Continuous After-the-Fact Leakage-Resilient eCK-Secure Key Exchange

Security models for two-party authenticated key exchange (AKE) protocols have developed overtime to capture the security of AKE protocols even when the adversary learns certain secret values.Increased granularity of security can be modelled by considering partial leakage of secrets in themanner of models for leakage-resilient cryptography, designed to capture side-channel attacks. In thiswork, we use the strongest known partial-leakage-based security model for key exchange protocols,namely continuous after-the-fact leakage eCK (CAFL-eCK) model. We resolve an open problem byconstructing the first concrete two-pass leakage-resilient key exchange protocol that is secure in theCAFL-eCK model.