Merge branch 'erikj/fixup_rejecting_invites' of github.com:matrix-org/synapse into erikj/require_format_version

changelog.d/4405.bugfix

@@ -0,0 +1 @@
+Fix bug when rejecting remote invites

synapse/events/__init__.py

@@ -42,8 +42,12 @@ class _EventInternalMetadata(object):
     def is_outlier(self):
         return getattr(self, "outlier", False)
 
-    def is_invite_from_remote(self):
+    def is_new_remote_event(self):
-        return getattr(self, "invite_from_remote", False)
+        """Whether this is a new remote event, like an invite or an invite
+        rejection. This is needed as those events are marked as outliers, but
+        they still need to be processed.
+        """
+        return getattr(self, "new_remote_event", False)
 
     def get_send_on_behalf_of(self):
         """Whether this server should send the event on behalf of another server.

synapse/federation/federation_client.py

@@ -37,7 +37,8 @@ from synapse.api.errors import (
     HttpResponseException,
     SynapseError,
 )
-from synapse.events import builder, room_version_to_event_format
+from synapse.events import room_version_to_event_format
+from synapse.crypto.event_signing import add_hashes_and_signatures
 from synapse.federation.federation_base import FederationBase, event_from_pdu_json
 from synapse.util import logcontext, unwrapFirstError
 from synapse.util.caches.expiringcache import ExpiringCache
@@ -71,6 +72,8 @@ 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,
@@ -594,7 +597,18 @@ 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)
+
+            builder = self.event_builder_factory.new(pdu_dict)
+            add_hashes_and_signatures(
+                builder,
+                self.hs.hostname,
+                self.hs.config.signing_key[0]
+            )
+            ev = builder.build()
 
             defer.returnValue(
                 (destination, ev, event_format)

synapse/handlers/federation.py

@@ -44,10 +44,7 @@ from synapse.api.errors import (
     StoreError,
     SynapseError,
 )
-from synapse.crypto.event_signing import (
+from synapse.crypto.event_signing import compute_event_signature
-    add_hashes_and_signatures,
-    compute_event_signature,
-)
 from synapse.events.validator import EventValidator
 from synapse.replication.http.federation import (
     ReplicationCleanRoomRestServlet,
@@ -59,7 +56,6 @@ 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
@@ -1088,7 +1084,8 @@ class FederationHandler(BaseHandler):
         handled_events = set()
 
         try:
-            event = self._sign_event(event)
+            event.internal_metadata.outlier = False
+
             # Try the host we successfully got a response to /make_join/
             # request first.
             try:
@@ -1292,7 +1289,7 @@ class FederationHandler(BaseHandler):
             )
 
         event.internal_metadata.outlier = True
-        event.internal_metadata.invite_from_remote = True
+        event.internal_metadata.new_remote_event = True
 
         event.signatures.update(
             compute_event_signature(
@@ -1318,7 +1315,7 @@ 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)
+        event.internal_metadata.new_remote_event = True
 
         # Try the host that we succesfully called /make_leave/ on first for
         # the /send_leave/ request.
@@ -1362,27 +1359,6 @@ class FederationHandler(BaseHandler):
         assert(event.room_id == room_id)
         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())
-        )
-
-        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):

synapse/storage/roommember.py

@@ -588,12 +588,12 @@ class RoomMemberStore(RoomMemberWorkerStore):
             )
 
             # We update the local_invites table only if the event is "current",
-            # i.e., its something that has just happened.
+            # i.e., its something that has just happened. If the event is an
-            # The only current event that can also be an outlier is if its an
+            # outlier it is only current if its a "new remote event", like a
-            # invite that has come in across federation.
+            # remote invite or a rejection of a remote invite.
             is_new_state = not backfilled and (
                 not event.internal_metadata.is_outlier()
-                or event.internal_metadata.is_invite_from_remote()
+                or event.internal_metadata.is_new_remote_event()
             )
             is_mine = self.hs.is_mine_id(event.state_key)
             if is_new_state and is_mine: