implement rtcp receiver reports; fix #22

Makefile

@@ -65,10 +65,18 @@ endef
 export DOCKERFILE_RUN
 
 define CONFIG_RUN
+#rtspPort: 8555
+#rtpPort: 8002
+#rtcpPort: 8003
+
 paths:
   all:
     readUser: test
     readPass: tast
+
+  proxied:
+    source: rtsp://192.168.10.1/unicast
+    sourceProtocol: udp
 endef
 export CONFIG_RUN
 

conf.yml

@@ -1,20 +1,20 @@
 
 # supported stream protocols (the handshake is always performed with TCP)
 protocols: [udp, tcp]
-# port of the TCP rtsp listener
+# port of the TCP RTSP listener
 rtspPort: 8554
-# port of the UDP rtp listener
+# port of the UDP RTP listener
 rtpPort: 8000
-# port of the UDP rtcp listener
+# port of the UDP RTCP listener
 rtcpPort: 8001
-# timeout of read operations
-readTimeout: 5s
-# timeout of write operations
-writeTimeout: 5s
 # script to run when a client connects
 preScript:
 # script to run when a client disconnects
 postScript:
+# timeout of read operations
+readTimeout: 5s
+# timeout of write operations
+writeTimeout: 5s
 # enable pprof on port 9999 to monitor performance
 pprof: false
 

go.mod

@@ -6,7 +6,8 @@ require (
 	github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751 // indirect
 	github.com/alecthomas/units v0.0.0-20190924025748-f65c72e2690d // indirect
 	github.com/aler9/gortsplib v0.0.0-20200710091324-fb7d7b008e68
-	github.com/stretchr/testify v1.4.0
+	github.com/pion/rtcp v1.2.3
+	github.com/stretchr/testify v1.5.1
 	gopkg.in/alecthomas/kingpin.v2 v2.2.6
 	gopkg.in/yaml.v2 v2.2.2
 	gortc.io/sdp v0.18.2

go.sum

@@ -6,6 +6,8 @@ github.com/aler9/gortsplib v0.0.0-20200710091324-fb7d7b008e68 h1:apyYugiG/luHl0X
 github.com/aler9/gortsplib v0.0.0-20200710091324-fb7d7b008e68/go.mod h1:sL64nUkmrTVhlT/GCaxRXyI2Xk7m8XSdw5Uv8xKGPdc=
 github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/pion/rtcp v1.2.3 h1:2wrhKnqgSz91Q5nzYTO07mQXztYPtxL8a0XOss4rJqA=
+github.com/pion/rtcp v1.2.3/go.mod h1:zGhIv0RPRF0Z1Wiij22pUt5W/c9fevqSzT4jje/oK7I=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
@@ -13,6 +15,8 @@ github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZN
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
+github.com/stretchr/testify v1.5.1 h1:nOGnQDM7FYENwehXlg/kFVnos3rEvtKTjRvOWSzb6H4=
+github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
 gopkg.in/alecthomas/kingpin.v2 v2.2.6 h1:jMFz6MfLP0/4fUyZle81rXUoxOBFi19VUFKVDOQfozc=
 gopkg.in/alecthomas/kingpin.v2 v2.2.6/go.mod h1:FMv+mEhP44yOT+4EoQTLFTRgOQ1FBLkstjWtayDeSgw=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=

main.go

@@ -11,6 +11,7 @@ import (
 	"regexp"
 	"time"
 
+	"github.com/aler9/gortsplib"
 	"gopkg.in/alecthomas/kingpin.v2"
 	"gopkg.in/yaml.v2"
 	"gortc.io/sdp"
@@ -223,9 +224,9 @@ type publisher interface {
 type program struct {
 	conf           *conf
 	protocols      map[streamProtocol]struct{}
-	tcpl           *serverTcpListener
-	udplRtp        *serverUdpListener
-	udplRtcp       *serverUdpListener
+	rtspl          *serverTcpListener
+	rtpl           *serverUdpListener
+	rtcpl          *serverUdpListener
 	clients        map[*serverClient]struct{}
 	streamers      []*streamer
 	publishers     map[string]publisher
@@ -387,24 +388,24 @@ func newProgram(sargs []string, stdin io.Reader) (*program, error) {
 		http.DefaultServeMux = http.NewServeMux()
 	}
 
-	p.udplRtp, err = newServerUdpListener(p, conf.RtpPort, _TRACK_FLOW_TYPE_RTP)
+	p.rtpl, err = newServerUdpListener(p, conf.RtpPort, _TRACK_FLOW_TYPE_RTP)
 	if err != nil {
 		return nil, err
 	}
 
-	p.udplRtcp, err = newServerUdpListener(p, conf.RtcpPort, _TRACK_FLOW_TYPE_RTCP)
+	p.rtcpl, err = newServerUdpListener(p, conf.RtcpPort, _TRACK_FLOW_TYPE_RTCP)
 	if err != nil {
 		return nil, err
 	}
 
-	p.tcpl, err = newServerTcpListener(p)
+	p.rtspl, err = newServerTcpListener(p)
 	if err != nil {
 		return nil, err
 	}
 
-	go p.udplRtp.run()
-	go p.udplRtcp.run()
-	go p.tcpl.run()
+	go p.rtpl.run()
+	go p.rtcpl.run()
+	go p.rtspl.run()
 	for _, s := range p.streamers {
 		go s.run()
 	}
@@ -548,7 +549,7 @@ outer:
 				continue
 			}
 
-			client.udpLastFrameTime = time.Now()
+			client.rtcpReceivers[trackId].onFrame(evt.trackFlowType, evt.buf)
 			p.forwardFrame(client.path, trackId, evt.trackFlowType, evt.buf)
 
 		case programEventClientFrameTcp:
@@ -613,9 +614,9 @@ outer:
 		s.close()
 	}
 
-	p.tcpl.close()
-	p.udplRtcp.close()
-	p.udplRtp.close()
+	p.rtspl.close()
+	p.rtcpl.close()
+	p.rtpl.close()
 
 	for c := range p.clients {
 		c.close()
@@ -659,31 +660,42 @@ func (p *program) findPublisher(addr *net.UDPAddr, trackFlowType trackFlowType)
 }
 
 func (p *program) forwardFrame(path string, trackId int, trackFlowType trackFlowType, frame []byte) {
-	for c := range p.clients {
-		if c.path == path && c.state == _CLIENT_STATE_PLAY {
-			if c.streamProtocol == _STREAM_PROTOCOL_UDP {
+	for client := range p.clients {
+		if client.path == path && client.state == _CLIENT_STATE_PLAY {
+			if client.streamProtocol == _STREAM_PROTOCOL_UDP {
 				if trackFlowType == _TRACK_FLOW_TYPE_RTP {
-					p.udplRtp.write(&udpAddrBufPair{
+					p.rtpl.write(&udpAddrBufPair{
 						addr: &net.UDPAddr{
-							IP:   c.ip(),
-							Zone: c.zone(),
-							Port: c.streamTracks[trackId].rtpPort,
+							IP:   client.ip(),
+							Zone: client.zone(),
+							Port: client.streamTracks[trackId].rtpPort,
 						},
 						buf: frame,
 					})
 				} else {
-					p.udplRtcp.write(&udpAddrBufPair{
+					p.rtcpl.write(&udpAddrBufPair{
 						addr: &net.UDPAddr{
-							IP:   c.ip(),
-							Zone: c.zone(),
-							Port: c.streamTracks[trackId].rtcpPort,
+							IP:   client.ip(),
+							Zone: client.zone(),
+							Port: client.streamTracks[trackId].rtcpPort,
 						},
 						buf: frame,
 					})
 				}
 
 			} else {
-				c.writeFrame(trackFlowTypeToInterleavedChannel(trackId, trackFlowType), frame)
+				channel := trackFlowTypeToInterleavedChannel(trackId, trackFlowType)
+
+				buf := client.writeBuf.swap()
+				buf = buf[:len(frame)]
+				copy(buf, frame)
+
+				client.events <- serverClientEventFrameTcp{
+					frame: &gortsplib.InterleavedFrame{
+						Channel: channel,
+						Content: buf,
+					},
+				}
 			}
 		}
 	}

server-client.go

@@ -14,10 +14,21 @@ import (
 )
 
 const (
-	_UDP_CHECK_STREAM_INTERVAL = 5 * time.Second
-	_UDP_STREAM_DEAD_AFTER     = 10 * time.Second
+	_CLIENT_CHECK_STREAM_INTERVAL    = 5 * time.Second
+	_CLIENT_STREAM_DEAD_AFTER        = 15 * time.Second
+	_CLIENT_RECEIVER_REPORT_INTERVAL = 10 * time.Second
 )
 
+type serverClientEvent interface {
+	isServerClientEvent()
+}
+
+type serverClientEventFrameTcp struct {
+	frame *gortsplib.InterleavedFrame
+}
+
+func (serverClientEventFrameTcp) isServerClientEvent() {}
+
 type serverClientState int
 
 const (
@@ -65,11 +76,11 @@ type serverClient struct {
 	streamSdpParsed *sdp.Message // only if publisher
 	streamProtocol  streamProtocol
 	streamTracks    []*track
-	udpLastFrameTime time.Time
+	rtcpReceivers   []*rtcpReceiver
 	readBuf         *doubleBuffer
 	writeBuf        *doubleBuffer
 
-	writeChan chan *gortsplib.InterleavedFrame // only if state = _CLIENT_STATE_PLAY
+	events chan serverClientEvent
 	done   chan struct{}
 }
 
@@ -201,31 +212,45 @@ outer:
 
 func (c *serverClient) runPlay() bool {
 	if c.streamProtocol == _STREAM_PROTOCOL_TCP {
-		writeDone := make(chan struct{})
+		readDone := make(chan error)
 		go func() {
-			defer close(writeDone)
-			for frame := range c.writeChan {
-				c.conn.WriteInterleavedFrame(frame)
-			}
-		}()
-
 			buf := make([]byte, 2048)
 			for {
 				_, err := c.conn.NetConn().Read(buf)
 				if err != nil {
+					readDone <- err
+					break
+				}
+			}
+		}()
+
+	outer:
+		for {
+			select {
+			case err := <-readDone:
 				if err != io.EOF {
 					c.log("ERR: %s", err)
 				}
-				break
+				break outer
+
+			case rawEvt := <-c.events:
+				switch evt := rawEvt.(type) {
+				case serverClientEventFrameTcp:
+					c.conn.WriteInterleavedFrame(evt.frame)
+				}
+			}
 		}
+
+		go func() {
+			for range c.events {
 			}
+		}()
 
 		done := make(chan struct{})
 		c.p.events <- programEventClientClose{done, c}
 		<-done
 
-		close(c.writeChan)
-		<-writeDone
+		close(c.events)
 
 	} else {
 		for {
@@ -255,27 +280,27 @@ func (c *serverClient) runRecord() bool {
 	if c.streamProtocol == _STREAM_PROTOCOL_TCP {
 		frame := &gortsplib.InterleavedFrame{}
 
-	outer:
+		readDone := make(chan error)
+		go func() {
 			for {
 				frame.Content = c.readBuf.swap()
 				frame.Content = frame.Content[:cap(frame.Content)]
 				recv, err := c.conn.ReadInterleavedFrameOrRequest(frame)
 				if err != nil {
-				if err != io.EOF {
-					c.log("ERR: %s", err)
-				}
-				break outer
+					readDone <- err
+					break
 				}
 
 				switch recvt := recv.(type) {
 				case *gortsplib.InterleavedFrame:
 					trackId, trackFlowType := interleavedChannelToTrackFlowType(frame.Channel)
-
 					if trackId >= len(c.streamTracks) {
 						c.log("ERR: invalid track id '%d'", trackId)
-					break outer
+						readDone <- nil
+						break
 					}
 
+					c.rtcpReceivers[trackId].onFrame(trackFlowType, frame.Content)
 					c.p.events <- programEventClientFrameTcp{
 						c.path,
 						trackId,
@@ -286,52 +311,116 @@ func (c *serverClient) runRecord() bool {
 				case *gortsplib.Request:
 					err := c.handleRequest(recvt)
 					if err != nil {
-					break outer
+						readDone <- nil
+						break
 					}
 				}
 			}
+		}()
 
-		done := make(chan struct{})
-		c.p.events <- programEventClientClose{done, c}
-		<-done
+		checkStreamTicker := time.NewTicker(_CLIENT_CHECK_STREAM_INTERVAL)
+		receiverReportTicker := time.NewTicker(_CLIENT_RECEIVER_REPORT_INTERVAL)
 
-	} else {
-		c.udpLastFrameTime = time.Now()
+	outer1:
+		for {
+			select {
+			case err := <-readDone:
+				if err != nil && err != io.EOF {
+					c.log("ERR: %s", err)
+				}
+				break outer1
 
-		udpCheckStreamTicker := time.NewTicker(_UDP_CHECK_STREAM_INTERVAL)
-		udpCheckStreamDone := make(chan struct{})
-		go func() {
-			defer close(udpCheckStreamDone)
-			for range udpCheckStreamTicker.C {
-				if time.Since(c.udpLastFrameTime) >= _UDP_STREAM_DEAD_AFTER {
+			case <-checkStreamTicker.C:
+				for trackId := range c.streamTracks {
+					if time.Since(c.rtcpReceivers[trackId].lastFrameTime()) >= _CLIENT_STREAM_DEAD_AFTER {
 						c.log("ERR: stream is dead")
 						c.conn.NetConn().Close()
-					break
+						<-readDone
+						break outer1
 					}
 				}
-		}()
 
+			case <-receiverReportTicker.C:
+				for trackId := range c.streamTracks {
+					channel := trackFlowTypeToInterleavedChannel(trackId, _TRACK_FLOW_TYPE_RTCP)
+
+					frame := c.rtcpReceivers[trackId].report()
+					c.conn.WriteInterleavedFrame(&gortsplib.InterleavedFrame{
+						Channel: channel,
+						Content: frame,
+					})
+				}
+			}
+		}
+
+		checkStreamTicker.Stop()
+		receiverReportTicker.Stop()
+
+	} else {
+		readDone := make(chan error)
+		go func() {
 			for {
 				req, err := c.conn.ReadRequest()
 				if err != nil {
-				if err != io.EOF {
-					c.log("ERR: %s", err)
-				}
+					readDone <- err
 					break
 				}
 
 				err = c.handleRequest(req)
 				if err != nil {
+					readDone <- nil // err is not needed
 					break
 				}
 			}
+		}()
+
+		checkStreamTicker := time.NewTicker(_CLIENT_CHECK_STREAM_INTERVAL)
+		receiverReportTicker := time.NewTicker(_CLIENT_RECEIVER_REPORT_INTERVAL)
+
+	outer2:
+		for {
+			select {
+			case err := <-readDone:
+				if err != nil && err != io.EOF {
+					c.log("ERR: %s", err)
+				}
+				break outer2
+
+			case <-checkStreamTicker.C:
+				for trackId := range c.streamTracks {
+					if time.Since(c.rtcpReceivers[trackId].lastFrameTime()) >= _CLIENT_STREAM_DEAD_AFTER {
+						c.log("ERR: stream is dead")
+						c.conn.NetConn().Close()
+						<-readDone
+						break outer2
+					}
+				}
+
+			case <-receiverReportTicker.C:
+				for trackId := range c.streamTracks {
+					frame := c.rtcpReceivers[trackId].report()
+					c.p.rtcpl.writeChan <- &udpAddrBufPair{
+						addr: &net.UDPAddr{
+							IP:   c.ip(),
+							Zone: c.zone(),
+							Port: c.streamTracks[trackId].rtcpPort,
+						},
+						buf: frame,
+					}
+				}
+			}
+		}
+
+		checkStreamTicker.Stop()
+		receiverReportTicker.Stop()
+	}
 
 	done := make(chan struct{})
 	c.p.events <- programEventClientClose{done, c}
 	<-done
 
-		udpCheckStreamTicker.Stop()
-		<-udpCheckStreamDone
+	for trackId := range c.streamTracks {
+		c.rtcpReceivers[trackId].close()
 	}
 
 	return false
@@ -342,17 +431,6 @@ func (c *serverClient) close() {
 	<-c.done
 }
 
-func (c *serverClient) writeFrame(channel uint8, inbuf []byte) {
-	buf := c.writeBuf.swap()
-	buf = buf[:len(inbuf)]
-	copy(buf, inbuf)
-
-	c.writeChan <- &gortsplib.InterleavedFrame{
-		Channel: channel,
-		Content: buf,
-	}
-}
-
 func (c *serverClient) writeResError(req *gortsplib.Request, code gortsplib.StatusCode, err error) {
 	c.log("ERR: %s", err)
 
@@ -532,7 +610,7 @@ func (c *serverClient) handleRequest(req *gortsplib.Request) error {
 		c.p.events <- programEventClientDescribe{path, res}
 		sdp := <-res
 		if sdp == nil {
-			c.writeResError(req, gortsplib.StatusBadRequest, fmt.Errorf("no one is streaming on path '%s'", path))
+			c.writeResError(req, gortsplib.StatusNotFound, fmt.Errorf("no one is publishing on path '%s'", path))
 			return errClientTerminate
 		}
 
@@ -906,8 +984,10 @@ func (c *serverClient) handleRequest(req *gortsplib.Request) error {
 			},
 		})
 
+		if c.streamProtocol == _STREAM_PROTOCOL_TCP {
 			c.writeBuf = newDoubleBuffer(2048)
-		c.writeChan = make(chan *gortsplib.InterleavedFrame)
+			c.events = make(chan serverClientEvent)
+		}
 
 		// set state
 		res = make(chan error)
@@ -948,6 +1028,11 @@ func (c *serverClient) handleRequest(req *gortsplib.Request) error {
 			},
 		})
 
+		c.rtcpReceivers = make([]*rtcpReceiver, len(c.streamTracks))
+		for trackId := range c.streamTracks {
+			c.rtcpReceivers[trackId] = newRtcpReceiver()
+		}
+
 		res := make(chan error)
 		c.p.events <- programEventClientRecord{res, c}
 		<-res

server-udpl.go

@@ -54,7 +54,9 @@ func (l *serverUdpListener) log(format string, args ...interface{}) {
 }
 
 func (l *serverUdpListener) run() {
+	writeDone := make(chan struct{})
 	go func() {
+		defer close(writeDone)
 		for w := range l.writeChan {
 			l.nconn.SetWriteDeadline(time.Now().Add(l.p.conf.WriteTimeout))
 			l.nconn.WriteTo(w.buf, w.addr)
@@ -76,6 +78,7 @@ func (l *serverUdpListener) run() {
 	}
 
 	close(l.writeChan)
+	<-writeDone
 
 	close(l.done)
 }

streamer-udpl.go

@@ -16,6 +16,7 @@ type streamerUdpListener struct {
 	running       bool
 	readBuf       *doubleBuffer
 
+	writeChan chan *udpAddrBufPair
 	done      chan struct{}
 }
 
@@ -36,6 +37,7 @@ func newStreamerUdpListener(p *program, port int, streamer *streamer,
 		publisherIp:   publisherIp,
 		nconn:         nconn,
 		readBuf:       newDoubleBuffer(2048),
+		writeChan:     make(chan *udpAddrBufPair),
 		done:          make(chan struct{}),
 	}
 
@@ -43,19 +45,28 @@ func newStreamerUdpListener(p *program, port int, streamer *streamer,
 }
 
 func (l *streamerUdpListener) close() {
-	l.nconn.Close()
-
-	if l.running {
-		<-l.done
-	}
+	l.nconn.Close() // close twice
 }
 
 func (l *streamerUdpListener) start() {
-	l.running = true
 	go l.run()
 }
 
+func (l *streamerUdpListener) stop() {
+	l.nconn.Close()
+	<-l.done
+}
+
 func (l *streamerUdpListener) run() {
+	writeDone := make(chan struct{})
+	go func() {
+		defer close(writeDone)
+		for w := range l.writeChan {
+			l.nconn.SetWriteDeadline(time.Now().Add(l.p.conf.WriteTimeout))
+			l.nconn.WriteTo(w.buf, w.addr)
+		}
+	}()
+
 	for {
 		buf := l.readBuf.swap()
 		n, addr, err := l.nconn.ReadFromUDP(buf)
@@ -67,10 +78,12 @@ func (l *streamerUdpListener) run() {
 			continue
 		}
 
-		l.streamer.udpLastFrameTime = time.Now()
-
+		l.streamer.rtcpReceivers[l.trackId].onFrame(l.trackFlowType, buf[:n])
 		l.p.events <- programEventStreamerFrame{l.streamer, l.trackId, l.trackFlowType, buf[:n]}
 	}
 
+	close(l.writeChan)
+	<-writeDone
+
 	close(l.done)
 }

streamer.go

@@ -14,16 +14,16 @@ import (
 )
 
 const (
-	_DIAL_TIMEOUT          = 10 * time.Second
-	_RETRY_INTERVAL        = 5 * time.Second
-	_CHECK_STREAM_INTERVAL = 6 * time.Second
-	_STREAM_DEAD_AFTER     = 5 * time.Second
-	_KEEPALIVE_INTERVAL    = 60 * time.Second
+	_STREAMER_RETRY_INTERVAL           = 5 * time.Second
+	_STREAMER_CHECK_STREAM_INTERVAL    = 5 * time.Second
+	_STREAMER_STREAM_DEAD_AFTER        = 15 * time.Second
+	_STREAMER_KEEPALIVE_INTERVAL       = 60 * time.Second
+	_STREAMER_RECEIVER_REPORT_INTERVAL = 10 * time.Second
 )
 
 type streamerUdpListenerPair struct {
-	udplRtp  *streamerUdpListener
-	udplRtcp *streamerUdpListener
+	rtpl  *streamerUdpListener
+	rtcpl *streamerUdpListener
 }
 
 type streamer struct {
@@ -35,8 +35,7 @@ type streamer struct {
 	clientSdpParsed *sdp.Message
 	serverSdpText   []byte
 	serverSdpParsed *sdp.Message
-	firstTime        bool
-	udpLastFrameTime time.Time
+	rtcpReceivers   []*rtcpReceiver
 	readBuf         *doubleBuffer
 
 	terminate chan struct{}
@@ -82,7 +81,6 @@ func newStreamer(p *program, path string, source string, sourceProtocol string)
 		path:      path,
 		ur:        ur,
 		proto:     proto,
-		firstTime: true,
 		readBuf:   newDoubleBuffer(512 * 1024),
 		terminate: make(chan struct{}),
 		done:      make(chan struct{}),
@@ -113,30 +111,26 @@ func (s *streamer) run() {
 		if !ok {
 			break
 		}
-	}
 
-	close(s.done)
-}
-
-func (s *streamer) do() bool {
-	if s.firstTime {
-		s.firstTime = false
-	} else {
-		t := time.NewTimer(_RETRY_INTERVAL)
+		t := time.NewTimer(_STREAMER_RETRY_INTERVAL)
 		select {
 		case <-s.terminate:
-			return false
+			break
 		case <-t.C:
 		}
 	}
 
+	close(s.done)
+}
+
+func (s *streamer) do() bool {
 	s.log("initializing with protocol %s", s.proto)
 
 	var nconn net.Conn
 	var err error
 	dialDone := make(chan struct{})
 	go func() {
-		nconn, err = net.DialTimeout("tcp", s.ur.Host, _DIAL_TIMEOUT)
+		nconn, err = net.DialTimeout("tcp", s.ur.Host, s.p.conf.ReadTimeout)
 		close(dialDone)
 	}()
 
@@ -251,16 +245,16 @@ func (s *streamer) runUdp(conn *gortsplib.ConnClient) bool {
 
 	defer func() {
 		for _, pair := range streamerUdpListenerPairs {
-			pair.udplRtp.close()
-			pair.udplRtcp.close()
+			pair.rtpl.close()
+			pair.rtcpl.close()
 		}
 	}()
 
 	for i, media := range s.clientSdpParsed.Medias {
 		var rtpPort int
 		var rtcpPort int
-		var udplRtp *streamerUdpListener
-		var udplRtcp *streamerUdpListener
+		var rtpl *streamerUdpListener
+		var rtcpl *streamerUdpListener
 		func() {
 			for {
 				// choose two consecutive ports in range 65536-10000
@@ -269,16 +263,16 @@ func (s *streamer) runUdp(conn *gortsplib.ConnClient) bool {
 				rtcpPort = rtpPort + 1
 
 				var err error
-				udplRtp, err = newStreamerUdpListener(s.p, rtpPort, s, i,
+				rtpl, err = newStreamerUdpListener(s.p, rtpPort, s, i,
 					_TRACK_FLOW_TYPE_RTP, publisherIp)
 				if err != nil {
 					continue
 				}
 
-				udplRtcp, err = newStreamerUdpListener(s.p, rtcpPort, s, i,
+				rtcpl, err = newStreamerUdpListener(s.p, rtcpPort, s, i,
 					_TRACK_FLOW_TYPE_RTCP, publisherIp)
 				if err != nil {
-					udplRtp.close()
+					rtpl.close()
 					continue
 				}
 
@@ -338,23 +332,23 @@ func (s *streamer) runUdp(conn *gortsplib.ConnClient) bool {
 		})
 		if err != nil {
 			s.log("ERR: %s", err)
-			udplRtp.close()
-			udplRtcp.close()
+			rtpl.close()
+			rtcpl.close()
 			return true
 		}
 
 		if res.StatusCode != gortsplib.StatusOK {
 			s.log("ERR: SETUP returned code %d (%s)", res.StatusCode, res.StatusMessage)
-			udplRtp.close()
-			udplRtcp.close()
+			rtpl.close()
+			rtcpl.close()
 			return true
 		}
 
 		tsRaw, ok := res.Header["Transport"]
 		if !ok || len(tsRaw) != 1 {
 			s.log("ERR: transport header not provided")
-			udplRtp.close()
-			udplRtcp.close()
+			rtpl.close()
+			rtcpl.close()
 			return true
 		}
 
@@ -362,17 +356,17 @@ func (s *streamer) runUdp(conn *gortsplib.ConnClient) bool {
 		rtpServerPort, rtcpServerPort := th.GetPorts("server_port")
 		if rtpServerPort == 0 {
 			s.log("ERR: server ports not provided")
-			udplRtp.close()
-			udplRtcp.close()
+			rtpl.close()
+			rtcpl.close()
 			return true
 		}
 
-		udplRtp.publisherPort = rtpServerPort
-		udplRtcp.publisherPort = rtcpServerPort
+		rtpl.publisherPort = rtpServerPort
+		rtcpl.publisherPort = rtcpServerPort
 
 		streamerUdpListenerPairs = append(streamerUdpListenerPairs, streamerUdpListenerPair{
-			udplRtp:  udplRtp,
-			udplRtcp: udplRtcp,
+			rtpl:  rtpl,
+			rtcpl: rtcpl,
 		})
 	}
 
@@ -395,30 +389,32 @@ func (s *streamer) runUdp(conn *gortsplib.ConnClient) bool {
 		return true
 	}
 
-	for _, pair := range streamerUdpListenerPairs {
-		pair.udplRtp.start()
-		pair.udplRtcp.start()
+	s.rtcpReceivers = make([]*rtcpReceiver, len(s.clientSdpParsed.Medias))
+	for trackId := range s.clientSdpParsed.Medias {
+		s.rtcpReceivers[trackId] = newRtcpReceiver()
 	}
 
-	tickerSendKeepalive := time.NewTicker(_KEEPALIVE_INTERVAL)
-	defer tickerSendKeepalive.Stop()
+	for _, pair := range streamerUdpListenerPairs {
+		pair.rtpl.start()
+		pair.rtcpl.start()
+	}
 
-	s.udpLastFrameTime = time.Now()
-	tickerCheckStream := time.NewTicker(_CHECK_STREAM_INTERVAL)
-	defer tickerCheckStream.Stop()
+	sendKeepaliveTicker := time.NewTicker(_STREAMER_KEEPALIVE_INTERVAL)
+	checkStreamTicker := time.NewTicker(_STREAMER_CHECK_STREAM_INTERVAL)
+	receiverReportTicker := time.NewTicker(_STREAMER_RECEIVER_REPORT_INTERVAL)
 
 	s.p.events <- programEventStreamerReady{s}
 
-	defer func() {
-		s.p.events <- programEventStreamerNotReady{s}
-	}()
+	var ret bool
 
+outer:
 	for {
 		select {
 		case <-s.terminate:
-			return false
+			ret = false
+			break outer
 
-		case <-tickerSendKeepalive.C:
+		case <-sendKeepaliveTicker.C:
 			_, err = conn.WriteRequest(&gortsplib.Request{
 				Method: gortsplib.OPTIONS,
 				Url: &url.URL{
@@ -429,18 +425,52 @@ func (s *streamer) runUdp(conn *gortsplib.ConnClient) bool {
 			})
 			if err != nil {
 				s.log("ERR: %s", err)
-				return true
+				ret = true
+				break outer
 			}
 
-		case <-tickerCheckStream.C:
-			if time.Since(s.udpLastFrameTime) >= _STREAM_DEAD_AFTER {
+		case <-checkStreamTicker.C:
+			for trackId := range s.clientSdpParsed.Medias {
+				if time.Since(s.rtcpReceivers[trackId].lastFrameTime()) >= _STREAMER_STREAM_DEAD_AFTER {
 					s.log("ERR: stream is dead")
-				return true
+					ret = true
+					break outer
+				}
+			}
+
+		case <-receiverReportTicker.C:
+			for trackId := range s.clientSdpParsed.Medias {
+				frame := s.rtcpReceivers[trackId].report()
+				streamerUdpListenerPairs[trackId].rtcpl.writeChan <- &udpAddrBufPair{
+					addr: &net.UDPAddr{
+						IP:   conn.NetConn().RemoteAddr().(*net.TCPAddr).IP,
+						Zone: conn.NetConn().RemoteAddr().(*net.TCPAddr).Zone,
+						Port: streamerUdpListenerPairs[trackId].rtcpl.publisherPort,
+					},
+					buf: frame,
 				}
 			}
 		}
 	}
 
+	sendKeepaliveTicker.Stop()
+	checkStreamTicker.Stop()
+	receiverReportTicker.Stop()
+
+	s.p.events <- programEventStreamerNotReady{s}
+
+	for _, pair := range streamerUdpListenerPairs {
+		pair.rtpl.stop()
+		pair.rtcpl.stop()
+	}
+
+	for trackId := range s.clientSdpParsed.Medias {
+		s.rtcpReceivers[trackId].close()
+	}
+
+	return ret
+}
+
 func (s *streamer) runTcp(conn *gortsplib.ConnClient) bool {
 	for i, media := range s.clientSdpParsed.Medias {
 		interleaved := fmt.Sprintf("interleaved=%d-%d", (i * 2), (i*2)+1)
@@ -536,7 +566,7 @@ func (s *streamer) runTcp(conn *gortsplib.ConnClient) bool {
 
 	frame := &gortsplib.InterleavedFrame{}
 
-outer:
+outer1:
 	for {
 		frame.Content = s.readBuf.swap()
 		frame.Content = frame.Content[:cap(frame.Content)]
@@ -553,18 +583,19 @@ outer:
 				s.log("ERR: PLAY returned code %d (%s)", recvt.StatusCode, recvt.StatusMessage)
 				return true
 			}
-			break outer
+			break outer1
 
 		case *gortsplib.InterleavedFrame:
 			// ignore the frames sent before the response
 		}
 	}
 
-	s.p.events <- programEventStreamerReady{s}
+	s.rtcpReceivers = make([]*rtcpReceiver, len(s.clientSdpParsed.Medias))
+	for trackId := range s.clientSdpParsed.Medias {
+		s.rtcpReceivers[trackId] = newRtcpReceiver()
+	}
 
-	defer func() {
-		s.p.events <- programEventStreamerNotReady{s}
-	}()
+	s.p.events <- programEventStreamerReady{s}
 
 	chanConnError := make(chan struct{})
 	go func() {
@@ -580,18 +611,62 @@ outer:
 
 			trackId, trackFlowType := interleavedChannelToTrackFlowType(frame.Channel)
 
+			s.rtcpReceivers[trackId].onFrame(trackFlowType, frame.Content)
 			s.p.events <- programEventStreamerFrame{s, trackId, trackFlowType, frame.Content}
 		}
 	}()
 
+	checkStreamTicker := time.NewTicker(_STREAMER_CHECK_STREAM_INTERVAL)
+	receiverReportTicker := time.NewTicker(_STREAMER_RECEIVER_REPORT_INTERVAL)
+
+	var ret bool
+
+outer2:
+	for {
 		select {
 		case <-s.terminate:
-		return false
+			ret = false
+			break outer2
+
 		case <-chanConnError:
-		return true
+			ret = true
+			break outer2
+
+		case <-checkStreamTicker.C:
+			for trackId := range s.clientSdpParsed.Medias {
+				if time.Since(s.rtcpReceivers[trackId].lastFrameTime()) >= _STREAMER_STREAM_DEAD_AFTER {
+					s.log("ERR: stream is dead")
+					ret = true
+					break outer2
+				}
+			}
+
+		case <-receiverReportTicker.C:
+			for trackId := range s.clientSdpParsed.Medias {
+				frame := s.rtcpReceivers[trackId].report()
+
+				channel := trackFlowTypeToInterleavedChannel(trackId, _TRACK_FLOW_TYPE_RTCP)
+
+				conn.WriteInterleavedFrame(&gortsplib.InterleavedFrame{
+					Channel: channel,
+					Content: frame,
+				})
+			}
 		}
 	}
 
+	checkStreamTicker.Stop()
+	receiverReportTicker.Stop()
+
+	s.p.events <- programEventStreamerNotReady{s}
+
+	for trackId := range s.clientSdpParsed.Medias {
+		s.rtcpReceivers[trackId].close()
+	}
+
+	return ret
+}
+
 func (s *streamer) close() {
 	close(s.terminate)
 	<-s.done

utils.go

@@ -2,7 +2,11 @@ package main
 
 import (
 	"fmt"
+	"math/rand"
 	"net"
+	"time"
+
+	"github.com/pion/rtcp"
 )
 
 func parseIpCidrList(in []string) ([]interface{}, error) {
@@ -90,3 +94,139 @@ func (db *doubleBuffer) swap() []byte {
 	db.curBuf = !db.curBuf
 	return ret
 }
+
+type rtcpReceiverEvent interface {
+	isRtpReceiverEvent()
+}
+
+type rtcpReceiverEventFrameRtp struct {
+	sequenceNumber uint16
+}
+
+func (rtcpReceiverEventFrameRtp) isRtpReceiverEvent() {}
+
+type rtcpReceiverEventFrameRtcp struct {
+	ssrc          uint32
+	ntpTimeMiddle uint32
+}
+
+func (rtcpReceiverEventFrameRtcp) isRtpReceiverEvent() {}
+
+type rtcpReceiverEventLastFrameTime struct {
+	res chan time.Time
+}
+
+func (rtcpReceiverEventLastFrameTime) isRtpReceiverEvent() {}
+
+type rtcpReceiverEventReport struct {
+	res chan []byte
+}
+
+func (rtcpReceiverEventReport) isRtpReceiverEvent() {}
+
+type rtcpReceiverEventTerminate struct{}
+
+func (rtcpReceiverEventTerminate) isRtpReceiverEvent() {}
+
+type rtcpReceiver struct {
+	events chan rtcpReceiverEvent
+	done   chan struct{}
+}
+
+func newRtcpReceiver() *rtcpReceiver {
+	rr := &rtcpReceiver{
+		events: make(chan rtcpReceiverEvent),
+		done:   make(chan struct{}),
+	}
+	go rr.run()
+	return rr
+}
+
+func (rr *rtcpReceiver) run() {
+	lastFrameTime := time.Now()
+	publisherSSRC := uint32(0)
+	receiverSSRC := rand.Uint32()
+	sequenceNumberCycles := uint16(0)
+	lastSequenceNumber := uint16(0)
+	lastSenderReport := uint32(0)
+
+outer:
+	for rawEvt := range rr.events {
+		switch evt := rawEvt.(type) {
+		case rtcpReceiverEventFrameRtp:
+			if evt.sequenceNumber < lastSequenceNumber {
+				sequenceNumberCycles += 1
+			}
+			lastSequenceNumber = evt.sequenceNumber
+			lastFrameTime = time.Now()
+
+		case rtcpReceiverEventFrameRtcp:
+			publisherSSRC = evt.ssrc
+			lastSenderReport = evt.ntpTimeMiddle
+
+		case rtcpReceiverEventLastFrameTime:
+			evt.res <- lastFrameTime
+
+		case rtcpReceiverEventReport:
+			rr := &rtcp.ReceiverReport{
+				SSRC: receiverSSRC,
+				Reports: []rtcp.ReceptionReport{
+					{
+						SSRC:               publisherSSRC,
+						LastSequenceNumber: uint32(sequenceNumberCycles)<<8 | uint32(lastSequenceNumber),
+						LastSenderReport:   lastSenderReport,
+					},
+				},
+			}
+			frame, _ := rr.Marshal()
+			evt.res <- frame
+
+		case rtcpReceiverEventTerminate:
+			break outer
+		}
+	}
+
+	close(rr.events)
+
+	close(rr.done)
+}
+
+func (rr *rtcpReceiver) close() {
+	rr.events <- rtcpReceiverEventTerminate{}
+	<-rr.done
+}
+
+func (rr *rtcpReceiver) onFrame(trackFlowType trackFlowType, buf []byte) {
+	if trackFlowType == _TRACK_FLOW_TYPE_RTP {
+		// extract sequence number of first frame
+		if len(buf) >= 3 {
+			sequenceNumber := uint16(uint16(buf[2])<<8 | uint16(buf[1]))
+			rr.events <- rtcpReceiverEventFrameRtp{sequenceNumber}
+		}
+
+	} else {
+		frames, err := rtcp.Unmarshal(buf)
+		if err == nil {
+			for _, frame := range frames {
+				if senderReport, ok := (frame).(*rtcp.SenderReport); ok {
+					rr.events <- rtcpReceiverEventFrameRtcp{
+						senderReport.SSRC,
+						uint32(senderReport.NTPTime >> 16),
+					}
+				}
+			}
+		}
+	}
+}
+
+func (rr *rtcpReceiver) lastFrameTime() time.Time {
+	res := make(chan time.Time)
+	rr.events <- rtcpReceiverEventLastFrameTime{res}
+	return <-res
+}
+
+func (rr *rtcpReceiver) report() []byte {
+	res := make(chan []byte)
+	rr.events <- rtcpReceiverEventReport{res}
+	return <-res
+}