diff --git a/dialer.go b/dialer.go
index 4c17b32..50733b3 100644
--- a/dialer.go
+++ b/dialer.go
@@ -14,9 +14,6 @@ type Dialer interface {
 	// Dial connects to the given address via the proxy.
 	Dial(network, addr string) (c net.Conn, err error)
 
-	// DialUDP returns a UDP PacketConn
-	DialUDP(network, addr string) (c net.PacketConn, err error)
-
 	// Get the dialer by dstAddr
 	NextDialer(dstAddr string) Dialer
 }
diff --git a/direct.go b/direct.go
index a83a2a9..33013e7 100644
--- a/direct.go
+++ b/direct.go
@@ -3,8 +3,7 @@ package main
 import "net"
 
 // direct proxy
-type direct struct {
-}
+type direct struct{}
 
 // Direct proxy
 var Direct = &direct{}
@@ -12,6 +11,10 @@ var Direct = &direct{}
 func (d *direct) Addr() string { return "DIRECT" }
 
 func (d *direct) Dial(network, addr string) (net.Conn, error) {
+	if network == "uot" {
+		network = "udp"
+	}
+
 	c, err := net.Dial(network, addr)
 	if c, ok := c.(*net.TCPConn); ok {
 		c.SetKeepAlive(true)
@@ -19,14 +22,4 @@ func (d *direct) Dial(network, addr string) (net.Conn, error) {
 	return c, err
 }
 
-func (d *direct) DialUDP(network, addr string) (net.PacketConn, error) {
-	uAddr, err := net.ResolveUDPAddr(network, addr)
-	if err != nil {
-		logf("ResolveUDPAddr error: %s", err)
-		return nil, err
-	}
-
-	return net.DialUDP("udp", nil, uAddr)
-}
-
 func (d *direct) NextDialer(dstAddr string) Dialer { return d }
diff --git a/http.go b/http.go
index 1beb95e..335a569 100644
--- a/http.go
+++ b/http.go
@@ -236,11 +236,6 @@ func (s *HTTP) Dial(network, addr string) (net.Conn, error) {
 	return nil, errors.New("proxy-http cound not connect remote address: " + addr + ". error code: " + code)
 }
 
-// DialUDP .
-func (s *HTTP) DialUDP(network, addr string) (net.PacketConn, error) {
-	return nil, errors.New("proxy-http udp not supported by http proxy now")
-}
-
 // parseFirstLine parses "GET /foo HTTP/1.1" OR "HTTP/1.1 200 OK" into its three parts.
 func parseFirstLine(tp *textproto.Reader) (r1, r2, r3 string, ok bool) {
 	line, err := tp.ReadLine()
diff --git a/rule.go b/rule.go
index ad9d186..3102909 100644
--- a/rule.go
+++ b/rule.go
@@ -113,11 +113,6 @@ func (rd *RuleDialer) Dial(network, addr string) (net.Conn, error) {
 	return rd.NextDialer(addr).Dial(network, addr)
 }
 
-// DialUDP .
-func (rd *RuleDialer) DialUDP(network, addr string) (net.PacketConn, error) {
-	return rd.NextDialer(addr).DialUDP(network, addr)
-}
-
 // AddDomainIP used to update ipMap rules according to domainMap rule
 func (rd *RuleDialer) AddDomainIP(domain, ip string) error {
 	if ip != "" {
diff --git a/socks5.go b/socks5.go
index bad9425..3e686fd 100644
--- a/socks5.go
+++ b/socks5.go
@@ -156,11 +156,6 @@ func (s *SOCKS5) Dial(network, addr string) (net.Conn, error) {
 	return c, nil
 }
 
-// DialUDP .
-func (s *SOCKS5) DialUDP(network, addr string) (net.PacketConn, error) {
-	return nil, errors.New("udp not supported by socks5 proxy now")
-}
-
 // connect takes an existing connection to a socks5 proxy server,
 // and commands the server to extend that connection to target,
 // which must be a canonical address with a host and port.
diff --git a/ss.go b/ss.go
index f31a949..3674b87 100644
--- a/ss.go
+++ b/ss.go
@@ -207,6 +207,11 @@ func (s *SS) ListenAndServeUDP() {
 
 }
 
+// ListCipher .
+func ListCipher() string {
+	return strings.Join(core.ListCipher(), " ")
+}
+
 // Dial connects to the address addr on the network net via the proxy.
 func (s *SS) Dial(network, addr string) (net.Conn, error) {
 	target := ParseAddr(addr)
@@ -216,12 +221,12 @@ func (s *SS) Dial(network, addr string) (net.Conn, error) {
 
 	switch network {
 	case "tcp":
-		return s.DialTCP(target)
-	case "udp":
+		return s.dialTCP(target)
+	case "uot":
 		target[0] = target[0] | 0x8
-		return s.DialTCP(target)
-	// case "udp":
-	// 	return s.DialUDP(target)
+		return s.dialTCP(target)
+	case "udp":
+		return s.dialUDP(target)
 	default:
 		return nil, errors.New("Unknown schema: " + network)
 	}
@@ -229,7 +234,7 @@ func (s *SS) Dial(network, addr string) (net.Conn, error) {
 }
 
 // DialTCP connects to the address addr via the proxy.
-func (s *SS) DialTCP(target Addr) (net.Conn, error) {
+func (s *SS) dialTCP(target Addr) (net.Conn, error) {
 	c, err := s.cDialer.Dial("tcp", s.addr)
 	if err != nil {
 		logf("dial to %s error: %s", s.addr, err)
@@ -249,20 +254,58 @@ func (s *SS) DialTCP(target Addr) (net.Conn, error) {
 	return c, err
 }
 
-// DialUDP .
-func (s *SS) DialUDP(network, addr string) (net.PacketConn, error) {
-	target := ParseAddr(addr)
-	if target == nil {
-		return nil, errors.New("Unable to parse address: " + addr)
+// TODO: support forwarder chain
+func (s *SS) dialUDP(target Addr) (net.Conn, error) {
+	c, err := net.ListenPacket("udp", "")
+	if err != nil {
+		logf("proxy-ss dialudp failed to listen packet: %v", err)
+		return nil, err
 	}
 
-	c, _ := net.ListenPacket(network, "")
-	c = s.PacketConn(c)
+	sUDPAddr, err := net.ResolveUDPAddr("udp", s.Addr())
+	suc := &ssUDPConn{
+		PacketConn: s.PacketConn(c),
+		addr:       sUDPAddr,
+		target:     target,
+	}
 
-	return c, nil
+	return suc, err
 }
 
-// ListCipher .
-func ListCipher() string {
-	return strings.Join(core.ListCipher(), " ")
+type ssUDPConn struct {
+	net.PacketConn
+
+	addr   net.Addr
+	target Addr
+}
+
+func (uc *ssUDPConn) Read(b []byte) (int, error) {
+	buf := make([]byte, len(b))
+	n, raddr, err := uc.PacketConn.ReadFrom(buf)
+	if err != nil {
+		return 0, err
+	}
+
+	srcAddr := ParseAddr(raddr.String())
+	copy(b, buf[len(srcAddr):])
+
+	return n - len(srcAddr), err
+}
+
+func (uc *ssUDPConn) Write(b []byte) (int, error) {
+	buf := make([]byte, len(uc.target)+len(b))
+	copy(buf, uc.target)
+	copy(buf[len(uc.target):], b)
+
+	// logf("Write: \n%s", hex.Dump(buf))
+
+	return uc.PacketConn.WriteTo(buf, uc.addr)
+}
+
+func (uc *ssUDPConn) WriteTo(b []byte, addr net.Addr) (int, error) {
+	return 0, errors.New("not available")
+}
+
+func (uc *ssUDPConn) RemoteAddr() net.Addr {
+	return uc.addr
 }
diff --git a/strategy.go b/strategy.go
index 2852dcc..1af69d0 100644
--- a/strategy.go
+++ b/strategy.go
@@ -67,10 +67,6 @@ func (rr *rrDialer) Dial(network, addr string) (net.Conn, error) {
 	return rr.NextDialer(addr).Dial(network, addr)
 }
 
-func (rr *rrDialer) DialUDP(network, addr string) (net.PacketConn, error) {
-	return rr.NextDialer(addr).DialUDP(network, addr)
-}
-
 func (rr *rrDialer) NextDialer(dstAddr string) Dialer {
 	n := len(rr.dialers)
 	if n == 1 {
diff --git a/udptun.go b/udptun.go
index e21dcc9..46990b8 100644
--- a/udptun.go
+++ b/udptun.go
@@ -2,7 +2,6 @@ package main
 
 import (
 	"net"
-	"time"
 )
 
 // UDPTun struct
@@ -35,18 +34,7 @@ func (s *UDPTun) ListenAndServe() {
 
 	logf("proxy-udptun listening UDP on %s", s.addr)
 
-	if s.sDialer.Addr() == "DIRECT" {
-		s.ServeDirect(c)
-	} else {
-		s.ServeSS(c)
-	}
-
-}
-
-// ServeDirect .
-func (s *UDPTun) ServeDirect(c net.PacketConn) {
 	buf := make([]byte, udpBufSize)
-
 	for {
 		n, clientAddr, err := c.ReadFrom(buf)
 		if err != nil {
@@ -57,57 +45,26 @@ func (s *UDPTun) ServeDirect(c net.PacketConn) {
 		rc, err := s.sDialer.Dial("udp", s.raddr)
 		if err != nil {
 			logf("proxy-udptun failed to connect to server %v: %v", s.raddr, err)
-			return
-		}
-
-		if urc, ok := rc.(*net.UDPConn); ok {
-			urc.Write(buf[:n])
-			go func() {
-				timedCopy(c, clientAddr, urc, 5*time.Minute, false)
-				urc.Close()
-			}()
-		}
-
-		logf("proxy-udptun %s <-> %s", clientAddr, s.raddr)
-	}
-}
-
-// ServeSS .
-func (s *UDPTun) ServeSS(c net.PacketConn) {
-	// var nm sync.Map
-	buf := make([]byte, udpBufSize)
-	tgt := ParseAddr(s.raddr)
-	copy(buf, tgt)
-
-	for {
-		n, clientAddr, err := c.ReadFrom(buf[len(tgt):])
-		if err != nil {
-			logf("proxy-udptun read error: %v", err)
 			continue
 		}
 
-		go func() {
-			rc, err := s.sDialer.DialUDP("udp", s.raddr)
-			if err != nil {
-				logf("proxy-udptun failed to connect to server %v: %v", s.raddr, err)
-				return
-			}
+		n, err = rc.Write(buf[:n])
+		if err != nil {
+			logf("proxy-udptun rc.Write error: %v", err)
+			continue
+		}
 
-			// TODO: check here, get the correct sDialer's addr
-			sUDPAddr, err := net.ResolveUDPAddr("udp", s.sDialer.Addr())
-			if err != nil {
-				logf("proxy-udptun failed to ResolveUDPAddr %s", s.sDialer.Addr())
-				return
-			}
+		buf = make([]byte, udpBufSize)
+		n, err = rc.Read(buf)
+		if err != nil {
+			logf("proxy-udptun rc.Read error: %v", err)
+			continue
+		}
+		rc.Close()
 
-			rc.WriteTo(buf[:len(tgt)+n], sUDPAddr)
+		// logf("rc resp: \n%s", hex.Dump(buf[:n]))
 
-			go func() {
-				timedCopy(c, clientAddr, rc, 5*time.Minute, false)
-				rc.Close()
-			}()
-
-			logf("proxy-udptun %s <-> %s", clientAddr, s.raddr)
-		}()
+		c.WriteTo(buf[:n], clientAddr)
+		logf("proxy-udptun %s <-> %s", clientAddr, s.raddr)
 	}
 }
diff --git a/uottun.go b/uottun.go
index fabf99a..a87c886 100644
--- a/uottun.go
+++ b/uottun.go
@@ -45,34 +45,32 @@ func (s *UoTTun) ListenAndServe() {
 			continue
 		}
 
-		go func() {
-			rc, err := s.sDialer.Dial("udp", s.raddr)
+		rc, err := s.sDialer.Dial("uot", s.raddr)
+		if err != nil {
+			logf("proxy-uottun failed to connect to server %v: %v", s.raddr, err)
+			return
+		}
+
+		rc.Write(buf[:n])
+
+		// no remote forwarder, just a local udp forwarder
+		if urc, ok := rc.(*net.UDPConn); ok {
+
+			go func() {
+				timedCopy(c, clientAddr, urc, 5*time.Minute, false)
+				urc.Close()
+			}()
+
+		} else { // remote forwarder, udp over tcp
+			resp, err := ioutil.ReadAll(rc)
 			if err != nil {
-				logf("proxy-uottun failed to connect to server %v: %v", s.raddr, err)
+				logf("error in ioutil.ReadAll: %s\n", err)
 				return
 			}
+			rc.Close()
+			c.WriteTo(resp, clientAddr)
+		}
 
-			rc.Write(buf[:n])
-
-			// no remote forwarder, just a local udp forwarder
-			if urc, ok := rc.(*net.UDPConn); ok {
-
-				go func() {
-					timedCopy(c, clientAddr, urc, 5*time.Minute, false)
-					urc.Close()
-				}()
-
-			} else { // remote forwarder, udp over tcp
-				resp, err := ioutil.ReadAll(rc)
-				if err != nil {
-					logf("error in ioutil.ReadAll: %s\n", err)
-					return
-				}
-				rc.Close()
-				c.WriteTo(resp, clientAddr)
-			}
-
-			logf("proxy-uottun %s <-> %s", clientAddr, s.raddr)
-		}()
+		logf("proxy-uottun %s <-> %s", clientAddr, s.raddr)
 	}
 }