liquidjs-lib/src/psetv2/bip32.js

Client-side Liquid JavaScript library

'use strict';
Object.defineProperty(exports, '__esModule', { value: true });
exports.encodeBIP32Derivation =
  exports.decodeBip32Derivation =
  exports.hardenedKeyStart =
    void 0;
exports.hardenedKeyStart = 0x80000000;
function decodeBip32Derivation(buf) {
  if (buf.length % 4 !== 0 || buf.length / 4 - 1 < 1) {
    throw new Error('invalid BIP32 derivation format');
  }
  const masterFingerprint = buf.slice(0, 4);
  const steps = [];
  for (let i = 4; i < buf.length; i += 4) {
    steps.push(buf.slice(i, i + 4).readUInt32LE());
  }
  const path = stepsToString(steps);
  return { masterFingerprint, path };
}
exports.decodeBip32Derivation = decodeBip32Derivation;
function encodeBIP32Derivation(masterFingerprint, path) {
  const steps = path.split('/');
  const buf = Buffer.allocUnsafe(4 + 4 * steps.length);
  masterFingerprint.copy(buf, 0);
  let offset = 4;
  steps.forEach((step) => {
    const isHardened = step.slice(-1) === "'";
    let num = 0x7fffffff & parseInt(isHardened ? step.slice(0, -1) : step, 10);
    if (isHardened) num += exports.hardenedKeyStart;
    buf.writeUInt32LE(num, offset);
    offset += 4;
  });
  return buf;
}
exports.encodeBIP32Derivation = encodeBIP32Derivation;
function stepsToString(steps) {
  const stepsStr = steps.map((step) => stepToString(step));
  return stepsStr.join('/');
}
function stepToString(step) {
  if (step < exports.hardenedKeyStart) {
    return step.toString();
  }
  step -= exports.hardenedKeyStart;
  return step.toString() + "'";
}