Remove room_version param from check_auth_rules_for_event

Instead, use the `room_version` property of the event we're checking.

The `room_version` was originally added as a parameter somewhere around #4482,
but really it's been redundant since #6875 added a `room_version` field to `EventBase`.

synapse/event_auth.py

@@ -113,7 +113,6 @@ def validate_event_for_room_version(event: "EventBase") -> None:
 
 
 def check_auth_rules_for_event(
-    room_version_obj: RoomVersion,
     event: "EventBase",
     auth_events: Iterable["EventBase"],
 ) -> None:
@@ -132,7 +131,6 @@ def check_auth_rules_for_event(
        a bunch of other tests.
 
     Args:
-        room_version_obj: the version of the room
         event: the event being checked.
         auth_events: the room state to check the events against.
 
@@ -201,7 +199,10 @@ def check_auth_rules_for_event(
             raise AuthError(403, "This room has been marked as unfederatable.")
 
     # 4. If type is m.room.aliases
-    if event.type == EventTypes.Aliases and room_version_obj.special_case_aliases_auth:
+    if (
+        event.type == EventTypes.Aliases
+        and event.room_version.special_case_aliases_auth
+    ):
         # 4a. If event has no state_key, reject
         if not event.is_state():
             raise AuthError(403, "Alias event must be a state event")
@@ -221,7 +222,7 @@ def check_auth_rules_for_event(
 
     # 5. If type is m.room.membership
     if event.type == EventTypes.Member:
-        _is_membership_change_allowed(room_version_obj, event, auth_dict)
+        _is_membership_change_allowed(event.room_version, event, auth_dict)
         logger.debug("Allowing! %s", event)
         return
 
@@ -243,17 +244,17 @@ def check_auth_rules_for_event(
     _can_send_event(event, auth_dict)
 
     if event.type == EventTypes.PowerLevels:
-        _check_power_levels(room_version_obj, event, auth_dict)
+        _check_power_levels(event.room_version, event, auth_dict)
 
     if event.type == EventTypes.Redaction:
-        check_redaction(room_version_obj, event, auth_dict)
+        check_redaction(event.room_version, event, auth_dict)
 
     if (
         event.type == EventTypes.MSC2716_INSERTION
         or event.type == EventTypes.MSC2716_BATCH
         or event.type == EventTypes.MSC2716_MARKER
     ):
-        check_historical(room_version_obj, event, auth_dict)
+        check_historical(event.room_version, event, auth_dict)
 
     logger.debug("Allowing! %s", event)
 

synapse/handlers/event_auth.py

@@ -55,7 +55,7 @@ async def check_auth_rules_from_context(
         """Check an event passes the auth rules at its own auth events"""
         auth_event_ids = event.auth_event_ids()
         auth_events_by_id = await self._store.get_events(auth_event_ids)
-        check_auth_rules_for_event(room_version_obj, event, auth_events_by_id.values())
+        check_auth_rules_for_event(event, auth_events_by_id.values())
 
     def compute_auth_events(
         self,

synapse/handlers/federation_event.py

@@ -1430,9 +1430,6 @@ async def _auth_and_persist_outliers_inner(
             allow_rejected=True,
         )
 
-        room_version = await self._store.get_room_version_id(room_id)
-        room_version_obj = KNOWN_ROOM_VERSIONS[room_version]
-
         def prep(event: EventBase) -> Optional[Tuple[EventBase, EventContext]]:
             with nested_logging_context(suffix=event.event_id):
                 auth = []
@@ -1456,7 +1453,7 @@ def prep(event: EventBase) -> Optional[Tuple[EventBase, EventContext]]:
                 context = EventContext.for_outlier(self._storage_controllers)
                 try:
                     validate_event_for_room_version(event)
-                    check_auth_rules_for_event(room_version_obj, event, auth)
+                    check_auth_rules_for_event(event, auth)
                 except AuthError as e:
                     logger.warning("Rejecting %r because %s", event, e)
                     context.rejected = RejectedReason.AUTH_ERROR
@@ -1499,9 +1496,6 @@ async def _check_event_auth(
         assert not event.internal_metadata.outlier
 
         # first of all, check that the event itself is valid.
-        room_version = await self._store.get_room_version_id(event.room_id)
-        room_version_obj = KNOWN_ROOM_VERSIONS[room_version]
-
         try:
             validate_event_for_room_version(event)
         except AuthError as e:
@@ -1521,7 +1515,7 @@ async def _check_event_auth(
 
         # ... and check that the event passes auth at those auth events.
         try:
-            check_auth_rules_for_event(room_version_obj, event, claimed_auth_events)
+            check_auth_rules_for_event(event, claimed_auth_events)
         except AuthError as e:
             logger.warning(
                 "While checking auth of %r against auth_events: %s", event, e
@@ -1569,9 +1563,7 @@ async def _check_event_auth(
             auth_events_for_auth = calculated_auth_event_map
 
         try:
-            check_auth_rules_for_event(
-                room_version_obj, event, auth_events_for_auth.values()
-            )
+            check_auth_rules_for_event(event, auth_events_for_auth.values())
         except AuthError as e:
             logger.warning("Failed auth resolution for %r because %s", event, e)
             context.rejected = RejectedReason.AUTH_ERROR
@@ -1671,7 +1663,7 @@ async def _check_for_soft_fail(
         )
 
         try:
-            check_auth_rules_for_event(room_version_obj, event, current_auth_events)
+            check_auth_rules_for_event(event, current_auth_events)
         except AuthError as e:
             logger.warning(
                 "Soft-failing %r (from %s) because %s",

synapse/state/v1.py

@@ -30,7 +30,7 @@
 from synapse import event_auth
 from synapse.api.constants import EventTypes
 from synapse.api.errors import AuthError
-from synapse.api.room_versions import RoomVersion, RoomVersions
+from synapse.api.room_versions import RoomVersion
 from synapse.events import EventBase
 from synapse.types import MutableStateMap, StateMap
 
@@ -331,7 +331,6 @@ def _resolve_auth_events(
         try:
             # The signatures have already been checked at this point
             event_auth.check_auth_rules_for_event(
-                RoomVersions.V1,
                 event,
                 auth_events.values(),
             )
@@ -349,7 +348,6 @@ def _resolve_normal_events(
         try:
             # The signatures have already been checked at this point
             event_auth.check_auth_rules_for_event(
-                RoomVersions.V1,
                 event,
                 auth_events.values(),
             )

synapse/state/v2.py

@@ -574,7 +574,6 @@ async def _iterative_auth_checks(
 
         try:
             event_auth.check_auth_rules_for_event(
-                room_version,
                 event,
                 auth_events.values(),
             )