xref: /openbmc/linux/net/ipv4/igmp.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
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/net_namespace.h>
95 #include <net/arp.h>
96 #include <net/ip.h>
97 #include <net/protocol.h>
98 #include <net/route.h>
99 #include <net/sock.h>
100 #include <net/checksum.h>
101 #include <linux/netfilter_ipv4.h>
102 #ifdef CONFIG_IP_MROUTE
103 #include <linux/mroute.h>
104 #endif
105 #ifdef CONFIG_PROC_FS
106 #include <linux/proc_fs.h>
107 #include <linux/seq_file.h>
108 #endif
109 
110 #define IP_MAX_MEMBERSHIPS	20
111 #define IP_MAX_MSF		10
112 
113 #ifdef CONFIG_IP_MULTICAST
114 /* Parameter names and values are taken from igmp-v2-06 draft */
115 
116 #define IGMP_V1_Router_Present_Timeout		(400*HZ)
117 #define IGMP_V2_Router_Present_Timeout		(400*HZ)
118 #define IGMP_Unsolicited_Report_Interval	(10*HZ)
119 #define IGMP_Query_Response_Interval		(10*HZ)
120 #define IGMP_Unsolicited_Report_Count		2
121 
122 
123 #define IGMP_Initial_Report_Delay		(1)
124 
125 /* IGMP_Initial_Report_Delay is not from IGMP specs!
126  * IGMP specs require to report membership immediately after
127  * joining a group, but we delay the first report by a
128  * small interval. It seems more natural and still does not
129  * contradict to specs provided this delay is small enough.
130  */
131 
132 #define IGMP_V1_SEEN(in_dev) \
133 	(IPV4_DEVCONF_ALL(FORCE_IGMP_VERSION) == 1 || \
134 	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \
135 	 ((in_dev)->mr_v1_seen && \
136 	  time_before(jiffies, (in_dev)->mr_v1_seen)))
137 #define IGMP_V2_SEEN(in_dev) \
138 	(IPV4_DEVCONF_ALL(FORCE_IGMP_VERSION) == 2 || \
139 	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \
140 	 ((in_dev)->mr_v2_seen && \
141 	  time_before(jiffies, (in_dev)->mr_v2_seen)))
142 
143 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im);
144 static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr);
145 static void igmpv3_clear_delrec(struct in_device *in_dev);
146 static int sf_setstate(struct ip_mc_list *pmc);
147 static void sf_markstate(struct ip_mc_list *pmc);
148 #endif
149 static void ip_mc_clear_src(struct ip_mc_list *pmc);
150 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
151 			 int sfcount, __be32 *psfsrc, int delta);
152 
153 static void ip_ma_put(struct ip_mc_list *im)
154 {
155 	if (atomic_dec_and_test(&im->refcnt)) {
156 		in_dev_put(im->interface);
157 		kfree(im);
158 	}
159 }
160 
161 #ifdef CONFIG_IP_MULTICAST
162 
163 /*
164  *	Timer management
165  */
166 
167 static __inline__ void igmp_stop_timer(struct ip_mc_list *im)
168 {
169 	spin_lock_bh(&im->lock);
170 	if (del_timer(&im->timer))
171 		atomic_dec(&im->refcnt);
172 	im->tm_running=0;
173 	im->reporter = 0;
174 	im->unsolicit_count = 0;
175 	spin_unlock_bh(&im->lock);
176 }
177 
178 /* It must be called with locked im->lock */
179 static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
180 {
181 	int tv=net_random() % max_delay;
182 
183 	im->tm_running=1;
184 	if (!mod_timer(&im->timer, jiffies+tv+2))
185 		atomic_inc(&im->refcnt);
186 }
187 
188 static void igmp_gq_start_timer(struct in_device *in_dev)
189 {
190 	int tv = net_random() % in_dev->mr_maxdelay;
191 
192 	in_dev->mr_gq_running = 1;
193 	if (!mod_timer(&in_dev->mr_gq_timer, jiffies+tv+2))
194 		in_dev_hold(in_dev);
195 }
196 
197 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
198 {
199 	int tv = net_random() % delay;
200 
201 	if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
202 		in_dev_hold(in_dev);
203 }
204 
205 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
206 {
207 	spin_lock_bh(&im->lock);
208 	im->unsolicit_count = 0;
209 	if (del_timer(&im->timer)) {
210 		if ((long)(im->timer.expires-jiffies) < max_delay) {
211 			add_timer(&im->timer);
212 			im->tm_running=1;
213 			spin_unlock_bh(&im->lock);
214 			return;
215 		}
216 		atomic_dec(&im->refcnt);
217 	}
218 	igmp_start_timer(im, max_delay);
219 	spin_unlock_bh(&im->lock);
220 }
221 
222 
223 /*
224  *	Send an IGMP report.
225  */
226 
227 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
228 
229 
230 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
231 	int gdeleted, int sdeleted)
232 {
233 	switch (type) {
234 	case IGMPV3_MODE_IS_INCLUDE:
235 	case IGMPV3_MODE_IS_EXCLUDE:
236 		if (gdeleted || sdeleted)
237 			return 0;
238 		if (!(pmc->gsquery && !psf->sf_gsresp)) {
239 			if (pmc->sfmode == MCAST_INCLUDE)
240 				return 1;
241 			/* don't include if this source is excluded
242 			 * in all filters
243 			 */
244 			if (psf->sf_count[MCAST_INCLUDE])
245 				return type == IGMPV3_MODE_IS_INCLUDE;
246 			return pmc->sfcount[MCAST_EXCLUDE] ==
247 				psf->sf_count[MCAST_EXCLUDE];
248 		}
249 		return 0;
250 	case IGMPV3_CHANGE_TO_INCLUDE:
251 		if (gdeleted || sdeleted)
252 			return 0;
253 		return psf->sf_count[MCAST_INCLUDE] != 0;
254 	case IGMPV3_CHANGE_TO_EXCLUDE:
255 		if (gdeleted || sdeleted)
256 			return 0;
257 		if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
258 		    psf->sf_count[MCAST_INCLUDE])
259 			return 0;
260 		return pmc->sfcount[MCAST_EXCLUDE] ==
261 			psf->sf_count[MCAST_EXCLUDE];
262 	case IGMPV3_ALLOW_NEW_SOURCES:
263 		if (gdeleted || !psf->sf_crcount)
264 			return 0;
265 		return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
266 	case IGMPV3_BLOCK_OLD_SOURCES:
267 		if (pmc->sfmode == MCAST_INCLUDE)
268 			return gdeleted || (psf->sf_crcount && sdeleted);
269 		return psf->sf_crcount && !gdeleted && !sdeleted;
270 	}
271 	return 0;
272 }
273 
274 static int
275 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
276 {
277 	struct ip_sf_list *psf;
278 	int scount = 0;
279 
280 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
281 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
282 			continue;
283 		scount++;
284 	}
285 	return scount;
286 }
287 
288 static struct sk_buff *igmpv3_newpack(struct net_device *dev, int size)
289 {
290 	struct sk_buff *skb;
291 	struct rtable *rt;
292 	struct iphdr *pip;
293 	struct igmpv3_report *pig;
294 
295 	skb = alloc_skb(size + LL_RESERVED_SPACE(dev), GFP_ATOMIC);
296 	if (skb == NULL)
297 		return NULL;
298 
299 	{
300 		struct flowi fl = { .oif = dev->ifindex,
301 				    .nl_u = { .ip4_u = {
302 				    .daddr = IGMPV3_ALL_MCR } },
303 				    .proto = IPPROTO_IGMP };
304 		if (ip_route_output_key(&rt, &fl)) {
305 			kfree_skb(skb);
306 			return NULL;
307 		}
308 	}
309 	if (rt->rt_src == 0) {
310 		kfree_skb(skb);
311 		ip_rt_put(rt);
312 		return NULL;
313 	}
314 
315 	skb->dst = &rt->u.dst;
316 	skb->dev = dev;
317 
318 	skb_reserve(skb, LL_RESERVED_SPACE(dev));
319 
320 	skb_reset_network_header(skb);
321 	pip = ip_hdr(skb);
322 	skb_put(skb, sizeof(struct iphdr) + 4);
323 
324 	pip->version  = 4;
325 	pip->ihl      = (sizeof(struct iphdr)+4)>>2;
326 	pip->tos      = 0xc0;
327 	pip->frag_off = htons(IP_DF);
328 	pip->ttl      = 1;
329 	pip->daddr    = rt->rt_dst;
330 	pip->saddr    = rt->rt_src;
331 	pip->protocol = IPPROTO_IGMP;
332 	pip->tot_len  = 0;	/* filled in later */
333 	ip_select_ident(pip, &rt->u.dst, NULL);
334 	((u8*)&pip[1])[0] = IPOPT_RA;
335 	((u8*)&pip[1])[1] = 4;
336 	((u8*)&pip[1])[2] = 0;
337 	((u8*)&pip[1])[3] = 0;
338 
339 	skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
340 	skb_put(skb, sizeof(*pig));
341 	pig = igmpv3_report_hdr(skb);
342 	pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
343 	pig->resv1 = 0;
344 	pig->csum = 0;
345 	pig->resv2 = 0;
346 	pig->ngrec = 0;
347 	return skb;
348 }
349 
350 static int igmpv3_sendpack(struct sk_buff *skb)
351 {
352 	struct iphdr *pip = ip_hdr(skb);
353 	struct igmphdr *pig = igmp_hdr(skb);
354 	const int iplen = skb->tail - skb->network_header;
355 	const int igmplen = skb->tail - skb->transport_header;
356 
357 	pip->tot_len = htons(iplen);
358 	ip_send_check(pip);
359 	pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
360 
361 	return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, skb->dev,
362 		       dst_output);
363 }
364 
365 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
366 {
367 	return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc,type,gdel,sdel);
368 }
369 
370 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
371 	int type, struct igmpv3_grec **ppgr)
372 {
373 	struct net_device *dev = pmc->interface->dev;
374 	struct igmpv3_report *pih;
375 	struct igmpv3_grec *pgr;
376 
377 	if (!skb)
378 		skb = igmpv3_newpack(dev, dev->mtu);
379 	if (!skb)
380 		return NULL;
381 	pgr = (struct igmpv3_grec *)skb_put(skb, sizeof(struct igmpv3_grec));
382 	pgr->grec_type = type;
383 	pgr->grec_auxwords = 0;
384 	pgr->grec_nsrcs = 0;
385 	pgr->grec_mca = pmc->multiaddr;
386 	pih = igmpv3_report_hdr(skb);
387 	pih->ngrec = htons(ntohs(pih->ngrec)+1);
388 	*ppgr = pgr;
389 	return skb;
390 }
391 
392 #define AVAILABLE(skb) ((skb) ? ((skb)->dev ? (skb)->dev->mtu - (skb)->len : \
393 	skb_tailroom(skb)) : 0)
394 
395 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
396 	int type, int gdeleted, int sdeleted)
397 {
398 	struct net_device *dev = pmc->interface->dev;
399 	struct igmpv3_report *pih;
400 	struct igmpv3_grec *pgr = NULL;
401 	struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
402 	int scount, stotal, first, isquery, truncate;
403 
404 	if (pmc->multiaddr == IGMP_ALL_HOSTS)
405 		return skb;
406 
407 	isquery = type == IGMPV3_MODE_IS_INCLUDE ||
408 		  type == IGMPV3_MODE_IS_EXCLUDE;
409 	truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
410 		    type == IGMPV3_CHANGE_TO_EXCLUDE;
411 
412 	stotal = scount = 0;
413 
414 	psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
415 
416 	if (!*psf_list)
417 		goto empty_source;
418 
419 	pih = skb ? igmpv3_report_hdr(skb) : NULL;
420 
421 	/* EX and TO_EX get a fresh packet, if needed */
422 	if (truncate) {
423 		if (pih && pih->ngrec &&
424 		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
425 			if (skb)
426 				igmpv3_sendpack(skb);
427 			skb = igmpv3_newpack(dev, dev->mtu);
428 		}
429 	}
430 	first = 1;
431 	psf_prev = NULL;
432 	for (psf=*psf_list; psf; psf=psf_next) {
433 		__be32 *psrc;
434 
435 		psf_next = psf->sf_next;
436 
437 		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
438 			psf_prev = psf;
439 			continue;
440 		}
441 
442 		/* clear marks on query responses */
443 		if (isquery)
444 			psf->sf_gsresp = 0;
445 
446 		if (AVAILABLE(skb) < sizeof(__be32) +
447 		    first*sizeof(struct igmpv3_grec)) {
448 			if (truncate && !first)
449 				break;	 /* truncate these */
450 			if (pgr)
451 				pgr->grec_nsrcs = htons(scount);
452 			if (skb)
453 				igmpv3_sendpack(skb);
454 			skb = igmpv3_newpack(dev, dev->mtu);
455 			first = 1;
456 			scount = 0;
457 		}
458 		if (first) {
459 			skb = add_grhead(skb, pmc, type, &pgr);
460 			first = 0;
461 		}
462 		if (!skb)
463 			return NULL;
464 		psrc = (__be32 *)skb_put(skb, sizeof(__be32));
465 		*psrc = psf->sf_inaddr;
466 		scount++; stotal++;
467 		if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
468 		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
469 			psf->sf_crcount--;
470 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
471 				if (psf_prev)
472 					psf_prev->sf_next = psf->sf_next;
473 				else
474 					*psf_list = psf->sf_next;
475 				kfree(psf);
476 				continue;
477 			}
478 		}
479 		psf_prev = psf;
480 	}
481 
482 empty_source:
483 	if (!stotal) {
484 		if (type == IGMPV3_ALLOW_NEW_SOURCES ||
485 		    type == IGMPV3_BLOCK_OLD_SOURCES)
486 			return skb;
487 		if (pmc->crcount || isquery) {
488 			/* make sure we have room for group header */
489 			if (skb && AVAILABLE(skb)<sizeof(struct igmpv3_grec)) {
490 				igmpv3_sendpack(skb);
491 				skb = NULL; /* add_grhead will get a new one */
492 			}
493 			skb = add_grhead(skb, pmc, type, &pgr);
494 		}
495 	}
496 	if (pgr)
497 		pgr->grec_nsrcs = htons(scount);
498 
499 	if (isquery)
500 		pmc->gsquery = 0;	/* clear query state on report */
501 	return skb;
502 }
503 
504 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
505 {
506 	struct sk_buff *skb = NULL;
507 	int type;
508 
509 	if (!pmc) {
510 		read_lock(&in_dev->mc_list_lock);
511 		for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
512 			if (pmc->multiaddr == IGMP_ALL_HOSTS)
513 				continue;
514 			spin_lock_bh(&pmc->lock);
515 			if (pmc->sfcount[MCAST_EXCLUDE])
516 				type = IGMPV3_MODE_IS_EXCLUDE;
517 			else
518 				type = IGMPV3_MODE_IS_INCLUDE;
519 			skb = add_grec(skb, pmc, type, 0, 0);
520 			spin_unlock_bh(&pmc->lock);
521 		}
522 		read_unlock(&in_dev->mc_list_lock);
523 	} else {
524 		spin_lock_bh(&pmc->lock);
525 		if (pmc->sfcount[MCAST_EXCLUDE])
526 			type = IGMPV3_MODE_IS_EXCLUDE;
527 		else
528 			type = IGMPV3_MODE_IS_INCLUDE;
529 		skb = add_grec(skb, pmc, type, 0, 0);
530 		spin_unlock_bh(&pmc->lock);
531 	}
532 	if (!skb)
533 		return 0;
534 	return igmpv3_sendpack(skb);
535 }
536 
537 /*
538  * remove zero-count source records from a source filter list
539  */
540 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
541 {
542 	struct ip_sf_list *psf_prev, *psf_next, *psf;
543 
544 	psf_prev = NULL;
545 	for (psf=*ppsf; psf; psf = psf_next) {
546 		psf_next = psf->sf_next;
547 		if (psf->sf_crcount == 0) {
548 			if (psf_prev)
549 				psf_prev->sf_next = psf->sf_next;
550 			else
551 				*ppsf = psf->sf_next;
552 			kfree(psf);
553 		} else
554 			psf_prev = psf;
555 	}
556 }
557 
558 static void igmpv3_send_cr(struct in_device *in_dev)
559 {
560 	struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
561 	struct sk_buff *skb = NULL;
562 	int type, dtype;
563 
564 	read_lock(&in_dev->mc_list_lock);
565 	spin_lock_bh(&in_dev->mc_tomb_lock);
566 
567 	/* deleted MCA's */
568 	pmc_prev = NULL;
569 	for (pmc=in_dev->mc_tomb; pmc; pmc=pmc_next) {
570 		pmc_next = pmc->next;
571 		if (pmc->sfmode == MCAST_INCLUDE) {
572 			type = IGMPV3_BLOCK_OLD_SOURCES;
573 			dtype = IGMPV3_BLOCK_OLD_SOURCES;
574 			skb = add_grec(skb, pmc, type, 1, 0);
575 			skb = add_grec(skb, pmc, dtype, 1, 1);
576 		}
577 		if (pmc->crcount) {
578 			if (pmc->sfmode == MCAST_EXCLUDE) {
579 				type = IGMPV3_CHANGE_TO_INCLUDE;
580 				skb = add_grec(skb, pmc, type, 1, 0);
581 			}
582 			pmc->crcount--;
583 			if (pmc->crcount == 0) {
584 				igmpv3_clear_zeros(&pmc->tomb);
585 				igmpv3_clear_zeros(&pmc->sources);
586 			}
587 		}
588 		if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
589 			if (pmc_prev)
590 				pmc_prev->next = pmc_next;
591 			else
592 				in_dev->mc_tomb = pmc_next;
593 			in_dev_put(pmc->interface);
594 			kfree(pmc);
595 		} else
596 			pmc_prev = pmc;
597 	}
598 	spin_unlock_bh(&in_dev->mc_tomb_lock);
599 
600 	/* change recs */
601 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
602 		spin_lock_bh(&pmc->lock);
603 		if (pmc->sfcount[MCAST_EXCLUDE]) {
604 			type = IGMPV3_BLOCK_OLD_SOURCES;
605 			dtype = IGMPV3_ALLOW_NEW_SOURCES;
606 		} else {
607 			type = IGMPV3_ALLOW_NEW_SOURCES;
608 			dtype = IGMPV3_BLOCK_OLD_SOURCES;
609 		}
610 		skb = add_grec(skb, pmc, type, 0, 0);
611 		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
612 
613 		/* filter mode changes */
614 		if (pmc->crcount) {
615 			if (pmc->sfmode == MCAST_EXCLUDE)
616 				type = IGMPV3_CHANGE_TO_EXCLUDE;
617 			else
618 				type = IGMPV3_CHANGE_TO_INCLUDE;
619 			skb = add_grec(skb, pmc, type, 0, 0);
620 			pmc->crcount--;
621 		}
622 		spin_unlock_bh(&pmc->lock);
623 	}
624 	read_unlock(&in_dev->mc_list_lock);
625 
626 	if (!skb)
627 		return;
628 	(void) igmpv3_sendpack(skb);
629 }
630 
631 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
632 	int type)
633 {
634 	struct sk_buff *skb;
635 	struct iphdr *iph;
636 	struct igmphdr *ih;
637 	struct rtable *rt;
638 	struct net_device *dev = in_dev->dev;
639 	__be32	group = pmc ? pmc->multiaddr : 0;
640 	__be32	dst;
641 
642 	if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
643 		return igmpv3_send_report(in_dev, pmc);
644 	else if (type == IGMP_HOST_LEAVE_MESSAGE)
645 		dst = IGMP_ALL_ROUTER;
646 	else
647 		dst = group;
648 
649 	{
650 		struct flowi fl = { .oif = dev->ifindex,
651 				    .nl_u = { .ip4_u = { .daddr = dst } },
652 				    .proto = IPPROTO_IGMP };
653 		if (ip_route_output_key(&rt, &fl))
654 			return -1;
655 	}
656 	if (rt->rt_src == 0) {
657 		ip_rt_put(rt);
658 		return -1;
659 	}
660 
661 	skb=alloc_skb(IGMP_SIZE+LL_RESERVED_SPACE(dev), GFP_ATOMIC);
662 	if (skb == NULL) {
663 		ip_rt_put(rt);
664 		return -1;
665 	}
666 
667 	skb->dst = &rt->u.dst;
668 
669 	skb_reserve(skb, LL_RESERVED_SPACE(dev));
670 
671 	skb_reset_network_header(skb);
672 	iph = ip_hdr(skb);
673 	skb_put(skb, sizeof(struct iphdr) + 4);
674 
675 	iph->version  = 4;
676 	iph->ihl      = (sizeof(struct iphdr)+4)>>2;
677 	iph->tos      = 0xc0;
678 	iph->frag_off = htons(IP_DF);
679 	iph->ttl      = 1;
680 	iph->daddr    = dst;
681 	iph->saddr    = rt->rt_src;
682 	iph->protocol = IPPROTO_IGMP;
683 	iph->tot_len  = htons(IGMP_SIZE);
684 	ip_select_ident(iph, &rt->u.dst, NULL);
685 	((u8*)&iph[1])[0] = IPOPT_RA;
686 	((u8*)&iph[1])[1] = 4;
687 	((u8*)&iph[1])[2] = 0;
688 	((u8*)&iph[1])[3] = 0;
689 	ip_send_check(iph);
690 
691 	ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
692 	ih->type=type;
693 	ih->code=0;
694 	ih->csum=0;
695 	ih->group=group;
696 	ih->csum=ip_compute_csum((void *)ih, sizeof(struct igmphdr));
697 
698 	return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, rt->u.dst.dev,
699 		       dst_output);
700 }
701 
702 static void igmp_gq_timer_expire(unsigned long data)
703 {
704 	struct in_device *in_dev = (struct in_device *)data;
705 
706 	in_dev->mr_gq_running = 0;
707 	igmpv3_send_report(in_dev, NULL);
708 	__in_dev_put(in_dev);
709 }
710 
711 static void igmp_ifc_timer_expire(unsigned long data)
712 {
713 	struct in_device *in_dev = (struct in_device *)data;
714 
715 	igmpv3_send_cr(in_dev);
716 	if (in_dev->mr_ifc_count) {
717 		in_dev->mr_ifc_count--;
718 		igmp_ifc_start_timer(in_dev, IGMP_Unsolicited_Report_Interval);
719 	}
720 	__in_dev_put(in_dev);
721 }
722 
723 static void igmp_ifc_event(struct in_device *in_dev)
724 {
725 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
726 		return;
727 	in_dev->mr_ifc_count = in_dev->mr_qrv ? in_dev->mr_qrv :
728 		IGMP_Unsolicited_Report_Count;
729 	igmp_ifc_start_timer(in_dev, 1);
730 }
731 
732 
733 static void igmp_timer_expire(unsigned long data)
734 {
735 	struct ip_mc_list *im=(struct ip_mc_list *)data;
736 	struct in_device *in_dev = im->interface;
737 
738 	spin_lock(&im->lock);
739 	im->tm_running=0;
740 
741 	if (im->unsolicit_count) {
742 		im->unsolicit_count--;
743 		igmp_start_timer(im, IGMP_Unsolicited_Report_Interval);
744 	}
745 	im->reporter = 1;
746 	spin_unlock(&im->lock);
747 
748 	if (IGMP_V1_SEEN(in_dev))
749 		igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
750 	else if (IGMP_V2_SEEN(in_dev))
751 		igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
752 	else
753 		igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
754 
755 	ip_ma_put(im);
756 }
757 
758 /* mark EXCLUDE-mode sources */
759 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
760 {
761 	struct ip_sf_list *psf;
762 	int i, scount;
763 
764 	scount = 0;
765 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
766 		if (scount == nsrcs)
767 			break;
768 		for (i=0; i<nsrcs; i++) {
769 			/* skip inactive filters */
770 			if (pmc->sfcount[MCAST_INCLUDE] ||
771 			    pmc->sfcount[MCAST_EXCLUDE] !=
772 			    psf->sf_count[MCAST_EXCLUDE])
773 				continue;
774 			if (srcs[i] == psf->sf_inaddr) {
775 				scount++;
776 				break;
777 			}
778 		}
779 	}
780 	pmc->gsquery = 0;
781 	if (scount == nsrcs)	/* all sources excluded */
782 		return 0;
783 	return 1;
784 }
785 
786 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
787 {
788 	struct ip_sf_list *psf;
789 	int i, scount;
790 
791 	if (pmc->sfmode == MCAST_EXCLUDE)
792 		return igmp_xmarksources(pmc, nsrcs, srcs);
793 
794 	/* mark INCLUDE-mode sources */
795 	scount = 0;
796 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
797 		if (scount == nsrcs)
798 			break;
799 		for (i=0; i<nsrcs; i++)
800 			if (srcs[i] == psf->sf_inaddr) {
801 				psf->sf_gsresp = 1;
802 				scount++;
803 				break;
804 			}
805 	}
806 	if (!scount) {
807 		pmc->gsquery = 0;
808 		return 0;
809 	}
810 	pmc->gsquery = 1;
811 	return 1;
812 }
813 
814 static void igmp_heard_report(struct in_device *in_dev, __be32 group)
815 {
816 	struct ip_mc_list *im;
817 
818 	/* Timers are only set for non-local groups */
819 
820 	if (group == IGMP_ALL_HOSTS)
821 		return;
822 
823 	read_lock(&in_dev->mc_list_lock);
824 	for (im=in_dev->mc_list; im!=NULL; im=im->next) {
825 		if (im->multiaddr == group) {
826 			igmp_stop_timer(im);
827 			break;
828 		}
829 	}
830 	read_unlock(&in_dev->mc_list_lock);
831 }
832 
833 static void igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
834 	int len)
835 {
836 	struct igmphdr 		*ih = igmp_hdr(skb);
837 	struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
838 	struct ip_mc_list	*im;
839 	__be32			group = ih->group;
840 	int			max_delay;
841 	int			mark = 0;
842 
843 
844 	if (len == 8) {
845 		if (ih->code == 0) {
846 			/* Alas, old v1 router presents here. */
847 
848 			max_delay = IGMP_Query_Response_Interval;
849 			in_dev->mr_v1_seen = jiffies +
850 				IGMP_V1_Router_Present_Timeout;
851 			group = 0;
852 		} else {
853 			/* v2 router present */
854 			max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
855 			in_dev->mr_v2_seen = jiffies +
856 				IGMP_V2_Router_Present_Timeout;
857 		}
858 		/* cancel the interface change timer */
859 		in_dev->mr_ifc_count = 0;
860 		if (del_timer(&in_dev->mr_ifc_timer))
861 			__in_dev_put(in_dev);
862 		/* clear deleted report items */
863 		igmpv3_clear_delrec(in_dev);
864 	} else if (len < 12) {
865 		return;	/* ignore bogus packet; freed by caller */
866 	} else { /* v3 */
867 		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
868 			return;
869 
870 		ih3 = igmpv3_query_hdr(skb);
871 		if (ih3->nsrcs) {
872 			if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
873 					   + ntohs(ih3->nsrcs)*sizeof(__be32)))
874 				return;
875 			ih3 = igmpv3_query_hdr(skb);
876 		}
877 
878 		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
879 		if (!max_delay)
880 			max_delay = 1;	/* can't mod w/ 0 */
881 		in_dev->mr_maxdelay = max_delay;
882 		if (ih3->qrv)
883 			in_dev->mr_qrv = ih3->qrv;
884 		if (!group) { /* general query */
885 			if (ih3->nsrcs)
886 				return;	/* no sources allowed */
887 			igmp_gq_start_timer(in_dev);
888 			return;
889 		}
890 		/* mark sources to include, if group & source-specific */
891 		mark = ih3->nsrcs != 0;
892 	}
893 
894 	/*
895 	 * - Start the timers in all of our membership records
896 	 *   that the query applies to for the interface on
897 	 *   which the query arrived excl. those that belong
898 	 *   to a "local" group (224.0.0.X)
899 	 * - For timers already running check if they need to
900 	 *   be reset.
901 	 * - Use the igmp->igmp_code field as the maximum
902 	 *   delay possible
903 	 */
904 	read_lock(&in_dev->mc_list_lock);
905 	for (im=in_dev->mc_list; im!=NULL; im=im->next) {
906 		int changed;
907 
908 		if (group && group != im->multiaddr)
909 			continue;
910 		if (im->multiaddr == IGMP_ALL_HOSTS)
911 			continue;
912 		spin_lock_bh(&im->lock);
913 		if (im->tm_running)
914 			im->gsquery = im->gsquery && mark;
915 		else
916 			im->gsquery = mark;
917 		changed = !im->gsquery ||
918 			igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
919 		spin_unlock_bh(&im->lock);
920 		if (changed)
921 			igmp_mod_timer(im, max_delay);
922 	}
923 	read_unlock(&in_dev->mc_list_lock);
924 }
925 
926 int igmp_rcv(struct sk_buff *skb)
927 {
928 	/* This basically follows the spec line by line -- see RFC1112 */
929 	struct igmphdr *ih;
930 	struct in_device *in_dev = in_dev_get(skb->dev);
931 	int len = skb->len;
932 
933 	if (in_dev==NULL) {
934 		kfree_skb(skb);
935 		return 0;
936 	}
937 
938 	if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
939 		goto drop;
940 
941 	switch (skb->ip_summed) {
942 	case CHECKSUM_COMPLETE:
943 		if (!csum_fold(skb->csum))
944 			break;
945 		/* fall through */
946 	case CHECKSUM_NONE:
947 		skb->csum = 0;
948 		if (__skb_checksum_complete(skb))
949 			goto drop;
950 	}
951 
952 	ih = igmp_hdr(skb);
953 	switch (ih->type) {
954 	case IGMP_HOST_MEMBERSHIP_QUERY:
955 		igmp_heard_query(in_dev, skb, len);
956 		break;
957 	case IGMP_HOST_MEMBERSHIP_REPORT:
958 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
959 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
960 		/* Is it our report looped back? */
961 		if (((struct rtable*)skb->dst)->fl.iif == 0)
962 			break;
963 		/* don't rely on MC router hearing unicast reports */
964 		if (skb->pkt_type == PACKET_MULTICAST ||
965 		    skb->pkt_type == PACKET_BROADCAST)
966 			igmp_heard_report(in_dev, ih->group);
967 		break;
968 	case IGMP_PIM:
969 #ifdef CONFIG_IP_PIMSM_V1
970 		in_dev_put(in_dev);
971 		return pim_rcv_v1(skb);
972 #endif
973 	case IGMP_DVMRP:
974 	case IGMP_TRACE:
975 	case IGMP_HOST_LEAVE_MESSAGE:
976 	case IGMP_MTRACE:
977 	case IGMP_MTRACE_RESP:
978 		break;
979 	default:
980 		break;
981 	}
982 
983 drop:
984 	in_dev_put(in_dev);
985 	kfree_skb(skb);
986 	return 0;
987 }
988 
989 #endif
990 
991 
992 /*
993  *	Add a filter to a device
994  */
995 
996 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
997 {
998 	char buf[MAX_ADDR_LEN];
999 	struct net_device *dev = in_dev->dev;
1000 
1001 	/* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1002 	   We will get multicast token leakage, when IFF_MULTICAST
1003 	   is changed. This check should be done in dev->set_multicast_list
1004 	   routine. Something sort of:
1005 	   if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1006 	   --ANK
1007 	   */
1008 	if (arp_mc_map(addr, buf, dev, 0) == 0)
1009 		dev_mc_add(dev,buf,dev->addr_len,0);
1010 }
1011 
1012 /*
1013  *	Remove a filter from a device
1014  */
1015 
1016 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1017 {
1018 	char buf[MAX_ADDR_LEN];
1019 	struct net_device *dev = in_dev->dev;
1020 
1021 	if (arp_mc_map(addr, buf, dev, 0) == 0)
1022 		dev_mc_delete(dev,buf,dev->addr_len,0);
1023 }
1024 
1025 #ifdef CONFIG_IP_MULTICAST
1026 /*
1027  * deleted ip_mc_list manipulation
1028  */
1029 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1030 {
1031 	struct ip_mc_list *pmc;
1032 
1033 	/* this is an "ip_mc_list" for convenience; only the fields below
1034 	 * are actually used. In particular, the refcnt and users are not
1035 	 * used for management of the delete list. Using the same structure
1036 	 * for deleted items allows change reports to use common code with
1037 	 * non-deleted or query-response MCA's.
1038 	 */
1039 	pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
1040 	if (!pmc)
1041 		return;
1042 	spin_lock_bh(&im->lock);
1043 	pmc->interface = im->interface;
1044 	in_dev_hold(in_dev);
1045 	pmc->multiaddr = im->multiaddr;
1046 	pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1047 		IGMP_Unsolicited_Report_Count;
1048 	pmc->sfmode = im->sfmode;
1049 	if (pmc->sfmode == MCAST_INCLUDE) {
1050 		struct ip_sf_list *psf;
1051 
1052 		pmc->tomb = im->tomb;
1053 		pmc->sources = im->sources;
1054 		im->tomb = im->sources = NULL;
1055 		for (psf=pmc->sources; psf; psf=psf->sf_next)
1056 			psf->sf_crcount = pmc->crcount;
1057 	}
1058 	spin_unlock_bh(&im->lock);
1059 
1060 	spin_lock_bh(&in_dev->mc_tomb_lock);
1061 	pmc->next = in_dev->mc_tomb;
1062 	in_dev->mc_tomb = pmc;
1063 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1064 }
1065 
1066 static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr)
1067 {
1068 	struct ip_mc_list *pmc, *pmc_prev;
1069 	struct ip_sf_list *psf, *psf_next;
1070 
1071 	spin_lock_bh(&in_dev->mc_tomb_lock);
1072 	pmc_prev = NULL;
1073 	for (pmc=in_dev->mc_tomb; pmc; pmc=pmc->next) {
1074 		if (pmc->multiaddr == multiaddr)
1075 			break;
1076 		pmc_prev = pmc;
1077 	}
1078 	if (pmc) {
1079 		if (pmc_prev)
1080 			pmc_prev->next = pmc->next;
1081 		else
1082 			in_dev->mc_tomb = pmc->next;
1083 	}
1084 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1085 	if (pmc) {
1086 		for (psf=pmc->tomb; psf; psf=psf_next) {
1087 			psf_next = psf->sf_next;
1088 			kfree(psf);
1089 		}
1090 		in_dev_put(pmc->interface);
1091 		kfree(pmc);
1092 	}
1093 }
1094 
1095 static void igmpv3_clear_delrec(struct in_device *in_dev)
1096 {
1097 	struct ip_mc_list *pmc, *nextpmc;
1098 
1099 	spin_lock_bh(&in_dev->mc_tomb_lock);
1100 	pmc = in_dev->mc_tomb;
1101 	in_dev->mc_tomb = NULL;
1102 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1103 
1104 	for (; pmc; pmc = nextpmc) {
1105 		nextpmc = pmc->next;
1106 		ip_mc_clear_src(pmc);
1107 		in_dev_put(pmc->interface);
1108 		kfree(pmc);
1109 	}
1110 	/* clear dead sources, too */
1111 	read_lock(&in_dev->mc_list_lock);
1112 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1113 		struct ip_sf_list *psf, *psf_next;
1114 
1115 		spin_lock_bh(&pmc->lock);
1116 		psf = pmc->tomb;
1117 		pmc->tomb = NULL;
1118 		spin_unlock_bh(&pmc->lock);
1119 		for (; psf; psf=psf_next) {
1120 			psf_next = psf->sf_next;
1121 			kfree(psf);
1122 		}
1123 	}
1124 	read_unlock(&in_dev->mc_list_lock);
1125 }
1126 #endif
1127 
1128 static void igmp_group_dropped(struct ip_mc_list *im)
1129 {
1130 	struct in_device *in_dev = im->interface;
1131 #ifdef CONFIG_IP_MULTICAST
1132 	int reporter;
1133 #endif
1134 
1135 	if (im->loaded) {
1136 		im->loaded = 0;
1137 		ip_mc_filter_del(in_dev, im->multiaddr);
1138 	}
1139 
1140 #ifdef CONFIG_IP_MULTICAST
1141 	if (im->multiaddr == IGMP_ALL_HOSTS)
1142 		return;
1143 
1144 	reporter = im->reporter;
1145 	igmp_stop_timer(im);
1146 
1147 	if (!in_dev->dead) {
1148 		if (IGMP_V1_SEEN(in_dev))
1149 			goto done;
1150 		if (IGMP_V2_SEEN(in_dev)) {
1151 			if (reporter)
1152 				igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1153 			goto done;
1154 		}
1155 		/* IGMPv3 */
1156 		igmpv3_add_delrec(in_dev, im);
1157 
1158 		igmp_ifc_event(in_dev);
1159 	}
1160 done:
1161 #endif
1162 	ip_mc_clear_src(im);
1163 }
1164 
1165 static void igmp_group_added(struct ip_mc_list *im)
1166 {
1167 	struct in_device *in_dev = im->interface;
1168 
1169 	if (im->loaded == 0) {
1170 		im->loaded = 1;
1171 		ip_mc_filter_add(in_dev, im->multiaddr);
1172 	}
1173 
1174 #ifdef CONFIG_IP_MULTICAST
1175 	if (im->multiaddr == IGMP_ALL_HOSTS)
1176 		return;
1177 
1178 	if (in_dev->dead)
1179 		return;
1180 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1181 		spin_lock_bh(&im->lock);
1182 		igmp_start_timer(im, IGMP_Initial_Report_Delay);
1183 		spin_unlock_bh(&im->lock);
1184 		return;
1185 	}
1186 	/* else, v3 */
1187 
1188 	im->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1189 		IGMP_Unsolicited_Report_Count;
1190 	igmp_ifc_event(in_dev);
1191 #endif
1192 }
1193 
1194 
1195 /*
1196  *	Multicast list managers
1197  */
1198 
1199 
1200 /*
1201  *	A socket has joined a multicast group on device dev.
1202  */
1203 
1204 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1205 {
1206 	struct ip_mc_list *im;
1207 
1208 	ASSERT_RTNL();
1209 
1210 	for (im=in_dev->mc_list; im; im=im->next) {
1211 		if (im->multiaddr == addr) {
1212 			im->users++;
1213 			ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1214 			goto out;
1215 		}
1216 	}
1217 
1218 	im = kmalloc(sizeof(*im), GFP_KERNEL);
1219 	if (!im)
1220 		goto out;
1221 
1222 	im->users=1;
1223 	im->interface=in_dev;
1224 	in_dev_hold(in_dev);
1225 	im->multiaddr=addr;
1226 	/* initial mode is (EX, empty) */
1227 	im->sfmode = MCAST_EXCLUDE;
1228 	im->sfcount[MCAST_INCLUDE] = 0;
1229 	im->sfcount[MCAST_EXCLUDE] = 1;
1230 	im->sources = NULL;
1231 	im->tomb = NULL;
1232 	im->crcount = 0;
1233 	atomic_set(&im->refcnt, 1);
1234 	spin_lock_init(&im->lock);
1235 #ifdef CONFIG_IP_MULTICAST
1236 	im->tm_running=0;
1237 	init_timer(&im->timer);
1238 	im->timer.data=(unsigned long)im;
1239 	im->timer.function=&igmp_timer_expire;
1240 	im->unsolicit_count = IGMP_Unsolicited_Report_Count;
1241 	im->reporter = 0;
1242 	im->gsquery = 0;
1243 #endif
1244 	im->loaded = 0;
1245 	write_lock_bh(&in_dev->mc_list_lock);
1246 	im->next=in_dev->mc_list;
1247 	in_dev->mc_list=im;
1248 	write_unlock_bh(&in_dev->mc_list_lock);
1249 #ifdef CONFIG_IP_MULTICAST
1250 	igmpv3_del_delrec(in_dev, im->multiaddr);
1251 #endif
1252 	igmp_group_added(im);
1253 	if (!in_dev->dead)
1254 		ip_rt_multicast_event(in_dev);
1255 out:
1256 	return;
1257 }
1258 
1259 /*
1260  *	Resend IGMP JOIN report; used for bonding.
1261  */
1262 void ip_mc_rejoin_group(struct ip_mc_list *im)
1263 {
1264 #ifdef CONFIG_IP_MULTICAST
1265 	struct in_device *in_dev = im->interface;
1266 
1267 	if (im->multiaddr == IGMP_ALL_HOSTS)
1268 		return;
1269 
1270 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1271 		igmp_mod_timer(im, IGMP_Initial_Report_Delay);
1272 		return;
1273 	}
1274 	/* else, v3 */
1275 	im->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1276 		IGMP_Unsolicited_Report_Count;
1277 	igmp_ifc_event(in_dev);
1278 #endif
1279 }
1280 
1281 /*
1282  *	A socket has left a multicast group on device dev
1283  */
1284 
1285 void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
1286 {
1287 	struct ip_mc_list *i, **ip;
1288 
1289 	ASSERT_RTNL();
1290 
1291 	for (ip=&in_dev->mc_list; (i=*ip)!=NULL; ip=&i->next) {
1292 		if (i->multiaddr==addr) {
1293 			if (--i->users == 0) {
1294 				write_lock_bh(&in_dev->mc_list_lock);
1295 				*ip = i->next;
1296 				write_unlock_bh(&in_dev->mc_list_lock);
1297 				igmp_group_dropped(i);
1298 
1299 				if (!in_dev->dead)
1300 					ip_rt_multicast_event(in_dev);
1301 
1302 				ip_ma_put(i);
1303 				return;
1304 			}
1305 			break;
1306 		}
1307 	}
1308 }
1309 
1310 /* Device going down */
1311 
1312 void ip_mc_down(struct in_device *in_dev)
1313 {
1314 	struct ip_mc_list *i;
1315 
1316 	ASSERT_RTNL();
1317 
1318 	for (i=in_dev->mc_list; i; i=i->next)
1319 		igmp_group_dropped(i);
1320 
1321 #ifdef CONFIG_IP_MULTICAST
1322 	in_dev->mr_ifc_count = 0;
1323 	if (del_timer(&in_dev->mr_ifc_timer))
1324 		__in_dev_put(in_dev);
1325 	in_dev->mr_gq_running = 0;
1326 	if (del_timer(&in_dev->mr_gq_timer))
1327 		__in_dev_put(in_dev);
1328 	igmpv3_clear_delrec(in_dev);
1329 #endif
1330 
1331 	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1332 }
1333 
1334 void ip_mc_init_dev(struct in_device *in_dev)
1335 {
1336 	ASSERT_RTNL();
1337 
1338 	in_dev->mc_tomb = NULL;
1339 #ifdef CONFIG_IP_MULTICAST
1340 	in_dev->mr_gq_running = 0;
1341 	init_timer(&in_dev->mr_gq_timer);
1342 	in_dev->mr_gq_timer.data=(unsigned long) in_dev;
1343 	in_dev->mr_gq_timer.function=&igmp_gq_timer_expire;
1344 	in_dev->mr_ifc_count = 0;
1345 	init_timer(&in_dev->mr_ifc_timer);
1346 	in_dev->mr_ifc_timer.data=(unsigned long) in_dev;
1347 	in_dev->mr_ifc_timer.function=&igmp_ifc_timer_expire;
1348 	in_dev->mr_qrv = IGMP_Unsolicited_Report_Count;
1349 #endif
1350 
1351 	rwlock_init(&in_dev->mc_list_lock);
1352 	spin_lock_init(&in_dev->mc_tomb_lock);
1353 }
1354 
1355 /* Device going up */
1356 
1357 void ip_mc_up(struct in_device *in_dev)
1358 {
1359 	struct ip_mc_list *i;
1360 
1361 	ASSERT_RTNL();
1362 
1363 	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1364 
1365 	for (i=in_dev->mc_list; i; i=i->next)
1366 		igmp_group_added(i);
1367 }
1368 
1369 /*
1370  *	Device is about to be destroyed: clean up.
1371  */
1372 
1373 void ip_mc_destroy_dev(struct in_device *in_dev)
1374 {
1375 	struct ip_mc_list *i;
1376 
1377 	ASSERT_RTNL();
1378 
1379 	/* Deactivate timers */
1380 	ip_mc_down(in_dev);
1381 
1382 	write_lock_bh(&in_dev->mc_list_lock);
1383 	while ((i = in_dev->mc_list) != NULL) {
1384 		in_dev->mc_list = i->next;
1385 		write_unlock_bh(&in_dev->mc_list_lock);
1386 
1387 		igmp_group_dropped(i);
1388 		ip_ma_put(i);
1389 
1390 		write_lock_bh(&in_dev->mc_list_lock);
1391 	}
1392 	write_unlock_bh(&in_dev->mc_list_lock);
1393 }
1394 
1395 static struct in_device * ip_mc_find_dev(struct ip_mreqn *imr)
1396 {
1397 	struct flowi fl = { .nl_u = { .ip4_u =
1398 				      { .daddr = imr->imr_multiaddr.s_addr } } };
1399 	struct rtable *rt;
1400 	struct net_device *dev = NULL;
1401 	struct in_device *idev = NULL;
1402 
1403 	if (imr->imr_ifindex) {
1404 		idev = inetdev_by_index(imr->imr_ifindex);
1405 		if (idev)
1406 			__in_dev_put(idev);
1407 		return idev;
1408 	}
1409 	if (imr->imr_address.s_addr) {
1410 		dev = ip_dev_find(imr->imr_address.s_addr);
1411 		if (!dev)
1412 			return NULL;
1413 		dev_put(dev);
1414 	}
1415 
1416 	if (!dev && !ip_route_output_key(&rt, &fl)) {
1417 		dev = rt->u.dst.dev;
1418 		ip_rt_put(rt);
1419 	}
1420 	if (dev) {
1421 		imr->imr_ifindex = dev->ifindex;
1422 		idev = __in_dev_get_rtnl(dev);
1423 	}
1424 	return idev;
1425 }
1426 
1427 /*
1428  *	Join a socket to a group
1429  */
1430 int sysctl_igmp_max_memberships __read_mostly = IP_MAX_MEMBERSHIPS;
1431 int sysctl_igmp_max_msf __read_mostly = IP_MAX_MSF;
1432 
1433 
1434 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1435 	__be32 *psfsrc)
1436 {
1437 	struct ip_sf_list *psf, *psf_prev;
1438 	int rv = 0;
1439 
1440 	psf_prev = NULL;
1441 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1442 		if (psf->sf_inaddr == *psfsrc)
1443 			break;
1444 		psf_prev = psf;
1445 	}
1446 	if (!psf || psf->sf_count[sfmode] == 0) {
1447 		/* source filter not found, or count wrong =>  bug */
1448 		return -ESRCH;
1449 	}
1450 	psf->sf_count[sfmode]--;
1451 	if (psf->sf_count[sfmode] == 0) {
1452 		ip_rt_multicast_event(pmc->interface);
1453 	}
1454 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1455 #ifdef CONFIG_IP_MULTICAST
1456 		struct in_device *in_dev = pmc->interface;
1457 #endif
1458 
1459 		/* no more filters for this source */
1460 		if (psf_prev)
1461 			psf_prev->sf_next = psf->sf_next;
1462 		else
1463 			pmc->sources = psf->sf_next;
1464 #ifdef CONFIG_IP_MULTICAST
1465 		if (psf->sf_oldin &&
1466 		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1467 			psf->sf_crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1468 				IGMP_Unsolicited_Report_Count;
1469 			psf->sf_next = pmc->tomb;
1470 			pmc->tomb = psf;
1471 			rv = 1;
1472 		} else
1473 #endif
1474 			kfree(psf);
1475 	}
1476 	return rv;
1477 }
1478 
1479 #ifndef CONFIG_IP_MULTICAST
1480 #define igmp_ifc_event(x)	do { } while (0)
1481 #endif
1482 
1483 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1484 			 int sfcount, __be32 *psfsrc, int delta)
1485 {
1486 	struct ip_mc_list *pmc;
1487 	int	changerec = 0;
1488 	int	i, err;
1489 
1490 	if (!in_dev)
1491 		return -ENODEV;
1492 	read_lock(&in_dev->mc_list_lock);
1493 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1494 		if (*pmca == pmc->multiaddr)
1495 			break;
1496 	}
1497 	if (!pmc) {
1498 		/* MCA not found?? bug */
1499 		read_unlock(&in_dev->mc_list_lock);
1500 		return -ESRCH;
1501 	}
1502 	spin_lock_bh(&pmc->lock);
1503 	read_unlock(&in_dev->mc_list_lock);
1504 #ifdef CONFIG_IP_MULTICAST
1505 	sf_markstate(pmc);
1506 #endif
1507 	if (!delta) {
1508 		err = -EINVAL;
1509 		if (!pmc->sfcount[sfmode])
1510 			goto out_unlock;
1511 		pmc->sfcount[sfmode]--;
1512 	}
1513 	err = 0;
1514 	for (i=0; i<sfcount; i++) {
1515 		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1516 
1517 		changerec |= rv > 0;
1518 		if (!err && rv < 0)
1519 			err = rv;
1520 	}
1521 	if (pmc->sfmode == MCAST_EXCLUDE &&
1522 	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1523 	    pmc->sfcount[MCAST_INCLUDE]) {
1524 #ifdef CONFIG_IP_MULTICAST
1525 		struct ip_sf_list *psf;
1526 #endif
1527 
1528 		/* filter mode change */
1529 		pmc->sfmode = MCAST_INCLUDE;
1530 #ifdef CONFIG_IP_MULTICAST
1531 		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1532 			IGMP_Unsolicited_Report_Count;
1533 		in_dev->mr_ifc_count = pmc->crcount;
1534 		for (psf=pmc->sources; psf; psf = psf->sf_next)
1535 			psf->sf_crcount = 0;
1536 		igmp_ifc_event(pmc->interface);
1537 	} else if (sf_setstate(pmc) || changerec) {
1538 		igmp_ifc_event(pmc->interface);
1539 #endif
1540 	}
1541 out_unlock:
1542 	spin_unlock_bh(&pmc->lock);
1543 	return err;
1544 }
1545 
1546 /*
1547  * Add multicast single-source filter to the interface list
1548  */
1549 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1550 	__be32 *psfsrc, int delta)
1551 {
1552 	struct ip_sf_list *psf, *psf_prev;
1553 
1554 	psf_prev = NULL;
1555 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1556 		if (psf->sf_inaddr == *psfsrc)
1557 			break;
1558 		psf_prev = psf;
1559 	}
1560 	if (!psf) {
1561 		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1562 		if (!psf)
1563 			return -ENOBUFS;
1564 		psf->sf_inaddr = *psfsrc;
1565 		if (psf_prev) {
1566 			psf_prev->sf_next = psf;
1567 		} else
1568 			pmc->sources = psf;
1569 	}
1570 	psf->sf_count[sfmode]++;
1571 	if (psf->sf_count[sfmode] == 1) {
1572 		ip_rt_multicast_event(pmc->interface);
1573 	}
1574 	return 0;
1575 }
1576 
1577 #ifdef CONFIG_IP_MULTICAST
1578 static void sf_markstate(struct ip_mc_list *pmc)
1579 {
1580 	struct ip_sf_list *psf;
1581 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1582 
1583 	for (psf=pmc->sources; psf; psf=psf->sf_next)
1584 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1585 			psf->sf_oldin = mca_xcount ==
1586 				psf->sf_count[MCAST_EXCLUDE] &&
1587 				!psf->sf_count[MCAST_INCLUDE];
1588 		} else
1589 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1590 }
1591 
1592 static int sf_setstate(struct ip_mc_list *pmc)
1593 {
1594 	struct ip_sf_list *psf, *dpsf;
1595 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1596 	int qrv = pmc->interface->mr_qrv;
1597 	int new_in, rv;
1598 
1599 	rv = 0;
1600 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1601 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1602 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1603 				!psf->sf_count[MCAST_INCLUDE];
1604 		} else
1605 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1606 		if (new_in) {
1607 			if (!psf->sf_oldin) {
1608 				struct ip_sf_list *prev = NULL;
1609 
1610 				for (dpsf=pmc->tomb; dpsf; dpsf=dpsf->sf_next) {
1611 					if (dpsf->sf_inaddr == psf->sf_inaddr)
1612 						break;
1613 					prev = dpsf;
1614 				}
1615 				if (dpsf) {
1616 					if (prev)
1617 						prev->sf_next = dpsf->sf_next;
1618 					else
1619 						pmc->tomb = dpsf->sf_next;
1620 					kfree(dpsf);
1621 				}
1622 				psf->sf_crcount = qrv;
1623 				rv++;
1624 			}
1625 		} else if (psf->sf_oldin) {
1626 
1627 			psf->sf_crcount = 0;
1628 			/*
1629 			 * add or update "delete" records if an active filter
1630 			 * is now inactive
1631 			 */
1632 			for (dpsf=pmc->tomb; dpsf; dpsf=dpsf->sf_next)
1633 				if (dpsf->sf_inaddr == psf->sf_inaddr)
1634 					break;
1635 			if (!dpsf) {
1636 				dpsf = (struct ip_sf_list *)
1637 					kmalloc(sizeof(*dpsf), GFP_ATOMIC);
1638 				if (!dpsf)
1639 					continue;
1640 				*dpsf = *psf;
1641 				/* pmc->lock held by callers */
1642 				dpsf->sf_next = pmc->tomb;
1643 				pmc->tomb = dpsf;
1644 			}
1645 			dpsf->sf_crcount = qrv;
1646 			rv++;
1647 		}
1648 	}
1649 	return rv;
1650 }
1651 #endif
1652 
1653 /*
1654  * Add multicast source filter list to the interface list
1655  */
1656 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1657 			 int sfcount, __be32 *psfsrc, int delta)
1658 {
1659 	struct ip_mc_list *pmc;
1660 	int	isexclude;
1661 	int	i, err;
1662 
1663 	if (!in_dev)
1664 		return -ENODEV;
1665 	read_lock(&in_dev->mc_list_lock);
1666 	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1667 		if (*pmca == pmc->multiaddr)
1668 			break;
1669 	}
1670 	if (!pmc) {
1671 		/* MCA not found?? bug */
1672 		read_unlock(&in_dev->mc_list_lock);
1673 		return -ESRCH;
1674 	}
1675 	spin_lock_bh(&pmc->lock);
1676 	read_unlock(&in_dev->mc_list_lock);
1677 
1678 #ifdef CONFIG_IP_MULTICAST
1679 	sf_markstate(pmc);
1680 #endif
1681 	isexclude = pmc->sfmode == MCAST_EXCLUDE;
1682 	if (!delta)
1683 		pmc->sfcount[sfmode]++;
1684 	err = 0;
1685 	for (i=0; i<sfcount; i++) {
1686 		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i], delta);
1687 		if (err)
1688 			break;
1689 	}
1690 	if (err) {
1691 		int j;
1692 
1693 		pmc->sfcount[sfmode]--;
1694 		for (j=0; j<i; j++)
1695 			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1696 	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
1697 #ifdef CONFIG_IP_MULTICAST
1698 		struct ip_sf_list *psf;
1699 		in_dev = pmc->interface;
1700 #endif
1701 
1702 		/* filter mode change */
1703 		if (pmc->sfcount[MCAST_EXCLUDE])
1704 			pmc->sfmode = MCAST_EXCLUDE;
1705 		else if (pmc->sfcount[MCAST_INCLUDE])
1706 			pmc->sfmode = MCAST_INCLUDE;
1707 #ifdef CONFIG_IP_MULTICAST
1708 		/* else no filters; keep old mode for reports */
1709 
1710 		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1711 			IGMP_Unsolicited_Report_Count;
1712 		in_dev->mr_ifc_count = pmc->crcount;
1713 		for (psf=pmc->sources; psf; psf = psf->sf_next)
1714 			psf->sf_crcount = 0;
1715 		igmp_ifc_event(in_dev);
1716 	} else if (sf_setstate(pmc)) {
1717 		igmp_ifc_event(in_dev);
1718 #endif
1719 	}
1720 	spin_unlock_bh(&pmc->lock);
1721 	return err;
1722 }
1723 
1724 static void ip_mc_clear_src(struct ip_mc_list *pmc)
1725 {
1726 	struct ip_sf_list *psf, *nextpsf;
1727 
1728 	for (psf=pmc->tomb; psf; psf=nextpsf) {
1729 		nextpsf = psf->sf_next;
1730 		kfree(psf);
1731 	}
1732 	pmc->tomb = NULL;
1733 	for (psf=pmc->sources; psf; psf=nextpsf) {
1734 		nextpsf = psf->sf_next;
1735 		kfree(psf);
1736 	}
1737 	pmc->sources = NULL;
1738 	pmc->sfmode = MCAST_EXCLUDE;
1739 	pmc->sfcount[MCAST_INCLUDE] = 0;
1740 	pmc->sfcount[MCAST_EXCLUDE] = 1;
1741 }
1742 
1743 
1744 /*
1745  * Join a multicast group
1746  */
1747 int ip_mc_join_group(struct sock *sk , struct ip_mreqn *imr)
1748 {
1749 	int err;
1750 	__be32 addr = imr->imr_multiaddr.s_addr;
1751 	struct ip_mc_socklist *iml=NULL, *i;
1752 	struct in_device *in_dev;
1753 	struct inet_sock *inet = inet_sk(sk);
1754 	int ifindex;
1755 	int count = 0;
1756 
1757 	if (!MULTICAST(addr))
1758 		return -EINVAL;
1759 
1760 	rtnl_lock();
1761 
1762 	in_dev = ip_mc_find_dev(imr);
1763 
1764 	if (!in_dev) {
1765 		iml = NULL;
1766 		err = -ENODEV;
1767 		goto done;
1768 	}
1769 
1770 	err = -EADDRINUSE;
1771 	ifindex = imr->imr_ifindex;
1772 	for (i = inet->mc_list; i; i = i->next) {
1773 		if (i->multi.imr_multiaddr.s_addr == addr &&
1774 		    i->multi.imr_ifindex == ifindex)
1775 			goto done;
1776 		count++;
1777 	}
1778 	err = -ENOBUFS;
1779 	if (count >= sysctl_igmp_max_memberships)
1780 		goto done;
1781 	iml = sock_kmalloc(sk,sizeof(*iml),GFP_KERNEL);
1782 	if (iml == NULL)
1783 		goto done;
1784 
1785 	memcpy(&iml->multi, imr, sizeof(*imr));
1786 	iml->next = inet->mc_list;
1787 	iml->sflist = NULL;
1788 	iml->sfmode = MCAST_EXCLUDE;
1789 	inet->mc_list = iml;
1790 	ip_mc_inc_group(in_dev, addr);
1791 	err = 0;
1792 done:
1793 	rtnl_unlock();
1794 	return err;
1795 }
1796 
1797 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
1798 			   struct in_device *in_dev)
1799 {
1800 	int err;
1801 
1802 	if (iml->sflist == NULL) {
1803 		/* any-source empty exclude case */
1804 		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1805 			iml->sfmode, 0, NULL, 0);
1806 	}
1807 	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1808 			iml->sfmode, iml->sflist->sl_count,
1809 			iml->sflist->sl_addr, 0);
1810 	sock_kfree_s(sk, iml->sflist, IP_SFLSIZE(iml->sflist->sl_max));
1811 	iml->sflist = NULL;
1812 	return err;
1813 }
1814 
1815 /*
1816  *	Ask a socket to leave a group.
1817  */
1818 
1819 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
1820 {
1821 	struct inet_sock *inet = inet_sk(sk);
1822 	struct ip_mc_socklist *iml, **imlp;
1823 	struct in_device *in_dev;
1824 	__be32 group = imr->imr_multiaddr.s_addr;
1825 	u32 ifindex;
1826 	int ret = -EADDRNOTAVAIL;
1827 
1828 	rtnl_lock();
1829 	in_dev = ip_mc_find_dev(imr);
1830 	ifindex = imr->imr_ifindex;
1831 	for (imlp = &inet->mc_list; (iml = *imlp) != NULL; imlp = &iml->next) {
1832 		if (iml->multi.imr_multiaddr.s_addr != group)
1833 			continue;
1834 		if (ifindex) {
1835 			if (iml->multi.imr_ifindex != ifindex)
1836 				continue;
1837 		} else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
1838 				iml->multi.imr_address.s_addr)
1839 			continue;
1840 
1841 		(void) ip_mc_leave_src(sk, iml, in_dev);
1842 
1843 		*imlp = iml->next;
1844 
1845 		if (in_dev)
1846 			ip_mc_dec_group(in_dev, group);
1847 		rtnl_unlock();
1848 		sock_kfree_s(sk, iml, sizeof(*iml));
1849 		return 0;
1850 	}
1851 	if (!in_dev)
1852 		ret = -ENODEV;
1853 	rtnl_unlock();
1854 	return ret;
1855 }
1856 
1857 int ip_mc_source(int add, int omode, struct sock *sk, struct
1858 	ip_mreq_source *mreqs, int ifindex)
1859 {
1860 	int err;
1861 	struct ip_mreqn imr;
1862 	__be32 addr = mreqs->imr_multiaddr;
1863 	struct ip_mc_socklist *pmc;
1864 	struct in_device *in_dev = NULL;
1865 	struct inet_sock *inet = inet_sk(sk);
1866 	struct ip_sf_socklist *psl;
1867 	int leavegroup = 0;
1868 	int i, j, rv;
1869 
1870 	if (!MULTICAST(addr))
1871 		return -EINVAL;
1872 
1873 	rtnl_lock();
1874 
1875 	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
1876 	imr.imr_address.s_addr = mreqs->imr_interface;
1877 	imr.imr_ifindex = ifindex;
1878 	in_dev = ip_mc_find_dev(&imr);
1879 
1880 	if (!in_dev) {
1881 		err = -ENODEV;
1882 		goto done;
1883 	}
1884 	err = -EADDRNOTAVAIL;
1885 
1886 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
1887 		if (pmc->multi.imr_multiaddr.s_addr == imr.imr_multiaddr.s_addr
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 a source filter was set, must be the same mode as before */
1896 	if (pmc->sflist) {
1897 		if (pmc->sfmode != omode) {
1898 			err = -EINVAL;
1899 			goto done;
1900 		}
1901 	} else if (pmc->sfmode != omode) {
1902 		/* allow mode switches for empty-set filters */
1903 		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
1904 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
1905 			NULL, 0);
1906 		pmc->sfmode = omode;
1907 	}
1908 
1909 	psl = pmc->sflist;
1910 	if (!add) {
1911 		if (!psl)
1912 			goto done;	/* err = -EADDRNOTAVAIL */
1913 		rv = !0;
1914 		for (i=0; i<psl->sl_count; i++) {
1915 			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1916 				sizeof(__be32));
1917 			if (rv == 0)
1918 				break;
1919 		}
1920 		if (rv)		/* source not found */
1921 			goto done;	/* err = -EADDRNOTAVAIL */
1922 
1923 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
1924 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
1925 			leavegroup = 1;
1926 			goto done;
1927 		}
1928 
1929 		/* update the interface filter */
1930 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1931 			&mreqs->imr_sourceaddr, 1);
1932 
1933 		for (j=i+1; j<psl->sl_count; j++)
1934 			psl->sl_addr[j-1] = psl->sl_addr[j];
1935 		psl->sl_count--;
1936 		err = 0;
1937 		goto done;
1938 	}
1939 	/* else, add a new source to the filter */
1940 
1941 	if (psl && psl->sl_count >= sysctl_igmp_max_msf) {
1942 		err = -ENOBUFS;
1943 		goto done;
1944 	}
1945 	if (!psl || psl->sl_count == psl->sl_max) {
1946 		struct ip_sf_socklist *newpsl;
1947 		int count = IP_SFBLOCK;
1948 
1949 		if (psl)
1950 			count += psl->sl_max;
1951 		newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
1952 		if (!newpsl) {
1953 			err = -ENOBUFS;
1954 			goto done;
1955 		}
1956 		newpsl->sl_max = count;
1957 		newpsl->sl_count = count - IP_SFBLOCK;
1958 		if (psl) {
1959 			for (i=0; i<psl->sl_count; i++)
1960 				newpsl->sl_addr[i] = psl->sl_addr[i];
1961 			sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
1962 		}
1963 		pmc->sflist = psl = newpsl;
1964 	}
1965 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
1966 	for (i=0; i<psl->sl_count; i++) {
1967 		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1968 			sizeof(__be32));
1969 		if (rv == 0)
1970 			break;
1971 	}
1972 	if (rv == 0)		/* address already there is an error */
1973 		goto done;
1974 	for (j=psl->sl_count-1; j>=i; j--)
1975 		psl->sl_addr[j+1] = psl->sl_addr[j];
1976 	psl->sl_addr[i] = mreqs->imr_sourceaddr;
1977 	psl->sl_count++;
1978 	err = 0;
1979 	/* update the interface list */
1980 	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1981 		&mreqs->imr_sourceaddr, 1);
1982 done:
1983 	rtnl_unlock();
1984 	if (leavegroup)
1985 		return ip_mc_leave_group(sk, &imr);
1986 	return err;
1987 }
1988 
1989 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
1990 {
1991 	int err = 0;
1992 	struct ip_mreqn	imr;
1993 	__be32 addr = msf->imsf_multiaddr;
1994 	struct ip_mc_socklist *pmc;
1995 	struct in_device *in_dev;
1996 	struct inet_sock *inet = inet_sk(sk);
1997 	struct ip_sf_socklist *newpsl, *psl;
1998 	int leavegroup = 0;
1999 
2000 	if (!MULTICAST(addr))
2001 		return -EINVAL;
2002 	if (msf->imsf_fmode != MCAST_INCLUDE &&
2003 	    msf->imsf_fmode != MCAST_EXCLUDE)
2004 		return -EINVAL;
2005 
2006 	rtnl_lock();
2007 
2008 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2009 	imr.imr_address.s_addr = msf->imsf_interface;
2010 	imr.imr_ifindex = ifindex;
2011 	in_dev = ip_mc_find_dev(&imr);
2012 
2013 	if (!in_dev) {
2014 		err = -ENODEV;
2015 		goto done;
2016 	}
2017 
2018 	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2019 	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2020 		leavegroup = 1;
2021 		goto done;
2022 	}
2023 
2024 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2025 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2026 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2027 			break;
2028 	}
2029 	if (!pmc) {		/* must have a prior join */
2030 		err = -EINVAL;
2031 		goto done;
2032 	}
2033 	if (msf->imsf_numsrc) {
2034 		newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2035 							   GFP_KERNEL);
2036 		if (!newpsl) {
2037 			err = -ENOBUFS;
2038 			goto done;
2039 		}
2040 		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2041 		memcpy(newpsl->sl_addr, msf->imsf_slist,
2042 			msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2043 		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2044 			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2045 		if (err) {
2046 			sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2047 			goto done;
2048 		}
2049 	} else {
2050 		newpsl = NULL;
2051 		(void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2052 				     msf->imsf_fmode, 0, NULL, 0);
2053 	}
2054 	psl = pmc->sflist;
2055 	if (psl) {
2056 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2057 			psl->sl_count, psl->sl_addr, 0);
2058 		sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
2059 	} else
2060 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2061 			0, NULL, 0);
2062 	pmc->sflist = newpsl;
2063 	pmc->sfmode = msf->imsf_fmode;
2064 	err = 0;
2065 done:
2066 	rtnl_unlock();
2067 	if (leavegroup)
2068 		err = ip_mc_leave_group(sk, &imr);
2069 	return err;
2070 }
2071 
2072 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2073 	struct ip_msfilter __user *optval, int __user *optlen)
2074 {
2075 	int err, len, count, copycount;
2076 	struct ip_mreqn	imr;
2077 	__be32 addr = msf->imsf_multiaddr;
2078 	struct ip_mc_socklist *pmc;
2079 	struct in_device *in_dev;
2080 	struct inet_sock *inet = inet_sk(sk);
2081 	struct ip_sf_socklist *psl;
2082 
2083 	if (!MULTICAST(addr))
2084 		return -EINVAL;
2085 
2086 	rtnl_lock();
2087 
2088 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2089 	imr.imr_address.s_addr = msf->imsf_interface;
2090 	imr.imr_ifindex = 0;
2091 	in_dev = ip_mc_find_dev(&imr);
2092 
2093 	if (!in_dev) {
2094 		err = -ENODEV;
2095 		goto done;
2096 	}
2097 	err = -EADDRNOTAVAIL;
2098 
2099 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2100 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2101 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2102 			break;
2103 	}
2104 	if (!pmc)		/* must have a prior join */
2105 		goto done;
2106 	msf->imsf_fmode = pmc->sfmode;
2107 	psl = pmc->sflist;
2108 	rtnl_unlock();
2109 	if (!psl) {
2110 		len = 0;
2111 		count = 0;
2112 	} else {
2113 		count = psl->sl_count;
2114 	}
2115 	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2116 	len = copycount * sizeof(psl->sl_addr[0]);
2117 	msf->imsf_numsrc = count;
2118 	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2119 	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2120 		return -EFAULT;
2121 	}
2122 	if (len &&
2123 	    copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2124 		return -EFAULT;
2125 	return 0;
2126 done:
2127 	rtnl_unlock();
2128 	return err;
2129 }
2130 
2131 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2132 	struct group_filter __user *optval, int __user *optlen)
2133 {
2134 	int err, i, count, copycount;
2135 	struct sockaddr_in *psin;
2136 	__be32 addr;
2137 	struct ip_mc_socklist *pmc;
2138 	struct inet_sock *inet = inet_sk(sk);
2139 	struct ip_sf_socklist *psl;
2140 
2141 	psin = (struct sockaddr_in *)&gsf->gf_group;
2142 	if (psin->sin_family != AF_INET)
2143 		return -EINVAL;
2144 	addr = psin->sin_addr.s_addr;
2145 	if (!MULTICAST(addr))
2146 		return -EINVAL;
2147 
2148 	rtnl_lock();
2149 
2150 	err = -EADDRNOTAVAIL;
2151 
2152 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2153 		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2154 		    pmc->multi.imr_ifindex == gsf->gf_interface)
2155 			break;
2156 	}
2157 	if (!pmc)		/* must have a prior join */
2158 		goto done;
2159 	gsf->gf_fmode = pmc->sfmode;
2160 	psl = pmc->sflist;
2161 	rtnl_unlock();
2162 	count = psl ? psl->sl_count : 0;
2163 	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2164 	gsf->gf_numsrc = count;
2165 	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2166 	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2167 		return -EFAULT;
2168 	}
2169 	for (i=0; i<copycount; i++) {
2170 		struct sockaddr_storage ss;
2171 
2172 		psin = (struct sockaddr_in *)&ss;
2173 		memset(&ss, 0, sizeof(ss));
2174 		psin->sin_family = AF_INET;
2175 		psin->sin_addr.s_addr = psl->sl_addr[i];
2176 		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2177 			return -EFAULT;
2178 	}
2179 	return 0;
2180 done:
2181 	rtnl_unlock();
2182 	return err;
2183 }
2184 
2185 /*
2186  * check if a multicast source filter allows delivery for a given <src,dst,intf>
2187  */
2188 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif)
2189 {
2190 	struct inet_sock *inet = inet_sk(sk);
2191 	struct ip_mc_socklist *pmc;
2192 	struct ip_sf_socklist *psl;
2193 	int i;
2194 
2195 	if (!MULTICAST(loc_addr))
2196 		return 1;
2197 
2198 	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2199 		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2200 		    pmc->multi.imr_ifindex == dif)
2201 			break;
2202 	}
2203 	if (!pmc)
2204 		return 1;
2205 	psl = pmc->sflist;
2206 	if (!psl)
2207 		return pmc->sfmode == MCAST_EXCLUDE;
2208 
2209 	for (i=0; i<psl->sl_count; i++) {
2210 		if (psl->sl_addr[i] == rmt_addr)
2211 			break;
2212 	}
2213 	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2214 		return 0;
2215 	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2216 		return 0;
2217 	return 1;
2218 }
2219 
2220 /*
2221  *	A socket is closing.
2222  */
2223 
2224 void ip_mc_drop_socket(struct sock *sk)
2225 {
2226 	struct inet_sock *inet = inet_sk(sk);
2227 	struct ip_mc_socklist *iml;
2228 
2229 	if (inet->mc_list == NULL)
2230 		return;
2231 
2232 	rtnl_lock();
2233 	while ((iml = inet->mc_list) != NULL) {
2234 		struct in_device *in_dev;
2235 		inet->mc_list = iml->next;
2236 
2237 		in_dev = inetdev_by_index(iml->multi.imr_ifindex);
2238 		(void) ip_mc_leave_src(sk, iml, in_dev);
2239 		if (in_dev != NULL) {
2240 			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2241 			in_dev_put(in_dev);
2242 		}
2243 		sock_kfree_s(sk, iml, sizeof(*iml));
2244 	}
2245 	rtnl_unlock();
2246 }
2247 
2248 int ip_check_mc(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u16 proto)
2249 {
2250 	struct ip_mc_list *im;
2251 	struct ip_sf_list *psf;
2252 	int rv = 0;
2253 
2254 	read_lock(&in_dev->mc_list_lock);
2255 	for (im=in_dev->mc_list; im; im=im->next) {
2256 		if (im->multiaddr == mc_addr)
2257 			break;
2258 	}
2259 	if (im && proto == IPPROTO_IGMP) {
2260 		rv = 1;
2261 	} else if (im) {
2262 		if (src_addr) {
2263 			for (psf=im->sources; psf; psf=psf->sf_next) {
2264 				if (psf->sf_inaddr == src_addr)
2265 					break;
2266 			}
2267 			if (psf)
2268 				rv = psf->sf_count[MCAST_INCLUDE] ||
2269 					psf->sf_count[MCAST_EXCLUDE] !=
2270 					im->sfcount[MCAST_EXCLUDE];
2271 			else
2272 				rv = im->sfcount[MCAST_EXCLUDE] != 0;
2273 		} else
2274 			rv = 1; /* unspecified source; tentatively allow */
2275 	}
2276 	read_unlock(&in_dev->mc_list_lock);
2277 	return rv;
2278 }
2279 
2280 #if defined(CONFIG_PROC_FS)
2281 struct igmp_mc_iter_state {
2282 	struct net_device *dev;
2283 	struct in_device *in_dev;
2284 };
2285 
2286 #define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2287 
2288 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2289 {
2290 	struct ip_mc_list *im = NULL;
2291 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2292 
2293 	state->in_dev = NULL;
2294 	for_each_netdev(&init_net, state->dev) {
2295 		struct in_device *in_dev;
2296 		in_dev = in_dev_get(state->dev);
2297 		if (!in_dev)
2298 			continue;
2299 		read_lock(&in_dev->mc_list_lock);
2300 		im = in_dev->mc_list;
2301 		if (im) {
2302 			state->in_dev = in_dev;
2303 			break;
2304 		}
2305 		read_unlock(&in_dev->mc_list_lock);
2306 		in_dev_put(in_dev);
2307 	}
2308 	return im;
2309 }
2310 
2311 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2312 {
2313 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2314 	im = im->next;
2315 	while (!im) {
2316 		if (likely(state->in_dev != NULL)) {
2317 			read_unlock(&state->in_dev->mc_list_lock);
2318 			in_dev_put(state->in_dev);
2319 		}
2320 		state->dev = next_net_device(state->dev);
2321 		if (!state->dev) {
2322 			state->in_dev = NULL;
2323 			break;
2324 		}
2325 		state->in_dev = in_dev_get(state->dev);
2326 		if (!state->in_dev)
2327 			continue;
2328 		read_lock(&state->in_dev->mc_list_lock);
2329 		im = state->in_dev->mc_list;
2330 	}
2331 	return im;
2332 }
2333 
2334 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2335 {
2336 	struct ip_mc_list *im = igmp_mc_get_first(seq);
2337 	if (im)
2338 		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2339 			--pos;
2340 	return pos ? NULL : im;
2341 }
2342 
2343 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2344 {
2345 	read_lock(&dev_base_lock);
2346 	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2347 }
2348 
2349 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2350 {
2351 	struct ip_mc_list *im;
2352 	if (v == SEQ_START_TOKEN)
2353 		im = igmp_mc_get_first(seq);
2354 	else
2355 		im = igmp_mc_get_next(seq, v);
2356 	++*pos;
2357 	return im;
2358 }
2359 
2360 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2361 {
2362 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2363 	if (likely(state->in_dev != NULL)) {
2364 		read_unlock(&state->in_dev->mc_list_lock);
2365 		in_dev_put(state->in_dev);
2366 		state->in_dev = NULL;
2367 	}
2368 	state->dev = NULL;
2369 	read_unlock(&dev_base_lock);
2370 }
2371 
2372 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2373 {
2374 	if (v == SEQ_START_TOKEN)
2375 		seq_puts(seq,
2376 			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2377 	else {
2378 		struct ip_mc_list *im = (struct ip_mc_list *)v;
2379 		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2380 		char   *querier;
2381 #ifdef CONFIG_IP_MULTICAST
2382 		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2383 			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2384 			  "V3";
2385 #else
2386 		querier = "NONE";
2387 #endif
2388 
2389 		if (state->in_dev->mc_list == im) {
2390 			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2391 				   state->dev->ifindex, state->dev->name, state->dev->mc_count, querier);
2392 		}
2393 
2394 		seq_printf(seq,
2395 			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2396 			   im->multiaddr, im->users,
2397 			   im->tm_running, im->tm_running ?
2398 			   jiffies_to_clock_t(im->timer.expires-jiffies) : 0,
2399 			   im->reporter);
2400 	}
2401 	return 0;
2402 }
2403 
2404 static const struct seq_operations igmp_mc_seq_ops = {
2405 	.start	=	igmp_mc_seq_start,
2406 	.next	=	igmp_mc_seq_next,
2407 	.stop	=	igmp_mc_seq_stop,
2408 	.show	=	igmp_mc_seq_show,
2409 };
2410 
2411 static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2412 {
2413 	return seq_open_private(file, &igmp_mc_seq_ops,
2414 			sizeof(struct igmp_mc_iter_state));
2415 }
2416 
2417 static const struct file_operations igmp_mc_seq_fops = {
2418 	.owner		=	THIS_MODULE,
2419 	.open		=	igmp_mc_seq_open,
2420 	.read		=	seq_read,
2421 	.llseek		=	seq_lseek,
2422 	.release	=	seq_release_private,
2423 };
2424 
2425 struct igmp_mcf_iter_state {
2426 	struct net_device *dev;
2427 	struct in_device *idev;
2428 	struct ip_mc_list *im;
2429 };
2430 
2431 #define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2432 
2433 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2434 {
2435 	struct ip_sf_list *psf = NULL;
2436 	struct ip_mc_list *im = NULL;
2437 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2438 
2439 	state->idev = NULL;
2440 	state->im = NULL;
2441 	for_each_netdev(&init_net, state->dev) {
2442 		struct in_device *idev;
2443 		idev = in_dev_get(state->dev);
2444 		if (unlikely(idev == NULL))
2445 			continue;
2446 		read_lock(&idev->mc_list_lock);
2447 		im = idev->mc_list;
2448 		if (likely(im != NULL)) {
2449 			spin_lock_bh(&im->lock);
2450 			psf = im->sources;
2451 			if (likely(psf != NULL)) {
2452 				state->im = im;
2453 				state->idev = idev;
2454 				break;
2455 			}
2456 			spin_unlock_bh(&im->lock);
2457 		}
2458 		read_unlock(&idev->mc_list_lock);
2459 		in_dev_put(idev);
2460 	}
2461 	return psf;
2462 }
2463 
2464 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2465 {
2466 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2467 
2468 	psf = psf->sf_next;
2469 	while (!psf) {
2470 		spin_unlock_bh(&state->im->lock);
2471 		state->im = state->im->next;
2472 		while (!state->im) {
2473 			if (likely(state->idev != NULL)) {
2474 				read_unlock(&state->idev->mc_list_lock);
2475 				in_dev_put(state->idev);
2476 			}
2477 			state->dev = next_net_device(state->dev);
2478 			if (!state->dev) {
2479 				state->idev = NULL;
2480 				goto out;
2481 			}
2482 			state->idev = in_dev_get(state->dev);
2483 			if (!state->idev)
2484 				continue;
2485 			read_lock(&state->idev->mc_list_lock);
2486 			state->im = state->idev->mc_list;
2487 		}
2488 		if (!state->im)
2489 			break;
2490 		spin_lock_bh(&state->im->lock);
2491 		psf = state->im->sources;
2492 	}
2493 out:
2494 	return psf;
2495 }
2496 
2497 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2498 {
2499 	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2500 	if (psf)
2501 		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2502 			--pos;
2503 	return pos ? NULL : psf;
2504 }
2505 
2506 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2507 {
2508 	read_lock(&dev_base_lock);
2509 	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2510 }
2511 
2512 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2513 {
2514 	struct ip_sf_list *psf;
2515 	if (v == SEQ_START_TOKEN)
2516 		psf = igmp_mcf_get_first(seq);
2517 	else
2518 		psf = igmp_mcf_get_next(seq, v);
2519 	++*pos;
2520 	return psf;
2521 }
2522 
2523 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2524 {
2525 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2526 	if (likely(state->im != NULL)) {
2527 		spin_unlock_bh(&state->im->lock);
2528 		state->im = NULL;
2529 	}
2530 	if (likely(state->idev != NULL)) {
2531 		read_unlock(&state->idev->mc_list_lock);
2532 		in_dev_put(state->idev);
2533 		state->idev = NULL;
2534 	}
2535 	state->dev = NULL;
2536 	read_unlock(&dev_base_lock);
2537 }
2538 
2539 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2540 {
2541 	struct ip_sf_list *psf = (struct ip_sf_list *)v;
2542 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2543 
2544 	if (v == SEQ_START_TOKEN) {
2545 		seq_printf(seq,
2546 			   "%3s %6s "
2547 			   "%10s %10s %6s %6s\n", "Idx",
2548 			   "Device", "MCA",
2549 			   "SRC", "INC", "EXC");
2550 	} else {
2551 		seq_printf(seq,
2552 			   "%3d %6.6s 0x%08x "
2553 			   "0x%08x %6lu %6lu\n",
2554 			   state->dev->ifindex, state->dev->name,
2555 			   ntohl(state->im->multiaddr),
2556 			   ntohl(psf->sf_inaddr),
2557 			   psf->sf_count[MCAST_INCLUDE],
2558 			   psf->sf_count[MCAST_EXCLUDE]);
2559 	}
2560 	return 0;
2561 }
2562 
2563 static const struct seq_operations igmp_mcf_seq_ops = {
2564 	.start	=	igmp_mcf_seq_start,
2565 	.next	=	igmp_mcf_seq_next,
2566 	.stop	=	igmp_mcf_seq_stop,
2567 	.show	=	igmp_mcf_seq_show,
2568 };
2569 
2570 static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2571 {
2572 	return seq_open_private(file, &igmp_mcf_seq_ops,
2573 			sizeof(struct igmp_mcf_iter_state));
2574 }
2575 
2576 static const struct file_operations igmp_mcf_seq_fops = {
2577 	.owner		=	THIS_MODULE,
2578 	.open		=	igmp_mcf_seq_open,
2579 	.read		=	seq_read,
2580 	.llseek		=	seq_lseek,
2581 	.release	=	seq_release_private,
2582 };
2583 
2584 int __init igmp_mc_proc_init(void)
2585 {
2586 	proc_net_fops_create(&init_net, "igmp", S_IRUGO, &igmp_mc_seq_fops);
2587 	proc_net_fops_create(&init_net, "mcfilter", S_IRUGO, &igmp_mcf_seq_fops);
2588 	return 0;
2589 }
2590 #endif
2591 
2592 EXPORT_SYMBOL(ip_mc_dec_group);
2593 EXPORT_SYMBOL(ip_mc_inc_group);
2594 EXPORT_SYMBOL(ip_mc_join_group);
2595 EXPORT_SYMBOL(ip_mc_rejoin_group);
2596