handle federation not telling us about prev_events

This commit is contained in:
Amber Brown 2018-06-27 11:27:32 +01:00
parent cd6bcdaf87
commit 77078d6c8e
4 changed files with 301 additions and 27 deletions

View File

@ -549,7 +549,9 @@ class FederationServer(FederationBase):
affected=pdu.event_id,
)
yield self.handler.on_receive_pdu(origin, pdu, get_missing=True)
yield self.handler.on_receive_pdu(
origin, pdu, get_missing=True, sent_to_us_directly=True,
)
def __str__(self):
return "<ReplicationLayer(%s)>" % self.server_name

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@ -44,6 +44,7 @@ from synapse.util.frozenutils import unfreeze
from synapse.crypto.event_signing import (
compute_event_signature, add_hashes_and_signatures,
)
from synapse.state import resolve_events_with_factory
from synapse.types import UserID, get_domain_from_id
from synapse.events.utils import prune_event
@ -89,7 +90,9 @@ class FederationHandler(BaseHandler):
@defer.inlineCallbacks
@log_function
def on_receive_pdu(self, origin, pdu, get_missing=True):
def on_receive_pdu(
self, origin, pdu, get_missing=True, sent_to_us_directly=False,
):
""" Process a PDU received via a federation /send/ transaction, or
via backfill of missing prev_events
@ -163,7 +166,7 @@ class FederationHandler(BaseHandler):
"Ignoring PDU %s for room %s from %s as we've left the room!",
pdu.event_id, pdu.room_id, origin,
)
return
defer.returnValue(None)
state = None
@ -225,26 +228,54 @@ class FederationHandler(BaseHandler):
list(prevs - seen)[:5],
)
if prevs - seen:
logger.info(
"Still missing %d events for room %r: %r...",
len(prevs - seen), pdu.room_id, list(prevs - seen)[:5]
if sent_to_us_directly and prevs - seen:
# If they have sent it to us directly, and the server
# isn't telling us about the auth events that it's
# made a message referencing, we explode
raise FederationError(
"ERROR",
403,
("Your server isn't divulging details about prev_events "
"referenced in this event."),
affected=pdu.event_id,
)
fetch_state = True
elif prevs - seen:
# If we're walking back up the chain to fetch it, then
# try and find the states. If we can't get the states,
# discard it.
state_groups = []
auth_chains = set()
try:
# Get the ones we know about
ours = yield self.store.get_state_groups(pdu.room_id, list(seen))
state_groups.append(ours)
if fetch_state:
# We need to get the state at this event, since we haven't
# processed all the prev events.
logger.debug(
"_handle_new_pdu getting state for %s",
pdu.room_id
)
try:
state, auth_chain = yield self.replication_layer.get_state_for_room(
origin, pdu.room_id, pdu.event_id,
)
except Exception:
logger.exception("Failed to get state for event: %s", pdu.event_id)
for p in prevs - seen:
state, auth_chain = yield self.replication_layer.get_state_for_room(
origin, pdu.room_id, p
)
auth_chains.update(auth_chain)
state_group = {
(x.type, x.state_key): x.event_id for x in state
}
state_groups.append(state_group)
def fetch(ev_ids):
return self.store.get_events(
ev_ids, get_prev_content=False, check_redacted=False,
)
state = yield resolve_events_with_factory(state_groups, {pdu.event_id: pdu}, fetch)
state = yield self.store.get_events(state.values())
state = state.values()
except Exception:
raise FederationError(
"ERROR",
403,
"We can't get valid state history.",
affected=pdu.event_id,
)
yield self._process_received_pdu(
origin,
@ -322,11 +353,17 @@ class FederationHandler(BaseHandler):
for e in missing_events:
logger.info("Handling found event %s", e.event_id)
yield self.on_receive_pdu(
origin,
e,
get_missing=False
)
try:
yield self.on_receive_pdu(
origin,
e,
get_missing=False
)
except FederationError as e:
if e.code == 403:
logger.warn("Event %s failed history check.")
else:
raise
@log_function
@defer.inlineCallbacks

235
tests/test_federation.py Normal file
View File

@ -0,0 +1,235 @@
from twisted.internet.defer import Deferred, succeed, maybeDeferred
from synapse.util import Clock
from synapse.events import FrozenEvent
from synapse.types import Requester, UserID
from synapse.replication.slave.storage.events import SlavedEventStore
from tests import unittest
from tests.server import make_request, setup_test_homeserver, ThreadedMemoryReactorClock
from mock import Mock
from synapse.api.errors import CodeMessageException, HttpResponseException
class MessageAcceptTests(unittest.TestCase):
def setUp(self):
self.http_client = Mock()
self.reactor = ThreadedMemoryReactorClock()
self.hs_clock = Clock(self.reactor)
self.homeserver = setup_test_homeserver(
http_client=self.http_client, clock=self.hs_clock, reactor=self.reactor
)
user_id = UserID("us", "test")
our_user = Requester(user_id, None, False, None, None)
room_creator = self.homeserver.get_room_creation_handler()
room = room_creator.create_room(
our_user, room_creator.PRESETS_DICT["public_chat"], ratelimit=False
)
self.reactor.advance(0.1)
self.room_id = self.successResultOf(room)["room_id"]
# Figure out what the most recent event is
most_recent = self.successResultOf(
self.homeserver.datastore.get_latest_event_ids_in_room(self.room_id)
)[0]
join_event = FrozenEvent(
{
"room_id": self.room_id,
"sender": "@baduser:test.serv",
"state_key": "@baduser:test.serv",
"event_id": "$join:test.serv",
"depth": 1000,
"origin_server_ts": 1,
"type": "m.room.member",
"origin": "test.servx",
"content": {"membership": "join"},
"auth_events": [],
"prev_state": [(most_recent, {})],
"prev_events": [(most_recent, {})],
}
)
self.handler = self.homeserver.get_handlers().federation_handler
self.handler.do_auth = lambda *a, **b: succeed(True)
self.client = self.homeserver.get_federation_client()
self.client._check_sigs_and_hash_and_fetch = lambda dest, pdus, **k: succeed(
pdus
)
# Send the join, it should return None (which is not an error)
d = self.handler.on_receive_pdu(
"test.serv", join_event, sent_to_us_directly=True
)
self.reactor.advance(1)
self.assertEqual(self.successResultOf(d), None)
# Make sure we actually joined the room
self.assertEqual(
self.successResultOf(
self.homeserver.datastore.get_latest_event_ids_in_room(self.room_id)
)[0],
"$join:test.serv",
)
def test_cant_hide_direct_ancestors(self):
"""
If you send a message, you must be able to provide the direct
prev_events that said event references.
"""
def post_json(destination, path, data, headers=None, timeout=0):
# If it asks us for new missing events, give them NOTHING
if path.startswith("/_matrix/federation/v1/get_missing_events/"):
return {"events": []}
self.http_client.post_json = post_json
# Figure out what the most recent event is
most_recent = self.successResultOf(
self.homeserver.datastore.get_latest_event_ids_in_room(self.room_id)
)[0]
# Now lie about an event
lying_event = FrozenEvent(
{
"room_id": self.room_id,
"sender": "@baduser:test.serv",
"event_id": "one:test.serv",
"depth": 1000,
"origin_server_ts": 1,
"type": "m.room.message",
"origin": "test.serv",
"content": "hewwo?",
"auth_events": [],
"prev_events": [("two:test.serv", {}), (most_recent, {})],
}
)
d = self.handler.on_receive_pdu(
"test.serv", lying_event, sent_to_us_directly=True
)
# Step the reactor, so the database fetches come back
self.reactor.advance(1)
# on_receive_pdu should throw an error
failure = self.failureResultOf(d)
self.assertEqual(
failure.value.args[0],
(
"ERROR 403: Your server isn't divulging details about prev_events "
"referenced in this event."
),
)
# Make sure the invalid event isn't there
extrem = self.homeserver.datastore.get_latest_event_ids_in_room(self.room_id)
self.assertEqual(self.successResultOf(extrem)[0], "$join:test.serv")
@unittest.DEBUG
def test_cant_hide_past_history(self):
"""
If you send a message, you must be able to provide the direct
prev_events that said event references.
"""
def post_json(destination, path, data, headers=None, timeout=0):
if path.startswith("/_matrix/federation/v1/get_missing_events/"):
return {
"events": [
{
"room_id": self.room_id,
"sender": "@baduser:test.serv",
"event_id": "three:test.serv",
"depth": 1000,
"origin_server_ts": 1,
"type": "m.room.message",
"origin": "test.serv",
"content": "hewwo?",
"auth_events": [],
"prev_events": [("four:test.serv", {})],
}
]
}
self.http_client.post_json = post_json
def get_json(destination, path, args, headers=None):
print(destination, path, args)
if path.startswith("/_matrix/federation/v1/state_ids/"):
d = self.successResultOf(
self.homeserver.datastore.get_state_ids_for_event("one:test.serv")
)
return succeed(
{
"pdu_ids": [
y
for x, y in d.items()
if x == ("m.room.member", "@us:test")
],
"auth_chain_ids": d.values(),
}
)
self.http_client.get_json = get_json
# Figure out what the most recent event is
most_recent = self.successResultOf(
self.homeserver.datastore.get_latest_event_ids_in_room(self.room_id)
)[0]
# Make a good event
good_event = FrozenEvent(
{
"room_id": self.room_id,
"sender": "@baduser:test.serv",
"event_id": "one:test.serv",
"depth": 1000,
"origin_server_ts": 1,
"type": "m.room.message",
"origin": "test.serv",
"content": "hewwo?",
"auth_events": [],
"prev_events": [(most_recent, {})],
}
)
d = self.handler.on_receive_pdu(
"test.serv", good_event, sent_to_us_directly=True
)
self.reactor.advance(1)
self.assertEqual(self.successResultOf(d), None)
bad_event = FrozenEvent(
{
"room_id": self.room_id,
"sender": "@baduser:test.serv",
"event_id": "two:test.serv",
"depth": 1000,
"origin_server_ts": 1,
"type": "m.room.message",
"origin": "test.serv",
"content": "hewwo?",
"auth_events": [],
"prev_events": [("one:test.serv", {}), ("three:test.serv", {})],
}
)
d = self.handler.on_receive_pdu(
"test.serv", bad_event, sent_to_us_directly=True
)
self.reactor.advance(1)
extrem = self.homeserver.datastore.get_latest_event_ids_in_room(self.room_id)
self.assertEqual(self.successResultOf(extrem)[0], "two:test.serv")
state = self.homeserver.get_state_handler().get_current_state_ids(self.room_id)
self.reactor.advance(1)
self.assertIn(("m.room.member", "@us:test"), self.successResultOf(state).keys())

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@ -35,7 +35,7 @@ class ToTwistedHandler(logging.Handler):
def emit(self, record):
log_entry = self.format(record)
log_level = record.levelname.lower().replace('warning', 'warn')
self.tx_log.emit(twisted.logger.LogLevel.levelWithName(log_level), log_entry)
self.tx_log.emit(twisted.logger.LogLevel.levelWithName(log_level), log_entry.replace("{", r"(").replace("}", r")"))
handler = ToTwistedHandler()