MatrixSynapse/synapse/api/auth_blocking.py

127 lines
5.2 KiB
Python
Raw Normal View History

# -*- coding: utf-8 -*-
# Copyright 2020 The Matrix.org Foundation C.I.C.
#
# 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.
import logging
from typing import Optional
from synapse.api.constants import LimitBlockingTypes, UserTypes
from synapse.api.errors import Codes, ResourceLimitError
from synapse.config.server import is_threepid_reserved
from synapse.types import Requester
logger = logging.getLogger(__name__)
2020-09-04 12:54:56 +02:00
class AuthBlocking:
def __init__(self, hs):
self.store = hs.get_datastore()
self._server_notices_mxid = hs.config.server_notices_mxid
self._hs_disabled = hs.config.hs_disabled
self._hs_disabled_message = hs.config.hs_disabled_message
self._admin_contact = hs.config.admin_contact
self._max_mau_value = hs.config.max_mau_value
self._limit_usage_by_mau = hs.config.limit_usage_by_mau
self._mau_limits_reserved_threepids = hs.config.mau_limits_reserved_threepids
self._server_name = hs.hostname
async def check_auth_blocking(
self,
user_id: Optional[str] = None,
threepid: Optional[dict] = None,
user_type: Optional[str] = None,
requester: Optional[Requester] = 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: If present, checks for presence against existing
MAU cohort
threepid: 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.
user_type: If present, is used to decide whether to check against
certain blocking reasons like MAU.
requester: If present, and the authenticated entity is a user, checks for
presence against existing MAU cohort. Passing in both a `user_id` and
`requester` is an error.
"""
if requester and user_id:
raise Exception(
"Passed in both 'user_id' and 'requester' to 'check_auth_blocking'"
)
if requester:
if requester.authenticated_entity.startswith("@"):
user_id = requester.authenticated_entity
elif requester.authenticated_entity == self._server_name:
# We never block the server from doing actions on behalf of
# users.
return
# 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._server_notices_mxid:
return
if await self.store.is_support_user(user_id):
return
if self._hs_disabled:
raise ResourceLimitError(
403,
self._hs_disabled_message,
errcode=Codes.RESOURCE_LIMIT_EXCEEDED,
admin_contact=self._admin_contact,
limit_type=LimitBlockingTypes.HS_DISABLED,
)
if self._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 = await self.store.user_last_seen_monthly_active(user_id)
if timestamp:
return
is_trial = await 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._mau_limits_reserved_threepids, threepid):
return
elif user_type == UserTypes.SUPPORT:
# If the user does not exist yet and is of type "support",
# allow registration. Support users are excluded from MAU checks.
return
# Else if there is no room in the MAU bucket, bail
current_mau = await self.store.get_monthly_active_count()
if current_mau >= self._max_mau_value:
raise ResourceLimitError(
403,
"Monthly Active User Limit Exceeded",
admin_contact=self._admin_contact,
errcode=Codes.RESOURCE_LIMIT_EXCEEDED,
limit_type=LimitBlockingTypes.MONTHLY_ACTIVE_USER,
)