Almost Optimal Oblivious Transfer from QA-NIZK
Résumé
We show how to build a UC-Secure Oblivious Transfer in the presence of Adaptive Corruptions from Quasi-Adaptive Non-Interactive Zero-Knowledge proofs. Our result is based on the work of Jutla and Roy at Asiacrypt 2015, where the authors proposed a constant-size very efficient PAKEPAKE scheme. As a stepping stone, we first show how a two-flow PAKEPAKE scheme can be generically transformed in an optimized way, in order to achieve an efficient three-flow Oblivious-Transfer scheme. We then compare our generic transformations to existing OT constructions and see that we manage to gain at least a factor 2 to the best known constructions. To the best of our knowledge, our scheme is the first UC-secure Oblivious Transfer with a constant size flow from the receiver, and nearly optimal size for the server.
Domaines
Cryptographie et sécurité [cs.CR]
Origine : Fichiers produits par l'(les) auteur(s)
Loading...