forked-synapse/synapse/visibility.py
David Baker e1f1784f99 Fix rejection of invites not reaching sync
Always allow the user to see their own leave events, otherwise
they won't see the event if they reject an invite for a room whose
history visibility is set such that they cannot see events before
joining.
2017-03-23 18:50:31 +00:00

237 lines
8.2 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2014 - 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 synapse.api.constants import Membership, EventTypes
from synapse.util.logcontext import preserve_fn, preserve_context_over_deferred
import logging
logger = logging.getLogger(__name__)
VISIBILITY_PRIORITY = (
"world_readable",
"shared",
"invited",
"joined",
)
MEMBERSHIP_PRIORITY = (
Membership.JOIN,
Membership.INVITE,
Membership.KNOCK,
Membership.LEAVE,
Membership.BAN,
)
@defer.inlineCallbacks
def filter_events_for_clients(store, user_tuples, events, event_id_to_state):
""" Returns dict of user_id -> list of events that user is allowed to
see.
Args:
user_tuples (str, bool): (user id, is_peeking) for each user to be
checked. is_peeking should be true if:
* the user is not currently a member of the room, and:
* the user has not been a member of the room since the
given events
events ([synapse.events.EventBase]): list of events to filter
"""
forgotten = yield preserve_context_over_deferred(defer.gatherResults([
preserve_fn(store.who_forgot_in_room)(
room_id,
)
for room_id in frozenset(e.room_id for e in events)
], consumeErrors=True))
# Set of membership event_ids that have been forgotten
event_id_forgotten = frozenset(
row["event_id"] for rows in forgotten for row in rows
)
ignore_dict_content = yield store.get_global_account_data_by_type_for_users(
"m.ignored_user_list", user_ids=[user_id for user_id, _ in user_tuples]
)
# FIXME: This will explode if people upload something incorrect.
ignore_dict = {
user_id: frozenset(
content.get("ignored_users", {}).keys() if content else []
)
for user_id, content in ignore_dict_content.items()
}
def allowed(event, user_id, is_peeking, ignore_list):
"""
Args:
event (synapse.events.EventBase): event to check
user_id (str)
is_peeking (bool)
ignore_list (list): list of users to ignore
"""
if not event.is_state() and event.sender in ignore_list:
return False
state = event_id_to_state[event.event_id]
# get the room_visibility at the time of the event.
visibility_event = state.get((EventTypes.RoomHistoryVisibility, ""), None)
if visibility_event:
visibility = visibility_event.content.get("history_visibility", "shared")
else:
visibility = "shared"
if visibility not in VISIBILITY_PRIORITY:
visibility = "shared"
# if it was world_readable, it's easy: everyone can read it
if visibility == "world_readable":
return True
# Always allow history visibility events on boundaries. This is done
# by setting the effective visibility to the least restrictive
# of the old vs new.
if event.type == EventTypes.RoomHistoryVisibility:
prev_content = event.unsigned.get("prev_content", {})
prev_visibility = prev_content.get("history_visibility", None)
if prev_visibility not in VISIBILITY_PRIORITY:
prev_visibility = "shared"
new_priority = VISIBILITY_PRIORITY.index(visibility)
old_priority = VISIBILITY_PRIORITY.index(prev_visibility)
if old_priority < new_priority:
visibility = prev_visibility
# likewise, if the event is the user's own membership event, use
# the 'most joined' membership
membership = None
if event.type == EventTypes.Member and event.state_key == user_id:
membership = event.content.get("membership", None)
if membership not in MEMBERSHIP_PRIORITY:
membership = "leave"
prev_content = event.unsigned.get("prev_content", {})
prev_membership = prev_content.get("membership", None)
if prev_membership not in MEMBERSHIP_PRIORITY:
prev_membership = "leave"
# Always allow the user to see their own leave events, otherwise
# they won't see the room disappear if they reject the invite
if membership == "leave" and (
prev_membership == "join" or prev_membership == "invite"
):
return True
new_priority = MEMBERSHIP_PRIORITY.index(membership)
old_priority = MEMBERSHIP_PRIORITY.index(prev_membership)
if old_priority < new_priority:
membership = prev_membership
# otherwise, get the user's membership at the time of the event.
if membership is None:
membership_event = state.get((EventTypes.Member, user_id), None)
if membership_event:
if membership_event.event_id not in event_id_forgotten:
membership = membership_event.membership
# if the user was a member of the room at the time of the event,
# they can see it.
if membership == Membership.JOIN:
return True
if visibility == "joined":
# we weren't a member at the time of the event, so we can't
# see this event.
return False
elif visibility == "invited":
# user can also see the event if they were *invited* at the time
# of the event.
return membership == Membership.INVITE
else:
# visibility is shared: user can also see the event if they have
# become a member since the event
#
# XXX: if the user has subsequently joined and then left again,
# ideally we would share history up to the point they left. But
# we don't know when they left.
return not is_peeking
defer.returnValue({
user_id: [
event
for event in events
if allowed(event, user_id, is_peeking, ignore_dict.get(user_id, []))
]
for user_id, is_peeking in user_tuples
})
@defer.inlineCallbacks
def filter_events_for_clients_context(store, user_tuples, events, event_id_to_context):
user_ids = set(u[0] for u in user_tuples)
event_id_to_state = {}
for event_id, context in event_id_to_context.items():
state = yield store.get_events([
e_id
for key, e_id in context.current_state_ids.iteritems()
if key == (EventTypes.RoomHistoryVisibility, "")
or (key[0] == EventTypes.Member and key[1] in user_ids)
])
event_id_to_state[event_id] = state
res = yield filter_events_for_clients(
store, user_tuples, events, event_id_to_state
)
defer.returnValue(res)
@defer.inlineCallbacks
def filter_events_for_client(store, user_id, events, is_peeking=False):
"""
Check which events a user is allowed to see
Args:
user_id(str): user id to be checked
events([synapse.events.EventBase]): list of events to be checked
is_peeking(bool): should be True if:
* the user is not currently a member of the room, and:
* the user has not been a member of the room since the given
events
Returns:
[synapse.events.EventBase]
"""
types = (
(EventTypes.RoomHistoryVisibility, ""),
(EventTypes.Member, user_id),
)
event_id_to_state = yield store.get_state_for_events(
frozenset(e.event_id for e in events),
types=types
)
res = yield filter_events_for_clients(
store, [(user_id, is_peeking)], events, event_id_to_state
)
defer.returnValue(res.get(user_id, []))