func addHandler(h *pcap.Pcap, dumper *pcap.PcapDumper) {
c := make(chan os.Signal, 1)
signal.Notify(c, os.Interrupt)
go func() {
for sig := range c {
fmt.Fprintln(os.Stderr, "tcpdump: received signal:", sig)
if os.Interrupt == sig {
h.PcapDumpClose(dumper)
h.Close()
os.Exit(1)
}
}
}()
}
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.Unix(int64(pkt.Time.Sec), 0).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")
}
}