832 lines
		
	
	
		
			31 KiB
		
	
	
	
		
			Python
		
	
	
			
		
		
	
	
			832 lines
		
	
	
		
			31 KiB
		
	
	
	
		
			Python
		
	
	
| # -*- coding: utf-8 -*-
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| # Copyright 2014 - 2016 OpenMarket Ltd
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| #
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| # Licensed under the Apache License, Version 2.0 (the "License");
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| # you may not use this file except in compliance with the License.
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| # You may obtain a copy of the License at
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| #
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| #     http://www.apache.org/licenses/LICENSE-2.0
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| #
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| # Unless required by applicable law or agreed to in writing, software
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| # distributed under the License is distributed on an "AS IS" BASIS,
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| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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| # See the License for the specific language governing permissions and
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| # limitations under the License.
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| 
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| import logging
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| 
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| from six import itervalues
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| 
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| import pymacaroons
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| from netaddr import IPAddress
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| 
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| from twisted.internet import defer
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| 
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| import synapse.types
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| from synapse import event_auth
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| from synapse.api.constants import EventTypes, JoinRules, Membership
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| from synapse.api.errors import AuthError, Codes, ResourceLimitError
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| from synapse.config.server import is_threepid_reserved
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| from synapse.types import UserID
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| from synapse.util.caches import CACHE_SIZE_FACTOR, register_cache
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| from synapse.util.caches.lrucache import LruCache
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| from synapse.util.metrics import Measure
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| 
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| logger = logging.getLogger(__name__)
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| 
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| 
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| AuthEventTypes = (
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|     EventTypes.Create, EventTypes.Member, EventTypes.PowerLevels,
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|     EventTypes.JoinRules, EventTypes.RoomHistoryVisibility,
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|     EventTypes.ThirdPartyInvite,
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| )
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| 
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| # guests always get this device id.
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| GUEST_DEVICE_ID = "guest_device"
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| 
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| 
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| class _InvalidMacaroonException(Exception):
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|     pass
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| 
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| 
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| class Auth(object):
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|     """
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|     FIXME: This class contains a mix of functions for authenticating users
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|     of our client-server API and authenticating events added to room graphs.
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|     """
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|     def __init__(self, hs):
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|         self.hs = hs
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|         self.clock = hs.get_clock()
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|         self.store = hs.get_datastore()
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|         self.state = hs.get_state_handler()
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|         self.TOKEN_NOT_FOUND_HTTP_STATUS = 401
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| 
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|         self.token_cache = LruCache(CACHE_SIZE_FACTOR * 10000)
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|         register_cache("cache", "token_cache", self.token_cache)
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| 
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|     @defer.inlineCallbacks
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|     def check_from_context(self, room_version, event, context, do_sig_check=True):
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|         prev_state_ids = yield context.get_prev_state_ids(self.store)
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|         auth_events_ids = yield self.compute_auth_events(
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|             event, prev_state_ids, for_verification=True,
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|         )
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|         auth_events = yield self.store.get_events(auth_events_ids)
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|         auth_events = {
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|             (e.type, e.state_key): e for e in itervalues(auth_events)
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|         }
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|         self.check(
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|             room_version, event,
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|             auth_events=auth_events, do_sig_check=do_sig_check,
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|         )
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| 
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|     def check(self, room_version, event, auth_events, do_sig_check=True):
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|         """ Checks if this event is correctly authed.
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| 
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|         Args:
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|             room_version (str): version of the room
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|             event: the event being checked.
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|             auth_events (dict: event-key -> event): the existing room state.
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| 
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| 
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|         Returns:
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|             True if the auth checks pass.
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|         """
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|         with Measure(self.clock, "auth.check"):
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|             event_auth.check(
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|                 room_version, event, auth_events, do_sig_check=do_sig_check
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|             )
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| 
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|     @defer.inlineCallbacks
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|     def check_joined_room(self, room_id, user_id, current_state=None):
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|         """Check if the user is currently joined in the room
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|         Args:
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|             room_id(str): The room to check.
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|             user_id(str): The user to check.
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|             current_state(dict): Optional map of the current state of the room.
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|                 If provided then that map is used to check whether they are a
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|                 member of the room. Otherwise the current membership is
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|                 loaded from the database.
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|         Raises:
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|             AuthError if the user is not in the room.
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|         Returns:
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|             A deferred membership event for the user if the user is in
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|             the room.
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|         """
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|         if current_state:
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|             member = current_state.get(
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|                 (EventTypes.Member, user_id),
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|                 None
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|             )
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|         else:
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|             member = yield self.state.get_current_state(
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|                 room_id=room_id,
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|                 event_type=EventTypes.Member,
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|                 state_key=user_id
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|             )
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| 
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|         self._check_joined_room(member, user_id, room_id)
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|         defer.returnValue(member)
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| 
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|     @defer.inlineCallbacks
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|     def check_user_was_in_room(self, room_id, user_id):
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|         """Check if the user was in the room at some point.
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|         Args:
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|             room_id(str): The room to check.
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|             user_id(str): The user to check.
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|         Raises:
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|             AuthError if the user was never in the room.
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|         Returns:
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|             A deferred membership event for the user if the user was in the
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|             room. This will be the join event if they are currently joined to
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|             the room. This will be the leave event if they have left the room.
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|         """
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|         member = yield self.state.get_current_state(
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|             room_id=room_id,
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|             event_type=EventTypes.Member,
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|             state_key=user_id
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|         )
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|         membership = member.membership if member else None
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| 
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|         if membership not in (Membership.JOIN, Membership.LEAVE):
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|             raise AuthError(403, "User %s not in room %s" % (
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|                 user_id, room_id
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|             ))
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| 
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|         if membership == Membership.LEAVE:
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|             forgot = yield self.store.did_forget(user_id, room_id)
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|             if forgot:
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|                 raise AuthError(403, "User %s not in room %s" % (
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|                     user_id, room_id
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|                 ))
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| 
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|         defer.returnValue(member)
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| 
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|     @defer.inlineCallbacks
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|     def check_host_in_room(self, room_id, host):
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|         with Measure(self.clock, "check_host_in_room"):
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|             latest_event_ids = yield self.store.is_host_joined(room_id, host)
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|             defer.returnValue(latest_event_ids)
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| 
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|     def _check_joined_room(self, member, user_id, room_id):
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|         if not member or member.membership != Membership.JOIN:
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|             raise AuthError(403, "User %s not in room %s (%s)" % (
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|                 user_id, room_id, repr(member)
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|             ))
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| 
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|     def can_federate(self, event, auth_events):
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|         creation_event = auth_events.get((EventTypes.Create, ""))
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| 
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|         return creation_event.content.get("m.federate", True) is True
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| 
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|     def get_public_keys(self, invite_event):
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|         return event_auth.get_public_keys(invite_event)
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| 
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|     @defer.inlineCallbacks
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|     def get_user_by_req(self, request, allow_guest=False, rights="access"):
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|         """ Get a registered user's ID.
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| 
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|         Args:
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|             request - An HTTP request with an access_token query parameter.
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|         Returns:
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|             defer.Deferred: resolves to a ``synapse.types.Requester`` object
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|         Raises:
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|             AuthError if no user by that token exists or the token is invalid.
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|         """
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|         # Can optionally look elsewhere in the request (e.g. headers)
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|         try:
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|             ip_addr = self.hs.get_ip_from_request(request)
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|             user_agent = request.requestHeaders.getRawHeaders(
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|                 b"User-Agent",
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|                 default=[b""]
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|             )[0].decode('ascii', 'surrogateescape')
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| 
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|             access_token = self.get_access_token_from_request(
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|                 request, self.TOKEN_NOT_FOUND_HTTP_STATUS
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|             )
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| 
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|             user_id, app_service = yield self._get_appservice_user_id(request)
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|             if user_id:
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|                 request.authenticated_entity = user_id
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| 
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|                 if ip_addr and self.hs.config.track_appservice_user_ips:
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|                     yield self.store.insert_client_ip(
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|                         user_id=user_id,
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|                         access_token=access_token,
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|                         ip=ip_addr,
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|                         user_agent=user_agent,
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|                         device_id="dummy-device",  # stubbed
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|                     )
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| 
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|                 defer.returnValue(
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|                     synapse.types.create_requester(user_id, app_service=app_service)
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|                 )
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| 
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|             user_info = yield self.get_user_by_access_token(access_token, rights)
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|             user = user_info["user"]
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|             token_id = user_info["token_id"]
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|             is_guest = user_info["is_guest"]
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| 
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|             # device_id may not be present if get_user_by_access_token has been
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|             # stubbed out.
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|             device_id = user_info.get("device_id")
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| 
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|             if user and access_token and ip_addr:
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|                 yield self.store.insert_client_ip(
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|                     user_id=user.to_string(),
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|                     access_token=access_token,
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|                     ip=ip_addr,
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|                     user_agent=user_agent,
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|                     device_id=device_id,
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|                 )
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| 
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|             if is_guest and not allow_guest:
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|                 raise AuthError(
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|                     403, "Guest access not allowed", errcode=Codes.GUEST_ACCESS_FORBIDDEN
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|                 )
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| 
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|             request.authenticated_entity = user.to_string()
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| 
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|             defer.returnValue(synapse.types.create_requester(
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|                 user, token_id, is_guest, device_id, app_service=app_service)
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|             )
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|         except KeyError:
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|             raise AuthError(
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|                 self.TOKEN_NOT_FOUND_HTTP_STATUS, "Missing access token.",
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|                 errcode=Codes.MISSING_TOKEN
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|             )
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| 
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|     @defer.inlineCallbacks
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|     def _get_appservice_user_id(self, request):
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|         app_service = self.store.get_app_service_by_token(
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|             self.get_access_token_from_request(
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|                 request, self.TOKEN_NOT_FOUND_HTTP_STATUS
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|             )
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|         )
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|         if app_service is None:
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|             defer.returnValue((None, None))
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| 
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|         if app_service.ip_range_whitelist:
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|             ip_address = IPAddress(self.hs.get_ip_from_request(request))
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|             if ip_address not in app_service.ip_range_whitelist:
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|                 defer.returnValue((None, None))
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| 
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|         if b"user_id" not in request.args:
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|             defer.returnValue((app_service.sender, app_service))
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| 
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|         user_id = request.args[b"user_id"][0].decode('utf8')
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|         if app_service.sender == user_id:
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|             defer.returnValue((app_service.sender, app_service))
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| 
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|         if not app_service.is_interested_in_user(user_id):
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|             raise AuthError(
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|                 403,
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|                 "Application service cannot masquerade as this user."
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|             )
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|         if not (yield self.store.get_user_by_id(user_id)):
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|             raise AuthError(
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|                 403,
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|                 "Application service has not registered this user"
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|             )
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|         defer.returnValue((user_id, app_service))
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| 
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|     @defer.inlineCallbacks
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|     def get_user_by_access_token(self, token, rights="access"):
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|         """ Validate access token and get user_id from it
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| 
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|         Args:
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|             token (str): The access token to get the user by.
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|             rights (str): The operation being performed; the access token must
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|                 allow this.
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|         Returns:
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|             Deferred[dict]: dict that includes:
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|                `user` (UserID)
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|                `is_guest` (bool)
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|                `token_id` (int|None): access token id. May be None if guest
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|                `device_id` (str|None): device corresponding to access token
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|         Raises:
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|             AuthError if no user by that token exists or the token is invalid.
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|         """
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| 
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|         if rights == "access":
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|             # first look in the database
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|             r = yield self._look_up_user_by_access_token(token)
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|             if r:
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|                 defer.returnValue(r)
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| 
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|         # otherwise it needs to be a valid macaroon
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|         try:
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|             user_id, guest = self._parse_and_validate_macaroon(token, rights)
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|             user = UserID.from_string(user_id)
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| 
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|             if rights == "access":
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|                 if not guest:
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|                     # non-guest access tokens must be in the database
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|                     logger.warning("Unrecognised access token - not in store.")
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|                     raise AuthError(
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|                         self.TOKEN_NOT_FOUND_HTTP_STATUS,
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|                         "Unrecognised access token.",
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|                         errcode=Codes.UNKNOWN_TOKEN,
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|                     )
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| 
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|                 # Guest access tokens are not stored in the database (there can
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|                 # only be one access token per guest, anyway).
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|                 #
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|                 # In order to prevent guest access tokens being used as regular
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|                 # user access tokens (and hence getting around the invalidation
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|                 # process), we look up the user id and check that it is indeed
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|                 # a guest user.
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|                 #
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|                 # It would of course be much easier to store guest access
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|                 # tokens in the database as well, but that would break existing
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|                 # guest tokens.
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|                 stored_user = yield self.store.get_user_by_id(user_id)
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|                 if not stored_user:
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|                     raise AuthError(
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|                         self.TOKEN_NOT_FOUND_HTTP_STATUS,
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|                         "Unknown user_id %s" % user_id,
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|                         errcode=Codes.UNKNOWN_TOKEN
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|                     )
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|                 if not stored_user["is_guest"]:
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|                     raise AuthError(
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|                         self.TOKEN_NOT_FOUND_HTTP_STATUS,
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|                         "Guest access token used for regular user",
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|                         errcode=Codes.UNKNOWN_TOKEN
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|                     )
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|                 ret = {
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|                     "user": user,
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|                     "is_guest": True,
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|                     "token_id": None,
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|                     # all guests get the same device id
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|                     "device_id": GUEST_DEVICE_ID,
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|                 }
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|             elif rights == "delete_pusher":
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|                 # We don't store these tokens in the database
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|                 ret = {
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|                     "user": user,
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|                     "is_guest": False,
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|                     "token_id": None,
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|                     "device_id": None,
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|                 }
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|             else:
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|                 raise RuntimeError("Unknown rights setting %s", rights)
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|             defer.returnValue(ret)
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|         except (
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|             _InvalidMacaroonException,
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|             pymacaroons.exceptions.MacaroonException,
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|             TypeError,
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|             ValueError,
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|         ) as e:
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|             logger.warning("Invalid macaroon in auth: %s %s", type(e), e)
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|             raise AuthError(
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|                 self.TOKEN_NOT_FOUND_HTTP_STATUS, "Invalid macaroon passed.",
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|                 errcode=Codes.UNKNOWN_TOKEN
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|             )
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| 
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|     def _parse_and_validate_macaroon(self, token, rights="access"):
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|         """Takes a macaroon and tries to parse and validate it. This is cached
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|         if and only if rights == access and there isn't an expiry.
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| 
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|         On invalid macaroon raises _InvalidMacaroonException
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| 
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|         Returns:
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|             (user_id, is_guest)
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|         """
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|         if rights == "access":
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|             cached = self.token_cache.get(token, None)
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|             if cached:
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|                 return cached
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| 
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|         try:
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|             macaroon = pymacaroons.Macaroon.deserialize(token)
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|         except Exception:  # deserialize can throw more-or-less anything
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|             # doesn't look like a macaroon: treat it as an opaque token which
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|             # must be in the database.
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|             # TODO: it would be nice to get rid of this, but apparently some
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|             # people use access tokens which aren't macaroons
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|             raise _InvalidMacaroonException()
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| 
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|         try:
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|             user_id = self.get_user_id_from_macaroon(macaroon)
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| 
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|             has_expiry = False
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|             guest = False
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|             for caveat in macaroon.caveats:
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|                 if caveat.caveat_id.startswith("time "):
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|                     has_expiry = True
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|                 elif caveat.caveat_id == "guest = true":
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|                     guest = True
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| 
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|             self.validate_macaroon(
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|                 macaroon, rights, self.hs.config.expire_access_token,
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|                 user_id=user_id,
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|             )
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|         except (pymacaroons.exceptions.MacaroonException, TypeError, ValueError):
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|             raise AuthError(
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|                 self.TOKEN_NOT_FOUND_HTTP_STATUS, "Invalid macaroon passed.",
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|                 errcode=Codes.UNKNOWN_TOKEN
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|             )
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| 
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|         if not has_expiry and rights == "access":
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|             self.token_cache[token] = (user_id, guest)
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| 
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|         return user_id, guest
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| 
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|     def get_user_id_from_macaroon(self, macaroon):
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|         """Retrieve the user_id given by the caveats on the macaroon.
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| 
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|         Does *not* validate the macaroon.
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| 
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|         Args:
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|             macaroon (pymacaroons.Macaroon): The macaroon to validate
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| 
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|         Returns:
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|             (str) user id
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| 
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|         Raises:
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|             AuthError if there is no user_id caveat in the macaroon
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|         """
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|         user_prefix = "user_id = "
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|         for caveat in macaroon.caveats:
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|             if caveat.caveat_id.startswith(user_prefix):
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|                 return caveat.caveat_id[len(user_prefix):]
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|         raise AuthError(
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|             self.TOKEN_NOT_FOUND_HTTP_STATUS, "No user caveat in macaroon",
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|             errcode=Codes.UNKNOWN_TOKEN
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|         )
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| 
 | |
|     def validate_macaroon(self, macaroon, type_string, verify_expiry, user_id):
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|         """
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|         validate that a Macaroon is understood by and was signed by this server.
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| 
 | |
|         Args:
 | |
|             macaroon(pymacaroons.Macaroon): The macaroon to validate
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|             type_string(str): The kind of token required (e.g. "access",
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|                               "delete_pusher")
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|             verify_expiry(bool): Whether to verify whether the macaroon has expired.
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|             user_id (str): The user_id required
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|         """
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|         v = pymacaroons.Verifier()
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| 
 | |
|         # the verifier runs a test for every caveat on the macaroon, to check
 | |
|         # that it is met for the current request. Each caveat must match at
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|         # least one of the predicates specified by satisfy_exact or
 | |
|         # specify_general.
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|         v.satisfy_exact("gen = 1")
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|         v.satisfy_exact("type = " + type_string)
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|         v.satisfy_exact("user_id = %s" % user_id)
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|         v.satisfy_exact("guest = true")
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| 
 | |
|         # verify_expiry should really always be True, but there exist access
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|         # tokens in the wild which expire when they should not, so we can't
 | |
|         # enforce expiry yet (so we have to allow any caveat starting with
 | |
|         # 'time < ' in access tokens).
 | |
|         #
 | |
|         # On the other hand, short-term login tokens (as used by CAS login, for
 | |
|         # example) have an expiry time which we do want to enforce.
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| 
 | |
|         if verify_expiry:
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|             v.satisfy_general(self._verify_expiry)
 | |
|         else:
 | |
|             v.satisfy_general(lambda c: c.startswith("time < "))
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| 
 | |
|         # access_tokens include a nonce for uniqueness: any value is acceptable
 | |
|         v.satisfy_general(lambda c: c.startswith("nonce = "))
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| 
 | |
|         v.verify(macaroon, self.hs.config.macaroon_secret_key)
 | |
| 
 | |
|     def _verify_expiry(self, caveat):
 | |
|         prefix = "time < "
 | |
|         if not caveat.startswith(prefix):
 | |
|             return False
 | |
|         expiry = int(caveat[len(prefix):])
 | |
|         now = self.hs.get_clock().time_msec()
 | |
|         return now < expiry
 | |
| 
 | |
|     @defer.inlineCallbacks
 | |
|     def _look_up_user_by_access_token(self, token):
 | |
|         ret = yield self.store.get_user_by_access_token(token)
 | |
|         if not ret:
 | |
|             defer.returnValue(None)
 | |
| 
 | |
|         # we use ret.get() below because *lots* of unit tests stub out
 | |
|         # get_user_by_access_token in a way where it only returns a couple of
 | |
|         # the fields.
 | |
|         user_info = {
 | |
|             "user": UserID.from_string(ret.get("name")),
 | |
|             "token_id": ret.get("token_id", None),
 | |
|             "is_guest": False,
 | |
|             "device_id": ret.get("device_id"),
 | |
|         }
 | |
|         defer.returnValue(user_info)
 | |
| 
 | |
|     def get_appservice_by_req(self, request):
 | |
|         try:
 | |
|             token = self.get_access_token_from_request(
 | |
|                 request, self.TOKEN_NOT_FOUND_HTTP_STATUS
 | |
|             )
 | |
|             service = self.store.get_app_service_by_token(token)
 | |
|             if not service:
 | |
|                 logger.warn("Unrecognised appservice access token.")
 | |
|                 raise AuthError(
 | |
|                     self.TOKEN_NOT_FOUND_HTTP_STATUS,
 | |
|                     "Unrecognised access token.",
 | |
|                     errcode=Codes.UNKNOWN_TOKEN
 | |
|                 )
 | |
|             request.authenticated_entity = service.sender
 | |
|             return defer.succeed(service)
 | |
|         except KeyError:
 | |
|             raise AuthError(
 | |
|                 self.TOKEN_NOT_FOUND_HTTP_STATUS, "Missing access token."
 | |
|             )
 | |
| 
 | |
|     def is_server_admin(self, user):
 | |
|         """ Check if the given user is a local server admin.
 | |
| 
 | |
|         Args:
 | |
|             user (str): mxid of user to check
 | |
| 
 | |
|         Returns:
 | |
|             bool: True if the user is an admin
 | |
|         """
 | |
|         return self.store.is_server_admin(user)
 | |
| 
 | |
|     @defer.inlineCallbacks
 | |
|     def compute_auth_events(self, event, current_state_ids, for_verification=False):
 | |
|         if event.type == EventTypes.Create:
 | |
|             defer.returnValue([])
 | |
| 
 | |
|         auth_ids = []
 | |
| 
 | |
|         key = (EventTypes.PowerLevels, "", )
 | |
|         power_level_event_id = current_state_ids.get(key)
 | |
| 
 | |
|         if power_level_event_id:
 | |
|             auth_ids.append(power_level_event_id)
 | |
| 
 | |
|         key = (EventTypes.JoinRules, "", )
 | |
|         join_rule_event_id = current_state_ids.get(key)
 | |
| 
 | |
|         key = (EventTypes.Member, event.sender, )
 | |
|         member_event_id = current_state_ids.get(key)
 | |
| 
 | |
|         key = (EventTypes.Create, "", )
 | |
|         create_event_id = current_state_ids.get(key)
 | |
|         if create_event_id:
 | |
|             auth_ids.append(create_event_id)
 | |
| 
 | |
|         if join_rule_event_id:
 | |
|             join_rule_event = yield self.store.get_event(join_rule_event_id)
 | |
|             join_rule = join_rule_event.content.get("join_rule")
 | |
|             is_public = join_rule == JoinRules.PUBLIC if join_rule else False
 | |
|         else:
 | |
|             is_public = False
 | |
| 
 | |
|         if event.type == EventTypes.Member:
 | |
|             e_type = event.content["membership"]
 | |
|             if e_type in [Membership.JOIN, Membership.INVITE]:
 | |
|                 if join_rule_event_id:
 | |
|                     auth_ids.append(join_rule_event_id)
 | |
| 
 | |
|             if e_type == Membership.JOIN:
 | |
|                 if member_event_id and not is_public:
 | |
|                     auth_ids.append(member_event_id)
 | |
|             else:
 | |
|                 if member_event_id:
 | |
|                     auth_ids.append(member_event_id)
 | |
| 
 | |
|                 if for_verification:
 | |
|                     key = (EventTypes.Member, event.state_key, )
 | |
|                     existing_event_id = current_state_ids.get(key)
 | |
|                     if existing_event_id:
 | |
|                         auth_ids.append(existing_event_id)
 | |
| 
 | |
|             if e_type == Membership.INVITE:
 | |
|                 if "third_party_invite" in event.content:
 | |
|                     key = (
 | |
|                         EventTypes.ThirdPartyInvite,
 | |
|                         event.content["third_party_invite"]["signed"]["token"]
 | |
|                     )
 | |
|                     third_party_invite_id = current_state_ids.get(key)
 | |
|                     if third_party_invite_id:
 | |
|                         auth_ids.append(third_party_invite_id)
 | |
|         elif member_event_id:
 | |
|             member_event = yield self.store.get_event(member_event_id)
 | |
|             if member_event.content["membership"] == Membership.JOIN:
 | |
|                 auth_ids.append(member_event.event_id)
 | |
| 
 | |
|         defer.returnValue(auth_ids)
 | |
| 
 | |
|     def check_redaction(self, room_version, event, auth_events):
 | |
|         """Check whether the event sender is allowed to redact the target event.
 | |
| 
 | |
|         Returns:
 | |
|             True if the the sender is allowed to redact the target event if the
 | |
|             target event was created by them.
 | |
|             False if the sender is allowed to redact the target event with no
 | |
|             further checks.
 | |
| 
 | |
|         Raises:
 | |
|             AuthError if the event sender is definitely not allowed to redact
 | |
|             the target event.
 | |
|         """
 | |
|         return event_auth.check_redaction(room_version, event, auth_events)
 | |
| 
 | |
|     @defer.inlineCallbacks
 | |
|     def check_can_change_room_list(self, room_id, user):
 | |
|         """Check if the user is allowed to edit the room's entry in the
 | |
|         published room list.
 | |
| 
 | |
|         Args:
 | |
|             room_id (str)
 | |
|             user (UserID)
 | |
|         """
 | |
| 
 | |
|         is_admin = yield self.is_server_admin(user)
 | |
|         if is_admin:
 | |
|             defer.returnValue(True)
 | |
| 
 | |
|         user_id = user.to_string()
 | |
|         yield self.check_joined_room(room_id, user_id)
 | |
| 
 | |
|         # We currently require the user is a "moderator" in the room. We do this
 | |
|         # by checking if they would (theoretically) be able to change the
 | |
|         # m.room.aliases events
 | |
|         power_level_event = yield self.state.get_current_state(
 | |
|             room_id, EventTypes.PowerLevels, ""
 | |
|         )
 | |
| 
 | |
|         auth_events = {}
 | |
|         if power_level_event:
 | |
|             auth_events[(EventTypes.PowerLevels, "")] = power_level_event
 | |
| 
 | |
|         send_level = event_auth.get_send_level(
 | |
|             EventTypes.Aliases, "", power_level_event,
 | |
|         )
 | |
|         user_level = event_auth.get_user_power_level(user_id, auth_events)
 | |
| 
 | |
|         if user_level < send_level:
 | |
|             raise AuthError(
 | |
|                 403,
 | |
|                 "This server requires you to be a moderator in the room to"
 | |
|                 " edit its room list entry"
 | |
|             )
 | |
| 
 | |
|     @staticmethod
 | |
|     def has_access_token(request):
 | |
|         """Checks if the request has an access_token.
 | |
| 
 | |
|         Returns:
 | |
|             bool: False if no access_token was given, True otherwise.
 | |
|         """
 | |
|         query_params = request.args.get(b"access_token")
 | |
|         auth_headers = request.requestHeaders.getRawHeaders(b"Authorization")
 | |
|         return bool(query_params) or bool(auth_headers)
 | |
| 
 | |
|     @staticmethod
 | |
|     def get_access_token_from_request(request, token_not_found_http_status=401):
 | |
|         """Extracts the access_token from the request.
 | |
| 
 | |
|         Args:
 | |
|             request: The http request.
 | |
|             token_not_found_http_status(int): The HTTP status code to set in the
 | |
|                 AuthError if the token isn't found. This is used in some of the
 | |
|                 legacy APIs to change the status code to 403 from the default of
 | |
|                 401 since some of the old clients depended on auth errors returning
 | |
|                 403.
 | |
|         Returns:
 | |
|             unicode: The access_token
 | |
|         Raises:
 | |
|             AuthError: If there isn't an access_token in the request.
 | |
|         """
 | |
| 
 | |
|         auth_headers = request.requestHeaders.getRawHeaders(b"Authorization")
 | |
|         query_params = request.args.get(b"access_token")
 | |
|         if auth_headers:
 | |
|             # Try the get the access_token from a "Authorization: Bearer"
 | |
|             # header
 | |
|             if query_params is not None:
 | |
|                 raise AuthError(
 | |
|                     token_not_found_http_status,
 | |
|                     "Mixing Authorization headers and access_token query parameters.",
 | |
|                     errcode=Codes.MISSING_TOKEN,
 | |
|                 )
 | |
|             if len(auth_headers) > 1:
 | |
|                 raise AuthError(
 | |
|                     token_not_found_http_status,
 | |
|                     "Too many Authorization headers.",
 | |
|                     errcode=Codes.MISSING_TOKEN,
 | |
|                 )
 | |
|             parts = auth_headers[0].split(b" ")
 | |
|             if parts[0] == b"Bearer" and len(parts) == 2:
 | |
|                 return parts[1].decode('ascii')
 | |
|             else:
 | |
|                 raise AuthError(
 | |
|                     token_not_found_http_status,
 | |
|                     "Invalid Authorization header.",
 | |
|                     errcode=Codes.MISSING_TOKEN,
 | |
|                 )
 | |
|         else:
 | |
|             # Try to get the access_token from the query params.
 | |
|             if not query_params:
 | |
|                 raise AuthError(
 | |
|                     token_not_found_http_status,
 | |
|                     "Missing access token.",
 | |
|                     errcode=Codes.MISSING_TOKEN
 | |
|                 )
 | |
| 
 | |
|             return query_params[0].decode('ascii')
 | |
| 
 | |
|     @defer.inlineCallbacks
 | |
|     def check_in_room_or_world_readable(self, room_id, user_id):
 | |
|         """Checks that the user is or was in the room or the room is world
 | |
|         readable. If it isn't then an exception is raised.
 | |
| 
 | |
|         Returns:
 | |
|             Deferred[tuple[str, str|None]]: Resolves to the current membership of
 | |
|             the user in the room and the membership event ID of the user. If
 | |
|             the user is not in the room and never has been, then
 | |
|             `(Membership.JOIN, None)` is returned.
 | |
|         """
 | |
| 
 | |
|         try:
 | |
|             # check_user_was_in_room will return the most recent membership
 | |
|             # event for the user if:
 | |
|             #  * The user is a non-guest user, and was ever in the room
 | |
|             #  * The user is a guest user, and has joined the room
 | |
|             # else it will throw.
 | |
|             member_event = yield self.check_user_was_in_room(room_id, user_id)
 | |
|             defer.returnValue((member_event.membership, member_event.event_id))
 | |
|         except AuthError:
 | |
|             visibility = yield self.state.get_current_state(
 | |
|                 room_id, EventTypes.RoomHistoryVisibility, ""
 | |
|             )
 | |
|             if (
 | |
|                 visibility and
 | |
|                 visibility.content["history_visibility"] == "world_readable"
 | |
|             ):
 | |
|                 defer.returnValue((Membership.JOIN, None))
 | |
|                 return
 | |
|             raise AuthError(
 | |
|                 403, "Guest access not allowed", errcode=Codes.GUEST_ACCESS_FORBIDDEN
 | |
|             )
 | |
| 
 | |
|     @defer.inlineCallbacks
 | |
|     def check_auth_blocking(self, user_id=None, threepid=None):
 | |
|         """Checks if the user should be rejected for some external reason,
 | |
|         such as monthly active user limiting or global disable flag
 | |
| 
 | |
|         Args:
 | |
|             user_id(str|None): If present, checks for presence against existing
 | |
|             MAU cohort
 | |
| 
 | |
|             threepid(dict|None): If present, checks for presence against configured
 | |
|             reserved threepid. Used in cases where the user is trying register
 | |
|             with a MAU blocked server, normally they would be rejected but their
 | |
|             threepid is on the reserved list. user_id and
 | |
|             threepid should never be set at the same time.
 | |
|         """
 | |
| 
 | |
|         # Never fail an auth check for the server notices users or support user
 | |
|         # This can be a problem where event creation is prohibited due to blocking
 | |
|         if user_id is not None:
 | |
|             if user_id == self.hs.config.server_notices_mxid:
 | |
|                 return
 | |
|             if (yield self.store.is_support_user(user_id)):
 | |
|                 return
 | |
| 
 | |
|         if self.hs.config.hs_disabled:
 | |
|             raise ResourceLimitError(
 | |
|                 403, self.hs.config.hs_disabled_message,
 | |
|                 errcode=Codes.RESOURCE_LIMIT_EXCEEDED,
 | |
|                 admin_contact=self.hs.config.admin_contact,
 | |
|                 limit_type=self.hs.config.hs_disabled_limit_type
 | |
|             )
 | |
|         if self.hs.config.limit_usage_by_mau is True:
 | |
|             assert not (user_id and threepid)
 | |
| 
 | |
|             # If the user is already part of the MAU cohort or a trial user
 | |
|             if user_id:
 | |
|                 timestamp = yield self.store.user_last_seen_monthly_active(user_id)
 | |
|                 if timestamp:
 | |
|                     return
 | |
| 
 | |
|                 is_trial = yield self.store.is_trial_user(user_id)
 | |
|                 if is_trial:
 | |
|                     return
 | |
|             elif threepid:
 | |
|                 # If the user does not exist yet, but is signing up with a
 | |
|                 # reserved threepid then pass auth check
 | |
|                 if is_threepid_reserved(
 | |
|                     self.hs.config.mau_limits_reserved_threepids, threepid
 | |
|                 ):
 | |
|                     return
 | |
|             # Else if there is no room in the MAU bucket, bail
 | |
|             current_mau = yield self.store.get_monthly_active_count()
 | |
|             if current_mau >= self.hs.config.max_mau_value:
 | |
|                 raise ResourceLimitError(
 | |
|                     403, "Monthly Active User Limit Exceeded",
 | |
|                     admin_contact=self.hs.config.admin_contact,
 | |
|                     errcode=Codes.RESOURCE_LIMIT_EXCEEDED,
 | |
|                     limit_type="monthly_active_user"
 | |
|                 )
 |