| 摘要 |
Computing devices that perform hardware rooted attestation are described, as are methods for use therewith, wherein such devices include a system integrated TPM (e.g., a firmware-based TPM), with m boot chain components loaded and executed prior to the system integrated TPM. Between powering-up of a device and the system integrated TPM being loaded and executed, seed morphing is performed for n=0 to m. This involves an nth encryption seed (ESn) being morphed into an n+1th encryption seed (ESn+1), under control of an nth boot chain component, by extending the nth encryption seed (ESn) with a measurement of the n+1th boot chain component to thereby generate the n+1th encryption seed (ESn+1). In a similar manner, an nth identity seed (ISn) is morphed into an n+1th identity seed (ISn+1). Such techniques establish trust in the system integrated TPM despite it not being the first component loaded and executed after powering-up. |
| 主权项 |
1. A method for hardware rooted attestation of a computing device having a system integrated trusted platform module (TPM), wherein in components in a boot chain for the computing device are loaded and executed prior to the system integrated TPM being loaded and executed by the computing device, wherein m≧2, the method comprising:
after powering-up of the computing device, but before the system integrated TPM is loaded and executed by the computing device, performing the following, for n=0 to m, wherein n is an integer incremented by 1,
(a) morphing an nth encryption seed (ESn) into an n+1th encryption seed (ESn+1), under control of an nth component in the boot chain, by extending the nth encryption seed (ESn) with a measurement of the n+1th component in the boot chain to thereby generate the n+1th encryption seed (ESn+1); and(b) morphing an nth identity seed (ISn) into an n+1th identity seed (ISn+1), under control of the nth component in the boot chain, by extending the nth identity seed (ISn) with a measurement of the n+1th component in the boot chain to thereby generate the n+1th identity seed (ISn+1); wherein an initial encryption seed ES0, which corresponds to n=0, comprises a root encryption seed (RES) that is unique to the computing device; wherein an initial identity seed IS0, which corresponds to n=0, comprises a root identity seed (RIS) that is unique to the computing device; and wherein at least one of the RES and the RIS is immutably stored in hardware of the computing device. |
