System and method for anti-rollback
US11366934B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 24, 2019 |
| Grant date | Jun 21, 2022 |
| Priority date | — |
| Expiry date | Aug 7, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F21/78
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method for providing an anti-rollback secure timer service includes determining, at a device which includes a processor providing a trusted execution environment (TEE), a trusted memory, and a real time clock (RTC) accessible through an operating system of the device, an initial reference time value, by a secure timer application running in the TEE, the initial reference time value determined based on an initial value of the RTC obtained during booting of the device and a time delta value. The method further includes determining an updated reference time value based on the initial reference time value, a second value of the RTC, and a previously stored old reference time value, determining an updated time delta value based on the second value of the RTC and the updated reference time value, and storing the updated time delta value and the updated reference time value in the trusted memory.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.