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Diffstat (limited to 'synapse/http/proxy.py')
| -rw-r--r-- | synapse/http/proxy.py | 249 |
1 files changed, 0 insertions, 249 deletions
diff --git a/synapse/http/proxy.py b/synapse/http/proxy.py deleted file mode 100644 index 0874d67760..0000000000 --- a/synapse/http/proxy.py +++ /dev/null @@ -1,249 +0,0 @@ -# Copyright 2023 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 json -import logging -import urllib.parse -from typing import TYPE_CHECKING, Any, Optional, Set, Tuple, cast - -from twisted.internet import protocol -from twisted.internet.interfaces import ITCPTransport -from twisted.internet.protocol import connectionDone -from twisted.python import failure -from twisted.python.failure import Failure -from twisted.web.client import ResponseDone -from twisted.web.http_headers import Headers -from twisted.web.iweb import IAgent, IResponse -from twisted.web.resource import IResource -from twisted.web.server import Site - -from synapse.api.errors import Codes -from synapse.http import QuieterFileBodyProducer -from synapse.http.server import _AsyncResource -from synapse.logging.context import make_deferred_yieldable, run_in_background -from synapse.types import ISynapseReactor -from synapse.util.async_helpers import timeout_deferred - -if TYPE_CHECKING: - from synapse.http.site import SynapseRequest - -logger = logging.getLogger(__name__) - -# "Hop-by-hop" headers (as opposed to "end-to-end" headers) as defined by RFC2616 -# section 13.5.1 and referenced in RFC9110 section 7.6.1. These are meant to only be -# consumed by the immediate recipient and not be forwarded on. -HOP_BY_HOP_HEADERS = { - "Connection", - "Keep-Alive", - "Proxy-Authenticate", - "Proxy-Authorization", - "TE", - "Trailers", - "Transfer-Encoding", - "Upgrade", -} - - -def parse_connection_header_value( - connection_header_value: Optional[bytes], -) -> Set[str]: - """ - Parse the `Connection` header to determine which headers we should not be copied - over from the remote response. - - As defined by RFC2616 section 14.10 and RFC9110 section 7.6.1 - - Example: `Connection: close, X-Foo, X-Bar` will return `{"Close", "X-Foo", "X-Bar"}` - - Even though "close" is a special directive, let's just treat it as just another - header for simplicity. If people want to check for this directive, they can simply - check for `"Close" in headers`. - - Args: - connection_header_value: The value of the `Connection` header. - - Returns: - The set of header names that should not be copied over from the remote response. - The keys are capitalized in canonical capitalization. - """ - headers = Headers() - extra_headers_to_remove: Set[str] = set() - if connection_header_value: - extra_headers_to_remove = { - headers._canonicalNameCaps(connection_option.strip()).decode("ascii") - for connection_option in connection_header_value.split(b",") - } - - return extra_headers_to_remove - - -class ProxyResource(_AsyncResource): - """ - A stub resource that proxies any requests with a `matrix-federation://` scheme - through the given `federation_agent` to the remote homeserver and ferries back the - info. - """ - - isLeaf = True - - def __init__(self, reactor: ISynapseReactor, federation_agent: IAgent): - super().__init__(True) - - self.reactor = reactor - self.agent = federation_agent - - async def _async_render(self, request: "SynapseRequest") -> Tuple[int, Any]: - uri = urllib.parse.urlparse(request.uri) - assert uri.scheme == b"matrix-federation" - - headers = Headers() - for header_name in (b"User-Agent", b"Authorization", b"Content-Type"): - header_value = request.getHeader(header_name) - if header_value: - headers.addRawHeader(header_name, header_value) - - request_deferred = run_in_background( - self.agent.request, - request.method, - request.uri, - headers=headers, - bodyProducer=QuieterFileBodyProducer(request.content), - ) - request_deferred = timeout_deferred( - request_deferred, - # This should be set longer than the timeout in `MatrixFederationHttpClient` - # so that it has enough time to complete and pass us the data before we give - # up. - timeout=90, - reactor=self.reactor, - ) - - response = await make_deferred_yieldable(request_deferred) - - return response.code, response - - def _send_response( - self, - request: "SynapseRequest", - code: int, - response_object: Any, - ) -> None: - response = cast(IResponse, response_object) - response_headers = cast(Headers, response.headers) - - request.setResponseCode(code) - - # The `Connection` header also defines which headers should not be copied over. - connection_header = response_headers.getRawHeaders(b"connection") - extra_headers_to_remove = parse_connection_header_value( - connection_header[0] if connection_header else None - ) - - # Copy headers. - for k, v in response_headers.getAllRawHeaders(): - # Do not copy over any hop-by-hop headers. These are meant to only be - # consumed by the immediate recipient and not be forwarded on. - header_key = k.decode("ascii") - if ( - header_key in HOP_BY_HOP_HEADERS - or header_key in extra_headers_to_remove - ): - continue - - request.responseHeaders.setRawHeaders(k, v) - - response.deliverBody(_ProxyResponseBody(request)) - - def _send_error_response( - self, - f: failure.Failure, - request: "SynapseRequest", - ) -> None: - request.setResponseCode(502) - request.setHeader(b"Content-Type", b"application/json") - request.write( - ( - json.dumps( - { - "errcode": Codes.UNKNOWN, - "err": "ProxyResource: Error when proxying request: %s %s -> %s" - % ( - request.method.decode("ascii"), - request.uri.decode("ascii"), - f, - ), - } - ) - ).encode() - ) - request.finish() - - -class _ProxyResponseBody(protocol.Protocol): - """ - A protocol that proxies the given remote response data back out to the given local - request. - """ - - transport: Optional[ITCPTransport] = None - - def __init__(self, request: "SynapseRequest") -> None: - self._request = request - - def dataReceived(self, data: bytes) -> None: - # Avoid sending response data to the local request that already disconnected - if self._request._disconnected and self.transport is not None: - # Close the connection (forcefully) since all the data will get - # discarded anyway. - self.transport.abortConnection() - return - - self._request.write(data) - - def connectionLost(self, reason: Failure = connectionDone) -> None: - # If the local request is already finished (successfully or failed), don't - # worry about sending anything back. - if self._request.finished: - return - - if reason.check(ResponseDone): - self._request.finish() - else: - # Abort the underlying request since our remote request also failed. - self._request.transport.abortConnection() - - -class ProxySite(Site): - """ - Proxies any requests with a `matrix-federation://` scheme through the given - `federation_agent`. Otherwise, behaves like a normal `Site`. - """ - - def __init__( - self, - resource: IResource, - reactor: ISynapseReactor, - federation_agent: IAgent, - ): - super().__init__(resource, reactor=reactor) - - self._proxy_resource = ProxyResource(reactor, federation_agent) - - def getResourceFor(self, request: "SynapseRequest") -> IResource: - uri = urllib.parse.urlparse(request.uri) - if uri.scheme == b"matrix-federation": - return self._proxy_resource - - return super().getResourceFor(request) |