Example #1
0
func main() {
	var h *pcap.Pcap
	var err string
	var dumper *pcap.PcapDumper

	if *offlinefn == "" {
		h, err = pcap.Openlive(*device, 1500, true, 0)
	} else {
		h, err = pcap.Openoffline(*offlinefn)
	}

	if *writefile != "" {
		dumper = pcap.NewPcapDumper(h, *writefile)
	}

	if h == nil {
		fmt.Printf("Warning: no devices found : %s\n", err)
		os.Exit(-1)
	}

	h.Setfilter(expr)

	for pkt := h.Next(); pkt != nil; pkt = h.Next() {
		packet := pcap.DecodeEthernetPkt(pkt)
		if dumper == nil {
			pcap.PrintDecodedPkt(packet)
		} else {
			dumper.Dump(packet.PcapPktHdr)
		}
	}
}
Example #2
0
func main() {
	var device *string = flag.String("d", "", "device")
	var file *string = flag.String("r", "", "file")
	var expr *string = flag.String("e", "", "filter expression")

	flag.Parse()

	var h *pcap.Pcap
	var err string

	ifs, err := pcap.Findalldevs()
	if len(ifs) == 0 {
		fmt.Printf("Warning: no devices found : %s\n", err)
	} else {
		for i := 0; i < len(ifs); i++ {
			fmt.Printf("dev %d: %s (%s)\n", i+1, ifs[i].Name, ifs[i].Description)
		}
	}

	if *device != "" {
		h, err = pcap.Openlive(*device, 65535, true, 0)
		if h == nil {
			fmt.Printf("Openlive(%s) failed: %s\n", *device, err)
			return
		}
	} else if *file != "" {
		h, err = pcap.Openoffline(*file)
		if h == nil {
			fmt.Printf("Openoffline(%s) failed: %s\n", *file, err)
			return
		}
	} else {
		fmt.Printf("usage: pcaptest [-d <device> | -r <file>]\n")
		return
	}

	fmt.Printf("pcap version: %s\n", pcap.Version())

	if *expr != "" {
		fmt.Printf("Setting filter: %s\n", *expr)
		err := h.Setfilter(*expr)
		if err != "" {
			fmt.Printf("Warning: setting filter failed: %s\n", err)
		}
	}

	for pkt := h.Next(); pkt != nil; pkt = h.Next() {
		fmt.Printf("time: %d.%06d (%s) caplen: %d len: %d\nData:",
			int64(pkt.Time.Sec), int64(pkt.Time.Usec),
			time.SecondsToLocalTime(int64(pkt.Time.Sec)).String(), int64(pkt.Caplen), int64(pkt.Len))
		for i := uint32(0); i < pkt.Caplen; i++ {
			if i%32 == 0 {
				fmt.Printf("\n")
			}
			if 32 <= pkt.Data[i] && pkt.Data[i] <= 126 {
				fmt.Printf("%c", pkt.Data[i])
			} else {
				fmt.Printf(".")
			}
		}
		fmt.Printf("\n\n")
	}

}