xref: /linux/net/ipv4/igmp.c (revision cd354f1ae75e6466a7e31b727faede57a1f89ca5)
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  *	A socket has left a multicast group on device dev
1255  */
1256 
1257 void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
1258 {
1259 	struct ip_mc_list *i, **ip;
1260 
1261 	ASSERT_RTNL();
1262 
1263 	for (ip=&in_dev->mc_list; (i=*ip)!=NULL; ip=&i->next) {
1264 		if (i->multiaddr==addr) {
1265 			if (--i->users == 0) {
1266 				write_lock_bh(&in_dev->mc_list_lock);
1267 				*ip = i->next;
1268 				write_unlock_bh(&in_dev->mc_list_lock);
1269 				igmp_group_dropped(i);
1270 
1271 				if (!in_dev->dead)
1272 					ip_rt_multicast_event(in_dev);
1273 
1274 				ip_ma_put(i);
1275 				return;
1276 			}
1277 			break;
1278 		}
1279 	}
1280 }
1281 
1282 /* Device going down */
1283 
1284 void ip_mc_down(struct in_device *in_dev)
1285 {
1286 	struct ip_mc_list *i;
1287 
1288 	ASSERT_RTNL();
1289 
1290 	for (i=in_dev->mc_list; i; i=i->next)
1291 		igmp_group_dropped(i);
1292 
1293 #ifdef CONFIG_IP_MULTICAST
1294 	in_dev->mr_ifc_count = 0;
1295 	if (del_timer(&in_dev->mr_ifc_timer))
1296 		__in_dev_put(in_dev);
1297 	in_dev->mr_gq_running = 0;
1298 	if (del_timer(&in_dev->mr_gq_timer))
1299 		__in_dev_put(in_dev);
1300 	igmpv3_clear_delrec(in_dev);
1301 #endif
1302 
1303 	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1304 }
1305 
1306 void ip_mc_init_dev(struct in_device *in_dev)
1307 {
1308 	ASSERT_RTNL();
1309 
1310 	in_dev->mc_tomb = NULL;
1311 #ifdef CONFIG_IP_MULTICAST
1312 	in_dev->mr_gq_running = 0;
1313 	init_timer(&in_dev->mr_gq_timer);
1314 	in_dev->mr_gq_timer.data=(unsigned long) in_dev;
1315 	in_dev->mr_gq_timer.function=&igmp_gq_timer_expire;
1316 	in_dev->mr_ifc_count = 0;
1317 	init_timer(&in_dev->mr_ifc_timer);
1318 	in_dev->mr_ifc_timer.data=(unsigned long) in_dev;
1319 	in_dev->mr_ifc_timer.function=&igmp_ifc_timer_expire;
1320 	in_dev->mr_qrv = IGMP_Unsolicited_Report_Count;
1321 #endif
1322 
1323 	rwlock_init(&in_dev->mc_list_lock);
1324 	spin_lock_init(&in_dev->mc_tomb_lock);
1325 }
1326 
1327 /* Device going up */
1328 
1329 void ip_mc_up(struct in_device *in_dev)
1330 {
1331 	struct ip_mc_list *i;
1332 
1333 	ASSERT_RTNL();
1334 
1335 	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1336 
1337 	for (i=in_dev->mc_list; i; i=i->next)
1338 		igmp_group_added(i);
1339 }
1340 
1341 /*
1342  *	Device is about to be destroyed: clean up.
1343  */
1344 
1345 void ip_mc_destroy_dev(struct in_device *in_dev)
1346 {
1347 	struct ip_mc_list *i;
1348 
1349 	ASSERT_RTNL();
1350 
1351 	/* Deactivate timers */
1352 	ip_mc_down(in_dev);
1353 
1354 	write_lock_bh(&in_dev->mc_list_lock);
1355 	while ((i = in_dev->mc_list) != NULL) {
1356 		in_dev->mc_list = i->next;
1357 		write_unlock_bh(&in_dev->mc_list_lock);
1358 
1359 		igmp_group_dropped(i);
1360 		ip_ma_put(i);
1361 
1362 		write_lock_bh(&in_dev->mc_list_lock);
1363 	}
1364 	write_unlock_bh(&in_dev->mc_list_lock);
1365 }
1366 
1367 static struct in_device * ip_mc_find_dev(struct ip_mreqn *imr)
1368 {
1369 	struct flowi fl = { .nl_u = { .ip4_u =
1370 				      { .daddr = imr->imr_multiaddr.s_addr } } };
1371 	struct rtable *rt;
1372 	struct net_device *dev = NULL;
1373 	struct in_device *idev = NULL;
1374 
1375 	if (imr->imr_ifindex) {
1376 		idev = inetdev_by_index(imr->imr_ifindex);
1377 		if (idev)
1378 			__in_dev_put(idev);
1379 		return idev;
1380 	}
1381 	if (imr->imr_address.s_addr) {
1382 		dev = ip_dev_find(imr->imr_address.s_addr);
1383 		if (!dev)
1384 			return NULL;
1385 		dev_put(dev);
1386 	}
1387 
1388 	if (!dev && !ip_route_output_key(&rt, &fl)) {
1389 		dev = rt->u.dst.dev;
1390 		ip_rt_put(rt);
1391 	}
1392 	if (dev) {
1393 		imr->imr_ifindex = dev->ifindex;
1394 		idev = __in_dev_get_rtnl(dev);
1395 	}
1396 	return idev;
1397 }
1398 
1399 /*
1400  *	Join a socket to a group
1401  */
1402 int sysctl_igmp_max_memberships __read_mostly = IP_MAX_MEMBERSHIPS;
1403 int sysctl_igmp_max_msf __read_mostly = IP_MAX_MSF;
1404 
1405 
1406 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1407 	__be32 *psfsrc)
1408 {
1409 	struct ip_sf_list *psf, *psf_prev;
1410 	int rv = 0;
1411 
1412 	psf_prev = NULL;
1413 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1414 		if (psf->sf_inaddr == *psfsrc)
1415 			break;
1416 		psf_prev = psf;
1417 	}
1418 	if (!psf || psf->sf_count[sfmode] == 0) {
1419 		/* source filter not found, or count wrong =>  bug */
1420 		return -ESRCH;
1421 	}
1422 	psf->sf_count[sfmode]--;
1423 	if (psf->sf_count[sfmode] == 0) {
1424 		ip_rt_multicast_event(pmc->interface);
1425 	}
1426 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1427 #ifdef CONFIG_IP_MULTICAST
1428 		struct in_device *in_dev = pmc->interface;
1429 #endif
1430 
1431 		/* no more filters for this source */
1432 		if (psf_prev)
1433 			psf_prev->sf_next = psf->sf_next;
1434 		else
1435 			pmc->sources = psf->sf_next;
1436 #ifdef CONFIG_IP_MULTICAST
1437 		if (psf->sf_oldin &&
1438 		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1439 			psf->sf_crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1440 				IGMP_Unsolicited_Report_Count;
1441 			psf->sf_next = pmc->tomb;
1442 			pmc->tomb = psf;
1443 			rv = 1;
1444 		} else
1445 #endif
1446 			kfree(psf);
1447 	}
1448 	return rv;
1449 }
1450 
1451 #ifndef CONFIG_IP_MULTICAST
1452 #define igmp_ifc_event(x)	do { } while (0)
1453 #endif
1454 
1455 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1456 			 int sfcount, __be32 *psfsrc, int delta)
1457 {
1458 	struct ip_mc_list *pmc;
1459 	int	changerec = 0;
1460 	int	i, err;
1461 
1462 	if (!in_dev)
1463 		return -ENODEV;
1464 	read_lock(&in_dev->mc_list_lock);
1465 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1466 		if (*pmca == pmc->multiaddr)
1467 			break;
1468 	}
1469 	if (!pmc) {
1470 		/* MCA not found?? bug */
1471 		read_unlock(&in_dev->mc_list_lock);
1472 		return -ESRCH;
1473 	}
1474 	spin_lock_bh(&pmc->lock);
1475 	read_unlock(&in_dev->mc_list_lock);
1476 #ifdef CONFIG_IP_MULTICAST
1477 	sf_markstate(pmc);
1478 #endif
1479 	if (!delta) {
1480 		err = -EINVAL;
1481 		if (!pmc->sfcount[sfmode])
1482 			goto out_unlock;
1483 		pmc->sfcount[sfmode]--;
1484 	}
1485 	err = 0;
1486 	for (i=0; i<sfcount; i++) {
1487 		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1488 
1489 		changerec |= rv > 0;
1490 		if (!err && rv < 0)
1491 			err = rv;
1492 	}
1493 	if (pmc->sfmode == MCAST_EXCLUDE &&
1494 	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1495 	    pmc->sfcount[MCAST_INCLUDE]) {
1496 #ifdef CONFIG_IP_MULTICAST
1497 		struct ip_sf_list *psf;
1498 #endif
1499 
1500 		/* filter mode change */
1501 		pmc->sfmode = MCAST_INCLUDE;
1502 #ifdef CONFIG_IP_MULTICAST
1503 		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1504 			IGMP_Unsolicited_Report_Count;
1505 		in_dev->mr_ifc_count = pmc->crcount;
1506 		for (psf=pmc->sources; psf; psf = psf->sf_next)
1507 			psf->sf_crcount = 0;
1508 		igmp_ifc_event(pmc->interface);
1509 	} else if (sf_setstate(pmc) || changerec) {
1510 		igmp_ifc_event(pmc->interface);
1511 #endif
1512 	}
1513 out_unlock:
1514 	spin_unlock_bh(&pmc->lock);
1515 	return err;
1516 }
1517 
1518 /*
1519  * Add multicast single-source filter to the interface list
1520  */
1521 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1522 	__be32 *psfsrc, int delta)
1523 {
1524 	struct ip_sf_list *psf, *psf_prev;
1525 
1526 	psf_prev = NULL;
1527 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1528 		if (psf->sf_inaddr == *psfsrc)
1529 			break;
1530 		psf_prev = psf;
1531 	}
1532 	if (!psf) {
1533 		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1534 		if (!psf)
1535 			return -ENOBUFS;
1536 		psf->sf_inaddr = *psfsrc;
1537 		if (psf_prev) {
1538 			psf_prev->sf_next = psf;
1539 		} else
1540 			pmc->sources = psf;
1541 	}
1542 	psf->sf_count[sfmode]++;
1543 	if (psf->sf_count[sfmode] == 1) {
1544 		ip_rt_multicast_event(pmc->interface);
1545 	}
1546 	return 0;
1547 }
1548 
1549 #ifdef CONFIG_IP_MULTICAST
1550 static void sf_markstate(struct ip_mc_list *pmc)
1551 {
1552 	struct ip_sf_list *psf;
1553 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1554 
1555 	for (psf=pmc->sources; psf; psf=psf->sf_next)
1556 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1557 			psf->sf_oldin = mca_xcount ==
1558 				psf->sf_count[MCAST_EXCLUDE] &&
1559 				!psf->sf_count[MCAST_INCLUDE];
1560 		} else
1561 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1562 }
1563 
1564 static int sf_setstate(struct ip_mc_list *pmc)
1565 {
1566 	struct ip_sf_list *psf, *dpsf;
1567 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1568 	int qrv = pmc->interface->mr_qrv;
1569 	int new_in, rv;
1570 
1571 	rv = 0;
1572 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1573 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1574 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1575 				!psf->sf_count[MCAST_INCLUDE];
1576 		} else
1577 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1578 		if (new_in) {
1579 			if (!psf->sf_oldin) {
1580 				struct ip_sf_list *prev = NULL;
1581 
1582 				for (dpsf=pmc->tomb; dpsf; dpsf=dpsf->sf_next) {
1583 					if (dpsf->sf_inaddr == psf->sf_inaddr)
1584 						break;
1585 					prev = dpsf;
1586 				}
1587 				if (dpsf) {
1588 					if (prev)
1589 						prev->sf_next = dpsf->sf_next;
1590 					else
1591 						pmc->tomb = dpsf->sf_next;
1592 					kfree(dpsf);
1593 				}
1594 				psf->sf_crcount = qrv;
1595 				rv++;
1596 			}
1597 		} else if (psf->sf_oldin) {
1598 
1599 			psf->sf_crcount = 0;
1600 			/*
1601 			 * add or update "delete" records if an active filter
1602 			 * is now inactive
1603 			 */
1604 			for (dpsf=pmc->tomb; dpsf; dpsf=dpsf->sf_next)
1605 				if (dpsf->sf_inaddr == psf->sf_inaddr)
1606 					break;
1607 			if (!dpsf) {
1608 				dpsf = (struct ip_sf_list *)
1609 					kmalloc(sizeof(*dpsf), GFP_ATOMIC);
1610 				if (!dpsf)
1611 					continue;
1612 				*dpsf = *psf;
1613 				/* pmc->lock held by callers */
1614 				dpsf->sf_next = pmc->tomb;
1615 				pmc->tomb = dpsf;
1616 			}
1617 			dpsf->sf_crcount = qrv;
1618 			rv++;
1619 		}
1620 	}
1621 	return rv;
1622 }
1623 #endif
1624 
1625 /*
1626  * Add multicast source filter list to the interface list
1627  */
1628 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1629 			 int sfcount, __be32 *psfsrc, int delta)
1630 {
1631 	struct ip_mc_list *pmc;
1632 	int	isexclude;
1633 	int	i, err;
1634 
1635 	if (!in_dev)
1636 		return -ENODEV;
1637 	read_lock(&in_dev->mc_list_lock);
1638 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1639 		if (*pmca == pmc->multiaddr)
1640 			break;
1641 	}
1642 	if (!pmc) {
1643 		/* MCA not found?? bug */
1644 		read_unlock(&in_dev->mc_list_lock);
1645 		return -ESRCH;
1646 	}
1647 	spin_lock_bh(&pmc->lock);
1648 	read_unlock(&in_dev->mc_list_lock);
1649 
1650 #ifdef CONFIG_IP_MULTICAST
1651 	sf_markstate(pmc);
1652 #endif
1653 	isexclude = pmc->sfmode == MCAST_EXCLUDE;
1654 	if (!delta)
1655 		pmc->sfcount[sfmode]++;
1656 	err = 0;
1657 	for (i=0; i<sfcount; i++) {
1658 		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i], delta);
1659 		if (err)
1660 			break;
1661 	}
1662 	if (err) {
1663 		int j;
1664 
1665 		pmc->sfcount[sfmode]--;
1666 		for (j=0; j<i; j++)
1667 			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1668 	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
1669 #ifdef CONFIG_IP_MULTICAST
1670 		struct in_device *in_dev = pmc->interface;
1671 		struct ip_sf_list *psf;
1672 #endif
1673 
1674 		/* filter mode change */
1675 		if (pmc->sfcount[MCAST_EXCLUDE])
1676 			pmc->sfmode = MCAST_EXCLUDE;
1677 		else if (pmc->sfcount[MCAST_INCLUDE])
1678 			pmc->sfmode = MCAST_INCLUDE;
1679 #ifdef CONFIG_IP_MULTICAST
1680 		/* else no filters; keep old mode for reports */
1681 
1682 		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1683 			IGMP_Unsolicited_Report_Count;
1684 		in_dev->mr_ifc_count = pmc->crcount;
1685 		for (psf=pmc->sources; psf; psf = psf->sf_next)
1686 			psf->sf_crcount = 0;
1687 		igmp_ifc_event(in_dev);
1688 	} else if (sf_setstate(pmc)) {
1689 		igmp_ifc_event(in_dev);
1690 #endif
1691 	}
1692 	spin_unlock_bh(&pmc->lock);
1693 	return err;
1694 }
1695 
1696 static void ip_mc_clear_src(struct ip_mc_list *pmc)
1697 {
1698 	struct ip_sf_list *psf, *nextpsf;
1699 
1700 	for (psf=pmc->tomb; psf; psf=nextpsf) {
1701 		nextpsf = psf->sf_next;
1702 		kfree(psf);
1703 	}
1704 	pmc->tomb = NULL;
1705 	for (psf=pmc->sources; psf; psf=nextpsf) {
1706 		nextpsf = psf->sf_next;
1707 		kfree(psf);
1708 	}
1709 	pmc->sources = NULL;
1710 	pmc->sfmode = MCAST_EXCLUDE;
1711 	pmc->sfcount[MCAST_INCLUDE] = 0;
1712 	pmc->sfcount[MCAST_EXCLUDE] = 1;
1713 }
1714 
1715 
1716 /*
1717  * Join a multicast group
1718  */
1719 int ip_mc_join_group(struct sock *sk , struct ip_mreqn *imr)
1720 {
1721 	int err;
1722 	__be32 addr = imr->imr_multiaddr.s_addr;
1723 	struct ip_mc_socklist *iml=NULL, *i;
1724 	struct in_device *in_dev;
1725 	struct inet_sock *inet = inet_sk(sk);
1726 	int ifindex;
1727 	int count = 0;
1728 
1729 	if (!MULTICAST(addr))
1730 		return -EINVAL;
1731 
1732 	rtnl_lock();
1733 
1734 	in_dev = ip_mc_find_dev(imr);
1735 
1736 	if (!in_dev) {
1737 		iml = NULL;
1738 		err = -ENODEV;
1739 		goto done;
1740 	}
1741 
1742 	err = -EADDRINUSE;
1743 	ifindex = imr->imr_ifindex;
1744 	for (i = inet->mc_list; i; i = i->next) {
1745 		if (i->multi.imr_multiaddr.s_addr == addr &&
1746 		    i->multi.imr_ifindex == ifindex)
1747 			goto done;
1748 		count++;
1749 	}
1750 	err = -ENOBUFS;
1751 	if (count >= sysctl_igmp_max_memberships)
1752 		goto done;
1753 	iml = sock_kmalloc(sk,sizeof(*iml),GFP_KERNEL);
1754 	if (iml == NULL)
1755 		goto done;
1756 
1757 	memcpy(&iml->multi, imr, sizeof(*imr));
1758 	iml->next = inet->mc_list;
1759 	iml->sflist = NULL;
1760 	iml->sfmode = MCAST_EXCLUDE;
1761 	inet->mc_list = iml;
1762 	ip_mc_inc_group(in_dev, addr);
1763 	err = 0;
1764 done:
1765 	rtnl_unlock();
1766 	return err;
1767 }
1768 
1769 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
1770 			   struct in_device *in_dev)
1771 {
1772 	int err;
1773 
1774 	if (iml->sflist == 0) {
1775 		/* any-source empty exclude case */
1776 		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1777 			iml->sfmode, 0, NULL, 0);
1778 	}
1779 	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1780 			iml->sfmode, iml->sflist->sl_count,
1781 			iml->sflist->sl_addr, 0);
1782 	sock_kfree_s(sk, iml->sflist, IP_SFLSIZE(iml->sflist->sl_max));
1783 	iml->sflist = NULL;
1784 	return err;
1785 }
1786 
1787 /*
1788  *	Ask a socket to leave a group.
1789  */
1790 
1791 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
1792 {
1793 	struct inet_sock *inet = inet_sk(sk);
1794 	struct ip_mc_socklist *iml, **imlp;
1795 	struct in_device *in_dev;
1796 	__be32 group = imr->imr_multiaddr.s_addr;
1797 	u32 ifindex;
1798 	int ret = -EADDRNOTAVAIL;
1799 
1800 	rtnl_lock();
1801 	in_dev = ip_mc_find_dev(imr);
1802 	ifindex = imr->imr_ifindex;
1803 	for (imlp = &inet->mc_list; (iml = *imlp) != NULL; imlp = &iml->next) {
1804 		if (iml->multi.imr_multiaddr.s_addr != group)
1805 			continue;
1806 		if (ifindex) {
1807 			if (iml->multi.imr_ifindex != ifindex)
1808 				continue;
1809 		} else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
1810 				iml->multi.imr_address.s_addr)
1811 			continue;
1812 
1813 		(void) ip_mc_leave_src(sk, iml, in_dev);
1814 
1815 		*imlp = iml->next;
1816 
1817 		if (in_dev)
1818 			ip_mc_dec_group(in_dev, group);
1819 		rtnl_unlock();
1820 		sock_kfree_s(sk, iml, sizeof(*iml));
1821 		return 0;
1822 	}
1823 	if (!in_dev)
1824 		ret = -ENODEV;
1825 	rtnl_unlock();
1826 	return ret;
1827 }
1828 
1829 int ip_mc_source(int add, int omode, struct sock *sk, struct
1830 	ip_mreq_source *mreqs, int ifindex)
1831 {
1832 	int err;
1833 	struct ip_mreqn imr;
1834 	__be32 addr = mreqs->imr_multiaddr;
1835 	struct ip_mc_socklist *pmc;
1836 	struct in_device *in_dev = NULL;
1837 	struct inet_sock *inet = inet_sk(sk);
1838 	struct ip_sf_socklist *psl;
1839 	int leavegroup = 0;
1840 	int i, j, rv;
1841 
1842 	if (!MULTICAST(addr))
1843 		return -EINVAL;
1844 
1845 	rtnl_lock();
1846 
1847 	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
1848 	imr.imr_address.s_addr = mreqs->imr_interface;
1849 	imr.imr_ifindex = ifindex;
1850 	in_dev = ip_mc_find_dev(&imr);
1851 
1852 	if (!in_dev) {
1853 		err = -ENODEV;
1854 		goto done;
1855 	}
1856 	err = -EADDRNOTAVAIL;
1857 
1858 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
1859 		if (pmc->multi.imr_multiaddr.s_addr == imr.imr_multiaddr.s_addr
1860 		    && pmc->multi.imr_ifindex == imr.imr_ifindex)
1861 			break;
1862 	}
1863 	if (!pmc) {		/* must have a prior join */
1864 		err = -EINVAL;
1865 		goto done;
1866 	}
1867 	/* if a source filter was set, must be the same mode as before */
1868 	if (pmc->sflist) {
1869 		if (pmc->sfmode != omode) {
1870 			err = -EINVAL;
1871 			goto done;
1872 		}
1873 	} else if (pmc->sfmode != omode) {
1874 		/* allow mode switches for empty-set filters */
1875 		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
1876 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
1877 			NULL, 0);
1878 		pmc->sfmode = omode;
1879 	}
1880 
1881 	psl = pmc->sflist;
1882 	if (!add) {
1883 		if (!psl)
1884 			goto done;	/* err = -EADDRNOTAVAIL */
1885 		rv = !0;
1886 		for (i=0; i<psl->sl_count; i++) {
1887 			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1888 				sizeof(__be32));
1889 			if (rv == 0)
1890 				break;
1891 		}
1892 		if (rv)		/* source not found */
1893 			goto done;	/* err = -EADDRNOTAVAIL */
1894 
1895 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
1896 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
1897 			leavegroup = 1;
1898 			goto done;
1899 		}
1900 
1901 		/* update the interface filter */
1902 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1903 			&mreqs->imr_sourceaddr, 1);
1904 
1905 		for (j=i+1; j<psl->sl_count; j++)
1906 			psl->sl_addr[j-1] = psl->sl_addr[j];
1907 		psl->sl_count--;
1908 		err = 0;
1909 		goto done;
1910 	}
1911 	/* else, add a new source to the filter */
1912 
1913 	if (psl && psl->sl_count >= sysctl_igmp_max_msf) {
1914 		err = -ENOBUFS;
1915 		goto done;
1916 	}
1917 	if (!psl || psl->sl_count == psl->sl_max) {
1918 		struct ip_sf_socklist *newpsl;
1919 		int count = IP_SFBLOCK;
1920 
1921 		if (psl)
1922 			count += psl->sl_max;
1923 		newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
1924 		if (!newpsl) {
1925 			err = -ENOBUFS;
1926 			goto done;
1927 		}
1928 		newpsl->sl_max = count;
1929 		newpsl->sl_count = count - IP_SFBLOCK;
1930 		if (psl) {
1931 			for (i=0; i<psl->sl_count; i++)
1932 				newpsl->sl_addr[i] = psl->sl_addr[i];
1933 			sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
1934 		}
1935 		pmc->sflist = psl = newpsl;
1936 	}
1937 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
1938 	for (i=0; i<psl->sl_count; i++) {
1939 		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1940 			sizeof(__be32));
1941 		if (rv == 0)
1942 			break;
1943 	}
1944 	if (rv == 0)		/* address already there is an error */
1945 		goto done;
1946 	for (j=psl->sl_count-1; j>=i; j--)
1947 		psl->sl_addr[j+1] = psl->sl_addr[j];
1948 	psl->sl_addr[i] = mreqs->imr_sourceaddr;
1949 	psl->sl_count++;
1950 	err = 0;
1951 	/* update the interface list */
1952 	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1953 		&mreqs->imr_sourceaddr, 1);
1954 done:
1955 	rtnl_unlock();
1956 	if (leavegroup)
1957 		return ip_mc_leave_group(sk, &imr);
1958 	return err;
1959 }
1960 
1961 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
1962 {
1963 	int err = 0;
1964 	struct ip_mreqn	imr;
1965 	__be32 addr = msf->imsf_multiaddr;
1966 	struct ip_mc_socklist *pmc;
1967 	struct in_device *in_dev;
1968 	struct inet_sock *inet = inet_sk(sk);
1969 	struct ip_sf_socklist *newpsl, *psl;
1970 	int leavegroup = 0;
1971 
1972 	if (!MULTICAST(addr))
1973 		return -EINVAL;
1974 	if (msf->imsf_fmode != MCAST_INCLUDE &&
1975 	    msf->imsf_fmode != MCAST_EXCLUDE)
1976 		return -EINVAL;
1977 
1978 	rtnl_lock();
1979 
1980 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
1981 	imr.imr_address.s_addr = msf->imsf_interface;
1982 	imr.imr_ifindex = ifindex;
1983 	in_dev = ip_mc_find_dev(&imr);
1984 
1985 	if (!in_dev) {
1986 		err = -ENODEV;
1987 		goto done;
1988 	}
1989 
1990 	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
1991 	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
1992 		leavegroup = 1;
1993 		goto done;
1994 	}
1995 
1996 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
1997 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
1998 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
1999 			break;
2000 	}
2001 	if (!pmc) {		/* must have a prior join */
2002 		err = -EINVAL;
2003 		goto done;
2004 	}
2005 	if (msf->imsf_numsrc) {
2006 		newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2007 							   GFP_KERNEL);
2008 		if (!newpsl) {
2009 			err = -ENOBUFS;
2010 			goto done;
2011 		}
2012 		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2013 		memcpy(newpsl->sl_addr, msf->imsf_slist,
2014 			msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2015 		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2016 			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2017 		if (err) {
2018 			sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2019 			goto done;
2020 		}
2021 	} else {
2022 		newpsl = NULL;
2023 		(void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2024 				     msf->imsf_fmode, 0, NULL, 0);
2025 	}
2026 	psl = pmc->sflist;
2027 	if (psl) {
2028 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2029 			psl->sl_count, psl->sl_addr, 0);
2030 		sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
2031 	} else
2032 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2033 			0, NULL, 0);
2034 	pmc->sflist = newpsl;
2035 	pmc->sfmode = msf->imsf_fmode;
2036 	err = 0;
2037 done:
2038 	rtnl_unlock();
2039 	if (leavegroup)
2040 		err = ip_mc_leave_group(sk, &imr);
2041 	return err;
2042 }
2043 
2044 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2045 	struct ip_msfilter __user *optval, int __user *optlen)
2046 {
2047 	int err, len, count, copycount;
2048 	struct ip_mreqn	imr;
2049 	__be32 addr = msf->imsf_multiaddr;
2050 	struct ip_mc_socklist *pmc;
2051 	struct in_device *in_dev;
2052 	struct inet_sock *inet = inet_sk(sk);
2053 	struct ip_sf_socklist *psl;
2054 
2055 	if (!MULTICAST(addr))
2056 		return -EINVAL;
2057 
2058 	rtnl_lock();
2059 
2060 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2061 	imr.imr_address.s_addr = msf->imsf_interface;
2062 	imr.imr_ifindex = 0;
2063 	in_dev = ip_mc_find_dev(&imr);
2064 
2065 	if (!in_dev) {
2066 		err = -ENODEV;
2067 		goto done;
2068 	}
2069 	err = -EADDRNOTAVAIL;
2070 
2071 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2072 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2073 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2074 			break;
2075 	}
2076 	if (!pmc)		/* must have a prior join */
2077 		goto done;
2078 	msf->imsf_fmode = pmc->sfmode;
2079 	psl = pmc->sflist;
2080 	rtnl_unlock();
2081 	if (!psl) {
2082 		len = 0;
2083 		count = 0;
2084 	} else {
2085 		count = psl->sl_count;
2086 	}
2087 	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2088 	len = copycount * sizeof(psl->sl_addr[0]);
2089 	msf->imsf_numsrc = count;
2090 	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2091 	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2092 		return -EFAULT;
2093 	}
2094 	if (len &&
2095 	    copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2096 		return -EFAULT;
2097 	return 0;
2098 done:
2099 	rtnl_unlock();
2100 	return err;
2101 }
2102 
2103 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2104 	struct group_filter __user *optval, int __user *optlen)
2105 {
2106 	int err, i, count, copycount;
2107 	struct sockaddr_in *psin;
2108 	__be32 addr;
2109 	struct ip_mc_socklist *pmc;
2110 	struct inet_sock *inet = inet_sk(sk);
2111 	struct ip_sf_socklist *psl;
2112 
2113 	psin = (struct sockaddr_in *)&gsf->gf_group;
2114 	if (psin->sin_family != AF_INET)
2115 		return -EINVAL;
2116 	addr = psin->sin_addr.s_addr;
2117 	if (!MULTICAST(addr))
2118 		return -EINVAL;
2119 
2120 	rtnl_lock();
2121 
2122 	err = -EADDRNOTAVAIL;
2123 
2124 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2125 		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2126 		    pmc->multi.imr_ifindex == gsf->gf_interface)
2127 			break;
2128 	}
2129 	if (!pmc)		/* must have a prior join */
2130 		goto done;
2131 	gsf->gf_fmode = pmc->sfmode;
2132 	psl = pmc->sflist;
2133 	rtnl_unlock();
2134 	count = psl ? psl->sl_count : 0;
2135 	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2136 	gsf->gf_numsrc = count;
2137 	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2138 	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2139 		return -EFAULT;
2140 	}
2141 	for (i=0; i<copycount; i++) {
2142 		struct sockaddr_in *psin;
2143 		struct sockaddr_storage ss;
2144 
2145 		psin = (struct sockaddr_in *)&ss;
2146 		memset(&ss, 0, sizeof(ss));
2147 		psin->sin_family = AF_INET;
2148 		psin->sin_addr.s_addr = psl->sl_addr[i];
2149 		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2150 			return -EFAULT;
2151 	}
2152 	return 0;
2153 done:
2154 	rtnl_unlock();
2155 	return err;
2156 }
2157 
2158 /*
2159  * check if a multicast source filter allows delivery for a given <src,dst,intf>
2160  */
2161 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif)
2162 {
2163 	struct inet_sock *inet = inet_sk(sk);
2164 	struct ip_mc_socklist *pmc;
2165 	struct ip_sf_socklist *psl;
2166 	int i;
2167 
2168 	if (!MULTICAST(loc_addr))
2169 		return 1;
2170 
2171 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2172 		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2173 		    pmc->multi.imr_ifindex == dif)
2174 			break;
2175 	}
2176 	if (!pmc)
2177 		return 1;
2178 	psl = pmc->sflist;
2179 	if (!psl)
2180 		return pmc->sfmode == MCAST_EXCLUDE;
2181 
2182 	for (i=0; i<psl->sl_count; i++) {
2183 		if (psl->sl_addr[i] == rmt_addr)
2184 			break;
2185 	}
2186 	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2187 		return 0;
2188 	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2189 		return 0;
2190 	return 1;
2191 }
2192 
2193 /*
2194  *	A socket is closing.
2195  */
2196 
2197 void ip_mc_drop_socket(struct sock *sk)
2198 {
2199 	struct inet_sock *inet = inet_sk(sk);
2200 	struct ip_mc_socklist *iml;
2201 
2202 	if (inet->mc_list == NULL)
2203 		return;
2204 
2205 	rtnl_lock();
2206 	while ((iml = inet->mc_list) != NULL) {
2207 		struct in_device *in_dev;
2208 		inet->mc_list = iml->next;
2209 
2210 		in_dev = inetdev_by_index(iml->multi.imr_ifindex);
2211 		(void) ip_mc_leave_src(sk, iml, in_dev);
2212 		if (in_dev != NULL) {
2213 			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2214 			in_dev_put(in_dev);
2215 		}
2216 		sock_kfree_s(sk, iml, sizeof(*iml));
2217 	}
2218 	rtnl_unlock();
2219 }
2220 
2221 int ip_check_mc(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u16 proto)
2222 {
2223 	struct ip_mc_list *im;
2224 	struct ip_sf_list *psf;
2225 	int rv = 0;
2226 
2227 	read_lock(&in_dev->mc_list_lock);
2228 	for (im=in_dev->mc_list; im; im=im->next) {
2229 		if (im->multiaddr == mc_addr)
2230 			break;
2231 	}
2232 	if (im && proto == IPPROTO_IGMP) {
2233 		rv = 1;
2234 	} else if (im) {
2235 		if (src_addr) {
2236 			for (psf=im->sources; psf; psf=psf->sf_next) {
2237 				if (psf->sf_inaddr == src_addr)
2238 					break;
2239 			}
2240 			if (psf)
2241 				rv = psf->sf_count[MCAST_INCLUDE] ||
2242 					psf->sf_count[MCAST_EXCLUDE] !=
2243 					im->sfcount[MCAST_EXCLUDE];
2244 			else
2245 				rv = im->sfcount[MCAST_EXCLUDE] != 0;
2246 		} else
2247 			rv = 1; /* unspecified source; tentatively allow */
2248 	}
2249 	read_unlock(&in_dev->mc_list_lock);
2250 	return rv;
2251 }
2252 
2253 #if defined(CONFIG_PROC_FS)
2254 struct igmp_mc_iter_state {
2255 	struct net_device *dev;
2256 	struct in_device *in_dev;
2257 };
2258 
2259 #define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2260 
2261 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2262 {
2263 	struct ip_mc_list *im = NULL;
2264 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2265 
2266 	for (state->dev = dev_base, state->in_dev = NULL;
2267 	     state->dev;
2268 	     state->dev = state->dev->next) {
2269 		struct in_device *in_dev;
2270 		in_dev = in_dev_get(state->dev);
2271 		if (!in_dev)
2272 			continue;
2273 		read_lock(&in_dev->mc_list_lock);
2274 		im = in_dev->mc_list;
2275 		if (im) {
2276 			state->in_dev = in_dev;
2277 			break;
2278 		}
2279 		read_unlock(&in_dev->mc_list_lock);
2280 		in_dev_put(in_dev);
2281 	}
2282 	return im;
2283 }
2284 
2285 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2286 {
2287 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2288 	im = im->next;
2289 	while (!im) {
2290 		if (likely(state->in_dev != NULL)) {
2291 			read_unlock(&state->in_dev->mc_list_lock);
2292 			in_dev_put(state->in_dev);
2293 		}
2294 		state->dev = state->dev->next;
2295 		if (!state->dev) {
2296 			state->in_dev = NULL;
2297 			break;
2298 		}
2299 		state->in_dev = in_dev_get(state->dev);
2300 		if (!state->in_dev)
2301 			continue;
2302 		read_lock(&state->in_dev->mc_list_lock);
2303 		im = state->in_dev->mc_list;
2304 	}
2305 	return im;
2306 }
2307 
2308 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2309 {
2310 	struct ip_mc_list *im = igmp_mc_get_first(seq);
2311 	if (im)
2312 		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2313 			--pos;
2314 	return pos ? NULL : im;
2315 }
2316 
2317 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2318 {
2319 	read_lock(&dev_base_lock);
2320 	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2321 }
2322 
2323 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2324 {
2325 	struct ip_mc_list *im;
2326 	if (v == SEQ_START_TOKEN)
2327 		im = igmp_mc_get_first(seq);
2328 	else
2329 		im = igmp_mc_get_next(seq, v);
2330 	++*pos;
2331 	return im;
2332 }
2333 
2334 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2335 {
2336 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2337 	if (likely(state->in_dev != NULL)) {
2338 		read_unlock(&state->in_dev->mc_list_lock);
2339 		in_dev_put(state->in_dev);
2340 		state->in_dev = NULL;
2341 	}
2342 	state->dev = NULL;
2343 	read_unlock(&dev_base_lock);
2344 }
2345 
2346 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2347 {
2348 	if (v == SEQ_START_TOKEN)
2349 		seq_puts(seq,
2350 			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2351 	else {
2352 		struct ip_mc_list *im = (struct ip_mc_list *)v;
2353 		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2354 		char   *querier;
2355 #ifdef CONFIG_IP_MULTICAST
2356 		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2357 			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2358 			  "V3";
2359 #else
2360 		querier = "NONE";
2361 #endif
2362 
2363 		if (state->in_dev->mc_list == im) {
2364 			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2365 				   state->dev->ifindex, state->dev->name, state->dev->mc_count, querier);
2366 		}
2367 
2368 		seq_printf(seq,
2369 			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2370 			   im->multiaddr, im->users,
2371 			   im->tm_running, im->tm_running ?
2372 			   jiffies_to_clock_t(im->timer.expires-jiffies) : 0,
2373 			   im->reporter);
2374 	}
2375 	return 0;
2376 }
2377 
2378 static struct seq_operations igmp_mc_seq_ops = {
2379 	.start	=	igmp_mc_seq_start,
2380 	.next	=	igmp_mc_seq_next,
2381 	.stop	=	igmp_mc_seq_stop,
2382 	.show	=	igmp_mc_seq_show,
2383 };
2384 
2385 static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2386 {
2387 	struct seq_file *seq;
2388 	int rc = -ENOMEM;
2389 	struct igmp_mc_iter_state *s = kzalloc(sizeof(*s), GFP_KERNEL);
2390 
2391 	if (!s)
2392 		goto out;
2393 	rc = seq_open(file, &igmp_mc_seq_ops);
2394 	if (rc)
2395 		goto out_kfree;
2396 
2397 	seq = file->private_data;
2398 	seq->private = s;
2399 out:
2400 	return rc;
2401 out_kfree:
2402 	kfree(s);
2403 	goto out;
2404 }
2405 
2406 static const struct file_operations igmp_mc_seq_fops = {
2407 	.owner		=	THIS_MODULE,
2408 	.open		=	igmp_mc_seq_open,
2409 	.read		=	seq_read,
2410 	.llseek		=	seq_lseek,
2411 	.release	=	seq_release_private,
2412 };
2413 
2414 struct igmp_mcf_iter_state {
2415 	struct net_device *dev;
2416 	struct in_device *idev;
2417 	struct ip_mc_list *im;
2418 };
2419 
2420 #define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2421 
2422 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2423 {
2424 	struct ip_sf_list *psf = NULL;
2425 	struct ip_mc_list *im = NULL;
2426 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2427 
2428 	for (state->dev = dev_base, state->idev = NULL, state->im = NULL;
2429 	     state->dev;
2430 	     state->dev = state->dev->next) {
2431 		struct in_device *idev;
2432 		idev = in_dev_get(state->dev);
2433 		if (unlikely(idev == NULL))
2434 			continue;
2435 		read_lock(&idev->mc_list_lock);
2436 		im = idev->mc_list;
2437 		if (likely(im != NULL)) {
2438 			spin_lock_bh(&im->lock);
2439 			psf = im->sources;
2440 			if (likely(psf != NULL)) {
2441 				state->im = im;
2442 				state->idev = idev;
2443 				break;
2444 			}
2445 			spin_unlock_bh(&im->lock);
2446 		}
2447 		read_unlock(&idev->mc_list_lock);
2448 		in_dev_put(idev);
2449 	}
2450 	return psf;
2451 }
2452 
2453 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2454 {
2455 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2456 
2457 	psf = psf->sf_next;
2458 	while (!psf) {
2459 		spin_unlock_bh(&state->im->lock);
2460 		state->im = state->im->next;
2461 		while (!state->im) {
2462 			if (likely(state->idev != NULL)) {
2463 				read_unlock(&state->idev->mc_list_lock);
2464 				in_dev_put(state->idev);
2465 			}
2466 			state->dev = state->dev->next;
2467 			if (!state->dev) {
2468 				state->idev = NULL;
2469 				goto out;
2470 			}
2471 			state->idev = in_dev_get(state->dev);
2472 			if (!state->idev)
2473 				continue;
2474 			read_lock(&state->idev->mc_list_lock);
2475 			state->im = state->idev->mc_list;
2476 		}
2477 		if (!state->im)
2478 			break;
2479 		spin_lock_bh(&state->im->lock);
2480 		psf = state->im->sources;
2481 	}
2482 out:
2483 	return psf;
2484 }
2485 
2486 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2487 {
2488 	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2489 	if (psf)
2490 		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2491 			--pos;
2492 	return pos ? NULL : psf;
2493 }
2494 
2495 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2496 {
2497 	read_lock(&dev_base_lock);
2498 	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2499 }
2500 
2501 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2502 {
2503 	struct ip_sf_list *psf;
2504 	if (v == SEQ_START_TOKEN)
2505 		psf = igmp_mcf_get_first(seq);
2506 	else
2507 		psf = igmp_mcf_get_next(seq, v);
2508 	++*pos;
2509 	return psf;
2510 }
2511 
2512 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2513 {
2514 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2515 	if (likely(state->im != NULL)) {
2516 		spin_unlock_bh(&state->im->lock);
2517 		state->im = NULL;
2518 	}
2519 	if (likely(state->idev != NULL)) {
2520 		read_unlock(&state->idev->mc_list_lock);
2521 		in_dev_put(state->idev);
2522 		state->idev = NULL;
2523 	}
2524 	state->dev = NULL;
2525 	read_unlock(&dev_base_lock);
2526 }
2527 
2528 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2529 {
2530 	struct ip_sf_list *psf = (struct ip_sf_list *)v;
2531 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2532 
2533 	if (v == SEQ_START_TOKEN) {
2534 		seq_printf(seq,
2535 			   "%3s %6s "
2536 			   "%10s %10s %6s %6s\n", "Idx",
2537 			   "Device", "MCA",
2538 			   "SRC", "INC", "EXC");
2539 	} else {
2540 		seq_printf(seq,
2541 			   "%3d %6.6s 0x%08x "
2542 			   "0x%08x %6lu %6lu\n",
2543 			   state->dev->ifindex, state->dev->name,
2544 			   ntohl(state->im->multiaddr),
2545 			   ntohl(psf->sf_inaddr),
2546 			   psf->sf_count[MCAST_INCLUDE],
2547 			   psf->sf_count[MCAST_EXCLUDE]);
2548 	}
2549 	return 0;
2550 }
2551 
2552 static struct seq_operations igmp_mcf_seq_ops = {
2553 	.start	=	igmp_mcf_seq_start,
2554 	.next	=	igmp_mcf_seq_next,
2555 	.stop	=	igmp_mcf_seq_stop,
2556 	.show	=	igmp_mcf_seq_show,
2557 };
2558 
2559 static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2560 {
2561 	struct seq_file *seq;
2562 	int rc = -ENOMEM;
2563 	struct igmp_mcf_iter_state *s = kzalloc(sizeof(*s), GFP_KERNEL);
2564 
2565 	if (!s)
2566 		goto out;
2567 	rc = seq_open(file, &igmp_mcf_seq_ops);
2568 	if (rc)
2569 		goto out_kfree;
2570 
2571 	seq = file->private_data;
2572 	seq->private = s;
2573 out:
2574 	return rc;
2575 out_kfree:
2576 	kfree(s);
2577 	goto out;
2578 }
2579 
2580 static const struct file_operations igmp_mcf_seq_fops = {
2581 	.owner		=	THIS_MODULE,
2582 	.open		=	igmp_mcf_seq_open,
2583 	.read		=	seq_read,
2584 	.llseek		=	seq_lseek,
2585 	.release	=	seq_release_private,
2586 };
2587 
2588 int __init igmp_mc_proc_init(void)
2589 {
2590 	proc_net_fops_create("igmp", S_IRUGO, &igmp_mc_seq_fops);
2591 	proc_net_fops_create("mcfilter", S_IRUGO, &igmp_mcf_seq_fops);
2592 	return 0;
2593 }
2594 #endif
2595 
2596 EXPORT_SYMBOL(ip_mc_dec_group);
2597 EXPORT_SYMBOL(ip_mc_inc_group);
2598 EXPORT_SYMBOL(ip_mc_join_group);
2599