Re: [RFC PATCH v1 3/4] tsm: Allow for mapping RTMRs to TCG TPM PCRs

[Dan Williams]

Xing, Cedric wrote:
[..]
> > So, yes, the mapping should be allowed to specified by the low-level
> > driver, but at the same time every vendor should not reinvent their own
> > enumeration method when we have EFI for that.
> 
> Given PCR->RTMR mapping is static, I just wonder why it needs to be kept 
> in kernel. Given that PCRs can never be 1:1 mapped to RTMRs, and that 
> TDX quotes are never TPM quotes, applications used to extend PCRs would 
> have to be changed/recompiled. Then wouldn't it suffice to define the 
> mappings as macros in an architecture specific header file?

I think something is wrong if applications are exposed to the PCR->RTMR
mapping thrash. I would hope / expect that detail is hidden behind a TPM
proxy layer sitting in front of this mapping on behalf of TPM-client
applications.