Re: [PATCH AUTOSEL 5.7 03/30] ima: extend boot_aggregate with kernel measurements

Mimi Zohar
2020-12-29T02:02:28Z

On Mon, 2020-12-28 at 14:28 -0500, Ken Goldman wrote:
> On 12/12/2020 9:22 PM, Mimi Zohar wrote:
> > Ok. Going forward, it sounds like we need to define a new
> > "boot_aggregate" record. One that contains a version number and PCR
> > mask.
>
> Just BTW, there is a TCG standard for a TPM 2.0 PCR mask that works
> well.

Sounds good.
>
> There is also a standard for an event log version number. It is
> the first event of a TPM 2.0 event log. It is strange.

Ok
>
> One useful field, though, is a mapping between the algorithm ID (e.g.,
> sha256 is 0x000b) and the digest size (e.g., 32 bytes). This permits
> a parser to parse a log even when it encounters an unknown digest
> algorithm.

The template data is prefixed with the template data length. The
problem is verifying the boot_aggregate, not parsing the log.

thanks,

Mimi