synapse-old/synapse/handlers/_base.py

293 lines
10 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2014, 2015 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.api.errors import LimitExceededError, SynapseError, AuthError
from synapse.crypto.event_signing import add_hashes_and_signatures
from synapse.api.constants import Membership, EventTypes
from synapse.types import UserID, RoomAlias
from synapse.util.logcontext import PreserveLoggingContext
from synapse.util import third_party_invites
import logging
logger = logging.getLogger(__name__)
class BaseHandler(object):
def __init__(self, hs):
self.store = hs.get_datastore()
self.auth = hs.get_auth()
self.notifier = hs.get_notifier()
self.state_handler = hs.get_state_handler()
self.distributor = hs.get_distributor()
self.ratelimiter = hs.get_ratelimiter()
self.clock = hs.get_clock()
self.hs = hs
self.signing_key = hs.config.signing_key[0]
self.server_name = hs.hostname
self.event_builder_factory = hs.get_event_builder_factory()
@defer.inlineCallbacks
def _filter_events_for_client(self, user_id, events, is_guest=False):
# Assumes that user has at some point joined the room if not is_guest.
def allowed(event, membership, visibility):
if visibility == "world_readable":
return True
if is_guest:
return False
if membership == Membership.JOIN:
return True
if event.type == EventTypes.RoomHistoryVisibility:
return not is_guest
if visibility == "shared":
return True
elif visibility == "joined":
return membership == Membership.JOIN
elif visibility == "invited":
return membership == Membership.INVITE
return True
event_id_to_state = yield self.store.get_state_for_events(
frozenset(e.event_id for e in events),
types=(
(EventTypes.RoomHistoryVisibility, ""),
(EventTypes.Member, user_id),
)
)
events_to_return = []
for event in events:
state = event_id_to_state[event.event_id]
membership_event = state.get((EventTypes.Member, user_id), None)
if membership_event:
membership = membership_event.membership
else:
membership = None
visibility_event = state.get((EventTypes.RoomHistoryVisibility, ""), None)
if visibility_event:
visibility = visibility_event.content.get("history_visibility", "shared")
else:
visibility = "shared"
should_include = allowed(event, membership, visibility)
if should_include:
events_to_return.append(event)
if is_guest and len(events_to_return) < len(events):
# This indicates that some events in the requested range were not
# visible to guest users. To be safe, we reject the entire request,
# so that we don't have to worry about interpreting visibility
# boundaries.
raise AuthError(403, "User %s does not have permission" % (
user_id
))
defer.returnValue(events_to_return)
def ratelimit(self, user_id):
time_now = self.clock.time()
allowed, time_allowed = self.ratelimiter.send_message(
user_id, time_now,
msg_rate_hz=self.hs.config.rc_messages_per_second,
burst_count=self.hs.config.rc_message_burst_count,
)
if not allowed:
raise LimitExceededError(
retry_after_ms=int(1000*(time_allowed - time_now)),
)
@defer.inlineCallbacks
def _create_new_client_event(self, builder):
latest_ret = yield self.store.get_latest_events_in_room(
builder.room_id,
)
if latest_ret:
depth = max([d for _, _, d in latest_ret]) + 1
else:
depth = 1
prev_events = [(e, h) for e, h, _ in latest_ret]
builder.prev_events = prev_events
builder.depth = depth
state_handler = self.state_handler
context = yield state_handler.compute_event_context(builder)
if builder.is_state():
builder.prev_state = yield self.store.add_event_hashes(
context.prev_state_events
)
yield self.auth.add_auth_events(builder, context)
add_hashes_and_signatures(
builder, self.server_name, self.signing_key
)
event = builder.build()
logger.debug(
"Created event %s with current state: %s",
event.event_id, context.current_state,
)
defer.returnValue(
(event, context,)
)
@defer.inlineCallbacks
def handle_new_client_event(self, event, context, extra_destinations=[],
extra_users=[], suppress_auth=False):
# We now need to go and hit out to wherever we need to hit out to.
if not suppress_auth:
self.auth.check(event, auth_events=context.current_state)
if event.type == EventTypes.CanonicalAlias:
# Check the alias is acually valid (at this time at least)
room_alias_str = event.content.get("alias", None)
if room_alias_str:
room_alias = RoomAlias.from_string(room_alias_str)
directory_handler = self.hs.get_handlers().directory_handler
mapping = yield directory_handler.get_association(room_alias)
if mapping["room_id"] != event.room_id:
raise SynapseError(
400,
"Room alias %s does not point to the room" % (
room_alias_str,
)
)
if (
event.type == EventTypes.Member and
event.content["membership"] == Membership.JOIN and
third_party_invites.join_has_third_party_invite(event.content)
):
yield third_party_invites.check_key_valid(
self.hs.get_simple_http_client(),
event
)
federation_handler = self.hs.get_handlers().federation_handler
if event.type == EventTypes.Member:
if event.content["membership"] == Membership.INVITE:
event.unsigned["invite_room_state"] = [
{
"type": e.type,
"state_key": e.state_key,
"content": e.content,
"sender": e.sender,
}
for k, e in context.current_state.items()
if e.type in (
EventTypes.JoinRules,
EventTypes.CanonicalAlias,
EventTypes.RoomAvatar,
EventTypes.Name,
)
]
invitee = UserID.from_string(event.state_key)
if not self.hs.is_mine(invitee):
# TODO: Can we add signature from remote server in a nicer
# way? If we have been invited by a remote server, we need
# to get them to sign the event.
returned_invite = yield federation_handler.send_invite(
invitee.domain,
event,
)
event.unsigned.pop("room_state", None)
# TODO: Make sure the signatures actually are correct.
event.signatures.update(
returned_invite.signatures
)
if event.type == EventTypes.Redaction:
if self.auth.check_redaction(event, auth_events=context.current_state):
original_event = yield self.store.get_event(
event.redacts,
check_redacted=False,
get_prev_content=False,
allow_rejected=False,
allow_none=False
)
if event.user_id != original_event.user_id:
raise AuthError(
403,
"You don't have permission to redact events"
)
(event_stream_id, max_stream_id) = yield self.store.persist_event(
event, context=context
)
destinations = set(extra_destinations)
for k, s in context.current_state.items():
try:
if k[0] == EventTypes.Member:
if s.content["membership"] == Membership.JOIN:
destinations.add(
UserID.from_string(s.state_key).domain
)
except SynapseError:
logger.warn(
"Failed to get destination from event %s", s.event_id
)
with PreserveLoggingContext():
# Don't block waiting on waking up all the listeners.
notify_d = self.notifier.on_new_room_event(
event, event_stream_id, max_stream_id,
extra_users=extra_users
)
def log_failure(f):
logger.warn(
"Failed to notify about %s: %s",
event.event_id, f.value
)
notify_d.addErrback(log_failure)
# If invite, remove room_state from unsigned before sending.
event.unsigned.pop("invite_room_state", None)
federation_handler.handle_new_event(
event, destinations=destinations,
)