Re: Hibernation considerations

Vojtech Pavlik
2007-07-29T06:53:52Z

On Mon, Jul 16, 2007 at 12:38:11AM +0200, Rafael J. Wysocki wrote:

> > Or the user unplugs their flash drive after hibernation rather than before.
> >
> > Two things which I think would be nice to consider are:
> > 1) Encryption - I'd actually prefer if my luks device did not
> > remember the key accross a hibernation; I want to be forced to
> > reenter the phrase. However I don't know what the best thing
> > to do to partitions/applications using the luks device is.
>
> Encryption is possible with both the userland hibernation (aka uswsusp) and
> TuxOnIce (formerly known as suspend2). Still, I don't consider it as a "must
> have" feature for a framework to be generally useful (many users don't use it
> anyway).

If a user uses an encrypted filesystem, then he also needs an encrypted
swap and encrypted hibernation image: Otherwise the fileystem encryption
is not very useful.

Forgetting the filesystem/swap decryption keys before hibernation is
probably harder to do - there may be sensitive data in the kernel memory
image that weren't cleared - even if the key itself is not there.

In my opinion, encrypted hibernation is what every notebook user should
want - that's the only way how to make sure data from the notebook
aren't available when the notebook is physically stolen.

--
Vojtech Pavlik
Director SuSE Labs