Paper 2017/1051

A Novel Use of Kernel Discriminant Analysis as a Higher-Order Side-Channel Distinguisher

Xinping Zhou, Carolyn Whitnall, Elisabeth Oswald, Degang Sun, and Zhu Wang

Abstract

Distinguishers play an important role in Side Channel Analysis (SCA), where real world leakage information is compared against hypothetical predictions in order to guess at the underlying secret key. However, the direct relationship between leakages and predictions can be disrupted by the mathematical combining of $d$ random values with each sensitive intermediate value of the cryptographic algorithm (a so-called ``$d$-th order masking scheme''). In the case of software implementations, as long as the masking has been correctly applied, the guessable intermediates will be independent of any one point in the trace, or indeed of any tuple of fewer than $d+1$ points. However, certain $d+1$-tuples of time points may jointly depend on the guessable intermediates. A typical approach to exploiting this data dependency is to pre-process the trace -- computing carefully chosen univariate functions of all possible $d+1$-tuples -- before applying the usual univariate distinguishers. This has a computational complexity which is exponential in the order $d$ of the masking scheme. In this paper, we propose a new distinguisher based on Kernel Discriminant Analysis (KDA) which directly exploits properties of the mask implementation without the need to exhaustively pre-process the traces, thereby distinguishing the correct key with lower complexity.

Metadata
Available format(s)
PDF
Category
Implementation
Publication info
Published elsewhere. 17th Smart Card Research and Advanced Application Conference (CARDIS 2017)
Contact author(s)
zhouxinping @ iie ac cn
History
2017-10-31: received
Short URL
https://ia.cr/2017/1051
License
Creative Commons Attribution
CC BY

BibTeX

@misc{cryptoeprint:2017/1051,
      author = {Xinping Zhou and Carolyn Whitnall and Elisabeth Oswald and Degang Sun and Zhu Wang},
      title = {A Novel Use of Kernel Discriminant Analysis as a Higher-Order Side-Channel Distinguisher},
      howpublished = {Cryptology ePrint Archive, Paper 2017/1051},
      year = {2017},
      note = {\url{https://eprint.iacr.org/2017/1051}},
      url = {https://eprint.iacr.org/2017/1051}
}
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