Predicate encryption, formalized by Katz, Sahai, and Waters (EUROCRYPT 2008), is an attractive branch of public-key encryption, which provides fine-grained and role-based access to encrypted data. As for many multi-user cryptosystems, an efficient revocation mechanism is necessary and imperative in the context of predicate encryption, in order to address scenarios when users misbehave or their private keys are compromised. The formal model of revocable predicate encryption was introduced by Nieto, Manulis and Sun (ACISP 2012), who suggest the strong, full-hiding security notion, demanding that the ciphertexts do not leak any information about the encrypted data, the attribute and the revocation information associated with it. In this work, we introduce the first construction of lattice-based revocable predicate encryption. Our scheme satisfies the full-hiding security notion (in a selective manner) in the standard model, based on the hardness of the Learning With Errors (LWE) problem. In terms of asymptotic efficiency, the scheme is somewhat comparable to the pairing-based instantiation put forward by Nieto, Manulis and Sun. Furthermore, better efficiency could be easily achieved in the random oracle model.
展开▼
