From 2f43b432254808ecac623d34fb553987d012114c Mon Sep 17 00:00:00 2001
From: Evgeny Poberezkin <evgeny@poberezkin.com>
Date: Mon, 15 Apr 2024 13:47:48 +0100
Subject: [PATCH] parameterize transport handle with transport peer to include
 server certificate (#1100)

* parameterize transport handle with transport peer to include server certificate

* include server certificate into THandle

* load server chain and sign key

* fix key type

* fix for 8.10

---------

Co-authored-by: Alexander Bondarenko <486682+dpwiz@users.noreply.github.com>
Co-authored-by: IC Rainbow <aenor.realm@gmail.com>
---
 src/Simplex/FileTransfer/Client.hs            | 13 ++--
 src/Simplex/FileTransfer/Protocol.hs          | 12 ++--
 src/Simplex/FileTransfer/Server.hs            | 16 ++---
 src/Simplex/FileTransfer/Transport.hs         |  9 +--
 src/Simplex/Messaging/Client.hs               | 14 ++--
 src/Simplex/Messaging/Notifications/Server.hs | 10 +--
 .../Messaging/Notifications/Server/Env.hs     |  8 +--
 .../Messaging/Notifications/Transport.hs      | 44 +++++++-----
 src/Simplex/Messaging/Protocol.hs             | 22 +++---
 src/Simplex/Messaging/Server.hs               | 18 ++---
 src/Simplex/Messaging/Transport.hs            | 70 ++++++++++++-------
 tests/CoreTests/BatchingTests.hs              | 21 ++++--
 tests/NtfClient.hs                            |  8 +--
 tests/NtfServerTests.hs                       |  6 +-
 tests/SMPClient.hs                            | 32 ++++-----
 tests/ServerTests.hs                          | 35 +++++-----
 16 files changed, 191 insertions(+), 147 deletions(-)

diff --git a/src/Simplex/FileTransfer/Client.hs b/src/Simplex/FileTransfer/Client.hs
index fcb54aece..a223d492e 100644
--- a/src/Simplex/FileTransfer/Client.hs
+++ b/src/Simplex/FileTransfer/Client.hs
@@ -51,7 +51,7 @@ import Simplex.Messaging.Protocol
     RecipientId,
     SenderId,
   )
-import Simplex.Messaging.Transport (ALPN, HandshakeError (VERSION), THandleAuth (..), THandleParams (..), TransportError (..), supportedParameters)
+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
@@ -64,7 +64,7 @@ import UnliftIO.Directory
 data XFTPClient = XFTPClient
   { http2Client :: HTTP2Client,
     transportSession :: TransportSession FileResponse,
-    thParams :: THandleParams XFTPVersion,
+    thParams :: THandleParams XFTPVersion 'TClient,
     config :: XFTPClientConfig
   }
 
@@ -120,19 +120,21 @@ getXFTPClient g transportSession@(_, srv, _) config@XFTPClientConfig {clientALPN
   atomically $ writeTVar clientVar $ Just c
   pure c
 
-xftpClientHandshakeV1 :: TVar ChaChaDRG -> VersionRangeXFTP -> C.KeyHash -> HTTP2Client -> THandleParamsXFTP -> ExceptT XFTPClientError IO THandleParamsXFTP
+xftpClientHandshakeV1 :: TVar ChaChaDRG -> VersionRangeXFTP -> C.KeyHash -> HTTP2Client -> THandleParamsXFTP 'TClient -> ExceptT XFTPClientError IO (THandleParamsXFTP 'TClient)
 xftpClientHandshakeV1 g serverVRange keyHash@(C.KeyHash kh) c@HTTP2Client {sessionId, serverKey} thParams0 = do
-  shs <- getServerHandshake
+  shs@XFTPServerHandshake {authPubKey = ck} <- getServerHandshake
   (v, sk) <- processServerHandshake shs
   (k, pk) <- atomically $ C.generateKeyPair g
   sendClientHandshake XFTPClientHandshake {xftpVersion = v, keyHash, authPubKey = k}
-  pure thParams0 {thAuth = Just THandleAuth {peerPubKey = sk, privKey = pk}, thVersion = v}
+  pure thParams0 {thAuth = Just THAuthClient {serverPeerPubKey = sk, serverCertKey = ck, clientPrivKey = pk}, 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
@@ -145,6 +147,7 @@ xftpClientHandshakeV1 g serverVRange keyHash@(C.KeyHash kh) c@HTTP2Client {sessi
               _ -> 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'
diff --git a/src/Simplex/FileTransfer/Protocol.hs b/src/Simplex/FileTransfer/Protocol.hs
index f970fdfcc..418e48482 100644
--- a/src/Simplex/FileTransfer/Protocol.hs
+++ b/src/Simplex/FileTransfer/Protocol.hs
@@ -39,8 +39,8 @@ import Simplex.Messaging.Protocol
     ProtocolErrorType (..),
     ProtocolMsgTag (..),
     ProtocolType (..),
-    RcvPublicDhKey,
     RcvPublicAuthKey,
+    RcvPublicDhKey,
     RecipientId,
     SenderId,
     SentRawTransmission,
@@ -48,14 +48,14 @@ import Simplex.Messaging.Protocol
     SndPublicAuthKey,
     Transmission,
     TransmissionForAuth (..),
-    encodeTransmissionForAuth,
     encodeTransmission,
+    encodeTransmissionForAuth,
     messageTagP,
     tDecodeParseValidate,
     tEncodeBatch1,
     tParse,
   )
-import Simplex.Messaging.Transport (THandleParams (..), TransportError (..))
+import Simplex.Messaging.Transport (THandleParams (..), TransportError (..), TransportPeer (..))
 import Simplex.Messaging.Util ((<$?>))
 
 xftpBlockSize :: Int
@@ -325,12 +325,12 @@ 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 :: ProtocolEncoding XFTPVersion e c => THandleParams XFTPVersion 'TClient -> C.APrivateAuthKey -> Transmission c -> Either TransportError ByteString
 xftpEncodeAuthTransmission thParams@THandleParams {thAuth} pKey (corrId, fId, msg) = do
   let TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth thParams (corrId, fId, msg)
   xftpEncodeBatch1 . (,tToSend) =<< authTransmission thAuth (Just pKey) corrId tForAuth
 
-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)
@@ -339,7 +339,7 @@ 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
diff --git a/src/Simplex/FileTransfer/Server.hs b/src/Simplex/FileTransfer/Server.hs
index b426360ea..b3bee134f 100644
--- a/src/Simplex/FileTransfer/Server.hs
+++ b/src/Simplex/FileTransfer/Server.hs
@@ -56,7 +56,7 @@ import Simplex.Messaging.Server.Expiration
 import Simplex.Messaging.Server.Stats
 import Simplex.Messaging.TMap (TMap)
 import qualified Simplex.Messaging.TMap as TM
-import Simplex.Messaging.Transport (SessionId, THandleAuth (..), THandleParams (..))
+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)
@@ -75,7 +75,7 @@ import qualified UnliftIO.Exception as E
 type M a = ReaderT XFTPEnv IO a
 
 data XFTPTransportRequest = XFTPTransportRequest
-  { thParams :: THandleParamsXFTP,
+  { thParams :: THandleParamsXFTP 'TServer,
     reqBody :: HTTP2Body,
     request :: H.Request,
     sendResponse :: H.Response -> IO ()
@@ -91,7 +91,7 @@ runXFTPServerBlocking started cfg = newXFTPServerEnv cfg >>= runReaderT (xftpSer
 
 data Handshake
   = HandshakeSent C.PrivateKeyX25519
-  | HandshakeAccepted THandleAuth VersionXFTP
+  | HandshakeAccepted (THandleAuth 'TServer) VersionXFTP
 
 xftpServer :: XFTPServerConfig -> TMVar Bool -> M ()
 xftpServer cfg@XFTPServerConfig {xftpPort, transportConfig, inactiveClientExpiration, fileExpiration} started = do
@@ -120,7 +120,7 @@ xftpServer cfg@XFTPServerConfig {xftpPort, transportConfig, inactiveClientExpira
               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))
+    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
@@ -138,18 +138,18 @@ xftpServer cfg@XFTPServerConfig {xftpPort, transportConfig, inactiveClientExpira
           shs <- encodeXftp hs
           liftIO . sendResponse $ H.responseBuilder N.ok200 [] shs
           pure Nothing
-        processClientHandshake privKey = do
+        processClientHandshake pk = do
           unless (B.length bodyHead == xftpBlockSize) $ throwError HANDSHAKE
           body <- liftHS $ C.unPad bodyHead
           XFTPClientHandshake {xftpVersion, keyHash, authPubKey} <- liftHS $ smpDecode body
           kh <- asks serverIdentity
           unless (keyHash == kh) $ throwError HANDSHAKE
           unless (xftpVersion `isCompatible` supportedFileServerVRange) $ throwError HANDSHAKE
-          let auth = THandleAuth {peerPubKey = authPubKey, privKey}
+          let auth = THAuthServer {clientPeerPubKey = authPubKey, serverPrivKey = pk}
           atomically $ TM.insert sessionId (HandshakeAccepted auth xftpVersion) sessions
           liftIO . sendResponse $ H.responseNoBody N.ok200 []
           pure Nothing
-        sendError :: XFTPErrorType -> M (Maybe (THandleParams XFTPVersion))
+        sendError :: XFTPErrorType -> M (Maybe (THandleParams XFTPVersion 'TServer))
         sendError err = do
           runExceptT (encodeXftp err) >>= \case
             Right bs -> liftIO . sendResponse $ H.responseBuilder N.ok200 [] bs
@@ -326,7 +326,7 @@ processRequest XFTPTransportRequest {thParams, reqBody = body@HTTP2Body {bodyHea
 
 data VerificationResult = VRVerified XFTPRequest | VRFailed
 
-verifyXFTPTransmission :: Maybe (THandleAuth, C.CbNonce) -> Maybe TransmissionAuth -> ByteString -> XFTPFileId -> FileCmd -> M VerificationResult
+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
diff --git a/src/Simplex/FileTransfer/Transport.hs b/src/Simplex/FileTransfer/Transport.hs
index d8bb72f6b..041069e98 100644
--- a/src/Simplex/FileTransfer/Transport.hs
+++ b/src/Simplex/FileTransfer/Transport.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE DataKinds #-}
 {-# LANGUAGE DuplicateRecordFields #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE MultiWayIf #-}
@@ -51,7 +52,7 @@ import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
 import Simplex.Messaging.Parsers
 import Simplex.Messaging.Protocol (CommandError)
-import Simplex.Messaging.Transport (HandshakeError (..), SessionId, THandle (..), THandleParams (..), 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
@@ -76,8 +77,8 @@ type VersionRangeXFTP = VersionRange XFTPVersion
 pattern VersionXFTP :: Word16 -> VersionXFTP
 pattern VersionXFTP v = Version v
 
-type THandleXFTP c = THandle XFTPVersion c
-type THandleParamsXFTP = THandleParams XFTPVersion
+type THandleXFTP c p = THandle XFTPVersion c p
+type THandleParamsXFTP p = THandleParams XFTPVersion p
 
 initialXFTPVersion :: VersionXFTP
 initialXFTPVersion = VersionXFTP 1
@@ -89,7 +90,7 @@ supportedFileServerVRange :: VersionRangeXFTP
 supportedFileServerVRange = mkVersionRange initialXFTPVersion currentXFTPVersion
 
 -- XFTP protocol does not support handshake
-xftpClientHandshakeStub :: c -> C.KeyPairX25519 -> C.KeyHash -> VersionRangeXFTP -> ExceptT TransportError IO (THandle XFTPVersion c)
+xftpClientHandshakeStub :: c -> C.KeyPairX25519 -> C.KeyHash -> VersionRangeXFTP -> ExceptT TransportError IO (THandle XFTPVersion c 'TClient)
 xftpClientHandshakeStub _c _ks _keyHash _xftpVRange = throwError $ TEHandshake VERSION
 
 data XFTPServerHandshake = XFTPServerHandshake
diff --git a/src/Simplex/Messaging/Client.hs b/src/Simplex/Messaging/Client.hs
index e0591b14d..61ec96003 100644
--- a/src/Simplex/Messaging/Client.hs
+++ b/src/Simplex/Messaging/Client.hs
@@ -84,8 +84,8 @@ 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
@@ -119,7 +119,7 @@ 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
   }
@@ -138,7 +138,7 @@ 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
@@ -387,10 +387,10 @@ 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 ()
@@ -733,13 +733,13 @@ mkTransmission ProtocolClient {thParams, client_ = PClient {clientCorrId, sentCo
       TM.insert corrId r sentCommands
       pure r
 
-authTransmission :: Maybe THandleAuth -> Maybe C.APrivateAuthKey -> CorrId -> ByteString -> Either TransportError (Maybe TransmissionAuth)
+authTransmission :: Maybe (THandleAuth 'TClient) -> Maybe C.APrivateAuthKey -> CorrId -> ByteString -> Either TransportError (Maybe TransmissionAuth)
 authTransmission thAuth pKey_ (CorrId corrId) 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 (C.cbNonce corrId) t
         Nothing -> Left TENoServerAuth
       C.SEd25519 -> sign pk
       C.SEd448 -> sign pk
diff --git a/src/Simplex/Messaging/Notifications/Server.hs b/src/Simplex/Messaging/Notifications/Server.hs
index 55ab40718..55bdb07eb 100644
--- a/src/Simplex/Messaging/Notifications/Server.hs
+++ b/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)
@@ -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
diff --git a/src/Simplex/Messaging/Notifications/Server/Env.hs b/src/Simplex/Messaging/Notifications/Server/Env.hs
index 4a93a8a34..5bcd72f3d 100644
--- a/src/Simplex/Messaging/Notifications/Server/Env.hs
+++ b/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
diff --git a/src/Simplex/Messaging/Notifications/Transport.hs b/src/Simplex/Messaging/Notifications/Transport.hs
index bc68fab03..d4a4a4cbe 100644
--- a/src/Simplex/Messaging/Notifications/Transport.hs
+++ b/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,
@@ -111,7 +112,7 @@ encodeNtfAuthPubKey v k
   | otherwise = ""
 
 -- | 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
@@ -121,11 +122,11 @@ ntfServerHandshake serverSignKey c (k, pk) kh ntfVRange = do
       | keyHash /= kh ->
           throwError $ TEHandshake IDENTITY
       | v `isCompatible` ntfVRange ->
-          pure $ ntfThHandle th v pk k'
+          pure $ ntfThHandleServer th v pk k'
       | 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 :: forall c. Transport c => c -> C.KeyPairX25519 -> C.KeyHash -> VersionRangeNTF -> ExceptT TransportError IO (THandleNTF c 'TClient)
 ntfClientHandshake c (k, pk) keyHash ntfVRange = do
   let th@THandle {params = THandleParams {sessionId}} = ntfTHandle c
   NtfServerHandshake {sessionId = sessId, ntfVersionRange, authPubKey = sk'} <- getHandshake th
@@ -133,23 +134,32 @@ ntfClientHandshake c (k, pk) keyHash ntfVRange = do
     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
+          pubKey <- C.verifyX509 serverKey signedKey
+          (,(getServerCerts c, signedKey)) <$> (C.x509ToPublic (pubKey, []) >>= C.pubKey)
         sendHandshake th $ NtfClientHandshake {ntfVersion = v, keyHash, authPubKey = Just k}
-        pure $ ntfThHandle th v pk sk_
+        pure $ ntfThHandleClient th v pk 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}) <$> k_
-      v3 = v >= authBatchCmdsNTFVersion
-      params' = params {thVersion = v, thAuth, implySessId = v3, batch = v3}
-   in (th :: THandleNTF c) {params = params'}
+ntfThHandleServer :: forall c. THandleNTF c 'TServer -> VersionNTF -> C.PrivateKeyX25519 -> Maybe C.PublicKeyX25519 -> THandleNTF c 'TServer
+ntfThHandleServer th v pk k_ =
+  let thAuth = (\k -> THAuthServer {clientPeerPubKey = k, serverPrivKey = pk}) <$> k_
+   in ntfThHandle_ th v thAuth
 
-ntfTHandle :: Transport c => c -> THandleNTF c
+ntfThHandleClient :: forall c. THandleNTF c 'TClient -> VersionNTF -> C.PrivateKeyX25519 -> Maybe (C.PublicKeyX25519, (X.CertificateChain, X.SignedExact X.PubKey)) -> THandleNTF c 'TClient
+ntfThHandleClient th v pk ck_ =
+  let thAuth = (\(k, ck) -> THAuthClient {serverPeerPubKey = k, serverCertKey = ck, clientPrivKey = pk}) <$> 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}
diff --git a/src/Simplex/Messaging/Protocol.hs b/src/Simplex/Messaging/Protocol.hs
index 2c593fc6f..31577ccdb 100644
--- a/src/Simplex/Messaging/Protocol.hs
+++ b/src/Simplex/Messaging/Protocol.hs
@@ -1075,7 +1075,7 @@ data CommandError
   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 +1089,10 @@ 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 -> C.KeyPairX25519 -> C.KeyHash -> VersionRange v -> ExceptT TransportError IO (THandle v c 'TClient)
   protocolPing :: ProtoCommand msg
   protocolError :: msg -> Maybe err
 
@@ -1308,7 +1308,7 @@ instance Encoding CommandError where
       _ -> fail "bad command error type"
 
 -- | 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 +1317,7 @@ 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 +1383,7 @@ 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 +1391,7 @@ 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 +1404,11 @@ 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 +1420,10 @@ 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 ->
diff --git a/src/Simplex/Messaging/Server.hs b/src/Simplex/Messaging/Server.hs
index 4535c7bd5..5415ebd65 100644
--- a/src/Simplex/Messaging/Server.hs
+++ b/src/Simplex/Messaging/Server.hs
@@ -409,7 +409,7 @@ smpServer started cfg@ServerConfig {transports, transportConfig = tCfg} = do
                     logError "Unauthorized control port command"
                     hPutStrLn h "AUTH"
 
-runClientTransport :: Transport c => THandleSMP c -> M ()
+runClientTransport :: Transport c => THandleSMP c 'TServer -> M ()
 runClientTransport th@THandle {params = THandleParams {thVersion, sessionId}} = do
   q <- asks $ tbqSize . config
   ts <- liftIO getSystemTime
@@ -457,7 +457,7 @@ 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
@@ -478,7 +478,7 @@ receive th@THandle {params = THandleParams {thAuth}} Client {rcvQ, sndQ, rcvActi
               VRFailed -> Left (corrId, queueId, 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
@@ -493,7 +493,7 @@ 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
@@ -514,7 +514,7 @@ 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
@@ -536,7 +536,7 @@ verifyTransmission auth_ tAuth authorized queueId cmd =
       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
@@ -548,12 +548,12 @@ 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
diff --git a/src/Simplex/Messaging/Transport.hs b/src/Simplex/Messaging/Transport.hs
index 6898af15d..6d4ccc83b 100644
--- a/src/Simplex/Messaging/Transport.hs
+++ b/src/Simplex/Messaging/Transport.hs
@@ -12,6 +12,7 @@
 {-# LANGUAGE PatternSynonyms #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE TupleSections #-}
 {-# LANGUAGE TypeApplications #-}
 
 -- |
@@ -311,20 +312,20 @@ 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,
@@ -333,10 +334,18 @@ 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 only in the client to combine with per-queue key
+      serverCertKey :: (X.CertificateChain, X.SignedExact X.PubKey), -- the key here is clientPrivKey signed with server certificate
+      clientPrivKey :: C.PrivateKeyX25519 -- used to combine with peer's per-queue key (currently only in the server)
+    } ->
+    THandleAuth 'TClient
+  THAuthServer ::
+    { clientPeerPubKey :: C.PublicKeyX25519, -- used only in the client to combine with per-queue key
+      serverPrivKey :: C.PrivateKeyX25519 -- used to combine with peer's per-queue key (currently only in the server)
+    } ->
+    THandleAuth 'TServer
 
 -- | TLS-unique channel binding
 type SessionId = ByteString
@@ -438,13 +447,13 @@ 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
@@ -454,7 +463,7 @@ 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
@@ -465,13 +474,13 @@ 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 :: forall c. Transport c => c -> C.KeyPairX25519 -> C.KeyHash -> VersionRangeSMP -> ExceptT TransportError IO (THandleSMP c 'TClient)
 smpClientHandshake c (k, pk) keyHash@(C.KeyHash kh) smpVRange = do
   let th@THandle {params = THandleParams {sessionId}} = smpTHandle c
   ServerHandshake {sessionId = sessId, smpVersionRange, authPubKey} <- getHandshake th
@@ -479,33 +488,42 @@ smpClientHandshake c (k, pk) keyHash@(C.KeyHash kh) smpVRange = do
     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
+            (,certKey) <$> (C.x509ToPublic (pubKey, []) >>= C.pubKey)
         sendHandshake th $ ClientHandshake {smpVersion = v, keyHash, authPubKey = Just k}
-        pure $ smpThHandle th v pk sk_
+        pure $ smpThHandleClient th v pk 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}) <$> k_
-      params' = params {thVersion = v, thAuth, implySessId = v >= authCmdsSMPVersion}
-   in (th :: THandleSMP c) {params = params'}
+smpThHandleServer :: forall c. THandleSMP c 'TServer -> VersionSMP -> C.PrivateKeyX25519 -> Maybe C.PublicKeyX25519 -> THandleSMP c 'TServer
+smpThHandleServer th v pk k_ =
+  let thAuth = (\k -> THAuthServer {clientPeerPubKey = k, serverPrivKey = pk}) <$> k_
+   in smpThHandle_ th v thAuth
 
-sendHandshake :: (Transport c, Encoding smp) => THandle v c -> smp -> ExceptT TransportError IO ()
+smpThHandleClient :: forall c. THandleSMP c 'TClient -> VersionSMP -> 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, clientPrivKey = 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}
diff --git a/tests/CoreTests/BatchingTests.hs b/tests/CoreTests/BatchingTests.hs
index 996d2fed1..c349096dc 100644
--- a/tests/CoreTests/BatchingTests.hs
+++ b/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
@@ -314,7 +319,7 @@ randomSEND_ a v sessId len = do
       TransmissionForAuth {tForAuth, tToSend} = encodeTransmissionForAuth thParams (corrId, sId, Cmd SSender $ SEND noMsgFlags msg)
   pure $ (,tToSend) <$> authTransmission thAuth_ (Just spKey) corrId tForAuth
 
-testTHandleParams :: VersionSMP -> ByteString -> THandleParams SMPVersion
+testTHandleParams :: VersionSMP -> ByteString -> THandleParams SMPVersion 'TClient
 testTHandleParams v sessionId =
   THandleParams
     { sessionId,
@@ -325,11 +330,17 @@ 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}
+    (_, clientPrivKey) <- atomically $ C.generateKeyPair @'C.X25519 g
+    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, clientPrivKey}
   _ -> pure Nothing
 
 randomSENDCmd :: ProtocolClient SMPVersion ErrorType BrokerMsg -> Int -> IO (PCTransmission ErrorType BrokerMsg)
diff --git a/tests/NtfClient.hs b/tests/NtfClient.hs
index 26981628f..d47722944 100644
--- a/tests/NtfClient.hs
+++ b/tests/NtfClient.hs
@@ -70,7 +70,7 @@ 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
@@ -139,7 +139,7 @@ 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 +150,7 @@ 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 +159,7 @@ 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
diff --git a/tests/NtfServerTests.hs b/tests/NtfServerTests.hs
index e7e2018c2..e5f096eef 100644
--- a/tests/NtfServerTests.hs
+++ b/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
 
@@ -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)
diff --git a/tests/SMPClient.hs b/tests/SMPClient.hs
index 3e5e9d2ce..9023574d8 100644
--- a/tests/SMPClient.hs
+++ b/tests/SMPClient.hs
@@ -67,10 +67,10 @@ 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
@@ -150,16 +150,16 @@ 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 +171,7 @@ 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 +180,33 @@ 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"
 
diff --git a/tests/ServerTests.hs b/tests/ServerTests.hs
index 09cf975c1..b4c40cd99 100644
--- a/tests/ServerTests.hs
+++ b/tests/ServerTests.hs
@@ -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),
@@ -770,7 +770,7 @@ testTiming (ATransport t) =
       ]
     timeRepeat n = fmap fst . timeItT . forM_ (replicate n ()) . const
     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 -> THandleSMP c -> (C.AuthAlg, C.AuthAlg, Int) -> Expectation
+    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