Filtered nonlinear cryptanalysis of reduced-round Serpent, and the Wrong-Key Randomization Hypothesis.

James McLaughlin; John A.  Clark

Paper 2013/089

Filtered nonlinear cryptanalysis of reduced-round Serpent, and the Wrong-Key Randomization Hypothesis.

James McLaughlin and John A. Clark

Abstract

We present a deterministic algorithm to find nonlinear S-box approximations, and a new nonlinear cryptanalytic technique; the “filtered” nonlinear attack, which achieves the lowest data complexity of any known-plaintext attack on reduced-round Serpent so far. We demonstrate that the Wrong-Key Randomization Hypothesis is not entirely valid for attacks on reduced-round Serpent which rely on linear cryptanalysis or a variant thereof, and survey the effects of this on existing attacks (including existing nonlinear attacks) on 11 and 12-round Serpent.

Metadata

Available format(s): PDF
Category: Secret-key cryptography
Publication info: Published elsewhere. Updated and expanded version of a paper submitted to ACISP 2013. Graphs of attack performance, and truncated differential bias tables for Serpent S2/S4^{-1} were not in the ACISP version; furthermore a memory optimisation and a more thorough analysis of the Nguyen/Wu/Wang multidimensional attack were added after the ACISP submission. Some of the material in this paper includes revisions of results from 2013/022 in light of the new work on the WKRH.
Keywords: Nonlinear cryptanalysis generalized linear cryptanalysis multidimensional linear cryptanalysis WKRH Wrong-Key Randomization Hypothesis Serpent
Contact author(s): jmclaugh @ cs york ac uk
History: 2013-02-20: received
Short URL: https://ia.cr/2013/089
License: CC BY

BibTeX

@misc{cryptoeprint:2013/089,
      author = {James McLaughlin and John A.  Clark},
      title = {Filtered nonlinear cryptanalysis of reduced-round Serpent, and the Wrong-Key Randomization Hypothesis.},
      howpublished = {Cryptology {ePrint} Archive, Paper 2013/089},
      year = {2013},
      url = {https://eprint.iacr.org/2013/089}
}