A First-Order SCA Resistant AES without Fresh Randomness
Felix Wegener, Amir Moradi
International Workshop on Constructive Side-Channel Analysis and Secure Design, COSADE 2018, Singapore, April 23-24, 2018.
Since the advent of Differential Power Analysis (DPA) in the late 1990s protecting embedded devices against Side-Channel Analysis (SCA) attacks has been a major research effort. Even though many different first-order secure masking schemes are available today, when applied to the AES S-box they all require fresh random bits in every evaluation. As the quality criteria for generating random numbers on an embedded device are not well understood, an integrated Random Number Generator (RNG) can be the weak spot of any protected implementation and may invalidate an otherwise secure implementation. We present a new construction based on Threshold Implementations and Changing of the Guards to realize a first-order secure AES with zero per-round randomness. Hence, our design does not need a built-in RNG, thereby enhancing security and reducing the overhead.[pdf]