// Verify the secret key's range and if a test message signed with it verifies OK
// Returns nil if averything looks OK
func VerifyKeyPair(priv []byte, publ []byte) error {
const TestMessage = "Just some test message..."
hash := Sha2Sum([]byte(TestMessage))
pub_key, e := NewPublicKey(publ)
if e != nil {
return e
}
var key ecdsa.PrivateKey
key.D = new(big.Int).SetBytes(priv)
key.PublicKey = pub_key.PublicKey
if key.D.Cmp(big.NewInt(0)) == 0 {
return errors.New("pubkey value is zero")
}
if key.D.Cmp(secp256k1.N) != -1 {
return errors.New("pubkey value is too big")
}
r, s, err := ecdsa.Sign(rand.Reader, &key, hash[:])
if err != nil {
return errors.New("ecdsa.Sign failed: " + err.Error())
}
ok := ecdsa.Verify(&key.PublicKey, hash[:], r, s)
if !ok {
return errors.New("ecdsa.Sign Verify")
}
return nil
}
// Signs a specified transaction input
func (tx *Tx) Sign(in int, pk_script []byte, hash_type byte, pubkey, priv_key []byte) error {
if in >= len(tx.TxIn) {
return errors.New("tx.Sign() - input index overflow")
}
pub_key, er := NewPublicKey(pubkey)
if er != nil {
return er
}
// Load the key (private and public)
var key ecdsa.PrivateKey
key.D = new(big.Int).SetBytes(priv_key)
key.PublicKey = pub_key.PublicKey
//Calculate proper transaction hash
h := tx.SignatureHash(pk_script, in, hash_type)
// Sign
r, s, er := EcdsaSign(&key, h)
if er != nil {
return er
}
rb := r.Bytes()
sb := s.Bytes()
if rb[0] >= 0x80 {
rb = append([]byte{0x00}, rb...)
}
if sb[0] >= 0x80 {
sb = append([]byte{0x00}, sb...)
}
// Output the signing result into a buffer, in format expected by bitcoin protocol
busig := new(bytes.Buffer)
busig.WriteByte(0x30)
busig.WriteByte(byte(4 + len(rb) + len(sb)))
busig.WriteByte(0x02)
busig.WriteByte(byte(len(rb)))
busig.Write(rb)
busig.WriteByte(0x02)
busig.WriteByte(byte(len(sb)))
busig.Write(sb)
busig.WriteByte(0x01) // hash type
// Output the signature and the public key into tx.ScriptSig
buscr := new(bytes.Buffer)
buscr.WriteByte(byte(busig.Len()))
buscr.Write(busig.Bytes())
buscr.WriteByte(byte(len(pubkey)))
buscr.Write(pubkey)
// assign sign script ot the tx:
tx.TxIn[in].ScriptSig = buscr.Bytes()
return nil // no error
}
func UnmarshalCertificate(data []byte) Certificate {
priv := new(big.Int).SetBytes(data[:28])
pub := UnmarshalPublicCertificate(data[28:])
cert := new(ecdsa.PrivateKey)
cert.D = priv
cert.PublicKey = *pub
return cert
}
func (pk *PrivateKey) parseECDSAPrivateKey(data []byte) (err error) {
ecdsaPub := pk.PublicKey.PublicKey.(*ecdsa.PublicKey)
ecdsaPriv := new(ecdsa.PrivateKey)
ecdsaPriv.PublicKey = *ecdsaPub
buf := bytes.NewBuffer(data)
d, _, err := readMPI(buf)
if err != nil {
return
}
ecdsaPriv.D = new(big.Int).SetBytes(d)
pk.PrivateKey = ecdsaPriv
pk.Encrypted = false
pk.encryptedData = nil
return nil
}
// Verify the secret key's range and al if a test message signed with it verifies OK
func verify_key(priv []byte, publ []byte) bool {
const TestMessage = "Just some test message..."
hash := btc.Sha2Sum([]byte(TestMessage))
pub_key, e := btc.NewPublicKey(publ)
if e != nil {
println("NewPublicKey:", e.Error(), "\007")
os.Exit(1)
}
var key ecdsa.PrivateKey
key.D = new(big.Int).SetBytes(priv)
key.PublicKey = pub_key.PublicKey
if key.D.Cmp(big.NewInt(0)) == 0 {
println("pubkey value is zero")
return false
}
if key.D.Cmp(maxKeyVal) != -1 {
println("pubkey value is too big", hex.EncodeToString(publ))
return false
}
r, s, err := ecdsa.Sign(rand.Reader, &key, hash[:])
if err != nil {
println("ecdsa.Sign:", err.Error())
return false
}
ok := ecdsa.Verify(&key.PublicKey, hash[:], r, s)
if !ok {
println("The key pair does not verify!")
return false
}
return true
}
func multisig_sign() {
tx := raw_tx_from_file(*rawtx)
if tx == nil {
println("ERROR: Cannot decode the raw multisig transaction")
println("Always use -msign <addr> along with -raw multi2sign.txt")
return
}
ad2s, e := btc.NewAddrFromString(*multisign)
if e != nil {
println("BTC addr:", e.Error())
return
}
var privkey *ecdsa.PrivateKey
//var compr bool
for i := range publ_addrs {
if publ_addrs[i].Hash160 == ad2s.Hash160 {
privkey = new(ecdsa.PrivateKey)
pub, e := btc.NewPublicKey(publ_addrs[i].Pubkey)
if e != nil {
println("PubKey:", e.Error())
return
}
privkey.PublicKey = pub.PublicKey
privkey.D = new(big.Int).SetBytes(priv_keys[i][:])
//compr = compressed_key[i]
break
}
}
if privkey == nil {
println("You do not know a key for address", ad2s.String())
return
}
for i := range tx.TxIn {
ms, er := btc.NewMultiSigFromScript(tx.TxIn[i].ScriptSig)
if er != nil {
println("WARNING: Input", i, "- not multisig:", er.Error())
continue
}
hash := tx.SignatureHash(ms.P2SH(), i, btc.SIGHASH_ALL)
//fmt.Println("Input number", i, len(ms.Signatures), " - hash to sign:", hex.EncodeToString(hash))
btcsig := &btc.Signature{HashType: 0x01}
btcsig.R, btcsig.S, e = btc.EcdsaSign(privkey, hash)
if e != nil {
println(e.Error())
return
}
ms.Signatures = append(ms.Signatures, btcsig)
tx.TxIn[i].ScriptSig = ms.Bytes()
}
// Now re-order the signatures as they shall be:
for i := range tx.TxIn {
ms, er := btc.NewMultiSigFromScript(tx.TxIn[i].ScriptSig)
if er != nil {
//println(er.Error())
continue
}
hash := tx.SignatureHash(ms.P2SH(), i, btc.SIGHASH_ALL)
//fmt.Println("Input number", i, " - hash to sign:", hex.EncodeToString(hash))
//fmt.Println(" ... number of signatures:", len(ms.Signatures))
var sigs []*btc.Signature
for ki := range ms.PublicKeys {
//pk := btc.NewPublicKey(ms.PublicKeys[ki])
//fmt.Println(ki, hex.EncodeToString(ms.PublicKeys[ki]))
var sig *btc.Signature
for si := range ms.Signatures {
if btc.EcdsaVerify(ms.PublicKeys[ki], ms.Signatures[si].Bytes(), hash) {
//fmt.Println("Key number", ki, "has signature number", si)
sig = ms.Signatures[si]
break
}
}
if sig != nil {
sigs = append(sigs, sig)
} else if *verbose {
fmt.Println("WARNING: Key number", ki, "has no matching signature")
}
if !*allowextramsigns && uint(len(sigs)) >= ms.SigsNeeded {
break
}
}
if len(ms.Signatures) > len(sigs) {
fmt.Println("WARNING: Some signatures are obsolete and will be removed", len(ms.Signatures), "=>", len(sigs))
} else if len(ms.Signatures) < len(sigs) {
fmt.Println("It appears that same key is re-used.", len(sigs)-len(ms.Signatures), "more signatures were added")
}
ms.Signatures = sigs
tx.TxIn[i].ScriptSig = ms.Bytes()
}
write_tx_file(tx)
}
// prepare a signed transaction
func make_signed_tx() {
// Make an empty transaction
tx := new(btc.Tx)
tx.Version = 1
tx.Lock_time = 0
// Select as many inputs as we need to pay the full amount (with the fee)
var btcsofar uint64
var inpcnt uint
for inpcnt = 0; inpcnt < uint(len(unspentOuts)); inpcnt++ {
uo := UO(unspentOuts[inpcnt])
// add the input to our transaction:
tin := new(btc.TxIn)
tin.Input = *unspentOuts[inpcnt]
tin.Sequence = 0xffffffff
tx.TxIn = append(tx.TxIn, tin)
btcsofar += uo.Value
if btcsofar >= spendBtc+feeBtc {
break
}
}
changeBtc = btcsofar - (spendBtc + feeBtc)
fmt.Printf("Spending %d out of %d outputs...\n", inpcnt+1, len(unspentOuts))
// Build transaction outputs:
tx.TxOut = make([]*btc.TxOut, len(sendTo))
for o := range sendTo {
tx.TxOut[o] = &btc.TxOut{Value: sendTo[o].amount, Pk_script: sendTo[o].addr.OutScript()}
}
if changeBtc > 0 {
// Add one more output (with the change)
tx.TxOut = append(tx.TxOut, &btc.TxOut{Value: changeBtc, Pk_script: get_change_addr().OutScript()})
}
//fmt.Println("Unsigned:", hex.EncodeToString(tx.Serialize()))
for in := range tx.TxIn {
uo := UO(unspentOuts[in])
var found bool
for j := range publ_addrs {
if publ_addrs[j].Owns(uo.Pk_script) {
pub_key, e := btc.NewPublicKey(publ_addrs[j].Pubkey)
if e != nil {
println("NewPublicKey:", e.Error(), "\007")
os.Exit(1)
}
// Load the key (private and public)
var key ecdsa.PrivateKey
key.D = new(big.Int).SetBytes(priv_keys[j][:])
key.PublicKey = pub_key.PublicKey
//Calculate proper transaction hash
h := tx.SignatureHash(uo.Pk_script, in, btc.SIGHASH_ALL)
//fmt.Println("SignatureHash:", btc.NewUint256(h).String())
// Sign
r, s, err := ecdsa.Sign(rand.Reader, &key, h)
if err != nil {
println("Sign:", err.Error(), "\007")
os.Exit(1)
}
rb := r.Bytes()
sb := s.Bytes()
if rb[0] >= 0x80 { // I thinnk this is needed, thought I am not quite sure... :P
rb = append([]byte{0x00}, rb...)
}
if sb[0] >= 0x80 { // I thinnk this is needed, thought I am not quite sure... :P
sb = append([]byte{0x00}, sb...)
}
// Output the signing result into a buffer, in format expected by bitcoin protocol
busig := new(bytes.Buffer)
busig.WriteByte(0x30)
busig.WriteByte(byte(4 + len(rb) + len(sb)))
busig.WriteByte(0x02)
busig.WriteByte(byte(len(rb)))
busig.Write(rb)
busig.WriteByte(0x02)
busig.WriteByte(byte(len(sb)))
busig.Write(sb)
busig.WriteByte(0x01) // hash type
// Output the signature and the public key into tx.ScriptSig
buscr := new(bytes.Buffer)
buscr.WriteByte(byte(busig.Len()))
buscr.Write(busig.Bytes())
buscr.WriteByte(byte(len(publ_addrs[j].Pubkey)))
buscr.Write(publ_addrs[j].Pubkey)
// assign:
tx.TxIn[in].ScriptSig = buscr.Bytes()
found = true
break
}
}
if !found {
fmt.Println("You do not have private key for input number", hex.EncodeToString(uo.Pk_script), "\007")
os.Exit(1)
}
}
rawtx := tx.Serialize()
tx.Hash = btc.NewSha2Hash(rawtx)
hs := tx.Hash.String()
fmt.Println(hs)
f, _ := os.Create(hs[:8] + ".txt")
if f != nil {
f.Write([]byte(hex.EncodeToString(rawtx)))
f.Close()
fmt.Println("Transaction data stored in", hs[:8]+".txt")
}
f, _ = os.Create("balance/unspent.txt")
if f != nil {
for j := uint(0); j < uint(len(unspentOuts)); j++ {
if j > inpcnt {
fmt.Fprintln(f, unspentOuts[j], unspentOutsLabel[j])
}
}
fmt.Println(inpcnt, "spent output(s) removed from 'balance/unspent.txt'")
var addback int
for out := range tx.TxOut {
for j := range publ_addrs {
if publ_addrs[j].Owns(tx.TxOut[out].Pk_script) {
fmt.Fprintf(f, "%s-%03d # %.8f / %s\n", tx.Hash.String(), out,
float64(tx.TxOut[out].Value)/1e8, publ_addrs[j].String())
addback++
}
}
}
f.Close()
if addback > 0 {
f, _ = os.Create("balance/" + hs + ".tx")
if f != nil {
f.Write(rawtx)
f.Close()
}
fmt.Println(addback, "new output(s) appended to 'balance/unspent.txt'")
}
}
}
func sign_message() {
ad2s, e := btc.NewAddrFromString(*signaddr)
if e != nil {
println(e.Error())
return
}
var privkey *ecdsa.PrivateKey
for i := range publ_addrs {
if publ_addrs[i].Hash160 == ad2s.Hash160 {
privkey = new(ecdsa.PrivateKey)
pub, e := btc.NewPublicKey(publ_addrs[i].Pubkey)
if e != nil {
println(e.Error())
return
}
privkey.PublicKey = pub.PublicKey
privkey.D = new(big.Int).SetBytes(priv_keys[i][:])
break
}
}
if privkey == nil {
println("You do not have a private key for", ad2s.String())
return
}
var msg []byte
if *message == "" {
msg, _ = ioutil.ReadAll(os.Stdin)
} else {
msg = []byte(*message)
}
hash := make([]byte, 32)
btc.HashFromMessage(msg, hash)
btcsig := new(btc.Signature)
var sb [65]byte
sb[0] = 27
if !*uncompressed {
sb[0] += 4
}
btcsig.R, btcsig.S, e = ecdsa_Sign(privkey, hash)
if e != nil {
println(e.Error())
return
}
rd := btcsig.R.Bytes()
sd := btcsig.S.Bytes()
copy(sb[1+32-len(rd):], rd)
copy(sb[1+64-len(sd):], sd)
rpk := btcsig.RecoverPublicKey(hash[:], 0)
sa := btc.NewAddrFromPubkey(rpk.Bytes(!*uncompressed), ad2s.Version)
if sa.Hash160 == ad2s.Hash160 {
fmt.Println(base64.StdEncoding.EncodeToString(sb[:]))
return
}
rpk = btcsig.RecoverPublicKey(hash[:], 1)
sa = btc.NewAddrFromPubkey(rpk.Bytes(!*uncompressed), ad2s.Version)
if sa.Hash160 == ad2s.Hash160 {
sb[0]++
fmt.Println(base64.StdEncoding.EncodeToString(sb[:]))
return
}
println("Something went wrong. The message has not been signed.")
}
// this function signs either a message or a raw transaction hash
func sign_message() {
var hash []byte
if *signhash != "" {
var er error
hash, er = hex.DecodeString(*signhash)
if er != nil {
println("Incorrect content of -hash parameter")
println(er.Error())
return
}
}
ad2s, e := btc.NewAddrFromString(*signaddr)
if e != nil {
println(e.Error())
if *signhash != "" {
println("Always use -sign <addr> along with -hash <msghash>")
}
return
}
var privkey *ecdsa.PrivateKey
var compr bool
for i := range publ_addrs {
if publ_addrs[i].Hash160 == ad2s.Hash160 {
privkey = new(ecdsa.PrivateKey)
pub, e := btc.NewPublicKey(publ_addrs[i].Pubkey)
if e != nil {
println(e.Error())
return
}
privkey.PublicKey = pub.PublicKey
privkey.D = new(big.Int).SetBytes(priv_keys[i][:])
compr = compressed_key[i]
// Sign raw hash?
if hash != nil {
txsig := new(btc.Signature)
txsig.HashType = 0x01
txsig.R, txsig.S, e = btc.EcdsaSign(privkey, hash)
if e != nil {
println(e.Error())
return
}
fmt.Println("PublicKey:", hex.EncodeToString(publ_addrs[i].Pubkey))
fmt.Println(hex.EncodeToString(txsig.Bytes()))
return
}
break
}
}
if privkey == nil {
println("You do not have a private key for", ad2s.String())
return
}
var msg []byte
if *message == "" {
msg, _ = ioutil.ReadAll(os.Stdin)
} else {
msg = []byte(*message)
}
hash = make([]byte, 32)
btc.HashFromMessage(msg, hash)
btcsig := new(btc.Signature)
var sb [65]byte
sb[0] = 27
if compr {
sb[0] += 4
}
btcsig.R, btcsig.S, e = btc.EcdsaSign(privkey, hash)
if e != nil {
println(e.Error())
return
}
rd := btcsig.R.Bytes()
sd := btcsig.S.Bytes()
copy(sb[1+32-len(rd):], rd)
copy(sb[1+64-len(sd):], sd)
rpk := btcsig.RecoverPublicKey(hash[:], 0)
sa := btc.NewAddrFromPubkey(rpk.Bytes(compr), ad2s.Version)
if sa.Hash160 == ad2s.Hash160 {
fmt.Println(base64.StdEncoding.EncodeToString(sb[:]))
return
}
rpk = btcsig.RecoverPublicKey(hash[:], 1)
sa = btc.NewAddrFromPubkey(rpk.Bytes(compr), ad2s.Version)
if sa.Hash160 == ad2s.Hash160 {
sb[0]++
fmt.Println(base64.StdEncoding.EncodeToString(sb[:]))
return
}
println("Something went wrong. The message has not been signed.")
}
