xref: /linux/net/batman-adv/multicast.c (revision f3a8b6645dc2e60d11f20c1c23afd964ff4e55ae)
1 /* Copyright (C) 2014-2016  B.A.T.M.A.N. contributors:
2  *
3  * Linus Lüssing
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of version 2 of the GNU General Public
7  * License as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, see <http://www.gnu.org/licenses/>.
16  */
17 
18 #include "multicast.h"
19 #include "main.h"
20 
21 #include <linux/atomic.h>
22 #include <linux/bitops.h>
23 #include <linux/bug.h>
24 #include <linux/byteorder/generic.h>
25 #include <linux/errno.h>
26 #include <linux/etherdevice.h>
27 #include <linux/fs.h>
28 #include <linux/icmpv6.h>
29 #include <linux/if_bridge.h>
30 #include <linux/if_ether.h>
31 #include <linux/igmp.h>
32 #include <linux/in.h>
33 #include <linux/in6.h>
34 #include <linux/ip.h>
35 #include <linux/ipv6.h>
36 #include <linux/kernel.h>
37 #include <linux/kref.h>
38 #include <linux/list.h>
39 #include <linux/lockdep.h>
40 #include <linux/netdevice.h>
41 #include <linux/printk.h>
42 #include <linux/rculist.h>
43 #include <linux/rcupdate.h>
44 #include <linux/seq_file.h>
45 #include <linux/skbuff.h>
46 #include <linux/slab.h>
47 #include <linux/spinlock.h>
48 #include <linux/stddef.h>
49 #include <linux/string.h>
50 #include <linux/types.h>
51 #include <net/addrconf.h>
52 #include <net/if_inet6.h>
53 #include <net/ip.h>
54 #include <net/ipv6.h>
55 
56 #include "hard-interface.h"
57 #include "hash.h"
58 #include "log.h"
59 #include "packet.h"
60 #include "translation-table.h"
61 #include "tvlv.h"
62 
63 /**
64  * batadv_mcast_get_bridge - get the bridge on top of the softif if it exists
65  * @soft_iface: netdev struct of the mesh interface
66  *
67  * If the given soft interface has a bridge on top then the refcount
68  * of the according net device is increased.
69  *
70  * Return: NULL if no such bridge exists. Otherwise the net device of the
71  * bridge.
72  */
73 static struct net_device *batadv_mcast_get_bridge(struct net_device *soft_iface)
74 {
75 	struct net_device *upper = soft_iface;
76 
77 	rcu_read_lock();
78 	do {
79 		upper = netdev_master_upper_dev_get_rcu(upper);
80 	} while (upper && !(upper->priv_flags & IFF_EBRIDGE));
81 
82 	if (upper)
83 		dev_hold(upper);
84 	rcu_read_unlock();
85 
86 	return upper;
87 }
88 
89 /**
90  * batadv_mcast_mla_softif_get - get softif multicast listeners
91  * @dev: the device to collect multicast addresses from
92  * @mcast_list: a list to put found addresses into
93  *
94  * Collects multicast addresses of multicast listeners residing
95  * on this kernel on the given soft interface, dev, in
96  * the given mcast_list. In general, multicast listeners provided by
97  * your multicast receiving applications run directly on this node.
98  *
99  * If there is a bridge interface on top of dev, collects from that one
100  * instead. Just like with IP addresses and routes, multicast listeners
101  * will(/should) register to the bridge interface instead of an
102  * enslaved bat0.
103  *
104  * Return: -ENOMEM on memory allocation error or the number of
105  * items added to the mcast_list otherwise.
106  */
107 static int batadv_mcast_mla_softif_get(struct net_device *dev,
108 				       struct hlist_head *mcast_list)
109 {
110 	struct net_device *bridge = batadv_mcast_get_bridge(dev);
111 	struct netdev_hw_addr *mc_list_entry;
112 	struct batadv_hw_addr *new;
113 	int ret = 0;
114 
115 	netif_addr_lock_bh(bridge ? bridge : dev);
116 	netdev_for_each_mc_addr(mc_list_entry, bridge ? bridge : dev) {
117 		new = kmalloc(sizeof(*new), GFP_ATOMIC);
118 		if (!new) {
119 			ret = -ENOMEM;
120 			break;
121 		}
122 
123 		ether_addr_copy(new->addr, mc_list_entry->addr);
124 		hlist_add_head(&new->list, mcast_list);
125 		ret++;
126 	}
127 	netif_addr_unlock_bh(bridge ? bridge : dev);
128 
129 	if (bridge)
130 		dev_put(bridge);
131 
132 	return ret;
133 }
134 
135 /**
136  * batadv_mcast_mla_is_duplicate - check whether an address is in a list
137  * @mcast_addr: the multicast address to check
138  * @mcast_list: the list with multicast addresses to search in
139  *
140  * Return: true if the given address is already in the given list.
141  * Otherwise returns false.
142  */
143 static bool batadv_mcast_mla_is_duplicate(u8 *mcast_addr,
144 					  struct hlist_head *mcast_list)
145 {
146 	struct batadv_hw_addr *mcast_entry;
147 
148 	hlist_for_each_entry(mcast_entry, mcast_list, list)
149 		if (batadv_compare_eth(mcast_entry->addr, mcast_addr))
150 			return true;
151 
152 	return false;
153 }
154 
155 /**
156  * batadv_mcast_mla_br_addr_cpy - copy a bridge multicast address
157  * @dst: destination to write to - a multicast MAC address
158  * @src: source to read from - a multicast IP address
159  *
160  * Converts a given multicast IPv4/IPv6 address from a bridge
161  * to its matching multicast MAC address and copies it into the given
162  * destination buffer.
163  *
164  * Caller needs to make sure the destination buffer can hold
165  * at least ETH_ALEN bytes.
166  */
167 static void batadv_mcast_mla_br_addr_cpy(char *dst, const struct br_ip *src)
168 {
169 	if (src->proto == htons(ETH_P_IP))
170 		ip_eth_mc_map(src->u.ip4, dst);
171 #if IS_ENABLED(CONFIG_IPV6)
172 	else if (src->proto == htons(ETH_P_IPV6))
173 		ipv6_eth_mc_map(&src->u.ip6, dst);
174 #endif
175 	else
176 		eth_zero_addr(dst);
177 }
178 
179 /**
180  * batadv_mcast_mla_bridge_get - get bridged-in multicast listeners
181  * @dev: a bridge slave whose bridge to collect multicast addresses from
182  * @mcast_list: a list to put found addresses into
183  *
184  * Collects multicast addresses of multicast listeners residing
185  * on foreign, non-mesh devices which we gave access to our mesh via
186  * a bridge on top of the given soft interface, dev, in the given
187  * mcast_list.
188  *
189  * Return: -ENOMEM on memory allocation error or the number of
190  * items added to the mcast_list otherwise.
191  */
192 static int batadv_mcast_mla_bridge_get(struct net_device *dev,
193 				       struct hlist_head *mcast_list)
194 {
195 	struct list_head bridge_mcast_list = LIST_HEAD_INIT(bridge_mcast_list);
196 	struct br_ip_list *br_ip_entry, *tmp;
197 	struct batadv_hw_addr *new;
198 	u8 mcast_addr[ETH_ALEN];
199 	int ret;
200 
201 	/* we don't need to detect these devices/listeners, the IGMP/MLD
202 	 * snooping code of the Linux bridge already does that for us
203 	 */
204 	ret = br_multicast_list_adjacent(dev, &bridge_mcast_list);
205 	if (ret < 0)
206 		goto out;
207 
208 	list_for_each_entry(br_ip_entry, &bridge_mcast_list, list) {
209 		batadv_mcast_mla_br_addr_cpy(mcast_addr, &br_ip_entry->addr);
210 		if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
211 			continue;
212 
213 		new = kmalloc(sizeof(*new), GFP_ATOMIC);
214 		if (!new) {
215 			ret = -ENOMEM;
216 			break;
217 		}
218 
219 		ether_addr_copy(new->addr, mcast_addr);
220 		hlist_add_head(&new->list, mcast_list);
221 	}
222 
223 out:
224 	list_for_each_entry_safe(br_ip_entry, tmp, &bridge_mcast_list, list) {
225 		list_del(&br_ip_entry->list);
226 		kfree(br_ip_entry);
227 	}
228 
229 	return ret;
230 }
231 
232 /**
233  * batadv_mcast_mla_list_free - free a list of multicast addresses
234  * @bat_priv: the bat priv with all the soft interface information
235  * @mcast_list: the list to free
236  *
237  * Removes and frees all items in the given mcast_list.
238  */
239 static void batadv_mcast_mla_list_free(struct batadv_priv *bat_priv,
240 				       struct hlist_head *mcast_list)
241 {
242 	struct batadv_hw_addr *mcast_entry;
243 	struct hlist_node *tmp;
244 
245 	lockdep_assert_held(&bat_priv->tt.commit_lock);
246 
247 	hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) {
248 		hlist_del(&mcast_entry->list);
249 		kfree(mcast_entry);
250 	}
251 }
252 
253 /**
254  * batadv_mcast_mla_tt_retract - clean up multicast listener announcements
255  * @bat_priv: the bat priv with all the soft interface information
256  * @mcast_list: a list of addresses which should _not_ be removed
257  *
258  * Retracts the announcement of any multicast listener from the
259  * translation table except the ones listed in the given mcast_list.
260  *
261  * If mcast_list is NULL then all are retracted.
262  */
263 static void batadv_mcast_mla_tt_retract(struct batadv_priv *bat_priv,
264 					struct hlist_head *mcast_list)
265 {
266 	struct batadv_hw_addr *mcast_entry;
267 	struct hlist_node *tmp;
268 
269 	lockdep_assert_held(&bat_priv->tt.commit_lock);
270 
271 	hlist_for_each_entry_safe(mcast_entry, tmp, &bat_priv->mcast.mla_list,
272 				  list) {
273 		if (mcast_list &&
274 		    batadv_mcast_mla_is_duplicate(mcast_entry->addr,
275 						  mcast_list))
276 			continue;
277 
278 		batadv_tt_local_remove(bat_priv, mcast_entry->addr,
279 				       BATADV_NO_FLAGS,
280 				       "mcast TT outdated", false);
281 
282 		hlist_del(&mcast_entry->list);
283 		kfree(mcast_entry);
284 	}
285 }
286 
287 /**
288  * batadv_mcast_mla_tt_add - add multicast listener announcements
289  * @bat_priv: the bat priv with all the soft interface information
290  * @mcast_list: a list of addresses which are going to get added
291  *
292  * Adds multicast listener announcements from the given mcast_list to the
293  * translation table if they have not been added yet.
294  */
295 static void batadv_mcast_mla_tt_add(struct batadv_priv *bat_priv,
296 				    struct hlist_head *mcast_list)
297 {
298 	struct batadv_hw_addr *mcast_entry;
299 	struct hlist_node *tmp;
300 
301 	lockdep_assert_held(&bat_priv->tt.commit_lock);
302 
303 	if (!mcast_list)
304 		return;
305 
306 	hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) {
307 		if (batadv_mcast_mla_is_duplicate(mcast_entry->addr,
308 						  &bat_priv->mcast.mla_list))
309 			continue;
310 
311 		if (!batadv_tt_local_add(bat_priv->soft_iface,
312 					 mcast_entry->addr, BATADV_NO_FLAGS,
313 					 BATADV_NULL_IFINDEX, BATADV_NO_MARK))
314 			continue;
315 
316 		hlist_del(&mcast_entry->list);
317 		hlist_add_head(&mcast_entry->list, &bat_priv->mcast.mla_list);
318 	}
319 }
320 
321 /**
322  * batadv_mcast_has_bridge - check whether the soft-iface is bridged
323  * @bat_priv: the bat priv with all the soft interface information
324  *
325  * Checks whether there is a bridge on top of our soft interface.
326  *
327  * Return: true if there is a bridge, false otherwise.
328  */
329 static bool batadv_mcast_has_bridge(struct batadv_priv *bat_priv)
330 {
331 	struct net_device *upper = bat_priv->soft_iface;
332 
333 	rcu_read_lock();
334 	do {
335 		upper = netdev_master_upper_dev_get_rcu(upper);
336 	} while (upper && !(upper->priv_flags & IFF_EBRIDGE));
337 	rcu_read_unlock();
338 
339 	return upper;
340 }
341 
342 /**
343  * batadv_mcast_querier_log - debug output regarding the querier status on link
344  * @bat_priv: the bat priv with all the soft interface information
345  * @str_proto: a string for the querier protocol (e.g. "IGMP" or "MLD")
346  * @old_state: the previous querier state on our link
347  * @new_state: the new querier state on our link
348  *
349  * Outputs debug messages to the logging facility with log level 'mcast'
350  * regarding changes to the querier status on the link which are relevant
351  * to our multicast optimizations.
352  *
353  * Usually this is about whether a querier appeared or vanished in
354  * our mesh or whether the querier is in the suboptimal position of being
355  * behind our local bridge segment: Snooping switches will directly
356  * forward listener reports to the querier, therefore batman-adv and
357  * the bridge will potentially not see these listeners - the querier is
358  * potentially shadowing listeners from us then.
359  *
360  * This is only interesting for nodes with a bridge on top of their
361  * soft interface.
362  */
363 static void
364 batadv_mcast_querier_log(struct batadv_priv *bat_priv, char *str_proto,
365 			 struct batadv_mcast_querier_state *old_state,
366 			 struct batadv_mcast_querier_state *new_state)
367 {
368 	if (!old_state->exists && new_state->exists)
369 		batadv_info(bat_priv->soft_iface, "%s Querier appeared\n",
370 			    str_proto);
371 	else if (old_state->exists && !new_state->exists)
372 		batadv_info(bat_priv->soft_iface,
373 			    "%s Querier disappeared - multicast optimizations disabled\n",
374 			    str_proto);
375 	else if (!bat_priv->mcast.bridged && !new_state->exists)
376 		batadv_info(bat_priv->soft_iface,
377 			    "No %s Querier present - multicast optimizations disabled\n",
378 			    str_proto);
379 
380 	if (new_state->exists) {
381 		if ((!old_state->shadowing && new_state->shadowing) ||
382 		    (!old_state->exists && new_state->shadowing))
383 			batadv_dbg(BATADV_DBG_MCAST, bat_priv,
384 				   "%s Querier is behind our bridged segment: Might shadow listeners\n",
385 				   str_proto);
386 		else if (old_state->shadowing && !new_state->shadowing)
387 			batadv_dbg(BATADV_DBG_MCAST, bat_priv,
388 				   "%s Querier is not behind our bridged segment\n",
389 				   str_proto);
390 	}
391 }
392 
393 /**
394  * batadv_mcast_bridge_log - debug output for topology changes in bridged setups
395  * @bat_priv: the bat priv with all the soft interface information
396  * @bridged: a flag about whether the soft interface is currently bridged or not
397  * @querier_ipv4: (maybe) new status of a potential, selected IGMP querier
398  * @querier_ipv6: (maybe) new status of a potential, selected MLD querier
399  *
400  * If no bridges are ever used on this node, then this function does nothing.
401  *
402  * Otherwise this function outputs debug information to the 'mcast' log level
403  * which might be relevant to our multicast optimizations.
404  *
405  * More precisely, it outputs information when a bridge interface is added or
406  * removed from a soft interface. And when a bridge is present, it further
407  * outputs information about the querier state which is relevant for the
408  * multicast flags this node is going to set.
409  */
410 static void
411 batadv_mcast_bridge_log(struct batadv_priv *bat_priv, bool bridged,
412 			struct batadv_mcast_querier_state *querier_ipv4,
413 			struct batadv_mcast_querier_state *querier_ipv6)
414 {
415 	if (!bat_priv->mcast.bridged && bridged)
416 		batadv_dbg(BATADV_DBG_MCAST, bat_priv,
417 			   "Bridge added: Setting Unsnoopables(U)-flag\n");
418 	else if (bat_priv->mcast.bridged && !bridged)
419 		batadv_dbg(BATADV_DBG_MCAST, bat_priv,
420 			   "Bridge removed: Unsetting Unsnoopables(U)-flag\n");
421 
422 	if (bridged) {
423 		batadv_mcast_querier_log(bat_priv, "IGMP",
424 					 &bat_priv->mcast.querier_ipv4,
425 					 querier_ipv4);
426 		batadv_mcast_querier_log(bat_priv, "MLD",
427 					 &bat_priv->mcast.querier_ipv6,
428 					 querier_ipv6);
429 	}
430 }
431 
432 /**
433  * batadv_mcast_flags_logs - output debug information about mcast flag changes
434  * @bat_priv: the bat priv with all the soft interface information
435  * @flags: flags indicating the new multicast state
436  *
437  * Whenever the multicast flags this nodes announces changes (@mcast_flags vs.
438  * bat_priv->mcast.flags), this notifies userspace via the 'mcast' log level.
439  */
440 static void batadv_mcast_flags_log(struct batadv_priv *bat_priv, u8 flags)
441 {
442 	u8 old_flags = bat_priv->mcast.flags;
443 	char str_old_flags[] = "[...]";
444 
445 	sprintf(str_old_flags, "[%c%c%c]",
446 		(old_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) ? 'U' : '.',
447 		(old_flags & BATADV_MCAST_WANT_ALL_IPV4) ? '4' : '.',
448 		(old_flags & BATADV_MCAST_WANT_ALL_IPV6) ? '6' : '.');
449 
450 	batadv_dbg(BATADV_DBG_MCAST, bat_priv,
451 		   "Changing multicast flags from '%s' to '[%c%c%c]'\n",
452 		   bat_priv->mcast.enabled ? str_old_flags : "<undefined>",
453 		   (flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) ? 'U' : '.',
454 		   (flags & BATADV_MCAST_WANT_ALL_IPV4) ? '4' : '.',
455 		   (flags & BATADV_MCAST_WANT_ALL_IPV6) ? '6' : '.');
456 }
457 
458 /**
459  * batadv_mcast_mla_tvlv_update - update multicast tvlv
460  * @bat_priv: the bat priv with all the soft interface information
461  *
462  * Updates the own multicast tvlv with our current multicast related settings,
463  * capabilities and inabilities.
464  *
465  * Return: false if we want all IPv4 && IPv6 multicast traffic and true
466  * otherwise.
467  */
468 static bool batadv_mcast_mla_tvlv_update(struct batadv_priv *bat_priv)
469 {
470 	struct batadv_tvlv_mcast_data mcast_data;
471 	struct batadv_mcast_querier_state querier4 = {false, false};
472 	struct batadv_mcast_querier_state querier6 = {false, false};
473 	struct net_device *dev = bat_priv->soft_iface;
474 	bool bridged;
475 
476 	mcast_data.flags = BATADV_NO_FLAGS;
477 	memset(mcast_data.reserved, 0, sizeof(mcast_data.reserved));
478 
479 	bridged = batadv_mcast_has_bridge(bat_priv);
480 	if (!bridged)
481 		goto update;
482 
483 #if !IS_ENABLED(CONFIG_BRIDGE_IGMP_SNOOPING)
484 	pr_warn_once("No bridge IGMP snooping compiled - multicast optimizations disabled\n");
485 #endif
486 
487 	querier4.exists = br_multicast_has_querier_anywhere(dev, ETH_P_IP);
488 	querier4.shadowing = br_multicast_has_querier_adjacent(dev, ETH_P_IP);
489 
490 	querier6.exists = br_multicast_has_querier_anywhere(dev, ETH_P_IPV6);
491 	querier6.shadowing = br_multicast_has_querier_adjacent(dev, ETH_P_IPV6);
492 
493 	mcast_data.flags |= BATADV_MCAST_WANT_ALL_UNSNOOPABLES;
494 
495 	/* 1) If no querier exists at all, then multicast listeners on
496 	 *    our local TT clients behind the bridge will keep silent.
497 	 * 2) If the selected querier is on one of our local TT clients,
498 	 *    behind the bridge, then this querier might shadow multicast
499 	 *    listeners on our local TT clients, behind this bridge.
500 	 *
501 	 * In both cases, we will signalize other batman nodes that
502 	 * we need all multicast traffic of the according protocol.
503 	 */
504 	if (!querier4.exists || querier4.shadowing)
505 		mcast_data.flags |= BATADV_MCAST_WANT_ALL_IPV4;
506 
507 	if (!querier6.exists || querier6.shadowing)
508 		mcast_data.flags |= BATADV_MCAST_WANT_ALL_IPV6;
509 
510 update:
511 	batadv_mcast_bridge_log(bat_priv, bridged, &querier4, &querier6);
512 
513 	bat_priv->mcast.querier_ipv4.exists = querier4.exists;
514 	bat_priv->mcast.querier_ipv4.shadowing = querier4.shadowing;
515 
516 	bat_priv->mcast.querier_ipv6.exists = querier6.exists;
517 	bat_priv->mcast.querier_ipv6.shadowing = querier6.shadowing;
518 
519 	bat_priv->mcast.bridged = bridged;
520 
521 	if (!bat_priv->mcast.enabled ||
522 	    mcast_data.flags != bat_priv->mcast.flags) {
523 		batadv_mcast_flags_log(bat_priv, mcast_data.flags);
524 		batadv_tvlv_container_register(bat_priv, BATADV_TVLV_MCAST, 2,
525 					       &mcast_data, sizeof(mcast_data));
526 		bat_priv->mcast.flags = mcast_data.flags;
527 		bat_priv->mcast.enabled = true;
528 	}
529 
530 	return !(mcast_data.flags &
531 		 (BATADV_MCAST_WANT_ALL_IPV4 | BATADV_MCAST_WANT_ALL_IPV6));
532 }
533 
534 /**
535  * batadv_mcast_mla_update - update the own MLAs
536  * @bat_priv: the bat priv with all the soft interface information
537  *
538  * Updates the own multicast listener announcements in the translation
539  * table as well as the own, announced multicast tvlv container.
540  */
541 void batadv_mcast_mla_update(struct batadv_priv *bat_priv)
542 {
543 	struct net_device *soft_iface = bat_priv->soft_iface;
544 	struct hlist_head mcast_list = HLIST_HEAD_INIT;
545 	int ret;
546 
547 	if (!batadv_mcast_mla_tvlv_update(bat_priv))
548 		goto update;
549 
550 	ret = batadv_mcast_mla_softif_get(soft_iface, &mcast_list);
551 	if (ret < 0)
552 		goto out;
553 
554 	ret = batadv_mcast_mla_bridge_get(soft_iface, &mcast_list);
555 	if (ret < 0)
556 		goto out;
557 
558 update:
559 	batadv_mcast_mla_tt_retract(bat_priv, &mcast_list);
560 	batadv_mcast_mla_tt_add(bat_priv, &mcast_list);
561 
562 out:
563 	batadv_mcast_mla_list_free(bat_priv, &mcast_list);
564 }
565 
566 /**
567  * batadv_mcast_is_report_ipv4 - check for IGMP reports
568  * @skb: the ethernet frame destined for the mesh
569  *
570  * This call might reallocate skb data.
571  *
572  * Checks whether the given frame is a valid IGMP report.
573  *
574  * Return: If so then true, otherwise false.
575  */
576 static bool batadv_mcast_is_report_ipv4(struct sk_buff *skb)
577 {
578 	if (ip_mc_check_igmp(skb, NULL) < 0)
579 		return false;
580 
581 	switch (igmp_hdr(skb)->type) {
582 	case IGMP_HOST_MEMBERSHIP_REPORT:
583 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
584 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
585 		return true;
586 	}
587 
588 	return false;
589 }
590 
591 /**
592  * batadv_mcast_forw_mode_check_ipv4 - check for optimized forwarding potential
593  * @bat_priv: the bat priv with all the soft interface information
594  * @skb: the IPv4 packet to check
595  * @is_unsnoopable: stores whether the destination is snoopable
596  *
597  * Checks whether the given IPv4 packet has the potential to be forwarded with a
598  * mode more optimal than classic flooding.
599  *
600  * Return: If so then 0. Otherwise -EINVAL or -ENOMEM in case of memory
601  * allocation failure.
602  */
603 static int batadv_mcast_forw_mode_check_ipv4(struct batadv_priv *bat_priv,
604 					     struct sk_buff *skb,
605 					     bool *is_unsnoopable)
606 {
607 	struct iphdr *iphdr;
608 
609 	/* We might fail due to out-of-memory -> drop it */
610 	if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*iphdr)))
611 		return -ENOMEM;
612 
613 	if (batadv_mcast_is_report_ipv4(skb))
614 		return -EINVAL;
615 
616 	iphdr = ip_hdr(skb);
617 
618 	/* TODO: Implement Multicast Router Discovery (RFC4286),
619 	 * then allow scope > link local, too
620 	 */
621 	if (!ipv4_is_local_multicast(iphdr->daddr))
622 		return -EINVAL;
623 
624 	/* link-local multicast listeners behind a bridge are
625 	 * not snoopable (see RFC4541, section 2.1.2.2)
626 	 */
627 	*is_unsnoopable = true;
628 
629 	return 0;
630 }
631 
632 #if IS_ENABLED(CONFIG_IPV6)
633 /**
634  * batadv_mcast_is_report_ipv6 - check for MLD reports
635  * @skb: the ethernet frame destined for the mesh
636  *
637  * This call might reallocate skb data.
638  *
639  * Checks whether the given frame is a valid MLD report.
640  *
641  * Return: If so then true, otherwise false.
642  */
643 static bool batadv_mcast_is_report_ipv6(struct sk_buff *skb)
644 {
645 	if (ipv6_mc_check_mld(skb, NULL) < 0)
646 		return false;
647 
648 	switch (icmp6_hdr(skb)->icmp6_type) {
649 	case ICMPV6_MGM_REPORT:
650 	case ICMPV6_MLD2_REPORT:
651 		return true;
652 	}
653 
654 	return false;
655 }
656 
657 /**
658  * batadv_mcast_forw_mode_check_ipv6 - check for optimized forwarding potential
659  * @bat_priv: the bat priv with all the soft interface information
660  * @skb: the IPv6 packet to check
661  * @is_unsnoopable: stores whether the destination is snoopable
662  *
663  * Checks whether the given IPv6 packet has the potential to be forwarded with a
664  * mode more optimal than classic flooding.
665  *
666  * Return: If so then 0. Otherwise -EINVAL is or -ENOMEM if we are out of memory
667  */
668 static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv,
669 					     struct sk_buff *skb,
670 					     bool *is_unsnoopable)
671 {
672 	struct ipv6hdr *ip6hdr;
673 
674 	/* We might fail due to out-of-memory -> drop it */
675 	if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*ip6hdr)))
676 		return -ENOMEM;
677 
678 	if (batadv_mcast_is_report_ipv6(skb))
679 		return -EINVAL;
680 
681 	ip6hdr = ipv6_hdr(skb);
682 
683 	/* TODO: Implement Multicast Router Discovery (RFC4286),
684 	 * then allow scope > link local, too
685 	 */
686 	if (IPV6_ADDR_MC_SCOPE(&ip6hdr->daddr) != IPV6_ADDR_SCOPE_LINKLOCAL)
687 		return -EINVAL;
688 
689 	/* link-local-all-nodes multicast listeners behind a bridge are
690 	 * not snoopable (see RFC4541, section 3, paragraph 3)
691 	 */
692 	if (ipv6_addr_is_ll_all_nodes(&ip6hdr->daddr))
693 		*is_unsnoopable = true;
694 
695 	return 0;
696 }
697 #endif
698 
699 /**
700  * batadv_mcast_forw_mode_check - check for optimized forwarding potential
701  * @bat_priv: the bat priv with all the soft interface information
702  * @skb: the multicast frame to check
703  * @is_unsnoopable: stores whether the destination is snoopable
704  *
705  * Checks whether the given multicast ethernet frame has the potential to be
706  * forwarded with a mode more optimal than classic flooding.
707  *
708  * Return: If so then 0. Otherwise -EINVAL is or -ENOMEM if we are out of memory
709  */
710 static int batadv_mcast_forw_mode_check(struct batadv_priv *bat_priv,
711 					struct sk_buff *skb,
712 					bool *is_unsnoopable)
713 {
714 	struct ethhdr *ethhdr = eth_hdr(skb);
715 
716 	if (!atomic_read(&bat_priv->multicast_mode))
717 		return -EINVAL;
718 
719 	if (atomic_read(&bat_priv->mcast.num_disabled))
720 		return -EINVAL;
721 
722 	switch (ntohs(ethhdr->h_proto)) {
723 	case ETH_P_IP:
724 		return batadv_mcast_forw_mode_check_ipv4(bat_priv, skb,
725 							 is_unsnoopable);
726 #if IS_ENABLED(CONFIG_IPV6)
727 	case ETH_P_IPV6:
728 		return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb,
729 							 is_unsnoopable);
730 #endif
731 	default:
732 		return -EINVAL;
733 	}
734 }
735 
736 /**
737  * batadv_mcast_forw_want_all_ip_count - count nodes with unspecific mcast
738  *  interest
739  * @bat_priv: the bat priv with all the soft interface information
740  * @ethhdr: ethernet header of a packet
741  *
742  * Return: the number of nodes which want all IPv4 multicast traffic if the
743  * given ethhdr is from an IPv4 packet or the number of nodes which want all
744  * IPv6 traffic if it matches an IPv6 packet.
745  */
746 static int batadv_mcast_forw_want_all_ip_count(struct batadv_priv *bat_priv,
747 					       struct ethhdr *ethhdr)
748 {
749 	switch (ntohs(ethhdr->h_proto)) {
750 	case ETH_P_IP:
751 		return atomic_read(&bat_priv->mcast.num_want_all_ipv4);
752 	case ETH_P_IPV6:
753 		return atomic_read(&bat_priv->mcast.num_want_all_ipv6);
754 	default:
755 		/* we shouldn't be here... */
756 		return 0;
757 	}
758 }
759 
760 /**
761  * batadv_mcast_forw_tt_node_get - get a multicast tt node
762  * @bat_priv: the bat priv with all the soft interface information
763  * @ethhdr: the ether header containing the multicast destination
764  *
765  * Return: an orig_node matching the multicast address provided by ethhdr
766  * via a translation table lookup. This increases the returned nodes refcount.
767  */
768 static struct batadv_orig_node *
769 batadv_mcast_forw_tt_node_get(struct batadv_priv *bat_priv,
770 			      struct ethhdr *ethhdr)
771 {
772 	return batadv_transtable_search(bat_priv, ethhdr->h_source,
773 					ethhdr->h_dest, BATADV_NO_FLAGS);
774 }
775 
776 /**
777  * batadv_mcast_forw_ipv4_node_get - get a node with an ipv4 flag
778  * @bat_priv: the bat priv with all the soft interface information
779  *
780  * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_IPV4 flag set and
781  * increases its refcount.
782  */
783 static struct batadv_orig_node *
784 batadv_mcast_forw_ipv4_node_get(struct batadv_priv *bat_priv)
785 {
786 	struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
787 
788 	rcu_read_lock();
789 	hlist_for_each_entry_rcu(tmp_orig_node,
790 				 &bat_priv->mcast.want_all_ipv4_list,
791 				 mcast_want_all_ipv4_node) {
792 		if (!kref_get_unless_zero(&tmp_orig_node->refcount))
793 			continue;
794 
795 		orig_node = tmp_orig_node;
796 		break;
797 	}
798 	rcu_read_unlock();
799 
800 	return orig_node;
801 }
802 
803 /**
804  * batadv_mcast_forw_ipv6_node_get - get a node with an ipv6 flag
805  * @bat_priv: the bat priv with all the soft interface information
806  *
807  * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_IPV6 flag set
808  * and increases its refcount.
809  */
810 static struct batadv_orig_node *
811 batadv_mcast_forw_ipv6_node_get(struct batadv_priv *bat_priv)
812 {
813 	struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
814 
815 	rcu_read_lock();
816 	hlist_for_each_entry_rcu(tmp_orig_node,
817 				 &bat_priv->mcast.want_all_ipv6_list,
818 				 mcast_want_all_ipv6_node) {
819 		if (!kref_get_unless_zero(&tmp_orig_node->refcount))
820 			continue;
821 
822 		orig_node = tmp_orig_node;
823 		break;
824 	}
825 	rcu_read_unlock();
826 
827 	return orig_node;
828 }
829 
830 /**
831  * batadv_mcast_forw_ip_node_get - get a node with an ipv4/ipv6 flag
832  * @bat_priv: the bat priv with all the soft interface information
833  * @ethhdr: an ethernet header to determine the protocol family from
834  *
835  * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_IPV4 or
836  * BATADV_MCAST_WANT_ALL_IPV6 flag, depending on the provided ethhdr, set and
837  * increases its refcount.
838  */
839 static struct batadv_orig_node *
840 batadv_mcast_forw_ip_node_get(struct batadv_priv *bat_priv,
841 			      struct ethhdr *ethhdr)
842 {
843 	switch (ntohs(ethhdr->h_proto)) {
844 	case ETH_P_IP:
845 		return batadv_mcast_forw_ipv4_node_get(bat_priv);
846 	case ETH_P_IPV6:
847 		return batadv_mcast_forw_ipv6_node_get(bat_priv);
848 	default:
849 		/* we shouldn't be here... */
850 		return NULL;
851 	}
852 }
853 
854 /**
855  * batadv_mcast_forw_unsnoop_node_get - get a node with an unsnoopable flag
856  * @bat_priv: the bat priv with all the soft interface information
857  *
858  * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag
859  * set and increases its refcount.
860  */
861 static struct batadv_orig_node *
862 batadv_mcast_forw_unsnoop_node_get(struct batadv_priv *bat_priv)
863 {
864 	struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
865 
866 	rcu_read_lock();
867 	hlist_for_each_entry_rcu(tmp_orig_node,
868 				 &bat_priv->mcast.want_all_unsnoopables_list,
869 				 mcast_want_all_unsnoopables_node) {
870 		if (!kref_get_unless_zero(&tmp_orig_node->refcount))
871 			continue;
872 
873 		orig_node = tmp_orig_node;
874 		break;
875 	}
876 	rcu_read_unlock();
877 
878 	return orig_node;
879 }
880 
881 /**
882  * batadv_mcast_forw_mode - check on how to forward a multicast packet
883  * @bat_priv: the bat priv with all the soft interface information
884  * @skb: The multicast packet to check
885  * @orig: an originator to be set to forward the skb to
886  *
887  * Return: the forwarding mode as enum batadv_forw_mode and in case of
888  * BATADV_FORW_SINGLE set the orig to the single originator the skb
889  * should be forwarded to.
890  */
891 enum batadv_forw_mode
892 batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb,
893 		       struct batadv_orig_node **orig)
894 {
895 	int ret, tt_count, ip_count, unsnoop_count, total_count;
896 	bool is_unsnoopable = false;
897 	struct ethhdr *ethhdr;
898 
899 	ret = batadv_mcast_forw_mode_check(bat_priv, skb, &is_unsnoopable);
900 	if (ret == -ENOMEM)
901 		return BATADV_FORW_NONE;
902 	else if (ret < 0)
903 		return BATADV_FORW_ALL;
904 
905 	ethhdr = eth_hdr(skb);
906 
907 	tt_count = batadv_tt_global_hash_count(bat_priv, ethhdr->h_dest,
908 					       BATADV_NO_FLAGS);
909 	ip_count = batadv_mcast_forw_want_all_ip_count(bat_priv, ethhdr);
910 	unsnoop_count = !is_unsnoopable ? 0 :
911 			atomic_read(&bat_priv->mcast.num_want_all_unsnoopables);
912 
913 	total_count = tt_count + ip_count + unsnoop_count;
914 
915 	switch (total_count) {
916 	case 1:
917 		if (tt_count)
918 			*orig = batadv_mcast_forw_tt_node_get(bat_priv, ethhdr);
919 		else if (ip_count)
920 			*orig = batadv_mcast_forw_ip_node_get(bat_priv, ethhdr);
921 		else if (unsnoop_count)
922 			*orig = batadv_mcast_forw_unsnoop_node_get(bat_priv);
923 
924 		if (*orig)
925 			return BATADV_FORW_SINGLE;
926 
927 		/* fall through */
928 	case 0:
929 		return BATADV_FORW_NONE;
930 	default:
931 		return BATADV_FORW_ALL;
932 	}
933 }
934 
935 /**
936  * batadv_mcast_want_unsnoop_update - update unsnoop counter and list
937  * @bat_priv: the bat priv with all the soft interface information
938  * @orig: the orig_node which multicast state might have changed of
939  * @mcast_flags: flags indicating the new multicast state
940  *
941  * If the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag of this originator,
942  * orig, has toggled then this method updates counter and list accordingly.
943  *
944  * Caller needs to hold orig->mcast_handler_lock.
945  */
946 static void batadv_mcast_want_unsnoop_update(struct batadv_priv *bat_priv,
947 					     struct batadv_orig_node *orig,
948 					     u8 mcast_flags)
949 {
950 	struct hlist_node *node = &orig->mcast_want_all_unsnoopables_node;
951 	struct hlist_head *head = &bat_priv->mcast.want_all_unsnoopables_list;
952 
953 	lockdep_assert_held(&orig->mcast_handler_lock);
954 
955 	/* switched from flag unset to set */
956 	if (mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
957 	    !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES)) {
958 		atomic_inc(&bat_priv->mcast.num_want_all_unsnoopables);
959 
960 		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
961 		/* flag checks above + mcast_handler_lock prevents this */
962 		WARN_ON(!hlist_unhashed(node));
963 
964 		hlist_add_head_rcu(node, head);
965 		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
966 	/* switched from flag set to unset */
967 	} else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) &&
968 		   orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) {
969 		atomic_dec(&bat_priv->mcast.num_want_all_unsnoopables);
970 
971 		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
972 		/* flag checks above + mcast_handler_lock prevents this */
973 		WARN_ON(hlist_unhashed(node));
974 
975 		hlist_del_init_rcu(node);
976 		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
977 	}
978 }
979 
980 /**
981  * batadv_mcast_want_ipv4_update - update want-all-ipv4 counter and list
982  * @bat_priv: the bat priv with all the soft interface information
983  * @orig: the orig_node which multicast state might have changed of
984  * @mcast_flags: flags indicating the new multicast state
985  *
986  * If the BATADV_MCAST_WANT_ALL_IPV4 flag of this originator, orig, has
987  * toggled then this method updates counter and list accordingly.
988  *
989  * Caller needs to hold orig->mcast_handler_lock.
990  */
991 static void batadv_mcast_want_ipv4_update(struct batadv_priv *bat_priv,
992 					  struct batadv_orig_node *orig,
993 					  u8 mcast_flags)
994 {
995 	struct hlist_node *node = &orig->mcast_want_all_ipv4_node;
996 	struct hlist_head *head = &bat_priv->mcast.want_all_ipv4_list;
997 
998 	lockdep_assert_held(&orig->mcast_handler_lock);
999 
1000 	/* switched from flag unset to set */
1001 	if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV4 &&
1002 	    !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4)) {
1003 		atomic_inc(&bat_priv->mcast.num_want_all_ipv4);
1004 
1005 		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1006 		/* flag checks above + mcast_handler_lock prevents this */
1007 		WARN_ON(!hlist_unhashed(node));
1008 
1009 		hlist_add_head_rcu(node, head);
1010 		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1011 	/* switched from flag set to unset */
1012 	} else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) &&
1013 		   orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) {
1014 		atomic_dec(&bat_priv->mcast.num_want_all_ipv4);
1015 
1016 		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1017 		/* flag checks above + mcast_handler_lock prevents this */
1018 		WARN_ON(hlist_unhashed(node));
1019 
1020 		hlist_del_init_rcu(node);
1021 		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1022 	}
1023 }
1024 
1025 /**
1026  * batadv_mcast_want_ipv6_update - update want-all-ipv6 counter and list
1027  * @bat_priv: the bat priv with all the soft interface information
1028  * @orig: the orig_node which multicast state might have changed of
1029  * @mcast_flags: flags indicating the new multicast state
1030  *
1031  * If the BATADV_MCAST_WANT_ALL_IPV6 flag of this originator, orig, has
1032  * toggled then this method updates counter and list accordingly.
1033  *
1034  * Caller needs to hold orig->mcast_handler_lock.
1035  */
1036 static void batadv_mcast_want_ipv6_update(struct batadv_priv *bat_priv,
1037 					  struct batadv_orig_node *orig,
1038 					  u8 mcast_flags)
1039 {
1040 	struct hlist_node *node = &orig->mcast_want_all_ipv6_node;
1041 	struct hlist_head *head = &bat_priv->mcast.want_all_ipv6_list;
1042 
1043 	lockdep_assert_held(&orig->mcast_handler_lock);
1044 
1045 	/* switched from flag unset to set */
1046 	if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV6 &&
1047 	    !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6)) {
1048 		atomic_inc(&bat_priv->mcast.num_want_all_ipv6);
1049 
1050 		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1051 		/* flag checks above + mcast_handler_lock prevents this */
1052 		WARN_ON(!hlist_unhashed(node));
1053 
1054 		hlist_add_head_rcu(node, head);
1055 		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1056 	/* switched from flag set to unset */
1057 	} else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) &&
1058 		   orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) {
1059 		atomic_dec(&bat_priv->mcast.num_want_all_ipv6);
1060 
1061 		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1062 		/* flag checks above + mcast_handler_lock prevents this */
1063 		WARN_ON(hlist_unhashed(node));
1064 
1065 		hlist_del_init_rcu(node);
1066 		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1067 	}
1068 }
1069 
1070 /**
1071  * batadv_mcast_tvlv_ogm_handler - process incoming multicast tvlv container
1072  * @bat_priv: the bat priv with all the soft interface information
1073  * @orig: the orig_node of the ogm
1074  * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
1075  * @tvlv_value: tvlv buffer containing the multicast data
1076  * @tvlv_value_len: tvlv buffer length
1077  */
1078 static void batadv_mcast_tvlv_ogm_handler(struct batadv_priv *bat_priv,
1079 					  struct batadv_orig_node *orig,
1080 					  u8 flags,
1081 					  void *tvlv_value,
1082 					  u16 tvlv_value_len)
1083 {
1084 	bool orig_mcast_enabled = !(flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
1085 	u8 mcast_flags = BATADV_NO_FLAGS;
1086 	bool orig_initialized;
1087 
1088 	if (orig_mcast_enabled && tvlv_value &&
1089 	    (tvlv_value_len >= sizeof(mcast_flags)))
1090 		mcast_flags = *(u8 *)tvlv_value;
1091 
1092 	spin_lock_bh(&orig->mcast_handler_lock);
1093 	orig_initialized = test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
1094 				    &orig->capa_initialized);
1095 
1096 	/* If mcast support is turned on decrease the disabled mcast node
1097 	 * counter only if we had increased it for this node before. If this
1098 	 * is a completely new orig_node no need to decrease the counter.
1099 	 */
1100 	if (orig_mcast_enabled &&
1101 	    !test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities)) {
1102 		if (orig_initialized)
1103 			atomic_dec(&bat_priv->mcast.num_disabled);
1104 		set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities);
1105 	/* If mcast support is being switched off or if this is an initial
1106 	 * OGM without mcast support then increase the disabled mcast
1107 	 * node counter.
1108 	 */
1109 	} else if (!orig_mcast_enabled &&
1110 		   (test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities) ||
1111 		    !orig_initialized)) {
1112 		atomic_inc(&bat_priv->mcast.num_disabled);
1113 		clear_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities);
1114 	}
1115 
1116 	set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capa_initialized);
1117 
1118 	batadv_mcast_want_unsnoop_update(bat_priv, orig, mcast_flags);
1119 	batadv_mcast_want_ipv4_update(bat_priv, orig, mcast_flags);
1120 	batadv_mcast_want_ipv6_update(bat_priv, orig, mcast_flags);
1121 
1122 	orig->mcast_flags = mcast_flags;
1123 	spin_unlock_bh(&orig->mcast_handler_lock);
1124 }
1125 
1126 /**
1127  * batadv_mcast_init - initialize the multicast optimizations structures
1128  * @bat_priv: the bat priv with all the soft interface information
1129  */
1130 void batadv_mcast_init(struct batadv_priv *bat_priv)
1131 {
1132 	batadv_tvlv_handler_register(bat_priv, batadv_mcast_tvlv_ogm_handler,
1133 				     NULL, BATADV_TVLV_MCAST, 2,
1134 				     BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
1135 }
1136 
1137 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
1138 /**
1139  * batadv_mcast_flags_print_header - print own mcast flags to debugfs table
1140  * @bat_priv: the bat priv with all the soft interface information
1141  * @seq: debugfs table seq_file struct
1142  *
1143  * Prints our own multicast flags including a more specific reason why
1144  * they are set, that is prints the bridge and querier state too, to
1145  * the debugfs table specified via @seq.
1146  */
1147 static void batadv_mcast_flags_print_header(struct batadv_priv *bat_priv,
1148 					    struct seq_file *seq)
1149 {
1150 	u8 flags = bat_priv->mcast.flags;
1151 	char querier4, querier6, shadowing4, shadowing6;
1152 	bool bridged = bat_priv->mcast.bridged;
1153 
1154 	if (bridged) {
1155 		querier4 = bat_priv->mcast.querier_ipv4.exists ? '.' : '4';
1156 		querier6 = bat_priv->mcast.querier_ipv6.exists ? '.' : '6';
1157 		shadowing4 = bat_priv->mcast.querier_ipv4.shadowing ? '4' : '.';
1158 		shadowing6 = bat_priv->mcast.querier_ipv6.shadowing ? '6' : '.';
1159 	} else {
1160 		querier4 = '?';
1161 		querier6 = '?';
1162 		shadowing4 = '?';
1163 		shadowing6 = '?';
1164 	}
1165 
1166 	seq_printf(seq, "Multicast flags (own flags: [%c%c%c])\n",
1167 		   (flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) ? 'U' : '.',
1168 		   (flags & BATADV_MCAST_WANT_ALL_IPV4) ? '4' : '.',
1169 		   (flags & BATADV_MCAST_WANT_ALL_IPV6) ? '6' : '.');
1170 	seq_printf(seq, "* Bridged [U]\t\t\t\t%c\n", bridged ? 'U' : '.');
1171 	seq_printf(seq, "* No IGMP/MLD Querier [4/6]:\t\t%c/%c\n",
1172 		   querier4, querier6);
1173 	seq_printf(seq, "* Shadowing IGMP/MLD Querier [4/6]:\t%c/%c\n",
1174 		   shadowing4, shadowing6);
1175 	seq_puts(seq, "-------------------------------------------\n");
1176 	seq_printf(seq, "       %-10s %s\n", "Originator", "Flags");
1177 }
1178 
1179 /**
1180  * batadv_mcast_flags_seq_print_text - print the mcast flags of other nodes
1181  * @seq: seq file to print on
1182  * @offset: not used
1183  *
1184  * This prints a table of (primary) originators and their according
1185  * multicast flags, including (in the header) our own.
1186  *
1187  * Return: always 0
1188  */
1189 int batadv_mcast_flags_seq_print_text(struct seq_file *seq, void *offset)
1190 {
1191 	struct net_device *net_dev = (struct net_device *)seq->private;
1192 	struct batadv_priv *bat_priv = netdev_priv(net_dev);
1193 	struct batadv_hard_iface *primary_if;
1194 	struct batadv_hashtable *hash = bat_priv->orig_hash;
1195 	struct batadv_orig_node *orig_node;
1196 	struct hlist_head *head;
1197 	u8 flags;
1198 	u32 i;
1199 
1200 	primary_if = batadv_seq_print_text_primary_if_get(seq);
1201 	if (!primary_if)
1202 		return 0;
1203 
1204 	batadv_mcast_flags_print_header(bat_priv, seq);
1205 
1206 	for (i = 0; i < hash->size; i++) {
1207 		head = &hash->table[i];
1208 
1209 		rcu_read_lock();
1210 		hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
1211 			if (!test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
1212 				      &orig_node->capa_initialized))
1213 				continue;
1214 
1215 			if (!test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
1216 				      &orig_node->capabilities)) {
1217 				seq_printf(seq, "%pM -\n", orig_node->orig);
1218 				continue;
1219 			}
1220 
1221 			flags = orig_node->mcast_flags;
1222 
1223 			seq_printf(seq, "%pM [%c%c%c]\n", orig_node->orig,
1224 				   (flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES)
1225 				   ? 'U' : '.',
1226 				   (flags & BATADV_MCAST_WANT_ALL_IPV4)
1227 				   ? '4' : '.',
1228 				   (flags & BATADV_MCAST_WANT_ALL_IPV6)
1229 				   ? '6' : '.');
1230 		}
1231 		rcu_read_unlock();
1232 	}
1233 
1234 	batadv_hardif_put(primary_if);
1235 
1236 	return 0;
1237 }
1238 #endif
1239 
1240 /**
1241  * batadv_mcast_free - free the multicast optimizations structures
1242  * @bat_priv: the bat priv with all the soft interface information
1243  */
1244 void batadv_mcast_free(struct batadv_priv *bat_priv)
1245 {
1246 	batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_MCAST, 2);
1247 	batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_MCAST, 2);
1248 
1249 	spin_lock_bh(&bat_priv->tt.commit_lock);
1250 	batadv_mcast_mla_tt_retract(bat_priv, NULL);
1251 	spin_unlock_bh(&bat_priv->tt.commit_lock);
1252 }
1253 
1254 /**
1255  * batadv_mcast_purge_orig - reset originator global mcast state modifications
1256  * @orig: the originator which is going to get purged
1257  */
1258 void batadv_mcast_purge_orig(struct batadv_orig_node *orig)
1259 {
1260 	struct batadv_priv *bat_priv = orig->bat_priv;
1261 
1262 	spin_lock_bh(&orig->mcast_handler_lock);
1263 
1264 	if (!test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities) &&
1265 	    test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capa_initialized))
1266 		atomic_dec(&bat_priv->mcast.num_disabled);
1267 
1268 	batadv_mcast_want_unsnoop_update(bat_priv, orig, BATADV_NO_FLAGS);
1269 	batadv_mcast_want_ipv4_update(bat_priv, orig, BATADV_NO_FLAGS);
1270 	batadv_mcast_want_ipv6_update(bat_priv, orig, BATADV_NO_FLAGS);
1271 
1272 	spin_unlock_bh(&orig->mcast_handler_lock);
1273 }
1274