Re: the cold-boot attack

* [email protected] wrote:

> So as a conclusion of the mentioned time-limited vulnerability
> should I remount the side wall of my computer case again? Maybe
> even replace the original crossheads with tri-wing screws? To put
> it in a nutshell, I fiercely doubt todays police forces are that
> talented, since they fail to simply boot up a computer.

I still keep my case open.

But the one strategy against the attack is denying physical access to
the machine. Apart from that, I have to slightly adapt my loop-AES
scheme now, I'm not worried.


> The described attack has nothing to do with breaking the encryption
> as such. Compared to this it would also be an option to point with
> a gun at your temple and simply ask for keys/passphrases. As a
> reaction to this "attack" I wonder if it might be possible to use
> level 2 cache of the processor to store keys in highly volatile
> memory space. 2 or more megabytes on the CPU die might be a last
> resort. As gpg prevents leaking keys from kernel ram to swap
> partitions, newer disk encryption might prevent keys to be stored
> in DRAM cells. Of course, elderly processors might not do this
> stunt due to lack of level 1/2/3 cache but newer architectures
> offer ever increasing megabytes. Is that a worthwhile option?

Hm. I doubt CPU level 2 (or so) cache is directly accessible but is
used by the CPU itself. Maybe it would be possible by using adapted
microcode (on Intel chips). 

Thinking along those lines ... cache of other components might be
worth looking into: graphics cards, hard disk drive cache...


-- 
left blank, right bald

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