Re: [ietf-smtp] broken signatures, was Curious

John C Klensin <john-ietf@jck.com> Tue, 21 July 2020 22:12 UTC

Return-Path: <john-ietf@jck.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 D28663A0B18 for <ietf-smtp@ietfa.amsl.com>; Tue, 21 Jul 2020 15:12:37 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.897
X-Spam-Level:
X-Spam-Status: No, score=-1.897 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_NONE=0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
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 Utz_qSQYba9x for <ietf-smtp@ietfa.amsl.com>; Tue, 21 Jul 2020 15:12:36 -0700 (PDT)
Received: from bsa3.jck.com (bsa3.jck.com [65.175.133.137]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id A49D13A0B15 for <ietf-smtp@ietf.org>; Tue, 21 Jul 2020 15:12:36 -0700 (PDT)
Received: from hp5.int.jck.com ([198.252.137.153] helo=JcK-HP5.jck.com) by bsa3.jck.com with esmtp (Exim 4.82 (FreeBSD)) (envelope-from <john-ietf@jck.com>) id 1jy0V1-0000Hw-0i; Tue, 21 Jul 2020 18:12:35 -0400
Date: Tue, 21 Jul 2020 18:12:30 -0400
From: John C Klensin <john-ietf@jck.com>
To: Paul Smith <paul@pscs.co.uk>, ietf-smtp@ietf.org
Message-ID: <EBF1D7AD5471D2B435BEDD78@JcK-HP5.jck.com>
In-Reply-To: <511f7536-cdc0-0bd3-e0bc-f5caa25fbd90@pscs.co.uk>
References: <20200721201938.D4F7D1D5CAD3@ary.qy> <5F1753DF.5000106@isdg.net> <511f7536-cdc0-0bd3-e0bc-f5caa25fbd90@pscs.co.uk>
X-Mailer: Mulberry/4.0.8 (Win32)
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
Archived-At: <https://mailarchive.ietf.org/arch/msg/ietf-smtp/tt_yyGrrGRB1MP52KTkA_cuSqdA>
Subject: Re: [ietf-smtp] broken signatures, was Curious
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: Tue, 21 Jul 2020 22:12:38 -0000


--On Tuesday, 21 July, 2020 22:41 +0100 Paul Smith
<paul@pscs.co.uk> wrote:

>...
> The former ones tell me something. It may or may not be that
> useful. It may nor may not be true, but it tells me something.
> The latter ones tell me (the recipient) nothing at all. I'm
> honestly not sure why the latter data is in the headers at all.
> 
> It *may* be that if I ask for support from Paypal about an
> email, they'll ask me 'What was the
> "X-PP-Email-Transmission-Id'' header in that message? But I
> seriously doubt that would happen. If it did, then adding that
> header is OK, otherwise, no. In any case, the Message-ID
> should be sufficient for them to trace it if that's what they
> need to do.
> 
> The former set may be more useful if it was tagged with WHICH
> server added those headers, but that's it.

Is it the case that, if we wanted to make these useful, we'd be
considering a way to make those fields into trace fields, with
all of the time-stamping and server (or other supplying entity)
information that implies?    Non-trivial work and something that
would certainly have to be done as a new Proposed Standard or
Experimental spec, not in 5321bis, but maybe an interesting
question.

FWIW, it is a question: I have no idea whether it would be a
good idea.

    john