diff --git a/synapse/storage/events_worker.py b/synapse/storage/events_worker.py
index 0a0ca58fc4..ebe1429acb 100644
--- a/synapse/storage/events_worker.py
+++ b/synapse/storage/events_worker.py
@@ -21,13 +21,14 @@ from canonicaljson import json
from twisted.internet import defer
-from synapse.api.constants import EventFormatVersions
+from synapse.api.constants import EventFormatVersions, EventTypes
from synapse.api.errors import NotFoundError
from synapse.events import FrozenEvent, event_type_from_format_version # noqa: F401
# these are only included to make the type annotations work
from synapse.events.snapshot import EventContext # noqa: F401
from synapse.events.utils import prune_event
from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.types import get_domain_from_id
from synapse.util.logcontext import (
LoggingContext,
PreserveLoggingContext,
@@ -162,7 +163,6 @@ class EventsWorkerStore(SQLBaseStore):
missing_events = yield self._enqueue_events(
missing_events_ids,
- check_redacted=check_redacted,
allow_rejected=allow_rejected,
)
@@ -174,6 +174,29 @@ class EventsWorkerStore(SQLBaseStore):
if not entry:
continue
+ # Starting in room version v3, some redactions need to be rechecked if we
+ # didn't have the redacted event at the time, so we recheck on read
+ # instead.
+ if not allow_rejected and entry.event.type == EventTypes.Redaction:
+ if entry.event.internal_metadata.need_to_check_redaction():
+ orig = yield self.get_event(
+ entry.event.redacts,
+ allow_none=True,
+ allow_rejected=True,
+ get_prev_content=False,
+ )
+ expected_domain = get_domain_from_id(entry.event.sender)
+ if orig and get_domain_from_id(orig.sender) == expected_domain:
+ # This redaction event is allowed. Mark as not needing a
+ # recheck.
+ entry.event.internal_metadata.recheck_redaction = False
+ else:
+ # We don't have the event that is being redacted, so we
+ # assume that the event isn't authorized for now. (If we
+ # later receive the event, then we will always redact
+ # it anyway, since we have this redaction)
+ continue
+
if allow_rejected or not entry.event.rejected_reason:
if check_redacted and entry.redacted_event:
event = entry.redacted_event
@@ -310,7 +333,7 @@ class EventsWorkerStore(SQLBaseStore):
self.hs.get_reactor().callFromThread(fire, event_list, e)
@defer.inlineCallbacks
- def _enqueue_events(self, events, check_redacted=True, allow_rejected=False):
+ def _enqueue_events(self, events, allow_rejected=False):
"""Fetches events from the database using the _event_fetch_list. This
allows batch and bulk fetching of events - it allows us to fetch events
without having to create a new transaction for each request for events.
@@ -443,6 +466,19 @@ class EventsWorkerStore(SQLBaseStore):
# will serialise this field correctly
redacted_event.unsigned["redacted_because"] = because
+ # Starting in room version v3, some redactions need to be
+ # rechecked if we didn't have the redacted event at the
+ # time, so we recheck on read instead.
+ if because.internal_metadata.need_to_check_redaction():
+ expected_domain = get_domain_from_id(original_ev.sender)
+ if get_domain_from_id(because.sender) == expected_domain:
+ # This redaction event is allowed. Mark as not needing a
+ # recheck.
+ because.internal_metadata.recheck_redaction = False
+ else:
+ # Senders don't match, so the event isn't actually redacted
+ redacted_event = None
+
cache_entry = _EventCacheEntry(
event=original_ev,
redacted_event=redacted_event,
|
