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

Claim 8:
9. A search method, comprising:
acquiring, from a first terminal device of a first user who owns a document, a shared key and a verification key used in encryption of a search keyword and a decryption key for decrypting a search result received from an information processing device;
when input of the search keyword is received from the second user, generating an encryption search index by using the shared key and the verification key and transmitting the encryption search index together with an identifier of the second user to the information processing device;
acquiring the test key and a re-encryption key corresponding to the second user based on the identifier of the second user from a database registering the encrypted-document index of the search keyword included in the document encrypted by searchable encryption, an encrypted document associated with the encrypted-document index, and the test key and the re-encryption key corresponding to the second user;
testing the encryption search index by using the test key;
searching for the encrypted document from the database by using the tested encryption search index;
receiving a search result including the searched encrypted document encrypted by the re-encryption key from the information processing device and
decrypting the received search result by using the decryption key.