Re: [RFC][PATCH 0a/3] TXT: Intel(R) Trusted Execution Technology support for Linux - Overview

[Pavel Machek <pavel@suse.cz>]

Hi!

> Value Proposition for Linux or "Why should you care?"
> =====================================================
> 
> While there are many products and technologies that attempt to measure
> or
> protect the integrity of a running kernel, they all assume the kernel is
> "good" to begin with.  The Integrity Measurement Architecture (IMA) and
> Linux
> Integrity Module interface are examples of such solutions.
> 
> To get trust in the initial kernel without using Intel TXT, a static
> root of
> trust must be used.  This bases trust in BIOS starting at system reset
> and
> requires measurement of all code executed between system reset through
> the
> completion of the kernel boot as well as data objects used by that code.
> In
> the case of a Linux kernel, this means all of BIOS, any option ROMs, the
> bootloader and the boot config.  In practice, this is a lot of
> code/data, much
> of which is subject to change from boot to boot (e.g. changing NICs may
> change
> option ROMs).  Without reference hashes, these measurement changes are
> difficult to assess or confirm as benign.  This process also does not
> provide DMA protection, memory configuration/alias checks and locks,
> crash
> protection, or policy support.

Ok, I don't get it, why would I want to measure my kernel?

I see why Disney would want to do that, but I don't see why we would
want to help them.

Plus, the fact that trusted mode is pretty much incompatible with
s3/s4 makes it useless, right?

So what is this good for?

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html