向量k-正规函数滤波模型流密码猜测确定攻击

Research on guess and determine attack on stream cipher with k-normality class filter generator

猜测确定攻击是非线性滤波生成器的有效分析方法。滤波函数的代数性质是直接关系该模型抵抗猜测确定攻击能力的关键因素之一。正规性是密码函数的一个重要指标。文中分析了当滤波函数为k-(弱)正规函数时,使得滤波器猜测确定攻击采样次数明显减少,在攻击所需要的预计算复杂度和存储复杂度不变的情况下,降低攻击复杂度了2n-m-k。

Guess and determine attack is a very practical method among cryptanalysis methods for streamciphers. Algebraic properties of the filter function is directly related to the model of resistance to one ofthe key factors whatis an important criterion in designing cryptographic functions. Thispaperanalyzesthatwhen the filter functions belongs to k- （weak） normality function, the filter state guessing attack and itsapplication to filter generators with filter is significantly reduced. In some cases, this approach reducesattack complexity compared to 2n-m-k.