摘要
详细阐述了算法中s盒的结构，给出了用其C语言实现的程序代码。 s盒由有限域gf(28 )上所有元素的乘法逆元和域gf )上的仿射变换组成，经过s盒的非线性字节置换，使密文的差分均匀性和线性偏差达到理想状态，提高了A E S算法对差分密码分析和线性密码分析的抵抗力。 n个循环的加密过程都是对状态矩阵中的字节求有限域GF[28]上的乘法逆元和GF[2]上的仿射变换，但由于它们需要多次进行运算量大的非线性字节变换操作，所以用一定的算法首先求出GF[28]
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