xref: /linux/net/ipv4/igmp.c (revision f24e9f586b377749dff37554696cf3a105540c94)
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, __u32 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, __u32 *pmca, int sfmode,
148 			 int sfcount, __u32 *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 		u32 *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(u32) +
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 		psrc = (u32 *)skb_put(skb, sizeof(u32));
459 		*psrc = psf->sf_inaddr;
460 		scount++; stotal++;
461 		if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
462 		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
463 			psf->sf_crcount--;
464 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
465 				if (psf_prev)
466 					psf_prev->sf_next = psf->sf_next;
467 				else
468 					*psf_list = psf->sf_next;
469 				kfree(psf);
470 				continue;
471 			}
472 		}
473 		psf_prev = psf;
474 	}
475 
476 empty_source:
477 	if (!stotal) {
478 		if (type == IGMPV3_ALLOW_NEW_SOURCES ||
479 		    type == IGMPV3_BLOCK_OLD_SOURCES)
480 			return skb;
481 		if (pmc->crcount || isquery) {
482 			/* make sure we have room for group header */
483 			if (skb && AVAILABLE(skb)<sizeof(struct igmpv3_grec)) {
484 				igmpv3_sendpack(skb);
485 				skb = NULL; /* add_grhead will get a new one */
486 			}
487 			skb = add_grhead(skb, pmc, type, &pgr);
488 		}
489 	}
490 	if (pgr)
491 		pgr->grec_nsrcs = htons(scount);
492 
493 	if (isquery)
494 		pmc->gsquery = 0;	/* clear query state on report */
495 	return skb;
496 }
497 
498 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
499 {
500 	struct sk_buff *skb = NULL;
501 	int type;
502 
503 	if (!pmc) {
504 		read_lock(&in_dev->mc_list_lock);
505 		for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
506 			if (pmc->multiaddr == IGMP_ALL_HOSTS)
507 				continue;
508 			spin_lock_bh(&pmc->lock);
509 			if (pmc->sfcount[MCAST_EXCLUDE])
510 				type = IGMPV3_MODE_IS_EXCLUDE;
511 			else
512 				type = IGMPV3_MODE_IS_INCLUDE;
513 			skb = add_grec(skb, pmc, type, 0, 0);
514 			spin_unlock_bh(&pmc->lock);
515 		}
516 		read_unlock(&in_dev->mc_list_lock);
517 	} else {
518 		spin_lock_bh(&pmc->lock);
519 		if (pmc->sfcount[MCAST_EXCLUDE])
520 			type = IGMPV3_MODE_IS_EXCLUDE;
521 		else
522 			type = IGMPV3_MODE_IS_INCLUDE;
523 		skb = add_grec(skb, pmc, type, 0, 0);
524 		spin_unlock_bh(&pmc->lock);
525 	}
526 	if (!skb)
527 		return 0;
528 	return igmpv3_sendpack(skb);
529 }
530 
531 /*
532  * remove zero-count source records from a source filter list
533  */
534 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
535 {
536 	struct ip_sf_list *psf_prev, *psf_next, *psf;
537 
538 	psf_prev = NULL;
539 	for (psf=*ppsf; psf; psf = psf_next) {
540 		psf_next = psf->sf_next;
541 		if (psf->sf_crcount == 0) {
542 			if (psf_prev)
543 				psf_prev->sf_next = psf->sf_next;
544 			else
545 				*ppsf = psf->sf_next;
546 			kfree(psf);
547 		} else
548 			psf_prev = psf;
549 	}
550 }
551 
552 static void igmpv3_send_cr(struct in_device *in_dev)
553 {
554 	struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
555 	struct sk_buff *skb = NULL;
556 	int type, dtype;
557 
558 	read_lock(&in_dev->mc_list_lock);
559 	spin_lock_bh(&in_dev->mc_tomb_lock);
560 
561 	/* deleted MCA's */
562 	pmc_prev = NULL;
563 	for (pmc=in_dev->mc_tomb; pmc; pmc=pmc_next) {
564 		pmc_next = pmc->next;
565 		if (pmc->sfmode == MCAST_INCLUDE) {
566 			type = IGMPV3_BLOCK_OLD_SOURCES;
567 			dtype = IGMPV3_BLOCK_OLD_SOURCES;
568 			skb = add_grec(skb, pmc, type, 1, 0);
569 			skb = add_grec(skb, pmc, dtype, 1, 1);
570 		}
571 		if (pmc->crcount) {
572 			if (pmc->sfmode == MCAST_EXCLUDE) {
573 				type = IGMPV3_CHANGE_TO_INCLUDE;
574 				skb = add_grec(skb, pmc, type, 1, 0);
575 			}
576 			pmc->crcount--;
577 			if (pmc->crcount == 0) {
578 				igmpv3_clear_zeros(&pmc->tomb);
579 				igmpv3_clear_zeros(&pmc->sources);
580 			}
581 		}
582 		if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
583 			if (pmc_prev)
584 				pmc_prev->next = pmc_next;
585 			else
586 				in_dev->mc_tomb = pmc_next;
587 			in_dev_put(pmc->interface);
588 			kfree(pmc);
589 		} else
590 			pmc_prev = pmc;
591 	}
592 	spin_unlock_bh(&in_dev->mc_tomb_lock);
593 
594 	/* change recs */
595 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
596 		spin_lock_bh(&pmc->lock);
597 		if (pmc->sfcount[MCAST_EXCLUDE]) {
598 			type = IGMPV3_BLOCK_OLD_SOURCES;
599 			dtype = IGMPV3_ALLOW_NEW_SOURCES;
600 		} else {
601 			type = IGMPV3_ALLOW_NEW_SOURCES;
602 			dtype = IGMPV3_BLOCK_OLD_SOURCES;
603 		}
604 		skb = add_grec(skb, pmc, type, 0, 0);
605 		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
606 
607 		/* filter mode changes */
608 		if (pmc->crcount) {
609 			if (pmc->sfmode == MCAST_EXCLUDE)
610 				type = IGMPV3_CHANGE_TO_EXCLUDE;
611 			else
612 				type = IGMPV3_CHANGE_TO_INCLUDE;
613 			skb = add_grec(skb, pmc, type, 0, 0);
614 			pmc->crcount--;
615 		}
616 		spin_unlock_bh(&pmc->lock);
617 	}
618 	read_unlock(&in_dev->mc_list_lock);
619 
620 	if (!skb)
621 		return;
622 	(void) igmpv3_sendpack(skb);
623 }
624 
625 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
626 	int type)
627 {
628 	struct sk_buff *skb;
629 	struct iphdr *iph;
630 	struct igmphdr *ih;
631 	struct rtable *rt;
632 	struct net_device *dev = in_dev->dev;
633 	u32	group = pmc ? pmc->multiaddr : 0;
634 	u32	dst;
635 
636 	if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
637 		return igmpv3_send_report(in_dev, pmc);
638 	else if (type == IGMP_HOST_LEAVE_MESSAGE)
639 		dst = IGMP_ALL_ROUTER;
640 	else
641 		dst = group;
642 
643 	{
644 		struct flowi fl = { .oif = dev->ifindex,
645 				    .nl_u = { .ip4_u = { .daddr = dst } },
646 				    .proto = IPPROTO_IGMP };
647 		if (ip_route_output_key(&rt, &fl))
648 			return -1;
649 	}
650 	if (rt->rt_src == 0) {
651 		ip_rt_put(rt);
652 		return -1;
653 	}
654 
655 	skb=alloc_skb(IGMP_SIZE+LL_RESERVED_SPACE(dev), GFP_ATOMIC);
656 	if (skb == NULL) {
657 		ip_rt_put(rt);
658 		return -1;
659 	}
660 
661 	skb->dst = &rt->u.dst;
662 
663 	skb_reserve(skb, LL_RESERVED_SPACE(dev));
664 
665 	skb->nh.iph = iph = (struct iphdr *)skb_put(skb, sizeof(struct iphdr)+4);
666 
667 	iph->version  = 4;
668 	iph->ihl      = (sizeof(struct iphdr)+4)>>2;
669 	iph->tos      = 0xc0;
670 	iph->frag_off = htons(IP_DF);
671 	iph->ttl      = 1;
672 	iph->daddr    = dst;
673 	iph->saddr    = rt->rt_src;
674 	iph->protocol = IPPROTO_IGMP;
675 	iph->tot_len  = htons(IGMP_SIZE);
676 	ip_select_ident(iph, &rt->u.dst, NULL);
677 	((u8*)&iph[1])[0] = IPOPT_RA;
678 	((u8*)&iph[1])[1] = 4;
679 	((u8*)&iph[1])[2] = 0;
680 	((u8*)&iph[1])[3] = 0;
681 	ip_send_check(iph);
682 
683 	ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
684 	ih->type=type;
685 	ih->code=0;
686 	ih->csum=0;
687 	ih->group=group;
688 	ih->csum=ip_compute_csum((void *)ih, sizeof(struct igmphdr));
689 
690 	return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, rt->u.dst.dev,
691 		       dst_output);
692 }
693 
694 static void igmp_gq_timer_expire(unsigned long data)
695 {
696 	struct in_device *in_dev = (struct in_device *)data;
697 
698 	in_dev->mr_gq_running = 0;
699 	igmpv3_send_report(in_dev, NULL);
700 	__in_dev_put(in_dev);
701 }
702 
703 static void igmp_ifc_timer_expire(unsigned long data)
704 {
705 	struct in_device *in_dev = (struct in_device *)data;
706 
707 	igmpv3_send_cr(in_dev);
708 	if (in_dev->mr_ifc_count) {
709 		in_dev->mr_ifc_count--;
710 		igmp_ifc_start_timer(in_dev, IGMP_Unsolicited_Report_Interval);
711 	}
712 	__in_dev_put(in_dev);
713 }
714 
715 static void igmp_ifc_event(struct in_device *in_dev)
716 {
717 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
718 		return;
719 	in_dev->mr_ifc_count = in_dev->mr_qrv ? in_dev->mr_qrv :
720 		IGMP_Unsolicited_Report_Count;
721 	igmp_ifc_start_timer(in_dev, 1);
722 }
723 
724 
725 static void igmp_timer_expire(unsigned long data)
726 {
727 	struct ip_mc_list *im=(struct ip_mc_list *)data;
728 	struct in_device *in_dev = im->interface;
729 
730 	spin_lock(&im->lock);
731 	im->tm_running=0;
732 
733 	if (im->unsolicit_count) {
734 		im->unsolicit_count--;
735 		igmp_start_timer(im, IGMP_Unsolicited_Report_Interval);
736 	}
737 	im->reporter = 1;
738 	spin_unlock(&im->lock);
739 
740 	if (IGMP_V1_SEEN(in_dev))
741 		igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
742 	else if (IGMP_V2_SEEN(in_dev))
743 		igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
744 	else
745 		igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
746 
747 	ip_ma_put(im);
748 }
749 
750 /* mark EXCLUDE-mode sources */
751 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __u32 *srcs)
752 {
753 	struct ip_sf_list *psf;
754 	int i, scount;
755 
756 	scount = 0;
757 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
758 		if (scount == nsrcs)
759 			break;
760 		for (i=0; i<nsrcs; i++) {
761 			/* skip inactive filters */
762 			if (pmc->sfcount[MCAST_INCLUDE] ||
763 			    pmc->sfcount[MCAST_EXCLUDE] !=
764 			    psf->sf_count[MCAST_EXCLUDE])
765 				continue;
766 			if (srcs[i] == psf->sf_inaddr) {
767 				scount++;
768 				break;
769 			}
770 		}
771 	}
772 	pmc->gsquery = 0;
773 	if (scount == nsrcs)	/* all sources excluded */
774 		return 0;
775 	return 1;
776 }
777 
778 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __u32 *srcs)
779 {
780 	struct ip_sf_list *psf;
781 	int i, scount;
782 
783 	if (pmc->sfmode == MCAST_EXCLUDE)
784 		return igmp_xmarksources(pmc, nsrcs, srcs);
785 
786 	/* mark INCLUDE-mode sources */
787 	scount = 0;
788 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
789 		if (scount == nsrcs)
790 			break;
791 		for (i=0; i<nsrcs; i++)
792 			if (srcs[i] == psf->sf_inaddr) {
793 				psf->sf_gsresp = 1;
794 				scount++;
795 				break;
796 			}
797 	}
798 	if (!scount) {
799 		pmc->gsquery = 0;
800 		return 0;
801 	}
802 	pmc->gsquery = 1;
803 	return 1;
804 }
805 
806 static void igmp_heard_report(struct in_device *in_dev, u32 group)
807 {
808 	struct ip_mc_list *im;
809 
810 	/* Timers are only set for non-local groups */
811 
812 	if (group == IGMP_ALL_HOSTS)
813 		return;
814 
815 	read_lock(&in_dev->mc_list_lock);
816 	for (im=in_dev->mc_list; im!=NULL; im=im->next) {
817 		if (im->multiaddr == group) {
818 			igmp_stop_timer(im);
819 			break;
820 		}
821 	}
822 	read_unlock(&in_dev->mc_list_lock);
823 }
824 
825 static void igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
826 	int len)
827 {
828 	struct igmphdr 		*ih = skb->h.igmph;
829 	struct igmpv3_query *ih3 = (struct igmpv3_query *)ih;
830 	struct ip_mc_list	*im;
831 	u32			group = ih->group;
832 	int			max_delay;
833 	int			mark = 0;
834 
835 
836 	if (len == 8) {
837 		if (ih->code == 0) {
838 			/* Alas, old v1 router presents here. */
839 
840 			max_delay = IGMP_Query_Response_Interval;
841 			in_dev->mr_v1_seen = jiffies +
842 				IGMP_V1_Router_Present_Timeout;
843 			group = 0;
844 		} else {
845 			/* v2 router present */
846 			max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
847 			in_dev->mr_v2_seen = jiffies +
848 				IGMP_V2_Router_Present_Timeout;
849 		}
850 		/* cancel the interface change timer */
851 		in_dev->mr_ifc_count = 0;
852 		if (del_timer(&in_dev->mr_ifc_timer))
853 			__in_dev_put(in_dev);
854 		/* clear deleted report items */
855 		igmpv3_clear_delrec(in_dev);
856 	} else if (len < 12) {
857 		return;	/* ignore bogus packet; freed by caller */
858 	} else { /* v3 */
859 		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
860 			return;
861 
862 		ih3 = (struct igmpv3_query *) skb->h.raw;
863 		if (ih3->nsrcs) {
864 			if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
865 					   + ntohs(ih3->nsrcs)*sizeof(__u32)))
866 				return;
867 			ih3 = (struct igmpv3_query *) skb->h.raw;
868 		}
869 
870 		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
871 		if (!max_delay)
872 			max_delay = 1;	/* can't mod w/ 0 */
873 		in_dev->mr_maxdelay = max_delay;
874 		if (ih3->qrv)
875 			in_dev->mr_qrv = ih3->qrv;
876 		if (!group) { /* general query */
877 			if (ih3->nsrcs)
878 				return;	/* no sources allowed */
879 			igmp_gq_start_timer(in_dev);
880 			return;
881 		}
882 		/* mark sources to include, if group & source-specific */
883 		mark = ih3->nsrcs != 0;
884 	}
885 
886 	/*
887 	 * - Start the timers in all of our membership records
888 	 *   that the query applies to for the interface on
889 	 *   which the query arrived excl. those that belong
890 	 *   to a "local" group (224.0.0.X)
891 	 * - For timers already running check if they need to
892 	 *   be reset.
893 	 * - Use the igmp->igmp_code field as the maximum
894 	 *   delay possible
895 	 */
896 	read_lock(&in_dev->mc_list_lock);
897 	for (im=in_dev->mc_list; im!=NULL; im=im->next) {
898 		int changed;
899 
900 		if (group && group != im->multiaddr)
901 			continue;
902 		if (im->multiaddr == IGMP_ALL_HOSTS)
903 			continue;
904 		spin_lock_bh(&im->lock);
905 		if (im->tm_running)
906 			im->gsquery = im->gsquery && mark;
907 		else
908 			im->gsquery = mark;
909 		changed = !im->gsquery ||
910 		    	igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
911 		spin_unlock_bh(&im->lock);
912 		if (changed)
913 			igmp_mod_timer(im, max_delay);
914 	}
915 	read_unlock(&in_dev->mc_list_lock);
916 }
917 
918 int igmp_rcv(struct sk_buff *skb)
919 {
920 	/* This basically follows the spec line by line -- see RFC1112 */
921 	struct igmphdr *ih;
922 	struct in_device *in_dev = in_dev_get(skb->dev);
923 	int len = skb->len;
924 
925 	if (in_dev==NULL) {
926 		kfree_skb(skb);
927 		return 0;
928 	}
929 
930 	if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
931 		goto drop;
932 
933 	switch (skb->ip_summed) {
934 	case CHECKSUM_HW:
935 		if (!(u16)csum_fold(skb->csum))
936 			break;
937 		/* fall through */
938 	case CHECKSUM_NONE:
939 		skb->csum = 0;
940 		if (__skb_checksum_complete(skb))
941 			goto drop;
942 	}
943 
944 	ih = skb->h.igmph;
945 	switch (ih->type) {
946 	case IGMP_HOST_MEMBERSHIP_QUERY:
947 		igmp_heard_query(in_dev, skb, len);
948 		break;
949 	case IGMP_HOST_MEMBERSHIP_REPORT:
950 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
951 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
952 		/* Is it our report looped back? */
953 		if (((struct rtable*)skb->dst)->fl.iif == 0)
954 			break;
955 		/* don't rely on MC router hearing unicast reports */
956 		if (skb->pkt_type == PACKET_MULTICAST ||
957 		    skb->pkt_type == PACKET_BROADCAST)
958 			igmp_heard_report(in_dev, ih->group);
959 		break;
960 	case IGMP_PIM:
961 #ifdef CONFIG_IP_PIMSM_V1
962 		in_dev_put(in_dev);
963 		return pim_rcv_v1(skb);
964 #endif
965 	case IGMP_DVMRP:
966 	case IGMP_TRACE:
967 	case IGMP_HOST_LEAVE_MESSAGE:
968 	case IGMP_MTRACE:
969 	case IGMP_MTRACE_RESP:
970 		break;
971 	default:
972 		break;
973 	}
974 
975 drop:
976 	in_dev_put(in_dev);
977 	kfree_skb(skb);
978 	return 0;
979 }
980 
981 #endif
982 
983 
984 /*
985  *	Add a filter to a device
986  */
987 
988 static void ip_mc_filter_add(struct in_device *in_dev, u32 addr)
989 {
990 	char buf[MAX_ADDR_LEN];
991 	struct net_device *dev = in_dev->dev;
992 
993 	/* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
994 	   We will get multicast token leakage, when IFF_MULTICAST
995 	   is changed. This check should be done in dev->set_multicast_list
996 	   routine. Something sort of:
997 	   if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
998 	   --ANK
999 	   */
1000 	if (arp_mc_map(addr, buf, dev, 0) == 0)
1001 		dev_mc_add(dev,buf,dev->addr_len,0);
1002 }
1003 
1004 /*
1005  *	Remove a filter from a device
1006  */
1007 
1008 static void ip_mc_filter_del(struct in_device *in_dev, u32 addr)
1009 {
1010 	char buf[MAX_ADDR_LEN];
1011 	struct net_device *dev = in_dev->dev;
1012 
1013 	if (arp_mc_map(addr, buf, dev, 0) == 0)
1014 		dev_mc_delete(dev,buf,dev->addr_len,0);
1015 }
1016 
1017 #ifdef CONFIG_IP_MULTICAST
1018 /*
1019  * deleted ip_mc_list manipulation
1020  */
1021 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1022 {
1023 	struct ip_mc_list *pmc;
1024 
1025 	/* this is an "ip_mc_list" for convenience; only the fields below
1026 	 * are actually used. In particular, the refcnt and users are not
1027 	 * used for management of the delete list. Using the same structure
1028 	 * for deleted items allows change reports to use common code with
1029 	 * non-deleted or query-response MCA's.
1030 	 */
1031 	pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
1032 	if (!pmc)
1033 		return;
1034 	spin_lock_bh(&im->lock);
1035 	pmc->interface = im->interface;
1036 	in_dev_hold(in_dev);
1037 	pmc->multiaddr = im->multiaddr;
1038 	pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1039 		IGMP_Unsolicited_Report_Count;
1040 	pmc->sfmode = im->sfmode;
1041 	if (pmc->sfmode == MCAST_INCLUDE) {
1042 		struct ip_sf_list *psf;
1043 
1044 		pmc->tomb = im->tomb;
1045 		pmc->sources = im->sources;
1046 		im->tomb = im->sources = NULL;
1047 		for (psf=pmc->sources; psf; psf=psf->sf_next)
1048 			psf->sf_crcount = pmc->crcount;
1049 	}
1050 	spin_unlock_bh(&im->lock);
1051 
1052 	spin_lock_bh(&in_dev->mc_tomb_lock);
1053 	pmc->next = in_dev->mc_tomb;
1054 	in_dev->mc_tomb = pmc;
1055 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1056 }
1057 
1058 static void igmpv3_del_delrec(struct in_device *in_dev, __u32 multiaddr)
1059 {
1060 	struct ip_mc_list *pmc, *pmc_prev;
1061 	struct ip_sf_list *psf, *psf_next;
1062 
1063 	spin_lock_bh(&in_dev->mc_tomb_lock);
1064 	pmc_prev = NULL;
1065 	for (pmc=in_dev->mc_tomb; pmc; pmc=pmc->next) {
1066 		if (pmc->multiaddr == multiaddr)
1067 			break;
1068 		pmc_prev = pmc;
1069 	}
1070 	if (pmc) {
1071 		if (pmc_prev)
1072 			pmc_prev->next = pmc->next;
1073 		else
1074 			in_dev->mc_tomb = pmc->next;
1075 	}
1076 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1077 	if (pmc) {
1078 		for (psf=pmc->tomb; psf; psf=psf_next) {
1079 			psf_next = psf->sf_next;
1080 			kfree(psf);
1081 		}
1082 		in_dev_put(pmc->interface);
1083 		kfree(pmc);
1084 	}
1085 }
1086 
1087 static void igmpv3_clear_delrec(struct in_device *in_dev)
1088 {
1089 	struct ip_mc_list *pmc, *nextpmc;
1090 
1091 	spin_lock_bh(&in_dev->mc_tomb_lock);
1092 	pmc = in_dev->mc_tomb;
1093 	in_dev->mc_tomb = NULL;
1094 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1095 
1096 	for (; pmc; pmc = nextpmc) {
1097 		nextpmc = pmc->next;
1098 		ip_mc_clear_src(pmc);
1099 		in_dev_put(pmc->interface);
1100 		kfree(pmc);
1101 	}
1102 	/* clear dead sources, too */
1103 	read_lock(&in_dev->mc_list_lock);
1104 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1105 		struct ip_sf_list *psf, *psf_next;
1106 
1107 		spin_lock_bh(&pmc->lock);
1108 		psf = pmc->tomb;
1109 		pmc->tomb = NULL;
1110 		spin_unlock_bh(&pmc->lock);
1111 		for (; psf; psf=psf_next) {
1112 			psf_next = psf->sf_next;
1113 			kfree(psf);
1114 		}
1115 	}
1116 	read_unlock(&in_dev->mc_list_lock);
1117 }
1118 #endif
1119 
1120 static void igmp_group_dropped(struct ip_mc_list *im)
1121 {
1122 	struct in_device *in_dev = im->interface;
1123 #ifdef CONFIG_IP_MULTICAST
1124 	int reporter;
1125 #endif
1126 
1127 	if (im->loaded) {
1128 		im->loaded = 0;
1129 		ip_mc_filter_del(in_dev, im->multiaddr);
1130 	}
1131 
1132 #ifdef CONFIG_IP_MULTICAST
1133 	if (im->multiaddr == IGMP_ALL_HOSTS)
1134 		return;
1135 
1136 	reporter = im->reporter;
1137 	igmp_stop_timer(im);
1138 
1139 	if (!in_dev->dead) {
1140 		if (IGMP_V1_SEEN(in_dev))
1141 			goto done;
1142 		if (IGMP_V2_SEEN(in_dev)) {
1143 			if (reporter)
1144 				igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1145 			goto done;
1146 		}
1147 		/* IGMPv3 */
1148 		igmpv3_add_delrec(in_dev, im);
1149 
1150 		igmp_ifc_event(in_dev);
1151 	}
1152 done:
1153 #endif
1154 	ip_mc_clear_src(im);
1155 }
1156 
1157 static void igmp_group_added(struct ip_mc_list *im)
1158 {
1159 	struct in_device *in_dev = im->interface;
1160 
1161 	if (im->loaded == 0) {
1162 		im->loaded = 1;
1163 		ip_mc_filter_add(in_dev, im->multiaddr);
1164 	}
1165 
1166 #ifdef CONFIG_IP_MULTICAST
1167 	if (im->multiaddr == IGMP_ALL_HOSTS)
1168 		return;
1169 
1170 	if (in_dev->dead)
1171 		return;
1172 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1173 		spin_lock_bh(&im->lock);
1174 		igmp_start_timer(im, IGMP_Initial_Report_Delay);
1175 		spin_unlock_bh(&im->lock);
1176 		return;
1177 	}
1178 	/* else, v3 */
1179 
1180 	im->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1181 		IGMP_Unsolicited_Report_Count;
1182 	igmp_ifc_event(in_dev);
1183 #endif
1184 }
1185 
1186 
1187 /*
1188  *	Multicast list managers
1189  */
1190 
1191 
1192 /*
1193  *	A socket has joined a multicast group on device dev.
1194  */
1195 
1196 void ip_mc_inc_group(struct in_device *in_dev, u32 addr)
1197 {
1198 	struct ip_mc_list *im;
1199 
1200 	ASSERT_RTNL();
1201 
1202 	for (im=in_dev->mc_list; im; im=im->next) {
1203 		if (im->multiaddr == addr) {
1204 			im->users++;
1205 			ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1206 			goto out;
1207 		}
1208 	}
1209 
1210 	im = kmalloc(sizeof(*im), GFP_KERNEL);
1211 	if (!im)
1212 		goto out;
1213 
1214 	im->users=1;
1215 	im->interface=in_dev;
1216 	in_dev_hold(in_dev);
1217 	im->multiaddr=addr;
1218 	/* initial mode is (EX, empty) */
1219 	im->sfmode = MCAST_EXCLUDE;
1220 	im->sfcount[MCAST_INCLUDE] = 0;
1221 	im->sfcount[MCAST_EXCLUDE] = 1;
1222 	im->sources = NULL;
1223 	im->tomb = NULL;
1224 	im->crcount = 0;
1225 	atomic_set(&im->refcnt, 1);
1226 	spin_lock_init(&im->lock);
1227 #ifdef CONFIG_IP_MULTICAST
1228 	im->tm_running=0;
1229 	init_timer(&im->timer);
1230 	im->timer.data=(unsigned long)im;
1231 	im->timer.function=&igmp_timer_expire;
1232 	im->unsolicit_count = IGMP_Unsolicited_Report_Count;
1233 	im->reporter = 0;
1234 	im->gsquery = 0;
1235 #endif
1236 	im->loaded = 0;
1237 	write_lock_bh(&in_dev->mc_list_lock);
1238 	im->next=in_dev->mc_list;
1239 	in_dev->mc_list=im;
1240 	write_unlock_bh(&in_dev->mc_list_lock);
1241 #ifdef CONFIG_IP_MULTICAST
1242 	igmpv3_del_delrec(in_dev, im->multiaddr);
1243 #endif
1244 	igmp_group_added(im);
1245 	if (!in_dev->dead)
1246 		ip_rt_multicast_event(in_dev);
1247 out:
1248 	return;
1249 }
1250 
1251 /*
1252  *	A socket has left a multicast group on device dev
1253  */
1254 
1255 void ip_mc_dec_group(struct in_device *in_dev, u32 addr)
1256 {
1257 	struct ip_mc_list *i, **ip;
1258 
1259 	ASSERT_RTNL();
1260 
1261 	for (ip=&in_dev->mc_list; (i=*ip)!=NULL; ip=&i->next) {
1262 		if (i->multiaddr==addr) {
1263 			if (--i->users == 0) {
1264 				write_lock_bh(&in_dev->mc_list_lock);
1265 				*ip = i->next;
1266 				write_unlock_bh(&in_dev->mc_list_lock);
1267 				igmp_group_dropped(i);
1268 
1269 				if (!in_dev->dead)
1270 					ip_rt_multicast_event(in_dev);
1271 
1272 				ip_ma_put(i);
1273 				return;
1274 			}
1275 			break;
1276 		}
1277 	}
1278 }
1279 
1280 /* Device going down */
1281 
1282 void ip_mc_down(struct in_device *in_dev)
1283 {
1284 	struct ip_mc_list *i;
1285 
1286 	ASSERT_RTNL();
1287 
1288 	for (i=in_dev->mc_list; i; i=i->next)
1289 		igmp_group_dropped(i);
1290 
1291 #ifdef CONFIG_IP_MULTICAST
1292 	in_dev->mr_ifc_count = 0;
1293 	if (del_timer(&in_dev->mr_ifc_timer))
1294 		__in_dev_put(in_dev);
1295 	in_dev->mr_gq_running = 0;
1296 	if (del_timer(&in_dev->mr_gq_timer))
1297 		__in_dev_put(in_dev);
1298 	igmpv3_clear_delrec(in_dev);
1299 #endif
1300 
1301 	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1302 }
1303 
1304 void ip_mc_init_dev(struct in_device *in_dev)
1305 {
1306 	ASSERT_RTNL();
1307 
1308 	in_dev->mc_tomb = NULL;
1309 #ifdef CONFIG_IP_MULTICAST
1310 	in_dev->mr_gq_running = 0;
1311 	init_timer(&in_dev->mr_gq_timer);
1312 	in_dev->mr_gq_timer.data=(unsigned long) in_dev;
1313 	in_dev->mr_gq_timer.function=&igmp_gq_timer_expire;
1314 	in_dev->mr_ifc_count = 0;
1315 	init_timer(&in_dev->mr_ifc_timer);
1316 	in_dev->mr_ifc_timer.data=(unsigned long) in_dev;
1317 	in_dev->mr_ifc_timer.function=&igmp_ifc_timer_expire;
1318 	in_dev->mr_qrv = IGMP_Unsolicited_Report_Count;
1319 #endif
1320 
1321 	rwlock_init(&in_dev->mc_list_lock);
1322 	spin_lock_init(&in_dev->mc_tomb_lock);
1323 }
1324 
1325 /* Device going up */
1326 
1327 void ip_mc_up(struct in_device *in_dev)
1328 {
1329 	struct ip_mc_list *i;
1330 
1331 	ASSERT_RTNL();
1332 
1333 	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1334 
1335 	for (i=in_dev->mc_list; i; i=i->next)
1336 		igmp_group_added(i);
1337 }
1338 
1339 /*
1340  *	Device is about to be destroyed: clean up.
1341  */
1342 
1343 void ip_mc_destroy_dev(struct in_device *in_dev)
1344 {
1345 	struct ip_mc_list *i;
1346 
1347 	ASSERT_RTNL();
1348 
1349 	/* Deactivate timers */
1350 	ip_mc_down(in_dev);
1351 
1352 	write_lock_bh(&in_dev->mc_list_lock);
1353 	while ((i = in_dev->mc_list) != NULL) {
1354 		in_dev->mc_list = i->next;
1355 		write_unlock_bh(&in_dev->mc_list_lock);
1356 
1357 		igmp_group_dropped(i);
1358 		ip_ma_put(i);
1359 
1360 		write_lock_bh(&in_dev->mc_list_lock);
1361 	}
1362 	write_unlock_bh(&in_dev->mc_list_lock);
1363 }
1364 
1365 static struct in_device * ip_mc_find_dev(struct ip_mreqn *imr)
1366 {
1367 	struct flowi fl = { .nl_u = { .ip4_u =
1368 				      { .daddr = imr->imr_multiaddr.s_addr } } };
1369 	struct rtable *rt;
1370 	struct net_device *dev = NULL;
1371 	struct in_device *idev = NULL;
1372 
1373 	if (imr->imr_ifindex) {
1374 		idev = inetdev_by_index(imr->imr_ifindex);
1375 		if (idev)
1376 			__in_dev_put(idev);
1377 		return idev;
1378 	}
1379 	if (imr->imr_address.s_addr) {
1380 		dev = ip_dev_find(imr->imr_address.s_addr);
1381 		if (!dev)
1382 			return NULL;
1383 		dev_put(dev);
1384 	}
1385 
1386 	if (!dev && !ip_route_output_key(&rt, &fl)) {
1387 		dev = rt->u.dst.dev;
1388 		ip_rt_put(rt);
1389 	}
1390 	if (dev) {
1391 		imr->imr_ifindex = dev->ifindex;
1392 		idev = __in_dev_get_rtnl(dev);
1393 	}
1394 	return idev;
1395 }
1396 
1397 /*
1398  *	Join a socket to a group
1399  */
1400 int sysctl_igmp_max_memberships = IP_MAX_MEMBERSHIPS;
1401 int sysctl_igmp_max_msf = IP_MAX_MSF;
1402 
1403 
1404 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1405 	__u32 *psfsrc)
1406 {
1407 	struct ip_sf_list *psf, *psf_prev;
1408 	int rv = 0;
1409 
1410 	psf_prev = NULL;
1411 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1412 		if (psf->sf_inaddr == *psfsrc)
1413 			break;
1414 		psf_prev = psf;
1415 	}
1416 	if (!psf || psf->sf_count[sfmode] == 0) {
1417 		/* source filter not found, or count wrong =>  bug */
1418 		return -ESRCH;
1419 	}
1420 	psf->sf_count[sfmode]--;
1421 	if (psf->sf_count[sfmode] == 0) {
1422 		ip_rt_multicast_event(pmc->interface);
1423 	}
1424 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1425 #ifdef CONFIG_IP_MULTICAST
1426 		struct in_device *in_dev = pmc->interface;
1427 #endif
1428 
1429 		/* no more filters for this source */
1430 		if (psf_prev)
1431 			psf_prev->sf_next = psf->sf_next;
1432 		else
1433 			pmc->sources = psf->sf_next;
1434 #ifdef CONFIG_IP_MULTICAST
1435 		if (psf->sf_oldin &&
1436 		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1437 			psf->sf_crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1438 				IGMP_Unsolicited_Report_Count;
1439 			psf->sf_next = pmc->tomb;
1440 			pmc->tomb = psf;
1441 			rv = 1;
1442 		} else
1443 #endif
1444 			kfree(psf);
1445 	}
1446 	return rv;
1447 }
1448 
1449 #ifndef CONFIG_IP_MULTICAST
1450 #define igmp_ifc_event(x)	do { } while (0)
1451 #endif
1452 
1453 static int ip_mc_del_src(struct in_device *in_dev, __u32 *pmca, int sfmode,
1454 			 int sfcount, __u32 *psfsrc, int delta)
1455 {
1456 	struct ip_mc_list *pmc;
1457 	int	changerec = 0;
1458 	int	i, err;
1459 
1460 	if (!in_dev)
1461 		return -ENODEV;
1462 	read_lock(&in_dev->mc_list_lock);
1463 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1464 		if (*pmca == pmc->multiaddr)
1465 			break;
1466 	}
1467 	if (!pmc) {
1468 		/* MCA not found?? bug */
1469 		read_unlock(&in_dev->mc_list_lock);
1470 		return -ESRCH;
1471 	}
1472 	spin_lock_bh(&pmc->lock);
1473 	read_unlock(&in_dev->mc_list_lock);
1474 #ifdef CONFIG_IP_MULTICAST
1475 	sf_markstate(pmc);
1476 #endif
1477 	if (!delta) {
1478 		err = -EINVAL;
1479 		if (!pmc->sfcount[sfmode])
1480 			goto out_unlock;
1481 		pmc->sfcount[sfmode]--;
1482 	}
1483 	err = 0;
1484 	for (i=0; i<sfcount; i++) {
1485 		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1486 
1487 		changerec |= rv > 0;
1488 		if (!err && rv < 0)
1489 			err = rv;
1490 	}
1491 	if (pmc->sfmode == MCAST_EXCLUDE &&
1492 	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1493 	    pmc->sfcount[MCAST_INCLUDE]) {
1494 #ifdef CONFIG_IP_MULTICAST
1495 		struct ip_sf_list *psf;
1496 #endif
1497 
1498 		/* filter mode change */
1499 		pmc->sfmode = MCAST_INCLUDE;
1500 #ifdef CONFIG_IP_MULTICAST
1501 		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1502 			IGMP_Unsolicited_Report_Count;
1503 		in_dev->mr_ifc_count = pmc->crcount;
1504 		for (psf=pmc->sources; psf; psf = psf->sf_next)
1505 			psf->sf_crcount = 0;
1506 		igmp_ifc_event(pmc->interface);
1507 	} else if (sf_setstate(pmc) || changerec) {
1508 		igmp_ifc_event(pmc->interface);
1509 #endif
1510 	}
1511 out_unlock:
1512 	spin_unlock_bh(&pmc->lock);
1513 	return err;
1514 }
1515 
1516 /*
1517  * Add multicast single-source filter to the interface list
1518  */
1519 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1520 	__u32 *psfsrc, int delta)
1521 {
1522 	struct ip_sf_list *psf, *psf_prev;
1523 
1524 	psf_prev = NULL;
1525 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1526 		if (psf->sf_inaddr == *psfsrc)
1527 			break;
1528 		psf_prev = psf;
1529 	}
1530 	if (!psf) {
1531 		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1532 		if (!psf)
1533 			return -ENOBUFS;
1534 		psf->sf_inaddr = *psfsrc;
1535 		if (psf_prev) {
1536 			psf_prev->sf_next = psf;
1537 		} else
1538 			pmc->sources = psf;
1539 	}
1540 	psf->sf_count[sfmode]++;
1541 	if (psf->sf_count[sfmode] == 1) {
1542 		ip_rt_multicast_event(pmc->interface);
1543 	}
1544 	return 0;
1545 }
1546 
1547 #ifdef CONFIG_IP_MULTICAST
1548 static void sf_markstate(struct ip_mc_list *pmc)
1549 {
1550 	struct ip_sf_list *psf;
1551 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1552 
1553 	for (psf=pmc->sources; psf; psf=psf->sf_next)
1554 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1555 			psf->sf_oldin = mca_xcount ==
1556 				psf->sf_count[MCAST_EXCLUDE] &&
1557 				!psf->sf_count[MCAST_INCLUDE];
1558 		} else
1559 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1560 }
1561 
1562 static int sf_setstate(struct ip_mc_list *pmc)
1563 {
1564 	struct ip_sf_list *psf, *dpsf;
1565 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1566 	int qrv = pmc->interface->mr_qrv;
1567 	int new_in, rv;
1568 
1569 	rv = 0;
1570 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1571 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1572 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1573 				!psf->sf_count[MCAST_INCLUDE];
1574 		} else
1575 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1576 		if (new_in) {
1577 			if (!psf->sf_oldin) {
1578 				struct ip_sf_list *prev = NULL;
1579 
1580 				for (dpsf=pmc->tomb; dpsf; dpsf=dpsf->sf_next) {
1581 					if (dpsf->sf_inaddr == psf->sf_inaddr)
1582 						break;
1583 					prev = dpsf;
1584 				}
1585 				if (dpsf) {
1586 					if (prev)
1587 						prev->sf_next = dpsf->sf_next;
1588 					else
1589 						pmc->tomb = dpsf->sf_next;
1590 					kfree(dpsf);
1591 				}
1592 				psf->sf_crcount = qrv;
1593 				rv++;
1594 			}
1595 		} else if (psf->sf_oldin) {
1596 
1597 			psf->sf_crcount = 0;
1598 			/*
1599 			 * add or update "delete" records if an active filter
1600 			 * is now inactive
1601 			 */
1602 			for (dpsf=pmc->tomb; dpsf; dpsf=dpsf->sf_next)
1603 				if (dpsf->sf_inaddr == psf->sf_inaddr)
1604 					break;
1605 			if (!dpsf) {
1606 				dpsf = (struct ip_sf_list *)
1607 					kmalloc(sizeof(*dpsf), GFP_ATOMIC);
1608 				if (!dpsf)
1609 					continue;
1610 				*dpsf = *psf;
1611 				/* pmc->lock held by callers */
1612 				dpsf->sf_next = pmc->tomb;
1613 				pmc->tomb = dpsf;
1614 			}
1615 			dpsf->sf_crcount = qrv;
1616 			rv++;
1617 		}
1618 	}
1619 	return rv;
1620 }
1621 #endif
1622 
1623 /*
1624  * Add multicast source filter list to the interface list
1625  */
1626 static int ip_mc_add_src(struct in_device *in_dev, __u32 *pmca, int sfmode,
1627 			 int sfcount, __u32 *psfsrc, int delta)
1628 {
1629 	struct ip_mc_list *pmc;
1630 	int	isexclude;
1631 	int	i, err;
1632 
1633 	if (!in_dev)
1634 		return -ENODEV;
1635 	read_lock(&in_dev->mc_list_lock);
1636 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1637 		if (*pmca == pmc->multiaddr)
1638 			break;
1639 	}
1640 	if (!pmc) {
1641 		/* MCA not found?? bug */
1642 		read_unlock(&in_dev->mc_list_lock);
1643 		return -ESRCH;
1644 	}
1645 	spin_lock_bh(&pmc->lock);
1646 	read_unlock(&in_dev->mc_list_lock);
1647 
1648 #ifdef CONFIG_IP_MULTICAST
1649 	sf_markstate(pmc);
1650 #endif
1651 	isexclude = pmc->sfmode == MCAST_EXCLUDE;
1652 	if (!delta)
1653 		pmc->sfcount[sfmode]++;
1654 	err = 0;
1655 	for (i=0; i<sfcount; i++) {
1656 		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i], delta);
1657 		if (err)
1658 			break;
1659 	}
1660 	if (err) {
1661 		int j;
1662 
1663 		pmc->sfcount[sfmode]--;
1664 		for (j=0; j<i; j++)
1665 			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1666 	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
1667 #ifdef CONFIG_IP_MULTICAST
1668 		struct in_device *in_dev = pmc->interface;
1669 		struct ip_sf_list *psf;
1670 #endif
1671 
1672 		/* filter mode change */
1673 		if (pmc->sfcount[MCAST_EXCLUDE])
1674 			pmc->sfmode = MCAST_EXCLUDE;
1675 		else if (pmc->sfcount[MCAST_INCLUDE])
1676 			pmc->sfmode = MCAST_INCLUDE;
1677 #ifdef CONFIG_IP_MULTICAST
1678 		/* else no filters; keep old mode for reports */
1679 
1680 		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1681 			IGMP_Unsolicited_Report_Count;
1682 		in_dev->mr_ifc_count = pmc->crcount;
1683 		for (psf=pmc->sources; psf; psf = psf->sf_next)
1684 			psf->sf_crcount = 0;
1685 		igmp_ifc_event(in_dev);
1686 	} else if (sf_setstate(pmc)) {
1687 		igmp_ifc_event(in_dev);
1688 #endif
1689 	}
1690 	spin_unlock_bh(&pmc->lock);
1691 	return err;
1692 }
1693 
1694 static void ip_mc_clear_src(struct ip_mc_list *pmc)
1695 {
1696 	struct ip_sf_list *psf, *nextpsf;
1697 
1698 	for (psf=pmc->tomb; psf; psf=nextpsf) {
1699 		nextpsf = psf->sf_next;
1700 		kfree(psf);
1701 	}
1702 	pmc->tomb = NULL;
1703 	for (psf=pmc->sources; psf; psf=nextpsf) {
1704 		nextpsf = psf->sf_next;
1705 		kfree(psf);
1706 	}
1707 	pmc->sources = NULL;
1708 	pmc->sfmode = MCAST_EXCLUDE;
1709 	pmc->sfcount[MCAST_INCLUDE] = 0;
1710 	pmc->sfcount[MCAST_EXCLUDE] = 1;
1711 }
1712 
1713 
1714 /*
1715  * Join a multicast group
1716  */
1717 int ip_mc_join_group(struct sock *sk , struct ip_mreqn *imr)
1718 {
1719 	int err;
1720 	u32 addr = imr->imr_multiaddr.s_addr;
1721 	struct ip_mc_socklist *iml=NULL, *i;
1722 	struct in_device *in_dev;
1723 	struct inet_sock *inet = inet_sk(sk);
1724 	int ifindex;
1725 	int count = 0;
1726 
1727 	if (!MULTICAST(addr))
1728 		return -EINVAL;
1729 
1730 	rtnl_lock();
1731 
1732 	in_dev = ip_mc_find_dev(imr);
1733 
1734 	if (!in_dev) {
1735 		iml = NULL;
1736 		err = -ENODEV;
1737 		goto done;
1738 	}
1739 
1740 	err = -EADDRINUSE;
1741 	ifindex = imr->imr_ifindex;
1742 	for (i = inet->mc_list; i; i = i->next) {
1743 		if (i->multi.imr_multiaddr.s_addr == addr &&
1744 		    i->multi.imr_ifindex == ifindex)
1745 			goto done;
1746 		count++;
1747 	}
1748 	err = -ENOBUFS;
1749 	if (count >= sysctl_igmp_max_memberships)
1750 		goto done;
1751 	iml = sock_kmalloc(sk,sizeof(*iml),GFP_KERNEL);
1752 	if (iml == NULL)
1753 		goto done;
1754 
1755 	memcpy(&iml->multi, imr, sizeof(*imr));
1756 	iml->next = inet->mc_list;
1757 	iml->sflist = NULL;
1758 	iml->sfmode = MCAST_EXCLUDE;
1759 	inet->mc_list = iml;
1760 	ip_mc_inc_group(in_dev, addr);
1761 	err = 0;
1762 done:
1763 	rtnl_unlock();
1764 	return err;
1765 }
1766 
1767 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
1768 			   struct in_device *in_dev)
1769 {
1770 	int err;
1771 
1772 	if (iml->sflist == 0) {
1773 		/* any-source empty exclude case */
1774 		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1775 			iml->sfmode, 0, NULL, 0);
1776 	}
1777 	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1778 			iml->sfmode, iml->sflist->sl_count,
1779 			iml->sflist->sl_addr, 0);
1780 	sock_kfree_s(sk, iml->sflist, IP_SFLSIZE(iml->sflist->sl_max));
1781 	iml->sflist = NULL;
1782 	return err;
1783 }
1784 
1785 /*
1786  *	Ask a socket to leave a group.
1787  */
1788 
1789 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
1790 {
1791 	struct inet_sock *inet = inet_sk(sk);
1792 	struct ip_mc_socklist *iml, **imlp;
1793 	struct in_device *in_dev;
1794 	u32 group = imr->imr_multiaddr.s_addr;
1795 	u32 ifindex;
1796 	int ret = -EADDRNOTAVAIL;
1797 
1798 	rtnl_lock();
1799 	in_dev = ip_mc_find_dev(imr);
1800 	ifindex = imr->imr_ifindex;
1801 	for (imlp = &inet->mc_list; (iml = *imlp) != NULL; imlp = &iml->next) {
1802 		if (iml->multi.imr_multiaddr.s_addr != group)
1803 			continue;
1804 		if (ifindex) {
1805 			if (iml->multi.imr_ifindex != ifindex)
1806 				continue;
1807 		} else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
1808 				iml->multi.imr_address.s_addr)
1809 			continue;
1810 
1811 		(void) ip_mc_leave_src(sk, iml, in_dev);
1812 
1813 		*imlp = iml->next;
1814 
1815 		if (in_dev)
1816 			ip_mc_dec_group(in_dev, group);
1817 		rtnl_unlock();
1818 		sock_kfree_s(sk, iml, sizeof(*iml));
1819 		return 0;
1820 	}
1821 	if (!in_dev)
1822 		ret = -ENODEV;
1823 	rtnl_unlock();
1824 	return ret;
1825 }
1826 
1827 int ip_mc_source(int add, int omode, struct sock *sk, struct
1828 	ip_mreq_source *mreqs, int ifindex)
1829 {
1830 	int err;
1831 	struct ip_mreqn imr;
1832 	u32 addr = mreqs->imr_multiaddr;
1833 	struct ip_mc_socklist *pmc;
1834 	struct in_device *in_dev = NULL;
1835 	struct inet_sock *inet = inet_sk(sk);
1836 	struct ip_sf_socklist *psl;
1837 	int leavegroup = 0;
1838 	int i, j, rv;
1839 
1840 	if (!MULTICAST(addr))
1841 		return -EINVAL;
1842 
1843 	rtnl_lock();
1844 
1845 	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
1846 	imr.imr_address.s_addr = mreqs->imr_interface;
1847 	imr.imr_ifindex = ifindex;
1848 	in_dev = ip_mc_find_dev(&imr);
1849 
1850 	if (!in_dev) {
1851 		err = -ENODEV;
1852 		goto done;
1853 	}
1854 	err = -EADDRNOTAVAIL;
1855 
1856 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
1857 		if (pmc->multi.imr_multiaddr.s_addr == imr.imr_multiaddr.s_addr
1858 		    && pmc->multi.imr_ifindex == imr.imr_ifindex)
1859 			break;
1860 	}
1861 	if (!pmc) {		/* must have a prior join */
1862 		err = -EINVAL;
1863 		goto done;
1864 	}
1865 	/* if a source filter was set, must be the same mode as before */
1866 	if (pmc->sflist) {
1867 		if (pmc->sfmode != omode) {
1868 			err = -EINVAL;
1869 			goto done;
1870 		}
1871 	} else if (pmc->sfmode != omode) {
1872 		/* allow mode switches for empty-set filters */
1873 		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
1874 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
1875 			NULL, 0);
1876 		pmc->sfmode = omode;
1877 	}
1878 
1879 	psl = pmc->sflist;
1880 	if (!add) {
1881 		if (!psl)
1882 			goto done;	/* err = -EADDRNOTAVAIL */
1883 		rv = !0;
1884 		for (i=0; i<psl->sl_count; i++) {
1885 			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1886 				sizeof(__u32));
1887 			if (rv == 0)
1888 				break;
1889 		}
1890 		if (rv)		/* source not found */
1891 			goto done;	/* err = -EADDRNOTAVAIL */
1892 
1893 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
1894 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
1895 			leavegroup = 1;
1896 			goto done;
1897 		}
1898 
1899 		/* update the interface filter */
1900 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1901 			&mreqs->imr_sourceaddr, 1);
1902 
1903 		for (j=i+1; j<psl->sl_count; j++)
1904 			psl->sl_addr[j-1] = psl->sl_addr[j];
1905 		psl->sl_count--;
1906 		err = 0;
1907 		goto done;
1908 	}
1909 	/* else, add a new source to the filter */
1910 
1911 	if (psl && psl->sl_count >= sysctl_igmp_max_msf) {
1912 		err = -ENOBUFS;
1913 		goto done;
1914 	}
1915 	if (!psl || psl->sl_count == psl->sl_max) {
1916 		struct ip_sf_socklist *newpsl;
1917 		int count = IP_SFBLOCK;
1918 
1919 		if (psl)
1920 			count += psl->sl_max;
1921 		newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
1922 		if (!newpsl) {
1923 			err = -ENOBUFS;
1924 			goto done;
1925 		}
1926 		newpsl->sl_max = count;
1927 		newpsl->sl_count = count - IP_SFBLOCK;
1928 		if (psl) {
1929 			for (i=0; i<psl->sl_count; i++)
1930 				newpsl->sl_addr[i] = psl->sl_addr[i];
1931 			sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
1932 		}
1933 		pmc->sflist = psl = newpsl;
1934 	}
1935 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
1936 	for (i=0; i<psl->sl_count; i++) {
1937 		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1938 			sizeof(__u32));
1939 		if (rv == 0)
1940 			break;
1941 	}
1942 	if (rv == 0)		/* address already there is an error */
1943 		goto done;
1944 	for (j=psl->sl_count-1; j>=i; j--)
1945 		psl->sl_addr[j+1] = psl->sl_addr[j];
1946 	psl->sl_addr[i] = mreqs->imr_sourceaddr;
1947 	psl->sl_count++;
1948 	err = 0;
1949 	/* update the interface list */
1950 	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1951 		&mreqs->imr_sourceaddr, 1);
1952 done:
1953 	rtnl_unlock();
1954 	if (leavegroup)
1955 		return ip_mc_leave_group(sk, &imr);
1956 	return err;
1957 }
1958 
1959 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
1960 {
1961 	int err = 0;
1962 	struct ip_mreqn	imr;
1963 	u32 addr = msf->imsf_multiaddr;
1964 	struct ip_mc_socklist *pmc;
1965 	struct in_device *in_dev;
1966 	struct inet_sock *inet = inet_sk(sk);
1967 	struct ip_sf_socklist *newpsl, *psl;
1968 	int leavegroup = 0;
1969 
1970 	if (!MULTICAST(addr))
1971 		return -EINVAL;
1972 	if (msf->imsf_fmode != MCAST_INCLUDE &&
1973 	    msf->imsf_fmode != MCAST_EXCLUDE)
1974 		return -EINVAL;
1975 
1976 	rtnl_lock();
1977 
1978 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
1979 	imr.imr_address.s_addr = msf->imsf_interface;
1980 	imr.imr_ifindex = ifindex;
1981 	in_dev = ip_mc_find_dev(&imr);
1982 
1983 	if (!in_dev) {
1984 		err = -ENODEV;
1985 		goto done;
1986 	}
1987 
1988 	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
1989 	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
1990 		leavegroup = 1;
1991 		goto done;
1992 	}
1993 
1994 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
1995 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
1996 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
1997 			break;
1998 	}
1999 	if (!pmc) {		/* must have a prior join */
2000 		err = -EINVAL;
2001 		goto done;
2002 	}
2003 	if (msf->imsf_numsrc) {
2004 		newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2005 							   GFP_KERNEL);
2006 		if (!newpsl) {
2007 			err = -ENOBUFS;
2008 			goto done;
2009 		}
2010 		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2011 		memcpy(newpsl->sl_addr, msf->imsf_slist,
2012 			msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2013 		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2014 			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2015 		if (err) {
2016 			sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2017 			goto done;
2018 		}
2019 	} else {
2020 		newpsl = NULL;
2021 		(void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2022 				     msf->imsf_fmode, 0, NULL, 0);
2023 	}
2024 	psl = pmc->sflist;
2025 	if (psl) {
2026 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2027 			psl->sl_count, psl->sl_addr, 0);
2028 		sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
2029 	} else
2030 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2031 			0, NULL, 0);
2032 	pmc->sflist = newpsl;
2033 	pmc->sfmode = msf->imsf_fmode;
2034 	err = 0;
2035 done:
2036 	rtnl_unlock();
2037 	if (leavegroup)
2038 		err = ip_mc_leave_group(sk, &imr);
2039 	return err;
2040 }
2041 
2042 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2043 	struct ip_msfilter __user *optval, int __user *optlen)
2044 {
2045 	int err, len, count, copycount;
2046 	struct ip_mreqn	imr;
2047 	u32 addr = msf->imsf_multiaddr;
2048 	struct ip_mc_socklist *pmc;
2049 	struct in_device *in_dev;
2050 	struct inet_sock *inet = inet_sk(sk);
2051 	struct ip_sf_socklist *psl;
2052 
2053 	if (!MULTICAST(addr))
2054 		return -EINVAL;
2055 
2056 	rtnl_lock();
2057 
2058 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2059 	imr.imr_address.s_addr = msf->imsf_interface;
2060 	imr.imr_ifindex = 0;
2061 	in_dev = ip_mc_find_dev(&imr);
2062 
2063 	if (!in_dev) {
2064 		err = -ENODEV;
2065 		goto done;
2066 	}
2067 	err = -EADDRNOTAVAIL;
2068 
2069 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2070 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2071 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2072 			break;
2073 	}
2074 	if (!pmc)		/* must have a prior join */
2075 		goto done;
2076 	msf->imsf_fmode = pmc->sfmode;
2077 	psl = pmc->sflist;
2078 	rtnl_unlock();
2079 	if (!psl) {
2080 		len = 0;
2081 		count = 0;
2082 	} else {
2083 		count = psl->sl_count;
2084 	}
2085 	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2086 	len = copycount * sizeof(psl->sl_addr[0]);
2087 	msf->imsf_numsrc = count;
2088 	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2089 	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2090 		return -EFAULT;
2091 	}
2092 	if (len &&
2093 	    copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2094 		return -EFAULT;
2095 	return 0;
2096 done:
2097 	rtnl_unlock();
2098 	return err;
2099 }
2100 
2101 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2102 	struct group_filter __user *optval, int __user *optlen)
2103 {
2104 	int err, i, count, copycount;
2105 	struct sockaddr_in *psin;
2106 	u32 addr;
2107 	struct ip_mc_socklist *pmc;
2108 	struct inet_sock *inet = inet_sk(sk);
2109 	struct ip_sf_socklist *psl;
2110 
2111 	psin = (struct sockaddr_in *)&gsf->gf_group;
2112 	if (psin->sin_family != AF_INET)
2113 		return -EINVAL;
2114 	addr = psin->sin_addr.s_addr;
2115 	if (!MULTICAST(addr))
2116 		return -EINVAL;
2117 
2118 	rtnl_lock();
2119 
2120 	err = -EADDRNOTAVAIL;
2121 
2122 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2123 		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2124 		    pmc->multi.imr_ifindex == gsf->gf_interface)
2125 			break;
2126 	}
2127 	if (!pmc)		/* must have a prior join */
2128 		goto done;
2129 	gsf->gf_fmode = pmc->sfmode;
2130 	psl = pmc->sflist;
2131 	rtnl_unlock();
2132 	count = psl ? psl->sl_count : 0;
2133 	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2134 	gsf->gf_numsrc = count;
2135 	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2136 	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2137 		return -EFAULT;
2138 	}
2139 	for (i=0; i<copycount; i++) {
2140 		struct sockaddr_in *psin;
2141 		struct sockaddr_storage ss;
2142 
2143 		psin = (struct sockaddr_in *)&ss;
2144 		memset(&ss, 0, sizeof(ss));
2145 		psin->sin_family = AF_INET;
2146 		psin->sin_addr.s_addr = psl->sl_addr[i];
2147 		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2148 			return -EFAULT;
2149 	}
2150 	return 0;
2151 done:
2152 	rtnl_unlock();
2153 	return err;
2154 }
2155 
2156 /*
2157  * check if a multicast source filter allows delivery for a given <src,dst,intf>
2158  */
2159 int ip_mc_sf_allow(struct sock *sk, u32 loc_addr, u32 rmt_addr, int dif)
2160 {
2161 	struct inet_sock *inet = inet_sk(sk);
2162 	struct ip_mc_socklist *pmc;
2163 	struct ip_sf_socklist *psl;
2164 	int i;
2165 
2166 	if (!MULTICAST(loc_addr))
2167 		return 1;
2168 
2169 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2170 		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2171 		    pmc->multi.imr_ifindex == dif)
2172 			break;
2173 	}
2174 	if (!pmc)
2175 		return 1;
2176 	psl = pmc->sflist;
2177 	if (!psl)
2178 		return pmc->sfmode == MCAST_EXCLUDE;
2179 
2180 	for (i=0; i<psl->sl_count; i++) {
2181 		if (psl->sl_addr[i] == rmt_addr)
2182 			break;
2183 	}
2184 	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2185 		return 0;
2186 	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2187 		return 0;
2188 	return 1;
2189 }
2190 
2191 /*
2192  *	A socket is closing.
2193  */
2194 
2195 void ip_mc_drop_socket(struct sock *sk)
2196 {
2197 	struct inet_sock *inet = inet_sk(sk);
2198 	struct ip_mc_socklist *iml;
2199 
2200 	if (inet->mc_list == NULL)
2201 		return;
2202 
2203 	rtnl_lock();
2204 	while ((iml = inet->mc_list) != NULL) {
2205 		struct in_device *in_dev;
2206 		inet->mc_list = iml->next;
2207 
2208 		in_dev = inetdev_by_index(iml->multi.imr_ifindex);
2209 		(void) ip_mc_leave_src(sk, iml, in_dev);
2210 		if (in_dev != NULL) {
2211 			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2212 			in_dev_put(in_dev);
2213 		}
2214 		sock_kfree_s(sk, iml, sizeof(*iml));
2215 	}
2216 	rtnl_unlock();
2217 }
2218 
2219 int ip_check_mc(struct in_device *in_dev, u32 mc_addr, u32 src_addr, u16 proto)
2220 {
2221 	struct ip_mc_list *im;
2222 	struct ip_sf_list *psf;
2223 	int rv = 0;
2224 
2225 	read_lock(&in_dev->mc_list_lock);
2226 	for (im=in_dev->mc_list; im; im=im->next) {
2227 		if (im->multiaddr == mc_addr)
2228 			break;
2229 	}
2230 	if (im && proto == IPPROTO_IGMP) {
2231 		rv = 1;
2232 	} else if (im) {
2233 		if (src_addr) {
2234 			for (psf=im->sources; psf; psf=psf->sf_next) {
2235 				if (psf->sf_inaddr == src_addr)
2236 					break;
2237 			}
2238 			if (psf)
2239 				rv = psf->sf_count[MCAST_INCLUDE] ||
2240 					psf->sf_count[MCAST_EXCLUDE] !=
2241 					im->sfcount[MCAST_EXCLUDE];
2242 			else
2243 				rv = im->sfcount[MCAST_EXCLUDE] != 0;
2244 		} else
2245 			rv = 1; /* unspecified source; tentatively allow */
2246 	}
2247 	read_unlock(&in_dev->mc_list_lock);
2248 	return rv;
2249 }
2250 
2251 #if defined(CONFIG_PROC_FS)
2252 struct igmp_mc_iter_state {
2253 	struct net_device *dev;
2254 	struct in_device *in_dev;
2255 };
2256 
2257 #define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2258 
2259 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2260 {
2261 	struct ip_mc_list *im = NULL;
2262 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2263 
2264 	for (state->dev = dev_base, state->in_dev = NULL;
2265 	     state->dev;
2266 	     state->dev = state->dev->next) {
2267 		struct in_device *in_dev;
2268 		in_dev = in_dev_get(state->dev);
2269 		if (!in_dev)
2270 			continue;
2271 		read_lock(&in_dev->mc_list_lock);
2272 		im = in_dev->mc_list;
2273 		if (im) {
2274 			state->in_dev = in_dev;
2275 			break;
2276 		}
2277 		read_unlock(&in_dev->mc_list_lock);
2278 		in_dev_put(in_dev);
2279 	}
2280 	return im;
2281 }
2282 
2283 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2284 {
2285 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2286 	im = im->next;
2287 	while (!im) {
2288 		if (likely(state->in_dev != NULL)) {
2289 			read_unlock(&state->in_dev->mc_list_lock);
2290 			in_dev_put(state->in_dev);
2291 		}
2292 		state->dev = state->dev->next;
2293 		if (!state->dev) {
2294 			state->in_dev = NULL;
2295 			break;
2296 		}
2297 		state->in_dev = in_dev_get(state->dev);
2298 		if (!state->in_dev)
2299 			continue;
2300 		read_lock(&state->in_dev->mc_list_lock);
2301 		im = state->in_dev->mc_list;
2302 	}
2303 	return im;
2304 }
2305 
2306 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2307 {
2308 	struct ip_mc_list *im = igmp_mc_get_first(seq);
2309 	if (im)
2310 		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2311 			--pos;
2312 	return pos ? NULL : im;
2313 }
2314 
2315 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2316 {
2317 	read_lock(&dev_base_lock);
2318 	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2319 }
2320 
2321 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2322 {
2323 	struct ip_mc_list *im;
2324 	if (v == SEQ_START_TOKEN)
2325 		im = igmp_mc_get_first(seq);
2326 	else
2327 		im = igmp_mc_get_next(seq, v);
2328 	++*pos;
2329 	return im;
2330 }
2331 
2332 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2333 {
2334 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2335 	if (likely(state->in_dev != NULL)) {
2336 		read_unlock(&state->in_dev->mc_list_lock);
2337 		in_dev_put(state->in_dev);
2338 		state->in_dev = NULL;
2339 	}
2340 	state->dev = NULL;
2341 	read_unlock(&dev_base_lock);
2342 }
2343 
2344 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2345 {
2346 	if (v == SEQ_START_TOKEN)
2347 		seq_puts(seq,
2348 			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2349 	else {
2350 		struct ip_mc_list *im = (struct ip_mc_list *)v;
2351 		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2352 		char   *querier;
2353 #ifdef CONFIG_IP_MULTICAST
2354 		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2355 			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2356 			  "V3";
2357 #else
2358 		querier = "NONE";
2359 #endif
2360 
2361 		if (state->in_dev->mc_list == im) {
2362 			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2363 				   state->dev->ifindex, state->dev->name, state->dev->mc_count, querier);
2364 		}
2365 
2366 		seq_printf(seq,
2367 			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2368 			   im->multiaddr, im->users,
2369 			   im->tm_running, im->tm_running ?
2370 			   jiffies_to_clock_t(im->timer.expires-jiffies) : 0,
2371 			   im->reporter);
2372 	}
2373 	return 0;
2374 }
2375 
2376 static struct seq_operations igmp_mc_seq_ops = {
2377 	.start	=	igmp_mc_seq_start,
2378 	.next	=	igmp_mc_seq_next,
2379 	.stop	=	igmp_mc_seq_stop,
2380 	.show	=	igmp_mc_seq_show,
2381 };
2382 
2383 static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2384 {
2385 	struct seq_file *seq;
2386 	int rc = -ENOMEM;
2387 	struct igmp_mc_iter_state *s = kzalloc(sizeof(*s), GFP_KERNEL);
2388 
2389 	if (!s)
2390 		goto out;
2391 	rc = seq_open(file, &igmp_mc_seq_ops);
2392 	if (rc)
2393 		goto out_kfree;
2394 
2395 	seq = file->private_data;
2396 	seq->private = s;
2397 out:
2398 	return rc;
2399 out_kfree:
2400 	kfree(s);
2401 	goto out;
2402 }
2403 
2404 static struct file_operations igmp_mc_seq_fops = {
2405 	.owner		=	THIS_MODULE,
2406 	.open		=	igmp_mc_seq_open,
2407 	.read		=	seq_read,
2408 	.llseek		=	seq_lseek,
2409 	.release	=	seq_release_private,
2410 };
2411 
2412 struct igmp_mcf_iter_state {
2413 	struct net_device *dev;
2414 	struct in_device *idev;
2415 	struct ip_mc_list *im;
2416 };
2417 
2418 #define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2419 
2420 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2421 {
2422 	struct ip_sf_list *psf = NULL;
2423 	struct ip_mc_list *im = NULL;
2424 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2425 
2426 	for (state->dev = dev_base, state->idev = NULL, state->im = NULL;
2427 	     state->dev;
2428 	     state->dev = state->dev->next) {
2429 		struct in_device *idev;
2430 		idev = in_dev_get(state->dev);
2431 		if (unlikely(idev == NULL))
2432 			continue;
2433 		read_lock(&idev->mc_list_lock);
2434 		im = idev->mc_list;
2435 		if (likely(im != NULL)) {
2436 			spin_lock_bh(&im->lock);
2437 			psf = im->sources;
2438 			if (likely(psf != NULL)) {
2439 				state->im = im;
2440 				state->idev = idev;
2441 				break;
2442 			}
2443 			spin_unlock_bh(&im->lock);
2444 		}
2445 		read_unlock(&idev->mc_list_lock);
2446 		in_dev_put(idev);
2447 	}
2448 	return psf;
2449 }
2450 
2451 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2452 {
2453 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2454 
2455 	psf = psf->sf_next;
2456 	while (!psf) {
2457 		spin_unlock_bh(&state->im->lock);
2458 		state->im = state->im->next;
2459 		while (!state->im) {
2460 			if (likely(state->idev != NULL)) {
2461 				read_unlock(&state->idev->mc_list_lock);
2462 				in_dev_put(state->idev);
2463 			}
2464 			state->dev = state->dev->next;
2465 			if (!state->dev) {
2466 				state->idev = NULL;
2467 				goto out;
2468 			}
2469 			state->idev = in_dev_get(state->dev);
2470 			if (!state->idev)
2471 				continue;
2472 			read_lock(&state->idev->mc_list_lock);
2473 			state->im = state->idev->mc_list;
2474 		}
2475 		if (!state->im)
2476 			break;
2477 		spin_lock_bh(&state->im->lock);
2478 		psf = state->im->sources;
2479 	}
2480 out:
2481 	return psf;
2482 }
2483 
2484 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2485 {
2486 	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2487 	if (psf)
2488 		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2489 			--pos;
2490 	return pos ? NULL : psf;
2491 }
2492 
2493 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2494 {
2495 	read_lock(&dev_base_lock);
2496 	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2497 }
2498 
2499 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2500 {
2501 	struct ip_sf_list *psf;
2502 	if (v == SEQ_START_TOKEN)
2503 		psf = igmp_mcf_get_first(seq);
2504 	else
2505 		psf = igmp_mcf_get_next(seq, v);
2506 	++*pos;
2507 	return psf;
2508 }
2509 
2510 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2511 {
2512 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2513 	if (likely(state->im != NULL)) {
2514 		spin_unlock_bh(&state->im->lock);
2515 		state->im = NULL;
2516 	}
2517 	if (likely(state->idev != NULL)) {
2518 		read_unlock(&state->idev->mc_list_lock);
2519 		in_dev_put(state->idev);
2520 		state->idev = NULL;
2521 	}
2522 	state->dev = NULL;
2523 	read_unlock(&dev_base_lock);
2524 }
2525 
2526 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2527 {
2528 	struct ip_sf_list *psf = (struct ip_sf_list *)v;
2529 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2530 
2531 	if (v == SEQ_START_TOKEN) {
2532 		seq_printf(seq,
2533 			   "%3s %6s "
2534 			   "%10s %10s %6s %6s\n", "Idx",
2535 			   "Device", "MCA",
2536 			   "SRC", "INC", "EXC");
2537 	} else {
2538 		seq_printf(seq,
2539 			   "%3d %6.6s 0x%08x "
2540 			   "0x%08x %6lu %6lu\n",
2541 			   state->dev->ifindex, state->dev->name,
2542 			   ntohl(state->im->multiaddr),
2543 			   ntohl(psf->sf_inaddr),
2544 			   psf->sf_count[MCAST_INCLUDE],
2545 			   psf->sf_count[MCAST_EXCLUDE]);
2546 	}
2547 	return 0;
2548 }
2549 
2550 static struct seq_operations igmp_mcf_seq_ops = {
2551 	.start	=	igmp_mcf_seq_start,
2552 	.next	=	igmp_mcf_seq_next,
2553 	.stop	=	igmp_mcf_seq_stop,
2554 	.show	=	igmp_mcf_seq_show,
2555 };
2556 
2557 static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2558 {
2559 	struct seq_file *seq;
2560 	int rc = -ENOMEM;
2561 	struct igmp_mcf_iter_state *s = kzalloc(sizeof(*s), GFP_KERNEL);
2562 
2563 	if (!s)
2564 		goto out;
2565 	rc = seq_open(file, &igmp_mcf_seq_ops);
2566 	if (rc)
2567 		goto out_kfree;
2568 
2569 	seq = file->private_data;
2570 	seq->private = s;
2571 out:
2572 	return rc;
2573 out_kfree:
2574 	kfree(s);
2575 	goto out;
2576 }
2577 
2578 static struct file_operations igmp_mcf_seq_fops = {
2579 	.owner		=	THIS_MODULE,
2580 	.open		=	igmp_mcf_seq_open,
2581 	.read		=	seq_read,
2582 	.llseek		=	seq_lseek,
2583 	.release	=	seq_release_private,
2584 };
2585 
2586 int __init igmp_mc_proc_init(void)
2587 {
2588 	proc_net_fops_create("igmp", S_IRUGO, &igmp_mc_seq_fops);
2589 	proc_net_fops_create("mcfilter", S_IRUGO, &igmp_mcf_seq_fops);
2590 	return 0;
2591 }
2592 #endif
2593 
2594 EXPORT_SYMBOL(ip_mc_dec_group);
2595 EXPORT_SYMBOL(ip_mc_inc_group);
2596 EXPORT_SYMBOL(ip_mc_join_group);
2597