Fix `destination_is` errors seen in sentry. (#13041)

* Rename test_fedclient to match its source file
* Require at least one destination to be truthy
* Explicitly validate user ID in profile endpoint GETs
Co-authored-by: Patrick Cloke <clokep@users.noreply.github.com>

1 files changed, 633 insertions, 0 deletions

diff --git a/tests/http/test_matrixfederationclient.py b/tests/http/test_matrixfederationclient.py
new file mode 100644
index 0000000000..be9eaf34e8
--- /dev/null
+++ b/tests/http/test_matrixfederationclient.py
@@ -0,0 +1,633 @@
+# Copyright 2018 New Vector 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.
+
+from unittest.mock import Mock
+
+from netaddr import IPSet
+from parameterized import parameterized
+
+from twisted.internet import defer
+from twisted.internet.defer import TimeoutError
+from twisted.internet.error import ConnectingCancelledError, DNSLookupError
+from twisted.test.proto_helpers import StringTransport
+from twisted.web.client import ResponseNeverReceived
+from twisted.web.http import HTTPChannel
+
+from synapse.api.errors import RequestSendFailed
+from synapse.http.matrixfederationclient import (
+    JsonParser,
+    MatrixFederationHttpClient,
+    MatrixFederationRequest,
+)
+from synapse.logging.context import SENTINEL_CONTEXT, LoggingContext, current_context
+
+from tests.server import FakeTransport
+from tests.unittest import HomeserverTestCase
+
+
+def check_logcontext(context):
+    current = current_context()
+    if current is not context:
+        raise AssertionError("Expected logcontext %s but was %s" % (context, current))
+
+
+class FederationClientTests(HomeserverTestCase):
+    def make_homeserver(self, reactor, clock):
+        hs = self.setup_test_homeserver(reactor=reactor, clock=clock)
+        return hs
+
+    def prepare(self, reactor, clock, homeserver):
+        self.cl = MatrixFederationHttpClient(self.hs, None)
+        self.reactor.lookups["testserv"] = "1.2.3.4"
+
+    def test_client_get(self):
+        """
+        happy-path test of a GET request
+        """
+
+        @defer.inlineCallbacks
+        def do_request():
+            with LoggingContext("one") as context:
+                fetch_d = defer.ensureDeferred(
+                    self.cl.get_json("testserv:8008", "foo/bar")
+                )
+
+                # Nothing happened yet
+                self.assertNoResult(fetch_d)
+
+                # should have reset logcontext to the sentinel
+                check_logcontext(SENTINEL_CONTEXT)
+
+                try:
+                    fetch_res = yield fetch_d
+                    return fetch_res
+                finally:
+                    check_logcontext(context)
+
+        test_d = do_request()
+
+        self.pump()
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        # Make sure treq is trying to connect
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, "1.2.3.4")
+        self.assertEqual(port, 8008)
+
+        # complete the connection and wire it up to a fake transport
+        protocol = factory.buildProtocol(None)
+        transport = StringTransport()
+        protocol.makeConnection(transport)
+
+        # that should have made it send the request to the transport
+        self.assertRegex(transport.value(), b"^GET /foo/bar")
+        self.assertRegex(transport.value(), b"Host: testserv:8008")
+
+        # Deferred is still without a result
+        self.assertNoResult(test_d)
+
+        # Send it the HTTP response
+        res_json = b'{ "a": 1 }'
+        protocol.dataReceived(
+            b"HTTP/1.1 200 OK\r\n"
+            b"Server: Fake\r\n"
+            b"Content-Type: application/json\r\n"
+            b"Content-Length: %i\r\n"
+            b"\r\n"
+            b"%s" % (len(res_json), res_json)
+        )
+
+        self.pump()
+
+        res = self.successResultOf(test_d)
+
+        # check the response is as expected
+        self.assertEqual(res, {"a": 1})
+
+    def test_dns_error(self):
+        """
+        If the DNS lookup returns an error, it will bubble up.
+        """
+        d = defer.ensureDeferred(
+            self.cl.get_json("testserv2:8008", "foo/bar", timeout=10000)
+        )
+        self.pump()
+
+        f = self.failureResultOf(d)
+        self.assertIsInstance(f.value, RequestSendFailed)
+        self.assertIsInstance(f.value.inner_exception, DNSLookupError)
+
+    def test_client_connection_refused(self):
+        d = defer.ensureDeferred(
+            self.cl.get_json("testserv:8008", "foo/bar", timeout=10000)
+        )
+
+        self.pump()
+
+        # Nothing happened yet
+        self.assertNoResult(d)
+
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, "1.2.3.4")
+        self.assertEqual(port, 8008)
+        e = Exception("go away")
+        factory.clientConnectionFailed(None, e)
+        self.pump(0.5)
+
+        f = self.failureResultOf(d)
+
+        self.assertIsInstance(f.value, RequestSendFailed)
+        self.assertIs(f.value.inner_exception, e)
+
+    def test_client_never_connect(self):
+        """
+        If the HTTP request is not connected and is timed out, it'll give a
+        ConnectingCancelledError or TimeoutError.
+        """
+        d = defer.ensureDeferred(
+            self.cl.get_json("testserv:8008", "foo/bar", timeout=10000)
+        )
+
+        self.pump()
+
+        # Nothing happened yet
+        self.assertNoResult(d)
+
+        # Make sure treq is trying to connect
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        self.assertEqual(clients[0][0], "1.2.3.4")
+        self.assertEqual(clients[0][1], 8008)
+
+        # Deferred is still without a result
+        self.assertNoResult(d)
+
+        # Push by enough to time it out
+        self.reactor.advance(10.5)
+        f = self.failureResultOf(d)
+
+        self.assertIsInstance(f.value, RequestSendFailed)
+        self.assertIsInstance(
+            f.value.inner_exception, (ConnectingCancelledError, TimeoutError)
+        )
+
+    def test_client_connect_no_response(self):
+        """
+        If the HTTP request is connected, but gets no response before being
+        timed out, it'll give a ResponseNeverReceived.
+        """
+        d = defer.ensureDeferred(
+            self.cl.get_json("testserv:8008", "foo/bar", timeout=10000)
+        )
+
+        self.pump()
+
+        # Nothing happened yet
+        self.assertNoResult(d)
+
+        # Make sure treq is trying to connect
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        self.assertEqual(clients[0][0], "1.2.3.4")
+        self.assertEqual(clients[0][1], 8008)
+
+        conn = Mock()
+        client = clients[0][2].buildProtocol(None)
+        client.makeConnection(conn)
+
+        # Deferred is still without a result
+        self.assertNoResult(d)
+
+        # Push by enough to time it out
+        self.reactor.advance(10.5)
+        f = self.failureResultOf(d)
+
+        self.assertIsInstance(f.value, RequestSendFailed)
+        self.assertIsInstance(f.value.inner_exception, ResponseNeverReceived)
+
+    def test_client_ip_range_blacklist(self):
+        """Ensure that Synapse does not try to connect to blacklisted IPs"""
+
+        # Set up the ip_range blacklist
+        self.hs.config.server.federation_ip_range_blacklist = IPSet(
+            ["127.0.0.0/8", "fe80::/64"]
+        )
+        self.reactor.lookups["internal"] = "127.0.0.1"
+        self.reactor.lookups["internalv6"] = "fe80:0:0:0:0:8a2e:370:7337"
+        self.reactor.lookups["fine"] = "10.20.30.40"
+        cl = MatrixFederationHttpClient(self.hs, None)
+
+        # Try making a GET request to a blacklisted IPv4 address
+        # ------------------------------------------------------
+        # Make the request
+        d = defer.ensureDeferred(cl.get_json("internal:8008", "foo/bar", timeout=10000))
+
+        # Nothing happened yet
+        self.assertNoResult(d)
+
+        self.pump(1)
+
+        # Check that it was unable to resolve the address
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 0)
+
+        f = self.failureResultOf(d)
+        self.assertIsInstance(f.value, RequestSendFailed)
+        self.assertIsInstance(f.value.inner_exception, DNSLookupError)
+
+        # Try making a POST request to a blacklisted IPv6 address
+        # -------------------------------------------------------
+        # Make the request
+        d = defer.ensureDeferred(
+            cl.post_json("internalv6:8008", "foo/bar", timeout=10000)
+        )
+
+        # Nothing has happened yet
+        self.assertNoResult(d)
+
+        # Move the reactor forwards
+        self.pump(1)
+
+        # Check that it was unable to resolve the address
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 0)
+
+        # Check that it was due to a blacklisted DNS lookup
+        f = self.failureResultOf(d, RequestSendFailed)
+        self.assertIsInstance(f.value.inner_exception, DNSLookupError)
+
+        # Try making a GET request to a non-blacklisted IPv4 address
+        # ----------------------------------------------------------
+        # Make the request
+        d = defer.ensureDeferred(cl.post_json("fine:8008", "foo/bar", timeout=10000))
+
+        # Nothing has happened yet
+        self.assertNoResult(d)
+
+        # Move the reactor forwards
+        self.pump(1)
+
+        # Check that it was able to resolve the address
+        clients = self.reactor.tcpClients
+        self.assertNotEqual(len(clients), 0)
+
+        # Connection will still fail as this IP address does not resolve to anything
+        f = self.failureResultOf(d, RequestSendFailed)
+        self.assertIsInstance(f.value.inner_exception, ConnectingCancelledError)
+
+    def test_client_gets_headers(self):
+        """
+        Once the client gets the headers, _request returns successfully.
+        """
+        request = MatrixFederationRequest(
+            method="GET", destination="testserv:8008", path="foo/bar"
+        )
+        d = defer.ensureDeferred(self.cl._send_request(request, timeout=10000))
+
+        self.pump()
+
+        conn = Mock()
+        clients = self.reactor.tcpClients
+        client = clients[0][2].buildProtocol(None)
+        client.makeConnection(conn)
+
+        # Deferred does not have a result
+        self.assertNoResult(d)
+
+        # Send it the HTTP response
+        client.dataReceived(b"HTTP/1.1 200 OK\r\nServer: Fake\r\n\r\n")
+
+        # We should get a successful response
+        r = self.successResultOf(d)
+        self.assertEqual(r.code, 200)
+
+    @parameterized.expand(["get_json", "post_json", "delete_json", "put_json"])
+    def test_timeout_reading_body(self, method_name: str):
+        """
+        If the HTTP request is connected, but gets no response before being
+        timed out, it'll give a RequestSendFailed with can_retry.
+        """
+        method = getattr(self.cl, method_name)
+        d = defer.ensureDeferred(method("testserv:8008", "foo/bar", timeout=10000))
+
+        self.pump()
+
+        conn = Mock()
+        clients = self.reactor.tcpClients
+        client = clients[0][2].buildProtocol(None)
+        client.makeConnection(conn)
+
+        # Deferred does not have a result
+        self.assertNoResult(d)
+
+        # Send it the HTTP response
+        client.dataReceived(
+            b"HTTP/1.1 200 OK\r\nContent-Type: application/json\r\n"
+            b"Server: Fake\r\n\r\n"
+        )
+
+        # Push by enough to time it out
+        self.reactor.advance(10.5)
+        f = self.failureResultOf(d)
+
+        self.assertIsInstance(f.value, RequestSendFailed)
+        self.assertTrue(f.value.can_retry)
+        self.assertIsInstance(f.value.inner_exception, defer.TimeoutError)
+
+    def test_client_requires_trailing_slashes(self):
+        """
+        If a connection is made to a client but the client rejects it due to
+        requiring a trailing slash. We need to retry the request with a
+        trailing slash. Workaround for Synapse <= v0.99.3, explained in #3622.
+        """
+        d = defer.ensureDeferred(
+            self.cl.get_json("testserv:8008", "foo/bar", try_trailing_slash_on_400=True)
+        )
+
+        # Send the request
+        self.pump()
+
+        # there should have been a call to connectTCP
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (_host, _port, factory, _timeout, _bindAddress) = clients[0]
+
+        # complete the connection and wire it up to a fake transport
+        client = factory.buildProtocol(None)
+        conn = StringTransport()
+        client.makeConnection(conn)
+
+        # that should have made it send the request to the connection
+        self.assertRegex(conn.value(), b"^GET /foo/bar")
+
+        # Clear the original request data before sending a response
+        conn.clear()
+
+        # Send the HTTP response
+        client.dataReceived(
+            b"HTTP/1.1 400 Bad Request\r\n"
+            b"Content-Type: application/json\r\n"
+            b"Content-Length: 59\r\n"
+            b"\r\n"
+            b'{"errcode":"M_UNRECOGNIZED","error":"Unrecognized request"}'
+        )
+
+        # We should get another request with a trailing slash
+        self.assertRegex(conn.value(), b"^GET /foo/bar/")
+
+        # Send a happy response this time
+        client.dataReceived(
+            b"HTTP/1.1 200 OK\r\n"
+            b"Content-Type: application/json\r\n"
+            b"Content-Length: 2\r\n"
+            b"\r\n"
+            b"{}"
+        )
+
+        # We should get a successful response
+        r = self.successResultOf(d)
+        self.assertEqual(r, {})
+
+    def test_client_does_not_retry_on_400_plus(self):
+        """
+        Another test for trailing slashes but now test that we don't retry on
+        trailing slashes on a non-400/M_UNRECOGNIZED response.
+
+        See test_client_requires_trailing_slashes() for context.
+        """
+        d = defer.ensureDeferred(
+            self.cl.get_json("testserv:8008", "foo/bar", try_trailing_slash_on_400=True)
+        )
+
+        # Send the request
+        self.pump()
+
+        # there should have been a call to connectTCP
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (_host, _port, factory, _timeout, _bindAddress) = clients[0]
+
+        # complete the connection and wire it up to a fake transport
+        client = factory.buildProtocol(None)
+        conn = StringTransport()
+        client.makeConnection(conn)
+
+        # that should have made it send the request to the connection
+        self.assertRegex(conn.value(), b"^GET /foo/bar")
+
+        # Clear the original request data before sending a response
+        conn.clear()
+
+        # Send the HTTP response
+        client.dataReceived(
+            b"HTTP/1.1 404 Not Found\r\n"
+            b"Content-Type: application/json\r\n"
+            b"Content-Length: 2\r\n"
+            b"\r\n"
+            b"{}"
+        )
+
+        # We should not get another request
+        self.assertEqual(conn.value(), b"")
+
+        # We should get a 404 failure response
+        self.failureResultOf(d)
+
+    def test_client_sends_body(self):
+        defer.ensureDeferred(
+            self.cl.post_json(
+                "testserv:8008", "foo/bar", timeout=10000, data={"a": "b"}
+            )
+        )
+
+        self.pump()
+
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        client = clients[0][2].buildProtocol(None)
+        server = HTTPChannel()
+
+        client.makeConnection(FakeTransport(server, self.reactor))
+        server.makeConnection(FakeTransport(client, self.reactor))
+
+        self.pump(0.1)
+
+        self.assertEqual(len(server.requests), 1)
+        request = server.requests[0]
+        content = request.content.read()
+        self.assertEqual(content, b'{"a":"b"}')
+
+    def test_closes_connection(self):
+        """Check that the client closes unused HTTP connections"""
+        d = defer.ensureDeferred(self.cl.get_json("testserv:8008", "foo/bar"))
+
+        self.pump()
+
+        # there should have been a call to connectTCP
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (_host, _port, factory, _timeout, _bindAddress) = clients[0]
+
+        # complete the connection and wire it up to a fake transport
+        client = factory.buildProtocol(None)
+        conn = StringTransport()
+        client.makeConnection(conn)
+
+        # that should have made it send the request to the connection
+        self.assertRegex(conn.value(), b"^GET /foo/bar")
+
+        # Send the HTTP response
+        client.dataReceived(
+            b"HTTP/1.1 200 OK\r\n"
+            b"Content-Type: application/json\r\n"
+            b"Content-Length: 2\r\n"
+            b"\r\n"
+            b"{}"
+        )
+
+        # We should get a successful response
+        r = self.successResultOf(d)
+        self.assertEqual(r, {})
+
+        self.assertFalse(conn.disconnecting)
+
+        # wait for a while
+        self.reactor.advance(120)
+
+        self.assertTrue(conn.disconnecting)
+
+    @parameterized.expand([(b"",), (b"foo",), (b'{"a": Infinity}',)])
+    def test_json_error(self, return_value):
+        """
+        Test what happens if invalid JSON is returned from the remote endpoint.
+        """
+
+        test_d = defer.ensureDeferred(self.cl.get_json("testserv:8008", "foo/bar"))
+
+        self.pump()
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        # Make sure treq is trying to connect
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, "1.2.3.4")
+        self.assertEqual(port, 8008)
+
+        # complete the connection and wire it up to a fake transport
+        protocol = factory.buildProtocol(None)
+        transport = StringTransport()
+        protocol.makeConnection(transport)
+
+        # that should have made it send the request to the transport
+        self.assertRegex(transport.value(), b"^GET /foo/bar")
+        self.assertRegex(transport.value(), b"Host: testserv:8008")
+
+        # Deferred is still without a result
+        self.assertNoResult(test_d)
+
+        # Send it the HTTP response
+        protocol.dataReceived(
+            b"HTTP/1.1 200 OK\r\n"
+            b"Server: Fake\r\n"
+            b"Content-Type: application/json\r\n"
+            b"Content-Length: %i\r\n"
+            b"\r\n"
+            b"%s" % (len(return_value), return_value)
+        )
+
+        self.pump()
+
+        f = self.failureResultOf(test_d)
+        self.assertIsInstance(f.value, RequestSendFailed)
+
+    def test_too_big(self):
+        """
+        Test what happens if a huge response is returned from the remote endpoint.
+        """
+
+        test_d = defer.ensureDeferred(self.cl.get_json("testserv:8008", "foo/bar"))
+
+        self.pump()
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        # Make sure treq is trying to connect
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, "1.2.3.4")
+        self.assertEqual(port, 8008)
+
+        # complete the connection and wire it up to a fake transport
+        protocol = factory.buildProtocol(None)
+        transport = StringTransport()
+        protocol.makeConnection(transport)
+
+        # that should have made it send the request to the transport
+        self.assertRegex(transport.value(), b"^GET /foo/bar")
+        self.assertRegex(transport.value(), b"Host: testserv:8008")
+
+        # Deferred is still without a result
+        self.assertNoResult(test_d)
+
+        # Send it a huge HTTP response
+        protocol.dataReceived(
+            b"HTTP/1.1 200 OK\r\n"
+            b"Server: Fake\r\n"
+            b"Content-Type: application/json\r\n"
+            b"\r\n"
+        )
+
+        self.pump()
+
+        # should still be waiting
+        self.assertNoResult(test_d)
+
+        sent = 0
+        chunk_size = 1024 * 512
+        while not test_d.called:
+            protocol.dataReceived(b"a" * chunk_size)
+            sent += chunk_size
+            self.assertLessEqual(sent, JsonParser.MAX_RESPONSE_SIZE)
+
+        self.assertEqual(sent, JsonParser.MAX_RESPONSE_SIZE)
+
+        f = self.failureResultOf(test_d)
+        self.assertIsInstance(f.value, RequestSendFailed)
+
+        self.assertTrue(transport.disconnecting)
+
+    def test_build_auth_headers_rejects_falsey_destinations(self) -> None:
+        with self.assertRaises(ValueError):
+            self.cl.build_auth_headers(None, b"GET", b"https://example.com")
+        with self.assertRaises(ValueError):
+            self.cl.build_auth_headers(b"", b"GET", b"https://example.com")
+        with self.assertRaises(ValueError):
+            self.cl.build_auth_headers(
+                None, b"GET", b"https://example.com", destination_is=b""
+            )
+        with self.assertRaises(ValueError):
+            self.cl.build_auth_headers(
+                b"", b"GET", b"https://example.com", destination_is=b""
+            )