- Cupertino CA, US Eric S. Harmon - San Francisco CA, US Mitchell K. Allison - Sunnyvale CA, US Pierre-Olivier J. Martel - Mountain View CA, US Damien P. Sorresso - San Francisco CA, US Dallas B. De Atley - San Francisco CA, US Ryan P. Nielsen - San Francisco CA, US
International Classification:
G06F 21/57 G06F 12/0875 G06F 12/14
Abstract:
In an embodiment, a system supports an external trust cache. That is, the trust cache is separate from the kernel image on the non-volatile storage in the system. During boot, the boot code may read the trust cache from the storage and write it to the working memory of the system (e.g. the Random Access Memory (RAM) forming the memory system in the system). The boot code may also validate the kernel image and write it to the memory system. The boot code may program a region register in the processor to define a region in the working memory that encompasses the kernel image and the trust cache, to protect the region from modification/tampering.
Brown stumbled upon the image while using a hex editor tool called Hex Fiend with Eric Harmon's Mac ROM template to explore the resources stored in the beige Power Mac G3's ROM. The ROM appeared in desktop, minitower, and all-in-one G3 models from 1997 through 1999.