Dual Fine-Grained Public-Key Searchable Encryption from Lattices

Fine-grained public key encryption with keyword search (PEKS), allowing users to search on encrypted data with flexible access control policy, has been widely studied recently due to its promising application to real-world scenarios such as cloud computing. However, most of the existing fine-grained PEKS schemes are either only able to support single access control (e.g., attribute-based access control) or susceptible to being attacked or compromised by quantum computers in or after a short time. In this paper, we propose a fine-grained PEKS scheme that o ers dual access control based on lattice. In particular, we first define a dual fine-grained PEKS primitive against chosen keyword attacks under selective security. Subsequently, we adapt the key homomorphic technique and noise rerandomization technique to design a concrete scheme. Particularly, the keyword space in our construction is unlimited. Then, we present a formal security proof against chosen keyword attacks on the learning with errors (LWE) problem in the standard model. Moreover, we demonstrate the theoretical performance and experimental result of our proposed scheme. Finally, we discuss that our scheme can be easily extended to support conjunctive keywords and delegation without incurring complex operations.