Re: [dm-crypt] cryptsetup support for dm-crypt suspend/resume

[Arno Wagner <arno@wagner.name>]

On Fri, Aug 28, 2009 at 11:46:17AM +0200, Martin Milata wrote:
> On Fri, Aug 28, 2009 at 07:21:36 +0200, Arno Wagner wrote:
> > Makes sense and increases security. I am wondering however whether
> > this could just be scripted by
> > 1) Store all parameters besides key in some file
> > 2) Completely remove and umount the device before suspend.
> > 3) An resume: Use a wraper around dm-crypt that gets the parameters 
> >    from the file, asks for the password and initializes and mounts 
> >    the device just as if it was newly created.
> 
> If I understand it correctly, this would require unmounting the
> partition (and thus killing all programs using it), which I would like
> to avoid. And cached contents of the filesystem would probably remain in
> RAM anyway.

I am not sure you even can remove the mapping (and hence
the encryption) without umounting. If you can, that would
be better, obviously but then you likely have to do that
with specialised code.

But this may be a case where suspending is not really 
possible.

Arno

-- 
Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno@wagner.name 
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