Side Channel Attack Resistant AES Design Based on Finite Field Construction Variation

The Advanced Encryption Standard (AES) is the current standard for symmetric key cipher and is algorithmically secure. Side channel attacks that target power consumption can reveal the secret key in AES implementations. Masking data with random variables is one of the main methods used to thwart power analysis attacks. Data can be masked with multiple random variables to prevent higher-order attacks at the cost of a large increase in area. A novel masking scheme for AES resistant to second-order attacks is proposed. Instead of using an additional mask, variation in finite field construction is exploited to increase resistance to second-order attacks. As a result, the area requirement is reduced. For an example AES encryptor, the proposed design is 12% smaller compared to the previous best design, with a very small drop in achievable security level.