Improved (Again) Key Pair Generation for Falcon, BAT and Hawk

Thomas Pornin

Paper 2025/1239

Improved (Again) Key Pair Generation for Falcon, BAT and Hawk

Thomas Pornin

, NCC Group

Abstract

In this short note, we describe some further improvements to the key pair generation process for the Falcon and Hawk lattice-based signature schemes, and for the BAT key encapsulation scheme, in a fully constant-time way and without any use of floating-point operations. Our new code is slightly faster than our previous implementation, and, more importantly for small embedded systems, uses less RAM space.

Metadata

Available format(s): PDF
Category: Implementation
Publication info: Preprint.
Keywords: BAT Falcon Hawk NTRU key pair generation
Contact author(s): thomas pornin @ nccgroup com
History: 2025-07-11: approved; 2025-07-04: received; See all versions
Short URL: https://ia.cr/2025/1239
License: CC BY

BibTeX

@misc{cryptoeprint:2025/1239,
      author = {Thomas Pornin},
      title = {Improved (Again) Key Pair Generation for Falcon, {BAT} and Hawk},
      howpublished = {Cryptology {ePrint} Archive, Paper 2025/1239},
      year = {2025},
      url = {https://eprint.iacr.org/2025/1239}
}