针对AES加密算法的时序驱动Cache攻击研究

Research on timing driven cache attack against AES encryption algorithm

时序驱动Cache攻击是指通过分析处理器中加密算法的不同执行时间来恢复密钥,从而实现对密码系统的攻击。文章针对AES加密算法进行时序驱动Cache攻击分析:首先介绍了Cache结构和信息泄露原理,指明对算法执行过程中泄露信息的利用,描述了AES算法,对基于碰撞的时序驱动Cache攻击和基于模板的时序驱动Cache攻击进行针对AES算法的攻击分析。需要特别指出的是,AES查表操作的实现方式是主流计算机硬件系统的固有特性,目前对这类攻击难以规避,且攻击可以应用于大多数的AES实现软件。

The purpose of cache-timing attacks is to recover the key by analyzing the different execution times of the encryption algorithm in the processor,so as to realize the attack on the cryptographic system.This paper analyzes cache-timing attacks on AES encryption algorithm.Firstly,the structure of cache and the principle of information leakage are introduced.At the same time,the utilization of leaked information in the process of algorithm execution is pointed out.Then the AES algorithm is described.Finally,cache-timing attacks based on collision and template are analyzed.It should be pointed out that the implementation of AES table lookup operation is an inherent characteristic of mainstream computer hardware system.It is difficult to evade this kind of attack at present.At the same time,this kind of attack can be applied to most AES implementation software.