62 lines
1.1 KiB
Go
62 lines
1.1 KiB
Go
package main
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import (
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"flag"
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"fmt"
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"log"
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"net"
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)
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func main() {
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var addr, dest string
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flag.StringVar(&addr, "addr", ":9999", "listen address")
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flag.StringVar(&dest, "dest", "", "destination")
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flag.Parse()
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if dest == "" {
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fmt.Println("Error: missing -dest")
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fmt.Println("run with -h to see options.")
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return
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}
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log.Printf("Listening to %s - Relaying to %s", addr, dest)
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raddr, err := net.ResolveUDPAddr("udp", dest)
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if err != nil {
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panic(err)
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}
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udpConn, err := net.DialUDP("udp", nil, raddr)
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if err != nil {
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panic(err)
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}
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defer udpConn.Close()
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laddr, err := net.ResolveUDPAddr("udp", addr)
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if err != nil {
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panic(err)
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}
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l, err := net.ListenUDP("udp", laddr)
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if err != nil {
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panic(err)
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}
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defer l.Close()
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for {
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buf := make([]byte, 1024)
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n, raddr, err := l.ReadFrom(buf)
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log.Printf("received packet %d\n", n)
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if err != nil {
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panic(err)
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}
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if _, err := udpConn.Write(buf[0:n]); err != nil {
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log.Printf("error relaying data: %s\n", err)
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}
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log.Printf("%d bytes relayed from %s to destination.\n", n, raddr.String())
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}
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}
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