Fix key verification when key stored with null valid_until_ms

Some keys are stored in the synapse database with a null valid_until_ms
which caused an exception to be thrown when using that key. We fix this
by treating nulls as zeroes, i.e. they keys will match verification
requests with a minimum_valid_until_ms of zero (i.e. don't validate ts)
but will not match requests with a non-zero minimum_valid_until_ms.

Fixes #5391.
This commit is contained in:
Erik Johnston 2019-06-10 14:31:05 +01:00
parent 7c455a86bc
commit 43badd2cd4
2 changed files with 57 additions and 1 deletions

View file

@ -80,6 +80,14 @@ class KeyStore(SQLBaseStore):
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,

View file

@ -25,7 +25,11 @@ from twisted.internet import defer
from synapse.api.errors import SynapseError
from synapse.crypto import keyring
from synapse.crypto.keyring import PerspectivesKeyFetcher, ServerKeyFetcher
from synapse.crypto.keyring import (
PerspectivesKeyFetcher,
ServerKeyFetcher,
StoreKeyFetcher,
)
from synapse.storage.keys import FetchKeyResult
from synapse.util import logcontext
from synapse.util.logcontext import LoggingContext
@ -219,6 +223,50 @@ class KeyringTestCase(unittest.HomeserverTestCase):
# self.assertFalse(d.called)
self.get_success(d)
def test_verify_json_for_server_with_null_valid_until_ms(self):
"""Tests that we correctly handle key requests for keys we've stored
with a null `ts_valid_until_ms`
"""
mock_fetcher = keyring.KeyFetcher()
mock_fetcher.get_keys = Mock(return_value=defer.succeed({}))
kr = keyring.Keyring(
self.hs, key_fetchers=(StoreKeyFetcher(self.hs), mock_fetcher)
)
key1 = signedjson.key.generate_signing_key(1)
r = self.hs.datastore.store_server_verify_keys(
"server9",
time.time() * 1000,
[("server9", get_key_id(key1), FetchKeyResult(get_verify_key(key1), None))],
)
self.get_success(r)
json1 = {}
signedjson.sign.sign_json(json1, "server9", key1)
# should fail immediately on an unsigned object
d = _verify_json_for_server(kr, "server9", {}, 0, "test unsigned")
self.failureResultOf(d, SynapseError)
# should fail on a signed object with a non-zero minimum_valid_until_ms,
# as it tries to refetch the keys and fails.
d = _verify_json_for_server(
kr, "server9", json1, 500, "test signed non-zero min"
)
self.get_failure(d, SynapseError)
# We expect the keyring tried to refetch the key once.
mock_fetcher.get_keys.assert_called_once_with(
{"server9": {get_key_id(key1): 500}}
)
# should succeed on a signed object with a 0 minimum_valid_until_ms
d = _verify_json_for_server(
kr, "server9", json1, 0, "test signed with zero min"
)
self.get_success(d)
def test_verify_json_dedupes_key_requests(self):
"""Two requests for the same key should be deduped."""
key1 = signedjson.key.generate_signing_key(1)