forked-synapse/synapse/storage/e2e_room_keys.py
David Baker 497444f1fd Don't reuse backup versions
Since we don't actually delete the keys, just mark the versions
as deleted in the db rather than actually deleting them, then we
won't reuse versions.

Fixes https://github.com/vector-im/riot-web/issues/7448
2018-10-05 15:08:36 +01:00

321 lines
11 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2017 New Vector 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.
import simplejson as json
from twisted.internet import defer
from synapse.api.errors import StoreError
from ._base import SQLBaseStore
class EndToEndRoomKeyStore(SQLBaseStore):
@defer.inlineCallbacks
def get_e2e_room_key(self, user_id, version, room_id, session_id):
"""Get the encrypted E2E room key for a given session from a given
backup version of room_keys. We only store the 'best' room key for a given
session at a given time, as determined by the handler.
Args:
user_id(str): the user whose backup we're querying
version(str): the version ID of the backup for the set of keys we're querying
room_id(str): the ID of the room whose keys we're querying.
This is a bit redundant as it's implied by the session_id, but
we include for consistency with the rest of the API.
session_id(str): the session whose room_key we're querying.
Returns:
A deferred dict giving the session_data and message metadata for
this room key.
"""
row = yield self._simple_select_one(
table="e2e_room_keys",
keyvalues={
"user_id": user_id,
"version": version,
"room_id": room_id,
"session_id": session_id,
},
retcols=(
"first_message_index",
"forwarded_count",
"is_verified",
"session_data",
),
desc="get_e2e_room_key",
)
row["session_data"] = json.loads(row["session_data"])
defer.returnValue(row)
@defer.inlineCallbacks
def set_e2e_room_key(self, user_id, version, room_id, session_id, room_key):
"""Replaces or inserts the encrypted E2E room key for a given session in
a given backup
Args:
user_id(str): the user whose backup we're setting
version(str): the version ID of the backup we're updating
room_id(str): the ID of the room whose keys we're setting
session_id(str): the session whose room_key we're setting
room_key(dict): the room_key being set
Raises:
StoreError if stuff goes wrong, probably
"""
yield self._simple_upsert(
table="e2e_room_keys",
keyvalues={
"user_id": user_id,
"room_id": room_id,
"session_id": session_id,
},
values={
"version": version,
"first_message_index": room_key['first_message_index'],
"forwarded_count": room_key['forwarded_count'],
"is_verified": room_key['is_verified'],
"session_data": json.dumps(room_key['session_data']),
},
lock=False,
)
@defer.inlineCallbacks
def get_e2e_room_keys(
self, user_id, version, room_id=None, session_id=None
):
"""Bulk get the E2E room keys for a given backup, optionally filtered to a given
room, or a given session.
Args:
user_id(str): the user whose backup we're querying
version(str): the version ID of the backup for the set of keys we're querying
room_id(str): Optional. the ID of the room whose keys we're querying, if any.
If not specified, we return the keys for all the rooms in the backup.
session_id(str): Optional. the session whose room_key we're querying, if any.
If specified, we also require the room_id to be specified.
If not specified, we return all the keys in this version of
the backup (or for the specified room)
Returns:
A deferred list of dicts giving the session_data and message metadata for
these room keys.
"""
keyvalues = {
"user_id": user_id,
"version": version,
}
if room_id:
keyvalues['room_id'] = room_id
if session_id:
keyvalues['session_id'] = session_id
rows = yield self._simple_select_list(
table="e2e_room_keys",
keyvalues=keyvalues,
retcols=(
"user_id",
"room_id",
"session_id",
"first_message_index",
"forwarded_count",
"is_verified",
"session_data",
),
desc="get_e2e_room_keys",
)
sessions = {'rooms': {}}
for row in rows:
room_entry = sessions['rooms'].setdefault(row['room_id'], {"sessions": {}})
room_entry['sessions'][row['session_id']] = {
"first_message_index": row["first_message_index"],
"forwarded_count": row["forwarded_count"],
"is_verified": row["is_verified"],
"session_data": json.loads(row["session_data"]),
}
defer.returnValue(sessions)
@defer.inlineCallbacks
def delete_e2e_room_keys(
self, user_id, version, room_id=None, session_id=None
):
"""Bulk delete the E2E room keys for a given backup, optionally filtered to a given
room or a given session.
Args:
user_id(str): the user whose backup we're deleting from
version(str): the version ID of the backup for the set of keys we're deleting
room_id(str): Optional. the ID of the room whose keys we're deleting, if any.
If not specified, we delete the keys for all the rooms in the backup.
session_id(str): Optional. the session whose room_key we're querying, if any.
If specified, we also require the room_id to be specified.
If not specified, we delete all the keys in this version of
the backup (or for the specified room)
Returns:
A deferred of the deletion transaction
"""
keyvalues = {
"user_id": user_id,
"version": version,
}
if room_id:
keyvalues['room_id'] = room_id
if session_id:
keyvalues['session_id'] = session_id
yield self._simple_delete(
table="e2e_room_keys",
keyvalues=keyvalues,
desc="delete_e2e_room_keys",
)
@staticmethod
def _get_current_version(txn, user_id):
txn.execute(
"SELECT MAX(version) FROM e2e_room_keys_versions "
"WHERE user_id=? AND deleted=0",
(user_id,)
)
row = txn.fetchone()
if not row:
raise StoreError(404, 'No current backup version')
return row[0]
def get_e2e_room_keys_version_info(self, user_id, version=None):
"""Get info metadata about a version of our room_keys backup.
Args:
user_id(str): the user whose backup we're querying
version(str): Optional. the version ID of the backup we're querying about
If missing, we return the information about the current version.
Raises:
StoreError: with code 404 if there are no e2e_room_keys_versions present
Returns:
A deferred dict giving the info metadata for this backup version
"""
def _get_e2e_room_keys_version_info_txn(txn):
if version is None:
this_version = self._get_current_version(txn, user_id)
else:
this_version = version
result = self._simple_select_one_txn(
txn,
table="e2e_room_keys_versions",
keyvalues={
"user_id": user_id,
"version": this_version,
"deleted": 0,
},
retcols=(
"version",
"algorithm",
"auth_data",
),
)
result["auth_data"] = json.loads(result["auth_data"])
return result
return self.runInteraction(
"get_e2e_room_keys_version_info",
_get_e2e_room_keys_version_info_txn
)
def create_e2e_room_keys_version(self, user_id, info):
"""Atomically creates a new version of this user's e2e_room_keys store
with the given version info.
Args:
user_id(str): the user whose backup we're creating a version
info(dict): the info about the backup version to be created
Returns:
A deferred string for the newly created version ID
"""
def _create_e2e_room_keys_version_txn(txn):
txn.execute(
"SELECT MAX(version) FROM e2e_room_keys_versions WHERE user_id=?",
(user_id,)
)
current_version = txn.fetchone()[0]
if current_version is None:
current_version = '0'
new_version = str(int(current_version) + 1)
self._simple_insert_txn(
txn,
table="e2e_room_keys_versions",
values={
"user_id": user_id,
"version": new_version,
"algorithm": info["algorithm"],
"auth_data": json.dumps(info["auth_data"]),
},
)
return new_version
return self.runInteraction(
"create_e2e_room_keys_version_txn", _create_e2e_room_keys_version_txn
)
def delete_e2e_room_keys_version(self, user_id, version=None):
"""Delete a given backup version of the user's room keys.
Doesn't delete their actual key data.
Args:
user_id(str): the user whose backup version we're deleting
version(str): Optional. the version ID of the backup version we're deleting
If missing, we delete the current backup version info.
Raises:
StoreError: with code 404 if there are no e2e_room_keys_versions present,
or if the version requested doesn't exist.
"""
def _delete_e2e_room_keys_version_txn(txn):
if version is None:
this_version = self._get_current_version(txn, user_id)
else:
this_version = version
return self._simple_update_one_txn(
txn,
table="e2e_room_keys_versions",
keyvalues={
"user_id": user_id,
"version": this_version,
},
updatevalues={
"deleted": 1,
}
)
return self.runInteraction(
"delete_e2e_room_keys_version",
_delete_e2e_room_keys_version_txn
)