xref: /linux/net/batman-adv/multicast.c (revision 06d07429858317ded2db7986113a9e0129cd599b)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) B.A.T.M.A.N. contributors:
3  *
4  * Linus Lüssing
5  */
6 
7 #include "multicast.h"
8 #include "main.h"
9 
10 #include <linux/atomic.h>
11 #include <linux/bitops.h>
12 #include <linux/bug.h>
13 #include <linux/byteorder/generic.h>
14 #include <linux/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 
63 static void batadv_mcast_mla_update(struct work_struct *work);
64 
65 /**
66  * batadv_mcast_start_timer() - schedule the multicast periodic worker
67  * @bat_priv: the bat priv with all the soft interface information
68  */
batadv_mcast_start_timer(struct batadv_priv * bat_priv)69 static void batadv_mcast_start_timer(struct batadv_priv *bat_priv)
70 {
71 	queue_delayed_work(batadv_event_workqueue, &bat_priv->mcast.work,
72 			   msecs_to_jiffies(BATADV_MCAST_WORK_PERIOD));
73 }
74 
75 /**
76  * batadv_mcast_get_bridge() - get the bridge on top of the softif if it exists
77  * @soft_iface: netdev struct of the mesh interface
78  *
79  * If the given soft interface has a bridge on top then the refcount
80  * of the according net device is increased.
81  *
82  * Return: NULL if no such bridge exists. Otherwise the net device of the
83  * bridge.
84  */
batadv_mcast_get_bridge(struct net_device * soft_iface)85 static struct net_device *batadv_mcast_get_bridge(struct net_device *soft_iface)
86 {
87 	struct net_device *upper = soft_iface;
88 
89 	rcu_read_lock();
90 	do {
91 		upper = netdev_master_upper_dev_get_rcu(upper);
92 	} while (upper && !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  */
batadv_mcast_mla_rtr_flags_softif_get_ipv4(struct net_device * dev)111 static 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)
batadv_mcast_mla_rtr_flags_softif_get_ipv6(struct net_device * dev)133 static 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
143 static inline u8
batadv_mcast_mla_rtr_flags_softif_get_ipv6(struct net_device * dev)144 batadv_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  */
batadv_mcast_mla_rtr_flags_softif_get(struct batadv_priv * bat_priv,struct net_device * bridge)165 static 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  */
batadv_mcast_mla_rtr_flags_bridge_get(struct batadv_priv * bat_priv,struct net_device * bridge)195 static 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  */
batadv_mcast_mla_rtr_flags_get(struct batadv_priv * bat_priv,struct net_device * bridge)227 static 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  */
batadv_mcast_mla_forw_flags_get(struct batadv_priv * bat_priv)247 static 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  */
276 static struct batadv_mcast_mla_flags
batadv_mcast_mla_flags_get(struct batadv_priv * bat_priv)277 batadv_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  */
batadv_mcast_mla_is_duplicate(u8 * mcast_addr,struct hlist_head * mcast_list)342 static bool batadv_mcast_mla_is_duplicate(u8 *mcast_addr,
343 					  struct hlist_head *mcast_list)
344 {
345 	struct batadv_hw_addr *mcast_entry;
346 
347 	hlist_for_each_entry(mcast_entry, mcast_list, list)
348 		if (batadv_compare_eth(mcast_entry->addr, mcast_addr))
349 			return true;
350 
351 	return false;
352 }
353 
354 /**
355  * batadv_mcast_mla_softif_get_ipv4() - get softif IPv4 multicast listeners
356  * @dev: the device to collect multicast addresses from
357  * @mcast_list: a list to put found addresses into
358  * @flags: flags indicating the new multicast state
359  *
360  * Collects multicast addresses of IPv4 multicast listeners residing
361  * on this kernel on the given soft interface, dev, in
362  * the given mcast_list. In general, multicast listeners provided by
363  * your multicast receiving applications run directly on this node.
364  *
365  * Return: -ENOMEM on memory allocation error or the number of
366  * items added to the mcast_list otherwise.
367  */
368 static int
batadv_mcast_mla_softif_get_ipv4(struct net_device * dev,struct hlist_head * mcast_list,struct batadv_mcast_mla_flags * flags)369 batadv_mcast_mla_softif_get_ipv4(struct net_device *dev,
370 				 struct hlist_head *mcast_list,
371 				 struct batadv_mcast_mla_flags *flags)
372 {
373 	struct batadv_hw_addr *new;
374 	struct in_device *in_dev;
375 	u8 mcast_addr[ETH_ALEN];
376 	struct ip_mc_list *pmc;
377 	int ret = 0;
378 
379 	if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_IPV4)
380 		return 0;
381 
382 	rcu_read_lock();
383 
384 	in_dev = __in_dev_get_rcu(dev);
385 	if (!in_dev) {
386 		rcu_read_unlock();
387 		return 0;
388 	}
389 
390 	for (pmc = rcu_dereference(in_dev->mc_list); pmc;
391 	     pmc = rcu_dereference(pmc->next_rcu)) {
392 		if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
393 		    ipv4_is_local_multicast(pmc->multiaddr))
394 			continue;
395 
396 		if (!(flags->tvlv_flags & BATADV_MCAST_WANT_NO_RTR4) &&
397 		    !ipv4_is_local_multicast(pmc->multiaddr))
398 			continue;
399 
400 		ip_eth_mc_map(pmc->multiaddr, mcast_addr);
401 
402 		if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
403 			continue;
404 
405 		new = kmalloc(sizeof(*new), GFP_ATOMIC);
406 		if (!new) {
407 			ret = -ENOMEM;
408 			break;
409 		}
410 
411 		ether_addr_copy(new->addr, mcast_addr);
412 		hlist_add_head(&new->list, mcast_list);
413 		ret++;
414 	}
415 	rcu_read_unlock();
416 
417 	return ret;
418 }
419 
420 /**
421  * batadv_mcast_mla_softif_get_ipv6() - get softif IPv6 multicast listeners
422  * @dev: the device to collect multicast addresses from
423  * @mcast_list: a list to put found addresses into
424  * @flags: flags indicating the new multicast state
425  *
426  * Collects multicast addresses of IPv6 multicast listeners residing
427  * on this kernel on the given soft interface, dev, in
428  * the given mcast_list. In general, multicast listeners provided by
429  * your multicast receiving applications run directly on this node.
430  *
431  * Return: -ENOMEM on memory allocation error or the number of
432  * items added to the mcast_list otherwise.
433  */
434 #if IS_ENABLED(CONFIG_IPV6)
435 static int
batadv_mcast_mla_softif_get_ipv6(struct net_device * dev,struct hlist_head * mcast_list,struct batadv_mcast_mla_flags * flags)436 batadv_mcast_mla_softif_get_ipv6(struct net_device *dev,
437 				 struct hlist_head *mcast_list,
438 				 struct batadv_mcast_mla_flags *flags)
439 {
440 	struct batadv_hw_addr *new;
441 	struct inet6_dev *in6_dev;
442 	u8 mcast_addr[ETH_ALEN];
443 	struct ifmcaddr6 *pmc6;
444 	int ret = 0;
445 
446 	if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_IPV6)
447 		return 0;
448 
449 	rcu_read_lock();
450 
451 	in6_dev = __in6_dev_get(dev);
452 	if (!in6_dev) {
453 		rcu_read_unlock();
454 		return 0;
455 	}
456 
457 	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
493 static inline int
batadv_mcast_mla_softif_get_ipv6(struct net_device * dev,struct hlist_head * mcast_list,struct batadv_mcast_mla_flags * flags)494 batadv_mcast_mla_softif_get_ipv6(struct net_device *dev,
495 				 struct hlist_head *mcast_list,
496 				 struct batadv_mcast_mla_flags *flags)
497 {
498 	return 0;
499 }
500 #endif
501 
502 /**
503  * batadv_mcast_mla_softif_get() - get softif multicast listeners
504  * @dev: the device to collect multicast addresses from
505  * @mcast_list: a list to put found addresses into
506  * @flags: flags indicating the new multicast state
507  *
508  * Collects multicast addresses of multicast listeners residing
509  * on this kernel on the given soft interface, dev, in
510  * the given mcast_list. In general, multicast listeners provided by
511  * your multicast receiving applications run directly on this node.
512  *
513  * If there is a bridge interface on top of dev, 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  */
521 static int
batadv_mcast_mla_softif_get(struct net_device * dev,struct hlist_head * mcast_list,struct batadv_mcast_mla_flags * flags)522 batadv_mcast_mla_softif_get(struct net_device *dev,
523 			    struct hlist_head *mcast_list,
524 			    struct batadv_mcast_mla_flags *flags)
525 {
526 	struct net_device *bridge = batadv_mcast_get_bridge(dev);
527 	int ret4, ret6 = 0;
528 
529 	if (bridge)
530 		dev = bridge;
531 
532 	ret4 = batadv_mcast_mla_softif_get_ipv4(dev, mcast_list, flags);
533 	if (ret4 < 0)
534 		goto out;
535 
536 	ret6 = batadv_mcast_mla_softif_get_ipv6(dev, mcast_list, flags);
537 	if (ret6 < 0) {
538 		ret4 = 0;
539 		goto out;
540 	}
541 
542 out:
543 	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  */
batadv_mcast_mla_br_addr_cpy(char * dst,const struct br_ip * src)560 static 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  */
batadv_mcast_mla_bridge_get(struct net_device * dev,struct hlist_head * mcast_list,struct batadv_mcast_mla_flags * flags)586 static 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 
648 out:
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  */
batadv_mcast_mla_list_free(struct hlist_head * mcast_list)663 static 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  */
batadv_mcast_mla_tt_retract(struct batadv_priv * bat_priv,struct hlist_head * mcast_list)684 static 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  */
batadv_mcast_mla_tt_add(struct batadv_priv * bat_priv,struct hlist_head * mcast_list)714 static 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  */
760 static void
batadv_mcast_querier_log(struct batadv_priv * bat_priv,char * str_proto,struct batadv_mcast_querier_state * old_state,struct batadv_mcast_querier_state * new_state)761 batadv_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  */
806 static void
batadv_mcast_bridge_log(struct batadv_priv * bat_priv,struct batadv_mcast_mla_flags * new_flags)807 batadv_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  */
batadv_mcast_flags_log(struct batadv_priv * bat_priv,u8 flags)837 static 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  */
870 static void
batadv_mcast_mla_flags_update(struct batadv_priv * bat_priv,struct batadv_mcast_mla_flags * flags)871 batadv_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  */
__batadv_mcast_mla_update(struct batadv_priv * bat_priv)903 static 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 
926 out:
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  */
batadv_mcast_mla_update(struct work_struct * work)939 static 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  */
batadv_mcast_is_report_ipv4(struct sk_buff * skb)963 static 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  */
batadv_mcast_forw_mode_check_ipv4(struct batadv_priv * bat_priv,struct sk_buff * skb,bool * is_unsnoopable,int * is_routable)992 static 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  */
batadv_mcast_is_report_ipv6(struct sk_buff * skb)1029 static 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  */
batadv_mcast_forw_mode_check_ipv6(struct batadv_priv * bat_priv,struct sk_buff * skb,bool * is_unsnoopable,int * is_routable)1056 static 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  */
batadv_mcast_forw_mode_check(struct batadv_priv * bat_priv,struct sk_buff * skb,bool * is_unsnoopable,int * is_routable)1098 static 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  */
batadv_mcast_forw_want_all_ip_count(struct batadv_priv * bat_priv,struct ethhdr * ethhdr)1135 static 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 
batadv_mcast_forw_rtr_count(struct batadv_priv * bat_priv,int protocol)1159 static 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  */
1196 static enum batadv_forw_mode
batadv_mcast_forw_mode_by_count(struct batadv_priv * bat_priv,struct sk_buff * skb,unsigned short vid,int is_routable,int count)1197 batadv_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  */
1225 enum batadv_forw_mode
batadv_mcast_forw_mode(struct batadv_priv * bat_priv,struct sk_buff * skb,unsigned short vid,int * is_routable)1226 batadv_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  */
batadv_mcast_forw_send_orig(struct batadv_priv * bat_priv,struct sk_buff * skb,unsigned short vid,struct batadv_orig_node * orig_node)1270 static 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  */
1303 static int
batadv_mcast_forw_tt(struct batadv_priv * bat_priv,struct sk_buff * skb,unsigned short vid)1304 batadv_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 
1334 out:
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  */
1351 static int
batadv_mcast_forw_want_all_ipv4(struct batadv_priv * bat_priv,struct sk_buff * skb,unsigned short vid)1352 batadv_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  */
1388 static int
batadv_mcast_forw_want_all_ipv6(struct batadv_priv * bat_priv,struct sk_buff * skb,unsigned short vid)1389 batadv_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  */
1426 static int
batadv_mcast_forw_want_all(struct batadv_priv * bat_priv,struct sk_buff * skb,unsigned short vid)1427 batadv_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  */
1454 static int
batadv_mcast_forw_want_all_rtr4(struct batadv_priv * bat_priv,struct sk_buff * skb,unsigned short vid)1455 batadv_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  */
1491 static int
batadv_mcast_forw_want_all_rtr6(struct batadv_priv * bat_priv,struct sk_buff * skb,unsigned short vid)1492 batadv_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  */
1529 static int
batadv_mcast_forw_want_rtr(struct batadv_priv * bat_priv,struct sk_buff * skb,unsigned short vid)1530 batadv_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  */
batadv_mcast_forw_send(struct batadv_priv * bat_priv,struct sk_buff * skb,unsigned short vid,int is_routable)1561 int 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 
1587 skip_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  */
batadv_mcast_want_unsnoop_update(struct batadv_priv * bat_priv,struct batadv_orig_node * orig,u8 mcast_flags)1604 static 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  */
batadv_mcast_want_ipv4_update(struct batadv_priv * bat_priv,struct batadv_orig_node * orig,u8 mcast_flags)1649 static 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  */
batadv_mcast_want_ipv6_update(struct batadv_priv * bat_priv,struct batadv_orig_node * orig,u8 mcast_flags)1694 static 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  */
batadv_mcast_want_rtr4_update(struct batadv_priv * bat_priv,struct batadv_orig_node * orig,u8 mcast_flags)1739 static 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  */
batadv_mcast_want_rtr6_update(struct batadv_priv * bat_priv,struct batadv_orig_node * orig,u8 mcast_flags)1784 static 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  */
batadv_mcast_have_mc_ptype_update(struct batadv_priv * bat_priv,struct batadv_orig_node * orig,u8 mcast_flags)1827 static 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  */
1851 static u8
batadv_mcast_tvlv_flags_get(bool enabled,void * tvlv_value,u16 tvlv_value_len)1852 batadv_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  */
batadv_mcast_tvlv_ogm_handler(struct batadv_priv * bat_priv,struct batadv_orig_node * orig,u8 flags,void * tvlv_value,u16 tvlv_value_len)1882 static 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  */
batadv_mcast_init(struct batadv_priv * bat_priv)1921 void 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  */
batadv_mcast_mesh_info_put(struct sk_buff * msg,struct batadv_priv * bat_priv)1942 int 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  */
1978 static int
batadv_mcast_flags_dump_entry(struct sk_buff * msg,u32 portid,struct netlink_callback * cb,struct batadv_orig_node * orig_node)1979 batadv_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  */
2024 static int
batadv_mcast_flags_dump_bucket(struct sk_buff * msg,u32 portid,struct netlink_callback * cb,struct batadv_hashtable * hash,unsigned int bucket,long * idx_skip)2025 batadv_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 
2051 skip:
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  */
2070 static int
__batadv_mcast_flags_dump(struct sk_buff * msg,u32 portid,struct netlink_callback * cb,struct batadv_priv * bat_priv,long * bucket,long * idx)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  */
2102 static int
batadv_mcast_netlink_get_primary(struct netlink_callback * cb,struct batadv_hard_iface ** primary_if)2103 batadv_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 
2131 out:
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  */
batadv_mcast_flags_dump(struct sk_buff * msg,struct netlink_callback * cb)2149 int 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  */
batadv_mcast_free(struct batadv_priv * bat_priv)2173 void 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  */
batadv_mcast_purge_orig(struct batadv_orig_node * orig)2189 void 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