// signMsgTx sets the SignatureScript for every item in msgtx.TxIn.
// It must be called every time a msgtx is changed.
// Only P2PKH outputs are supported at this point.
func signMsgTx(msgtx *wire.MsgTx, prevOutputs []wtxmgr.Credit, mgr *waddrmgr.Manager, chainParams *chaincfg.Params) error {
if len(prevOutputs) != len(msgtx.TxIn) {
return fmt.Errorf(
"Number of prevOutputs (%d) does not match number of tx inputs (%d)",
len(prevOutputs), len(msgtx.TxIn))
}
for i, output := range prevOutputs {
// Errors don't matter here, as we only consider the
// case where len(addrs) == 1.
_, addrs, _, _ := txscript.ExtractPkScriptAddrs(output.PkScript,
chainParams)
if len(addrs) != 1 {
continue
}
apkh, ok := addrs[0].(*coinutil.AddressPubKeyHash)
if !ok {
return ErrUnsupportedTransactionType
}
ai, err := mgr.Address(apkh)
if err != nil {
return fmt.Errorf("cannot get address info: %v", err)
}
pka := ai.(waddrmgr.ManagedPubKeyAddress)
privkey, err := pka.PrivKey()
if err != nil {
return fmt.Errorf("cannot get private key: %v", err)
}
sigscript, err := txscript.SignatureScript(msgtx, i,
output.PkScript, txscript.SigHashAll, privkey,
ai.Compressed())
if err != nil {
return fmt.Errorf("cannot create sigscript: %s", err)
}
msgtx.TxIn[i].SignatureScript = sigscript
}
return nil
}
// Test the sigscript generation for valid and invalid inputs, all
// hashTypes, and with and without compression. This test creates
// sigscripts to spend fake coinbase inputs, as sigscripts cannot be
// created for the MsgTxs in txTests, since they come from the blockchain
// and we don't have the private keys.
func TestSignatureScript(t *testing.T) {
t.Parallel()
privKey, _ := btcec.PrivKeyFromBytes(btcec.S256(), privKeyD)
nexttest:
for i := range sigScriptTests {
tx := wire.NewMsgTx()
output := wire.NewTxOut(500, []byte{txscript.OP_RETURN})
tx.AddTxOut(output)
for _ = range sigScriptTests[i].inputs {
txin := wire.NewTxIn(coinbaseOutPoint, nil)
tx.AddTxIn(txin)
}
var script []byte
var err error
for j := range tx.TxIn {
var idx int
if sigScriptTests[i].inputs[j].indexOutOfRange {
t.Errorf("at test %v", sigScriptTests[i].name)
idx = len(sigScriptTests[i].inputs)
} else {
idx = j
}
script, err = txscript.SignatureScript(tx, idx,
sigScriptTests[i].inputs[j].txout.PkScript,
sigScriptTests[i].hashType, privKey,
sigScriptTests[i].compress)
if (err == nil) != sigScriptTests[i].inputs[j].sigscriptGenerates {
if err == nil {
t.Errorf("passed test '%v' incorrectly",
sigScriptTests[i].name)
} else {
t.Errorf("failed test '%v': %v",
sigScriptTests[i].name, err)
}
continue nexttest
}
if !sigScriptTests[i].inputs[j].sigscriptGenerates {
// done with this test
continue nexttest
}
tx.TxIn[j].SignatureScript = script
}
// If testing using a correct sigscript but for an incorrect
// index, use last input script for first input. Requires > 0
// inputs for test.
if sigScriptTests[i].scriptAtWrongIndex {
tx.TxIn[0].SignatureScript = script
sigScriptTests[i].inputs[0].inputValidates = false
}
// Validate tx input scripts
scriptFlags := txscript.ScriptBip16 | txscript.ScriptVerifyDERSignatures
for j := range tx.TxIn {
vm, err := txscript.NewEngine(sigScriptTests[i].
inputs[j].txout.PkScript, tx, j, scriptFlags, nil)
if err != nil {
t.Errorf("cannot create script vm for test %v: %v",
sigScriptTests[i].name, err)
continue nexttest
}
err = vm.Execute()
if (err == nil) != sigScriptTests[i].inputs[j].inputValidates {
if err == nil {
t.Errorf("passed test '%v' validation incorrectly: %v",
sigScriptTests[i].name, err)
} else {
t.Errorf("failed test '%v' validation: %v",
sigScriptTests[i].name, err)
}
continue nexttest
}
}
}
}