From nobody Wed Dec 19 08:46:35 2018 Return-Path: X-Original-To: perc@ietfa.amsl.com Delivered-To: perc@ietfa.amsl.com Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 99273130E72 for ; Wed, 19 Dec 2018 08:46:33 -0800 (PST) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -1.9 X-Spam-Level: X-Spam-Status: No, score=-1.9 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIMWL_WL_MED=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_NONE=-0.0001] autolearn=ham autolearn_force=no Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=ipv-sx.20150623.gappssmtp.com Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 6dwcqV7Si2Xo for ; Wed, 19 Dec 2018 08:46:31 -0800 (PST) Received: from mail-oi1-x22a.google.com (mail-oi1-x22a.google.com [IPv6:2607:f8b0:4864:20::22a]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 28A64130E66 for ; Wed, 19 Dec 2018 08:46:31 -0800 (PST) Received: by mail-oi1-x22a.google.com with SMTP id y1so2105685oie.12 for ; Wed, 19 Dec 2018 08:46:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ipv-sx.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=I3u6mLJornVp892qxN8nho/OuipTGdMhXdPEFAPhzOo=; b=ZvLfQuOX836jpqSEc2rGh1E6/9ACKyRjI6S2VZ5tcedNkR4Qq+0pjuTZPcX9AXuTtD LdtXtSkrg7PALRUp2TNT6XREr00YXl+6Mex73syaJULWD5Wu3i4ezcW7gFt31bHgyuT2 jceuT6qRylQaP3DfxWcmurxR7Wl1OwK/QvLMQe+L0bKgCkUHrrX0elsV7dBOT93+UF1x auHbSe67MLug+4mmZ72SivocNJJDMGUZW79Y8/s/q96/e0gUQIkBkSxGdgo210hTMThi vfchCrwjzIS+axPONAPd5s1KB2xdkoXwLt776alLFgUBmlUcHx7miZpdKFk+rBXoVb9Y drng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=I3u6mLJornVp892qxN8nho/OuipTGdMhXdPEFAPhzOo=; b=jFVhU8LyDYqODHL4+t36pPjraxhOv/4GNhU429mTqAmjGlMhl51goL1o1ymLq1v81h jb4uNc/6HzvkfllNwMq1xX14glNFH32CXt+7VlQeUzQthcFqs8sv1Un9QnyxJaWOGAhi 1kDafClvi5oP/9nU06CrgX/R1Cs3uOYx5cTvx1epPa4hgoKVfF+iqJHATaH0407a8OQI T/H15hfal2F773hOc2qN7fVh92W8TRwNsBRjkc5QBeCM5yTXXOJcFVS04AWvIcqcuOy3 5kVwNExOjwZ6IXEmXOaNcysBeX7G8lv47296M/FFy5qgo0F6Euien28qO60smG26HdI7 mA0Q== X-Gm-Message-State: AA+aEWaGv1T2DGpxPSwjVyBaOZrwLHb4R8m30DtqonEu1axUR/qafhib 236kT+tVpl40hyBrkmCgSPxMDJZjTIlqOetbAzz61A== X-Google-Smtp-Source: AFSGD/UY5Ba5rc/1197zcxCB6aENtbS5nwqhcZNLkPjJ4XGKRDrwomNcb2U/OOuLhtcQAwOQRUOF8nSbYfYYafIs/Ig= X-Received: by 2002:aca:d64d:: with SMTP id n74mr1480723oig.199.1545237987469; Wed, 19 Dec 2018 08:46:27 -0800 (PST) MIME-Version: 1.0 References: <154002385712.13693.18098361756799542976@ietfa.amsl.com> In-Reply-To: <154002385712.13693.18098361756799542976@ietfa.amsl.com> From: Richard Barnes Date: Wed, 19 Dec 2018 11:46:12 -0500 Message-ID: To: Russ Housley Cc: gen-art@ietf.org, perc@ietf.org, IETF discussion list , draft-ietf-perc-double.all@ietf.org Content-Type: multipart/alternative; boundary="000000000000565040057d62c18b" Archived-At: Subject: Re: [Perc] Genart last call review of draft-ietf-perc-double-10 X-BeenThere: perc@ietf.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Privacy Enhanced RTP Conferencing List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 19 Dec 2018 16:46:33 -0000 --000000000000565040057d62c18b Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Thanks for the review, Russ. Comments below (nothing major); pull request here for your review: https://github.com/ietf/perc-wg/pull/163 On Sat, Oct 20, 2018 at 4:24 AM Russ Housley wrote: > Reviewer: Russ Housley > Review result: Almost Ready > > I am the assigned Gen-ART reviewer for this draft. The General Area > Review Team (Gen-ART) reviews all IETF documents being processed > by the IESG for the IETF Chair. Please treat these comments just > like any other last call comments. > > For more information, please see the FAQ at > . > > Document: draft-ietf-perc-double-10 > Reviewer: Russ Housley > Review Date: 2018-10-20 > IETF LC End Date: 2018-11-01 > IESG Telechat date: unknown > > Summary: Almost Ready > > > Major Concerns: > > Section 10: Doesn't the IANA registry needs to specify the PRF to be > used with the ciphersuite as well? > I don't think so. I don't see a slot in the relevant registry for that, and the tabular summary in the IANA considerations section is really just a courtesy. https://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml#srtp= -protection-1 > > Minor Concerns: > > Section 3: It would be useful to explain the Master Key before the > reader gets to Section 3.1. > Note that the "master key" concept comes from SRTP. I've added a bit of text to clarify. > Section 3.1: It is unclear what assistance is provided by the > additional level of indirection: > > PRF_double_n(k_master,x) =3D PRF_inner_(n/2)(k_master,x) || > PRF_outer_(n/2)(k_master,x) > > PRF_inner_n(k_master,x) =3D PRF_n(inner(k_master),x) > PRF_outer_n(k_master,x) =3D PRF_n(outer(k_master),x) > > It could just say: > > PRF_double_n(k_master,x) =3D PRF_(n/2)(inner(k_master),x) || > PRF_(n/2)(outer(k_master),x) > =F0=9F=91=8D Not sure what I was thinking. > Section 4: I suggest: > > If the marker bit is not present, then B MUST be set to zero. > =F0=9F=91=8D > Section 5, 1st paragraph: and endpoint cannot verify confidentiality. > Well, it can verify that the packet was encrypted with a key known only to the endpoints. But OK. > > Nits: > > The document uses "encryption" and "confidentiality" interchanagably. > Encryption is a mechanism or algorithm. Confidentiality is a security > service. While I do not think that the reader will be confused by the > current wording, it would be better to use the terms properly. In > addition, it is misleading to say: > > ... the receiving endpoint that can encrypt and authenticate ... > > because the sending endpoint encrypts, and the recieving endpoints > decrypts. Also, the receiving endpoints check the authentication tag. > That's actually just some bad grammar. Reworded. > Abstract: s/authenticated encryption with associated data/ > /authenticated encryption with associated data (AEAD)/ > > Abstract: s/scheme/algorithm/ > > Section 5.2: s/GCM/AES-GCM/ > > Section 7: s/HBH/hop-by-hop/ > > Section 7: s/E2E/end-to-end/ > > Section 7.1: s/HBH/hop-by-hop/ > > Section 7.2: The text is redundant. I suggest "etc" be dropped from > "such as SSRC, SEQ, CSRC, etc" > > Section 7.2: s/non primary/non-primary/ > > Section 7.3: s/HBH/hop-by-hop/ > Implemented all of the above... > Appendix A: s/HBH/hop-by-hop/ > > Appendix A: s/E2E/end-to-end/ > ... but I'm going to leave these last two as-is, for brevity. --000000000000565040057d62c18b Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Thanks for the revi= ew, Russ.=C2=A0 Comments below (nothing major); pull request here for your = review:


On Sat, Oct 20, 2018 at 4:24 AM Russ = Housley <housley@vigilsec.com> wrote:
Rev= iewer: Russ Housley
Review result: Almost Ready

I am the assigned Gen-ART reviewer for this draft. The General Area
Review Team (Gen-ART) reviews all IETF documents being processed
by the IESG for the IETF Chair.=C2=A0 Please treat these comments just
like any other last call comments.

For more information, please see the FAQ at
<http://wiki.tools.ietf.org/area/gen/trac/= wiki/GenArtfaq>.

Document: draft-ietf-perc-double-10
Reviewer: Russ Housley
Review Date: 2018-10-20
IETF LC End Date: 2018-11-01
IESG Telechat date: unknown

Summary: Almost Ready


Major Concerns:

Section 10: Doesn't the IANA registry needs to specify the PRF to be used with the ciphersuite as well?

I do= n't think so.=C2=A0 I don't see a slot in the relevant registry for= that, and the tabular summary in the IANA considerations section is really= just a courtesy.

=C2=A0

Minor Concerns:

Section 3: It would be useful to explain the Master Key before the
reader gets to Section 3.1.

Note that t= he "master key" concept comes from SRTP.=C2=A0 I've added a b= it of text to clarify.

=C2=A0
Section 3.1: It is unclear what assistance is provided by the
additional level of indirection:

=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0PRF_double_n(k_master,x) =3D PRF_inner_(n= /2)(k_master,x) ||
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2= =A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 PRF_outer_(n/2)(k_mast= er,x)

=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0PRF_inner_n(k_master,x)=C2=A0 =3D PRF_n(i= nner(k_master),x)
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0PRF_outer_n(k_master,x)=C2=A0 =3D PRF_n(o= uter(k_master),x)

It could just say:

=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0PRF_double_n(k_master,x) =3D PRF_(n/2)(in= ner(k_master),x) ||
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2= =A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 PRF_(n/2)(outer(k_mast= er),x)

=F0=9F=91=8D=C2=A0

Not sure what I was thinking.

=C2= =A0
Section 4: I suggest:

=C2=A0 =C2=A0 =C2=A0 =C2=A0 If the marker bit is not present, then B MUST b= e set to zero.

=F0=9F=91=8D
=C2=A0
Section 5, 1st paragraph: and endpoint cannot verify confidentiality.

Well, it can verify that the packet was encr= ypted with a key known only to the endpoints.=C2=A0 But OK.
= =C2=A0

Nits:

The document uses "encryption" and "confidentiality" in= terchanagably.
Encryption is a mechanism or algorithm.=C2=A0 Confidentiality is a security=
service.=C2=A0 While I do not think that the reader will be confused by the=
current wording, it would be better to use the terms properly.=C2=A0 In
addition, it is misleading to say:

=C2=A0 =C2=A0... the receiving endpoint that can encrypt and authenticate .= ..

because the sending endpoint encrypts, and the recieving endpoints
decrypts.=C2=A0 Also, the receiving endpoints check the authentication tag.=

That's actually just some bad gram= mar.=C2=A0 Reworded.

=C2=A0
Abstract: s/authenticated encryption with associated data/
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0/authenticated encryption with ass= ociated data (AEAD)/

Abstract: s/scheme/algorithm/

Section 5.2: s/GCM/AES-GCM/

Section 7: s/HBH/hop-by-hop/

Section 7: s/E2E/end-to-end/

Section 7.1: s/HBH/hop-by-hop/

Section 7.2: The text is redundant.=C2=A0 I suggest "etc" be drop= ped from
"such as SSRC, SEQ, CSRC, etc"

Section 7.2: s/non primary/non-primary/

Section 7.3: s/HBH/hop-by-hop/

Implemen= ted all of the above...
=C2=A0
Appendix A: s/HBH/hop-by-hop/

Appendix A: s/E2E/end-to-end/

... but I= 'm going to leave these last two as-is, for brevity.
--000000000000565040057d62c18b--