From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3F83FC6778A for ; Tue, 24 Jul 2018 13:03:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E775120874 for ; Tue, 24 Jul 2018 13:03:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E775120874 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ucw.cz Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388332AbeGXOKO (ORCPT ); Tue, 24 Jul 2018 10:10:14 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:53661 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388279AbeGXOKO (ORCPT ); Tue, 24 Jul 2018 10:10:14 -0400 Received: by atrey.karlin.mff.cuni.cz (Postfix, from userid 512) id B7CC98055A; Tue, 24 Jul 2018 15:03:47 +0200 (CEST) Date: Tue, 24 Jul 2018 15:03:46 +0200 From: Pavel Machek To: Oliver Neukum Cc: Yu Chen , "Rafael J . Wysocki" , Eric Biggers , "Lee, Chun-Yi" , Theodore Ts o , Stephan Mueller , Denis Kenzior , linux-pm@vger.kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, "Gu, Kookoo" , "Zhang, Rui" Subject: Re: [PATCH 0/4][RFC v2] Introduce the in-kernel hibernation encryption Message-ID: <20180724130110.GA29006@amd> References: <20180718202235.GA4132@amd> <20180718235851.GA22170@sandybridge-desktop> <20180719110149.GA4679@amd> <20180719132003.GA30981@sandybridge-desktop> <20180720102532.GA20284@amd> <1532346156.3057.11.camel@suse.com> <20180723162302.GA4503@sandybridge-desktop> <20180724120133.GD26036@amd> <1532436474.17797.20.camel@suse.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="oC1+HKm2/end4ao3" Content-Disposition: inline In-Reply-To: <1532436474.17797.20.camel@suse.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --oC1+HKm2/end4ao3 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue 2018-07-24 14:47:54, Oliver Neukum wrote: > On Di, 2018-07-24 at 14:01 +0200, Pavel Machek wrote: > > Hi! > >=20 > > > > > > "There have some functions be locked-down because > > > > > > there have no appropriate mechanisms to check the > > > > > > integrity of writing data." > > > > > > https://patchwork.kernel.org/patch/10476751/ > > > > >=20 > > > > > So your goal is to make hibernation compatible with kernel > > > > > lockdown? Do your patches provide sufficient security that hibern= ation > > > > > can be enabled with kernel lockdown? > > > >=20 > > > > OK, maybe I am dense, but if the key comes from user space, will th= at > > > > be enough? > > > >=20 > > >=20 > > > Good point, we once tried to generate key in kernel, but people > > > suggest to generate key in userspace and provide it to the > > > kernel, which is what ecryptfs do currently, so it seems this > > > should also be safe for encryption in kernel. > >=20 > > Safe against what kind of attack? Please describe what kind of > > security you are trying to provide. >=20 > Unsigned code must not take over the priviledge level of signed code. > Hence: >=20 > 1. Unsigned code must not allowed to read sensitive parts of signed > code's memory space >=20 > 2. Unsigned code must not be able to alter the memory space of > signed code -> snapshots that are changed must not be able to be > resumed Ok. > > I don't think generating key in userspace is good enough for providing > > guarantees for secure-boot. >=20 > Why? Because then, userpace has both key (now) and encrypted image (after reboot), so it can decrypt, modify, re-encrypt...? Pavel --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --oC1+HKm2/end4ao3 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAltXI7IACgkQMOfwapXb+vK8JwCfeZUQh+2gddlW14jEDIAOd7bG keQAoIysDM0pDoo0PllRmxnnEFrNOo38 =CdfA -----END PGP SIGNATURE----- --oC1+HKm2/end4ao3--