Re: [GIT PULL] x86/txt for v2.6.32

[Arjan van de Ven <arjan@infradead.org>]

On Sat, 3 Oct 2009 17:36:20 -0300
Henrique de Moraes Holschuh <hmh@hmh.eng.br> wrote:

> On Sat, 03 Oct 2009, Pavel Machek wrote:
> > On Sat 2009-10-03 01:02:52, Wang, Shane wrote:
> > > > So I modify the RAM content so that BIOS does not think measured
> > > > environment existed before suspend?
> > > > 									Pavel
> > > 
> > > Hi Pavel, what do you mean on this question? 
> > > When do you modify the RAM? before S3 sleep?
> > 
> > During the sleep, using something cold and second machine.
> 
> And it is ridiculously easy to pull off, too:
> http://www.engadget.com/2008/02/21/cold-boot-disk-encryption-attack-is-shockingly-effective/
> 
> Shows the attack being used to read sensitive keys, but you can use
> it also to *modify* system running state (it will be more difficult,
> as you need to remove and replace the RAM while on S3 instead of S5,
> but it should be doable by someone who knows what he is doing).
> 

that assumes all state is in ram, and not some bit in the TPM..

(and as for that "we can steal the content"... that's confusing DRM
with TXT. TXT is integrity, DRM is. well evil ;-)


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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