av/rtmp/rtmp.go

726 lines
18 KiB
Go

/*
NAME
rtmp.go
DESCRIPTION
RTMP command functionality.
AUTHORS
Saxon Nelson-Milton <saxon@ausocean.org>
Dan Kortschak <dan@ausocean.org>
Alan Noble <alan@ausocean.org>
LICENSE
rtmp.go is Copyright (C) 2017-2019 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
It is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with revid in gpl.txt. If not, see http://www.gnu.org/licenses.
Derived from librtmp under the GNU Lesser General Public License 2.1
Copyright (C) 2005-2008 Team XBMC http://www.xbmc.org
Copyright (C) 2008-2009 Andrej Stepanchuk
Copyright (C) 2009-2010 Howard Chu
*/
package rtmp
import (
"bytes"
"encoding/binary"
"errors"
"math/rand"
"net"
"strconv"
"time"
"bitbucket.org/ausocean/av/rtmp/amf"
)
const (
pkg = "rtmp:"
signatureSize = 1536
fullHeaderSize = 12
)
// Link flags.
const (
linkAuth = 0x0001 // using auth param
linkLive = 0x0002 // stream is live
linkSWF = 0x0004 // do SWF verification - not implemented
linkPlaylist = 0x0008 // send playlist before play - not implemented
linkBufx = 0x0010 // toggle stream on BufferEmpty msg - not implemented
)
// Protocol features.
const (
featureHTTP = 0x01 // not implemented
featureEncode = 0x02 // not implemented
featureSSL = 0x04 // not implemented
featureMFP = 0x08 // not implemented
featureWrite = 0x10 // publish, not play
featureHTTP2 = 0x20 // server-side RTMPT - not implemented
)
// RTMP protocols.
const (
protoRTMP = 0
protoRTMPE = featureEncode
protoRTMPT = featureHTTP
protoRTMPS = featureSSL
protoRTMPTE = (featureHTTP | featureEncode)
protoRTMPTS = (featureHTTP | featureSSL)
protoRTMFP = featureMFP
)
// RTMP tokens (lexemes).
// NB: Underscores are deliberately preserved in const names where they exist in the corresponding tokens.
const (
av_checkbw = "_checkbw"
av_onbwcheck = "_onbwcheck"
av_onbwdone = "_onbwdone"
av_result = "_result"
avApp = "app"
avAudioCodecs = "audioCodecs"
avCapabilities = "capabilities"
avClose = "close"
avCode = "code"
avConnect = "connect"
avCreatestream = "createStream"
avDeletestream = "deleteStream"
avFCPublish = "FCPublish"
avFCUnpublish = "FCUnpublish"
avFlashver = "flashVer"
avFpad = "fpad"
avLevel = "level"
avLive = "live"
avNetConnectionConnectInvalidApp = "NetConnection.Connect.InvalidApp"
avNetStreamFailed = "NetStream.Failed"
avNetStreamPauseNotify = "NetStream.Pause.Notify"
avNetStreamPlayComplete = "NetStream.Play.Complete"
avNetStreamPlayFailed = "NetStream.Play.Failed"
avNetStreamPlayPublishNotify = "NetStream.Play.PublishNotify"
avNetStreamPlayStart = "NetStream.Play.Start"
avNetStreamPlayStop = "NetStream.Play.Stop"
avNetStreamPlayStreamNotFound = "NetStream.Play.StreamNotFound"
avNetStreamPlayUnpublishNotify = "NetStream.Play.UnpublishNotify"
avNetStreamPublish_Start = "NetStream.Publish.Start"
avNetStreamSeekNotify = "NetStream.Seek.Notify"
avNonprivate = "nonprivate"
avObjectEncoding = "objectEncoding"
avOnBWDone = "onBWDone"
avOnFCSubscribe = "onFCSubscribe"
avOnFCUnsubscribe = "onFCUnsubscribe"
avOnStatus = "onStatus"
avPageUrl = "pageUrl"
avPing = "ping"
avPlay = "play"
avPlaylist_ready = "playlist_ready"
avPublish = "publish"
avReleasestream = "releaseStream"
avSecureToken = "secureToken"
avSet_playlist = "set_playlist"
avSwfUrl = "swfUrl"
avTcUrl = "tcUrl"
avType = "type"
avVideoCodecs = "videoCodecs"
avVideoFunction = "videoFunction"
)
// RTMP protocol strings.
var rtmpProtocolStrings = [...]string{
"rtmp",
"rtmpt",
"rtmpe",
"rtmpte",
"rtmps",
"rtmpts",
"",
"",
"rtmfp",
}
// RTMP errors.
var (
errUnknownScheme = errors.New("rtmp: unknown scheme")
errInvalidURL = errors.New("rtmp: invalid URL")
errConnected = errors.New("rtmp: already connected")
errNotConnected = errors.New("rtmp: not connected")
errNotWritable = errors.New("rtmp: connection not writable")
errInvalidHeader = errors.New("rtmp: invalid header")
errInvalidBody = errors.New("rtmp: invalid body")
errInvalidFlvTag = errors.New("rtmp: invalid FLV tag")
errUnimplemented = errors.New("rtmp: unimplemented feature")
)
// connect establishes an RTMP connection.
func connect(c *Conn) error {
addr, err := net.ResolveTCPAddr("tcp4", c.link.host+":"+strconv.Itoa(int(c.link.port)))
if err != nil {
return err
}
c.link.conn, err = net.DialTCP("tcp4", nil, addr)
if err != nil {
c.log(WarnLevel, pkg+"dial failed", "error", err.Error())
return err
}
c.log(DebugLevel, pkg+"connected")
err = handshake(c)
if err != nil {
c.log(WarnLevel, pkg+"handshake failed", "error", err.Error())
return err
}
c.log(DebugLevel, pkg+"handshaked")
err = sendConnectPacket(c)
if err != nil {
c.log(WarnLevel, pkg+"sendConnect failed", "error", err.Error())
return err
}
c.log(DebugLevel, pkg+"negotiating")
for !c.isPlaying {
pkt := packet{}
err = pkt.readFrom(c)
if err != nil {
break
}
switch pkt.packetType {
case packetTypeAudio, packetTypeVideo, packetTypeInfo:
c.log(WarnLevel, pkg+"got packet before play; ignoring", "type", pkt.packetType)
default:
err = handlePacket(c, &pkt)
if err != nil {
break
}
}
}
if !c.isPlaying {
return err
}
return nil
}
// handlePacket handles a packet that the client has received.
// NB: Unsupported packet types are logged fatally.
func handlePacket(c *Conn, pkt *packet) error {
if pkt.bodySize < 4 {
return errInvalidBody
}
switch pkt.packetType {
case packetTypeChunkSize:
c.inChunkSize = amf.DecodeInt32(pkt.body[:4])
c.log(DebugLevel, pkg+"set inChunkSize", "size", int(c.inChunkSize))
case packetTypeBytesReadReport:
c.log(DebugLevel, pkg+"received packetTypeBytesReadReport")
case packetTypeServerBW:
c.serverBW = amf.DecodeInt32(pkt.body[:4])
c.log(DebugLevel, pkg+"set serverBW", "size", int(c.serverBW))
case packetTypeClientBW:
c.clientBW = amf.DecodeInt32(pkt.body[:4])
c.log(DebugLevel, pkg+"set clientBW", "size", int(c.clientBW))
if pkt.bodySize > 4 {
c.clientBW2 = pkt.body[4]
c.log(DebugLevel, pkg+"set clientBW2", "size", int(c.clientBW2))
} else {
c.clientBW2 = 0xff
}
case packetTypeInvoke:
err := handleInvoke(c, pkt.body[:pkt.bodySize])
if err != nil {
c.log(WarnLevel, pkg+"unexpected error from handleInvoke", "error", err.Error())
return err
}
case packetTypeControl, packetTypeAudio, packetTypeVideo, packetTypeFlashVideo, packetTypeFlexMessage, packetTypeInfo:
c.log(FatalLevel, pkg+"unsupported packet type "+strconv.Itoa(int(pkt.packetType)))
default:
c.log(WarnLevel, pkg+"unknown packet type", "type", pkt.packetType)
}
return nil
}
func sendConnectPacket(c *Conn) error {
var pbuf [4096]byte
pkt := packet{
channel: chanControl,
headerType: headerSizeLarge,
packetType: packetTypeInvoke,
header: pbuf[:],
body: pbuf[fullHeaderSize:],
}
enc := pkt.body
enc, err := amf.EncodeString(enc, avConnect)
if err != nil {
return err
}
c.numInvokes += 1
enc, err = amf.EncodeNumber(enc, float64(c.numInvokes))
if err != nil {
return err
}
enc[0] = amf.TypeObject
enc = enc[1:]
enc, err = amf.EncodeNamedString(enc, avApp, c.link.app)
if err != nil {
return err
}
enc, err = amf.EncodeNamedString(enc, avType, avNonprivate)
if err != nil {
return err
}
enc, err = amf.EncodeNamedString(enc, avTcUrl, c.link.url)
if err != nil {
return err
}
enc, err = amf.EncodeInt24(enc, amf.TypeObjectEnd)
if err != nil {
return err
}
// add auth string, if any
if c.link.auth != "" {
enc, err = amf.EncodeBoolean(enc, c.link.flags&linkAuth != 0)
if err != nil {
return err
}
enc, err = amf.EncodeString(enc, c.link.auth)
if err != nil {
return err
}
}
pkt.bodySize = uint32((len(pbuf) - fullHeaderSize) - len(enc))
return pkt.writeTo(c, true) // response expected
}
func sendCreateStream(c *Conn) error {
var pbuf [256]byte
pkt := packet{
channel: chanControl,
headerType: headerSizeMedium,
packetType: packetTypeInvoke,
header: pbuf[:],
body: pbuf[fullHeaderSize:],
}
enc := pkt.body
enc, err := amf.EncodeString(enc, avCreatestream)
if err != nil {
return err
}
c.numInvokes++
enc, err = amf.EncodeNumber(enc, float64(c.numInvokes))
if err != nil {
return err
}
enc[0] = amf.TypeNull
enc = enc[1:]
pkt.bodySize = uint32((len(pbuf) - fullHeaderSize) - len(enc))
return pkt.writeTo(c, true) // response expected
}
func sendReleaseStream(c *Conn) error {
var pbuf [1024]byte
pkt := packet{
channel: chanControl,
headerType: headerSizeMedium,
packetType: packetTypeInvoke,
header: pbuf[:],
body: pbuf[fullHeaderSize:],
}
enc := pkt.body
enc, err := amf.EncodeString(enc, avReleasestream)
if err != nil {
return err
}
c.numInvokes++
enc, err = amf.EncodeNumber(enc, float64(c.numInvokes))
if err != nil {
return err
}
enc[0] = amf.TypeNull
enc = enc[1:]
enc, err = amf.EncodeString(enc, c.link.playpath)
if err != nil {
return err
}
pkt.bodySize = uint32((len(pbuf) - fullHeaderSize) - len(enc))
return pkt.writeTo(c, false)
}
func sendFCPublish(c *Conn) error {
var pbuf [1024]byte
pkt := packet{
channel: chanControl,
headerType: headerSizeMedium,
packetType: packetTypeInvoke,
header: pbuf[:],
body: pbuf[fullHeaderSize:],
}
enc := pkt.body
enc, err := amf.EncodeString(enc, avFCPublish)
if err != nil {
return err
}
c.numInvokes++
enc, err = amf.EncodeNumber(enc, float64(c.numInvokes))
if err != nil {
return err
}
enc[0] = amf.TypeNull
enc = enc[1:]
enc, err = amf.EncodeString(enc, c.link.playpath)
if err != nil {
return err
}
pkt.bodySize = uint32((len(pbuf) - fullHeaderSize) - len(enc))
return pkt.writeTo(c, false)
}
func sendFCUnpublish(c *Conn) error {
var pbuf [1024]byte
pkt := packet{
channel: chanControl,
headerType: headerSizeMedium,
packetType: packetTypeInvoke,
header: pbuf[:],
body: pbuf[fullHeaderSize:],
}
enc := pkt.body
enc, err := amf.EncodeString(enc, avFCUnpublish)
if err != nil {
return err
}
c.numInvokes++
enc, err = amf.EncodeNumber(enc, float64(c.numInvokes))
if err != nil {
return err
}
enc[0] = amf.TypeNull
enc = enc[1:]
enc, err = amf.EncodeString(enc, c.link.playpath)
if err != nil {
return err
}
pkt.bodySize = uint32((len(pbuf) - fullHeaderSize) - len(enc))
return pkt.writeTo(c, false)
}
func sendPublish(c *Conn) error {
var pbuf [1024]byte
pkt := packet{
channel: chanSource,
headerType: headerSizeLarge,
packetType: packetTypeInvoke,
header: pbuf[:],
body: pbuf[fullHeaderSize:],
}
enc := pkt.body
enc, err := amf.EncodeString(enc, avPublish)
if err != nil {
return err
}
c.numInvokes++
enc, err = amf.EncodeNumber(enc, float64(c.numInvokes))
if err != nil {
return err
}
enc[0] = amf.TypeNull
enc = enc[1:]
enc, err = amf.EncodeString(enc, c.link.playpath)
if err != nil {
return err
}
enc, err = amf.EncodeString(enc, avLive)
if err != nil {
return err
}
pkt.bodySize = uint32((len(pbuf) - fullHeaderSize) - len(enc))
return pkt.writeTo(c, true) // response expected
}
func sendDeleteStream(c *Conn, dStreamId float64) error {
var pbuf [256]byte
pkt := packet{
channel: chanControl,
headerType: headerSizeMedium,
packetType: packetTypeInvoke,
header: pbuf[:],
body: pbuf[fullHeaderSize:],
}
enc := pkt.body
enc, err := amf.EncodeString(enc, avDeletestream)
if err != nil {
return err
}
c.numInvokes++
enc, err = amf.EncodeNumber(enc, float64(c.numInvokes))
if err != nil {
return err
}
enc[0] = amf.TypeNull
enc = enc[1:]
enc, err = amf.EncodeNumber(enc, dStreamId)
if err != nil {
return err
}
pkt.bodySize = uint32((len(pbuf) - fullHeaderSize) - len(enc))
return pkt.writeTo(c, false)
}
// sendBytesReceived tells the server how many bytes the client has received.
func sendBytesReceived(c *Conn) error {
var pbuf [256]byte
pkt := packet{
channel: chanBytesRead,
headerType: headerSizeMedium,
packetType: packetTypeBytesReadReport,
header: pbuf[:],
body: pbuf[fullHeaderSize:],
}
enc := pkt.body
c.nBytesInSent = c.nBytesIn
enc, err := amf.EncodeInt32(enc, c.nBytesIn)
if err != nil {
return err
}
pkt.bodySize = 4
return pkt.writeTo(c, false)
}
func sendCheckBW(c *Conn) error {
var pbuf [256]byte
pkt := packet{
channel: chanControl,
headerType: headerSizeLarge,
packetType: packetTypeInvoke,
header: pbuf[:],
body: pbuf[fullHeaderSize:],
}
enc := pkt.body
enc, err := amf.EncodeString(enc, av_checkbw)
if err != nil {
return err
}
c.numInvokes++
enc, err = amf.EncodeNumber(enc, float64(c.numInvokes))
if err != nil {
return err
}
enc[0] = amf.TypeNull
enc = enc[1:]
pkt.bodySize = uint32((len(pbuf) - fullHeaderSize) - len(enc))
return pkt.writeTo(c, false)
}
func eraseMethod(m []method, i int) []method {
copy(m[i:], m[i+1:])
m[len(m)-1] = method{}
return m[:len(m)-1]
}
// int handleInvoke handles a packet invoke request
// Side effects: c.isPlaying set to true upon avNetStreamPublish_Start
func handleInvoke(c *Conn, body []byte) error {
if body[0] != 0x02 {
return errInvalidBody
}
var obj amf.Object
_, err := amf.Decode(&obj, body, false)
if err != nil {
return err
}
meth, err := obj.StringProperty("", 0)
if err != nil {
return err
}
txn, err := obj.NumberProperty("", 1)
if err != nil {
return err
}
c.log(DebugLevel, pkg+"invoking method "+meth)
switch meth {
case av_result:
if (c.link.protocol & featureWrite) == 0 {
return errNotWritable
}
var methodInvoked string
for i, m := range c.methodCalls {
if float64(m.num) == txn {
methodInvoked = m.name
c.methodCalls = eraseMethod(c.methodCalls, i)
break
}
}
if methodInvoked == "" {
c.log(WarnLevel, pkg+"received result without matching request", "id", txn)
return nil
}
c.log(DebugLevel, pkg+"received result for "+methodInvoked)
switch methodInvoked {
case avConnect:
err := sendReleaseStream(c)
if err != nil {
return err
}
err = sendFCPublish(c)
if err != nil {
return err
}
err = sendCreateStream(c)
if err != nil {
return err
}
case avCreatestream:
n, err := obj.NumberProperty("", 3)
if err != nil {
return err
}
c.streamID = int32(n)
err = sendPublish(c)
if err != nil {
return err
}
default:
c.log(FatalLevel, pkg+"unexpected method invoked"+methodInvoked)
}
case avOnBWDone:
err := sendCheckBW(c)
if err != nil {
return err
}
case avOnStatus:
obj2, err := obj.ObjectProperty("", 3)
if err != nil {
return err
}
code, err := obj2.StringProperty(avCode, -1)
if err != nil {
return err
}
level, err := obj2.StringProperty(avLevel, -1)
if err != nil {
return err
}
c.log(DebugLevel, pkg+"onStatus", "code", code, "level", level)
if code != avNetStreamPublish_Start {
c.log(ErrorLevel, pkg+"unexpected response "+code)
return errUnimplemented
}
c.log(DebugLevel, pkg+"playing")
c.isPlaying = true
for i, m := range c.methodCalls {
if m.name == avPublish {
c.methodCalls = eraseMethod(c.methodCalls, i)
}
}
default:
c.log(FatalLevel, pkg+"unsuppoted method "+meth)
}
return nil
}
func handshake(c *Conn) error {
var clientbuf [signatureSize + 1]byte
clientsig := clientbuf[1:]
var serversig [signatureSize]byte
clientbuf[0] = chanControl
binary.BigEndian.PutUint32(clientsig, uint32(time.Now().UnixNano()/1000000))
copy(clientsig[4:8], []byte{0, 0, 0, 0})
for i := 8; i < signatureSize; i++ {
clientsig[i] = byte(rand.Intn(256))
}
_, err := c.write(clientbuf[:])
if err != nil {
return err
}
c.log(DebugLevel, pkg+"handshake sent")
var typ [1]byte
_, err = c.read(typ[:])
if err != nil {
return err
}
c.log(DebugLevel, pkg+"handshake received")
if typ[0] != clientbuf[0] {
c.log(WarnLevel, pkg+"handshake type mismatch", "sent", clientbuf[0], "received", typ)
}
_, err = c.read(serversig[:])
if err != nil {
return err
}
// decode server response
suptime := binary.BigEndian.Uint32(serversig[:4])
c.log(DebugLevel, pkg+"server uptime", "uptime", suptime)
// 2nd part of handshake
_, err = c.write(serversig[:])
if err != nil {
return err
}
_, err = c.read(serversig[:])
if err != nil {
return err
}
if !bytes.Equal(serversig[:signatureSize], clientbuf[1:signatureSize+1]) {
c.log(WarnLevel, pkg+"signature mismatch", "serversig", serversig[:signatureSize], "clientsig", clientbuf[1:signatureSize+1])
}
return nil
}