From 984bf27d9b0bd1193acc1921652e18c9e1b10aea Mon Sep 17 00:00:00 2001
From: wwqgtxx <wwqgtxx@gmail.com>
Date: Sat, 20 May 2023 18:35:04 +0800
Subject: [PATCH] chore: using internal socks5.ReadAddr0 in trojan

---
 listener/shadowsocks/tcp.go |  2 +-
 transport/socks5/socks5.go  | 44 +++++++++++++++++++++++++++++++++++++
 transport/trojan/trojan.go  |  3 +--
 3 files changed, 46 insertions(+), 3 deletions(-)

diff --git a/listener/shadowsocks/tcp.go b/listener/shadowsocks/tcp.go
index 6884b960..febf87c3 100644
--- a/listener/shadowsocks/tcp.go
+++ b/listener/shadowsocks/tcp.go
@@ -103,7 +103,7 @@ func (l *Listener) HandleConn(conn net.Conn, in chan<- C.ConnContext, additions
 	conn = l.pickCipher.StreamConn(conn)
 	conn = N.NewDeadlineConn(conn) // embed ss can't handle readDeadline correctly
 
-	target, err := socks5.ReadAddr(conn, make([]byte, socks5.MaxAddrLen))
+	target, err := socks5.ReadAddr0(conn)
 	if err != nil {
 		_ = conn.Close()
 		return
diff --git a/transport/socks5/socks5.go b/transport/socks5/socks5.go
index 7d4f11ae..6f95cce9 100644
--- a/transport/socks5/socks5.go
+++ b/transport/socks5/socks5.go
@@ -299,6 +299,50 @@ func ReadAddr(r io.Reader, b []byte) (Addr, error) {
 	return nil, ErrAddressNotSupported
 }
 
+func ReadAddr0(r io.Reader) (Addr, error) {
+	aType, err := ReadByte(r) // read 1st byte for address type
+	if err != nil {
+		return nil, err
+	}
+
+	switch aType {
+	case AtypDomainName:
+		var domainLength byte
+		domainLength, err = ReadByte(r) // read 2nd byte for domain length
+		if err != nil {
+			return nil, err
+		}
+		b := make([]byte, 1+1+uint16(domainLength)+2)
+		_, err = io.ReadFull(r, b[2:])
+		b[0] = aType
+		b[1] = domainLength
+		return b, err
+	case AtypIPv4:
+		var b [1 + net.IPv4len + 2]byte
+		_, err = io.ReadFull(r, b[1:])
+		b[0] = aType
+		return b[:], err
+	case AtypIPv6:
+		var b [1 + net.IPv6len + 2]byte
+		_, err = io.ReadFull(r, b[1:])
+		b[0] = aType
+		return b[:], err
+	}
+
+	return nil, ErrAddressNotSupported
+}
+
+func ReadByte(reader io.Reader) (byte, error) {
+	if br, isBr := reader.(io.ByteReader); isBr {
+		return br.ReadByte()
+	}
+	var b [1]byte
+	if _, err := io.ReadFull(reader, b[:]); err != nil {
+		return 0, err
+	}
+	return b[0], nil
+}
+
 // SplitAddr slices a SOCKS address from beginning of b. Returns nil if failed.
 func SplitAddr(b []byte) Addr {
 	addrLen := 1
diff --git a/transport/trojan/trojan.go b/transport/trojan/trojan.go
index 90700491..d37026c1 100644
--- a/transport/trojan/trojan.go
+++ b/transport/trojan/trojan.go
@@ -21,7 +21,6 @@ import (
 	"github.com/Dreamacro/clash/transport/vless"
 	"github.com/Dreamacro/clash/transport/vmess"
 
-	M "github.com/sagernet/sing/common/metadata"
 	xtls "github.com/xtls/go"
 )
 
@@ -358,7 +357,7 @@ func (pc *PacketConn) WaitReadFrom() (data []byte, put func(), addr net.Addr, er
 	pc.mux.Lock()
 	defer pc.mux.Unlock()
 
-	destination, err := M.SocksaddrSerializer.ReadAddrPort(pc.Conn)
+	destination, err := socks5.ReadAddr0(pc.Conn)
 	if err != nil {
 		return nil, nil, nil, err
 	}