研究成果

国際会議

  • Key-Dependent Weakness of AES-Based Ciphers Under Clockwise Collision Distinguisher
    著者
    T. Nakasone, Y. Li, Y. Sasaki, M. Iwamoto, K. Ohta, and K. Sakiyama
    会議名
    ICISC 2012
    LNCS 7839
    ページ
    395–409
    出版社
    Springer
    発行年
    2012
    発表日
    Dec., 2012
    Abstract

    In 2011, Li et al. proposed a series of side-channel attacks that are related to a fundamental side-channel leakage source called clockwise collision. This paper discloses the fact that hardware implementations of AES-based ciphers could have weak keys assuming that the leakage of clockwise collision is distinguishable. In order to explain this, we firstly set up an evaluation method by introducing a threshold-based distinguisher that takes an advantage of the locality of ElectroMagnetic (EM) measurements. Secondly, we discuss that the probability of clockwise collision depends on the key values and the byte positions in the AES states. Thirdly, based on practical EM measurements and mathematical analysis, we quantitatively evaluate the relationship between the probability of clockwise collision and the vulnerability to the side-channel attack. Finally, the discussion is extended to the design methodology of AES-based ciphers, i.e., the parameter selection for S-box and ShiftRows.