forked-synapse/synapse/rest/key/v2/local_key_resource.py
Patrick Cloke def480442d
Declare support for Matrix 1.6 (#15559)
Adds logging for key server requests which include a key ID.
This is technically in violation of the 1.6 spec, but is the only
way to remain backwards compatibly with earlier versions of
Synapse (and possibly other homeservers) which *did* include
the key ID.
2023-05-12 07:31:50 -04:00

119 lines
4.3 KiB
Python

# 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.
import logging
import re
from typing import TYPE_CHECKING, Optional, Tuple
from signedjson.sign import sign_json
from unpaddedbase64 import encode_base64
from twisted.web.server import Request
from synapse.http.servlet import RestServlet
from synapse.types import JsonDict
if TYPE_CHECKING:
from synapse.server import HomeServer
logger = logging.getLogger(__name__)
class LocalKey(RestServlet):
"""HTTP resource containing encoding the TLS X.509 certificate and NACL
signature verification keys for this server::
GET /_matrix/key/v2/server HTTP/1.1
GET /_matrix/key/v2/server/a.key.id HTTP/1.1
HTTP/1.1 200 OK
Content-Type: application/json
{
"valid_until_ts": # integer posix timestamp when this result expires.
"server_name": "this.server.example.com"
"verify_keys": {
"algorithm:version": {
"key": # base64 encoded NACL verification key.
}
},
"old_verify_keys": {
"algorithm:version": {
"expired_ts": # integer posix timestamp when the key expired.
"key": # base64 encoded NACL verification key.
}
},
"signatures": {
"this.server.example.com": {
"algorithm:version": # NACL signature for this server
}
}
}
"""
PATTERNS = (re.compile("^/_matrix/key/v2/server(/(?P<key_id>[^/]*))?$"),)
def __init__(self, hs: "HomeServer"):
self.config = hs.config
self.clock = hs.get_clock()
self.update_response_body(self.clock.time_msec())
def update_response_body(self, time_now_msec: int) -> None:
refresh_interval = self.config.key.key_refresh_interval
self.valid_until_ts = int(time_now_msec + refresh_interval)
self.response_body = self.response_json_object()
def response_json_object(self) -> JsonDict:
verify_keys = {}
for signing_key in self.config.key.signing_key:
verify_key_bytes = signing_key.verify_key.encode()
key_id = "%s:%s" % (signing_key.alg, signing_key.version)
verify_keys[key_id] = {"key": encode_base64(verify_key_bytes)}
old_verify_keys = {}
for key_id, old_signing_key in self.config.key.old_signing_keys.items():
verify_key_bytes = old_signing_key.encode()
old_verify_keys[key_id] = {
"key": encode_base64(verify_key_bytes),
"expired_ts": old_signing_key.expired,
}
json_object = {
"valid_until_ts": self.valid_until_ts,
"server_name": self.config.server.server_name,
"verify_keys": verify_keys,
"old_verify_keys": old_verify_keys,
}
for key in self.config.key.signing_key:
json_object = sign_json(json_object, self.config.server.server_name, key)
return json_object
def on_GET(
self, request: Request, key_id: Optional[str] = None
) -> Tuple[int, JsonDict]:
# Matrix 1.6 drops support for passing the key_id, this is incompatible
# with earlier versions and is allowed in order to support both.
# A warning is issued to help determine when it is safe to drop this.
if key_id:
logger.warning(
"Request for local server key with deprecated key ID (logging to determine usage level for future removal): %s",
key_id,
)
time_now = self.clock.time_msec()
# Update the expiry time if less than half the interval remains.
if time_now + self.config.key.key_refresh_interval / 2 > self.valid_until_ts:
self.update_response_body(time_now)
return 200, self.response_body