snapshot of https://github.com/livekit/livekit.git @ 08c5433449c106943231037d0b892895f6e92d3b (2026-09-15)

pkg/rtc/participant_data_track.go

@@ -0,0 +1,212 @@
+// Copyright 2023 LiveKit, Inc.
+//
+// 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 rtc
+
+import (
+	"github.com/livekit/livekit-server/pkg/rtc/types"
+	"github.com/livekit/protocol/datatrack"
+	"github.com/livekit/protocol/livekit"
+	"github.com/livekit/protocol/logger"
+	"github.com/livekit/protocol/utils"
+	"github.com/livekit/protocol/utils/guid"
+)
+
+func (p *ParticipantImpl) HandlePublishDataTrackRequest(req *livekit.PublishDataTrackRequest) {
+	if !p.CanPublishData() || !p.params.EnableDataTracks {
+		p.pubLogger.Warnw("no permission to publish data track", nil, "req", logger.Proto(req))
+		p.sendRequestResponse(&livekit.RequestResponse{
+			Reason:  livekit.RequestResponse_NOT_ALLOWED,
+			Message: "does not have permission to publish data",
+			Request: &livekit.RequestResponse_PublishDataTrack{
+				PublishDataTrack: utils.CloneProto(req),
+			},
+		})
+		return
+	}
+
+	if req.PubHandle == 0 || req.PubHandle > 65535 {
+		p.pubLogger.Warnw("invalid data track handle", nil, "req", logger.Proto(req))
+		p.sendRequestResponse(&livekit.RequestResponse{
+			Reason:  livekit.RequestResponse_INVALID_HANDLE,
+			Message: "handle should be > 0 AND < 65536",
+			Request: &livekit.RequestResponse_PublishDataTrack{
+				PublishDataTrack: utils.CloneProto(req),
+			},
+		})
+		return
+	}
+
+	if len(req.Name) == 0 || len(req.Name) > 256 {
+		p.pubLogger.Warnw("invalid data track name", nil, "req", logger.Proto(req))
+		p.sendRequestResponse(&livekit.RequestResponse{
+			Reason:  livekit.RequestResponse_INVALID_NAME,
+			Message: "name should not be empty and should not exceed 256 characters",
+			Request: &livekit.RequestResponse_PublishDataTrack{
+				PublishDataTrack: utils.CloneProto(req),
+			},
+		})
+		return
+	}
+
+	if !p.params.LimitConfig.CheckDataTrackFrameEncoding(req.FrameEncoding) ||
+		!p.params.LimitConfig.CheckDataTrackSchemaID(req.Schema) {
+		p.pubLogger.Warnw("invalid encoding identifier", nil, "req", logger.Proto(req))
+		p.sendRequestResponse(&livekit.RequestResponse{
+			Reason:  livekit.RequestResponse_INVALID_REQUEST,
+			Message: "encoding identifier is empty or exceeds the maximum length",
+			Request: &livekit.RequestResponse_PublishDataTrack{
+				PublishDataTrack: utils.CloneProto(req),
+			},
+		})
+		return
+	}
+
+	publishedDataTracks := p.UpDataTrackManager.GetPublishedDataTracks()
+	for _, dt := range publishedDataTracks {
+		message := ""
+		reason := livekit.RequestResponse_OK
+		switch {
+		case dt.PubHandle() == uint16(req.PubHandle):
+			message = "a data track with same handle already exists"
+			reason = livekit.RequestResponse_DUPLICATE_HANDLE
+		case dt.Name() == req.Name:
+			message = "a data track with same name already exists"
+			reason = livekit.RequestResponse_DUPLICATE_NAME
+		}
+		if message != "" {
+			p.pubLogger.Warnw(
+				"cannot publish duplicate data track", nil,
+				"req", logger.Proto(req),
+				"existing", logger.Proto(dt.ToProto()),
+			)
+			p.sendRequestResponse(&livekit.RequestResponse{
+				Reason:  reason,
+				Message: message,
+				Request: &livekit.RequestResponse_PublishDataTrack{
+					PublishDataTrack: utils.CloneProto(req),
+				},
+			})
+			return
+		}
+	}
+
+	dti := &livekit.DataTrackInfo{
+		PubHandle:  req.PubHandle,
+		Sid:        guid.New(utils.DataTrackPrefix),
+		Name:       req.Name,
+		Encryption: req.Encryption,
+	}
+	dti.FrameEncoding = utils.CloneProto(req.GetFrameEncoding())
+	dti.Schema = utils.CloneProto(req.GetSchema())
+	dt := NewDataTrack(
+		DataTrackParams{
+			Logger:              p.params.Logger.WithValues("trackID", dti.Sid),
+			ParticipantID:       p.ID,
+			ParticipantIdentity: p.params.Identity,
+			BytesTrackStats: NewBytesTrackStats(
+				p.params.Country,
+				livekit.TrackID(dti.Sid),
+				p.ID(),
+				p.Kind(),
+				p.KindDetails(),
+				p.GetTelemetryListener,
+				p.params.Reporter,
+			),
+		},
+		dti,
+	)
+
+	p.UpDataTrackManager.AddPublishedDataTrack(dt)
+
+	p.sendPublishDataTrackResponse(dti)
+
+	p.setIsPublisher(true)
+	p.dirty.Store(true)
+}
+
+func (p *ParticipantImpl) HandleUnpublishDataTrackRequest(req *livekit.UnpublishDataTrackRequest) {
+	dt := p.UpDataTrackManager.GetPublishedDataTrack(uint16(req.PubHandle))
+	if dt == nil {
+		p.pubLogger.Warnw("unpublish data track not found", nil, "req", logger.Proto(req))
+		p.sendRequestResponse(&livekit.RequestResponse{
+			Reason: livekit.RequestResponse_NOT_FOUND,
+			Request: &livekit.RequestResponse_UnpublishDataTrack{
+				UnpublishDataTrack: utils.CloneProto(req),
+			},
+		})
+		return
+	}
+
+	p.UpDataTrackManager.RemovePublishedDataTrack(dt)
+
+	p.sendUnpublishDataTrackResponse(dt.ToProto())
+
+	p.dirty.Store(true)
+}
+
+func (p *ParticipantImpl) HandleUpdateDataSubscription(req *livekit.UpdateDataSubscription) {
+	p.listener().OnUpdateDataSubscriptions(p, req)
+}
+
+func (p *ParticipantImpl) onReceivedDataTrackMessage(data []byte, arrivalTime int64) {
+	var packet datatrack.Packet
+	if err := packet.Unmarshal(data); err != nil {
+		p.params.Logger.Errorw("could not unmarshal data track message", err)
+		return
+	}
+
+	p.UpDataTrackManager.HandleReceivedDataTrackMessage(data, &packet, arrivalTime)
+
+	p.listener().OnDataTrackMessage(p, data, &packet)
+}
+
+// wraps the promoted UpTrackManager.UpdateSubscriptionPermission to also revoke
+// data track subscriptions that are no longer permitted
+func (p *ParticipantImpl) UpdateSubscriptionPermission(
+	subscriptionPermission *livekit.SubscriptionPermission,
+	timedVersion utils.TimedVersion,
+	resolverBySid func(participantID livekit.ParticipantID) types.LocalParticipant,
+) error {
+	if err := p.UpTrackManager.UpdateSubscriptionPermission(subscriptionPermission, timedVersion, resolverBySid); err != nil {
+		return err
+	}
+
+	p.maybeRevokeDataTrackSubscriptions()
+	return nil
+}
+
+func (p *ParticipantImpl) maybeRevokeDataTrackSubscriptions() {
+	for _, dt := range p.UpDataTrackManager.GetPublishedDataTracks() {
+		allowed := p.UpTrackManager.GetAllowedSubscribers(dt.ID())
+		if allowed == nil {
+			// no restrictions
+			continue
+		}
+
+		dt.RevokeDisallowedSubscribers(allowed)
+	}
+}
+
+func (p *ParticipantImpl) GetNextSubscribedDataTrackHandle() uint16 {
+	p.lock.Lock()
+	defer p.lock.Unlock()
+
+	p.nextSubscribedDataTrackHandle++
+	if p.nextSubscribedDataTrackHandle == 0 {
+		p.nextSubscribedDataTrackHandle++
+	}
+
+	return p.nextSubscribedDataTrackHandle
+}