Nonce-Misuse Resilience of Romulus-N and GIFT-COFB

Akiko Inoue; Chun Guo; Kazuhiko Minematsu

Paper 2022/1012

Nonce-Misuse Resilience of Romulus-N and GIFT-COFB

Akiko Inoue, NEC, Kawasaki Japan

Chun Guo, Shandong University

Kazuhiko Minematsu, NEC, Kawasaki Japan

Abstract

We analyze nonce-misuse resilience (NMRL) security of Romulus-N and GIFT-COFB, the two finalists of NIST Lightweight Cryptography project for standardizing lightweight authenticated encryption. NMRL, introduced by Ashur et al. at CRYPTO 2017, is a relaxed security notion from a stronger, nonce-misuse resistance notion. We proved that Romulus-N and GIFT-COFB have nonce-misuse resilience. For Romulus-N, we showed the perfect privacy (NMRL-PRIV) and n/2-bit authenticity (NMRL-AUTH) with graceful degradation with respect to nonce repetition. For GIFT-COFB, we showed n/4-bit security for both NMRL-PRIV and NMRL-AUTH notions.

Metadata

Available format(s): PDF
Category: Secret-key cryptography
Publication info: Published elsewhere. IET Information Security
Keywords: Authenticated encryption; Nonce-misuse
Contact author(s): a_inoue @ nec com
chun guo sc @ gmail com
k-minematsu @ nec com
History: 2023-02-15: revised; 2022-08-05: received; See all versions
Short URL: https://ia.cr/2022/1012
License: CC BY

BibTeX

@misc{cryptoeprint:2022/1012,
      author = {Akiko Inoue and Chun Guo and Kazuhiko Minematsu},
      title = {Nonce-Misuse Resilience of Romulus-N and GIFT-COFB},
      howpublished = {Cryptology ePrint Archive, Paper 2022/1012},
      year = {2022},
      note = {\url{https://eprint.iacr.org/2022/1012}},
      url = {https://eprint.iacr.org/2022/1012}
}