Integrity Preserving Multi-keyword Searchable Encryption for Cloud Computing

Abstract

Searchable symmetric encryption is an efficient way to perform keyword search over encrypted data in cloud storage. However, most existing methods do not take into account the integrity verification of the search result. Moreover, existing methods can only verify the integrity of single-keyword search results, which cannot meet the requirements of multi-keyword conjunctive search. To address this problem, we proposed a multi-keyword searchable encryption scheme with an authentication mechanism that can efficiently verify the integrity of search results. The proposed scheme is based on the searchable symmetric encryption and adopts the bilinear map accumulator to prove the correctness of set operations. It supports multiple keywords as input for conjunctive search and gives the server the ability to prove the integrity of the search result to the user. Formal proofs show that the proposed scheme is unforgeable and adaptive secure against chosen-keyword attacks. To the best of our knowledge, this is the first work that can authenticate the multi-keyword search result over encrypted data.