From: Linus Lüssing Date: Fri, 15 Nov 2013 10:25:45 +0100 Subject: batman-adv: Add no-rebroadcast patch Adds a patch for batman-adv which allows us to disable rebroadcasts of multicast "payload" frames on the incoming interface for specific interfaces. diff --git a/batman-adv/files/lib/netifd/proto/batadv.sh b/batman-adv/files/lib/netifd/proto/batadv.sh index 632a209..01f567f 100644 --- a/batman-adv/files/lib/netifd/proto/batadv.sh +++ b/batman-adv/files/lib/netifd/proto/batadv.sh @@ -6,16 +6,19 @@ init_proto "$@" proto_batadv_init_config() { proto_config_add_string "mesh" + proto_config_add_string "mesh_no_rebroadcast" } proto_batadv_setup() { local config="$1" local iface="$2" - local mesh - json_get_vars mesh + local mesh mesh_no_rebroadcast + json_get_vars mesh mesh_no_rebroadcast echo "$mesh" > "/sys/class/net/$iface/batman_adv/mesh_iface" + [ -n "$mesh_no_rebroadcast" ] && echo "$mesh_no_rebroadcast" > "/sys/class/net/$iface/batman_adv/no_rebroadcast" + proto_init_update "$iface" 1 proto_send_update "$config" } diff --git a/batman-adv/patches/0001-batman-adv-introduce-no_rebroadcast-option.patch b/batman-adv/patches/0001-batman-adv-introduce-no_rebroadcast-option.patch new file mode 100644 index 0000000..db42f83 --- /dev/null +++ b/batman-adv/patches/0001-batman-adv-introduce-no_rebroadcast-option.patch @@ -0,0 +1,184 @@ +From 2bf08efc923da85b00354d5dcba6cddc6a8c09ce Mon Sep 17 00:00:00 2001 +From: =?UTF-8?q?Linus=20L=C3=BCssing?= +Date: Tue, 24 Sep 2013 04:36:27 +0200 +Subject: [PATCH] batman-adv: introduce 'no_rebroadcast' option +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +This patch introduces a new sysfs option named "no_rebroadcast" on +a per hard interface basis. It allows manually enabling a split-horizon +like behaviour for the layer 2 multicast payload frames, in that +incoming multicast payload frames on such a hard interface are only +being rebroadcasted on all interfaces except the incoming one instead +of being rebroadcasted on all interfaces. + +Such an option should only be enabled if you are certain that these +rebroadcasts are unnecessary. This is usually the case for instance +for point-to-point wifi longshots or wired links. + +This option can especially safe a significant amount of upload overhead +if the neighbourhood on a link is rather large, for instance in some +transitive, symmetric VPN configurations. + +Using this option wrongly will break your mesh network, use this option +wisely and at your own risk! + +Signed-off-by: Linus Lüssing +--- + hard-interface.c | 2 ++ + send.c | 4 +++ + sysfs-class-net-batman-adv | 10 ++++++++ + sysfs.c | 59 ++++++++++++++++++++++++++++++++++++++++++++ + types.h | 1 + + 5 files changed, 76 insertions(+) + +diff --git a/hard-interface.c b/hard-interface.c +index c478e6b..e0afd19 100644 +--- a/hard-interface.c ++++ b/hard-interface.c +@@ -600,6 +600,8 @@ batadv_hardif_add_interface(struct net_device *net_dev) + /* extra reference for return */ + atomic_set(&hard_iface->refcount, 2); + ++ atomic_set(&hard_iface->no_rebroadcast, 0); ++ + batadv_check_known_mac_addr(hard_iface->net_dev); + list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list); + +diff --git a/send.c b/send.c +index e9ff8d8..05287e6 100644 +--- a/send.c ++++ b/send.c +@@ -272,6 +272,10 @@ static void batadv_send_outstanding_bcast_packet(struct work_struct *work) + if (forw_packet->num_packets >= hard_iface->num_bcasts) + continue; + ++ if (atomic_read(&hard_iface->no_rebroadcast) && ++ forw_packet->skb->dev == hard_iface->net_dev) ++ continue; ++ + /* send a copy of the saved skb */ + skb1 = skb_clone(forw_packet->skb, GFP_ATOMIC); + if (skb1) +diff --git a/sysfs-class-net-batman-adv b/sysfs-class-net-batman-adv +index bdc0070..88f6f70 100644 +--- a/sysfs-class-net-batman-adv ++++ b/sysfs-class-net-batman-adv +@@ -13,3 +13,13 @@ Description: + displays the batman mesh interface this + currently is associated with. + ++What: /sys/class/net//batman-adv/no_rebroadcast ++Date: Sep 2013 ++Contact: Linus Lüssing ++Description: ++ With this option set incoming multicast payload frames on ++ are not being rebroadcasted on again. This ++ option should be set on links which are known to be transitive ++ and symmetric only, for instance point-to-point wifi longshots ++ or wired links. Using this option wrongly is going to ++ break your mesh network, use at your own risk! +diff --git a/sysfs.c b/sysfs.c +index 929e304..19e0930 100644 +--- a/sysfs.c ++++ b/sysfs.c +@@ -53,6 +53,17 @@ static char *batadv_uev_type_str[] = { + "gw" + }; + ++/* Use this, if you have customized show and store functions ++ * for hard interface attrs ++ */ ++#define BATADV_ATTR_HIF(_name, _mode, _show, _store) \ ++struct batadv_attribute batadv_attr_hif_##_name = { \ ++ .attr = {.name = __stringify(_name), \ ++ .mode = _mode }, \ ++ .show = _show, \ ++ .store = _store, \ ++}; ++ + /* Use this, if you have customized show and store functions */ + #define BATADV_ATTR(_name, _mode, _show, _store) \ + struct batadv_attribute batadv_attr_##_name = { \ +@@ -123,6 +134,52 @@ ssize_t batadv_show_##_name(struct kobject *kobj, \ + batadv_store_##_name) + + ++#define BATADV_ATTR_HIF_STORE_BOOL(_name, _post_func) \ ++ssize_t batadv_store_hif_##_name(struct kobject *kobj, \ ++ struct attribute *attr, char *buff, \ ++ size_t count) \ ++{ \ ++ struct net_device *net_dev = batadv_kobj_to_netdev(kobj); \ ++ struct batadv_hard_iface *hard_iface; \ ++ size_t res; \ ++ \ ++ hard_iface = batadv_hardif_get_by_netdev(net_dev); \ ++ if (!hard_iface) \ ++ return 0; \ ++ \ ++ res = __batadv_store_bool_attr(buff, count, _post_func, \ ++ attr, &hard_iface->_name, \ ++ hard_iface->soft_iface); \ ++ batadv_hardif_free_ref(hard_iface); \ ++ return res; \ ++} ++ ++#define BATADV_ATTR_HIF_SHOW_BOOL(_name) \ ++ssize_t batadv_show_hif_##_name(struct kobject *kobj, \ ++ struct attribute *attr, char *buff) \ ++{ \ ++ struct net_device *net_dev = batadv_kobj_to_netdev(kobj); \ ++ struct batadv_hard_iface *hard_iface; \ ++ size_t res; \ ++ \ ++ hard_iface = batadv_hardif_get_by_netdev(net_dev); \ ++ if (!hard_iface) \ ++ return 0; \ ++ \ ++ res = sprintf(buff, "%s\n", \ ++ atomic_read(&hard_iface->_name) == 0 ? \ ++ "disabled" : "enabled"); \ ++ batadv_hardif_free_ref(hard_iface); \ ++ return res; \ ++} ++ ++/* Use this, if you are going to turn a [name] in the vlan struct on or off */ ++#define BATADV_ATTR_HIF_BOOL(_name, _mode, _post_func) \ ++ static BATADV_ATTR_HIF_STORE_BOOL(_name, _post_func) \ ++ static BATADV_ATTR_HIF_SHOW_BOOL(_name) \ ++ static BATADV_ATTR_HIF(_name, _mode, batadv_show_hif_##_name, \ ++ batadv_store_hif_##_name) ++ + static int batadv_store_bool_attr(char *buff, size_t count, + struct net_device *net_dev, + const char *attr_name, atomic_t *attr) +@@ -642,10 +699,12 @@ static ssize_t batadv_show_iface_status(struct kobject *kobj, + static BATADV_ATTR(mesh_iface, S_IRUGO | S_IWUSR, batadv_show_mesh_iface, + batadv_store_mesh_iface); + static BATADV_ATTR(iface_status, S_IRUGO, batadv_show_iface_status, NULL); ++BATADV_ATTR_HIF_BOOL(no_rebroadcast, S_IRUGO | S_IWUSR, NULL); + + static struct batadv_attribute *batadv_batman_attrs[] = { + &batadv_attr_mesh_iface, + &batadv_attr_iface_status, ++ &batadv_attr_hif_no_rebroadcast, + NULL, + }; + +diff --git a/types.h b/types.h +index b2c94e1..d1e1bb9 100644 +--- a/types.h ++++ b/types.h +@@ -85,6 +85,7 @@ struct batadv_hard_iface { + struct rcu_head rcu; + struct batadv_hard_iface_bat_iv bat_iv; + struct work_struct cleanup_work; ++ atomic_t no_rebroadcast; + }; + + /** +-- +1.7.10.4 +