METHOD FOR SEARCHABLE ENCRYPTION AND METHOD FOR SEARCHING OF ENCRYPTED DATA

摘要

The present invention relates to a searchable encryption method and an encrypted data searching method. The method comprises: a preparation step of generating an index consisting of keywords, extracted from data to be stored in a server, and a list of the frequency of each keyword and generating keys for encryption and decryption; an encryption step of respectively encrypting the data, the keywords in the index and the keyword frequency in the index by using the encryption key and storing the encryption result in the server; a search reference generation step of generating a search reference including a search keyword for searching the encrypted data from the server, and encrypting the generated search reference through proxy re-encryption; a search query generation step of generating a search query based on the encrypted search reference, and encrypting the generated search query through homomorphic encryption before transmitting the encrypted search query to the server; a search query evaluation step of performing, by the server, evaluation of the encrypted search query in the encryption state to derive a search query evaluation resu and a data detection step of detecting desired data based on the search query evaluation result. [Reference numerals] (AA) Start; (BB) End; (S110) Preparation step; (S120) Encryption step; (S130) Search reference generation step; (S140) Search query generation step; (S150) Search query evaluation step; (S160) Data detection step