// MakeNAT creates a port mapper from set command line flags.
func MakeNAT(ctx *cli.Context) nat.Interface {
natif, err := nat.Parse(ctx.GlobalString(NATFlag.Name))
if err != nil {
Fatalf("Option %s: %v", NATFlag.Name, err)
}
return natif
}
func main() {
var (
listenAddr = flag.String("addr", ":30301", "listen address")
genKey = flag.String("genkey", "", "generate a node key and quit")
nodeKeyFile = flag.String("nodekey", "", "private key filename")
nodeKeyHex = flag.String("nodekeyhex", "", "private key as hex (for testing)")
natdesc = flag.String("nat", "none", "port mapping mechanism (any|none|upnp|pmp|extip:<IP>)")
nodeKey *ecdsa.PrivateKey
err error
)
flag.Parse()
logger.AddLogSystem(logger.NewStdLogSystem(os.Stdout, log.LstdFlags, logger.DebugLevel))
if *genKey != "" {
writeKey(*genKey)
os.Exit(0)
}
natm, err := nat.Parse(*natdesc)
if err != nil {
log.Fatalf("-nat: %v", err)
}
switch {
case *nodeKeyFile == "" && *nodeKeyHex == "":
log.Fatal("Use -nodekey or -nodekeyhex to specify a private key")
case *nodeKeyFile != "" && *nodeKeyHex != "":
log.Fatal("Options -nodekey and -nodekeyhex are mutually exclusive")
case *nodeKeyFile != "":
if nodeKey, err = crypto.LoadECDSA(*nodeKeyFile); err != nil {
log.Fatalf("-nodekey: %v", err)
}
case *nodeKeyHex != "":
if nodeKey, err = crypto.HexToECDSA(*nodeKeyHex); err != nil {
log.Fatalf("-nodekeyhex: %v", err)
}
}
if _, err := discover.ListenUDP(nodeKey, *listenAddr, natm, ""); err != nil {
log.Fatal(err)
}
select {}
}