Title:  Side Channel Secure Software: A Hardware Question

Abstract: We will present a method to prove the absence of power side channels in systems that are protected using masking. Power side channels may allow attackers to discover secret information by measuring electromagnetic emanations from a chip. Masking is a countermeasure to hide secrets by duplication and addition of randomness. We will discuss how to formally prove security against power side channel techniques for circuits. We will then move on to software running on a CPU, where hardware details can have surprising effects. We will present some vulnerabilities on a small CPU and how to fix them, and we will talk about contracts that take side channels into account.