mirrors/synapse
1
0
Fork 0
mirror of https://github.com/element-hq/synapse.git synced 2024-12-14 11:57:44 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 3

Handle outliers in /federation/v1/event (#12332)

Browse source 
The intention here is to avoid doing state lookups for outliers in
`/_matrix/federation/v1/event`. Unfortunately that's expanded into something of
a rewrite of `filter_events_for_server`, which ended up trying to do that
operation in a couple of places.
This commit is contained in:
Richard van der Hoff 2022-03-31 18:39:34 +01:00 committed by GitHub
parent 11df4ec6c2
commit 6927d87254
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
3 changed files with 176 additions and 100 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

1
changelog.d/12332.misc Normal file
View file

@ -0,0 +1 @@
Avoid trying to calculate the state at outlier events.

192
synapse/visibility.py
View file

@ -1,4 +1,5 @@
# Copyright 2014 - 2016 OpenMarket Ltd
# Copyright (C) The Matrix.org Foundation C.I.C. 2022
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
@ -12,7 +13,9 @@
# See the License for the specific language governing permissions and
# limitations under the License.
import logging
from typing import Dict, FrozenSet, List, Optional
from typing import Collection, Dict, FrozenSet, List, Optional, Tuple
from typing_extensions import Final
from synapse.api.constants import EventTypes, HistoryVisibility, Membership
from synapse.events import EventBase
@ -40,6 +43,8 @@ MEMBERSHIP_PRIORITY = (
Membership.BAN,
)
_HISTORY_VIS_KEY: Final[Tuple[str, str]] = (EventTypes.RoomHistoryVisibility, "")
async def filter_events_for_client(
storage: Storage,
@ -74,7 +79,7 @@ async def filter_events_for_client(
# to clients.
events = [e for e in events if not e.internal_metadata.is_soft_failed()]
types = ((EventTypes.RoomHistoryVisibility, ""), (EventTypes.Member, user_id))
types = (_HISTORY_VIS_KEY, (EventTypes.Member, user_id))
# we exclude outliers at this point, and then handle them separately later
event_id_to_state = await storage.state.get_state_for_events(
@ -157,7 +162,7 @@ async def filter_events_for_client(
state = event_id_to_state[event.event_id]
# get the room_visibility at the time of the event.
visibility_event = state.get((EventTypes.RoomHistoryVisibility, ""), None)
visibility_event = state.get(_HISTORY_VIS_KEY, None)
if visibility_event:
visibility = visibility_event.content.get(
"history_visibility", HistoryVisibility.SHARED
@ -293,27 +298,18 @@ async def filter_events_for_server(
return True
return False
def check_event_is_visible(event: EventBase, state: StateMap[EventBase]) -> bool:
history = state.get((EventTypes.RoomHistoryVisibility, ""), None)
if history:
visibility = history.content.get(
"history_visibility", HistoryVisibility.SHARED
)
if visibility in [HistoryVisibility.INVITED, HistoryVisibility.JOINED]:
# We now loop through all state events looking for
def check_event_is_visible(
visibility: str, memberships: StateMap[EventBase]
) -> bool:
if visibility not in (HistoryVisibility.INVITED, HistoryVisibility.JOINED):
return True
# We now loop through all membership events looking for
# membership states for the requesting server to determine
# if the server is either in the room or has been invited
# into the room.
for ev in state.values():
if ev.type != EventTypes.Member:
continue
try:
domain = get_domain_from_id(ev.state_key)
except Exception:
continue
if domain != server_name:
continue
for ev in memberships.values():
assert get_domain_from_id(ev.state_key) == server_name
memtype = ev.membership
if memtype == Membership.JOIN:
@ -321,40 +317,10 @@ async def filter_events_for_server(
elif memtype == Membership.INVITE:
if visibility == HistoryVisibility.INVITED:
return True
else:
# server has no users in the room: redact
return False
return True
# Lets check to see if all the events have a history visibility
# of "shared" or "world_readable". If that's the case then we don't
# need to check membership (as we know the server is in the room).
event_to_state_ids = await storage.state.get_state_ids_for_events(
frozenset(e.event_id for e in events),
state_filter=StateFilter.from_types(
types=((EventTypes.RoomHistoryVisibility, ""),)
),
)
visibility_ids = set()
for sids in event_to_state_ids.values():
hist = sids.get((EventTypes.RoomHistoryVisibility, ""))
if hist:
visibility_ids.add(hist)
# If we failed to find any history visibility events then the default
# is "shared" visibility.
if not visibility_ids:
all_open = True
else:
event_map = await storage.main.get_events(visibility_ids)
all_open = all(
e.content.get("history_visibility")
in (None, HistoryVisibility.SHARED, HistoryVisibility.WORLD_READABLE)
for e in event_map.values()
)
if not check_history_visibility_only:
erased_senders = await storage.main.are_users_erased(e.sender for e in events)
else:
@ -362,34 +328,100 @@ async def filter_events_for_server(
# to no users having been erased.
erased_senders = {}
if all_open:
# all the history_visibility state affecting these events is open, so
# we don't need to filter by membership state. We *do* need to check
# for user erasure, though.
if erased_senders:
# Let's check to see if all the events have a history visibility
# of "shared" or "world_readable". If that's the case then we don't
# need to check membership (as we know the server is in the room).
event_to_history_vis = await _event_to_history_vis(storage, events)
# for any with restricted vis, we also need the memberships
event_to_memberships = await _event_to_memberships(
storage,
[
e
for e in events
if event_to_history_vis[e.event_id]
not in (HistoryVisibility.SHARED, HistoryVisibility.WORLD_READABLE)
],
server_name,
)
to_return = []
for e in events:
if not is_sender_erased(e, erased_senders):
erased = is_sender_erased(e, erased_senders)
visible = check_event_is_visible(
event_to_history_vis[e.event_id], event_to_memberships.get(e.event_id, {})
)
if visible and not erased:
to_return.append(e)
elif redact:
to_return.append(prune_event(e))
return to_return
# If there are no erased users then we can just return the given list
# of events without having to copy it.
return events
# Ok, so we're dealing with events that have non-trivial visibility
# rules, so we need to also get the memberships of the room.
async def _event_to_history_vis(
storage: Storage, events: Collection[EventBase]
) -> Dict[str, str]:
"""Get the history visibility at each of the given events
# first, for each event we're wanting to return, get the event_ids
# of the history vis and membership state at those events.
Returns a map from event id to history_visibility setting
"""
# outliers get special treatment here. We don't have the state at that point in the
# room (and attempting to look it up will raise an exception), so all we can really
# do is assume that the requesting server is allowed to see the event. That's
# equivalent to there not being a history_visibility event, so we just exclude
# any outliers from the query.
event_to_state_ids = await storage.state.get_state_ids_for_events(
frozenset(e.event_id for e in events if not e.internal_metadata.is_outlier()),
state_filter=StateFilter.from_types(types=(_HISTORY_VIS_KEY,)),
)
visibility_ids = {
vis_event_id
for vis_event_id in (
state_ids.get(_HISTORY_VIS_KEY) for state_ids in event_to_state_ids.values()
)
if vis_event_id
}
vis_events = await storage.main.get_events(visibility_ids)
result: Dict[str, str] = {}
for event in events:
vis = HistoryVisibility.SHARED
state_ids = event_to_state_ids.get(event.event_id)
# if we didn't find any state for this event, it's an outlier, and we assume
# it's open
visibility_id = None
if state_ids:
visibility_id = state_ids.get(_HISTORY_VIS_KEY)
if visibility_id:
vis_event = vis_events[visibility_id]
vis = vis_event.content.get("history_visibility", HistoryVisibility.SHARED)
assert isinstance(vis, str)
result[event.event_id] = vis
return result
async def _event_to_memberships(
storage: Storage, events: Collection[EventBase], server_name: str
) -> Dict[str, StateMap[EventBase]]:
"""Get the remote membership list at each of the given events
Returns a map from event id to state map, which will contain only membership events
for the given server.
"""
if not events:
return {}
# for each event, get the event_ids of the membership state at those events.
event_to_state_ids = await storage.state.get_state_ids_for_events(
frozenset(e.event_id for e in events),
state_filter=StateFilter.from_types(
types=((EventTypes.RoomHistoryVisibility, ""), (EventTypes.Member, None))
),
state_filter=StateFilter.from_types(types=((EventTypes.Member, None),)),
)
# We only want to pull out member events that correspond to the
@ -405,10 +437,7 @@ async def filter_events_for_server(
for key, event_id in key_to_eid.items()
}
def include(typ, state_key):
if typ != EventTypes.Member:
return True
def include(state_key: str) -> bool:
# we avoid using get_domain_from_id here for efficiency.
idx = state_key.find(":")
if idx == -1:
@ -416,10 +445,14 @@ async def filter_events_for_server(
return state_key[idx + 1 :] == server_name
event_map = await storage.main.get_events(
[e_id for e_id, key in event_id_to_state_key.items() if include(key[0], key[1])]
[
e_id
for e_id, (_, state_key) in event_id_to_state_key.items()
if include(state_key)
]
)
event_to_state = {
return {
e_id: {
key: event_map[inner_e_id]
for key, inner_e_id in key_to_eid.items()
@ -427,14 +460,3 @@ async def filter_events_for_server(
}
for e_id, key_to_eid in event_to_state_ids.items()
}
to_return = []
for e in events:
erased = is_sender_erased(e, erased_senders)
visible = check_event_is_visible(e, event_to_state[e.event_id])
if visible and not erased:
to_return.append(e)
elif redact:
to_return.append(prune_event(e))
return to_return

53
tests/test_visibility.py
View file

@ -17,6 +17,7 @@ from unittest.mock import patch
from synapse.api.room_versions import RoomVersions
from synapse.events import EventBase, make_event_from_dict
from synapse.events.snapshot import EventContext
from synapse.types import JsonDict, create_requester
from synapse.visibility import filter_events_for_client, filter_events_for_server
@ -73,6 +74,39 @@ class FilterEventsForServerTestCase(unittest.HomeserverTestCase):
self.assertEqual(events_to_filter[i].event_id, filtered[i].event_id)
self.assertEqual(filtered[i].content["a"], "b")
def test_filter_outlier(self) -> None:
# outlier events must be returned, for the good of the collective federation
self.get_success(self._inject_room_member("@resident:remote_hs"))
self.get_success(self._inject_visibility("@resident:remote_hs", "joined"))
outlier = self.get_success(self._inject_outlier())
self.assertEqual(
self.get_success(
filter_events_for_server(self.storage, "remote_hs", [outlier])
),
[outlier],
)
# it should also work when there are other events in the list
evt = self.get_success(self._inject_message("@unerased:local_hs"))
filtered = self.get_success(
filter_events_for_server(self.storage, "remote_hs", [outlier, evt])
)
self.assertEqual(len(filtered), 2, f"expected 2 results, got: {filtered}")
self.assertEqual(filtered[0], outlier)
self.assertEqual(filtered[1].event_id, evt.event_id)
self.assertEqual(filtered[1].content, evt.content)
# ... but other servers should only be able to see the outlier (the other should
# be redacted)
filtered = self.get_success(
filter_events_for_server(self.storage, "other_server", [outlier, evt])
)
self.assertEqual(filtered[0], outlier)
self.assertEqual(filtered[1].event_id, evt.event_id)
self.assertNotIn("body", filtered[1].content)
def test_erased_user(self) -> None:
# 4 message events, from erased and unerased users, with a membership
# change in the middle of them.
@ -187,6 +221,25 @@ class FilterEventsForServerTestCase(unittest.HomeserverTestCase):
self.get_success(self.storage.persistence.persist_event(event, context))
return event
def _inject_outlier(self) -> EventBase:
builder = self.event_builder_factory.for_room_version(
RoomVersions.V1,
{
"type": "m.room.member",
"sender": "@test:user",
"state_key": "@test:user",
"room_id": TEST_ROOM_ID,
"content": {"membership": "join"},
},
)
event = self.get_success(builder.build(prev_event_ids=[], auth_event_ids=[]))
event.internal_metadata.outlier = True
self.get_success(
self.storage.persistence.persist_event(event, EventContext.for_outlier())
)
return event
class FilterEventsForClientTestCase(unittest.FederatingHomeserverTestCase):
def test_out_of_band_invite_rejection(self):