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

Claim 6:
7. A terminal device, comprising:
an acquisition unit configured to:
acquire, 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 to decrypt a search result received from an information processing device;

a generation unit configured to:
generate, when input of the search keyword is received from a second user, an encryption search index by using the shared key and the verification key, and
transmit the encryption search index together with an identifier of the second user to the information processing device;

a decryption unit configured to:
acquire 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;
test the encryption search index by using the test key;
search for the encrypted document from the database by using the tested encryption search index;
receive a search result that includes the searched encrypted document encrypted by the re-encryption key from the information processing device, and
decrypt the received search result by using the decryption key.