github.com/jeffallen/go-ethereum@v1.1.4-0.20150910155051-571d3236c49c/cmd/bootnode/main.go (about) 1 // Copyright 2015 The go-ethereum Authors 2 // This file is part of go-ethereum. 3 // 4 // go-ethereum is free software: you can redistribute it and/or modify 5 // it under the terms of the GNU General Public License as published by 6 // the Free Software Foundation, either version 3 of the License, or 7 // (at your option) any later version. 8 // 9 // go-ethereum is distributed in the hope that it will be useful, 10 // but WITHOUT ANY WARRANTY; without even the implied warranty of 11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 // GNU General Public License for more details. 13 // 14 // You should have received a copy of the GNU General Public License 15 // along with go-ethereum. If not, see <http://www.gnu.org/licenses/>. 16 17 // bootnode runs a bootstrap node for the Ethereum Discovery Protocol. 18 package main 19 20 import ( 21 "crypto/ecdsa" 22 "encoding/hex" 23 "flag" 24 "fmt" 25 "io/ioutil" 26 "log" 27 "os" 28 29 "github.com/ethereum/go-ethereum/crypto" 30 "github.com/ethereum/go-ethereum/logger" 31 "github.com/ethereum/go-ethereum/p2p/discover" 32 "github.com/ethereum/go-ethereum/p2p/nat" 33 ) 34 35 func main() { 36 var ( 37 listenAddr = flag.String("addr", ":30301", "listen address") 38 genKey = flag.String("genkey", "", "generate a node key and quit") 39 nodeKeyFile = flag.String("nodekey", "", "private key filename") 40 nodeKeyHex = flag.String("nodekeyhex", "", "private key as hex (for testing)") 41 natdesc = flag.String("nat", "none", "port mapping mechanism (any|none|upnp|pmp|extip:<IP>)") 42 43 nodeKey *ecdsa.PrivateKey 44 err error 45 ) 46 flag.Parse() 47 logger.AddLogSystem(logger.NewStdLogSystem(os.Stdout, log.LstdFlags, logger.DebugLevel)) 48 49 if *genKey != "" { 50 writeKey(*genKey) 51 os.Exit(0) 52 } 53 54 natm, err := nat.Parse(*natdesc) 55 if err != nil { 56 log.Fatalf("-nat: %v", err) 57 } 58 switch { 59 case *nodeKeyFile == "" && *nodeKeyHex == "": 60 log.Fatal("Use -nodekey or -nodekeyhex to specify a private key") 61 case *nodeKeyFile != "" && *nodeKeyHex != "": 62 log.Fatal("Options -nodekey and -nodekeyhex are mutually exclusive") 63 case *nodeKeyFile != "": 64 if nodeKey, err = crypto.LoadECDSA(*nodeKeyFile); err != nil { 65 log.Fatalf("-nodekey: %v", err) 66 } 67 case *nodeKeyHex != "": 68 if nodeKey, err = crypto.HexToECDSA(*nodeKeyHex); err != nil { 69 log.Fatalf("-nodekeyhex: %v", err) 70 } 71 } 72 73 if _, err := discover.ListenUDP(nodeKey, *listenAddr, natm, ""); err != nil { 74 log.Fatal(err) 75 } 76 select {} 77 } 78 79 func writeKey(target string) { 80 key, err := crypto.GenerateKey() 81 if err != nil { 82 log.Fatal("could not generate key: %v", err) 83 } 84 b := crypto.FromECDSA(key) 85 if target == "-" { 86 fmt.Println(hex.EncodeToString(b)) 87 } else { 88 if err := ioutil.WriteFile(target, b, 0600); err != nil { 89 log.Fatal("write error: ", err) 90 } 91 } 92 }