GACTF之Checkin

require 'openssl'  require 'base64'def aes_dicrypt(key,dicrypted_string)  # 将密码使用base64解码    cipher = Base64.decode64(dicrypted_string)           # 创建AES加密对象    aes = OpenSSL::Cipher.new("AES-128-ECB")    # 设置解密  aes.decrypt  # 设置key  aes.key = key    # 解密数据    cipher = aes.update(cipher) << aes.final    # 返回数据  return cipherendkey = "Welcome_To_GACTF"cipher = "4KeC/Oj1McI4TDIM2c9Y6ahahc6uhpPbpSgPWktXFLM=n"flag = aes_dicrypt(key,cipher)printf("flag:%sn",flag)