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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 20D19C2D0DB for ; Tue, 28 Jan 2020 17:35:45 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id E0880214AF for ; Tue, 28 Jan 2020 17:35:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="DE11XLIL" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E0880214AF Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:34464 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iwUm8-0000wy-3d for qemu-devel@archiver.kernel.org; Tue, 28 Jan 2020 12:35:44 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:54078) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iwUjg-0006fw-M6 for qemu-devel@nongnu.org; Tue, 28 Jan 2020 12:33:14 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iwUje-0002mS-7h for qemu-devel@nongnu.org; Tue, 28 Jan 2020 12:33:12 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:25098 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iwUja-0002h4-1B for qemu-devel@nongnu.org; Tue, 28 Jan 2020 12:33:06 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1580232783; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=sKs91koXvRHhuchystOq4ZoZQfcupWaFG38wVLLiB6g=; b=DE11XLILEx0QvWBTg6j9PClNPznQ37vvHvKVx9bRB2PMhDQbr8xxfSSBdKA2NhgXMGkH0E kS0HILCm3Vi5rvzVqrrSA9Jzrn6pTb2dO04DXFj8lCEPBkmIrPJ7jncnLj4Ve+61INl+Tx n+jA6UEE6ROdu6nLfJl7qYxrxPr811E= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-81-DzjmXy4pOOKsaEas3kOYvA-1; Tue, 28 Jan 2020 12:33:01 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3716013E5; Tue, 28 Jan 2020 17:33:00 +0000 (UTC) Received: from redhat.com (ovpn-112-34.ams2.redhat.com [10.36.112.34]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 3F76480A5C; Tue, 28 Jan 2020 17:32:54 +0000 (UTC) Date: Tue, 28 Jan 2020 17:32:51 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Maxim Levitsky Subject: Re: [PATCH 02/13] qcrypto-luks: implement encryption key management Message-ID: <20200128173251.GZ1446339@redhat.com> References: <20200114193350.10830-1-mlevitsk@redhat.com> <20200114193350.10830-3-mlevitsk@redhat.com> <87r1zti6r8.fsf@dusky.pond.sub.org> <20200128171116.GU1446339@redhat.com> MIME-Version: 1.0 In-Reply-To: <20200128171116.GU1446339@redhat.com> User-Agent: Mutt/1.13.3 (2020-01-12) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: DzjmXy4pOOKsaEas3kOYvA-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 207.211.31.120 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: Kevin Wolf , qemu-block@nongnu.org, Markus Armbruster , qemu-devel@nongnu.org, Max Reitz , John Snow Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, Jan 28, 2020 at 05:11:16PM +0000, Daniel P. Berrang=C3=A9 wrote: > On Tue, Jan 21, 2020 at 03:13:01PM +0200, Maxim Levitsky wrote: > > On Tue, 2020-01-21 at 08:54 +0100, Markus Armbruster wrote: > >=20 > > > >=20 > > > > +## > > > > +# @LUKSKeyslotUpdate: > > > > +# > > > > +# @keyslot: If specified, will update only keyslot with th= is index > > > > +# > > > > +# @old-secret: If specified, will only update keyslots that > > > > +# can be opened with password which is contained= in > > > > +# QCryptoSecret with @old-secret ID > > > > +# > > > > +# If neither @keyslot nor @old-secret is specifi= ed, > > > > +# first empty keyslot is selected for the update > > > > +# > > > > +# @new-secret: The ID of a QCryptoSecret object providing a n= ew decryption > > > > +# key to place in all matching keyslots. > > > > +# null/empty string erases all matching keyslots > > >=20 > > > I hate making the empty string do something completely different than= a > > > non-empty string. > > >=20 > > > What about making @new-secret optional, and have absent @new-secret > > > erase? > >=20 > > I don't remember already why I and Keven Wolf decided to do this this w= ay, but I think that you are right here. > > I don't mind personally to do this this way. > > empty string though is my addition, since its not possible to pass null= on command line. >=20 > IIUC this a result of using "StrOrNull" for this one field... >=20 >=20 > > > > +# Since: 5.0 > > > > +## > > > > +{ 'struct': 'LUKSKeyslotUpdate', > > > > + 'data': { > > > > + '*keyslot': 'int', > > > > + '*old-secret': 'str', > > > > + 'new-secret' : 'StrOrNull', > > > > + '*iter-time' : 'int' } } >=20 > It looks wierd here to be special casing "new-secret" to "StrOrNull" > instead of just marking it as an optional string field >=20 > "*new-secret": "str" >=20 > which would be possible to use from the command line, as you simply > omit the field. >=20 > I guess the main danger here is that we're using this as a trigger > to erase keyslots. So simply omitting "new-secret" can result > in damage to the volume by accident which is not an attractive > mode. Thinking about this again, I really believe we ought to be moire explicit about disabling the keyslot by having the "active" field. eg { 'struct': 'LUKSKeyslotUpdate', 'data': { 'active': 'bool', '*keyslot': 'int', '*old-secret': 'str', '*new-secret' : 'str', '*iter-time' : 'int' } } "new-secret" is thus only needed when "active" =3D=3D true. This avoids the problem with being unable to specify a null for StrOrNull on the command line too. Regards, Daniel --=20 |: 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= :|