Setup ACM workflow

[CharlyCst]

What/Why?

To enable trusted boot with Intel TXT, we must go through an ACM module that will setup the trusted environement. TXT is not available in QEMU, so we will need to emulate it if we want to keep the same control flow in both QEMU and on real hardware.

How?

• Create a dummy fake-acm module that can be compiled as a standalone binary, like stage 1 or stage 2
• Setup headers for the fake-acm and stage 2 (probably handled by stage 1?)
• Enable emulation of GETSEC[SENTER], might require emulating a few registers
• Jump into fake-acm, and from there to stage 2 based on headers

At this point, the control flows are identical, but the machine states are different. The next steps are to reproduce the expected environment.

• Properly setup stage 2 page tables (e.g. respect TXT constraints)
• Deactivate paging within face-acm