[dm-crypt] Wrong behavior?

Arno Wagner arno at wagner.name
Wed Jul 14 12:09:33 CEST 2010

On Wed, Jul 14, 2010 at 08:38:56AM +0200, Heinz Diehl wrote:
> On 14.07.2010, MkFly wrote: 
> > Well now I'm wondering, does luksFormat use /dev/urandom for
> > master-key generation?
> Yes, it does.
> > ?If so, is there any way to force it to use
> > /dev/random instead (aside from generating a keyfile beforehand and
> > luksFormat'ing with --master-key-file)?
> If I remember correctly, this has been discussed here before, and one of
> the main reasons against using /dev/random was that it's blocking when
> it's out of entropy.

Specifically, the issue was what to do in a low-entropy environment
(embedded system) on automatic install. On an ordinary PC on second
boot or so, /dev/urandom typically produces very good key material.


Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno at wagner.name 
GnuPG:  ID: 1E25338F  FP: 0C30 5782 9D93 F785 E79C  0296 797F 6B50 1E25 338F
Cuddly UI's are the manifestation of wishful thinking. -- Dylan Evans

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