A Probabilistic Logic for Concrete Security
Abstract
The Squirrel Prover is a proof assistant designed for the computational verification of cryptographic protocols. It
implements a probabilistic logic that captures cryptographic and probabilistic arguments used in security proofs. This logic operates
in the asymptotic security setting, which limits the expressiveness of formulas and proofs. As a consequence, it can only prove
security for finite interactions with a protocol, falling outside of the polynomial-level of security usually expected by cryptographers.
We lift all these limitations by moving to a concrete security setting. We extend the logic with concrete security predicates,
and design a corresponding proof system. We show the usefulness of these extensions on a case study,
and through a novel proof-transformation result which shows that a large class of asymptotic
logic security proofs can be automatically rewritten into concrete logic security proofs, improving security bounds exponentially.
Domains
Computer Science [cs]Origin | Files produced by the author(s) |
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Licence |