add tun/tap

cmd/gost/norm.go

@@ -64,7 +64,8 @@ func normService(svc *config.ServiceConfig) {
 		}
 		if handler != "relay" {
 			if listener == "tcp" || listener == "udp" ||
-				listener == "rtcp" || listener == "rudp" {
+				listener == "rtcp" || listener == "rudp" ||
+				listener == "tun" || listener == "tap" {
 				handler = listener
 			} else {
 				handler = "tcp"

cmd/gost/register.go

@@ -44,6 +44,8 @@ import (
 	_ "github.com/go-gost/gost/pkg/handler/socks/v5"
 	_ "github.com/go-gost/gost/pkg/handler/ss"
 	_ "github.com/go-gost/gost/pkg/handler/ss/udp"
+	_ "github.com/go-gost/gost/pkg/handler/tap"
+	_ "github.com/go-gost/gost/pkg/handler/tun"
 
 	// Register listeners
 	_ "github.com/go-gost/gost/pkg/listener/ftcp"
@@ -57,6 +59,7 @@ import (
 	_ "github.com/go-gost/gost/pkg/listener/rtcp"
 	_ "github.com/go-gost/gost/pkg/listener/rudp"
 	_ "github.com/go-gost/gost/pkg/listener/ssh"
+	_ "github.com/go-gost/gost/pkg/listener/tap"
 	_ "github.com/go-gost/gost/pkg/listener/tcp"
 	_ "github.com/go-gost/gost/pkg/listener/tls"
 	_ "github.com/go-gost/gost/pkg/listener/tls/mux"

pkg/connector/http/metadata.go

@@ -22,9 +22,9 @@ func (c *httpConnector) parseMetadata(md mdata.Metadata) (err error) {
 		header         = "header"
 	)
 
-	c.md.connectTimeout = md.GetDuration(connectTimeout)
+	c.md.connectTimeout = mdata.GetDuration(md, connectTimeout)
 
-	if v := md.GetString(user); v != "" {
+	if v := mdata.GetString(md, user); v != "" {
 		ss := strings.SplitN(v, ":", 2)
 		if len(ss) == 1 {
 			c.md.User = url.User(ss[0])

pkg/connector/http2/metadata.go

@@ -5,7 +5,7 @@ import (
 	"strings"
 	"time"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 const (
@@ -18,20 +18,20 @@ type metadata struct {
 	User           *url.Userinfo
 }
 
-func (c *http2Connector) parseMetadata(md md.Metadata) (err error) {
+func (c *http2Connector) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		connectTimeout = "timeout"
 		userAgent      = "userAgent"
 		user           = "user"
 	)
 
-	c.md.connectTimeout = md.GetDuration(connectTimeout)
+	c.md.connectTimeout = mdata.GetDuration(md, connectTimeout)
-	c.md.UserAgent, _ = md.Get(userAgent).(string)
+	c.md.UserAgent = mdata.GetString(md, userAgent)
 	if c.md.UserAgent == "" {
 		c.md.UserAgent = defaultUserAgent
 	}
 
-	if v := md.GetString(user); v != "" {
+	if v := mdata.GetString(md, user); v != "" {
 		ss := strings.SplitN(v, ":", 2)
 		if len(ss) == 1 {
 			c.md.User = url.User(ss[0])

pkg/connector/relay/metadata.go

@@ -5,7 +5,7 @@ import (
 	"strings"
 	"time"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -14,14 +14,14 @@ type metadata struct {
 	noDelay        bool
 }
 
-func (c *relayConnector) parseMetadata(md md.Metadata) (err error) {
+func (c *relayConnector) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		user           = "user"
 		connectTimeout = "connectTimeout"
 		noDelay        = "nodelay"
 	)
 
-	if v := md.GetString(user); v != "" {
+	if v := mdata.GetString(md, user); v != "" {
 		ss := strings.SplitN(v, ":", 2)
 		if len(ss) == 1 {
 			c.md.user = url.User(ss[0])
@@ -29,8 +29,8 @@ func (c *relayConnector) parseMetadata(md md.Metadata) (err error) {
 			c.md.user = url.UserPassword(ss[0], ss[1])
 		}
 	}
-	c.md.connectTimeout = md.GetDuration(connectTimeout)
+	c.md.connectTimeout = mdata.GetDuration(md, connectTimeout)
-	c.md.noDelay = md.GetBool(noDelay)
+	c.md.noDelay = mdata.GetBool(md, noDelay)
 
 	return
 }

pkg/connector/sni/metadata.go

@@ -3,7 +3,7 @@ package sni
 import (
 	"time"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -11,14 +11,14 @@ type metadata struct {
 	connectTimeout time.Duration
 }
 
-func (c *sniConnector) parseMetadata(md md.Metadata) (err error) {
+func (c *sniConnector) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		host           = "host"
 		connectTimeout = "timeout"
 	)
 
-	c.md.host = md.GetString(host)
+	c.md.host = mdata.GetString(md, host)
-	c.md.connectTimeout = md.GetDuration(connectTimeout)
+	c.md.connectTimeout = mdata.GetDuration(md, connectTimeout)
 
 	return
 }

pkg/connector/socks/v4/metadata.go

@@ -4,7 +4,7 @@ import (
 	"net/url"
 	"time"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -13,18 +13,18 @@ type metadata struct {
 	disable4a      bool
 }
 
-func (c *socks4Connector) parseMetadata(md md.Metadata) (err error) {
+func (c *socks4Connector) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		connectTimeout = "timeout"
 		user           = "user"
 		disable4a      = "disable4a"
 	)
 
-	if v := md.GetString(user); v != "" {
+	if v := mdata.GetString(md, user); v != "" {
 		c.md.User = url.User(v)
 	}
-	c.md.connectTimeout = md.GetDuration(connectTimeout)
+	c.md.connectTimeout = mdata.GetDuration(md, connectTimeout)
-	c.md.disable4a = md.GetBool(disable4a)
+	c.md.disable4a = mdata.GetBool(md, disable4a)
 
 	return
 }

pkg/connector/socks/v5/metadata.go

@@ -6,7 +6,7 @@ import (
 	"strings"
 	"time"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -16,14 +16,14 @@ type metadata struct {
 	noTLS          bool
 }
 
-func (c *socks5Connector) parseMetadata(md md.Metadata) (err error) {
+func (c *socks5Connector) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		connectTimeout = "timeout"
 		user           = "user"
 		noTLS          = "notls"
 	)
 
-	if v := md.GetString(user); v != "" {
+	if v := mdata.GetString(md, user); v != "" {
 		ss := strings.SplitN(v, ":", 2)
 		if len(ss) == 1 {
 			c.md.User = url.User(ss[0])
@@ -32,8 +32,8 @@ func (c *socks5Connector) parseMetadata(md md.Metadata) (err error) {
 		}
 	}
 
-	c.md.connectTimeout = md.GetDuration(connectTimeout)
+	c.md.connectTimeout = mdata.GetDuration(md, connectTimeout)
-	c.md.noTLS = md.GetBool(noTLS)
+	c.md.noTLS = mdata.GetBool(md, noTLS)
 
 	return
 }

pkg/connector/ss/metadata.go

@@ -5,7 +5,7 @@ import (
 	"time"
 
 	"github.com/go-gost/gost/pkg/common/util/ss"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 	"github.com/shadowsocks/go-shadowsocks2/core"
 )
 
@@ -15,7 +15,7 @@ type metadata struct {
 	noDelay        bool
 }
 
-func (c *ssConnector) parseMetadata(md md.Metadata) (err error) {
+func (c *ssConnector) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		user           = "user"
 		key            = "key"
@@ -24,7 +24,7 @@ func (c *ssConnector) parseMetadata(md md.Metadata) (err error) {
 	)
 
 	var method, password string
-	if v := md.GetString(user); v != "" {
+	if v := mdata.GetString(md, user); v != "" {
 		ss := strings.SplitN(v, ":", 2)
 		if len(ss) == 1 {
 			method = ss[0]
@@ -32,13 +32,13 @@ func (c *ssConnector) parseMetadata(md md.Metadata) (err error) {
 			method, password = ss[0], ss[1]
 		}
 	}
-	c.md.cipher, err = ss.ShadowCipher(method, password, md.GetString(key))
+	c.md.cipher, err = ss.ShadowCipher(method, password, mdata.GetString(md, key))
 	if err != nil {
 		return
 	}
 
-	c.md.connectTimeout = md.GetDuration(connectTimeout)
+	c.md.connectTimeout = mdata.GetDuration(md, connectTimeout)
-	c.md.noDelay = md.GetBool(noDelay)
+	c.md.noDelay = mdata.GetBool(md, noDelay)
 
 	return
 }

pkg/connector/ss/udp/connector.go

@@ -72,7 +72,7 @@ func (c *ssuConnector) Connect(ctx context.Context, conn net.Conn, network, addr
 		}
 
 		// standard UDP relay
-		return ss.UDPClientConn(pc, conn.RemoteAddr(), taddr, c.md.udpBufferSize), nil
+		return ss.UDPClientConn(pc, conn.RemoteAddr(), taddr, c.md.bufferSize), nil
 	}
 
 	if c.md.cipher != nil {

pkg/connector/ss/udp/metadata.go

@@ -1,30 +1,31 @@
 package ss
 
 import (
+	"math"
 	"strings"
 	"time"
 
 	"github.com/go-gost/gost/pkg/common/util/ss"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 	"github.com/shadowsocks/go-shadowsocks2/core"
 )
 
 type metadata struct {
 	cipher         core.Cipher
 	connectTimeout time.Duration
-	udpBufferSize  int
+	bufferSize     int
 }
 
-func (c *ssuConnector) parseMetadata(md md.Metadata) (err error) {
+func (c *ssuConnector) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		user           = "user"
 		key            = "key"
 		connectTimeout = "timeout"
-		udpBufferSize  = "udpBufferSize" // udp buffer size
+		bufferSize     = "bufferSize" // udp buffer size
 	)
 
 	var method, password string
-	if v := md.GetString(user); v != "" {
+	if v := mdata.GetString(md, user); v != "" {
 		ss := strings.SplitN(v, ":", 2)
 		if len(ss) == 1 {
 			method = ss[0]
@@ -32,22 +33,17 @@ func (c *ssuConnector) parseMetadata(md md.Metadata) (err error) {
 			method, password = ss[0], ss[1]
 		}
 	}
-	c.md.cipher, err = ss.ShadowCipher(method, password, md.GetString(key))
+	c.md.cipher, err = ss.ShadowCipher(method, password, mdata.GetString(md, key))
 	if err != nil {
 		return
 	}
 
-	c.md.connectTimeout = md.GetDuration(connectTimeout)
+	c.md.connectTimeout = mdata.GetDuration(md, connectTimeout)
 
-	if c.md.udpBufferSize > 0 {
+	if bs := mdata.GetInt(md, bufferSize); bs > 0 {
-		if c.md.udpBufferSize < 512 {
+		c.md.bufferSize = int(math.Min(math.Max(float64(bs), 512), 64*1024))
-			c.md.udpBufferSize = 512
-		}
-		if c.md.udpBufferSize > 65*1024 {
-			c.md.udpBufferSize = 65 * 1024
-		}
 	} else {
-		c.md.udpBufferSize = 4096
+		c.md.bufferSize = 1024
 	}
 
 	return

pkg/dialer/forward/ssh/metadata.go

@@ -6,7 +6,7 @@ import (
 	"strings"
 	"time"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 	"golang.org/x/crypto/ssh"
 )
 
@@ -16,7 +16,7 @@ type metadata struct {
 	signer           ssh.Signer
 }
 
-func (d *forwardDialer) parseMetadata(md md.Metadata) (err error) {
+func (d *forwardDialer) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		handshakeTimeout = "handshakeTimeout"
 		user             = "user"
@@ -24,7 +24,7 @@ func (d *forwardDialer) parseMetadata(md md.Metadata) (err error) {
 		passphrase       = "passphrase"
 	)
 
-	if v := md.GetString(user); v != "" {
+	if v := mdata.GetString(md, user); v != "" {
 		ss := strings.SplitN(v, ":", 2)
 		if len(ss) == 1 {
 			d.md.user = url.User(ss[0])
@@ -33,13 +33,13 @@ func (d *forwardDialer) parseMetadata(md md.Metadata) (err error) {
 		}
 	}
 
-	if key := md.GetString(privateKeyFile); key != "" {
+	if key := mdata.GetString(md, privateKeyFile); key != "" {
 		data, err := ioutil.ReadFile(key)
 		if err != nil {
 			return err
 		}
 
-		pp := md.GetString(passphrase)
+		pp := mdata.GetString(md, passphrase)
 		if pp == "" {
 			d.md.signer, err = ssh.ParsePrivateKey(data)
 		} else {
@@ -50,7 +50,7 @@ func (d *forwardDialer) parseMetadata(md md.Metadata) (err error) {
 		}
 	}
 
-	d.md.handshakeTimeout = md.GetDuration(handshakeTimeout)
+	d.md.handshakeTimeout = mdata.GetDuration(md, handshakeTimeout)
 
 	return
 }

pkg/dialer/http2/h2/metadata.go

@@ -5,7 +5,7 @@ import (
 	"net"
 
 	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -14,7 +14,7 @@ type metadata struct {
 	tlsConfig *tls.Config
 }
 
-func (d *h2Dialer) parseMetadata(md md.Metadata) (err error) {
+func (d *h2Dialer) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		certFile   = "certFile"
 		keyFile    = "keyFile"
@@ -24,20 +24,20 @@ func (d *h2Dialer) parseMetadata(md md.Metadata) (err error) {
 		path       = "path"
 	)
 
-	d.md.host = md.GetString(serverName)
+	d.md.host = mdata.GetString(md, serverName)
 	sn, _, _ := net.SplitHostPort(d.md.host)
 	if sn == "" {
 		sn = "localhost"
 	}
 	d.md.tlsConfig, err = tls_util.LoadClientConfig(
-		md.GetString(certFile),
+		mdata.GetString(md, certFile),
-		md.GetString(keyFile),
+		mdata.GetString(md, keyFile),
-		md.GetString(caFile),
+		mdata.GetString(md, caFile),
-		md.GetBool(secure),
+		mdata.GetBool(md, secure),
 		sn,
 	)
 
-	d.md.path = md.GetString(path)
+	d.md.path = mdata.GetString(md, path)
 
 	return
 }

pkg/dialer/http2/metadata.go

@@ -5,14 +5,14 @@ import (
 	"net"
 
 	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
 	tlsConfig *tls.Config
 }
 
-func (d *http2Dialer) parseMetadata(md md.Metadata) (err error) {
+func (d *http2Dialer) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		certFile   = "certFile"
 		keyFile    = "keyFile"
@@ -21,15 +21,15 @@ func (d *http2Dialer) parseMetadata(md md.Metadata) (err error) {
 		serverName = "serverName"
 	)
 
-	sn, _, _ := net.SplitHostPort(md.GetString(serverName))
+	sn, _, _ := net.SplitHostPort(mdata.GetString(md, serverName))
 	if sn == "" {
 		sn = "localhost"
 	}
 	d.md.tlsConfig, err = tls_util.LoadClientConfig(
-		md.GetString(certFile),
+		mdata.GetString(md, certFile),
-		md.GetString(keyFile),
+		mdata.GetString(md, keyFile),
-		md.GetString(caFile),
+		mdata.GetString(md, caFile),
-		md.GetBool(secure),
+		mdata.GetBool(md, secure),
 		sn,
 	)
 

pkg/dialer/kcp/metadata.go

@@ -5,7 +5,7 @@ import (
 	"time"
 
 	kcp_util "github.com/go-gost/gost/pkg/common/util/kcp"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -13,19 +13,13 @@ type metadata struct {
 	config           *kcp_util.Config
 }
 
-func (d *kcpDialer) parseMetadata(md md.Metadata) (err error) {
+func (d *kcpDialer) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		config           = "config"
 		handshakeTimeout = "handshakeTimeout"
 	)
 
-	if mm, _ := md.Get(config).(map[interface{}]interface{}); len(mm) > 0 {
+	if m := mdata.GetStringMap(md, config); len(m) > 0 {
-		m := make(map[string]interface{})
-		for k, v := range mm {
-			if sk, ok := k.(string); ok {
-				m[sk] = v
-			}
-		}
 		b, err := json.Marshal(m)
 		if err != nil {
 			return err
@@ -36,11 +30,10 @@ func (d *kcpDialer) parseMetadata(md md.Metadata) (err error) {
 		}
 		d.md.config = cfg
 	}
-
 	if d.md.config == nil {
 		d.md.config = kcp_util.DefaultConfig
 	}
 
-	d.md.handshakeTimeout = md.GetDuration(handshakeTimeout)
+	d.md.handshakeTimeout = mdata.GetDuration(md, handshakeTimeout)
 	return
 }

pkg/dialer/obfs/http/metadata.go

@@ -1,10 +1,9 @@
 package http
 
 import (
-	"fmt"
 	"net/http"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -12,19 +11,19 @@ type metadata struct {
 	header http.Header
 }
 
-func (d *obfsHTTPDialer) parseMetadata(md md.Metadata) (err error) {
+func (d *obfsHTTPDialer) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		header = "header"
 		host   = "host"
 	)
 
-	if mm, _ := md.Get(header).(map[interface{}]interface{}); len(mm) > 0 {
+	if m := mdata.GetStringMapString(md, header); len(m) > 0 {
 		h := http.Header{}
-		for k, v := range mm {
+		for k, v := range m {
-			h.Add(fmt.Sprintf("%v", k), fmt.Sprintf("%v", v))
+			h.Add(k, v)
 		}
 		d.md.header = h
 	}
-	d.md.host = md.GetString(host)
+	d.md.host = mdata.GetString(md, host)
 	return
 }

pkg/dialer/obfs/tls/metadata.go

@@ -1,18 +1,18 @@
 package tls
 
 import (
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
 	host string
 }
 
-func (d *obfsTLSDialer) parseMetadata(md md.Metadata) (err error) {
+func (d *obfsTLSDialer) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		host = "host"
 	)
 
-	d.md.host = md.GetString(host)
+	d.md.host = mdata.GetString(md, host)
 	return
 }

pkg/dialer/quic/metadata.go

@@ -6,7 +6,7 @@ import (
 	"time"
 
 	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -18,7 +18,7 @@ type metadata struct {
 	tlsConfig *tls.Config
 }
 
-func (d *quicDialer) parseMetadata(md md.Metadata) (err error) {
+func (d *quicDialer) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		keepAlive        = "keepAlive"
 		handshakeTimeout = "handshakeTimeout"
@@ -33,26 +33,26 @@ func (d *quicDialer) parseMetadata(md md.Metadata) (err error) {
 		cipherKey = "cipherKey"
 	)
 
-	d.md.handshakeTimeout = md.GetDuration(handshakeTimeout)
+	d.md.handshakeTimeout = mdata.GetDuration(md, handshakeTimeout)
 
-	if key := md.GetString(cipherKey); key != "" {
+	if key := mdata.GetString(md, cipherKey); key != "" {
 		d.md.cipherKey = []byte(key)
 	}
 
-	sn, _, _ := net.SplitHostPort(md.GetString(serverName))
+	sn, _, _ := net.SplitHostPort(mdata.GetString(md, serverName))
 	if sn == "" {
 		sn = "localhost"
 	}
 	d.md.tlsConfig, err = tls_util.LoadClientConfig(
-		md.GetString(certFile),
+		mdata.GetString(md, certFile),
-		md.GetString(keyFile),
+		mdata.GetString(md, keyFile),
-		md.GetString(caFile),
+		mdata.GetString(md, caFile),
-		md.GetBool(secure),
+		mdata.GetBool(md, secure),
 		sn,
 	)
 
-	d.md.keepAlive = md.GetBool(keepAlive)
+	d.md.keepAlive = mdata.GetBool(md, keepAlive)
-	d.md.handshakeTimeout = md.GetDuration(handshakeTimeout)
+	d.md.handshakeTimeout = mdata.GetDuration(md, handshakeTimeout)
-	d.md.maxIdleTimeout = md.GetDuration(maxIdleTimeout)
+	d.md.maxIdleTimeout = mdata.GetDuration(md, maxIdleTimeout)
 	return
 }

pkg/dialer/ssh/metadata.go

@@ -6,7 +6,7 @@ import (
 	"strings"
 	"time"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 	"golang.org/x/crypto/ssh"
 )
 
@@ -16,7 +16,7 @@ type metadata struct {
 	signer           ssh.Signer
 }
 
-func (d *sshDialer) parseMetadata(md md.Metadata) (err error) {
+func (d *sshDialer) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		handshakeTimeout = "handshakeTimeout"
 		user             = "user"
@@ -24,7 +24,7 @@ func (d *sshDialer) parseMetadata(md md.Metadata) (err error) {
 		passphrase       = "passphrase"
 	)
 
-	if v := md.GetString(user); v != "" {
+	if v := mdata.GetString(md, user); v != "" {
 		ss := strings.SplitN(v, ":", 2)
 		if len(ss) == 1 {
 			d.md.user = url.User(ss[0])
@@ -33,13 +33,13 @@ func (d *sshDialer) parseMetadata(md md.Metadata) (err error) {
 		}
 	}
 
-	if key := md.GetString(privateKeyFile); key != "" {
+	if key := mdata.GetString(md, privateKeyFile); key != "" {
 		data, err := ioutil.ReadFile(key)
 		if err != nil {
 			return err
 		}
 
-		pp := md.GetString(passphrase)
+		pp := mdata.GetString(md, passphrase)
 		if pp == "" {
 			d.md.signer, err = ssh.ParsePrivateKey(data)
 		} else {
@@ -50,7 +50,7 @@ func (d *sshDialer) parseMetadata(md md.Metadata) (err error) {
 		}
 	}
 
-	d.md.handshakeTimeout = md.GetDuration(handshakeTimeout)
+	d.md.handshakeTimeout = mdata.GetDuration(md, handshakeTimeout)
 
 	return
 }

pkg/dialer/tls/metadata.go

@@ -6,7 +6,7 @@ import (
 	"time"
 
 	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -14,7 +14,7 @@ type metadata struct {
 	handshakeTimeout time.Duration
 }
 
-func (d *tlsDialer) parseMetadata(md md.Metadata) (err error) {
+func (d *tlsDialer) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		certFile   = "certFile"
 		keyFile    = "keyFile"
@@ -25,19 +25,19 @@ func (d *tlsDialer) parseMetadata(md md.Metadata) (err error) {
 		handshakeTimeout = "handshakeTimeout"
 	)
 
-	sn, _, _ := net.SplitHostPort(md.GetString(serverName))
+	sn, _, _ := net.SplitHostPort(mdata.GetString(md, serverName))
 	if sn == "" {
 		sn = "localhost"
 	}
 	d.md.tlsConfig, err = tls_util.LoadClientConfig(
-		md.GetString(certFile),
+		mdata.GetString(md, certFile),
-		md.GetString(keyFile),
+		mdata.GetString(md, keyFile),
-		md.GetString(caFile),
+		mdata.GetString(md, caFile),
-		md.GetBool(secure),
+		mdata.GetBool(md, secure),
 		sn,
 	)
 
-	d.md.handshakeTimeout = md.GetDuration(handshakeTimeout)
+	d.md.handshakeTimeout = mdata.GetDuration(md, handshakeTimeout)
 
 	return
 }

pkg/dialer/tls/mux/metadata.go

@@ -6,7 +6,7 @@ import (
 	"time"
 
 	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -21,7 +21,7 @@ type metadata struct {
 	muxMaxStreamBuffer   int
 }
 
-func (d *mtlsDialer) parseMetadata(md md.Metadata) (err error) {
+func (d *mtlsDialer) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		certFile   = "certFile"
 		keyFile    = "keyFile"
@@ -39,25 +39,25 @@ func (d *mtlsDialer) parseMetadata(md md.Metadata) (err error) {
 		muxMaxStreamBuffer   = "muxMaxStreamBuffer"
 	)
 
-	sn, _, _ := net.SplitHostPort(md.GetString(serverName))
+	sn, _, _ := net.SplitHostPort(mdata.GetString(md, serverName))
 	if sn == "" {
 		sn = "localhost"
 	}
 	d.md.tlsConfig, err = tls_util.LoadClientConfig(
-		md.GetString(certFile),
+		mdata.GetString(md, certFile),
-		md.GetString(keyFile),
+		mdata.GetString(md, keyFile),
-		md.GetString(caFile),
+		mdata.GetString(md, caFile),
-		md.GetBool(secure),
+		mdata.GetBool(md, secure),
 		sn,
 	)
-	d.md.handshakeTimeout = md.GetDuration(handshakeTimeout)
+	d.md.handshakeTimeout = mdata.GetDuration(md, handshakeTimeout)
 
-	d.md.muxKeepAliveDisabled = md.GetBool(muxKeepAliveDisabled)
+	d.md.muxKeepAliveDisabled = mdata.GetBool(md, muxKeepAliveDisabled)
-	d.md.muxKeepAliveInterval = md.GetDuration(muxKeepAliveInterval)
+	d.md.muxKeepAliveInterval = mdata.GetDuration(md, muxKeepAliveInterval)
-	d.md.muxKeepAliveTimeout = md.GetDuration(muxKeepAliveTimeout)
+	d.md.muxKeepAliveTimeout = mdata.GetDuration(md, muxKeepAliveTimeout)
-	d.md.muxMaxFrameSize = md.GetInt(muxMaxFrameSize)
+	d.md.muxMaxFrameSize = mdata.GetInt(md, muxMaxFrameSize)
-	d.md.muxMaxReceiveBuffer = md.GetInt(muxMaxReceiveBuffer)
+	d.md.muxMaxReceiveBuffer = mdata.GetInt(md, muxMaxReceiveBuffer)
-	d.md.muxMaxStreamBuffer = md.GetInt(muxMaxStreamBuffer)
+	d.md.muxMaxStreamBuffer = mdata.GetInt(md, muxMaxStreamBuffer)
 
 	return
 }

pkg/dialer/ws/metadata.go

@@ -2,13 +2,12 @@ package ws
 
 import (
 	"crypto/tls"
-	"fmt"
 	"net"
 	"net/http"
 	"time"
 
 	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 const (
@@ -29,7 +28,7 @@ type metadata struct {
 	header http.Header
 }
 
-func (d *wsDialer) parseMetadata(md md.Metadata) (err error) {
+func (d *wsDialer) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		path = "path"
 		host = "host"
@@ -49,35 +48,35 @@ func (d *wsDialer) parseMetadata(md md.Metadata) (err error) {
 		header = "header"
 	)
 
-	d.md.path = md.GetString(path)
+	d.md.path = mdata.GetString(md, path)
 	if d.md.path == "" {
 		d.md.path = defaultPath
 	}
 
-	d.md.host = md.GetString(host)
+	d.md.host = mdata.GetString(md, host)
 
-	sn, _, _ := net.SplitHostPort(md.GetString(serverName))
+	sn, _, _ := net.SplitHostPort(mdata.GetString(md, serverName))
 	if sn == "" {
 		sn = "localhost"
 	}
 	d.md.tlsConfig, err = tls_util.LoadClientConfig(
-		md.GetString(certFile),
+		mdata.GetString(md, certFile),
-		md.GetString(keyFile),
+		mdata.GetString(md, keyFile),
-		md.GetString(caFile),
+		mdata.GetString(md, caFile),
-		md.GetBool(secure),
+		mdata.GetBool(md, secure),
 		sn,
 	)
 
-	d.md.handshakeTimeout = md.GetDuration(handshakeTimeout)
+	d.md.handshakeTimeout = mdata.GetDuration(md, handshakeTimeout)
-	d.md.readHeaderTimeout = md.GetDuration(readHeaderTimeout)
+	d.md.readHeaderTimeout = mdata.GetDuration(md, readHeaderTimeout)
-	d.md.readBufferSize = md.GetInt(readBufferSize)
+	d.md.readBufferSize = mdata.GetInt(md, readBufferSize)
-	d.md.writeBufferSize = md.GetInt(writeBufferSize)
+	d.md.writeBufferSize = mdata.GetInt(md, writeBufferSize)
-	d.md.enableCompression = md.GetBool(enableCompression)
+	d.md.enableCompression = mdata.GetBool(md, enableCompression)
 
-	if mm, _ := md.Get(header).(map[interface{}]interface{}); len(mm) > 0 {
+	if m := mdata.GetStringMapString(md, header); len(m) > 0 {
 		h := http.Header{}
-		for k, v := range mm {
+		for k, v := range m {
-			h.Add(fmt.Sprintf("%v", k), fmt.Sprintf("%v", v))
+			h.Add(k, v)
 		}
 		d.md.header = h
 	}

pkg/dialer/ws/mux/metadata.go

@@ -2,13 +2,12 @@ package mux
 
 import (
 	"crypto/tls"
-	"fmt"
 	"net"
 	"net/http"
 	"time"
 
 	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 const (
@@ -36,7 +35,7 @@ type metadata struct {
 	header http.Header
 }
 
-func (d *mwsDialer) parseMetadata(md md.Metadata) (err error) {
+func (d *mwsDialer) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		path = "path"
 		host = "host"
@@ -63,42 +62,42 @@ func (d *mwsDialer) parseMetadata(md md.Metadata) (err error) {
 		muxMaxStreamBuffer   = "muxMaxStreamBuffer"
 	)
 
-	d.md.path = md.GetString(path)
+	d.md.path = mdata.GetString(md, path)
 	if d.md.path == "" {
 		d.md.path = defaultPath
 	}
 
-	d.md.host = md.GetString(host)
+	d.md.host = mdata.GetString(md, host)
 
-	sn, _, _ := net.SplitHostPort(md.GetString(serverName))
+	sn, _, _ := net.SplitHostPort(mdata.GetString(md, serverName))
 	if sn == "" {
 		sn = "localhost"
 	}
 	d.md.tlsConfig, err = tls_util.LoadClientConfig(
-		md.GetString(certFile),
+		mdata.GetString(md, certFile),
-		md.GetString(keyFile),
+		mdata.GetString(md, keyFile),
-		md.GetString(caFile),
+		mdata.GetString(md, caFile),
-		md.GetBool(secure),
+		mdata.GetBool(md, secure),
 		sn,
 	)
 
-	d.md.muxKeepAliveDisabled = md.GetBool(muxKeepAliveDisabled)
+	d.md.muxKeepAliveDisabled = mdata.GetBool(md, muxKeepAliveDisabled)
-	d.md.muxKeepAliveInterval = md.GetDuration(muxKeepAliveInterval)
+	d.md.muxKeepAliveInterval = mdata.GetDuration(md, muxKeepAliveInterval)
-	d.md.muxKeepAliveTimeout = md.GetDuration(muxKeepAliveTimeout)
+	d.md.muxKeepAliveTimeout = mdata.GetDuration(md, muxKeepAliveTimeout)
-	d.md.muxMaxFrameSize = md.GetInt(muxMaxFrameSize)
+	d.md.muxMaxFrameSize = mdata.GetInt(md, muxMaxFrameSize)
-	d.md.muxMaxReceiveBuffer = md.GetInt(muxMaxReceiveBuffer)
+	d.md.muxMaxReceiveBuffer = mdata.GetInt(md, muxMaxReceiveBuffer)
-	d.md.muxMaxStreamBuffer = md.GetInt(muxMaxStreamBuffer)
+	d.md.muxMaxStreamBuffer = mdata.GetInt(md, muxMaxStreamBuffer)
 
-	d.md.handshakeTimeout = md.GetDuration(handshakeTimeout)
+	d.md.handshakeTimeout = mdata.GetDuration(md, handshakeTimeout)
-	d.md.readHeaderTimeout = md.GetDuration(readHeaderTimeout)
+	d.md.readHeaderTimeout = mdata.GetDuration(md, readHeaderTimeout)
-	d.md.readBufferSize = md.GetInt(readBufferSize)
+	d.md.readBufferSize = mdata.GetInt(md, readBufferSize)
-	d.md.writeBufferSize = md.GetInt(writeBufferSize)
+	d.md.writeBufferSize = mdata.GetInt(md, writeBufferSize)
-	d.md.enableCompression = md.GetBool(enableCompression)
+	d.md.enableCompression = mdata.GetBool(md, enableCompression)
 
-	if mm, _ := md.Get(header).(map[interface{}]interface{}); len(mm) > 0 {
+	if m := mdata.GetStringMapString(md, header); len(m) > 0 {
 		h := http.Header{}
-		for k, v := range mm {
+		for k, v := range m {
-			h.Add(fmt.Sprintf("%v", k), fmt.Sprintf("%v", v))
+			h.Add(k, v)
 		}
 		d.md.header = h
 	}

pkg/handler/forward/local/metadata.go

@@ -3,7 +3,7 @@ package local
 import (
 	"time"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -11,13 +11,13 @@ type metadata struct {
 	retryCount  int
 }
 
-func (h *forwardHandler) parseMetadata(md md.Metadata) (err error) {
+func (h *forwardHandler) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		readTimeout = "readTimeout"
 		retryCount  = "retry"
 	)
 
-	h.md.readTimeout = md.GetDuration(readTimeout)
+	h.md.readTimeout = mdata.GetDuration(md, readTimeout)
-	h.md.retryCount = md.GetInt(retryCount)
+	h.md.retryCount = mdata.GetInt(md, retryCount)
 	return
 }

pkg/handler/forward/remote/metadata.go

@@ -3,7 +3,7 @@ package remote
 import (
 	"time"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -11,13 +11,13 @@ type metadata struct {
 	retryCount  int
 }
 
-func (h *forwardHandler) parseMetadata(md md.Metadata) (err error) {
+func (h *forwardHandler) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		readTimeout = "readTimeout"
 		retryCount  = "retry"
 	)
 
-	h.md.readTimeout = md.GetDuration(readTimeout)
+	h.md.readTimeout = mdata.GetDuration(md, readTimeout)
-	h.md.retryCount = md.GetInt(retryCount)
+	h.md.retryCount = mdata.GetInt(md, retryCount)
 	return
 }

pkg/handler/forward/ssh/metadata.go

@@ -7,7 +7,7 @@ import (
 	"github.com/go-gost/gost/pkg/auth"
 	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
 	ssh_util "github.com/go-gost/gost/pkg/internal/util/ssh"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 	"golang.org/x/crypto/ssh"
 )
 
@@ -17,7 +17,7 @@ type metadata struct {
 	authorizedKeys map[string]bool
 }
 
-func (h *forwardHandler) parseMetadata(md md.Metadata) (err error) {
+func (h *forwardHandler) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		users          = "users"
 		authorizedKeys = "authorizedKeys"
@@ -25,28 +25,26 @@ func (h *forwardHandler) parseMetadata(md md.Metadata) (err error) {
 		passphrase     = "passphrase"
 	)
 
-	if v, _ := md.Get(users).([]interface{}); len(v) > 0 {
+	if auths := mdata.GetStrings(md, users); len(auths) > 0 {
 		authenticator := auth.NewLocalAuthenticator(nil)
-		for _, auth := range v {
+		for _, auth := range auths {
-			if s, _ := auth.(string); s != "" {
+			ss := strings.SplitN(auth, ":", 2)
-				ss := strings.SplitN(s, ":", 2)
+			if len(ss) == 1 {
-				if len(ss) == 1 {
+				authenticator.Add(ss[0], "")
-					authenticator.Add(ss[0], "")
+			} else {
-				} else {
+				authenticator.Add(ss[0], ss[1])
-					authenticator.Add(ss[0], ss[1])
-				}
 			}
 		}
 		h.md.authenticator = authenticator
 	}
 
-	if key := md.GetString(privateKeyFile); key != "" {
+	if key := mdata.GetString(md, privateKeyFile); key != "" {
 		data, err := ioutil.ReadFile(key)
 		if err != nil {
 			return err
 		}
 
-		pp := md.GetString(passphrase)
+		pp := mdata.GetString(md, passphrase)
 		if pp == "" {
 			h.md.signer, err = ssh.ParsePrivateKey(data)
 		} else {
@@ -64,7 +62,7 @@ func (h *forwardHandler) parseMetadata(md md.Metadata) (err error) {
 		h.md.signer = signer
 	}
 
-	if name := md.GetString(authorizedKeys); name != "" {
+	if name := mdata.GetString(md, authorizedKeys); name != "" {
 		m, err := ssh_util.ParseAuthorizedKeysFile(name)
 		if err != nil {
 			return err

pkg/handler/http/metadata.go

@@ -28,7 +28,7 @@ func (h *httpHandler) parseMetadata(md mdata.Metadata) error {
 		enableUDP      = "udp"
 	)
 
-	if auths := md.GetStrings(users); len(auths) > 0 {
+	if auths := mdata.GetStrings(md, users); len(auths) > 0 {
 		authenticator := auth.NewLocalAuthenticator(nil)
 		for _, auth := range auths {
 			ss := strings.SplitN(auth, ":", 2)
@@ -41,26 +41,26 @@ func (h *httpHandler) parseMetadata(md mdata.Metadata) error {
 		h.md.authenticator = authenticator
 	}
 
-	if mm := mdata.GetStringMapString(md, header); len(mm) > 0 {
+	if m := mdata.GetStringMapString(md, header); len(m) > 0 {
 		hd := http.Header{}
-		for k, v := range mm {
+		for k, v := range m {
 			hd.Add(k, v)
 		}
 		h.md.header = hd
 	}
 
-	if v := md.GetString(probeResistKey); v != "" {
+	if v := mdata.GetString(md, probeResistKey); v != "" {
 		if ss := strings.SplitN(v, ":", 2); len(ss) == 2 {
 			h.md.probeResist = &probeResist{
 				Type:  ss[0],
 				Value: ss[1],
-				Knock: md.GetString(knock),
+				Knock: mdata.GetString(md, knock),
 			}
 		}
 	}
-	h.md.retryCount = md.GetInt(retryCount)
+	h.md.retryCount = mdata.GetInt(md, retryCount)
-	h.md.sni = md.GetBool(sni)
+	h.md.sni = mdata.GetBool(md, sni)
-	h.md.enableUDP = md.GetBool(enableUDP)
+	h.md.enableUDP = mdata.GetBool(md, enableUDP)
 
 	return nil
 }

pkg/handler/http2/metadata.go

@@ -4,7 +4,7 @@ import (
 	"strings"
 
 	"github.com/go-gost/gost/pkg/auth"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -16,7 +16,7 @@ type metadata struct {
 	enableUDP     bool
 }
 
-func (h *http2Handler) parseMetadata(md md.Metadata) error {
+func (h *http2Handler) parseMetadata(md mdata.Metadata) error {
 	const (
 		proxyAgent     = "proxyAgent"
 		users          = "users"
@@ -27,9 +27,9 @@ func (h *http2Handler) parseMetadata(md md.Metadata) error {
 		enableUDP      = "udp"
 	)
 
-	h.md.proxyAgent = md.GetString(proxyAgent)
+	h.md.proxyAgent = mdata.GetString(md, proxyAgent)
 
-	if auths := md.GetStrings(users); len(auths) > 0 {
+	if auths := mdata.GetStrings(md, users); len(auths) > 0 {
 		authenticator := auth.NewLocalAuthenticator(nil)
 		for _, auth := range auths {
 			ss := strings.SplitN(auth, ":", 2)
@@ -42,18 +42,18 @@ func (h *http2Handler) parseMetadata(md md.Metadata) error {
 		h.md.authenticator = authenticator
 	}
 
-	if v := md.GetString(probeResistKey); v != "" {
+	if v := mdata.GetString(md, probeResistKey); v != "" {
 		if ss := strings.SplitN(v, ":", 2); len(ss) == 2 {
 			h.md.probeResist = &probeResist{
 				Type:  ss[0],
 				Value: ss[1],
-				Knock: md.GetString(knock),
+				Knock: mdata.GetString(md, knock),
 			}
 		}
 	}
-	h.md.retryCount = md.GetInt(retryCount)
+	h.md.retryCount = mdata.GetInt(md, retryCount)
-	h.md.sni = md.GetBool(sni)
+	h.md.sni = mdata.GetBool(md, sni)
-	h.md.enableUDP = md.GetBool(enableUDP)
+	h.md.enableUDP = mdata.GetBool(md, enableUDP)
 
 	return nil
 }

pkg/handler/redirect/metadata.go

@@ -1,18 +1,18 @@
 package redirect
 
 import (
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
 	retryCount int
 }
 
-func (h *redirectHandler) parseMetadata(md md.Metadata) (err error) {
+func (h *redirectHandler) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		retryCount = "retry"
 	)
 
-	h.md.retryCount = md.GetInt(retryCount)
+	h.md.retryCount = mdata.GetInt(md, retryCount)
 	return
 }

pkg/handler/relay/metadata.go

@@ -1,11 +1,12 @@
 package relay
 
 import (
+	"math"
 	"strings"
 	"time"
 
 	"github.com/go-gost/gost/pkg/auth"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -17,7 +18,7 @@ type metadata struct {
 	noDelay       bool
 }
 
-func (h *relayHandler) parseMetadata(md md.Metadata) (err error) {
+func (h *relayHandler) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		users         = "users"
 		readTimeout   = "readTimeout"
@@ -27,7 +28,7 @@ func (h *relayHandler) parseMetadata(md md.Metadata) (err error) {
 		noDelay       = "nodelay"
 	)
 
-	if auths := md.GetStrings(users); len(auths) > 0 {
+	if auths := mdata.GetStrings(md, users); len(auths) > 0 {
 		authenticator := auth.NewLocalAuthenticator(nil)
 		for _, auth := range auths {
 			ss := strings.SplitN(auth, ":", 2)
@@ -40,20 +41,15 @@ func (h *relayHandler) parseMetadata(md md.Metadata) (err error) {
 		h.md.authenticator = authenticator
 	}
 
-	h.md.readTimeout = md.GetDuration(readTimeout)
+	h.md.readTimeout = mdata.GetDuration(md, readTimeout)
-	h.md.retryCount = md.GetInt(retryCount)
+	h.md.retryCount = mdata.GetInt(md, retryCount)
-	h.md.enableBind = md.GetBool(enableBind)
+	h.md.enableBind = mdata.GetBool(md, enableBind)
-	h.md.noDelay = md.GetBool(noDelay)
+	h.md.noDelay = mdata.GetBool(md, noDelay)
-	h.md.udpBufferSize = md.GetInt(udpBufferSize)
+
-	if h.md.udpBufferSize > 0 {
+	if bs := mdata.GetInt(md, udpBufferSize); bs > 0 {
-		if h.md.udpBufferSize < 512 {
+		h.md.udpBufferSize = int(math.Min(math.Max(float64(bs), 512), 64*1024))
-			h.md.udpBufferSize = 512 // min buffer size
-		}
-		if h.md.udpBufferSize > 65*1024 {
-			h.md.udpBufferSize = 65 * 1024 // max buffer size
-		}
 	} else {
-		h.md.udpBufferSize = 1024 // default buffer size
+		h.md.udpBufferSize = 1024
 	}
 	return
 }

pkg/handler/sni/metadata.go

@@ -3,7 +3,7 @@ package sni
 import (
 	"time"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -11,13 +11,13 @@ type metadata struct {
 	retryCount  int
 }
 
-func (h *sniHandler) parseMetadata(md md.Metadata) (err error) {
+func (h *sniHandler) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		readTimeout = "readTimeout"
 		retryCount  = "retry"
 	)
 
-	h.md.readTimeout = md.GetDuration(readTimeout)
+	h.md.readTimeout = mdata.GetDuration(md, readTimeout)
-	h.md.retryCount = md.GetInt(retryCount)
+	h.md.retryCount = mdata.GetInt(md, retryCount)
 	return
 }

pkg/handler/socks/v4/metadata.go

@@ -4,7 +4,7 @@ import (
 	"time"
 
 	"github.com/go-gost/gost/pkg/auth"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -13,24 +13,24 @@ type metadata struct {
 	retryCount    int
 }
 
-func (h *socks4Handler) parseMetadata(md md.Metadata) (err error) {
+func (h *socks4Handler) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		users       = "users"
 		readTimeout = "readTimeout"
 		retryCount  = "retry"
 	)
 
-	if v, _ := md.Get(users).([]interface{}); len(v) > 0 {
+	if auths := mdata.GetStrings(md, users); len(auths) > 0 {
 		authenticator := auth.NewLocalAuthenticator(nil)
-		for _, auth := range v {
+		for _, auth := range auths {
-			if v, _ := auth.(string); v != "" {
+			if auth != "" {
-				authenticator.Add(v, "")
+				authenticator.Add(auth, "")
 			}
 		}
 		h.md.authenticator = authenticator
 	}
 
-	h.md.readTimeout = md.GetDuration(readTimeout)
+	h.md.readTimeout = mdata.GetDuration(md, readTimeout)
-	h.md.retryCount = md.GetInt(retryCount)
+	h.md.retryCount = mdata.GetInt(md, retryCount)
 	return
 }

pkg/handler/socks/v5/metadata.go

@@ -2,12 +2,13 @@ package v5
 
 import (
 	"crypto/tls"
+	"math"
 	"strings"
 	"time"
 
 	"github.com/go-gost/gost/pkg/auth"
 	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
@@ -23,7 +24,7 @@ type metadata struct {
 	compatibilityMode bool
 }
 
-func (h *socks5Handler) parseMetadata(md md.Metadata) (err error) {
+func (h *socks5Handler) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		certFile          = "certFile"
 		keyFile           = "keyFile"
@@ -40,49 +41,41 @@ func (h *socks5Handler) parseMetadata(md md.Metadata) (err error) {
 	)
 
 	h.md.tlsConfig, err = tls_util.LoadServerConfig(
-		md.GetString(certFile),
+		mdata.GetString(md, certFile),
-		md.GetString(keyFile),
+		mdata.GetString(md, keyFile),
-		md.GetString(caFile),
+		mdata.GetString(md, caFile),
 	)
 	if err != nil {
 		return
 	}
 
-	if v, _ := md.Get(users).([]interface{}); len(v) > 0 {
+	if auths := mdata.GetStrings(md, users); len(auths) > 0 {
 		authenticator := auth.NewLocalAuthenticator(nil)
-		for _, auth := range v {
+		for _, auth := range auths {
-			if s, _ := auth.(string); s != "" {
+			ss := strings.SplitN(auth, ":", 2)
-				ss := strings.SplitN(s, ":", 2)
+			if len(ss) == 1 {
-				if len(ss) == 1 {
+				authenticator.Add(ss[0], "")
-					authenticator.Add(ss[0], "")
+			} else {
-				} else {
+				authenticator.Add(ss[0], ss[1])
-					authenticator.Add(ss[0], ss[1])
-				}
 			}
 		}
 		h.md.authenticator = authenticator
 	}
 
-	h.md.readTimeout = md.GetDuration(readTimeout)
+	h.md.readTimeout = mdata.GetDuration(md, readTimeout)
-	h.md.timeout = md.GetDuration(timeout)
+	h.md.timeout = mdata.GetDuration(md, timeout)
-	h.md.retryCount = md.GetInt(retryCount)
+	h.md.retryCount = mdata.GetInt(md, retryCount)
-	h.md.noTLS = md.GetBool(noTLS)
+	h.md.noTLS = mdata.GetBool(md, noTLS)
-	h.md.enableBind = md.GetBool(enableBind)
+	h.md.enableBind = mdata.GetBool(md, enableBind)
-	h.md.enableUDP = md.GetBool(enableUDP)
+	h.md.enableUDP = mdata.GetBool(md, enableUDP)
 
-	h.md.udpBufferSize = md.GetInt(udpBufferSize)
+	if bs := mdata.GetInt(md, udpBufferSize); bs > 0 {
-	if h.md.udpBufferSize > 0 {
+		h.md.udpBufferSize = int(math.Min(math.Max(float64(bs), 512), 64*1024))
-		if h.md.udpBufferSize < 512 {
-			h.md.udpBufferSize = 512 // min buffer size
-		}
-		if h.md.udpBufferSize > 65*1024 {
-			h.md.udpBufferSize = 65 * 1024 // max buffer size
-		}
 	} else {
-		h.md.udpBufferSize = 1024 // default buffer size
+		h.md.udpBufferSize = 1024
 	}
 
-	h.md.compatibilityMode = md.GetBool(compatibilityMode)
+	h.md.compatibilityMode = mdata.GetBool(md, compatibilityMode)
 
 	return nil
 }

pkg/handler/ss/handler.go

@@ -76,7 +76,7 @@ func (h *ssHandler) Handle(ctx context.Context, conn net.Conn) {
 	addr := &gosocks5.Addr{}
 	if _, err := addr.ReadFrom(conn); err != nil {
 		h.logger.Error(err)
-		h.discard(conn)
+		io.Copy(ioutil.Discard, conn)
 		return
 	}
 
@@ -110,7 +110,3 @@ func (h *ssHandler) Handle(ctx context.Context, conn net.Conn) {
 		}).
 		Infof("%s >-< %s", conn.RemoteAddr(), addr)
 }
-
-func (h *ssHandler) discard(conn net.Conn) {
-	io.Copy(ioutil.Discard, conn)
-}

pkg/handler/ss/metadata.go

@@ -5,7 +5,7 @@ import (
 	"time"
 
 	"github.com/go-gost/gost/pkg/common/util/ss"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 	"github.com/shadowsocks/go-shadowsocks2/core"
 )
 
@@ -15,7 +15,7 @@ type metadata struct {
 	retryCount  int
 }
 
-func (h *ssHandler) parseMetadata(md md.Metadata) (err error) {
+func (h *ssHandler) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		users       = "users"
 		key         = "key"
@@ -24,26 +24,22 @@ func (h *ssHandler) parseMetadata(md md.Metadata) (err error) {
 	)
 
 	var method, password string
-	if v, _ := md.Get(users).([]interface{}); len(v) > 0 {
+	if auths := mdata.GetStrings(md, users); len(auths) > 0 {
-		h.logger.Info(v)
+		auth := auths[0]
-		for _, auth := range v {
+		ss := strings.SplitN(auth, ":", 2)
-			if s, _ := auth.(string); s != "" {
+		if len(ss) == 1 {
-				ss := strings.SplitN(s, ":", 2)
+			method = ss[0]
-				if len(ss) == 1 {
+		} else {
-					method = ss[0]
+			method, password = ss[0], ss[1]
-				} else {
-					method, password = ss[0], ss[1]
-				}
-			}
 		}
 	}
-	h.md.cipher, err = ss.ShadowCipher(method, password, md.GetString(key))
+	h.md.cipher, err = ss.ShadowCipher(method, password, mdata.GetString(md, key))
 	if err != nil {
 		return
 	}
 
-	h.md.readTimeout = md.GetDuration(readTimeout)
+	h.md.readTimeout = mdata.GetDuration(md, readTimeout)
-	h.md.retryCount = md.GetInt(retryCount)
+	h.md.retryCount = mdata.GetInt(md, retryCount)
 
 	return
 }

pkg/handler/ss/udp/metadata.go

@@ -1,11 +1,12 @@
 package ss
 
 import (
+	"math"
 	"strings"
 	"time"
 
 	"github.com/go-gost/gost/pkg/common/util/ss"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 	"github.com/shadowsocks/go-shadowsocks2/core"
 )
 
@@ -16,7 +17,7 @@ type metadata struct {
 	bufferSize  int
 }
 
-func (h *ssuHandler) parseMetadata(md md.Metadata) (err error) {
+func (h *ssuHandler) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		users       = "users"
 		key         = "key"
@@ -26,36 +27,27 @@ func (h *ssuHandler) parseMetadata(md md.Metadata) (err error) {
 	)
 
 	var method, password string
-	if v, _ := md.Get(users).([]interface{}); len(v) > 0 {
+	if auths := mdata.GetStrings(md, users); len(auths) > 0 {
-		for _, auth := range v {
+		auth := auths[0]
-			if s, _ := auth.(string); s != "" {
+		ss := strings.SplitN(auth, ":", 2)
-				ss := strings.SplitN(s, ":", 2)
+		if len(ss) == 1 {
-				if len(ss) == 1 {
+			method = ss[0]
-					method = ss[0]
+		} else {
-				} else {
+			method, password = ss[0], ss[1]
-					method, password = ss[0], ss[1]
-				}
-			}
 		}
 	}
-	h.md.cipher, err = ss.ShadowCipher(method, password, md.GetString(key))
+	h.md.cipher, err = ss.ShadowCipher(method, password, mdata.GetString(md, key))
 	if err != nil {
 		return
 	}
 
-	h.md.readTimeout = md.GetDuration(readTimeout)
+	h.md.readTimeout = mdata.GetDuration(md, readTimeout)
-	h.md.retryCount = md.GetInt(retryCount)
+	h.md.retryCount = mdata.GetInt(md, retryCount)
 
-	h.md.bufferSize = md.GetInt(bufferSize)
+	if bs := mdata.GetInt(md, bufferSize); bs > 0 {
-	if h.md.bufferSize > 0 {
+		h.md.bufferSize = int(math.Min(math.Max(float64(bs), 512), 64*1024))
-		if h.md.bufferSize < 512 {
-			h.md.bufferSize = 512 // min buffer size
-		}
-		if h.md.bufferSize > 65*1024 {
-			h.md.bufferSize = 65 * 1024 // max buffer size
-		}
 	} else {
-		h.md.bufferSize = 1024 // default buffer size
+		h.md.bufferSize = 1024
 	}
 	return
 }

pkg/handler/tap/conn.go

@@ -0,0 +1,17 @@
+package tap
+
+import "net"
+
+type packetConn struct {
+	net.Conn
+}
+
+func (c *packetConn) ReadFrom(b []byte) (n int, addr net.Addr, err error) {
+	n, err = c.Read(b)
+	addr = c.Conn.RemoteAddr()
+	return
+}
+
+func (c *packetConn) WriteTo(b []byte, addr net.Addr) (n int, err error) {
+	return c.Write(b)
+}

pkg/handler/tap/handler.go

@@ -0,0 +1,331 @@
+package tap
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net"
+	"os"
+	"sync"
+	"time"
+
+	"github.com/go-gost/gost/pkg/bypass"
+	"github.com/go-gost/gost/pkg/chain"
+	"github.com/go-gost/gost/pkg/common/bufpool"
+	"github.com/go-gost/gost/pkg/handler"
+	tap_util "github.com/go-gost/gost/pkg/internal/util/tap"
+	"github.com/go-gost/gost/pkg/logger"
+	md "github.com/go-gost/gost/pkg/metadata"
+	"github.com/go-gost/gost/pkg/registry"
+	"github.com/shadowsocks/go-shadowsocks2/shadowaead"
+	"github.com/songgao/water/waterutil"
+	"github.com/xtaci/tcpraw"
+)
+
+func init() {
+	registry.RegisterHandler("tap", NewHandler)
+}
+
+type tapHandler struct {
+	group  *chain.NodeGroup
+	chain  *chain.Chain
+	bypass bypass.Bypass
+	routes sync.Map
+	exit   chan struct{}
+	logger logger.Logger
+	md     metadata
+}
+
+func NewHandler(opts ...handler.Option) handler.Handler {
+	options := &handler.Options{}
+	for _, opt := range opts {
+		opt(options)
+	}
+
+	return &tapHandler{
+		bypass: options.Bypass,
+		exit:   make(chan struct{}, 1),
+		logger: options.Logger,
+	}
+}
+
+func (h *tapHandler) Init(md md.Metadata) (err error) {
+	return h.parseMetadata(md)
+}
+
+// implements chain.Chainable interface
+func (h *tapHandler) WithChain(chain *chain.Chain) {
+	h.chain = chain
+}
+
+// Forward implements handler.Forwarder.
+func (h *tapHandler) Forward(group *chain.NodeGroup) {
+	h.group = group
+}
+
+func (h *tapHandler) Handle(ctx context.Context, conn net.Conn) {
+	defer os.Exit(0)
+	defer conn.Close()
+
+	cc, ok := conn.(*tap_util.Conn)
+	if !ok || cc.Config() == nil {
+		h.logger.Error("invalid connection")
+		return
+	}
+
+	start := time.Now()
+	h.logger = h.logger.WithFields(map[string]interface{}{
+		"remote": conn.RemoteAddr().String(),
+		"local":  conn.LocalAddr().String(),
+	})
+
+	h.logger.Infof("%s <> %s", conn.RemoteAddr(), conn.LocalAddr())
+	defer func() {
+		h.logger.WithFields(map[string]interface{}{
+			"duration": time.Since(start),
+		}).Infof("%s >< %s", conn.RemoteAddr(), conn.LocalAddr())
+	}()
+
+	network := "udp"
+	var raddr net.Addr
+	var err error
+
+	target := h.group.Next()
+	if target != nil {
+		raddr, err = net.ResolveUDPAddr(network, target.Addr())
+		if err != nil {
+			h.logger.Error(err)
+			return
+		}
+		h.logger = h.logger.WithFields(map[string]interface{}{
+			"dst": fmt.Sprintf("%s/%s", raddr.String(), raddr.Network()),
+		})
+		h.logger.Infof("%s >> %s", conn.RemoteAddr(), target.Addr())
+	}
+
+	h.handleLoop(ctx, conn, raddr, cc.Config())
+}
+
+func (h *tapHandler) handleLoop(ctx context.Context, conn net.Conn, addr net.Addr, config *tap_util.Config) {
+	var tempDelay time.Duration
+	for {
+		err := func() error {
+			var err error
+			var pc net.PacketConn
+			// fake tcp mode will be ignored when the client specifies a chain.
+			if addr != nil && !h.chain.IsEmpty() {
+				r := (&chain.Router{}).
+					WithChain(h.chain).
+					WithRetry(h.md.retryCount).
+					WithLogger(h.logger)
+				cc, err := r.Dial(ctx, addr.Network(), addr.String())
+				if err != nil {
+					return err
+				}
+				pc = &packetConn{cc}
+			} else {
+				if h.md.tcpMode {
+					if addr != nil {
+						pc, err = tcpraw.Dial("tcp", addr.String())
+					} else {
+						pc, err = tcpraw.Listen("tcp", conn.LocalAddr().String())
+					}
+				} else {
+					laddr, _ := net.ResolveUDPAddr("udp", conn.LocalAddr().String())
+					pc, err = net.ListenUDP("udp", laddr)
+				}
+			}
+			if err != nil {
+				return err
+			}
+
+			if h.md.cipher != nil {
+				pc = h.md.cipher.PacketConn(pc)
+			}
+
+			return h.transport(conn, pc, addr)
+		}()
+		if err != nil {
+			h.logger.Error(err)
+		}
+
+		select {
+		case <-h.exit:
+			return
+		default:
+		}
+
+		if err != nil {
+			if tempDelay == 0 {
+				tempDelay = 1000 * time.Millisecond
+			} else {
+				tempDelay *= 2
+			}
+			if max := 6 * time.Second; tempDelay > max {
+				tempDelay = max
+			}
+			time.Sleep(tempDelay)
+			continue
+		}
+		tempDelay = 0
+	}
+
+}
+
+func (h *tapHandler) transport(tap net.Conn, conn net.PacketConn, raddr net.Addr) error {
+	errc := make(chan error, 1)
+
+	go func() {
+		for {
+			err := func() error {
+				b := bufpool.Get(h.md.bufferSize)
+				defer bufpool.Put(b)
+
+				n, err := tap.Read(b)
+				if err != nil {
+					select {
+					case h.exit <- struct{}{}:
+					default:
+					}
+					return err
+				}
+
+				src := waterutil.MACSource(b[:n])
+				dst := waterutil.MACDestination(b[:n])
+				eType := etherType(waterutil.MACEthertype(b[:n]))
+
+				h.logger.Debugf("%s >> %s %s %d", src, dst, eType, n)
+
+				// client side, deliver frame directly.
+				if raddr != nil {
+					_, err := conn.WriteTo(b[:n], raddr)
+					return err
+				}
+
+				// server side, broadcast.
+				if waterutil.IsBroadcast(dst) {
+					go h.routes.Range(func(k, v interface{}) bool {
+						conn.WriteTo(b[:n], v.(net.Addr))
+						return true
+					})
+					return nil
+				}
+
+				var addr net.Addr
+				if v, ok := h.routes.Load(hwAddrToTapRouteKey(dst)); ok {
+					addr = v.(net.Addr)
+				}
+				if addr == nil {
+					h.logger.Warnf("no route for %s -> %s %s %d", src, dst, eType, n)
+					return nil
+				}
+
+				if _, err := conn.WriteTo(b[:n], addr); err != nil {
+					return err
+				}
+
+				return nil
+			}()
+
+			if err != nil {
+				errc <- err
+				return
+			}
+		}
+	}()
+
+	go func() {
+		for {
+			err := func() error {
+				b := bufpool.Get(h.md.bufferSize)
+				defer bufpool.Put(b)
+
+				n, addr, err := conn.ReadFrom(b)
+				if err != nil &&
+					err != shadowaead.ErrShortPacket {
+					return err
+				}
+
+				src := waterutil.MACSource(b[:n])
+				dst := waterutil.MACDestination(b[:n])
+				eType := etherType(waterutil.MACEthertype(b[:n]))
+
+				h.logger.Debugf("%s >> %s %s %d", src, dst, eType, n)
+
+				// client side, deliver frame to tap device.
+				if raddr != nil {
+					_, err := tap.Write(b[:n])
+					return err
+				}
+
+				// server side, record route.
+				rkey := hwAddrToTapRouteKey(src)
+				if actual, loaded := h.routes.LoadOrStore(rkey, addr); loaded {
+					if actual.(net.Addr).String() != addr.String() {
+						h.logger.Debugf("update route: %s -> %s (old %s)",
+							src, addr, actual.(net.Addr))
+						h.routes.Store(rkey, addr)
+					}
+				} else {
+					h.logger.Debugf("new route: %s -> %s", src, addr)
+				}
+
+				if waterutil.IsBroadcast(dst) {
+					go h.routes.Range(func(k, v interface{}) bool {
+						if k.(tapRouteKey) != rkey {
+							conn.WriteTo(b[:n], v.(net.Addr))
+						}
+						return true
+					})
+				}
+
+				if v, ok := h.routes.Load(hwAddrToTapRouteKey(dst)); ok {
+					h.logger.Debugf("find route: %s -> %s", dst, v)
+					_, err := conn.WriteTo(b[:n], v.(net.Addr))
+					return err
+				}
+
+				if _, err := tap.Write(b[:n]); err != nil {
+					select {
+					case h.exit <- struct{}{}:
+					default:
+					}
+					return err
+				}
+				return nil
+			}()
+
+			if err != nil {
+				errc <- err
+				return
+			}
+		}
+	}()
+
+	err := <-errc
+	if err != nil && err == io.EOF {
+		err = nil
+	}
+	return err
+}
+
+var mEtherTypes = map[waterutil.Ethertype]string{
+	waterutil.IPv4: "ip",
+	waterutil.ARP:  "arp",
+	waterutil.RARP: "rarp",
+	waterutil.IPv6: "ip6",
+}
+
+func etherType(et waterutil.Ethertype) string {
+	if s, ok := mEtherTypes[et]; ok {
+		return s
+	}
+	return fmt.Sprintf("unknown(%v)", et)
+}
+
+type tapRouteKey [6]byte
+
+func hwAddrToTapRouteKey(addr net.HardwareAddr) (key tapRouteKey) {
+	copy(key[:], addr)
+	return
+}

pkg/handler/tap/metadata.go

@@ -0,0 +1,50 @@
+package tap
+
+import (
+	"strings"
+
+	"github.com/go-gost/gost/pkg/common/util/ss"
+	mdata "github.com/go-gost/gost/pkg/metadata"
+	"github.com/shadowsocks/go-shadowsocks2/core"
+)
+
+type metadata struct {
+	cipher     core.Cipher
+	retryCount int
+	tcpMode    bool
+	bufferSize int
+}
+
+func (h *tapHandler) parseMetadata(md mdata.Metadata) (err error) {
+	const (
+		users       = "users"
+		key         = "key"
+		readTimeout = "readTimeout"
+		retryCount  = "retry"
+		tcpMode     = "tcp"
+		bufferSize  = "bufferSize"
+	)
+
+	var method, password string
+	if auths := mdata.GetStrings(md, users); len(auths) > 0 {
+		auth := auths[0]
+		ss := strings.SplitN(auth, ":", 2)
+		if len(ss) == 1 {
+			method = ss[0]
+		} else {
+			method, password = ss[0], ss[1]
+		}
+	}
+	h.md.cipher, err = ss.ShadowCipher(method, password, mdata.GetString(md, key))
+	if err != nil {
+		return
+	}
+	h.md.retryCount = mdata.GetInt(md, retryCount)
+	h.md.tcpMode = mdata.GetBool(md, tcpMode)
+
+	h.md.bufferSize = mdata.GetInt(md, bufferSize)
+	if h.md.bufferSize <= 0 {
+		h.md.bufferSize = 1024
+	}
+	return
+}

pkg/handler/tun/conn.go

@@ -0,0 +1,17 @@
+package tun
+
+import "net"
+
+type packetConn struct {
+	net.Conn
+}
+
+func (c *packetConn) ReadFrom(b []byte) (n int, addr net.Addr, err error) {
+	n, err = c.Read(b)
+	addr = c.Conn.RemoteAddr()
+	return
+}
+
+func (c *packetConn) WriteTo(b []byte, addr net.Addr) (n int, err error) {
+	return c.Write(b)
+}

pkg/handler/tun/handler.go

@@ -0,0 +1,380 @@
+package tun
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net"
+	"os"
+	"sync"
+	"time"
+
+	"github.com/go-gost/gost/pkg/bypass"
+	"github.com/go-gost/gost/pkg/chain"
+	"github.com/go-gost/gost/pkg/common/bufpool"
+	"github.com/go-gost/gost/pkg/handler"
+	tun_util "github.com/go-gost/gost/pkg/internal/util/tun"
+	"github.com/go-gost/gost/pkg/logger"
+	md "github.com/go-gost/gost/pkg/metadata"
+	"github.com/go-gost/gost/pkg/registry"
+	"github.com/shadowsocks/go-shadowsocks2/shadowaead"
+	"github.com/songgao/water/waterutil"
+	"github.com/xtaci/tcpraw"
+	"golang.org/x/net/ipv4"
+	"golang.org/x/net/ipv6"
+)
+
+func init() {
+	registry.RegisterHandler("tun", NewHandler)
+}
+
+type tunHandler struct {
+	group  *chain.NodeGroup
+	chain  *chain.Chain
+	bypass bypass.Bypass
+	routes sync.Map
+	exit   chan struct{}
+	logger logger.Logger
+	md     metadata
+}
+
+func NewHandler(opts ...handler.Option) handler.Handler {
+	options := &handler.Options{}
+	for _, opt := range opts {
+		opt(options)
+	}
+
+	return &tunHandler{
+		bypass: options.Bypass,
+		exit:   make(chan struct{}, 1),
+		logger: options.Logger,
+	}
+}
+
+func (h *tunHandler) Init(md md.Metadata) (err error) {
+	return h.parseMetadata(md)
+}
+
+// implements chain.Chainable interface
+func (h *tunHandler) WithChain(chain *chain.Chain) {
+	h.chain = chain
+}
+
+// Forward implements handler.Forwarder.
+func (h *tunHandler) Forward(group *chain.NodeGroup) {
+	h.group = group
+}
+
+func (h *tunHandler) Handle(ctx context.Context, conn net.Conn) {
+	defer os.Exit(0)
+	defer conn.Close()
+
+	cc, ok := conn.(*tun_util.Conn)
+	if !ok || cc.Config() == nil {
+		h.logger.Error("invalid connection")
+		return
+	}
+
+	start := time.Now()
+	h.logger = h.logger.WithFields(map[string]interface{}{
+		"remote": conn.RemoteAddr().String(),
+		"local":  conn.LocalAddr().String(),
+	})
+
+	h.logger.Infof("%s <> %s", conn.RemoteAddr(), conn.LocalAddr())
+	defer func() {
+		h.logger.WithFields(map[string]interface{}{
+			"duration": time.Since(start),
+		}).Infof("%s >< %s", conn.RemoteAddr(), conn.LocalAddr())
+	}()
+
+	network := "udp"
+	var raddr net.Addr
+	var err error
+
+	target := h.group.Next()
+	if target != nil {
+		raddr, err = net.ResolveUDPAddr(network, target.Addr())
+		if err != nil {
+			h.logger.Error(err)
+			return
+		}
+		h.logger = h.logger.WithFields(map[string]interface{}{
+			"dst": fmt.Sprintf("%s/%s", raddr.String(), raddr.Network()),
+		})
+		h.logger.Infof("%s >> %s", conn.RemoteAddr(), target.Addr())
+	}
+
+	h.handleLoop(ctx, conn, raddr, cc.Config())
+}
+
+func (h *tunHandler) handleLoop(ctx context.Context, conn net.Conn, addr net.Addr, config *tun_util.Config) {
+	var tempDelay time.Duration
+	for {
+		err := func() error {
+			var err error
+			var pc net.PacketConn
+			// fake tcp mode will be ignored when the client specifies a chain.
+			if addr != nil && !h.chain.IsEmpty() {
+				r := (&chain.Router{}).
+					WithChain(h.chain).
+					WithRetry(h.md.retryCount).
+					WithLogger(h.logger)
+				cc, err := r.Dial(ctx, addr.Network(), addr.String())
+				if err != nil {
+					return err
+				}
+				pc = &packetConn{cc}
+			} else {
+				if h.md.tcpMode {
+					if addr != nil {
+						pc, err = tcpraw.Dial("tcp", addr.String())
+					} else {
+						pc, err = tcpraw.Listen("tcp", conn.LocalAddr().String())
+					}
+				} else {
+					laddr, _ := net.ResolveUDPAddr("udp", conn.LocalAddr().String())
+					pc, err = net.ListenUDP("udp", laddr)
+				}
+			}
+			if err != nil {
+				return err
+			}
+
+			if h.md.cipher != nil {
+				pc = h.md.cipher.PacketConn(pc)
+			}
+
+			return h.transport(conn, pc, addr)
+		}()
+		if err != nil {
+			h.logger.Error(err)
+		}
+
+		select {
+		case <-h.exit:
+			return
+		default:
+		}
+
+		if err != nil {
+			if tempDelay == 0 {
+				tempDelay = 1000 * time.Millisecond
+			} else {
+				tempDelay *= 2
+			}
+			if max := 6 * time.Second; tempDelay > max {
+				tempDelay = max
+			}
+			time.Sleep(tempDelay)
+			continue
+		}
+		tempDelay = 0
+	}
+
+}
+
+func (h *tunHandler) transport(tun net.Conn, conn net.PacketConn, raddr net.Addr) error {
+	errc := make(chan error, 1)
+
+	go func() {
+		for {
+			err := func() error {
+				b := bufpool.Get(h.md.bufferSize)
+				defer bufpool.Put(b)
+
+				n, err := tun.Read(b)
+				if err != nil {
+					select {
+					case h.exit <- struct{}{}:
+					default:
+					}
+					return err
+				}
+
+				var src, dst net.IP
+				if waterutil.IsIPv4(b[:n]) {
+					header, err := ipv4.ParseHeader(b[:n])
+					if err != nil {
+						h.logger.Error(err)
+						return nil
+					}
+					h.logger.Debugf("%s >> %s %-4s %d/%-4d %-4x %d",
+						header.Src, header.Dst, ipProtocol(waterutil.IPv4Protocol(b[:n])),
+						header.Len, header.TotalLen, header.ID, header.Flags)
+
+					src, dst = header.Src, header.Dst
+				} else if waterutil.IsIPv6(b[:n]) {
+					header, err := ipv6.ParseHeader(b[:n])
+					if err != nil {
+						h.logger.Warn(err)
+						return nil
+					}
+					h.logger.Debugf("%s >> %s %s %d %d",
+						header.Src, header.Dst,
+						ipProtocol(waterutil.IPProtocol(header.NextHeader)),
+						header.PayloadLen, header.TrafficClass)
+
+					src, dst = header.Src, header.Dst
+				} else {
+					h.logger.Warn("unknown packet, discarded")
+					return nil
+				}
+
+				// client side, deliver packet directly.
+				if raddr != nil {
+					_, err := conn.WriteTo(b[:n], raddr)
+					return err
+				}
+
+				addr := h.findRouteFor(dst)
+				if addr == nil {
+					h.logger.Warnf("no route for %s -> %s", src, dst)
+					return nil
+				}
+
+				h.logger.Debugf("find route: %s -> %s", dst, addr)
+
+				if _, err := conn.WriteTo(b[:n], addr); err != nil {
+					return err
+				}
+				return nil
+			}()
+
+			if err != nil {
+				errc <- err
+				return
+			}
+		}
+	}()
+
+	go func() {
+		for {
+			err := func() error {
+				b := bufpool.Get(h.md.bufferSize)
+				defer bufpool.Put(b)
+
+				n, addr, err := conn.ReadFrom(b)
+				if err != nil &&
+					err != shadowaead.ErrShortPacket {
+					return err
+				}
+
+				var src, dst net.IP
+				if waterutil.IsIPv4(b[:n]) {
+					header, err := ipv4.ParseHeader(b[:n])
+					if err != nil {
+						h.logger.Warn(err)
+						return nil
+					}
+
+					h.logger.Debugf("%s >> %s %-4s %d/%-4d %-4x %d",
+						header.Src, header.Dst, ipProtocol(waterutil.IPv4Protocol(b[:n])),
+						header.Len, header.TotalLen, header.ID, header.Flags)
+
+					src, dst = header.Src, header.Dst
+				} else if waterutil.IsIPv6(b[:n]) {
+					header, err := ipv6.ParseHeader(b[:n])
+					if err != nil {
+						h.logger.Warn(err)
+						return nil
+					}
+
+					h.logger.Debugf("%s > %s %s %d %d",
+						header.Src, header.Dst,
+						ipProtocol(waterutil.IPProtocol(header.NextHeader)),
+						header.PayloadLen, header.TrafficClass)
+
+					src, dst = header.Src, header.Dst
+				} else {
+					h.logger.Warn("unknown packet, discarded")
+					return nil
+				}
+
+				// client side, deliver packet to tun device.
+				if raddr != nil {
+					_, err := tun.Write(b[:n])
+					return err
+				}
+
+				rkey := ipToTunRouteKey(src)
+				if actual, loaded := h.routes.LoadOrStore(rkey, addr); loaded {
+					if actual.(net.Addr).String() != addr.String() {
+						h.logger.Debugf("update route: %s -> %s (old %s)",
+							src, addr, actual.(net.Addr))
+						h.routes.Store(rkey, addr)
+					}
+				} else {
+					h.logger.Warnf("no route for %s -> %s", src, addr)
+				}
+
+				if addr := h.findRouteFor(dst); addr != nil {
+					h.logger.Debugf("find route: %s -> %s", dst, addr)
+
+					_, err := conn.WriteTo(b[:n], addr)
+					return err
+				}
+
+				if _, err := tun.Write(b[:n]); err != nil {
+					select {
+					case h.exit <- struct{}{}:
+					default:
+					}
+					return err
+				}
+				return nil
+			}()
+
+			if err != nil {
+				errc <- err
+				return
+			}
+		}
+	}()
+
+	err := <-errc
+	if err != nil && err == io.EOF {
+		err = nil
+	}
+	return err
+}
+
+func (h *tunHandler) findRouteFor(dst net.IP, routes ...tun_util.Route) net.Addr {
+	if v, ok := h.routes.Load(ipToTunRouteKey(dst)); ok {
+		return v.(net.Addr)
+	}
+	for _, route := range routes {
+		if route.Net.Contains(dst) && route.Gateway != nil {
+			if v, ok := h.routes.Load(ipToTunRouteKey(route.Gateway)); ok {
+				return v.(net.Addr)
+			}
+		}
+	}
+	return nil
+}
+
+var mIPProts = map[waterutil.IPProtocol]string{
+	waterutil.HOPOPT:     "HOPOPT",
+	waterutil.ICMP:       "ICMP",
+	waterutil.IGMP:       "IGMP",
+	waterutil.GGP:        "GGP",
+	waterutil.TCP:        "TCP",
+	waterutil.UDP:        "UDP",
+	waterutil.IPv6_Route: "IPv6-Route",
+	waterutil.IPv6_Frag:  "IPv6-Frag",
+	waterutil.IPv6_ICMP:  "IPv6-ICMP",
+}
+
+func ipProtocol(p waterutil.IPProtocol) string {
+	if v, ok := mIPProts[p]; ok {
+		return v
+	}
+	return fmt.Sprintf("unknown(%d)", p)
+}
+
+type tunRouteKey [16]byte
+
+func ipToTunRouteKey(ip net.IP) (key tunRouteKey) {
+	copy(key[:], ip.To16())
+	return
+}

pkg/handler/tun/metadata.go

@@ -0,0 +1,50 @@
+package tun
+
+import (
+	"strings"
+
+	"github.com/go-gost/gost/pkg/common/util/ss"
+	mdata "github.com/go-gost/gost/pkg/metadata"
+	"github.com/shadowsocks/go-shadowsocks2/core"
+)
+
+type metadata struct {
+	cipher     core.Cipher
+	retryCount int
+	tcpMode    bool
+	bufferSize int
+}
+
+func (h *tunHandler) parseMetadata(md mdata.Metadata) (err error) {
+	const (
+		users       = "users"
+		key         = "key"
+		readTimeout = "readTimeout"
+		retryCount  = "retry"
+		tcpMode     = "tcp"
+		bufferSize  = "bufferSize"
+	)
+
+	var method, password string
+	if auths := mdata.GetStrings(md, users); len(auths) > 0 {
+		auth := auths[0]
+		ss := strings.SplitN(auth, ":", 2)
+		if len(ss) == 1 {
+			method = ss[0]
+		} else {
+			method, password = ss[0], ss[1]
+		}
+	}
+	h.md.cipher, err = ss.ShadowCipher(method, password, mdata.GetString(md, key))
+	if err != nil {
+		return
+	}
+	h.md.retryCount = mdata.GetInt(md, retryCount)
+	h.md.tcpMode = mdata.GetBool(md, tcpMode)
+
+	h.md.bufferSize = mdata.GetInt(md, bufferSize)
+	if h.md.bufferSize <= 0 {
+		h.md.bufferSize = 1024
+	}
+	return
+}

pkg/internal/util/tap/config.go

@@ -0,0 +1,9 @@
+package tap
+
+type Config struct {
+	Name    string
+	Net     string
+	MTU     int
+	Routes  []string
+	Gateway string
+}

pkg/internal/util/tap/conn.go

@@ -0,0 +1,61 @@
+package tap
+
+import (
+	"errors"
+	"net"
+	"time"
+
+	"github.com/songgao/water"
+)
+
+type Conn struct {
+	config *Config
+	ifce   *water.Interface
+	laddr  net.Addr
+	raddr  net.Addr
+}
+
+func NewConn(config *Config, ifce *water.Interface, laddr, raddr net.Addr) *Conn {
+	return &Conn{
+		config: config,
+		ifce:   ifce,
+		laddr:  laddr,
+		raddr:  raddr,
+	}
+}
+
+func (c *Conn) Config() *Config {
+	return c.config
+}
+
+func (c *Conn) Read(b []byte) (n int, err error) {
+	return c.ifce.Read(b)
+}
+
+func (c *Conn) Write(b []byte) (n int, err error) {
+	return c.ifce.Write(b)
+}
+
+func (c *Conn) Close() (err error) {
+	return c.ifce.Close()
+}
+
+func (c *Conn) LocalAddr() net.Addr {
+	return c.laddr
+}
+
+func (c *Conn) RemoteAddr() net.Addr {
+	return c.raddr
+}
+
+func (c *Conn) SetDeadline(t time.Time) error {
+	return &net.OpError{Op: "set", Net: "tuntap", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
+}
+
+func (c *Conn) SetReadDeadline(t time.Time) error {
+	return &net.OpError{Op: "set", Net: "tuntap", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
+}
+
+func (c *Conn) SetWriteDeadline(t time.Time) error {
+	return &net.OpError{Op: "set", Net: "tuntap", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
+}

pkg/internal/util/tun/config.go

@@ -0,0 +1,19 @@
+package tun
+
+import "net"
+
+// Route is an IP routing entry
+type Route struct {
+	Net     net.IPNet
+	Gateway net.IP
+}
+
+type Config struct {
+	Name string
+	Net  string
+	// peer addr of point-to-point on MacOS
+	Peer    string
+	MTU     int
+	Gateway string
+	Routes  []Route
+}

pkg/internal/util/tun/conn.go

@@ -0,0 +1,61 @@
+package tun
+
+import (
+	"errors"
+	"net"
+	"time"
+
+	"github.com/songgao/water"
+)
+
+type Conn struct {
+	config *Config
+	ifce   *water.Interface
+	laddr  net.Addr
+	raddr  net.Addr
+}
+
+func NewConn(config *Config, ifce *water.Interface, laddr, raddr net.Addr) *Conn {
+	return &Conn{
+		config: config,
+		ifce:   ifce,
+		laddr:  laddr,
+		raddr:  raddr,
+	}
+}
+
+func (c *Conn) Config() *Config {
+	return c.config
+}
+
+func (c *Conn) Read(b []byte) (n int, err error) {
+	return c.ifce.Read(b)
+}
+
+func (c *Conn) Write(b []byte) (n int, err error) {
+	return c.ifce.Write(b)
+}
+
+func (c *Conn) Close() (err error) {
+	return c.ifce.Close()
+}
+
+func (c *Conn) LocalAddr() net.Addr {
+	return c.laddr
+}
+
+func (c *Conn) RemoteAddr() net.Addr {
+	return c.raddr
+}
+
+func (c *Conn) SetDeadline(t time.Time) error {
+	return &net.OpError{Op: "set", Net: "tuntap", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
+}
+
+func (c *Conn) SetReadDeadline(t time.Time) error {
+	return &net.OpError{Op: "set", Net: "tuntap", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
+}
+
+func (c *Conn) SetWriteDeadline(t time.Time) error {
+	return &net.OpError{Op: "set", Net: "tuntap", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
+}

pkg/listener/http2/h2/metadata.go

@@ -4,7 +4,7 @@ import (
 	"crypto/tls"
 
 	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 const (
@@ -17,7 +17,7 @@ type metadata struct {
 	backlog   int
 }
 
-func (l *h2Listener) parseMetadata(md md.Metadata) (err error) {
+func (l *h2Listener) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		path     = "path"
 		certFile = "certFile"
@@ -27,19 +27,19 @@ func (l *h2Listener) parseMetadata(md md.Metadata) (err error) {
 	)
 
 	l.md.tlsConfig, err = tls_util.LoadServerConfig(
-		md.GetString(certFile),
+		mdata.GetString(md, certFile),
-		md.GetString(keyFile),
+		mdata.GetString(md, keyFile),
-		md.GetString(caFile),
+		mdata.GetString(md, caFile),
 	)
 	if err != nil {
 		return
 	}
 
-	l.md.backlog = md.GetInt(backlog)
+	l.md.backlog = mdata.GetInt(md, backlog)
 	if l.md.backlog <= 0 {
 		l.md.backlog = defaultBacklog
 	}
 
-	l.md.path = md.GetString(path)
+	l.md.path = mdata.GetString(md, path)
 	return
 }

pkg/listener/http2/metadata.go

@@ -6,7 +6,7 @@ import (
 	"time"
 
 	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 const (
@@ -25,7 +25,7 @@ type metadata struct {
 	backlog           int
 }
 
-func (l *http2Listener) parseMetadata(md md.Metadata) (err error) {
+func (l *http2Listener) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		path              = "path"
 		certFile          = "certFile"
@@ -39,15 +39,15 @@ func (l *http2Listener) parseMetadata(md md.Metadata) (err error) {
 	)
 
 	l.md.tlsConfig, err = tls_util.LoadServerConfig(
-		md.GetString(certFile),
+		mdata.GetString(md, certFile),
-		md.GetString(keyFile),
+		mdata.GetString(md, keyFile),
-		md.GetString(caFile),
+		mdata.GetString(md, caFile),
 	)
 	if err != nil {
 		return
 	}
 
-	l.md.backlog = md.GetInt(backlog)
+	l.md.backlog = mdata.GetInt(md, backlog)
 	if l.md.backlog <= 0 {
 		l.md.backlog = defaultBacklog
 	}

pkg/listener/kcp/metadata.go

@@ -4,7 +4,7 @@ import (
 	"encoding/json"
 
 	kcp_util "github.com/go-gost/gost/pkg/common/util/kcp"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 const (
@@ -16,19 +16,13 @@ type metadata struct {
 	backlog int
 }
 
-func (l *kcpListener) parseMetadata(md md.Metadata) (err error) {
+func (l *kcpListener) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		backlog = "backlog"
 		config  = "config"
 	)
 
-	if mm, _ := md.Get(config).(map[interface{}]interface{}); len(mm) > 0 {
+	if m := mdata.GetStringMap(md, config); len(m) > 0 {
-		m := make(map[string]interface{})
-		for k, v := range mm {
-			if sk, ok := k.(string); ok {
-				m[sk] = v
-			}
-		}
 		b, err := json.Marshal(m)
 		if err != nil {
 			return err
@@ -44,7 +38,7 @@ func (l *kcpListener) parseMetadata(md md.Metadata) (err error) {
 		l.md.config = kcp_util.DefaultConfig
 	}
 
-	l.md.backlog = md.GetInt(backlog)
+	l.md.backlog = mdata.GetInt(md, backlog)
 	if l.md.backlog <= 0 {
 		l.md.backlog = defaultBacklog
 	}

pkg/listener/quic/metadata.go

@@ -5,7 +5,7 @@ import (
 	"time"
 
 	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 const (
@@ -22,7 +22,7 @@ type metadata struct {
 	backlog   int
 }
 
-func (l *quicListener) parseMetadata(md md.Metadata) (err error) {
+func (l *quicListener) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		keepAlive        = "keepAlive"
 		handshakeTimeout = "handshakeTimeout"
@@ -37,26 +37,26 @@ func (l *quicListener) parseMetadata(md md.Metadata) (err error) {
 	)
 
 	l.md.tlsConfig, err = tls_util.LoadServerConfig(
-		md.GetString(certFile),
+		mdata.GetString(md, certFile),
-		md.GetString(keyFile),
+		mdata.GetString(md, keyFile),
-		md.GetString(caFile),
+		mdata.GetString(md, caFile),
 	)
 
 	if err != nil {
 		return
 	}
-	l.md.backlog = md.GetInt(backlog)
+	l.md.backlog = mdata.GetInt(md, backlog)
 	if l.md.backlog <= 0 {
 		l.md.backlog = defaultBacklog
 	}
 
-	if key := md.GetString(cipherKey); key != "" {
+	if key := mdata.GetString(md, cipherKey); key != "" {
 		l.md.cipherKey = []byte(key)
 	}
 
-	l.md.keepAlive = md.GetBool(keepAlive)
+	l.md.keepAlive = mdata.GetBool(md, keepAlive)
-	l.md.handshakeTimeout = md.GetDuration(handshakeTimeout)
+	l.md.handshakeTimeout = mdata.GetDuration(md, handshakeTimeout)
-	l.md.maxIdleTimeout = md.GetDuration(maxIdleTimeout)
+	l.md.maxIdleTimeout = mdata.GetDuration(md, maxIdleTimeout)
 
 	return
 }

pkg/listener/redirect/udp/metadata.go

@@ -3,7 +3,7 @@ package udp
 import (
 	"time"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 const (
@@ -16,18 +16,18 @@ type metadata struct {
 	readBufferSize int
 }
 
-func (l *redirectListener) parseMetadata(md md.Metadata) (err error) {
+func (l *redirectListener) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		ttl            = "ttl"
 		readBufferSize = "readBufferSize"
 	)
 
-	l.md.ttl = md.GetDuration(ttl)
+	l.md.ttl = mdata.GetDuration(md, ttl)
 	if l.md.ttl <= 0 {
 		l.md.ttl = defaultTTL
 	}
 
-	l.md.readBufferSize = md.GetInt(readBufferSize)
+	l.md.readBufferSize = mdata.GetInt(md, readBufferSize)
 	if l.md.readBufferSize <= 0 {
 		l.md.readBufferSize = defaultReadBufferSize
 	}

pkg/listener/rtcp/metadata.go

@@ -3,7 +3,7 @@ package rtcp
 import (
 	"time"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 const (
@@ -17,17 +17,17 @@ type metadata struct {
 	retryCount int
 }
 
-func (l *rtcpListener) parseMetadata(md md.Metadata) (err error) {
+func (l *rtcpListener) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		enableMux  = "mux"
 		backlog    = "backlog"
 		retryCount = "retry"
 	)
 
-	l.md.enableMux = md.GetBool(enableMux)
+	l.md.enableMux = mdata.GetBool(md, enableMux)
-	l.md.retryCount = md.GetInt(retryCount)
+	l.md.retryCount = mdata.GetInt(md, retryCount)
 
-	l.md.backlog = md.GetInt(backlog)
+	l.md.backlog = mdata.GetInt(md, backlog)
 	if l.md.backlog <= 0 {
 		l.md.backlog = defaultBacklog
 	}

pkg/listener/rudp/metadata.go

@@ -3,7 +3,7 @@ package rudp
 import (
 	"time"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 const (
@@ -21,7 +21,7 @@ type metadata struct {
 	retryCount     int
 }
 
-func (l *rudpListener) parseMetadata(md md.Metadata) (err error) {
+func (l *rudpListener) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		ttl            = "ttl"
 		readBufferSize = "readBufferSize"
@@ -30,25 +30,25 @@ func (l *rudpListener) parseMetadata(md md.Metadata) (err error) {
 		retryCount     = "retry"
 	)
 
-	l.md.ttl = md.GetDuration(ttl)
+	l.md.ttl = mdata.GetDuration(md, ttl)
 	if l.md.ttl <= 0 {
 		l.md.ttl = defaultTTL
 	}
-	l.md.readBufferSize = md.GetInt(readBufferSize)
+	l.md.readBufferSize = mdata.GetInt(md, readBufferSize)
 	if l.md.readBufferSize <= 0 {
 		l.md.readBufferSize = defaultReadBufferSize
 	}
 
-	l.md.readQueueSize = md.GetInt(readQueueSize)
+	l.md.readQueueSize = mdata.GetInt(md, readQueueSize)
 	if l.md.readQueueSize <= 0 {
 		l.md.readQueueSize = defaultReadQueueSize
 	}
 
-	l.md.backlog = md.GetInt(backlog)
+	l.md.backlog = mdata.GetInt(md, backlog)
 	if l.md.backlog <= 0 {
 		l.md.backlog = defaultBacklog
 	}
 
-	l.md.retryCount = md.GetInt(retryCount)
+	l.md.retryCount = mdata.GetInt(md, retryCount)
 	return
 }

pkg/listener/ssh/metadata.go

@@ -7,7 +7,7 @@ import (
 	"github.com/go-gost/gost/pkg/auth"
 	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
 	ssh_util "github.com/go-gost/gost/pkg/internal/util/ssh"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 	"golang.org/x/crypto/ssh"
 )
 
@@ -22,7 +22,7 @@ type metadata struct {
 	backlog        int
 }
 
-func (l *sshListener) parseMetadata(md md.Metadata) (err error) {
+func (l *sshListener) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		users          = "users"
 		authorizedKeys = "authorizedKeys"
@@ -31,28 +31,26 @@ func (l *sshListener) parseMetadata(md md.Metadata) (err error) {
 		backlog        = "backlog"
 	)
 
-	if v, _ := md.Get(users).([]interface{}); len(v) > 0 {
+	if auths := mdata.GetStrings(md, users); len(auths) > 0 {
 		authenticator := auth.NewLocalAuthenticator(nil)
-		for _, auth := range v {
+		for _, auth := range auths {
-			if s, _ := auth.(string); s != "" {
+			ss := strings.SplitN(auth, ":", 2)
-				ss := strings.SplitN(s, ":", 2)
+			if len(ss) == 1 {
-				if len(ss) == 1 {
+				authenticator.Add(ss[0], "")
-					authenticator.Add(ss[0], "")
+			} else {
-				} else {
+				authenticator.Add(ss[0], ss[1])
-					authenticator.Add(ss[0], ss[1])
-				}
 			}
 		}
 		l.md.authenticator = authenticator
 	}
 
-	if key := md.GetString(privateKeyFile); key != "" {
+	if key := mdata.GetString(md, privateKeyFile); key != "" {
 		data, err := ioutil.ReadFile(key)
 		if err != nil {
 			return err
 		}
 
-		pp := md.GetString(passphrase)
+		pp := mdata.GetString(md, passphrase)
 		if pp == "" {
 			l.md.signer, err = ssh.ParsePrivateKey(data)
 		} else {
@@ -70,7 +68,7 @@ func (l *sshListener) parseMetadata(md md.Metadata) (err error) {
 		l.md.signer = signer
 	}
 
-	if name := md.GetString(authorizedKeys); name != "" {
+	if name := mdata.GetString(md, authorizedKeys); name != "" {
 		m, err := ssh_util.ParseAuthorizedKeysFile(name)
 		if err != nil {
 			return err
@@ -78,7 +76,7 @@ func (l *sshListener) parseMetadata(md md.Metadata) (err error) {
 		l.md.authorizedKeys = m
 	}
 
-	l.md.backlog = md.GetInt(backlog)
+	l.md.backlog = mdata.GetInt(md, backlog)
 	if l.md.backlog <= 0 {
 		l.md.backlog = defaultBacklog
 	}

pkg/listener/tap/listener.go

@@ -0,0 +1,96 @@
+package tap
+
+import (
+	"net"
+
+	tap_util "github.com/go-gost/gost/pkg/internal/util/tap"
+	"github.com/go-gost/gost/pkg/listener"
+	"github.com/go-gost/gost/pkg/logger"
+	md "github.com/go-gost/gost/pkg/metadata"
+	"github.com/go-gost/gost/pkg/registry"
+)
+
+func init() {
+	registry.RegisterListener("tap", NewListener)
+}
+
+type tapListener struct {
+	saddr  string
+	addr   net.Addr
+	cqueue chan net.Conn
+	closed chan struct{}
+	logger logger.Logger
+	md     metadata
+}
+
+func NewListener(opts ...listener.Option) listener.Listener {
+	options := &listener.Options{}
+	for _, opt := range opts {
+		opt(options)
+	}
+	return &tapListener{
+		saddr:  options.Addr,
+		logger: options.Logger,
+	}
+}
+
+func (l *tapListener) Init(md md.Metadata) (err error) {
+	if err = l.parseMetadata(md); err != nil {
+		return
+	}
+
+	l.addr, err = net.ResolveUDPAddr("udp", l.saddr)
+	if err != nil {
+		return
+	}
+
+	ifce, ip, err := l.createTap()
+	if err != nil {
+		if ifce != nil {
+			ifce.Close()
+		}
+		return
+	}
+
+	itf, err := net.InterfaceByName(ifce.Name())
+	if err != nil {
+		return
+	}
+
+	addrs, _ := itf.Addrs()
+	l.logger.Infof("name: %s, mac: %s, mtu: %d, addrs: %s",
+		itf.Name, itf.HardwareAddr, itf.MTU, addrs)
+
+	l.cqueue = make(chan net.Conn, 1)
+	l.closed = make(chan struct{})
+
+	conn := tap_util.NewConn(l.md.config, ifce, l.addr, &net.IPAddr{IP: ip})
+
+	l.cqueue <- conn
+
+	return
+}
+
+func (l *tapListener) Accept() (net.Conn, error) {
+	select {
+	case conn := <-l.cqueue:
+		return conn, nil
+	case <-l.closed:
+	}
+
+	return nil, listener.ErrClosed
+}
+
+func (l *tapListener) Addr() net.Addr {
+	return l.addr
+}
+
+func (l *tapListener) Close() error {
+	select {
+	case <-l.closed:
+		return net.ErrClosed
+	default:
+		close(l.closed)
+	}
+	return nil
+}

pkg/listener/tap/metadata.go

@@ -0,0 +1,44 @@
+package tap
+
+import (
+	tap_util "github.com/go-gost/gost/pkg/internal/util/tap"
+	mdata "github.com/go-gost/gost/pkg/metadata"
+)
+
+const (
+	DefaultMTU = 1350
+)
+
+type metadata struct {
+	config *tap_util.Config
+}
+
+func (l *tapListener) parseMetadata(md mdata.Metadata) (err error) {
+	const (
+		name    = "name"
+		netKey  = "net"
+		mtu     = "mtu"
+		routes  = "routes"
+		gateway = "gw"
+	)
+
+	config := &tap_util.Config{
+		Name:    mdata.GetString(md, name),
+		Net:     mdata.GetString(md, netKey),
+		MTU:     mdata.GetInt(md, mtu),
+		Gateway: mdata.GetString(md, gateway),
+	}
+	if config.MTU <= 0 {
+		config.MTU = DefaultMTU
+	}
+
+	for _, s := range mdata.GetStrings(md, routes) {
+		if s != "" {
+			config.Routes = append(config.Routes, s)
+		}
+	}
+
+	l.md.config = config
+
+	return
+}

pkg/listener/tap/tap_darwin.go

@@ -0,0 +1,13 @@
+package tap
+
+import (
+	"errors"
+	"net"
+
+	"github.com/songgao/water"
+)
+
+func (l *tapListener) createTap() (ifce *water.Interface, ip net.IP, err error) {
+	err = errors.New("tap is not supported on darwin")
+	return
+}

pkg/listener/tap/tap_linux.go

@@ -0,0 +1,69 @@
+package tap
+
+import (
+	"net"
+
+	"github.com/docker/libcontainer/netlink"
+	"github.com/milosgajdos/tenus"
+	"github.com/songgao/water"
+)
+
+func (l *tapListener) createTap() (ifce *water.Interface, ip net.IP, err error) {
+	var ipNet *net.IPNet
+	if l.md.config.Net != "" {
+		ip, ipNet, err = net.ParseCIDR(l.md.config.Net)
+		if err != nil {
+			return
+		}
+	}
+
+	ifce, err = water.New(water.Config{
+		DeviceType: water.TAP,
+		PlatformSpecificParams: water.PlatformSpecificParams{
+			Name: l.md.config.Name,
+		},
+	})
+	if err != nil {
+		return
+	}
+
+	link, err := tenus.NewLinkFrom(ifce.Name())
+	if err != nil {
+		return
+	}
+
+	l.logger.Debugf("ip link set dev %s mtu %d", ifce.Name(), l.md.config.MTU)
+
+	if err = link.SetLinkMTU(l.md.config.MTU); err != nil {
+		return
+	}
+
+	if l.md.config.Net != "" {
+		l.logger.Debugf("ip address add %s dev %s", l.md.config.Net, ifce.Name())
+
+		if err = link.SetLinkIp(ip, ipNet); err != nil {
+			return
+		}
+	}
+
+	l.logger.Debugf("ip link set dev %s up", ifce.Name())
+	if err = link.SetLinkUp(); err != nil {
+		return
+	}
+
+	if err = l.addRoutes(ifce.Name(), l.md.config.Gateway, l.md.config.Routes...); err != nil {
+		return
+	}
+
+	return
+}
+
+func (l *tapListener) addRoutes(ifName string, gw string, routes ...string) error {
+	for _, route := range routes {
+		l.logger.Debugf("ip route add %s via %s dev %s", route, gw, ifName)
+		if err := netlink.AddRoute(route, "", gw, ifName); err != nil {
+			return err
+		}
+	}
+	return nil
+}

pkg/listener/tap/tap_unix.go

@@ -0,0 +1,61 @@
+//go:build !linux && !windows && !darwin
+
+package tap
+
+import (
+	"fmt"
+	"net"
+	"os/exec"
+	"strings"
+
+	"github.com/songgao/water"
+)
+
+func (l *tapListener) createTap() (ifce *water.Interface, ip net.IP, err error) {
+	ip, _, _ = net.ParseCIDR(l.md.config.Net)
+
+	ifce, err = water.New(water.Config{
+		DeviceType: water.TAP,
+	})
+	if err != nil {
+		return
+	}
+
+	var cmd string
+	if l.md.config.Net != "" {
+		cmd = fmt.Sprintf("ifconfig %s inet %s mtu %d up", ifce.Name(), l.md.config.Net, l.md.config.MTU)
+	} else {
+		cmd = fmt.Sprintf("ifconfig %s mtu %d up", ifce.Name(), l.md.config.MTU)
+	}
+	l.logger.Debug(cmd)
+
+	args := strings.Split(cmd, " ")
+	if er := exec.Command(args[0], args[1:]...).Run(); er != nil {
+		err = fmt.Errorf("%s: %v", cmd, er)
+		return
+	}
+
+	if err = l.addRoutes(ifce.Name(), l.md.config.Gateway, l.md.config.Routes...); err != nil {
+		return
+	}
+
+	return
+}
+
+func (l *tapListener) addRoutes(ifName string, gw string, routes ...string) error {
+	for _, route := range routes {
+		if route == "" {
+			continue
+		}
+		cmd := fmt.Sprintf("route add -net %s dev %s", route, ifName)
+		if gw != "" {
+			cmd += " gw " + gw
+		}
+		l.logger.Debug(cmd)
+		args := strings.Split(cmd, " ")
+		if er := exec.Command(args[0], args[1:]...).Run(); er != nil {
+			return fmt.Errorf("%s: %v", cmd, er)
+		}
+	}
+	return nil
+}

pkg/listener/tap/tap_windows.go

@@ -0,0 +1,75 @@
+package tap
+
+import (
+	"fmt"
+	"net"
+	"os/exec"
+	"strings"
+
+	"github.com/songgao/water"
+)
+
+func (l *tapListener) createTap() (ifce *water.Interface, ip net.IP, err error) {
+	ip, ipNet, _ := net.ParseCIDR(l.md.config.Net)
+
+	ifce, err = water.New(water.Config{
+		DeviceType: water.TAP,
+		PlatformSpecificParams: water.PlatformSpecificParams{
+			ComponentID:   "tap0901",
+			InterfaceName: l.md.config.Name,
+			Network:       l.md.config.Net,
+		},
+	})
+	if err != nil {
+		return
+	}
+
+	if ip != nil && ipNet != nil {
+		cmd := fmt.Sprintf("netsh interface ip set address name=%s "+
+			"source=static addr=%s mask=%s gateway=none",
+			ifce.Name(), ip.String(), ipMask(ipNet.Mask))
+		l.logger.Debug(cmd)
+
+		args := strings.Split(cmd, " ")
+		if er := exec.Command(args[0], args[1:]...).Run(); er != nil {
+			err = fmt.Errorf("%s: %v", cmd, er)
+			return
+		}
+	}
+
+	if err = l.addRoutes(ifce.Name(), l.md.config.Gateway, l.md.config.Routes...); err != nil {
+		return
+	}
+
+	return
+}
+
+func (l *tapListener) addRoutes(ifName string, gw string, routes ...string) error {
+	for _, route := range routes {
+		l.deleteRoute(ifName, route)
+
+		cmd := fmt.Sprintf("netsh interface ip add route prefix=%s interface=%s store=active",
+			route, ifName)
+		if gw != "" {
+			cmd += " nexthop=" + gw
+		}
+		l.logger.Debug(cmd)
+		args := strings.Split(cmd, " ")
+		if er := exec.Command(args[0], args[1:]...).Run(); er != nil {
+			return fmt.Errorf("%s: %v", cmd, er)
+		}
+	}
+	return nil
+}
+
+func (l *tapListener) deleteRoute(ifName string, route string) error {
+	cmd := fmt.Sprintf("netsh interface ip delete route prefix=%s interface=%s store=active",
+		route, ifName)
+	l.logger.Debug(cmd)
+	args := strings.Split(cmd, " ")
+	return exec.Command(args[0], args[1:]...).Run()
+}
+
+func ipMask(mask net.IPMask) string {
+	return fmt.Sprintf("%d.%d.%d.%d", mask[0], mask[1], mask[2], mask[3])
+}

pkg/listener/tls/metadata.go

@@ -4,14 +4,14 @@ import (
 	"crypto/tls"
 
 	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 type metadata struct {
 	tlsConfig *tls.Config
 }
 
-func (l *tlsListener) parseMetadata(md md.Metadata) (err error) {
+func (l *tlsListener) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		certFile = "certFile"
 		keyFile  = "keyFile"
@@ -19,9 +19,9 @@ func (l *tlsListener) parseMetadata(md md.Metadata) (err error) {
 	)
 
 	l.md.tlsConfig, err = tls_util.LoadServerConfig(
-		md.GetString(certFile),
+		mdata.GetString(md, certFile),
-		md.GetString(keyFile),
+		mdata.GetString(md, keyFile),
-		md.GetString(caFile),
+		mdata.GetString(md, caFile),
 	)
 	if err != nil {
 		return

pkg/listener/tls/mux/metadata.go

@@ -5,7 +5,7 @@ import (
 	"time"
 
 	tls_util "github.com/go-gost/gost/pkg/common/util/tls"
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 const (
@@ -25,7 +25,7 @@ type metadata struct {
 	backlog int
 }
 
-func (l *mtlsListener) parseMetadata(md md.Metadata) (err error) {
+func (l *mtlsListener) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		certFile = "certFile"
 		keyFile  = "keyFile"
@@ -42,25 +42,25 @@ func (l *mtlsListener) parseMetadata(md md.Metadata) (err error) {
 	)
 
 	l.md.tlsConfig, err = tls_util.LoadServerConfig(
-		md.GetString(certFile),
+		mdata.GetString(md, certFile),
-		md.GetString(keyFile),
+		mdata.GetString(md, keyFile),
-		md.GetString(caFile),
+		mdata.GetString(md, caFile),
 	)
 	if err != nil {
 		return
 	}
 
-	l.md.backlog = md.GetInt(backlog)
+	l.md.backlog = mdata.GetInt(md, backlog)
 	if l.md.backlog <= 0 {
 		l.md.backlog = defaultBacklog
 	}
 
-	l.md.muxKeepAliveDisabled = md.GetBool(muxKeepAliveDisabled)
+	l.md.muxKeepAliveDisabled = mdata.GetBool(md, muxKeepAliveDisabled)
-	l.md.muxKeepAliveInterval = md.GetDuration(muxKeepAliveInterval)
+	l.md.muxKeepAliveInterval = mdata.GetDuration(md, muxKeepAliveInterval)
-	l.md.muxKeepAliveTimeout = md.GetDuration(muxKeepAliveTimeout)
+	l.md.muxKeepAliveTimeout = mdata.GetDuration(md, muxKeepAliveTimeout)
-	l.md.muxMaxFrameSize = md.GetInt(muxMaxFrameSize)
+	l.md.muxMaxFrameSize = mdata.GetInt(md, muxMaxFrameSize)
-	l.md.muxMaxReceiveBuffer = md.GetInt(muxMaxReceiveBuffer)
+	l.md.muxMaxReceiveBuffer = mdata.GetInt(md, muxMaxReceiveBuffer)
-	l.md.muxMaxStreamBuffer = md.GetInt(muxMaxStreamBuffer)
+	l.md.muxMaxStreamBuffer = mdata.GetInt(md, muxMaxStreamBuffer)
 
 	return
 }

pkg/listener/tun/conn.go

@@ -1,46 +0,0 @@
-package tun
-
-import (
-	"errors"
-	"net"
-	"time"
-
-	"github.com/songgao/water"
-)
-
-type tunConn struct {
-	ifce *water.Interface
-	addr net.Addr
-}
-
-func (c *tunConn) Read(b []byte) (n int, err error) {
-	return c.ifce.Read(b)
-}
-
-func (c *tunConn) Write(b []byte) (n int, err error) {
-	return c.ifce.Write(b)
-}
-
-func (c *tunConn) Close() (err error) {
-	return c.ifce.Close()
-}
-
-func (c *tunConn) LocalAddr() net.Addr {
-	return c.addr
-}
-
-func (c *tunConn) RemoteAddr() net.Addr {
-	return &net.IPAddr{}
-}
-
-func (c *tunConn) SetDeadline(t time.Time) error {
-	return &net.OpError{Op: "set", Net: "tuntap", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
-}
-
-func (c *tunConn) SetReadDeadline(t time.Time) error {
-	return &net.OpError{Op: "set", Net: "tuntap", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
-}
-
-func (c *tunConn) SetWriteDeadline(t time.Time) error {
-	return &net.OpError{Op: "set", Net: "tuntap", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
-}

pkg/listener/tun/listener.go

@@ -3,18 +3,13 @@ package tun
 import (
 	"net"
 
+	tun_util "github.com/go-gost/gost/pkg/internal/util/tun"
 	"github.com/go-gost/gost/pkg/listener"
 	"github.com/go-gost/gost/pkg/logger"
 	md "github.com/go-gost/gost/pkg/metadata"
 	"github.com/go-gost/gost/pkg/registry"
 )
 
-// ipRoute is an IP routing entry
-type ipRoute struct {
-	Dest    net.IPNet
-	Gateway net.IP
-}
-
 func init() {
 	registry.RegisterListener("tun", NewListener)
 }
@@ -44,19 +39,33 @@ func (l *tunListener) Init(md md.Metadata) (err error) {
 		return
 	}
 
-	conn, ifce, err := l.createTun()
+	l.addr, err = net.ResolveUDPAddr("udp", l.saddr)
 	if err != nil {
 		return
 	}
 
-	addrs, _ := ifce.Addrs()
+	ifce, ip, err := l.createTun()
-	l.logger.Infof("name: %s, net: %s, mtu: %d, addrs: %s",
+	if err != nil {
-		ifce.Name, conn.LocalAddr(), ifce.MTU, addrs)
+		if ifce != nil {
+			ifce.Close()
+		}
+		return
+	}
+
+	itf, err := net.InterfaceByName(ifce.Name())
+	if err != nil {
+		return
+	}
+
+	addrs, _ := itf.Addrs()
+	l.logger.Infof("name: %s, net: %s, mtu: %d, addrs: %s",
+		itf.Name, ip, itf.MTU, addrs)
 
-	l.addr = conn.LocalAddr()
 	l.cqueue = make(chan net.Conn, 1)
 	l.closed = make(chan struct{})
 
+	conn := tun_util.NewConn(l.md.config, ifce, l.addr, &net.IPAddr{IP: ip})
+
 	l.cqueue <- conn
 
 	return

pkg/listener/tun/metadata.go

@@ -4,7 +4,8 @@ import (
 	"net"
 	"strings"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	tun_util "github.com/go-gost/gost/pkg/internal/util/tun"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 const (
@@ -12,18 +13,10 @@ const (
 )
 
 type metadata struct {
-	name string
+	config *tun_util.Config
-	net  string
-	// peer addr of point-to-point on MacOS
-	peer   string
-	mtu    int
-	routes []ipRoute
-	// default gateway
-	gateway string
-	tcp     bool
 }
 
-func (l *tunListener) parseMetadata(md md.Metadata) (err error) {
+func (l *tunListener) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		name    = "name"
 		netKey  = "net"
@@ -31,40 +24,40 @@ func (l *tunListener) parseMetadata(md md.Metadata) (err error) {
 		mtu     = "mtu"
 		routes  = "routes"
 		gateway = "gw"
-		tcp     = "tcp"
 	)
 
-	l.md.name = md.GetString(name)
+	config := &tun_util.Config{
-	l.md.net = md.GetString(netKey)
+		Name:    mdata.GetString(md, name),
-	l.md.peer = md.GetString(peer)
+		Net:     mdata.GetString(md, netKey),
-	l.md.mtu = md.GetInt(mtu)
+		Peer:    mdata.GetString(md, peer),
-
+		MTU:     mdata.GetInt(md, mtu),
-	if l.md.mtu <= 0 {
+		Gateway: mdata.GetString(md, gateway),
-		l.md.mtu = DefaultMTU
+	}
+	if config.MTU <= 0 {
+		config.MTU = DefaultMTU
 	}
 
-	l.md.gateway = md.GetString(gateway)
+	gw := net.ParseIP(config.Gateway)
-	l.md.tcp = md.GetBool(tcp)
 
-	gw := net.ParseIP(l.md.gateway)
+	for _, s := range mdata.GetStrings(md, routes) {
-
-	for _, s := range md.GetStrings(routes) {
 		ss := strings.SplitN(s, " ", 2)
 		if len(ss) == 2 {
-			var route ipRoute
+			var route tun_util.Route
 			_, ipNet, _ := net.ParseCIDR(strings.TrimSpace(ss[0]))
 			if ipNet == nil {
 				continue
 			}
-			route.Dest = *ipNet
+			route.Net = *ipNet
 			route.Gateway = net.ParseIP(ss[1])
 			if route.Gateway == nil {
 				route.Gateway = gw
 			}
 
-			l.md.routes = append(l.md.routes, route)
+			config.Routes = append(config.Routes, route)
 		}
 	}
 
+	l.md.config = config
+
 	return
 }

pkg/listener/tun/tun_darwin.go

@@ -6,29 +6,30 @@ import (
 	"os/exec"
 	"strings"
 
+	tun_util "github.com/go-gost/gost/pkg/internal/util/tun"
 	"github.com/songgao/water"
 )
 
-func (l *tunListener) createTun() (conn net.Conn, itf *net.Interface, err error) {
+func (l *tunListener) createTun() (ifce *water.Interface, ip net.IP, err error) {
-	ip, _, err := net.ParseCIDR(l.md.net)
+	ip, _, err = net.ParseCIDR(l.md.config.Net)
 	if err != nil {
 		return
 	}
 
-	ifce, err := water.New(water.Config{
+	ifce, err = water.New(water.Config{
 		DeviceType: water.TUN,
 	})
 	if err != nil {
 		return
 	}
 
-	peer := l.md.peer
+	peer := l.md.config.Peer
 	if peer == "" {
 		peer = ip.String()
 	}
 
 	cmd := fmt.Sprintf("ifconfig %s inet %s %s mtu %d up",
-		ifce.Name(), l.md.net, l.md.peer, l.md.mtu)
+		ifce.Name(), l.md.config.Net, l.md.config.Peer, l.md.config.MTU)
 	l.logger.Debug(cmd)
 
 	args := strings.Split(cmd, " ")
@@ -36,25 +37,16 @@ func (l *tunListener) createTun() (conn net.Conn, itf *net.Interface, err error)
 		return
 	}
 
-	if err = l.addRoutes(ifce.Name(), l.md.routes...); err != nil {
+	if err = l.addRoutes(ifce.Name(), l.md.config.Routes...); err != nil {
 		return
 	}
 
-	itf, err = net.InterfaceByName(ifce.Name())
-	if err != nil {
-		return
-	}
-
-	conn = &tunConn{
-		ifce: ifce,
-		addr: &net.IPAddr{IP: ip},
-	}
 	return
 }
 
-func (l *tunListener) addRoutes(ifName string, routes ...ipRoute) error {
+func (l *tunListener) addRoutes(ifName string, routes ...tun_util.Route) error {
 	for _, route := range routes {
-		cmd := fmt.Sprintf("route add -net %s -interface %s", route.Dest.String(), ifName)
+		cmd := fmt.Sprintf("route add -net %s -interface %s", route.Net.String(), ifName)
 		l.logger.Debug(cmd)
 		args := strings.Split(cmd, " ")
 		if err := exec.Command(args[0], args[1:]...).Run(); err != nil {

pkg/listener/tun/tun_linux.go

@@ -6,20 +6,21 @@ import (
 	"syscall"
 
 	"github.com/docker/libcontainer/netlink"
+	tun_util "github.com/go-gost/gost/pkg/internal/util/tun"
 	"github.com/milosgajdos/tenus"
 	"github.com/songgao/water"
 )
 
-func (l *tunListener) createTun() (conn net.Conn, itf *net.Interface, err error) {
+func (l *tunListener) createTun() (ifce *water.Interface, ip net.IP, err error) {
-	ip, ipNet, err := net.ParseCIDR(l.md.net)
+	ip, ipNet, err := net.ParseCIDR(l.md.config.Net)
 	if err != nil {
 		return
 	}
 
-	ifce, err := water.New(water.Config{
+	ifce, err = water.New(water.Config{
 		DeviceType: water.TUN,
 		PlatformSpecificParams: water.PlatformSpecificParams{
-			Name: l.md.name,
+			Name: l.md.config.Name,
 		},
 	})
 	if err != nil {
@@ -31,13 +32,13 @@ func (l *tunListener) createTun() (conn net.Conn, itf *net.Interface, err error)
 		return
 	}
 
-	l.logger.Debugf("ip link set dev %s mtu %d", ifce.Name(), l.md.mtu)
+	l.logger.Debugf("ip link set dev %s mtu %d", ifce.Name(), l.md.config.MTU)
 
-	if err = link.SetLinkMTU(l.md.mtu); err != nil {
+	if err = link.SetLinkMTU(l.md.config.MTU); err != nil {
 		return
 	}
 
-	l.logger.Debugf("ip address add %s dev %s", l.md.net, ifce.Name())
+	l.logger.Debugf("ip address add %s dev %s", l.md.config.Net, ifce.Name())
 
 	if err = link.SetLinkIp(ip, ipNet); err != nil {
 		return
@@ -48,26 +49,17 @@ func (l *tunListener) createTun() (conn net.Conn, itf *net.Interface, err error)
 		return
 	}
 
-	if err = l.addRoutes(ifce.Name(), l.md.routes...); err != nil {
+	if err = l.addRoutes(ifce.Name(), l.md.config.Routes...); err != nil {
 		return
 	}
 
-	itf, err = net.InterfaceByName(ifce.Name())
-	if err != nil {
-		return
-	}
-
-	conn = &tunConn{
-		ifce: ifce,
-		addr: &net.IPAddr{IP: ip},
-	}
 	return
 }
 
-func (l *tunListener) addRoutes(ifName string, routes ...ipRoute) error {
+func (l *tunListener) addRoutes(ifName string, routes ...tun_util.Route) error {
 	for _, route := range routes {
-		l.logger.Debugf("ip route add %s dev %s", route.Dest.String(), ifName)
+		l.logger.Debugf("ip route add %s dev %s", route.Net.String(), ifName)
-		if err := netlink.AddRoute(route.Dest.String(), "", "", ifName); err != nil && !errors.Is(err, syscall.EEXIST) {
+		if err := netlink.AddRoute(route.Net.String(), "", "", ifName); err != nil && !errors.Is(err, syscall.EEXIST) {
 			return err
 		}
 	}

pkg/listener/tun/tun_unix.go

@@ -8,16 +8,17 @@ import (
 	"os/exec"
 	"strings"
 
+	tun_util "github.com/go-gost/gost/pkg/internal/util/tun"
 	"github.com/songgao/water"
 )
 
-func (l *tunListener) createTun() (conn net.Conn, itf *net.Interface, err error) {
+func (l *tunListener) createTun() (ifce *water.Interface, ip net.IP, err error) {
-	ip, _, err := net.ParseCIDR(l.md.net)
+	ip, _, err = net.ParseCIDR(l.md.config.Net)
 	if err != nil {
 		return
 	}
 
-	ifce, err := water.New(water.Config{
+	ifce, err = water.New(water.Config{
 		DeviceType: water.TUN,
 	})
 	if err != nil {
@@ -25,33 +26,25 @@ func (l *tunListener) createTun() (conn net.Conn, itf *net.Interface, err error)
 	}
 
 	cmd := fmt.Sprintf("ifconfig %s inet %s mtu %d up",
-		ifce.Name(), l.md.net, l.md.mtu)
+		ifce.Name(), l.md.config.Net, l.md.config.MTU)
 	l.logger.Debug(cmd)
+
 	args := strings.Split(cmd, " ")
 	if er := exec.Command(args[0], args[1:]...).Run(); er != nil {
 		err = fmt.Errorf("%s: %v", cmd, er)
 		return
 	}
 
-	if err = l.addRoutes(ifce.Name(), l.md.routes...); err != nil {
+	if err = l.addRoutes(ifce.Name(), l.md.config.Routes...); err != nil {
 		return
 	}
 
-	itf, err = net.InterfaceByName(ifce.Name())
-	if err != nil {
-		return
-	}
-
-	conn = &tunConn{
-		ifce: ifce,
-		addr: &net.IPAddr{IP: ip},
-	}
 	return
 }
 
-func (l *tunListener) addRoutes(ifName string, routes ...ipRoute) error {
+func (l *tunListener) addRoutes(ifName string, routes ...tun_util.Route) error {
 	for _, route := range routes {
-		cmd := fmt.Sprintf("route add -net %s -interface %s", route.Dest.String(), ifName)
+		cmd := fmt.Sprintf("route add -net %s -interface %s", route.Net.String(), ifName)
 		l.logger.Debug(cmd)
 		args := strings.Split(cmd, " ")
 		if er := exec.Command(args[0], args[1:]...).Run(); er != nil {

pkg/listener/tun/tun_windows.go

@@ -6,21 +6,22 @@ import (
 	"os/exec"
 	"strings"
 
+	tun_util "github.com/go-gost/gost/pkg/internal/util/tun"
 	"github.com/songgao/water"
 )
 
-func (l *tunListener) createTun() (conn net.Conn, itf *net.Interface, err error) {
+func (l *tunListener) createTun() (ifce *water.Interface, ip net.IP, err error) {
-	ip, ipNet, err := net.ParseCIDR(l.md.net)
+	ip, ipNet, err := net.ParseCIDR(l.md.config.Net)
 	if err != nil {
 		return
 	}
 
-	ifce, err := water.New(water.Config{
+	ifce, err = water.New(water.Config{
 		DeviceType: water.TUN,
 		PlatformSpecificParams: water.PlatformSpecificParams{
 			ComponentID:   "tap0901",
-			InterfaceName: l.md.name,
+			InterfaceName: l.md.config.Name,
-			Network:       l.md.net,
+			Network:       l.md.config.Net,
 		},
 	})
 	if err != nil {
@@ -38,28 +39,19 @@ func (l *tunListener) createTun() (conn net.Conn, itf *net.Interface, err error)
 		return
 	}
 
-	if err = l.addRoutes(ifce.Name(), l.md.gateway, l.md.routes...); err != nil {
+	if err = l.addRoutes(ifce.Name(), l.md.config.Gateway, l.md.config.Routes...); err != nil {
 		return
 	}
 
-	itf, err = net.InterfaceByName(ifce.Name())
-	if err != nil {
-		return
-	}
-
-	conn = &tunConn{
-		ifce: ifce,
-		addr: &net.IPAddr{IP: ip},
-	}
 	return
 }
 
-func (l *tunListener) addRoutes(ifName string, gw string, routes ...ipRoute) error {
+func (l *tunListener) addRoutes(ifName string, gw string, routes ...tun_util.Route) error {
 	for _, route := range routes {
-		l.deleteRoute(ifName, route.Dest.String())
+		l.deleteRoute(ifName, route.Net.String())
 
 		cmd := fmt.Sprintf("netsh interface ip add route prefix=%s interface=%s store=active",
-			route.Dest.String(), ifName)
+			route.Net.String(), ifName)
 		if gw != "" {
 			cmd += " nexthop=" + gw
 		}

pkg/listener/udp/metadata.go

@@ -3,7 +3,7 @@ package udp
 import (
 	"time"
 
-	md "github.com/go-gost/gost/pkg/metadata"
+	mdata "github.com/go-gost/gost/pkg/metadata"
 )
 
 const (
@@ -21,7 +21,7 @@ type metadata struct {
 	backlog        int
 }
 
-func (l *udpListener) parseMetadata(md md.Metadata) (err error) {
+func (l *udpListener) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		ttl            = "ttl"
 		readBufferSize = "readBufferSize"
@@ -29,21 +29,21 @@ func (l *udpListener) parseMetadata(md md.Metadata) (err error) {
 		backlog        = "backlog"
 	)
 
-	l.md.ttl = md.GetDuration(ttl)
+	l.md.ttl = mdata.GetDuration(md, ttl)
 	if l.md.ttl <= 0 {
 		l.md.ttl = defaultTTL
 	}
-	l.md.readBufferSize = md.GetInt(readBufferSize)
+	l.md.readBufferSize = mdata.GetInt(md, readBufferSize)
 	if l.md.readBufferSize <= 0 {
 		l.md.readBufferSize = defaultReadBufferSize
 	}
 
-	l.md.readQueueSize = md.GetInt(readQueueSize)
+	l.md.readQueueSize = mdata.GetInt(md, readQueueSize)
 	if l.md.readQueueSize <= 0 {
 		l.md.readQueueSize = defaultReadQueueSize
 	}
 
-	l.md.backlog = md.GetInt(backlog)
+	l.md.backlog = mdata.GetInt(md, backlog)
 	if l.md.backlog <= 0 {
 		l.md.backlog = defaultBacklog
 	}

pkg/listener/ws/metadata.go

@@ -47,29 +47,29 @@ func (l *wsListener) parseMetadata(md mdata.Metadata) (err error) {
 	)
 
 	l.md.tlsConfig, err = tls_util.LoadServerConfig(
-		md.GetString(certFile),
+		mdata.GetString(md, certFile),
-		md.GetString(keyFile),
+		mdata.GetString(md, keyFile),
-		md.GetString(caFile),
+		mdata.GetString(md, caFile),
 	)
 	if err != nil {
 		return
 	}
 
-	l.md.path = md.GetString(path)
+	l.md.path = mdata.GetString(md, path)
 	if l.md.path == "" {
 		l.md.path = defaultPath
 	}
 
-	l.md.backlog = md.GetInt(backlog)
+	l.md.backlog = mdata.GetInt(md, backlog)
 	if l.md.backlog <= 0 {
 		l.md.backlog = defaultBacklog
 	}
 
-	l.md.handshakeTimeout = md.GetDuration(handshakeTimeout)
+	l.md.handshakeTimeout = mdata.GetDuration(md, handshakeTimeout)
-	l.md.readHeaderTimeout = md.GetDuration(readHeaderTimeout)
+	l.md.readHeaderTimeout = mdata.GetDuration(md, readHeaderTimeout)
-	l.md.readBufferSize = md.GetInt(readBufferSize)
+	l.md.readBufferSize = mdata.GetInt(md, readBufferSize)
-	l.md.writeBufferSize = md.GetInt(writeBufferSize)
+	l.md.writeBufferSize = mdata.GetInt(md, writeBufferSize)
-	l.md.enableCompression = md.GetBool(enableCompression)
+	l.md.enableCompression = mdata.GetBool(md, enableCompression)
 
 	if mm := mdata.GetStringMapString(md, header); len(mm) > 0 {
 		hd := http.Header{}

pkg/listener/ws/mux/metadata.go

@@ -59,36 +59,36 @@ func (l *mwsListener) parseMetadata(md mdata.Metadata) (err error) {
 	)
 
 	l.md.tlsConfig, err = tls_util.LoadServerConfig(
-		md.GetString(certFile),
+		mdata.GetString(md, certFile),
-		md.GetString(keyFile),
+		mdata.GetString(md, keyFile),
-		md.GetString(caFile),
+		mdata.GetString(md, caFile),
 	)
 	if err != nil {
 		return
 	}
 
-	l.md.path = md.GetString(path)
+	l.md.path = mdata.GetString(md, path)
 	if l.md.path == "" {
 		l.md.path = defaultPath
 	}
 
-	l.md.backlog = md.GetInt(backlog)
+	l.md.backlog = mdata.GetInt(md, backlog)
 	if l.md.backlog <= 0 {
 		l.md.backlog = defaultBacklog
 	}
 
-	l.md.handshakeTimeout = md.GetDuration(handshakeTimeout)
+	l.md.handshakeTimeout = mdata.GetDuration(md, handshakeTimeout)
-	l.md.readHeaderTimeout = md.GetDuration(readHeaderTimeout)
+	l.md.readHeaderTimeout = mdata.GetDuration(md, readHeaderTimeout)
-	l.md.readBufferSize = md.GetInt(readBufferSize)
+	l.md.readBufferSize = mdata.GetInt(md, readBufferSize)
-	l.md.writeBufferSize = md.GetInt(writeBufferSize)
+	l.md.writeBufferSize = mdata.GetInt(md, writeBufferSize)
-	l.md.enableCompression = md.GetBool(enableCompression)
+	l.md.enableCompression = mdata.GetBool(md, enableCompression)
 
-	l.md.muxKeepAliveDisabled = md.GetBool(muxKeepAliveDisabled)
+	l.md.muxKeepAliveDisabled = mdata.GetBool(md, muxKeepAliveDisabled)
-	l.md.muxKeepAliveInterval = md.GetDuration(muxKeepAliveInterval)
+	l.md.muxKeepAliveInterval = mdata.GetDuration(md, muxKeepAliveInterval)
-	l.md.muxKeepAliveTimeout = md.GetDuration(muxKeepAliveTimeout)
+	l.md.muxKeepAliveTimeout = mdata.GetDuration(md, muxKeepAliveTimeout)
-	l.md.muxMaxFrameSize = md.GetInt(muxMaxFrameSize)
+	l.md.muxMaxFrameSize = mdata.GetInt(md, muxMaxFrameSize)
-	l.md.muxMaxReceiveBuffer = md.GetInt(muxMaxReceiveBuffer)
+	l.md.muxMaxReceiveBuffer = mdata.GetInt(md, muxMaxReceiveBuffer)
-	l.md.muxMaxStreamBuffer = md.GetInt(muxMaxStreamBuffer)
+	l.md.muxMaxStreamBuffer = mdata.GetInt(md, muxMaxStreamBuffer)
 
 	if mm := mdata.GetStringMapString(md, header); len(mm) > 0 {
 		hd := http.Header{}

pkg/metadata/metadata.go

@@ -10,12 +10,6 @@ type Metadata interface {
 	IsExists(key string) bool
 	Set(key string, value interface{})
 	Get(key string) interface{}
-	GetBool(key string) bool
-	GetInt(key string) int
-	GetFloat(key string) float64
-	GetDuration(key string) time.Duration
-	GetString(key string) string
-	GetStrings(key string) []string
 }
 
 type MapMetadata map[string]interface{}
@@ -36,11 +30,11 @@ func (m MapMetadata) Get(key string) interface{} {
 	return nil
 }
 
-func (m MapMetadata) GetBool(key string) (v bool) {
+func GetBool(md Metadata, key string) (v bool) {
-	if m == nil || !m.IsExists(key) {
+	if md == nil || !md.IsExists(key) {
 		return
 	}
-	switch vv := m[key].(type) {
+	switch vv := md.Get(key).(type) {
 	case bool:
 		return vv
 	case int:
@@ -52,8 +46,12 @@ func (m MapMetadata) GetBool(key string) (v bool) {
 	return
 }
 
-func (m MapMetadata) GetInt(key string) (v int) {
+func GetInt(md Metadata, key string) (v int) {
-	switch vv := m[key].(type) {
+	if md == nil {
+		return
+	}
+
+	switch vv := md.Get(key).(type) {
 	case bool:
 		if vv {
 			v = 1
@@ -67,8 +65,12 @@ func (m MapMetadata) GetInt(key string) (v int) {
 	return
 }
 
-func (m MapMetadata) GetFloat(key string) (v float64) {
+func GetFloat(md Metadata, key string) (v float64) {
-	switch vv := m[key].(type) {
+	if md == nil {
+		return
+	}
+
+	switch vv := md.Get(key).(type) {
 	case int:
 		return float64(vv)
 	case string:
@@ -78,27 +80,28 @@ func (m MapMetadata) GetFloat(key string) (v float64) {
 	return
 }
 
-func (m MapMetadata) GetDuration(key string) (v time.Duration) {
+func GetDuration(md Metadata, key string) (v time.Duration) {
-	if m != nil {
+	if md == nil {
-		switch vv := m[key].(type) {
+		return
-		case int:
+	}
-			return time.Duration(vv) * time.Second
+	switch vv := md.Get(key).(type) {
-		case string:
+	case int:
-			v, _ = time.ParseDuration(vv)
+		return time.Duration(vv) * time.Second
-		}
+	case string:
+		v, _ = time.ParseDuration(vv)
 	}
 	return
 }
 
-func (m MapMetadata) GetString(key string) (v string) {
+func GetString(md Metadata, key string) (v string) {
-	if m != nil {
+	if md != nil {
-		v, _ = m[key].(string)
+		v, _ = md.Get(key).(string)
 	}
 	return
 }
 
-func (m MapMetadata) GetStrings(key string) (ss []string) {
+func GetStrings(md Metadata, key string) (ss []string) {
-	if v, _ := m.Get(key).([]interface{}); len(v) > 0 {
+	if v, _ := md.Get(key).([]interface{}); len(v) > 0 {
 		for _, vv := range v {
 			if s, ok := vv.(string); ok {
 				ss = append(ss, s)
@@ -108,10 +111,29 @@ func (m MapMetadata) GetStrings(key string) (ss []string) {
 	return
 }
 
+func GetStringMap(md Metadata, key string) (m map[string]interface{}) {
+	switch vv := md.Get(key).(type) {
+	case map[string]interface{}:
+		return vv
+	case map[interface{}]interface{}:
+		m = make(map[string]interface{})
+		for k, v := range vv {
+			m[fmt.Sprintf("%v", k)] = v
+		}
+	}
+	return
+}
+
 func GetStringMapString(md Metadata, key string) (m map[string]string) {
-	if mm, _ := md.Get(key).(map[interface{}]interface{}); len(mm) > 0 {
+	switch vv := md.Get(key).(type) {
+	case map[string]interface{}:
 		m = make(map[string]string)
-		for k, v := range mm {
+		for k, v := range vv {
+			m[k] = fmt.Sprintf("%v", v)
+		}
+	case map[interface{}]interface{}:
+		m = make(map[string]string)
+		for k, v := range vv {
 			m[fmt.Sprintf("%v", k)] = fmt.Sprintf("%v", v)
 		}
 	}