Split synapse.federation.transport.server into multiple files. (#10590)

synapse/federation/transport/server/federation.py

@@ -0,0 +1,692 @@
+#  Copyright 2021 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 logging
+from typing import Dict, List, Mapping, Optional, Sequence, Tuple, Type, Union
+
+from typing_extensions import Literal
+
+import synapse
+from synapse.api.errors import Codes, SynapseError
+from synapse.api.room_versions import RoomVersions
+from synapse.api.urls import FEDERATION_UNSTABLE_PREFIX, FEDERATION_V2_PREFIX
+from synapse.federation.transport.server._base import (
+    Authenticator,
+    BaseFederationServlet,
+)
+from synapse.http.servlet import (
+    parse_boolean_from_args,
+    parse_integer_from_args,
+    parse_string_from_args,
+    parse_strings_from_args,
+)
+from synapse.server import HomeServer
+from synapse.types import JsonDict
+from synapse.util.ratelimitutils import FederationRateLimiter
+from synapse.util.versionstring import get_version_string
+
+logger = logging.getLogger(__name__)
+
+
+class BaseFederationServerServlet(BaseFederationServlet):
+    """Abstract base class for federation servlet classes which provides a federation server handler.
+
+    See BaseFederationServlet for more information.
+    """
+
+    def __init__(
+        self,
+        hs: HomeServer,
+        authenticator: Authenticator,
+        ratelimiter: FederationRateLimiter,
+        server_name: str,
+    ):
+        super().__init__(hs, authenticator, ratelimiter, server_name)
+        self.handler = hs.get_federation_server()
+
+
+class FederationSendServlet(BaseFederationServerServlet):
+    PATH = "/send/(?P<transaction_id>[^/]*)/?"
+
+    # We ratelimit manually in the handler as we queue up the requests and we
+    # don't want to fill up the ratelimiter with blocked requests.
+    RATELIMIT = False
+
+    # This is when someone is trying to send us a bunch of data.
+    async def on_PUT(
+        self,
+        origin: str,
+        content: JsonDict,
+        query: Dict[bytes, List[bytes]],
+        transaction_id: str,
+    ) -> Tuple[int, JsonDict]:
+        """Called on PUT /send/<transaction_id>/
+
+        Args:
+            transaction_id: The transaction_id associated with this request. This
+                is *not* None.
+
+        Returns:
+            Tuple of `(code, response)`, where
+            `response` is a python dict to be converted into JSON that is
+            used as the response body.
+        """
+        # Parse the request
+        try:
+            transaction_data = content
+
+            logger.debug("Decoded %s: %s", transaction_id, str(transaction_data))
+
+            logger.info(
+                "Received txn %s from %s. (PDUs: %d, EDUs: %d)",
+                transaction_id,
+                origin,
+                len(transaction_data.get("pdus", [])),
+                len(transaction_data.get("edus", [])),
+            )
+
+        except Exception as e:
+            logger.exception(e)
+            return 400, {"error": "Invalid transaction"}
+
+        code, response = await self.handler.on_incoming_transaction(
+            origin, transaction_id, self.server_name, transaction_data
+        )
+
+        return code, response
+
+
+class FederationEventServlet(BaseFederationServerServlet):
+    PATH = "/event/(?P<event_id>[^/]*)/?"
+
+    # This is when someone asks for a data item for a given server data_id pair.
+    async def on_GET(
+        self,
+        origin: str,
+        content: Literal[None],
+        query: Dict[bytes, List[bytes]],
+        event_id: str,
+    ) -> Tuple[int, Union[JsonDict, str]]:
+        return await self.handler.on_pdu_request(origin, event_id)
+
+
+class FederationStateV1Servlet(BaseFederationServerServlet):
+    PATH = "/state/(?P<room_id>[^/]*)/?"
+
+    # This is when someone asks for all data for a given room.
+    async def on_GET(
+        self,
+        origin: str,
+        content: Literal[None],
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+    ) -> Tuple[int, JsonDict]:
+        return await self.handler.on_room_state_request(
+            origin,
+            room_id,
+            parse_string_from_args(query, "event_id", None, required=False),
+        )
+
+
+class FederationStateIdsServlet(BaseFederationServerServlet):
+    PATH = "/state_ids/(?P<room_id>[^/]*)/?"
+
+    async def on_GET(
+        self,
+        origin: str,
+        content: Literal[None],
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+    ) -> Tuple[int, JsonDict]:
+        return await self.handler.on_state_ids_request(
+            origin,
+            room_id,
+            parse_string_from_args(query, "event_id", None, required=True),
+        )
+
+
+class FederationBackfillServlet(BaseFederationServerServlet):
+    PATH = "/backfill/(?P<room_id>[^/]*)/?"
+
+    async def on_GET(
+        self,
+        origin: str,
+        content: Literal[None],
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+    ) -> Tuple[int, JsonDict]:
+        versions = [x.decode("ascii") for x in query[b"v"]]
+        limit = parse_integer_from_args(query, "limit", None)
+
+        if not limit:
+            return 400, {"error": "Did not include limit param"}
+
+        return await self.handler.on_backfill_request(origin, room_id, versions, limit)
+
+
+class FederationQueryServlet(BaseFederationServerServlet):
+    PATH = "/query/(?P<query_type>[^/]*)"
+
+    # This is when we receive a server-server Query
+    async def on_GET(
+        self,
+        origin: str,
+        content: Literal[None],
+        query: Dict[bytes, List[bytes]],
+        query_type: str,
+    ) -> Tuple[int, JsonDict]:
+        args = {k.decode("utf8"): v[0].decode("utf-8") for k, v in query.items()}
+        args["origin"] = origin
+        return await self.handler.on_query_request(query_type, args)
+
+
+class FederationMakeJoinServlet(BaseFederationServerServlet):
+    PATH = "/make_join/(?P<room_id>[^/]*)/(?P<user_id>[^/]*)"
+
+    async def on_GET(
+        self,
+        origin: str,
+        content: Literal[None],
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+        user_id: str,
+    ) -> Tuple[int, JsonDict]:
+        """
+        Args:
+            origin: The authenticated server_name of the calling server
+
+            content: (GETs don't have bodies)
+
+            query: Query params from the request.
+
+            **kwargs: the dict mapping keys to path components as specified in
+                the path match regexp.
+
+        Returns:
+            Tuple of (response code, response object)
+        """
+        supported_versions = parse_strings_from_args(query, "ver", encoding="utf-8")
+        if supported_versions is None:
+            supported_versions = ["1"]
+
+        result = await self.handler.on_make_join_request(
+            origin, room_id, user_id, supported_versions=supported_versions
+        )
+        return 200, result
+
+
+class FederationMakeLeaveServlet(BaseFederationServerServlet):
+    PATH = "/make_leave/(?P<room_id>[^/]*)/(?P<user_id>[^/]*)"
+
+    async def on_GET(
+        self,
+        origin: str,
+        content: Literal[None],
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+        user_id: str,
+    ) -> Tuple[int, JsonDict]:
+        result = await self.handler.on_make_leave_request(origin, room_id, user_id)
+        return 200, result
+
+
+class FederationV1SendLeaveServlet(BaseFederationServerServlet):
+    PATH = "/send_leave/(?P<room_id>[^/]*)/(?P<event_id>[^/]*)"
+
+    async def on_PUT(
+        self,
+        origin: str,
+        content: JsonDict,
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+        event_id: str,
+    ) -> Tuple[int, Tuple[int, JsonDict]]:
+        result = await self.handler.on_send_leave_request(origin, content, room_id)
+        return 200, (200, result)
+
+
+class FederationV2SendLeaveServlet(BaseFederationServerServlet):
+    PATH = "/send_leave/(?P<room_id>[^/]*)/(?P<event_id>[^/]*)"
+
+    PREFIX = FEDERATION_V2_PREFIX
+
+    async def on_PUT(
+        self,
+        origin: str,
+        content: JsonDict,
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+        event_id: str,
+    ) -> Tuple[int, JsonDict]:
+        result = await self.handler.on_send_leave_request(origin, content, room_id)
+        return 200, result
+
+
+class FederationMakeKnockServlet(BaseFederationServerServlet):
+    PATH = "/make_knock/(?P<room_id>[^/]*)/(?P<user_id>[^/]*)"
+
+    async def on_GET(
+        self,
+        origin: str,
+        content: Literal[None],
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+        user_id: str,
+    ) -> Tuple[int, JsonDict]:
+        # Retrieve the room versions the remote homeserver claims to support
+        supported_versions = parse_strings_from_args(
+            query, "ver", required=True, encoding="utf-8"
+        )
+
+        result = await self.handler.on_make_knock_request(
+            origin, room_id, user_id, supported_versions=supported_versions
+        )
+        return 200, result
+
+
+class FederationV1SendKnockServlet(BaseFederationServerServlet):
+    PATH = "/send_knock/(?P<room_id>[^/]*)/(?P<event_id>[^/]*)"
+
+    async def on_PUT(
+        self,
+        origin: str,
+        content: JsonDict,
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+        event_id: str,
+    ) -> Tuple[int, JsonDict]:
+        result = await self.handler.on_send_knock_request(origin, content, room_id)
+        return 200, result
+
+
+class FederationEventAuthServlet(BaseFederationServerServlet):
+    PATH = "/event_auth/(?P<room_id>[^/]*)/(?P<event_id>[^/]*)"
+
+    async def on_GET(
+        self,
+        origin: str,
+        content: Literal[None],
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+        event_id: str,
+    ) -> Tuple[int, JsonDict]:
+        return await self.handler.on_event_auth(origin, room_id, event_id)
+
+
+class FederationV1SendJoinServlet(BaseFederationServerServlet):
+    PATH = "/send_join/(?P<room_id>[^/]*)/(?P<event_id>[^/]*)"
+
+    async def on_PUT(
+        self,
+        origin: str,
+        content: JsonDict,
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+        event_id: str,
+    ) -> Tuple[int, Tuple[int, JsonDict]]:
+        # TODO(paul): assert that event_id parsed from path actually
+        #   match those given in content
+        result = await self.handler.on_send_join_request(origin, content, room_id)
+        return 200, (200, result)
+
+
+class FederationV2SendJoinServlet(BaseFederationServerServlet):
+    PATH = "/send_join/(?P<room_id>[^/]*)/(?P<event_id>[^/]*)"
+
+    PREFIX = FEDERATION_V2_PREFIX
+
+    async def on_PUT(
+        self,
+        origin: str,
+        content: JsonDict,
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+        event_id: str,
+    ) -> Tuple[int, JsonDict]:
+        # TODO(paul): assert that event_id parsed from path actually
+        #   match those given in content
+        result = await self.handler.on_send_join_request(origin, content, room_id)
+        return 200, result
+
+
+class FederationV1InviteServlet(BaseFederationServerServlet):
+    PATH = "/invite/(?P<room_id>[^/]*)/(?P<event_id>[^/]*)"
+
+    async def on_PUT(
+        self,
+        origin: str,
+        content: JsonDict,
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+        event_id: str,
+    ) -> Tuple[int, Tuple[int, JsonDict]]:
+        # We don't get a room version, so we have to assume its EITHER v1 or
+        # v2. This is "fine" as the only difference between V1 and V2 is the
+        # state resolution algorithm, and we don't use that for processing
+        # invites
+        result = await self.handler.on_invite_request(
+            origin, content, room_version_id=RoomVersions.V1.identifier
+        )
+
+        # V1 federation API is defined to return a content of `[200, {...}]`
+        # due to a historical bug.
+        return 200, (200, result)
+
+
+class FederationV2InviteServlet(BaseFederationServerServlet):
+    PATH = "/invite/(?P<room_id>[^/]*)/(?P<event_id>[^/]*)"
+
+    PREFIX = FEDERATION_V2_PREFIX
+
+    async def on_PUT(
+        self,
+        origin: str,
+        content: JsonDict,
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+        event_id: str,
+    ) -> Tuple[int, JsonDict]:
+        # TODO(paul): assert that room_id/event_id parsed from path actually
+        #   match those given in content
+
+        room_version = content["room_version"]
+        event = content["event"]
+        invite_room_state = content["invite_room_state"]
+
+        # Synapse expects invite_room_state to be in unsigned, as it is in v1
+        # API
+
+        event.setdefault("unsigned", {})["invite_room_state"] = invite_room_state
+
+        result = await self.handler.on_invite_request(
+            origin, event, room_version_id=room_version
+        )
+        return 200, result
+
+
+class FederationThirdPartyInviteExchangeServlet(BaseFederationServerServlet):
+    PATH = "/exchange_third_party_invite/(?P<room_id>[^/]*)"
+
+    async def on_PUT(
+        self,
+        origin: str,
+        content: JsonDict,
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+    ) -> Tuple[int, JsonDict]:
+        await self.handler.on_exchange_third_party_invite_request(content)
+        return 200, {}
+
+
+class FederationClientKeysQueryServlet(BaseFederationServerServlet):
+    PATH = "/user/keys/query"
+
+    async def on_POST(
+        self, origin: str, content: JsonDict, query: Dict[bytes, List[bytes]]
+    ) -> Tuple[int, JsonDict]:
+        return await self.handler.on_query_client_keys(origin, content)
+
+
+class FederationUserDevicesQueryServlet(BaseFederationServerServlet):
+    PATH = "/user/devices/(?P<user_id>[^/]*)"
+
+    async def on_GET(
+        self,
+        origin: str,
+        content: Literal[None],
+        query: Dict[bytes, List[bytes]],
+        user_id: str,
+    ) -> Tuple[int, JsonDict]:
+        return await self.handler.on_query_user_devices(origin, user_id)
+
+
+class FederationClientKeysClaimServlet(BaseFederationServerServlet):
+    PATH = "/user/keys/claim"
+
+    async def on_POST(
+        self, origin: str, content: JsonDict, query: Dict[bytes, List[bytes]]
+    ) -> Tuple[int, JsonDict]:
+        response = await self.handler.on_claim_client_keys(origin, content)
+        return 200, response
+
+
+class FederationGetMissingEventsServlet(BaseFederationServerServlet):
+    # TODO(paul): Why does this path alone end with "/?" optional?
+    PATH = "/get_missing_events/(?P<room_id>[^/]*)/?"
+
+    async def on_POST(
+        self,
+        origin: str,
+        content: JsonDict,
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+    ) -> Tuple[int, JsonDict]:
+        limit = int(content.get("limit", 10))
+        earliest_events = content.get("earliest_events", [])
+        latest_events = content.get("latest_events", [])
+
+        result = await self.handler.on_get_missing_events(
+            origin,
+            room_id=room_id,
+            earliest_events=earliest_events,
+            latest_events=latest_events,
+            limit=limit,
+        )
+
+        return 200, result
+
+
+class On3pidBindServlet(BaseFederationServerServlet):
+    PATH = "/3pid/onbind"
+
+    REQUIRE_AUTH = False
+
+    async def on_POST(
+        self, origin: Optional[str], content: JsonDict, query: Dict[bytes, List[bytes]]
+    ) -> Tuple[int, JsonDict]:
+        if "invites" in content:
+            last_exception = None
+            for invite in content["invites"]:
+                try:
+                    if "signed" not in invite or "token" not in invite["signed"]:
+                        message = (
+                            "Rejecting received notification of third-"
+                            "party invite without signed: %s" % (invite,)
+                        )
+                        logger.info(message)
+                        raise SynapseError(400, message)
+                    await self.handler.exchange_third_party_invite(
+                        invite["sender"],
+                        invite["mxid"],
+                        invite["room_id"],
+                        invite["signed"],
+                    )
+                except Exception as e:
+                    last_exception = e
+            if last_exception:
+                raise last_exception
+        return 200, {}
+
+
+class FederationVersionServlet(BaseFederationServlet):
+    PATH = "/version"
+
+    REQUIRE_AUTH = False
+
+    async def on_GET(
+        self,
+        origin: Optional[str],
+        content: Literal[None],
+        query: Dict[bytes, List[bytes]],
+    ) -> Tuple[int, JsonDict]:
+        return (
+            200,
+            {"server": {"name": "Synapse", "version": get_version_string(synapse)}},
+        )
+
+
+class FederationSpaceSummaryServlet(BaseFederationServlet):
+    PREFIX = FEDERATION_UNSTABLE_PREFIX + "/org.matrix.msc2946"
+    PATH = "/spaces/(?P<room_id>[^/]*)"
+
+    def __init__(
+        self,
+        hs: HomeServer,
+        authenticator: Authenticator,
+        ratelimiter: FederationRateLimiter,
+        server_name: str,
+    ):
+        super().__init__(hs, authenticator, ratelimiter, server_name)
+        self.handler = hs.get_space_summary_handler()
+
+    async def on_GET(
+        self,
+        origin: str,
+        content: Literal[None],
+        query: Mapping[bytes, Sequence[bytes]],
+        room_id: str,
+    ) -> Tuple[int, JsonDict]:
+        suggested_only = parse_boolean_from_args(query, "suggested_only", default=False)
+        max_rooms_per_space = parse_integer_from_args(query, "max_rooms_per_space")
+
+        exclude_rooms = parse_strings_from_args(query, "exclude_rooms", default=[])
+
+        return 200, await self.handler.federation_space_summary(
+            origin, room_id, suggested_only, max_rooms_per_space, exclude_rooms
+        )
+
+    # TODO When switching to the stable endpoint, remove the POST handler.
+    async def on_POST(
+        self,
+        origin: str,
+        content: JsonDict,
+        query: Mapping[bytes, Sequence[bytes]],
+        room_id: str,
+    ) -> Tuple[int, JsonDict]:
+        suggested_only = content.get("suggested_only", False)
+        if not isinstance(suggested_only, bool):
+            raise SynapseError(
+                400, "'suggested_only' must be a boolean", Codes.BAD_JSON
+            )
+
+        exclude_rooms = content.get("exclude_rooms", [])
+        if not isinstance(exclude_rooms, list) or any(
+            not isinstance(x, str) for x in exclude_rooms
+        ):
+            raise SynapseError(400, "bad value for 'exclude_rooms'", Codes.BAD_JSON)
+
+        max_rooms_per_space = content.get("max_rooms_per_space")
+        if max_rooms_per_space is not None and not isinstance(max_rooms_per_space, int):
+            raise SynapseError(
+                400, "bad value for 'max_rooms_per_space'", Codes.BAD_JSON
+            )
+
+        return 200, await self.handler.federation_space_summary(
+            origin, room_id, suggested_only, max_rooms_per_space, exclude_rooms
+        )
+
+
+class FederationRoomHierarchyServlet(BaseFederationServlet):
+    PREFIX = FEDERATION_UNSTABLE_PREFIX + "/org.matrix.msc2946"
+    PATH = "/hierarchy/(?P<room_id>[^/]*)"
+
+    def __init__(
+        self,
+        hs: HomeServer,
+        authenticator: Authenticator,
+        ratelimiter: FederationRateLimiter,
+        server_name: str,
+    ):
+        super().__init__(hs, authenticator, ratelimiter, server_name)
+        self.handler = hs.get_space_summary_handler()
+
+    async def on_GET(
+        self,
+        origin: str,
+        content: Literal[None],
+        query: Mapping[bytes, Sequence[bytes]],
+        room_id: str,
+    ) -> Tuple[int, JsonDict]:
+        suggested_only = parse_boolean_from_args(query, "suggested_only", default=False)
+        return 200, await self.handler.get_federation_hierarchy(
+            origin, room_id, suggested_only
+        )
+
+
+class RoomComplexityServlet(BaseFederationServlet):
+    """
+    Indicates to other servers how complex (and therefore likely
+    resource-intensive) a public room this server knows about is.
+    """
+
+    PATH = "/rooms/(?P<room_id>[^/]*)/complexity"
+    PREFIX = FEDERATION_UNSTABLE_PREFIX
+
+    def __init__(
+        self,
+        hs: HomeServer,
+        authenticator: Authenticator,
+        ratelimiter: FederationRateLimiter,
+        server_name: str,
+    ):
+        super().__init__(hs, authenticator, ratelimiter, server_name)
+        self._store = self.hs.get_datastore()
+
+    async def on_GET(
+        self,
+        origin: str,
+        content: Literal[None],
+        query: Dict[bytes, List[bytes]],
+        room_id: str,
+    ) -> Tuple[int, JsonDict]:
+        is_public = await self._store.is_room_world_readable_or_publicly_joinable(
+            room_id
+        )
+
+        if not is_public:
+            raise SynapseError(404, "Room not found", errcode=Codes.INVALID_PARAM)
+
+        complexity = await self._store.get_room_complexity(room_id)
+        return 200, complexity
+
+
+FEDERATION_SERVLET_CLASSES: Tuple[Type[BaseFederationServlet], ...] = (
+    FederationSendServlet,
+    FederationEventServlet,
+    FederationStateV1Servlet,
+    FederationStateIdsServlet,
+    FederationBackfillServlet,
+    FederationQueryServlet,
+    FederationMakeJoinServlet,
+    FederationMakeLeaveServlet,
+    FederationEventServlet,
+    FederationV1SendJoinServlet,
+    FederationV2SendJoinServlet,
+    FederationV1SendLeaveServlet,
+    FederationV2SendLeaveServlet,
+    FederationV1InviteServlet,
+    FederationV2InviteServlet,
+    FederationGetMissingEventsServlet,
+    FederationEventAuthServlet,
+    FederationClientKeysQueryServlet,
+    FederationUserDevicesQueryServlet,
+    FederationClientKeysClaimServlet,
+    FederationThirdPartyInviteExchangeServlet,
+    On3pidBindServlet,
+    FederationVersionServlet,
+    RoomComplexityServlet,
+    FederationSpaceSummaryServlet,
+    FederationRoomHierarchyServlet,
+    FederationV1SendKnockServlet,
+    FederationMakeKnockServlet,
+)