tapdemo.go

package main

import (
	"fmt"
	"log"
	"time"

	"net"

	"github.com/lixin9311/water"
)

func main() {

	ifce, err := water.NewTAP("O_O")
	if err != nil {
		log.Println("Failed open")
		log.Fatal(err)
	}

	frame := make([]byte, 1500)
	conn, err := net.ListenPacket("udp", ":1234")
	if err != nil {
		log.Fatal(err)
	}
	addr, err := net.ResolveUDPAddr("udp", "192.168.1.9:1234")
	if err != nil {
		log.Fatal(err)
	}
	handleClient := func(conn net.PacketConn) {
		buffer := make([]byte, 1500)
		for {
			n, paddr, err := conn.ReadFrom(buffer)
			if err != nil {
				log.Fatal(err)
			}
			addr = paddr.(*net.UDPAddr)
			start := time.Now()
			if _, err := ifce.Write(buffer[:n]); err != nil {
				log.Println("Failed write")
				log.Fatal(err)
			}
			fmt.Printf("took %s\n", time.Since(start))
		}
	}
	go handleClient(conn)
	for {
		n, err := ifce.Read(frame)
		if err != nil {
			log.Println("Failed read")
			log.Fatal(err)
		}
		conn.WriteTo(frame[:n], addr)
	}
}