Bug#371135: [Pkg-cryptsetup-devel] Bug#371135: encrypted swap with variable key fails

[Jonas Meurer]

On 19/06/2006 Andrew Pimlott wrote:
> Automatically formatting a swap partition is a destructive operation, so
> all reasonable checks should be made before doing it.  It is currently
> not possible to positively identify a swap partition encrypted with a
> random key; nor is it possible to negatively identify a partition as not
> encrypted (with some unknown key).  This gives me two ideas:

at least we can be sure that devices with a known filesystem don't
contain encrypted data. so we can skip those.

> 1.  Create a marking for partitions to be encrypted with a random key,
>     allowing for the positive identification above.  Perhaps this should
>     be part of LUKS.

i see this more as a feature than as a bug. there may exist situations
where you don't want your device to be marked as 'contains encrypted
data'.

> 2.  If I use LUKS for all encrypted filesystems, I believe it is
>     possible to perform the negative identification above.  That is, if
>     I don't see the LUKS header, and the partition does not have an
>     unencrypted volume, then it is safe to destroy.  So let me promise
>     that I have no non-LUKS encrypted filesystems.

i'm not sure that i understand. you mean that all encrypted non-swap
devices should be LUKS devices? we should never expect that.

...
 jonas