       last[j] ^= xorsum[j]
       j++
     i++
+
   return last.toString('hex')


  ###*
   * Hash data
   * @param  {buffer} buffer The data to hash.
   * @return {buffer}        The hashed data.
  ###
  encrypt: (buffer) ->
    binary = Crypto.createHmac(@mode, @key).update(buffer).digest('binary')


###*
 * PBKDF2
 * @param {string|buffer} password The password to derive a key from.
 * @param {string|buffer} salt The salt.
 * @param {number} [count=10000] Number of iterations.
 * @param {number} [length=512] The SHA algorithm to use.
 * @return {buffer} The derived key.
###
module.exports = (password, salt, count=10000, length=512) ->

