Re: [dm-crypt] dm-crypt "inverted" usage (i.e. exporting an "encrypted" image of a block device)

[Arno Wagner <arno@wagner.name>]

On Thu, Aug 01, 2013 at 12:41:34PM +0200, Milan Broz wrote:
> 
> On 08/01/2013 11:49 AM, Ciprian Dorin Craciun wrote:
> > On Thu, Aug 1, 2013 at 10:43 AM, Milan Broz <gmazyland@gmail.com> wrote:
> >> On 1.8.2013 9:00, Ciprian Dorin Craciun wrote:
> >>>
> >>>      As said, I guess this can be obtained in two ways:
> >>>      * either if there is a "backward" mode for dm-crypt;  (which I'm
> >>> not aware of;)
> >>
> >>
> >> No, there is not.
> >>
> >> I hope I understand your use case correctly, bu if so, this mode
> >> (transport over network) _cannot_ be secure.
> > 
> >     Indeed such a solution I'm after won't be "completely" secure (as
> > a matter of fact nothing can be completely as that would imply
> > perfection).  And in my particular use case I don't need it.
> 
> Well, you have been warned... and you can always shoot yourself in the foot ;-)

And you will. Even exporting the encrypted block device is 
insecure (i.e. "doing it right"), as disk encryption
has a different attacker mdoel than communication encryption
and different limitations. If, at some time, you decide you 
actually want to be secure, move to any VPN-tunnel like 
solution.

Arno 

-- 
Arno Wagner,     Dr. sc. techn., Dipl. Inform.,    Email: arno@wagner.name
GnuPG: ID: CB5D9718  FP: 12D6 C03B 1B30 33BB 13CF  B774 E35C 5FA1 CB5D 9718
----
There are two ways of constructing a software design: One way is to make it
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