Re: [PATCH 0/4] Add support for TPM2 log reported via ACPI table

[Ken Goldman <kgold-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>]

On 3/30/2017 4:13 AM, Petr Vandrovec wrote:
> Nayna wrote:
>>
>>
>> On 03/29/2017 01:13 PM, Petr Vandrovec wrote:
>> [snip]
>>> tpm2_eventlog.c uses log uses native endianness. If it
>>> is intentional, and PPC64 has TPM1 logs in big endian
>>
>> Yes, in case of ppc64, the tpm1 code logs are in big endian format.
>
> Thanks.  What about tpm2 logs?  Is first (specid) event in big endian
> format too, or no?

Formally, according to the TCG specifications, the firmware event log
is little endian.

My opinion (but I may be wrong) ...

It doesn't matter, as long as the platform knows what it did.

When the platform sends the log to the attestation server, it should be
a consistent format, regardless of the endian'ness of the platform.

In my attestation implementation, I use big endian, because that's what
the TPM uses. Thus, I reuse all the TPM and TSS marshaling and
unmarshaling code.


------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot