Threshold Implementation in Software

Abstract

Masking is one of the predominantly deployed countermeasures in order to prevent side-channel analysis (SCA) attacks. Over the years, various masking schemes have been proposed. However, the implementation of Boolean masking schemes has proven to be difficult in particular for embedded devices due to undisclosed architecture details and device internals. In this article, we investigate the application of Threshold Implementation (TI) in terms of Boolean masking in software using the PRESENT cipher as a case study. Since TI has proven to be a proper solution in order to implement Boolean masking for hardware circuits, we apply the same concept for software implementations and compare it to classical first- and second-order Boolean masking schemes. Eventually, our practical security evaluations reveal that amongst all our considered implementation variants only the TI can provide first-order security while all others still exhibit detectable first-order leakage.