Add RTMP server and publish to RMTP logic

pkg/rtmp/server.go

@@ -0,0 +1,167 @@
+package rtmp
+
+import (
+	"bufio"
+	"encoding/binary"
+	"fmt"
+	"io"
+	"net"
+
+	"github.com/AlexxIT/go2rtc/pkg/core"
+	"github.com/AlexxIT/go2rtc/pkg/flv/amf"
+)
+
+func NewServer(conn net.Conn) (*Conn, error) {
+	c := &Conn{
+		conn: conn,
+		rd:   bufio.NewReaderSize(conn, core.BufferSize),
+		wr:   conn,
+
+		chunks: map[uint8]*header{},
+
+		rdPacketSize: 128,
+		wrPacketSize: 4096,
+	}
+
+	if err := c.serverHandshake(); err != nil {
+		return nil, err
+	}
+	if err := c.writePacketSize(); err != nil {
+		return nil, err
+	}
+
+	return c, nil
+}
+
+func (c *Conn) serverHandshake() error {
+	b := make([]byte, 1+1536)
+	// read C0+C1
+	if _, err := io.ReadFull(c.rd, b); err != nil {
+		return err
+	}
+	// write S0+S1, skip random
+	if _, err := c.conn.Write(b); err != nil {
+		return err
+	}
+	// read S1, skip check
+	if _, err := io.ReadFull(c.rd, make([]byte, 1536)); err != nil {
+		return err
+	}
+	// write C1
+	if _, err := c.conn.Write(b[1:]); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (c *Conn) ReadCommands() error {
+	for {
+		msgType, _, b, err := c.readMessage()
+		if err != nil {
+			return err
+		}
+
+		//log.Printf("%d %.256x", msgType, b)
+
+		switch msgType {
+		case TypeSetPacketSize:
+			c.rdPacketSize = binary.BigEndian.Uint32(b)
+		case TypeCommand:
+			if err = c.acceptCommand(b); err != nil {
+				return err
+			}
+
+			if c.Intent != "" {
+				return nil
+			}
+		}
+	}
+}
+
+const (
+	CommandConnect       = "connect"
+	CommandReleaseStream = "releaseStream"
+	CommandCreateStream  = "createStream"
+	CommandPublish       = "publish"
+	CommandPlay          = "play"
+)
+
+func (c *Conn) acceptCommand(b []byte) error {
+	items, err := amf.NewReader(b).ReadItems()
+	if err != nil {
+		return nil
+	}
+
+	//log.Printf("%#v", items)
+
+	if len(items) < 2 {
+		return fmt.Errorf("rtmp: read command %x", b)
+	}
+
+	cmd, ok := items[0].(string)
+	if !ok {
+		return fmt.Errorf("rtmp: read command %x", b)
+	}
+
+	tID, ok := items[1].(float64) // transaction ID
+	if !ok {
+		return fmt.Errorf("rtmp: read command %x", b)
+	}
+
+	switch cmd {
+	case CommandConnect:
+		if len(items) == 3 {
+			if v, ok := items[2].(map[string]any); ok {
+				c.App, _ = v["app"].(string)
+			}
+		}
+
+		if c.App == "" {
+			return fmt.Errorf("rtmp: read command %x", b)
+		}
+
+		payload := amf.EncodeItems(
+			"_result", tID,
+			map[string]any{
+				"fmsVer": "FMS/3,0,1,123",
+			},
+			map[string]any{
+				"code": "NetConnection.Connect.Success",
+			},
+		)
+		return c.writeMessage(3, TypeCommand, 0, payload)
+
+	case CommandReleaseStream:
+		payload := amf.EncodeItems("_result", tID, nil)
+		return c.writeMessage(3, TypeCommand, 0, payload)
+
+	case CommandCreateStream:
+		payload := amf.EncodeItems("_result", tID, nil, 1)
+		return c.writeMessage(3, TypeCommand, 0, payload)
+
+	case CommandPublish, CommandPlay:
+		c.Intent = cmd
+
+	default:
+		println("rtmp: unknown command: " + cmd)
+	}
+
+	return nil
+}
+
+func (c *Conn) WritePlayStart() error {
+	payload := amf.EncodeItems("onStatus", 0, nil, map[string]any{
+		"code": "NetStream.Play.Start",
+	})
+	return c.writeMessage(3, TypeCommand, 0, payload)
+}
+
+func (c *Conn) code() string {
+	switch c.Intent {
+	case CommandPlay:
+		return "NetStream.Play.Start"
+	case CommandPublish:
+		return "NetStream.Publish.Start"
+	}
+	return ""
+}