Circuit Masking: From Theory to Standardization, A Comprehensive Survey for Hardware Security Researchers and Practitioners

Side-channel attacks extracting sensitive data from implementations have been considered a major threat to the security of cryptographic schemes. This has elevated the need for improved designs by embodying countermeasures, with masking being the most prominent example. To formally verify the security of a masking scheme, numerous attack models have been developed to capture the physical properties of the information leakage as well as the capabilities of the adversary. With regard to these models, extensive research has been performed to realize masking schemes. These research efforts have led to significant progress in the development of security assessment methodologies and further initiated standardization activities. However, since the majority of this work is theoretical, it is challenging for the more practice-oriented hardware security community to fully grasp and contribute to. To bridge the gap, these advancements are reviewed and discussed in this survey, mainly from the perspective of hardware security. In doing so, a clear taxonomy is provided that is helpful for a systematic treatment of the masking-related topics. By giving an extensive overview of the existing methods, this survey (1) provides a research landscape of circuit masking for newcomers to the field, (2) offers guidelines on which attack model and verification tool to choose when designing masking schemes, and (3) identifies interesting new research directions where masking models and assessment tools can be applied. Thus, this survey serves as an essential reference for hardware security practitioners interested in the theory behind masking techniques, the tools useful to verify the security of masked circuits, and their potential applications.