[pim] IGMP "General Query" "Group-Specific Query" src 0.0.0.0 and the Linux Kernel

<mal.hubert@bt.com> Thu, 14 March 2019 13:40 UTC

Return-Path: <mal.hubert@bt.com>
X-Original-To: pim@ietfa.amsl.com
Delivered-To: pim@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 78DC2130E5B for <pim@ietfa.amsl.com>; Thu, 14 Mar 2019 06:40:29 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.168
X-Spam-Level:
X-Spam-Status: No, score=-1.168 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HTML_MESSAGE=0.001, SPF_HELO_SOFTFAIL=0.732, SPF_PASS=-0.001] autolearn=no 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 J0zBECoXzf3n for <pim@ietfa.amsl.com>; Thu, 14 Mar 2019 06:40:27 -0700 (PDT)
Received: from smtpb1.bt.com (smtp-ec.bt.com [213.121.32.92]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id D052012F19D for <pim@ietf.org>; Thu, 14 Mar 2019 06:40:26 -0700 (PDT)
Received: from rew09926dag07d.domain1.systemhost.net (10.55.202.46) by bwp09926066.bt.com (10.50.151.89) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384_P256) id 15.1.1531.3; Thu, 14 Mar 2019 13:40:21 +0000
Received: from rew09926dag07b.domain1.systemhost.net (10.55.202.38) by rew09926dag07d.domain1.systemhost.net (10.55.202.46) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Thu, 14 Mar 2019 13:40:23 +0000
Received: from rew09926dag07b.domain1.systemhost.net ([fe80::3597:bc94:cdb8:9d49]) by rew09926dag07b.domain1.systemhost.net ([fe80::3597:bc94:cdb8:9d49%12]) with mapi id 15.00.1395.000; Thu, 14 Mar 2019 13:40:23 +0000
From: <mal.hubert@bt.com>
To: <pim@ietf.org>
Thread-Topic: IGMP "General Query" "Group-Specific Query" src 0.0.0.0 and the Linux Kernel
Thread-Index: AdTaa3iYORVxJFnQTaafayn3vG7+0w==
Date: Thu, 14 Mar 2019 13:40:22 +0000
Message-ID: <c4af343ecd81487199af28bfa1446bb9@rew09926dag07b.domain1.systemhost.net>
Accept-Language: en-GB, en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
x-ms-exchange-transport-fromentityheader: Hosted
x-originating-ip: [10.55.202.233]
Content-Type: multipart/alternative; boundary="_000_c4af343ecd81487199af28bfa1446bb9rew09926dag07bdomain1sy_"
MIME-Version: 1.0
Archived-At: <https://mailarchive.ietf.org/arch/msg/pim/y6zepMBXD6Rmb454LUeqOnbywrQ>
Subject: [pim] IGMP "General Query" "Group-Specific Query" src 0.0.0.0 and the Linux Kernel
X-BeenThere: pim@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Protocol Independent Multicast <pim.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/pim>, <mailto:pim-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/pim/>
List-Post: <mailto:pim@ietf.org>
List-Help: <mailto:pim-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/pim>, <mailto:pim-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 14 Mar 2019 13:40:30 -0000

Hey

Hopefully someone on here can answer this basic query for me. It would appear that the Linux kernel by default will allow IGMPv3 "General Query" if it has a source IP of 0.0.0.0 but will drop any "Group-Specific Queries" if the source IP is 0.0.0.0. This doesn't appear to be specific to my implementation and seems to be the implementation in the Linux Kernel.

Some questions about this, if someone would be so kind as to help.


1)    Is this by design in the rfc3367 standard and would someone point out to me where it is and enlighten me as to why this is the case.

2)    Is this by design in the Kernel and would enlighten me as to why this is the case.

3)    Is this a bug in the Kernel and would it be worth raising on Kernel Bugzilla.

Many Thanks

Mal Hubert