I'm trying to sign a Psbt transaction from bitcoinjs-lib following what I found here:
I've checked that the compressed publicKey both from ledger, and the one from bitcoinjsLib returned the same value.
I could sign it with the bitcoinjs-lib ECPair, but when I tries to sign it using ledger, it is always invalid.
Can someone helps me point out where did I made a mistake?
These variables is already mentioned in the code below, but for clarity purpose:
- mnemonics:
abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about
- previousTx:
02000000000101869362410c61a69ab9390b2167d08219662196e869626e8b0350f1a8e4075efb0100000017160014ef3fdddccdb6b53e6dd1f5a97299a6ba2e1c11c3ffffffff0240420f000000000017a914f748afee815f78f97672be5a9840056d8ed77f4887df9de6050000000017a9142ff4aa6ffa987335c7bdba58ef4cbfecbe9e49938702473044022061a01bf0fbac4650a9b3d035b3d9282255a5c6040aa1d04fd9b6b52ed9f4d20a022064e8e2739ef532e6b2cb461321dd20f5a5d63cf34da3056c428475d42c9aff870121025fb5240daab4cee5fa097eef475f3f2e004f7be702c421b6607d8afea1affa9b00000000
- paths:
["0'/0/0"]
- redeemScript: (non-multisig segwit)
00144328adace54072cd069abf108f97cf80420b212b
This is my minimum reproducible code I've got.
/* tslint:disable */
// @ts-check
require('regenerator-runtime');
const bip39 = require('bip39');
const { default: Transport } = require('@ledgerhq/hw-transport-node-hid');
const { default: AppBtc } = require('@ledgerhq/hw-app-btc');
const bitcoin = require('bitcoinjs-lib');
const mnemonics = 'abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about';
const NETWORK = bitcoin.networks.regtest;
/**
* @param {string} pk
* @returns {string}
*/
function compressPublicKey(pk) {
const { publicKey } = bitcoin.ECPair.fromPublicKey(Buffer.from(pk, 'hex'));
return publicKey.toString('hex');
}
/** @returns {Promise<any>} */
async function appBtc() {
const transport = await Transport.create();
const btc = new AppBtc(transport);
return btc;
}
const signTransaction = async() => {
const ledger = await appBtc();
const paths = ["0'/0/0"];
const [ path ] = paths;
const previousTx = "02000000000101869362410c61a69ab9390b2167d08219662196e869626e8b0350f1a8e4075efb0100000017160014ef3fdddccdb6b53e6dd1f5a97299a6ba2e1c11c3ffffffff0240420f000000000017a914f748afee815f78f97672be5a9840056d8ed77f4887df9de6050000000017a9142ff4aa6ffa987335c7bdba58ef4cbfecbe9e49938702473044022061a01bf0fbac4650a9b3d035b3d9282255a5c6040aa1d04fd9b6b52ed9f4d20a022064e8e2739ef532e6b2cb461321dd20f5a5d63cf34da3056c428475d42c9aff870121025fb5240daab4cee5fa097eef475f3f2e004f7be702c421b6607d8afea1affa9b00000000"
const utxo = bitcoin.Transaction.fromHex(previousTx);
const segwit = utxo.hasWitnesses();
const txIndex = 0;
// ecpairs things.
const seed = await bip39.mnemonicToSeed(mnemonics);
const node = bitcoin.bip32.fromSeed(seed, NETWORK);
const ecPrivate = node.derivePath(path);
const ecPublic = bitcoin.ECPair.fromPublicKey(ecPrivate.publicKey, { network: NETWORK });
const p2wpkh = bitcoin.payments.p2wpkh({ pubkey: ecPublic.publicKey, network: NETWORK });
const p2sh = bitcoin.payments.p2sh({ redeem: p2wpkh, network: NETWORK });
const redeemScript = p2sh.redeem.output;
const fromLedger = await ledger.getWalletPublicKey(path, { format: 'p2sh' });
const ledgerPublicKey = compressPublicKey(fromLedger.publicKey);
const bitcoinJsPublicKey = ecPublic.publicKey.toString('hex');
console.log({ ledgerPublicKey, bitcoinJsPublicKey, address: p2sh.address, segwit, fromLedger, redeemScript: redeemScript.toString('hex') });
var tx1 = ledger.splitTransaction(previousTx, true);
const psbt = new bitcoin.Psbt({ network: NETWORK });
psbt.addInput({
hash: utxo.getId(),
index: txIndex,
nonWitnessUtxo: Buffer.from(previousTx, 'hex'),
redeemScript,
});
psbt.addOutput({
address: 'mgWUuj1J1N882jmqFxtDepEC73Rr22E9GU',
value: 5000,
});
psbt.setMaximumFeeRate(1000 * 1000 * 1000); // ignore maxFeeRate we're testnet anyway.
psbt.setVersion(2);
/** @type {string} */
// @ts-ignore
const newTx = psbt.__CACHE.__TX.toHex();
console.log({ newTx });
const splitNewTx = await ledger.splitTransaction(newTx, true);
const outputScriptHex = await ledger.serializeTransactionOutputs(splitNewTx).toString("hex");
const expectedOutscriptHex = '0188130000000000001976a9140ae1441568d0d293764a347b191025c51556cecd88ac';
// stolen from: https://github.com/LedgerHQ/ledgerjs/blob/master/packages/hw-app-btc/tests/Btc.test.js
console.log({ outputScriptHex, expectedOutscriptHex, eq: expectedOutscriptHex === outputScriptHex });
const inputs = [ [tx1, 0, p2sh.redeem.output.toString('hex') /** ??? */] ];
const ledgerSignatures = await ledger.signP2SHTransaction(
inputs,
paths,
outputScriptHex,
0, // lockTime,
undefined, // sigHashType = SIGHASH_ALL ???
utxo.hasWitnesses(),
2, // version??,
);
const signer = {
network: NETWORK,
publicKey: ecPrivate.publicKey,
/** @param {Buffer} $hash */
sign: ($hash) => {
const expectedSignature = ecPrivate.sign($hash); // just for comparison.
const [ ledgerSignature0 ] = ledgerSignatures;
const decodedLedgerSignature = bitcoin.script.signature.decode(Buffer.from(ledgerSignature0, 'hex'));
console.log({
$hash: $hash.toString('hex'),
expectedSignature: expectedSignature.toString('hex'),
actualSignature: decodedLedgerSignature.signature.toString('hex'),
});
// return signature;
return decodedLedgerSignature.signature;
},
};
psbt.signInput(0, signer);
const validated = psbt.validateSignaturesOfInput(0);
psbt.finalizeAllInputs();
const hex = psbt.extractTransaction().toHex();
console.log({ validated, hex });
};
if (process.argv[1] === __filename) {
signTransaction().catch(console.error)
}
Ooof, finally got it working.
My mistake was I was trying to sign a p2sh-p2ms, By following a reference on how to sign a p2sh-p2wsh-p2ms.
And, also, that missing last 2 bit (01), which I think represent SIGHASH_ALL caused an error when I try to decode the signature.
this is my finalized working example.
// @ts-check
require('regenerator-runtime');
const bip39 = require('bip39');
const { default: Transport } = require('@ledgerhq/hw-transport-node-hid');
const { default: AppBtc } = require('@ledgerhq/hw-app-btc');
const serializer = require('@ledgerhq/hw-app-btc/lib/serializeTransaction');
const bitcoin = require('bitcoinjs-lib');
const mnemonics = 'abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about';
const NETWORK = bitcoin.networks.regtest;
const DEFAULT_LOCK_TIME = 0;
const SIGHASH_ALL = 1;
const PATHS = ["m/49'/1'/0'/0/0", "m/49'/1'/0'/0/1"];
async function appBtc() {
const transport = await Transport.create();
const btc = new AppBtc(transport);
return btc;
}
/**
* @param {string} pk
* @returns {string}
*/
function compressPublicKey(pk) {
const {
publicKey
} = bitcoin.ECPair.fromPublicKey(Buffer.from(pk, 'hex'));
return publicKey.toString('hex');
}
/**
* @param {AppBtc} ledger
* @param {bitcoin.Transaction} tx
*/
function splitTransaction(ledger, tx) {
return ledger.splitTransaction(tx.toHex(), tx.hasWitnesses());
}
const signTransaction = async() => {
const seed = await bip39.mnemonicToSeed(mnemonics);
const node = bitcoin.bip32.fromSeed(seed, NETWORK);
const signers = PATHS.map((p) => node.derivePath(p));
const publicKeys = signers.map((s) => s.publicKey);
const p2ms = bitcoin.payments.p2ms({ pubkeys: publicKeys, network: NETWORK, m: 1 });
const p2shP2ms = bitcoin.payments.p2sh({ redeem: p2ms, network: NETWORK });
const previousTx = '02000000000101588e8fc89afea9adb79de2650f0cdba762f7d0880c29a1f20e7b468f97da9f850100000017160014345766130a8f8e83aef8621122ca14fff88e6d51ffffffff0240420f000000000017a914a0546d83e5f8876045d7025a230d87bf69db893287df9de6050000000017a9142ff4aa6ffa987335c7bdba58ef4cbfecbe9e49938702483045022100c654271a891af98e46ca4d82ede8cccb0503a430e50745f959274294c98030750220331b455fed13ff4286f6db699eca06aa0c1c37c45c9f3aed3a77a3b0187ff4ac0121037ebcf3cf122678b9dc89b339017c5b76bee9fedd068c7401f4a8eb1d7e841c3a00000000';
const utxo = bitcoin.Transaction.fromHex(previousTx);
const txIndex = 0;
const destination = p2shP2ms;
const redeemScript = destination.redeem.output;
// const witnessScript = destination.redeem.redeem.output;
const ledgerRedeemScript = redeemScript;
// use witness script if the outgoing transaction was from a p2sh-p2wsh-p2ms instead of p2sh-p2ms
const fee = 1000;
/** @type {number} */
// @ts-ignore
const amount = utxo.outs[txIndex].value;
const withdrawAmount = amount - fee;
const psbt = new bitcoin.Psbt({ network: NETWORK });
const version = 1;
psbt.addInput({
hash: utxo.getId(),
index: txIndex,
nonWitnessUtxo: utxo.toBuffer(),
redeemScript,
});
psbt.addOutput({
address: '2MsK2NdiVEPCjBMFWbjFvQ39mxWPMopp5vp',
value: withdrawAmount
});
psbt.setVersion(version);
/** @type {bitcoin.Transaction} */
// @ts-ignore
const newTx = psbt.__CACHE.__TX;
const ledger = await appBtc();
const inLedgerTx = splitTransaction(ledger, utxo);
const outLedgerTx = splitTransaction(ledger, newTx);
const outputScriptHex = await serializer.serializeTransactionOutputs(outLedgerTx).toString('hex');
/** @param {string} path */
const signer = (path) => {
const ecPrivate = node.derivePath(path);
// actually only publicKey is needed, albeit ledger give an uncompressed one.
// const { publicKey: uncompressedPublicKey } = await ledger.getWalletPublicKey(path);
// const publicKey = compressPublicKey(publicKey);
return {
network: NETWORK,
publicKey: ecPrivate.publicKey,
/** @param {Buffer} $hash */
sign: async ($hash) => {
const ledgerTxSignatures = await ledger.signP2SHTransaction({
inputs: [[inLedgerTx, txIndex, ledgerRedeemScript.toString('hex')]],
associatedKeysets: [ path ],
outputScriptHex,
lockTime: DEFAULT_LOCK_TIME,
segwit: newTx.hasWitnesses(),
transactionVersion: version,
sigHashType: SIGHASH_ALL,
});
const [ ledgerSignature ] = ledgerTxSignatures;
const expectedSignature = ecPrivate.sign($hash);
const finalSignature = (() => {
if (newTx.hasWitnesses()) {
return Buffer.from(ledgerSignature, 'hex');
};
return Buffer.concat([
ledgerSignature,
Buffer.from('01', 'hex'), // SIGHASH_ALL
]);
})();
console.log({
expectedSignature: expectedSignature.toString('hex'),
finalSignature: finalSignature.toString('hex'),
});
const { signature } = bitcoin.script.signature.decode(finalSignature);
return signature;
},
};
}
await psbt.signInputAsync(0, signer(PATHS[0]));
const validate = await psbt.validateSignaturesOfAllInputs();
await psbt.finalizeAllInputs();
const hex = psbt.extractTransaction().toHex();
console.log({ validate, hex });
};
if (process.argv[1] === __filename) {
signTransaction().catch(console.error)
}