Fix linter errors

clientapi/routing/createroom.go

@@ -48,6 +48,7 @@ type createRoomRequest struct {
 	RoomVersion               gomatrixserverlib.RoomVersion      `json:"room_version"`
 	PowerLevelContentOverride json.RawMessage                    `json:"power_level_content_override"`
 	IsDirect                  bool                               `json:"is_direct"`
+	CryptoID                  string                             `json:"cryptoid"`
 }
 
 func (r createRoomRequest) Validate() *util.JSONResponse {
@@ -107,12 +108,27 @@ type createRoomResponse struct {
 	RoomAlias string `json:"room_alias,omitempty"` // in synapse not spec
 }
 
+type createRoomCryptoIDsResponse struct {
+	RoomID  string            `json:"room_id"`
+	Version string            `json:"room_version"`
+	PDUs    []json.RawMessage `json:"pdus"`
+}
+
+func ToProtoEvents(ctx context.Context, events []gomatrixserverlib.PDU, rsAPI roomserverAPI.ClientRoomserverAPI) []json.RawMessage {
+	result := make([]json.RawMessage, len(events))
+	for i, event := range events {
+		result[i] = json.RawMessage(event.JSON())
+	}
+	return result
+}
+
 // CreateRoom implements /createRoom
 func CreateRoom(
 	req *http.Request, device *api.Device,
 	cfg *config.ClientAPI,
 	profileAPI api.ClientUserAPI, rsAPI roomserverAPI.ClientRoomserverAPI,
 	asAPI appserviceAPI.AppServiceInternalAPI,
+	cryptoIDs bool,
 ) util.JSONResponse {
 	var createRequest createRoomRequest
 	resErr := httputil.UnmarshalJSONRequest(req, &createRequest)
@@ -129,10 +145,9 @@ func CreateRoom(
 			JSON: spec.InvalidParam(err.Error()),
 		}
 	}
-	return createRoom(req.Context(), createRequest, device, cfg, profileAPI, rsAPI, asAPI, evTime)
+	return createRoom(req.Context(), createRequest, device, cfg, profileAPI, rsAPI, asAPI, evTime, cryptoIDs)
 }
 
-// createRoom implements /createRoom
 func createRoom(
 	ctx context.Context,
 	createRequest createRoomRequest, device *api.Device,
@@ -140,6 +155,7 @@ func createRoom(
 	profileAPI api.ClientUserAPI, rsAPI roomserverAPI.ClientRoomserverAPI,
 	asAPI appserviceAPI.AppServiceInternalAPI,
 	evTime time.Time,
+	cryptoIDs bool,
 ) util.JSONResponse {
 	userID, err := spec.NewUserID(device.UserID, true)
 	if err != nil {
@@ -225,6 +241,7 @@ func createRoom(
 		EventTime:       evTime,
 	}
 
+	if !cryptoIDs {
 		roomAlias, createRes := rsAPI.PerformCreateRoom(ctx, *userID, *roomID, &req)
 		if createRes != nil {
 			return *createRes
@@ -239,4 +256,27 @@ func createRoom(
 			Code: 200,
 			JSON: response,
 		}
+	} else {
+		req.SenderID = createRequest.CryptoID
+		createEvents, err := rsAPI.PerformCreateRoomCryptoIDs(ctx, *userID, *roomID, &req)
+		if err != nil {
+			util.GetLogger(ctx).WithError(err).Error("MakeCreateRoomEvents failed")
+			return util.JSONResponse{
+				Code: http.StatusInternalServerError,
+				JSON: spec.InternalServerError{Err: err.Error()},
+			}
+		}
+
+		response := createRoomCryptoIDsResponse{
+			RoomID:  roomID.String(),
+			Version: string(roomVersion),
+			PDUs:    ToProtoEvents(ctx, createEvents, rsAPI),
+		}
+
+		return util.JSONResponse{
+			Code: 200,
+			JSON: response,
+		}
+	}
+
 }

clientapi/routing/joinroom.go

@@ -27,6 +27,7 @@ import (
 	"github.com/matrix-org/gomatrix"
 	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
+	"github.com/sirupsen/logrus"
 )
 
 func JoinRoomByIDOrAlias(
@@ -144,3 +145,139 @@ func JoinRoomByIDOrAlias(
 		return result
 	}
 }
+
+type joinRoomCryptoIDsResponse struct {
+	RoomID    string          `json:"room_id"`
+	Version   string          `json:"room_version"`
+	ViaServer string          `json:"via_server"`
+	PDU       json.RawMessage `json:"pdu"`
+}
+
+func JoinRoomByIDOrAliasCryptoIDs(
+	req *http.Request,
+	device *api.Device,
+	rsAPI roomserverAPI.ClientRoomserverAPI,
+	profileAPI api.ClientUserAPI,
+	roomIDOrAlias string,
+) util.JSONResponse {
+	// Prepare to ask the roomserver to perform the room join.
+	joinReq := roomserverAPI.PerformJoinRequest{
+		RoomIDOrAlias: roomIDOrAlias,
+		UserID:        device.UserID,
+		IsGuest:       device.AccountType == api.AccountTypeGuest,
+		Content:       map[string]interface{}{},
+	}
+
+	// Check to see if any ?server_name= query parameters were
+	// given in the request.
+	if serverNames, ok := req.URL.Query()["server_name"]; ok {
+		for _, serverName := range serverNames {
+			joinReq.ServerNames = append(
+				joinReq.ServerNames,
+				spec.ServerName(serverName),
+			)
+		}
+	}
+
+	// If content was provided in the request then include that
+	// in the request. It'll get used as a part of the membership
+	// event content.
+	_ = httputil.UnmarshalJSONRequest(req, &joinReq.Content)
+
+	if senderid, ok := joinReq.Content["cryptoid"]; ok {
+		logrus.Errorf("CryptoID: %s", senderid.(string))
+		joinReq.SenderID = spec.SenderID(senderid.(string))
+	} else {
+		return util.JSONResponse{
+			Code: http.StatusBadRequest,
+			JSON: spec.Unknown("Missing cryptoid in request body"),
+		}
+	}
+	delete(joinReq.Content, "cryptoid")
+
+	// Work out our localpart for the client profile request.
+
+	// Request our profile content to populate the request content with.
+	profile, err := profileAPI.QueryProfile(req.Context(), device.UserID)
+
+	switch err {
+	case nil:
+		joinReq.Content["displayname"] = profile.DisplayName
+		joinReq.Content["avatar_url"] = profile.AvatarURL
+	case appserviceAPI.ErrProfileNotExists:
+		util.GetLogger(req.Context()).Error("Unable to query user profile, no profile found.")
+		return util.JSONResponse{
+			Code: http.StatusInternalServerError,
+			JSON: spec.Unknown("Unable to query user profile, no profile found."),
+		}
+	default:
+	}
+
+	// Ask the roomserver to perform the join.
+	done := make(chan util.JSONResponse, 1)
+	go func() {
+		defer close(done)
+		joinEvent, roomID, version, serverName, err := rsAPI.PerformJoinCryptoIDs(req.Context(), &joinReq)
+		var response util.JSONResponse
+
+		switch e := err.(type) {
+		case nil: // success case
+			response = util.JSONResponse{
+				Code: http.StatusOK,
+				JSON: joinRoomCryptoIDsResponse{
+					RoomID:    roomID,
+					Version:   string(version),
+					ViaServer: string(serverName),
+					PDU:       json.RawMessage(joinEvent.JSON()),
+				},
+			}
+		case roomserverAPI.ErrInvalidID:
+			response = util.JSONResponse{
+				Code: http.StatusBadRequest,
+				JSON: spec.Unknown(e.Error()),
+			}
+		case roomserverAPI.ErrNotAllowed:
+			jsonErr := spec.Forbidden(e.Error())
+			if device.AccountType == api.AccountTypeGuest {
+				jsonErr = spec.GuestAccessForbidden(e.Error())
+			}
+			response = util.JSONResponse{
+				Code: http.StatusForbidden,
+				JSON: jsonErr,
+			}
+		case *gomatrix.HTTPError: // this ensures we proxy responses over federation to the client
+			response = util.JSONResponse{
+				Code: e.Code,
+				JSON: json.RawMessage(e.Message),
+			}
+		case eventutil.ErrRoomNoExists:
+			response = util.JSONResponse{
+				Code: http.StatusNotFound,
+				JSON: spec.NotFound(e.Error()),
+			}
+		default:
+			response = util.JSONResponse{
+				Code: http.StatusInternalServerError,
+				JSON: spec.InternalServerError{},
+			}
+		}
+		done <- response
+	}()
+
+	// Wait either for the join to finish, or for us to hit a reasonable
+	// timeout, at which point we'll just return a 200 to placate clients.
+	timer := time.NewTimer(time.Second * 20)
+	select {
+	case <-timer.C:
+		return util.JSONResponse{
+			Code: http.StatusRequestTimeout,
+			JSON: spec.Unknown("Failed creating join event with the remote server."),
+		}
+	case result := <-done:
+		// Stop and drain the timer
+		if !timer.Stop() {
+			<-timer.C
+		}
+		return result
+	}
+}

clientapi/routing/joinroom_test.go

@@ -67,7 +67,7 @@ func TestJoinRoomByIDOrAlias(t *testing.T) {
 			Preset:        spec.PresetPublicChat,
 			RoomAliasName: "alias",
 			Invite:        []string{bob.ID},
-		}, aliceDev, &cfg.ClientAPI, userAPI, rsAPI, asAPI, time.Now())
+		}, aliceDev, &cfg.ClientAPI, userAPI, rsAPI, asAPI, time.Now(), false)
 		crResp, ok := resp.JSON.(createRoomResponse)
 		if !ok {
 			t.Fatalf("response is not a createRoomResponse: %+v", resp)
@@ -81,7 +81,7 @@ func TestJoinRoomByIDOrAlias(t *testing.T) {
 			Visibility: "public",
 			Preset:     spec.PresetPublicChat,
 			Invite:     []string{charlie.ID},
-		}, aliceDev, &cfg.ClientAPI, userAPI, rsAPI, asAPI, time.Now())
+		}, aliceDev, &cfg.ClientAPI, userAPI, rsAPI, asAPI, time.Now(), false)
 		crRespWithGuestAccess, ok := resp.JSON.(createRoomResponse)
 		if !ok {
 			t.Fatalf("response is not a createRoomResponse: %+v", resp)

clientapi/routing/keys.go

@@ -97,6 +97,92 @@ type queryKeysRequest struct {
 	DeviceKeys map[string][]string `json:"device_keys"`
 }
 
+type uploadKeysCryptoIDsRequest struct {
+	DeviceKeys       json.RawMessage            `json:"device_keys"`
+	OneTimeKeys      map[string]json.RawMessage `json:"one_time_keys"`
+	OneTimeCryptoIDs map[string]json.RawMessage `json:"one_time_cryptoids"`
+}
+
+func UploadKeysCryptoIDs(req *http.Request, keyAPI api.ClientKeyAPI, device *api.Device) util.JSONResponse {
+	var r uploadKeysCryptoIDsRequest
+	resErr := httputil.UnmarshalJSONRequest(req, &r)
+	if resErr != nil {
+		return *resErr
+	}
+
+	uploadReq := &api.PerformUploadKeysRequest{
+		DeviceID: device.ID,
+		UserID:   device.UserID,
+	}
+	if r.DeviceKeys != nil {
+		uploadReq.DeviceKeys = []api.DeviceKeys{
+			{
+				DeviceID: device.ID,
+				UserID:   device.UserID,
+				KeyJSON:  r.DeviceKeys,
+			},
+		}
+	}
+	if r.OneTimeKeys != nil {
+		uploadReq.OneTimeKeys = []api.OneTimeKeys{
+			{
+				DeviceID: device.ID,
+				UserID:   device.UserID,
+				KeyJSON:  r.OneTimeKeys,
+			},
+		}
+	}
+	if r.OneTimeCryptoIDs != nil {
+		uploadReq.OneTimeCryptoIDs = []api.OneTimeCryptoIDs{
+			{
+				UserID:  device.UserID,
+				KeyJSON: r.OneTimeCryptoIDs,
+			},
+		}
+	}
+
+	util.GetLogger(req.Context()).
+		WithField("device keys", r.DeviceKeys).
+		WithField("one-time keys", r.OneTimeKeys).
+		WithField("one-time cryptoids", r.OneTimeCryptoIDs).
+		Info("Uploading keys")
+
+	var uploadRes api.PerformUploadKeysResponse
+	if err := keyAPI.PerformUploadKeys(req.Context(), uploadReq, &uploadRes); err != nil {
+		return util.ErrorResponse(err)
+	}
+	if uploadRes.Error != nil {
+		util.GetLogger(req.Context()).WithError(uploadRes.Error).Error("Failed to PerformUploadKeys")
+		return util.JSONResponse{
+			Code: http.StatusInternalServerError,
+			JSON: spec.InternalServerError{},
+		}
+	}
+	if len(uploadRes.KeyErrors) > 0 {
+		util.GetLogger(req.Context()).WithField("key_errors", uploadRes.KeyErrors).Error("Failed to upload one or more keys")
+		return util.JSONResponse{
+			Code: 400,
+			JSON: uploadRes.KeyErrors,
+		}
+	}
+
+	keyCount := make(map[string]int)
+	if len(uploadRes.OneTimeKeyCounts) > 0 {
+		keyCount = uploadRes.OneTimeKeyCounts[0].KeyCount
+	}
+	cryptoIDCount := make(map[string]int)
+	if len(uploadRes.OneTimeCryptoIDCounts) > 0 {
+		cryptoIDCount = uploadRes.OneTimeCryptoIDCounts[0].KeyCount
+	}
+	return util.JSONResponse{
+		Code: 200,
+		JSON: struct {
+			OTKCounts  interface{} `json:"one_time_key_counts"`
+			OTIDCounts interface{} `json:"one_time_cryptoid_counts"`
+		}{keyCount, cryptoIDCount},
+	}
+}
+
 func (r *queryKeysRequest) GetTimeout() time.Duration {
 	if r.Timeout == 0 {
 		return 10 * time.Second

clientapi/routing/leaveroom.go

@@ -15,6 +15,7 @@
 package routing
 
 import (
+	"encoding/json"
 	"net/http"
 
 	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
@@ -23,11 +24,16 @@ import (
 	"github.com/matrix-org/util"
 )
 
+type leaveRoomCryptoIDsResponse struct {
+	PDU json.RawMessage `json:"pdu"`
+}
+
 func LeaveRoomByID(
 	req *http.Request,
 	device *api.Device,
 	rsAPI roomserverAPI.ClientRoomserverAPI,
 	roomID string,
+	cryptoIDs bool,
 ) util.JSONResponse {
 	userID, err := spec.NewUserID(device.UserID, true)
 	if err != nil {
@@ -45,7 +51,8 @@ func LeaveRoomByID(
 	leaveRes := roomserverAPI.PerformLeaveResponse{}
 
 	// Ask the roomserver to perform the leave.
-	if err := rsAPI.PerformLeave(req.Context(), &leaveReq, &leaveRes); err != nil {
+	leaveEvent, err := rsAPI.PerformLeave(req.Context(), &leaveReq, &leaveRes, cryptoIDs)
+	if err != nil {
 		if leaveRes.Code != 0 {
 			return util.JSONResponse{
 				Code: leaveRes.Code,
@@ -58,8 +65,15 @@ func LeaveRoomByID(
 		}
 	}
 
+	if cryptoIDs {
+		return util.JSONResponse{
+			Code: http.StatusOK,
+			JSON: leaveRoomCryptoIDsResponse{
+				PDU: json.RawMessage(leaveEvent.JSON()),
+			},
+		}
+	}
 	return util.JSONResponse{
 		Code: http.StatusOK,
-		JSON: struct{}{},
 	}
 }

clientapi/routing/membership.go

@@ -17,6 +17,7 @@ package routing
 import (
 	"context"
 	"crypto/ed25519"
+	"encoding/json"
 	"fmt"
 	"net/http"
 	"time"
@@ -39,10 +40,15 @@ import (
 	"github.com/matrix-org/util"
 )
 
+type membershipCryptoIDsResponse struct {
+	PDU json.RawMessage `json:"pdu"`
+}
+
 func SendBan(
 	req *http.Request, profileAPI userapi.ClientUserAPI, device *userapi.Device,
 	roomID string, cfg *config.ClientAPI,
 	rsAPI roomserverAPI.ClientRoomserverAPI, asAPI appserviceAPI.AppServiceInternalAPI,
+	cryptoIDs bool,
 ) util.JSONResponse {
 	body, evTime, reqErr := extractRequestData(req)
 	if reqErr != nil {
@@ -95,13 +101,14 @@ func SendBan(
 		}
 	}
 
-	return sendMembership(req.Context(), profileAPI, device, roomID, spec.Ban, body.Reason, cfg, body.UserID, evTime, rsAPI, asAPI)
+	return sendMembership(req.Context(), profileAPI, device, roomID, spec.Ban, body.Reason, cfg, body.UserID, evTime, rsAPI, asAPI, cryptoIDs)
 }
 
 func sendMembership(ctx context.Context, profileAPI userapi.ClientUserAPI, device *userapi.Device,
 	roomID, membership, reason string, cfg *config.ClientAPI, targetUserID string, evTime time.Time,
-	rsAPI roomserverAPI.ClientRoomserverAPI, asAPI appserviceAPI.AppServiceInternalAPI) util.JSONResponse {
+	rsAPI roomserverAPI.ClientRoomserverAPI, asAPI appserviceAPI.AppServiceInternalAPI, cryptoIDs bool) util.JSONResponse {
 
+	// TODO: cryptoIDs - what about when we don't know the senderID for a user?
 	event, err := buildMembershipEvent(
 		ctx, targetUserID, reason, profileAPI, device, membership,
 		roomID, false, cfg, evTime, rsAPI, asAPI,
@@ -114,6 +121,8 @@ func sendMembership(ctx context.Context, profileAPI userapi.ClientUserAPI, devic
 		}
 	}
 
+	var json interface{}
+	if !cryptoIDs {
 		serverName := device.UserDomain()
 		if err = roomserverAPI.SendEvents(
 			ctx, rsAPI,
@@ -131,10 +140,14 @@ func sendMembership(ctx context.Context, profileAPI userapi.ClientUserAPI, devic
 				JSON: spec.InternalServerError{},
 			}
 		}
+		json = struct{}{}
+	} else {
+		json = membershipCryptoIDsResponse{PDU: event.JSON()}
+	}
 
 	return util.JSONResponse{
 		Code: http.StatusOK,
-		JSON: struct{}{},
+		JSON: json,
 	}
 }
 
@@ -142,6 +155,7 @@ func SendKick(
 	req *http.Request, profileAPI userapi.ClientUserAPI, device *userapi.Device,
 	roomID string, cfg *config.ClientAPI,
 	rsAPI roomserverAPI.ClientRoomserverAPI, asAPI appserviceAPI.AppServiceInternalAPI,
+	cryptoIDs bool,
 ) util.JSONResponse {
 	body, evTime, reqErr := extractRequestData(req)
 	if reqErr != nil {
@@ -216,13 +230,14 @@ func SendKick(
 		}
 	}
 	// TODO: should we be using SendLeave instead?
-	return sendMembership(req.Context(), profileAPI, device, roomID, spec.Leave, body.Reason, cfg, body.UserID, evTime, rsAPI, asAPI)
+	return sendMembership(req.Context(), profileAPI, device, roomID, spec.Leave, body.Reason, cfg, body.UserID, evTime, rsAPI, asAPI, cryptoIDs)
 }
 
 func SendUnban(
 	req *http.Request, profileAPI userapi.ClientUserAPI, device *userapi.Device,
 	roomID string, cfg *config.ClientAPI,
 	rsAPI roomserverAPI.ClientRoomserverAPI, asAPI appserviceAPI.AppServiceInternalAPI,
+	cryptoIDs bool,
 ) util.JSONResponse {
 	body, evTime, reqErr := extractRequestData(req)
 	if reqErr != nil {
@@ -272,13 +287,14 @@ func SendUnban(
 		}
 	}
 	// TODO: should we be using SendLeave instead?
-	return sendMembership(req.Context(), profileAPI, device, roomID, spec.Leave, body.Reason, cfg, body.UserID, evTime, rsAPI, asAPI)
+	return sendMembership(req.Context(), profileAPI, device, roomID, spec.Leave, body.Reason, cfg, body.UserID, evTime, rsAPI, asAPI, cryptoIDs)
 }
 
 func SendInvite(
 	req *http.Request, profileAPI userapi.ClientUserAPI, device *userapi.Device,
 	roomID string, cfg *config.ClientAPI,
 	rsAPI roomserverAPI.ClientRoomserverAPI, asAPI appserviceAPI.AppServiceInternalAPI,
+	cryptoIDs bool,
 ) util.JSONResponse {
 	body, evTime, reqErr := extractRequestData(req)
 	if reqErr != nil {
@@ -323,7 +339,7 @@ func SendInvite(
 	}
 
 	// We already received the return value, so no need to check for an error here.
-	response, _ := sendInvite(req.Context(), profileAPI, device, roomID, body.UserID, body.Reason, cfg, rsAPI, asAPI, evTime)
+	response, _ := sendInvite(req.Context(), profileAPI, device, roomID, body.UserID, body.Reason, cfg, rsAPI, asAPI, evTime, cryptoIDs)
 	return response
 }
 
@@ -336,6 +352,7 @@ func sendInvite(
 	cfg *config.ClientAPI,
 	rsAPI roomserverAPI.ClientRoomserverAPI,
 	asAPI appserviceAPI.AppServiceInternalAPI, evTime time.Time,
+	cryptoIDs bool,
 ) (util.JSONResponse, error) {
 	validRoomID, err := spec.NewRoomID(roomID)
 	if err != nil {
@@ -372,7 +389,7 @@ func sendInvite(
 			JSON: spec.InternalServerError{},
 		}, err
 	}
-	err = rsAPI.PerformInvite(ctx, &api.PerformInviteRequest{
+	inviteEvent, err := rsAPI.PerformInvite(ctx, &api.PerformInviteRequest{
 		InviteInput: roomserverAPI.InviteInput{
 			RoomID:      *validRoomID,
 			Inviter:     *inviter,
@@ -387,7 +404,7 @@ func sendInvite(
 		},
 		InviteRoomState: nil, // ask the roomserver to draw up invite room state for us
 		SendAsServer:    string(device.UserDomain()),
-	})
+	}, cryptoIDs)
 
 	switch e := err.(type) {
 	case roomserverAPI.ErrInvalidID:
@@ -410,10 +427,22 @@ func sendInvite(
 		}, err
 	}
 
-	return util.JSONResponse{
+	response := util.JSONResponse{
 		Code: http.StatusOK,
 		JSON: struct{}{},
-	}, nil
+	}
+
+	type inviteCryptoIDResponse struct {
+		PDU json.RawMessage `json:"pdu"`
+	}
+
+	if inviteEvent != nil {
+		response.JSON = inviteCryptoIDResponse{
+			PDU: json.RawMessage(inviteEvent.JSON()),
+		}
+	}
+
+	return response, nil
 }
 
 func buildMembershipEventDirect(

clientapi/routing/routing.go

@@ -309,9 +309,33 @@ func Setup(
 
 	v3mux.Handle("/createRoom",
 		httputil.MakeAuthAPI("createRoom", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
-			return CreateRoom(req, device, cfg, userAPI, rsAPI, asAPI)
+			return CreateRoom(req, device, cfg, userAPI, rsAPI, asAPI, false)
 		}),
 	).Methods(http.MethodPost, http.MethodOptions)
+	unstableMux.Handle("/org.matrix.msc4080/createRoom",
+		httputil.MakeAuthAPI("createRoom", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			logrus.Info("Processing request to /org.matrix.msc4080/createRoom")
+			return CreateRoom(req, device, cfg, userAPI, rsAPI, asAPI, true)
+		}),
+	).Methods(http.MethodPost, http.MethodOptions)
+	unstableMux.Handle("/org.matrix.msc4080/send_pdus/{txnID}",
+		httputil.MakeAuthAPI("send_pdus", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			logrus.Info("Processing request to /org.matrix.msc4080/send_pdus")
+			if r := rateLimits.Limit(req, device); r != nil {
+				return *r
+			}
+
+			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
+			if err != nil {
+				return util.ErrorResponse(err)
+			}
+			txnID := vars["txnID"]
+
+			// NOTE: when making events such as for create_room, multiple PDUs will need to be passed between the client & server.
+			return SendPDUs(req, device, cfg, userAPI, rsAPI, asAPI, &txnID)
+		}),
+	).Methods(http.MethodPost, http.MethodOptions)
+
 	v3mux.Handle("/join/{roomIDOrAlias}",
 		httputil.MakeAuthAPI(spec.Join, userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			if r := rateLimits.Limit(req, device); r != nil {
@@ -334,8 +358,32 @@ func Setup(
 			return resp.(util.JSONResponse)
 		}, httputil.WithAllowGuests()),
 	).Methods(http.MethodPost, http.MethodOptions)
+	unstableMux.Handle("/org.matrix.msc4080/join/{roomIDOrAlias}",
+		httputil.MakeAuthAPI(spec.Join, userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			logrus.Info("Processing request to /org.matrix.msc4080/join/{roomIDOrAlias}")
+			if r := rateLimits.Limit(req, device); r != nil {
+				return *r
+			}
+			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
+			if err != nil {
+				return util.ErrorResponse(err)
+			}
+			// Only execute a join for roomIDOrAlias and UserID once. If there is a join in progress
+			// it waits for it to complete and returns that result for subsequent requests.
+			resp, _, _ := sf.Do(vars["roomIDOrAlias"]+device.UserID, func() (any, error) {
+				return JoinRoomByIDOrAliasCryptoIDs(
+					req, device, rsAPI, userAPI, vars["roomIDOrAlias"],
+				), nil
+			})
+			// once all joins are processed, drop them from the cache. Further requests
+			// will be processed as usual.
+			sf.Forget(vars["roomIDOrAlias"] + device.UserID)
+			return resp.(util.JSONResponse)
+		}, httputil.WithAllowGuests()),
+	).Methods(http.MethodPost, http.MethodOptions)
 
 	if mscCfg.Enabled("msc2753") {
+		// TODO: update for cryptoIDs
 		v3mux.Handle("/peek/{roomIDOrAlias}",
 			httputil.MakeAuthAPI(spec.Peek, userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 				if r := rateLimits.Limit(req, device); r != nil {
@@ -378,6 +426,29 @@ func Setup(
 			return resp.(util.JSONResponse)
 		}, httputil.WithAllowGuests()),
 	).Methods(http.MethodPost, http.MethodOptions)
+	unstableMux.Handle("/org.matrix.msc4080/rooms/{roomID}/join",
+		httputil.MakeAuthAPI(spec.Join, userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			logrus.Info("Processing request to /org.matrix.msc4080/rooms/{roomID}/join")
+			if r := rateLimits.Limit(req, device); r != nil {
+				return *r
+			}
+			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
+			if err != nil {
+				return util.ErrorResponse(err)
+			}
+			// Only execute a join for roomID and UserID once. If there is a join in progress
+			// it waits for it to complete and returns that result for subsequent requests.
+			resp, _, _ := sf.Do(vars["roomID"]+device.UserID, func() (any, error) {
+				return JoinRoomByIDOrAliasCryptoIDs(
+					req, device, rsAPI, userAPI, vars["roomID"],
+				), nil
+			})
+			// once all joins are processed, drop them from the cache. Further requests
+			// will be processed as usual.
+			sf.Forget(vars["roomID"] + device.UserID)
+			return resp.(util.JSONResponse)
+		}, httputil.WithAllowGuests()),
+	).Methods(http.MethodPost, http.MethodOptions)
 	v3mux.Handle("/rooms/{roomID}/leave",
 		httputil.MakeAuthAPI("membership", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			if r := rateLimits.Limit(req, device); r != nil {
@@ -388,10 +459,26 @@ func Setup(
 				return util.ErrorResponse(err)
 			}
 			return LeaveRoomByID(
-				req, device, rsAPI, vars["roomID"],
+				req, device, rsAPI, vars["roomID"], false,
 			)
 		}, httputil.WithAllowGuests()),
 	).Methods(http.MethodPost, http.MethodOptions)
+	unstableMux.Handle("/org.matrix.msc4080/rooms/{roomID}/leave",
+		httputil.MakeAuthAPI("membership", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			logrus.Info("Processing request to /org.matrix.msc4080/rooms/{roomID}/leave")
+			if r := rateLimits.Limit(req, device); r != nil {
+				return *r
+			}
+			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
+			if err != nil {
+				return util.ErrorResponse(err)
+			}
+			return LeaveRoomByID(
+				req, device, rsAPI, vars["roomID"], true,
+			)
+		}, httputil.WithAllowGuests()),
+	).Methods(http.MethodPost, http.MethodOptions)
+	// TODO: update for cryptoIDs
 	v3mux.Handle("/rooms/{roomID}/unpeek",
 		httputil.MakeAuthAPI("unpeek", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
@@ -409,7 +496,17 @@ func Setup(
 			if err != nil {
 				return util.ErrorResponse(err)
 			}
-			return SendBan(req, userAPI, device, vars["roomID"], cfg, rsAPI, asAPI)
+			return SendBan(req, userAPI, device, vars["roomID"], cfg, rsAPI, asAPI, false)
+		}),
+	).Methods(http.MethodPost, http.MethodOptions)
+	unstableMux.Handle("/org.matrix.msc4080/rooms/{roomID}/ban",
+		httputil.MakeAuthAPI("membership", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			logrus.Info("Processing request to /org.matrix.msc4080/rooms/{roomID}/ban")
+			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
+			if err != nil {
+				return util.ErrorResponse(err)
+			}
+			return SendBan(req, userAPI, device, vars["roomID"], cfg, rsAPI, asAPI, true)
 		}),
 	).Methods(http.MethodPost, http.MethodOptions)
 	v3mux.Handle("/rooms/{roomID}/invite",
@@ -421,7 +518,20 @@ func Setup(
 			if err != nil {
 				return util.ErrorResponse(err)
 			}
-			return SendInvite(req, userAPI, device, vars["roomID"], cfg, rsAPI, asAPI)
+			return SendInvite(req, userAPI, device, vars["roomID"], cfg, rsAPI, asAPI, false)
+		}),
+	).Methods(http.MethodPost, http.MethodOptions)
+	unstableMux.Handle("/org.matrix.msc4080/rooms/{roomID}/invite",
+		httputil.MakeAuthAPI("membership", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			logrus.Info("Processing request to /org.matrix.msc4080/rooms/{roomID}/invite")
+			if r := rateLimits.Limit(req, device); r != nil {
+				return *r
+			}
+			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
+			if err != nil {
+				return util.ErrorResponse(err)
+			}
+			return SendInvite(req, userAPI, device, vars["roomID"], cfg, rsAPI, asAPI, true)
 		}),
 	).Methods(http.MethodPost, http.MethodOptions)
 	v3mux.Handle("/rooms/{roomID}/kick",
@@ -430,7 +540,17 @@ func Setup(
 			if err != nil {
 				return util.ErrorResponse(err)
 			}
-			return SendKick(req, userAPI, device, vars["roomID"], cfg, rsAPI, asAPI)
+			return SendKick(req, userAPI, device, vars["roomID"], cfg, rsAPI, asAPI, false)
+		}),
+	).Methods(http.MethodPost, http.MethodOptions)
+	unstableMux.Handle("/org.matrix.msc4080/rooms/{roomID}/kick",
+		httputil.MakeAuthAPI("membership", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			logrus.Info("Processing request to /org.matrix.msc4080/rooms/{roomID}/kick")
+			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
+			if err != nil {
+				return util.ErrorResponse(err)
+			}
+			return SendKick(req, userAPI, device, vars["roomID"], cfg, rsAPI, asAPI, true)
 		}),
 	).Methods(http.MethodPost, http.MethodOptions)
 	v3mux.Handle("/rooms/{roomID}/unban",
@@ -439,7 +559,17 @@ func Setup(
 			if err != nil {
 				return util.ErrorResponse(err)
 			}
-			return SendUnban(req, userAPI, device, vars["roomID"], cfg, rsAPI, asAPI)
+			return SendUnban(req, userAPI, device, vars["roomID"], cfg, rsAPI, asAPI, false)
+		}),
+	).Methods(http.MethodPost, http.MethodOptions)
+	unstableMux.Handle("/org.matrix.msc4080/rooms/{roomID}/unban",
+		httputil.MakeAuthAPI("membership", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			logrus.Info("Processing request to /org.matrix.msc4080/rooms/{roomID}/unban")
+			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
+			if err != nil {
+				return util.ErrorResponse(err)
+			}
+			return SendUnban(req, userAPI, device, vars["roomID"], cfg, rsAPI, asAPI, true)
 		}),
 	).Methods(http.MethodPost, http.MethodOptions)
 	v3mux.Handle("/rooms/{roomID}/send/{eventType}",
@@ -451,6 +581,16 @@ func Setup(
 			return SendEvent(req, device, vars["roomID"], vars["eventType"], nil, nil, cfg, rsAPI, nil)
 		}, httputil.WithAllowGuests()),
 	).Methods(http.MethodPost, http.MethodOptions)
+	unstableMux.Handle("/org.matrix.msc4080/rooms/{roomID}/send/{eventType}",
+		httputil.MakeAuthAPI("send_message", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			logrus.Info("Processing request to /org.matrix.msc4080/rooms/{roomID}/send/{eventType}")
+			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
+			if err != nil {
+				return util.ErrorResponse(err)
+			}
+			return SendEventCryptoIDs(req, device, vars["roomID"], vars["eventType"], nil, nil, cfg, rsAPI, nil)
+		}, httputil.WithAllowGuests()),
+	).Methods(http.MethodPost, http.MethodOptions)
 	v3mux.Handle("/rooms/{roomID}/send/{eventType}/{txnID}",
 		httputil.MakeAuthAPI("send_message", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
@@ -462,6 +602,18 @@ func Setup(
 				nil, cfg, rsAPI, transactionsCache)
 		}, httputil.WithAllowGuests()),
 	).Methods(http.MethodPut, http.MethodOptions)
+	unstableMux.Handle("/org.matrix.msc4080/rooms/{roomID}/send/{eventType}/{txnID}",
+		httputil.MakeAuthAPI("send_message", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			logrus.Info("Processing request to /org.matrix.msc4080/rooms/{roomID}/send/{eventType}/{txnID}")
+			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
+			if err != nil {
+				return util.ErrorResponse(err)
+			}
+			txnID := vars["txnID"]
+			return SendEventCryptoIDs(req, device, vars["roomID"], vars["eventType"], &txnID,
+				nil, cfg, rsAPI, transactionsCache)
+		}, httputil.WithAllowGuests()),
+	).Methods(http.MethodPut, http.MethodOptions)
 
 	v3mux.Handle("/rooms/{roomID}/state", httputil.MakeAuthAPI("room_state", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 		vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
@@ -510,6 +662,18 @@ func Setup(
 			return SendEvent(req, device, vars["roomID"], eventType, nil, &emptyString, cfg, rsAPI, nil)
 		}, httputil.WithAllowGuests()),
 	).Methods(http.MethodPut, http.MethodOptions)
+	unstableMux.Handle("/org.matrix.msc4080/rooms/{roomID}/state/{eventType:[^/]+/?}",
+		httputil.MakeAuthAPI("send_message", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			logrus.Info("Processing request to /org.matrix.msc4080/rooms/{roomID}/state/{eventType:[^/]+/?}")
+			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
+			if err != nil {
+				return util.ErrorResponse(err)
+			}
+			emptyString := ""
+			eventType := strings.TrimSuffix(vars["eventType"], "/")
+			return SendEventCryptoIDs(req, device, vars["roomID"], eventType, nil, &emptyString, cfg, rsAPI, nil)
+		}, httputil.WithAllowGuests()),
+	).Methods(http.MethodPut, http.MethodOptions)
 
 	v3mux.Handle("/rooms/{roomID}/state/{eventType}/{stateKey}",
 		httputil.MakeAuthAPI("send_message", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
@@ -521,6 +685,17 @@ func Setup(
 			return SendEvent(req, device, vars["roomID"], vars["eventType"], nil, &stateKey, cfg, rsAPI, nil)
 		}, httputil.WithAllowGuests()),
 	).Methods(http.MethodPut, http.MethodOptions)
+	unstableMux.Handle("/org.matrix.msc4080/rooms/{roomID}/state/{eventType}/{stateKey}",
+		httputil.MakeAuthAPI("send_message", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			logrus.Info("Processing request to /org.matrix.msc4080/rooms/{roomID}/state/{eventType}/{stateKey}")
+			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
+			if err != nil {
+				return util.ErrorResponse(err)
+			}
+			stateKey := vars["stateKey"]
+			return SendEventCryptoIDs(req, device, vars["roomID"], vars["eventType"], nil, &stateKey, cfg, rsAPI, nil)
+		}, httputil.WithAllowGuests()),
+	).Methods(http.MethodPut, http.MethodOptions)
 
 	// Defined outside of handler to persist between calls
 	// TODO: clear based on some criteria
@@ -559,6 +734,7 @@ func Setup(
 		}),
 	).Methods(http.MethodGet, http.MethodOptions)
 
+	// TODO: update for cryptoIDs
 	v3mux.Handle("/directory/room/{roomAlias}",
 		httputil.MakeAuthAPI("directory_room", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
@@ -569,6 +745,7 @@ func Setup(
 		}),
 	).Methods(http.MethodPut, http.MethodOptions)
 
+	// TODO: update for cryptoIDs
 	v3mux.Handle("/directory/room/{roomAlias}",
 		httputil.MakeAuthAPI("directory_room", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
@@ -636,6 +813,7 @@ func Setup(
 		}),
 	).Methods(http.MethodPost, http.MethodOptions)
 
+	// TODO: update for cryptoIDs
 	v3mux.Handle("/rooms/{roomID}/typing/{userID}",
 		httputil.MakeAuthAPI("rooms_typing", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			if r := rateLimits.Limit(req, device); r != nil {
@@ -648,6 +826,7 @@ func Setup(
 			return SendTyping(req, device, vars["roomID"], vars["userID"], rsAPI, syncProducer)
 		}),
 	).Methods(http.MethodPut, http.MethodOptions)
+	// TODO: update for cryptoIDs
 	v3mux.Handle("/rooms/{roomID}/redact/{eventID}",
 		httputil.MakeAuthAPI("rooms_redact", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
@@ -657,6 +836,7 @@ func Setup(
 			return SendRedaction(req, device, vars["roomID"], vars["eventID"], cfg, rsAPI, nil, nil)
 		}),
 	).Methods(http.MethodPost, http.MethodOptions)
+	// TODO: update for cryptoIDs
 	v3mux.Handle("/rooms/{roomID}/redact/{eventID}/{txnId}",
 		httputil.MakeAuthAPI("rooms_redact", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
@@ -668,6 +848,7 @@ func Setup(
 		}),
 	).Methods(http.MethodPut, http.MethodOptions)
 
+	// TODO: update for cryptoIDs
 	v3mux.Handle("/sendToDevice/{eventType}/{txnID}",
 		httputil.MakeAuthAPI("send_to_device", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
@@ -1118,6 +1299,7 @@ func Setup(
 		}),
 	).Methods(http.MethodPost, http.MethodOptions)
 
+	// TODO: update for cryptoIDs
 	v3mux.Handle("/rooms/{roomID}/read_markers",
 		httputil.MakeAuthAPI("rooms_read_markers", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			if r := rateLimits.Limit(req, device); r != nil {
@@ -1144,6 +1326,7 @@ func Setup(
 		}),
 	).Methods(http.MethodPost, http.MethodOptions)
 
+	// TODO: update for cryptoIDs
 	v3mux.Handle("/rooms/{roomID}/upgrade",
 		httputil.MakeAuthAPI("rooms_upgrade", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
@@ -1472,6 +1655,12 @@ func Setup(
 			return UploadKeys(req, userAPI, device)
 		}, httputil.WithAllowGuests()),
 	).Methods(http.MethodPost, http.MethodOptions)
+	unstableMux.Handle("/org.matrix.msc4080/keys/upload",
+		httputil.MakeAuthAPI("keys_upload", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			logrus.Info("Processing request to /org.matrix.msc4080/keys/upload")
+			return UploadKeysCryptoIDs(req, userAPI, device)
+		}, httputil.WithAllowGuests()),
+	).Methods(http.MethodPost, http.MethodOptions)
 	v3mux.Handle("/keys/query",
 		httputil.MakeAuthAPI("keys_query", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			return QueryKeys(req, userAPI, device)
@@ -1495,6 +1684,7 @@ func Setup(
 			return SetReceipt(req, userAPI, syncProducer, device, vars["roomId"], vars["receiptType"], vars["eventId"])
 		}),
 	).Methods(http.MethodPost, http.MethodOptions)
+	// TODO: update for cryptoIDs
 	v3mux.Handle("/presence/{userId}/status",
 		httputil.MakeAuthAPI("set_presence", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))

clientapi/routing/send_pdus.go

@@ -0,0 +1,272 @@
+// 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.
+
+package routing
+
+import (
+	"encoding/json"
+	"net/http"
+	"sync"
+	"time"
+
+	appserviceAPI "github.com/matrix-org/dendrite/appservice/api"
+	"github.com/matrix-org/dendrite/clientapi/httputil"
+	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
+	"github.com/matrix-org/dendrite/roomserver/types"
+	"github.com/matrix-org/dendrite/setup/config"
+	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/gomatrixserverlib/spec"
+	"github.com/matrix-org/util"
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+type PDUInfo struct {
+	Version   string          `json:"room_version"`
+	ViaServer string          `json:"via_server,omitempty"`
+	PDU       json.RawMessage `json:"pdu"`
+}
+
+type sendPDUsRequest struct {
+	PDUs []PDUInfo `json:"pdus"`
+}
+
+// SendPDUs implements /sendPDUs
+// nolint:gocyclo
+func SendPDUs(
+	req *http.Request, device *api.Device,
+	cfg *config.ClientAPI,
+	profileAPI api.ClientUserAPI, rsAPI roomserverAPI.ClientRoomserverAPI,
+	asAPI appserviceAPI.AppServiceInternalAPI,
+	txnID *string,
+) util.JSONResponse {
+	// TODO: cryptoIDs - should this include an "eventType"?
+	// if it's a bulk send endpoint, I don't think that makes any sense since there are multiple event types
+	// In that case, how do I know how to treat the events?
+	// I could sort them all by roomID?
+	// Then filter them down based on event type? (how do I collect groups of events such as for room creation?)
+	// Possibly based on event hash tracking that I know were sent to the client?
+	// For createRoom, I know what the possible list of events are, so try to find those and collect them to send to room creation.
+	// Could also sort by depth... but that seems dangerous and depth may not be a field forever
+	// Does it matter at all?
+	// Can't I just forward all the events to the roomserver?
+	// Do I need to do any specific processing on them?
+
+	var pdus sendPDUsRequest
+	resErr := httputil.UnmarshalJSONRequest(req, &pdus)
+	if resErr != nil {
+		return *resErr
+	}
+
+	userID, err := spec.NewUserID(device.UserID, true)
+	if err != nil {
+		return util.JSONResponse{
+			Code: http.StatusBadRequest,
+			JSON: spec.InvalidParam(err.Error()),
+		}
+	}
+
+	// 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
+	// TODO: cryptoIDs - where to get roomID from?
+	mutex, _ := userRoomSendMutexes.LoadOrStore("roomID"+userID.String(), &sync.Mutex{})
+	mutex.(*sync.Mutex).Lock()
+	defer mutex.(*sync.Mutex).Unlock()
+
+	inputs := make([]roomserverAPI.InputRoomEvent, 0, len(pdus.PDUs))
+	for _, event := range pdus.PDUs {
+		// TODO: cryptoIDs - event hash check?
+		verImpl, err := gomatrixserverlib.GetRoomVersion(gomatrixserverlib.RoomVersion(event.Version))
+		if err != nil {
+			return util.JSONResponse{
+				Code: http.StatusInternalServerError,
+				JSON: spec.InternalServerError{Err: err.Error()},
+			}
+		}
+		//eventJSON, err := json.Marshal(event)
+		//if err != nil {
+		//	return util.JSONResponse{
+		//		Code: http.StatusInternalServerError,
+		//		JSON: spec.InternalServerError{Err: err.Error()},
+		//	}
+		//}
+		// TODO: cryptoIDs - how should we be converting to a PDU here?
+		// if the hash matches an event we sent to the client, then the JSON should be good.
+		// But how do we know how to fill out if the event is redacted if we use the trustedJSON function?
+		// Also - untrusted JSON seems better - except it strips off the unsigned field?
+		// Also - gmsl events don't store the `hashes` field... problem?
+
+		pdu, err := verImpl.NewEventFromUntrustedJSON(event.PDU)
+		if err != nil {
+			return util.JSONResponse{
+				Code: http.StatusInternalServerError,
+				JSON: spec.InternalServerError{Err: err.Error()},
+			}
+		}
+
+		util.GetLogger(req.Context()).Infof("Processing %s event (%s): %s", pdu.Type(), pdu.EventID(), pdu.JSON())
+
+		// Check that the event is signed by the server sending the request.
+		redacted, err := verImpl.RedactEventJSON(pdu.JSON())
+		if err != nil {
+			util.GetLogger(req.Context()).WithError(err).Error("RedactEventJSON failed")
+			continue
+		}
+
+		verifier := gomatrixserverlib.JSONVerifierSelf{}
+		verifyRequests := []gomatrixserverlib.VerifyJSONRequest{{
+			ServerName:           spec.ServerName(pdu.SenderID()),
+			Message:              redacted,
+			AtTS:                 pdu.OriginServerTS(),
+			ValidityCheckingFunc: gomatrixserverlib.StrictValiditySignatureCheck,
+		}}
+		verifyResults, err := verifier.VerifyJSONs(req.Context(), verifyRequests)
+		if err != nil {
+			util.GetLogger(req.Context()).WithError(err).Error("keys.VerifyJSONs failed")
+			continue
+		}
+		if verifyResults[0].Error != nil {
+			util.GetLogger(req.Context()).WithError(verifyResults[0].Error).Error("Signature check failed: ")
+			continue
+		}
+
+		switch pdu.Type() {
+		case spec.MRoomCreate:
+		case spec.MRoomMember:
+			var membership gomatrixserverlib.MemberContent
+			err = json.Unmarshal(pdu.Content(), &membership)
+			switch {
+			case err != nil:
+				util.GetLogger(req.Context()).Errorf("m.room.member event (%s) content invalid: %v", pdu.EventID(), pdu.Content())
+				continue
+			case membership.Membership == spec.Join:
+				deviceUserID, err := spec.NewUserID(device.UserID, true)
+				if err != nil {
+					return util.JSONResponse{
+						Code: http.StatusForbidden,
+						JSON: spec.Forbidden("userID doesn't have power level to change visibility"),
+					}
+				}
+				if !cfg.Matrix.IsLocalServerName(pdu.RoomID().Domain()) {
+					queryReq := roomserverAPI.QueryMembershipForUserRequest{
+						RoomID: pdu.RoomID().String(),
+						UserID: *deviceUserID,
+					}
+					var queryRes roomserverAPI.QueryMembershipForUserResponse
+					if err := rsAPI.QueryMembershipForUser(req.Context(), &queryReq, &queryRes); err != nil {
+						util.GetLogger(req.Context()).WithError(err).Error("rsAPI.QueryMembershipsForRoom failed")
+						return util.JSONResponse{
+							Code: http.StatusInternalServerError,
+							JSON: spec.InternalServerError{},
+						}
+					}
+					if !queryRes.IsInRoom {
+						// This is a join event to a remote room
+						// TODO: cryptoIDs - figure out how to obtain unsigned contents for outstanding federated invites
+						joinReq := roomserverAPI.PerformJoinRequestCryptoIDs{
+							RoomID:      pdu.RoomID().String(),
+							UserID:      device.UserID,
+							IsGuest:     device.AccountType == api.AccountTypeGuest,
+							ServerNames: []spec.ServerName{spec.ServerName(event.ViaServer)},
+							JoinEvent:   pdu,
+						}
+						err := rsAPI.PerformSendJoinCryptoIDs(req.Context(), &joinReq)
+						if err != nil {
+							util.GetLogger(req.Context()).Errorf("Failed processing %s event (%s): %v", pdu.Type(), pdu.EventID(), err)
+						}
+						continue // NOTE: don't send this event on to the roomserver
+					}
+				}
+			case membership.Membership == spec.Invite:
+				stateKey := pdu.StateKey()
+				if stateKey == nil {
+					return util.JSONResponse{
+						Code: http.StatusForbidden,
+						JSON: spec.Forbidden("invalid state_key for membership event"),
+					}
+				}
+				invitedUserID, err := rsAPI.QueryUserIDForSender(req.Context(), pdu.RoomID(), spec.SenderID(*stateKey))
+				if err != nil || invitedUserID == nil {
+					return util.JSONResponse{
+						Code: http.StatusNotFound,
+						JSON: spec.NotFound("cannot find userID for invite event"),
+					}
+				}
+				if !cfg.Matrix.IsLocalServerName(spec.ServerName(invitedUserID.Domain())) {
+					inviteReq := roomserverAPI.PerformInviteRequestCryptoIDs{
+						RoomID:      pdu.RoomID().String(),
+						UserID:      *invitedUserID,
+						InviteEvent: pdu,
+					}
+					err := rsAPI.PerformSendInviteCryptoIDs(req.Context(), &inviteReq)
+					if err != nil {
+						util.GetLogger(req.Context()).Errorf("Failed processing %s event (%s): %v", pdu.Type(), pdu.EventID(), err)
+					}
+					continue // NOTE: don't send this event on to the roomserver
+				}
+			}
+		}
+
+		// TODO: cryptoIDs - does it matter which order these are added?
+		// yes - if the events are for room creation.
+		// Could make this a client requirement? ie. events are processed based on the order they appear
+		// We need to check event validity after processing each event.
+		// ie. what if the client changes power levels that disallow further events they sent?
+		// We should be doing this already as part of `SendInputRoomEvents`, but how should we pass this
+		// failure back to the client?
+
+		var transactionID *roomserverAPI.TransactionID
+		if txnID != nil {
+			transactionID = &roomserverAPI.TransactionID{
+				SessionID: device.SessionID, TransactionID: *txnID,
+			}
+		}
+
+		inputs = append(inputs, roomserverAPI.InputRoomEvent{
+			Kind:   roomserverAPI.KindNew,
+			Event:  &types.HeaderedEvent{PDU: pdu},
+			Origin: userID.Domain(),
+			// TODO: cryptoIDs - what to do with this field?
+			// should probably generate this based on the event type being sent?
+			//SendAsServer: roomserverAPI.DoNotSendToOtherServers,
+			TransactionID: transactionID,
+		})
+	}
+
+	startedSubmittingEvents := time.Now()
+	// send the events to the roomserver
+	if err := roomserverAPI.SendInputRoomEvents(req.Context(), rsAPI, userID.Domain(), inputs, false); err != nil {
+		util.GetLogger(req.Context()).WithError(err).Error("roomserverAPI.SendInputRoomEvents failed")
+		return util.JSONResponse{
+			Code: http.StatusInternalServerError,
+			JSON: spec.InternalServerError{Err: err.Error()},
+		}
+	}
+	timeToSubmitEvents := time.Since(startedSubmittingEvents)
+	sendEventDuration.With(prometheus.Labels{"action": "submit"}).Observe(float64(timeToSubmitEvents.Milliseconds()))
+
+	// Add response to transactionsCache
+	if txnID != nil {
+		// TODO : cryptoIDs - fix this
+		//res := util.JSONResponse{
+		//	Code: http.StatusOK,
+		//	JSON: sendEventResponse{e.EventID()},
+		//}
+		//txnCache.AddTransaction(device.AccessToken, *txnID, req.URL, &res)
+	}
+
+	return util.JSONResponse{
+		Code: http.StatusOK,
+	}
+}

clientapi/routing/sendevent.go

@@ -32,6 +32,7 @@ import (
 	"github.com/matrix-org/dendrite/syncapi/synctypes"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/gomatrixserverlib/fclient"
 	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 	"github.com/prometheus/client_golang/prometheus"
@@ -44,6 +45,11 @@ type sendEventResponse struct {
 	EventID string `json:"event_id"`
 }
 
+type sendEventResponseCryptoIDs struct {
+	EventID string          `json:"event_id"`
+	PDU     json.RawMessage `json:"pdu"`
+}
+
 var (
 	userRoomSendMutexes sync.Map // (roomID+userID) -> mutex. mutexes to ensure correct ordering of sendEvents
 )
@@ -94,7 +100,7 @@ func SendEvent(
 	}
 
 	// Translate user ID state keys to room keys in pseudo ID rooms
-	if roomVersion == gomatrixserverlib.RoomVersionPseudoIDs && stateKey != nil {
+	if (roomVersion == gomatrixserverlib.RoomVersionPseudoIDs || roomVersion == gomatrixserverlib.RoomVersionCryptoIDs) && stateKey != nil {
 		parsedRoomID, innerErr := spec.NewRoomID(roomID)
 		if innerErr != nil {
 			return util.JSONResponse{
@@ -148,7 +154,7 @@ func SendEvent(
 	}
 
 	// for power level events we need to replace the userID with the pseudoID
-	if roomVersion == gomatrixserverlib.RoomVersionPseudoIDs && eventType == spec.MRoomPowerLevels {
+	if (roomVersion == gomatrixserverlib.RoomVersionPseudoIDs || roomVersion == gomatrixserverlib.RoomVersionCryptoIDs) && eventType == spec.MRoomPowerLevels {
 		err = updatePowerLevels(req, r, roomID, rsAPI)
 		if err != nil {
 			return util.JSONResponse{
@@ -166,7 +172,7 @@ func SendEvent(
 		}
 	}
 
-	e, resErr := generateSendEvent(req.Context(), r, device, roomID, eventType, stateKey, rsAPI, evTime)
+	e, resErr := generateSendEvent(req.Context(), r, device, roomID, eventType, stateKey, rsAPI, evTime, false)
 	if resErr != nil {
 		return *resErr
 	}
@@ -262,6 +268,156 @@ func SendEvent(
 	return res
 }
 
+// SendEventCryptoIDs implements:
+//
+//	/rooms/{roomID}/send/{eventType}
+//	/rooms/{roomID}/send/{eventType}/{txnID}
+//	/rooms/{roomID}/state/{eventType}/{stateKey}
+//
+// nolint: gocyclo
+func SendEventCryptoIDs(
+	req *http.Request,
+	device *userapi.Device,
+	roomID, eventType string, txnID, stateKey *string,
+	cfg *config.ClientAPI,
+	rsAPI api.ClientRoomserverAPI,
+	txnCache *transactions.Cache,
+) util.JSONResponse {
+	roomVersion, err := rsAPI.QueryRoomVersionForRoom(req.Context(), roomID)
+	if err != nil {
+		return util.JSONResponse{
+			Code: http.StatusBadRequest,
+			JSON: spec.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
+		}
+	}
+
+	// Translate user ID state keys to room keys in pseudo ID rooms
+	if (roomVersion == gomatrixserverlib.RoomVersionPseudoIDs || roomVersion == gomatrixserverlib.RoomVersionCryptoIDs) && stateKey != nil {
+		parsedRoomID, innerErr := spec.NewRoomID(roomID)
+		if innerErr != nil {
+			return util.JSONResponse{
+				Code: http.StatusBadRequest,
+				JSON: spec.InvalidParam("invalid room ID"),
+			}
+		}
+
+		newStateKey, innerErr := synctypes.FromClientStateKey(*parsedRoomID, *stateKey, func(roomID spec.RoomID, userID spec.UserID) (*spec.SenderID, error) {
+			return rsAPI.QuerySenderIDForUser(req.Context(), roomID, userID)
+		})
+		if innerErr != nil {
+			// TODO: work out better logic for failure cases (e.g. sender ID not found)
+			util.GetLogger(req.Context()).WithError(innerErr).Error("synctypes.FromClientStateKey failed")
+			return util.JSONResponse{
+				Code: http.StatusInternalServerError,
+				JSON: spec.Unknown("internal server error"),
+			}
+		}
+		stateKey = newStateKey
+	}
+
+	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 == spec.MRoomMember {
+		delete(r, "join_authorised_via_users_server")
+	}
+
+	// for power level events we need to replace the userID with the pseudoID
+	if (roomVersion == gomatrixserverlib.RoomVersionPseudoIDs || roomVersion == gomatrixserverlib.RoomVersionCryptoIDs) && eventType == spec.MRoomPowerLevels {
+		err = updatePowerLevels(req, r, roomID, rsAPI)
+		if err != nil {
+			return util.JSONResponse{
+				Code: http.StatusInternalServerError,
+				JSON: spec.InternalServerError{Err: err.Error()},
+			}
+		}
+	}
+
+	evTime, err := httputil.ParseTSParam(req)
+	if err != nil {
+		return util.JSONResponse{
+			Code: http.StatusBadRequest,
+			JSON: spec.InvalidParam(err.Error()),
+		}
+	}
+
+	e, resErr := generateSendEvent(req.Context(), r, device, roomID, eventType, stateKey, rsAPI, evTime, true)
+	if resErr != nil {
+		return *resErr
+	}
+	timeToGenerateEvent := time.Since(startedGeneratingEvent)
+
+	// validate that the aliases exists
+	if eventType == spec.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: spec.InvalidParam("Request contains invalid aliases."),
+			}
+		}
+		aliasRes := &api.GetAliasesForRoomIDResponse{}
+		if err = rsAPI.GetAliasesForRoomID(req.Context(), &api.GetAliasesForRoomIDRequest{RoomID: roomID}, aliasRes); err != nil {
+			return util.JSONResponse{
+				Code: http.StatusInternalServerError,
+				JSON: spec.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: spec.BadAlias("No matching alias found."),
+			}
+		}
+	}
+	sendEventDuration.With(prometheus.Labels{"action": "build"}).Observe(float64(timeToGenerateEvent.Milliseconds()))
+
+	res := util.JSONResponse{
+		Code: http.StatusOK,
+		JSON: sendEventResponseCryptoIDs{
+			EventID: e.EventID(),
+			PDU:     json.RawMessage(e.JSON()),
+		},
+	}
+
+	return res
+}
+
 func updatePowerLevels(req *http.Request, r map[string]interface{}, roomID string, rsAPI api.ClientRoomserverAPI) error {
 	users, ok := r["users"]
 	if !ok {
@@ -329,6 +485,7 @@ func generateSendEvent(
 	roomID, eventType string, stateKey *string,
 	rsAPI api.ClientRoomserverAPI,
 	evTime time.Time,
+	cryptoIDs bool,
 ) (gomatrixserverlib.PDU, *util.JSONResponse) {
 	// parse the incoming http request
 	fullUserID, err := spec.NewUserID(device.UserID, true)
@@ -376,13 +533,19 @@ func generateSendEvent(
 		}
 	}
 
-	identity, err := rsAPI.SigningIdentityFor(ctx, *validRoomID, *fullUserID)
-	if err != nil {
+	var identity fclient.SigningIdentity
+	if !cryptoIDs {
+		id, idErr := rsAPI.SigningIdentityFor(ctx, *validRoomID, *fullUserID)
+		if idErr != nil {
 			return nil, &util.JSONResponse{
 				Code: http.StatusInternalServerError,
 				JSON: spec.InternalServerError{},
 			}
 		}
+		identity = id
+	} else {
+		identity.ServerName = spec.ServerName(*senderID)
+	}
 
 	var queryRes api.QueryLatestEventsAndStateResponse
 	e, err := eventutil.QueryAndBuildEvent(ctx, &proto, &identity, evTime, rsAPI, &queryRes)

clientapi/routing/server_notices.go

@@ -169,7 +169,7 @@ func SendServerNotice(
 			PowerLevelContentOverride: pl,
 		}
 
-		roomRes := createRoom(ctx, crReq, senderDevice, cfgClient, userAPI, rsAPI, asAPI, time.Now())
+		roomRes := createRoom(ctx, crReq, senderDevice, cfgClient, userAPI, rsAPI, asAPI, time.Now(), false)
 
 		switch data := roomRes.JSON.(type) {
 		case createRoomResponse:
@@ -215,7 +215,7 @@ func SendServerNotice(
 		}
 		if !membershipRes.IsInRoom {
 			// re-invite the user
-			res, err := sendInvite(ctx, userAPI, senderDevice, roomID, r.UserID, "Server notice room", cfgClient, rsAPI, asAPI, time.Now())
+			res, err := sendInvite(ctx, userAPI, senderDevice, roomID, r.UserID, "Server notice room", cfgClient, rsAPI, asAPI, time.Now(), false)
 			if err != nil {
 				return res
 			}
@@ -228,7 +228,7 @@ func SendServerNotice(
 		"body":    r.Content.Body,
 		"msgtype": r.Content.MsgType,
 	}
-	e, resErr := generateSendEvent(ctx, request, senderDevice, roomID, "m.room.message", nil, rsAPI, time.Now())
+	e, resErr := generateSendEvent(ctx, request, senderDevice, roomID, "m.room.message", nil, rsAPI, time.Now(), false)
 	if resErr != nil {
 		logrus.Errorf("failed to send message: %+v", resErr)
 		return *resErr

clientapi/routing/state.go

@@ -198,6 +198,7 @@ func OnIncomingStateRequest(ctx context.Context, device *userapi.Device, rsAPI a
 // state to see if there is an event with that type and state key, if there
 // is then (by default) we return the content, otherwise a 404.
 // If eventFormat=true, sends the whole event else just the content.
+// nolint:gocyclo
 func OnIncomingStateTypeRequest(
 	ctx context.Context, device *userapi.Device, rsAPI api.ClientRoomserverAPI,
 	roomID, evType, stateKey string, eventFormat bool,
@@ -214,7 +215,7 @@ func OnIncomingStateTypeRequest(
 	}
 
 	// Translate user ID state keys to room keys in pseudo ID rooms
-	if roomVer == gomatrixserverlib.RoomVersionPseudoIDs {
+	if roomVer == gomatrixserverlib.RoomVersionPseudoIDs || roomVer == gomatrixserverlib.RoomVersionCryptoIDs {
 		parsedRoomID, err := spec.NewRoomID(roomID)
 		if err != nil {
 			return util.JSONResponse{

federationapi/api/api.go

@@ -58,12 +58,18 @@ type RoomserverFederationAPI interface {
 	PerformDirectoryLookup(ctx context.Context, request *PerformDirectoryLookupRequest, response *PerformDirectoryLookupResponse) error
 	// Handle an instruction to make_join & send_join with a remote server.
 	PerformJoin(ctx context.Context, request *PerformJoinRequest, response *PerformJoinResponse)
+	PerformMakeJoin(ctx context.Context, request *PerformJoinRequest) (gomatrixserverlib.PDU, gomatrixserverlib.RoomVersion, spec.ServerName, error)
+	PerformSendJoin(ctx context.Context, request *PerformSendJoinRequestCryptoIDs, response *PerformJoinResponse)
 	// Handle an instruction to make_leave & send_leave with a remote server.
-	PerformLeave(ctx context.Context, request *PerformLeaveRequest, response *PerformLeaveResponse) error
+	PerformLeave(ctx context.Context, request *PerformLeaveRequest, response *PerformLeaveResponse, cryptoIDs bool) error
 	// Handle sending an invite to a remote server.
 	SendInvite(ctx context.Context, event gomatrixserverlib.PDU, strippedState []gomatrixserverlib.InviteStrippedState) (gomatrixserverlib.PDU, error)
 	// Handle sending an invite to a remote server.
 	SendInviteV3(ctx context.Context, event gomatrixserverlib.ProtoEvent, invitee spec.UserID, version gomatrixserverlib.RoomVersion, strippedState []gomatrixserverlib.InviteStrippedState) (gomatrixserverlib.PDU, error)
+	// Handle sending an invite to a remote server.
+	MakeInviteCryptoIDs(ctx context.Context, event gomatrixserverlib.ProtoEvent, invitee spec.UserID, version gomatrixserverlib.RoomVersion, strippedState []gomatrixserverlib.InviteStrippedState) (gomatrixserverlib.PDU, error)
+	// Handle sending an invite to a remote server.
+	SendInviteCryptoIDs(ctx context.Context, event gomatrixserverlib.PDU, invitee spec.UserID, version gomatrixserverlib.RoomVersion) error
 	// Handle an instruction to peek a room on a remote server.
 	PerformOutboundPeek(ctx context.Context, request *PerformOutboundPeekRequest, response *PerformOutboundPeekResponse) error
 	// Query the server names of the joined hosts in a room.
@@ -168,6 +174,15 @@ type PerformJoinRequest struct {
 	Unsigned    map[string]interface{} `json:"unsigned"`
 }
 
+type PerformSendJoinRequestCryptoIDs struct {
+	RoomID string `json:"room_id"`
+	UserID string `json:"user_id"`
+	// The sorted list of servers to try. Servers will be tried sequentially, after de-duplication.
+	ServerNames types.ServerNames      `json:"server_names"`
+	Unsigned    map[string]interface{} `json:"unsigned"`
+	Event       gomatrixserverlib.PDU
+}
+
 type PerformJoinResponse struct {
 	JoinedVia spec.ServerName
 	LastError *gomatrix.HTTPError

federationapi/internal/perform.go

@@ -239,6 +239,319 @@ func (r *FederationInternalAPI) performJoinUsingServer(
 	return nil
 }
 
+// PerformMakeJoin implements api.FederationInternalAPI
+func (r *FederationInternalAPI) PerformMakeJoin(
+	ctx context.Context,
+	request *api.PerformJoinRequest,
+) (gomatrixserverlib.PDU, gomatrixserverlib.RoomVersion, spec.ServerName, error) {
+	// Check that a join isn't already in progress for this user/room.
+	j := federatedJoin{request.UserID, request.RoomID}
+	if _, found := r.joins.Load(j); found {
+		return nil, "", "", &gomatrix.HTTPError{
+			Code: 429,
+			Message: `{
+				"errcode": "M_LIMIT_EXCEEDED",
+				"error": "There is already a federated join to this room in progress. Please wait for it to finish."
+			}`, // TODO: Why do none of our error types play nicely with each other?
+		}
+	}
+	r.joins.Store(j, nil)
+	defer r.joins.Delete(j)
+
+	// Deduplicate the server names we were provided but keep the ordering
+	// as this encodes useful information about which servers are most likely
+	// to respond.
+	seenSet := make(map[spec.ServerName]bool)
+	var uniqueList []spec.ServerName
+	for _, srv := range request.ServerNames {
+		if seenSet[srv] || r.cfg.Matrix.IsLocalServerName(srv) {
+			continue
+		}
+		seenSet[srv] = true
+		uniqueList = append(uniqueList, srv)
+	}
+	request.ServerNames = uniqueList
+
+	// Try each server that we were provided until we land on one that
+	// successfully completes the make-join send-join dance.
+	var lastErr error
+	for _, serverName := range request.ServerNames {
+		var joinEvent gomatrixserverlib.PDU
+		var roomVersion gomatrixserverlib.RoomVersion
+		var err error
+		if joinEvent, roomVersion, _, err = r.performMakeJoinUsingServer(
+			ctx,
+			request.RoomID,
+			request.UserID,
+			request.Content,
+			serverName,
+		); err != nil {
+			logrus.WithError(err).WithFields(logrus.Fields{
+				"server_name": serverName,
+				"room_id":     request.RoomID,
+			}).Warnf("Failed to join room through server")
+			lastErr = err
+			continue
+		}
+
+		// We're all good.
+		return joinEvent, roomVersion, serverName, err
+	}
+
+	// If we reach here then we didn't complete a join for some reason.
+	var httpErr gomatrix.HTTPError
+	var lastError *gomatrix.HTTPError
+	if ok := errors.As(lastErr, &httpErr); ok {
+		httpErr.Message = string(httpErr.Contents)
+		lastError = &httpErr
+	} else {
+		lastError = &gomatrix.HTTPError{
+			Code:         0,
+			WrappedError: nil,
+			Message:      "Unknown HTTP error",
+		}
+		if lastErr != nil {
+			lastError.Message = lastErr.Error()
+		}
+	}
+
+	logrus.Errorf(
+		"failed to join user %q to room %q through %d server(s): last error %s",
+		request.UserID, request.RoomID, len(request.ServerNames), lastError,
+	)
+	return nil, "", "", lastError
+}
+
+func (r *FederationInternalAPI) performMakeJoinUsingServer(
+	ctx context.Context,
+	roomID, userID string,
+	content map[string]interface{},
+	serverName spec.ServerName,
+) (gomatrixserverlib.PDU, gomatrixserverlib.RoomVersion, spec.SenderID, error) {
+	if !r.shouldAttemptDirectFederation(serverName) {
+		return nil, "", "", fmt.Errorf("relay servers have no meaningful response for join.")
+	}
+
+	user, err := spec.NewUserID(userID, true)
+	if err != nil {
+		return nil, "", "", err
+	}
+	room, err := spec.NewRoomID(roomID)
+	if err != nil {
+		return nil, "", "", err
+	}
+
+	joinInput := gomatrixserverlib.PerformMakeJoinInput{
+		UserID:     user,
+		RoomID:     room,
+		ServerName: serverName,
+		Content:    content,
+		PrivateKey: r.cfg.Matrix.PrivateKey,
+		KeyID:      r.cfg.Matrix.KeyID,
+		KeyRing:    r.keyRing,
+		GetOrCreateSenderID: func(ctx context.Context, userID spec.UserID, roomID spec.RoomID, roomVersion string) (spec.SenderID, ed25519.PrivateKey, error) {
+			// assign a roomNID, otherwise we can't create a private key for the user
+			_, nidErr := r.rsAPI.AssignRoomNID(ctx, roomID, gomatrixserverlib.RoomVersion(roomVersion))
+			if nidErr != nil {
+				return "", nil, nidErr
+			}
+			key, keyErr := r.rsAPI.GetOrCreateUserRoomPrivateKey(ctx, userID, roomID)
+			if keyErr != nil {
+				return "", nil, keyErr
+			}
+			return spec.SenderIDFromPseudoIDKey(key), key, nil
+		},
+	}
+	joinEvent, version, senderID, joinErr := gomatrixserverlib.PerformMakeJoin(ctx, r, joinInput)
+
+	if joinErr != nil {
+		if !joinErr.Reachable {
+			r.statistics.ForServer(joinErr.ServerName).Failure()
+		} else {
+			r.statistics.ForServer(joinErr.ServerName).Success(statistics.SendDirect)
+		}
+		return nil, "", "", joinErr.Err
+	}
+	r.statistics.ForServer(serverName).Success(statistics.SendDirect)
+	if joinEvent == nil {
+		return nil, "", "", fmt.Errorf("Received nil joinEvent response from gomatrixserverlib.PerformJoin")
+	}
+
+	return joinEvent, version, senderID, nil
+}
+
+// PerformSendJoin implements api.FederationInternalAPI
+func (r *FederationInternalAPI) PerformSendJoin(
+	ctx context.Context,
+	request *api.PerformSendJoinRequestCryptoIDs,
+	response *api.PerformJoinResponse,
+) {
+	// Check that a join isn't already in progress for this user/room.
+	j := federatedJoin{request.UserID, request.RoomID}
+	if _, found := r.joins.Load(j); found {
+		response.LastError = &gomatrix.HTTPError{
+			Code: 429,
+			Message: `{
+				"errcode": "M_LIMIT_EXCEEDED",
+				"error": "There is already a federated join to this room in progress. Please wait for it to finish."
+			}`,
+		}
+		return
+	}
+	r.joins.Store(j, nil)
+	defer r.joins.Delete(j)
+
+	// Deduplicate the server names we were provided but keep the ordering
+	// as this encodes useful information about which servers are most likely
+	// to respond.
+	seenSet := make(map[spec.ServerName]bool)
+	var uniqueList []spec.ServerName
+	for _, srv := range request.ServerNames {
+		if seenSet[srv] || r.cfg.Matrix.IsLocalServerName(srv) {
+			continue
+		}
+		seenSet[srv] = true
+		uniqueList = append(uniqueList, srv)
+	}
+	request.ServerNames = uniqueList
+
+	// Try each server that we were provided until we land on one that
+	// successfully completes the make-join send-join dance.
+	var lastErr error
+	for _, serverName := range request.ServerNames {
+		if err := r.performSendJoinUsingServer(
+			ctx,
+			request.RoomID,
+			request.UserID,
+			request.Unsigned,
+			request.Event,
+			serverName,
+		); err != nil {
+			logrus.WithError(err).WithFields(logrus.Fields{
+				"server_name": serverName,
+				"room_id":     request.RoomID,
+			}).Warnf("Failed to join room through server")
+			lastErr = err
+			continue
+		}
+
+		// We're all good.
+		return
+	}
+
+	// If we reach here then we didn't complete a join for some reason.
+	var httpErr gomatrix.HTTPError
+	var lastError *gomatrix.HTTPError
+	if ok := errors.As(lastErr, &httpErr); ok {
+		httpErr.Message = string(httpErr.Contents)
+		lastError = &httpErr
+	} else {
+		lastError = &gomatrix.HTTPError{
+			Code:         0,
+			WrappedError: nil,
+			Message:      "Unknown HTTP error",
+		}
+		if lastErr != nil {
+			lastError.Message = lastErr.Error()
+		}
+	}
+
+	logrus.Errorf(
+		"failed to join user %q to room %q through %d server(s): last error %s",
+		request.UserID, request.RoomID, len(request.ServerNames), lastError,
+	)
+}
+
+func (r *FederationInternalAPI) performSendJoinUsingServer(
+	ctx context.Context,
+	roomID, userID string,
+	unsigned map[string]interface{},
+	event gomatrixserverlib.PDU,
+	serverName spec.ServerName,
+) error {
+	user, err := spec.NewUserID(userID, true)
+	if err != nil {
+		return err
+	}
+	room, err := spec.NewRoomID(roomID)
+	if err != nil {
+		return err
+	}
+	senderID, err := r.rsAPI.QuerySenderIDForUser(ctx, *room, *user)
+	if err != nil {
+		return err
+	}
+
+	joinInput := gomatrixserverlib.PerformSendJoinInput{
+		RoomID:      room,
+		ServerName:  serverName,
+		Unsigned:    unsigned,
+		Origin:      user.Domain(),
+		SenderID:    *senderID,
+		KeyRing:     r.keyRing,
+		Event:       event,
+		RoomVersion: event.Version(),
+		EventProvider: federatedEventProvider(ctx, r.federation, r.keyRing, user.Domain(), serverName, func(roomID spec.RoomID, senderID spec.SenderID) (*spec.UserID, error) {
+			return r.rsAPI.QueryUserIDForSender(ctx, roomID, senderID)
+		}),
+		UserIDQuerier: func(roomID spec.RoomID, senderID spec.SenderID) (*spec.UserID, error) {
+			return r.rsAPI.QueryUserIDForSender(ctx, roomID, senderID)
+		},
+		StoreSenderIDFromPublicID: func(ctx context.Context, senderID spec.SenderID, userIDRaw string, roomID spec.RoomID) error {
+			storeUserID, userErr := spec.NewUserID(userIDRaw, true)
+			if userErr != nil {
+				return userErr
+			}
+			return r.rsAPI.StoreUserRoomPublicKey(ctx, senderID, *storeUserID, roomID)
+		},
+	}
+	response, joinErr := gomatrixserverlib.PerformSendJoin(ctx, r, joinInput)
+	if joinErr != nil {
+		if !joinErr.Reachable {
+			r.statistics.ForServer(joinErr.ServerName).Failure()
+		} else {
+			r.statistics.ForServer(joinErr.ServerName).Success(statistics.SendDirect)
+		}
+		return joinErr.Err
+	}
+	r.statistics.ForServer(serverName).Success(statistics.SendDirect)
+	if response == nil {
+		return fmt.Errorf("Received nil response from gomatrixserverlib.PerformSendJoin")
+	}
+
+	// We need to immediately update our list of joined hosts for this room now as we are technically
+	// joined. We must do this synchronously: we cannot rely on the roomserver output events as they
+	// will happen asyncly. If we don't update this table, you can end up with bad failure modes like
+	// joining a room, waiting for 200 OK then changing device keys and have those keys not be sent
+	// to other servers (this was a cause of a flakey sytest "Local device key changes get to remote servers")
+	// The events are trusted now as we performed auth checks above.
+	joinedHosts, err := consumers.JoinedHostsFromEvents(ctx, response.StateSnapshot.GetStateEvents().TrustedEvents(response.JoinEvent.Version(), false), r.rsAPI)
+	if err != nil {
+		return fmt.Errorf("JoinedHostsFromEvents: failed to get joined hosts: %s", err)
+	}
+
+	logrus.WithField("room", roomID).Infof("Joined federated room with %d hosts", len(joinedHosts))
+	if _, err = r.db.UpdateRoom(context.Background(), roomID, joinedHosts, nil, true); err != nil {
+		return fmt.Errorf("UpdatedRoom: failed to update room with joined hosts: %s", err)
+	}
+
+	// TODO: Can I change this to not take respState but instead just take an opaque list of events?
+	if err = roomserverAPI.SendEventWithState(
+		context.Background(),
+		r.rsAPI,
+		user.Domain(),
+		roomserverAPI.KindNew,
+		response.StateSnapshot,
+		&types.HeaderedEvent{PDU: response.JoinEvent},
+		serverName,
+		nil,
+		false,
+	); err != nil {
+		return fmt.Errorf("roomserverAPI.SendEventWithState: %w", err)
+	}
+	return nil
+}
+
 // PerformOutboundPeekRequest implements api.FederationInternalAPI
 func (r *FederationInternalAPI) PerformOutboundPeek(
 	ctx context.Context,
@@ -433,6 +746,7 @@ func (r *FederationInternalAPI) PerformLeave(
 	ctx context.Context,
 	request *api.PerformLeaveRequest,
 	response *api.PerformLeaveResponse,
+	cryptoIDs bool,
 ) (err error) {
 	userID, err := spec.NewUserID(request.UserID, true)
 	if err != nil {
@@ -649,6 +963,87 @@ func (r *FederationInternalAPI) SendInviteV3(
 	return inviteEvent, nil
 }
 
+// MakeInviteCryptoIDs implements api.FederationInternalAPI
+func (r *FederationInternalAPI) MakeInviteCryptoIDs(ctx context.Context, event gomatrixserverlib.ProtoEvent, invitee spec.UserID, version gomatrixserverlib.RoomVersion, strippedState []gomatrixserverlib.InviteStrippedState) (gomatrixserverlib.PDU, error) {
+	validRoomID, err := spec.NewRoomID(event.RoomID)
+	if err != nil {
+		return nil, err
+	}
+	verImpl, err := gomatrixserverlib.GetRoomVersion(version)
+	if err != nil {
+		return nil, err
+	}
+
+	inviter, err := r.rsAPI.QueryUserIDForSender(ctx, *validRoomID, spec.SenderID(event.SenderID))
+	if err != nil {
+		return nil, err
+	}
+
+	// TODO (devon): This should be allowed via a relay. Currently only transactions
+	// can be sent to relays. Would need to extend relays to handle invites.
+	if !r.shouldAttemptDirectFederation(invitee.Domain()) {
+		return nil, fmt.Errorf("relay servers have no meaningful response for invite.")
+	}
+
+	logrus.WithFields(logrus.Fields{
+		"user_id":      invitee.String(),
+		"room_id":      event.RoomID,
+		"room_version": version,
+		"destination":  invitee.Domain(),
+	}).Info("Sending /send_invite")
+
+	inviteReq, err := fclient.NewInviteV3Request(event, version, strippedState)
+	if err != nil {
+		return nil, fmt.Errorf("gomatrixserverlib.NewInviteV3Request: %w", err)
+	}
+
+	inviteRes, err := r.federation.MakeInviteCryptoIDs(ctx, inviter.Domain(), invitee.Domain(), inviteReq, invitee)
+	if err != nil {
+		return nil, fmt.Errorf("r.federation.SendInviteCryptoIDs: failed to send invite: %w", err)
+	}
+
+	inviteEvent, err := verImpl.NewEventFromUntrustedJSON(inviteRes.Event)
+	if err != nil {
+		return nil, fmt.Errorf("r.federation.SendInviteCryptoIDs failed to decode event response: %w", err)
+	}
+	return inviteEvent, nil
+}
+
+// SendInviteCryptoIDs implements api.FederationInternalAPI
+func (r *FederationInternalAPI) SendInviteCryptoIDs(ctx context.Context, event gomatrixserverlib.PDU, invitee spec.UserID, version gomatrixserverlib.RoomVersion) error {
+	validRoomID := event.RoomID()
+
+	inviter, err := r.rsAPI.QueryUserIDForSender(ctx, validRoomID, event.SenderID())
+	if err != nil {
+		return err
+	}
+
+	// TODO (devon): This should be allowed via a relay. Currently only transactions
+	// can be sent to relays. Would need to extend relays to handle invites.
+	if !r.shouldAttemptDirectFederation(invitee.Domain()) {
+		return fmt.Errorf("relay servers have no meaningful response for invite.")
+	}
+
+	logrus.WithFields(logrus.Fields{
+		"user_id":      invitee.String(),
+		"room_id":      event.RoomID,
+		"room_version": version,
+		"destination":  invitee.Domain(),
+	}).Info("Sending /make_invite")
+
+	inviteReq, err := fclient.NewSendInviteCryptoIDsRequest(event, version)
+	if err != nil {
+		return fmt.Errorf("gomatrixserverlib.NewInviteV3Request: %w", err)
+	}
+
+	err = r.federation.SendInviteCryptoIDs(ctx, inviter.Domain(), invitee.Domain(), inviteReq, invitee)
+	if err != nil {
+		return fmt.Errorf("r.federation.SendInviteCryptoIDs: failed to send invite: %w", err)
+	}
+
+	return nil
+}
+
 // PerformServersAlive implements api.FederationInternalAPI
 func (r *FederationInternalAPI) PerformBroadcastEDU(
 	ctx context.Context,

go.mod

@@ -1,5 +1,9 @@
 module github.com/matrix-org/dendrite
 
+//replace github.com/matrix-org/gomatrixserverlib => ../../gomatrixserverlib/crypto-ids/
+
+//replace github.com/matrix-org/gomatrixserverlib => /src/gmsl/
+
 require (
 	github.com/Arceliar/ironwood v0.0.0-20221025225125-45b4281814c2
 	github.com/Arceliar/phony v0.0.0-20210209235338-dde1a8dca979
@@ -22,7 +26,7 @@ require (
 	github.com/matrix-org/dugong v0.0.0-20210921133753-66e6b1c67e2e
 	github.com/matrix-org/go-sqlite3-js v0.0.0-20220419092513-28aa791a1c91
 	github.com/matrix-org/gomatrix v0.0.0-20220926102614-ceba4d9f7530
-	github.com/matrix-org/gomatrixserverlib v0.0.0-20230926165653-79fcff283fc4
+	github.com/matrix-org/gomatrixserverlib v0.0.0-20231219232834-bbfb4a048862
 	github.com/matrix-org/pinecone v0.11.1-0.20230810010612-ea4c33717fd7
 	github.com/matrix-org/util v0.0.0-20221111132719-399730281e66
 	github.com/mattn/go-sqlite3 v1.14.17
@@ -42,12 +46,12 @@ require (
 	github.com/uber/jaeger-lib v2.4.1+incompatible
 	github.com/yggdrasil-network/yggdrasil-go v0.4.6
 	go.uber.org/atomic v1.10.0
-	golang.org/x/crypto v0.13.0
+	golang.org/x/crypto v0.17.0
 	golang.org/x/exp v0.0.0-20230809150735-7b3493d9a819
 	golang.org/x/image v0.5.0
 	golang.org/x/mobile v0.0.0-20221020085226-b36e6246172e
 	golang.org/x/sync v0.3.0
-	golang.org/x/term v0.12.0
+	golang.org/x/term v0.15.0
 	gopkg.in/h2non/bimg.v1 v1.1.9
 	gopkg.in/yaml.v2 v2.4.0
 	gotest.tools/v3 v3.4.0
@@ -124,8 +128,8 @@ require (
 	go.etcd.io/bbolt v1.3.6 // indirect
 	golang.org/x/mod v0.12.0 // indirect
 	golang.org/x/net v0.14.0 // indirect
-	golang.org/x/sys v0.12.0 // indirect
-	golang.org/x/text v0.13.0 // indirect
+	golang.org/x/sys v0.15.0 // indirect
+	golang.org/x/text v0.14.0 // indirect
 	golang.org/x/time v0.3.0 // indirect
 	golang.org/x/tools v0.12.0 // indirect
 	google.golang.org/protobuf v1.30.0 // indirect

go.sum

@@ -208,8 +208,8 @@ github.com/matrix-org/go-sqlite3-js v0.0.0-20220419092513-28aa791a1c91 h1:s7fexw
 github.com/matrix-org/go-sqlite3-js v0.0.0-20220419092513-28aa791a1c91/go.mod h1:e+cg2q7C7yE5QnAXgzo512tgFh1RbQLC0+jozuegKgo=
 github.com/matrix-org/gomatrix v0.0.0-20220926102614-ceba4d9f7530 h1:kHKxCOLcHH8r4Fzarl4+Y3K5hjothkVW5z7T1dUM11U=
 github.com/matrix-org/gomatrix v0.0.0-20220926102614-ceba4d9f7530/go.mod h1:/gBX06Kw0exX1HrwmoBibFA98yBk/jxKpGVeyQbff+s=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20230926165653-79fcff283fc4 h1:UuXfC7b29RBDfMdLmggeF3opu3XuGi8bNT9SKZtZc3I=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20230926165653-79fcff283fc4/go.mod h1:H9V9N3Uqn1bBJqYJNGK1noqtgJTaCEhtTdcH/mp50uU=
+github.com/matrix-org/gomatrixserverlib v0.0.0-20231219232834-bbfb4a048862 h1:Kuya3qas85ZvVVkuOpemwhgvdJbLojvwvt3xyJTp1dY=
+github.com/matrix-org/gomatrixserverlib v0.0.0-20231219232834-bbfb4a048862/go.mod h1:H9V9N3Uqn1bBJqYJNGK1noqtgJTaCEhtTdcH/mp50uU=
 github.com/matrix-org/pinecone v0.11.1-0.20230810010612-ea4c33717fd7 h1:6t8kJr8i1/1I5nNttw6nn1ryQJgzVlBmSGgPiiaTdw4=
 github.com/matrix-org/pinecone v0.11.1-0.20230810010612-ea4c33717fd7/go.mod h1:ReWMS/LoVnOiRAdq9sNUC2NZnd1mZkMNB52QhpTRWjg=
 github.com/matrix-org/util v0.0.0-20221111132719-399730281e66 h1:6z4KxomXSIGWqhHcfzExgkH3Z3UkIXry4ibJS4Aqz2Y=
@@ -354,8 +354,8 @@ golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8U
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20210421170649-83a5a9bb288b/go.mod h1:T9bdIzuCu7OtxOm1hfPfRQxPLYneinmdGuTeoZ9dtd4=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
-golang.org/x/crypto v0.13.0 h1:mvySKfSWJ+UKUii46M40LOvyWfN0s2U+46/jDd0e6Ck=
-golang.org/x/crypto v0.13.0/go.mod h1:y6Z2r+Rw4iayiXXAIxJIDAJ1zMW4yaTpebo8fPOliYc=
+golang.org/x/crypto v0.17.0 h1:r8bRNjWL3GshPW3gkd+RpvzWrZAwPS49OmTGZ/uhM4k=
+golang.org/x/crypto v0.17.0/go.mod h1:gCAAfMLgwOJRpTjQ2zCCt2OcSfYMTeZVSRtQlPC7Nq4=
 golang.org/x/exp v0.0.0-20180321215751-8460e604b9de/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20180807140117-3d87b88a115f/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190125153040-c74c464bbbf2/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
@@ -418,19 +418,19 @@ golang.org/x/sys v0.0.0-20220715151400-c0bba94af5f8/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20221010170243-090e33056c14/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.12.0 h1:CM0HF96J0hcLAwsHPJZjfdNzs0gftsLfgKt57wWHJ0o=
-golang.org/x/sys v0.12.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.15.0 h1:h48lPFYpsTvQJZF4EKyI4aLHaev3CxivZmv7yZig9pc=
+golang.org/x/sys v0.15.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
-golang.org/x/term v0.12.0 h1:/ZfYdc3zq+q02Rv9vGqTeSItdzZTSNDmfTi0mBAuidU=
-golang.org/x/term v0.12.0/go.mod h1:owVbMEjm3cBLCHdkQu9b1opXd4ETQWc3BhuQGKgXgvU=
+golang.org/x/term v0.15.0 h1:y/Oo/a/q3IXu26lQgl04j/gjuBDOBlx7X6Om1j2CPW4=
+golang.org/x/term v0.15.0/go.mod h1:BDl952bC7+uMoWR75FIrCDx79TPU9oHkTZ9yRbYOrX0=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
 golang.org/x/text v0.7.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
-golang.org/x/text v0.13.0 h1:ablQoSUd0tRdKxZewP80B+BaqeKJuVhuRxj/dkrun3k=
-golang.org/x/text v0.13.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
+golang.org/x/text v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
+golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
 golang.org/x/time v0.0.0-20191024005414-555d28b269f0/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/time v0.3.0 h1:rg5rLMjNzMS1RkNLzCG38eapWhnYLFYXDXj2gOlr8j4=
 golang.org/x/time v0.3.0/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=

internal/eventutil/events.go

@@ -85,13 +85,21 @@ func BuildEvent(
 	}
 	builder := verImpl.NewEventBuilderFromProtoEvent(proto)
 
-	event, err := builder.Build(
+	var event gomatrixserverlib.PDU
+	if identity.PrivateKey != nil {
+		event, err = builder.Build(
 			evTime, identity.ServerName, identity.KeyID,
 			identity.PrivateKey,
 		)
 		if err != nil {
 			return nil, err
 		}
+	} else {
+		event, err = builder.BuildWithoutSigning(evTime, identity.ServerName)
+		if err != nil {
+			return nil, err
+		}
+	}
 
 	return &types.HeaderedEvent{PDU: event}, nil
 }

roomserver/api/api.go

@@ -92,6 +92,7 @@ type UserRoomPrivateKeyCreator interface {
 	// GetOrCreateUserRoomPrivateKey gets the user room key for the specified user. If no key exists yet, a new one is created.
 	GetOrCreateUserRoomPrivateKey(ctx context.Context, userID spec.UserID, roomID spec.RoomID) (ed25519.PrivateKey, error)
 	StoreUserRoomPublicKey(ctx context.Context, senderID spec.SenderID, userID spec.UserID, roomID spec.RoomID) error
+	ClaimOneTimeSenderIDForUser(ctx context.Context, roomID spec.RoomID, userID spec.UserID) (spec.SenderID, error)
 }
 
 type InputRoomEventsAPI interface {
@@ -222,6 +223,7 @@ type ClientRoomserverAPI interface {
 	DefaultRoomVersionAPI
 	QueryMembershipForUser(ctx context.Context, req *QueryMembershipForUserRequest, res *QueryMembershipForUserResponse) error
 	QueryMembershipsForRoom(ctx context.Context, req *QueryMembershipsForRoomRequest, res *QueryMembershipsForRoomResponse) error
+	InvitePending(ctx context.Context, roomID spec.RoomID, senderID spec.SenderID) (bool, error)
 	QueryRoomsForUser(ctx context.Context, userID spec.UserID, desiredMembership string) ([]spec.RoomID, error)
 	QueryStateAfterEvents(ctx context.Context, req *QueryStateAfterEventsRequest, res *QueryStateAfterEventsResponse) error
 	// QueryKnownUsers returns a list of users that we know about from our joined rooms.
@@ -232,6 +234,7 @@ type ClientRoomserverAPI interface {
 	GetRoomIDForAlias(ctx context.Context, req *GetRoomIDForAliasRequest, res *GetRoomIDForAliasResponse) error
 	GetAliasesForRoomID(ctx context.Context, req *GetAliasesForRoomIDRequest, res *GetAliasesForRoomIDResponse) error
 
+	PerformCreateRoomCryptoIDs(ctx context.Context, userID spec.UserID, roomID spec.RoomID, createRequest *PerformCreateRoomRequest) ([]gomatrixserverlib.PDU, error)
 	PerformCreateRoom(ctx context.Context, userID spec.UserID, roomID spec.RoomID, createRequest *PerformCreateRoomRequest) (string, *util.JSONResponse)
 	// PerformRoomUpgrade upgrades a room to a newer version
 	PerformRoomUpgrade(ctx context.Context, roomID string, userID spec.UserID, roomVersion gomatrixserverlib.RoomVersion) (newRoomID string, err error)
@@ -241,9 +244,12 @@ type ClientRoomserverAPI interface {
 	PerformAdminDownloadState(ctx context.Context, roomID, userID string, serverName spec.ServerName) error
 	PerformPeek(ctx context.Context, req *PerformPeekRequest) (roomID string, err error)
 	PerformUnpeek(ctx context.Context, roomID, userID, deviceID string) error
-	PerformInvite(ctx context.Context, req *PerformInviteRequest) error
+	PerformInvite(ctx context.Context, req *PerformInviteRequest, cryptoIDs bool) (gomatrixserverlib.PDU, error)
 	PerformJoin(ctx context.Context, req *PerformJoinRequest) (roomID string, joinedVia spec.ServerName, err error)
-	PerformLeave(ctx context.Context, req *PerformLeaveRequest, res *PerformLeaveResponse) error
+	PerformSendJoinCryptoIDs(ctx context.Context, req *PerformJoinRequestCryptoIDs) error
+	PerformSendInviteCryptoIDs(ctx context.Context, req *PerformInviteRequestCryptoIDs) error
+	PerformJoinCryptoIDs(ctx context.Context, req *PerformJoinRequest) (join gomatrixserverlib.PDU, roomID string, version gomatrixserverlib.RoomVersion, serverName spec.ServerName, err error)
+	PerformLeave(ctx context.Context, req *PerformLeaveRequest, res *PerformLeaveResponse, cryptoIDs bool) (gomatrixserverlib.PDU, error)
 	PerformPublish(ctx context.Context, req *PerformPublishRequest) error
 	// PerformForget forgets a rooms history for a specific user
 	PerformForget(ctx context.Context, req *PerformForgetRequest, resp *PerformForgetResponse) error
@@ -305,7 +311,7 @@ type FederationRoomserverAPI interface {
 	PerformInboundPeek(ctx context.Context, req *PerformInboundPeekRequest, res *PerformInboundPeekResponse) error
 	HandleInvite(ctx context.Context, event *types.HeaderedEvent) error
 
-	PerformInvite(ctx context.Context, req *PerformInviteRequest) error
+	PerformInvite(ctx context.Context, req *PerformInviteRequest, cryptoIDs bool) (gomatrixserverlib.PDU, error)
 	// Query a given amount (or less) of events prior to a given set of events.
 	PerformBackfill(ctx context.Context, req *PerformBackfillRequest, res *PerformBackfillResponse) error
 

roomserver/api/perform.go

@@ -29,6 +29,8 @@ type PerformCreateRoomRequest struct {
 	KeyID           gomatrixserverlib.KeyID
 	PrivateKey      ed25519.PrivateKey
 	EventTime       time.Time
+
+	SenderID string
 }
 
 type PerformJoinRequest struct {
@@ -38,6 +40,23 @@ type PerformJoinRequest struct {
 	Content       map[string]interface{} `json:"content"`
 	ServerNames   []spec.ServerName      `json:"server_names"`
 	Unsigned      map[string]interface{} `json:"unsigned"`
+	SenderID      spec.SenderID
+}
+
+type PerformJoinRequestCryptoIDs struct {
+	RoomID      string
+	UserID      string
+	IsGuest     bool
+	Content     map[string]interface{}
+	ServerNames []spec.ServerName
+	Unsigned    map[string]interface{}
+	JoinEvent   gomatrixserverlib.PDU
+}
+
+type PerformInviteRequestCryptoIDs struct {
+	RoomID      string
+	UserID      spec.UserID
+	InviteEvent gomatrixserverlib.PDU
 }
 
 type PerformLeaveRequest struct {

roomserver/internal/api.go

@@ -3,6 +3,7 @@ package internal
 import (
 	"context"
 	"crypto/ed25519"
+	"fmt"
 
 	"github.com/getsentry/sentry-go"
 	"github.com/matrix-org/gomatrixserverlib"
@@ -54,6 +55,7 @@ type RoomserverInternalAPI struct {
 	ServerACLs             *acls.ServerACLs
 	fsAPI                  fsAPI.RoomserverFederationAPI
 	asAPI                  asAPI.AppServiceInternalAPI
+	usAPI                  userapi.RoomserverUserAPI
 	NATSClient             *nats.Conn
 	JetStream              nats.JetStreamContext
 	Durable                string
@@ -214,6 +216,7 @@ func (r *RoomserverInternalAPI) SetFederationAPI(fsAPI fsAPI.RoomserverFederatio
 func (r *RoomserverInternalAPI) SetUserAPI(userAPI userapi.RoomserverUserAPI) {
 	r.Leaver.UserAPI = userAPI
 	r.Inputer.UserAPI = userAPI
+	r.usAPI = userAPI
 }
 
 func (r *RoomserverInternalAPI) SetAppserviceAPI(asAPI asAPI.AppServiceInternalAPI) {
@@ -251,24 +254,27 @@ func (r *RoomserverInternalAPI) PerformCreateRoom(
 func (r *RoomserverInternalAPI) PerformInvite(
 	ctx context.Context,
 	req *api.PerformInviteRequest,
-) error {
-	return r.Inviter.PerformInvite(ctx, req)
+	cryptoIDs bool,
+) (gomatrixserverlib.PDU, error) {
+	return r.Inviter.PerformInvite(ctx, req, cryptoIDs)
 }
 
 func (r *RoomserverInternalAPI) PerformLeave(
 	ctx context.Context,
 	req *api.PerformLeaveRequest,
 	res *api.PerformLeaveResponse,
-) error {
-	outputEvents, err := r.Leaver.PerformLeave(ctx, req, res)
+	cryptoIDs bool,
+) (gomatrixserverlib.PDU, error) {
+	outputEvents, leaveEvent, err := r.Leaver.PerformLeave(ctx, req, res, cryptoIDs)
 	if err != nil {
 		sentry.CaptureException(err)
-		return err
+		return nil, err
 	}
 	if len(outputEvents) == 0 {
-		return nil
+		return leaveEvent, nil
 	}
-	return r.OutputProducer.ProduceRoomEvents(req.RoomID, outputEvents)
+	// TODO: cryptoIDs - what to do with this?
+	return leaveEvent, r.OutputProducer.ProduceRoomEvents(req.RoomID, outputEvents)
 }
 
 func (r *RoomserverInternalAPI) PerformForget(
@@ -308,6 +314,10 @@ func (r *RoomserverInternalAPI) StoreUserRoomPublicKey(ctx context.Context, send
 	return err
 }
 
+func (r *RoomserverInternalAPI) ClaimOneTimeSenderIDForUser(ctx context.Context, roomID spec.RoomID, userID spec.UserID) (spec.SenderID, error) {
+	return r.usAPI.ClaimOneTimeCryptoID(ctx, roomID, userID)
+}
+
 func (r *RoomserverInternalAPI) SigningIdentityFor(ctx context.Context, roomID spec.RoomID, senderID spec.UserID) (fclient.SigningIdentity, error) {
 	roomVersion, ok := r.Cache.GetRoomVersion(roomID.String())
 	if !ok {
@@ -330,6 +340,19 @@ func (r *RoomserverInternalAPI) SigningIdentityFor(ctx context.Context, roomID s
 			ServerName: spec.ServerName(spec.SenderIDFromPseudoIDKey(privKey)),
 		}, nil
 	}
+	if roomVersion == gomatrixserverlib.RoomVersionCryptoIDs {
+		sender, err := r.QuerySenderIDForUser(ctx, roomID, senderID)
+		if err != nil {
+			return fclient.SigningIdentity{}, err
+		} else if sender == nil {
+			return fclient.SigningIdentity{}, fmt.Errorf("no sender ID for %s in %s", senderID.String(), roomID.String())
+		}
+		return fclient.SigningIdentity{
+			PrivateKey: nil,
+			KeyID:      "ed25519:1",
+			ServerName: spec.ServerName(*sender),
+		}, nil
+	}
 	identity, err := r.Cfg.Global.SigningIdentityFor(senderID.Domain())
 	if err != nil {
 		return fclient.SigningIdentity{}, err

roomserver/internal/input/input_events.go

@@ -445,7 +445,7 @@ func (r *Inputer) processRoomEvent(
 	}
 
 	// TODO: Revist this to ensure we don't replace a current state mxid_mapping with an older one.
-	if event.Version() == gomatrixserverlib.RoomVersionPseudoIDs && event.Type() == spec.MRoomMember {
+	if (event.Version() == gomatrixserverlib.RoomVersionPseudoIDs || event.Version() == gomatrixserverlib.RoomVersionCryptoIDs) && event.Type() == spec.MRoomMember {
 		mapping := gomatrixserverlib.MemberContent{}
 		if err = json.Unmarshal(event.Content(), &mapping); err != nil {
 			return err

roomserver/internal/perform/perform_admin.go

@@ -179,7 +179,7 @@ func (r *Admin) PerformAdminEvacuateUser(
 			Leaver: *fullUserID,
 		}
 		leaveRes := &api.PerformLeaveResponse{}
-		outputEvents, err := r.Leaver.PerformLeave(ctx, leaveReq, leaveRes)
+		outputEvents, _, err := r.Leaver.PerformLeave(ctx, leaveReq, leaveRes, false)
 		if err != nil {
 			return nil, err
 		}

roomserver/internal/perform/perform_create_room.go

@@ -44,6 +44,417 @@ type Creator struct {
 	RSAPI api.RoomserverInternalAPI
 }
 
+// PerformCreateRoomCryptoIDs handles all the steps necessary to create a new room.
+// nolint: gocyclo
+func (c *Creator) PerformCreateRoomCryptoIDs(ctx context.Context, userID spec.UserID, roomID spec.RoomID, createRequest *api.PerformCreateRoomRequest) ([]gomatrixserverlib.PDU, error) {
+	verImpl, err := gomatrixserverlib.GetRoomVersion(createRequest.RoomVersion)
+	if err != nil {
+		return nil, spec.BadJSON("unknown room version")
+	}
+
+	createContent := map[string]interface{}{}
+	if len(createRequest.CreationContent) > 0 {
+		if err = json.Unmarshal(createRequest.CreationContent, &createContent); err != nil {
+			util.GetLogger(ctx).WithError(err).Error("json.Unmarshal for creation_content failed")
+			return nil, spec.BadJSON("invalid create content")
+		}
+	}
+
+	senderID := spec.SenderID(createRequest.SenderID)
+
+	// TODO: cryptoIDs - should we be assigning a room NID yet?
+	_, err = c.DB.AssignRoomNID(ctx, roomID, createRequest.RoomVersion)
+	if err != nil {
+		util.GetLogger(ctx).WithError(err).Error("failed to assign roomNID")
+		return nil, spec.InternalServerError{Err: err.Error()}
+	}
+
+	if createRequest.RoomVersion == gomatrixserverlib.RoomVersionCryptoIDs {
+		util.GetLogger(ctx).Infof("StoreUserRoomPublicKey - SenderID: %s UserID: %s RoomID: %s", senderID, userID.String(), roomID.String())
+		bytes := spec.Base64Bytes{}
+		err = bytes.Decode(string(senderID))
+		if err != nil {
+			return nil, err
+		}
+		if len(bytes) != ed25519.PublicKeySize {
+			return nil, spec.BadJSON("SenderID is not a valid ed25519 public key")
+		}
+
+		keyErr := c.RSAPI.StoreUserRoomPublicKey(ctx, senderID, userID, roomID)
+		if keyErr != nil {
+			util.GetLogger(ctx).WithError(keyErr).Error("StoreUserRoomPublicKey failed")
+			return nil, spec.InternalServerError{Err: keyErr.Error()}
+		}
+	}
+
+	createContent["creator"] = senderID
+	createContent["room_version"] = createRequest.RoomVersion
+	powerLevelContent := eventutil.InitialPowerLevelsContent(string(senderID))
+	joinRuleContent := gomatrixserverlib.JoinRuleContent{
+		JoinRule: spec.Invite,
+	}
+	historyVisibilityContent := gomatrixserverlib.HistoryVisibilityContent{
+		HistoryVisibility: historyVisibilityShared,
+	}
+
+	if createRequest.PowerLevelContentOverride != nil {
+		// Merge powerLevelContentOverride fields by unmarshalling it atop the defaults
+		err = json.Unmarshal(createRequest.PowerLevelContentOverride, &powerLevelContent)
+		if err != nil {
+			util.GetLogger(ctx).WithError(err).Error("json.Unmarshal for power_level_content_override failed")
+			return nil, spec.BadJSON("malformed power_level_content_override")
+		}
+	}
+
+	var guestsCanJoin bool
+	switch createRequest.StatePreset {
+	case spec.PresetPrivateChat:
+		joinRuleContent.JoinRule = spec.Invite
+		historyVisibilityContent.HistoryVisibility = historyVisibilityShared
+		guestsCanJoin = true
+	case spec.PresetTrustedPrivateChat:
+		joinRuleContent.JoinRule = spec.Invite
+		historyVisibilityContent.HistoryVisibility = historyVisibilityShared
+		for _, invitee := range createRequest.InvitedUsers {
+			powerLevelContent.Users[invitee] = 100
+		}
+		guestsCanJoin = true
+	case spec.PresetPublicChat:
+		joinRuleContent.JoinRule = spec.Public
+		historyVisibilityContent.HistoryVisibility = historyVisibilityShared
+	}
+
+	createEvent := gomatrixserverlib.FledglingEvent{
+		Type:    spec.MRoomCreate,
+		Content: createContent,
+	}
+	powerLevelEvent := gomatrixserverlib.FledglingEvent{
+		Type:    spec.MRoomPowerLevels,
+		Content: powerLevelContent,
+	}
+	joinRuleEvent := gomatrixserverlib.FledglingEvent{
+		Type:    spec.MRoomJoinRules,
+		Content: joinRuleContent,
+	}
+	historyVisibilityEvent := gomatrixserverlib.FledglingEvent{
+		Type:    spec.MRoomHistoryVisibility,
+		Content: historyVisibilityContent,
+	}
+	membershipEvent := gomatrixserverlib.FledglingEvent{
+		Type:     spec.MRoomMember,
+		StateKey: string(senderID),
+	}
+
+	memberContent := gomatrixserverlib.MemberContent{
+		Membership:  spec.Join,
+		DisplayName: createRequest.UserDisplayName,
+		AvatarURL:   createRequest.UserAvatarURL,
+	}
+
+	// If we are creating a room with pseudo IDs, create and sign the MXIDMapping
+	if createRequest.RoomVersion == gomatrixserverlib.RoomVersionCryptoIDs {
+		mapping := &gomatrixserverlib.MXIDMapping{
+			UserRoomKey: senderID,
+			UserID:      userID.String(),
+		}
+
+		identity, idErr := c.Cfg.Matrix.SigningIdentityFor(userID.Domain()) // we MUST use the server signing mxid_mapping
+		if idErr != nil {
+			logrus.WithError(idErr).WithField("domain", userID.Domain()).Error("unable to find signing identity for domain")
+			return nil, spec.InternalServerError{Err: idErr.Error()}
+		}
+
+		// Sign the mapping with the server identity
+		if err = mapping.Sign(identity.ServerName, identity.KeyID, identity.PrivateKey); err != nil {
+			return nil, spec.InternalServerError{Err: err.Error()}
+		}
+		memberContent.MXIDMapping = mapping
+	}
+	membershipEvent.Content = memberContent
+
+	var nameEvent *gomatrixserverlib.FledglingEvent
+	var topicEvent *gomatrixserverlib.FledglingEvent
+	var guestAccessEvent *gomatrixserverlib.FledglingEvent
+	var aliasEvent *gomatrixserverlib.FledglingEvent
+
+	if createRequest.RoomName != "" {
+		nameEvent = &gomatrixserverlib.FledglingEvent{
+			Type: spec.MRoomName,
+			Content: eventutil.NameContent{
+				Name: createRequest.RoomName,
+			},
+		}
+	}
+
+	if createRequest.Topic != "" {
+		topicEvent = &gomatrixserverlib.FledglingEvent{
+			Type: spec.MRoomTopic,
+			Content: eventutil.TopicContent{
+				Topic: createRequest.Topic,
+			},
+		}
+	}
+
+	if guestsCanJoin {
+		guestAccessEvent = &gomatrixserverlib.FledglingEvent{
+			Type: spec.MRoomGuestAccess,
+			Content: eventutil.GuestAccessContent{
+				GuestAccess: "can_join",
+			},
+		}
+	}
+
+	var roomAlias string
+	if createRequest.RoomAliasName != "" {
+		roomAlias = fmt.Sprintf("#%s:%s", createRequest.RoomAliasName, userID.Domain())
+		// check it's free
+		// TODO: This races but is better than nothing
+		hasAliasReq := api.GetRoomIDForAliasRequest{
+			Alias:              roomAlias,
+			IncludeAppservices: false,
+		}
+
+		var aliasResp api.GetRoomIDForAliasResponse
+		err = c.RSAPI.GetRoomIDForAlias(ctx, &hasAliasReq, &aliasResp)
+		if err != nil {
+			util.GetLogger(ctx).WithError(err).Error("aliasAPI.GetRoomIDForAlias failed")
+			return nil, spec.InternalServerError{Err: err.Error()}
+		}
+		if aliasResp.RoomID != "" {
+			return nil, spec.RoomInUse("Room ID already exists.")
+		}
+
+		aliasEvent = &gomatrixserverlib.FledglingEvent{
+			Type: spec.MRoomCanonicalAlias,
+			Content: eventutil.CanonicalAlias{
+				Alias: roomAlias,
+			},
+		}
+	}
+
+	var initialStateEvents []gomatrixserverlib.FledglingEvent
+	for i := range createRequest.InitialState {
+		if createRequest.InitialState[i].StateKey != "" {
+			initialStateEvents = append(initialStateEvents, createRequest.InitialState[i])
+			continue
+		}
+
+		switch createRequest.InitialState[i].Type {
+		case spec.MRoomCreate:
+			continue
+
+		case spec.MRoomPowerLevels:
+			powerLevelEvent = createRequest.InitialState[i]
+
+		case spec.MRoomJoinRules:
+			joinRuleEvent = createRequest.InitialState[i]
+
+		case spec.MRoomHistoryVisibility:
+			historyVisibilityEvent = createRequest.InitialState[i]
+
+		case spec.MRoomGuestAccess:
+			guestAccessEvent = &createRequest.InitialState[i]
+
+		case spec.MRoomName:
+			nameEvent = &createRequest.InitialState[i]
+
+		case spec.MRoomTopic:
+			topicEvent = &createRequest.InitialState[i]
+
+		default:
+			initialStateEvents = append(initialStateEvents, createRequest.InitialState[i])
+		}
+	}
+
+	// send events into the room in order of:
+	//  1- m.room.create
+	//  2- room creator join member
+	//  3- m.room.power_levels
+	//  4- m.room.join_rules
+	//  5- m.room.history_visibility
+	//  6- m.room.canonical_alias (opt)
+	//  7- m.room.guest_access (opt)
+	//  8- other initial state items
+	//  9- m.room.name (opt)
+	//  10- m.room.topic (opt)
+	//  11- invite events (opt) - with is_direct flag if applicable TODO
+	//  12- 3pid invite events (opt) TODO
+	// This differs from Synapse slightly. Synapse would vary the ordering of 3-7
+	// depending on if those events were in "initial_state" or not. This made it
+	// harder to reason about, hence sticking to a strict static ordering.
+	eventsToMake := []gomatrixserverlib.FledglingEvent{
+		createEvent, membershipEvent, powerLevelEvent, joinRuleEvent, historyVisibilityEvent,
+	}
+	if guestAccessEvent != nil {
+		eventsToMake = append(eventsToMake, *guestAccessEvent)
+	}
+	eventsToMake = append(eventsToMake, initialStateEvents...)
+	if nameEvent != nil {
+		eventsToMake = append(eventsToMake, *nameEvent)
+	}
+	if topicEvent != nil {
+		eventsToMake = append(eventsToMake, *topicEvent)
+	}
+	if aliasEvent != nil {
+		// TODO: bit of a chicken and egg problem here as the alias doesn't exist and cannot until we have made the room.
+		// This means we might fail creating the alias but say the canonical alias is something that doesn't exist.
+		eventsToMake = append(eventsToMake, *aliasEvent)
+	}
+
+	var builtEvents []gomatrixserverlib.PDU
+	authEvents := gomatrixserverlib.NewAuthEvents(nil)
+	if err != nil {
+		util.GetLogger(ctx).WithError(err).Error("rsapi.QuerySenderIDForUser failed")
+		return nil, spec.InternalServerError{Err: err.Error()}
+	}
+	for i, e := range eventsToMake {
+		depth := i + 1 // depth starts at 1
+
+		builder := verImpl.NewEventBuilderFromProtoEvent(&gomatrixserverlib.ProtoEvent{
+			SenderID: string(senderID),
+			RoomID:   roomID.String(),
+			Type:     e.Type,
+			StateKey: &e.StateKey,
+			Depth:    int64(depth),
+		})
+		err = builder.SetContent(e.Content)
+		if err != nil {
+			util.GetLogger(ctx).WithError(err).Error("builder.SetContent failed")
+			return nil, spec.InternalServerError{Err: err.Error()}
+		}
+		if i > 0 {
+			builder.PrevEvents = []string{builtEvents[i-1].EventID()}
+		}
+		var ev gomatrixserverlib.PDU
+		if err = builder.AddAuthEvents(&authEvents); err != nil {
+			util.GetLogger(ctx).WithError(err).Error("AddAuthEvents failed")
+			return nil, spec.InternalServerError{Err: err.Error()}
+		}
+
+		ev, err = builder.BuildWithoutSigning(createRequest.EventTime, userID.Domain())
+		if err != nil {
+			util.GetLogger(ctx).WithError(err).Error("buildEvent failed")
+			return nil, spec.InternalServerError{Err: err.Error()}
+		}
+
+		if err = gomatrixserverlib.Allowed(ev, &authEvents, func(roomID spec.RoomID, senderID spec.SenderID) (*spec.UserID, error) {
+			return c.RSAPI.QueryUserIDForSender(ctx, roomID, senderID)
+		}); err != nil {
+			util.GetLogger(ctx).WithError(err).Error("gomatrixserverlib.Allowed failed")
+			return nil, spec.InternalServerError{Err: err.Error()}
+		}
+
+		// Add the event to the list of auth events
+		builtEvents = append(builtEvents, ev)
+		err = authEvents.AddEvent(ev)
+		if err != nil {
+			util.GetLogger(ctx).WithError(err).Error("authEvents.AddEvent failed")
+			return nil, spec.InternalServerError{Err: err.Error()}
+		}
+	}
+
+	// TODO(#269): Reserve room alias while we create the room. This stops us
+	// from creating the room but still failing due to the alias having already
+	// been taken.
+	if roomAlias != "" {
+		aliasAlreadyExists, aliasErr := c.RSAPI.SetRoomAlias(ctx, senderID, roomID, roomAlias)
+		if aliasErr != nil {
+			util.GetLogger(ctx).WithError(aliasErr).Error("aliasAPI.SetRoomAlias failed")
+			return nil, spec.InternalServerError{Err: aliasErr.Error()}
+		}
+
+		if aliasAlreadyExists {
+			return nil, spec.RoomInUse("Room alias already exists.")
+		}
+	}
+
+	// TODO: cryptoIDs - this shouldn't really be done until the client calls /sendPDUs with these events
+	// But that would require the visibility setting also being passed along
+	if createRequest.Visibility == spec.Public {
+		// expose this room in the published room list
+		if err = c.RSAPI.PerformPublish(ctx, &api.PerformPublishRequest{
+			RoomID:     roomID.String(),
+			Visibility: spec.Public,
+		}); err != nil {
+			util.GetLogger(ctx).WithError(err).Error("failed to publish room")
+			return nil, spec.InternalServerError{Err: err.Error()}
+		}
+	}
+
+	// If this is a direct message then we should invite the participants.
+	//if len(createRequest.InvitedUsers) > 0 {
+	// Build some stripped state for the invite.
+	//var globalStrippedState []gomatrixserverlib.InviteStrippedState
+	//for _, event := range builtEvents {
+	//	// Chosen events from the spec:
+	//	// https://spec.matrix.org/v1.3/client-server-api/#stripped-state
+	//	switch event.Type() {
+	//	case spec.MRoomCreate:
+	//		fallthrough
+	//	case spec.MRoomName:
+	//		fallthrough
+	//	case spec.MRoomAvatar:
+	//		fallthrough
+	//	case spec.MRoomTopic:
+	//		fallthrough
+	//	case spec.MRoomCanonicalAlias:
+	//		fallthrough
+	//	case spec.MRoomEncryption:
+	//		fallthrough
+	//	case spec.MRoomMember:
+	//		fallthrough
+	//	case spec.MRoomJoinRules:
+	//		ev := event
+	//		globalStrippedState = append(
+	//			globalStrippedState,
+	//			gomatrixserverlib.NewInviteStrippedState(ev),
+	//		)
+	//	}
+	//}
+
+	// Process the invites.
+	//for _, invitee := range createRequest.InvitedUsers {
+	//inviteeUserID, userIDErr := spec.NewUserID(invitee, true)
+	//if userIDErr != nil {
+	//	util.GetLogger(ctx).WithError(userIDErr).Error("invalid UserID")
+	//	return nil, spec.InternalServerError{}
+	//}
+
+	// TODO: cryptoIDs - these shouldn't be here
+	// instead we should return proto invite events?
+	//err = c.RSAPI.PerformInvite(ctx, &api.PerformInviteRequest{
+	//	InviteInput: api.InviteInput{
+	//		RoomID:      roomID,
+	//		Inviter:     userID,
+	//		Invitee:     *inviteeUserID,
+	//		DisplayName: createRequest.UserDisplayName,
+	//		AvatarURL:   createRequest.UserAvatarURL,
+	//		Reason:      "",
+	//		IsDirect:    createRequest.IsDirect,
+	//		KeyID:       createRequest.KeyID,
+	//		PrivateKey:  createRequest.PrivateKey,
+	//		EventTime:   createRequest.EventTime,
+	//	},
+	//	InviteRoomState: globalStrippedState,
+	//	SendAsServer:    string(userID.Domain()),
+	//})
+	//switch e := err.(type) {
+	//case api.ErrInvalidID:
+	//	return nil, spec.Unknown(e.Error())
+	//case api.ErrNotAllowed:
+	//	return nil, spec.Forbidden(e.Error())
+	//case nil:
+	//default:
+	//	util.GetLogger(ctx).WithError(err).Error("PerformInvite failed")
+	//	sentry.CaptureException(err)
+	//	return nil, spec.InternalServerError{}
+	//}
+	//}
+	//}
+
+	return builtEvents, nil
+}
+
 // PerformCreateRoom handles all the steps necessary to create a new room.
 // nolint: gocyclo
 func (c *Creator) PerformCreateRoom(ctx context.Context, userID spec.UserID, roomID spec.RoomID, createRequest *api.PerformCreateRoomRequest) (string, *util.JSONResponse) {
@@ -501,7 +912,7 @@ func (c *Creator) PerformCreateRoom(ctx context.Context, userID spec.UserID, roo
 				}
 			}
 
-			err = c.RSAPI.PerformInvite(ctx, &api.PerformInviteRequest{
+			_, err = c.RSAPI.PerformInvite(ctx, &api.PerformInviteRequest{
 				InviteInput: api.InviteInput{
 					RoomID:      roomID,
 					Inviter:     userID,
@@ -516,7 +927,7 @@ func (c *Creator) PerformCreateRoom(ctx context.Context, userID spec.UserID, roo
 				},
 				InviteRoomState: globalStrippedState,
 				SendAsServer:    string(userID.Domain()),
-			})
+			}, false)
 			switch e := err.(type) {
 			case api.ErrInvalidID:
 				return "", &util.JSONResponse{

roomserver/internal/perform/perform_invite.go

@@ -125,16 +125,17 @@ func (r *Inviter) ProcessInviteMembership(
 func (r *Inviter) PerformInvite(
 	ctx context.Context,
 	req *api.PerformInviteRequest,
-) error {
+	cryptoIDs bool,
+) (gomatrixserverlib.PDU, error) {
 	senderID, err := r.RSAPI.QuerySenderIDForUser(ctx, req.InviteInput.RoomID, req.InviteInput.Inviter)
 	if err != nil {
-		return err
+		return nil, err
 	} else if senderID == nil {
-		return fmt.Errorf("sender ID not found for %s in %s", req.InviteInput.Inviter, req.InviteInput.RoomID)
+		return nil, fmt.Errorf("sender ID not found for %s in %s", req.InviteInput.Inviter, req.InviteInput.RoomID)
 	}
 	info, err := r.DB.RoomInfo(ctx, req.InviteInput.RoomID.String())
 	if err != nil {
-		return err
+		return nil, err
 	}
 
 	proto := gomatrixserverlib.ProtoEvent{
@@ -152,20 +153,20 @@ func (r *Inviter) PerformInvite(
 	}
 
 	if err = proto.SetContent(content); err != nil {
-		return err
+		return nil, err
 	}
 
 	if !r.Cfg.Matrix.IsLocalServerName(req.InviteInput.Inviter.Domain()) {
-		return api.ErrInvalidID{Err: fmt.Errorf("the invite must be from a local user")}
+		return nil, api.ErrInvalidID{Err: fmt.Errorf("the invite must be from a local user")}
 	}
 
 	isTargetLocal := r.Cfg.Matrix.IsLocalServerName(req.InviteInput.Invitee.Domain())
 
 	signingKey := req.InviteInput.PrivateKey
-	if info.RoomVersion == gomatrixserverlib.RoomVersionPseudoIDs {
+	if !cryptoIDs && info.RoomVersion == gomatrixserverlib.RoomVersionPseudoIDs {
 		signingKey, err = r.RSAPI.GetOrCreateUserRoomPrivateKey(ctx, req.InviteInput.Inviter, req.InviteInput.RoomID)
 		if err != nil {
-			return err
+			return nil, err
 		}
 	}
 
@@ -222,6 +223,10 @@ func (r *Inviter) PerformInvite(
 			}
 			return r.RSAPI.StoreUserRoomPublicKey(ctx, senderID, *storeUserID, roomID)
 		},
+		CryptoIDs: cryptoIDs,
+		ClaimSenderID: func(ctx context.Context, roomID spec.RoomID, userID spec.UserID) (spec.SenderID, error) {
+			return r.RSAPI.ClaimOneTimeSenderIDForUser(ctx, roomID, userID)
+		},
 	}
 
 	inviteEvent, err := gomatrixserverlib.PerformInvite(ctx, input, r.FSAPI)
@@ -229,12 +234,14 @@ func (r *Inviter) PerformInvite(
 		switch e := err.(type) {
 		case spec.MatrixError:
 			if e.ErrCode == spec.ErrorForbidden {
-				return api.ErrNotAllowed{Err: fmt.Errorf("%s", e.Err)}
+				return nil, api.ErrNotAllowed{Err: fmt.Errorf("%s", e.Err)}
 			}
 		}
-		return err
+		return nil, err
 	}
 
+	var response gomatrixserverlib.PDU
+	if !cryptoIDs {
 		// Send the invite event to the roomserver input stream. This will
 		// notify existing users in the room about the invite, update the
 		// membership table and ensure that the event is ready and available
@@ -254,8 +261,11 @@ func (r *Inviter) PerformInvite(
 		r.Inputer.InputRoomEvents(context.Background(), inputReq, inputRes)
 		if err := inputRes.Err(); err != nil {
 			util.GetLogger(ctx).WithField("event_id", inviteEvent.EventID()).Error("r.InputRoomEvents failed")
-		return api.ErrNotAllowed{Err: err}
+			return nil, api.ErrNotAllowed{Err: err}
+		}
+	} else {
+		response = inviteEvent
 	}
 
-	return nil
+	return response, nil
 }

roomserver/internal/perform/perform_join.go

@@ -406,6 +406,380 @@ func (r *Joiner) performJoinRoomByID(
 	return req.RoomIDOrAlias, userDomain, nil
 }
 
+func (r *Joiner) PerformSendJoinCryptoIDs(
+	ctx context.Context,
+	req *rsAPI.PerformJoinRequestCryptoIDs,
+) error {
+	logger := logrus.WithContext(ctx).WithFields(logrus.Fields{
+		"room_id": req.RoomID,
+		"user_id": req.UserID,
+		"servers": req.ServerNames,
+	})
+	logger.Info("performing send join")
+	res := fsAPI.PerformJoinResponse{}
+	r.FSAPI.PerformSendJoin(ctx, &fsAPI.PerformSendJoinRequestCryptoIDs{
+		RoomID:      req.RoomID,
+		UserID:      req.UserID,
+		ServerNames: req.ServerNames,
+		Unsigned:    req.Unsigned,
+		Event:       req.JoinEvent,
+	}, &res)
+	if res.LastError != nil {
+		return res.LastError
+	}
+
+	return nil
+}
+
+func (r *Joiner) PerformSendInviteCryptoIDs(
+	ctx context.Context,
+	req *rsAPI.PerformInviteRequestCryptoIDs,
+) error {
+	logger := logrus.WithContext(ctx).WithFields(logrus.Fields{
+		"room_id": req.RoomID,
+		"user_id": req.UserID,
+	})
+	logger.Info("performing send invite")
+	err := r.FSAPI.SendInviteCryptoIDs(ctx, req.InviteEvent, req.UserID, req.InviteEvent.Version())
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// PerformJoin handles joining matrix rooms, including over federation by talking to the federationapi.
+func (r *Joiner) PerformJoinCryptoIDs(
+	ctx context.Context,
+	req *rsAPI.PerformJoinRequest,
+) (joinEvent gomatrixserverlib.PDU, roomID string, version gomatrixserverlib.RoomVersion, serverName spec.ServerName, err error) {
+	logger := logrus.WithContext(ctx).WithFields(logrus.Fields{
+		"room_id": req.RoomIDOrAlias,
+		"user_id": req.UserID,
+		"servers": req.ServerNames,
+	})
+	logger.Info("User requested to room join")
+	join, roomID, version, serverName, err := r.makeJoinEvent(context.Background(), req)
+	if err != nil {
+		logger.WithError(err).Error("Failed to make join room event")
+		sentry.CaptureException(err)
+		return nil, "", "", "", err
+	}
+
+	return join, roomID, version, serverName, nil
+}
+
+func (r *Joiner) makeJoinEvent(
+	ctx context.Context,
+	req *rsAPI.PerformJoinRequest,
+) (gomatrixserverlib.PDU, string, gomatrixserverlib.RoomVersion, spec.ServerName, error) {
+	_, domain, err := gomatrixserverlib.SplitID('@', req.UserID)
+	if err != nil {
+		return nil, "", "", "", rsAPI.ErrInvalidID{Err: fmt.Errorf("supplied user ID %q in incorrect format", req.UserID)}
+	}
+	if !r.Cfg.Matrix.IsLocalServerName(domain) {
+		return nil, "", "", "", rsAPI.ErrInvalidID{Err: fmt.Errorf("user %q does not belong to this homeserver", req.UserID)}
+	}
+	if strings.HasPrefix(req.RoomIDOrAlias, "!") {
+		return r.performJoinRoomByIDCryptoIDs(ctx, req)
+	}
+	if strings.HasPrefix(req.RoomIDOrAlias, "#") {
+		return r.performJoinRoomByAliasCryptoIDs(ctx, req)
+	}
+	return nil, "", "", "", rsAPI.ErrInvalidID{Err: fmt.Errorf("room ID or alias %q is invalid", req.RoomIDOrAlias)}
+}
+
+func (r *Joiner) performJoinRoomByAliasCryptoIDs(
+	ctx context.Context,
+	req *rsAPI.PerformJoinRequest,
+) (gomatrixserverlib.PDU, string, gomatrixserverlib.RoomVersion, spec.ServerName, error) {
+	// Get the domain part of the room alias.
+	_, domain, err := gomatrixserverlib.SplitID('#', req.RoomIDOrAlias)
+	if err != nil {
+		return nil, "", "", "", fmt.Errorf("alias %q is not in the correct format", req.RoomIDOrAlias)
+	}
+	req.ServerNames = append(req.ServerNames, domain)
+
+	// Check if this alias matches our own server configuration. If it
+	// doesn't then we'll need to try a federated join.
+	var roomID string
+	if !r.Cfg.Matrix.IsLocalServerName(domain) {
+		// The alias isn't owned by us, so we will need to try joining using
+		// a remote server.
+		dirReq := fsAPI.PerformDirectoryLookupRequest{
+			RoomAlias:  req.RoomIDOrAlias, // the room alias to lookup
+			ServerName: domain,            // the server to ask
+		}
+		dirRes := fsAPI.PerformDirectoryLookupResponse{}
+		err = r.FSAPI.PerformDirectoryLookup(ctx, &dirReq, &dirRes)
+		if err != nil {
+			logrus.WithError(err).Errorf("error looking up alias %q", req.RoomIDOrAlias)
+			return nil, "", "", "", fmt.Errorf("looking up alias %q over federation failed: %w", req.RoomIDOrAlias, err)
+		}
+		roomID = dirRes.RoomID
+		req.ServerNames = append(req.ServerNames, dirRes.ServerNames...)
+	} else {
+		var getRoomReq = rsAPI.GetRoomIDForAliasRequest{
+			Alias:              req.RoomIDOrAlias,
+			IncludeAppservices: true,
+		}
+		var getRoomRes = rsAPI.GetRoomIDForAliasResponse{}
+		// Otherwise, look up if we know this room alias locally.
+		err = r.RSAPI.GetRoomIDForAlias(ctx, &getRoomReq, &getRoomRes)
+		if err != nil {
+			return nil, "", "", "", fmt.Errorf("lookup room alias %q failed: %w", req.RoomIDOrAlias, err)
+		}
+		roomID = getRoomRes.RoomID
+	}
+
+	// If the room ID is empty then we failed to look up the alias.
+	if roomID == "" {
+		return nil, "", "", "", fmt.Errorf("alias %q not found", req.RoomIDOrAlias)
+	}
+
+	// If we do, then pluck out the room ID and continue the join.
+	req.RoomIDOrAlias = roomID
+	return r.performJoinRoomByIDCryptoIDs(ctx, req)
+}
+
+// TODO: Break this function up a bit & move to GMSL
+// nolint:gocyclo
+func (r *Joiner) performJoinRoomByIDCryptoIDs(
+	ctx context.Context,
+	req *rsAPI.PerformJoinRequest,
+) (gomatrixserverlib.PDU, string, gomatrixserverlib.RoomVersion, spec.ServerName, error) {
+	// The original client request ?server_name=... may include this HS so filter that out so we
+	// don't attempt to make_join with ourselves
+	for i := 0; i < len(req.ServerNames); i++ {
+		if r.Cfg.Matrix.IsLocalServerName(req.ServerNames[i]) {
+			// delete this entry
+			req.ServerNames = append(req.ServerNames[:i], req.ServerNames[i+1:]...)
+			i--
+		}
+	}
+
+	// Get the domain part of the room ID.
+	roomID, err := spec.NewRoomID(req.RoomIDOrAlias)
+	if err != nil {
+		return nil, "", "", "", rsAPI.ErrInvalidID{Err: fmt.Errorf("room ID %q is invalid: %w", req.RoomIDOrAlias, err)}
+	}
+
+	// If the server name in the room ID isn't ours then it's a
+	// possible candidate for finding the room via federation. Add
+	// it to the list of servers to try.
+	if !r.Cfg.Matrix.IsLocalServerName(roomID.Domain()) {
+		req.ServerNames = append(req.ServerNames, roomID.Domain())
+	}
+
+	// Force a federated join if we aren't in the room and we've been
+	// given some server names to try joining by.
+	inRoomReq := &rsAPI.QueryServerJoinedToRoomRequest{
+		RoomID: req.RoomIDOrAlias,
+	}
+	inRoomRes := &rsAPI.QueryServerJoinedToRoomResponse{}
+	if err = r.Queryer.QueryServerJoinedToRoom(ctx, inRoomReq, inRoomRes); err != nil {
+		return nil, "", "", "", fmt.Errorf("r.Queryer.QueryServerJoinedToRoom: %w", err)
+	}
+	serverInRoom := inRoomRes.IsInRoom
+	forceFederatedJoin := len(req.ServerNames) > 0 && !serverInRoom
+
+	userID, err := spec.NewUserID(req.UserID, true)
+	if err != nil {
+		return nil, "", "", "", rsAPI.ErrInvalidID{Err: fmt.Errorf("user ID %q is invalid: %w", req.UserID, err)}
+	}
+
+	//TODO: CryptoIDs - what is provided & calculated senderIDs don't match?
+
+	// Look up the room NID for the supplied room ID.
+	var senderID spec.SenderID
+	checkInvitePending := false
+	info, err := r.DB.RoomInfo(ctx, req.RoomIDOrAlias)
+	if err == nil && info != nil {
+		switch info.RoomVersion {
+		case gomatrixserverlib.RoomVersionCryptoIDs:
+			senderIDPtr, queryErr := r.Queryer.QuerySenderIDForUser(ctx, *roomID, *userID)
+			if queryErr == nil {
+				checkInvitePending = true
+			}
+			if senderIDPtr == nil {
+				senderID = req.SenderID
+			} else {
+				senderID = *senderIDPtr
+			}
+		default:
+			checkInvitePending = true
+			senderID = spec.SenderID(userID.String())
+		}
+	}
+
+	// Force a federated join if we're dealing with a pending invite
+	// and we aren't in the room.
+	if checkInvitePending {
+		isInvitePending, inviteSender, _, inviteEvent, inviteErr := helpers.IsInvitePending(ctx, r.DB, req.RoomIDOrAlias, senderID)
+		if inviteErr == nil && !serverInRoom && isInvitePending {
+			inviter, queryErr := r.RSAPI.QueryUserIDForSender(ctx, *roomID, inviteSender)
+			if queryErr != nil {
+				return nil, "", "", "", fmt.Errorf("r.RSAPI.QueryUserIDForSender: %w", queryErr)
+			}
+
+			// If we were invited by someone from another server then we can
+			// assume they are in the room so we can join via them.
+			if inviter != nil && !r.Cfg.Matrix.IsLocalServerName(inviter.Domain()) {
+				req.ServerNames = append(req.ServerNames, inviter.Domain())
+				forceFederatedJoin = true
+				memberEvent := gjson.Parse(string(inviteEvent.JSON()))
+				// only set unsigned if we've got a content.membership, which we _should_
+				if memberEvent.Get("content.membership").Exists() {
+					req.Unsigned = map[string]interface{}{
+						"prev_sender": memberEvent.Get("sender").Str,
+						"prev_content": map[string]interface{}{
+							"is_direct":  memberEvent.Get("content.is_direct").Bool(),
+							"membership": memberEvent.Get("content.membership").Str,
+						},
+					}
+				}
+			}
+		}
+	}
+
+	// If a guest is trying to join a room, check that the room has a m.room.guest_access event
+	if req.IsGuest {
+		var guestAccessEvent *types.HeaderedEvent
+		guestAccess := "forbidden"
+		guestAccessEvent, err = r.DB.GetStateEvent(ctx, req.RoomIDOrAlias, spec.MRoomGuestAccess, "")
+		if (err != nil && !errors.Is(err, sql.ErrNoRows)) || guestAccessEvent == nil {
+			logrus.WithError(err).Warn("unable to get m.room.guest_access event, defaulting to 'forbidden'")
+		}
+		if guestAccessEvent != nil {
+			guestAccess = gjson.GetBytes(guestAccessEvent.Content(), "guest_access").String()
+		}
+
+		// Servers MUST only allow guest users to join rooms if the m.room.guest_access state event
+		// is present on the room and has the guest_access value can_join.
+		if guestAccess != "can_join" {
+			return nil, "", "", "", rsAPI.ErrNotAllowed{Err: fmt.Errorf("guest access is forbidden")}
+		}
+	}
+
+	// If we should do a forced federated join then do that.
+	if forceFederatedJoin {
+		joinEvent, version, serverName, federatedJoinErr := r.performFederatedMakeJoinByIDCryptoIDs(ctx, req)
+		return joinEvent, req.RoomIDOrAlias, version, serverName, federatedJoinErr
+	}
+
+	// Try to construct an actual join event from the template.
+	// If this succeeds then it is a sign that the room already exists
+	// locally on the homeserver.
+	// TODO: Check what happens if the room exists on the server
+	// but everyone has since left. I suspect it does the wrong thing.
+
+	var buildRes rsAPI.QueryLatestEventsAndStateResponse
+	identity := r.Cfg.Matrix.SigningIdentity
+
+	// at this point we know we have an existing room
+	if inRoomRes.RoomVersion == gomatrixserverlib.RoomVersionCryptoIDs {
+		mapping := &gomatrixserverlib.MXIDMapping{
+			UserRoomKey: senderID,
+			UserID:      userID.String(),
+		}
+
+		// Sign the mapping with the server identity
+		if err = mapping.Sign(identity.ServerName, identity.KeyID, identity.PrivateKey); err != nil {
+			return nil, "", "", "", err
+		}
+		req.Content["mxid_mapping"] = mapping
+
+		// sign the event with the pseudo ID key
+		identity = fclient.SigningIdentity{
+			ServerName: spec.ServerName(senderID),
+			KeyID:      "ed25519:1",
+			PrivateKey: nil,
+		}
+	}
+
+	senderIDString := string(senderID)
+
+	// Prepare the template for the join event.
+	proto := gomatrixserverlib.ProtoEvent{
+		Type:     spec.MRoomMember,
+		SenderID: senderIDString,
+		StateKey: &senderIDString,
+		RoomID:   req.RoomIDOrAlias,
+		Redacts:  "",
+	}
+	if err = proto.SetUnsigned(struct{}{}); err != nil {
+		return nil, "", "", "", fmt.Errorf("eb.SetUnsigned: %w", err)
+	}
+
+	// It is possible for the request to include some "content" for the
+	// event. We'll always overwrite the "membership" key, but the rest,
+	// like "display_name" or "avatar_url", will be kept if supplied.
+	if req.Content == nil {
+		req.Content = map[string]interface{}{}
+	}
+	req.Content["membership"] = spec.Join
+	if authorisedVia, aerr := r.populateAuthorisedViaUserForRestrictedJoin(ctx, req, senderID); aerr != nil {
+		return nil, "", "", "", aerr
+	} else if authorisedVia != "" {
+		req.Content["join_authorised_via_users_server"] = authorisedVia
+	}
+	if err = proto.SetContent(req.Content); err != nil {
+		return nil, "", "", "", fmt.Errorf("eb.SetContent: %w", err)
+	}
+	joinEvent, err := eventutil.QueryAndBuildEvent(ctx, &proto, &identity, time.Now(), r.RSAPI, &buildRes)
+
+	switch err.(type) {
+	case nil:
+		// Do nothing
+
+	case eventutil.ErrRoomNoExists:
+		// The room doesn't exist locally. If the room ID looks like it should
+		// be ours then this probably means that we've nuked our database at
+		// some point.
+		if r.Cfg.Matrix.IsLocalServerName(roomID.Domain()) {
+			// If there are no more server names to try then give up here.
+			// Otherwise we'll try a federated join as normal, since it's quite
+			// possible that the room still exists on other servers.
+			if len(req.ServerNames) == 0 {
+				return nil, "", "", "", eventutil.ErrRoomNoExists{}
+			}
+		}
+
+		// Perform a federated room join.
+		joinEvent, version, serverName, federatedJoinErr := r.performFederatedMakeJoinByIDCryptoIDs(ctx, req)
+		return joinEvent, req.RoomIDOrAlias, version, serverName, federatedJoinErr
+
+	default:
+		// Something else went wrong.
+		return nil, "", "", "", fmt.Errorf("error joining local room: %q", err)
+	}
+
+	// By this point, if req.RoomIDOrAlias contained an alias, then
+	// it will have been overwritten with a room ID by performJoinRoomByAlias.
+	// We should now include this in the response so that the CS API can
+	// return the right room ID.
+	return joinEvent, req.RoomIDOrAlias, inRoomRes.RoomVersion, userID.Domain(), nil
+}
+
+func (r *Joiner) performFederatedMakeJoinByIDCryptoIDs(
+	ctx context.Context,
+	req *rsAPI.PerformJoinRequest,
+) (gomatrixserverlib.PDU, gomatrixserverlib.RoomVersion, spec.ServerName, error) {
+	// Try joining by all of the supplied server names.
+	fedReq := fsAPI.PerformJoinRequest{
+		RoomID:      req.RoomIDOrAlias, // the room ID to try and join
+		UserID:      req.UserID,        // the user ID joining the room
+		ServerNames: req.ServerNames,   // the server to try joining with
+		Content:     req.Content,       // the membership event content
+		Unsigned:    req.Unsigned,      // the unsigned event content, if any
+	}
+	joinEvent, version, serverName, err := r.FSAPI.PerformMakeJoin(ctx, &fedReq)
+	if err != nil {
+		return nil, "", "", err
+	}
+	return joinEvent, version, serverName, nil
+}
+
 func (r *Joiner) performFederatedJoinRoomByID(
 	ctx context.Context,
 	req *rsAPI.PerformJoinRequest,

roomserver/internal/perform/perform_leave.go

@@ -24,6 +24,7 @@ import (
 	"github.com/matrix-org/dendrite/internal/eventutil"
 	"github.com/matrix-org/gomatrix"
 	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/gomatrixserverlib/fclient"
 	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 	"github.com/sirupsen/logrus"
@@ -52,9 +53,10 @@ func (r *Leaver) PerformLeave(
 	ctx context.Context,
 	req *api.PerformLeaveRequest,
 	res *api.PerformLeaveResponse,
-) ([]api.OutputEvent, error) {
+	cryptoIDs bool,
+) ([]api.OutputEvent, gomatrixserverlib.PDU, error) {
 	if !r.Cfg.Matrix.IsLocalServerName(req.Leaver.Domain()) {
-		return nil, fmt.Errorf("user %q does not belong to this homeserver", req.Leaver.String())
+		return nil, nil, fmt.Errorf("user %q does not belong to this homeserver", req.Leaver.String())
 	}
 	logger := logrus.WithContext(ctx).WithFields(logrus.Fields{
 		"room_id": req.RoomID,
@@ -62,15 +64,15 @@ func (r *Leaver) PerformLeave(
 	})
 	logger.Info("User requested to leave join")
 	if strings.HasPrefix(req.RoomID, "!") {
-		output, err := r.performLeaveRoomByID(context.Background(), req, res)
+		output, event, err := r.performLeaveRoomByID(context.Background(), req, res, cryptoIDs)
 		if err != nil {
 			logger.WithError(err).Error("Failed to leave room")
 		} else {
 			logger.Info("User left room successfully")
 		}
-		return output, err
+		return output, event, err
 	}
-	return nil, fmt.Errorf("room ID %q is invalid", req.RoomID)
+	return nil, nil, fmt.Errorf("room ID %q is invalid", req.RoomID)
 }
 
 // nolint:gocyclo
@@ -78,14 +80,15 @@ func (r *Leaver) performLeaveRoomByID(
 	ctx context.Context,
 	req *api.PerformLeaveRequest,
 	res *api.PerformLeaveResponse, // nolint:unparam
-) ([]api.OutputEvent, error) {
+	cryptoIDs bool,
+) ([]api.OutputEvent, gomatrixserverlib.PDU, error) {
 	roomID, err := spec.NewRoomID(req.RoomID)
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 	leaver, err := r.RSAPI.QuerySenderIDForUser(ctx, *roomID, req.Leaver)
 	if err != nil || leaver == nil {
-		return nil, fmt.Errorf("leaver %s has no matching senderID in this room", req.Leaver.String())
+		return nil, nil, fmt.Errorf("leaver %s has no matching senderID in this room", req.Leaver.String())
 	}
 
 	// If there's an invite outstanding for the room then respond to
@@ -94,7 +97,7 @@ func (r *Leaver) performLeaveRoomByID(
 	if err == nil && isInvitePending {
 		sender, serr := r.RSAPI.QueryUserIDForSender(ctx, *roomID, senderUser)
 		if serr != nil {
-			return nil, fmt.Errorf("failed looking up userID for sender %q: %w", senderUser, serr)
+			return nil, nil, fmt.Errorf("failed looking up userID for sender %q: %w", senderUser, serr)
 		}
 
 		var domain spec.ServerName
@@ -107,7 +110,7 @@ func (r *Leaver) performLeaveRoomByID(
 			domain = sender.Domain()
 		}
 		if !r.Cfg.Matrix.IsLocalServerName(domain) {
-			return r.performFederatedRejectInvite(ctx, req, res, domain, eventID, *leaver)
+			return r.performFederatedRejectInvite(ctx, req, res, domain, eventID, *leaver, cryptoIDs)
 		}
 		// check that this is not a "server notice room"
 		accData := &userapi.QueryAccountDataResponse{}
@@ -116,7 +119,7 @@ func (r *Leaver) performLeaveRoomByID(
 			RoomID:   req.RoomID,
 			DataType: "m.tag",
 		}, accData); err != nil {
-			return nil, fmt.Errorf("unable to query account data: %w", err)
+			return nil, nil, fmt.Errorf("unable to query account data: %w", err)
 		}
 
 		if roomData, ok := accData.RoomAccountData[req.RoomID]; ok {
@@ -124,13 +127,13 @@ func (r *Leaver) performLeaveRoomByID(
 			if ok {
 				tags := gomatrix.TagContent{}
 				if err = json.Unmarshal(tagData, &tags); err != nil {
-					return nil, fmt.Errorf("unable to unmarshal tag content")
+					return nil, nil, fmt.Errorf("unable to unmarshal tag content")
 				}
 				if _, ok = tags.Tags["m.server_notice"]; ok {
 					// mimic the returned values from Synapse
 					res.Message = "You cannot reject this invite"
 					res.Code = 403
-					return nil, spec.LeaveServerNoticeError()
+					return nil, nil, spec.LeaveServerNoticeError()
 				}
 			}
 		}
@@ -149,22 +152,22 @@ func (r *Leaver) performLeaveRoomByID(
 	}
 	latestRes := api.QueryLatestEventsAndStateResponse{}
 	if err = helpers.QueryLatestEventsAndState(ctx, r.DB, r.RSAPI, &latestReq, &latestRes); err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 	if !latestRes.RoomExists {
-		return nil, fmt.Errorf("room %q does not exist", req.RoomID)
+		return nil, nil, fmt.Errorf("room %q does not exist", req.RoomID)
 	}
 
 	// Now let's see if the user is in the room.
 	if len(latestRes.StateEvents) == 0 {
-		return nil, fmt.Errorf("user %q is not a member of room %q", req.Leaver.String(), req.RoomID)
+		return nil, nil, fmt.Errorf("user %q is not a member of room %q", req.Leaver.String(), req.RoomID)
 	}
 	membership, err := latestRes.StateEvents[0].Membership()
 	if err != nil {
-		return nil, fmt.Errorf("error getting membership: %w", err)
+		return nil, nil, fmt.Errorf("error getting membership: %w", err)
 	}
 	if membership != spec.Join && membership != spec.Invite {
-		return nil, fmt.Errorf("user %q is not joined to the room (membership is %q)", req.Leaver.String(), membership)
+		return nil, nil, fmt.Errorf("user %q is not joined to the room (membership is %q)", req.Leaver.String(), membership)
 	}
 
 	// Prepare the template for the leave event.
@@ -177,10 +180,10 @@ func (r *Leaver) performLeaveRoomByID(
 		Redacts:  "",
 	}
 	if err = proto.SetContent(map[string]interface{}{"membership": "leave"}); err != nil {
-		return nil, fmt.Errorf("eb.SetContent: %w", err)
+		return nil, nil, fmt.Errorf("eb.SetContent: %w", err)
 	}
 	if err = proto.SetUnsigned(struct{}{}); err != nil {
-		return nil, fmt.Errorf("eb.SetUnsigned: %w", err)
+		return nil, nil, fmt.Errorf("eb.SetUnsigned: %w", err)
 	}
 
 	// We know that the user is in the room at this point so let's build
@@ -190,19 +193,29 @@ func (r *Leaver) performLeaveRoomByID(
 
 	validRoomID, err := spec.NewRoomID(req.RoomID)
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 
 	var buildRes rsAPI.QueryLatestEventsAndStateResponse
-	identity, err := r.RSAPI.SigningIdentityFor(ctx, *validRoomID, req.Leaver)
+	var identity fclient.SigningIdentity
+	if !cryptoIDs {
+		identity, err = r.RSAPI.SigningIdentityFor(ctx, *validRoomID, req.Leaver)
 		if err != nil {
-		return nil, fmt.Errorf("SigningIdentityFor: %w", err)
+			return nil, nil, fmt.Errorf("SigningIdentityFor: %w", err)
+		}
+	} else {
+		identity = fclient.SigningIdentity{
+			ServerName: spec.ServerName(*leaver),
+			KeyID:      "ed25519:1",
+			PrivateKey: nil,
+		}
 	}
 	event, err := eventutil.QueryAndBuildEvent(ctx, &proto, &identity, time.Now(), r.RSAPI, &buildRes)
 	if err != nil {
-		return nil, fmt.Errorf("eventutil.QueryAndBuildEvent: %w", err)
+		return nil, nil, fmt.Errorf("eventutil.QueryAndBuildEvent: %w", err)
 	}
 
+	if !cryptoIDs {
 		// Give our leave event to the roomserver input stream. The
 		// roomserver will process the membership change and notify
 		// downstream automatically.
@@ -219,10 +232,11 @@ func (r *Leaver) performLeaveRoomByID(
 		inputRes := api.InputRoomEventsResponse{}
 		r.Inputer.InputRoomEvents(ctx, &inputReq, &inputRes)
 		if err = inputRes.Err(); err != nil {
-		return nil, fmt.Errorf("r.InputRoomEvents: %w", err)
+			return nil, nil, fmt.Errorf("r.InputRoomEvents: %w", err)
+		}
 	}
 
-	return nil, nil
+	return nil, event, nil
 }
 
 func (r *Leaver) performFederatedRejectInvite(
@@ -231,7 +245,8 @@ func (r *Leaver) performFederatedRejectInvite(
 	res *api.PerformLeaveResponse, // nolint:unparam
 	inviteDomain spec.ServerName, eventID string,
 	leaver spec.SenderID,
-) ([]api.OutputEvent, error) {
+	cryptoIDs bool,
+) ([]api.OutputEvent, gomatrixserverlib.PDU, error) {
 	// Ask the federation sender to perform a federated leave for us.
 	leaveReq := fsAPI.PerformLeaveRequest{
 		RoomID:      req.RoomID,
@@ -239,7 +254,7 @@ func (r *Leaver) performFederatedRejectInvite(
 		ServerNames: []spec.ServerName{inviteDomain},
 	}
 	leaveRes := fsAPI.PerformLeaveResponse{}
-	if err := r.FSAPI.PerformLeave(ctx, &leaveReq, &leaveRes); err != nil {
+	if err := r.FSAPI.PerformLeave(ctx, &leaveReq, &leaveRes, cryptoIDs); err != nil {
 		// failures in PerformLeave should NEVER stop us from telling other components like the
 		// sync API that the invite was withdrawn. Otherwise we can end up with stuck invites.
 		util.GetLogger(ctx).WithError(err).Errorf("failed to PerformLeave, still retiring invite event")
@@ -279,5 +294,5 @@ func (r *Leaver) performFederatedRejectInvite(
 				TargetSenderID: leaver,
 			},
 		},
-	}, nil
+	}, nil, nil
 }

roomserver/internal/query/query.go

@@ -1044,7 +1044,7 @@ func (r *Queryer) QuerySenderIDForUser(ctx context.Context, roomID spec.RoomID,
 	}
 
 	switch version {
-	case gomatrixserverlib.RoomVersionPseudoIDs:
+	case gomatrixserverlib.RoomVersionPseudoIDs, gomatrixserverlib.RoomVersionCryptoIDs:
 		key, err := r.DB.SelectUserRoomPublicKey(ctx, userID, roomID)
 		if err != nil {
 			return nil, err

setup/config/config_roomserver.go

@@ -16,7 +16,8 @@ type RoomServer struct {
 }
 
 func (c *RoomServer) Defaults(opts DefaultOpts) {
-	c.DefaultRoomVersion = gomatrixserverlib.RoomVersionV10
+	//c.DefaultRoomVersion = gomatrixserverlib.RoomVersionV10
+	c.DefaultRoomVersion = gomatrixserverlib.RoomVersionCryptoIDs
 	if opts.Generate {
 		if !opts.SingleDatabase {
 			c.Database.ConnectionString = "file:roomserver.db"

syncapi/internal/keychange.go

@@ -46,6 +46,16 @@ func DeviceOTKCounts(ctx context.Context, keyAPI api.SyncKeyAPI, userID, deviceI
 	return nil
 }
 
+// OTCryptoIDCounts adds one-time pseudoID counts to the /sync response
+func OTCryptoIDCounts(ctx context.Context, keyAPI api.SyncKeyAPI, userID string, res *types.Response) error {
+	count, err := keyAPI.QueryOneTimeCryptoIDs(ctx, userID)
+	if err != nil {
+		return err
+	}
+	res.OTCryptoIDsCount = count.KeyCount
+	return nil
+}
+
 // DeviceListCatchup fills in the given response for the given user ID to bring it up-to-date with device lists. hasNew=true if the response
 // was filled in, else false if there are no new device list changes because there is nothing to catch up on. The response MUST
 // be already filled in with join/leave information.

syncapi/internal/keychange_test.go

@@ -50,7 +50,9 @@ func (k *mockKeyAPI) QueryKeyChanges(ctx context.Context, req *userapi.QueryKeyC
 }
 func (k *mockKeyAPI) QueryOneTimeKeys(ctx context.Context, req *userapi.QueryOneTimeKeysRequest, res *userapi.QueryOneTimeKeysResponse) error {
 	return nil
-
+}
+func (a *mockKeyAPI) QueryOneTimeCryptoIDs(ctx context.Context, userID string) (userapi.OneTimeCryptoIDsCount, *userapi.KeyError) {
+	return userapi.OneTimeCryptoIDsCount{}, nil
 }
 func (k *mockKeyAPI) QueryDeviceMessages(ctx context.Context, req *userapi.QueryDeviceMessagesRequest, res *userapi.QueryDeviceMessagesResponse) error {
 	return nil

syncapi/streams/stream_devicelist.go

@@ -38,7 +38,12 @@ func (p *DeviceListStreamProvider) IncrementalSync(
 	}
 	err = internal.DeviceOTKCounts(req.Context, p.userAPI, req.Device.UserID, req.Device.ID, req.Response)
 	if err != nil {
-		req.Log.WithError(err).Error("internal.DeviceListCatchup failed")
+		req.Log.WithError(err).Error("internal.DeviceOTKCounts failed")
+		return from
+	}
+	err = internal.OTCryptoIDCounts(req.Context, p.userAPI, req.Device.UserID, req.Response)
+	if err != nil {
+		req.Log.WithError(err).Error("internal.OTPseudoIDCounts failed")
 		return from
 	}
 

syncapi/sync/requestpool.go

@@ -280,6 +280,10 @@ func (rp *RequestPool) OnIncomingSyncRequest(req *http.Request, device *userapi.
 					if err != nil && err != context.Canceled {
 						syncReq.Log.WithError(err).Warn("failed to get OTK counts")
 					}
+					err = internal.OTCryptoIDCounts(syncReq.Context, rp.userAPI, syncReq.Device.UserID, syncReq.Response)
+					if err != nil && err != context.Canceled {
+						syncReq.Log.WithError(err).Warn("failed to get OTPseudoID counts")
+					}
 				}
 				return util.JSONResponse{
 					Code: http.StatusOK,

syncapi/syncapi_test.go

@@ -112,6 +112,10 @@ func (s *syncUserAPI) QueryOneTimeKeys(ctx context.Context, req *userapi.QueryOn
 	return nil
 }
 
+func (a *syncUserAPI) QueryOneTimeCryptoIDs(ctx context.Context, userID string) (userapi.OneTimeCryptoIDsCount, *userapi.KeyError) {
+	return userapi.OneTimeCryptoIDsCount{}, nil
+}
+
 func (s *syncUserAPI) PerformLastSeenUpdate(ctx context.Context, req *userapi.PerformLastSeenUpdateRequest, res *userapi.PerformLastSeenUpdateResponse) error {
 	return nil
 }

syncapi/synctypes/clientevent.go

@@ -153,7 +153,7 @@ func ToClientEvent(se gomatrixserverlib.PDU, format ClientEventFormat, userIDFor
 		// TODO: Set Signatures & Hashes fields
 	}
 
-	if format != FormatSyncFederation && se.Version() == gomatrixserverlib.RoomVersionPseudoIDs {
+	if format != FormatSyncFederation && (se.Version() == gomatrixserverlib.RoomVersionPseudoIDs || se.Version() == gomatrixserverlib.RoomVersionCryptoIDs) {
 		err := updatePseudoIDs(&ce, se, userIDForSender, format)
 		if err != nil {
 			return nil, err
@@ -304,7 +304,7 @@ func GetUpdatedInviteRoomState(userIDForSender spec.UserIDForSender, inviteRoomS
 		return nil, err
 	}
 
-	if event.Version() == gomatrixserverlib.RoomVersionPseudoIDs && eventFormat != FormatSyncFederation {
+	if (event.Version() == gomatrixserverlib.RoomVersionPseudoIDs || event.Version() == gomatrixserverlib.RoomVersionCryptoIDs) && eventFormat != FormatSyncFederation {
 		for i, ev := range inviteStateEvents {
 			userID, userIDErr := userIDForSender(roomID, spec.SenderID(ev.SenderID))
 			if userIDErr != nil {

syncapi/types/types.go

@@ -24,6 +24,7 @@ import (
 
 	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/gomatrixserverlib/spec"
+	"github.com/sirupsen/logrus"
 	"github.com/tidwall/gjson"
 
 	"github.com/matrix-org/dendrite/roomserver/api"
@@ -365,6 +366,7 @@ type Response struct {
 	ToDevice            *ToDeviceResponse `json:"to_device,omitempty"`
 	DeviceLists         *DeviceLists      `json:"device_lists,omitempty"`
 	DeviceListsOTKCount map[string]int    `json:"device_one_time_keys_count,omitempty"`
+	OTCryptoIDsCount    map[string]int    `json:"one_time_cryptoids_count,omitempty"`
 }
 
 func (r Response) MarshalJSON() ([]byte, error) {
@@ -427,6 +429,7 @@ func NewResponse() *Response {
 	res.DeviceLists = &DeviceLists{}
 	res.ToDevice = &ToDeviceResponse{}
 	res.DeviceListsOTKCount = map[string]int{}
+	res.OTCryptoIDsCount = map[string]int{}
 
 	return &res
 }
@@ -530,6 +533,7 @@ type InviteResponse struct {
 	InviteState struct {
 		Events []json.RawMessage `json:"events"`
 	} `json:"invite_state"`
+	OneTimeCryptoID string `json:"one_time_cryptoid,omitempty"`
 }
 
 // NewInviteResponse creates an empty response with initialised arrays.
@@ -537,11 +541,17 @@ func NewInviteResponse(ctx context.Context, rsAPI api.QuerySenderIDAPI, event *t
 	res := InviteResponse{}
 	res.InviteState.Events = []json.RawMessage{}
 
+	logrus.Infof("Room version: %s", event.Version())
+	if event.Version() == gomatrixserverlib.RoomVersionCryptoIDs {
+		logrus.Infof("Setting invite cryptoID to %s", *event.PDU.StateKey())
+		res.OneTimeCryptoID = *event.PDU.StateKey()
+	}
+
 	// First see if there's invite_room_state in the unsigned key of the invite.
 	// If there is then unmarshal it into the response. This will contain the
 	// partial room state such as join rules, room name etc.
 	if inviteRoomState := gjson.GetBytes(event.Unsigned(), "invite_room_state"); inviteRoomState.Exists() {
-		if event.Version() == gomatrixserverlib.RoomVersionPseudoIDs && eventFormat != synctypes.FormatSyncFederation {
+		if (event.Version() == gomatrixserverlib.RoomVersionPseudoIDs || event.Version() == gomatrixserverlib.RoomVersionCryptoIDs) && eventFormat != synctypes.FormatSyncFederation {
 			updatedInvite, err := synctypes.GetUpdatedInviteRoomState(func(roomID spec.RoomID, senderID spec.SenderID) (*spec.UserID, error) {
 				return rsAPI.QueryUserIDForSender(ctx, roomID, senderID)
 			}, inviteRoomState, event.PDU, event.RoomID(), eventFormat)

userapi/api/api.go

@@ -51,6 +51,7 @@ type AppserviceUserAPI interface {
 type RoomserverUserAPI interface {
 	QueryAccountData(ctx context.Context, req *QueryAccountDataRequest, res *QueryAccountDataResponse) error
 	QueryAccountByLocalpart(ctx context.Context, req *QueryAccountByLocalpartRequest, res *QueryAccountByLocalpartResponse) (err error)
+	ClaimOneTimeCryptoID(ctx context.Context, roomID spec.RoomID, userID spec.UserID) (spec.SenderID, error)
 }
 
 // api functions required by the media api
@@ -669,6 +670,7 @@ type UploadDeviceKeysAPI interface {
 type SyncKeyAPI interface {
 	QueryKeyChanges(ctx context.Context, req *QueryKeyChangesRequest, res *QueryKeyChangesResponse) error
 	QueryOneTimeKeys(ctx context.Context, req *QueryOneTimeKeysRequest, res *QueryOneTimeKeysResponse) error
+	QueryOneTimeCryptoIDs(ctx context.Context, userID string) (OneTimeCryptoIDsCount, *KeyError)
 	PerformMarkAsStaleIfNeeded(ctx context.Context, req *PerformMarkAsStaleRequest, res *struct{}) error
 }
 
@@ -772,12 +774,25 @@ type OneTimeKeys struct {
 	KeyJSON map[string]json.RawMessage
 }
 
+type OneTimeCryptoIDs struct {
+	// The user who owns this device
+	UserID string
+	// A map of algorithm:key_id => key JSON
+	KeyJSON map[string]json.RawMessage
+}
+
 // Split a key in KeyJSON into algorithm and key ID
 func (k *OneTimeKeys) Split(keyIDWithAlgo string) (algo string, keyID string) {
 	segments := strings.Split(keyIDWithAlgo, ":")
 	return segments[0], segments[1]
 }
 
+// Split a key in KeyJSON into algorithm and key ID
+func (k *OneTimeCryptoIDs) Split(keyIDWithAlgo string) (algo string, keyID string) {
+	segments := strings.Split(keyIDWithAlgo, ":")
+	return segments[0], segments[1]
+}
+
 // OneTimeKeysCount represents the counts of one-time keys for a single device
 type OneTimeKeysCount struct {
 	// The user who owns this device
@@ -792,12 +807,23 @@ type OneTimeKeysCount struct {
 	KeyCount map[string]int
 }
 
+type OneTimeCryptoIDsCount struct {
+	// The user who owns this device
+	UserID string
+	// algorithm to count e.g:
+	// {
+	//   "pseudoid_curve25519": 10,
+	// }
+	KeyCount map[string]int
+}
+
 // PerformUploadKeysRequest is the request to PerformUploadKeys
 type PerformUploadKeysRequest struct {
 	UserID           string // Required - User performing the request
 	DeviceID         string // Optional - Device performing the request, for fetching OTK count
 	DeviceKeys       []DeviceKeys
 	OneTimeKeys      []OneTimeKeys
+	OneTimeCryptoIDs []OneTimeCryptoIDs
 	// OnlyDisplayNameUpdates should be `true` if ALL the DeviceKeys are present to update
 	// the display name for their respective device, and NOT to modify the keys. The key
 	// itself doesn't change but it's easier to pretend upload new keys and reuse the same code paths.
@@ -812,6 +838,7 @@ type PerformUploadKeysResponse struct {
 	// A map of user_id -> device_id -> Error for tracking failures.
 	KeyErrors             map[string]map[string]*KeyError
 	OneTimeKeyCounts      []OneTimeKeysCount
+	OneTimeCryptoIDCounts []OneTimeCryptoIDsCount
 }
 
 // PerformDeleteKeysRequest asks the keyserver to forget about certain

userapi/consumers/roomserver.go

@@ -647,7 +647,7 @@ func (s *OutputRoomEventConsumer) notifyLocal(ctx context.Context, event *rstype
 func (s *OutputRoomEventConsumer) evaluatePushRules(ctx context.Context, event *rstypes.HeaderedEvent, mem *localMembership, roomSize int) ([]*pushrules.Action, error) {
 	user := ""
 	sender, err := s.rsAPI.QueryUserIDForSender(ctx, event.RoomID(), event.SenderID())
-	if err == nil {
+	if err == nil && sender != nil {
 		user = sender.String()
 	}
 	if user == mem.UserID {

userapi/internal/key_api.go

@@ -17,9 +17,11 @@ package internal
 import (
 	"bytes"
 	"context"
+	"crypto/ed25519"
 	"encoding/json"
 	"errors"
 	"fmt"
+	"strings"
 	"sync"
 	"time"
 
@@ -55,11 +57,21 @@ func (a *UserInternalAPI) PerformUploadKeys(ctx context.Context, req *api.Perfor
 	if len(req.OneTimeKeys) > 0 {
 		a.uploadOneTimeKeys(ctx, req, res)
 	}
+	if len(req.OneTimeCryptoIDs) > 0 {
+		a.uploadOneTimeCryptoIDs(ctx, req, res)
+	}
+	logrus.Infof("One time cryptoIDs count before: %v", res.OneTimeCryptoIDCounts)
 	otks, err := a.KeyDatabase.OneTimeKeysCount(ctx, req.UserID, req.DeviceID)
 	if err != nil {
 		return err
 	}
 	res.OneTimeKeyCounts = []api.OneTimeKeysCount{*otks}
+	otpIDs, err := a.KeyDatabase.OneTimeCryptoIDsCount(ctx, req.UserID)
+	if err != nil {
+		return err
+	}
+	res.OneTimeCryptoIDCounts = []api.OneTimeCryptoIDsCount{*otpIDs}
+	logrus.Infof("One time cryptoIDs count after: %v", res.OneTimeCryptoIDCounts)
 	return nil
 }
 
@@ -181,6 +193,17 @@ func (a *UserInternalAPI) QueryOneTimeKeys(ctx context.Context, req *api.QueryOn
 	return nil
 }
 
+func (a *UserInternalAPI) QueryOneTimeCryptoIDs(ctx context.Context, userID string) (api.OneTimeCryptoIDsCount, *api.KeyError) {
+	count, err := a.KeyDatabase.OneTimeCryptoIDsCount(ctx, userID)
+	if err != nil {
+		return api.OneTimeCryptoIDsCount{}, &api.KeyError{
+			Err: fmt.Sprintf("Failed to query OTID counts: %s", err),
+		}
+	}
+	return *count, nil
+
+}
+
 func (a *UserInternalAPI) QueryDeviceMessages(ctx context.Context, req *api.QueryDeviceMessagesRequest, res *api.QueryDeviceMessagesResponse) error {
 	msgs, err := a.KeyDatabase.DeviceKeysForUser(ctx, req.UserID, nil, false)
 	if err != nil {
@@ -773,6 +796,98 @@ func (a *UserInternalAPI) uploadOneTimeKeys(ctx context.Context, req *api.Perfor
 
 }
 
+func (a *UserInternalAPI) uploadOneTimeCryptoIDs(ctx context.Context, req *api.PerformUploadKeysRequest, res *api.PerformUploadKeysResponse) {
+	if req.UserID == "" {
+		res.Error = &api.KeyError{
+			Err: "user ID  missing",
+		}
+	}
+	if len(req.OneTimeCryptoIDs) == 0 {
+		counts, err := a.KeyDatabase.OneTimeCryptoIDsCount(ctx, req.UserID)
+		if err != nil {
+			res.Error = &api.KeyError{
+				Err: fmt.Sprintf("a.KeyDatabase.OneTimeCryptoIDsCount: %s", err),
+			}
+		}
+		if counts != nil {
+			logrus.Infof("Uploading one-time cryptoIDs: early result count: %v", *counts)
+			res.OneTimeCryptoIDCounts = append(res.OneTimeCryptoIDCounts, *counts)
+		}
+		return
+	}
+	for _, key := range req.OneTimeCryptoIDs {
+		// grab existing keys based on (user/algorithm/key ID)
+		keyIDsWithAlgorithms := make([]string, len(key.KeyJSON))
+		i := 0
+		for keyIDWithAlgo := range key.KeyJSON {
+			keyIDsWithAlgorithms[i] = keyIDWithAlgo
+			i++
+		}
+		existingKeys, err := a.KeyDatabase.ExistingOneTimeCryptoIDs(ctx, req.UserID, keyIDsWithAlgorithms)
+		if err != nil {
+			res.KeyError(req.UserID, req.DeviceID, &api.KeyError{
+				Err: "failed to query existing one-time cryptoIDs: " + err.Error(),
+			})
+			continue
+		}
+		for keyIDWithAlgo := range existingKeys {
+			// if keys exist and the JSON doesn't match, error out as the key already exists
+			if !bytes.Equal(existingKeys[keyIDWithAlgo], key.KeyJSON[keyIDWithAlgo]) {
+				res.KeyError(req.UserID, req.DeviceID, &api.KeyError{
+					Err: fmt.Sprintf("%s device %s: algorithm / key ID %s one-time cryptoID already exists", req.UserID, req.DeviceID, keyIDWithAlgo),
+				})
+				continue
+			}
+		}
+		// store one-time keys
+		counts, err := a.KeyDatabase.StoreOneTimeCryptoIDs(ctx, key)
+		if err != nil {
+			res.KeyError(req.UserID, req.DeviceID, &api.KeyError{
+				Err: fmt.Sprintf("%s device %s : failed to store one-time cryptoIDs: %s", req.UserID, req.DeviceID, err.Error()),
+			})
+			continue
+		}
+		// collect counts
+		logrus.Infof("Uploading one-time cryptoIDs: result count: %v", *counts)
+		res.OneTimeCryptoIDCounts = append(res.OneTimeCryptoIDCounts, *counts)
+	}
+}
+
+type Ed25519Key struct {
+	Key spec.Base64Bytes `json:"key"`
+}
+
+func (a *UserInternalAPI) ClaimOneTimeCryptoID(ctx context.Context, roomID spec.RoomID, userID spec.UserID) (spec.SenderID, error) {
+	cryptoID, err := a.KeyDatabase.ClaimOneTimeCryptoID(ctx, userID, "ed25519")
+	if err != nil {
+		return "", err
+	}
+
+	logrus.Infof("Claimed one time cryptoID: %s", cryptoID)
+
+	if cryptoID != nil {
+		for key, value := range cryptoID.KeyJSON {
+			keyParts := strings.Split(key, ":")
+			if keyParts[0] == "ed25519" {
+				var key_bytes Ed25519Key
+				err := json.Unmarshal(value, &key_bytes)
+				if err != nil {
+					return "", err
+				}
+
+				length := len(key_bytes.Key)
+				if length != ed25519.PublicKeySize {
+					return "", fmt.Errorf("Invalid ed25519 public key, %d is the wrong size", length)
+				}
+				// TODO: cryptoIDs - store senderID for this user here?
+				return spec.SenderID(key_bytes.Key.Encode()), nil
+			}
+		}
+	}
+
+	return "", fmt.Errorf("failed claiming a valid one time cryptoID for this user: %s", userID.String())
+}
+
 func emitDeviceKeyChanges(producer KeyChangeProducer, existing, new []api.DeviceMessage, onlyUpdateDisplayName bool) error {
 	// if we only want to update the display names, we can skip the checks below
 	if onlyUpdateDisplayName {

userapi/storage/interface.go

@@ -175,6 +175,11 @@ type KeyDatabase interface {
 	// OneTimeKeysCount returns a count of all OTKs for this device.
 	OneTimeKeysCount(ctx context.Context, userID, deviceID string) (*api.OneTimeKeysCount, error)
 
+	ExistingOneTimeCryptoIDs(ctx context.Context, userID string, keyIDsWithAlgorithms []string) (map[string]json.RawMessage, error)
+	StoreOneTimeCryptoIDs(ctx context.Context, keys api.OneTimeCryptoIDs) (*api.OneTimeCryptoIDsCount, error)
+	OneTimeCryptoIDsCount(ctx context.Context, userID string) (*api.OneTimeCryptoIDsCount, error)
+	ClaimOneTimeCryptoID(ctx context.Context, userID spec.UserID, algorithm string) (*api.OneTimeCryptoIDs, error)
+
 	// DeviceKeysJSON populates the KeyJSON for the given keys. If any proided `keys` have a `KeyJSON` or `StreamID` already then it will be replaced.
 	DeviceKeysJSON(ctx context.Context, keys []api.DeviceMessage) error
 

userapi/storage/postgres/one_time_cryptoids_table.go

@@ -0,0 +1,191 @@
+// 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.
+
+package postgres
+
+import (
+	"context"
+	"database/sql"
+	"encoding/json"
+	"time"
+
+	"github.com/lib/pq"
+	"github.com/matrix-org/dendrite/internal"
+	"github.com/matrix-org/dendrite/internal/sqlutil"
+	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/dendrite/userapi/storage/tables"
+)
+
+var oneTimeCryptoIDsSchema = `
+-- Stores one-time cryptoIDs for users
+CREATE TABLE IF NOT EXISTS keyserver_one_time_cryptoids (
+    user_id TEXT NOT NULL,
+	key_id TEXT NOT NULL,
+	algorithm TEXT NOT NULL,
+	ts_added_secs BIGINT NOT NULL,
+	key_json TEXT NOT NULL,
+	-- Clobber based on 3-uple of user/key/algorithm.
+    CONSTRAINT keyserver_one_time_cryptoids_unique UNIQUE (user_id, key_id, algorithm)
+);
+
+CREATE INDEX IF NOT EXISTS keyserver_one_time_cryptoids_idx ON keyserver_one_time_cryptoids (user_id);
+`
+
+const upsertCryptoIDsSQL = "" +
+	"INSERT INTO keyserver_one_time_cryptoids (user_id, key_id, algorithm, ts_added_secs, key_json)" +
+	" VALUES ($1, $2, $3, $4, $5)" +
+	" ON CONFLICT ON CONSTRAINT keyserver_one_time_cryptoids_unique" +
+	" DO UPDATE SET key_json = $5"
+
+const selectOneTimeCryptoIDsSQL = "" +
+	"SELECT concat(algorithm, ':', key_id) as algorithmwithid, key_json FROM keyserver_one_time_cryptoids WHERE user_id=$1 AND concat(algorithm, ':', key_id) = ANY($2);"
+
+const selectCryptoIDsCountSQL = "" +
+	"SELECT algorithm, COUNT(key_id) FROM " +
+	" (SELECT algorithm, key_id FROM keyserver_one_time_cryptoids WHERE user_id = $1 LIMIT 100)" +
+	" x GROUP BY algorithm"
+
+const deleteOneTimeCryptoIDSQL = "" +
+	"DELETE FROM keyserver_one_time_cryptoids WHERE user_id = $1 AND algorithm = $2 AND key_id = $3"
+
+const selectCryptoIDByAlgorithmSQL = "" +
+	"SELECT key_id, key_json FROM keyserver_one_time_cryptoids WHERE user_id = $1 AND algorithm = $2 LIMIT 1"
+
+const deleteOneTimeCryptoIDsSQL = "" +
+	"DELETE FROM keyserver_one_time_cryptoids WHERE user_id = $1"
+
+type oneTimeCryptoIDsStatements struct {
+	db                            *sql.DB
+	upsertCryptoIDsStmt           *sql.Stmt
+	selectCryptoIDsStmt           *sql.Stmt
+	selectCryptoIDsCountStmt      *sql.Stmt
+	selectCryptoIDByAlgorithmStmt *sql.Stmt
+	deleteOneTimeCryptoIDStmt     *sql.Stmt
+	deleteOneTimeCryptoIDsStmt    *sql.Stmt
+}
+
+func NewPostgresOneTimeCryptoIDsTable(db *sql.DB) (tables.OneTimeCryptoIDs, error) {
+	s := &oneTimeCryptoIDsStatements{
+		db: db,
+	}
+	_, err := db.Exec(oneTimeCryptoIDsSchema)
+	if err != nil {
+		return nil, err
+	}
+	return s, sqlutil.StatementList{
+		{&s.upsertCryptoIDsStmt, upsertCryptoIDsSQL},
+		{&s.selectCryptoIDsStmt, selectOneTimeCryptoIDsSQL},
+		{&s.selectCryptoIDsCountStmt, selectCryptoIDsCountSQL},
+		{&s.selectCryptoIDByAlgorithmStmt, selectCryptoIDByAlgorithmSQL},
+		{&s.deleteOneTimeCryptoIDStmt, deleteOneTimeCryptoIDSQL},
+		{&s.deleteOneTimeCryptoIDsStmt, deleteOneTimeCryptoIDsSQL},
+	}.Prepare(db)
+}
+
+func (s *oneTimeCryptoIDsStatements) SelectOneTimeCryptoIDs(ctx context.Context, userID string, keyIDsWithAlgorithms []string) (map[string]json.RawMessage, error) {
+	rows, err := s.selectCryptoIDsStmt.QueryContext(ctx, userID, pq.Array(keyIDsWithAlgorithms))
+	if err != nil {
+		return nil, err
+	}
+	defer internal.CloseAndLogIfError(ctx, rows, "selectCryptoIDsStmt: rows.close() failed")
+
+	result := make(map[string]json.RawMessage)
+	var (
+		algorithmWithID string
+		keyJSONStr      string
+	)
+	for rows.Next() {
+		if err := rows.Scan(&algorithmWithID, &keyJSONStr); err != nil {
+			return nil, err
+		}
+		result[algorithmWithID] = json.RawMessage(keyJSONStr)
+	}
+	return result, rows.Err()
+}
+
+func (s *oneTimeCryptoIDsStatements) CountOneTimeCryptoIDs(ctx context.Context, userID string) (*api.OneTimeCryptoIDsCount, error) {
+	counts := &api.OneTimeCryptoIDsCount{
+		UserID:   userID,
+		KeyCount: make(map[string]int),
+	}
+	rows, err := s.selectCryptoIDsCountStmt.QueryContext(ctx, userID)
+	if err != nil {
+		return nil, err
+	}
+	defer internal.CloseAndLogIfError(ctx, rows, "selectCryptoIDsCountStmt: rows.close() failed")
+	for rows.Next() {
+		var algorithm string
+		var count int
+		if err = rows.Scan(&algorithm, &count); err != nil {
+			return nil, err
+		}
+		counts.KeyCount[algorithm] = count
+	}
+	return counts, nil
+}
+
+func (s *oneTimeCryptoIDsStatements) InsertOneTimeCryptoIDs(ctx context.Context, txn *sql.Tx, keys api.OneTimeCryptoIDs) (*api.OneTimeCryptoIDsCount, error) {
+	now := time.Now().Unix()
+	counts := &api.OneTimeCryptoIDsCount{
+		UserID:   keys.UserID,
+		KeyCount: make(map[string]int),
+	}
+	for keyIDWithAlgo, keyJSON := range keys.KeyJSON {
+		algo, keyID := keys.Split(keyIDWithAlgo)
+		_, err := sqlutil.TxStmt(txn, s.upsertCryptoIDsStmt).ExecContext(
+			ctx, keys.UserID, keyID, algo, now, string(keyJSON),
+		)
+		if err != nil {
+			return nil, err
+		}
+	}
+	rows, err := sqlutil.TxStmt(txn, s.selectCryptoIDsCountStmt).QueryContext(ctx, keys.UserID)
+	if err != nil {
+		return nil, err
+	}
+	defer internal.CloseAndLogIfError(ctx, rows, "selectCryptoIDsCountStmt: rows.close() failed")
+	for rows.Next() {
+		var algorithm string
+		var count int
+		if err = rows.Scan(&algorithm, &count); err != nil {
+			return nil, err
+		}
+		counts.KeyCount[algorithm] = count
+	}
+
+	return counts, rows.Err()
+}
+
+func (s *oneTimeCryptoIDsStatements) SelectAndDeleteOneTimeCryptoID(
+	ctx context.Context, txn *sql.Tx, userID, algorithm string,
+) (map[string]json.RawMessage, error) {
+	var keyID string
+	var keyJSON string
+	err := sqlutil.TxStmtContext(ctx, txn, s.selectCryptoIDByAlgorithmStmt).QueryRowContext(ctx, userID, algorithm).Scan(&keyID, &keyJSON)
+	if err != nil {
+		if err == sql.ErrNoRows {
+			return nil, nil
+		}
+		return nil, err
+	}
+	_, err = sqlutil.TxStmtContext(ctx, txn, s.deleteOneTimeCryptoIDStmt).ExecContext(ctx, userID, algorithm, keyID)
+	return map[string]json.RawMessage{
+		algorithm + ":" + keyID: json.RawMessage(keyJSON),
+	}, err
+}
+
+func (s *oneTimeCryptoIDsStatements) DeleteOneTimeCryptoIDs(ctx context.Context, txn *sql.Tx, userID string) error {
+	_, err := sqlutil.TxStmt(txn, s.deleteOneTimeCryptoIDsStmt).ExecContext(ctx, userID)
+	return err
+}

userapi/storage/postgres/storage.go

@@ -149,6 +149,10 @@ func NewKeyDatabase(conMan *sqlutil.Connections, dbProperties *config.DatabaseOp
 	if err != nil {
 		return nil, err
 	}
+	otpid, err := NewPostgresOneTimeCryptoIDsTable(db)
+	if err != nil {
+		return nil, err
+	}
 	dk, err := NewPostgresDeviceKeysTable(db)
 	if err != nil {
 		return nil, err
@@ -172,6 +176,7 @@ func NewKeyDatabase(conMan *sqlutil.Connections, dbProperties *config.DatabaseOp
 
 	return &shared.KeyDatabase{
 		OneTimeKeysTable:      otk,
+		OneTimeCryptoIDsTable: otpid,
 		DeviceKeysTable:       dk,
 		KeyChangesTable:       kc,
 		StaleDeviceListsTable: sdl,

userapi/storage/shared/storage.go

@@ -65,6 +65,7 @@ type Database struct {
 
 type KeyDatabase struct {
 	OneTimeKeysTable      tables.OneTimeKeys
+	OneTimeCryptoIDsTable tables.OneTimeCryptoIDs
 	DeviceKeysTable       tables.DeviceKeys
 	KeyChangesTable       tables.KeyChanges
 	StaleDeviceListsTable tables.StaleDeviceLists
@@ -945,6 +946,40 @@ func (d *KeyDatabase) OneTimeKeysCount(ctx context.Context, userID, deviceID str
 	return d.OneTimeKeysTable.CountOneTimeKeys(ctx, userID, deviceID)
 }
 
+func (d *KeyDatabase) ExistingOneTimeCryptoIDs(ctx context.Context, userID string, keyIDsWithAlgorithms []string) (map[string]json.RawMessage, error) {
+	return d.OneTimeCryptoIDsTable.SelectOneTimeCryptoIDs(ctx, userID, keyIDsWithAlgorithms)
+}
+
+func (d *KeyDatabase) StoreOneTimeCryptoIDs(ctx context.Context, keys api.OneTimeCryptoIDs) (counts *api.OneTimeCryptoIDsCount, err error) {
+	_ = d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
+		counts, err = d.OneTimeCryptoIDsTable.InsertOneTimeCryptoIDs(ctx, txn, keys)
+		return err
+	})
+	return
+}
+
+func (d *KeyDatabase) OneTimeCryptoIDsCount(ctx context.Context, userID string) (*api.OneTimeCryptoIDsCount, error) {
+	return d.OneTimeCryptoIDsTable.CountOneTimeCryptoIDs(ctx, userID)
+}
+
+func (d *KeyDatabase) ClaimOneTimeCryptoID(ctx context.Context, userID spec.UserID, algorithm string) (*api.OneTimeCryptoIDs, error) {
+	var result *api.OneTimeCryptoIDs
+	err := d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
+		keyJSON, err := d.OneTimeCryptoIDsTable.SelectAndDeleteOneTimeCryptoID(ctx, txn, userID.String(), algorithm)
+		if err != nil {
+			return err
+		}
+		if keyJSON != nil {
+			result = &api.OneTimeCryptoIDs{
+				UserID:  userID.String(),
+				KeyJSON: keyJSON,
+			}
+		}
+		return nil
+	})
+	return result, err
+}
+
 func (d *KeyDatabase) DeviceKeysJSON(ctx context.Context, keys []api.DeviceMessage) error {
 	return d.DeviceKeysTable.SelectDeviceKeysJSON(ctx, keys)
 }

userapi/storage/sqlite3/one_time_cryptoids_table.go

@@ -0,0 +1,208 @@
+// 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.
+
+package sqlite3
+
+import (
+	"context"
+	"database/sql"
+	"encoding/json"
+	"time"
+
+	"github.com/matrix-org/dendrite/internal"
+	"github.com/matrix-org/dendrite/internal/sqlutil"
+	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/dendrite/userapi/storage/tables"
+	"github.com/sirupsen/logrus"
+)
+
+var oneTimeCryptoIDsSchema = `
+-- Stores one-time cryptoIDs for users
+CREATE TABLE IF NOT EXISTS keyserver_one_time_cryptoids (
+    user_id TEXT NOT NULL,
+	key_id TEXT NOT NULL,
+	algorithm TEXT NOT NULL,
+	ts_added_secs BIGINT NOT NULL,
+	key_json TEXT NOT NULL,
+	-- Clobber based on 3-uple of user/key/algorithm.
+    UNIQUE (user_id, key_id, algorithm)
+);
+
+CREATE INDEX IF NOT EXISTS keyserver_one_time_cryptoids_idx ON keyserver_one_time_cryptoids (user_id);
+`
+
+const upsertCryptoIDsSQL = "" +
+	"INSERT INTO keyserver_one_time_cryptoids (user_id, key_id, algorithm, ts_added_secs, key_json)" +
+	" VALUES ($1, $2, $3, $4, $5)" +
+	" ON CONFLICT (user_id, key_id, algorithm)" +
+	" DO UPDATE SET key_json = $5"
+
+const selectOneTimeCryptoIDsSQL = "" +
+	"SELECT key_id, algorithm, key_json FROM keyserver_one_time_cryptoids WHERE user_id=$1"
+
+const selectCryptoIDsCountSQL = "" +
+	"SELECT algorithm, COUNT(key_id) FROM " +
+	" (SELECT algorithm, key_id FROM keyserver_one_time_cryptoids WHERE user_id = $1 LIMIT 100)" +
+	" x GROUP BY algorithm"
+
+const deleteOneTimeCryptoIDSQL = "" +
+	"DELETE FROM keyserver_one_time_cryptoids WHERE user_id = $1 AND algorithm = $2 AND key_id = $3"
+
+const selectCryptoIDByAlgorithmSQL = "" +
+	"SELECT key_id, key_json FROM keyserver_one_time_cryptoids WHERE user_id = $1 AND algorithm = $2 LIMIT 1"
+
+const deleteOneTimeCryptoIDsSQL = "" +
+	"DELETE FROM keyserver_one_time_cryptoids WHERE user_id = $1"
+
+type oneTimeCryptoIDsStatements struct {
+	db                            *sql.DB
+	upsertCryptoIDsStmt           *sql.Stmt
+	selectCryptoIDsStmt           *sql.Stmt
+	selectCryptoIDsCountStmt      *sql.Stmt
+	selectCryptoIDByAlgorithmStmt *sql.Stmt
+	deleteOneTimeCryptoIDStmt     *sql.Stmt
+	deleteOneTimeCryptoIDsStmt    *sql.Stmt
+}
+
+func NewSqliteOneTimeCryptoIDsTable(db *sql.DB) (tables.OneTimeCryptoIDs, error) {
+	s := &oneTimeCryptoIDsStatements{
+		db: db,
+	}
+	_, err := db.Exec(oneTimeCryptoIDsSchema)
+	if err != nil {
+		return nil, err
+	}
+	return s, sqlutil.StatementList{
+		{&s.upsertCryptoIDsStmt, upsertCryptoIDsSQL},
+		{&s.selectCryptoIDsStmt, selectOneTimeCryptoIDsSQL},
+		{&s.selectCryptoIDsCountStmt, selectCryptoIDsCountSQL},
+		{&s.selectCryptoIDByAlgorithmStmt, selectCryptoIDByAlgorithmSQL},
+		{&s.deleteOneTimeCryptoIDStmt, deleteOneTimeCryptoIDSQL},
+		{&s.deleteOneTimeCryptoIDsStmt, deleteOneTimeCryptoIDsSQL},
+	}.Prepare(db)
+}
+
+func (s *oneTimeCryptoIDsStatements) SelectOneTimeCryptoIDs(ctx context.Context, userID string, keyIDsWithAlgorithms []string) (map[string]json.RawMessage, error) {
+	rows, err := s.selectCryptoIDsStmt.QueryContext(ctx, userID)
+	if err != nil {
+		return nil, err
+	}
+	defer internal.CloseAndLogIfError(ctx, rows, "selectCryptoIDsStmt: rows.close() failed")
+
+	wantSet := make(map[string]bool, len(keyIDsWithAlgorithms))
+	for _, ka := range keyIDsWithAlgorithms {
+		wantSet[ka] = true
+	}
+
+	result := make(map[string]json.RawMessage)
+	for rows.Next() {
+		var keyID string
+		var algorithm string
+		var keyJSONStr string
+		if err := rows.Scan(&keyID, &algorithm, &keyJSONStr); err != nil {
+			return nil, err
+		}
+		keyIDWithAlgo := algorithm + ":" + keyID
+		if wantSet[keyIDWithAlgo] {
+			result[keyIDWithAlgo] = json.RawMessage(keyJSONStr)
+		}
+	}
+	return result, rows.Err()
+}
+
+func (s *oneTimeCryptoIDsStatements) CountOneTimeCryptoIDs(ctx context.Context, userID string) (*api.OneTimeCryptoIDsCount, error) {
+	counts := &api.OneTimeCryptoIDsCount{
+		UserID:   userID,
+		KeyCount: make(map[string]int),
+	}
+	rows, err := s.selectCryptoIDsCountStmt.QueryContext(ctx, userID)
+	if err != nil {
+		return nil, err
+	}
+	defer internal.CloseAndLogIfError(ctx, rows, "selectCryptoIDsCountStmt: rows.close() failed")
+	for rows.Next() {
+		var algorithm string
+		var count int
+		if err = rows.Scan(&algorithm, &count); err != nil {
+			return nil, err
+		}
+		counts.KeyCount[algorithm] = count
+	}
+	return counts, nil
+}
+
+func (s *oneTimeCryptoIDsStatements) InsertOneTimeCryptoIDs(
+	ctx context.Context, txn *sql.Tx, keys api.OneTimeCryptoIDs,
+) (*api.OneTimeCryptoIDsCount, error) {
+	now := time.Now().Unix()
+	counts := &api.OneTimeCryptoIDsCount{
+		UserID:   keys.UserID,
+		KeyCount: make(map[string]int),
+	}
+	for keyIDWithAlgo, keyJSON := range keys.KeyJSON {
+		algo, keyID := keys.Split(keyIDWithAlgo)
+		_, err := sqlutil.TxStmt(txn, s.upsertCryptoIDsStmt).ExecContext(
+			ctx, keys.UserID, keyID, algo, now, string(keyJSON),
+		)
+		if err != nil {
+			return nil, err
+		}
+	}
+	rows, err := sqlutil.TxStmt(txn, s.selectCryptoIDsCountStmt).QueryContext(ctx, keys.UserID)
+	if err != nil {
+		return nil, err
+	}
+	defer internal.CloseAndLogIfError(ctx, rows, "selectCryptoIDsCountStmt: rows.close() failed")
+	for rows.Next() {
+		var algorithm string
+		var count int
+		if err = rows.Scan(&algorithm, &count); err != nil {
+			return nil, err
+		}
+		counts.KeyCount[algorithm] = count
+	}
+
+	return counts, rows.Err()
+}
+
+func (s *oneTimeCryptoIDsStatements) SelectAndDeleteOneTimeCryptoID(
+	ctx context.Context, txn *sql.Tx, userID, algorithm string,
+) (map[string]json.RawMessage, error) {
+	var keyID string
+	var keyJSON string
+	err := sqlutil.TxStmtContext(ctx, txn, s.selectCryptoIDByAlgorithmStmt).QueryRowContext(ctx, userID, algorithm).Scan(&keyID, &keyJSON)
+	if err != nil {
+		if err == sql.ErrNoRows {
+			logrus.Warnf("No rows found for one time cryptoIDs")
+			return nil, nil
+		}
+		return nil, err
+	}
+	_, err = sqlutil.TxStmtContext(ctx, txn, s.deleteOneTimeCryptoIDStmt).ExecContext(ctx, userID, algorithm, keyID)
+	if err != nil {
+		return nil, err
+	}
+	if keyJSON == "" {
+		logrus.Warnf("Empty key JSON for one time cryptoIDs")
+		return nil, nil
+	}
+	return map[string]json.RawMessage{
+		algorithm + ":" + keyID: json.RawMessage(keyJSON),
+	}, err
+}
+
+func (s *oneTimeCryptoIDsStatements) DeleteOneTimeCryptoIDs(ctx context.Context, txn *sql.Tx, userID string) error {
+	_, err := sqlutil.TxStmt(txn, s.deleteOneTimeCryptoIDsStmt).ExecContext(ctx, userID)
+	return err
+}

userapi/storage/sqlite3/storage.go

@@ -146,6 +146,10 @@ func NewKeyDatabase(conMan *sqlutil.Connections, dbProperties *config.DatabaseOp
 	if err != nil {
 		return nil, err
 	}
+	otpid, err := NewSqliteOneTimeCryptoIDsTable(db)
+	if err != nil {
+		return nil, err
+	}
 	dk, err := NewSqliteDeviceKeysTable(db)
 	if err != nil {
 		return nil, err
@@ -169,6 +173,7 @@ func NewKeyDatabase(conMan *sqlutil.Connections, dbProperties *config.DatabaseOp
 
 	return &shared.KeyDatabase{
 		OneTimeKeysTable:      otk,
+		OneTimeCryptoIDsTable: otpid,
 		DeviceKeysTable:       dk,
 		KeyChangesTable:       kc,
 		StaleDeviceListsTable: sdl,

userapi/storage/storage_test.go

@@ -1,6 +1,7 @@
 package storage_test
 
 import (
+	"bytes"
 	"context"
 	"encoding/json"
 	"fmt"
@@ -758,3 +759,35 @@ func TestDeviceKeysStreamIDGeneration(t *testing.T) {
 		}
 	})
 }
+
+func TestOneTimeCryptoIDs(t *testing.T) {
+	test.WithAllDatabases(t, func(t *testing.T, dbType test.DBType) {
+		db, clean := mustCreateKeyDatabase(t, dbType)
+		defer clean()
+		userID := "@alice:localhost"
+		otk := api.OneTimeCryptoIDs{
+			UserID:  userID,
+			KeyJSON: map[string]json.RawMessage{"pseudoid_curve25519:KEY1": []byte(`{"key":"v1"}`)},
+		}
+
+		// Add a one time pseudoID to the DB
+		_, err := db.StoreOneTimeCryptoIDs(ctx, otk)
+		MustNotError(t, err)
+
+		// Check the count of one time pseudoIDs is correct
+		count, err := db.OneTimeCryptoIDsCount(ctx, userID)
+		MustNotError(t, err)
+		if count.KeyCount["pseudoid_curve25519"] != 1 {
+			t.Fatalf("Expected 1 pseudoID, got %d", count.KeyCount["pseudoid_curve25519"])
+		}
+
+		// Check the actual pseudoid contents are correct
+		keysJSON, err := db.ExistingOneTimeCryptoIDs(ctx, userID, []string{"pseudoid_curve25519:KEY1"})
+		MustNotError(t, err)
+		keyJSON, err := keysJSON["pseudoid_curve25519:KEY1"].MarshalJSON()
+		MustNotError(t, err)
+		if !bytes.Equal(keyJSON, []byte(`{"key":"v1"}`)) {
+			t.Fatalf("Existing pseudoIDs do not match expected. Got %v", keysJSON["pseudoid_curve25519:KEY1"])
+		}
+	})
+}

userapi/storage/tables/interface.go

@@ -168,6 +168,14 @@ type OneTimeKeys interface {
 	DeleteOneTimeKeys(ctx context.Context, txn *sql.Tx, userID, deviceID string) error
 }
 
+type OneTimeCryptoIDs interface {
+	SelectOneTimeCryptoIDs(ctx context.Context, userID string, keyIDsWithAlgorithms []string) (map[string]json.RawMessage, error)
+	CountOneTimeCryptoIDs(ctx context.Context, userID string) (*api.OneTimeCryptoIDsCount, error)
+	InsertOneTimeCryptoIDs(ctx context.Context, txn *sql.Tx, keys api.OneTimeCryptoIDs) (*api.OneTimeCryptoIDsCount, error)
+	SelectAndDeleteOneTimeCryptoID(ctx context.Context, txn *sql.Tx, userID, algorithm string) (map[string]json.RawMessage, error)
+	DeleteOneTimeCryptoIDs(ctx context.Context, txn *sql.Tx, userID string) error
+}
+
 type DeviceKeys interface {
 	SelectDeviceKeysJSON(ctx context.Context, keys []api.DeviceMessage) error
 	InsertDeviceKeys(ctx context.Context, txn *sql.Tx, keys []api.DeviceMessage) error