root/net/batman-adv/multicast.c

DEFINITIONS

1. batadv_mcast_start_timer
2. batadv_mcast_get_bridge
3. batadv_mcast_mla_rtr_flags_softif_get_ipv4
4. batadv_mcast_mla_rtr_flags_softif_get_ipv6
5. batadv_mcast_mla_rtr_flags_softif_get_ipv6
6. batadv_mcast_mla_rtr_flags_softif_get
7. batadv_mcast_mla_rtr_flags_bridge_get
8. batadv_mcast_mla_rtr_flags_bridge_get
9. batadv_mcast_mla_rtr_flags_get
10. batadv_mcast_mla_flags_get
11. batadv_mcast_mla_is_duplicate
12. batadv_mcast_mla_softif_get_ipv4
13. batadv_mcast_mla_softif_get_ipv6
14. batadv_mcast_mla_softif_get_ipv6
15. batadv_mcast_mla_softif_get
16. batadv_mcast_mla_br_addr_cpy
17. batadv_mcast_mla_bridge_get
18. batadv_mcast_mla_list_free
19. batadv_mcast_mla_tt_retract
20. batadv_mcast_mla_tt_add
21. batadv_mcast_querier_log
22. batadv_mcast_bridge_log
23. batadv_mcast_flags_log
24. batadv_mcast_mla_flags_update
25. __batadv_mcast_mla_update
26. batadv_mcast_mla_update
27. batadv_mcast_is_report_ipv4
28. batadv_mcast_forw_mode_check_ipv4
29. batadv_mcast_is_report_ipv6
30. batadv_mcast_forw_mode_check_ipv6
31. batadv_mcast_forw_mode_check
32. batadv_mcast_forw_want_all_ip_count
33. batadv_mcast_forw_rtr_count
34. batadv_mcast_forw_tt_node_get
35. batadv_mcast_forw_ipv4_node_get
36. batadv_mcast_forw_ipv6_node_get
37. batadv_mcast_forw_ip_node_get
38. batadv_mcast_forw_unsnoop_node_get
39. batadv_mcast_forw_rtr4_node_get
40. batadv_mcast_forw_rtr6_node_get
41. batadv_mcast_forw_rtr_node_get
42. batadv_mcast_forw_mode
43. batadv_mcast_forw_tt
44. batadv_mcast_forw_want_all_ipv4
45. batadv_mcast_forw_want_all_ipv6
46. batadv_mcast_forw_want_all
47. batadv_mcast_forw_want_all_rtr4
48. batadv_mcast_forw_want_all_rtr6
49. batadv_mcast_forw_want_rtr
50. batadv_mcast_forw_send
51. batadv_mcast_want_unsnoop_update
52. batadv_mcast_want_ipv4_update
53. batadv_mcast_want_ipv6_update
54. batadv_mcast_want_rtr4_update
55. batadv_mcast_want_rtr6_update
56. batadv_mcast_tvlv_flags_get
57. batadv_mcast_tvlv_ogm_handler
58. batadv_mcast_init
59. batadv_mcast_flags_print_header
60. batadv_mcast_flags_seq_print_text
61. batadv_mcast_mesh_info_put
62. batadv_mcast_flags_dump_entry
63. batadv_mcast_flags_dump_bucket
64. __batadv_mcast_flags_dump
65. batadv_mcast_netlink_get_primary
66. batadv_mcast_flags_dump
67. batadv_mcast_free
68. batadv_mcast_purge_orig

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (C) 2014-2019  B.A.T.M.A.N. contributors:
   3  *
   4  * Linus Lüssing
   5  */
   6 
   7 #include "multicast.h"
   8 #include "main.h"
   9 
  10 #include <linux/atomic.h>
  11 #include <linux/bitops.h>
  12 #include <linux/bug.h>
  13 #include <linux/byteorder/generic.h>
  14 #include <linux/errno.h>
  15 #include <linux/etherdevice.h>
  16 #include <linux/gfp.h>
  17 #include <linux/icmpv6.h>
  18 #include <linux/if_bridge.h>
  19 #include <linux/if_ether.h>
  20 #include <linux/igmp.h>
  21 #include <linux/in.h>
  22 #include <linux/in6.h>
  23 #include <linux/inetdevice.h>
  24 #include <linux/ip.h>
  25 #include <linux/ipv6.h>
  26 #include <linux/jiffies.h>
  27 #include <linux/kernel.h>
  28 #include <linux/kref.h>
  29 #include <linux/list.h>
  30 #include <linux/lockdep.h>
  31 #include <linux/netdevice.h>
  32 #include <linux/netlink.h>
  33 #include <linux/printk.h>
  34 #include <linux/rculist.h>
  35 #include <linux/rcupdate.h>
  36 #include <linux/seq_file.h>
  37 #include <linux/skbuff.h>
  38 #include <linux/slab.h>
  39 #include <linux/spinlock.h>
  40 #include <linux/stddef.h>
  41 #include <linux/string.h>
  42 #include <linux/types.h>
  43 #include <linux/workqueue.h>
  44 #include <net/addrconf.h>
  45 #include <net/genetlink.h>
  46 #include <net/if_inet6.h>
  47 #include <net/ip.h>
  48 #include <net/ipv6.h>
  49 #include <net/netlink.h>
  50 #include <net/sock.h>
  51 #include <uapi/linux/batadv_packet.h>
  52 #include <uapi/linux/batman_adv.h>
  53 
  54 #include "hard-interface.h"
  55 #include "hash.h"
  56 #include "log.h"
  57 #include "netlink.h"
  58 #include "send.h"
  59 #include "soft-interface.h"
  60 #include "translation-table.h"
  61 #include "tvlv.h"
  62 
  63 static void batadv_mcast_mla_update(struct work_struct *work);
  64 
  65 /**
  66  * batadv_mcast_start_timer() - schedule the multicast periodic worker
  67  * @bat_priv: the bat priv with all the soft interface information
  68  */
  69 static void batadv_mcast_start_timer(struct batadv_priv *bat_priv)
  70 {
  71         queue_delayed_work(batadv_event_workqueue, &bat_priv->mcast.work,
  72                            msecs_to_jiffies(BATADV_MCAST_WORK_PERIOD));
  73 }
  74 
  75 /**
  76  * batadv_mcast_get_bridge() - get the bridge on top of the softif if it exists
  77  * @soft_iface: netdev struct of the mesh interface
  78  *
  79  * If the given soft interface has a bridge on top then the refcount
  80  * of the according net device is increased.
  81  *
  82  * Return: NULL if no such bridge exists. Otherwise the net device of the
  83  * bridge.
  84  */
  85 static struct net_device *batadv_mcast_get_bridge(struct net_device *soft_iface)
  86 {
  87         struct net_device *upper = soft_iface;
  88 
  89         rcu_read_lock();
  90         do {
  91                 upper = netdev_master_upper_dev_get_rcu(upper);
  92         } while (upper && !(upper->priv_flags & IFF_EBRIDGE));
  93 
  94         if (upper)
  95                 dev_hold(upper);
  96         rcu_read_unlock();
  97 
  98         return upper;
  99 }
 100 
 101 /**
 102  * batadv_mcast_mla_rtr_flags_softif_get_ipv4() - get mcast router flags from
 103  *  node for IPv4
 104  * @dev: the interface to check
 105  *
 106  * Checks the presence of an IPv4 multicast router on this node.
 107  *
 108  * Caller needs to hold rcu read lock.
 109  *
 110  * Return: BATADV_NO_FLAGS if present, BATADV_MCAST_WANT_NO_RTR4 otherwise.
 111  */
 112 static u8 batadv_mcast_mla_rtr_flags_softif_get_ipv4(struct net_device *dev)
 113 {
 114         struct in_device *in_dev = __in_dev_get_rcu(dev);
 115 
 116         if (in_dev && IN_DEV_MFORWARD(in_dev))
 117                 return BATADV_NO_FLAGS;
 118         else
 119                 return BATADV_MCAST_WANT_NO_RTR4;
 120 }
 121 
 122 /**
 123  * batadv_mcast_mla_rtr_flags_softif_get_ipv6() - get mcast router flags from
 124  *  node for IPv6
 125  * @dev: the interface to check
 126  *
 127  * Checks the presence of an IPv6 multicast router on this node.
 128  *
 129  * Caller needs to hold rcu read lock.
 130  *
 131  * Return: BATADV_NO_FLAGS if present, BATADV_MCAST_WANT_NO_RTR6 otherwise.
 132  */
 133 #if IS_ENABLED(CONFIG_IPV6_MROUTE)
 134 static u8 batadv_mcast_mla_rtr_flags_softif_get_ipv6(struct net_device *dev)
 135 {
 136         struct inet6_dev *in6_dev = __in6_dev_get(dev);
 137 
 138         if (in6_dev && in6_dev->cnf.mc_forwarding)
 139                 return BATADV_NO_FLAGS;
 140         else
 141                 return BATADV_MCAST_WANT_NO_RTR6;
 142 }
 143 #else
 144 static inline u8
 145 batadv_mcast_mla_rtr_flags_softif_get_ipv6(struct net_device *dev)
 146 {
 147         return BATADV_MCAST_WANT_NO_RTR6;
 148 }
 149 #endif
 150 
 151 /**
 152  * batadv_mcast_mla_rtr_flags_softif_get() - get mcast router flags from node
 153  * @bat_priv: the bat priv with all the soft interface information
 154  * @bridge: bridge interface on top of the soft_iface if present,
 155  *  otherwise pass NULL
 156  *
 157  * Checks the presence of IPv4 and IPv6 multicast routers on this
 158  * node.
 159  *
 160  * Return:
 161  *      BATADV_NO_FLAGS: Both an IPv4 and IPv6 multicast router is present
 162  *      BATADV_MCAST_WANT_NO_RTR4: No IPv4 multicast router is present
 163  *      BATADV_MCAST_WANT_NO_RTR6: No IPv6 multicast router is present
 164  *      The former two OR'd: no multicast router is present
 165  */
 166 static u8 batadv_mcast_mla_rtr_flags_softif_get(struct batadv_priv *bat_priv,
 167                                                 struct net_device *bridge)
 168 {
 169         struct net_device *dev = bridge ? bridge : bat_priv->soft_iface;
 170         u8 flags = BATADV_NO_FLAGS;
 171 
 172         rcu_read_lock();
 173 
 174         flags |= batadv_mcast_mla_rtr_flags_softif_get_ipv4(dev);
 175         flags |= batadv_mcast_mla_rtr_flags_softif_get_ipv6(dev);
 176 
 177         rcu_read_unlock();
 178 
 179         return flags;
 180 }
 181 
 182 /**
 183  * batadv_mcast_mla_rtr_flags_bridge_get() - get mcast router flags from bridge
 184  * @bat_priv: the bat priv with all the soft interface information
 185  * @bridge: bridge interface on top of the soft_iface if present,
 186  *  otherwise pass NULL
 187  *
 188  * Checks the presence of IPv4 and IPv6 multicast routers behind a bridge.
 189  *
 190  * Return:
 191  *      BATADV_NO_FLAGS: Both an IPv4 and IPv6 multicast router is present
 192  *      BATADV_MCAST_WANT_NO_RTR4: No IPv4 multicast router is present
 193  *      BATADV_MCAST_WANT_NO_RTR6: No IPv6 multicast router is present
 194  *      The former two OR'd: no multicast router is present
 195  */
 196 #if IS_ENABLED(CONFIG_IPV6)
 197 static u8 batadv_mcast_mla_rtr_flags_bridge_get(struct batadv_priv *bat_priv,
 198                                                 struct net_device *bridge)
 199 {
 200         struct list_head bridge_mcast_list = LIST_HEAD_INIT(bridge_mcast_list);
 201         struct net_device *dev = bat_priv->soft_iface;
 202         struct br_ip_list *br_ip_entry, *tmp;
 203         u8 flags = BATADV_MCAST_WANT_NO_RTR6;
 204         int ret;
 205 
 206         if (!bridge)
 207                 return BATADV_MCAST_WANT_NO_RTR4 | BATADV_MCAST_WANT_NO_RTR6;
 208 
 209         /* TODO: ask the bridge if a multicast router is present (the bridge
 210          * is capable of performing proper RFC4286 multicast multicast router
 211          * discovery) instead of searching for a ff02::2 listener here
 212          */
 213         ret = br_multicast_list_adjacent(dev, &bridge_mcast_list);
 214         if (ret < 0)
 215                 return BATADV_NO_FLAGS;
 216 
 217         list_for_each_entry_safe(br_ip_entry, tmp, &bridge_mcast_list, list) {
 218                 /* the bridge snooping does not maintain IPv4 link-local
 219                  * addresses - therefore we won't find any IPv4 multicast router
 220                  * address here, only IPv6 ones
 221                  */
 222                 if (br_ip_entry->addr.proto == htons(ETH_P_IPV6) &&
 223                     ipv6_addr_is_ll_all_routers(&br_ip_entry->addr.u.ip6))
 224                         flags &= ~BATADV_MCAST_WANT_NO_RTR6;
 225 
 226                 list_del(&br_ip_entry->list);
 227                 kfree(br_ip_entry);
 228         }
 229 
 230         return flags;
 231 }
 232 #else
 233 static inline u8
 234 batadv_mcast_mla_rtr_flags_bridge_get(struct batadv_priv *bat_priv,
 235                                       struct net_device *bridge)
 236 {
 237         if (bridge)
 238                 return BATADV_NO_FLAGS;
 239         else
 240                 return BATADV_MCAST_WANT_NO_RTR4 | BATADV_MCAST_WANT_NO_RTR6;
 241 }
 242 #endif
 243 
 244 /**
 245  * batadv_mcast_mla_rtr_flags_get() - get multicast router flags
 246  * @bat_priv: the bat priv with all the soft interface information
 247  * @bridge: bridge interface on top of the soft_iface if present,
 248  *  otherwise pass NULL
 249  *
 250  * Checks the presence of IPv4 and IPv6 multicast routers on this
 251  * node or behind its bridge.
 252  *
 253  * Return:
 254  *      BATADV_NO_FLAGS: Both an IPv4 and IPv6 multicast router is present
 255  *      BATADV_MCAST_WANT_NO_RTR4: No IPv4 multicast router is present
 256  *      BATADV_MCAST_WANT_NO_RTR6: No IPv6 multicast router is present
 257  *      The former two OR'd: no multicast router is present
 258  */
 259 static u8 batadv_mcast_mla_rtr_flags_get(struct batadv_priv *bat_priv,
 260                                          struct net_device *bridge)
 261 {
 262         u8 flags = BATADV_MCAST_WANT_NO_RTR4 | BATADV_MCAST_WANT_NO_RTR6;
 263 
 264         flags &= batadv_mcast_mla_rtr_flags_softif_get(bat_priv, bridge);
 265         flags &= batadv_mcast_mla_rtr_flags_bridge_get(bat_priv, bridge);
 266 
 267         return flags;
 268 }
 269 
 270 /**
 271  * batadv_mcast_mla_flags_get() - get the new multicast flags
 272  * @bat_priv: the bat priv with all the soft interface information
 273  *
 274  * Return: A set of flags for the current/next TVLV, querier and
 275  * bridge state.
 276  */
 277 static struct batadv_mcast_mla_flags
 278 batadv_mcast_mla_flags_get(struct batadv_priv *bat_priv)
 279 {
 280         struct net_device *dev = bat_priv->soft_iface;
 281         struct batadv_mcast_querier_state *qr4, *qr6;
 282         struct batadv_mcast_mla_flags mla_flags;
 283         struct net_device *bridge;
 284 
 285         bridge = batadv_mcast_get_bridge(dev);
 286 
 287         memset(&mla_flags, 0, sizeof(mla_flags));
 288         mla_flags.enabled = 1;
 289         mla_flags.tvlv_flags |= batadv_mcast_mla_rtr_flags_get(bat_priv,
 290                                                                bridge);
 291 
 292         if (!bridge)
 293                 return mla_flags;
 294 
 295         dev_put(bridge);
 296 
 297         mla_flags.bridged = 1;
 298         qr4 = &mla_flags.querier_ipv4;
 299         qr6 = &mla_flags.querier_ipv6;
 300 
 301         if (!IS_ENABLED(CONFIG_BRIDGE_IGMP_SNOOPING))
 302                 pr_warn_once("No bridge IGMP snooping compiled - multicast optimizations disabled\n");
 303 
 304         qr4->exists = br_multicast_has_querier_anywhere(dev, ETH_P_IP);
 305         qr4->shadowing = br_multicast_has_querier_adjacent(dev, ETH_P_IP);
 306 
 307         qr6->exists = br_multicast_has_querier_anywhere(dev, ETH_P_IPV6);
 308         qr6->shadowing = br_multicast_has_querier_adjacent(dev, ETH_P_IPV6);
 309 
 310         mla_flags.tvlv_flags |= BATADV_MCAST_WANT_ALL_UNSNOOPABLES;
 311 
 312         /* 1) If no querier exists at all, then multicast listeners on
 313          *    our local TT clients behind the bridge will keep silent.
 314          * 2) If the selected querier is on one of our local TT clients,
 315          *    behind the bridge, then this querier might shadow multicast
 316          *    listeners on our local TT clients, behind this bridge.
 317          *
 318          * In both cases, we will signalize other batman nodes that
 319          * we need all multicast traffic of the according protocol.
 320          */
 321         if (!qr4->exists || qr4->shadowing) {
 322                 mla_flags.tvlv_flags |= BATADV_MCAST_WANT_ALL_IPV4;
 323                 mla_flags.tvlv_flags &= ~BATADV_MCAST_WANT_NO_RTR4;
 324         }
 325 
 326         if (!qr6->exists || qr6->shadowing) {
 327                 mla_flags.tvlv_flags |= BATADV_MCAST_WANT_ALL_IPV6;
 328                 mla_flags.tvlv_flags &= ~BATADV_MCAST_WANT_NO_RTR6;
 329         }
 330 
 331         return mla_flags;
 332 }
 333 
 334 /**
 335  * batadv_mcast_mla_is_duplicate() - check whether an address is in a list
 336  * @mcast_addr: the multicast address to check
 337  * @mcast_list: the list with multicast addresses to search in
 338  *
 339  * Return: true if the given address is already in the given list.
 340  * Otherwise returns false.
 341  */
 342 static bool batadv_mcast_mla_is_duplicate(u8 *mcast_addr,
 343                                           struct hlist_head *mcast_list)
 344 {
 345         struct batadv_hw_addr *mcast_entry;
 346 
 347         hlist_for_each_entry(mcast_entry, mcast_list, list)
 348                 if (batadv_compare_eth(mcast_entry->addr, mcast_addr))
 349                         return true;
 350 
 351         return false;
 352 }
 353 
 354 /**
 355  * batadv_mcast_mla_softif_get_ipv4() - get softif IPv4 multicast listeners
 356  * @dev: the device to collect multicast addresses from
 357  * @mcast_list: a list to put found addresses into
 358  * @flags: flags indicating the new multicast state
 359  *
 360  * Collects multicast addresses of IPv4 multicast listeners residing
 361  * on this kernel on the given soft interface, dev, in
 362  * the given mcast_list. In general, multicast listeners provided by
 363  * your multicast receiving applications run directly on this node.
 364  *
 365  * Return: -ENOMEM on memory allocation error or the number of
 366  * items added to the mcast_list otherwise.
 367  */
 368 static int
 369 batadv_mcast_mla_softif_get_ipv4(struct net_device *dev,
 370                                  struct hlist_head *mcast_list,
 371                                  struct batadv_mcast_mla_flags *flags)
 372 {
 373         struct batadv_hw_addr *new;
 374         struct in_device *in_dev;
 375         u8 mcast_addr[ETH_ALEN];
 376         struct ip_mc_list *pmc;
 377         int ret = 0;
 378 
 379         if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_IPV4)
 380                 return 0;
 381 
 382         rcu_read_lock();
 383 
 384         in_dev = __in_dev_get_rcu(dev);
 385         if (!in_dev) {
 386                 rcu_read_unlock();
 387                 return 0;
 388         }
 389 
 390         for (pmc = rcu_dereference(in_dev->mc_list); pmc;
 391              pmc = rcu_dereference(pmc->next_rcu)) {
 392                 if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
 393                     ipv4_is_local_multicast(pmc->multiaddr))
 394                         continue;
 395 
 396                 if (!(flags->tvlv_flags & BATADV_MCAST_WANT_NO_RTR4) &&
 397                     !ipv4_is_local_multicast(pmc->multiaddr))
 398                         continue;
 399 
 400                 ip_eth_mc_map(pmc->multiaddr, mcast_addr);
 401 
 402                 if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
 403                         continue;
 404 
 405                 new = kmalloc(sizeof(*new), GFP_ATOMIC);
 406                 if (!new) {
 407                         ret = -ENOMEM;
 408                         break;
 409                 }
 410 
 411                 ether_addr_copy(new->addr, mcast_addr);
 412                 hlist_add_head(&new->list, mcast_list);
 413                 ret++;
 414         }
 415         rcu_read_unlock();
 416 
 417         return ret;
 418 }
 419 
 420 /**
 421  * batadv_mcast_mla_softif_get_ipv6() - get softif IPv6 multicast listeners
 422  * @dev: the device to collect multicast addresses from
 423  * @mcast_list: a list to put found addresses into
 424  * @flags: flags indicating the new multicast state
 425  *
 426  * Collects multicast addresses of IPv6 multicast listeners residing
 427  * on this kernel on the given soft interface, dev, in
 428  * the given mcast_list. In general, multicast listeners provided by
 429  * your multicast receiving applications run directly on this node.
 430  *
 431  * Return: -ENOMEM on memory allocation error or the number of
 432  * items added to the mcast_list otherwise.
 433  */
 434 #if IS_ENABLED(CONFIG_IPV6)
 435 static int
 436 batadv_mcast_mla_softif_get_ipv6(struct net_device *dev,
 437                                  struct hlist_head *mcast_list,
 438                                  struct batadv_mcast_mla_flags *flags)
 439 {
 440         struct batadv_hw_addr *new;
 441         struct inet6_dev *in6_dev;
 442         u8 mcast_addr[ETH_ALEN];
 443         struct ifmcaddr6 *pmc6;
 444         int ret = 0;
 445 
 446         if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_IPV6)
 447                 return 0;
 448 
 449         rcu_read_lock();
 450 
 451         in6_dev = __in6_dev_get(dev);
 452         if (!in6_dev) {
 453                 rcu_read_unlock();
 454                 return 0;
 455         }
 456 
 457         read_lock_bh(&in6_dev->lock);
 458         for (pmc6 = in6_dev->mc_list; pmc6; pmc6 = pmc6->next) {
 459                 if (IPV6_ADDR_MC_SCOPE(&pmc6->mca_addr) <
 460                     IPV6_ADDR_SCOPE_LINKLOCAL)
 461                         continue;
 462 
 463                 if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
 464                     ipv6_addr_is_ll_all_nodes(&pmc6->mca_addr))
 465                         continue;
 466 
 467                 if (!(flags->tvlv_flags & BATADV_MCAST_WANT_NO_RTR6) &&
 468                     IPV6_ADDR_MC_SCOPE(&pmc6->mca_addr) >
 469                     IPV6_ADDR_SCOPE_LINKLOCAL)
 470                         continue;
 471 
 472                 ipv6_eth_mc_map(&pmc6->mca_addr, mcast_addr);
 473 
 474                 if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
 475                         continue;
 476 
 477                 new = kmalloc(sizeof(*new), GFP_ATOMIC);
 478                 if (!new) {
 479                         ret = -ENOMEM;
 480                         break;
 481                 }
 482 
 483                 ether_addr_copy(new->addr, mcast_addr);
 484                 hlist_add_head(&new->list, mcast_list);
 485                 ret++;
 486         }
 487         read_unlock_bh(&in6_dev->lock);
 488         rcu_read_unlock();
 489 
 490         return ret;
 491 }
 492 #else
 493 static inline int
 494 batadv_mcast_mla_softif_get_ipv6(struct net_device *dev,
 495                                  struct hlist_head *mcast_list,
 496                                  struct batadv_mcast_mla_flags *flags)
 497 {
 498         return 0;
 499 }
 500 #endif
 501 
 502 /**
 503  * batadv_mcast_mla_softif_get() - get softif multicast listeners
 504  * @dev: the device to collect multicast addresses from
 505  * @mcast_list: a list to put found addresses into
 506  * @flags: flags indicating the new multicast state
 507  *
 508  * Collects multicast addresses of multicast listeners residing
 509  * on this kernel on the given soft interface, dev, in
 510  * the given mcast_list. In general, multicast listeners provided by
 511  * your multicast receiving applications run directly on this node.
 512  *
 513  * If there is a bridge interface on top of dev, collects from that one
 514  * instead. Just like with IP addresses and routes, multicast listeners
 515  * will(/should) register to the bridge interface instead of an
 516  * enslaved bat0.
 517  *
 518  * Return: -ENOMEM on memory allocation error or the number of
 519  * items added to the mcast_list otherwise.
 520  */
 521 static int
 522 batadv_mcast_mla_softif_get(struct net_device *dev,
 523                             struct hlist_head *mcast_list,
 524                             struct batadv_mcast_mla_flags *flags)
 525 {
 526         struct net_device *bridge = batadv_mcast_get_bridge(dev);
 527         int ret4, ret6 = 0;
 528 
 529         if (bridge)
 530                 dev = bridge;
 531 
 532         ret4 = batadv_mcast_mla_softif_get_ipv4(dev, mcast_list, flags);
 533         if (ret4 < 0)
 534                 goto out;
 535 
 536         ret6 = batadv_mcast_mla_softif_get_ipv6(dev, mcast_list, flags);
 537         if (ret6 < 0) {
 538                 ret4 = 0;
 539                 goto out;
 540         }
 541 
 542 out:
 543         if (bridge)
 544                 dev_put(bridge);
 545 
 546         return ret4 + ret6;
 547 }
 548 
 549 /**
 550  * batadv_mcast_mla_br_addr_cpy() - copy a bridge multicast address
 551  * @dst: destination to write to - a multicast MAC address
 552  * @src: source to read from - a multicast IP address
 553  *
 554  * Converts a given multicast IPv4/IPv6 address from a bridge
 555  * to its matching multicast MAC address and copies it into the given
 556  * destination buffer.
 557  *
 558  * Caller needs to make sure the destination buffer can hold
 559  * at least ETH_ALEN bytes.
 560  */
 561 static void batadv_mcast_mla_br_addr_cpy(char *dst, const struct br_ip *src)
 562 {
 563         if (src->proto == htons(ETH_P_IP))
 564                 ip_eth_mc_map(src->u.ip4, dst);
 565 #if IS_ENABLED(CONFIG_IPV6)
 566         else if (src->proto == htons(ETH_P_IPV6))
 567                 ipv6_eth_mc_map(&src->u.ip6, dst);
 568 #endif
 569         else
 570                 eth_zero_addr(dst);
 571 }
 572 
 573 /**
 574  * batadv_mcast_mla_bridge_get() - get bridged-in multicast listeners
 575  * @dev: a bridge slave whose bridge to collect multicast addresses from
 576  * @mcast_list: a list to put found addresses into
 577  * @flags: flags indicating the new multicast state
 578  *
 579  * Collects multicast addresses of multicast listeners residing
 580  * on foreign, non-mesh devices which we gave access to our mesh via
 581  * a bridge on top of the given soft interface, dev, in the given
 582  * mcast_list.
 583  *
 584  * Return: -ENOMEM on memory allocation error or the number of
 585  * items added to the mcast_list otherwise.
 586  */
 587 static int batadv_mcast_mla_bridge_get(struct net_device *dev,
 588                                        struct hlist_head *mcast_list,
 589                                        struct batadv_mcast_mla_flags *flags)
 590 {
 591         struct list_head bridge_mcast_list = LIST_HEAD_INIT(bridge_mcast_list);
 592         struct br_ip_list *br_ip_entry, *tmp;
 593         u8 tvlv_flags = flags->tvlv_flags;
 594         struct batadv_hw_addr *new;
 595         u8 mcast_addr[ETH_ALEN];
 596         int ret;
 597 
 598         /* we don't need to detect these devices/listeners, the IGMP/MLD
 599          * snooping code of the Linux bridge already does that for us
 600          */
 601         ret = br_multicast_list_adjacent(dev, &bridge_mcast_list);
 602         if (ret < 0)
 603                 goto out;
 604 
 605         list_for_each_entry(br_ip_entry, &bridge_mcast_list, list) {
 606                 if (br_ip_entry->addr.proto == htons(ETH_P_IP)) {
 607                         if (tvlv_flags & BATADV_MCAST_WANT_ALL_IPV4)
 608                                 continue;
 609 
 610                         if (tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
 611                             ipv4_is_local_multicast(br_ip_entry->addr.u.ip4))
 612                                 continue;
 613 
 614                         if (!(tvlv_flags & BATADV_MCAST_WANT_NO_RTR4) &&
 615                             !ipv4_is_local_multicast(br_ip_entry->addr.u.ip4))
 616                                 continue;
 617                 }
 618 
 619 #if IS_ENABLED(CONFIG_IPV6)
 620                 if (br_ip_entry->addr.proto == htons(ETH_P_IPV6)) {
 621                         if (tvlv_flags & BATADV_MCAST_WANT_ALL_IPV6)
 622                                 continue;
 623 
 624                         if (tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
 625                             ipv6_addr_is_ll_all_nodes(&br_ip_entry->addr.u.ip6))
 626                                 continue;
 627 
 628                         if (!(tvlv_flags & BATADV_MCAST_WANT_NO_RTR6) &&
 629                             IPV6_ADDR_MC_SCOPE(&br_ip_entry->addr.u.ip6) >
 630                             IPV6_ADDR_SCOPE_LINKLOCAL)
 631                                 continue;
 632                 }
 633 #endif
 634 
 635                 batadv_mcast_mla_br_addr_cpy(mcast_addr, &br_ip_entry->addr);
 636                 if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
 637                         continue;
 638 
 639                 new = kmalloc(sizeof(*new), GFP_ATOMIC);
 640                 if (!new) {
 641                         ret = -ENOMEM;
 642                         break;
 643                 }
 644 
 645                 ether_addr_copy(new->addr, mcast_addr);
 646                 hlist_add_head(&new->list, mcast_list);
 647         }
 648 
 649 out:
 650         list_for_each_entry_safe(br_ip_entry, tmp, &bridge_mcast_list, list) {
 651                 list_del(&br_ip_entry->list);
 652                 kfree(br_ip_entry);
 653         }
 654 
 655         return ret;
 656 }
 657 
 658 /**
 659  * batadv_mcast_mla_list_free() - free a list of multicast addresses
 660  * @mcast_list: the list to free
 661  *
 662  * Removes and frees all items in the given mcast_list.
 663  */
 664 static void batadv_mcast_mla_list_free(struct hlist_head *mcast_list)
 665 {
 666         struct batadv_hw_addr *mcast_entry;
 667         struct hlist_node *tmp;
 668 
 669         hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) {
 670                 hlist_del(&mcast_entry->list);
 671                 kfree(mcast_entry);
 672         }
 673 }
 674 
 675 /**
 676  * batadv_mcast_mla_tt_retract() - clean up multicast listener announcements
 677  * @bat_priv: the bat priv with all the soft interface information
 678  * @mcast_list: a list of addresses which should _not_ be removed
 679  *
 680  * Retracts the announcement of any multicast listener from the
 681  * translation table except the ones listed in the given mcast_list.
 682  *
 683  * If mcast_list is NULL then all are retracted.
 684  */
 685 static void batadv_mcast_mla_tt_retract(struct batadv_priv *bat_priv,
 686                                         struct hlist_head *mcast_list)
 687 {
 688         struct batadv_hw_addr *mcast_entry;
 689         struct hlist_node *tmp;
 690 
 691         hlist_for_each_entry_safe(mcast_entry, tmp, &bat_priv->mcast.mla_list,
 692                                   list) {
 693                 if (mcast_list &&
 694                     batadv_mcast_mla_is_duplicate(mcast_entry->addr,
 695                                                   mcast_list))
 696                         continue;
 697 
 698                 batadv_tt_local_remove(bat_priv, mcast_entry->addr,
 699                                        BATADV_NO_FLAGS,
 700                                        "mcast TT outdated", false);
 701 
 702                 hlist_del(&mcast_entry->list);
 703                 kfree(mcast_entry);
 704         }
 705 }
 706 
 707 /**
 708  * batadv_mcast_mla_tt_add() - add multicast listener announcements
 709  * @bat_priv: the bat priv with all the soft interface information
 710  * @mcast_list: a list of addresses which are going to get added
 711  *
 712  * Adds multicast listener announcements from the given mcast_list to the
 713  * translation table if they have not been added yet.
 714  */
 715 static void batadv_mcast_mla_tt_add(struct batadv_priv *bat_priv,
 716                                     struct hlist_head *mcast_list)
 717 {
 718         struct batadv_hw_addr *mcast_entry;
 719         struct hlist_node *tmp;
 720 
 721         if (!mcast_list)
 722                 return;
 723 
 724         hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) {
 725                 if (batadv_mcast_mla_is_duplicate(mcast_entry->addr,
 726                                                   &bat_priv->mcast.mla_list))
 727                         continue;
 728 
 729                 if (!batadv_tt_local_add(bat_priv->soft_iface,
 730                                          mcast_entry->addr, BATADV_NO_FLAGS,
 731                                          BATADV_NULL_IFINDEX, BATADV_NO_MARK))
 732                         continue;
 733 
 734                 hlist_del(&mcast_entry->list);
 735                 hlist_add_head(&mcast_entry->list, &bat_priv->mcast.mla_list);
 736         }
 737 }
 738 
 739 /**
 740  * batadv_mcast_querier_log() - debug output regarding the querier status on
 741  *  link
 742  * @bat_priv: the bat priv with all the soft interface information
 743  * @str_proto: a string for the querier protocol (e.g. "IGMP" or "MLD")
 744  * @old_state: the previous querier state on our link
 745  * @new_state: the new querier state on our link
 746  *
 747  * Outputs debug messages to the logging facility with log level 'mcast'
 748  * regarding changes to the querier status on the link which are relevant
 749  * to our multicast optimizations.
 750  *
 751  * Usually this is about whether a querier appeared or vanished in
 752  * our mesh or whether the querier is in the suboptimal position of being
 753  * behind our local bridge segment: Snooping switches will directly
 754  * forward listener reports to the querier, therefore batman-adv and
 755  * the bridge will potentially not see these listeners - the querier is
 756  * potentially shadowing listeners from us then.
 757  *
 758  * This is only interesting for nodes with a bridge on top of their
 759  * soft interface.
 760  */
 761 static void
 762 batadv_mcast_querier_log(struct batadv_priv *bat_priv, char *str_proto,
 763                          struct batadv_mcast_querier_state *old_state,
 764                          struct batadv_mcast_querier_state *new_state)
 765 {
 766         if (!old_state->exists && new_state->exists)
 767                 batadv_info(bat_priv->soft_iface, "%s Querier appeared\n",
 768                             str_proto);
 769         else if (old_state->exists && !new_state->exists)
 770                 batadv_info(bat_priv->soft_iface,
 771                             "%s Querier disappeared - multicast optimizations disabled\n",
 772                             str_proto);
 773         else if (!bat_priv->mcast.mla_flags.bridged && !new_state->exists)
 774                 batadv_info(bat_priv->soft_iface,
 775                             "No %s Querier present - multicast optimizations disabled\n",
 776                             str_proto);
 777 
 778         if (new_state->exists) {
 779                 if ((!old_state->shadowing && new_state->shadowing) ||
 780                     (!old_state->exists && new_state->shadowing))
 781                         batadv_dbg(BATADV_DBG_MCAST, bat_priv,
 782                                    "%s Querier is behind our bridged segment: Might shadow listeners\n",
 783                                    str_proto);
 784                 else if (old_state->shadowing && !new_state->shadowing)
 785                         batadv_dbg(BATADV_DBG_MCAST, bat_priv,
 786                                    "%s Querier is not behind our bridged segment\n",
 787                                    str_proto);
 788         }
 789 }
 790 
 791 /**
 792  * batadv_mcast_bridge_log() - debug output for topology changes in bridged
 793  *  setups
 794  * @bat_priv: the bat priv with all the soft interface information
 795  * @new_flags: flags indicating the new multicast state
 796  *
 797  * If no bridges are ever used on this node, then this function does nothing.
 798  *
 799  * Otherwise this function outputs debug information to the 'mcast' log level
 800  * which might be relevant to our multicast optimizations.
 801  *
 802  * More precisely, it outputs information when a bridge interface is added or
 803  * removed from a soft interface. And when a bridge is present, it further
 804  * outputs information about the querier state which is relevant for the
 805  * multicast flags this node is going to set.
 806  */
 807 static void
 808 batadv_mcast_bridge_log(struct batadv_priv *bat_priv,
 809                         struct batadv_mcast_mla_flags *new_flags)
 810 {
 811         struct batadv_mcast_mla_flags *old_flags = &bat_priv->mcast.mla_flags;
 812 
 813         if (!old_flags->bridged && new_flags->bridged)
 814                 batadv_dbg(BATADV_DBG_MCAST, bat_priv,
 815                            "Bridge added: Setting Unsnoopables(U)-flag\n");
 816         else if (old_flags->bridged && !new_flags->bridged)
 817                 batadv_dbg(BATADV_DBG_MCAST, bat_priv,
 818                            "Bridge removed: Unsetting Unsnoopables(U)-flag\n");
 819 
 820         if (new_flags->bridged) {
 821                 batadv_mcast_querier_log(bat_priv, "IGMP",
 822                                          &old_flags->querier_ipv4,
 823                                          &new_flags->querier_ipv4);
 824                 batadv_mcast_querier_log(bat_priv, "MLD",
 825                                          &old_flags->querier_ipv6,
 826                                          &new_flags->querier_ipv6);
 827         }
 828 }
 829 
 830 /**
 831  * batadv_mcast_flags_logs() - output debug information about mcast flag changes
 832  * @bat_priv: the bat priv with all the soft interface information
 833  * @flags: TVLV flags indicating the new multicast state
 834  *
 835  * Whenever the multicast TVLV flags this nodes announces change this notifies
 836  * userspace via the 'mcast' log level.
 837  */
 838 static void batadv_mcast_flags_log(struct batadv_priv *bat_priv, u8 flags)
 839 {
 840         bool old_enabled = bat_priv->mcast.mla_flags.enabled;
 841         u8 old_flags = bat_priv->mcast.mla_flags.tvlv_flags;
 842         char str_old_flags[] = "[.... . ]";
 843 
 844         sprintf(str_old_flags, "[%c%c%c%s%s]",
 845                 (old_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) ? 'U' : '.',
 846                 (old_flags & BATADV_MCAST_WANT_ALL_IPV4) ? '4' : '.',
 847                 (old_flags & BATADV_MCAST_WANT_ALL_IPV6) ? '6' : '.',
 848                 !(old_flags & BATADV_MCAST_WANT_NO_RTR4) ? "R4" : ". ",
 849                 !(old_flags & BATADV_MCAST_WANT_NO_RTR6) ? "R6" : ". ");
 850 
 851         batadv_dbg(BATADV_DBG_MCAST, bat_priv,
 852                    "Changing multicast flags from '%s' to '[%c%c%c%s%s]'\n",
 853                    old_enabled ? str_old_flags : "<undefined>",
 854                    (flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) ? 'U' : '.',
 855                    (flags & BATADV_MCAST_WANT_ALL_IPV4) ? '4' : '.',
 856                    (flags & BATADV_MCAST_WANT_ALL_IPV6) ? '6' : '.',
 857                    !(flags & BATADV_MCAST_WANT_NO_RTR4) ? "R4" : ". ",
 858                    !(flags & BATADV_MCAST_WANT_NO_RTR6) ? "R6" : ". ");
 859 }
 860 
 861 /**
 862  * batadv_mcast_mla_flags_update() - update multicast flags
 863  * @bat_priv: the bat priv with all the soft interface information
 864  * @flags: flags indicating the new multicast state
 865  *
 866  * Updates the own multicast tvlv with our current multicast related settings,
 867  * capabilities and inabilities.
 868  */
 869 static void
 870 batadv_mcast_mla_flags_update(struct batadv_priv *bat_priv,
 871                               struct batadv_mcast_mla_flags *flags)
 872 {
 873         struct batadv_tvlv_mcast_data mcast_data;
 874 
 875         if (!memcmp(flags, &bat_priv->mcast.mla_flags, sizeof(*flags)))
 876                 return;
 877 
 878         batadv_mcast_bridge_log(bat_priv, flags);
 879         batadv_mcast_flags_log(bat_priv, flags->tvlv_flags);
 880 
 881         mcast_data.flags = flags->tvlv_flags;
 882         memset(mcast_data.reserved, 0, sizeof(mcast_data.reserved));
 883 
 884         batadv_tvlv_container_register(bat_priv, BATADV_TVLV_MCAST, 2,
 885                                        &mcast_data, sizeof(mcast_data));
 886 
 887         bat_priv->mcast.mla_flags = *flags;
 888 }
 889 
 890 /**
 891  * __batadv_mcast_mla_update() - update the own MLAs
 892  * @bat_priv: the bat priv with all the soft interface information
 893  *
 894  * Updates the own multicast listener announcements in the translation
 895  * table as well as the own, announced multicast tvlv container.
 896  *
 897  * Note that non-conflicting reads and writes to bat_priv->mcast.mla_list
 898  * in batadv_mcast_mla_tt_retract() and batadv_mcast_mla_tt_add() are
 899  * ensured by the non-parallel execution of the worker this function
 900  * belongs to.
 901  */
 902 static void __batadv_mcast_mla_update(struct batadv_priv *bat_priv)
 903 {
 904         struct net_device *soft_iface = bat_priv->soft_iface;
 905         struct hlist_head mcast_list = HLIST_HEAD_INIT;
 906         struct batadv_mcast_mla_flags flags;
 907         int ret;
 908 
 909         flags = batadv_mcast_mla_flags_get(bat_priv);
 910 
 911         ret = batadv_mcast_mla_softif_get(soft_iface, &mcast_list, &flags);
 912         if (ret < 0)
 913                 goto out;
 914 
 915         ret = batadv_mcast_mla_bridge_get(soft_iface, &mcast_list, &flags);
 916         if (ret < 0)
 917                 goto out;
 918 
 919         spin_lock(&bat_priv->mcast.mla_lock);
 920         batadv_mcast_mla_tt_retract(bat_priv, &mcast_list);
 921         batadv_mcast_mla_tt_add(bat_priv, &mcast_list);
 922         batadv_mcast_mla_flags_update(bat_priv, &flags);
 923         spin_unlock(&bat_priv->mcast.mla_lock);
 924 
 925 out:
 926         batadv_mcast_mla_list_free(&mcast_list);
 927 }
 928 
 929 /**
 930  * batadv_mcast_mla_update() - update the own MLAs
 931  * @work: kernel work struct
 932  *
 933  * Updates the own multicast listener announcements in the translation
 934  * table as well as the own, announced multicast tvlv container.
 935  *
 936  * In the end, reschedules the work timer.
 937  */
 938 static void batadv_mcast_mla_update(struct work_struct *work)
 939 {
 940         struct delayed_work *delayed_work;
 941         struct batadv_priv_mcast *priv_mcast;
 942         struct batadv_priv *bat_priv;
 943 
 944         delayed_work = to_delayed_work(work);
 945         priv_mcast = container_of(delayed_work, struct batadv_priv_mcast, work);
 946         bat_priv = container_of(priv_mcast, struct batadv_priv, mcast);
 947 
 948         __batadv_mcast_mla_update(bat_priv);
 949         batadv_mcast_start_timer(bat_priv);
 950 }
 951 
 952 /**
 953  * batadv_mcast_is_report_ipv4() - check for IGMP reports
 954  * @skb: the ethernet frame destined for the mesh
 955  *
 956  * This call might reallocate skb data.
 957  *
 958  * Checks whether the given frame is a valid IGMP report.
 959  *
 960  * Return: If so then true, otherwise false.
 961  */
 962 static bool batadv_mcast_is_report_ipv4(struct sk_buff *skb)
 963 {
 964         if (ip_mc_check_igmp(skb) < 0)
 965                 return false;
 966 
 967         switch (igmp_hdr(skb)->type) {
 968         case IGMP_HOST_MEMBERSHIP_REPORT:
 969         case IGMPV2_HOST_MEMBERSHIP_REPORT:
 970         case IGMPV3_HOST_MEMBERSHIP_REPORT:
 971                 return true;
 972         }
 973 
 974         return false;
 975 }
 976 
 977 /**
 978  * batadv_mcast_forw_mode_check_ipv4() - check for optimized forwarding
 979  *  potential
 980  * @bat_priv: the bat priv with all the soft interface information
 981  * @skb: the IPv4 packet to check
 982  * @is_unsnoopable: stores whether the destination is snoopable
 983  * @is_routable: stores whether the destination is routable
 984  *
 985  * Checks whether the given IPv4 packet has the potential to be forwarded with a
 986  * mode more optimal than classic flooding.
 987  *
 988  * Return: If so then 0. Otherwise -EINVAL or -ENOMEM in case of memory
 989  * allocation failure.
 990  */
 991 static int batadv_mcast_forw_mode_check_ipv4(struct batadv_priv *bat_priv,
 992                                              struct sk_buff *skb,
 993                                              bool *is_unsnoopable,
 994                                              int *is_routable)
 995 {
 996         struct iphdr *iphdr;
 997 
 998         /* We might fail due to out-of-memory -> drop it */
 999         if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*iphdr)))
1000                 return -ENOMEM;
1001 
1002         if (batadv_mcast_is_report_ipv4(skb))
1003                 return -EINVAL;
1004 
1005         iphdr = ip_hdr(skb);
1006 
1007         /* link-local multicast listeners behind a bridge are
1008          * not snoopable (see RFC4541, section 2.1.2.2)
1009          */
1010         if (ipv4_is_local_multicast(iphdr->daddr))
1011                 *is_unsnoopable = true;
1012         else
1013                 *is_routable = ETH_P_IP;
1014 
1015         return 0;
1016 }
1017 
1018 /**
1019  * batadv_mcast_is_report_ipv6() - check for MLD reports
1020  * @skb: the ethernet frame destined for the mesh
1021  *
1022  * This call might reallocate skb data.
1023  *
1024  * Checks whether the given frame is a valid MLD report.
1025  *
1026  * Return: If so then true, otherwise false.
1027  */
1028 static bool batadv_mcast_is_report_ipv6(struct sk_buff *skb)
1029 {
1030         if (ipv6_mc_check_mld(skb) < 0)
1031                 return false;
1032 
1033         switch (icmp6_hdr(skb)->icmp6_type) {
1034         case ICMPV6_MGM_REPORT:
1035         case ICMPV6_MLD2_REPORT:
1036                 return true;
1037         }
1038 
1039         return false;
1040 }
1041 
1042 /**
1043  * batadv_mcast_forw_mode_check_ipv6() - check for optimized forwarding
1044  *  potential
1045  * @bat_priv: the bat priv with all the soft interface information
1046  * @skb: the IPv6 packet to check
1047  * @is_unsnoopable: stores whether the destination is snoopable
1048  * @is_routable: stores whether the destination is routable
1049  *
1050  * Checks whether the given IPv6 packet has the potential to be forwarded with a
1051  * mode more optimal than classic flooding.
1052  *
1053  * Return: If so then 0. Otherwise -EINVAL is or -ENOMEM if we are out of memory
1054  */
1055 static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv,
1056                                              struct sk_buff *skb,
1057                                              bool *is_unsnoopable,
1058                                              int *is_routable)
1059 {
1060         struct ipv6hdr *ip6hdr;
1061 
1062         /* We might fail due to out-of-memory -> drop it */
1063         if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*ip6hdr)))
1064                 return -ENOMEM;
1065 
1066         if (batadv_mcast_is_report_ipv6(skb))
1067                 return -EINVAL;
1068 
1069         ip6hdr = ipv6_hdr(skb);
1070 
1071         if (IPV6_ADDR_MC_SCOPE(&ip6hdr->daddr) < IPV6_ADDR_SCOPE_LINKLOCAL)
1072                 return -EINVAL;
1073 
1074         /* link-local-all-nodes multicast listeners behind a bridge are
1075          * not snoopable (see RFC4541, section 3, paragraph 3)
1076          */
1077         if (ipv6_addr_is_ll_all_nodes(&ip6hdr->daddr))
1078                 *is_unsnoopable = true;
1079         else if (IPV6_ADDR_MC_SCOPE(&ip6hdr->daddr) > IPV6_ADDR_SCOPE_LINKLOCAL)
1080                 *is_routable = ETH_P_IPV6;
1081 
1082         return 0;
1083 }
1084 
1085 /**
1086  * batadv_mcast_forw_mode_check() - check for optimized forwarding potential
1087  * @bat_priv: the bat priv with all the soft interface information
1088  * @skb: the multicast frame to check
1089  * @is_unsnoopable: stores whether the destination is snoopable
1090  * @is_routable: stores whether the destination is routable
1091  *
1092  * Checks whether the given multicast ethernet frame has the potential to be
1093  * forwarded with a mode more optimal than classic flooding.
1094  *
1095  * Return: If so then 0. Otherwise -EINVAL is or -ENOMEM if we are out of memory
1096  */
1097 static int batadv_mcast_forw_mode_check(struct batadv_priv *bat_priv,
1098                                         struct sk_buff *skb,
1099                                         bool *is_unsnoopable,
1100                                         int *is_routable)
1101 {
1102         struct ethhdr *ethhdr = eth_hdr(skb);
1103 
1104         if (!atomic_read(&bat_priv->multicast_mode))
1105                 return -EINVAL;
1106 
1107         switch (ntohs(ethhdr->h_proto)) {
1108         case ETH_P_IP:
1109                 return batadv_mcast_forw_mode_check_ipv4(bat_priv, skb,
1110                                                          is_unsnoopable,
1111                                                          is_routable);
1112         case ETH_P_IPV6:
1113                 if (!IS_ENABLED(CONFIG_IPV6))
1114                         return -EINVAL;
1115 
1116                 return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb,
1117                                                          is_unsnoopable,
1118                                                          is_routable);
1119         default:
1120                 return -EINVAL;
1121         }
1122 }
1123 
1124 /**
1125  * batadv_mcast_forw_want_all_ip_count() - count nodes with unspecific mcast
1126  *  interest
1127  * @bat_priv: the bat priv with all the soft interface information
1128  * @ethhdr: ethernet header of a packet
1129  *
1130  * Return: the number of nodes which want all IPv4 multicast traffic if the
1131  * given ethhdr is from an IPv4 packet or the number of nodes which want all
1132  * IPv6 traffic if it matches an IPv6 packet.
1133  */
1134 static int batadv_mcast_forw_want_all_ip_count(struct batadv_priv *bat_priv,
1135                                                struct ethhdr *ethhdr)
1136 {
1137         switch (ntohs(ethhdr->h_proto)) {
1138         case ETH_P_IP:
1139                 return atomic_read(&bat_priv->mcast.num_want_all_ipv4);
1140         case ETH_P_IPV6:
1141                 return atomic_read(&bat_priv->mcast.num_want_all_ipv6);
1142         default:
1143                 /* we shouldn't be here... */
1144                 return 0;
1145         }
1146 }
1147 
1148 /**
1149  * batadv_mcast_forw_rtr_count() - count nodes with a multicast router
1150  * @bat_priv: the bat priv with all the soft interface information
1151  * @protocol: the ethernet protocol type to count multicast routers for
1152  *
1153  * Return: the number of nodes which want all routable IPv4 multicast traffic
1154  * if the protocol is ETH_P_IP or the number of nodes which want all routable
1155  * IPv6 traffic if the protocol is ETH_P_IPV6. Otherwise returns 0.
1156  */
1157 
1158 static int batadv_mcast_forw_rtr_count(struct batadv_priv *bat_priv,
1159                                        int protocol)
1160 {
1161         switch (protocol) {
1162         case ETH_P_IP:
1163                 return atomic_read(&bat_priv->mcast.num_want_all_rtr4);
1164         case ETH_P_IPV6:
1165                 return atomic_read(&bat_priv->mcast.num_want_all_rtr6);
1166         default:
1167                 return 0;
1168         }
1169 }
1170 
1171 /**
1172  * batadv_mcast_forw_tt_node_get() - get a multicast tt node
1173  * @bat_priv: the bat priv with all the soft interface information
1174  * @ethhdr: the ether header containing the multicast destination
1175  *
1176  * Return: an orig_node matching the multicast address provided by ethhdr
1177  * via a translation table lookup. This increases the returned nodes refcount.
1178  */
1179 static struct batadv_orig_node *
1180 batadv_mcast_forw_tt_node_get(struct batadv_priv *bat_priv,
1181                               struct ethhdr *ethhdr)
1182 {
1183         return batadv_transtable_search(bat_priv, NULL, ethhdr->h_dest,
1184                                         BATADV_NO_FLAGS);
1185 }
1186 
1187 /**
1188  * batadv_mcast_forw_ipv4_node_get() - get a node with an ipv4 flag
1189  * @bat_priv: the bat priv with all the soft interface information
1190  *
1191  * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_IPV4 flag set and
1192  * increases its refcount.
1193  */
1194 static struct batadv_orig_node *
1195 batadv_mcast_forw_ipv4_node_get(struct batadv_priv *bat_priv)
1196 {
1197         struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
1198 
1199         rcu_read_lock();
1200         hlist_for_each_entry_rcu(tmp_orig_node,
1201                                  &bat_priv->mcast.want_all_ipv4_list,
1202                                  mcast_want_all_ipv4_node) {
1203                 if (!kref_get_unless_zero(&tmp_orig_node->refcount))
1204                         continue;
1205 
1206                 orig_node = tmp_orig_node;
1207                 break;
1208         }
1209         rcu_read_unlock();
1210 
1211         return orig_node;
1212 }
1213 
1214 /**
1215  * batadv_mcast_forw_ipv6_node_get() - get a node with an ipv6 flag
1216  * @bat_priv: the bat priv with all the soft interface information
1217  *
1218  * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_IPV6 flag set
1219  * and increases its refcount.
1220  */
1221 static struct batadv_orig_node *
1222 batadv_mcast_forw_ipv6_node_get(struct batadv_priv *bat_priv)
1223 {
1224         struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
1225 
1226         rcu_read_lock();
1227         hlist_for_each_entry_rcu(tmp_orig_node,
1228                                  &bat_priv->mcast.want_all_ipv6_list,
1229                                  mcast_want_all_ipv6_node) {
1230                 if (!kref_get_unless_zero(&tmp_orig_node->refcount))
1231                         continue;
1232 
1233                 orig_node = tmp_orig_node;
1234                 break;
1235         }
1236         rcu_read_unlock();
1237 
1238         return orig_node;
1239 }
1240 
1241 /**
1242  * batadv_mcast_forw_ip_node_get() - get a node with an ipv4/ipv6 flag
1243  * @bat_priv: the bat priv with all the soft interface information
1244  * @ethhdr: an ethernet header to determine the protocol family from
1245  *
1246  * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_IPV4 or
1247  * BATADV_MCAST_WANT_ALL_IPV6 flag, depending on the provided ethhdr, set and
1248  * increases its refcount.
1249  */
1250 static struct batadv_orig_node *
1251 batadv_mcast_forw_ip_node_get(struct batadv_priv *bat_priv,
1252                               struct ethhdr *ethhdr)
1253 {
1254         switch (ntohs(ethhdr->h_proto)) {
1255         case ETH_P_IP:
1256                 return batadv_mcast_forw_ipv4_node_get(bat_priv);
1257         case ETH_P_IPV6:
1258                 return batadv_mcast_forw_ipv6_node_get(bat_priv);
1259         default:
1260                 /* we shouldn't be here... */
1261                 return NULL;
1262         }
1263 }
1264 
1265 /**
1266  * batadv_mcast_forw_unsnoop_node_get() - get a node with an unsnoopable flag
1267  * @bat_priv: the bat priv with all the soft interface information
1268  *
1269  * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag
1270  * set and increases its refcount.
1271  */
1272 static struct batadv_orig_node *
1273 batadv_mcast_forw_unsnoop_node_get(struct batadv_priv *bat_priv)
1274 {
1275         struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
1276 
1277         rcu_read_lock();
1278         hlist_for_each_entry_rcu(tmp_orig_node,
1279                                  &bat_priv->mcast.want_all_unsnoopables_list,
1280                                  mcast_want_all_unsnoopables_node) {
1281                 if (!kref_get_unless_zero(&tmp_orig_node->refcount))
1282                         continue;
1283 
1284                 orig_node = tmp_orig_node;
1285                 break;
1286         }
1287         rcu_read_unlock();
1288 
1289         return orig_node;
1290 }
1291 
1292 /**
1293  * batadv_mcast_forw_rtr4_node_get() - get a node with an ipv4 mcast router flag
1294  * @bat_priv: the bat priv with all the soft interface information
1295  *
1296  * Return: an orig_node which has the BATADV_MCAST_WANT_NO_RTR4 flag unset and
1297  * increases its refcount.
1298  */
1299 static struct batadv_orig_node *
1300 batadv_mcast_forw_rtr4_node_get(struct batadv_priv *bat_priv)
1301 {
1302         struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
1303 
1304         rcu_read_lock();
1305         hlist_for_each_entry_rcu(tmp_orig_node,
1306                                  &bat_priv->mcast.want_all_rtr4_list,
1307                                  mcast_want_all_rtr4_node) {
1308                 if (!kref_get_unless_zero(&tmp_orig_node->refcount))
1309                         continue;
1310 
1311                 orig_node = tmp_orig_node;
1312                 break;
1313         }
1314         rcu_read_unlock();
1315 
1316         return orig_node;
1317 }
1318 
1319 /**
1320  * batadv_mcast_forw_rtr6_node_get() - get a node with an ipv6 mcast router flag
1321  * @bat_priv: the bat priv with all the soft interface information
1322  *
1323  * Return: an orig_node which has the BATADV_MCAST_WANT_NO_RTR6 flag unset
1324  * and increases its refcount.
1325  */
1326 static struct batadv_orig_node *
1327 batadv_mcast_forw_rtr6_node_get(struct batadv_priv *bat_priv)
1328 {
1329         struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
1330 
1331         rcu_read_lock();
1332         hlist_for_each_entry_rcu(tmp_orig_node,
1333                                  &bat_priv->mcast.want_all_rtr6_list,
1334                                  mcast_want_all_rtr6_node) {
1335                 if (!kref_get_unless_zero(&tmp_orig_node->refcount))
1336                         continue;
1337 
1338                 orig_node = tmp_orig_node;
1339                 break;
1340         }
1341         rcu_read_unlock();
1342 
1343         return orig_node;
1344 }
1345 
1346 /**
1347  * batadv_mcast_forw_rtr_node_get() - get a node with an ipv4/ipv6 router flag
1348  * @bat_priv: the bat priv with all the soft interface information
1349  * @ethhdr: an ethernet header to determine the protocol family from
1350  *
1351  * Return: an orig_node which has no BATADV_MCAST_WANT_NO_RTR4 or
1352  * BATADV_MCAST_WANT_NO_RTR6 flag, depending on the provided ethhdr, set and
1353  * increases its refcount.
1354  */
1355 static struct batadv_orig_node *
1356 batadv_mcast_forw_rtr_node_get(struct batadv_priv *bat_priv,
1357                                struct ethhdr *ethhdr)
1358 {
1359         switch (ntohs(ethhdr->h_proto)) {
1360         case ETH_P_IP:
1361                 return batadv_mcast_forw_rtr4_node_get(bat_priv);
1362         case ETH_P_IPV6:
1363                 return batadv_mcast_forw_rtr6_node_get(bat_priv);
1364         default:
1365                 /* we shouldn't be here... */
1366                 return NULL;
1367         }
1368 }
1369 
1370 /**
1371  * batadv_mcast_forw_mode() - check on how to forward a multicast packet
1372  * @bat_priv: the bat priv with all the soft interface information
1373  * @skb: The multicast packet to check
1374  * @orig: an originator to be set to forward the skb to
1375  *
1376  * Return: the forwarding mode as enum batadv_forw_mode and in case of
1377  * BATADV_FORW_SINGLE set the orig to the single originator the skb
1378  * should be forwarded to.
1379  */
1380 enum batadv_forw_mode
1381 batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb,
1382                        struct batadv_orig_node **orig)
1383 {
1384         int ret, tt_count, ip_count, unsnoop_count, total_count;
1385         bool is_unsnoopable = false;
1386         unsigned int mcast_fanout;
1387         struct ethhdr *ethhdr;
1388         int is_routable = 0;
1389         int rtr_count = 0;
1390 
1391         ret = batadv_mcast_forw_mode_check(bat_priv, skb, &is_unsnoopable,
1392                                            &is_routable);
1393         if (ret == -ENOMEM)
1394                 return BATADV_FORW_NONE;
1395         else if (ret < 0)
1396                 return BATADV_FORW_ALL;
1397 
1398         ethhdr = eth_hdr(skb);
1399 
1400         tt_count = batadv_tt_global_hash_count(bat_priv, ethhdr->h_dest,
1401                                                BATADV_NO_FLAGS);
1402         ip_count = batadv_mcast_forw_want_all_ip_count(bat_priv, ethhdr);
1403         unsnoop_count = !is_unsnoopable ? 0 :
1404                         atomic_read(&bat_priv->mcast.num_want_all_unsnoopables);
1405         rtr_count = batadv_mcast_forw_rtr_count(bat_priv, is_routable);
1406 
1407         total_count = tt_count + ip_count + unsnoop_count + rtr_count;
1408 
1409         switch (total_count) {
1410         case 1:
1411                 if (tt_count)
1412                         *orig = batadv_mcast_forw_tt_node_get(bat_priv, ethhdr);
1413                 else if (ip_count)
1414                         *orig = batadv_mcast_forw_ip_node_get(bat_priv, ethhdr);
1415                 else if (unsnoop_count)
1416                         *orig = batadv_mcast_forw_unsnoop_node_get(bat_priv);
1417                 else if (rtr_count)
1418                         *orig = batadv_mcast_forw_rtr_node_get(bat_priv,
1419                                                                ethhdr);
1420 
1421                 if (*orig)
1422                         return BATADV_FORW_SINGLE;
1423 
1424                 /* fall through */
1425         case 0:
1426                 return BATADV_FORW_NONE;
1427         default:
1428                 mcast_fanout = atomic_read(&bat_priv->multicast_fanout);
1429 
1430                 if (!unsnoop_count && total_count <= mcast_fanout)
1431                         return BATADV_FORW_SOME;
1432         }
1433 
1434         return BATADV_FORW_ALL;
1435 }
1436 
1437 /**
1438  * batadv_mcast_forw_tt() - forwards a packet to multicast listeners
1439  * @bat_priv: the bat priv with all the soft interface information
1440  * @skb: the multicast packet to transmit
1441  * @vid: the vlan identifier
1442  *
1443  * Sends copies of a frame with multicast destination to any multicast
1444  * listener registered in the translation table. A transmission is performed
1445  * via a batman-adv unicast packet for each such destination node.
1446  *
1447  * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
1448  * otherwise.
1449  */
1450 static int
1451 batadv_mcast_forw_tt(struct batadv_priv *bat_priv, struct sk_buff *skb,
1452                      unsigned short vid)
1453 {
1454         int ret = NET_XMIT_SUCCESS;
1455         struct sk_buff *newskb;
1456 
1457         struct batadv_tt_orig_list_entry *orig_entry;
1458 
1459         struct batadv_tt_global_entry *tt_global;
1460         const u8 *addr = eth_hdr(skb)->h_dest;
1461 
1462         tt_global = batadv_tt_global_hash_find(bat_priv, addr, vid);
1463         if (!tt_global)
1464                 goto out;
1465 
1466         rcu_read_lock();
1467         hlist_for_each_entry_rcu(orig_entry, &tt_global->orig_list, list) {
1468                 newskb = skb_copy(skb, GFP_ATOMIC);
1469                 if (!newskb) {
1470                         ret = NET_XMIT_DROP;
1471                         break;
1472                 }
1473 
1474                 batadv_send_skb_unicast(bat_priv, newskb, BATADV_UNICAST, 0,
1475                                         orig_entry->orig_node, vid);
1476         }
1477         rcu_read_unlock();
1478 
1479         batadv_tt_global_entry_put(tt_global);
1480 
1481 out:
1482         return ret;
1483 }
1484 
1485 /**
1486  * batadv_mcast_forw_want_all_ipv4() - forward to nodes with want-all-ipv4
1487  * @bat_priv: the bat priv with all the soft interface information
1488  * @skb: the multicast packet to transmit
1489  * @vid: the vlan identifier
1490  *
1491  * Sends copies of a frame with multicast destination to any node with a
1492  * BATADV_MCAST_WANT_ALL_IPV4 flag set. A transmission is performed via a
1493  * batman-adv unicast packet for each such destination node.
1494  *
1495  * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
1496  * otherwise.
1497  */
1498 static int
1499 batadv_mcast_forw_want_all_ipv4(struct batadv_priv *bat_priv,
1500                                 struct sk_buff *skb, unsigned short vid)
1501 {
1502         struct batadv_orig_node *orig_node;
1503         int ret = NET_XMIT_SUCCESS;
1504         struct sk_buff *newskb;
1505 
1506         rcu_read_lock();
1507         hlist_for_each_entry_rcu(orig_node,
1508                                  &bat_priv->mcast.want_all_ipv4_list,
1509                                  mcast_want_all_ipv4_node) {
1510                 newskb = skb_copy(skb, GFP_ATOMIC);
1511                 if (!newskb) {
1512                         ret = NET_XMIT_DROP;
1513                         break;
1514                 }
1515 
1516                 batadv_send_skb_unicast(bat_priv, newskb, BATADV_UNICAST, 0,
1517                                         orig_node, vid);
1518         }
1519         rcu_read_unlock();
1520         return ret;
1521 }
1522 
1523 /**
1524  * batadv_mcast_forw_want_all_ipv6() - forward to nodes with want-all-ipv6
1525  * @bat_priv: the bat priv with all the soft interface information
1526  * @skb: The multicast packet to transmit
1527  * @vid: the vlan identifier
1528  *
1529  * Sends copies of a frame with multicast destination to any node with a
1530  * BATADV_MCAST_WANT_ALL_IPV6 flag set. A transmission is performed via a
1531  * batman-adv unicast packet for each such destination node.
1532  *
1533  * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
1534  * otherwise.
1535  */
1536 static int
1537 batadv_mcast_forw_want_all_ipv6(struct batadv_priv *bat_priv,
1538                                 struct sk_buff *skb, unsigned short vid)
1539 {
1540         struct batadv_orig_node *orig_node;
1541         int ret = NET_XMIT_SUCCESS;
1542         struct sk_buff *newskb;
1543 
1544         rcu_read_lock();
1545         hlist_for_each_entry_rcu(orig_node,
1546                                  &bat_priv->mcast.want_all_ipv6_list,
1547                                  mcast_want_all_ipv6_node) {
1548                 newskb = skb_copy(skb, GFP_ATOMIC);
1549                 if (!newskb) {
1550                         ret = NET_XMIT_DROP;
1551                         break;
1552                 }
1553 
1554                 batadv_send_skb_unicast(bat_priv, newskb, BATADV_UNICAST, 0,
1555                                         orig_node, vid);
1556         }
1557         rcu_read_unlock();
1558         return ret;
1559 }
1560 
1561 /**
1562  * batadv_mcast_forw_want_all() - forward packet to nodes in a want-all list
1563  * @bat_priv: the bat priv with all the soft interface information
1564  * @skb: the multicast packet to transmit
1565  * @vid: the vlan identifier
1566  *
1567  * Sends copies of a frame with multicast destination to any node with a
1568  * BATADV_MCAST_WANT_ALL_IPV4 or BATADV_MCAST_WANT_ALL_IPV6 flag set. A
1569  * transmission is performed via a batman-adv unicast packet for each such
1570  * destination node.
1571  *
1572  * Return: NET_XMIT_DROP on memory allocation failure or if the protocol family
1573  * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise.
1574  */
1575 static int
1576 batadv_mcast_forw_want_all(struct batadv_priv *bat_priv,
1577                            struct sk_buff *skb, unsigned short vid)
1578 {
1579         switch (ntohs(eth_hdr(skb)->h_proto)) {
1580         case ETH_P_IP:
1581                 return batadv_mcast_forw_want_all_ipv4(bat_priv, skb, vid);
1582         case ETH_P_IPV6:
1583                 return batadv_mcast_forw_want_all_ipv6(bat_priv, skb, vid);
1584         default:
1585                 /* we shouldn't be here... */
1586                 return NET_XMIT_DROP;
1587         }
1588 }
1589 
1590 /**
1591  * batadv_mcast_forw_want_all_rtr4() - forward to nodes with want-all-rtr4
1592  * @bat_priv: the bat priv with all the soft interface information
1593  * @skb: the multicast packet to transmit
1594  * @vid: the vlan identifier
1595  *
1596  * Sends copies of a frame with multicast destination to any node with a
1597  * BATADV_MCAST_WANT_NO_RTR4 flag unset. A transmission is performed via a
1598  * batman-adv unicast packet for each such destination node.
1599  *
1600  * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
1601  * otherwise.
1602  */
1603 static int
1604 batadv_mcast_forw_want_all_rtr4(struct batadv_priv *bat_priv,
1605                                 struct sk_buff *skb, unsigned short vid)
1606 {
1607         struct batadv_orig_node *orig_node;
1608         int ret = NET_XMIT_SUCCESS;
1609         struct sk_buff *newskb;
1610 
1611         rcu_read_lock();
1612         hlist_for_each_entry_rcu(orig_node,
1613                                  &bat_priv->mcast.want_all_rtr4_list,
1614                                  mcast_want_all_rtr4_node) {
1615                 newskb = skb_copy(skb, GFP_ATOMIC);
1616                 if (!newskb) {
1617                         ret = NET_XMIT_DROP;
1618                         break;
1619                 }
1620 
1621                 batadv_send_skb_unicast(bat_priv, newskb, BATADV_UNICAST, 0,
1622                                         orig_node, vid);
1623         }
1624         rcu_read_unlock();
1625         return ret;
1626 }
1627 
1628 /**
1629  * batadv_mcast_forw_want_all_rtr6() - forward to nodes with want-all-rtr6
1630  * @bat_priv: the bat priv with all the soft interface information
1631  * @skb: The multicast packet to transmit
1632  * @vid: the vlan identifier
1633  *
1634  * Sends copies of a frame with multicast destination to any node with a
1635  * BATADV_MCAST_WANT_NO_RTR6 flag unset. A transmission is performed via a
1636  * batman-adv unicast packet for each such destination node.
1637  *
1638  * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
1639  * otherwise.
1640  */
1641 static int
1642 batadv_mcast_forw_want_all_rtr6(struct batadv_priv *bat_priv,
1643                                 struct sk_buff *skb, unsigned short vid)
1644 {
1645         struct batadv_orig_node *orig_node;
1646         int ret = NET_XMIT_SUCCESS;
1647         struct sk_buff *newskb;
1648 
1649         rcu_read_lock();
1650         hlist_for_each_entry_rcu(orig_node,
1651                                  &bat_priv->mcast.want_all_rtr6_list,
1652                                  mcast_want_all_rtr6_node) {
1653                 newskb = skb_copy(skb, GFP_ATOMIC);
1654                 if (!newskb) {
1655                         ret = NET_XMIT_DROP;
1656                         break;
1657                 }
1658 
1659                 batadv_send_skb_unicast(bat_priv, newskb, BATADV_UNICAST, 0,
1660                                         orig_node, vid);
1661         }
1662         rcu_read_unlock();
1663         return ret;
1664 }
1665 
1666 /**
1667  * batadv_mcast_forw_want_rtr() - forward packet to nodes in a want-all-rtr list
1668  * @bat_priv: the bat priv with all the soft interface information
1669  * @skb: the multicast packet to transmit
1670  * @vid: the vlan identifier
1671  *
1672  * Sends copies of a frame with multicast destination to any node with a
1673  * BATADV_MCAST_WANT_NO_RTR4 or BATADV_MCAST_WANT_NO_RTR6 flag unset. A
1674  * transmission is performed via a batman-adv unicast packet for each such
1675  * destination node.
1676  *
1677  * Return: NET_XMIT_DROP on memory allocation failure or if the protocol family
1678  * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise.
1679  */
1680 static int
1681 batadv_mcast_forw_want_rtr(struct batadv_priv *bat_priv,
1682                            struct sk_buff *skb, unsigned short vid)
1683 {
1684         switch (ntohs(eth_hdr(skb)->h_proto)) {
1685         case ETH_P_IP:
1686                 return batadv_mcast_forw_want_all_rtr4(bat_priv, skb, vid);
1687         case ETH_P_IPV6:
1688                 return batadv_mcast_forw_want_all_rtr6(bat_priv, skb, vid);
1689         default:
1690                 /* we shouldn't be here... */
1691                 return NET_XMIT_DROP;
1692         }
1693 }
1694 
1695 /**
1696  * batadv_mcast_forw_send() - send packet to any detected multicast recpient
1697  * @bat_priv: the bat priv with all the soft interface information
1698  * @skb: the multicast packet to transmit
1699  * @vid: the vlan identifier
1700  *
1701  * Sends copies of a frame with multicast destination to any node that signaled
1702  * interest in it, that is either via the translation table or the according
1703  * want-all flags. A transmission is performed via a batman-adv unicast packet
1704  * for each such destination node.
1705  *
1706  * The given skb is consumed/freed.
1707  *
1708  * Return: NET_XMIT_DROP on memory allocation failure or if the protocol family
1709  * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise.
1710  */
1711 int batadv_mcast_forw_send(struct batadv_priv *bat_priv, struct sk_buff *skb,
1712                            unsigned short vid)
1713 {
1714         int ret;
1715 
1716         ret = batadv_mcast_forw_tt(bat_priv, skb, vid);
1717         if (ret != NET_XMIT_SUCCESS) {
1718                 kfree_skb(skb);
1719                 return ret;
1720         }
1721 
1722         ret = batadv_mcast_forw_want_all(bat_priv, skb, vid);
1723         if (ret != NET_XMIT_SUCCESS) {
1724                 kfree_skb(skb);
1725                 return ret;
1726         }
1727 
1728         ret = batadv_mcast_forw_want_rtr(bat_priv, skb, vid);
1729         if (ret != NET_XMIT_SUCCESS) {
1730                 kfree_skb(skb);
1731                 return ret;
1732         }
1733 
1734         consume_skb(skb);
1735         return ret;
1736 }
1737 
1738 /**
1739  * batadv_mcast_want_unsnoop_update() - update unsnoop counter and list
1740  * @bat_priv: the bat priv with all the soft interface information
1741  * @orig: the orig_node which multicast state might have changed of
1742  * @mcast_flags: flags indicating the new multicast state
1743  *
1744  * If the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag of this originator,
1745  * orig, has toggled then this method updates counter and list accordingly.
1746  *
1747  * Caller needs to hold orig->mcast_handler_lock.
1748  */
1749 static void batadv_mcast_want_unsnoop_update(struct batadv_priv *bat_priv,
1750                                              struct batadv_orig_node *orig,
1751                                              u8 mcast_flags)
1752 {
1753         struct hlist_node *node = &orig->mcast_want_all_unsnoopables_node;
1754         struct hlist_head *head = &bat_priv->mcast.want_all_unsnoopables_list;
1755 
1756         lockdep_assert_held(&orig->mcast_handler_lock);
1757 
1758         /* switched from flag unset to set */
1759         if (mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
1760             !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES)) {
1761                 atomic_inc(&bat_priv->mcast.num_want_all_unsnoopables);
1762 
1763                 spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1764                 /* flag checks above + mcast_handler_lock prevents this */
1765                 WARN_ON(!hlist_unhashed(node));
1766 
1767                 hlist_add_head_rcu(node, head);
1768                 spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1769         /* switched from flag set to unset */
1770         } else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) &&
1771                    orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) {
1772                 atomic_dec(&bat_priv->mcast.num_want_all_unsnoopables);
1773 
1774                 spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1775                 /* flag checks above + mcast_handler_lock prevents this */
1776                 WARN_ON(hlist_unhashed(node));
1777 
1778                 hlist_del_init_rcu(node);
1779                 spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1780         }
1781 }
1782 
1783 /**
1784  * batadv_mcast_want_ipv4_update() - update want-all-ipv4 counter and list
1785  * @bat_priv: the bat priv with all the soft interface information
1786  * @orig: the orig_node which multicast state might have changed of
1787  * @mcast_flags: flags indicating the new multicast state
1788  *
1789  * If the BATADV_MCAST_WANT_ALL_IPV4 flag of this originator, orig, has
1790  * toggled then this method updates counter and list accordingly.
1791  *
1792  * Caller needs to hold orig->mcast_handler_lock.
1793  */
1794 static void batadv_mcast_want_ipv4_update(struct batadv_priv *bat_priv,
1795                                           struct batadv_orig_node *orig,
1796                                           u8 mcast_flags)
1797 {
1798         struct hlist_node *node = &orig->mcast_want_all_ipv4_node;
1799         struct hlist_head *head = &bat_priv->mcast.want_all_ipv4_list;
1800 
1801         lockdep_assert_held(&orig->mcast_handler_lock);
1802 
1803         /* switched from flag unset to set */
1804         if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV4 &&
1805             !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4)) {
1806                 atomic_inc(&bat_priv->mcast.num_want_all_ipv4);
1807 
1808                 spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1809                 /* flag checks above + mcast_handler_lock prevents this */
1810                 WARN_ON(!hlist_unhashed(node));
1811 
1812                 hlist_add_head_rcu(node, head);
1813                 spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1814         /* switched from flag set to unset */
1815         } else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) &&
1816                    orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) {
1817                 atomic_dec(&bat_priv->mcast.num_want_all_ipv4);
1818 
1819                 spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1820                 /* flag checks above + mcast_handler_lock prevents this */
1821                 WARN_ON(hlist_unhashed(node));
1822 
1823                 hlist_del_init_rcu(node);
1824                 spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1825         }
1826 }
1827 
1828 /**
1829  * batadv_mcast_want_ipv6_update() - update want-all-ipv6 counter and list
1830  * @bat_priv: the bat priv with all the soft interface information
1831  * @orig: the orig_node which multicast state might have changed of
1832  * @mcast_flags: flags indicating the new multicast state
1833  *
1834  * If the BATADV_MCAST_WANT_ALL_IPV6 flag of this originator, orig, has
1835  * toggled then this method updates counter and list accordingly.
1836  *
1837  * Caller needs to hold orig->mcast_handler_lock.
1838  */
1839 static void batadv_mcast_want_ipv6_update(struct batadv_priv *bat_priv,
1840                                           struct batadv_orig_node *orig,
1841                                           u8 mcast_flags)
1842 {
1843         struct hlist_node *node = &orig->mcast_want_all_ipv6_node;
1844         struct hlist_head *head = &bat_priv->mcast.want_all_ipv6_list;
1845 
1846         lockdep_assert_held(&orig->mcast_handler_lock);
1847 
1848         /* switched from flag unset to set */
1849         if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV6 &&
1850             !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6)) {
1851                 atomic_inc(&bat_priv->mcast.num_want_all_ipv6);
1852 
1853                 spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1854                 /* flag checks above + mcast_handler_lock prevents this */
1855                 WARN_ON(!hlist_unhashed(node));
1856 
1857                 hlist_add_head_rcu(node, head);
1858                 spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1859         /* switched from flag set to unset */
1860         } else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) &&
1861                    orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) {
1862                 atomic_dec(&bat_priv->mcast.num_want_all_ipv6);
1863 
1864                 spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1865                 /* flag checks above + mcast_handler_lock prevents this */
1866                 WARN_ON(hlist_unhashed(node));
1867 
1868                 hlist_del_init_rcu(node);
1869                 spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1870         }
1871 }
1872 
1873 /**
1874  * batadv_mcast_want_rtr4_update() - update want-all-rtr4 counter and list
1875  * @bat_priv: the bat priv with all the soft interface information
1876  * @orig: the orig_node which multicast state might have changed of
1877  * @mcast_flags: flags indicating the new multicast state
1878  *
1879  * If the BATADV_MCAST_WANT_NO_RTR4 flag of this originator, orig, has
1880  * toggled then this method updates counter and list accordingly.
1881  *
1882  * Caller needs to hold orig->mcast_handler_lock.
1883  */
1884 static void batadv_mcast_want_rtr4_update(struct batadv_priv *bat_priv,
1885                                           struct batadv_orig_node *orig,
1886                                           u8 mcast_flags)
1887 {
1888         struct hlist_node *node = &orig->mcast_want_all_rtr4_node;
1889         struct hlist_head *head = &bat_priv->mcast.want_all_rtr4_list;
1890 
1891         lockdep_assert_held(&orig->mcast_handler_lock);
1892 
1893         /* switched from flag set to unset */
1894         if (!(mcast_flags & BATADV_MCAST_WANT_NO_RTR4) &&
1895             orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR4) {
1896                 atomic_inc(&bat_priv->mcast.num_want_all_rtr4);
1897 
1898                 spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1899                 /* flag checks above + mcast_handler_lock prevents this */
1900                 WARN_ON(!hlist_unhashed(node));
1901 
1902                 hlist_add_head_rcu(node, head);
1903                 spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1904         /* switched from flag unset to set */
1905         } else if (mcast_flags & BATADV_MCAST_WANT_NO_RTR4 &&
1906                    !(orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR4)) {
1907                 atomic_dec(&bat_priv->mcast.num_want_all_rtr4);
1908 
1909                 spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1910                 /* flag checks above + mcast_handler_lock prevents this */
1911                 WARN_ON(hlist_unhashed(node));
1912 
1913                 hlist_del_init_rcu(node);
1914                 spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1915         }
1916 }
1917 
1918 /**
1919  * batadv_mcast_want_rtr6_update() - update want-all-rtr6 counter and list
1920  * @bat_priv: the bat priv with all the soft interface information
1921  * @orig: the orig_node which multicast state might have changed of
1922  * @mcast_flags: flags indicating the new multicast state
1923  *
1924  * If the BATADV_MCAST_WANT_NO_RTR6 flag of this originator, orig, has
1925  * toggled then this method updates counter and list accordingly.
1926  *
1927  * Caller needs to hold orig->mcast_handler_lock.
1928  */
1929 static void batadv_mcast_want_rtr6_update(struct batadv_priv *bat_priv,
1930                                           struct batadv_orig_node *orig,
1931                                           u8 mcast_flags)
1932 {
1933         struct hlist_node *node = &orig->mcast_want_all_rtr6_node;
1934         struct hlist_head *head = &bat_priv->mcast.want_all_rtr6_list;
1935 
1936         lockdep_assert_held(&orig->mcast_handler_lock);
1937 
1938         /* switched from flag set to unset */
1939         if (!(mcast_flags & BATADV_MCAST_WANT_NO_RTR6) &&
1940             orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR6) {
1941                 atomic_inc(&bat_priv->mcast.num_want_all_rtr6);
1942 
1943                 spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1944                 /* flag checks above + mcast_handler_lock prevents this */
1945                 WARN_ON(!hlist_unhashed(node));
1946 
1947                 hlist_add_head_rcu(node, head);
1948                 spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1949         /* switched from flag unset to set */
1950         } else if (mcast_flags & BATADV_MCAST_WANT_NO_RTR6 &&
1951                    !(orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR6)) {
1952                 atomic_dec(&bat_priv->mcast.num_want_all_rtr6);
1953 
1954                 spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1955                 /* flag checks above + mcast_handler_lock prevents this */
1956                 WARN_ON(hlist_unhashed(node));
1957 
1958                 hlist_del_init_rcu(node);
1959                 spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1960         }
1961 }
1962 
1963 /**
1964  * batadv_mcast_tvlv_flags_get() - get multicast flags from an OGM TVLV
1965  * @enabled: whether the originator has multicast TVLV support enabled
1966  * @tvlv_value: tvlv buffer containing the multicast flags
1967  * @tvlv_value_len: tvlv buffer length
1968  *
1969  * Return: multicast flags for the given tvlv buffer
1970  */
1971 static u8
1972 batadv_mcast_tvlv_flags_get(bool enabled, void *tvlv_value, u16 tvlv_value_len)
1973 {
1974         u8 mcast_flags = BATADV_NO_FLAGS;
1975 
1976         if (enabled && tvlv_value && tvlv_value_len >= sizeof(mcast_flags))
1977                 mcast_flags = *(u8 *)tvlv_value;
1978 
1979         if (!enabled) {
1980                 mcast_flags |= BATADV_MCAST_WANT_ALL_IPV4;
1981                 mcast_flags |= BATADV_MCAST_WANT_ALL_IPV6;
1982         }
1983 
1984         /* remove redundant flags to avoid sending duplicate packets later */
1985         if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV4)
1986                 mcast_flags |= BATADV_MCAST_WANT_NO_RTR4;
1987 
1988         if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV6)
1989                 mcast_flags |= BATADV_MCAST_WANT_NO_RTR6;
1990 
1991         return mcast_flags;
1992 }
1993 
1994 /**
1995  * batadv_mcast_tvlv_ogm_handler() - process incoming multicast tvlv container
1996  * @bat_priv: the bat priv with all the soft interface information
1997  * @orig: the orig_node of the ogm
1998  * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
1999  * @tvlv_value: tvlv buffer containing the multicast data
2000  * @tvlv_value_len: tvlv buffer length
2001  */
2002 static void batadv_mcast_tvlv_ogm_handler(struct batadv_priv *bat_priv,
2003                                           struct batadv_orig_node *orig,
2004                                           u8 flags,
2005                                           void *tvlv_value,
2006                                           u16 tvlv_value_len)
2007 {
2008         bool orig_mcast_enabled = !(flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
2009         u8 mcast_flags;
2010 
2011         mcast_flags = batadv_mcast_tvlv_flags_get(orig_mcast_enabled,
2012                                                   tvlv_value, tvlv_value_len);
2013 
2014         spin_lock_bh(&orig->mcast_handler_lock);
2015 
2016         if (orig_mcast_enabled &&
2017             !test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities)) {
2018                 set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities);
2019         } else if (!orig_mcast_enabled &&
2020                    test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities)) {
2021                 clear_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities);
2022         }
2023 
2024         set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capa_initialized);
2025 
2026         batadv_mcast_want_unsnoop_update(bat_priv, orig, mcast_flags);
2027         batadv_mcast_want_ipv4_update(bat_priv, orig, mcast_flags);
2028         batadv_mcast_want_ipv6_update(bat_priv, orig, mcast_flags);
2029         batadv_mcast_want_rtr4_update(bat_priv, orig, mcast_flags);
2030         batadv_mcast_want_rtr6_update(bat_priv, orig, mcast_flags);
2031 
2032         orig->mcast_flags = mcast_flags;
2033         spin_unlock_bh(&orig->mcast_handler_lock);
2034 }
2035 
2036 /**
2037  * batadv_mcast_init() - initialize the multicast optimizations structures
2038  * @bat_priv: the bat priv with all the soft interface information
2039  */
2040 void batadv_mcast_init(struct batadv_priv *bat_priv)
2041 {
2042         batadv_tvlv_handler_register(bat_priv, batadv_mcast_tvlv_ogm_handler,
2043                                      NULL, BATADV_TVLV_MCAST, 2,
2044                                      BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
2045 
2046         INIT_DELAYED_WORK(&bat_priv->mcast.work, batadv_mcast_mla_update);
2047         batadv_mcast_start_timer(bat_priv);
2048 }
2049 
2050 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
2051 /**
2052  * batadv_mcast_flags_print_header() - print own mcast flags to debugfs table
2053  * @bat_priv: the bat priv with all the soft interface information
2054  * @seq: debugfs table seq_file struct
2055  *
2056  * Prints our own multicast flags including a more specific reason why
2057  * they are set, that is prints the bridge and querier state too, to
2058  * the debugfs table specified via @seq.
2059  */
2060 static void batadv_mcast_flags_print_header(struct batadv_priv *bat_priv,
2061                                             struct seq_file *seq)
2062 {
2063         struct batadv_mcast_mla_flags *mla_flags = &bat_priv->mcast.mla_flags;
2064         char querier4, querier6, shadowing4, shadowing6;
2065         bool bridged = mla_flags->bridged;
2066         u8 flags = mla_flags->tvlv_flags;
2067 
2068         if (bridged) {
2069                 querier4 = mla_flags->querier_ipv4.exists ? '.' : '4';
2070                 querier6 = mla_flags->querier_ipv6.exists ? '.' : '6';
2071                 shadowing4 = mla_flags->querier_ipv4.shadowing ? '4' : '.';
2072                 shadowing6 = mla_flags->querier_ipv6.shadowing ? '6' : '.';
2073         } else {
2074                 querier4 = '?';
2075                 querier6 = '?';
2076                 shadowing4 = '?';
2077                 shadowing6 = '?';
2078         }
2079 
2080         seq_printf(seq, "Multicast flags (own flags: [%c%c%c%s%s])\n",
2081                    (flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) ? 'U' : '.',
2082                    (flags & BATADV_MCAST_WANT_ALL_IPV4) ? '4' : '.',
2083                    (flags & BATADV_MCAST_WANT_ALL_IPV6) ? '6' : '.',
2084                    !(flags & BATADV_MCAST_WANT_NO_RTR4) ? "R4" : ". ",
2085                    !(flags & BATADV_MCAST_WANT_NO_RTR6) ? "R6" : ". ");
2086         seq_printf(seq, "* Bridged [U]\t\t\t\t%c\n", bridged ? 'U' : '.');
2087         seq_printf(seq, "* No IGMP/MLD Querier [4/6]:\t\t%c/%c\n",
2088                    querier4, querier6);
2089         seq_printf(seq, "* Shadowing IGMP/MLD Querier [4/6]:\t%c/%c\n",
2090                    shadowing4, shadowing6);
2091         seq_puts(seq, "-------------------------------------------\n");
2092         seq_printf(seq, "       %-10s %s\n", "Originator", "Flags");
2093 }
2094 
2095 /**
2096  * batadv_mcast_flags_seq_print_text() - print the mcast flags of other nodes
2097  * @seq: seq file to print on
2098  * @offset: not used
2099  *
2100  * This prints a table of (primary) originators and their according
2101  * multicast flags, including (in the header) our own.
2102  *
2103  * Return: always 0
2104  */
2105 int batadv_mcast_flags_seq_print_text(struct seq_file *seq, void *offset)
2106 {
2107         struct net_device *net_dev = (struct net_device *)seq->private;
2108         struct batadv_priv *bat_priv = netdev_priv(net_dev);
2109         struct batadv_hard_iface *primary_if;
2110         struct batadv_hashtable *hash = bat_priv->orig_hash;
2111         struct batadv_orig_node *orig_node;
2112         struct hlist_head *head;
2113         u8 flags;
2114         u32 i;
2115 
2116         primary_if = batadv_seq_print_text_primary_if_get(seq);
2117         if (!primary_if)
2118                 return 0;
2119 
2120         batadv_mcast_flags_print_header(bat_priv, seq);
2121 
2122         for (i = 0; i < hash->size; i++) {
2123                 head = &hash->table[i];
2124 
2125                 rcu_read_lock();
2126                 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
2127                         if (!test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
2128                                       &orig_node->capa_initialized))
2129                                 continue;
2130 
2131                         if (!test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
2132                                       &orig_node->capabilities)) {
2133                                 seq_printf(seq, "%pM -\n", orig_node->orig);
2134                                 continue;
2135                         }
2136 
2137                         flags = orig_node->mcast_flags;
2138 
2139                         seq_printf(seq, "%pM [%c%c%c%s%s]\n", orig_node->orig,
2140                                    (flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES)
2141                                    ? 'U' : '.',
2142                                    (flags & BATADV_MCAST_WANT_ALL_IPV4)
2143                                    ? '4' : '.',
2144                                    (flags & BATADV_MCAST_WANT_ALL_IPV6)
2145                                    ? '6' : '.',
2146                                    !(flags & BATADV_MCAST_WANT_NO_RTR4)
2147                                    ? "R4" : ". ",
2148                                    !(flags & BATADV_MCAST_WANT_NO_RTR6)
2149                                    ? "R6" : ". ");
2150                 }
2151                 rcu_read_unlock();
2152         }
2153 
2154         batadv_hardif_put(primary_if);
2155 
2156         return 0;
2157 }
2158 #endif
2159 
2160 /**
2161  * batadv_mcast_mesh_info_put() - put multicast info into a netlink message
2162  * @msg: buffer for the message
2163  * @bat_priv: the bat priv with all the soft interface information
2164  *
2165  * Return: 0 or error code.
2166  */
2167 int batadv_mcast_mesh_info_put(struct sk_buff *msg,
2168                                struct batadv_priv *bat_priv)
2169 {
2170         u32 flags = bat_priv->mcast.mla_flags.tvlv_flags;
2171         u32 flags_priv = BATADV_NO_FLAGS;
2172 
2173         if (bat_priv->mcast.mla_flags.bridged) {
2174                 flags_priv |= BATADV_MCAST_FLAGS_BRIDGED;
2175 
2176                 if (bat_priv->mcast.mla_flags.querier_ipv4.exists)
2177                         flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV4_EXISTS;
2178                 if (bat_priv->mcast.mla_flags.querier_ipv6.exists)
2179                         flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV6_EXISTS;
2180                 if (bat_priv->mcast.mla_flags.querier_ipv4.shadowing)
2181                         flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV4_SHADOWING;
2182                 if (bat_priv->mcast.mla_flags.querier_ipv6.shadowing)
2183                         flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV6_SHADOWING;
2184         }
2185 
2186         if (nla_put_u32(msg, BATADV_ATTR_MCAST_FLAGS, flags) ||
2187             nla_put_u32(msg, BATADV_ATTR_MCAST_FLAGS_PRIV, flags_priv))
2188                 return -EMSGSIZE;
2189 
2190         return 0;
2191 }
2192 
2193 /**
2194  * batadv_mcast_flags_dump_entry() - dump one entry of the multicast flags table
2195  *  to a netlink socket
2196  * @msg: buffer for the message
2197  * @portid: netlink port
2198  * @cb: Control block containing additional options
2199  * @orig_node: originator to dump the multicast flags of
2200  *
2201  * Return: 0 or error code.
2202  */
2203 static int
2204 batadv_mcast_flags_dump_entry(struct sk_buff *msg, u32 portid,
2205                               struct netlink_callback *cb,
2206                               struct batadv_orig_node *orig_node)
2207 {
2208         void *hdr;
2209 
2210         hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
2211                           &batadv_netlink_family, NLM_F_MULTI,
2212                           BATADV_CMD_GET_MCAST_FLAGS);
2213         if (!hdr)
2214                 return -ENOBUFS;
2215 
2216         genl_dump_check_consistent(cb, hdr);
2217 
2218         if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
2219                     orig_node->orig)) {
2220                 genlmsg_cancel(msg, hdr);
2221                 return -EMSGSIZE;
2222         }
2223 
2224         if (test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
2225                      &orig_node->capabilities)) {
2226                 if (nla_put_u32(msg, BATADV_ATTR_MCAST_FLAGS,
2227                                 orig_node->mcast_flags)) {
2228                         genlmsg_cancel(msg, hdr);
2229                         return -EMSGSIZE;
2230                 }
2231         }
2232 
2233         genlmsg_end(msg, hdr);
2234         return 0;
2235 }
2236 
2237 /**
2238  * batadv_mcast_flags_dump_bucket() - dump one bucket of the multicast flags
2239  *  table to a netlink socket
2240  * @msg: buffer for the message
2241  * @portid: netlink port
2242  * @cb: Control block containing additional options
2243  * @hash: hash to dump
2244  * @bucket: bucket index to dump
2245  * @idx_skip: How many entries to skip
2246  *
2247  * Return: 0 or error code.
2248  */
2249 static int
2250 batadv_mcast_flags_dump_bucket(struct sk_buff *msg, u32 portid,
2251                                struct netlink_callback *cb,
2252                                struct batadv_hashtable *hash,
2253                                unsigned int bucket, long *idx_skip)
2254 {
2255         struct batadv_orig_node *orig_node;
2256         long idx = 0;
2257 
2258         spin_lock_bh(&hash->list_locks[bucket]);
2259         cb->seq = atomic_read(&hash->generation) << 1 | 1;
2260 
2261         hlist_for_each_entry(orig_node, &hash->table[bucket], hash_entry) {
2262                 if (!test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
2263                               &orig_node->capa_initialized))
2264                         continue;
2265 
2266                 if (idx < *idx_skip)
2267                         goto skip;
2268 
2269                 if (batadv_mcast_flags_dump_entry(msg, portid, cb, orig_node)) {
2270                         spin_unlock_bh(&hash->list_locks[bucket]);
2271                         *idx_skip = idx;
2272 
2273                         return -EMSGSIZE;
2274                 }
2275 
2276 skip:
2277                 idx++;
2278         }
2279         spin_unlock_bh(&hash->list_locks[bucket]);
2280 
2281         return 0;
2282 }
2283 
2284 /**
2285  * __batadv_mcast_flags_dump() - dump multicast flags table to a netlink socket
2286  * @msg: buffer for the message
2287  * @portid: netlink port
2288  * @cb: Control block containing additional options
2289  * @bat_priv: the bat priv with all the soft interface information
2290  * @bucket: current bucket to dump
2291  * @idx: index in current bucket to the next entry to dump
2292  *
2293  * Return: 0 or error code.
2294  */
2295 static int
2296 __batadv_mcast_flags_dump(struct sk_buff *msg, u32 portid,
2297                           struct netlink_callback *cb,
2298                           struct batadv_priv *bat_priv, long *bucket, long *idx)
2299 {
2300         struct batadv_hashtable *hash = bat_priv->orig_hash;
2301         long bucket_tmp = *bucket;
2302         long idx_tmp = *idx;
2303 
2304         while (bucket_tmp < hash->size) {
2305                 if (batadv_mcast_flags_dump_bucket(msg, portid, cb, hash,
2306                                                    bucket_tmp, &idx_tmp))
2307                         break;
2308 
2309                 bucket_tmp++;
2310                 idx_tmp = 0;
2311         }
2312 
2313         *bucket = bucket_tmp;
2314         *idx = idx_tmp;
2315 
2316         return msg->len;
2317 }
2318 
2319 /**
2320  * batadv_mcast_netlink_get_primary() - get primary interface from netlink
2321  *  callback
2322  * @cb: netlink callback structure
2323  * @primary_if: the primary interface pointer to return the result in
2324  *
2325  * Return: 0 or error code.
2326  */
2327 static int
2328 batadv_mcast_netlink_get_primary(struct netlink_callback *cb,
2329                                  struct batadv_hard_iface **primary_if)
2330 {
2331         struct batadv_hard_iface *hard_iface = NULL;
2332         struct net *net = sock_net(cb->skb->sk);
2333         struct net_device *soft_iface;
2334         struct batadv_priv *bat_priv;
2335         int ifindex;
2336         int ret = 0;
2337 
2338         ifindex = batadv_netlink_get_ifindex(cb->nlh, BATADV_ATTR_MESH_IFINDEX);
2339         if (!ifindex)
2340                 return -EINVAL;
2341 
2342         soft_iface = dev_get_by_index(net, ifindex);
2343         if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
2344                 ret = -ENODEV;
2345                 goto out;
2346         }
2347 
2348         bat_priv = netdev_priv(soft_iface);
2349 
2350         hard_iface = batadv_primary_if_get_selected(bat_priv);
2351         if (!hard_iface || hard_iface->if_status != BATADV_IF_ACTIVE) {
2352                 ret = -ENOENT;
2353                 goto out;
2354         }
2355 
2356 out:
2357         if (soft_iface)
2358                 dev_put(soft_iface);
2359 
2360         if (!ret && primary_if)
2361                 *primary_if = hard_iface;
2362         else if (hard_iface)
2363                 batadv_hardif_put(hard_iface);
2364 
2365         return ret;
2366 }
2367 
2368 /**
2369  * batadv_mcast_flags_dump() - dump multicast flags table to a netlink socket
2370  * @msg: buffer for the message
2371  * @cb: callback structure containing arguments
2372  *
2373  * Return: message length.
2374  */
2375 int batadv_mcast_flags_dump(struct sk_buff *msg, struct netlink_callback *cb)
2376 {
2377         struct batadv_hard_iface *primary_if = NULL;
2378         int portid = NETLINK_CB(cb->skb).portid;
2379         struct batadv_priv *bat_priv;
2380         long *bucket = &cb->args[0];
2381         long *idx = &cb->args[1];
2382         int ret;
2383 
2384         ret = batadv_mcast_netlink_get_primary(cb, &primary_if);
2385         if (ret)
2386                 return ret;
2387 
2388         bat_priv = netdev_priv(primary_if->soft_iface);
2389         ret = __batadv_mcast_flags_dump(msg, portid, cb, bat_priv, bucket, idx);
2390 
2391         batadv_hardif_put(primary_if);
2392         return ret;
2393 }
2394 
2395 /**
2396  * batadv_mcast_free() - free the multicast optimizations structures
2397  * @bat_priv: the bat priv with all the soft interface information
2398  */
2399 void batadv_mcast_free(struct batadv_priv *bat_priv)
2400 {
2401         cancel_delayed_work_sync(&bat_priv->mcast.work);
2402 
2403         batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_MCAST, 2);
2404         batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_MCAST, 2);
2405 
2406         /* safely calling outside of worker, as worker was canceled above */
2407         batadv_mcast_mla_tt_retract(bat_priv, NULL);
2408 }
2409 
2410 /**
2411  * batadv_mcast_purge_orig() - reset originator global mcast state modifications
2412  * @orig: the originator which is going to get purged
2413  */
2414 void batadv_mcast_purge_orig(struct batadv_orig_node *orig)
2415 {
2416         struct batadv_priv *bat_priv = orig->bat_priv;
2417 
2418         spin_lock_bh(&orig->mcast_handler_lock);
2419 
2420         batadv_mcast_want_unsnoop_update(bat_priv, orig, BATADV_NO_FLAGS);
2421         batadv_mcast_want_ipv4_update(bat_priv, orig, BATADV_NO_FLAGS);
2422         batadv_mcast_want_ipv6_update(bat_priv, orig, BATADV_NO_FLAGS);
2423         batadv_mcast_want_rtr4_update(bat_priv, orig,
2424                                       BATADV_MCAST_WANT_NO_RTR4);
2425         batadv_mcast_want_rtr6_update(bat_priv, orig,
2426                                       BATADV_MCAST_WANT_NO_RTR6);
2427 
2428         spin_unlock_bh(&orig->mcast_handler_lock);
2429 }