forked-synapse/synapse/handlers/e2e_keys.py
Hubert Chathi 7b3bc755a3 remove unused and unnecessary check for FederationDeniedError (#5645)
FederationDeniedError is a subclass of SynapseError, which is a subclass of
CodeMessageException, so if e is a FederationDeniedError, then this check for
FederationDeniedError will never be reached since it will be caught by the
check for CodeMessageException above.  The check for CodeMessageException does
almost the same thing as this check (since FederationDeniedError initialises
with code=403 and msg="Federation denied with %s."), so may as well just keep
allowing it to handle this case.
2019-07-09 18:37:39 +01:00

374 lines
14 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2016 OpenMarket Ltd
# Copyright 2018 New Vector 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.
import logging
from six import iteritems
from canonicaljson import encode_canonical_json, json
from twisted.internet import defer
from synapse.api.errors import CodeMessageException, SynapseError
from synapse.logging.context import make_deferred_yieldable, run_in_background
from synapse.types import UserID, get_domain_from_id
from synapse.util.retryutils import NotRetryingDestination
logger = logging.getLogger(__name__)
class E2eKeysHandler(object):
def __init__(self, hs):
self.store = hs.get_datastore()
self.federation = hs.get_federation_client()
self.device_handler = hs.get_device_handler()
self.is_mine = hs.is_mine
self.clock = hs.get_clock()
# doesn't really work as part of the generic query API, because the
# query request requires an object POST, but we abuse the
# "query handler" interface.
hs.get_federation_registry().register_query_handler(
"client_keys", self.on_federation_query_client_keys
)
@defer.inlineCallbacks
def query_devices(self, query_body, timeout):
""" Handle a device key query from a client
{
"device_keys": {
"<user_id>": ["<device_id>"]
}
}
->
{
"device_keys": {
"<user_id>": {
"<device_id>": {
...
}
}
}
}
"""
device_keys_query = query_body.get("device_keys", {})
# separate users by domain.
# make a map from domain to user_id to device_ids
local_query = {}
remote_queries = {}
for user_id, device_ids in device_keys_query.items():
# we use UserID.from_string to catch invalid user ids
if self.is_mine(UserID.from_string(user_id)):
local_query[user_id] = device_ids
else:
remote_queries[user_id] = device_ids
# First get local devices.
failures = {}
results = {}
if local_query:
local_result = yield self.query_local_devices(local_query)
for user_id, keys in local_result.items():
if user_id in local_query:
results[user_id] = keys
# Now attempt to get any remote devices from our local cache.
remote_queries_not_in_cache = {}
if remote_queries:
query_list = []
for user_id, device_ids in iteritems(remote_queries):
if device_ids:
query_list.extend((user_id, device_id) for device_id in device_ids)
else:
query_list.append((user_id, None))
user_ids_not_in_cache, remote_results = (
yield self.store.get_user_devices_from_cache(query_list)
)
for user_id, devices in iteritems(remote_results):
user_devices = results.setdefault(user_id, {})
for device_id, device in iteritems(devices):
keys = device.get("keys", None)
device_display_name = device.get("device_display_name", None)
if keys:
result = dict(keys)
unsigned = result.setdefault("unsigned", {})
if device_display_name:
unsigned["device_display_name"] = device_display_name
user_devices[device_id] = result
for user_id in user_ids_not_in_cache:
domain = get_domain_from_id(user_id)
r = remote_queries_not_in_cache.setdefault(domain, {})
r[user_id] = remote_queries[user_id]
# Now fetch any devices that we don't have in our cache
@defer.inlineCallbacks
def do_remote_query(destination):
destination_query = remote_queries_not_in_cache[destination]
try:
remote_result = yield self.federation.query_client_keys(
destination, {"device_keys": destination_query}, timeout=timeout
)
for user_id, keys in remote_result["device_keys"].items():
if user_id in destination_query:
results[user_id] = keys
except Exception as e:
failures[destination] = _exception_to_failure(e)
yield make_deferred_yieldable(
defer.gatherResults(
[
run_in_background(do_remote_query, destination)
for destination in remote_queries_not_in_cache
],
consumeErrors=True,
)
)
defer.returnValue({"device_keys": results, "failures": failures})
@defer.inlineCallbacks
def query_local_devices(self, query):
"""Get E2E device keys for local users
Args:
query (dict[string, list[string]|None): map from user_id to a list
of devices to query (None for all devices)
Returns:
defer.Deferred: (resolves to dict[string, dict[string, dict]]):
map from user_id -> device_id -> device details
"""
local_query = []
result_dict = {}
for user_id, device_ids in query.items():
# we use UserID.from_string to catch invalid user ids
if not self.is_mine(UserID.from_string(user_id)):
logger.warning("Request for keys for non-local user %s", user_id)
raise SynapseError(400, "Not a user here")
if not device_ids:
local_query.append((user_id, None))
else:
for device_id in device_ids:
local_query.append((user_id, device_id))
# make sure that each queried user appears in the result dict
result_dict[user_id] = {}
results = yield self.store.get_e2e_device_keys(local_query)
# Build the result structure, un-jsonify the results, and add the
# "unsigned" section
for user_id, device_keys in results.items():
for device_id, device_info in device_keys.items():
r = dict(device_info["keys"])
r["unsigned"] = {}
display_name = device_info["device_display_name"]
if display_name is not None:
r["unsigned"]["device_display_name"] = display_name
result_dict[user_id][device_id] = r
defer.returnValue(result_dict)
@defer.inlineCallbacks
def on_federation_query_client_keys(self, query_body):
""" Handle a device key query from a federated server
"""
device_keys_query = query_body.get("device_keys", {})
res = yield self.query_local_devices(device_keys_query)
defer.returnValue({"device_keys": res})
@defer.inlineCallbacks
def claim_one_time_keys(self, query, timeout):
local_query = []
remote_queries = {}
for user_id, device_keys in query.get("one_time_keys", {}).items():
# we use UserID.from_string to catch invalid user ids
if self.is_mine(UserID.from_string(user_id)):
for device_id, algorithm in device_keys.items():
local_query.append((user_id, device_id, algorithm))
else:
domain = get_domain_from_id(user_id)
remote_queries.setdefault(domain, {})[user_id] = device_keys
results = yield self.store.claim_e2e_one_time_keys(local_query)
json_result = {}
failures = {}
for user_id, device_keys in results.items():
for device_id, keys in device_keys.items():
for key_id, json_bytes in keys.items():
json_result.setdefault(user_id, {})[device_id] = {
key_id: json.loads(json_bytes)
}
@defer.inlineCallbacks
def claim_client_keys(destination):
device_keys = remote_queries[destination]
try:
remote_result = yield self.federation.claim_client_keys(
destination, {"one_time_keys": device_keys}, timeout=timeout
)
for user_id, keys in remote_result["one_time_keys"].items():
if user_id in device_keys:
json_result[user_id] = keys
except Exception as e:
failures[destination] = _exception_to_failure(e)
yield make_deferred_yieldable(
defer.gatherResults(
[
run_in_background(claim_client_keys, destination)
for destination in remote_queries
],
consumeErrors=True,
)
)
logger.info(
"Claimed one-time-keys: %s",
",".join(
(
"%s for %s:%s" % (key_id, user_id, device_id)
for user_id, user_keys in iteritems(json_result)
for device_id, device_keys in iteritems(user_keys)
for key_id, _ in iteritems(device_keys)
)
),
)
defer.returnValue({"one_time_keys": json_result, "failures": failures})
@defer.inlineCallbacks
def upload_keys_for_user(self, user_id, device_id, keys):
time_now = self.clock.time_msec()
# TODO: Validate the JSON to make sure it has the right keys.
device_keys = keys.get("device_keys", None)
if device_keys:
logger.info(
"Updating device_keys for device %r for user %s at %d",
device_id,
user_id,
time_now,
)
# TODO: Sign the JSON with the server key
changed = yield self.store.set_e2e_device_keys(
user_id, device_id, time_now, device_keys
)
if changed:
# Only notify about device updates *if* the keys actually changed
yield self.device_handler.notify_device_update(user_id, [device_id])
one_time_keys = keys.get("one_time_keys", None)
if one_time_keys:
yield self._upload_one_time_keys_for_user(
user_id, device_id, time_now, one_time_keys
)
# the device should have been registered already, but it may have been
# deleted due to a race with a DELETE request. Or we may be using an
# old access_token without an associated device_id. Either way, we
# need to double-check the device is registered to avoid ending up with
# keys without a corresponding device.
yield self.device_handler.check_device_registered(user_id, device_id)
result = yield self.store.count_e2e_one_time_keys(user_id, device_id)
defer.returnValue({"one_time_key_counts": result})
@defer.inlineCallbacks
def _upload_one_time_keys_for_user(
self, user_id, device_id, time_now, one_time_keys
):
logger.info(
"Adding one_time_keys %r for device %r for user %r at %d",
one_time_keys.keys(),
device_id,
user_id,
time_now,
)
# make a list of (alg, id, key) tuples
key_list = []
for key_id, key_obj in one_time_keys.items():
algorithm, key_id = key_id.split(":")
key_list.append((algorithm, key_id, key_obj))
# First we check if we have already persisted any of the keys.
existing_key_map = yield self.store.get_e2e_one_time_keys(
user_id, device_id, [k_id for _, k_id, _ in key_list]
)
new_keys = [] # Keys that we need to insert. (alg, id, json) tuples.
for algorithm, key_id, key in key_list:
ex_json = existing_key_map.get((algorithm, key_id), None)
if ex_json:
if not _one_time_keys_match(ex_json, key):
raise SynapseError(
400,
(
"One time key %s:%s already exists. "
"Old key: %s; new key: %r"
)
% (algorithm, key_id, ex_json, key),
)
else:
new_keys.append(
(algorithm, key_id, encode_canonical_json(key).decode("ascii"))
)
yield self.store.add_e2e_one_time_keys(user_id, device_id, time_now, new_keys)
def _exception_to_failure(e):
if isinstance(e, CodeMessageException):
return {"status": e.code, "message": str(e)}
if isinstance(e, NotRetryingDestination):
return {"status": 503, "message": "Not ready for retry"}
# include ConnectionRefused and other errors
#
# Note that some Exceptions (notably twisted's ResponseFailed etc) don't
# give a string for e.message, which json then fails to serialize.
return {"status": 503, "message": str(e)}
def _one_time_keys_match(old_key_json, new_key):
old_key = json.loads(old_key_json)
# if either is a string rather than an object, they must match exactly
if not isinstance(old_key, dict) or not isinstance(new_key, dict):
return old_key == new_key
# otherwise, we strip off the 'signatures' if any, because it's legitimate
# for different upload attempts to have different signatures.
old_key.pop("signatures", None)
new_key_copy = dict(new_key)
new_key_copy.pop("signatures", None)
return old_key == new_key_copy