xref: /openbmc/linux/net/ipv4/igmp.c (revision 4e0c1159d83a658d1ffba5bc3442f4ec4cadb436)
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/config.h>
76 #include <linux/module.h>
77 #include <asm/uaccess.h>
78 #include <asm/system.h>
79 #include <linux/types.h>
80 #include <linux/kernel.h>
81 #include <linux/jiffies.h>
82 #include <linux/string.h>
83 #include <linux/socket.h>
84 #include <linux/sockios.h>
85 #include <linux/in.h>
86 #include <linux/inet.h>
87 #include <linux/netdevice.h>
88 #include <linux/skbuff.h>
89 #include <linux/inetdevice.h>
90 #include <linux/igmp.h>
91 #include <linux/if_arp.h>
92 #include <linux/rtnetlink.h>
93 #include <linux/times.h>
94 #include <net/ip.h>
95 #include <net/protocol.h>
96 #include <net/route.h>
97 #include <net/sock.h>
98 #include <net/checksum.h>
99 #include <linux/netfilter_ipv4.h>
100 #ifdef CONFIG_IP_MROUTE
101 #include <linux/mroute.h>
102 #endif
103 #ifdef CONFIG_PROC_FS
104 #include <linux/proc_fs.h>
105 #include <linux/seq_file.h>
106 #endif
107 
108 #define IP_MAX_MEMBERSHIPS	20
109 #define IP_MAX_MSF		10
110 
111 #ifdef CONFIG_IP_MULTICAST
112 /* Parameter names and values are taken from igmp-v2-06 draft */
113 
114 #define IGMP_V1_Router_Present_Timeout		(400*HZ)
115 #define IGMP_V2_Router_Present_Timeout		(400*HZ)
116 #define IGMP_Unsolicited_Report_Interval	(10*HZ)
117 #define IGMP_Query_Response_Interval		(10*HZ)
118 #define IGMP_Unsolicited_Report_Count		2
119 
120 
121 #define IGMP_Initial_Report_Delay		(1)
122 
123 /* IGMP_Initial_Report_Delay is not from IGMP specs!
124  * IGMP specs require to report membership immediately after
125  * joining a group, but we delay the first report by a
126  * small interval. It seems more natural and still does not
127  * contradict to specs provided this delay is small enough.
128  */
129 
130 #define IGMP_V1_SEEN(in_dev) (ipv4_devconf.force_igmp_version == 1 || \
131 		(in_dev)->cnf.force_igmp_version == 1 || \
132 		((in_dev)->mr_v1_seen && \
133 		time_before(jiffies, (in_dev)->mr_v1_seen)))
134 #define IGMP_V2_SEEN(in_dev) (ipv4_devconf.force_igmp_version == 2 || \
135 		(in_dev)->cnf.force_igmp_version == 2 || \
136 		((in_dev)->mr_v2_seen && \
137 		time_before(jiffies, (in_dev)->mr_v2_seen)))
138 
139 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im);
140 static void igmpv3_del_delrec(struct in_device *in_dev, __u32 multiaddr);
141 static void igmpv3_clear_delrec(struct in_device *in_dev);
142 static int sf_setstate(struct ip_mc_list *pmc);
143 static void sf_markstate(struct ip_mc_list *pmc);
144 #endif
145 static void ip_mc_clear_src(struct ip_mc_list *pmc);
146 static int ip_mc_add_src(struct in_device *in_dev, __u32 *pmca, int sfmode,
147 			 int sfcount, __u32 *psfsrc, int delta);
148 
149 static void ip_ma_put(struct ip_mc_list *im)
150 {
151 	if (atomic_dec_and_test(&im->refcnt)) {
152 		in_dev_put(im->interface);
153 		kfree(im);
154 	}
155 }
156 
157 #ifdef CONFIG_IP_MULTICAST
158 
159 /*
160  *	Timer management
161  */
162 
163 static __inline__ void igmp_stop_timer(struct ip_mc_list *im)
164 {
165 	spin_lock_bh(&im->lock);
166 	if (del_timer(&im->timer))
167 		atomic_dec(&im->refcnt);
168 	im->tm_running=0;
169 	im->reporter = 0;
170 	im->unsolicit_count = 0;
171 	spin_unlock_bh(&im->lock);
172 }
173 
174 /* It must be called with locked im->lock */
175 static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
176 {
177 	int tv=net_random() % max_delay;
178 
179 	im->tm_running=1;
180 	if (!mod_timer(&im->timer, jiffies+tv+2))
181 		atomic_inc(&im->refcnt);
182 }
183 
184 static void igmp_gq_start_timer(struct in_device *in_dev)
185 {
186 	int tv = net_random() % in_dev->mr_maxdelay;
187 
188 	in_dev->mr_gq_running = 1;
189 	if (!mod_timer(&in_dev->mr_gq_timer, jiffies+tv+2))
190 		in_dev_hold(in_dev);
191 }
192 
193 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
194 {
195 	int tv = net_random() % delay;
196 
197 	if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
198 		in_dev_hold(in_dev);
199 }
200 
201 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
202 {
203 	spin_lock_bh(&im->lock);
204 	im->unsolicit_count = 0;
205 	if (del_timer(&im->timer)) {
206 		if ((long)(im->timer.expires-jiffies) < max_delay) {
207 			add_timer(&im->timer);
208 			im->tm_running=1;
209 			spin_unlock_bh(&im->lock);
210 			return;
211 		}
212 		atomic_dec(&im->refcnt);
213 	}
214 	igmp_start_timer(im, max_delay);
215 	spin_unlock_bh(&im->lock);
216 }
217 
218 
219 /*
220  *	Send an IGMP report.
221  */
222 
223 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
224 
225 
226 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
227 	int gdeleted, int sdeleted)
228 {
229 	switch (type) {
230 	case IGMPV3_MODE_IS_INCLUDE:
231 	case IGMPV3_MODE_IS_EXCLUDE:
232 		if (gdeleted || sdeleted)
233 			return 0;
234 		return !(pmc->gsquery && !psf->sf_gsresp);
235 	case IGMPV3_CHANGE_TO_INCLUDE:
236 		if (gdeleted || sdeleted)
237 			return 0;
238 		return psf->sf_count[MCAST_INCLUDE] != 0;
239 	case IGMPV3_CHANGE_TO_EXCLUDE:
240 		if (gdeleted || sdeleted)
241 			return 0;
242 		if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
243 		    psf->sf_count[MCAST_INCLUDE])
244 			return 0;
245 		return pmc->sfcount[MCAST_EXCLUDE] ==
246 			psf->sf_count[MCAST_EXCLUDE];
247 	case IGMPV3_ALLOW_NEW_SOURCES:
248 		if (gdeleted || !psf->sf_crcount)
249 			return 0;
250 		return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
251 	case IGMPV3_BLOCK_OLD_SOURCES:
252 		if (pmc->sfmode == MCAST_INCLUDE)
253 			return gdeleted || (psf->sf_crcount && sdeleted);
254 		return psf->sf_crcount && !gdeleted && !sdeleted;
255 	}
256 	return 0;
257 }
258 
259 static int
260 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
261 {
262 	struct ip_sf_list *psf;
263 	int scount = 0;
264 
265 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
266 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
267 			continue;
268 		scount++;
269 	}
270 	return scount;
271 }
272 
273 static struct sk_buff *igmpv3_newpack(struct net_device *dev, int size)
274 {
275 	struct sk_buff *skb;
276 	struct rtable *rt;
277 	struct iphdr *pip;
278 	struct igmpv3_report *pig;
279 
280 	skb = alloc_skb(size + LL_RESERVED_SPACE(dev), GFP_ATOMIC);
281 	if (skb == NULL)
282 		return NULL;
283 
284 	{
285 		struct flowi fl = { .oif = dev->ifindex,
286 				    .nl_u = { .ip4_u = {
287 				    .daddr = IGMPV3_ALL_MCR } },
288 				    .proto = IPPROTO_IGMP };
289 		if (ip_route_output_key(&rt, &fl)) {
290 			kfree_skb(skb);
291 			return NULL;
292 		}
293 	}
294 	if (rt->rt_src == 0) {
295 		kfree_skb(skb);
296 		ip_rt_put(rt);
297 		return NULL;
298 	}
299 
300 	skb->dst = &rt->u.dst;
301 	skb->dev = dev;
302 
303 	skb_reserve(skb, LL_RESERVED_SPACE(dev));
304 
305 	skb->nh.iph = pip =(struct iphdr *)skb_put(skb, sizeof(struct iphdr)+4);
306 
307 	pip->version  = 4;
308 	pip->ihl      = (sizeof(struct iphdr)+4)>>2;
309 	pip->tos      = 0xc0;
310 	pip->frag_off = htons(IP_DF);
311 	pip->ttl      = 1;
312 	pip->daddr    = rt->rt_dst;
313 	pip->saddr    = rt->rt_src;
314 	pip->protocol = IPPROTO_IGMP;
315 	pip->tot_len  = 0;	/* filled in later */
316 	ip_select_ident(pip, &rt->u.dst, NULL);
317 	((u8*)&pip[1])[0] = IPOPT_RA;
318 	((u8*)&pip[1])[1] = 4;
319 	((u8*)&pip[1])[2] = 0;
320 	((u8*)&pip[1])[3] = 0;
321 
322 	pig =(struct igmpv3_report *)skb_put(skb, sizeof(*pig));
323 	skb->h.igmph = (struct igmphdr *)pig;
324 	pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
325 	pig->resv1 = 0;
326 	pig->csum = 0;
327 	pig->resv2 = 0;
328 	pig->ngrec = 0;
329 	return skb;
330 }
331 
332 static int igmpv3_sendpack(struct sk_buff *skb)
333 {
334 	struct iphdr *pip = skb->nh.iph;
335 	struct igmphdr *pig = skb->h.igmph;
336 	int iplen, igmplen;
337 
338 	iplen = skb->tail - (unsigned char *)skb->nh.iph;
339 	pip->tot_len = htons(iplen);
340 	ip_send_check(pip);
341 
342 	igmplen = skb->tail - (unsigned char *)skb->h.igmph;
343 	pig->csum = ip_compute_csum((void *)skb->h.igmph, igmplen);
344 
345 	return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, skb->dev,
346 		       dst_output);
347 }
348 
349 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
350 {
351 	return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc,type,gdel,sdel);
352 }
353 
354 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
355 	int type, struct igmpv3_grec **ppgr)
356 {
357 	struct net_device *dev = pmc->interface->dev;
358 	struct igmpv3_report *pih;
359 	struct igmpv3_grec *pgr;
360 
361 	if (!skb)
362 		skb = igmpv3_newpack(dev, dev->mtu);
363 	if (!skb)
364 		return NULL;
365 	pgr = (struct igmpv3_grec *)skb_put(skb, sizeof(struct igmpv3_grec));
366 	pgr->grec_type = type;
367 	pgr->grec_auxwords = 0;
368 	pgr->grec_nsrcs = 0;
369 	pgr->grec_mca = pmc->multiaddr;
370 	pih = (struct igmpv3_report *)skb->h.igmph;
371 	pih->ngrec = htons(ntohs(pih->ngrec)+1);
372 	*ppgr = pgr;
373 	return skb;
374 }
375 
376 #define AVAILABLE(skb) ((skb) ? ((skb)->dev ? (skb)->dev->mtu - (skb)->len : \
377 	skb_tailroom(skb)) : 0)
378 
379 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
380 	int type, int gdeleted, int sdeleted)
381 {
382 	struct net_device *dev = pmc->interface->dev;
383 	struct igmpv3_report *pih;
384 	struct igmpv3_grec *pgr = NULL;
385 	struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
386 	int scount, first, isquery, truncate;
387 
388 	if (pmc->multiaddr == IGMP_ALL_HOSTS)
389 		return skb;
390 
391 	isquery = type == IGMPV3_MODE_IS_INCLUDE ||
392 		  type == IGMPV3_MODE_IS_EXCLUDE;
393 	truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
394 		    type == IGMPV3_CHANGE_TO_EXCLUDE;
395 
396 	psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
397 
398 	if (!*psf_list) {
399 		if (type == IGMPV3_ALLOW_NEW_SOURCES ||
400 		    type == IGMPV3_BLOCK_OLD_SOURCES)
401 			return skb;
402 		if (pmc->crcount || isquery) {
403 			/* make sure we have room for group header and at
404 			 * least one source.
405 			 */
406 			if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)+
407 			    sizeof(__u32)) {
408 				igmpv3_sendpack(skb);
409 				skb = NULL; /* add_grhead will get a new one */
410 			}
411 			skb = add_grhead(skb, pmc, type, &pgr);
412 		}
413 		return skb;
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 	scount = 0;
428 	psf_prev = NULL;
429 	for (psf=*psf_list; psf; psf=psf_next) {
430 		u32 *psrc;
431 
432 		psf_next = psf->sf_next;
433 
434 		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
435 			psf_prev = psf;
436 			continue;
437 		}
438 
439 		/* clear marks on query responses */
440 		if (isquery)
441 			psf->sf_gsresp = 0;
442 
443 		if (AVAILABLE(skb) < sizeof(u32) +
444 		    first*sizeof(struct igmpv3_grec)) {
445 			if (truncate && !first)
446 				break;	 /* truncate these */
447 			if (pgr)
448 				pgr->grec_nsrcs = htons(scount);
449 			if (skb)
450 				igmpv3_sendpack(skb);
451 			skb = igmpv3_newpack(dev, dev->mtu);
452 			first = 1;
453 			scount = 0;
454 		}
455 		if (first) {
456 			skb = add_grhead(skb, pmc, type, &pgr);
457 			first = 0;
458 		}
459 		psrc = (u32 *)skb_put(skb, sizeof(u32));
460 		*psrc = psf->sf_inaddr;
461 		scount++;
462 		if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
463 		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
464 			psf->sf_crcount--;
465 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
466 				if (psf_prev)
467 					psf_prev->sf_next = psf->sf_next;
468 				else
469 					*psf_list = psf->sf_next;
470 				kfree(psf);
471 				continue;
472 			}
473 		}
474 		psf_prev = psf;
475 	}
476 	if (pgr)
477 		pgr->grec_nsrcs = htons(scount);
478 
479 	if (isquery)
480 		pmc->gsquery = 0;	/* clear query state on report */
481 	return skb;
482 }
483 
484 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
485 {
486 	struct sk_buff *skb = NULL;
487 	int type;
488 
489 	if (!pmc) {
490 		read_lock(&in_dev->mc_list_lock);
491 		for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
492 			if (pmc->multiaddr == IGMP_ALL_HOSTS)
493 				continue;
494 			spin_lock_bh(&pmc->lock);
495 			if (pmc->sfcount[MCAST_EXCLUDE])
496 				type = IGMPV3_MODE_IS_EXCLUDE;
497 			else
498 				type = IGMPV3_MODE_IS_INCLUDE;
499 			skb = add_grec(skb, pmc, type, 0, 0);
500 			spin_unlock_bh(&pmc->lock);
501 		}
502 		read_unlock(&in_dev->mc_list_lock);
503 	} else {
504 		spin_lock_bh(&pmc->lock);
505 		if (pmc->sfcount[MCAST_EXCLUDE])
506 			type = IGMPV3_MODE_IS_EXCLUDE;
507 		else
508 			type = IGMPV3_MODE_IS_INCLUDE;
509 		skb = add_grec(skb, pmc, type, 0, 0);
510 		spin_unlock_bh(&pmc->lock);
511 	}
512 	if (!skb)
513 		return 0;
514 	return igmpv3_sendpack(skb);
515 }
516 
517 /*
518  * remove zero-count source records from a source filter list
519  */
520 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
521 {
522 	struct ip_sf_list *psf_prev, *psf_next, *psf;
523 
524 	psf_prev = NULL;
525 	for (psf=*ppsf; psf; psf = psf_next) {
526 		psf_next = psf->sf_next;
527 		if (psf->sf_crcount == 0) {
528 			if (psf_prev)
529 				psf_prev->sf_next = psf->sf_next;
530 			else
531 				*ppsf = psf->sf_next;
532 			kfree(psf);
533 		} else
534 			psf_prev = psf;
535 	}
536 }
537 
538 static void igmpv3_send_cr(struct in_device *in_dev)
539 {
540 	struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
541 	struct sk_buff *skb = NULL;
542 	int type, dtype;
543 
544 	read_lock(&in_dev->mc_list_lock);
545 	spin_lock_bh(&in_dev->mc_tomb_lock);
546 
547 	/* deleted MCA's */
548 	pmc_prev = NULL;
549 	for (pmc=in_dev->mc_tomb; pmc; pmc=pmc_next) {
550 		pmc_next = pmc->next;
551 		if (pmc->sfmode == MCAST_INCLUDE) {
552 			type = IGMPV3_BLOCK_OLD_SOURCES;
553 			dtype = IGMPV3_BLOCK_OLD_SOURCES;
554 			skb = add_grec(skb, pmc, type, 1, 0);
555 			skb = add_grec(skb, pmc, dtype, 1, 1);
556 		}
557 		if (pmc->crcount) {
558 			pmc->crcount--;
559 			if (pmc->sfmode == MCAST_EXCLUDE) {
560 				type = IGMPV3_CHANGE_TO_INCLUDE;
561 				skb = add_grec(skb, pmc, type, 1, 0);
562 			}
563 			if (pmc->crcount == 0) {
564 				igmpv3_clear_zeros(&pmc->tomb);
565 				igmpv3_clear_zeros(&pmc->sources);
566 			}
567 		}
568 		if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
569 			if (pmc_prev)
570 				pmc_prev->next = pmc_next;
571 			else
572 				in_dev->mc_tomb = pmc_next;
573 			in_dev_put(pmc->interface);
574 			kfree(pmc);
575 		} else
576 			pmc_prev = pmc;
577 	}
578 	spin_unlock_bh(&in_dev->mc_tomb_lock);
579 
580 	/* change recs */
581 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
582 		spin_lock_bh(&pmc->lock);
583 		if (pmc->sfcount[MCAST_EXCLUDE]) {
584 			type = IGMPV3_BLOCK_OLD_SOURCES;
585 			dtype = IGMPV3_ALLOW_NEW_SOURCES;
586 		} else {
587 			type = IGMPV3_ALLOW_NEW_SOURCES;
588 			dtype = IGMPV3_BLOCK_OLD_SOURCES;
589 		}
590 		skb = add_grec(skb, pmc, type, 0, 0);
591 		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
592 
593 		/* filter mode changes */
594 		if (pmc->crcount) {
595 			pmc->crcount--;
596 			if (pmc->sfmode == MCAST_EXCLUDE)
597 				type = IGMPV3_CHANGE_TO_EXCLUDE;
598 			else
599 				type = IGMPV3_CHANGE_TO_INCLUDE;
600 			skb = add_grec(skb, pmc, type, 0, 0);
601 		}
602 		spin_unlock_bh(&pmc->lock);
603 	}
604 	read_unlock(&in_dev->mc_list_lock);
605 
606 	if (!skb)
607 		return;
608 	(void) igmpv3_sendpack(skb);
609 }
610 
611 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
612 	int type)
613 {
614 	struct sk_buff *skb;
615 	struct iphdr *iph;
616 	struct igmphdr *ih;
617 	struct rtable *rt;
618 	struct net_device *dev = in_dev->dev;
619 	u32	group = pmc ? pmc->multiaddr : 0;
620 	u32	dst;
621 
622 	if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
623 		return igmpv3_send_report(in_dev, pmc);
624 	else if (type == IGMP_HOST_LEAVE_MESSAGE)
625 		dst = IGMP_ALL_ROUTER;
626 	else
627 		dst = group;
628 
629 	{
630 		struct flowi fl = { .oif = dev->ifindex,
631 				    .nl_u = { .ip4_u = { .daddr = dst } },
632 				    .proto = IPPROTO_IGMP };
633 		if (ip_route_output_key(&rt, &fl))
634 			return -1;
635 	}
636 	if (rt->rt_src == 0) {
637 		ip_rt_put(rt);
638 		return -1;
639 	}
640 
641 	skb=alloc_skb(IGMP_SIZE+LL_RESERVED_SPACE(dev), GFP_ATOMIC);
642 	if (skb == NULL) {
643 		ip_rt_put(rt);
644 		return -1;
645 	}
646 
647 	skb->dst = &rt->u.dst;
648 
649 	skb_reserve(skb, LL_RESERVED_SPACE(dev));
650 
651 	skb->nh.iph = iph = (struct iphdr *)skb_put(skb, sizeof(struct iphdr)+4);
652 
653 	iph->version  = 4;
654 	iph->ihl      = (sizeof(struct iphdr)+4)>>2;
655 	iph->tos      = 0xc0;
656 	iph->frag_off = htons(IP_DF);
657 	iph->ttl      = 1;
658 	iph->daddr    = dst;
659 	iph->saddr    = rt->rt_src;
660 	iph->protocol = IPPROTO_IGMP;
661 	iph->tot_len  = htons(IGMP_SIZE);
662 	ip_select_ident(iph, &rt->u.dst, NULL);
663 	((u8*)&iph[1])[0] = IPOPT_RA;
664 	((u8*)&iph[1])[1] = 4;
665 	((u8*)&iph[1])[2] = 0;
666 	((u8*)&iph[1])[3] = 0;
667 	ip_send_check(iph);
668 
669 	ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
670 	ih->type=type;
671 	ih->code=0;
672 	ih->csum=0;
673 	ih->group=group;
674 	ih->csum=ip_compute_csum((void *)ih, sizeof(struct igmphdr));
675 
676 	return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, rt->u.dst.dev,
677 		       dst_output);
678 }
679 
680 static void igmp_gq_timer_expire(unsigned long data)
681 {
682 	struct in_device *in_dev = (struct in_device *)data;
683 
684 	in_dev->mr_gq_running = 0;
685 	igmpv3_send_report(in_dev, NULL);
686 	__in_dev_put(in_dev);
687 }
688 
689 static void igmp_ifc_timer_expire(unsigned long data)
690 {
691 	struct in_device *in_dev = (struct in_device *)data;
692 
693 	igmpv3_send_cr(in_dev);
694 	if (in_dev->mr_ifc_count) {
695 		in_dev->mr_ifc_count--;
696 		igmp_ifc_start_timer(in_dev, IGMP_Unsolicited_Report_Interval);
697 	}
698 	__in_dev_put(in_dev);
699 }
700 
701 static void igmp_ifc_event(struct in_device *in_dev)
702 {
703 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
704 		return;
705 	in_dev->mr_ifc_count = in_dev->mr_qrv ? in_dev->mr_qrv :
706 		IGMP_Unsolicited_Report_Count;
707 	igmp_ifc_start_timer(in_dev, 1);
708 }
709 
710 
711 static void igmp_timer_expire(unsigned long data)
712 {
713 	struct ip_mc_list *im=(struct ip_mc_list *)data;
714 	struct in_device *in_dev = im->interface;
715 
716 	spin_lock(&im->lock);
717 	im->tm_running=0;
718 
719 	if (im->unsolicit_count) {
720 		im->unsolicit_count--;
721 		igmp_start_timer(im, IGMP_Unsolicited_Report_Interval);
722 	}
723 	im->reporter = 1;
724 	spin_unlock(&im->lock);
725 
726 	if (IGMP_V1_SEEN(in_dev))
727 		igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
728 	else if (IGMP_V2_SEEN(in_dev))
729 		igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
730 	else
731 		igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
732 
733 	ip_ma_put(im);
734 }
735 
736 static void igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __u32 *srcs)
737 {
738 	struct ip_sf_list *psf;
739 	int i, scount;
740 
741 	scount = 0;
742 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
743 		if (scount == nsrcs)
744 			break;
745 		for (i=0; i<nsrcs; i++)
746 			if (srcs[i] == psf->sf_inaddr) {
747 				psf->sf_gsresp = 1;
748 				scount++;
749 				break;
750 			}
751 	}
752 }
753 
754 static void igmp_heard_report(struct in_device *in_dev, u32 group)
755 {
756 	struct ip_mc_list *im;
757 
758 	/* Timers are only set for non-local groups */
759 
760 	if (group == IGMP_ALL_HOSTS)
761 		return;
762 
763 	read_lock(&in_dev->mc_list_lock);
764 	for (im=in_dev->mc_list; im!=NULL; im=im->next) {
765 		if (im->multiaddr == group) {
766 			igmp_stop_timer(im);
767 			break;
768 		}
769 	}
770 	read_unlock(&in_dev->mc_list_lock);
771 }
772 
773 static void igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
774 	int len)
775 {
776 	struct igmphdr 		*ih = skb->h.igmph;
777 	struct igmpv3_query *ih3 = (struct igmpv3_query *)ih;
778 	struct ip_mc_list	*im;
779 	u32			group = ih->group;
780 	int			max_delay;
781 	int			mark = 0;
782 
783 
784 	if (len == 8) {
785 		if (ih->code == 0) {
786 			/* Alas, old v1 router presents here. */
787 
788 			max_delay = IGMP_Query_Response_Interval;
789 			in_dev->mr_v1_seen = jiffies +
790 				IGMP_V1_Router_Present_Timeout;
791 			group = 0;
792 		} else {
793 			/* v2 router present */
794 			max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
795 			in_dev->mr_v2_seen = jiffies +
796 				IGMP_V2_Router_Present_Timeout;
797 		}
798 		/* cancel the interface change timer */
799 		in_dev->mr_ifc_count = 0;
800 		if (del_timer(&in_dev->mr_ifc_timer))
801 			__in_dev_put(in_dev);
802 		/* clear deleted report items */
803 		igmpv3_clear_delrec(in_dev);
804 	} else if (len < 12) {
805 		return;	/* ignore bogus packet; freed by caller */
806 	} else { /* v3 */
807 		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
808 			return;
809 
810 		ih3 = (struct igmpv3_query *) skb->h.raw;
811 		if (ih3->nsrcs) {
812 			if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
813 					   + ntohs(ih3->nsrcs)*sizeof(__u32)))
814 				return;
815 			ih3 = (struct igmpv3_query *) skb->h.raw;
816 		}
817 
818 		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
819 		if (!max_delay)
820 			max_delay = 1;	/* can't mod w/ 0 */
821 		in_dev->mr_maxdelay = max_delay;
822 		if (ih3->qrv)
823 			in_dev->mr_qrv = ih3->qrv;
824 		if (!group) { /* general query */
825 			if (ih3->nsrcs)
826 				return;	/* no sources allowed */
827 			igmp_gq_start_timer(in_dev);
828 			return;
829 		}
830 		/* mark sources to include, if group & source-specific */
831 		mark = ih3->nsrcs != 0;
832 	}
833 
834 	/*
835 	 * - Start the timers in all of our membership records
836 	 *   that the query applies to for the interface on
837 	 *   which the query arrived excl. those that belong
838 	 *   to a "local" group (224.0.0.X)
839 	 * - For timers already running check if they need to
840 	 *   be reset.
841 	 * - Use the igmp->igmp_code field as the maximum
842 	 *   delay possible
843 	 */
844 	read_lock(&in_dev->mc_list_lock);
845 	for (im=in_dev->mc_list; im!=NULL; im=im->next) {
846 		if (group && group != im->multiaddr)
847 			continue;
848 		if (im->multiaddr == IGMP_ALL_HOSTS)
849 			continue;
850 		spin_lock_bh(&im->lock);
851 		if (im->tm_running)
852 			im->gsquery = im->gsquery && mark;
853 		else
854 			im->gsquery = mark;
855 		if (im->gsquery)
856 			igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
857 		spin_unlock_bh(&im->lock);
858 		igmp_mod_timer(im, max_delay);
859 	}
860 	read_unlock(&in_dev->mc_list_lock);
861 }
862 
863 int igmp_rcv(struct sk_buff *skb)
864 {
865 	/* This basically follows the spec line by line -- see RFC1112 */
866 	struct igmphdr *ih;
867 	struct in_device *in_dev = in_dev_get(skb->dev);
868 	int len = skb->len;
869 
870 	if (in_dev==NULL) {
871 		kfree_skb(skb);
872 		return 0;
873 	}
874 
875 	if (!pskb_may_pull(skb, sizeof(struct igmphdr)) ||
876 	    (u16)csum_fold(skb_checksum(skb, 0, len, 0))) {
877 		in_dev_put(in_dev);
878 		kfree_skb(skb);
879 		return 0;
880 	}
881 
882 	ih = skb->h.igmph;
883 	switch (ih->type) {
884 	case IGMP_HOST_MEMBERSHIP_QUERY:
885 		igmp_heard_query(in_dev, skb, len);
886 		break;
887 	case IGMP_HOST_MEMBERSHIP_REPORT:
888 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
889 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
890 		/* Is it our report looped back? */
891 		if (((struct rtable*)skb->dst)->fl.iif == 0)
892 			break;
893 		igmp_heard_report(in_dev, ih->group);
894 		break;
895 	case IGMP_PIM:
896 #ifdef CONFIG_IP_PIMSM_V1
897 		in_dev_put(in_dev);
898 		return pim_rcv_v1(skb);
899 #endif
900 	case IGMP_DVMRP:
901 	case IGMP_TRACE:
902 	case IGMP_HOST_LEAVE_MESSAGE:
903 	case IGMP_MTRACE:
904 	case IGMP_MTRACE_RESP:
905 		break;
906 	default:
907 		NETDEBUG(KERN_DEBUG "New IGMP type=%d, why we do not know about it?\n", ih->type);
908 	}
909 	in_dev_put(in_dev);
910 	kfree_skb(skb);
911 	return 0;
912 }
913 
914 #endif
915 
916 
917 /*
918  *	Add a filter to a device
919  */
920 
921 static void ip_mc_filter_add(struct in_device *in_dev, u32 addr)
922 {
923 	char buf[MAX_ADDR_LEN];
924 	struct net_device *dev = in_dev->dev;
925 
926 	/* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
927 	   We will get multicast token leakage, when IFF_MULTICAST
928 	   is changed. This check should be done in dev->set_multicast_list
929 	   routine. Something sort of:
930 	   if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
931 	   --ANK
932 	   */
933 	if (arp_mc_map(addr, buf, dev, 0) == 0)
934 		dev_mc_add(dev,buf,dev->addr_len,0);
935 }
936 
937 /*
938  *	Remove a filter from a device
939  */
940 
941 static void ip_mc_filter_del(struct in_device *in_dev, u32 addr)
942 {
943 	char buf[MAX_ADDR_LEN];
944 	struct net_device *dev = in_dev->dev;
945 
946 	if (arp_mc_map(addr, buf, dev, 0) == 0)
947 		dev_mc_delete(dev,buf,dev->addr_len,0);
948 }
949 
950 #ifdef CONFIG_IP_MULTICAST
951 /*
952  * deleted ip_mc_list manipulation
953  */
954 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
955 {
956 	struct ip_mc_list *pmc;
957 
958 	/* this is an "ip_mc_list" for convenience; only the fields below
959 	 * are actually used. In particular, the refcnt and users are not
960 	 * used for management of the delete list. Using the same structure
961 	 * for deleted items allows change reports to use common code with
962 	 * non-deleted or query-response MCA's.
963 	 */
964 	pmc = (struct ip_mc_list *)kmalloc(sizeof(*pmc), GFP_KERNEL);
965 	if (!pmc)
966 		return;
967 	memset(pmc, 0, sizeof(*pmc));
968 	spin_lock_bh(&im->lock);
969 	pmc->interface = im->interface;
970 	in_dev_hold(in_dev);
971 	pmc->multiaddr = im->multiaddr;
972 	pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
973 		IGMP_Unsolicited_Report_Count;
974 	pmc->sfmode = im->sfmode;
975 	if (pmc->sfmode == MCAST_INCLUDE) {
976 		struct ip_sf_list *psf;
977 
978 		pmc->tomb = im->tomb;
979 		pmc->sources = im->sources;
980 		im->tomb = im->sources = NULL;
981 		for (psf=pmc->sources; psf; psf=psf->sf_next)
982 			psf->sf_crcount = pmc->crcount;
983 	}
984 	spin_unlock_bh(&im->lock);
985 
986 	spin_lock_bh(&in_dev->mc_tomb_lock);
987 	pmc->next = in_dev->mc_tomb;
988 	in_dev->mc_tomb = pmc;
989 	spin_unlock_bh(&in_dev->mc_tomb_lock);
990 }
991 
992 static void igmpv3_del_delrec(struct in_device *in_dev, __u32 multiaddr)
993 {
994 	struct ip_mc_list *pmc, *pmc_prev;
995 	struct ip_sf_list *psf, *psf_next;
996 
997 	spin_lock_bh(&in_dev->mc_tomb_lock);
998 	pmc_prev = NULL;
999 	for (pmc=in_dev->mc_tomb; pmc; pmc=pmc->next) {
1000 		if (pmc->multiaddr == multiaddr)
1001 			break;
1002 		pmc_prev = pmc;
1003 	}
1004 	if (pmc) {
1005 		if (pmc_prev)
1006 			pmc_prev->next = pmc->next;
1007 		else
1008 			in_dev->mc_tomb = pmc->next;
1009 	}
1010 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1011 	if (pmc) {
1012 		for (psf=pmc->tomb; psf; psf=psf_next) {
1013 			psf_next = psf->sf_next;
1014 			kfree(psf);
1015 		}
1016 		in_dev_put(pmc->interface);
1017 		kfree(pmc);
1018 	}
1019 }
1020 
1021 static void igmpv3_clear_delrec(struct in_device *in_dev)
1022 {
1023 	struct ip_mc_list *pmc, *nextpmc;
1024 
1025 	spin_lock_bh(&in_dev->mc_tomb_lock);
1026 	pmc = in_dev->mc_tomb;
1027 	in_dev->mc_tomb = NULL;
1028 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1029 
1030 	for (; pmc; pmc = nextpmc) {
1031 		nextpmc = pmc->next;
1032 		ip_mc_clear_src(pmc);
1033 		in_dev_put(pmc->interface);
1034 		kfree(pmc);
1035 	}
1036 	/* clear dead sources, too */
1037 	read_lock(&in_dev->mc_list_lock);
1038 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1039 		struct ip_sf_list *psf, *psf_next;
1040 
1041 		spin_lock_bh(&pmc->lock);
1042 		psf = pmc->tomb;
1043 		pmc->tomb = NULL;
1044 		spin_unlock_bh(&pmc->lock);
1045 		for (; psf; psf=psf_next) {
1046 			psf_next = psf->sf_next;
1047 			kfree(psf);
1048 		}
1049 	}
1050 	read_unlock(&in_dev->mc_list_lock);
1051 }
1052 #endif
1053 
1054 static void igmp_group_dropped(struct ip_mc_list *im)
1055 {
1056 	struct in_device *in_dev = im->interface;
1057 #ifdef CONFIG_IP_MULTICAST
1058 	int reporter;
1059 #endif
1060 
1061 	if (im->loaded) {
1062 		im->loaded = 0;
1063 		ip_mc_filter_del(in_dev, im->multiaddr);
1064 	}
1065 
1066 #ifdef CONFIG_IP_MULTICAST
1067 	if (im->multiaddr == IGMP_ALL_HOSTS)
1068 		return;
1069 
1070 	reporter = im->reporter;
1071 	igmp_stop_timer(im);
1072 
1073 	if (!in_dev->dead) {
1074 		if (IGMP_V1_SEEN(in_dev))
1075 			goto done;
1076 		if (IGMP_V2_SEEN(in_dev)) {
1077 			if (reporter)
1078 				igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1079 			goto done;
1080 		}
1081 		/* IGMPv3 */
1082 		igmpv3_add_delrec(in_dev, im);
1083 
1084 		igmp_ifc_event(in_dev);
1085 	}
1086 done:
1087 #endif
1088 	ip_mc_clear_src(im);
1089 }
1090 
1091 static void igmp_group_added(struct ip_mc_list *im)
1092 {
1093 	struct in_device *in_dev = im->interface;
1094 
1095 	if (im->loaded == 0) {
1096 		im->loaded = 1;
1097 		ip_mc_filter_add(in_dev, im->multiaddr);
1098 	}
1099 
1100 #ifdef CONFIG_IP_MULTICAST
1101 	if (im->multiaddr == IGMP_ALL_HOSTS)
1102 		return;
1103 
1104 	if (in_dev->dead)
1105 		return;
1106 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1107 		spin_lock_bh(&im->lock);
1108 		igmp_start_timer(im, IGMP_Initial_Report_Delay);
1109 		spin_unlock_bh(&im->lock);
1110 		return;
1111 	}
1112 	/* else, v3 */
1113 
1114 	im->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1115 		IGMP_Unsolicited_Report_Count;
1116 	igmp_ifc_event(in_dev);
1117 #endif
1118 }
1119 
1120 
1121 /*
1122  *	Multicast list managers
1123  */
1124 
1125 
1126 /*
1127  *	A socket has joined a multicast group on device dev.
1128  */
1129 
1130 void ip_mc_inc_group(struct in_device *in_dev, u32 addr)
1131 {
1132 	struct ip_mc_list *im;
1133 
1134 	ASSERT_RTNL();
1135 
1136 	for (im=in_dev->mc_list; im; im=im->next) {
1137 		if (im->multiaddr == addr) {
1138 			im->users++;
1139 			ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1140 			goto out;
1141 		}
1142 	}
1143 
1144 	im = (struct ip_mc_list *)kmalloc(sizeof(*im), GFP_KERNEL);
1145 	if (!im)
1146 		goto out;
1147 
1148 	im->users=1;
1149 	im->interface=in_dev;
1150 	in_dev_hold(in_dev);
1151 	im->multiaddr=addr;
1152 	/* initial mode is (EX, empty) */
1153 	im->sfmode = MCAST_EXCLUDE;
1154 	im->sfcount[MCAST_INCLUDE] = 0;
1155 	im->sfcount[MCAST_EXCLUDE] = 1;
1156 	im->sources = NULL;
1157 	im->tomb = NULL;
1158 	im->crcount = 0;
1159 	atomic_set(&im->refcnt, 1);
1160 	spin_lock_init(&im->lock);
1161 #ifdef CONFIG_IP_MULTICAST
1162 	im->tm_running=0;
1163 	init_timer(&im->timer);
1164 	im->timer.data=(unsigned long)im;
1165 	im->timer.function=&igmp_timer_expire;
1166 	im->unsolicit_count = IGMP_Unsolicited_Report_Count;
1167 	im->reporter = 0;
1168 	im->gsquery = 0;
1169 #endif
1170 	im->loaded = 0;
1171 	write_lock_bh(&in_dev->mc_list_lock);
1172 	im->next=in_dev->mc_list;
1173 	in_dev->mc_list=im;
1174 	write_unlock_bh(&in_dev->mc_list_lock);
1175 #ifdef CONFIG_IP_MULTICAST
1176 	igmpv3_del_delrec(in_dev, im->multiaddr);
1177 #endif
1178 	igmp_group_added(im);
1179 	if (!in_dev->dead)
1180 		ip_rt_multicast_event(in_dev);
1181 out:
1182 	return;
1183 }
1184 
1185 /*
1186  *	A socket has left a multicast group on device dev
1187  */
1188 
1189 void ip_mc_dec_group(struct in_device *in_dev, u32 addr)
1190 {
1191 	struct ip_mc_list *i, **ip;
1192 
1193 	ASSERT_RTNL();
1194 
1195 	for (ip=&in_dev->mc_list; (i=*ip)!=NULL; ip=&i->next) {
1196 		if (i->multiaddr==addr) {
1197 			if (--i->users == 0) {
1198 				write_lock_bh(&in_dev->mc_list_lock);
1199 				*ip = i->next;
1200 				write_unlock_bh(&in_dev->mc_list_lock);
1201 				igmp_group_dropped(i);
1202 
1203 				if (!in_dev->dead)
1204 					ip_rt_multicast_event(in_dev);
1205 
1206 				ip_ma_put(i);
1207 				return;
1208 			}
1209 			break;
1210 		}
1211 	}
1212 }
1213 
1214 /* Device going down */
1215 
1216 void ip_mc_down(struct in_device *in_dev)
1217 {
1218 	struct ip_mc_list *i;
1219 
1220 	ASSERT_RTNL();
1221 
1222 	for (i=in_dev->mc_list; i; i=i->next)
1223 		igmp_group_dropped(i);
1224 
1225 #ifdef CONFIG_IP_MULTICAST
1226 	in_dev->mr_ifc_count = 0;
1227 	if (del_timer(&in_dev->mr_ifc_timer))
1228 		__in_dev_put(in_dev);
1229 	in_dev->mr_gq_running = 0;
1230 	if (del_timer(&in_dev->mr_gq_timer))
1231 		__in_dev_put(in_dev);
1232 	igmpv3_clear_delrec(in_dev);
1233 #endif
1234 
1235 	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1236 }
1237 
1238 void ip_mc_init_dev(struct in_device *in_dev)
1239 {
1240 	ASSERT_RTNL();
1241 
1242 	in_dev->mc_tomb = NULL;
1243 #ifdef CONFIG_IP_MULTICAST
1244 	in_dev->mr_gq_running = 0;
1245 	init_timer(&in_dev->mr_gq_timer);
1246 	in_dev->mr_gq_timer.data=(unsigned long) in_dev;
1247 	in_dev->mr_gq_timer.function=&igmp_gq_timer_expire;
1248 	in_dev->mr_ifc_count = 0;
1249 	init_timer(&in_dev->mr_ifc_timer);
1250 	in_dev->mr_ifc_timer.data=(unsigned long) in_dev;
1251 	in_dev->mr_ifc_timer.function=&igmp_ifc_timer_expire;
1252 	in_dev->mr_qrv = IGMP_Unsolicited_Report_Count;
1253 #endif
1254 
1255 	rwlock_init(&in_dev->mc_list_lock);
1256 	spin_lock_init(&in_dev->mc_tomb_lock);
1257 }
1258 
1259 /* Device going up */
1260 
1261 void ip_mc_up(struct in_device *in_dev)
1262 {
1263 	struct ip_mc_list *i;
1264 
1265 	ASSERT_RTNL();
1266 
1267 	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1268 
1269 	for (i=in_dev->mc_list; i; i=i->next)
1270 		igmp_group_added(i);
1271 }
1272 
1273 /*
1274  *	Device is about to be destroyed: clean up.
1275  */
1276 
1277 void ip_mc_destroy_dev(struct in_device *in_dev)
1278 {
1279 	struct ip_mc_list *i;
1280 
1281 	ASSERT_RTNL();
1282 
1283 	/* Deactivate timers */
1284 	ip_mc_down(in_dev);
1285 
1286 	write_lock_bh(&in_dev->mc_list_lock);
1287 	while ((i = in_dev->mc_list) != NULL) {
1288 		in_dev->mc_list = i->next;
1289 		write_unlock_bh(&in_dev->mc_list_lock);
1290 
1291 		igmp_group_dropped(i);
1292 		ip_ma_put(i);
1293 
1294 		write_lock_bh(&in_dev->mc_list_lock);
1295 	}
1296 	write_unlock_bh(&in_dev->mc_list_lock);
1297 }
1298 
1299 static struct in_device * ip_mc_find_dev(struct ip_mreqn *imr)
1300 {
1301 	struct flowi fl = { .nl_u = { .ip4_u =
1302 				      { .daddr = imr->imr_multiaddr.s_addr } } };
1303 	struct rtable *rt;
1304 	struct net_device *dev = NULL;
1305 	struct in_device *idev = NULL;
1306 
1307 	if (imr->imr_ifindex) {
1308 		idev = inetdev_by_index(imr->imr_ifindex);
1309 		if (idev)
1310 			__in_dev_put(idev);
1311 		return idev;
1312 	}
1313 	if (imr->imr_address.s_addr) {
1314 		dev = ip_dev_find(imr->imr_address.s_addr);
1315 		if (!dev)
1316 			return NULL;
1317 		__dev_put(dev);
1318 	}
1319 
1320 	if (!dev && !ip_route_output_key(&rt, &fl)) {
1321 		dev = rt->u.dst.dev;
1322 		ip_rt_put(rt);
1323 	}
1324 	if (dev) {
1325 		imr->imr_ifindex = dev->ifindex;
1326 		idev = __in_dev_get(dev);
1327 	}
1328 	return idev;
1329 }
1330 
1331 /*
1332  *	Join a socket to a group
1333  */
1334 int sysctl_igmp_max_memberships = IP_MAX_MEMBERSHIPS;
1335 int sysctl_igmp_max_msf = IP_MAX_MSF;
1336 
1337 
1338 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1339 	__u32 *psfsrc)
1340 {
1341 	struct ip_sf_list *psf, *psf_prev;
1342 	int rv = 0;
1343 
1344 	psf_prev = NULL;
1345 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1346 		if (psf->sf_inaddr == *psfsrc)
1347 			break;
1348 		psf_prev = psf;
1349 	}
1350 	if (!psf || psf->sf_count[sfmode] == 0) {
1351 		/* source filter not found, or count wrong =>  bug */
1352 		return -ESRCH;
1353 	}
1354 	psf->sf_count[sfmode]--;
1355 	if (psf->sf_count[sfmode] == 0) {
1356 		ip_rt_multicast_event(pmc->interface);
1357 	}
1358 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1359 #ifdef CONFIG_IP_MULTICAST
1360 		struct in_device *in_dev = pmc->interface;
1361 #endif
1362 
1363 		/* no more filters for this source */
1364 		if (psf_prev)
1365 			psf_prev->sf_next = psf->sf_next;
1366 		else
1367 			pmc->sources = psf->sf_next;
1368 #ifdef CONFIG_IP_MULTICAST
1369 		if (psf->sf_oldin &&
1370 		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1371 			psf->sf_crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1372 				IGMP_Unsolicited_Report_Count;
1373 			psf->sf_next = pmc->tomb;
1374 			pmc->tomb = psf;
1375 			rv = 1;
1376 		} else
1377 #endif
1378 			kfree(psf);
1379 	}
1380 	return rv;
1381 }
1382 
1383 #ifndef CONFIG_IP_MULTICAST
1384 #define igmp_ifc_event(x)	do { } while (0)
1385 #endif
1386 
1387 static int ip_mc_del_src(struct in_device *in_dev, __u32 *pmca, int sfmode,
1388 			 int sfcount, __u32 *psfsrc, int delta)
1389 {
1390 	struct ip_mc_list *pmc;
1391 	int	changerec = 0;
1392 	int	i, err;
1393 
1394 	if (!in_dev)
1395 		return -ENODEV;
1396 	read_lock(&in_dev->mc_list_lock);
1397 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1398 		if (*pmca == pmc->multiaddr)
1399 			break;
1400 	}
1401 	if (!pmc) {
1402 		/* MCA not found?? bug */
1403 		read_unlock(&in_dev->mc_list_lock);
1404 		return -ESRCH;
1405 	}
1406 	spin_lock_bh(&pmc->lock);
1407 	read_unlock(&in_dev->mc_list_lock);
1408 #ifdef CONFIG_IP_MULTICAST
1409 	sf_markstate(pmc);
1410 #endif
1411 	if (!delta) {
1412 		err = -EINVAL;
1413 		if (!pmc->sfcount[sfmode])
1414 			goto out_unlock;
1415 		pmc->sfcount[sfmode]--;
1416 	}
1417 	err = 0;
1418 	for (i=0; i<sfcount; i++) {
1419 		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1420 
1421 		changerec |= rv > 0;
1422 		if (!err && rv < 0)
1423 			err = rv;
1424 	}
1425 	if (pmc->sfmode == MCAST_EXCLUDE &&
1426 	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1427 	    pmc->sfcount[MCAST_INCLUDE]) {
1428 #ifdef CONFIG_IP_MULTICAST
1429 		struct ip_sf_list *psf;
1430 #endif
1431 
1432 		/* filter mode change */
1433 		pmc->sfmode = MCAST_INCLUDE;
1434 #ifdef CONFIG_IP_MULTICAST
1435 		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1436 			IGMP_Unsolicited_Report_Count;
1437 		in_dev->mr_ifc_count = pmc->crcount;
1438 		for (psf=pmc->sources; psf; psf = psf->sf_next)
1439 			psf->sf_crcount = 0;
1440 		igmp_ifc_event(pmc->interface);
1441 	} else if (sf_setstate(pmc) || changerec) {
1442 		igmp_ifc_event(pmc->interface);
1443 #endif
1444 	}
1445 out_unlock:
1446 	spin_unlock_bh(&pmc->lock);
1447 	return err;
1448 }
1449 
1450 /*
1451  * Add multicast single-source filter to the interface list
1452  */
1453 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1454 	__u32 *psfsrc, int delta)
1455 {
1456 	struct ip_sf_list *psf, *psf_prev;
1457 
1458 	psf_prev = NULL;
1459 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1460 		if (psf->sf_inaddr == *psfsrc)
1461 			break;
1462 		psf_prev = psf;
1463 	}
1464 	if (!psf) {
1465 		psf = (struct ip_sf_list *)kmalloc(sizeof(*psf), GFP_ATOMIC);
1466 		if (!psf)
1467 			return -ENOBUFS;
1468 		memset(psf, 0, sizeof(*psf));
1469 		psf->sf_inaddr = *psfsrc;
1470 		if (psf_prev) {
1471 			psf_prev->sf_next = psf;
1472 		} else
1473 			pmc->sources = psf;
1474 	}
1475 	psf->sf_count[sfmode]++;
1476 	if (psf->sf_count[sfmode] == 1) {
1477 		ip_rt_multicast_event(pmc->interface);
1478 	}
1479 	return 0;
1480 }
1481 
1482 #ifdef CONFIG_IP_MULTICAST
1483 static void sf_markstate(struct ip_mc_list *pmc)
1484 {
1485 	struct ip_sf_list *psf;
1486 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1487 
1488 	for (psf=pmc->sources; psf; psf=psf->sf_next)
1489 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1490 			psf->sf_oldin = mca_xcount ==
1491 				psf->sf_count[MCAST_EXCLUDE] &&
1492 				!psf->sf_count[MCAST_INCLUDE];
1493 		} else
1494 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1495 }
1496 
1497 static int sf_setstate(struct ip_mc_list *pmc)
1498 {
1499 	struct ip_sf_list *psf;
1500 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1501 	int qrv = pmc->interface->mr_qrv;
1502 	int new_in, rv;
1503 
1504 	rv = 0;
1505 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1506 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1507 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1508 				!psf->sf_count[MCAST_INCLUDE];
1509 		} else
1510 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1511 		if (new_in != psf->sf_oldin) {
1512 			psf->sf_crcount = qrv;
1513 			rv++;
1514 		}
1515 	}
1516 	return rv;
1517 }
1518 #endif
1519 
1520 /*
1521  * Add multicast source filter list to the interface list
1522  */
1523 static int ip_mc_add_src(struct in_device *in_dev, __u32 *pmca, int sfmode,
1524 			 int sfcount, __u32 *psfsrc, int delta)
1525 {
1526 	struct ip_mc_list *pmc;
1527 	int	isexclude;
1528 	int	i, err;
1529 
1530 	if (!in_dev)
1531 		return -ENODEV;
1532 	read_lock(&in_dev->mc_list_lock);
1533 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1534 		if (*pmca == pmc->multiaddr)
1535 			break;
1536 	}
1537 	if (!pmc) {
1538 		/* MCA not found?? bug */
1539 		read_unlock(&in_dev->mc_list_lock);
1540 		return -ESRCH;
1541 	}
1542 	spin_lock_bh(&pmc->lock);
1543 	read_unlock(&in_dev->mc_list_lock);
1544 
1545 #ifdef CONFIG_IP_MULTICAST
1546 	sf_markstate(pmc);
1547 #endif
1548 	isexclude = pmc->sfmode == MCAST_EXCLUDE;
1549 	if (!delta)
1550 		pmc->sfcount[sfmode]++;
1551 	err = 0;
1552 	for (i=0; i<sfcount; i++) {
1553 		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i], delta);
1554 		if (err)
1555 			break;
1556 	}
1557 	if (err) {
1558 		int j;
1559 
1560 		pmc->sfcount[sfmode]--;
1561 		for (j=0; j<i; j++)
1562 			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1563 	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
1564 #ifdef CONFIG_IP_MULTICAST
1565 		struct in_device *in_dev = pmc->interface;
1566 		struct ip_sf_list *psf;
1567 #endif
1568 
1569 		/* filter mode change */
1570 		if (pmc->sfcount[MCAST_EXCLUDE])
1571 			pmc->sfmode = MCAST_EXCLUDE;
1572 		else if (pmc->sfcount[MCAST_INCLUDE])
1573 			pmc->sfmode = MCAST_INCLUDE;
1574 #ifdef CONFIG_IP_MULTICAST
1575 		/* else no filters; keep old mode for reports */
1576 
1577 		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1578 			IGMP_Unsolicited_Report_Count;
1579 		in_dev->mr_ifc_count = pmc->crcount;
1580 		for (psf=pmc->sources; psf; psf = psf->sf_next)
1581 			psf->sf_crcount = 0;
1582 		igmp_ifc_event(in_dev);
1583 	} else if (sf_setstate(pmc)) {
1584 		igmp_ifc_event(in_dev);
1585 #endif
1586 	}
1587 	spin_unlock_bh(&pmc->lock);
1588 	return err;
1589 }
1590 
1591 static void ip_mc_clear_src(struct ip_mc_list *pmc)
1592 {
1593 	struct ip_sf_list *psf, *nextpsf;
1594 
1595 	for (psf=pmc->tomb; psf; psf=nextpsf) {
1596 		nextpsf = psf->sf_next;
1597 		kfree(psf);
1598 	}
1599 	pmc->tomb = NULL;
1600 	for (psf=pmc->sources; psf; psf=nextpsf) {
1601 		nextpsf = psf->sf_next;
1602 		kfree(psf);
1603 	}
1604 	pmc->sources = NULL;
1605 	pmc->sfmode = MCAST_EXCLUDE;
1606 	pmc->sfcount[MCAST_INCLUDE] = 0;
1607 	pmc->sfcount[MCAST_EXCLUDE] = 1;
1608 }
1609 
1610 
1611 /*
1612  * Join a multicast group
1613  */
1614 int ip_mc_join_group(struct sock *sk , struct ip_mreqn *imr)
1615 {
1616 	int err;
1617 	u32 addr = imr->imr_multiaddr.s_addr;
1618 	struct ip_mc_socklist *iml=NULL, *i;
1619 	struct in_device *in_dev;
1620 	struct inet_sock *inet = inet_sk(sk);
1621 	int ifindex;
1622 	int count = 0;
1623 
1624 	if (!MULTICAST(addr))
1625 		return -EINVAL;
1626 
1627 	rtnl_shlock();
1628 
1629 	in_dev = ip_mc_find_dev(imr);
1630 
1631 	if (!in_dev) {
1632 		iml = NULL;
1633 		err = -ENODEV;
1634 		goto done;
1635 	}
1636 
1637 	err = -EADDRINUSE;
1638 	ifindex = imr->imr_ifindex;
1639 	for (i = inet->mc_list; i; i = i->next) {
1640 		if (i->multi.imr_multiaddr.s_addr == addr &&
1641 		    i->multi.imr_ifindex == ifindex)
1642 			goto done;
1643 		count++;
1644 	}
1645 	err = -ENOBUFS;
1646 	if (count >= sysctl_igmp_max_memberships)
1647 		goto done;
1648 	iml = (struct ip_mc_socklist *)sock_kmalloc(sk,sizeof(*iml),GFP_KERNEL);
1649 	if (iml == NULL)
1650 		goto done;
1651 
1652 	memcpy(&iml->multi, imr, sizeof(*imr));
1653 	iml->next = inet->mc_list;
1654 	iml->sflist = NULL;
1655 	iml->sfmode = MCAST_EXCLUDE;
1656 	inet->mc_list = iml;
1657 	ip_mc_inc_group(in_dev, addr);
1658 	err = 0;
1659 done:
1660 	rtnl_shunlock();
1661 	return err;
1662 }
1663 
1664 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
1665 			   struct in_device *in_dev)
1666 {
1667 	int err;
1668 
1669 	if (iml->sflist == 0) {
1670 		/* any-source empty exclude case */
1671 		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1672 			iml->sfmode, 0, NULL, 0);
1673 	}
1674 	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1675 			iml->sfmode, iml->sflist->sl_count,
1676 			iml->sflist->sl_addr, 0);
1677 	sock_kfree_s(sk, iml->sflist, IP_SFLSIZE(iml->sflist->sl_max));
1678 	iml->sflist = NULL;
1679 	return err;
1680 }
1681 
1682 /*
1683  *	Ask a socket to leave a group.
1684  */
1685 
1686 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
1687 {
1688 	struct inet_sock *inet = inet_sk(sk);
1689 	struct ip_mc_socklist *iml, **imlp;
1690 	struct in_device *in_dev;
1691 	u32 group = imr->imr_multiaddr.s_addr;
1692 	u32 ifindex;
1693 
1694 	rtnl_lock();
1695 	in_dev = ip_mc_find_dev(imr);
1696 	if (!in_dev) {
1697 		rtnl_unlock();
1698 		return -ENODEV;
1699 	}
1700 	ifindex = imr->imr_ifindex;
1701 	for (imlp = &inet->mc_list; (iml = *imlp) != NULL; imlp = &iml->next) {
1702 		if (iml->multi.imr_multiaddr.s_addr == group &&
1703 		    iml->multi.imr_ifindex == ifindex) {
1704 			(void) ip_mc_leave_src(sk, iml, in_dev);
1705 
1706 			*imlp = iml->next;
1707 
1708 			ip_mc_dec_group(in_dev, group);
1709 			rtnl_unlock();
1710 			sock_kfree_s(sk, iml, sizeof(*iml));
1711 			return 0;
1712 		}
1713 	}
1714 	rtnl_unlock();
1715 	return -EADDRNOTAVAIL;
1716 }
1717 
1718 int ip_mc_source(int add, int omode, struct sock *sk, struct
1719 	ip_mreq_source *mreqs, int ifindex)
1720 {
1721 	int err;
1722 	struct ip_mreqn imr;
1723 	u32 addr = mreqs->imr_multiaddr;
1724 	struct ip_mc_socklist *pmc;
1725 	struct in_device *in_dev = NULL;
1726 	struct inet_sock *inet = inet_sk(sk);
1727 	struct ip_sf_socklist *psl;
1728 	int leavegroup = 0;
1729 	int i, j, rv;
1730 
1731 	if (!MULTICAST(addr))
1732 		return -EINVAL;
1733 
1734 	rtnl_shlock();
1735 
1736 	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
1737 	imr.imr_address.s_addr = mreqs->imr_interface;
1738 	imr.imr_ifindex = ifindex;
1739 	in_dev = ip_mc_find_dev(&imr);
1740 
1741 	if (!in_dev) {
1742 		err = -ENODEV;
1743 		goto done;
1744 	}
1745 	err = -EADDRNOTAVAIL;
1746 
1747 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
1748 		if (pmc->multi.imr_multiaddr.s_addr == imr.imr_multiaddr.s_addr
1749 		    && pmc->multi.imr_ifindex == imr.imr_ifindex)
1750 			break;
1751 	}
1752 	if (!pmc) {		/* must have a prior join */
1753 		err = -EINVAL;
1754 		goto done;
1755 	}
1756 	/* if a source filter was set, must be the same mode as before */
1757 	if (pmc->sflist) {
1758 		if (pmc->sfmode != omode) {
1759 			err = -EINVAL;
1760 			goto done;
1761 		}
1762 	} else if (pmc->sfmode != omode) {
1763 		/* allow mode switches for empty-set filters */
1764 		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
1765 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
1766 			NULL, 0);
1767 		pmc->sfmode = omode;
1768 	}
1769 
1770 	psl = pmc->sflist;
1771 	if (!add) {
1772 		if (!psl)
1773 			goto done;	/* err = -EADDRNOTAVAIL */
1774 		rv = !0;
1775 		for (i=0; i<psl->sl_count; i++) {
1776 			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1777 				sizeof(__u32));
1778 			if (rv == 0)
1779 				break;
1780 		}
1781 		if (rv)		/* source not found */
1782 			goto done;	/* err = -EADDRNOTAVAIL */
1783 
1784 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
1785 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
1786 			leavegroup = 1;
1787 			goto done;
1788 		}
1789 
1790 		/* update the interface filter */
1791 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1792 			&mreqs->imr_sourceaddr, 1);
1793 
1794 		for (j=i+1; j<psl->sl_count; j++)
1795 			psl->sl_addr[j-1] = psl->sl_addr[j];
1796 		psl->sl_count--;
1797 		err = 0;
1798 		goto done;
1799 	}
1800 	/* else, add a new source to the filter */
1801 
1802 	if (psl && psl->sl_count >= sysctl_igmp_max_msf) {
1803 		err = -ENOBUFS;
1804 		goto done;
1805 	}
1806 	if (!psl || psl->sl_count == psl->sl_max) {
1807 		struct ip_sf_socklist *newpsl;
1808 		int count = IP_SFBLOCK;
1809 
1810 		if (psl)
1811 			count += psl->sl_max;
1812 		newpsl = (struct ip_sf_socklist *)sock_kmalloc(sk,
1813 			IP_SFLSIZE(count), GFP_KERNEL);
1814 		if (!newpsl) {
1815 			err = -ENOBUFS;
1816 			goto done;
1817 		}
1818 		newpsl->sl_max = count;
1819 		newpsl->sl_count = count - IP_SFBLOCK;
1820 		if (psl) {
1821 			for (i=0; i<psl->sl_count; i++)
1822 				newpsl->sl_addr[i] = psl->sl_addr[i];
1823 			sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
1824 		}
1825 		pmc->sflist = psl = newpsl;
1826 	}
1827 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
1828 	for (i=0; i<psl->sl_count; i++) {
1829 		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1830 			sizeof(__u32));
1831 		if (rv == 0)
1832 			break;
1833 	}
1834 	if (rv == 0)		/* address already there is an error */
1835 		goto done;
1836 	for (j=psl->sl_count-1; j>=i; j--)
1837 		psl->sl_addr[j+1] = psl->sl_addr[j];
1838 	psl->sl_addr[i] = mreqs->imr_sourceaddr;
1839 	psl->sl_count++;
1840 	err = 0;
1841 	/* update the interface list */
1842 	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1843 		&mreqs->imr_sourceaddr, 1);
1844 done:
1845 	rtnl_shunlock();
1846 	if (leavegroup)
1847 		return ip_mc_leave_group(sk, &imr);
1848 	return err;
1849 }
1850 
1851 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
1852 {
1853 	int err = 0;
1854 	struct ip_mreqn	imr;
1855 	u32 addr = msf->imsf_multiaddr;
1856 	struct ip_mc_socklist *pmc;
1857 	struct in_device *in_dev;
1858 	struct inet_sock *inet = inet_sk(sk);
1859 	struct ip_sf_socklist *newpsl, *psl;
1860 	int leavegroup = 0;
1861 
1862 	if (!MULTICAST(addr))
1863 		return -EINVAL;
1864 	if (msf->imsf_fmode != MCAST_INCLUDE &&
1865 	    msf->imsf_fmode != MCAST_EXCLUDE)
1866 		return -EINVAL;
1867 
1868 	rtnl_shlock();
1869 
1870 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
1871 	imr.imr_address.s_addr = msf->imsf_interface;
1872 	imr.imr_ifindex = ifindex;
1873 	in_dev = ip_mc_find_dev(&imr);
1874 
1875 	if (!in_dev) {
1876 		err = -ENODEV;
1877 		goto done;
1878 	}
1879 
1880 	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
1881 	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
1882 		leavegroup = 1;
1883 		goto done;
1884 	}
1885 
1886 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
1887 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
1888 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
1889 			break;
1890 	}
1891 	if (!pmc) {		/* must have a prior join */
1892 		err = -EINVAL;
1893 		goto done;
1894 	}
1895 	if (msf->imsf_numsrc) {
1896 		newpsl = (struct ip_sf_socklist *)sock_kmalloc(sk,
1897 				IP_SFLSIZE(msf->imsf_numsrc), GFP_KERNEL);
1898 		if (!newpsl) {
1899 			err = -ENOBUFS;
1900 			goto done;
1901 		}
1902 		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
1903 		memcpy(newpsl->sl_addr, msf->imsf_slist,
1904 			msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
1905 		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
1906 			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
1907 		if (err) {
1908 			sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
1909 			goto done;
1910 		}
1911 	} else
1912 		newpsl = NULL;
1913 	psl = pmc->sflist;
1914 	if (psl) {
1915 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
1916 			psl->sl_count, psl->sl_addr, 0);
1917 		sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
1918 	} else
1919 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
1920 			0, NULL, 0);
1921 	pmc->sflist = newpsl;
1922 	pmc->sfmode = msf->imsf_fmode;
1923 	err = 0;
1924 done:
1925 	rtnl_shunlock();
1926 	if (leavegroup)
1927 		err = ip_mc_leave_group(sk, &imr);
1928 	return err;
1929 }
1930 
1931 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
1932 	struct ip_msfilter __user *optval, int __user *optlen)
1933 {
1934 	int err, len, count, copycount;
1935 	struct ip_mreqn	imr;
1936 	u32 addr = msf->imsf_multiaddr;
1937 	struct ip_mc_socklist *pmc;
1938 	struct in_device *in_dev;
1939 	struct inet_sock *inet = inet_sk(sk);
1940 	struct ip_sf_socklist *psl;
1941 
1942 	if (!MULTICAST(addr))
1943 		return -EINVAL;
1944 
1945 	rtnl_shlock();
1946 
1947 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
1948 	imr.imr_address.s_addr = msf->imsf_interface;
1949 	imr.imr_ifindex = 0;
1950 	in_dev = ip_mc_find_dev(&imr);
1951 
1952 	if (!in_dev) {
1953 		err = -ENODEV;
1954 		goto done;
1955 	}
1956 	err = -EADDRNOTAVAIL;
1957 
1958 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
1959 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
1960 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
1961 			break;
1962 	}
1963 	if (!pmc)		/* must have a prior join */
1964 		goto done;
1965 	msf->imsf_fmode = pmc->sfmode;
1966 	psl = pmc->sflist;
1967 	rtnl_shunlock();
1968 	if (!psl) {
1969 		len = 0;
1970 		count = 0;
1971 	} else {
1972 		count = psl->sl_count;
1973 	}
1974 	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
1975 	len = copycount * sizeof(psl->sl_addr[0]);
1976 	msf->imsf_numsrc = count;
1977 	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
1978 	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
1979 		return -EFAULT;
1980 	}
1981 	if (len &&
1982 	    copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
1983 		return -EFAULT;
1984 	return 0;
1985 done:
1986 	rtnl_shunlock();
1987 	return err;
1988 }
1989 
1990 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
1991 	struct group_filter __user *optval, int __user *optlen)
1992 {
1993 	int err, i, count, copycount;
1994 	struct sockaddr_in *psin;
1995 	u32 addr;
1996 	struct ip_mc_socklist *pmc;
1997 	struct inet_sock *inet = inet_sk(sk);
1998 	struct ip_sf_socklist *psl;
1999 
2000 	psin = (struct sockaddr_in *)&gsf->gf_group;
2001 	if (psin->sin_family != AF_INET)
2002 		return -EINVAL;
2003 	addr = psin->sin_addr.s_addr;
2004 	if (!MULTICAST(addr))
2005 		return -EINVAL;
2006 
2007 	rtnl_shlock();
2008 
2009 	err = -EADDRNOTAVAIL;
2010 
2011 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2012 		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2013 		    pmc->multi.imr_ifindex == gsf->gf_interface)
2014 			break;
2015 	}
2016 	if (!pmc)		/* must have a prior join */
2017 		goto done;
2018 	gsf->gf_fmode = pmc->sfmode;
2019 	psl = pmc->sflist;
2020 	rtnl_shunlock();
2021 	count = psl ? psl->sl_count : 0;
2022 	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2023 	gsf->gf_numsrc = count;
2024 	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2025 	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2026 		return -EFAULT;
2027 	}
2028 	for (i=0; i<copycount; i++) {
2029 		struct sockaddr_in *psin;
2030 		struct sockaddr_storage ss;
2031 
2032 		psin = (struct sockaddr_in *)&ss;
2033 		memset(&ss, 0, sizeof(ss));
2034 		psin->sin_family = AF_INET;
2035 		psin->sin_addr.s_addr = psl->sl_addr[i];
2036 		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2037 			return -EFAULT;
2038 	}
2039 	return 0;
2040 done:
2041 	rtnl_shunlock();
2042 	return err;
2043 }
2044 
2045 /*
2046  * check if a multicast source filter allows delivery for a given <src,dst,intf>
2047  */
2048 int ip_mc_sf_allow(struct sock *sk, u32 loc_addr, u32 rmt_addr, int dif)
2049 {
2050 	struct inet_sock *inet = inet_sk(sk);
2051 	struct ip_mc_socklist *pmc;
2052 	struct ip_sf_socklist *psl;
2053 	int i;
2054 
2055 	if (!MULTICAST(loc_addr))
2056 		return 1;
2057 
2058 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2059 		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2060 		    pmc->multi.imr_ifindex == dif)
2061 			break;
2062 	}
2063 	if (!pmc)
2064 		return 1;
2065 	psl = pmc->sflist;
2066 	if (!psl)
2067 		return pmc->sfmode == MCAST_EXCLUDE;
2068 
2069 	for (i=0; i<psl->sl_count; i++) {
2070 		if (psl->sl_addr[i] == rmt_addr)
2071 			break;
2072 	}
2073 	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2074 		return 0;
2075 	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2076 		return 0;
2077 	return 1;
2078 }
2079 
2080 /*
2081  *	A socket is closing.
2082  */
2083 
2084 void ip_mc_drop_socket(struct sock *sk)
2085 {
2086 	struct inet_sock *inet = inet_sk(sk);
2087 	struct ip_mc_socklist *iml;
2088 
2089 	if (inet->mc_list == NULL)
2090 		return;
2091 
2092 	rtnl_lock();
2093 	while ((iml = inet->mc_list) != NULL) {
2094 		struct in_device *in_dev;
2095 		inet->mc_list = iml->next;
2096 
2097 		if ((in_dev = inetdev_by_index(iml->multi.imr_ifindex)) != NULL) {
2098 			(void) ip_mc_leave_src(sk, iml, in_dev);
2099 			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2100 			in_dev_put(in_dev);
2101 		}
2102 		sock_kfree_s(sk, iml, sizeof(*iml));
2103 
2104 	}
2105 	rtnl_unlock();
2106 }
2107 
2108 int ip_check_mc(struct in_device *in_dev, u32 mc_addr, u32 src_addr, u16 proto)
2109 {
2110 	struct ip_mc_list *im;
2111 	struct ip_sf_list *psf;
2112 	int rv = 0;
2113 
2114 	read_lock(&in_dev->mc_list_lock);
2115 	for (im=in_dev->mc_list; im; im=im->next) {
2116 		if (im->multiaddr == mc_addr)
2117 			break;
2118 	}
2119 	if (im && proto == IPPROTO_IGMP) {
2120 		rv = 1;
2121 	} else if (im) {
2122 		if (src_addr) {
2123 			for (psf=im->sources; psf; psf=psf->sf_next) {
2124 				if (psf->sf_inaddr == src_addr)
2125 					break;
2126 			}
2127 			if (psf)
2128 				rv = psf->sf_count[MCAST_INCLUDE] ||
2129 					psf->sf_count[MCAST_EXCLUDE] !=
2130 					im->sfcount[MCAST_EXCLUDE];
2131 			else
2132 				rv = im->sfcount[MCAST_EXCLUDE] != 0;
2133 		} else
2134 			rv = 1; /* unspecified source; tentatively allow */
2135 	}
2136 	read_unlock(&in_dev->mc_list_lock);
2137 	return rv;
2138 }
2139 
2140 #if defined(CONFIG_PROC_FS)
2141 struct igmp_mc_iter_state {
2142 	struct net_device *dev;
2143 	struct in_device *in_dev;
2144 };
2145 
2146 #define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2147 
2148 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2149 {
2150 	struct ip_mc_list *im = NULL;
2151 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2152 
2153 	for (state->dev = dev_base, state->in_dev = NULL;
2154 	     state->dev;
2155 	     state->dev = state->dev->next) {
2156 		struct in_device *in_dev;
2157 		in_dev = in_dev_get(state->dev);
2158 		if (!in_dev)
2159 			continue;
2160 		read_lock(&in_dev->mc_list_lock);
2161 		im = in_dev->mc_list;
2162 		if (im) {
2163 			state->in_dev = in_dev;
2164 			break;
2165 		}
2166 		read_unlock(&in_dev->mc_list_lock);
2167 		in_dev_put(in_dev);
2168 	}
2169 	return im;
2170 }
2171 
2172 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2173 {
2174 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2175 	im = im->next;
2176 	while (!im) {
2177 		if (likely(state->in_dev != NULL)) {
2178 			read_unlock(&state->in_dev->mc_list_lock);
2179 			in_dev_put(state->in_dev);
2180 		}
2181 		state->dev = state->dev->next;
2182 		if (!state->dev) {
2183 			state->in_dev = NULL;
2184 			break;
2185 		}
2186 		state->in_dev = in_dev_get(state->dev);
2187 		if (!state->in_dev)
2188 			continue;
2189 		read_lock(&state->in_dev->mc_list_lock);
2190 		im = state->in_dev->mc_list;
2191 	}
2192 	return im;
2193 }
2194 
2195 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2196 {
2197 	struct ip_mc_list *im = igmp_mc_get_first(seq);
2198 	if (im)
2199 		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2200 			--pos;
2201 	return pos ? NULL : im;
2202 }
2203 
2204 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2205 {
2206 	read_lock(&dev_base_lock);
2207 	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2208 }
2209 
2210 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2211 {
2212 	struct ip_mc_list *im;
2213 	if (v == SEQ_START_TOKEN)
2214 		im = igmp_mc_get_first(seq);
2215 	else
2216 		im = igmp_mc_get_next(seq, v);
2217 	++*pos;
2218 	return im;
2219 }
2220 
2221 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2222 {
2223 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2224 	if (likely(state->in_dev != NULL)) {
2225 		read_unlock(&state->in_dev->mc_list_lock);
2226 		in_dev_put(state->in_dev);
2227 		state->in_dev = NULL;
2228 	}
2229 	state->dev = NULL;
2230 	read_unlock(&dev_base_lock);
2231 }
2232 
2233 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2234 {
2235 	if (v == SEQ_START_TOKEN)
2236 		seq_puts(seq,
2237 			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2238 	else {
2239 		struct ip_mc_list *im = (struct ip_mc_list *)v;
2240 		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2241 		char   *querier;
2242 #ifdef CONFIG_IP_MULTICAST
2243 		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2244 			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2245 			  "V3";
2246 #else
2247 		querier = "NONE";
2248 #endif
2249 
2250 		if (state->in_dev->mc_list == im) {
2251 			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2252 				   state->dev->ifindex, state->dev->name, state->dev->mc_count, querier);
2253 		}
2254 
2255 		seq_printf(seq,
2256 			   "\t\t\t\t%08lX %5d %d:%08lX\t\t%d\n",
2257 			   im->multiaddr, im->users,
2258 			   im->tm_running, im->tm_running ?
2259 			   jiffies_to_clock_t(im->timer.expires-jiffies) : 0,
2260 			   im->reporter);
2261 	}
2262 	return 0;
2263 }
2264 
2265 static struct seq_operations igmp_mc_seq_ops = {
2266 	.start	=	igmp_mc_seq_start,
2267 	.next	=	igmp_mc_seq_next,
2268 	.stop	=	igmp_mc_seq_stop,
2269 	.show	=	igmp_mc_seq_show,
2270 };
2271 
2272 static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2273 {
2274 	struct seq_file *seq;
2275 	int rc = -ENOMEM;
2276 	struct igmp_mc_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL);
2277 
2278 	if (!s)
2279 		goto out;
2280 	rc = seq_open(file, &igmp_mc_seq_ops);
2281 	if (rc)
2282 		goto out_kfree;
2283 
2284 	seq = file->private_data;
2285 	seq->private = s;
2286 	memset(s, 0, sizeof(*s));
2287 out:
2288 	return rc;
2289 out_kfree:
2290 	kfree(s);
2291 	goto out;
2292 }
2293 
2294 static struct file_operations igmp_mc_seq_fops = {
2295 	.owner		=	THIS_MODULE,
2296 	.open		=	igmp_mc_seq_open,
2297 	.read		=	seq_read,
2298 	.llseek		=	seq_lseek,
2299 	.release	=	seq_release_private,
2300 };
2301 
2302 struct igmp_mcf_iter_state {
2303 	struct net_device *dev;
2304 	struct in_device *idev;
2305 	struct ip_mc_list *im;
2306 };
2307 
2308 #define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2309 
2310 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2311 {
2312 	struct ip_sf_list *psf = NULL;
2313 	struct ip_mc_list *im = NULL;
2314 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2315 
2316 	for (state->dev = dev_base, state->idev = NULL, state->im = NULL;
2317 	     state->dev;
2318 	     state->dev = state->dev->next) {
2319 		struct in_device *idev;
2320 		idev = in_dev_get(state->dev);
2321 		if (unlikely(idev == NULL))
2322 			continue;
2323 		read_lock(&idev->mc_list_lock);
2324 		im = idev->mc_list;
2325 		if (likely(im != NULL)) {
2326 			spin_lock_bh(&im->lock);
2327 			psf = im->sources;
2328 			if (likely(psf != NULL)) {
2329 				state->im = im;
2330 				state->idev = idev;
2331 				break;
2332 			}
2333 			spin_unlock_bh(&im->lock);
2334 		}
2335 		read_unlock(&idev->mc_list_lock);
2336 		in_dev_put(idev);
2337 	}
2338 	return psf;
2339 }
2340 
2341 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2342 {
2343 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2344 
2345 	psf = psf->sf_next;
2346 	while (!psf) {
2347 		spin_unlock_bh(&state->im->lock);
2348 		state->im = state->im->next;
2349 		while (!state->im) {
2350 			if (likely(state->idev != NULL)) {
2351 				read_unlock(&state->idev->mc_list_lock);
2352 				in_dev_put(state->idev);
2353 			}
2354 			state->dev = state->dev->next;
2355 			if (!state->dev) {
2356 				state->idev = NULL;
2357 				goto out;
2358 			}
2359 			state->idev = in_dev_get(state->dev);
2360 			if (!state->idev)
2361 				continue;
2362 			read_lock(&state->idev->mc_list_lock);
2363 			state->im = state->idev->mc_list;
2364 		}
2365 		if (!state->im)
2366 			break;
2367 		spin_lock_bh(&state->im->lock);
2368 		psf = state->im->sources;
2369 	}
2370 out:
2371 	return psf;
2372 }
2373 
2374 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2375 {
2376 	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2377 	if (psf)
2378 		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2379 			--pos;
2380 	return pos ? NULL : psf;
2381 }
2382 
2383 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2384 {
2385 	read_lock(&dev_base_lock);
2386 	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2387 }
2388 
2389 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2390 {
2391 	struct ip_sf_list *psf;
2392 	if (v == SEQ_START_TOKEN)
2393 		psf = igmp_mcf_get_first(seq);
2394 	else
2395 		psf = igmp_mcf_get_next(seq, v);
2396 	++*pos;
2397 	return psf;
2398 }
2399 
2400 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2401 {
2402 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2403 	if (likely(state->im != NULL)) {
2404 		spin_unlock_bh(&state->im->lock);
2405 		state->im = NULL;
2406 	}
2407 	if (likely(state->idev != NULL)) {
2408 		read_unlock(&state->idev->mc_list_lock);
2409 		in_dev_put(state->idev);
2410 		state->idev = NULL;
2411 	}
2412 	state->dev = NULL;
2413 	read_unlock(&dev_base_lock);
2414 }
2415 
2416 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2417 {
2418 	struct ip_sf_list *psf = (struct ip_sf_list *)v;
2419 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2420 
2421 	if (v == SEQ_START_TOKEN) {
2422 		seq_printf(seq,
2423 			   "%3s %6s "
2424 			   "%10s %10s %6s %6s\n", "Idx",
2425 			   "Device", "MCA",
2426 			   "SRC", "INC", "EXC");
2427 	} else {
2428 		seq_printf(seq,
2429 			   "%3d %6.6s 0x%08x "
2430 			   "0x%08x %6lu %6lu\n",
2431 			   state->dev->ifindex, state->dev->name,
2432 			   ntohl(state->im->multiaddr),
2433 			   ntohl(psf->sf_inaddr),
2434 			   psf->sf_count[MCAST_INCLUDE],
2435 			   psf->sf_count[MCAST_EXCLUDE]);
2436 	}
2437 	return 0;
2438 }
2439 
2440 static struct seq_operations igmp_mcf_seq_ops = {
2441 	.start	=	igmp_mcf_seq_start,
2442 	.next	=	igmp_mcf_seq_next,
2443 	.stop	=	igmp_mcf_seq_stop,
2444 	.show	=	igmp_mcf_seq_show,
2445 };
2446 
2447 static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2448 {
2449 	struct seq_file *seq;
2450 	int rc = -ENOMEM;
2451 	struct igmp_mcf_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL);
2452 
2453 	if (!s)
2454 		goto out;
2455 	rc = seq_open(file, &igmp_mcf_seq_ops);
2456 	if (rc)
2457 		goto out_kfree;
2458 
2459 	seq = file->private_data;
2460 	seq->private = s;
2461 	memset(s, 0, sizeof(*s));
2462 out:
2463 	return rc;
2464 out_kfree:
2465 	kfree(s);
2466 	goto out;
2467 }
2468 
2469 static struct file_operations igmp_mcf_seq_fops = {
2470 	.owner		=	THIS_MODULE,
2471 	.open		=	igmp_mcf_seq_open,
2472 	.read		=	seq_read,
2473 	.llseek		=	seq_lseek,
2474 	.release	=	seq_release_private,
2475 };
2476 
2477 int __init igmp_mc_proc_init(void)
2478 {
2479 	proc_net_fops_create("igmp", S_IRUGO, &igmp_mc_seq_fops);
2480 	proc_net_fops_create("mcfilter", S_IRUGO, &igmp_mcf_seq_fops);
2481 	return 0;
2482 }
2483 #endif
2484 
2485 EXPORT_SYMBOL(ip_mc_dec_group);
2486 EXPORT_SYMBOL(ip_mc_inc_group);
2487 EXPORT_SYMBOL(ip_mc_join_group);
2488