Add Socks5 support

internal/http/tgt_parser.go

@@ -72,16 +72,10 @@ func (c *conn) Write(b []byte) (n int, err error) {
 }
 
 // ParseAddr parse target addr from net.Conn
-func ParseAddr(conn net.Conn, password []byte) (c net.Conn, domain string, port uint16, err error) {
+func ParseAddr(conn net.Conn, password []byte) (_ net.Conn, domain string, port uint16, err error) {
 	teeConn := &util.TeeConn{Conn: conn}
 	teeConn.StartOrReset()
-	defer func() {
-		if err != nil {
-			teeConn.Close()
-		} else {
-			teeConn.Stop()
-		}
-	}()
+	defer teeConn.Stop()
 
 	head := new(header)
 	if err = binary.Read(conn, binary.BigEndian, head); err != nil {
@@ -102,37 +96,40 @@ func ParseAddr(conn net.Conn, password []byte) (c net.Conn, domain string, port
 
 	case TGT_HTTP:
 		teeConn.DropAndRestart()
-
-		var resp *http.Request
-		resp, err = http.ReadRequest(bufio.NewReader(teeConn))
-		if err != nil {
-			return nil, "", 0, err
-		}
-
-		idx := strings.LastIndex(resp.Host, ":")
-		if idx == -1 {
-			return teeConn, resp.Host, 80, nil
-		}
-
-		var port uint64
-		if port, err = strconv.ParseUint(resp.Host[idx+1:], 10, 16); err != nil {
-			return nil, "", 0, err
-		}
-		return teeConn, resp.Host[:idx], uint16(port), nil
+		return ParseHTTP(teeConn)
 
 	case TGT_HTTPS:
 		teeConn.DropAndRestart()
-
-		domain, _, err := extractSNI(teeConn)
-		if err != nil {
-			return nil, "", 0, err
-		}
-		return teeConn, domain, head.Port, nil
+		conn, domain, err = ParseHTTPS(teeConn)
+		return conn, domain, head.Port, err
 
 	default:
-		return nil, "", 0, errors.New("invalid request")
+		return teeConn, "", 0, errors.New("invalid request")
 	}
 }
+func ParseHTTP(teeConn net.Conn) (_ net.Conn, domain string, port uint16, err error) {
+	resp, err := http.ReadRequest(bufio.NewReader(teeConn))
+	if err != nil {
+		return teeConn, "", 0, err
+	}
+
+	idx := strings.LastIndex(resp.Host, ":")
+	if idx == -1 {
+		return teeConn, resp.Host, 80, nil
+	}
+
+	p, err := strconv.ParseUint(resp.Host[idx+1:], 10, 16)
+	if err != nil {
+		return teeConn, "", 0, err
+	}
+	return teeConn, resp.Host[:idx], uint16(p), nil
+}
+func ParseHTTPS(teeConn net.Conn) (_ net.Conn, domain string, err error) {
+	if domain, _, err = extractSNI(teeConn); err != nil {
+		return nil, "", err
+	}
+	return teeConn, domain, nil
+}
 
 var errChecksum = errors.New("invalid checksum")
 

internal/socks5/rfc_def.go

@@ -0,0 +1,44 @@
+package socks5
+
+// https://tools.ietf.org/html/rfc1928
+
+type authReq struct {
+	VER      byte
+	NMETHODS byte
+	METHODS  [1]byte // 1 to 255, fix to no authentication
+}
+
+type authResp struct {
+	VER    byte
+	METHOD byte
+}
+
+type request struct {
+	req
+	DST_ADDR []byte // first byte is length
+	DST_PORT []byte // two bytes
+}
+type req struct {
+	VER  byte
+	CMD  byte
+	RSV  byte
+	ATYP byte
+}
+
+func (r *request) Bytes() []byte {
+	out := []byte{r.VER, r.CMD, r.RSV, r.ATYP}
+	out = append(out, r.DST_ADDR...)
+	return append(out, r.DST_PORT...)
+}
+
+type response struct {
+	resp
+	DST_ADDR []byte // first byte is length
+	DST_PORT []byte // two bytes
+}
+type resp struct {
+	VER  byte
+	REP  byte
+	RSV  byte
+	ATYP byte
+}

internal/socks5/socks5.go

@@ -5,13 +5,28 @@ import (
 	"fmt"
 	"io"
 	"net"
-	"strconv"
+	"strings"
 )
 
-func ToSocks5(c net.Conn, domain, port string) net.Conn {
-	num, _ := strconv.Atoi(port)
-	bytes := []byte{byte(num >> 8), byte(num)}
-	return &conn{init: make(chan struct{}), Conn: c, domain: domain, port: bytes}
+func IsSocks5Schema(addr string) (string, bool) {
+	if strings.HasPrefix(addr, "socks5://") {
+		return strings.TrimPrefix(addr, "socks5://"), true
+	}
+
+	if strings.HasPrefix(addr, "socks5h://") {
+		return strings.TrimPrefix(addr, "socks5h://"), true
+	}
+
+	return addr, false
+}
+
+func ToSocks5(c net.Conn, domain string, port uint16) net.Conn {
+	return &conn{
+		init:   make(chan struct{}),
+		Conn:   c,
+		domain: domain,
+		port:   []byte{byte(port >> 8), byte(port)},
+	}
 }
 
 type conn struct {
@@ -106,44 +121,3 @@ func (c *conn) Write(b []byte) (n int, err error) {
 	close(c.init)
 	return c.Conn.Write(b)
 }
-
-type authReq struct {
-	VER      byte
-	NMETHODS byte
-	METHODS  [1]byte // 1 to 255, fix to no authentication
-}
-
-type authResp struct {
-	VER    byte
-	METHOD byte
-}
-
-type request struct {
-	req
-	DST_ADDR []byte // first byte is length
-	DST_PORT []byte // two bytes
-}
-type req struct {
-	VER  byte
-	CMD  byte
-	RSV  byte
-	ATYP byte
-}
-
-func (r *request) Bytes() []byte {
-	out := []byte{r.VER, r.CMD, r.RSV, r.ATYP}
-	out = append(out, r.DST_ADDR...)
-	return append(out, r.DST_PORT...)
-}
-
-type response struct {
-	resp
-	DST_ADDR []byte // first byte is length
-	DST_PORT []byte // two bytes
-}
-type resp struct {
-	VER  byte
-	REP  byte
-	RSV  byte
-	ATYP byte
-}