diff options
Diffstat (limited to 'synapse/handlers/message.py')
| -rw-r--r-- | synapse/handlers/message.py | 28 |
1 files changed, 25 insertions, 3 deletions
diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py index 101a29c6d3..9d2c897341 100644 --- a/synapse/handlers/message.py +++ b/synapse/handlers/message.py @@ -1393,6 +1393,9 @@ class EventCreationHandler: allow_none=True, ) + room_version = await self.store.get_room_version_id(event.room_id) + room_version_obj = KNOWN_ROOM_VERSIONS[room_version] + # we can make some additional checks now if we have the original event. if original_event: if original_event.type == EventTypes.Create: @@ -1404,6 +1407,28 @@ class EventCreationHandler: if original_event.type == EventTypes.ServerACL: raise AuthError(403, "Redacting server ACL events is not permitted") + # Add a little safety stop-gap to prevent people from trying to + # redact MSC2716 related events when they're in a room version + # which does not support it yet. We allow people to use MSC2716 + # events in existing room versions but only from the room + # creator since it does not require any changes to the auth + # rules and in effect, the redaction algorithm . In the + # supported room version, we add the `historical` power level to + # auth the MSC2716 related events and adjust the redaction + # algorthim to keep the `historical` field around (redacting an + # event should only strip fields which don't affect the + # structural protocol level). + is_msc2716_event = ( + original_event.type == EventTypes.MSC2716_INSERTION + or original_event.type == EventTypes.MSC2716_CHUNK + or original_event.type == EventTypes.MSC2716_MARKER + ) + if not room_version_obj.msc2716_historical and is_msc2716_event: + raise AuthError( + 403, + "Redacting MSC2716 events is not supported in this room version", + ) + prev_state_ids = await context.get_prev_state_ids() auth_events_ids = self._event_auth_handler.compute_auth_events( event, prev_state_ids, for_verification=True @@ -1411,9 +1436,6 @@ class EventCreationHandler: auth_events_map = await self.store.get_events(auth_events_ids) auth_events = {(e.type, e.state_key): e for e in auth_events_map.values()} - room_version = await self.store.get_room_version_id(event.room_id) - room_version_obj = KNOWN_ROOM_VERSIONS[room_version] - if event_auth.check_redaction( room_version_obj, event, auth_events=auth_events ): |