Multiprocessor information concealment architecture to prevent power analysis-based side channel attacks

Abstract

Side channel attackers observe external manifestations of internal computations in an embedded system to predict the encryption key employed. The ability to examine such external manifestations (power dissipation or electromagnetic emissions) is a major threat to secure embedded systems. This study proposes a secure multiprocessor architecture to prevent side channel attacks, based on a dual-core algorithmic balancing technique, where two identical cores are used. Both cores use a single clock and encrypt simultaneously, with one core executing the original encryption, whereas the second executes the complementary encryption. This effectively balances the crucial information from the power profile (note that it is the information and not the power profile itself), hiding the actual key from the adversary attempting an attack based on differential power analysis (DPA). The two cores normally execute different tasks, but will encrypt together to foil a side channel attack. The authors show that, when our technique is applied, DPA fails on the most common block ciphers, data encryption standard (DES) and advanced encryption standard (AES), leaving the attacker with little useful information with which to perpetrate an attack.