synapse/tests/http/test_proxyagent.py
Andrew Morgan 5b268997bd
Allow providing credentials to HTTPS_PROXY (#9657)
Addresses https://github.com/matrix-org/synapse-dinsic/issues/70

This PR causes `ProxyAgent` to attempt to extract credentials from an `HTTPS_PROXY` env var. If credentials are found, a `Proxy-Authorization` header ([details](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Proxy-Authorization)) is sent to the proxy server to authenticate against it. The headers are *not* passed to the remote server.

Also added some type hints.
2021-03-22 17:20:47 +00:00

533 lines
19 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2019 The Matrix.org Foundation C.I.C.
#
# 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 base64
import logging
import os
from typing import Optional
from unittest.mock import patch
import treq
from netaddr import IPSet
from twisted.internet import interfaces # noqa: F401
from twisted.internet.protocol import Factory
from twisted.protocols.tls import TLSMemoryBIOFactory
from twisted.web.http import HTTPChannel
from synapse.http.client import BlacklistingReactorWrapper
from synapse.http.proxyagent import ProxyAgent
from tests.http import TestServerTLSConnectionFactory, get_test_https_policy
from tests.server import FakeTransport, ThreadedMemoryReactorClock
from tests.unittest import TestCase
logger = logging.getLogger(__name__)
HTTPFactory = Factory.forProtocol(HTTPChannel)
class MatrixFederationAgentTests(TestCase):
def setUp(self):
self.reactor = ThreadedMemoryReactorClock()
def _make_connection(
self, client_factory, server_factory, ssl=False, expected_sni=None
):
"""Builds a test server, and completes the outgoing client connection
Args:
client_factory (interfaces.IProtocolFactory): the the factory that the
application is trying to use to make the outbound connection. We will
invoke it to build the client Protocol
server_factory (interfaces.IProtocolFactory): a factory to build the
server-side protocol
ssl (bool): If true, we will expect an ssl connection and wrap
server_factory with a TLSMemoryBIOFactory
expected_sni (bytes|None): the expected SNI value
Returns:
IProtocol: the server Protocol returned by server_factory
"""
if ssl:
server_factory = _wrap_server_factory_for_tls(server_factory)
server_protocol = server_factory.buildProtocol(None)
# now, tell the client protocol factory to build the client protocol,
# and wire the output of said protocol up to the server via
# a FakeTransport.
#
# Normally this would be done by the TCP socket code in Twisted, but we are
# stubbing that out here.
client_protocol = client_factory.buildProtocol(None)
client_protocol.makeConnection(
FakeTransport(server_protocol, self.reactor, client_protocol)
)
# tell the server protocol to send its stuff back to the client, too
server_protocol.makeConnection(
FakeTransport(client_protocol, self.reactor, server_protocol)
)
if ssl:
http_protocol = server_protocol.wrappedProtocol
tls_connection = server_protocol._tlsConnection
else:
http_protocol = server_protocol
tls_connection = None
# give the reactor a pump to get the TLS juices flowing (if needed)
self.reactor.advance(0)
if expected_sni is not None:
server_name = tls_connection.get_servername()
self.assertEqual(
server_name,
expected_sni,
"Expected SNI %s but got %s" % (expected_sni, server_name),
)
return http_protocol
def _test_request_direct_connection(self, agent, scheme, hostname, path):
"""Runs a test case for a direct connection not going through a proxy.
Args:
agent (ProxyAgent): the proxy agent being tested
scheme (bytes): expected to be either "http" or "https"
hostname (bytes): the hostname to connect to in the test
path (bytes): the path to connect to in the test
"""
is_https = scheme == b"https"
self.reactor.lookups[hostname.decode()] = "1.2.3.4"
d = agent.request(b"GET", scheme + b"://" + hostname + b"/" + path)
# there should be a pending TCP connection
clients = self.reactor.tcpClients
self.assertEqual(len(clients), 1)
(host, port, client_factory, _timeout, _bindAddress) = clients[0]
self.assertEqual(host, "1.2.3.4")
self.assertEqual(port, 443 if is_https else 80)
# make a test server, and wire up the client
http_server = self._make_connection(
client_factory,
_get_test_protocol_factory(),
ssl=is_https,
expected_sni=hostname if is_https else None,
)
# the FakeTransport is async, so we need to pump the reactor
self.reactor.advance(0)
# now there should be a pending request
self.assertEqual(len(http_server.requests), 1)
request = http_server.requests[0]
self.assertEqual(request.method, b"GET")
self.assertEqual(request.path, b"/" + path)
self.assertEqual(request.requestHeaders.getRawHeaders(b"host"), [hostname])
request.write(b"result")
request.finish()
self.reactor.advance(0)
resp = self.successResultOf(d)
body = self.successResultOf(treq.content(resp))
self.assertEqual(body, b"result")
def test_http_request(self):
agent = ProxyAgent(self.reactor)
self._test_request_direct_connection(agent, b"http", b"test.com", b"")
def test_https_request(self):
agent = ProxyAgent(self.reactor, contextFactory=get_test_https_policy())
self._test_request_direct_connection(agent, b"https", b"test.com", b"abc")
def test_http_request_use_proxy_empty_environment(self):
agent = ProxyAgent(self.reactor, use_proxy=True)
self._test_request_direct_connection(agent, b"http", b"test.com", b"")
@patch.dict(os.environ, {"http_proxy": "proxy.com:8888", "NO_PROXY": "test.com"})
def test_http_request_via_uppercase_no_proxy(self):
agent = ProxyAgent(self.reactor, use_proxy=True)
self._test_request_direct_connection(agent, b"http", b"test.com", b"")
@patch.dict(
os.environ, {"http_proxy": "proxy.com:8888", "no_proxy": "test.com,unused.com"}
)
def test_http_request_via_no_proxy(self):
agent = ProxyAgent(self.reactor, use_proxy=True)
self._test_request_direct_connection(agent, b"http", b"test.com", b"")
@patch.dict(
os.environ, {"https_proxy": "proxy.com", "no_proxy": "test.com,unused.com"}
)
def test_https_request_via_no_proxy(self):
agent = ProxyAgent(
self.reactor,
contextFactory=get_test_https_policy(),
use_proxy=True,
)
self._test_request_direct_connection(agent, b"https", b"test.com", b"abc")
@patch.dict(os.environ, {"http_proxy": "proxy.com:8888", "no_proxy": "*"})
def test_http_request_via_no_proxy_star(self):
agent = ProxyAgent(self.reactor, use_proxy=True)
self._test_request_direct_connection(agent, b"http", b"test.com", b"")
@patch.dict(os.environ, {"https_proxy": "proxy.com", "no_proxy": "*"})
def test_https_request_via_no_proxy_star(self):
agent = ProxyAgent(
self.reactor,
contextFactory=get_test_https_policy(),
use_proxy=True,
)
self._test_request_direct_connection(agent, b"https", b"test.com", b"abc")
@patch.dict(os.environ, {"http_proxy": "proxy.com:8888", "no_proxy": "unused.com"})
def test_http_request_via_proxy(self):
agent = ProxyAgent(self.reactor, use_proxy=True)
self.reactor.lookups["proxy.com"] = "1.2.3.5"
d = agent.request(b"GET", b"http://test.com")
# there should be a pending TCP connection
clients = self.reactor.tcpClients
self.assertEqual(len(clients), 1)
(host, port, client_factory, _timeout, _bindAddress) = clients[0]
self.assertEqual(host, "1.2.3.5")
self.assertEqual(port, 8888)
# make a test server, and wire up the client
http_server = self._make_connection(
client_factory, _get_test_protocol_factory()
)
# the FakeTransport is async, so we need to pump the reactor
self.reactor.advance(0)
# now there should be a pending request
self.assertEqual(len(http_server.requests), 1)
request = http_server.requests[0]
self.assertEqual(request.method, b"GET")
self.assertEqual(request.path, b"http://test.com")
self.assertEqual(request.requestHeaders.getRawHeaders(b"host"), [b"test.com"])
request.write(b"result")
request.finish()
self.reactor.advance(0)
resp = self.successResultOf(d)
body = self.successResultOf(treq.content(resp))
self.assertEqual(body, b"result")
@patch.dict(os.environ, {"https_proxy": "proxy.com", "no_proxy": "unused.com"})
def test_https_request_via_proxy(self):
"""Tests that TLS-encrypted requests can be made through a proxy"""
self._do_https_request_via_proxy(auth_credentials=None)
@patch.dict(
os.environ,
{"https_proxy": "bob:pinkponies@proxy.com", "no_proxy": "unused.com"},
)
def test_https_request_via_proxy_with_auth(self):
"""Tests that authenticated, TLS-encrypted requests can be made through a proxy"""
self._do_https_request_via_proxy(auth_credentials="bob:pinkponies")
def _do_https_request_via_proxy(
self,
auth_credentials: Optional[str] = None,
):
agent = ProxyAgent(
self.reactor,
contextFactory=get_test_https_policy(),
use_proxy=True,
)
self.reactor.lookups["proxy.com"] = "1.2.3.5"
d = agent.request(b"GET", b"https://test.com/abc")
# there should be a pending TCP connection
clients = self.reactor.tcpClients
self.assertEqual(len(clients), 1)
(host, port, client_factory, _timeout, _bindAddress) = clients[0]
self.assertEqual(host, "1.2.3.5")
self.assertEqual(port, 1080)
# make a test HTTP server, and wire up the client
proxy_server = self._make_connection(
client_factory, _get_test_protocol_factory()
)
# fish the transports back out so that we can do the old switcheroo
s2c_transport = proxy_server.transport
client_protocol = s2c_transport.other
c2s_transport = client_protocol.transport
# the FakeTransport is async, so we need to pump the reactor
self.reactor.advance(0)
# now there should be a pending CONNECT request
self.assertEqual(len(proxy_server.requests), 1)
request = proxy_server.requests[0]
self.assertEqual(request.method, b"CONNECT")
self.assertEqual(request.path, b"test.com:443")
# Check whether auth credentials have been supplied to the proxy
proxy_auth_header_values = request.requestHeaders.getRawHeaders(
b"Proxy-Authorization"
)
if auth_credentials is not None:
# Compute the correct header value for Proxy-Authorization
encoded_credentials = base64.b64encode(b"bob:pinkponies")
expected_header_value = b"Basic " + encoded_credentials
# Validate the header's value
self.assertIn(expected_header_value, proxy_auth_header_values)
else:
# Check that the Proxy-Authorization header has not been supplied to the proxy
self.assertIsNone(proxy_auth_header_values)
# tell the proxy server not to close the connection
proxy_server.persistent = True
# this just stops the http Request trying to do a chunked response
# request.setHeader(b"Content-Length", b"0")
request.finish()
# now we can replace the proxy channel with a new, SSL-wrapped HTTP channel
ssl_factory = _wrap_server_factory_for_tls(_get_test_protocol_factory())
ssl_protocol = ssl_factory.buildProtocol(None)
http_server = ssl_protocol.wrappedProtocol
ssl_protocol.makeConnection(
FakeTransport(client_protocol, self.reactor, ssl_protocol)
)
c2s_transport.other = ssl_protocol
self.reactor.advance(0)
server_name = ssl_protocol._tlsConnection.get_servername()
expected_sni = b"test.com"
self.assertEqual(
server_name,
expected_sni,
"Expected SNI %s but got %s" % (expected_sni, server_name),
)
# now there should be a pending request
self.assertEqual(len(http_server.requests), 1)
request = http_server.requests[0]
self.assertEqual(request.method, b"GET")
self.assertEqual(request.path, b"/abc")
self.assertEqual(request.requestHeaders.getRawHeaders(b"host"), [b"test.com"])
# Check that the destination server DID NOT receive proxy credentials
proxy_auth_header_values = request.requestHeaders.getRawHeaders(
b"Proxy-Authorization"
)
self.assertIsNone(proxy_auth_header_values)
request.write(b"result")
request.finish()
self.reactor.advance(0)
resp = self.successResultOf(d)
body = self.successResultOf(treq.content(resp))
self.assertEqual(body, b"result")
@patch.dict(os.environ, {"http_proxy": "proxy.com:8888"})
def test_http_request_via_proxy_with_blacklist(self):
# The blacklist includes the configured proxy IP.
agent = ProxyAgent(
BlacklistingReactorWrapper(
self.reactor, ip_whitelist=None, ip_blacklist=IPSet(["1.0.0.0/8"])
),
self.reactor,
use_proxy=True,
)
self.reactor.lookups["proxy.com"] = "1.2.3.5"
d = agent.request(b"GET", b"http://test.com")
# there should be a pending TCP connection
clients = self.reactor.tcpClients
self.assertEqual(len(clients), 1)
(host, port, client_factory, _timeout, _bindAddress) = clients[0]
self.assertEqual(host, "1.2.3.5")
self.assertEqual(port, 8888)
# make a test server, and wire up the client
http_server = self._make_connection(
client_factory, _get_test_protocol_factory()
)
# the FakeTransport is async, so we need to pump the reactor
self.reactor.advance(0)
# now there should be a pending request
self.assertEqual(len(http_server.requests), 1)
request = http_server.requests[0]
self.assertEqual(request.method, b"GET")
self.assertEqual(request.path, b"http://test.com")
self.assertEqual(request.requestHeaders.getRawHeaders(b"host"), [b"test.com"])
request.write(b"result")
request.finish()
self.reactor.advance(0)
resp = self.successResultOf(d)
body = self.successResultOf(treq.content(resp))
self.assertEqual(body, b"result")
@patch.dict(os.environ, {"HTTPS_PROXY": "proxy.com"})
def test_https_request_via_uppercase_proxy_with_blacklist(self):
# The blacklist includes the configured proxy IP.
agent = ProxyAgent(
BlacklistingReactorWrapper(
self.reactor, ip_whitelist=None, ip_blacklist=IPSet(["1.0.0.0/8"])
),
self.reactor,
contextFactory=get_test_https_policy(),
use_proxy=True,
)
self.reactor.lookups["proxy.com"] = "1.2.3.5"
d = agent.request(b"GET", b"https://test.com/abc")
# there should be a pending TCP connection
clients = self.reactor.tcpClients
self.assertEqual(len(clients), 1)
(host, port, client_factory, _timeout, _bindAddress) = clients[0]
self.assertEqual(host, "1.2.3.5")
self.assertEqual(port, 1080)
# make a test HTTP server, and wire up the client
proxy_server = self._make_connection(
client_factory, _get_test_protocol_factory()
)
# fish the transports back out so that we can do the old switcheroo
s2c_transport = proxy_server.transport
client_protocol = s2c_transport.other
c2s_transport = client_protocol.transport
# the FakeTransport is async, so we need to pump the reactor
self.reactor.advance(0)
# now there should be a pending CONNECT request
self.assertEqual(len(proxy_server.requests), 1)
request = proxy_server.requests[0]
self.assertEqual(request.method, b"CONNECT")
self.assertEqual(request.path, b"test.com:443")
# tell the proxy server not to close the connection
proxy_server.persistent = True
# this just stops the http Request trying to do a chunked response
# request.setHeader(b"Content-Length", b"0")
request.finish()
# now we can replace the proxy channel with a new, SSL-wrapped HTTP channel
ssl_factory = _wrap_server_factory_for_tls(_get_test_protocol_factory())
ssl_protocol = ssl_factory.buildProtocol(None)
http_server = ssl_protocol.wrappedProtocol
ssl_protocol.makeConnection(
FakeTransport(client_protocol, self.reactor, ssl_protocol)
)
c2s_transport.other = ssl_protocol
self.reactor.advance(0)
server_name = ssl_protocol._tlsConnection.get_servername()
expected_sni = b"test.com"
self.assertEqual(
server_name,
expected_sni,
"Expected SNI %s but got %s" % (expected_sni, server_name),
)
# now there should be a pending request
self.assertEqual(len(http_server.requests), 1)
request = http_server.requests[0]
self.assertEqual(request.method, b"GET")
self.assertEqual(request.path, b"/abc")
self.assertEqual(request.requestHeaders.getRawHeaders(b"host"), [b"test.com"])
request.write(b"result")
request.finish()
self.reactor.advance(0)
resp = self.successResultOf(d)
body = self.successResultOf(treq.content(resp))
self.assertEqual(body, b"result")
def _wrap_server_factory_for_tls(factory, sanlist=None):
"""Wrap an existing Protocol Factory with a test TLSMemoryBIOFactory
The resultant factory will create a TLS server which presents a certificate
signed by our test CA, valid for the domains in `sanlist`
Args:
factory (interfaces.IProtocolFactory): protocol factory to wrap
sanlist (iterable[bytes]): list of domains the cert should be valid for
Returns:
interfaces.IProtocolFactory
"""
if sanlist is None:
sanlist = [b"DNS:test.com"]
connection_creator = TestServerTLSConnectionFactory(sanlist=sanlist)
return TLSMemoryBIOFactory(
connection_creator, isClient=False, wrappedFactory=factory
)
def _get_test_protocol_factory():
"""Get a protocol Factory which will build an HTTPChannel
Returns:
interfaces.IProtocolFactory
"""
server_factory = Factory.forProtocol(HTTPChannel)
# Request.finish expects the factory to have a 'log' method.
server_factory.log = _log_request
return server_factory
def _log_request(request):
"""Implements Factory.log, which is expected by Request.finish"""
logger.info("Completed request %s", request)