// 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", ":42787", "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.Var(glog.GetVerbosity(), "verbosity", "log verbosity (0-9)")
flag.Var(glog.GetVModule(), "vmodule", "log verbosity pattern")
glog.SetToStderr(true)
flag.Parse()
if *genKey != "" {
key, err := crypto.GenerateKey()
if err != nil {
utils.Fatalf("could not generate key: %v", err)
}
if err := crypto.SaveECDSA(*genKey, key); err != nil {
utils.Fatalf("%v", err)
}
os.Exit(0)
}
natm, err := nat.Parse(*natdesc)
if err != nil {
utils.Fatalf("-nat: %v", err)
}
switch {
case *nodeKeyFile == "" && *nodeKeyHex == "":
utils.Fatalf("Use -nodekey or -nodekeyhex to specify a private key")
case *nodeKeyFile != "" && *nodeKeyHex != "":
utils.Fatalf("Options -nodekey and -nodekeyhex are mutually exclusive")
case *nodeKeyFile != "":
if nodeKey, err = crypto.LoadECDSA(*nodeKeyFile); err != nil {
utils.Fatalf("-nodekey: %v", err)
}
case *nodeKeyHex != "":
if nodeKey, err = crypto.HexToECDSA(*nodeKeyHex); err != nil {
utils.Fatalf("-nodekeyhex: %v", err)
}
}
if _, err := discover.ListenUDP(nodeKey, *listenAddr, natm, ""); err != nil {
utils.Fatalf("%v", err)
}
select {}
}