基于轨道扰动的混沌单向散列函数设计  

Design of chaotic one-way hash function based on orbit perturbation

作　　者：李佩玥[1,2] 古力[3] 隋永新[1] 杨怀江[1] 

机构地区：[1]中国科学院长春光学精密机械与物理研究所应用光学国家重点实验室,吉林长春130033 [2]中国科学院研究生院,北京100039 [3]南开大学信息技术科学学院,天津300071

出　　处：《光学精密工程》2010年第9期2101-2108,共8页Optics and Precision Engineering

基　　金：国家973重点基础研究发展规划项目(No.2007CB311201)

摘　　要：在分析针对数字混沌提出的伪随机扰动策略和变参数补偿策略的基础上,提出了基于轨道扰动的混沌单向散列函数设计方法。首先,将消息填充为64byte的整数倍,以提高短消息散列的安全性;然后,选取64byte的固定扰动向量,并将明文信息与固定扰动向量一起映射至数字混沌系统相空间的扰动空间;最后,将扰动空间内的元素输入至数字混沌系统进行多次混沌迭代,并在迭代结果中取出160bit作为最终散列值。该算法选用Logistic映射作为混沌映射,计算复杂度比高维混沌映射低,而轨道扰动的思想使得该算法比一般的低维混沌映射安全性更高。研究表明,该算法对初值极其敏感,且具有很好的混乱和扩散性质及较高的抗碰撞性。该算法采用256bit定点数运算,更易于软硬件实现。On the basis of analysis on the pseudo-random perturbation policy and Variable Parameter Compensation（VPCM）policy for digital chaotic system,a method to design the chaotic one-way hash function based on the orbit perturbation is proposed.In order to improve the security of short message hashing,the message is padded to be a multiple of 64byte.Then,the length fixed perturbation of 64 bytes length is chosen,and the perturbation together with the padded message are mapped to the perturbation space of digital chaotic system.Finally,the digital chaotic system is iterated multiple times by using the elements of the perturbation space as inputs,and a hash value with 160bit length is extracted from the results.The proposed algorithm uses the logistic mapping as the chaotic mapping,of which the computational complexity is lower than the one that has a reasonable high dimension.As the orbit perturbation is introduced the algorithm,its security is higher than that of common one.The results indicate that the algorithm is sensitive to the initial message comparatively and shows good confusion and diffusion properties.Moreover,the fix-point operations with 256bits are used in the proposed algorithm,and it is easy to be completed by software or hardware.

关 键 词：单向散列函数 混沌映射 轨道扰动 

分 类 号：TP391[自动化与计算机技术—计算机应用技术] TP311[自动化与计算机技术—计算机科学与技术]