Re: [dmarc-ietf] Ticket #42 - Expand DMARC reporting URI functionality

Alessandro Vesely <vesely@tana.it> Thu, 31 December 2020 16:35 UTC

Return-Path: <vesely@tana.it>
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 8A1063A0D9B for <dmarc@ietfa.amsl.com>; Thu, 31 Dec 2020 08:35:09 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.099
X-Spam-Level:
X-Spam-Status: No, score=-2.099 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, NICE_REPLY_A=-0.001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1152-bit key) header.d=tana.it
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 WQ3BsKvEwdYc for <dmarc@ietfa.amsl.com>; Thu, 31 Dec 2020 08:35:08 -0800 (PST)
Received: from wmail.tana.it (wmail.tana.it [62.94.243.226]) (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 29FA13A0D9A for <dmarc@ietf.org>; Thu, 31 Dec 2020 08:35:07 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tana.it; s=delta; t=1609432506; bh=wkRsdM4enaSZgWsM6OTYXYFBq3AFaMOjjhhVAGrkons=; l=1210; h=To:References:From:Date:In-Reply-To; b=Cro2qiPdIQc+dhTI/BjjIcpDUU0BNsujscTJzM9DnrD9HQdE15sV76fWWX/DQRtHa 0GJdjtrOZZD/rdt9hPK5MGGsAzjjjP10uuazF1hv/pTLw+0ae0/qWTCBABsTrlyof/ vqdEAt/utyJb0asJZWtU9s/ph0SQO0xk7RiQ3FeTPujVONapeaduKPzy/CF3j
Authentication-Results: tana.it; auth=pass (details omitted)
Original-From: Alessandro Vesely <vesely@tana.it>
Received: from [172.25.197.111] (pcale.tana [172.25.197.111]) (AUTH: CRAM-MD5 uXDGrn@SYT0/k, TLS: TLS1.3, 128bits, ECDHE_RSA_AES_128_GCM_SHA256) by wmail.tana.it with ESMTPSA id 00000000005DC053.000000005FEDFDBA.00001F82; Thu, 31 Dec 2020 17:35:06 +0100
To: John R Levine <johnl@taugh.com>, dmarc@ietf.org
References: <eb3d06f-c89f-2511-3528-d421473e4d42@taugh.com> <a67a4e98-2be0-e2e2-2595-c12d9b87c4df@taugh.com> <7d3be6c4-aa17-3c34-d8f0-4df51e46ccc1@tana.it> <f12991fe-fded-6c0-528c-3b879b4a670@taugh.com>
From: Alessandro Vesely <vesely@tana.it>
Message-ID: <8b6605de-ca01-904c-de78-deae254e0891@tana.it>
Date: Thu, 31 Dec 2020 17:35:05 +0100
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0
MIME-Version: 1.0
In-Reply-To: <f12991fe-fded-6c0-528c-3b879b4a670@taugh.com>
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Archived-At: <https://mailarchive.ietf.org/arch/msg/dmarc/tvHEglw-wYJqA7GD6qMp43HKaos>
Subject: Re: [dmarc-ietf] Ticket #42 - Expand DMARC reporting URI functionality
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: Thu, 31 Dec 2020 16:35:10 -0000

On Thu 31/Dec/2020 16:37:38 +0100 John R Levine wrote:
> On Thu, 31 Dec 2020, Alessandro Vesely wrote:
> 
>> On Wed 30/Dec/2020 22:23:20 +0100 John R Levine wrote:
>>> [ add ruap= to allow https in preference to mailto ]
>>
>> I still like better sticking to a unique tag (rua=) and applying OR-slashes. 
>> With a comma, it is backward compatible:
>>
>> v=DMARC1; p=none; rua=mailto:local@example.com, mailto:report@service.example, /https://service.example/report/;
> 
> No, it's invalid according to the syntax in RFC 7489.


I see.  We have:

     dmarc-auri      = "rua" *WSP "=" *WSP
                        dmarc-uri *(*WSP "," *WSP dmarc-uri)

     URI             = scheme ":" hier-part [ "?" query ] [ "#" fragment ]

     scheme      = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )

So /https cannot be a scheme.  How about:

     v=DMARC1; p=none; rua=mailto:local@example.com, mailto:report@service.example, OR-https://service.example/report/;


> We have no idea what existing implementations do with DMARC records with syntax errors.
> 
> Here's an experiment -- put that slash syntax in the rua= in your DMARC record 
> and see who does or doesn't continue sending reports.


Done, with the second alternative.


Best
Ale
--