## Cryptology ePrint Archive: Report 2016/563

Garbling Scheme for Formulas with Constant Size of Garbled Gates

Carmen Kempka and Ryo Kikuchi and Susumu Kiyoshima and Koutarou Suzuki

Abstract: We provide a garbling scheme which creates garbled circuits of a very small constant size (four bits per gate) for circuits with fan-out one (formulas). For arbitrary fan-out, we additionally need only two ciphertexts per additional connection of each gate output wire. We make use of a trapdoor permutation for which we define a generalized notion of correlation robustness. We show that our notion is implied by PRIV-security, a notion for deterministic (searchable) encryption. We prove our scheme secure in the programmable random oracle model.

Category / Keywords: cryptographic protocols / garbled circuits, constant size of garbled gates, correlation robustness, PRIV-security

Original Publication (in the same form): IACR-ASIACRYPT-2015
DOI:
10.1007/978-3-662-48797-6_31