基于均匀化混沌系统生成S盒的算法研究

该文给出了一个新的二次多项式混沌系统,并利用系统与Tent映射拓扑共轭的性质,给出了系统的概率密度函数,基于概率密度的形式,进一步设计了一个变换函数,实现了系统的均匀化。针对均匀化前后的混沌系统构造了S盒生成算法,对该算法产生的300个S盒进行差分概率(DP)和线性概率(LP)的统计分析,结果表明均匀化后混沌系统产生的S盒的DP和LP略优于均匀化前的值。     

Constructing Differentially 4 Uniform Permutations from Known Ones

Low differential uniformity functions provide good resistance to differential attacks. The AES （Advanced encryption standard） uses a differentially 4 uniform function （the inverse function） as its S-box. We give a further study of the inverse function in this paper. It is observed that after exchanging two values of a low differential uniformity function, its differential property still keeps good. Especially, for the inverse function over F2^n （n even）, various possible differential uniformities are completely determined after its two values are exchanged. As a consequence, we get some highly nonlinear permutations with differential uniformity 4 which are not CCZ-equivalent （Carlet Charpin-Zinoviev equivalent） to the inverse function on F2^n.     

低轮次DES体制的忠实性

对低轮次 DES体制的忠实性进行了分析。DES体制的所有构成要素中 ,S-盒起着十分关键的作用 ,我们先分析了 S-盒的性质 ,并利用所得到的性质 ,对 DES的忠实性进行了研究。证明了结果 :对于 5 6比特的全密钥而言 ,第一轮 DES不是忠实的 ,第二轮和第三轮的 DES是忠实的。     

公共数据库中可信记录的认证码的研究

在用户享有授权可自由添加记录的公共数据库中，数据良莠难分。为提高公共数据库的可信度，推广了敏感数据的完整性锁的概念，提出了一种对经由领域专家验证的可靠记录作标记的方法，且称所作标记为认证码。讨论了认证码的生成准则，并借助于MD5算法、DES密码算法中的S盒和RSA密码体制，设计了一个认证码的生成方案，最后还指出所生成的认证码能有效地抵抗伪造攻击和替伐攻击。     

Area, Delay, and Power Characteristics of Standard-Cell Implementations of the AES S-Box

Cryptographic substitution boxes (S-boxes) are an integral part of modern block ciphers like the Advanced Encryption Standard (AES). There exists a rich literature devoted to the efficient implementation of cryptographic S-boxes, wherein hardware designs for FPGAs and standard cells received particular attention. In this paper we present a comprehensive study of different standard-cell implementations of the AES S-box with respect to timing (i.e. critical path), silicon area, power consumption, and combinations of these cost metrics. We examine implementations which exploit the mathematical properties of the AES S-box, constructions based on hardware look-up tables, and dedicated low-power solutions. Our results show that the timing, area, and power properties of the different S-box realizations can vary by up to almost an order of magnitude. In terms of area and area-delay product, the best choice are implementations which calculate the S-box output. On the other hand, the hardware look-up solutions are characterized by the shortest critical path. The dedicated low-power implementations do not only reduce power consumption by a large degree, but they also show good timing properties and offer the best power-delay and power-area product, respectively.     

基于S盒优化的轻量级加密算法设计

分组密码一直是解决信息系统安全问题的常用加密方法。分组密码的典型代表数据加密标准DES（Data Encryption Standard）被广泛应用于软件加密和硬件加密,其中所体现的设计思想和设计原则依然值得研究和借鉴。S盒作为DES算法的一个关键环节,它的设计好坏直接影响DES的加密性能。通过对分组密码安全性设计的分析,立足于DES算法框架,提出了一种轻量级安全加密算法LEA（Light weight Encryption Algorithm）,通过增加位选逻辑陷阱来对S盒中的元素进行选取和重新优化设计,最后从S盒统计特性角度对其安全性进行分析。该算法能有效解决低成本系统的安全问题。     

基于可变S盒的分组密码算法及其在媒体网关中的应用

分组密码算法是信息安全领域中最为重要的加解密技术之一。与传统的分组密码不同，该算法具有可变的S盒和变化的循环加密结构，从而大大提高了抗差分攻击和线性攻击的能力。结合某媒体网关的设计项目，研究了该算法并详细探导了其设计方法。员后，测试了算法的实际性能。