From fec2dcb1a538ab8ab447f724af1a94d5b3517197 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> Date: Mon, 3 Jun 2019 22:59:51 +0100 Subject: Enforce validity period on server_keys for fed requests. (#5321) When handling incoming federation requests, make sure that we have an up-to-date copy of the signing key. We do not yet enforce the validity period for event signatures. --- tests/crypto/test_keyring.py | 135 ++++++++++++++++++++++++++++++++++--------- 1 file changed, 108 insertions(+), 27 deletions(-) (limited to 'tests/crypto/test_keyring.py') diff --git a/tests/crypto/test_keyring.py b/tests/crypto/test_keyring.py index 3933ad4347..096401938d 100644 --- a/tests/crypto/test_keyring.py +++ b/tests/crypto/test_keyring.py @@ -19,6 +19,7 @@ from mock import Mock import canonicaljson import signedjson.key import signedjson.sign +from signedjson.key import get_verify_key from twisted.internet import defer @@ -137,7 +138,7 @@ class KeyringTestCase(unittest.HomeserverTestCase): context_11.request = "11" res_deferreds = kr.verify_json_objects_for_server( - [("server10", json1), ("server11", {})] + [("server10", json1, 0), ("server11", {}, 0)] ) # the unsigned json should be rejected pretty quickly @@ -174,7 +175,7 @@ class KeyringTestCase(unittest.HomeserverTestCase): self.http_client.post_json.return_value = defer.Deferred() res_deferreds_2 = kr.verify_json_objects_for_server( - [("server10", json1)] + [("server10", json1, 0)] ) res_deferreds_2[0].addBoth(self.check_context, None) yield logcontext.make_deferred_yieldable(res_deferreds_2[0]) @@ -197,31 +198,108 @@ class KeyringTestCase(unittest.HomeserverTestCase): kr = keyring.Keyring(self.hs) key1 = signedjson.key.generate_signing_key(1) - key1_id = "%s:%s" % (key1.alg, key1.version) - r = self.hs.datastore.store_server_verify_keys( "server9", time.time() * 1000, - [ - ( - "server9", - key1_id, - FetchKeyResult(signedjson.key.get_verify_key(key1), 1000), - ), - ], + [("server9", get_key_id(key1), FetchKeyResult(get_verify_key(key1), 1000))], ) 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", {}) + d = _verify_json_for_server(kr, "server9", {}, 0) self.failureResultOf(d, SynapseError) - d = _verify_json_for_server(kr, "server9", json1) - self.assertFalse(d.called) + # should suceed on a signed object + d = _verify_json_for_server(kr, "server9", json1, 500) + # self.assertFalse(d.called) 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) + + def get_keys(keys_to_fetch): + # there should only be one request object (with the max validity) + self.assertEqual(keys_to_fetch, {"server1": {get_key_id(key1): 1500}}) + + return defer.succeed( + { + "server1": { + get_key_id(key1): FetchKeyResult(get_verify_key(key1), 1200) + } + } + ) + + mock_fetcher = keyring.KeyFetcher() + mock_fetcher.get_keys = Mock(side_effect=get_keys) + kr = keyring.Keyring(self.hs, key_fetchers=(mock_fetcher,)) + + json1 = {} + signedjson.sign.sign_json(json1, "server1", key1) + + # the first request should succeed; the second should fail because the key + # has expired + results = kr.verify_json_objects_for_server( + [("server1", json1, 500), ("server1", json1, 1500)] + ) + self.assertEqual(len(results), 2) + self.get_success(results[0]) + e = self.get_failure(results[1], SynapseError).value + self.assertEqual(e.errcode, "M_UNAUTHORIZED") + self.assertEqual(e.code, 401) + + # there should have been a single call to the fetcher + mock_fetcher.get_keys.assert_called_once() + + def test_verify_json_falls_back_to_other_fetchers(self): + """If the first fetcher cannot provide a recent enough key, we fall back""" + key1 = signedjson.key.generate_signing_key(1) + + def get_keys1(keys_to_fetch): + self.assertEqual(keys_to_fetch, {"server1": {get_key_id(key1): 1500}}) + return defer.succeed( + { + "server1": { + get_key_id(key1): FetchKeyResult(get_verify_key(key1), 800) + } + } + ) + + def get_keys2(keys_to_fetch): + self.assertEqual(keys_to_fetch, {"server1": {get_key_id(key1): 1500}}) + return defer.succeed( + { + "server1": { + get_key_id(key1): FetchKeyResult(get_verify_key(key1), 1200) + } + } + ) + + mock_fetcher1 = keyring.KeyFetcher() + mock_fetcher1.get_keys = Mock(side_effect=get_keys1) + mock_fetcher2 = keyring.KeyFetcher() + mock_fetcher2.get_keys = Mock(side_effect=get_keys2) + kr = keyring.Keyring(self.hs, key_fetchers=(mock_fetcher1, mock_fetcher2)) + + json1 = {} + signedjson.sign.sign_json(json1, "server1", key1) + + results = kr.verify_json_objects_for_server( + [("server1", json1, 1200), ("server1", json1, 1500)] + ) + self.assertEqual(len(results), 2) + self.get_success(results[0]) + e = self.get_failure(results[1], SynapseError).value + self.assertEqual(e.errcode, "M_UNAUTHORIZED") + self.assertEqual(e.code, 401) + + # there should have been a single call to each fetcher + mock_fetcher1.get_keys.assert_called_once() + mock_fetcher2.get_keys.assert_called_once() + class ServerKeyFetcherTestCase(unittest.HomeserverTestCase): def make_homeserver(self, reactor, clock): @@ -260,8 +338,8 @@ class ServerKeyFetcherTestCase(unittest.HomeserverTestCase): self.http_client.get_json.side_effect = get_json - server_name_and_key_ids = [(SERVER_NAME, ("key1",))] - keys = self.get_success(fetcher.get_keys(server_name_and_key_ids)) + keys_to_fetch = {SERVER_NAME: {"key1": 0}} + keys = self.get_success(fetcher.get_keys(keys_to_fetch)) k = keys[SERVER_NAME][testverifykey_id] self.assertEqual(k.valid_until_ts, VALID_UNTIL_TS) self.assertEqual(k.verify_key, testverifykey) @@ -288,9 +366,7 @@ class ServerKeyFetcherTestCase(unittest.HomeserverTestCase): # change the server name: it should cause a rejection response["server_name"] = "OTHER_SERVER" - self.get_failure( - fetcher.get_keys(server_name_and_key_ids), KeyLookupError - ) + self.get_failure(fetcher.get_keys(keys_to_fetch), KeyLookupError) class PerspectivesKeyFetcherTestCase(unittest.HomeserverTestCase): @@ -342,8 +418,8 @@ class PerspectivesKeyFetcherTestCase(unittest.HomeserverTestCase): self.http_client.post_json.side_effect = post_json - server_name_and_key_ids = [(SERVER_NAME, ("key1",))] - keys = self.get_success(fetcher.get_keys(server_name_and_key_ids)) + keys_to_fetch = {SERVER_NAME: {"key1": 0}} + keys = self.get_success(fetcher.get_keys(keys_to_fetch)) self.assertIn(SERVER_NAME, keys) k = keys[SERVER_NAME][testverifykey_id] self.assertEqual(k.valid_until_ts, VALID_UNTIL_TS) @@ -401,7 +477,7 @@ class PerspectivesKeyFetcherTestCase(unittest.HomeserverTestCase): def get_key_from_perspectives(response): fetcher = PerspectivesKeyFetcher(self.hs) - server_name_and_key_ids = [(SERVER_NAME, ("key1",))] + keys_to_fetch = {SERVER_NAME: {"key1": 0}} def post_json(destination, path, data, **kwargs): self.assertEqual(destination, self.mock_perspective_server.server_name) @@ -410,9 +486,7 @@ class PerspectivesKeyFetcherTestCase(unittest.HomeserverTestCase): self.http_client.post_json.side_effect = post_json - return self.get_success( - fetcher.get_keys(server_name_and_key_ids) - ) + return self.get_success(fetcher.get_keys(keys_to_fetch)) # start with a valid response so we can check we are testing the right thing response = build_response() @@ -435,6 +509,11 @@ class PerspectivesKeyFetcherTestCase(unittest.HomeserverTestCase): self.assertEqual(keys, {}, "Expected empty dict with missing origin server sig") +def get_key_id(key): + """Get the matrix ID tag for a given SigningKey or VerifyKey""" + return "%s:%s" % (key.alg, key.version) + + @defer.inlineCallbacks def run_in_context(f, *args, **kwargs): with LoggingContext("testctx") as ctx: @@ -445,14 +524,16 @@ def run_in_context(f, *args, **kwargs): defer.returnValue(rv) -def _verify_json_for_server(keyring, server_name, json_object): +def _verify_json_for_server(keyring, server_name, json_object, validity_time): """thin wrapper around verify_json_for_server which makes sure it is wrapped with the patched defer.inlineCallbacks. """ @defer.inlineCallbacks def v(): - rv1 = yield keyring.verify_json_for_server(server_name, json_object) + rv1 = yield keyring.verify_json_for_server( + server_name, json_object, validity_time + ) defer.returnValue(rv1) return run_in_context(v) -- cgit 1.5.1 From def5ea4062295759d7c28d9c2302187871a1bc72 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Mon, 3 Jun 2019 15:36:41 +0100 Subject: Don't bomb out on direct key fetches as soon as one fails --- synapse/crypto/keyring.py | 58 +++++++++++++++++++++++++++----------------- tests/crypto/test_keyring.py | 12 ++++----- 2 files changed, 41 insertions(+), 29 deletions(-) (limited to 'tests/crypto/test_keyring.py') diff --git a/synapse/crypto/keyring.py b/synapse/crypto/keyring.py index bef6498f4b..5660c96023 100644 --- a/synapse/crypto/keyring.py +++ b/synapse/crypto/keyring.py @@ -46,6 +46,7 @@ from synapse.api.errors import ( ) from synapse.storage.keys import FetchKeyResult from synapse.util import logcontext, unwrapFirstError +from synapse.util.async_helpers import yieldable_gather_results from synapse.util.logcontext import ( LoggingContext, PreserveLoggingContext, @@ -169,7 +170,12 @@ class Keyring(object): ) ) - logger.debug("Verifying for %s with key_ids %s", server_name, key_ids) + logger.debug( + "Verifying for %s with key_ids %s, min_validity %i", + server_name, + key_ids, + validity_time, + ) # add the key request to the queue, but don't start it off yet. verify_request = VerifyKeyRequest( @@ -744,34 +750,42 @@ class ServerKeyFetcher(BaseV2KeyFetcher): self.clock = hs.get_clock() self.client = hs.get_http_client() - @defer.inlineCallbacks def get_keys(self, keys_to_fetch): """see KeyFetcher.get_keys""" - # TODO make this more resilient - results = yield logcontext.make_deferred_yieldable( - defer.gatherResults( - [ - run_in_background( - self.get_server_verify_key_v2_direct, - server_name, - server_keys.keys(), - ) - for server_name, server_keys in keys_to_fetch.items() - ], - consumeErrors=True, - ).addErrback(unwrapFirstError) - ) - merged = {} - for result in results: - merged.update(result) + results = {} + + @defer.inlineCallbacks + def get_key(key_to_fetch_item): + server_name, key_ids = key_to_fetch_item + try: + keys = yield self.get_server_verify_key_v2_direct(server_name, key_ids) + results[server_name] = keys + except KeyLookupError as e: + logger.warning( + "Error looking up keys %s from %s: %s", key_ids, server_name, e + ) + except Exception: + logger.exception("Error getting keys %s from %s", key_ids, server_name) - defer.returnValue( - {server_name: keys for server_name, keys in merged.items() if keys} + return yieldable_gather_results(get_key, keys_to_fetch.items()).addCallback( + lambda _: results ) @defer.inlineCallbacks def get_server_verify_key_v2_direct(self, server_name, key_ids): + """ + + Args: + server_name (str): + key_ids (iterable[str]): + + Returns: + Deferred[dict[str, FetchKeyResult]]: map from key ID to lookup result + + Raises: + KeyLookupError if there was a problem making the lookup + """ keys = {} # type: dict[str, FetchKeyResult] for requested_key_id in key_ids: @@ -823,7 +837,7 @@ class ServerKeyFetcher(BaseV2KeyFetcher): ) keys.update(response_keys) - defer.returnValue({server_name: keys}) + defer.returnValue(keys) @defer.inlineCallbacks diff --git a/tests/crypto/test_keyring.py b/tests/crypto/test_keyring.py index 096401938d..4cff7e36c8 100644 --- a/tests/crypto/test_keyring.py +++ b/tests/crypto/test_keyring.py @@ -25,11 +25,7 @@ from twisted.internet import defer from synapse.api.errors import SynapseError from synapse.crypto import keyring -from synapse.crypto.keyring import ( - KeyLookupError, - PerspectivesKeyFetcher, - ServerKeyFetcher, -) +from synapse.crypto.keyring import PerspectivesKeyFetcher, ServerKeyFetcher from synapse.storage.keys import FetchKeyResult from synapse.util import logcontext from synapse.util.logcontext import LoggingContext @@ -364,9 +360,11 @@ class ServerKeyFetcherTestCase(unittest.HomeserverTestCase): bytes(res["key_json"]), canonicaljson.encode_canonical_json(response) ) - # change the server name: it should cause a rejection + # change the server name: the result should be ignored response["server_name"] = "OTHER_SERVER" - self.get_failure(fetcher.get_keys(keys_to_fetch), KeyLookupError) + + keys = self.get_success(fetcher.get_keys(keys_to_fetch)) + self.assertEqual(keys, {}) class PerspectivesKeyFetcherTestCase(unittest.HomeserverTestCase): -- cgit 1.5.1