From c5caf4ef34e2779c9a90bf4cbb57fbdf57dc8cbc Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Linus=20L=C3=BCssing?= Date: Sat, 15 Feb 2014 17:47:49 +0100 Subject: batman-adv: Multicast Listener Announcements via Translation Table MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit With this patch a node which has no bridge interface on top of its soft interface announces its local multicast listeners via the translation table. Signed-off-by: Linus Lüssing Signed-off-by: Marek Lindner Signed-off-by: Antonio Quartulli --- net/batman-adv/multicast.c | 218 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 218 insertions(+) create mode 100644 net/batman-adv/multicast.c (limited to 'net/batman-adv/multicast.c') diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c new file mode 100644 index 000000000000..e099fd67403c --- /dev/null +++ b/net/batman-adv/multicast.c @@ -0,0 +1,218 @@ +/* Copyright (C) 2014 B.A.T.M.A.N. contributors: + * + * Linus Lüssing + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ + +#include "main.h" +#include "multicast.h" +#include "originator.h" +#include "hard-interface.h" +#include "translation-table.h" + +/** + * batadv_mcast_mla_softif_get - get softif multicast listeners + * @dev: the device to collect multicast addresses from + * @mcast_list: a list to put found addresses into + * + * Collect multicast addresses of the local multicast listeners + * on the given soft interface, dev, in the given mcast_list. + * + * Returns -ENOMEM on memory allocation error or the number of + * items added to the mcast_list otherwise. + */ +static int batadv_mcast_mla_softif_get(struct net_device *dev, + struct hlist_head *mcast_list) +{ + struct netdev_hw_addr *mc_list_entry; + struct batadv_hw_addr *new; + int ret = 0; + + netif_addr_lock_bh(dev); + netdev_for_each_mc_addr(mc_list_entry, dev) { + new = kmalloc(sizeof(*new), GFP_ATOMIC); + if (!new) { + ret = -ENOMEM; + break; + } + + ether_addr_copy(new->addr, mc_list_entry->addr); + hlist_add_head(&new->list, mcast_list); + ret++; + } + netif_addr_unlock_bh(dev); + + return ret; +} + +/** + * batadv_mcast_mla_is_duplicate - check whether an address is in a list + * @mcast_addr: the multicast address to check + * @mcast_list: the list with multicast addresses to search in + * + * Returns true if the given address is already in the given list. + * Otherwise returns false. + */ +static bool batadv_mcast_mla_is_duplicate(uint8_t *mcast_addr, + struct hlist_head *mcast_list) +{ + struct batadv_hw_addr *mcast_entry; + + hlist_for_each_entry(mcast_entry, mcast_list, list) + if (batadv_compare_eth(mcast_entry->addr, mcast_addr)) + return true; + + return false; +} + +/** + * batadv_mcast_mla_list_free - free a list of multicast addresses + * @mcast_list: the list to free + * + * Removes and frees all items in the given mcast_list. + */ +static void batadv_mcast_mla_list_free(struct hlist_head *mcast_list) +{ + struct batadv_hw_addr *mcast_entry; + struct hlist_node *tmp; + + hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) { + hlist_del(&mcast_entry->list); + kfree(mcast_entry); + } +} + +/** + * batadv_mcast_mla_tt_retract - clean up multicast listener announcements + * @bat_priv: the bat priv with all the soft interface information + * @mcast_list: a list of addresses which should _not_ be removed + * + * Retracts the announcement of any multicast listener from the + * translation table except the ones listed in the given mcast_list. + * + * If mcast_list is NULL then all are retracted. + */ +static void batadv_mcast_mla_tt_retract(struct batadv_priv *bat_priv, + struct hlist_head *mcast_list) +{ + struct batadv_hw_addr *mcast_entry; + struct hlist_node *tmp; + + hlist_for_each_entry_safe(mcast_entry, tmp, &bat_priv->mcast.mla_list, + list) { + if (mcast_list && + batadv_mcast_mla_is_duplicate(mcast_entry->addr, + mcast_list)) + continue; + + batadv_tt_local_remove(bat_priv, mcast_entry->addr, + BATADV_NO_FLAGS, + "mcast TT outdated", false); + + hlist_del(&mcast_entry->list); + kfree(mcast_entry); + } +} + +/** + * batadv_mcast_mla_tt_add - add multicast listener announcements + * @bat_priv: the bat priv with all the soft interface information + * @mcast_list: a list of addresses which are going to get added + * + * Adds multicast listener announcements from the given mcast_list to the + * translation table if they have not been added yet. + */ +static void batadv_mcast_mla_tt_add(struct batadv_priv *bat_priv, + struct hlist_head *mcast_list) +{ + struct batadv_hw_addr *mcast_entry; + struct hlist_node *tmp; + + if (!mcast_list) + return; + + hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) { + if (batadv_mcast_mla_is_duplicate(mcast_entry->addr, + &bat_priv->mcast.mla_list)) + continue; + + if (!batadv_tt_local_add(bat_priv->soft_iface, + mcast_entry->addr, BATADV_NO_FLAGS, + BATADV_NULL_IFINDEX, BATADV_NO_MARK)) + continue; + + hlist_del(&mcast_entry->list); + hlist_add_head(&mcast_entry->list, &bat_priv->mcast.mla_list); + } +} + +/** + * batadv_mcast_has_bridge - check whether the soft-iface is bridged + * @bat_priv: the bat priv with all the soft interface information + * + * Checks whether there is a bridge on top of our soft interface. Returns + * true if so, false otherwise. + */ +static bool batadv_mcast_has_bridge(struct batadv_priv *bat_priv) +{ + struct net_device *upper = bat_priv->soft_iface; + + rcu_read_lock(); + do { + upper = netdev_master_upper_dev_get_rcu(upper); + } while (upper && !(upper->priv_flags & IFF_EBRIDGE)); + rcu_read_unlock(); + + return upper; +} + +/** + * batadv_mcast_mla_update - update the own MLAs + * @bat_priv: the bat priv with all the soft interface information + * + * Update the own multicast listener announcements in the translation + * table. + */ +void batadv_mcast_mla_update(struct batadv_priv *bat_priv) +{ + struct net_device *soft_iface = bat_priv->soft_iface; + struct hlist_head mcast_list = HLIST_HEAD_INIT; + int ret; + + /* Avoid attaching MLAs, if there is a bridge on top of our soft + * interface, we don't support that yet (TODO) + */ + if (batadv_mcast_has_bridge(bat_priv)) + goto update; + + ret = batadv_mcast_mla_softif_get(soft_iface, &mcast_list); + if (ret < 0) + goto out; + +update: + batadv_mcast_mla_tt_retract(bat_priv, &mcast_list); + batadv_mcast_mla_tt_add(bat_priv, &mcast_list); + +out: + batadv_mcast_mla_list_free(&mcast_list); +} + +/** + * batadv_mcast_free - free the multicast optimizations structures + * @bat_priv: the bat priv with all the soft interface information + */ +void batadv_mcast_free(struct batadv_priv *bat_priv) +{ + batadv_mcast_mla_tt_retract(bat_priv, NULL); +} -- cgit v1.2.3 From 60432d756cf06e597ef9da511402dd059b112447 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Linus=20L=C3=BCssing?= Date: Sat, 15 Feb 2014 17:47:51 +0100 Subject: batman-adv: Announce new capability via multicast TVLV MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If the soft interface of a node is not part of a bridge then a node announces a new multicast TVLV: The existence of this TVLV signalizes that this node is announcing all of its multicast listeners via the translation table infrastructure. Signed-off-by: Linus Lüssing Signed-off-by: Marek Lindner Signed-off-by: Antonio Quartulli --- net/batman-adv/multicast.c | 123 ++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 117 insertions(+), 6 deletions(-) (limited to 'net/batman-adv/multicast.c') diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c index e099fd67403c..3ba9a18a906c 100644 --- a/net/batman-adv/multicast.c +++ b/net/batman-adv/multicast.c @@ -177,12 +177,53 @@ static bool batadv_mcast_has_bridge(struct batadv_priv *bat_priv) return upper; } +/** + * batadv_mcast_mla_tvlv_update - update multicast tvlv + * @bat_priv: the bat priv with all the soft interface information + * + * Updates the own multicast tvlv with our current multicast related settings, + * capabilities and inabilities. + * + * Returns true if the tvlv container is registered afterwards. Otherwise + * returns false. + */ +static bool batadv_mcast_mla_tvlv_update(struct batadv_priv *bat_priv) +{ + struct batadv_tvlv_mcast_data mcast_data; + + mcast_data.flags = BATADV_NO_FLAGS; + memset(mcast_data.reserved, 0, sizeof(mcast_data.reserved)); + + /* Avoid attaching MLAs, if there is a bridge on top of our soft + * interface, we don't support that yet (TODO) + */ + if (batadv_mcast_has_bridge(bat_priv)) { + if (bat_priv->mcast.enabled) { + batadv_tvlv_container_unregister(bat_priv, + BATADV_TVLV_MCAST, 1); + bat_priv->mcast.enabled = false; + } + + return false; + } + + if (!bat_priv->mcast.enabled || + mcast_data.flags != bat_priv->mcast.flags) { + batadv_tvlv_container_register(bat_priv, BATADV_TVLV_MCAST, 1, + &mcast_data, sizeof(mcast_data)); + bat_priv->mcast.flags = mcast_data.flags; + bat_priv->mcast.enabled = true; + } + + return true; +} + /** * batadv_mcast_mla_update - update the own MLAs * @bat_priv: the bat priv with all the soft interface information * - * Update the own multicast listener announcements in the translation - * table. + * Updates the own multicast listener announcements in the translation + * table as well as the own, announced multicast tvlv container. */ void batadv_mcast_mla_update(struct batadv_priv *bat_priv) { @@ -190,10 +231,7 @@ void batadv_mcast_mla_update(struct batadv_priv *bat_priv) struct hlist_head mcast_list = HLIST_HEAD_INIT; int ret; - /* Avoid attaching MLAs, if there is a bridge on top of our soft - * interface, we don't support that yet (TODO) - */ - if (batadv_mcast_has_bridge(bat_priv)) + if (!batadv_mcast_mla_tvlv_update(bat_priv)) goto update; ret = batadv_mcast_mla_softif_get(soft_iface, &mcast_list); @@ -208,11 +246,84 @@ out: batadv_mcast_mla_list_free(&mcast_list); } +/** + * batadv_mcast_tvlv_ogm_handler_v1 - process incoming multicast tvlv container + * @bat_priv: the bat priv with all the soft interface information + * @orig: the orig_node of the ogm + * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags) + * @tvlv_value: tvlv buffer containing the multicast data + * @tvlv_value_len: tvlv buffer length + */ +static void batadv_mcast_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv, + struct batadv_orig_node *orig, + uint8_t flags, + void *tvlv_value, + uint16_t tvlv_value_len) +{ + bool orig_mcast_enabled = !(flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND); + uint8_t mcast_flags = BATADV_NO_FLAGS; + bool orig_initialized; + + orig_initialized = orig->capa_initialized & BATADV_ORIG_CAPA_HAS_MCAST; + + /* If mcast support is turned on decrease the disabled mcast node + * counter only if we had increased it for this node before. If this + * is a completely new orig_node no need to decrease the counter. + */ + if (orig_mcast_enabled && + !(orig->capabilities & BATADV_ORIG_CAPA_HAS_MCAST)) { + if (orig_initialized) + atomic_dec(&bat_priv->mcast.num_disabled); + orig->capabilities |= BATADV_ORIG_CAPA_HAS_MCAST; + /* If mcast support is being switched off increase the disabled + * mcast node counter. + */ + } else if (!orig_mcast_enabled && + orig->capabilities & BATADV_ORIG_CAPA_HAS_MCAST) { + atomic_inc(&bat_priv->mcast.num_disabled); + orig->capabilities &= ~BATADV_ORIG_CAPA_HAS_MCAST; + } + + orig->capa_initialized |= BATADV_ORIG_CAPA_HAS_MCAST; + + if (orig_mcast_enabled && tvlv_value && + (tvlv_value_len >= sizeof(mcast_flags))) + mcast_flags = *(uint8_t *)tvlv_value; + + orig->mcast_flags = mcast_flags; +} + +/** + * batadv_mcast_init - initialize the multicast optimizations structures + * @bat_priv: the bat priv with all the soft interface information + */ +void batadv_mcast_init(struct batadv_priv *bat_priv) +{ + batadv_tvlv_handler_register(bat_priv, batadv_mcast_tvlv_ogm_handler_v1, + NULL, BATADV_TVLV_MCAST, 1, + BATADV_TVLV_HANDLER_OGM_CIFNOTFND); +} + /** * batadv_mcast_free - free the multicast optimizations structures * @bat_priv: the bat priv with all the soft interface information */ void batadv_mcast_free(struct batadv_priv *bat_priv) { + batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_MCAST, 1); + batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_MCAST, 1); + batadv_mcast_mla_tt_retract(bat_priv, NULL); } + +/** + * batadv_mcast_purge_orig - reset originator global mcast state modifications + * @orig: the originator which is going to get purged + */ +void batadv_mcast_purge_orig(struct batadv_orig_node *orig) +{ + struct batadv_priv *bat_priv = orig->bat_priv; + + if (!(orig->capabilities & BATADV_ORIG_CAPA_HAS_MCAST)) + atomic_dec(&bat_priv->mcast.num_disabled); +} -- cgit v1.2.3 From 1d8ab8d3c176d31530b3ffd4547cf731018e2a45 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Linus=20L=C3=BCssing?= Date: Sat, 15 Feb 2014 17:47:52 +0100 Subject: batman-adv: Modified forwarding behaviour for multicast packets MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit With this patch a multicast packet is not always simply flooded anymore, the behaviour for the following cases is changed to reduce unnecessary overhead: If all nodes within the horizon of a certain node have signalized multicast listener announcement capability then an IPv6 multicast packet with a destination of IPv6 link-local scope (excluding ff02::1) coming from the upstream of this node... * ...is dropped if there is no according multicast listener in the translation table, * ...is forwarded via unicast if there is a single node with interested multicast listeners * ...and otherwise still gets flooded. Signed-off-by: Linus Lüssing Signed-off-by: Marek Lindner Signed-off-by: Antonio Quartulli --- net/batman-adv/multicast.c | 126 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 126 insertions(+) (limited to 'net/batman-adv/multicast.c') diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c index 3ba9a18a906c..1d1627fe0de0 100644 --- a/net/batman-adv/multicast.c +++ b/net/batman-adv/multicast.c @@ -20,6 +20,7 @@ #include "originator.h" #include "hard-interface.h" #include "translation-table.h" +#include "multicast.h" /** * batadv_mcast_mla_softif_get - get softif multicast listeners @@ -246,6 +247,131 @@ out: batadv_mcast_mla_list_free(&mcast_list); } +/** + * batadv_mcast_forw_mode_check_ipv6 - check for optimized forwarding potential + * @bat_priv: the bat priv with all the soft interface information + * @skb: the IPv6 packet to check + * + * Checks whether the given IPv6 packet has the potential to be forwarded with a + * mode more optimal than classic flooding. + * + * If so then returns 0. Otherwise -EINVAL is returned or -ENOMEM if we are out + * of memory. + */ +static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv, + struct sk_buff *skb) +{ + struct ipv6hdr *ip6hdr; + + /* We might fail due to out-of-memory -> drop it */ + if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*ip6hdr))) + return -ENOMEM; + + ip6hdr = ipv6_hdr(skb); + + /* TODO: Implement Multicast Router Discovery (RFC4286), + * then allow scope > link local, too + */ + if (IPV6_ADDR_MC_SCOPE(&ip6hdr->daddr) != IPV6_ADDR_SCOPE_LINKLOCAL) + return -EINVAL; + + /* link-local-all-nodes multicast listeners behind a bridge are + * not snoopable (see RFC4541, section 3, paragraph 3) + */ + if (ipv6_addr_is_ll_all_nodes(&ip6hdr->daddr)) + return -EINVAL; + + return 0; +} + +/** + * batadv_mcast_forw_mode_check - check for optimized forwarding potential + * @bat_priv: the bat priv with all the soft interface information + * @skb: the multicast frame to check + * + * Checks whether the given multicast ethernet frame has the potential to be + * forwarded with a mode more optimal than classic flooding. + * + * If so then returns 0. Otherwise -EINVAL is returned or -ENOMEM if we are out + * of memory. + */ +static int batadv_mcast_forw_mode_check(struct batadv_priv *bat_priv, + struct sk_buff *skb) +{ + struct ethhdr *ethhdr = eth_hdr(skb); + + if (!atomic_read(&bat_priv->multicast_mode)) + return -EINVAL; + + if (atomic_read(&bat_priv->mcast.num_disabled)) + return -EINVAL; + + switch (ntohs(ethhdr->h_proto)) { + case ETH_P_IPV6: + return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb); + default: + return -EINVAL; + } +} + +/** + * batadv_mcast_forw_tt_node_get - get a multicast tt node + * @bat_priv: the bat priv with all the soft interface information + * @ethhdr: the ether header containing the multicast destination + * + * Returns an orig_node matching the multicast address provided by ethhdr + * via a translation table lookup. This increases the returned nodes refcount. + */ +static struct batadv_orig_node * +batadv_mcast_forw_tt_node_get(struct batadv_priv *bat_priv, + struct ethhdr *ethhdr) +{ + return batadv_transtable_search(bat_priv, ethhdr->h_source, + ethhdr->h_dest, BATADV_NO_FLAGS); +} + +/** + * batadv_mcast_forw_mode - check on how to forward a multicast packet + * @bat_priv: the bat priv with all the soft interface information + * @skb: The multicast packet to check + * @orig: an originator to be set to forward the skb to + * + * Returns the forwarding mode as enum batadv_forw_mode and in case of + * BATADV_FORW_SINGLE set the orig to the single originator the skb + * should be forwarded to. + */ +enum batadv_forw_mode +batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb, + struct batadv_orig_node **orig) +{ + struct ethhdr *ethhdr; + int ret, tt_count; + + ret = batadv_mcast_forw_mode_check(bat_priv, skb); + if (ret == -ENOMEM) + return BATADV_FORW_NONE; + else if (ret < 0) + return BATADV_FORW_ALL; + + ethhdr = eth_hdr(skb); + + tt_count = batadv_tt_global_hash_count(bat_priv, ethhdr->h_dest, + BATADV_NO_FLAGS); + + switch (tt_count) { + case 1: + *orig = batadv_mcast_forw_tt_node_get(bat_priv, ethhdr); + if (*orig) + return BATADV_FORW_SINGLE; + + /* fall through */ + case 0: + return BATADV_FORW_NONE; + default: + return BATADV_FORW_ALL; + } +} + /** * batadv_mcast_tvlv_ogm_handler_v1 - process incoming multicast tvlv container * @bat_priv: the bat priv with all the soft interface information -- cgit v1.2.3 From ab49886e3da73b6b35ece21006e191910427bb30 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Linus=20L=C3=BCssing?= Date: Sat, 15 Feb 2014 17:47:53 +0100 Subject: batman-adv: Add IPv4 link-local/IPv6-ll-all-nodes multicast support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit With this patch a node may additionally perform the dropping or unicasting behaviour for a link-local IPv4 and link-local-all-nodes IPv6 multicast packet, too. The extra counter and BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag is needed because with a future bridge snooping support integration a node with a bridge on top of its soft interface is not able to reliably detect its multicast listeners for IPv4 link-local and the IPv6 link-local-all-nodes addresses anymore (see RFC4541, section 2.1.2.2 and section 3). Even though this new flag does make "no difference" now, it'll ensure a seamless integration of multicast bridge support without needing to break compatibility later. Also note, that even with multicast bridge support it won't be possible to optimize 224.0.0.x and ff02::1 towards nodes with bridges, they will always receive these ranges. Signed-off-by: Linus Lüssing Signed-off-by: Marek Lindner Signed-off-by: Antonio Quartulli --- net/batman-adv/multicast.c | 135 ++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 127 insertions(+), 8 deletions(-) (limited to 'net/batman-adv/multicast.c') diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c index 1d1627fe0de0..a4804fa1ad11 100644 --- a/net/batman-adv/multicast.c +++ b/net/batman-adv/multicast.c @@ -247,10 +247,49 @@ out: batadv_mcast_mla_list_free(&mcast_list); } +/** + * batadv_mcast_forw_mode_check_ipv4 - check for optimized forwarding potential + * @bat_priv: the bat priv with all the soft interface information + * @skb: the IPv4 packet to check + * @is_unsnoopable: stores whether the destination is snoopable + * + * Checks whether the given IPv4 packet has the potential to be forwarded with a + * mode more optimal than classic flooding. + * + * If so then returns 0. Otherwise -EINVAL is returned or -ENOMEM in case of + * memory allocation failure. + */ +static int batadv_mcast_forw_mode_check_ipv4(struct batadv_priv *bat_priv, + struct sk_buff *skb, + bool *is_unsnoopable) +{ + struct iphdr *iphdr; + + /* We might fail due to out-of-memory -> drop it */ + if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*iphdr))) + return -ENOMEM; + + iphdr = ip_hdr(skb); + + /* TODO: Implement Multicast Router Discovery (RFC4286), + * then allow scope > link local, too + */ + if (!ipv4_is_local_multicast(iphdr->daddr)) + return -EINVAL; + + /* link-local multicast listeners behind a bridge are + * not snoopable (see RFC4541, section 2.1.2.2) + */ + *is_unsnoopable = true; + + return 0; +} + /** * batadv_mcast_forw_mode_check_ipv6 - check for optimized forwarding potential * @bat_priv: the bat priv with all the soft interface information * @skb: the IPv6 packet to check + * @is_unsnoopable: stores whether the destination is snoopable * * Checks whether the given IPv6 packet has the potential to be forwarded with a * mode more optimal than classic flooding. @@ -259,7 +298,8 @@ out: * of memory. */ static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv, - struct sk_buff *skb) + struct sk_buff *skb, + bool *is_unsnoopable) { struct ipv6hdr *ip6hdr; @@ -279,7 +319,7 @@ static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv, * not snoopable (see RFC4541, section 3, paragraph 3) */ if (ipv6_addr_is_ll_all_nodes(&ip6hdr->daddr)) - return -EINVAL; + *is_unsnoopable = true; return 0; } @@ -288,6 +328,7 @@ static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv, * batadv_mcast_forw_mode_check - check for optimized forwarding potential * @bat_priv: the bat priv with all the soft interface information * @skb: the multicast frame to check + * @is_unsnoopable: stores whether the destination is snoopable * * Checks whether the given multicast ethernet frame has the potential to be * forwarded with a mode more optimal than classic flooding. @@ -296,7 +337,8 @@ static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv, * of memory. */ static int batadv_mcast_forw_mode_check(struct batadv_priv *bat_priv, - struct sk_buff *skb) + struct sk_buff *skb, + bool *is_unsnoopable) { struct ethhdr *ethhdr = eth_hdr(skb); @@ -307,8 +349,12 @@ static int batadv_mcast_forw_mode_check(struct batadv_priv *bat_priv, return -EINVAL; switch (ntohs(ethhdr->h_proto)) { + case ETH_P_IP: + return batadv_mcast_forw_mode_check_ipv4(bat_priv, skb, + is_unsnoopable); case ETH_P_IPV6: - return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb); + return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb, + is_unsnoopable); default: return -EINVAL; } @@ -330,6 +376,33 @@ batadv_mcast_forw_tt_node_get(struct batadv_priv *bat_priv, ethhdr->h_dest, BATADV_NO_FLAGS); } +/** + * batadv_mcast_want_forw_unsnoop_node_get - get a node with an unsnoopable flag + * @bat_priv: the bat priv with all the soft interface information + * + * Returns an orig_node which has the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag + * set and increases its refcount. + */ +static struct batadv_orig_node * +batadv_mcast_forw_unsnoop_node_get(struct batadv_priv *bat_priv) +{ + struct batadv_orig_node *tmp_orig_node, *orig_node = NULL; + + rcu_read_lock(); + hlist_for_each_entry_rcu(tmp_orig_node, + &bat_priv->mcast.want_all_unsnoopables_list, + mcast_want_all_unsnoopables_node) { + if (!atomic_inc_not_zero(&orig_node->refcount)) + continue; + + orig_node = tmp_orig_node; + break; + } + rcu_read_unlock(); + + return orig_node; +} + /** * batadv_mcast_forw_mode - check on how to forward a multicast packet * @bat_priv: the bat priv with all the soft interface information @@ -344,10 +417,11 @@ enum batadv_forw_mode batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb, struct batadv_orig_node **orig) { + int ret, tt_count, unsnoop_count, total_count; + bool is_unsnoopable = false; struct ethhdr *ethhdr; - int ret, tt_count; - ret = batadv_mcast_forw_mode_check(bat_priv, skb); + ret = batadv_mcast_forw_mode_check(bat_priv, skb, &is_unsnoopable); if (ret == -ENOMEM) return BATADV_FORW_NONE; else if (ret < 0) @@ -357,10 +431,18 @@ batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb, tt_count = batadv_tt_global_hash_count(bat_priv, ethhdr->h_dest, BATADV_NO_FLAGS); + unsnoop_count = !is_unsnoopable ? 0 : + atomic_read(&bat_priv->mcast.num_want_all_unsnoopables); + + total_count = tt_count + unsnoop_count; - switch (tt_count) { + switch (total_count) { case 1: - *orig = batadv_mcast_forw_tt_node_get(bat_priv, ethhdr); + if (tt_count) + *orig = batadv_mcast_forw_tt_node_get(bat_priv, ethhdr); + else if (unsnoop_count) + *orig = batadv_mcast_forw_unsnoop_node_get(bat_priv); + if (*orig) return BATADV_FORW_SINGLE; @@ -372,6 +454,39 @@ batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb, } } +/** + * batadv_mcast_want_unsnoop_update - update unsnoop counter and list + * @bat_priv: the bat priv with all the soft interface information + * @orig: the orig_node which multicast state might have changed of + * @mcast_flags: flags indicating the new multicast state + * + * If the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag of this originator, + * orig, has toggled then this method updates counter and list accordingly. + */ +static void batadv_mcast_want_unsnoop_update(struct batadv_priv *bat_priv, + struct batadv_orig_node *orig, + uint8_t mcast_flags) +{ + /* switched from flag unset to set */ + if (mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES && + !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES)) { + atomic_inc(&bat_priv->mcast.num_want_all_unsnoopables); + + spin_lock_bh(&bat_priv->mcast.want_lists_lock); + hlist_add_head_rcu(&orig->mcast_want_all_unsnoopables_node, + &bat_priv->mcast.want_all_unsnoopables_list); + spin_unlock_bh(&bat_priv->mcast.want_lists_lock); + /* switched from flag set to unset */ + } else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) && + orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) { + atomic_dec(&bat_priv->mcast.num_want_all_unsnoopables); + + spin_lock_bh(&bat_priv->mcast.want_lists_lock); + hlist_del_rcu(&orig->mcast_want_all_unsnoopables_node); + spin_unlock_bh(&bat_priv->mcast.want_lists_lock); + } +} + /** * batadv_mcast_tvlv_ogm_handler_v1 - process incoming multicast tvlv container * @bat_priv: the bat priv with all the soft interface information @@ -416,6 +531,8 @@ static void batadv_mcast_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv, (tvlv_value_len >= sizeof(mcast_flags))) mcast_flags = *(uint8_t *)tvlv_value; + batadv_mcast_want_unsnoop_update(bat_priv, orig, mcast_flags); + orig->mcast_flags = mcast_flags; } @@ -452,4 +569,6 @@ void batadv_mcast_purge_orig(struct batadv_orig_node *orig) if (!(orig->capabilities & BATADV_ORIG_CAPA_HAS_MCAST)) atomic_dec(&bat_priv->mcast.num_disabled); + + batadv_mcast_want_unsnoop_update(bat_priv, orig, BATADV_NO_FLAGS); } -- cgit v1.2.3 From 4c8755d69cbde2ec464a39c932aed0a83f9ff89f Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Linus=20L=C3=BCssing?= Date: Sat, 15 Feb 2014 17:47:54 +0100 Subject: batman-adv: Send multicast packets to nodes with a WANT_ALL flag MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit With this patch a node sends IPv4 multicast packets to nodes which have a BATADV_MCAST_WANT_ALL_IPV4 flag set and IPv6 multicast packets to nodes which have a BATADV_MCAST_WANT_ALL_IPV6 flag set, too. Why is this needed? There are scenarios involving bridges where multicast report snooping and multicast TT announcements are not sufficient, which would lead to packet loss for some nodes otherwise: MLDv1 and IGMPv1/IGMPv2 have a suppression mechanism for multicast listener reports. When we have an MLDv1/IGMPv1/IGMPv2 querier behind a bridge then our snooping bridge is potentially not going to see any reports even though listeners exist because according to RFC4541 such reports are only forwarded to multicast routers: ----------------------------------------------------------- --------------- {Querier}---|Snoop. Switch|----{Listener} --------------- \ ^ ------- | br0 | < ??? ------- \ _-~---~_ _-~/ ~-_ ~ batman-adv \-----{Sender} \~_ cloud ~/ -~~__-__-~_/ I) MLDv1 Query: {Querier} -> flooded II) MLDv1 Report: {Listener} -> {Querier} -> br0 cannot detect the {Listener} => Packets from {Sender} need to be forwarded to all detected listeners and MLDv1/IGMPv1/IGMPv2 queriers. ----------------------------------------------------------- Note that we do not need to explicitly forward to MLDv2/IGMPv3 queriers, because these protocols have no report suppression: A bridge has no trouble detecting MLDv2/IGMPv3 listeners. Even though we do not support bridges yet we need to provide the according infrastructure already to not break compatibility later. Signed-off-by: Linus Lüssing Signed-off-by: Marek Lindner Signed-off-by: Antonio Quartulli --- net/batman-adv/multicast.c | 178 ++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 176 insertions(+), 2 deletions(-) (limited to 'net/batman-adv/multicast.c') diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c index a4804fa1ad11..8c7ca811de6e 100644 --- a/net/batman-adv/multicast.c +++ b/net/batman-adv/multicast.c @@ -360,6 +360,29 @@ static int batadv_mcast_forw_mode_check(struct batadv_priv *bat_priv, } } +/** + * batadv_mcast_want_all_ip_count - count nodes with unspecific mcast interest + * @bat_priv: the bat priv with all the soft interface information + * @ethhdr: ethernet header of a packet + * + * Returns the number of nodes which want all IPv4 multicast traffic if the + * given ethhdr is from an IPv4 packet or the number of nodes which want all + * IPv6 traffic if it matches an IPv6 packet. + */ +static int batadv_mcast_forw_want_all_ip_count(struct batadv_priv *bat_priv, + struct ethhdr *ethhdr) +{ + switch (ntohs(ethhdr->h_proto)) { + case ETH_P_IP: + return atomic_read(&bat_priv->mcast.num_want_all_ipv4); + case ETH_P_IPV6: + return atomic_read(&bat_priv->mcast.num_want_all_ipv6); + default: + /* we shouldn't be here... */ + return 0; + } +} + /** * batadv_mcast_forw_tt_node_get - get a multicast tt node * @bat_priv: the bat priv with all the soft interface information @@ -376,6 +399,84 @@ batadv_mcast_forw_tt_node_get(struct batadv_priv *bat_priv, ethhdr->h_dest, BATADV_NO_FLAGS); } +/** + * batadv_mcast_want_forw_ipv4_node_get - get a node with an ipv4 flag + * @bat_priv: the bat priv with all the soft interface information + * + * Returns an orig_node which has the BATADV_MCAST_WANT_ALL_IPV4 flag set and + * increases its refcount. + */ +static struct batadv_orig_node * +batadv_mcast_forw_ipv4_node_get(struct batadv_priv *bat_priv) +{ + struct batadv_orig_node *tmp_orig_node, *orig_node = NULL; + + rcu_read_lock(); + hlist_for_each_entry_rcu(tmp_orig_node, + &bat_priv->mcast.want_all_ipv4_list, + mcast_want_all_ipv4_node) { + if (!atomic_inc_not_zero(&orig_node->refcount)) + continue; + + orig_node = tmp_orig_node; + break; + } + rcu_read_unlock(); + + return orig_node; +} + +/** + * batadv_mcast_want_forw_ipv6_node_get - get a node with an ipv6 flag + * @bat_priv: the bat priv with all the soft interface information + * + * Returns an orig_node which has the BATADV_MCAST_WANT_ALL_IPV6 flag set + * and increases its refcount. + */ +static struct batadv_orig_node * +batadv_mcast_forw_ipv6_node_get(struct batadv_priv *bat_priv) +{ + struct batadv_orig_node *tmp_orig_node, *orig_node = NULL; + + rcu_read_lock(); + hlist_for_each_entry_rcu(tmp_orig_node, + &bat_priv->mcast.want_all_ipv6_list, + mcast_want_all_ipv6_node) { + if (!atomic_inc_not_zero(&orig_node->refcount)) + continue; + + orig_node = tmp_orig_node; + break; + } + rcu_read_unlock(); + + return orig_node; +} + +/** + * batadv_mcast_want_forw_ip_node_get - get a node with an ipv4/ipv6 flag + * @bat_priv: the bat priv with all the soft interface information + * @ethhdr: an ethernet header to determine the protocol family from + * + * Returns an orig_node which has the BATADV_MCAST_WANT_ALL_IPV4 or + * BATADV_MCAST_WANT_ALL_IPV6 flag, depending on the provided ethhdr, set and + * increases its refcount. + */ +static struct batadv_orig_node * +batadv_mcast_forw_ip_node_get(struct batadv_priv *bat_priv, + struct ethhdr *ethhdr) +{ + switch (ntohs(ethhdr->h_proto)) { + case ETH_P_IP: + return batadv_mcast_forw_ipv4_node_get(bat_priv); + case ETH_P_IPV6: + return batadv_mcast_forw_ipv6_node_get(bat_priv); + default: + /* we shouldn't be here... */ + return NULL; + } +} + /** * batadv_mcast_want_forw_unsnoop_node_get - get a node with an unsnoopable flag * @bat_priv: the bat priv with all the soft interface information @@ -417,7 +518,7 @@ enum batadv_forw_mode batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb, struct batadv_orig_node **orig) { - int ret, tt_count, unsnoop_count, total_count; + int ret, tt_count, ip_count, unsnoop_count, total_count; bool is_unsnoopable = false; struct ethhdr *ethhdr; @@ -431,15 +532,18 @@ batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb, tt_count = batadv_tt_global_hash_count(bat_priv, ethhdr->h_dest, BATADV_NO_FLAGS); + ip_count = batadv_mcast_forw_want_all_ip_count(bat_priv, ethhdr); unsnoop_count = !is_unsnoopable ? 0 : atomic_read(&bat_priv->mcast.num_want_all_unsnoopables); - total_count = tt_count + unsnoop_count; + total_count = tt_count + ip_count + unsnoop_count; switch (total_count) { case 1: if (tt_count) *orig = batadv_mcast_forw_tt_node_get(bat_priv, ethhdr); + else if (ip_count) + *orig = batadv_mcast_forw_ip_node_get(bat_priv, ethhdr); else if (unsnoop_count) *orig = batadv_mcast_forw_unsnoop_node_get(bat_priv); @@ -487,6 +591,72 @@ static void batadv_mcast_want_unsnoop_update(struct batadv_priv *bat_priv, } } +/** + * batadv_mcast_want_ipv4_update - update want-all-ipv4 counter and list + * @bat_priv: the bat priv with all the soft interface information + * @orig: the orig_node which multicast state might have changed of + * @mcast_flags: flags indicating the new multicast state + * + * If the BATADV_MCAST_WANT_ALL_IPV4 flag of this originator, orig, has + * toggled then this method updates counter and list accordingly. + */ +static void batadv_mcast_want_ipv4_update(struct batadv_priv *bat_priv, + struct batadv_orig_node *orig, + uint8_t mcast_flags) +{ + /* switched from flag unset to set */ + if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV4 && + !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4)) { + atomic_inc(&bat_priv->mcast.num_want_all_ipv4); + + spin_lock_bh(&bat_priv->mcast.want_lists_lock); + hlist_add_head_rcu(&orig->mcast_want_all_ipv4_node, + &bat_priv->mcast.want_all_ipv4_list); + spin_unlock_bh(&bat_priv->mcast.want_lists_lock); + /* switched from flag set to unset */ + } else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) && + orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) { + atomic_dec(&bat_priv->mcast.num_want_all_ipv4); + + spin_lock_bh(&bat_priv->mcast.want_lists_lock); + hlist_del_rcu(&orig->mcast_want_all_ipv4_node); + spin_unlock_bh(&bat_priv->mcast.want_lists_lock); + } +} + +/** + * batadv_mcast_want_ipv6_update - update want-all-ipv6 counter and list + * @bat_priv: the bat priv with all the soft interface information + * @orig: the orig_node which multicast state might have changed of + * @mcast_flags: flags indicating the new multicast state + * + * If the BATADV_MCAST_WANT_ALL_IPV6 flag of this originator, orig, has + * toggled then this method updates counter and list accordingly. + */ +static void batadv_mcast_want_ipv6_update(struct batadv_priv *bat_priv, + struct batadv_orig_node *orig, + uint8_t mcast_flags) +{ + /* switched from flag unset to set */ + if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV6 && + !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6)) { + atomic_inc(&bat_priv->mcast.num_want_all_ipv6); + + spin_lock_bh(&bat_priv->mcast.want_lists_lock); + hlist_add_head_rcu(&orig->mcast_want_all_ipv6_node, + &bat_priv->mcast.want_all_ipv6_list); + spin_unlock_bh(&bat_priv->mcast.want_lists_lock); + /* switched from flag set to unset */ + } else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) && + orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) { + atomic_dec(&bat_priv->mcast.num_want_all_ipv6); + + spin_lock_bh(&bat_priv->mcast.want_lists_lock); + hlist_del_rcu(&orig->mcast_want_all_ipv6_node); + spin_unlock_bh(&bat_priv->mcast.want_lists_lock); + } +} + /** * batadv_mcast_tvlv_ogm_handler_v1 - process incoming multicast tvlv container * @bat_priv: the bat priv with all the soft interface information @@ -532,6 +702,8 @@ static void batadv_mcast_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv, mcast_flags = *(uint8_t *)tvlv_value; batadv_mcast_want_unsnoop_update(bat_priv, orig, mcast_flags); + batadv_mcast_want_ipv4_update(bat_priv, orig, mcast_flags); + batadv_mcast_want_ipv6_update(bat_priv, orig, mcast_flags); orig->mcast_flags = mcast_flags; } @@ -571,4 +743,6 @@ void batadv_mcast_purge_orig(struct batadv_orig_node *orig) atomic_dec(&bat_priv->mcast.num_disabled); batadv_mcast_want_unsnoop_update(bat_priv, orig, BATADV_NO_FLAGS); + batadv_mcast_want_ipv4_update(bat_priv, orig, BATADV_NO_FLAGS); + batadv_mcast_want_ipv6_update(bat_priv, orig, BATADV_NO_FLAGS); } -- cgit v1.2.3