From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <qlefebvre_pro@yahoo.com>
Received: from nm14-vm9.bullet.mail.ir2.yahoo.com
 (nm14-vm9.bullet.mail.ir2.yahoo.com [212.82.96.197])
 (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits))
 (No client certificate requested)
 by mail.server123.net (Postfix) with ESMTPS
 for <dm-crypt@saout.de>; Wed, 19 Nov 2014 22:24:46 +0100 (CET)
Message-ID: <546D0A9D.6080209@yahoo.com>
Date: Wed, 19 Nov 2014 22:24:45 +0100
From: Quentin Lefebvre <qlefebvre_pro@yahoo.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 7bit
Subject: [dm-crypt] Empty key files vs empty passwords in plain mode
List-Id: <dm-crypt.saout.de>
List-Unsubscribe: <http://www.saout.de/mailman/options/dm-crypt>,
 <mailto:dm-crypt-request@saout.de?subject=unsubscribe>
List-Archive: <http://www.saout.de/pipermail/dm-crypt/>
List-Post: <mailto:dm-crypt@saout.de>
List-Help: <mailto:dm-crypt-request@saout.de?subject=help>
List-Subscribe: <http://www.saout.de/mailman/listinfo/dm-crypt>,
 <mailto:dm-crypt-request@saout.de?subject=subscribe>
To: dm-crypt@saout.de

Hi,

I experienced some troubles recently with Debian's cryptsetup package 
(testing version), which version is 1.6.6.
I found out that empty key files get refused by cryptsetup, for example:
cat empty_file | cryptsetup --debug --key-file=- open --type plain 
/test1.loop test1
gets rejected.
The debug output directly leads to a test in utils_crypt.c that, I 
think, should be removed.

Indeed, empty passwords are accepted, so it make sense to accept also 
empty inputs.
Especially in Debian, where cryptdisks_start script calls:
/lib/cryptsetup/askpass | cryptsetup --key-file=- open --type [type] 
[src] [dst]

What do you think about this issue?
Shall I send a patch for that?

Best regards,
Quentin

PS: I checked against the git version, the problem is not solved and 
actually exactly the same.