Attestation: Proving Trustability

In the last few chapters we have looked at the first stages in a process toward establishing trust between systems. First, the establishment of roots of trust and the measured boot components; and second, the collection of evidence throughout the measurement process. We reviewed the different roots of trust in a compute platform—namely, the RTM, RTS, and RTR—and how the measured boot process (S-RTM and D-RTM) uses the RTM to measure and store the evidence in the RTS. The next stage in this process is the presentation of this evidence through attestation protocols and appraisal of the evidence that asserts the integrity of a platform. This stage is referred to as attestation and verification in this book, and it is our objective for this chapter. We introduce the concept of attestation in this chapter, along with an attestation framework that defines a logical view of the assertion layers leading to attestation of specific target entities or components. The attestation provides evidence of trust and can include any device or target system participating in the trust chain. Additionally, the chapter covers one commercial implementation of the attestation solution authored by Intel and security management independent software vendors, code-named Mt. Wilson. We provide details about the solution architecture, attestation application programming interfaces (APIs), integration of these APIs into a security management function, and workload orchestration tools for decision making. We hope application developers and security specialists will gain a solid understanding of the inner workings of attestation solutions to the level of being able to carry out integration projects and even extend the paradigm.