Searchable encryption system, searchable encryption method, and non-transitory computer-readable recording medium

Abstract

A searchable encryption system includes a registration device including an index generation unit () and an encrypted index generation unit (). The index generation unit () generates a registration keyword index by using a registration keyword, authorized-person attribute information corresponding to an authorized person who has an authority to search for the registration keyword, a user key function to generate a user key corresponding to a searcher, a search query function to generate a search query having the user key incorporated therein, and an index query function to generate an index query having the search query incorporated therein. The encrypted index generation unit () generates an encrypted index by encrypting the registration keyword index by using the index disclosure key.