// sign a multisig transaction with a specific key
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
}
k := address_to_key(*multisign)
if k == nil {
println("You do not know a key for address", *multisign)
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))
r, s, e := btc.EcdsaSign(k.Key, hash)
if e != nil {
println(e.Error())
return
}
btcsig := &btc.Signature{HashType: 0x01}
btcsig.R.Set(r)
btcsig.S.Set(s)
ms.Signatures = append(ms.Signatures, btcsig)
tx.TxIn[i].ScriptSig = ms.Bytes()
}
// Now re-order the signatures as they shall be:
multisig_reorder(tx)
write_tx_file(tx)
}
// this function signs either a message or a raw hash
func sign_message() {
var hash []byte
var signkey *btc.PrivateAddr
signkey = address_to_key(*signaddr)
if signkey == nil {
println("You do not have a private key for", *signaddr)
return
}
if *signhash != "" {
hash, er := hex.DecodeString(*signhash)
if er != nil {
println("Incorrect content of -hash parameter")
println(er.Error())
return
} else if len(hash) > 0 {
txsig := new(btc.Signature)
txsig.HashType = 0x01
r, s, e := btc.EcdsaSign(signkey.Key, hash)
if e != nil {
println(e.Error())
return
}
txsig.R.Set(r)
txsig.S.Set(s)
fmt.Println("PublicKey:", hex.EncodeToString(signkey.BtcAddr.Pubkey))
fmt.Println(hex.EncodeToString(txsig.Bytes()))
return
}
}
var msg []byte
if *message == "" {
msg, _ = ioutil.ReadAll(os.Stdin)
} else {
msg = []byte(*message)
}
hash = make([]byte, 32)
if litecoin {
ltc.HashFromMessage(msg, hash)
} else {
btc.HashFromMessage(msg, hash)
}
btcsig := new(btc.Signature)
var sb [65]byte
sb[0] = 27
if signkey.IsCompressed() {
sb[0] += 4
}
r, s, e := btc.EcdsaSign(signkey.Key, hash)
if e != nil {
println(e.Error())
return
}
btcsig.R.Set(r)
btcsig.S.Set(s)
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(signkey.IsCompressed()), signkey.BtcAddr.Version)
if sa.Hash160 == signkey.BtcAddr.Hash160 {
fmt.Println(base64.StdEncoding.EncodeToString(sb[:]))
return
}
rpk = btcsig.RecoverPublicKey(hash[:], 1)
sa = btc.NewAddrFromPubkey(rpk.Bytes(signkey.IsCompressed()), signkey.BtcAddr.Version)
if sa.Hash160 == signkey.BtcAddr.Hash160 {
sb[0]++
fmt.Println(base64.StdEncoding.EncodeToString(sb[:]))
return
}
println("Something went wrong. The message has not been signed.")
}
// prepare a signed transaction
func sign_tx(tx *btc.Tx) (all_signed bool) {
var multisig_done bool
all_signed = true
// go through each input
for in := range tx.TxIn {
if ms, _ := btc.NewMultiSigFromScript(tx.TxIn[in].ScriptSig); ms != nil {
hash := tx.SignatureHash(ms.P2SH(), in, btc.SIGHASH_ALL)
for ki := range ms.PublicKeys {
k := public_to_key(ms.PublicKeys[ki])
if k != nil {
r, s, e := btc.EcdsaSign(k.Key, hash)
if e != nil {
println("ERROR in sign_tx:", e.Error())
all_signed = false
} else {
btcsig := &btc.Signature{HashType: 0x01}
btcsig.R.Set(r)
btcsig.S.Set(s)
ms.Signatures = append(ms.Signatures, btcsig)
tx.TxIn[in].ScriptSig = ms.Bytes()
multisig_done = true
}
}
}
} else {
uo := getUO(&tx.TxIn[in].Input)
if uo == nil {
println("ERROR: Unkown input:", tx.TxIn[in].Input.String(), "- missing balance folder?")
all_signed = false
continue
}
adr := addr_from_pkscr(uo.Pk_script)
if adr == nil {
fmt.Println("WARNING: Don't know how to sign input number", in)
fmt.Println(" Pk_script:", hex.EncodeToString(uo.Pk_script))
all_signed = false
continue
}
k := hash_to_key(adr.Hash160)
if k == nil {
fmt.Println("WARNING: You do not have key for", adr.String(), "at input", in)
all_signed = false
continue
}
er := tx.Sign(in, uo.Pk_script, btc.SIGHASH_ALL, k.BtcAddr.Pubkey, k.Key)
if er != nil {
fmt.Println("ERROR: Sign failed for input number", in, er.Error())
all_signed = false
}
}
}
// reorder signatures if we signed any multisig inputs
if multisig_done && !multisig_reorder(tx) {
all_signed = false
}
if !all_signed {
fmt.Println("WARNING: Not all the inputs have been signed")
}
return
}