Re: [dm-crypt] loop file with partition problems

[Arno Wagner <arno@wagner.name>]

On Wed, Feb 29, 2012 at 05:26:03PM +0100, Giovanni Di Stasi wrote:
> Hi everyone,
> 
> I am having problems accessing a partition I have created on a file.
> I have never managed to mount it after reboot.
> I am using Debian (testing).
> 
> This is what I did:
> 
> # sudo -i
> # echo aes >> /etc/modules
> # echo dm_mod >> /etc/modules
> # echo dm_crypt >> /etc/modules
> # dd if=/dev/urandom of=.encrypted bs=1024 count=500000
> # sudo cryptsetup -y create crypt .encrypted
> # echo "crypt /home/giovanni/.encrypted none none" >> /etc/crypttab
> # sudo mkfs.ext4 /dev/mapper/crypt
> # mkdir /home/giovanni/cip
> # chown giovanni:giovanni /home/giovanni/cip/
> # sudo mount /dev/mapper/crypt /home/giovanni/cip
> # ls /home/giovanni/cip/
> # sudo umount /home/giovanni/cip
> # sudo mount /dev/mapper/crypt /home/giovanni/cip
> 
> After rebooted, I don't really know how to mount my partition.
> I have tried this:
> 
> # sudo -i
> # cryptsetup luksOpen .encrypted crypt
> Device /dev/loop0 is not a valid LUKS device.
> 
> Did I lost all my data as I suspect? If so, why?

You are confusing plain dm-crypt and LUKS. You created the 
crypto-container (which is not a partition but a whole 
decive here) as plain dm-crypt and are trying to map it
as LUKS. These two are different and not compatible.

Try this:

 cryptsetup create crypt .encrypted
 mount /dev/mapper/crypt /home/giovanni/cip

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