From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.saout.de ([127.0.0.1]) by localhost (mail.saout.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id qqTcE2GXlH76 for ; Thu, 16 Jan 2014 22:36:24 +0100 (CET) Received: from awesome.dsw2k3.info (unknown [IPv6:2a01:198:661:1f::3]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.saout.de (Postfix) with ESMTPS for ; Thu, 16 Jan 2014 22:36:24 +0100 (CET) Date: Thu, 16 Jan 2014 22:36:19 +0100 From: Matthias Schniedermeyer Message-ID: <20140116213619.GA19498@citd.de> References: <638F1A81-8F17-4E18-8993-7F848EA84F08@offensive-security.com> <20140114043042.GA15870@tansi.org> <52D6EF1B.4020206@gmail.com> <52D7AB5E.8020302@redhat.com> <52D833F1.5010205@gmail.com> <52D83D00.50402@riseup.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <52D83D00.50402@riseup.net> Subject: Re: [dm-crypt] nuke password to delete luks header List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Iggy Cc: dm-crypt@saout.de On 16.01.2014 15:11, Iggy wrote: > > > PS: An interesting, but only marginally helpful, byproduct of such a > feature is that on the off-chance that an adversary were attempting to > brute-force the password on their only copy of a volume (this is the > unlikely bit), and the nuke password had less entropy than the > decryption passphrase, then there is a chance the adversary themselves > would remove access to the data, without intervention from the target of > the attack, by accidentally brute-forcing the nuke password. You wouldn't brute force using the actual system, much too slow. You make a copy and brute force the data with something that allows as much key/s as possible. Which means you can't use the actual system. That also means the system that is actually used to do the brute-forcing won't implement the "nuke" capability (Assuming at least some competence on the attacker side) but may include code determine that it is a nuke key, because there has to be a way to identify that status at least after you found the correct passwort. Otherwise the feature would simply be impossible to implement. -- Matthias