Patent ID: 11947492
Assignee: SONY GROUP CORPORATION
Field: Computer technology (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 7:
8. A search method, comprising:
acquiring, from a second terminal device of a second user, an encryption search index and an identifier of the second user who searches for a document, wherein the encryption search index of a search keyword is encrypted by searchable encryption using a shared key and a verification key acquired from a first terminal device of a first user who owns the document;
acquiring an encrypted-document index generated in the first terminal device, wherein the encrypted-document index includes the search keyword included in the document and encrypted by the searchable encryption;
acquiring an encrypted document of the document encrypted and associated with the encrypted-document index;
acquiring a test key corresponding to the second user based on the acquired identifier of the second user from a database registering the test key and a re-encryption key corresponding to the second user
testing the encryption search index by using the test key;
acquiring the re-encryption key corresponding to the second user from the database based on the acquired identifier of the second user;
searching for the encrypted document from the database by using the tested encryption search index and
encrypting the searched encrypted document by the re-encryption key to generate a search result.