一般SPT模型的抗差分和线性攻击安全性研究

为安全高效地在序列密码设计中应用SP网络,研究了一般SPT模型的抗差分攻击和线性攻击的能力,其中,S和T表示2个不同的可实现压缩的混淆层,P代表扩散层。给出了P为最佳扩散层时SPT模型的最大差分概率上界,给出了P为最佳扩散层且S和T均平衡时的最大线性逼近优势和最大线性包优势的上界,从而部分解决了该模型的抗差分和线性攻击安全性评估问题。

Security against differential and linear cryptanalysis for general SPT models

To use SP network in stream ciphers safely and efficiently,the ability against differential and linear cryptana-lysis of SPT models was studied,where S and T denote two different layers for substitution,in which compression could be achieved,and P denotes the layer for permutation.The upper bound of the maximum differential probability was given when the branch number of P was optimal,and the upper bound of the maximum linear approximation probability and the maximum linear hull probability are given when the branch number of P was optimal and when S and T were balanced.As a consequence,the problem about evaluating the security against differential and linear cryptanalysis for general SPT models was resolved partially.