[dm-crypt] Verify LUKS password

Arno Wagner arno at wagner.name
Tue Nov 29 18:31:24 CET 2011

I am not clear on what you want to do: Use the LUKS passphrase
also for the Gnome screen-locker? If so, set one of the keyslots
to the passphrase of the screen-locker.

If you actually want to remove the LUKS mapping (i.e. "close" the
LUKS container) when the screen safer engages and remap the LUKS
container when the screensaver is unlocked, then this is complicated.
It mau also not be what you want, given that unmapping the LUKS
container with open files is eiter not possible or can result in
arbitrary data corruption (I have not tried it). So you would
need to do something like this on screenlocker-engage:

1. Determine all open files in the LUKS container
2. Terminate all applications that have these files open
3. Unmount the LUKS container and verify it did unmount.
   If unmount fails, go to 1. (An application could have opened
   a file in between...) Maybe you can also do a ro remount first.
4. Unmap the LUKS container.

Now, this would need to be somehow script-driven from the 
screensaver. Whether automated application clsoe is a good idea 
depends very much on the situation and is generally _not_ a good 


On Tue, Nov 29, 2011 at 01:22:35PM -0200, Marcos Barbosa wrote:
> I have a problem: I need authenticate gnome-screensaver (via PAM) with LUKS
> password. How i do that?
> Best regards.
> -- 
> Marcos Barbosa <marcosestevesbarbosa at gmail.com>

> _______________________________________________
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> dm-crypt at saout.de
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Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno at wagner.name 
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