diff --git a/proxy/vmess/client.go b/proxy/vmess/client.go
index b22a89a..c8abcda 100644
--- a/proxy/vmess/client.go
+++ b/proxy/vmess/client.go
@@ -129,29 +129,12 @@ func (c *Client) EncodeRequest() ([]byte, error) {
 	fnv1a.Write(buf.Bytes())
 	buf.Write(fnv1a.Sum(nil))
 
-	// AES-128-CFB crypt the request：
-	// Key：MD5(UUID + []byte('c48619fe-8f02-49e0-b9e9-edf763e17e21'))
-	// IV：MD5(X + X + X + X)，X = []byte(timestamp.now) (8 bytes, Big Endian)
-	md5hash := md5.New()
-	md5hash.Write(c.user.UUID[:])
-	md5hash.Write([]byte("c48619fe-8f02-49e0-b9e9-edf763e17e21"))
-	key := md5hash.Sum(nil)
-
-	md5hash.Reset()
-	ts := make([]byte, 8)
-	binary.BigEndian.PutUint64(ts, uint64(time.Now().UTC().Unix()))
-	md5hash.Write(ts)
-	md5hash.Write(ts)
-	md5hash.Write(ts)
-	md5hash.Write(ts)
-	iv := md5hash.Sum(nil)
-
-	block, err := aes.NewCipher(key)
+	block, err := aes.NewCipher(c.user.CmdKey[:])
 	if err != nil {
 		return nil, err
 	}
 
-	stream := cipher.NewCFBEncrypter(block, iv)
+	stream := cipher.NewCFBEncrypter(block, TimestampHash(time.Now().UTC()))
 	stream.XORKeyStream(buf.Bytes(), buf.Bytes())
 
 	return buf.Bytes(), nil
diff --git a/proxy/vmess/user.go b/proxy/vmess/user.go
index 4fb4c4e..bd57b9a 100644
--- a/proxy/vmess/user.go
+++ b/proxy/vmess/user.go
@@ -1,14 +1,18 @@
 package vmess
 
 import (
+	"crypto/md5"
+	"encoding/binary"
 	"encoding/hex"
 	"errors"
 	"strings"
+	"time"
 )
 
 // User of vmess client
 type User struct {
-	UUID [16]byte
+	UUID   [16]byte
+	CmdKey [16]byte
 }
 
 // NewUser .
@@ -18,9 +22,8 @@ func NewUser(uuidStr string) (*User, error) {
 		return nil, err
 	}
 
-	u := &User{
-		UUID: uuid,
-	}
+	u := &User{UUID: uuid}
+	copy(u.CmdKey[:], GetKey(uuid))
 
 	return u, nil
 }
@@ -35,3 +38,26 @@ func StrToUUID(s string) (uuid [16]byte, err error) {
 	_, err = hex.Decode(uuid[:], b)
 	return
 }
+
+// GetKey returns the key of AES-128-CFB encrypter
+// Key：MD5(UUID + []byte('c48619fe-8f02-49e0-b9e9-edf763e17e21'))
+func GetKey(uuid [16]byte) []byte {
+	md5hash := md5.New()
+	md5hash.Write(uuid[:])
+	md5hash.Write([]byte("c48619fe-8f02-49e0-b9e9-edf763e17e21"))
+	return md5hash.Sum(nil)
+}
+
+// TimestampHash returns the iv of AES-128-CFB encrypter
+// IV：MD5(X + X + X + X)，X = []byte(timestamp.now) (8 bytes, Big Endian)
+func TimestampHash(t time.Time) []byte {
+	md5hash := md5.New()
+
+	ts := make([]byte, 8)
+	binary.BigEndian.PutUint64(ts, uint64(t.UTC().Unix()))
+	md5hash.Write(ts)
+	md5hash.Write(ts)
+	md5hash.Write(ts)
+	md5hash.Write(ts)
+	return md5hash.Sum(nil)
+}
diff --git a/proxy/vmess/vmess.go b/proxy/vmess/vmess.go
index 0a78ddd..1dc43f6 100644
--- a/proxy/vmess/vmess.go
+++ b/proxy/vmess/vmess.go
@@ -90,9 +90,7 @@ func (s *VMess) Dial(network, addr string) (net.Conn, error) {
 		return nil, err
 	}
 
-	rc, err = client.NewConn(rc)
-
-	return rc, nil
+	return client.NewConn(rc)
 }
 
 // DialUDP connects to the given address via the proxy.