diff --git a/packet.go b/packet.go
index db70f51..f2f3dde 100644
--- a/packet.go
+++ b/packet.go
@@ -44,10 +44,10 @@ func NewPacket(destAddr string, data []byte) (p Packet, err error) {
 	if ip := net.ParseIP(host); ip != nil {
 		if ip4 := ip.To4(); ip4 != nil {
 			p.ATYP = ATYPIPv4
-			p.DstAddr.IP = ip4
+			p.DstAddr.IP = ip
 		} else {
 			p.ATYP = ATYPIPV6
-			p.DstAddr.IP = ip.To16()
+			p.DstAddr.IP = ip
 		}
 	} else {
 		if len(host) > math.MaxUint8 {
@@ -57,6 +57,7 @@ func NewPacket(destAddr string, data []byte) (p Packet, err error) {
 		p.ATYP = ATYPDomain
 		p.DstAddr.FQDN = host
 	}
+	p.Data = data
 	return
 }
 
@@ -69,12 +70,15 @@ func (sf *Packet) Parses(b []byte) error {
 	// FRAG
 	sf.Frag = b[2]
 	sf.ATYP = b[3]
+	headLen := 4
 	switch sf.ATYP {
 	case ATYPIPv4:
+		headLen += net.IPv4len + 2
 		sf.DstAddr.IP = net.IPv4(b[4], b[5], b[6], b[7])
 		sf.DstAddr.Port = buildPort(b[4+net.IPv4len], b[4+net.IPv4len+1])
 	case ATYPIPV6:
-		if len(b) <= (4 + net.IPv6len + 2) {
+		headLen += net.IPv6len + 2
+		if len(b) <= headLen {
 			return errors.New("too short")
 		}
 
@@ -82,7 +86,8 @@ func (sf *Packet) Parses(b []byte) error {
 		sf.DstAddr.Port = buildPort(b[4+net.IPv6len], b[4+net.IPv6len+1])
 	case ATYPDomain:
 		addrLen := int(b[4])
-		if len(b) <= (4 + 1 + addrLen + 2) {
+		headLen += 1 + addrLen + 2
+		if len(b) <= headLen {
 			return errors.New("too short")
 		}
 		str := make([]byte, addrLen)
@@ -92,5 +97,25 @@ func (sf *Packet) Parses(b []byte) error {
 	default:
 		return errUnrecognizedAddrType
 	}
+	sf.Data = b[headLen:]
 	return nil
 }
+
+func (sf *Packet) Header() []byte {
+	bs := make([]byte, 0, 32)
+	bs = append(bs, []byte{byte(sf.RSV << 8), byte(sf.RSV), sf.Frag}...)
+	switch sf.ATYP {
+	case ATYPIPv4:
+		bs = append(bs, ATYPIPv4)
+		bs = append(bs, sf.DstAddr.IP...)
+	case ATYPIPV6:
+		bs = append(bs, ATYPIPV6)
+		bs = append(bs, sf.DstAddr.IP...)
+	case ATYPDomain:
+		bs = append(bs, ATYPDomain)
+		bs = append(bs, []byte(sf.DstAddr.FQDN)...)
+	}
+	hi, lo := breakPort(sf.DstAddr.Port)
+	bs = append(bs, hi, lo)
+	return bs
+}
diff --git a/request.go b/request.go
index 48069ea..aeb1aca 100644
--- a/request.go
+++ b/request.go
@@ -286,20 +286,7 @@ func (s *Server) handleAssociate(ctx context.Context, writer io.Writer, req *Req
 						}
 						tmpBufPool := s.bufferPool.Get()
 						proBuf := tmpBufPool
-						proBuf = append(proBuf, []byte{byte(pkb.RSV << 8), byte(pkb.RSV), pkb.Frag}...)
-						hi, lo := breakPort(pkb.DstAddr.Port)
-						switch pkb.ATYP {
-						case ATYPIPv4:
-							proBuf = append(proBuf, ATYPIPv4)
-							proBuf = append(proBuf, pkb.DstAddr.IP...)
-						case ATYPIPV6:
-							proBuf = append(proBuf, ATYPIPV6)
-							proBuf = append(proBuf, pkb.DstAddr.IP...)
-						case ATYPDomain:
-							proBuf = append(proBuf, ATYPDomain)
-							proBuf = append(proBuf, []byte(pkb.DstAddr.FQDN)...)
-						}
-						proBuf = append(proBuf, hi, lo)
+						proBuf = append(proBuf, pkb.Header()...)
 						proBuf = append(proBuf, pkb.Data...)
 						if _, err := bindLn.WriteTo(proBuf, srcAddr); err != nil {
 							s.bufferPool.Put(tmpBufPool)
diff --git a/socks5_test.go b/socks5_test.go
index 9d62dc9..1d44de3 100644
--- a/socks5_test.go
+++ b/socks5_test.go
@@ -137,6 +137,7 @@ func TestSOCKS5_Associate(t *testing.T) {
 			if err != nil {
 				return
 			}
+
 			if !bytes.Equal(buf[:n], []byte("ping")) {
 				t.Fatalf("bad: %v", buf)
 			}