Decryption device, encryption device, and cryptographic system
US11533176B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Oct 16, 2020 |
| Grant date | Dec 20, 2022 |
| Priority date | — |
| Expiry date | Feb 9, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L9/30
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
An inner-product functional encryption scheme in which the maximum length of a ciphertext and the maximum length of a secret key are not restricted can be constructed. An encryption device (20) generates a ciphertext ctx in which a vector x is encrypted, using encryption setting information that is of a size depending on the size of the vector x and is generated using as input public information of a fixed size. A key generation device (30) generates a secret key sky in which a vector y is set, using key setting information that is of a size depending on the size of the vector y and is generated using as input the public information. A decryption device (40) decrypts the ciphertext ctx with the secret key sky to calculate an inner-product value of the vector x and the vector y.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.