一种基于混沌变换的多变量密码体制

Multivariate cryptosystem based on chaos

多变量公钥密码体制变换过程均为矩阵运算,导致其安全性存在缺陷,针对此问题,文章提出基于混沌映射的多变量密码体制。利用混沌映射的非线性、伪随机性等特性,对明文进行混沌预处理,同时摒弃传统多变量公钥密码体制中的第1个仿射变换,将多变量密码体制内部的线性变换转换为非线性变换,再通过中心映射和另一个仿射变换进行混淆与扩散处理。安全性分析显示,新的多变量密码体制能够有效抵抗各种常见的攻击,可以应用于加解密与签名。

The matrix operations in multivariate public key cryptosystem lead to security threats.To improve the security of multivariate cryptosystem,a novel multivariate cryptosystem with a chaos perturbation is proposed.Based on the nonlinearity and pseudo-random features,plaintexts are pre-processed by using a chaos system.At the same time,one of affine transformations in the traditional multivariate cryptosystem is discarded and the linear transformation inside the multivariate cryptosystem is transferred into nonlinear transformation.The diffusion and confusion operations are applied by the central map and the other transformation in multivariate cryptosystem.The result of security analysis indicates that the proposed cryptosystem resists common attacks and is an alternative cryptosystem for encryption and signature.