tun: replace ip command with syscall

go.mod

@@ -10,6 +10,7 @@ require (
 	github.com/bifurcation/mint v0.0.0-20181105071958-a14404e9a861 // indirect
 	github.com/cheekybits/genny v1.0.0 // indirect
 	github.com/dchest/siphash v1.2.1 // indirect
+	github.com/docker/libcontainer v2.2.1+incompatible // indirect
 	github.com/ginuerzh/gosocks4 v0.0.1
 	github.com/ginuerzh/gosocks5 v0.2.0
 	github.com/ginuerzh/tls-dissector v0.0.1
@@ -25,6 +26,7 @@ require (
 	github.com/lucas-clemente/quic-go v0.10.0
 	github.com/lucas-clemente/quic-go-certificates v0.0.0-20160823095156-d2f86524cced // indirect
 	github.com/miekg/dns v1.1.3
+	github.com/milosgajdos83/tenus v0.0.0-20190415114537-1f3ed00ae7d8
 	github.com/onsi/ginkgo v1.7.0 // indirect
 	github.com/onsi/gomega v1.4.3 // indirect
 	github.com/pkg/errors v0.8.1 // indirect

go.sum

@@ -16,6 +16,8 @@ github.com/dchest/siphash v1.2.0 h1:YWOShuhvg0GqbQpMa60QlCGtEyf7O7HC1Jf0VjdQ60M=
 github.com/dchest/siphash v1.2.0/go.mod h1:q+IRvb2gOSrUnYoPqHiyHXS0FOBBOdl6tONBlVnOnt4=
 github.com/dchest/siphash v1.2.1 h1:4cLinnzVJDKxTCl9B01807Yiy+W7ZzVHj/KIroQRvT4=
 github.com/dchest/siphash v1.2.1/go.mod h1:q+IRvb2gOSrUnYoPqHiyHXS0FOBBOdl6tONBlVnOnt4=
+github.com/docker/libcontainer v2.2.1+incompatible h1:++SbbkCw+X8vAd4j2gOCzZ2Nn7s2xFALTf7LZKmM1/0=
+github.com/docker/libcontainer v2.2.1+incompatible/go.mod h1:osvj61pYsqhNCMLGX31xr7klUBhHb/ZBuXS0o1Fvwbw=
 github.com/fsnotify/fsnotify v1.4.7 h1:IXs+QLmnXW2CcXuY+8Mzv/fWEsPGWxqefPtCP5CnV9I=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/ginuerzh/gosocks4 v0.0.1 h1:ojDKUyz+uaEeRm2usY1cyQiXTqJqrKxfeE6SVBXq4m0=
@@ -52,6 +54,8 @@ github.com/lucas-clemente/quic-go-certificates v0.0.0-20160823095156-d2f86524cce
 github.com/lucas-clemente/quic-go-certificates v0.0.0-20160823095156-d2f86524cced/go.mod h1:NCcRLrOTZbzhZvixZLlERbJtDtYsmMw8Jc4vS8Z0g58=
 github.com/miekg/dns v1.1.3 h1:1g0r1IvskvgL8rR+AcHzUA+oFmGcQlaIm4IqakufeMM=
 github.com/miekg/dns v1.1.3/go.mod h1:W1PPwlIAgtquWBMBEV9nkV9Cazfe8ScdGz/Lj7v3Nrg=
+github.com/milosgajdos83/tenus v0.0.0-20190415114537-1f3ed00ae7d8 h1:4WFQEfEJ7zaHYViIVM2Cd6tnQOOhiEHbmQtlcV7aOpc=
+github.com/milosgajdos83/tenus v0.0.0-20190415114537-1f3ed00ae7d8/go.mod h1:G95Wwn625/q6JCCytI4VR/a5VtPwrtI0B+Q1Gi38QLA=
 github.com/onsi/ginkgo v1.6.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
 github.com/onsi/ginkgo v1.7.0 h1:WSHQ+IS43OoUrWtD1/bbclrwK8TTH5hzp+umCiuxHgs=
 github.com/onsi/ginkgo v1.7.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=

tun.go

@@ -5,8 +5,6 @@ import (
 	"io"
 	"net"
 	"os"
-	"os/exec"
-	"strconv"
 	"sync"
 	"time"
 
@@ -26,6 +24,7 @@ type TunConfig struct {
 type tunHandler struct {
 	raddr   string
 	options *HandlerOptions
+	ipNet   *net.IPNet
 }
 
 // TunHandler creates a handler for tun tunnel.
@@ -92,50 +91,8 @@ func (h *tunHandler) Handle(conn net.Conn) {
 }
 
 func (h *tunHandler) createTun() (conn net.Conn, err error) {
-	cfg := h.options.TunConfig
-
-	ip, _, err := net.ParseCIDR(cfg.Addr)
-	if err != nil {
-		return
-	}
-
-	ifce, err := water.New(water.Config{
-		DeviceType: water.TUN,
-		PlatformSpecificParams: water.PlatformSpecificParams{
-			Name: cfg.Name,
-		},
-	})
-	if err != nil {
-		return
-	}
-
-	setup := func(args ...string) error {
-		cmd := exec.Command("/sbin/ip", args...)
-		cmd.Stdout = os.Stdout
-		cmd.Stderr = os.Stderr
-		return cmd.Run()
-	}
-
-	mtu := cfg.MTU
-	if mtu <= 0 {
-		mtu = DefaultMTU
-	}
-
-	if err = setup("link", "set", "dev", ifce.Name(), "mtu", strconv.Itoa(mtu)); err != nil {
-		return
-	}
-	if err = setup("addr", "add", cfg.Addr, "dev", ifce.Name()); err != nil {
-		return
-	}
-	if err = setup("link", "set", "dev", ifce.Name(), "up"); err != nil {
-		return
-	}
-
-	tc := &tunConn{
-		ifce: ifce,
-		addr: &net.IPAddr{IP: ip},
-	}
-	return tc, nil
+	conn, h.ipNet, err = createTun(h.options.TunConfig)
+	return
 }
 
 func (h *tunHandler) transportTun(tun net.Conn, conn net.PacketConn, raddr net.Addr) error {
@@ -223,10 +180,12 @@ func (h *tunHandler) transportTun(tun net.Conn, conn net.PacketConn, raddr net.A
 						header.Len, header.TotalLen, header.ID, header.Flags, header.Protocol)
 				}
 
-				if actual, loaded := routes.LoadOrStore(header.Src.String(), addr); loaded {
-					if actual.(net.Addr).String() != addr.String() {
-						log.Logf("[tun] %s <- %s: unexpected address mapping %s -> %s(actual %s)",
-							tun.LocalAddr(), addr, header.Dst.String(), addr, actual.(net.Addr).String())
+				if h.ipNet != nil && h.ipNet.Contains(header.Src) {
+					if actual, loaded := routes.LoadOrStore(header.Src.String(), addr); loaded {
+						if actual.(net.Addr).String() != addr.String() {
+							log.Logf("[tun] %s <- %s: unexpected address mapping %s -> %s(actual %s)",
+								tun.LocalAddr(), addr, header.Dst, addr, actual.(net.Addr))
+						}
 					}
 				}
 

tun_darwin.go

+// +build darwin
+
+package gost
+
+import (
+	"net"
+	"os/exec"
+	"strconv"
+
+	"github.com/songgao/water"
+)
+
+func createTun(cfg TunConfig) (conn net.Conn, ipNet *net.IPNet, err error) {
+	ip, ipNet, err := net.ParseCIDR(cfg.Addr)
+	if err != nil {
+		return
+	}
+
+	ifce, err := water.New(water.Config{
+		DeviceType: water.TUN,
+	})
+	if err != nil {
+		return
+	}
+
+	mtu := cfg.MTU
+	if mtu <= 0 {
+		mtu = DefaultMTU
+	}
+
+	if err = exec.Command(
+		"ifconfig", ifce.Name(),
+		"inet", cfg.Addr,
+		"mtu", strconv.Itoa(mtu),
+		"up").Run(); err != nil {
+		return
+	}
+
+	conn = &tunConn{
+		ifce: ifce,
+		addr: &net.IPAddr{IP: ip},
+	}
+	return
+}

tun_linux.go

+// +build linux
+
+package gost
+
+import (
+	"net"
+
+	"github.com/milosgajdos83/tenus"
+	"github.com/songgao/water"
+)
+
+func createTun(cfg TunConfig) (conn net.Conn, ipNet *net.IPNet, err error) {
+	ip, ipNet, err := net.ParseCIDR(cfg.Addr)
+	if err != nil {
+		return
+	}
+
+	ifce, err := water.New(water.Config{
+		DeviceType: water.TUN,
+		PlatformSpecificParams: water.PlatformSpecificParams{
+			Name: cfg.Name,
+		},
+	})
+	if err != nil {
+		return
+	}
+
+	link, err := tenus.NewLinkFrom(ifce.Name())
+	if err != nil {
+		return
+	}
+
+	mtu := cfg.MTU
+	if mtu <= 0 {
+		mtu = DefaultMTU
+	}
+	if err = link.SetLinkMTU(mtu); err != nil {
+		return
+	}
+	if err = link.SetLinkIp(ip, ipNet); err != nil {
+		return
+	}
+	if err = link.SetLinkUp(); err != nil {
+		return
+	}
+
+	conn = &tunConn{
+		ifce: ifce,
+		addr: &net.IPAddr{IP: ip},
+	}
+	return
+}

tun_win.go

+// +build windows
+
+package gost
+
+import (
+	"errors"
+	"net"
+)
+
+func createTun(cfg TunConfig) (conn net.Conn, ipNet *net.IPNet, err error) {
+	err = errors.New("tun is not supported on Windows")
+	return
+}