On 5/15/23 21:45, Matthew Garrett wrote:
On Mon, May 15, 2023 at 09:11:15PM -0400, Daniel P. Smith wrote:
On 5/12/23 12:17, Ross Philipson wrote:
This is a good point. At this point it is really something we
overlooked. We will have to revisit this and figure out the best way to
find the final event log depending on how things booted.
I believe Ross misunderstood what you were asking for here. There are two
reasons this is not possible or desired. The first reason is that on Intel,
the DRTM log is not initialized by TrenchBoot code in the preamble. It is
only responsible for allocating a buffer and recording the location in the
TXT structures. When the SINIT ACM is executed, it will initialize the log
and record the measurement that CPU sent directly to the TPM and then the
measurements the ACM makes of the environment. If you pointed at the SRTM
log, then the ACM would write over existing log, which I don't think you
want. Now if you pointed at the tail end of the SRTM log, you would still
end up with a second, separate log that just happens to be memory adjacent.
Ok. I think it would be clearer if either the function names or some
comments expressly indicated that this refers to the DRTM event log and
that that's a separate entity from the SRTM one, "event log" on its own
is likely to cause people to think of the existing log rather than
associate it with something else.
That can be done, thanks.
