From: Arno Wagner <arno@wagner.name>
To: dm-crypt@saout.de
Subject: Re: [dm-crypt] Size of LUKS header and how to overwrite
Date: Wed, 10 Feb 2016 22:50:14 +0100 [thread overview]
Message-ID: <20160210215013.GA32269@tansi.org> (raw)
In-Reply-To: <56BB9D93.7020804@whgl.uni-frankfurt.de>
I should probably update the FAQ with the information about the
"payload offset" field in a separate item. Maybe "How to overwrite
only the LUKS header".
Keep in mind that much of the statements in the FAQ are still
in their first incarnation and quite a few things may lack
a simplified description, as I like to give the full story.
Hence I am grateful if anybody points out such shortcommings.
Regards and thanks,
Arno
On Wed, Feb 10, 2016 at 21:29:07 CET, Sven Eschenberg wrote:
> Ah, I see. Well the FAQ gives alternatives and more information on
> the size of the header for different keylengths and so on. But as
> the header+keymaterial can hardly be bigger than the offset of the
> encrypted payload on the backing device a dd with
> count=payload-offset and bs=512 indeed does the trick.
>
> Of course you'd have to check the payload offset of that particular
> container and not mix any numbers etc. .
>
> Regards
>
> -Sven
>
>
> Am 10.02.2016 um 21:13 schrieb Michael Kjörling:
> >On 10 Feb 2016 21:07 +0100, from sven@whgl.uni-frankfurt.de (Sven Eschenberg):
> >>Yes, it will overwrite the header and potential free space after the
> >>header up to the first sector of encrypted data.
> >>
> >>Does this seem so weird?
> >
> >No, but given the somewhat roundabout way this was described in the
> >FAQ at least last I looked, this seems like a much easier way to
> >describe it...
> >
> _______________________________________________
> dm-crypt mailing list
> dm-crypt@saout.de
> http://www.saout.de/mailman/listinfo/dm-crypt
--
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
----
A good decision is based on knowledge and not on numbers. -- Plato
If it's in the news, don't worry about it. The very definition of
"news" is "something that hardly ever happens." -- Bruce Schneier
next prev parent reply other threads:[~2016-02-10 21:50 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-02-08 22:02 [dm-crypt] Size of LUKS header and how to overwrite Rypervenche
2016-02-09 1:11 ` Arno Wagner
2016-02-09 21:28 ` Rypervenche
2016-02-09 23:28 ` Arno Wagner
2016-02-10 19:13 ` Subscriptions
2016-02-10 19:21 ` Arno Wagner
2016-02-10 19:41 ` Subscriptions
2016-02-10 20:02 ` Michael Kjörling
2016-02-10 20:07 ` Sven Eschenberg
2016-02-10 20:13 ` Michael Kjörling
2016-02-10 20:29 ` Sven Eschenberg
2016-02-10 21:50 ` Arno Wagner [this message]
2016-02-10 22:07 ` Arno Wagner
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