一种结合离散混沌映射和Feistel网络的分组加密算法

A Block Encryption Algorithm Combined with the Discrete Chaotic Map and Feistel Network

论文提出了一种新颖的结合一维离散混沌映射与Feistel网络结构的分组密码算法(CFCEA)。分组长度为 64 bit,密钥长度为128bit,并使用了一个128bit长的辅助密钥。在轮函数中用Logistic混沌映射和3个代数群算子进行混合运算,此外还特别设计了子密钥生成算法。对CFCEA的密码学特性进行了分析,结果表明该算法具有严格的雪崩效应,扩散性能和扰乱性能理想。并且算法在64bit分组长度下差分概率和线性概率的理论上界分别近似为2-52.92和2-49.206,具备抵抗一定强度的差分和线性密码分析的能力。

In this paper a novel block encryption algorithm, which is called CFCEA, is proposed by combining the one dimensional discrete chaotic map and Feistel network. The algorithm operates on 64bit plaintext blocks, and the master key is 128 bit long, and an auxiliary key with size of 128 bit is exploited. Within the round function, the logistic chaotic map and three algebraic group operations are mixed. Moreover, the subkeys schedule is specially designed for the consideration of the security. The cryptographic properties of the algorithm are analyzed, and the results indicate that this algorithm satisfies the strict avalanche criterion and as a result, the diffusion and confusion properties of the algorithm are very ideal. Furthermore, when the block length is 64bit, the approximately upper bound of differential probability and linear probability of CFCEA is 2^-52.92 and 2^-492.06, respectively. This shows that the algorithm can resist differential and linear cryptanalysis with some strength.