EBBR Notes 2021.11.22

Attendees:

Agenda

UEFI EBBR Conformance profile (Jose)
- https://bugzilla.tianocore.org/show_bug.cgi?id=3591
Requirements for measured boot (Ilias)

The UEFI USWG has been discussing what we've done in EBBR to require a subset of the UEFI spec. They have recognized that there is value in the subset definition
- New config table defined with a GUID identifying EBBR_2_0 compliance
- A future 3.0 EBBR will require a new GUID
No investigation has been done yet on implementing in U-Boot
- (Ilias) if it is a config table then we can go ahead and add it

U-Boot is getting very compliant to the TCG profile for TPM measurements (estimated 90% coverage)
Missing details
- DTB is not measured
Should EBBR required TCG compliance if a TPM is present?
The TCG doesn't have any language about DTB testing, how should the DTB be measured?
(Grant) it is difficult to require 'optional' features in EBBR. How can we enforce TPM support when a vendor can just say we don't support that?
(Ricardo) DTB measurement is important if doing measured boot -- need a solution here
- (Ilias) maybe we should define a method for DTB measurement and propose it to the TCG
- Ilias is discussing measurement approach with U-Boot developers
- Should measured DTB be the 'original' dtb provided to U-Boot, or the DTB after U-Boot has applied fixups?
(Grant) in terms of enforcement, the SystemReady IR certification program can allow for optional interfaces, but fail if the interface is implemented correctly.
(Ilias) Are there other firmware stack implementations implementing TCG protocols?
- (Grant) There is code in EDK2, but I don't know of anyone actively working on EBBR compliant EDK2 with TCG enabled.
Feedback from group on making SecureBoot enabled in EBBR v3.0
- Would prefer SecureBoot be an well specified option rather than outright required on all platforms
- Needs to be really well defined so that there is not a lot of variability

Action: Ilias to talk to Stuart Yoder about working with TCG