Abstract: This paper analyzes the stochastic search attack to encryption of FAPKC3 under the linear transformation form of its function, and presents a searching algorithm RSS. As the obscurity and difficulty of nonlinear RaRb method for generating nonlinear finite automaton, and the limitation of most-often used nonlinear operator AND in FAPKC3, it describes a new construction based on a simple upper-triangle matrix method.

Key words: Finite Automaton Public Key Cryptosystem(FAPKC), cryptographic analysis, stochastic search, upper-triangle matrix method

摘要： 针对FAPKC3 的加密，在自动机方程的线性变换形式下分析了已知密文的随机搜索攻击，提出搜索算法RSS，对安全密钥的生成进行了相关讨论并给出了相应建议。鉴于传统的非线性RaRb方法较为复杂，以及通常选用的“向量与”形式的非线性算子的缺陷，基于一种更为简单的“上三角矩阵法”提出了非线性算子的新构造。

关键词: 有限自动机公钥密码, 密码分析, 随机搜索, 上三角矩阵法

CLC Number: 

• TP309