xref: /linux/net/ipv4/igmp.c (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
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  *	Authors:
12  *		Alan Cox <alan@lxorguk.ukuu.org.uk>
13  *
14  *	This program is free software; you can redistribute it and/or
15  *	modify it under the terms of the GNU General Public License
16  *	as published by the Free Software Foundation; either version
17  *	2 of the License, or (at your option) any later version.
18  *
19  *	Fixes:
20  *
21  *		Alan Cox	:	Added lots of __inline__ to optimise
22  *					the memory usage of all the tiny little
23  *					functions.
24  *		Alan Cox	:	Dumped the header building experiment.
25  *		Alan Cox	:	Minor tweaks ready for multicast routing
26  *					and extended IGMP protocol.
27  *		Alan Cox	:	Removed a load of inline directives. Gcc 2.5.8
28  *					writes utterly bogus code otherwise (sigh)
29  *					fixed IGMP loopback to behave in the manner
30  *					desired by mrouted, fixed the fact it has been
31  *					broken since 1.3.6 and cleaned up a few minor
32  *					points.
33  *
34  *		Chih-Jen Chang	:	Tried to revise IGMP to Version 2
35  *		Tsu-Sheng Tsao		E-mail: chihjenc@scf.usc.edu and tsusheng@scf.usc.edu
36  *					The enhancements are mainly based on Steve Deering's
37  * 					ipmulti-3.5 source code.
38  *		Chih-Jen Chang	:	Added the igmp_get_mrouter_info and
39  *		Tsu-Sheng Tsao		igmp_set_mrouter_info to keep track of
40  *					the mrouted version on that device.
41  *		Chih-Jen Chang	:	Added the max_resp_time parameter to
42  *		Tsu-Sheng Tsao		igmp_heard_query(). Using this parameter
43  *					to identify the multicast router version
44  *					and do what the IGMP version 2 specified.
45  *		Chih-Jen Chang	:	Added a timer to revert to IGMP V2 router
46  *		Tsu-Sheng Tsao		if the specified time expired.
47  *		Alan Cox	:	Stop IGMP from 0.0.0.0 being accepted.
48  *		Alan Cox	:	Use GFP_ATOMIC in the right places.
49  *		Christian Daudt :	igmp timer wasn't set for local group
50  *					memberships but was being deleted,
51  *					which caused a "del_timer() called
52  *					from %p with timer not initialized\n"
53  *					message (960131).
54  *		Christian Daudt :	removed del_timer from
55  *					igmp_timer_expire function (960205).
56  *             Christian Daudt :       igmp_heard_report now only calls
57  *                                     igmp_timer_expire if tm->running is
58  *                                     true (960216).
59  *		Malcolm Beattie :	ttl comparison wrong in igmp_rcv made
60  *					igmp_heard_query never trigger. Expiry
61  *					miscalculation fixed in igmp_heard_query
62  *					and random() made to return unsigned to
63  *					prevent negative expiry times.
64  *		Alexey Kuznetsov:	Wrong group leaving behaviour, backport
65  *					fix from pending 2.1.x patches.
66  *		Alan Cox:		Forget to enable FDDI support earlier.
67  *		Alexey Kuznetsov:	Fixed leaving groups on device down.
68  *		Alexey Kuznetsov:	Accordance to igmp-v2-06 draft.
69  *		David L Stevens:	IGMPv3 support, with help from
70  *					Vinay Kulkarni
71  */
72 
73 #include <linux/module.h>
74 #include <linux/slab.h>
75 #include <asm/uaccess.h>
76 #include <asm/system.h>
77 #include <linux/types.h>
78 #include <linux/kernel.h>
79 #include <linux/jiffies.h>
80 #include <linux/string.h>
81 #include <linux/socket.h>
82 #include <linux/sockios.h>
83 #include <linux/in.h>
84 #include <linux/inet.h>
85 #include <linux/netdevice.h>
86 #include <linux/skbuff.h>
87 #include <linux/inetdevice.h>
88 #include <linux/igmp.h>
89 #include <linux/if_arp.h>
90 #include <linux/rtnetlink.h>
91 #include <linux/times.h>
92 
93 #include <net/net_namespace.h>
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) \
132 	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \
133 	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \
134 	 ((in_dev)->mr_v1_seen && \
135 	  time_before(jiffies, (in_dev)->mr_v1_seen)))
136 #define IGMP_V2_SEEN(in_dev) \
137 	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \
138 	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \
139 	 ((in_dev)->mr_v2_seen && \
140 	  time_before(jiffies, (in_dev)->mr_v2_seen)))
141 
142 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im);
143 static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr);
144 static void igmpv3_clear_delrec(struct in_device *in_dev);
145 static int sf_setstate(struct ip_mc_list *pmc);
146 static void sf_markstate(struct ip_mc_list *pmc);
147 #endif
148 static void ip_mc_clear_src(struct ip_mc_list *pmc);
149 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
150 			 int sfcount, __be32 *psfsrc, int delta);
151 
152 static void ip_ma_put(struct ip_mc_list *im)
153 {
154 	if (atomic_dec_and_test(&im->refcnt)) {
155 		in_dev_put(im->interface);
156 		kfree_rcu(im, rcu);
157 	}
158 }
159 
160 #define for_each_pmc_rcu(in_dev, pmc)				\
161 	for (pmc = rcu_dereference(in_dev->mc_list);		\
162 	     pmc != NULL;					\
163 	     pmc = rcu_dereference(pmc->next_rcu))
164 
165 #define for_each_pmc_rtnl(in_dev, pmc)				\
166 	for (pmc = rtnl_dereference(in_dev->mc_list);		\
167 	     pmc != NULL;					\
168 	     pmc = rtnl_dereference(pmc->next_rcu))
169 
170 #ifdef CONFIG_IP_MULTICAST
171 
172 /*
173  *	Timer management
174  */
175 
176 static void igmp_stop_timer(struct ip_mc_list *im)
177 {
178 	spin_lock_bh(&im->lock);
179 	if (del_timer(&im->timer))
180 		atomic_dec(&im->refcnt);
181 	im->tm_running = 0;
182 	im->reporter = 0;
183 	im->unsolicit_count = 0;
184 	spin_unlock_bh(&im->lock);
185 }
186 
187 /* It must be called with locked im->lock */
188 static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
189 {
190 	int tv = net_random() % max_delay;
191 
192 	im->tm_running = 1;
193 	if (!mod_timer(&im->timer, jiffies+tv+2))
194 		atomic_inc(&im->refcnt);
195 }
196 
197 static void igmp_gq_start_timer(struct in_device *in_dev)
198 {
199 	int tv = net_random() % in_dev->mr_maxdelay;
200 
201 	in_dev->mr_gq_running = 1;
202 	if (!mod_timer(&in_dev->mr_gq_timer, jiffies+tv+2))
203 		in_dev_hold(in_dev);
204 }
205 
206 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
207 {
208 	int tv = net_random() % delay;
209 
210 	if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
211 		in_dev_hold(in_dev);
212 }
213 
214 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
215 {
216 	spin_lock_bh(&im->lock);
217 	im->unsolicit_count = 0;
218 	if (del_timer(&im->timer)) {
219 		if ((long)(im->timer.expires-jiffies) < max_delay) {
220 			add_timer(&im->timer);
221 			im->tm_running = 1;
222 			spin_unlock_bh(&im->lock);
223 			return;
224 		}
225 		atomic_dec(&im->refcnt);
226 	}
227 	igmp_start_timer(im, max_delay);
228 	spin_unlock_bh(&im->lock);
229 }
230 
231 
232 /*
233  *	Send an IGMP report.
234  */
235 
236 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
237 
238 
239 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
240 	int gdeleted, int sdeleted)
241 {
242 	switch (type) {
243 	case IGMPV3_MODE_IS_INCLUDE:
244 	case IGMPV3_MODE_IS_EXCLUDE:
245 		if (gdeleted || sdeleted)
246 			return 0;
247 		if (!(pmc->gsquery && !psf->sf_gsresp)) {
248 			if (pmc->sfmode == MCAST_INCLUDE)
249 				return 1;
250 			/* don't include if this source is excluded
251 			 * in all filters
252 			 */
253 			if (psf->sf_count[MCAST_INCLUDE])
254 				return type == IGMPV3_MODE_IS_INCLUDE;
255 			return pmc->sfcount[MCAST_EXCLUDE] ==
256 				psf->sf_count[MCAST_EXCLUDE];
257 		}
258 		return 0;
259 	case IGMPV3_CHANGE_TO_INCLUDE:
260 		if (gdeleted || sdeleted)
261 			return 0;
262 		return psf->sf_count[MCAST_INCLUDE] != 0;
263 	case IGMPV3_CHANGE_TO_EXCLUDE:
264 		if (gdeleted || sdeleted)
265 			return 0;
266 		if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
267 		    psf->sf_count[MCAST_INCLUDE])
268 			return 0;
269 		return pmc->sfcount[MCAST_EXCLUDE] ==
270 			psf->sf_count[MCAST_EXCLUDE];
271 	case IGMPV3_ALLOW_NEW_SOURCES:
272 		if (gdeleted || !psf->sf_crcount)
273 			return 0;
274 		return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
275 	case IGMPV3_BLOCK_OLD_SOURCES:
276 		if (pmc->sfmode == MCAST_INCLUDE)
277 			return gdeleted || (psf->sf_crcount && sdeleted);
278 		return psf->sf_crcount && !gdeleted && !sdeleted;
279 	}
280 	return 0;
281 }
282 
283 static int
284 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
285 {
286 	struct ip_sf_list *psf;
287 	int scount = 0;
288 
289 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
290 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
291 			continue;
292 		scount++;
293 	}
294 	return scount;
295 }
296 
297 #define igmp_skb_size(skb) (*(unsigned int *)((skb)->cb))
298 
299 static struct sk_buff *igmpv3_newpack(struct net_device *dev, int size)
300 {
301 	struct sk_buff *skb;
302 	struct rtable *rt;
303 	struct iphdr *pip;
304 	struct igmpv3_report *pig;
305 	struct net *net = dev_net(dev);
306 	struct flowi4 fl4;
307 
308 	while (1) {
309 		skb = alloc_skb(size + LL_ALLOCATED_SPACE(dev),
310 				GFP_ATOMIC | __GFP_NOWARN);
311 		if (skb)
312 			break;
313 		size >>= 1;
314 		if (size < 256)
315 			return NULL;
316 	}
317 	igmp_skb_size(skb) = size;
318 
319 	rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0,
320 				   0, 0,
321 				   IPPROTO_IGMP, 0, dev->ifindex);
322 	if (IS_ERR(rt)) {
323 		kfree_skb(skb);
324 		return NULL;
325 	}
326 
327 	skb_dst_set(skb, &rt->dst);
328 	skb->dev = dev;
329 
330 	skb_reserve(skb, LL_RESERVED_SPACE(dev));
331 
332 	skb_reset_network_header(skb);
333 	pip = ip_hdr(skb);
334 	skb_put(skb, sizeof(struct iphdr) + 4);
335 
336 	pip->version  = 4;
337 	pip->ihl      = (sizeof(struct iphdr)+4)>>2;
338 	pip->tos      = 0xc0;
339 	pip->frag_off = htons(IP_DF);
340 	pip->ttl      = 1;
341 	pip->daddr    = fl4.daddr;
342 	pip->saddr    = fl4.saddr;
343 	pip->protocol = IPPROTO_IGMP;
344 	pip->tot_len  = 0;	/* filled in later */
345 	ip_select_ident(pip, &rt->dst, NULL);
346 	((u8*)&pip[1])[0] = IPOPT_RA;
347 	((u8*)&pip[1])[1] = 4;
348 	((u8*)&pip[1])[2] = 0;
349 	((u8*)&pip[1])[3] = 0;
350 
351 	skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
352 	skb_put(skb, sizeof(*pig));
353 	pig = igmpv3_report_hdr(skb);
354 	pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
355 	pig->resv1 = 0;
356 	pig->csum = 0;
357 	pig->resv2 = 0;
358 	pig->ngrec = 0;
359 	return skb;
360 }
361 
362 static int igmpv3_sendpack(struct sk_buff *skb)
363 {
364 	struct igmphdr *pig = igmp_hdr(skb);
365 	const int igmplen = skb->tail - skb->transport_header;
366 
367 	pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
368 
369 	return ip_local_out(skb);
370 }
371 
372 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
373 {
374 	return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
375 }
376 
377 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
378 	int type, struct igmpv3_grec **ppgr)
379 {
380 	struct net_device *dev = pmc->interface->dev;
381 	struct igmpv3_report *pih;
382 	struct igmpv3_grec *pgr;
383 
384 	if (!skb)
385 		skb = igmpv3_newpack(dev, dev->mtu);
386 	if (!skb)
387 		return NULL;
388 	pgr = (struct igmpv3_grec *)skb_put(skb, sizeof(struct igmpv3_grec));
389 	pgr->grec_type = type;
390 	pgr->grec_auxwords = 0;
391 	pgr->grec_nsrcs = 0;
392 	pgr->grec_mca = pmc->multiaddr;
393 	pih = igmpv3_report_hdr(skb);
394 	pih->ngrec = htons(ntohs(pih->ngrec)+1);
395 	*ppgr = pgr;
396 	return skb;
397 }
398 
399 #define AVAILABLE(skb) ((skb) ? ((skb)->dev ? igmp_skb_size(skb) - (skb)->len : \
400 	skb_tailroom(skb)) : 0)
401 
402 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
403 	int type, int gdeleted, int sdeleted)
404 {
405 	struct net_device *dev = pmc->interface->dev;
406 	struct igmpv3_report *pih;
407 	struct igmpv3_grec *pgr = NULL;
408 	struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
409 	int scount, stotal, first, isquery, truncate;
410 
411 	if (pmc->multiaddr == IGMP_ALL_HOSTS)
412 		return skb;
413 
414 	isquery = type == IGMPV3_MODE_IS_INCLUDE ||
415 		  type == IGMPV3_MODE_IS_EXCLUDE;
416 	truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
417 		    type == IGMPV3_CHANGE_TO_EXCLUDE;
418 
419 	stotal = scount = 0;
420 
421 	psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
422 
423 	if (!*psf_list)
424 		goto empty_source;
425 
426 	pih = skb ? igmpv3_report_hdr(skb) : NULL;
427 
428 	/* EX and TO_EX get a fresh packet, if needed */
429 	if (truncate) {
430 		if (pih && pih->ngrec &&
431 		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
432 			if (skb)
433 				igmpv3_sendpack(skb);
434 			skb = igmpv3_newpack(dev, dev->mtu);
435 		}
436 	}
437 	first = 1;
438 	psf_prev = NULL;
439 	for (psf=*psf_list; psf; psf=psf_next) {
440 		__be32 *psrc;
441 
442 		psf_next = psf->sf_next;
443 
444 		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
445 			psf_prev = psf;
446 			continue;
447 		}
448 
449 		/* clear marks on query responses */
450 		if (isquery)
451 			psf->sf_gsresp = 0;
452 
453 		if (AVAILABLE(skb) < sizeof(__be32) +
454 		    first*sizeof(struct igmpv3_grec)) {
455 			if (truncate && !first)
456 				break;	 /* truncate these */
457 			if (pgr)
458 				pgr->grec_nsrcs = htons(scount);
459 			if (skb)
460 				igmpv3_sendpack(skb);
461 			skb = igmpv3_newpack(dev, dev->mtu);
462 			first = 1;
463 			scount = 0;
464 		}
465 		if (first) {
466 			skb = add_grhead(skb, pmc, type, &pgr);
467 			first = 0;
468 		}
469 		if (!skb)
470 			return NULL;
471 		psrc = (__be32 *)skb_put(skb, sizeof(__be32));
472 		*psrc = psf->sf_inaddr;
473 		scount++; stotal++;
474 		if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
475 		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
476 			psf->sf_crcount--;
477 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
478 				if (psf_prev)
479 					psf_prev->sf_next = psf->sf_next;
480 				else
481 					*psf_list = psf->sf_next;
482 				kfree(psf);
483 				continue;
484 			}
485 		}
486 		psf_prev = psf;
487 	}
488 
489 empty_source:
490 	if (!stotal) {
491 		if (type == IGMPV3_ALLOW_NEW_SOURCES ||
492 		    type == IGMPV3_BLOCK_OLD_SOURCES)
493 			return skb;
494 		if (pmc->crcount || isquery) {
495 			/* make sure we have room for group header */
496 			if (skb && AVAILABLE(skb)<sizeof(struct igmpv3_grec)) {
497 				igmpv3_sendpack(skb);
498 				skb = NULL; /* add_grhead will get a new one */
499 			}
500 			skb = add_grhead(skb, pmc, type, &pgr);
501 		}
502 	}
503 	if (pgr)
504 		pgr->grec_nsrcs = htons(scount);
505 
506 	if (isquery)
507 		pmc->gsquery = 0;	/* clear query state on report */
508 	return skb;
509 }
510 
511 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
512 {
513 	struct sk_buff *skb = NULL;
514 	int type;
515 
516 	if (!pmc) {
517 		rcu_read_lock();
518 		for_each_pmc_rcu(in_dev, pmc) {
519 			if (pmc->multiaddr == IGMP_ALL_HOSTS)
520 				continue;
521 			spin_lock_bh(&pmc->lock);
522 			if (pmc->sfcount[MCAST_EXCLUDE])
523 				type = IGMPV3_MODE_IS_EXCLUDE;
524 			else
525 				type = IGMPV3_MODE_IS_INCLUDE;
526 			skb = add_grec(skb, pmc, type, 0, 0);
527 			spin_unlock_bh(&pmc->lock);
528 		}
529 		rcu_read_unlock();
530 	} else {
531 		spin_lock_bh(&pmc->lock);
532 		if (pmc->sfcount[MCAST_EXCLUDE])
533 			type = IGMPV3_MODE_IS_EXCLUDE;
534 		else
535 			type = IGMPV3_MODE_IS_INCLUDE;
536 		skb = add_grec(skb, pmc, type, 0, 0);
537 		spin_unlock_bh(&pmc->lock);
538 	}
539 	if (!skb)
540 		return 0;
541 	return igmpv3_sendpack(skb);
542 }
543 
544 /*
545  * remove zero-count source records from a source filter list
546  */
547 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
548 {
549 	struct ip_sf_list *psf_prev, *psf_next, *psf;
550 
551 	psf_prev = NULL;
552 	for (psf=*ppsf; psf; psf = psf_next) {
553 		psf_next = psf->sf_next;
554 		if (psf->sf_crcount == 0) {
555 			if (psf_prev)
556 				psf_prev->sf_next = psf->sf_next;
557 			else
558 				*ppsf = psf->sf_next;
559 			kfree(psf);
560 		} else
561 			psf_prev = psf;
562 	}
563 }
564 
565 static void igmpv3_send_cr(struct in_device *in_dev)
566 {
567 	struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
568 	struct sk_buff *skb = NULL;
569 	int type, dtype;
570 
571 	rcu_read_lock();
572 	spin_lock_bh(&in_dev->mc_tomb_lock);
573 
574 	/* deleted MCA's */
575 	pmc_prev = NULL;
576 	for (pmc=in_dev->mc_tomb; pmc; pmc=pmc_next) {
577 		pmc_next = pmc->next;
578 		if (pmc->sfmode == MCAST_INCLUDE) {
579 			type = IGMPV3_BLOCK_OLD_SOURCES;
580 			dtype = IGMPV3_BLOCK_OLD_SOURCES;
581 			skb = add_grec(skb, pmc, type, 1, 0);
582 			skb = add_grec(skb, pmc, dtype, 1, 1);
583 		}
584 		if (pmc->crcount) {
585 			if (pmc->sfmode == MCAST_EXCLUDE) {
586 				type = IGMPV3_CHANGE_TO_INCLUDE;
587 				skb = add_grec(skb, pmc, type, 1, 0);
588 			}
589 			pmc->crcount--;
590 			if (pmc->crcount == 0) {
591 				igmpv3_clear_zeros(&pmc->tomb);
592 				igmpv3_clear_zeros(&pmc->sources);
593 			}
594 		}
595 		if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
596 			if (pmc_prev)
597 				pmc_prev->next = pmc_next;
598 			else
599 				in_dev->mc_tomb = pmc_next;
600 			in_dev_put(pmc->interface);
601 			kfree(pmc);
602 		} else
603 			pmc_prev = pmc;
604 	}
605 	spin_unlock_bh(&in_dev->mc_tomb_lock);
606 
607 	/* change recs */
608 	for_each_pmc_rcu(in_dev, pmc) {
609 		spin_lock_bh(&pmc->lock);
610 		if (pmc->sfcount[MCAST_EXCLUDE]) {
611 			type = IGMPV3_BLOCK_OLD_SOURCES;
612 			dtype = IGMPV3_ALLOW_NEW_SOURCES;
613 		} else {
614 			type = IGMPV3_ALLOW_NEW_SOURCES;
615 			dtype = IGMPV3_BLOCK_OLD_SOURCES;
616 		}
617 		skb = add_grec(skb, pmc, type, 0, 0);
618 		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
619 
620 		/* filter mode changes */
621 		if (pmc->crcount) {
622 			if (pmc->sfmode == MCAST_EXCLUDE)
623 				type = IGMPV3_CHANGE_TO_EXCLUDE;
624 			else
625 				type = IGMPV3_CHANGE_TO_INCLUDE;
626 			skb = add_grec(skb, pmc, type, 0, 0);
627 			pmc->crcount--;
628 		}
629 		spin_unlock_bh(&pmc->lock);
630 	}
631 	rcu_read_unlock();
632 
633 	if (!skb)
634 		return;
635 	(void) igmpv3_sendpack(skb);
636 }
637 
638 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
639 	int type)
640 {
641 	struct sk_buff *skb;
642 	struct iphdr *iph;
643 	struct igmphdr *ih;
644 	struct rtable *rt;
645 	struct net_device *dev = in_dev->dev;
646 	struct net *net = dev_net(dev);
647 	__be32	group = pmc ? pmc->multiaddr : 0;
648 	struct flowi4 fl4;
649 	__be32	dst;
650 
651 	if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
652 		return igmpv3_send_report(in_dev, pmc);
653 	else if (type == IGMP_HOST_LEAVE_MESSAGE)
654 		dst = IGMP_ALL_ROUTER;
655 	else
656 		dst = group;
657 
658 	rt = ip_route_output_ports(net, &fl4, NULL, dst, 0,
659 				   0, 0,
660 				   IPPROTO_IGMP, 0, dev->ifindex);
661 	if (IS_ERR(rt))
662 		return -1;
663 
664 	skb = alloc_skb(IGMP_SIZE+LL_ALLOCATED_SPACE(dev), GFP_ATOMIC);
665 	if (skb == NULL) {
666 		ip_rt_put(rt);
667 		return -1;
668 	}
669 
670 	skb_dst_set(skb, &rt->dst);
671 
672 	skb_reserve(skb, LL_RESERVED_SPACE(dev));
673 
674 	skb_reset_network_header(skb);
675 	iph = ip_hdr(skb);
676 	skb_put(skb, sizeof(struct iphdr) + 4);
677 
678 	iph->version  = 4;
679 	iph->ihl      = (sizeof(struct iphdr)+4)>>2;
680 	iph->tos      = 0xc0;
681 	iph->frag_off = htons(IP_DF);
682 	iph->ttl      = 1;
683 	iph->daddr    = dst;
684 	iph->saddr    = fl4.saddr;
685 	iph->protocol = IPPROTO_IGMP;
686 	ip_select_ident(iph, &rt->dst, NULL);
687 	((u8*)&iph[1])[0] = IPOPT_RA;
688 	((u8*)&iph[1])[1] = 4;
689 	((u8*)&iph[1])[2] = 0;
690 	((u8*)&iph[1])[3] = 0;
691 
692 	ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
693 	ih->type = type;
694 	ih->code = 0;
695 	ih->csum = 0;
696 	ih->group = group;
697 	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
698 
699 	return ip_local_out(skb);
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 (psf->sf_count[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 	rcu_read_lock();
824 	for_each_pmc_rcu(in_dev, im) {
825 		if (im->multiaddr == group) {
826 			igmp_stop_timer(im);
827 			break;
828 		}
829 	}
830 	rcu_read_unlock();
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 if (IGMP_V1_SEEN(in_dev)) {
867 		/* This is a v3 query with v1 queriers present */
868 		max_delay = IGMP_Query_Response_Interval;
869 		group = 0;
870 	} else if (IGMP_V2_SEEN(in_dev)) {
871 		/* this is a v3 query with v2 queriers present;
872 		 * Interpretation of the max_delay code is problematic here.
873 		 * A real v2 host would use ih_code directly, while v3 has a
874 		 * different encoding. We use the v3 encoding as more likely
875 		 * to be intended in a v3 query.
876 		 */
877 		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
878 	} else { /* v3 */
879 		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
880 			return;
881 
882 		ih3 = igmpv3_query_hdr(skb);
883 		if (ih3->nsrcs) {
884 			if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
885 					   + ntohs(ih3->nsrcs)*sizeof(__be32)))
886 				return;
887 			ih3 = igmpv3_query_hdr(skb);
888 		}
889 
890 		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
891 		if (!max_delay)
892 			max_delay = 1;	/* can't mod w/ 0 */
893 		in_dev->mr_maxdelay = max_delay;
894 		if (ih3->qrv)
895 			in_dev->mr_qrv = ih3->qrv;
896 		if (!group) { /* general query */
897 			if (ih3->nsrcs)
898 				return;	/* no sources allowed */
899 			igmp_gq_start_timer(in_dev);
900 			return;
901 		}
902 		/* mark sources to include, if group & source-specific */
903 		mark = ih3->nsrcs != 0;
904 	}
905 
906 	/*
907 	 * - Start the timers in all of our membership records
908 	 *   that the query applies to for the interface on
909 	 *   which the query arrived excl. those that belong
910 	 *   to a "local" group (224.0.0.X)
911 	 * - For timers already running check if they need to
912 	 *   be reset.
913 	 * - Use the igmp->igmp_code field as the maximum
914 	 *   delay possible
915 	 */
916 	rcu_read_lock();
917 	for_each_pmc_rcu(in_dev, im) {
918 		int changed;
919 
920 		if (group && group != im->multiaddr)
921 			continue;
922 		if (im->multiaddr == IGMP_ALL_HOSTS)
923 			continue;
924 		spin_lock_bh(&im->lock);
925 		if (im->tm_running)
926 			im->gsquery = im->gsquery && mark;
927 		else
928 			im->gsquery = mark;
929 		changed = !im->gsquery ||
930 			igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
931 		spin_unlock_bh(&im->lock);
932 		if (changed)
933 			igmp_mod_timer(im, max_delay);
934 	}
935 	rcu_read_unlock();
936 }
937 
938 /* called in rcu_read_lock() section */
939 int igmp_rcv(struct sk_buff *skb)
940 {
941 	/* This basically follows the spec line by line -- see RFC1112 */
942 	struct igmphdr *ih;
943 	struct in_device *in_dev = __in_dev_get_rcu(skb->dev);
944 	int len = skb->len;
945 
946 	if (in_dev == NULL)
947 		goto drop;
948 
949 	if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
950 		goto drop;
951 
952 	switch (skb->ip_summed) {
953 	case CHECKSUM_COMPLETE:
954 		if (!csum_fold(skb->csum))
955 			break;
956 		/* fall through */
957 	case CHECKSUM_NONE:
958 		skb->csum = 0;
959 		if (__skb_checksum_complete(skb))
960 			goto drop;
961 	}
962 
963 	ih = igmp_hdr(skb);
964 	switch (ih->type) {
965 	case IGMP_HOST_MEMBERSHIP_QUERY:
966 		igmp_heard_query(in_dev, skb, len);
967 		break;
968 	case IGMP_HOST_MEMBERSHIP_REPORT:
969 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
970 		/* Is it our report looped back? */
971 		if (rt_is_output_route(skb_rtable(skb)))
972 			break;
973 		/* don't rely on MC router hearing unicast reports */
974 		if (skb->pkt_type == PACKET_MULTICAST ||
975 		    skb->pkt_type == PACKET_BROADCAST)
976 			igmp_heard_report(in_dev, ih->group);
977 		break;
978 	case IGMP_PIM:
979 #ifdef CONFIG_IP_PIMSM_V1
980 		return pim_rcv_v1(skb);
981 #endif
982 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
983 	case IGMP_DVMRP:
984 	case IGMP_TRACE:
985 	case IGMP_HOST_LEAVE_MESSAGE:
986 	case IGMP_MTRACE:
987 	case IGMP_MTRACE_RESP:
988 		break;
989 	default:
990 		break;
991 	}
992 
993 drop:
994 	kfree_skb(skb);
995 	return 0;
996 }
997 
998 #endif
999 
1000 
1001 /*
1002  *	Add a filter to a device
1003  */
1004 
1005 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1006 {
1007 	char buf[MAX_ADDR_LEN];
1008 	struct net_device *dev = in_dev->dev;
1009 
1010 	/* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1011 	   We will get multicast token leakage, when IFF_MULTICAST
1012 	   is changed. This check should be done in dev->set_multicast_list
1013 	   routine. Something sort of:
1014 	   if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1015 	   --ANK
1016 	   */
1017 	if (arp_mc_map(addr, buf, dev, 0) == 0)
1018 		dev_mc_add(dev, buf);
1019 }
1020 
1021 /*
1022  *	Remove a filter from a device
1023  */
1024 
1025 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1026 {
1027 	char buf[MAX_ADDR_LEN];
1028 	struct net_device *dev = in_dev->dev;
1029 
1030 	if (arp_mc_map(addr, buf, dev, 0) == 0)
1031 		dev_mc_del(dev, buf);
1032 }
1033 
1034 #ifdef CONFIG_IP_MULTICAST
1035 /*
1036  * deleted ip_mc_list manipulation
1037  */
1038 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1039 {
1040 	struct ip_mc_list *pmc;
1041 
1042 	/* this is an "ip_mc_list" for convenience; only the fields below
1043 	 * are actually used. In particular, the refcnt and users are not
1044 	 * used for management of the delete list. Using the same structure
1045 	 * for deleted items allows change reports to use common code with
1046 	 * non-deleted or query-response MCA's.
1047 	 */
1048 	pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
1049 	if (!pmc)
1050 		return;
1051 	spin_lock_bh(&im->lock);
1052 	pmc->interface = im->interface;
1053 	in_dev_hold(in_dev);
1054 	pmc->multiaddr = im->multiaddr;
1055 	pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1056 		IGMP_Unsolicited_Report_Count;
1057 	pmc->sfmode = im->sfmode;
1058 	if (pmc->sfmode == MCAST_INCLUDE) {
1059 		struct ip_sf_list *psf;
1060 
1061 		pmc->tomb = im->tomb;
1062 		pmc->sources = im->sources;
1063 		im->tomb = im->sources = NULL;
1064 		for (psf=pmc->sources; psf; psf=psf->sf_next)
1065 			psf->sf_crcount = pmc->crcount;
1066 	}
1067 	spin_unlock_bh(&im->lock);
1068 
1069 	spin_lock_bh(&in_dev->mc_tomb_lock);
1070 	pmc->next = in_dev->mc_tomb;
1071 	in_dev->mc_tomb = pmc;
1072 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1073 }
1074 
1075 static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr)
1076 {
1077 	struct ip_mc_list *pmc, *pmc_prev;
1078 	struct ip_sf_list *psf, *psf_next;
1079 
1080 	spin_lock_bh(&in_dev->mc_tomb_lock);
1081 	pmc_prev = NULL;
1082 	for (pmc=in_dev->mc_tomb; pmc; pmc=pmc->next) {
1083 		if (pmc->multiaddr == multiaddr)
1084 			break;
1085 		pmc_prev = pmc;
1086 	}
1087 	if (pmc) {
1088 		if (pmc_prev)
1089 			pmc_prev->next = pmc->next;
1090 		else
1091 			in_dev->mc_tomb = pmc->next;
1092 	}
1093 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1094 	if (pmc) {
1095 		for (psf=pmc->tomb; psf; psf=psf_next) {
1096 			psf_next = psf->sf_next;
1097 			kfree(psf);
1098 		}
1099 		in_dev_put(pmc->interface);
1100 		kfree(pmc);
1101 	}
1102 }
1103 
1104 static void igmpv3_clear_delrec(struct in_device *in_dev)
1105 {
1106 	struct ip_mc_list *pmc, *nextpmc;
1107 
1108 	spin_lock_bh(&in_dev->mc_tomb_lock);
1109 	pmc = in_dev->mc_tomb;
1110 	in_dev->mc_tomb = NULL;
1111 	spin_unlock_bh(&in_dev->mc_tomb_lock);
1112 
1113 	for (; pmc; pmc = nextpmc) {
1114 		nextpmc = pmc->next;
1115 		ip_mc_clear_src(pmc);
1116 		in_dev_put(pmc->interface);
1117 		kfree(pmc);
1118 	}
1119 	/* clear dead sources, too */
1120 	rcu_read_lock();
1121 	for_each_pmc_rcu(in_dev, pmc) {
1122 		struct ip_sf_list *psf, *psf_next;
1123 
1124 		spin_lock_bh(&pmc->lock);
1125 		psf = pmc->tomb;
1126 		pmc->tomb = NULL;
1127 		spin_unlock_bh(&pmc->lock);
1128 		for (; psf; psf=psf_next) {
1129 			psf_next = psf->sf_next;
1130 			kfree(psf);
1131 		}
1132 	}
1133 	rcu_read_unlock();
1134 }
1135 #endif
1136 
1137 static void igmp_group_dropped(struct ip_mc_list *im)
1138 {
1139 	struct in_device *in_dev = im->interface;
1140 #ifdef CONFIG_IP_MULTICAST
1141 	int reporter;
1142 #endif
1143 
1144 	if (im->loaded) {
1145 		im->loaded = 0;
1146 		ip_mc_filter_del(in_dev, im->multiaddr);
1147 	}
1148 
1149 #ifdef CONFIG_IP_MULTICAST
1150 	if (im->multiaddr == IGMP_ALL_HOSTS)
1151 		return;
1152 
1153 	reporter = im->reporter;
1154 	igmp_stop_timer(im);
1155 
1156 	if (!in_dev->dead) {
1157 		if (IGMP_V1_SEEN(in_dev))
1158 			return;
1159 		if (IGMP_V2_SEEN(in_dev)) {
1160 			if (reporter)
1161 				igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1162 			return;
1163 		}
1164 		/* IGMPv3 */
1165 		igmpv3_add_delrec(in_dev, im);
1166 
1167 		igmp_ifc_event(in_dev);
1168 	}
1169 #endif
1170 }
1171 
1172 static void igmp_group_added(struct ip_mc_list *im)
1173 {
1174 	struct in_device *in_dev = im->interface;
1175 
1176 	if (im->loaded == 0) {
1177 		im->loaded = 1;
1178 		ip_mc_filter_add(in_dev, im->multiaddr);
1179 	}
1180 
1181 #ifdef CONFIG_IP_MULTICAST
1182 	if (im->multiaddr == IGMP_ALL_HOSTS)
1183 		return;
1184 
1185 	if (in_dev->dead)
1186 		return;
1187 	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1188 		spin_lock_bh(&im->lock);
1189 		igmp_start_timer(im, IGMP_Initial_Report_Delay);
1190 		spin_unlock_bh(&im->lock);
1191 		return;
1192 	}
1193 	/* else, v3 */
1194 
1195 	im->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1196 		IGMP_Unsolicited_Report_Count;
1197 	igmp_ifc_event(in_dev);
1198 #endif
1199 }
1200 
1201 
1202 /*
1203  *	Multicast list managers
1204  */
1205 
1206 
1207 /*
1208  *	A socket has joined a multicast group on device dev.
1209  */
1210 
1211 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1212 {
1213 	struct ip_mc_list *im;
1214 
1215 	ASSERT_RTNL();
1216 
1217 	for_each_pmc_rtnl(in_dev, im) {
1218 		if (im->multiaddr == addr) {
1219 			im->users++;
1220 			ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1221 			goto out;
1222 		}
1223 	}
1224 
1225 	im = kzalloc(sizeof(*im), GFP_KERNEL);
1226 	if (!im)
1227 		goto out;
1228 
1229 	im->users = 1;
1230 	im->interface = in_dev;
1231 	in_dev_hold(in_dev);
1232 	im->multiaddr = addr;
1233 	/* initial mode is (EX, empty) */
1234 	im->sfmode = MCAST_EXCLUDE;
1235 	im->sfcount[MCAST_EXCLUDE] = 1;
1236 	atomic_set(&im->refcnt, 1);
1237 	spin_lock_init(&im->lock);
1238 #ifdef CONFIG_IP_MULTICAST
1239 	setup_timer(&im->timer, &igmp_timer_expire, (unsigned long)im);
1240 	im->unsolicit_count = IGMP_Unsolicited_Report_Count;
1241 #endif
1242 
1243 	im->next_rcu = in_dev->mc_list;
1244 	in_dev->mc_count++;
1245 	rcu_assign_pointer(in_dev->mc_list, im);
1246 
1247 #ifdef CONFIG_IP_MULTICAST
1248 	igmpv3_del_delrec(in_dev, im->multiaddr);
1249 #endif
1250 	igmp_group_added(im);
1251 	if (!in_dev->dead)
1252 		ip_rt_multicast_event(in_dev);
1253 out:
1254 	return;
1255 }
1256 EXPORT_SYMBOL(ip_mc_inc_group);
1257 
1258 /*
1259  *	Resend IGMP JOIN report; used for bonding.
1260  *	Called with rcu_read_lock()
1261  */
1262 void ip_mc_rejoin_groups(struct in_device *in_dev)
1263 {
1264 #ifdef CONFIG_IP_MULTICAST
1265 	struct ip_mc_list *im;
1266 	int type;
1267 
1268 	for_each_pmc_rcu(in_dev, im) {
1269 		if (im->multiaddr == IGMP_ALL_HOSTS)
1270 			continue;
1271 
1272 		/* a failover is happening and switches
1273 		 * must be notified immediately
1274 		 */
1275 		if (IGMP_V1_SEEN(in_dev))
1276 			type = IGMP_HOST_MEMBERSHIP_REPORT;
1277 		else if (IGMP_V2_SEEN(in_dev))
1278 			type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1279 		else
1280 			type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1281 		igmp_send_report(in_dev, im, type);
1282 	}
1283 #endif
1284 }
1285 EXPORT_SYMBOL(ip_mc_rejoin_groups);
1286 
1287 /*
1288  *	A socket has left a multicast group on device dev
1289  */
1290 
1291 void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
1292 {
1293 	struct ip_mc_list *i;
1294 	struct ip_mc_list __rcu **ip;
1295 
1296 	ASSERT_RTNL();
1297 
1298 	for (ip = &in_dev->mc_list;
1299 	     (i = rtnl_dereference(*ip)) != NULL;
1300 	     ip = &i->next_rcu) {
1301 		if (i->multiaddr == addr) {
1302 			if (--i->users == 0) {
1303 				*ip = i->next_rcu;
1304 				in_dev->mc_count--;
1305 				igmp_group_dropped(i);
1306 				ip_mc_clear_src(i);
1307 
1308 				if (!in_dev->dead)
1309 					ip_rt_multicast_event(in_dev);
1310 
1311 				ip_ma_put(i);
1312 				return;
1313 			}
1314 			break;
1315 		}
1316 	}
1317 }
1318 EXPORT_SYMBOL(ip_mc_dec_group);
1319 
1320 /* Device changing type */
1321 
1322 void ip_mc_unmap(struct in_device *in_dev)
1323 {
1324 	struct ip_mc_list *pmc;
1325 
1326 	ASSERT_RTNL();
1327 
1328 	for_each_pmc_rtnl(in_dev, pmc)
1329 		igmp_group_dropped(pmc);
1330 }
1331 
1332 void ip_mc_remap(struct in_device *in_dev)
1333 {
1334 	struct ip_mc_list *pmc;
1335 
1336 	ASSERT_RTNL();
1337 
1338 	for_each_pmc_rtnl(in_dev, pmc)
1339 		igmp_group_added(pmc);
1340 }
1341 
1342 /* Device going down */
1343 
1344 void ip_mc_down(struct in_device *in_dev)
1345 {
1346 	struct ip_mc_list *pmc;
1347 
1348 	ASSERT_RTNL();
1349 
1350 	for_each_pmc_rtnl(in_dev, pmc)
1351 		igmp_group_dropped(pmc);
1352 
1353 #ifdef CONFIG_IP_MULTICAST
1354 	in_dev->mr_ifc_count = 0;
1355 	if (del_timer(&in_dev->mr_ifc_timer))
1356 		__in_dev_put(in_dev);
1357 	in_dev->mr_gq_running = 0;
1358 	if (del_timer(&in_dev->mr_gq_timer))
1359 		__in_dev_put(in_dev);
1360 	igmpv3_clear_delrec(in_dev);
1361 #endif
1362 
1363 	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1364 }
1365 
1366 void ip_mc_init_dev(struct in_device *in_dev)
1367 {
1368 	ASSERT_RTNL();
1369 
1370 	in_dev->mc_tomb = NULL;
1371 #ifdef CONFIG_IP_MULTICAST
1372 	in_dev->mr_gq_running = 0;
1373 	setup_timer(&in_dev->mr_gq_timer, igmp_gq_timer_expire,
1374 			(unsigned long)in_dev);
1375 	in_dev->mr_ifc_count = 0;
1376 	in_dev->mc_count     = 0;
1377 	setup_timer(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire,
1378 			(unsigned long)in_dev);
1379 	in_dev->mr_qrv = IGMP_Unsolicited_Report_Count;
1380 #endif
1381 
1382 	spin_lock_init(&in_dev->mc_tomb_lock);
1383 }
1384 
1385 /* Device going up */
1386 
1387 void ip_mc_up(struct in_device *in_dev)
1388 {
1389 	struct ip_mc_list *pmc;
1390 
1391 	ASSERT_RTNL();
1392 
1393 	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1394 
1395 	for_each_pmc_rtnl(in_dev, pmc)
1396 		igmp_group_added(pmc);
1397 }
1398 
1399 /*
1400  *	Device is about to be destroyed: clean up.
1401  */
1402 
1403 void ip_mc_destroy_dev(struct in_device *in_dev)
1404 {
1405 	struct ip_mc_list *i;
1406 
1407 	ASSERT_RTNL();
1408 
1409 	/* Deactivate timers */
1410 	ip_mc_down(in_dev);
1411 
1412 	while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1413 		in_dev->mc_list = i->next_rcu;
1414 		in_dev->mc_count--;
1415 
1416 		/* We've dropped the groups in ip_mc_down already */
1417 		ip_mc_clear_src(i);
1418 		ip_ma_put(i);
1419 	}
1420 }
1421 
1422 /* RTNL is locked */
1423 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1424 {
1425 	struct net_device *dev = NULL;
1426 	struct in_device *idev = NULL;
1427 
1428 	if (imr->imr_ifindex) {
1429 		idev = inetdev_by_index(net, imr->imr_ifindex);
1430 		return idev;
1431 	}
1432 	if (imr->imr_address.s_addr) {
1433 		dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1434 		if (!dev)
1435 			return NULL;
1436 	}
1437 
1438 	if (!dev) {
1439 		struct rtable *rt = ip_route_output(net,
1440 						    imr->imr_multiaddr.s_addr,
1441 						    0, 0, 0);
1442 		if (!IS_ERR(rt)) {
1443 			dev = rt->dst.dev;
1444 			ip_rt_put(rt);
1445 		}
1446 	}
1447 	if (dev) {
1448 		imr->imr_ifindex = dev->ifindex;
1449 		idev = __in_dev_get_rtnl(dev);
1450 	}
1451 	return idev;
1452 }
1453 
1454 /*
1455  *	Join a socket to a group
1456  */
1457 int sysctl_igmp_max_memberships __read_mostly = IP_MAX_MEMBERSHIPS;
1458 int sysctl_igmp_max_msf __read_mostly = IP_MAX_MSF;
1459 
1460 
1461 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1462 	__be32 *psfsrc)
1463 {
1464 	struct ip_sf_list *psf, *psf_prev;
1465 	int rv = 0;
1466 
1467 	psf_prev = NULL;
1468 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1469 		if (psf->sf_inaddr == *psfsrc)
1470 			break;
1471 		psf_prev = psf;
1472 	}
1473 	if (!psf || psf->sf_count[sfmode] == 0) {
1474 		/* source filter not found, or count wrong =>  bug */
1475 		return -ESRCH;
1476 	}
1477 	psf->sf_count[sfmode]--;
1478 	if (psf->sf_count[sfmode] == 0) {
1479 		ip_rt_multicast_event(pmc->interface);
1480 	}
1481 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1482 #ifdef CONFIG_IP_MULTICAST
1483 		struct in_device *in_dev = pmc->interface;
1484 #endif
1485 
1486 		/* no more filters for this source */
1487 		if (psf_prev)
1488 			psf_prev->sf_next = psf->sf_next;
1489 		else
1490 			pmc->sources = psf->sf_next;
1491 #ifdef CONFIG_IP_MULTICAST
1492 		if (psf->sf_oldin &&
1493 		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1494 			psf->sf_crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1495 				IGMP_Unsolicited_Report_Count;
1496 			psf->sf_next = pmc->tomb;
1497 			pmc->tomb = psf;
1498 			rv = 1;
1499 		} else
1500 #endif
1501 			kfree(psf);
1502 	}
1503 	return rv;
1504 }
1505 
1506 #ifndef CONFIG_IP_MULTICAST
1507 #define igmp_ifc_event(x)	do { } while (0)
1508 #endif
1509 
1510 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1511 			 int sfcount, __be32 *psfsrc, int delta)
1512 {
1513 	struct ip_mc_list *pmc;
1514 	int	changerec = 0;
1515 	int	i, err;
1516 
1517 	if (!in_dev)
1518 		return -ENODEV;
1519 	rcu_read_lock();
1520 	for_each_pmc_rcu(in_dev, pmc) {
1521 		if (*pmca == pmc->multiaddr)
1522 			break;
1523 	}
1524 	if (!pmc) {
1525 		/* MCA not found?? bug */
1526 		rcu_read_unlock();
1527 		return -ESRCH;
1528 	}
1529 	spin_lock_bh(&pmc->lock);
1530 	rcu_read_unlock();
1531 #ifdef CONFIG_IP_MULTICAST
1532 	sf_markstate(pmc);
1533 #endif
1534 	if (!delta) {
1535 		err = -EINVAL;
1536 		if (!pmc->sfcount[sfmode])
1537 			goto out_unlock;
1538 		pmc->sfcount[sfmode]--;
1539 	}
1540 	err = 0;
1541 	for (i=0; i<sfcount; i++) {
1542 		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1543 
1544 		changerec |= rv > 0;
1545 		if (!err && rv < 0)
1546 			err = rv;
1547 	}
1548 	if (pmc->sfmode == MCAST_EXCLUDE &&
1549 	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1550 	    pmc->sfcount[MCAST_INCLUDE]) {
1551 #ifdef CONFIG_IP_MULTICAST
1552 		struct ip_sf_list *psf;
1553 #endif
1554 
1555 		/* filter mode change */
1556 		pmc->sfmode = MCAST_INCLUDE;
1557 #ifdef CONFIG_IP_MULTICAST
1558 		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1559 			IGMP_Unsolicited_Report_Count;
1560 		in_dev->mr_ifc_count = pmc->crcount;
1561 		for (psf=pmc->sources; psf; psf = psf->sf_next)
1562 			psf->sf_crcount = 0;
1563 		igmp_ifc_event(pmc->interface);
1564 	} else if (sf_setstate(pmc) || changerec) {
1565 		igmp_ifc_event(pmc->interface);
1566 #endif
1567 	}
1568 out_unlock:
1569 	spin_unlock_bh(&pmc->lock);
1570 	return err;
1571 }
1572 
1573 /*
1574  * Add multicast single-source filter to the interface list
1575  */
1576 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1577 	__be32 *psfsrc, int delta)
1578 {
1579 	struct ip_sf_list *psf, *psf_prev;
1580 
1581 	psf_prev = NULL;
1582 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1583 		if (psf->sf_inaddr == *psfsrc)
1584 			break;
1585 		psf_prev = psf;
1586 	}
1587 	if (!psf) {
1588 		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1589 		if (!psf)
1590 			return -ENOBUFS;
1591 		psf->sf_inaddr = *psfsrc;
1592 		if (psf_prev) {
1593 			psf_prev->sf_next = psf;
1594 		} else
1595 			pmc->sources = psf;
1596 	}
1597 	psf->sf_count[sfmode]++;
1598 	if (psf->sf_count[sfmode] == 1) {
1599 		ip_rt_multicast_event(pmc->interface);
1600 	}
1601 	return 0;
1602 }
1603 
1604 #ifdef CONFIG_IP_MULTICAST
1605 static void sf_markstate(struct ip_mc_list *pmc)
1606 {
1607 	struct ip_sf_list *psf;
1608 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1609 
1610 	for (psf=pmc->sources; psf; psf=psf->sf_next)
1611 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1612 			psf->sf_oldin = mca_xcount ==
1613 				psf->sf_count[MCAST_EXCLUDE] &&
1614 				!psf->sf_count[MCAST_INCLUDE];
1615 		} else
1616 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1617 }
1618 
1619 static int sf_setstate(struct ip_mc_list *pmc)
1620 {
1621 	struct ip_sf_list *psf, *dpsf;
1622 	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1623 	int qrv = pmc->interface->mr_qrv;
1624 	int new_in, rv;
1625 
1626 	rv = 0;
1627 	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1628 		if (pmc->sfcount[MCAST_EXCLUDE]) {
1629 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1630 				!psf->sf_count[MCAST_INCLUDE];
1631 		} else
1632 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1633 		if (new_in) {
1634 			if (!psf->sf_oldin) {
1635 				struct ip_sf_list *prev = NULL;
1636 
1637 				for (dpsf=pmc->tomb; dpsf; dpsf=dpsf->sf_next) {
1638 					if (dpsf->sf_inaddr == psf->sf_inaddr)
1639 						break;
1640 					prev = dpsf;
1641 				}
1642 				if (dpsf) {
1643 					if (prev)
1644 						prev->sf_next = dpsf->sf_next;
1645 					else
1646 						pmc->tomb = dpsf->sf_next;
1647 					kfree(dpsf);
1648 				}
1649 				psf->sf_crcount = qrv;
1650 				rv++;
1651 			}
1652 		} else if (psf->sf_oldin) {
1653 
1654 			psf->sf_crcount = 0;
1655 			/*
1656 			 * add or update "delete" records if an active filter
1657 			 * is now inactive
1658 			 */
1659 			for (dpsf=pmc->tomb; dpsf; dpsf=dpsf->sf_next)
1660 				if (dpsf->sf_inaddr == psf->sf_inaddr)
1661 					break;
1662 			if (!dpsf) {
1663 				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
1664 				if (!dpsf)
1665 					continue;
1666 				*dpsf = *psf;
1667 				/* pmc->lock held by callers */
1668 				dpsf->sf_next = pmc->tomb;
1669 				pmc->tomb = dpsf;
1670 			}
1671 			dpsf->sf_crcount = qrv;
1672 			rv++;
1673 		}
1674 	}
1675 	return rv;
1676 }
1677 #endif
1678 
1679 /*
1680  * Add multicast source filter list to the interface list
1681  */
1682 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1683 			 int sfcount, __be32 *psfsrc, int delta)
1684 {
1685 	struct ip_mc_list *pmc;
1686 	int	isexclude;
1687 	int	i, err;
1688 
1689 	if (!in_dev)
1690 		return -ENODEV;
1691 	rcu_read_lock();
1692 	for_each_pmc_rcu(in_dev, pmc) {
1693 		if (*pmca == pmc->multiaddr)
1694 			break;
1695 	}
1696 	if (!pmc) {
1697 		/* MCA not found?? bug */
1698 		rcu_read_unlock();
1699 		return -ESRCH;
1700 	}
1701 	spin_lock_bh(&pmc->lock);
1702 	rcu_read_unlock();
1703 
1704 #ifdef CONFIG_IP_MULTICAST
1705 	sf_markstate(pmc);
1706 #endif
1707 	isexclude = pmc->sfmode == MCAST_EXCLUDE;
1708 	if (!delta)
1709 		pmc->sfcount[sfmode]++;
1710 	err = 0;
1711 	for (i=0; i<sfcount; i++) {
1712 		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i], delta);
1713 		if (err)
1714 			break;
1715 	}
1716 	if (err) {
1717 		int j;
1718 
1719 		pmc->sfcount[sfmode]--;
1720 		for (j=0; j<i; j++)
1721 			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
1722 	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
1723 #ifdef CONFIG_IP_MULTICAST
1724 		struct ip_sf_list *psf;
1725 		in_dev = pmc->interface;
1726 #endif
1727 
1728 		/* filter mode change */
1729 		if (pmc->sfcount[MCAST_EXCLUDE])
1730 			pmc->sfmode = MCAST_EXCLUDE;
1731 		else if (pmc->sfcount[MCAST_INCLUDE])
1732 			pmc->sfmode = MCAST_INCLUDE;
1733 #ifdef CONFIG_IP_MULTICAST
1734 		/* else no filters; keep old mode for reports */
1735 
1736 		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1737 			IGMP_Unsolicited_Report_Count;
1738 		in_dev->mr_ifc_count = pmc->crcount;
1739 		for (psf=pmc->sources; psf; psf = psf->sf_next)
1740 			psf->sf_crcount = 0;
1741 		igmp_ifc_event(in_dev);
1742 	} else if (sf_setstate(pmc)) {
1743 		igmp_ifc_event(in_dev);
1744 #endif
1745 	}
1746 	spin_unlock_bh(&pmc->lock);
1747 	return err;
1748 }
1749 
1750 static void ip_mc_clear_src(struct ip_mc_list *pmc)
1751 {
1752 	struct ip_sf_list *psf, *nextpsf;
1753 
1754 	for (psf=pmc->tomb; psf; psf=nextpsf) {
1755 		nextpsf = psf->sf_next;
1756 		kfree(psf);
1757 	}
1758 	pmc->tomb = NULL;
1759 	for (psf=pmc->sources; psf; psf=nextpsf) {
1760 		nextpsf = psf->sf_next;
1761 		kfree(psf);
1762 	}
1763 	pmc->sources = NULL;
1764 	pmc->sfmode = MCAST_EXCLUDE;
1765 	pmc->sfcount[MCAST_INCLUDE] = 0;
1766 	pmc->sfcount[MCAST_EXCLUDE] = 1;
1767 }
1768 
1769 
1770 /*
1771  * Join a multicast group
1772  */
1773 int ip_mc_join_group(struct sock *sk , struct ip_mreqn *imr)
1774 {
1775 	int err;
1776 	__be32 addr = imr->imr_multiaddr.s_addr;
1777 	struct ip_mc_socklist *iml = NULL, *i;
1778 	struct in_device *in_dev;
1779 	struct inet_sock *inet = inet_sk(sk);
1780 	struct net *net = sock_net(sk);
1781 	int ifindex;
1782 	int count = 0;
1783 
1784 	if (!ipv4_is_multicast(addr))
1785 		return -EINVAL;
1786 
1787 	rtnl_lock();
1788 
1789 	in_dev = ip_mc_find_dev(net, imr);
1790 
1791 	if (!in_dev) {
1792 		iml = NULL;
1793 		err = -ENODEV;
1794 		goto done;
1795 	}
1796 
1797 	err = -EADDRINUSE;
1798 	ifindex = imr->imr_ifindex;
1799 	for_each_pmc_rtnl(inet, i) {
1800 		if (i->multi.imr_multiaddr.s_addr == addr &&
1801 		    i->multi.imr_ifindex == ifindex)
1802 			goto done;
1803 		count++;
1804 	}
1805 	err = -ENOBUFS;
1806 	if (count >= sysctl_igmp_max_memberships)
1807 		goto done;
1808 	iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
1809 	if (iml == NULL)
1810 		goto done;
1811 
1812 	memcpy(&iml->multi, imr, sizeof(*imr));
1813 	iml->next_rcu = inet->mc_list;
1814 	iml->sflist = NULL;
1815 	iml->sfmode = MCAST_EXCLUDE;
1816 	rcu_assign_pointer(inet->mc_list, iml);
1817 	ip_mc_inc_group(in_dev, addr);
1818 	err = 0;
1819 done:
1820 	rtnl_unlock();
1821 	return err;
1822 }
1823 EXPORT_SYMBOL(ip_mc_join_group);
1824 
1825 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
1826 			   struct in_device *in_dev)
1827 {
1828 	struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
1829 	int err;
1830 
1831 	if (psf == NULL) {
1832 		/* any-source empty exclude case */
1833 		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1834 			iml->sfmode, 0, NULL, 0);
1835 	}
1836 	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1837 			iml->sfmode, psf->sl_count, psf->sl_addr, 0);
1838 	rcu_assign_pointer(iml->sflist, NULL);
1839 	/* decrease mem now to avoid the memleak warning */
1840 	atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc);
1841 	kfree_rcu(psf, rcu);
1842 	return err;
1843 }
1844 
1845 /*
1846  *	Ask a socket to leave a group.
1847  */
1848 
1849 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
1850 {
1851 	struct inet_sock *inet = inet_sk(sk);
1852 	struct ip_mc_socklist *iml;
1853 	struct ip_mc_socklist __rcu **imlp;
1854 	struct in_device *in_dev;
1855 	struct net *net = sock_net(sk);
1856 	__be32 group = imr->imr_multiaddr.s_addr;
1857 	u32 ifindex;
1858 	int ret = -EADDRNOTAVAIL;
1859 
1860 	rtnl_lock();
1861 	in_dev = ip_mc_find_dev(net, imr);
1862 	ifindex = imr->imr_ifindex;
1863 	for (imlp = &inet->mc_list;
1864 	     (iml = rtnl_dereference(*imlp)) != NULL;
1865 	     imlp = &iml->next_rcu) {
1866 		if (iml->multi.imr_multiaddr.s_addr != group)
1867 			continue;
1868 		if (ifindex) {
1869 			if (iml->multi.imr_ifindex != ifindex)
1870 				continue;
1871 		} else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
1872 				iml->multi.imr_address.s_addr)
1873 			continue;
1874 
1875 		(void) ip_mc_leave_src(sk, iml, in_dev);
1876 
1877 		*imlp = iml->next_rcu;
1878 
1879 		if (in_dev)
1880 			ip_mc_dec_group(in_dev, group);
1881 		rtnl_unlock();
1882 		/* decrease mem now to avoid the memleak warning */
1883 		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
1884 		kfree_rcu(iml, rcu);
1885 		return 0;
1886 	}
1887 	if (!in_dev)
1888 		ret = -ENODEV;
1889 	rtnl_unlock();
1890 	return ret;
1891 }
1892 
1893 int ip_mc_source(int add, int omode, struct sock *sk, struct
1894 	ip_mreq_source *mreqs, int ifindex)
1895 {
1896 	int err;
1897 	struct ip_mreqn imr;
1898 	__be32 addr = mreqs->imr_multiaddr;
1899 	struct ip_mc_socklist *pmc;
1900 	struct in_device *in_dev = NULL;
1901 	struct inet_sock *inet = inet_sk(sk);
1902 	struct ip_sf_socklist *psl;
1903 	struct net *net = sock_net(sk);
1904 	int leavegroup = 0;
1905 	int i, j, rv;
1906 
1907 	if (!ipv4_is_multicast(addr))
1908 		return -EINVAL;
1909 
1910 	rtnl_lock();
1911 
1912 	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
1913 	imr.imr_address.s_addr = mreqs->imr_interface;
1914 	imr.imr_ifindex = ifindex;
1915 	in_dev = ip_mc_find_dev(net, &imr);
1916 
1917 	if (!in_dev) {
1918 		err = -ENODEV;
1919 		goto done;
1920 	}
1921 	err = -EADDRNOTAVAIL;
1922 
1923 	for_each_pmc_rtnl(inet, pmc) {
1924 		if ((pmc->multi.imr_multiaddr.s_addr ==
1925 		     imr.imr_multiaddr.s_addr) &&
1926 		    (pmc->multi.imr_ifindex == imr.imr_ifindex))
1927 			break;
1928 	}
1929 	if (!pmc) {		/* must have a prior join */
1930 		err = -EINVAL;
1931 		goto done;
1932 	}
1933 	/* if a source filter was set, must be the same mode as before */
1934 	if (pmc->sflist) {
1935 		if (pmc->sfmode != omode) {
1936 			err = -EINVAL;
1937 			goto done;
1938 		}
1939 	} else if (pmc->sfmode != omode) {
1940 		/* allow mode switches for empty-set filters */
1941 		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
1942 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
1943 			NULL, 0);
1944 		pmc->sfmode = omode;
1945 	}
1946 
1947 	psl = rtnl_dereference(pmc->sflist);
1948 	if (!add) {
1949 		if (!psl)
1950 			goto done;	/* err = -EADDRNOTAVAIL */
1951 		rv = !0;
1952 		for (i=0; i<psl->sl_count; i++) {
1953 			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1954 				sizeof(__be32));
1955 			if (rv == 0)
1956 				break;
1957 		}
1958 		if (rv)		/* source not found */
1959 			goto done;	/* err = -EADDRNOTAVAIL */
1960 
1961 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
1962 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
1963 			leavegroup = 1;
1964 			goto done;
1965 		}
1966 
1967 		/* update the interface filter */
1968 		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1969 			&mreqs->imr_sourceaddr, 1);
1970 
1971 		for (j=i+1; j<psl->sl_count; j++)
1972 			psl->sl_addr[j-1] = psl->sl_addr[j];
1973 		psl->sl_count--;
1974 		err = 0;
1975 		goto done;
1976 	}
1977 	/* else, add a new source to the filter */
1978 
1979 	if (psl && psl->sl_count >= sysctl_igmp_max_msf) {
1980 		err = -ENOBUFS;
1981 		goto done;
1982 	}
1983 	if (!psl || psl->sl_count == psl->sl_max) {
1984 		struct ip_sf_socklist *newpsl;
1985 		int count = IP_SFBLOCK;
1986 
1987 		if (psl)
1988 			count += psl->sl_max;
1989 		newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
1990 		if (!newpsl) {
1991 			err = -ENOBUFS;
1992 			goto done;
1993 		}
1994 		newpsl->sl_max = count;
1995 		newpsl->sl_count = count - IP_SFBLOCK;
1996 		if (psl) {
1997 			for (i=0; i<psl->sl_count; i++)
1998 				newpsl->sl_addr[i] = psl->sl_addr[i];
1999 			/* decrease mem now to avoid the memleak warning */
2000 			atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2001 			kfree_rcu(psl, rcu);
2002 		}
2003 		rcu_assign_pointer(pmc->sflist, newpsl);
2004 		psl = newpsl;
2005 	}
2006 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
2007 	for (i=0; i<psl->sl_count; i++) {
2008 		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2009 			sizeof(__be32));
2010 		if (rv == 0)
2011 			break;
2012 	}
2013 	if (rv == 0)		/* address already there is an error */
2014 		goto done;
2015 	for (j=psl->sl_count-1; j>=i; j--)
2016 		psl->sl_addr[j+1] = psl->sl_addr[j];
2017 	psl->sl_addr[i] = mreqs->imr_sourceaddr;
2018 	psl->sl_count++;
2019 	err = 0;
2020 	/* update the interface list */
2021 	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2022 		&mreqs->imr_sourceaddr, 1);
2023 done:
2024 	rtnl_unlock();
2025 	if (leavegroup)
2026 		return ip_mc_leave_group(sk, &imr);
2027 	return err;
2028 }
2029 
2030 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2031 {
2032 	int err = 0;
2033 	struct ip_mreqn	imr;
2034 	__be32 addr = msf->imsf_multiaddr;
2035 	struct ip_mc_socklist *pmc;
2036 	struct in_device *in_dev;
2037 	struct inet_sock *inet = inet_sk(sk);
2038 	struct ip_sf_socklist *newpsl, *psl;
2039 	struct net *net = sock_net(sk);
2040 	int leavegroup = 0;
2041 
2042 	if (!ipv4_is_multicast(addr))
2043 		return -EINVAL;
2044 	if (msf->imsf_fmode != MCAST_INCLUDE &&
2045 	    msf->imsf_fmode != MCAST_EXCLUDE)
2046 		return -EINVAL;
2047 
2048 	rtnl_lock();
2049 
2050 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2051 	imr.imr_address.s_addr = msf->imsf_interface;
2052 	imr.imr_ifindex = ifindex;
2053 	in_dev = ip_mc_find_dev(net, &imr);
2054 
2055 	if (!in_dev) {
2056 		err = -ENODEV;
2057 		goto done;
2058 	}
2059 
2060 	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2061 	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2062 		leavegroup = 1;
2063 		goto done;
2064 	}
2065 
2066 	for_each_pmc_rtnl(inet, pmc) {
2067 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2068 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2069 			break;
2070 	}
2071 	if (!pmc) {		/* must have a prior join */
2072 		err = -EINVAL;
2073 		goto done;
2074 	}
2075 	if (msf->imsf_numsrc) {
2076 		newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2077 							   GFP_KERNEL);
2078 		if (!newpsl) {
2079 			err = -ENOBUFS;
2080 			goto done;
2081 		}
2082 		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2083 		memcpy(newpsl->sl_addr, msf->imsf_slist,
2084 			msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2085 		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2086 			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2087 		if (err) {
2088 			sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2089 			goto done;
2090 		}
2091 	} else {
2092 		newpsl = NULL;
2093 		(void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2094 				     msf->imsf_fmode, 0, NULL, 0);
2095 	}
2096 	psl = rtnl_dereference(pmc->sflist);
2097 	if (psl) {
2098 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2099 			psl->sl_count, psl->sl_addr, 0);
2100 		/* decrease mem now to avoid the memleak warning */
2101 		atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2102 		kfree_rcu(psl, rcu);
2103 	} else
2104 		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2105 			0, NULL, 0);
2106 	rcu_assign_pointer(pmc->sflist, newpsl);
2107 	pmc->sfmode = msf->imsf_fmode;
2108 	err = 0;
2109 done:
2110 	rtnl_unlock();
2111 	if (leavegroup)
2112 		err = ip_mc_leave_group(sk, &imr);
2113 	return err;
2114 }
2115 
2116 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2117 	struct ip_msfilter __user *optval, int __user *optlen)
2118 {
2119 	int err, len, count, copycount;
2120 	struct ip_mreqn	imr;
2121 	__be32 addr = msf->imsf_multiaddr;
2122 	struct ip_mc_socklist *pmc;
2123 	struct in_device *in_dev;
2124 	struct inet_sock *inet = inet_sk(sk);
2125 	struct ip_sf_socklist *psl;
2126 	struct net *net = sock_net(sk);
2127 
2128 	if (!ipv4_is_multicast(addr))
2129 		return -EINVAL;
2130 
2131 	rtnl_lock();
2132 
2133 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2134 	imr.imr_address.s_addr = msf->imsf_interface;
2135 	imr.imr_ifindex = 0;
2136 	in_dev = ip_mc_find_dev(net, &imr);
2137 
2138 	if (!in_dev) {
2139 		err = -ENODEV;
2140 		goto done;
2141 	}
2142 	err = -EADDRNOTAVAIL;
2143 
2144 	for_each_pmc_rtnl(inet, pmc) {
2145 		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2146 		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2147 			break;
2148 	}
2149 	if (!pmc)		/* must have a prior join */
2150 		goto done;
2151 	msf->imsf_fmode = pmc->sfmode;
2152 	psl = rtnl_dereference(pmc->sflist);
2153 	rtnl_unlock();
2154 	if (!psl) {
2155 		len = 0;
2156 		count = 0;
2157 	} else {
2158 		count = psl->sl_count;
2159 	}
2160 	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2161 	len = copycount * sizeof(psl->sl_addr[0]);
2162 	msf->imsf_numsrc = count;
2163 	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2164 	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2165 		return -EFAULT;
2166 	}
2167 	if (len &&
2168 	    copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2169 		return -EFAULT;
2170 	return 0;
2171 done:
2172 	rtnl_unlock();
2173 	return err;
2174 }
2175 
2176 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2177 	struct group_filter __user *optval, int __user *optlen)
2178 {
2179 	int err, i, count, copycount;
2180 	struct sockaddr_in *psin;
2181 	__be32 addr;
2182 	struct ip_mc_socklist *pmc;
2183 	struct inet_sock *inet = inet_sk(sk);
2184 	struct ip_sf_socklist *psl;
2185 
2186 	psin = (struct sockaddr_in *)&gsf->gf_group;
2187 	if (psin->sin_family != AF_INET)
2188 		return -EINVAL;
2189 	addr = psin->sin_addr.s_addr;
2190 	if (!ipv4_is_multicast(addr))
2191 		return -EINVAL;
2192 
2193 	rtnl_lock();
2194 
2195 	err = -EADDRNOTAVAIL;
2196 
2197 	for_each_pmc_rtnl(inet, pmc) {
2198 		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2199 		    pmc->multi.imr_ifindex == gsf->gf_interface)
2200 			break;
2201 	}
2202 	if (!pmc)		/* must have a prior join */
2203 		goto done;
2204 	gsf->gf_fmode = pmc->sfmode;
2205 	psl = rtnl_dereference(pmc->sflist);
2206 	rtnl_unlock();
2207 	count = psl ? psl->sl_count : 0;
2208 	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2209 	gsf->gf_numsrc = count;
2210 	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2211 	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2212 		return -EFAULT;
2213 	}
2214 	for (i=0; i<copycount; i++) {
2215 		struct sockaddr_storage ss;
2216 
2217 		psin = (struct sockaddr_in *)&ss;
2218 		memset(&ss, 0, sizeof(ss));
2219 		psin->sin_family = AF_INET;
2220 		psin->sin_addr.s_addr = psl->sl_addr[i];
2221 		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2222 			return -EFAULT;
2223 	}
2224 	return 0;
2225 done:
2226 	rtnl_unlock();
2227 	return err;
2228 }
2229 
2230 /*
2231  * check if a multicast source filter allows delivery for a given <src,dst,intf>
2232  */
2233 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif)
2234 {
2235 	struct inet_sock *inet = inet_sk(sk);
2236 	struct ip_mc_socklist *pmc;
2237 	struct ip_sf_socklist *psl;
2238 	int i;
2239 	int ret;
2240 
2241 	ret = 1;
2242 	if (!ipv4_is_multicast(loc_addr))
2243 		goto out;
2244 
2245 	rcu_read_lock();
2246 	for_each_pmc_rcu(inet, pmc) {
2247 		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2248 		    pmc->multi.imr_ifindex == dif)
2249 			break;
2250 	}
2251 	ret = inet->mc_all;
2252 	if (!pmc)
2253 		goto unlock;
2254 	psl = rcu_dereference(pmc->sflist);
2255 	ret = (pmc->sfmode == MCAST_EXCLUDE);
2256 	if (!psl)
2257 		goto unlock;
2258 
2259 	for (i=0; i<psl->sl_count; i++) {
2260 		if (psl->sl_addr[i] == rmt_addr)
2261 			break;
2262 	}
2263 	ret = 0;
2264 	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2265 		goto unlock;
2266 	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2267 		goto unlock;
2268 	ret = 1;
2269 unlock:
2270 	rcu_read_unlock();
2271 out:
2272 	return ret;
2273 }
2274 
2275 /*
2276  *	A socket is closing.
2277  */
2278 
2279 void ip_mc_drop_socket(struct sock *sk)
2280 {
2281 	struct inet_sock *inet = inet_sk(sk);
2282 	struct ip_mc_socklist *iml;
2283 	struct net *net = sock_net(sk);
2284 
2285 	if (inet->mc_list == NULL)
2286 		return;
2287 
2288 	rtnl_lock();
2289 	while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2290 		struct in_device *in_dev;
2291 
2292 		inet->mc_list = iml->next_rcu;
2293 		in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2294 		(void) ip_mc_leave_src(sk, iml, in_dev);
2295 		if (in_dev != NULL)
2296 			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2297 		/* decrease mem now to avoid the memleak warning */
2298 		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2299 		kfree_rcu(iml, rcu);
2300 	}
2301 	rtnl_unlock();
2302 }
2303 
2304 /* called with rcu_read_lock() */
2305 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u16 proto)
2306 {
2307 	struct ip_mc_list *im;
2308 	struct ip_sf_list *psf;
2309 	int rv = 0;
2310 
2311 	for_each_pmc_rcu(in_dev, im) {
2312 		if (im->multiaddr == mc_addr)
2313 			break;
2314 	}
2315 	if (im && proto == IPPROTO_IGMP) {
2316 		rv = 1;
2317 	} else if (im) {
2318 		if (src_addr) {
2319 			for (psf=im->sources; psf; psf=psf->sf_next) {
2320 				if (psf->sf_inaddr == src_addr)
2321 					break;
2322 			}
2323 			if (psf)
2324 				rv = psf->sf_count[MCAST_INCLUDE] ||
2325 					psf->sf_count[MCAST_EXCLUDE] !=
2326 					im->sfcount[MCAST_EXCLUDE];
2327 			else
2328 				rv = im->sfcount[MCAST_EXCLUDE] != 0;
2329 		} else
2330 			rv = 1; /* unspecified source; tentatively allow */
2331 	}
2332 	return rv;
2333 }
2334 
2335 #if defined(CONFIG_PROC_FS)
2336 struct igmp_mc_iter_state {
2337 	struct seq_net_private p;
2338 	struct net_device *dev;
2339 	struct in_device *in_dev;
2340 };
2341 
2342 #define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2343 
2344 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2345 {
2346 	struct net *net = seq_file_net(seq);
2347 	struct ip_mc_list *im = NULL;
2348 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2349 
2350 	state->in_dev = NULL;
2351 	for_each_netdev_rcu(net, state->dev) {
2352 		struct in_device *in_dev;
2353 
2354 		in_dev = __in_dev_get_rcu(state->dev);
2355 		if (!in_dev)
2356 			continue;
2357 		im = rcu_dereference(in_dev->mc_list);
2358 		if (im) {
2359 			state->in_dev = in_dev;
2360 			break;
2361 		}
2362 	}
2363 	return im;
2364 }
2365 
2366 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2367 {
2368 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2369 
2370 	im = rcu_dereference(im->next_rcu);
2371 	while (!im) {
2372 		state->dev = next_net_device_rcu(state->dev);
2373 		if (!state->dev) {
2374 			state->in_dev = NULL;
2375 			break;
2376 		}
2377 		state->in_dev = __in_dev_get_rcu(state->dev);
2378 		if (!state->in_dev)
2379 			continue;
2380 		im = rcu_dereference(state->in_dev->mc_list);
2381 	}
2382 	return im;
2383 }
2384 
2385 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2386 {
2387 	struct ip_mc_list *im = igmp_mc_get_first(seq);
2388 	if (im)
2389 		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2390 			--pos;
2391 	return pos ? NULL : im;
2392 }
2393 
2394 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2395 	__acquires(rcu)
2396 {
2397 	rcu_read_lock();
2398 	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2399 }
2400 
2401 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2402 {
2403 	struct ip_mc_list *im;
2404 	if (v == SEQ_START_TOKEN)
2405 		im = igmp_mc_get_first(seq);
2406 	else
2407 		im = igmp_mc_get_next(seq, v);
2408 	++*pos;
2409 	return im;
2410 }
2411 
2412 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2413 	__releases(rcu)
2414 {
2415 	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2416 
2417 	state->in_dev = NULL;
2418 	state->dev = NULL;
2419 	rcu_read_unlock();
2420 }
2421 
2422 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2423 {
2424 	if (v == SEQ_START_TOKEN)
2425 		seq_puts(seq,
2426 			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2427 	else {
2428 		struct ip_mc_list *im = (struct ip_mc_list *)v;
2429 		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2430 		char   *querier;
2431 #ifdef CONFIG_IP_MULTICAST
2432 		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2433 			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2434 			  "V3";
2435 #else
2436 		querier = "NONE";
2437 #endif
2438 
2439 		if (rcu_dereference(state->in_dev->mc_list) == im) {
2440 			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2441 				   state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2442 		}
2443 
2444 		seq_printf(seq,
2445 			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2446 			   im->multiaddr, im->users,
2447 			   im->tm_running, im->tm_running ?
2448 			   jiffies_to_clock_t(im->timer.expires-jiffies) : 0,
2449 			   im->reporter);
2450 	}
2451 	return 0;
2452 }
2453 
2454 static const struct seq_operations igmp_mc_seq_ops = {
2455 	.start	=	igmp_mc_seq_start,
2456 	.next	=	igmp_mc_seq_next,
2457 	.stop	=	igmp_mc_seq_stop,
2458 	.show	=	igmp_mc_seq_show,
2459 };
2460 
2461 static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2462 {
2463 	return seq_open_net(inode, file, &igmp_mc_seq_ops,
2464 			sizeof(struct igmp_mc_iter_state));
2465 }
2466 
2467 static const struct file_operations igmp_mc_seq_fops = {
2468 	.owner		=	THIS_MODULE,
2469 	.open		=	igmp_mc_seq_open,
2470 	.read		=	seq_read,
2471 	.llseek		=	seq_lseek,
2472 	.release	=	seq_release_net,
2473 };
2474 
2475 struct igmp_mcf_iter_state {
2476 	struct seq_net_private p;
2477 	struct net_device *dev;
2478 	struct in_device *idev;
2479 	struct ip_mc_list *im;
2480 };
2481 
2482 #define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2483 
2484 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2485 {
2486 	struct net *net = seq_file_net(seq);
2487 	struct ip_sf_list *psf = NULL;
2488 	struct ip_mc_list *im = NULL;
2489 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2490 
2491 	state->idev = NULL;
2492 	state->im = NULL;
2493 	for_each_netdev_rcu(net, state->dev) {
2494 		struct in_device *idev;
2495 		idev = __in_dev_get_rcu(state->dev);
2496 		if (unlikely(idev == NULL))
2497 			continue;
2498 		im = rcu_dereference(idev->mc_list);
2499 		if (likely(im != NULL)) {
2500 			spin_lock_bh(&im->lock);
2501 			psf = im->sources;
2502 			if (likely(psf != NULL)) {
2503 				state->im = im;
2504 				state->idev = idev;
2505 				break;
2506 			}
2507 			spin_unlock_bh(&im->lock);
2508 		}
2509 	}
2510 	return psf;
2511 }
2512 
2513 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2514 {
2515 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2516 
2517 	psf = psf->sf_next;
2518 	while (!psf) {
2519 		spin_unlock_bh(&state->im->lock);
2520 		state->im = state->im->next;
2521 		while (!state->im) {
2522 			state->dev = next_net_device_rcu(state->dev);
2523 			if (!state->dev) {
2524 				state->idev = NULL;
2525 				goto out;
2526 			}
2527 			state->idev = __in_dev_get_rcu(state->dev);
2528 			if (!state->idev)
2529 				continue;
2530 			state->im = rcu_dereference(state->idev->mc_list);
2531 		}
2532 		if (!state->im)
2533 			break;
2534 		spin_lock_bh(&state->im->lock);
2535 		psf = state->im->sources;
2536 	}
2537 out:
2538 	return psf;
2539 }
2540 
2541 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2542 {
2543 	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2544 	if (psf)
2545 		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2546 			--pos;
2547 	return pos ? NULL : psf;
2548 }
2549 
2550 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2551 	__acquires(rcu)
2552 {
2553 	rcu_read_lock();
2554 	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2555 }
2556 
2557 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2558 {
2559 	struct ip_sf_list *psf;
2560 	if (v == SEQ_START_TOKEN)
2561 		psf = igmp_mcf_get_first(seq);
2562 	else
2563 		psf = igmp_mcf_get_next(seq, v);
2564 	++*pos;
2565 	return psf;
2566 }
2567 
2568 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2569 	__releases(rcu)
2570 {
2571 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2572 	if (likely(state->im != NULL)) {
2573 		spin_unlock_bh(&state->im->lock);
2574 		state->im = NULL;
2575 	}
2576 	state->idev = NULL;
2577 	state->dev = NULL;
2578 	rcu_read_unlock();
2579 }
2580 
2581 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2582 {
2583 	struct ip_sf_list *psf = (struct ip_sf_list *)v;
2584 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2585 
2586 	if (v == SEQ_START_TOKEN) {
2587 		seq_printf(seq,
2588 			   "%3s %6s "
2589 			   "%10s %10s %6s %6s\n", "Idx",
2590 			   "Device", "MCA",
2591 			   "SRC", "INC", "EXC");
2592 	} else {
2593 		seq_printf(seq,
2594 			   "%3d %6.6s 0x%08x "
2595 			   "0x%08x %6lu %6lu\n",
2596 			   state->dev->ifindex, state->dev->name,
2597 			   ntohl(state->im->multiaddr),
2598 			   ntohl(psf->sf_inaddr),
2599 			   psf->sf_count[MCAST_INCLUDE],
2600 			   psf->sf_count[MCAST_EXCLUDE]);
2601 	}
2602 	return 0;
2603 }
2604 
2605 static const struct seq_operations igmp_mcf_seq_ops = {
2606 	.start	=	igmp_mcf_seq_start,
2607 	.next	=	igmp_mcf_seq_next,
2608 	.stop	=	igmp_mcf_seq_stop,
2609 	.show	=	igmp_mcf_seq_show,
2610 };
2611 
2612 static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2613 {
2614 	return seq_open_net(inode, file, &igmp_mcf_seq_ops,
2615 			sizeof(struct igmp_mcf_iter_state));
2616 }
2617 
2618 static const struct file_operations igmp_mcf_seq_fops = {
2619 	.owner		=	THIS_MODULE,
2620 	.open		=	igmp_mcf_seq_open,
2621 	.read		=	seq_read,
2622 	.llseek		=	seq_lseek,
2623 	.release	=	seq_release_net,
2624 };
2625 
2626 static int __net_init igmp_net_init(struct net *net)
2627 {
2628 	struct proc_dir_entry *pde;
2629 
2630 	pde = proc_net_fops_create(net, "igmp", S_IRUGO, &igmp_mc_seq_fops);
2631 	if (!pde)
2632 		goto out_igmp;
2633 	pde = proc_net_fops_create(net, "mcfilter", S_IRUGO, &igmp_mcf_seq_fops);
2634 	if (!pde)
2635 		goto out_mcfilter;
2636 	return 0;
2637 
2638 out_mcfilter:
2639 	proc_net_remove(net, "igmp");
2640 out_igmp:
2641 	return -ENOMEM;
2642 }
2643 
2644 static void __net_exit igmp_net_exit(struct net *net)
2645 {
2646 	proc_net_remove(net, "mcfilter");
2647 	proc_net_remove(net, "igmp");
2648 }
2649 
2650 static struct pernet_operations igmp_net_ops = {
2651 	.init = igmp_net_init,
2652 	.exit = igmp_net_exit,
2653 };
2654 
2655 int __init igmp_mc_proc_init(void)
2656 {
2657 	return register_pernet_subsys(&igmp_net_ops);
2658 }
2659 #endif
2660