Virtually Free Randomisations of NTT in RLWE Cryptosystem to Counteract Side Channel Attack Based on Belief Propagation

Christophe Negre, Mbaye Ngom, Mbaye Ngom

2024

Abstract

At CHES 2017, Primas, Pessl and Mangard presented an attack on RLWE cryptosystem based on Belief Propagation. The attack applies on the Number Theoretic Transform (NTT) used to decipher a message. It gathers power consumption leakage of the multiplication by roots of unity in the NTT and then applies Belief Propagation to circulate the information of all leakage nodes, until the combined leakage reveal most of the output coefficients of the NTT. In this paper we present some randomisations which either induce in NTT some random mask on values or randomly rearrange the sequence of operations. We evaluate the level of randomisation provided by the proposed counter-measures and also the effect on the processed values in the NTT. We apply Belief Propagation on the proposed randomised NTT and we study how these randomisations affect the attack. Finally we point out that a set of three combined strategies provide a high level of randomisation and a good protection against Belief Propagation attack of Primas et al.

Paper Citation

in Harvard Style

Negre C. and Ngom M. (2024). Virtually Free Randomisations of NTT in RLWE Cryptosystem to Counteract Side Channel Attack Based on Belief Propagation. In Proceedings of the 21st International Conference on Security and Cryptography - Volume 1: SECRYPT; ISBN 978-989-758-709-2, SciTePress, pages 866-875. DOI: 10.5220/0012857500003767

in Bibtex Style

@conference{secrypt24,
author={Christophe Negre and Mbaye Ngom},
title={Virtually Free Randomisations of NTT in RLWE Cryptosystem to Counteract Side Channel Attack Based on Belief Propagation},
booktitle={Proceedings of the 21st International Conference on Security and Cryptography - Volume 1: SECRYPT},
year={2024},
pages={866-875},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0012857500003767},
isbn={978-989-758-709-2},
}

in EndNote Style

TY - CONF

JO - Proceedings of the 21st International Conference on Security and Cryptography - Volume 1: SECRYPT
TI - Virtually Free Randomisations of NTT in RLWE Cryptosystem to Counteract Side Channel Attack Based on Belief Propagation
SN - 978-989-758-709-2
AU - Negre C.
AU - Ngom M.
PY - 2024
SP - 866
EP - 875
DO - 10.5220/0012857500003767
PB - SciTePress