On Sun, 29 May 2005, william(at)elan.net wrote:
You probably all know that I have a problem with how SID drafts say
Resent header fields are to be used...
Well, just out of curiosity I wanted to know how they are they really
used in the real world and lucky me I use one of those mail clients
that actually supports it (though I've never tried this feature before
and kind of came upon it by accident).
Anyway, I'm going to demonstrate (and also test it with mail list) in
a moment as I forward copy of this post back here with resent headers.
Ok, the demonstration with mail lists did not worked quite as I would have
liked - mxcomp list-processor stripped off the Resent- header fields and
spf-discuss did not let the mail through at all (probably is doing
checking on return-path and saw it was not the one I signed up with,
even though From and everything else is correct). Anyway, here is what
mail header looks like when I resent the message:
-------------------------------------------------------------------------
Return-Path: <william(_at_)elan(_dot_)net>
Delivered-To: william(_at_)completewhois(_dot_)com
Received: from sokol.elan.net (sokol.elan.net [216.151.192.200])
by mail.completewhois.com (Postfix) with ESMTP id AAAE918B13
for <william(_at_)completewhois(_dot_)com>; Sun, 29 May 2005 08:07:22 -0700
(PDT)
Received: from sokol.elan.net (sokol [127.0.0.1])
by sokol.elan.net (8.13.1/8.13.1) with ESMTP id j4TEdcI6028819
for <william(_at_)completewhois(_dot_)com>; Sun, 29 May 2005 07:39:38 -0700
Received: from localhost (william(_at_)localhost)
by sokol.elan.net (8.13.1/8.13.1/Submit) with ESMTP id j4TEdcuj028816
for <william(_at_)completewhois(_dot_)com>; Sun, 29 May 2005 07:39:38 -0700
X-Authentication-Warning: sokol.elan.net: william owned process doing -bs
X-Return-Path:
<listbox+trampoline+735+986489+f3b742cf(_at_)v2(_dot_)listbox(_dot_)com>
X-Received: from rune.listbox.com (rune.listbox.com [208.210.124.79])
by sokol.elan.net (8.13.1/8.13.1) with ESMTP id j4TEVVvB028770
for <william(_at_)elan(_dot_)net>; Sun, 29 May 2005 07:31:31 -0700
X-Received: from localhost.localdomain (localhost [127.0.0.1])
by rune.listbox.com (Postfix) with ESMTP id 3C3AB18ACF
for <william(_at_)elan(_dot_)net>; Sun, 29 May 2005 10:31:30 -0400 (EDT)
X-Received: from localhost.localdomain (localhost [127.0.0.1])
by rune.listbox.com (Postfix) with ESMTP id 3C3AB18ACF
for <william(_at_)elan(_dot_)net>; Sun, 29 May 2005 10:31:30 -0400 (EDT)
X-Received: from sokol.elan.net (sokol.elan.net [216.151.192.200])
by rune.listbox.com (Postfix) with ESMTP id 94AC6189D6
for <spf-discuss(_at_)v2(_dot_)listbox(_dot_)com>; Sun, 29 May 2005
10:31:11 -0400 (EDT)
X-Received: from sokol.elan.net (sokol [127.0.0.1])
by sokol.elan.net (8.13.1/8.13.1) with ESMTP id j4TEV6SP028764;
Sun, 29 May 2005 07:31:07 -0700
X-Received: from localhost (william(_at_)localhost)
by sokol.elan.net (8.13.1/8.13.1/Submit) with ESMTP id j4TEV6wZ028761;
Sun, 29 May 2005 07:31:06 -0700
X-Authentication-Warning: sokol.elan.net: william owned process doing -bs
Date: Sun, 29 May 2005 07:31:06 -0700 (PDT)
From: "william(at)elan.net" <william(_at_)elan(_dot_)net>
To: spf-discuss(_at_)v2(_dot_)listbox(_dot_)com
Cc: spf-discuss(_at_)v2(_dot_)listbox(_dot_)com
Subject: [spf-discuss] Resent- header fields
Message-ID:
<Pine(_dot_)LNX(_dot_)4(_dot_)62(_dot_)0505290715250(_dot_)15027(_at_)sokol(_dot_)elan(_dot_)net>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed
Sender: owner-spf-discuss(_at_)v2(_dot_)listbox(_dot_)com
Precedence: list
Reply-To: spf-discuss(_at_)v2(_dot_)listbox(_dot_)com
List-ID: <spf-discuss(_at_)v2(_dot_)listbox(_dot_)com>
List-Software: listbox.com v2.0
List-Help:
<http://v2.listbox.com/doc/help_sub?list_name=spf-discuss(_at_)v2(_dot_)listbox(_dot_)com
>
List-Subscribe: <mailto:subscribe-spf-discuss(_at_)v2(_dot_)listbox(_dot_)com>,
<http://v2.listbox.com/subscribe/?listname=spf-discuss(_at_)v2(_dot_)listbox(_dot_)com>
List-Unsubscribe:
<mailto:unsubscribe-spf-discuss(_at_)v2(_dot_)listbox(_dot_)com>,
<http://v2.listbox.com/member/unsubscribe/?listname=spf-discuss(_at_)v2(_dot_)listb
ox.com>
Errors-To:
listbox+trampoline+735+986489+f3b742cf(_at_)v2(_dot_)listbox(_dot_)com
ReSent-Date: Sun, 29 May 2005 07:39:31 -0700 (PDT)
Resent-From: "william(at)elan.net" <william(_at_)elan(_dot_)net>
Resent-To: william(_at_)completewhois(_dot_)com
ReSent-Subject: [spf-discuss] Resent- header fields
ReSent-Message-ID:
<Pine(_dot_)LNX(_dot_)4(_dot_)62(_dot_)0505290739310(_dot_)15027(_at_)sokol(_dot_)elan(_dot_)net>
--------------------------------------------------------------------------
To be fair, I don't quite agree with how Pine did it as it put Resent-
below the reset of the message header and not above it. I looked at
RFC2822 and it says there:
"All of the resent fields corresponding to a particular resending of the
message SHOULD be together. Each new set of resent fields is prepended
to the message; that is, the most recent set of resent fields appear
earlier in the message."
I have a feeling its the word "prepended" that caused problem as some
may understand as something being added before (below) the rest of the
header data, but its use in RFC2822 seems consistent with how Received
fields are added on top of the rest of the header data and example with
Resent- is also such that they are added on top.
Besides that Pine also quite interestingly changed the data and replaced
all trace fields with "X-" (but did not touch any other fields then
Received or Return-Path). In any case this all very clearly demonstrates
that its new message and not the original when the message is resent.
So the use of this for standard non-MUA forwarding is not correct at
all and would be in conflict with current systems that currently do
use the fields (even if not quite right according to RFC2822, which BTW
I intend to report as bug to Pine developers). Yes I know this all does
not matter to Microsoft - none of their MUAs like outlook support Resent -
but it does not mean others dont and protecting those other systems that
follow standards should be more important.
---
William Leibzon, Elan Networks:
mailto: william(_at_)elan(_dot_)net
Anti-Spam and Email Security Research Worksite:
http://www.elan.net/~william/emailsecurity/