一种抗简单功耗分析攻击的模幂算法

在真实环境下对智能卡RSA算法进行了功耗采集，通过简单功耗分析攻击（SPA）提取出了密钥，证明了传统的模幂运算二元表示（BinaryRepresentation，BR）算法存在明显的密钥信息泄露缺陷。分析发现，信息泄露发生在程序的跳转分支处。针对这一缺陷，提出了一种原子化操作与引入随机数相结合的模幂算法。通过操作的原子化统一了模幂算法的执行路径，消除因跳转分支引起的信息泄露；引入随机数对密钥的汉明重量进行掩盖，有效地防止密钥信息的泄露。在MC8051上的实测验证表明，新算法确实具有抗简单功耗分析的特性。

A Countermeasure to Simple Power Analysis for Modular Exponentiation

The effect power of the running Smart card with RSA algorithm was collected to extract the Key by Simple Power Analysis Attaching （SPA）. That shows there existing obvious information leak defect of the traditional modular exponentiation Binary Representation. Information leak happened to the program branches from our research. A novel algorithm combining atomic operation with random number was presented to avoid prescribed problem. The operate path of modular exponentiation was unify and the Hamming Weight of the key was masked using random number with this algorithm so as not to exposure to the adventure of information leak. Experiments were done in MC8051. The results show that the algorithm is well resistance to SPA.