【摘要】 ARIA密码是2003年由韩国学者提出,并在2004年被选为韩国分组密码标准的新的分组密码算法.为了使用不可能差分方法对ARIA密码算法进行安全性分析,首先,根据ARIA密码的结构特征,构造一条4轮不可能差分路径,通过在不可能差分路径前面增加2轮、后面增加1轮的方式,对7轮ARIA密码算法进行不可能差分攻击.研究结果表明:7轮攻击共需要2119选择明文和大约2218次7轮加密运算.与已有结果相比较,该次攻击进一步降低了数据复杂度和时间复杂度.同时,在4轮不可能差分路径基础上,通过前面增加2轮、后面增加2轮的方式,首次提出了对ARIA密码算法的8轮不可能差分的新攻击.研究结果表明:8轮不可能差分攻击共需要2207选择明文和大约2346次8轮加密运算,已超过穷举搜索的攻击复杂度,故可认为在该路径下的8轮不可能差分攻击中ARIA密码算法是安全的.更多还原

【Abstract】 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,and it has relatively high security.ARIA was established as a Korean Standard block cipher algorithm by Korean Agency for Technology and Standards in 2004.Combining the features of ARIA algorithm,a new impossible differential attack on7-round ARIA is proposed by adding 2-round at the beginning and 1-round at the end.It is shown that this new impossible differential attack requires a data complexity of about 2119 chosen plaintexts and a time complexity of about 2218 7-round ARIA encryptions.Compared with the previous impossible differential attacks,this attack efficiently reduces the data complexity and time complexity.Similar to the attack of 7-round,a new impossible differential attack on 8-round ARIA is proposed first time by adding 2-round at the beginning and 2-round at the end.It is shown that this new impossible differential attack requires a data complexity of about 2207 chosen plaintexts and a time complexity of about 2346 8-round ARIA encryptions.It has exceeded the attack complexity of exhaustive search attack,so we can believe that ARIA cryptographic algorithm is safe in this path of 8-round impossible differential attack.更多还原