Re: [dmarc-ietf] Errors in RFC 8601, was Question about changes introduced by erratum

John R Levine <johnl@taugh.com> Sun, 22 March 2020 19:41 UTC

Return-Path: <johnl@taugh.com>
X-Original-To: dmarc@ietfa.amsl.com
Delivered-To: dmarc@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id C535E3A0870 for <dmarc@ietfa.amsl.com>; Sun, 22 Mar 2020 12:41:35 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.1
X-Spam-Level:
X-Spam-Status: No, score=-2.1 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1536-bit key) header.d=iecc.com header.b=mAW6kM/W; dkim=pass (1536-bit key) header.d=taugh.com header.b=Oca0qNie
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 4UngiIK7-oxs for <dmarc@ietfa.amsl.com>; Sun, 22 Mar 2020 12:41:34 -0700 (PDT)
Received: from gal.iecc.com (gal.iecc.com [IPv6:2001:470:1f07:1126:0:43:6f73:7461]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 1835C3A086F for <dmarc@ietf.org>; Sun, 22 Mar 2020 12:41:33 -0700 (PDT)
Received: (qmail 9519 invoked from network); 22 Mar 2020 19:41:31 -0000
DKIM-Signature: v=1; a=rsa-sha256; c=simple; d=iecc.com; =?utf-8?q?h=3Ddate?= =?utf-8?q?=3Amessage-id=3Afrom=3Ato=3Asubject=3Ain-reply-to=3Areferences=3A?= =?utf-8?q?mime-version=3Acontent-type=3Auser-agent=3B?= s=252b.5e77bf6b.k2003; i=johnl-iecc.com@submit.iecc.com; =?utf-8?q?bh=3DCLDaIP4IadsIuouJLD0o+uD7RunX6YBoUgA+IqdgdIg=3D=3B_b=3DmAW6kM?= =?utf-8?q?/WtVOb+y3bHpkROEmz0yup15297rr9l+Ggk1lYtcZ7B5kdNI0DRjBVHJKz3HbEStc?= =?utf-8?q?J60uGskKk+uJ27Zr4AaVAPGzXS6vXp+NqmIG8oKir6VDQdU8RkIhsqDnE/rDgKU3D?= =?utf-8?q?xbT91GGJzy3tBv6GixfzZmx1RSlx8Ft3hOU3laBWstey3lFroc7wkGqnooijMQUxo?= =?utf-8?q?0nnT7F7Gk4my+ijd0OVYiQgvudg9M9plRKDpzdYOqvA8FQL8y0A4ZTF?=
DKIM-Signature: v=1; a=rsa-sha256; c=simple; d=taugh.com; =?utf-8?q?h=3Ddate?= =?utf-8?q?=3Amessage-id=3Afrom=3Ato=3Asubject=3Ain-reply-to=3Areferences=3A?= =?utf-8?q?mime-version=3Acontent-type=3Auser-agent=3B?= s=252b.5e77bf6b.k2003; olt=johnl-iecc.com@submit.iecc.com; =?utf-8?q?bh=3DCLDaIP4IadsIuouJLD0o+uD7RunX6YBoUgA+IqdgdIg=3D=3B_b=3DOca0qN?= =?utf-8?q?ieZnCmc29lYUQ0kVSe49Y8fhl8PHFv4tFbVXWd86qCh/ObGiyB8EY4T1OaQgbF3ky?= =?utf-8?q?Kr3uMIFji7TLrylVUUjLK0cXwsOF8iWujiJVSKpPlp1AcTkII38XsUFTzbnVDUtqg?= =?utf-8?q?XfFC2fNOd4pLTCP4f2D9xlgdhDkHKw1CgVW5lG/Io//8mH5JscKHeJpsKn7bmpsLc?= =?utf-8?q?06oYPSkNalYF5DVhUA2ezyJ9igSXsWz7kRXiwQbeEVTuxo56LYvCzHP?=
Received: from localhost ([IPv6:2001:470:1f07:1126::78:696d:6170]) by imap.iecc.com ([IPv6:2001:470:1f07:1126::78:696d:6170]) with ESMTPSA (TLS1.3 ECDHE-RSA AES-256-GCM AEAD, johnl@iecc.com) via TCP6; 22 Mar 2020 19:41:30 -0000
Date: 22 Mar 2020 15:41:30 -0400
Message-ID: <alpine.OSX.2.22.407.2003221534100.16773@ary.qy>
From: "John R Levine" <johnl@taugh.com>
To: "Damian Lukowski" <rfc@arcsin.de>, dmarc@ietf.org
In-Reply-To: <09ec8dda-7165-fae8-f8e1-f88561085e47@arcsin.de>
References: <20200322154438.14E02166129A@ary.qy> <09ec8dda-7165-fae8-f8e1-f88561085e47@arcsin.de>
User-Agent: Alpine 2.22 (OSX 407 2020-02-09)
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII; format=flowed
Archived-At: <https://mailarchive.ietf.org/arch/msg/dmarc/GSc0Xnu7l4fnoqJU4zZD3M6Q1j8>
Subject: Re: [dmarc-ietf] Errors in RFC 8601, was Question about changes introduced by erratum
X-BeenThere: dmarc@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: "Domain-based Message Authentication, Reporting, and Compliance \(DMARC\)" <dmarc.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/dmarc>, <mailto:dmarc-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/dmarc/>
List-Post: <mailto:dmarc@ietf.org>
List-Help: <mailto:dmarc-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/dmarc>, <mailto:dmarc-request@ietf.org?subject=subscribe>
X-List-Received-Date: Sun, 22 Mar 2020 19:41:36 -0000

>> RFC5321.MailFrom is the address in the SMTP "Mail From" command
>
> So is RFC5321.MailFrom the Reverse-Path from RFC5321, or only the
> Mailbox part of a Reverse-Path? I would expect it to be the full
> Reverse-path, because

RFCs 2821 and 5321 say:

    Historically, the <reverse-path> was permitted to contain more than
    just a mailbox; however, contemporary systems SHOULD NOT use source
    routing (see Appendix C).

Source routes have been deprecated for 20 years.  We can forget about 
them.

> and a Return-Path field usually contains "<" ... ">", so it cannot be a
> plain Mailbox.

No, see RFC 2821 or 5321 sec 3.3.  The reverse-path is what's between the 
brackets, which means it's a mailbox or it's empty.

> By the way, an RFC5321 mailbox allows address-literals which are not
> covered by the right hand side of RFC8601's pvalue, and one cannot use
> the left hand side because of

I haven't seen an address literal in non-spam mail for over a decade 
either.  I'm pretty sure we can forget about them in A-R headers, too.

R's,
John