From owner-freebsd-geom@FreeBSD.ORG Fri Jul 16 04:22:58 2004 Return-Path: Delivered-To: freebsd-geom@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6DFD816A4CE; Fri, 16 Jul 2004 04:22:58 +0000 (GMT) Received: from maui.ebi.ac.uk (maui.ebi.ac.uk [193.62.196.100]) by mx1.FreeBSD.org (Postfix) with ESMTP id A5F0743D1D; Fri, 16 Jul 2004 04:22:56 +0000 (GMT) (envelope-from kreil@ebi.ac.uk) Received: from puffin.ebi.ac.uk (puffin.ebi.ac.uk [193.62.196.89]) by maui.ebi.ac.uk (8.11.7+Sun/8.11.7) with ESMTP id i6G4MrF27547; Fri, 16 Jul 2004 05:22:53 +0100 (BST) Received: from puffin.ebi.ac.uk (kreil@localhost) by puffin.ebi.ac.uk (8.11.6/8.11.6) with ESMTP id i6G4Mrs04821; Fri, 16 Jul 2004 05:22:53 +0100 Date: Fri, 16 Jul 2004 05:22:53 +0100 From: David Kreil Message-Id: <200407160422.i6G4Mrs04821@puffin.ebi.ac.uk> X-Mailer: exmh version 2.4 06/23/2000 with nmh-1.0.4 To: freebsd-ports@freebsd.org, freebsd-questions@freebsd.org, freebsd-fs@freebsd.org, freebsd-geom@freebsd.org X-EBI-Information: This email is scanned using www.mailscanner.info. X-EBI: Found to be clean X-EBI-SpamCheck: not spam, SpamAssassin (score=3.003, required 5, SUSPICIOUS_RECIPS 3.00) X-EBI-SpamScore: sss cc: Kreil@ebi.ac.uk Subject: "sanitizing" disks: wiping swap, non-allocated space, and file-tails X-BeenThere: freebsd-geom@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: GEOM-specific discussions and implementations List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 16 Jul 2004 04:22:58 -0000 to avoid leakage of sensitive information: any advice? X-Habeas-SWE-1: winter into spring X-Habeas-SWE-2: brightly anticipated X-Habeas-SWE-3: like Habeas SWE (tm) X-Habeas-SWE-4: Copyright 2002 Habeas (tm) X-Habeas-SWE-5: Sender Warranted Email (SWE) (tm). The sender of this X-Habeas-SWE-6: email in exchange for a license for this Habeas X-Habeas-SWE-7: warrant mark warrants that this is a Habeas Compliant X-Habeas-SWE-8: Message (HCM) and not spam. Please report use of this X-Habeas-SWE-9: mark in spam to . Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 16 Jul 2004 05:22:53 +0100 From: David Kreil Hi, (1) I was wondering whether anyone knew of packages/tools to aid in "sanitizing" a FreeBSD system, i.e., wiping + the swap slice + non-allocated space on volumes + "file-tails" (the part of the last allocated block of files not used) with random patterns to avoid leakage of sensitive information (plain text keys or decrypted texts). I am aware of the security limitations of any approach that does not involve dissolving the entire disk in acid etc but would be grateful for a pointer to a tool that at least + generates reasonably random data for its writes + ideally does a reasonable effort of turning off caching whereever it could (ideally in the file system, the disk driver, and the disk itself) or alternatively at least did the overwrites in such an order that the effect of caching would be minimized. If there are no "tools", would you know whether I can get FreeBSD on shutdown to stop using swap and access it as a raw disk device that I can write to, and how to hook into the shutdown process? (2) Related to this: I'm also interested in people's personal experiences in using partition or file system encryption options. For performance reasons I'd rather avoid having /tmp and swap and certain work space on an encrypted disk, hence the need for (1). If you feel that I'm asking this all in the wrong place, please let me know. With many thanks for your help, David. ------------------------------------------------------------------------ Dr David Philip Kreil ("`-''-/").___..--''"`-._ Research Fellow `6_ 6 ) `-. ( ).`-.__.`) University of Cambridge (_Y_.)' ._ ) `._ `. ``-..-' ++44 1223 764107, fax 333992 _..`--'_..-_/ /--'_.' ,' www.inference.phy.cam.ac.uk/dpk20 (il),-'' (li),' ((!.-' From owner-freebsd-geom@FreeBSD.ORG Fri Jul 16 07:50:29 2004 Return-Path: Delivered-To: freebsd-geom@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 9A93E16A4CE; Fri, 16 Jul 2004 07:50:29 +0000 (GMT) Received: from fw.farid-hajji.net (fw.farid-hajji.net [213.146.115.42]) by mx1.FreeBSD.org (Postfix) with ESMTP id E855243D55; Fri, 16 Jul 2004 07:50:27 +0000 (GMT) (envelope-from cpghost@cordula.ws) Received: from [192.168.254.5] (bsdevil [192.168.254.5]) by fw.farid-hajji.net (Postfix) with ESMTP id E57414AF38; Fri, 16 Jul 2004 09:50:04 +0200 (CEST) Message-ID: <40F789AA.8050403@cordula.ws> Date: Fri, 16 Jul 2004 09:54:18 +0200 From: cpghost User-Agent: Mozilla Thunderbird 0.7.1 (X11/20040709) X-Accept-Language: en-us, en MIME-Version: 1.0 To: David Kreil References: <200407160422.i6G4Mrs04821@puffin.ebi.ac.uk> In-Reply-To: <200407160422.i6G4Mrs04821@puffin.ebi.ac.uk> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit cc: freebsd-questions@freebsd.org cc: freebsd-geom@freebsd.org Subject: Re: "sanitizing" disks: wiping swap, non-allocated space, and file-tails X-BeenThere: freebsd-geom@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: GEOM-specific discussions and implementations List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 16 Jul 2004 07:50:29 -0000 David Kreil wrote: >I'm also interested in people's personal experiences in using partition or >file system encryption options. > > gbde(1) works fine for me, even for swap and /tmp. The only problem is that you can't reboot without operator assistance to enter the passphrase(s). >David. > > -cpghost. -- Cordula's Web. http://www.cordula.ws/