From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from plane.gmane.org (plane.gmane.org [80.91.229.3]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.server123.net (Postfix) with ESMTPS for ; Fri, 6 Feb 2015 15:47:49 +0100 (CET) Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1YJkCC-0004Vb-Hg for dm-crypt@saout.de; Fri, 06 Feb 2015 15:47:48 +0100 Received: from ip4d151e07.dynamic.kabel-deutschland.de ([77.21.30.7]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 06 Feb 2015 15:47:48 +0100 Received: from for-gmane by ip4d151e07.dynamic.kabel-deutschland.de with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 06 Feb 2015 15:47:48 +0100 From: "U.Mutlu" Date: Fri, 06 Feb 2015 15:47:41 +0100 Message-ID: References: <54D21872.2030406@yahoo.com> <20150205115435.GA4093@tansi.org> <20150205235135.GA21304@tansi.org> <20150206140140.GA16920@dashborg.com> <20150206141922.Horde.DBddy8_J-Ko1WZpcZHQHTQ8@skrilnetz.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit In-Reply-To: <20150206141922.Horde.DBddy8_J-Ko1WZpcZHQHTQ8@skrilnetz.net> Subject: Re: [dm-crypt] plain: opening with a wrong password List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: dm-crypt@saout.de Michael wrote, On 02/06/2015 03:19 PM: > If you are concerned about the header, you could use Luks with a detached > header. This way you have the advantages of Luks and you can store the header > separate from the encrypted container. Beware: there are some warnings in the documentation @ https://code.google.com/p/cryptsetup/wiki/Cryptsetup140 " WARNING: There is no possible check that specified ciphertext device matches detached on-disk header. Use with care, it can destroy your data in case of a mistake. WARNING: Storing LUKS header in a file means that anti-forensic splitter cannot properly work (there is filesystem allocation layer between header and disk)." cu Uenal > Quoting dennis@basis.uklinux.net: > >> On Fri, Feb 06, 2015 at 12:51:35AM +0100, Arno Wagner wrote: >>> If your passphrase is weak enough that a dictionary >>> attack has a reasonable success of working (and a dictionary >>> attack is the only thing the salt that hashalot adds helps >>> against), then you are pretty deep in insecure territory and >>> _need_ the hash iteration that LUKS provides, but which is >>> missing from both plain and hashalot. >>> >>> ... >>> >>> Please do not spread unsubstantiated rumors. It is hard enough >>> these days for non-experts to decide what crypto to trust >>> and what not. Rumors of the kind "metadata headers offer >>> attack vectors" make this even worse. >> >> Count me among the non-experts. I have two questions. (a) Wouldn't >> metadata headers incur a loss of plausible deniablity compared to >> plain mode, especially when an encrypted filesystem image is stored as >> a single file on backup media or in the backing file for a loopback >> device? (b) Assuming a secure passphrase, wouldn't plain mode be more >> secure than luks against possible vulnerabilities in the hashing >> algorithm that may be discovered in the future? >> _______________________________________________