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From: Heinz Diehl <htd@fancy-poultry.org>
To: dm-crypt@saout.de
Subject: Re: [dm-crypt] passfrase or dev_random for keyfile of a dmcrypt_swap
Date: Wed, 21 Apr 2010 10:34:17 +0200	[thread overview]
Message-ID: <20100421083417.GA6910@fancy-poultry.org> (raw)
In-Reply-To: <20100420141506.845AC44B6C@ws5-1.us4.outblaze.com>

On 20.04.2010, Si St wrote: 

> To Heinz: Would not a pre-generated keyfile need to be opened by a passfrase?

No, the keyfile itself is the "passphrase". I'm not talking about the
master key here, what I mean is something like

 dd if=/dev/urandom of=keyfile bs=64 count=1
 cryptsetup luksFormat /dev/sdx /path/to/keyfile
 
You could now e.g. do something like

 swap /dev/sdx /path/to/keyfile swap
 
in your crypttab, save the keyfile somewhere on the encrypted root
partition and open the swapspace using a bootscript after your root partition 
has been mapped. You could then backup the keyfile in a safe place and use
it to map the swap partition manually if desired (in the scenario you
described).

  parent reply	other threads:[~2010-04-21  8:34 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-04-20 14:15 [dm-crypt] passfrase or dev_random for keyfile of a dmcrypt_swap Si St
2010-04-20 15:15 ` Arno Wagner
2010-04-21  8:34 ` Heinz Diehl [this message]
2010-04-21  9:06   ` Jonas Meurer
  -- strict thread matches above, loose matches on Subject: below --
2010-04-20 18:06 Si St
2010-04-20 19:14 ` Arno Wagner
2010-04-19 16:37 Si St
2010-04-19 16:54 ` Arno Wagner
2010-04-19 19:01 ` Heinz Diehl
2010-04-20  5:41 ` Luca Berra

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