Re: [ietf-smtp] Possible cont4ibution to moving forward with RFC5321bis SMTP

"John Levine" <johnl@taugh.com> Thu, 02 January 2020 22:33 UTC

Return-Path: <johnl@iecc.com>
X-Original-To: ietf-smtp@ietfa.amsl.com
Delivered-To: ietf-smtp@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 99665120110 for <ietf-smtp@ietfa.amsl.com>; Thu, 2 Jan 2020 14:33:40 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.749
X-Spam-Level:
X-Spam-Status: No, score=-1.749 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, HEADER_FROM_DIFFERENT_DOMAINS=0.25, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=no autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1536-bit key) header.d=iecc.com header.b=bIIIidoc; dkim=pass (1536-bit key) header.d=taugh.com header.b=Qpoi1Iuu
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 TVdH104ixqUq for <ietf-smtp@ietfa.amsl.com>; Thu, 2 Jan 2020 14:33:39 -0800 (PST)
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 AA2811200E6 for <ietf-smtp@ietf.org>; Thu, 2 Jan 2020 14:33:39 -0800 (PST)
Received: (qmail 86550 invoked from network); 2 Jan 2020 22:33:38 -0000
DKIM-Signature: v=1; a=rsa-sha256; c=simple; d=iecc.com; h=date:message-id:from:to:cc:subject:in-reply-to:mime-version:content-type:content-transfer-encoding; s=15214.5e0e6fc2.k2001; i=printer-iecc.com@submit.iecc.com; bh=++6lUo1KUzdQIdua8PP+cg2KlBZUm0wpep3MbYhu9LA=; b=bIIIidocHF03H6G0mYRX8zNdCJxqirO6vbm0h0ImteAPy8OMQnGczSlSyCOgbDVFDWQ0cp9+wgBA37rkwPnnmNz0biq06pQGVdRBGLJIPkVeFcof0JPy50zN9Z8t6htKq10qp2X9AfmwIJMOqilt8WgJUZhIBp3LOYADVRDctJaTtXxKg4WcOlIFq1O9GtqJMosAXS4zI9sqIo2LGBkJYHS2oAl7XzaI4KA3ueYYjbu5Nm55kLWX6Gj1JZ3Brh3v
DKIM-Signature: v=1; a=rsa-sha256; c=simple; d=taugh.com; h=date:message-id:from:to:cc:subject:in-reply-to:mime-version:content-type:content-transfer-encoding; s=15214.5e0e6fc2.k2001; olt=printer-iecc.com@submit.iecc.com; bh=++6lUo1KUzdQIdua8PP+cg2KlBZUm0wpep3MbYhu9LA=; b=Qpoi1IuuBbEY89uaSZn3TUxmZU6oetzcqE3pvaqmeFFMX+IX9TWGC0Vl82OATQLvFJuhYDnaiLBSN4oB5j1UzfkVvhAL1Gdu4fChgFdipthMoCkv5tNDvueP2BZf5mnkuBUhv+PEI4MpPjAYdPBUdTejfrj9pZ0+fHHaPYDrKxotO/+mleANMFuryWKIyihm9yQZg/aXIzy/7gjxCOc96ETVIiT4b9afr4+EdOupzA2Ikd6wgtOIB8z3gaFJ4+1D
Received: from ary.qy ([IPv6:2001:470:1f07:1126::78:696d:6170]) by imap.iecc.com ([IPv6:2001:470:1f07:1126::78:696d:6170]) with ESMTPSA (TLS1.2 ECDHE-RSA AES-256-GCM AEAD, printer@iecc.com) via TCP6; 02 Jan 2020 22:33:38 -0000
Received: by ary.qy (Postfix, from userid 501) id 18A2211EB91B; Thu, 2 Jan 2020 17:33:37 -0500 (EST)
Date: Thu, 02 Jan 2020 17:33:37 -0500
Message-Id: <20200102223338.18A2211EB91B@ary.qy>
From: John Levine <johnl@taugh.com>
To: ietf-smtp@ietf.org
Cc: arnt@gulbrandsen.priv.no
In-Reply-To: <501e94b2-1f76-442a-8c3e-a3bc46c51aca@gulbrandsen.priv.no>
Organization: Taughannock Networks
X-Headerized: yes
Mime-Version: 1.0
Content-type: text/plain; charset="utf-8"
Content-transfer-encoding: 8bit
Archived-At: <https://mailarchive.ietf.org/arch/msg/ietf-smtp/-DAezuwkp5nbr-a648CKFotqP5E>
Subject: Re: [ietf-smtp] Possible cont4ibution to moving forward with RFC5321bis SMTP
X-BeenThere: ietf-smtp@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: "Discussion of issues related to Simple Mail Transfer Protocol \(SMTP\) \[RFC 821, RFC 2821, RFC 5321\]" <ietf-smtp.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ietf-smtp>, <mailto:ietf-smtp-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ietf-smtp/>
List-Post: <mailto:ietf-smtp@ietf.org>
List-Help: <mailto:ietf-smtp-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ietf-smtp>, <mailto:ietf-smtp-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 02 Jan 2020 22:33:40 -0000

In article <501e94b2-1f76-442a-8c3e-a3bc46c51aca@gulbrandsen.priv.no> you write:
>One way to disagree is about IP address family.
>
>If I remember correctly, nothing (else) in 5321/2 requires a v6-only host 
>to understand anything about v4. Running a v6-only host is stupid at this 
>point, perhaps slightly less stupid in five years, but even so I don't 
>think the next RFCs should feature an IPv4 requirement for address 
>literals, and nothing for the main parts of the protocols.

Assuming we keep address literals as part of SMTP (which I think would
be a mistake) rather than submission (where I don't care), I think the
as-if rule applies.

If a host doesn't get v4 connections, it doesn't need to recognize v4
address literals.  Similarly, if it doesn't get v6 connections it
doesn't need to recognize v6 literals.  Standards are about
interoperation, and cases that never happen don't matter for interop.

R's,
John