Method and apparatus to protect code processed by an embedded micro-processor against altering
US11461235B2 · kind B2 · utility
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3References
20Claims
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Key dates
| Filing date | Jun 17, 2020 |
| Grant date | Oct 4, 2022 |
| Priority date | — |
| Expiry date | Feb 10, 2041 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F21/72
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method to protect code against altering includes reading immutable boot code from a ROM. A code image is loaded from an external memory and a hash is calculated by a core unit. The hash is initially authenticated using the boot code for decrypting the hash of the external memory. A salted hash for each equivalent of a cache line of the code image is concurrently calculated by a cache protection block and the salted hash for each cache line in an internal hash table is stored. If the authentication succeeds, a part of the code image is loaded into a secure cache of the embedded micro-processor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.