From owner-freebsd-security Wed May 19 21:25:33 1999 Delivered-To: freebsd-security@freebsd.org Received: from xylan.com (postal.xylan.com [208.8.0.248]) by hub.freebsd.org (Postfix) with ESMTP id F3B0B14E1B for ; Wed, 19 May 1999 21:25:31 -0700 (PDT) (envelope-from wes@softweyr.com) Received: from mailhub.xylan.com by xylan.com (8.8.7/SMI-SVR4 (xylan-mgw 2.2 [OUT])) id VAA04682; Wed, 19 May 1999 21:23:48 -0700 (PDT) Received: from omni.xylan.com by mailhub.xylan.com (SMI-8.6/SMI-SVR4 (mailhub 2.1 [HUB])) id VAA06832; Wed, 19 May 1999 21:23:48 -0700 Received: from softweyr.com ([204.68.178.39]) by omni.xylan.com (4.1/SMI-4.1 (xylan engr [SPOOL])) id AA19650; Wed, 19 May 99 21:23:41 PDT Message-Id: <37438E4C.4B95B937@softweyr.com> Date: Wed, 19 May 1999 22:23:40 -0600 From: Wes Peters Organization: Softweyr LLC X-Mailer: Mozilla 4.5 [en] (X11; U; FreeBSD 3.1-RELEASE i386) X-Accept-Language: en Mime-Version: 1.0 To: Warner Losh Cc: "Ilmar S. Habibulin" , posix1e@cyrus.watson.org, freebsd-security@FreeBSD.ORG Subject: Re: secure deletion References: <199905192041.OAA01463@harmony.village.org> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Warner Losh wrote: > > In message "Ilmar S. Habibulin" writes: > : May be it's an freebsd-fs@ question, but i think that it belings here to. > : I heard that some linux fs (maybe extfs2?) have some secure deletion flag, > : which being set on inode(file or dir) cause content of this file to be > : wiped before deletion, so even if somebody manage to restore file, its > : content would be unusable. I think, that it is nice feature, and i would > : like to see it in freebsd. What would you say? > : > : PS. I have implementation of this feature for freebsd-2.2.5. May be i can > : port it to 3.x. > > Does it doe the DoD recommended patter of deletion? That is overwrite > the blocks with sever different series of bit patterns to make it > impossible to recover using the usual techniques, or is it just a > bzero of the blocks in question? The former is secure deletion, the > latter is too insecure for most people that want this feature... The standard used to be 100 overwrites of 0xe5 then 0x5e, but they changed the standard just as I was leaving the defense industry in 1991. Does Posix or SUS have anything to say about this? -- "Where am I, and what am I doing in this handbasket?" Wes Peters Softweyr LLC http://www.softweyr.com/~softweyr wes@softweyr.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message