mirror of
https://git.anonymousland.org/anonymousland/synapse.git
synced 2024-12-25 06:29:22 -05:00
159 lines
4.7 KiB
Python
159 lines
4.7 KiB
Python
# -*- coding: utf-8 -*-
|
|
# Copyright 2015, 2016 OpenMarket Ltd
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License");
|
|
# you may not use this file except in compliance with the License.
|
|
# You may obtain a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS,
|
|
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
# See the License for the specific language governing permissions and
|
|
# limitations under the License.
|
|
|
|
|
|
from twisted.internet import defer
|
|
|
|
from synapse.events.utils import prune_event
|
|
|
|
from synapse.crypto.event_signing import check_event_content_hash
|
|
|
|
from synapse.api.errors import SynapseError
|
|
|
|
from synapse.util import unwrapFirstError
|
|
|
|
import logging
|
|
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
|
|
class FederationBase(object):
|
|
@defer.inlineCallbacks
|
|
def _check_sigs_and_hash_and_fetch(self, origin, pdus, outlier=False,
|
|
include_none=False):
|
|
"""Takes a list of PDUs and checks the signatures and hashs of each
|
|
one. If a PDU fails its signature check then we check if we have it in
|
|
the database and if not then request if from the originating server of
|
|
that PDU.
|
|
|
|
If a PDU fails its content hash check then it is redacted.
|
|
|
|
The given list of PDUs are not modified, instead the function returns
|
|
a new list.
|
|
|
|
Args:
|
|
pdu (list)
|
|
outlier (bool)
|
|
|
|
Returns:
|
|
Deferred : A list of PDUs that have valid signatures and hashes.
|
|
"""
|
|
deferreds = self._check_sigs_and_hashes(pdus)
|
|
|
|
def callback(pdu):
|
|
return pdu
|
|
|
|
def errback(failure, pdu):
|
|
failure.trap(SynapseError)
|
|
return None
|
|
|
|
def try_local_db(res, pdu):
|
|
if not res:
|
|
# Check local db.
|
|
return self.store.get_event(
|
|
pdu.event_id,
|
|
allow_rejected=True,
|
|
allow_none=True,
|
|
)
|
|
return res
|
|
|
|
def try_remote(res, pdu):
|
|
if not res and pdu.origin != origin:
|
|
return self.get_pdu(
|
|
destinations=[pdu.origin],
|
|
event_id=pdu.event_id,
|
|
outlier=outlier,
|
|
timeout=10000,
|
|
).addErrback(lambda e: None)
|
|
return res
|
|
|
|
def warn(res, pdu):
|
|
if not res:
|
|
logger.warn(
|
|
"Failed to find copy of %s with valid signature",
|
|
pdu.event_id,
|
|
)
|
|
return res
|
|
|
|
for pdu, deferred in zip(pdus, deferreds):
|
|
deferred.addCallbacks(
|
|
callback, errback, errbackArgs=[pdu]
|
|
).addCallback(
|
|
try_local_db, pdu
|
|
).addCallback(
|
|
try_remote, pdu
|
|
).addCallback(
|
|
warn, pdu
|
|
)
|
|
|
|
valid_pdus = yield defer.gatherResults(
|
|
deferreds,
|
|
consumeErrors=True
|
|
).addErrback(unwrapFirstError)
|
|
|
|
if include_none:
|
|
defer.returnValue(valid_pdus)
|
|
else:
|
|
defer.returnValue([p for p in valid_pdus if p])
|
|
|
|
def _check_sigs_and_hash(self, pdu):
|
|
return self._check_sigs_and_hashes([pdu])[0]
|
|
|
|
def _check_sigs_and_hashes(self, pdus):
|
|
"""Throws a SynapseError if a PDU does not have the correct
|
|
signatures.
|
|
|
|
Returns:
|
|
FrozenEvent: Either the given event or it redacted if it failed the
|
|
content hash check.
|
|
"""
|
|
|
|
redacted_pdus = [
|
|
prune_event(pdu)
|
|
for pdu in pdus
|
|
]
|
|
|
|
deferreds = self.keyring.verify_json_objects_for_server([
|
|
(p.origin, p.get_pdu_json())
|
|
for p in redacted_pdus
|
|
])
|
|
|
|
def callback(_, pdu, redacted):
|
|
if not check_event_content_hash(pdu):
|
|
logger.warn(
|
|
"Event content has been tampered, redacting %s: %s",
|
|
pdu.event_id, pdu.get_pdu_json()
|
|
)
|
|
return redacted
|
|
return pdu
|
|
|
|
def errback(failure, pdu):
|
|
failure.trap(SynapseError)
|
|
logger.warn(
|
|
"Signature check failed for %s",
|
|
pdu.event_id,
|
|
)
|
|
return failure
|
|
|
|
for deferred, pdu, redacted in zip(deferreds, pdus, redacted_pdus):
|
|
deferred.addCallbacks(
|
|
callback, errback,
|
|
callbackArgs=[pdu, redacted],
|
|
errbackArgs=[pdu],
|
|
)
|
|
|
|
return deferreds
|