Persist auth/state events at backwards extremities when we fetch them (#6526)
The main point here is to make sure that the state returned by _get_state_in_room has been authed before we try to use it as state in the room.pull/6560/head
Richard van der Hoff
Richard van der Hoff
parent
83895316d4
commit
ff773ff724
|
|
@ -0,0 +1 @@
|
|||
Fix a bug which could cause the federation server to incorrectly return errors when handling certain obscure event graphs.
|
||||
|
|
@ -64,8 +64,7 @@ from synapse.replication.http.federation import (
|
|||
from synapse.replication.http.membership import ReplicationUserJoinedLeftRoomRestServlet
|
||||
from synapse.state import StateResolutionStore, resolve_events_with_store
|
||||
from synapse.types import UserID, get_domain_from_id
|
||||
from synapse.util import batch_iter, unwrapFirstError
|
||||
from synapse.util.async_helpers import Linearizer
|
||||
from synapse.util.async_helpers import Linearizer, concurrently_execute
|
||||
from synapse.util.distributor import user_joined_room
|
||||
from synapse.util.retryutils import NotRetryingDestination
|
||||
from synapse.visibility import filter_events_for_server
|
||||
|
|
@ -240,7 +239,6 @@ class FederationHandler(BaseHandler):
|
|||
return None
|
||||
|
||||
state = None
|
||||
auth_chain = []
|
||||
|
||||
# Get missing pdus if necessary.
|
||||
if not pdu.internal_metadata.is_outlier():
|
||||
|
|
@ -346,7 +344,6 @@ class FederationHandler(BaseHandler):
|
|||
|
||||
# Calculate the state after each of the previous events, and
|
||||
# resolve them to find the correct state at the current event.
|
||||
auth_chains = set()
|
||||
event_map = {event_id: pdu}
|
||||
try:
|
||||
# Get the state of the events we know about
|
||||
|
|
@ -370,24 +367,14 @@ class FederationHandler(BaseHandler):
|
|||
p,
|
||||
)
|
||||
|
||||
room_version = yield self.store.get_room_version(room_id)
|
||||
|
||||
with nested_logging_context(p):
|
||||
# note that if any of the missing prevs share missing state or
|
||||
# auth events, the requests to fetch those events are deduped
|
||||
# by the get_pdu_cache in federation_client.
|
||||
(
|
||||
remote_state,
|
||||
got_auth_chain,
|
||||
) = yield self._get_state_for_room(
|
||||
(remote_state, _,) = yield self._get_state_for_room(
|
||||
origin, room_id, p, include_event_in_state=True
|
||||
)
|
||||
|
||||
# XXX hrm I'm not convinced that duplicate events will compare
|
||||
# for equality, so I'm not sure this does what the author
|
||||
# hoped.
|
||||
auth_chains.update(got_auth_chain)
|
||||
|
||||
remote_state_map = {
|
||||
(x.type, x.state_key): x.event_id for x in remote_state
|
||||
}
|
||||
|
|
@ -396,6 +383,7 @@ class FederationHandler(BaseHandler):
|
|||
for x in remote_state:
|
||||
event_map[x.event_id] = x
|
||||
|
||||
room_version = yield self.store.get_room_version(room_id)
|
||||
state_map = yield resolve_events_with_store(
|
||||
room_id,
|
||||
room_version,
|
||||
|
|
@ -417,7 +405,6 @@ class FederationHandler(BaseHandler):
|
|||
event_map.update(evs)
|
||||
|
||||
state = [event_map[e] for e in six.itervalues(state_map)]
|
||||
auth_chain = list(auth_chains)
|
||||
except Exception:
|
||||
logger.warning(
|
||||
"[%s %s] Error attempting to resolve state at missing "
|
||||
|
|
@ -433,9 +420,7 @@ class FederationHandler(BaseHandler):
|
|||
affected=event_id,
|
||||
)
|
||||
|
||||
yield self._process_received_pdu(
|
||||
origin, pdu, state=state, auth_chain=auth_chain
|
||||
)
|
||||
yield self._process_received_pdu(origin, pdu, state=state)
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def _get_missing_events_for_pdu(self, origin, pdu, prevs, min_depth):
|
||||
|
|
@ -638,6 +623,8 @@ class FederationHandler(BaseHandler):
|
|||
room_id (str)
|
||||
event_ids (Iterable[str])
|
||||
|
||||
Persists any events we don't already have as outliers.
|
||||
|
||||
If we fail to fetch any of the events, a warning will be logged, and the event
|
||||
will be omitted from the result. Likewise, any events which turn out not to
|
||||
be in the given room.
|
||||
|
|
@ -657,27 +644,15 @@ class FederationHandler(BaseHandler):
|
|||
room_id,
|
||||
)
|
||||
|
||||
room_version = yield self.store.get_room_version(room_id)
|
||||
|
||||
# XXX 20 requests at once? really?
|
||||
for batch in batch_iter(missing_events, 20):
|
||||
deferreds = [
|
||||
run_in_background(
|
||||
self.federation_client.get_pdu,
|
||||
destinations=[destination],
|
||||
event_id=e_id,
|
||||
room_version=room_version,
|
||||
)
|
||||
for e_id in batch
|
||||
]
|
||||
|
||||
res = yield make_deferred_yieldable(
|
||||
defer.DeferredList(deferreds, consumeErrors=True)
|
||||
yield self._get_events_and_persist(
|
||||
destination=destination, room_id=room_id, events=missing_events
|
||||
)
|
||||
|
||||
for success, result in res:
|
||||
if success and result:
|
||||
fetched_events[result.event_id] = result
|
||||
# we need to make sure we re-load from the database to get the rejected
|
||||
# state correct.
|
||||
fetched_events.update(
|
||||
(yield self.store.get_events(missing_events, allow_rejected=True))
|
||||
)
|
||||
|
||||
# check for events which were in the wrong room.
|
||||
#
|
||||
|
|
@ -707,50 +682,24 @@ class FederationHandler(BaseHandler):
|
|||
return fetched_events
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def _process_received_pdu(self, origin, event, state, auth_chain):
|
||||
def _process_received_pdu(self, origin, event, state):
|
||||
""" Called when we have a new pdu. We need to do auth checks and put it
|
||||
through the StateHandler.
|
||||
|
||||
Args:
|
||||
origin: server sending the event
|
||||
|
||||
event: event to be persisted
|
||||
|
||||
state: Normally None, but if we are handling a gap in the graph
|
||||
(ie, we are missing one or more prev_events), the resolved state at the
|
||||
event
|
||||
"""
|
||||
room_id = event.room_id
|
||||
event_id = event.event_id
|
||||
|
||||
logger.debug("[%s %s] Processing event: %s", room_id, event_id, event)
|
||||
|
||||
event_ids = set()
|
||||
if state:
|
||||
event_ids |= {e.event_id for e in state}
|
||||
if auth_chain:
|
||||
event_ids |= {e.event_id for e in auth_chain}
|
||||
|
||||
seen_ids = yield self.store.have_seen_events(event_ids)
|
||||
|
||||
if state and auth_chain is not None:
|
||||
# If we have any state or auth_chain given to us by the replication
|
||||
# layer, then we should handle them (if we haven't before.)
|
||||
|
||||
event_infos = []
|
||||
|
||||
for e in itertools.chain(auth_chain, state):
|
||||
if e.event_id in seen_ids:
|
||||
continue
|
||||
e.internal_metadata.outlier = True
|
||||
auth_ids = e.auth_event_ids()
|
||||
auth = {
|
||||
(e.type, e.state_key): e
|
||||
for e in auth_chain
|
||||
if e.event_id in auth_ids or e.type == EventTypes.Create
|
||||
}
|
||||
event_infos.append(_NewEventInfo(event=e, auth_events=auth))
|
||||
seen_ids.add(e.event_id)
|
||||
|
||||
logger.info(
|
||||
"[%s %s] persisting newly-received auth/state events %s",
|
||||
room_id,
|
||||
event_id,
|
||||
[e.event.event_id for e in event_infos],
|
||||
)
|
||||
yield self._handle_new_events(origin, event_infos)
|
||||
|
||||
try:
|
||||
context = yield self._handle_new_event(origin, event, state=state)
|
||||
except AuthError as e:
|
||||
|
|
@ -806,8 +755,6 @@ class FederationHandler(BaseHandler):
|
|||
if dest == self.server_name:
|
||||
raise SynapseError(400, "Can't backfill from self.")
|
||||
|
||||
room_version = yield self.store.get_room_version(room_id)
|
||||
|
||||
events = yield self.federation_client.backfill(
|
||||
dest, room_id, limit=limit, extremities=extremities
|
||||
)
|
||||
|
|
@ -836,6 +783,9 @@ class FederationHandler(BaseHandler):
|
|||
|
||||
event_ids = set(e.event_id for e in events)
|
||||
|
||||
# build a list of events whose prev_events weren't in the batch.
|
||||
# (XXX: this will include events whose prev_events we already have; that doesn't
|
||||
# sound right?)
|
||||
edges = [ev.event_id for ev in events if set(ev.prev_event_ids()) - event_ids]
|
||||
|
||||
logger.info("backfill: Got %d events with %d edges", len(events), len(edges))
|
||||
|
|
@ -864,95 +814,11 @@ class FederationHandler(BaseHandler):
|
|||
auth_events.update(
|
||||
{e_id: event_map[e_id] for e_id in required_auth if e_id in event_map}
|
||||
)
|
||||
missing_auth = required_auth - set(auth_events)
|
||||
failed_to_fetch = set()
|
||||
|
||||
# Try and fetch any missing auth events from both DB and remote servers.
|
||||
# We repeatedly do this until we stop finding new auth events.
|
||||
while missing_auth - failed_to_fetch:
|
||||
logger.info("Missing auth for backfill: %r", missing_auth)
|
||||
ret_events = yield self.store.get_events(missing_auth - failed_to_fetch)
|
||||
auth_events.update(ret_events)
|
||||
|
||||
required_auth.update(
|
||||
a_id for event in ret_events.values() for a_id in event.auth_event_ids()
|
||||
)
|
||||
missing_auth = required_auth - set(auth_events)
|
||||
|
||||
if missing_auth - failed_to_fetch:
|
||||
logger.info(
|
||||
"Fetching missing auth for backfill: %r",
|
||||
missing_auth - failed_to_fetch,
|
||||
)
|
||||
|
||||
results = yield make_deferred_yieldable(
|
||||
defer.gatherResults(
|
||||
[
|
||||
run_in_background(
|
||||
self.federation_client.get_pdu,
|
||||
[dest],
|
||||
event_id,
|
||||
room_version=room_version,
|
||||
outlier=True,
|
||||
timeout=10000,
|
||||
)
|
||||
for event_id in missing_auth - failed_to_fetch
|
||||
],
|
||||
consumeErrors=True,
|
||||
)
|
||||
).addErrback(unwrapFirstError)
|
||||
auth_events.update({a.event_id: a for a in results if a})
|
||||
required_auth.update(
|
||||
a_id
|
||||
for event in results
|
||||
if event
|
||||
for a_id in event.auth_event_ids()
|
||||
)
|
||||
missing_auth = required_auth - set(auth_events)
|
||||
|
||||
failed_to_fetch = missing_auth - set(auth_events)
|
||||
|
||||
seen_events = yield self.store.have_seen_events(
|
||||
set(auth_events.keys()) | set(state_events.keys())
|
||||
)
|
||||
|
||||
# We now have a chunk of events plus associated state and auth chain to
|
||||
# persist. We do the persistence in two steps:
|
||||
# 1. Auth events and state get persisted as outliers, plus the
|
||||
# backward extremities get persisted (as non-outliers).
|
||||
# 2. The rest of the events in the chunk get persisted one by one, as
|
||||
# each one depends on the previous event for its state.
|
||||
#
|
||||
# The important thing is that events in the chunk get persisted as
|
||||
# non-outliers, including when those events are also in the state or
|
||||
# auth chain. Caution must therefore be taken to ensure that they are
|
||||
# not accidentally marked as outliers.
|
||||
|
||||
# Step 1a: persist auth events that *don't* appear in the chunk
|
||||
ev_infos = []
|
||||
for a in auth_events.values():
|
||||
# We only want to persist auth events as outliers that we haven't
|
||||
# seen and aren't about to persist as part of the backfilled chunk.
|
||||
if a.event_id in seen_events or a.event_id in event_map:
|
||||
continue
|
||||
|
||||
a.internal_metadata.outlier = True
|
||||
ev_infos.append(
|
||||
_NewEventInfo(
|
||||
event=a,
|
||||
auth_events={
|
||||
(
|
||||
auth_events[a_id].type,
|
||||
auth_events[a_id].state_key,
|
||||
): auth_events[a_id]
|
||||
for a_id in a.auth_event_ids()
|
||||
if a_id in auth_events
|
||||
},
|
||||
)
|
||||
)
|
||||
|
||||
# Step 1b: persist the events in the chunk we fetched state for (i.e.
|
||||
# the backwards extremities) as non-outliers.
|
||||
# Step 1: persist the events in the chunk we fetched state for (i.e.
|
||||
# the backwards extremities), with custom auth events and state
|
||||
for e_id in events_to_state:
|
||||
# For paranoia we ensure that these events are marked as
|
||||
# non-outliers
|
||||
|
|
@ -1194,6 +1060,57 @@ class FederationHandler(BaseHandler):
|
|||
|
||||
return False
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def _get_events_and_persist(
|
||||
self, destination: str, room_id: str, events: Iterable[str]
|
||||
):
|
||||
"""Fetch the given events from a server, and persist them as outliers.
|
||||
|
||||
Logs a warning if we can't find the given event.
|
||||
"""
|
||||
|
||||
room_version = yield self.store.get_room_version(room_id)
|
||||
|
||||
event_infos = []
|
||||
|
||||
async def get_event(event_id: str):
|
||||
with nested_logging_context(event_id):
|
||||
try:
|
||||
event = await self.federation_client.get_pdu(
|
||||
[destination], event_id, room_version, outlier=True,
|
||||
)
|
||||
if event is None:
|
||||
logger.warning(
|
||||
"Server %s didn't return event %s", destination, event_id,
|
||||
)
|
||||
return
|
||||
|
||||
# recursively fetch the auth events for this event
|
||||
auth_events = await self._get_events_from_store_or_dest(
|
||||
destination, room_id, event.auth_event_ids()
|
||||
)
|
||||
auth = {}
|
||||
for auth_event_id in event.auth_event_ids():
|
||||
ae = auth_events.get(auth_event_id)
|
||||
if ae:
|
||||
auth[(ae.type, ae.state_key)] = ae
|
||||
|
||||
event_infos.append(_NewEventInfo(event, None, auth))
|
||||
|
||||
except Exception as e:
|
||||
logger.warning(
|
||||
"Error fetching missing state/auth event %s: %s %s",
|
||||
event_id,
|
||||
type(e),
|
||||
e,
|
||||
)
|
||||
|
||||
yield concurrently_execute(get_event, events, 5)
|
||||
|
||||
yield self._handle_new_events(
|
||||
destination, event_infos,
|
||||
)
|
||||
|
||||
def _sanity_check_event(self, ev):
|
||||
"""
|
||||
Do some early sanity checks of a received event
|
||||
|
|
|
|||
|
|
@ -140,8 +140,8 @@ def concurrently_execute(func, args, limit):
|
|||
|
||||
Args:
|
||||
func (func): Function to execute, should return a deferred or coroutine.
|
||||
args (list): List of arguments to pass to func, each invocation of func
|
||||
gets a signle argument.
|
||||
args (Iterable): List of arguments to pass to func, each invocation of func
|
||||
gets a single argument.
|
||||
limit (int): Maximum number of conccurent executions.
|
||||
|
||||
Returns:
|
||||
|
|
|
|||
Loading…
Reference in New Issue