From patchwork Wed Sep 2 03:22:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Davey X-Patchwork-Id: 1355503 Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=alliedtelesis.co.nz Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=alliedtelesis.co.nz header.i=@alliedtelesis.co.nz header.a=rsa-sha256 header.s=mail181024 header.b=qrzK4Iy5; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4Bh8QN0nTyz9sSJ for ; Wed, 2 Sep 2020 13:22:51 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726426AbgIBDWj (ORCPT ); Tue, 1 Sep 2020 23:22:39 -0400 Received: from gate2.alliedtelesis.co.nz ([202.36.163.20]:39637 "EHLO gate2.alliedtelesis.co.nz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726269AbgIBDWi (ORCPT ); Tue, 1 Sep 2020 23:22:38 -0400 Received: from mmarshal3.atlnz.lc (mmarshal3.atlnz.lc [10.32.18.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by gate2.alliedtelesis.co.nz (Postfix) with ESMTPS id 46988806B5; Wed, 2 Sep 2020 15:22:35 +1200 (NZST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alliedtelesis.co.nz; s=mail181024; t=1599016955; bh=pA5jZtYGbadRL6MpsDi7RfTcACMi8fe+m3GaZOwbkX0=; h=From:To:Cc:Subject:Date; b=qrzK4Iy5fijirooHGX6wQqbMYHJO6KCGCNbWqPU28KOlSHlSjn07DQIHz0ooIfIge SSM7i7gyOmlEXUORuavt7AIx2CLIunu029fhJJs6l0MGg9JpO9DuMFzxv5IM4wzr9q 70XnRE3c9sYK1EDVGpkEb6r9Vvnt8fA9xeEDTnlEAaDjs4KGsVbT0hCdwxLSYXUkrD /M4EHWCqpugnffM09s/yusc9WfaKhCAjM5raHLU0UFnC9AJe1PMw/ZDUx2oZjmnr+R S/7K9lQNK9R4ySd6wyBo1R8m3N2UP1ayW4ZQBxNIkxGYnhpQJ/YeQj2tRUoWFN87nd WBv6E23XJYFpw== Received: from smtp (Not Verified[10.32.16.33]) by mmarshal3.atlnz.lc with Trustwave SEG (v7,5,8,10121) id ; Wed, 02 Sep 2020 15:22:35 +1200 Received: from pauld-dl.ws.atlnz.lc (pauld-dl.ws.atlnz.lc [10.33.23.16]) by smtp (Postfix) with ESMTP id C161413EEBA; Wed, 2 Sep 2020 15:22:34 +1200 (NZST) Received: by pauld-dl.ws.atlnz.lc (Postfix, from userid 1684) id 14FC51E05C4; Wed, 2 Sep 2020 15:22:35 +1200 (NZST) From: Paul Davey To: "David S. Miller" Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Paul Davey Subject: [PATCH net-next 0/2] Allow more than 255 IPv4 multicast interfaces Date: Wed, 2 Sep 2020 15:22:20 +1200 Message-Id: <20200902032222.25109-1-paul.davey@alliedtelesis.co.nz> X-Mailer: git-send-email 2.28.0 MIME-Version: 1.0 x-atlnz-ls: pat Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Currently it is not possible to use more than 255 multicast interfaces for IPv4 due to the format of the igmpmsg header which only has 8 bits available for the VIF ID. There is enough space for the full VIF ID in the Netlink cache notifications, however the value is currently taken directly from the igmpmsg header and has thus already been truncated. Using the full VIF ID in the Netlink notifications allows use of more than 255 IPv4 multicast interfaces if the user space routing daemon uses the Netlink notifications instead of the igmpmsg cache reports. However doing this reveals a deficiency in the Netlink cache report notifications, they lack any means for differentiating cache reports relating to different multicast routing tables. This is easily resolved by adding the multicast route table ID to the cache reports. Paul Davey (2): ipmr: Add route table ID to netlink cache reports ipmr: Use full VIF ID in netlink cache reports include/uapi/linux/mroute.h | 1 + net/ipv4/ipmr.c | 12 +++++++----- 2 files changed, 8 insertions(+), 5 deletions(-)