## Cryptology ePrint Archive: Report 2018/934

Integrative Acceleration of First-Order Boolean Masking for Embedded IoT Devices

Yuichi Komano and Hideo Shimizu and Hideyuki Miyake

Abstract: Physical attacks, especially side-channel attacks, are threats to IoT devices which are located everywhere in the field. For these devices, the authentic functionality is important so that the IoT system becomes correct, and securing this functionality against side-channel attacks is one of our emerging issues. Toward that, Coron et al. gave an efficient arithmetic-to-Boolean mask conversion algorithm which enables us to protect cryptographic algorithms including arithmetic operations, such as hash functions, from the attacks. Recently, Biryukov et al. improved it by locally optimizing subroutines of the conversion algorithm. In this paper, we revisit the algorithm. Unlike Biryukov et al., we improve the Coron et al.'s algorithm with integrative optimizations over the subroutines. The gains against these algorithms are about $22.6\%$ and $7.0\%$ in the general setting. We also apply our algorithm to HMAC-SHA-1 and have an experiment to show that the implementation on a test vehicle smartcard leaks no sensitive information with the ISO/IEC17825 test.

Category / Keywords: implementation / side-channel attack, mask conversion, IoT, embedded device