1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (C) B.A.T.M.A.N. contributors:
3 *
4 * Linus L��ssing
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/container_of.h>
15#include <linux/errno.h>
16#include <linux/etherdevice.h>
17#include <linux/gfp.h>
18#include <linux/icmpv6.h>
19#include <linux/if_bridge.h>
20#include <linux/if_ether.h>
21#include <linux/igmp.h>
22#include <linux/in.h>
23#include <linux/in6.h>
24#include <linux/inetdevice.h>
25#include <linux/ip.h>
26#include <linux/ipv6.h>
27#include <linux/jiffies.h>
28#include <linux/list.h>
29#include <linux/lockdep.h>
30#include <linux/netdevice.h>
31#include <linux/netlink.h>
32#include <linux/printk.h>
33#include <linux/rculist.h>
34#include <linux/rcupdate.h>
35#include <linux/skbuff.h>
36#include <linux/slab.h>
37#include <linux/spinlock.h>
38#include <linux/sprintf.h>
39#include <linux/stddef.h>
40#include <linux/string.h>
41#include <linux/types.h>
42#include <linux/workqueue.h>
43#include <net/addrconf.h>
44#include <net/genetlink.h>
45#include <net/if_inet6.h>
46#include <net/ip.h>
47#include <net/ipv6.h>
48#include <net/netlink.h>
49#include <net/sock.h>
50#include <uapi/linux/batadv_packet.h>
51#include <uapi/linux/batman_adv.h>
52
53#include "bridge_loop_avoidance.h"
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
63static 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 */
69static 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 */
85static 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 && !netif_is_bridge_master(upper));
93
94	dev_hold(upper);
95	rcu_read_unlock();
96
97	return upper;
98}
99
100/**
101 * batadv_mcast_mla_rtr_flags_softif_get_ipv4() - get mcast router flags from
102 *  node for IPv4
103 * @dev: the interface to check
104 *
105 * Checks the presence of an IPv4 multicast router on this node.
106 *
107 * Caller needs to hold rcu read lock.
108 *
109 * Return: BATADV_NO_FLAGS if present, BATADV_MCAST_WANT_NO_RTR4 otherwise.
110 */
111static u8 batadv_mcast_mla_rtr_flags_softif_get_ipv4(struct net_device *dev)
112{
113	struct in_device *in_dev = __in_dev_get_rcu(dev);
114
115	if (in_dev && IN_DEV_MFORWARD(in_dev))
116		return BATADV_NO_FLAGS;
117	else
118		return BATADV_MCAST_WANT_NO_RTR4;
119}
120
121/**
122 * batadv_mcast_mla_rtr_flags_softif_get_ipv6() - get mcast router flags from
123 *  node for IPv6
124 * @dev: the interface to check
125 *
126 * Checks the presence of an IPv6 multicast router on this node.
127 *
128 * Caller needs to hold rcu read lock.
129 *
130 * Return: BATADV_NO_FLAGS if present, BATADV_MCAST_WANT_NO_RTR6 otherwise.
131 */
132#if IS_ENABLED(CONFIG_IPV6_MROUTE)
133static u8 batadv_mcast_mla_rtr_flags_softif_get_ipv6(struct net_device *dev)
134{
135	struct inet6_dev *in6_dev = __in6_dev_get(dev);
136
137	if (in6_dev && atomic_read(&in6_dev->cnf.mc_forwarding))
138		return BATADV_NO_FLAGS;
139	else
140		return BATADV_MCAST_WANT_NO_RTR6;
141}
142#else
143static inline u8
144batadv_mcast_mla_rtr_flags_softif_get_ipv6(struct net_device *dev)
145{
146	return BATADV_MCAST_WANT_NO_RTR6;
147}
148#endif
149
150/**
151 * batadv_mcast_mla_rtr_flags_softif_get() - get mcast router flags from node
152 * @bat_priv: the bat priv with all the soft interface information
153 * @bridge: bridge interface on top of the soft_iface if present,
154 *  otherwise pass NULL
155 *
156 * Checks the presence of IPv4 and IPv6 multicast routers on this
157 * node.
158 *
159 * Return:
160 *	BATADV_NO_FLAGS: Both an IPv4 and IPv6 multicast router is present
161 *	BATADV_MCAST_WANT_NO_RTR4: No IPv4 multicast router is present
162 *	BATADV_MCAST_WANT_NO_RTR6: No IPv6 multicast router is present
163 *	The former two OR'd: no multicast router is present
164 */
165static u8 batadv_mcast_mla_rtr_flags_softif_get(struct batadv_priv *bat_priv,
166						struct net_device *bridge)
167{
168	struct net_device *dev = bridge ? bridge : bat_priv->soft_iface;
169	u8 flags = BATADV_NO_FLAGS;
170
171	rcu_read_lock();
172
173	flags |= batadv_mcast_mla_rtr_flags_softif_get_ipv4(dev);
174	flags |= batadv_mcast_mla_rtr_flags_softif_get_ipv6(dev);
175
176	rcu_read_unlock();
177
178	return flags;
179}
180
181/**
182 * batadv_mcast_mla_rtr_flags_bridge_get() - get mcast router flags from bridge
183 * @bat_priv: the bat priv with all the soft interface information
184 * @bridge: bridge interface on top of the soft_iface if present,
185 *  otherwise pass NULL
186 *
187 * Checks the presence of IPv4 and IPv6 multicast routers behind a bridge.
188 *
189 * Return:
190 *	BATADV_NO_FLAGS: Both an IPv4 and IPv6 multicast router is present
191 *	BATADV_MCAST_WANT_NO_RTR4: No IPv4 multicast router is present
192 *	BATADV_MCAST_WANT_NO_RTR6: No IPv6 multicast router is present
193 *	The former two OR'd: no multicast router is present
194 */
195static u8 batadv_mcast_mla_rtr_flags_bridge_get(struct batadv_priv *bat_priv,
196						struct net_device *bridge)
197{
198	struct net_device *dev = bat_priv->soft_iface;
199	u8 flags = BATADV_NO_FLAGS;
200
201	if (!bridge)
202		return BATADV_MCAST_WANT_NO_RTR4 | BATADV_MCAST_WANT_NO_RTR6;
203
204	if (!br_multicast_has_router_adjacent(dev, ETH_P_IP))
205		flags |= BATADV_MCAST_WANT_NO_RTR4;
206	if (!br_multicast_has_router_adjacent(dev, ETH_P_IPV6))
207		flags |= BATADV_MCAST_WANT_NO_RTR6;
208
209	return flags;
210}
211
212/**
213 * batadv_mcast_mla_rtr_flags_get() - get multicast router flags
214 * @bat_priv: the bat priv with all the soft interface information
215 * @bridge: bridge interface on top of the soft_iface if present,
216 *  otherwise pass NULL
217 *
218 * Checks the presence of IPv4 and IPv6 multicast routers on this
219 * node or behind its bridge.
220 *
221 * Return:
222 *	BATADV_NO_FLAGS: Both an IPv4 and IPv6 multicast router is present
223 *	BATADV_MCAST_WANT_NO_RTR4: No IPv4 multicast router is present
224 *	BATADV_MCAST_WANT_NO_RTR6: No IPv6 multicast router is present
225 *	The former two OR'd: no multicast router is present
226 */
227static u8 batadv_mcast_mla_rtr_flags_get(struct batadv_priv *bat_priv,
228					 struct net_device *bridge)
229{
230	u8 flags = BATADV_MCAST_WANT_NO_RTR4 | BATADV_MCAST_WANT_NO_RTR6;
231
232	flags &= batadv_mcast_mla_rtr_flags_softif_get(bat_priv, bridge);
233	flags &= batadv_mcast_mla_rtr_flags_bridge_get(bat_priv, bridge);
234
235	return flags;
236}
237
238/**
239 * batadv_mcast_mla_forw_flags_get() - get multicast forwarding flags
240 * @bat_priv: the bat priv with all the soft interface information
241 *
242 * Checks if all active hard interfaces have an MTU larger or equal to 1280
243 * bytes (IPv6 minimum MTU).
244 *
245 * Return: BATADV_MCAST_HAVE_MC_PTYPE_CAPA if yes, BATADV_NO_FLAGS otherwise.
246 */
247static u8 batadv_mcast_mla_forw_flags_get(struct batadv_priv *bat_priv)
248{
249	const struct batadv_hard_iface *hard_iface;
250
251	rcu_read_lock();
252	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
253		if (hard_iface->if_status != BATADV_IF_ACTIVE)
254			continue;
255
256		if (hard_iface->soft_iface != bat_priv->soft_iface)
257			continue;
258
259		if (hard_iface->net_dev->mtu < IPV6_MIN_MTU) {
260			rcu_read_unlock();
261			return BATADV_NO_FLAGS;
262		}
263	}
264	rcu_read_unlock();
265
266	return BATADV_MCAST_HAVE_MC_PTYPE_CAPA;
267}
268
269/**
270 * batadv_mcast_mla_flags_get() - get the new multicast flags
271 * @bat_priv: the bat priv with all the soft interface information
272 *
273 * Return: A set of flags for the current/next TVLV, querier and
274 * bridge state.
275 */
276static struct batadv_mcast_mla_flags
277batadv_mcast_mla_flags_get(struct batadv_priv *bat_priv)
278{
279	struct net_device *dev = bat_priv->soft_iface;
280	struct batadv_mcast_querier_state *qr4, *qr6;
281	struct batadv_mcast_mla_flags mla_flags;
282	struct net_device *bridge;
283
284	bridge = batadv_mcast_get_bridge(dev);
285
286	memset(&mla_flags, 0, sizeof(mla_flags));
287	mla_flags.enabled = 1;
288	mla_flags.tvlv_flags |= batadv_mcast_mla_rtr_flags_get(bat_priv,
289							       bridge);
290	mla_flags.tvlv_flags |= batadv_mcast_mla_forw_flags_get(bat_priv);
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 */
342static 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 */
368static int
369batadv_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)
435static int
436batadv_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	for (pmc6 = rcu_dereference(in6_dev->mc_list);
458	     pmc6;
459	     pmc6 = rcu_dereference(pmc6->next)) {
460		if (IPV6_ADDR_MC_SCOPE(&pmc6->mca_addr) <
461		    IPV6_ADDR_SCOPE_LINKLOCAL)
462			continue;
463
464		if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
465		    ipv6_addr_is_ll_all_nodes(&pmc6->mca_addr))
466			continue;
467
468		if (!(flags->tvlv_flags & BATADV_MCAST_WANT_NO_RTR6) &&
469		    IPV6_ADDR_MC_SCOPE(&pmc6->mca_addr) >
470		    IPV6_ADDR_SCOPE_LINKLOCAL)
471			continue;
472
473		ipv6_eth_mc_map(&pmc6->mca_addr, mcast_addr);
474
475		if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
476			continue;
477
478		new = kmalloc(sizeof(*new), GFP_ATOMIC);
479		if (!new) {
480			ret = -ENOMEM;
481			break;
482		}
483
484		ether_addr_copy(new->addr, mcast_addr);
485		hlist_add_head(&new->list, mcast_list);
486		ret++;
487	}
488	rcu_read_unlock();
489
490	return ret;
491}
492#else
493static inline int
494batadv_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, collect 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 */
521static int
522batadv_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
542out:
543	dev_put(bridge);
544
545	return ret4 + ret6;
546}
547
548/**
549 * batadv_mcast_mla_br_addr_cpy() - copy a bridge multicast address
550 * @dst: destination to write to - a multicast MAC address
551 * @src: source to read from - a multicast IP address
552 *
553 * Converts a given multicast IPv4/IPv6 address from a bridge
554 * to its matching multicast MAC address and copies it into the given
555 * destination buffer.
556 *
557 * Caller needs to make sure the destination buffer can hold
558 * at least ETH_ALEN bytes.
559 */
560static void batadv_mcast_mla_br_addr_cpy(char *dst, const struct br_ip *src)
561{
562	if (src->proto == htons(ETH_P_IP))
563		ip_eth_mc_map(src->dst.ip4, dst);
564#if IS_ENABLED(CONFIG_IPV6)
565	else if (src->proto == htons(ETH_P_IPV6))
566		ipv6_eth_mc_map(&src->dst.ip6, dst);
567#endif
568	else
569		eth_zero_addr(dst);
570}
571
572/**
573 * batadv_mcast_mla_bridge_get() - get bridged-in multicast listeners
574 * @dev: a bridge slave whose bridge to collect multicast addresses from
575 * @mcast_list: a list to put found addresses into
576 * @flags: flags indicating the new multicast state
577 *
578 * Collects multicast addresses of multicast listeners residing
579 * on foreign, non-mesh devices which we gave access to our mesh via
580 * a bridge on top of the given soft interface, dev, in the given
581 * mcast_list.
582 *
583 * Return: -ENOMEM on memory allocation error or the number of
584 * items added to the mcast_list otherwise.
585 */
586static int batadv_mcast_mla_bridge_get(struct net_device *dev,
587				       struct hlist_head *mcast_list,
588				       struct batadv_mcast_mla_flags *flags)
589{
590	struct list_head bridge_mcast_list = LIST_HEAD_INIT(bridge_mcast_list);
591	struct br_ip_list *br_ip_entry, *tmp;
592	u8 tvlv_flags = flags->tvlv_flags;
593	struct batadv_hw_addr *new;
594	u8 mcast_addr[ETH_ALEN];
595	int ret;
596
597	/* we don't need to detect these devices/listeners, the IGMP/MLD
598	 * snooping code of the Linux bridge already does that for us
599	 */
600	ret = br_multicast_list_adjacent(dev, &bridge_mcast_list);
601	if (ret < 0)
602		goto out;
603
604	list_for_each_entry(br_ip_entry, &bridge_mcast_list, list) {
605		if (br_ip_entry->addr.proto == htons(ETH_P_IP)) {
606			if (tvlv_flags & BATADV_MCAST_WANT_ALL_IPV4)
607				continue;
608
609			if (tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
610			    ipv4_is_local_multicast(br_ip_entry->addr.dst.ip4))
611				continue;
612
613			if (!(tvlv_flags & BATADV_MCAST_WANT_NO_RTR4) &&
614			    !ipv4_is_local_multicast(br_ip_entry->addr.dst.ip4))
615				continue;
616		}
617
618#if IS_ENABLED(CONFIG_IPV6)
619		if (br_ip_entry->addr.proto == htons(ETH_P_IPV6)) {
620			if (tvlv_flags & BATADV_MCAST_WANT_ALL_IPV6)
621				continue;
622
623			if (tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
624			    ipv6_addr_is_ll_all_nodes(&br_ip_entry->addr.dst.ip6))
625				continue;
626
627			if (!(tvlv_flags & BATADV_MCAST_WANT_NO_RTR6) &&
628			    IPV6_ADDR_MC_SCOPE(&br_ip_entry->addr.dst.ip6) >
629			    IPV6_ADDR_SCOPE_LINKLOCAL)
630				continue;
631		}
632#endif
633
634		batadv_mcast_mla_br_addr_cpy(mcast_addr, &br_ip_entry->addr);
635		if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
636			continue;
637
638		new = kmalloc(sizeof(*new), GFP_ATOMIC);
639		if (!new) {
640			ret = -ENOMEM;
641			break;
642		}
643
644		ether_addr_copy(new->addr, mcast_addr);
645		hlist_add_head(&new->list, mcast_list);
646	}
647
648out:
649	list_for_each_entry_safe(br_ip_entry, tmp, &bridge_mcast_list, list) {
650		list_del(&br_ip_entry->list);
651		kfree(br_ip_entry);
652	}
653
654	return ret;
655}
656
657/**
658 * batadv_mcast_mla_list_free() - free a list of multicast addresses
659 * @mcast_list: the list to free
660 *
661 * Removes and frees all items in the given mcast_list.
662 */
663static void batadv_mcast_mla_list_free(struct hlist_head *mcast_list)
664{
665	struct batadv_hw_addr *mcast_entry;
666	struct hlist_node *tmp;
667
668	hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) {
669		hlist_del(&mcast_entry->list);
670		kfree(mcast_entry);
671	}
672}
673
674/**
675 * batadv_mcast_mla_tt_retract() - clean up multicast listener announcements
676 * @bat_priv: the bat priv with all the soft interface information
677 * @mcast_list: a list of addresses which should _not_ be removed
678 *
679 * Retracts the announcement of any multicast listener from the
680 * translation table except the ones listed in the given mcast_list.
681 *
682 * If mcast_list is NULL then all are retracted.
683 */
684static void batadv_mcast_mla_tt_retract(struct batadv_priv *bat_priv,
685					struct hlist_head *mcast_list)
686{
687	struct batadv_hw_addr *mcast_entry;
688	struct hlist_node *tmp;
689
690	hlist_for_each_entry_safe(mcast_entry, tmp, &bat_priv->mcast.mla_list,
691				  list) {
692		if (mcast_list &&
693		    batadv_mcast_mla_is_duplicate(mcast_entry->addr,
694						  mcast_list))
695			continue;
696
697		batadv_tt_local_remove(bat_priv, mcast_entry->addr,
698				       BATADV_NO_FLAGS,
699				       "mcast TT outdated", false);
700
701		hlist_del(&mcast_entry->list);
702		kfree(mcast_entry);
703	}
704}
705
706/**
707 * batadv_mcast_mla_tt_add() - add multicast listener announcements
708 * @bat_priv: the bat priv with all the soft interface information
709 * @mcast_list: a list of addresses which are going to get added
710 *
711 * Adds multicast listener announcements from the given mcast_list to the
712 * translation table if they have not been added yet.
713 */
714static void batadv_mcast_mla_tt_add(struct batadv_priv *bat_priv,
715				    struct hlist_head *mcast_list)
716{
717	struct batadv_hw_addr *mcast_entry;
718	struct hlist_node *tmp;
719
720	if (!mcast_list)
721		return;
722
723	hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) {
724		if (batadv_mcast_mla_is_duplicate(mcast_entry->addr,
725						  &bat_priv->mcast.mla_list))
726			continue;
727
728		if (!batadv_tt_local_add(bat_priv->soft_iface,
729					 mcast_entry->addr, BATADV_NO_FLAGS,
730					 BATADV_NULL_IFINDEX, BATADV_NO_MARK))
731			continue;
732
733		hlist_del(&mcast_entry->list);
734		hlist_add_head(&mcast_entry->list, &bat_priv->mcast.mla_list);
735	}
736}
737
738/**
739 * batadv_mcast_querier_log() - debug output regarding the querier status on
740 *  link
741 * @bat_priv: the bat priv with all the soft interface information
742 * @str_proto: a string for the querier protocol (e.g. "IGMP" or "MLD")
743 * @old_state: the previous querier state on our link
744 * @new_state: the new querier state on our link
745 *
746 * Outputs debug messages to the logging facility with log level 'mcast'
747 * regarding changes to the querier status on the link which are relevant
748 * to our multicast optimizations.
749 *
750 * Usually this is about whether a querier appeared or vanished in
751 * our mesh or whether the querier is in the suboptimal position of being
752 * behind our local bridge segment: Snooping switches will directly
753 * forward listener reports to the querier, therefore batman-adv and
754 * the bridge will potentially not see these listeners - the querier is
755 * potentially shadowing listeners from us then.
756 *
757 * This is only interesting for nodes with a bridge on top of their
758 * soft interface.
759 */
760static void
761batadv_mcast_querier_log(struct batadv_priv *bat_priv, char *str_proto,
762			 struct batadv_mcast_querier_state *old_state,
763			 struct batadv_mcast_querier_state *new_state)
764{
765	if (!old_state->exists && new_state->exists)
766		batadv_info(bat_priv->soft_iface, "%s Querier appeared\n",
767			    str_proto);
768	else if (old_state->exists && !new_state->exists)
769		batadv_info(bat_priv->soft_iface,
770			    "%s Querier disappeared - multicast optimizations disabled\n",
771			    str_proto);
772	else if (!bat_priv->mcast.mla_flags.bridged && !new_state->exists)
773		batadv_info(bat_priv->soft_iface,
774			    "No %s Querier present - multicast optimizations disabled\n",
775			    str_proto);
776
777	if (new_state->exists) {
778		if ((!old_state->shadowing && new_state->shadowing) ||
779		    (!old_state->exists && new_state->shadowing))
780			batadv_dbg(BATADV_DBG_MCAST, bat_priv,
781				   "%s Querier is behind our bridged segment: Might shadow listeners\n",
782				   str_proto);
783		else if (old_state->shadowing && !new_state->shadowing)
784			batadv_dbg(BATADV_DBG_MCAST, bat_priv,
785				   "%s Querier is not behind our bridged segment\n",
786				   str_proto);
787	}
788}
789
790/**
791 * batadv_mcast_bridge_log() - debug output for topology changes in bridged
792 *  setups
793 * @bat_priv: the bat priv with all the soft interface information
794 * @new_flags: flags indicating the new multicast state
795 *
796 * If no bridges are ever used on this node, then this function does nothing.
797 *
798 * Otherwise this function outputs debug information to the 'mcast' log level
799 * which might be relevant to our multicast optimizations.
800 *
801 * More precisely, it outputs information when a bridge interface is added or
802 * removed from a soft interface. And when a bridge is present, it further
803 * outputs information about the querier state which is relevant for the
804 * multicast flags this node is going to set.
805 */
806static void
807batadv_mcast_bridge_log(struct batadv_priv *bat_priv,
808			struct batadv_mcast_mla_flags *new_flags)
809{
810	struct batadv_mcast_mla_flags *old_flags = &bat_priv->mcast.mla_flags;
811
812	if (!old_flags->bridged && new_flags->bridged)
813		batadv_dbg(BATADV_DBG_MCAST, bat_priv,
814			   "Bridge added: Setting Unsnoopables(U)-flag\n");
815	else if (old_flags->bridged && !new_flags->bridged)
816		batadv_dbg(BATADV_DBG_MCAST, bat_priv,
817			   "Bridge removed: Unsetting Unsnoopables(U)-flag\n");
818
819	if (new_flags->bridged) {
820		batadv_mcast_querier_log(bat_priv, "IGMP",
821					 &old_flags->querier_ipv4,
822					 &new_flags->querier_ipv4);
823		batadv_mcast_querier_log(bat_priv, "MLD",
824					 &old_flags->querier_ipv6,
825					 &new_flags->querier_ipv6);
826	}
827}
828
829/**
830 * batadv_mcast_flags_log() - output debug information about mcast flag changes
831 * @bat_priv: the bat priv with all the soft interface information
832 * @flags: TVLV flags indicating the new multicast state
833 *
834 * Whenever the multicast TVLV flags this node announces change, this function
835 * should be used to notify userspace about the change.
836 */
837static void batadv_mcast_flags_log(struct batadv_priv *bat_priv, u8 flags)
838{
839	bool old_enabled = bat_priv->mcast.mla_flags.enabled;
840	u8 old_flags = bat_priv->mcast.mla_flags.tvlv_flags;
841	char str_old_flags[] = "[.... . .]";
842
843	sprintf(str_old_flags, "[%c%c%c%s%s%c]",
844		(old_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) ? 'U' : '.',
845		(old_flags & BATADV_MCAST_WANT_ALL_IPV4) ? '4' : '.',
846		(old_flags & BATADV_MCAST_WANT_ALL_IPV6) ? '6' : '.',
847		!(old_flags & BATADV_MCAST_WANT_NO_RTR4) ? "R4" : ". ",
848		!(old_flags & BATADV_MCAST_WANT_NO_RTR6) ? "R6" : ". ",
849		!(old_flags & BATADV_MCAST_HAVE_MC_PTYPE_CAPA) ? 'P' : '.');
850
851	batadv_dbg(BATADV_DBG_MCAST, bat_priv,
852		   "Changing multicast flags from '%s' to '[%c%c%c%s%s%c]'\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		   !(flags & BATADV_MCAST_HAVE_MC_PTYPE_CAPA) ? 'P' : '.');
860}
861
862/**
863 * batadv_mcast_mla_flags_update() - update multicast flags
864 * @bat_priv: the bat priv with all the soft interface information
865 * @flags: flags indicating the new multicast state
866 *
867 * Updates the own multicast tvlv with our current multicast related settings,
868 * capabilities and inabilities.
869 */
870static void
871batadv_mcast_mla_flags_update(struct batadv_priv *bat_priv,
872			      struct batadv_mcast_mla_flags *flags)
873{
874	struct batadv_tvlv_mcast_data mcast_data;
875
876	if (!memcmp(flags, &bat_priv->mcast.mla_flags, sizeof(*flags)))
877		return;
878
879	batadv_mcast_bridge_log(bat_priv, flags);
880	batadv_mcast_flags_log(bat_priv, flags->tvlv_flags);
881
882	mcast_data.flags = flags->tvlv_flags;
883	memset(mcast_data.reserved, 0, sizeof(mcast_data.reserved));
884
885	batadv_tvlv_container_register(bat_priv, BATADV_TVLV_MCAST, 2,
886				       &mcast_data, sizeof(mcast_data));
887
888	bat_priv->mcast.mla_flags = *flags;
889}
890
891/**
892 * __batadv_mcast_mla_update() - update the own MLAs
893 * @bat_priv: the bat priv with all the soft interface information
894 *
895 * Updates the own multicast listener announcements in the translation
896 * table as well as the own, announced multicast tvlv container.
897 *
898 * Note that non-conflicting reads and writes to bat_priv->mcast.mla_list
899 * in batadv_mcast_mla_tt_retract() and batadv_mcast_mla_tt_add() are
900 * ensured by the non-parallel execution of the worker this function
901 * belongs to.
902 */
903static void __batadv_mcast_mla_update(struct batadv_priv *bat_priv)
904{
905	struct net_device *soft_iface = bat_priv->soft_iface;
906	struct hlist_head mcast_list = HLIST_HEAD_INIT;
907	struct batadv_mcast_mla_flags flags;
908	int ret;
909
910	flags = batadv_mcast_mla_flags_get(bat_priv);
911
912	ret = batadv_mcast_mla_softif_get(soft_iface, &mcast_list, &flags);
913	if (ret < 0)
914		goto out;
915
916	ret = batadv_mcast_mla_bridge_get(soft_iface, &mcast_list, &flags);
917	if (ret < 0)
918		goto out;
919
920	spin_lock(&bat_priv->mcast.mla_lock);
921	batadv_mcast_mla_tt_retract(bat_priv, &mcast_list);
922	batadv_mcast_mla_tt_add(bat_priv, &mcast_list);
923	batadv_mcast_mla_flags_update(bat_priv, &flags);
924	spin_unlock(&bat_priv->mcast.mla_lock);
925
926out:
927	batadv_mcast_mla_list_free(&mcast_list);
928}
929
930/**
931 * batadv_mcast_mla_update() - update the own MLAs
932 * @work: kernel work struct
933 *
934 * Updates the own multicast listener announcements in the translation
935 * table as well as the own, announced multicast tvlv container.
936 *
937 * In the end, reschedules the work timer.
938 */
939static void batadv_mcast_mla_update(struct work_struct *work)
940{
941	struct delayed_work *delayed_work;
942	struct batadv_priv_mcast *priv_mcast;
943	struct batadv_priv *bat_priv;
944
945	delayed_work = to_delayed_work(work);
946	priv_mcast = container_of(delayed_work, struct batadv_priv_mcast, work);
947	bat_priv = container_of(priv_mcast, struct batadv_priv, mcast);
948
949	__batadv_mcast_mla_update(bat_priv);
950	batadv_mcast_start_timer(bat_priv);
951}
952
953/**
954 * batadv_mcast_is_report_ipv4() -���check for IGMP reports
955 * @skb: the ethernet frame destined for the mesh
956 *
957 * This call might reallocate skb data.
958 *
959 * Checks whether the given frame is a valid IGMP report.
960 *
961 * Return: If so then true, otherwise false.
962 */
963static bool batadv_mcast_is_report_ipv4(struct sk_buff *skb)
964{
965	if (ip_mc_check_igmp(skb) < 0)
966		return false;
967
968	switch (igmp_hdr(skb)->type) {
969	case IGMP_HOST_MEMBERSHIP_REPORT:
970	case IGMPV2_HOST_MEMBERSHIP_REPORT:
971	case IGMPV3_HOST_MEMBERSHIP_REPORT:
972		return true;
973	}
974
975	return false;
976}
977
978/**
979 * batadv_mcast_forw_mode_check_ipv4() - check for optimized forwarding
980 *  potential
981 * @bat_priv: the bat priv with all the soft interface information
982 * @skb: the IPv4 packet to check
983 * @is_unsnoopable: stores whether the destination is snoopable
984 * @is_routable: stores whether the destination is routable
985 *
986 * Checks whether the given IPv4 packet has the potential to be forwarded with a
987 * mode more optimal than classic flooding.
988 *
989 * Return: If so then 0. Otherwise -EINVAL or -ENOMEM in case of memory
990 * allocation failure.
991 */
992static int batadv_mcast_forw_mode_check_ipv4(struct batadv_priv *bat_priv,
993					     struct sk_buff *skb,
994					     bool *is_unsnoopable,
995					     int *is_routable)
996{
997	struct iphdr *iphdr;
998
999	/* We might fail due to out-of-memory -> drop it */
1000	if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*iphdr)))
1001		return -ENOMEM;
1002
1003	if (batadv_mcast_is_report_ipv4(skb))
1004		return -EINVAL;
1005
1006	iphdr = ip_hdr(skb);
1007
1008	/* link-local multicast listeners behind a bridge are
1009	 * not snoopable (see RFC4541, section 2.1.2.2)
1010	 */
1011	if (ipv4_is_local_multicast(iphdr->daddr))
1012		*is_unsnoopable = true;
1013	else
1014		*is_routable = ETH_P_IP;
1015
1016	return 0;
1017}
1018
1019/**
1020 * batadv_mcast_is_report_ipv6() - check for MLD reports
1021 * @skb: the ethernet frame destined for the mesh
1022 *
1023 * This call might reallocate skb data.
1024 *
1025 * Checks whether the given frame is a valid MLD report.
1026 *
1027 * Return: If so then true, otherwise false.
1028 */
1029static bool batadv_mcast_is_report_ipv6(struct sk_buff *skb)
1030{
1031	if (ipv6_mc_check_mld(skb) < 0)
1032		return false;
1033
1034	switch (icmp6_hdr(skb)->icmp6_type) {
1035	case ICMPV6_MGM_REPORT:
1036	case ICMPV6_MLD2_REPORT:
1037		return true;
1038	}
1039
1040	return false;
1041}
1042
1043/**
1044 * batadv_mcast_forw_mode_check_ipv6() - check for optimized forwarding
1045 *  potential
1046 * @bat_priv: the bat priv with all the soft interface information
1047 * @skb: the IPv6 packet to check
1048 * @is_unsnoopable: stores whether the destination is snoopable
1049 * @is_routable: stores whether the destination is routable
1050 *
1051 * Checks whether the given IPv6 packet has the potential to be forwarded with a
1052 * mode more optimal than classic flooding.
1053 *
1054 * Return: If so then 0. Otherwise -EINVAL is or -ENOMEM if we are out of memory
1055 */
1056static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv,
1057					     struct sk_buff *skb,
1058					     bool *is_unsnoopable,
1059					     int *is_routable)
1060{
1061	struct ipv6hdr *ip6hdr;
1062
1063	/* We might fail due to out-of-memory -> drop it */
1064	if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*ip6hdr)))
1065		return -ENOMEM;
1066
1067	if (batadv_mcast_is_report_ipv6(skb))
1068		return -EINVAL;
1069
1070	ip6hdr = ipv6_hdr(skb);
1071
1072	if (IPV6_ADDR_MC_SCOPE(&ip6hdr->daddr) < IPV6_ADDR_SCOPE_LINKLOCAL)
1073		return -EINVAL;
1074
1075	/* link-local-all-nodes multicast listeners behind a bridge are
1076	 * not snoopable (see RFC4541, section 3, paragraph 3)
1077	 */
1078	if (ipv6_addr_is_ll_all_nodes(&ip6hdr->daddr))
1079		*is_unsnoopable = true;
1080	else if (IPV6_ADDR_MC_SCOPE(&ip6hdr->daddr) > IPV6_ADDR_SCOPE_LINKLOCAL)
1081		*is_routable = ETH_P_IPV6;
1082
1083	return 0;
1084}
1085
1086/**
1087 * batadv_mcast_forw_mode_check() - check for optimized forwarding potential
1088 * @bat_priv: the bat priv with all the soft interface information
1089 * @skb: the multicast frame to check
1090 * @is_unsnoopable: stores whether the destination is snoopable
1091 * @is_routable: stores whether the destination is routable
1092 *
1093 * Checks whether the given multicast ethernet frame has the potential to be
1094 * forwarded with a mode more optimal than classic flooding.
1095 *
1096 * Return: If so then 0. Otherwise -EINVAL is or -ENOMEM if we are out of memory
1097 */
1098static int batadv_mcast_forw_mode_check(struct batadv_priv *bat_priv,
1099					struct sk_buff *skb,
1100					bool *is_unsnoopable,
1101					int *is_routable)
1102{
1103	struct ethhdr *ethhdr = eth_hdr(skb);
1104
1105	if (!atomic_read(&bat_priv->multicast_mode))
1106		return -EINVAL;
1107
1108	switch (ntohs(ethhdr->h_proto)) {
1109	case ETH_P_IP:
1110		return batadv_mcast_forw_mode_check_ipv4(bat_priv, skb,
1111							 is_unsnoopable,
1112							 is_routable);
1113	case ETH_P_IPV6:
1114		if (!IS_ENABLED(CONFIG_IPV6))
1115			return -EINVAL;
1116
1117		return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb,
1118							 is_unsnoopable,
1119							 is_routable);
1120	default:
1121		return -EINVAL;
1122	}
1123}
1124
1125/**
1126 * batadv_mcast_forw_want_all_ip_count() - count nodes with unspecific mcast
1127 *  interest
1128 * @bat_priv: the bat priv with all the soft interface information
1129 * @ethhdr: ethernet header of a packet
1130 *
1131 * Return: the number of nodes which want all IPv4 multicast traffic if the
1132 * given ethhdr is from an IPv4 packet or the number of nodes which want all
1133 * IPv6 traffic if it matches an IPv6 packet.
1134 */
1135static int batadv_mcast_forw_want_all_ip_count(struct batadv_priv *bat_priv,
1136					       struct ethhdr *ethhdr)
1137{
1138	switch (ntohs(ethhdr->h_proto)) {
1139	case ETH_P_IP:
1140		return atomic_read(&bat_priv->mcast.num_want_all_ipv4);
1141	case ETH_P_IPV6:
1142		return atomic_read(&bat_priv->mcast.num_want_all_ipv6);
1143	default:
1144		/* we shouldn't be here... */
1145		return 0;
1146	}
1147}
1148
1149/**
1150 * batadv_mcast_forw_rtr_count() - count nodes with a multicast router
1151 * @bat_priv: the bat priv with all the soft interface information
1152 * @protocol: the ethernet protocol type to count multicast routers for
1153 *
1154 * Return: the number of nodes which want all routable IPv4 multicast traffic
1155 * if the protocol is ETH_P_IP or the number of nodes which want all routable
1156 * IPv6 traffic if the protocol is ETH_P_IPV6. Otherwise returns 0.
1157 */
1158
1159static int batadv_mcast_forw_rtr_count(struct batadv_priv *bat_priv,
1160				       int protocol)
1161{
1162	switch (protocol) {
1163	case ETH_P_IP:
1164		return atomic_read(&bat_priv->mcast.num_want_all_rtr4);
1165	case ETH_P_IPV6:
1166		return atomic_read(&bat_priv->mcast.num_want_all_rtr6);
1167	default:
1168		return 0;
1169	}
1170}
1171
1172/**
1173 * batadv_mcast_forw_mode_by_count() - get forwarding mode by count
1174 * @bat_priv: the bat priv with all the soft interface information
1175 * @skb: the multicast packet to check
1176 * @vid: the vlan identifier
1177 * @is_routable: stores whether the destination is routable
1178 * @count: the number of originators the multicast packet need to be sent to
1179 *
1180 * For a multicast packet with multiple destination originators, checks which
1181 * mode to use. For BATADV_FORW_MCAST it also encapsulates the packet with a
1182 * complete batman-adv multicast header.
1183 *
1184 * Return:
1185 *	BATADV_FORW_MCAST: If all nodes have multicast packet routing
1186 *	capabilities and an MTU >= 1280 on all hard interfaces (including us)
1187 *	and the encapsulated multicast packet with all destination addresses
1188 *	would still fit into an 1280 bytes batman-adv multicast packet
1189 *	(excluding the outer ethernet frame) and we could successfully push
1190 *	the full batman-adv multicast packet header.
1191 *	BATADV_FORW_UCASTS: If the packet cannot be sent in a batman-adv
1192 *	multicast packet and the amount of batman-adv unicast packets needed
1193 *	is smaller or equal to the configured multicast fanout.
1194 *	BATADV_FORW_BCAST: Otherwise.
1195 */
1196static enum batadv_forw_mode
1197batadv_mcast_forw_mode_by_count(struct batadv_priv *bat_priv,
1198				struct sk_buff *skb, unsigned short vid,
1199				int is_routable, int count)
1200{
1201	unsigned int mcast_hdrlen = batadv_mcast_forw_packet_hdrlen(count);
1202	u8 own_tvlv_flags = bat_priv->mcast.mla_flags.tvlv_flags;
1203
1204	if (!atomic_read(&bat_priv->mcast.num_no_mc_ptype_capa) &&
1205	    own_tvlv_flags & BATADV_MCAST_HAVE_MC_PTYPE_CAPA &&
1206	    skb->len + mcast_hdrlen <= IPV6_MIN_MTU &&
1207	    batadv_mcast_forw_push(bat_priv, skb, vid, is_routable, count))
1208		return BATADV_FORW_MCAST;
1209
1210	if (count <= atomic_read(&bat_priv->multicast_fanout))
1211		return BATADV_FORW_UCASTS;
1212
1213	return BATADV_FORW_BCAST;
1214}
1215
1216/**
1217 * batadv_mcast_forw_mode() - check on how to forward a multicast packet
1218 * @bat_priv: the bat priv with all the soft interface information
1219 * @skb: the multicast packet to check
1220 * @vid: the vlan identifier
1221 * @is_routable: stores whether the destination is routable
1222 *
1223 * Return: The forwarding mode as enum batadv_forw_mode.
1224 */
1225enum batadv_forw_mode
1226batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb,
1227		       unsigned short vid, int *is_routable)
1228{
1229	int ret, tt_count, ip_count, unsnoop_count, total_count;
1230	bool is_unsnoopable = false;
1231	struct ethhdr *ethhdr;
1232	int rtr_count = 0;
1233
1234	ret = batadv_mcast_forw_mode_check(bat_priv, skb, &is_unsnoopable,
1235					   is_routable);
1236	if (ret == -ENOMEM)
1237		return BATADV_FORW_NONE;
1238	else if (ret < 0)
1239		return BATADV_FORW_BCAST;
1240
1241	ethhdr = eth_hdr(skb);
1242
1243	tt_count = batadv_tt_global_hash_count(bat_priv, ethhdr->h_dest,
1244					       BATADV_NO_FLAGS);
1245	ip_count = batadv_mcast_forw_want_all_ip_count(bat_priv, ethhdr);
1246	unsnoop_count = !is_unsnoopable ? 0 :
1247			atomic_read(&bat_priv->mcast.num_want_all_unsnoopables);
1248	rtr_count = batadv_mcast_forw_rtr_count(bat_priv, *is_routable);
1249
1250	total_count = tt_count + ip_count + unsnoop_count + rtr_count;
1251
1252	if (!total_count)
1253		return BATADV_FORW_NONE;
1254	else if (unsnoop_count)
1255		return BATADV_FORW_BCAST;
1256
1257	return batadv_mcast_forw_mode_by_count(bat_priv, skb, vid, *is_routable,
1258					       total_count);
1259}
1260
1261/**
1262 * batadv_mcast_forw_send_orig() - send a multicast packet to an originator
1263 * @bat_priv: the bat priv with all the soft interface information
1264 * @skb: the multicast packet to send
1265 * @vid: the vlan identifier
1266 * @orig_node: the originator to send the packet to
1267 *
1268 * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
1269 */
1270static int batadv_mcast_forw_send_orig(struct batadv_priv *bat_priv,
1271				       struct sk_buff *skb,
1272				       unsigned short vid,
1273				       struct batadv_orig_node *orig_node)
1274{
1275	/* Avoid sending multicast-in-unicast packets to other BLA
1276	 * gateways - they already got the frame from the LAN side
1277	 * we share with them.
1278	 * TODO: Refactor to take BLA into account earlier, to avoid
1279	 * reducing the mcast_fanout count.
1280	 */
1281	if (batadv_bla_is_backbone_gw_orig(bat_priv, orig_node->orig, vid)) {
1282		dev_kfree_skb(skb);
1283		return NET_XMIT_SUCCESS;
1284	}
1285
1286	return batadv_send_skb_unicast(bat_priv, skb, BATADV_UNICAST, 0,
1287				       orig_node, vid);
1288}
1289
1290/**
1291 * batadv_mcast_forw_tt() - forwards a packet to multicast listeners
1292 * @bat_priv: the bat priv with all the soft interface information
1293 * @skb: the multicast packet to transmit
1294 * @vid: the vlan identifier
1295 *
1296 * Sends copies of a frame with multicast destination to any multicast
1297 * listener registered in the translation table. A transmission is performed
1298 * via a batman-adv unicast packet for each such destination node.
1299 *
1300 * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
1301 * otherwise.
1302 */
1303static int
1304batadv_mcast_forw_tt(struct batadv_priv *bat_priv, struct sk_buff *skb,
1305		     unsigned short vid)
1306{
1307	int ret = NET_XMIT_SUCCESS;
1308	struct sk_buff *newskb;
1309
1310	struct batadv_tt_orig_list_entry *orig_entry;
1311
1312	struct batadv_tt_global_entry *tt_global;
1313	const u8 *addr = eth_hdr(skb)->h_dest;
1314
1315	tt_global = batadv_tt_global_hash_find(bat_priv, addr, vid);
1316	if (!tt_global)
1317		goto out;
1318
1319	rcu_read_lock();
1320	hlist_for_each_entry_rcu(orig_entry, &tt_global->orig_list, list) {
1321		newskb = skb_copy(skb, GFP_ATOMIC);
1322		if (!newskb) {
1323			ret = NET_XMIT_DROP;
1324			break;
1325		}
1326
1327		batadv_mcast_forw_send_orig(bat_priv, newskb, vid,
1328					    orig_entry->orig_node);
1329	}
1330	rcu_read_unlock();
1331
1332	batadv_tt_global_entry_put(tt_global);
1333
1334out:
1335	return ret;
1336}
1337
1338/**
1339 * batadv_mcast_forw_want_all_ipv4() - forward to nodes with want-all-ipv4
1340 * @bat_priv: the bat priv with all the soft interface information
1341 * @skb: the multicast packet to transmit
1342 * @vid: the vlan identifier
1343 *
1344 * Sends copies of a frame with multicast destination to any node with a
1345 * BATADV_MCAST_WANT_ALL_IPV4 flag set. A transmission is performed via a
1346 * batman-adv unicast packet for each such destination node.
1347 *
1348 * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
1349 * otherwise.
1350 */
1351static int
1352batadv_mcast_forw_want_all_ipv4(struct batadv_priv *bat_priv,
1353				struct sk_buff *skb, unsigned short vid)
1354{
1355	struct batadv_orig_node *orig_node;
1356	int ret = NET_XMIT_SUCCESS;
1357	struct sk_buff *newskb;
1358
1359	rcu_read_lock();
1360	hlist_for_each_entry_rcu(orig_node,
1361				 &bat_priv->mcast.want_all_ipv4_list,
1362				 mcast_want_all_ipv4_node) {
1363		newskb = skb_copy(skb, GFP_ATOMIC);
1364		if (!newskb) {
1365			ret = NET_XMIT_DROP;
1366			break;
1367		}
1368
1369		batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
1370	}
1371	rcu_read_unlock();
1372	return ret;
1373}
1374
1375/**
1376 * batadv_mcast_forw_want_all_ipv6() - forward to nodes with want-all-ipv6
1377 * @bat_priv: the bat priv with all the soft interface information
1378 * @skb: The multicast packet to transmit
1379 * @vid: the vlan identifier
1380 *
1381 * Sends copies of a frame with multicast destination to any node with a
1382 * BATADV_MCAST_WANT_ALL_IPV6 flag set. A transmission is performed via a
1383 * batman-adv unicast packet for each such destination node.
1384 *
1385 * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
1386 * otherwise.
1387 */
1388static int
1389batadv_mcast_forw_want_all_ipv6(struct batadv_priv *bat_priv,
1390				struct sk_buff *skb, unsigned short vid)
1391{
1392	struct batadv_orig_node *orig_node;
1393	int ret = NET_XMIT_SUCCESS;
1394	struct sk_buff *newskb;
1395
1396	rcu_read_lock();
1397	hlist_for_each_entry_rcu(orig_node,
1398				 &bat_priv->mcast.want_all_ipv6_list,
1399				 mcast_want_all_ipv6_node) {
1400		newskb = skb_copy(skb, GFP_ATOMIC);
1401		if (!newskb) {
1402			ret = NET_XMIT_DROP;
1403			break;
1404		}
1405
1406		batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
1407	}
1408	rcu_read_unlock();
1409	return ret;
1410}
1411
1412/**
1413 * batadv_mcast_forw_want_all() - forward packet to nodes in a want-all list
1414 * @bat_priv: the bat priv with all the soft interface information
1415 * @skb: the multicast packet to transmit
1416 * @vid: the vlan identifier
1417 *
1418 * Sends copies of a frame with multicast destination to any node with a
1419 * BATADV_MCAST_WANT_ALL_IPV4 or BATADV_MCAST_WANT_ALL_IPV6 flag set. A
1420 * transmission is performed via a batman-adv unicast packet for each such
1421 * destination node.
1422 *
1423 * Return: NET_XMIT_DROP on memory allocation failure or if the protocol family
1424 * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise.
1425 */
1426static int
1427batadv_mcast_forw_want_all(struct batadv_priv *bat_priv,
1428			   struct sk_buff *skb, unsigned short vid)
1429{
1430	switch (ntohs(eth_hdr(skb)->h_proto)) {
1431	case ETH_P_IP:
1432		return batadv_mcast_forw_want_all_ipv4(bat_priv, skb, vid);
1433	case ETH_P_IPV6:
1434		return batadv_mcast_forw_want_all_ipv6(bat_priv, skb, vid);
1435	default:
1436		/* we shouldn't be here... */
1437		return NET_XMIT_DROP;
1438	}
1439}
1440
1441/**
1442 * batadv_mcast_forw_want_all_rtr4() - forward to nodes with want-all-rtr4
1443 * @bat_priv: the bat priv with all the soft interface information
1444 * @skb: the multicast packet to transmit
1445 * @vid: the vlan identifier
1446 *
1447 * Sends copies of a frame with multicast destination to any node with a
1448 * BATADV_MCAST_WANT_NO_RTR4 flag unset. A transmission is performed via a
1449 * batman-adv unicast packet for each such destination node.
1450 *
1451 * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
1452 * otherwise.
1453 */
1454static int
1455batadv_mcast_forw_want_all_rtr4(struct batadv_priv *bat_priv,
1456				struct sk_buff *skb, unsigned short vid)
1457{
1458	struct batadv_orig_node *orig_node;
1459	int ret = NET_XMIT_SUCCESS;
1460	struct sk_buff *newskb;
1461
1462	rcu_read_lock();
1463	hlist_for_each_entry_rcu(orig_node,
1464				 &bat_priv->mcast.want_all_rtr4_list,
1465				 mcast_want_all_rtr4_node) {
1466		newskb = skb_copy(skb, GFP_ATOMIC);
1467		if (!newskb) {
1468			ret = NET_XMIT_DROP;
1469			break;
1470		}
1471
1472		batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
1473	}
1474	rcu_read_unlock();
1475	return ret;
1476}
1477
1478/**
1479 * batadv_mcast_forw_want_all_rtr6() - forward to nodes with want-all-rtr6
1480 * @bat_priv: the bat priv with all the soft interface information
1481 * @skb: The multicast packet to transmit
1482 * @vid: the vlan identifier
1483 *
1484 * Sends copies of a frame with multicast destination to any node with a
1485 * BATADV_MCAST_WANT_NO_RTR6 flag unset. A transmission is performed via a
1486 * batman-adv unicast packet for each such destination node.
1487 *
1488 * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
1489 * otherwise.
1490 */
1491static int
1492batadv_mcast_forw_want_all_rtr6(struct batadv_priv *bat_priv,
1493				struct sk_buff *skb, unsigned short vid)
1494{
1495	struct batadv_orig_node *orig_node;
1496	int ret = NET_XMIT_SUCCESS;
1497	struct sk_buff *newskb;
1498
1499	rcu_read_lock();
1500	hlist_for_each_entry_rcu(orig_node,
1501				 &bat_priv->mcast.want_all_rtr6_list,
1502				 mcast_want_all_rtr6_node) {
1503		newskb = skb_copy(skb, GFP_ATOMIC);
1504		if (!newskb) {
1505			ret = NET_XMIT_DROP;
1506			break;
1507		}
1508
1509		batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
1510	}
1511	rcu_read_unlock();
1512	return ret;
1513}
1514
1515/**
1516 * batadv_mcast_forw_want_rtr() - forward packet to nodes in a want-all-rtr list
1517 * @bat_priv: the bat priv with all the soft interface information
1518 * @skb: the multicast packet to transmit
1519 * @vid: the vlan identifier
1520 *
1521 * Sends copies of a frame with multicast destination to any node with a
1522 * BATADV_MCAST_WANT_NO_RTR4 or BATADV_MCAST_WANT_NO_RTR6 flag unset. A
1523 * transmission is performed via a batman-adv unicast packet for each such
1524 * destination node.
1525 *
1526 * Return: NET_XMIT_DROP on memory allocation failure or if the protocol family
1527 * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise.
1528 */
1529static int
1530batadv_mcast_forw_want_rtr(struct batadv_priv *bat_priv,
1531			   struct sk_buff *skb, unsigned short vid)
1532{
1533	switch (ntohs(eth_hdr(skb)->h_proto)) {
1534	case ETH_P_IP:
1535		return batadv_mcast_forw_want_all_rtr4(bat_priv, skb, vid);
1536	case ETH_P_IPV6:
1537		return batadv_mcast_forw_want_all_rtr6(bat_priv, skb, vid);
1538	default:
1539		/* we shouldn't be here... */
1540		return NET_XMIT_DROP;
1541	}
1542}
1543
1544/**
1545 * batadv_mcast_forw_send() - send packet to any detected multicast recipient
1546 * @bat_priv: the bat priv with all the soft interface information
1547 * @skb: the multicast packet to transmit
1548 * @vid: the vlan identifier
1549 * @is_routable: stores whether the destination is routable
1550 *
1551 * Sends copies of a frame with multicast destination to any node that signaled
1552 * interest in it, that is either via the translation table or the according
1553 * want-all flags. A transmission is performed via a batman-adv unicast packet
1554 * for each such destination node.
1555 *
1556 * The given skb is consumed/freed.
1557 *
1558 * Return: NET_XMIT_DROP on memory allocation failure or if the protocol family
1559 * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise.
1560 */
1561int batadv_mcast_forw_send(struct batadv_priv *bat_priv, struct sk_buff *skb,
1562			   unsigned short vid, int is_routable)
1563{
1564	int ret;
1565
1566	ret = batadv_mcast_forw_tt(bat_priv, skb, vid);
1567	if (ret != NET_XMIT_SUCCESS) {
1568		kfree_skb(skb);
1569		return ret;
1570	}
1571
1572	ret = batadv_mcast_forw_want_all(bat_priv, skb, vid);
1573	if (ret != NET_XMIT_SUCCESS) {
1574		kfree_skb(skb);
1575		return ret;
1576	}
1577
1578	if (!is_routable)
1579		goto skip_mc_router;
1580
1581	ret = batadv_mcast_forw_want_rtr(bat_priv, skb, vid);
1582	if (ret != NET_XMIT_SUCCESS) {
1583		kfree_skb(skb);
1584		return ret;
1585	}
1586
1587skip_mc_router:
1588	consume_skb(skb);
1589	return ret;
1590}
1591
1592/**
1593 * batadv_mcast_want_unsnoop_update() - update unsnoop counter and list
1594 * @bat_priv: the bat priv with all the soft interface information
1595 * @orig: the orig_node which multicast state might have changed of
1596 * @mcast_flags: flags indicating the new multicast state
1597 *
1598 * If the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag of this originator,
1599 * orig, has toggled then this method updates the counter and the list
1600 * accordingly.
1601 *
1602 * Caller needs to hold orig->mcast_handler_lock.
1603 */
1604static void batadv_mcast_want_unsnoop_update(struct batadv_priv *bat_priv,
1605					     struct batadv_orig_node *orig,
1606					     u8 mcast_flags)
1607{
1608	struct hlist_node *node = &orig->mcast_want_all_unsnoopables_node;
1609	struct hlist_head *head = &bat_priv->mcast.want_all_unsnoopables_list;
1610
1611	lockdep_assert_held(&orig->mcast_handler_lock);
1612
1613	/* switched from flag unset to set */
1614	if (mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
1615	    !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES)) {
1616		atomic_inc(&bat_priv->mcast.num_want_all_unsnoopables);
1617
1618		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1619		/* flag checks above + mcast_handler_lock prevents this */
1620		WARN_ON(!hlist_unhashed(node));
1621
1622		hlist_add_head_rcu(node, head);
1623		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1624	/* switched from flag set to unset */
1625	} else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) &&
1626		   orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) {
1627		atomic_dec(&bat_priv->mcast.num_want_all_unsnoopables);
1628
1629		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1630		/* flag checks above + mcast_handler_lock prevents this */
1631		WARN_ON(hlist_unhashed(node));
1632
1633		hlist_del_init_rcu(node);
1634		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1635	}
1636}
1637
1638/**
1639 * batadv_mcast_want_ipv4_update() - update want-all-ipv4 counter and list
1640 * @bat_priv: the bat priv with all the soft interface information
1641 * @orig: the orig_node which multicast state might have changed of
1642 * @mcast_flags: flags indicating the new multicast state
1643 *
1644 * If the BATADV_MCAST_WANT_ALL_IPV4 flag of this originator, orig, has
1645 * toggled then this method updates the counter and the list accordingly.
1646 *
1647 * Caller needs to hold orig->mcast_handler_lock.
1648 */
1649static void batadv_mcast_want_ipv4_update(struct batadv_priv *bat_priv,
1650					  struct batadv_orig_node *orig,
1651					  u8 mcast_flags)
1652{
1653	struct hlist_node *node = &orig->mcast_want_all_ipv4_node;
1654	struct hlist_head *head = &bat_priv->mcast.want_all_ipv4_list;
1655
1656	lockdep_assert_held(&orig->mcast_handler_lock);
1657
1658	/* switched from flag unset to set */
1659	if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV4 &&
1660	    !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4)) {
1661		atomic_inc(&bat_priv->mcast.num_want_all_ipv4);
1662
1663		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1664		/* flag checks above + mcast_handler_lock prevents this */
1665		WARN_ON(!hlist_unhashed(node));
1666
1667		hlist_add_head_rcu(node, head);
1668		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1669	/* switched from flag set to unset */
1670	} else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) &&
1671		   orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) {
1672		atomic_dec(&bat_priv->mcast.num_want_all_ipv4);
1673
1674		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1675		/* flag checks above + mcast_handler_lock prevents this */
1676		WARN_ON(hlist_unhashed(node));
1677
1678		hlist_del_init_rcu(node);
1679		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1680	}
1681}
1682
1683/**
1684 * batadv_mcast_want_ipv6_update() - update want-all-ipv6 counter and list
1685 * @bat_priv: the bat priv with all the soft interface information
1686 * @orig: the orig_node which multicast state might have changed of
1687 * @mcast_flags: flags indicating the new multicast state
1688 *
1689 * If the BATADV_MCAST_WANT_ALL_IPV6 flag of this originator, orig, has
1690 * toggled then this method updates the counter and the list accordingly.
1691 *
1692 * Caller needs to hold orig->mcast_handler_lock.
1693 */
1694static void batadv_mcast_want_ipv6_update(struct batadv_priv *bat_priv,
1695					  struct batadv_orig_node *orig,
1696					  u8 mcast_flags)
1697{
1698	struct hlist_node *node = &orig->mcast_want_all_ipv6_node;
1699	struct hlist_head *head = &bat_priv->mcast.want_all_ipv6_list;
1700
1701	lockdep_assert_held(&orig->mcast_handler_lock);
1702
1703	/* switched from flag unset to set */
1704	if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV6 &&
1705	    !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6)) {
1706		atomic_inc(&bat_priv->mcast.num_want_all_ipv6);
1707
1708		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1709		/* flag checks above + mcast_handler_lock prevents this */
1710		WARN_ON(!hlist_unhashed(node));
1711
1712		hlist_add_head_rcu(node, head);
1713		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1714	/* switched from flag set to unset */
1715	} else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) &&
1716		   orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) {
1717		atomic_dec(&bat_priv->mcast.num_want_all_ipv6);
1718
1719		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1720		/* flag checks above + mcast_handler_lock prevents this */
1721		WARN_ON(hlist_unhashed(node));
1722
1723		hlist_del_init_rcu(node);
1724		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1725	}
1726}
1727
1728/**
1729 * batadv_mcast_want_rtr4_update() - update want-all-rtr4 counter and list
1730 * @bat_priv: the bat priv with all the soft interface information
1731 * @orig: the orig_node which multicast state might have changed of
1732 * @mcast_flags: flags indicating the new multicast state
1733 *
1734 * If the BATADV_MCAST_WANT_NO_RTR4 flag of this originator, orig, has
1735 * toggled then this method updates the counter and the list accordingly.
1736 *
1737 * Caller needs to hold orig->mcast_handler_lock.
1738 */
1739static void batadv_mcast_want_rtr4_update(struct batadv_priv *bat_priv,
1740					  struct batadv_orig_node *orig,
1741					  u8 mcast_flags)
1742{
1743	struct hlist_node *node = &orig->mcast_want_all_rtr4_node;
1744	struct hlist_head *head = &bat_priv->mcast.want_all_rtr4_list;
1745
1746	lockdep_assert_held(&orig->mcast_handler_lock);
1747
1748	/* switched from flag set to unset */
1749	if (!(mcast_flags & BATADV_MCAST_WANT_NO_RTR4) &&
1750	    orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR4) {
1751		atomic_inc(&bat_priv->mcast.num_want_all_rtr4);
1752
1753		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1754		/* flag checks above + mcast_handler_lock prevents this */
1755		WARN_ON(!hlist_unhashed(node));
1756
1757		hlist_add_head_rcu(node, head);
1758		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1759	/* switched from flag unset to set */
1760	} else if (mcast_flags & BATADV_MCAST_WANT_NO_RTR4 &&
1761		   !(orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR4)) {
1762		atomic_dec(&bat_priv->mcast.num_want_all_rtr4);
1763
1764		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1765		/* flag checks above + mcast_handler_lock prevents this */
1766		WARN_ON(hlist_unhashed(node));
1767
1768		hlist_del_init_rcu(node);
1769		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1770	}
1771}
1772
1773/**
1774 * batadv_mcast_want_rtr6_update() - update want-all-rtr6 counter and list
1775 * @bat_priv: the bat priv with all the soft interface information
1776 * @orig: the orig_node which multicast state might have changed of
1777 * @mcast_flags: flags indicating the new multicast state
1778 *
1779 * If the BATADV_MCAST_WANT_NO_RTR6 flag of this originator, orig, has
1780 * toggled then this method updates the counter and the list accordingly.
1781 *
1782 * Caller needs to hold orig->mcast_handler_lock.
1783 */
1784static void batadv_mcast_want_rtr6_update(struct batadv_priv *bat_priv,
1785					  struct batadv_orig_node *orig,
1786					  u8 mcast_flags)
1787{
1788	struct hlist_node *node = &orig->mcast_want_all_rtr6_node;
1789	struct hlist_head *head = &bat_priv->mcast.want_all_rtr6_list;
1790
1791	lockdep_assert_held(&orig->mcast_handler_lock);
1792
1793	/* switched from flag set to unset */
1794	if (!(mcast_flags & BATADV_MCAST_WANT_NO_RTR6) &&
1795	    orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR6) {
1796		atomic_inc(&bat_priv->mcast.num_want_all_rtr6);
1797
1798		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1799		/* flag checks above + mcast_handler_lock prevents this */
1800		WARN_ON(!hlist_unhashed(node));
1801
1802		hlist_add_head_rcu(node, head);
1803		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1804	/* switched from flag unset to set */
1805	} else if (mcast_flags & BATADV_MCAST_WANT_NO_RTR6 &&
1806		   !(orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR6)) {
1807		atomic_dec(&bat_priv->mcast.num_want_all_rtr6);
1808
1809		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
1810		/* flag checks above + mcast_handler_lock prevents this */
1811		WARN_ON(hlist_unhashed(node));
1812
1813		hlist_del_init_rcu(node);
1814		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
1815	}
1816}
1817
1818/**
1819 * batadv_mcast_have_mc_ptype_update() - update multicast packet type counter
1820 * @bat_priv: the bat priv with all the soft interface information
1821 * @orig: the orig_node which multicast state might have changed of
1822 * @mcast_flags: flags indicating the new multicast state
1823 *
1824 * If the BATADV_MCAST_HAVE_MC_PTYPE_CAPA flag of this originator, orig, has
1825 * toggled then this method updates the counter accordingly.
1826 */
1827static void batadv_mcast_have_mc_ptype_update(struct batadv_priv *bat_priv,
1828					      struct batadv_orig_node *orig,
1829					      u8 mcast_flags)
1830{
1831	lockdep_assert_held(&orig->mcast_handler_lock);
1832
1833	/* switched from flag set to unset */
1834	if (!(mcast_flags & BATADV_MCAST_HAVE_MC_PTYPE_CAPA) &&
1835	    orig->mcast_flags & BATADV_MCAST_HAVE_MC_PTYPE_CAPA)
1836		atomic_inc(&bat_priv->mcast.num_no_mc_ptype_capa);
1837	/* switched from flag unset to set */
1838	else if (mcast_flags & BATADV_MCAST_HAVE_MC_PTYPE_CAPA &&
1839		 !(orig->mcast_flags & BATADV_MCAST_HAVE_MC_PTYPE_CAPA))
1840		atomic_dec(&bat_priv->mcast.num_no_mc_ptype_capa);
1841}
1842
1843/**
1844 * batadv_mcast_tvlv_flags_get() - get multicast flags from an OGM TVLV
1845 * @enabled: whether the originator has multicast TVLV support enabled
1846 * @tvlv_value: tvlv buffer containing the multicast flags
1847 * @tvlv_value_len: tvlv buffer length
1848 *
1849 * Return: multicast flags for the given tvlv buffer
1850 */
1851static u8
1852batadv_mcast_tvlv_flags_get(bool enabled, void *tvlv_value, u16 tvlv_value_len)
1853{
1854	u8 mcast_flags = BATADV_NO_FLAGS;
1855
1856	if (enabled && tvlv_value && tvlv_value_len >= sizeof(mcast_flags))
1857		mcast_flags = *(u8 *)tvlv_value;
1858
1859	if (!enabled) {
1860		mcast_flags |= BATADV_MCAST_WANT_ALL_IPV4;
1861		mcast_flags |= BATADV_MCAST_WANT_ALL_IPV6;
1862	}
1863
1864	/* remove redundant flags to avoid sending duplicate packets later */
1865	if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV4)
1866		mcast_flags |= BATADV_MCAST_WANT_NO_RTR4;
1867
1868	if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV6)
1869		mcast_flags |= BATADV_MCAST_WANT_NO_RTR6;
1870
1871	return mcast_flags;
1872}
1873
1874/**
1875 * batadv_mcast_tvlv_ogm_handler() - process incoming multicast tvlv container
1876 * @bat_priv: the bat priv with all the soft interface information
1877 * @orig: the orig_node of the ogm
1878 * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
1879 * @tvlv_value: tvlv buffer containing the multicast data
1880 * @tvlv_value_len: tvlv buffer length
1881 */
1882static void batadv_mcast_tvlv_ogm_handler(struct batadv_priv *bat_priv,
1883					  struct batadv_orig_node *orig,
1884					  u8 flags,
1885					  void *tvlv_value,
1886					  u16 tvlv_value_len)
1887{
1888	bool orig_mcast_enabled = !(flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
1889	u8 mcast_flags;
1890
1891	mcast_flags = batadv_mcast_tvlv_flags_get(orig_mcast_enabled,
1892						  tvlv_value, tvlv_value_len);
1893
1894	spin_lock_bh(&orig->mcast_handler_lock);
1895
1896	if (orig_mcast_enabled &&
1897	    !test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities)) {
1898		set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities);
1899	} else if (!orig_mcast_enabled &&
1900		   test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities)) {
1901		clear_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities);
1902	}
1903
1904	set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capa_initialized);
1905
1906	batadv_mcast_want_unsnoop_update(bat_priv, orig, mcast_flags);
1907	batadv_mcast_want_ipv4_update(bat_priv, orig, mcast_flags);
1908	batadv_mcast_want_ipv6_update(bat_priv, orig, mcast_flags);
1909	batadv_mcast_want_rtr4_update(bat_priv, orig, mcast_flags);
1910	batadv_mcast_want_rtr6_update(bat_priv, orig, mcast_flags);
1911	batadv_mcast_have_mc_ptype_update(bat_priv, orig, mcast_flags);
1912
1913	orig->mcast_flags = mcast_flags;
1914	spin_unlock_bh(&orig->mcast_handler_lock);
1915}
1916
1917/**
1918 * batadv_mcast_init() - initialize the multicast optimizations structures
1919 * @bat_priv: the bat priv with all the soft interface information
1920 */
1921void batadv_mcast_init(struct batadv_priv *bat_priv)
1922{
1923	batadv_tvlv_handler_register(bat_priv, batadv_mcast_tvlv_ogm_handler,
1924				     NULL, NULL, BATADV_TVLV_MCAST, 2,
1925				     BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
1926	batadv_tvlv_handler_register(bat_priv, NULL, NULL,
1927				     batadv_mcast_forw_tracker_tvlv_handler,
1928				     BATADV_TVLV_MCAST_TRACKER, 1,
1929				     BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
1930
1931	INIT_DELAYED_WORK(&bat_priv->mcast.work, batadv_mcast_mla_update);
1932	batadv_mcast_start_timer(bat_priv);
1933}
1934
1935/**
1936 * batadv_mcast_mesh_info_put() - put multicast info into a netlink message
1937 * @msg: buffer for the message
1938 * @bat_priv: the bat priv with all the soft interface information
1939 *
1940 * Return: 0 or error code.
1941 */
1942int batadv_mcast_mesh_info_put(struct sk_buff *msg,
1943			       struct batadv_priv *bat_priv)
1944{
1945	u32 flags = bat_priv->mcast.mla_flags.tvlv_flags;
1946	u32 flags_priv = BATADV_NO_FLAGS;
1947
1948	if (bat_priv->mcast.mla_flags.bridged) {
1949		flags_priv |= BATADV_MCAST_FLAGS_BRIDGED;
1950
1951		if (bat_priv->mcast.mla_flags.querier_ipv4.exists)
1952			flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV4_EXISTS;
1953		if (bat_priv->mcast.mla_flags.querier_ipv6.exists)
1954			flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV6_EXISTS;
1955		if (bat_priv->mcast.mla_flags.querier_ipv4.shadowing)
1956			flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV4_SHADOWING;
1957		if (bat_priv->mcast.mla_flags.querier_ipv6.shadowing)
1958			flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV6_SHADOWING;
1959	}
1960
1961	if (nla_put_u32(msg, BATADV_ATTR_MCAST_FLAGS, flags) ||
1962	    nla_put_u32(msg, BATADV_ATTR_MCAST_FLAGS_PRIV, flags_priv))
1963		return -EMSGSIZE;
1964
1965	return 0;
1966}
1967
1968/**
1969 * batadv_mcast_flags_dump_entry() - dump one entry of the multicast flags table
1970 *  to a netlink socket
1971 * @msg: buffer for the message
1972 * @portid: netlink port
1973 * @cb: Control block containing additional options
1974 * @orig_node: originator to dump the multicast flags of
1975 *
1976 * Return: 0 or error code.
1977 */
1978static int
1979batadv_mcast_flags_dump_entry(struct sk_buff *msg, u32 portid,
1980			      struct netlink_callback *cb,
1981			      struct batadv_orig_node *orig_node)
1982{
1983	void *hdr;
1984
1985	hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
1986			  &batadv_netlink_family, NLM_F_MULTI,
1987			  BATADV_CMD_GET_MCAST_FLAGS);
1988	if (!hdr)
1989		return -ENOBUFS;
1990
1991	genl_dump_check_consistent(cb, hdr);
1992
1993	if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
1994		    orig_node->orig)) {
1995		genlmsg_cancel(msg, hdr);
1996		return -EMSGSIZE;
1997	}
1998
1999	if (test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
2000		     &orig_node->capabilities)) {
2001		if (nla_put_u32(msg, BATADV_ATTR_MCAST_FLAGS,
2002				orig_node->mcast_flags)) {
2003			genlmsg_cancel(msg, hdr);
2004			return -EMSGSIZE;
2005		}
2006	}
2007
2008	genlmsg_end(msg, hdr);
2009	return 0;
2010}
2011
2012/**
2013 * batadv_mcast_flags_dump_bucket() - dump one bucket of the multicast flags
2014 *  table to a netlink socket
2015 * @msg: buffer for the message
2016 * @portid: netlink port
2017 * @cb: Control block containing additional options
2018 * @hash: hash to dump
2019 * @bucket: bucket index to dump
2020 * @idx_skip: How many entries to skip
2021 *
2022 * Return: 0 or error code.
2023 */
2024static int
2025batadv_mcast_flags_dump_bucket(struct sk_buff *msg, u32 portid,
2026			       struct netlink_callback *cb,
2027			       struct batadv_hashtable *hash,
2028			       unsigned int bucket, long *idx_skip)
2029{
2030	struct batadv_orig_node *orig_node;
2031	long idx = 0;
2032
2033	spin_lock_bh(&hash->list_locks[bucket]);
2034	cb->seq = atomic_read(&hash->generation) << 1 | 1;
2035
2036	hlist_for_each_entry(orig_node, &hash->table[bucket], hash_entry) {
2037		if (!test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
2038			      &orig_node->capa_initialized))
2039			continue;
2040
2041		if (idx < *idx_skip)
2042			goto skip;
2043
2044		if (batadv_mcast_flags_dump_entry(msg, portid, cb, orig_node)) {
2045			spin_unlock_bh(&hash->list_locks[bucket]);
2046			*idx_skip = idx;
2047
2048			return -EMSGSIZE;
2049		}
2050
2051skip:
2052		idx++;
2053	}
2054	spin_unlock_bh(&hash->list_locks[bucket]);
2055
2056	return 0;
2057}
2058
2059/**
2060 * __batadv_mcast_flags_dump() - dump multicast flags table to a netlink socket
2061 * @msg: buffer for the message
2062 * @portid: netlink port
2063 * @cb: Control block containing additional options
2064 * @bat_priv: the bat priv with all the soft interface information
2065 * @bucket: current bucket to dump
2066 * @idx: index in current bucket to the next entry to dump
2067 *
2068 * Return: 0 or error code.
2069 */
2070static int
2071__batadv_mcast_flags_dump(struct sk_buff *msg, u32 portid,
2072			  struct netlink_callback *cb,
2073			  struct batadv_priv *bat_priv, long *bucket, long *idx)
2074{
2075	struct batadv_hashtable *hash = bat_priv->orig_hash;
2076	long bucket_tmp = *bucket;
2077	long idx_tmp = *idx;
2078
2079	while (bucket_tmp < hash->size) {
2080		if (batadv_mcast_flags_dump_bucket(msg, portid, cb, hash,
2081						   bucket_tmp, &idx_tmp))
2082			break;
2083
2084		bucket_tmp++;
2085		idx_tmp = 0;
2086	}
2087
2088	*bucket = bucket_tmp;
2089	*idx = idx_tmp;
2090
2091	return msg->len;
2092}
2093
2094/**
2095 * batadv_mcast_netlink_get_primary() - get primary interface from netlink
2096 *  callback
2097 * @cb: netlink callback structure
2098 * @primary_if: the primary interface pointer to return the result in
2099 *
2100 * Return: 0 or error code.
2101 */
2102static int
2103batadv_mcast_netlink_get_primary(struct netlink_callback *cb,
2104				 struct batadv_hard_iface **primary_if)
2105{
2106	struct batadv_hard_iface *hard_iface = NULL;
2107	struct net *net = sock_net(cb->skb->sk);
2108	struct net_device *soft_iface;
2109	struct batadv_priv *bat_priv;
2110	int ifindex;
2111	int ret = 0;
2112
2113	ifindex = batadv_netlink_get_ifindex(cb->nlh, BATADV_ATTR_MESH_IFINDEX);
2114	if (!ifindex)
2115		return -EINVAL;
2116
2117	soft_iface = dev_get_by_index(net, ifindex);
2118	if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
2119		ret = -ENODEV;
2120		goto out;
2121	}
2122
2123	bat_priv = netdev_priv(soft_iface);
2124
2125	hard_iface = batadv_primary_if_get_selected(bat_priv);
2126	if (!hard_iface || hard_iface->if_status != BATADV_IF_ACTIVE) {
2127		ret = -ENOENT;
2128		goto out;
2129	}
2130
2131out:
2132	dev_put(soft_iface);
2133
2134	if (!ret && primary_if)
2135		*primary_if = hard_iface;
2136	else
2137		batadv_hardif_put(hard_iface);
2138
2139	return ret;
2140}
2141
2142/**
2143 * batadv_mcast_flags_dump() - dump multicast flags table to a netlink socket
2144 * @msg: buffer for the message
2145 * @cb: callback structure containing arguments
2146 *
2147 * Return: message length.
2148 */
2149int batadv_mcast_flags_dump(struct sk_buff *msg, struct netlink_callback *cb)
2150{
2151	struct batadv_hard_iface *primary_if = NULL;
2152	int portid = NETLINK_CB(cb->skb).portid;
2153	struct batadv_priv *bat_priv;
2154	long *bucket = &cb->args[0];
2155	long *idx = &cb->args[1];
2156	int ret;
2157
2158	ret = batadv_mcast_netlink_get_primary(cb, &primary_if);
2159	if (ret)
2160		return ret;
2161
2162	bat_priv = netdev_priv(primary_if->soft_iface);
2163	ret = __batadv_mcast_flags_dump(msg, portid, cb, bat_priv, bucket, idx);
2164
2165	batadv_hardif_put(primary_if);
2166	return ret;
2167}
2168
2169/**
2170 * batadv_mcast_free() - free the multicast optimizations structures
2171 * @bat_priv: the bat priv with all the soft interface information
2172 */
2173void batadv_mcast_free(struct batadv_priv *bat_priv)
2174{
2175	cancel_delayed_work_sync(&bat_priv->mcast.work);
2176
2177	batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_MCAST, 2);
2178	batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_MCAST_TRACKER, 1);
2179	batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_MCAST, 2);
2180
2181	/* safely calling outside of worker, as worker was canceled above */
2182	batadv_mcast_mla_tt_retract(bat_priv, NULL);
2183}
2184
2185/**
2186 * batadv_mcast_purge_orig() - reset originator global mcast state modifications
2187 * @orig: the originator which is going to get purged
2188 */
2189void batadv_mcast_purge_orig(struct batadv_orig_node *orig)
2190{
2191	struct batadv_priv *bat_priv = orig->bat_priv;
2192
2193	spin_lock_bh(&orig->mcast_handler_lock);
2194
2195	batadv_mcast_want_unsnoop_update(bat_priv, orig, BATADV_NO_FLAGS);
2196	batadv_mcast_want_ipv4_update(bat_priv, orig, BATADV_NO_FLAGS);
2197	batadv_mcast_want_ipv6_update(bat_priv, orig, BATADV_NO_FLAGS);
2198	batadv_mcast_want_rtr4_update(bat_priv, orig,
2199				      BATADV_MCAST_WANT_NO_RTR4);
2200	batadv_mcast_want_rtr6_update(bat_priv, orig,
2201				      BATADV_MCAST_WANT_NO_RTR6);
2202	batadv_mcast_have_mc_ptype_update(bat_priv, orig,
2203					  BATADV_MCAST_HAVE_MC_PTYPE_CAPA);
2204
2205	spin_unlock_bh(&orig->mcast_handler_lock);
2206}
2207