Functional Encryption for Inner Product Predicates from Learning with Errors

We propose a lattice-based functional encryption scheme for inner product predicates whose security follows from the difficulty of the learning with errors (LWE) problem. This construction allows us to achieve applications such as range and subset queries, polynomial evaluation, and CNF/DNF formulas on encrypted data. Our scheme supports inner products over small fields, in contrast to earlier works based on bilinear maps. Our construction is the first functional encryption scheme based on lattice techniques that goes beyond basic identity-based encryption. The main technique in our scheme is a novel twist to the identity-based encryption scheme of Agrawal, Boneh and Boyen (Eurocrypt 2010). Keywords. Functional encryption, predicate encryption, lattices, learning with errors. ∗ Part of this work done while at Microsoft Research Redmond. Research supported in part from a DARPA/ONR PROCEED award, and NSF grants 1118096, 1065276, 0916574 and 0830803. † Research supported by NSF an...

• Type: Journal
• Year: 2011
• Where: ASIACRYPT
• Authors: Shweta Agrawal, David Mandell Freeman, Vinod Vaikuntanathan
• Keywords: ASIACRYPT 2011, Cryptology, DNF Formulas, NSF Grants, Polynomial Evaluation