mediamtx/internal/core/webrtc_manager.go
2023-10-31 14:19:04 +01:00

571 lines
13 KiB
Go

package core
import (
"context"
"crypto/hmac"
"crypto/rand"
"crypto/sha1"
"encoding/base64"
"fmt"
"net"
"net/http"
"sort"
"strconv"
"sync"
"time"
"github.com/google/uuid"
"github.com/pion/ice/v2"
pwebrtc "github.com/pion/webrtc/v3"
"github.com/bluenviron/mediamtx/internal/conf"
"github.com/bluenviron/mediamtx/internal/defs"
"github.com/bluenviron/mediamtx/internal/externalcmd"
"github.com/bluenviron/mediamtx/internal/logger"
"github.com/bluenviron/mediamtx/internal/protocols/webrtc"
"github.com/bluenviron/mediamtx/internal/restrictnetwork"
)
const (
webrtcPauseAfterAuthError = 2 * time.Second
webrtcTurnSecretExpiration = 24 * 3600 * time.Second
webrtcPayloadMaxSize = 1188 // 1200 - 12 (RTP header)
)
func randInt63() (int64, error) {
var b [8]byte
_, err := rand.Read(b[:])
if err != nil {
return 0, err
}
return int64(uint64(b[0]&0b01111111)<<56 | uint64(b[1])<<48 | uint64(b[2])<<40 | uint64(b[3])<<32 |
uint64(b[4])<<24 | uint64(b[5])<<16 | uint64(b[6])<<8 | uint64(b[7])), nil
}
// https://cs.opensource.google/go/go/+/refs/tags/go1.20.4:src/math/rand/rand.go;l=119
func randInt63n(n int64) (int64, error) {
if n&(n-1) == 0 { // n is power of two, can mask
r, err := randInt63()
if err != nil {
return 0, err
}
return r & (n - 1), nil
}
max := int64((1 << 63) - 1 - (1<<63)%uint64(n))
v, err := randInt63()
if err != nil {
return 0, err
}
for v > max {
v, err = randInt63()
if err != nil {
return 0, err
}
}
return v % n, nil
}
func randomTurnUser() (string, error) {
const charset = "abcdefghijklmnopqrstuvwxyz1234567890"
b := make([]byte, 20)
for i := range b {
j, err := randInt63n(int64(len(charset)))
if err != nil {
return "", err
}
b[i] = charset[int(j)]
}
return string(b), nil
}
type webRTCManagerAPISessionsListRes struct {
data *defs.APIWebRTCSessionList
err error
}
type webRTCManagerAPISessionsListReq struct {
res chan webRTCManagerAPISessionsListRes
}
type webRTCManagerAPISessionsGetRes struct {
data *defs.APIWebRTCSession
err error
}
type webRTCManagerAPISessionsGetReq struct {
uuid uuid.UUID
res chan webRTCManagerAPISessionsGetRes
}
type webRTCManagerAPISessionsKickRes struct {
err error
}
type webRTCManagerAPISessionsKickReq struct {
uuid uuid.UUID
res chan webRTCManagerAPISessionsKickRes
}
type webRTCNewSessionRes struct {
sx *webRTCSession
answer []byte
errStatusCode int
err error
}
type webRTCNewSessionReq struct {
pathName string
remoteAddr string
query string
user string
pass string
offer []byte
publish bool
res chan webRTCNewSessionRes
}
type webRTCAddSessionCandidatesRes struct {
sx *webRTCSession
err error
}
type webRTCAddSessionCandidatesReq struct {
secret uuid.UUID
candidates []*pwebrtc.ICECandidateInit
res chan webRTCAddSessionCandidatesRes
}
type webRTCDeleteSessionRes struct {
err error
}
type webRTCDeleteSessionReq struct {
secret uuid.UUID
res chan webRTCDeleteSessionRes
}
type webRTCManagerParent interface {
logger.Writer
}
type webRTCManager struct {
allowOrigin string
trustedProxies conf.IPsOrCIDRs
iceServers []conf.WebRTCICEServer
writeQueueSize int
externalCmdPool *externalcmd.Pool
pathManager *pathManager
metrics *metrics
parent webRTCManagerParent
ctx context.Context
ctxCancel func()
httpServer *webRTCHTTPServer
udpMuxLn net.PacketConn
tcpMuxLn net.Listener
api *pwebrtc.API
sessions map[*webRTCSession]struct{}
sessionsBySecret map[uuid.UUID]*webRTCSession
// in
chNewSession chan webRTCNewSessionReq
chCloseSession chan *webRTCSession
chAddSessionCandidates chan webRTCAddSessionCandidatesReq
chDeleteSession chan webRTCDeleteSessionReq
chAPISessionsList chan webRTCManagerAPISessionsListReq
chAPISessionsGet chan webRTCManagerAPISessionsGetReq
chAPIConnsKick chan webRTCManagerAPISessionsKickReq
// out
done chan struct{}
}
func newWebRTCManager(
address string,
encryption bool,
serverKey string,
serverCert string,
allowOrigin string,
trustedProxies conf.IPsOrCIDRs,
iceServers []conf.WebRTCICEServer,
readTimeout conf.StringDuration,
writeQueueSize int,
iceInterfaces []string,
iceHostNAT1To1IPs []string,
iceUDPMuxAddress string,
iceTCPMuxAddress string,
externalCmdPool *externalcmd.Pool,
pathManager *pathManager,
metrics *metrics,
parent webRTCManagerParent,
) (*webRTCManager, error) {
ctx, ctxCancel := context.WithCancel(context.Background())
m := &webRTCManager{
allowOrigin: allowOrigin,
trustedProxies: trustedProxies,
iceServers: iceServers,
writeQueueSize: writeQueueSize,
externalCmdPool: externalCmdPool,
pathManager: pathManager,
metrics: metrics,
parent: parent,
ctx: ctx,
ctxCancel: ctxCancel,
sessions: make(map[*webRTCSession]struct{}),
sessionsBySecret: make(map[uuid.UUID]*webRTCSession),
chNewSession: make(chan webRTCNewSessionReq),
chCloseSession: make(chan *webRTCSession),
chAddSessionCandidates: make(chan webRTCAddSessionCandidatesReq),
chDeleteSession: make(chan webRTCDeleteSessionReq),
chAPISessionsList: make(chan webRTCManagerAPISessionsListReq),
chAPISessionsGet: make(chan webRTCManagerAPISessionsGetReq),
chAPIConnsKick: make(chan webRTCManagerAPISessionsKickReq),
done: make(chan struct{}),
}
var err error
m.httpServer, err = newWebRTCHTTPServer(
address,
encryption,
serverKey,
serverCert,
allowOrigin,
trustedProxies,
readTimeout,
pathManager,
m,
)
if err != nil {
ctxCancel()
return nil, err
}
var iceUDPMux ice.UDPMux
if iceUDPMuxAddress != "" {
m.udpMuxLn, err = net.ListenPacket(restrictnetwork.Restrict("udp", iceUDPMuxAddress))
if err != nil {
m.httpServer.close()
ctxCancel()
return nil, err
}
iceUDPMux = pwebrtc.NewICEUDPMux(nil, m.udpMuxLn)
}
var iceTCPMux ice.TCPMux
if iceTCPMuxAddress != "" {
m.tcpMuxLn, err = net.Listen(restrictnetwork.Restrict("tcp", iceTCPMuxAddress))
if err != nil {
m.udpMuxLn.Close()
m.httpServer.close()
ctxCancel()
return nil, err
}
iceTCPMux = pwebrtc.NewICETCPMux(nil, m.tcpMuxLn, 8)
}
m.api, err = webrtc.NewAPI(webrtc.APIConf{
ICEInterfaces: iceInterfaces,
ICEHostNAT1To1IPs: iceHostNAT1To1IPs,
ICEUDPMux: iceUDPMux,
ICETCPMux: iceTCPMux,
})
if err != nil {
m.udpMuxLn.Close()
m.tcpMuxLn.Close()
m.httpServer.close()
ctxCancel()
return nil, err
}
str := "listener opened on " + address + " (HTTP)"
if m.udpMuxLn != nil {
str += ", " + iceUDPMuxAddress + " (ICE/UDP)"
}
if m.tcpMuxLn != nil {
str += ", " + iceTCPMuxAddress + " (ICE/TCP)"
}
m.Log(logger.Info, str)
if m.metrics != nil {
m.metrics.webRTCManagerSet(m)
}
go m.run()
return m, nil
}
// Log is the main logging function.
func (m *webRTCManager) Log(level logger.Level, format string, args ...interface{}) {
m.parent.Log(level, "[WebRTC] "+format, args...)
}
func (m *webRTCManager) close() {
m.Log(logger.Info, "listener is closing")
m.ctxCancel()
<-m.done
}
func (m *webRTCManager) run() {
defer close(m.done)
var wg sync.WaitGroup
outer:
for {
select {
case req := <-m.chNewSession:
sx := newWebRTCSession(
m.ctx,
m.writeQueueSize,
m.api,
req,
&wg,
m.externalCmdPool,
m.pathManager,
m,
)
m.sessions[sx] = struct{}{}
m.sessionsBySecret[sx.secret] = sx
req.res <- webRTCNewSessionRes{sx: sx}
case sx := <-m.chCloseSession:
delete(m.sessions, sx)
delete(m.sessionsBySecret, sx.secret)
case req := <-m.chAddSessionCandidates:
sx, ok := m.sessionsBySecret[req.secret]
if !ok {
req.res <- webRTCAddSessionCandidatesRes{err: fmt.Errorf("session not found")}
continue
}
req.res <- webRTCAddSessionCandidatesRes{sx: sx}
case req := <-m.chDeleteSession:
sx, ok := m.sessionsBySecret[req.secret]
if !ok {
req.res <- webRTCDeleteSessionRes{err: fmt.Errorf("session not found")}
continue
}
delete(m.sessions, sx)
delete(m.sessionsBySecret, sx.secret)
sx.close()
req.res <- webRTCDeleteSessionRes{}
case req := <-m.chAPISessionsList:
data := &defs.APIWebRTCSessionList{
Items: []*defs.APIWebRTCSession{},
}
for sx := range m.sessions {
data.Items = append(data.Items, sx.apiItem())
}
sort.Slice(data.Items, func(i, j int) bool {
return data.Items[i].Created.Before(data.Items[j].Created)
})
req.res <- webRTCManagerAPISessionsListRes{data: data}
case req := <-m.chAPISessionsGet:
sx := m.findSessionByUUID(req.uuid)
if sx == nil {
req.res <- webRTCManagerAPISessionsGetRes{err: fmt.Errorf("session not found")}
continue
}
req.res <- webRTCManagerAPISessionsGetRes{data: sx.apiItem()}
case req := <-m.chAPIConnsKick:
sx := m.findSessionByUUID(req.uuid)
if sx == nil {
req.res <- webRTCManagerAPISessionsKickRes{err: fmt.Errorf("session not found")}
continue
}
delete(m.sessions, sx)
delete(m.sessionsBySecret, sx.secret)
sx.close()
req.res <- webRTCManagerAPISessionsKickRes{}
case <-m.ctx.Done():
break outer
}
}
m.ctxCancel()
wg.Wait()
m.httpServer.close()
if m.udpMuxLn != nil {
m.udpMuxLn.Close()
}
if m.tcpMuxLn != nil {
m.tcpMuxLn.Close()
}
}
func (m *webRTCManager) findSessionByUUID(uuid uuid.UUID) *webRTCSession {
for sx := range m.sessions {
if sx.uuid == uuid {
return sx
}
}
return nil
}
func (m *webRTCManager) generateICEServers() ([]pwebrtc.ICEServer, error) {
ret := make([]pwebrtc.ICEServer, len(m.iceServers))
for i, server := range m.iceServers {
if server.Username == "AUTH_SECRET" {
expireDate := time.Now().Add(webrtcTurnSecretExpiration).Unix()
user, err := randomTurnUser()
if err != nil {
return nil, err
}
server.Username = strconv.FormatInt(expireDate, 10) + ":" + user
h := hmac.New(sha1.New, []byte(server.Password))
h.Write([]byte(server.Username))
server.Password = base64.StdEncoding.EncodeToString(h.Sum(nil))
}
ret[i] = pwebrtc.ICEServer{
URLs: []string{server.URL},
Username: server.Username,
Credential: server.Password,
}
}
return ret, nil
}
// newSession is called by webRTCHTTPServer.
func (m *webRTCManager) newSession(req webRTCNewSessionReq) webRTCNewSessionRes {
req.res = make(chan webRTCNewSessionRes)
select {
case m.chNewSession <- req:
res := <-req.res
return res.sx.new(req)
case <-m.ctx.Done():
return webRTCNewSessionRes{
errStatusCode: http.StatusInternalServerError,
err: fmt.Errorf("terminated"),
}
}
}
// closeSession is called by webRTCSession.
func (m *webRTCManager) closeSession(sx *webRTCSession) {
select {
case m.chCloseSession <- sx:
case <-m.ctx.Done():
}
}
// addSessionCandidates is called by webRTCHTTPServer.
func (m *webRTCManager) addSessionCandidates(
req webRTCAddSessionCandidatesReq,
) webRTCAddSessionCandidatesRes {
req.res = make(chan webRTCAddSessionCandidatesRes)
select {
case m.chAddSessionCandidates <- req:
res1 := <-req.res
if res1.err != nil {
return res1
}
return res1.sx.addCandidates(req)
case <-m.ctx.Done():
return webRTCAddSessionCandidatesRes{err: fmt.Errorf("terminated")}
}
}
// deleteSession is called by webRTCHTTPServer.
func (m *webRTCManager) deleteSession(req webRTCDeleteSessionReq) error {
req.res = make(chan webRTCDeleteSessionRes)
select {
case m.chDeleteSession <- req:
res := <-req.res
return res.err
case <-m.ctx.Done():
return fmt.Errorf("terminated")
}
}
// apiSessionsList is called by api.
func (m *webRTCManager) apiSessionsList() (*defs.APIWebRTCSessionList, error) {
req := webRTCManagerAPISessionsListReq{
res: make(chan webRTCManagerAPISessionsListRes),
}
select {
case m.chAPISessionsList <- req:
res := <-req.res
return res.data, res.err
case <-m.ctx.Done():
return nil, fmt.Errorf("terminated")
}
}
// apiSessionsGet is called by api.
func (m *webRTCManager) apiSessionsGet(uuid uuid.UUID) (*defs.APIWebRTCSession, error) {
req := webRTCManagerAPISessionsGetReq{
uuid: uuid,
res: make(chan webRTCManagerAPISessionsGetRes),
}
select {
case m.chAPISessionsGet <- req:
res := <-req.res
return res.data, res.err
case <-m.ctx.Done():
return nil, fmt.Errorf("terminated")
}
}
// apiSessionsKick is called by api.
func (m *webRTCManager) apiSessionsKick(uuid uuid.UUID) error {
req := webRTCManagerAPISessionsKickReq{
uuid: uuid,
res: make(chan webRTCManagerAPISessionsKickRes),
}
select {
case m.chAPIConnsKick <- req:
res := <-req.res
return res.err
case <-m.ctx.Done():
return fmt.Errorf("terminated")
}
}