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Diffstat (limited to 'synapse/handlers/room_member.py')
| -rw-r--r-- | synapse/handlers/room_member.py | 646 |
1 files changed, 646 insertions, 0 deletions
diff --git a/synapse/handlers/room_member.py b/synapse/handlers/room_member.py new file mode 100644 index 0000000000..01f833c371 --- /dev/null +++ b/synapse/handlers/room_member.py @@ -0,0 +1,646 @@ +# -*- coding: utf-8 -*- +# Copyright 2016 OpenMarket Ltd +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + + +from twisted.internet import defer + +from ._base import BaseHandler + +from synapse.types import UserID, RoomID, Requester +from synapse.api.constants import ( + EventTypes, Membership, +) +from synapse.api.errors import AuthError, SynapseError, Codes +from synapse.util.logcontext import preserve_context_over_fn + +from signedjson.sign import verify_signed_json +from signedjson.key import decode_verify_key_bytes + +from unpaddedbase64 import decode_base64 + +import logging + +logger = logging.getLogger(__name__) + +id_server_scheme = "https://" + + +def user_left_room(distributor, user, room_id): + return preserve_context_over_fn( + distributor.fire, + "user_left_room", user=user, room_id=room_id + ) + + +def user_joined_room(distributor, user, room_id): + return preserve_context_over_fn( + distributor.fire, + "user_joined_room", user=user, room_id=room_id + ) + + +class RoomMemberHandler(BaseHandler): + # TODO(paul): This handler currently contains a messy conflation of + # low-level API that works on UserID objects and so on, and REST-level + # API that takes ID strings and returns pagination chunks. These concerns + # ought to be separated out a lot better. + + def __init__(self, hs): + super(RoomMemberHandler, self).__init__(hs) + + self.clock = hs.get_clock() + + self.distributor = hs.get_distributor() + self.distributor.declare("user_joined_room") + self.distributor.declare("user_left_room") + + @defer.inlineCallbacks + def get_room_members(self, room_id): + users = yield self.store.get_users_in_room(room_id) + + defer.returnValue([UserID.from_string(u) for u in users]) + + @defer.inlineCallbacks + def fetch_room_distributions_into(self, room_id, localusers=None, + remotedomains=None, ignore_user=None): + """Fetch the distribution of a room, adding elements to either + 'localusers' or 'remotedomains', which should be a set() if supplied. + If ignore_user is set, ignore that user. + + This function returns nothing; its result is performed by the + side-effect on the two passed sets. This allows easy accumulation of + member lists of multiple rooms at once if required. + """ + members = yield self.get_room_members(room_id) + for member in members: + if ignore_user is not None and member == ignore_user: + continue + + if self.hs.is_mine(member): + if localusers is not None: + localusers.add(member) + else: + if remotedomains is not None: + remotedomains.add(member.domain) + + @defer.inlineCallbacks + def update_membership( + self, + requester, + target, + room_id, + action, + txn_id=None, + remote_room_hosts=None, + third_party_signed=None, + ratelimit=True, + ): + effective_membership_state = action + if action in ["kick", "unban"]: + effective_membership_state = "leave" + + if third_party_signed is not None: + replication = self.hs.get_replication_layer() + yield replication.exchange_third_party_invite( + third_party_signed["sender"], + target.to_string(), + room_id, + third_party_signed, + ) + + msg_handler = self.hs.get_handlers().message_handler + + content = {"membership": effective_membership_state} + if requester.is_guest: + content["kind"] = "guest" + + event, context = yield msg_handler.create_event( + { + "type": EventTypes.Member, + "content": content, + "room_id": room_id, + "sender": requester.user.to_string(), + "state_key": target.to_string(), + + # For backwards compatibility: + "membership": effective_membership_state, + }, + token_id=requester.access_token_id, + txn_id=txn_id, + ) + + old_state = context.current_state.get((EventTypes.Member, event.state_key)) + old_membership = old_state.content.get("membership") if old_state else None + if action == "unban" and old_membership != "ban": + raise SynapseError( + 403, + "Cannot unban user who was not banned (membership=%s)" % old_membership, + errcode=Codes.BAD_STATE + ) + if old_membership == "ban" and action != "unban": + raise SynapseError( + 403, + "Cannot %s user who was is banned" % (action,), + errcode=Codes.BAD_STATE + ) + + member_handler = self.hs.get_handlers().room_member_handler + yield member_handler.send_membership_event( + requester, + event, + context, + ratelimit=ratelimit, + remote_room_hosts=remote_room_hosts, + ) + + @defer.inlineCallbacks + def send_membership_event( + self, + requester, + event, + context, + remote_room_hosts=None, + ratelimit=True, + ): + """ + Change the membership status of a user in a room. + + Args: + requester (Requester): The local user who requested the membership + event. If None, certain checks, like whether this homeserver can + act as the sender, will be skipped. + event (SynapseEvent): The membership event. + context: The context of the event. + is_guest (bool): Whether the sender is a guest. + room_hosts ([str]): Homeservers which are likely to already be in + the room, and could be danced with in order to join this + homeserver for the first time. + ratelimit (bool): Whether to rate limit this request. + Raises: + SynapseError if there was a problem changing the membership. + """ + remote_room_hosts = remote_room_hosts or [] + + target_user = UserID.from_string(event.state_key) + room_id = event.room_id + + if requester is not None: + sender = UserID.from_string(event.sender) + assert sender == requester.user, ( + "Sender (%s) must be same as requester (%s)" % + (sender, requester.user) + ) + assert self.hs.is_mine(sender), "Sender must be our own: %s" % (sender,) + else: + requester = Requester(target_user, None, False) + + message_handler = self.hs.get_handlers().message_handler + prev_event = message_handler.deduplicate_state_event(event, context) + if prev_event is not None: + return + + action = "send" + + if event.membership == Membership.JOIN: + if requester.is_guest and not self._can_guest_join(context.current_state): + # This should be an auth check, but guests are a local concept, + # so don't really fit into the general auth process. + raise AuthError(403, "Guest access not allowed") + do_remote_join_dance, remote_room_hosts = self._should_do_dance( + context, + (self.get_inviter(event.state_key, context.current_state)), + remote_room_hosts, + ) + if do_remote_join_dance: + action = "remote_join" + elif event.membership == Membership.LEAVE: + is_host_in_room = self.is_host_in_room(context.current_state) + + if not is_host_in_room: + # perhaps we've been invited + inviter = self.get_inviter( + target_user.to_string(), context.current_state + ) + if not inviter: + raise SynapseError(404, "Not a known room") + + if self.hs.is_mine(inviter): + # the inviter was on our server, but has now left. Carry on + # with the normal rejection codepath. + # + # This is a bit of a hack, because the room might still be + # active on other servers. + pass + else: + # send the rejection to the inviter's HS. + remote_room_hosts = remote_room_hosts + [inviter.domain] + action = "remote_reject" + + federation_handler = self.hs.get_handlers().federation_handler + + if action == "remote_join": + if len(remote_room_hosts) == 0: + raise SynapseError(404, "No known servers") + + # We don't do an auth check if we are doing an invite + # join dance for now, since we're kinda implicitly checking + # that we are allowed to join when we decide whether or not we + # need to do the invite/join dance. + yield federation_handler.do_invite_join( + remote_room_hosts, + event.room_id, + event.user_id, + event.content, + ) + elif action == "remote_reject": + yield federation_handler.do_remotely_reject_invite( + remote_room_hosts, + room_id, + event.user_id + ) + else: + yield self.handle_new_client_event( + requester, + event, + context, + extra_users=[target_user], + ratelimit=ratelimit, + ) + + prev_member_event = context.current_state.get( + (EventTypes.Member, target_user.to_string()), + None + ) + + if event.membership == Membership.JOIN: + if not prev_member_event or prev_member_event.membership != Membership.JOIN: + # Only fire user_joined_room if the user has acutally joined the + # room. Don't bother if the user is just changing their profile + # info. + yield user_joined_room(self.distributor, target_user, room_id) + elif event.membership == Membership.LEAVE: + if prev_member_event and prev_member_event.membership == Membership.JOIN: + user_left_room(self.distributor, target_user, room_id) + + def _can_guest_join(self, current_state): + """ + Returns whether a guest can join a room based on its current state. + """ + guest_access = current_state.get((EventTypes.GuestAccess, ""), None) + return ( + guest_access + and guest_access.content + and "guest_access" in guest_access.content + and guest_access.content["guest_access"] == "can_join" + ) + + def _should_do_dance(self, context, inviter, room_hosts=None): + # TODO: Shouldn't this be remote_room_host? + room_hosts = room_hosts or [] + + is_host_in_room = self.is_host_in_room(context.current_state) + if is_host_in_room: + return False, room_hosts + + if inviter and not self.hs.is_mine(inviter): + room_hosts.append(inviter.domain) + + return True, room_hosts + + @defer.inlineCallbacks + def lookup_room_alias(self, room_alias): + """ + Get the room ID associated with a room alias. + + Args: + room_alias (RoomAlias): The alias to look up. + Returns: + A tuple of: + The room ID as a RoomID object. + Hosts likely to be participating in the room ([str]). + Raises: + SynapseError if room alias could not be found. + """ + directory_handler = self.hs.get_handlers().directory_handler + mapping = yield directory_handler.get_association(room_alias) + + if not mapping: + raise SynapseError(404, "No such room alias") + + room_id = mapping["room_id"] + servers = mapping["servers"] + + defer.returnValue((RoomID.from_string(room_id), servers)) + + def get_inviter(self, user_id, current_state): + prev_state = current_state.get((EventTypes.Member, user_id)) + if prev_state and prev_state.membership == Membership.INVITE: + return UserID.from_string(prev_state.user_id) + return None + + @defer.inlineCallbacks + def get_joined_rooms_for_user(self, user): + """Returns a list of roomids that the user has any of the given + membership states in.""" + + rooms = yield self.store.get_rooms_for_user( + user.to_string(), + ) + + # For some reason the list of events contains duplicates + # TODO(paul): work out why because I really don't think it should + room_ids = set(r.room_id for r in rooms) + + defer.returnValue(room_ids) + + @defer.inlineCallbacks + def do_3pid_invite( + self, + room_id, + inviter, + medium, + address, + id_server, + requester, + txn_id + ): + invitee = yield self._lookup_3pid( + id_server, medium, address + ) + + if invitee: + handler = self.hs.get_handlers().room_member_handler + yield handler.update_membership( + requester, + UserID.from_string(invitee), + room_id, + "invite", + txn_id=txn_id, + ) + else: + yield self._make_and_store_3pid_invite( + requester, + id_server, + medium, + address, + room_id, + inviter, + txn_id=txn_id + ) + + @defer.inlineCallbacks + def _lookup_3pid(self, id_server, medium, address): + """Looks up a 3pid in the passed identity server. + + Args: + id_server (str): The server name (including port, if required) + of the identity server to use. + medium (str): The type of the third party identifier (e.g. "email"). + address (str): The third party identifier (e.g. "foo@example.com"). + + Returns: + str: the matrix ID of the 3pid, or None if it is not recognized. + """ + try: + data = yield self.hs.get_simple_http_client().get_json( + "%s%s/_matrix/identity/api/v1/lookup" % (id_server_scheme, id_server,), + { + "medium": medium, + "address": address, + } + ) + + if "mxid" in data: + if "signatures" not in data: + raise AuthError(401, "No signatures on 3pid binding") + self.verify_any_signature(data, id_server) + defer.returnValue(data["mxid"]) + + except IOError as e: + logger.warn("Error from identity server lookup: %s" % (e,)) + defer.returnValue(None) + + @defer.inlineCallbacks + def verify_any_signature(self, data, server_hostname): + if server_hostname not in data["signatures"]: + raise AuthError(401, "No signature from server %s" % (server_hostname,)) + for key_name, signature in data["signatures"][server_hostname].items(): + key_data = yield self.hs.get_simple_http_client().get_json( + "%s%s/_matrix/identity/api/v1/pubkey/%s" % + (id_server_scheme, server_hostname, key_name,), + ) + if "public_key" not in key_data: + raise AuthError(401, "No public key named %s from %s" % + (key_name, server_hostname,)) + verify_signed_json( + data, + server_hostname, + decode_verify_key_bytes(key_name, decode_base64(key_data["public_key"])) + ) + return + + @defer.inlineCallbacks + def _make_and_store_3pid_invite( + self, + requester, + id_server, + medium, + address, + room_id, + user, + txn_id + ): + room_state = yield self.hs.get_state_handler().get_current_state(room_id) + + inviter_display_name = "" + inviter_avatar_url = "" + member_event = room_state.get((EventTypes.Member, user.to_string())) + if member_event: + inviter_display_name = member_event.content.get("displayname", "") + inviter_avatar_url = member_event.content.get("avatar_url", "") + + canonical_room_alias = "" + canonical_alias_event = room_state.get((EventTypes.CanonicalAlias, "")) + if canonical_alias_event: + canonical_room_alias = canonical_alias_event.content.get("alias", "") + + room_name = "" + room_name_event = room_state.get((EventTypes.Name, "")) + if room_name_event: + room_name = room_name_event.content.get("name", "") + + room_join_rules = "" + join_rules_event = room_state.get((EventTypes.JoinRules, "")) + if join_rules_event: + room_join_rules = join_rules_event.content.get("join_rule", "") + + room_avatar_url = "" + room_avatar_event = room_state.get((EventTypes.RoomAvatar, "")) + if room_avatar_event: + room_avatar_url = room_avatar_event.content.get("url", "") + + token, public_keys, fallback_public_key, display_name = ( + yield self._ask_id_server_for_third_party_invite( + id_server=id_server, + medium=medium, + address=address, + room_id=room_id, + inviter_user_id=user.to_string(), + room_alias=canonical_room_alias, + room_avatar_url=room_avatar_url, + room_join_rules=room_join_rules, + room_name=room_name, + inviter_display_name=inviter_display_name, + inviter_avatar_url=inviter_avatar_url + ) + ) + + msg_handler = self.hs.get_handlers().message_handler + yield msg_handler.create_and_send_nonmember_event( + requester, + { + "type": EventTypes.ThirdPartyInvite, + "content": { + "display_name": display_name, + "public_keys": public_keys, + + # For backwards compatibility: + "key_validity_url": fallback_public_key["key_validity_url"], + "public_key": fallback_public_key["public_key"], + }, + "room_id": room_id, + "sender": user.to_string(), + "state_key": token, + }, + txn_id=txn_id, + ) + + @defer.inlineCallbacks + def _ask_id_server_for_third_party_invite( + self, + id_server, + medium, + address, + room_id, + inviter_user_id, + room_alias, + room_avatar_url, + room_join_rules, + room_name, + inviter_display_name, + inviter_avatar_url + ): + """ + Asks an identity server for a third party invite. + + Args: + id_server (str): hostname + optional port for the identity server. + medium (str): The literal string "email". + address (str): The third party address being invited. + room_id (str): The ID of the room to which the user is invited. + inviter_user_id (str): The user ID of the inviter. + room_alias (str): An alias for the room, for cosmetic notifications. + room_avatar_url (str): The URL of the room's avatar, for cosmetic + notifications. + room_join_rules (str): The join rules of the email (e.g. "public"). + room_name (str): The m.room.name of the room. + inviter_display_name (str): The current display name of the + inviter. + inviter_avatar_url (str): The URL of the inviter's avatar. + + Returns: + A deferred tuple containing: + token (str): The token which must be signed to prove authenticity. + public_keys ([{"public_key": str, "key_validity_url": str}]): + public_key is a base64-encoded ed25519 public key. + fallback_public_key: One element from public_keys. + display_name (str): A user-friendly name to represent the invited + user. + """ + + is_url = "%s%s/_matrix/identity/api/v1/store-invite" % ( + id_server_scheme, id_server, + ) + + invite_config = { + "medium": medium, + "address": address, + "room_id": room_id, + "room_alias": room_alias, + "room_avatar_url": room_avatar_url, + "room_join_rules": room_join_rules, + "room_name": room_name, + "sender": inviter_user_id, + "sender_display_name": inviter_display_name, + "sender_avatar_url": inviter_avatar_url, + } + + if self.hs.config.invite_3pid_guest: + registration_handler = self.hs.get_handlers().registration_handler + guest_access_token = yield registration_handler.guest_access_token_for( + medium=medium, + address=address, + inviter_user_id=inviter_user_id, + ) + + guest_user_info = yield self.hs.get_auth().get_user_by_access_token( + guest_access_token + ) + + invite_config.update({ + "guest_access_token": guest_access_token, + "guest_user_id": guest_user_info["user"].to_string(), + }) + + data = yield self.hs.get_simple_http_client().post_urlencoded_get_json( + is_url, + invite_config + ) + # TODO: Check for success + token = data["token"] + public_keys = data.get("public_keys", []) + if "public_key" in data: + fallback_public_key = { + "public_key": data["public_key"], + "key_validity_url": "%s%s/_matrix/identity/api/v1/pubkey/isvalid" % ( + id_server_scheme, id_server, + ), + } + else: + fallback_public_key = public_keys[0] + + if not public_keys: + public_keys.append(fallback_public_key) + display_name = data["display_name"] + defer.returnValue((token, public_keys, fallback_public_key, display_name)) + + @defer.inlineCallbacks + def forget(self, user, room_id): + user_id = user.to_string() + + member = yield self.state_handler.get_current_state( + room_id=room_id, + event_type=EventTypes.Member, + state_key=user_id + ) + membership = member.membership if member else None + + if membership is not None and membership != Membership.LEAVE: + raise SynapseError(400, "User %s in room %s" % ( + user_id, room_id + )) + + if membership: + yield self.store.forget(user_id, room_id) |