数据加密标准的相关电磁分析

Research on Correlation Electromagnetic Analysis for DES

分析了CMOS逻辑门电路在运行时的电流特征,阐明了集成电路中数据与电磁辐射的相关性,建立了寄存器级电磁信息泄漏汉明距离模型。通过针对P89C668单片机实现的DES密码系统的攻击实验,介绍了相关电磁分析(Correlation Electromagnetic Analysis,CEMA)算法的设计与实现,分析了攻击点D的选择和计算方法,成功获得了DES第16轮48位子密钥,验证了电磁信息泄漏汉明距离模型。实验结果表明,工作状态下的CMOS集成电路存在电磁信息泄漏现象,相关分析比差分攻击更有效,DES每一轮的异或操作可以成为攻击点,为密码系统实施相关防护措施提供了依据。

The article analyzed the CMOS logical gate＇s electric current characteristic under the active status,explained data and electromagnetic emissions correlation of ICs, established the electromagnetic information leakage hamming distance model in registers level. Aimed at the data encryption standard （DES） cryptographic system realized by the P89C668 microcomputer, correlation electromagnetic analysis （CEMA） algorithm was described, the choice of attack point D and the computational method were analyzed, an attack experiment was processed by CEMA, thereby which made us obtain 48-bit sub-key of the 16th round of DES. The result shows that EM information leakage exists in CMOS integrated circuit during work, XOR operation in each round of DES is an attack point. The correlation analysis is more effective than the differential attack. It can provide a basis for implementing protective measures in the cryptographic systems.