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-rw-r--r--net/batman-adv/multicast.c2317
1 files changed, 2317 insertions, 0 deletions
diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c
new file mode 100644
index 000000000..b23845591
--- /dev/null
+++ b/net/batman-adv/multicast.c
@@ -0,0 +1,2317 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) B.A.T.M.A.N. contributors:
+ *
+ * Linus Lüssing
+ */
+
+#include "multicast.h"
+#include "main.h"
+
+#include <linux/atomic.h>
+#include <linux/bitops.h>
+#include <linux/bug.h>
+#include <linux/byteorder/generic.h>
+#include <linux/container_of.h>
+#include <linux/errno.h>
+#include <linux/etherdevice.h>
+#include <linux/gfp.h>
+#include <linux/icmpv6.h>
+#include <linux/if_bridge.h>
+#include <linux/if_ether.h>
+#include <linux/igmp.h>
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/inetdevice.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/kref.h>
+#include <linux/list.h>
+#include <linux/lockdep.h>
+#include <linux/netdevice.h>
+#include <linux/netlink.h>
+#include <linux/printk.h>
+#include <linux/rculist.h>
+#include <linux/rcupdate.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/stddef.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/workqueue.h>
+#include <net/addrconf.h>
+#include <net/genetlink.h>
+#include <net/if_inet6.h>
+#include <net/ip.h>
+#include <net/ipv6.h>
+#include <net/netlink.h>
+#include <net/sock.h>
+#include <uapi/linux/batadv_packet.h>
+#include <uapi/linux/batman_adv.h>
+
+#include "bridge_loop_avoidance.h"
+#include "hard-interface.h"
+#include "hash.h"
+#include "log.h"
+#include "netlink.h"
+#include "send.h"
+#include "soft-interface.h"
+#include "translation-table.h"
+#include "tvlv.h"
+
+static void batadv_mcast_mla_update(struct work_struct *work);
+
+/**
+ * batadv_mcast_start_timer() - schedule the multicast periodic worker
+ * @bat_priv: the bat priv with all the soft interface information
+ */
+static void batadv_mcast_start_timer(struct batadv_priv *bat_priv)
+{
+ queue_delayed_work(batadv_event_workqueue, &bat_priv->mcast.work,
+ msecs_to_jiffies(BATADV_MCAST_WORK_PERIOD));
+}
+
+/**
+ * batadv_mcast_get_bridge() - get the bridge on top of the softif if it exists
+ * @soft_iface: netdev struct of the mesh interface
+ *
+ * If the given soft interface has a bridge on top then the refcount
+ * of the according net device is increased.
+ *
+ * Return: NULL if no such bridge exists. Otherwise the net device of the
+ * bridge.
+ */
+static struct net_device *batadv_mcast_get_bridge(struct net_device *soft_iface)
+{
+ struct net_device *upper = soft_iface;
+
+ rcu_read_lock();
+ do {
+ upper = netdev_master_upper_dev_get_rcu(upper);
+ } while (upper && !netif_is_bridge_master(upper));
+
+ dev_hold(upper);
+ rcu_read_unlock();
+
+ return upper;
+}
+
+/**
+ * batadv_mcast_mla_rtr_flags_softif_get_ipv4() - get mcast router flags from
+ * node for IPv4
+ * @dev: the interface to check
+ *
+ * Checks the presence of an IPv4 multicast router on this node.
+ *
+ * Caller needs to hold rcu read lock.
+ *
+ * Return: BATADV_NO_FLAGS if present, BATADV_MCAST_WANT_NO_RTR4 otherwise.
+ */
+static u8 batadv_mcast_mla_rtr_flags_softif_get_ipv4(struct net_device *dev)
+{
+ struct in_device *in_dev = __in_dev_get_rcu(dev);
+
+ if (in_dev && IN_DEV_MFORWARD(in_dev))
+ return BATADV_NO_FLAGS;
+ else
+ return BATADV_MCAST_WANT_NO_RTR4;
+}
+
+/**
+ * batadv_mcast_mla_rtr_flags_softif_get_ipv6() - get mcast router flags from
+ * node for IPv6
+ * @dev: the interface to check
+ *
+ * Checks the presence of an IPv6 multicast router on this node.
+ *
+ * Caller needs to hold rcu read lock.
+ *
+ * Return: BATADV_NO_FLAGS if present, BATADV_MCAST_WANT_NO_RTR6 otherwise.
+ */
+#if IS_ENABLED(CONFIG_IPV6_MROUTE)
+static u8 batadv_mcast_mla_rtr_flags_softif_get_ipv6(struct net_device *dev)
+{
+ struct inet6_dev *in6_dev = __in6_dev_get(dev);
+
+ if (in6_dev && atomic_read(&in6_dev->cnf.mc_forwarding))
+ return BATADV_NO_FLAGS;
+ else
+ return BATADV_MCAST_WANT_NO_RTR6;
+}
+#else
+static inline u8
+batadv_mcast_mla_rtr_flags_softif_get_ipv6(struct net_device *dev)
+{
+ return BATADV_MCAST_WANT_NO_RTR6;
+}
+#endif
+
+/**
+ * batadv_mcast_mla_rtr_flags_softif_get() - get mcast router flags from node
+ * @bat_priv: the bat priv with all the soft interface information
+ * @bridge: bridge interface on top of the soft_iface if present,
+ * otherwise pass NULL
+ *
+ * Checks the presence of IPv4 and IPv6 multicast routers on this
+ * node.
+ *
+ * Return:
+ * BATADV_NO_FLAGS: Both an IPv4 and IPv6 multicast router is present
+ * BATADV_MCAST_WANT_NO_RTR4: No IPv4 multicast router is present
+ * BATADV_MCAST_WANT_NO_RTR6: No IPv6 multicast router is present
+ * The former two OR'd: no multicast router is present
+ */
+static u8 batadv_mcast_mla_rtr_flags_softif_get(struct batadv_priv *bat_priv,
+ struct net_device *bridge)
+{
+ struct net_device *dev = bridge ? bridge : bat_priv->soft_iface;
+ u8 flags = BATADV_NO_FLAGS;
+
+ rcu_read_lock();
+
+ flags |= batadv_mcast_mla_rtr_flags_softif_get_ipv4(dev);
+ flags |= batadv_mcast_mla_rtr_flags_softif_get_ipv6(dev);
+
+ rcu_read_unlock();
+
+ return flags;
+}
+
+/**
+ * batadv_mcast_mla_rtr_flags_bridge_get() - get mcast router flags from bridge
+ * @bat_priv: the bat priv with all the soft interface information
+ * @bridge: bridge interface on top of the soft_iface if present,
+ * otherwise pass NULL
+ *
+ * Checks the presence of IPv4 and IPv6 multicast routers behind a bridge.
+ *
+ * Return:
+ * BATADV_NO_FLAGS: Both an IPv4 and IPv6 multicast router is present
+ * BATADV_MCAST_WANT_NO_RTR4: No IPv4 multicast router is present
+ * BATADV_MCAST_WANT_NO_RTR6: No IPv6 multicast router is present
+ * The former two OR'd: no multicast router is present
+ */
+static u8 batadv_mcast_mla_rtr_flags_bridge_get(struct batadv_priv *bat_priv,
+ struct net_device *bridge)
+{
+ struct net_device *dev = bat_priv->soft_iface;
+ u8 flags = BATADV_NO_FLAGS;
+
+ if (!bridge)
+ return BATADV_MCAST_WANT_NO_RTR4 | BATADV_MCAST_WANT_NO_RTR6;
+
+ if (!br_multicast_has_router_adjacent(dev, ETH_P_IP))
+ flags |= BATADV_MCAST_WANT_NO_RTR4;
+ if (!br_multicast_has_router_adjacent(dev, ETH_P_IPV6))
+ flags |= BATADV_MCAST_WANT_NO_RTR6;
+
+ return flags;
+}
+
+/**
+ * batadv_mcast_mla_rtr_flags_get() - get multicast router flags
+ * @bat_priv: the bat priv with all the soft interface information
+ * @bridge: bridge interface on top of the soft_iface if present,
+ * otherwise pass NULL
+ *
+ * Checks the presence of IPv4 and IPv6 multicast routers on this
+ * node or behind its bridge.
+ *
+ * Return:
+ * BATADV_NO_FLAGS: Both an IPv4 and IPv6 multicast router is present
+ * BATADV_MCAST_WANT_NO_RTR4: No IPv4 multicast router is present
+ * BATADV_MCAST_WANT_NO_RTR6: No IPv6 multicast router is present
+ * The former two OR'd: no multicast router is present
+ */
+static u8 batadv_mcast_mla_rtr_flags_get(struct batadv_priv *bat_priv,
+ struct net_device *bridge)
+{
+ u8 flags = BATADV_MCAST_WANT_NO_RTR4 | BATADV_MCAST_WANT_NO_RTR6;
+
+ flags &= batadv_mcast_mla_rtr_flags_softif_get(bat_priv, bridge);
+ flags &= batadv_mcast_mla_rtr_flags_bridge_get(bat_priv, bridge);
+
+ return flags;
+}
+
+/**
+ * batadv_mcast_mla_flags_get() - get the new multicast flags
+ * @bat_priv: the bat priv with all the soft interface information
+ *
+ * Return: A set of flags for the current/next TVLV, querier and
+ * bridge state.
+ */
+static struct batadv_mcast_mla_flags
+batadv_mcast_mla_flags_get(struct batadv_priv *bat_priv)
+{
+ struct net_device *dev = bat_priv->soft_iface;
+ struct batadv_mcast_querier_state *qr4, *qr6;
+ struct batadv_mcast_mla_flags mla_flags;
+ struct net_device *bridge;
+
+ bridge = batadv_mcast_get_bridge(dev);
+
+ memset(&mla_flags, 0, sizeof(mla_flags));
+ mla_flags.enabled = 1;
+ mla_flags.tvlv_flags |= batadv_mcast_mla_rtr_flags_get(bat_priv,
+ bridge);
+
+ if (!bridge)
+ return mla_flags;
+
+ dev_put(bridge);
+
+ mla_flags.bridged = 1;
+ qr4 = &mla_flags.querier_ipv4;
+ qr6 = &mla_flags.querier_ipv6;
+
+ if (!IS_ENABLED(CONFIG_BRIDGE_IGMP_SNOOPING))
+ pr_warn_once("No bridge IGMP snooping compiled - multicast optimizations disabled\n");
+
+ qr4->exists = br_multicast_has_querier_anywhere(dev, ETH_P_IP);
+ qr4->shadowing = br_multicast_has_querier_adjacent(dev, ETH_P_IP);
+
+ qr6->exists = br_multicast_has_querier_anywhere(dev, ETH_P_IPV6);
+ qr6->shadowing = br_multicast_has_querier_adjacent(dev, ETH_P_IPV6);
+
+ mla_flags.tvlv_flags |= BATADV_MCAST_WANT_ALL_UNSNOOPABLES;
+
+ /* 1) If no querier exists at all, then multicast listeners on
+ * our local TT clients behind the bridge will keep silent.
+ * 2) If the selected querier is on one of our local TT clients,
+ * behind the bridge, then this querier might shadow multicast
+ * listeners on our local TT clients, behind this bridge.
+ *
+ * In both cases, we will signalize other batman nodes that
+ * we need all multicast traffic of the according protocol.
+ */
+ if (!qr4->exists || qr4->shadowing) {
+ mla_flags.tvlv_flags |= BATADV_MCAST_WANT_ALL_IPV4;
+ mla_flags.tvlv_flags &= ~BATADV_MCAST_WANT_NO_RTR4;
+ }
+
+ if (!qr6->exists || qr6->shadowing) {
+ mla_flags.tvlv_flags |= BATADV_MCAST_WANT_ALL_IPV6;
+ mla_flags.tvlv_flags &= ~BATADV_MCAST_WANT_NO_RTR6;
+ }
+
+ return mla_flags;
+}
+
+/**
+ * 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
+ *
+ * Return: true if the given address is already in the given list.
+ * Otherwise returns false.
+ */
+static bool batadv_mcast_mla_is_duplicate(u8 *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_softif_get_ipv4() - get softif IPv4 multicast listeners
+ * @dev: the device to collect multicast addresses from
+ * @mcast_list: a list to put found addresses into
+ * @flags: flags indicating the new multicast state
+ *
+ * Collects multicast addresses of IPv4 multicast listeners residing
+ * on this kernel on the given soft interface, dev, in
+ * the given mcast_list. In general, multicast listeners provided by
+ * your multicast receiving applications run directly on this node.
+ *
+ * Return: -ENOMEM on memory allocation error or the number of
+ * items added to the mcast_list otherwise.
+ */
+static int
+batadv_mcast_mla_softif_get_ipv4(struct net_device *dev,
+ struct hlist_head *mcast_list,
+ struct batadv_mcast_mla_flags *flags)
+{
+ struct batadv_hw_addr *new;
+ struct in_device *in_dev;
+ u8 mcast_addr[ETH_ALEN];
+ struct ip_mc_list *pmc;
+ int ret = 0;
+
+ if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_IPV4)
+ return 0;
+
+ rcu_read_lock();
+
+ in_dev = __in_dev_get_rcu(dev);
+ if (!in_dev) {
+ rcu_read_unlock();
+ return 0;
+ }
+
+ for (pmc = rcu_dereference(in_dev->mc_list); pmc;
+ pmc = rcu_dereference(pmc->next_rcu)) {
+ if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
+ ipv4_is_local_multicast(pmc->multiaddr))
+ continue;
+
+ if (!(flags->tvlv_flags & BATADV_MCAST_WANT_NO_RTR4) &&
+ !ipv4_is_local_multicast(pmc->multiaddr))
+ continue;
+
+ ip_eth_mc_map(pmc->multiaddr, mcast_addr);
+
+ if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
+ continue;
+
+ new = kmalloc(sizeof(*new), GFP_ATOMIC);
+ if (!new) {
+ ret = -ENOMEM;
+ break;
+ }
+
+ ether_addr_copy(new->addr, mcast_addr);
+ hlist_add_head(&new->list, mcast_list);
+ ret++;
+ }
+ rcu_read_unlock();
+
+ return ret;
+}
+
+/**
+ * batadv_mcast_mla_softif_get_ipv6() - get softif IPv6 multicast listeners
+ * @dev: the device to collect multicast addresses from
+ * @mcast_list: a list to put found addresses into
+ * @flags: flags indicating the new multicast state
+ *
+ * Collects multicast addresses of IPv6 multicast listeners residing
+ * on this kernel on the given soft interface, dev, in
+ * the given mcast_list. In general, multicast listeners provided by
+ * your multicast receiving applications run directly on this node.
+ *
+ * Return: -ENOMEM on memory allocation error or the number of
+ * items added to the mcast_list otherwise.
+ */
+#if IS_ENABLED(CONFIG_IPV6)
+static int
+batadv_mcast_mla_softif_get_ipv6(struct net_device *dev,
+ struct hlist_head *mcast_list,
+ struct batadv_mcast_mla_flags *flags)
+{
+ struct batadv_hw_addr *new;
+ struct inet6_dev *in6_dev;
+ u8 mcast_addr[ETH_ALEN];
+ struct ifmcaddr6 *pmc6;
+ int ret = 0;
+
+ if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_IPV6)
+ return 0;
+
+ rcu_read_lock();
+
+ in6_dev = __in6_dev_get(dev);
+ if (!in6_dev) {
+ rcu_read_unlock();
+ return 0;
+ }
+
+ for (pmc6 = rcu_dereference(in6_dev->mc_list);
+ pmc6;
+ pmc6 = rcu_dereference(pmc6->next)) {
+ if (IPV6_ADDR_MC_SCOPE(&pmc6->mca_addr) <
+ IPV6_ADDR_SCOPE_LINKLOCAL)
+ continue;
+
+ if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
+ ipv6_addr_is_ll_all_nodes(&pmc6->mca_addr))
+ continue;
+
+ if (!(flags->tvlv_flags & BATADV_MCAST_WANT_NO_RTR6) &&
+ IPV6_ADDR_MC_SCOPE(&pmc6->mca_addr) >
+ IPV6_ADDR_SCOPE_LINKLOCAL)
+ continue;
+
+ ipv6_eth_mc_map(&pmc6->mca_addr, mcast_addr);
+
+ if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
+ continue;
+
+ new = kmalloc(sizeof(*new), GFP_ATOMIC);
+ if (!new) {
+ ret = -ENOMEM;
+ break;
+ }
+
+ ether_addr_copy(new->addr, mcast_addr);
+ hlist_add_head(&new->list, mcast_list);
+ ret++;
+ }
+ rcu_read_unlock();
+
+ return ret;
+}
+#else
+static inline int
+batadv_mcast_mla_softif_get_ipv6(struct net_device *dev,
+ struct hlist_head *mcast_list,
+ struct batadv_mcast_mla_flags *flags)
+{
+ return 0;
+}
+#endif
+
+/**
+ * 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
+ * @flags: flags indicating the new multicast state
+ *
+ * Collects multicast addresses of multicast listeners residing
+ * on this kernel on the given soft interface, dev, in
+ * the given mcast_list. In general, multicast listeners provided by
+ * your multicast receiving applications run directly on this node.
+ *
+ * If there is a bridge interface on top of dev, collect from that one
+ * instead. Just like with IP addresses and routes, multicast listeners
+ * will(/should) register to the bridge interface instead of an
+ * enslaved bat0.
+ *
+ * Return: -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 batadv_mcast_mla_flags *flags)
+{
+ struct net_device *bridge = batadv_mcast_get_bridge(dev);
+ int ret4, ret6 = 0;
+
+ if (bridge)
+ dev = bridge;
+
+ ret4 = batadv_mcast_mla_softif_get_ipv4(dev, mcast_list, flags);
+ if (ret4 < 0)
+ goto out;
+
+ ret6 = batadv_mcast_mla_softif_get_ipv6(dev, mcast_list, flags);
+ if (ret6 < 0) {
+ ret4 = 0;
+ goto out;
+ }
+
+out:
+ dev_put(bridge);
+
+ return ret4 + ret6;
+}
+
+/**
+ * batadv_mcast_mla_br_addr_cpy() - copy a bridge multicast address
+ * @dst: destination to write to - a multicast MAC address
+ * @src: source to read from - a multicast IP address
+ *
+ * Converts a given multicast IPv4/IPv6 address from a bridge
+ * to its matching multicast MAC address and copies it into the given
+ * destination buffer.
+ *
+ * Caller needs to make sure the destination buffer can hold
+ * at least ETH_ALEN bytes.
+ */
+static void batadv_mcast_mla_br_addr_cpy(char *dst, const struct br_ip *src)
+{
+ if (src->proto == htons(ETH_P_IP))
+ ip_eth_mc_map(src->dst.ip4, dst);
+#if IS_ENABLED(CONFIG_IPV6)
+ else if (src->proto == htons(ETH_P_IPV6))
+ ipv6_eth_mc_map(&src->dst.ip6, dst);
+#endif
+ else
+ eth_zero_addr(dst);
+}
+
+/**
+ * batadv_mcast_mla_bridge_get() - get bridged-in multicast listeners
+ * @dev: a bridge slave whose bridge to collect multicast addresses from
+ * @mcast_list: a list to put found addresses into
+ * @flags: flags indicating the new multicast state
+ *
+ * Collects multicast addresses of multicast listeners residing
+ * on foreign, non-mesh devices which we gave access to our mesh via
+ * a bridge on top of the given soft interface, dev, in the given
+ * mcast_list.
+ *
+ * Return: -ENOMEM on memory allocation error or the number of
+ * items added to the mcast_list otherwise.
+ */
+static int batadv_mcast_mla_bridge_get(struct net_device *dev,
+ struct hlist_head *mcast_list,
+ struct batadv_mcast_mla_flags *flags)
+{
+ struct list_head bridge_mcast_list = LIST_HEAD_INIT(bridge_mcast_list);
+ struct br_ip_list *br_ip_entry, *tmp;
+ u8 tvlv_flags = flags->tvlv_flags;
+ struct batadv_hw_addr *new;
+ u8 mcast_addr[ETH_ALEN];
+ int ret;
+
+ /* we don't need to detect these devices/listeners, the IGMP/MLD
+ * snooping code of the Linux bridge already does that for us
+ */
+ ret = br_multicast_list_adjacent(dev, &bridge_mcast_list);
+ if (ret < 0)
+ goto out;
+
+ list_for_each_entry(br_ip_entry, &bridge_mcast_list, list) {
+ if (br_ip_entry->addr.proto == htons(ETH_P_IP)) {
+ if (tvlv_flags & BATADV_MCAST_WANT_ALL_IPV4)
+ continue;
+
+ if (tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
+ ipv4_is_local_multicast(br_ip_entry->addr.dst.ip4))
+ continue;
+
+ if (!(tvlv_flags & BATADV_MCAST_WANT_NO_RTR4) &&
+ !ipv4_is_local_multicast(br_ip_entry->addr.dst.ip4))
+ continue;
+ }
+
+#if IS_ENABLED(CONFIG_IPV6)
+ if (br_ip_entry->addr.proto == htons(ETH_P_IPV6)) {
+ if (tvlv_flags & BATADV_MCAST_WANT_ALL_IPV6)
+ continue;
+
+ if (tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
+ ipv6_addr_is_ll_all_nodes(&br_ip_entry->addr.dst.ip6))
+ continue;
+
+ if (!(tvlv_flags & BATADV_MCAST_WANT_NO_RTR6) &&
+ IPV6_ADDR_MC_SCOPE(&br_ip_entry->addr.dst.ip6) >
+ IPV6_ADDR_SCOPE_LINKLOCAL)
+ continue;
+ }
+#endif
+
+ batadv_mcast_mla_br_addr_cpy(mcast_addr, &br_ip_entry->addr);
+ if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
+ continue;
+
+ new = kmalloc(sizeof(*new), GFP_ATOMIC);
+ if (!new) {
+ ret = -ENOMEM;
+ break;
+ }
+
+ ether_addr_copy(new->addr, mcast_addr);
+ hlist_add_head(&new->list, mcast_list);
+ }
+
+out:
+ list_for_each_entry_safe(br_ip_entry, tmp, &bridge_mcast_list, list) {
+ list_del(&br_ip_entry->list);
+ kfree(br_ip_entry);
+ }
+
+ return ret;
+}
+
+/**
+ * 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_querier_log() - debug output regarding the querier status on
+ * link
+ * @bat_priv: the bat priv with all the soft interface information
+ * @str_proto: a string for the querier protocol (e.g. "IGMP" or "MLD")
+ * @old_state: the previous querier state on our link
+ * @new_state: the new querier state on our link
+ *
+ * Outputs debug messages to the logging facility with log level 'mcast'
+ * regarding changes to the querier status on the link which are relevant
+ * to our multicast optimizations.
+ *
+ * Usually this is about whether a querier appeared or vanished in
+ * our mesh or whether the querier is in the suboptimal position of being
+ * behind our local bridge segment: Snooping switches will directly
+ * forward listener reports to the querier, therefore batman-adv and
+ * the bridge will potentially not see these listeners - the querier is
+ * potentially shadowing listeners from us then.
+ *
+ * This is only interesting for nodes with a bridge on top of their
+ * soft interface.
+ */
+static void
+batadv_mcast_querier_log(struct batadv_priv *bat_priv, char *str_proto,
+ struct batadv_mcast_querier_state *old_state,
+ struct batadv_mcast_querier_state *new_state)
+{
+ if (!old_state->exists && new_state->exists)
+ batadv_info(bat_priv->soft_iface, "%s Querier appeared\n",
+ str_proto);
+ else if (old_state->exists && !new_state->exists)
+ batadv_info(bat_priv->soft_iface,
+ "%s Querier disappeared - multicast optimizations disabled\n",
+ str_proto);
+ else if (!bat_priv->mcast.mla_flags.bridged && !new_state->exists)
+ batadv_info(bat_priv->soft_iface,
+ "No %s Querier present - multicast optimizations disabled\n",
+ str_proto);
+
+ if (new_state->exists) {
+ if ((!old_state->shadowing && new_state->shadowing) ||
+ (!old_state->exists && new_state->shadowing))
+ batadv_dbg(BATADV_DBG_MCAST, bat_priv,
+ "%s Querier is behind our bridged segment: Might shadow listeners\n",
+ str_proto);
+ else if (old_state->shadowing && !new_state->shadowing)
+ batadv_dbg(BATADV_DBG_MCAST, bat_priv,
+ "%s Querier is not behind our bridged segment\n",
+ str_proto);
+ }
+}
+
+/**
+ * batadv_mcast_bridge_log() - debug output for topology changes in bridged
+ * setups
+ * @bat_priv: the bat priv with all the soft interface information
+ * @new_flags: flags indicating the new multicast state
+ *
+ * If no bridges are ever used on this node, then this function does nothing.
+ *
+ * Otherwise this function outputs debug information to the 'mcast' log level
+ * which might be relevant to our multicast optimizations.
+ *
+ * More precisely, it outputs information when a bridge interface is added or
+ * removed from a soft interface. And when a bridge is present, it further
+ * outputs information about the querier state which is relevant for the
+ * multicast flags this node is going to set.
+ */
+static void
+batadv_mcast_bridge_log(struct batadv_priv *bat_priv,
+ struct batadv_mcast_mla_flags *new_flags)
+{
+ struct batadv_mcast_mla_flags *old_flags = &bat_priv->mcast.mla_flags;
+
+ if (!old_flags->bridged && new_flags->bridged)
+ batadv_dbg(BATADV_DBG_MCAST, bat_priv,
+ "Bridge added: Setting Unsnoopables(U)-flag\n");
+ else if (old_flags->bridged && !new_flags->bridged)
+ batadv_dbg(BATADV_DBG_MCAST, bat_priv,
+ "Bridge removed: Unsetting Unsnoopables(U)-flag\n");
+
+ if (new_flags->bridged) {
+ batadv_mcast_querier_log(bat_priv, "IGMP",
+ &old_flags->querier_ipv4,
+ &new_flags->querier_ipv4);
+ batadv_mcast_querier_log(bat_priv, "MLD",
+ &old_flags->querier_ipv6,
+ &new_flags->querier_ipv6);
+ }
+}
+
+/**
+ * batadv_mcast_flags_log() - output debug information about mcast flag changes
+ * @bat_priv: the bat priv with all the soft interface information
+ * @flags: TVLV flags indicating the new multicast state
+ *
+ * Whenever the multicast TVLV flags this node announces change, this function
+ * should be used to notify userspace about the change.
+ */
+static void batadv_mcast_flags_log(struct batadv_priv *bat_priv, u8 flags)
+{
+ bool old_enabled = bat_priv->mcast.mla_flags.enabled;
+ u8 old_flags = bat_priv->mcast.mla_flags.tvlv_flags;
+ char str_old_flags[] = "[.... . ]";
+
+ sprintf(str_old_flags, "[%c%c%c%s%s]",
+ (old_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) ? 'U' : '.',
+ (old_flags & BATADV_MCAST_WANT_ALL_IPV4) ? '4' : '.',
+ (old_flags & BATADV_MCAST_WANT_ALL_IPV6) ? '6' : '.',
+ !(old_flags & BATADV_MCAST_WANT_NO_RTR4) ? "R4" : ". ",
+ !(old_flags & BATADV_MCAST_WANT_NO_RTR6) ? "R6" : ". ");
+
+ batadv_dbg(BATADV_DBG_MCAST, bat_priv,
+ "Changing multicast flags from '%s' to '[%c%c%c%s%s]'\n",
+ old_enabled ? str_old_flags : "<undefined>",
+ (flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) ? 'U' : '.',
+ (flags & BATADV_MCAST_WANT_ALL_IPV4) ? '4' : '.',
+ (flags & BATADV_MCAST_WANT_ALL_IPV6) ? '6' : '.',
+ !(flags & BATADV_MCAST_WANT_NO_RTR4) ? "R4" : ". ",
+ !(flags & BATADV_MCAST_WANT_NO_RTR6) ? "R6" : ". ");
+}
+
+/**
+ * batadv_mcast_mla_flags_update() - update multicast flags
+ * @bat_priv: the bat priv with all the soft interface information
+ * @flags: flags indicating the new multicast state
+ *
+ * Updates the own multicast tvlv with our current multicast related settings,
+ * capabilities and inabilities.
+ */
+static void
+batadv_mcast_mla_flags_update(struct batadv_priv *bat_priv,
+ struct batadv_mcast_mla_flags *flags)
+{
+ struct batadv_tvlv_mcast_data mcast_data;
+
+ if (!memcmp(flags, &bat_priv->mcast.mla_flags, sizeof(*flags)))
+ return;
+
+ batadv_mcast_bridge_log(bat_priv, flags);
+ batadv_mcast_flags_log(bat_priv, flags->tvlv_flags);
+
+ mcast_data.flags = flags->tvlv_flags;
+ memset(mcast_data.reserved, 0, sizeof(mcast_data.reserved));
+
+ batadv_tvlv_container_register(bat_priv, BATADV_TVLV_MCAST, 2,
+ &mcast_data, sizeof(mcast_data));
+
+ bat_priv->mcast.mla_flags = *flags;
+}
+
+/**
+ * __batadv_mcast_mla_update() - update the own MLAs
+ * @bat_priv: the bat priv with all the soft interface information
+ *
+ * Updates the own multicast listener announcements in the translation
+ * table as well as the own, announced multicast tvlv container.
+ *
+ * Note that non-conflicting reads and writes to bat_priv->mcast.mla_list
+ * in batadv_mcast_mla_tt_retract() and batadv_mcast_mla_tt_add() are
+ * ensured by the non-parallel execution of the worker this function
+ * belongs to.
+ */
+static 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;
+ struct batadv_mcast_mla_flags flags;
+ int ret;
+
+ flags = batadv_mcast_mla_flags_get(bat_priv);
+
+ ret = batadv_mcast_mla_softif_get(soft_iface, &mcast_list, &flags);
+ if (ret < 0)
+ goto out;
+
+ ret = batadv_mcast_mla_bridge_get(soft_iface, &mcast_list, &flags);
+ if (ret < 0)
+ goto out;
+
+ spin_lock(&bat_priv->mcast.mla_lock);
+ batadv_mcast_mla_tt_retract(bat_priv, &mcast_list);
+ batadv_mcast_mla_tt_add(bat_priv, &mcast_list);
+ batadv_mcast_mla_flags_update(bat_priv, &flags);
+ spin_unlock(&bat_priv->mcast.mla_lock);
+
+out:
+ batadv_mcast_mla_list_free(&mcast_list);
+}
+
+/**
+ * batadv_mcast_mla_update() - update the own MLAs
+ * @work: kernel work struct
+ *
+ * Updates the own multicast listener announcements in the translation
+ * table as well as the own, announced multicast tvlv container.
+ *
+ * In the end, reschedules the work timer.
+ */
+static void batadv_mcast_mla_update(struct work_struct *work)
+{
+ struct delayed_work *delayed_work;
+ struct batadv_priv_mcast *priv_mcast;
+ struct batadv_priv *bat_priv;
+
+ delayed_work = to_delayed_work(work);
+ priv_mcast = container_of(delayed_work, struct batadv_priv_mcast, work);
+ bat_priv = container_of(priv_mcast, struct batadv_priv, mcast);
+
+ __batadv_mcast_mla_update(bat_priv);
+ batadv_mcast_start_timer(bat_priv);
+}
+
+/**
+ * batadv_mcast_is_report_ipv4() - check for IGMP reports
+ * @skb: the ethernet frame destined for the mesh
+ *
+ * This call might reallocate skb data.
+ *
+ * Checks whether the given frame is a valid IGMP report.
+ *
+ * Return: If so then true, otherwise false.
+ */
+static bool batadv_mcast_is_report_ipv4(struct sk_buff *skb)
+{
+ if (ip_mc_check_igmp(skb) < 0)
+ return false;
+
+ switch (igmp_hdr(skb)->type) {
+ case IGMP_HOST_MEMBERSHIP_REPORT:
+ case IGMPV2_HOST_MEMBERSHIP_REPORT:
+ case IGMPV3_HOST_MEMBERSHIP_REPORT:
+ return true;
+ }
+
+ return false;
+}
+
+/**
+ * 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
+ * @is_routable: stores whether the destination is routable
+ *
+ * Checks whether the given IPv4 packet has the potential to be forwarded with a
+ * mode more optimal than classic flooding.
+ *
+ * Return: If so then 0. Otherwise -EINVAL 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,
+ int *is_routable)
+{
+ 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;
+
+ if (batadv_mcast_is_report_ipv4(skb))
+ return -EINVAL;
+
+ iphdr = ip_hdr(skb);
+
+ /* link-local multicast listeners behind a bridge are
+ * not snoopable (see RFC4541, section 2.1.2.2)
+ */
+ if (ipv4_is_local_multicast(iphdr->daddr))
+ *is_unsnoopable = true;
+ else
+ *is_routable = ETH_P_IP;
+
+ return 0;
+}
+
+/**
+ * batadv_mcast_is_report_ipv6() - check for MLD reports
+ * @skb: the ethernet frame destined for the mesh
+ *
+ * This call might reallocate skb data.
+ *
+ * Checks whether the given frame is a valid MLD report.
+ *
+ * Return: If so then true, otherwise false.
+ */
+static bool batadv_mcast_is_report_ipv6(struct sk_buff *skb)
+{
+ if (ipv6_mc_check_mld(skb) < 0)
+ return false;
+
+ switch (icmp6_hdr(skb)->icmp6_type) {
+ case ICMPV6_MGM_REPORT:
+ case ICMPV6_MLD2_REPORT:
+ return true;
+ }
+
+ return false;
+}
+
+/**
+ * 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
+ * @is_routable: stores whether the destination is routable
+ *
+ * Checks whether the given IPv6 packet has the potential to be forwarded with a
+ * mode more optimal than classic flooding.
+ *
+ * Return: If so then 0. Otherwise -EINVAL is 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,
+ bool *is_unsnoopable,
+ int *is_routable)
+{
+ 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;
+
+ if (batadv_mcast_is_report_ipv6(skb))
+ return -EINVAL;
+
+ ip6hdr = ipv6_hdr(skb);
+
+ 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))
+ *is_unsnoopable = true;
+ else if (IPV6_ADDR_MC_SCOPE(&ip6hdr->daddr) > IPV6_ADDR_SCOPE_LINKLOCAL)
+ *is_routable = ETH_P_IPV6;
+
+ 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
+ * @is_unsnoopable: stores whether the destination is snoopable
+ * @is_routable: stores whether the destination is routable
+ *
+ * Checks whether the given multicast ethernet frame has the potential to be
+ * forwarded with a mode more optimal than classic flooding.
+ *
+ * Return: If so then 0. Otherwise -EINVAL is or -ENOMEM if we are out of memory
+ */
+static int batadv_mcast_forw_mode_check(struct batadv_priv *bat_priv,
+ struct sk_buff *skb,
+ bool *is_unsnoopable,
+ int *is_routable)
+{
+ struct ethhdr *ethhdr = eth_hdr(skb);
+
+ if (!atomic_read(&bat_priv->multicast_mode))
+ return -EINVAL;
+
+ switch (ntohs(ethhdr->h_proto)) {
+ case ETH_P_IP:
+ return batadv_mcast_forw_mode_check_ipv4(bat_priv, skb,
+ is_unsnoopable,
+ is_routable);
+ case ETH_P_IPV6:
+ if (!IS_ENABLED(CONFIG_IPV6))
+ return -EINVAL;
+
+ return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb,
+ is_unsnoopable,
+ is_routable);
+ default:
+ return -EINVAL;
+ }
+}
+
+/**
+ * batadv_mcast_forw_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
+ *
+ * Return: 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_rtr_count() - count nodes with a multicast router
+ * @bat_priv: the bat priv with all the soft interface information
+ * @protocol: the ethernet protocol type to count multicast routers for
+ *
+ * Return: the number of nodes which want all routable IPv4 multicast traffic
+ * if the protocol is ETH_P_IP or the number of nodes which want all routable
+ * IPv6 traffic if the protocol is ETH_P_IPV6. Otherwise returns 0.
+ */
+
+static int batadv_mcast_forw_rtr_count(struct batadv_priv *bat_priv,
+ int protocol)
+{
+ switch (protocol) {
+ case ETH_P_IP:
+ return atomic_read(&bat_priv->mcast.num_want_all_rtr4);
+ case ETH_P_IPV6:
+ return atomic_read(&bat_priv->mcast.num_want_all_rtr6);
+ default:
+ return 0;
+ }
+}
+
+/**
+ * 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
+ *
+ * Return: 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, NULL, ethhdr->h_dest,
+ BATADV_NO_FLAGS);
+}
+
+/**
+ * batadv_mcast_forw_ipv4_node_get() - get a node with an ipv4 flag
+ * @bat_priv: the bat priv with all the soft interface information
+ *
+ * Return: 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 (!kref_get_unless_zero(&tmp_orig_node->refcount))
+ continue;
+
+ orig_node = tmp_orig_node;
+ break;
+ }
+ rcu_read_unlock();
+
+ return orig_node;
+}
+
+/**
+ * batadv_mcast_forw_ipv6_node_get() - get a node with an ipv6 flag
+ * @bat_priv: the bat priv with all the soft interface information
+ *
+ * Return: 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 (!kref_get_unless_zero(&tmp_orig_node->refcount))
+ continue;
+
+ orig_node = tmp_orig_node;
+ break;
+ }
+ rcu_read_unlock();
+
+ return orig_node;
+}
+
+/**
+ * batadv_mcast_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
+ *
+ * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_IPV4 or
+ * BATADV_MCAST_WANT_ALL_IPV6 flag, depending on the provided ethhdr, sets 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_forw_unsnoop_node_get() - get a node with an unsnoopable flag
+ * @bat_priv: the bat priv with all the soft interface information
+ *
+ * Return: 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 (!kref_get_unless_zero(&tmp_orig_node->refcount))
+ continue;
+
+ orig_node = tmp_orig_node;
+ break;
+ }
+ rcu_read_unlock();
+
+ return orig_node;
+}
+
+/**
+ * batadv_mcast_forw_rtr4_node_get() - get a node with an ipv4 mcast router flag
+ * @bat_priv: the bat priv with all the soft interface information
+ *
+ * Return: an orig_node which has the BATADV_MCAST_WANT_NO_RTR4 flag unset and
+ * increases its refcount.
+ */
+static struct batadv_orig_node *
+batadv_mcast_forw_rtr4_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_rtr4_list,
+ mcast_want_all_rtr4_node) {
+ if (!kref_get_unless_zero(&tmp_orig_node->refcount))
+ continue;
+
+ orig_node = tmp_orig_node;
+ break;
+ }
+ rcu_read_unlock();
+
+ return orig_node;
+}
+
+/**
+ * batadv_mcast_forw_rtr6_node_get() - get a node with an ipv6 mcast router flag
+ * @bat_priv: the bat priv with all the soft interface information
+ *
+ * Return: an orig_node which has the BATADV_MCAST_WANT_NO_RTR6 flag unset
+ * and increases its refcount.
+ */
+static struct batadv_orig_node *
+batadv_mcast_forw_rtr6_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_rtr6_list,
+ mcast_want_all_rtr6_node) {
+ if (!kref_get_unless_zero(&tmp_orig_node->refcount))
+ continue;
+
+ orig_node = tmp_orig_node;
+ break;
+ }
+ rcu_read_unlock();
+
+ return orig_node;
+}
+
+/**
+ * batadv_mcast_forw_rtr_node_get() - get a node with an ipv4/ipv6 router flag
+ * @bat_priv: the bat priv with all the soft interface information
+ * @ethhdr: an ethernet header to determine the protocol family from
+ *
+ * Return: an orig_node which has no BATADV_MCAST_WANT_NO_RTR4 or
+ * BATADV_MCAST_WANT_NO_RTR6 flag, depending on the provided ethhdr, set and
+ * increases its refcount.
+ */
+static struct batadv_orig_node *
+batadv_mcast_forw_rtr_node_get(struct batadv_priv *bat_priv,
+ struct ethhdr *ethhdr)
+{
+ switch (ntohs(ethhdr->h_proto)) {
+ case ETH_P_IP:
+ return batadv_mcast_forw_rtr4_node_get(bat_priv);
+ case ETH_P_IPV6:
+ return batadv_mcast_forw_rtr6_node_get(bat_priv);
+ default:
+ /* we shouldn't be here... */
+ return NULL;
+ }
+}
+
+/**
+ * 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
+ * @is_routable: stores whether the destination is routable
+ *
+ * Return: 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, int *is_routable)
+{
+ int ret, tt_count, ip_count, unsnoop_count, total_count;
+ bool is_unsnoopable = false;
+ unsigned int mcast_fanout;
+ struct ethhdr *ethhdr;
+ int rtr_count = 0;
+
+ ret = batadv_mcast_forw_mode_check(bat_priv, skb, &is_unsnoopable,
+ is_routable);
+ 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);
+ 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);
+ rtr_count = batadv_mcast_forw_rtr_count(bat_priv, *is_routable);
+
+ total_count = tt_count + ip_count + unsnoop_count + rtr_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);
+ else if (rtr_count)
+ *orig = batadv_mcast_forw_rtr_node_get(bat_priv,
+ ethhdr);
+
+ if (*orig)
+ return BATADV_FORW_SINGLE;
+
+ fallthrough;
+ case 0:
+ return BATADV_FORW_NONE;
+ default:
+ mcast_fanout = atomic_read(&bat_priv->multicast_fanout);
+
+ if (!unsnoop_count && total_count <= mcast_fanout)
+ return BATADV_FORW_SOME;
+ }
+
+ return BATADV_FORW_ALL;
+}
+
+/**
+ * batadv_mcast_forw_send_orig() - send a multicast packet to an originator
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: the multicast packet to send
+ * @vid: the vlan identifier
+ * @orig_node: the originator to send the packet to
+ *
+ * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
+ */
+int batadv_mcast_forw_send_orig(struct batadv_priv *bat_priv,
+ struct sk_buff *skb,
+ unsigned short vid,
+ struct batadv_orig_node *orig_node)
+{
+ /* Avoid sending multicast-in-unicast packets to other BLA
+ * gateways - they already got the frame from the LAN side
+ * we share with them.
+ * TODO: Refactor to take BLA into account earlier, to avoid
+ * reducing the mcast_fanout count.
+ */
+ if (batadv_bla_is_backbone_gw_orig(bat_priv, orig_node->orig, vid)) {
+ dev_kfree_skb(skb);
+ return NET_XMIT_SUCCESS;
+ }
+
+ return batadv_send_skb_unicast(bat_priv, skb, BATADV_UNICAST, 0,
+ orig_node, vid);
+}
+
+/**
+ * batadv_mcast_forw_tt() - forwards a packet to multicast listeners
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: the multicast packet to transmit
+ * @vid: the vlan identifier
+ *
+ * Sends copies of a frame with multicast destination to any multicast
+ * listener registered in the translation table. A transmission is performed
+ * via a batman-adv unicast packet for each such destination node.
+ *
+ * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
+ * otherwise.
+ */
+static int
+batadv_mcast_forw_tt(struct batadv_priv *bat_priv, struct sk_buff *skb,
+ unsigned short vid)
+{
+ int ret = NET_XMIT_SUCCESS;
+ struct sk_buff *newskb;
+
+ struct batadv_tt_orig_list_entry *orig_entry;
+
+ struct batadv_tt_global_entry *tt_global;
+ const u8 *addr = eth_hdr(skb)->h_dest;
+
+ tt_global = batadv_tt_global_hash_find(bat_priv, addr, vid);
+ if (!tt_global)
+ goto out;
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(orig_entry, &tt_global->orig_list, list) {
+ newskb = skb_copy(skb, GFP_ATOMIC);
+ if (!newskb) {
+ ret = NET_XMIT_DROP;
+ break;
+ }
+
+ batadv_mcast_forw_send_orig(bat_priv, newskb, vid,
+ orig_entry->orig_node);
+ }
+ rcu_read_unlock();
+
+ batadv_tt_global_entry_put(tt_global);
+
+out:
+ return ret;
+}
+
+/**
+ * batadv_mcast_forw_want_all_ipv4() - forward to nodes with want-all-ipv4
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: the multicast packet to transmit
+ * @vid: the vlan identifier
+ *
+ * Sends copies of a frame with multicast destination to any node with a
+ * BATADV_MCAST_WANT_ALL_IPV4 flag set. A transmission is performed via a
+ * batman-adv unicast packet for each such destination node.
+ *
+ * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
+ * otherwise.
+ */
+static int
+batadv_mcast_forw_want_all_ipv4(struct batadv_priv *bat_priv,
+ struct sk_buff *skb, unsigned short vid)
+{
+ struct batadv_orig_node *orig_node;
+ int ret = NET_XMIT_SUCCESS;
+ struct sk_buff *newskb;
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(orig_node,
+ &bat_priv->mcast.want_all_ipv4_list,
+ mcast_want_all_ipv4_node) {
+ newskb = skb_copy(skb, GFP_ATOMIC);
+ if (!newskb) {
+ ret = NET_XMIT_DROP;
+ break;
+ }
+
+ batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
+ }
+ rcu_read_unlock();
+ return ret;
+}
+
+/**
+ * batadv_mcast_forw_want_all_ipv6() - forward to nodes with want-all-ipv6
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: The multicast packet to transmit
+ * @vid: the vlan identifier
+ *
+ * Sends copies of a frame with multicast destination to any node with a
+ * BATADV_MCAST_WANT_ALL_IPV6 flag set. A transmission is performed via a
+ * batman-adv unicast packet for each such destination node.
+ *
+ * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
+ * otherwise.
+ */
+static int
+batadv_mcast_forw_want_all_ipv6(struct batadv_priv *bat_priv,
+ struct sk_buff *skb, unsigned short vid)
+{
+ struct batadv_orig_node *orig_node;
+ int ret = NET_XMIT_SUCCESS;
+ struct sk_buff *newskb;
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(orig_node,
+ &bat_priv->mcast.want_all_ipv6_list,
+ mcast_want_all_ipv6_node) {
+ newskb = skb_copy(skb, GFP_ATOMIC);
+ if (!newskb) {
+ ret = NET_XMIT_DROP;
+ break;
+ }
+
+ batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
+ }
+ rcu_read_unlock();
+ return ret;
+}
+
+/**
+ * batadv_mcast_forw_want_all() - forward packet to nodes in a want-all list
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: the multicast packet to transmit
+ * @vid: the vlan identifier
+ *
+ * Sends copies of a frame with multicast destination to any node with a
+ * BATADV_MCAST_WANT_ALL_IPV4 or BATADV_MCAST_WANT_ALL_IPV6 flag set. A
+ * transmission is performed via a batman-adv unicast packet for each such
+ * destination node.
+ *
+ * Return: NET_XMIT_DROP on memory allocation failure or if the protocol family
+ * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise.
+ */
+static int
+batadv_mcast_forw_want_all(struct batadv_priv *bat_priv,
+ struct sk_buff *skb, unsigned short vid)
+{
+ switch (ntohs(eth_hdr(skb)->h_proto)) {
+ case ETH_P_IP:
+ return batadv_mcast_forw_want_all_ipv4(bat_priv, skb, vid);
+ case ETH_P_IPV6:
+ return batadv_mcast_forw_want_all_ipv6(bat_priv, skb, vid);
+ default:
+ /* we shouldn't be here... */
+ return NET_XMIT_DROP;
+ }
+}
+
+/**
+ * batadv_mcast_forw_want_all_rtr4() - forward to nodes with want-all-rtr4
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: the multicast packet to transmit
+ * @vid: the vlan identifier
+ *
+ * Sends copies of a frame with multicast destination to any node with a
+ * BATADV_MCAST_WANT_NO_RTR4 flag unset. A transmission is performed via a
+ * batman-adv unicast packet for each such destination node.
+ *
+ * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
+ * otherwise.
+ */
+static int
+batadv_mcast_forw_want_all_rtr4(struct batadv_priv *bat_priv,
+ struct sk_buff *skb, unsigned short vid)
+{
+ struct batadv_orig_node *orig_node;
+ int ret = NET_XMIT_SUCCESS;
+ struct sk_buff *newskb;
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(orig_node,
+ &bat_priv->mcast.want_all_rtr4_list,
+ mcast_want_all_rtr4_node) {
+ newskb = skb_copy(skb, GFP_ATOMIC);
+ if (!newskb) {
+ ret = NET_XMIT_DROP;
+ break;
+ }
+
+ batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
+ }
+ rcu_read_unlock();
+ return ret;
+}
+
+/**
+ * batadv_mcast_forw_want_all_rtr6() - forward to nodes with want-all-rtr6
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: The multicast packet to transmit
+ * @vid: the vlan identifier
+ *
+ * Sends copies of a frame with multicast destination to any node with a
+ * BATADV_MCAST_WANT_NO_RTR6 flag unset. A transmission is performed via a
+ * batman-adv unicast packet for each such destination node.
+ *
+ * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
+ * otherwise.
+ */
+static int
+batadv_mcast_forw_want_all_rtr6(struct batadv_priv *bat_priv,
+ struct sk_buff *skb, unsigned short vid)
+{
+ struct batadv_orig_node *orig_node;
+ int ret = NET_XMIT_SUCCESS;
+ struct sk_buff *newskb;
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(orig_node,
+ &bat_priv->mcast.want_all_rtr6_list,
+ mcast_want_all_rtr6_node) {
+ newskb = skb_copy(skb, GFP_ATOMIC);
+ if (!newskb) {
+ ret = NET_XMIT_DROP;
+ break;
+ }
+
+ batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
+ }
+ rcu_read_unlock();
+ return ret;
+}
+
+/**
+ * batadv_mcast_forw_want_rtr() - forward packet to nodes in a want-all-rtr list
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: the multicast packet to transmit
+ * @vid: the vlan identifier
+ *
+ * Sends copies of a frame with multicast destination to any node with a
+ * BATADV_MCAST_WANT_NO_RTR4 or BATADV_MCAST_WANT_NO_RTR6 flag unset. A
+ * transmission is performed via a batman-adv unicast packet for each such
+ * destination node.
+ *
+ * Return: NET_XMIT_DROP on memory allocation failure or if the protocol family
+ * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise.
+ */
+static int
+batadv_mcast_forw_want_rtr(struct batadv_priv *bat_priv,
+ struct sk_buff *skb, unsigned short vid)
+{
+ switch (ntohs(eth_hdr(skb)->h_proto)) {
+ case ETH_P_IP:
+ return batadv_mcast_forw_want_all_rtr4(bat_priv, skb, vid);
+ case ETH_P_IPV6:
+ return batadv_mcast_forw_want_all_rtr6(bat_priv, skb, vid);
+ default:
+ /* we shouldn't be here... */
+ return NET_XMIT_DROP;
+ }
+}
+
+/**
+ * batadv_mcast_forw_send() - send packet to any detected multicast recipient
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: the multicast packet to transmit
+ * @vid: the vlan identifier
+ * @is_routable: stores whether the destination is routable
+ *
+ * Sends copies of a frame with multicast destination to any node that signaled
+ * interest in it, that is either via the translation table or the according
+ * want-all flags. A transmission is performed via a batman-adv unicast packet
+ * for each such destination node.
+ *
+ * The given skb is consumed/freed.
+ *
+ * Return: NET_XMIT_DROP on memory allocation failure or if the protocol family
+ * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise.
+ */
+int batadv_mcast_forw_send(struct batadv_priv *bat_priv, struct sk_buff *skb,
+ unsigned short vid, int is_routable)
+{
+ int ret;
+
+ ret = batadv_mcast_forw_tt(bat_priv, skb, vid);
+ if (ret != NET_XMIT_SUCCESS) {
+ kfree_skb(skb);
+ return ret;
+ }
+
+ ret = batadv_mcast_forw_want_all(bat_priv, skb, vid);
+ if (ret != NET_XMIT_SUCCESS) {
+ kfree_skb(skb);
+ return ret;
+ }
+
+ if (!is_routable)
+ goto skip_mc_router;
+
+ ret = batadv_mcast_forw_want_rtr(bat_priv, skb, vid);
+ if (ret != NET_XMIT_SUCCESS) {
+ kfree_skb(skb);
+ return ret;
+ }
+
+skip_mc_router:
+ consume_skb(skb);
+ return ret;
+}
+
+/**
+ * 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 the counter and the list
+ * accordingly.
+ *
+ * Caller needs to hold orig->mcast_handler_lock.
+ */
+static void batadv_mcast_want_unsnoop_update(struct batadv_priv *bat_priv,
+ struct batadv_orig_node *orig,
+ u8 mcast_flags)
+{
+ struct hlist_node *node = &orig->mcast_want_all_unsnoopables_node;
+ struct hlist_head *head = &bat_priv->mcast.want_all_unsnoopables_list;
+
+ lockdep_assert_held(&orig->mcast_handler_lock);
+
+ /* 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);
+ /* flag checks above + mcast_handler_lock prevents this */
+ WARN_ON(!hlist_unhashed(node));
+
+ hlist_add_head_rcu(node, head);
+ 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);
+ /* flag checks above + mcast_handler_lock prevents this */
+ WARN_ON(hlist_unhashed(node));
+
+ hlist_del_init_rcu(node);
+ spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
+ }
+}
+
+/**
+ * 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 the counter and the list accordingly.
+ *
+ * Caller needs to hold orig->mcast_handler_lock.
+ */
+static void batadv_mcast_want_ipv4_update(struct batadv_priv *bat_priv,
+ struct batadv_orig_node *orig,
+ u8 mcast_flags)
+{
+ struct hlist_node *node = &orig->mcast_want_all_ipv4_node;
+ struct hlist_head *head = &bat_priv->mcast.want_all_ipv4_list;
+
+ lockdep_assert_held(&orig->mcast_handler_lock);
+
+ /* 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);
+ /* flag checks above + mcast_handler_lock prevents this */
+ WARN_ON(!hlist_unhashed(node));
+
+ hlist_add_head_rcu(node, head);
+ 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);
+ /* flag checks above + mcast_handler_lock prevents this */
+ WARN_ON(hlist_unhashed(node));
+
+ hlist_del_init_rcu(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 the counter and the list accordingly.
+ *
+ * Caller needs to hold orig->mcast_handler_lock.
+ */
+static void batadv_mcast_want_ipv6_update(struct batadv_priv *bat_priv,
+ struct batadv_orig_node *orig,
+ u8 mcast_flags)
+{
+ struct hlist_node *node = &orig->mcast_want_all_ipv6_node;
+ struct hlist_head *head = &bat_priv->mcast.want_all_ipv6_list;
+
+ lockdep_assert_held(&orig->mcast_handler_lock);
+
+ /* 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);
+ /* flag checks above + mcast_handler_lock prevents this */
+ WARN_ON(!hlist_unhashed(node));
+
+ hlist_add_head_rcu(node, head);
+ 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);
+ /* flag checks above + mcast_handler_lock prevents this */
+ WARN_ON(hlist_unhashed(node));
+
+ hlist_del_init_rcu(node);
+ spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
+ }
+}
+
+/**
+ * batadv_mcast_want_rtr4_update() - update want-all-rtr4 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_NO_RTR4 flag of this originator, orig, has
+ * toggled then this method updates the counter and the list accordingly.
+ *
+ * Caller needs to hold orig->mcast_handler_lock.
+ */
+static void batadv_mcast_want_rtr4_update(struct batadv_priv *bat_priv,
+ struct batadv_orig_node *orig,
+ u8 mcast_flags)
+{
+ struct hlist_node *node = &orig->mcast_want_all_rtr4_node;
+ struct hlist_head *head = &bat_priv->mcast.want_all_rtr4_list;
+
+ lockdep_assert_held(&orig->mcast_handler_lock);
+
+ /* switched from flag set to unset */
+ if (!(mcast_flags & BATADV_MCAST_WANT_NO_RTR4) &&
+ orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR4) {
+ atomic_inc(&bat_priv->mcast.num_want_all_rtr4);
+
+ spin_lock_bh(&bat_priv->mcast.want_lists_lock);
+ /* flag checks above + mcast_handler_lock prevents this */
+ WARN_ON(!hlist_unhashed(node));
+
+ hlist_add_head_rcu(node, head);
+ spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
+ /* switched from flag unset to set */
+ } else if (mcast_flags & BATADV_MCAST_WANT_NO_RTR4 &&
+ !(orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR4)) {
+ atomic_dec(&bat_priv->mcast.num_want_all_rtr4);
+
+ spin_lock_bh(&bat_priv->mcast.want_lists_lock);
+ /* flag checks above + mcast_handler_lock prevents this */
+ WARN_ON(hlist_unhashed(node));
+
+ hlist_del_init_rcu(node);
+ spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
+ }
+}
+
+/**
+ * batadv_mcast_want_rtr6_update() - update want-all-rtr6 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_NO_RTR6 flag of this originator, orig, has
+ * toggled then this method updates the counter and the list accordingly.
+ *
+ * Caller needs to hold orig->mcast_handler_lock.
+ */
+static void batadv_mcast_want_rtr6_update(struct batadv_priv *bat_priv,
+ struct batadv_orig_node *orig,
+ u8 mcast_flags)
+{
+ struct hlist_node *node = &orig->mcast_want_all_rtr6_node;
+ struct hlist_head *head = &bat_priv->mcast.want_all_rtr6_list;
+
+ lockdep_assert_held(&orig->mcast_handler_lock);
+
+ /* switched from flag set to unset */
+ if (!(mcast_flags & BATADV_MCAST_WANT_NO_RTR6) &&
+ orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR6) {
+ atomic_inc(&bat_priv->mcast.num_want_all_rtr6);
+
+ spin_lock_bh(&bat_priv->mcast.want_lists_lock);
+ /* flag checks above + mcast_handler_lock prevents this */
+ WARN_ON(!hlist_unhashed(node));
+
+ hlist_add_head_rcu(node, head);
+ spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
+ /* switched from flag unset to set */
+ } else if (mcast_flags & BATADV_MCAST_WANT_NO_RTR6 &&
+ !(orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR6)) {
+ atomic_dec(&bat_priv->mcast.num_want_all_rtr6);
+
+ spin_lock_bh(&bat_priv->mcast.want_lists_lock);
+ /* flag checks above + mcast_handler_lock prevents this */
+ WARN_ON(hlist_unhashed(node));
+
+ hlist_del_init_rcu(node);
+ spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
+ }
+}
+
+/**
+ * batadv_mcast_tvlv_flags_get() - get multicast flags from an OGM TVLV
+ * @enabled: whether the originator has multicast TVLV support enabled
+ * @tvlv_value: tvlv buffer containing the multicast flags
+ * @tvlv_value_len: tvlv buffer length
+ *
+ * Return: multicast flags for the given tvlv buffer
+ */
+static u8
+batadv_mcast_tvlv_flags_get(bool enabled, void *tvlv_value, u16 tvlv_value_len)
+{
+ u8 mcast_flags = BATADV_NO_FLAGS;
+
+ if (enabled && tvlv_value && tvlv_value_len >= sizeof(mcast_flags))
+ mcast_flags = *(u8 *)tvlv_value;
+
+ if (!enabled) {
+ mcast_flags |= BATADV_MCAST_WANT_ALL_IPV4;
+ mcast_flags |= BATADV_MCAST_WANT_ALL_IPV6;
+ }
+
+ /* remove redundant flags to avoid sending duplicate packets later */
+ if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV4)
+ mcast_flags |= BATADV_MCAST_WANT_NO_RTR4;
+
+ if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV6)
+ mcast_flags |= BATADV_MCAST_WANT_NO_RTR6;
+
+ return mcast_flags;
+}
+
+/**
+ * batadv_mcast_tvlv_ogm_handler() - 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(struct batadv_priv *bat_priv,
+ struct batadv_orig_node *orig,
+ u8 flags,
+ void *tvlv_value,
+ u16 tvlv_value_len)
+{
+ bool orig_mcast_enabled = !(flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
+ u8 mcast_flags;
+
+ mcast_flags = batadv_mcast_tvlv_flags_get(orig_mcast_enabled,
+ tvlv_value, tvlv_value_len);
+
+ spin_lock_bh(&orig->mcast_handler_lock);
+
+ if (orig_mcast_enabled &&
+ !test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities)) {
+ set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities);
+ } else if (!orig_mcast_enabled &&
+ test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities)) {
+ clear_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities);
+ }
+
+ set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capa_initialized);
+
+ 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);
+ batadv_mcast_want_rtr4_update(bat_priv, orig, mcast_flags);
+ batadv_mcast_want_rtr6_update(bat_priv, orig, mcast_flags);
+
+ orig->mcast_flags = mcast_flags;
+ spin_unlock_bh(&orig->mcast_handler_lock);
+}
+
+/**
+ * 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,
+ NULL, BATADV_TVLV_MCAST, 2,
+ BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
+
+ INIT_DELAYED_WORK(&bat_priv->mcast.work, batadv_mcast_mla_update);
+ batadv_mcast_start_timer(bat_priv);
+}
+
+/**
+ * batadv_mcast_mesh_info_put() - put multicast info into a netlink message
+ * @msg: buffer for the message
+ * @bat_priv: the bat priv with all the soft interface information
+ *
+ * Return: 0 or error code.
+ */
+int batadv_mcast_mesh_info_put(struct sk_buff *msg,
+ struct batadv_priv *bat_priv)
+{
+ u32 flags = bat_priv->mcast.mla_flags.tvlv_flags;
+ u32 flags_priv = BATADV_NO_FLAGS;
+
+ if (bat_priv->mcast.mla_flags.bridged) {
+ flags_priv |= BATADV_MCAST_FLAGS_BRIDGED;
+
+ if (bat_priv->mcast.mla_flags.querier_ipv4.exists)
+ flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV4_EXISTS;
+ if (bat_priv->mcast.mla_flags.querier_ipv6.exists)
+ flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV6_EXISTS;
+ if (bat_priv->mcast.mla_flags.querier_ipv4.shadowing)
+ flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV4_SHADOWING;
+ if (bat_priv->mcast.mla_flags.querier_ipv6.shadowing)
+ flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV6_SHADOWING;
+ }
+
+ if (nla_put_u32(msg, BATADV_ATTR_MCAST_FLAGS, flags) ||
+ nla_put_u32(msg, BATADV_ATTR_MCAST_FLAGS_PRIV, flags_priv))
+ return -EMSGSIZE;
+
+ return 0;
+}
+
+/**
+ * batadv_mcast_flags_dump_entry() - dump one entry of the multicast flags table
+ * to a netlink socket
+ * @msg: buffer for the message
+ * @portid: netlink port
+ * @cb: Control block containing additional options
+ * @orig_node: originator to dump the multicast flags of
+ *
+ * Return: 0 or error code.
+ */
+static int
+batadv_mcast_flags_dump_entry(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
+ struct batadv_orig_node *orig_node)
+{
+ void *hdr;
+
+ hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
+ &batadv_netlink_family, NLM_F_MULTI,
+ BATADV_CMD_GET_MCAST_FLAGS);
+ if (!hdr)
+ return -ENOBUFS;
+
+ genl_dump_check_consistent(cb, hdr);
+
+ if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
+ orig_node->orig)) {
+ genlmsg_cancel(msg, hdr);
+ return -EMSGSIZE;
+ }
+
+ if (test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
+ &orig_node->capabilities)) {
+ if (nla_put_u32(msg, BATADV_ATTR_MCAST_FLAGS,
+ orig_node->mcast_flags)) {
+ genlmsg_cancel(msg, hdr);
+ return -EMSGSIZE;
+ }
+ }
+
+ genlmsg_end(msg, hdr);
+ return 0;
+}
+
+/**
+ * batadv_mcast_flags_dump_bucket() - dump one bucket of the multicast flags
+ * table to a netlink socket
+ * @msg: buffer for the message
+ * @portid: netlink port
+ * @cb: Control block containing additional options
+ * @hash: hash to dump
+ * @bucket: bucket index to dump
+ * @idx_skip: How many entries to skip
+ *
+ * Return: 0 or error code.
+ */
+static int
+batadv_mcast_flags_dump_bucket(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
+ struct batadv_hashtable *hash,
+ unsigned int bucket, long *idx_skip)
+{
+ struct batadv_orig_node *orig_node;
+ long idx = 0;
+
+ spin_lock_bh(&hash->list_locks[bucket]);
+ cb->seq = atomic_read(&hash->generation) << 1 | 1;
+
+ hlist_for_each_entry(orig_node, &hash->table[bucket], hash_entry) {
+ if (!test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
+ &orig_node->capa_initialized))
+ continue;
+
+ if (idx < *idx_skip)
+ goto skip;
+
+ if (batadv_mcast_flags_dump_entry(msg, portid, cb, orig_node)) {
+ spin_unlock_bh(&hash->list_locks[bucket]);
+ *idx_skip = idx;
+
+ return -EMSGSIZE;
+ }
+
+skip:
+ idx++;
+ }
+ spin_unlock_bh(&hash->list_locks[bucket]);
+
+ return 0;
+}
+
+/**
+ * __batadv_mcast_flags_dump() - dump multicast flags table to a netlink socket
+ * @msg: buffer for the message
+ * @portid: netlink port
+ * @cb: Control block containing additional options
+ * @bat_priv: the bat priv with all the soft interface information
+ * @bucket: current bucket to dump
+ * @idx: index in current bucket to the next entry to dump
+ *
+ * Return: 0 or error code.
+ */
+static int
+__batadv_mcast_flags_dump(struct sk_buff *msg, u32 portid,
+ struct netlink_callback *cb,
+ struct batadv_priv *bat_priv, long *bucket, long *idx)
+{
+ struct batadv_hashtable *hash = bat_priv->orig_hash;
+ long bucket_tmp = *bucket;
+ long idx_tmp = *idx;
+
+ while (bucket_tmp < hash->size) {
+ if (batadv_mcast_flags_dump_bucket(msg, portid, cb, hash,
+ bucket_tmp, &idx_tmp))
+ break;
+
+ bucket_tmp++;
+ idx_tmp = 0;
+ }
+
+ *bucket = bucket_tmp;
+ *idx = idx_tmp;
+
+ return msg->len;
+}
+
+/**
+ * batadv_mcast_netlink_get_primary() - get primary interface from netlink
+ * callback
+ * @cb: netlink callback structure
+ * @primary_if: the primary interface pointer to return the result in
+ *
+ * Return: 0 or error code.
+ */
+static int
+batadv_mcast_netlink_get_primary(struct netlink_callback *cb,
+ struct batadv_hard_iface **primary_if)
+{
+ struct batadv_hard_iface *hard_iface = NULL;
+ struct net *net = sock_net(cb->skb->sk);
+ struct net_device *soft_iface;
+ struct batadv_priv *bat_priv;
+ int ifindex;
+ int ret = 0;
+
+ ifindex = batadv_netlink_get_ifindex(cb->nlh, BATADV_ATTR_MESH_IFINDEX);
+ if (!ifindex)
+ return -EINVAL;
+
+ soft_iface = dev_get_by_index(net, ifindex);
+ if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ bat_priv = netdev_priv(soft_iface);
+
+ hard_iface = batadv_primary_if_get_selected(bat_priv);
+ if (!hard_iface || hard_iface->if_status != BATADV_IF_ACTIVE) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+out:
+ dev_put(soft_iface);
+
+ if (!ret && primary_if)
+ *primary_if = hard_iface;
+ else
+ batadv_hardif_put(hard_iface);
+
+ return ret;
+}
+
+/**
+ * batadv_mcast_flags_dump() - dump multicast flags table to a netlink socket
+ * @msg: buffer for the message
+ * @cb: callback structure containing arguments
+ *
+ * Return: message length.
+ */
+int batadv_mcast_flags_dump(struct sk_buff *msg, struct netlink_callback *cb)
+{
+ struct batadv_hard_iface *primary_if = NULL;
+ int portid = NETLINK_CB(cb->skb).portid;
+ struct batadv_priv *bat_priv;
+ long *bucket = &cb->args[0];
+ long *idx = &cb->args[1];
+ int ret;
+
+ ret = batadv_mcast_netlink_get_primary(cb, &primary_if);
+ if (ret)
+ return ret;
+
+ bat_priv = netdev_priv(primary_if->soft_iface);
+ ret = __batadv_mcast_flags_dump(msg, portid, cb, bat_priv, bucket, idx);
+
+ batadv_hardif_put(primary_if);
+ return ret;
+}
+
+/**
+ * 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)
+{
+ cancel_delayed_work_sync(&bat_priv->mcast.work);
+
+ batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_MCAST, 2);
+ batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_MCAST, 2);
+
+ /* safely calling outside of worker, as worker was canceled above */
+ 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;
+
+ spin_lock_bh(&orig->mcast_handler_lock);
+
+ 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);
+ batadv_mcast_want_rtr4_update(bat_priv, orig,
+ BATADV_MCAST_WANT_NO_RTR4);
+ batadv_mcast_want_rtr6_update(bat_priv, orig,
+ BATADV_MCAST_WANT_NO_RTR6);
+
+ spin_unlock_bh(&orig->mcast_handler_lock);
+}