feat(core): expect channel messages with noise tag

core/src/trezor/wire/thp/channel.py

@@ -44,7 +44,8 @@ MAX_PAYLOAD_LEN = const(60000)
 
 class Channel(Context):
     def __init__(self, channel_cache: ChannelCache) -> None:
-        print("channel.__init__")
+        if __debug__:
+            log.debug(__name__, "channel initialization")
         iface = _decode_iface(channel_cache.iface)
         super().__init__(iface, channel_cache.channel_id)
         self.channel_cache = channel_cache
@@ -279,7 +280,9 @@ class Channel(Context):
         self.sessions[session_id].incoming_message.publish(
             MessageWithType(
                 message_type,
-                self.buffer[INIT_DATA_OFFSET + 3 : message_length - CHECKSUM_LENGTH],
+                self.buffer[
+                    INIT_DATA_OFFSET + 3 : message_length - CHECKSUM_LENGTH - TAG_LENGTH
+                ],
             )
         )
 
@@ -287,13 +290,16 @@ class Channel(Context):
         pass
 
     def _handle_channel_message(self, message_length: int, message_type: int) -> None:
-        buf = self.buffer[INIT_DATA_OFFSET + 3 : message_length - CHECKSUM_LENGTH]
+        buf = self.buffer[
+            INIT_DATA_OFFSET + 3 : message_length - CHECKSUM_LENGTH - TAG_LENGTH
+        ]
 
         expected_type = protobuf.type_for_wire(message_type)
         message = message_handler.wrap_protobuf_load(buf, expected_type)
         print("channel._handle_channel_message:", message)
         # TODO handle other messages than CreateNewSession
-        assert isinstance(message, ThpCreateNewSession)
+        if TYPE_CHECKING:
+            assert isinstance(message, ThpCreateNewSession)
         print("channel._handle_channel_message - passphrase:", message.passphrase)
         # await thp_messages.handle_CreateNewSession(message)
         if message.passphrase is not None:
@@ -376,7 +382,7 @@ class Channel(Context):
     # CALLED BY WORKFLOW / SESSION CONTEXT
 
     async def write(self, msg: protobuf.MessageType, session_id: int = 0) -> None:
-        print("channel.write")
+        print("channel.write:" + msg.MESSAGE_NAME)
         noise_payload_len = self._encode_into_buffer(msg, session_id)
         await self.write_and_encrypt(self.buffer[:noise_payload_len])
 
@@ -600,8 +606,12 @@ def is_channel_state_pairing(state: int) -> bool:
 
 
 def _state_to_str(state: int) -> str:
-    names = {v: k for k, v in ChannelState.__dict__.items() if not k.startswith("__")}
-    return names.get(state)
+    name = {
+        v: k for k, v in ChannelState.__dict__.items() if not k.startswith("__")
+    }.get(state)
+    if name is not None:
+        return name
+    return "UNKNOWN_STATE"
 
 
 def printBytes(a):