584 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			Python
		
	
	
			
		
		
	
	
			584 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			Python
		
	
	
| # -*- coding: utf-8 -*-
 | |
| # Copyright 2014, 2015 OpenMarket Ltd
 | |
| #
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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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| 
 | |
| """This module contains classes for authenticating the user."""
 | |
| 
 | |
| from twisted.internet import defer
 | |
| 
 | |
| from synapse.api.constants import EventTypes, Membership, JoinRules
 | |
| from synapse.api.errors import AuthError, StoreError, Codes, SynapseError
 | |
| from synapse.util.logutils import log_function
 | |
| from synapse.util.async import run_on_reactor
 | |
| from synapse.types import UserID, ClientInfo
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| 
 | |
| import logging
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| 
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| logger = logging.getLogger(__name__)
 | |
| 
 | |
| 
 | |
| class Auth(object):
 | |
| 
 | |
|     def __init__(self, hs):
 | |
|         self.hs = hs
 | |
|         self.store = hs.get_datastore()
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|         self.state = hs.get_state_handler()
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| 
 | |
|     def check(self, event, auth_events):
 | |
|         """ Checks if this event is correctly authed.
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| 
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|         Returns:
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|             True if the auth checks pass.
 | |
|         """
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|         try:
 | |
|             if not hasattr(event, "room_id"):
 | |
|                 raise AuthError(500, "Event has no room_id: %s" % event)
 | |
|             if auth_events is None:
 | |
|                 # Oh, we don't know what the state of the room was, so we
 | |
|                 # are trusting that this is allowed (at least for now)
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|                 logger.warn("Trusting event: %s", event.event_id)
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|                 return True
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| 
 | |
|             if event.type == EventTypes.Create:
 | |
|                 # FIXME
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|                 return True
 | |
| 
 | |
|             # FIXME: Temp hack
 | |
|             if event.type == EventTypes.Aliases:
 | |
|                 return True
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| 
 | |
|             logger.debug("Auth events: %s", auth_events)
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| 
 | |
|             if event.type == EventTypes.Member:
 | |
|                 allowed = self.is_membership_change_allowed(
 | |
|                     event, auth_events
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|                 )
 | |
|                 if allowed:
 | |
|                     logger.debug("Allowing! %s", event)
 | |
|                 else:
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|                     logger.debug("Denying! %s", event)
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|                 return allowed
 | |
| 
 | |
|             self.check_event_sender_in_room(event, auth_events)
 | |
|             self._can_send_event(event, auth_events)
 | |
| 
 | |
|             if event.type == EventTypes.PowerLevels:
 | |
|                 self._check_power_levels(event, auth_events)
 | |
| 
 | |
|             if event.type == EventTypes.Redaction:
 | |
|                 self._check_redaction(event, auth_events)
 | |
| 
 | |
|             logger.debug("Allowing! %s", event)
 | |
|         except AuthError as e:
 | |
|             logger.info(
 | |
|                 "Event auth check failed on event %s with msg: %s",
 | |
|                 event, e.msg
 | |
|             )
 | |
|             logger.info("Denying! %s", event)
 | |
|             raise
 | |
| 
 | |
|     @defer.inlineCallbacks
 | |
|     def check_joined_room(self, room_id, user_id):
 | |
|         member = yield self.state.get_current_state(
 | |
|             room_id=room_id,
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|             event_type=EventTypes.Member,
 | |
|             state_key=user_id
 | |
|         )
 | |
|         self._check_joined_room(member, user_id, room_id)
 | |
|         defer.returnValue(member)
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| 
 | |
|     @defer.inlineCallbacks
 | |
|     def check_host_in_room(self, room_id, host):
 | |
|         curr_state = yield self.state.get_current_state(room_id)
 | |
| 
 | |
|         for event in curr_state:
 | |
|             if event.type == EventTypes.Member:
 | |
|                 try:
 | |
|                     if UserID.from_string(event.state_key).domain != host:
 | |
|                         continue
 | |
|                 except:
 | |
|                     logger.warn("state_key not user_id: %s", event.state_key)
 | |
|                     continue
 | |
| 
 | |
|                 if event.content["membership"] == Membership.JOIN:
 | |
|                     defer.returnValue(True)
 | |
| 
 | |
|         defer.returnValue(False)
 | |
| 
 | |
|     def check_event_sender_in_room(self, event, auth_events):
 | |
|         key = (EventTypes.Member, event.user_id, )
 | |
|         member_event = auth_events.get(key)
 | |
| 
 | |
|         return self._check_joined_room(
 | |
|             member_event,
 | |
|             event.user_id,
 | |
|             event.room_id
 | |
|         )
 | |
| 
 | |
|     def _check_joined_room(self, member, user_id, room_id):
 | |
|         if not member or member.membership != Membership.JOIN:
 | |
|             raise AuthError(403, "User %s not in room %s (%s)" % (
 | |
|                 user_id, room_id, repr(member)
 | |
|             ))
 | |
| 
 | |
|     @log_function
 | |
|     def is_membership_change_allowed(self, event, auth_events):
 | |
|         membership = event.content["membership"]
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| 
 | |
|         # Check if this is the room creator joining:
 | |
|         if len(event.prev_events) == 1 and Membership.JOIN == membership:
 | |
|             # Get room creation event:
 | |
|             key = (EventTypes.Create, "", )
 | |
|             create = auth_events.get(key)
 | |
|             if create and event.prev_events[0][0] == create.event_id:
 | |
|                 if create.content["creator"] == event.state_key:
 | |
|                     return True
 | |
| 
 | |
|         target_user_id = event.state_key
 | |
| 
 | |
|         # get info about the caller
 | |
|         key = (EventTypes.Member, event.user_id, )
 | |
|         caller = auth_events.get(key)
 | |
| 
 | |
|         caller_in_room = caller and caller.membership == Membership.JOIN
 | |
|         caller_invited = caller and caller.membership == Membership.INVITE
 | |
| 
 | |
|         # get info about the target
 | |
|         key = (EventTypes.Member, target_user_id, )
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|         target = auth_events.get(key)
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| 
 | |
|         target_in_room = target and target.membership == Membership.JOIN
 | |
| 
 | |
|         key = (EventTypes.JoinRules, "", )
 | |
|         join_rule_event = auth_events.get(key)
 | |
|         if join_rule_event:
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|             join_rule = join_rule_event.content.get(
 | |
|                 "join_rule", JoinRules.INVITE
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|             )
 | |
|         else:
 | |
|             join_rule = JoinRules.INVITE
 | |
| 
 | |
|         user_level = self._get_power_level_from_event_state(
 | |
|             event,
 | |
|             event.user_id,
 | |
|             auth_events,
 | |
|         )
 | |
| 
 | |
|         ban_level, kick_level, redact_level = (
 | |
|             self._get_ops_level_from_event_state(
 | |
|                 event,
 | |
|                 auth_events,
 | |
|             )
 | |
|         )
 | |
| 
 | |
|         logger.debug(
 | |
|             "is_membership_change_allowed: %s",
 | |
|             {
 | |
|                 "caller_in_room": caller_in_room,
 | |
|                 "caller_invited": caller_invited,
 | |
|                 "target_in_room": target_in_room,
 | |
|                 "membership": membership,
 | |
|                 "join_rule": join_rule,
 | |
|                 "target_user_id": target_user_id,
 | |
|                 "event.user_id": event.user_id,
 | |
|             }
 | |
|         )
 | |
| 
 | |
|         if Membership.INVITE == membership:
 | |
|             # TODO (erikj): We should probably handle this more intelligently
 | |
|             # PRIVATE join rules.
 | |
| 
 | |
|             # Invites are valid iff caller is in the room and target isn't.
 | |
|             if not caller_in_room:  # caller isn't joined
 | |
|                 raise AuthError(
 | |
|                     403,
 | |
|                     "%s not in room %s." % (event.user_id, event.room_id,)
 | |
|                 )
 | |
|             elif target_in_room:  # the target is already in the room.
 | |
|                 raise AuthError(403, "%s is already in the room." %
 | |
|                                      target_user_id)
 | |
|         elif Membership.JOIN == membership:
 | |
|             # Joins are valid iff caller == target and they were:
 | |
|             # invited: They are accepting the invitation
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|             # joined: It's a NOOP
 | |
|             if event.user_id != target_user_id:
 | |
|                 raise AuthError(403, "Cannot force another user to join.")
 | |
|             elif join_rule == JoinRules.PUBLIC:
 | |
|                 pass
 | |
|             elif join_rule == JoinRules.INVITE:
 | |
|                 if not caller_in_room and not caller_invited:
 | |
|                     raise AuthError(403, "You are not invited to this room.")
 | |
|             else:
 | |
|                 # TODO (erikj): may_join list
 | |
|                 # TODO (erikj): private rooms
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|                 raise AuthError(403, "You are not allowed to join this room")
 | |
|         elif Membership.LEAVE == membership:
 | |
|             # TODO (erikj): Implement kicks.
 | |
| 
 | |
|             if not caller_in_room:  # trying to leave a room you aren't joined
 | |
|                 raise AuthError(
 | |
|                     403,
 | |
|                     "%s not in room %s." % (target_user_id, event.room_id,)
 | |
|                 )
 | |
|             elif target_user_id != event.user_id:
 | |
|                 if kick_level:
 | |
|                     kick_level = int(kick_level)
 | |
|                 else:
 | |
|                     kick_level = 50  # FIXME (erikj): What should we do here?
 | |
| 
 | |
|                 if user_level < kick_level:
 | |
|                     raise AuthError(
 | |
|                         403, "You cannot kick user %s." % target_user_id
 | |
|                     )
 | |
|         elif Membership.BAN == membership:
 | |
|             if ban_level:
 | |
|                 ban_level = int(ban_level)
 | |
|             else:
 | |
|                 ban_level = 50  # FIXME (erikj): What should we do here?
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| 
 | |
|             if user_level < ban_level:
 | |
|                 raise AuthError(403, "You don't have permission to ban")
 | |
|         else:
 | |
|             raise AuthError(500, "Unknown membership %s" % membership)
 | |
| 
 | |
|         return True
 | |
| 
 | |
|     def _get_power_level_from_event_state(self, event, user_id, auth_events):
 | |
|         key = (EventTypes.PowerLevels, "", )
 | |
|         power_level_event = auth_events.get(key)
 | |
|         level = None
 | |
|         if power_level_event:
 | |
|             level = power_level_event.content.get("users", {}).get(user_id)
 | |
|             if not level:
 | |
|                 level = power_level_event.content.get("users_default", 0)
 | |
|         else:
 | |
|             key = (EventTypes.Create, "", )
 | |
|             create_event = auth_events.get(key)
 | |
|             if (create_event is not None and
 | |
|                     create_event.content["creator"] == user_id):
 | |
|                 return 100
 | |
| 
 | |
|         return level
 | |
| 
 | |
|     def _get_ops_level_from_event_state(self, event, auth_events):
 | |
|         key = (EventTypes.PowerLevels, "", )
 | |
|         power_level_event = auth_events.get(key)
 | |
| 
 | |
|         if power_level_event:
 | |
|             return (
 | |
|                 power_level_event.content.get("ban", 50),
 | |
|                 power_level_event.content.get("kick", 50),
 | |
|                 power_level_event.content.get("redact", 50),
 | |
|             )
 | |
|         return None, None, None,
 | |
| 
 | |
|     @defer.inlineCallbacks
 | |
|     def get_user_by_req(self, request):
 | |
|         """ Get a registered user's ID.
 | |
| 
 | |
|         Args:
 | |
|             request - An HTTP request with an access_token query parameter.
 | |
|         Returns:
 | |
|             tuple : of UserID and device string:
 | |
|                 User ID object of the user making the request
 | |
|                 Client ID object of the client instance the user is using
 | |
|         Raises:
 | |
|             AuthError if no user by that token exists or the token is invalid.
 | |
|         """
 | |
|         # Can optionally look elsewhere in the request (e.g. headers)
 | |
|         try:
 | |
|             access_token = request.args["access_token"][0]
 | |
|             user_info = yield self.get_user_by_token(access_token)
 | |
|             user = user_info["user"]
 | |
|             device_id = user_info["device_id"]
 | |
|             token_id = user_info["token_id"]
 | |
| 
 | |
|             ip_addr = self.hs.get_ip_from_request(request)
 | |
|             user_agent = request.requestHeaders.getRawHeaders(
 | |
|                 "User-Agent",
 | |
|                 default=[""]
 | |
|             )[0]
 | |
|             if user and access_token and ip_addr:
 | |
|                 yield self.store.insert_client_ip(
 | |
|                     user=user,
 | |
|                     access_token=access_token,
 | |
|                     device_id=user_info["device_id"],
 | |
|                     ip=ip_addr,
 | |
|                     user_agent=user_agent
 | |
|                 )
 | |
| 
 | |
|             defer.returnValue((user, ClientInfo(device_id, token_id)))
 | |
|         except KeyError:
 | |
|             raise AuthError(403, "Missing access token.")
 | |
| 
 | |
|     @defer.inlineCallbacks
 | |
|     def get_user_by_token(self, token):
 | |
|         """ Get a registered user's ID.
 | |
| 
 | |
|         Args:
 | |
|             token (str): The access token to get the user by.
 | |
|         Returns:
 | |
|             dict : dict that includes the user, device_id, and whether the
 | |
|                 user is a server admin.
 | |
|         Raises:
 | |
|             AuthError if no user by that token exists or the token is invalid.
 | |
|         """
 | |
|         try:
 | |
|             ret = yield self.store.get_user_by_token(token=token)
 | |
|             if not ret:
 | |
|                 raise StoreError()
 | |
| 
 | |
|             user_info = {
 | |
|                 "admin": bool(ret.get("admin", False)),
 | |
|                 "device_id": ret.get("device_id"),
 | |
|                 "user": UserID.from_string(ret.get("name")),
 | |
|                 "token_id": ret.get("token_id", None),
 | |
|             }
 | |
| 
 | |
|             defer.returnValue(user_info)
 | |
|         except StoreError:
 | |
|             raise AuthError(403, "Unrecognised access token.",
 | |
|                             errcode=Codes.UNKNOWN_TOKEN)
 | |
| 
 | |
|     def is_server_admin(self, user):
 | |
|         return self.store.is_server_admin(user)
 | |
| 
 | |
|     @defer.inlineCallbacks
 | |
|     def add_auth_events(self, builder, context):
 | |
|         yield run_on_reactor()
 | |
| 
 | |
|         auth_ids = self.compute_auth_events(builder, context.current_state)
 | |
| 
 | |
|         auth_events_entries = yield self.store.add_event_hashes(
 | |
|             auth_ids
 | |
|         )
 | |
| 
 | |
|         builder.auth_events = auth_events_entries
 | |
| 
 | |
|         context.auth_events = {
 | |
|             k: v
 | |
|             for k, v in context.current_state.items()
 | |
|             if v.event_id in auth_ids
 | |
|         }
 | |
| 
 | |
|     def compute_auth_events(self, event, current_state):
 | |
|         if event.type == EventTypes.Create:
 | |
|             return []
 | |
| 
 | |
|         auth_ids = []
 | |
| 
 | |
|         key = (EventTypes.PowerLevels, "", )
 | |
|         power_level_event = current_state.get(key)
 | |
| 
 | |
|         if power_level_event:
 | |
|             auth_ids.append(power_level_event.event_id)
 | |
| 
 | |
|         key = (EventTypes.JoinRules, "", )
 | |
|         join_rule_event = current_state.get(key)
 | |
| 
 | |
|         key = (EventTypes.Member, event.user_id, )
 | |
|         member_event = current_state.get(key)
 | |
| 
 | |
|         key = (EventTypes.Create, "", )
 | |
|         create_event = current_state.get(key)
 | |
|         if create_event:
 | |
|             auth_ids.append(create_event.event_id)
 | |
| 
 | |
|         if join_rule_event:
 | |
|             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:
 | |
|                     auth_ids.append(join_rule_event.event_id)
 | |
| 
 | |
|             if e_type == Membership.JOIN:
 | |
|                 if member_event and not is_public:
 | |
|                     auth_ids.append(member_event.event_id)
 | |
|             else:
 | |
|                 if member_event:
 | |
|                     auth_ids.append(member_event.event_id)
 | |
|         elif member_event:
 | |
|             if member_event.content["membership"] == Membership.JOIN:
 | |
|                 auth_ids.append(member_event.event_id)
 | |
| 
 | |
|         return auth_ids
 | |
| 
 | |
|     @log_function
 | |
|     def _can_send_event(self, event, auth_events):
 | |
|         key = (EventTypes.PowerLevels, "", )
 | |
|         send_level_event = auth_events.get(key)
 | |
|         send_level = None
 | |
|         if send_level_event:
 | |
|             send_level = send_level_event.content.get("events", {}).get(
 | |
|                 event.type
 | |
|             )
 | |
|             if not send_level:
 | |
|                 if hasattr(event, "state_key"):
 | |
|                     send_level = send_level_event.content.get(
 | |
|                         "state_default", 50
 | |
|                     )
 | |
|                 else:
 | |
|                     send_level = send_level_event.content.get(
 | |
|                         "events_default", 0
 | |
|                     )
 | |
| 
 | |
|         if send_level:
 | |
|             send_level = int(send_level)
 | |
|         else:
 | |
|             send_level = 0
 | |
| 
 | |
|         user_level = self._get_power_level_from_event_state(
 | |
|             event,
 | |
|             event.user_id,
 | |
|             auth_events,
 | |
|         )
 | |
| 
 | |
|         if user_level:
 | |
|             user_level = int(user_level)
 | |
|         else:
 | |
|             user_level = 0
 | |
| 
 | |
|         if user_level < send_level:
 | |
|             raise AuthError(
 | |
|                 403,
 | |
|                 "You don't have permission to post that to the room. " +
 | |
|                 "user_level (%d) < send_level (%d)" % (user_level, send_level)
 | |
|             )
 | |
| 
 | |
|         # Check state_key
 | |
|         if hasattr(event, "state_key"):
 | |
|             if not event.state_key.startswith("_"):
 | |
|                 if event.state_key.startswith("@"):
 | |
|                     if event.state_key != event.user_id:
 | |
|                         raise AuthError(
 | |
|                             403,
 | |
|                             "You are not allowed to set others state"
 | |
|                         )
 | |
|                     else:
 | |
|                         sender_domain = UserID.from_string(
 | |
|                             event.user_id
 | |
|                         ).domain
 | |
| 
 | |
|                         if sender_domain != event.state_key:
 | |
|                             raise AuthError(
 | |
|                                 403,
 | |
|                                 "You are not allowed to set others state"
 | |
|                             )
 | |
| 
 | |
|         return True
 | |
| 
 | |
|     def _check_redaction(self, event, auth_events):
 | |
|         user_level = self._get_power_level_from_event_state(
 | |
|             event,
 | |
|             event.user_id,
 | |
|             auth_events,
 | |
|         )
 | |
| 
 | |
|         _, _, redact_level = self._get_ops_level_from_event_state(
 | |
|             event,
 | |
|             auth_events,
 | |
|         )
 | |
| 
 | |
|         if user_level < redact_level:
 | |
|             raise AuthError(
 | |
|                 403,
 | |
|                 "You don't have permission to redact events"
 | |
|             )
 | |
| 
 | |
|     def _check_power_levels(self, event, auth_events):
 | |
|         user_list = event.content.get("users", {})
 | |
|         # Validate users
 | |
|         for k, v in user_list.items():
 | |
|             try:
 | |
|                 UserID.from_string(k)
 | |
|             except:
 | |
|                 raise SynapseError(400, "Not a valid user_id: %s" % (k,))
 | |
| 
 | |
|             try:
 | |
|                 int(v)
 | |
|             except:
 | |
|                 raise SynapseError(400, "Not a valid power level: %s" % (v,))
 | |
| 
 | |
|         key = (event.type, event.state_key, )
 | |
|         current_state = auth_events.get(key)
 | |
| 
 | |
|         if not current_state:
 | |
|             return
 | |
| 
 | |
|         user_level = self._get_power_level_from_event_state(
 | |
|             event,
 | |
|             event.user_id,
 | |
|             auth_events,
 | |
|         )
 | |
| 
 | |
|         # Check other levels:
 | |
|         levels_to_check = [
 | |
|             ("users_default", []),
 | |
|             ("events_default", []),
 | |
|             ("ban", []),
 | |
|             ("redact", []),
 | |
|             ("kick", []),
 | |
|         ]
 | |
| 
 | |
|         old_list = current_state.content.get("users")
 | |
|         for user in set(old_list.keys() + user_list.keys()):
 | |
|             levels_to_check.append(
 | |
|                 (user, ["users"])
 | |
|             )
 | |
| 
 | |
|         old_list = current_state.content.get("events")
 | |
|         new_list = event.content.get("events")
 | |
|         for ev_id in set(old_list.keys() + new_list.keys()):
 | |
|             levels_to_check.append(
 | |
|                 (ev_id, ["events"])
 | |
|             )
 | |
| 
 | |
|         old_state = current_state.content
 | |
|         new_state = event.content
 | |
| 
 | |
|         for level_to_check, dir in levels_to_check:
 | |
|             old_loc = old_state
 | |
|             for d in dir:
 | |
|                 old_loc = old_loc.get(d, {})
 | |
| 
 | |
|             new_loc = new_state
 | |
|             for d in dir:
 | |
|                 new_loc = new_loc.get(d, {})
 | |
| 
 | |
|             if level_to_check in old_loc:
 | |
|                 old_level = int(old_loc[level_to_check])
 | |
|             else:
 | |
|                 old_level = None
 | |
| 
 | |
|             if level_to_check in new_loc:
 | |
|                 new_level = int(new_loc[level_to_check])
 | |
|             else:
 | |
|                 new_level = None
 | |
| 
 | |
|             if new_level is not None and old_level is not None:
 | |
|                 if new_level == old_level:
 | |
|                     continue
 | |
| 
 | |
|             if old_level > user_level or new_level > user_level:
 | |
|                 raise AuthError(
 | |
|                     403,
 | |
|                     "You don't have permission to add ops level greater "
 | |
|                     "than your own"
 | |
|                 )
 |