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,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 6ABE4ECDE5F for ; Thu, 19 Jul 2018 14:59:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2E6CB20673 for ; Thu, 19 Jul 2018 14:59:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2E6CB20673 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.com 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 S1731796AbeGSPmi (ORCPT ); Thu, 19 Jul 2018 11:42:38 -0400 Received: from smtp.nue.novell.com ([195.135.221.5]:59647 "EHLO smtp.nue.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730919AbeGSPmh (ORCPT ); Thu, 19 Jul 2018 11:42:37 -0400 Received: from linux-l9pv.suse (124-11-22-254.static.tfn.net.tw [124.11.22.254]) by smtp.nue.novell.com with ESMTP (TLS encrypted); Thu, 19 Jul 2018 16:58:57 +0200 Date: Thu, 19 Jul 2018 22:58:47 +0800 From: joeyli To: Pavel Machek Cc: Yu Chen , "Rafael J . Wysocki" , Eric Biggers , 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: <20180719145847.GJ18419@linux-l9pv.suse> References: <20180718202235.GA4132@amd> <20180718235851.GA22170@sandybridge-desktop> <20180719110149.GA4679@amd> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180719110149.GA4679@amd> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Thu, Jul 19, 2018 at 01:01:49PM +0200, Pavel Machek wrote: > On Thu 2018-07-19 07:58:51, Yu Chen wrote: > > Hi, > > On Wed, Jul 18, 2018 at 10:22:35PM +0200, Pavel Machek wrote: > > > On Thu 2018-07-19 00:38:06, Chen Yu wrote: > > > > As security becomes more and more important, we add the in-kernel > > > > encryption support for hibernation. > > > > > > Sorry, this does not really explain what security benefit it is > > > supposed have to against what attack scenarios. > > > > > > Which unfortunately means it can not reviewed. > > > > > > Note that uswsusp already provides encryption. If this is supposed to > > > have advantages over it, please say so. > > > > > The advantages are described in detail in > > [PATCH 1/4]'s log, please refer to that. > > Are you refering to this? > > # Generally the advantage is: Users do not have to > # encrypt the whole swap partition as other tools. > # After all, ideally kernel memory should be encrypted > # by the kernel itself. > > Sorry, this does not really explain what security benefit it is > supposed have to against what attack scenarios. > > Note that uswsusp already provides encryption. If this is supposed to > have advantages over it, please say so. > > Also note that joeyli has patch series which encrypts > both in-kernel and uswsusp hibernation methods. His motivation is > secure boot. How does this compare to his work? > My patchset signs and encrypts the snapshot image pages in memory. The main logic is applied to snapshot.c https://github.com/joeyli/linux-s4sign/commit/bae39460393ada4c0226dd07cd5e3afcef86b71f The pros of my solution is that the signed/encrypted snapshot image can be stored to anywhere. Both in-kernel and userspace. Yu's patch is encrypt the page buffer before sending to block io layer for writing to swap. The main logic is applied to swap.c. It's against the swap solution in-kernel. The pros of Yu's solution is that it encrypts the compressed image data. So, for the huge system memory case, it has better performance. Yu's plan is using the sysfs to switch different encrypt/sign solutions. And, we will share encrypt/sign helper and key manager in the above two solutions. Thanks a lot! Joey Lee