Presented at CHES 2022 conference


FortifyIQ presents RAMBAM - a novel concept of designing countermeasures against side-channel attacks and the Statistical Ineffective Fault Attack (specifically SIFA-1) on AES that employs redundant representations of finite field elements.

A fundamental property of RAMBAM is a security parameter d that along with other attributes of the scheme allows for making trade-offs between gate count, maximal frequency, performance, level of robustness to the first and higher-order side-channel attacks, and protection against SIFA-1. From this concept, FortifyIQ derives a family of protected hardware implementations of AES.

FortifyIQ presents an analytical model that explains how the scheme reduces the leakage and how the design choices affect it. Furthermore, FortifyIQ demonstrates experimentally how different design choices achieve the required goals. In particular, the compact version exhibits a gate count as low as 12.075 kGE, while maintaining adequate protection. The performance-oriented version provides latency as low as one round per cycle, thus combining protection against SCA and SIFA-1 with high performance.