From 26305788fe23448d65d0cd0358df547e816574f2 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Fri, 18 May 2018 11:18:39 +0100 Subject: [PATCH] Make sure we reject attempts to invite the notices user --- synapse/handlers/federation.py | 8 ++++++++ synapse/handlers/room_member.py | 7 +++++++ synapse/server_notices/server_notices_manager.py | 5 +++++ 3 files changed, 20 insertions(+) diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py index f39233d84..ba3ede802 100644 --- a/synapse/handlers/federation.py +++ b/synapse/handlers/federation.py @@ -81,6 +81,7 @@ class FederationHandler(BaseHandler): self.pusher_pool = hs.get_pusherpool() self.spam_checker = hs.get_spam_checker() self.event_creation_handler = hs.get_event_creation_handler() + self._server_notices_mxid = hs.config.server_notices_mxid # When joining a room we need to queue any events for that room up self.room_queues = {} @@ -1180,6 +1181,13 @@ class FederationHandler(BaseHandler): if not self.is_mine_id(event.state_key): raise SynapseError(400, "The invite event must be for this server") + # block any attempts to invite the server notices mxid + if event.state_key == self._server_notices_mxid: + raise SynapseError( + http_client.FORBIDDEN, + "Cannot invite this user", + ) + event.internal_metadata.outlier = True event.internal_metadata.invite_from_remote = True diff --git a/synapse/handlers/room_member.py b/synapse/handlers/room_member.py index 9b99f0f9d..5263f09aa 100644 --- a/synapse/handlers/room_member.py +++ b/synapse/handlers/room_member.py @@ -309,6 +309,13 @@ class RoomMemberHandler(object): ) if effective_membership_state == Membership.INVITE: + # block any attempts to invite the server notices mxid + if target.to_string() == self._server_notices_mxid: + raise SynapseError( + http_client.FORBIDDEN, + "Cannot invite this user", + ) + block_invite = False if (self._server_notices_mxid is not None and diff --git a/synapse/server_notices/server_notices_manager.py b/synapse/server_notices/server_notices_manager.py index 0d48aeb95..15086600e 100644 --- a/synapse/server_notices/server_notices_manager.py +++ b/synapse/server_notices/server_notices_manager.py @@ -78,6 +78,11 @@ class ServerNoticesManager(object): ) system_mxid = self._config.server_notices_mxid for room in rooms: + # it's worth noting that there is an asymmetry here in that we + # expect the user to be invited or joined, but the system user must + # be joined. This is kinda deliberate, in that if somebody somehow + # manages to invite the system user to a room, that doesn't make it + # the server notices room. user_ids = yield self._store.get_users_in_room(room.room_id) if system_mxid in user_ids: # we found a room which our user shares with the system notice