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support federation queries through http connect proxy (#10475)

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Signed-off-by: Marcus Hoffmann <bubu@bubu1.eu>
Signed-off-by: Dirk Klimpel dirk@klimpel.org
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Dirk Klimpel 2021-08-11 16:34:59 +02:00 committed by GitHub
parent 8c654b7309
commit 339c3918e1
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9 changed files with 557 additions and 193 deletions
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1
changelog.d/10475.feature Normal file
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@ -0,0 +1 @@
Add support for sending federation requests through a proxy. Contributed by @Bubu and @dklimpel.

6
docs/setup/forward_proxy.md
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@ -45,18 +45,18 @@ The proxy will be **used** for:
- recaptcha validation
- CAS auth validation
- OpenID Connect
- Outbound federation
- Federation (checking public key revocation)
- Fetching public keys of other servers
- Downloading remote media
It will **not be used** for:
- Application Services
- Identity servers
- Outbound federation
- In worker configurations
- connections between workers
- connections from workers to Redis
- Fetching public keys of other servers
- Downloading remote media
## Troubleshooting

27
docs/upgrade.md
View file

@ -86,6 +86,33 @@ process, for example:
```
# Upgrading to v1.xx.0
## Add support for routing outbound HTTP requests via a proxy for federation
Since Synapse 1.6.0 (2019-11-26) you can set a proxy for outbound HTTP requests via
http_proxy/https_proxy environment variables. This proxy was set for:
- push
- url previews
- phone-home stats
- recaptcha validation
- CAS auth validation
- OpenID Connect
- Federation (checking public key revocation)
In this version we have added support for outbound requests for:
- Outbound federation
- Downloading remote media
- Fetching public keys of other servers
These requests use the same proxy configuration. If you have a proxy configuration we
recommend to verify the configuration. It may be necessary to adjust the `no_proxy`
environment variable.
See [using a forward proxy with Synapse documentation](setup/forward_proxy.md) for
details.
# Upgrading to v1.39.0
## Deprecation of the current third-party rules module interface

68
synapse/http/connectproxyclient.py
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@ -12,8 +12,11 @@
# See the License for the specific language governing permissions and
# limitations under the License.
import base64
import logging
from typing import Optional
import attr
from zope.interface import implementer
from twisted.internet import defer, protocol
@ -21,7 +24,6 @@ from twisted.internet.error import ConnectError
from twisted.internet.interfaces import IReactorCore, IStreamClientEndpoint
from twisted.internet.protocol import ClientFactory, Protocol, connectionDone
from twisted.web import http
from twisted.web.http_headers import Headers
logger = logging.getLogger(__name__)
@ -30,6 +32,22 @@ class ProxyConnectError(ConnectError):
pass
@attr.s
class ProxyCredentials:
username_password = attr.ib(type=bytes)
def as_proxy_authorization_value(self) -> bytes:
"""
Return the value for a Proxy-Authorization header (i.e. 'Basic abdef==').
Returns:
A transformation of the authentication string the encoded value for
a Proxy-Authorization header.
"""
# Encode as base64 and prepend the authorization type
return b"Basic " + base64.encodebytes(self.username_password)
@implementer(IStreamClientEndpoint)
class HTTPConnectProxyEndpoint:
"""An Endpoint implementation which will send a CONNECT request to an http proxy
@ -46,7 +64,7 @@ class HTTPConnectProxyEndpoint:
proxy_endpoint: the endpoint to use to connect to the proxy
host: hostname that we want to CONNECT to
port: port that we want to connect to
headers: Extra HTTP headers to include in the CONNECT request
proxy_creds: credentials to authenticate at proxy
"""
def __init__(
@ -55,20 +73,20 @@ class HTTPConnectProxyEndpoint:
proxy_endpoint: IStreamClientEndpoint,
host: bytes,
port: int,
headers: Headers,
proxy_creds: Optional[ProxyCredentials],
):
self._reactor = reactor
self._proxy_endpoint = proxy_endpoint
self._host = host
self._port = port
self._headers = headers
self._proxy_creds = proxy_creds
def __repr__(self):
return "<HTTPConnectProxyEndpoint %s>" % (self._proxy_endpoint,)
def connect(self, protocolFactory: ClientFactory):
f = HTTPProxiedClientFactory(
self._host, self._port, protocolFactory, self._headers
self._host, self._port, protocolFactory, self._proxy_creds
)
d = self._proxy_endpoint.connect(f)
# once the tcp socket connects successfully, we need to wait for the
@ -87,7 +105,7 @@ class HTTPProxiedClientFactory(protocol.ClientFactory):
dst_host: hostname that we want to CONNECT to
dst_port: port that we want to connect to
wrapped_factory: The original Factory
headers: Extra HTTP headers to include in the CONNECT request
proxy_creds: credentials to authenticate at proxy
"""
def __init__(
@ -95,12 +113,12 @@ class HTTPProxiedClientFactory(protocol.ClientFactory):
dst_host: bytes,
dst_port: int,
wrapped_factory: ClientFactory,
headers: Headers,
proxy_creds: Optional[ProxyCredentials],
):
self.dst_host = dst_host
self.dst_port = dst_port
self.wrapped_factory = wrapped_factory
self.headers = headers
self.proxy_creds = proxy_creds
self.on_connection = defer.Deferred()
def startedConnecting(self, connector):
@ -114,7 +132,7 @@ class HTTPProxiedClientFactory(protocol.ClientFactory):
self.dst_port,
wrapped_protocol,
self.on_connection,
self.headers,
self.proxy_creds,
)
def clientConnectionFailed(self, connector, reason):
@ -145,7 +163,7 @@ class HTTPConnectProtocol(protocol.Protocol):
connected_deferred: a Deferred which will be callbacked with
wrapped_protocol when the CONNECT completes
headers: Extra HTTP headers to include in the CONNECT request
proxy_creds: credentials to authenticate at proxy
"""
def __init__(
@ -154,16 +172,16 @@ class HTTPConnectProtocol(protocol.Protocol):
port: int,
wrapped_protocol: Protocol,
connected_deferred: defer.Deferred,
headers: Headers,
proxy_creds: Optional[ProxyCredentials],
):
self.host = host
self.port = port
self.wrapped_protocol = wrapped_protocol
self.connected_deferred = connected_deferred
self.headers = headers
self.proxy_creds = proxy_creds
self.http_setup_client = HTTPConnectSetupClient(
self.host, self.port, self.headers
self.host, self.port, self.proxy_creds
)
self.http_setup_client.on_connected.addCallback(self.proxyConnected)
@ -205,30 +223,38 @@ class HTTPConnectSetupClient(http.HTTPClient):
Args:
host: The hostname to send in the CONNECT message
port: The port to send in the CONNECT message
headers: Extra headers to send with the CONNECT message
proxy_creds: credentials to authenticate at proxy
"""
def __init__(self, host: bytes, port: int, headers: Headers):
def __init__(
self,
host: bytes,
port: int,
proxy_creds: Optional[ProxyCredentials],
):
self.host = host
self.port = port
self.headers = headers
self.proxy_creds = proxy_creds
self.on_connected = defer.Deferred()
def connectionMade(self):
logger.debug("Connected to proxy, sending CONNECT")
self.sendCommand(b"CONNECT", b"%s:%d" % (self.host, self.port))
# Send any additional specified headers
for name, values in self.headers.getAllRawHeaders():
for value in values:
self.sendHeader(name, value)
# Determine whether we need to set Proxy-Authorization headers
if self.proxy_creds:
# Set a Proxy-Authorization header
self.sendHeader(
b"Proxy-Authorization",
self.proxy_creds.as_proxy_authorization_value(),
)
self.endHeaders()
def handleStatus(self, version: bytes, status: bytes, message: bytes):
logger.debug("Got Status: %s %s %s", status, message, version)
if status != b"200":
raise ProxyConnectError("Unexpected status on CONNECT: %s" % status)
raise ProxyConnectError(f"Unexpected status on CONNECT: {status!s}")
def handleEndHeaders(self):
logger.debug("End Headers")

100
synapse/http/federation/matrix_federation_agent.py
View file

@ -14,6 +14,10 @@
import logging
import urllib.parse
from typing import Any, Generator, List, Optional
from urllib.request import ( # type: ignore[attr-defined]
getproxies_environment,
proxy_bypass_environment,
)
from netaddr import AddrFormatError, IPAddress, IPSet
from zope.interface import implementer
@ -30,9 +34,12 @@ from twisted.web.http_headers import Headers
from twisted.web.iweb import IAgent, IAgentEndpointFactory, IBodyProducer, IResponse
from synapse.crypto.context_factory import FederationPolicyForHTTPS
from synapse.http.client import BlacklistingAgentWrapper
from synapse.http import proxyagent
from synapse.http.client import BlacklistingAgentWrapper, BlacklistingReactorWrapper
from synapse.http.connectproxyclient import HTTPConnectProxyEndpoint
from synapse.http.federation.srv_resolver import Server, SrvResolver
from synapse.http.federation.well_known_resolver import WellKnownResolver
from synapse.http.proxyagent import ProxyAgent
from synapse.logging.context import make_deferred_yieldable, run_in_background
from synapse.types import ISynapseReactor
from synapse.util import Clock
@ -57,6 +64,14 @@ class MatrixFederationAgent:
user_agent:
The user agent header to use for federation requests.
ip_whitelist: Allowed IP addresses.
ip_blacklist: Disallowed IP addresses.
proxy_reactor: twisted reactor to use for connections to the proxy server
reactor might have some blacklisting applied (i.e. for DNS queries),
but we need unblocked access to the proxy.
_srv_resolver:
SrvResolver implementation to use for looking up SRV records. None
to use a default implementation.
@ -71,11 +86,18 @@ class MatrixFederationAgent:
reactor: ISynapseReactor,
tls_client_options_factory: Optional[FederationPolicyForHTTPS],
user_agent: bytes,
ip_whitelist: IPSet,
ip_blacklist: IPSet,
_srv_resolver: Optional[SrvResolver] = None,
_well_known_resolver: Optional[WellKnownResolver] = None,
):
self._reactor = reactor
# proxy_reactor is not blacklisted
proxy_reactor = reactor
# We need to use a DNS resolver which filters out blacklisted IP
# addresses, to prevent DNS rebinding.
reactor = BlacklistingReactorWrapper(reactor, ip_whitelist, ip_blacklist)
self._clock = Clock(reactor)
self._pool = HTTPConnectionPool(reactor)
self._pool.retryAutomatically = False
@ -83,24 +105,27 @@ class MatrixFederationAgent:
self._pool.cachedConnectionTimeout = 2 * 60
self._agent = Agent.usingEndpointFactory(
self._reactor,
reactor,
MatrixHostnameEndpointFactory(
reactor, tls_client_options_factory, _srv_resolver
reactor,
proxy_reactor,
tls_client_options_factory,
_srv_resolver,
),
pool=self._pool,
)
self.user_agent = user_agent
if _well_known_resolver is None:
# Note that the name resolver has already been wrapped in a
# IPBlacklistingResolver by MatrixFederationHttpClient.
_well_known_resolver = WellKnownResolver(
self._reactor,
reactor,
agent=BlacklistingAgentWrapper(
Agent(
self._reactor,
ProxyAgent(
reactor,
proxy_reactor,
pool=self._pool,
contextFactory=tls_client_options_factory,
use_proxy=True,
),
ip_blacklist=ip_blacklist,
),
@ -200,10 +225,12 @@ class MatrixHostnameEndpointFactory:
def __init__(
self,
reactor: IReactorCore,
proxy_reactor: IReactorCore,
tls_client_options_factory: Optional[FederationPolicyForHTTPS],
srv_resolver: Optional[SrvResolver],
):
self._reactor = reactor
self._proxy_reactor = proxy_reactor
self._tls_client_options_factory = tls_client_options_factory
if srv_resolver is None:
@ -211,9 +238,10 @@ class MatrixHostnameEndpointFactory:
self._srv_resolver = srv_resolver
def endpointForURI(self, parsed_uri):
def endpointForURI(self, parsed_uri: URI):
return MatrixHostnameEndpoint(
self._reactor,
self._proxy_reactor,
self._tls_client_options_factory,
self._srv_resolver,
parsed_uri,
@ -227,23 +255,45 @@ class MatrixHostnameEndpoint:
Args:
reactor: twisted reactor to use for underlying requests
proxy_reactor: twisted reactor to use for connections to the proxy server.
'reactor' might have some blacklisting applied (i.e. for DNS queries),
but we need unblocked access to the proxy.
tls_client_options_factory:
factory to use for fetching client tls options, or none to disable TLS.
srv_resolver: The SRV resolver to use
parsed_uri: The parsed URI that we're wanting to connect to.
Raises:
ValueError if the environment variables contain an invalid proxy specification.
RuntimeError if no tls_options_factory is given for a https connection
"""
def __init__(
self,
reactor: IReactorCore,
proxy_reactor: IReactorCore,
tls_client_options_factory: Optional[FederationPolicyForHTTPS],
srv_resolver: SrvResolver,
parsed_uri: URI,
):
self._reactor = reactor
self._parsed_uri = parsed_uri
# http_proxy is not needed because federation is always over TLS
proxies = getproxies_environment()
https_proxy = proxies["https"].encode() if "https" in proxies else None
self.no_proxy = proxies["no"] if "no" in proxies else None
# endpoint and credentials to use to connect to the outbound https proxy, if any.
(
self._https_proxy_endpoint,
self._https_proxy_creds,
) = proxyagent.http_proxy_endpoint(
https_proxy,
proxy_reactor,
tls_client_options_factory,
)
# set up the TLS connection params
#
# XXX disabling TLS is really only supported here for the benefit of the
@ -273,9 +323,33 @@ class MatrixHostnameEndpoint:
host = server.host
port = server.port
should_skip_proxy = False
if self.no_proxy is not None:
should_skip_proxy = proxy_bypass_environment(
host.decode(),
proxies={"no": self.no_proxy},
)
endpoint: IStreamClientEndpoint
try:
logger.debug("Connecting to %s:%i", host.decode("ascii"), port)
endpoint = HostnameEndpoint(self._reactor, host, port)
if self._https_proxy_endpoint and not should_skip_proxy:
logger.debug(
"Connecting to %s:%i via %s",
host.decode("ascii"),
port,
self._https_proxy_endpoint,
)
endpoint = HTTPConnectProxyEndpoint(
self._reactor,
self._https_proxy_endpoint,
host,
port,
proxy_creds=self._https_proxy_creds,
)
else:
logger.debug("Connecting to %s:%i", host.decode("ascii"), port)
# not using a proxy
endpoint = HostnameEndpoint(self._reactor, host, port)
if self._tls_options:
endpoint = wrapClientTLS(self._tls_options, endpoint)
result = await make_deferred_yieldable(

12
synapse/http/matrixfederationclient.py
View file

@ -59,7 +59,6 @@ from synapse.api.errors import (
from synapse.http import QuieterFileBodyProducer
from synapse.http.client import (
BlacklistingAgentWrapper,
BlacklistingReactorWrapper,
BodyExceededMaxSize,
ByteWriteable,
encode_query_args,
@ -69,7 +68,7 @@ from synapse.http.federation.matrix_federation_agent import MatrixFederationAgen
from synapse.logging import opentracing
from synapse.logging.context import make_deferred_yieldable
from synapse.logging.opentracing import set_tag, start_active_span, tags
from synapse.types import ISynapseReactor, JsonDict
from synapse.types import JsonDict
from synapse.util import json_decoder
from synapse.util.async_helpers import timeout_deferred
from synapse.util.metrics import Measure
@ -325,13 +324,7 @@ class MatrixFederationHttpClient:
self.signing_key = hs.signing_key
self.server_name = hs.hostname
# We need to use a DNS resolver which filters out blacklisted IP
# addresses, to prevent DNS rebinding.
self.reactor: ISynapseReactor = BlacklistingReactorWrapper(
hs.get_reactor(),
hs.config.federation_ip_range_whitelist,
hs.config.federation_ip_range_blacklist,
)
self.reactor = hs.get_reactor()
user_agent = hs.version_string
if hs.config.user_agent_suffix:
@ -342,6 +335,7 @@ class MatrixFederationHttpClient:
self.reactor,
tls_client_options_factory,
user_agent,
hs.config.federation_ip_range_whitelist,
hs.config.federation_ip_range_blacklist,
)

51
synapse/http/proxyagent.py
View file

@ -11,7 +11,6 @@
# 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 re
from typing import Any, Dict, Optional, Tuple
@ -21,7 +20,6 @@ from urllib.request import ( # type: ignore[attr-defined]
proxy_bypass_environment,
)
import attr
from zope.interface import implementer
from twisted.internet import defer
@ -38,7 +36,7 @@ from twisted.web.error import SchemeNotSupported
from twisted.web.http_headers import Headers
from twisted.web.iweb import IAgent, IBodyProducer, IPolicyForHTTPS
from synapse.http.connectproxyclient import HTTPConnectProxyEndpoint
from synapse.http.connectproxyclient import HTTPConnectProxyEndpoint, ProxyCredentials
from synapse.types import ISynapseReactor
logger = logging.getLogger(__name__)
@ -46,22 +44,6 @@ logger = logging.getLogger(__name__)
_VALID_URI = re.compile(br"\A[\x21-\x7e]+\Z")
@attr.s
class ProxyCredentials:
username_password = attr.ib(type=bytes)
def as_proxy_authorization_value(self) -> bytes:
"""
Return the value for a Proxy-Authorization header (i.e. 'Basic abdef==').
Returns:
A transformation of the authentication string the encoded value for
a Proxy-Authorization header.
"""
# Encode as base64 and prepend the authorization type
return b"Basic " + base64.encodebytes(self.username_password)
@implementer(IAgent)
class ProxyAgent(_AgentBase):
"""An Agent implementation which will use an HTTP proxy if one was requested
@ -95,6 +77,7 @@ class ProxyAgent(_AgentBase):
Raises:
ValueError if use_proxy is set and the environment variables
contain an invalid proxy specification.
RuntimeError if no tls_options_factory is given for a https connection
"""
def __init__(
@ -131,11 +114,11 @@ class ProxyAgent(_AgentBase):
https_proxy = proxies["https"].encode() if "https" in proxies else None
no_proxy = proxies["no"] if "no" in proxies else None
self.http_proxy_endpoint, self.http_proxy_creds = _http_proxy_endpoint(
self.http_proxy_endpoint, self.http_proxy_creds = http_proxy_endpoint(
http_proxy, self.proxy_reactor, contextFactory, **self._endpoint_kwargs
)
self.https_proxy_endpoint, self.https_proxy_creds = _http_proxy_endpoint(
self.https_proxy_endpoint, self.https_proxy_creds = http_proxy_endpoint(
https_proxy, self.proxy_reactor, contextFactory, **self._endpoint_kwargs
)
@ -224,22 +207,12 @@ class ProxyAgent(_AgentBase):
and self.https_proxy_endpoint
and not should_skip_proxy
):
connect_headers = Headers()
# Determine whether we need to set Proxy-Authorization headers
if self.https_proxy_creds:
# Set a Proxy-Authorization header
connect_headers.addRawHeader(
b"Proxy-Authorization",
self.https_proxy_creds.as_proxy_authorization_value(),
)
endpoint = HTTPConnectProxyEndpoint(
self.proxy_reactor,
self.https_proxy_endpoint,
parsed_uri.host,
parsed_uri.port,
headers=connect_headers,
self.https_proxy_creds,
)
else:
# not using a proxy
@ -268,10 +241,10 @@ class ProxyAgent(_AgentBase):
)
def _http_proxy_endpoint(
def http_proxy_endpoint(
proxy: Optional[bytes],
reactor: IReactorCore,
tls_options_factory: IPolicyForHTTPS,
tls_options_factory: Optional[IPolicyForHTTPS],
**kwargs,
) -> Tuple[Optional[IStreamClientEndpoint], Optional[ProxyCredentials]]:
"""Parses an http proxy setting and returns an endpoint for the proxy
@ -294,6 +267,7 @@ def _http_proxy_endpoint(
Raise:
ValueError if proxy has no hostname or unsupported scheme.
RuntimeError if no tls_options_factory is given for a https connection
"""
if proxy is None:
return None, None
@ -305,8 +279,13 @@ def _http_proxy_endpoint(
proxy_endpoint = HostnameEndpoint(reactor, host, port, **kwargs)
if scheme == b"https":
tls_options = tls_options_factory.creatorForNetloc(host, port)
proxy_endpoint = wrapClientTLS(tls_options, proxy_endpoint)
if tls_options_factory:
tls_options = tls_options_factory.creatorForNetloc(host, port)
proxy_endpoint = wrapClientTLS(tls_options, proxy_endpoint)
else:
raise RuntimeError(
f"No TLS options for a https connection via proxy {proxy!s}"
)
return proxy_endpoint, credentials

410
tests/http/federation/test_matrix_federation_agent.py
View file

@ -11,9 +11,11 @@
# 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
from typing import Optional
from unittest.mock import Mock
import os
from typing import Iterable, Optional
from unittest.mock import Mock, patch
import treq
from netaddr import IPSet
@ -22,11 +24,12 @@ from zope.interface import implementer
from twisted.internet import defer
from twisted.internet._sslverify import ClientTLSOptions, OpenSSLCertificateOptions
from twisted.internet.interfaces import IProtocolFactory
from twisted.internet.protocol import Factory
from twisted.protocols.tls import TLSMemoryBIOFactory
from twisted.protocols.tls import TLSMemoryBIOFactory, TLSMemoryBIOProtocol
from twisted.web._newclient import ResponseNeverReceived
from twisted.web.client import Agent
from twisted.web.http import HTTPChannel
from twisted.web.http import HTTPChannel, Request
from twisted.web.http_headers import Headers
from twisted.web.iweb import IPolicyForHTTPS
@ -49,24 +52,6 @@ from tests.utils import default_config
logger = logging.getLogger(__name__)
test_server_connection_factory = None
def get_connection_factory():
# this needs to happen once, but not until we are ready to run the first test
global test_server_connection_factory
if test_server_connection_factory is None:
test_server_connection_factory = TestServerTLSConnectionFactory(
sanlist=[
b"DNS:testserv",
b"DNS:target-server",
b"DNS:xn--bcher-kva.com",
b"IP:1.2.3.4",
b"IP:::1",
]
)
return test_server_connection_factory
# Once Async Mocks or lambdas are supported this can go away.
def generate_resolve_service(result):
@ -100,24 +85,38 @@ class MatrixFederationAgentTests(unittest.TestCase):
had_well_known_cache=self.had_well_known_cache,
)
self.agent = MatrixFederationAgent(
reactor=self.reactor,
tls_client_options_factory=self.tls_factory,
user_agent="test-agent", # Note that this is unused since _well_known_resolver is provided.
ip_blacklist=IPSet(),
_srv_resolver=self.mock_resolver,
_well_known_resolver=self.well_known_resolver,
)
def _make_connection(self, client_factory, expected_sni):
def _make_connection(
self,
client_factory: IProtocolFactory,
ssl: bool = True,
expected_sni: bytes = None,
tls_sanlist: Optional[Iterable[bytes]] = None,
) -> HTTPChannel:
"""Builds a test server, and completes the outgoing client connection
Args:
client_factory: the the factory that the
application is trying to use to make the outbound connection. We will
invoke it to build the client Protocol
ssl: If true, we will expect an ssl connection and wrap
server_factory with a TLSMemoryBIOFactory
False is set only for when proxy expect http connection.
Otherwise federation requests use always https.
expected_sni: the expected SNI value
tls_sanlist: list of SAN entries for the TLS cert presented by the server.
Returns:
HTTPChannel: the test server
the server Protocol returned by server_factory
"""
# build the test server
server_tls_protocol = _build_test_server(get_connection_factory())
server_factory = _get_test_protocol_factory()
if ssl:
server_factory = _wrap_server_factory_for_tls(server_factory, tls_sanlist)
server_protocol = server_factory.buildProtocol(None)
# now, tell the client protocol factory to build the client protocol (it will be a
# _WrappingProtocol, around a TLSMemoryBIOProtocol, around an
@ -128,35 +127,39 @@ class MatrixFederationAgentTests(unittest.TestCase):
# stubbing that out here.
client_protocol = client_factory.buildProtocol(None)
client_protocol.makeConnection(
FakeTransport(server_tls_protocol, self.reactor, client_protocol)
FakeTransport(server_protocol, self.reactor, client_protocol)
)
# tell the server tls protocol to send its stuff back to the client, too
server_tls_protocol.makeConnection(
FakeTransport(client_protocol, self.reactor, server_tls_protocol)
# tell the server protocol to send its stuff back to the client, too
server_protocol.makeConnection(
FakeTransport(client_protocol, self.reactor, server_protocol)
)
# grab a hold of the TLS connection, in case it gets torn down
server_tls_connection = server_tls_protocol._tlsConnection
if ssl:
# fish the test server back out of the server-side TLS protocol.
http_protocol = server_protocol.wrappedProtocol
# grab a hold of the TLS connection, in case it gets torn down
tls_connection = server_protocol._tlsConnection
else:
http_protocol = server_protocol
tls_connection = None
# fish the test server back out of the server-side TLS protocol.
http_protocol = server_tls_protocol.wrappedProtocol
# give the reactor a pump to get the TLS juices flowing.
self.reactor.pump((0.1,))
# give the reactor a pump to get the TLS juices flowing (if needed)
self.reactor.advance(0)
# check the SNI
server_name = server_tls_connection.get_servername()
self.assertEqual(
server_name,
expected_sni,
"Expected SNI %s but got %s" % (expected_sni, server_name),
)
if expected_sni is not None:
server_name = tls_connection.get_servername()
self.assertEqual(
server_name,
expected_sni,
f"Expected SNI {expected_sni!s} but got {server_name!s}",
)
return http_protocol
@defer.inlineCallbacks
def _make_get_request(self, uri):
def _make_get_request(self, uri: bytes):
"""
Sends a simple GET request via the agent, and checks its logcontext management
"""
@ -180,20 +183,20 @@ class MatrixFederationAgentTests(unittest.TestCase):
def _handle_well_known_connection(
self,
client_factory,
expected_sni,
content,
client_factory: IProtocolFactory,
expected_sni: bytes,
content: bytes,
response_headers: Optional[dict] = None,
):
) -> HTTPChannel:
"""Handle an outgoing HTTPs connection: wire it up to a server, check that the
request is for a .well-known, and send the response.
Args:
client_factory (IProtocolFactory): outgoing connection
expected_sni (bytes): SNI that we expect the outgoing connection to send
content (bytes): content to send back as the .well-known
client_factory: outgoing connection
expected_sni: SNI that we expect the outgoing connection to send
content: content to send back as the .well-known
Returns:
HTTPChannel: server impl
server impl
"""
# make the connection for .well-known
well_known_server = self._make_connection(
@ -209,7 +212,10 @@ class MatrixFederationAgentTests(unittest.TestCase):
return well_known_server
def _send_well_known_response(
self, request, content, headers: Optional[dict] = None
self,
request: Request,
content: bytes,
headers: Optional[dict] = None,
):
"""Check that an incoming request looks like a valid .well-known request, and
send back the response.
@ -225,10 +231,37 @@ class MatrixFederationAgentTests(unittest.TestCase):
self.reactor.pump((0.1,))
def _make_agent(self) -> MatrixFederationAgent:
"""
If a proxy server is set, the MatrixFederationAgent must be created again
because it is created too early during setUp
"""
return MatrixFederationAgent(
reactor=self.reactor,
tls_client_options_factory=self.tls_factory,
user_agent="test-agent", # Note that this is unused since _well_known_resolver is provided.
ip_whitelist=IPSet(),
ip_blacklist=IPSet(),
_srv_resolver=self.mock_resolver,
_well_known_resolver=self.well_known_resolver,
)
def test_get(self):
"""
happy-path test of a GET request with an explicit port
"""
"""happy-path test of a GET request with an explicit port"""
self._do_get()
@patch.dict(
os.environ,
{"https_proxy": "proxy.com", "no_proxy": "testserv"},
)
def test_get_bypass_proxy(self):
"""test of a GET request with an explicit port and bypass proxy"""
self._do_get()
def _do_get(self):
"""test of a GET request with an explicit port"""
self.agent = self._make_agent()
self.reactor.lookups["testserv"] = "1.2.3.4"
test_d = self._make_get_request(b"matrix://testserv:8448/foo/bar")
@ -282,10 +315,188 @@ class MatrixFederationAgentTests(unittest.TestCase):
json = self.successResultOf(treq.json_content(response))
self.assertEqual(json, {"a": 1})
@patch.dict(
os.environ, {"https_proxy": "http://proxy.com", "no_proxy": "unused.com"}
)
def test_get_via_http_proxy(self):
"""test for federation request through a http proxy"""
self._do_get_via_proxy(expect_proxy_ssl=False, expected_auth_credentials=None)
@patch.dict(
os.environ,
{"https_proxy": "http://user:pass@proxy.com", "no_proxy": "unused.com"},
)
def test_get_via_http_proxy_with_auth(self):
"""test for federation request through a http proxy with authentication"""
self._do_get_via_proxy(
expect_proxy_ssl=False, expected_auth_credentials=b"user:pass"
)
@patch.dict(
os.environ, {"https_proxy": "https://proxy.com", "no_proxy": "unused.com"}
)
def test_get_via_https_proxy(self):
"""test for federation request through a https proxy"""
self._do_get_via_proxy(expect_proxy_ssl=True, expected_auth_credentials=None)
@patch.dict(
os.environ,
{"https_proxy": "https://user:pass@proxy.com", "no_proxy": "unused.com"},
)
def test_get_via_https_proxy_with_auth(self):
"""test for federation request through a https proxy with authentication"""
self._do_get_via_proxy(
expect_proxy_ssl=True, expected_auth_credentials=b"user:pass"
)
def _do_get_via_proxy(
self,
expect_proxy_ssl: bool = False,
expected_auth_credentials: Optional[bytes] = None,
):
"""Send a https federation request via an agent and check that it is correctly
received at the proxy and client. The proxy can use either http or https.
Args:
expect_proxy_ssl: True if we expect the request to connect to the proxy via https.
expected_auth_credentials: credentials we expect to be presented to authenticate at the proxy
"""
self.agent = self._make_agent()
self.reactor.lookups["testserv"] = "1.2.3.4"
self.reactor.lookups["proxy.com"] = "9.9.9.9"
test_d = self._make_get_request(b"matrix://testserv:8448/foo/bar")
# 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, client_factory, _timeout, _bindAddress) = clients[0]
# make sure we are connecting to the proxy
self.assertEqual(host, "9.9.9.9")
self.assertEqual(port, 1080)
# make a test server to act as the proxy, and wire up the client
proxy_server = self._make_connection(
client_factory,
ssl=expect_proxy_ssl,
tls_sanlist=[b"DNS:proxy.com"] if expect_proxy_ssl else None,
expected_sni=b"proxy.com" if expect_proxy_ssl else None,
)
assert isinstance(proxy_server, HTTPChannel)
# 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"testserv:8448")
# Check whether auth credentials have been supplied to the proxy
proxy_auth_header_values = request.requestHeaders.getRawHeaders(
b"Proxy-Authorization"
)
if expected_auth_credentials is not None:
# Compute the correct header value for Proxy-Authorization
encoded_credentials = base64.b64encode(expected_auth_credentials)
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
request.finish()
# now we make another test server to act as the upstream HTTP server.
server_ssl_protocol = _wrap_server_factory_for_tls(
_get_test_protocol_factory()
).buildProtocol(None)
# Tell the HTTP server to send outgoing traffic back via the proxy's transport.
proxy_server_transport = proxy_server.transport
server_ssl_protocol.makeConnection(proxy_server_transport)
# ... and replace the protocol on the proxy's transport with the
# TLSMemoryBIOProtocol for the test server, so that incoming traffic
# to the proxy gets sent over to the HTTP(s) server.
# See also comment at `_do_https_request_via_proxy`
# in ../test_proxyagent.py for more details
if expect_proxy_ssl:
assert isinstance(proxy_server_transport, TLSMemoryBIOProtocol)
proxy_server_transport.wrappedProtocol = server_ssl_protocol
else:
assert isinstance(proxy_server_transport, FakeTransport)
client_protocol = proxy_server_transport.other
c2s_transport = client_protocol.transport
c2s_transport.other = server_ssl_protocol
self.reactor.advance(0)
server_name = server_ssl_protocol._tlsConnection.get_servername()
expected_sni = b"testserv"
self.assertEqual(
server_name,
expected_sni,
f"Expected SNI {expected_sni!s} but got {server_name!s}",
)
# now there should be a pending request
http_server = server_ssl_protocol.wrappedProtocol
self.assertEqual(len(http_server.requests), 1)
request = http_server.requests[0]
self.assertEqual(request.method, b"GET")
self.assertEqual(request.path, b"/foo/bar")
self.assertEqual(
request.requestHeaders.getRawHeaders(b"host"), [b"testserv:8448"]
)
self.assertEqual(
request.requestHeaders.getRawHeaders(b"user-agent"), [b"test-agent"]
)
# Check that the destination server DID NOT receive proxy credentials
self.assertIsNone(request.requestHeaders.getRawHeaders(b"Proxy-Authorization"))
content = request.content.read()
self.assertEqual(content, b"")
# Deferred is still without a result
self.assertNoResult(test_d)
# send the headers
request.responseHeaders.setRawHeaders(b"Content-Type", [b"application/json"])
request.write("")
self.reactor.pump((0.1,))
response = self.successResultOf(test_d)
# that should give us a Response object
self.assertEqual(response.code, 200)
# Send the body
request.write('{ "a": 1 }'.encode("ascii"))
request.finish()
self.reactor.pump((0.1,))
# check it can be read
json = self.successResultOf(treq.json_content(response))
self.assertEqual(json, {"a": 1})
def test_get_ip_address(self):
"""
Test the behaviour when the server name contains an explicit IP (with no port)
"""
self.agent = self._make_agent()
# there will be a getaddrinfo on the IP
self.reactor.lookups["1.2.3.4"] = "1.2.3.4"
@ -320,6 +531,7 @@ class MatrixFederationAgentTests(unittest.TestCase):
Test the behaviour when the server name contains an explicit IPv6 address
(with no port)
"""
self.agent = self._make_agent()
# there will be a getaddrinfo on the IP
self.reactor.lookups["::1"] = "::1"
@ -355,6 +567,7 @@ class MatrixFederationAgentTests(unittest.TestCase):
Test the behaviour when the server name contains an explicit IPv6 address
(with explicit port)
"""
self.agent = self._make_agent()
# there will be a getaddrinfo on the IP
self.reactor.lookups["::1"] = "::1"
@ -389,6 +602,8 @@ class MatrixFederationAgentTests(unittest.TestCase):
"""
Test the behaviour when the certificate on the server doesn't match the hostname
"""
self.agent = self._make_agent()
self.mock_resolver.resolve_service.side_effect = generate_resolve_service([])
self.reactor.lookups["testserv1"] = "1.2.3.4"
@ -441,6 +656,8 @@ class MatrixFederationAgentTests(unittest.TestCase):
Test the behaviour when the server name contains an explicit IP, but
the server cert doesn't cover it
"""
self.agent = self._make_agent()
# there will be a getaddrinfo on the IP
self.reactor.lookups["1.2.3.5"] = "1.2.3.5"
@ -471,6 +688,7 @@ class MatrixFederationAgentTests(unittest.TestCase):
"""
Test the behaviour when the server name has no port, no SRV, and no well-known
"""
self.agent = self._make_agent()
self.mock_resolver.resolve_service.side_effect = generate_resolve_service([])
self.reactor.lookups["testserv"] = "1.2.3.4"
@ -524,6 +742,7 @@ class MatrixFederationAgentTests(unittest.TestCase):
def test_get_well_known(self):
"""Test the behaviour when the .well-known delegates elsewhere"""
self.agent = self._make_agent()
self.mock_resolver.resolve_service.side_effect = generate_resolve_service([])
self.reactor.lookups["testserv"] = "1.2.3.4"
@ -587,6 +806,8 @@ class MatrixFederationAgentTests(unittest.TestCase):
"""Test the behaviour when the server name has no port and no SRV record, but
the .well-known has a 300 redirect
"""
self.agent = self._make_agent()
self.mock_resolver.resolve_service.side_effect = generate_resolve_service([])
self.reactor.lookups["testserv"] = "1.2.3.4"
self.reactor.lookups["target-server"] = "1::f"
@ -675,6 +896,7 @@ class MatrixFederationAgentTests(unittest.TestCase):
"""
Test the behaviour when the server name has an *invalid* well-known (and no SRV)
"""
self.agent = self._make_agent()
self.mock_resolver.resolve_service.side_effect = generate_resolve_service([])
self.reactor.lookups["testserv"] = "1.2.3.4"
@ -743,6 +965,7 @@ class MatrixFederationAgentTests(unittest.TestCase):
reactor=self.reactor,
tls_client_options_factory=tls_factory,
user_agent=b"test-agent", # This is unused since _well_known_resolver is passed below.
ip_whitelist=IPSet(),
ip_blacklist=IPSet(),
_srv_resolver=self.mock_resolver,
_well_known_resolver=WellKnownResolver(
@ -780,6 +1003,8 @@ class MatrixFederationAgentTests(unittest.TestCase):
"""
Test the behaviour when there is a single SRV record
"""
self.agent = self._make_agent()
self.mock_resolver.resolve_service.side_effect = generate_resolve_service(
[Server(host=b"srvtarget", port=8443)]
)
@ -820,6 +1045,8 @@ class MatrixFederationAgentTests(unittest.TestCase):
"""Test the behaviour when the .well-known redirects to a place where there
is a SRV.
"""
self.agent = self._make_agent()
self.reactor.lookups["testserv"] = "1.2.3.4"
self.reactor.lookups["srvtarget"] = "5.6.7.8"
@ -876,6 +1103,7 @@ class MatrixFederationAgentTests(unittest.TestCase):
def test_idna_servername(self):
"""test the behaviour when the server name has idna chars in"""
self.agent = self._make_agent()
self.mock_resolver.resolve_service.side_effect = generate_resolve_service([])
@ -937,6 +1165,7 @@ class MatrixFederationAgentTests(unittest.TestCase):
def test_idna_srv_target(self):
"""test the behaviour when the target of a SRV record has idna chars"""
self.agent = self._make_agent()
self.mock_resolver.resolve_service.side_effect = generate_resolve_service(
[Server(host=b"xn--trget-3qa.com", port=8443)] # târget.com
@ -1140,6 +1369,8 @@ class MatrixFederationAgentTests(unittest.TestCase):
def test_srv_fallbacks(self):
"""Test that other SRV results are tried if the first one fails."""
self.agent = self._make_agent()
self.mock_resolver.resolve_service.side_effect = generate_resolve_service(
[
Server(host=b"target.com", port=8443),
@ -1266,34 +1497,49 @@ def _check_logcontext(context):
raise AssertionError("Expected logcontext %s but was %s" % (context, current))
def _build_test_server(connection_creator):
"""Construct a test server
This builds an HTTP channel, wrapped with a TLSMemoryBIOProtocol
def _wrap_server_factory_for_tls(
factory: IProtocolFactory, sanlist: Iterable[bytes] = None
) -> IProtocolFactory:
"""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:
connection_creator (IOpenSSLServerConnectionCreator): thing to build
SSL connections
sanlist (list[bytes]): list of the SAN entries for the cert returned
by the server
factory: protocol factory to wrap
sanlist: list of domains the cert should be valid for
Returns:
TLSMemoryBIOProtocol
interfaces.IProtocolFactory
"""
if sanlist is None:
sanlist = [
b"DNS:testserv",
b"DNS:target-server",
b"DNS:xn--bcher-kva.com",
b"IP:1.2.3.4",
b"IP:::1",
]
connection_creator = TestServerTLSConnectionFactory(sanlist=sanlist)
return TLSMemoryBIOFactory(
connection_creator, isClient=False, wrappedFactory=factory
)
def _get_test_protocol_factory() -> IProtocolFactory:
"""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
server_tls_factory = TLSMemoryBIOFactory(
connection_creator, isClient=False, wrappedFactory=server_factory
)
return server_tls_factory.buildProtocol(None)
return server_factory
def _log_request(request):
def _log_request(request: str):
"""Implements Factory.log, which is expected by Request.finish"""
logger.info("Completed request %s", request)
logger.info(f"Completed request {request}")
@implementer(IPolicyForHTTPS)

75
tests/http/test_proxyagent.py
View file

@ -29,7 +29,8 @@ from twisted.protocols.tls import TLSMemoryBIOFactory, TLSMemoryBIOProtocol
from twisted.web.http import HTTPChannel
from synapse.http.client import BlacklistingReactorWrapper
from synapse.http.proxyagent import ProxyAgent, ProxyCredentials, parse_proxy
from synapse.http.connectproxyclient import ProxyCredentials
from synapse.http.proxyagent import ProxyAgent, parse_proxy
from tests.http import TestServerTLSConnectionFactory, get_test_https_policy
from tests.server import FakeTransport, ThreadedMemoryReactorClock
@ -392,7 +393,9 @@ class MatrixFederationAgentTests(TestCase):
"""
Tests that requests can be made through a proxy.
"""
self._do_http_request_via_proxy(ssl=False, auth_credentials=None)
self._do_http_request_via_proxy(
expect_proxy_ssl=False, expected_auth_credentials=None
)
@patch.dict(
os.environ,
@ -402,13 +405,17 @@ class MatrixFederationAgentTests(TestCase):
"""
Tests that authenticated requests can be made through a proxy.
"""
self._do_http_request_via_proxy(ssl=False, auth_credentials=b"bob:pinkponies")
self._do_http_request_via_proxy(
expect_proxy_ssl=False, expected_auth_credentials=b"bob:pinkponies"
)
@patch.dict(
os.environ, {"http_proxy": "https://proxy.com:8888", "no_proxy": "unused.com"}
)
def test_http_request_via_https_proxy(self):
self._do_http_request_via_proxy(ssl=True, auth_credentials=None)
self._do_http_request_via_proxy(
expect_proxy_ssl=True, expected_auth_credentials=None
)
@patch.dict(
os.environ,
@ -418,12 +425,16 @@ class MatrixFederationAgentTests(TestCase):
},
)
def test_http_request_via_https_proxy_with_auth(self):
self._do_http_request_via_proxy(ssl=True, auth_credentials=b"bob:pinkponies")
self._do_http_request_via_proxy(
expect_proxy_ssl=True, expected_auth_credentials=b"bob:pinkponies"
)
@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(ssl=False, auth_credentials=None)
self._do_https_request_via_proxy(
expect_proxy_ssl=False, expected_auth_credentials=None
)
@patch.dict(
os.environ,
@ -431,14 +442,18 @@ class MatrixFederationAgentTests(TestCase):
)
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(ssl=False, auth_credentials=b"bob:pinkponies")
self._do_https_request_via_proxy(
expect_proxy_ssl=False, expected_auth_credentials=b"bob:pinkponies"
)
@patch.dict(
os.environ, {"https_proxy": "https://proxy.com", "no_proxy": "unused.com"}
)
def test_https_request_via_https_proxy(self):
"""Tests that TLS-encrypted requests can be made through a proxy"""
self._do_https_request_via_proxy(ssl=True, auth_credentials=None)
self._do_https_request_via_proxy(
expect_proxy_ssl=True, expected_auth_credentials=None
)
@patch.dict(
os.environ,
@ -446,20 +461,22 @@ class MatrixFederationAgentTests(TestCase):
)
def test_https_request_via_https_proxy_with_auth(self):
"""Tests that authenticated, TLS-encrypted requests can be made through a proxy"""
self._do_https_request_via_proxy(ssl=True, auth_credentials=b"bob:pinkponies")
self._do_https_request_via_proxy(
expect_proxy_ssl=True, expected_auth_credentials=b"bob:pinkponies"
)
def _do_http_request_via_proxy(
self,
ssl: bool = False,
auth_credentials: Optional[bytes] = None,
expect_proxy_ssl: bool = False,
expected_auth_credentials: Optional[bytes] = None,
):
"""Send a http request via an agent and check that it is correctly received at
the proxy. The proxy can use either http or https.
Args:
ssl: True if we expect the request to connect via https to proxy
auth_credentials: credentials to authenticate at proxy
expect_proxy_ssl: True if we expect the request to connect via https to proxy
expected_auth_credentials: credentials to authenticate at proxy
"""
if ssl:
if expect_proxy_ssl:
agent = ProxyAgent(
self.reactor, use_proxy=True, contextFactory=get_test_https_policy()
)
@ -480,9 +497,9 @@ class MatrixFederationAgentTests(TestCase):
http_server = self._make_connection(
client_factory,
_get_test_protocol_factory(),
ssl=ssl,
tls_sanlist=[b"DNS:proxy.com"] if ssl else None,
expected_sni=b"proxy.com" if ssl else None,
ssl=expect_proxy_ssl,
tls_sanlist=[b"DNS:proxy.com"] if expect_proxy_ssl else None,
expected_sni=b"proxy.com" if expect_proxy_ssl else None,
)
# the FakeTransport is async, so we need to pump the reactor
@ -498,9 +515,9 @@ class MatrixFederationAgentTests(TestCase):
b"Proxy-Authorization"
)
if auth_credentials is not None:
if expected_auth_credentials is not None:
# Compute the correct header value for Proxy-Authorization
encoded_credentials = base64.b64encode(auth_credentials)
encoded_credentials = base64.b64encode(expected_auth_credentials)
expected_header_value = b"Basic " + encoded_credentials
# Validate the header's value
@ -523,14 +540,14 @@ class MatrixFederationAgentTests(TestCase):
def _do_https_request_via_proxy(
self,
ssl: bool = False,
auth_credentials: Optional[bytes] = None,
expect_proxy_ssl: bool = False,
expected_auth_credentials: Optional[bytes] = None,
):
"""Send a https request via an agent and check that it is correctly received at
the proxy and client. The proxy can use either http or https.
Args:
ssl: True if we expect the request to connect via https to proxy
auth_credentials: credentials to authenticate at proxy
expect_proxy_ssl: True if we expect the request to connect via https to proxy
expected_auth_credentials: credentials to authenticate at proxy
"""
agent = ProxyAgent(
self.reactor,
@ -552,9 +569,9 @@ class MatrixFederationAgentTests(TestCase):
proxy_server = self._make_connection(
client_factory,
_get_test_protocol_factory(),
ssl=ssl,
tls_sanlist=[b"DNS:proxy.com"] if ssl else None,
expected_sni=b"proxy.com" if ssl else None,
ssl=expect_proxy_ssl,
tls_sanlist=[b"DNS:proxy.com"] if expect_proxy_ssl else None,
expected_sni=b"proxy.com" if expect_proxy_ssl else None,
)
assert isinstance(proxy_server, HTTPChannel)
@ -570,9 +587,9 @@ class MatrixFederationAgentTests(TestCase):
b"Proxy-Authorization"
)
if auth_credentials is not None:
if expected_auth_credentials is not None:
# Compute the correct header value for Proxy-Authorization
encoded_credentials = base64.b64encode(auth_credentials)
encoded_credentials = base64.b64encode(expected_auth_credentials)
expected_header_value = b"Basic " + encoded_credentials
# Validate the header's value
@ -606,7 +623,7 @@ class MatrixFederationAgentTests(TestCase):
# Protocol to implement the proxy, which starts out by forwarding to an
# HTTPChannel (to implement the CONNECT command) and can then be switched
# into a mode where it forwards its traffic to another Protocol.)
if ssl:
if expect_proxy_ssl:
assert isinstance(proxy_server_transport, TLSMemoryBIOProtocol)
proxy_server_transport.wrappedProtocol = server_ssl_protocol
else: