Method for protecting encrypted control word, hardware security module, main chip and terminal
US11308242B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Feb 9, 2018 |
| Grant date | Apr 19, 2022 |
| Priority date | — |
| Expiry date | Mar 13, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/4623
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Provided is a method for protecting an encrypted control word. The method includes: receiving a hardware security module entitlement management message and an encrypted control word transmitted from a main chip, where the hardware security module entitlement management message includes a key for decrypting the encrypted control word; decrypting, based on the hardware security module entitlement management message and a hardware security module root key stored in the hardware security module, the encrypted control word to obtain a control word; reencrypting the control word based on a re-encryption key stored in the hardware security module to obtain a reencrypted control word; and transmitting the reencrypted control word to the main chip, so that the main chip decrypts, based on a main chip entitlement management message transmitted from the front end, the reencrypted control word to obtain the control word.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.