From 886e5acc762b879b606773b511ff92345aef14c6 Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Wed, 16 Jan 2019 15:13:07 +0000 Subject: [PATCH] Store rejected remote invite events as outliers Currently they're stored as non-outliers even though the server isn't in the room, which can be problematic in places where the code assumes it has the state for all non outlier events. In particular, there is an edge case where persisting the leave event triggers a state resolution, which requires looking up the room version from state. Since the server doesn't have the state, this causes an exception to be thrown. --- synapse/federation/federation_client.py | 10 ++++-- synapse/handlers/federation.py | 44 +++++++------------------ synapse/storage/roommember.py | 5 +-- 3 files changed, 21 insertions(+), 38 deletions(-) diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py index d05ed91d64..8fa726759e 100644 --- a/synapse/federation/federation_client.py +++ b/synapse/federation/federation_client.py @@ -32,7 +32,6 @@ from synapse.api.errors import ( HttpResponseException, SynapseError, ) -from synapse.events import builder from synapse.federation.federation_base import FederationBase, event_from_pdu_json from synapse.util import logcontext, unwrapFirstError from synapse.util.caches.expiringcache import ExpiringCache @@ -66,6 +65,8 @@ class FederationClient(FederationBase): self.state = hs.get_state_handler() self.transport_layer = hs.get_federation_transport_client() + self.event_builder_factory = hs.get_event_builder_factory() + self._get_pdu_cache = ExpiringCache( cache_name="get_pdu_cache", clock=self._clock, @@ -571,7 +572,12 @@ class FederationClient(FederationBase): if "prev_state" not in pdu_dict: pdu_dict["prev_state"] = [] - ev = builder.EventBuilder(pdu_dict) + # Strip off the fields that we want to clobber. + pdu_dict.pop("origin", None) + pdu_dict.pop("origin_server_ts", None) + pdu_dict.pop("unsigned", None) + + ev = self.event_builder_factory.new(pdu_dict) defer.returnValue( (destination, ev) diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py index a3bb864bb2..70be87cd3d 100644 --- a/synapse/handlers/federation.py +++ b/synapse/handlers/federation.py @@ -43,10 +43,7 @@ from synapse.api.errors import ( StoreError, SynapseError, ) -from synapse.crypto.event_signing import ( - add_hashes_and_signatures, - compute_event_signature, -) +from synapse.crypto.event_signing import compute_event_signature from synapse.events.validator import EventValidator from synapse.replication.http.federation import ( ReplicationCleanRoomRestServlet, @@ -58,7 +55,6 @@ from synapse.types import UserID, get_domain_from_id from synapse.util import logcontext, unwrapFirstError from synapse.util.async_helpers import Linearizer from synapse.util.distributor import user_joined_room -from synapse.util.frozenutils import unfreeze from synapse.util.logutils import log_function from synapse.util.retryutils import NotRetryingDestination from synapse.visibility import filter_events_for_server @@ -1083,7 +1079,9 @@ class FederationHandler(BaseHandler): handled_events = set() try: - event = self._sign_event(event) + self._sign_event(event) + event.internal_metadata.outlier = False + # Try the host we successfully got a response to /make_join/ # request first. try: @@ -1289,13 +1287,7 @@ class FederationHandler(BaseHandler): event.internal_metadata.outlier = True event.internal_metadata.invite_from_remote = True - event.signatures.update( - compute_event_signature( - event, - self.hs.hostname, - self.hs.config.signing_key[0] - ) - ) + self._sign_event(event) context = yield self.state_handler.compute_event_context(event) yield self.persist_events_and_notify([(event, context)]) @@ -1313,7 +1305,7 @@ class FederationHandler(BaseHandler): # Mark as outlier as we don't have any state for this event; we're not # even in the room. event.internal_metadata.outlier = True - event = self._sign_event(event) + self._sign_event(event) # Try the host that we succesfully called /make_leave/ on first for # the /send_leave/ request. @@ -1358,26 +1350,14 @@ class FederationHandler(BaseHandler): defer.returnValue((origin, event)) def _sign_event(self, event): - event.internal_metadata.outlier = False - - builder = self.event_builder_factory.new( - unfreeze(event.get_pdu_json()) + event.signatures.update( + compute_event_signature( + event, + self.hs.hostname, + self.hs.config.signing_key[0] + ) ) - builder.event_id = self.event_builder_factory.create_event_id() - builder.origin = self.hs.hostname - - if not hasattr(event, "signatures"): - builder.signatures = {} - - add_hashes_and_signatures( - builder, - self.hs.hostname, - self.hs.config.signing_key[0], - ) - - return builder.build() - @defer.inlineCallbacks @log_function def on_make_leave_request(self, room_id, user_id): diff --git a/synapse/storage/roommember.py b/synapse/storage/roommember.py index 0707f9a86a..c7488f4259 100644 --- a/synapse/storage/roommember.py +++ b/synapse/storage/roommember.py @@ -591,10 +591,7 @@ class RoomMemberStore(RoomMemberWorkerStore): # i.e., its something that has just happened. # The only current event that can also be an outlier is if its an # invite that has come in across federation. - is_new_state = not backfilled and ( - not event.internal_metadata.is_outlier() - or event.internal_metadata.is_invite_from_remote() - ) + is_new_state = not backfilled is_mine = self.hs.is_mine_id(event.state_key) if is_new_state and is_mine: if event.membership == Membership.INVITE: