diff options
Diffstat (limited to 'synapse/visibility.py')
| -rw-r--r-- | synapse/visibility.py | 29 |
1 files changed, 26 insertions, 3 deletions
diff --git a/synapse/visibility.py b/synapse/visibility.py index 40a9c5b53f..b443857571 100644 --- a/synapse/visibility.py +++ b/synapse/visibility.py @@ -563,7 +563,8 @@ def get_effective_room_visibility_from_state(state: StateMap[EventBase]) -> str: async def filter_events_for_server( storage: StorageControllers, - server_name: str, + target_server_name: str, + local_server_name: str, events: List[EventBase], redact: bool = True, check_history_visibility_only: bool = False, @@ -603,7 +604,7 @@ async def filter_events_for_server( # if the server is either in the room or has been invited # into the room. for ev in memberships.values(): - assert get_domain_from_id(ev.state_key) == server_name + assert get_domain_from_id(ev.state_key) == target_server_name memtype = ev.membership if memtype == Membership.JOIN: @@ -622,6 +623,24 @@ async def filter_events_for_server( # to no users having been erased. erased_senders = {} + # Filter out non-local events when we are in the middle of a partial join, since our servers + # list can be out of date and we could leak events to servers not in the room anymore. + # This can also be true for local events but we consider it to be an acceptable risk. + + # We do this check as a first step and before retrieving membership events because + # otherwise a room could be fully joined after we retrieve those, which would then bypass + # this check but would base the filtering on an outdated view of the membership events. + + partial_state_invisible_events = set() + if not check_history_visibility_only: + for e in events: + sender_domain = get_domain_from_id(e.sender) + if ( + sender_domain != local_server_name + and await storage.main.is_partial_state_room(e.room_id) + ): + partial_state_invisible_events.add(e) + # Let's check to see if all the events have a history visibility # of "shared" or "world_readable". If that's the case then we don't # need to check membership (as we know the server is in the room). @@ -636,7 +655,7 @@ async def filter_events_for_server( if event_to_history_vis[e.event_id] not in (HistoryVisibility.SHARED, HistoryVisibility.WORLD_READABLE) ], - server_name, + target_server_name, ) to_return = [] @@ -645,6 +664,10 @@ async def filter_events_for_server( visible = check_event_is_visible( event_to_history_vis[e.event_id], event_to_memberships.get(e.event_id, {}) ) + + if e in partial_state_invisible_events: + visible = False + if visible and not erased: to_return.append(e) elif redact: |