diff --git a/logger/main.go b/logger/main.go
index 869ae02..26229bd 100644
--- a/logger/main.go
+++ b/logger/main.go
@@ -1,17 +1,23 @@
 package main
 
 import (
+	"flag"
 	"github.com/serverwentdown/bypass"
 )
 
+var listen string
+
 func main() {
+	flag.StringVar(&listen, "listen", ":8000", "listen on ip and port")
+	flag.Parse()
+
 	conf := &socks5.Config{}
 	server, err := socks5.New(conf)
 	if err != nil {
 		panic(err)
 	}
 
-	if err := server.ListenAndServe("tcp", "127.0.0.1:8000"); err != nil {
+	if err := server.ListenAndServe("tcp", listen); err != nil {
 		panic(err)
 	}
 }
diff --git a/request.go b/request.go
index c4de7d7..846db74 100644
--- a/request.go
+++ b/request.go
@@ -1,13 +1,14 @@
 package socks5
 
 import (
+	"bytes"
 	"fmt"
 	"io"
+	"log"
+	"math/big"
 	"net"
 	"strconv"
 	"strings"
-	"math/big"
-	"bytes"
 
 	"golang.org/x/net/context"
 )
@@ -372,8 +373,8 @@ func copyAndModify(dst io.Writer, src io.Reader) (written int64, err error) {
 	for {
 		nr, er := src.Read(buf)
 		if written == 0 && nr > 0 {
-			if (buf[0] == 0x16 && buf[5] == 0x01) {// && buf[1] == 0x03 && buf[2] == 0x01) {
-				modifyHello(buf);
+			if buf[0] == 0x16 && buf[5] == 0x01 { // && buf[1] == 0x03 && buf[2] == 0x01) {
+				modifyHello(buf)
 			}
 		}
 		if nr > 0 {
@@ -428,7 +429,7 @@ func modifyHello(buf []byte) {
 
 	// 2 byte cipher suites length (in bytes)
 	suitesLength := big.NewInt(0)
-	suitesLength.SetBytes(buf[44+sessionLength.Uint64():44+sessionLength.Uint64()+2])
+	suitesLength.SetBytes(buf[44+sessionLength.Uint64() : 44+sessionLength.Uint64()+2])
 
 	// cipher suites
 
@@ -438,49 +439,49 @@ func modifyHello(buf []byte) {
 
 	// 2 byte extensions length
 	extensionsLength := big.NewInt(0)
-	extensionsLength.SetBytes(buf[48+sessionLength.Uint64()+suitesLength.Uint64():48+sessionLength.Uint64()+suitesLength.Uint64()+2])
+	extensionsLength.SetBytes(buf[48+sessionLength.Uint64()+suitesLength.Uint64() : 48+sessionLength.Uint64()+suitesLength.Uint64()+2])
 
 	// extensions:
 
 	extensionsStart := 50 + sessionLength.Uint64() + suitesLength.Uint64()
 	extensionsEnd := extensionsStart + extensionsLength.Uint64()
 	cur := extensionsStart
-	for cur + 4 < extensionsEnd {
-		if (buf[cur] != 0x00 || buf[cur + 1] != 0x00) {
+	for cur+4 < extensionsEnd {
+		if buf[cur] != 0x00 || buf[cur+1] != 0x00 {
 			extensionLength := big.NewInt(0)
-			extensionLength.SetBytes(buf[cur+2:cur+4])
+			extensionLength.SetBytes(buf[cur+2 : cur+4])
 			cur += 4 + extensionLength.Uint64()
 			continue
 		}
 
 		// yay is sni header!
 		extensionLength := big.NewInt(0)
-		extensionLength.SetBytes(buf[cur+2:cur+4])
+		extensionLength.SetBytes(buf[cur+2 : cur+4])
 
 		// 2 byte sni list length
 		listLength := big.NewInt(0)
-		listLength.SetBytes(buf[cur+4:cur+6])
+		listLength.SetBytes(buf[cur+4 : cur+6])
 
 		var list []string
 
 		listStart := cur + 6
 		listEnd := cur + 6 + listLength.Uint64()
 		lcur := listStart
-		for lcur + 3 < listEnd {
+		for lcur+3 < listEnd {
 			// 1 byte type
 			// 2 byte length
 			nameLength := big.NewInt(0)
-			nameLength.SetBytes(buf[lcur+1:lcur+3])
+			nameLength.SetBytes(buf[lcur+1 : lcur+3])
 			//buf[lcur+3] = 'x'
 			// name
 			var name bytes.Buffer
-			name.Write(buf[lcur+3:lcur+3+nameLength.Uint64()])
+			name.Write(buf[lcur+3 : lcur+3+nameLength.Uint64()])
 			name.WriteByte(0)
 			// append to list
 			list = append(list, name.String())
 			lcur += 3 + nameLength.Uint64()
 		}
-		fmt.Println(list)
+		log.Println(list)
 
 		break
 	}
@@ -488,5 +489,5 @@ func modifyHello(buf []byte) {
 	//     2 byte extension type
 	//     2 byte extension length
 	//     extension data
-	
+
 }