diff options
Diffstat (limited to 'synapse/http/matrixfederationclient.py')
| -rw-r--r-- | synapse/http/matrixfederationclient.py | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/synapse/http/matrixfederationclient.py b/synapse/http/matrixfederationclient.py index 104b803b0f..749b01dd0e 100644 --- a/synapse/http/matrixfederationclient.py +++ b/synapse/http/matrixfederationclient.py @@ -75,9 +75,11 @@ from synapse.http.client import ( BlocklistingAgentWrapper, BodyExceededMaxSize, ByteWriteable, + SimpleHttpClient, _make_scheduler, encode_query_args, read_body_with_max_size, + read_multipart_response, ) from synapse.http.connectproxyclient import BearerProxyCredentials from synapse.http.federation.matrix_federation_agent import MatrixFederationAgent @@ -466,6 +468,13 @@ class MatrixFederationHttpClient: self._sleeper = AwakenableSleeper(self.reactor) + self._simple_http_client = SimpleHttpClient( + hs, + ip_blocklist=hs.config.server.federation_ip_range_blocklist, + ip_allowlist=hs.config.server.federation_ip_range_allowlist, + use_proxy=True, + ) + def wake_destination(self, destination: str) -> None: """Called when the remote server may have come back online.""" @@ -1553,6 +1562,189 @@ class MatrixFederationHttpClient: ) return length, headers + async def federation_get_file( + self, + destination: str, + path: str, + output_stream: BinaryIO, + download_ratelimiter: Ratelimiter, + ip_address: str, + max_size: int, + args: Optional[QueryParams] = None, + retry_on_dns_fail: bool = True, + ignore_backoff: bool = False, + ) -> Tuple[int, Dict[bytes, List[bytes]], bytes]: + """GETs a file from a given homeserver over the federation /download endpoint + Args: + destination: The remote server to send the HTTP request to. + path: The HTTP path to GET. + output_stream: File to write the response body to. + download_ratelimiter: a ratelimiter to limit remote media downloads, keyed to + requester IP + ip_address: IP address of the requester + max_size: maximum allowable size in bytes of the file + args: Optional dictionary used to create the query string. + ignore_backoff: true to ignore the historical backoff data + and try the request anyway. + + Returns: + Resolves to an (int, dict, bytes) tuple of + the file length, a dict of the response headers, and the file json + + Raises: + HttpResponseException: If we get an HTTP response code >= 300 + (except 429). + NotRetryingDestination: If we are not yet ready to retry this + server. + FederationDeniedError: If this destination is not on our + federation whitelist + RequestSendFailed: If there were problems connecting to the + remote, due to e.g. DNS failures, connection timeouts etc. + SynapseError: If the requested file exceeds ratelimits or the response from the + remote server is not a multipart response + AssertionError: if the resolved multipart response's length is None + """ + request = MatrixFederationRequest( + method="GET", destination=destination, path=path, query=args + ) + + # check for a minimum balance of 1MiB in ratelimiter before initiating request + send_req, _ = await download_ratelimiter.can_do_action( + requester=None, key=ip_address, n_actions=1048576, update=False + ) + + if not send_req: + msg = "Requested file size exceeds ratelimits" + logger.warning( + "{%s} [%s] %s", + request.txn_id, + request.destination, + msg, + ) + raise SynapseError(HTTPStatus.TOO_MANY_REQUESTS, msg, Codes.LIMIT_EXCEEDED) + + response = await self._send_request( + request, + retry_on_dns_fail=retry_on_dns_fail, + ignore_backoff=ignore_backoff, + ) + + headers = dict(response.headers.getAllRawHeaders()) + + expected_size = response.length + # if we don't get an expected length then use the max length + if expected_size == UNKNOWN_LENGTH: + expected_size = max_size + logger.debug( + f"File size unknown, assuming file is max allowable size: {max_size}" + ) + + read_body, _ = await download_ratelimiter.can_do_action( + requester=None, + key=ip_address, + n_actions=expected_size, + ) + if not read_body: + msg = "Requested file size exceeds ratelimits" + logger.warning( + "{%s} [%s] %s", + request.txn_id, + request.destination, + msg, + ) + raise SynapseError(HTTPStatus.TOO_MANY_REQUESTS, msg, Codes.LIMIT_EXCEEDED) + + # this should be a multipart/mixed response with the boundary string in the header + try: + raw_content_type = headers.get(b"Content-Type") + assert raw_content_type is not None + content_type = raw_content_type[0].decode("UTF-8") + content_type_parts = content_type.split("boundary=") + boundary = content_type_parts[1] + except Exception: + msg = "Remote response is malformed: expected Content-Type of multipart/mixed with a boundary present." + logger.warning( + "{%s} [%s] %s", + request.txn_id, + request.destination, + msg, + ) + raise SynapseError(HTTPStatus.BAD_GATEWAY, msg) + + try: + # add a byte of headroom to max size as `_MultipartParserProtocol.dataReceived` errs at >= + deferred = read_multipart_response( + response, output_stream, boundary, expected_size + 1 + ) + deferred.addTimeout(self.default_timeout_seconds, self.reactor) + except BodyExceededMaxSize: + msg = "Requested file is too large > %r bytes" % (expected_size,) + logger.warning( + "{%s} [%s] %s", + request.txn_id, + request.destination, + msg, + ) + raise SynapseError(HTTPStatus.BAD_GATEWAY, msg, Codes.TOO_LARGE) + except defer.TimeoutError as e: + logger.warning( + "{%s} [%s] Timed out reading response - %s %s", + request.txn_id, + request.destination, + request.method, + request.uri.decode("ascii"), + ) + raise RequestSendFailed(e, can_retry=True) from e + except ResponseFailed as e: + logger.warning( + "{%s} [%s] Failed to read response - %s %s", + request.txn_id, + request.destination, + request.method, + request.uri.decode("ascii"), + ) + raise RequestSendFailed(e, can_retry=True) from e + except Exception as e: + logger.warning( + "{%s} [%s] Error reading response: %s", + request.txn_id, + request.destination, + e, + ) + raise + + multipart_response = await make_deferred_yieldable(deferred) + if not multipart_response.url: + assert multipart_response.length is not None + length = multipart_response.length + headers[b"Content-Type"] = [multipart_response.content_type] + headers[b"Content-Disposition"] = [multipart_response.disposition] + + # the response contained a redirect url to download the file from + else: + str_url = multipart_response.url.decode("utf-8") + logger.info( + "{%s} [%s] File download redirected, now downloading from: %s", + request.txn_id, + request.destination, + str_url, + ) + length, headers, _, _ = await self._simple_http_client.get_file( + str_url, output_stream, expected_size + ) + + logger.info( + "{%s} [%s] Completed: %d %s [%d bytes] %s %s", + request.txn_id, + request.destination, + response.code, + response.phrase.decode("ascii", errors="replace"), + length, + request.method, + request.uri.decode("ascii"), + ) + return length, headers, multipart_response.json + def _flatten_response_never_received(e: BaseException) -> str: if hasattr(e, "reasons"): |