(Full) Leakage resilience of Fiat-Shamir signatures over lattices

摘要

Fiat-Shamir is a mainstream construction paradigm of lattice-based signature schemes. While its theoretical security is well-studied, its implementation security in the presence of leakage is a relatively under-explored topic. Specifically, even some side-channel attacks on lattice-based Fiat-Shamir signature (FS-Sig) schemes have been proposed since 2016, little work on the leakage resilience of these schemes appears. Worse still, the proof idea of the leakage resilience of FS-Sig schemes based on traditional number-theoretic assumptions does not apply to most lattice-based FS-Sig schemes.