From 61caf3d109f5411a7f5b433f1eb73ead7e0789fa Mon Sep 17 00:00:00 2001 From: Linus Lüssing Date: Tue, 11 Jun 2019 22:58:40 +0200 Subject: batman-adv: mcast: detect, distribute and maintain multicast router presence MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit To be able to apply our group aware multicast optimizations to packets with a scope greater than link-local we need to not only keep track of multicast listeners but also multicast routers. With this patch a node detects the presence of multicast routers on its segment by checking if /proc/sys/net/ipv{4,6}/conf//mc_forwarding is set for one thing. This option is enabled by multicast routing daemons and needed for the kernel's multicast routing tables to receive and route packets. For another thing if a bridge is configured on top of bat0 then the presence of an IPv6 multicast router behind this bridge is currently detected by checking for an IPv6 multicast "All Routers Address" (ff02::2). This should later be replaced by querying the bridge, which performs proper, RFC4286 compliant Multicast Router Discovery (our simplified approach includes more hosts than necessary, most notably not just multicast routers but also unicast ones and is not applicable for IPv4). If no multicast router is detected then this is signalized via the new BATADV_MCAST_WANT_NO_RTR4 and BATADV_MCAST_WANT_NO_RTR6 multicast tvlv flags. Signed-off-by: Linus Lüssing Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich --- net/batman-adv/types.h | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) (limited to 'net/batman-adv/types.h') diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 72f65b3769d0..c2996296b953 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -404,6 +404,17 @@ struct batadv_orig_node { * list */ struct hlist_node mcast_want_all_ipv6_node; + + /** + * @mcast_want_all_rtr4_node: a list node for the mcast.want_all_rtr4 + * list + */ + struct hlist_node mcast_want_all_rtr4_node; + /** + * @mcast_want_all_rtr6_node: a list node for the mcast.want_all_rtr6 + * list + */ + struct hlist_node mcast_want_all_rtr6_node; #endif /** @capabilities: announced capabilities of this originator */ @@ -1218,6 +1229,18 @@ struct batadv_priv_mcast { */ struct hlist_head want_all_ipv6_list; + /** + * @want_all_rtr4_list: a list of orig_nodes wanting all routable IPv4 + * multicast traffic + */ + struct hlist_head want_all_rtr4_list; + + /** + * @want_all_rtr6_list: a list of orig_nodes wanting all routable IPv6 + * multicast traffic + */ + struct hlist_head want_all_rtr6_list; + /** * @mla_flags: flags for the querier, bridge and tvlv state */ @@ -1240,6 +1263,12 @@ struct batadv_priv_mcast { /** @num_want_all_ipv6: counter for items in want_all_ipv6_list */ atomic_t num_want_all_ipv6; + /** @num_want_all_rtr4: counter for items in want_all_rtr4_list */ + atomic_t num_want_all_rtr4; + + /** @num_want_all_rtr6: counter for items in want_all_rtr6_list */ + atomic_t num_want_all_rtr6; + /** * @want_lists_lock: lock for protecting modifications to mcasts * want_all_{unsnoopables,ipv4,ipv6}_list (traversals are rcu-locked) -- cgit v1.2.3-59-g8ed1b