From owner-freebsd-security Thu Nov 18 21:29:28 1999 Delivered-To: freebsd-security@freebsd.org Received: from ind.alcatel.com (postal.xylan.com [208.8.0.248]) by hub.freebsd.org (Postfix) with ESMTP id 7A64F14D4B; Thu, 18 Nov 1999 21:29:25 -0800 (PST) (envelope-from wes@softweyr.com) Received: from mailhub.xylan.com (mailhub [198.206.181.70]) by ind.alcatel.com (8.9.3+Sun/8.9.1 (ind.alcatel.com 3.0 [OUT])) with SMTP id VAA26327; Thu, 18 Nov 1999 21:25:06 -0800 (PST) X-Origination-Site: Received: from omni.xylan.com by mailhub.xylan.com (SMI-8.6/SMI-SVR4 (mailhub 2.1 [HUB])) id VAA00322; Thu, 18 Nov 1999 21:25:05 -0800 Received: from softweyr.com ([204.68.178.39]) by omni.xylan.com (4.1/SMI-4.1 (xylan engr [SPOOL])) id AA16734; Thu, 18 Nov 99 21:24:52 PST Message-Id: <3834DF23.3416C163@softweyr.com> Date: Thu, 18 Nov 1999 22:24:51 -0700 From: Wes Peters Organization: Softweyr LLC X-Mailer: Mozilla 4.7 [en] (X11; U; FreeBSD 3.1-RELEASE i386) X-Accept-Language: en Mime-Version: 1.0 To: Jonathon McKitrick Cc: peter.jeremy@alcatel.com.au, TrouBle , security@FreeBSD.ORG, questions@FreeBSD.ORG Subject: Re: secure filesystem wiping References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Jonathon McKitrick wrote: > > On Fri, 19 Nov 1999, Peter Jeremy wrote: > > >This isn't technically possible. You can't securely wipe data from a > >disk using the disks own R/W head/electronics (which is the only way > >to preserve intact files). > > Why isn't it possible to read unallocated sectors and write back sectors > full of garbage, or 0xFF? It is, but that won't erase the disk, at least not well enough that someone who knows what they're doing can't get it back. -- "Where am I, and what am I doing in this handbasket?" Wes Peters Softweyr LLC wes@softweyr.com http://softweyr.com/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message