# -*- 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 .federation_base import FederationBase
from .units import Transaction, Edu
from synapse.util.async import Linearizer
from synapse.util.logutils import log_function
from synapse.util.caches.response_cache import ResponseCache
from synapse.events import FrozenEvent
from synapse.types import get_domain_from_id
import synapse.metrics
from synapse.api.errors import AuthError, FederationError, SynapseError
from synapse.crypto.event_signing import compute_event_signature
import simplejson as json
import logging
logger = logging.getLogger(__name__)
# synapse.federation.federation_server is a silly name
metrics = synapse.metrics.get_metrics_for("synapse.federation.server")
received_pdus_counter = metrics.register_counter("received_pdus")
received_edus_counter = metrics.register_counter("received_edus")
received_queries_counter = metrics.register_counter("received_queries", labels=["type"])
class FederationServer(FederationBase):
def __init__(self, hs):
super(FederationServer, self).__init__(hs)
self.auth = hs.get_auth()
self._server_linearizer = Linearizer("fed_server")
# We cache responses to state queries, as they take a while and often
# come in waves.
self._state_resp_cache = ResponseCache(hs, timeout_ms=30000)
def set_handler(self, handler):
"""Sets the handler that the replication layer will use to communicate
receipt of new PDUs from other home servers. The required methods are
documented on :py:class:`.ReplicationHandler`.
"""
self.handler = handler
def register_edu_handler(self, edu_type, handler):
if edu_type in self.edu_handlers:
raise KeyError("Already have an EDU handler for %s" % (edu_type,))
self.edu_handlers[edu_type] = handler
def register_query_handler(self, query_type, handler):
"""Sets the handler callable that will be used to handle an incoming
federation Query of the given type.
Args:
query_type (str): Category name of the query, which should match
the string used by make_query.
handler (callable): Invoked to handle incoming queries of this type
handler is invoked as:
result = handler(args)
where 'args' is a dict mapping strings to strings of the query
arguments. It should return a Deferred that will eventually yield an
object to encode as JSON.
"""
if query_type in self.query_handlers:
raise KeyError(
"Already have a Query handler for %s" % (query_type,)
)
self.query_handlers[query_type] = handler
@defer.inlineCallbacks
@log_function
def on_backfill_request(self, origin, room_id, versions, limit):
with (yield self._server_linearizer.queue((origin, room_id))):
pdus = yield self.handler.on_backfill_request(
origin, room_id, versions, limit
)
res = self._transaction_from_pdus(pdus).get_dict()
defer.returnValue((200, res))
@defer.inlineCallbacks
@log_function
def on_incoming_transaction(self, transaction_data):
transaction = Transaction(**transaction_data)
received_pdus_counter.inc_by(len(transaction.pdus))
for p in transaction.pdus:
if "unsigned" in p:
unsigned = p["unsigned"]
if "age" in unsigned:
p["age"] = unsigned["age"]
if "age" in p:
p["age_ts"] = int(self._clock.time_msec()) - int(p["age"])
del p["age"]
pdu_list = [
self.event_from_pdu_json(p) for p in transaction.pdus
]
logger.debug("[%s] Got transaction", transaction.transaction_id)
response = yield self.transaction_actions.have_responded(transaction)
if response:
logger.debug(
"[%s] We've already responded to this request",
transaction.transaction_id
)
defer.returnValue(response)
return
logger.debug("[%s] Transaction is new", transaction.transaction_id)
results = []
for pdu in pdu_list:
# check that it's actually being sent from a valid destination to
# workaround bug #1753 in 0.18.5 and 0.18.6
if transaction.origin != get_domain_from_id(pdu.event_id):
# We continue to accept join events from any server; this is
# necessary for the federation join dance to work correctly.
# (When we join over federation, the "helper" server is
# responsible for sending out the join event, rather than the
# origin. See bug #1893).
if not (
pdu.type == 'm.room.member' and
pdu.content and
pdu.content.get("membership", None) == 'join'
):
logger.info(
"Discarding PDU %s from invalid origin %s",
pdu.event_id, transaction.origin
)
continue
else:
logger.info(
"Accepting join PDU %s from %s",
pdu.event_id, transaction.origin
)
try:
yield self._handle_received_pdu(transaction.origin, pdu)
results.append({})
except FederationError as e:
self.send_failure(e, transaction.origin)
results.append({"error": str(e)})
except Exception as e:
results.append({"error": str(e)})
logger.exception("Failed to handle PDU")
if hasattr(transaction, "edus"):
for edu in (Edu(**x) for x in transaction.edus):
yield self.received_edu(
transaction.origin,
edu.edu_type,
edu.content
)
for failure in getattr(transaction, "pdu_failures", []):
logger.info("Got failure %r", failure)
logger.debug("Returning: %s", str(results))
response = {
"pdus": dict(zip(
(p.event_id for p in pdu_list), results
)),
}
yield self.transaction_actions.set_response(
transaction,
200, response
)
defer.returnValue((200, response))
@defer.inlineCallbacks
def received_edu(self, origin, edu_type, content):
received_edus_counter.inc()
if edu_type in self.edu_handlers:
try:
yield self.edu_handlers[edu_type](origin, content)
except SynapseError as e:
logger.info("Failed to handle edu %r: %r", edu_type, e)
except Exception as e:
logger.exception("Failed to handle edu %r", edu_type)
else:
logger.warn("Received EDU of type %s with no handler", edu_type)
@defer.inlineCallbacks
@log_function
def on_context_state_request(self, origin, room_id, event_id):
if not event_id:
raise NotImplementedError("Specify an event")
in_room = yield self.auth.check_host_in_room(room_id, origin)
if not in_room:
raise AuthError(403, "Host not in room.")
result = self._state_resp_cache.get((room_id, event_id))
if not result:
with (yield self._server_linearizer.queue((origin, room_id))):
resp = yield self._state_resp_cache.set(
(room_id, event_id),
self._on_context_state_request_compute(room_id, event_id)
)
else:
resp = yield result
defer.returnValue((200, resp))
@defer.inlineCallbacks
def on_state_ids_request(self, origin, room_id, event_id):
if not event_id:
raise NotImplementedError("Specify an event")
in_room = yield self.auth.check_host_in_room(room_id, origin)
if not in_room:
raise AuthError(403, "Host not in room.")
state_ids = yield self.handler.get_state_ids_for_pdu(
room_id, event_id,
)
auth_chain_ids = yield self.store.get_auth_chain_ids(state_ids)
defer.returnValue((200, {
"pdu_ids": state_ids,
"auth_chain_ids": auth_chain_ids,
}))
@defer.inlineCallbacks
def _on_context_state_request_compute(self, room_id, event_id):
pdus = yield self.handler.get_state_for_pdu(
room_id, event_id,
)
auth_chain = yield self.store.get_auth_chain(
[pdu.event_id for pdu in pdus]
)
for event in auth_chain:
# We sign these again because there was a bug where we
# incorrectly signed things the first time round
if self.hs.is_mine_id(event.event_id):
event.signatures.update(
compute_event_signature(
event,
self.hs.hostname,
self.hs.config.signing_key[0]
)
)
defer.returnValue({
"pdus": [pdu.get_pdu_json() for pdu in pdus],
"auth_chain": [pdu.get_pdu_json() for pdu in auth_chain],
})
@defer.inlineCallbacks
@log_function
def on_pdu_request(self, origin, event_id):
pdu = yield self._get_persisted_pdu(origin, event_id)
if pdu:
defer.returnValue(
(200, self._transaction_from_pdus([pdu]).get_dict())
)
else:
defer.returnValue((404, ""))
@defer.inlineCallbacks
@log_function
def on_pull_request(self, origin, versions):
raise NotImplementedError("Pull transactions not implemented")
@defer.inlineCallbacks
def on_query_request(self, query_type, args):
received_queries_counter.inc(query_type)
if query_type in self.query_handlers:
response = yield self.query_handlers[query_type](args)
defer.returnValue((200, response))
else:
defer.returnValue(
(404, "No handler for Query type '%s'" % (query_type,))
)
@defer.inlineCallbacks
def on_make_join_request(self, room_id, user_id):
pdu = yield self.handler.on_make_join_request(room_id, user_id)
time_now = self._clock.time_msec()
defer.returnValue({"event": pdu.get_pdu_json(time_now)})
@defer.inlineCallbacks
def on_invite_request(self, origin, content):
pdu = self.event_from_pdu_json(content)
ret_pdu = yield self.handler.on_invite_request(origin, pdu)
time_now = self._clock.time_msec()
defer.returnValue((200, {"event": ret_pdu.get_pdu_json(time_now)}))
@defer.inlineCallbacks
def on_send_join_request(self, origin, content):
logger.debug("on_send_join_request: content: %s", content)
pdu = self.event_from_pdu_json(content)
logger.debug("on_send_join_request: pdu sigs: %s", pdu.signatures)
res_pdus = yield self.handler.on_send_join_request(origin, pdu)
time_now = self._clock.time_msec()
defer.returnValue((200, {
"state": [p.get_pdu_json(time_now) for p in res_pdus["state"]],
"auth_chain": [
p.get_pdu_json(time_now) for p in res_pdus["auth_chain"]
],
}))
@defer.inlineCallbacks
def on_make_leave_request(self, room_id, user_id):
pdu = yield self.handler.on_make_leave_request(room_id, user_id)
time_now = self._clock.time_msec()
defer.returnValue({"event": pdu.get_pdu_json(time_now)})
@defer.inlineCallbacks
def on_send_leave_request(self, origin, content):
logger.debug("on_send_leave_request: content: %s", content)
pdu = self.event_from_pdu_json(content)
logger.debug("on_send_leave_request: pdu sigs: %s", pdu.signatures)
yield self.handler.on_send_leave_request(origin, pdu)
defer.returnValue((200, {}))
@defer.inlineCallbacks
def on_event_auth(self, origin, room_id, event_id):
with (yield self._server_linearizer.queue((origin, room_id))):
time_now = self._clock.time_msec()
auth_pdus = yield self.handler.on_event_auth(event_id)
res = {
"auth_chain": [a.get_pdu_json(time_now) for a in auth_pdus],
}
defer.returnValue((200, res))
@defer.inlineCallbacks
def on_query_auth_request(self, origin, content, room_id, event_id):
"""
Content is a dict with keys::
auth_chain (list): A list of events that give the auth chain.
missing (list): A list of event_ids indicating what the other
side (`origin`) think we're missing.
rejects (dict): A mapping from event_id to a 2-tuple of reason
string and a proof (or None) of why the event was rejected.
The keys of this dict give the list of events the `origin` has
rejected.
Args:
origin (str)
content (dict)
event_id (str)
Returns:
Deferred: Results in `dict` with the same format as `content`
"""
with (yield self._server_linearizer.queue((origin, room_id))):
auth_chain = [
self.event_from_pdu_json(e)
for e in content["auth_chain"]
]
signed_auth = yield self._check_sigs_and_hash_and_fetch(
origin, auth_chain, outlier=True
)
ret = yield self.handler.on_query_auth(
origin,
event_id,
signed_auth,
content.get("rejects", []),
content.get("missing", []),
)
time_now = self._clock.time_msec()
send_content = {
"auth_chain": [
e.get_pdu_json(time_now)
for e in ret["auth_chain"]
],
"rejects": ret.get("rejects", []),
"missing": ret.get("missing", []),
}
defer.returnValue(
(200, send_content)
)
@log_function
def on_query_client_keys(self, origin, content):
return self.on_query_request("client_keys", content)
def on_query_user_devices(self, origin, user_id):
return self.on_query_request("user_devices", user_id)
@defer.inlineCallbacks
@log_function
def on_claim_client_keys(self, origin, content):
query = []
for user_id, device_keys in content.get("one_time_keys", {}).items():
for device_id, algorithm in device_keys.items():
query.append((user_id, device_id, algorithm))
results = yield self.store.claim_e2e_one_time_keys(query)
json_result = {}
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.returnValue({"one_time_keys": json_result})
@defer.inlineCallbacks
@log_function
def on_get_missing_events(self, origin, room_id, earliest_events,
latest_events, limit, min_depth):
with (yield self._server_linearizer.queue((origin, room_id))):
logger.info(
"on_get_missing_events: earliest_events: %r, latest_events: %r,"
" limit: %d, min_depth: %d",
earliest_events, latest_events, limit, min_depth
)
missing_events = yield self.handler.on_get_missing_events(
origin, room_id, earliest_events, latest_events, limit, min_depth
)
if len(missing_events) < 5:
logger.info(
"Returning %d events: %r", len(missing_events), missing_events
)
else:
logger.info("Returning %d events", len(missing_events))
time_now = self._clock.time_msec()
defer.returnValue({
"events": [ev.get_pdu_json(time_now) for ev in missing_events],
})
@log_function
def on_openid_userinfo(self, token):
ts_now_ms = self._clock.time_msec()
return self.store.get_user_id_for_open_id_token(token, ts_now_ms)
@log_function
def _get_persisted_pdu(self, origin, event_id, do_auth=True):
""" Get a PDU from the database with given origin and id.
Returns:
Deferred: Results in a `Pdu`.
"""
return self.handler.get_persisted_pdu(
origin, event_id, do_auth=do_auth
)
def _transaction_from_pdus(self, pdu_list):
"""Returns a new Transaction containing the given PDUs suitable for
transmission.
"""
time_now = self._clock.time_msec()
pdus = [p.get_pdu_json(time_now) for p in pdu_list]
return Transaction(
origin=self.server_name,
pdus=pdus,
origin_server_ts=int(time_now),
destination=None,
)
@defer.inlineCallbacks
def _handle_received_pdu(self, origin, pdu):
""" Process a PDU received in a federation /send/ transaction.
Args:
origin (str): server which sent the pdu
pdu (FrozenEvent): received pdu
Returns (Deferred): completes with None
Raises: FederationError if the signatures / hash do not match
"""
# Check signature.
try:
pdu = yield self._check_sigs_and_hash(pdu)
except SynapseError as e:
raise FederationError(
"ERROR",
e.code,
e.msg,
affected=pdu.event_id,
)
yield self.handler.on_receive_pdu(origin, pdu, get_missing=True)
def __str__(self):
return "<ReplicationLayer(%s)>" % self.server_name
def event_from_pdu_json(self, pdu_json, outlier=False):
event = FrozenEvent(
pdu_json
)
event.internal_metadata.outlier = outlier
return event
@defer.inlineCallbacks
def exchange_third_party_invite(
self,
sender_user_id,
target_user_id,
room_id,
signed,
):
ret = yield self.handler.exchange_third_party_invite(
sender_user_id,
target_user_id,
room_id,
signed,
)
defer.returnValue(ret)
@defer.inlineCallbacks
def on_exchange_third_party_invite_request(self, origin, room_id, event_dict):
ret = yield self.handler.on_exchange_third_party_invite_request(
origin, room_id, event_dict
)
defer.returnValue(ret)