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mirror of https://github.com/wader/fq.git synced 2024-11-25 23:13:19 +03:00
fq/format/rtmp/rtmp.go
2023-05-01 13:19:04 +02:00

488 lines
15 KiB
Go

package rtmp
// https://rtmp.veriskope.com/docs/spec/
// https://rtmp.veriskope.com/pdf/video_file_format_spec_v10.pdf
// TODO: split to rtmp/rtmp_message?
// TODO: support to skip handshake?
// TODO: keep track of message stream format, decode aac etc
import (
"bytes"
"embed"
"github.com/wader/fq/format"
"github.com/wader/fq/pkg/bitio"
"github.com/wader/fq/pkg/decode"
"github.com/wader/fq/pkg/interp"
"github.com/wader/fq/pkg/scalar"
)
var rtmpAmf0Group decode.Group
var rtmpMpegASCGroup decode.Group
//go:embed rtmp.md
var rtmpFS embed.FS
func init() {
interp.RegisterFormat(
format.RTMP,
&decode.Format{
Description: "Real-Time Messaging Protocol",
Groups: []*decode.Group{
format.TCP_Stream,
},
DecodeFn: rtmpDecode,
Dependencies: []decode.Dependency{
{Groups: []*decode.Group{format.AMF0}, Out: &rtmpAmf0Group},
{Groups: []*decode.Group{format.MPEG_ASC}, Out: &rtmpMpegASCGroup},
},
})
interp.RegisterFS(rtmpFS)
}
// from RTMP spec
const defaultChunkSize = 128
// names from RTMP spec
const (
messageTypeSetChunkSize = 1
messageTypeAbortMessage = 2
messageTypeAcknowledgment = 3
messageTypeUserControlMessage = 4
messageTypeWindowAcknowledgementSize = 5
messageTypeSetPeerBandwidth = 6
messageTypeVirtualControl = 7 // TODO: not in spec but in wikipedia article
messageTypeAudioMessage = 8
messageTypeVideoMessage = 9
messageTypeDataMessageExtended = 15
messageTypeSharedObjectMessageExtended = 16
messageTypeCommandMessageExtended = 17
messageTypeDataMessage = 18
messageTypeSharedObjectMessage = 19
messageTypeCommandMessage = 20
messageTypeUDP = 21 // TODO: not in spec but in wikipedia article
messageTypeAggregateMessage = 22
messageTypePresent = 23 // TODO: not in spec but in wikipedia article
)
var rtmpMessageTypeIDNames = scalar.UintMapSymStr{
messageTypeSetChunkSize: "set_chunk_size",
messageTypeAbortMessage: "abort_message",
messageTypeAcknowledgment: "acknowledgment",
messageTypeUserControlMessage: "user_control_message",
messageTypeWindowAcknowledgementSize: "window_acknowledgement_size",
messageTypeSetPeerBandwidth: "set_peer_bandwidth",
messageTypeVirtualControl: "virtual_control",
messageTypeAudioMessage: "audio_message",
messageTypeVideoMessage: "video_message",
messageTypeDataMessageExtended: "data_message_extended",
messageTypeSharedObjectMessageExtended: "shared_object_message_extended",
messageTypeCommandMessageExtended: "command_message_extended",
messageTypeDataMessage: "data_message",
messageTypeSharedObjectMessage: "shared_object_message",
messageTypeCommandMessage: "command_message",
messageTypeUDP: "udp",
messageTypeAggregateMessage: "aggregate_message",
messageTypePresent: "present",
}
const (
userControlEvenTypeStreamBegin = 0
userControlEvenTypeStreamEOF = 1
userControlEvenTypeStreamDry = 2
userControlEvenTypeSetBufferLength = 3
userControlEvenTypeStreamIsRecorded = 4
userControlEvenTypePingRequest = 6
userControlEvenTypePingResponse = 7
)
var userControlEvenTypNames = scalar.UintMapSymStr{
userControlEvenTypeStreamBegin: "stream_begin",
userControlEvenTypeStreamEOF: "stream_eof",
userControlEvenTypeStreamDry: "stream_dry",
userControlEvenTypeSetBufferLength: "set_buffer_length",
userControlEvenTypeStreamIsRecorded: "stream_is_recorded",
userControlEvenTypePingRequest: "ping_request",
userControlEvenTypePingResponse: "ping_response",
}
var setPeerBandwidthLimitTypeName = scalar.UintMapSymStr{
0: "hard",
1: "soft",
2: "dynamic",
}
const timestampExtended = 0xff_ff_ff
var timestampUintDescription = scalar.UintMapDescription{
timestampExtended: "extended",
}
const (
audioMessageCodecAAC = 10
)
// based on https://github.com/wireshark/wireshark/blob/master/epan/dissectors/packet-rtmpt.c
// which in turn is based on rtmp and swf specifications and FLV v10.1 section E.4.3.1
var audioMessageCodecNames = scalar.UintMapSymStr{
0: "uncompressed",
1: "adpcm",
2: "mp3",
3: "uncompressed_le",
4: "nellymoser_16khz",
5: "nellymoser_8khz",
6: "nellymoser",
7: "g711a",
8: "g711u",
9: "nellymoser_16khz",
audioMessageCodecAAC: "aac",
11: "speex",
}
const (
audioMessageAACPacketTypeASC = 0
audioMessageAACPacketTypeRaw = 1
)
var audioMessageAACPacketTypeNames = scalar.UintMapSymStr{
audioMessageAACPacketTypeASC: "asc",
audioMessageAACPacketTypeRaw: "raw",
}
var audioMessageRateNames = scalar.UintMapSymUint{
0: 5500,
1: 11025,
2: 22050,
3: 44100,
}
var audioMessageSampleSize = scalar.UintMapSymUint{
0: 8,
1: 16,
}
var audioMessageChannels = scalar.UintMapSymUint{
0: 1,
1: 2,
}
var videoMessageTypeNames = scalar.UintMapSymStr{
1: "keyframe",
2: "inter_frame",
3: "disposable_inter_frame",
4: "generated_key_frame",
5: "video_info_or_command_frame",
}
const (
videoMessageCodecH264 = 7
)
var videoMessageCodecNames = scalar.UintMapSymStr{
2: "h263",
3: "screen_video",
4: "vp6",
5: "vp6_alpha",
6: "screen_video_v2",
videoMessageCodecH264: "h264",
}
var videoMessageH264PacketTypeNames = scalar.UintMapSymStr{
0: "dcr",
1: "au", // TODO: is access unit?
2: "empty",
}
// TODO: invalid warning that timestampDelta is unused
//nolint:unused
type messageHeader struct {
timestamp uint64
timestampDelta uint64
messageStreamID uint64
messageLength uint64
messageTypeID uint64
}
func rtmpDecodeMessageType(d *decode.D, typ int, chunkSize *int) {
switch typ {
case messageTypeSetChunkSize:
// TODO: zero bit, verify size? message size is 24 bit
*chunkSize = int(d.FieldU32("size"))
case messageTypeAbortMessage:
d.FieldU32("chunk_stream_id")
case messageTypeAcknowledgment:
d.FieldU32("sequence_number")
case messageTypeUserControlMessage:
typ := d.FieldU16("type", userControlEvenTypNames)
switch typ {
case userControlEvenTypeStreamBegin:
d.FieldU32("stream_id")
case userControlEvenTypeStreamEOF:
d.FieldU32("stream_id")
case userControlEvenTypeStreamDry:
d.FieldU32("stream_id")
case userControlEvenTypeSetBufferLength:
d.FieldU32("stream_id")
d.FieldU32("length")
case userControlEvenTypeStreamIsRecorded:
d.FieldU32("stream_id")
case userControlEvenTypePingRequest:
d.FieldU32("timestamp")
case userControlEvenTypePingResponse:
d.FieldU32("timestamp")
default:
d.FieldRawLen("data", d.BitsLeft())
}
case messageTypeWindowAcknowledgementSize:
d.FieldU32("window_size")
case messageTypeSetPeerBandwidth:
d.FieldU32("chunk_size")
d.FieldU8("limit_type", setPeerBandwidthLimitTypeName)
case messageTypeDataMessage:
d.FieldArray("messages", func(d *decode.D) {
for !d.End() {
d.FieldFormat("message", &rtmpAmf0Group, nil)
}
})
case messageTypeCommandMessage:
d.FieldFormat("command_name", &rtmpAmf0Group, nil)
d.FieldFormat("transaction_id", &rtmpAmf0Group, nil)
d.FieldFormat("command_object", &rtmpAmf0Group, nil)
d.FieldArray("arguments", func(d *decode.D) {
for !d.End() {
d.FieldFormat("argument", &rtmpAmf0Group, nil)
}
})
case messageTypeAggregateMessage:
d.FieldArray("messages", func(d *decode.D) {
for !d.End() {
d.FieldStruct("message", func(d *decode.D) {
var h messageHeader
h.messageTypeID = d.FieldU8("message_type_id", rtmpMessageTypeIDNames)
h.messageLength = d.FieldU24("message_length")
h.timestamp = d.FieldU32("timestamp", timestampUintDescription)
h.messageStreamID = d.FieldU24("message_stream_id")
// TODO: possible to set chunk size in aggregated message?
d.FramedFn(int64(h.messageLength*8), func(d *decode.D) {
rtmpDecodeMessageType(d, int(h.messageTypeID), chunkSize)
})
d.FieldU32("back_pointer")
})
}
})
case messageTypeAudioMessage:
if d.BitsLeft() == 0 {
return
}
codec := d.FieldU4("codec", audioMessageCodecNames)
d.FieldU2("sample_rate", audioMessageRateNames)
d.FieldU1("sample_size", audioMessageSampleSize)
d.FieldU1("channels", audioMessageChannels)
if codec == audioMessageCodecAAC {
switch d.FieldU8("type", audioMessageAACPacketTypeNames) {
case audioMessageAACPacketTypeASC:
d.FieldFormat("data", &rtmpMpegASCGroup, nil)
default:
d.FieldRawLen("data", d.BitsLeft())
}
} else {
d.FieldRawLen("data", d.BitsLeft())
}
case messageTypeVideoMessage:
if d.BitsLeft() == 0 {
return
}
d.FieldU4("type", videoMessageTypeNames)
codec := d.FieldU4("codec", videoMessageCodecNames)
// TODO: flv header + h263 format?
// TODO: ffmpeg rtmp proto seems to recrate a flv stream and demux it
if codec == videoMessageCodecH264 {
d.FieldU8("type", videoMessageH264PacketTypeNames)
}
d.FieldRawLen("data", d.BitsLeft())
default:
d.FieldRawLen("data", d.BitsLeft())
}
}
func rtmpDecode(d *decode.D) any {
var isClient bool
var tsi format.TCP_Stream_In
if d.ArgAs(&tsi) {
tsi.MustIsPort(d.Fatalf, format.TCPPortRTMP)
isClient = tsi.IsClient
}
// chunk size is global for one direction
chunkSize := defaultChunkSize
name := "s"
if isClient {
name = "c"
}
// TODO: 1536 byte blobs instead?
d.FieldStruct("handshake", func(d *decode.D) {
d.FieldStruct(name+"0", func(d *decode.D) {
d.FieldU8("version")
})
d.FieldStruct(name+"1", func(d *decode.D) {
d.FieldU32("time")
d.FieldU32("zero") // TODO: does not seems to be zero sometimes?
d.FieldRawLen("random", 1528*8)
})
d.FieldStruct(name+"2", func(d *decode.D) {
d.FieldU32("time")
d.FieldU32("time2")
d.FieldRawLen("random", 1528*8)
})
})
type messageHeader struct {
timestamp uint64
timestampDelta uint64
messageStreamID uint64
messageLength uint64
messageTypeID uint64
}
type message struct {
l uint64
b bytes.Buffer
typ uint64
}
type chunkStream struct {
messageSteams map[uint64]*message
prevHeader messageHeader
}
chunkStreams := map[uint64]*chunkStream{}
messages := d.FieldArrayValue("messages")
d.FieldArray("chunks", func(d *decode.D) {
for !d.End() {
d.FieldStruct("chunk", func(d *decode.D) {
var chunkSteamID uint64
fmt := d.FieldU2("fmt")
switch d.PeekUintBits(6) {
case 0:
// 64-319: 2 byte
d.FieldU6("chunk_stream_id_prefix")
chunkSteamID = d.FieldU8("chunk_stream_id", scalar.UintActualAdd(64))
case 1:
// 64-65599: 3 byte
d.FieldU6("chunk_stream_id_prefix")
chunkSteamID = d.FieldU16("chunk_stream_id", scalar.UintActualAdd(64))
default:
// 2-63: 1 byte
chunkSteamID = d.FieldU6("chunk_stream_id")
}
cs, ok := chunkStreams[chunkSteamID]
if !ok {
cs = &chunkStream{
messageSteams: map[uint64]*message{},
}
chunkStreams[chunkSteamID] = cs
}
var h messageHeader
switch fmt {
case 0:
h.timestamp = d.FieldU24("timestamp", timestampUintDescription)
h.messageLength = d.FieldU24("message_length")
h.messageTypeID = d.FieldU8("message_type_id", rtmpMessageTypeIDNames)
h.messageStreamID = d.FieldU32LE("message_stream_id")
if h.timestamp == timestampExtended {
h.timestamp = d.FieldU32("extended_timestamp")
}
case 1:
h.timestampDelta = d.FieldU24("timestamp_delta", timestampUintDescription)
h.messageLength = d.FieldU24("message_length")
h.messageTypeID = d.FieldU8("message_type_id", rtmpMessageTypeIDNames)
if h.timestamp == timestampExtended {
h.timestampDelta = d.FieldU32("extended_timestamp")
}
h.timestamp = cs.prevHeader.timestamp
h.messageStreamID = cs.prevHeader.messageStreamID
d.FieldValueUint("message_stream_id", h.messageStreamID, scalar.UintDescription("previous"))
case 2:
h.timestampDelta = d.FieldU24("timestamp_delta", timestampUintDescription)
if h.timestamp == timestampExtended {
h.timestampDelta = d.FieldU32("extended_timestamp")
}
h.timestamp = cs.prevHeader.timestamp
h.messageLength = cs.prevHeader.messageLength
h.messageStreamID = cs.prevHeader.messageStreamID
h.messageTypeID = cs.prevHeader.messageTypeID
d.FieldValueUint("message_length", h.messageLength, scalar.UintDescription("previous"))
d.FieldValueUint("message_type_id", h.messageTypeID, scalar.UintDescription("previous"))
d.FieldValueUint("message_stream_id", h.messageStreamID, scalar.UintDescription("previous"))
case 3:
h.timestamp = cs.prevHeader.timestamp
h.timestampDelta = cs.prevHeader.timestampDelta
h.messageLength = cs.prevHeader.messageLength
h.messageStreamID = cs.prevHeader.messageStreamID
h.messageTypeID = cs.prevHeader.messageTypeID
d.FieldValueUint("message_length", h.messageLength, scalar.UintDescription("previous"))
d.FieldValueUint("message_type_id", h.messageTypeID, scalar.UintDescription("previous"))
d.FieldValueUint("message_stream_id", h.messageStreamID, scalar.UintDescription("previous"))
}
h.timestamp += h.timestampDelta
d.FieldValueUint("calculated_timestamp", h.timestamp)
m, ok := cs.messageSteams[h.messageStreamID]
if !ok {
m = &message{
l: h.messageLength,
typ: h.messageTypeID,
}
cs.messageSteams[h.messageStreamID] = m
}
payloadLength := int64(chunkSize)
messageLeft := int64(m.l) - int64(m.b.Len())
if messageLeft < payloadLength {
payloadLength = messageLeft
}
// support decoding interrupted rtmp stream
// TODO: throw away message buffer? currently only do tcp so no point?
payloadLength *= 8
if payloadLength > d.BitsLeft() {
payloadLength = d.BitsLeft()
}
if payloadLength > 0 {
d.CopyBits(&m.b, d.FieldRawLen("data", payloadLength))
}
if m.l == uint64(m.b.Len()) {
messageBR := bitio.NewBitReader(m.b.Bytes(), -1)
messages.FieldStructRootBitBufFn("message", messageBR, func(d *decode.D) {
d.FieldValueUint("message_stream_id", h.messageStreamID)
d.FieldValueUint("message_type_id", m.typ, rtmpMessageTypeIDNames)
rtmpDecodeMessageType(d, int(m.typ), &chunkSize)
})
// delete so that we create a new message{} with a new bytes.Buffer to
// not share byte slice
delete(cs.messageSteams, h.messageStreamID)
}
cs.prevHeader = h
})
}
})
return nil
}