Paper 2016/630

Decomposed S-Boxes and DPA Attacks: A Quantitative Case Study using PRINCE

Ravikumar Selvam, Dillibabu Shanmugam, Suganya Annadurai, and Jothi Rangasamy

Abstract

Lightweight ciphers become indispensable and inevitable in the ubiquitous smart devices. However, the security of ciphers is often subverted by various types of attacks, especially, implementation attacks such as side-channel attacks. These attacks emphasise the necessity of providing efficient countermeasures. In this paper, our contribution is threefold: First, we observe and resolve the inaccuracy in the well-known and widely used formula for estimation of the number of gate equivalents (GE) in shared implementation. Then we present the first quantitative study on the efficacy of Transparency Order (TO) of decomposed S-Boxes in thwarting a side-channel attack. Using PRINCE S-Box we observe that TO-based decomposed implementation has better DPA resistivity than the naive implementation. To benchmark the DPA resistivity of TO(decomposed S-Box) implementation we arrive at an efficient threshold implementation of PRINCE, which itself merits to be an interesting contribution.