBase64P
+
+paddedBase64 :: Parser ByteString -> Parser ByteString
+paddedBase64 raw = (<>) <$> raw <*> pad
+  where
+    pad = A.takeWhile (== '=')
+
+rawBase64P :: Parser ByteString
+rawBase64P = A.takeWhile1 (\c -> isAlphaNum c || c == '+' || c == '/')
+
+-- rawBase64UriP :: Parser ByteString
+-- rawBase64UriP = A.takeWhile1 (\c -> isAlphaNum c || c == '-' || c == '_')
+
 tsISO8601P :: Parser UTCTime
 tsISO8601P = maybe (fail "timestamp") pure . parseISO8601 . B.unpack =<< A.takeTill wordEnd
 

src/Simplex/Messaging/Protocol.hs

@@ -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,
@@ -174,6 +184,7 @@ import qualified Data.Aeson.TH as J
 import Data.Attoparsec.ByteString.Char8 (Parser, (<?>))
 import qualified Data.Attoparsec.ByteString.Char8 as A
 import Data.Bifunctor (first)
+import qualified Data.ByteString.Base64 as B64
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
 import Data.Char (isPrint, isSpace)
@@ -184,20 +195,24 @@ 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
-import qualified Simplex.Messaging.Encoding.Base64 as B64
 import Simplex.Messaging.Encoding.String
 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)
@@ -244,7 +273,7 @@ e2eEncMessageLength :: Int
 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
@@ -1074,8 +1192,23 @@ 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 -> Parser RawTransmission
+transmissionP :: THandleParams v p -> Parser RawTransmission
 transmissionP THandleParams {sessionId, implySessId} = do
   authenticator <- smpP
   authorized <- A.takeByteString
@@ -1089,10 +1222,10 @@ transmissionP THandleParams {sessionId, implySessId} = do
       command <- A.takeByteString
       pure RawTransmission {authenticator, authorized = authorized', sessId, corrId, entityId, command}
 
-class (ProtocolEncoding v err msg, ProtocolEncoding v err (ProtoCommand msg), Show err, Show msg) => Protocol v err msg | msg -> v, msg -> err  where
+class (ProtocolEncoding v err msg, ProtocolEncoding v err (ProtoCommand msg), Show err, Show msg) => Protocol v err msg | msg -> v, msg -> err where
   type ProtoCommand msg = cmd | cmd -> msg
   type ProtoType msg = (sch :: ProtocolType) | sch -> msg
-  protocolClientHandshake :: forall c. Transport c => c -> C.KeyPairX25519 -> C.KeyHash -> VersionRange v -> ExceptT TransportError IO (THandle v c)
+  protocolClientHandshake :: forall c. Transport c => c -> Maybe C.KeyPairX25519 -> C.KeyHash -> VersionRange v -> ExceptT TransportError IO (THandle v c 'TClient)
   protocolPing :: ProtoCommand msg
   protocolError :: msg -> Maybe err
 
@@ -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
@@ -1304,11 +1469,49 @@ 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 -> NonEmpty (Either TransportError SentRawTransmission) -> IO [Either TransportError ()]
+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)
   where
     tPutBatch :: TransportBatch () -> IO [Either TransportError ()]
@@ -1317,7 +1520,7 @@ tPut th@THandle {params} = fmap concat . mapM tPutBatch . batchTransmissions (ba
       TBTransmissions s n _ -> replicate n <$> tPutLog th s
       TBTransmission s _ -> (: []) <$> tPutLog th s
 
-tPutLog :: Transport c => THandle v c -> ByteString -> IO (Either TransportError ())
+tPutLog :: Transport c => THandle v c p -> ByteString -> IO (Either TransportError ())
 tPutLog th s = do
   r <- tPutBlock th s
   case r of
@@ -1383,7 +1586,7 @@ tEncodeBatch1 t = lenEncode 1 `B.cons` tEncodeForBatch t
 -- tForAuth is lazy to avoid computing it when there is no key to sign
 data TransmissionForAuth = TransmissionForAuth {tForAuth :: ~ByteString, tToSend :: ByteString}
 
-encodeTransmissionForAuth :: ProtocolEncoding v e c => THandleParams v -> Transmission c -> TransmissionForAuth
+encodeTransmissionForAuth :: ProtocolEncoding v e c => THandleParams v p -> Transmission c -> TransmissionForAuth
 encodeTransmissionForAuth THandleParams {thVersion = v, sessionId, implySessId} t =
   TransmissionForAuth {tForAuth, tToSend = if implySessId then t' else tForAuth}
   where
@@ -1391,7 +1594,7 @@ encodeTransmissionForAuth THandleParams {thVersion = v, sessionId, implySessId}
     t' = encodeTransmission_ v t
 {-# INLINE encodeTransmissionForAuth #-}
 
-encodeTransmission :: ProtocolEncoding v e c => THandleParams v -> Transmission c -> ByteString
+encodeTransmission :: ProtocolEncoding v e c => THandleParams v p -> Transmission c -> ByteString
 encodeTransmission THandleParams {thVersion = v, sessionId, implySessId} t =
   if implySessId then t' else smpEncode sessionId <> t'
   where
@@ -1404,11 +1607,11 @@ encodeTransmission_ v (CorrId corrId, queueId, command) =
 {-# INLINE encodeTransmission_ #-}
 
 -- | Receive and parse transmission from the TCP transport (ignoring any trailing padding).
-tGetParse :: Transport c => THandle v c -> IO (NonEmpty (Either TransportError RawTransmission))
+tGetParse :: Transport c => THandle v c p -> IO (NonEmpty (Either TransportError RawTransmission))
 tGetParse th@THandle {params} = eitherList (tParse params) <$> tGetBlock th
 {-# INLINE tGetParse #-}
 
-tParse :: THandleParams v -> ByteString -> NonEmpty (Either TransportError RawTransmission)
+tParse :: THandleParams v p -> ByteString -> NonEmpty (Either TransportError RawTransmission)
 tParse thParams@THandleParams {batch} s
   | batch = eitherList (L.map (\(Large t) -> tParse1 t)) ts
   | otherwise = [tParse1 s]
@@ -1420,10 +1623,10 @@ eitherList :: (a -> NonEmpty (Either e b)) -> Either e a -> NonEmpty (Either e b
 eitherList = either (\e -> [Left e])
 
 -- | Receive client and server transmissions (determined by `cmd` type).
-tGet :: forall v err cmd c. (ProtocolEncoding v err cmd, Transport c) => THandle v c -> IO (NonEmpty (SignedTransmission err cmd))
+tGet :: forall v err cmd c p. (ProtocolEncoding v err cmd, Transport c) => THandle v c p -> IO (NonEmpty (SignedTransmission err cmd))
 tGet th@THandle {params} = L.map (tDecodeParseValidate params) <$> tGetParse th
 
-tDecodeParseValidate :: forall v err cmd. ProtocolEncoding v err cmd => THandleParams v -> Either TransportError RawTransmission -> SignedTransmission err cmd
+tDecodeParseValidate :: forall v p err cmd. ProtocolEncoding v err cmd => THandleParams v p -> Either TransportError RawTransmission -> SignedTransmission err cmd
 tDecodeParseValidate THandleParams {sessionId, thVersion = v, implySessId} = \case
   Right RawTransmission {authenticator, authorized, sessId, corrId, entityId, command}
     | implySessId || sessId == sessionId ->
@@ -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])

src/Simplex/Messaging/Server.hs

@@ -13,7 +13,6 @@
 {-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TupleSections #-}
-{-# LANGUAGE TypeApplications #-}
 
 -- |
 -- Module      : Simplex.Messaging.Server
@@ -43,15 +42,19 @@ 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)
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
+import qualified Data.ByteString.Lazy.Char8 as LB
 import Data.Either (fromRight, partitionEithers)
 import Data.Functor (($>))
 import Data.Int (Int64)
 import qualified Data.IntMap.Strict as IM
 import Data.List (intercalate)
+import Data.List.NonEmpty (NonEmpty)
 import qualified Data.List.NonEmpty as L
 import qualified Data.Map.Strict as M
 import Data.Maybe (isNothing)
@@ -65,9 +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.Base64 (encode)
+import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Protocol
 import Simplex.Messaging.Server.Control
@@ -89,6 +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
@@ -121,11 +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)
@@ -178,6 +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_ _ = []
@@ -313,7 +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
@@ -408,8 +428,8 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg} = do
                     logError "Unauthorized control port command"
                     hPutStrLn h "AUTH"
 
-runClientTransport :: Transport c => THandleSMP c -> M ()
-runClientTransport th@THandle {params = THandleParams {thVersion, sessionId}} = do
+runClientTransport :: Transport c => THandleSMP c 'TServer -> M ()
+runClientTransport th@THandle {params = thParams@THandleParams {thVersion, sessionId}} = do
   q <- asks $ tbqSize . config
   ts <- liftIO getSystemTime
   active <- asks clients
@@ -421,7 +441,7 @@ runClientTransport th@THandle {params = THandleParams {thVersion, sessionId}} =
   s <- asks server
   expCfg <- asks $ inactiveClientExpiration . config
   labelMyThread . B.unpack $ "client $" <> encode sessionId
-  raceAny_ ([liftIO $ send th c, client c s, receive th 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 th (rcvActiveAt c) (sndActiveAt c) expCfg (noSubscriptions c)]
@@ -456,28 +476,28 @@ cancelSub sub =
     Sub {subThread = SubThread t} -> liftIO $ deRefWeak t >>= mapM_ killThread
     _ -> return ()
 
-receive :: Transport c => THandleSMP c -> Client -> M ()
+receive :: Transport c => THandleSMP c 'TServer -> Client -> M ()
 receive th@THandle {params = THandleParams {thAuth}} Client {rcvQ, sndQ, rcvActiveAt, sessionId} = do
   labelMyThread . B.unpack $ "client $" <> encode sessionId <> " receive"
   forever $ do
     ts <- L.toList <$> liftIO (tGet th)
     atomically . writeTVar rcvActiveAt =<< liftIO getSystemTime
-    as <- partitionEithers <$> 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 => THandleSMP c -> Client -> IO ()
+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 $ do
@@ -492,7 +512,7 @@ send h@THandle {params} Client {sndQ, sessionId, sndActiveAt} = do
       NMSG {} -> 0
       _ -> 1
 
-disconnectTransport :: Transport c => THandle v c -> TVar SystemTime -> TVar SystemTime -> ExpirationConfig -> IO Bool -> IO ()
+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
   labelMyThread . B.unpack $ "client $" <> encode sessionId <> " disconnectTransport"
   loop
@@ -513,7 +533,7 @@ data VerificationResult = VRVerified (Maybe QueueRec) | VRFailed
 -- - the queue or party key do not exist.
 -- In all cases, the time of the verification should depend only on the provided authorization type,
 -- a dummy key is used to run verification in the last two cases, and failure is returned irrespective of the result.
-verifyTransmission :: Maybe (THandleAuth, C.CbNonce) -> Maybe TransmissionAuth -> ByteString -> QueueId -> Cmd -> M VerificationResult
+verifyTransmission :: Maybe (THandleAuth 'TServer, C.CbNonce) -> Maybe TransmissionAuth -> ByteString -> QueueId -> Cmd -> M VerificationResult
 verifyTransmission auth_ tAuth authorized queueId cmd =
   case cmd of
     Cmd SRecipient (NEW k _ _ _) -> pure $ Nothing `verifiedWith` k
@@ -521,21 +541,23 @@ 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
 
-verifyCmdAuthorization :: Maybe (THandleAuth, C.CbNonce) -> Maybe TransmissionAuth -> ByteString -> C.APublicAuthKey -> Bool
+verifyCmdAuthorization :: Maybe (THandleAuth 'TServer, C.CbNonce) -> Maybe TransmissionAuth -> ByteString -> C.APublicAuthKey -> Bool
 verifyCmdAuthorization auth_ tAuth authorized key = maybe False (verify key) tAuth
   where
     verify :: C.APublicAuthKey -> TransmissionAuth -> Bool
@@ -547,12 +569,12 @@ verifyCmdAuthorization auth_ tAuth authorized key = maybe False (verify key) tAu
         C.SX25519 -> verifyCmdAuth auth_ k s authorized
         _ -> verifyCmdAuth auth_ dummyKeyX25519 s authorized `seq` False
 
-verifyCmdAuth :: Maybe (THandleAuth, C.CbNonce) -> C.PublicKeyX25519 -> C.CbAuthenticator -> ByteString -> Bool
+verifyCmdAuth :: Maybe (THandleAuth 'TServer, C.CbNonce) -> C.PublicKeyX25519 -> C.CbAuthenticator -> ByteString -> Bool
 verifyCmdAuth auth_ k authenticator authorized = case auth_ of
-  Just (THandleAuth {privKey}, nonce) -> C.cbVerify k privKey nonce authenticator authorized
+  Just (THAuthServer {serverPrivKey = pk}, nonce) -> C.cbVerify k pk nonce authenticator authorized
   Nothing -> False
 
-dummyVerifyCmd :: Maybe (THandleAuth, C.CbNonce) -> ByteString -> TransmissionAuth -> Bool
+dummyVerifyCmd :: Maybe (THandleAuth 'TServer, C.CbNonce) -> ByteString -> TransmissionAuth -> Bool
 dummyVerifyCmd auth_ authorized = \case
   TASignature (C.ASignature a s) -> C.verify' (dummySignKey a) s authorized
   TAAuthenticator s -> verifyCmdAuth auth_ dummyKeyX25519 s authorized
@@ -580,25 +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
@@ -862,6 +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
@@ -983,7 +1086,7 @@ restoreServerMessages = asks (storeMsgsFile . config) >>= \case
       ms <- asks msgStore
       quota <- asks $ msgQueueQuota . config
       old_ <- asks (messageExpiration . config) $>>= (liftIO . fmap Just . expireBeforeEpoch)
-      runExceptT (liftIO (B.readFile f) >>= foldM (\expired -> restoreMsg expired ms quota old_) 0 . B.lines) >>= \case
+      runExceptT (liftIO (LB.readFile f) >>= foldM (\expired -> restoreMsg expired ms quota old_) 0 . LB.lines) >>= \case
         Left e -> do
           logError . T.pack $ "error restoring messages: " <> e
           liftIO exitFailure
@@ -992,10 +1095,11 @@ restoreServerMessages = asks (storeMsgsFile . config) >>= \case
           logInfo "messages restored"
           pure expired
       where
-        restoreMsg !expired ms quota old_ s = do
+        restoreMsg !expired ms quota old_ s' = do
           MLRv3 rId msg <- liftEither . first (msgErr "parsing") $ strDecode s
           addToMsgQueue rId msg
           where
+            s = LB.toStrict s'
             addToMsgQueue rId msg = do
               (isExpired, logFull) <- atomically $ do
                 q <- getMsgQueue ms rId quota

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

@@ -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
@@ -33,7 +34,7 @@ import Simplex.Messaging.Server.Stats
 import Simplex.Messaging.Server.StoreLog
 import Simplex.Messaging.TMap (TMap)
 import qualified Simplex.Messaging.TMap as TM
-import Simplex.Messaging.Transport (ATransport, VersionSMP, VersionRangeSMP)
+import Simplex.Messaging.Transport (ATransport, VersionRangeSMP, VersionSMP)
 import Simplex.Messaging.Transport.Server (SocketState, TransportServerConfig, loadFingerprint, loadTLSServerParams, newSocketState)
 import System.IO (IOMode (..))
 import System.Mem.Weak (Weak)
@@ -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
@@ -122,8 +126,14 @@ 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)),
@@ -135,7 +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
@@ -154,7 +165,7 @@ 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
@@ -166,7 +177,8 @@ newClient nextClientId qSize thVersion sessionId createdAt = do
   connected <- newTVar True
   rcvActiveAt <- newTVar createdAt
   sndActiveAt <- newTVar createdAt
-  return Client {clientId, subscriptions, ntfSubscriptions, rcvQ, sndQ, 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
@@ -174,7 +186,7 @@ newSubscription subThread = do
   return Sub {subThread, delivered}
 
 newEnv :: ServerConfig -> IO Env
-newEnv config@ServerConfig {caCertificateFile, certificateFile, privateKeyFile, storeLogFile} = do
+newEnv config@ServerConfig {caCertificateFile, certificateFile, privateKeyFile, storeLogFile, smpAgentCfg} = do
   server <- atomically newServer
   queueStore <- atomically newQueueStore
   msgStore <- atomically newMsgStore
@@ -187,7 +199,8 @@ newEnv config@ServerConfig {caCertificateFile, certificateFile, privateKeyFile,
   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
@@ -203,3 +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}

src/Simplex/Messaging/Server/Main.hs

@@ -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, 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)
@@ -213,7 +216,9 @@ smpServerCLI cfgPath logPath =
                 defaultTransportServerConfig
                   { 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
@@ -305,4 +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
-

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

@@ -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

src/Simplex/Messaging/Server/StoreLog.hs

@@ -25,8 +25,8 @@ where
 
 import Control.Applicative (optional, (<|>))
 import Control.Monad (foldM, unless, when)
-import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
+import qualified Data.ByteString.Lazy.Char8 as LB
 import Data.Functor (($>))
 import Data.Map.Strict (Map)
 import qualified Data.Map.Strict as M
@@ -148,13 +148,14 @@ writeQueues s = mapM_ $ \q -> when (active q) $ logCreateQueue s q
     active QueueRec {status} = status == QueueActive
 
 readQueues :: FilePath -> IO (Map RecipientId QueueRec)
-readQueues f = foldM processLine M.empty . B.lines =<< B.readFile f
+readQueues f = foldM processLine M.empty . LB.lines =<< LB.readFile f
   where
-    processLine :: Map RecipientId QueueRec -> ByteString -> IO (Map RecipientId QueueRec)
-    processLine m s = case strDecode $ trimCR s of
+    processLine :: Map RecipientId QueueRec -> LB.ByteString -> IO (Map RecipientId QueueRec)
+    processLine m s' = case strDecode $ trimCR s of
       Right r -> pure $ procLogRecord r
       Left e -> printError e $> m
       where
+        s = LB.toStrict s'
         procLogRecord :: StoreLogRecord -> Map RecipientId QueueRec
         procLogRecord = \case
           CreateQueue q -> M.insert (recipientId q) q m

src/Simplex/Messaging/Session.hs

@@ -0,0 +1,38 @@
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+
+module Simplex.Messaging.Session where
+
+import Control.Concurrent.STM
+import Control.Monad
+import Data.Composition ((.:.))
+import Data.Functor (($>))
+import Simplex.Messaging.TMap (TMap)
+import qualified Simplex.Messaging.TMap as TM
+
+data SessionVar a = SessionVar
+  { sessionVar :: TMVar a,
+    sessionVarId :: Int
+  }
+
+getSessVar :: forall k a. Ord k => TVar Int -> k -> TMap k (SessionVar a) -> STM (Either (SessionVar a) (SessionVar a))
+getSessVar sessSeq sessKey vs = maybe (Left <$> newSessionVar) (pure . Right) =<< TM.lookup sessKey vs
+  where
+    newSessionVar :: STM (SessionVar a)
+    newSessionVar = do
+      sessionVar <- newEmptyTMVar
+      sessionVarId <- stateTVar sessSeq $ \next -> (next, next + 1)
+      let v = SessionVar {sessionVar, sessionVarId}
+      TM.insert sessKey v vs
+      pure v
+
+removeSessVar :: Ord k => SessionVar a -> k -> TMap k (SessionVar a) -> STM ()
+removeSessVar = void .:. removeSessVar'
+{-# INLINE removeSessVar #-}
+
+removeSessVar' :: Ord k => SessionVar a -> k -> TMap k (SessionVar a) -> STM Bool
+removeSessVar' v sessKey vs =
+  TM.lookup sessKey vs >>= \case
+    Just v' | sessionVarId v == sessionVarId v' -> TM.delete sessKey vs $> True
+    _ -> pure False

src/Simplex/Messaging/Transport.hs

@@ -12,6 +12,7 @@
 {-# LANGUAGE PatternSynonyms #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE TupleSections #-}
 {-# LANGUAGE TypeApplications #-}
 
 -- |
@@ -40,6 +41,7 @@ module Simplex.Messaging.Transport
     basicAuthSMPVersion,
     subModeSMPVersion,
     authCmdsSMPVersion,
+    sendingProxySMPVersion,
     simplexMQVersion,
     smpBlockSize,
     TransportConfig (..),
@@ -54,6 +56,7 @@ module Simplex.Messaging.Transport
     -- * TLS Transport
     TLS (..),
     SessionId,
+    ALPN,
     connectTLS,
     closeTLS,
     supportedParameters,
@@ -76,7 +79,7 @@ module Simplex.Messaging.Transport
   )
 where
 
-import Control.Applicative ((<|>))
+import Control.Applicative (optional, (<|>))
 import Control.Monad (forM)
 import Control.Monad.Except
 import Control.Monad.Trans.Except (throwE)
@@ -112,6 +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
 
@@ -147,6 +155,9 @@ subModeSMPVersion = VersionSMP 6
 authCmdsSMPVersion :: VersionSMP
 authCmdsSMPVersion = VersionSMP 7
 
+sendingProxySMPVersion :: VersionSMP
+sendingProxySMPVersion = VersionSMP 8
+
 currentClientSMPRelayVersion :: VersionSMP
 currentClientSMPRelayVersion = VersionSMP 6
 
@@ -228,10 +239,13 @@ data TLS = TLS
     tlsPeer :: TransportPeer,
     tlsUniq :: ByteString,
     tlsBuffer :: TBuffer,
+    tlsALPN :: Maybe ALPN,
     tlsServerCerts :: X.CertificateChain,
     tlsTransportConfig :: TransportConfig
   }
 
+type ALPN = ByteString
+
 connectTLS :: T.TLSParams p => Maybe HostName -> TransportConfig -> p -> Socket -> IO T.Context
 connectTLS host_ TransportConfig {logTLSErrors} params sock =
   E.bracketOnError (T.contextNew sock params) closeTLS $ \ctx ->
@@ -246,7 +260,8 @@ getTLS tlsPeer cfg tlsServerCerts cxt = withTlsUnique tlsPeer cxt newTLS
   where
     newTLS tlsUniq = do
       tlsBuffer <- atomically newTBuffer
-      pure TLS {tlsContext = cxt, tlsTransportConfig = cfg, tlsServerCerts, tlsPeer, tlsUniq, tlsBuffer}
+      tlsALPN <- T.getNegotiatedProtocol cxt
+      pure TLS {tlsContext = cxt, tlsALPN, tlsTransportConfig = cfg, tlsServerCerts, tlsPeer, tlsUniq, tlsBuffer}
 
 withTlsUnique :: TransportPeer -> T.Context -> (ByteString -> IO c) -> IO c
 withTlsUnique peer cxt f =
@@ -306,20 +321,20 @@ instance Transport TLS where
 -- * SMP transport
 
 -- | The handle for SMP encrypted transport connection over Transport.
-data THandle v c = THandle
+data THandle v c p = THandle
   { connection :: c,
-    params :: THandleParams v
+    params :: THandleParams v p
   }
 
-type THandleSMP c = THandle SMPVersion c
+type THandleSMP c p = THandle SMPVersion c p
 
-data THandleParams v = THandleParams
+data THandleParams v p = THandleParams
   { sessionId :: SessionId,
     blockSize :: Int,
     -- | agreed server protocol version
     thVersion :: Version v,
     -- | peer public key for command authorization and shared secrets for entity ID encryption
-    thAuth :: Maybe THandleAuth,
+    thAuth :: Maybe (THandleAuth p),
     -- | do NOT send session ID in transmission, but include it into signed message
     -- based on protocol version
     implySessId :: Bool,
@@ -328,10 +343,18 @@ data THandleParams v = THandleParams
     batch :: Bool
   }
 
-data THandleAuth = THandleAuth
-  { peerPubKey :: C.PublicKeyX25519, -- used only in the client to combine with per-queue key
-    privKey :: C.PrivateKeyX25519 -- used to combine with peer's per-queue key (currently only in the server)
-  }
+data THandleAuth (p :: TransportPeer) where
+  THAuthClient ::
+    { serverPeerPubKey :: C.PublicKeyX25519, -- used by the client to combine with client's private per-queue key
+      serverCertKey :: (X.CertificateChain, X.SignedExact X.PubKey), -- the key here is serverPeerPubKey signed with server certificate
+      sessSecret :: Maybe C.DhSecretX25519 -- session secret (will be used in SMP proxy only)
+    } ->
+    THandleAuth 'TClient
+  THAuthServer ::
+    { serverPrivKey :: C.PrivateKeyX25519, -- used by the server to combine with client's public per-queue key
+      sessSecret' :: Maybe C.DhSecretX25519 -- session secret (will be used in SMP proxy only)
+    } ->
+    THandleAuth 'TServer
 
 -- | TLS-unique channel binding
 type SessionId = ByteString
@@ -340,6 +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)
   }
 
@@ -385,7 +409,7 @@ encodeAuthEncryptCmds v k
   | otherwise = ""
 
 authEncryptCmdsP :: VersionSMP -> Parser a -> Parser (Maybe a)
-authEncryptCmdsP v p = if v >= authCmdsSMPVersion then Just <$> p else pure Nothing
+authEncryptCmdsP v p = if v >= authCmdsSMPVersion then optional p else pure Nothing
 
 -- | Error of SMP encrypted transport over TCP.
 data TransportError
@@ -433,13 +457,13 @@ serializeTransportError = \case
   TEHandshake e -> "HANDSHAKE " <> bshow e
 
 -- | Pad and send block to SMP transport.
-tPutBlock :: Transport c => THandle v c -> ByteString -> IO (Either TransportError ())
+tPutBlock :: Transport c => THandle v c p -> ByteString -> IO (Either TransportError ())
 tPutBlock THandle {connection = c, params = THandleParams {blockSize}} block =
   bimapM (const $ pure TELargeMsg) (cPut c) $
     C.pad block blockSize
 
 -- | Receive block from SMP transport.
-tGetBlock :: Transport c => THandle v c -> IO (Either TransportError ByteString)
+tGetBlock :: Transport c => THandle v c p -> IO (Either TransportError ByteString)
 tGetBlock THandle {connection = c, params = THandleParams {blockSize}} = do
   msg <- cGet c blockSize
   if B.length msg == blockSize
@@ -449,7 +473,7 @@ tGetBlock THandle {connection = c, params = THandleParams {blockSize}} = do
 -- | Server SMP transport handshake.
 --
 -- See https://github.com/simplex-chat/simplexmq/blob/master/protocol/simplex-messaging.md#appendix-a
-smpServerHandshake :: forall c. Transport c => C.APrivateSignKey -> c -> C.KeyPairX25519 -> C.KeyHash -> VersionRangeSMP -> ExceptT TransportError IO (THandleSMP c)
+smpServerHandshake :: forall c. Transport c => C.APrivateSignKey -> c -> C.KeyPairX25519 -> C.KeyHash -> VersionRangeSMP -> ExceptT TransportError IO (THandleSMP c 'TServer)
 smpServerHandshake serverSignKey c (k, pk) kh smpVRange = do
   let th@THandle {params = THandleParams {sessionId}} = smpTHandle c
       sk = C.signX509 serverSignKey $ C.publicToX509 k
@@ -460,47 +484,56 @@ smpServerHandshake serverSignKey c (k, pk) kh smpVRange = do
       | keyHash /= kh ->
           throwE $ TEHandshake IDENTITY
       | v `isCompatible` smpVRange ->
-          pure $ smpThHandle th v pk k'
+          pure $ smpThHandleServer th v pk k'
       | otherwise -> throwE $ TEHandshake VERSION
 
 -- | Client SMP transport handshake.
 --
 -- See https://github.com/simplex-chat/simplexmq/blob/master/protocol/simplex-messaging.md#appendix-a
-smpClientHandshake :: forall c. Transport c => c -> C.KeyPairX25519 -> C.KeyHash -> VersionRangeSMP -> ExceptT TransportError IO (THandleSMP c)
-smpClientHandshake c (k, pk) keyHash@(C.KeyHash kh) smpVRange = do
+smpClientHandshake :: forall c. Transport c => c -> Maybe C.KeyPairX25519 -> C.KeyHash -> VersionRangeSMP -> ExceptT TransportError IO (THandleSMP c 'TClient)
+smpClientHandshake c ks_ keyHash@(C.KeyHash kh) smpVRange = do
   let th@THandle {params = THandleParams {sessionId}} = smpTHandle c
   ServerHandshake {sessionId = sessId, smpVersionRange, authPubKey} <- getHandshake th
   if sessionId /= sessId
     then throwE TEBadSession
     else case smpVersionRange `compatibleVersion` smpVRange of
       Just (Compatible v) -> do
-        sk_ <- forM authPubKey $ \(X.CertificateChain cert, exact) ->
+        ck_ <- forM authPubKey $ \certKey@(X.CertificateChain cert, exact) ->
           liftEitherWith (const $ TEHandshake BAD_AUTH) $ do
             case cert of
               [_leaf, ca] | XV.Fingerprint kh == XV.getFingerprint ca X.HashSHA256 -> pure ()
               _ -> throwError "bad certificate"
             serverKey <- getServerVerifyKey c
             pubKey <- C.verifyX509 serverKey exact
-            C.x509ToPublic (pubKey, []) >>= C.pubKey
-        sendHandshake th $ ClientHandshake {smpVersion = v, keyHash, authPubKey = Just k}
-        pure $ smpThHandle th v pk sk_
+            (,certKey) <$> (C.x509ToPublic (pubKey, []) >>= C.pubKey)
+        sendHandshake th $ ClientHandshake {smpVersion = v, keyHash, authPubKey = fst <$> ks_}
+        pure $ smpThHandleClient th v (snd <$> ks_) ck_
       Nothing -> throwE $ TEHandshake VERSION
 
-smpThHandle :: forall c. THandleSMP c -> VersionSMP -> C.PrivateKeyX25519 -> Maybe C.PublicKeyX25519 -> THandleSMP c
-smpThHandle th@THandle {params} v privKey k_ =
-  -- TODO drop SMP v6: make thAuth non-optional
-  let thAuth = (\k -> THandleAuth {peerPubKey = k, privKey}) <$> k_
-      params' = params {thVersion = v, thAuth, implySessId = v >= authCmdsSMPVersion}
-   in (th :: THandleSMP c) {params = params'}
+smpThHandleServer :: forall c. THandleSMP c 'TServer -> VersionSMP -> C.PrivateKeyX25519 -> Maybe C.PublicKeyX25519 -> THandleSMP c 'TServer
+smpThHandleServer th v pk k_ =
+  let thAuth = THAuthServer {serverPrivKey = pk, sessSecret' = (`C.dh'` pk) <$> k_}
+   in smpThHandle_ th v (Just thAuth)
 
-sendHandshake :: (Transport c, Encoding smp) => THandle v c -> smp -> ExceptT TransportError IO ()
+smpThHandleClient :: forall c. THandleSMP c 'TClient -> VersionSMP -> Maybe C.PrivateKeyX25519 -> Maybe (C.PublicKeyX25519, (X.CertificateChain, X.SignedExact X.PubKey)) -> THandleSMP c 'TClient
+smpThHandleClient th v pk_ ck_ =
+  let thAuth = (\(k, ck) -> THAuthClient {serverPeerPubKey = k, serverCertKey = ck, sessSecret = C.dh' k <$> pk_}) <$> ck_
+   in smpThHandle_ th v thAuth
+
+smpThHandle_ :: forall c p. THandleSMP c p -> VersionSMP -> Maybe (THandleAuth p) -> THandleSMP c p
+smpThHandle_ th@THandle {params} v thAuth =
+  -- TODO drop SMP v6: make thAuth non-optional
+  let params' = params {thVersion = v, thAuth, implySessId = v >= authCmdsSMPVersion}
+   in (th :: THandleSMP c p) {params = params'}
+
+sendHandshake :: (Transport c, Encoding smp) => THandle v c p -> smp -> ExceptT TransportError IO ()
 sendHandshake th = ExceptT . tPutBlock th . smpEncode
 
 -- ignores tail bytes to allow future extensions
-getHandshake :: (Transport c, Encoding smp) => THandle v c -> ExceptT TransportError IO smp
+getHandshake :: (Transport c, Encoding smp) => THandle v c p -> ExceptT TransportError IO smp
 getHandshake th = ExceptT $ (first (\_ -> TEHandshake PARSE) . A.parseOnly smpP =<<) <$> tGetBlock th
 
-smpTHandle :: Transport c => c -> THandleSMP c
+smpTHandle :: Transport c => c -> THandleSMP c p
 smpTHandle c = THandle {connection = c, params}
   where
     params = THandleParams {sessionId = tlsUnique c, blockSize = smpBlockSize, thVersion = VersionSMP 0, thAuth = Nothing, implySessId = False, batch = True}

src/Simplex/Messaging/Transport/Client.hs

@@ -17,6 +17,7 @@ module Simplex.Messaging.Transport.Client
     TransportHost (..),
     TransportHosts (..),
     TransportHosts_ (..),
+    validateCertificateChain
   )
 where
 
@@ -113,12 +114,13 @@ data TransportClientConfig = TransportClientConfig
   { socksProxy :: Maybe SocksProxy,
     tcpKeepAlive :: Maybe KeepAliveOpts,
     logTLSErrors :: Bool,
-    clientCredentials :: Maybe (X.CertificateChain, T.PrivKey)
+    clientCredentials :: Maybe (X.CertificateChain, T.PrivKey),
+    alpn :: Maybe [ALPN]
   }
   deriving (Eq, Show)
 
 defaultTransportClientConfig :: TransportClientConfig
-defaultTransportClientConfig = TransportClientConfig Nothing (Just defaultKeepAliveOpts) True Nothing
+defaultTransportClientConfig = TransportClientConfig Nothing (Just defaultKeepAliveOpts) True Nothing Nothing
 
 clientTransportConfig :: TransportClientConfig -> TransportConfig
 clientTransportConfig TransportClientConfig {logTLSErrors} =
@@ -129,10 +131,10 @@ runTransportClient :: Transport c => TransportClientConfig -> Maybe ByteString -
 runTransportClient = runTLSTransportClient supportedParameters Nothing
 
 runTLSTransportClient :: Transport c => T.Supported -> Maybe XS.CertificateStore -> TransportClientConfig -> Maybe ByteString -> TransportHost -> ServiceName -> Maybe C.KeyHash -> (c -> IO a) -> IO a
-runTLSTransportClient tlsParams caStore_ cfg@TransportClientConfig {socksProxy, tcpKeepAlive, clientCredentials} proxyUsername host port keyHash client = do
+runTLSTransportClient tlsParams caStore_ cfg@TransportClientConfig {socksProxy, tcpKeepAlive, clientCredentials, alpn} proxyUsername host port keyHash client = do
   serverCert <- newEmptyTMVarIO
   let hostName = B.unpack $ strEncode host
-      clientParams = mkTLSClientParams tlsParams caStore_ hostName port keyHash clientCredentials serverCert
+      clientParams = mkTLSClientParams tlsParams caStore_ hostName port keyHash clientCredentials alpn serverCert
       connectTCP = case socksProxy of
         Just proxy -> connectSocksClient proxy proxyUsername $ hostAddr host
         _ -> connectTCPClient hostName
@@ -215,14 +217,15 @@ instance ToJSON SocksProxy where
 instance FromJSON SocksProxy where
   parseJSON = strParseJSON "SocksProxy"
 
-mkTLSClientParams :: T.Supported -> Maybe XS.CertificateStore -> HostName -> ServiceName -> Maybe C.KeyHash -> Maybe (X.CertificateChain, T.PrivKey) -> TMVar X.CertificateChain -> T.ClientParams
-mkTLSClientParams supported caStore_ host port cafp_ clientCreds_ serverCerts =
+mkTLSClientParams :: T.Supported -> Maybe XS.CertificateStore -> HostName -> ServiceName -> Maybe C.KeyHash -> Maybe (X.CertificateChain, T.PrivKey) -> Maybe [ALPN] -> TMVar X.CertificateChain -> T.ClientParams
+mkTLSClientParams supported caStore_ host port cafp_ clientCreds_ alpn_ serverCerts =
   (T.defaultParamsClient host p)
     { T.clientShared = def {T.sharedCAStore = fromMaybe (T.sharedCAStore def) caStore_},
       T.clientHooks =
         def
           { T.onServerCertificate = onServerCert,
-            T.onCertificateRequest = maybe def (const . pure . Just) clientCreds_
+            T.onCertificateRequest = maybe def (const . pure . Just) clientCreds_,
+            T.onSuggestALPN = pure alpn_
           },
       T.clientSupported = supported
     }
@@ -237,7 +240,7 @@ mkTLSClientParams supported caStore_ host port cafp_ clientCreds_ serverCerts =
 validateCertificateChain :: C.KeyHash -> HostName -> ByteString -> X.CertificateChain -> IO [XV.FailedReason]
 validateCertificateChain _ _ _ (X.CertificateChain []) = pure [XV.EmptyChain]
 validateCertificateChain _ _ _ (X.CertificateChain [_]) = pure [XV.EmptyChain]
-validateCertificateChain (C.KeyHash kh) host port cc@(X.CertificateChain sc@[_, caCert]) =
+validateCertificateChain (C.KeyHash kh) host port cc@(X.CertificateChain [_, caCert]) =
   if Fingerprint kh == XV.getFingerprint caCert X.HashSHA256
     then x509validate
     else pure [XV.UnknownCA]
@@ -247,7 +250,7 @@ validateCertificateChain (C.KeyHash kh) host port cc@(X.CertificateChain sc@[_,
       where
         hooks = XV.defaultHooks
         checks = XV.defaultChecks {XV.checkFQHN = False}
-        certStore = XS.makeCertificateStore sc
+        certStore = XS.makeCertificateStore [caCert]
         cache = XV.exceptionValidationCache [] -- we manually check fingerprint only of the identity certificate (ca.crt)
         serviceID = (host, port)
 validateCertificateChain _ _ _ _ = pure [XV.AuthorityTooDeep]

src/Simplex/Messaging/Transport/HTTP2.hs

@@ -16,15 +16,15 @@ import qualified Network.HTTP2.Server as HS
 import Network.Socket (SockAddr (..))
 import qualified Network.TLS as T
 import qualified Network.TLS.Extra as TE
-import Simplex.Messaging.Transport (SessionId, TLS (tlsUniq), Transport (cGet, cPut))
+import Simplex.Messaging.Transport (TLS, Transport (cGet, cPut))
 import Simplex.Messaging.Transport.Buffer
 import qualified System.TimeManager as TI
 
 defaultHTTP2BufferSize :: BufferSize
 defaultHTTP2BufferSize = 32768
 
-withHTTP2 :: BufferSize -> (Config -> SessionId -> IO a) -> TLS -> IO a
-withHTTP2 sz run c = E.bracket (allocHTTP2Config c sz) freeSimpleConfig (`run` tlsUniq c)
+withHTTP2 :: BufferSize -> (Config -> IO a) -> IO () -> TLS -> IO a
+withHTTP2 sz run fin c = E.bracket (allocHTTP2Config c sz) (\cfg -> freeSimpleConfig cfg `E.finally` fin) run
 
 allocHTTP2Config :: TLS -> BufferSize -> IO Config
 allocHTTP2Config c sz = do

src/Simplex/Messaging/Transport/HTTP2/Client.hs

@@ -23,15 +23,20 @@ import qualified Network.TLS as T
 import Numeric.Natural (Natural)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding.String
-import Simplex.Messaging.Transport (SessionId, TLS)
+import Simplex.Messaging.Transport (ALPN, SessionId, TLS (tlsALPN), getServerCerts, getServerVerifyKey, tlsUniq)
 import Simplex.Messaging.Transport.Client (TransportClientConfig (..), TransportHost (..), runTLSTransportClient)
 import Simplex.Messaging.Transport.HTTP2
+import Simplex.Messaging.Util (eitherToMaybe)
 import UnliftIO.STM
 import UnliftIO.Timeout
+import qualified Data.X509 as X
 
 data HTTP2Client = HTTP2Client
   { action :: Maybe (Async HTTP2Response),
     sessionId :: SessionId,
+    sessionALPN :: Maybe ALPN,
+    serverKey :: Maybe C.APublicVerifyKey, -- may not always be a key we control (i.e. APNS with apple-mandated key types)
+    serverCerts :: X.CertificateChain,
     sessionTs :: UTCTime,
     sendReq :: Request -> (Response -> IO HTTP2Response) -> IO HTTP2Response,
     client_ :: HClient
@@ -66,7 +71,7 @@ defaultHTTP2ClientConfig =
   HTTP2ClientConfig
     { qSize = 64,
       connTimeout = 10000000,
-      transportConfig = TransportClientConfig Nothing Nothing True Nothing,
+      transportConfig = TransportClientConfig Nothing Nothing True Nothing Nothing,
       bufferSize = defaultHTTP2BufferSize,
       bodyHeadSize = 16384,
       suportedTLSParams = http2TLSParams
@@ -86,9 +91,10 @@ getVerifiedHTTP2Client proxyUsername host port keyHash caStore config disconnect
 attachHTTP2Client :: HTTP2ClientConfig -> TransportHost -> ServiceName -> IO () -> Int -> TLS -> IO (Either HTTP2ClientError HTTP2Client)
 attachHTTP2Client config host port disconnected bufferSize tls = getVerifiedHTTP2ClientWith config host port disconnected setup
   where
+    setup :: (TLS -> H.Client HTTP2Response) -> IO HTTP2Response
     setup = runHTTP2ClientWith bufferSize host ($ tls)
 
-getVerifiedHTTP2ClientWith :: HTTP2ClientConfig -> TransportHost -> ServiceName -> IO () -> ((SessionId -> H.Client HTTP2Response) -> IO HTTP2Response) -> IO (Either HTTP2ClientError HTTP2Client)
+getVerifiedHTTP2ClientWith :: HTTP2ClientConfig -> TransportHost -> ServiceName -> IO () -> ((TLS -> H.Client HTTP2Response) -> IO HTTP2Response) -> IO (Either HTTP2ClientError HTTP2Client)
 getVerifiedHTTP2ClientWith config host port disconnected setup =
   (atomically mkHTTPS2Client >>= runClient)
     `E.catch` \(e :: IOException) -> pure . Left $ HCIOError e
@@ -104,15 +110,25 @@ getVerifiedHTTP2ClientWith config host port disconnected setup =
       cVar <- newEmptyTMVarIO
       action <- async $ setup (client c cVar) `E.finally` atomically (putTMVar cVar $ Left HCNetworkError)
       c_ <- connTimeout config `timeout` atomically (takeTMVar cVar)
-      pure $ case c_ of
-        Just (Right c') -> Right c' {action = Just action}
-        Just (Left e) -> Left e
-        Nothing -> Left HCNetworkError
+      case c_ of
+        Just (Right c') -> pure $ Right c' {action = Just action}
+        Just (Left e) -> pure $ Left e
+        Nothing -> cancel action $> Left HCNetworkError
 
-    client :: HClient -> TMVar (Either HTTP2ClientError HTTP2Client) -> SessionId -> H.Client HTTP2Response
-    client c cVar sessionId sendReq = do
+    client :: HClient -> TMVar (Either HTTP2ClientError HTTP2Client) -> TLS -> H.Client HTTP2Response
+    client c cVar tls sendReq = do
       sessionTs <- getCurrentTime
-      let c' = HTTP2Client {action = Nothing, client_ = c, sendReq, sessionId, sessionTs}
+      let c' =
+            HTTP2Client
+              { action = Nothing,
+                client_ = c,
+                serverKey = eitherToMaybe $ getServerVerifyKey tls,
+                serverCerts = getServerCerts tls,
+                sendReq,
+                sessionTs,
+                sessionId = tlsUniq tls,
+                sessionALPN = tlsALPN tls
+              }
       atomically $ do
         writeTVar (connected c) True
         putTMVar cVar (Right c')
@@ -154,13 +170,14 @@ sendRequestDirect HTTP2Client {client_ = HClient {config, disconnected}, sendReq
 http2RequestTimeout :: HTTP2ClientConfig -> Maybe Int -> Int
 http2RequestTimeout HTTP2ClientConfig {connTimeout} = maybe connTimeout (connTimeout +)
 
-runHTTP2Client :: forall a. T.Supported -> Maybe XS.CertificateStore -> TransportClientConfig -> BufferSize -> Maybe ByteString -> TransportHost -> ServiceName -> Maybe C.KeyHash -> (SessionId -> H.Client a) -> IO a
+runHTTP2Client :: forall a. T.Supported -> Maybe XS.CertificateStore -> TransportClientConfig -> BufferSize -> Maybe ByteString -> TransportHost -> ServiceName -> Maybe C.KeyHash -> (TLS -> H.Client a) -> IO a
 runHTTP2Client tlsParams caStore tcConfig bufferSize proxyUsername host port keyHash = runHTTP2ClientWith bufferSize host setup
   where
+    setup :: (TLS -> IO a) -> IO a
     setup = runTLSTransportClient tlsParams caStore tcConfig proxyUsername host port keyHash
 
-runHTTP2ClientWith :: forall a. BufferSize -> TransportHost -> ((TLS -> IO a) -> IO a) -> (SessionId -> H.Client a) -> IO a
-runHTTP2ClientWith bufferSize host setup client = setup $ withHTTP2 bufferSize run
+runHTTP2ClientWith :: forall a. BufferSize -> TransportHost -> ((TLS -> IO a) -> IO a) -> (TLS -> H.Client a) -> IO a
+runHTTP2ClientWith bufferSize host setup client = setup $ \tls -> withHTTP2 bufferSize (run tls) (pure ()) tls
   where
-    run :: H.Config -> SessionId -> IO a
-    run cfg sessId = H.run (ClientConfig "https" (strEncode host) 20) cfg $ client sessId
+    run :: TLS -> H.Config -> IO a
+    run tls cfg = H.run (ClientConfig "https" (strEncode host) 20) cfg $ client tls

src/Simplex/Messaging/Transport/HTTP2/Server.hs

@@ -13,14 +13,14 @@ import Network.Socket
 import qualified Network.TLS as T
 import Numeric.Natural (Natural)
 import Simplex.Messaging.Server.Expiration
-import Simplex.Messaging.Transport (SessionId, TLS, closeConnection)
+import Simplex.Messaging.Transport (ALPN, SessionId, TLS, closeConnection, tlsALPN, tlsUniq)
 import Simplex.Messaging.Transport.HTTP2
 import Simplex.Messaging.Transport.Server (TransportServerConfig (..), loadSupportedTLSServerParams, runTransportServer)
 import Simplex.Messaging.Util (threadDelay')
 import UnliftIO (finally)
 import UnliftIO.Concurrent (forkIO, killThread)
 
-type HTTP2ServerFunc = SessionId -> Request -> (Response -> IO ()) -> IO ()
+type HTTP2ServerFunc = SessionId -> Maybe ALPN -> Request -> (Response -> IO ()) -> IO ()
 
 data HTTP2ServerConfig = HTTP2ServerConfig
   { qSize :: Natural,
@@ -37,6 +37,7 @@ data HTTP2ServerConfig = HTTP2ServerConfig
 
 data HTTP2Request = HTTP2Request
   { sessionId :: SessionId,
+    sessionALPN :: Maybe ALPN,
     request :: Request,
     reqBody :: HTTP2Body,
     sendResponse :: Response -> IO ()
@@ -54,32 +55,32 @@ getHTTP2Server HTTP2ServerConfig {qSize, http2Port, bufferSize, bodyHeadSize, se
   started <- newEmptyTMVarIO
   reqQ <- newTBQueueIO qSize
   action <- async $
-    runHTTP2Server started http2Port bufferSize tlsServerParams transportConfig Nothing $ \sessionId r sendResponse -> do
+    runHTTP2Server started http2Port bufferSize tlsServerParams transportConfig Nothing (const $ pure ()) $ \sessionId sessionALPN r sendResponse -> do
       reqBody <- getHTTP2Body r bodyHeadSize
-      atomically $ writeTBQueue reqQ HTTP2Request {sessionId, request = r, reqBody, sendResponse}
+      atomically $ writeTBQueue reqQ HTTP2Request {sessionId, sessionALPN, request = r, reqBody, sendResponse}
   void . atomically $ takeTMVar started
   pure HTTP2Server {action, reqQ}
 
 closeHTTP2Server :: HTTP2Server -> IO ()
 closeHTTP2Server = uninterruptibleCancel . action
 
-runHTTP2Server :: TMVar Bool -> ServiceName -> BufferSize -> T.ServerParams -> TransportServerConfig -> Maybe ExpirationConfig -> HTTP2ServerFunc -> IO ()
-runHTTP2Server started port bufferSize serverParams transportConfig expCfg_ = runHTTP2ServerWith_ expCfg_ bufferSize setup
+runHTTP2Server :: TMVar Bool -> ServiceName -> BufferSize -> T.ServerParams -> TransportServerConfig -> Maybe ExpirationConfig -> (SessionId -> IO ()) -> HTTP2ServerFunc -> IO ()
+runHTTP2Server started port bufferSize serverParams transportConfig expCfg_ clientFinished = runHTTP2ServerWith_ expCfg_ clientFinished bufferSize setup
   where
     setup = runTransportServer started port serverParams transportConfig
 
 runHTTP2ServerWith :: BufferSize -> ((TLS -> IO ()) -> a) -> HTTP2ServerFunc -> a
-runHTTP2ServerWith = runHTTP2ServerWith_ Nothing
+runHTTP2ServerWith = runHTTP2ServerWith_ Nothing (\_sessId -> pure ())
 
-runHTTP2ServerWith_ :: Maybe ExpirationConfig -> BufferSize -> ((TLS -> IO ()) -> a) -> HTTP2ServerFunc -> a
-runHTTP2ServerWith_ expCfg_ bufferSize setup http2Server = setup $ \tls -> do
+runHTTP2ServerWith_ :: Maybe ExpirationConfig -> (SessionId -> IO ()) -> BufferSize -> ((TLS -> IO ()) -> a) -> HTTP2ServerFunc -> a
+runHTTP2ServerWith_ expCfg_ clientFinished bufferSize setup http2Server = setup $ \tls -> do
   activeAt <- newTVarIO =<< getSystemTime
   tid_ <- mapM (forkIO . expireInactiveClient tls activeAt) expCfg_
-  withHTTP2 bufferSize (run activeAt) tls `finally` mapM_ killThread tid_
+  withHTTP2 bufferSize (run tls activeAt) (clientFinished $ tlsUniq tls) tls `finally` mapM_ killThread tid_
   where
-    run activeAt cfg sessId = H.run cfg $ \req _aux sendResp -> do
+    run tls activeAt cfg = H.run cfg $ \req _aux sendResp -> do
       getSystemTime >>= atomically . writeTVar activeAt
-      http2Server sessId req (`sendResp` [])
+      http2Server (tlsUniq tls) (tlsALPN tls) req (`sendResp` [])
     expireInactiveClient tls activeAt expCfg = loop
       where
         loop = do

src/Simplex/Messaging/Transport/Server.hs

@@ -49,7 +49,8 @@ import UnliftIO.STM
 data TransportServerConfig = TransportServerConfig
   { logTLSErrors :: Bool,
     tlsSetupTimeout :: Int,
-    transportTimeout :: Int
+    transportTimeout :: Int,
+    alpn :: Maybe [ALPN]
   }
   deriving (Eq, Show)
 
@@ -58,7 +59,8 @@ defaultTransportServerConfig =
   TransportServerConfig
     { logTLSErrors = True,
       tlsSetupTimeout = 60000000,
-      transportTimeout = 40000000
+      transportTimeout = 40000000,
+      alpn = Nothing
     }
 
 serverTransportConfig :: TransportServerConfig -> TransportConfig
@@ -114,7 +116,7 @@ runTCPServerSocket (accepted, gracefullyClosed, clients) started getSocket serve
     forever . E.bracketOnError (accept sock) (close . fst) $ \(conn, _peer) -> do
       cId <- atomically $ stateTVar accepted $ \cId -> let cId' = cId + 1 in cId `seq` (cId', cId')
       let closeConn _ = do
-            atomically $ modifyTVar' clients $ IM.delete cId 
+            atomically $ modifyTVar' clients $ IM.delete cId
             gracefulClose conn 5000 `catchAll_` pure () -- catchAll_ is needed here in case the connection was closed earlier
             atomically $ modifyTVar' gracefullyClosed (+1)
       tId <- mkWeakThreadId =<< server conn `forkFinally` closeConn

tests/AgentTests.hs

@@ -13,7 +13,7 @@ module AgentTests (agentTests) where
 
 import AgentTests.ConnectionRequestTests
 import AgentTests.DoubleRatchetTests (doubleRatchetTests)
-import AgentTests.FunctionalAPITests (functionalAPITests, pattern Msg, pattern Msg')
+import AgentTests.FunctionalAPITests (functionalAPITests, inAnyOrder, pattern Msg, pattern Msg')
 import AgentTests.MigrationTests (migrationTests)
 import AgentTests.NotificationTests (notificationTests)
 import AgentTests.SQLiteTests (storeTests)
@@ -194,8 +194,8 @@ pqMatrix2_ pqInv _ smpTest test = do
 
 pqMatrix3 ::
   HasCallStack =>
-  TProxy c -> 
-  (HasCallStack => (c -> c -> c -> IO ()) -> Expectation) -> 
+  TProxy c ->
+  (HasCallStack => (c -> c -> c -> IO ()) -> Expectation) ->
   (HasCallStack => (c, InitialKeys) -> (c, PQSupport) -> (c, PQSupport) -> IO ()) ->
   Spec
 pqMatrix3 _ smpTest test = do
@@ -452,7 +452,7 @@ testServerConnectionAfterError t _ = do
   where
     server = SMPServer "localhost" testPort2 testKeyHash
     withServer test' = withSmpServerStoreLogOn (ATransport t) testPort2 (const test') `shouldReturn` ()
-    withAgent1 = withAgent agentTestPort testDB 0 
+    withAgent1 = withAgent agentTestPort testDB 0
     withAgent2 = withAgent agentTestPort2 testDB2 10
     withAgent :: String -> FilePath -> Int -> (c -> IO a) -> IO a
     withAgent agentPort agentDB initClientId = withSmpAgentThreadOn_ (ATransport t) (agentPort, testPort2, agentDB) initClientId (pure ()) . const . testSMPAgentClientOn agentPort
@@ -554,7 +554,11 @@ testResumeDeliveryQuotaExceeded _ alice bob = do
   alice #:# "the last message not sent"
   bob <#= \case ("", "alice", Msg "message 4") -> True; _ -> False
   bob #: ("4", "alice", "ACK 7") #> ("4", "alice", OK)
-  alice <# ("", "bob", SENT 8)
+  inAnyOrder
+      (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)

tests/AgentTests/NotificationTests.hs

@@ -17,7 +17,10 @@ import AgentTests.FunctionalAPITests
     createConnection,
     exchangeGreetingsMsgId,
     get,
-    getSMPAgentClient',
+    withAgent,
+    withAgentClients2,
+    withAgentClientsCfgServers2,
+    withAgentClients3,
     joinConnection,
     makeConnection,
     nGet,
@@ -42,15 +45,15 @@ import Control.Monad.Trans.Except
 import qualified Data.Aeson as J
 import qualified Data.Aeson.Types as JT
 import Data.Bifunctor (bimap, first)
+import qualified Data.ByteString.Base64.URL as U
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
 import Data.Text.Encoding (encodeUtf8)
 import NtfClient
-import SMPAgentClient (agentCfg, initAgentServers, initAgentServers2, testDB, testDB2, testDB3, testNtfServer, testNtfServer2)
+import SMPAgentClient (agentCfg, initAgentServers, initAgentServers2, testDB, testDB2, testNtfServer, testNtfServer2)
 import SMPClient (cfg, cfgV7, testPort, testPort2, testStoreLogFile2, withSmpServer, withSmpServerConfigOn, withSmpServerStoreLogOn)
 import Simplex.Messaging.Agent hiding (createConnection, joinConnection, sendMessage)
 import Simplex.Messaging.Agent.Client (ProtocolTestFailure (..), ProtocolTestStep (..), withStore')
-import qualified Simplex.Messaging.Encoding.Base64.URL as U
 import Simplex.Messaging.Agent.Env.SQLite (AgentConfig, Env (..), InitialAgentServers)
 import Simplex.Messaging.Agent.Protocol hiding (CON, CONF, INFO)
 import Simplex.Messaging.Agent.Store.SQLite (getSavedNtfToken)
@@ -165,8 +168,7 @@ runNtfTestCfg t smpCfg ntfCfg aCfg bCfg runTest =
 
 testNotificationToken :: APNSMockServer -> IO ()
 testNotificationToken APNSMockServer {apnsQ} = do
-  a <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-  runRight_ $ do
+  withAgent 1 agentCfg initAgentServers testDB $ \a -> runRight_ $ do
     let tkn = DeviceToken PPApnsTest "abcd"
     NTRegistered <- registerNtfToken a tkn NMPeriodic
     APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData}, sendApnsResponse} <-
@@ -179,7 +181,7 @@ testNotificationToken APNSMockServer {apnsQ} = do
     deleteNtfToken a tkn
     -- agent deleted this token
     Left (CMD PROHIBITED) <- tryE $ checkNtfToken a tkn
-    liftIO $ disposeAgentClient a
+    pure ()
 
 (.->) :: J.Value -> J.Key -> ExceptT AgentErrorType IO ByteString
 v .-> key = do
@@ -193,8 +195,7 @@ testNtfTokenRepeatRegistration :: APNSMockServer -> IO ()
 testNtfTokenRepeatRegistration APNSMockServer {apnsQ} = do
   -- setLogLevel LogError -- LogDebug
   -- withGlobalLogging logCfg $ do
-  a <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-  runRight_ $ do
+  withAgent 1 agentCfg initAgentServers testDB $ \a -> runRight_ $ do
     let tkn = DeviceToken PPApnsTest "abcd"
     NTRegistered <- registerNtfToken a tkn NMPeriodic
     APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData}, sendApnsResponse} <-
@@ -211,15 +212,13 @@ testNtfTokenRepeatRegistration APNSMockServer {apnsQ} = do
     -- can still use the first verification code, it is the same after decryption
     verifyNtfToken a tkn nonce verification
     NTActive <- checkNtfToken a tkn
-    liftIO $ disposeAgentClient a
+    pure ()
 
 testNtfTokenSecondRegistration :: APNSMockServer -> IO ()
-testNtfTokenSecondRegistration APNSMockServer {apnsQ} = do
+testNtfTokenSecondRegistration APNSMockServer {apnsQ} =
   -- setLogLevel LogError -- LogDebug
   -- withGlobalLogging logCfg $ do
-  a <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-  a' <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
-  runRight_ $ do
+  withAgentClients2 $ \a a' -> runRight_ $ do
     let tkn = DeviceToken PPApnsTest "abcd"
     NTRegistered <- registerNtfToken a tkn NMPeriodic
     APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData}, sendApnsResponse} <-
@@ -248,37 +247,34 @@ testNtfTokenSecondRegistration APNSMockServer {apnsQ} = do
     -- and the second is active
     NTActive <- checkNtfToken a' tkn
     pure ()
-  disposeAgentClient a
-  disposeAgentClient a'
 
 testNtfTokenServerRestart :: ATransport -> APNSMockServer -> IO ()
 testNtfTokenServerRestart t APNSMockServer {apnsQ} = do
-  a <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
   let tkn = DeviceToken PPApnsTest "abcd"
-  ntfData <- withNtfServer t . runRight $ do
-    NTRegistered <- registerNtfToken a tkn NMPeriodic
-    APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData}, sendApnsResponse} <-
-      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
+  ntfData <- withAgent 1 agentCfg initAgentServers testDB $ \a ->
+    withNtfServer t . runRight $ do
+      NTRegistered <- registerNtfToken a tkn NMPeriodic
+      APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData}, sendApnsResponse} <-
+        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
   threadDelay 1000000
-  disposeAgentClient a
-  a' <- getSMPAgentClient' 2 agentCfg initAgentServers testDB
-  -- server stopped before token is verified, so now the attempt to verify it will return AUTH error but re-register token,
-  -- so that repeat verification happens without restarting the clients, when notification arrives
-  withNtfServer t . runRight_ $ do
-    verification <- ntfData .-> "verification"
-    nonce <- C.cbNonce <$> ntfData .-> "nonce"
-    Left (NTF AUTH) <- tryE $ verifyNtfToken a' tkn nonce verification
-    APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData'}, sendApnsResponse = sendApnsResponse'} <-
-      atomically $ readTBQueue apnsQ
-    verification' <- ntfData' .-> "verification"
-    nonce' <- C.cbNonce <$> ntfData' .-> "nonce"
-    liftIO $ sendApnsResponse' APNSRespOk
-    verifyNtfToken a' tkn nonce' verification'
-    NTActive <- checkNtfToken a' tkn
-    liftIO $ disposeAgentClient a'
+  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,
+    -- so that repeat verification happens without restarting the clients, when notification arrives
+    withNtfServer t . runRight_ $ do
+      verification <- ntfData .-> "verification"
+      nonce <- C.cbNonce <$> ntfData .-> "nonce"
+      Left (NTF AUTH) <- tryE $ verifyNtfToken a' tkn nonce verification
+      APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData'}, sendApnsResponse = sendApnsResponse'} <-
+        atomically $ readTBQueue apnsQ
+      verification' <- ntfData' .-> "verification"
+      nonce' <- C.cbNonce <$> ntfData' .-> "nonce"
+      liftIO $ sendApnsResponse' APNSRespOk
+      verifyNtfToken a' tkn nonce' verification'
+      NTActive <- checkNtfToken a' tkn
+      pure ()
 
 getTestNtfTokenPort :: AgentClient -> AE String
 getTestNtfTokenPort a =
@@ -289,66 +285,62 @@ getTestNtfTokenPort a =
 testNtfTokenMultipleServers :: ATransport -> APNSMockServer -> IO ()
 testNtfTokenMultipleServers t APNSMockServer {apnsQ} = do
   let tkn = DeviceToken PPApnsTest "abcd"
-  a <- getSMPAgentClient' 1 agentCfg initAgentServers2 testDB
-  withNtfServerThreadOn t ntfTestPort $ \ntf ->
-    withNtfServerThreadOn t ntfTestPort2 $ \ntf2 -> runRight_ $ do
-      -- register a new token, the agent picks a server and stores its choice
-      NTRegistered <- registerNtfToken a tkn NMPeriodic
-      APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData}, sendApnsResponse} <-
-        atomically $ readTBQueue apnsQ
-      verification <- ntfData .-> "verification"
-      nonce <- C.cbNonce <$> ntfData .-> "nonce"
-      liftIO $ sendApnsResponse APNSRespOk
-      verifyNtfToken a tkn nonce verification
-      NTActive <- checkNtfToken a tkn
-      -- shut down the "other" server
-      port <- getTestNtfTokenPort a
-      liftIO . killThread $ if port == ntfTestPort then ntf2 else ntf
-      -- still works
-      NTActive <- checkNtfToken a tkn
-      liftIO . killThread $ if port == ntfTestPort then ntf else ntf2
-      -- negative test, the correct server is now gone
-      Left _ <- tryError (checkNtfToken a tkn)
-      pure ()
+  withAgent 1 agentCfg initAgentServers2 testDB $ \a ->
+    withNtfServerThreadOn t ntfTestPort $ \ntf ->
+      withNtfServerThreadOn t ntfTestPort2 $ \ntf2 -> runRight_ $ do
+        -- register a new token, the agent picks a server and stores its choice
+        NTRegistered <- registerNtfToken a tkn NMPeriodic
+        APNSMockRequest {notification = APNSNotification {aps = APNSBackground _, notificationData = Just ntfData}, sendApnsResponse} <-
+          atomically $ readTBQueue apnsQ
+        verification <- ntfData .-> "verification"
+        nonce <- C.cbNonce <$> ntfData .-> "nonce"
+        liftIO $ sendApnsResponse APNSRespOk
+        verifyNtfToken a tkn nonce verification
+        NTActive <- checkNtfToken a tkn
+        -- shut down the "other" server
+        port <- getTestNtfTokenPort a
+        liftIO . killThread $ if port == ntfTestPort then ntf2 else ntf
+        -- still works
+        NTActive <- checkNtfToken a tkn
+        liftIO . killThread $ if port == ntfTestPort then ntf else ntf2
+        -- negative test, the correct server is now gone
+        Left _ <- tryError (checkNtfToken a tkn)
+        pure ()
 
 testNtfTokenChangeServers :: ATransport -> APNSMockServer -> IO ()
 testNtfTokenChangeServers t APNSMockServer {apnsQ} =
   withNtfServerThreadOn t ntfTestPort $ \ntf -> do
-    tkn1 <- runRight $ do
-      a <- liftIO $ getSMPAgentClient' 1 agentCfg initAgentServers testDB
+    tkn1 <- withAgent 1 agentCfg initAgentServers testDB $ \a -> runRight $ do
       tkn <- registerTestToken a "abcd" NMInstant apnsQ
       NTActive <- checkNtfToken a tkn
       liftIO $ setNtfServers a [testNtfServer2]
       NTActive <- checkNtfToken a tkn -- still works on old server
-      liftIO $ disposeAgentClient a
       pure tkn
 
     threadDelay 1000000
 
-    a <- getSMPAgentClient' 2 agentCfg initAgentServers testDB
-    runRight_ $ do
-      getTestNtfTokenPort a >>= \port -> liftIO $ port `shouldBe` ntfTestPort
-      NTActive <- checkNtfToken a tkn1
-      liftIO $ setNtfServers a [testNtfServer2] -- just change configured server list
-      getTestNtfTokenPort a >>= \port -> liftIO $ port `shouldBe` ntfTestPort -- not yet changed
-      -- trigger token replace
-      tkn2 <- registerTestToken a "xyzw" NMInstant apnsQ
-      getTestNtfTokenPort a >>= \port -> liftIO $ port `shouldBe` ntfTestPort -- not yet changed
-      deleteNtfToken a tkn2 -- force server switch
-      Left BROKER {brokerErr = NETWORK} <- tryError $ registerTestToken a "qwer" NMInstant apnsQ -- ok, it's down for now
-      getTestNtfTokenPort a >>= \port2 -> liftIO $ port2 `shouldBe` ntfTestPort2 -- but the token got updated
-    killThread ntf
-    withNtfServerOn t ntfTestPort2 $ runRight_ $ do
-      tkn <- registerTestToken a "qwer" NMInstant apnsQ
-      checkNtfToken a tkn >>= \r -> liftIO $ r `shouldBe` NTActive
+    withAgent 2 agentCfg initAgentServers testDB $ \a -> do
+      runRight_ $ do
+        getTestNtfTokenPort a >>= \port -> liftIO $ port `shouldBe` ntfTestPort
+        NTActive <- checkNtfToken a tkn1
+        liftIO $ setNtfServers a [testNtfServer2] -- just change configured server list
+        getTestNtfTokenPort a >>= \port -> liftIO $ port `shouldBe` ntfTestPort -- not yet changed
+        -- trigger token replace
+        tkn2 <- registerTestToken a "xyzw" NMInstant apnsQ
+        getTestNtfTokenPort a >>= \port -> liftIO $ port `shouldBe` ntfTestPort -- not yet changed
+        deleteNtfToken a tkn2 -- force server switch
+        Left BROKER {brokerErr = NETWORK} <- tryError $ registerTestToken a "qwer" NMInstant apnsQ -- ok, it's down for now
+        getTestNtfTokenPort a >>= \port2 -> liftIO $ port2 `shouldBe` ntfTestPort2 -- but the token got updated
+      killThread ntf
+      withNtfServerOn t ntfTestPort2 $ runRight_ $ do
+        tkn <- registerTestToken a "qwer" NMInstant apnsQ
+        checkNtfToken a tkn >>= \r -> liftIO $ r `shouldBe` NTActive
 
 testRunNTFServerTests :: ATransport -> NtfServer -> IO (Maybe ProtocolTestFailure)
 testRunNTFServerTests t srv =
-  withNtfServerThreadOn t ntfTestPort $ \ntf -> do
-    a <- liftIO $ getSMPAgentClient' 1 agentCfg initAgentServers testDB
-    r <- testProtocolServer a 1 $ ProtoServerWithAuth srv Nothing
-    killThread ntf
-    pure r
+  withNtfServerOn t ntfTestPort $
+    withAgent 1 agentCfg initAgentServers testDB $ \a ->
+      testProtocolServer a 1 $ ProtoServerWithAuth srv Nothing
 
 testNotificationSubscriptionExistingConnection :: APNSMockServer -> AgentClient -> AgentClient -> IO ()
 testNotificationSubscriptionExistingConnection APNSMockServer {apnsQ} alice@AgentClient {agentEnv = Env {config = aliceCfg}} bob = do
@@ -383,11 +375,9 @@ testNotificationSubscriptionExistingConnection APNSMockServer {apnsQ} alice@Agen
   Left (CMD PROHIBITED) <- runExceptT $ getNotificationMessage alice nonce message
 
   -- aliceNtf client doesn't have subscription and is allowed to get notification message
-  aliceNtf <- getSMPAgentClient' 3 aliceCfg initAgentServers testDB
-  runRight_ $ do
+  withAgent 3 aliceCfg initAgentServers testDB $ \aliceNtf -> runRight_ $ do
     (_, [SMPMsgMeta {msgFlags = MsgFlags True}]) <- getNotificationMessage aliceNtf nonce message
     pure ()
-  disposeAgentClient aliceNtf
 
   runRight_ $ do
     get alice =##> \case ("", c, Msg "hello") -> c == bobId; _ -> False
@@ -459,10 +449,8 @@ registerTestToken a token mode apnsQ = do
   pure tkn
 
 testChangeNotificationsMode :: APNSMockServer -> IO ()
-testChangeNotificationsMode APNSMockServer {apnsQ} = do
-  alice <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-  bob <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
-  runRight_ $ do
+testChangeNotificationsMode APNSMockServer {apnsQ} =
+  withAgentClients2 $ \alice bob -> runRight_ $ do
     -- establish connection
     (bobId, qInfo) <- createConnection alice 1 True SCMInvitation Nothing SMSubscribe
     aliceId <- joinConnection bob 1 True qInfo "bob's connInfo" SMSubscribe
@@ -518,17 +506,13 @@ testChangeNotificationsMode APNSMockServer {apnsQ} = do
     ackMessage alice bobId (baseId + 5) Nothing
     -- no notifications should follow
     noNotification apnsQ
-  disposeAgentClient alice
-  disposeAgentClient bob
   where
     baseId = 3
     msgId = subtract baseId
 
 testChangeToken :: APNSMockServer -> IO ()
-testChangeToken APNSMockServer {apnsQ} = do
-  alice <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-  bob <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
-  (aliceId, bobId) <- runRight $ do
+testChangeToken APNSMockServer {apnsQ} = withAgent 1 agentCfg initAgentServers testDB2 $ \bob -> do
+  (aliceId, bobId) <- withAgent 2 agentCfg initAgentServers testDB $ \alice -> runRight $ do
     -- establish connection
     (bobId, qInfo) <- createConnection alice 1 True SCMInvitation Nothing SMSubscribe
     aliceId <- joinConnection bob 1 True qInfo "bob's connInfo" SMSubscribe
@@ -547,10 +531,8 @@ testChangeToken APNSMockServer {apnsQ} = do
     get alice =##> \case ("", c, Msg "hello") -> c == bobId; _ -> False
     ackMessage alice bobId (baseId + 1) Nothing
     pure (aliceId, bobId)
-  disposeAgentClient alice
 
-  alice1 <- getSMPAgentClient' 3 agentCfg initAgentServers testDB
-  runRight_ $ do
+  withAgent 3 agentCfg initAgentServers testDB $ \alice1 -> runRight_ $ do
     subscribeConnection alice1 bobId
     -- change notification token
     void $ registerTestToken alice1 "bcde" NMInstant apnsQ
@@ -563,16 +545,12 @@ testChangeToken APNSMockServer {apnsQ} = do
     ackMessage alice1 bobId (baseId + 2) Nothing
     -- no notifications should follow
     noNotification apnsQ
-  disposeAgentClient alice1
-  disposeAgentClient bob
   where
     baseId = 3
     msgId = subtract baseId
 
 testNotificationsStoreLog :: ATransport -> APNSMockServer -> IO ()
-testNotificationsStoreLog t APNSMockServer {apnsQ} = do
-  alice <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-  bob <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
+testNotificationsStoreLog t APNSMockServer {apnsQ} = withAgentClients2 $ \alice bob -> do
   (aliceId, bobId) <- withNtfServerStoreLog t $ \threadId -> runRight $ do
     (aliceId, bobId) <- makeConnection alice bob
     _ <- registerTestToken alice "abcd" NMInstant apnsQ
@@ -594,13 +572,9 @@ testNotificationsStoreLog t APNSMockServer {apnsQ} = do
     void $ messageNotificationData alice apnsQ
     get alice =##> \case ("", c, Msg "hello again") -> c == bobId; _ -> False
     liftIO $ killThread threadId
-  disposeAgentClient alice
-  disposeAgentClient bob
 
 testNotificationsSMPRestart :: ATransport -> APNSMockServer -> IO ()
-testNotificationsSMPRestart t APNSMockServer {apnsQ} = do
-  alice <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-  bob <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
+testNotificationsSMPRestart t APNSMockServer {apnsQ} = withAgentClients2 $ \alice bob -> do
   (aliceId, bobId) <- withSmpServerStoreLogOn t testPort $ \threadId -> runRight $ do
     (aliceId, bobId) <- makeConnection alice bob
     _ <- registerTestToken alice "abcd" NMInstant apnsQ
@@ -626,49 +600,44 @@ testNotificationsSMPRestart t APNSMockServer {apnsQ} = do
     _ <- messageNotificationData alice apnsQ
     get alice =##> \case ("", c, Msg "hello again") -> c == bobId; _ -> False
     liftIO $ killThread threadId
-  disposeAgentClient alice
-  disposeAgentClient bob
 
 testNotificationsSMPRestartBatch :: Int -> ATransport -> APNSMockServer -> IO ()
-testNotificationsSMPRestartBatch n t APNSMockServer {apnsQ} = do
-  a <- getSMPAgentClient' 1 agentCfg initAgentServers2 testDB
-  b <- getSMPAgentClient' 2 agentCfg initAgentServers2 testDB2
-  threadDelay 1000000
-  conns <- runServers $ do
-    conns <- replicateM (n :: Int) $ makeConnection a b
-    _ <- registerTestToken a "abcd" NMInstant apnsQ
-    liftIO $ threadDelay 5000000
-    forM_ conns $ \(aliceId, bobId) -> do
-      msgId <- sendMessage b aliceId (SMP.MsgFlags True) "hello"
-      get b ##> ("", aliceId, SENT msgId)
-      void $ messageNotificationData a apnsQ
-      get a =##> \case ("", c, Msg "hello") -> c == bobId; _ -> False
-      ackMessage a bobId msgId Nothing
-    pure conns
+testNotificationsSMPRestartBatch n t APNSMockServer {apnsQ} =
+  withAgentClientsCfgServers2 agentCfg agentCfg initAgentServers2 $ \a b -> do
+    threadDelay 1000000
+    conns <- runServers $ do
+      conns <- replicateM (n :: Int) $ makeConnection a b
+      _ <- registerTestToken a "abcd" NMInstant apnsQ
+      liftIO $ threadDelay 5000000
+      forM_ conns $ \(aliceId, bobId) -> do
+        msgId <- sendMessage b aliceId (SMP.MsgFlags True) "hello"
+        get b ##> ("", aliceId, SENT msgId)
+        void $ messageNotificationData a apnsQ
+        get a =##> \case ("", c, Msg "hello") -> c == bobId; _ -> False
+        ackMessage a bobId msgId Nothing
+      pure conns
 
-  runRight_ @AgentErrorType $ do
-    ("", "", DOWN _ bcs1) <- nGet a
-    ("", "", DOWN _ bcs2) <- nGet a
-    liftIO $ length (bcs1 <> bcs2) `shouldBe` length conns
-    ("", "", DOWN _ acs1) <- nGet b
-    ("", "", DOWN _ acs2) <- nGet b
-    liftIO $ length (acs1 <> acs2) `shouldBe` length conns
+    runRight_ @AgentErrorType $ do
+      ("", "", DOWN _ bcs1) <- nGet a
+      ("", "", DOWN _ bcs2) <- nGet a
+      liftIO $ length (bcs1 <> bcs2) `shouldBe` length conns
+      ("", "", DOWN _ acs1) <- nGet b
+      ("", "", DOWN _ acs2) <- nGet b
+      liftIO $ length (acs1 <> acs2) `shouldBe` length conns
 
-  runServers $ do
-    ("", "", UP _ bcs1) <- nGet a
-    ("", "", UP _ bcs2) <- nGet a
-    liftIO $ length (bcs1 <> bcs2) `shouldBe` length conns
-    ("", "", UP _ acs1) <- nGet b
-    ("", "", UP _ acs2) <- nGet b
-    liftIO $ length (acs1 <> acs2) `shouldBe` length conns
-    liftIO $ threadDelay 1500000
-    forM_ conns $ \(aliceId, bobId) -> do
-      msgId <- sendMessage b aliceId (SMP.MsgFlags True) "hello again"
-      get b ##> ("", aliceId, SENT msgId)
-      _ <- messageNotificationData a apnsQ
-      get a =##> \case ("", c, Msg "hello again") -> c == bobId; _ -> False
-  disposeAgentClient a
-  disposeAgentClient b
+    runServers $ do
+      ("", "", UP _ bcs1) <- nGet a
+      ("", "", UP _ bcs2) <- nGet a
+      liftIO $ length (bcs1 <> bcs2) `shouldBe` length conns
+      ("", "", UP _ acs1) <- nGet b
+      ("", "", UP _ acs2) <- nGet b
+      liftIO $ length (acs1 <> acs2) `shouldBe` length conns
+      liftIO $ threadDelay 1500000
+      forM_ conns $ \(aliceId, bobId) -> do
+        msgId <- sendMessage b aliceId (SMP.MsgFlags True) "hello again"
+        get b ##> ("", aliceId, SENT msgId)
+        _ <- messageNotificationData a apnsQ
+        get a =##> \case ("", c, Msg "hello again") -> c == bobId; _ -> False
   where
     runServers :: ExceptT AgentErrorType IO a -> IO a
     runServers a = do
@@ -679,10 +648,8 @@ testNotificationsSMPRestartBatch n t APNSMockServer {apnsQ} = do
         pure res
 
 testSwitchNotifications :: InitialAgentServers -> APNSMockServer -> IO ()
-testSwitchNotifications servers APNSMockServer {apnsQ} = do
-  a <- getSMPAgentClient' 1 agentCfg servers testDB
-  b <- getSMPAgentClient' 2 agentCfg servers testDB2
-  runRight_ $ do
+testSwitchNotifications servers APNSMockServer {apnsQ} =
+  withAgentClientsCfgServers2 agentCfg agentCfg servers $ \a b -> runRight_ $ do
     (aId, bId) <- makeConnection a b
     exchangeGreetingsMsgId 4 a bId b aId
     _ <- registerTestToken a "abcd" NMInstant apnsQ
@@ -698,15 +665,10 @@ testSwitchNotifications servers APNSMockServer {apnsQ} = do
     switchComplete a bId b aId
     liftIO $ threadDelay 500000
     testMessage "hello again"
-  disposeAgentClient a
-  disposeAgentClient b
 
 testNotificationsOldToken :: APNSMockServer -> IO ()
-testNotificationsOldToken APNSMockServer {apnsQ} = do
-  a <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-  b <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
-  c <- getSMPAgentClient' 3 agentCfg initAgentServers testDB3
-  runRight_ $ do
+testNotificationsOldToken APNSMockServer {apnsQ} =
+  withAgentClients3 $ \a b c -> runRight_ $ do
     (abId, baId) <- makeConnection a b
     let testMessageAB = testMessage_ apnsQ a abId b baId
     _ <- registerTestToken a "abcd" NMInstant apnsQ
@@ -722,16 +684,10 @@ testNotificationsOldToken APNSMockServer {apnsQ} = do
     (acId, caId) <- makeConnection a c
     let testMessageAC = testMessage_ apnsQ a acId c caId
     testMessageAC "greetings"
-  disposeAgentClient a
-  disposeAgentClient b
-  disposeAgentClient c
 
 testNotificationsNewToken :: APNSMockServer -> ThreadId -> IO ()
-testNotificationsNewToken APNSMockServer {apnsQ} oldNtf = do
-  a <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-  b <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
-  c <- getSMPAgentClient' 3 agentCfg initAgentServers testDB3
-  runRight_ $ do
+testNotificationsNewToken APNSMockServer {apnsQ} oldNtf =
+  withAgentClients3 $ \a b c -> runRight_ $ do
     (abId, baId) <- makeConnection a b
     let testMessageAB = testMessage_ apnsQ a abId b baId
     tkn <- registerTestToken a "abcd" NMInstant apnsQ
@@ -750,9 +706,6 @@ testNotificationsNewToken APNSMockServer {apnsQ} oldNtf = do
     (acId, caId) <- makeConnection a c
     let testMessageAC = testMessage_ apnsQ a acId c caId
     testMessageAC "greetings"
-  disposeAgentClient a
-  disposeAgentClient b
-  disposeAgentClient c
 
 testMessage_ :: HasCallStack => TBQueue APNSMockRequest -> AgentClient -> ConnId -> AgentClient -> ConnId -> SMP.MsgBody -> ExceptT AgentErrorType IO ()
 testMessage_ apnsQ a aId b bId msg = do

tests/CoreTests/BatchingTests.hs

@@ -1,7 +1,9 @@
+{-# LANGUAGE DataKinds #-}
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE TupleSections #-}
+{-# LANGUAGE TypeApplications #-}
 
 module CoreTests.BatchingTests (batchingTests) where
 
@@ -11,6 +13,9 @@ import Crypto.Random (ChaChaDRG)
 import qualified Data.ByteString as B
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.List.NonEmpty as L
+import qualified Data.X509 as X
+import qualified Data.X509.CertificateStore as XS
+import qualified Data.X509.File as XF
 import Simplex.Messaging.Client
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Protocol
@@ -276,12 +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
@@ -306,15 +311,15 @@ 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
+testTHandleParams :: VersionSMP -> ByteString -> THandleParams SMPVersion 'TClient
 testTHandleParams v sessionId =
   THandleParams
     { sessionId,
@@ -325,11 +330,16 @@ testTHandleParams v sessionId =
       batch = True
     }
 
-testTHandleAuth :: VersionSMP -> TVar ChaChaDRG -> C.APublicAuthKey -> IO (Maybe THandleAuth)
-testTHandleAuth v g (C.APublicAuthKey a k) = case a of
+testTHandleAuth :: VersionSMP -> TVar ChaChaDRG -> C.APublicAuthKey -> IO (Maybe (THandleAuth 'TClient))
+testTHandleAuth v g (C.APublicAuthKey a serverPeerPubKey) = case a of
   C.SX25519 | v >= authCmdsSMPVersion -> do
-    (_, privKey) <- atomically $ C.generateKeyPair g
-    pure $ Just THandleAuth {peerPubKey = k, privKey}
+    ca <- head <$> XS.readCertificates "tests/fixtures/ca.crt"
+    serverCert <- head <$> XS.readCertificates "tests/fixtures/server.crt"
+    serverKey <- head <$> XF.readKeyFile "tests/fixtures/server.key"
+    signKey <- either error pure $ C.x509ToPrivate (serverKey, []) >>= C.privKey @C.APrivateSignKey
+    (serverAuthPub, _) <- atomically $ C.generateKeyPair @'C.X25519 g
+    let serverCertKey = (X.CertificateChain [serverCert, ca], C.signX509 signKey $ C.toPubKey C.publicToX509 serverAuthPub)
+    pure $ Just THAuthClient {serverPeerPubKey, serverCertKey, sessSecret = Nothing}
   _ -> pure Nothing
 
 randomSENDCmd :: ProtocolClient SMPVersion ErrorType BrokerMsg -> Int -> IO (PCTransmission ErrorType BrokerMsg)

tests/CoreTests/CryptoTests.hs

@@ -16,9 +16,14 @@ import Data.Text.Encoding (encodeUtf8)
 import qualified Data.Text.Lazy as LT
 import qualified Data.Text.Lazy.Encoding as LE
 import Data.Type.Equality
+import qualified Data.X509 as X
+import qualified Data.X509.CertificateStore as XS
+import qualified Data.X509.Validation as XV
+import qualified SMPClient
 import qualified Simplex.Messaging.Crypto as C
 import qualified Simplex.Messaging.Crypto.Lazy as LC
 import Simplex.Messaging.Crypto.SNTRUP761.Bindings
+import Simplex.Messaging.Transport.Client
 import Test.Hspec
 import Test.Hspec.QuickCheck (modifyMaxSuccess)
 import Test.QuickCheck
@@ -91,6 +96,8 @@ cryptoTests = do
     describe "Ed448" $ testEncoding C.SEd448
     describe "X25519" $ testEncoding C.SX25519
     describe "X448" $ testEncoding C.SX448
+  describe "X509 chains" $ do
+    it "should validate certificates" testValidateX509
   describe "sntrup761" $
     it "should enc/dec key" testSNTRUP761
 
@@ -223,6 +230,39 @@ testEncoding alg = it "should encode / decode key" . ioProperty $ do
     C.decodePubKey (C.encodePubKey k) == Right k
       && C.decodePrivKey (C.encodePrivKey pk) == Right pk
 
+testValidateX509 :: IO ()
+testValidateX509 = do
+  let checkChain = validateCertificateChain SMPClient.testKeyHash "localhost" "5223" . X.CertificateChain
+  checkChain [] `shouldReturn` [XV.EmptyChain]
+
+  caCreds <- XS.readCertificates "tests/fixtures/ca.crt"
+  caCreds `shouldNotBe` []
+  let ca = head caCreds
+
+  serverCreds <- XS.readCertificates "tests/fixtures/server.crt"
+  serverCreds `shouldNotBe` []
+  let server = head serverCreds
+  checkChain [server, ca] `shouldReturn` []
+
+  ca2Creds <- XS.readCertificates "tests/fixtures/ca2.crt"
+  ca2Creds `shouldNotBe` []
+  let ca2 = head ca2Creds
+
+  -- signed by another CA
+  server2Creds <- XS.readCertificates "tests/fixtures/server2.crt"
+  server2Creds `shouldNotBe` []
+  let server2 = head server2Creds
+  checkChain [server2, ca2] `shouldReturn` [XV.UnknownCA]
+
+  -- messed up key rotation or other configuration problems
+  checkChain [server2, ca] `shouldReturn` [XV.InvalidSignature XV.SignatureInvalid]
+
+  -- self-signed, unrelated to CA
+  ssCreds <- XS.readCertificates "tests/fixtures/ss.crt"
+  ssCreds `shouldNotBe` []
+  let ss = head ssCreds
+  checkChain [ss, ca] `shouldReturn` [XV.SelfSigned]
+
 testSNTRUP761 :: IO ()
 testSNTRUP761 = do
   drg <- C.newRandom

tests/CoreTests/ProtocolErrorTests.hs

@@ -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

tests/NtfClient.hs

@@ -70,13 +70,11 @@ testKeyHash = "LcJUMfVhwD8yxjAiSaDzzGF3-kLG4Uh0Fl_ZIjrRwjI="
 ntfTestStoreLogFile :: FilePath
 ntfTestStoreLogFile = "tests/tmp/ntf-server-store.log"
 
-testNtfClient :: Transport c => (THandleNTF c -> IO a) -> IO a
+testNtfClient :: Transport c => (THandleNTF c 'TClient -> IO a) -> IO a
 testNtfClient client = do
   Right host <- pure $ chooseTransportHost defaultNetworkConfig testHost
-  runTransportClient defaultTransportClientConfig Nothing host ntfTestPort (Just testKeyHash) $ \h -> do
-    g <- C.newRandom
-    ks <- atomically $ C.generateKeyPair g
-    runExceptT (ntfClientHandshake h ks testKeyHash supportedClientNTFVRange) >>= \case
+  runTransportClient defaultTransportClientConfig Nothing host ntfTestPort (Just testKeyHash) $ \h ->
+    runExceptT (ntfClientHandshake h testKeyHash supportedClientNTFVRange) >>= \case
       Right th -> client th
       Left e -> error $ show e
 
@@ -139,7 +137,7 @@ withNtfServerOn t port' = withNtfServerThreadOn t port' . const
 withNtfServer :: ATransport -> IO a -> IO a
 withNtfServer t = withNtfServerOn t ntfTestPort
 
-runNtfTest :: forall c a. Transport c => (THandleNTF c -> IO a) -> IO a
+runNtfTest :: forall c a. Transport c => (THandleNTF c 'TClient -> IO a) -> IO a
 runNtfTest test = withNtfServer (transport @c) $ testNtfClient test
 
 ntfServerTest ::
@@ -150,7 +148,7 @@ ntfServerTest ::
   IO (Maybe TransmissionAuth, ByteString, ByteString, NtfResponse)
 ntfServerTest _ t = runNtfTest $ \h -> tPut' h t >> tGet' h
   where
-    tPut' :: THandleNTF c -> (Maybe TransmissionAuth, ByteString, ByteString, smp) -> IO ()
+    tPut' :: THandleNTF c 'TClient -> (Maybe TransmissionAuth, ByteString, ByteString, smp) -> IO ()
     tPut' h@THandle {params = THandleParams {sessionId, implySessId}} (sig, corrId, queueId, smp) = do
       let t' = if implySessId then smpEncode (corrId, queueId, smp) else smpEncode (sessionId, corrId, queueId, smp)
       [Right ()] <- tPut h [Right (sig, t')]
@@ -159,7 +157,7 @@ ntfServerTest _ t = runNtfTest $ \h -> tPut' h t >> tGet' h
       [(Nothing, _, (CorrId corrId, qId, Right cmd))] <- tGet h
       pure (Nothing, corrId, qId, cmd)
 
-ntfTest :: Transport c => TProxy c -> (THandleNTF c -> IO ()) -> Expectation
+ntfTest :: Transport c => TProxy c -> (THandleNTF c 'TClient -> IO ()) -> Expectation
 ntfTest _ test' = runNtfTest test' `shouldReturn` ()
 
 data APNSMockRequest = APNSMockRequest

tests/NtfServerTests.hs

@@ -6,8 +6,8 @@
 {-# LANGUAGE PatternSynonyms #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE StandaloneDeriving #-}
-{-# OPTIONS_GHC -fno-warn-incomplete-uni-patterns #-}
 {-# OPTIONS_GHC -Wno-orphans #-}
+{-# OPTIONS_GHC -fno-warn-incomplete-uni-patterns #-}
 
 module NtfServerTests where
 
@@ -15,6 +15,7 @@ import Control.Concurrent (threadDelay)
 import qualified Data.Aeson as J
 import qualified Data.Aeson.Types as JT
 import Data.Bifunctor (first)
+import qualified Data.ByteString.Base64.URL as U
 import Data.ByteString.Char8 (ByteString)
 import Data.Text.Encoding (encodeUtf8)
 import NtfClient
@@ -34,7 +35,6 @@ import ServerTests
 import qualified Simplex.Messaging.Agent.Protocol as AP
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding
-import qualified Simplex.Messaging.Encoding.Base64.URL as U
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Notifications.Protocol
 import Simplex.Messaging.Notifications.Server.Push.APNS
@@ -72,13 +72,13 @@ pattern RespNtf corrId queueId command <- (_, _, (corrId, queueId, Right command
 
 deriving instance Eq NtfResponse
 
-sendRecvNtf :: forall c e. (Transport c, NtfEntityI e) => THandleNTF c -> (Maybe TransmissionAuth, ByteString, ByteString, NtfCommand e) -> IO (SignedTransmission ErrorType NtfResponse)
+sendRecvNtf :: forall c e. (Transport c, NtfEntityI e) => THandleNTF c 'TClient -> (Maybe TransmissionAuth, ByteString, ByteString, NtfCommand e) -> IO (SignedTransmission ErrorType NtfResponse)
 sendRecvNtf h@THandle {params} (sgn, corrId, qId, cmd) = do
   let TransmissionForAuth {tToSend} = encodeTransmissionForAuth params (CorrId corrId, qId, cmd)
   Right () <- tPut1 h (sgn, tToSend)
   tGet1 h
 
-signSendRecvNtf :: forall c e. (Transport c, NtfEntityI e) => THandleNTF c -> C.APrivateAuthKey -> (ByteString, ByteString, NtfCommand e) -> IO (SignedTransmission ErrorType NtfResponse)
+signSendRecvNtf :: forall c e. (Transport c, NtfEntityI e) => THandleNTF c 'TClient -> C.APrivateAuthKey -> (ByteString, ByteString, NtfCommand e) -> IO (SignedTransmission ErrorType NtfResponse)
 signSendRecvNtf h@THandle {params} (C.APrivateAuthKey a pk) (corrId, qId, cmd) = do
   let TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth params (CorrId corrId, qId, cmd)
   Right () <- tPut1 h (authorize tForAuth, tToSend)

tests/SMPClient.hs

@@ -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
@@ -67,16 +68,18 @@ xit'' d t = do
   ci <- runIO $ lookupEnv "CI"
   (if ci == Just "true" then skip "skipped on CI" . it d else it d) t
 
-testSMPClient :: Transport c => (THandleSMP c -> IO a) -> IO a
+testSMPClient :: Transport c => (THandleSMP c 'TClient -> IO a) -> IO a
 testSMPClient = testSMPClientVR supportedClientSMPRelayVRange
 
-testSMPClientVR :: Transport c => VersionRangeSMP -> (THandleSMP c -> IO a) -> IO a
+testSMPClientVR :: Transport c => VersionRangeSMP -> (THandleSMP c 'TClient -> IO a) -> IO a
 testSMPClientVR vr client = do
   Right useHost <- pure $ chooseTransportHost defaultNetworkConfig testHost
-  runTransportClient defaultTransportClientConfig Nothing useHost testPort (Just testKeyHash) $ \h -> do
-    g <- C.newRandom
-    ks <- atomically $ C.generateKeyPair g
-    runExceptT (smpClientHandshake h ks testKeyHash vr) >>= \case
+  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
 
@@ -107,12 +110,22 @@ cfg =
       certificateFile = "tests/fixtures/server.crt",
       smpServerVRange = supportedServerSMPRelayVRange,
       transportConfig = defaultTransportServerConfig,
-      controlPort = Nothing
+      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}
 
@@ -123,7 +136,7 @@ withSmpServerConfigOn :: HasCallStack => ATransport -> ServerConfig -> ServiceNa
 withSmpServerConfigOn t cfg' port' =
   serverBracket
     (\started -> runSMPServerBlocking started cfg' {transports = [(port', t)]})
-    (pure ())
+    (threadDelay 10000)
 
 withSmpServerThreadOn :: HasCallStack => ATransport -> ServiceName -> (HasCallStack => ThreadId -> IO a) -> IO a
 withSmpServerThreadOn t = withSmpServerConfigOn t cfg
@@ -150,16 +163,16 @@ withSmpServer t = withSmpServerOn t testPort
 withSmpServerV7 :: HasCallStack => ATransport -> IO a -> IO a
 withSmpServerV7 t = withSmpServerConfigOn t cfgV7 testPort . const
 
-runSmpTest :: forall c a. (HasCallStack, Transport c) => (HasCallStack => THandleSMP c -> IO a) -> IO a
+runSmpTest :: forall c a. (HasCallStack, Transport c) => (HasCallStack => THandleSMP c 'TClient -> IO a) -> IO a
 runSmpTest test = withSmpServer (transport @c) $ testSMPClient test
 
-runSmpTestN :: forall c a. (HasCallStack, Transport c) => Int -> (HasCallStack => [THandleSMP c] -> IO a) -> IO a
+runSmpTestN :: forall c a. (HasCallStack, Transport c) => Int -> (HasCallStack => [THandleSMP c 'TClient] -> IO a) -> IO a
 runSmpTestN = runSmpTestNCfg cfg supportedClientSMPRelayVRange
 
-runSmpTestNCfg :: forall c a. (HasCallStack, Transport c) => ServerConfig -> VersionRangeSMP -> Int -> (HasCallStack => [THandleSMP c] -> IO a) -> IO a
+runSmpTestNCfg :: forall c a. (HasCallStack, Transport c) => ServerConfig -> VersionRangeSMP -> Int -> (HasCallStack => [THandleSMP c 'TClient] -> IO a) -> IO a
 runSmpTestNCfg srvCfg clntVR nClients test = withSmpServerConfigOn (transport @c) srvCfg testPort $ \_ -> run nClients []
   where
-    run :: Int -> [THandleSMP c] -> IO a
+    run :: Int -> [THandleSMP c 'TClient] -> IO a
     run 0 hs = test hs
     run n hs = testSMPClientVR clntVR $ \h -> run (n - 1) (h : hs)
 
@@ -171,7 +184,7 @@ smpServerTest ::
   IO (Maybe TransmissionAuth, ByteString, ByteString, BrokerMsg)
 smpServerTest _ t = runSmpTest $ \h -> tPut' h t >> tGet' h
   where
-    tPut' :: THandleSMP c -> (Maybe TransmissionAuth, ByteString, ByteString, smp) -> IO ()
+    tPut' :: THandleSMP c 'TClient -> (Maybe TransmissionAuth, ByteString, ByteString, smp) -> IO ()
     tPut' h@THandle {params = THandleParams {sessionId, implySessId}} (sig, corrId, queueId, smp) = do
       let t' = if implySessId then smpEncode (corrId, queueId, smp) else smpEncode (sessionId, corrId, queueId, smp)
       [Right ()] <- tPut h [Right (sig, t')]
@@ -180,33 +193,33 @@ smpServerTest _ t = runSmpTest $ \h -> tPut' h t >> tGet' h
       [(Nothing, _, (CorrId corrId, qId, Right cmd))] <- tGet h
       pure (Nothing, corrId, qId, cmd)
 
-smpTest :: (HasCallStack, Transport c) => TProxy c -> (HasCallStack => THandleSMP c -> IO ()) -> Expectation
+smpTest :: (HasCallStack, Transport c) => TProxy c -> (HasCallStack => THandleSMP c 'TClient -> IO ()) -> Expectation
 smpTest _ test' = runSmpTest test' `shouldReturn` ()
 
-smpTestN :: (HasCallStack, Transport c) => Int -> (HasCallStack => [THandleSMP c] -> IO ()) -> Expectation
+smpTestN :: (HasCallStack, Transport c) => Int -> (HasCallStack => [THandleSMP c 'TClient] -> IO ()) -> Expectation
 smpTestN n test' = runSmpTestN n test' `shouldReturn` ()
 
-smpTest2 :: forall c. (HasCallStack, Transport c) => TProxy c -> (HasCallStack => THandleSMP c -> THandleSMP c -> IO ()) -> Expectation
+smpTest2 :: forall c. (HasCallStack, Transport c) => TProxy c -> (HasCallStack => THandleSMP c 'TClient -> THandleSMP c 'TClient -> IO ()) -> Expectation
 smpTest2 = smpTest2Cfg cfg supportedClientSMPRelayVRange
 
-smpTest2Cfg :: forall c. (HasCallStack, Transport c) => ServerConfig -> VersionRangeSMP -> TProxy c -> (HasCallStack => THandleSMP c -> THandleSMP c -> IO ()) -> Expectation
+smpTest2Cfg :: forall c. (HasCallStack, Transport c) => ServerConfig -> VersionRangeSMP -> TProxy c -> (HasCallStack => THandleSMP c 'TClient -> THandleSMP c 'TClient -> IO ()) -> Expectation
 smpTest2Cfg srvCfg clntVR _ test' = runSmpTestNCfg srvCfg clntVR 2 _test `shouldReturn` ()
   where
-    _test :: HasCallStack => [THandleSMP c] -> IO ()
+    _test :: HasCallStack => [THandleSMP c 'TClient] -> IO ()
     _test [h1, h2] = test' h1 h2
     _test _ = error "expected 2 handles"
 
-smpTest3 :: forall c. (HasCallStack, Transport c) => TProxy c -> (HasCallStack => THandleSMP c -> THandleSMP c -> THandleSMP c -> IO ()) -> Expectation
+smpTest3 :: forall c. (HasCallStack, Transport c) => TProxy c -> (HasCallStack => THandleSMP c 'TClient -> THandleSMP c 'TClient -> THandleSMP c 'TClient -> IO ()) -> Expectation
 smpTest3 _ test' = smpTestN 3 _test
   where
-    _test :: HasCallStack => [THandleSMP c] -> IO ()
+    _test :: HasCallStack => [THandleSMP c 'TClient] -> IO ()
     _test [h1, h2, h3] = test' h1 h2 h3
     _test _ = error "expected 3 handles"
 
-smpTest4 :: forall c. (HasCallStack, Transport c) => TProxy c -> (HasCallStack => THandleSMP c -> THandleSMP c -> THandleSMP c -> THandleSMP c -> IO ()) -> Expectation
+smpTest4 :: forall c. (HasCallStack, Transport c) => TProxy c -> (HasCallStack => THandleSMP c 'TClient -> THandleSMP c 'TClient -> THandleSMP c 'TClient -> THandleSMP c 'TClient -> IO ()) -> Expectation
 smpTest4 _ test' = smpTestN 4 _test
   where
-    _test :: HasCallStack => [THandleSMP c] -> IO ()
+    _test :: HasCallStack => [THandleSMP c 'TClient] -> IO ()
     _test [h1, h2, h3, h4] = test' h1 h2 h3 h4
     _test _ = error "expected 4 handles"
 

tests/SMPProxyTests.hs

@@ -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"

tests/ServerTests.hs

@@ -22,6 +22,7 @@ import Control.Exception (SomeException, try)
 import Control.Monad
 import Control.Monad.IO.Class
 import Data.Bifunctor (first)
+import Data.ByteString.Base64
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
 import qualified Data.Set as S
@@ -30,7 +31,6 @@ import GHC.Stack (withFrozenCallStack)
 import SMPClient
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Encoding
-import Simplex.Messaging.Encoding.Base64 (encode)
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Parsers (parseAll)
 import Simplex.Messaging.Protocol
@@ -78,13 +78,13 @@ pattern Ids rId sId srvDh <- IDS (QIK rId sId srvDh)
 pattern Msg :: MsgId -> MsgBody -> BrokerMsg
 pattern Msg msgId body <- MSG RcvMessage {msgId, msgBody = EncRcvMsgBody body}
 
-sendRecv :: forall c p. (Transport c, PartyI p) => THandleSMP c -> (Maybe TransmissionAuth, ByteString, ByteString, Command p) -> IO (SignedTransmission ErrorType BrokerMsg)
+sendRecv :: forall c p. (Transport c, PartyI p) => THandleSMP c 'TClient -> (Maybe TransmissionAuth, ByteString, ByteString, Command p) -> IO (SignedTransmission ErrorType BrokerMsg)
 sendRecv h@THandle {params} (sgn, corrId, qId, cmd) = do
   let TransmissionForAuth {tToSend} = encodeTransmissionForAuth params (CorrId corrId, qId, cmd)
   Right () <- tPut1 h (sgn, tToSend)
   tGet1 h
 
-signSendRecv :: forall c p. (Transport c, PartyI p) => THandleSMP c -> C.APrivateAuthKey -> (ByteString, ByteString, Command p) -> IO (SignedTransmission ErrorType BrokerMsg)
+signSendRecv :: forall c p. (Transport c, PartyI p) => THandleSMP c 'TClient -> C.APrivateAuthKey -> (ByteString, ByteString, Command p) -> IO (SignedTransmission ErrorType BrokerMsg)
 signSendRecv h@THandle {params} (C.APrivateAuthKey a pk) (corrId, qId, cmd) = do
   let TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth params (CorrId corrId, qId, cmd)
   Right () <- tPut1 h (authorize tForAuth, tToSend)
@@ -93,17 +93,17 @@ signSendRecv h@THandle {params} (C.APrivateAuthKey a pk) (corrId, qId, cmd) = do
     authorize t = case a of
       C.SEd25519 -> Just . TASignature . C.ASignature C.SEd25519 $ C.sign' pk t
       C.SEd448 -> Just . TASignature . C.ASignature C.SEd448 $ C.sign' pk t
-      C.SX25519 -> (\THandleAuth {peerPubKey} -> TAAuthenticator $ C.cbAuthenticate peerPubKey pk (C.cbNonce corrId) t) <$> thAuth params
+      C.SX25519 -> (\THAuthClient {serverPeerPubKey = k} -> TAAuthenticator $ C.cbAuthenticate k pk (C.cbNonce corrId) t) <$> thAuth params
 #if !MIN_VERSION_base(4,18,0)
       _sx448 -> undefined -- ghc8107 fails to the branch excluded by types
 #endif
 
-tPut1 :: Transport c => THandle v c -> SentRawTransmission -> IO (Either TransportError ())
+tPut1 :: Transport c => THandle v c 'TClient -> SentRawTransmission -> IO (Either TransportError ())
 tPut1 h t = do
   [r] <- tPut h [Right t]
   pure r
 
-tGet1 :: (ProtocolEncoding v err cmd, Transport c) => THandle v c -> IO (SignedTransmission err cmd)
+tGet1 :: (ProtocolEncoding v err cmd, Transport c) => THandle v c 'TClient -> IO (SignedTransmission err cmd)
 tGet1 h = do
   [r] <- liftIO $ tGet h
   pure r
@@ -555,12 +555,12 @@ testWithStoreLog at@(ATransport t) =
     logSize testStoreLogFile `shouldReturn` 1
     removeFile testStoreLogFile
   where
-    runTest :: Transport c => TProxy c -> (THandleSMP c -> IO ()) -> ThreadId -> Expectation
+    runTest :: Transport c => TProxy c -> (THandleSMP c 'TClient -> IO ()) -> ThreadId -> Expectation
     runTest _ test' server = do
       testSMPClient test' `shouldReturn` ()
       killThread server
 
-    runClient :: Transport c => TProxy c -> (THandleSMP c -> IO ()) -> Expectation
+    runClient :: Transport c => TProxy c -> (THandleSMP c 'TClient -> IO ()) -> Expectation
     runClient _ test' = testSMPClient test' `shouldReturn` ()
 
 logSize :: FilePath -> IO Int
@@ -653,12 +653,12 @@ testRestoreMessages at@(ATransport t) =
     removeFile testStoreMsgsFile
     removeFile testServerStatsBackupFile
   where
-    runTest :: Transport c => TProxy c -> (THandleSMP c -> IO ()) -> ThreadId -> Expectation
+    runTest :: Transport c => TProxy c -> (THandleSMP c 'TClient -> IO ()) -> ThreadId -> Expectation
     runTest _ test' server = do
       testSMPClient test' `shouldReturn` ()
       killThread server
 
-    runClient :: Transport c => TProxy c -> (THandleSMP c -> IO ()) -> Expectation
+    runClient :: Transport c => TProxy c -> (THandleSMP c 'TClient -> IO ()) -> Expectation
     runClient _ test' = testSMPClient test' `shouldReturn` ()
 
 checkStats :: ServerStatsData -> [RecipientId] -> Int -> Int -> Expectation
@@ -727,15 +727,15 @@ testRestoreExpireMessages at@(ATransport t) =
     Right ServerStatsData {_msgExpired} <- strDecode <$> B.readFile testServerStatsBackupFile
     _msgExpired `shouldBe` 2
   where
-    runTest :: Transport c => TProxy c -> (THandleSMP c -> IO ()) -> ThreadId -> Expectation
+    runTest :: Transport c => TProxy c -> (THandleSMP c 'TClient -> IO ()) -> ThreadId -> Expectation
     runTest _ test' server = do
       testSMPClient test' `shouldReturn` ()
       killThread server
 
-    runClient :: Transport c => TProxy c -> (THandleSMP c -> IO ()) -> Expectation
+    runClient :: Transport c => TProxy c -> (THandleSMP c 'TClient -> IO ()) -> Expectation
     runClient _ test' = testSMPClient test' `shouldReturn` ()
 
-createAndSecureQueue :: Transport c => THandleSMP c -> SndPublicAuthKey -> IO (SenderId, RecipientId, RcvPrivateAuthKey, RcvDhSecret)
+createAndSecureQueue :: Transport c => THandleSMP c 'TClient -> SndPublicAuthKey -> IO (SenderId, RecipientId, RcvPrivateAuthKey, RcvDhSecret)
 createAndSecureQueue h sPub = do
   g <- C.newRandom
   (rPub, rKey) <- atomically $ C.generateAuthKeyPair C.SEd448 g
@@ -759,8 +759,8 @@ testTiming (ATransport t) =
     timingTests :: [(C.AuthAlg, C.AuthAlg, Int)]
     timingTests =
       [ (C.AuthAlg C.SEd25519, C.AuthAlg C.SEd25519, 200), -- correct key type
-        -- (C.AuthAlg C.SEd25519, C.AuthAlg C.SEd448, 150),
-        -- (C.AuthAlg C.SEd25519, C.AuthAlg C.SX25519, 200),
+      -- (C.AuthAlg C.SEd25519, C.AuthAlg C.SEd448, 150),
+      -- (C.AuthAlg C.SEd25519, C.AuthAlg C.SX25519, 200),
         (C.AuthAlg C.SEd448, C.AuthAlg C.SEd25519, 200),
         (C.AuthAlg C.SEd448, C.AuthAlg C.SEd448, 150), -- correct key type
         (C.AuthAlg C.SEd448, C.AuthAlg C.SX25519, 200),
@@ -769,8 +769,8 @@ testTiming (ATransport t) =
         (C.AuthAlg C.SX25519, C.AuthAlg C.SX25519, 200) -- correct key type
       ]
     timeRepeat n = fmap fst . timeItT . forM_ (replicate n ()) . const
-    similarTime t1 t2 = abs (t2 / t1 - 1) < 0.15 -- normally the difference between "no queue" and "wrong key" is less than 5%
-    testSameTiming :: forall c. Transport c => THandleSMP c -> THandleSMP c -> (C.AuthAlg, C.AuthAlg, Int) -> Expectation
+    similarTime t1 t2 = abs (t2 / t1 - 1) < 0.2 -- normally the difference between "no queue" and "wrong key" is less than 5%
+    testSameTiming :: forall c. Transport c => THandleSMP c 'TClient -> THandleSMP c 'TClient -> (C.AuthAlg, C.AuthAlg, Int) -> Expectation
     testSameTiming rh sh (C.AuthAlg goodKeyAlg, C.AuthAlg badKeyAlg, n) = do
       g <- C.newRandom
       (rPub, rKey) <- atomically $ C.generateAuthKeyPair goodKeyAlg g
@@ -791,10 +791,11 @@ testTiming (ATransport t) =
 
       runTimingTest sh badKey sId $ _SEND "hello"
       where
-        runTimingTest :: PartyI p => THandleSMP c -> C.APrivateAuthKey -> ByteString -> Command p -> IO ()
+        runTimingTest :: PartyI p => THandleSMP c 'TClient -> C.APrivateAuthKey -> ByteString -> Command p -> IO ()
         runTimingTest h badKey qId cmd = do
           threadDelay 100000
-          _ <- timeRepeat n $ do -- "warm up" the server
+          _ <- timeRepeat n $ do
+            -- "warm up" the server
             Resp "dabc" _ (ERR AUTH) <- signSendRecv h badKey ("dabc", "1234", cmd)
             return ()
           threadDelay 100000
@@ -930,8 +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)

tests/Test.hs

@@ -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

tests/XFTPAgent.hs

@@ -8,7 +8,7 @@
 
 module XFTPAgent where
 
-import AgentTests.FunctionalAPITests (get, getSMPAgentClient', rfGet, runRight, runRight_, sfGet)
+import AgentTests.FunctionalAPITests (get, rfGet, runRight, runRight_, sfGet, withAgent)
 
 import Control.Logger.Simple
 import Control.Monad
@@ -20,12 +20,14 @@ import Data.Int (Int64)
 import Data.List (find, isSuffixOf)
 import Data.Maybe (fromJust)
 import SMPAgentClient (agentCfg, initAgentServers, testDB, testDB2, testDB3)
-import Simplex.FileTransfer.Description (FileChunk (..), FileDescription (..), FileDescriptionURI (..), ValidFileDescription, fileDescriptionURI, mb, qrSizeLimit, pattern ValidFileDescription)
+import Simplex.FileTransfer.Client (XFTPClientConfig (..))
+import Simplex.FileTransfer.Description (FileChunk (..), FileDescription (..), FileDescriptionURI (..), ValidFileDescription, fileDescriptionURI, kb, mb, qrSizeLimit, pattern ValidFileDescription)
 import Simplex.FileTransfer.Protocol (FileParty (..))
 import Simplex.FileTransfer.Server.Env (XFTPServerConfig (..))
 import Simplex.FileTransfer.Transport (XFTPErrorType (AUTH))
-import Simplex.Messaging.Agent (AgentClient, disposeAgentClient, testProtocolServer, xftpDeleteRcvFile, xftpDeleteSndFileInternal, xftpDeleteSndFileRemote, xftpReceiveFile, xftpSendDescription, xftpSendFile, xftpStartWorkers)
+import Simplex.Messaging.Agent (AgentClient, testProtocolServer, xftpDeleteRcvFile, xftpDeleteSndFileInternal, xftpDeleteSndFileRemote, xftpReceiveFile, xftpSendDescription, xftpSendFile, xftpStartWorkers)
 import Simplex.Messaging.Agent.Client (ProtocolTestFailure (..), ProtocolTestStep (..))
+import Simplex.Messaging.Agent.Env.SQLite (AgentConfig, xftpCfg)
 import Simplex.Messaging.Agent.Protocol (ACommand (..), AgentErrorType (..), BrokerErrorType (..), RcvFileId, SndFileId, noAuthSrv)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Crypto.File (CryptoFile (..), CryptoFileArgs)
@@ -48,6 +50,7 @@ xftpAgentTests = around_ testBracket . describe "agent XFTP API" $ do
   it "should send and receive with encrypted local files" testXFTPAgentSendReceiveEncrypted
   it "should send and receive large file with a redirect" testXFTPAgentSendReceiveRedirect
   it "should send and receive small file without a redirect" testXFTPAgentSendReceiveNoRedirect
+  describe "sending and receiving with version negotiation" testXFTPAgentSendReceiveMatrix
   it "should resume receiving file after restart" testXFTPAgentReceiveRestore
   it "should cleanup rcv tmp path after permanent error" testXFTPAgentReceiveCleanup
   it "should resume sending file after restart" testXFTPAgentSendRestore
@@ -90,7 +93,7 @@ sfProgress c expected = loop 0
 -- checks that progress increases till it reaches total
 checkProgress :: (HasCallStack, MonadIO m) => (Int64, Int64) -> (Int64, Int64) -> (Int64 -> m ()) -> m ()
 checkProgress (prev, expected) (progress, total) loop
-  | total /= expected = error "total /= expected"
+  | total /= expected = liftIO (print total) >> error "total /= expected"
   | progress <= prev = error "progress <= prev"
   | progress > total = error "progress > total"
   | progress < total = loop progress
@@ -100,8 +103,7 @@ testXFTPAgentSendReceive :: HasCallStack => IO ()
 testXFTPAgentSendReceive = withXFTPServer $ do
   filePath <- createRandomFile
   -- send file, delete snd file internally
-  sndr <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-  (rfd1, rfd2) <- runRight $ do
+  (rfd1, rfd2) <- withAgent 1 agentCfg initAgentServers testDB $ \sndr -> runRight $ do
     (sfId, _, rfd1, rfd2) <- testSend sndr filePath
     liftIO $ xftpDeleteSndFileInternal sndr sfId
     pure (rfd1, rfd2)
@@ -109,11 +111,10 @@ testXFTPAgentSendReceive = withXFTPServer $ do
   testReceiveDelete 2 rfd1 filePath
   testReceiveDelete 3 rfd2 filePath
   where
-    testReceiveDelete clientId rfd originalFilePath = do
-      rcp <- getSMPAgentClient' clientId agentCfg initAgentServers testDB2
-      rfId <- runRight $ testReceive rcp rfd originalFilePath
-      xftpDeleteRcvFile rcp rfId
-      disposeAgentClient rcp
+    testReceiveDelete clientId rfd originalFilePath =
+      withAgent clientId agentCfg initAgentServers testDB2 $ \rcp -> do
+        rfId <- runRight $ testReceive rcp rfd originalFilePath
+        xftpDeleteRcvFile rcp rfId
 
 testXFTPAgentSendReceiveEncrypted :: HasCallStack => IO ()
 testXFTPAgentSendReceiveEncrypted = withXFTPServer $ do
@@ -122,8 +123,7 @@ testXFTPAgentSendReceiveEncrypted = withXFTPServer $ do
   s <- LB.readFile filePath
   file <- atomically $ CryptoFile (senderFiles </> "encrypted_testfile") . Just <$> CF.randomArgs g
   runRight_ $ CF.writeFile file s
-  sndr <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-  (rfd1, rfd2) <- runRight $ do
+  (rfd1, rfd2) <- withAgent 1 agentCfg initAgentServers testDB $ \sndr -> runRight $ do
     (sfId, _, rfd1, rfd2) <- testSendCF sndr file
     liftIO $ xftpDeleteSndFileInternal sndr sfId
     pure (rfd1, rfd2)
@@ -131,12 +131,11 @@ testXFTPAgentSendReceiveEncrypted = withXFTPServer $ do
   testReceiveDelete 2 rfd1 filePath g
   testReceiveDelete 3 rfd2 filePath g
   where
-    testReceiveDelete clientId rfd originalFilePath g = do
-      rcp <- getSMPAgentClient' clientId agentCfg initAgentServers testDB2
-      cfArgs <- atomically $ Just <$> CF.randomArgs g
-      rfId <- runRight $ testReceiveCF rcp rfd cfArgs originalFilePath
-      xftpDeleteRcvFile rcp rfId
-      disposeAgentClient rcp
+    testReceiveDelete clientId rfd originalFilePath g =
+      withAgent clientId agentCfg initAgentServers testDB2 $ \rcp -> do
+        cfArgs <- atomically $ Just <$> CF.randomArgs g
+        rfId <- runRight $ testReceiveCF rcp rfd cfArgs originalFilePath
+        xftpDeleteRcvFile rcp rfId
 
 testXFTPAgentSendReceiveRedirect :: HasCallStack => IO ()
 testXFTPAgentSendReceiveRedirect = withXFTPServer $ do
@@ -144,102 +143,126 @@ testXFTPAgentSendReceiveRedirect = withXFTPServer $ do
   filePathIn <- createRandomFile
   let fileSize = mb 17
       totalSize = fileSize + mb 1
-  sndr <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-  directFileId <- runRight $ xftpSendFile sndr 1 (CryptoFile filePathIn Nothing) 1
-  sfGet sndr `shouldReturn` ("", directFileId, SFPROG 4194304 totalSize)
-  sfGet sndr `shouldReturn` ("", directFileId, SFPROG 8388608 totalSize)
-  sfGet sndr `shouldReturn` ("", directFileId, SFPROG 12582912 totalSize)
-  sfGet sndr `shouldReturn` ("", directFileId, SFPROG 16777216 totalSize)
-  sfGet sndr `shouldReturn` ("", directFileId, SFPROG 17825792 totalSize)
-  sfGet sndr `shouldReturn` ("", directFileId, SFPROG totalSize totalSize)
-  vfdDirect <-
-    sfGet sndr >>= \case
-      (_, _, SFDONE _snd (vfd : _)) -> pure vfd
-      r -> error $ "Expected SFDONE, got " <> show r
+  withAgent 1 agentCfg initAgentServers testDB $ \sndr -> do
+    directFileId <- runRight $ xftpSendFile sndr 1 (CryptoFile filePathIn Nothing) 1
+    sfGet sndr `shouldReturn` ("", directFileId, SFPROG 4194304 totalSize)
+    sfGet sndr `shouldReturn` ("", directFileId, SFPROG 8388608 totalSize)
+    sfGet sndr `shouldReturn` ("", directFileId, SFPROG 12582912 totalSize)
+    sfGet sndr `shouldReturn` ("", directFileId, SFPROG 16777216 totalSize)
+    sfGet sndr `shouldReturn` ("", directFileId, SFPROG 17825792 totalSize)
+    sfGet sndr `shouldReturn` ("", directFileId, SFPROG totalSize totalSize)
+    vfdDirect <-
+      sfGet sndr >>= \case
+        (_, _, SFDONE _snd (vfd : _)) -> pure vfd
+        r -> error $ "Expected SFDONE, got " <> show r
 
-  testNoRedundancy vfdDirect
+    testNoRedundancy vfdDirect
 
-  redirectFileId <- runRight $ xftpSendDescription sndr 1 vfdDirect 1
-  logInfo $ "File sent, sending redirect: " <> tshow redirectFileId
-  sfGet sndr `shouldReturn` ("", redirectFileId, SFPROG 65536 65536)
-  vfdRedirect@(ValidFileDescription fdRedirect) <-
-    sfGet sndr >>= \case
-      (_, _, SFDONE _snd (vfd : _)) -> pure vfd
-      r -> error $ "Expected SFDONE, got " <> show r
+    redirectFileId <- runRight $ xftpSendDescription sndr 1 vfdDirect 1
+    logInfo $ "File sent, sending redirect: " <> tshow redirectFileId
+    sfGet sndr `shouldReturn` ("", redirectFileId, SFPROG 65536 65536)
+    vfdRedirect@(ValidFileDescription fdRedirect) <-
+      sfGet sndr >>= \case
+        (_, _, SFDONE _snd (vfd : _)) -> pure vfd
+        r -> error $ "Expected SFDONE, got " <> show r
 
-  testNoRedundancy vfdRedirect
+    testNoRedundancy vfdRedirect
 
-  case fdRedirect of
-    FileDescription {redirect = Just _} -> pure ()
-    _ -> error "missing RedirectFileInfo"
-  let uri = strEncode $ fileDescriptionURI vfdRedirect
-  case strDecode uri of
-    Left err -> fail err
-    Right ok -> ok `shouldBe` fileDescriptionURI vfdRedirect
-  disposeAgentClient sndr
-  --- recipient
-  rcp <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
-  FileDescriptionURI {description} <- either fail pure $ strDecode uri
+    case fdRedirect of
+      FileDescription {redirect = Just _} -> pure ()
+      _ -> error "missing RedirectFileInfo"
+    let uri = strEncode $ fileDescriptionURI vfdRedirect
+    case strDecode uri of
+      Left err -> fail err
+      Right ok -> ok `shouldBe` fileDescriptionURI vfdRedirect
+    --- recipient
+    withAgent 2 agentCfg initAgentServers testDB2 $ \rcp -> do
+      FileDescriptionURI {description} <- either fail pure $ strDecode uri
 
-  rcvFileId <- runRight $ xftpReceiveFile rcp 1 description Nothing
-  rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 65536 totalSize) -- extra RFPROG before switching to real file
-  rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 4194304 totalSize)
-  rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 8388608 totalSize)
-  rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 12582912 totalSize)
-  rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 16777216 totalSize)
-  rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 17825792 totalSize)
-  rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG totalSize totalSize)
-  out <-
-    rfGet rcp >>= \case
-      (_, _, RFDONE out) -> pure out
-      r -> error $ "Expected RFDONE, got " <> show r
-  disposeAgentClient rcp
+      rcvFileId <- runRight $ xftpReceiveFile rcp 1 description Nothing
+      rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 65536 totalSize) -- extra RFPROG before switching to real file
+      rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 4194304 totalSize)
+      rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 8388608 totalSize)
+      rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 12582912 totalSize)
+      rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 16777216 totalSize)
+      rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 17825792 totalSize)
+      rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG totalSize totalSize)
+      out <-
+        rfGet rcp >>= \case
+          (_, _, RFDONE out) -> pure out
+          r -> error $ "Expected RFDONE, got " <> show r
 
-  inBytes <- B.readFile filePathIn
-  B.readFile out `shouldReturn` inBytes
+      inBytes <- B.readFile filePathIn
+      B.readFile out `shouldReturn` inBytes
 
 testXFTPAgentSendReceiveNoRedirect :: HasCallStack => IO ()
 testXFTPAgentSendReceiveNoRedirect = withXFTPServer $ do
   --- sender
   let fileSize = mb 5
   filePathIn <- createRandomFile_ fileSize "testfile"
-  sndr <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-  directFileId <- runRight $ xftpSendFile sndr 1 (CryptoFile filePathIn Nothing) 1
-  let totalSize = fileSize + mb 1
-  sfGet sndr `shouldReturn` ("", directFileId, SFPROG 4194304 totalSize)
-  sfGet sndr `shouldReturn` ("", directFileId, SFPROG 5242880 totalSize)
-  sfGet sndr `shouldReturn` ("", directFileId, SFPROG totalSize totalSize)
-  vfdDirect <-
-    sfGet sndr >>= \case
-      (_, _, SFDONE _snd (vfd : _)) -> pure vfd
-      r -> error $ "Expected SFDONE, got " <> show r
+  withAgent 1 agentCfg initAgentServers testDB $ \sndr -> do
+    directFileId <- runRight $ xftpSendFile sndr 1 (CryptoFile filePathIn Nothing) 1
+    let totalSize = fileSize + mb 1
+    sfGet sndr `shouldReturn` ("", directFileId, SFPROG 4194304 totalSize)
+    sfGet sndr `shouldReturn` ("", directFileId, SFPROG 5242880 totalSize)
+    sfGet sndr `shouldReturn` ("", directFileId, SFPROG totalSize totalSize)
+    vfdDirect <-
+      sfGet sndr >>= \case
+        (_, _, SFDONE _snd (vfd : _)) -> pure vfd
+        r -> error $ "Expected SFDONE, got " <> show r
 
-  testNoRedundancy vfdDirect
+    testNoRedundancy vfdDirect
 
-  let uri = strEncode $ fileDescriptionURI vfdDirect
-  B.length uri `shouldSatisfy` (< qrSizeLimit)
-  case strDecode uri of
-    Left err -> fail err
-    Right ok -> ok `shouldBe` fileDescriptionURI vfdDirect
-  disposeAgentClient sndr
-  --- recipient
-  rcp <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
-  FileDescriptionURI {description} <- either fail pure $ strDecode uri
-  let ValidFileDescription FileDescription {redirect} = description
-  redirect `shouldBe` Nothing
-  rcvFileId <- runRight $ xftpReceiveFile rcp 1 description Nothing
-  -- NO extra "RFPROG 65k 65k" before switching to real file
-  rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 4194304 totalSize)
-  rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 5242880 totalSize)
-  rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG totalSize totalSize)
-  out <-
-    rfGet rcp >>= \case
-      (_, _, RFDONE out) -> pure out
-      r -> error $ "Expected RFDONE, got " <> show r
-  disposeAgentClient rcp
+    let uri = strEncode $ fileDescriptionURI vfdDirect
+    B.length uri `shouldSatisfy` (< qrSizeLimit)
+    case strDecode uri of
+      Left err -> fail err
+      Right ok -> ok `shouldBe` fileDescriptionURI vfdDirect
+    --- recipient
+    withAgent 2 agentCfg initAgentServers testDB2 $ \rcp -> do
+      FileDescriptionURI {description} <- either fail pure $ strDecode uri
+      let ValidFileDescription FileDescription {redirect} = description
+      redirect `shouldBe` Nothing
+      rcvFileId <- runRight $ xftpReceiveFile rcp 1 description Nothing
+      -- NO extra "RFPROG 65k 65k" before switching to real file
+      rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 4194304 totalSize)
+      rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG 5242880 totalSize)
+      rfGet rcp `shouldReturn` ("", rcvFileId, RFPROG totalSize totalSize)
+      out <-
+        rfGet rcp >>= \case
+          (_, _, RFDONE out) -> pure out
+          r -> error $ "Expected RFDONE, got " <> show r
 
-  inBytes <- B.readFile filePathIn
-  B.readFile out `shouldReturn` inBytes
+      inBytes <- B.readFile filePathIn
+      B.readFile out `shouldReturn` inBytes
+
+testXFTPAgentSendReceiveMatrix :: Spec
+testXFTPAgentSendReceiveMatrix = do
+  describe "old server" $ do
+    it "new clients" $ run oldServer newClient newClient
+    it "new sender, old recipient" $ run oldServer newClient newClient
+    it "old sender, new recipient" $ run oldServer oldClient newClient
+    it "old clients" $ run oldServer oldClient oldClient
+  describe "new server" $ do
+    it "new clients" $ run newServer newClient newClient
+    it "new sender, old recipient" $ run newServer newClient newClient
+    it "old sender, new recipient" $ run newServer oldClient newClient
+    it "old clients" $ run newServer oldClient oldClient
+  where
+    oldClient = agentCfg {xftpCfg = (xftpCfg agentCfg) {clientALPN = Nothing}}
+    newClient = agentCfg
+    oldServer = testXFTPServerConfig_ Nothing
+    newServer = testXFTPServerConfig
+    run :: HasCallStack => XFTPServerConfig -> AgentConfig -> AgentConfig -> IO ()
+    run server sender receiver =
+      withXFTPServerCfg server $ \_t -> do
+        filePath <- createRandomFile_ (kb 319 :: Integer) "testfile"
+        rfd <- withAgent 1 sender initAgentServers testDB $ \sndr -> do
+          (sfId, _, rfd1, _) <- runRight $ testSendCF' sndr (CF.plain filePath) (kb 320)
+          rfd1 <$ xftpDeleteSndFileInternal sndr sfId
+        withAgent 2 receiver initAgentServers testDB2 $ \rcp -> do
+          rfId <- runRight $ testReceiveCF' rcp rfd Nothing filePath (kb 320)
+          xftpDeleteRcvFile rcp rfId
 
 createRandomFile :: HasCallStack => IO FilePath
 createRandomFile = createRandomFile' "testfile"
@@ -258,10 +281,13 @@ testSend :: HasCallStack => AgentClient -> FilePath -> ExceptT AgentErrorType IO
 testSend sndr = testSendCF sndr . CF.plain
 
 testSendCF :: HasCallStack => AgentClient -> CryptoFile -> ExceptT AgentErrorType IO (SndFileId, ValidFileDescription 'FSender, ValidFileDescription 'FRecipient, ValidFileDescription 'FRecipient)
-testSendCF sndr file = do
+testSendCF sndr file = testSendCF' sndr file $ mb 18
+
+testSendCF' :: HasCallStack => AgentClient -> CryptoFile -> Int64 -> ExceptT AgentErrorType IO (SndFileId, ValidFileDescription 'FSender, ValidFileDescription 'FRecipient, ValidFileDescription 'FRecipient)
+testSendCF' sndr file size = do
   xftpStartWorkers sndr (Just senderFiles)
   sfId <- xftpSendFile sndr 1 file 2
-  sfProgress sndr $ mb 18
+  sfProgress sndr size
   ("", sfId', SFDONE sndDescr [rfd1, rfd2]) <- sfGet sndr
   liftIO $ testNoRedundancy rfd1
   liftIO $ testNoRedundancy rfd2
@@ -278,15 +304,15 @@ testReceive rcp rfd = testReceiveCF rcp rfd Nothing
 testReceiveCF :: HasCallStack => AgentClient -> ValidFileDescription 'FRecipient -> Maybe CryptoFileArgs -> FilePath -> ExceptT AgentErrorType IO RcvFileId
 testReceiveCF rcp rfd cfArgs originalFilePath = do
   xftpStartWorkers rcp (Just recipientFiles)
-  testReceiveCF' rcp rfd cfArgs originalFilePath
+  testReceiveCF' rcp rfd cfArgs originalFilePath $ mb 18
 
 testReceive' :: HasCallStack => AgentClient -> ValidFileDescription 'FRecipient -> FilePath -> ExceptT AgentErrorType IO RcvFileId
-testReceive' rcp rfd = testReceiveCF' rcp rfd Nothing
+testReceive' rcp rfd originalFilePath = testReceiveCF' rcp rfd Nothing originalFilePath $ mb 18
 
-testReceiveCF' :: HasCallStack => AgentClient -> ValidFileDescription 'FRecipient -> Maybe CryptoFileArgs -> FilePath -> ExceptT AgentErrorType IO RcvFileId
-testReceiveCF' rcp rfd cfArgs originalFilePath = do
+testReceiveCF' :: HasCallStack => AgentClient -> ValidFileDescription 'FRecipient -> Maybe CryptoFileArgs -> FilePath -> Int64 -> ExceptT AgentErrorType IO RcvFileId
+testReceiveCF' rcp rfd cfArgs originalFilePath size = do
   rfId <- xftpReceiveFile rcp 1 rfd cfArgs
-  rfProgress rcp $ mb 18
+  rfProgress rcp size
   ("", rfId', RFDONE path) <- rfGet rcp
   liftIO $ do
     rfId' `shouldBe` rfId
@@ -298,52 +324,48 @@ logCfgNoLogs :: LogConfig
 logCfgNoLogs = LogConfig {lc_file = Nothing, lc_stderr = False}
 
 testXFTPAgentReceiveRestore :: HasCallStack => IO ()
-testXFTPAgentReceiveRestore = withGlobalLogging logCfgNoLogs $ do
+testXFTPAgentReceiveRestore = do
   filePath <- createRandomFile
 
-  rfd <- withXFTPServerStoreLogOn $ \_ -> do
+  rfd <- withXFTPServerStoreLogOn $ \_ ->
     -- send file
-    sndr <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-    runRight $ do
+    withAgent 1 agentCfg initAgentServers testDB $ \sndr -> runRight $ do
       (_, _, rfd, _) <- testSend sndr filePath
       pure rfd
 
   -- receive file - should not succeed with server down
-  rcp <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
-  rfId <- runRight $ do
+  rfId <- withAgent 2 agentCfg initAgentServers testDB2 $ \rcp -> runRight $ do
     xftpStartWorkers rcp (Just recipientFiles)
     rfId <- xftpReceiveFile rcp 1 rfd Nothing
     liftIO $ timeout 300000 (get rcp) `shouldReturn` Nothing -- wait for worker attempt
     pure rfId
-  disposeAgentClient rcp
 
   [prefixDir] <- listDirectory recipientFiles
   let tmpPath = recipientFiles </> prefixDir </> "xftp.encrypted"
   doesDirectoryExist tmpPath `shouldReturn` True
 
-  withXFTPServerStoreLogOn $ \_ -> do
+  withXFTPServerStoreLogOn $ \_ ->
     -- receive file - should start downloading with server up
-    rcp' <- getSMPAgentClient' 3 agentCfg initAgentServers testDB2
-    runRight_ $ xftpStartWorkers rcp' (Just recipientFiles)
-    ("", rfId', RFPROG _ _) <- rfGet rcp'
-    liftIO $ rfId' `shouldBe` rfId
-    disposeAgentClient rcp'
-
+    withAgent 3 agentCfg initAgentServers testDB2 $ \rcp' -> do
+      runRight_ $ xftpStartWorkers rcp' (Just recipientFiles)
+      ("", rfId', RFPROG _ _) <- rfGet rcp'
+      liftIO $ rfId' `shouldBe` rfId
   threadDelay 100000
 
-  withXFTPServerStoreLogOn $ \_ -> do
+  withXFTPServerStoreLogOn $ \_ ->
     -- receive file - should continue downloading with server up
-    rcp' <- getSMPAgentClient' 4 agentCfg initAgentServers testDB2
-    runRight_ $ xftpStartWorkers rcp' (Just recipientFiles)
-    rfProgress rcp' $ mb 18
-    ("", rfId', RFDONE path) <- rfGet rcp'
-    liftIO $ do
-      rfId' `shouldBe` rfId
-      file <- B.readFile filePath
-      B.readFile path `shouldReturn` file
+    withAgent 4 agentCfg initAgentServers testDB2 $ \rcp' -> do
+      runRight_ $ xftpStartWorkers rcp' (Just recipientFiles)
+      rfProgress rcp' $ mb 18
+      ("", rfId', RFDONE path) <- rfGet rcp'
+      liftIO $ do
+        rfId' `shouldBe` rfId
+        file <- B.readFile filePath
+        B.readFile path `shouldReturn` file
 
-  -- tmp path should be removed after receiving file
-  doesDirectoryExist tmpPath `shouldReturn` False
+      threadDelay 100000
+      -- tmp path should be removed after receiving file
+      doesDirectoryExist tmpPath `shouldReturn` False
 
 testXFTPAgentReceiveCleanup :: HasCallStack => IO ()
 testXFTPAgentReceiveCleanup = withGlobalLogging logCfgNoLogs $ do
@@ -351,30 +373,27 @@ testXFTPAgentReceiveCleanup = withGlobalLogging logCfgNoLogs $ do
 
   rfd <- withXFTPServerStoreLogOn $ \_ -> do
     -- send file
-    sndr <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-    runRight $ do
+    withAgent 1 agentCfg initAgentServers testDB $ \sndr -> runRight $ do
       (_, _, rfd, _) <- testSend sndr filePath
       pure rfd
 
   -- receive file - should not succeed with server down
-  rcp <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
-  rfId <- runRight $ do
+  rfId <- withAgent 2 agentCfg initAgentServers testDB2 $ \rcp -> runRight $ do
     xftpStartWorkers rcp (Just recipientFiles)
     rfId <- xftpReceiveFile rcp 1 rfd Nothing
     liftIO $ timeout 300000 (get rcp) `shouldReturn` Nothing -- wait for worker attempt
     pure rfId
-  disposeAgentClient rcp
 
   [prefixDir] <- listDirectory recipientFiles
   let tmpPath = recipientFiles </> prefixDir </> "xftp.encrypted"
   doesDirectoryExist tmpPath `shouldReturn` True
 
-  withXFTPServerThreadOn $ \_ -> do
+  withXFTPServerThreadOn $ \_ ->
     -- receive file - should fail with AUTH error
-    rcp' <- getSMPAgentClient' 3 agentCfg initAgentServers testDB2
-    runRight_ $ xftpStartWorkers rcp' (Just recipientFiles)
-    ("", rfId', RFERR (INTERNAL "XFTP {xftpErr = AUTH}")) <- rfGet rcp'
-    rfId' `shouldBe` rfId
+    withAgent 3 agentCfg initAgentServers testDB2 $ \rcp' -> do
+      runRight_ $ xftpStartWorkers rcp' (Just recipientFiles)
+      ("", rfId', RFERR (INTERNAL "XFTP {xftpErr = AUTH}")) <- rfGet rcp'
+      rfId' `shouldBe` rfId
 
   -- tmp path should be removed after permanent error
   doesDirectoryExist tmpPath `shouldReturn` False
@@ -384,13 +403,11 @@ testXFTPAgentSendRestore = withGlobalLogging logCfgNoLogs $ do
   filePath <- createRandomFile
 
   -- send file - should not succeed with server down
-  sndr <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-  sfId <- runRight $ do
+  sfId <- withAgent 1 agentCfg initAgentServers testDB $ \sndr -> runRight $ do
     xftpStartWorkers sndr (Just senderFiles)
     sfId <- xftpSendFile sndr 1 (CF.plain filePath) 2
     liftIO $ timeout 1000000 (get sndr) `shouldReturn` Nothing -- wait for worker to encrypt and attempt to create file
     pure sfId
-  disposeAgentClient sndr
 
   dirEntries <- listDirectory senderFiles
   let prefixDir = fromJust $ find (isSuffixOf "_snd.xftp") dirEntries
@@ -399,25 +416,25 @@ testXFTPAgentSendRestore = withGlobalLogging logCfgNoLogs $ do
   doesDirectoryExist prefixPath `shouldReturn` True
   doesFileExist encPath `shouldReturn` True
 
-  withXFTPServerStoreLogOn $ \_ -> do
+  withXFTPServerStoreLogOn $ \_ ->
     -- send file - should start uploading with server up
-    sndr' <- getSMPAgentClient' 2 agentCfg initAgentServers testDB
-    runRight_ $ xftpStartWorkers sndr' (Just senderFiles)
-    ("", sfId', SFPROG _ _) <- sfGet sndr'
-    liftIO $ sfId' `shouldBe` sfId
-    disposeAgentClient sndr'
+    withAgent 2 agentCfg initAgentServers testDB $ \sndr' -> do
+      runRight_ $ xftpStartWorkers sndr' (Just senderFiles)
+      ("", sfId', SFPROG _ _) <- sfGet sndr'
+      liftIO $ sfId' `shouldBe` sfId
 
   threadDelay 100000
 
   withXFTPServerStoreLogOn $ \_ -> do
     -- send file - should continue uploading with server up
-    sndr' <- getSMPAgentClient' 3 agentCfg initAgentServers testDB
-    runRight_ $ xftpStartWorkers sndr' (Just senderFiles)
-    sfProgress sndr' $ mb 18
-    ("", sfId', SFDONE _sndDescr [rfd1, rfd2]) <- sfGet sndr'
-    liftIO $ testNoRedundancy rfd1
-    liftIO $ testNoRedundancy rfd2
-    liftIO $ sfId' `shouldBe` sfId
+    rfd1 <- withAgent 3 agentCfg initAgentServers testDB $ \sndr' -> do
+      runRight_ $ xftpStartWorkers sndr' (Just senderFiles)
+      sfProgress sndr' $ mb 18
+      ("", sfId', SFDONE _sndDescr [rfd1, rfd2]) <- sfGet sndr'
+      liftIO $ testNoRedundancy rfd1
+      liftIO $ testNoRedundancy rfd2
+      liftIO $ sfId' `shouldBe` sfId
+      pure rfd1
 
     -- prefix path should be removed after sending file
     threadDelay 100000
@@ -425,18 +442,16 @@ testXFTPAgentSendRestore = withGlobalLogging logCfgNoLogs $ do
     doesFileExist encPath `shouldReturn` False
 
     -- receive file
-    rcp <- getSMPAgentClient' 4 agentCfg initAgentServers testDB2
-    runRight_ . void $
-      testReceive rcp rfd1 filePath
+    withAgent 4 agentCfg initAgentServers testDB2 $ \rcp ->
+      runRight_ . void $ testReceive rcp rfd1 filePath
 
 testXFTPAgentSendCleanup :: HasCallStack => IO ()
 testXFTPAgentSendCleanup = withGlobalLogging logCfgNoLogs $ do
   filePath <- createRandomFile
 
-  sfId <- withXFTPServerStoreLogOn $ \_ -> do
+  sfId <- withXFTPServerStoreLogOn $ \_ ->
     -- send file
-    sndr <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-    sfId <- runRight $ do
+    withAgent 1 agentCfg initAgentServers testDB $ \sndr -> runRight $ do
       xftpStartWorkers sndr (Just senderFiles)
       sfId <- xftpSendFile sndr 1 (CF.plain filePath) 2
       -- wait for progress events for 5 out of 6 chunks - at this point all chunks should be created on the server
@@ -444,8 +459,6 @@ testXFTPAgentSendCleanup = withGlobalLogging logCfgNoLogs $ do
         (_, _, SFPROG _ _) <- sfGet sndr
         pure ()
       pure sfId
-    disposeAgentClient sndr
-    pure sfId
 
   dirEntries <- listDirectory senderFiles
   let prefixDir = fromJust $ find (isSuffixOf "_snd.xftp") dirEntries
@@ -454,16 +467,16 @@ testXFTPAgentSendCleanup = withGlobalLogging logCfgNoLogs $ do
   doesDirectoryExist prefixPath `shouldReturn` True
   doesFileExist encPath `shouldReturn` True
 
-  withXFTPServerThreadOn $ \_ -> do
+  withXFTPServerThreadOn $ \_ ->
     -- send file - should fail with AUTH error
-    sndr' <- getSMPAgentClient' 2 agentCfg initAgentServers testDB
-    runRight_ $ xftpStartWorkers sndr' (Just senderFiles)
-    ("", sfId', SFERR (INTERNAL "XFTP {xftpErr = AUTH}")) <- sfGet sndr'
-    sfId' `shouldBe` sfId
+    withAgent 2 agentCfg initAgentServers testDB $ \sndr' -> do
+      runRight_ $ xftpStartWorkers sndr' (Just senderFiles)
+      ("", sfId', SFERR (INTERNAL "XFTP {xftpErr = AUTH}")) <- sfGet sndr'
+      sfId' `shouldBe` sfId
 
-    -- prefix path should be removed after permanent error
-    doesDirectoryExist prefixPath `shouldReturn` False
-    doesFileExist encPath `shouldReturn` False
+  -- prefix path should be removed after permanent error
+  doesDirectoryExist prefixPath `shouldReturn` False
+  doesFileExist encPath `shouldReturn` False
 
 testXFTPAgentDelete :: HasCallStack => IO ()
 testXFTPAgentDelete = withGlobalLogging logCfgNoLogs $
@@ -471,32 +484,30 @@ testXFTPAgentDelete = withGlobalLogging logCfgNoLogs $
     filePath <- createRandomFile
 
     -- send file
-    sndr <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-    (sfId, sndDescr, rfd1, rfd2) <- runRight $ testSend sndr filePath
+    withAgent 1 agentCfg initAgentServers testDB $ \sndr -> do
+      (sfId, sndDescr, rfd1, rfd2) <- runRight $ testSend sndr filePath
 
-    -- receive file
-    rcp1 <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
-    runRight_ . void $
-      testReceive rcp1 rfd1 filePath
+      -- receive file
+      withAgent 2 agentCfg initAgentServers testDB2 $ \rcp1 -> do
+        runRight_ . void $ testReceive rcp1 rfd1 filePath
 
-    length <$> listDirectory xftpServerFiles `shouldReturn` 6
+        length <$> listDirectory xftpServerFiles `shouldReturn` 6
 
-    -- delete file
-    runRight_ $ xftpStartWorkers sndr (Just senderFiles)
-    xftpDeleteSndFileRemote sndr 1 sfId sndDescr
-    Nothing <- 100000 `timeout` sfGet sndr
-    disposeAgentClient rcp1
+        -- delete file
+        runRight_ $ xftpStartWorkers sndr (Just senderFiles)
+        xftpDeleteSndFileRemote sndr 1 sfId sndDescr
+        Nothing <- 100000 `timeout` sfGet sndr
+        pure ()
 
-    threadDelay 1000000
-    length <$> listDirectory xftpServerFiles `shouldReturn` 0
+      threadDelay 1000000
+      length <$> listDirectory xftpServerFiles `shouldReturn` 0
 
-    -- receive file - should fail with AUTH error
-    rcp2 <- getSMPAgentClient' 3 agentCfg initAgentServers testDB2
-    runRight $ do
-      xftpStartWorkers rcp2 (Just recipientFiles)
-      rfId <- xftpReceiveFile rcp2 1 rfd2 Nothing
-      ("", rfId', RFERR (INTERNAL "XFTP {xftpErr = AUTH}")) <- rfGet rcp2
-      liftIO $ rfId' `shouldBe` rfId
+      -- receive file - should fail with AUTH error
+      withAgent 3 agentCfg initAgentServers testDB2 $ \rcp2 -> runRight $ do
+        xftpStartWorkers rcp2 (Just recipientFiles)
+        rfId <- xftpReceiveFile rcp2 1 rfd2 Nothing
+        ("", rfId', RFERR (INTERNAL "XFTP {xftpErr = AUTH}")) <- rfGet rcp2
+        liftIO $ rfId' `shouldBe` rfId
 
 testXFTPAgentDeleteRestore :: HasCallStack => IO ()
 testXFTPAgentDeleteRestore = withGlobalLogging logCfgNoLogs $ do
@@ -504,42 +515,36 @@ testXFTPAgentDeleteRestore = withGlobalLogging logCfgNoLogs $ do
 
   (sfId, sndDescr, rfd2) <- withXFTPServerStoreLogOn $ \_ -> do
     -- send file
-    sndr <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-    (sfId, sndDescr, rfd1, rfd2) <- runRight $ testSend sndr filePath
+    withAgent 1 agentCfg initAgentServers testDB $ \sndr -> do
+      (sfId, sndDescr, rfd1, rfd2) <- runRight $ testSend sndr filePath
 
-    -- receive file
-    rcp1 <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
-    runRight_ . void $
-      testReceive rcp1 rfd1 filePath
-    disposeAgentClient rcp1
-    disposeAgentClient sndr
-    pure (sfId, sndDescr, rfd2)
+      -- receive file
+      withAgent 2 agentCfg initAgentServers testDB2 $ \rcp1 ->
+        runRight_ . void $ testReceive rcp1 rfd1 filePath
+      pure (sfId, sndDescr, rfd2)
 
   -- delete file - should not succeed with server down
-  sndr <- getSMPAgentClient' 3 agentCfg initAgentServers testDB
-  runRight_ $ xftpStartWorkers sndr (Just senderFiles)
-  xftpDeleteSndFileRemote sndr 1 sfId sndDescr
-  timeout 300000 (get sndr) `shouldReturn` Nothing -- wait for worker attempt
-  disposeAgentClient sndr
-
+  withAgent 3 agentCfg initAgentServers testDB $ \sndr -> do
+    runRight_ $ xftpStartWorkers sndr (Just senderFiles)
+    xftpDeleteSndFileRemote sndr 1 sfId sndDescr
+    timeout 300000 (get sndr) `shouldReturn` Nothing -- wait for worker attempt
   threadDelay 300000
   length <$> listDirectory xftpServerFiles `shouldReturn` 6
 
   withXFTPServerStoreLogOn $ \_ -> do
     -- delete file - should succeed with server up
-    sndr' <- getSMPAgentClient' 4 agentCfg initAgentServers testDB
-    runRight_ $ xftpStartWorkers sndr' (Just senderFiles)
+    withAgent 4 agentCfg initAgentServers testDB $ \sndr' -> do
+      runRight_ $ xftpStartWorkers sndr' (Just senderFiles)
 
-    threadDelay 1000000
-    length <$> listDirectory xftpServerFiles `shouldReturn` 0
+      threadDelay 1000000
+      length <$> listDirectory xftpServerFiles `shouldReturn` 0
 
-    -- receive file - should fail with AUTH error
-    rcp2 <- getSMPAgentClient' 5 agentCfg initAgentServers testDB3
-    runRight $ do
-      xftpStartWorkers rcp2 (Just recipientFiles)
-      rfId <- xftpReceiveFile rcp2 1 rfd2 Nothing
-      ("", rfId', RFERR (INTERNAL "XFTP {xftpErr = AUTH}")) <- rfGet rcp2
-      liftIO $ rfId' `shouldBe` rfId
+      -- receive file - should fail with AUTH error
+      withAgent 5 agentCfg initAgentServers testDB3 $ \rcp2 -> runRight $ do
+        xftpStartWorkers rcp2 (Just recipientFiles)
+        rfId <- xftpReceiveFile rcp2 1 rfd2 Nothing
+        ("", rfId', RFERR (INTERNAL "XFTP {xftpErr = AUTH}")) <- rfGet rcp2
+        liftIO $ rfId' `shouldBe` rfId
 
 testXFTPAgentDeleteOnServer :: HasCallStack => IO ()
 testXFTPAgentDeleteOnServer = withGlobalLogging logCfgNoLogs $
@@ -547,36 +552,36 @@ testXFTPAgentDeleteOnServer = withGlobalLogging logCfgNoLogs $
     filePath1 <- createRandomFile' "testfile1"
 
     -- send file 1
-    sndr <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-    (_, _, rfd1_1, rfd1_2) <- runRight $ testSend sndr filePath1
+    withAgent 1 agentCfg initAgentServers testDB $ \sndr -> do
+      (_, _, rfd1_1, rfd1_2) <- runRight $ testSend sndr filePath1
 
-    -- receive file 1 successfully
-    rcp <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
-    runRight_ . void $
-      testReceive rcp rfd1_1 filePath1
+      -- receive file 1 successfully
+      withAgent 2 agentCfg initAgentServers testDB2 $ \rcp -> do
+        runRight_ . void $ testReceive rcp rfd1_1 filePath1
 
-    serverFiles <- listDirectory xftpServerFiles
-    length serverFiles `shouldBe` 6
+        serverFiles <- listDirectory xftpServerFiles
+        length serverFiles `shouldBe` 6
 
-    -- delete file 1 on server from file system
-    forM_ serverFiles (\file -> removeFile (xftpServerFiles </> file))
+        -- delete file 1 on server from file system
+        forM_ serverFiles (\file -> removeFile (xftpServerFiles </> file))
 
-    threadDelay 1000000
-    length <$> listDirectory xftpServerFiles `shouldReturn` 0
+        threadDelay 1000000
+        length <$> listDirectory xftpServerFiles `shouldReturn` 0
 
-    -- create and send file 2
-    filePath2 <- createRandomFile' "testfile2"
-    (_, _, rfd2, _) <- runRight $ testSend sndr filePath2
+        -- create and send file 2
+        filePath2 <- createRandomFile' "testfile2"
+        (_, _, rfd2, _) <- runRight $ testSend sndr filePath2
 
-    length <$> listDirectory xftpServerFiles `shouldReturn` 6
+        length <$> listDirectory xftpServerFiles `shouldReturn` 6
 
-    runRight_ . void $ do
-      -- receive file 1 again
-      -- TODO should fail with AUTH error
-      _rfId1 <- xftpReceiveFile rcp 1 rfd1_2 Nothing
+        runRight_ . void $ do
+          -- receive file 1 again
+          rfId1 <- xftpReceiveFile rcp 1 rfd1_2 Nothing
+          ("", rfId1', RFERR (INTERNAL "XFTP {xftpErr = AUTH}")) <- rfGet rcp
+          liftIO $ rfId1 `shouldBe` rfId1'
 
-      -- receive file 2
-      testReceive' rcp rfd2 filePath2
+          -- receive file 2
+          testReceive' rcp rfd2 filePath2
 
 testXFTPAgentExpiredOnServer :: HasCallStack => IO ()
 testXFTPAgentExpiredOnServer = withGlobalLogging logCfgNoLogs $ do
@@ -585,46 +590,43 @@ testXFTPAgentExpiredOnServer = withGlobalLogging logCfgNoLogs $ do
     filePath1 <- createRandomFile' "testfile1"
 
     -- send file 1
-    sndr <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-    (_, _, rfd1_1, rfd1_2) <- runRight $ testSend sndr filePath1
+    withAgent 1 agentCfg initAgentServers testDB $ \sndr -> do
+      (_, _, rfd1_1, rfd1_2) <- runRight $ testSend sndr filePath1
 
-    -- receive file 1 successfully
-    rcp <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
-    runRight_ . void $
-      testReceive rcp rfd1_1 filePath1
+      -- receive file 1 successfully
+      withAgent 2 agentCfg initAgentServers testDB2 $ \rcp -> do
+        runRight_ . void $ testReceive rcp rfd1_1 filePath1
 
-    serverFiles <- listDirectory xftpServerFiles
-    length serverFiles `shouldBe` 6
+        serverFiles <- listDirectory xftpServerFiles
+        length serverFiles `shouldBe` 6
 
-    -- wait until file 1 expires on server
-    forM_ serverFiles (\file -> removeFile (xftpServerFiles </> file))
+        -- wait until file 1 expires on server
+        forM_ serverFiles (\file -> removeFile (xftpServerFiles </> file))
 
-    threadDelay 3500000
-    length <$> listDirectory xftpServerFiles `shouldReturn` 0
+        threadDelay 3500000
+        length <$> listDirectory xftpServerFiles `shouldReturn` 0
 
-    -- receive file 1 again - should fail with AUTH error
-    runRight $ do
-      rfId <- xftpReceiveFile rcp 1 rfd1_2 Nothing
-      ("", rfId', RFERR (INTERNAL "XFTP {xftpErr = AUTH}")) <- rfGet rcp
-      liftIO $ rfId' `shouldBe` rfId
+        -- receive file 1 again - should fail with AUTH error
+        runRight $ do
+          rfId <- xftpReceiveFile rcp 1 rfd1_2 Nothing
+          ("", rfId', RFERR (INTERNAL "XFTP {xftpErr = AUTH}")) <- rfGet rcp
+          liftIO $ rfId' `shouldBe` rfId
 
-    -- create and send file 2
-    filePath2 <- createRandomFile' "testfile2"
-    (_, _, rfd2, _) <- runRight $ testSend sndr filePath2
+        -- create and send file 2
+        filePath2 <- createRandomFile' "testfile2"
+        (_, _, rfd2, _) <- runRight $ testSend sndr filePath2
 
-    length <$> listDirectory xftpServerFiles `shouldReturn` 6
+        length <$> listDirectory xftpServerFiles `shouldReturn` 6
 
-    -- receive file 2 successfully
-    runRight_ . void $
-      testReceive' rcp rfd2 filePath2
+        -- receive file 2 successfully
+        runRight_ . void $ testReceive' rcp rfd2 filePath2
 
 testXFTPAgentRequestAdditionalRecipientIDs :: HasCallStack => IO ()
 testXFTPAgentRequestAdditionalRecipientIDs = withXFTPServer $ do
   filePath <- createRandomFile
 
   -- send file
-  sndr <- getSMPAgentClient' 1 agentCfg initAgentServers testDB
-  rfds <- runRight $ do
+  rfds <- withAgent 1 agentCfg initAgentServers testDB $ \sndr -> runRight $ do
     xftpStartWorkers sndr (Just senderFiles)
     sfId <- xftpSendFile sndr 1 (CF.plain filePath) 500
     sfProgress sndr $ mb 18
@@ -638,8 +640,7 @@ testXFTPAgentRequestAdditionalRecipientIDs = withXFTPServer $ do
 
   -- receive file using different descriptions
   -- ! revise number of recipients and indexes if xftpMaxRecipientsPerRequest is changed
-  rcp <- getSMPAgentClient' 2 agentCfg initAgentServers testDB2
-  runRight_ $ do
+  withAgent 2 agentCfg initAgentServers testDB2 $ \rcp -> runRight_ $ do
     void $ testReceive rcp (head rfds) filePath
     void $ testReceive rcp (rfds !! 99) filePath
     void $ testReceive rcp (rfds !! 299) filePath
@@ -647,6 +648,7 @@ testXFTPAgentRequestAdditionalRecipientIDs = withXFTPServer $ do
 
 testXFTPServerTest :: HasCallStack => Maybe BasicAuth -> XFTPServerWithAuth -> IO (Maybe ProtocolTestFailure)
 testXFTPServerTest newFileBasicAuth srv =
-  withXFTPServerCfg testXFTPServerConfig {newFileBasicAuth, xftpPort = xftpTestPort2} $ \_ -> do
-    a <- getSMPAgentClient' 1 agentCfg initAgentServers testDB -- initially passed server is not running
-    testProtocolServer a 1 srv
+  withXFTPServerCfg testXFTPServerConfig {newFileBasicAuth, xftpPort = xftpTestPort2} $ \_ ->
+    -- initially passed server is not running
+    withAgent 1 agentCfg initAgentServers testDB $ \a ->
+      testProtocolServer a 1 srv

tests/XFTPClient.hs

@@ -1,19 +1,21 @@
 {-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 
 module XFTPClient where
 
-import Control.Concurrent (ThreadId)
+import Control.Concurrent (ThreadId, threadDelay)
 import Data.String (fromString)
 import Network.Socket (ServiceName)
 import SMPClient (serverBracket)
 import Simplex.FileTransfer.Client
 import Simplex.FileTransfer.Description
 import Simplex.FileTransfer.Server (runXFTPServerBlocking)
-import Simplex.FileTransfer.Server.Env (XFTPServerConfig (..), defaultFileExpiration, defaultInactiveClientExpiration)
+import Simplex.FileTransfer.Server.Env (XFTPServerConfig (..), defaultFileExpiration, defaultInactiveClientExpiration, supportedXFTPhandshakes)
 import Simplex.Messaging.Protocol (XFTPServer)
+import Simplex.Messaging.Transport (ALPN)
 import Simplex.Messaging.Transport.Server
 import Test.Hspec
 
@@ -52,7 +54,7 @@ withXFTPServerCfg :: HasCallStack => XFTPServerConfig -> (HasCallStack => Thread
 withXFTPServerCfg cfg =
   serverBracket
     (`runXFTPServerBlocking` cfg)
-    (pure ())
+    (threadDelay 10000)
 
 withXFTPServerThreadOn :: HasCallStack => (HasCallStack => ThreadId -> IO a) -> IO a
 withXFTPServerThreadOn = withXFTPServerCfg testXFTPServerConfig
@@ -94,7 +96,10 @@ testXFTPStatsBackupFile :: FilePath
 testXFTPStatsBackupFile = "tests/tmp/xftp-server-stats.log"
 
 testXFTPServerConfig :: XFTPServerConfig
-testXFTPServerConfig =
+testXFTPServerConfig = testXFTPServerConfig_ (Just supportedXFTPhandshakes)
+
+testXFTPServerConfig_ :: Maybe [ALPN] -> XFTPServerConfig
+testXFTPServerConfig_ alpn =
   XFTPServerConfig
     { xftpPort = xftpTestPort,
       controlPort = Nothing,
@@ -117,14 +122,17 @@ testXFTPServerConfig =
       logStatsStartTime = 0,
       serverStatsLogFile = "tests/tmp/xftp-server-stats.daily.log",
       serverStatsBackupFile = Nothing,
-      transportConfig = defaultTransportServerConfig
+      transportConfig = defaultTransportServerConfig {alpn}
     }
 
 testXFTPClientConfig :: XFTPClientConfig
 testXFTPClientConfig = defaultXFTPClientConfig
 
 testXFTPClient :: HasCallStack => (HasCallStack => XFTPClient -> IO a) -> IO a
-testXFTPClient client =
-  getXFTPClient (1, testXFTPServer, Nothing) testXFTPClientConfig (\_ -> pure ()) >>= \case
+testXFTPClient = testXFTPClientWith testXFTPClientConfig
+
+testXFTPClientWith :: HasCallStack => XFTPClientConfig -> (HasCallStack => XFTPClient -> IO a) -> IO a
+testXFTPClientWith cfg client =
+  getXFTPClient (1, testXFTPServer, Nothing) cfg (\_ -> pure ()) >>= \case
     Right c -> client c
     Left e -> error $ show e

tests/XFTPServerTests.hs

@@ -12,6 +12,7 @@ import Control.Exception (SomeException)
 import Control.Monad
 import Control.Monad.Except
 import Control.Monad.IO.Unlift
+import qualified Data.ByteString.Base64.URL as B64
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
 import qualified Data.ByteString.Lazy.Char8 as LB
@@ -21,11 +22,10 @@ import Simplex.FileTransfer.Client
 import Simplex.FileTransfer.Description (kb)
 import Simplex.FileTransfer.Protocol (FileInfo (..))
 import Simplex.FileTransfer.Server.Env (XFTPServerConfig (..))
-import Simplex.FileTransfer.Transport (XFTPRcvChunkSpec (..), XFTPErrorType (..))
+import Simplex.FileTransfer.Transport (XFTPErrorType (..), XFTPRcvChunkSpec (..))
 import Simplex.Messaging.Client (ProtocolClientError (..))
 import qualified Simplex.Messaging.Crypto as C
 import qualified Simplex.Messaging.Crypto.Lazy as LC
-import qualified Simplex.Messaging.Encoding.Base64.URL as U
 import Simplex.Messaging.Protocol (BasicAuth, SenderId)
 import Simplex.Messaging.Server.Expiration (ExpirationConfig (..))
 import System.Directory (createDirectoryIfMissing, removeDirectoryRecursive, removeFile)
@@ -75,7 +75,7 @@ createTestChunk fp = do
   pure bytes
 
 readChunk :: SenderId -> IO ByteString
-readChunk sId = B.readFile (xftpServerFiles </> B.unpack (U.encode sId))
+readChunk sId = B.readFile (xftpServerFiles </> B.unpack (B64.encode sId))
 
 testFileChunkDelivery :: Expectation
 testFileChunkDelivery = xftpTest $ \c -> runRight_ $ runTestFileChunkDelivery c c

tests/fixtures/ca2.crt

@@ -0,0 +1,12 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----

tests/fixtures/ca2.key

@@ -0,0 +1,4 @@
+-----BEGIN PRIVATE KEY-----
+MEcCAQAwBQYDK2VxBDsEOcBpozc2TnAf6lQaxN5bA6JdbKWuxUecsW9P2dzncCnB
+/alBtYXqW6SprBj1DqzeZyU4rQ7OqFrgBw==
+-----END PRIVATE KEY-----

tests/fixtures/server2.crt

@@ -0,0 +1,12 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----

tests/fixtures/server2.key

@@ -0,0 +1,4 @@
+-----BEGIN PRIVATE KEY-----
+MEcCAQAwBQYDK2VxBDsEObrN+1gIRcwmahmitb6ltVoZjjnVoHj0/1waYkjmMtQl
+PiGhWP5/B6Y1fLH/YiO/tfX2YPGCOJJSJQ==
+-----END PRIVATE KEY-----

tests/fixtures/ss.crt

@@ -0,0 +1,13 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----

tests/fixtures/ss.key

@@ -0,0 +1,6 @@
+-----BEGIN PRIVATE KEY-----
+MIG2AgEAMBAGByqGSM49AgEGBSuBBAAiBIGeMIGbAgEBBDBH/6IpMqcKFrXNU8Nb
+QFvdzQOJtfoAEEDRBmMqbihPrCgbtCJ3FIVnxqGlFIXADaqhZANiAATCK5sj+BQ2
+Pj/E7pb/AXKeVO0JR4oKDluiT0T0xE0xQZdnu7fVAKWvxAGJfNOZpGiHawyc3bQK
+pLbR5j5uL13QgrmpcVUWf7Ybab3TaHMciTg/QVb90Cqorkhrghh6fps=
+-----END PRIVATE KEY-----