From: Milan Broz <gmazyland@gmail.com>
To: Erik Logtenberg <erik@logtenberg.eu>
Cc: dm-crypt@saout.de
Subject: Re: [dm-crypt] How to increase key size of existing volume
Date: Tue, 11 Dec 2012 16:48:00 +0100 [thread overview]
Message-ID: <50C755B0.8070902@gmail.com> (raw)
In-Reply-To: <50C75290.1060003@logtenberg.eu>
On 12/11/2012 04:34 PM, Erik Logtenberg wrote:
> So there are at least two methods of extracting a master key. Now if I
> would suspect that a machine, that has a luks volume mounted, was
> compromised to the extent that someone had temporaryly gained root
> access, I would not only have to reset (all) passwords after fixing the
> security hole, but also I would have to create a new master key to be sure.
So attacker had already access to your mounted backup in plaintext
and could change anything there.
>
> Is the cryptsetup-reencrypt tool also meant for that purpose?
yes, in fact changing volume (master) key was primary use for it.
Read http://asalor.blogspot.cz/2012/08/re-encryption-of-luks-device-cryptsetup.html
(But always be sure you have backup. Backup of backup in your case :)
Milan
next prev parent reply other threads:[~2012-12-11 15:48 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-12-11 14:46 [dm-crypt] How to increase key size of existing volume Erik Logtenberg
2012-12-11 15:09 ` Arno Wagner
2012-12-11 15:34 ` Erik Logtenberg
2012-12-11 15:48 ` Milan Broz [this message]
2012-12-11 16:34 ` Arno Wagner
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=50C755B0.8070902@gmail.com \
--to=gmazyland@gmail.com \
--cc=dm-crypt@saout.de \
--cc=erik@logtenberg.eu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox