Low Cost AES Protection Against DPA Using Rolling Codes

Many block cipher algorithms like AES are known to be weak against differential power analysis attacks (DPA) if the executing unit presents certain levels of information leakage, which is a common problem in microprocessors. Internal nonlinear functions tend to generate such information leakage which can be exploited through side-channels attacks by power line monitoring or any other means. Different countermeasures are known to be effective but at the expenses of more processing effort and therefore higher cost in terms of time and power, though not completely armored against higher order attacks. Rolling code generators (RCG) have been used for many years to avoid the man-in-the-middle attacks in wireless communications. In this paper, the effectiveness of RCG as a low cost countermeasure against AES-DPA is investigated. It has been demonstrated that it is effective to that purpose and a discussion is provided regarding the possibilities that RCG can offer protection to other types of differential side-channel attacks.