AprèsSQI: Extra Fast Verification for SQIsign Using Extension-Field Signing

Maria Corte-Real Santos; Jonathan Komada Eriksen; Michael Meyer; Krijn Reijnders

Paper 2023/1559

AprèsSQI: Extra Fast Verification for SQIsign Using Extension-Field Signing

Maria Corte-Real Santos

, University College London

Jonathan Komada Eriksen

, Norwegian University of Science and Technology

Michael Meyer, University of Regensburg

Krijn Reijnders, Radboud University Nijmegen

Abstract

We optimise the verification of the SQIsign signature scheme. By using field extensions in the signing procedure, we are able to significantly increase the amount of available rational $2$-power torsion in verification, which achieves a significant speed-up. This, moreover, allows several other speed-ups on the level of curve arithmetic. We show that the synergy between these high-level and low-level improvements gives significant improvements, making verification $2.07$ times faster, or up to $3.41$ times when using size-speed trade-offs, compared to the state of the art, without majorly degrading the performance of signing.

Metadata

Available format(s): PDF
Category: Public-key cryptography
Publication info: A minor revision of an IACR publication in EUROCRYPT 2024
Keywords: post-quantum cryptography isogenies SQIsign verification
Contact author(s): maria santos 20 @ ucl ac uk
jonathan k eriksen @ ntnu no
michael @ random-oracles org
krijn @ cs ru nl
History: 2024-03-05: revised; 2023-10-10: received; See all versions
Short URL: https://ia.cr/2023/1559
License: CC BY

BibTeX

@misc{cryptoeprint:2023/1559,
      author = {Maria Corte-Real Santos and Jonathan Komada Eriksen and Michael Meyer and Krijn Reijnders},
      title = {AprèsSQI: Extra Fast Verification for SQIsign Using Extension-Field Signing},
      howpublished = {Cryptology ePrint Archive, Paper 2023/1559},
      year = {2023},
      note = {\url{https://eprint.iacr.org/2023/1559}},
      url = {https://eprint.iacr.org/2023/1559}
}