Release v0.1.0

vendor/github.com/muun/libwallet/V2.go

@@ -0,0 +1,106 @@
+package libwallet
+
+import (
+	"github.com/btcsuite/btcd/txscript"
+	"github.com/btcsuite/btcutil"
+	"github.com/pkg/errors"
+
+	"github.com/btcsuite/btcd/wire"
+)
+
+func CreateAddressV2(userKey, muunKey *HDPublicKey) (MuunAddress, error) {
+
+	script, err := createRedeemScriptV2(userKey, muunKey)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to generate redeem script v2")
+	}
+
+	address, err := btcutil.NewAddressScriptHash(script, userKey.Network.network)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to generate multisig address")
+	}
+
+	return &muunAddress{
+		address:        address.String(),
+		version:        addressV2,
+		derivationPath: userKey.Path,
+		redeemScript:   script,
+	}, nil
+}
+
+func createRedeemScriptV2(userKey, muunKey *HDPublicKey) ([]byte, error) {
+
+	userAddress, err := btcutil.NewAddressPubKey(userKey.Raw(), userKey.Network.network)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to generate address for user")
+	}
+
+	muunAddress, err := btcutil.NewAddressPubKey(muunKey.Raw(), muunKey.Network.network)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to generate address for muun")
+	}
+
+	return txscript.MultiSigScript([]*btcutil.AddressPubKey{
+		userAddress,
+		muunAddress,
+	}, 2)
+}
+
+func addUserSignatureInputV2(input Input, index int, tx *wire.MsgTx, privateKey *HDPrivateKey,
+	muunKey *HDPublicKey) (*wire.TxIn, error) {
+
+	if len(input.MuunSignature()) == 0 {
+		return nil, errors.Errorf("muun signature must be present")
+	}
+
+	txInput := tx.TxIn[index]
+
+	redeemScript, err := createRedeemScriptV2(privateKey.PublicKey(), muunKey)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to build reedem script for signing")
+	}
+
+	sig, err := signInputV2(input, index, tx, privateKey.PublicKey(), muunKey, privateKey)
+	if err != nil {
+		return nil, err
+	}
+
+	// This is a standard 2 of 2 multisig script
+	// 0 because of a bug in bitcoind
+	// Then the 2 sigs: first the users and then muuns
+	// Last, the script that contains the two pub keys and OP_CHECKMULTISIG
+	builder := txscript.NewScriptBuilder()
+	builder.AddInt64(0)
+	builder.AddData(sig)
+	builder.AddData(input.MuunSignature())
+	builder.AddData(redeemScript)
+	script, err := builder.Script()
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to generate signing script")
+	}
+
+	txInput.SignatureScript = script
+
+	return txInput, nil
+}
+
+func signInputV2(input Input, index int, tx *wire.MsgTx, userKey, muunKey *HDPublicKey,
+	signingKey *HDPrivateKey) ([]byte, error) {
+
+	redeemScript, err := createRedeemScriptV2(userKey, muunKey)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to build reedem script for signing")
+	}
+
+	privKey, err := signingKey.key.ECPrivKey()
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to produce EC priv key for signing")
+	}
+
+	sig, err := txscript.RawTxInSignature(tx, index, redeemScript, txscript.SigHashAll, privKey)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to sign V2 output")
+	}
+
+	return sig, nil
+}