Fix: the priority of fake-ip-filter

Co-authored-by: Dreamacro <8615343+Dreamacro@users.noreply.github.com>

.github/workflows/docker.yml

@@ -19,10 +19,9 @@ jobs:
 
       - name: Set up docker buildx
         id: buildx
-        uses: crazy-max/ghaction-docker-buildx@v2
+        uses: crazy-max/ghaction-docker-buildx@v3
         with:
           buildx-version: latest
-          skip-cache: false
           qemu-version: latest
 
       - name: Docker login
@@ -39,7 +38,7 @@ jobs:
 
       - name: Replace tag without `v`
         if: startsWith(github.ref, 'refs/tags/')
-        uses: actions/github-script@v1
+        uses: actions/github-script@v3
         id: version
         with:
           script: |

.github/workflows/go.yml

@@ -22,9 +22,12 @@ jobs:
           restore-keys: |
             ${{ runner.os }}-go-
 
-      - name: Get dependencies and run test
+      - name: Get dependencies, run test and static check
         run: |
           go test ./...
+          go vet ./...
+          go get -u honnef.co/go/tools/cmd/staticcheck
+          staticcheck -- $(go list ./...)
 
       - name: Build
         if: startsWith(github.ref, 'refs/tags/')

.github/workflows/stale.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/stale@v1
+      - uses: actions/stale@v3
         with:
           repo-token: ${{ secrets.GITHUB_TOKEN }}
           stale-issue-message: 'This issue is stale because it has been open 120 days with no activity. Remove stale label or comment or this will be closed in 5 days'

Makefile

@@ -4,7 +4,7 @@ VERSION=$(shell git describe --tags || echo "unknown version")
 BUILDTIME=$(shell date -u)
 GOBUILD=CGO_ENABLED=0 go build -trimpath -ldflags '-X "github.com/Dreamacro/clash/constant.Version=$(VERSION)" \
 		-X "github.com/Dreamacro/clash/constant.BuildTime=$(BUILDTIME)" \
-		-w -s'
+		-w -s -buildid='
 
 PLATFORM_LIST = \
 	darwin-amd64 \
@@ -25,7 +25,8 @@ PLATFORM_LIST = \
 
 WINDOWS_ARCH_LIST = \
 	windows-386 \
-	windows-amd64
+	windows-amd64 \
+	windows-arm32v7
 
 all: linux-amd64 darwin-amd64 windows-amd64 # Most used
 
@@ -82,6 +83,9 @@ windows-386:
 
 windows-amd64:
 	GOARCH=amd64 GOOS=windows $(GOBUILD) -o $(BINDIR)/$(NAME)-$@.exe
+	
+windows-arm32v7:
+	GOARCH=arm GOOS=windows GOARM=7 $(GOBUILD) -o $(BINDIR)/$(NAME)-$@.exe
 
 gz_releases=$(addsuffix .gz, $(PLATFORM_LIST))
 zip_releases=$(addsuffix .zip, $(WINDOWS_ARCH_LIST))

adapters/outbound/base.go

@@ -13,10 +13,6 @@ import (
 	C "github.com/Dreamacro/clash/constant"
 )
 
-var (
-	defaultURLTestTimeout = time.Second * 5
-)
-
 type Base struct {
 	name string
 	addr string

adapters/outbound/http.go

@@ -31,6 +31,7 @@ type HttpOption struct {
 	UserName       string `proxy:"username,omitempty"`
 	Password       string `proxy:"password,omitempty"`
 	TLS            bool   `proxy:"tls,omitempty"`
+	SNI            string `proxy:"sni,omitempty"`
 	SkipCertVerify bool   `proxy:"skip-cert-verify,omitempty"`
 }
 
@@ -114,10 +115,14 @@ func (h *Http) shakeHand(metadata *C.Metadata, rw io.ReadWriter) error {
 func NewHttp(option HttpOption) *Http {
 	var tlsConfig *tls.Config
 	if option.TLS {
+		sni := option.Server
+		if option.SNI != "" {
+			sni = option.SNI
+		}
 		tlsConfig = &tls.Config{
 			InsecureSkipVerify: option.SkipCertVerify,
 			ClientSessionCache: getClientSessionCache(),
-			ServerName:         option.Server,
+			ServerName:         sni,
 		}
 	}
 

adapters/outbound/parser.go

@@ -11,11 +11,13 @@ func ParseProxy(mapping map[string]interface{}) (C.Proxy, error) {
 	decoder := structure.NewDecoder(structure.Option{TagName: "proxy", WeaklyTypedInput: true})
 	proxyType, existType := mapping["type"].(string)
 	if !existType {
-		return nil, fmt.Errorf("Missing type")
+		return nil, fmt.Errorf("missing type")
 	}
 
-	var proxy C.ProxyAdapter
-	err := fmt.Errorf("Cannot parse")
+	var (
+		proxy C.ProxyAdapter
+		err   error
+	)
 	switch proxyType {
 	case "ss":
 		ssOption := &ShadowSocksOption{}
@@ -72,7 +74,7 @@ func ParseProxy(mapping map[string]interface{}) (C.Proxy, error) {
 		}
 		proxy, err = NewTrojan(*trojanOption)
 	default:
-		return nil, fmt.Errorf("Unsupport proxy type: %s", proxyType)
+		return nil, fmt.Errorf("unsupport proxy type: %s", proxyType)
 	}
 
 	if err != nil {

adapters/outbound/snell.go

@@ -16,7 +16,9 @@ import (
 type Snell struct {
 	*Base
 	psk        []byte
+	pool       *snell.Pool
 	obfsOption *simpleObfsOption
+	version    int
 }
 
 type SnellOption struct {
@@ -24,24 +26,47 @@ type SnellOption struct {
 	Server   string                 `proxy:"server"`
 	Port     int                    `proxy:"port"`
 	Psk      string                 `proxy:"psk"`
+	Version  int                    `proxy:"version,omitempty"`
 	ObfsOpts map[string]interface{} `proxy:"obfs-opts,omitempty"`
 }
 
-func (s *Snell) StreamConn(c net.Conn, metadata *C.Metadata) (net.Conn, error) {
-	switch s.obfsOption.Mode {
+type streamOption struct {
+	psk        []byte
+	version    int
+	addr       string
+	obfsOption *simpleObfsOption
+}
+
+func streamConn(c net.Conn, option streamOption) *snell.Snell {
+	switch option.obfsOption.Mode {
 	case "tls":
-		c = obfs.NewTLSObfs(c, s.obfsOption.Host)
+		c = obfs.NewTLSObfs(c, option.obfsOption.Host)
 	case "http":
-		_, port, _ := net.SplitHostPort(s.addr)
-		c = obfs.NewHTTPObfs(c, s.obfsOption.Host, port)
+		_, port, _ := net.SplitHostPort(option.addr)
+		c = obfs.NewHTTPObfs(c, option.obfsOption.Host, port)
 	}
-	c = snell.StreamConn(c, s.psk)
+	return snell.StreamConn(c, option.psk, option.version)
+}
+
+func (s *Snell) StreamConn(c net.Conn, metadata *C.Metadata) (net.Conn, error) {
+	c = streamConn(c, streamOption{s.psk, s.version, s.addr, s.obfsOption})
 	port, _ := strconv.Atoi(metadata.DstPort)
-	err := snell.WriteHeader(c, metadata.String(), uint(port))
+	err := snell.WriteHeader(c, metadata.String(), uint(port), s.version)
 	return c, err
 }
 
 func (s *Snell) DialContext(ctx context.Context, metadata *C.Metadata) (C.Conn, error) {
+	if s.version == snell.Version2 {
+		c, err := s.pool.Get()
+		if err != nil {
+			return nil, err
+		}
+
+		port, _ := strconv.Atoi(metadata.DstPort)
+		err = snell.WriteHeader(c, metadata.String(), uint(port), s.version)
+		return NewConn(c, s), err
+	}
+
 	c, err := dialer.DialContext(ctx, "tcp", s.addr)
 	if err != nil {
 		return nil, fmt.Errorf("%s connect error: %w", s.addr, err)
@@ -66,7 +91,15 @@ func NewSnell(option SnellOption) (*Snell, error) {
 		return nil, fmt.Errorf("snell %s obfs mode error: %s", addr, obfsOption.Mode)
 	}
 
-	return &Snell{
+	// backward compatible
+	if option.Version == 0 {
+		option.Version = snell.DefaultSnellVersion
+	}
+	if option.Version != snell.Version1 && option.Version != snell.Version2 {
+		return nil, fmt.Errorf("snell version error: %d", option.Version)
+	}
+
+	s := &Snell{
 		Base: &Base{
 			name: option.Name,
 			addr: addr,
@@ -74,5 +107,19 @@ func NewSnell(option SnellOption) (*Snell, error) {
 		},
 		psk:        psk,
 		obfsOption: obfsOption,
-	}, nil
+		version:    option.Version,
+	}
+
+	if option.Version == snell.Version2 {
+		s.pool = snell.NewPool(func(ctx context.Context) (*snell.Snell, error) {
+			c, err := dialer.DialContext(ctx, "tcp", addr)
+			if err != nil {
+				return nil, err
+			}
+
+			tcpKeepAlive(c)
+			return streamConn(c, streamOption{psk, option.Version, addr, obfsOption}), nil
+		})
+	}
+	return s, nil
 }

adapters/outbound/vmess.go

@@ -32,6 +32,7 @@ type VmessOption struct {
 	UDP            bool              `proxy:"udp,omitempty"`
 	Network        string            `proxy:"network,omitempty"`
 	HTTPOpts       HTTPOptions       `proxy:"http-opts,omitempty"`
+	HTTP2Opts      HTTP2Options      `proxy:"h2-opts,omitempty"`
 	WSPath         string            `proxy:"ws-path,omitempty"`
 	WSHeaders      map[string]string `proxy:"ws-headers,omitempty"`
 	SkipCertVerify bool              `proxy:"skip-cert-verify,omitempty"`
@@ -44,6 +45,11 @@ type HTTPOptions struct {
 	Headers map[string][]string `proxy:"headers,omitempty"`
 }
 
+type HTTP2Options struct {
+	Host []string `proxy:"host,omitempty"`
+	Path string   `proxy:"path,omitempty"`
+}
+
 func (v *Vmess) StreamConn(c net.Conn, metadata *C.Metadata) (net.Conn, error) {
 	var err error
 	switch v.option.Network {
@@ -71,6 +77,25 @@ func (v *Vmess) StreamConn(c net.Conn, metadata *C.Metadata) (net.Conn, error) {
 		}
 		c, err = vmess.StreamWebsocketConn(c, wsOpts)
 	case "http":
+		// readability first, so just copy default TLS logic
+		if v.option.TLS {
+			host, _, _ := net.SplitHostPort(v.addr)
+			tlsOpts := &vmess.TLSConfig{
+				Host:           host,
+				SkipCertVerify: v.option.SkipCertVerify,
+				SessionCache:   getClientSessionCache(),
+			}
+
+			if v.option.ServerName != "" {
+				tlsOpts.Host = v.option.ServerName
+			}
+
+			c, err = vmess.StreamTLSConn(c, tlsOpts)
+			if err != nil {
+				return nil, err
+			}
+		}
+
 		host, _, _ := net.SplitHostPort(v.addr)
 		httpOpts := &vmess.HTTPConfig{
 			Host:    host,
@@ -80,6 +105,30 @@ func (v *Vmess) StreamConn(c net.Conn, metadata *C.Metadata) (net.Conn, error) {
 		}
 
 		c = vmess.StreamHTTPConn(c, httpOpts)
+	case "h2":
+		host, _, _ := net.SplitHostPort(v.addr)
+		tlsOpts := vmess.TLSConfig{
+			Host:           host,
+			SkipCertVerify: v.option.SkipCertVerify,
+			SessionCache:   getClientSessionCache(),
+			NextProtos:     []string{"h2"},
+		}
+
+		if v.option.ServerName != "" {
+			tlsOpts.Host = v.option.ServerName
+		}
+
+		c, err = vmess.StreamTLSConn(c, &tlsOpts)
+		if err != nil {
+			return nil, err
+		}
+
+		h2Opts := &vmess.H2Config{
+			Hosts: v.option.HTTP2Opts.Host,
+			Path:  v.option.HTTP2Opts.Path,
+		}
+
+		c, err = vmess.StreamH2Conn(c, h2Opts)
 	default:
 		// handle TLS
 		if v.option.TLS {
@@ -152,13 +201,16 @@ func NewVmess(option VmessOption) (*Vmess, error) {
 	if err != nil {
 		return nil, err
 	}
+	if option.Network == "h2" && !option.TLS {
+		return nil, fmt.Errorf("TLS must be true with h2 network")
+	}
 
 	return &Vmess{
 		Base: &Base{
 			name: option.Name,
 			addr: net.JoinHostPort(option.Server, strconv.Itoa(option.Port)),
 			tp:   C.Vmess,
-			udp:  true,
+			udp:  option.UDP,
 		},
 		client: client,
 		option: &option,

adapters/outboundgroup/parser.go

@@ -12,7 +12,6 @@ import (
 var (
 	errFormat            = errors.New("format error")
 	errType              = errors.New("unsupport type")
-	errMissUse           = errors.New("`use` field should not be empty")
 	errMissProxy         = errors.New("`use` or `proxies` missing")
 	errMissHealthCheck   = errors.New("`url` or `interval` missing")
 	errDuplicateProvider = errors.New("`duplicate provider name")
@@ -63,6 +62,10 @@ func ParseProxyGroup(config map[string]interface{}, proxyMap map[string]C.Proxy,
 
 			providers = append(providers, pd)
 		} else {
+			if _, ok := providersMap[groupName]; ok {
+				return nil, errDuplicateProvider
+			}
+
 			// select don't need health check
 			if groupOption.Type == "select" || groupOption.Type == "relay" {
 				hc := provider.NewHealthCheck(ps, "", 0)

adapters/outboundgroup/relay.go

@@ -22,7 +22,7 @@ type Relay struct {
 func (r *Relay) DialContext(ctx context.Context, metadata *C.Metadata) (C.Conn, error) {
 	proxies := r.proxies(metadata)
 	if len(proxies) == 0 {
-		return nil, errors.New("Proxy does not exist")
+		return nil, errors.New("proxy does not exist")
 	}
 	first := proxies[0]
 	last := proxies[len(proxies)-1]

adapters/outboundgroup/selector.go

@@ -64,7 +64,7 @@ func (s *Selector) Set(name string) error {
 		}
 	}
 
-	return errors.New("Proxy does not exist")
+	return errors.New("proxy not exist")
 }
 
 func (s *Selector) Unwrap(metadata *C.Metadata) C.Proxy {

adapters/outboundgroup/urltest.go

@@ -78,7 +78,7 @@ func (u *URLTest) fast() C.Proxy {
 		}
 
 		// tolerance
-		if u.fastNode == nil || u.fastNode.LastDelay() > fast.LastDelay() + u.tolerance {
+		if u.fastNode == nil || u.fastNode.LastDelay() > fast.LastDelay()+u.tolerance {
 			u.fastNode = fast
 		}
 

adapters/provider/provider.go

@@ -120,20 +120,20 @@ func proxiesParse(buf []byte) (interface{}, error) {
 	}
 
 	if schema.Proxies == nil {
-		return nil, errors.New("File must have a `proxies` field")
+		return nil, errors.New("file must have a `proxies` field")
 	}
 
 	proxies := []C.Proxy{}
 	for idx, mapping := range schema.Proxies {
 		proxy, err := outbound.ParseProxy(mapping)
 		if err != nil {
-			return nil, fmt.Errorf("Proxy %d error: %w", idx, err)
+			return nil, fmt.Errorf("proxy %d error: %w", idx, err)
 		}
 		proxies = append(proxies, proxy)
 	}
 
 	if len(proxies) == 0 {
-		return nil, errors.New("File doesn't have any valid proxy")
+		return nil, errors.New("file doesn't have any valid proxy")
 	}
 
 	return proxies, nil

common/cache/lrucache.go

@@ -146,6 +146,23 @@ func (c *LruCache) SetWithExpire(key interface{}, value interface{}, expires tim
 	c.maybeDeleteOldest()
 }
 
+// CloneTo clone and overwrite elements to another LruCache
+func (c *LruCache) CloneTo(n *LruCache) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	n.mu.Lock()
+	defer n.mu.Unlock()
+
+	n.lru = list.New()
+	n.cache = make(map[interface{}]*list.Element)
+
+	for e := c.lru.Front(); e != nil; e = e.Next() {
+		elm := e.Value.(*entry)
+		n.cache[elm.key] = n.lru.PushBack(elm)
+	}
+}
+
 func (c *LruCache) get(key interface{}) *entry {
 	c.mu.Lock()
 	defer c.mu.Unlock()
@@ -171,7 +188,7 @@ func (c *LruCache) get(key interface{}) *entry {
 }
 
 // Delete removes the value associated with a key.
-func (c *LruCache) Delete(key string) {
+func (c *LruCache) Delete(key interface{}) {
 	c.mu.Lock()
 
 	if le, ok := c.cache[key]; ok {

common/cache/lrucache_test.go

@@ -164,3 +164,21 @@ func TestStale(t *testing.T) {
 	assert.Equal(t, tenSecBefore, expires)
 	assert.Equal(t, true, exist)
 }
+
+func TestCloneTo(t *testing.T) {
+	o := NewLRUCache(WithSize(10))
+	o.Set("1", 1)
+	o.Set("2", 2)
+
+	n := NewLRUCache(WithSize(2))
+	n.Set("3", 3)
+	n.Set("4", 4)
+
+	o.CloneTo(n)
+
+	assert.False(t, n.Exist("3"))
+	assert.True(t, n.Exist("1"))
+
+	n.Set("5", 5)
+	assert.False(t, n.Exist("1"))
+}

common/pool/alloc.go

@@ -55,6 +55,8 @@ func (alloc *Allocator) Put(buf []byte) error {
 	if cap(buf) == 0 || cap(buf) > 65536 || cap(buf) != 1<<bits {
 		return errors.New("allocator Put() incorrect buffer size")
 	}
+
+	//lint:ignore SA6002 ignore temporarily
 	alloc.buffers[bits].Put(buf)
 	return nil
 }

common/pool/alloc_test.go

@@ -25,11 +25,11 @@ func TestAllocGet(t *testing.T) {
 func TestAllocPut(t *testing.T) {
 	alloc := NewAllocator()
 	assert.NotNil(t, alloc.Put(nil), "put nil misbehavior")
-	assert.NotNil(t, alloc.Put(make([]byte, 3, 3)), "put elem:3 []bytes misbehavior")
-	assert.Nil(t, alloc.Put(make([]byte, 4, 4)), "put elem:4 []bytes misbehavior")
+	assert.NotNil(t, alloc.Put(make([]byte, 3)), "put elem:3 []bytes misbehavior")
+	assert.Nil(t, alloc.Put(make([]byte, 4)), "put elem:4 []bytes misbehavior")
 	assert.Nil(t, alloc.Put(make([]byte, 1023, 1024)), "put elem:1024 []bytes misbehavior")
-	assert.Nil(t, alloc.Put(make([]byte, 65536, 65536)), "put elem:65536 []bytes misbehavior")
-	assert.NotNil(t, alloc.Put(make([]byte, 65537, 65537)), "put elem:65537 []bytes misbehavior")
+	assert.Nil(t, alloc.Put(make([]byte, 65536)), "put elem:65536 []bytes misbehavior")
+	assert.NotNil(t, alloc.Put(make([]byte, 65537)), "put elem:65537 []bytes misbehavior")
 }
 
 func TestAllocPutThenGet(t *testing.T) {

common/singledo/singledo.go

@@ -24,6 +24,8 @@ type Result struct {
 	Err error
 }
 
+// Do single.Do likes sync.singleFilght
+//lint:ignore ST1008 it likes sync.singleFilght
 func (s *Single) Do(fn func() (interface{}, error)) (v interface{}, err error, shared bool) {
 	s.mux.Lock()
 	now := time.Now()

component/dialer/dialer.go

@@ -147,28 +147,27 @@ func dualStackDialContext(ctx context.Context, network, address string) (net.Con
 	go startRacer(ctx, network+"4", host, false)
 	go startRacer(ctx, network+"6", host, true)
 
-	for {
-		select {
-		case res := <-results:
-			if res.error == nil {
-				return res.Conn, nil
-			}
+	for res := range results {
+		if res.error == nil {
+			return res.Conn, nil
+		}
 
-			if !res.ipv6 {
-				primary = res
+		if !res.ipv6 {
+			primary = res
+		} else {
+			fallback = res
+		}
+
+		if primary.done && fallback.done {
+			if primary.resolved {
+				return nil, primary.error
+			} else if fallback.resolved {
+				return nil, fallback.error
 			} else {
-				fallback = res
-			}
-
-			if primary.done && fallback.done {
-				if primary.resolved {
-					return nil, primary.error
-				} else if fallback.resolved {
-					return nil, fallback.error
-				} else {
-					return nil, primary.error
-				}
+				return nil, primary.error
 			}
 		}
 	}
+
+	return nil, errors.New("never touched")
 }

component/fakeip/pool.go

@@ -89,6 +89,11 @@ func (p *Pool) Gateway() net.IP {
 	return uintToIP(p.gateway)
 }
 
+// PatchFrom clone cache from old pool
+func (p *Pool) PatchFrom(o *Pool) {
+	o.cache.CloneTo(p.cache)
+}
+
 func (p *Pool) get(host string) net.IP {
 	current := p.offset
 	for {
@@ -116,7 +121,7 @@ func ipToUint(ip net.IP) uint32 {
 }
 
 func uintToIP(v uint32) net.IP {
-	return net.IPv4(byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
+	return net.IP{byte(v >> 24), byte(v >> 16), byte(v >> 8), byte(v)}
 }
 
 // New return Pool instance

component/pool/pool.go

@@ -0,0 +1,114 @@
+package pool
+
+import (
+	"context"
+	"runtime"
+	"time"
+)
+
+type Factory = func(context.Context) (interface{}, error)
+
+type entry struct {
+	elm  interface{}
+	time time.Time
+}
+
+type Option func(*pool)
+
+// WithEvict set the evict callback
+func WithEvict(cb func(interface{})) Option {
+	return func(p *pool) {
+		p.evict = cb
+	}
+}
+
+// WithAge defined element max age (millisecond)
+func WithAge(maxAge int64) Option {
+	return func(p *pool) {
+		p.maxAge = maxAge
+	}
+}
+
+// WithSize defined max size of Pool
+func WithSize(maxSize int) Option {
+	return func(p *pool) {
+		p.ch = make(chan interface{}, maxSize)
+	}
+}
+
+// Pool is for GC, see New for detail
+type Pool struct {
+	*pool
+}
+
+type pool struct {
+	ch      chan interface{}
+	factory Factory
+	evict   func(interface{})
+	maxAge  int64
+}
+
+func (p *pool) GetContext(ctx context.Context) (interface{}, error) {
+	now := time.Now()
+	for {
+		select {
+		case item := <-p.ch:
+			elm := item.(*entry)
+			if p.maxAge != 0 && now.Sub(item.(*entry).time).Milliseconds() > p.maxAge {
+				if p.evict != nil {
+					p.evict(elm.elm)
+				}
+				continue
+			}
+
+			return elm.elm, nil
+		default:
+			return p.factory(ctx)
+		}
+	}
+}
+
+func (p *pool) Get() (interface{}, error) {
+	return p.GetContext(context.Background())
+}
+
+func (p *pool) Put(item interface{}) {
+	e := &entry{
+		elm:  item,
+		time: time.Now(),
+	}
+
+	select {
+	case p.ch <- e:
+		return
+	default:
+		// pool is full
+		if p.evict != nil {
+			p.evict(item)
+		}
+		return
+	}
+}
+
+func recycle(p *Pool) {
+	for item := range p.pool.ch {
+		if p.pool.evict != nil {
+			p.pool.evict(item.(*entry).elm)
+		}
+	}
+}
+
+func New(factory Factory, options ...Option) *Pool {
+	p := &pool{
+		ch:      make(chan interface{}, 10),
+		factory: factory,
+	}
+
+	for _, option := range options {
+		option(p)
+	}
+
+	P := &Pool{p}
+	runtime.SetFinalizer(P, recycle)
+	return P
+}

component/pool/pool_test.go

@@ -0,0 +1,73 @@
+package pool
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func lg() Factory {
+	initial := -1
+	return func(context.Context) (interface{}, error) {
+		initial++
+		return initial, nil
+	}
+}
+
+func TestPool_Basic(t *testing.T) {
+	g := lg()
+	pool := New(g)
+
+	elm, _ := pool.Get()
+	assert.Equal(t, 0, elm.(int))
+	pool.Put(elm)
+	elm, _ = pool.Get()
+	assert.Equal(t, 0, elm.(int))
+	elm, _ = pool.Get()
+	assert.Equal(t, 1, elm.(int))
+}
+
+func TestPool_MaxSize(t *testing.T) {
+	g := lg()
+	size := 5
+	pool := New(g, WithSize(size))
+
+	items := []interface{}{}
+
+	for i := 0; i < size; i++ {
+		item, _ := pool.Get()
+		items = append(items, item)
+	}
+
+	extra, _ := pool.Get()
+	assert.Equal(t, size, extra.(int))
+
+	for _, item := range items {
+		pool.Put(item)
+	}
+
+	pool.Put(extra)
+
+	for _, item := range items {
+		elm, _ := pool.Get()
+		assert.Equal(t, item.(int), elm.(int))
+	}
+}
+
+func TestPool_MaxAge(t *testing.T) {
+	g := lg()
+	pool := New(g, WithAge(20))
+
+	elm, _ := pool.Get()
+	pool.Put(elm)
+
+	elm, _ = pool.Get()
+	assert.Equal(t, 0, elm.(int))
+	pool.Put(elm)
+
+	time.Sleep(time.Millisecond * 22)
+	elm, _ = pool.Get()
+	assert.Equal(t, 1, elm.(int))
+}

component/resolver/enhancer.go

@@ -0,0 +1,46 @@
+package resolver
+
+import (
+	"net"
+)
+
+var DefaultHostMapper Enhancer
+
+type Enhancer interface {
+	FakeIPEnabled() bool
+	MappingEnabled() bool
+	IsFakeIP(net.IP) bool
+	FindHostByIP(net.IP) (string, bool)
+}
+
+func FakeIPEnabled() bool {
+	if mapper := DefaultHostMapper; mapper != nil {
+		return mapper.FakeIPEnabled()
+	}
+
+	return false
+}
+
+func MappingEnabled() bool {
+	if mapper := DefaultHostMapper; mapper != nil {
+		return mapper.MappingEnabled()
+	}
+
+	return false
+}
+
+func IsFakeIP(ip net.IP) bool {
+	if mapper := DefaultHostMapper; mapper != nil {
+		return mapper.IsFakeIP(ip)
+	}
+
+	return false
+}
+
+func FindHostByIP(ip net.IP) (string, bool) {
+	if mapper := DefaultHostMapper; mapper != nil {
+		return mapper.FindHostByIP(ip)
+	}
+
+	return "", false
+}

component/snell/cipher.go

@@ -1,21 +1,54 @@
 package snell
 
 import (
+	"crypto/aes"
 	"crypto/cipher"
 
+	"github.com/Dreamacro/go-shadowsocks2/shadowaead"
 	"golang.org/x/crypto/argon2"
+	"golang.org/x/crypto/chacha20poly1305"
 )
 
 type snellCipher struct {
 	psk      []byte
+	keySize  int
 	makeAEAD func(key []byte) (cipher.AEAD, error)
 }
 
-func (sc *snellCipher) KeySize() int  { return 32 }
+func (sc *snellCipher) KeySize() int  { return sc.keySize }
 func (sc *snellCipher) SaltSize() int { return 16 }
 func (sc *snellCipher) Encrypter(salt []byte) (cipher.AEAD, error) {
-	return sc.makeAEAD(argon2.IDKey(sc.psk, salt, 3, 8, 1, uint32(sc.KeySize())))
+	return sc.makeAEAD(snellKDF(sc.psk, salt, sc.KeySize()))
 }
 func (sc *snellCipher) Decrypter(salt []byte) (cipher.AEAD, error) {
-	return sc.makeAEAD(argon2.IDKey(sc.psk, salt, 3, 8, 1, uint32(sc.KeySize())))
+	return sc.makeAEAD(snellKDF(sc.psk, salt, sc.KeySize()))
+}
+
+func snellKDF(psk, salt []byte, keySize int) []byte {
+	// snell use a special kdf function
+	return argon2.IDKey(psk, salt, 3, 8, 1, 32)[:keySize]
+}
+
+func aesGCM(key []byte) (cipher.AEAD, error) {
+	blk, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+	return cipher.NewGCM(blk)
+}
+
+func NewAES128GCM(psk []byte) shadowaead.Cipher {
+	return &snellCipher{
+		psk:      psk,
+		keySize:  16,
+		makeAEAD: aesGCM,
+	}
+}
+
+func NewChacha20Poly1305(psk []byte) shadowaead.Cipher {
+	return &snellCipher{
+		psk:      psk,
+		keySize:  32,
+		makeAEAD: chacha20poly1305.New,
+	}
 }

component/snell/pool.go

@@ -0,0 +1,80 @@
+package snell
+
+import (
+	"context"
+	"net"
+
+	"github.com/Dreamacro/clash/component/pool"
+	"github.com/Dreamacro/go-shadowsocks2/shadowaead"
+)
+
+type Pool struct {
+	pool *pool.Pool
+}
+
+func (p *Pool) Get() (net.Conn, error) {
+	return p.GetContext(context.Background())
+}
+
+func (p *Pool) GetContext(ctx context.Context) (net.Conn, error) {
+	elm, err := p.pool.GetContext(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	return &PoolConn{elm.(*Snell), p}, nil
+}
+
+func (p *Pool) Put(conn net.Conn) {
+	if err := HalfClose(conn); err != nil {
+		conn.Close()
+		return
+	}
+
+	p.pool.Put(conn)
+}
+
+type PoolConn struct {
+	*Snell
+	pool *Pool
+}
+
+func (pc *PoolConn) Read(b []byte) (int, error) {
+	// save old status of reply (it mutable by Read)
+	reply := pc.Snell.reply
+
+	n, err := pc.Snell.Read(b)
+	if err == shadowaead.ErrZeroChunk {
+		// if reply is false, it should be client halfclose.
+		// ignore error and read data again.
+		if !reply {
+			pc.Snell.reply = false
+			return pc.Snell.Read(b)
+		}
+	}
+	return n, err
+}
+
+func (pc *PoolConn) Write(b []byte) (int, error) {
+	return pc.Snell.Write(b)
+}
+
+func (pc *PoolConn) Close() error {
+	pc.pool.Put(pc.Snell)
+	return nil
+}
+
+func NewPool(factory func(context.Context) (*Snell, error)) *Pool {
+	p := pool.New(
+		func(ctx context.Context) (interface{}, error) {
+			return factory(ctx)
+		},
+		pool.WithAge(15000),
+		pool.WithSize(10),
+		pool.WithEvict(func(item interface{}) {
+			item.(*Snell).Close()
+		}),
+	)
+
+	return &Pool{p}
+}

component/snell/snell.go

@@ -10,14 +10,21 @@ import (
 	"sync"
 
 	"github.com/Dreamacro/go-shadowsocks2/shadowaead"
-	"golang.org/x/crypto/chacha20poly1305"
 )
 
 const (
-	CommandPing    byte = 0
-	CommandConnect byte = 1
+	Version1            = 1
+	Version2            = 2
+	DefaultSnellVersion = Version1
+)
+
+const (
+	CommandPing      byte = 0
+	CommandConnect   byte = 1
+	CommandConnectV2 byte = 5
 
 	CommandTunnel byte = 0
+	CommandPong   byte = 1
 	CommandError  byte = 2
 
 	Version byte = 1
@@ -25,6 +32,7 @@ const (
 
 var (
 	bufferPool = sync.Pool{New: func() interface{} { return &bytes.Buffer{} }}
+	endSignal  = []byte{}
 )
 
 type Snell struct {
@@ -46,7 +54,7 @@ func (s *Snell) Read(b []byte) (int, error) {
 	if s.buffer[0] == CommandTunnel {
 		return s.Conn.Read(b)
 	} else if s.buffer[0] != CommandError {
-		return 0, errors.New("Command not support")
+		return 0, errors.New("command not support")
 	}
 
 	// CommandError
@@ -70,12 +78,16 @@ func (s *Snell) Read(b []byte) (int, error) {
 	return 0, fmt.Errorf("server reported code: %d, message: %s", errcode, string(msg))
 }
 
-func WriteHeader(conn net.Conn, host string, port uint) error {
+func WriteHeader(conn net.Conn, host string, port uint, version int) error {
 	buf := bufferPool.Get().(*bytes.Buffer)
 	buf.Reset()
 	defer bufferPool.Put(buf)
 	buf.WriteByte(Version)
-	buf.WriteByte(CommandConnect)
+	if version == Version2 {
+		buf.WriteByte(CommandConnectV2)
+	} else {
+		buf.WriteByte(CommandConnect)
+	}
 
 	// clientID length & id
 	buf.WriteByte(0)
@@ -92,7 +104,24 @@ func WriteHeader(conn net.Conn, host string, port uint) error {
 	return nil
 }
 
-func StreamConn(conn net.Conn, psk []byte) net.Conn {
-	cipher := &snellCipher{psk, chacha20poly1305.New}
+// HalfClose works only on version2
+func HalfClose(conn net.Conn) error {
+	if _, err := conn.Write(endSignal); err != nil {
+		return err
+	}
+
+	if s, ok := conn.(*Snell); ok {
+		s.reply = false
+	}
+	return nil
+}
+
+func StreamConn(conn net.Conn, psk []byte, version int) *Snell {
+	var cipher shadowaead.Cipher
+	if version == Version2 {
+		cipher = NewAES128GCM(psk)
+	} else {
+		cipher = NewChacha20Poly1305(psk)
+	}
 	return &Snell{Conn: shadowaead.NewConn(conn, cipher)}
 }

component/ssr/obfs/tls12_ticket_auth.go

@@ -6,13 +6,13 @@ import (
 	"encoding/binary"
 	"fmt"
 	"io"
-	"log"
 	"math/rand"
 	"strings"
 	"time"
 
 	"github.com/Dreamacro/clash/common/pool"
 	"github.com/Dreamacro/clash/component/ssr/tools"
+	"github.com/Dreamacro/clash/log"
 )
 
 type tlsAuthData struct {
@@ -63,7 +63,7 @@ func (t *tls12Ticket) Decode(b []byte) ([]byte, bool, error) {
 			var h [5]byte
 			t.recvBuffer.Read(h[:])
 			if !bytes.Equal(h[:3], []byte{0x17, 0x3, 0x3}) {
-				log.Println("incorrect magic number", h[:3], ", 0x170303 is expected")
+				log.Warnln("incorrect magic number %x, 0x170303 is expected", h[:3])
 				return nil, false, errTLS12TicketAuthIncorrectMagicNumber
 			}
 			size := int(binary.BigEndian.Uint16(h[3:5]))
@@ -287,5 +287,4 @@ func packData(buffer *bytes.Buffer, suffix []byte) {
 	binary.BigEndian.PutUint16(d[3:5], uint16(len(suffix)&0xFFFF))
 	buffer.Write(d)
 	buffer.Write(suffix)
-	return
 }

component/ssr/protocol/auth_chain_a.go

@@ -282,7 +282,6 @@ func (a *authChain) packData(outData []byte, data []byte, randLength int) {
 	binary.LittleEndian.PutUint32(key[userKeyLen:], a.chunkID)
 	a.lastClientHash = a.hmac(key, outData[:outLength])
 	copy(outData[outLength:], a.lastClientHash[:2])
-	return
 }
 
 const authHeadLength = 4 + 8 + 4 + 16 + 4

component/vmess/aead.go

@@ -86,7 +86,7 @@ func (r *aeadReader) Read(b []byte) (int, error) {
 
 	size := int(binary.BigEndian.Uint16(r.sizeBuf))
 	if size > maxSize {
-		return 0, errors.New("Buffer is larger than standard")
+		return 0, errors.New("buffer is larger than standard")
 	}
 
 	buf := pool.Get(size)

component/vmess/chunk.go

@@ -47,7 +47,7 @@ func (cr *chunkReader) Read(b []byte) (int, error) {
 
 	size := int(binary.BigEndian.Uint16(cr.sizeBuf))
 	if size > maxSize {
-		return 0, errors.New("Buffer is larger than standard")
+		return 0, errors.New("buffer is larger than standard")
 	}
 
 	if len(b) >= size {

component/vmess/h2.go

@@ -0,0 +1,111 @@
+package vmess
+
+import (
+	"io"
+	"math/rand"
+	"net"
+	"net/http"
+	"net/url"
+
+	"golang.org/x/net/http2"
+)
+
+type h2Conn struct {
+	net.Conn
+	*http2.ClientConn
+	pwriter *io.PipeWriter
+	res     *http.Response
+	cfg     *H2Config
+}
+
+type H2Config struct {
+	Hosts []string
+	Path  string
+}
+
+func (hc *h2Conn) establishConn() error {
+	preader, pwriter := io.Pipe()
+
+	host := hc.cfg.Hosts[rand.Intn(len(hc.cfg.Hosts))]
+	path := hc.cfg.Path
+	// TODO: connect use VMess Host instead of H2 Host
+	req := http.Request{
+		Method: "PUT",
+		Host:   host,
+		URL: &url.URL{
+			Scheme: "https",
+			Host:   host,
+			Path:   path,
+		},
+		Proto:      "HTTP/2",
+		ProtoMajor: 2,
+		ProtoMinor: 0,
+		Body:       preader,
+		Header: map[string][]string{
+			"Accept-Encoding": {"identity"},
+		},
+	}
+
+	res, err := hc.ClientConn.RoundTrip(&req)
+	if err != nil {
+		return err
+	}
+
+	hc.pwriter = pwriter
+	hc.res = res
+
+	return nil
+}
+
+// Read implements net.Conn.Read()
+func (hc *h2Conn) Read(b []byte) (int, error) {
+	if hc.res != nil && !hc.res.Close {
+		n, err := hc.res.Body.Read(b)
+		return n, err
+	}
+
+	if err := hc.establishConn(); err != nil {
+		return 0, err
+	}
+	return hc.res.Body.Read(b)
+}
+
+// Write implements io.Writer.
+func (hc *h2Conn) Write(b []byte) (int, error) {
+	if hc.pwriter != nil {
+		return hc.pwriter.Write(b)
+	}
+
+	if err := hc.establishConn(); err != nil {
+		return 0, err
+	}
+	return hc.pwriter.Write(b)
+}
+
+func (hc *h2Conn) Close() error {
+	if err := hc.pwriter.Close(); err != nil {
+		return err
+	}
+	if err := hc.ClientConn.Shutdown(hc.res.Request.Context()); err != nil {
+		return err
+	}
+	if err := hc.Conn.Close(); err != nil {
+		return err
+	}
+	return nil
+}
+
+func StreamH2Conn(conn net.Conn, cfg *H2Config) (net.Conn, error) {
+	transport := &http2.Transport{}
+
+	cconn, err := transport.NewClientConn(conn)
+	if err != nil {
+		return nil, err
+	}
+
+	return &h2Conn{
+		Conn:       conn,
+		ClientConn: cconn,
+		cfg:        cfg,
+	}, nil
+}

component/vmess/tls.go

@@ -9,6 +9,7 @@ type TLSConfig struct {
 	Host           string
 	SkipCertVerify bool
 	SessionCache   tls.ClientSessionCache
+	NextProtos     []string
 }
 
 func StreamTLSConn(conn net.Conn, cfg *TLSConfig) (net.Conn, error) {
@@ -16,6 +17,7 @@ func StreamTLSConn(conn net.Conn, cfg *TLSConfig) (net.Conn, error) {
 		ServerName:         cfg.Host,
 		InsecureSkipVerify: cfg.SkipCertVerify,
 		ClientSessionCache: cfg.SessionCache,
+		NextProtos:         cfg.NextProtos,
 	}
 
 	tlsConn := tls.Client(conn, tlsConfig)

component/vmess/vmess.go

@@ -1,12 +1,10 @@
 package vmess
 
 import (
-	"crypto/tls"
 	"fmt"
 	"math/rand"
 	"net"
 	"runtime"
-	"sync"
 
 	"github.com/gofrs/uuid"
 )
@@ -37,11 +35,6 @@ var CipherMapping = map[string]byte{
 	"chacha20-poly1305": SecurityCHACHA20POLY1305,
 }
 
-var (
-	clientSessionCache tls.ClientSessionCache
-	once               sync.Once
-)
-
 // Command types
 const (
 	CommandTCP byte = 1
@@ -106,7 +99,7 @@ func NewClient(config Config) (*Client, error) {
 			security = SecurityAES128GCM
 		}
 	default:
-		return nil, fmt.Errorf("Unknown security type: %s", config.Security)
+		return nil, fmt.Errorf("unknown security type: %s", config.Security)
 	}
 
 	return &Client{

component/vmess/websocket.go

@@ -73,7 +73,7 @@ func (wsc *websocketConn) Close() error {
 		errors = append(errors, err.Error())
 	}
 	if len(errors) > 0 {
-		return fmt.Errorf("Failed to close connection: %s", strings.Join(errors, ","))
+		return fmt.Errorf("failed to close connection: %s", strings.Join(errors, ","))
 	}
 	return nil
 }
@@ -159,7 +159,7 @@ func StreamWebsocketConn(conn net.Conn, c *WebsocketConfig) (net.Conn, error) {
 		if resp != nil {
 			reason = resp.Status
 		}
-		return nil, fmt.Errorf("Dial %s error: %s", uri.Host, reason)
+		return nil, fmt.Errorf("dial %s error: %s", uri.Host, reason)
 	}
 
 	return &websocketConn{

config/config.go

@@ -69,6 +69,7 @@ type DNS struct {
 type FallbackFilter struct {
 	GeoIP  bool         `yaml:"geoip"`
 	IPCIDR []*net.IPNet `yaml:"ipcidr"`
+	Domain []string     `yaml:"domain"`
 }
 
 // Experimental config
@@ -103,6 +104,7 @@ type RawDNS struct {
 type RawFallbackFilter struct {
 	GeoIP  bool     `yaml:"geoip"`
 	IPCIDR []string `yaml:"ipcidr"`
+	Domain []string `yaml:"domain"`
 }
 
 type RawConfig struct {
@@ -264,11 +266,11 @@ func parseProxies(cfg *RawConfig) (proxies map[string]C.Proxy, providersMap map[
 	for idx, mapping := range proxiesConfig {
 		proxy, err := outbound.ParseProxy(mapping)
 		if err != nil {
-			return nil, nil, fmt.Errorf("Proxy %d: %w", idx, err)
+			return nil, nil, fmt.Errorf("proxy %d: %w", idx, err)
 		}
 
 		if _, exist := proxies[proxy.Name()]; exist {
-			return nil, nil, fmt.Errorf("Proxy %s is the duplicate name", proxy.Name())
+			return nil, nil, fmt.Errorf("proxy %s is the duplicate name", proxy.Name())
 		}
 		proxies[proxy.Name()] = proxy
 		proxyList = append(proxyList, proxy.Name())
@@ -278,7 +280,7 @@ func parseProxies(cfg *RawConfig) (proxies map[string]C.Proxy, providersMap map[
 	for idx, mapping := range groupsConfig {
 		groupName, existName := mapping["name"].(string)
 		if !existName {
-			return nil, nil, fmt.Errorf("ProxyGroup %d: missing name", idx)
+			return nil, nil, fmt.Errorf("proxy group %d: missing name", idx)
 		}
 		proxyList = append(proxyList, groupName)
 	}
@@ -313,12 +315,12 @@ func parseProxies(cfg *RawConfig) (proxies map[string]C.Proxy, providersMap map[
 	for idx, mapping := range groupsConfig {
 		group, err := outboundgroup.ParseProxyGroup(mapping, proxies, providersMap)
 		if err != nil {
-			return nil, nil, fmt.Errorf("ProxyGroup[%d]: %w", idx, err)
+			return nil, nil, fmt.Errorf("proxy group[%d]: %w", idx, err)
 		}
 
 		groupName := group.Name()
 		if _, exist := proxies[groupName]; exist {
-			return nil, nil, fmt.Errorf("ProxyGroup %s: the duplicate name", groupName)
+			return nil, nil, fmt.Errorf("proxy group %s: the duplicate name", groupName)
 		}
 
 		proxies[groupName] = outbound.NewProxy(group)
@@ -373,11 +375,11 @@ func parseRules(cfg *RawConfig, proxies map[string]C.Proxy) ([]C.Rule, error) {
 			target = rule[2]
 			params = rule[3:]
 		default:
-			return nil, fmt.Errorf("Rules[%d] [%s] error: format invalid", idx, line)
+			return nil, fmt.Errorf("rules[%d] [%s] error: format invalid", idx, line)
 		}
 
 		if _, ok := proxies[target]; !ok {
-			return nil, fmt.Errorf("Rules[%d] [%s] error: proxy [%s] not found", idx, line, target)
+			return nil, fmt.Errorf("rules[%d] [%s] error: proxy [%s] not found", idx, line, target)
 		}
 
 		rule = trimArr(rule)
@@ -389,7 +391,7 @@ func parseRules(cfg *RawConfig, proxies map[string]C.Proxy) ([]C.Rule, error) {
 				log.Warnln("Rules[%d] [%s] don't support current OS, skip", idx, line)
 				continue
 			}
-			return nil, fmt.Errorf("Rules[%d] [%s] error: %s", idx, line, parseErr.Error())
+			return nil, fmt.Errorf("rules[%d] [%s] error: %s", idx, line, parseErr.Error())
 		}
 
 		rules = append(rules, parsed)
@@ -403,7 +405,7 @@ func parseHosts(cfg *RawConfig) (*trie.DomainTrie, error) {
 
 	// add default hosts
 	if err := tree.Insert("localhost", net.IP{127, 0, 0, 1}); err != nil {
-		println(err.Error())
+		log.Errorln("insert localhost to host error: %s", err.Error())
 	}
 
 	if len(cfg.Hosts) != 0 {
@@ -499,7 +501,7 @@ func parseFallbackIPCIDR(ips []string) ([]*net.IPNet, error) {
 
 func parseDNS(cfg RawDNS, hosts *trie.DomainTrie) (*DNS, error) {
 	if cfg.Enable && len(cfg.NameServer) == 0 {
-		return nil, fmt.Errorf("If DNS configuration is turned on, NameServer cannot be empty")
+		return nil, fmt.Errorf("if DNS configuration is turned on, NameServer cannot be empty")
 	}
 
 	dnsCfg := &DNS{
@@ -561,6 +563,7 @@ func parseDNS(cfg RawDNS, hosts *trie.DomainTrie) (*DNS, error) {
 	if fallbackip, err := parseFallbackIPCIDR(cfg.FallbackFilter.IPCIDR); err == nil {
 		dnsCfg.FallbackFilter.IPCIDR = fallbackip
 	}
+	dnsCfg.FallbackFilter.Domain = cfg.FallbackFilter.Domain
 
 	if cfg.UseHosts {
 		dnsCfg.Hosts = hosts

config/initial.go

@@ -32,18 +32,18 @@ func initMMDB() error {
 	if _, err := os.Stat(C.Path.MMDB()); os.IsNotExist(err) {
 		log.Infoln("Can't find MMDB, start download")
 		if err := downloadMMDB(C.Path.MMDB()); err != nil {
-			return fmt.Errorf("Can't download MMDB: %s", err.Error())
+			return fmt.Errorf("can't download MMDB: %s", err.Error())
 		}
 	}
 
 	if !mmdb.Verify() {
 		log.Warnln("MMDB invalid, remove and download")
 		if err := os.Remove(C.Path.MMDB()); err != nil {
-			return fmt.Errorf("Can't remove invalid MMDB: %s", err.Error())
+			return fmt.Errorf("can't remove invalid MMDB: %s", err.Error())
 		}
 
 		if err := downloadMMDB(C.Path.MMDB()); err != nil {
-			return fmt.Errorf("Can't download MMDB: %s", err.Error())
+			return fmt.Errorf("can't download MMDB: %s", err.Error())
 		}
 	}
 
@@ -55,7 +55,7 @@ func Init(dir string) error {
 	// initial homedir
 	if _, err := os.Stat(dir); os.IsNotExist(err) {
 		if err := os.MkdirAll(dir, 0777); err != nil {
-			return fmt.Errorf("Can't create config directory %s: %s", dir, err.Error())
+			return fmt.Errorf("can't create config directory %s: %s", dir, err.Error())
 		}
 	}
 
@@ -64,7 +64,7 @@ func Init(dir string) error {
 		log.Infoln("Can't find config, create a initial config file")
 		f, err := os.OpenFile(C.Path.Config(), os.O_CREATE|os.O_WRONLY, 0644)
 		if err != nil {
-			return fmt.Errorf("Can't create file %s: %s", C.Path.Config(), err.Error())
+			return fmt.Errorf("can't create file %s: %s", C.Path.Config(), err.Error())
 		}
 		f.Write([]byte(`port: 7890`))
 		f.Close()
@@ -72,7 +72,7 @@ func Init(dir string) error {
 
 	// initial mmdb
 	if err := initMMDB(); err != nil {
-		return fmt.Errorf("Can't initial MMDB: %w", err)
+		return fmt.Errorf("can't initial MMDB: %w", err)
 	}
 	return nil
 }

config/utils.go

@@ -15,15 +15,6 @@ func trimArr(arr []string) (r []string) {
 	return
 }
 
-func or(pointers ...*int) *int {
-	for _, p := range pointers {
-		if p != nil {
-			return p
-		}
-	}
-	return pointers[len(pointers)-1]
-}
-
 // Check if ProxyGroups form DAG(Directed Acyclic Graph), and sort all ProxyGroups by dependency order.
 // Meanwhile, record the original index in the config file.
 // If loop is detected, return an error with location of loop.
@@ -153,5 +144,5 @@ func proxyGroupsDagSort(groupsConfig []map[string]interface{}) error {
 		loopElements = append(loopElements, name)
 		delete(graph, name)
 	}
-	return fmt.Errorf("Loop is detected in ProxyGroup, please check following ProxyGroups: %v", loopElements)
+	return fmt.Errorf("loop is detected in ProxyGroup, please check following ProxyGroups: %v", loopElements)
 }

dns/enhancer.go

@@ -0,0 +1,76 @@
+package dns
+
+import (
+	"net"
+
+	"github.com/Dreamacro/clash/common/cache"
+	"github.com/Dreamacro/clash/component/fakeip"
+)
+
+type ResolverEnhancer struct {
+	mode     EnhancedMode
+	fakePool *fakeip.Pool
+	mapping  *cache.LruCache
+}
+
+func (h *ResolverEnhancer) FakeIPEnabled() bool {
+	return h.mode == FAKEIP
+}
+
+func (h *ResolverEnhancer) MappingEnabled() bool {
+	return h.mode == FAKEIP || h.mode == MAPPING
+}
+
+func (h *ResolverEnhancer) IsFakeIP(ip net.IP) bool {
+	if !h.FakeIPEnabled() {
+		return false
+	}
+
+	if pool := h.fakePool; pool != nil {
+		return pool.Exist(ip)
+	}
+
+	return false
+}
+
+func (h *ResolverEnhancer) FindHostByIP(ip net.IP) (string, bool) {
+	if pool := h.fakePool; pool != nil {
+		if host, existed := pool.LookBack(ip); existed {
+			return host, true
+		}
+	}
+
+	if mapping := h.mapping; mapping != nil {
+		if host, existed := h.mapping.Get(ip.String()); existed {
+			return host.(string), true
+		}
+	}
+
+	return "", false
+}
+
+func (h *ResolverEnhancer) PatchFrom(o *ResolverEnhancer) {
+	if h.mapping != nil && o.mapping != nil {
+		o.mapping.CloneTo(h.mapping)
+	}
+
+	if h.fakePool != nil && o.fakePool != nil {
+		h.fakePool.PatchFrom(o.fakePool)
+	}
+}
+
+func NewEnhancer(cfg Config) *ResolverEnhancer {
+	var fakePool *fakeip.Pool
+	var mapping *cache.LruCache
+
+	if cfg.EnhancedMode != NORMAL {
+		fakePool = cfg.Pool
+		mapping = cache.NewLRUCache(cache.WithSize(4096), cache.WithStale(true))
+	}
+
+	return &ResolverEnhancer{
+		mode:     cfg.EnhancedMode,
+		fakePool: fakePool,
+		mapping:  mapping,
+	}
+}

dns/filters.go

@@ -4,9 +4,10 @@ import (
 	"net"
 
 	"github.com/Dreamacro/clash/component/mmdb"
+	"github.com/Dreamacro/clash/component/trie"
 )
 
-type fallbackFilter interface {
+type fallbackIPFilter interface {
 	Match(net.IP) bool
 }
 
@@ -24,3 +25,22 @@ type ipnetFilter struct {
 func (inf *ipnetFilter) Match(ip net.IP) bool {
 	return inf.ipnet.Contains(ip)
 }
+
+type fallbackDomainFilter interface {
+	Match(domain string) bool
+}
+type domainFilter struct {
+	tree *trie.DomainTrie
+}
+
+func NewDomainFilter(domains []string) *domainFilter {
+	df := domainFilter{tree: trie.New()}
+	for _, domain := range domains {
+		df.tree.Insert(domain, "")
+	}
+	return &df
+}
+
+func (df *domainFilter) Match(domain string) bool {
+	return df.tree.Search(domain) != nil
+}

dns/middleware.go

@@ -3,7 +3,9 @@ package dns
 import (
 	"net"
 	"strings"
+	"time"
 
+	"github.com/Dreamacro/clash/common/cache"
 	"github.com/Dreamacro/clash/component/fakeip"
 	"github.com/Dreamacro/clash/component/trie"
 	"github.com/Dreamacro/clash/log"
@@ -11,23 +13,21 @@ import (
 	D "github.com/miekg/dns"
 )
 
-type handler func(w D.ResponseWriter, r *D.Msg)
+type handler func(r *D.Msg) (*D.Msg, error)
 type middleware func(next handler) handler
 
 func withHosts(hosts *trie.DomainTrie) middleware {
 	return func(next handler) handler {
-		return func(w D.ResponseWriter, r *D.Msg) {
+		return func(r *D.Msg) (*D.Msg, error) {
 			q := r.Question[0]
 
 			if !isIPRequest(q) {
-				next(w, r)
-				return
+				return next(r)
 			}
 
 			record := hosts.Search(strings.TrimRight(q.Name, "."))
 			if record == nil {
-				next(w, r)
-				return
+				return next(r)
 			}
 
 			ip := record.Data.(net.IP)
@@ -46,25 +46,67 @@ func withHosts(hosts *trie.DomainTrie) middleware {
 
 				msg.Answer = []D.RR{rr}
 			} else {
-				next(w, r)
-				return
+				return next(r)
 			}
 
 			msg.SetRcode(r, D.RcodeSuccess)
 			msg.Authoritative = true
 			msg.RecursionAvailable = true
 
-			w.WriteMsg(msg)
-			return
+			return msg, nil
+		}
+	}
+}
+
+func withMapping(mapping *cache.LruCache) middleware {
+	return func(next handler) handler {
+		return func(r *D.Msg) (*D.Msg, error) {
+			q := r.Question[0]
+
+			if !isIPRequest(q) {
+				return next(r)
+			}
+
+			msg, err := next(r)
+			if err != nil {
+				return nil, err
+			}
+
+			host := strings.TrimRight(q.Name, ".")
+
+			for _, ans := range msg.Answer {
+				var ip net.IP
+				var ttl uint32
+
+				switch a := ans.(type) {
+				case *D.A:
+					ip = a.A
+					ttl = a.Hdr.Ttl
+				case *D.AAAA:
+					ip = a.AAAA
+					ttl = a.Hdr.Ttl
+				default:
+					continue
+				}
+
+				mapping.SetWithExpire(ip.String(), host, time.Now().Add(time.Second*time.Duration(ttl)))
+			}
+
+			return msg, nil
 		}
 	}
 }
 
 func withFakeIP(fakePool *fakeip.Pool) middleware {
 	return func(next handler) handler {
-		return func(w D.ResponseWriter, r *D.Msg) {
+		return func(r *D.Msg) (*D.Msg, error) {
 			q := r.Question[0]
 
+			host := strings.TrimRight(q.Name, ".")
+			if fakePool.LookupHost(host) {
+				return next(r)
+			}
+
 			if q.Qtype == D.TypeAAAA {
 				msg := &D.Msg{}
 				msg.Answer = []D.RR{}
@@ -73,17 +115,9 @@ func withFakeIP(fakePool *fakeip.Pool) middleware {
 				msg.Authoritative = true
 				msg.RecursionAvailable = true
 
-				w.WriteMsg(msg)
-				return
+				return msg, nil
 			} else if q.Qtype != D.TypeA {
-				next(w, r)
-				return
-			}
-
-			host := strings.TrimRight(q.Name, ".")
-			if fakePool.LookupHost(host) {
-				next(w, r)
-				return
+				return next(r)
 			}
 
 			rr := &D.A{}
@@ -98,14 +132,13 @@ func withFakeIP(fakePool *fakeip.Pool) middleware {
 			msg.Authoritative = true
 			msg.RecursionAvailable = true
 
-			w.WriteMsg(msg)
-			return
+			return msg, nil
 		}
 	}
 }
 
 func withResolver(resolver *Resolver) handler {
-	return func(w D.ResponseWriter, r *D.Msg) {
+	return func(r *D.Msg) (*D.Msg, error) {
 		q := r.Question[0]
 
 		// return a empty AAAA msg when ipv6 disabled
@@ -117,20 +150,18 @@ func withResolver(resolver *Resolver) handler {
 			msg.Authoritative = true
 			msg.RecursionAvailable = true
 
-			w.WriteMsg(msg)
-			return
+			return msg, nil
 		}
 
 		msg, err := resolver.Exchange(r)
 		if err != nil {
 			log.Debugln("[DNS Server] Exchange %s failed: %v", q.String(), err)
-			D.HandleFailed(w, r)
-			return
+			return msg, err
 		}
 		msg.SetRcode(r, msg.Rcode)
 		msg.Authoritative = true
-		w.WriteMsg(msg)
-		return
+
+		return msg, nil
 	}
 }
 
@@ -145,15 +176,19 @@ func compose(middlewares []middleware, endpoint handler) handler {
 	return h
 }
 
-func newHandler(resolver *Resolver) handler {
+func newHandler(resolver *Resolver, mapper *ResolverEnhancer) handler {
 	middlewares := []middleware{}
 
 	if resolver.hosts != nil {
 		middlewares = append(middlewares, withHosts(resolver.hosts))
 	}
 
-	if resolver.FakeIPEnabled() {
-		middlewares = append(middlewares, withFakeIP(resolver.pool))
+	if mapper.mode == FAKEIP {
+		middlewares = append(middlewares, withFakeIP(mapper.fakePool))
+	}
+
+	if mapper.mode != NORMAL {
+		middlewares = append(middlewares, withMapping(mapper.mapping))
 	}
 
 	return compose(middlewares, withResolver(resolver))

dns/resolver.go

@@ -35,16 +35,14 @@ type result struct {
 }
 
 type Resolver struct {
-	ipv6            bool
-	mapping         bool
-	fakeip          bool
-	hosts           *trie.DomainTrie
-	pool            *fakeip.Pool
-	main            []dnsClient
-	fallback        []dnsClient
-	fallbackFilters []fallbackFilter
-	group           singleflight.Group
-	lruCache        *cache.LruCache
+	ipv6                  bool
+	hosts                 *trie.DomainTrie
+	main                  []dnsClient
+	fallback              []dnsClient
+	fallbackDomainFilters []fallbackDomainFilter
+	fallbackIPFilters     []fallbackIPFilter
+	group                 singleflight.Group
+	lruCache              *cache.LruCache
 }
 
 // ResolveIP request with TypeA and TypeAAAA, priority return TypeA
@@ -82,8 +80,8 @@ func (r *Resolver) ResolveIPv6(host string) (ip net.IP, err error) {
 	return r.resolveIP(host, D.TypeAAAA)
 }
 
-func (r *Resolver) shouldFallback(ip net.IP) bool {
-	for _, filter := range r.fallbackFilters {
+func (r *Resolver) shouldIPFallback(ip net.IP) bool {
+	for _, filter := range r.fallbackIPFilters {
 		if filter.Match(ip) {
 			return true
 		}
@@ -106,7 +104,7 @@ func (r *Resolver) Exchange(m *D.Msg) (msg *D.Msg, err error) {
 			setMsgTTL(msg, uint32(1)) // Continue fetch
 			go r.exchangeWithoutCache(m)
 		} else {
-			setMsgTTL(msg, uint32(expireTime.Sub(time.Now()).Seconds()))
+			setMsgTTL(msg, uint32(time.Until(expireTime).Seconds()))
 		}
 		return
 	}
@@ -126,17 +124,11 @@ func (r *Resolver) exchangeWithoutCache(m *D.Msg) (msg *D.Msg, err error) {
 			msg := result.(*D.Msg)
 
 			putMsgToCache(r.lruCache, q.String(), msg)
-			if r.mapping || r.fakeip {
-				ips := r.msgToIP(msg)
-				for _, ip := range ips {
-					putMsgToCache(r.lruCache, ip.String(), msg)
-				}
-			}
 		}()
 
 		isIPReq := isIPRequest(q)
 		if isIPReq {
-			return r.fallbackExchange(m)
+			return r.ipExchange(m)
 		}
 
 		return r.batchExchange(r.main, m)
@@ -152,40 +144,6 @@ func (r *Resolver) exchangeWithoutCache(m *D.Msg) (msg *D.Msg, err error) {
 	return
 }
 
-// IPToHost return fake-ip or redir-host mapping host
-func (r *Resolver) IPToHost(ip net.IP) (string, bool) {
-	if r.fakeip {
-		record, existed := r.pool.LookBack(ip)
-		if existed {
-			return record, true
-		}
-	}
-
-	cache, _ := r.lruCache.Get(ip.String())
-	if cache == nil {
-		return "", false
-	}
-	fqdn := cache.(*D.Msg).Question[0].Name
-	return strings.TrimRight(fqdn, "."), true
-}
-
-func (r *Resolver) IsMapping() bool {
-	return r.mapping
-}
-
-// FakeIPEnabled returns if fake-ip is enabled
-func (r *Resolver) FakeIPEnabled() bool {
-	return r.fakeip
-}
-
-// IsFakeIP determine if given ip is a fake-ip
-func (r *Resolver) IsFakeIP(ip net.IP) bool {
-	if r.FakeIPEnabled() {
-		return r.pool.Exist(ip)
-	}
-	return false
-}
-
 func (r *Resolver) batchExchange(clients []dnsClient, m *D.Msg) (msg *D.Msg, err error) {
 	fast, ctx := picker.WithTimeout(context.Background(), time.Second*5)
 	for _, client := range clients {
@@ -203,7 +161,7 @@ func (r *Resolver) batchExchange(clients []dnsClient, m *D.Msg) (msg *D.Msg, err
 
 	elm := fast.Wait()
 	if elm == nil {
-		err := errors.New("All DNS requests failed")
+		err := errors.New("all DNS requests failed")
 		if fErr := fast.Error(); fErr != nil {
 			err = fmt.Errorf("%w, first error: %s", err, fErr.Error())
 		}
@@ -214,19 +172,49 @@ func (r *Resolver) batchExchange(clients []dnsClient, m *D.Msg) (msg *D.Msg, err
 	return
 }
 
-func (r *Resolver) fallbackExchange(m *D.Msg) (msg *D.Msg, err error) {
+func (r *Resolver) shouldOnlyQueryFallback(m *D.Msg) bool {
+	if r.fallback == nil || len(r.fallbackDomainFilters) == 0 {
+		return false
+	}
+
+	domain := r.msgToDomain(m)
+
+	if domain == "" {
+		return false
+	}
+
+	for _, df := range r.fallbackDomainFilters {
+		if df.Match(domain) {
+			return true
+		}
+	}
+
+	return false
+}
+
+func (r *Resolver) ipExchange(m *D.Msg) (msg *D.Msg, err error) {
+
+	onlyFallback := r.shouldOnlyQueryFallback(m)
+
+	if onlyFallback {
+		res := <-r.asyncExchange(r.fallback, m)
+		return res.Msg, res.Error
+	}
+
 	msgCh := r.asyncExchange(r.main, m)
-	if r.fallback == nil {
+
+	if r.fallback == nil { // directly return if no fallback servers are available
 		res := <-msgCh
 		msg, err = res.Msg, res.Error
 		return
 	}
+
 	fallbackMsg := r.asyncExchange(r.fallback, m)
 	res := <-msgCh
 	if res.Error == nil {
 		if ips := r.msgToIP(res.Msg); len(ips) != 0 {
-			if !r.shouldFallback(ips[0]) {
-				msg = res.Msg
+			if !r.shouldIPFallback(ips[0]) {
+				msg = res.Msg // no need to wait for fallback result
 				err = res.Error
 				return msg, err
 			}
@@ -284,6 +272,14 @@ func (r *Resolver) msgToIP(msg *D.Msg) []net.IP {
 	return ips
 }
 
+func (r *Resolver) msgToDomain(msg *D.Msg) string {
+	if len(msg.Question) > 0 {
+		return strings.TrimRight(msg.Question[0].Name, ".")
+	}
+
+	return ""
+}
+
 func (r *Resolver) asyncExchange(client []dnsClient, msg *D.Msg) <-chan *result {
 	ch := make(chan *result, 1)
 	go func() {
@@ -301,6 +297,7 @@ type NameServer struct {
 type FallbackFilter struct {
 	GeoIP  bool
 	IPCIDR []*net.IPNet
+	Domain []string
 }
 
 type Config struct {
@@ -313,7 +310,7 @@ type Config struct {
 	Hosts          *trie.DomainTrie
 }
 
-func New(config Config) *Resolver {
+func NewResolver(config Config) *Resolver {
 	defaultResolver := &Resolver{
 		main:     transform(config.Default, nil),
 		lruCache: cache.NewLRUCache(cache.WithSize(4096), cache.WithStale(true)),
@@ -323,9 +320,6 @@ func New(config Config) *Resolver {
 		ipv6:     config.IPv6,
 		main:     transform(config.Main, defaultResolver),
 		lruCache: cache.NewLRUCache(cache.WithSize(4096), cache.WithStale(true)),
-		mapping:  config.EnhancedMode == MAPPING,
-		fakeip:   config.EnhancedMode == FAKEIP,
-		pool:     config.Pool,
 		hosts:    config.Hosts,
 	}
 
@@ -333,14 +327,19 @@ func New(config Config) *Resolver {
 		r.fallback = transform(config.Fallback, defaultResolver)
 	}
 
-	fallbackFilters := []fallbackFilter{}
+	fallbackIPFilters := []fallbackIPFilter{}
 	if config.FallbackFilter.GeoIP {
-		fallbackFilters = append(fallbackFilters, &geoipFilter{})
+		fallbackIPFilters = append(fallbackIPFilters, &geoipFilter{})
 	}
 	for _, ipnet := range config.FallbackFilter.IPCIDR {
-		fallbackFilters = append(fallbackFilters, &ipnetFilter{ipnet: ipnet})
+		fallbackIPFilters = append(fallbackIPFilters, &ipnetFilter{ipnet: ipnet})
+	}
+	r.fallbackIPFilters = fallbackIPFilters
+
+	if len(config.FallbackFilter.Domain) != 0 {
+		fallbackDomainFilters := []fallbackDomainFilter{NewDomainFilter(config.FallbackFilter.Domain)}
+		r.fallbackDomainFilters = fallbackDomainFilters
 	}
-	r.fallbackFilters = fallbackFilters
 
 	return r
 }

dns/server.go

@@ -27,16 +27,22 @@ func (s *Server) ServeDNS(w D.ResponseWriter, r *D.Msg) {
 		return
 	}
 
-	s.handler(w, r)
+	msg, err := s.handler(r)
+	if err != nil {
+		D.HandleFailed(w, r)
+		return
+	}
+
+	w.WriteMsg(msg)
 }
 
 func (s *Server) setHandler(handler handler) {
 	s.handler = handler
 }
 
-func ReCreateServer(addr string, resolver *Resolver) error {
+func ReCreateServer(addr string, resolver *Resolver, mapper *ResolverEnhancer) error {
 	if addr == address && resolver != nil {
-		handler := newHandler(resolver)
+		handler := newHandler(resolver, mapper)
 		server.setHandler(handler)
 		return nil
 	}
@@ -68,7 +74,7 @@ func ReCreateServer(addr string, resolver *Resolver) error {
 	}
 
 	address = addr
-	handler := newHandler(resolver)
+	handler := newHandler(resolver, mapper)
 	server = &Server{handler: handler}
 	server.Server = &D.Server{Addr: addr, PacketConn: p, Handler: server}
 

go.mod

@@ -3,21 +3,21 @@ module github.com/Dreamacro/clash
 go 1.14
 
 require (
-	github.com/Dreamacro/go-shadowsocks2 v0.1.6-0.20200722122336-8e5c7db4f96a
+	github.com/Dreamacro/go-shadowsocks2 v0.1.6
 	github.com/eapache/queue v1.1.0 // indirect
 	github.com/go-chi/chi v4.1.2+incompatible
 	github.com/go-chi/cors v1.1.1
 	github.com/go-chi/render v1.0.1
 	github.com/gofrs/uuid v3.3.0+incompatible
 	github.com/gorilla/websocket v1.4.2
-	github.com/miekg/dns v1.1.29
+	github.com/miekg/dns v1.1.31
 	github.com/oschwald/geoip2-golang v1.4.0
 	github.com/sirupsen/logrus v1.6.0
 	github.com/stretchr/testify v1.6.1
-	golang.org/x/crypto v0.0.0-20200604202706-70a84ac30bf9
-	golang.org/x/net v0.0.0-20200602114024-627f9648deb9
-	golang.org/x/sync v0.0.0-20200317015054-43a5402ce75a
-	golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd
+	golang.org/x/crypto v0.0.0-20200728195943-123391ffb6de
+	golang.org/x/net v0.0.0-20200813134508-3edf25e44fcc
+	golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208
+	golang.org/x/sys v0.0.0-20200814200057-3d37ad5750ed
 	gopkg.in/eapache/channels.v1 v1.1.0
 	gopkg.in/yaml.v2 v2.3.0
 )

go.sum

@@ -1,5 +1,5 @@
-github.com/Dreamacro/go-shadowsocks2 v0.1.6-0.20200722122336-8e5c7db4f96a h1:JhQFrFOkCpRB8qsN6PrzHFzjy/8iQpFFk5cbOiplh6s=
-github.com/Dreamacro/go-shadowsocks2 v0.1.6-0.20200722122336-8e5c7db4f96a/go.mod h1:LSXCjyHesPY3pLjhwff1mQX72ItcBT/N2xNC685cYeU=
+github.com/Dreamacro/go-shadowsocks2 v0.1.6 h1:PysSf9sLT3Qn8jhlin5v7Rk68gOQG4K5BZFY1nxLGxI=
+github.com/Dreamacro/go-shadowsocks2 v0.1.6/go.mod h1:LSXCjyHesPY3pLjhwff1mQX72ItcBT/N2xNC685cYeU=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
@@ -17,8 +17,8 @@ github.com/gorilla/websocket v1.4.2 h1:+/TMaTYc4QFitKJxsQ7Yye35DkWvkdLcvGKqM+x0U
 github.com/gorilla/websocket v1.4.2/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/konsorten/go-windows-terminal-sequences v1.0.3 h1:CE8S1cTafDpPvMhIxNJKvHsGVBgn1xWYf1NbHQhywc8=
 github.com/konsorten/go-windows-terminal-sequences v1.0.3/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
-github.com/miekg/dns v1.1.29 h1:xHBEhR+t5RzcFJjBLJlax2daXOrTYtr9z4WdKEfWFzg=
-github.com/miekg/dns v1.1.29/go.mod h1:KNUDUusw/aVsxyTYZM1oqvCicbwhgbNgztCETuNZ7xM=
+github.com/miekg/dns v1.1.31 h1:sJFOl9BgwbYAWOGEwr61FU28pqsBNdpRBnhGXtO06Oo=
+github.com/miekg/dns v1.1.31/go.mod h1:KNUDUusw/aVsxyTYZM1oqvCicbwhgbNgztCETuNZ7xM=
 github.com/oschwald/geoip2-golang v1.4.0 h1:5RlrjCgRyIGDz/mBmPfnAF4h8k0IAcRv9PvrpOfz+Ug=
 github.com/oschwald/geoip2-golang v1.4.0/go.mod h1:8QwxJvRImBH+Zl6Aa6MaIcs5YdlZSTKtzmPGzQqi9ng=
 github.com/oschwald/maxminddb-golang v1.6.0 h1:KAJSjdHQ8Kv45nFIbtoLGrGWqHFajOIm7skTyz/+Dls=
@@ -27,7 +27,6 @@ github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZb
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/sirupsen/logrus v1.6.0 h1:UBcNElsrwanuuMsnGSlYmtmgbb23qDR5dG+6X6Oo89I=
 github.com/sirupsen/logrus v1.6.0/go.mod h1:7uNnSEd1DgxDLC74fIahvMZmmYsHGZGEOFrfsX/uA88=
-github.com/stretchr/objx v0.1.0 h1:4G4v2dO3VZwixGIRoQ5Lfboy6nUhCyYzaqnIAPPhYs4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
@@ -36,24 +35,27 @@ github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20191206172530-e9b2fee46413/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
-golang.org/x/crypto v0.0.0-20200604202706-70a84ac30bf9 h1:vEg9joUBmeBcK9iSJftGNf3coIG4HqZElCPehJsfAYM=
-golang.org/x/crypto v0.0.0-20200604202706-70a84ac30bf9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/crypto v0.0.0-20200728195943-123391ffb6de h1:ikNHVSjEfnvz6sxdSPCaPt572qowuyMDMJLLm3Db3ig=
+golang.org/x/crypto v0.0.0-20200728195943-123391ffb6de/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee/go.mod h1:QqPTAvyqsEbceGzBzNggFXnrqF1CaUcvgkdR5Ot7KZg=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20190923162816-aa69164e4478/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
-golang.org/x/net v0.0.0-20200602114024-627f9648deb9 h1:pNX+40auqi2JqRfOP1akLGtYcn15TUbkhwuCO3foqqM=
-golang.org/x/net v0.0.0-20200602114024-627f9648deb9/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
+golang.org/x/net v0.0.0-20200813134508-3edf25e44fcc h1:zK/HqS5bZxDptfPJNq8v7vJfXtkU7r9TLIoSr1bXaP4=
+golang.org/x/net v0.0.0-20200813134508-3edf25e44fcc/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.0.0-20200317015054-43a5402ce75a h1:WXEvlFVvvGxCJLG6REjsT03iWnKLEWinaScsxF2Vm2o=
-golang.org/x/sync v0.0.0-20200317015054-43a5402ce75a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208 h1:qwRHBd0NqMbJxfbotnDhm2ByMI1Shq4Y6oRJo21SGJA=
+golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190422165155-953cdadca894/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190924154521-2837fb4f24fe/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191224085550-c709ea063b76/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd h1:xhmwyvizuTgC2qz7ZlMluP20uW+C3Rm0FD/WLDX8884=
 golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200814200057-3d37ad5750ed h1:J22ig1FUekjjkmZUM7pTKixYm8DvrYsvrBZdunYeIuQ=
+golang.org/x/sys v0.0.0-20200814200057-3d37ad5750ed/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/tools v0.0.0-20191216052735-49a3e744a425/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

hub/executor/executor.go

@@ -34,7 +34,7 @@ func readConfig(path string) ([]byte, error) {
 	}
 
 	if len(data) == 0 {
-		return nil, fmt.Errorf("Configuration file %s is empty", path)
+		return nil, fmt.Errorf("configuration file %s is empty", path)
 	}
 
 	return data, err
@@ -101,13 +101,14 @@ func GetGeneral() *config.General {
 func updateExperimental(c *config.Config) {}
 
 func updateDNS(c *config.DNS) {
-	if c.Enable == false {
+	if !c.Enable {
 		resolver.DefaultResolver = nil
-		tunnel.SetResolver(nil)
-		dns.ReCreateServer("", nil)
+		resolver.DefaultHostMapper = nil
+		dns.ReCreateServer("", nil, nil)
 		return
 	}
-	r := dns.New(dns.Config{
+
+	cfg := dns.Config{
 		Main:         c.NameServer,
 		Fallback:     c.Fallback,
 		IPv6:         c.IPv6,
@@ -117,12 +118,23 @@ func updateDNS(c *config.DNS) {
 		FallbackFilter: dns.FallbackFilter{
 			GeoIP:  c.FallbackFilter.GeoIP,
 			IPCIDR: c.FallbackFilter.IPCIDR,
+			Domain: c.FallbackFilter.Domain,
 		},
 		Default: c.DefaultNameserver,
-	})
+	}
+
+	r := dns.NewResolver(cfg)
+	m := dns.NewEnhancer(cfg)
+
+	// reuse cache of old host mapper
+	if old := resolver.DefaultHostMapper; old != nil {
+		m.PatchFrom(old.(*dns.ResolverEnhancer))
+	}
+
 	resolver.DefaultResolver = r
-	tunnel.SetResolver(r)
-	if err := dns.ReCreateServer(c.Listen, r); err != nil {
+	resolver.DefaultHostMapper = m
+
+	if err := dns.ReCreateServer(c.Listen, r, m); err != nil {
 		log.Errorln("Start DNS server error: %s", err.Error())
 		return
 	}

log/log.go

@@ -64,7 +64,6 @@ func Subscribe() observable.Subscription {
 
 func UnSubscribe(sub observable.Subscription) {
 	source.UnSubscribe(sub)
-	return
 }
 
 func Level() LogLevel {

main.go

@@ -10,7 +10,6 @@ import (
 	"syscall"
 
 	"github.com/Dreamacro/clash/config"
-	"github.com/Dreamacro/clash/constant"
 	C "github.com/Dreamacro/clash/constant"
 	"github.com/Dreamacro/clash/hub"
 	"github.com/Dreamacro/clash/hub/executor"
@@ -76,10 +75,10 @@ func main() {
 	if testConfig {
 		if _, err := executor.Parse(); err != nil {
 			log.Errorln(err.Error())
-			fmt.Printf("configuration file %s test failed\n", constant.Path.Config())
+			fmt.Printf("configuration file %s test failed\n", C.Path.Config())
 			os.Exit(1)
 		}
-		fmt.Printf("configuration file %s test is successful\n", constant.Path.Config())
+		fmt.Printf("configuration file %s test is successful\n", C.Path.Config())
 		return
 	}
 

proxy/http/server.go

@@ -60,6 +60,7 @@ func (l *HttpListener) Address() string {
 func canActivate(loginStr string, authenticator auth.Authenticator, cache *cache.Cache) (ret bool) {
 	if result := cache.Get(loginStr); result != nil {
 		ret = result.(bool)
+		return
 	}
 	loginData, err := base64.StdEncoding.DecodeString(loginStr)
 	login := strings.Split(string(loginData), ":")
@@ -80,7 +81,7 @@ func HandleConn(conn net.Conn, cache *cache.Cache) {
 	authenticator := authStore.Authenticator()
 	if authenticator != nil {
 		if authStrings := strings.Split(request.Header.Get("Proxy-Authorization"), " "); len(authStrings) != 2 {
-			_, err = conn.Write([]byte("HTTP/1.1 407 Proxy Authentication Required\r\nProxy-Authenticate: Basic\r\n\r\n"))
+			conn.Write([]byte("HTTP/1.1 407 Proxy Authentication Required\r\nProxy-Authenticate: Basic\r\n\r\n"))
 			conn.Close()
 			return
 		} else if !canActivate(authStrings[1], authenticator, cache) {

proxy/listener.go

@@ -30,14 +30,8 @@ var (
 	httpMux  sync.Mutex
 	redirMux sync.Mutex
 	mixedMux sync.Mutex
-	tunMux   sync.Mutex
 )
 
-type listener interface {
-	Close()
-	Address() string
-}
-
 type Ports struct {
 	Port      int `json:"port"`
 	SocksPort int `json:"socks-port"`

proxy/redir/utils.go

@@ -34,5 +34,4 @@ func (c *packet) LocalAddr() net.Addr {
 
 func (c *packet) Drop() {
 	pool.Put(c.buf)
-	return
 }

proxy/socks/utils.go

@@ -34,5 +34,4 @@ func (c *packet) LocalAddr() net.Addr {
 
 func (c *packet) Drop() {
 	pool.Put(c.bufRef)
-	return
 }

rules/base.go

@@ -6,7 +6,6 @@ import (
 
 var (
 	errPayload            = errors.New("payload error")
-	errParams             = errors.New("params error")
 	ErrPlatformNotSupport = errors.New("not support on this platform")
 	ErrInvalidNetwork     = errors.New("invalid network")
 

rules/process_darwin.go

@@ -127,8 +127,8 @@ func getExecPathFromAddress(metadata *C.Metadata) (string, error) {
 		// rup8(sizeof(xtcpcb_n))
 		itemSize += 208
 	}
-	// skip the first and last xinpgen(24 bytes) block
-	for i := 24; i < len(buf)-24; i += itemSize {
+	// skip the first xinpgen(24 bytes) block
+	for i := 24; i+itemSize <= len(buf); i += itemSize {
 		// offset of xinpcb_n and xsocket_n
 		inp, so := i, i+104
 

rules/process_freebsd_amd64.go

@@ -8,6 +8,7 @@ import (
 	"path/filepath"
 	"strconv"
 	"strings"
+	"sync"
 	"syscall"
 	"unsafe"
 
@@ -17,7 +18,15 @@ import (
 )
 
 // store process name for when dealing with multiple PROCESS-NAME rules
-var processCache = cache.NewLRUCache(cache.WithAge(2), cache.WithSize(64))
+var (
+	processCache = cache.NewLRUCache(cache.WithAge(2), cache.WithSize(64))
+	errNotFound  = errors.New("process not found")
+	matchMeta    = func(p *Process, m *C.Metadata) bool { return false }
+
+	defaultSearcher *searcher
+
+	once sync.Once
+)
 
 type Process struct {
 	adapter string
@@ -28,7 +37,7 @@ func (ps *Process) RuleType() C.RuleType {
 	return C.Process
 }
 
-func (ps *Process) Match(metadata *C.Metadata) bool {
+func match(ps *Process, metadata *C.Metadata) bool {
 	key := fmt.Sprintf("%s:%s:%s", metadata.NetWork.String(), metadata.SrcIP.String(), metadata.SrcPort)
 	cached, hit := processCache.Get(key)
 	if !hit {
@@ -45,6 +54,10 @@ func (ps *Process) Match(metadata *C.Metadata) bool {
 	return strings.EqualFold(cached.(string), ps.process)
 }
 
+func (ps *Process) Match(metadata *C.Metadata) bool {
+	return matchMeta(ps, metadata)
+}
+
 func (p *Process) Adapter() string {
 	return p.adapter
 }
@@ -58,6 +71,15 @@ func (p *Process) ShouldResolveIP() bool {
 }
 
 func NewProcess(process string, adapter string) (*Process, error) {
+	once.Do(func() {
+		err := initSearcher()
+		if err != nil {
+			log.Errorln("Initialize PROCESS-NAME failed: %s", err.Error())
+			log.Warnln("All PROCESS-NAME rules will be skipped")
+			return
+		}
+		matchMeta = match
+	})
 	return &Process{
 		adapter: adapter,
 		process: process,
@@ -85,28 +107,6 @@ func getExecPathFromPID(pid uint32) (string, error) {
 	return filepath.Base(string(buf[:size-1])), nil
 }
 
-func searchSocketPid(socket uint64) (uint32, error) {
-	value, err := syscall.Sysctl("kern.file")
-	if err != nil {
-		return 0, err
-	}
-
-	buf := []byte(value)
-
-	// struct xfile
-	itemSize := 128
-	for i := 0; i < len(buf); i += itemSize {
-		// xfile.xf_data
-		data := binary.BigEndian.Uint64(buf[i+56 : i+64])
-		if data == socket {
-			// xfile.xf_pid
-			pid := readNativeUint32(buf[i+8 : i+12])
-			return pid, nil
-		}
-	}
-	return 0, errors.New("pid not found")
-}
-
 func getExecPathFromAddress(metadata *C.Metadata) (string, error) {
 	ip := metadata.SrcIP
 	port, err := strconv.Atoi(metadata.SrcPort)
@@ -115,25 +115,18 @@ func getExecPathFromAddress(metadata *C.Metadata) (string, error) {
 	}
 
 	var spath string
-	var itemSize int
-	var inpOffset int
+	var isTCP bool
 	switch metadata.NetWork {
 	case C.TCP:
 		spath = "net.inet.tcp.pcblist"
-		// struct xtcpcb
-		itemSize = 744
-		inpOffset = 8
+		isTCP = true
 	case C.UDP:
 		spath = "net.inet.udp.pcblist"
-		// struct xinpcb
-		itemSize = 400
-		inpOffset = 0
+		isTCP = false
 	default:
 		return "", ErrInvalidNetwork
 	}
 
-	isIPv4 := ip.To4() != nil
-
 	value, err := syscall.Sysctl(spath)
 	if err != nil {
 		return "", err
@@ -141,27 +134,73 @@ func getExecPathFromAddress(metadata *C.Metadata) (string, error) {
 
 	buf := []byte(value)
 
-	// skip the first and last xinpgen(64 bytes) block
-	for i := 64; i < len(buf)-64; i += itemSize {
+	pid, err := defaultSearcher.Search(buf, ip, uint16(port), isTCP)
+	if err != nil {
+		return "", err
+	}
+
+	return getExecPathFromPID(pid)
+}
+
+func readNativeUint32(b []byte) uint32 {
+	return *(*uint32)(unsafe.Pointer(&b[0]))
+}
+
+type searcher struct {
+	// sizeof(struct xinpgen)
+	headSize int
+	// sizeof(struct xtcpcb)
+	tcpItemSize int
+	// sizeof(struct xinpcb)
+	udpItemSize  int
+	udpInpOffset int
+	port         int
+	ip           int
+	vflag        int
+	socket       int
+
+	// sizeof(struct xfile)
+	fileItemSize int
+	data         int
+	pid          int
+}
+
+func (s *searcher) Search(buf []byte, ip net.IP, port uint16, isTCP bool) (uint32, error) {
+	var itemSize int
+	var inpOffset int
+
+	if isTCP {
+		// struct xtcpcb
+		itemSize = s.tcpItemSize
+		inpOffset = 8
+	} else {
+		// struct xinpcb
+		itemSize = s.udpItemSize
+		inpOffset = s.udpInpOffset
+	}
+
+	isIPv4 := ip.To4() != nil
+	// skip the first xinpgen block
+	for i := s.headSize; i+itemSize <= len(buf); i += itemSize {
 		inp := i + inpOffset
 
-		srcPort := binary.BigEndian.Uint16(buf[inp+254 : inp+256])
+		srcPort := binary.BigEndian.Uint16(buf[inp+s.port : inp+s.port+2])
 
-		if uint16(port) != srcPort {
+		if port != srcPort {
 			continue
 		}
 
 		// xinpcb.inp_vflag
-		flag := buf[inp+392]
+		flag := buf[inp+s.vflag]
 
 		var srcIP net.IP
 		switch {
 		case flag&0x1 > 0 && isIPv4:
 			// ipv4
-			srcIP = net.IP(buf[inp+284 : inp+288])
+			srcIP = net.IP(buf[inp+s.ip : inp+s.ip+4])
 		case flag&0x2 > 0 && !isIPv4:
 			// ipv6
-			srcIP = net.IP(buf[inp+272 : inp+288])
+			srcIP = net.IP(buf[inp+s.ip-12 : inp+s.ip+4])
 		default:
 			continue
 		}
@@ -171,17 +210,85 @@ func getExecPathFromAddress(metadata *C.Metadata) (string, error) {
 		}
 
 		// xsocket.xso_so, interpreted as big endian anyway since it's only used for comparison
-		socket := binary.BigEndian.Uint64(buf[inp+16 : inp+24])
-		pid, err := searchSocketPid(socket)
-		if err != nil {
-			return "", err
-		}
-		return getExecPathFromPID(pid)
+		socket := binary.BigEndian.Uint64(buf[inp+s.socket : inp+s.socket+8])
+		return s.searchSocketPid(socket)
+	}
+	return 0, errNotFound
+}
+
+func (s *searcher) searchSocketPid(socket uint64) (uint32, error) {
+	value, err := syscall.Sysctl("kern.file")
+	if err != nil {
+		return 0, err
 	}
 
-	return "", errors.New("process not found")
+	buf := []byte(value)
+
+	// struct xfile
+	itemSize := s.fileItemSize
+	for i := 0; i+itemSize <= len(buf); i += itemSize {
+		// xfile.xf_data
+		data := binary.BigEndian.Uint64(buf[i+s.data : i+s.data+8])
+		if data == socket {
+			// xfile.xf_pid
+			pid := readNativeUint32(buf[i+s.pid : i+s.pid+4])
+			return pid, nil
+		}
+	}
+	return 0, errNotFound
 }
 
-func readNativeUint32(b []byte) uint32 {
-	return *(*uint32)(unsafe.Pointer(&b[0]))
+func newSearcher(major int) *searcher {
+	var s *searcher = nil
+	switch major {
+	case 11:
+		s = &searcher{
+			headSize:     32,
+			tcpItemSize:  1304,
+			udpItemSize:  632,
+			port:         198,
+			ip:           228,
+			vflag:        116,
+			socket:       88,
+			fileItemSize: 80,
+			data:         56,
+			pid:          8,
+			udpInpOffset: 8,
+		}
+	case 12:
+		s = &searcher{
+			headSize:     64,
+			tcpItemSize:  744,
+			udpItemSize:  400,
+			port:         254,
+			ip:           284,
+			vflag:        392,
+			socket:       16,
+			fileItemSize: 128,
+			data:         56,
+			pid:          8,
+		}
+	}
+	return s
+}
+
+func initSearcher() error {
+	osRelease, err := syscall.Sysctl("kern.osrelease")
+	if err != nil {
+		return err
+	}
+
+	dot := strings.Index(osRelease, ".")
+	if dot != -1 {
+		osRelease = osRelease[:dot]
+	}
+	major, err := strconv.Atoi(osRelease)
+	if err != nil {
+		return err
+	}
+	defaultSearcher = newSearcher(major)
+	if defaultSearcher == nil {
+		return fmt.Errorf("unsupported freebsd version %d", major)
+	}
+	return nil
 }

rules/process_linux.go

@@ -257,7 +257,7 @@ func resolveProcessNameByProcSearch(inode, uid int) (string, error) {
 				continue
 			}
 
-			if bytes.Compare(buffer[:n], socket) == 0 {
+			if bytes.Equal(buffer[:n], socket) {
 				cmdline, err := ioutil.ReadFile(path.Join(processPath, "cmdline"))
 				if err != nil {
 					return "", err

tunnel/connection.go

@@ -9,14 +9,13 @@ import (
 	"strings"
 	"time"
 
-	adapters "github.com/Dreamacro/clash/adapters/inbound"
+	"github.com/Dreamacro/clash/adapters/inbound"
+	"github.com/Dreamacro/clash/common/pool"
 	"github.com/Dreamacro/clash/component/resolver"
 	C "github.com/Dreamacro/clash/constant"
-
-	"github.com/Dreamacro/clash/common/pool"
 )
 
-func handleHTTP(request *adapters.HTTPAdapter, outbound net.Conn) {
+func handleHTTP(request *inbound.HTTPAdapter, outbound net.Conn) {
 	req := request.R
 	host := req.Host
 
@@ -28,7 +27,7 @@ func handleHTTP(request *adapters.HTTPAdapter, outbound net.Conn) {
 
 		req.Header.Set("Connection", "close")
 		req.RequestURI = ""
-		adapters.RemoveHopByHopHeaders(req.Header)
+		inbound.RemoveHopByHopHeaders(req.Header)
 		err := req.Write(outbound)
 		if err != nil {
 			break
@@ -39,7 +38,7 @@ func handleHTTP(request *adapters.HTTPAdapter, outbound net.Conn) {
 		if err != nil {
 			break
 		}
-		adapters.RemoveHopByHopHeaders(resp.Header)
+		inbound.RemoveHopByHopHeaders(resp.Header)
 
 		if resp.StatusCode == http.StatusContinue {
 			err = resp.Write(request)
@@ -121,14 +120,14 @@ func handleUDPToLocal(packet C.UDPPacket, pc net.PacketConn, key string, fAddr n
 			from = fAddr
 		}
 
-		n, err = packet.WriteBack(buf[:n], from)
+		_, err = packet.WriteBack(buf[:n], from)
 		if err != nil {
 			return
 		}
 	}
 }
 
-func handleSocket(request *adapters.SocketAdapter, outbound net.Conn) {
+func handleSocket(request C.ServerAdapter, outbound net.Conn) {
 	relay(request, outbound)
 }
 

tunnel/manager.go

@@ -2,23 +2,20 @@ package tunnel
 
 import (
 	"sync"
+	"sync/atomic"
 	"time"
 )
 
 var DefaultManager *Manager
 
 func init() {
-	DefaultManager = &Manager{
-		upload:   make(chan int64),
-		download: make(chan int64),
-	}
-	DefaultManager.handle()
+	DefaultManager = &Manager{}
+
+	go DefaultManager.handle()
 }
 
 type Manager struct {
 	connections   sync.Map
-	upload        chan int64
-	download      chan int64
 	uploadTemp    int64
 	downloadTemp  int64
 	uploadBlip    int64
@@ -35,16 +32,18 @@ func (m *Manager) Leave(c tracker) {
 	m.connections.Delete(c.ID())
 }
 
-func (m *Manager) Upload() chan<- int64 {
-	return m.upload
+func (m *Manager) PushUploaded(size int64) {
+	atomic.AddInt64(&m.uploadTemp, size)
+	atomic.AddInt64(&m.uploadTotal, size)
 }
 
-func (m *Manager) Download() chan<- int64 {
-	return m.download
+func (m *Manager) PushDownloaded(size int64) {
+	atomic.AddInt64(&m.downloadTemp, size)
+	atomic.AddInt64(&m.downloadTotal, size)
 }
 
 func (m *Manager) Now() (up int64, down int64) {
-	return m.uploadBlip, m.downloadBlip
+	return atomic.LoadInt64(&m.uploadBlip), atomic.LoadInt64(&m.downloadBlip)
 }
 
 func (m *Manager) Snapshot() *Snapshot {
@@ -55,8 +54,8 @@ func (m *Manager) Snapshot() *Snapshot {
 	})
 
 	return &Snapshot{
-		UploadTotal:   m.uploadTotal,
-		DownloadTotal: m.downloadTotal,
+		UploadTotal:   atomic.LoadInt64(&m.uploadTotal),
+		DownloadTotal: atomic.LoadInt64(&m.downloadTotal),
 		Connections:   connections,
 	}
 }
@@ -71,21 +70,13 @@ func (m *Manager) ResetStatistic() {
 }
 
 func (m *Manager) handle() {
-	go m.handleCh(m.upload, &m.uploadTemp, &m.uploadBlip, &m.uploadTotal)
-	go m.handleCh(m.download, &m.downloadTemp, &m.downloadBlip, &m.downloadTotal)
-}
-
-func (m *Manager) handleCh(ch <-chan int64, temp *int64, blip *int64, total *int64) {
 	ticker := time.NewTicker(time.Second)
-	for {
-		select {
-		case n := <-ch:
-			*temp += n
-			*total += n
-		case <-ticker.C:
-			*blip = *temp
-			*temp = 0
-		}
+
+	for range ticker.C {
+		atomic.StoreInt64(&m.uploadBlip, atomic.LoadInt64(&m.uploadTemp))
+		atomic.StoreInt64(&m.uploadTemp, 0)
+		atomic.StoreInt64(&m.downloadBlip, atomic.LoadInt64(&m.downloadTemp))
+		atomic.StoreInt64(&m.downloadTemp, 0)
 	}
 }
 

tunnel/tracker.go

@@ -37,7 +37,7 @@ func (tt *tcpTracker) ID() string {
 func (tt *tcpTracker) Read(b []byte) (int, error) {
 	n, err := tt.Conn.Read(b)
 	download := int64(n)
-	tt.manager.Download() <- download
+	tt.manager.PushDownloaded(download)
 	tt.DownloadTotal += download
 	return n, err
 }
@@ -45,7 +45,7 @@ func (tt *tcpTracker) Read(b []byte) (int, error) {
 func (tt *tcpTracker) Write(b []byte) (int, error) {
 	n, err := tt.Conn.Write(b)
 	upload := int64(n)
-	tt.manager.Upload() <- upload
+	tt.manager.PushUploaded(upload)
 	tt.UploadTotal += upload
 	return n, err
 }
@@ -92,7 +92,7 @@ func (ut *udpTracker) ID() string {
 func (ut *udpTracker) ReadFrom(b []byte) (int, net.Addr, error) {
 	n, addr, err := ut.PacketConn.ReadFrom(b)
 	download := int64(n)
-	ut.manager.Download() <- download
+	ut.manager.PushDownloaded(download)
 	ut.DownloadTotal += download
 	return n, addr, err
 }
@@ -100,7 +100,7 @@ func (ut *udpTracker) ReadFrom(b []byte) (int, net.Addr, error) {
 func (ut *udpTracker) WriteTo(b []byte, addr net.Addr) (int, error) {
 	n, err := ut.PacketConn.WriteTo(b, addr)
 	upload := int64(n)
-	ut.manager.Upload() <- upload
+	ut.manager.PushUploaded(upload)
 	ut.UploadTotal += upload
 	return n, err
 }

tunnel/tunnel.go

@@ -12,21 +12,19 @@ import (
 	"github.com/Dreamacro/clash/component/nat"
 	"github.com/Dreamacro/clash/component/resolver"
 	C "github.com/Dreamacro/clash/constant"
-	"github.com/Dreamacro/clash/dns"
 	"github.com/Dreamacro/clash/log"
 
 	channels "gopkg.in/eapache/channels.v1"
 )
 
 var (
-	tcpQueue     = channels.NewInfiniteChannel()
-	udpQueue     = channels.NewInfiniteChannel()
-	natTable     = nat.New()
-	rules        []C.Rule
-	proxies      = make(map[string]C.Proxy)
-	providers    map[string]provider.ProxyProvider
-	configMux    sync.RWMutex
-	enhancedMode *dns.Resolver
+	tcpQueue  = channels.NewInfiniteChannel()
+	udpQueue  = channels.NewInfiniteChannel()
+	natTable  = nat.New()
+	rules     []C.Rule
+	proxies   = make(map[string]C.Proxy)
+	providers map[string]provider.ProxyProvider
+	configMux sync.RWMutex
 
 	// Outbound Rule
 	mode = Rule
@@ -89,11 +87,6 @@ func SetMode(m TunnelMode) {
 	mode = m
 }
 
-// SetResolver set custom dns resolver for enhanced mode
-func SetResolver(r *dns.Resolver) {
-	enhancedMode = r
-}
-
 // processUDP starts a loop to handle udp packet
 func processUDP() {
 	queue := udpQueue.Out()
@@ -120,7 +113,7 @@ func process() {
 }
 
 func needLookupIP(metadata *C.Metadata) bool {
-	return enhancedMode != nil && (enhancedMode.IsMapping() || enhancedMode.FakeIPEnabled()) && metadata.Host == "" && metadata.DstIP != nil
+	return resolver.MappingEnabled() && metadata.Host == "" && metadata.DstIP != nil
 }
 
 func preHandleMetadata(metadata *C.Metadata) error {
@@ -131,17 +124,17 @@ func preHandleMetadata(metadata *C.Metadata) error {
 
 	// preprocess enhanced-mode metadata
 	if needLookupIP(metadata) {
-		host, exist := enhancedMode.IPToHost(metadata.DstIP)
+		host, exist := resolver.FindHostByIP(metadata.DstIP)
 		if exist {
 			metadata.Host = host
 			metadata.AddrType = C.AtypDomainName
-			if enhancedMode.FakeIPEnabled() {
+			if resolver.FakeIPEnabled() {
 				metadata.DstIP = nil
 			} else if node := resolver.DefaultHosts.Search(host); node != nil {
 				// redir-host should lookup the hosts
 				metadata.DstIP = node.Data.(net.IP)
 			}
-		} else if enhancedMode.IsFakeIP(metadata.DstIP) {
+		} else if resolver.IsFakeIP(metadata.DstIP) {
 			return fmt.Errorf("fake DNS record %s missing", metadata.DstIP)
 		}
 	}
@@ -177,7 +170,7 @@ func handleUDPConn(packet *inbound.PacketAdapter) {
 
 	// make a fAddr if requset ip is fakeip
 	var fAddr net.Addr
-	if enhancedMode != nil && enhancedMode.IsFakeIP(metadata.DstIP) {
+	if resolver.IsFakeIP(metadata.DstIP) {
 		fAddr = metadata.UDPAddr()
 	}