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Diffstat (limited to '')
| -rw-r--r-- | net/batman-adv/multicast.c | 2317 |
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); +} |