Thursday 14 October 2021, 2:00 PM, room 3U47 and online: SSProve: A foundational framework for modular cryptographic proofs in Coq, Théo Winterhalter (MPI-SP, Bochum, Germany).

State-separating proofs (SSP) is a recent methodology for structuring game-based cryptographic proofs in a modular way. While very promising, this methodology was previously not fully formalised and came with little tool support. We address this by introducing SSProve, the first general verification framework for machine-checked state-separating proofs. SSProve combines high-level modular proofs about composed protocols, as proposed in SSP, with a probabilistic relational program logic for formalising the lower-level details, which together enable constructing fully machine-checked crypto proofs in the Coq proof assistant. Moreover, SSProve is itself formalised in Coq, including the algebraic laws of SSP, the soundness of the program logic, and the connection between these two verification styles.