Paper 2023/1468
QFESTA: Efficient Algorithms and Parameters for FESTA using Quaternion Algebras
Abstract
In 2023, Basso, Maino, and Pope proposed FESTA (Fast Encryption from Supersingular Torsion Attacks), an isogeny-based public-key encryption (PKE) protocol that uses the SIDH attack for decryption. In the same paper, they proposed a parameter for that protocol, but the parameter requires high-degree isogeny computations. In this paper, we introduce QFESTA (Quaternion Fast Encapsulation from Supersingular Torsion Attacks), a new variant of FESTA that works with better parameters using quaternion algebras and achieves IND-CCA security under QROM. To realize our protocol, we construct a new algorithm to compute an isogeny of non-smooth degree using quaternion algebra and the SIDH attack. Our protocol relies solely on $(2,2)$-isogeny and $3$-isogeny computations, promising a substantial reduction in computational costs. In addition, our protocol has significantly smaller data sizes for public keys and ciphertexts, approximately half size of the original FESTA.
Metadata
- Available format(s)
-
PDF
- Category
- Public-key cryptography
- Publication info
- Preprint.
- Keywords
- isogenyFESTASIDHSIKE
- Contact author(s)
-
kohei nakagawa @ ntt com
hiroshi-onuki @ g ecc u-tokyo ac jp - History
- 2024-06-07: last of 4 revisions
- 2023-09-25: received
- See all versions
- Short URL
- https://ia.cr/2023/1468
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2023/1468,
author = {Kohei Nakagawa and Hiroshi Onuki},
title = {{QFESTA}: Efficient Algorithms and Parameters for {FESTA} using Quaternion Algebras},
howpublished = {Cryptology {ePrint} Archive, Paper 2023/1468},
year = {2023},
url = {https://eprint.iacr.org/2023/1468}
}
