IETF Logo Mail Archive

Re: [dmarc-ietf] Proposing an extension to DMARC to optionally require SPF and DKIM

"John Levine" <johnl@taugh.com> Tue, 02 April 2013 00:46 UTC

Return-Path: <johnl@iecc.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 83DA911E80E2 for <dmarc@ietfa.amsl.com>; Mon, 1 Apr 2013 17:46:07 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -110.642
X-Spam-Level:
X-Spam-Status: No, score=-110.642 tagged_above=-999 required=5 tests=[AWL=0.557, BAYES_00=-2.599, HABEAS_ACCREDITED_SOI=-4.3, RCVD_IN_BSP_TRUSTED=-4.3, USER_IN_WHITELIST=-100]
Received: from mail.ietf.org ([12.22.58.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Lwpj5bvjjBMf for <dmarc@ietfa.amsl.com>; Mon, 1 Apr 2013 17:46:07 -0700 (PDT)
Received: from leila.iecc.com (leila6.iecc.com [IPv6:2001:470:1f07:1126:0:4c:6569:6c61]) by ietfa.amsl.com (Postfix) with ESMTP id C675421F8CEE for <dmarc@ietf.org>; Mon, 1 Apr 2013 17:45:51 -0700 (PDT)
Received: (qmail 15061 invoked from network); 2 Apr 2013 00:45:51 -0000
Received: from leila.iecc.com (64.57.183.34) by mail1.iecc.com with QMQP; 2 Apr 2013 00:45:51 -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:vbr-info; s=515a2a3e.xn--9vv.k1304; i=johnl@user.iecc.com; bh=cHt3J2/Jj8NB5JVIFz059XztI8IMiLUlS7sl5jKv7Jk=; b=TR8nDYMhPwLL6VVtnHWXykUA7H+JM5GL1JA3+ytn5a9bNdQRworlOpgK5owLJ1W2+lJCvwj467x0XptySXxoozOueTrw6MTxzPIsBxGPFYoOmsBBTDicOrOqyaUM3e2F5tfwtcpqZj9PyGyOMyZ5+d3NnVY+Jev3k3+MFTDjgYg=
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:vbr-info; s=515a2a3e.xn--9vv.k1304; olt=johnl@user.iecc.com; bh=cHt3J2/Jj8NB5JVIFz059XztI8IMiLUlS7sl5jKv7Jk=; b=dvcN/e14KDRzM+WU53gSGsi6X/hEJ094ItgCHPhEDDKCHxzcRfJ7iSH2io9lIA9avpcisiR5hrxwW1Ys2cqJEMFWKMiMrrQ1IpibT+qZUlNCtBkysYeowzkvwuodjQigJ0GiOPGuw9V1Wz71dXM9epzWdgtZ+Lhk+eG+qYwUmgs=
VBR-Info: md=iecc.com; mc=all; mv=dwl.spamhaus.org
Date: Tue, 02 Apr 2013 00:45:28 -0000
Message-ID: <20130402004528.6146.qmail@joyce.lan>
From: John Levine <johnl@taugh.com>
To: dmarc@ietf.org
In-Reply-To: <3ba7c7a04f5f45cb95930ec99926ccc9@BL2SR01MB605.namsdf01.sdf.exchangelabs.com>
Organization:
X-Headerized: yes
Mime-Version: 1.0
Content-type: text/plain; charset="utf-8"
Content-transfer-encoding: 7bit
Cc: tzink@exchange.microsoft.com
Subject: Re: [dmarc-ietf] Proposing an extension to DMARC to optionally require SPF and DKIM
X-BeenThere: dmarc@ietf.org
X-Mailman-Version: 2.1.12
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: <http://www.ietf.org/mail-archive/web/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: Tue, 02 Apr 2013 00:46:07 -0000

> You are correct that you lose the path independence. But it is
> incorrect to say you gain nothing - you gain the ability to say
> "Nobody else can spoof me." 

Nope.  As I said, Terry's proposal adds nothing beyond the
configuration I described.  Please reread the message to which you
were responding more carefully, paying particular attention to the
difference between SPF pass and neutral.  Really, you gain nothing.

>Shouldn't it be the choice of the sender whether or not they want to make this assertion and subsequent
>trade-off?

The sender can make any assertion it wants, but it better not assume
that anyone is paying attention.  The more complicated the assertions,
the less likely that receivers will think it's worth the effort to
interpret them.

R's,
John

v2.23.0 | Report a Bug | By Email