igmp.c revision 2430aa85de8343662e8496dac9f9e4dade680023
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(in_dev->dev->nd_net, 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(in_dev->dev->nd_net, 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
143static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im);
144static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr);
145static void igmpv3_clear_delrec(struct in_device *in_dev);
146static int sf_setstate(struct ip_mc_list *pmc);
147static void sf_markstate(struct ip_mc_list *pmc);
148#endif
149static void ip_mc_clear_src(struct ip_mc_list *pmc);
150static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
151			 int sfcount, __be32 *psfsrc, int delta);
152
153static 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
167static __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 */
179static 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
188static 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
197static 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
205static 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
230static 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
274static int
275igmp_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
288static 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(&init_net, &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
350static int igmpv3_sendpack(struct sk_buff *skb)
351{
352	struct igmphdr *pig = igmp_hdr(skb);
353	const int igmplen = skb->tail - skb->transport_header;
354
355	pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
356
357	return ip_local_out(skb);
358}
359
360static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
361{
362	return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc,type,gdel,sdel);
363}
364
365static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
366	int type, struct igmpv3_grec **ppgr)
367{
368	struct net_device *dev = pmc->interface->dev;
369	struct igmpv3_report *pih;
370	struct igmpv3_grec *pgr;
371
372	if (!skb)
373		skb = igmpv3_newpack(dev, dev->mtu);
374	if (!skb)
375		return NULL;
376	pgr = (struct igmpv3_grec *)skb_put(skb, sizeof(struct igmpv3_grec));
377	pgr->grec_type = type;
378	pgr->grec_auxwords = 0;
379	pgr->grec_nsrcs = 0;
380	pgr->grec_mca = pmc->multiaddr;
381	pih = igmpv3_report_hdr(skb);
382	pih->ngrec = htons(ntohs(pih->ngrec)+1);
383	*ppgr = pgr;
384	return skb;
385}
386
387#define AVAILABLE(skb) ((skb) ? ((skb)->dev ? (skb)->dev->mtu - (skb)->len : \
388	skb_tailroom(skb)) : 0)
389
390static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
391	int type, int gdeleted, int sdeleted)
392{
393	struct net_device *dev = pmc->interface->dev;
394	struct igmpv3_report *pih;
395	struct igmpv3_grec *pgr = NULL;
396	struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
397	int scount, stotal, first, isquery, truncate;
398
399	if (pmc->multiaddr == IGMP_ALL_HOSTS)
400		return skb;
401
402	isquery = type == IGMPV3_MODE_IS_INCLUDE ||
403		  type == IGMPV3_MODE_IS_EXCLUDE;
404	truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
405		    type == IGMPV3_CHANGE_TO_EXCLUDE;
406
407	stotal = scount = 0;
408
409	psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
410
411	if (!*psf_list)
412		goto empty_source;
413
414	pih = skb ? igmpv3_report_hdr(skb) : NULL;
415
416	/* EX and TO_EX get a fresh packet, if needed */
417	if (truncate) {
418		if (pih && pih->ngrec &&
419		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
420			if (skb)
421				igmpv3_sendpack(skb);
422			skb = igmpv3_newpack(dev, dev->mtu);
423		}
424	}
425	first = 1;
426	psf_prev = NULL;
427	for (psf=*psf_list; psf; psf=psf_next) {
428		__be32 *psrc;
429
430		psf_next = psf->sf_next;
431
432		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
433			psf_prev = psf;
434			continue;
435		}
436
437		/* clear marks on query responses */
438		if (isquery)
439			psf->sf_gsresp = 0;
440
441		if (AVAILABLE(skb) < sizeof(__be32) +
442		    first*sizeof(struct igmpv3_grec)) {
443			if (truncate && !first)
444				break;	 /* truncate these */
445			if (pgr)
446				pgr->grec_nsrcs = htons(scount);
447			if (skb)
448				igmpv3_sendpack(skb);
449			skb = igmpv3_newpack(dev, dev->mtu);
450			first = 1;
451			scount = 0;
452		}
453		if (first) {
454			skb = add_grhead(skb, pmc, type, &pgr);
455			first = 0;
456		}
457		if (!skb)
458			return NULL;
459		psrc = (__be32 *)skb_put(skb, sizeof(__be32));
460		*psrc = psf->sf_inaddr;
461		scount++; stotal++;
462		if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
463		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
464			psf->sf_crcount--;
465			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
466				if (psf_prev)
467					psf_prev->sf_next = psf->sf_next;
468				else
469					*psf_list = psf->sf_next;
470				kfree(psf);
471				continue;
472			}
473		}
474		psf_prev = psf;
475	}
476
477empty_source:
478	if (!stotal) {
479		if (type == IGMPV3_ALLOW_NEW_SOURCES ||
480		    type == IGMPV3_BLOCK_OLD_SOURCES)
481			return skb;
482		if (pmc->crcount || isquery) {
483			/* make sure we have room for group header */
484			if (skb && AVAILABLE(skb)<sizeof(struct igmpv3_grec)) {
485				igmpv3_sendpack(skb);
486				skb = NULL; /* add_grhead will get a new one */
487			}
488			skb = add_grhead(skb, pmc, type, &pgr);
489		}
490	}
491	if (pgr)
492		pgr->grec_nsrcs = htons(scount);
493
494	if (isquery)
495		pmc->gsquery = 0;	/* clear query state on report */
496	return skb;
497}
498
499static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
500{
501	struct sk_buff *skb = NULL;
502	int type;
503
504	if (!pmc) {
505		read_lock(&in_dev->mc_list_lock);
506		for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
507			if (pmc->multiaddr == IGMP_ALL_HOSTS)
508				continue;
509			spin_lock_bh(&pmc->lock);
510			if (pmc->sfcount[MCAST_EXCLUDE])
511				type = IGMPV3_MODE_IS_EXCLUDE;
512			else
513				type = IGMPV3_MODE_IS_INCLUDE;
514			skb = add_grec(skb, pmc, type, 0, 0);
515			spin_unlock_bh(&pmc->lock);
516		}
517		read_unlock(&in_dev->mc_list_lock);
518	} else {
519		spin_lock_bh(&pmc->lock);
520		if (pmc->sfcount[MCAST_EXCLUDE])
521			type = IGMPV3_MODE_IS_EXCLUDE;
522		else
523			type = IGMPV3_MODE_IS_INCLUDE;
524		skb = add_grec(skb, pmc, type, 0, 0);
525		spin_unlock_bh(&pmc->lock);
526	}
527	if (!skb)
528		return 0;
529	return igmpv3_sendpack(skb);
530}
531
532/*
533 * remove zero-count source records from a source filter list
534 */
535static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
536{
537	struct ip_sf_list *psf_prev, *psf_next, *psf;
538
539	psf_prev = NULL;
540	for (psf=*ppsf; psf; psf = psf_next) {
541		psf_next = psf->sf_next;
542		if (psf->sf_crcount == 0) {
543			if (psf_prev)
544				psf_prev->sf_next = psf->sf_next;
545			else
546				*ppsf = psf->sf_next;
547			kfree(psf);
548		} else
549			psf_prev = psf;
550	}
551}
552
553static void igmpv3_send_cr(struct in_device *in_dev)
554{
555	struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
556	struct sk_buff *skb = NULL;
557	int type, dtype;
558
559	read_lock(&in_dev->mc_list_lock);
560	spin_lock_bh(&in_dev->mc_tomb_lock);
561
562	/* deleted MCA's */
563	pmc_prev = NULL;
564	for (pmc=in_dev->mc_tomb; pmc; pmc=pmc_next) {
565		pmc_next = pmc->next;
566		if (pmc->sfmode == MCAST_INCLUDE) {
567			type = IGMPV3_BLOCK_OLD_SOURCES;
568			dtype = IGMPV3_BLOCK_OLD_SOURCES;
569			skb = add_grec(skb, pmc, type, 1, 0);
570			skb = add_grec(skb, pmc, dtype, 1, 1);
571		}
572		if (pmc->crcount) {
573			if (pmc->sfmode == MCAST_EXCLUDE) {
574				type = IGMPV3_CHANGE_TO_INCLUDE;
575				skb = add_grec(skb, pmc, type, 1, 0);
576			}
577			pmc->crcount--;
578			if (pmc->crcount == 0) {
579				igmpv3_clear_zeros(&pmc->tomb);
580				igmpv3_clear_zeros(&pmc->sources);
581			}
582		}
583		if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
584			if (pmc_prev)
585				pmc_prev->next = pmc_next;
586			else
587				in_dev->mc_tomb = pmc_next;
588			in_dev_put(pmc->interface);
589			kfree(pmc);
590		} else
591			pmc_prev = pmc;
592	}
593	spin_unlock_bh(&in_dev->mc_tomb_lock);
594
595	/* change recs */
596	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
597		spin_lock_bh(&pmc->lock);
598		if (pmc->sfcount[MCAST_EXCLUDE]) {
599			type = IGMPV3_BLOCK_OLD_SOURCES;
600			dtype = IGMPV3_ALLOW_NEW_SOURCES;
601		} else {
602			type = IGMPV3_ALLOW_NEW_SOURCES;
603			dtype = IGMPV3_BLOCK_OLD_SOURCES;
604		}
605		skb = add_grec(skb, pmc, type, 0, 0);
606		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
607
608		/* filter mode changes */
609		if (pmc->crcount) {
610			if (pmc->sfmode == MCAST_EXCLUDE)
611				type = IGMPV3_CHANGE_TO_EXCLUDE;
612			else
613				type = IGMPV3_CHANGE_TO_INCLUDE;
614			skb = add_grec(skb, pmc, type, 0, 0);
615			pmc->crcount--;
616		}
617		spin_unlock_bh(&pmc->lock);
618	}
619	read_unlock(&in_dev->mc_list_lock);
620
621	if (!skb)
622		return;
623	(void) igmpv3_sendpack(skb);
624}
625
626static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
627	int type)
628{
629	struct sk_buff *skb;
630	struct iphdr *iph;
631	struct igmphdr *ih;
632	struct rtable *rt;
633	struct net_device *dev = in_dev->dev;
634	__be32	group = pmc ? pmc->multiaddr : 0;
635	__be32	dst;
636
637	if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
638		return igmpv3_send_report(in_dev, pmc);
639	else if (type == IGMP_HOST_LEAVE_MESSAGE)
640		dst = IGMP_ALL_ROUTER;
641	else
642		dst = group;
643
644	{
645		struct flowi fl = { .oif = dev->ifindex,
646				    .nl_u = { .ip4_u = { .daddr = dst } },
647				    .proto = IPPROTO_IGMP };
648		if (ip_route_output_key(&init_net, &rt, &fl))
649			return -1;
650	}
651	if (rt->rt_src == 0) {
652		ip_rt_put(rt);
653		return -1;
654	}
655
656	skb=alloc_skb(IGMP_SIZE+LL_RESERVED_SPACE(dev), GFP_ATOMIC);
657	if (skb == NULL) {
658		ip_rt_put(rt);
659		return -1;
660	}
661
662	skb->dst = &rt->u.dst;
663
664	skb_reserve(skb, LL_RESERVED_SPACE(dev));
665
666	skb_reset_network_header(skb);
667	iph = ip_hdr(skb);
668	skb_put(skb, sizeof(struct iphdr) + 4);
669
670	iph->version  = 4;
671	iph->ihl      = (sizeof(struct iphdr)+4)>>2;
672	iph->tos      = 0xc0;
673	iph->frag_off = htons(IP_DF);
674	iph->ttl      = 1;
675	iph->daddr    = dst;
676	iph->saddr    = rt->rt_src;
677	iph->protocol = IPPROTO_IGMP;
678	ip_select_ident(iph, &rt->u.dst, NULL);
679	((u8*)&iph[1])[0] = IPOPT_RA;
680	((u8*)&iph[1])[1] = 4;
681	((u8*)&iph[1])[2] = 0;
682	((u8*)&iph[1])[3] = 0;
683
684	ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
685	ih->type=type;
686	ih->code=0;
687	ih->csum=0;
688	ih->group=group;
689	ih->csum=ip_compute_csum((void *)ih, sizeof(struct igmphdr));
690
691	return ip_local_out(skb);
692}
693
694static void igmp_gq_timer_expire(unsigned long data)
695{
696	struct in_device *in_dev = (struct in_device *)data;
697
698	in_dev->mr_gq_running = 0;
699	igmpv3_send_report(in_dev, NULL);
700	__in_dev_put(in_dev);
701}
702
703static void igmp_ifc_timer_expire(unsigned long data)
704{
705	struct in_device *in_dev = (struct in_device *)data;
706
707	igmpv3_send_cr(in_dev);
708	if (in_dev->mr_ifc_count) {
709		in_dev->mr_ifc_count--;
710		igmp_ifc_start_timer(in_dev, IGMP_Unsolicited_Report_Interval);
711	}
712	__in_dev_put(in_dev);
713}
714
715static void igmp_ifc_event(struct in_device *in_dev)
716{
717	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
718		return;
719	in_dev->mr_ifc_count = in_dev->mr_qrv ? in_dev->mr_qrv :
720		IGMP_Unsolicited_Report_Count;
721	igmp_ifc_start_timer(in_dev, 1);
722}
723
724
725static void igmp_timer_expire(unsigned long data)
726{
727	struct ip_mc_list *im=(struct ip_mc_list *)data;
728	struct in_device *in_dev = im->interface;
729
730	spin_lock(&im->lock);
731	im->tm_running=0;
732
733	if (im->unsolicit_count) {
734		im->unsolicit_count--;
735		igmp_start_timer(im, IGMP_Unsolicited_Report_Interval);
736	}
737	im->reporter = 1;
738	spin_unlock(&im->lock);
739
740	if (IGMP_V1_SEEN(in_dev))
741		igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
742	else if (IGMP_V2_SEEN(in_dev))
743		igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
744	else
745		igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
746
747	ip_ma_put(im);
748}
749
750/* mark EXCLUDE-mode sources */
751static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
752{
753	struct ip_sf_list *psf;
754	int i, scount;
755
756	scount = 0;
757	for (psf=pmc->sources; psf; psf=psf->sf_next) {
758		if (scount == nsrcs)
759			break;
760		for (i=0; i<nsrcs; i++) {
761			/* skip inactive filters */
762			if (pmc->sfcount[MCAST_INCLUDE] ||
763			    pmc->sfcount[MCAST_EXCLUDE] !=
764			    psf->sf_count[MCAST_EXCLUDE])
765				continue;
766			if (srcs[i] == psf->sf_inaddr) {
767				scount++;
768				break;
769			}
770		}
771	}
772	pmc->gsquery = 0;
773	if (scount == nsrcs)	/* all sources excluded */
774		return 0;
775	return 1;
776}
777
778static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
779{
780	struct ip_sf_list *psf;
781	int i, scount;
782
783	if (pmc->sfmode == MCAST_EXCLUDE)
784		return igmp_xmarksources(pmc, nsrcs, srcs);
785
786	/* mark INCLUDE-mode sources */
787	scount = 0;
788	for (psf=pmc->sources; psf; psf=psf->sf_next) {
789		if (scount == nsrcs)
790			break;
791		for (i=0; i<nsrcs; i++)
792			if (srcs[i] == psf->sf_inaddr) {
793				psf->sf_gsresp = 1;
794				scount++;
795				break;
796			}
797	}
798	if (!scount) {
799		pmc->gsquery = 0;
800		return 0;
801	}
802	pmc->gsquery = 1;
803	return 1;
804}
805
806static void igmp_heard_report(struct in_device *in_dev, __be32 group)
807{
808	struct ip_mc_list *im;
809
810	/* Timers are only set for non-local groups */
811
812	if (group == IGMP_ALL_HOSTS)
813		return;
814
815	read_lock(&in_dev->mc_list_lock);
816	for (im=in_dev->mc_list; im!=NULL; im=im->next) {
817		if (im->multiaddr == group) {
818			igmp_stop_timer(im);
819			break;
820		}
821	}
822	read_unlock(&in_dev->mc_list_lock);
823}
824
825static void igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
826	int len)
827{
828	struct igmphdr 		*ih = igmp_hdr(skb);
829	struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
830	struct ip_mc_list	*im;
831	__be32			group = ih->group;
832	int			max_delay;
833	int			mark = 0;
834
835
836	if (len == 8) {
837		if (ih->code == 0) {
838			/* Alas, old v1 router presents here. */
839
840			max_delay = IGMP_Query_Response_Interval;
841			in_dev->mr_v1_seen = jiffies +
842				IGMP_V1_Router_Present_Timeout;
843			group = 0;
844		} else {
845			/* v2 router present */
846			max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
847			in_dev->mr_v2_seen = jiffies +
848				IGMP_V2_Router_Present_Timeout;
849		}
850		/* cancel the interface change timer */
851		in_dev->mr_ifc_count = 0;
852		if (del_timer(&in_dev->mr_ifc_timer))
853			__in_dev_put(in_dev);
854		/* clear deleted report items */
855		igmpv3_clear_delrec(in_dev);
856	} else if (len < 12) {
857		return;	/* ignore bogus packet; freed by caller */
858	} else { /* v3 */
859		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
860			return;
861
862		ih3 = igmpv3_query_hdr(skb);
863		if (ih3->nsrcs) {
864			if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
865					   + ntohs(ih3->nsrcs)*sizeof(__be32)))
866				return;
867			ih3 = igmpv3_query_hdr(skb);
868		}
869
870		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
871		if (!max_delay)
872			max_delay = 1;	/* can't mod w/ 0 */
873		in_dev->mr_maxdelay = max_delay;
874		if (ih3->qrv)
875			in_dev->mr_qrv = ih3->qrv;
876		if (!group) { /* general query */
877			if (ih3->nsrcs)
878				return;	/* no sources allowed */
879			igmp_gq_start_timer(in_dev);
880			return;
881		}
882		/* mark sources to include, if group & source-specific */
883		mark = ih3->nsrcs != 0;
884	}
885
886	/*
887	 * - Start the timers in all of our membership records
888	 *   that the query applies to for the interface on
889	 *   which the query arrived excl. those that belong
890	 *   to a "local" group (224.0.0.X)
891	 * - For timers already running check if they need to
892	 *   be reset.
893	 * - Use the igmp->igmp_code field as the maximum
894	 *   delay possible
895	 */
896	read_lock(&in_dev->mc_list_lock);
897	for (im=in_dev->mc_list; im!=NULL; im=im->next) {
898		int changed;
899
900		if (group && group != im->multiaddr)
901			continue;
902		if (im->multiaddr == IGMP_ALL_HOSTS)
903			continue;
904		spin_lock_bh(&im->lock);
905		if (im->tm_running)
906			im->gsquery = im->gsquery && mark;
907		else
908			im->gsquery = mark;
909		changed = !im->gsquery ||
910			igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
911		spin_unlock_bh(&im->lock);
912		if (changed)
913			igmp_mod_timer(im, max_delay);
914	}
915	read_unlock(&in_dev->mc_list_lock);
916}
917
918int igmp_rcv(struct sk_buff *skb)
919{
920	/* This basically follows the spec line by line -- see RFC1112 */
921	struct igmphdr *ih;
922	struct in_device *in_dev = in_dev_get(skb->dev);
923	int len = skb->len;
924
925	if (in_dev == NULL)
926		goto drop;
927
928	if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
929		goto drop_ref;
930
931	switch (skb->ip_summed) {
932	case CHECKSUM_COMPLETE:
933		if (!csum_fold(skb->csum))
934			break;
935		/* fall through */
936	case CHECKSUM_NONE:
937		skb->csum = 0;
938		if (__skb_checksum_complete(skb))
939			goto drop_ref;
940	}
941
942	ih = igmp_hdr(skb);
943	switch (ih->type) {
944	case IGMP_HOST_MEMBERSHIP_QUERY:
945		igmp_heard_query(in_dev, skb, len);
946		break;
947	case IGMP_HOST_MEMBERSHIP_REPORT:
948	case IGMPV2_HOST_MEMBERSHIP_REPORT:
949	case IGMPV3_HOST_MEMBERSHIP_REPORT:
950		/* Is it our report looped back? */
951		if (((struct rtable*)skb->dst)->fl.iif == 0)
952			break;
953		/* don't rely on MC router hearing unicast reports */
954		if (skb->pkt_type == PACKET_MULTICAST ||
955		    skb->pkt_type == PACKET_BROADCAST)
956			igmp_heard_report(in_dev, ih->group);
957		break;
958	case IGMP_PIM:
959#ifdef CONFIG_IP_PIMSM_V1
960		in_dev_put(in_dev);
961		return pim_rcv_v1(skb);
962#endif
963	case IGMP_DVMRP:
964	case IGMP_TRACE:
965	case IGMP_HOST_LEAVE_MESSAGE:
966	case IGMP_MTRACE:
967	case IGMP_MTRACE_RESP:
968		break;
969	default:
970		break;
971	}
972
973drop_ref:
974	in_dev_put(in_dev);
975drop:
976	kfree_skb(skb);
977	return 0;
978}
979
980#endif
981
982
983/*
984 *	Add a filter to a device
985 */
986
987static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
988{
989	char buf[MAX_ADDR_LEN];
990	struct net_device *dev = in_dev->dev;
991
992	/* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
993	   We will get multicast token leakage, when IFF_MULTICAST
994	   is changed. This check should be done in dev->set_multicast_list
995	   routine. Something sort of:
996	   if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
997	   --ANK
998	   */
999	if (arp_mc_map(addr, buf, dev, 0) == 0)
1000		dev_mc_add(dev,buf,dev->addr_len,0);
1001}
1002
1003/*
1004 *	Remove a filter from a device
1005 */
1006
1007static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1008{
1009	char buf[MAX_ADDR_LEN];
1010	struct net_device *dev = in_dev->dev;
1011
1012	if (arp_mc_map(addr, buf, dev, 0) == 0)
1013		dev_mc_delete(dev,buf,dev->addr_len,0);
1014}
1015
1016#ifdef CONFIG_IP_MULTICAST
1017/*
1018 * deleted ip_mc_list manipulation
1019 */
1020static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1021{
1022	struct ip_mc_list *pmc;
1023
1024	/* this is an "ip_mc_list" for convenience; only the fields below
1025	 * are actually used. In particular, the refcnt and users are not
1026	 * used for management of the delete list. Using the same structure
1027	 * for deleted items allows change reports to use common code with
1028	 * non-deleted or query-response MCA's.
1029	 */
1030	pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
1031	if (!pmc)
1032		return;
1033	spin_lock_bh(&im->lock);
1034	pmc->interface = im->interface;
1035	in_dev_hold(in_dev);
1036	pmc->multiaddr = im->multiaddr;
1037	pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1038		IGMP_Unsolicited_Report_Count;
1039	pmc->sfmode = im->sfmode;
1040	if (pmc->sfmode == MCAST_INCLUDE) {
1041		struct ip_sf_list *psf;
1042
1043		pmc->tomb = im->tomb;
1044		pmc->sources = im->sources;
1045		im->tomb = im->sources = NULL;
1046		for (psf=pmc->sources; psf; psf=psf->sf_next)
1047			psf->sf_crcount = pmc->crcount;
1048	}
1049	spin_unlock_bh(&im->lock);
1050
1051	spin_lock_bh(&in_dev->mc_tomb_lock);
1052	pmc->next = in_dev->mc_tomb;
1053	in_dev->mc_tomb = pmc;
1054	spin_unlock_bh(&in_dev->mc_tomb_lock);
1055}
1056
1057static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr)
1058{
1059	struct ip_mc_list *pmc, *pmc_prev;
1060	struct ip_sf_list *psf, *psf_next;
1061
1062	spin_lock_bh(&in_dev->mc_tomb_lock);
1063	pmc_prev = NULL;
1064	for (pmc=in_dev->mc_tomb; pmc; pmc=pmc->next) {
1065		if (pmc->multiaddr == multiaddr)
1066			break;
1067		pmc_prev = pmc;
1068	}
1069	if (pmc) {
1070		if (pmc_prev)
1071			pmc_prev->next = pmc->next;
1072		else
1073			in_dev->mc_tomb = pmc->next;
1074	}
1075	spin_unlock_bh(&in_dev->mc_tomb_lock);
1076	if (pmc) {
1077		for (psf=pmc->tomb; psf; psf=psf_next) {
1078			psf_next = psf->sf_next;
1079			kfree(psf);
1080		}
1081		in_dev_put(pmc->interface);
1082		kfree(pmc);
1083	}
1084}
1085
1086static void igmpv3_clear_delrec(struct in_device *in_dev)
1087{
1088	struct ip_mc_list *pmc, *nextpmc;
1089
1090	spin_lock_bh(&in_dev->mc_tomb_lock);
1091	pmc = in_dev->mc_tomb;
1092	in_dev->mc_tomb = NULL;
1093	spin_unlock_bh(&in_dev->mc_tomb_lock);
1094
1095	for (; pmc; pmc = nextpmc) {
1096		nextpmc = pmc->next;
1097		ip_mc_clear_src(pmc);
1098		in_dev_put(pmc->interface);
1099		kfree(pmc);
1100	}
1101	/* clear dead sources, too */
1102	read_lock(&in_dev->mc_list_lock);
1103	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1104		struct ip_sf_list *psf, *psf_next;
1105
1106		spin_lock_bh(&pmc->lock);
1107		psf = pmc->tomb;
1108		pmc->tomb = NULL;
1109		spin_unlock_bh(&pmc->lock);
1110		for (; psf; psf=psf_next) {
1111			psf_next = psf->sf_next;
1112			kfree(psf);
1113		}
1114	}
1115	read_unlock(&in_dev->mc_list_lock);
1116}
1117#endif
1118
1119static void igmp_group_dropped(struct ip_mc_list *im)
1120{
1121	struct in_device *in_dev = im->interface;
1122#ifdef CONFIG_IP_MULTICAST
1123	int reporter;
1124#endif
1125
1126	if (im->loaded) {
1127		im->loaded = 0;
1128		ip_mc_filter_del(in_dev, im->multiaddr);
1129	}
1130
1131#ifdef CONFIG_IP_MULTICAST
1132	if (im->multiaddr == IGMP_ALL_HOSTS)
1133		return;
1134
1135	reporter = im->reporter;
1136	igmp_stop_timer(im);
1137
1138	if (!in_dev->dead) {
1139		if (IGMP_V1_SEEN(in_dev))
1140			goto done;
1141		if (IGMP_V2_SEEN(in_dev)) {
1142			if (reporter)
1143				igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1144			goto done;
1145		}
1146		/* IGMPv3 */
1147		igmpv3_add_delrec(in_dev, im);
1148
1149		igmp_ifc_event(in_dev);
1150	}
1151done:
1152#endif
1153	ip_mc_clear_src(im);
1154}
1155
1156static void igmp_group_added(struct ip_mc_list *im)
1157{
1158	struct in_device *in_dev = im->interface;
1159
1160	if (im->loaded == 0) {
1161		im->loaded = 1;
1162		ip_mc_filter_add(in_dev, im->multiaddr);
1163	}
1164
1165#ifdef CONFIG_IP_MULTICAST
1166	if (im->multiaddr == IGMP_ALL_HOSTS)
1167		return;
1168
1169	if (in_dev->dead)
1170		return;
1171	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1172		spin_lock_bh(&im->lock);
1173		igmp_start_timer(im, IGMP_Initial_Report_Delay);
1174		spin_unlock_bh(&im->lock);
1175		return;
1176	}
1177	/* else, v3 */
1178
1179	im->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1180		IGMP_Unsolicited_Report_Count;
1181	igmp_ifc_event(in_dev);
1182#endif
1183}
1184
1185
1186/*
1187 *	Multicast list managers
1188 */
1189
1190
1191/*
1192 *	A socket has joined a multicast group on device dev.
1193 */
1194
1195void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1196{
1197	struct ip_mc_list *im;
1198
1199	ASSERT_RTNL();
1200
1201	if (in_dev->dev->nd_net != &init_net)
1202		return;
1203
1204	for (im=in_dev->mc_list; im; im=im->next) {
1205		if (im->multiaddr == addr) {
1206			im->users++;
1207			ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1208			goto out;
1209		}
1210	}
1211
1212	im = kmalloc(sizeof(*im), GFP_KERNEL);
1213	if (!im)
1214		goto out;
1215
1216	im->users=1;
1217	im->interface=in_dev;
1218	in_dev_hold(in_dev);
1219	im->multiaddr=addr;
1220	/* initial mode is (EX, empty) */
1221	im->sfmode = MCAST_EXCLUDE;
1222	im->sfcount[MCAST_INCLUDE] = 0;
1223	im->sfcount[MCAST_EXCLUDE] = 1;
1224	im->sources = NULL;
1225	im->tomb = NULL;
1226	im->crcount = 0;
1227	atomic_set(&im->refcnt, 1);
1228	spin_lock_init(&im->lock);
1229#ifdef CONFIG_IP_MULTICAST
1230	im->tm_running=0;
1231	setup_timer(&im->timer, &igmp_timer_expire, (unsigned long)im);
1232	im->unsolicit_count = IGMP_Unsolicited_Report_Count;
1233	im->reporter = 0;
1234	im->gsquery = 0;
1235#endif
1236	im->loaded = 0;
1237	write_lock_bh(&in_dev->mc_list_lock);
1238	im->next=in_dev->mc_list;
1239	in_dev->mc_list=im;
1240	write_unlock_bh(&in_dev->mc_list_lock);
1241#ifdef CONFIG_IP_MULTICAST
1242	igmpv3_del_delrec(in_dev, im->multiaddr);
1243#endif
1244	igmp_group_added(im);
1245	if (!in_dev->dead)
1246		ip_rt_multicast_event(in_dev);
1247out:
1248	return;
1249}
1250
1251/*
1252 *	Resend IGMP JOIN report; used for bonding.
1253 */
1254void ip_mc_rejoin_group(struct ip_mc_list *im)
1255{
1256#ifdef CONFIG_IP_MULTICAST
1257	struct in_device *in_dev = im->interface;
1258
1259	if (im->multiaddr == IGMP_ALL_HOSTS)
1260		return;
1261
1262	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1263		igmp_mod_timer(im, IGMP_Initial_Report_Delay);
1264		return;
1265	}
1266	/* else, v3 */
1267	im->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1268		IGMP_Unsolicited_Report_Count;
1269	igmp_ifc_event(in_dev);
1270#endif
1271}
1272
1273/*
1274 *	A socket has left a multicast group on device dev
1275 */
1276
1277void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
1278{
1279	struct ip_mc_list *i, **ip;
1280
1281	ASSERT_RTNL();
1282
1283	if (in_dev->dev->nd_net != &init_net)
1284		return;
1285
1286	for (ip=&in_dev->mc_list; (i=*ip)!=NULL; ip=&i->next) {
1287		if (i->multiaddr==addr) {
1288			if (--i->users == 0) {
1289				write_lock_bh(&in_dev->mc_list_lock);
1290				*ip = i->next;
1291				write_unlock_bh(&in_dev->mc_list_lock);
1292				igmp_group_dropped(i);
1293
1294				if (!in_dev->dead)
1295					ip_rt_multicast_event(in_dev);
1296
1297				ip_ma_put(i);
1298				return;
1299			}
1300			break;
1301		}
1302	}
1303}
1304
1305/* Device going down */
1306
1307void ip_mc_down(struct in_device *in_dev)
1308{
1309	struct ip_mc_list *i;
1310
1311	ASSERT_RTNL();
1312
1313	if (in_dev->dev->nd_net != &init_net)
1314		return;
1315
1316	for (i=in_dev->mc_list; i; i=i->next)
1317		igmp_group_dropped(i);
1318
1319#ifdef CONFIG_IP_MULTICAST
1320	in_dev->mr_ifc_count = 0;
1321	if (del_timer(&in_dev->mr_ifc_timer))
1322		__in_dev_put(in_dev);
1323	in_dev->mr_gq_running = 0;
1324	if (del_timer(&in_dev->mr_gq_timer))
1325		__in_dev_put(in_dev);
1326	igmpv3_clear_delrec(in_dev);
1327#endif
1328
1329	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1330}
1331
1332void ip_mc_init_dev(struct in_device *in_dev)
1333{
1334	ASSERT_RTNL();
1335
1336	if (in_dev->dev->nd_net != &init_net)
1337		return;
1338
1339	in_dev->mc_tomb = NULL;
1340#ifdef CONFIG_IP_MULTICAST
1341	in_dev->mr_gq_running = 0;
1342	setup_timer(&in_dev->mr_gq_timer, igmp_gq_timer_expire,
1343			(unsigned long)in_dev);
1344	in_dev->mr_ifc_count = 0;
1345	setup_timer(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire,
1346			(unsigned long)in_dev);
1347	in_dev->mr_qrv = IGMP_Unsolicited_Report_Count;
1348#endif
1349
1350	rwlock_init(&in_dev->mc_list_lock);
1351	spin_lock_init(&in_dev->mc_tomb_lock);
1352}
1353
1354/* Device going up */
1355
1356void ip_mc_up(struct in_device *in_dev)
1357{
1358	struct ip_mc_list *i;
1359
1360	ASSERT_RTNL();
1361
1362	if (in_dev->dev->nd_net != &init_net)
1363		return;
1364
1365	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1366
1367	for (i=in_dev->mc_list; i; i=i->next)
1368		igmp_group_added(i);
1369}
1370
1371/*
1372 *	Device is about to be destroyed: clean up.
1373 */
1374
1375void ip_mc_destroy_dev(struct in_device *in_dev)
1376{
1377	struct ip_mc_list *i;
1378
1379	ASSERT_RTNL();
1380
1381	if (in_dev->dev->nd_net != &init_net)
1382		return;
1383
1384	/* Deactivate timers */
1385	ip_mc_down(in_dev);
1386
1387	write_lock_bh(&in_dev->mc_list_lock);
1388	while ((i = in_dev->mc_list) != NULL) {
1389		in_dev->mc_list = i->next;
1390		write_unlock_bh(&in_dev->mc_list_lock);
1391
1392		igmp_group_dropped(i);
1393		ip_ma_put(i);
1394
1395		write_lock_bh(&in_dev->mc_list_lock);
1396	}
1397	write_unlock_bh(&in_dev->mc_list_lock);
1398}
1399
1400static struct in_device * ip_mc_find_dev(struct ip_mreqn *imr)
1401{
1402	struct flowi fl = { .nl_u = { .ip4_u =
1403				      { .daddr = imr->imr_multiaddr.s_addr } } };
1404	struct rtable *rt;
1405	struct net_device *dev = NULL;
1406	struct in_device *idev = NULL;
1407
1408	if (imr->imr_ifindex) {
1409		idev = inetdev_by_index(&init_net, imr->imr_ifindex);
1410		if (idev)
1411			__in_dev_put(idev);
1412		return idev;
1413	}
1414	if (imr->imr_address.s_addr) {
1415		dev = ip_dev_find(&init_net, imr->imr_address.s_addr);
1416		if (!dev)
1417			return NULL;
1418		dev_put(dev);
1419	}
1420
1421	if (!dev && !ip_route_output_key(&init_net, &rt, &fl)) {
1422		dev = rt->u.dst.dev;
1423		ip_rt_put(rt);
1424	}
1425	if (dev) {
1426		imr->imr_ifindex = dev->ifindex;
1427		idev = __in_dev_get_rtnl(dev);
1428	}
1429	return idev;
1430}
1431
1432/*
1433 *	Join a socket to a group
1434 */
1435int sysctl_igmp_max_memberships __read_mostly = IP_MAX_MEMBERSHIPS;
1436int sysctl_igmp_max_msf __read_mostly = IP_MAX_MSF;
1437
1438
1439static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1440	__be32 *psfsrc)
1441{
1442	struct ip_sf_list *psf, *psf_prev;
1443	int rv = 0;
1444
1445	psf_prev = NULL;
1446	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1447		if (psf->sf_inaddr == *psfsrc)
1448			break;
1449		psf_prev = psf;
1450	}
1451	if (!psf || psf->sf_count[sfmode] == 0) {
1452		/* source filter not found, or count wrong =>  bug */
1453		return -ESRCH;
1454	}
1455	psf->sf_count[sfmode]--;
1456	if (psf->sf_count[sfmode] == 0) {
1457		ip_rt_multicast_event(pmc->interface);
1458	}
1459	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1460#ifdef CONFIG_IP_MULTICAST
1461		struct in_device *in_dev = pmc->interface;
1462#endif
1463
1464		/* no more filters for this source */
1465		if (psf_prev)
1466			psf_prev->sf_next = psf->sf_next;
1467		else
1468			pmc->sources = psf->sf_next;
1469#ifdef CONFIG_IP_MULTICAST
1470		if (psf->sf_oldin &&
1471		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1472			psf->sf_crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1473				IGMP_Unsolicited_Report_Count;
1474			psf->sf_next = pmc->tomb;
1475			pmc->tomb = psf;
1476			rv = 1;
1477		} else
1478#endif
1479			kfree(psf);
1480	}
1481	return rv;
1482}
1483
1484#ifndef CONFIG_IP_MULTICAST
1485#define igmp_ifc_event(x)	do { } while (0)
1486#endif
1487
1488static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1489			 int sfcount, __be32 *psfsrc, int delta)
1490{
1491	struct ip_mc_list *pmc;
1492	int	changerec = 0;
1493	int	i, err;
1494
1495	if (!in_dev)
1496		return -ENODEV;
1497	read_lock(&in_dev->mc_list_lock);
1498	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1499		if (*pmca == pmc->multiaddr)
1500			break;
1501	}
1502	if (!pmc) {
1503		/* MCA not found?? bug */
1504		read_unlock(&in_dev->mc_list_lock);
1505		return -ESRCH;
1506	}
1507	spin_lock_bh(&pmc->lock);
1508	read_unlock(&in_dev->mc_list_lock);
1509#ifdef CONFIG_IP_MULTICAST
1510	sf_markstate(pmc);
1511#endif
1512	if (!delta) {
1513		err = -EINVAL;
1514		if (!pmc->sfcount[sfmode])
1515			goto out_unlock;
1516		pmc->sfcount[sfmode]--;
1517	}
1518	err = 0;
1519	for (i=0; i<sfcount; i++) {
1520		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1521
1522		changerec |= rv > 0;
1523		if (!err && rv < 0)
1524			err = rv;
1525	}
1526	if (pmc->sfmode == MCAST_EXCLUDE &&
1527	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1528	    pmc->sfcount[MCAST_INCLUDE]) {
1529#ifdef CONFIG_IP_MULTICAST
1530		struct ip_sf_list *psf;
1531#endif
1532
1533		/* filter mode change */
1534		pmc->sfmode = MCAST_INCLUDE;
1535#ifdef CONFIG_IP_MULTICAST
1536		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1537			IGMP_Unsolicited_Report_Count;
1538		in_dev->mr_ifc_count = pmc->crcount;
1539		for (psf=pmc->sources; psf; psf = psf->sf_next)
1540			psf->sf_crcount = 0;
1541		igmp_ifc_event(pmc->interface);
1542	} else if (sf_setstate(pmc) || changerec) {
1543		igmp_ifc_event(pmc->interface);
1544#endif
1545	}
1546out_unlock:
1547	spin_unlock_bh(&pmc->lock);
1548	return err;
1549}
1550
1551/*
1552 * Add multicast single-source filter to the interface list
1553 */
1554static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1555	__be32 *psfsrc, int delta)
1556{
1557	struct ip_sf_list *psf, *psf_prev;
1558
1559	psf_prev = NULL;
1560	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1561		if (psf->sf_inaddr == *psfsrc)
1562			break;
1563		psf_prev = psf;
1564	}
1565	if (!psf) {
1566		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1567		if (!psf)
1568			return -ENOBUFS;
1569		psf->sf_inaddr = *psfsrc;
1570		if (psf_prev) {
1571			psf_prev->sf_next = psf;
1572		} else
1573			pmc->sources = psf;
1574	}
1575	psf->sf_count[sfmode]++;
1576	if (psf->sf_count[sfmode] == 1) {
1577		ip_rt_multicast_event(pmc->interface);
1578	}
1579	return 0;
1580}
1581
1582#ifdef CONFIG_IP_MULTICAST
1583static void sf_markstate(struct ip_mc_list *pmc)
1584{
1585	struct ip_sf_list *psf;
1586	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1587
1588	for (psf=pmc->sources; psf; psf=psf->sf_next)
1589		if (pmc->sfcount[MCAST_EXCLUDE]) {
1590			psf->sf_oldin = mca_xcount ==
1591				psf->sf_count[MCAST_EXCLUDE] &&
1592				!psf->sf_count[MCAST_INCLUDE];
1593		} else
1594			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1595}
1596
1597static int sf_setstate(struct ip_mc_list *pmc)
1598{
1599	struct ip_sf_list *psf, *dpsf;
1600	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1601	int qrv = pmc->interface->mr_qrv;
1602	int new_in, rv;
1603
1604	rv = 0;
1605	for (psf=pmc->sources; psf; psf=psf->sf_next) {
1606		if (pmc->sfcount[MCAST_EXCLUDE]) {
1607			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1608				!psf->sf_count[MCAST_INCLUDE];
1609		} else
1610			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1611		if (new_in) {
1612			if (!psf->sf_oldin) {
1613				struct ip_sf_list *prev = NULL;
1614
1615				for (dpsf=pmc->tomb; dpsf; dpsf=dpsf->sf_next) {
1616					if (dpsf->sf_inaddr == psf->sf_inaddr)
1617						break;
1618					prev = dpsf;
1619				}
1620				if (dpsf) {
1621					if (prev)
1622						prev->sf_next = dpsf->sf_next;
1623					else
1624						pmc->tomb = dpsf->sf_next;
1625					kfree(dpsf);
1626				}
1627				psf->sf_crcount = qrv;
1628				rv++;
1629			}
1630		} else if (psf->sf_oldin) {
1631
1632			psf->sf_crcount = 0;
1633			/*
1634			 * add or update "delete" records if an active filter
1635			 * is now inactive
1636			 */
1637			for (dpsf=pmc->tomb; dpsf; dpsf=dpsf->sf_next)
1638				if (dpsf->sf_inaddr == psf->sf_inaddr)
1639					break;
1640			if (!dpsf) {
1641				dpsf = (struct ip_sf_list *)
1642					kmalloc(sizeof(*dpsf), GFP_ATOMIC);
1643				if (!dpsf)
1644					continue;
1645				*dpsf = *psf;
1646				/* pmc->lock held by callers */
1647				dpsf->sf_next = pmc->tomb;
1648				pmc->tomb = dpsf;
1649			}
1650			dpsf->sf_crcount = qrv;
1651			rv++;
1652		}
1653	}
1654	return rv;
1655}
1656#endif
1657
1658/*
1659 * Add multicast source filter list to the interface list
1660 */
1661static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1662			 int sfcount, __be32 *psfsrc, int delta)
1663{
1664	struct ip_mc_list *pmc;
1665	int	isexclude;
1666	int	i, err;
1667
1668	if (!in_dev)
1669		return -ENODEV;
1670	read_lock(&in_dev->mc_list_lock);
1671	for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1672		if (*pmca == pmc->multiaddr)
1673			break;
1674	}
1675	if (!pmc) {
1676		/* MCA not found?? bug */
1677		read_unlock(&in_dev->mc_list_lock);
1678		return -ESRCH;
1679	}
1680	spin_lock_bh(&pmc->lock);
1681	read_unlock(&in_dev->mc_list_lock);
1682
1683#ifdef CONFIG_IP_MULTICAST
1684	sf_markstate(pmc);
1685#endif
1686	isexclude = pmc->sfmode == MCAST_EXCLUDE;
1687	if (!delta)
1688		pmc->sfcount[sfmode]++;
1689	err = 0;
1690	for (i=0; i<sfcount; i++) {
1691		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i], delta);
1692		if (err)
1693			break;
1694	}
1695	if (err) {
1696		int j;
1697
1698		pmc->sfcount[sfmode]--;
1699		for (j=0; j<i; j++)
1700			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1701	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
1702#ifdef CONFIG_IP_MULTICAST
1703		struct ip_sf_list *psf;
1704		in_dev = pmc->interface;
1705#endif
1706
1707		/* filter mode change */
1708		if (pmc->sfcount[MCAST_EXCLUDE])
1709			pmc->sfmode = MCAST_EXCLUDE;
1710		else if (pmc->sfcount[MCAST_INCLUDE])
1711			pmc->sfmode = MCAST_INCLUDE;
1712#ifdef CONFIG_IP_MULTICAST
1713		/* else no filters; keep old mode for reports */
1714
1715		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1716			IGMP_Unsolicited_Report_Count;
1717		in_dev->mr_ifc_count = pmc->crcount;
1718		for (psf=pmc->sources; psf; psf = psf->sf_next)
1719			psf->sf_crcount = 0;
1720		igmp_ifc_event(in_dev);
1721	} else if (sf_setstate(pmc)) {
1722		igmp_ifc_event(in_dev);
1723#endif
1724	}
1725	spin_unlock_bh(&pmc->lock);
1726	return err;
1727}
1728
1729static void ip_mc_clear_src(struct ip_mc_list *pmc)
1730{
1731	struct ip_sf_list *psf, *nextpsf;
1732
1733	for (psf=pmc->tomb; psf; psf=nextpsf) {
1734		nextpsf = psf->sf_next;
1735		kfree(psf);
1736	}
1737	pmc->tomb = NULL;
1738	for (psf=pmc->sources; psf; psf=nextpsf) {
1739		nextpsf = psf->sf_next;
1740		kfree(psf);
1741	}
1742	pmc->sources = NULL;
1743	pmc->sfmode = MCAST_EXCLUDE;
1744	pmc->sfcount[MCAST_INCLUDE] = 0;
1745	pmc->sfcount[MCAST_EXCLUDE] = 1;
1746}
1747
1748
1749/*
1750 * Join a multicast group
1751 */
1752int ip_mc_join_group(struct sock *sk , struct ip_mreqn *imr)
1753{
1754	int err;
1755	__be32 addr = imr->imr_multiaddr.s_addr;
1756	struct ip_mc_socklist *iml=NULL, *i;
1757	struct in_device *in_dev;
1758	struct inet_sock *inet = inet_sk(sk);
1759	int ifindex;
1760	int count = 0;
1761
1762	if (!ipv4_is_multicast(addr))
1763		return -EINVAL;
1764
1765	if (sk->sk_net != &init_net)
1766		return -EPROTONOSUPPORT;
1767
1768	rtnl_lock();
1769
1770	in_dev = ip_mc_find_dev(imr);
1771
1772	if (!in_dev) {
1773		iml = NULL;
1774		err = -ENODEV;
1775		goto done;
1776	}
1777
1778	err = -EADDRINUSE;
1779	ifindex = imr->imr_ifindex;
1780	for (i = inet->mc_list; i; i = i->next) {
1781		if (i->multi.imr_multiaddr.s_addr == addr &&
1782		    i->multi.imr_ifindex == ifindex)
1783			goto done;
1784		count++;
1785	}
1786	err = -ENOBUFS;
1787	if (count >= sysctl_igmp_max_memberships)
1788		goto done;
1789	iml = sock_kmalloc(sk,sizeof(*iml),GFP_KERNEL);
1790	if (iml == NULL)
1791		goto done;
1792
1793	memcpy(&iml->multi, imr, sizeof(*imr));
1794	iml->next = inet->mc_list;
1795	iml->sflist = NULL;
1796	iml->sfmode = MCAST_EXCLUDE;
1797	inet->mc_list = iml;
1798	ip_mc_inc_group(in_dev, addr);
1799	err = 0;
1800done:
1801	rtnl_unlock();
1802	return err;
1803}
1804
1805static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
1806			   struct in_device *in_dev)
1807{
1808	int err;
1809
1810	if (iml->sflist == NULL) {
1811		/* any-source empty exclude case */
1812		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1813			iml->sfmode, 0, NULL, 0);
1814	}
1815	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1816			iml->sfmode, iml->sflist->sl_count,
1817			iml->sflist->sl_addr, 0);
1818	sock_kfree_s(sk, iml->sflist, IP_SFLSIZE(iml->sflist->sl_max));
1819	iml->sflist = NULL;
1820	return err;
1821}
1822
1823/*
1824 *	Ask a socket to leave a group.
1825 */
1826
1827int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
1828{
1829	struct inet_sock *inet = inet_sk(sk);
1830	struct ip_mc_socklist *iml, **imlp;
1831	struct in_device *in_dev;
1832	__be32 group = imr->imr_multiaddr.s_addr;
1833	u32 ifindex;
1834	int ret = -EADDRNOTAVAIL;
1835
1836	if (sk->sk_net != &init_net)
1837		return -EPROTONOSUPPORT;
1838
1839	rtnl_lock();
1840	in_dev = ip_mc_find_dev(imr);
1841	ifindex = imr->imr_ifindex;
1842	for (imlp = &inet->mc_list; (iml = *imlp) != NULL; imlp = &iml->next) {
1843		if (iml->multi.imr_multiaddr.s_addr != group)
1844			continue;
1845		if (ifindex) {
1846			if (iml->multi.imr_ifindex != ifindex)
1847				continue;
1848		} else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
1849				iml->multi.imr_address.s_addr)
1850			continue;
1851
1852		(void) ip_mc_leave_src(sk, iml, in_dev);
1853
1854		*imlp = iml->next;
1855
1856		if (in_dev)
1857			ip_mc_dec_group(in_dev, group);
1858		rtnl_unlock();
1859		sock_kfree_s(sk, iml, sizeof(*iml));
1860		return 0;
1861	}
1862	if (!in_dev)
1863		ret = -ENODEV;
1864	rtnl_unlock();
1865	return ret;
1866}
1867
1868int ip_mc_source(int add, int omode, struct sock *sk, struct
1869	ip_mreq_source *mreqs, int ifindex)
1870{
1871	int err;
1872	struct ip_mreqn imr;
1873	__be32 addr = mreqs->imr_multiaddr;
1874	struct ip_mc_socklist *pmc;
1875	struct in_device *in_dev = NULL;
1876	struct inet_sock *inet = inet_sk(sk);
1877	struct ip_sf_socklist *psl;
1878	int leavegroup = 0;
1879	int i, j, rv;
1880
1881	if (!ipv4_is_multicast(addr))
1882		return -EINVAL;
1883
1884	if (sk->sk_net != &init_net)
1885		return -EPROTONOSUPPORT;
1886
1887	rtnl_lock();
1888
1889	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
1890	imr.imr_address.s_addr = mreqs->imr_interface;
1891	imr.imr_ifindex = ifindex;
1892	in_dev = ip_mc_find_dev(&imr);
1893
1894	if (!in_dev) {
1895		err = -ENODEV;
1896		goto done;
1897	}
1898	err = -EADDRNOTAVAIL;
1899
1900	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
1901		if (pmc->multi.imr_multiaddr.s_addr == imr.imr_multiaddr.s_addr
1902		    && pmc->multi.imr_ifindex == imr.imr_ifindex)
1903			break;
1904	}
1905	if (!pmc) {		/* must have a prior join */
1906		err = -EINVAL;
1907		goto done;
1908	}
1909	/* if a source filter was set, must be the same mode as before */
1910	if (pmc->sflist) {
1911		if (pmc->sfmode != omode) {
1912			err = -EINVAL;
1913			goto done;
1914		}
1915	} else if (pmc->sfmode != omode) {
1916		/* allow mode switches for empty-set filters */
1917		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
1918		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
1919			NULL, 0);
1920		pmc->sfmode = omode;
1921	}
1922
1923	psl = pmc->sflist;
1924	if (!add) {
1925		if (!psl)
1926			goto done;	/* err = -EADDRNOTAVAIL */
1927		rv = !0;
1928		for (i=0; i<psl->sl_count; i++) {
1929			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1930				sizeof(__be32));
1931			if (rv == 0)
1932				break;
1933		}
1934		if (rv)		/* source not found */
1935			goto done;	/* err = -EADDRNOTAVAIL */
1936
1937		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
1938		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
1939			leavegroup = 1;
1940			goto done;
1941		}
1942
1943		/* update the interface filter */
1944		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1945			&mreqs->imr_sourceaddr, 1);
1946
1947		for (j=i+1; j<psl->sl_count; j++)
1948			psl->sl_addr[j-1] = psl->sl_addr[j];
1949		psl->sl_count--;
1950		err = 0;
1951		goto done;
1952	}
1953	/* else, add a new source to the filter */
1954
1955	if (psl && psl->sl_count >= sysctl_igmp_max_msf) {
1956		err = -ENOBUFS;
1957		goto done;
1958	}
1959	if (!psl || psl->sl_count == psl->sl_max) {
1960		struct ip_sf_socklist *newpsl;
1961		int count = IP_SFBLOCK;
1962
1963		if (psl)
1964			count += psl->sl_max;
1965		newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
1966		if (!newpsl) {
1967			err = -ENOBUFS;
1968			goto done;
1969		}
1970		newpsl->sl_max = count;
1971		newpsl->sl_count = count - IP_SFBLOCK;
1972		if (psl) {
1973			for (i=0; i<psl->sl_count; i++)
1974				newpsl->sl_addr[i] = psl->sl_addr[i];
1975			sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
1976		}
1977		pmc->sflist = psl = newpsl;
1978	}
1979	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
1980	for (i=0; i<psl->sl_count; i++) {
1981		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1982			sizeof(__be32));
1983		if (rv == 0)
1984			break;
1985	}
1986	if (rv == 0)		/* address already there is an error */
1987		goto done;
1988	for (j=psl->sl_count-1; j>=i; j--)
1989		psl->sl_addr[j+1] = psl->sl_addr[j];
1990	psl->sl_addr[i] = mreqs->imr_sourceaddr;
1991	psl->sl_count++;
1992	err = 0;
1993	/* update the interface list */
1994	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1995		&mreqs->imr_sourceaddr, 1);
1996done:
1997	rtnl_unlock();
1998	if (leavegroup)
1999		return ip_mc_leave_group(sk, &imr);
2000	return err;
2001}
2002
2003int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2004{
2005	int err = 0;
2006	struct ip_mreqn	imr;
2007	__be32 addr = msf->imsf_multiaddr;
2008	struct ip_mc_socklist *pmc;
2009	struct in_device *in_dev;
2010	struct inet_sock *inet = inet_sk(sk);
2011	struct ip_sf_socklist *newpsl, *psl;
2012	int leavegroup = 0;
2013
2014	if (!ipv4_is_multicast(addr))
2015		return -EINVAL;
2016	if (msf->imsf_fmode != MCAST_INCLUDE &&
2017	    msf->imsf_fmode != MCAST_EXCLUDE)
2018		return -EINVAL;
2019
2020	if (sk->sk_net != &init_net)
2021		return -EPROTONOSUPPORT;
2022
2023	rtnl_lock();
2024
2025	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2026	imr.imr_address.s_addr = msf->imsf_interface;
2027	imr.imr_ifindex = ifindex;
2028	in_dev = ip_mc_find_dev(&imr);
2029
2030	if (!in_dev) {
2031		err = -ENODEV;
2032		goto done;
2033	}
2034
2035	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2036	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2037		leavegroup = 1;
2038		goto done;
2039	}
2040
2041	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2042		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2043		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2044			break;
2045	}
2046	if (!pmc) {		/* must have a prior join */
2047		err = -EINVAL;
2048		goto done;
2049	}
2050	if (msf->imsf_numsrc) {
2051		newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2052							   GFP_KERNEL);
2053		if (!newpsl) {
2054			err = -ENOBUFS;
2055			goto done;
2056		}
2057		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2058		memcpy(newpsl->sl_addr, msf->imsf_slist,
2059			msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2060		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2061			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2062		if (err) {
2063			sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2064			goto done;
2065		}
2066	} else {
2067		newpsl = NULL;
2068		(void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2069				     msf->imsf_fmode, 0, NULL, 0);
2070	}
2071	psl = pmc->sflist;
2072	if (psl) {
2073		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2074			psl->sl_count, psl->sl_addr, 0);
2075		sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
2076	} else
2077		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2078			0, NULL, 0);
2079	pmc->sflist = newpsl;
2080	pmc->sfmode = msf->imsf_fmode;
2081	err = 0;
2082done:
2083	rtnl_unlock();
2084	if (leavegroup)
2085		err = ip_mc_leave_group(sk, &imr);
2086	return err;
2087}
2088
2089int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2090	struct ip_msfilter __user *optval, int __user *optlen)
2091{
2092	int err, len, count, copycount;
2093	struct ip_mreqn	imr;
2094	__be32 addr = msf->imsf_multiaddr;
2095	struct ip_mc_socklist *pmc;
2096	struct in_device *in_dev;
2097	struct inet_sock *inet = inet_sk(sk);
2098	struct ip_sf_socklist *psl;
2099
2100	if (!ipv4_is_multicast(addr))
2101		return -EINVAL;
2102
2103	if (sk->sk_net != &init_net)
2104		return -EPROTONOSUPPORT;
2105
2106	rtnl_lock();
2107
2108	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2109	imr.imr_address.s_addr = msf->imsf_interface;
2110	imr.imr_ifindex = 0;
2111	in_dev = ip_mc_find_dev(&imr);
2112
2113	if (!in_dev) {
2114		err = -ENODEV;
2115		goto done;
2116	}
2117	err = -EADDRNOTAVAIL;
2118
2119	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2120		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2121		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2122			break;
2123	}
2124	if (!pmc)		/* must have a prior join */
2125		goto done;
2126	msf->imsf_fmode = pmc->sfmode;
2127	psl = pmc->sflist;
2128	rtnl_unlock();
2129	if (!psl) {
2130		len = 0;
2131		count = 0;
2132	} else {
2133		count = psl->sl_count;
2134	}
2135	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2136	len = copycount * sizeof(psl->sl_addr[0]);
2137	msf->imsf_numsrc = count;
2138	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2139	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2140		return -EFAULT;
2141	}
2142	if (len &&
2143	    copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2144		return -EFAULT;
2145	return 0;
2146done:
2147	rtnl_unlock();
2148	return err;
2149}
2150
2151int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2152	struct group_filter __user *optval, int __user *optlen)
2153{
2154	int err, i, count, copycount;
2155	struct sockaddr_in *psin;
2156	__be32 addr;
2157	struct ip_mc_socklist *pmc;
2158	struct inet_sock *inet = inet_sk(sk);
2159	struct ip_sf_socklist *psl;
2160
2161	psin = (struct sockaddr_in *)&gsf->gf_group;
2162	if (psin->sin_family != AF_INET)
2163		return -EINVAL;
2164	addr = psin->sin_addr.s_addr;
2165	if (!ipv4_is_multicast(addr))
2166		return -EINVAL;
2167
2168	if (sk->sk_net != &init_net)
2169		return -EPROTONOSUPPORT;
2170
2171	rtnl_lock();
2172
2173	err = -EADDRNOTAVAIL;
2174
2175	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2176		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2177		    pmc->multi.imr_ifindex == gsf->gf_interface)
2178			break;
2179	}
2180	if (!pmc)		/* must have a prior join */
2181		goto done;
2182	gsf->gf_fmode = pmc->sfmode;
2183	psl = pmc->sflist;
2184	rtnl_unlock();
2185	count = psl ? psl->sl_count : 0;
2186	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2187	gsf->gf_numsrc = count;
2188	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2189	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2190		return -EFAULT;
2191	}
2192	for (i=0; i<copycount; i++) {
2193		struct sockaddr_storage ss;
2194
2195		psin = (struct sockaddr_in *)&ss;
2196		memset(&ss, 0, sizeof(ss));
2197		psin->sin_family = AF_INET;
2198		psin->sin_addr.s_addr = psl->sl_addr[i];
2199		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2200			return -EFAULT;
2201	}
2202	return 0;
2203done:
2204	rtnl_unlock();
2205	return err;
2206}
2207
2208/*
2209 * check if a multicast source filter allows delivery for a given <src,dst,intf>
2210 */
2211int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif)
2212{
2213	struct inet_sock *inet = inet_sk(sk);
2214	struct ip_mc_socklist *pmc;
2215	struct ip_sf_socklist *psl;
2216	int i;
2217
2218	if (!ipv4_is_multicast(loc_addr))
2219		return 1;
2220
2221	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2222		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2223		    pmc->multi.imr_ifindex == dif)
2224			break;
2225	}
2226	if (!pmc)
2227		return 1;
2228	psl = pmc->sflist;
2229	if (!psl)
2230		return pmc->sfmode == MCAST_EXCLUDE;
2231
2232	for (i=0; i<psl->sl_count; i++) {
2233		if (psl->sl_addr[i] == rmt_addr)
2234			break;
2235	}
2236	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2237		return 0;
2238	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2239		return 0;
2240	return 1;
2241}
2242
2243/*
2244 *	A socket is closing.
2245 */
2246
2247void ip_mc_drop_socket(struct sock *sk)
2248{
2249	struct inet_sock *inet = inet_sk(sk);
2250	struct ip_mc_socklist *iml;
2251
2252	if (inet->mc_list == NULL)
2253		return;
2254
2255	if (sk->sk_net != &init_net)
2256		return;
2257
2258	rtnl_lock();
2259	while ((iml = inet->mc_list) != NULL) {
2260		struct in_device *in_dev;
2261		inet->mc_list = iml->next;
2262
2263		in_dev = inetdev_by_index(&init_net, iml->multi.imr_ifindex);
2264		(void) ip_mc_leave_src(sk, iml, in_dev);
2265		if (in_dev != NULL) {
2266			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2267			in_dev_put(in_dev);
2268		}
2269		sock_kfree_s(sk, iml, sizeof(*iml));
2270	}
2271	rtnl_unlock();
2272}
2273
2274int ip_check_mc(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u16 proto)
2275{
2276	struct ip_mc_list *im;
2277	struct ip_sf_list *psf;
2278	int rv = 0;
2279
2280	read_lock(&in_dev->mc_list_lock);
2281	for (im=in_dev->mc_list; im; im=im->next) {
2282		if (im->multiaddr == mc_addr)
2283			break;
2284	}
2285	if (im && proto == IPPROTO_IGMP) {
2286		rv = 1;
2287	} else if (im) {
2288		if (src_addr) {
2289			for (psf=im->sources; psf; psf=psf->sf_next) {
2290				if (psf->sf_inaddr == src_addr)
2291					break;
2292			}
2293			if (psf)
2294				rv = psf->sf_count[MCAST_INCLUDE] ||
2295					psf->sf_count[MCAST_EXCLUDE] !=
2296					im->sfcount[MCAST_EXCLUDE];
2297			else
2298				rv = im->sfcount[MCAST_EXCLUDE] != 0;
2299		} else
2300			rv = 1; /* unspecified source; tentatively allow */
2301	}
2302	read_unlock(&in_dev->mc_list_lock);
2303	return rv;
2304}
2305
2306#if defined(CONFIG_PROC_FS)
2307struct igmp_mc_iter_state {
2308	struct net_device *dev;
2309	struct in_device *in_dev;
2310};
2311
2312#define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2313
2314static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2315{
2316	struct ip_mc_list *im = NULL;
2317	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2318
2319	state->in_dev = NULL;
2320	for_each_netdev(&init_net, state->dev) {
2321		struct in_device *in_dev;
2322		in_dev = in_dev_get(state->dev);
2323		if (!in_dev)
2324			continue;
2325		read_lock(&in_dev->mc_list_lock);
2326		im = in_dev->mc_list;
2327		if (im) {
2328			state->in_dev = in_dev;
2329			break;
2330		}
2331		read_unlock(&in_dev->mc_list_lock);
2332		in_dev_put(in_dev);
2333	}
2334	return im;
2335}
2336
2337static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2338{
2339	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2340	im = im->next;
2341	while (!im) {
2342		if (likely(state->in_dev != NULL)) {
2343			read_unlock(&state->in_dev->mc_list_lock);
2344			in_dev_put(state->in_dev);
2345		}
2346		state->dev = next_net_device(state->dev);
2347		if (!state->dev) {
2348			state->in_dev = NULL;
2349			break;
2350		}
2351		state->in_dev = in_dev_get(state->dev);
2352		if (!state->in_dev)
2353			continue;
2354		read_lock(&state->in_dev->mc_list_lock);
2355		im = state->in_dev->mc_list;
2356	}
2357	return im;
2358}
2359
2360static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2361{
2362	struct ip_mc_list *im = igmp_mc_get_first(seq);
2363	if (im)
2364		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2365			--pos;
2366	return pos ? NULL : im;
2367}
2368
2369static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2370	__acquires(dev_base_lock)
2371{
2372	read_lock(&dev_base_lock);
2373	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2374}
2375
2376static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2377{
2378	struct ip_mc_list *im;
2379	if (v == SEQ_START_TOKEN)
2380		im = igmp_mc_get_first(seq);
2381	else
2382		im = igmp_mc_get_next(seq, v);
2383	++*pos;
2384	return im;
2385}
2386
2387static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2388	__releases(dev_base_lock)
2389{
2390	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2391	if (likely(state->in_dev != NULL)) {
2392		read_unlock(&state->in_dev->mc_list_lock);
2393		in_dev_put(state->in_dev);
2394		state->in_dev = NULL;
2395	}
2396	state->dev = NULL;
2397	read_unlock(&dev_base_lock);
2398}
2399
2400static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2401{
2402	if (v == SEQ_START_TOKEN)
2403		seq_puts(seq,
2404			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2405	else {
2406		struct ip_mc_list *im = (struct ip_mc_list *)v;
2407		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2408		char   *querier;
2409#ifdef CONFIG_IP_MULTICAST
2410		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2411			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2412			  "V3";
2413#else
2414		querier = "NONE";
2415#endif
2416
2417		if (state->in_dev->mc_list == im) {
2418			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2419				   state->dev->ifindex, state->dev->name, state->dev->mc_count, querier);
2420		}
2421
2422		seq_printf(seq,
2423			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2424			   im->multiaddr, im->users,
2425			   im->tm_running, im->tm_running ?
2426			   jiffies_to_clock_t(im->timer.expires-jiffies) : 0,
2427			   im->reporter);
2428	}
2429	return 0;
2430}
2431
2432static const struct seq_operations igmp_mc_seq_ops = {
2433	.start	=	igmp_mc_seq_start,
2434	.next	=	igmp_mc_seq_next,
2435	.stop	=	igmp_mc_seq_stop,
2436	.show	=	igmp_mc_seq_show,
2437};
2438
2439static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2440{
2441	return seq_open_private(file, &igmp_mc_seq_ops,
2442			sizeof(struct igmp_mc_iter_state));
2443}
2444
2445static const struct file_operations igmp_mc_seq_fops = {
2446	.owner		=	THIS_MODULE,
2447	.open		=	igmp_mc_seq_open,
2448	.read		=	seq_read,
2449	.llseek		=	seq_lseek,
2450	.release	=	seq_release_private,
2451};
2452
2453struct igmp_mcf_iter_state {
2454	struct net_device *dev;
2455	struct in_device *idev;
2456	struct ip_mc_list *im;
2457};
2458
2459#define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2460
2461static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2462{
2463	struct ip_sf_list *psf = NULL;
2464	struct ip_mc_list *im = NULL;
2465	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2466
2467	state->idev = NULL;
2468	state->im = NULL;
2469	for_each_netdev(&init_net, state->dev) {
2470		struct in_device *idev;
2471		idev = in_dev_get(state->dev);
2472		if (unlikely(idev == NULL))
2473			continue;
2474		read_lock(&idev->mc_list_lock);
2475		im = idev->mc_list;
2476		if (likely(im != NULL)) {
2477			spin_lock_bh(&im->lock);
2478			psf = im->sources;
2479			if (likely(psf != NULL)) {
2480				state->im = im;
2481				state->idev = idev;
2482				break;
2483			}
2484			spin_unlock_bh(&im->lock);
2485		}
2486		read_unlock(&idev->mc_list_lock);
2487		in_dev_put(idev);
2488	}
2489	return psf;
2490}
2491
2492static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2493{
2494	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2495
2496	psf = psf->sf_next;
2497	while (!psf) {
2498		spin_unlock_bh(&state->im->lock);
2499		state->im = state->im->next;
2500		while (!state->im) {
2501			if (likely(state->idev != NULL)) {
2502				read_unlock(&state->idev->mc_list_lock);
2503				in_dev_put(state->idev);
2504			}
2505			state->dev = next_net_device(state->dev);
2506			if (!state->dev) {
2507				state->idev = NULL;
2508				goto out;
2509			}
2510			state->idev = in_dev_get(state->dev);
2511			if (!state->idev)
2512				continue;
2513			read_lock(&state->idev->mc_list_lock);
2514			state->im = state->idev->mc_list;
2515		}
2516		if (!state->im)
2517			break;
2518		spin_lock_bh(&state->im->lock);
2519		psf = state->im->sources;
2520	}
2521out:
2522	return psf;
2523}
2524
2525static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2526{
2527	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2528	if (psf)
2529		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2530			--pos;
2531	return pos ? NULL : psf;
2532}
2533
2534static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2535{
2536	read_lock(&dev_base_lock);
2537	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2538}
2539
2540static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2541{
2542	struct ip_sf_list *psf;
2543	if (v == SEQ_START_TOKEN)
2544		psf = igmp_mcf_get_first(seq);
2545	else
2546		psf = igmp_mcf_get_next(seq, v);
2547	++*pos;
2548	return psf;
2549}
2550
2551static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2552{
2553	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2554	if (likely(state->im != NULL)) {
2555		spin_unlock_bh(&state->im->lock);
2556		state->im = NULL;
2557	}
2558	if (likely(state->idev != NULL)) {
2559		read_unlock(&state->idev->mc_list_lock);
2560		in_dev_put(state->idev);
2561		state->idev = NULL;
2562	}
2563	state->dev = NULL;
2564	read_unlock(&dev_base_lock);
2565}
2566
2567static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2568{
2569	struct ip_sf_list *psf = (struct ip_sf_list *)v;
2570	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2571
2572	if (v == SEQ_START_TOKEN) {
2573		seq_printf(seq,
2574			   "%3s %6s "
2575			   "%10s %10s %6s %6s\n", "Idx",
2576			   "Device", "MCA",
2577			   "SRC", "INC", "EXC");
2578	} else {
2579		seq_printf(seq,
2580			   "%3d %6.6s 0x%08x "
2581			   "0x%08x %6lu %6lu\n",
2582			   state->dev->ifindex, state->dev->name,
2583			   ntohl(state->im->multiaddr),
2584			   ntohl(psf->sf_inaddr),
2585			   psf->sf_count[MCAST_INCLUDE],
2586			   psf->sf_count[MCAST_EXCLUDE]);
2587	}
2588	return 0;
2589}
2590
2591static const struct seq_operations igmp_mcf_seq_ops = {
2592	.start	=	igmp_mcf_seq_start,
2593	.next	=	igmp_mcf_seq_next,
2594	.stop	=	igmp_mcf_seq_stop,
2595	.show	=	igmp_mcf_seq_show,
2596};
2597
2598static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2599{
2600	return seq_open_private(file, &igmp_mcf_seq_ops,
2601			sizeof(struct igmp_mcf_iter_state));
2602}
2603
2604static const struct file_operations igmp_mcf_seq_fops = {
2605	.owner		=	THIS_MODULE,
2606	.open		=	igmp_mcf_seq_open,
2607	.read		=	seq_read,
2608	.llseek		=	seq_lseek,
2609	.release	=	seq_release_private,
2610};
2611
2612int __init igmp_mc_proc_init(void)
2613{
2614	proc_net_fops_create(&init_net, "igmp", S_IRUGO, &igmp_mc_seq_fops);
2615	proc_net_fops_create(&init_net, "mcfilter", S_IRUGO, &igmp_mcf_seq_fops);
2616	return 0;
2617}
2618#endif
2619
2620EXPORT_SYMBOL(ip_mc_dec_group);
2621EXPORT_SYMBOL(ip_mc_inc_group);
2622EXPORT_SYMBOL(ip_mc_join_group);
2623EXPORT_SYMBOL(ip_mc_rejoin_group);
2624