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 bll9NdEvDKJe for ; Sat, 5 Jan 2013 20:47:14 +0100 (CET) Received: from v4.tansi.org (ns.km33513-03.keymachine.de [87.118.94.3]) by mail.saout.de (Postfix) with ESMTP for ; Sat, 5 Jan 2013 20:47:14 +0100 (CET) Received: from gatewagner.dyndns.org (84-74-164-49.dclient.hispeed.ch [84.74.164.49]) by v4.tansi.org (Postfix) with ESMTPA id 8BCC02067E5 for ; Sat, 5 Jan 2013 20:47:14 +0100 (CET) Date: Sat, 5 Jan 2013 20:47:14 +0100 From: Arno Wagner Message-ID: <20130105194714.GA3583@tansi.org> References: <50E6C1EC.1000307@gmail.com> <50E6C2B6.30505@ramses-pyramidenbau.de> <50E6C899.2060407@gmail.com> <20130104162652.GB22218@tansi.org> <20130104202025.GA23856@fancy-poultry.org> <50E741FB.6050000@gmail.com> <20130104220526.GB23626@tansi.org> <50E75A2F.4090102@gmail.com> <20130105172034.GA2859@tansi.org> <50E87030.3070004@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <50E87030.3070004@gmail.com> Subject: Re: [dm-crypt] Switch to XTS mode for LUKS in cryptsetup in 1.6.0 (Was Re: [ANNOUNCE] cryptsetup 1.6.0-rc1) List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: dm-crypt@saout.de On Sat, Jan 05, 2013 at 07:25:52PM +0100, Milan Broz wrote: > On 01/05/2013 06:20 PM, Arno Wagner wrote: > > > What does RHEL use and recommend? Do they always use > > AES256-XTS or is AES128-XTS offered as an option (not when > > douing this manually via commandline). I think there would > > be some benefit to have the same defauls in distro-independent > > cryptsetup. > > - Encrypted disk installation is using AES-XTS with 512bit key. > (installer overwrites default. But I know there was no > real discussion about AES18/256 before this was changed.) Always nice to know what happens begind the curtains ;-) > Installed (anaconda) doesn't allow default cipher/key size change > but allows to "reuse" existing LUKS device. > > - compiled-in cryptsetup default is the same as upstream (CBC with ESSIV) > (RHEL7 will use XTS as default, I would like to see the same > default as upstream.) > (This was mainly for compatibility reasons but now even RHEL5 can > map XTS LUKS discs.) > > - RHEL in FIPS mode (dmcrypt/LUKS module is still not validated though) > allows CBC (only with ESSIV) and XTS with AES128/192/256 > > Well, I can get more info from independent people here internally. > > My current opinion is to use aes-xts-plain64 with 256bit key > (IOW use AES128) as independent default for LUKS. I think that is probably the best option at the moment. Arno -- Arno Wagner, Dr. sc. techn., Dipl. Inform., Email: arno@wagner.name GnuPG: ID: CB5D9718 FP: 12D6 C03B 1B30 33BB 13CF B774 E35C 5FA1 CB5D 9718 ---- One of the painful things about our time is that those who feel certainty are stupid, and those with any imagination and understanding are filled with doubt and indecision. -- Bertrand Russell