Using GSW FHE to provide stronger privacy protection for searchable encryption

Abstract

Nowadays, with increasingly strong awareness of privacy protection, more and more people choose to encrypt their data and then outsource it to the server, but how to search the encrypted data is a challenging problem in this situation. Many people have studied this problem, not only for the fundamental property of this, but also because there is a practical issue where the volume of data is so huge that it is impractical for users to download the whole data and search on it. One common solution is to build an inverted index using a special algorithm and support searchable algorithm on the encrypted data, but this causes another problem: the privacy will be leaked to the data owner when the owner and user are not the same person. In this paper, we design a novel scheme to solve this problem. We provide stronger privacy protection for users when they search on the data, and the scheme can protect the privacy of the inverted index table and content of data. Besides, the data owner cannot get any information about the query messages searched by users. Also, we analyse the security of our scheme, and the simulation demonstrates the good performance of our scheme.