基于流密码代数攻击的研究

A Study of the Algebraic Attacks on Stream Ciphers

概述了流密码代数攻击的提出和发展,介绍了它的基本思想。简要描述了代数攻击的一般算法和可攻击的流密码类型,针对带记忆和不带记忆非线性组合流密码的代数攻击,阐述了Courtois等人的具体工作,并给出了两个新的选择非线性布尔函数的标准。笔者提出了密码非线性部分未知情况下的一般代数攻击方法,最后总结了代数攻击的贡献和不足之处。

In this paper,the basic contents of the algebraic attacks on stream ciphers with linear feedback are introduced. A simple description is given to the general arithmetic of algebraic attacks and the type of stream ciphers that can be attacked,The rule discovered by Courtois at algebraic attacks on stream ciphers with (and without) memory is presented,and two new criterion on selecting good Boolean function are presented. A general algebraic attacks on ciphers which the nonlinear combiner unknown is put forward by writer,The contribution and shortage of algebraic attacks are summarized.