bip38-decrypt/lib/bip38-decrypt.js

Decrypt and Verify a Bip38 Encrypted Private Key

var CoinKey = require('coinkey')
var Bip38 = require('bip38')
var bip38 = new Bip38
var cs = require('coinstring')
var hash = require('crypto-hashing')

module.exports = function (encryptedPrivKey, password, cb) {
  
  try {
    var decrypedPrivKey = bip38.decrypt(encryptedPrivKey,password)
    var decryptedAddress = new CoinKey.fromWif(decrypedPrivKey).publicAddress
    var checksum = hash.sha256(hash.sha256(decryptedAddress))
    var hex = cs.decode(encryptedPrivKey)
  }
  catch(err) {
    return cb(err)
  }
  
  if (
      checksum[0] === hex[3] && 
      checksum[1] === hex[4] && 
      checksum[2] === hex[5] && 
      checksum[3] === hex[6]
     ) {
    return cb(null,decrypedPrivKey)
  }
  return cb(new Error("Wrong Password"))
}