From patchwork Wed May 21 08:59:00 2014 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: 4054 Return-Path: Received: from mout.web.de (mout.web.de [212.227.15.3]) by open-mesh.org (Postfix) with ESMTPS id 3818C600B35 for ; Wed, 21 May 2014 10:58:56 +0200 (CEST) Received: from localhost ([85.17.31.120]) by smtp.web.de (mrweb101) with ESMTPSA (Nemesis) id 0MBCBN-1WdNrC35HB-00AEXO; Wed, 21 May 2014 10:58:43 +0200 From: =?UTF-8?q?Linus=20L=C3=BCssing?= To: netdev@vger.kernel.org Date: Wed, 21 May 2014 10:59:00 +0200 Message-Id: <1400662742-31999-3-git-send-email-linus.luessing@web.de> X-Mailer: git-send-email 2.0.0.rc2 In-Reply-To: <1400662742-31999-1-git-send-email-linus.luessing@web.de> References: <1400662742-31999-1-git-send-email-linus.luessing@web.de> MIME-Version: 1.0 X-Provags-ID: V03:K0:UFgiFNUZmTt1SO57s7XYuKHZsKVnNJJUv0UKdrg0uXkq7CAV8Ta HDDNC1kyd8IQSq1wi6Tur1nOMvVl0kf+ow3rZpVumstdNArm5pzYINM3zTS0t1VkYl/ZLZl PG9+OomVBAtA5n6/cCPPgb7K6swbyk9dG492rxeMiNbrbFATZzrlGDWti4OgUGQ4FPMtmXK IZYvnx3ff3kxD9C0ABmug== Cc: b.a.t.m.a.n@lists.open-mesh.org, bridge@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Stephen Hemminger , "David S. Miller" Subject: [B.A.T.M.A.N.] [PATCH net-next 2/4] bridge: adhere to querier election mechanism specified by RFCs X-BeenThere: b.a.t.m.a.n@lists.open-mesh.org X-Mailman-Version: 2.1.15 Precedence: list Reply-To: The list for a Better Approach To Mobile Ad-hoc Networking List-Id: The list for a Better Approach To Mobile Ad-hoc Networking List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 21 May 2014 08:58:56 -0000 MLDv1 (RFC2710 section 6), MLDv2 (RFC3810 section 7.6.2), IGMPv2 (RFC2236 section 3) and IGMPv3 (RFC3376 section 6.6.2) specify that the querier with lowest source address shall become the selected querier. So far the bridge stopped its querier as soon as it heard another querier regardless of its source address. This results in the "wrong" querier potentially becoming the active querier or a potential, unnecessary querying delay. With this patch the bridge memorizes the source address of the currently selected querier and ignores queries from queriers with a higher source address than the currently selected one. This slight optimization is supposed to make it more RFC compliant (but is rather uncritical and therefore probably not necessary to be queued for stable kernels). Signed-off-by: Linus Lüssing --- net/bridge/br_multicast.c | 101 +++++++++++++++++++++++++++++++++++++++------ net/bridge/br_private.h | 7 ++++ 2 files changed, 95 insertions(+), 13 deletions(-) diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 6bc9cef..05c6593 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -789,6 +789,18 @@ static void br_ip6_multicast_querier_expired(unsigned long data) } #endif +static void br_multicast_select_own_querier(struct net_bridge *br, + struct br_ip *ip, + struct sk_buff *skb) +{ + if (ip->proto == htons(ETH_P_IP)) + br->ip4_querier.addr.u.ip4 = ip_hdr(skb)->saddr; +#if IS_ENABLED(CONFIG_IPV6) + else + br->ip6_querier.addr.u.ip6 = ipv6_hdr(skb)->saddr; +#endif +} + static void __br_multicast_send_query(struct net_bridge *br, struct net_bridge_port *port, struct br_ip *ip) @@ -804,8 +816,10 @@ static void __br_multicast_send_query(struct net_bridge *br, skb->dev = port->dev; NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev, dev_queue_xmit); - } else + } else { + br_multicast_select_own_querier(br, ip, skb); netif_rx(skb); + } } static void br_multicast_send_query(struct net_bridge *br, @@ -1065,6 +1079,62 @@ static int br_ip6_multicast_mld2_report(struct net_bridge *br, } #endif +static bool br_ip4_multicast_select_querier(struct net_bridge *br, + __be32 saddr) +{ + if (!timer_pending(&br->ip4_own_query.timer) && + !timer_pending(&br->ip4_other_query.timer)) + goto update; + + if (!br->ip4_querier.addr.u.ip4) + goto update; + + if (saddr <= br->ip4_querier.addr.u.ip4) + goto update; + + return false; + +update: + br->ip4_querier.addr.u.ip4 = saddr; + + return true; +} + +#if IS_ENABLED(CONFIG_IPV6) +static bool br_ip6_multicast_select_querier(struct net_bridge *br, + struct in6_addr *saddr) +{ + if (!timer_pending(&br->ip6_own_query.timer) && + !timer_pending(&br->ip6_other_query.timer)) + goto update; + + if (ipv6_addr_cmp(saddr, &br->ip6_querier.addr.u.ip6) <= 0) + goto update; + + return false; + +update: + br->ip6_querier.addr.u.ip6 = *saddr; + + return true; +} +#endif + +static bool br_multicast_select_querier(struct net_bridge *br, + struct br_ip *saddr) +{ + switch (saddr->proto) { + case htons(ETH_P_IP): + return br_ip4_multicast_select_querier(br, saddr->u.ip4); +#if IS_ENABLED(CONFIG_IPV6) + case htons(ETH_P_IPV6): + return br_ip6_multicast_select_querier(br, &saddr->u.ip6); +#endif + } + + return false; +} + static void br_multicast_update_query_timer(struct net_bridge *br, struct bridge_mcast_other_query *query, @@ -1127,15 +1197,13 @@ timer: static void br_multicast_query_received(struct net_bridge *br, struct net_bridge_port *port, struct bridge_mcast_other_query *query, - int saddr, - bool is_general_query, + struct br_ip *saddr, unsigned long max_delay) { - if (saddr && is_general_query) - br_multicast_update_query_timer(br, query, max_delay); - else if (timer_pending(&query->timer)) + if (!br_multicast_select_querier(br, saddr)) return; + br_multicast_update_query_timer(br, query, max_delay); br_multicast_mark_router(br, port); } @@ -1150,6 +1218,7 @@ static int br_ip4_multicast_query(struct net_bridge *br, struct igmpv3_query *ih3; struct net_bridge_port_group *p; struct net_bridge_port_group __rcu **pp; + struct br_ip saddr; unsigned long max_delay; unsigned long now = jiffies; __be32 group; @@ -1191,11 +1260,14 @@ static int br_ip4_multicast_query(struct net_bridge *br, goto out; } - br_multicast_query_received(br, port, &br->ip4_other_query, - !!iph->saddr, !group, max_delay); + if (!group) { + saddr.proto = ntohs(ETH_P_IP); + saddr.u.ip4 = iph->saddr; - if (!group) + br_multicast_query_received(br, port, &br->ip4_other_query, + &saddr, max_delay); goto out; + } mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid); if (!mp) @@ -1235,6 +1307,7 @@ static int br_ip6_multicast_query(struct net_bridge *br, struct mld2_query *mld2q; struct net_bridge_port_group *p; struct net_bridge_port_group __rcu **pp; + struct br_ip saddr; unsigned long max_delay; unsigned long now = jiffies; const struct in6_addr *group = NULL; @@ -1283,12 +1356,14 @@ static int br_ip6_multicast_query(struct net_bridge *br, goto out; } - br_multicast_query_received(br, port, &br->ip6_other_query, - !ipv6_addr_any(&ip6h->saddr), - is_general_query, max_delay); + if (is_general_query) { + saddr.proto = ntohs(ETH_P_IPV6); + saddr.u.ip6 = ip6h->saddr; - if (!group) + br_multicast_query_received(br, port, &br->ip6_other_query, + &saddr, max_delay); goto out; + } mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid); if (!mp) diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index f186ce8..bc1803b 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -78,6 +78,11 @@ struct bridge_mcast_other_query { struct timer_list timer; unsigned long delay_time; }; + +/* selected querier */ +struct bridge_mcast_querier { + struct br_ip addr; +}; #endif struct net_port_vlans { @@ -284,9 +289,11 @@ struct net_bridge struct timer_list multicast_router_timer; struct bridge_mcast_other_query ip4_other_query; struct bridge_mcast_own_query ip4_own_query; + struct bridge_mcast_querier ip4_querier; #if IS_ENABLED(CONFIG_IPV6) struct bridge_mcast_other_query ip6_other_query; struct bridge_mcast_own_query ip6_own_query; + struct bridge_mcast_querier ip6_querier; #endif /* IS_ENABLED(CONFIG_IPV6) */ #endif