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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 34BD8C4332F for ; Wed, 16 Nov 2022 11:15:51 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ovGO4-0004zL-1h; Wed, 16 Nov 2022 06:15:24 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ovGO2-0004z2-3I for qemu-devel@nongnu.org; Wed, 16 Nov 2022 06:15:22 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ovGO0-0004iR-Dc for qemu-devel@nongnu.org; Wed, 16 Nov 2022 06:15:21 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1668597319; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=s1u7F3AALR0mkUUQUhPUq/G+IXRWSOEZhUmS0ypflS0=; b=N0i4Ov/oevwxObwL0FlVq2aZONMnAd5KbjoQB/VJZhXJOibP0DJrpxvop+1nMOVYjdFqUe kG8LRmrc1YLYIHtszho9KYqVg11PBjCjPBdNjMyLlcQoqxV92CrsV0H/BPLExzhRuylKGQ om3+xWxtJvWNQX6gXPbQ93MXT1zHA6w= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-410-qmaa5Y8nP1uR4C3_vT-yag-1; Wed, 16 Nov 2022 06:15:14 -0500 X-MC-Unique: qmaa5Y8nP1uR4C3_vT-yag-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C8923833AEC; Wed, 16 Nov 2022 11:15:13 +0000 (UTC) Received: from redhat.com (unknown [10.33.36.81]) by smtp.corp.redhat.com (Postfix) with ESMTPS id BD9061121325; Wed, 16 Nov 2022 11:15:12 +0000 (UTC) Date: Wed, 16 Nov 2022 11:15:07 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Or Ozeri , "qemu-devel@nongnu.org" , "qemu-block@nongnu.org" , Danny Harnik , "idryomov@gmail.com" Subject: Re: [PATCH v3] block/rbd: Add support for layered encryption Message-ID: References: <20221115122527.2896476-1-oro@il.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/2.2.7 (2022-08-07) X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Wed, Nov 16, 2022 at 10:23:52AM +0000, Daniel P. Berrangé wrote: > On Wed, Nov 16, 2022 at 09:03:31AM +0000, Or Ozeri wrote: > > > -----Original Message----- > > > From: Daniel P. Berrangé > > > Sent: 15 November 2022 19:47 > > > To: Or Ozeri > > > Cc: qemu-devel@nongnu.org; qemu-block@nongnu.org; Danny Harnik > > > ; idryomov@gmail.com > > > Subject: [EXTERNAL] Re: [PATCH v3] block/rbd: Add support for layered > > > encryption > > > > > > AFAICT, supporting layered encryption shouldn't require anything other than > > > the 'parent' addition. > > > > > > > Since the layered encryption API is new in librbd, we don't have to > > support "luks" and "luks2" at all. > > In librbd we are actually deprecating the use of "luks" and "luks2", > > and instead ask users to use "luks-any". > > Deprecating that is a bad idea. The security characteristics and > feature set of LUKSv1 and LUKSv2 can be quite different. If a mgmt > app is expecting the volume to be protected with LUKSv2, it should > be stating that explicitly and not permit a silent downgrade if > the volume was unexpectedly using LUKSv1. > > > If we don't add "luks-any" here, we will need to implement > > explicit cases for "luks" and "luks2" in the qemu_rbd_encryption_load2. > > This looks like a kind of wasteful coding that won't be actually used > > by users of the rbd driver in qemu. > > It isn't wasteful - supporting the formats explicitly is desirable > to prevent format downgrades. > > > Anyhow, we need the "luks-any" option for our use-case, so if you > > insist, I will first submit a patch to add "luks-any", before this > > patch. > > I'm pretty wary of any kind of automatic encryption format detection > in QEMU. The automatic block driver format probing has been a long > standing source of CVEs in QEMU and every single mgmt app above QEMU. Having said that, normal linux LUKS tools like cryptsetup or systemd LUKS integration will auto-detect luks1 vs luks2. All cryptsetup commands also have an option to explicitly specify the format version. So with that precedent I guess it is ok to add 'luks-any'. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|