Visible to the public Formalizing Constructive Cryptography using CryptHOL

TitleFormalizing Constructive Cryptography using CryptHOL
Publication TypeConference Paper
Year of Publication2019
AuthorsLochbihler, Andreas, Sefidgar, S. Reza, Basin, David, Maurer, Ueli
Conference Name2019 IEEE 32nd Computer Security Foundations Symposium (CSF)
Date Publishedjun
Keywordscomplex system, Complexity theory, composability, composable cryptographic security statements, computer aided cryptography, Computer science, computer-aided cryptography, constructive cryptography, CryptHOL, cryptographic proofs, cryptography, Encryption, formal methods, formal verification, game theory, game-based proofs, information-theoretically secure channel, Probabilistic logic, proof rules, pubcrawl, random systems, theorem proving, Tools, universal composability, verification
AbstractComputer-aided cryptography increases the rigour of cryptographic proofs by mechanizing their verification. Existing tools focus mainly on game-based proofs, and efforts to formalize composable frameworks such as Universal Composability have met with limited success. In this paper, we formalize an instance of Constructive Cryptography, a generic theory allowing for clean, composable cryptographic security statements. Namely, we extend CryptHOL, a framework for game-based proofs, with an abstract model of Random Systems and provide proof rules for their equality and composition. We formalize security as a special kind of system construction in which a complex system is built from simpler ones. As a simple case study, we formalize the construction of an information-theoretically secure channel from a key, a random function, and an insecure channel.
DOI10.1109/CSF.2019.00018
Citation Keylochbihler_formalizing_2019