Files
livekit/pkg/rtc/config.go
2022-11-23 16:01:36 +08:00

402 lines
10 KiB
Go

package rtc
import (
"errors"
"fmt"
"net"
"time"
"github.com/pion/ice/v2"
"github.com/pion/sdp/v3"
"github.com/pion/webrtc/v3"
"github.com/livekit/livekit-server/pkg/config"
logging "github.com/livekit/livekit-server/pkg/logger"
"github.com/livekit/livekit-server/pkg/sfu/buffer"
dd "github.com/livekit/livekit-server/pkg/sfu/dependencydescriptor"
"github.com/livekit/protocol/logger"
)
const (
minUDPBufferSize = 5_000_000
defaultUDPBufferSize = 16_777_216
frameMarking = "urn:ietf:params:rtp-hdrext:framemarking"
)
type WebRTCConfig struct {
Configuration webrtc.Configuration
SettingEngine webrtc.SettingEngine
Receiver ReceiverConfig
BufferFactory *buffer.Factory
UDPMux ice.UDPMux
TCPMuxListener *net.TCPListener
Publisher DirectionConfig
Subscriber DirectionConfig
}
type ReceiverConfig struct {
PacketBufferSize int
}
type RTPHeaderExtensionConfig struct {
Audio []string
Video []string
}
type RTCPFeedbackConfig struct {
Audio []webrtc.RTCPFeedback
Video []webrtc.RTCPFeedback
}
type DirectionConfig struct {
RTPHeaderExtension RTPHeaderExtensionConfig
RTCPFeedback RTCPFeedbackConfig
}
const (
// number of packets to buffer up
readBufferSize = 50
writeBufferSizeInBytes = 4 * 1024 * 1024
)
func NewWebRTCConfig(conf *config.Config, externalIP string) (*WebRTCConfig, error) {
rtcConf := conf.RTC
c := webrtc.Configuration{
SDPSemantics: webrtc.SDPSemanticsUnifiedPlan,
}
s := webrtc.SettingEngine{
LoggerFactory: logging.NewLoggerFactory(logger.GetLogger()),
}
if len(rtcConf.Interfaces.Includes) != 0 || len(rtcConf.Interfaces.Excludes) != 0 {
s.SetInterfaceFilter(InterfaceFilterFromConf(rtcConf.Interfaces))
}
var ipFilter func(net.IP) bool
if len(rtcConf.IPs.Includes) != 0 || len(rtcConf.IPs.Excludes) != 0 {
filter, err := IPFilterFromConf(rtcConf.IPs)
if err != nil {
return nil, err
}
ipFilter = filter
s.SetIPFilter(filter)
}
// force it to the node IPs that the user has set
if externalIP != "" && (conf.RTC.UseExternalIP || (conf.RTC.NodeIP != "" && !conf.RTC.NodeIPAutoGenerated)) {
if conf.RTC.UseExternalIP {
ips, err := getNAT1to1IPsForConf(conf, ipFilter)
if err != nil {
return nil, err
}
logger.Debugw("using external IPs", "ips", ips)
s.SetNAT1To1IPs(ips, webrtc.ICECandidateTypeHost)
} else {
s.SetNAT1To1IPs([]string{externalIP}, webrtc.ICECandidateTypeHost)
}
}
if rtcConf.PacketBufferSize == 0 {
rtcConf.PacketBufferSize = 500
}
var udpMux ice.UDPMux
var err error
networkTypes := make([]webrtc.NetworkType, 0, 4)
if !rtcConf.ForceTCP {
networkTypes = append(networkTypes,
webrtc.NetworkTypeUDP4, webrtc.NetworkTypeUDP6,
)
if rtcConf.ICEPortRangeStart != 0 && rtcConf.ICEPortRangeEnd != 0 {
if err := s.SetEphemeralUDPPortRange(uint16(rtcConf.ICEPortRangeStart), uint16(rtcConf.ICEPortRangeEnd)); err != nil {
return nil, err
}
} else if rtcConf.UDPPort != 0 {
opts := []ice.UDPMuxFromPortOption{
ice.UDPMuxFromPortWithReadBufferSize(defaultUDPBufferSize),
ice.UDPMuxFromPortWithWriteBufferSize(defaultUDPBufferSize),
ice.UDPMuxFromPortWithLogger(s.LoggerFactory.NewLogger("udp_mux")),
}
if rtcConf.EnableLoopbackCandidate {
opts = append(opts, ice.UDPMuxFromPortWithLoopback())
}
udpMux, err := ice.NewMultiUDPMuxFromPort(int(rtcConf.UDPPort), opts...)
if err != nil {
return nil, err
}
s.SetICEUDPMux(udpMux)
if !conf.Development {
checkUDPReadBuffer()
}
}
}
// use TCP mux when it's set
var tcpListener *net.TCPListener
if rtcConf.TCPPort != 0 {
networkTypes = append(networkTypes,
webrtc.NetworkTypeTCP4, webrtc.NetworkTypeTCP6,
)
tcpListener, err = net.ListenTCP("tcp", &net.TCPAddr{
Port: int(rtcConf.TCPPort),
})
if err != nil {
return nil, err
}
tcpMux := ice.NewTCPMuxDefault(ice.TCPMuxParams{
Logger: s.LoggerFactory.NewLogger("tcp_mux"),
Listener: tcpListener,
ReadBufferSize: readBufferSize,
WriteBufferSize: writeBufferSizeInBytes,
})
s.SetICETCPMux(tcpMux)
}
if len(networkTypes) == 0 {
return nil, errors.New("TCP is forced but not configured")
}
s.SetNetworkTypes(networkTypes)
if rtcConf.EnableLoopbackCandidate {
s.SetIncludeLoopbackCandidate(true)
}
// publisher configuration
publisherConfig := DirectionConfig{
RTPHeaderExtension: RTPHeaderExtensionConfig{
Audio: []string{
sdp.SDESMidURI,
sdp.SDESRTPStreamIDURI,
sdp.AudioLevelURI,
},
Video: []string{
sdp.SDESMidURI,
sdp.SDESRTPStreamIDURI,
sdp.TransportCCURI,
frameMarking,
dd.ExtensionUrl,
},
},
RTCPFeedback: RTCPFeedbackConfig{
Video: []webrtc.RTCPFeedback{
{Type: webrtc.TypeRTCPFBTransportCC},
{Type: webrtc.TypeRTCPFBCCM, Parameter: "fir"},
{Type: webrtc.TypeRTCPFBNACK},
{Type: webrtc.TypeRTCPFBNACK, Parameter: "pli"},
},
},
}
// subscriber configuration
subscriberConfig := DirectionConfig{
RTPHeaderExtension: RTPHeaderExtensionConfig{
Video: []string{dd.ExtensionUrl},
},
RTCPFeedback: RTCPFeedbackConfig{
Video: []webrtc.RTCPFeedback{
{Type: webrtc.TypeRTCPFBCCM, Parameter: "fir"},
{Type: webrtc.TypeRTCPFBNACK},
{Type: webrtc.TypeRTCPFBNACK, Parameter: "pli"},
},
},
}
if rtcConf.CongestionControl.UseSendSideBWE {
subscriberConfig.RTPHeaderExtension.Video = append(subscriberConfig.RTPHeaderExtension.Video, sdp.TransportCCURI)
subscriberConfig.RTCPFeedback.Video = append(subscriberConfig.RTCPFeedback.Video, webrtc.RTCPFeedback{Type: webrtc.TypeRTCPFBTransportCC})
} else {
subscriberConfig.RTPHeaderExtension.Video = append(subscriberConfig.RTPHeaderExtension.Video, sdp.ABSSendTimeURI)
subscriberConfig.RTCPFeedback.Video = append(subscriberConfig.RTCPFeedback.Video, webrtc.RTCPFeedback{Type: webrtc.TypeRTCPFBGoogREMB})
}
if rtcConf.UseICELite {
s.SetLite(true)
} else if rtcConf.NodeIP == "" && !rtcConf.UseExternalIP {
// use STUN servers for server to support NAT
// when deployed in production, we expect UseExternalIP to be used, and ports accessible
// this is not compatible with ICE Lite
// Do not automatically add STUN servers if nodeIP is set
if len(rtcConf.STUNServers) > 0 {
c.ICEServers = []webrtc.ICEServer{iceServerForStunServers(rtcConf.STUNServers)}
} else {
c.ICEServers = []webrtc.ICEServer{iceServerForStunServers(config.DefaultStunServers)}
}
}
return &WebRTCConfig{
Configuration: c,
SettingEngine: s,
Receiver: ReceiverConfig{
PacketBufferSize: rtcConf.PacketBufferSize,
},
UDPMux: udpMux,
TCPMuxListener: tcpListener,
Publisher: publisherConfig,
Subscriber: subscriberConfig,
}, nil
}
func (c *WebRTCConfig) SetBufferFactory(factory *buffer.Factory) {
c.BufferFactory = factory
c.SettingEngine.BufferFactory = factory.GetOrNew
}
func iceServerForStunServers(servers []string) webrtc.ICEServer {
iceServer := webrtc.ICEServer{}
for _, stunServer := range servers {
iceServer.URLs = append(iceServer.URLs, fmt.Sprintf("stun:%s", stunServer))
}
return iceServer
}
func getNAT1to1IPsForConf(conf *config.Config, ipFilter func(net.IP) bool) ([]string, error) {
stunServers := conf.RTC.STUNServers
if len(stunServers) == 0 {
stunServers = config.DefaultStunServers
}
localIPs, err := config.GetLocalIPAddresses(conf.RTC.EnableLoopbackCandidate)
if err != nil {
return nil, err
}
type ipmapping struct {
externalIP string
localIP string
}
addrCh := make(chan ipmapping, len(localIPs))
for _, ip := range localIPs {
if ipFilter != nil && !ipFilter(net.ParseIP(ip)) {
continue
}
go func(localIP string) {
addr, err := config.GetExternalIP(stunServers, &net.UDPAddr{IP: net.ParseIP(localIP)})
if err != nil {
logger.Infow("failed to get external ip", "local", localIP, "err", err)
return
}
addrCh <- ipmapping{externalIP: addr, localIP: localIP}
}(ip)
}
var firstResloved bool
natMapping := make(map[string]string)
timeout := time.NewTimer(5 * time.Second)
defer timeout.Stop()
done:
for {
select {
case mapping := <-addrCh:
if !firstResloved {
firstResloved = true
timeout.Reset(1 * time.Second)
}
if local, ok := natMapping[mapping.externalIP]; ok {
logger.Infow("external ip already solved, ignore duplicate",
"external", mapping.externalIP,
"local", local,
"ignore", mapping.localIP)
} else {
natMapping[mapping.externalIP] = mapping.localIP
}
case <-timeout.C:
break done
}
}
// mapping unresolved local ip to itself
for _, local := range localIPs {
var found bool
for _, localIPMapping := range natMapping {
if local == localIPMapping {
found = true
break
}
}
if !found {
natMapping[local] = local
}
}
nat1to1IPs := make([]string, 0, len(natMapping))
for external, local := range natMapping {
nat1to1IPs = append(nat1to1IPs, fmt.Sprintf("%s/%s", external, local))
}
return nat1to1IPs, nil
}
func InterfaceFilterFromConf(ifs config.InterfacesConfig) func(string) bool {
includes := ifs.Includes
excludes := ifs.Excludes
return func(s string) bool {
// filter by include interfaces
if len(includes) > 0 {
for _, iface := range includes {
if iface == s {
return true
}
}
return false
}
// filter by exclude interfaces
if len(excludes) > 0 {
for _, iface := range excludes {
if iface == s {
return false
}
}
}
return true
}
}
func IPFilterFromConf(ips config.IPsConfig) (func(ip net.IP) bool, error) {
var ipnets [2][]*net.IPNet
var err error
for i, ips := range [][]string{ips.Includes, ips.Excludes} {
ipnets[i], err = func(fromIPs []string) ([]*net.IPNet, error) {
var toNets []*net.IPNet
for _, ip := range fromIPs {
_, ipnet, err := net.ParseCIDR(ip)
if err != nil {
return nil, err
}
toNets = append(toNets, ipnet)
}
return toNets, nil
}(ips)
if err != nil {
return nil, err
}
}
includes, excludes := ipnets[0], ipnets[1]
return func(ip net.IP) bool {
if len(includes) > 0 {
for _, ipn := range includes {
if ipn.Contains(ip) {
return true
}
}
return false
}
if len(excludes) > 0 {
for _, ipn := range excludes {
if ipn.Contains(ip) {
return false
}
}
}
return true
}, nil
}