Crypton算法的不可能差分分析

发布时间：2018-09-09 10:49

【摘要】：Crypton算法是基于Square算法设计的SPN结构类密码算法,由于其具备良好的软硬件性能而引起了广泛的关注.对Crypton分组密码算法在不可能差分分析下的安全性进行了研究.通过分析Crypton算法扩散层的性质,指出了现有7轮Crypton算法不可能差分分析中存在的问题,结合快速排序、分割攻击与早夭技术对7轮Crypton算法的不可能差分分析进行了改进,降低了其数据复杂度与时间复杂度;同时,通过并行使用4条不可能差分区分器,结合密钥扩展算法的性质给出了7轮Crypton算法的多重不可能差分分析结果,恢复了算法的主密钥;最后,在7轮Crypton算法的不可能差分分析的基础上向后拓展1轮,给出了8轮Crypton-256算法的不可能差分分析,恢复了其主密钥,其数据复杂度为2103个选择明文,时间复杂度为2~(214)次8轮Crypton加密,存储复杂度为2~(154.4)B.研究结果表明:结合算法的性质及多种技术给出了Crypton算法目前最优的不可能差分分析结果.
[Abstract]:Crypton algorithm is a kind of cryptographic algorithm of SPN structure designed based on Square algorithm. Because of its good performance of software and hardware, Crypton algorithm has attracted wide attention. The security of Crypton block cipher algorithm under impossible differential analysis is studied. By analyzing the properties of the diffusion layer of the Crypton algorithm, the paper points out the problems existing in the existing 7 rounds Crypton algorithm in the impossible differential analysis, and improves the 7 round Crypton algorithm by combining the quick sorting, segmentation attack and early death techniques. The data complexity and time complexity are reduced, and the multi-impossibility difference analysis results of seven rounds of Crypton algorithm are given by using four impossibility differentiators in parallel and combining the properties of the key extension algorithm. The main key of the algorithm is restored. Finally, on the basis of 7 rounds of impossibility difference analysis of Crypton algorithm, we extend the first round backward, and give 8 rounds of impossible difference analysis of Crypton-256 algorithm, and restore its master key. Its data complexity is 2103 selectable plaintext. The time complexity is 2 ~ (214) times 8 rounds of Crypton encryption and the storage complexity is 2 ~ (154.4) B. The results show that: combining with the properties of the algorithm and various techniques, the results of the Crypton algorithm are given the most optimal difference analysis at present.
【作者单位】：解放军信息工程大学;
【基金】：中国博士后科学基金项目(2014M562582)~~
【分类号】：TN918.1

【参考文献】