diff --git a/common/conn/conn.go b/common/conn/conn.go
index e33ca6e..34ff05d 100644
--- a/common/conn/conn.go
+++ b/common/conn/conn.go
@@ -9,29 +9,36 @@ import (
 	"github.com/nadoo/glider/common/log"
 )
 
+// UDPBufSize is the size of udp buffer
 const UDPBufSize = 65536
 
+// Conn struct
 type Conn struct {
 	r *bufio.Reader
 	net.Conn
 }
 
+// NewConn .
 func NewConn(c net.Conn) Conn {
 	return Conn{bufio.NewReader(c), c}
 }
 
+// NewConnSize .
 func NewConnSize(c net.Conn, n int) Conn {
 	return Conn{bufio.NewReaderSize(c, n), c}
 }
 
+// Peek .
 func (c Conn) Peek(n int) ([]byte, error) {
 	return c.r.Peek(n)
 }
 
+// Read .
 func (c Conn) Read(p []byte) (int, error) {
 	return c.r.Read(p)
 }
 
+// Relay .
 func Relay(left, right net.Conn) (int64, int64, error) {
 	type res struct {
 		N   int64
diff --git a/common/log/log.go b/common/log/log.go
index ae80f47..edc967f 100644
--- a/common/log/log.go
+++ b/common/log/log.go
@@ -5,12 +5,16 @@ import "log"
 // Func defines a simple log function
 type Func func(f string, v ...interface{})
 
-var F Func
+// F is the main log function
+var F Func = func(f string, v ...interface{}) {
+}
 
+// Fatal log and exit
 func Fatal(v ...interface{}) {
 	log.Fatal(v)
 }
 
+// Fatalf log and exit
 func Fatalf(f string, v ...interface{}) {
 	log.Fatalf(f, v)
 }
diff --git a/common/socks/socks.go b/common/socks/socks.go
index 09f9515..7532402 100644
--- a/common/socks/socks.go
+++ b/common/socks/socks.go
@@ -7,6 +7,7 @@ import (
 	"strconv"
 )
 
+// SOCKS auth type
 const (
 	AuthNone     = 0
 	AuthPassword = 2
@@ -29,6 +30,7 @@ const (
 // MaxAddrLen is the maximum size of SOCKS address in bytes.
 const MaxAddrLen = 1 + 1 + 255 + 2
 
+// Errors are socks5 errors
 var Errors = []error{
 	errors.New(""),
 	errors.New("general failure"),
@@ -42,6 +44,7 @@ var Errors = []error{
 	errors.New("socks5UDPAssociate"),
 }
 
+// Addr .
 type Addr []byte
 
 // String serializes SOCKS address a to string form.
@@ -73,6 +76,7 @@ func ATYP(b byte) int {
 	return int(b &^ 0x8)
 }
 
+// ReadAddrBuf reads just enough bytes from r to get a valid Addr.
 func ReadAddrBuf(r io.Reader, b []byte) (Addr, error) {
 	if len(b) < MaxAddrLen {
 		return nil, io.ErrShortBuffer
diff --git a/main.go b/main.go
index 6fe1c33..e9334c9 100644
--- a/main.go
+++ b/main.go
@@ -1,7 +1,6 @@
 package main
 
 import (
-	stdlog "log"
 	"os"
 	"os/signal"
 	"strings"
@@ -36,11 +35,11 @@ func main() {
 
 	confInit()
 
-	log.F = func(f string, v ...interface{}) {
-		if conf.Verbose {
-			stdlog.Printf(f, v...)
-		}
-	}
+	// log.F = func(f string, v ...interface{}) {
+	// 	if conf.Verbose {
+	// 		stdlog.Printf(f, v...)
+	// 	}
+	// }
 
 	sDialer := NewRuleDialer(conf.rules, dialerFromConf())
 
diff --git a/proxy/dialer.go b/proxy/dialer.go
index b25b3d1..7762b5b 100644
--- a/proxy/dialer.go
+++ b/proxy/dialer.go
@@ -9,7 +9,7 @@ import (
 	"github.com/nadoo/glider/common/log"
 )
 
-// A proxy.Dialer means to establish a connection and relay it.
+// Dialer means to establish a connection and relay it.
 type Dialer interface {
 	// Addr()
 	Addr() string
@@ -24,16 +24,19 @@ type Dialer interface {
 	NextDialer(dstAddr string) Dialer
 }
 
+// DialerCreator is a function to create dialers.
 type DialerCreator func(s string, dialer Dialer) (Dialer, error)
 
 var (
 	dialerMap = make(map[string]DialerCreator)
 )
 
+// RegisterDialer is used to register a dialer
 func RegisterDialer(name string, c DialerCreator) {
 	dialerMap[name] = c
 }
 
+// DialerFromURL calls the registered creator to create dialers.
 func DialerFromURL(s string, dialer Dialer) (Dialer, error) {
 	u, err := url.Parse(s)
 	if err != nil {
diff --git a/proxy/server.go b/proxy/server.go
index 3e7bd60..4bc4e1d 100644
--- a/proxy/server.go
+++ b/proxy/server.go
@@ -14,16 +14,19 @@ type Server interface {
 	ListenAndServe()
 }
 
+// ServerCreator is a function to create proxy servers.
 type ServerCreator func(s string, dialer Dialer) (Server, error)
 
 var (
 	serverMap = make(map[string]ServerCreator)
 )
 
+// RegisterServer is used to register a proxy server
 func RegisterServer(name string, c ServerCreator) {
 	serverMap[name] = c
 }
 
+// ServerFromURL calls the registered creator to create proxy servers.
 func ServerFromURL(s string, dialer Dialer) (Server, error) {
 	if !strings.Contains(s, "://") {
 		s = "mixed://" + s
diff --git a/proxy/socks5/socks5.go b/proxy/socks5/socks5.go
index 2d88581..a76734b 100644
--- a/proxy/socks5/socks5.go
+++ b/proxy/socks5/socks5.go
@@ -26,6 +26,7 @@ import (
 	"github.com/nadoo/glider/proxy"
 )
 
+// Version: socks5 version
 const Version = 5
 
 // SOCKS5 struct