diff --git a/api/api.go b/api/api.go
index 2f803d6..e93975a 100644
--- a/api/api.go
+++ b/api/api.go
@@ -9,7 +9,7 @@ import (
 
 type Handler func(ctx context.Context, auth statistic.Authenticator) error
 
-var handlers = map[string]Handler{}
+var handlers = make(map[string]Handler)
 
 func RegisterHandler(name string, handler Handler) {
 	handlers[name] = handler
diff --git a/api/service/server_test.go b/api/service/server_test.go
index 25bab93..6fa786d 100644
--- a/api/service/server_test.go
+++ b/api/service/server_test.go
@@ -310,8 +310,8 @@ qbPPrmQPgv5prRHCObn0+j6SwV9vV7Q9BI41CloKUDXZmPFTVipP6z5tV2YTOg==
 `
 
 func init() {
-	ioutil.WriteFile("server.crt", []byte(serverCert), 0777)
-	ioutil.WriteFile("server.key", []byte(serverKey), 0777)
-	ioutil.WriteFile("client.crt", []byte(clientCert), 0777)
-	ioutil.WriteFile("client.key", []byte(clientKey), 0777)
+	ioutil.WriteFile("server.crt", []byte(serverCert), 0o777)
+	ioutil.WriteFile("server.key", []byte(serverKey), 0o777)
+	ioutil.WriteFile("client.crt", []byte(clientCert), 0o777)
+	ioutil.WriteFile("client.key", []byte(clientKey), 0o777)
 }
diff --git a/common/geodata/decode_test.go b/common/geodata/decode_test.go
index d4b84d3..0c9e164 100644
--- a/common/geodata/decode_test.go
+++ b/common/geodata/decode_test.go
@@ -29,13 +29,13 @@ func init() {
 	geositePath := common.GetAssetLocation("geosite.dat")
 
 	if _, err := os.Stat(geoipPath); err != nil && errors.Is(err, fs.ErrNotExist) {
-		common.Must(os.MkdirAll(tempPath, 0755))
+		common.Must(os.MkdirAll(tempPath, 0o755))
 		geoipBytes, err := common.FetchHTTPContent(geoipURL)
 		common.Must(err)
 		common.Must(common.WriteFile(geoipPath, geoipBytes))
 	}
 	if _, err := os.Stat(geositePath); err != nil && errors.Is(err, fs.ErrNotExist) {
-		common.Must(os.MkdirAll(tempPath, 0755))
+		common.Must(os.MkdirAll(tempPath, 0o755))
 		geositeBytes, err := common.FetchHTTPContent(geositeURL)
 		common.Must(err)
 		common.Must(common.WriteFile(geositePath, geositeBytes))
diff --git a/log/log.go b/log/log.go
index 929bd57..bbd380a 100644
--- a/log/log.go
+++ b/log/log.go
@@ -5,8 +5,8 @@ import (
 	"os"
 )
 
-//LogLevel how much log to dump
-//0: ALL; 1: INFO; 2: WARN; 3: ERROR; 4: FATAL; 5: OFF
+// LogLevel how much log to dump
+// 0: ALL; 1: INFO; 2: WARN; 3: ERROR; 4: FATAL; 5: OFF
 type LogLevel int
 
 const (
diff --git a/log/simplelog/simplelog.go b/log/simplelog/simplelog.go
index aea5175..467a9b1 100644
--- a/log/simplelog/simplelog.go
+++ b/log/simplelog/simplelog.go
@@ -95,5 +95,5 @@ func (l *SimpleLogger) Tracef(format string, v ...interface{}) {
 }
 
 func (l *SimpleLogger) SetOutput(io.Writer) {
-	//do nothing
+	// do nothing
 }
diff --git a/proxy/proxy.go b/proxy/proxy.go
index 631bcda..c5a286a 100644
--- a/proxy/proxy.go
+++ b/proxy/proxy.go
@@ -190,7 +190,7 @@ func NewProxyFromConfigData(data []byte, isJSON bool) (*Proxy, error) {
 	}
 	log.SetLogLevel(log.LogLevel(cfg.LogLevel))
 	if cfg.LogFile != "" {
-		file, err := os.OpenFile(cfg.LogFile, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0644)
+		file, err := os.OpenFile(cfg.LogFile, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0o644)
 		if err != nil {
 			return nil, common.NewError("failed to open log file").Base(err)
 		}
diff --git a/proxy/server/server.go b/proxy/server/server.go
index baa5366..20f4ba3 100644
--- a/proxy/server/server.go
+++ b/proxy/server/server.go
@@ -67,5 +67,4 @@ func init() {
 		}
 		return proxy.NewProxy(ctx, cancel, serverList, clientList), nil
 	})
-
 }
diff --git a/statistic/mysql/mysql.go b/statistic/mysql/mysql.go
index 7fc1af1..9431005 100644
--- a/statistic/mysql/mysql.go
+++ b/statistic/mysql/mysql.go
@@ -7,12 +7,11 @@ import (
 	"strings"
 	"time"
 
-	"github.com/p4gefau1t/trojan-go/config"
-
 	// MySQL Driver
 	_ "github.com/go-sql-driver/mysql"
 
 	"github.com/p4gefau1t/trojan-go/common"
+	"github.com/p4gefau1t/trojan-go/config"
 	"github.com/p4gefau1t/trojan-go/log"
 	"github.com/p4gefau1t/trojan-go/statistic"
 	"github.com/p4gefau1t/trojan-go/statistic/memory"
@@ -30,7 +29,7 @@ type Authenticator struct {
 func (a *Authenticator) updater() {
 	for {
 		for _, user := range a.ListUsers() {
-			//swap upload and download for users
+			// swap upload and download for users
 			hash := user.Hash()
 			sent, recv := user.ResetTraffic()
 
@@ -47,7 +46,7 @@ func (a *Authenticator) updater() {
 		}
 		log.Info("buffered data has been written into the database")
 
-		//update memory
+		// update memory
 		rows, err := a.db.Query("SELECT password,quota,download,upload FROM users")
 		if err != nil {
 			log.Error(common.NewError("failed to pull data from the database").Base(err))
diff --git a/statistic/statistics.go b/statistic/statistics.go
index d796523..411d410 100644
--- a/statistic/statistics.go
+++ b/statistic/statistics.go
@@ -15,11 +15,11 @@ type TrafficMeter interface {
 	Hash() string
 	AddTraffic(sent, recv int)
 	GetTraffic() (sent, recv uint64)
+	SetTraffic(sent, recv uint64)
 	ResetTraffic() (sent, recv uint64)
 	GetSpeed() (sent, recv uint64)
-	SetSpeedLimit(sent, recv int)
 	GetSpeedLimit() (sent, recv int)
-	SetTraffic(sent, recv uint64)
+	SetSpeedLimit(sent, recv int)
 }
 
 type IPRecorder interface {
@@ -45,9 +45,11 @@ type Authenticator interface {
 
 type Creator func(ctx context.Context) (Authenticator, error)
 
-var authCreators = map[string]Creator{}
-var createdAuth = map[context.Context]Authenticator{}
-var createdAuthLock = sync.Mutex{}
+var (
+	createdAuthLock sync.Mutex
+	authCreators    = make(map[string]Creator)
+	createdAuth     = make(map[context.Context]Authenticator)
+)
 
 func RegisterAuthenticatorCreator(name string, creator Creator) {
 	authCreators[name] = creator
diff --git a/test/scenario/proxy_test.go b/test/scenario/proxy_test.go
index dd4d28f..41eb35f 100644
--- a/test/scenario/proxy_test.go
+++ b/test/scenario/proxy_test.go
@@ -81,8 +81,8 @@ NYpAJoagHIeNLGo4aJFwiVsZ
 `
 
 func init() {
-	ioutil.WriteFile("server.crt", []byte(cert), 0777)
-	ioutil.WriteFile("server.key", []byte(key), 0777)
+	ioutil.WriteFile("server.crt", []byte(cert), 0o777)
+	ioutil.WriteFile("server.key", []byte(key), 0o777)
 }
 
 func CheckClientServer(clientData, serverData string, socksPort int) (ok bool) {
@@ -457,7 +457,7 @@ api:
 	time.Sleep(time.Second * 3)
 	client.Close()
 	time.Sleep(time.Second * 3)
-	//http.ListenAndServe("localhost:6060", nil)
+	// http.ListenAndServe("localhost:6060", nil)
 }
 
 func SingleThreadBenchmark(clientData, serverData string, socksPort int) {
diff --git a/test/util/target.go b/test/util/target.go
index a6da498..21d849e 100644
--- a/test/util/target.go
+++ b/test/util/target.go
@@ -16,8 +16,10 @@ import (
 	"github.com/p4gefau1t/trojan-go/log"
 )
 
-var HTTPAddr string
-var HTTPPort string
+var (
+	HTTPAddr string
+	HTTPPort string
+)
 
 func runHelloHTTPServer() {
 	httpHello := func(w http.ResponseWriter, req *http.Request) {
@@ -51,8 +53,10 @@ func runHelloHTTPServer() {
 	wg.Done()
 }
 
-var EchoAddr string
-var EchoPort int
+var (
+	EchoAddr string
+	EchoPort int
+)
 
 func runTCPEchoServer() {
 	listener, err := net.Listen("tcp", EchoAddr)
@@ -108,8 +112,10 @@ func GeneratePayload(length int) []byte {
 	return buf
 }
 
-var BlackHoleAddr string
-var BlackHolePort int
+var (
+	BlackHoleAddr string
+	BlackHolePort int
+)
 
 func runTCPBlackHoleServer() {
 	listener, err := net.Listen("tcp", BlackHoleAddr)
diff --git a/tunnel/freedom/conn.go b/tunnel/freedom/conn.go
index 8ef5456..75d8783 100644
--- a/tunnel/freedom/conn.go
+++ b/tunnel/freedom/conn.go
@@ -65,7 +65,7 @@ type SocksPacketConn struct {
 
 func (c *SocksPacketConn) WriteWithMetadata(payload []byte, metadata *tunnel.Metadata) (int, error) {
 	buf := bytes.NewBuffer(make([]byte, 0, MaxPacketSize))
-	buf.Write([]byte{0, 0, 0}) //RSV, FRAG
+	buf.Write([]byte{0, 0, 0}) // RSV, FRAG
 	common.Must(metadata.Address.WriteTo(buf))
 	buf.Write(payload)
 	_, err := c.PacketConn.WriteTo(buf.Bytes(), c.socksAddr)
diff --git a/tunnel/http/server.go b/tunnel/http/server.go
index ad349b8..b274270 100644
--- a/tunnel/http/server.go
+++ b/tunnel/http/server.go
@@ -26,7 +26,7 @@ func (c *ConnectConn) Metadata() *tunnel.Metadata {
 
 type OtherConn struct {
 	net.Conn
-	metadata   *tunnel.Metadata //fixed
+	metadata   *tunnel.Metadata // fixed
 	reqReader  *io.PipeReader
 	respWriter *io.PipeWriter
 	ctx        context.Context
@@ -156,7 +156,7 @@ func (s *Server) acceptLoop() {
 					req.Body.Close()
 					resp.Body.Close()
 
-					req, err = http.ReadRequest(reqBufReader) //read the next http request from local
+					req, err = http.ReadRequest(reqBufReader) // read the next http request from local
 					if err != nil {
 						log.Error(common.NewError("http failed to the read request from local").Base(err))
 						return
diff --git a/tunnel/metadata.go b/tunnel/metadata.go
index afdbde3..07dbc67 100644
--- a/tunnel/metadata.go
+++ b/tunnel/metadata.go
@@ -39,7 +39,7 @@ func (r *Metadata) WriteTo(w io.Writer) error {
 	if err := r.Address.WriteTo(buf); err != nil {
 		return err
 	}
-	//use tcp by default
+	// use tcp by default
 	r.Address.NetworkType = "tcp"
 	_, err := w.Write(buf.Bytes())
 	return err
@@ -171,7 +171,7 @@ func (a *Address) ReadFrom(r io.Reader) error {
 		if err != nil {
 			return common.NewError("failed to read domain name")
 		}
-		//the fucking browser uses IP as a domain name sometimes
+		// the fucking browser uses IP as a domain name sometimes
 		host := buf[0:length]
 		if ip := net.ParseIP(string(host)); ip != nil {
 			a.IP = ip
diff --git a/tunnel/mux/client.go b/tunnel/mux/client.go
index d863f26..720293c 100644
--- a/tunnel/mux/client.go
+++ b/tunnel/mux/client.go
@@ -28,7 +28,7 @@ type smuxClientInfo struct {
 	underlayConn   tunnel.Conn
 }
 
-//Client is a smux client
+// Client is a smux client
 type Client struct {
 	clientPoolLock sync.Mutex
 	clientPool     map[muxID]*smuxClientInfo
@@ -114,7 +114,7 @@ func (c *Client) newMuxClient() (*smuxClientInfo, error) {
 	conn = newStickyConn(conn)
 
 	smuxConfig := smux.DefaultConfig()
-	//smuxConfig.KeepAliveDisabled = true
+	// smuxConfig.KeepAliveDisabled = true
 	client, err := smux.Client(conn, smuxConfig)
 	info := &smuxClientInfo{
 		client:         client,
diff --git a/tunnel/mux/config.go b/tunnel/mux/config.go
index 35570f3..02fdf46 100644
--- a/tunnel/mux/config.go
+++ b/tunnel/mux/config.go
@@ -22,5 +22,4 @@ func init() {
 			},
 		}
 	})
-
 }
diff --git a/tunnel/mux/conn.go b/tunnel/mux/conn.go
index cf852d3..5b2d958 100644
--- a/tunnel/mux/conn.go
+++ b/tunnel/mux/conn.go
@@ -48,7 +48,7 @@ func (c *stickyConn) Close() error {
 
 func (c *stickyConn) Write(p []byte) (int, error) {
 	if len(p) == 8 {
-		if p[0] == 1 || p[0] == 2 { //smux 8 bytes header
+		if p[0] == 1 || p[0] == 2 { // smux 8 bytes header
 			switch p[1] {
 			// THE CONTENT OF THE BUFFER MIGHT CHANGE
 			// NEVER STORE THE POINTER TO HEADER, COPY THE HEADER INSTEAD
diff --git a/tunnel/mux/server.go b/tunnel/mux/server.go
index 40d22a0..7724f94 100644
--- a/tunnel/mux/server.go
+++ b/tunnel/mux/server.go
@@ -32,7 +32,7 @@ func (s *Server) acceptConnWorker() {
 		}
 		go func(conn tunnel.Conn) {
 			smuxConfig := smux.DefaultConfig()
-			//smuxConfig.KeepAliveDisabled = true
+			// smuxConfig.KeepAliveDisabled = true
 			smuxSession, err := smux.Server(conn, smuxConfig)
 			if err != nil {
 				log.Error(err)
diff --git a/tunnel/router/client.go b/tunnel/router/client.go
index 33ed00a..30874a7 100644
--- a/tunnel/router/client.go
+++ b/tunnel/router/client.go
@@ -52,7 +52,7 @@ func matchDomain(list []*v2router.Domain, target string) bool {
 				}
 			}
 		case v2router.Domain_Plain:
-			//keyword
+			// keyword
 			if strings.Contains(target, d.GetValue()) {
 				log.Tracef("domain %s hit keyword rule: %s", target, d.GetValue())
 				return true
@@ -85,11 +85,11 @@ func matchIP(list []*v2router.CIDR, target net.IP) bool {
 		n := int(c.GetPrefix())
 		mask := net.CIDRMask(n, 8*len)
 		cidrIP := net.IP(c.GetIp())
-		if cidrIP.To4() != nil { //IPv4 CIDR
+		if cidrIP.To4() != nil { // IPv4 CIDR
 			if isIPv6 {
 				continue
 			}
-		} else { //IPv6 CIDR
+		} else { // IPv6 CIDR
 			if !isIPv6 {
 				continue
 			}
diff --git a/tunnel/router/router_test.go b/tunnel/router/router_test.go
index 00e16f6..49e4cac 100644
--- a/tunnel/router/router_test.go
+++ b/tunnel/router/router_test.go
@@ -28,8 +28,7 @@ func (m MockClient) Close() error {
 	return nil
 }
 
-type MockPacketConn struct {
-}
+type MockPacketConn struct{}
 
 func (m MockPacketConn) ReadFrom(p []byte) (n int, addr net.Addr, err error) {
 	panic("implement me")
diff --git a/tunnel/socks/server.go b/tunnel/socks/server.go
index b6350ae..ddd2338 100644
--- a/tunnel/socks/server.go
+++ b/tunnel/socks/server.go
@@ -145,7 +145,7 @@ func (s *Server) packetDispatchLoop() {
 					select {
 					case info := <-conn.output:
 						buf := bytes.NewBuffer(make([]byte, 0, MaxPacketSize))
-						buf.Write([]byte{0, 0, 0}) //RSV, FRAG
+						buf.Write([]byte{0, 0, 0}) // RSV, FRAG
 						common.Must(info.metadata.Address.WriteTo(buf))
 						buf.Write(info.payload)
 						_, err := s.listenPacketConn.WriteTo(buf.Bytes(), conn.src)
diff --git a/tunnel/socks/socks_test.go b/tunnel/socks/socks_test.go
index fd5a763..7697cd7 100644
--- a/tunnel/socks/socks_test.go
+++ b/tunnel/socks/socks_test.go
@@ -73,7 +73,7 @@ func TestSocks(t *testing.T) {
 
 	payload := util.GeneratePayload(1024)
 	buf := bytes.NewBuffer(make([]byte, 0, 4096))
-	buf.Write([]byte{0, 0, 0}) //RSV, FRAG
+	buf.Write([]byte{0, 0, 0}) // RSV, FRAG
 	common.Must(addr.WriteTo(buf))
 	buf.Write(payload)
 
diff --git a/tunnel/socks/tunnel.go b/tunnel/socks/tunnel.go
index 9486bf2..7ab6b29 100644
--- a/tunnel/socks/tunnel.go
+++ b/tunnel/socks/tunnel.go
@@ -13,9 +13,11 @@ type Tunnel struct{}
 func (*Tunnel) Name() string {
 	return Name
 }
+
 func (*Tunnel) NewClient(context.Context, tunnel.Client) (tunnel.Client, error) {
 	panic("not supported")
 }
+
 func (*Tunnel) NewServer(ctx context.Context, server tunnel.Server) (tunnel.Server, error) {
 	return NewServer(ctx, server)
 }
diff --git a/tunnel/tls/server.go b/tunnel/tls/server.go
index ccfd70b..c3ccd14 100644
--- a/tunnel/tls/server.go
+++ b/tunnel/tls/server.go
@@ -77,7 +77,6 @@ func (s *Server) acceptLoop() {
 			return
 		}
 		go func(conn net.Conn) {
-
 			tlsConfig := &tls.Config{
 				CipherSuites:             s.cipherSuite,
 				PreferServerCipherSuites: s.PreferServerCipher,
@@ -315,7 +314,7 @@ func NewServer(ctx context.Context, underlay tunnel.Server) (*Server, error) {
 	var keyLogger io.WriteCloser
 	if cfg.TLS.KeyLogPath != "" {
 		log.Warn("tls key logging activated. USE OF KEY LOGGING COMPROMISES SECURITY. IT SHOULD ONLY BE USED FOR DEBUGGING.")
-		file, err := os.OpenFile(cfg.TLS.KeyLogPath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0600)
+		file, err := os.OpenFile(cfg.TLS.KeyLogPath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0o600)
 		if err != nil {
 			return nil, common.NewError("failed to open key log file").Base(err)
 		}
diff --git a/tunnel/tls/tls_test.go b/tunnel/tls/tls_test.go
index 4a23555..31e683d 100644
--- a/tunnel/tls/tls_test.go
+++ b/tunnel/tls/tls_test.go
@@ -69,8 +69,8 @@ WS94/5WE/lwHJi8ZPSjH1AURCzXhUi4fGvBrNBtry95e+jcEvP5c0g==
 `
 
 func TestDefaultTLS(t *testing.T) {
-	ioutil.WriteFile("server.crt", []byte(cert), 0777)
-	ioutil.WriteFile("server.key", []byte(key), 0777)
+	ioutil.WriteFile("server.crt", []byte(cert), 0o777)
+	ioutil.WriteFile("server.key", []byte(key), 0o777)
 	serverCfg := &Config{
 		TLS: TLSConfig{
 			VerifyHostName: true,
@@ -131,8 +131,8 @@ func TestDefaultTLS(t *testing.T) {
 }
 
 func TestUTLS(t *testing.T) {
-	ioutil.WriteFile("server.crt", []byte(cert), 0777)
-	ioutil.WriteFile("server.key", []byte(key), 0777)
+	ioutil.WriteFile("server.crt", []byte(cert), 0o777)
+	ioutil.WriteFile("server.key", []byte(key), 0o777)
 	fingerprints := []string{
 		"chrome",
 		"firefox",
diff --git a/tunnel/trojan/packet.go b/tunnel/trojan/packet.go
index 4946057..9bdbb1b 100644
--- a/tunnel/trojan/packet.go
+++ b/tunnel/trojan/packet.go
@@ -72,7 +72,7 @@ func (c *PacketConn) ReadWithMetadata(payload []byte) (int, *tunnel.Metadata, er
 	}
 
 	if len(payload) < length || length > MaxPacketSize {
-		io.CopyN(ioutil.Discard, c.Conn, int64(length)) //drain the rest of the packet
+		io.CopyN(ioutil.Discard, c.Conn, int64(length)) // drain the rest of the packet
 		return 0, nil, common.NewError("incoming packet size is too large")
 	}
 	_, err = io.ReadFull(c.Conn, payload[:length])
diff --git a/tunnel/trojan/trojan_test.go b/tunnel/trojan/trojan_test.go
index 2295337..cda1416 100644
--- a/tunnel/trojan/trojan_test.go
+++ b/tunnel/trojan/trojan_test.go
@@ -86,7 +86,7 @@ func TestTrojan(t *testing.T) {
 		t.Fail()
 	}
 
-	//redirecting
+	// redirecting
 	conn, err := net.Dial("tcp", fmt.Sprintf("127.0.0.1:%d", port))
 	common.Must(err)
 	sendBuf := util.GeneratePayload(1024)
diff --git a/tunnel/websocket/server.go b/tunnel/websocket/server.go
index 3d1925e..7ca0a86 100644
--- a/tunnel/websocket/server.go
+++ b/tunnel/websocket/server.go
@@ -66,7 +66,6 @@ func (s *Server) AcceptConn(tunnel.Tunnel) (tunnel.Conn, error) {
 	defer rewindConn.StopBuffering()
 	rw := bufio.NewReadWriter(bufio.NewReader(rewindConn), bufio.NewWriter(rewindConn))
 	req, err := http.ReadRequest(rw.Reader)
-
 	if err != nil {
 		log.Debug("invalid http request")
 		rewindConn.Rewind()
diff --git a/url/share_link_test.go b/url/share_link_test.go
index 4b30079..cf0b052 100644
--- a/url/share_link_test.go
+++ b/url/share_link_test.go
@@ -122,7 +122,6 @@ func TestNewShareInfoFromURL_BadQuery(t *testing.T) {
 		_, e := NewShareInfoFromURL(testCase)
 		assert.Error(t, e, "parse bad query should error")
 	}
-
 }
 
 func TestNewShareInfoFromURL_SNI_Empty(t *testing.T) {