基于GPU的大状态密码S盒差分性质评估方法  

Differential property evaluation method based on GPU for large-state cryptographic S-boxes

作　　者：张润莲[1] 张密 武小年[1] 舒瑞 ZHANG Runlian;ZHANG Mi;WU Xiaonian;SHU Rui(Guangxi Key Laboratory of Cryptography and Information Security(Guilin University of Electronic Technology),Guilin Guangxi 541004,China)

机构地区：[1]广西密码学与信息安全重点实验室(桂林电子科技大学),广西桂林541004

出　　处：《计算机应用》2024年第9期2785-2790,共6页journal of Computer Applications

基　　金：国家自然科学基金资助项目(62062026);广西重点研发计划项目(桂科AB23026131);广西创新研究团队项目(2019GXNSFGA245004)。

摘　　要：大状态的密码S盒能够为对称密码算法提供更好的混淆性,但对大状态S盒的性质评估开销巨大。为高效评估大状态密码S盒的差分性质,提出基于GPU并行计算的大状态密码S盒差分性质评估方法。该方法基于现有的差分均匀度计算方法,针对16比特S盒的差分均匀度和32比特S盒的差分性质,分别设计GPU并行方案,通过优化GPU并行粒度和负载均衡提高了核函数和GPU的执行效率,并缩短了计算时间。测试结果表明,相较于CPU方法和GPU并行方法,所提方法大幅降低了大状态S盒差分性质评估的计算时间,提高了对大状态S盒差分性质的评估效率:对16比特S盒差分均匀度的计算时间为0.3 min;对32比特S盒的单个输入差分的最大输出差分概率计算时间约5 min,对它的差分性质计算时间约2.6 h。Large-state cryptographic S-boxes can provide better obfuscation for symmetric encryption algorithms,but the costs for evaluating their properties are very expensive.To efficiently evaluate the differential properties of large-state cryptographic S-boxes,a GPU-based method for evaluating the differential properties of large-state cryptographic S-boxes was proposed.According to the existing differential uniformity calculation method,the GPU parallel schemes were designed for evaluating differential uniformity of 16-bit S-boxes and differential properties of 32-bit S-boxes respectively.The execution efficiencies of kernel functions and GPU were improved by the schemes,and the time costs were reduced by optimizing GPU parallel granularity and load balancing.The test results show that,compared with CPU methods and GPU parallel methods,the time costs of the proposed schemes for evaluating the differential properties of large-state cryptographic S-boxes are greatly reduced.The time for computing the differential uniformity of 16-bit S-box is 0.3 min;for a single input differential of 32-bit S-box,the time for computing the maximum output differential probability is about 5 min,and the time for evaluating the differential properties is about 2.6 h.

关 键 词：密码S盒 差分密码分析 差分均匀度 最大输出差分概率 GPU并行计算 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]