An invariant of the round function of QARMAv2-64

Tim Beyne

Paper 2023/963

An invariant of the round function of QARMAv2-64

Tim Beyne

, KU Leuven

Abstract

This note shows that there exists a nontrivial invariant for the unkeyed round function of QARMAv2-64. It is invariant under translation by a set of $2^{32}$ constants. The invariant does not extend over all rounds of QARMAv2-64 and probably does not lead to full-round attacks. Nevertheless, it might be of interest as it can be expected to give meaningful weak-key attacks on round-reduced instances when combined with other techniques such as integral cryptanalysis.

Metadata

Available format(s): PDF
Category: Secret-key cryptography
Publication info: Preprint.
Keywords: Cryptanalysis Nonlinear invariants QARMAv2
Contact author(s): tim beyne @ esat kuleuven be
History: 2023-06-20: approved; 2023-06-19: received; See all versions
Short URL: https://ia.cr/2023/963
License: CC BY

BibTeX

@misc{cryptoeprint:2023/963,
      author = {Tim Beyne},
      title = {An invariant of the round function of {QARMAv2}-64},
      howpublished = {Cryptology {ePrint} Archive, Paper 2023/963},
      year = {2023},
      url = {https://eprint.iacr.org/2023/963}
}