dendrite/clientapi/routing/sendevent.go
2022-11-14 12:30:20 +00:00

341 lines
11 KiB
Go

// Copyright 2017 Vector Creations Ltd
//
// 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.
package routing
import (
"context"
"encoding/json"
"fmt"
"net/http"
"reflect"
"sync"
"time"
"github.com/matrix-org/gomatrixserverlib"
"github.com/matrix-org/util"
"github.com/prometheus/client_golang/prometheus"
"github.com/sirupsen/logrus"
"github.com/matrix-org/dendrite/clientapi/httputil"
"github.com/matrix-org/dendrite/clientapi/jsonerror"
"github.com/matrix-org/dendrite/internal/eventutil"
"github.com/matrix-org/dendrite/internal/transactions"
"github.com/matrix-org/dendrite/roomserver/api"
"github.com/matrix-org/dendrite/setup/config"
userapi "github.com/matrix-org/dendrite/userapi/api"
)
// http://matrix.org/docs/spec/client_server/r0.2.0.html#put-matrix-client-r0-rooms-roomid-send-eventtype-txnid
// http://matrix.org/docs/spec/client_server/r0.2.0.html#put-matrix-client-r0-rooms-roomid-state-eventtype-statekey
type sendEventResponse struct {
EventID string `json:"event_id"`
}
var (
userRoomSendMutexes sync.Map // (roomID+userID) -> mutex. mutexes to ensure correct ordering of sendEvents
)
var sendEventDuration = prometheus.NewHistogramVec(
prometheus.HistogramOpts{
Namespace: "dendrite",
Subsystem: "clientapi",
Name: "sendevent_duration_millis",
Help: "How long it takes to build and submit a new event from the client API to the roomserver",
Buckets: []float64{ // milliseconds
5, 10, 25, 50, 75, 100, 250, 500,
1000, 2000, 3000, 4000, 5000, 6000,
7000, 8000, 9000, 10000, 15000, 20000,
},
},
[]string{"action"},
)
// SendEvent implements:
//
// /rooms/{roomID}/send/{eventType}
// /rooms/{roomID}/send/{eventType}/{txnID}
// /rooms/{roomID}/state/{eventType}/{stateKey}
func SendEvent(
req *http.Request,
device *userapi.Device,
roomID, eventType string, txnID, stateKey *string,
cfg *config.ClientAPI,
rsAPI api.ClientRoomserverAPI,
txnCache *transactions.Cache,
) util.JSONResponse {
verReq := api.QueryRoomVersionForRoomRequest{RoomID: roomID}
verRes := api.QueryRoomVersionForRoomResponse{}
if err := rsAPI.QueryRoomVersionForRoom(req.Context(), &verReq, &verRes); err != nil {
return util.JSONResponse{
Code: http.StatusBadRequest,
JSON: jsonerror.UnsupportedRoomVersion(err.Error()),
}
}
if txnID != nil {
// Try to fetch response from transactionsCache
if res, ok := txnCache.FetchTransaction(device.AccessToken, *txnID, req.URL); ok {
return *res
}
}
// create a mutex for the specific user in the specific room
// this avoids a situation where events that are received in quick succession are sent to the roomserver in a jumbled order
userID := device.UserID
domain := device.UserDomain()
mutex, _ := userRoomSendMutexes.LoadOrStore(roomID+userID, &sync.Mutex{})
mutex.(*sync.Mutex).Lock()
defer mutex.(*sync.Mutex).Unlock()
var r map[string]interface{} // must be a JSON object
resErr := httputil.UnmarshalJSONRequest(req, &r)
if resErr != nil {
return *resErr
}
if stateKey != nil {
// If the existing/new state content are equal, return the existing event_id, making the request idempotent.
if resp := stateEqual(req.Context(), rsAPI, eventType, *stateKey, roomID, r); resp != nil {
return *resp
}
}
startedGeneratingEvent := time.Now()
// If we're sending a membership update, make sure to strip the authorised
// via key if it is present, otherwise other servers won't be able to auth
// the event if the room is set to the "restricted" join rule.
if eventType == gomatrixserverlib.MRoomMember {
delete(r, "join_authorised_via_users_server")
}
evTime, err := httputil.ParseTSParam(req)
if err != nil {
return util.JSONResponse{
Code: http.StatusBadRequest,
JSON: jsonerror.InvalidArgumentValue(err.Error()),
}
}
e, resErr := generateSendEvent(req.Context(), r, device, roomID, eventType, stateKey, cfg, rsAPI, evTime)
if resErr != nil {
return *resErr
}
timeToGenerateEvent := time.Since(startedGeneratingEvent)
// validate that the aliases exists
if eventType == gomatrixserverlib.MRoomCanonicalAlias && stateKey != nil && *stateKey == "" {
aliasReq := api.AliasEvent{}
if err = json.Unmarshal(e.Content(), &aliasReq); err != nil {
return util.ErrorResponse(fmt.Errorf("unable to parse alias event: %w", err))
}
if !aliasReq.Valid() {
return util.JSONResponse{
Code: http.StatusBadRequest,
JSON: jsonerror.InvalidParam("Request contains invalid aliases."),
}
}
aliasRes := &api.GetAliasesForRoomIDResponse{}
if err = rsAPI.GetAliasesForRoomID(req.Context(), &api.GetAliasesForRoomIDRequest{RoomID: roomID}, aliasRes); err != nil {
return jsonerror.InternalServerError()
}
var found int
requestAliases := append(aliasReq.AltAliases, aliasReq.Alias)
for _, alias := range aliasRes.Aliases {
for _, altAlias := range requestAliases {
if altAlias == alias {
found++
}
}
}
// check that we found at least the same amount of existing aliases as are in the request
if aliasReq.Alias != "" && found < len(requestAliases) {
return util.JSONResponse{
Code: http.StatusBadRequest,
JSON: jsonerror.BadAlias("No matching alias found."),
}
}
}
var txnAndSessionID *api.TransactionID
if txnID != nil {
txnAndSessionID = &api.TransactionID{
TransactionID: *txnID,
SessionID: device.SessionID,
}
}
// pass the new event to the roomserver and receive the correct event ID
// event ID in case of duplicate transaction is discarded
startedSubmittingEvent := time.Now()
if err := api.SendEvents(
req.Context(), rsAPI,
api.KindNew,
[]*gomatrixserverlib.HeaderedEvent{
e.Headered(verRes.RoomVersion),
},
device.UserDomain(),
domain,
domain,
txnAndSessionID,
false,
); err != nil {
util.GetLogger(req.Context()).WithError(err).Error("SendEvents failed")
return jsonerror.InternalServerError()
}
timeToSubmitEvent := time.Since(startedSubmittingEvent)
util.GetLogger(req.Context()).WithFields(logrus.Fields{
"event_id": e.EventID(),
"room_id": roomID,
"room_version": verRes.RoomVersion,
}).Info("Sent event to roomserver")
res := util.JSONResponse{
Code: http.StatusOK,
JSON: sendEventResponse{e.EventID()},
}
// Add response to transactionsCache
if txnID != nil {
txnCache.AddTransaction(device.AccessToken, *txnID, req.URL, &res)
}
// Take a note of how long it took to generate the event vs submit
// it to the roomserver.
sendEventDuration.With(prometheus.Labels{"action": "build"}).Observe(float64(timeToGenerateEvent.Milliseconds()))
sendEventDuration.With(prometheus.Labels{"action": "submit"}).Observe(float64(timeToSubmitEvent.Milliseconds()))
return res
}
// stateEqual compares the new and the existing state event content. If they are equal, returns a *util.JSONResponse
// with the existing event_id, making this an idempotent request.
func stateEqual(ctx context.Context, rsAPI api.ClientRoomserverAPI, eventType, stateKey, roomID string, newContent map[string]interface{}) *util.JSONResponse {
stateRes := api.QueryCurrentStateResponse{}
tuple := gomatrixserverlib.StateKeyTuple{
EventType: eventType,
StateKey: stateKey,
}
err := rsAPI.QueryCurrentState(ctx, &api.QueryCurrentStateRequest{
RoomID: roomID,
StateTuples: []gomatrixserverlib.StateKeyTuple{tuple},
}, &stateRes)
if err != nil {
return nil
}
if existingEvent, ok := stateRes.StateEvents[tuple]; ok {
var existingContent map[string]interface{}
if err = json.Unmarshal(existingEvent.Content(), &existingContent); err != nil {
return nil
}
if reflect.DeepEqual(existingContent, newContent) {
return &util.JSONResponse{
Code: http.StatusOK,
JSON: sendEventResponse{existingEvent.EventID()},
}
}
}
return nil
}
func generateSendEvent(
ctx context.Context,
r map[string]interface{},
device *userapi.Device,
roomID, eventType string, stateKey *string,
cfg *config.ClientAPI,
rsAPI api.ClientRoomserverAPI,
evTime time.Time,
) (*gomatrixserverlib.Event, *util.JSONResponse) {
// parse the incoming http request
userID := device.UserID
// create the new event and set all the fields we can
builder := gomatrixserverlib.EventBuilder{
Sender: userID,
RoomID: roomID,
Type: eventType,
StateKey: stateKey,
}
err := builder.SetContent(r)
if err != nil {
util.GetLogger(ctx).WithError(err).Error("builder.SetContent failed")
resErr := jsonerror.InternalServerError()
return nil, &resErr
}
var queryRes api.QueryLatestEventsAndStateResponse
e, err := eventutil.QueryAndBuildEvent(ctx, &builder, cfg.Matrix, evTime, rsAPI, &queryRes)
if err == eventutil.ErrRoomNoExists {
return nil, &util.JSONResponse{
Code: http.StatusNotFound,
JSON: jsonerror.NotFound("Room does not exist"),
}
} else if e, ok := err.(gomatrixserverlib.BadJSONError); ok {
return nil, &util.JSONResponse{
Code: http.StatusBadRequest,
JSON: jsonerror.BadJSON(e.Error()),
}
} else if e, ok := err.(gomatrixserverlib.EventValidationError); ok {
if e.Code == gomatrixserverlib.EventValidationTooLarge {
return nil, &util.JSONResponse{
Code: http.StatusRequestEntityTooLarge,
JSON: jsonerror.BadJSON(e.Error()),
}
}
return nil, &util.JSONResponse{
Code: http.StatusBadRequest,
JSON: jsonerror.BadJSON(e.Error()),
}
} else if err != nil {
util.GetLogger(ctx).WithError(err).Error("eventutil.BuildEvent failed")
resErr := jsonerror.InternalServerError()
return nil, &resErr
}
// check to see if this user can perform this operation
stateEvents := make([]*gomatrixserverlib.Event, len(queryRes.StateEvents))
for i := range queryRes.StateEvents {
stateEvents[i] = queryRes.StateEvents[i].Event
}
provider := gomatrixserverlib.NewAuthEvents(stateEvents)
if err = gomatrixserverlib.Allowed(e.Event, &provider); err != nil {
return nil, &util.JSONResponse{
Code: http.StatusForbidden,
JSON: jsonerror.Forbidden(err.Error()), // TODO: Is this error string comprehensible to the client?
}
}
// User should not be able to send a tombstone event to the same room.
if e.Type() == "m.room.tombstone" {
content := make(map[string]interface{})
if err = json.Unmarshal(e.Content(), &content); err != nil {
util.GetLogger(ctx).WithError(err).Error("Cannot unmarshal the event content.")
return nil, &util.JSONResponse{
Code: http.StatusBadRequest,
JSON: jsonerror.BadJSON("Cannot unmarshal the event content."),
}
}
if content["replacement_room"] == e.RoomID() {
return nil, &util.JSONResponse{
Code: http.StatusBadRequest,
JSON: jsonerror.InvalidParam("Cannot send tombstone event that points to the same room."),
}
}
}
return e.Event, nil
}