vtun/tun/tun.go
2021-12-15 17:16:29 +08:00

83 lines
2.7 KiB
Go

package tun
import (
"log"
"net"
"os"
"os/exec"
"runtime"
"strings"
"github.com/net-byte/vtun/common/config"
"github.com/net-byte/vtun/common/netutil"
"github.com/songgao/water"
)
func CreateTun(config config.Config) (iface *water.Interface) {
c := water.Config{DeviceType: water.TUN}
iface, err := water.New(c)
if err != nil {
log.Fatalln("failed to create tun interface:", err)
}
log.Println("interface created:", iface.Name())
configTun(config, iface)
return iface
}
func configTun(config config.Config, iface *water.Interface) {
os := runtime.GOOS
ip, ipNet, err := net.ParseCIDR(config.CIDR)
if err != nil {
log.Panicf("error cidr %v", config.CIDR)
}
if os == "linux" {
execCmd("/sbin/ip", "link", "set", "dev", iface.Name(), "mtu", "1500")
execCmd("/sbin/ip", "addr", "add", config.CIDR, "dev", iface.Name())
execCmd("/sbin/ip", "link", "set", "dev", iface.Name(), "up")
if config.GlobalMode {
physicalIface, gateway, _ := netutil.GetPhysicalInterface()
serverIP := netutil.LookupIP(strings.Split(config.ServerAddr, ":")[0])
if physicalIface != "" && serverIP != "" {
execCmd("/sbin/ip", "route", "add", "0.0.0.0/1", "dev", iface.Name())
execCmd("/sbin/ip", "route", "add", "128.0.0.0/1", "dev", iface.Name())
execCmd("/sbin/ip", "route", "add", strings.Join([]string{serverIP, "32"}, "/"), "via", gateway, "dev", physicalIface)
execCmd("/sbin/ip", "route", "add", strings.Join([]string{strings.Split(config.DNS, ":")[0], "32"}, "/"), "via", gateway, "dev", physicalIface)
}
}
} else if os == "darwin" {
gateway := ipNet.IP.To4()
gateway[3]++
execCmd("ifconfig", iface.Name(), "inet", ip.String(), gateway.String(), "up")
physicalIface, localGateway, _ := netutil.GetPhysicalInterface()
if config.GlobalMode {
serverIP := netutil.LookupIP(strings.Split(config.ServerAddr, ":")[0])
if physicalIface != "" && serverIP != "" {
execCmd("route", "add", serverIP, localGateway)
execCmd("route", "add", strings.Split(config.DNS, ":")[0], localGateway)
execCmd("route", "add", "0.0.0.0/1", "-interface", iface.Name())
execCmd("route", "add", "128.0.0.0/1", "-interface", iface.Name())
execCmd("route", "add", "default", gateway.String())
execCmd("route", "change", "default", gateway.String())
}
} else {
execCmd("route", "add", "default", localGateway)
execCmd("route", "change", "default", localGateway)
}
} else {
log.Printf("not support os:%v", os)
}
}
func execCmd(c string, args ...string) {
log.Printf("exec cmd: %v %v:", c, args)
cmd := exec.Command(c, args...)
cmd.Stderr = os.Stderr
cmd.Stdout = os.Stdout
cmd.Stdin = os.Stdin
err := cmd.Run()
if err != nil {
log.Println("failed to exec cmd:", err)
}
}