diff options
| -rw-r--r-- | changelog.d/6854.misc | 1 | ||||
| -rw-r--r-- | synapse/federation/federation_client.py | 60 | ||||
| -rw-r--r-- | synapse/handlers/federation.py | 3 |
3 files changed, 34 insertions, 30 deletions
diff --git a/changelog.d/6854.misc b/changelog.d/6854.misc new file mode 100644 index 0000000000..08aa80bcd9 --- /dev/null +++ b/changelog.d/6854.misc @@ -0,0 +1 @@ +Refactoring work in preparation for changing the event redaction algorithm. diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py index 110e42b9ed..5fb4bd414c 100644 --- a/synapse/federation/federation_client.py +++ b/synapse/federation/federation_client.py @@ -516,7 +516,7 @@ class FederationClient(FederationBase): ) async def send_join( - self, destinations: Iterable[str], pdu: EventBase, event_format_version: int + self, destinations: Iterable[str], pdu: EventBase, room_version: RoomVersion ) -> Dict[str, Any]: """Sends a join event to one of a list of homeservers. @@ -527,7 +527,8 @@ class FederationClient(FederationBase): destinations: Candidate homeservers which are probably participating in the room. pdu: event to be sent - event_format_version: The event format version + room_version: the version of the room (according to the server that + did the make_join) Returns: a dict with members ``origin`` (a string @@ -540,58 +541,51 @@ class FederationClient(FederationBase): RuntimeError: if no servers were reachable. """ - def check_authchain_validity(signed_auth_chain): - for e in signed_auth_chain: - if e.type == EventTypes.Create: - create_event = e - break - else: - raise InvalidResponseError("no %s in auth chain" % (EventTypes.Create,)) - - # the room version should be sane. - room_version = create_event.content.get("room_version", "1") - if room_version not in KNOWN_ROOM_VERSIONS: - # This shouldn't be possible, because the remote server should have - # rejected the join attempt during make_join. - raise InvalidResponseError( - "room appears to have unsupported version %s" % (room_version,) - ) - async def send_request(destination) -> Dict[str, Any]: content = await self._do_send_join(destination, pdu) logger.debug("Got content: %s", content) state = [ - event_from_pdu_json(p, event_format_version, outlier=True) + event_from_pdu_json(p, room_version.event_format, outlier=True) for p in content.get("state", []) ] auth_chain = [ - event_from_pdu_json(p, event_format_version, outlier=True) + event_from_pdu_json(p, room_version.event_format, outlier=True) for p in content.get("auth_chain", []) ] pdus = {p.event_id: p for p in itertools.chain(state, auth_chain)} - room_version = None + create_event = None for e in state: if (e.type, e.state_key) == (EventTypes.Create, ""): - room_version = e.content.get( - "room_version", RoomVersions.V1.identifier - ) + create_event = e break - if room_version is None: + if create_event is None: # If the state doesn't have a create event then the room is # invalid, and it would fail auth checks anyway. raise SynapseError(400, "No create event in state") + # the room version should be sane. + create_room_version = create_event.content.get( + "room_version", RoomVersions.V1.identifier + ) + if create_room_version != room_version.identifier: + # either the server that fulfilled the make_join, or the server that is + # handling the send_join, is lying. + raise InvalidResponseError( + "Unexpected room version %s in create event" + % (create_room_version,) + ) + valid_pdus = await self._check_sigs_and_hash_and_fetch( destination, list(pdus.values()), outlier=True, - room_version=room_version, + room_version=room_version.identifier, ) valid_pdus_map = {p.event_id: p for p in valid_pdus} @@ -615,7 +609,17 @@ class FederationClient(FederationBase): for s in signed_state: s.internal_metadata = copy.deepcopy(s.internal_metadata) - check_authchain_validity(signed_auth) + # double-check that the same create event has ended up in the auth chain + auth_chain_create_events = [ + e.event_id + for e in signed_auth + if (e.type, e.state_key) == (EventTypes.Create, "") + ] + if auth_chain_create_events != [create_event.event_id]: + raise InvalidResponseError( + "Unexpected create event(s) in auth chain" + % (auth_chain_create_events,) + ) return { "state": signed_state, diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py index ef3cc264b7..10e8b6ea4c 100644 --- a/synapse/handlers/federation.py +++ b/synapse/handlers/federation.py @@ -1305,9 +1305,8 @@ class FederationHandler(BaseHandler): except ValueError: pass - event_format_version = room_version_obj.event_format ret = await self.federation_client.send_join( - target_hosts, event, event_format_version + target_hosts, event, room_version_obj ) origin = ret["origin"] |