diff --git a/app/commander/outbound.go b/app/commander/outbound.go
index 907497059..0a849ddd1 100644
--- a/app/commander/outbound.go
+++ b/app/commander/outbound.go
@@ -22,9 +22,9 @@ func (l *OutboundListener) add(conn net.Conn) {
 	select {
 	case l.buffer <- conn:
 	case <-l.done.Wait():
-		conn.Close() // nolint: errcheck
+		conn.Close()
 	default:
-		conn.Close() // nolint: errcheck
+		conn.Close()
 	}
 }
 
@@ -45,7 +45,7 @@ L:
 	for {
 		select {
 		case c := <-l.buffer:
-			c.Close() // nolint: errcheck
+			c.Close()
 		default:
 			break L
 		}
diff --git a/app/dns/dnscommon_test.go b/app/dns/dnscommon_test.go
index 7d81190af..24cc69270 100644
--- a/app/dns/dnscommon_test.go
+++ b/app/dns/dnscommon_test.go
@@ -89,7 +89,6 @@ func Test_parseResponse(t *testing.T) {
 }
 
 func Test_buildReqMsgs(t *testing.T) {
-
 	stubID := func() uint16 {
 		return uint16(rand.Uint32())
 	}
diff --git a/app/dns/dohdns.go b/app/dns/dohdns.go
index 257023ff8..1bb61dee5 100644
--- a/app/dns/dohdns.go
+++ b/app/dns/dohdns.go
@@ -43,7 +43,6 @@ type DoHNameServer struct {
 
 // NewDoHNameServer creates DOH client object for remote resolving
 func NewDoHNameServer(url *url.URL, dispatcher routing.Dispatcher, clientIP net.IP) (*DoHNameServer, error) {
-
 	newError("DNS: created Remote DOH client for ", url.String()).AtInfo().WriteToLog()
 	s := baseDOHNameServer(url, "DOH", clientIP)
 
@@ -112,7 +111,6 @@ func NewDoHLocalNameServer(url *url.URL, clientIP net.IP) *DoHNameServer {
 }
 
 func baseDOHNameServer(url *url.URL, prefix string, clientIP net.IP) *DoHNameServer {
-
 	s := &DoHNameServer{
 		ips:      make(map[string]record),
 		clientIP: clientIP,
diff --git a/app/dns/hosts.go b/app/dns/hosts.go
index f47a32fef..21dc30ba8 100644
--- a/app/dns/hosts.go
+++ b/app/dns/hosts.go
@@ -66,7 +66,8 @@ func NewStaticHosts(hosts []*Config_HostMapping, legacy map[string]*net.IPOrDoma
 		}
 		id := g.Add(matcher)
 		ips := make([]net.Address, 0, len(mapping.Ip)+1)
-		if len(mapping.Ip) > 0 {
+		switch {
+		case len(mapping.Ip) > 0:
 			for _, ip := range mapping.Ip {
 				addr := net.IPAddress(ip)
 				if addr == nil {
@@ -74,9 +75,11 @@ func NewStaticHosts(hosts []*Config_HostMapping, legacy map[string]*net.IPOrDoma
 				}
 				ips = append(ips, addr)
 			}
-		} else if len(mapping.ProxiedDomain) > 0 {
+
+		case len(mapping.ProxiedDomain) > 0:
 			ips = append(ips, net.DomainAddress(mapping.ProxiedDomain))
-		} else {
+
+		default:
 			return nil, newError("neither IP address nor proxied domain specified for domain: ", mapping.Domain).AtWarning()
 		}
 
diff --git a/app/dns/nameserver.go b/app/dns/nameserver.go
index c002e2e99..c55f901cf 100644
--- a/app/dns/nameserver.go
+++ b/app/dns/nameserver.go
@@ -24,11 +24,11 @@ type Client interface {
 	QueryIP(ctx context.Context, domain string, option IPOption) ([]net.IP, error)
 }
 
-type localNameServer struct {
+type LocalNameServer struct {
 	client *localdns.Client
 }
 
-func (s *localNameServer) QueryIP(ctx context.Context, domain string, option IPOption) ([]net.IP, error) {
+func (s *LocalNameServer) QueryIP(ctx context.Context, domain string, option IPOption) ([]net.IP, error) {
 	if option.IPv4Enable && option.IPv6Enable {
 		return s.client.LookupIP(domain)
 	}
@@ -44,13 +44,13 @@ func (s *localNameServer) QueryIP(ctx context.Context, domain string, option IPO
 	return nil, newError("neither IPv4 nor IPv6 is enabled")
 }
 
-func (s *localNameServer) Name() string {
+func (s *LocalNameServer) Name() string {
 	return "localhost"
 }
 
-func NewLocalNameServer() *localNameServer {
+func NewLocalNameServer() *LocalNameServer {
 	newError("DNS: created localhost client").AtInfo().WriteToLog()
-	return &localNameServer{
+	return &LocalNameServer{
 		client: localdns.New(),
 	}
 }
diff --git a/app/dns/server.go b/app/dns/server.go
index 0693fa1e0..ecf4d2153 100644
--- a/app/dns/server.go
+++ b/app/dns/server.go
@@ -97,7 +97,9 @@ func New(ctx context.Context, config *Config) (*Server, error) {
 	addNameServer := func(ns *NameServer) int {
 		endpoint := ns.Address
 		address := endpoint.Address.AsAddress()
-		if address.Family().IsDomain() && address.Domain() == "localhost" {
+
+		switch {
+		case address.Family().IsDomain() && address.Domain() == "localhost":
 			server.clients = append(server.clients, NewLocalNameServer())
 			// Priotize local domains with specific TLDs or without any dot to local DNS
 			// References:
@@ -115,7 +117,8 @@ func New(ctx context.Context, config *Config) (*Server, error) {
 				{Type: DomainMatchingType_Subdomain, Domain: "test"},
 			}
 			ns.PrioritizedDomain = append(ns.PrioritizedDomain, localTLDsAndDotlessDomains...)
-		} else if address.Family().IsDomain() && strings.HasPrefix(address.Domain(), "https+local://") {
+
+		case address.Family().IsDomain() && strings.HasPrefix(address.Domain(), "https+local://"):
 			// URI schemed string treated as domain
 			// DOH Local mode
 			u, err := url.Parse(address.Domain())
@@ -123,7 +126,8 @@ func New(ctx context.Context, config *Config) (*Server, error) {
 				log.Fatalln(newError("DNS config error").Base(err))
 			}
 			server.clients = append(server.clients, NewDoHLocalNameServer(u, server.clientIP))
-		} else if address.Family().IsDomain() && strings.HasPrefix(address.Domain(), "https://") {
+
+		case address.Family().IsDomain() && strings.HasPrefix(address.Domain(), "https://"):
 			// DOH Remote mode
 			u, err := url.Parse(address.Domain())
 			if err != nil {
@@ -140,7 +144,8 @@ func New(ctx context.Context, config *Config) (*Server, error) {
 				}
 				server.clients[idx] = c
 			}))
-		} else {
+
+		default:
 			// UDP classic DNS mode
 			dest := endpoint.AsDestination()
 			if dest.Network == net.Network_Unknown {
diff --git a/app/dns/server_test.go b/app/dns/server_test.go
index de3f8caf7..f988ad4a0 100644
--- a/app/dns/server_test.go
+++ b/app/dns/server_test.go
@@ -42,7 +42,8 @@ func (*staticHandler) ServeDNS(w dns.ResponseWriter, r *dns.Msg) {
 	}
 
 	for _, q := range r.Question {
-		if q.Name == "google.com." && q.Qtype == dns.TypeA {
+		switch {
+		case q.Name == "google.com." && q.Qtype == dns.TypeA:
 			if clientIP == nil {
 				rr, _ := dns.NewRR("google.com. IN A 8.8.8.8")
 				ans.Answer = append(ans.Answer, rr)
@@ -50,44 +51,57 @@ func (*staticHandler) ServeDNS(w dns.ResponseWriter, r *dns.Msg) {
 				rr, _ := dns.NewRR("google.com. IN A 8.8.4.4")
 				ans.Answer = append(ans.Answer, rr)
 			}
-		} else if q.Name == "api.google.com." && q.Qtype == dns.TypeA {
+
+		case q.Name == "api.google.com." && q.Qtype == dns.TypeA:
 			rr, _ := dns.NewRR("api.google.com. IN A 8.8.7.7")
 			ans.Answer = append(ans.Answer, rr)
-		} else if q.Name == "v2.api.google.com." && q.Qtype == dns.TypeA {
+
+		case q.Name == "v2.api.google.com." && q.Qtype == dns.TypeA:
 			rr, _ := dns.NewRR("v2.api.google.com. IN A 8.8.7.8")
 			ans.Answer = append(ans.Answer, rr)
-		} else if q.Name == "facebook.com." && q.Qtype == dns.TypeA {
+
+		case q.Name == "facebook.com." && q.Qtype == dns.TypeA:
 			rr, _ := dns.NewRR("facebook.com. IN A 9.9.9.9")
 			ans.Answer = append(ans.Answer, rr)
-		} else if q.Name == "ipv6.google.com." && q.Qtype == dns.TypeA {
+
+		case q.Name == "ipv6.google.com." && q.Qtype == dns.TypeA:
 			rr, err := dns.NewRR("ipv6.google.com. IN A 8.8.8.7")
 			common.Must(err)
 			ans.Answer = append(ans.Answer, rr)
-		} else if q.Name == "ipv6.google.com." && q.Qtype == dns.TypeAAAA {
+
+		case q.Name == "ipv6.google.com." && q.Qtype == dns.TypeAAAA:
 			rr, err := dns.NewRR("ipv6.google.com. IN AAAA 2001:4860:4860::8888")
 			common.Must(err)
 			ans.Answer = append(ans.Answer, rr)
-		} else if q.Name == "notexist.google.com." && q.Qtype == dns.TypeAAAA {
+
+		case q.Name == "notexist.google.com." && q.Qtype == dns.TypeAAAA:
 			ans.MsgHdr.Rcode = dns.RcodeNameError
-		} else if q.Name == "hostname." && q.Qtype == dns.TypeA {
+
+		case q.Name == "hostname." && q.Qtype == dns.TypeA:
 			rr, _ := dns.NewRR("hostname. IN A 127.0.0.1")
 			ans.Answer = append(ans.Answer, rr)
-		} else if q.Name == "hostname.local." && q.Qtype == dns.TypeA {
+
+		case q.Name == "hostname.local." && q.Qtype == dns.TypeA:
 			rr, _ := dns.NewRR("hostname.local. IN A 127.0.0.1")
 			ans.Answer = append(ans.Answer, rr)
-		} else if q.Name == "hostname.localdomain." && q.Qtype == dns.TypeA {
+
+		case q.Name == "hostname.localdomain." && q.Qtype == dns.TypeA:
 			rr, _ := dns.NewRR("hostname.localdomain. IN A 127.0.0.1")
 			ans.Answer = append(ans.Answer, rr)
-		} else if q.Name == "localhost." && q.Qtype == dns.TypeA {
+
+		case q.Name == "localhost." && q.Qtype == dns.TypeA:
 			rr, _ := dns.NewRR("localhost. IN A 127.0.0.2")
 			ans.Answer = append(ans.Answer, rr)
-		} else if q.Name == "localhost-a." && q.Qtype == dns.TypeA {
+
+		case q.Name == "localhost-a." && q.Qtype == dns.TypeA:
 			rr, _ := dns.NewRR("localhost-a. IN A 127.0.0.3")
 			ans.Answer = append(ans.Answer, rr)
-		} else if q.Name == "localhost-b." && q.Qtype == dns.TypeA {
+
+		case q.Name == "localhost-b." && q.Qtype == dns.TypeA:
 			rr, _ := dns.NewRR("localhost-b. IN A 127.0.0.4")
 			ans.Answer = append(ans.Answer, rr)
-		} else if q.Name == "Mijia\\ Cloud." && q.Qtype == dns.TypeA {
+
+		case q.Name == "Mijia\\ Cloud." && q.Qtype == dns.TypeA:
 			rr, _ := dns.NewRR("Mijia\\ Cloud. IN A 127.0.0.1")
 			ans.Answer = append(ans.Answer, rr)
 		}
diff --git a/app/dns/udpns.go b/app/dns/udpns.go
index a362c1dff..267f15e96 100644
--- a/app/dns/udpns.go
+++ b/app/dns/udpns.go
@@ -36,7 +36,6 @@ type ClassicNameServer struct {
 }
 
 func NewClassicNameServer(address net.Destination, dispatcher routing.Dispatcher, clientIP net.IP) *ClassicNameServer {
-
 	// default to 53 if unspecific
 	if address.Port == 0 {
 		address.Port = net.Port(53)
@@ -105,7 +104,6 @@ func (s *ClassicNameServer) Cleanup() error {
 }
 
 func (s *ClassicNameServer) HandleResponse(ctx context.Context, packet *udp_proto.Packet) {
-
 	ipRec, err := parseResponse(packet.Payload.Bytes())
 	if err != nil {
 		newError(s.name, " fail to parse responded DNS udp").AtError().WriteToLog()
@@ -240,7 +238,6 @@ func (s *ClassicNameServer) findIPsForDomain(domain string, option IPOption) ([]
 }
 
 func (s *ClassicNameServer) QueryIP(ctx context.Context, domain string, option IPOption) ([]net.IP, error) {
-
 	fqdn := Fqdn(domain)
 
 	ips, err := s.findIPsForDomain(fqdn, option)
diff --git a/app/log/log.go b/app/log/log.go
index bf95a4ce6..ae78be3b3 100644
--- a/app/log/log.go
+++ b/app/log/log.go
@@ -127,10 +127,10 @@ func (g *Instance) Close() error {
 
 	g.active = false
 
-	common.Close(g.accessLogger) // nolint: errcheck
+	common.Close(g.accessLogger)
 	g.accessLogger = nil
 
-	common.Close(g.errorLogger) // nolint: errcheck
+	common.Close(g.errorLogger)
 	g.errorLogger = nil
 
 	return nil
diff --git a/app/proxyman/inbound/worker.go b/app/proxyman/inbound/worker.go
index b10a5867b..dc0677612 100644
--- a/app/proxyman/inbound/worker.go
+++ b/app/proxyman/inbound/worker.go
@@ -280,7 +280,7 @@ func (w *udpWorker) callback(b *buf.Buffer, source net.Destination, originalDest
 	conn, existing := w.getConnection(id)
 
 	// payload will be discarded in pipe is full.
-	conn.writer.WriteMultiBuffer(buf.MultiBuffer{b}) // nolint: errcheck
+	conn.writer.WriteMultiBuffer(buf.MultiBuffer{b})
 
 	if !existing {
 		common.Must(w.checker.Start())
@@ -303,7 +303,7 @@ func (w *udpWorker) callback(b *buf.Buffer, source net.Destination, originalDest
 			if err := w.proxy.Process(ctx, net.Network_UDP, conn, w.dispatcher); err != nil {
 				newError("connection ends").Base(err).WriteToLog(session.ExportIDToError(ctx))
 			}
-			conn.Close() // nolint: errcheck
+			conn.Close()
 			w.removeConn(id)
 		}()
 	}
@@ -332,9 +332,9 @@ func (w *udpWorker) clean() error {
 	}
 
 	for addr, conn := range w.activeConn {
-		if nowSec-atomic.LoadInt64(&conn.lastActivityTime) > 8 { //TODO Timeout too small
+		if nowSec-atomic.LoadInt64(&conn.lastActivityTime) > 8 { // TODO Timeout too small
 			delete(w.activeConn, addr)
-			conn.Close() // nolint: errcheck
+			conn.Close()
 		}
 	}
 
diff --git a/app/router/command/command.go b/app/router/command/command.go
index f1720f871..fc467fa76 100644
--- a/app/router/command/command.go
+++ b/app/router/command/command.go
@@ -39,7 +39,7 @@ func (s *routingServer) TestRoute(ctx context.Context, request *TestRouteRequest
 		return nil, err
 	}
 	if request.PublishResult && s.routingStats != nil {
-		ctx, _ := context.WithTimeout(context.Background(), 4*time.Second) // nolint: govet
+		ctx, _ := context.WithTimeout(context.Background(), 4*time.Second)
 		s.routingStats.Publish(ctx, route)
 	}
 	return AsProtobufMessage(request.FieldSelectors)(route), nil
@@ -54,7 +54,7 @@ func (s *routingServer) SubscribeRoutingStats(request *SubscribeRoutingStatsRequ
 	if err != nil {
 		return err
 	}
-	defer stats.UnsubscribeClosableChannel(s.routingStats, subscriber) // nolint: errcheck
+	defer stats.UnsubscribeClosableChannel(s.routingStats, subscriber)
 	for {
 		select {
 		case value, ok := <-subscriber:
diff --git a/app/router/router_test.go b/app/router/router_test.go
index 8c1aec0aa..080534d6d 100644
--- a/app/router/router_test.go
+++ b/app/router/router_test.go
@@ -34,12 +34,12 @@ func TestSimpleRouter(t *testing.T) {
 	mockCtl := gomock.NewController(t)
 	defer mockCtl.Finish()
 
-	mockDns := mocks.NewDNSClient(mockCtl)
+	mockDNS := mocks.NewDNSClient(mockCtl)
 	mockOhm := mocks.NewOutboundManager(mockCtl)
 	mockHs := mocks.NewOutboundHandlerSelector(mockCtl)
 
 	r := new(Router)
-	common.Must(r.Init(config, mockDns, &mockOutboundManager{
+	common.Must(r.Init(config, mockDNS, &mockOutboundManager{
 		Manager:         mockOhm,
 		HandlerSelector: mockHs,
 	}))
@@ -73,14 +73,14 @@ func TestSimpleBalancer(t *testing.T) {
 	mockCtl := gomock.NewController(t)
 	defer mockCtl.Finish()
 
-	mockDns := mocks.NewDNSClient(mockCtl)
+	mockDNS := mocks.NewDNSClient(mockCtl)
 	mockOhm := mocks.NewOutboundManager(mockCtl)
 	mockHs := mocks.NewOutboundHandlerSelector(mockCtl)
 
 	mockHs.EXPECT().Select(gomock.Eq([]string{"test-"})).Return([]string{"test"})
 
 	r := new(Router)
-	common.Must(r.Init(config, mockDns, &mockOutboundManager{
+	common.Must(r.Init(config, mockDNS, &mockOutboundManager{
 		Manager:         mockOhm,
 		HandlerSelector: mockHs,
 	}))
@@ -114,11 +114,11 @@ func TestIPOnDemand(t *testing.T) {
 	mockCtl := gomock.NewController(t)
 	defer mockCtl.Finish()
 
-	mockDns := mocks.NewDNSClient(mockCtl)
-	mockDns.EXPECT().LookupIP(gomock.Eq("v2ray.com")).Return([]net.IP{{192, 168, 0, 1}}, nil).AnyTimes()
+	mockDNS := mocks.NewDNSClient(mockCtl)
+	mockDNS.EXPECT().LookupIP(gomock.Eq("v2ray.com")).Return([]net.IP{{192, 168, 0, 1}}, nil).AnyTimes()
 
 	r := new(Router)
-	common.Must(r.Init(config, mockDns, nil))
+	common.Must(r.Init(config, mockDNS, nil))
 
 	ctx := session.ContextWithOutbound(context.Background(), &session.Outbound{Target: net.TCPDestination(net.DomainAddress("v2ray.com"), 80)})
 	route, err := r.PickRoute(routing_session.AsRoutingContext(ctx))
@@ -149,11 +149,11 @@ func TestIPIfNonMatchDomain(t *testing.T) {
 	mockCtl := gomock.NewController(t)
 	defer mockCtl.Finish()
 
-	mockDns := mocks.NewDNSClient(mockCtl)
-	mockDns.EXPECT().LookupIP(gomock.Eq("v2ray.com")).Return([]net.IP{{192, 168, 0, 1}}, nil).AnyTimes()
+	mockDNS := mocks.NewDNSClient(mockCtl)
+	mockDNS.EXPECT().LookupIP(gomock.Eq("v2ray.com")).Return([]net.IP{{192, 168, 0, 1}}, nil).AnyTimes()
 
 	r := new(Router)
-	common.Must(r.Init(config, mockDns, nil))
+	common.Must(r.Init(config, mockDNS, nil))
 
 	ctx := session.ContextWithOutbound(context.Background(), &session.Outbound{Target: net.TCPDestination(net.DomainAddress("v2ray.com"), 80)})
 	route, err := r.PickRoute(routing_session.AsRoutingContext(ctx))
@@ -184,10 +184,10 @@ func TestIPIfNonMatchIP(t *testing.T) {
 	mockCtl := gomock.NewController(t)
 	defer mockCtl.Finish()
 
-	mockDns := mocks.NewDNSClient(mockCtl)
+	mockDNS := mocks.NewDNSClient(mockCtl)
 
 	r := new(Router)
-	common.Must(r.Init(config, mockDns, nil))
+	common.Must(r.Init(config, mockDNS, nil))
 
 	ctx := session.ContextWithOutbound(context.Background(), &session.Outbound{Target: net.TCPDestination(net.LocalHostIP, 80)})
 	route, err := r.PickRoute(routing_session.AsRoutingContext(ctx))
diff --git a/app/stats/channel_test.go b/app/stats/channel_test.go
index b2a1c174c..09184bf57 100644
--- a/app/stats/channel_test.go
+++ b/app/stats/channel_test.go
@@ -388,7 +388,7 @@ func TestStatsChannelConcurrency(t *testing.T) {
 			if ok {
 				errCh <- fmt.Sprint("unexpected receiving: ", v)
 			} else {
-				errCh <- fmt.Sprint("unexpected closing of channel")
+				errCh <- "unexpected closing of channel"
 			}
 		default:
 		}
diff --git a/common/antireplay/antireplay.go b/common/antireplay/antireplay.go
index bdf22f266..9ac4300fd 100644
--- a/common/antireplay/antireplay.go
+++ b/common/antireplay/antireplay.go
@@ -1,14 +1,15 @@
 package antireplay
 
 import (
-	cuckoo "github.com/seiflotfy/cuckoofilter"
 	"sync"
 	"time"
+
+	cuckoo "github.com/seiflotfy/cuckoofilter"
 )
 
-func NewAntiReplayWindow(AntiReplayTime int64) *AntiReplayWindow {
+func NewAntiReplayWindow(antiReplayTime int64) *AntiReplayWindow {
 	arw := &AntiReplayWindow{}
-	arw.AntiReplayTime = AntiReplayTime
+	arw.AntiReplayTime = antiReplayTime
 	return arw
 }
 
diff --git a/common/buf/multi_buffer_test.go b/common/buf/multi_buffer_test.go
index add7a1e19..f0d2776b6 100644
--- a/common/buf/multi_buffer_test.go
+++ b/common/buf/multi_buffer_test.go
@@ -4,12 +4,11 @@ import (
 	"bytes"
 	"crypto/rand"
 	"io"
+	"io/ioutil"
+	"os"
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
-	"io/ioutil"
-	"os"
-
 	"v2ray.com/core/common"
 	. "v2ray.com/core/common/buf"
 )
@@ -110,7 +109,6 @@ func TestMultiBufferReadAllToByte(t *testing.T) {
 		if l := len(b); l != 8*1024 {
 			t.Error("unexpceted length from ReadAllToBytes", l)
 		}
-
 	}
 	{
 		const dat = "data/test_MultiBufferReadAllToByte.dat"
diff --git a/common/buf/reader_test.go b/common/buf/reader_test.go
index 95622eefe..910851094 100644
--- a/common/buf/reader_test.go
+++ b/common/buf/reader_test.go
@@ -88,7 +88,6 @@ func TestReadBuffer(t *testing.T) {
 		}
 		buf.Release()
 	}
-
 }
 
 func TestReadAtMost(t *testing.T) {
diff --git a/common/buf/readv_test.go b/common/buf/readv_test.go
index 190e83d0e..b2a3627d2 100644
--- a/common/buf/readv_test.go
+++ b/common/buf/readv_test.go
@@ -23,11 +23,11 @@ func TestReadvReader(t *testing.T) {
 	}
 	dest, err := tcpServer.Start()
 	common.Must(err)
-	defer tcpServer.Close() // nolint: errcheck
+	defer tcpServer.Close()
 
 	conn, err := net.Dial("tcp", dest.NetAddr())
 	common.Must(err)
-	defer conn.Close() // nolint: errcheck
+	defer conn.Close()
 
 	const size = 8192
 	data := make([]byte, 8192)
diff --git a/common/bytespool/pool.go b/common/bytespool/pool.go
index 24542ffa8..9b0e710e5 100644
--- a/common/bytespool/pool.go
+++ b/common/bytespool/pool.go
@@ -65,7 +65,7 @@ func Free(b []byte) {
 	b = b[0:cap(b)]
 	for i := numPools - 1; i >= 0; i-- {
 		if size >= poolSize[i] {
-			pool[i].Put(b) // nolint: megacheck
+			pool[i].Put(b)
 			return
 		}
 	}
diff --git a/common/dice/dice.go b/common/dice/dice.go
index f5a625592..150a76134 100644
--- a/common/dice/dice.go
+++ b/common/dice/dice.go
@@ -32,15 +32,15 @@ func RollUint64() uint64 {
 	return rand.Uint64()
 }
 
-func NewDeterministicDice(seed int64) *deterministicDice {
-	return &deterministicDice{rand.New(rand.NewSource(seed))}
+func NewDeterministicDice(seed int64) *DeterministicDice {
+	return &DeterministicDice{rand.New(rand.NewSource(seed))}
 }
 
-type deterministicDice struct {
+type DeterministicDice struct {
 	*rand.Rand
 }
 
-func (dd *deterministicDice) Roll(n int) int {
+func (dd *DeterministicDice) Roll(n int) int {
 	if n == 1 {
 		return 0
 	}
diff --git a/common/log/logger.go b/common/log/logger.go
index a6b8316b1..7360c6498 100644
--- a/common/log/logger.go
+++ b/common/log/logger.go
@@ -48,14 +48,14 @@ func (l *generalLogger) run() {
 	if logger == nil {
 		return
 	}
-	defer logger.Close() // nolint: errcheck
+	defer logger.Close()
 
 	for {
 		select {
 		case <-l.done.Wait():
 			return
 		case msg := <-l.buffer:
-			logger.Write(msg.String() + platform.LineSeparator()) // nolint: errcheck
+			logger.Write(msg.String() + platform.LineSeparator())
 			dataWritten = true
 		case <-ticker.C:
 			if !dataWritten {
diff --git a/common/log/logger_test.go b/common/log/logger_test.go
index b41f41dfd..9ce8ca3c6 100644
--- a/common/log/logger_test.go
+++ b/common/log/logger_test.go
@@ -29,7 +29,7 @@ func TestFileLogger(t *testing.T) {
 
 	f, err = os.Open(path)
 	common.Must(err)
-	defer f.Close() // nolint: errcheck
+	defer f.Close()
 
 	b, err := buf.ReadAllToBytes(f)
 	common.Must(err)
diff --git a/common/mux/client.go b/common/mux/client.go
index 9e651bbe5..90ea1cfd5 100644
--- a/common/mux/client.go
+++ b/common/mux/client.go
@@ -214,8 +214,8 @@ func (m *ClientWorker) monitor() {
 		select {
 		case <-m.done.Wait():
 			m.sessionManager.Close()
-			common.Close(m.link.Writer)     // nolint: errcheck
-			common.Interrupt(m.link.Reader) // nolint: errcheck
+			common.Close(m.link.Writer)
+			common.Interrupt(m.link.Reader)
 			return
 		case <-timer.C:
 			size := m.sessionManager.Size()
@@ -247,8 +247,8 @@ func fetchInput(ctx context.Context, s *Session, output buf.Writer) {
 	}
 	s.transferType = transferType
 	writer := NewWriter(s.ID, dest, output, transferType)
-	defer s.Close()      // nolint: errcheck
-	defer writer.Close() // nolint: errcheck
+	defer s.Close()
+	defer writer.Close()
 
 	newError("dispatching request to ", dest).WriteToLog(session.ExportIDToError(ctx))
 	if err := writeFirstPayload(s.input, writer); err != nil {
diff --git a/common/mux/server.go b/common/mux/server.go
index 8985bdd73..c4f9ca920 100644
--- a/common/mux/server.go
+++ b/common/mux/server.go
@@ -232,7 +232,7 @@ func (w *ServerWorker) run(ctx context.Context) {
 	input := w.link.Reader
 	reader := &buf.BufferedReader{Reader: input}
 
-	defer w.sessionManager.Close() // nolint: errcheck
+	defer w.sessionManager.Close()
 
 	for {
 		select {
diff --git a/common/mux/session.go b/common/mux/session.go
index c0759f96f..84764babe 100644
--- a/common/mux/session.go
+++ b/common/mux/session.go
@@ -126,8 +126,8 @@ func (m *SessionManager) Close() error {
 	m.closed = true
 
 	for _, s := range m.sessions {
-		common.Close(s.input)  // nolint: errcheck
-		common.Close(s.output) // nolint: errcheck
+		common.Close(s.input)
+		common.Close(s.output)
 	}
 
 	m.sessions = nil
@@ -145,8 +145,8 @@ type Session struct {
 
 // Close closes all resources associated with this session.
 func (s *Session) Close() error {
-	common.Close(s.output) // nolint: errcheck
-	common.Close(s.input)  // nolint: errcheck
+	common.Close(s.output)
+	common.Close(s.input)
 	s.parent.Remove(s.ID)
 	return nil
 }
diff --git a/common/mux/writer.go b/common/mux/writer.go
index f3b3c1d35..21850ac60 100644
--- a/common/mux/writer.go
+++ b/common/mux/writer.go
@@ -121,6 +121,6 @@ func (w *Writer) Close() error {
 	frame := buf.New()
 	common.Must(meta.WriteTo(frame))
 
-	w.writer.WriteMultiBuffer(buf.MultiBuffer{frame}) // nolint: errcheck
+	w.writer.WriteMultiBuffer(buf.MultiBuffer{frame})
 	return nil
 }
diff --git a/common/net/destination_test.go b/common/net/destination_test.go
index 3cfe915b9..1e160511d 100644
--- a/common/net/destination_test.go
+++ b/common/net/destination_test.go
@@ -90,10 +90,8 @@ func TestDestinationParse(t *testing.T) {
 			if d != testcase.Output {
 				t.Error("for test case: ", testcase.Input, " expected output: ", testcase.Output.String(), " but got ", d.String())
 			}
-		} else {
-			if err == nil {
-				t.Error("for test case: ", testcase.Input, " expected error, but got nil")
-			}
+		} else if err == nil {
+			t.Error("for test case: ", testcase.Input, " expected error, but got nil")
 		}
 	}
 }
diff --git a/common/platform/platform.go b/common/platform/platform.go
index c0bf8c20b..6da185cff 100644
--- a/common/platform/platform.go
+++ b/common/platform/platform.go
@@ -49,7 +49,7 @@ func (f EnvFlag) GetValueAsInt(defaultValue int) int {
 }
 
 func NormalizeEnvName(name string) string {
-	return strings.Replace(strings.ToUpper(strings.TrimSpace(name)), ".", "_", -1)
+	return strings.ReplaceAll(strings.ToUpper(strings.TrimSpace(name)), ".", "_")
 }
 
 func getExecutableDir() string {
diff --git a/common/protocol/tls/cert/cert_test.go b/common/protocol/tls/cert/cert_test.go
index 20ad6239b..830387966 100644
--- a/common/protocol/tls/cert/cert_test.go
+++ b/common/protocol/tls/cert/cert_test.go
@@ -8,6 +8,7 @@ import (
 	"strings"
 	"testing"
 	"time"
+
 	"v2ray.com/core/common"
 	"v2ray.com/core/common/task"
 )
diff --git a/common/retry/retry_test.go b/common/retry/retry_test.go
index ef278423d..9d5ae9042 100644
--- a/common/retry/retry_test.go
+++ b/common/retry/retry_test.go
@@ -10,7 +10,7 @@ import (
 )
 
 var (
-	errorTestOnly = errors.New("This is a fake error.")
+	errorTestOnly = errors.New("this is a fake error")
 )
 
 func TestNoRetry(t *testing.T) {
diff --git a/common/signal/timer.go b/common/signal/timer.go
index 4182d4b2d..afda17754 100644
--- a/common/signal/timer.go
+++ b/common/signal/timer.go
@@ -45,7 +45,7 @@ func (t *ActivityTimer) finish() {
 		t.onTimeout = nil
 	}
 	if t.checkTask != nil {
-		t.checkTask.Close() // nolint: errcheck
+		t.checkTask.Close()
 		t.checkTask = nil
 	}
 }
@@ -64,7 +64,7 @@ func (t *ActivityTimer) SetTimeout(timeout time.Duration) {
 	t.Lock()
 
 	if t.checkTask != nil {
-		t.checkTask.Close() // nolint: errcheck
+		t.checkTask.Close()
 	}
 	t.checkTask = checkTask
 	t.Unlock()
diff --git a/common/task/periodic.go b/common/task/periodic.go
index a646300f8..6abe41ae0 100644
--- a/common/task/periodic.go
+++ b/common/task/periodic.go
@@ -44,7 +44,7 @@ func (t *Periodic) checkedExecute() error {
 	}
 
 	t.timer = time.AfterFunc(t.Interval, func() {
-		t.checkedExecute() // nolint: errcheck
+		t.checkedExecute()
 	})
 
 	return nil
diff --git a/features/policy/policy.go b/features/policy/policy.go
index b00ffeb78..64f556984 100644
--- a/features/policy/policy.go
+++ b/features/policy/policy.go
@@ -117,8 +117,8 @@ func defaultBufferPolicy() Buffer {
 func SessionDefault() Session {
 	return Session{
 		Timeouts: Timeout{
-			//Align Handshake timeout with nginx client_header_timeout
-			//So that this value will not indicate server identity
+			// Align Handshake timeout with nginx client_header_timeout
+			// So that this value will not indicate server identity
 			Handshake:      time.Second * 60,
 			ConnectionIdle: time.Second * 300,
 			UplinkOnly:     time.Second * 1,
diff --git a/infra/conf/api.go b/infra/conf/api.go
index 4ddfe37b6..0e165c2c4 100644
--- a/infra/conf/api.go
+++ b/infra/conf/api.go
@@ -10,14 +10,14 @@ import (
 	"v2ray.com/core/common/serial"
 )
 
-type ApiConfig struct {
+type APIConfig struct {
 	Tag      string   `json:"tag"`
 	Services []string `json:"services"`
 }
 
-func (c *ApiConfig) Build() (*commander.Config, error) {
+func (c *APIConfig) Build() (*commander.Config, error) {
 	if c.Tag == "" {
-		return nil, newError("Api tag can't be empty.")
+		return nil, newError("API tag can't be empty.")
 	}
 
 	services := make([]*serial.TypedMessage, 0, 16)
diff --git a/infra/conf/blackhole.go b/infra/conf/blackhole.go
index bd0ebf02c..a0eeec430 100644
--- a/infra/conf/blackhole.go
+++ b/infra/conf/blackhole.go
@@ -15,9 +15,9 @@ func (*NoneResponse) Build() (proto.Message, error) {
 	return new(blackhole.NoneResponse), nil
 }
 
-type HttpResponse struct{}
+type HTTPResponse struct{}
 
-func (*HttpResponse) Build() (proto.Message, error) {
+func (*HTTPResponse) Build() (proto.Message, error) {
 	return new(blackhole.HTTPResponse), nil
 }
 
@@ -46,7 +46,7 @@ var (
 	configLoader = NewJSONConfigLoader(
 		ConfigCreatorCache{
 			"none": func() interface{} { return new(NoneResponse) },
-			"http": func() interface{} { return new(HttpResponse) },
+			"http": func() interface{} { return new(HTTPResponse) },
 		},
 		"type",
 		"")
diff --git a/infra/conf/common.go b/infra/conf/common.go
index b97a200ac..03ec6749a 100644
--- a/infra/conf/common.go
+++ b/infra/conf/common.go
@@ -221,7 +221,7 @@ func (list *PortList) UnmarshalJSON(data []byte) error {
 		}
 	}
 	if number != 0 {
-		list.Range = append(list.Range, PortRange{From: uint32(number), To: uint32(number)})
+		list.Range = append(list.Range, PortRange{From: number, To: number})
 	}
 	return nil
 }
diff --git a/infra/conf/common_test.go b/infra/conf/common_test.go
index b73dcbf47..e50c165ca 100644
--- a/infra/conf/common_test.go
+++ b/infra/conf/common_test.go
@@ -2,31 +2,31 @@ package conf_test
 
 import (
 	"encoding/json"
-	"github.com/google/go-cmp/cmp/cmpopts"
 	"os"
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
-	"v2ray.com/core/common/protocol"
+	"github.com/google/go-cmp/cmp/cmpopts"
 
 	"v2ray.com/core/common"
 	"v2ray.com/core/common/net"
+	"v2ray.com/core/common/protocol"
 	. "v2ray.com/core/infra/conf"
 )
 
 func TestStringListUnmarshalError(t *testing.T) {
-	rawJson := `1234`
+	rawJSON := `1234`
 	list := new(StringList)
-	err := json.Unmarshal([]byte(rawJson), list)
+	err := json.Unmarshal([]byte(rawJSON), list)
 	if err == nil {
 		t.Error("expected error, but got nil")
 	}
 }
 
 func TestStringListLen(t *testing.T) {
-	rawJson := `"a, b, c, d"`
+	rawJSON := `"a, b, c, d"`
 	var list StringList
-	err := json.Unmarshal([]byte(rawJson), &list)
+	err := json.Unmarshal([]byte(rawJSON), &list)
 	common.Must(err)
 	if r := cmp.Diff([]string(list), []string{"a", " b", " c", " d"}); r != "" {
 		t.Error(r)
@@ -34,9 +34,9 @@ func TestStringListLen(t *testing.T) {
 }
 
 func TestIPParsing(t *testing.T) {
-	rawJson := "\"8.8.8.8\""
+	rawJSON := "\"8.8.8.8\""
 	var address Address
-	err := json.Unmarshal([]byte(rawJson), &address)
+	err := json.Unmarshal([]byte(rawJSON), &address)
 	common.Must(err)
 	if r := cmp.Diff(address.IP(), net.IP{8, 8, 8, 8}); r != "" {
 		t.Error(r)
@@ -44,9 +44,9 @@ func TestIPParsing(t *testing.T) {
 }
 
 func TestDomainParsing(t *testing.T) {
-	rawJson := "\"v2ray.com\""
+	rawJSON := "\"v2ray.com\""
 	var address Address
-	common.Must(json.Unmarshal([]byte(rawJson), &address))
+	common.Must(json.Unmarshal([]byte(rawJSON), &address))
 	if address.Domain() != "v2ray.com" {
 		t.Error("domain: ", address.Domain())
 	}
@@ -54,17 +54,17 @@ func TestDomainParsing(t *testing.T) {
 
 func TestURLParsing(t *testing.T) {
 	{
-		rawJson := "\"https://dns.google/dns-query\""
+		rawJSON := "\"https://dns.google/dns-query\""
 		var address Address
-		common.Must(json.Unmarshal([]byte(rawJson), &address))
+		common.Must(json.Unmarshal([]byte(rawJSON), &address))
 		if address.Domain() != "https://dns.google/dns-query" {
 			t.Error("URL: ", address.Domain())
 		}
 	}
 	{
-		rawJson := "\"https+local://dns.google/dns-query\""
+		rawJSON := "\"https+local://dns.google/dns-query\""
 		var address Address
-		common.Must(json.Unmarshal([]byte(rawJson), &address))
+		common.Must(json.Unmarshal([]byte(rawJSON), &address))
 		if address.Domain() != "https+local://dns.google/dns-query" {
 			t.Error("URL: ", address.Domain())
 		}
@@ -72,9 +72,9 @@ func TestURLParsing(t *testing.T) {
 }
 
 func TestInvalidAddressJson(t *testing.T) {
-	rawJson := "1234"
+	rawJSON := "1234"
 	var address Address
-	err := json.Unmarshal([]byte(rawJson), &address)
+	err := json.Unmarshal([]byte(rawJSON), &address)
 	if err == nil {
 		t.Error("nil error")
 	}
diff --git a/infra/conf/dns.go b/infra/conf/dns.go
index e9222a4c0..1487f3fd7 100644
--- a/infra/conf/dns.go
+++ b/infra/conf/dns.go
@@ -106,8 +106,8 @@ var typeMap = map[router.Domain_Type]dns.DomainMatchingType{
 	router.Domain_Regex:  dns.DomainMatchingType_Regex,
 }
 
-// DnsConfig is a JSON serializable object for dns.Config.
-type DnsConfig struct {
+// DNSConfig is a JSON serializable object for dns.Config.
+type DNSConfig struct {
 	Servers  []*NameServerConfig `json:"servers"`
 	Hosts    map[string]*Address `json:"hosts"`
 	ClientIP *Address            `json:"clientIp"`
@@ -127,7 +127,7 @@ func getHostMapping(addr *Address) *dns.Config_HostMapping {
 }
 
 // Build implements Buildable
-func (c *DnsConfig) Build() (*dns.Config, error) {
+func (c *DNSConfig) Build() (*dns.Config, error) {
 	config := &dns.Config{
 		Tag: c.Tag,
 	}
@@ -153,16 +153,18 @@ func (c *DnsConfig) Build() (*dns.Config, error) {
 			domains = append(domains, domain)
 		}
 		sort.Strings(domains)
+
 		for _, domain := range domains {
 			addr := c.Hosts[domain]
 			var mappings []*dns.Config_HostMapping
-			if strings.HasPrefix(domain, "domain:") {
+			switch {
+			case strings.HasPrefix(domain, "domain:"):
 				mapping := getHostMapping(addr)
 				mapping.Type = dns.DomainMatchingType_Subdomain
 				mapping.Domain = domain[7:]
-
 				mappings = append(mappings, mapping)
-			} else if strings.HasPrefix(domain, "geosite:") {
+
+			case strings.HasPrefix(domain, "geosite:"):
 				domains, err := loadGeositeWithAttr("geosite.dat", strings.ToUpper(domain[8:]))
 				if err != nil {
 					return nil, newError("invalid geosite settings: ", domain).Base(err)
@@ -171,28 +173,28 @@ func (c *DnsConfig) Build() (*dns.Config, error) {
 					mapping := getHostMapping(addr)
 					mapping.Type = typeMap[d.Type]
 					mapping.Domain = d.Value
-
 					mappings = append(mappings, mapping)
 				}
-			} else if strings.HasPrefix(domain, "regexp:") {
+
+			case strings.HasPrefix(domain, "regexp:"):
 				mapping := getHostMapping(addr)
 				mapping.Type = dns.DomainMatchingType_Regex
 				mapping.Domain = domain[7:]
-
 				mappings = append(mappings, mapping)
-			} else if strings.HasPrefix(domain, "keyword:") {
+
+			case strings.HasPrefix(domain, "keyword:"):
 				mapping := getHostMapping(addr)
 				mapping.Type = dns.DomainMatchingType_Keyword
 				mapping.Domain = domain[8:]
-
 				mappings = append(mappings, mapping)
-			} else if strings.HasPrefix(domain, "full:") {
+
+			case strings.HasPrefix(domain, "full:"):
 				mapping := getHostMapping(addr)
 				mapping.Type = dns.DomainMatchingType_Full
 				mapping.Domain = domain[5:]
-
 				mappings = append(mappings, mapping)
-			} else if strings.HasPrefix(domain, "dotless:") {
+
+			case strings.HasPrefix(domain, "dotless:"):
 				mapping := getHostMapping(addr)
 				mapping.Type = dns.DomainMatchingType_Regex
 				switch substr := domain[8:]; {
@@ -203,9 +205,9 @@ func (c *DnsConfig) Build() (*dns.Config, error) {
 				default:
 					return nil, newError("substr in dotless rule should not contain a dot: ", substr)
 				}
-
 				mappings = append(mappings, mapping)
-			} else if strings.HasPrefix(domain, "ext:") {
+
+			case strings.HasPrefix(domain, "ext:"):
 				kv := strings.Split(domain[4:], ":")
 				if len(kv) != 2 {
 					return nil, newError("invalid external resource: ", domain)
@@ -220,14 +222,13 @@ func (c *DnsConfig) Build() (*dns.Config, error) {
 					mapping := getHostMapping(addr)
 					mapping.Type = typeMap[d.Type]
 					mapping.Domain = d.Value
-
 					mappings = append(mappings, mapping)
 				}
-			} else {
+
+			default:
 				mapping := getHostMapping(addr)
 				mapping.Type = dns.DomainMatchingType_Full
 				mapping.Domain = domain
-
 				mappings = append(mappings, mapping)
 			}
 
diff --git a/infra/conf/dns_proxy.go b/infra/conf/dns_proxy.go
index 4617ead5e..2333892f3 100644
--- a/infra/conf/dns_proxy.go
+++ b/infra/conf/dns_proxy.go
@@ -6,13 +6,13 @@ import (
 	"v2ray.com/core/proxy/dns"
 )
 
-type DnsOutboundConfig struct {
+type DNSOutboundConfig struct {
 	Network Network  `json:"network"`
 	Address *Address `json:"address"`
 	Port    uint16   `json:"port"`
 }
 
-func (c *DnsOutboundConfig) Build() (proto.Message, error) {
+func (c *DNSOutboundConfig) Build() (proto.Message, error) {
 	config := &dns.Config{
 		Server: &net.Endpoint{
 			Network: c.Network.Build(),
diff --git a/infra/conf/dns_proxy_test.go b/infra/conf/dns_proxy_test.go
index 1ecc22626..64351929f 100644
--- a/infra/conf/dns_proxy_test.go
+++ b/infra/conf/dns_proxy_test.go
@@ -10,7 +10,7 @@ import (
 
 func TestDnsProxyConfig(t *testing.T) {
 	creator := func() Buildable {
-		return new(DnsOutboundConfig)
+		return new(DNSOutboundConfig)
 	}
 
 	runMultiTestCase(t, []TestCase{
diff --git a/infra/conf/dns_test.go b/infra/conf/dns_test.go
index ca5a037ff..5afd33b73 100644
--- a/infra/conf/dns_test.go
+++ b/infra/conf/dns_test.go
@@ -45,7 +45,7 @@ func init() {
 	common.Must(err)
 	common.Must2(geositeFile.Write(listBytes))
 }
-func TestDnsConfigParsing(t *testing.T) {
+func TestDNSConfigParsing(t *testing.T) {
 	geositePath := platform.GetAssetLocation("geosite.dat")
 	defer func() {
 		os.Remove(geositePath)
@@ -54,7 +54,7 @@ func TestDnsConfigParsing(t *testing.T) {
 
 	parserCreator := func() func(string) (proto.Message, error) {
 		return func(s string) (proto.Message, error) {
-			config := new(DnsConfig)
+			config := new(DNSConfig)
 			if err := json.Unmarshal([]byte(s), config); err != nil {
 				return nil, err
 			}
diff --git a/infra/conf/http.go b/infra/conf/http.go
index d17537244..e3e2b8f8d 100644
--- a/infra/conf/http.go
+++ b/infra/conf/http.go
@@ -9,26 +9,26 @@ import (
 	"v2ray.com/core/proxy/http"
 )
 
-type HttpAccount struct {
+type HTTPAccount struct {
 	Username string `json:"user"`
 	Password string `json:"pass"`
 }
 
-func (v *HttpAccount) Build() *http.Account {
+func (v *HTTPAccount) Build() *http.Account {
 	return &http.Account{
 		Username: v.Username,
 		Password: v.Password,
 	}
 }
 
-type HttpServerConfig struct {
+type HTTPServerConfig struct {
 	Timeout     uint32         `json:"timeout"`
-	Accounts    []*HttpAccount `json:"accounts"`
+	Accounts    []*HTTPAccount `json:"accounts"`
 	Transparent bool           `json:"allowTransparent"`
 	UserLevel   uint32         `json:"userLevel"`
 }
 
-func (c *HttpServerConfig) Build() (proto.Message, error) {
+func (c *HTTPServerConfig) Build() (proto.Message, error) {
 	config := &http.ServerConfig{
 		Timeout:          c.Timeout,
 		AllowTransparent: c.Transparent,
@@ -45,16 +45,16 @@ func (c *HttpServerConfig) Build() (proto.Message, error) {
 	return config, nil
 }
 
-type HttpRemoteConfig struct {
+type HTTPRemoteConfig struct {
 	Address *Address          `json:"address"`
 	Port    uint16            `json:"port"`
 	Users   []json.RawMessage `json:"users"`
 }
-type HttpClientConfig struct {
-	Servers []*HttpRemoteConfig `json:"servers"`
+type HTTPClientConfig struct {
+	Servers []*HTTPRemoteConfig `json:"servers"`
 }
 
-func (v *HttpClientConfig) Build() (proto.Message, error) {
+func (v *HTTPClientConfig) Build() (proto.Message, error) {
 	config := new(http.ClientConfig)
 	config.Server = make([]*protocol.ServerEndpoint, len(v.Servers))
 	for idx, serverConfig := range v.Servers {
@@ -67,7 +67,7 @@ func (v *HttpClientConfig) Build() (proto.Message, error) {
 			if err := json.Unmarshal(rawUser, user); err != nil {
 				return nil, newError("failed to parse HTTP user").Base(err).AtError()
 			}
-			account := new(HttpAccount)
+			account := new(HTTPAccount)
 			if err := json.Unmarshal(rawUser, account); err != nil {
 				return nil, newError("failed to parse HTTP account").Base(err).AtError()
 			}
diff --git a/infra/conf/http_test.go b/infra/conf/http_test.go
index 87dd4f097..2780f92d1 100644
--- a/infra/conf/http_test.go
+++ b/infra/conf/http_test.go
@@ -7,9 +7,9 @@ import (
 	"v2ray.com/core/proxy/http"
 )
 
-func TestHttpServerConfig(t *testing.T) {
+func TestHTTPServerConfig(t *testing.T) {
 	creator := func() Buildable {
-		return new(HttpServerConfig)
+		return new(HTTPServerConfig)
 	}
 
 	runMultiTestCase(t, []TestCase{
diff --git a/infra/conf/json/reader_test.go b/infra/conf/json/reader_test.go
index 900abcb20..44d8623e2 100644
--- a/infra/conf/json/reader_test.go
+++ b/infra/conf/json/reader_test.go
@@ -93,5 +93,4 @@ func TestReader1(t *testing.T) {
 			t.Error("got ", string(target), " want ", testCase.output)
 		}
 	}
-
 }
diff --git a/infra/conf/policy_test.go b/infra/conf/policy_test.go
index ce6d4daf2..097181052 100644
--- a/infra/conf/policy_test.go
+++ b/infra/conf/policy_test.go
@@ -27,7 +27,7 @@ func TestBufferSize(t *testing.T) {
 	}
 
 	for _, c := range cases {
-		bs := int32(c.Input)
+		bs := c.Input
 		pConf := Policy{
 			BufferSize: &bs,
 		}
diff --git a/infra/conf/router.go b/infra/conf/router.go
index 10b51993f..80afcde33 100644
--- a/infra/conf/router.go
+++ b/infra/conf/router.go
@@ -5,11 +5,11 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/golang/protobuf/proto"
+
 	"v2ray.com/core/app/router"
 	"v2ray.com/core/common/net"
 	"v2ray.com/core/common/platform/filesystem"
-
-	"github.com/golang/protobuf/proto"
 )
 
 type RouterRulesConfig struct {
@@ -67,10 +67,15 @@ func (c *RouterConfig) Build() (*router.Config, error) {
 	config := new(router.Config)
 	config.DomainStrategy = c.getDomainStrategy()
 
-	rawRuleList := c.RuleList
-	if c.Settings != nil {
-		rawRuleList = append(c.RuleList, c.Settings.RuleList...)
+	var rawRuleList []json.RawMessage
+	if c != nil {
+		rawRuleList = c.RuleList
+		if c.Settings != nil {
+			c.RuleList = append(c.RuleList, c.Settings.RuleList...)
+			rawRuleList = c.RuleList
+		}
 	}
+
 	for _, rawRule := range rawRuleList {
 		rule, err := ParseRule(rawRule)
 		if err != nil {
@@ -290,15 +295,19 @@ func parseDomainRule(domain string) ([]*router.Domain, error) {
 	case strings.HasPrefix(domain, "regexp:"):
 		domainRule.Type = router.Domain_Regex
 		domainRule.Value = domain[7:]
+
 	case strings.HasPrefix(domain, "domain:"):
 		domainRule.Type = router.Domain_Domain
 		domainRule.Value = domain[7:]
+
 	case strings.HasPrefix(domain, "full:"):
 		domainRule.Type = router.Domain_Full
 		domainRule.Value = domain[5:]
+
 	case strings.HasPrefix(domain, "keyword:"):
 		domainRule.Type = router.Domain_Plain
 		domainRule.Value = domain[8:]
+
 	case strings.HasPrefix(domain, "dotless:"):
 		domainRule.Type = router.Domain_Regex
 		switch substr := domain[8:]; {
@@ -309,6 +318,7 @@ func parseDomainRule(domain string) ([]*router.Domain, error) {
 		default:
 			return nil, newError("substr in dotless rule should not contain a dot: ", substr)
 		}
+
 	default:
 		domainRule.Type = router.Domain_Plain
 		domainRule.Value = domain
@@ -403,15 +413,16 @@ func parseFieldRule(msg json.RawMessage) (*router.RoutingRule, error) {
 	}
 
 	rule := new(router.RoutingRule)
-	if len(rawFieldRule.OutboundTag) > 0 {
+	switch {
+	case len(rawFieldRule.OutboundTag) > 0:
 		rule.TargetTag = &router.RoutingRule_Tag{
 			Tag: rawFieldRule.OutboundTag,
 		}
-	} else if len(rawFieldRule.BalancerTag) > 0 {
+	case len(rawFieldRule.BalancerTag) > 0:
 		rule.TargetTag = &router.RoutingRule_BalancingTag{
 			BalancingTag: rawFieldRule.BalancerTag,
 		}
-	} else {
+	default:
 		return nil, newError("neither outboundTag nor balancerTag is specified in routing rule")
 	}
 
diff --git a/infra/conf/socks.go b/infra/conf/socks.go
index cba5989a6..1d382788b 100644
--- a/infra/conf/socks.go
+++ b/infra/conf/socks.go
@@ -43,7 +43,7 @@ func (v *SocksServerConfig) Build() (proto.Message, error) {
 	case AuthMethodUserPass:
 		config.AuthType = socks.AuthType_PASSWORD
 	default:
-		//newError("unknown socks auth method: ", v.AuthMethod, ". Default to noauth.").AtWarning().WriteToLog()
+		// newError("unknown socks auth method: ", v.AuthMethod, ". Default to noauth.").AtWarning().WriteToLog()
 		config.AuthType = socks.AuthType_NO_AUTH
 	}
 
diff --git a/infra/conf/transport_authenticators.go b/infra/conf/transport_authenticators.go
index 29092d3a4..989060fdb 100644
--- a/infra/conf/transport_authenticators.go
+++ b/infra/conf/transport_authenticators.go
@@ -56,7 +56,7 @@ func (DTLSAuthenticator) Build() (proto.Message, error) {
 	return new(tls.PacketConfig), nil
 }
 
-type HTTPAuthenticatorRequest struct {
+type AuthenticatorRequest struct {
 	Version string                 `json:"version"`
 	Method  string                 `json:"method"`
 	Path    StringList             `json:"path"`
@@ -72,7 +72,7 @@ func sortMapKeys(m map[string]*StringList) []string {
 	return keys
 }
 
-func (v *HTTPAuthenticatorRequest) Build() (*http.RequestConfig, error) {
+func (v *AuthenticatorRequest) Build() (*http.RequestConfig, error) {
 	config := &http.RequestConfig{
 		Uri: []string{"/"},
 		Header: []*http.Header{
@@ -132,14 +132,14 @@ func (v *HTTPAuthenticatorRequest) Build() (*http.RequestConfig, error) {
 	return config, nil
 }
 
-type HTTPAuthenticatorResponse struct {
+type AuthenticatorResponse struct {
 	Version string                 `json:"version"`
 	Status  string                 `json:"status"`
 	Reason  string                 `json:"reason"`
 	Headers map[string]*StringList `json:"headers"`
 }
 
-func (v *HTTPAuthenticatorResponse) Build() (*http.ResponseConfig, error) {
+func (v *AuthenticatorResponse) Build() (*http.ResponseConfig, error) {
 	config := &http.ResponseConfig{
 		Header: []*http.Header{
 			{
@@ -200,12 +200,12 @@ func (v *HTTPAuthenticatorResponse) Build() (*http.ResponseConfig, error) {
 	return config, nil
 }
 
-type HTTPAuthenticator struct {
-	Request  HTTPAuthenticatorRequest  `json:"request"`
-	Response HTTPAuthenticatorResponse `json:"response"`
+type Authenticator struct {
+	Request  AuthenticatorRequest  `json:"request"`
+	Response AuthenticatorResponse `json:"response"`
 }
 
-func (v *HTTPAuthenticator) Build() (proto.Message, error) {
+func (v *Authenticator) Build() (proto.Message, error) {
 	config := new(http.Config)
 	requestConfig, err := v.Request.Build()
 	if err != nil {
diff --git a/infra/conf/transport_internet.go b/infra/conf/transport_internet.go
index 3906badda..38d16d203 100644
--- a/infra/conf/transport_internet.go
+++ b/infra/conf/transport_internet.go
@@ -31,7 +31,7 @@ var (
 
 	tcpHeaderLoader = NewJSONConfigLoader(ConfigCreatorCache{
 		"none": func() interface{} { return new(NoOpConnectionAuthenticator) },
-		"http": func() interface{} { return new(HTTPAuthenticator) },
+		"http": func() interface{} { return new(Authenticator) },
 	}, "type", "")
 )
 
@@ -473,7 +473,7 @@ func (c *StreamConfig) Build() (*internet.StreamConfig, error) {
 		ProtocolName: "tcp",
 	}
 	if c.Network != nil {
-		protocol, err := (*c.Network).Build()
+		protocol, err := c.Network.Build()
 		if err != nil {
 			return nil, err
 		}
diff --git a/infra/conf/trojan.go b/infra/conf/trojan.go
index 88fd605d9..baaf337ec 100644
--- a/infra/conf/trojan.go
+++ b/infra/conf/trojan.go
@@ -6,7 +6,7 @@ import (
 	"strconv"
 	"syscall"
 
-	"github.com/golang/protobuf/proto" // nolint: staticcheck
+	"github.com/golang/protobuf/proto"
 
 	"v2ray.com/core/common/net"
 	"v2ray.com/core/common/protocol"
diff --git a/infra/conf/v2ray.go b/infra/conf/v2ray.go
index 8625f1f53..92137b3c8 100644
--- a/infra/conf/v2ray.go
+++ b/infra/conf/v2ray.go
@@ -17,7 +17,7 @@ import (
 var (
 	inboundConfigLoader = NewJSONConfigLoader(ConfigCreatorCache{
 		"dokodemo-door": func() interface{} { return new(DokodemoConfig) },
-		"http":          func() interface{} { return new(HttpServerConfig) },
+		"http":          func() interface{} { return new(HTTPServerConfig) },
 		"shadowsocks":   func() interface{} { return new(ShadowsocksServerConfig) },
 		"socks":         func() interface{} { return new(SocksServerConfig) },
 		"vless":         func() interface{} { return new(VLessInboundConfig) },
@@ -29,14 +29,14 @@ var (
 	outboundConfigLoader = NewJSONConfigLoader(ConfigCreatorCache{
 		"blackhole":   func() interface{} { return new(BlackholeConfig) },
 		"freedom":     func() interface{} { return new(FreedomConfig) },
-		"http":        func() interface{} { return new(HttpClientConfig) },
+		"http":        func() interface{} { return new(HTTPClientConfig) },
 		"shadowsocks": func() interface{} { return new(ShadowsocksClientConfig) },
 		"socks":       func() interface{} { return new(SocksClientConfig) },
 		"vless":       func() interface{} { return new(VLessOutboundConfig) },
 		"vmess":       func() interface{} { return new(VMessOutboundConfig) },
 		"trojan":      func() interface{} { return new(TrojanClientConfig) },
 		"mtproto":     func() interface{} { return new(MTProtoClientConfig) },
-		"dns":         func() interface{} { return new(DnsOutboundConfig) },
+		"dns":         func() interface{} { return new(DNSOutboundConfig) },
 	}, "protocol", "settings")
 
 	ctllog = log.New(os.Stderr, "v2ctl> ", 0)
@@ -315,7 +315,7 @@ type Config struct {
 	Port            uint16                 `json:"port"` // Port of this Point server. Deprecated.
 	LogConfig       *LogConfig             `json:"log"`
 	RouterConfig    *RouterConfig          `json:"routing"`
-	DNSConfig       *DnsConfig             `json:"dns"`
+	DNSConfig       *DNSConfig             `json:"dns"`
 	InboundConfigs  []InboundDetourConfig  `json:"inbounds"`
 	OutboundConfigs []OutboundDetourConfig `json:"outbounds"`
 	InboundConfig   *InboundDetourConfig   `json:"inbound"`        // Deprecated.
@@ -324,7 +324,7 @@ type Config struct {
 	OutboundDetours []OutboundDetourConfig `json:"outboundDetour"` // Deprecated.
 	Transport       *TransportConfig       `json:"transport"`
 	Policy          *PolicyConfig          `json:"policy"`
-	Api             *ApiConfig             `json:"api"`
+	API             *APIConfig             `json:"api"`
 	Stats           *StatsConfig           `json:"stats"`
 	Reverse         *ReverseConfig         `json:"reverse"`
 }
@@ -353,7 +353,6 @@ func (c *Config) findOutboundTag(tag string) int {
 
 // Override method accepts another Config overrides the current attribute
 func (c *Config) Override(o *Config, fn string) {
-
 	// only process the non-deprecated members
 
 	if o.LogConfig != nil {
@@ -371,8 +370,8 @@ func (c *Config) Override(o *Config, fn string) {
 	if o.Policy != nil {
 		c.Policy = o.Policy
 	}
-	if o.Api != nil {
-		c.Api = o.Api
+	if o.API != nil {
+		c.API = o.API
 	}
 	if o.Stats != nil {
 		c.Stats = o.Stats
@@ -460,8 +459,8 @@ func (c *Config) Build() (*core.Config, error) {
 		},
 	}
 
-	if c.Api != nil {
-		apiConf, err := c.Api.Build()
+	if c.API != nil {
+		apiConf, err := c.API.Build()
 		if err != nil {
 			return nil, err
 		}
diff --git a/infra/conf/v2ray_test.go b/infra/conf/v2ray_test.go
index e51a42c58..a26af25ee 100644
--- a/infra/conf/v2ray_test.go
+++ b/infra/conf/v2ray_test.go
@@ -384,10 +384,10 @@ func TestConfig_Override(t *testing.T) {
 			&Config{
 				LogConfig:    &LogConfig{},
 				RouterConfig: &RouterConfig{},
-				DNSConfig:    &DnsConfig{},
+				DNSConfig:    &DNSConfig{},
 				Transport:    &TransportConfig{},
 				Policy:       &PolicyConfig{},
-				Api:          &ApiConfig{},
+				API:          &APIConfig{},
 				Stats:        &StatsConfig{},
 				Reverse:      &ReverseConfig{},
 			},
@@ -395,10 +395,10 @@ func TestConfig_Override(t *testing.T) {
 			&Config{
 				LogConfig:    &LogConfig{},
 				RouterConfig: &RouterConfig{},
-				DNSConfig:    &DnsConfig{},
+				DNSConfig:    &DNSConfig{},
 				Transport:    &TransportConfig{},
 				Policy:       &PolicyConfig{},
-				Api:          &ApiConfig{},
+				API:          &APIConfig{},
 				Stats:        &StatsConfig{},
 				Reverse:      &ReverseConfig{},
 			},
diff --git a/infra/conf/vless.go b/infra/conf/vless.go
index 4939696e6..21fc0ae34 100644
--- a/infra/conf/vless.go
+++ b/infra/conf/vless.go
@@ -33,12 +33,7 @@ type VLessInboundConfig struct {
 
 // Build implements Buildable
 func (c *VLessInboundConfig) Build() (proto.Message, error) {
-
 	config := new(inbound.Config)
-
-	if len(c.Clients) == 0 {
-		//return nil, newError(`VLESS settings: "clients" is empty`)
-	}
 	config.Clients = make([]*protocol.User, len(c.Clients))
 	for idx, rawUser := range c.Clients {
 		user := new(protocol.User)
@@ -142,7 +137,6 @@ type VLessOutboundConfig struct {
 
 // Build implements Buildable
 func (c *VLessOutboundConfig) Build() (proto.Message, error) {
-
 	config := new(outbound.Config)
 
 	if len(c.Vnext) == 0 {
diff --git a/infra/control/api.go b/infra/control/api.go
index 823d49450..8954eb6f9 100644
--- a/infra/control/api.go
+++ b/infra/control/api.go
@@ -16,13 +16,13 @@ import (
 	"v2ray.com/core/common"
 )
 
-type ApiCommand struct{}
+type APICommand struct{}
 
-func (c *ApiCommand) Name() string {
+func (c *APICommand) Name() string {
 	return "api"
 }
 
-func (c *ApiCommand) Description() Description {
+func (c *APICommand) Description() Description {
 	return Description{
 		Short: "Call V2Ray API",
 		Usage: []string{
@@ -42,7 +42,7 @@ func (c *ApiCommand) Description() Description {
 	}
 }
 
-func (c *ApiCommand) Execute(args []string) error {
+func (c *APICommand) Execute(args []string) error {
 	fs := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
 
 	serverAddrPtr := fs.String("server", "127.0.0.1:8080", "Server address")
@@ -154,5 +154,5 @@ func callStatsService(ctx context.Context, conn *grpc.ClientConn, method string,
 }
 
 func init() {
-	common.Must(RegisterCommand(&ApiCommand{}))
+	common.Must(RegisterCommand(&APICommand{}))
 }
diff --git a/infra/control/cert.go b/infra/control/cert.go
index 1cdfd2eed..e39f28696 100644
--- a/infra/control/cert.go
+++ b/infra/control/cert.go
@@ -53,7 +53,7 @@ func (c *CertificateCommand) Description() Description {
 	}
 }
 
-func (c *CertificateCommand) printJson(certificate *cert.Certificate) {
+func (c *CertificateCommand) printJSON(certificate *cert.Certificate) {
 	certPEM, keyPEM := certificate.ToPEM()
 	jCert := &jsonCert{
 		Certificate: strings.Split(strings.TrimSpace(string(certPEM)), "\n"),
@@ -122,7 +122,7 @@ func (c *CertificateCommand) Execute(args []string) error {
 	}
 
 	if *jsonOutput {
-		c.printJson(cert)
+		c.printJSON(cert)
 	}
 
 	if len(*fileOutput) > 0 {
diff --git a/infra/control/config.go b/infra/control/config.go
index 504975a8c..5738cc9dd 100644
--- a/infra/control/config.go
+++ b/infra/control/config.go
@@ -66,13 +66,15 @@ func (c *ConfigCommand) Execute(args []string) error {
 
 // LoadArg loads one arg, maybe an remote url, or local file path
 func (c *ConfigCommand) LoadArg(arg string) (out io.Reader, err error) {
-
 	var data []byte
-	if strings.HasPrefix(arg, "http://") || strings.HasPrefix(arg, "https://") {
+	switch {
+	case strings.HasPrefix(arg, "http://"), strings.HasPrefix(arg, "https://"):
 		data, err = FetchHTTPContent(arg)
-	} else if arg == "stdin:" {
+
+	case arg == "stdin:":
 		data, err = ioutil.ReadAll(os.Stdin)
-	} else {
+
+	default:
 		data, err = ioutil.ReadFile(arg)
 	}
 
diff --git a/infra/control/fetch.go b/infra/control/fetch.go
index a9deef25f..30830ae2f 100644
--- a/infra/control/fetch.go
+++ b/infra/control/fetch.go
@@ -39,7 +39,6 @@ func (c *FetchCommand) Execute(args []string) error {
 
 // FetchHTTPContent dials https for remote content
 func FetchHTTPContent(target string) ([]byte, error) {
-
 	parsedTarget, err := url.Parse(target)
 	if err != nil {
 		return nil, newError("invalid URL: ", target).Base(err)
diff --git a/infra/control/tlsping.go b/infra/control/tlsping.go
index 2bd20b0d8..de57a5d28 100644
--- a/infra/control/tlsping.go
+++ b/infra/control/tlsping.go
@@ -10,13 +10,13 @@ import (
 	"v2ray.com/core/common"
 )
 
-type TlsPingCommand struct{}
+type TLSPingCommand struct{}
 
-func (c *TlsPingCommand) Name() string {
+func (c *TLSPingCommand) Name() string {
 	return "tlsping"
 }
 
-func (c *TlsPingCommand) Description() Description {
+func (c *TLSPingCommand) Description() Description {
 	return Description{
 		Short: "Ping the domain with TLS handshake",
 		Usage: []string{"v2ctl tlsping <domain> --ip <ip>"},
@@ -32,7 +32,7 @@ func printCertificates(certs []*x509.Certificate) {
 	}
 }
 
-func (c *TlsPingCommand) Execute(args []string) error {
+func (c *TLSPingCommand) Execute(args []string) error {
 	fs := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
 	ipStr := fs.String("ip", "", "IP address of the domain")
 
@@ -115,5 +115,5 @@ func (c *TlsPingCommand) Execute(args []string) error {
 }
 
 func init() {
-	common.Must(RegisterCommand(&TlsPingCommand{}))
+	common.Must(RegisterCommand(&TLSPingCommand{}))
 }
diff --git a/infra/control/verify.go b/infra/control/verify.go
index 1a4ee2818..5c7064b52 100644
--- a/infra/control/verify.go
+++ b/infra/control/verify.go
@@ -2,8 +2,9 @@ package control
 
 import (
 	"flag"
-	"github.com/xiaokangwang/VSign/signerVerify"
 	"os"
+
+	"github.com/xiaokangwang/VSign/signerVerify"
 	"v2ray.com/core/common"
 )
 
diff --git a/main/confloader/external/external.go b/main/confloader/external/external.go
index f6bcf7d5b..84c00cbe9 100644
--- a/main/confloader/external/external.go
+++ b/main/confloader/external/external.go
@@ -18,13 +18,15 @@ import (
 )
 
 func ConfigLoader(arg string) (out io.Reader, err error) {
-
 	var data []byte
-	if strings.HasPrefix(arg, "http://") || strings.HasPrefix(arg, "https://") {
+	switch {
+	case strings.HasPrefix(arg, "http://"), strings.HasPrefix(arg, "https://"):
 		data, err = FetchHTTPContent(arg)
-	} else if arg == "stdin:" {
+
+	case arg == "stdin:":
 		data, err = ioutil.ReadAll(os.Stdin)
-	} else {
+
+	default:
 		data, err = ioutil.ReadFile(arg)
 	}
 
@@ -36,7 +38,6 @@ func ConfigLoader(arg string) (out io.Reader, err error) {
 }
 
 func FetchHTTPContent(target string) ([]byte, error) {
-
 	parsedTarget, err := url.Parse(target)
 	if err != nil {
 		return nil, newError("invalid URL: ", target).Base(err)
diff --git a/main/distro/debug/debug.go b/main/distro/debug/debug.go
index f005c5b37..7448ecdfe 100644
--- a/main/distro/debug/debug.go
+++ b/main/distro/debug/debug.go
@@ -1,7 +1,8 @@
 package debug
 
-import _ "net/http/pprof"
-import "net/http"
+import (
+	"net/http"
+)
 
 func init() {
 	go func() {
diff --git a/main/main.go b/main/main.go
index 8390af3e7..de6f3890d 100644
--- a/main/main.go
+++ b/main/main.go
@@ -70,11 +70,9 @@ func getConfigFilePath() (cmdarg.Arg, error) {
 	if dirExists(configDir) {
 		log.Println("Using confdir from arg:", configDir)
 		readConfDir(configDir)
-	} else {
-		if envConfDir := platform.GetConfDirPath(); dirExists(envConfDir) {
-			log.Println("Using confdir from env:", envConfDir)
-			readConfDir(envConfDir)
-		}
+	} else if envConfDir := platform.GetConfDirPath(); dirExists(envConfDir) {
+		log.Println("Using confdir from env:", envConfDir)
+		readConfDir(envConfDir)
 	}
 
 	if len(configFiles) > 0 {
@@ -134,7 +132,6 @@ func printVersion() {
 }
 
 func main() {
-
 	flag.Parse()
 
 	printVersion()
diff --git a/proxy/blackhole/blackhole.go b/proxy/blackhole/blackhole.go
index d2213390b..00b12a222 100644
--- a/proxy/blackhole/blackhole.go
+++ b/proxy/blackhole/blackhole.go
@@ -1,7 +1,6 @@
 // +build !confonly
 
 // Package blackhole is an outbound handler that blocks all connections.
-
 package blackhole
 
 //go:generate go run v2ray.com/core/common/errors/errorgen
diff --git a/proxy/blackhole/config_test.go b/proxy/blackhole/config_test.go
index 340ddcc27..d67ac87fe 100644
--- a/proxy/blackhole/config_test.go
+++ b/proxy/blackhole/config_test.go
@@ -19,6 +19,7 @@ func TestHTTPResponse(t *testing.T) {
 	reader := bufio.NewReader(buffer)
 	response, err := http.ReadResponse(reader, nil)
 	common.Must(err)
+
 	if response.StatusCode != 403 {
 		t.Error("expected status code 403, but got ", response.StatusCode)
 	}
diff --git a/proxy/dns/dns_test.go b/proxy/dns/dns_test.go
index 7ac7d520d..95833d681 100644
--- a/proxy/dns/dns_test.go
+++ b/proxy/dns/dns_test.go
@@ -44,7 +44,8 @@ func (*staticHandler) ServeDNS(w dns.ResponseWriter, r *dns.Msg) {
 	}
 
 	for _, q := range r.Question {
-		if q.Name == "google.com." && q.Qtype == dns.TypeA {
+		switch {
+		case q.Name == "google.com." && q.Qtype == dns.TypeA:
 			if clientIP == nil {
 				rr, _ := dns.NewRR("google.com. IN A 8.8.8.8")
 				ans.Answer = append(ans.Answer, rr)
@@ -52,18 +53,22 @@ func (*staticHandler) ServeDNS(w dns.ResponseWriter, r *dns.Msg) {
 				rr, _ := dns.NewRR("google.com. IN A 8.8.4.4")
 				ans.Answer = append(ans.Answer, rr)
 			}
-		} else if q.Name == "facebook.com." && q.Qtype == dns.TypeA {
+
+		case q.Name == "facebook.com." && q.Qtype == dns.TypeA:
 			rr, _ := dns.NewRR("facebook.com. IN A 9.9.9.9")
 			ans.Answer = append(ans.Answer, rr)
-		} else if q.Name == "ipv6.google.com." && q.Qtype == dns.TypeA {
+
+		case q.Name == "ipv6.google.com." && q.Qtype == dns.TypeA:
 			rr, err := dns.NewRR("ipv6.google.com. IN A 8.8.8.7")
 			common.Must(err)
 			ans.Answer = append(ans.Answer, rr)
-		} else if q.Name == "ipv6.google.com." && q.Qtype == dns.TypeAAAA {
+
+		case q.Name == "ipv6.google.com." && q.Qtype == dns.TypeAAAA:
 			rr, err := dns.NewRR("ipv6.google.com. IN AAAA 2001:4860:4860::8888")
 			common.Must(err)
 			ans.Answer = append(ans.Answer, rr)
-		} else if q.Name == "notexist.google.com." && q.Qtype == dns.TypeAAAA {
+
+		case q.Name == "notexist.google.com." && q.Qtype == dns.TypeAAAA:
 			ans.MsgHdr.Rcode = dns.RcodeNameError
 		}
 	}
diff --git a/proxy/dokodemo/dokodemo.go b/proxy/dokodemo/dokodemo.go
index 0333eb28c..9185a597f 100644
--- a/proxy/dokodemo/dokodemo.go
+++ b/proxy/dokodemo/dokodemo.go
@@ -156,7 +156,7 @@ func (d *DokodemoDoor) Process(ctx context.Context, network net.Network, conn in
 	if network == net.Network_TCP {
 		writer = buf.NewWriter(conn)
 	} else {
-		//if we are in TPROXY mode, use linux's udp forging functionality
+		// if we are in TPROXY mode, use linux's udp forging functionality
 		if !destinationOverridden {
 			writer = &buf.SequentialWriter{Writer: conn}
 		} else {
diff --git a/proxy/freedom/freedom.go b/proxy/freedom/freedom.go
index 0ac95466c..9a55a71b2 100644
--- a/proxy/freedom/freedom.go
+++ b/proxy/freedom/freedom.go
@@ -137,7 +137,7 @@ func (h *Handler) Process(ctx context.Context, link *transport.Link, dialer inte
 	if err != nil {
 		return newError("failed to open connection to ", destination).Base(err)
 	}
-	defer conn.Close() // nolint: errcheck
+	defer conn.Close()
 
 	plcy := h.policy()
 	ctx, cancel := context.WithCancel(ctx)
diff --git a/proxy/http/server.go b/proxy/http/server.go
index f956438c4..059ea310a 100644
--- a/proxy/http/server.go
+++ b/proxy/http/server.go
@@ -103,7 +103,7 @@ Start:
 	if err != nil {
 		trace := newError("failed to read http request").Base(err)
 		if errors.Cause(err) != io.EOF && !isTimeout(errors.Cause(err)) {
-			trace.AtWarning() // nolint: errcheck
+			trace.AtWarning()
 		}
 		return trace
 	}
@@ -159,7 +159,7 @@ Start:
 	return err
 }
 
-func (s *Server) handleConnect(ctx context.Context, request *http.Request, reader *bufio.Reader, conn internet.Connection, dest net.Destination, dispatcher routing.Dispatcher) error {
+func (s *Server) handleConnect(ctx context.Context, _ *http.Request, reader *bufio.Reader, conn internet.Connection, dest net.Destination, dispatcher routing.Dispatcher) error {
 	_, err := conn.Write([]byte("HTTP/1.1 200 Connection established\r\n\r\n"))
 	if err != nil {
 		return newError("failed to write back OK response").Base(err)
@@ -263,7 +263,7 @@ func (s *Server) handlePlainHTTP(ctx context.Context, request *http.Request, wri
 	}
 
 	// Plain HTTP request is not a stream. The request always finishes before response. Hense request has to be closed later.
-	defer common.Close(link.Writer) // nolint: errcheck
+	defer common.Close(link.Writer)
 	var result error = errWaitAnother
 
 	requestDone := func() error {
diff --git a/proxy/mtproto/client.go b/proxy/mtproto/client.go
index 6db10e048..115b668b2 100644
--- a/proxy/mtproto/client.go
+++ b/proxy/mtproto/client.go
@@ -34,7 +34,7 @@ func (c *Client) Process(ctx context.Context, link *transport.Link, dialer inter
 	if err != nil {
 		return newError("failed to dial to ", dest).Base(err).AtWarning()
 	}
-	defer conn.Close() // nolint: errcheck
+	defer conn.Close()
 
 	sc := SessionContextFromContext(ctx)
 	auth := NewAuthentication(sc)
diff --git a/proxy/shadowsocks/client.go b/proxy/shadowsocks/client.go
index 012e595f1..04b7c723d 100644
--- a/proxy/shadowsocks/client.go
+++ b/proxy/shadowsocks/client.go
@@ -136,7 +136,6 @@ func (c *Client) Process(ctx context.Context, link *transport.Link, dialer inter
 	}
 
 	if request.Command == protocol.RequestCommandUDP {
-
 		writer := &buf.SequentialWriter{Writer: &UDPWriter{
 			Writer:  conn,
 			Request: request,
diff --git a/proxy/shadowsocks/protocol.go b/proxy/shadowsocks/protocol.go
index 4d4fc414d..63f807605 100644
--- a/proxy/shadowsocks/protocol.go
+++ b/proxy/shadowsocks/protocol.go
@@ -6,14 +6,13 @@ import (
 	"crypto/hmac"
 	"crypto/rand"
 	"crypto/sha256"
-	"hash"
 	"hash/crc32"
 	"io"
 	"io/ioutil"
-	"v2ray.com/core/common/dice"
 
 	"v2ray.com/core/common"
 	"v2ray.com/core/common/buf"
+	"v2ray.com/core/common/dice"
 	"v2ray.com/core/common/net"
 	"v2ray.com/core/common/protocol"
 )
@@ -35,7 +34,7 @@ var addrParser = protocol.NewAddressParser(
 func ReadTCPSession(user *protocol.MemoryUser, reader io.Reader) (*protocol.RequestHeader, buf.Reader, error) {
 	account := user.Account.(*MemoryAccount)
 
-	hashkdf := hmac.New(func() hash.Hash { return sha256.New() }, []byte("SSBSKDF"))
+	hashkdf := hmac.New(sha256.New, []byte("SSBSKDF"))
 	hashkdf.Write(account.Key)
 
 	behaviorSeed := crc32.ChecksumIEEE(hashkdf.Sum(nil))
diff --git a/proxy/shadowsocks/protocol_test.go b/proxy/shadowsocks/protocol_test.go
index 60630e29c..10080bfff 100644
--- a/proxy/shadowsocks/protocol_test.go
+++ b/proxy/shadowsocks/protocol_test.go
@@ -133,7 +133,6 @@ func TestTCPRequest(t *testing.T) {
 	for _, test := range cases {
 		runTest(test.request, test.payload)
 	}
-
 }
 
 func TestUDPReaderWriter(t *testing.T) {
diff --git a/proxy/socks/client.go b/proxy/socks/client.go
index a6a345b27..836caf205 100644
--- a/proxy/socks/client.go
+++ b/proxy/socks/client.go
@@ -127,7 +127,7 @@ func (c *Client) Process(ctx context.Context, link *transport.Link, dialer inter
 		if err != nil {
 			return newError("failed to create UDP connection").Base(err)
 		}
-		defer udpConn.Close() // nolint: errcheck
+		defer udpConn.Close()
 		requestFunc = func() error {
 			defer timer.SetTimeout(p.Timeouts.DownlinkOnly)
 			return buf.Copy(link.Reader, &buf.SequentialWriter{Writer: NewUDPWriter(request, udpConn)}, buf.UpdateActivity(timer))
diff --git a/proxy/socks/protocol.go b/proxy/socks/protocol.go
index 6542600e7..47ad3f30f 100644
--- a/proxy/socks/protocol.go
+++ b/proxy/socks/protocol.go
@@ -26,7 +26,7 @@ const (
 	socks4RequestRejected = 91
 
 	authNotRequired = 0x00
-	//authGssAPI           = 0x01
+	// authGssAPI           = 0x01
 	authPassword         = 0x02
 	authNoMatchingMethod = 0xFF
 
@@ -47,7 +47,7 @@ type ServerSession struct {
 
 func (s *ServerSession) handshake4(cmd byte, reader io.Reader, writer io.Writer) (*protocol.RequestHeader, error) {
 	if s.config.AuthType == AuthType_PASSWORD {
-		writeSocks4Response(writer, socks4RequestRejected, net.AnyIP, net.Port(0)) // nolint: errcheck
+		writeSocks4Response(writer, socks4RequestRejected, net.AnyIP, net.Port(0))
 		return nil, newError("socks 4 is not allowed when auth is required.")
 	}
 
@@ -89,7 +89,7 @@ func (s *ServerSession) handshake4(cmd byte, reader io.Reader, writer io.Writer)
 		}
 		return request, nil
 	default:
-		writeSocks4Response(writer, socks4RequestRejected, net.AnyIP, net.Port(0)) // nolint: errcheck
+		writeSocks4Response(writer, socks4RequestRejected, net.AnyIP, net.Port(0))
 		return nil, newError("unsupported command: ", cmd)
 	}
 }
@@ -108,7 +108,7 @@ func (s *ServerSession) auth5(nMethod byte, reader io.Reader, writer io.Writer)
 	}
 
 	if !hasAuthMethod(expectedAuth, buffer.BytesRange(0, int32(nMethod))) {
-		writeSocks5AuthenticationResponse(writer, socks5Version, authNoMatchingMethod) // nolint: errcheck
+		writeSocks5AuthenticationResponse(writer, socks5Version, authNoMatchingMethod)
 		return "", newError("no matching auth method")
 	}
 
@@ -123,7 +123,7 @@ func (s *ServerSession) auth5(nMethod byte, reader io.Reader, writer io.Writer)
 		}
 
 		if !s.config.HasAccount(username, password) {
-			writeSocks5AuthenticationResponse(writer, 0x01, 0xFF) // nolint: errcheck
+			writeSocks5AuthenticationResponse(writer, 0x01, 0xFF)
 			return "", newError("invalid username or password")
 		}
 
@@ -166,15 +166,15 @@ func (s *ServerSession) handshake5(nMethod byte, reader io.Reader, writer io.Wri
 		request.Command = protocol.RequestCommandTCP
 	case cmdUDPPort:
 		if !s.config.UdpEnabled {
-			writeSocks5Response(writer, statusCmdNotSupport, net.AnyIP, net.Port(0)) // nolint: errcheck
+			writeSocks5Response(writer, statusCmdNotSupport, net.AnyIP, net.Port(0))
 			return nil, newError("UDP is not enabled.")
 		}
 		request.Command = protocol.RequestCommandUDP
 	case cmdTCPBind:
-		writeSocks5Response(writer, statusCmdNotSupport, net.AnyIP, net.Port(0)) // nolint: errcheck
+		writeSocks5Response(writer, statusCmdNotSupport, net.AnyIP, net.Port(0))
 		return nil, newError("TCP bind is not supported.")
 	default:
-		writeSocks5Response(writer, statusCmdNotSupport, net.AnyIP, net.Port(0)) // nolint: errcheck
+		writeSocks5Response(writer, statusCmdNotSupport, net.AnyIP, net.Port(0))
 		return nil, newError("unknown command ", cmd)
 	}
 
diff --git a/proxy/socks/server.go b/proxy/socks/server.go
index b91020fff..3f421bb78 100644
--- a/proxy/socks/server.go
+++ b/proxy/socks/server.go
@@ -202,7 +202,7 @@ func (s *Server) handleUDPPayload(ctx context.Context, conn internet.Connection,
 			newError("failed to write UDP response").AtWarning().Base(err).WriteToLog(session.ExportIDToError(ctx))
 		}
 
-		conn.Write(udpMessage.Bytes()) // nolint: errcheck
+		conn.Write(udpMessage.Bytes())
 	})
 
 	if inbound := session.InboundFromContext(ctx); inbound != nil && inbound.Source.IsValid() {
diff --git a/proxy/trojan/client.go b/proxy/trojan/client.go
index bd2758b15..20392c8d1 100644
--- a/proxy/trojan/client.go
+++ b/proxy/trojan/client.go
@@ -49,7 +49,7 @@ func NewClient(ctx context.Context, config *ClientConfig) (*Client, error) {
 }
 
 // Process implements OutboundHandler.Process().
-func (c *Client) Process(ctx context.Context, link *transport.Link, dialer internet.Dialer) error { // nolint: funlen
+func (c *Client) Process(ctx context.Context, link *transport.Link, dialer internet.Dialer) error {
 	outbound := session.OutboundFromContext(ctx)
 	if outbound == nil || !outbound.Target.IsValid() {
 		return newError("target not specified")
@@ -60,7 +60,7 @@ func (c *Client) Process(ctx context.Context, link *transport.Link, dialer inter
 	var server *protocol.ServerSpec
 	var conn internet.Connection
 
-	err := retry.ExponentialBackoff(5, 100).On(func() error { // nolint: gomnd
+	err := retry.ExponentialBackoff(5, 100).On(func() error {
 		server = c.serverPicker.PickServer()
 		rawConn, err := dialer.Dial(ctx, server.Destination())
 		if err != nil {
@@ -101,7 +101,7 @@ func (c *Client) Process(ctx context.Context, link *transport.Link, dialer inter
 		}
 
 		// write some request payload to buffer
-		if err = buf.CopyOnceTimeout(link.Reader, bodyWriter, time.Millisecond*100); err != nil && err != buf.ErrNotTimeoutReader && err != buf.ErrReadTimeout { // nolint: lll,gomnd
+		if err = buf.CopyOnceTimeout(link.Reader, bodyWriter, time.Millisecond*100); err != nil && err != buf.ErrNotTimeoutReader && err != buf.ErrReadTimeout {
 			return newError("failed to write A reqeust payload").Base(err).AtWarning()
 		}
 
@@ -140,7 +140,7 @@ func (c *Client) Process(ctx context.Context, link *transport.Link, dialer inter
 }
 
 func init() {
-	common.Must(common.RegisterConfig((*ClientConfig)(nil), func(ctx context.Context, config interface{}) (interface{}, error) { // nolint: lll
+	common.Must(common.RegisterConfig((*ClientConfig)(nil), func(ctx context.Context, config interface{}) (interface{}, error) {
 		return NewClient(ctx, config.(*ClientConfig))
 	}))
 }
diff --git a/proxy/trojan/protocol.go b/proxy/trojan/protocol.go
index d8007563d..4c13964dc 100644
--- a/proxy/trojan/protocol.go
+++ b/proxy/trojan/protocol.go
@@ -13,9 +13,9 @@ var (
 	crlf = []byte{'\r', '\n'}
 
 	addrParser = protocol.NewAddressParser(
-		protocol.AddressFamilyByte(0x01, net.AddressFamilyIPv4),   // nolint: gomnd
-		protocol.AddressFamilyByte(0x04, net.AddressFamilyIPv6),   // nolint: gomnd
-		protocol.AddressFamilyByte(0x03, net.AddressFamilyDomain), // nolint: gomnd
+		protocol.AddressFamilyByte(0x01, net.AddressFamilyIPv4),
+		protocol.AddressFamilyByte(0x04, net.AddressFamilyIPv6),
+		protocol.AddressFamilyByte(0x03, net.AddressFamilyDomain),
 	)
 )
 
@@ -129,7 +129,7 @@ func (w *PacketWriter) WriteMultiBufferWithMetadata(mb buf.MultiBuffer, dest net
 	return nil
 }
 
-func (w *PacketWriter) writePacket(payload []byte, dest net.Destination) (int, error) { // nolint: unparam
+func (w *PacketWriter) writePacket(payload []byte, dest net.Destination) (int, error) {
 	buffer := buf.StackNew()
 	defer buffer.Release()
 
diff --git a/proxy/trojan/server.go b/proxy/trojan/server.go
index d1248d6f2..ecacdeb68 100644
--- a/proxy/trojan/server.go
+++ b/proxy/trojan/server.go
@@ -29,7 +29,7 @@ import (
 )
 
 func init() {
-	common.Must(common.RegisterConfig((*ServerConfig)(nil), func(ctx context.Context, config interface{}) (interface{}, error) { // nolint: lll
+	common.Must(common.RegisterConfig((*ServerConfig)(nil), func(ctx context.Context, config interface{}) (interface{}, error) {
 		return NewServer(ctx, config.(*ServerConfig))
 	}))
 }
@@ -91,8 +91,7 @@ func (s *Server) Network() []net.Network {
 }
 
 // Process implements proxy.Inbound.Process().
-func (s *Server) Process(ctx context.Context, network net.Network, conn internet.Connection, dispatcher routing.Dispatcher) error { // nolint: funlen,lll
-
+func (s *Server) Process(ctx context.Context, network net.Network, conn internet.Connection, dispatcher routing.Dispatcher) error {
 	sid := session.ExportIDToError(ctx)
 
 	iConn := conn
@@ -125,7 +124,7 @@ func (s *Server) Process(ctx context.Context, network net.Network, conn internet
 	isfb := apfb != nil
 
 	shouldFallback := false
-	if firstLen < 58 || first.Byte(56) != '\r' { // nolint: gomnd
+	if firstLen < 58 || first.Byte(56) != '\r' {
 		// invalid protocol
 		err = newError("not trojan protocol")
 		log.Record(&log.AccessMessage{
@@ -137,7 +136,7 @@ func (s *Server) Process(ctx context.Context, network net.Network, conn internet
 
 		shouldFallback = true
 	} else {
-		user = s.validator.Get(hexString(first.BytesTo(56))) // nolint: gomnd
+		user = s.validator.Get(hexString(first.BytesTo(56)))
 		if user == nil {
 			// invalid user, let's fallback
 			err = newError("not a valid user")
@@ -199,7 +198,7 @@ func (s *Server) Process(ctx context.Context, network net.Network, conn internet
 	return s.handleConnection(ctx, sessionPolicy, destination, clientReader, buf.NewWriter(conn), dispatcher)
 }
 
-func (s *Server) handleUDPPayload(ctx context.Context, clientReader *PacketReader, clientWriter *PacketWriter, dispatcher routing.Dispatcher) error { // nolint: lll
+func (s *Server) handleUDPPayload(ctx context.Context, clientReader *PacketReader, clientWriter *PacketWriter, dispatcher routing.Dispatcher) error {
 	udpServer := udp.NewDispatcher(dispatcher, func(ctx context.Context, packet *udp_proto.Packet) {
 		common.Must(clientWriter.WriteMultiBufferWithMetadata(buf.MultiBuffer{packet.Payload}, packet.Source))
 	})
@@ -277,7 +276,7 @@ func (s *Server) handleConnection(ctx context.Context, sessionPolicy policy.Sess
 	return nil
 }
 
-func (s *Server) fallback(ctx context.Context, sid errors.ExportOption, err error, sessionPolicy policy.Session, connection internet.Connection, iConn internet.Connection, apfb map[string]map[string]*Fallback, first *buf.Buffer, firstLen int64, reader buf.Reader) error { // nolint: lll
+func (s *Server) fallback(ctx context.Context, sid errors.ExportOption, err error, sessionPolicy policy.Session, connection internet.Connection, iConn internet.Connection, apfb map[string]map[string]*Fallback, first *buf.Buffer, firstLen int64, reader buf.Reader) error {
 	if err := connection.SetReadDeadline(time.Time{}); err != nil {
 		newError("unable to set back read deadline").Base(err).AtWarning().WriteToLog(sid)
 	}
diff --git a/proxy/vless/encoding/addons.go b/proxy/vless/encoding/addons.go
index 459cabf8c..c847f0079 100644
--- a/proxy/vless/encoding/addons.go
+++ b/proxy/vless/encoding/addons.go
@@ -13,10 +13,8 @@ import (
 )
 
 func EncodeHeaderAddons(buffer *buf.Buffer, addons *Addons) error {
-
 	switch addons.Flow {
 	case vless.XRO, vless.XRD:
-
 		bytes, err := proto.Marshal(addons)
 		if err != nil {
 			return newError("failed to marshal addons protobuf value").Base(err)
@@ -27,30 +25,23 @@ func EncodeHeaderAddons(buffer *buf.Buffer, addons *Addons) error {
 		if _, err := buffer.Write(bytes); err != nil {
 			return newError("failed to write addons protobuf value").Base(err)
 		}
-
 	default:
-
 		if err := buffer.WriteByte(0); err != nil {
 			return newError("failed to write addons protobuf length").Base(err)
 		}
-
 	}
 
 	return nil
-
 }
 
 func DecodeHeaderAddons(buffer *buf.Buffer, reader io.Reader) (*Addons, error) {
-
 	addons := new(Addons)
-
 	buffer.Clear()
 	if _, err := buffer.ReadFullFrom(reader, 1); err != nil {
 		return nil, newError("failed to read addons protobuf length").Base(err)
 	}
 
 	if length := int32(buffer.Byte(0)); length != 0 {
-
 		buffer.Clear()
 		if _, err := buffer.ReadFullFrom(reader, length); err != nil {
 			return nil, newError("failed to read addons protobuf value").Base(err)
@@ -63,45 +54,32 @@ func DecodeHeaderAddons(buffer *buf.Buffer, reader io.Reader) (*Addons, error) {
 		// Verification.
 		switch addons.Flow {
 		default:
-
 		}
-
 	}
 
 	return addons, nil
-
 }
 
 // EncodeBodyAddons returns a Writer that auto-encrypt content written by caller.
 func EncodeBodyAddons(writer io.Writer, request *protocol.RequestHeader, addons *Addons) buf.Writer {
-
 	switch addons.Flow {
 	default:
-
 		if request.Command == protocol.RequestCommandUDP {
 			return NewMultiLengthPacketWriter(writer.(buf.Writer))
 		}
-
 	}
-
 	return buf.NewWriter(writer)
-
 }
 
 // DecodeBodyAddons returns a Reader from which caller can fetch decrypted body.
 func DecodeBodyAddons(reader io.Reader, request *protocol.RequestHeader, addons *Addons) buf.Reader {
-
 	switch addons.Flow {
 	default:
-
 		if request.Command == protocol.RequestCommandUDP {
 			return NewLengthPacketReader(reader)
 		}
-
 	}
-
 	return buf.NewReader(reader)
-
 }
 
 func NewMultiLengthPacketWriter(writer buf.Writer) *MultiLengthPacketWriter {
@@ -157,7 +135,7 @@ type LengthPacketWriter struct {
 
 func (w *LengthPacketWriter) WriteMultiBuffer(mb buf.MultiBuffer) error {
 	length := mb.Len() // none of mb is nil
-	//fmt.Println("Write", length)
+	// fmt.Println("Write", length)
 	if length == 0 {
 		return nil
 	}
@@ -193,7 +171,7 @@ func (r *LengthPacketReader) ReadMultiBuffer() (buf.MultiBuffer, error) {
 		return nil, newError("failed to read packet length").Base(err)
 	}
 	length := int32(r.cache[0])<<8 | int32(r.cache[1])
-	//fmt.Println("Read", length)
+	// fmt.Println("Read", length)
 	mb := make(buf.MultiBuffer, 0, length/buf.Size+1)
 	for length > 0 {
 		size := length
diff --git a/proxy/vless/encoding/encoding.go b/proxy/vless/encoding/encoding.go
index ec6ecff6c..81a8d512a 100644
--- a/proxy/vless/encoding/encoding.go
+++ b/proxy/vless/encoding/encoding.go
@@ -26,7 +26,6 @@ var addrParser = protocol.NewAddressParser(
 
 // EncodeRequestHeader writes encoded request header into the given writer.
 func EncodeRequestHeader(writer io.Writer, request *protocol.RequestHeader, requestAddons *Addons) error {
-
 	buffer := buf.StackNew()
 	defer buffer.Release()
 
@@ -60,8 +59,7 @@ func EncodeRequestHeader(writer io.Writer, request *protocol.RequestHeader, requ
 }
 
 // DecodeRequestHeader decodes and returns (if successful) a RequestHeader from an input stream.
-func DecodeRequestHeader(isfb bool, first *buf.Buffer, reader io.Reader, validator *vless.Validator) (*protocol.RequestHeader, *Addons, error, bool) {
-
+func DecodeRequestHeader(isfb bool, first *buf.Buffer, reader io.Reader, validator *vless.Validator) (*protocol.RequestHeader, *Addons, bool, error) {
 	buffer := buf.StackNew()
 	defer buffer.Release()
 
@@ -71,7 +69,7 @@ func DecodeRequestHeader(isfb bool, first *buf.Buffer, reader io.Reader, validat
 		request.Version = first.Byte(0)
 	} else {
 		if _, err := buffer.ReadFullFrom(reader, 1); err != nil {
-			return nil, nil, newError("failed to read request version").Base(err), false
+			return nil, nil, false, newError("failed to read request version").Base(err)
 		}
 		request.Version = buffer.Byte(0)
 	}
@@ -86,13 +84,13 @@ func DecodeRequestHeader(isfb bool, first *buf.Buffer, reader io.Reader, validat
 		} else {
 			buffer.Clear()
 			if _, err := buffer.ReadFullFrom(reader, 16); err != nil {
-				return nil, nil, newError("failed to read request user id").Base(err), false
+				return nil, nil, false, newError("failed to read request user id").Base(err)
 			}
 			copy(id[:], buffer.Bytes())
 		}
 
 		if request.User = validator.Get(id); request.User == nil {
-			return nil, nil, newError("invalid request user id"), isfb
+			return nil, nil, isfb, newError("invalid request user id")
 		}
 
 		if isfb {
@@ -101,12 +99,12 @@ func DecodeRequestHeader(isfb bool, first *buf.Buffer, reader io.Reader, validat
 
 		requestAddons, err := DecodeHeaderAddons(&buffer, reader)
 		if err != nil {
-			return nil, nil, newError("failed to decode request header addons").Base(err), false
+			return nil, nil, false, newError("failed to decode request header addons").Base(err)
 		}
 
 		buffer.Clear()
 		if _, err := buffer.ReadFullFrom(reader, 1); err != nil {
-			return nil, nil, newError("failed to read request command").Base(err), false
+			return nil, nil, false, newError("failed to read request command").Base(err)
 		}
 
 		request.Command = protocol.RequestCommand(buffer.Byte(0))
@@ -120,24 +118,17 @@ func DecodeRequestHeader(isfb bool, first *buf.Buffer, reader io.Reader, validat
 				request.Port = port
 			}
 		}
-
 		if request.Address == nil {
-			return nil, nil, newError("invalid request address"), false
+			return nil, nil, false, newError("invalid request address")
 		}
-
-		return request, requestAddons, nil, false
-
+		return request, requestAddons, false, nil
 	default:
-
-		return nil, nil, newError("invalid request version"), isfb
-
+		return nil, nil, isfb, newError("invalid request version")
 	}
-
 }
 
 // EncodeResponseHeader writes encoded response header into the given writer.
 func EncodeResponseHeader(writer io.Writer, request *protocol.RequestHeader, responseAddons *Addons) error {
-
 	buffer := buf.StackNew()
 	defer buffer.Release()
 
@@ -158,7 +149,6 @@ func EncodeResponseHeader(writer io.Writer, request *protocol.RequestHeader, res
 
 // DecodeResponseHeader decodes and returns (if successful) a ResponseHeader from an input stream.
 func DecodeResponseHeader(reader io.Reader, request *protocol.RequestHeader) (*Addons, error) {
-
 	buffer := buf.StackNew()
 	defer buffer.Release()
 
diff --git a/proxy/vless/encoding/encoding_test.go b/proxy/vless/encoding/encoding_test.go
index 12c9e2b57..5366b84d2 100644
--- a/proxy/vless/encoding/encoding_test.go
+++ b/proxy/vless/encoding/encoding_test.go
@@ -46,7 +46,7 @@ func TestRequestSerialization(t *testing.T) {
 	Validator := new(vless.Validator)
 	Validator.Add(user)
 
-	actualRequest, actualAddons, err, _ := DecodeRequestHeader(false, nil, &buffer, Validator)
+	actualRequest, actualAddons, _, err := DecodeRequestHeader(false, nil, &buffer, Validator)
 	common.Must(err)
 
 	if r := cmp.Diff(actualRequest, expectedRequest, cmp.AllowUnexported(protocol.ID{})); r != "" {
@@ -83,7 +83,7 @@ func TestInvalidRequest(t *testing.T) {
 	Validator := new(vless.Validator)
 	Validator.Add(user)
 
-	_, _, err, _ := DecodeRequestHeader(false, nil, &buffer, Validator)
+	_, _, _, err := DecodeRequestHeader(false, nil, &buffer, Validator)
 	if err == nil {
 		t.Error("nil error")
 	}
@@ -114,7 +114,7 @@ func TestMuxRequest(t *testing.T) {
 	Validator := new(vless.Validator)
 	Validator.Add(user)
 
-	actualRequest, actualAddons, err, _ := DecodeRequestHeader(false, nil, &buffer, Validator)
+	actualRequest, actualAddons, _, err := DecodeRequestHeader(false, nil, &buffer, Validator)
 	common.Must(err)
 
 	if r := cmp.Diff(actualRequest, expectedRequest, cmp.AllowUnexported(protocol.ID{})); r != "" {
diff --git a/proxy/vless/inbound/inbound.go b/proxy/vless/inbound/inbound.go
index db5a599f2..b2e736d49 100644
--- a/proxy/vless/inbound/inbound.go
+++ b/proxy/vless/inbound/inbound.go
@@ -64,12 +64,11 @@ type Handler struct {
 	validator             *vless.Validator
 	dns                   dns.Client
 	fallbacks             map[string]map[string]*Fallback // or nil
-	//regexps               map[string]*regexp.Regexp       // or nil
+	// regexps               map[string]*regexp.Regexp       // or nil
 }
 
 // New creates a new VLess inbound handler.
 func New(ctx context.Context, config *Config, dc dns.Client) (*Handler, error) {
-
 	v := core.MustFromContext(ctx)
 	handler := &Handler{
 		inboundHandlerManager: v.GetFeature(feature_inbound.ManagerType()).(feature_inbound.Manager),
@@ -90,7 +89,7 @@ func New(ctx context.Context, config *Config, dc dns.Client) (*Handler, error) {
 
 	if config.Fallbacks != nil {
 		handler.fallbacks = make(map[string]map[string]*Fallback)
-		//handler.regexps = make(map[string]*regexp.Regexp)
+		// handler.regexps = make(map[string]*regexp.Regexp)
 		for _, fb := range config.Fallbacks {
 			if handler.fallbacks[fb.Alpn] == nil {
 				handler.fallbacks[fb.Alpn] = make(map[string]*Fallback)
@@ -144,9 +143,7 @@ func (*Handler) Network() []net.Network {
 
 // Process implements proxy.Inbound.Process().
 func (h *Handler) Process(ctx context.Context, network net.Network, connection internet.Connection, dispatcher routing.Dispatcher) error {
-
 	sid := session.ExportIDToError(ctx)
-
 	iConn := connection
 	if statConn, ok := iConn.(*internet.StatCouterConnection); ok {
 		iConn = statConn.Connection
@@ -178,11 +175,10 @@ func (h *Handler) Process(ctx context.Context, network net.Network, connection i
 	if isfb && firstLen < 18 {
 		err = newError("fallback directly")
 	} else {
-		request, requestAddons, err, isfb = encoding.DecodeRequestHeader(isfb, first, reader, h.validator)
+		request, requestAddons, isfb, err = encoding.DecodeRequestHeader(isfb, first, reader, h.validator)
 	}
 
 	if err != nil {
-
 		if isfb {
 			if err := connection.SetReadDeadline(time.Time{}); err != nil {
 				newError("unable to set back read deadline").Base(err).AtWarning().WriteToLog(sid)
@@ -271,7 +267,7 @@ func (h *Handler) Process(ctx context.Context, network net.Network, connection i
 			}); err != nil {
 				return newError("failed to dial to " + fb.Dest).Base(err).AtWarning()
 			}
-			defer conn.Close() // nolint: errcheck
+			defer conn.Close()
 
 			serverReader := buf.NewReader(conn)
 			serverWriter := buf.NewWriter(conn)
@@ -303,6 +299,7 @@ func (h *Handler) Process(ctx context.Context, network net.Network, connection i
 						} else {
 							pro.Write([]byte("PROXY TCP6 " + remoteAddr + " " + localAddr + " " + remotePort + " " + localPort + "\r\n"))
 						}
+
 					case 2:
 						pro.Write([]byte("\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A\x21")) // signature + v2 + PROXY
 						if ipv4 {
@@ -372,7 +369,7 @@ func (h *Handler) Process(ctx context.Context, network net.Network, connection i
 	account := request.User.Account.(*vless.MemoryAccount)
 
 	responseAddons := &encoding.Addons{
-		//Flow: requestAddons.Flow,
+		// Flow: requestAddons.Flow,
 	}
 
 	switch requestAddons.Flow {
@@ -473,7 +470,6 @@ func (h *Handler) Process(ctx context.Context, network net.Network, connection i
 		// Indicates the end of response payload.
 		switch responseAddons.Flow {
 		default:
-
 		}
 
 		return nil
diff --git a/proxy/vless/outbound/outbound.go b/proxy/vless/outbound/outbound.go
index b7d7d65df..d052ef2ad 100644
--- a/proxy/vless/outbound/outbound.go
+++ b/proxy/vless/outbound/outbound.go
@@ -52,7 +52,6 @@ type Handler struct {
 
 // New creates a new VLess outbound handler.
 func New(ctx context.Context, config *Config) (*Handler, error) {
-
 	serverList := protocol.NewServerList()
 	for _, rec := range config.Vnext {
 		s, err := protocol.NewServerSpecFromPB(rec)
@@ -74,7 +73,6 @@ func New(ctx context.Context, config *Config) (*Handler, error) {
 
 // Process implements proxy.Outbound.Process().
 func (h *Handler) Process(ctx context.Context, link *transport.Link, dialer internet.Dialer) error {
-
 	var rec *protocol.ServerSpec
 	var conn internet.Connection
 
@@ -89,7 +87,7 @@ func (h *Handler) Process(ctx context.Context, link *transport.Link, dialer inte
 	}); err != nil {
 		return newError("failed to find an available destination").Base(err).AtWarning()
 	}
-	defer conn.Close() // nolint: errcheck
+	defer conn.Close()
 
 	iConn := conn
 	if statConn, ok := iConn.(*internet.StatCouterConnection); ok {
@@ -193,9 +191,7 @@ func (h *Handler) Process(ctx context.Context, link *transport.Link, dialer inte
 		// Indicates the end of request payload.
 		switch requestAddons.Flow {
 		default:
-
 		}
-
 		return nil
 	}
 
diff --git a/proxy/vmess/aead/authid.go b/proxy/vmess/aead/authid.go
index 5ba2db1fa..adde14a75 100644
--- a/proxy/vmess/aead/authid.go
+++ b/proxy/vmess/aead/authid.go
@@ -11,10 +11,16 @@ import (
 	"io"
 	"math"
 	"time"
+
 	"v2ray.com/core/common"
 	antiReplayWindow "v2ray.com/core/common/antireplay"
 )
 
+var (
+	ErrNotFound = errors.New("user do not exist")
+	ErrReplay   = errors.New("replayed request")
+)
+
 func CreateAuthID(cmdKey []byte, time int64) [16]byte {
 	buf := bytes.NewBuffer(nil)
 	common.Must(binary.Write(buf, binary.BigEndian, time))
@@ -32,7 +38,7 @@ func CreateAuthID(cmdKey []byte, time int64) [16]byte {
 }
 
 func NewCipherFromKey(cmdKey []byte) cipher.Block {
-	aesBlock, err := aes.NewCipher(KDF16(cmdKey, KDFSaltConst_AuthIDEncryptionKey))
+	aesBlock, err := aes.NewCipher(KDF16(cmdKey, KDFSaltConstAuthIDEncryptionKey))
 	if err != nil {
 		panic(err)
 	}
@@ -88,10 +94,9 @@ func (a *AuthIDDecoderHolder) RemoveUser(key [16]byte) {
 	delete(a.aidhi, string(key[:]))
 }
 
-func (a *AuthIDDecoderHolder) Match(AuthID [16]byte) (interface{}, error) {
+func (a *AuthIDDecoderHolder) Match(authID [16]byte) (interface{}, error) {
 	for _, v := range a.aidhi {
-
-		t, z, r, d := v.dec.Decode(AuthID)
+		t, z, r, d := v.dec.Decode(authID)
 		if z != crc32.ChecksumIEEE(d[:12]) {
 			continue
 		}
@@ -104,18 +109,13 @@ func (a *AuthIDDecoderHolder) Match(AuthID [16]byte) (interface{}, error) {
 			continue
 		}
 
-		if !a.apw.Check(AuthID[:]) {
+		if !a.apw.Check(authID[:]) {
 			return nil, ErrReplay
 		}
 
 		_ = r
 
 		return v.ticket, nil
-
 	}
 	return nil, ErrNotFound
 }
-
-var ErrNotFound = errors.New("user do not exist")
-
-var ErrReplay = errors.New("replayed request")
diff --git a/proxy/vmess/aead/authid_test.go b/proxy/vmess/aead/authid_test.go
index c1f923c53..837d3372b 100644
--- a/proxy/vmess/aead/authid_test.go
+++ b/proxy/vmess/aead/authid_test.go
@@ -2,10 +2,11 @@ package aead
 
 import (
 	"fmt"
-	"github.com/stretchr/testify/assert"
 	"strconv"
 	"testing"
 	"time"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestCreateAuthID(t *testing.T) {
@@ -57,7 +58,6 @@ func TestCreateAuthIDAndDecode2(t *testing.T) {
 	res2, err2 := AuthDecoder.Match(authid2)
 	assert.EqualError(t, err2, "user do not exist")
 	assert.Nil(t, res2)
-
 }
 
 func TestCreateAuthIDAndDecodeMassive(t *testing.T) {
@@ -89,7 +89,6 @@ func TestCreateAuthIDAndDecodeMassive(t *testing.T) {
 	res2, err2 := AuthDecoder.Match(authid3)
 	assert.Equal(t, "Demo User", res2)
 	assert.Nil(t, err2)
-
 }
 
 func TestCreateAuthIDAndDecodeSuperMassive(t *testing.T) {
@@ -125,5 +124,4 @@ func TestCreateAuthIDAndDecodeSuperMassive(t *testing.T) {
 	assert.Nil(t, err2)
 
 	fmt.Println(after.Sub(before).Seconds())
-
 }
diff --git a/proxy/vmess/aead/consts.go b/proxy/vmess/aead/consts.go
index 7a62fc53b..ef13977db 100644
--- a/proxy/vmess/aead/consts.go
+++ b/proxy/vmess/aead/consts.go
@@ -1,21 +1,14 @@
 package aead
 
-const KDFSaltConst_AuthIDEncryptionKey = "AES Auth ID Encryption"
-
-const KDFSaltConst_AEADRespHeaderLenKey = "AEAD Resp Header Len Key"
-
-const KDFSaltConst_AEADRespHeaderLenIV = "AEAD Resp Header Len IV"
-
-const KDFSaltConst_AEADRespHeaderPayloadKey = "AEAD Resp Header Key"
-
-const KDFSaltConst_AEADRespHeaderPayloadIV = "AEAD Resp Header IV"
-
-const KDFSaltConst_VMessAEADKDF = "VMess AEAD KDF"
-
-const KDFSaltConst_VMessHeaderPayloadAEADKey = "VMess Header AEAD Key"
-
-const KDFSaltConst_VMessHeaderPayloadAEADIV = "VMess Header AEAD Nonce"
-
-const KDFSaltConst_VMessHeaderPayloadLengthAEADKey = "VMess Header AEAD Key_Length"
-
-const KDFSaltConst_VMessHeaderPayloadLengthAEADIV = "VMess Header AEAD Nonce_Length"
+const (
+	KDFSaltConstAuthIDEncryptionKey             = "AES Auth ID Encryption"
+	KDFSaltConstAEADRespHeaderLenKey            = "AEAD Resp Header Len Key"
+	KDFSaltConstAEADRespHeaderLenIV             = "AEAD Resp Header Len IV"
+	KDFSaltConstAEADRespHeaderPayloadKey        = "AEAD Resp Header Key"
+	KDFSaltConstAEADRespHeaderPayloadIV         = "AEAD Resp Header IV"
+	KDFSaltConstVMessAEADKDF                    = "VMess AEAD KDF"
+	KDFSaltConstVMessHeaderPayloadAEADKey       = "VMess Header AEAD Key"
+	KDFSaltConstVMessHeaderPayloadAEADIV        = "VMess Header AEAD Nonce"
+	KDFSaltConstVMessHeaderPayloadLengthAEADKey = "VMess Header AEAD Key_Length"
+	KDFSaltConstVMessHeaderPayloadLengthAEADIV  = "VMess Header AEAD Nonce_Length"
+)
diff --git a/proxy/vmess/aead/encrypt.go b/proxy/vmess/aead/encrypt.go
index d2d0b1dea..073a4ac2e 100644
--- a/proxy/vmess/aead/encrypt.go
+++ b/proxy/vmess/aead/encrypt.go
@@ -30,9 +30,9 @@ func SealVMessAEADHeader(key [16]byte, data []byte) []byte {
 	var payloadHeaderLengthAEADEncrypted []byte
 
 	{
-		payloadHeaderLengthAEADKey := KDF16(key[:], KDFSaltConst_VMessHeaderPayloadLengthAEADKey, string(generatedAuthID[:]), string(connectionNonce))
+		payloadHeaderLengthAEADKey := KDF16(key[:], KDFSaltConstVMessHeaderPayloadLengthAEADKey, string(generatedAuthID[:]), string(connectionNonce))
 
-		payloadHeaderLengthAEADNonce := KDF(key[:], KDFSaltConst_VMessHeaderPayloadLengthAEADIV, string(generatedAuthID[:]), string(connectionNonce))[:12]
+		payloadHeaderLengthAEADNonce := KDF(key[:], KDFSaltConstVMessHeaderPayloadLengthAEADIV, string(generatedAuthID[:]), string(connectionNonce))[:12]
 
 		payloadHeaderLengthAEADAESBlock, err := aes.NewCipher(payloadHeaderLengthAEADKey)
 		if err != nil {
@@ -51,9 +51,9 @@ func SealVMessAEADHeader(key [16]byte, data []byte) []byte {
 	var payloadHeaderAEADEncrypted []byte
 
 	{
-		payloadHeaderAEADKey := KDF16(key[:], KDFSaltConst_VMessHeaderPayloadAEADKey, string(generatedAuthID[:]), string(connectionNonce))
+		payloadHeaderAEADKey := KDF16(key[:], KDFSaltConstVMessHeaderPayloadAEADKey, string(generatedAuthID[:]), string(connectionNonce))
 
-		payloadHeaderAEADNonce := KDF(key[:], KDFSaltConst_VMessHeaderPayloadAEADIV, string(generatedAuthID[:]), string(connectionNonce))[:12]
+		payloadHeaderAEADNonce := KDF(key[:], KDFSaltConstVMessHeaderPayloadAEADIV, string(generatedAuthID[:]), string(connectionNonce))[:12]
 
 		payloadHeaderAEADAESBlock, err := aes.NewCipher(payloadHeaderAEADKey)
 		if err != nil {
@@ -71,18 +71,15 @@ func SealVMessAEADHeader(key [16]byte, data []byte) []byte {
 
 	var outputBuffer = bytes.NewBuffer(nil)
 
-	common.Must2(outputBuffer.Write(generatedAuthID[:])) //16
-
-	common.Must2(outputBuffer.Write(payloadHeaderLengthAEADEncrypted)) //2+16
-
-	common.Must2(outputBuffer.Write(connectionNonce)) //8
-
+	common.Must2(outputBuffer.Write(generatedAuthID[:]))               // 16
+	common.Must2(outputBuffer.Write(payloadHeaderLengthAEADEncrypted)) // 2+16
+	common.Must2(outputBuffer.Write(connectionNonce))                  // 8
 	common.Must2(outputBuffer.Write(payloadHeaderAEADEncrypted))
 
 	return outputBuffer.Bytes()
 }
 
-func OpenVMessAEADHeader(key [16]byte, authid [16]byte, data io.Reader) ([]byte, bool, error, int) {
+func OpenVMessAEADHeader(key [16]byte, authid [16]byte, data io.Reader) ([]byte, bool, int, error) {
 	var payloadHeaderLengthAEADEncrypted [18]byte
 	var nonce [8]byte
 
@@ -91,23 +88,23 @@ func OpenVMessAEADHeader(key [16]byte, authid [16]byte, data io.Reader) ([]byte,
 	authidCheckValueReadBytesCounts, err := io.ReadFull(data, payloadHeaderLengthAEADEncrypted[:])
 	bytesRead += authidCheckValueReadBytesCounts
 	if err != nil {
-		return nil, false, err, bytesRead
+		return nil, false, bytesRead, err
 	}
 
 	nonceReadBytesCounts, err := io.ReadFull(data, nonce[:])
 	bytesRead += nonceReadBytesCounts
 	if err != nil {
-		return nil, false, err, bytesRead
+		return nil, false, bytesRead, err
 	}
 
-	//Decrypt Length
+	// Decrypt Length
 
 	var decryptedAEADHeaderLengthPayloadResult []byte
 
 	{
-		payloadHeaderLengthAEADKey := KDF16(key[:], KDFSaltConst_VMessHeaderPayloadLengthAEADKey, string(authid[:]), string(nonce[:]))
+		payloadHeaderLengthAEADKey := KDF16(key[:], KDFSaltConstVMessHeaderPayloadLengthAEADKey, string(authid[:]), string(nonce[:]))
 
-		payloadHeaderLengthAEADNonce := KDF(key[:], KDFSaltConst_VMessHeaderPayloadLengthAEADIV, string(authid[:]), string(nonce[:]))[:12]
+		payloadHeaderLengthAEADNonce := KDF(key[:], KDFSaltConstVMessHeaderPayloadLengthAEADIV, string(authid[:]), string(nonce[:]))[:12]
 
 		payloadHeaderAEADAESBlock, err := aes.NewCipher(payloadHeaderLengthAEADKey)
 		if err != nil {
@@ -123,7 +120,7 @@ func OpenVMessAEADHeader(key [16]byte, authid [16]byte, data io.Reader) ([]byte,
 		decryptedAEADHeaderLengthPayload, erropenAEAD := payloadHeaderLengthAEAD.Open(nil, payloadHeaderLengthAEADNonce, payloadHeaderLengthAEADEncrypted[:], authid[:])
 
 		if erropenAEAD != nil {
-			return nil, true, erropenAEAD, bytesRead
+			return nil, true, bytesRead, erropenAEAD
 		}
 
 		decryptedAEADHeaderLengthPayloadResult = decryptedAEADHeaderLengthPayload
@@ -131,24 +128,24 @@ func OpenVMessAEADHeader(key [16]byte, authid [16]byte, data io.Reader) ([]byte,
 
 	var length uint16
 
-	common.Must(binary.Read(bytes.NewReader(decryptedAEADHeaderLengthPayloadResult[:]), binary.BigEndian, &length))
+	common.Must(binary.Read(bytes.NewReader(decryptedAEADHeaderLengthPayloadResult), binary.BigEndian, &length))
 
 	var decryptedAEADHeaderPayloadR []byte
 
 	var payloadHeaderAEADEncryptedReadedBytesCounts int
 
 	{
-		payloadHeaderAEADKey := KDF16(key[:], KDFSaltConst_VMessHeaderPayloadAEADKey, string(authid[:]), string(nonce[:]))
+		payloadHeaderAEADKey := KDF16(key[:], KDFSaltConstVMessHeaderPayloadAEADKey, string(authid[:]), string(nonce[:]))
 
-		payloadHeaderAEADNonce := KDF(key[:], KDFSaltConst_VMessHeaderPayloadAEADIV, string(authid[:]), string(nonce[:]))[:12]
+		payloadHeaderAEADNonce := KDF(key[:], KDFSaltConstVMessHeaderPayloadAEADIV, string(authid[:]), string(nonce[:]))[:12]
 
-		//16 == AEAD Tag size
+		// 16 == AEAD Tag size
 		payloadHeaderAEADEncrypted := make([]byte, length+16)
 
 		payloadHeaderAEADEncryptedReadedBytesCounts, err = io.ReadFull(data, payloadHeaderAEADEncrypted)
 		bytesRead += payloadHeaderAEADEncryptedReadedBytesCounts
 		if err != nil {
-			return nil, false, err, bytesRead
+			return nil, false, bytesRead, err
 		}
 
 		payloadHeaderAEADAESBlock, err := aes.NewCipher(payloadHeaderAEADKey)
@@ -165,11 +162,11 @@ func OpenVMessAEADHeader(key [16]byte, authid [16]byte, data io.Reader) ([]byte,
 		decryptedAEADHeaderPayload, erropenAEAD := payloadHeaderAEAD.Open(nil, payloadHeaderAEADNonce, payloadHeaderAEADEncrypted, authid[:])
 
 		if erropenAEAD != nil {
-			return nil, true, erropenAEAD, bytesRead
+			return nil, true, bytesRead, erropenAEAD
 		}
 
 		decryptedAEADHeaderPayloadR = decryptedAEADHeaderPayload
 	}
 
-	return decryptedAEADHeaderPayloadR, false, nil, bytesRead
+	return decryptedAEADHeaderPayloadR, false, bytesRead, nil
 }
diff --git a/proxy/vmess/aead/encrypt_test.go b/proxy/vmess/aead/encrypt_test.go
index 9e5f7af94..b18cfcce2 100644
--- a/proxy/vmess/aead/encrypt_test.go
+++ b/proxy/vmess/aead/encrypt_test.go
@@ -22,7 +22,7 @@ func TestOpenVMessAEADHeader(t *testing.T) {
 
 	io.ReadFull(AEADR, authid[:])
 
-	out, _, err, _ := OpenVMessAEADHeader(keyw, authid, AEADR)
+	out, _, _, err := OpenVMessAEADHeader(keyw, authid, AEADR)
 
 	fmt.Println(string(out))
 	fmt.Println(err)
@@ -41,7 +41,7 @@ func TestOpenVMessAEADHeader2(t *testing.T) {
 
 	io.ReadFull(AEADR, authid[:])
 
-	out, _, err, readen := OpenVMessAEADHeader(keyw, authid, AEADR)
+	out, _, readen, err := OpenVMessAEADHeader(keyw, authid, AEADR)
 	assert.Equal(t, len(sealed)-16-AEADR.Len(), readen)
 	assert.Equal(t, string(TestHeader), string(out))
 	assert.Nil(t, err)
@@ -63,7 +63,7 @@ func TestOpenVMessAEADHeader4(t *testing.T) {
 
 		io.ReadFull(AEADR, authid[:])
 
-		out, drain, err, readen := OpenVMessAEADHeader(keyw, authid, AEADR)
+		out, drain, readen, err := OpenVMessAEADHeader(keyw, authid, AEADR)
 		assert.Equal(t, len(sealed)-16-AEADR.Len(), readen)
 		assert.Equal(t, true, drain)
 		assert.NotNil(t, err)
@@ -72,12 +72,10 @@ func TestOpenVMessAEADHeader4(t *testing.T) {
 		}
 		assert.Nil(t, out)
 	}
-
 }
 
 func TestOpenVMessAEADHeader4Massive(t *testing.T) {
 	for j := 0; j < 1000; j++ {
-
 		for i := 0; i <= 60; i++ {
 			TestHeader := []byte("Test Header")
 			key := KDF16([]byte("Demo Key for Auth ID Test"), "Demo Path for Auth ID Test")
@@ -93,7 +91,7 @@ func TestOpenVMessAEADHeader4Massive(t *testing.T) {
 
 			io.ReadFull(AEADR, authid[:])
 
-			out, drain, err, readen := OpenVMessAEADHeader(keyw, authid, AEADR)
+			out, drain, readen, err := OpenVMessAEADHeader(keyw, authid, AEADR)
 			assert.Equal(t, len(sealed)-16-AEADR.Len(), readen)
 			assert.Equal(t, true, drain)
 			assert.NotNil(t, err)
diff --git a/proxy/vmess/aead/kdf.go b/proxy/vmess/aead/kdf.go
index 26b9540c3..ebcea0a30 100644
--- a/proxy/vmess/aead/kdf.go
+++ b/proxy/vmess/aead/kdf.go
@@ -7,9 +7,7 @@ import (
 )
 
 func KDF(key []byte, path ...string) []byte {
-	hmacf := hmac.New(func() hash.Hash {
-		return sha256.New()
-	}, []byte(KDFSaltConst_VMessAEADKDF))
+	hmacf := hmac.New(sha256.New, []byte(KDFSaltConstVMessAEADKDF))
 
 	for _, v := range path {
 		hmacf = hmac.New(func() hash.Hash {
diff --git a/proxy/vmess/encoding/client.go b/proxy/vmess/encoding/client.go
index 78945532d..564ba51e0 100644
--- a/proxy/vmess/encoding/client.go
+++ b/proxy/vmess/encoding/client.go
@@ -47,8 +47,7 @@ type ClientSession struct {
 }
 
 // NewClientSession creates a new ClientSession.
-func NewClientSession(isAEAD bool, idHash protocol.IDHash, ctx context.Context) *ClientSession {
-
+func NewClientSession(ctx context.Context, isAEAD bool, idHash protocol.IDHash) *ClientSession {
 	session := &ClientSession{
 		isAEAD: isAEAD,
 		idHash: idHash,
@@ -114,7 +113,7 @@ func (c *ClientSession) EncodeRequestHeader(header *protocol.RequestHeader, writ
 
 	if !c.isAEAD {
 		iv := hashTimestamp(md5.New(), timestamp)
-		aesStream := crypto.NewAesEncryptionStream(account.ID.CmdKey(), iv[:])
+		aesStream := crypto.NewAesEncryptionStream(account.ID.CmdKey(), iv)
 		aesStream.XORKeyStream(buffer.Bytes(), buffer.Bytes())
 		common.Must2(writer.Write(buffer.Bytes()))
 	} else {
@@ -193,8 +192,8 @@ func (c *ClientSession) DecodeResponseHeader(reader io.Reader) (*protocol.Respon
 		aesStream := crypto.NewAesDecryptionStream(c.responseBodyKey[:], c.responseBodyIV[:])
 		c.responseReader = crypto.NewCryptionReader(aesStream, reader)
 	} else {
-		aeadResponseHeaderLengthEncryptionKey := vmessaead.KDF16(c.responseBodyKey[:], vmessaead.KDFSaltConst_AEADRespHeaderLenKey)
-		aeadResponseHeaderLengthEncryptionIV := vmessaead.KDF(c.responseBodyIV[:], vmessaead.KDFSaltConst_AEADRespHeaderLenIV)[:12]
+		aeadResponseHeaderLengthEncryptionKey := vmessaead.KDF16(c.responseBodyKey[:], vmessaead.KDFSaltConstAEADRespHeaderLenKey)
+		aeadResponseHeaderLengthEncryptionIV := vmessaead.KDF(c.responseBodyIV[:], vmessaead.KDFSaltConstAEADRespHeaderLenIV)[:12]
 
 		aeadResponseHeaderLengthEncryptionKeyAESBlock := common.Must2(aes.NewCipher(aeadResponseHeaderLengthEncryptionKey)).(cipher.Block)
 		aeadResponseHeaderLengthEncryptionAEAD := common.Must2(cipher.NewGCM(aeadResponseHeaderLengthEncryptionKeyAESBlock)).(cipher.AEAD)
@@ -213,8 +212,8 @@ func (c *ClientSession) DecodeResponseHeader(reader io.Reader) (*protocol.Respon
 			decryptedResponseHeaderLength = int(decryptedResponseHeaderLengthBinaryDeserializeBuffer)
 		}
 
-		aeadResponseHeaderPayloadEncryptionKey := vmessaead.KDF16(c.responseBodyKey[:], vmessaead.KDFSaltConst_AEADRespHeaderPayloadKey)
-		aeadResponseHeaderPayloadEncryptionIV := vmessaead.KDF(c.responseBodyIV[:], vmessaead.KDFSaltConst_AEADRespHeaderPayloadIV)[:12]
+		aeadResponseHeaderPayloadEncryptionKey := vmessaead.KDF16(c.responseBodyKey[:], vmessaead.KDFSaltConstAEADRespHeaderPayloadKey)
+		aeadResponseHeaderPayloadEncryptionIV := vmessaead.KDF(c.responseBodyIV[:], vmessaead.KDFSaltConstAEADRespHeaderPayloadIV)[:12]
 
 		aeadResponseHeaderPayloadEncryptionKeyAESBlock := common.Must2(aes.NewCipher(aeadResponseHeaderPayloadEncryptionKey)).(cipher.Block)
 		aeadResponseHeaderPayloadEncryptionAEAD := common.Must2(cipher.NewGCM(aeadResponseHeaderPayloadEncryptionKeyAESBlock)).(cipher.AEAD)
diff --git a/proxy/vmess/encoding/encoding_test.go b/proxy/vmess/encoding/encoding_test.go
index c0f938b7d..5abcee9dc 100644
--- a/proxy/vmess/encoding/encoding_test.go
+++ b/proxy/vmess/encoding/encoding_test.go
@@ -43,7 +43,7 @@ func TestRequestSerialization(t *testing.T) {
 	}
 
 	buffer := buf.New()
-	client := NewClientSession(true, protocol.DefaultIDHash, context.TODO())
+	client := NewClientSession(context.TODO(), true, protocol.DefaultIDHash)
 	common.Must(client.EncodeRequestHeader(expectedRequest, buffer))
 
 	buffer2 := buf.New()
@@ -93,7 +93,7 @@ func TestInvalidRequest(t *testing.T) {
 	}
 
 	buffer := buf.New()
-	client := NewClientSession(true, protocol.DefaultIDHash, context.TODO())
+	client := NewClientSession(context.TODO(), true, protocol.DefaultIDHash)
 	common.Must(client.EncodeRequestHeader(expectedRequest, buffer))
 
 	buffer2 := buf.New()
@@ -134,7 +134,7 @@ func TestMuxRequest(t *testing.T) {
 	}
 
 	buffer := buf.New()
-	client := NewClientSession(true, protocol.DefaultIDHash, context.TODO())
+	client := NewClientSession(context.TODO(), true, protocol.DefaultIDHash)
 	common.Must(client.EncodeRequestHeader(expectedRequest, buffer))
 
 	buffer2 := buf.New()
diff --git a/proxy/vmess/encoding/server.go b/proxy/vmess/encoding/server.go
index 680f35ef9..6dbc2d696 100644
--- a/proxy/vmess/encoding/server.go
+++ b/proxy/vmess/encoding/server.go
@@ -26,7 +26,7 @@ import (
 	vmessaead "v2ray.com/core/proxy/vmess/aead"
 )
 
-type sessionId struct {
+type sessionID struct {
 	user  [16]byte
 	key   [16]byte
 	nonce [16]byte
@@ -35,14 +35,14 @@ type sessionId struct {
 // SessionHistory keeps track of historical session ids, to prevent replay attacks.
 type SessionHistory struct {
 	sync.RWMutex
-	cache map[sessionId]time.Time
+	cache map[sessionID]time.Time
 	task  *task.Periodic
 }
 
 // NewSessionHistory creates a new SessionHistory object.
 func NewSessionHistory() *SessionHistory {
 	h := &SessionHistory{
-		cache: make(map[sessionId]time.Time, 128),
+		cache: make(map[sessionID]time.Time, 128),
 	}
 	h.task = &task.Periodic{
 		Interval: time.Second * 30,
@@ -56,7 +56,7 @@ func (h *SessionHistory) Close() error {
 	return h.task.Close()
 }
 
-func (h *SessionHistory) addIfNotExits(session sessionId) bool {
+func (h *SessionHistory) addIfNotExits(session sessionID) bool {
 	h.Lock()
 
 	if expire, found := h.cache[session]; found && expire.After(time.Now()) {
@@ -87,7 +87,7 @@ func (h *SessionHistory) removeExpiredEntries() error {
 	}
 
 	if len(h.cache) == 0 {
-		h.cache = make(map[sessionId]time.Time, 128)
+		h.cache = make(map[sessionID]time.Time, 128)
 	}
 
 	return nil
@@ -141,7 +141,7 @@ func (s *ServerSession) DecodeRequestHeader(reader io.Reader) (*protocol.Request
 	readSizeRemain := DrainSize
 
 	drainConnection := func(e error) error {
-		//We read a deterministic generated length of data before closing the connection to offset padding read pattern
+		// We read a deterministic generated length of data before closing the connection to offset padding read pattern
 		readSizeRemain -= int(buffer.Len())
 		if readSizeRemain > 0 {
 			err := s.DrainConnN(reader, readSizeRemain)
@@ -169,22 +169,24 @@ func (s *ServerSession) DecodeRequestHeader(reader io.Reader) (*protocol.Request
 	var fixedSizeAuthID [16]byte
 	copy(fixedSizeAuthID[:], buffer.Bytes())
 
-	if foundAEAD {
+	switch {
+	case foundAEAD:
 		vmessAccount = user.Account.(*vmess.MemoryAccount)
 		var fixedSizeCmdKey [16]byte
 		copy(fixedSizeCmdKey[:], vmessAccount.ID.CmdKey())
-		aeadData, shouldDrain, errorReason, bytesRead := vmessaead.OpenVMessAEADHeader(fixedSizeCmdKey, fixedSizeAuthID, reader)
+		aeadData, shouldDrain, bytesRead, errorReason := vmessaead.OpenVMessAEADHeader(fixedSizeCmdKey, fixedSizeAuthID, reader)
 		if errorReason != nil {
 			if shouldDrain {
 				readSizeRemain -= bytesRead
 				return nil, drainConnection(newError("AEAD read failed").Base(errorReason))
 			} else {
-				return nil, drainConnection(newError("AEAD read failed, drain skiped").Base(errorReason))
+				return nil, drainConnection(newError("AEAD read failed, drain skipped").Base(errorReason))
 			}
 		}
 		decryptor = bytes.NewReader(aeadData)
 		s.isAEADRequest = true
-	} else if !s.isAEADForced && errorAEAD == vmessaead.ErrNotFound {
+
+	case !s.isAEADForced && errorAEAD == vmessaead.ErrNotFound:
 		userLegacy, timestamp, valid, userValidationError := s.userValidator.Get(buffer.Bytes())
 		if !valid || userValidationError != nil {
 			return nil, drainConnection(newError("invalid user").Base(userValidationError))
@@ -193,9 +195,10 @@ func (s *ServerSession) DecodeRequestHeader(reader io.Reader) (*protocol.Request
 		iv := hashTimestamp(md5.New(), timestamp)
 		vmessAccount = userLegacy.Account.(*vmess.MemoryAccount)
 
-		aesStream := crypto.NewAesDecryptionStream(vmessAccount.ID.CmdKey(), iv[:])
+		aesStream := crypto.NewAesDecryptionStream(vmessAccount.ID.CmdKey(), iv)
 		decryptor = crypto.NewCryptionReader(aesStream, reader)
-	} else {
+
+	default:
 		return nil, drainConnection(newError("invalid user").Base(errorAEAD))
 	}
 
@@ -212,7 +215,7 @@ func (s *ServerSession) DecodeRequestHeader(reader io.Reader) (*protocol.Request
 
 	copy(s.requestBodyIV[:], buffer.BytesRange(1, 17))   // 16 bytes
 	copy(s.requestBodyKey[:], buffer.BytesRange(17, 33)) // 16 bytes
-	var sid sessionId
+	var sid sessionID
 	copy(sid.user[:], vmessAccount.ID.Bytes())
 	sid.key = s.requestBodyKey
 	sid.nonce = s.requestBodyIV
@@ -226,7 +229,6 @@ func (s *ServerSession) DecodeRequestHeader(reader io.Reader) (*protocol.Request
 		} else {
 			return nil, newError("duplicated session id, possibly under replay attack, but this is a AEAD request")
 		}
-
 	}
 
 	s.responseHeader = buffer.Byte(33)             // 1 byte
@@ -240,6 +242,7 @@ func (s *ServerSession) DecodeRequestHeader(reader io.Reader) (*protocol.Request
 	case protocol.RequestCommandMux:
 		request.Address = net.DomainAddress("v1.mux.cool")
 		request.Port = 0
+
 	case protocol.RequestCommandTCP, protocol.RequestCommandUDP:
 		if addr, port, err := addrParser.ReadAddressPort(buffer, decryptor); err == nil {
 			request.Address = addr
@@ -283,12 +286,11 @@ func (s *ServerSession) DecodeRequestHeader(reader io.Reader) (*protocol.Request
 			if burnErr != nil {
 				Autherr = newError("invalid auth, can't taint legacy userHash").Base(burnErr)
 			}
-			//It is possible that we are under attack described in https://github.com/v2ray/v2ray-core/issues/2523
+			// It is possible that we are under attack described in https://github.com/v2ray/v2ray-core/issues/2523
 			return nil, drainConnection(Autherr)
 		} else {
 			return nil, newError("invalid auth, but this is a AEAD request")
 		}
-
 	}
 
 	if request.Address == nil {
@@ -327,8 +329,8 @@ func (s *ServerSession) DecodeRequestBody(request *protocol.RequestHeader, reade
 			}
 			return crypto.NewAuthenticationReader(auth, sizeParser, reader, protocol.TransferTypePacket, padding)
 		}
-
 		return buf.NewReader(reader)
+
 	case protocol.SecurityType_LEGACY:
 		aesStream := crypto.NewAesDecryptionStream(s.requestBodyKey[:], s.requestBodyIV[:])
 		cryptionReader := crypto.NewCryptionReader(aesStream, reader)
@@ -340,17 +342,17 @@ func (s *ServerSession) DecodeRequestBody(request *protocol.RequestHeader, reade
 			}
 			return crypto.NewAuthenticationReader(auth, sizeParser, cryptionReader, request.Command.TransferType(), padding)
 		}
-
 		return buf.NewReader(cryptionReader)
+
 	case protocol.SecurityType_AES128_GCM:
 		aead := crypto.NewAesGcm(s.requestBodyKey[:])
-
 		auth := &crypto.AEADAuthenticator{
 			AEAD:                    aead,
 			NonceGenerator:          GenerateChunkNonce(s.requestBodyIV[:], uint32(aead.NonceSize())),
 			AdditionalDataGenerator: crypto.GenerateEmptyBytes(),
 		}
 		return crypto.NewAuthenticationReader(auth, sizeParser, reader, request.Command.TransferType(), padding)
+
 	case protocol.SecurityType_CHACHA20_POLY1305:
 		aead, _ := chacha20poly1305.New(GenerateChacha20Poly1305Key(s.requestBodyKey[:]))
 
@@ -360,6 +362,7 @@ func (s *ServerSession) DecodeRequestBody(request *protocol.RequestHeader, reade
 			AdditionalDataGenerator: crypto.GenerateEmptyBytes(),
 		}
 		return crypto.NewAuthenticationReader(auth, sizeParser, reader, request.Command.TransferType(), padding)
+
 	default:
 		panic("Unknown security type.")
 	}
@@ -395,9 +398,8 @@ func (s *ServerSession) EncodeResponseHeader(header *protocol.ResponseHeader, wr
 	}
 
 	if s.isAEADRequest {
-
-		aeadResponseHeaderLengthEncryptionKey := vmessaead.KDF16(s.responseBodyKey[:], vmessaead.KDFSaltConst_AEADRespHeaderLenKey)
-		aeadResponseHeaderLengthEncryptionIV := vmessaead.KDF(s.responseBodyIV[:], vmessaead.KDFSaltConst_AEADRespHeaderLenIV)[:12]
+		aeadResponseHeaderLengthEncryptionKey := vmessaead.KDF16(s.responseBodyKey[:], vmessaead.KDFSaltConstAEADRespHeaderLenKey)
+		aeadResponseHeaderLengthEncryptionIV := vmessaead.KDF(s.responseBodyIV[:], vmessaead.KDFSaltConstAEADRespHeaderLenIV)[:12]
 
 		aeadResponseHeaderLengthEncryptionKeyAESBlock := common.Must2(aes.NewCipher(aeadResponseHeaderLengthEncryptionKey)).(cipher.Block)
 		aeadResponseHeaderLengthEncryptionAEAD := common.Must2(cipher.NewGCM(aeadResponseHeaderLengthEncryptionKeyAESBlock)).(cipher.AEAD)
@@ -411,8 +413,8 @@ func (s *ServerSession) EncodeResponseHeader(header *protocol.ResponseHeader, wr
 		AEADEncryptedLength := aeadResponseHeaderLengthEncryptionAEAD.Seal(nil, aeadResponseHeaderLengthEncryptionIV, aeadResponseHeaderLengthEncryptionBuffer.Bytes(), nil)
 		common.Must2(io.Copy(writer, bytes.NewReader(AEADEncryptedLength)))
 
-		aeadResponseHeaderPayloadEncryptionKey := vmessaead.KDF16(s.responseBodyKey[:], vmessaead.KDFSaltConst_AEADRespHeaderPayloadKey)
-		aeadResponseHeaderPayloadEncryptionIV := vmessaead.KDF(s.responseBodyIV[:], vmessaead.KDFSaltConst_AEADRespHeaderPayloadIV)[:12]
+		aeadResponseHeaderPayloadEncryptionKey := vmessaead.KDF16(s.responseBodyKey[:], vmessaead.KDFSaltConstAEADRespHeaderPayloadKey)
+		aeadResponseHeaderPayloadEncryptionIV := vmessaead.KDF(s.responseBodyIV[:], vmessaead.KDFSaltConstAEADRespHeaderPayloadIV)[:12]
 
 		aeadResponseHeaderPayloadEncryptionKeyAESBlock := common.Must2(aes.NewCipher(aeadResponseHeaderPayloadEncryptionKey)).(cipher.Block)
 		aeadResponseHeaderPayloadEncryptionAEAD := common.Must2(cipher.NewGCM(aeadResponseHeaderPayloadEncryptionKeyAESBlock)).(cipher.AEAD)
@@ -447,8 +449,8 @@ func (s *ServerSession) EncodeResponseBody(request *protocol.RequestHeader, writ
 			}
 			return crypto.NewAuthenticationWriter(auth, sizeParser, writer, protocol.TransferTypePacket, padding)
 		}
-
 		return buf.NewWriter(writer)
+
 	case protocol.SecurityType_LEGACY:
 		if request.Option.Has(protocol.RequestOptionChunkStream) {
 			auth := &crypto.AEADAuthenticator{
@@ -458,17 +460,17 @@ func (s *ServerSession) EncodeResponseBody(request *protocol.RequestHeader, writ
 			}
 			return crypto.NewAuthenticationWriter(auth, sizeParser, s.responseWriter, request.Command.TransferType(), padding)
 		}
-
 		return &buf.SequentialWriter{Writer: s.responseWriter}
+
 	case protocol.SecurityType_AES128_GCM:
 		aead := crypto.NewAesGcm(s.responseBodyKey[:])
-
 		auth := &crypto.AEADAuthenticator{
 			AEAD:                    aead,
 			NonceGenerator:          GenerateChunkNonce(s.responseBodyIV[:], uint32(aead.NonceSize())),
 			AdditionalDataGenerator: crypto.GenerateEmptyBytes(),
 		}
 		return crypto.NewAuthenticationWriter(auth, sizeParser, writer, request.Command.TransferType(), padding)
+
 	case protocol.SecurityType_CHACHA20_POLY1305:
 		aead, _ := chacha20poly1305.New(GenerateChacha20Poly1305Key(s.responseBodyKey[:]))
 
@@ -478,6 +480,7 @@ func (s *ServerSession) EncodeResponseBody(request *protocol.RequestHeader, writ
 			AdditionalDataGenerator: crypto.GenerateEmptyBytes(),
 		}
 		return crypto.NewAuthenticationWriter(auth, sizeParser, writer, request.Command.TransferType(), padding)
+
 	default:
 		panic("Unknown security type.")
 	}
diff --git a/proxy/vmess/outbound/outbound.go b/proxy/vmess/outbound/outbound.go
index 852552397..bb31ad758 100644
--- a/proxy/vmess/outbound/outbound.go
+++ b/proxy/vmess/outbound/outbound.go
@@ -71,7 +71,7 @@ func (h *Handler) Process(ctx context.Context, link *transport.Link, dialer inte
 	if err != nil {
 		return newError("failed to find an available destination").Base(err).AtWarning()
 	}
-	defer conn.Close() //nolint: errcheck
+	defer conn.Close()
 
 	outbound := session.OutboundFromContext(ctx)
 	if outbound == nil || !outbound.Target.IsValid() {
@@ -114,11 +114,11 @@ func (h *Handler) Process(ctx context.Context, link *transport.Link, dialer inte
 	output := link.Writer
 
 	isAEAD := false
-	if !aead_disabled && len(account.AlterIDs) == 0 {
+	if !aeadDisabled && len(account.AlterIDs) == 0 {
 		isAEAD = true
 	}
 
-	session := encoding.NewClientSession(isAEAD, protocol.DefaultIDHash, ctx)
+	session := encoding.NewClientSession(ctx, isAEAD, protocol.DefaultIDHash)
 	sessionPolicy := h.policyManager.ForLevel(request.User.Level)
 
 	ctx, cancel := context.WithCancel(ctx)
@@ -179,7 +179,7 @@ func (h *Handler) Process(ctx context.Context, link *transport.Link, dialer inte
 
 var (
 	enablePadding = false
-	aead_disabled = false
+	aeadDisabled  = false
 )
 
 func shouldEnablePadding(s protocol.SecurityType) bool {
@@ -198,8 +198,8 @@ func init() {
 		enablePadding = true
 	}
 
-	aeadDisabled := platform.NewEnvFlag("v2ray.vmess.aead.disabled").GetValue(func() string { return defaultFlagValue })
-	if aeadDisabled == "true" {
-		aead_disabled = true
+	isAeadDisabled := platform.NewEnvFlag("v2ray.vmess.aead.disabled").GetValue(func() string { return defaultFlagValue })
+	if isAeadDisabled == "true" {
+		aeadDisabled = true
 	}
 }
diff --git a/proxy/vmess/validator.go b/proxy/vmess/validator.go
index e308255bf..512337448 100644
--- a/proxy/vmess/validator.go
+++ b/proxy/vmess/validator.go
@@ -5,7 +5,6 @@ package vmess
 import (
 	"crypto/hmac"
 	"crypto/sha256"
-	"hash"
 	"hash/crc64"
 	"strings"
 	"sync"
@@ -142,7 +141,7 @@ func (v *TimedUserValidator) Add(u *protocol.MemoryUser) error {
 
 	account := uu.user.Account.(*MemoryAccount)
 	if !v.behaviorFused {
-		hashkdf := hmac.New(func() hash.Hash { return sha256.New() }, []byte("VMESSBSKDF"))
+		hashkdf := hmac.New(sha256.New, []byte("VMESSBSKDF"))
 		hashkdf.Write(account.ID.Bytes())
 		v.behaviorSeed = crc64.Update(v.behaviorSeed, crc64.MakeTable(crc64.ECMA), hashkdf.Sum(nil))
 	}
diff --git a/testing/scenarios/command_test.go b/testing/scenarios/command_test.go
index 4f9ab9749..daf48244c 100644
--- a/testing/scenarios/command_test.go
+++ b/testing/scenarios/command_test.go
@@ -3,13 +3,13 @@ package scenarios
 import (
 	"context"
 	"fmt"
-	"github.com/google/go-cmp/cmp/cmpopts"
 	"io"
 	"strings"
 	"testing"
 	"time"
 
 	"github.com/google/go-cmp/cmp"
+	"github.com/google/go-cmp/cmp/cmpopts"
 	"google.golang.org/grpc"
 
 	"v2ray.com/core"
diff --git a/testing/scenarios/common.go b/testing/scenarios/common.go
index fe105922f..d3ba1e863 100644
--- a/testing/scenarios/common.go
+++ b/testing/scenarios/common.go
@@ -203,6 +203,5 @@ func testTCPConn2(conn net.Conn, payloadSize int, timeout time.Duration) func()
 		}
 
 		return nil
-
 	}
 }
diff --git a/testing/scenarios/http_test.go b/testing/scenarios/http_test.go
index 9516ca6ab..aca61c41f 100644
--- a/testing/scenarios/http_test.go
+++ b/testing/scenarios/http_test.go
@@ -2,6 +2,7 @@ package scenarios
 
 import (
 	"bytes"
+	"context"
 	"crypto/rand"
 	"io"
 	"io/ioutil"
@@ -136,7 +137,7 @@ func TestHttpError(t *testing.T) {
 	}
 }
 
-func TestHttpConnectMethod(t *testing.T) {
+func TestHTTPConnectMethod(t *testing.T) {
 	tcpServer := tcp.Server{
 		MsgProcessor: xor,
 	}
@@ -179,7 +180,9 @@ func TestHttpConnectMethod(t *testing.T) {
 
 		payload := make([]byte, 1024*64)
 		common.Must2(rand.Read(payload))
-		req, err := http.NewRequest("Connect", "http://"+dest.NetAddr()+"/", bytes.NewReader(payload))
+
+		ctx := context.Background()
+		req, err := http.NewRequestWithContext(ctx, "Connect", "http://"+dest.NetAddr()+"/", bytes.NewReader(payload))
 		req.Header.Set("X-a", "b")
 		req.Header.Set("X-b", "d")
 		common.Must(err)
@@ -334,7 +337,8 @@ func TestHttpBasicAuth(t *testing.T) {
 		}
 
 		{
-			req, err := http.NewRequest("GET", "http://127.0.0.1:"+httpServerPort.String(), nil)
+			ctx := context.Background()
+			req, err := http.NewRequestWithContext(ctx, "GET", "http://127.0.0.1:"+httpServerPort.String(), nil)
 			common.Must(err)
 
 			setProxyBasicAuth(req, "a", "c")
@@ -346,7 +350,8 @@ func TestHttpBasicAuth(t *testing.T) {
 		}
 
 		{
-			req, err := http.NewRequest("GET", "http://127.0.0.1:"+httpServerPort.String(), nil)
+			ctx := context.Background()
+			req, err := http.NewRequestWithContext(ctx, "GET", "http://127.0.0.1:"+httpServerPort.String(), nil)
 			common.Must(err)
 
 			setProxyBasicAuth(req, "a", "b")
diff --git a/testing/scenarios/shadowsocks_test.go b/testing/scenarios/shadowsocks_test.go
index 368a67d47..322c2a3d3 100644
--- a/testing/scenarios/shadowsocks_test.go
+++ b/testing/scenarios/shadowsocks_test.go
@@ -226,7 +226,7 @@ func TestShadowsocksAES128UDP(t *testing.T) {
 			payload := make([]byte, 1024)
 			common.Must2(rand.Read(payload))
 
-			nBytes, err := conn.Write([]byte(payload))
+			nBytes, err := conn.Write(payload)
 			if err != nil {
 				return err
 			}
diff --git a/testing/scenarios/transport_test.go b/testing/scenarios/transport_test.go
index 65ba87606..b61db43d1 100644
--- a/testing/scenarios/transport_test.go
+++ b/testing/scenarios/transport_test.go
@@ -31,7 +31,7 @@ import (
 	tcptransport "v2ray.com/core/transport/internet/tcp"
 )
 
-func TestHttpConnectionHeader(t *testing.T) {
+func TestHTTPConnectionHeader(t *testing.T) {
 	tcpServer := tcp.Server{
 		MsgProcessor: xor,
 	}
diff --git a/testing/servers/http/http.go b/testing/servers/http/http.go
index 379da590e..8ba591a7f 100644
--- a/testing/servers/http/http.go
+++ b/testing/servers/http/http.go
@@ -32,7 +32,7 @@ func (s *Server) Start() (net.Destination, error) {
 		Handler: s,
 	}
 	go s.server.ListenAndServe()
-	return net.TCPDestination(net.LocalHostIP, net.Port(s.Port)), nil
+	return net.TCPDestination(net.LocalHostIP, s.Port), nil
 }
 
 func (s *Server) Close() error {
diff --git a/testing/servers/tcp/tcp.go b/testing/servers/tcp/tcp.go
index 3e0d46db2..ef366f388 100644
--- a/testing/servers/tcp/tcp.go
+++ b/testing/servers/tcp/tcp.go
@@ -65,7 +65,7 @@ func (server *Server) handleConnection(conn net.Conn) {
 
 	pReader, pWriter := pipe.New(pipe.WithoutSizeLimit())
 	err := task.Run(context.Background(), func() error {
-		defer pWriter.Close() // nolint: errcheck
+		defer pWriter.Close()
 
 		for {
 			b := buf.New()
@@ -102,7 +102,7 @@ func (server *Server) handleConnection(conn net.Conn) {
 		fmt.Println("failed to transfer data: ", err.Error())
 	}
 
-	conn.Close() // nolint: errcheck
+	conn.Close()
 }
 
 func (server *Server) Close() error {
diff --git a/transport/internet/domainsocket/config.go b/transport/internet/domainsocket/config.go
index 652162126..f51879476 100644
--- a/transport/internet/domainsocket/config.go
+++ b/transport/internet/domainsocket/config.go
@@ -22,9 +22,7 @@ func (c *Config) GetUnixAddr() (*net.UnixAddr, error) {
 	if c.Abstract && c.Padding {
 		raw := []byte(path)
 		addr := make([]byte, sizeofSunPath)
-		for i, c := range raw {
-			addr[i] = c
-		}
+		copy(addr, raw)
 		path = string(addr)
 	}
 	return &net.UnixAddr{
diff --git a/transport/internet/headers/http/config.go b/transport/internet/headers/http/config.go
index 32a068eb8..0f4c2b172 100644
--- a/transport/internet/headers/http/config.go
+++ b/transport/internet/headers/http/config.go
@@ -18,7 +18,7 @@ func pickString(arr []string) string {
 	}
 }
 
-func (v *RequestConfig) PickUri() string {
+func (v *RequestConfig) PickURI() string {
 	return pickString(v.Uri)
 }
 
diff --git a/transport/internet/headers/http/http.go b/transport/internet/headers/http/http.go
index c12d5b035..f00e11b94 100644
--- a/transport/internet/headers/http/http.go
+++ b/transport/internet/headers/http/http.go
@@ -109,24 +109,23 @@ func (h *HeaderReader) Read(reader io.Reader) (*buf.Buffer, error) {
 		return buffer, nil
 	}
 
-	//Parse the request
-
+	// Parse the request
 	if req, err := readRequest(bufio.NewReader(bytes.NewReader(headerBuf.Bytes())), false); err != nil {
 		return nil, err
 	} else {
 		h.req = req
 	}
 
-	//Check req
+	// Check req
 	path := h.req.URL.Path
-	hasThisUri := false
+	hasThisURI := false
 	for _, u := range h.expectedHeader.Uri {
 		if u == path {
-			hasThisUri = true
+			hasThisURI = true
 		}
 	}
 
-	if !hasThisUri {
+	if !hasThisURI {
 		return nil, ErrHeaderMisMatch
 	}
 
@@ -158,7 +157,7 @@ func (w *HeaderWriter) Write(writer io.Writer) error {
 	return err
 }
 
-type HttpConn struct {
+type Conn struct {
 	net.Conn
 
 	readBuffer          *buf.Buffer
@@ -167,12 +166,11 @@ type HttpConn struct {
 	errorWriter         Writer
 	errorMismatchWriter Writer
 	errorTooLongWriter  Writer
-
-	errReason error
+	errReason           error
 }
 
-func NewHttpConn(conn net.Conn, reader Reader, writer Writer, errorWriter Writer, errorMismatchWriter Writer, errorTooLongWriter Writer) *HttpConn {
-	return &HttpConn{
+func NewConn(conn net.Conn, reader Reader, writer Writer, errorWriter Writer, errorMismatchWriter Writer, errorTooLongWriter Writer) *Conn {
+	return &Conn{
 		Conn:                conn,
 		oneTimeReader:       reader,
 		oneTimeWriter:       writer,
@@ -182,7 +180,7 @@ func NewHttpConn(conn net.Conn, reader Reader, writer Writer, errorWriter Writer
 	}
 }
 
-func (c *HttpConn) Read(b []byte) (int, error) {
+func (c *Conn) Read(b []byte) (int, error) {
 	if c.oneTimeReader != nil {
 		buffer, err := c.oneTimeReader.Read(c.Conn)
 		if err != nil {
@@ -206,7 +204,7 @@ func (c *HttpConn) Read(b []byte) (int, error) {
 }
 
 // Write implements io.Writer.
-func (c *HttpConn) Write(b []byte) (int, error) {
+func (c *Conn) Write(b []byte) (int, error) {
 	if c.oneTimeWriter != nil {
 		err := c.oneTimeWriter.Write(c.Conn)
 		c.oneTimeWriter = nil
@@ -219,18 +217,18 @@ func (c *HttpConn) Write(b []byte) (int, error) {
 }
 
 // Close implements net.Conn.Close().
-func (c *HttpConn) Close() error {
+func (c *Conn) Close() error {
 	if c.oneTimeWriter != nil && c.errorWriter != nil {
 		// Connection is being closed but header wasn't sent. This means the client request
 		// is probably not valid. Sending back a server error header in this case.
 
-		//Write response based on error reason
-
-		if c.errReason == ErrHeaderMisMatch {
+		// Write response based on error reason
+		switch c.errReason {
+		case ErrHeaderMisMatch:
 			c.errorMismatchWriter.Write(c.Conn)
-		} else if c.errReason == ErrHeaderToLong {
+		case ErrHeaderToLong:
 			c.errorTooLongWriter.Write(c.Conn)
-		} else {
+		default:
 			c.errorWriter.Write(c.Conn)
 		}
 	}
@@ -259,14 +257,14 @@ func formResponseHeader(config *ResponseConfig) *HeaderWriter {
 	}
 }
 
-type HttpAuthenticator struct {
+type Authenticator struct {
 	config *Config
 }
 
-func (a HttpAuthenticator) GetClientWriter() *HeaderWriter {
+func (a Authenticator) GetClientWriter() *HeaderWriter {
 	header := buf.New()
 	config := a.config.Request
-	common.Must2(header.WriteString(strings.Join([]string{config.GetMethodValue(), config.PickUri(), config.GetFullVersion()}, " ")))
+	common.Must2(header.WriteString(strings.Join([]string{config.GetMethodValue(), config.PickURI(), config.GetFullVersion()}, " ")))
 	common.Must2(header.WriteString(CRLF))
 
 	headers := config.PickHeaders()
@@ -280,11 +278,11 @@ func (a HttpAuthenticator) GetClientWriter() *HeaderWriter {
 	}
 }
 
-func (a HttpAuthenticator) GetServerWriter() *HeaderWriter {
+func (a Authenticator) GetServerWriter() *HeaderWriter {
 	return formResponseHeader(a.config.Response)
 }
 
-func (a HttpAuthenticator) Client(conn net.Conn) net.Conn {
+func (a Authenticator) Client(conn net.Conn) net.Conn {
 	if a.config.Request == nil && a.config.Response == nil {
 		return conn
 	}
@@ -297,27 +295,27 @@ func (a HttpAuthenticator) Client(conn net.Conn) net.Conn {
 	if a.config.Response != nil {
 		writer = a.GetClientWriter()
 	}
-	return NewHttpConn(conn, reader, writer, NoOpWriter{}, NoOpWriter{}, NoOpWriter{})
+	return NewConn(conn, reader, writer, NoOpWriter{}, NoOpWriter{}, NoOpWriter{})
 }
 
-func (a HttpAuthenticator) Server(conn net.Conn) net.Conn {
+func (a Authenticator) Server(conn net.Conn) net.Conn {
 	if a.config.Request == nil && a.config.Response == nil {
 		return conn
 	}
-	return NewHttpConn(conn, new(HeaderReader).ExpectThisRequest(a.config.Request), a.GetServerWriter(),
+	return NewConn(conn, new(HeaderReader).ExpectThisRequest(a.config.Request), a.GetServerWriter(),
 		formResponseHeader(resp400),
 		formResponseHeader(resp404),
 		formResponseHeader(resp400))
 }
 
-func NewHttpAuthenticator(ctx context.Context, config *Config) (HttpAuthenticator, error) {
-	return HttpAuthenticator{
+func NewAuthenticator(ctx context.Context, config *Config) (Authenticator, error) {
+	return Authenticator{
 		config: config,
 	}, nil
 }
 
 func init() {
 	common.Must(common.RegisterConfig((*Config)(nil), func(ctx context.Context, config interface{}) (interface{}, error) {
-		return NewHttpAuthenticator(ctx, config.(*Config))
+		return NewAuthenticator(ctx, config.(*Config))
 	}))
 }
diff --git a/transport/internet/headers/http/http_test.go b/transport/internet/headers/http/http_test.go
index 54fcaf664..95b180bfb 100644
--- a/transport/internet/headers/http/http_test.go
+++ b/transport/internet/headers/http/http_test.go
@@ -41,7 +41,7 @@ func TestReaderWriter(t *testing.T) {
 }
 
 func TestRequestHeader(t *testing.T) {
-	auth, err := NewHttpAuthenticator(context.Background(), &Config{
+	auth, err := NewAuthenticator(context.Background(), &Config{
 		Request: &RequestConfig{
 			Uri: []string{"/"},
 			Header: []*Header{
@@ -66,7 +66,7 @@ func TestRequestHeader(t *testing.T) {
 func TestLongRequestHeader(t *testing.T) {
 	payload := make([]byte, buf.Size+2)
 	common.Must2(rand.Read(payload[:buf.Size-2]))
-	copy(payload[buf.Size-2:], []byte(ENDING))
+	copy(payload[buf.Size-2:], ENDING)
 	payload = append(payload, []byte("abcd")...)
 
 	reader := HeaderReader{}
@@ -84,7 +84,7 @@ func TestLongRequestHeader(t *testing.T) {
 }
 
 func TestConnection(t *testing.T) {
-	auth, err := NewHttpAuthenticator(context.Background(), &Config{
+	auth, err := NewAuthenticator(context.Background(), &Config{
 		Request: &RequestConfig{
 			Method: &Method{Value: "Post"},
 			Uri:    []string{"/testpath"},
@@ -157,7 +157,7 @@ func TestConnection(t *testing.T) {
 }
 
 func TestConnectionInvPath(t *testing.T) {
-	auth, err := NewHttpAuthenticator(context.Background(), &Config{
+	auth, err := NewAuthenticator(context.Background(), &Config{
 		Request: &RequestConfig{
 			Method: &Method{Value: "Post"},
 			Uri:    []string{"/testpath"},
@@ -184,7 +184,7 @@ func TestConnectionInvPath(t *testing.T) {
 	})
 	common.Must(err)
 
-	authR, err := NewHttpAuthenticator(context.Background(), &Config{
+	authR, err := NewAuthenticator(context.Background(), &Config{
 		Request: &RequestConfig{
 			Method: &Method{Value: "Post"},
 			Uri:    []string{"/testpathErr"},
@@ -258,7 +258,7 @@ func TestConnectionInvPath(t *testing.T) {
 }
 
 func TestConnectionInvReq(t *testing.T) {
-	auth, err := NewHttpAuthenticator(context.Background(), &Config{
+	auth, err := NewAuthenticator(context.Background(), &Config{
 		Request: &RequestConfig{
 			Method: &Method{Value: "Post"},
 			Uri:    []string{"/testpath"},
diff --git a/transport/internet/headers/utp/utp.go b/transport/internet/headers/utp/utp.go
index 0ed164ca9..e210cc3bd 100644
--- a/transport/internet/headers/utp/utp.go
+++ b/transport/internet/headers/utp/utp.go
@@ -11,7 +11,7 @@ import (
 type UTP struct {
 	header       byte
 	extension    byte
-	connectionId uint16
+	connectionID uint16
 }
 
 func (*UTP) Size() int32 {
@@ -20,7 +20,7 @@ func (*UTP) Size() int32 {
 
 // Serialize implements PacketHeader.
 func (u *UTP) Serialize(b []byte) {
-	binary.BigEndian.PutUint16(b, u.connectionId)
+	binary.BigEndian.PutUint16(b, u.connectionID)
 	b[2] = u.header
 	b[3] = u.extension
 }
@@ -30,7 +30,7 @@ func New(ctx context.Context, config interface{}) (interface{}, error) {
 	return &UTP{
 		header:       1,
 		extension:    0,
-		connectionId: dice.RollUint16(),
+		connectionID: dice.RollUint16(),
 	}, nil
 }
 
diff --git a/transport/internet/http/dialer.go b/transport/internet/http/dialer.go
index ffa727417..4a32b9fe3 100644
--- a/transport/internet/http/dialer.go
+++ b/transport/internet/http/dialer.go
@@ -23,7 +23,7 @@ var (
 	globalDialerAccess sync.Mutex
 )
 
-func getHTTPClient(ctx context.Context, dest net.Destination, tlsSettings *tls.Config) (*http.Client, error) {
+func getHTTPClient(_ context.Context, dest net.Destination, tlsSettings *tls.Config) (*http.Client, error) {
 	globalDialerAccess.Lock()
 	defer globalDialerAccess.Unlock()
 
diff --git a/transport/internet/kcp/config.go b/transport/internet/kcp/config.go
index f60161858..3179e9c7e 100644
--- a/transport/internet/kcp/config.go
+++ b/transport/internet/kcp/config.go
@@ -4,6 +4,7 @@ package kcp
 
 import (
 	"crypto/cipher"
+
 	"v2ray.com/core/common"
 	"v2ray.com/core/transport/internet"
 )
diff --git a/transport/internet/kcp/connection.go b/transport/internet/kcp/connection.go
index e5227ecd5..b89e1da69 100644
--- a/transport/internet/kcp/connection.go
+++ b/transport/internet/kcp/connection.go
@@ -532,7 +532,7 @@ func (c *Connection) Terminate() {
 	}
 	newError("#", c.meta.Conversation, " terminating connection to ", c.RemoteAddr()).WriteToLog()
 
-	//v.SetState(StateTerminated)
+	// v.SetState(StateTerminated)
 	c.dataInput.Signal()
 	c.dataOutput.Signal()
 
diff --git a/transport/internet/kcp/cryptreal.go b/transport/internet/kcp/cryptreal.go
index 124ec4133..aca8e6fe6 100644
--- a/transport/internet/kcp/cryptreal.go
+++ b/transport/internet/kcp/cryptreal.go
@@ -4,6 +4,7 @@ import (
 	"crypto/aes"
 	"crypto/cipher"
 	"crypto/sha256"
+
 	"v2ray.com/core/common"
 )
 
diff --git a/transport/internet/kcp/dialer.go b/transport/internet/kcp/dialer.go
index bc481ae3d..83050edc0 100644
--- a/transport/internet/kcp/dialer.go
+++ b/transport/internet/kcp/dialer.go
@@ -20,7 +20,7 @@ var (
 	globalConv = uint32(dice.RollUint16())
 )
 
-func fetchInput(ctx context.Context, input io.Reader, reader PacketReader, conn *Connection) {
+func fetchInput(_ context.Context, input io.Reader, reader PacketReader, conn *Connection) {
 	cache := make(chan *buf.Buffer, 1024)
 	go func() {
 		for {
diff --git a/transport/internet/kcp/io_test.go b/transport/internet/kcp/io_test.go
index 68838fc81..9a4b6e2c1 100644
--- a/transport/internet/kcp/io_test.go
+++ b/transport/internet/kcp/io_test.go
@@ -33,5 +33,4 @@ func TestKCPPacketReader(t *testing.T) {
 			t.Errorf("Expect some output, but got nil")
 		}
 	}
-
 }
diff --git a/transport/internet/quic/hub.go b/transport/internet/quic/hub.go
index 372d96e8d..9e4947595 100644
--- a/transport/internet/quic/hub.go
+++ b/transport/internet/quic/hub.go
@@ -50,7 +50,6 @@ func (l *Listener) acceptStreams(session quic.Session) {
 
 		l.addConn(conn)
 	}
-
 }
 
 func (l *Listener) keepAccepting() {
diff --git a/transport/internet/tls/config.go b/transport/internet/tls/config.go
index 32035c47a..2d55998b6 100644
--- a/transport/internet/tls/config.go
+++ b/transport/internet/tls/config.go
@@ -22,11 +22,14 @@ const exp8357 = "experiment:8357"
 
 // ParseCertificate converts a cert.Certificate to Certificate.
 func ParseCertificate(c *cert.Certificate) *Certificate {
-	certPEM, keyPEM := c.ToPEM()
-	return &Certificate{
-		Certificate: certPEM,
-		Key:         keyPEM,
+	if c != nil {
+		certPEM, keyPEM := c.ToPEM()
+		return &Certificate{
+			Certificate: certPEM,
+			Key:         keyPEM,
+		}
 	}
+	return nil
 }
 
 func (c *Config) loadSelfCertPool() (*x509.CertPool, error) {
@@ -173,6 +176,16 @@ func (c *Config) GetTLSConfig(opts ...Option) *tls.Config {
 		newError("failed to load system root certificate").AtError().Base(err).WriteToLog()
 	}
 
+	if c == nil {
+		return &tls.Config{
+			ClientSessionCache:     globalSessionCache,
+			RootCAs:                root,
+			InsecureSkipVerify:     false,
+			NextProtos:             nil,
+			SessionTicketsDisabled: false,
+		}
+	}
+
 	config := &tls.Config{
 		ClientSessionCache:     globalSessionCache,
 		RootCAs:                root,
@@ -180,9 +193,6 @@ func (c *Config) GetTLSConfig(opts ...Option) *tls.Config {
 		NextProtos:             c.NextProtocol,
 		SessionTicketsDisabled: c.DisableSessionResumption,
 	}
-	if c == nil {
-		return config
-	}
 
 	for _, opt := range opts {
 		opt(config)
diff --git a/transport/internet/udp/hub.go b/transport/internet/udp/hub.go
index d1c7992cd..d9a00b1b9 100644
--- a/transport/internet/udp/hub.go
+++ b/transport/internet/udp/hub.go
@@ -119,7 +119,6 @@ func (h *Hub) start() {
 			buffer.Release()
 			payload.Payload = nil
 		}
-
 	}
 }
 
diff --git a/transport/internet/websocket/ws_test.go b/transport/internet/websocket/ws_test.go
index db919b342..0cfb3697a 100644
--- a/transport/internet/websocket/ws_test.go
+++ b/transport/internet/websocket/ws_test.go
@@ -81,7 +81,7 @@ func TestDialWithRemoteAddr(t *testing.T) {
 
 			var b [1024]byte
 			_, err := c.Read(b[:])
-			//common.Must(err)
+			// common.Must(err)
 			if err != nil {
 				return
 			}
diff --git a/transport/internet/xtls/config.go b/transport/internet/xtls/config.go
index 580d1cead..0fc2708f6 100644
--- a/transport/internet/xtls/config.go
+++ b/transport/internet/xtls/config.go
@@ -20,11 +20,14 @@ var (
 
 // ParseCertificate converts a cert.Certificate to Certificate.
 func ParseCertificate(c *cert.Certificate) *Certificate {
-	certPEM, keyPEM := c.ToPEM()
-	return &Certificate{
-		Certificate: certPEM,
-		Key:         keyPEM,
+	if c != nil {
+		certPEM, keyPEM := c.ToPEM()
+		return &Certificate{
+			Certificate: certPEM,
+			Key:         keyPEM,
+		}
 	}
+	return nil
 }
 
 func (c *Config) loadSelfCertPool() (*x509.CertPool, error) {
@@ -163,6 +166,16 @@ func (c *Config) GetXTLSConfig(opts ...Option) *xtls.Config {
 		newError("failed to load system root certificate").AtError().Base(err).WriteToLog()
 	}
 
+	if c == nil {
+		return &xtls.Config{
+			ClientSessionCache:     globalSessionCache,
+			RootCAs:                root,
+			InsecureSkipVerify:     false,
+			NextProtos:             nil,
+			SessionTicketsDisabled: false,
+		}
+	}
+
 	config := &xtls.Config{
 		ClientSessionCache:     globalSessionCache,
 		RootCAs:                root,
@@ -170,9 +183,6 @@ func (c *Config) GetXTLSConfig(opts ...Option) *xtls.Config {
 		NextProtos:             c.NextProtocol,
 		SessionTicketsDisabled: c.DisableSessionResumption,
 	}
-	if c == nil {
-		return config
-	}
 
 	for _, opt := range opts {
 		opt(config)
diff --git a/v2ray.go b/v2ray.go
index b9e868d9a..0dfd8b5a5 100644
--- a/v2ray.go
+++ b/v2ray.go
@@ -161,7 +161,7 @@ func RequireFeatures(ctx context.Context, callback interface{}) error {
 func New(config *Config) (*Instance, error) {
 	var server = &Instance{ctx: context.Background()}
 
-	err, done := initInstanceWithConfig(config, server)
+	done, err := initInstanceWithConfig(config, server)
 	if done {
 		return nil, err
 	}
@@ -169,10 +169,10 @@ func New(config *Config) (*Instance, error) {
 	return server, nil
 }
 
-func NewWithContext(config *Config, ctx context.Context) (*Instance, error) {
+func NewWithContext(ctx context.Context, config *Config) (*Instance, error) {
 	var server = &Instance{ctx: ctx}
 
-	err, done := initInstanceWithConfig(config, server)
+	done, err := initInstanceWithConfig(config, server)
 	if done {
 		return nil, err
 	}
@@ -180,26 +180,26 @@ func NewWithContext(config *Config, ctx context.Context) (*Instance, error) {
 	return server, nil
 }
 
-func initInstanceWithConfig(config *Config, server *Instance) (error, bool) {
+func initInstanceWithConfig(config *Config, server *Instance) (bool, error) {
 	if config.Transport != nil {
 		features.PrintDeprecatedFeatureWarning("global transport settings")
 	}
 	if err := config.Transport.Apply(); err != nil {
-		return err, true
+		return true, err
 	}
 
 	for _, appSettings := range config.App {
 		settings, err := appSettings.GetInstance()
 		if err != nil {
-			return err, true
+			return true, err
 		}
 		obj, err := CreateObject(server, settings)
 		if err != nil {
-			return err, true
+			return true, err
 		}
 		if feature, ok := obj.(features.Feature); ok {
 			if err := server.AddFeature(feature); err != nil {
-				return err, true
+				return true, err
 			}
 		}
 	}
@@ -217,23 +217,23 @@ func initInstanceWithConfig(config *Config, server *Instance) (error, bool) {
 	for _, f := range essentialFeatures {
 		if server.GetFeature(f.Type) == nil {
 			if err := server.AddFeature(f.Instance); err != nil {
-				return err, true
+				return true, err
 			}
 		}
 	}
 
 	if server.featureResolutions != nil {
-		return newError("not all dependency are resolved."), true
+		return true, newError("not all dependency are resolved.")
 	}
 
 	if err := addInboundHandlers(server, config.Inbound); err != nil {
-		return err, true
+		return true, err
 	}
 
 	if err := addOutboundHandlers(server, config.Outbound); err != nil {
-		return err, true
+		return true, err
 	}
-	return nil, false
+	return false, nil
 }
 
 // Type implements common.HasType.
diff --git a/v2ray_test.go b/v2ray_test.go
index 8b93d5c5f..982f44ed5 100644
--- a/v2ray_test.go
+++ b/v2ray_test.go
@@ -38,7 +38,7 @@ func TestV2RayDependency(t *testing.T) {
 func TestV2RayClose(t *testing.T) {
 	port := tcp.PickPort()
 
-	userId := uuid.New()
+	userID := uuid.New()
 	config := &Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&dispatcher.Config{}),
@@ -70,7 +70,7 @@ func TestV2RayClose(t *testing.T) {
 							User: []*protocol.User{
 								{
 									Account: serial.ToTypedMessage(&vmess.Account{
-										Id: userId.String(),
+										Id: userID.String(),
 									}),
 								},
 							},