module Encryption
  ENCRYPTION_KEY = [0x4A, 0x8F, 0x2C, 0xE1, 0x73, 0xB5, 0x96, 0x0D,
                    0x5E, 0xA2, 0x3F, 0xC7, 0x81, 0x14, 0x6B, 0xD9]

  def self.xor(data)
    data.bytes.each_with_index.map { |b, i| b ^ ENCRYPTION_KEY[i % ENCRYPTION_KEY.length] }.pack("C*")
  end
end