# -*- coding: utf-8 -*-
# Copyright 2014-2016 OpenMarket Ltd
# Copyright 2019 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 itertools
import logging
import six
import attr
from signedjson.key import decode_verify_key_bytes
from synapse.util import batch_iter
from synapse.util.caches.descriptors import cached, cachedList
from ._base import SQLBaseStore
logger = logging.getLogger(__name__)
# py2 sqlite has buffer hardcoded as only binary type, so we must use it,
# despite being deprecated and removed in favor of memoryview
if six.PY2:
db_binary_type = six.moves.builtins.buffer
else:
db_binary_type = memoryview
@attr.s(slots=True, frozen=True)
class FetchKeyResult(object):
verify_key = attr.ib() # VerifyKey: the key itself
valid_until_ts = attr.ib() # int: how long we can use this key for
class KeyStore(SQLBaseStore):
"""Persistence for signature verification keys
"""
@cached()
def _get_server_verify_key(self, server_name_and_key_id):
raise NotImplementedError()
@cachedList(
cached_method_name="_get_server_verify_key", list_name="server_name_and_key_ids"
)
def get_server_verify_keys(self, server_name_and_key_ids):
"""
Args:
server_name_and_key_ids (iterable[Tuple[str, str]]):
iterable of (server_name, key-id) tuples to fetch keys for
Returns:
Deferred: resolves to dict[Tuple[str, str], FetchKeyResult|None]:
map from (server_name, key_id) -> FetchKeyResult, or None if the key is
unknown
"""
keys = {}
def _get_keys(txn, batch):
"""Processes a batch of keys to fetch, and adds the result to `keys`."""
# batch_iter always returns tuples so it's safe to do len(batch)
sql = (
"SELECT server_name, key_id, verify_key, ts_valid_until_ms "
"FROM server_signature_keys WHERE 1=0"
) + " OR (server_name=? AND key_id=?)" * len(batch)
txn.execute(sql, tuple(itertools.chain.from_iterable(batch)))
for row in txn:
server_name, key_id, key_bytes, ts_valid_until_ms = row
if ts_valid_until_ms is None:
# Old keys may be stored with a ts_valid_until_ms of null,
# in which case we treat this as if it was set to `0`, i.e.
# it won't match key requests that define a minimum
# `ts_valid_until_ms`.
ts_valid_until_ms = 0
res = FetchKeyResult(
verify_key=decode_verify_key_bytes(key_id, bytes(key_bytes)),
valid_until_ts=ts_valid_until_ms,
)
keys[(server_name, key_id)] = res
def _txn(txn):
for batch in batch_iter(server_name_and_key_ids, 50):
_get_keys(txn, batch)
return keys
return self.runInteraction("get_server_verify_keys", _txn)
def store_server_verify_keys(self, from_server, ts_added_ms, verify_keys):
"""Stores NACL verification keys for remote servers.
Args:
from_server (str): Where the verification keys were looked up
ts_added_ms (int): The time to record that the key was added
verify_keys (iterable[tuple[str, str, FetchKeyResult]]):
keys to be stored. Each entry is a triplet of
(server_name, key_id, key).
"""
key_values = []
value_values = []
invalidations = []
for server_name, key_id, fetch_result in verify_keys:
key_values.append((server_name, key_id))
value_values.append(
(
from_server,
ts_added_ms,
fetch_result.valid_until_ts,
db_binary_type(fetch_result.verify_key.encode()),
)
)
# invalidate takes a tuple corresponding to the params of
# _get_server_verify_key. _get_server_verify_key only takes one
# param, which is itself the 2-tuple (server_name, key_id).
invalidations.append((server_name, key_id))
def _invalidate(res):
f = self._get_server_verify_key.invalidate
for i in invalidations:
f((i,))
return res
return self.runInteraction(
"store_server_verify_keys",
self._simple_upsert_many_txn,
table="server_signature_keys",
key_names=("server_name", "key_id"),
key_values=key_values,
value_names=(
"from_server",
"ts_added_ms",
"ts_valid_until_ms",
"verify_key",
),
value_values=value_values,
).addCallback(_invalidate)
def store_server_keys_json(
self, server_name, key_id, from_server, ts_now_ms, ts_expires_ms, key_json_bytes
):
"""Stores the JSON bytes for a set of keys from a server
The JSON should be signed by the originating server, the intermediate
server, and by this server. Updates the value for the
(server_name, key_id, from_server) triplet if one already existed.
Args:
server_name (str): The name of the server.
key_id (str): The identifer of the key this JSON is for.
from_server (str): The server this JSON was fetched from.
ts_now_ms (int): The time now in milliseconds.
ts_valid_until_ms (int): The time when this json stops being valid.
key_json (bytes): The encoded JSON.
"""
return self._simple_upsert(
table="server_keys_json",
keyvalues={
"server_name": server_name,
"key_id": key_id,
"from_server": from_server,
},
values={
"server_name": server_name,
"key_id": key_id,
"from_server": from_server,
"ts_added_ms": ts_now_ms,
"ts_valid_until_ms": ts_expires_ms,
"key_json": db_binary_type(key_json_bytes),
},
desc="store_server_keys_json",
)
def get_server_keys_json(self, server_keys):
"""Retrive the key json for a list of server_keys and key ids.
If no keys are found for a given server, key_id and source then
that server, key_id, and source triplet entry will be an empty list.
The JSON is returned as a byte array so that it can be efficiently
used in an HTTP response.
Args:
server_keys (list): List of (server_name, key_id, source) triplets.
Returns:
Deferred[dict[Tuple[str, str, str|None], list[dict]]]:
Dict mapping (server_name, key_id, source) triplets to lists of dicts
"""
def _get_server_keys_json_txn(txn):
results = {}
for server_name, key_id, from_server in server_keys:
keyvalues = {"server_name": server_name}
if key_id is not None:
keyvalues["key_id"] = key_id
if from_server is not None:
keyvalues["from_server"] = from_server
rows = self._simple_select_list_txn(
txn,
"server_keys_json",
keyvalues=keyvalues,
retcols=(
"key_id",
"from_server",
"ts_added_ms",
"ts_valid_until_ms",
"key_json",
),
)
results[(server_name, key_id, from_server)] = rows
return results
return self.runInteraction("get_server_keys_json", _get_server_keys_json_txn)