From patchwork Sun May 9 19:45:09 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Linus_L=C3=BCssing?= X-Patchwork-Id: 433492 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 43702C433ED for ; Sun, 9 May 2021 19:45:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2A3CC613AB for ; Sun, 9 May 2021 19:45:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230246AbhEITq6 (ORCPT ); Sun, 9 May 2021 15:46:58 -0400 Received: from mail.aperture-lab.de ([116.203.183.178]:56020 "EHLO mail.aperture-lab.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229987AbhEITqh (ORCPT ); Sun, 9 May 2021 15:46:37 -0400 Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 5BFED3EDDE; Sun, 9 May 2021 21:45:32 +0200 (CEST) From: =?utf-8?q?Linus_L=C3=BCssing?= To: netdev@vger.kernel.org Cc: Roopa Prabhu , Nikolay Aleksandrov , Jakub Kicinski , "David S . Miller" , bridge@lists.linux-foundation.org, b.a.t.m.a.n@lists.open-mesh.org, linux-kernel@vger.kernel.org, =?utf-8?q?Linus_L=C3=BCssing?= Subject: [net-next v2 11/11] net: bridge: mcast: export multicast router presence adjacent to a port Date: Sun, 9 May 2021 21:45:09 +0200 Message-Id: <20210509194509.10849-12-linus.luessing@c0d3.blue> In-Reply-To: <20210509194509.10849-1-linus.luessing@c0d3.blue> References: <20210509194509.10849-1-linus.luessing@c0d3.blue> MIME-Version: 1.0 X-Last-TLS-Session-Version: TLSv1.2 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org To properly support routable multicast addresses in batman-adv in a group-aware way, a batman-adv node needs to know if it serves multicast routers. This adds a function to the bridge to export this so that batman-adv can then make full use of the Multicast Router Discovery capability of the bridge. Signed-off-by: Linus Lüssing --- net/bridge/br_multicast.c | 58 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index b625fd6..e963de5 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -4061,6 +4061,64 @@ unlock: } EXPORT_SYMBOL_GPL(br_multicast_has_querier_adjacent); +/** + * br_multicast_has_router_adjacent - Checks for a router behind a bridge port + * @dev: The bridge port adjacent to which to check for a multicast router + * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6 + * + * Checks whether the given interface has a bridge on top and if so returns + * true if a multicast router is behind one of the other ports of this + * bridge. Otherwise returns false. + */ +bool br_multicast_has_router_adjacent(struct net_device *dev, int proto) +{ + struct net_bridge_port *port, *p; + bool ret = false; + + rcu_read_lock(); + if (!netif_is_bridge_port(dev)) + goto unlock; + + port = br_port_get_rcu(dev); + if (!port || !port->br) + goto unlock; + + switch (proto) { + case ETH_P_IP: + hlist_for_each_entry_rcu(p, &port->br->ip4_mc_router_list, + ip4_rlist) { + if (p == port) + continue; + + ret = true; + goto unlock; + } + break; +#if IS_ENABLED(CONFIG_IPV6) + case ETH_P_IPV6: + hlist_for_each_entry_rcu(p, &port->br->ip6_mc_router_list, + ip6_rlist) { + if (p == port) + continue; + + ret = true; + goto unlock; + } + break; +#endif + default: + /* when compiled without IPv6 support, be conservative and + * always assume presence of an IPv6 multicast router + */ + ret = true; + } + +unlock: + rcu_read_unlock(); + return ret; +} +EXPORT_SYMBOL_GPL(br_multicast_has_router_adjacent); + static void br_mcast_stats_add(struct bridge_mcast_stats __percpu *stats, const struct sk_buff *skb, u8 type, u8 dir) {