diff options
Diffstat (limited to 'synapse/http/federation')
| -rw-r--r-- | synapse/http/federation/matrix_federation_agent.py | 100 |
1 files changed, 87 insertions, 13 deletions
diff --git a/synapse/http/federation/matrix_federation_agent.py b/synapse/http/federation/matrix_federation_agent.py index c16b7f10e6..1238bfd287 100644 --- a/synapse/http/federation/matrix_federation_agent.py +++ b/synapse/http/federation/matrix_federation_agent.py @@ -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( |