[en] We provide identity-based signature (IBS) schemes with tight security against adaptive
adversaries, in the (classical or quantum) random oracle model (ROM or QROM), in both unstructured and structured lattices, based on the SIS or RSIS assumption. These signatures are short (of
size independent of the message length). Our schemes build upon a work from Pan and Wagner
(PQCrypto’21) and improve on it in several ways. First, we prove their transformation from nonadaptive to adaptive IBS in the QROM. Then, we simplify the parameters used and give concrete
values. Finally, we simplify the signature scheme by using a non-homogeneous relation, which helps
us reduce the size of the signature and get rid of one costly trapdoor delegation. On the whole, we
get better security bounds, shorter signatures and faster algorithms.
Disciplines :
Computer science
Author, co-author :
Sageloli, Éric
Pébereau, Pierre
MEAUX, Pierrick ; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT) > PI Coron
Chevalier, Céline
External co-authors :
yes
Language :
English
Title :
Shorter and Faster Identity-Based Signatures with Tight Security in the (Q)ROM from Lattices
Publication date :
2023
Event name :
Applied Cryptography and Network Security
Event place :
Japan
Event date :
from 19-06-2023 to 22-06-2023
Audience :
International
Main work title :
Applied Cryptography and Network Security - 21st International Conference ACNS 2023, Kyoto, Japan, June 19-22, 2023, Proceedings, Part I
