一种基于寄存器翻转时刻随机化的抗DPA攻击技术  

A DPA Resistant Technology Based on Register Switching Time Randomization

作　　者：乐大珩[1] 齐树波[1] 李少青[1] 张民选[1] 

机构地区：[1]国防科学技术大学计算机学院,长沙410073

出　　处：《计算机研究与发展》2012年第3期491-498,共8页Journal of Computer Research and Development

基　　金：国家"八六三"高技术研究发展计划基金项目(2009AA01Z124);国家自然科学基金项目(60873016)

摘　　要：在密码算法电路中寄存器翻转时刻随机化对芯片抗DPA(differential power analysis)攻击能力有很大影响,因此提出了一种基于寄存器翻转时刻随机化的抗DPA攻击技术,其核心是利用不同频率时钟相位差的变化实现电路中关键寄存器翻转时刻的随机变化.针对跨时钟域的数据和控制信号,提出了需要满足的时序约束条件的计算方法,同时还分析了不同时钟频率对寄存器翻转时刻随机化程度的影响.以AES密码算法协处理器为例,实现了所提出的寄存器翻转时刻随机化技术,通过实验模拟的方法验证了理论分析的正确性.实验结果显示,在合理选择电路工作时钟频率的情况下,所提出的技术能够有效提高密码算法电路的抗DPA攻击性能.Completely automated public turing test to tell computers and humans apart（CAPTCHA）,also known as human interactive proof（HIP）,is a program that can generate and grade tests that most humans can pass and current computer programs cannot.CAPTCHA provides a way for automatically distinguishing a human from a computer program.It has emerged as a standard network security technology and has been successfully used in many popular Web sites,such as Google,Yahoo!,and Microsoft.CAPTCHA is designed based on certain unsolved artificial intelligence（AI） puzzles and can be categorized into three main types,namely,text-based,image-based,and sound-based,according to its carrier and concept.Text-based CAPTCHA based on character recognition has been widely used.Image-based CAPTCHA that exploits harder problems in computer vision is still in the research stage.Sound-based CAPTCHA,which is aimed at providing access to the visually impaired,is a complement to visual CAPTCHAs.This paper introduces the history and the general principle of CAPTCHA.The latest research progress in the design of CAPTCHA is expounded by enumerating typical examples.Their usability and security are also discussed.Finally,the directions for future study as well as the problems to be solved are pointed out.

关 键 词：差分功耗攻击 高级加密标准 防护技术 随机化 多时钟域 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]