Analysis of reaction and timing attacks against cryptosystems based on sparse parity-check codes
Abstract
In this paper we study reaction and timing attacks against cryptosystems based on sparse parity-check codes, which encompass low-density parity-check (LDPC) codes and moderate-density parity-check (MDPC) codes. We show that the feasibility of these attacks is not strictly associated to the quasi-cyclic (QC) structure of the code but is related to the intrinsically probabilistic decoding of any sparse parity-check code. So, these attacks not only work against QC codes, but can be generalized to broader classes of codes. We provide a novel algorithm that, in the case of a QC code, allows recovering a larger amount of information than that retrievable through existing attacks and we use this algorithm to characterize new side-channel information leakages. We devise a theoretical model for the decoder that describes and justifies our results. Numerical simulations are provided that confirm the effectiveness of our approach.
Cite
@article{arxiv.1904.12215,
title = {Analysis of reaction and timing attacks against cryptosystems based on sparse parity-check codes},
author = {Paolo Santini and Massimo Battaglioni and Franco Chiaraluce and Marco Baldi},
journal= {arXiv preprint arXiv:1904.12215},
year = {2019}
}