From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from maude.comedia.it (mail.comedia.it [77.93.254.181]) (using TLSv1 with cipher ADH-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by mail.saout.de (Postfix) with ESMTPS for ; Thu, 3 Jun 2010 22:48:24 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by maude.comedia.it (Postfix) with ESMTP id 50FAA86F2B for ; Thu, 3 Jun 2010 22:48:23 +0200 (CEST) Received: from maude.comedia.it ([127.0.0.1]) by localhost (maude.comedia.it [127.0.0.1]) (amavisd-new, port 10025) with LMTP id BPKK7rHHXqfD for ; Thu, 3 Jun 2010 22:48:18 +0200 (CEST) Date: Thu, 3 Jun 2010 22:48:18 +0200 From: Luca Berra Message-ID: <20100603204818.GC26862@maude.comedia.it> References: <4C07CF68.7090708@redhat.com> <20100603201452.GA10428@tansi.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Disposition: inline In-Reply-To: <20100603201452.GA10428@tansi.org> Subject: Re: [dm-crypt] Corrupted luks partition, help needed List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: dm-crypt@saout.de On Thu, Jun 03, 2010 at 10:14:53PM +0200, Arno Wagner wrote: >On Thu, Jun 03, 2010 at 09:05:59PM +0300, Panagiotis Malakoudis wrote: >> OK, I looked a bit more inside LUKS specification and I now know that the >> 128KB keyslot is actually the 32byte master key AF-split to 128KB and then >> encoded with my key. A single bit of change in these 128KB makes key >> invalid. >> >> Now that I know all this, I consider the LUKS format fundamentally flawed to >> data corruption. > >It is. However this area should not be written by anything except >cryoptsetup. If you look closely basically every filesystem >and partition scheme is about as vulnerable. The thing is, >modern disks do not suffer single bit corruption easily. More >likely are whole lost sectors. well, actually if you look closely at modern filesystems and partitioning schemes, you will find there are more than one copy of critical metadata. ext2 has a backup superblock GPT partition has a secondary header and table at the other end of the disk we really miss an on-disk backup of the LUKS header. L. -- Luca Berra -- bluca@comedia.it Communication Media & Services S.r.l. /"\ \ / ASCII RIBBON CAMPAIGN X AGAINST HTML MAIL / \