ARIA密码是2003年由韩国学者提出的新的分组密码算法,该密码与AES的设计原理相类似,并在2004年被选为韩国的分组密码标准。该文根据ARIA密码的结构特征,提出ARIA密码的一种新的7轮不可能差分攻击路径,首次实现了对ARIA-192的不可能差分攻击,攻击的时间复杂度为2176.2。同时,利用扩散层的相关性质降低攻击ARIA-256的时间复杂度为2192.2。
ARIA cipher is a new block cipher proposed by some South Korean experts in 2003. The design principle of ARIA is similar to the AES. ARIA is established as a Korean Standard block cipher algorithm by Korean Agency for Technology and Standards. In this paper, a new impossible differential attack on 7 rounds of the ARIA cipher is presented. By this attack, 7-round ARIA-192 is breakable with a data complexity of about 2176.2 encryptions, while the previous best impossible differential attack on ARIA broke on 7-round ARIA-256. Then some characters on diffusion layer are used to reduce the complexity of the ARIA-256 to 2192.2 .