From 43badd2cd4315c3f3ed45b0092c4479a43a3eb52 Mon Sep 17 00:00:00 2001
From: Erik Johnston <erik@matrix.org>
Date: Mon, 10 Jun 2019 14:31:05 +0100
Subject: [PATCH] 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.
---
synapse/storage/keys.py | 8 ++++++
tests/crypto/test_keyring.py | 50 +++++++++++++++++++++++++++++++++++-
2 files changed, 57 insertions(+), 1 deletion(-)
diff --git a/synapse/storage/keys.py b/synapse/storage/keys.py
index 5300720dbb..e3655ad8d7 100644
--- a/synapse/storage/keys.py
+++ b/synapse/storage/keys.py
@@ -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,
diff --git a/tests/crypto/test_keyring.py b/tests/crypto/test_keyring.py
index 4b1901ce31..5a355f00cc 100644
--- a/tests/crypto/test_keyring.py
+++ b/tests/crypto/test_keyring.py
@@ -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)
--
GitLab