// ReadKeyPair reads an ECDSA keypair a file in JSON object format.
// Example JSON input:
// {
// "privkey": "..."
// }
// It also checks if a pubkey is in the keyring and, if not, appends it to the
// keyring.
func ReadKeyPair(filename string) (*ecdsa.PrivateKey, error) {
// Load the file
f, err := ioutil.ReadFile(filename)
if err != nil {
fError := errors.New("os.Open: Couldn't open keypair file.")
return nil, fError
}
// Unmarshall the loaded file into a map.
var keyMap = make(map[string]string)
var pubkey *ecdsa.PublicKey
var privkey *ecdsa.PrivateKey
err = json.Unmarshal(f, &keyMap)
if err != nil {
jsonError := errors.New("json error: Couldn't unmarshall keypair file.")
return nil, jsonError
}
privBytes, errDecode := hex.DecodeString(keyMap["privkey"])
if errDecode != nil {
decodeError := errors.New("decode error: Couldn't decode hex for privkey.")
return nil, decodeError
}
// PrivKeyFromBytes doesn't return an error, so this could possibly be ugly.
privkeyBtcec, _ := btcec.PrivKeyFromBytes(btcec.S256(), privBytes)
pubBytes, errDecode := hex.DecodeString(keyMap["pubkey"])
if errDecode != nil {
decodeError := errors.New("decode error: Couldn't decode hex for privkey.")
return nil, decodeError
}
pubkeyBtcec, errParse := btcec.ParsePubKey(pubBytes, btcec.S256())
if errParse != nil {
return nil, errParse
}
// Assign the things to return
pubkey = &ecdsa.PublicKey{pubkeyBtcec.Curve,
pubkeyBtcec.X,
pubkeyBtcec.Y}
privkey = &ecdsa.PrivateKey{*pubkey, privkeyBtcec.D}
return privkey, nil
}
func main() {
// Print header
fmt.Printf("%64s %34s %34s\n", "Private", "Public", "Public Compressed")
// Initialise big numbers with small numbers
count, one := big.NewInt(0), big.NewInt(1)
// Create a slice to pad our count to 32 bytes
padded := make([]byte, 32)
// Loop forever because we're never going to hit the end anyway
for {
// Increment our counter
count.Add(count, one)
// Copy count value's bytes to padded slice
copy(padded[32-len(count.Bytes()):], count.Bytes())
// Get public key
_, public := btcec.PrivKeyFromBytes(btcec.S256(), padded)
// Get compressed and uncompressed addresses
caddr, _ := btcutil.NewAddressPubKey(public.SerializeCompressed(), &btcnet.MainNetParams)
uaddr, _ := btcutil.NewAddressPubKey(public.SerializeUncompressed(), &btcnet.MainNetParams)
// Print keys
fmt.Printf("%x %34s %34s\n", padded, uaddr.EncodeAddress(), caddr.EncodeAddress())
}
}
func compute(count *big.Int) (keys [ResultsPerPage]Key, length int) {
var padded [32]byte
var i int
for i = 0; i < ResultsPerPage; i++ {
// Increment our counter
count.Add(count, one)
// Check to make sure we're not out of range
if count.Cmp(total) > 0 {
break
}
// Copy count value's bytes to padded slice
copy(padded[32-len(count.Bytes()):], count.Bytes())
// Get private and public keys
privKey, public := btcec.PrivKeyFromBytes(btcec.S256(), padded[:])
// Get compressed and uncompressed addresses for public key
caddr, _ := btcutil.NewAddressPubKey(public.SerializeCompressed(), &btcnet.MainNetParams)
uaddr, _ := btcutil.NewAddressPubKey(public.SerializeUncompressed(), &btcnet.MainNetParams)
// Encode addresses
wif, _ := btcutil.NewWIF(privKey, &btcnet.MainNetParams, false)
keys[i].private = wif.String()
keys[i].number = count.String()
keys[i].compressed = caddr.EncodeAddress()
keys[i].uncompressed = uaddr.EncodeAddress()
}
return keys, i
}
// getArgs parses command line args and asserts that a private key and an
// address are present and correctly formatted.
func getArgs() requiredArgs {
flag.Parse()
if *a == "" || *k == "" || *t == "" || *v == -1 {
fmt.Println("\nThis tool generates a bitcoin transaction that moves coins from an input to an output.\n" +
"You must provide a key, an address, a transaction id (the hash\n" +
"of a tx) and the index into the outputs of that tx that fund your\n" +
"address! Use http://blockchain.info/pushtx to send the raw transaction.\n")
flag.PrintDefaults()
fmt.Println("")
os.Exit(0)
}
pkBytes, err := hex.DecodeString(*k)
if err != nil {
log.Fatal(err)
}
privKey, _ := btcec.PrivKeyFromBytes(btcec.S256(), pkBytes)
addr, err := btcutil.DecodeAddress(*a, &btcnet.MainNetParams)
if err != nil {
log.Fatal(err)
}
txid, err := btcwire.NewShaHashFromStr(*t)
args := requiredArgs{
txid: txid,
vout: uint32(*v),
toAddress: addr,
privKey: privKey,
}
return args
}
func generateKeyPair() (*btcec.PublicKey, *btcec.PrivateKey) {
// Generate a private key, use the curve secpc256k1 and kill the program on
// any errors
priv, err := btcec.NewPrivateKey(btcec.S256())
if err != nil {
// There was an error. Log it and bail out
log.Fatal(err)
}
return priv.PubKey(), priv
}
// ReadKeyRing reads a key ring of public keys from a file in JSON object format,
// and also inserts the pubkey of a keypair if it's not already present (handles
// bug in URS implementation).
func ReadKeyRing(filename string, kp *ecdsa.PrivateKey) (*PublicKeyRing, error) {
// Load the file
f, err := ioutil.ReadFile(filename)
if err != nil {
fError := errors.New("os.Open: Couldn't open keyring file.")
return nil, fError
}
// Unmarshall the loaded file into a map
var keyMap = make(map[string]string)
err = json.Unmarshal(f, &keyMap)
if err != nil {
str := fmt.Sprintf("json error: Couldn't unmarshall keyring file.", err)
jsonError := errors.New(str)
return nil, jsonError
}
kr := NewPublicKeyRing(uint(len(keyMap)))
// Stick the pubkeys into the keyring as long as it doesn't belong to the
// keypair given.
for i := 0; i < len(keyMap); i++ {
pkBytes, errDecode := hex.DecodeString(keyMap[strconv.Itoa(i)])
if errDecode != nil {
decodeError := errors.New("decode error: Couldn't decode hex.")
return nil, decodeError
}
pubkey, errParse := btcec.ParsePubKey(pkBytes, btcec.S256())
if errParse != nil {
return nil, errParse
}
ecdsaPubkey := ecdsa.PublicKey{pubkey.Curve, pubkey.X, pubkey.Y}
if kp == nil || !CmpPubKey(&kp.PublicKey, &ecdsaPubkey) {
kr.Add(ecdsaPubkey)
} else {
kr.Add(kp.PublicKey)
}
}
// Stick the keypair in if it's missing.
if kp != nil && !kr.keyInKeyRing(&kp.PublicKey) {
kr.Add(kp.PublicKey)
}
return kr, nil
}
// generateKeyPair generates and stores an ECDSA keypair to a file.
func generateKeyPair(filename string) error {
// Generate keypairs.
aKeypair, err := ecdsa.GenerateKey(btcec.S256(), crand.Reader)
if err != nil {
return err
}
pubkeyBtcec := btcec.PublicKey{aKeypair.PublicKey.Curve,
aKeypair.PublicKey.X,
aKeypair.PublicKey.Y}
keypairBtcec := btcec.PrivateKey{aKeypair.PublicKey, aKeypair.D}
// Create a map to json marshal
keypairMap := make(map[string]string)
keypairMap["pubkey"] = hex.EncodeToString(pubkeyBtcec.SerializeCompressed())
keypairMap["privkey"] = hex.EncodeToString(keypairBtcec.Serialize())
// Store the address in case anyone wants to use it for BTC
pkh, err := btcutil.NewAddressPubKey(pubkeyBtcec.SerializeCompressed(),
&btcnet.MainNetParams)
if err != nil {
return err
}
keypairMap["address"] = pkh.EncodeAddress()
b, err := json.Marshal(keypairMap)
if err != nil {
return err
}
err = ioutil.WriteFile(filename, b, 0644)
if err != nil {
return err
}
return nil
}