密码系统差分电磁分析研究

Research on differential electromagnetic analysis for cryptographic systems

针对AT89C52和P89C668两种单片机实现的DES密码系统,采用差分电磁分析的方法对其进行了密码破译实验,成功获得了DES第16轮48位子密钥。分析了CMOS门电路中数据与电磁辐射的相关性,建立了寄存器电磁信息泄漏模型,比较了汉明重量模型和汉明距离模型的攻击效果。实验结果表明,CMOS集成电路在工作时存在着电磁信息泄漏,不同的指令在两种泄漏模型下具有不同的泄漏特征,为密码系统实施相关防护措施提供了依据。

According to the cryptographic system which is realized by AT89C52 and P89C668 microcomputers and encrypted with DES （data encryption standard）, the 48-bits sub-key of the round 16th of DES is detected by differential electromagnetic analysis （DEMA）. Data and electromagnetic emissions correlation of CMOS are analyzed, the compromising emanations model in registers level is established and effect of hamming distance model is compared with hamming weight model. The experimental results indicate that CMOS integrated circuits have compromising emanations. The instructions have different characteristic of compromising emanations for two kinds of models. The basis of protection for cryptographic system is provided.