xref: /linux/net/ipv4/igmp.c (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
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  *	Version: $Id: igmp.c,v 1.47 2002/02/01 22:01:03 davem Exp $
12  *
13  *	Authors:
14  *		Alan Cox <Alan.Cox@linux.org>
15  *
16  *	This program is free software; you can redistribute it and/or
17  *	modify it under the terms of the GNU General Public License
18  *	as published by the Free Software Foundation; either version
19  *	2 of the License, or (at your option) any later version.
20  *
21  *	Fixes:
22  *
23  *		Alan Cox	:	Added lots of __inline__ to optimise
24  *					the memory usage of all the tiny little
25  *					functions.
26  *		Alan Cox	:	Dumped the header building experiment.
27  *		Alan Cox	:	Minor tweaks ready for multicast routing
28  *					and extended IGMP protocol.
29  *		Alan Cox	:	Removed a load of inline directives. Gcc 2.5.8
30  *					writes utterly bogus code otherwise (sigh)
31  *					fixed IGMP loopback to behave in the manner
32  *					desired by mrouted, fixed the fact it has been
33  *					broken since 1.3.6 and cleaned up a few minor
34  *					points.
35  *
36  *		Chih-Jen Chang	:	Tried to revise IGMP to Version 2
37  *		Tsu-Sheng Tsao		E-mail: chihjenc@scf.usc.edu and tsusheng@scf.usc.edu
38  *					The enhancements are mainly based on Steve Deering's
39  * 					ipmulti-3.5 source code.
40  *		Chih-Jen Chang	:	Added the igmp_get_mrouter_info and
41  *		Tsu-Sheng Tsao		igmp_set_mrouter_info to keep track of
42  *					the mrouted version on that device.
43  *		Chih-Jen Chang	:	Added the max_resp_time parameter to
44  *		Tsu-Sheng Tsao		igmp_heard_query(). Using this parameter
45  *					to identify the multicast router version
46  *					and do what the IGMP version 2 specified.
47  *		Chih-Jen Chang	:	Added a timer to revert to IGMP V2 router
48  *		Tsu-Sheng Tsao		if the specified time expired.
49  *		Alan Cox	:	Stop IGMP from 0.0.0.0 being accepted.
50  *		Alan Cox	:	Use GFP_ATOMIC in the right places.
51  *		Christian Daudt :	igmp timer wasn't set for local group
52  *					memberships but was being deleted,
53  *					which caused a "del_timer() called
54  *					from %p with timer not initialized\n"
55  *					message (960131).
56  *		Christian Daudt :	removed del_timer from
57  *					igmp_timer_expire function (960205).
58  *             Christian Daudt :       igmp_heard_report now only calls
59  *                                     igmp_timer_expire if tm->running is
60  *                                     true (960216).
61  *		Malcolm Beattie :	ttl comparison wrong in igmp_rcv made
62  *					igmp_heard_query never trigger. Expiry
63  *					miscalculation fixed in igmp_heard_query
64  *					and random() made to return unsigned to
65  *					prevent negative expiry times.
66  *		Alexey Kuznetsov:	Wrong group leaving behaviour, backport
67  *					fix from pending 2.1.x patches.
68  *		Alan Cox:		Forget to enable FDDI support earlier.
69  *		Alexey Kuznetsov:	Fixed leaving groups on device down.
70  *		Alexey Kuznetsov:	Accordance to igmp-v2-06 draft.
71  *		David L Stevens:	IGMPv3 support, with help from
72  *					Vinay Kulkarni
73  */
74 
75 #include <linux/module.h>
76 #include <asm/uaccess.h>
77 #include <asm/system.h>
78 #include <linux/types.h>
79 #include <linux/kernel.h>
80 #include <linux/jiffies.h>
81 #include <linux/string.h>
82 #include <linux/socket.h>
83 #include <linux/sockios.h>
84 #include <linux/in.h>
85 #include <linux/inet.h>
86 #include <linux/netdevice.h>
87 #include <linux/skbuff.h>
88 #include <linux/inetdevice.h>
89 #include <linux/igmp.h>
90 #include <linux/if_arp.h>
91 #include <linux/rtnetlink.h>
92 #include <linux/times.h>
93 
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 <linux/netfilter_ipv4.h>
101 #ifdef CONFIG_IP_MROUTE
102 #include <linux/mroute.h>
103 #endif
104 #ifdef CONFIG_PROC_FS
105 #include <linux/proc_fs.h>
106 #include <linux/seq_file.h>
107 #endif
108 
109 #define IP_MAX_MEMBERSHIPS	20
110 #define IP_MAX_MSF		10
111 
112 #ifdef CONFIG_IP_MULTICAST
113 /* Parameter names and values are taken from igmp-v2-06 draft */
114 
115 #define IGMP_V1_Router_Present_Timeout		(400*HZ)
116 #define IGMP_V2_Router_Present_Timeout		(400*HZ)
117 #define IGMP_Unsolicited_Report_Interval	(10*HZ)
118 #define IGMP_Query_Response_Interval		(10*HZ)
119 #define IGMP_Unsolicited_Report_Count		2
120 
121 
122 #define IGMP_Initial_Report_Delay		(1)
123 
124 /* IGMP_Initial_Report_Delay is not from IGMP specs!
125  * IGMP specs require to report membership immediately after
126  * joining a group, but we delay the first report by a
127  * small interval. It seems more natural and still does not
128  * contradict to specs provided this delay is small enough.
129  */
130 
131 #define IGMP_V1_SEEN(in_dev) (ipv4_devconf.force_igmp_version == 1 || \
132 		(in_dev)->cnf.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) (ipv4_devconf.force_igmp_version == 2 || \
136 		(in_dev)->cnf.force_igmp_version == 2 || \
137 		((in_dev)->mr_v2_seen && \
138 		time_before(jiffies, (in_dev)->mr_v2_seen)))
139 
140 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im);
141 static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr);
142 static void igmpv3_clear_delrec(struct in_device *in_dev);
143 static int sf_setstate(struct ip_mc_list *pmc);
144 static void sf_markstate(struct ip_mc_list *pmc);
145 #endif
146 static void ip_mc_clear_src(struct ip_mc_list *pmc);
147 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
148 			 int sfcount, __be32 *psfsrc, int delta);
149 
150 static void ip_ma_put(struct ip_mc_list *im)
151 {
152 	if (atomic_dec_and_test(&im->refcnt)) {
153 		in_dev_put(im->interface);
154 		kfree(im);
155 	}
156 }
157 
158 #ifdef CONFIG_IP_MULTICAST
159 
160 /*
161  *	Timer management
162  */
163 
164 static __inline__ void igmp_stop_timer(struct ip_mc_list *im)
165 {
166 	spin_lock_bh(&im->lock);
167 	if (del_timer(&im->timer))
168 		atomic_dec(&im->refcnt);
169 	im->tm_running=0;
170 	im->reporter = 0;
171 	im->unsolicit_count = 0;
172 	spin_unlock_bh(&im->lock);
173 }
174 
175 /* It must be called with locked im->lock */
176 static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
177 {
178 	int tv=net_random() % max_delay;
179 
180 	im->tm_running=1;
181 	if (!mod_timer(&im->timer, jiffies+tv+2))
182 		atomic_inc(&im->refcnt);
183 }
184 
185 static void igmp_gq_start_timer(struct in_device *in_dev)
186 {
187 	int tv = net_random() % in_dev->mr_maxdelay;
188 
189 	in_dev->mr_gq_running = 1;
190 	if (!mod_timer(&in_dev->mr_gq_timer, jiffies+tv+2))
191 		in_dev_hold(in_dev);
192 }
193 
194 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
195 {
196 	int tv = net_random() % delay;
197 
198 	if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
199 		in_dev_hold(in_dev);
200 }
201 
202 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
203 {
204 	spin_lock_bh(&im->lock);
205 	im->unsolicit_count = 0;
206 	if (del_timer(&im->timer)) {
207 		if ((long)(im->timer.expires-jiffies) < max_delay) {
208 			add_timer(&im->timer);
209 			im->tm_running=1;
210 			spin_unlock_bh(&im->lock);
211 			return;
212 		}
213 		atomic_dec(&im->refcnt);
214 	}
215 	igmp_start_timer(im, max_delay);
216 	spin_unlock_bh(&im->lock);
217 }
218 
219 
220 /*
221  *	Send an IGMP report.
222  */
223 
224 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
225 
226 
227 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
228 	int gdeleted, int sdeleted)
229 {
230 	switch (type) {
231 	case IGMPV3_MODE_IS_INCLUDE:
232 	case IGMPV3_MODE_IS_EXCLUDE:
233 		if (gdeleted || sdeleted)
234 			return 0;
235 		if (!(pmc->gsquery && !psf->sf_gsresp)) {
236 			if (pmc->sfmode == MCAST_INCLUDE)
237 				return 1;
238 			/* don't include if this source is excluded
239 			 * in all filters
240 			 */
241 			if (psf->sf_count[MCAST_INCLUDE])
242 				return type == IGMPV3_MODE_IS_INCLUDE;
243 			return pmc->sfcount[MCAST_EXCLUDE] ==
244 				psf->sf_count[MCAST_EXCLUDE];
245 		}
246 		return 0;
247 	case IGMPV3_CHANGE_TO_INCLUDE:
248 		if (gdeleted || sdeleted)
249 			return 0;
250 		return psf->sf_count[MCAST_INCLUDE] != 0;
251 	case IGMPV3_CHANGE_TO_EXCLUDE:
252 		if (gdeleted || sdeleted)
253 			return 0;
254 		if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
255 		    psf->sf_count[MCAST_INCLUDE])
256 			return 0;
257 		return pmc->sfcount[MCAST_EXCLUDE] ==
258 			psf->sf_count[MCAST_EXCLUDE];
259 	case IGMPV3_ALLOW_NEW_SOURCES:
260 		if (gdeleted || !psf->sf_crcount)
261 			return 0;
262 		return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
263 	case IGMPV3_BLOCK_OLD_SOURCES:
264 		if (pmc->sfmode == MCAST_INCLUDE)
265 			return gdeleted || (psf->sf_crcount && sdeleted);
266 		return psf->sf_crcount && !gdeleted && !sdeleted;
267 	}
268 	return 0;
269 }
270 
271 static int
272 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
273 {
274 	struct ip_sf_list *psf;
275 	int scount = 0;
276 
277 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
278 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
279 			continue;
280 		scount++;
281 	}
282 	return scount;
283 }
284 
285 static struct sk_buff *igmpv3_newpack(struct net_device *dev, int size)
286 {
287 	struct sk_buff *skb;
288 	struct rtable *rt;
289 	struct iphdr *pip;
290 	struct igmpv3_report *pig;
291 
292 	skb = alloc_skb(size + LL_RESERVED_SPACE(dev), GFP_ATOMIC);
293 	if (skb == NULL)
294 		return NULL;
295 
296 	{
297 		struct flowi fl = { .oif = dev->ifindex,
298 				    .nl_u = { .ip4_u = {
299 				    .daddr = IGMPV3_ALL_MCR } },
300 				    .proto = IPPROTO_IGMP };
301 		if (ip_route_output_key(&rt, &fl)) {
302 			kfree_skb(skb);
303 			return NULL;
304 		}
305 	}
306 	if (rt->rt_src == 0) {
307 		kfree_skb(skb);
308 		ip_rt_put(rt);
309 		return NULL;
310 	}
311 
312 	skb->dst = &rt->u.dst;
313 	skb->dev = dev;
314 
315 	skb_reserve(skb, LL_RESERVED_SPACE(dev));
316 
317 	skb->nh.iph = pip =(struct iphdr *)skb_put(skb, sizeof(struct iphdr)+4);
318 
319 	pip->version  = 4;
320 	pip->ihl      = (sizeof(struct iphdr)+4)>>2;
321 	pip->tos      = 0xc0;
322 	pip->frag_off = htons(IP_DF);
323 	pip->ttl      = 1;
324 	pip->daddr    = rt->rt_dst;
325 	pip->saddr    = rt->rt_src;
326 	pip->protocol = IPPROTO_IGMP;
327 	pip->tot_len  = 0;	/* filled in later */
328 	ip_select_ident(pip, &rt->u.dst, NULL);
329 	((u8*)&pip[1])[0] = IPOPT_RA;
330 	((u8*)&pip[1])[1] = 4;
331 	((u8*)&pip[1])[2] = 0;
332 	((u8*)&pip[1])[3] = 0;
333 
334 	pig =(struct igmpv3_report *)skb_put(skb, sizeof(*pig));
335 	skb->h.igmph = (struct igmphdr *)pig;
336 	pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
337 	pig->resv1 = 0;
338 	pig->csum = 0;
339 	pig->resv2 = 0;
340 	pig->ngrec = 0;
341 	return skb;
342 }
343 
344 static int igmpv3_sendpack(struct sk_buff *skb)
345 {
346 	struct iphdr *pip = skb->nh.iph;
347 	struct igmphdr *pig = skb->h.igmph;
348 	int iplen, igmplen;
349 
350 	iplen = skb->tail - (unsigned char *)skb->nh.iph;
351 	pip->tot_len = htons(iplen);
352 	ip_send_check(pip);
353 
354 	igmplen = skb->tail - (unsigned char *)skb->h.igmph;
355 	pig->csum = ip_compute_csum((void *)skb->h.igmph, igmplen);
356 
357 	return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, skb->dev,
358 		       dst_output);
359 }
360 
361 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
362 {
363 	return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc,type,gdel,sdel);
364 }
365 
366 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
367 	int type, struct igmpv3_grec **ppgr)
368 {
369 	struct net_device *dev = pmc->interface->dev;
370 	struct igmpv3_report *pih;
371 	struct igmpv3_grec *pgr;
372 
373 	if (!skb)
374 		skb = igmpv3_newpack(dev, dev->mtu);
375 	if (!skb)
376 		return NULL;
377 	pgr = (struct igmpv3_grec *)skb_put(skb, sizeof(struct igmpv3_grec));
378 	pgr->grec_type = type;
379 	pgr->grec_auxwords = 0;
380 	pgr->grec_nsrcs = 0;
381 	pgr->grec_mca = pmc->multiaddr;
382 	pih = (struct igmpv3_report *)skb->h.igmph;
383 	pih->ngrec = htons(ntohs(pih->ngrec)+1);
384 	*ppgr = pgr;
385 	return skb;
386 }
387 
388 #define AVAILABLE(skb) ((skb) ? ((skb)->dev ? (skb)->dev->mtu - (skb)->len : \
389 	skb_tailroom(skb)) : 0)
390 
391 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
392 	int type, int gdeleted, int sdeleted)
393 {
394 	struct net_device *dev = pmc->interface->dev;
395 	struct igmpv3_report *pih;
396 	struct igmpv3_grec *pgr = NULL;
397 	struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
398 	int scount, stotal, first, isquery, truncate;
399 
400 	if (pmc->multiaddr == IGMP_ALL_HOSTS)
401 		return skb;
402 
403 	isquery = type == IGMPV3_MODE_IS_INCLUDE ||
404 		  type == IGMPV3_MODE_IS_EXCLUDE;
405 	truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
406 		    type == IGMPV3_CHANGE_TO_EXCLUDE;
407 
408 	stotal = scount = 0;
409 
410 	psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
411 
412 	if (!*psf_list)
413 		goto empty_source;
414 
415 	pih = skb ? (struct igmpv3_report *)skb->h.igmph : NULL;
416 
417 	/* EX and TO_EX get a fresh packet, if needed */
418 	if (truncate) {
419 		if (pih && pih->ngrec &&
420 		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
421 			if (skb)
422 				igmpv3_sendpack(skb);
423 			skb = igmpv3_newpack(dev, dev->mtu);
424 		}
425 	}
426 	first = 1;
427 	psf_prev = NULL;
428 	for (psf=*psf_list; psf; psf=psf_next) {
429 		__be32 *psrc;
430 
431 		psf_next = psf->sf_next;
432 
433 		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
434 			psf_prev = psf;
435 			continue;
436 		}
437 
438 		/* clear marks on query responses */
439 		if (isquery)
440 			psf->sf_gsresp = 0;
441 
442 		if (AVAILABLE(skb) < sizeof(__be32) +
443 		    first*sizeof(struct igmpv3_grec)) {
444 			if (truncate && !first)
445 				break;	 /* truncate these */
446 			if (pgr)
447 				pgr->grec_nsrcs = htons(scount);
448 			if (skb)
449 				igmpv3_sendpack(skb);
450 			skb = igmpv3_newpack(dev, dev->mtu);
451 			first = 1;
452 			scount = 0;
453 		}
454 		if (first) {
455 			skb = add_grhead(skb, pmc, type, &pgr);
456 			first = 0;
457 		}
458 		if (!skb)
459 			return NULL;
460 		psrc = (__be32 *)skb_put(skb, sizeof(__be32));
461 		*psrc = psf->sf_inaddr;
462 		scount++; stotal++;
463 		if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
464 		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
465 			psf->sf_crcount--;
466 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
467 				if (psf_prev)
468 					psf_prev->sf_next = psf->sf_next;
469 				else
470 					*psf_list = psf->sf_next;
471 				kfree(psf);
472 				continue;
473 			}
474 		}
475 		psf_prev = psf;
476 	}
477 
478 empty_source:
479 	if (!stotal) {
480 		if (type == IGMPV3_ALLOW_NEW_SOURCES ||
481 		    type == IGMPV3_BLOCK_OLD_SOURCES)
482 			return skb;
483 		if (pmc->crcount || isquery) {
484 			/* make sure we have room for group header */
485 			if (skb && AVAILABLE(skb)<sizeof(struct igmpv3_grec)) {
486 				igmpv3_sendpack(skb);
487 				skb = NULL; /* add_grhead will get a new one */
488 			}
489 			skb = add_grhead(skb, pmc, type, &pgr);
490 		}
491 	}
492 	if (pgr)
493 		pgr->grec_nsrcs = htons(scount);
494 
495 	if (isquery)
496 		pmc->gsquery = 0;	/* clear query state on report */
497 	return skb;
498 }
499 
500 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
501 {
502 	struct sk_buff *skb = NULL;
503 	int type;
504 
505 	if (!pmc) {
506 		read_lock(&in_dev->mc_list_lock);
507 		for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
508 			if (pmc->multiaddr == IGMP_ALL_HOSTS)
509 				continue;
510 			spin_lock_bh(&pmc->lock);
511 			if (pmc->sfcount[MCAST_EXCLUDE])
512 				type = IGMPV3_MODE_IS_EXCLUDE;
513 			else
514 				type = IGMPV3_MODE_IS_INCLUDE;
515 			skb = add_grec(skb, pmc, type, 0, 0);
516 			spin_unlock_bh(&pmc->lock);
517 		}
518 		read_unlock(&in_dev->mc_list_lock);
519 	} else {
520 		spin_lock_bh(&pmc->lock);
521 		if (pmc->sfcount[MCAST_EXCLUDE])
522 			type = IGMPV3_MODE_IS_EXCLUDE;
523 		else
524 			type = IGMPV3_MODE_IS_INCLUDE;
525 		skb = add_grec(skb, pmc, type, 0, 0);
526 		spin_unlock_bh(&pmc->lock);
527 	}
528 	if (!skb)
529 		return 0;
530 	return igmpv3_sendpack(skb);
531 }
532 
533 /*
534  * remove zero-count source records from a source filter list
535  */
536 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
537 {
538 	struct ip_sf_list *psf_prev, *psf_next, *psf;
539 
540 	psf_prev = NULL;
541 	for (psf=*ppsf; psf; psf = psf_next) {
542 		psf_next = psf->sf_next;
543 		if (psf->sf_crcount == 0) {
544 			if (psf_prev)
545 				psf_prev->sf_next = psf->sf_next;
546 			else
547 				*ppsf = psf->sf_next;
548 			kfree(psf);
549 		} else
550 			psf_prev = psf;
551 	}
552 }
553 
554 static void igmpv3_send_cr(struct in_device *in_dev)
555 {
556 	struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
557 	struct sk_buff *skb = NULL;
558 	int type, dtype;
559 
560 	read_lock(&in_dev->mc_list_lock);
561 	spin_lock_bh(&in_dev->mc_tomb_lock);
562 
563 	/* deleted MCA's */
564 	pmc_prev = NULL;
565 	for (pmc=in_dev->mc_tomb; pmc; pmc=pmc_next) {
566 		pmc_next = pmc->next;
567 		if (pmc->sfmode == MCAST_INCLUDE) {
568 			type = IGMPV3_BLOCK_OLD_SOURCES;
569 			dtype = IGMPV3_BLOCK_OLD_SOURCES;
570 			skb = add_grec(skb, pmc, type, 1, 0);
571 			skb = add_grec(skb, pmc, dtype, 1, 1);
572 		}
573 		if (pmc->crcount) {
574 			if (pmc->sfmode == MCAST_EXCLUDE) {
575 				type = IGMPV3_CHANGE_TO_INCLUDE;
576 				skb = add_grec(skb, pmc, type, 1, 0);
577 			}
578 			pmc->crcount--;
579 			if (pmc->crcount == 0) {
580 				igmpv3_clear_zeros(&pmc->tomb);
581 				igmpv3_clear_zeros(&pmc->sources);
582 			}
583 		}
584 		if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
585 			if (pmc_prev)
586 				pmc_prev->next = pmc_next;
587 			else
588 				in_dev->mc_tomb = pmc_next;
589 			in_dev_put(pmc->interface);
590 			kfree(pmc);
591 		} else
592 			pmc_prev = pmc;
593 	}
594 	spin_unlock_bh(&in_dev->mc_tomb_lock);
595 
596 	/* change recs */
597 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
598 		spin_lock_bh(&pmc->lock);
599 		if (pmc->sfcount[MCAST_EXCLUDE]) {
600 			type = IGMPV3_BLOCK_OLD_SOURCES;
601 			dtype = IGMPV3_ALLOW_NEW_SOURCES;
602 		} else {
603 			type = IGMPV3_ALLOW_NEW_SOURCES;
604 			dtype = IGMPV3_BLOCK_OLD_SOURCES;
605 		}
606 		skb = add_grec(skb, pmc, type, 0, 0);
607 		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
608 
609 		/* filter mode changes */
610 		if (pmc->crcount) {
611 			if (pmc->sfmode == MCAST_EXCLUDE)
612 				type = IGMPV3_CHANGE_TO_EXCLUDE;
613 			else
614 				type = IGMPV3_CHANGE_TO_INCLUDE;
615 			skb = add_grec(skb, pmc, type, 0, 0);
616 			pmc->crcount--;
617 		}
618 		spin_unlock_bh(&pmc->lock);
619 	}
620 	read_unlock(&in_dev->mc_list_lock);
621 
622 	if (!skb)
623 		return;
624 	(void) igmpv3_sendpack(skb);
625 }
626 
627 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
628 	int type)
629 {
630 	struct sk_buff *skb;
631 	struct iphdr *iph;
632 	struct igmphdr *ih;
633 	struct rtable *rt;
634 	struct net_device *dev = in_dev->dev;
635 	__be32	group = pmc ? pmc->multiaddr : 0;
636 	__be32	dst;
637 
638 	if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
639 		return igmpv3_send_report(in_dev, pmc);
640 	else if (type == IGMP_HOST_LEAVE_MESSAGE)
641 		dst = IGMP_ALL_ROUTER;
642 	else
643 		dst = group;
644 
645 	{
646 		struct flowi fl = { .oif = dev->ifindex,
647 				    .nl_u = { .ip4_u = { .daddr = dst } },
648 				    .proto = IPPROTO_IGMP };
649 		if (ip_route_output_key(&rt, &fl))
650 			return -1;
651 	}
652 	if (rt->rt_src == 0) {
653 		ip_rt_put(rt);
654 		return -1;
655 	}
656 
657 	skb=alloc_skb(IGMP_SIZE+LL_RESERVED_SPACE(dev), GFP_ATOMIC);
658 	if (skb == NULL) {
659 		ip_rt_put(rt);
660 		return -1;
661 	}
662 
663 	skb->dst = &rt->u.dst;
664 
665 	skb_reserve(skb, LL_RESERVED_SPACE(dev));
666 
667 	skb->nh.iph = iph = (struct iphdr *)skb_put(skb, sizeof(struct iphdr)+4);
668 
669 	iph->version  = 4;
670 	iph->ihl      = (sizeof(struct iphdr)+4)>>2;
671 	iph->tos      = 0xc0;
672 	iph->frag_off = htons(IP_DF);
673 	iph->ttl      = 1;
674 	iph->daddr    = dst;
675 	iph->saddr    = rt->rt_src;
676 	iph->protocol = IPPROTO_IGMP;
677 	iph->tot_len  = htons(IGMP_SIZE);
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 	ip_send_check(iph);
684 
685 	ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
686 	ih->type=type;
687 	ih->code=0;
688 	ih->csum=0;
689 	ih->group=group;
690 	ih->csum=ip_compute_csum((void *)ih, sizeof(struct igmphdr));
691 
692 	return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, rt->u.dst.dev,
693 		       dst_output);
694 }
695 
696 static void igmp_gq_timer_expire(unsigned long data)
697 {
698 	struct in_device *in_dev = (struct in_device *)data;
699 
700 	in_dev->mr_gq_running = 0;
701 	igmpv3_send_report(in_dev, NULL);
702 	__in_dev_put(in_dev);
703 }
704 
705 static void igmp_ifc_timer_expire(unsigned long data)
706 {
707 	struct in_device *in_dev = (struct in_device *)data;
708 
709 	igmpv3_send_cr(in_dev);
710 	if (in_dev->mr_ifc_count) {
711 		in_dev->mr_ifc_count--;
712 		igmp_ifc_start_timer(in_dev, IGMP_Unsolicited_Report_Interval);
713 	}
714 	__in_dev_put(in_dev);
715 }
716 
717 static void igmp_ifc_event(struct in_device *in_dev)
718 {
719 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
720 		return;
721 	in_dev->mr_ifc_count = in_dev->mr_qrv ? in_dev->mr_qrv :
722 		IGMP_Unsolicited_Report_Count;
723 	igmp_ifc_start_timer(in_dev, 1);
724 }
725 
726 
727 static void igmp_timer_expire(unsigned long data)
728 {
729 	struct ip_mc_list *im=(struct ip_mc_list *)data;
730 	struct in_device *in_dev = im->interface;
731 
732 	spin_lock(&im->lock);
733 	im->tm_running=0;
734 
735 	if (im->unsolicit_count) {
736 		im->unsolicit_count--;
737 		igmp_start_timer(im, IGMP_Unsolicited_Report_Interval);
738 	}
739 	im->reporter = 1;
740 	spin_unlock(&im->lock);
741 
742 	if (IGMP_V1_SEEN(in_dev))
743 		igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
744 	else if (IGMP_V2_SEEN(in_dev))
745 		igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
746 	else
747 		igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
748 
749 	ip_ma_put(im);
750 }
751 
752 /* mark EXCLUDE-mode sources */
753 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
754 {
755 	struct ip_sf_list *psf;
756 	int i, scount;
757 
758 	scount = 0;
759 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
760 		if (scount == nsrcs)
761 			break;
762 		for (i=0; i<nsrcs; i++) {
763 			/* skip inactive filters */
764 			if (pmc->sfcount[MCAST_INCLUDE] ||
765 			    pmc->sfcount[MCAST_EXCLUDE] !=
766 			    psf->sf_count[MCAST_EXCLUDE])
767 				continue;
768 			if (srcs[i] == psf->sf_inaddr) {
769 				scount++;
770 				break;
771 			}
772 		}
773 	}
774 	pmc->gsquery = 0;
775 	if (scount == nsrcs)	/* all sources excluded */
776 		return 0;
777 	return 1;
778 }
779 
780 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
781 {
782 	struct ip_sf_list *psf;
783 	int i, scount;
784 
785 	if (pmc->sfmode == MCAST_EXCLUDE)
786 		return igmp_xmarksources(pmc, nsrcs, srcs);
787 
788 	/* mark INCLUDE-mode sources */
789 	scount = 0;
790 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
791 		if (scount == nsrcs)
792 			break;
793 		for (i=0; i<nsrcs; i++)
794 			if (srcs[i] == psf->sf_inaddr) {
795 				psf->sf_gsresp = 1;
796 				scount++;
797 				break;
798 			}
799 	}
800 	if (!scount) {
801 		pmc->gsquery = 0;
802 		return 0;
803 	}
804 	pmc->gsquery = 1;
805 	return 1;
806 }
807 
808 static void igmp_heard_report(struct in_device *in_dev, __be32 group)
809 {
810 	struct ip_mc_list *im;
811 
812 	/* Timers are only set for non-local groups */
813 
814 	if (group == IGMP_ALL_HOSTS)
815 		return;
816 
817 	read_lock(&in_dev->mc_list_lock);
818 	for (im=in_dev->mc_list; im!=NULL; im=im->next) {
819 		if (im->multiaddr == group) {
820 			igmp_stop_timer(im);
821 			break;
822 		}
823 	}
824 	read_unlock(&in_dev->mc_list_lock);
825 }
826 
827 static void igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
828 	int len)
829 {
830 	struct igmphdr 		*ih = skb->h.igmph;
831 	struct igmpv3_query *ih3 = (struct igmpv3_query *)ih;
832 	struct ip_mc_list	*im;
833 	__be32			group = ih->group;
834 	int			max_delay;
835 	int			mark = 0;
836 
837 
838 	if (len == 8) {
839 		if (ih->code == 0) {
840 			/* Alas, old v1 router presents here. */
841 
842 			max_delay = IGMP_Query_Response_Interval;
843 			in_dev->mr_v1_seen = jiffies +
844 				IGMP_V1_Router_Present_Timeout;
845 			group = 0;
846 		} else {
847 			/* v2 router present */
848 			max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
849 			in_dev->mr_v2_seen = jiffies +
850 				IGMP_V2_Router_Present_Timeout;
851 		}
852 		/* cancel the interface change timer */
853 		in_dev->mr_ifc_count = 0;
854 		if (del_timer(&in_dev->mr_ifc_timer))
855 			__in_dev_put(in_dev);
856 		/* clear deleted report items */
857 		igmpv3_clear_delrec(in_dev);
858 	} else if (len < 12) {
859 		return;	/* ignore bogus packet; freed by caller */
860 	} else { /* v3 */
861 		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
862 			return;
863 
864 		ih3 = (struct igmpv3_query *) skb->h.raw;
865 		if (ih3->nsrcs) {
866 			if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
867 					   + ntohs(ih3->nsrcs)*sizeof(__be32)))
868 				return;
869 			ih3 = (struct igmpv3_query *) skb->h.raw;
870 		}
871 
872 		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
873 		if (!max_delay)
874 			max_delay = 1;	/* can't mod w/ 0 */
875 		in_dev->mr_maxdelay = max_delay;
876 		if (ih3->qrv)
877 			in_dev->mr_qrv = ih3->qrv;
878 		if (!group) { /* general query */
879 			if (ih3->nsrcs)
880 				return;	/* no sources allowed */
881 			igmp_gq_start_timer(in_dev);
882 			return;
883 		}
884 		/* mark sources to include, if group & source-specific */
885 		mark = ih3->nsrcs != 0;
886 	}
887 
888 	/*
889 	 * - Start the timers in all of our membership records
890 	 *   that the query applies to for the interface on
891 	 *   which the query arrived excl. those that belong
892 	 *   to a "local" group (224.0.0.X)
893 	 * - For timers already running check if they need to
894 	 *   be reset.
895 	 * - Use the igmp->igmp_code field as the maximum
896 	 *   delay possible
897 	 */
898 	read_lock(&in_dev->mc_list_lock);
899 	for (im=in_dev->mc_list; im!=NULL; im=im->next) {
900 		int changed;
901 
902 		if (group && group != im->multiaddr)
903 			continue;
904 		if (im->multiaddr == IGMP_ALL_HOSTS)
905 			continue;
906 		spin_lock_bh(&im->lock);
907 		if (im->tm_running)
908 			im->gsquery = im->gsquery && mark;
909 		else
910 			im->gsquery = mark;
911 		changed = !im->gsquery ||
912 			igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
913 		spin_unlock_bh(&im->lock);
914 		if (changed)
915 			igmp_mod_timer(im, max_delay);
916 	}
917 	read_unlock(&in_dev->mc_list_lock);
918 }
919 
920 int igmp_rcv(struct sk_buff *skb)
921 {
922 	/* This basically follows the spec line by line -- see RFC1112 */
923 	struct igmphdr *ih;
924 	struct in_device *in_dev = in_dev_get(skb->dev);
925 	int len = skb->len;
926 
927 	if (in_dev==NULL) {
928 		kfree_skb(skb);
929 		return 0;
930 	}
931 
932 	if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
933 		goto drop;
934 
935 	switch (skb->ip_summed) {
936 	case CHECKSUM_COMPLETE:
937 		if (!csum_fold(skb->csum))
938 			break;
939 		/* fall through */
940 	case CHECKSUM_NONE:
941 		skb->csum = 0;
942 		if (__skb_checksum_complete(skb))
943 			goto drop;
944 	}
945 
946 	ih = skb->h.igmph;
947 	switch (ih->type) {
948 	case IGMP_HOST_MEMBERSHIP_QUERY:
949 		igmp_heard_query(in_dev, skb, len);
950 		break;
951 	case IGMP_HOST_MEMBERSHIP_REPORT:
952 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
953 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
954 		/* Is it our report looped back? */
955 		if (((struct rtable*)skb->dst)->fl.iif == 0)
956 			break;
957 		/* don't rely on MC router hearing unicast reports */
958 		if (skb->pkt_type == PACKET_MULTICAST ||
959 		    skb->pkt_type == PACKET_BROADCAST)
960 			igmp_heard_report(in_dev, ih->group);
961 		break;
962 	case IGMP_PIM:
963 #ifdef CONFIG_IP_PIMSM_V1
964 		in_dev_put(in_dev);
965 		return pim_rcv_v1(skb);
966 #endif
967 	case IGMP_DVMRP:
968 	case IGMP_TRACE:
969 	case IGMP_HOST_LEAVE_MESSAGE:
970 	case IGMP_MTRACE:
971 	case IGMP_MTRACE_RESP:
972 		break;
973 	default:
974 		break;
975 	}
976 
977 drop:
978 	in_dev_put(in_dev);
979 	kfree_skb(skb);
980 	return 0;
981 }
982 
983 #endif
984 
985 
986 /*
987  *	Add a filter to a device
988  */
989 
990 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
991 {
992 	char buf[MAX_ADDR_LEN];
993 	struct net_device *dev = in_dev->dev;
994 
995 	/* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
996 	   We will get multicast token leakage, when IFF_MULTICAST
997 	   is changed. This check should be done in dev->set_multicast_list
998 	   routine. Something sort of:
999 	   if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1000 	   --ANK
1001 	   */
1002 	if (arp_mc_map(addr, buf, dev, 0) == 0)
1003 		dev_mc_add(dev,buf,dev->addr_len,0);
1004 }
1005 
1006 /*
1007  *	Remove a filter from a device
1008  */
1009 
1010 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1011 {
1012 	char buf[MAX_ADDR_LEN];
1013 	struct net_device *dev = in_dev->dev;
1014 
1015 	if (arp_mc_map(addr, buf, dev, 0) == 0)
1016 		dev_mc_delete(dev,buf,dev->addr_len,0);
1017 }
1018 
1019 #ifdef CONFIG_IP_MULTICAST
1020 /*
1021  * deleted ip_mc_list manipulation
1022  */
1023 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1024 {
1025 	struct ip_mc_list *pmc;
1026 
1027 	/* this is an "ip_mc_list" for convenience; only the fields below
1028 	 * are actually used. In particular, the refcnt and users are not
1029 	 * used for management of the delete list. Using the same structure
1030 	 * for deleted items allows change reports to use common code with
1031 	 * non-deleted or query-response MCA's.
1032 	 */
1033 	pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
1034 	if (!pmc)
1035 		return;
1036 	spin_lock_bh(&im->lock);
1037 	pmc->interface = im->interface;
1038 	in_dev_hold(in_dev);
1039 	pmc->multiaddr = im->multiaddr;
1040 	pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1041 		IGMP_Unsolicited_Report_Count;
1042 	pmc->sfmode = im->sfmode;
1043 	if (pmc->sfmode == MCAST_INCLUDE) {
1044 		struct ip_sf_list *psf;
1045 
1046 		pmc->tomb = im->tomb;
1047 		pmc->sources = im->sources;
1048 		im->tomb = im->sources = NULL;
1049 		for (psf=pmc->sources; psf; psf=psf->sf_next)
1050 			psf->sf_crcount = pmc->crcount;
1051 	}
1052 	spin_unlock_bh(&im->lock);
1053 
1054 	spin_lock_bh(&in_dev->mc_tomb_lock);
1055 	pmc->next = in_dev->mc_tomb;
1056 	in_dev->mc_tomb = pmc;
1057 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1058 }
1059 
1060 static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr)
1061 {
1062 	struct ip_mc_list *pmc, *pmc_prev;
1063 	struct ip_sf_list *psf, *psf_next;
1064 
1065 	spin_lock_bh(&in_dev->mc_tomb_lock);
1066 	pmc_prev = NULL;
1067 	for (pmc=in_dev->mc_tomb; pmc; pmc=pmc->next) {
1068 		if (pmc->multiaddr == multiaddr)
1069 			break;
1070 		pmc_prev = pmc;
1071 	}
1072 	if (pmc) {
1073 		if (pmc_prev)
1074 			pmc_prev->next = pmc->next;
1075 		else
1076 			in_dev->mc_tomb = pmc->next;
1077 	}
1078 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1079 	if (pmc) {
1080 		for (psf=pmc->tomb; psf; psf=psf_next) {
1081 			psf_next = psf->sf_next;
1082 			kfree(psf);
1083 		}
1084 		in_dev_put(pmc->interface);
1085 		kfree(pmc);
1086 	}
1087 }
1088 
1089 static void igmpv3_clear_delrec(struct in_device *in_dev)
1090 {
1091 	struct ip_mc_list *pmc, *nextpmc;
1092 
1093 	spin_lock_bh(&in_dev->mc_tomb_lock);
1094 	pmc = in_dev->mc_tomb;
1095 	in_dev->mc_tomb = NULL;
1096 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1097 
1098 	for (; pmc; pmc = nextpmc) {
1099 		nextpmc = pmc->next;
1100 		ip_mc_clear_src(pmc);
1101 		in_dev_put(pmc->interface);
1102 		kfree(pmc);
1103 	}
1104 	/* clear dead sources, too */
1105 	read_lock(&in_dev->mc_list_lock);
1106 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1107 		struct ip_sf_list *psf, *psf_next;
1108 
1109 		spin_lock_bh(&pmc->lock);
1110 		psf = pmc->tomb;
1111 		pmc->tomb = NULL;
1112 		spin_unlock_bh(&pmc->lock);
1113 		for (; psf; psf=psf_next) {
1114 			psf_next = psf->sf_next;
1115 			kfree(psf);
1116 		}
1117 	}
1118 	read_unlock(&in_dev->mc_list_lock);
1119 }
1120 #endif
1121 
1122 static void igmp_group_dropped(struct ip_mc_list *im)
1123 {
1124 	struct in_device *in_dev = im->interface;
1125 #ifdef CONFIG_IP_MULTICAST
1126 	int reporter;
1127 #endif
1128 
1129 	if (im->loaded) {
1130 		im->loaded = 0;
1131 		ip_mc_filter_del(in_dev, im->multiaddr);
1132 	}
1133 
1134 #ifdef CONFIG_IP_MULTICAST
1135 	if (im->multiaddr == IGMP_ALL_HOSTS)
1136 		return;
1137 
1138 	reporter = im->reporter;
1139 	igmp_stop_timer(im);
1140 
1141 	if (!in_dev->dead) {
1142 		if (IGMP_V1_SEEN(in_dev))
1143 			goto done;
1144 		if (IGMP_V2_SEEN(in_dev)) {
1145 			if (reporter)
1146 				igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1147 			goto done;
1148 		}
1149 		/* IGMPv3 */
1150 		igmpv3_add_delrec(in_dev, im);
1151 
1152 		igmp_ifc_event(in_dev);
1153 	}
1154 done:
1155 #endif
1156 	ip_mc_clear_src(im);
1157 }
1158 
1159 static void igmp_group_added(struct ip_mc_list *im)
1160 {
1161 	struct in_device *in_dev = im->interface;
1162 
1163 	if (im->loaded == 0) {
1164 		im->loaded = 1;
1165 		ip_mc_filter_add(in_dev, im->multiaddr);
1166 	}
1167 
1168 #ifdef CONFIG_IP_MULTICAST
1169 	if (im->multiaddr == IGMP_ALL_HOSTS)
1170 		return;
1171 
1172 	if (in_dev->dead)
1173 		return;
1174 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1175 		spin_lock_bh(&im->lock);
1176 		igmp_start_timer(im, IGMP_Initial_Report_Delay);
1177 		spin_unlock_bh(&im->lock);
1178 		return;
1179 	}
1180 	/* else, v3 */
1181 
1182 	im->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1183 		IGMP_Unsolicited_Report_Count;
1184 	igmp_ifc_event(in_dev);
1185 #endif
1186 }
1187 
1188 
1189 /*
1190  *	Multicast list managers
1191  */
1192 
1193 
1194 /*
1195  *	A socket has joined a multicast group on device dev.
1196  */
1197 
1198 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1199 {
1200 	struct ip_mc_list *im;
1201 
1202 	ASSERT_RTNL();
1203 
1204 	for (im=in_dev->mc_list; im; im=im->next) {
1205 		if (im->multiaddr == addr) {
1206 			im->users++;
1207 			ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1208 			goto out;
1209 		}
1210 	}
1211 
1212 	im = kmalloc(sizeof(*im), GFP_KERNEL);
1213 	if (!im)
1214 		goto out;
1215 
1216 	im->users=1;
1217 	im->interface=in_dev;
1218 	in_dev_hold(in_dev);
1219 	im->multiaddr=addr;
1220 	/* initial mode is (EX, empty) */
1221 	im->sfmode = MCAST_EXCLUDE;
1222 	im->sfcount[MCAST_INCLUDE] = 0;
1223 	im->sfcount[MCAST_EXCLUDE] = 1;
1224 	im->sources = NULL;
1225 	im->tomb = NULL;
1226 	im->crcount = 0;
1227 	atomic_set(&im->refcnt, 1);
1228 	spin_lock_init(&im->lock);
1229 #ifdef CONFIG_IP_MULTICAST
1230 	im->tm_running=0;
1231 	init_timer(&im->timer);
1232 	im->timer.data=(unsigned long)im;
1233 	im->timer.function=&igmp_timer_expire;
1234 	im->unsolicit_count = IGMP_Unsolicited_Report_Count;
1235 	im->reporter = 0;
1236 	im->gsquery = 0;
1237 #endif
1238 	im->loaded = 0;
1239 	write_lock_bh(&in_dev->mc_list_lock);
1240 	im->next=in_dev->mc_list;
1241 	in_dev->mc_list=im;
1242 	write_unlock_bh(&in_dev->mc_list_lock);
1243 #ifdef CONFIG_IP_MULTICAST
1244 	igmpv3_del_delrec(in_dev, im->multiaddr);
1245 #endif
1246 	igmp_group_added(im);
1247 	if (!in_dev->dead)
1248 		ip_rt_multicast_event(in_dev);
1249 out:
1250 	return;
1251 }
1252 
1253 /*
1254  *	Resend IGMP JOIN report; used for bonding.
1255  */
1256 void ip_mc_rejoin_group(struct ip_mc_list *im)
1257 {
1258 #ifdef CONFIG_IP_MULTICAST
1259 	struct in_device *in_dev = im->interface;
1260 
1261 	if (im->multiaddr == IGMP_ALL_HOSTS)
1262 		return;
1263 
1264 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1265 		igmp_mod_timer(im, IGMP_Initial_Report_Delay);
1266 		return;
1267 	}
1268 	/* else, v3 */
1269 	im->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1270 		IGMP_Unsolicited_Report_Count;
1271 	igmp_ifc_event(in_dev);
1272 #endif
1273 }
1274 
1275 /*
1276  *	A socket has left a multicast group on device dev
1277  */
1278 
1279 void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
1280 {
1281 	struct ip_mc_list *i, **ip;
1282 
1283 	ASSERT_RTNL();
1284 
1285 	for (ip=&in_dev->mc_list; (i=*ip)!=NULL; ip=&i->next) {
1286 		if (i->multiaddr==addr) {
1287 			if (--i->users == 0) {
1288 				write_lock_bh(&in_dev->mc_list_lock);
1289 				*ip = i->next;
1290 				write_unlock_bh(&in_dev->mc_list_lock);
1291 				igmp_group_dropped(i);
1292 
1293 				if (!in_dev->dead)
1294 					ip_rt_multicast_event(in_dev);
1295 
1296 				ip_ma_put(i);
1297 				return;
1298 			}
1299 			break;
1300 		}
1301 	}
1302 }
1303 
1304 /* Device going down */
1305 
1306 void ip_mc_down(struct in_device *in_dev)
1307 {
1308 	struct ip_mc_list *i;
1309 
1310 	ASSERT_RTNL();
1311 
1312 	for (i=in_dev->mc_list; i; i=i->next)
1313 		igmp_group_dropped(i);
1314 
1315 #ifdef CONFIG_IP_MULTICAST
1316 	in_dev->mr_ifc_count = 0;
1317 	if (del_timer(&in_dev->mr_ifc_timer))
1318 		__in_dev_put(in_dev);
1319 	in_dev->mr_gq_running = 0;
1320 	if (del_timer(&in_dev->mr_gq_timer))
1321 		__in_dev_put(in_dev);
1322 	igmpv3_clear_delrec(in_dev);
1323 #endif
1324 
1325 	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1326 }
1327 
1328 void ip_mc_init_dev(struct in_device *in_dev)
1329 {
1330 	ASSERT_RTNL();
1331 
1332 	in_dev->mc_tomb = NULL;
1333 #ifdef CONFIG_IP_MULTICAST
1334 	in_dev->mr_gq_running = 0;
1335 	init_timer(&in_dev->mr_gq_timer);
1336 	in_dev->mr_gq_timer.data=(unsigned long) in_dev;
1337 	in_dev->mr_gq_timer.function=&igmp_gq_timer_expire;
1338 	in_dev->mr_ifc_count = 0;
1339 	init_timer(&in_dev->mr_ifc_timer);
1340 	in_dev->mr_ifc_timer.data=(unsigned long) in_dev;
1341 	in_dev->mr_ifc_timer.function=&igmp_ifc_timer_expire;
1342 	in_dev->mr_qrv = IGMP_Unsolicited_Report_Count;
1343 #endif
1344 
1345 	rwlock_init(&in_dev->mc_list_lock);
1346 	spin_lock_init(&in_dev->mc_tomb_lock);
1347 }
1348 
1349 /* Device going up */
1350 
1351 void ip_mc_up(struct in_device *in_dev)
1352 {
1353 	struct ip_mc_list *i;
1354 
1355 	ASSERT_RTNL();
1356 
1357 	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1358 
1359 	for (i=in_dev->mc_list; i; i=i->next)
1360 		igmp_group_added(i);
1361 }
1362 
1363 /*
1364  *	Device is about to be destroyed: clean up.
1365  */
1366 
1367 void ip_mc_destroy_dev(struct in_device *in_dev)
1368 {
1369 	struct ip_mc_list *i;
1370 
1371 	ASSERT_RTNL();
1372 
1373 	/* Deactivate timers */
1374 	ip_mc_down(in_dev);
1375 
1376 	write_lock_bh(&in_dev->mc_list_lock);
1377 	while ((i = in_dev->mc_list) != NULL) {
1378 		in_dev->mc_list = i->next;
1379 		write_unlock_bh(&in_dev->mc_list_lock);
1380 
1381 		igmp_group_dropped(i);
1382 		ip_ma_put(i);
1383 
1384 		write_lock_bh(&in_dev->mc_list_lock);
1385 	}
1386 	write_unlock_bh(&in_dev->mc_list_lock);
1387 }
1388 
1389 static struct in_device * ip_mc_find_dev(struct ip_mreqn *imr)
1390 {
1391 	struct flowi fl = { .nl_u = { .ip4_u =
1392 				      { .daddr = imr->imr_multiaddr.s_addr } } };
1393 	struct rtable *rt;
1394 	struct net_device *dev = NULL;
1395 	struct in_device *idev = NULL;
1396 
1397 	if (imr->imr_ifindex) {
1398 		idev = inetdev_by_index(imr->imr_ifindex);
1399 		if (idev)
1400 			__in_dev_put(idev);
1401 		return idev;
1402 	}
1403 	if (imr->imr_address.s_addr) {
1404 		dev = ip_dev_find(imr->imr_address.s_addr);
1405 		if (!dev)
1406 			return NULL;
1407 		dev_put(dev);
1408 	}
1409 
1410 	if (!dev && !ip_route_output_key(&rt, &fl)) {
1411 		dev = rt->u.dst.dev;
1412 		ip_rt_put(rt);
1413 	}
1414 	if (dev) {
1415 		imr->imr_ifindex = dev->ifindex;
1416 		idev = __in_dev_get_rtnl(dev);
1417 	}
1418 	return idev;
1419 }
1420 
1421 /*
1422  *	Join a socket to a group
1423  */
1424 int sysctl_igmp_max_memberships __read_mostly = IP_MAX_MEMBERSHIPS;
1425 int sysctl_igmp_max_msf __read_mostly = IP_MAX_MSF;
1426 
1427 
1428 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1429 	__be32 *psfsrc)
1430 {
1431 	struct ip_sf_list *psf, *psf_prev;
1432 	int rv = 0;
1433 
1434 	psf_prev = NULL;
1435 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1436 		if (psf->sf_inaddr == *psfsrc)
1437 			break;
1438 		psf_prev = psf;
1439 	}
1440 	if (!psf || psf->sf_count[sfmode] == 0) {
1441 		/* source filter not found, or count wrong =>  bug */
1442 		return -ESRCH;
1443 	}
1444 	psf->sf_count[sfmode]--;
1445 	if (psf->sf_count[sfmode] == 0) {
1446 		ip_rt_multicast_event(pmc->interface);
1447 	}
1448 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1449 #ifdef CONFIG_IP_MULTICAST
1450 		struct in_device *in_dev = pmc->interface;
1451 #endif
1452 
1453 		/* no more filters for this source */
1454 		if (psf_prev)
1455 			psf_prev->sf_next = psf->sf_next;
1456 		else
1457 			pmc->sources = psf->sf_next;
1458 #ifdef CONFIG_IP_MULTICAST
1459 		if (psf->sf_oldin &&
1460 		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1461 			psf->sf_crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1462 				IGMP_Unsolicited_Report_Count;
1463 			psf->sf_next = pmc->tomb;
1464 			pmc->tomb = psf;
1465 			rv = 1;
1466 		} else
1467 #endif
1468 			kfree(psf);
1469 	}
1470 	return rv;
1471 }
1472 
1473 #ifndef CONFIG_IP_MULTICAST
1474 #define igmp_ifc_event(x)	do { } while (0)
1475 #endif
1476 
1477 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1478 			 int sfcount, __be32 *psfsrc, int delta)
1479 {
1480 	struct ip_mc_list *pmc;
1481 	int	changerec = 0;
1482 	int	i, err;
1483 
1484 	if (!in_dev)
1485 		return -ENODEV;
1486 	read_lock(&in_dev->mc_list_lock);
1487 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1488 		if (*pmca == pmc->multiaddr)
1489 			break;
1490 	}
1491 	if (!pmc) {
1492 		/* MCA not found?? bug */
1493 		read_unlock(&in_dev->mc_list_lock);
1494 		return -ESRCH;
1495 	}
1496 	spin_lock_bh(&pmc->lock);
1497 	read_unlock(&in_dev->mc_list_lock);
1498 #ifdef CONFIG_IP_MULTICAST
1499 	sf_markstate(pmc);
1500 #endif
1501 	if (!delta) {
1502 		err = -EINVAL;
1503 		if (!pmc->sfcount[sfmode])
1504 			goto out_unlock;
1505 		pmc->sfcount[sfmode]--;
1506 	}
1507 	err = 0;
1508 	for (i=0; i<sfcount; i++) {
1509 		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1510 
1511 		changerec |= rv > 0;
1512 		if (!err && rv < 0)
1513 			err = rv;
1514 	}
1515 	if (pmc->sfmode == MCAST_EXCLUDE &&
1516 	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1517 	    pmc->sfcount[MCAST_INCLUDE]) {
1518 #ifdef CONFIG_IP_MULTICAST
1519 		struct ip_sf_list *psf;
1520 #endif
1521 
1522 		/* filter mode change */
1523 		pmc->sfmode = MCAST_INCLUDE;
1524 #ifdef CONFIG_IP_MULTICAST
1525 		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1526 			IGMP_Unsolicited_Report_Count;
1527 		in_dev->mr_ifc_count = pmc->crcount;
1528 		for (psf=pmc->sources; psf; psf = psf->sf_next)
1529 			psf->sf_crcount = 0;
1530 		igmp_ifc_event(pmc->interface);
1531 	} else if (sf_setstate(pmc) || changerec) {
1532 		igmp_ifc_event(pmc->interface);
1533 #endif
1534 	}
1535 out_unlock:
1536 	spin_unlock_bh(&pmc->lock);
1537 	return err;
1538 }
1539 
1540 /*
1541  * Add multicast single-source filter to the interface list
1542  */
1543 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1544 	__be32 *psfsrc, int delta)
1545 {
1546 	struct ip_sf_list *psf, *psf_prev;
1547 
1548 	psf_prev = NULL;
1549 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1550 		if (psf->sf_inaddr == *psfsrc)
1551 			break;
1552 		psf_prev = psf;
1553 	}
1554 	if (!psf) {
1555 		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1556 		if (!psf)
1557 			return -ENOBUFS;
1558 		psf->sf_inaddr = *psfsrc;
1559 		if (psf_prev) {
1560 			psf_prev->sf_next = psf;
1561 		} else
1562 			pmc->sources = psf;
1563 	}
1564 	psf->sf_count[sfmode]++;
1565 	if (psf->sf_count[sfmode] == 1) {
1566 		ip_rt_multicast_event(pmc->interface);
1567 	}
1568 	return 0;
1569 }
1570 
1571 #ifdef CONFIG_IP_MULTICAST
1572 static void sf_markstate(struct ip_mc_list *pmc)
1573 {
1574 	struct ip_sf_list *psf;
1575 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1576 
1577 	for (psf=pmc->sources; psf; psf=psf->sf_next)
1578 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1579 			psf->sf_oldin = mca_xcount ==
1580 				psf->sf_count[MCAST_EXCLUDE] &&
1581 				!psf->sf_count[MCAST_INCLUDE];
1582 		} else
1583 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1584 }
1585 
1586 static int sf_setstate(struct ip_mc_list *pmc)
1587 {
1588 	struct ip_sf_list *psf, *dpsf;
1589 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1590 	int qrv = pmc->interface->mr_qrv;
1591 	int new_in, rv;
1592 
1593 	rv = 0;
1594 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1595 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1596 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1597 				!psf->sf_count[MCAST_INCLUDE];
1598 		} else
1599 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1600 		if (new_in) {
1601 			if (!psf->sf_oldin) {
1602 				struct ip_sf_list *prev = NULL;
1603 
1604 				for (dpsf=pmc->tomb; dpsf; dpsf=dpsf->sf_next) {
1605 					if (dpsf->sf_inaddr == psf->sf_inaddr)
1606 						break;
1607 					prev = dpsf;
1608 				}
1609 				if (dpsf) {
1610 					if (prev)
1611 						prev->sf_next = dpsf->sf_next;
1612 					else
1613 						pmc->tomb = dpsf->sf_next;
1614 					kfree(dpsf);
1615 				}
1616 				psf->sf_crcount = qrv;
1617 				rv++;
1618 			}
1619 		} else if (psf->sf_oldin) {
1620 
1621 			psf->sf_crcount = 0;
1622 			/*
1623 			 * add or update "delete" records if an active filter
1624 			 * is now inactive
1625 			 */
1626 			for (dpsf=pmc->tomb; dpsf; dpsf=dpsf->sf_next)
1627 				if (dpsf->sf_inaddr == psf->sf_inaddr)
1628 					break;
1629 			if (!dpsf) {
1630 				dpsf = (struct ip_sf_list *)
1631 					kmalloc(sizeof(*dpsf), GFP_ATOMIC);
1632 				if (!dpsf)
1633 					continue;
1634 				*dpsf = *psf;
1635 				/* pmc->lock held by callers */
1636 				dpsf->sf_next = pmc->tomb;
1637 				pmc->tomb = dpsf;
1638 			}
1639 			dpsf->sf_crcount = qrv;
1640 			rv++;
1641 		}
1642 	}
1643 	return rv;
1644 }
1645 #endif
1646 
1647 /*
1648  * Add multicast source filter list to the interface list
1649  */
1650 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1651 			 int sfcount, __be32 *psfsrc, int delta)
1652 {
1653 	struct ip_mc_list *pmc;
1654 	int	isexclude;
1655 	int	i, err;
1656 
1657 	if (!in_dev)
1658 		return -ENODEV;
1659 	read_lock(&in_dev->mc_list_lock);
1660 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1661 		if (*pmca == pmc->multiaddr)
1662 			break;
1663 	}
1664 	if (!pmc) {
1665 		/* MCA not found?? bug */
1666 		read_unlock(&in_dev->mc_list_lock);
1667 		return -ESRCH;
1668 	}
1669 	spin_lock_bh(&pmc->lock);
1670 	read_unlock(&in_dev->mc_list_lock);
1671 
1672 #ifdef CONFIG_IP_MULTICAST
1673 	sf_markstate(pmc);
1674 #endif
1675 	isexclude = pmc->sfmode == MCAST_EXCLUDE;
1676 	if (!delta)
1677 		pmc->sfcount[sfmode]++;
1678 	err = 0;
1679 	for (i=0; i<sfcount; i++) {
1680 		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i], delta);
1681 		if (err)
1682 			break;
1683 	}
1684 	if (err) {
1685 		int j;
1686 
1687 		pmc->sfcount[sfmode]--;
1688 		for (j=0; j<i; j++)
1689 			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1690 	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
1691 #ifdef CONFIG_IP_MULTICAST
1692 		struct in_device *in_dev = pmc->interface;
1693 		struct ip_sf_list *psf;
1694 #endif
1695 
1696 		/* filter mode change */
1697 		if (pmc->sfcount[MCAST_EXCLUDE])
1698 			pmc->sfmode = MCAST_EXCLUDE;
1699 		else if (pmc->sfcount[MCAST_INCLUDE])
1700 			pmc->sfmode = MCAST_INCLUDE;
1701 #ifdef CONFIG_IP_MULTICAST
1702 		/* else no filters; keep old mode for reports */
1703 
1704 		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1705 			IGMP_Unsolicited_Report_Count;
1706 		in_dev->mr_ifc_count = pmc->crcount;
1707 		for (psf=pmc->sources; psf; psf = psf->sf_next)
1708 			psf->sf_crcount = 0;
1709 		igmp_ifc_event(in_dev);
1710 	} else if (sf_setstate(pmc)) {
1711 		igmp_ifc_event(in_dev);
1712 #endif
1713 	}
1714 	spin_unlock_bh(&pmc->lock);
1715 	return err;
1716 }
1717 
1718 static void ip_mc_clear_src(struct ip_mc_list *pmc)
1719 {
1720 	struct ip_sf_list *psf, *nextpsf;
1721 
1722 	for (psf=pmc->tomb; psf; psf=nextpsf) {
1723 		nextpsf = psf->sf_next;
1724 		kfree(psf);
1725 	}
1726 	pmc->tomb = NULL;
1727 	for (psf=pmc->sources; psf; psf=nextpsf) {
1728 		nextpsf = psf->sf_next;
1729 		kfree(psf);
1730 	}
1731 	pmc->sources = NULL;
1732 	pmc->sfmode = MCAST_EXCLUDE;
1733 	pmc->sfcount[MCAST_INCLUDE] = 0;
1734 	pmc->sfcount[MCAST_EXCLUDE] = 1;
1735 }
1736 
1737 
1738 /*
1739  * Join a multicast group
1740  */
1741 int ip_mc_join_group(struct sock *sk , struct ip_mreqn *imr)
1742 {
1743 	int err;
1744 	__be32 addr = imr->imr_multiaddr.s_addr;
1745 	struct ip_mc_socklist *iml=NULL, *i;
1746 	struct in_device *in_dev;
1747 	struct inet_sock *inet = inet_sk(sk);
1748 	int ifindex;
1749 	int count = 0;
1750 
1751 	if (!MULTICAST(addr))
1752 		return -EINVAL;
1753 
1754 	rtnl_lock();
1755 
1756 	in_dev = ip_mc_find_dev(imr);
1757 
1758 	if (!in_dev) {
1759 		iml = NULL;
1760 		err = -ENODEV;
1761 		goto done;
1762 	}
1763 
1764 	err = -EADDRINUSE;
1765 	ifindex = imr->imr_ifindex;
1766 	for (i = inet->mc_list; i; i = i->next) {
1767 		if (i->multi.imr_multiaddr.s_addr == addr &&
1768 		    i->multi.imr_ifindex == ifindex)
1769 			goto done;
1770 		count++;
1771 	}
1772 	err = -ENOBUFS;
1773 	if (count >= sysctl_igmp_max_memberships)
1774 		goto done;
1775 	iml = sock_kmalloc(sk,sizeof(*iml),GFP_KERNEL);
1776 	if (iml == NULL)
1777 		goto done;
1778 
1779 	memcpy(&iml->multi, imr, sizeof(*imr));
1780 	iml->next = inet->mc_list;
1781 	iml->sflist = NULL;
1782 	iml->sfmode = MCAST_EXCLUDE;
1783 	inet->mc_list = iml;
1784 	ip_mc_inc_group(in_dev, addr);
1785 	err = 0;
1786 done:
1787 	rtnl_unlock();
1788 	return err;
1789 }
1790 
1791 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
1792 			   struct in_device *in_dev)
1793 {
1794 	int err;
1795 
1796 	if (iml->sflist == 0) {
1797 		/* any-source empty exclude case */
1798 		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1799 			iml->sfmode, 0, NULL, 0);
1800 	}
1801 	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1802 			iml->sfmode, iml->sflist->sl_count,
1803 			iml->sflist->sl_addr, 0);
1804 	sock_kfree_s(sk, iml->sflist, IP_SFLSIZE(iml->sflist->sl_max));
1805 	iml->sflist = NULL;
1806 	return err;
1807 }
1808 
1809 /*
1810  *	Ask a socket to leave a group.
1811  */
1812 
1813 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
1814 {
1815 	struct inet_sock *inet = inet_sk(sk);
1816 	struct ip_mc_socklist *iml, **imlp;
1817 	struct in_device *in_dev;
1818 	__be32 group = imr->imr_multiaddr.s_addr;
1819 	u32 ifindex;
1820 	int ret = -EADDRNOTAVAIL;
1821 
1822 	rtnl_lock();
1823 	in_dev = ip_mc_find_dev(imr);
1824 	ifindex = imr->imr_ifindex;
1825 	for (imlp = &inet->mc_list; (iml = *imlp) != NULL; imlp = &iml->next) {
1826 		if (iml->multi.imr_multiaddr.s_addr != group)
1827 			continue;
1828 		if (ifindex) {
1829 			if (iml->multi.imr_ifindex != ifindex)
1830 				continue;
1831 		} else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
1832 				iml->multi.imr_address.s_addr)
1833 			continue;
1834 
1835 		(void) ip_mc_leave_src(sk, iml, in_dev);
1836 
1837 		*imlp = iml->next;
1838 
1839 		if (in_dev)
1840 			ip_mc_dec_group(in_dev, group);
1841 		rtnl_unlock();
1842 		sock_kfree_s(sk, iml, sizeof(*iml));
1843 		return 0;
1844 	}
1845 	if (!in_dev)
1846 		ret = -ENODEV;
1847 	rtnl_unlock();
1848 	return ret;
1849 }
1850 
1851 int ip_mc_source(int add, int omode, struct sock *sk, struct
1852 	ip_mreq_source *mreqs, int ifindex)
1853 {
1854 	int err;
1855 	struct ip_mreqn imr;
1856 	__be32 addr = mreqs->imr_multiaddr;
1857 	struct ip_mc_socklist *pmc;
1858 	struct in_device *in_dev = NULL;
1859 	struct inet_sock *inet = inet_sk(sk);
1860 	struct ip_sf_socklist *psl;
1861 	int leavegroup = 0;
1862 	int i, j, rv;
1863 
1864 	if (!MULTICAST(addr))
1865 		return -EINVAL;
1866 
1867 	rtnl_lock();
1868 
1869 	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
1870 	imr.imr_address.s_addr = mreqs->imr_interface;
1871 	imr.imr_ifindex = ifindex;
1872 	in_dev = ip_mc_find_dev(&imr);
1873 
1874 	if (!in_dev) {
1875 		err = -ENODEV;
1876 		goto done;
1877 	}
1878 	err = -EADDRNOTAVAIL;
1879 
1880 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
1881 		if (pmc->multi.imr_multiaddr.s_addr == imr.imr_multiaddr.s_addr
1882 		    && pmc->multi.imr_ifindex == imr.imr_ifindex)
1883 			break;
1884 	}
1885 	if (!pmc) {		/* must have a prior join */
1886 		err = -EINVAL;
1887 		goto done;
1888 	}
1889 	/* if a source filter was set, must be the same mode as before */
1890 	if (pmc->sflist) {
1891 		if (pmc->sfmode != omode) {
1892 			err = -EINVAL;
1893 			goto done;
1894 		}
1895 	} else if (pmc->sfmode != omode) {
1896 		/* allow mode switches for empty-set filters */
1897 		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
1898 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
1899 			NULL, 0);
1900 		pmc->sfmode = omode;
1901 	}
1902 
1903 	psl = pmc->sflist;
1904 	if (!add) {
1905 		if (!psl)
1906 			goto done;	/* err = -EADDRNOTAVAIL */
1907 		rv = !0;
1908 		for (i=0; i<psl->sl_count; i++) {
1909 			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1910 				sizeof(__be32));
1911 			if (rv == 0)
1912 				break;
1913 		}
1914 		if (rv)		/* source not found */
1915 			goto done;	/* err = -EADDRNOTAVAIL */
1916 
1917 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
1918 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
1919 			leavegroup = 1;
1920 			goto done;
1921 		}
1922 
1923 		/* update the interface filter */
1924 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1925 			&mreqs->imr_sourceaddr, 1);
1926 
1927 		for (j=i+1; j<psl->sl_count; j++)
1928 			psl->sl_addr[j-1] = psl->sl_addr[j];
1929 		psl->sl_count--;
1930 		err = 0;
1931 		goto done;
1932 	}
1933 	/* else, add a new source to the filter */
1934 
1935 	if (psl && psl->sl_count >= sysctl_igmp_max_msf) {
1936 		err = -ENOBUFS;
1937 		goto done;
1938 	}
1939 	if (!psl || psl->sl_count == psl->sl_max) {
1940 		struct ip_sf_socklist *newpsl;
1941 		int count = IP_SFBLOCK;
1942 
1943 		if (psl)
1944 			count += psl->sl_max;
1945 		newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
1946 		if (!newpsl) {
1947 			err = -ENOBUFS;
1948 			goto done;
1949 		}
1950 		newpsl->sl_max = count;
1951 		newpsl->sl_count = count - IP_SFBLOCK;
1952 		if (psl) {
1953 			for (i=0; i<psl->sl_count; i++)
1954 				newpsl->sl_addr[i] = psl->sl_addr[i];
1955 			sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
1956 		}
1957 		pmc->sflist = psl = newpsl;
1958 	}
1959 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
1960 	for (i=0; i<psl->sl_count; i++) {
1961 		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1962 			sizeof(__be32));
1963 		if (rv == 0)
1964 			break;
1965 	}
1966 	if (rv == 0)		/* address already there is an error */
1967 		goto done;
1968 	for (j=psl->sl_count-1; j>=i; j--)
1969 		psl->sl_addr[j+1] = psl->sl_addr[j];
1970 	psl->sl_addr[i] = mreqs->imr_sourceaddr;
1971 	psl->sl_count++;
1972 	err = 0;
1973 	/* update the interface list */
1974 	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1975 		&mreqs->imr_sourceaddr, 1);
1976 done:
1977 	rtnl_unlock();
1978 	if (leavegroup)
1979 		return ip_mc_leave_group(sk, &imr);
1980 	return err;
1981 }
1982 
1983 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
1984 {
1985 	int err = 0;
1986 	struct ip_mreqn	imr;
1987 	__be32 addr = msf->imsf_multiaddr;
1988 	struct ip_mc_socklist *pmc;
1989 	struct in_device *in_dev;
1990 	struct inet_sock *inet = inet_sk(sk);
1991 	struct ip_sf_socklist *newpsl, *psl;
1992 	int leavegroup = 0;
1993 
1994 	if (!MULTICAST(addr))
1995 		return -EINVAL;
1996 	if (msf->imsf_fmode != MCAST_INCLUDE &&
1997 	    msf->imsf_fmode != MCAST_EXCLUDE)
1998 		return -EINVAL;
1999 
2000 	rtnl_lock();
2001 
2002 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2003 	imr.imr_address.s_addr = msf->imsf_interface;
2004 	imr.imr_ifindex = ifindex;
2005 	in_dev = ip_mc_find_dev(&imr);
2006 
2007 	if (!in_dev) {
2008 		err = -ENODEV;
2009 		goto done;
2010 	}
2011 
2012 	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2013 	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2014 		leavegroup = 1;
2015 		goto done;
2016 	}
2017 
2018 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2019 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2020 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2021 			break;
2022 	}
2023 	if (!pmc) {		/* must have a prior join */
2024 		err = -EINVAL;
2025 		goto done;
2026 	}
2027 	if (msf->imsf_numsrc) {
2028 		newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2029 							   GFP_KERNEL);
2030 		if (!newpsl) {
2031 			err = -ENOBUFS;
2032 			goto done;
2033 		}
2034 		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2035 		memcpy(newpsl->sl_addr, msf->imsf_slist,
2036 			msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2037 		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2038 			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2039 		if (err) {
2040 			sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2041 			goto done;
2042 		}
2043 	} else {
2044 		newpsl = NULL;
2045 		(void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2046 				     msf->imsf_fmode, 0, NULL, 0);
2047 	}
2048 	psl = pmc->sflist;
2049 	if (psl) {
2050 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2051 			psl->sl_count, psl->sl_addr, 0);
2052 		sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
2053 	} else
2054 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2055 			0, NULL, 0);
2056 	pmc->sflist = newpsl;
2057 	pmc->sfmode = msf->imsf_fmode;
2058 	err = 0;
2059 done:
2060 	rtnl_unlock();
2061 	if (leavegroup)
2062 		err = ip_mc_leave_group(sk, &imr);
2063 	return err;
2064 }
2065 
2066 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2067 	struct ip_msfilter __user *optval, int __user *optlen)
2068 {
2069 	int err, len, count, copycount;
2070 	struct ip_mreqn	imr;
2071 	__be32 addr = msf->imsf_multiaddr;
2072 	struct ip_mc_socklist *pmc;
2073 	struct in_device *in_dev;
2074 	struct inet_sock *inet = inet_sk(sk);
2075 	struct ip_sf_socklist *psl;
2076 
2077 	if (!MULTICAST(addr))
2078 		return -EINVAL;
2079 
2080 	rtnl_lock();
2081 
2082 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2083 	imr.imr_address.s_addr = msf->imsf_interface;
2084 	imr.imr_ifindex = 0;
2085 	in_dev = ip_mc_find_dev(&imr);
2086 
2087 	if (!in_dev) {
2088 		err = -ENODEV;
2089 		goto done;
2090 	}
2091 	err = -EADDRNOTAVAIL;
2092 
2093 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2094 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2095 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2096 			break;
2097 	}
2098 	if (!pmc)		/* must have a prior join */
2099 		goto done;
2100 	msf->imsf_fmode = pmc->sfmode;
2101 	psl = pmc->sflist;
2102 	rtnl_unlock();
2103 	if (!psl) {
2104 		len = 0;
2105 		count = 0;
2106 	} else {
2107 		count = psl->sl_count;
2108 	}
2109 	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2110 	len = copycount * sizeof(psl->sl_addr[0]);
2111 	msf->imsf_numsrc = count;
2112 	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2113 	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2114 		return -EFAULT;
2115 	}
2116 	if (len &&
2117 	    copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2118 		return -EFAULT;
2119 	return 0;
2120 done:
2121 	rtnl_unlock();
2122 	return err;
2123 }
2124 
2125 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2126 	struct group_filter __user *optval, int __user *optlen)
2127 {
2128 	int err, i, count, copycount;
2129 	struct sockaddr_in *psin;
2130 	__be32 addr;
2131 	struct ip_mc_socklist *pmc;
2132 	struct inet_sock *inet = inet_sk(sk);
2133 	struct ip_sf_socklist *psl;
2134 
2135 	psin = (struct sockaddr_in *)&gsf->gf_group;
2136 	if (psin->sin_family != AF_INET)
2137 		return -EINVAL;
2138 	addr = psin->sin_addr.s_addr;
2139 	if (!MULTICAST(addr))
2140 		return -EINVAL;
2141 
2142 	rtnl_lock();
2143 
2144 	err = -EADDRNOTAVAIL;
2145 
2146 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2147 		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2148 		    pmc->multi.imr_ifindex == gsf->gf_interface)
2149 			break;
2150 	}
2151 	if (!pmc)		/* must have a prior join */
2152 		goto done;
2153 	gsf->gf_fmode = pmc->sfmode;
2154 	psl = pmc->sflist;
2155 	rtnl_unlock();
2156 	count = psl ? psl->sl_count : 0;
2157 	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2158 	gsf->gf_numsrc = count;
2159 	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2160 	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2161 		return -EFAULT;
2162 	}
2163 	for (i=0; i<copycount; i++) {
2164 		struct sockaddr_in *psin;
2165 		struct sockaddr_storage ss;
2166 
2167 		psin = (struct sockaddr_in *)&ss;
2168 		memset(&ss, 0, sizeof(ss));
2169 		psin->sin_family = AF_INET;
2170 		psin->sin_addr.s_addr = psl->sl_addr[i];
2171 		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2172 			return -EFAULT;
2173 	}
2174 	return 0;
2175 done:
2176 	rtnl_unlock();
2177 	return err;
2178 }
2179 
2180 /*
2181  * check if a multicast source filter allows delivery for a given <src,dst,intf>
2182  */
2183 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif)
2184 {
2185 	struct inet_sock *inet = inet_sk(sk);
2186 	struct ip_mc_socklist *pmc;
2187 	struct ip_sf_socklist *psl;
2188 	int i;
2189 
2190 	if (!MULTICAST(loc_addr))
2191 		return 1;
2192 
2193 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2194 		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2195 		    pmc->multi.imr_ifindex == dif)
2196 			break;
2197 	}
2198 	if (!pmc)
2199 		return 1;
2200 	psl = pmc->sflist;
2201 	if (!psl)
2202 		return pmc->sfmode == MCAST_EXCLUDE;
2203 
2204 	for (i=0; i<psl->sl_count; i++) {
2205 		if (psl->sl_addr[i] == rmt_addr)
2206 			break;
2207 	}
2208 	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2209 		return 0;
2210 	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2211 		return 0;
2212 	return 1;
2213 }
2214 
2215 /*
2216  *	A socket is closing.
2217  */
2218 
2219 void ip_mc_drop_socket(struct sock *sk)
2220 {
2221 	struct inet_sock *inet = inet_sk(sk);
2222 	struct ip_mc_socklist *iml;
2223 
2224 	if (inet->mc_list == NULL)
2225 		return;
2226 
2227 	rtnl_lock();
2228 	while ((iml = inet->mc_list) != NULL) {
2229 		struct in_device *in_dev;
2230 		inet->mc_list = iml->next;
2231 
2232 		in_dev = inetdev_by_index(iml->multi.imr_ifindex);
2233 		(void) ip_mc_leave_src(sk, iml, in_dev);
2234 		if (in_dev != NULL) {
2235 			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2236 			in_dev_put(in_dev);
2237 		}
2238 		sock_kfree_s(sk, iml, sizeof(*iml));
2239 	}
2240 	rtnl_unlock();
2241 }
2242 
2243 int ip_check_mc(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u16 proto)
2244 {
2245 	struct ip_mc_list *im;
2246 	struct ip_sf_list *psf;
2247 	int rv = 0;
2248 
2249 	read_lock(&in_dev->mc_list_lock);
2250 	for (im=in_dev->mc_list; im; im=im->next) {
2251 		if (im->multiaddr == mc_addr)
2252 			break;
2253 	}
2254 	if (im && proto == IPPROTO_IGMP) {
2255 		rv = 1;
2256 	} else if (im) {
2257 		if (src_addr) {
2258 			for (psf=im->sources; psf; psf=psf->sf_next) {
2259 				if (psf->sf_inaddr == src_addr)
2260 					break;
2261 			}
2262 			if (psf)
2263 				rv = psf->sf_count[MCAST_INCLUDE] ||
2264 					psf->sf_count[MCAST_EXCLUDE] !=
2265 					im->sfcount[MCAST_EXCLUDE];
2266 			else
2267 				rv = im->sfcount[MCAST_EXCLUDE] != 0;
2268 		} else
2269 			rv = 1; /* unspecified source; tentatively allow */
2270 	}
2271 	read_unlock(&in_dev->mc_list_lock);
2272 	return rv;
2273 }
2274 
2275 #if defined(CONFIG_PROC_FS)
2276 struct igmp_mc_iter_state {
2277 	struct net_device *dev;
2278 	struct in_device *in_dev;
2279 };
2280 
2281 #define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2282 
2283 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2284 {
2285 	struct ip_mc_list *im = NULL;
2286 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2287 
2288 	for (state->dev = dev_base, state->in_dev = NULL;
2289 	     state->dev;
2290 	     state->dev = state->dev->next) {
2291 		struct in_device *in_dev;
2292 		in_dev = in_dev_get(state->dev);
2293 		if (!in_dev)
2294 			continue;
2295 		read_lock(&in_dev->mc_list_lock);
2296 		im = in_dev->mc_list;
2297 		if (im) {
2298 			state->in_dev = in_dev;
2299 			break;
2300 		}
2301 		read_unlock(&in_dev->mc_list_lock);
2302 		in_dev_put(in_dev);
2303 	}
2304 	return im;
2305 }
2306 
2307 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2308 {
2309 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2310 	im = im->next;
2311 	while (!im) {
2312 		if (likely(state->in_dev != NULL)) {
2313 			read_unlock(&state->in_dev->mc_list_lock);
2314 			in_dev_put(state->in_dev);
2315 		}
2316 		state->dev = state->dev->next;
2317 		if (!state->dev) {
2318 			state->in_dev = NULL;
2319 			break;
2320 		}
2321 		state->in_dev = in_dev_get(state->dev);
2322 		if (!state->in_dev)
2323 			continue;
2324 		read_lock(&state->in_dev->mc_list_lock);
2325 		im = state->in_dev->mc_list;
2326 	}
2327 	return im;
2328 }
2329 
2330 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2331 {
2332 	struct ip_mc_list *im = igmp_mc_get_first(seq);
2333 	if (im)
2334 		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2335 			--pos;
2336 	return pos ? NULL : im;
2337 }
2338 
2339 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2340 {
2341 	read_lock(&dev_base_lock);
2342 	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2343 }
2344 
2345 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2346 {
2347 	struct ip_mc_list *im;
2348 	if (v == SEQ_START_TOKEN)
2349 		im = igmp_mc_get_first(seq);
2350 	else
2351 		im = igmp_mc_get_next(seq, v);
2352 	++*pos;
2353 	return im;
2354 }
2355 
2356 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2357 {
2358 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2359 	if (likely(state->in_dev != NULL)) {
2360 		read_unlock(&state->in_dev->mc_list_lock);
2361 		in_dev_put(state->in_dev);
2362 		state->in_dev = NULL;
2363 	}
2364 	state->dev = NULL;
2365 	read_unlock(&dev_base_lock);
2366 }
2367 
2368 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2369 {
2370 	if (v == SEQ_START_TOKEN)
2371 		seq_puts(seq,
2372 			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2373 	else {
2374 		struct ip_mc_list *im = (struct ip_mc_list *)v;
2375 		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2376 		char   *querier;
2377 #ifdef CONFIG_IP_MULTICAST
2378 		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2379 			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2380 			  "V3";
2381 #else
2382 		querier = "NONE";
2383 #endif
2384 
2385 		if (state->in_dev->mc_list == im) {
2386 			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2387 				   state->dev->ifindex, state->dev->name, state->dev->mc_count, querier);
2388 		}
2389 
2390 		seq_printf(seq,
2391 			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2392 			   im->multiaddr, im->users,
2393 			   im->tm_running, im->tm_running ?
2394 			   jiffies_to_clock_t(im->timer.expires-jiffies) : 0,
2395 			   im->reporter);
2396 	}
2397 	return 0;
2398 }
2399 
2400 static struct seq_operations igmp_mc_seq_ops = {
2401 	.start	=	igmp_mc_seq_start,
2402 	.next	=	igmp_mc_seq_next,
2403 	.stop	=	igmp_mc_seq_stop,
2404 	.show	=	igmp_mc_seq_show,
2405 };
2406 
2407 static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2408 {
2409 	struct seq_file *seq;
2410 	int rc = -ENOMEM;
2411 	struct igmp_mc_iter_state *s = kzalloc(sizeof(*s), GFP_KERNEL);
2412 
2413 	if (!s)
2414 		goto out;
2415 	rc = seq_open(file, &igmp_mc_seq_ops);
2416 	if (rc)
2417 		goto out_kfree;
2418 
2419 	seq = file->private_data;
2420 	seq->private = s;
2421 out:
2422 	return rc;
2423 out_kfree:
2424 	kfree(s);
2425 	goto out;
2426 }
2427 
2428 static const struct file_operations igmp_mc_seq_fops = {
2429 	.owner		=	THIS_MODULE,
2430 	.open		=	igmp_mc_seq_open,
2431 	.read		=	seq_read,
2432 	.llseek		=	seq_lseek,
2433 	.release	=	seq_release_private,
2434 };
2435 
2436 struct igmp_mcf_iter_state {
2437 	struct net_device *dev;
2438 	struct in_device *idev;
2439 	struct ip_mc_list *im;
2440 };
2441 
2442 #define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2443 
2444 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2445 {
2446 	struct ip_sf_list *psf = NULL;
2447 	struct ip_mc_list *im = NULL;
2448 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2449 
2450 	for (state->dev = dev_base, state->idev = NULL, state->im = NULL;
2451 	     state->dev;
2452 	     state->dev = state->dev->next) {
2453 		struct in_device *idev;
2454 		idev = in_dev_get(state->dev);
2455 		if (unlikely(idev == NULL))
2456 			continue;
2457 		read_lock(&idev->mc_list_lock);
2458 		im = idev->mc_list;
2459 		if (likely(im != NULL)) {
2460 			spin_lock_bh(&im->lock);
2461 			psf = im->sources;
2462 			if (likely(psf != NULL)) {
2463 				state->im = im;
2464 				state->idev = idev;
2465 				break;
2466 			}
2467 			spin_unlock_bh(&im->lock);
2468 		}
2469 		read_unlock(&idev->mc_list_lock);
2470 		in_dev_put(idev);
2471 	}
2472 	return psf;
2473 }
2474 
2475 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2476 {
2477 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2478 
2479 	psf = psf->sf_next;
2480 	while (!psf) {
2481 		spin_unlock_bh(&state->im->lock);
2482 		state->im = state->im->next;
2483 		while (!state->im) {
2484 			if (likely(state->idev != NULL)) {
2485 				read_unlock(&state->idev->mc_list_lock);
2486 				in_dev_put(state->idev);
2487 			}
2488 			state->dev = state->dev->next;
2489 			if (!state->dev) {
2490 				state->idev = NULL;
2491 				goto out;
2492 			}
2493 			state->idev = in_dev_get(state->dev);
2494 			if (!state->idev)
2495 				continue;
2496 			read_lock(&state->idev->mc_list_lock);
2497 			state->im = state->idev->mc_list;
2498 		}
2499 		if (!state->im)
2500 			break;
2501 		spin_lock_bh(&state->im->lock);
2502 		psf = state->im->sources;
2503 	}
2504 out:
2505 	return psf;
2506 }
2507 
2508 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2509 {
2510 	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2511 	if (psf)
2512 		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2513 			--pos;
2514 	return pos ? NULL : psf;
2515 }
2516 
2517 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2518 {
2519 	read_lock(&dev_base_lock);
2520 	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2521 }
2522 
2523 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2524 {
2525 	struct ip_sf_list *psf;
2526 	if (v == SEQ_START_TOKEN)
2527 		psf = igmp_mcf_get_first(seq);
2528 	else
2529 		psf = igmp_mcf_get_next(seq, v);
2530 	++*pos;
2531 	return psf;
2532 }
2533 
2534 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2535 {
2536 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2537 	if (likely(state->im != NULL)) {
2538 		spin_unlock_bh(&state->im->lock);
2539 		state->im = NULL;
2540 	}
2541 	if (likely(state->idev != NULL)) {
2542 		read_unlock(&state->idev->mc_list_lock);
2543 		in_dev_put(state->idev);
2544 		state->idev = NULL;
2545 	}
2546 	state->dev = NULL;
2547 	read_unlock(&dev_base_lock);
2548 }
2549 
2550 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2551 {
2552 	struct ip_sf_list *psf = (struct ip_sf_list *)v;
2553 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2554 
2555 	if (v == SEQ_START_TOKEN) {
2556 		seq_printf(seq,
2557 			   "%3s %6s "
2558 			   "%10s %10s %6s %6s\n", "Idx",
2559 			   "Device", "MCA",
2560 			   "SRC", "INC", "EXC");
2561 	} else {
2562 		seq_printf(seq,
2563 			   "%3d %6.6s 0x%08x "
2564 			   "0x%08x %6lu %6lu\n",
2565 			   state->dev->ifindex, state->dev->name,
2566 			   ntohl(state->im->multiaddr),
2567 			   ntohl(psf->sf_inaddr),
2568 			   psf->sf_count[MCAST_INCLUDE],
2569 			   psf->sf_count[MCAST_EXCLUDE]);
2570 	}
2571 	return 0;
2572 }
2573 
2574 static struct seq_operations igmp_mcf_seq_ops = {
2575 	.start	=	igmp_mcf_seq_start,
2576 	.next	=	igmp_mcf_seq_next,
2577 	.stop	=	igmp_mcf_seq_stop,
2578 	.show	=	igmp_mcf_seq_show,
2579 };
2580 
2581 static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2582 {
2583 	struct seq_file *seq;
2584 	int rc = -ENOMEM;
2585 	struct igmp_mcf_iter_state *s = kzalloc(sizeof(*s), GFP_KERNEL);
2586 
2587 	if (!s)
2588 		goto out;
2589 	rc = seq_open(file, &igmp_mcf_seq_ops);
2590 	if (rc)
2591 		goto out_kfree;
2592 
2593 	seq = file->private_data;
2594 	seq->private = s;
2595 out:
2596 	return rc;
2597 out_kfree:
2598 	kfree(s);
2599 	goto out;
2600 }
2601 
2602 static const struct file_operations igmp_mcf_seq_fops = {
2603 	.owner		=	THIS_MODULE,
2604 	.open		=	igmp_mcf_seq_open,
2605 	.read		=	seq_read,
2606 	.llseek		=	seq_lseek,
2607 	.release	=	seq_release_private,
2608 };
2609 
2610 int __init igmp_mc_proc_init(void)
2611 {
2612 	proc_net_fops_create("igmp", S_IRUGO, &igmp_mc_seq_fops);
2613 	proc_net_fops_create("mcfilter", S_IRUGO, &igmp_mcf_seq_fops);
2614 	return 0;
2615 }
2616 #endif
2617 
2618 EXPORT_SYMBOL(ip_mc_dec_group);
2619 EXPORT_SYMBOL(ip_mc_inc_group);
2620 EXPORT_SYMBOL(ip_mc_join_group);
2621 EXPORT_SYMBOL(ip_mc_rejoin_group);
2622