package gost import ( "fmt" "net" "os/exec" "strings" "github.com/go-log/log" "github.com/songgao/water" ) func createTun(cfg TunConfig) (conn net.Conn, itf *net.Interface, err error) { 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 } mtu := cfg.MTU if mtu <= 0 { mtu = DefaultMTU } if err = exeCmd(fmt.Sprintf("ip link set dev %s mtu %d", ifce.Name(), mtu)); err != nil { log.Log(err) } if err = exeCmd(fmt.Sprintf("ip address add %s dev %s", cfg.Addr, ifce.Name())); err != nil { log.Log(err) } if err = exeCmd(fmt.Sprintf("ip link set dev %s up", ifce.Name())); err != nil { log.Log(err) } if err = addTunRoutes(ifce.Name(), cfg.Routes...); err != nil { return } itf, err = net.InterfaceByName(ifce.Name()) if err != nil { return } conn = &tunTapConn{ ifce: ifce, addr: &net.IPAddr{IP: ip}, } return } func createTap(cfg TapConfig) (conn net.Conn, itf *net.Interface, err error) { var ip net.IP if cfg.Addr != "" { ip, _, err = net.ParseCIDR(cfg.Addr) if err != nil { return } } ifce, err := water.New(water.Config{ DeviceType: water.TAP, PlatformSpecificParams: water.PlatformSpecificParams{ Name: cfg.Name, }, }) if err != nil { return } mtu := cfg.MTU if mtu <= 0 { mtu = DefaultMTU } if err = exeCmd(fmt.Sprintf("ip link set dev %s mtu %d", ifce.Name(), mtu)); err != nil { log.Log(err) } if cfg.Addr != "" { if err = exeCmd(fmt.Sprintf("ip address add %s dev %s", cfg.Addr, ifce.Name())); err != nil { log.Log(err) } } if err = exeCmd(fmt.Sprintf("ip link set dev %s up", ifce.Name())); err != nil { log.Log(err) } if err = addTapRoutes(ifce.Name(), cfg.Gateway, cfg.Routes...); err != nil { return } itf, err = net.InterfaceByName(ifce.Name()) if err != nil { return } conn = &tunTapConn{ ifce: ifce, addr: &net.IPAddr{IP: ip}, } return } func addTunRoutes(ifName string, routes ...IPRoute) error { for _, route := range routes { if route.Dest == nil { continue } cmd := fmt.Sprintf("ip route add %s dev %s", route.Dest.String(), ifName) log.Logf("[tun] %s", cmd) args := strings.Split(cmd, " ") if er := exec.Command(args[0], args[1:]...).Run(); er != nil { log.Logf("[tun] %s: %v", cmd, er) } } return nil } func addTapRoutes(ifName string, gw string, routes ...string) error { for _, route := range routes { if route == "" { continue } cmd := fmt.Sprintf("ip route add %s via %s dev %s", route, gw, ifName) log.Logf("[tap] %s", cmd) args := strings.Split(cmd, " ") if er := exec.Command(args[0], args[1:]...).Run(); er != nil { log.Logf("[tap] %s: %v", cmd, er) } } return nil } func exeCmd(cmd string) error { log.Log(cmd) args := strings.Split(cmd, " ") if err := exec.Command(args[0], args[1:]...).Run(); err != nil { return fmt.Errorf("%s: %v", cmd, err) } return nil }