摘要： 功耗分析能够有效地析出内嵌密码芯片的分组密码的密钥，Walsh谱变换是一种研究分组密码布尔函数的重要工具。该文在相关功耗分析的基础上，提出了一种基于Walsh谱的功耗分析新方法，证明了分组密码布尔函数的非线性度越高，密码防范功耗分析的能力就越弱的结论。实验表明，相对差分功耗分析、相关功耗分析而言，基于Walsh谱的功耗分析能有效地提高析出密钥的效率和精度。

关键词: 分组密码, 相关功耗分析, 高级加密标准, Walsh谱, 非线性度

Abstract:

Block cipher cryptosystems embedded in cryptographic devices are sensitive to a series of cryptanalysis such as power analysis. The Walsh spectrum is an important basis for studying the Boolean functions in block cipher. This paper proposes a new method based on Walsh spectrum to reveal the key embedded in cryptographic. Furthermore, conclusion are drawn and proved that the vulnerability against power analysis caused by the highly nonlinear S-boxes. Experimental results indicate that the new method speeds up the revelation of key and yields higher precision.

Key words: block cipher, correlation power analysis, AES, Walsh spectrum, nonlinearity

中图分类号: 

• TP309.7