Weak Subtweakeys in SKINNY

Daniël Kuijsters; Denise Verbakel; Joan Daemen

Paper 2022/1042

Weak Subtweakeys in SKINNY

Daniël Kuijsters, Radboud University Nijmegen

Denise Verbakel, Radboud University Nijmegen

Joan Daemen, Radboud University Nijmegen

Abstract

Lightweight cryptography is characterized by the need for low implementation cost, while still providing sufficient security. This requires careful analysis of building blocks and their composition. SKINNY is an ISO/IEC standardized family of tweakable block ciphers and is used in the NIST lightweight cryptography standardization process finalist Romulus. We present non-trivial linear approximations of two- round SKINNY that have correlation one or minus one and that hold for a large fraction of all round tweakeys. Moreover, we show how these could have been avoided.

Metadata

Available format(s): PDF
Category: Secret-key cryptography
Publication info: Preprint.
Keywords: cryptanalysis lightweight symmetric cryptography block ciphers
Contact author(s): daniel kuijsters @ ru nl
denise verbakel @ ru nl
joan daemen @ ru nl
History: 2022-08-17: approved; 2022-08-11: received; See all versions
Short URL: https://ia.cr/2022/1042
License: CC0

BibTeX

@misc{cryptoeprint:2022/1042,
      author = {Daniël Kuijsters and Denise Verbakel and Joan Daemen},
      title = {Weak Subtweakeys in SKINNY},
      howpublished = {Cryptology ePrint Archive, Paper 2022/1042},
      year = {2022},
      note = {\url{https://eprint.iacr.org/2022/1042}},
      url = {https://eprint.iacr.org/2022/1042}
}