diff options
Diffstat (limited to 'synapse/handlers')
| -rw-r--r-- | synapse/handlers/message.py | 54 |
1 files changed, 48 insertions, 6 deletions
diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py index d4c2a6ab7a..22dd4cf5fd 100644 --- a/synapse/handlers/message.py +++ b/synapse/handlers/message.py @@ -1001,13 +1001,52 @@ class EventCreationHandler: ) self.validator.validate_new(event, self.config) + await self._validate_event_relation(event) + logger.debug("Created event %s", event.event_id) + + return event, context + + async def _validate_event_relation(self, event: EventBase) -> None: + """ + Ensure the relation data on a new event is not bogus. + + Args: + event: The event being created. + + Raises: + SynapseError if the event is invalid. + """ + + relation = event.content.get("m.relates_to") + if not relation: + return + + relation_type = relation.get("rel_type") + if not relation_type: + return + + # Ensure the parent is real. + relates_to = relation.get("event_id") + if not relates_to: + return + + parent_event = await self.store.get_event(relates_to, allow_none=True) + if parent_event: + # And in the same room. + if parent_event.room_id != event.room_id: + raise SynapseError(400, "Relations must be in the same room") + + else: + # There must be some reason that the client knows the event exists, + # see if there are existing relations. If so, assume everything is fine. + if not await self.store.event_is_target_of_relation(relates_to): + # Otherwise, the client can't know about the parent event! + raise SynapseError(400, "Can't send relation to unknown event") # If this event is an annotation then we check that that the sender # can't annotate the same way twice (e.g. stops users from liking an # event multiple times). - relation = event.content.get("m.relates_to", {}) - if relation.get("rel_type") == RelationTypes.ANNOTATION: - relates_to = relation["event_id"] + if relation_type == RelationTypes.ANNOTATION: aggregation_key = relation["key"] already_exists = await self.store.has_user_annotated_event( @@ -1016,9 +1055,12 @@ class EventCreationHandler: if already_exists: raise SynapseError(400, "Can't send same reaction twice") - logger.debug("Created event %s", event.event_id) - - return event, context + # Don't attempt to start a thread if the parent event is a relation. + elif relation_type == RelationTypes.THREAD: + if await self.store.event_includes_relation(relates_to): + raise SynapseError( + 400, "Cannot start threads from an event with a relation" + ) @measure_func("handle_new_client_event") async def handle_new_client_event( |