synapse-product/synapse/config/key.py
Richard van der Hoff fd463b4f5d
Comment out most options in the generated config. (#4863)
Make it so that most options in the config are optional, and commented out in
the generated config.

The reasons this is a good thing are as follows:

* If we decide that we should change the default for an option, we can do so,
  and only those admins that have deliberately chosen to override that option
  will be stuck on the old setting.

* It moves us towards a point where we can get rid of the super-surprising
  feature of synapse where the default settings for the config come from the
  generated yaml.

* It makes setting up a test config for unit testing an order of magnitude
  easier (see forthcoming PR).

* It makes the generated config more consistent, and hopefully easier for users
  to understand.
2019-03-19 10:06:40 +00:00

194 lines
7.1 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2015, 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 hashlib
import logging
import os
from signedjson.key import (
NACL_ED25519,
decode_signing_key_base64,
decode_verify_key_bytes,
generate_signing_key,
is_signing_algorithm_supported,
read_signing_keys,
write_signing_keys,
)
from unpaddedbase64 import decode_base64
from synapse.util.stringutils import random_string, random_string_with_symbols
from ._base import Config, ConfigError
logger = logging.getLogger(__name__)
class KeyConfig(Config):
def read_config(self, config):
self.signing_key = self.read_signing_key(config["signing_key_path"])
self.old_signing_keys = self.read_old_signing_keys(
config.get("old_signing_keys", {})
)
self.key_refresh_interval = self.parse_duration(
config.get("key_refresh_interval", "1d"),
)
self.perspectives = self.read_perspectives(
config.get("perspectives", {}).get("servers", {
"matrix.org": {"verify_keys": {
"ed25519:auto": {
"key": "Noi6WqcDj0QmPxCNQqgezwTlBKrfqehY1u2FyWP9uYw",
}
}}
})
)
self.macaroon_secret_key = config.get(
"macaroon_secret_key", self.registration_shared_secret
)
if not self.macaroon_secret_key:
# Unfortunately, there are people out there that don't have this
# set. Lets just be "nice" and derive one from their secret key.
logger.warn("Config is missing macaroon_secret_key")
seed = bytes(self.signing_key[0])
self.macaroon_secret_key = hashlib.sha256(seed).digest()
self.expire_access_token = config.get("expire_access_token", False)
# a secret which is used to calculate HMACs for form values, to stop
# falsification of values
self.form_secret = config.get("form_secret", None)
def default_config(self, config_dir_path, server_name, generate_secrets=False,
**kwargs):
base_key_name = os.path.join(config_dir_path, server_name)
if generate_secrets:
macaroon_secret_key = 'macaroon_secret_key: "%s"' % (
random_string_with_symbols(50),
)
form_secret = 'form_secret: "%s"' % random_string_with_symbols(50)
else:
macaroon_secret_key = "# macaroon_secret_key: <PRIVATE STRING>"
form_secret = "# form_secret: <PRIVATE STRING>"
return """\
# a secret which is used to sign access tokens. If none is specified,
# the registration_shared_secret is used, if one is given; otherwise,
# a secret key is derived from the signing key.
#
%(macaroon_secret_key)s
# Used to enable access token expiration.
#
#expire_access_token: False
# a secret which is used to calculate HMACs for form values, to stop
# falsification of values. Must be specified for the User Consent
# forms to work.
#
%(form_secret)s
## Signing Keys ##
# Path to the signing key to sign messages with
#
signing_key_path: "%(base_key_name)s.signing.key"
# The keys that the server used to sign messages with but won't use
# to sign new messages. E.g. it has lost its private key
#
#old_signing_keys:
# "ed25519:auto":
# # Base64 encoded public key
# key: "The public part of your old signing key."
# # Millisecond POSIX timestamp when the key expired.
# expired_ts: 123456789123
# How long key response published by this server is valid for.
# Used to set the valid_until_ts in /key/v2 APIs.
# Determines how quickly servers will query to check which keys
# are still valid.
#
#key_refresh_interval: 1d
# The trusted servers to download signing keys from.
#
#perspectives:
# servers:
# "matrix.org":
# verify_keys:
# "ed25519:auto":
# key: "Noi6WqcDj0QmPxCNQqgezwTlBKrfqehY1u2FyWP9uYw"
""" % locals()
def read_perspectives(self, perspectives_servers):
servers = {}
for server_name, server_config in perspectives_servers.items():
for key_id, key_data in server_config["verify_keys"].items():
if is_signing_algorithm_supported(key_id):
key_base64 = key_data["key"]
key_bytes = decode_base64(key_base64)
verify_key = decode_verify_key_bytes(key_id, key_bytes)
servers.setdefault(server_name, {})[key_id] = verify_key
return servers
def read_signing_key(self, signing_key_path):
signing_keys = self.read_file(signing_key_path, "signing_key")
try:
return read_signing_keys(signing_keys.splitlines(True))
except Exception as e:
raise ConfigError(
"Error reading signing_key: %s" % (str(e))
)
def read_old_signing_keys(self, old_signing_keys):
keys = {}
for key_id, key_data in old_signing_keys.items():
if is_signing_algorithm_supported(key_id):
key_base64 = key_data["key"]
key_bytes = decode_base64(key_base64)
verify_key = decode_verify_key_bytes(key_id, key_bytes)
verify_key.expired_ts = key_data["expired_ts"]
keys[key_id] = verify_key
else:
raise ConfigError(
"Unsupported signing algorithm for old key: %r" % (key_id,)
)
return keys
def generate_files(self, config):
signing_key_path = config["signing_key_path"]
if not self.path_exists(signing_key_path):
with open(signing_key_path, "w") as signing_key_file:
key_id = "a_" + random_string(4)
write_signing_keys(
signing_key_file, (generate_signing_key(key_id),),
)
else:
signing_keys = self.read_file(signing_key_path, "signing_key")
if len(signing_keys.split("\n")[0].split()) == 1:
# handle keys in the old format.
key_id = "a_" + random_string(4)
key = decode_signing_key_base64(
NACL_ED25519, key_id, signing_keys.split("\n")[0]
)
with open(signing_key_path, "w") as signing_key_file:
write_signing_keys(
signing_key_file, (key,),
)