minterjs-util/dist/cjs/public.js

Utils for Minter

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.isValidPublic = isValidPublic;
exports.publicToAddress = publicToAddress;
exports.publicToString = publicToString;
var _secp256k = require("secp256k1");
var _keccak = require("ethereum-cryptography/keccak");
var _assert = _interopRequireDefault(require("assert"));
var _prefix = require("./prefix.js");
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { "default": obj }; }
/**
 * Returns the ethereum address of a given public key.
 * Accepts "Ethereum public keys" and SEC1 encoded keys.
 * @param {Buffer|Uint8Array} publicKey
 * @return {Buffer}
 */
function publicToAddress(publicKey) {
  publicKey = (0, _prefix.toBuffer)(publicKey);
  if (publicKey.length === 32) {
    throw new Error('Mp... public can\'t be converted to address because first byte is dropped');
  }
  if (publicKey.length === 33) {
    // compressed to uncompressed
    publicKey = Buffer.from((0, _secp256k.publicKeyConvert)(publicKey, false)).slice(1);
  }
  if (publicKey.length === 65) {
    // uncompressed to Ethereum
    publicKey = publicKey.slice(1);
  }
  (0, _assert["default"])(publicKey.length === 64);
  // Only take the lower 160bits of the hash
  return (0, _keccak.keccak256)(publicKey).slice(-20);
}

/**
 * Return Minter style public key string
 * @param {Buffer|Uint8Array|string} publicKey
 * @return {string}
 */
function publicToString(publicKey) {
  publicKey = (0, _prefix.toBuffer)(publicKey);
  if (!Buffer.isBuffer(publicKey)) {
    throw new TypeError('Public key should be of type Buffer');
  }
  if (publicKey.length === 64) {
    // Ethereum style to uncompressed
    publicKey = Buffer.concat([Buffer.from([4]), publicKey]);
  }
  if (publicKey.length === 65) {
    // uncompressed to compressed
    publicKey = Buffer.from((0, _secp256k.publicKeyConvert)(publicKey, true));
  }
  if (publicKey.length === 33) {
    publicKey = publicKey.slice(1);
  }
  (0, _assert["default"])(publicKey.length === 32);
  return "Mp".concat(publicKey.toString('hex'));
}

/**
 * Checks if the public key satisfies the rules of the curve secp256k1
 * and the requirements of Minter.
 * @param {string|Buffer} publicKey - Compressed key without first byte, starts with `Mp` if is string
 * @return {boolean}
 */
function isValidPublic(publicKey) {
  if (typeof publicKey === 'string') {
    if (!(0, _prefix.isValidPublicKeyString)(publicKey)) {
      return false;
    }
    publicKey = (0, _prefix.mToBuffer)(publicKey);
  }
  if (publicKey.length !== 32) {
    return false;
  }
  // convert Minter to compressed: add first byte
  var compressed = Buffer.concat([Buffer.from([3]), publicKey]);
  return (0, _secp256k.publicKeyVerify)(compressed);
}