xref: /openbmc/linux/net/ipv4/igmp.c (revision ae3473231e77a3f1909d48cd144cebe5e1d049b3)
1 /*
2  *	Linux NET3:	Internet Group Management Protocol  [IGMP]
3  *
4  *	This code implements the IGMP protocol as defined in RFC1112. There has
5  *	been a further revision of this protocol since which is now supported.
6  *
7  *	If you have trouble with this module be careful what gcc you have used,
8  *	the older version didn't come out right using gcc 2.5.8, the newer one
9  *	seems to fall out with gcc 2.6.2.
10  *
11  *	Authors:
12  *		Alan Cox <alan@lxorguk.ukuu.org.uk>
13  *
14  *	This program is free software; you can redistribute it and/or
15  *	modify it under the terms of the GNU General Public License
16  *	as published by the Free Software Foundation; either version
17  *	2 of the License, or (at your option) any later version.
18  *
19  *	Fixes:
20  *
21  *		Alan Cox	:	Added lots of __inline__ to optimise
22  *					the memory usage of all the tiny little
23  *					functions.
24  *		Alan Cox	:	Dumped the header building experiment.
25  *		Alan Cox	:	Minor tweaks ready for multicast routing
26  *					and extended IGMP protocol.
27  *		Alan Cox	:	Removed a load of inline directives. Gcc 2.5.8
28  *					writes utterly bogus code otherwise (sigh)
29  *					fixed IGMP loopback to behave in the manner
30  *					desired by mrouted, fixed the fact it has been
31  *					broken since 1.3.6 and cleaned up a few minor
32  *					points.
33  *
34  *		Chih-Jen Chang	:	Tried to revise IGMP to Version 2
35  *		Tsu-Sheng Tsao		E-mail: chihjenc@scf.usc.edu and tsusheng@scf.usc.edu
36  *					The enhancements are mainly based on Steve Deering's
37  * 					ipmulti-3.5 source code.
38  *		Chih-Jen Chang	:	Added the igmp_get_mrouter_info and
39  *		Tsu-Sheng Tsao		igmp_set_mrouter_info to keep track of
40  *					the mrouted version on that device.
41  *		Chih-Jen Chang	:	Added the max_resp_time parameter to
42  *		Tsu-Sheng Tsao		igmp_heard_query(). Using this parameter
43  *					to identify the multicast router version
44  *					and do what the IGMP version 2 specified.
45  *		Chih-Jen Chang	:	Added a timer to revert to IGMP V2 router
46  *		Tsu-Sheng Tsao		if the specified time expired.
47  *		Alan Cox	:	Stop IGMP from 0.0.0.0 being accepted.
48  *		Alan Cox	:	Use GFP_ATOMIC in the right places.
49  *		Christian Daudt :	igmp timer wasn't set for local group
50  *					memberships but was being deleted,
51  *					which caused a "del_timer() called
52  *					from %p with timer not initialized\n"
53  *					message (960131).
54  *		Christian Daudt :	removed del_timer from
55  *					igmp_timer_expire function (960205).
56  *             Christian Daudt :       igmp_heard_report now only calls
57  *                                     igmp_timer_expire if tm->running is
58  *                                     true (960216).
59  *		Malcolm Beattie :	ttl comparison wrong in igmp_rcv made
60  *					igmp_heard_query never trigger. Expiry
61  *					miscalculation fixed in igmp_heard_query
62  *					and random() made to return unsigned to
63  *					prevent negative expiry times.
64  *		Alexey Kuznetsov:	Wrong group leaving behaviour, backport
65  *					fix from pending 2.1.x patches.
66  *		Alan Cox:		Forget to enable FDDI support earlier.
67  *		Alexey Kuznetsov:	Fixed leaving groups on device down.
68  *		Alexey Kuznetsov:	Accordance to igmp-v2-06 draft.
69  *		David L Stevens:	IGMPv3 support, with help from
70  *					Vinay Kulkarni
71  */
72 
73 #include <linux/module.h>
74 #include <linux/slab.h>
75 #include <linux/uaccess.h>
76 #include <linux/types.h>
77 #include <linux/kernel.h>
78 #include <linux/jiffies.h>
79 #include <linux/string.h>
80 #include <linux/socket.h>
81 #include <linux/sockios.h>
82 #include <linux/in.h>
83 #include <linux/inet.h>
84 #include <linux/netdevice.h>
85 #include <linux/skbuff.h>
86 #include <linux/inetdevice.h>
87 #include <linux/igmp.h>
88 #include <linux/if_arp.h>
89 #include <linux/rtnetlink.h>
90 #include <linux/times.h>
91 #include <linux/pkt_sched.h>
92 
93 #include <net/net_namespace.h>
94 #include <net/arp.h>
95 #include <net/ip.h>
96 #include <net/protocol.h>
97 #include <net/route.h>
98 #include <net/sock.h>
99 #include <net/checksum.h>
100 #include <net/inet_common.h>
101 #include <linux/netfilter_ipv4.h>
102 #ifdef CONFIG_IP_MROUTE
103 #include <linux/mroute.h>
104 #endif
105 #ifdef CONFIG_PROC_FS
106 #include <linux/proc_fs.h>
107 #include <linux/seq_file.h>
108 #endif
109 
110 #ifdef CONFIG_IP_MULTICAST
111 /* Parameter names and values are taken from igmp-v2-06 draft */
112 
113 #define IGMP_V1_ROUTER_PRESENT_TIMEOUT		(400*HZ)
114 #define IGMP_V2_ROUTER_PRESENT_TIMEOUT		(400*HZ)
115 #define IGMP_V2_UNSOLICITED_REPORT_INTERVAL	(10*HZ)
116 #define IGMP_V3_UNSOLICITED_REPORT_INTERVAL	(1*HZ)
117 #define IGMP_QUERY_RESPONSE_INTERVAL		(10*HZ)
118 #define IGMP_QUERY_ROBUSTNESS_VARIABLE		2
119 
120 
121 #define IGMP_INITIAL_REPORT_DELAY		(1)
122 
123 /* IGMP_INITIAL_REPORT_DELAY is not from IGMP specs!
124  * IGMP specs require to report membership immediately after
125  * joining a group, but we delay the first report by a
126  * small interval. It seems more natural and still does not
127  * contradict to specs provided this delay is small enough.
128  */
129 
130 #define IGMP_V1_SEEN(in_dev) \
131 	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \
132 	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \
133 	 ((in_dev)->mr_v1_seen && \
134 	  time_before(jiffies, (in_dev)->mr_v1_seen)))
135 #define IGMP_V2_SEEN(in_dev) \
136 	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \
137 	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \
138 	 ((in_dev)->mr_v2_seen && \
139 	  time_before(jiffies, (in_dev)->mr_v2_seen)))
140 
141 static int unsolicited_report_interval(struct in_device *in_dev)
142 {
143 	int interval_ms, interval_jiffies;
144 
145 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
146 		interval_ms = IN_DEV_CONF_GET(
147 			in_dev,
148 			IGMPV2_UNSOLICITED_REPORT_INTERVAL);
149 	else /* v3 */
150 		interval_ms = IN_DEV_CONF_GET(
151 			in_dev,
152 			IGMPV3_UNSOLICITED_REPORT_INTERVAL);
153 
154 	interval_jiffies = msecs_to_jiffies(interval_ms);
155 
156 	/* _timer functions can't handle a delay of 0 jiffies so ensure
157 	 *  we always return a positive value.
158 	 */
159 	if (interval_jiffies <= 0)
160 		interval_jiffies = 1;
161 	return interval_jiffies;
162 }
163 
164 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im);
165 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im);
166 static void igmpv3_clear_delrec(struct in_device *in_dev);
167 static int sf_setstate(struct ip_mc_list *pmc);
168 static void sf_markstate(struct ip_mc_list *pmc);
169 #endif
170 static void ip_mc_clear_src(struct ip_mc_list *pmc);
171 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
172 			 int sfcount, __be32 *psfsrc, int delta);
173 
174 static void ip_ma_put(struct ip_mc_list *im)
175 {
176 	if (atomic_dec_and_test(&im->refcnt)) {
177 		in_dev_put(im->interface);
178 		kfree_rcu(im, rcu);
179 	}
180 }
181 
182 #define for_each_pmc_rcu(in_dev, pmc)				\
183 	for (pmc = rcu_dereference(in_dev->mc_list);		\
184 	     pmc != NULL;					\
185 	     pmc = rcu_dereference(pmc->next_rcu))
186 
187 #define for_each_pmc_rtnl(in_dev, pmc)				\
188 	for (pmc = rtnl_dereference(in_dev->mc_list);		\
189 	     pmc != NULL;					\
190 	     pmc = rtnl_dereference(pmc->next_rcu))
191 
192 #ifdef CONFIG_IP_MULTICAST
193 
194 /*
195  *	Timer management
196  */
197 
198 static void igmp_stop_timer(struct ip_mc_list *im)
199 {
200 	spin_lock_bh(&im->lock);
201 	if (del_timer(&im->timer))
202 		atomic_dec(&im->refcnt);
203 	im->tm_running = 0;
204 	im->reporter = 0;
205 	im->unsolicit_count = 0;
206 	spin_unlock_bh(&im->lock);
207 }
208 
209 /* It must be called with locked im->lock */
210 static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
211 {
212 	int tv = prandom_u32() % max_delay;
213 
214 	im->tm_running = 1;
215 	if (!mod_timer(&im->timer, jiffies+tv+2))
216 		atomic_inc(&im->refcnt);
217 }
218 
219 static void igmp_gq_start_timer(struct in_device *in_dev)
220 {
221 	int tv = prandom_u32() % in_dev->mr_maxdelay;
222 
223 	in_dev->mr_gq_running = 1;
224 	if (!mod_timer(&in_dev->mr_gq_timer, jiffies+tv+2))
225 		in_dev_hold(in_dev);
226 }
227 
228 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
229 {
230 	int tv = prandom_u32() % delay;
231 
232 	if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
233 		in_dev_hold(in_dev);
234 }
235 
236 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
237 {
238 	spin_lock_bh(&im->lock);
239 	im->unsolicit_count = 0;
240 	if (del_timer(&im->timer)) {
241 		if ((long)(im->timer.expires-jiffies) < max_delay) {
242 			add_timer(&im->timer);
243 			im->tm_running = 1;
244 			spin_unlock_bh(&im->lock);
245 			return;
246 		}
247 		atomic_dec(&im->refcnt);
248 	}
249 	igmp_start_timer(im, max_delay);
250 	spin_unlock_bh(&im->lock);
251 }
252 
253 
254 /*
255  *	Send an IGMP report.
256  */
257 
258 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
259 
260 
261 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
262 	int gdeleted, int sdeleted)
263 {
264 	switch (type) {
265 	case IGMPV3_MODE_IS_INCLUDE:
266 	case IGMPV3_MODE_IS_EXCLUDE:
267 		if (gdeleted || sdeleted)
268 			return 0;
269 		if (!(pmc->gsquery && !psf->sf_gsresp)) {
270 			if (pmc->sfmode == MCAST_INCLUDE)
271 				return 1;
272 			/* don't include if this source is excluded
273 			 * in all filters
274 			 */
275 			if (psf->sf_count[MCAST_INCLUDE])
276 				return type == IGMPV3_MODE_IS_INCLUDE;
277 			return pmc->sfcount[MCAST_EXCLUDE] ==
278 				psf->sf_count[MCAST_EXCLUDE];
279 		}
280 		return 0;
281 	case IGMPV3_CHANGE_TO_INCLUDE:
282 		if (gdeleted || sdeleted)
283 			return 0;
284 		return psf->sf_count[MCAST_INCLUDE] != 0;
285 	case IGMPV3_CHANGE_TO_EXCLUDE:
286 		if (gdeleted || sdeleted)
287 			return 0;
288 		if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
289 		    psf->sf_count[MCAST_INCLUDE])
290 			return 0;
291 		return pmc->sfcount[MCAST_EXCLUDE] ==
292 			psf->sf_count[MCAST_EXCLUDE];
293 	case IGMPV3_ALLOW_NEW_SOURCES:
294 		if (gdeleted || !psf->sf_crcount)
295 			return 0;
296 		return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
297 	case IGMPV3_BLOCK_OLD_SOURCES:
298 		if (pmc->sfmode == MCAST_INCLUDE)
299 			return gdeleted || (psf->sf_crcount && sdeleted);
300 		return psf->sf_crcount && !gdeleted && !sdeleted;
301 	}
302 	return 0;
303 }
304 
305 static int
306 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
307 {
308 	struct ip_sf_list *psf;
309 	int scount = 0;
310 
311 	for (psf = pmc->sources; psf; psf = psf->sf_next) {
312 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
313 			continue;
314 		scount++;
315 	}
316 	return scount;
317 }
318 
319 static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
320 {
321 	struct sk_buff *skb;
322 	struct rtable *rt;
323 	struct iphdr *pip;
324 	struct igmpv3_report *pig;
325 	struct net *net = dev_net(dev);
326 	struct flowi4 fl4;
327 	int hlen = LL_RESERVED_SPACE(dev);
328 	int tlen = dev->needed_tailroom;
329 	unsigned int size = mtu;
330 
331 	while (1) {
332 		skb = alloc_skb(size + hlen + tlen,
333 				GFP_ATOMIC | __GFP_NOWARN);
334 		if (skb)
335 			break;
336 		size >>= 1;
337 		if (size < 256)
338 			return NULL;
339 	}
340 	skb->priority = TC_PRIO_CONTROL;
341 
342 	rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0,
343 				   0, 0,
344 				   IPPROTO_IGMP, 0, dev->ifindex);
345 	if (IS_ERR(rt)) {
346 		kfree_skb(skb);
347 		return NULL;
348 	}
349 
350 	skb_dst_set(skb, &rt->dst);
351 	skb->dev = dev;
352 
353 	skb_reserve(skb, hlen);
354 	skb_tailroom_reserve(skb, mtu, tlen);
355 
356 	skb_reset_network_header(skb);
357 	pip = ip_hdr(skb);
358 	skb_put(skb, sizeof(struct iphdr) + 4);
359 
360 	pip->version  = 4;
361 	pip->ihl      = (sizeof(struct iphdr)+4)>>2;
362 	pip->tos      = 0xc0;
363 	pip->frag_off = htons(IP_DF);
364 	pip->ttl      = 1;
365 	pip->daddr    = fl4.daddr;
366 	pip->saddr    = fl4.saddr;
367 	pip->protocol = IPPROTO_IGMP;
368 	pip->tot_len  = 0;	/* filled in later */
369 	ip_select_ident(net, skb, NULL);
370 	((u8 *)&pip[1])[0] = IPOPT_RA;
371 	((u8 *)&pip[1])[1] = 4;
372 	((u8 *)&pip[1])[2] = 0;
373 	((u8 *)&pip[1])[3] = 0;
374 
375 	skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
376 	skb_put(skb, sizeof(*pig));
377 	pig = igmpv3_report_hdr(skb);
378 	pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
379 	pig->resv1 = 0;
380 	pig->csum = 0;
381 	pig->resv2 = 0;
382 	pig->ngrec = 0;
383 	return skb;
384 }
385 
386 static int igmpv3_sendpack(struct sk_buff *skb)
387 {
388 	struct igmphdr *pig = igmp_hdr(skb);
389 	const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
390 
391 	pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
392 
393 	return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
394 }
395 
396 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
397 {
398 	return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
399 }
400 
401 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
402 	int type, struct igmpv3_grec **ppgr)
403 {
404 	struct net_device *dev = pmc->interface->dev;
405 	struct igmpv3_report *pih;
406 	struct igmpv3_grec *pgr;
407 
408 	if (!skb)
409 		skb = igmpv3_newpack(dev, dev->mtu);
410 	if (!skb)
411 		return NULL;
412 	pgr = (struct igmpv3_grec *)skb_put(skb, sizeof(struct igmpv3_grec));
413 	pgr->grec_type = type;
414 	pgr->grec_auxwords = 0;
415 	pgr->grec_nsrcs = 0;
416 	pgr->grec_mca = pmc->multiaddr;
417 	pih = igmpv3_report_hdr(skb);
418 	pih->ngrec = htons(ntohs(pih->ngrec)+1);
419 	*ppgr = pgr;
420 	return skb;
421 }
422 
423 #define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
424 
425 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
426 	int type, int gdeleted, int sdeleted)
427 {
428 	struct net_device *dev = pmc->interface->dev;
429 	struct net *net = dev_net(dev);
430 	struct igmpv3_report *pih;
431 	struct igmpv3_grec *pgr = NULL;
432 	struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
433 	int scount, stotal, first, isquery, truncate;
434 
435 	if (pmc->multiaddr == IGMP_ALL_HOSTS)
436 		return skb;
437 	if (ipv4_is_local_multicast(pmc->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
438 		return skb;
439 
440 	isquery = type == IGMPV3_MODE_IS_INCLUDE ||
441 		  type == IGMPV3_MODE_IS_EXCLUDE;
442 	truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
443 		    type == IGMPV3_CHANGE_TO_EXCLUDE;
444 
445 	stotal = scount = 0;
446 
447 	psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
448 
449 	if (!*psf_list)
450 		goto empty_source;
451 
452 	pih = skb ? igmpv3_report_hdr(skb) : NULL;
453 
454 	/* EX and TO_EX get a fresh packet, if needed */
455 	if (truncate) {
456 		if (pih && pih->ngrec &&
457 		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
458 			if (skb)
459 				igmpv3_sendpack(skb);
460 			skb = igmpv3_newpack(dev, dev->mtu);
461 		}
462 	}
463 	first = 1;
464 	psf_prev = NULL;
465 	for (psf = *psf_list; psf; psf = psf_next) {
466 		__be32 *psrc;
467 
468 		psf_next = psf->sf_next;
469 
470 		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
471 			psf_prev = psf;
472 			continue;
473 		}
474 
475 		/* Based on RFC3376 5.1. Should not send source-list change
476 		 * records when there is a filter mode change.
477 		 */
478 		if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) ||
479 		     (!gdeleted && pmc->crcount)) &&
480 		    (type == IGMPV3_ALLOW_NEW_SOURCES ||
481 		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount)
482 			goto decrease_sf_crcount;
483 
484 		/* clear marks on query responses */
485 		if (isquery)
486 			psf->sf_gsresp = 0;
487 
488 		if (AVAILABLE(skb) < sizeof(__be32) +
489 		    first*sizeof(struct igmpv3_grec)) {
490 			if (truncate && !first)
491 				break;	 /* truncate these */
492 			if (pgr)
493 				pgr->grec_nsrcs = htons(scount);
494 			if (skb)
495 				igmpv3_sendpack(skb);
496 			skb = igmpv3_newpack(dev, dev->mtu);
497 			first = 1;
498 			scount = 0;
499 		}
500 		if (first) {
501 			skb = add_grhead(skb, pmc, type, &pgr);
502 			first = 0;
503 		}
504 		if (!skb)
505 			return NULL;
506 		psrc = (__be32 *)skb_put(skb, sizeof(__be32));
507 		*psrc = psf->sf_inaddr;
508 		scount++; stotal++;
509 		if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
510 		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
511 decrease_sf_crcount:
512 			psf->sf_crcount--;
513 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
514 				if (psf_prev)
515 					psf_prev->sf_next = psf->sf_next;
516 				else
517 					*psf_list = psf->sf_next;
518 				kfree(psf);
519 				continue;
520 			}
521 		}
522 		psf_prev = psf;
523 	}
524 
525 empty_source:
526 	if (!stotal) {
527 		if (type == IGMPV3_ALLOW_NEW_SOURCES ||
528 		    type == IGMPV3_BLOCK_OLD_SOURCES)
529 			return skb;
530 		if (pmc->crcount || isquery) {
531 			/* make sure we have room for group header */
532 			if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) {
533 				igmpv3_sendpack(skb);
534 				skb = NULL; /* add_grhead will get a new one */
535 			}
536 			skb = add_grhead(skb, pmc, type, &pgr);
537 		}
538 	}
539 	if (pgr)
540 		pgr->grec_nsrcs = htons(scount);
541 
542 	if (isquery)
543 		pmc->gsquery = 0;	/* clear query state on report */
544 	return skb;
545 }
546 
547 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
548 {
549 	struct sk_buff *skb = NULL;
550 	struct net *net = dev_net(in_dev->dev);
551 	int type;
552 
553 	if (!pmc) {
554 		rcu_read_lock();
555 		for_each_pmc_rcu(in_dev, pmc) {
556 			if (pmc->multiaddr == IGMP_ALL_HOSTS)
557 				continue;
558 			if (ipv4_is_local_multicast(pmc->multiaddr) &&
559 			     !net->ipv4.sysctl_igmp_llm_reports)
560 				continue;
561 			spin_lock_bh(&pmc->lock);
562 			if (pmc->sfcount[MCAST_EXCLUDE])
563 				type = IGMPV3_MODE_IS_EXCLUDE;
564 			else
565 				type = IGMPV3_MODE_IS_INCLUDE;
566 			skb = add_grec(skb, pmc, type, 0, 0);
567 			spin_unlock_bh(&pmc->lock);
568 		}
569 		rcu_read_unlock();
570 	} else {
571 		spin_lock_bh(&pmc->lock);
572 		if (pmc->sfcount[MCAST_EXCLUDE])
573 			type = IGMPV3_MODE_IS_EXCLUDE;
574 		else
575 			type = IGMPV3_MODE_IS_INCLUDE;
576 		skb = add_grec(skb, pmc, type, 0, 0);
577 		spin_unlock_bh(&pmc->lock);
578 	}
579 	if (!skb)
580 		return 0;
581 	return igmpv3_sendpack(skb);
582 }
583 
584 /*
585  * remove zero-count source records from a source filter list
586  */
587 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
588 {
589 	struct ip_sf_list *psf_prev, *psf_next, *psf;
590 
591 	psf_prev = NULL;
592 	for (psf = *ppsf; psf; psf = psf_next) {
593 		psf_next = psf->sf_next;
594 		if (psf->sf_crcount == 0) {
595 			if (psf_prev)
596 				psf_prev->sf_next = psf->sf_next;
597 			else
598 				*ppsf = psf->sf_next;
599 			kfree(psf);
600 		} else
601 			psf_prev = psf;
602 	}
603 }
604 
605 static void igmpv3_send_cr(struct in_device *in_dev)
606 {
607 	struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
608 	struct sk_buff *skb = NULL;
609 	int type, dtype;
610 
611 	rcu_read_lock();
612 	spin_lock_bh(&in_dev->mc_tomb_lock);
613 
614 	/* deleted MCA's */
615 	pmc_prev = NULL;
616 	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) {
617 		pmc_next = pmc->next;
618 		if (pmc->sfmode == MCAST_INCLUDE) {
619 			type = IGMPV3_BLOCK_OLD_SOURCES;
620 			dtype = IGMPV3_BLOCK_OLD_SOURCES;
621 			skb = add_grec(skb, pmc, type, 1, 0);
622 			skb = add_grec(skb, pmc, dtype, 1, 1);
623 		}
624 		if (pmc->crcount) {
625 			if (pmc->sfmode == MCAST_EXCLUDE) {
626 				type = IGMPV3_CHANGE_TO_INCLUDE;
627 				skb = add_grec(skb, pmc, type, 1, 0);
628 			}
629 			pmc->crcount--;
630 			if (pmc->crcount == 0) {
631 				igmpv3_clear_zeros(&pmc->tomb);
632 				igmpv3_clear_zeros(&pmc->sources);
633 			}
634 		}
635 		if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
636 			if (pmc_prev)
637 				pmc_prev->next = pmc_next;
638 			else
639 				in_dev->mc_tomb = pmc_next;
640 			in_dev_put(pmc->interface);
641 			kfree(pmc);
642 		} else
643 			pmc_prev = pmc;
644 	}
645 	spin_unlock_bh(&in_dev->mc_tomb_lock);
646 
647 	/* change recs */
648 	for_each_pmc_rcu(in_dev, pmc) {
649 		spin_lock_bh(&pmc->lock);
650 		if (pmc->sfcount[MCAST_EXCLUDE]) {
651 			type = IGMPV3_BLOCK_OLD_SOURCES;
652 			dtype = IGMPV3_ALLOW_NEW_SOURCES;
653 		} else {
654 			type = IGMPV3_ALLOW_NEW_SOURCES;
655 			dtype = IGMPV3_BLOCK_OLD_SOURCES;
656 		}
657 		skb = add_grec(skb, pmc, type, 0, 0);
658 		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
659 
660 		/* filter mode changes */
661 		if (pmc->crcount) {
662 			if (pmc->sfmode == MCAST_EXCLUDE)
663 				type = IGMPV3_CHANGE_TO_EXCLUDE;
664 			else
665 				type = IGMPV3_CHANGE_TO_INCLUDE;
666 			skb = add_grec(skb, pmc, type, 0, 0);
667 			pmc->crcount--;
668 		}
669 		spin_unlock_bh(&pmc->lock);
670 	}
671 	rcu_read_unlock();
672 
673 	if (!skb)
674 		return;
675 	(void) igmpv3_sendpack(skb);
676 }
677 
678 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
679 	int type)
680 {
681 	struct sk_buff *skb;
682 	struct iphdr *iph;
683 	struct igmphdr *ih;
684 	struct rtable *rt;
685 	struct net_device *dev = in_dev->dev;
686 	struct net *net = dev_net(dev);
687 	__be32	group = pmc ? pmc->multiaddr : 0;
688 	struct flowi4 fl4;
689 	__be32	dst;
690 	int hlen, tlen;
691 
692 	if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
693 		return igmpv3_send_report(in_dev, pmc);
694 
695 	if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
696 		return 0;
697 
698 	if (type == IGMP_HOST_LEAVE_MESSAGE)
699 		dst = IGMP_ALL_ROUTER;
700 	else
701 		dst = group;
702 
703 	rt = ip_route_output_ports(net, &fl4, NULL, dst, 0,
704 				   0, 0,
705 				   IPPROTO_IGMP, 0, dev->ifindex);
706 	if (IS_ERR(rt))
707 		return -1;
708 
709 	hlen = LL_RESERVED_SPACE(dev);
710 	tlen = dev->needed_tailroom;
711 	skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC);
712 	if (!skb) {
713 		ip_rt_put(rt);
714 		return -1;
715 	}
716 	skb->priority = TC_PRIO_CONTROL;
717 
718 	skb_dst_set(skb, &rt->dst);
719 
720 	skb_reserve(skb, hlen);
721 
722 	skb_reset_network_header(skb);
723 	iph = ip_hdr(skb);
724 	skb_put(skb, sizeof(struct iphdr) + 4);
725 
726 	iph->version  = 4;
727 	iph->ihl      = (sizeof(struct iphdr)+4)>>2;
728 	iph->tos      = 0xc0;
729 	iph->frag_off = htons(IP_DF);
730 	iph->ttl      = 1;
731 	iph->daddr    = dst;
732 	iph->saddr    = fl4.saddr;
733 	iph->protocol = IPPROTO_IGMP;
734 	ip_select_ident(net, skb, NULL);
735 	((u8 *)&iph[1])[0] = IPOPT_RA;
736 	((u8 *)&iph[1])[1] = 4;
737 	((u8 *)&iph[1])[2] = 0;
738 	((u8 *)&iph[1])[3] = 0;
739 
740 	ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
741 	ih->type = type;
742 	ih->code = 0;
743 	ih->csum = 0;
744 	ih->group = group;
745 	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
746 
747 	return ip_local_out(net, skb->sk, skb);
748 }
749 
750 static void igmp_gq_timer_expire(unsigned long data)
751 {
752 	struct in_device *in_dev = (struct in_device *)data;
753 
754 	in_dev->mr_gq_running = 0;
755 	igmpv3_send_report(in_dev, NULL);
756 	in_dev_put(in_dev);
757 }
758 
759 static void igmp_ifc_timer_expire(unsigned long data)
760 {
761 	struct in_device *in_dev = (struct in_device *)data;
762 
763 	igmpv3_send_cr(in_dev);
764 	if (in_dev->mr_ifc_count) {
765 		in_dev->mr_ifc_count--;
766 		igmp_ifc_start_timer(in_dev,
767 				     unsolicited_report_interval(in_dev));
768 	}
769 	in_dev_put(in_dev);
770 }
771 
772 static void igmp_ifc_event(struct in_device *in_dev)
773 {
774 	struct net *net = dev_net(in_dev->dev);
775 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
776 		return;
777 	in_dev->mr_ifc_count = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
778 	igmp_ifc_start_timer(in_dev, 1);
779 }
780 
781 
782 static void igmp_timer_expire(unsigned long data)
783 {
784 	struct ip_mc_list *im = (struct ip_mc_list *)data;
785 	struct in_device *in_dev = im->interface;
786 
787 	spin_lock(&im->lock);
788 	im->tm_running = 0;
789 
790 	if (im->unsolicit_count) {
791 		im->unsolicit_count--;
792 		igmp_start_timer(im, unsolicited_report_interval(in_dev));
793 	}
794 	im->reporter = 1;
795 	spin_unlock(&im->lock);
796 
797 	if (IGMP_V1_SEEN(in_dev))
798 		igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
799 	else if (IGMP_V2_SEEN(in_dev))
800 		igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
801 	else
802 		igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
803 
804 	ip_ma_put(im);
805 }
806 
807 /* mark EXCLUDE-mode sources */
808 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
809 {
810 	struct ip_sf_list *psf;
811 	int i, scount;
812 
813 	scount = 0;
814 	for (psf = pmc->sources; psf; psf = psf->sf_next) {
815 		if (scount == nsrcs)
816 			break;
817 		for (i = 0; i < nsrcs; i++) {
818 			/* skip inactive filters */
819 			if (psf->sf_count[MCAST_INCLUDE] ||
820 			    pmc->sfcount[MCAST_EXCLUDE] !=
821 			    psf->sf_count[MCAST_EXCLUDE])
822 				break;
823 			if (srcs[i] == psf->sf_inaddr) {
824 				scount++;
825 				break;
826 			}
827 		}
828 	}
829 	pmc->gsquery = 0;
830 	if (scount == nsrcs)	/* all sources excluded */
831 		return 0;
832 	return 1;
833 }
834 
835 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
836 {
837 	struct ip_sf_list *psf;
838 	int i, scount;
839 
840 	if (pmc->sfmode == MCAST_EXCLUDE)
841 		return igmp_xmarksources(pmc, nsrcs, srcs);
842 
843 	/* mark INCLUDE-mode sources */
844 	scount = 0;
845 	for (psf = pmc->sources; psf; psf = psf->sf_next) {
846 		if (scount == nsrcs)
847 			break;
848 		for (i = 0; i < nsrcs; i++)
849 			if (srcs[i] == psf->sf_inaddr) {
850 				psf->sf_gsresp = 1;
851 				scount++;
852 				break;
853 			}
854 	}
855 	if (!scount) {
856 		pmc->gsquery = 0;
857 		return 0;
858 	}
859 	pmc->gsquery = 1;
860 	return 1;
861 }
862 
863 /* return true if packet was dropped */
864 static bool igmp_heard_report(struct in_device *in_dev, __be32 group)
865 {
866 	struct ip_mc_list *im;
867 	struct net *net = dev_net(in_dev->dev);
868 
869 	/* Timers are only set for non-local groups */
870 
871 	if (group == IGMP_ALL_HOSTS)
872 		return false;
873 	if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
874 		return false;
875 
876 	rcu_read_lock();
877 	for_each_pmc_rcu(in_dev, im) {
878 		if (im->multiaddr == group) {
879 			igmp_stop_timer(im);
880 			break;
881 		}
882 	}
883 	rcu_read_unlock();
884 	return false;
885 }
886 
887 /* return true if packet was dropped */
888 static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
889 	int len)
890 {
891 	struct igmphdr 		*ih = igmp_hdr(skb);
892 	struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
893 	struct ip_mc_list	*im;
894 	__be32			group = ih->group;
895 	int			max_delay;
896 	int			mark = 0;
897 	struct net		*net = dev_net(in_dev->dev);
898 
899 
900 	if (len == 8) {
901 		if (ih->code == 0) {
902 			/* Alas, old v1 router presents here. */
903 
904 			max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
905 			in_dev->mr_v1_seen = jiffies +
906 				IGMP_V1_ROUTER_PRESENT_TIMEOUT;
907 			group = 0;
908 		} else {
909 			/* v2 router present */
910 			max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
911 			in_dev->mr_v2_seen = jiffies +
912 				IGMP_V2_ROUTER_PRESENT_TIMEOUT;
913 		}
914 		/* cancel the interface change timer */
915 		in_dev->mr_ifc_count = 0;
916 		if (del_timer(&in_dev->mr_ifc_timer))
917 			__in_dev_put(in_dev);
918 		/* clear deleted report items */
919 		igmpv3_clear_delrec(in_dev);
920 	} else if (len < 12) {
921 		return true;	/* ignore bogus packet; freed by caller */
922 	} else if (IGMP_V1_SEEN(in_dev)) {
923 		/* This is a v3 query with v1 queriers present */
924 		max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
925 		group = 0;
926 	} else if (IGMP_V2_SEEN(in_dev)) {
927 		/* this is a v3 query with v2 queriers present;
928 		 * Interpretation of the max_delay code is problematic here.
929 		 * A real v2 host would use ih_code directly, while v3 has a
930 		 * different encoding. We use the v3 encoding as more likely
931 		 * to be intended in a v3 query.
932 		 */
933 		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
934 		if (!max_delay)
935 			max_delay = 1;	/* can't mod w/ 0 */
936 	} else { /* v3 */
937 		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
938 			return true;
939 
940 		ih3 = igmpv3_query_hdr(skb);
941 		if (ih3->nsrcs) {
942 			if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
943 					   + ntohs(ih3->nsrcs)*sizeof(__be32)))
944 				return true;
945 			ih3 = igmpv3_query_hdr(skb);
946 		}
947 
948 		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
949 		if (!max_delay)
950 			max_delay = 1;	/* can't mod w/ 0 */
951 		in_dev->mr_maxdelay = max_delay;
952 		if (ih3->qrv)
953 			in_dev->mr_qrv = ih3->qrv;
954 		if (!group) { /* general query */
955 			if (ih3->nsrcs)
956 				return true;	/* no sources allowed */
957 			igmp_gq_start_timer(in_dev);
958 			return false;
959 		}
960 		/* mark sources to include, if group & source-specific */
961 		mark = ih3->nsrcs != 0;
962 	}
963 
964 	/*
965 	 * - Start the timers in all of our membership records
966 	 *   that the query applies to for the interface on
967 	 *   which the query arrived excl. those that belong
968 	 *   to a "local" group (224.0.0.X)
969 	 * - For timers already running check if they need to
970 	 *   be reset.
971 	 * - Use the igmp->igmp_code field as the maximum
972 	 *   delay possible
973 	 */
974 	rcu_read_lock();
975 	for_each_pmc_rcu(in_dev, im) {
976 		int changed;
977 
978 		if (group && group != im->multiaddr)
979 			continue;
980 		if (im->multiaddr == IGMP_ALL_HOSTS)
981 			continue;
982 		if (ipv4_is_local_multicast(im->multiaddr) &&
983 		    !net->ipv4.sysctl_igmp_llm_reports)
984 			continue;
985 		spin_lock_bh(&im->lock);
986 		if (im->tm_running)
987 			im->gsquery = im->gsquery && mark;
988 		else
989 			im->gsquery = mark;
990 		changed = !im->gsquery ||
991 			igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
992 		spin_unlock_bh(&im->lock);
993 		if (changed)
994 			igmp_mod_timer(im, max_delay);
995 	}
996 	rcu_read_unlock();
997 	return false;
998 }
999 
1000 /* called in rcu_read_lock() section */
1001 int igmp_rcv(struct sk_buff *skb)
1002 {
1003 	/* This basically follows the spec line by line -- see RFC1112 */
1004 	struct igmphdr *ih;
1005 	struct in_device *in_dev = __in_dev_get_rcu(skb->dev);
1006 	int len = skb->len;
1007 	bool dropped = true;
1008 
1009 	if (!in_dev)
1010 		goto drop;
1011 
1012 	if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
1013 		goto drop;
1014 
1015 	if (skb_checksum_simple_validate(skb))
1016 		goto drop;
1017 
1018 	ih = igmp_hdr(skb);
1019 	switch (ih->type) {
1020 	case IGMP_HOST_MEMBERSHIP_QUERY:
1021 		dropped = igmp_heard_query(in_dev, skb, len);
1022 		break;
1023 	case IGMP_HOST_MEMBERSHIP_REPORT:
1024 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1025 		/* Is it our report looped back? */
1026 		if (rt_is_output_route(skb_rtable(skb)))
1027 			break;
1028 		/* don't rely on MC router hearing unicast reports */
1029 		if (skb->pkt_type == PACKET_MULTICAST ||
1030 		    skb->pkt_type == PACKET_BROADCAST)
1031 			dropped = igmp_heard_report(in_dev, ih->group);
1032 		break;
1033 	case IGMP_PIM:
1034 #ifdef CONFIG_IP_PIMSM_V1
1035 		return pim_rcv_v1(skb);
1036 #endif
1037 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1038 	case IGMP_DVMRP:
1039 	case IGMP_TRACE:
1040 	case IGMP_HOST_LEAVE_MESSAGE:
1041 	case IGMP_MTRACE:
1042 	case IGMP_MTRACE_RESP:
1043 		break;
1044 	default:
1045 		break;
1046 	}
1047 
1048 drop:
1049 	if (dropped)
1050 		kfree_skb(skb);
1051 	else
1052 		consume_skb(skb);
1053 	return 0;
1054 }
1055 
1056 #endif
1057 
1058 
1059 /*
1060  *	Add a filter to a device
1061  */
1062 
1063 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1064 {
1065 	char buf[MAX_ADDR_LEN];
1066 	struct net_device *dev = in_dev->dev;
1067 
1068 	/* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1069 	   We will get multicast token leakage, when IFF_MULTICAST
1070 	   is changed. This check should be done in ndo_set_rx_mode
1071 	   routine. Something sort of:
1072 	   if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1073 	   --ANK
1074 	   */
1075 	if (arp_mc_map(addr, buf, dev, 0) == 0)
1076 		dev_mc_add(dev, buf);
1077 }
1078 
1079 /*
1080  *	Remove a filter from a device
1081  */
1082 
1083 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1084 {
1085 	char buf[MAX_ADDR_LEN];
1086 	struct net_device *dev = in_dev->dev;
1087 
1088 	if (arp_mc_map(addr, buf, dev, 0) == 0)
1089 		dev_mc_del(dev, buf);
1090 }
1091 
1092 #ifdef CONFIG_IP_MULTICAST
1093 /*
1094  * deleted ip_mc_list manipulation
1095  */
1096 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1097 {
1098 	struct ip_mc_list *pmc;
1099 	struct net *net = dev_net(in_dev->dev);
1100 
1101 	/* this is an "ip_mc_list" for convenience; only the fields below
1102 	 * are actually used. In particular, the refcnt and users are not
1103 	 * used for management of the delete list. Using the same structure
1104 	 * for deleted items allows change reports to use common code with
1105 	 * non-deleted or query-response MCA's.
1106 	 */
1107 	pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
1108 	if (!pmc)
1109 		return;
1110 	spin_lock_bh(&im->lock);
1111 	pmc->interface = im->interface;
1112 	in_dev_hold(in_dev);
1113 	pmc->multiaddr = im->multiaddr;
1114 	pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1115 	pmc->sfmode = im->sfmode;
1116 	if (pmc->sfmode == MCAST_INCLUDE) {
1117 		struct ip_sf_list *psf;
1118 
1119 		pmc->tomb = im->tomb;
1120 		pmc->sources = im->sources;
1121 		im->tomb = im->sources = NULL;
1122 		for (psf = pmc->sources; psf; psf = psf->sf_next)
1123 			psf->sf_crcount = pmc->crcount;
1124 	}
1125 	spin_unlock_bh(&im->lock);
1126 
1127 	spin_lock_bh(&in_dev->mc_tomb_lock);
1128 	pmc->next = in_dev->mc_tomb;
1129 	in_dev->mc_tomb = pmc;
1130 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1131 }
1132 
1133 /*
1134  * restore ip_mc_list deleted records
1135  */
1136 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1137 {
1138 	struct ip_mc_list *pmc, *pmc_prev;
1139 	struct ip_sf_list *psf;
1140 	struct net *net = dev_net(in_dev->dev);
1141 	__be32 multiaddr = im->multiaddr;
1142 
1143 	spin_lock_bh(&in_dev->mc_tomb_lock);
1144 	pmc_prev = NULL;
1145 	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) {
1146 		if (pmc->multiaddr == multiaddr)
1147 			break;
1148 		pmc_prev = pmc;
1149 	}
1150 	if (pmc) {
1151 		if (pmc_prev)
1152 			pmc_prev->next = pmc->next;
1153 		else
1154 			in_dev->mc_tomb = pmc->next;
1155 	}
1156 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1157 
1158 	spin_lock_bh(&im->lock);
1159 	if (pmc) {
1160 		im->interface = pmc->interface;
1161 		im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1162 		im->sfmode = pmc->sfmode;
1163 		if (pmc->sfmode == MCAST_INCLUDE) {
1164 			im->tomb = pmc->tomb;
1165 			im->sources = pmc->sources;
1166 			for (psf = im->sources; psf; psf = psf->sf_next)
1167 				psf->sf_crcount = im->crcount;
1168 		}
1169 		in_dev_put(pmc->interface);
1170 	}
1171 	spin_unlock_bh(&im->lock);
1172 }
1173 
1174 /*
1175  * flush ip_mc_list deleted records
1176  */
1177 static void igmpv3_clear_delrec(struct in_device *in_dev)
1178 {
1179 	struct ip_mc_list *pmc, *nextpmc;
1180 
1181 	spin_lock_bh(&in_dev->mc_tomb_lock);
1182 	pmc = in_dev->mc_tomb;
1183 	in_dev->mc_tomb = NULL;
1184 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1185 
1186 	for (; pmc; pmc = nextpmc) {
1187 		nextpmc = pmc->next;
1188 		ip_mc_clear_src(pmc);
1189 		in_dev_put(pmc->interface);
1190 		kfree(pmc);
1191 	}
1192 	/* clear dead sources, too */
1193 	rcu_read_lock();
1194 	for_each_pmc_rcu(in_dev, pmc) {
1195 		struct ip_sf_list *psf, *psf_next;
1196 
1197 		spin_lock_bh(&pmc->lock);
1198 		psf = pmc->tomb;
1199 		pmc->tomb = NULL;
1200 		spin_unlock_bh(&pmc->lock);
1201 		for (; psf; psf = psf_next) {
1202 			psf_next = psf->sf_next;
1203 			kfree(psf);
1204 		}
1205 	}
1206 	rcu_read_unlock();
1207 }
1208 #endif
1209 
1210 static void igmp_group_dropped(struct ip_mc_list *im)
1211 {
1212 	struct in_device *in_dev = im->interface;
1213 #ifdef CONFIG_IP_MULTICAST
1214 	struct net *net = dev_net(in_dev->dev);
1215 	int reporter;
1216 #endif
1217 
1218 	if (im->loaded) {
1219 		im->loaded = 0;
1220 		ip_mc_filter_del(in_dev, im->multiaddr);
1221 	}
1222 
1223 #ifdef CONFIG_IP_MULTICAST
1224 	if (im->multiaddr == IGMP_ALL_HOSTS)
1225 		return;
1226 	if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1227 		return;
1228 
1229 	reporter = im->reporter;
1230 	igmp_stop_timer(im);
1231 
1232 	if (!in_dev->dead) {
1233 		if (IGMP_V1_SEEN(in_dev))
1234 			return;
1235 		if (IGMP_V2_SEEN(in_dev)) {
1236 			if (reporter)
1237 				igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1238 			return;
1239 		}
1240 		/* IGMPv3 */
1241 		igmpv3_add_delrec(in_dev, im);
1242 
1243 		igmp_ifc_event(in_dev);
1244 	}
1245 #endif
1246 }
1247 
1248 static void igmp_group_added(struct ip_mc_list *im)
1249 {
1250 	struct in_device *in_dev = im->interface;
1251 #ifdef CONFIG_IP_MULTICAST
1252 	struct net *net = dev_net(in_dev->dev);
1253 #endif
1254 
1255 	if (im->loaded == 0) {
1256 		im->loaded = 1;
1257 		ip_mc_filter_add(in_dev, im->multiaddr);
1258 	}
1259 
1260 #ifdef CONFIG_IP_MULTICAST
1261 	if (im->multiaddr == IGMP_ALL_HOSTS)
1262 		return;
1263 	if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1264 		return;
1265 
1266 	if (in_dev->dead)
1267 		return;
1268 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1269 		spin_lock_bh(&im->lock);
1270 		igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY);
1271 		spin_unlock_bh(&im->lock);
1272 		return;
1273 	}
1274 	/* else, v3 */
1275 
1276 	im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1277 	igmp_ifc_event(in_dev);
1278 #endif
1279 }
1280 
1281 
1282 /*
1283  *	Multicast list managers
1284  */
1285 
1286 static u32 ip_mc_hash(const struct ip_mc_list *im)
1287 {
1288 	return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
1289 }
1290 
1291 static void ip_mc_hash_add(struct in_device *in_dev,
1292 			   struct ip_mc_list *im)
1293 {
1294 	struct ip_mc_list __rcu **mc_hash;
1295 	u32 hash;
1296 
1297 	mc_hash = rtnl_dereference(in_dev->mc_hash);
1298 	if (mc_hash) {
1299 		hash = ip_mc_hash(im);
1300 		im->next_hash = mc_hash[hash];
1301 		rcu_assign_pointer(mc_hash[hash], im);
1302 		return;
1303 	}
1304 
1305 	/* do not use a hash table for small number of items */
1306 	if (in_dev->mc_count < 4)
1307 		return;
1308 
1309 	mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
1310 			  GFP_KERNEL);
1311 	if (!mc_hash)
1312 		return;
1313 
1314 	for_each_pmc_rtnl(in_dev, im) {
1315 		hash = ip_mc_hash(im);
1316 		im->next_hash = mc_hash[hash];
1317 		RCU_INIT_POINTER(mc_hash[hash], im);
1318 	}
1319 
1320 	rcu_assign_pointer(in_dev->mc_hash, mc_hash);
1321 }
1322 
1323 static void ip_mc_hash_remove(struct in_device *in_dev,
1324 			      struct ip_mc_list *im)
1325 {
1326 	struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
1327 	struct ip_mc_list *aux;
1328 
1329 	if (!mc_hash)
1330 		return;
1331 	mc_hash += ip_mc_hash(im);
1332 	while ((aux = rtnl_dereference(*mc_hash)) != im)
1333 		mc_hash = &aux->next_hash;
1334 	*mc_hash = im->next_hash;
1335 }
1336 
1337 
1338 /*
1339  *	A socket has joined a multicast group on device dev.
1340  */
1341 
1342 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1343 {
1344 	struct ip_mc_list *im;
1345 #ifdef CONFIG_IP_MULTICAST
1346 	struct net *net = dev_net(in_dev->dev);
1347 #endif
1348 
1349 	ASSERT_RTNL();
1350 
1351 	for_each_pmc_rtnl(in_dev, im) {
1352 		if (im->multiaddr == addr) {
1353 			im->users++;
1354 			ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1355 			goto out;
1356 		}
1357 	}
1358 
1359 	im = kzalloc(sizeof(*im), GFP_KERNEL);
1360 	if (!im)
1361 		goto out;
1362 
1363 	im->users = 1;
1364 	im->interface = in_dev;
1365 	in_dev_hold(in_dev);
1366 	im->multiaddr = addr;
1367 	/* initial mode is (EX, empty) */
1368 	im->sfmode = MCAST_EXCLUDE;
1369 	im->sfcount[MCAST_EXCLUDE] = 1;
1370 	atomic_set(&im->refcnt, 1);
1371 	spin_lock_init(&im->lock);
1372 #ifdef CONFIG_IP_MULTICAST
1373 	setup_timer(&im->timer, igmp_timer_expire, (unsigned long)im);
1374 	im->unsolicit_count = net->ipv4.sysctl_igmp_qrv;
1375 #endif
1376 
1377 	im->next_rcu = in_dev->mc_list;
1378 	in_dev->mc_count++;
1379 	rcu_assign_pointer(in_dev->mc_list, im);
1380 
1381 	ip_mc_hash_add(in_dev, im);
1382 
1383 #ifdef CONFIG_IP_MULTICAST
1384 	igmpv3_del_delrec(in_dev, im);
1385 #endif
1386 	igmp_group_added(im);
1387 	if (!in_dev->dead)
1388 		ip_rt_multicast_event(in_dev);
1389 out:
1390 	return;
1391 }
1392 EXPORT_SYMBOL(ip_mc_inc_group);
1393 
1394 static int ip_mc_check_iphdr(struct sk_buff *skb)
1395 {
1396 	const struct iphdr *iph;
1397 	unsigned int len;
1398 	unsigned int offset = skb_network_offset(skb) + sizeof(*iph);
1399 
1400 	if (!pskb_may_pull(skb, offset))
1401 		return -EINVAL;
1402 
1403 	iph = ip_hdr(skb);
1404 
1405 	if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph))
1406 		return -EINVAL;
1407 
1408 	offset += ip_hdrlen(skb) - sizeof(*iph);
1409 
1410 	if (!pskb_may_pull(skb, offset))
1411 		return -EINVAL;
1412 
1413 	iph = ip_hdr(skb);
1414 
1415 	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1416 		return -EINVAL;
1417 
1418 	len = skb_network_offset(skb) + ntohs(iph->tot_len);
1419 	if (skb->len < len || len < offset)
1420 		return -EINVAL;
1421 
1422 	skb_set_transport_header(skb, offset);
1423 
1424 	return 0;
1425 }
1426 
1427 static int ip_mc_check_igmp_reportv3(struct sk_buff *skb)
1428 {
1429 	unsigned int len = skb_transport_offset(skb);
1430 
1431 	len += sizeof(struct igmpv3_report);
1432 
1433 	return pskb_may_pull(skb, len) ? 0 : -EINVAL;
1434 }
1435 
1436 static int ip_mc_check_igmp_query(struct sk_buff *skb)
1437 {
1438 	unsigned int len = skb_transport_offset(skb);
1439 
1440 	len += sizeof(struct igmphdr);
1441 	if (skb->len < len)
1442 		return -EINVAL;
1443 
1444 	/* IGMPv{1,2}? */
1445 	if (skb->len != len) {
1446 		/* or IGMPv3? */
1447 		len += sizeof(struct igmpv3_query) - sizeof(struct igmphdr);
1448 		if (skb->len < len || !pskb_may_pull(skb, len))
1449 			return -EINVAL;
1450 	}
1451 
1452 	/* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1453 	 * all-systems destination addresses (224.0.0.1) for general queries
1454 	 */
1455 	if (!igmp_hdr(skb)->group &&
1456 	    ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP))
1457 		return -EINVAL;
1458 
1459 	return 0;
1460 }
1461 
1462 static int ip_mc_check_igmp_msg(struct sk_buff *skb)
1463 {
1464 	switch (igmp_hdr(skb)->type) {
1465 	case IGMP_HOST_LEAVE_MESSAGE:
1466 	case IGMP_HOST_MEMBERSHIP_REPORT:
1467 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1468 		/* fall through */
1469 		return 0;
1470 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1471 		return ip_mc_check_igmp_reportv3(skb);
1472 	case IGMP_HOST_MEMBERSHIP_QUERY:
1473 		return ip_mc_check_igmp_query(skb);
1474 	default:
1475 		return -ENOMSG;
1476 	}
1477 }
1478 
1479 static inline __sum16 ip_mc_validate_checksum(struct sk_buff *skb)
1480 {
1481 	return skb_checksum_simple_validate(skb);
1482 }
1483 
1484 static int __ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
1485 
1486 {
1487 	struct sk_buff *skb_chk;
1488 	unsigned int transport_len;
1489 	unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr);
1490 	int ret = -EINVAL;
1491 
1492 	transport_len = ntohs(ip_hdr(skb)->tot_len) - ip_hdrlen(skb);
1493 
1494 	skb_chk = skb_checksum_trimmed(skb, transport_len,
1495 				       ip_mc_validate_checksum);
1496 	if (!skb_chk)
1497 		goto err;
1498 
1499 	if (!pskb_may_pull(skb_chk, len))
1500 		goto err;
1501 
1502 	ret = ip_mc_check_igmp_msg(skb_chk);
1503 	if (ret)
1504 		goto err;
1505 
1506 	if (skb_trimmed)
1507 		*skb_trimmed = skb_chk;
1508 	/* free now unneeded clone */
1509 	else if (skb_chk != skb)
1510 		kfree_skb(skb_chk);
1511 
1512 	ret = 0;
1513 
1514 err:
1515 	if (ret && skb_chk && skb_chk != skb)
1516 		kfree_skb(skb_chk);
1517 
1518 	return ret;
1519 }
1520 
1521 /**
1522  * ip_mc_check_igmp - checks whether this is a sane IGMP packet
1523  * @skb: the skb to validate
1524  * @skb_trimmed: to store an skb pointer trimmed to IPv4 packet tail (optional)
1525  *
1526  * Checks whether an IPv4 packet is a valid IGMP packet. If so sets
1527  * skb transport header accordingly and returns zero.
1528  *
1529  * -EINVAL: A broken packet was detected, i.e. it violates some internet
1530  *  standard
1531  * -ENOMSG: IP header validation succeeded but it is not an IGMP packet.
1532  * -ENOMEM: A memory allocation failure happened.
1533  *
1534  * Optionally, an skb pointer might be provided via skb_trimmed (or set it
1535  * to NULL): After parsing an IGMP packet successfully it will point to
1536  * an skb which has its tail aligned to the IP packet end. This might
1537  * either be the originally provided skb or a trimmed, cloned version if
1538  * the skb frame had data beyond the IP packet. A cloned skb allows us
1539  * to leave the original skb and its full frame unchanged (which might be
1540  * desirable for layer 2 frame jugglers).
1541  *
1542  * Caller needs to set the skb network header and free any returned skb if it
1543  * differs from the provided skb.
1544  */
1545 int ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
1546 {
1547 	int ret = ip_mc_check_iphdr(skb);
1548 
1549 	if (ret < 0)
1550 		return ret;
1551 
1552 	if (ip_hdr(skb)->protocol != IPPROTO_IGMP)
1553 		return -ENOMSG;
1554 
1555 	return __ip_mc_check_igmp(skb, skb_trimmed);
1556 }
1557 EXPORT_SYMBOL(ip_mc_check_igmp);
1558 
1559 /*
1560  *	Resend IGMP JOIN report; used by netdev notifier.
1561  */
1562 static void ip_mc_rejoin_groups(struct in_device *in_dev)
1563 {
1564 #ifdef CONFIG_IP_MULTICAST
1565 	struct ip_mc_list *im;
1566 	int type;
1567 	struct net *net = dev_net(in_dev->dev);
1568 
1569 	ASSERT_RTNL();
1570 
1571 	for_each_pmc_rtnl(in_dev, im) {
1572 		if (im->multiaddr == IGMP_ALL_HOSTS)
1573 			continue;
1574 		if (ipv4_is_local_multicast(im->multiaddr) &&
1575 		    !net->ipv4.sysctl_igmp_llm_reports)
1576 			continue;
1577 
1578 		/* a failover is happening and switches
1579 		 * must be notified immediately
1580 		 */
1581 		if (IGMP_V1_SEEN(in_dev))
1582 			type = IGMP_HOST_MEMBERSHIP_REPORT;
1583 		else if (IGMP_V2_SEEN(in_dev))
1584 			type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1585 		else
1586 			type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1587 		igmp_send_report(in_dev, im, type);
1588 	}
1589 #endif
1590 }
1591 
1592 /*
1593  *	A socket has left a multicast group on device dev
1594  */
1595 
1596 void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
1597 {
1598 	struct ip_mc_list *i;
1599 	struct ip_mc_list __rcu **ip;
1600 
1601 	ASSERT_RTNL();
1602 
1603 	for (ip = &in_dev->mc_list;
1604 	     (i = rtnl_dereference(*ip)) != NULL;
1605 	     ip = &i->next_rcu) {
1606 		if (i->multiaddr == addr) {
1607 			if (--i->users == 0) {
1608 				ip_mc_hash_remove(in_dev, i);
1609 				*ip = i->next_rcu;
1610 				in_dev->mc_count--;
1611 				igmp_group_dropped(i);
1612 				ip_mc_clear_src(i);
1613 
1614 				if (!in_dev->dead)
1615 					ip_rt_multicast_event(in_dev);
1616 
1617 				ip_ma_put(i);
1618 				return;
1619 			}
1620 			break;
1621 		}
1622 	}
1623 }
1624 EXPORT_SYMBOL(ip_mc_dec_group);
1625 
1626 /* Device changing type */
1627 
1628 void ip_mc_unmap(struct in_device *in_dev)
1629 {
1630 	struct ip_mc_list *pmc;
1631 
1632 	ASSERT_RTNL();
1633 
1634 	for_each_pmc_rtnl(in_dev, pmc)
1635 		igmp_group_dropped(pmc);
1636 }
1637 
1638 void ip_mc_remap(struct in_device *in_dev)
1639 {
1640 	struct ip_mc_list *pmc;
1641 
1642 	ASSERT_RTNL();
1643 
1644 	for_each_pmc_rtnl(in_dev, pmc) {
1645 #ifdef CONFIG_IP_MULTICAST
1646 		igmpv3_del_delrec(in_dev, pmc);
1647 #endif
1648 		igmp_group_added(pmc);
1649 	}
1650 }
1651 
1652 /* Device going down */
1653 
1654 void ip_mc_down(struct in_device *in_dev)
1655 {
1656 	struct ip_mc_list *pmc;
1657 
1658 	ASSERT_RTNL();
1659 
1660 	for_each_pmc_rtnl(in_dev, pmc)
1661 		igmp_group_dropped(pmc);
1662 
1663 #ifdef CONFIG_IP_MULTICAST
1664 	in_dev->mr_ifc_count = 0;
1665 	if (del_timer(&in_dev->mr_ifc_timer))
1666 		__in_dev_put(in_dev);
1667 	in_dev->mr_gq_running = 0;
1668 	if (del_timer(&in_dev->mr_gq_timer))
1669 		__in_dev_put(in_dev);
1670 #endif
1671 
1672 	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1673 }
1674 
1675 void ip_mc_init_dev(struct in_device *in_dev)
1676 {
1677 #ifdef CONFIG_IP_MULTICAST
1678 	struct net *net = dev_net(in_dev->dev);
1679 #endif
1680 	ASSERT_RTNL();
1681 
1682 #ifdef CONFIG_IP_MULTICAST
1683 	setup_timer(&in_dev->mr_gq_timer, igmp_gq_timer_expire,
1684 			(unsigned long)in_dev);
1685 	setup_timer(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire,
1686 			(unsigned long)in_dev);
1687 	in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1688 #endif
1689 
1690 	spin_lock_init(&in_dev->mc_tomb_lock);
1691 }
1692 
1693 /* Device going up */
1694 
1695 void ip_mc_up(struct in_device *in_dev)
1696 {
1697 	struct ip_mc_list *pmc;
1698 #ifdef CONFIG_IP_MULTICAST
1699 	struct net *net = dev_net(in_dev->dev);
1700 #endif
1701 
1702 	ASSERT_RTNL();
1703 
1704 #ifdef CONFIG_IP_MULTICAST
1705 	in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1706 #endif
1707 	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1708 
1709 	for_each_pmc_rtnl(in_dev, pmc) {
1710 #ifdef CONFIG_IP_MULTICAST
1711 		igmpv3_del_delrec(in_dev, pmc);
1712 #endif
1713 		igmp_group_added(pmc);
1714 	}
1715 }
1716 
1717 /*
1718  *	Device is about to be destroyed: clean up.
1719  */
1720 
1721 void ip_mc_destroy_dev(struct in_device *in_dev)
1722 {
1723 	struct ip_mc_list *i;
1724 
1725 	ASSERT_RTNL();
1726 
1727 	/* Deactivate timers */
1728 	ip_mc_down(in_dev);
1729 #ifdef CONFIG_IP_MULTICAST
1730 	igmpv3_clear_delrec(in_dev);
1731 #endif
1732 
1733 	while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1734 		in_dev->mc_list = i->next_rcu;
1735 		in_dev->mc_count--;
1736 		ip_ma_put(i);
1737 	}
1738 }
1739 
1740 /* RTNL is locked */
1741 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1742 {
1743 	struct net_device *dev = NULL;
1744 	struct in_device *idev = NULL;
1745 
1746 	if (imr->imr_ifindex) {
1747 		idev = inetdev_by_index(net, imr->imr_ifindex);
1748 		return idev;
1749 	}
1750 	if (imr->imr_address.s_addr) {
1751 		dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1752 		if (!dev)
1753 			return NULL;
1754 	}
1755 
1756 	if (!dev) {
1757 		struct rtable *rt = ip_route_output(net,
1758 						    imr->imr_multiaddr.s_addr,
1759 						    0, 0, 0);
1760 		if (!IS_ERR(rt)) {
1761 			dev = rt->dst.dev;
1762 			ip_rt_put(rt);
1763 		}
1764 	}
1765 	if (dev) {
1766 		imr->imr_ifindex = dev->ifindex;
1767 		idev = __in_dev_get_rtnl(dev);
1768 	}
1769 	return idev;
1770 }
1771 
1772 /*
1773  *	Join a socket to a group
1774  */
1775 
1776 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1777 	__be32 *psfsrc)
1778 {
1779 	struct ip_sf_list *psf, *psf_prev;
1780 	int rv = 0;
1781 
1782 	psf_prev = NULL;
1783 	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1784 		if (psf->sf_inaddr == *psfsrc)
1785 			break;
1786 		psf_prev = psf;
1787 	}
1788 	if (!psf || psf->sf_count[sfmode] == 0) {
1789 		/* source filter not found, or count wrong =>  bug */
1790 		return -ESRCH;
1791 	}
1792 	psf->sf_count[sfmode]--;
1793 	if (psf->sf_count[sfmode] == 0) {
1794 		ip_rt_multicast_event(pmc->interface);
1795 	}
1796 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1797 #ifdef CONFIG_IP_MULTICAST
1798 		struct in_device *in_dev = pmc->interface;
1799 		struct net *net = dev_net(in_dev->dev);
1800 #endif
1801 
1802 		/* no more filters for this source */
1803 		if (psf_prev)
1804 			psf_prev->sf_next = psf->sf_next;
1805 		else
1806 			pmc->sources = psf->sf_next;
1807 #ifdef CONFIG_IP_MULTICAST
1808 		if (psf->sf_oldin &&
1809 		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1810 			psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1811 			psf->sf_next = pmc->tomb;
1812 			pmc->tomb = psf;
1813 			rv = 1;
1814 		} else
1815 #endif
1816 			kfree(psf);
1817 	}
1818 	return rv;
1819 }
1820 
1821 #ifndef CONFIG_IP_MULTICAST
1822 #define igmp_ifc_event(x)	do { } while (0)
1823 #endif
1824 
1825 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1826 			 int sfcount, __be32 *psfsrc, int delta)
1827 {
1828 	struct ip_mc_list *pmc;
1829 	int	changerec = 0;
1830 	int	i, err;
1831 
1832 	if (!in_dev)
1833 		return -ENODEV;
1834 	rcu_read_lock();
1835 	for_each_pmc_rcu(in_dev, pmc) {
1836 		if (*pmca == pmc->multiaddr)
1837 			break;
1838 	}
1839 	if (!pmc) {
1840 		/* MCA not found?? bug */
1841 		rcu_read_unlock();
1842 		return -ESRCH;
1843 	}
1844 	spin_lock_bh(&pmc->lock);
1845 	rcu_read_unlock();
1846 #ifdef CONFIG_IP_MULTICAST
1847 	sf_markstate(pmc);
1848 #endif
1849 	if (!delta) {
1850 		err = -EINVAL;
1851 		if (!pmc->sfcount[sfmode])
1852 			goto out_unlock;
1853 		pmc->sfcount[sfmode]--;
1854 	}
1855 	err = 0;
1856 	for (i = 0; i < sfcount; i++) {
1857 		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1858 
1859 		changerec |= rv > 0;
1860 		if (!err && rv < 0)
1861 			err = rv;
1862 	}
1863 	if (pmc->sfmode == MCAST_EXCLUDE &&
1864 	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1865 	    pmc->sfcount[MCAST_INCLUDE]) {
1866 #ifdef CONFIG_IP_MULTICAST
1867 		struct ip_sf_list *psf;
1868 		struct net *net = dev_net(in_dev->dev);
1869 #endif
1870 
1871 		/* filter mode change */
1872 		pmc->sfmode = MCAST_INCLUDE;
1873 #ifdef CONFIG_IP_MULTICAST
1874 		pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1875 		in_dev->mr_ifc_count = pmc->crcount;
1876 		for (psf = pmc->sources; psf; psf = psf->sf_next)
1877 			psf->sf_crcount = 0;
1878 		igmp_ifc_event(pmc->interface);
1879 	} else if (sf_setstate(pmc) || changerec) {
1880 		igmp_ifc_event(pmc->interface);
1881 #endif
1882 	}
1883 out_unlock:
1884 	spin_unlock_bh(&pmc->lock);
1885 	return err;
1886 }
1887 
1888 /*
1889  * Add multicast single-source filter to the interface list
1890  */
1891 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1892 	__be32 *psfsrc)
1893 {
1894 	struct ip_sf_list *psf, *psf_prev;
1895 
1896 	psf_prev = NULL;
1897 	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1898 		if (psf->sf_inaddr == *psfsrc)
1899 			break;
1900 		psf_prev = psf;
1901 	}
1902 	if (!psf) {
1903 		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1904 		if (!psf)
1905 			return -ENOBUFS;
1906 		psf->sf_inaddr = *psfsrc;
1907 		if (psf_prev) {
1908 			psf_prev->sf_next = psf;
1909 		} else
1910 			pmc->sources = psf;
1911 	}
1912 	psf->sf_count[sfmode]++;
1913 	if (psf->sf_count[sfmode] == 1) {
1914 		ip_rt_multicast_event(pmc->interface);
1915 	}
1916 	return 0;
1917 }
1918 
1919 #ifdef CONFIG_IP_MULTICAST
1920 static void sf_markstate(struct ip_mc_list *pmc)
1921 {
1922 	struct ip_sf_list *psf;
1923 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1924 
1925 	for (psf = pmc->sources; psf; psf = psf->sf_next)
1926 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1927 			psf->sf_oldin = mca_xcount ==
1928 				psf->sf_count[MCAST_EXCLUDE] &&
1929 				!psf->sf_count[MCAST_INCLUDE];
1930 		} else
1931 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1932 }
1933 
1934 static int sf_setstate(struct ip_mc_list *pmc)
1935 {
1936 	struct ip_sf_list *psf, *dpsf;
1937 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1938 	int qrv = pmc->interface->mr_qrv;
1939 	int new_in, rv;
1940 
1941 	rv = 0;
1942 	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1943 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1944 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1945 				!psf->sf_count[MCAST_INCLUDE];
1946 		} else
1947 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1948 		if (new_in) {
1949 			if (!psf->sf_oldin) {
1950 				struct ip_sf_list *prev = NULL;
1951 
1952 				for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) {
1953 					if (dpsf->sf_inaddr == psf->sf_inaddr)
1954 						break;
1955 					prev = dpsf;
1956 				}
1957 				if (dpsf) {
1958 					if (prev)
1959 						prev->sf_next = dpsf->sf_next;
1960 					else
1961 						pmc->tomb = dpsf->sf_next;
1962 					kfree(dpsf);
1963 				}
1964 				psf->sf_crcount = qrv;
1965 				rv++;
1966 			}
1967 		} else if (psf->sf_oldin) {
1968 
1969 			psf->sf_crcount = 0;
1970 			/*
1971 			 * add or update "delete" records if an active filter
1972 			 * is now inactive
1973 			 */
1974 			for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next)
1975 				if (dpsf->sf_inaddr == psf->sf_inaddr)
1976 					break;
1977 			if (!dpsf) {
1978 				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
1979 				if (!dpsf)
1980 					continue;
1981 				*dpsf = *psf;
1982 				/* pmc->lock held by callers */
1983 				dpsf->sf_next = pmc->tomb;
1984 				pmc->tomb = dpsf;
1985 			}
1986 			dpsf->sf_crcount = qrv;
1987 			rv++;
1988 		}
1989 	}
1990 	return rv;
1991 }
1992 #endif
1993 
1994 /*
1995  * Add multicast source filter list to the interface list
1996  */
1997 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1998 			 int sfcount, __be32 *psfsrc, int delta)
1999 {
2000 	struct ip_mc_list *pmc;
2001 	int	isexclude;
2002 	int	i, err;
2003 
2004 	if (!in_dev)
2005 		return -ENODEV;
2006 	rcu_read_lock();
2007 	for_each_pmc_rcu(in_dev, pmc) {
2008 		if (*pmca == pmc->multiaddr)
2009 			break;
2010 	}
2011 	if (!pmc) {
2012 		/* MCA not found?? bug */
2013 		rcu_read_unlock();
2014 		return -ESRCH;
2015 	}
2016 	spin_lock_bh(&pmc->lock);
2017 	rcu_read_unlock();
2018 
2019 #ifdef CONFIG_IP_MULTICAST
2020 	sf_markstate(pmc);
2021 #endif
2022 	isexclude = pmc->sfmode == MCAST_EXCLUDE;
2023 	if (!delta)
2024 		pmc->sfcount[sfmode]++;
2025 	err = 0;
2026 	for (i = 0; i < sfcount; i++) {
2027 		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2028 		if (err)
2029 			break;
2030 	}
2031 	if (err) {
2032 		int j;
2033 
2034 		if (!delta)
2035 			pmc->sfcount[sfmode]--;
2036 		for (j = 0; j < i; j++)
2037 			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2038 	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
2039 #ifdef CONFIG_IP_MULTICAST
2040 		struct ip_sf_list *psf;
2041 		struct net *net = dev_net(pmc->interface->dev);
2042 		in_dev = pmc->interface;
2043 #endif
2044 
2045 		/* filter mode change */
2046 		if (pmc->sfcount[MCAST_EXCLUDE])
2047 			pmc->sfmode = MCAST_EXCLUDE;
2048 		else if (pmc->sfcount[MCAST_INCLUDE])
2049 			pmc->sfmode = MCAST_INCLUDE;
2050 #ifdef CONFIG_IP_MULTICAST
2051 		/* else no filters; keep old mode for reports */
2052 
2053 		pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
2054 		in_dev->mr_ifc_count = pmc->crcount;
2055 		for (psf = pmc->sources; psf; psf = psf->sf_next)
2056 			psf->sf_crcount = 0;
2057 		igmp_ifc_event(in_dev);
2058 	} else if (sf_setstate(pmc)) {
2059 		igmp_ifc_event(in_dev);
2060 #endif
2061 	}
2062 	spin_unlock_bh(&pmc->lock);
2063 	return err;
2064 }
2065 
2066 static void ip_mc_clear_src(struct ip_mc_list *pmc)
2067 {
2068 	struct ip_sf_list *psf, *nextpsf;
2069 
2070 	for (psf = pmc->tomb; psf; psf = nextpsf) {
2071 		nextpsf = psf->sf_next;
2072 		kfree(psf);
2073 	}
2074 	pmc->tomb = NULL;
2075 	for (psf = pmc->sources; psf; psf = nextpsf) {
2076 		nextpsf = psf->sf_next;
2077 		kfree(psf);
2078 	}
2079 	pmc->sources = NULL;
2080 	pmc->sfmode = MCAST_EXCLUDE;
2081 	pmc->sfcount[MCAST_INCLUDE] = 0;
2082 	pmc->sfcount[MCAST_EXCLUDE] = 1;
2083 }
2084 
2085 /* Join a multicast group
2086  */
2087 
2088 int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
2089 {
2090 	__be32 addr = imr->imr_multiaddr.s_addr;
2091 	struct ip_mc_socklist *iml, *i;
2092 	struct in_device *in_dev;
2093 	struct inet_sock *inet = inet_sk(sk);
2094 	struct net *net = sock_net(sk);
2095 	int ifindex;
2096 	int count = 0;
2097 	int err;
2098 
2099 	ASSERT_RTNL();
2100 
2101 	if (!ipv4_is_multicast(addr))
2102 		return -EINVAL;
2103 
2104 	in_dev = ip_mc_find_dev(net, imr);
2105 
2106 	if (!in_dev) {
2107 		err = -ENODEV;
2108 		goto done;
2109 	}
2110 
2111 	err = -EADDRINUSE;
2112 	ifindex = imr->imr_ifindex;
2113 	for_each_pmc_rtnl(inet, i) {
2114 		if (i->multi.imr_multiaddr.s_addr == addr &&
2115 		    i->multi.imr_ifindex == ifindex)
2116 			goto done;
2117 		count++;
2118 	}
2119 	err = -ENOBUFS;
2120 	if (count >= net->ipv4.sysctl_igmp_max_memberships)
2121 		goto done;
2122 	iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
2123 	if (!iml)
2124 		goto done;
2125 
2126 	memcpy(&iml->multi, imr, sizeof(*imr));
2127 	iml->next_rcu = inet->mc_list;
2128 	iml->sflist = NULL;
2129 	iml->sfmode = MCAST_EXCLUDE;
2130 	rcu_assign_pointer(inet->mc_list, iml);
2131 	ip_mc_inc_group(in_dev, addr);
2132 	err = 0;
2133 done:
2134 	return err;
2135 }
2136 EXPORT_SYMBOL(ip_mc_join_group);
2137 
2138 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
2139 			   struct in_device *in_dev)
2140 {
2141 	struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
2142 	int err;
2143 
2144 	if (!psf) {
2145 		/* any-source empty exclude case */
2146 		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2147 			iml->sfmode, 0, NULL, 0);
2148 	}
2149 	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2150 			iml->sfmode, psf->sl_count, psf->sl_addr, 0);
2151 	RCU_INIT_POINTER(iml->sflist, NULL);
2152 	/* decrease mem now to avoid the memleak warning */
2153 	atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc);
2154 	kfree_rcu(psf, rcu);
2155 	return err;
2156 }
2157 
2158 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
2159 {
2160 	struct inet_sock *inet = inet_sk(sk);
2161 	struct ip_mc_socklist *iml;
2162 	struct ip_mc_socklist __rcu **imlp;
2163 	struct in_device *in_dev;
2164 	struct net *net = sock_net(sk);
2165 	__be32 group = imr->imr_multiaddr.s_addr;
2166 	u32 ifindex;
2167 	int ret = -EADDRNOTAVAIL;
2168 
2169 	ASSERT_RTNL();
2170 
2171 	in_dev = ip_mc_find_dev(net, imr);
2172 	if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) {
2173 		ret = -ENODEV;
2174 		goto out;
2175 	}
2176 	ifindex = imr->imr_ifindex;
2177 	for (imlp = &inet->mc_list;
2178 	     (iml = rtnl_dereference(*imlp)) != NULL;
2179 	     imlp = &iml->next_rcu) {
2180 		if (iml->multi.imr_multiaddr.s_addr != group)
2181 			continue;
2182 		if (ifindex) {
2183 			if (iml->multi.imr_ifindex != ifindex)
2184 				continue;
2185 		} else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
2186 				iml->multi.imr_address.s_addr)
2187 			continue;
2188 
2189 		(void) ip_mc_leave_src(sk, iml, in_dev);
2190 
2191 		*imlp = iml->next_rcu;
2192 
2193 		if (in_dev)
2194 			ip_mc_dec_group(in_dev, group);
2195 
2196 		/* decrease mem now to avoid the memleak warning */
2197 		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2198 		kfree_rcu(iml, rcu);
2199 		return 0;
2200 	}
2201 out:
2202 	return ret;
2203 }
2204 EXPORT_SYMBOL(ip_mc_leave_group);
2205 
2206 int ip_mc_source(int add, int omode, struct sock *sk, struct
2207 	ip_mreq_source *mreqs, int ifindex)
2208 {
2209 	int err;
2210 	struct ip_mreqn imr;
2211 	__be32 addr = mreqs->imr_multiaddr;
2212 	struct ip_mc_socklist *pmc;
2213 	struct in_device *in_dev = NULL;
2214 	struct inet_sock *inet = inet_sk(sk);
2215 	struct ip_sf_socklist *psl;
2216 	struct net *net = sock_net(sk);
2217 	int leavegroup = 0;
2218 	int i, j, rv;
2219 
2220 	if (!ipv4_is_multicast(addr))
2221 		return -EINVAL;
2222 
2223 	ASSERT_RTNL();
2224 
2225 	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
2226 	imr.imr_address.s_addr = mreqs->imr_interface;
2227 	imr.imr_ifindex = ifindex;
2228 	in_dev = ip_mc_find_dev(net, &imr);
2229 
2230 	if (!in_dev) {
2231 		err = -ENODEV;
2232 		goto done;
2233 	}
2234 	err = -EADDRNOTAVAIL;
2235 
2236 	for_each_pmc_rtnl(inet, pmc) {
2237 		if ((pmc->multi.imr_multiaddr.s_addr ==
2238 		     imr.imr_multiaddr.s_addr) &&
2239 		    (pmc->multi.imr_ifindex == imr.imr_ifindex))
2240 			break;
2241 	}
2242 	if (!pmc) {		/* must have a prior join */
2243 		err = -EINVAL;
2244 		goto done;
2245 	}
2246 	/* if a source filter was set, must be the same mode as before */
2247 	if (pmc->sflist) {
2248 		if (pmc->sfmode != omode) {
2249 			err = -EINVAL;
2250 			goto done;
2251 		}
2252 	} else if (pmc->sfmode != omode) {
2253 		/* allow mode switches for empty-set filters */
2254 		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
2255 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
2256 			NULL, 0);
2257 		pmc->sfmode = omode;
2258 	}
2259 
2260 	psl = rtnl_dereference(pmc->sflist);
2261 	if (!add) {
2262 		if (!psl)
2263 			goto done;	/* err = -EADDRNOTAVAIL */
2264 		rv = !0;
2265 		for (i = 0; i < psl->sl_count; i++) {
2266 			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2267 				sizeof(__be32));
2268 			if (rv == 0)
2269 				break;
2270 		}
2271 		if (rv)		/* source not found */
2272 			goto done;	/* err = -EADDRNOTAVAIL */
2273 
2274 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2275 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
2276 			leavegroup = 1;
2277 			goto done;
2278 		}
2279 
2280 		/* update the interface filter */
2281 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2282 			&mreqs->imr_sourceaddr, 1);
2283 
2284 		for (j = i+1; j < psl->sl_count; j++)
2285 			psl->sl_addr[j-1] = psl->sl_addr[j];
2286 		psl->sl_count--;
2287 		err = 0;
2288 		goto done;
2289 	}
2290 	/* else, add a new source to the filter */
2291 
2292 	if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) {
2293 		err = -ENOBUFS;
2294 		goto done;
2295 	}
2296 	if (!psl || psl->sl_count == psl->sl_max) {
2297 		struct ip_sf_socklist *newpsl;
2298 		int count = IP_SFBLOCK;
2299 
2300 		if (psl)
2301 			count += psl->sl_max;
2302 		newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
2303 		if (!newpsl) {
2304 			err = -ENOBUFS;
2305 			goto done;
2306 		}
2307 		newpsl->sl_max = count;
2308 		newpsl->sl_count = count - IP_SFBLOCK;
2309 		if (psl) {
2310 			for (i = 0; i < psl->sl_count; i++)
2311 				newpsl->sl_addr[i] = psl->sl_addr[i];
2312 			/* decrease mem now to avoid the memleak warning */
2313 			atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2314 			kfree_rcu(psl, rcu);
2315 		}
2316 		rcu_assign_pointer(pmc->sflist, newpsl);
2317 		psl = newpsl;
2318 	}
2319 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
2320 	for (i = 0; i < psl->sl_count; i++) {
2321 		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2322 			sizeof(__be32));
2323 		if (rv == 0)
2324 			break;
2325 	}
2326 	if (rv == 0)		/* address already there is an error */
2327 		goto done;
2328 	for (j = psl->sl_count-1; j >= i; j--)
2329 		psl->sl_addr[j+1] = psl->sl_addr[j];
2330 	psl->sl_addr[i] = mreqs->imr_sourceaddr;
2331 	psl->sl_count++;
2332 	err = 0;
2333 	/* update the interface list */
2334 	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2335 		&mreqs->imr_sourceaddr, 1);
2336 done:
2337 	if (leavegroup)
2338 		err = ip_mc_leave_group(sk, &imr);
2339 	return err;
2340 }
2341 
2342 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2343 {
2344 	int err = 0;
2345 	struct ip_mreqn	imr;
2346 	__be32 addr = msf->imsf_multiaddr;
2347 	struct ip_mc_socklist *pmc;
2348 	struct in_device *in_dev;
2349 	struct inet_sock *inet = inet_sk(sk);
2350 	struct ip_sf_socklist *newpsl, *psl;
2351 	struct net *net = sock_net(sk);
2352 	int leavegroup = 0;
2353 
2354 	if (!ipv4_is_multicast(addr))
2355 		return -EINVAL;
2356 	if (msf->imsf_fmode != MCAST_INCLUDE &&
2357 	    msf->imsf_fmode != MCAST_EXCLUDE)
2358 		return -EINVAL;
2359 
2360 	ASSERT_RTNL();
2361 
2362 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2363 	imr.imr_address.s_addr = msf->imsf_interface;
2364 	imr.imr_ifindex = ifindex;
2365 	in_dev = ip_mc_find_dev(net, &imr);
2366 
2367 	if (!in_dev) {
2368 		err = -ENODEV;
2369 		goto done;
2370 	}
2371 
2372 	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2373 	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2374 		leavegroup = 1;
2375 		goto done;
2376 	}
2377 
2378 	for_each_pmc_rtnl(inet, pmc) {
2379 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2380 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2381 			break;
2382 	}
2383 	if (!pmc) {		/* must have a prior join */
2384 		err = -EINVAL;
2385 		goto done;
2386 	}
2387 	if (msf->imsf_numsrc) {
2388 		newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2389 							   GFP_KERNEL);
2390 		if (!newpsl) {
2391 			err = -ENOBUFS;
2392 			goto done;
2393 		}
2394 		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2395 		memcpy(newpsl->sl_addr, msf->imsf_slist,
2396 			msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2397 		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2398 			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2399 		if (err) {
2400 			sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2401 			goto done;
2402 		}
2403 	} else {
2404 		newpsl = NULL;
2405 		(void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2406 				     msf->imsf_fmode, 0, NULL, 0);
2407 	}
2408 	psl = rtnl_dereference(pmc->sflist);
2409 	if (psl) {
2410 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2411 			psl->sl_count, psl->sl_addr, 0);
2412 		/* decrease mem now to avoid the memleak warning */
2413 		atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2414 		kfree_rcu(psl, rcu);
2415 	} else
2416 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2417 			0, NULL, 0);
2418 	rcu_assign_pointer(pmc->sflist, newpsl);
2419 	pmc->sfmode = msf->imsf_fmode;
2420 	err = 0;
2421 done:
2422 	if (leavegroup)
2423 		err = ip_mc_leave_group(sk, &imr);
2424 	return err;
2425 }
2426 
2427 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2428 	struct ip_msfilter __user *optval, int __user *optlen)
2429 {
2430 	int err, len, count, copycount;
2431 	struct ip_mreqn	imr;
2432 	__be32 addr = msf->imsf_multiaddr;
2433 	struct ip_mc_socklist *pmc;
2434 	struct in_device *in_dev;
2435 	struct inet_sock *inet = inet_sk(sk);
2436 	struct ip_sf_socklist *psl;
2437 	struct net *net = sock_net(sk);
2438 
2439 	ASSERT_RTNL();
2440 
2441 	if (!ipv4_is_multicast(addr))
2442 		return -EINVAL;
2443 
2444 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2445 	imr.imr_address.s_addr = msf->imsf_interface;
2446 	imr.imr_ifindex = 0;
2447 	in_dev = ip_mc_find_dev(net, &imr);
2448 
2449 	if (!in_dev) {
2450 		err = -ENODEV;
2451 		goto done;
2452 	}
2453 	err = -EADDRNOTAVAIL;
2454 
2455 	for_each_pmc_rtnl(inet, pmc) {
2456 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2457 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2458 			break;
2459 	}
2460 	if (!pmc)		/* must have a prior join */
2461 		goto done;
2462 	msf->imsf_fmode = pmc->sfmode;
2463 	psl = rtnl_dereference(pmc->sflist);
2464 	if (!psl) {
2465 		len = 0;
2466 		count = 0;
2467 	} else {
2468 		count = psl->sl_count;
2469 	}
2470 	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2471 	len = copycount * sizeof(psl->sl_addr[0]);
2472 	msf->imsf_numsrc = count;
2473 	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2474 	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2475 		return -EFAULT;
2476 	}
2477 	if (len &&
2478 	    copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2479 		return -EFAULT;
2480 	return 0;
2481 done:
2482 	return err;
2483 }
2484 
2485 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2486 	struct group_filter __user *optval, int __user *optlen)
2487 {
2488 	int err, i, count, copycount;
2489 	struct sockaddr_in *psin;
2490 	__be32 addr;
2491 	struct ip_mc_socklist *pmc;
2492 	struct inet_sock *inet = inet_sk(sk);
2493 	struct ip_sf_socklist *psl;
2494 
2495 	ASSERT_RTNL();
2496 
2497 	psin = (struct sockaddr_in *)&gsf->gf_group;
2498 	if (psin->sin_family != AF_INET)
2499 		return -EINVAL;
2500 	addr = psin->sin_addr.s_addr;
2501 	if (!ipv4_is_multicast(addr))
2502 		return -EINVAL;
2503 
2504 	err = -EADDRNOTAVAIL;
2505 
2506 	for_each_pmc_rtnl(inet, pmc) {
2507 		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2508 		    pmc->multi.imr_ifindex == gsf->gf_interface)
2509 			break;
2510 	}
2511 	if (!pmc)		/* must have a prior join */
2512 		goto done;
2513 	gsf->gf_fmode = pmc->sfmode;
2514 	psl = rtnl_dereference(pmc->sflist);
2515 	count = psl ? psl->sl_count : 0;
2516 	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2517 	gsf->gf_numsrc = count;
2518 	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2519 	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2520 		return -EFAULT;
2521 	}
2522 	for (i = 0; i < copycount; i++) {
2523 		struct sockaddr_storage ss;
2524 
2525 		psin = (struct sockaddr_in *)&ss;
2526 		memset(&ss, 0, sizeof(ss));
2527 		psin->sin_family = AF_INET;
2528 		psin->sin_addr.s_addr = psl->sl_addr[i];
2529 		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2530 			return -EFAULT;
2531 	}
2532 	return 0;
2533 done:
2534 	return err;
2535 }
2536 
2537 /*
2538  * check if a multicast source filter allows delivery for a given <src,dst,intf>
2539  */
2540 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif)
2541 {
2542 	struct inet_sock *inet = inet_sk(sk);
2543 	struct ip_mc_socklist *pmc;
2544 	struct ip_sf_socklist *psl;
2545 	int i;
2546 	int ret;
2547 
2548 	ret = 1;
2549 	if (!ipv4_is_multicast(loc_addr))
2550 		goto out;
2551 
2552 	rcu_read_lock();
2553 	for_each_pmc_rcu(inet, pmc) {
2554 		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2555 		    pmc->multi.imr_ifindex == dif)
2556 			break;
2557 	}
2558 	ret = inet->mc_all;
2559 	if (!pmc)
2560 		goto unlock;
2561 	psl = rcu_dereference(pmc->sflist);
2562 	ret = (pmc->sfmode == MCAST_EXCLUDE);
2563 	if (!psl)
2564 		goto unlock;
2565 
2566 	for (i = 0; i < psl->sl_count; i++) {
2567 		if (psl->sl_addr[i] == rmt_addr)
2568 			break;
2569 	}
2570 	ret = 0;
2571 	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2572 		goto unlock;
2573 	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2574 		goto unlock;
2575 	ret = 1;
2576 unlock:
2577 	rcu_read_unlock();
2578 out:
2579 	return ret;
2580 }
2581 
2582 /*
2583  *	A socket is closing.
2584  */
2585 
2586 void ip_mc_drop_socket(struct sock *sk)
2587 {
2588 	struct inet_sock *inet = inet_sk(sk);
2589 	struct ip_mc_socklist *iml;
2590 	struct net *net = sock_net(sk);
2591 
2592 	if (!inet->mc_list)
2593 		return;
2594 
2595 	rtnl_lock();
2596 	while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2597 		struct in_device *in_dev;
2598 
2599 		inet->mc_list = iml->next_rcu;
2600 		in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2601 		(void) ip_mc_leave_src(sk, iml, in_dev);
2602 		if (in_dev)
2603 			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2604 		/* decrease mem now to avoid the memleak warning */
2605 		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2606 		kfree_rcu(iml, rcu);
2607 	}
2608 	rtnl_unlock();
2609 }
2610 
2611 /* called with rcu_read_lock() */
2612 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto)
2613 {
2614 	struct ip_mc_list *im;
2615 	struct ip_mc_list __rcu **mc_hash;
2616 	struct ip_sf_list *psf;
2617 	int rv = 0;
2618 
2619 	mc_hash = rcu_dereference(in_dev->mc_hash);
2620 	if (mc_hash) {
2621 		u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
2622 
2623 		for (im = rcu_dereference(mc_hash[hash]);
2624 		     im != NULL;
2625 		     im = rcu_dereference(im->next_hash)) {
2626 			if (im->multiaddr == mc_addr)
2627 				break;
2628 		}
2629 	} else {
2630 		for_each_pmc_rcu(in_dev, im) {
2631 			if (im->multiaddr == mc_addr)
2632 				break;
2633 		}
2634 	}
2635 	if (im && proto == IPPROTO_IGMP) {
2636 		rv = 1;
2637 	} else if (im) {
2638 		if (src_addr) {
2639 			for (psf = im->sources; psf; psf = psf->sf_next) {
2640 				if (psf->sf_inaddr == src_addr)
2641 					break;
2642 			}
2643 			if (psf)
2644 				rv = psf->sf_count[MCAST_INCLUDE] ||
2645 					psf->sf_count[MCAST_EXCLUDE] !=
2646 					im->sfcount[MCAST_EXCLUDE];
2647 			else
2648 				rv = im->sfcount[MCAST_EXCLUDE] != 0;
2649 		} else
2650 			rv = 1; /* unspecified source; tentatively allow */
2651 	}
2652 	return rv;
2653 }
2654 
2655 #if defined(CONFIG_PROC_FS)
2656 struct igmp_mc_iter_state {
2657 	struct seq_net_private p;
2658 	struct net_device *dev;
2659 	struct in_device *in_dev;
2660 };
2661 
2662 #define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2663 
2664 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2665 {
2666 	struct net *net = seq_file_net(seq);
2667 	struct ip_mc_list *im = NULL;
2668 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2669 
2670 	state->in_dev = NULL;
2671 	for_each_netdev_rcu(net, state->dev) {
2672 		struct in_device *in_dev;
2673 
2674 		in_dev = __in_dev_get_rcu(state->dev);
2675 		if (!in_dev)
2676 			continue;
2677 		im = rcu_dereference(in_dev->mc_list);
2678 		if (im) {
2679 			state->in_dev = in_dev;
2680 			break;
2681 		}
2682 	}
2683 	return im;
2684 }
2685 
2686 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2687 {
2688 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2689 
2690 	im = rcu_dereference(im->next_rcu);
2691 	while (!im) {
2692 		state->dev = next_net_device_rcu(state->dev);
2693 		if (!state->dev) {
2694 			state->in_dev = NULL;
2695 			break;
2696 		}
2697 		state->in_dev = __in_dev_get_rcu(state->dev);
2698 		if (!state->in_dev)
2699 			continue;
2700 		im = rcu_dereference(state->in_dev->mc_list);
2701 	}
2702 	return im;
2703 }
2704 
2705 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2706 {
2707 	struct ip_mc_list *im = igmp_mc_get_first(seq);
2708 	if (im)
2709 		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2710 			--pos;
2711 	return pos ? NULL : im;
2712 }
2713 
2714 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2715 	__acquires(rcu)
2716 {
2717 	rcu_read_lock();
2718 	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2719 }
2720 
2721 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2722 {
2723 	struct ip_mc_list *im;
2724 	if (v == SEQ_START_TOKEN)
2725 		im = igmp_mc_get_first(seq);
2726 	else
2727 		im = igmp_mc_get_next(seq, v);
2728 	++*pos;
2729 	return im;
2730 }
2731 
2732 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2733 	__releases(rcu)
2734 {
2735 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2736 
2737 	state->in_dev = NULL;
2738 	state->dev = NULL;
2739 	rcu_read_unlock();
2740 }
2741 
2742 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2743 {
2744 	if (v == SEQ_START_TOKEN)
2745 		seq_puts(seq,
2746 			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2747 	else {
2748 		struct ip_mc_list *im = (struct ip_mc_list *)v;
2749 		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2750 		char   *querier;
2751 		long delta;
2752 
2753 #ifdef CONFIG_IP_MULTICAST
2754 		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2755 			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2756 			  "V3";
2757 #else
2758 		querier = "NONE";
2759 #endif
2760 
2761 		if (rcu_access_pointer(state->in_dev->mc_list) == im) {
2762 			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2763 				   state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2764 		}
2765 
2766 		delta = im->timer.expires - jiffies;
2767 		seq_printf(seq,
2768 			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2769 			   im->multiaddr, im->users,
2770 			   im->tm_running,
2771 			   im->tm_running ? jiffies_delta_to_clock_t(delta) : 0,
2772 			   im->reporter);
2773 	}
2774 	return 0;
2775 }
2776 
2777 static const struct seq_operations igmp_mc_seq_ops = {
2778 	.start	=	igmp_mc_seq_start,
2779 	.next	=	igmp_mc_seq_next,
2780 	.stop	=	igmp_mc_seq_stop,
2781 	.show	=	igmp_mc_seq_show,
2782 };
2783 
2784 static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2785 {
2786 	return seq_open_net(inode, file, &igmp_mc_seq_ops,
2787 			sizeof(struct igmp_mc_iter_state));
2788 }
2789 
2790 static const struct file_operations igmp_mc_seq_fops = {
2791 	.owner		=	THIS_MODULE,
2792 	.open		=	igmp_mc_seq_open,
2793 	.read		=	seq_read,
2794 	.llseek		=	seq_lseek,
2795 	.release	=	seq_release_net,
2796 };
2797 
2798 struct igmp_mcf_iter_state {
2799 	struct seq_net_private p;
2800 	struct net_device *dev;
2801 	struct in_device *idev;
2802 	struct ip_mc_list *im;
2803 };
2804 
2805 #define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2806 
2807 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2808 {
2809 	struct net *net = seq_file_net(seq);
2810 	struct ip_sf_list *psf = NULL;
2811 	struct ip_mc_list *im = NULL;
2812 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2813 
2814 	state->idev = NULL;
2815 	state->im = NULL;
2816 	for_each_netdev_rcu(net, state->dev) {
2817 		struct in_device *idev;
2818 		idev = __in_dev_get_rcu(state->dev);
2819 		if (unlikely(!idev))
2820 			continue;
2821 		im = rcu_dereference(idev->mc_list);
2822 		if (likely(im)) {
2823 			spin_lock_bh(&im->lock);
2824 			psf = im->sources;
2825 			if (likely(psf)) {
2826 				state->im = im;
2827 				state->idev = idev;
2828 				break;
2829 			}
2830 			spin_unlock_bh(&im->lock);
2831 		}
2832 	}
2833 	return psf;
2834 }
2835 
2836 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2837 {
2838 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2839 
2840 	psf = psf->sf_next;
2841 	while (!psf) {
2842 		spin_unlock_bh(&state->im->lock);
2843 		state->im = state->im->next;
2844 		while (!state->im) {
2845 			state->dev = next_net_device_rcu(state->dev);
2846 			if (!state->dev) {
2847 				state->idev = NULL;
2848 				goto out;
2849 			}
2850 			state->idev = __in_dev_get_rcu(state->dev);
2851 			if (!state->idev)
2852 				continue;
2853 			state->im = rcu_dereference(state->idev->mc_list);
2854 		}
2855 		if (!state->im)
2856 			break;
2857 		spin_lock_bh(&state->im->lock);
2858 		psf = state->im->sources;
2859 	}
2860 out:
2861 	return psf;
2862 }
2863 
2864 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2865 {
2866 	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2867 	if (psf)
2868 		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2869 			--pos;
2870 	return pos ? NULL : psf;
2871 }
2872 
2873 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2874 	__acquires(rcu)
2875 {
2876 	rcu_read_lock();
2877 	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2878 }
2879 
2880 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2881 {
2882 	struct ip_sf_list *psf;
2883 	if (v == SEQ_START_TOKEN)
2884 		psf = igmp_mcf_get_first(seq);
2885 	else
2886 		psf = igmp_mcf_get_next(seq, v);
2887 	++*pos;
2888 	return psf;
2889 }
2890 
2891 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2892 	__releases(rcu)
2893 {
2894 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2895 	if (likely(state->im)) {
2896 		spin_unlock_bh(&state->im->lock);
2897 		state->im = NULL;
2898 	}
2899 	state->idev = NULL;
2900 	state->dev = NULL;
2901 	rcu_read_unlock();
2902 }
2903 
2904 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2905 {
2906 	struct ip_sf_list *psf = (struct ip_sf_list *)v;
2907 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2908 
2909 	if (v == SEQ_START_TOKEN) {
2910 		seq_puts(seq, "Idx Device        MCA        SRC    INC    EXC\n");
2911 	} else {
2912 		seq_printf(seq,
2913 			   "%3d %6.6s 0x%08x "
2914 			   "0x%08x %6lu %6lu\n",
2915 			   state->dev->ifindex, state->dev->name,
2916 			   ntohl(state->im->multiaddr),
2917 			   ntohl(psf->sf_inaddr),
2918 			   psf->sf_count[MCAST_INCLUDE],
2919 			   psf->sf_count[MCAST_EXCLUDE]);
2920 	}
2921 	return 0;
2922 }
2923 
2924 static const struct seq_operations igmp_mcf_seq_ops = {
2925 	.start	=	igmp_mcf_seq_start,
2926 	.next	=	igmp_mcf_seq_next,
2927 	.stop	=	igmp_mcf_seq_stop,
2928 	.show	=	igmp_mcf_seq_show,
2929 };
2930 
2931 static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2932 {
2933 	return seq_open_net(inode, file, &igmp_mcf_seq_ops,
2934 			sizeof(struct igmp_mcf_iter_state));
2935 }
2936 
2937 static const struct file_operations igmp_mcf_seq_fops = {
2938 	.owner		=	THIS_MODULE,
2939 	.open		=	igmp_mcf_seq_open,
2940 	.read		=	seq_read,
2941 	.llseek		=	seq_lseek,
2942 	.release	=	seq_release_net,
2943 };
2944 
2945 static int __net_init igmp_net_init(struct net *net)
2946 {
2947 	struct proc_dir_entry *pde;
2948 	int err;
2949 
2950 	pde = proc_create("igmp", S_IRUGO, net->proc_net, &igmp_mc_seq_fops);
2951 	if (!pde)
2952 		goto out_igmp;
2953 	pde = proc_create("mcfilter", S_IRUGO, net->proc_net,
2954 			  &igmp_mcf_seq_fops);
2955 	if (!pde)
2956 		goto out_mcfilter;
2957 	err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET,
2958 				   SOCK_DGRAM, 0, net);
2959 	if (err < 0) {
2960 		pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n",
2961 		       err);
2962 		goto out_sock;
2963 	}
2964 
2965 	/* Sysctl initialization */
2966 	net->ipv4.sysctl_igmp_max_memberships = 20;
2967 	net->ipv4.sysctl_igmp_max_msf = 10;
2968 	/* IGMP reports for link-local multicast groups are enabled by default */
2969 	net->ipv4.sysctl_igmp_llm_reports = 1;
2970 	net->ipv4.sysctl_igmp_qrv = 2;
2971 	return 0;
2972 
2973 out_sock:
2974 	remove_proc_entry("mcfilter", net->proc_net);
2975 out_mcfilter:
2976 	remove_proc_entry("igmp", net->proc_net);
2977 out_igmp:
2978 	return -ENOMEM;
2979 }
2980 
2981 static void __net_exit igmp_net_exit(struct net *net)
2982 {
2983 	remove_proc_entry("mcfilter", net->proc_net);
2984 	remove_proc_entry("igmp", net->proc_net);
2985 	inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk);
2986 }
2987 
2988 static struct pernet_operations igmp_net_ops = {
2989 	.init = igmp_net_init,
2990 	.exit = igmp_net_exit,
2991 };
2992 #endif
2993 
2994 static int igmp_netdev_event(struct notifier_block *this,
2995 			     unsigned long event, void *ptr)
2996 {
2997 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2998 	struct in_device *in_dev;
2999 
3000 	switch (event) {
3001 	case NETDEV_RESEND_IGMP:
3002 		in_dev = __in_dev_get_rtnl(dev);
3003 		if (in_dev)
3004 			ip_mc_rejoin_groups(in_dev);
3005 		break;
3006 	default:
3007 		break;
3008 	}
3009 	return NOTIFY_DONE;
3010 }
3011 
3012 static struct notifier_block igmp_notifier = {
3013 	.notifier_call = igmp_netdev_event,
3014 };
3015 
3016 int __init igmp_mc_init(void)
3017 {
3018 #if defined(CONFIG_PROC_FS)
3019 	int err;
3020 
3021 	err = register_pernet_subsys(&igmp_net_ops);
3022 	if (err)
3023 		return err;
3024 	err = register_netdevice_notifier(&igmp_notifier);
3025 	if (err)
3026 		goto reg_notif_fail;
3027 	return 0;
3028 
3029 reg_notif_fail:
3030 	unregister_pernet_subsys(&igmp_net_ops);
3031 	return err;
3032 #else
3033 	return register_netdevice_notifier(&igmp_notifier);
3034 #endif
3035 }
3036