Fine-Grained Searchable Encryption Scheme Against Keyword Brute-Force Attacks

The inherent security threat of public key encryption with keyword search (PEKS) is the inside guessing attack since the ciphertext of keyword is generated publicly. Sever-aided schemes and keyword search with authenticated encryption schemes are proposed to resist inside keyword guessing attack in PEKS. Unfortunately, these solutions have limitations due to the security and privacy. To overcome these weakness, we propose an encrypted keyword search with fine-grained access control. The access policy of our scheme is semi-hidden in order to prevent the behavior of online keyword guessing attacks. At the same time, our scheme achieves offline keyword guessing attacks resistant by the private generation of ciphertext (without using the private key). Security proofs and experiment results show that our solution is feasible in terms of security and performance.