Code: refresh code

transport/vless/conn.go

@@ -0,0 +1,109 @@
+package vless
+
+import (
+	"bytes"
+	"encoding/binary"
+	"errors"
+	"io"
+	"io/ioutil"
+	"net"
+
+	"github.com/gofrs/uuid"
+)
+
+/*var (
+
+	//proto.Marshal(addons) bytes for Flow: "xtls-rprx-direct"
+	addOnBytes, _ = hex.DecodeString("120a1078746c732d727072782d646972656374")
+	addOnBytesLen = len(addOnBytes)
+
+	//proto.Marshal(addons) bytes for Flow: ""
+	//addOnEmptyBytes, _ = hex.DecodeString("00")
+	//addOnEmptyBytesLen  = len(addOnEmptyBytes)
+)*/
+
+type Conn struct {
+	net.Conn
+	dst *DstAddr
+	id  *uuid.UUID
+
+	received bool
+}
+
+func (vc *Conn) Read(b []byte) (int, error) {
+	if vc.received {
+		return vc.Conn.Read(b)
+	}
+
+	if err := vc.recvResponse(); err != nil {
+		return 0, err
+	}
+	vc.received = true
+	return vc.Conn.Read(b)
+}
+
+func (vc *Conn) sendRequest() error {
+	buf := &bytes.Buffer{}
+
+	buf.WriteByte(Version)   // protocol version
+	buf.Write(vc.id.Bytes()) // 16 bytes of uuid
+
+	// command
+	if vc.dst.UDP {
+		buf.WriteByte(0) // addon data length. 0 means no addon data
+		//buf.WriteByte(byte(addOnEmptyBytesLen))
+		//buf.Write(addOnEmptyBytes)
+		buf.WriteByte(CommandUDP)
+	} else {
+		buf.WriteByte(0) // addon data length. 0 means no addon data
+		//buf.WriteByte(byte(addOnBytesLen))
+		//buf.Write(addOnBytes)
+		buf.WriteByte(CommandTCP)
+	}
+
+	// Port AddrType Addr
+	binary.Write(buf, binary.BigEndian, uint16(vc.dst.Port))
+	buf.WriteByte(vc.dst.AddrType)
+	buf.Write(vc.dst.Addr)
+
+	_, err := vc.Conn.Write(buf.Bytes())
+	return err
+}
+
+func (vc *Conn) recvResponse() error {
+	var err error
+	buf := make([]byte, 1)
+	_, err = io.ReadFull(vc.Conn, buf)
+	if err != nil {
+		return err
+	}
+
+	if buf[0] != Version {
+		return errors.New("unexpected response version")
+	}
+
+	_, err = io.ReadFull(vc.Conn, buf)
+	if err != nil {
+		return err
+	}
+
+	length := int64(buf[0])
+	if length != 0 { // addon data length > 0
+		io.CopyN(ioutil.Discard, vc.Conn, length) // just discard
+	}
+
+	return nil
+}
+
+// newConn return a Conn instance
+func newConn(conn net.Conn, id *uuid.UUID, dst *DstAddr) (*Conn, error) {
+	c := &Conn{
+		Conn: conn,
+		id:   id,
+		dst:  dst,
+	}
+	if err := c.sendRequest(); err != nil {
+		return nil, err
+	}
+	return c, nil
+}