ssl: Avoid sending internal message to client

lib/ssl/src/ssl_trace.erl

@@ -491,7 +491,7 @@ trace_profiles() ->
       fun(M, F, A) -> dbg:ctpl(M, F, A) end,
       [{tls_gen_connection_1_3, [{handle_key_update, 2}]},
        {tls_sender, [{init, 3}, {time_to_rekey, 5},
-                     {send_post_handshake_data, 4}]},
+                     {send_post_handshake_data, 5}]},
        {tls_v1, [{update_traffic_secret, 2}]}]},
      {rle, %% role
       fun(M, F, A) -> dbg:tpl(M, F, A, x) end,

lib/ssl/src/tls_sender.erl

@@ -284,7 +284,7 @@ connection({call, From}, {application_data, Data}, StateData) ->
 connection({call, From}, {post_handshake_data, HSData}, #data{buff = Buff} = StateData) ->
     case Buff of
         undefined ->
-            send_post_handshake_data(HSData, From, connection, StateData);
+            send_post_handshake_data(HSData, From, connection, StateData, [{reply, From, ok}]);
         Async ->
             {next_state, async_wait, StateData#data{buff = Async#async{low = 0}}, [postpone]}
     end;
@@ -328,7 +328,7 @@ connection(internal, {application_packets, From, Data}, StateData) ->
 connection(internal, {post_handshake_data, From, HSData}, #data{buff = Buff} = StateData) ->
      case Buff of
          undefined ->
-             send_post_handshake_data(HSData, From, connection, StateData);
+             send_post_handshake_data(HSData, From, connection, StateData, []);
          Async ->
              {next_state, async_wait, StateData#data{buff = Async#async{low = 0}}, [postpone]}
      end;
@@ -554,13 +554,13 @@ send_application_data(Data, From, StateName,
             KeyUpdate = tls_handshake_1_3:key_update(update_requested),
             case DataSz > KeyUpdateAt of
                 false ->
-                    {keep_state_and_data, [{next_event, internal, {post_handshake_data, From, KeyUpdate}},
+                    {keep_state_and_data, [{next_event, internal, {post_handshake_data, undefined, KeyUpdate}},
                                            {next_event, internal, {application_packets, From, Data}}]};
                 true ->
                     %% Prevent infinite loop of key updates
                     {Chunk, Rest} = split_binary(iolist_to_binary(Data), KeyUpdateAt),
-                    {keep_state_and_data, [{next_event, internal, {post_handshake_data, From, KeyUpdate}},
-                                           {next_event, internal, {application_packets, From, [Chunk]}},
+                    {keep_state_and_data, [{next_event, internal, {post_handshake_data, undefined, KeyUpdate}},
+                                           {next_event, internal, {application_packets, undefined, [Chunk]}},
                                            {next_event, internal, {application_packets, From, [Rest]}}]}
             end;
 	{renegotiate, _} ->
@@ -730,7 +730,7 @@ send_post_handshake_data(Handshake, From, StateName,
                          #data{env = #env{socket = Socket,
                                           negotiated_version = Version,
                                           transport_cb = Transport},
-                               connection_states = ConnStates0} = StateData0) ->
+                               connection_states = ConnStates0} = StateData0, AckAction) ->
     BinHandshake = tls_handshake:encode_handshake(Handshake, Version),
     {Encoded, ConnStates} =
         tls_record:encode_handshake(BinHandshake, Version, ConnStates0),
@@ -745,7 +745,9 @@ send_post_handshake_data(Handshake, From, StateName,
         ok ->
             ssl_logger:debug(LogLevel, outbound, 'record', Encoded),
             StateData = maybe_update_cipher_key(StateData1, Handshake),
-            {next_state, StateName, StateData,  [{reply, From, ok}]};
+            %% AckAction will send sync message if post_handshake_data
+            %% was initiated by peer via the receiver process.
+            {next_state, StateName, StateData,  AckAction};
         {error, Reason} ->
             death_row_shutdown(Reason, StateData1)
     end.

lib/ssl/test/ssl_key_update_SUITE.erl

@@ -43,7 +43,9 @@
          keylog_client_cb/0,
          keylog_client_cb/1,
          keylog_server_cb/0,
-         keylog_server_cb/1
+         keylog_server_cb/1,
+         key_update_unexpected_msg/0,
+         key_update_unexpected_msg/1
         ]).
 
 -include("ssl_test_lib.hrl").
@@ -62,7 +64,8 @@ tls_1_3_tests() ->
      key_update_at_server,
      explicit_key_update,
      keylog_client_cb,
-     keylog_server_cb].
+     keylog_server_cb,
+     key_update_unexpected_msg].
 
 init_per_suite(Config0) ->
     case application:ensure_started(crypto) of
@@ -201,6 +204,25 @@ keylog_server_cb(Config) ->
     end,
     ok = traffic_secret_1_and_2([{client,1}, {client, 2}, {server,1}, {server, 2}]).
 
+
+key_update_unexpected_msg() ->
+    [{doc,"Test that internla sync messages are not sent to socket user"}].
+key_update_unexpected_msg(Config) ->
+    Data = "123456789012345",  %% 15 bytes
+    Server = ssl_test_lib:start_server(erlang,[], Config),
+    Port = ssl_test_lib:inet_port(Server),
+
+    {ok, Socket} = ssl:connect(net_adm:localhost(), Port, [{verify, verify_none}, {key_update_at, 9}]),
+
+    ok = ssl:send(Socket, Data),
+
+    receive
+        {_, ok} = Msg ->
+            ct:fail({unexpected_message, Msg})
+    after 500 ->
+          ok
+    end.
+
 %%--------------------------------------------------------------------
 %% Internal functions  -----------------------------------------------
 %%--------------------------------------------------------------------