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 5laaBz3arEwO for ; Fri, 24 Aug 2012 17:59:41 +0200 (CEST) Received: from gerolde.archlinux.org (gerolde.archlinux.org [66.211.214.132]) by mail.saout.de (Postfix) with ESMTP for ; Fri, 24 Aug 2012 17:59:41 +0200 (CEST) Received: from [134.61.65.222] (65-222.eduroam.rwth-aachen.de [134.61.65.222]) by gerolde.archlinux.org (Postfix) with ESMTPSA id CE1459200C for ; Fri, 24 Aug 2012 11:58:42 -0400 (EDT) Message-ID: <5037A4EB.2080201@archlinux.org> Date: Fri, 24 Aug 2012 17:59:39 +0200 From: =?ISO-8859-15?Q?Thomas_B=E4chler?= MIME-Version: 1.0 References: <50379888.7060202@redhat.com> <50379C59.5020908@archlinux.org> <20120824155405.GC30694@tansi.org> In-Reply-To: <20120824155405.GC30694@tansi.org> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="------------enig02EF7E4B9D6501A566625DBC" Subject: Re: [dm-crypt] SSDs & flash... and secure keyslot erase List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: dm-crypt@saout.de This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig02EF7E4B9D6501A566625DBC Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: quoted-printable Am 24.08.2012 17:54, schrieb Arno Wagner: > On Fri, Aug 24, 2012 at 05:23:05PM +0200, Thomas B?chler wrote: >> Am 24.08.2012 17:06, schrieb Milan Broz: > [...] >>> But there is no perfect solution. >> >> Interesting write-up. If you are really paranoid, it seems you must ba= ck >> up all data, perform ATA security erase and put the data back on the >> disk (and then perform ATA security erase on the backup). >=20 > That may not be enough, see Section 3.2 of=20 >=20 > http://cseweb.ucsd.edu/users/swanson/papers/Fast2011SecErase.pdf >=20 > Unfortunately, no manufacturer names given. >=20 > My current take is that the only reliable thing is to have LUKS > key-slots individually larger than the spare area and then overwrite > all free space with random data after a key-slot change. That way > the SSD would be unable to hold an old key-slot. For a 240G > SSD that may mean key-slots > 16GB each. Also, you cannot be > sure how much Flash capacity an SSD actually has without=20 > opening it.=20 Okay then. If you are paranoid, burn the entire SSD if your passphrase is corrupted. --------------enig02EF7E4B9D6501A566625DBC Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBCAAGBQJQN6TrAAoJEChPw0yOSxolhcUP+gNUAEaEY01GwG0eDdUT9VbS uVqrVamaxzK/Sg+mmolUzgjIhcfhUrU/Lv/D3us9Xl00icBVgkqVV/A4dEzcRi34 +UYaM4EAfOBObdHBXfx94YuB/xYOqCA8fC+aieIFhx3e9WCA3gY1583RdHVNdw2y v//i4gqbK+OC/XKjER0C8GVdnJBAU1Nl4oY3e228RA8KL+K04KRWhiCdcqu0CS0V Mpknlb20BcRdtK4JlwUMmTchJRv5RfPZPF84N0nTzsZ8OIbZb1sMyScmzj2XFwBK L9YM6Wzc3v9OEsgkO6OgCTTrD+//gzTW8mi6aa846ZEYDPDBznLmtQ6Uc0wBl96J Zu+rafzBRCx+XWe6wA1e99+SPbJc5bRodSTKPUqIBHOiydI+ANTf1kfuN1xAEAjA p6GSRxUwud69dke1C1yteZ8mjcJ2p9eDm6Fm+HMtwYIk8cIl0YftZcd5aLXeAFZ2 kXlKOkpr6nOoCfnzypIFvujhv+OD/4cZWUsZrZDnPV4ly6PheIeQGtQjN1U8r8Gg g16DiZjEbCDUcp06qgFm+kEM4MokdFtifcN3rNfWOT2ELlYr8n9MiL/mRboPrHEB zN02yWzjc/RJR5hLGDUZFHPArMfVlodHhEckIm2PVuCCAxqpLTOftoaS7riqx0Ov +bvlTLI98tPfQVJgpq4D =TMLY -----END PGP SIGNATURE----- --------------enig02EF7E4B9D6501A566625DBC--