class Eth::Key::Decrypter

def check_macs
  mac1 = Util.keccak256(key[(key_length / 2), key_length] + ciphertext)
  mac2 = Util.hex_to_bin crypto_data["mac"]
  if mac1 != mac2
    raise DecrypterError, "Message Authentications Codes do not match!"
  end
end