xref: /openbmc/linux/net/ipv4/igmp.c (revision b6dcefde)
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 <asm/uaccess.h>
75 #include <asm/system.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 
92 #include <net/net_namespace.h>
93 #include <net/arp.h>
94 #include <net/ip.h>
95 #include <net/protocol.h>
96 #include <net/route.h>
97 #include <net/sock.h>
98 #include <net/checksum.h>
99 #include <linux/netfilter_ipv4.h>
100 #ifdef CONFIG_IP_MROUTE
101 #include <linux/mroute.h>
102 #endif
103 #ifdef CONFIG_PROC_FS
104 #include <linux/proc_fs.h>
105 #include <linux/seq_file.h>
106 #endif
107 
108 #define IP_MAX_MEMBERSHIPS	20
109 #define IP_MAX_MSF		10
110 
111 #ifdef CONFIG_IP_MULTICAST
112 /* Parameter names and values are taken from igmp-v2-06 draft */
113 
114 #define IGMP_V1_Router_Present_Timeout		(400*HZ)
115 #define IGMP_V2_Router_Present_Timeout		(400*HZ)
116 #define IGMP_Unsolicited_Report_Interval	(10*HZ)
117 #define IGMP_Query_Response_Interval		(10*HZ)
118 #define IGMP_Unsolicited_Report_Count		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 void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im);
142 static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr);
143 static void igmpv3_clear_delrec(struct in_device *in_dev);
144 static int sf_setstate(struct ip_mc_list *pmc);
145 static void sf_markstate(struct ip_mc_list *pmc);
146 #endif
147 static void ip_mc_clear_src(struct ip_mc_list *pmc);
148 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
149 			 int sfcount, __be32 *psfsrc, int delta);
150 
151 static void ip_ma_put(struct ip_mc_list *im)
152 {
153 	if (atomic_dec_and_test(&im->refcnt)) {
154 		in_dev_put(im->interface);
155 		kfree(im);
156 	}
157 }
158 
159 #ifdef CONFIG_IP_MULTICAST
160 
161 /*
162  *	Timer management
163  */
164 
165 static __inline__ void igmp_stop_timer(struct ip_mc_list *im)
166 {
167 	spin_lock_bh(&im->lock);
168 	if (del_timer(&im->timer))
169 		atomic_dec(&im->refcnt);
170 	im->tm_running = 0;
171 	im->reporter = 0;
172 	im->unsolicit_count = 0;
173 	spin_unlock_bh(&im->lock);
174 }
175 
176 /* It must be called with locked im->lock */
177 static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
178 {
179 	int tv = net_random() % max_delay;
180 
181 	im->tm_running = 1;
182 	if (!mod_timer(&im->timer, jiffies+tv+2))
183 		atomic_inc(&im->refcnt);
184 }
185 
186 static void igmp_gq_start_timer(struct in_device *in_dev)
187 {
188 	int tv = net_random() % in_dev->mr_maxdelay;
189 
190 	in_dev->mr_gq_running = 1;
191 	if (!mod_timer(&in_dev->mr_gq_timer, jiffies+tv+2))
192 		in_dev_hold(in_dev);
193 }
194 
195 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
196 {
197 	int tv = net_random() % delay;
198 
199 	if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
200 		in_dev_hold(in_dev);
201 }
202 
203 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
204 {
205 	spin_lock_bh(&im->lock);
206 	im->unsolicit_count = 0;
207 	if (del_timer(&im->timer)) {
208 		if ((long)(im->timer.expires-jiffies) < max_delay) {
209 			add_timer(&im->timer);
210 			im->tm_running = 1;
211 			spin_unlock_bh(&im->lock);
212 			return;
213 		}
214 		atomic_dec(&im->refcnt);
215 	}
216 	igmp_start_timer(im, max_delay);
217 	spin_unlock_bh(&im->lock);
218 }
219 
220 
221 /*
222  *	Send an IGMP report.
223  */
224 
225 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
226 
227 
228 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
229 	int gdeleted, int sdeleted)
230 {
231 	switch (type) {
232 	case IGMPV3_MODE_IS_INCLUDE:
233 	case IGMPV3_MODE_IS_EXCLUDE:
234 		if (gdeleted || sdeleted)
235 			return 0;
236 		if (!(pmc->gsquery && !psf->sf_gsresp)) {
237 			if (pmc->sfmode == MCAST_INCLUDE)
238 				return 1;
239 			/* don't include if this source is excluded
240 			 * in all filters
241 			 */
242 			if (psf->sf_count[MCAST_INCLUDE])
243 				return type == IGMPV3_MODE_IS_INCLUDE;
244 			return pmc->sfcount[MCAST_EXCLUDE] ==
245 				psf->sf_count[MCAST_EXCLUDE];
246 		}
247 		return 0;
248 	case IGMPV3_CHANGE_TO_INCLUDE:
249 		if (gdeleted || sdeleted)
250 			return 0;
251 		return psf->sf_count[MCAST_INCLUDE] != 0;
252 	case IGMPV3_CHANGE_TO_EXCLUDE:
253 		if (gdeleted || sdeleted)
254 			return 0;
255 		if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
256 		    psf->sf_count[MCAST_INCLUDE])
257 			return 0;
258 		return pmc->sfcount[MCAST_EXCLUDE] ==
259 			psf->sf_count[MCAST_EXCLUDE];
260 	case IGMPV3_ALLOW_NEW_SOURCES:
261 		if (gdeleted || !psf->sf_crcount)
262 			return 0;
263 		return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
264 	case IGMPV3_BLOCK_OLD_SOURCES:
265 		if (pmc->sfmode == MCAST_INCLUDE)
266 			return gdeleted || (psf->sf_crcount && sdeleted);
267 		return psf->sf_crcount && !gdeleted && !sdeleted;
268 	}
269 	return 0;
270 }
271 
272 static int
273 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
274 {
275 	struct ip_sf_list *psf;
276 	int scount = 0;
277 
278 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
279 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
280 			continue;
281 		scount++;
282 	}
283 	return scount;
284 }
285 
286 static struct sk_buff *igmpv3_newpack(struct net_device *dev, int size)
287 {
288 	struct sk_buff *skb;
289 	struct rtable *rt;
290 	struct iphdr *pip;
291 	struct igmpv3_report *pig;
292 	struct net *net = dev_net(dev);
293 
294 	skb = alloc_skb(size + LL_ALLOCATED_SPACE(dev), GFP_ATOMIC);
295 	if (skb == NULL)
296 		return NULL;
297 
298 	{
299 		struct flowi fl = { .oif = dev->ifindex,
300 				    .nl_u = { .ip4_u = {
301 				    .daddr = IGMPV3_ALL_MCR } },
302 				    .proto = IPPROTO_IGMP };
303 		if (ip_route_output_key(net, &rt, &fl)) {
304 			kfree_skb(skb);
305 			return NULL;
306 		}
307 	}
308 	if (rt->rt_src == 0) {
309 		kfree_skb(skb);
310 		ip_rt_put(rt);
311 		return NULL;
312 	}
313 
314 	skb_dst_set(skb, &rt->u.dst);
315 	skb->dev = dev;
316 
317 	skb_reserve(skb, LL_RESERVED_SPACE(dev));
318 
319 	skb_reset_network_header(skb);
320 	pip = ip_hdr(skb);
321 	skb_put(skb, sizeof(struct iphdr) + 4);
322 
323 	pip->version  = 4;
324 	pip->ihl      = (sizeof(struct iphdr)+4)>>2;
325 	pip->tos      = 0xc0;
326 	pip->frag_off = htons(IP_DF);
327 	pip->ttl      = 1;
328 	pip->daddr    = rt->rt_dst;
329 	pip->saddr    = rt->rt_src;
330 	pip->protocol = IPPROTO_IGMP;
331 	pip->tot_len  = 0;	/* filled in later */
332 	ip_select_ident(pip, &rt->u.dst, NULL);
333 	((u8*)&pip[1])[0] = IPOPT_RA;
334 	((u8*)&pip[1])[1] = 4;
335 	((u8*)&pip[1])[2] = 0;
336 	((u8*)&pip[1])[3] = 0;
337 
338 	skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
339 	skb_put(skb, sizeof(*pig));
340 	pig = igmpv3_report_hdr(skb);
341 	pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
342 	pig->resv1 = 0;
343 	pig->csum = 0;
344 	pig->resv2 = 0;
345 	pig->ngrec = 0;
346 	return skb;
347 }
348 
349 static int igmpv3_sendpack(struct sk_buff *skb)
350 {
351 	struct igmphdr *pig = igmp_hdr(skb);
352 	const int igmplen = skb->tail - skb->transport_header;
353 
354 	pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
355 
356 	return ip_local_out(skb);
357 }
358 
359 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
360 {
361 	return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
362 }
363 
364 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
365 	int type, struct igmpv3_grec **ppgr)
366 {
367 	struct net_device *dev = pmc->interface->dev;
368 	struct igmpv3_report *pih;
369 	struct igmpv3_grec *pgr;
370 
371 	if (!skb)
372 		skb = igmpv3_newpack(dev, dev->mtu);
373 	if (!skb)
374 		return NULL;
375 	pgr = (struct igmpv3_grec *)skb_put(skb, sizeof(struct igmpv3_grec));
376 	pgr->grec_type = type;
377 	pgr->grec_auxwords = 0;
378 	pgr->grec_nsrcs = 0;
379 	pgr->grec_mca = pmc->multiaddr;
380 	pih = igmpv3_report_hdr(skb);
381 	pih->ngrec = htons(ntohs(pih->ngrec)+1);
382 	*ppgr = pgr;
383 	return skb;
384 }
385 
386 #define AVAILABLE(skb) ((skb) ? ((skb)->dev ? (skb)->dev->mtu - (skb)->len : \
387 	skb_tailroom(skb)) : 0)
388 
389 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
390 	int type, int gdeleted, int sdeleted)
391 {
392 	struct net_device *dev = pmc->interface->dev;
393 	struct igmpv3_report *pih;
394 	struct igmpv3_grec *pgr = NULL;
395 	struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
396 	int scount, stotal, first, isquery, truncate;
397 
398 	if (pmc->multiaddr == IGMP_ALL_HOSTS)
399 		return skb;
400 
401 	isquery = type == IGMPV3_MODE_IS_INCLUDE ||
402 		  type == IGMPV3_MODE_IS_EXCLUDE;
403 	truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
404 		    type == IGMPV3_CHANGE_TO_EXCLUDE;
405 
406 	stotal = scount = 0;
407 
408 	psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
409 
410 	if (!*psf_list)
411 		goto empty_source;
412 
413 	pih = skb ? igmpv3_report_hdr(skb) : NULL;
414 
415 	/* EX and TO_EX get a fresh packet, if needed */
416 	if (truncate) {
417 		if (pih && pih->ngrec &&
418 		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
419 			if (skb)
420 				igmpv3_sendpack(skb);
421 			skb = igmpv3_newpack(dev, dev->mtu);
422 		}
423 	}
424 	first = 1;
425 	psf_prev = NULL;
426 	for (psf=*psf_list; psf; psf=psf_next) {
427 		__be32 *psrc;
428 
429 		psf_next = psf->sf_next;
430 
431 		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
432 			psf_prev = psf;
433 			continue;
434 		}
435 
436 		/* clear marks on query responses */
437 		if (isquery)
438 			psf->sf_gsresp = 0;
439 
440 		if (AVAILABLE(skb) < sizeof(__be32) +
441 		    first*sizeof(struct igmpv3_grec)) {
442 			if (truncate && !first)
443 				break;	 /* truncate these */
444 			if (pgr)
445 				pgr->grec_nsrcs = htons(scount);
446 			if (skb)
447 				igmpv3_sendpack(skb);
448 			skb = igmpv3_newpack(dev, dev->mtu);
449 			first = 1;
450 			scount = 0;
451 		}
452 		if (first) {
453 			skb = add_grhead(skb, pmc, type, &pgr);
454 			first = 0;
455 		}
456 		if (!skb)
457 			return NULL;
458 		psrc = (__be32 *)skb_put(skb, sizeof(__be32));
459 		*psrc = psf->sf_inaddr;
460 		scount++; stotal++;
461 		if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
462 		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
463 			psf->sf_crcount--;
464 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
465 				if (psf_prev)
466 					psf_prev->sf_next = psf->sf_next;
467 				else
468 					*psf_list = psf->sf_next;
469 				kfree(psf);
470 				continue;
471 			}
472 		}
473 		psf_prev = psf;
474 	}
475 
476 empty_source:
477 	if (!stotal) {
478 		if (type == IGMPV3_ALLOW_NEW_SOURCES ||
479 		    type == IGMPV3_BLOCK_OLD_SOURCES)
480 			return skb;
481 		if (pmc->crcount || isquery) {
482 			/* make sure we have room for group header */
483 			if (skb && AVAILABLE(skb)<sizeof(struct igmpv3_grec)) {
484 				igmpv3_sendpack(skb);
485 				skb = NULL; /* add_grhead will get a new one */
486 			}
487 			skb = add_grhead(skb, pmc, type, &pgr);
488 		}
489 	}
490 	if (pgr)
491 		pgr->grec_nsrcs = htons(scount);
492 
493 	if (isquery)
494 		pmc->gsquery = 0;	/* clear query state on report */
495 	return skb;
496 }
497 
498 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
499 {
500 	struct sk_buff *skb = NULL;
501 	int type;
502 
503 	if (!pmc) {
504 		read_lock(&in_dev->mc_list_lock);
505 		for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
506 			if (pmc->multiaddr == IGMP_ALL_HOSTS)
507 				continue;
508 			spin_lock_bh(&pmc->lock);
509 			if (pmc->sfcount[MCAST_EXCLUDE])
510 				type = IGMPV3_MODE_IS_EXCLUDE;
511 			else
512 				type = IGMPV3_MODE_IS_INCLUDE;
513 			skb = add_grec(skb, pmc, type, 0, 0);
514 			spin_unlock_bh(&pmc->lock);
515 		}
516 		read_unlock(&in_dev->mc_list_lock);
517 	} else {
518 		spin_lock_bh(&pmc->lock);
519 		if (pmc->sfcount[MCAST_EXCLUDE])
520 			type = IGMPV3_MODE_IS_EXCLUDE;
521 		else
522 			type = IGMPV3_MODE_IS_INCLUDE;
523 		skb = add_grec(skb, pmc, type, 0, 0);
524 		spin_unlock_bh(&pmc->lock);
525 	}
526 	if (!skb)
527 		return 0;
528 	return igmpv3_sendpack(skb);
529 }
530 
531 /*
532  * remove zero-count source records from a source filter list
533  */
534 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
535 {
536 	struct ip_sf_list *psf_prev, *psf_next, *psf;
537 
538 	psf_prev = NULL;
539 	for (psf=*ppsf; psf; psf = psf_next) {
540 		psf_next = psf->sf_next;
541 		if (psf->sf_crcount == 0) {
542 			if (psf_prev)
543 				psf_prev->sf_next = psf->sf_next;
544 			else
545 				*ppsf = psf->sf_next;
546 			kfree(psf);
547 		} else
548 			psf_prev = psf;
549 	}
550 }
551 
552 static void igmpv3_send_cr(struct in_device *in_dev)
553 {
554 	struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
555 	struct sk_buff *skb = NULL;
556 	int type, dtype;
557 
558 	read_lock(&in_dev->mc_list_lock);
559 	spin_lock_bh(&in_dev->mc_tomb_lock);
560 
561 	/* deleted MCA's */
562 	pmc_prev = NULL;
563 	for (pmc=in_dev->mc_tomb; pmc; pmc=pmc_next) {
564 		pmc_next = pmc->next;
565 		if (pmc->sfmode == MCAST_INCLUDE) {
566 			type = IGMPV3_BLOCK_OLD_SOURCES;
567 			dtype = IGMPV3_BLOCK_OLD_SOURCES;
568 			skb = add_grec(skb, pmc, type, 1, 0);
569 			skb = add_grec(skb, pmc, dtype, 1, 1);
570 		}
571 		if (pmc->crcount) {
572 			if (pmc->sfmode == MCAST_EXCLUDE) {
573 				type = IGMPV3_CHANGE_TO_INCLUDE;
574 				skb = add_grec(skb, pmc, type, 1, 0);
575 			}
576 			pmc->crcount--;
577 			if (pmc->crcount == 0) {
578 				igmpv3_clear_zeros(&pmc->tomb);
579 				igmpv3_clear_zeros(&pmc->sources);
580 			}
581 		}
582 		if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
583 			if (pmc_prev)
584 				pmc_prev->next = pmc_next;
585 			else
586 				in_dev->mc_tomb = pmc_next;
587 			in_dev_put(pmc->interface);
588 			kfree(pmc);
589 		} else
590 			pmc_prev = pmc;
591 	}
592 	spin_unlock_bh(&in_dev->mc_tomb_lock);
593 
594 	/* change recs */
595 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
596 		spin_lock_bh(&pmc->lock);
597 		if (pmc->sfcount[MCAST_EXCLUDE]) {
598 			type = IGMPV3_BLOCK_OLD_SOURCES;
599 			dtype = IGMPV3_ALLOW_NEW_SOURCES;
600 		} else {
601 			type = IGMPV3_ALLOW_NEW_SOURCES;
602 			dtype = IGMPV3_BLOCK_OLD_SOURCES;
603 		}
604 		skb = add_grec(skb, pmc, type, 0, 0);
605 		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
606 
607 		/* filter mode changes */
608 		if (pmc->crcount) {
609 			if (pmc->sfmode == MCAST_EXCLUDE)
610 				type = IGMPV3_CHANGE_TO_EXCLUDE;
611 			else
612 				type = IGMPV3_CHANGE_TO_INCLUDE;
613 			skb = add_grec(skb, pmc, type, 0, 0);
614 			pmc->crcount--;
615 		}
616 		spin_unlock_bh(&pmc->lock);
617 	}
618 	read_unlock(&in_dev->mc_list_lock);
619 
620 	if (!skb)
621 		return;
622 	(void) igmpv3_sendpack(skb);
623 }
624 
625 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
626 	int type)
627 {
628 	struct sk_buff *skb;
629 	struct iphdr *iph;
630 	struct igmphdr *ih;
631 	struct rtable *rt;
632 	struct net_device *dev = in_dev->dev;
633 	struct net *net = dev_net(dev);
634 	__be32	group = pmc ? pmc->multiaddr : 0;
635 	__be32	dst;
636 
637 	if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
638 		return igmpv3_send_report(in_dev, pmc);
639 	else if (type == IGMP_HOST_LEAVE_MESSAGE)
640 		dst = IGMP_ALL_ROUTER;
641 	else
642 		dst = group;
643 
644 	{
645 		struct flowi fl = { .oif = dev->ifindex,
646 				    .nl_u = { .ip4_u = { .daddr = dst } },
647 				    .proto = IPPROTO_IGMP };
648 		if (ip_route_output_key(net, &rt, &fl))
649 			return -1;
650 	}
651 	if (rt->rt_src == 0) {
652 		ip_rt_put(rt);
653 		return -1;
654 	}
655 
656 	skb = alloc_skb(IGMP_SIZE+LL_ALLOCATED_SPACE(dev), GFP_ATOMIC);
657 	if (skb == NULL) {
658 		ip_rt_put(rt);
659 		return -1;
660 	}
661 
662 	skb_dst_set(skb, &rt->u.dst);
663 
664 	skb_reserve(skb, LL_RESERVED_SPACE(dev));
665 
666 	skb_reset_network_header(skb);
667 	iph = ip_hdr(skb);
668 	skb_put(skb, sizeof(struct iphdr) + 4);
669 
670 	iph->version  = 4;
671 	iph->ihl      = (sizeof(struct iphdr)+4)>>2;
672 	iph->tos      = 0xc0;
673 	iph->frag_off = htons(IP_DF);
674 	iph->ttl      = 1;
675 	iph->daddr    = dst;
676 	iph->saddr    = rt->rt_src;
677 	iph->protocol = IPPROTO_IGMP;
678 	ip_select_ident(iph, &rt->u.dst, NULL);
679 	((u8*)&iph[1])[0] = IPOPT_RA;
680 	((u8*)&iph[1])[1] = 4;
681 	((u8*)&iph[1])[2] = 0;
682 	((u8*)&iph[1])[3] = 0;
683 
684 	ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
685 	ih->type = type;
686 	ih->code = 0;
687 	ih->csum = 0;
688 	ih->group = group;
689 	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
690 
691 	return ip_local_out(skb);
692 }
693 
694 static void igmp_gq_timer_expire(unsigned long data)
695 {
696 	struct in_device *in_dev = (struct in_device *)data;
697 
698 	in_dev->mr_gq_running = 0;
699 	igmpv3_send_report(in_dev, NULL);
700 	__in_dev_put(in_dev);
701 }
702 
703 static void igmp_ifc_timer_expire(unsigned long data)
704 {
705 	struct in_device *in_dev = (struct in_device *)data;
706 
707 	igmpv3_send_cr(in_dev);
708 	if (in_dev->mr_ifc_count) {
709 		in_dev->mr_ifc_count--;
710 		igmp_ifc_start_timer(in_dev, IGMP_Unsolicited_Report_Interval);
711 	}
712 	__in_dev_put(in_dev);
713 }
714 
715 static void igmp_ifc_event(struct in_device *in_dev)
716 {
717 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
718 		return;
719 	in_dev->mr_ifc_count = in_dev->mr_qrv ? in_dev->mr_qrv :
720 		IGMP_Unsolicited_Report_Count;
721 	igmp_ifc_start_timer(in_dev, 1);
722 }
723 
724 
725 static void igmp_timer_expire(unsigned long data)
726 {
727 	struct ip_mc_list *im=(struct ip_mc_list *)data;
728 	struct in_device *in_dev = im->interface;
729 
730 	spin_lock(&im->lock);
731 	im->tm_running = 0;
732 
733 	if (im->unsolicit_count) {
734 		im->unsolicit_count--;
735 		igmp_start_timer(im, IGMP_Unsolicited_Report_Interval);
736 	}
737 	im->reporter = 1;
738 	spin_unlock(&im->lock);
739 
740 	if (IGMP_V1_SEEN(in_dev))
741 		igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
742 	else if (IGMP_V2_SEEN(in_dev))
743 		igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
744 	else
745 		igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
746 
747 	ip_ma_put(im);
748 }
749 
750 /* mark EXCLUDE-mode sources */
751 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
752 {
753 	struct ip_sf_list *psf;
754 	int i, scount;
755 
756 	scount = 0;
757 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
758 		if (scount == nsrcs)
759 			break;
760 		for (i=0; i<nsrcs; i++) {
761 			/* skip inactive filters */
762 			if (pmc->sfcount[MCAST_INCLUDE] ||
763 			    pmc->sfcount[MCAST_EXCLUDE] !=
764 			    psf->sf_count[MCAST_EXCLUDE])
765 				continue;
766 			if (srcs[i] == psf->sf_inaddr) {
767 				scount++;
768 				break;
769 			}
770 		}
771 	}
772 	pmc->gsquery = 0;
773 	if (scount == nsrcs)	/* all sources excluded */
774 		return 0;
775 	return 1;
776 }
777 
778 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
779 {
780 	struct ip_sf_list *psf;
781 	int i, scount;
782 
783 	if (pmc->sfmode == MCAST_EXCLUDE)
784 		return igmp_xmarksources(pmc, nsrcs, srcs);
785 
786 	/* mark INCLUDE-mode sources */
787 	scount = 0;
788 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
789 		if (scount == nsrcs)
790 			break;
791 		for (i=0; i<nsrcs; i++)
792 			if (srcs[i] == psf->sf_inaddr) {
793 				psf->sf_gsresp = 1;
794 				scount++;
795 				break;
796 			}
797 	}
798 	if (!scount) {
799 		pmc->gsquery = 0;
800 		return 0;
801 	}
802 	pmc->gsquery = 1;
803 	return 1;
804 }
805 
806 static void igmp_heard_report(struct in_device *in_dev, __be32 group)
807 {
808 	struct ip_mc_list *im;
809 
810 	/* Timers are only set for non-local groups */
811 
812 	if (group == IGMP_ALL_HOSTS)
813 		return;
814 
815 	read_lock(&in_dev->mc_list_lock);
816 	for (im=in_dev->mc_list; im!=NULL; im=im->next) {
817 		if (im->multiaddr == group) {
818 			igmp_stop_timer(im);
819 			break;
820 		}
821 	}
822 	read_unlock(&in_dev->mc_list_lock);
823 }
824 
825 static void igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
826 	int len)
827 {
828 	struct igmphdr 		*ih = igmp_hdr(skb);
829 	struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
830 	struct ip_mc_list	*im;
831 	__be32			group = ih->group;
832 	int			max_delay;
833 	int			mark = 0;
834 
835 
836 	if (len == 8) {
837 		if (ih->code == 0) {
838 			/* Alas, old v1 router presents here. */
839 
840 			max_delay = IGMP_Query_Response_Interval;
841 			in_dev->mr_v1_seen = jiffies +
842 				IGMP_V1_Router_Present_Timeout;
843 			group = 0;
844 		} else {
845 			/* v2 router present */
846 			max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
847 			in_dev->mr_v2_seen = jiffies +
848 				IGMP_V2_Router_Present_Timeout;
849 		}
850 		/* cancel the interface change timer */
851 		in_dev->mr_ifc_count = 0;
852 		if (del_timer(&in_dev->mr_ifc_timer))
853 			__in_dev_put(in_dev);
854 		/* clear deleted report items */
855 		igmpv3_clear_delrec(in_dev);
856 	} else if (len < 12) {
857 		return;	/* ignore bogus packet; freed by caller */
858 	} else { /* v3 */
859 		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
860 			return;
861 
862 		ih3 = igmpv3_query_hdr(skb);
863 		if (ih3->nsrcs) {
864 			if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
865 					   + ntohs(ih3->nsrcs)*sizeof(__be32)))
866 				return;
867 			ih3 = igmpv3_query_hdr(skb);
868 		}
869 
870 		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
871 		if (!max_delay)
872 			max_delay = 1;	/* can't mod w/ 0 */
873 		in_dev->mr_maxdelay = max_delay;
874 		if (ih3->qrv)
875 			in_dev->mr_qrv = ih3->qrv;
876 		if (!group) { /* general query */
877 			if (ih3->nsrcs)
878 				return;	/* no sources allowed */
879 			igmp_gq_start_timer(in_dev);
880 			return;
881 		}
882 		/* mark sources to include, if group & source-specific */
883 		mark = ih3->nsrcs != 0;
884 	}
885 
886 	/*
887 	 * - Start the timers in all of our membership records
888 	 *   that the query applies to for the interface on
889 	 *   which the query arrived excl. those that belong
890 	 *   to a "local" group (224.0.0.X)
891 	 * - For timers already running check if they need to
892 	 *   be reset.
893 	 * - Use the igmp->igmp_code field as the maximum
894 	 *   delay possible
895 	 */
896 	read_lock(&in_dev->mc_list_lock);
897 	for (im=in_dev->mc_list; im!=NULL; im=im->next) {
898 		int changed;
899 
900 		if (group && group != im->multiaddr)
901 			continue;
902 		if (im->multiaddr == IGMP_ALL_HOSTS)
903 			continue;
904 		spin_lock_bh(&im->lock);
905 		if (im->tm_running)
906 			im->gsquery = im->gsquery && mark;
907 		else
908 			im->gsquery = mark;
909 		changed = !im->gsquery ||
910 			igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
911 		spin_unlock_bh(&im->lock);
912 		if (changed)
913 			igmp_mod_timer(im, max_delay);
914 	}
915 	read_unlock(&in_dev->mc_list_lock);
916 }
917 
918 int igmp_rcv(struct sk_buff *skb)
919 {
920 	/* This basically follows the spec line by line -- see RFC1112 */
921 	struct igmphdr *ih;
922 	struct in_device *in_dev = in_dev_get(skb->dev);
923 	int len = skb->len;
924 
925 	if (in_dev == NULL)
926 		goto drop;
927 
928 	if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
929 		goto drop_ref;
930 
931 	switch (skb->ip_summed) {
932 	case CHECKSUM_COMPLETE:
933 		if (!csum_fold(skb->csum))
934 			break;
935 		/* fall through */
936 	case CHECKSUM_NONE:
937 		skb->csum = 0;
938 		if (__skb_checksum_complete(skb))
939 			goto drop_ref;
940 	}
941 
942 	ih = igmp_hdr(skb);
943 	switch (ih->type) {
944 	case IGMP_HOST_MEMBERSHIP_QUERY:
945 		igmp_heard_query(in_dev, skb, len);
946 		break;
947 	case IGMP_HOST_MEMBERSHIP_REPORT:
948 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
949 		/* Is it our report looped back? */
950 		if (skb_rtable(skb)->fl.iif == 0)
951 			break;
952 		/* don't rely on MC router hearing unicast reports */
953 		if (skb->pkt_type == PACKET_MULTICAST ||
954 		    skb->pkt_type == PACKET_BROADCAST)
955 			igmp_heard_report(in_dev, ih->group);
956 		break;
957 	case IGMP_PIM:
958 #ifdef CONFIG_IP_PIMSM_V1
959 		in_dev_put(in_dev);
960 		return pim_rcv_v1(skb);
961 #endif
962 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
963 	case IGMP_DVMRP:
964 	case IGMP_TRACE:
965 	case IGMP_HOST_LEAVE_MESSAGE:
966 	case IGMP_MTRACE:
967 	case IGMP_MTRACE_RESP:
968 		break;
969 	default:
970 		break;
971 	}
972 
973 drop_ref:
974 	in_dev_put(in_dev);
975 drop:
976 	kfree_skb(skb);
977 	return 0;
978 }
979 
980 #endif
981 
982 
983 /*
984  *	Add a filter to a device
985  */
986 
987 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
988 {
989 	char buf[MAX_ADDR_LEN];
990 	struct net_device *dev = in_dev->dev;
991 
992 	/* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
993 	   We will get multicast token leakage, when IFF_MULTICAST
994 	   is changed. This check should be done in dev->set_multicast_list
995 	   routine. Something sort of:
996 	   if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
997 	   --ANK
998 	   */
999 	if (arp_mc_map(addr, buf, dev, 0) == 0)
1000 		dev_mc_add(dev, buf, dev->addr_len, 0);
1001 }
1002 
1003 /*
1004  *	Remove a filter from a device
1005  */
1006 
1007 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1008 {
1009 	char buf[MAX_ADDR_LEN];
1010 	struct net_device *dev = in_dev->dev;
1011 
1012 	if (arp_mc_map(addr, buf, dev, 0) == 0)
1013 		dev_mc_delete(dev, buf, dev->addr_len, 0);
1014 }
1015 
1016 #ifdef CONFIG_IP_MULTICAST
1017 /*
1018  * deleted ip_mc_list manipulation
1019  */
1020 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1021 {
1022 	struct ip_mc_list *pmc;
1023 
1024 	/* this is an "ip_mc_list" for convenience; only the fields below
1025 	 * are actually used. In particular, the refcnt and users are not
1026 	 * used for management of the delete list. Using the same structure
1027 	 * for deleted items allows change reports to use common code with
1028 	 * non-deleted or query-response MCA's.
1029 	 */
1030 	pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
1031 	if (!pmc)
1032 		return;
1033 	spin_lock_bh(&im->lock);
1034 	pmc->interface = im->interface;
1035 	in_dev_hold(in_dev);
1036 	pmc->multiaddr = im->multiaddr;
1037 	pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1038 		IGMP_Unsolicited_Report_Count;
1039 	pmc->sfmode = im->sfmode;
1040 	if (pmc->sfmode == MCAST_INCLUDE) {
1041 		struct ip_sf_list *psf;
1042 
1043 		pmc->tomb = im->tomb;
1044 		pmc->sources = im->sources;
1045 		im->tomb = im->sources = NULL;
1046 		for (psf=pmc->sources; psf; psf=psf->sf_next)
1047 			psf->sf_crcount = pmc->crcount;
1048 	}
1049 	spin_unlock_bh(&im->lock);
1050 
1051 	spin_lock_bh(&in_dev->mc_tomb_lock);
1052 	pmc->next = in_dev->mc_tomb;
1053 	in_dev->mc_tomb = pmc;
1054 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1055 }
1056 
1057 static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr)
1058 {
1059 	struct ip_mc_list *pmc, *pmc_prev;
1060 	struct ip_sf_list *psf, *psf_next;
1061 
1062 	spin_lock_bh(&in_dev->mc_tomb_lock);
1063 	pmc_prev = NULL;
1064 	for (pmc=in_dev->mc_tomb; pmc; pmc=pmc->next) {
1065 		if (pmc->multiaddr == multiaddr)
1066 			break;
1067 		pmc_prev = pmc;
1068 	}
1069 	if (pmc) {
1070 		if (pmc_prev)
1071 			pmc_prev->next = pmc->next;
1072 		else
1073 			in_dev->mc_tomb = pmc->next;
1074 	}
1075 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1076 	if (pmc) {
1077 		for (psf=pmc->tomb; psf; psf=psf_next) {
1078 			psf_next = psf->sf_next;
1079 			kfree(psf);
1080 		}
1081 		in_dev_put(pmc->interface);
1082 		kfree(pmc);
1083 	}
1084 }
1085 
1086 static void igmpv3_clear_delrec(struct in_device *in_dev)
1087 {
1088 	struct ip_mc_list *pmc, *nextpmc;
1089 
1090 	spin_lock_bh(&in_dev->mc_tomb_lock);
1091 	pmc = in_dev->mc_tomb;
1092 	in_dev->mc_tomb = NULL;
1093 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1094 
1095 	for (; pmc; pmc = nextpmc) {
1096 		nextpmc = pmc->next;
1097 		ip_mc_clear_src(pmc);
1098 		in_dev_put(pmc->interface);
1099 		kfree(pmc);
1100 	}
1101 	/* clear dead sources, too */
1102 	read_lock(&in_dev->mc_list_lock);
1103 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1104 		struct ip_sf_list *psf, *psf_next;
1105 
1106 		spin_lock_bh(&pmc->lock);
1107 		psf = pmc->tomb;
1108 		pmc->tomb = NULL;
1109 		spin_unlock_bh(&pmc->lock);
1110 		for (; psf; psf=psf_next) {
1111 			psf_next = psf->sf_next;
1112 			kfree(psf);
1113 		}
1114 	}
1115 	read_unlock(&in_dev->mc_list_lock);
1116 }
1117 #endif
1118 
1119 static void igmp_group_dropped(struct ip_mc_list *im)
1120 {
1121 	struct in_device *in_dev = im->interface;
1122 #ifdef CONFIG_IP_MULTICAST
1123 	int reporter;
1124 #endif
1125 
1126 	if (im->loaded) {
1127 		im->loaded = 0;
1128 		ip_mc_filter_del(in_dev, im->multiaddr);
1129 	}
1130 
1131 #ifdef CONFIG_IP_MULTICAST
1132 	if (im->multiaddr == IGMP_ALL_HOSTS)
1133 		return;
1134 
1135 	reporter = im->reporter;
1136 	igmp_stop_timer(im);
1137 
1138 	if (!in_dev->dead) {
1139 		if (IGMP_V1_SEEN(in_dev))
1140 			goto done;
1141 		if (IGMP_V2_SEEN(in_dev)) {
1142 			if (reporter)
1143 				igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1144 			goto done;
1145 		}
1146 		/* IGMPv3 */
1147 		igmpv3_add_delrec(in_dev, im);
1148 
1149 		igmp_ifc_event(in_dev);
1150 	}
1151 done:
1152 #endif
1153 	ip_mc_clear_src(im);
1154 }
1155 
1156 static void igmp_group_added(struct ip_mc_list *im)
1157 {
1158 	struct in_device *in_dev = im->interface;
1159 
1160 	if (im->loaded == 0) {
1161 		im->loaded = 1;
1162 		ip_mc_filter_add(in_dev, im->multiaddr);
1163 	}
1164 
1165 #ifdef CONFIG_IP_MULTICAST
1166 	if (im->multiaddr == IGMP_ALL_HOSTS)
1167 		return;
1168 
1169 	if (in_dev->dead)
1170 		return;
1171 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1172 		spin_lock_bh(&im->lock);
1173 		igmp_start_timer(im, IGMP_Initial_Report_Delay);
1174 		spin_unlock_bh(&im->lock);
1175 		return;
1176 	}
1177 	/* else, v3 */
1178 
1179 	im->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1180 		IGMP_Unsolicited_Report_Count;
1181 	igmp_ifc_event(in_dev);
1182 #endif
1183 }
1184 
1185 
1186 /*
1187  *	Multicast list managers
1188  */
1189 
1190 
1191 /*
1192  *	A socket has joined a multicast group on device dev.
1193  */
1194 
1195 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1196 {
1197 	struct ip_mc_list *im;
1198 
1199 	ASSERT_RTNL();
1200 
1201 	for (im=in_dev->mc_list; im; im=im->next) {
1202 		if (im->multiaddr == addr) {
1203 			im->users++;
1204 			ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1205 			goto out;
1206 		}
1207 	}
1208 
1209 	im = kmalloc(sizeof(*im), GFP_KERNEL);
1210 	if (!im)
1211 		goto out;
1212 
1213 	im->users = 1;
1214 	im->interface = in_dev;
1215 	in_dev_hold(in_dev);
1216 	im->multiaddr = addr;
1217 	/* initial mode is (EX, empty) */
1218 	im->sfmode = MCAST_EXCLUDE;
1219 	im->sfcount[MCAST_INCLUDE] = 0;
1220 	im->sfcount[MCAST_EXCLUDE] = 1;
1221 	im->sources = NULL;
1222 	im->tomb = NULL;
1223 	im->crcount = 0;
1224 	atomic_set(&im->refcnt, 1);
1225 	spin_lock_init(&im->lock);
1226 #ifdef CONFIG_IP_MULTICAST
1227 	im->tm_running = 0;
1228 	setup_timer(&im->timer, &igmp_timer_expire, (unsigned long)im);
1229 	im->unsolicit_count = IGMP_Unsolicited_Report_Count;
1230 	im->reporter = 0;
1231 	im->gsquery = 0;
1232 #endif
1233 	im->loaded = 0;
1234 	write_lock_bh(&in_dev->mc_list_lock);
1235 	im->next = in_dev->mc_list;
1236 	in_dev->mc_list = im;
1237 	in_dev->mc_count++;
1238 	write_unlock_bh(&in_dev->mc_list_lock);
1239 #ifdef CONFIG_IP_MULTICAST
1240 	igmpv3_del_delrec(in_dev, im->multiaddr);
1241 #endif
1242 	igmp_group_added(im);
1243 	if (!in_dev->dead)
1244 		ip_rt_multicast_event(in_dev);
1245 out:
1246 	return;
1247 }
1248 
1249 /*
1250  *	Resend IGMP JOIN report; used for bonding.
1251  */
1252 void ip_mc_rejoin_group(struct ip_mc_list *im)
1253 {
1254 #ifdef CONFIG_IP_MULTICAST
1255 	struct in_device *in_dev = im->interface;
1256 
1257 	if (im->multiaddr == IGMP_ALL_HOSTS)
1258 		return;
1259 
1260 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1261 		igmp_mod_timer(im, IGMP_Initial_Report_Delay);
1262 		return;
1263 	}
1264 	/* else, v3 */
1265 	im->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1266 		IGMP_Unsolicited_Report_Count;
1267 	igmp_ifc_event(in_dev);
1268 #endif
1269 }
1270 
1271 /*
1272  *	A socket has left a multicast group on device dev
1273  */
1274 
1275 void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
1276 {
1277 	struct ip_mc_list *i, **ip;
1278 
1279 	ASSERT_RTNL();
1280 
1281 	for (ip=&in_dev->mc_list; (i=*ip)!=NULL; ip=&i->next) {
1282 		if (i->multiaddr == addr) {
1283 			if (--i->users == 0) {
1284 				write_lock_bh(&in_dev->mc_list_lock);
1285 				*ip = i->next;
1286 				in_dev->mc_count--;
1287 				write_unlock_bh(&in_dev->mc_list_lock);
1288 				igmp_group_dropped(i);
1289 
1290 				if (!in_dev->dead)
1291 					ip_rt_multicast_event(in_dev);
1292 
1293 				ip_ma_put(i);
1294 				return;
1295 			}
1296 			break;
1297 		}
1298 	}
1299 }
1300 
1301 /* Device changing type */
1302 
1303 void ip_mc_unmap(struct in_device *in_dev)
1304 {
1305 	struct ip_mc_list *i;
1306 
1307 	ASSERT_RTNL();
1308 
1309 	for (i = in_dev->mc_list; i; i = i->next)
1310 		igmp_group_dropped(i);
1311 }
1312 
1313 void ip_mc_remap(struct in_device *in_dev)
1314 {
1315 	struct ip_mc_list *i;
1316 
1317 	ASSERT_RTNL();
1318 
1319 	for (i = in_dev->mc_list; i; i = i->next)
1320 		igmp_group_added(i);
1321 }
1322 
1323 /* Device going down */
1324 
1325 void ip_mc_down(struct in_device *in_dev)
1326 {
1327 	struct ip_mc_list *i;
1328 
1329 	ASSERT_RTNL();
1330 
1331 	for (i=in_dev->mc_list; i; i=i->next)
1332 		igmp_group_dropped(i);
1333 
1334 #ifdef CONFIG_IP_MULTICAST
1335 	in_dev->mr_ifc_count = 0;
1336 	if (del_timer(&in_dev->mr_ifc_timer))
1337 		__in_dev_put(in_dev);
1338 	in_dev->mr_gq_running = 0;
1339 	if (del_timer(&in_dev->mr_gq_timer))
1340 		__in_dev_put(in_dev);
1341 	igmpv3_clear_delrec(in_dev);
1342 #endif
1343 
1344 	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1345 }
1346 
1347 void ip_mc_init_dev(struct in_device *in_dev)
1348 {
1349 	ASSERT_RTNL();
1350 
1351 	in_dev->mc_tomb = NULL;
1352 #ifdef CONFIG_IP_MULTICAST
1353 	in_dev->mr_gq_running = 0;
1354 	setup_timer(&in_dev->mr_gq_timer, igmp_gq_timer_expire,
1355 			(unsigned long)in_dev);
1356 	in_dev->mr_ifc_count = 0;
1357 	in_dev->mc_count     = 0;
1358 	setup_timer(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire,
1359 			(unsigned long)in_dev);
1360 	in_dev->mr_qrv = IGMP_Unsolicited_Report_Count;
1361 #endif
1362 
1363 	rwlock_init(&in_dev->mc_list_lock);
1364 	spin_lock_init(&in_dev->mc_tomb_lock);
1365 }
1366 
1367 /* Device going up */
1368 
1369 void ip_mc_up(struct in_device *in_dev)
1370 {
1371 	struct ip_mc_list *i;
1372 
1373 	ASSERT_RTNL();
1374 
1375 	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1376 
1377 	for (i=in_dev->mc_list; i; i=i->next)
1378 		igmp_group_added(i);
1379 }
1380 
1381 /*
1382  *	Device is about to be destroyed: clean up.
1383  */
1384 
1385 void ip_mc_destroy_dev(struct in_device *in_dev)
1386 {
1387 	struct ip_mc_list *i;
1388 
1389 	ASSERT_RTNL();
1390 
1391 	/* Deactivate timers */
1392 	ip_mc_down(in_dev);
1393 
1394 	write_lock_bh(&in_dev->mc_list_lock);
1395 	while ((i = in_dev->mc_list) != NULL) {
1396 		in_dev->mc_list = i->next;
1397 		in_dev->mc_count--;
1398 		write_unlock_bh(&in_dev->mc_list_lock);
1399 		igmp_group_dropped(i);
1400 		ip_ma_put(i);
1401 
1402 		write_lock_bh(&in_dev->mc_list_lock);
1403 	}
1404 	write_unlock_bh(&in_dev->mc_list_lock);
1405 }
1406 
1407 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1408 {
1409 	struct flowi fl = { .nl_u = { .ip4_u =
1410 				      { .daddr = imr->imr_multiaddr.s_addr } } };
1411 	struct rtable *rt;
1412 	struct net_device *dev = NULL;
1413 	struct in_device *idev = NULL;
1414 
1415 	if (imr->imr_ifindex) {
1416 		idev = inetdev_by_index(net, imr->imr_ifindex);
1417 		if (idev)
1418 			__in_dev_put(idev);
1419 		return idev;
1420 	}
1421 	if (imr->imr_address.s_addr) {
1422 		dev = ip_dev_find(net, imr->imr_address.s_addr);
1423 		if (!dev)
1424 			return NULL;
1425 		dev_put(dev);
1426 	}
1427 
1428 	if (!dev && !ip_route_output_key(net, &rt, &fl)) {
1429 		dev = rt->u.dst.dev;
1430 		ip_rt_put(rt);
1431 	}
1432 	if (dev) {
1433 		imr->imr_ifindex = dev->ifindex;
1434 		idev = __in_dev_get_rtnl(dev);
1435 	}
1436 	return idev;
1437 }
1438 
1439 /*
1440  *	Join a socket to a group
1441  */
1442 int sysctl_igmp_max_memberships __read_mostly = IP_MAX_MEMBERSHIPS;
1443 int sysctl_igmp_max_msf __read_mostly = IP_MAX_MSF;
1444 
1445 
1446 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1447 	__be32 *psfsrc)
1448 {
1449 	struct ip_sf_list *psf, *psf_prev;
1450 	int rv = 0;
1451 
1452 	psf_prev = NULL;
1453 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1454 		if (psf->sf_inaddr == *psfsrc)
1455 			break;
1456 		psf_prev = psf;
1457 	}
1458 	if (!psf || psf->sf_count[sfmode] == 0) {
1459 		/* source filter not found, or count wrong =>  bug */
1460 		return -ESRCH;
1461 	}
1462 	psf->sf_count[sfmode]--;
1463 	if (psf->sf_count[sfmode] == 0) {
1464 		ip_rt_multicast_event(pmc->interface);
1465 	}
1466 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1467 #ifdef CONFIG_IP_MULTICAST
1468 		struct in_device *in_dev = pmc->interface;
1469 #endif
1470 
1471 		/* no more filters for this source */
1472 		if (psf_prev)
1473 			psf_prev->sf_next = psf->sf_next;
1474 		else
1475 			pmc->sources = psf->sf_next;
1476 #ifdef CONFIG_IP_MULTICAST
1477 		if (psf->sf_oldin &&
1478 		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1479 			psf->sf_crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1480 				IGMP_Unsolicited_Report_Count;
1481 			psf->sf_next = pmc->tomb;
1482 			pmc->tomb = psf;
1483 			rv = 1;
1484 		} else
1485 #endif
1486 			kfree(psf);
1487 	}
1488 	return rv;
1489 }
1490 
1491 #ifndef CONFIG_IP_MULTICAST
1492 #define igmp_ifc_event(x)	do { } while (0)
1493 #endif
1494 
1495 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1496 			 int sfcount, __be32 *psfsrc, int delta)
1497 {
1498 	struct ip_mc_list *pmc;
1499 	int	changerec = 0;
1500 	int	i, err;
1501 
1502 	if (!in_dev)
1503 		return -ENODEV;
1504 	read_lock(&in_dev->mc_list_lock);
1505 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1506 		if (*pmca == pmc->multiaddr)
1507 			break;
1508 	}
1509 	if (!pmc) {
1510 		/* MCA not found?? bug */
1511 		read_unlock(&in_dev->mc_list_lock);
1512 		return -ESRCH;
1513 	}
1514 	spin_lock_bh(&pmc->lock);
1515 	read_unlock(&in_dev->mc_list_lock);
1516 #ifdef CONFIG_IP_MULTICAST
1517 	sf_markstate(pmc);
1518 #endif
1519 	if (!delta) {
1520 		err = -EINVAL;
1521 		if (!pmc->sfcount[sfmode])
1522 			goto out_unlock;
1523 		pmc->sfcount[sfmode]--;
1524 	}
1525 	err = 0;
1526 	for (i=0; i<sfcount; i++) {
1527 		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1528 
1529 		changerec |= rv > 0;
1530 		if (!err && rv < 0)
1531 			err = rv;
1532 	}
1533 	if (pmc->sfmode == MCAST_EXCLUDE &&
1534 	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1535 	    pmc->sfcount[MCAST_INCLUDE]) {
1536 #ifdef CONFIG_IP_MULTICAST
1537 		struct ip_sf_list *psf;
1538 #endif
1539 
1540 		/* filter mode change */
1541 		pmc->sfmode = MCAST_INCLUDE;
1542 #ifdef CONFIG_IP_MULTICAST
1543 		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1544 			IGMP_Unsolicited_Report_Count;
1545 		in_dev->mr_ifc_count = pmc->crcount;
1546 		for (psf=pmc->sources; psf; psf = psf->sf_next)
1547 			psf->sf_crcount = 0;
1548 		igmp_ifc_event(pmc->interface);
1549 	} else if (sf_setstate(pmc) || changerec) {
1550 		igmp_ifc_event(pmc->interface);
1551 #endif
1552 	}
1553 out_unlock:
1554 	spin_unlock_bh(&pmc->lock);
1555 	return err;
1556 }
1557 
1558 /*
1559  * Add multicast single-source filter to the interface list
1560  */
1561 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1562 	__be32 *psfsrc, int delta)
1563 {
1564 	struct ip_sf_list *psf, *psf_prev;
1565 
1566 	psf_prev = NULL;
1567 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1568 		if (psf->sf_inaddr == *psfsrc)
1569 			break;
1570 		psf_prev = psf;
1571 	}
1572 	if (!psf) {
1573 		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1574 		if (!psf)
1575 			return -ENOBUFS;
1576 		psf->sf_inaddr = *psfsrc;
1577 		if (psf_prev) {
1578 			psf_prev->sf_next = psf;
1579 		} else
1580 			pmc->sources = psf;
1581 	}
1582 	psf->sf_count[sfmode]++;
1583 	if (psf->sf_count[sfmode] == 1) {
1584 		ip_rt_multicast_event(pmc->interface);
1585 	}
1586 	return 0;
1587 }
1588 
1589 #ifdef CONFIG_IP_MULTICAST
1590 static void sf_markstate(struct ip_mc_list *pmc)
1591 {
1592 	struct ip_sf_list *psf;
1593 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1594 
1595 	for (psf=pmc->sources; psf; psf=psf->sf_next)
1596 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1597 			psf->sf_oldin = mca_xcount ==
1598 				psf->sf_count[MCAST_EXCLUDE] &&
1599 				!psf->sf_count[MCAST_INCLUDE];
1600 		} else
1601 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1602 }
1603 
1604 static int sf_setstate(struct ip_mc_list *pmc)
1605 {
1606 	struct ip_sf_list *psf, *dpsf;
1607 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1608 	int qrv = pmc->interface->mr_qrv;
1609 	int new_in, rv;
1610 
1611 	rv = 0;
1612 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1613 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1614 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1615 				!psf->sf_count[MCAST_INCLUDE];
1616 		} else
1617 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1618 		if (new_in) {
1619 			if (!psf->sf_oldin) {
1620 				struct ip_sf_list *prev = NULL;
1621 
1622 				for (dpsf=pmc->tomb; dpsf; dpsf=dpsf->sf_next) {
1623 					if (dpsf->sf_inaddr == psf->sf_inaddr)
1624 						break;
1625 					prev = dpsf;
1626 				}
1627 				if (dpsf) {
1628 					if (prev)
1629 						prev->sf_next = dpsf->sf_next;
1630 					else
1631 						pmc->tomb = dpsf->sf_next;
1632 					kfree(dpsf);
1633 				}
1634 				psf->sf_crcount = qrv;
1635 				rv++;
1636 			}
1637 		} else if (psf->sf_oldin) {
1638 
1639 			psf->sf_crcount = 0;
1640 			/*
1641 			 * add or update "delete" records if an active filter
1642 			 * is now inactive
1643 			 */
1644 			for (dpsf=pmc->tomb; dpsf; dpsf=dpsf->sf_next)
1645 				if (dpsf->sf_inaddr == psf->sf_inaddr)
1646 					break;
1647 			if (!dpsf) {
1648 				dpsf = (struct ip_sf_list *)
1649 					kmalloc(sizeof(*dpsf), GFP_ATOMIC);
1650 				if (!dpsf)
1651 					continue;
1652 				*dpsf = *psf;
1653 				/* pmc->lock held by callers */
1654 				dpsf->sf_next = pmc->tomb;
1655 				pmc->tomb = dpsf;
1656 			}
1657 			dpsf->sf_crcount = qrv;
1658 			rv++;
1659 		}
1660 	}
1661 	return rv;
1662 }
1663 #endif
1664 
1665 /*
1666  * Add multicast source filter list to the interface list
1667  */
1668 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1669 			 int sfcount, __be32 *psfsrc, int delta)
1670 {
1671 	struct ip_mc_list *pmc;
1672 	int	isexclude;
1673 	int	i, err;
1674 
1675 	if (!in_dev)
1676 		return -ENODEV;
1677 	read_lock(&in_dev->mc_list_lock);
1678 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1679 		if (*pmca == pmc->multiaddr)
1680 			break;
1681 	}
1682 	if (!pmc) {
1683 		/* MCA not found?? bug */
1684 		read_unlock(&in_dev->mc_list_lock);
1685 		return -ESRCH;
1686 	}
1687 	spin_lock_bh(&pmc->lock);
1688 	read_unlock(&in_dev->mc_list_lock);
1689 
1690 #ifdef CONFIG_IP_MULTICAST
1691 	sf_markstate(pmc);
1692 #endif
1693 	isexclude = pmc->sfmode == MCAST_EXCLUDE;
1694 	if (!delta)
1695 		pmc->sfcount[sfmode]++;
1696 	err = 0;
1697 	for (i=0; i<sfcount; i++) {
1698 		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i], delta);
1699 		if (err)
1700 			break;
1701 	}
1702 	if (err) {
1703 		int j;
1704 
1705 		pmc->sfcount[sfmode]--;
1706 		for (j=0; j<i; j++)
1707 			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1708 	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
1709 #ifdef CONFIG_IP_MULTICAST
1710 		struct ip_sf_list *psf;
1711 		in_dev = pmc->interface;
1712 #endif
1713 
1714 		/* filter mode change */
1715 		if (pmc->sfcount[MCAST_EXCLUDE])
1716 			pmc->sfmode = MCAST_EXCLUDE;
1717 		else if (pmc->sfcount[MCAST_INCLUDE])
1718 			pmc->sfmode = MCAST_INCLUDE;
1719 #ifdef CONFIG_IP_MULTICAST
1720 		/* else no filters; keep old mode for reports */
1721 
1722 		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1723 			IGMP_Unsolicited_Report_Count;
1724 		in_dev->mr_ifc_count = pmc->crcount;
1725 		for (psf=pmc->sources; psf; psf = psf->sf_next)
1726 			psf->sf_crcount = 0;
1727 		igmp_ifc_event(in_dev);
1728 	} else if (sf_setstate(pmc)) {
1729 		igmp_ifc_event(in_dev);
1730 #endif
1731 	}
1732 	spin_unlock_bh(&pmc->lock);
1733 	return err;
1734 }
1735 
1736 static void ip_mc_clear_src(struct ip_mc_list *pmc)
1737 {
1738 	struct ip_sf_list *psf, *nextpsf;
1739 
1740 	for (psf=pmc->tomb; psf; psf=nextpsf) {
1741 		nextpsf = psf->sf_next;
1742 		kfree(psf);
1743 	}
1744 	pmc->tomb = NULL;
1745 	for (psf=pmc->sources; psf; psf=nextpsf) {
1746 		nextpsf = psf->sf_next;
1747 		kfree(psf);
1748 	}
1749 	pmc->sources = NULL;
1750 	pmc->sfmode = MCAST_EXCLUDE;
1751 	pmc->sfcount[MCAST_INCLUDE] = 0;
1752 	pmc->sfcount[MCAST_EXCLUDE] = 1;
1753 }
1754 
1755 
1756 /*
1757  * Join a multicast group
1758  */
1759 int ip_mc_join_group(struct sock *sk , struct ip_mreqn *imr)
1760 {
1761 	int err;
1762 	__be32 addr = imr->imr_multiaddr.s_addr;
1763 	struct ip_mc_socklist *iml = NULL, *i;
1764 	struct in_device *in_dev;
1765 	struct inet_sock *inet = inet_sk(sk);
1766 	struct net *net = sock_net(sk);
1767 	int ifindex;
1768 	int count = 0;
1769 
1770 	if (!ipv4_is_multicast(addr))
1771 		return -EINVAL;
1772 
1773 	rtnl_lock();
1774 
1775 	in_dev = ip_mc_find_dev(net, imr);
1776 
1777 	if (!in_dev) {
1778 		iml = NULL;
1779 		err = -ENODEV;
1780 		goto done;
1781 	}
1782 
1783 	err = -EADDRINUSE;
1784 	ifindex = imr->imr_ifindex;
1785 	for (i = inet->mc_list; i; i = i->next) {
1786 		if (i->multi.imr_multiaddr.s_addr == addr &&
1787 		    i->multi.imr_ifindex == ifindex)
1788 			goto done;
1789 		count++;
1790 	}
1791 	err = -ENOBUFS;
1792 	if (count >= sysctl_igmp_max_memberships)
1793 		goto done;
1794 	iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
1795 	if (iml == NULL)
1796 		goto done;
1797 
1798 	memcpy(&iml->multi, imr, sizeof(*imr));
1799 	iml->next = inet->mc_list;
1800 	iml->sflist = NULL;
1801 	iml->sfmode = MCAST_EXCLUDE;
1802 	inet->mc_list = iml;
1803 	ip_mc_inc_group(in_dev, addr);
1804 	err = 0;
1805 done:
1806 	rtnl_unlock();
1807 	return err;
1808 }
1809 
1810 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
1811 			   struct in_device *in_dev)
1812 {
1813 	int err;
1814 
1815 	if (iml->sflist == NULL) {
1816 		/* any-source empty exclude case */
1817 		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1818 			iml->sfmode, 0, NULL, 0);
1819 	}
1820 	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1821 			iml->sfmode, iml->sflist->sl_count,
1822 			iml->sflist->sl_addr, 0);
1823 	sock_kfree_s(sk, iml->sflist, IP_SFLSIZE(iml->sflist->sl_max));
1824 	iml->sflist = NULL;
1825 	return err;
1826 }
1827 
1828 /*
1829  *	Ask a socket to leave a group.
1830  */
1831 
1832 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
1833 {
1834 	struct inet_sock *inet = inet_sk(sk);
1835 	struct ip_mc_socklist *iml, **imlp;
1836 	struct in_device *in_dev;
1837 	struct net *net = sock_net(sk);
1838 	__be32 group = imr->imr_multiaddr.s_addr;
1839 	u32 ifindex;
1840 	int ret = -EADDRNOTAVAIL;
1841 
1842 	rtnl_lock();
1843 	in_dev = ip_mc_find_dev(net, imr);
1844 	ifindex = imr->imr_ifindex;
1845 	for (imlp = &inet->mc_list; (iml = *imlp) != NULL; imlp = &iml->next) {
1846 		if (iml->multi.imr_multiaddr.s_addr != group)
1847 			continue;
1848 		if (ifindex) {
1849 			if (iml->multi.imr_ifindex != ifindex)
1850 				continue;
1851 		} else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
1852 				iml->multi.imr_address.s_addr)
1853 			continue;
1854 
1855 		(void) ip_mc_leave_src(sk, iml, in_dev);
1856 
1857 		*imlp = iml->next;
1858 
1859 		if (in_dev)
1860 			ip_mc_dec_group(in_dev, group);
1861 		rtnl_unlock();
1862 		sock_kfree_s(sk, iml, sizeof(*iml));
1863 		return 0;
1864 	}
1865 	if (!in_dev)
1866 		ret = -ENODEV;
1867 	rtnl_unlock();
1868 	return ret;
1869 }
1870 
1871 int ip_mc_source(int add, int omode, struct sock *sk, struct
1872 	ip_mreq_source *mreqs, int ifindex)
1873 {
1874 	int err;
1875 	struct ip_mreqn imr;
1876 	__be32 addr = mreqs->imr_multiaddr;
1877 	struct ip_mc_socklist *pmc;
1878 	struct in_device *in_dev = NULL;
1879 	struct inet_sock *inet = inet_sk(sk);
1880 	struct ip_sf_socklist *psl;
1881 	struct net *net = sock_net(sk);
1882 	int leavegroup = 0;
1883 	int i, j, rv;
1884 
1885 	if (!ipv4_is_multicast(addr))
1886 		return -EINVAL;
1887 
1888 	rtnl_lock();
1889 
1890 	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
1891 	imr.imr_address.s_addr = mreqs->imr_interface;
1892 	imr.imr_ifindex = ifindex;
1893 	in_dev = ip_mc_find_dev(net, &imr);
1894 
1895 	if (!in_dev) {
1896 		err = -ENODEV;
1897 		goto done;
1898 	}
1899 	err = -EADDRNOTAVAIL;
1900 
1901 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
1902 		if ((pmc->multi.imr_multiaddr.s_addr ==
1903 		     imr.imr_multiaddr.s_addr) &&
1904 		    (pmc->multi.imr_ifindex == imr.imr_ifindex))
1905 			break;
1906 	}
1907 	if (!pmc) {		/* must have a prior join */
1908 		err = -EINVAL;
1909 		goto done;
1910 	}
1911 	/* if a source filter was set, must be the same mode as before */
1912 	if (pmc->sflist) {
1913 		if (pmc->sfmode != omode) {
1914 			err = -EINVAL;
1915 			goto done;
1916 		}
1917 	} else if (pmc->sfmode != omode) {
1918 		/* allow mode switches for empty-set filters */
1919 		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
1920 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
1921 			NULL, 0);
1922 		pmc->sfmode = omode;
1923 	}
1924 
1925 	psl = pmc->sflist;
1926 	if (!add) {
1927 		if (!psl)
1928 			goto done;	/* err = -EADDRNOTAVAIL */
1929 		rv = !0;
1930 		for (i=0; i<psl->sl_count; i++) {
1931 			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1932 				sizeof(__be32));
1933 			if (rv == 0)
1934 				break;
1935 		}
1936 		if (rv)		/* source not found */
1937 			goto done;	/* err = -EADDRNOTAVAIL */
1938 
1939 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
1940 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
1941 			leavegroup = 1;
1942 			goto done;
1943 		}
1944 
1945 		/* update the interface filter */
1946 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1947 			&mreqs->imr_sourceaddr, 1);
1948 
1949 		for (j=i+1; j<psl->sl_count; j++)
1950 			psl->sl_addr[j-1] = psl->sl_addr[j];
1951 		psl->sl_count--;
1952 		err = 0;
1953 		goto done;
1954 	}
1955 	/* else, add a new source to the filter */
1956 
1957 	if (psl && psl->sl_count >= sysctl_igmp_max_msf) {
1958 		err = -ENOBUFS;
1959 		goto done;
1960 	}
1961 	if (!psl || psl->sl_count == psl->sl_max) {
1962 		struct ip_sf_socklist *newpsl;
1963 		int count = IP_SFBLOCK;
1964 
1965 		if (psl)
1966 			count += psl->sl_max;
1967 		newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
1968 		if (!newpsl) {
1969 			err = -ENOBUFS;
1970 			goto done;
1971 		}
1972 		newpsl->sl_max = count;
1973 		newpsl->sl_count = count - IP_SFBLOCK;
1974 		if (psl) {
1975 			for (i=0; i<psl->sl_count; i++)
1976 				newpsl->sl_addr[i] = psl->sl_addr[i];
1977 			sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
1978 		}
1979 		pmc->sflist = psl = newpsl;
1980 	}
1981 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
1982 	for (i=0; i<psl->sl_count; i++) {
1983 		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1984 			sizeof(__be32));
1985 		if (rv == 0)
1986 			break;
1987 	}
1988 	if (rv == 0)		/* address already there is an error */
1989 		goto done;
1990 	for (j=psl->sl_count-1; j>=i; j--)
1991 		psl->sl_addr[j+1] = psl->sl_addr[j];
1992 	psl->sl_addr[i] = mreqs->imr_sourceaddr;
1993 	psl->sl_count++;
1994 	err = 0;
1995 	/* update the interface list */
1996 	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1997 		&mreqs->imr_sourceaddr, 1);
1998 done:
1999 	rtnl_unlock();
2000 	if (leavegroup)
2001 		return ip_mc_leave_group(sk, &imr);
2002 	return err;
2003 }
2004 
2005 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2006 {
2007 	int err = 0;
2008 	struct ip_mreqn	imr;
2009 	__be32 addr = msf->imsf_multiaddr;
2010 	struct ip_mc_socklist *pmc;
2011 	struct in_device *in_dev;
2012 	struct inet_sock *inet = inet_sk(sk);
2013 	struct ip_sf_socklist *newpsl, *psl;
2014 	struct net *net = sock_net(sk);
2015 	int leavegroup = 0;
2016 
2017 	if (!ipv4_is_multicast(addr))
2018 		return -EINVAL;
2019 	if (msf->imsf_fmode != MCAST_INCLUDE &&
2020 	    msf->imsf_fmode != MCAST_EXCLUDE)
2021 		return -EINVAL;
2022 
2023 	rtnl_lock();
2024 
2025 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2026 	imr.imr_address.s_addr = msf->imsf_interface;
2027 	imr.imr_ifindex = ifindex;
2028 	in_dev = ip_mc_find_dev(net, &imr);
2029 
2030 	if (!in_dev) {
2031 		err = -ENODEV;
2032 		goto done;
2033 	}
2034 
2035 	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2036 	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2037 		leavegroup = 1;
2038 		goto done;
2039 	}
2040 
2041 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2042 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2043 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2044 			break;
2045 	}
2046 	if (!pmc) {		/* must have a prior join */
2047 		err = -EINVAL;
2048 		goto done;
2049 	}
2050 	if (msf->imsf_numsrc) {
2051 		newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2052 							   GFP_KERNEL);
2053 		if (!newpsl) {
2054 			err = -ENOBUFS;
2055 			goto done;
2056 		}
2057 		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2058 		memcpy(newpsl->sl_addr, msf->imsf_slist,
2059 			msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2060 		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2061 			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2062 		if (err) {
2063 			sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2064 			goto done;
2065 		}
2066 	} else {
2067 		newpsl = NULL;
2068 		(void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2069 				     msf->imsf_fmode, 0, NULL, 0);
2070 	}
2071 	psl = pmc->sflist;
2072 	if (psl) {
2073 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2074 			psl->sl_count, psl->sl_addr, 0);
2075 		sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
2076 	} else
2077 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2078 			0, NULL, 0);
2079 	pmc->sflist = newpsl;
2080 	pmc->sfmode = msf->imsf_fmode;
2081 	err = 0;
2082 done:
2083 	rtnl_unlock();
2084 	if (leavegroup)
2085 		err = ip_mc_leave_group(sk, &imr);
2086 	return err;
2087 }
2088 
2089 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2090 	struct ip_msfilter __user *optval, int __user *optlen)
2091 {
2092 	int err, len, count, copycount;
2093 	struct ip_mreqn	imr;
2094 	__be32 addr = msf->imsf_multiaddr;
2095 	struct ip_mc_socklist *pmc;
2096 	struct in_device *in_dev;
2097 	struct inet_sock *inet = inet_sk(sk);
2098 	struct ip_sf_socklist *psl;
2099 	struct net *net = sock_net(sk);
2100 
2101 	if (!ipv4_is_multicast(addr))
2102 		return -EINVAL;
2103 
2104 	rtnl_lock();
2105 
2106 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2107 	imr.imr_address.s_addr = msf->imsf_interface;
2108 	imr.imr_ifindex = 0;
2109 	in_dev = ip_mc_find_dev(net, &imr);
2110 
2111 	if (!in_dev) {
2112 		err = -ENODEV;
2113 		goto done;
2114 	}
2115 	err = -EADDRNOTAVAIL;
2116 
2117 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2118 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2119 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2120 			break;
2121 	}
2122 	if (!pmc)		/* must have a prior join */
2123 		goto done;
2124 	msf->imsf_fmode = pmc->sfmode;
2125 	psl = pmc->sflist;
2126 	rtnl_unlock();
2127 	if (!psl) {
2128 		len = 0;
2129 		count = 0;
2130 	} else {
2131 		count = psl->sl_count;
2132 	}
2133 	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2134 	len = copycount * sizeof(psl->sl_addr[0]);
2135 	msf->imsf_numsrc = count;
2136 	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2137 	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2138 		return -EFAULT;
2139 	}
2140 	if (len &&
2141 	    copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2142 		return -EFAULT;
2143 	return 0;
2144 done:
2145 	rtnl_unlock();
2146 	return err;
2147 }
2148 
2149 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2150 	struct group_filter __user *optval, int __user *optlen)
2151 {
2152 	int err, i, count, copycount;
2153 	struct sockaddr_in *psin;
2154 	__be32 addr;
2155 	struct ip_mc_socklist *pmc;
2156 	struct inet_sock *inet = inet_sk(sk);
2157 	struct ip_sf_socklist *psl;
2158 
2159 	psin = (struct sockaddr_in *)&gsf->gf_group;
2160 	if (psin->sin_family != AF_INET)
2161 		return -EINVAL;
2162 	addr = psin->sin_addr.s_addr;
2163 	if (!ipv4_is_multicast(addr))
2164 		return -EINVAL;
2165 
2166 	rtnl_lock();
2167 
2168 	err = -EADDRNOTAVAIL;
2169 
2170 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2171 		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2172 		    pmc->multi.imr_ifindex == gsf->gf_interface)
2173 			break;
2174 	}
2175 	if (!pmc)		/* must have a prior join */
2176 		goto done;
2177 	gsf->gf_fmode = pmc->sfmode;
2178 	psl = pmc->sflist;
2179 	rtnl_unlock();
2180 	count = psl ? psl->sl_count : 0;
2181 	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2182 	gsf->gf_numsrc = count;
2183 	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2184 	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2185 		return -EFAULT;
2186 	}
2187 	for (i=0; i<copycount; i++) {
2188 		struct sockaddr_storage ss;
2189 
2190 		psin = (struct sockaddr_in *)&ss;
2191 		memset(&ss, 0, sizeof(ss));
2192 		psin->sin_family = AF_INET;
2193 		psin->sin_addr.s_addr = psl->sl_addr[i];
2194 		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2195 			return -EFAULT;
2196 	}
2197 	return 0;
2198 done:
2199 	rtnl_unlock();
2200 	return err;
2201 }
2202 
2203 /*
2204  * check if a multicast source filter allows delivery for a given <src,dst,intf>
2205  */
2206 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif)
2207 {
2208 	struct inet_sock *inet = inet_sk(sk);
2209 	struct ip_mc_socklist *pmc;
2210 	struct ip_sf_socklist *psl;
2211 	int i;
2212 
2213 	if (!ipv4_is_multicast(loc_addr))
2214 		return 1;
2215 
2216 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2217 		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2218 		    pmc->multi.imr_ifindex == dif)
2219 			break;
2220 	}
2221 	if (!pmc)
2222 		return inet->mc_all;
2223 	psl = pmc->sflist;
2224 	if (!psl)
2225 		return pmc->sfmode == MCAST_EXCLUDE;
2226 
2227 	for (i=0; i<psl->sl_count; i++) {
2228 		if (psl->sl_addr[i] == rmt_addr)
2229 			break;
2230 	}
2231 	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2232 		return 0;
2233 	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2234 		return 0;
2235 	return 1;
2236 }
2237 
2238 /*
2239  *	A socket is closing.
2240  */
2241 
2242 void ip_mc_drop_socket(struct sock *sk)
2243 {
2244 	struct inet_sock *inet = inet_sk(sk);
2245 	struct ip_mc_socklist *iml;
2246 	struct net *net = sock_net(sk);
2247 
2248 	if (inet->mc_list == NULL)
2249 		return;
2250 
2251 	rtnl_lock();
2252 	while ((iml = inet->mc_list) != NULL) {
2253 		struct in_device *in_dev;
2254 		inet->mc_list = iml->next;
2255 
2256 		in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2257 		(void) ip_mc_leave_src(sk, iml, in_dev);
2258 		if (in_dev != NULL) {
2259 			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2260 			in_dev_put(in_dev);
2261 		}
2262 		sock_kfree_s(sk, iml, sizeof(*iml));
2263 	}
2264 	rtnl_unlock();
2265 }
2266 
2267 int ip_check_mc(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u16 proto)
2268 {
2269 	struct ip_mc_list *im;
2270 	struct ip_sf_list *psf;
2271 	int rv = 0;
2272 
2273 	read_lock(&in_dev->mc_list_lock);
2274 	for (im=in_dev->mc_list; im; im=im->next) {
2275 		if (im->multiaddr == mc_addr)
2276 			break;
2277 	}
2278 	if (im && proto == IPPROTO_IGMP) {
2279 		rv = 1;
2280 	} else if (im) {
2281 		if (src_addr) {
2282 			for (psf=im->sources; psf; psf=psf->sf_next) {
2283 				if (psf->sf_inaddr == src_addr)
2284 					break;
2285 			}
2286 			if (psf)
2287 				rv = psf->sf_count[MCAST_INCLUDE] ||
2288 					psf->sf_count[MCAST_EXCLUDE] !=
2289 					im->sfcount[MCAST_EXCLUDE];
2290 			else
2291 				rv = im->sfcount[MCAST_EXCLUDE] != 0;
2292 		} else
2293 			rv = 1; /* unspecified source; tentatively allow */
2294 	}
2295 	read_unlock(&in_dev->mc_list_lock);
2296 	return rv;
2297 }
2298 
2299 #if defined(CONFIG_PROC_FS)
2300 struct igmp_mc_iter_state {
2301 	struct seq_net_private p;
2302 	struct net_device *dev;
2303 	struct in_device *in_dev;
2304 };
2305 
2306 #define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2307 
2308 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2309 {
2310 	struct net *net = seq_file_net(seq);
2311 	struct ip_mc_list *im = NULL;
2312 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2313 
2314 	state->in_dev = NULL;
2315 	for_each_netdev_rcu(net, state->dev) {
2316 		struct in_device *in_dev;
2317 
2318 		in_dev = __in_dev_get_rcu(state->dev);
2319 		if (!in_dev)
2320 			continue;
2321 		read_lock(&in_dev->mc_list_lock);
2322 		im = in_dev->mc_list;
2323 		if (im) {
2324 			state->in_dev = in_dev;
2325 			break;
2326 		}
2327 		read_unlock(&in_dev->mc_list_lock);
2328 	}
2329 	return im;
2330 }
2331 
2332 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2333 {
2334 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2335 	im = im->next;
2336 	while (!im) {
2337 		if (likely(state->in_dev != NULL))
2338 			read_unlock(&state->in_dev->mc_list_lock);
2339 
2340 		state->dev = next_net_device_rcu(state->dev);
2341 		if (!state->dev) {
2342 			state->in_dev = NULL;
2343 			break;
2344 		}
2345 		state->in_dev = __in_dev_get_rcu(state->dev);
2346 		if (!state->in_dev)
2347 			continue;
2348 		read_lock(&state->in_dev->mc_list_lock);
2349 		im = state->in_dev->mc_list;
2350 	}
2351 	return im;
2352 }
2353 
2354 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2355 {
2356 	struct ip_mc_list *im = igmp_mc_get_first(seq);
2357 	if (im)
2358 		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2359 			--pos;
2360 	return pos ? NULL : im;
2361 }
2362 
2363 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2364 	__acquires(rcu)
2365 {
2366 	rcu_read_lock();
2367 	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2368 }
2369 
2370 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2371 {
2372 	struct ip_mc_list *im;
2373 	if (v == SEQ_START_TOKEN)
2374 		im = igmp_mc_get_first(seq);
2375 	else
2376 		im = igmp_mc_get_next(seq, v);
2377 	++*pos;
2378 	return im;
2379 }
2380 
2381 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2382 	__releases(rcu)
2383 {
2384 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2385 	if (likely(state->in_dev != NULL)) {
2386 		read_unlock(&state->in_dev->mc_list_lock);
2387 		state->in_dev = NULL;
2388 	}
2389 	state->dev = NULL;
2390 	rcu_read_unlock();
2391 }
2392 
2393 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2394 {
2395 	if (v == SEQ_START_TOKEN)
2396 		seq_puts(seq,
2397 			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2398 	else {
2399 		struct ip_mc_list *im = (struct ip_mc_list *)v;
2400 		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2401 		char   *querier;
2402 #ifdef CONFIG_IP_MULTICAST
2403 		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2404 			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2405 			  "V3";
2406 #else
2407 		querier = "NONE";
2408 #endif
2409 
2410 		if (state->in_dev->mc_list == im) {
2411 			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2412 				   state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2413 		}
2414 
2415 		seq_printf(seq,
2416 			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2417 			   im->multiaddr, im->users,
2418 			   im->tm_running, im->tm_running ?
2419 			   jiffies_to_clock_t(im->timer.expires-jiffies) : 0,
2420 			   im->reporter);
2421 	}
2422 	return 0;
2423 }
2424 
2425 static const struct seq_operations igmp_mc_seq_ops = {
2426 	.start	=	igmp_mc_seq_start,
2427 	.next	=	igmp_mc_seq_next,
2428 	.stop	=	igmp_mc_seq_stop,
2429 	.show	=	igmp_mc_seq_show,
2430 };
2431 
2432 static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2433 {
2434 	return seq_open_net(inode, file, &igmp_mc_seq_ops,
2435 			sizeof(struct igmp_mc_iter_state));
2436 }
2437 
2438 static const struct file_operations igmp_mc_seq_fops = {
2439 	.owner		=	THIS_MODULE,
2440 	.open		=	igmp_mc_seq_open,
2441 	.read		=	seq_read,
2442 	.llseek		=	seq_lseek,
2443 	.release	=	seq_release_net,
2444 };
2445 
2446 struct igmp_mcf_iter_state {
2447 	struct seq_net_private p;
2448 	struct net_device *dev;
2449 	struct in_device *idev;
2450 	struct ip_mc_list *im;
2451 };
2452 
2453 #define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2454 
2455 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2456 {
2457 	struct net *net = seq_file_net(seq);
2458 	struct ip_sf_list *psf = NULL;
2459 	struct ip_mc_list *im = NULL;
2460 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2461 
2462 	state->idev = NULL;
2463 	state->im = NULL;
2464 	for_each_netdev_rcu(net, state->dev) {
2465 		struct in_device *idev;
2466 		idev = __in_dev_get_rcu(state->dev);
2467 		if (unlikely(idev == NULL))
2468 			continue;
2469 		read_lock(&idev->mc_list_lock);
2470 		im = idev->mc_list;
2471 		if (likely(im != NULL)) {
2472 			spin_lock_bh(&im->lock);
2473 			psf = im->sources;
2474 			if (likely(psf != NULL)) {
2475 				state->im = im;
2476 				state->idev = idev;
2477 				break;
2478 			}
2479 			spin_unlock_bh(&im->lock);
2480 		}
2481 		read_unlock(&idev->mc_list_lock);
2482 	}
2483 	return psf;
2484 }
2485 
2486 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2487 {
2488 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2489 
2490 	psf = psf->sf_next;
2491 	while (!psf) {
2492 		spin_unlock_bh(&state->im->lock);
2493 		state->im = state->im->next;
2494 		while (!state->im) {
2495 			if (likely(state->idev != NULL))
2496 				read_unlock(&state->idev->mc_list_lock);
2497 
2498 			state->dev = next_net_device_rcu(state->dev);
2499 			if (!state->dev) {
2500 				state->idev = NULL;
2501 				goto out;
2502 			}
2503 			state->idev = __in_dev_get_rcu(state->dev);
2504 			if (!state->idev)
2505 				continue;
2506 			read_lock(&state->idev->mc_list_lock);
2507 			state->im = state->idev->mc_list;
2508 		}
2509 		if (!state->im)
2510 			break;
2511 		spin_lock_bh(&state->im->lock);
2512 		psf = state->im->sources;
2513 	}
2514 out:
2515 	return psf;
2516 }
2517 
2518 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2519 {
2520 	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2521 	if (psf)
2522 		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2523 			--pos;
2524 	return pos ? NULL : psf;
2525 }
2526 
2527 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2528 	__acquires(rcu)
2529 {
2530 	rcu_read_lock();
2531 	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2532 }
2533 
2534 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2535 {
2536 	struct ip_sf_list *psf;
2537 	if (v == SEQ_START_TOKEN)
2538 		psf = igmp_mcf_get_first(seq);
2539 	else
2540 		psf = igmp_mcf_get_next(seq, v);
2541 	++*pos;
2542 	return psf;
2543 }
2544 
2545 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2546 	__releases(rcu)
2547 {
2548 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2549 	if (likely(state->im != NULL)) {
2550 		spin_unlock_bh(&state->im->lock);
2551 		state->im = NULL;
2552 	}
2553 	if (likely(state->idev != NULL)) {
2554 		read_unlock(&state->idev->mc_list_lock);
2555 		state->idev = NULL;
2556 	}
2557 	state->dev = NULL;
2558 	rcu_read_unlock();
2559 }
2560 
2561 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2562 {
2563 	struct ip_sf_list *psf = (struct ip_sf_list *)v;
2564 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2565 
2566 	if (v == SEQ_START_TOKEN) {
2567 		seq_printf(seq,
2568 			   "%3s %6s "
2569 			   "%10s %10s %6s %6s\n", "Idx",
2570 			   "Device", "MCA",
2571 			   "SRC", "INC", "EXC");
2572 	} else {
2573 		seq_printf(seq,
2574 			   "%3d %6.6s 0x%08x "
2575 			   "0x%08x %6lu %6lu\n",
2576 			   state->dev->ifindex, state->dev->name,
2577 			   ntohl(state->im->multiaddr),
2578 			   ntohl(psf->sf_inaddr),
2579 			   psf->sf_count[MCAST_INCLUDE],
2580 			   psf->sf_count[MCAST_EXCLUDE]);
2581 	}
2582 	return 0;
2583 }
2584 
2585 static const struct seq_operations igmp_mcf_seq_ops = {
2586 	.start	=	igmp_mcf_seq_start,
2587 	.next	=	igmp_mcf_seq_next,
2588 	.stop	=	igmp_mcf_seq_stop,
2589 	.show	=	igmp_mcf_seq_show,
2590 };
2591 
2592 static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2593 {
2594 	return seq_open_net(inode, file, &igmp_mcf_seq_ops,
2595 			sizeof(struct igmp_mcf_iter_state));
2596 }
2597 
2598 static const struct file_operations igmp_mcf_seq_fops = {
2599 	.owner		=	THIS_MODULE,
2600 	.open		=	igmp_mcf_seq_open,
2601 	.read		=	seq_read,
2602 	.llseek		=	seq_lseek,
2603 	.release	=	seq_release_net,
2604 };
2605 
2606 static int igmp_net_init(struct net *net)
2607 {
2608 	struct proc_dir_entry *pde;
2609 
2610 	pde = proc_net_fops_create(net, "igmp", S_IRUGO, &igmp_mc_seq_fops);
2611 	if (!pde)
2612 		goto out_igmp;
2613 	pde = proc_net_fops_create(net, "mcfilter", S_IRUGO, &igmp_mcf_seq_fops);
2614 	if (!pde)
2615 		goto out_mcfilter;
2616 	return 0;
2617 
2618 out_mcfilter:
2619 	proc_net_remove(net, "igmp");
2620 out_igmp:
2621 	return -ENOMEM;
2622 }
2623 
2624 static void igmp_net_exit(struct net *net)
2625 {
2626 	proc_net_remove(net, "mcfilter");
2627 	proc_net_remove(net, "igmp");
2628 }
2629 
2630 static struct pernet_operations igmp_net_ops = {
2631 	.init = igmp_net_init,
2632 	.exit = igmp_net_exit,
2633 };
2634 
2635 int __init igmp_mc_proc_init(void)
2636 {
2637 	return register_pernet_subsys(&igmp_net_ops);
2638 }
2639 #endif
2640 
2641 EXPORT_SYMBOL(ip_mc_dec_group);
2642 EXPORT_SYMBOL(ip_mc_inc_group);
2643 EXPORT_SYMBOL(ip_mc_join_group);
2644 EXPORT_SYMBOL(ip_mc_rejoin_group);
2645