forked-synapse/synapse/storage/databases/main/keys.py
Patrick Cloke 5e024a0645
Modify StoreKeyFetcher to read from server_keys_json. (#15417)
Before this change:

* `PerspectivesKeyFetcher` and `ServerKeyFetcher` write to `server_keys_json`.
* `PerspectivesKeyFetcher` also writes to `server_signature_keys`.
* `StoreKeyFetcher` reads from `server_signature_keys`.

After this change:

* `PerspectivesKeyFetcher` and `ServerKeyFetcher` write to `server_keys_json`.
* `PerspectivesKeyFetcher` also writes to `server_signature_keys`.
* `StoreKeyFetcher` reads from `server_keys_json`.

This results in `StoreKeyFetcher` now using the results from `ServerKeyFetcher`
in addition to those from `PerspectivesKeyFetcher`, i.e. keys which are directly
fetched from a server will now be pulled from the database instead of refetched.

An additional minor change is included to avoid creating a `PerspectivesKeyFetcher`
(and checking it) if no `trusted_key_servers` are configured.

The overall impact of this should be better usage of cached results:

* If a server has no trusted key servers configured then it should reduce how often keys
  are fetched.
* if a server's trusted key server does not have a requested server's keys cached then it
  should reduce how often keys are directly fetched.
2023-04-20 12:30:32 -04:00

300 lines
11 KiB
Python

# 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 json
import logging
from typing import Any, Dict, Iterable, List, Mapping, Optional, Tuple
from signedjson.key import decode_verify_key_bytes
from unpaddedbase64 import decode_base64
from synapse.storage._base import SQLBaseStore
from synapse.storage.database import LoggingTransaction
from synapse.storage.keys import FetchKeyResult
from synapse.storage.types import Cursor
from synapse.util.caches.descriptors import cached, cachedList
from synapse.util.iterutils import batch_iter
logger = logging.getLogger(__name__)
db_binary_type = memoryview
class KeyStore(SQLBaseStore):
"""Persistence for signature verification keys"""
@cached()
def _get_server_signature_key(
self, server_name_and_key_id: Tuple[str, str]
) -> FetchKeyResult:
raise NotImplementedError()
@cachedList(
cached_method_name="_get_server_signature_key",
list_name="server_name_and_key_ids",
)
async def get_server_signature_keys(
self, server_name_and_key_ids: Iterable[Tuple[str, str]]
) -> Dict[Tuple[str, str], FetchKeyResult]:
"""
Args:
server_name_and_key_ids:
iterable of (server_name, key-id) tuples to fetch keys for
Returns:
A map from (server_name, key_id) -> FetchKeyResult, or None if the
key is unknown
"""
keys = {}
def _get_keys(txn: Cursor, batch: Tuple[Tuple[str, str], ...]) -> None:
"""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
keys[(server_name, key_id)] = FetchKeyResult(
verify_key=decode_verify_key_bytes(key_id, bytes(key_bytes)),
valid_until_ts=ts_valid_until_ms,
)
def _txn(txn: Cursor) -> Dict[Tuple[str, str], FetchKeyResult]:
for batch in batch_iter(server_name_and_key_ids, 50):
_get_keys(txn, batch)
return keys
return await self.db_pool.runInteraction("get_server_signature_keys", _txn)
async def store_server_signature_keys(
self,
from_server: str,
ts_added_ms: int,
verify_keys: Mapping[Tuple[str, str], FetchKeyResult],
) -> None:
"""Stores NACL verification keys for remote servers.
Args:
from_server: Where the verification keys were looked up
ts_added_ms: The time to record that the key was added
verify_keys:
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.items():
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_signature_key. _get_server_signature_key only takes one
# param, which is itself the 2-tuple (server_name, key_id).
invalidations.append((server_name, key_id))
await self.db_pool.simple_upsert_many(
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,
desc="store_server_signature_keys",
)
invalidate = self._get_server_signature_key.invalidate
for i in invalidations:
invalidate((i,))
async def store_server_keys_json(
self,
server_name: str,
key_id: str,
from_server: str,
ts_now_ms: int,
ts_expires_ms: int,
key_json_bytes: bytes,
) -> None:
"""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: The name of the server.
key_id: The identifier of the key this JSON is for.
from_server: The server this JSON was fetched from.
ts_now_ms: The time now in milliseconds.
ts_valid_until_ms: The time when this json stops being valid.
key_json_bytes: The encoded JSON.
"""
await self.db_pool.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",
)
# invalidate takes a tuple corresponding to the params of
# _get_server_keys_json. _get_server_keys_json only takes one
# param, which is itself the 2-tuple (server_name, key_id).
self._get_server_keys_json.invalidate((((server_name, key_id),)))
@cached()
def _get_server_keys_json(
self, server_name_and_key_id: Tuple[str, str]
) -> FetchKeyResult:
raise NotImplementedError()
@cachedList(
cached_method_name="_get_server_keys_json", list_name="server_name_and_key_ids"
)
async def get_server_keys_json(
self, server_name_and_key_ids: Iterable[Tuple[str, str]]
) -> Dict[Tuple[str, str], FetchKeyResult]:
"""
Args:
server_name_and_key_ids:
iterable of (server_name, key-id) tuples to fetch keys for
Returns:
A map from (server_name, key_id) -> FetchKeyResult, or None if the
key is unknown
"""
keys = {}
def _get_keys(txn: Cursor, batch: Tuple[Tuple[str, str], ...]) -> None:
"""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, key_json, ts_valid_until_ms
FROM server_keys_json WHERE 1=0
""" + " OR (server_name=? AND key_id=?)" * len(
batch
)
txn.execute(sql, tuple(itertools.chain.from_iterable(batch)))
for server_name, key_id, key_json_bytes, ts_valid_until_ms in txn:
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
# The entire signed JSON response is stored in server_keys_json,
# fetch out the bits needed.
key_json = json.loads(bytes(key_json_bytes))
key_base64 = key_json["verify_keys"][key_id]["key"]
keys[(server_name, key_id)] = FetchKeyResult(
verify_key=decode_verify_key_bytes(
key_id, decode_base64(key_base64)
),
valid_until_ts=ts_valid_until_ms,
)
def _txn(txn: Cursor) -> Dict[Tuple[str, str], FetchKeyResult]:
for batch in batch_iter(server_name_and_key_ids, 50):
_get_keys(txn, batch)
return keys
return await self.db_pool.runInteraction("get_server_keys_json", _txn)
async def get_server_keys_json_for_remote(
self, server_keys: Iterable[Tuple[str, Optional[str], Optional[str]]]
) -> Dict[Tuple[str, Optional[str], Optional[str]], List[Dict[str, Any]]]:
"""Retrieve 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 of (server_name, key_id, source) triplets.
Returns:
A mapping from (server_name, key_id, source) triplets to a list of dicts
"""
def _get_server_keys_json_txn(
txn: LoggingTransaction,
) -> Dict[Tuple[str, Optional[str], Optional[str]], List[Dict[str, Any]]]:
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.db_pool.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 await self.db_pool.runInteraction(
"get_server_keys_json", _get_server_keys_json_txn
)