Trustworthy Measurements of a Linux Kernel and Layered Attestation via a Verified Microkernel

Layered attestation is a process by which one can establish trust in a remote party. It is a special case of attestation in which different layers of the attesting system are handled distinctly. This type of trust is desirable because a vast and growing number of people depend on networked devices to go about their daily lives. Current architectures for remote attestation are lacking in process isolation, which is evidenced by the existence of virtual machine escape exploits. This implies a deficiency of trustworthy ways to determine whether a networked Linux system has been exploited. The seL4 microkernel, uniquely in the world, has machine-checked proofs concerning process confidentiality and integrity. The seL4 microkernel is leveraged here to provide a verified level of software-based process isolation. When complemented with a comprehensive collection of measurements, this architecture can be trusted to report its own corruption. The architecture is described, implemented, and tested against a variety of exploits, which are detected using introspective measurement techniques.