mirror of
https://github.com/ericyan/shield.git
synced 2025-09-27 03:25:54 +08:00
72 lines
1.5 KiB
Go
72 lines
1.5 KiB
Go
package main
|
|
|
|
import (
|
|
"flag"
|
|
"io"
|
|
"log"
|
|
"os"
|
|
"os/signal"
|
|
"syscall"
|
|
|
|
"github.com/ericyan/shield/transport/udp"
|
|
"github.com/ericyan/shield/tuntap"
|
|
)
|
|
|
|
func main() {
|
|
bind := flag.String("bind", "0.0.0.0:1984", "ip and port to bind")
|
|
peer := flag.String("peer", "", "ip and port of the peer")
|
|
ip := flag.String("ip", "172.16.0.1/31", "ip of the tun device (in CIDR)")
|
|
mtu := flag.Int("mtu", 1350, "MTU of the tun device")
|
|
bufsize := flag.Int("bufsize", 1500, "size of the buffer")
|
|
flag.Parse()
|
|
|
|
// Set up the TUN device
|
|
tun, err := tuntap.NewTUN()
|
|
if err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
tun.SetMTU(*mtu)
|
|
addr, err := tuntap.ParseCIDR(*ip)
|
|
if err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
tun.AddAddr(addr)
|
|
tun.Up()
|
|
|
|
// Set up the UDP transport
|
|
udp, err := udp.New(*bind, *peer)
|
|
if err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
|
|
// Anything received from UDP goes to TUN
|
|
go func() {
|
|
buf := make([]byte, *bufsize)
|
|
_, err := io.CopyBuffer(tun, udp, buf)
|
|
if err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
}()
|
|
|
|
// Anything received from TUN goes to UDP
|
|
go func() {
|
|
buf := make([]byte, *bufsize)
|
|
_, err := io.CopyBuffer(udp, tun, buf)
|
|
if err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
}()
|
|
|
|
log.Printf("Listening on %s with peer %s", udp.LocalAddr(), udp.RemoteAddr())
|
|
addrs, err := tun.Addrs()
|
|
if err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
log.Printf("%s: %v", tun.Attrs().Name, addrs)
|
|
|
|
sig := make(chan os.Signal)
|
|
signal.Notify(sig, syscall.SIGINT, syscall.SIGTERM)
|
|
s := <-sig
|
|
log.Fatalf("Signal (%v) received, stopping\n", s)
|
|
}
|