igmp.c revision 179542a548f37e1366f7afb7a088c965a2adf7d0
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 <linux/types.h>
77#include <linux/kernel.h>
78#include <linux/jiffies.h>
79#include <linux/string.h>
80#include <linux/socket.h>
81#include <linux/sockios.h>
82#include <linux/in.h>
83#include <linux/inet.h>
84#include <linux/netdevice.h>
85#include <linux/skbuff.h>
86#include <linux/inetdevice.h>
87#include <linux/igmp.h>
88#include <linux/if_arp.h>
89#include <linux/rtnetlink.h>
90#include <linux/times.h>
91#include <linux/pkt_sched.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_V2_Unsolicited_Report_Interval	(10*HZ)
118#define IGMP_V3_Unsolicited_Report_Interval	(1*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(dev_net(in_dev->dev), 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(dev_net(in_dev->dev), 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 int unsolicited_report_interval(struct in_device *in_dev)
144{
145	int interval_ms, interval_jiffies;
146
147	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
148		interval_ms = IN_DEV_CONF_GET(
149			in_dev,
150			IGMPV2_UNSOLICITED_REPORT_INTERVAL);
151	else /* v3 */
152		interval_ms = IN_DEV_CONF_GET(
153			in_dev,
154			IGMPV3_UNSOLICITED_REPORT_INTERVAL);
155
156	interval_jiffies = msecs_to_jiffies(interval_ms);
157
158	/* _timer functions can't handle a delay of 0 jiffies so ensure
159	 *  we always return a positive value.
160	 */
161	if (interval_jiffies <= 0)
162		interval_jiffies = 1;
163	return interval_jiffies;
164}
165
166static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im);
167static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr);
168static void igmpv3_clear_delrec(struct in_device *in_dev);
169static int sf_setstate(struct ip_mc_list *pmc);
170static void sf_markstate(struct ip_mc_list *pmc);
171#endif
172static void ip_mc_clear_src(struct ip_mc_list *pmc);
173static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
174			 int sfcount, __be32 *psfsrc, int delta);
175
176static void ip_ma_put(struct ip_mc_list *im)
177{
178	if (atomic_dec_and_test(&im->refcnt)) {
179		in_dev_put(im->interface);
180		kfree_rcu(im, rcu);
181	}
182}
183
184#define for_each_pmc_rcu(in_dev, pmc)				\
185	for (pmc = rcu_dereference(in_dev->mc_list);		\
186	     pmc != NULL;					\
187	     pmc = rcu_dereference(pmc->next_rcu))
188
189#define for_each_pmc_rtnl(in_dev, pmc)				\
190	for (pmc = rtnl_dereference(in_dev->mc_list);		\
191	     pmc != NULL;					\
192	     pmc = rtnl_dereference(pmc->next_rcu))
193
194#ifdef CONFIG_IP_MULTICAST
195
196/*
197 *	Timer management
198 */
199
200static void igmp_stop_timer(struct ip_mc_list *im)
201{
202	spin_lock_bh(&im->lock);
203	if (del_timer(&im->timer))
204		atomic_dec(&im->refcnt);
205	im->tm_running = 0;
206	im->reporter = 0;
207	im->unsolicit_count = 0;
208	spin_unlock_bh(&im->lock);
209}
210
211/* It must be called with locked im->lock */
212static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
213{
214	int tv = prandom_u32() % max_delay;
215
216	im->tm_running = 1;
217	if (!mod_timer(&im->timer, jiffies+tv+2))
218		atomic_inc(&im->refcnt);
219}
220
221static void igmp_gq_start_timer(struct in_device *in_dev)
222{
223	int tv = prandom_u32() % in_dev->mr_maxdelay;
224
225	in_dev->mr_gq_running = 1;
226	if (!mod_timer(&in_dev->mr_gq_timer, jiffies+tv+2))
227		in_dev_hold(in_dev);
228}
229
230static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
231{
232	int tv = prandom_u32() % delay;
233
234	if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
235		in_dev_hold(in_dev);
236}
237
238static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
239{
240	spin_lock_bh(&im->lock);
241	im->unsolicit_count = 0;
242	if (del_timer(&im->timer)) {
243		if ((long)(im->timer.expires-jiffies) < max_delay) {
244			add_timer(&im->timer);
245			im->tm_running = 1;
246			spin_unlock_bh(&im->lock);
247			return;
248		}
249		atomic_dec(&im->refcnt);
250	}
251	igmp_start_timer(im, max_delay);
252	spin_unlock_bh(&im->lock);
253}
254
255
256/*
257 *	Send an IGMP report.
258 */
259
260#define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
261
262
263static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
264	int gdeleted, int sdeleted)
265{
266	switch (type) {
267	case IGMPV3_MODE_IS_INCLUDE:
268	case IGMPV3_MODE_IS_EXCLUDE:
269		if (gdeleted || sdeleted)
270			return 0;
271		if (!(pmc->gsquery && !psf->sf_gsresp)) {
272			if (pmc->sfmode == MCAST_INCLUDE)
273				return 1;
274			/* don't include if this source is excluded
275			 * in all filters
276			 */
277			if (psf->sf_count[MCAST_INCLUDE])
278				return type == IGMPV3_MODE_IS_INCLUDE;
279			return pmc->sfcount[MCAST_EXCLUDE] ==
280				psf->sf_count[MCAST_EXCLUDE];
281		}
282		return 0;
283	case IGMPV3_CHANGE_TO_INCLUDE:
284		if (gdeleted || sdeleted)
285			return 0;
286		return psf->sf_count[MCAST_INCLUDE] != 0;
287	case IGMPV3_CHANGE_TO_EXCLUDE:
288		if (gdeleted || sdeleted)
289			return 0;
290		if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
291		    psf->sf_count[MCAST_INCLUDE])
292			return 0;
293		return pmc->sfcount[MCAST_EXCLUDE] ==
294			psf->sf_count[MCAST_EXCLUDE];
295	case IGMPV3_ALLOW_NEW_SOURCES:
296		if (gdeleted || !psf->sf_crcount)
297			return 0;
298		return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
299	case IGMPV3_BLOCK_OLD_SOURCES:
300		if (pmc->sfmode == MCAST_INCLUDE)
301			return gdeleted || (psf->sf_crcount && sdeleted);
302		return psf->sf_crcount && !gdeleted && !sdeleted;
303	}
304	return 0;
305}
306
307static int
308igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
309{
310	struct ip_sf_list *psf;
311	int scount = 0;
312
313	for (psf = pmc->sources; psf; psf = psf->sf_next) {
314		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
315			continue;
316		scount++;
317	}
318	return scount;
319}
320
321#define igmp_skb_size(skb) (*(unsigned int *)((skb)->cb))
322
323static struct sk_buff *igmpv3_newpack(struct net_device *dev, int size)
324{
325	struct sk_buff *skb;
326	struct rtable *rt;
327	struct iphdr *pip;
328	struct igmpv3_report *pig;
329	struct net *net = dev_net(dev);
330	struct flowi4 fl4;
331	int hlen = LL_RESERVED_SPACE(dev);
332	int tlen = dev->needed_tailroom;
333
334	while (1) {
335		skb = alloc_skb(size + hlen + tlen,
336				GFP_ATOMIC | __GFP_NOWARN);
337		if (skb)
338			break;
339		size >>= 1;
340		if (size < 256)
341			return NULL;
342	}
343	skb->priority = TC_PRIO_CONTROL;
344	igmp_skb_size(skb) = size;
345
346	rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0,
347				   0, 0,
348				   IPPROTO_IGMP, 0, dev->ifindex);
349	if (IS_ERR(rt)) {
350		kfree_skb(skb);
351		return NULL;
352	}
353
354	skb_dst_set(skb, &rt->dst);
355	skb->dev = dev;
356
357	skb_reserve(skb, hlen);
358
359	skb_reset_network_header(skb);
360	pip = ip_hdr(skb);
361	skb_put(skb, sizeof(struct iphdr) + 4);
362
363	pip->version  = 4;
364	pip->ihl      = (sizeof(struct iphdr)+4)>>2;
365	pip->tos      = 0xc0;
366	pip->frag_off = htons(IP_DF);
367	pip->ttl      = 1;
368	pip->daddr    = fl4.daddr;
369	pip->saddr    = fl4.saddr;
370	pip->protocol = IPPROTO_IGMP;
371	pip->tot_len  = 0;	/* filled in later */
372	ip_select_ident(skb, NULL);
373	((u8 *)&pip[1])[0] = IPOPT_RA;
374	((u8 *)&pip[1])[1] = 4;
375	((u8 *)&pip[1])[2] = 0;
376	((u8 *)&pip[1])[3] = 0;
377
378	skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
379	skb_put(skb, sizeof(*pig));
380	pig = igmpv3_report_hdr(skb);
381	pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
382	pig->resv1 = 0;
383	pig->csum = 0;
384	pig->resv2 = 0;
385	pig->ngrec = 0;
386	return skb;
387}
388
389static int igmpv3_sendpack(struct sk_buff *skb)
390{
391	struct igmphdr *pig = igmp_hdr(skb);
392	const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
393
394	pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
395
396	return ip_local_out(skb);
397}
398
399static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
400{
401	return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
402}
403
404static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
405	int type, struct igmpv3_grec **ppgr)
406{
407	struct net_device *dev = pmc->interface->dev;
408	struct igmpv3_report *pih;
409	struct igmpv3_grec *pgr;
410
411	if (!skb)
412		skb = igmpv3_newpack(dev, dev->mtu);
413	if (!skb)
414		return NULL;
415	pgr = (struct igmpv3_grec *)skb_put(skb, sizeof(struct igmpv3_grec));
416	pgr->grec_type = type;
417	pgr->grec_auxwords = 0;
418	pgr->grec_nsrcs = 0;
419	pgr->grec_mca = pmc->multiaddr;
420	pih = igmpv3_report_hdr(skb);
421	pih->ngrec = htons(ntohs(pih->ngrec)+1);
422	*ppgr = pgr;
423	return skb;
424}
425
426#define AVAILABLE(skb) ((skb) ? ((skb)->dev ? igmp_skb_size(skb) - (skb)->len : \
427	skb_tailroom(skb)) : 0)
428
429static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
430	int type, int gdeleted, int sdeleted)
431{
432	struct net_device *dev = pmc->interface->dev;
433	struct igmpv3_report *pih;
434	struct igmpv3_grec *pgr = NULL;
435	struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
436	int scount, stotal, first, isquery, truncate;
437
438	if (pmc->multiaddr == IGMP_ALL_HOSTS)
439		return skb;
440
441	isquery = type == IGMPV3_MODE_IS_INCLUDE ||
442		  type == IGMPV3_MODE_IS_EXCLUDE;
443	truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
444		    type == IGMPV3_CHANGE_TO_EXCLUDE;
445
446	stotal = scount = 0;
447
448	psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
449
450	if (!*psf_list)
451		goto empty_source;
452
453	pih = skb ? igmpv3_report_hdr(skb) : NULL;
454
455	/* EX and TO_EX get a fresh packet, if needed */
456	if (truncate) {
457		if (pih && pih->ngrec &&
458		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
459			if (skb)
460				igmpv3_sendpack(skb);
461			skb = igmpv3_newpack(dev, dev->mtu);
462		}
463	}
464	first = 1;
465	psf_prev = NULL;
466	for (psf = *psf_list; psf; psf = psf_next) {
467		__be32 *psrc;
468
469		psf_next = psf->sf_next;
470
471		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
472			psf_prev = psf;
473			continue;
474		}
475
476		/* clear marks on query responses */
477		if (isquery)
478			psf->sf_gsresp = 0;
479
480		if (AVAILABLE(skb) < sizeof(__be32) +
481		    first*sizeof(struct igmpv3_grec)) {
482			if (truncate && !first)
483				break;	 /* truncate these */
484			if (pgr)
485				pgr->grec_nsrcs = htons(scount);
486			if (skb)
487				igmpv3_sendpack(skb);
488			skb = igmpv3_newpack(dev, dev->mtu);
489			first = 1;
490			scount = 0;
491		}
492		if (first) {
493			skb = add_grhead(skb, pmc, type, &pgr);
494			first = 0;
495		}
496		if (!skb)
497			return NULL;
498		psrc = (__be32 *)skb_put(skb, sizeof(__be32));
499		*psrc = psf->sf_inaddr;
500		scount++; stotal++;
501		if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
502		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
503			psf->sf_crcount--;
504			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
505				if (psf_prev)
506					psf_prev->sf_next = psf->sf_next;
507				else
508					*psf_list = psf->sf_next;
509				kfree(psf);
510				continue;
511			}
512		}
513		psf_prev = psf;
514	}
515
516empty_source:
517	if (!stotal) {
518		if (type == IGMPV3_ALLOW_NEW_SOURCES ||
519		    type == IGMPV3_BLOCK_OLD_SOURCES)
520			return skb;
521		if (pmc->crcount || isquery) {
522			/* make sure we have room for group header */
523			if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) {
524				igmpv3_sendpack(skb);
525				skb = NULL; /* add_grhead will get a new one */
526			}
527			skb = add_grhead(skb, pmc, type, &pgr);
528		}
529	}
530	if (pgr)
531		pgr->grec_nsrcs = htons(scount);
532
533	if (isquery)
534		pmc->gsquery = 0;	/* clear query state on report */
535	return skb;
536}
537
538static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
539{
540	struct sk_buff *skb = NULL;
541	int type;
542
543	if (!pmc) {
544		rcu_read_lock();
545		for_each_pmc_rcu(in_dev, pmc) {
546			if (pmc->multiaddr == IGMP_ALL_HOSTS)
547				continue;
548			spin_lock_bh(&pmc->lock);
549			if (pmc->sfcount[MCAST_EXCLUDE])
550				type = IGMPV3_MODE_IS_EXCLUDE;
551			else
552				type = IGMPV3_MODE_IS_INCLUDE;
553			skb = add_grec(skb, pmc, type, 0, 0);
554			spin_unlock_bh(&pmc->lock);
555		}
556		rcu_read_unlock();
557	} else {
558		spin_lock_bh(&pmc->lock);
559		if (pmc->sfcount[MCAST_EXCLUDE])
560			type = IGMPV3_MODE_IS_EXCLUDE;
561		else
562			type = IGMPV3_MODE_IS_INCLUDE;
563		skb = add_grec(skb, pmc, type, 0, 0);
564		spin_unlock_bh(&pmc->lock);
565	}
566	if (!skb)
567		return 0;
568	return igmpv3_sendpack(skb);
569}
570
571/*
572 * remove zero-count source records from a source filter list
573 */
574static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
575{
576	struct ip_sf_list *psf_prev, *psf_next, *psf;
577
578	psf_prev = NULL;
579	for (psf = *ppsf; psf; psf = psf_next) {
580		psf_next = psf->sf_next;
581		if (psf->sf_crcount == 0) {
582			if (psf_prev)
583				psf_prev->sf_next = psf->sf_next;
584			else
585				*ppsf = psf->sf_next;
586			kfree(psf);
587		} else
588			psf_prev = psf;
589	}
590}
591
592static void igmpv3_send_cr(struct in_device *in_dev)
593{
594	struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
595	struct sk_buff *skb = NULL;
596	int type, dtype;
597
598	rcu_read_lock();
599	spin_lock_bh(&in_dev->mc_tomb_lock);
600
601	/* deleted MCA's */
602	pmc_prev = NULL;
603	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) {
604		pmc_next = pmc->next;
605		if (pmc->sfmode == MCAST_INCLUDE) {
606			type = IGMPV3_BLOCK_OLD_SOURCES;
607			dtype = IGMPV3_BLOCK_OLD_SOURCES;
608			skb = add_grec(skb, pmc, type, 1, 0);
609			skb = add_grec(skb, pmc, dtype, 1, 1);
610		}
611		if (pmc->crcount) {
612			if (pmc->sfmode == MCAST_EXCLUDE) {
613				type = IGMPV3_CHANGE_TO_INCLUDE;
614				skb = add_grec(skb, pmc, type, 1, 0);
615			}
616			pmc->crcount--;
617			if (pmc->crcount == 0) {
618				igmpv3_clear_zeros(&pmc->tomb);
619				igmpv3_clear_zeros(&pmc->sources);
620			}
621		}
622		if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
623			if (pmc_prev)
624				pmc_prev->next = pmc_next;
625			else
626				in_dev->mc_tomb = pmc_next;
627			in_dev_put(pmc->interface);
628			kfree(pmc);
629		} else
630			pmc_prev = pmc;
631	}
632	spin_unlock_bh(&in_dev->mc_tomb_lock);
633
634	/* change recs */
635	for_each_pmc_rcu(in_dev, pmc) {
636		spin_lock_bh(&pmc->lock);
637		if (pmc->sfcount[MCAST_EXCLUDE]) {
638			type = IGMPV3_BLOCK_OLD_SOURCES;
639			dtype = IGMPV3_ALLOW_NEW_SOURCES;
640		} else {
641			type = IGMPV3_ALLOW_NEW_SOURCES;
642			dtype = IGMPV3_BLOCK_OLD_SOURCES;
643		}
644		skb = add_grec(skb, pmc, type, 0, 0);
645		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
646
647		/* filter mode changes */
648		if (pmc->crcount) {
649			if (pmc->sfmode == MCAST_EXCLUDE)
650				type = IGMPV3_CHANGE_TO_EXCLUDE;
651			else
652				type = IGMPV3_CHANGE_TO_INCLUDE;
653			skb = add_grec(skb, pmc, type, 0, 0);
654			pmc->crcount--;
655		}
656		spin_unlock_bh(&pmc->lock);
657	}
658	rcu_read_unlock();
659
660	if (!skb)
661		return;
662	(void) igmpv3_sendpack(skb);
663}
664
665static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
666	int type)
667{
668	struct sk_buff *skb;
669	struct iphdr *iph;
670	struct igmphdr *ih;
671	struct rtable *rt;
672	struct net_device *dev = in_dev->dev;
673	struct net *net = dev_net(dev);
674	__be32	group = pmc ? pmc->multiaddr : 0;
675	struct flowi4 fl4;
676	__be32	dst;
677	int hlen, tlen;
678
679	if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
680		return igmpv3_send_report(in_dev, pmc);
681	else if (type == IGMP_HOST_LEAVE_MESSAGE)
682		dst = IGMP_ALL_ROUTER;
683	else
684		dst = group;
685
686	rt = ip_route_output_ports(net, &fl4, NULL, dst, 0,
687				   0, 0,
688				   IPPROTO_IGMP, 0, dev->ifindex);
689	if (IS_ERR(rt))
690		return -1;
691
692	hlen = LL_RESERVED_SPACE(dev);
693	tlen = dev->needed_tailroom;
694	skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC);
695	if (skb == NULL) {
696		ip_rt_put(rt);
697		return -1;
698	}
699	skb->priority = TC_PRIO_CONTROL;
700
701	skb_dst_set(skb, &rt->dst);
702
703	skb_reserve(skb, hlen);
704
705	skb_reset_network_header(skb);
706	iph = ip_hdr(skb);
707	skb_put(skb, sizeof(struct iphdr) + 4);
708
709	iph->version  = 4;
710	iph->ihl      = (sizeof(struct iphdr)+4)>>2;
711	iph->tos      = 0xc0;
712	iph->frag_off = htons(IP_DF);
713	iph->ttl      = 1;
714	iph->daddr    = dst;
715	iph->saddr    = fl4.saddr;
716	iph->protocol = IPPROTO_IGMP;
717	ip_select_ident(skb, NULL);
718	((u8 *)&iph[1])[0] = IPOPT_RA;
719	((u8 *)&iph[1])[1] = 4;
720	((u8 *)&iph[1])[2] = 0;
721	((u8 *)&iph[1])[3] = 0;
722
723	ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
724	ih->type = type;
725	ih->code = 0;
726	ih->csum = 0;
727	ih->group = group;
728	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
729
730	return ip_local_out(skb);
731}
732
733static void igmp_gq_timer_expire(unsigned long data)
734{
735	struct in_device *in_dev = (struct in_device *)data;
736
737	in_dev->mr_gq_running = 0;
738	igmpv3_send_report(in_dev, NULL);
739	in_dev_put(in_dev);
740}
741
742static void igmp_ifc_timer_expire(unsigned long data)
743{
744	struct in_device *in_dev = (struct in_device *)data;
745
746	igmpv3_send_cr(in_dev);
747	if (in_dev->mr_ifc_count) {
748		in_dev->mr_ifc_count--;
749		igmp_ifc_start_timer(in_dev,
750				     unsolicited_report_interval(in_dev));
751	}
752	in_dev_put(in_dev);
753}
754
755static void igmp_ifc_event(struct in_device *in_dev)
756{
757	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
758		return;
759	in_dev->mr_ifc_count = in_dev->mr_qrv ? in_dev->mr_qrv :
760		IGMP_Unsolicited_Report_Count;
761	igmp_ifc_start_timer(in_dev, 1);
762}
763
764
765static void igmp_timer_expire(unsigned long data)
766{
767	struct ip_mc_list *im = (struct ip_mc_list *)data;
768	struct in_device *in_dev = im->interface;
769
770	spin_lock(&im->lock);
771	im->tm_running = 0;
772
773	if (im->unsolicit_count) {
774		im->unsolicit_count--;
775		igmp_start_timer(im, unsolicited_report_interval(in_dev));
776	}
777	im->reporter = 1;
778	spin_unlock(&im->lock);
779
780	if (IGMP_V1_SEEN(in_dev))
781		igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
782	else if (IGMP_V2_SEEN(in_dev))
783		igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
784	else
785		igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
786
787	ip_ma_put(im);
788}
789
790/* mark EXCLUDE-mode sources */
791static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
792{
793	struct ip_sf_list *psf;
794	int i, scount;
795
796	scount = 0;
797	for (psf = pmc->sources; psf; psf = psf->sf_next) {
798		if (scount == nsrcs)
799			break;
800		for (i = 0; i < nsrcs; i++) {
801			/* skip inactive filters */
802			if (psf->sf_count[MCAST_INCLUDE] ||
803			    pmc->sfcount[MCAST_EXCLUDE] !=
804			    psf->sf_count[MCAST_EXCLUDE])
805				break;
806			if (srcs[i] == psf->sf_inaddr) {
807				scount++;
808				break;
809			}
810		}
811	}
812	pmc->gsquery = 0;
813	if (scount == nsrcs)	/* all sources excluded */
814		return 0;
815	return 1;
816}
817
818static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
819{
820	struct ip_sf_list *psf;
821	int i, scount;
822
823	if (pmc->sfmode == MCAST_EXCLUDE)
824		return igmp_xmarksources(pmc, nsrcs, srcs);
825
826	/* mark INCLUDE-mode sources */
827	scount = 0;
828	for (psf = pmc->sources; psf; psf = psf->sf_next) {
829		if (scount == nsrcs)
830			break;
831		for (i = 0; i < nsrcs; i++)
832			if (srcs[i] == psf->sf_inaddr) {
833				psf->sf_gsresp = 1;
834				scount++;
835				break;
836			}
837	}
838	if (!scount) {
839		pmc->gsquery = 0;
840		return 0;
841	}
842	pmc->gsquery = 1;
843	return 1;
844}
845
846/* return true if packet was dropped */
847static bool igmp_heard_report(struct in_device *in_dev, __be32 group)
848{
849	struct ip_mc_list *im;
850
851	/* Timers are only set for non-local groups */
852
853	if (group == IGMP_ALL_HOSTS)
854		return false;
855
856	rcu_read_lock();
857	for_each_pmc_rcu(in_dev, im) {
858		if (im->multiaddr == group) {
859			igmp_stop_timer(im);
860			break;
861		}
862	}
863	rcu_read_unlock();
864	return false;
865}
866
867/* return true if packet was dropped */
868static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
869	int len)
870{
871	struct igmphdr 		*ih = igmp_hdr(skb);
872	struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
873	struct ip_mc_list	*im;
874	__be32			group = ih->group;
875	int			max_delay;
876	int			mark = 0;
877
878
879	if (len == 8) {
880		if (ih->code == 0) {
881			/* Alas, old v1 router presents here. */
882
883			max_delay = IGMP_Query_Response_Interval;
884			in_dev->mr_v1_seen = jiffies +
885				IGMP_V1_Router_Present_Timeout;
886			group = 0;
887		} else {
888			/* v2 router present */
889			max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
890			in_dev->mr_v2_seen = jiffies +
891				IGMP_V2_Router_Present_Timeout;
892		}
893		/* cancel the interface change timer */
894		in_dev->mr_ifc_count = 0;
895		if (del_timer(&in_dev->mr_ifc_timer))
896			__in_dev_put(in_dev);
897		/* clear deleted report items */
898		igmpv3_clear_delrec(in_dev);
899	} else if (len < 12) {
900		return true;	/* ignore bogus packet; freed by caller */
901	} else if (IGMP_V1_SEEN(in_dev)) {
902		/* This is a v3 query with v1 queriers present */
903		max_delay = IGMP_Query_Response_Interval;
904		group = 0;
905	} else if (IGMP_V2_SEEN(in_dev)) {
906		/* this is a v3 query with v2 queriers present;
907		 * Interpretation of the max_delay code is problematic here.
908		 * A real v2 host would use ih_code directly, while v3 has a
909		 * different encoding. We use the v3 encoding as more likely
910		 * to be intended in a v3 query.
911		 */
912		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
913		if (!max_delay)
914			max_delay = 1;	/* can't mod w/ 0 */
915	} else { /* v3 */
916		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
917			return true;
918
919		ih3 = igmpv3_query_hdr(skb);
920		if (ih3->nsrcs) {
921			if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
922					   + ntohs(ih3->nsrcs)*sizeof(__be32)))
923				return true;
924			ih3 = igmpv3_query_hdr(skb);
925		}
926
927		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
928		if (!max_delay)
929			max_delay = 1;	/* can't mod w/ 0 */
930		in_dev->mr_maxdelay = max_delay;
931		if (ih3->qrv)
932			in_dev->mr_qrv = ih3->qrv;
933		if (!group) { /* general query */
934			if (ih3->nsrcs)
935				return false;	/* no sources allowed */
936			igmp_gq_start_timer(in_dev);
937			return false;
938		}
939		/* mark sources to include, if group & source-specific */
940		mark = ih3->nsrcs != 0;
941	}
942
943	/*
944	 * - Start the timers in all of our membership records
945	 *   that the query applies to for the interface on
946	 *   which the query arrived excl. those that belong
947	 *   to a "local" group (224.0.0.X)
948	 * - For timers already running check if they need to
949	 *   be reset.
950	 * - Use the igmp->igmp_code field as the maximum
951	 *   delay possible
952	 */
953	rcu_read_lock();
954	for_each_pmc_rcu(in_dev, im) {
955		int changed;
956
957		if (group && group != im->multiaddr)
958			continue;
959		if (im->multiaddr == IGMP_ALL_HOSTS)
960			continue;
961		spin_lock_bh(&im->lock);
962		if (im->tm_running)
963			im->gsquery = im->gsquery && mark;
964		else
965			im->gsquery = mark;
966		changed = !im->gsquery ||
967			igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
968		spin_unlock_bh(&im->lock);
969		if (changed)
970			igmp_mod_timer(im, max_delay);
971	}
972	rcu_read_unlock();
973	return false;
974}
975
976/* called in rcu_read_lock() section */
977int igmp_rcv(struct sk_buff *skb)
978{
979	/* This basically follows the spec line by line -- see RFC1112 */
980	struct igmphdr *ih;
981	struct in_device *in_dev = __in_dev_get_rcu(skb->dev);
982	int len = skb->len;
983	bool dropped = true;
984
985	if (in_dev == NULL)
986		goto drop;
987
988	if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
989		goto drop;
990
991	if (skb_checksum_simple_validate(skb))
992		goto drop;
993
994	ih = igmp_hdr(skb);
995	switch (ih->type) {
996	case IGMP_HOST_MEMBERSHIP_QUERY:
997		dropped = igmp_heard_query(in_dev, skb, len);
998		break;
999	case IGMP_HOST_MEMBERSHIP_REPORT:
1000	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1001		/* Is it our report looped back? */
1002		if (rt_is_output_route(skb_rtable(skb)))
1003			break;
1004		/* don't rely on MC router hearing unicast reports */
1005		if (skb->pkt_type == PACKET_MULTICAST ||
1006		    skb->pkt_type == PACKET_BROADCAST)
1007			dropped = igmp_heard_report(in_dev, ih->group);
1008		break;
1009	case IGMP_PIM:
1010#ifdef CONFIG_IP_PIMSM_V1
1011		return pim_rcv_v1(skb);
1012#endif
1013	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1014	case IGMP_DVMRP:
1015	case IGMP_TRACE:
1016	case IGMP_HOST_LEAVE_MESSAGE:
1017	case IGMP_MTRACE:
1018	case IGMP_MTRACE_RESP:
1019		break;
1020	default:
1021		break;
1022	}
1023
1024drop:
1025	if (dropped)
1026		kfree_skb(skb);
1027	else
1028		consume_skb(skb);
1029	return 0;
1030}
1031
1032#endif
1033
1034
1035/*
1036 *	Add a filter to a device
1037 */
1038
1039static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1040{
1041	char buf[MAX_ADDR_LEN];
1042	struct net_device *dev = in_dev->dev;
1043
1044	/* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1045	   We will get multicast token leakage, when IFF_MULTICAST
1046	   is changed. This check should be done in ndo_set_rx_mode
1047	   routine. Something sort of:
1048	   if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1049	   --ANK
1050	   */
1051	if (arp_mc_map(addr, buf, dev, 0) == 0)
1052		dev_mc_add(dev, buf);
1053}
1054
1055/*
1056 *	Remove a filter from a device
1057 */
1058
1059static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1060{
1061	char buf[MAX_ADDR_LEN];
1062	struct net_device *dev = in_dev->dev;
1063
1064	if (arp_mc_map(addr, buf, dev, 0) == 0)
1065		dev_mc_del(dev, buf);
1066}
1067
1068#ifdef CONFIG_IP_MULTICAST
1069/*
1070 * deleted ip_mc_list manipulation
1071 */
1072static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1073{
1074	struct ip_mc_list *pmc;
1075
1076	/* this is an "ip_mc_list" for convenience; only the fields below
1077	 * are actually used. In particular, the refcnt and users are not
1078	 * used for management of the delete list. Using the same structure
1079	 * for deleted items allows change reports to use common code with
1080	 * non-deleted or query-response MCA's.
1081	 */
1082	pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
1083	if (!pmc)
1084		return;
1085	spin_lock_bh(&im->lock);
1086	pmc->interface = im->interface;
1087	in_dev_hold(in_dev);
1088	pmc->multiaddr = im->multiaddr;
1089	pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1090		IGMP_Unsolicited_Report_Count;
1091	pmc->sfmode = im->sfmode;
1092	if (pmc->sfmode == MCAST_INCLUDE) {
1093		struct ip_sf_list *psf;
1094
1095		pmc->tomb = im->tomb;
1096		pmc->sources = im->sources;
1097		im->tomb = im->sources = NULL;
1098		for (psf = pmc->sources; psf; psf = psf->sf_next)
1099			psf->sf_crcount = pmc->crcount;
1100	}
1101	spin_unlock_bh(&im->lock);
1102
1103	spin_lock_bh(&in_dev->mc_tomb_lock);
1104	pmc->next = in_dev->mc_tomb;
1105	in_dev->mc_tomb = pmc;
1106	spin_unlock_bh(&in_dev->mc_tomb_lock);
1107}
1108
1109static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr)
1110{
1111	struct ip_mc_list *pmc, *pmc_prev;
1112	struct ip_sf_list *psf, *psf_next;
1113
1114	spin_lock_bh(&in_dev->mc_tomb_lock);
1115	pmc_prev = NULL;
1116	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) {
1117		if (pmc->multiaddr == multiaddr)
1118			break;
1119		pmc_prev = pmc;
1120	}
1121	if (pmc) {
1122		if (pmc_prev)
1123			pmc_prev->next = pmc->next;
1124		else
1125			in_dev->mc_tomb = pmc->next;
1126	}
1127	spin_unlock_bh(&in_dev->mc_tomb_lock);
1128	if (pmc) {
1129		for (psf = pmc->tomb; psf; psf = psf_next) {
1130			psf_next = psf->sf_next;
1131			kfree(psf);
1132		}
1133		in_dev_put(pmc->interface);
1134		kfree(pmc);
1135	}
1136}
1137
1138static void igmpv3_clear_delrec(struct in_device *in_dev)
1139{
1140	struct ip_mc_list *pmc, *nextpmc;
1141
1142	spin_lock_bh(&in_dev->mc_tomb_lock);
1143	pmc = in_dev->mc_tomb;
1144	in_dev->mc_tomb = NULL;
1145	spin_unlock_bh(&in_dev->mc_tomb_lock);
1146
1147	for (; pmc; pmc = nextpmc) {
1148		nextpmc = pmc->next;
1149		ip_mc_clear_src(pmc);
1150		in_dev_put(pmc->interface);
1151		kfree(pmc);
1152	}
1153	/* clear dead sources, too */
1154	rcu_read_lock();
1155	for_each_pmc_rcu(in_dev, pmc) {
1156		struct ip_sf_list *psf, *psf_next;
1157
1158		spin_lock_bh(&pmc->lock);
1159		psf = pmc->tomb;
1160		pmc->tomb = NULL;
1161		spin_unlock_bh(&pmc->lock);
1162		for (; psf; psf = psf_next) {
1163			psf_next = psf->sf_next;
1164			kfree(psf);
1165		}
1166	}
1167	rcu_read_unlock();
1168}
1169#endif
1170
1171static void igmp_group_dropped(struct ip_mc_list *im)
1172{
1173	struct in_device *in_dev = im->interface;
1174#ifdef CONFIG_IP_MULTICAST
1175	int reporter;
1176#endif
1177
1178	if (im->loaded) {
1179		im->loaded = 0;
1180		ip_mc_filter_del(in_dev, im->multiaddr);
1181	}
1182
1183#ifdef CONFIG_IP_MULTICAST
1184	if (im->multiaddr == IGMP_ALL_HOSTS)
1185		return;
1186
1187	reporter = im->reporter;
1188	igmp_stop_timer(im);
1189
1190	if (!in_dev->dead) {
1191		if (IGMP_V1_SEEN(in_dev))
1192			return;
1193		if (IGMP_V2_SEEN(in_dev)) {
1194			if (reporter)
1195				igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1196			return;
1197		}
1198		/* IGMPv3 */
1199		igmpv3_add_delrec(in_dev, im);
1200
1201		igmp_ifc_event(in_dev);
1202	}
1203#endif
1204}
1205
1206static void igmp_group_added(struct ip_mc_list *im)
1207{
1208	struct in_device *in_dev = im->interface;
1209
1210	if (im->loaded == 0) {
1211		im->loaded = 1;
1212		ip_mc_filter_add(in_dev, im->multiaddr);
1213	}
1214
1215#ifdef CONFIG_IP_MULTICAST
1216	if (im->multiaddr == IGMP_ALL_HOSTS)
1217		return;
1218
1219	if (in_dev->dead)
1220		return;
1221	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1222		spin_lock_bh(&im->lock);
1223		igmp_start_timer(im, IGMP_Initial_Report_Delay);
1224		spin_unlock_bh(&im->lock);
1225		return;
1226	}
1227	/* else, v3 */
1228
1229	im->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1230		IGMP_Unsolicited_Report_Count;
1231	igmp_ifc_event(in_dev);
1232#endif
1233}
1234
1235
1236/*
1237 *	Multicast list managers
1238 */
1239
1240static u32 ip_mc_hash(const struct ip_mc_list *im)
1241{
1242	return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
1243}
1244
1245static void ip_mc_hash_add(struct in_device *in_dev,
1246			   struct ip_mc_list *im)
1247{
1248	struct ip_mc_list __rcu **mc_hash;
1249	u32 hash;
1250
1251	mc_hash = rtnl_dereference(in_dev->mc_hash);
1252	if (mc_hash) {
1253		hash = ip_mc_hash(im);
1254		im->next_hash = mc_hash[hash];
1255		rcu_assign_pointer(mc_hash[hash], im);
1256		return;
1257	}
1258
1259	/* do not use a hash table for small number of items */
1260	if (in_dev->mc_count < 4)
1261		return;
1262
1263	mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
1264			  GFP_KERNEL);
1265	if (!mc_hash)
1266		return;
1267
1268	for_each_pmc_rtnl(in_dev, im) {
1269		hash = ip_mc_hash(im);
1270		im->next_hash = mc_hash[hash];
1271		RCU_INIT_POINTER(mc_hash[hash], im);
1272	}
1273
1274	rcu_assign_pointer(in_dev->mc_hash, mc_hash);
1275}
1276
1277static void ip_mc_hash_remove(struct in_device *in_dev,
1278			      struct ip_mc_list *im)
1279{
1280	struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
1281	struct ip_mc_list *aux;
1282
1283	if (!mc_hash)
1284		return;
1285	mc_hash += ip_mc_hash(im);
1286	while ((aux = rtnl_dereference(*mc_hash)) != im)
1287		mc_hash = &aux->next_hash;
1288	*mc_hash = im->next_hash;
1289}
1290
1291
1292/*
1293 *	A socket has joined a multicast group on device dev.
1294 */
1295
1296void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1297{
1298	struct ip_mc_list *im;
1299
1300	ASSERT_RTNL();
1301
1302	for_each_pmc_rtnl(in_dev, im) {
1303		if (im->multiaddr == addr) {
1304			im->users++;
1305			ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1306			goto out;
1307		}
1308	}
1309
1310	im = kzalloc(sizeof(*im), GFP_KERNEL);
1311	if (!im)
1312		goto out;
1313
1314	im->users = 1;
1315	im->interface = in_dev;
1316	in_dev_hold(in_dev);
1317	im->multiaddr = addr;
1318	/* initial mode is (EX, empty) */
1319	im->sfmode = MCAST_EXCLUDE;
1320	im->sfcount[MCAST_EXCLUDE] = 1;
1321	atomic_set(&im->refcnt, 1);
1322	spin_lock_init(&im->lock);
1323#ifdef CONFIG_IP_MULTICAST
1324	setup_timer(&im->timer, igmp_timer_expire, (unsigned long)im);
1325	im->unsolicit_count = IGMP_Unsolicited_Report_Count;
1326#endif
1327
1328	im->next_rcu = in_dev->mc_list;
1329	in_dev->mc_count++;
1330	rcu_assign_pointer(in_dev->mc_list, im);
1331
1332	ip_mc_hash_add(in_dev, im);
1333
1334#ifdef CONFIG_IP_MULTICAST
1335	igmpv3_del_delrec(in_dev, im->multiaddr);
1336#endif
1337	igmp_group_added(im);
1338	if (!in_dev->dead)
1339		ip_rt_multicast_event(in_dev);
1340out:
1341	return;
1342}
1343EXPORT_SYMBOL(ip_mc_inc_group);
1344
1345/*
1346 *	Resend IGMP JOIN report; used by netdev notifier.
1347 */
1348static void ip_mc_rejoin_groups(struct in_device *in_dev)
1349{
1350#ifdef CONFIG_IP_MULTICAST
1351	struct ip_mc_list *im;
1352	int type;
1353
1354	ASSERT_RTNL();
1355
1356	for_each_pmc_rtnl(in_dev, im) {
1357		if (im->multiaddr == IGMP_ALL_HOSTS)
1358			continue;
1359
1360		/* a failover is happening and switches
1361		 * must be notified immediately
1362		 */
1363		if (IGMP_V1_SEEN(in_dev))
1364			type = IGMP_HOST_MEMBERSHIP_REPORT;
1365		else if (IGMP_V2_SEEN(in_dev))
1366			type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1367		else
1368			type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1369		igmp_send_report(in_dev, im, type);
1370	}
1371#endif
1372}
1373
1374/*
1375 *	A socket has left a multicast group on device dev
1376 */
1377
1378void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
1379{
1380	struct ip_mc_list *i;
1381	struct ip_mc_list __rcu **ip;
1382
1383	ASSERT_RTNL();
1384
1385	for (ip = &in_dev->mc_list;
1386	     (i = rtnl_dereference(*ip)) != NULL;
1387	     ip = &i->next_rcu) {
1388		if (i->multiaddr == addr) {
1389			if (--i->users == 0) {
1390				ip_mc_hash_remove(in_dev, i);
1391				*ip = i->next_rcu;
1392				in_dev->mc_count--;
1393				igmp_group_dropped(i);
1394				ip_mc_clear_src(i);
1395
1396				if (!in_dev->dead)
1397					ip_rt_multicast_event(in_dev);
1398
1399				ip_ma_put(i);
1400				return;
1401			}
1402			break;
1403		}
1404	}
1405}
1406EXPORT_SYMBOL(ip_mc_dec_group);
1407
1408/* Device changing type */
1409
1410void ip_mc_unmap(struct in_device *in_dev)
1411{
1412	struct ip_mc_list *pmc;
1413
1414	ASSERT_RTNL();
1415
1416	for_each_pmc_rtnl(in_dev, pmc)
1417		igmp_group_dropped(pmc);
1418}
1419
1420void ip_mc_remap(struct in_device *in_dev)
1421{
1422	struct ip_mc_list *pmc;
1423
1424	ASSERT_RTNL();
1425
1426	for_each_pmc_rtnl(in_dev, pmc)
1427		igmp_group_added(pmc);
1428}
1429
1430/* Device going down */
1431
1432void ip_mc_down(struct in_device *in_dev)
1433{
1434	struct ip_mc_list *pmc;
1435
1436	ASSERT_RTNL();
1437
1438	for_each_pmc_rtnl(in_dev, pmc)
1439		igmp_group_dropped(pmc);
1440
1441#ifdef CONFIG_IP_MULTICAST
1442	in_dev->mr_ifc_count = 0;
1443	if (del_timer(&in_dev->mr_ifc_timer))
1444		__in_dev_put(in_dev);
1445	in_dev->mr_gq_running = 0;
1446	if (del_timer(&in_dev->mr_gq_timer))
1447		__in_dev_put(in_dev);
1448	igmpv3_clear_delrec(in_dev);
1449#endif
1450
1451	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1452}
1453
1454void ip_mc_init_dev(struct in_device *in_dev)
1455{
1456	ASSERT_RTNL();
1457
1458#ifdef CONFIG_IP_MULTICAST
1459	setup_timer(&in_dev->mr_gq_timer, igmp_gq_timer_expire,
1460			(unsigned long)in_dev);
1461	setup_timer(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire,
1462			(unsigned long)in_dev);
1463	in_dev->mr_qrv = IGMP_Unsolicited_Report_Count;
1464#endif
1465
1466	spin_lock_init(&in_dev->mc_tomb_lock);
1467}
1468
1469/* Device going up */
1470
1471void ip_mc_up(struct in_device *in_dev)
1472{
1473	struct ip_mc_list *pmc;
1474
1475	ASSERT_RTNL();
1476
1477	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1478
1479	for_each_pmc_rtnl(in_dev, pmc)
1480		igmp_group_added(pmc);
1481}
1482
1483/*
1484 *	Device is about to be destroyed: clean up.
1485 */
1486
1487void ip_mc_destroy_dev(struct in_device *in_dev)
1488{
1489	struct ip_mc_list *i;
1490
1491	ASSERT_RTNL();
1492
1493	/* Deactivate timers */
1494	ip_mc_down(in_dev);
1495
1496	while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1497		in_dev->mc_list = i->next_rcu;
1498		in_dev->mc_count--;
1499
1500		/* We've dropped the groups in ip_mc_down already */
1501		ip_mc_clear_src(i);
1502		ip_ma_put(i);
1503	}
1504}
1505
1506/* RTNL is locked */
1507static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1508{
1509	struct net_device *dev = NULL;
1510	struct in_device *idev = NULL;
1511
1512	if (imr->imr_ifindex) {
1513		idev = inetdev_by_index(net, imr->imr_ifindex);
1514		return idev;
1515	}
1516	if (imr->imr_address.s_addr) {
1517		dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1518		if (!dev)
1519			return NULL;
1520	}
1521
1522	if (!dev) {
1523		struct rtable *rt = ip_route_output(net,
1524						    imr->imr_multiaddr.s_addr,
1525						    0, 0, 0);
1526		if (!IS_ERR(rt)) {
1527			dev = rt->dst.dev;
1528			ip_rt_put(rt);
1529		}
1530	}
1531	if (dev) {
1532		imr->imr_ifindex = dev->ifindex;
1533		idev = __in_dev_get_rtnl(dev);
1534	}
1535	return idev;
1536}
1537
1538/*
1539 *	Join a socket to a group
1540 */
1541int sysctl_igmp_max_memberships __read_mostly = IP_MAX_MEMBERSHIPS;
1542int sysctl_igmp_max_msf __read_mostly = IP_MAX_MSF;
1543
1544
1545static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1546	__be32 *psfsrc)
1547{
1548	struct ip_sf_list *psf, *psf_prev;
1549	int rv = 0;
1550
1551	psf_prev = NULL;
1552	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1553		if (psf->sf_inaddr == *psfsrc)
1554			break;
1555		psf_prev = psf;
1556	}
1557	if (!psf || psf->sf_count[sfmode] == 0) {
1558		/* source filter not found, or count wrong =>  bug */
1559		return -ESRCH;
1560	}
1561	psf->sf_count[sfmode]--;
1562	if (psf->sf_count[sfmode] == 0) {
1563		ip_rt_multicast_event(pmc->interface);
1564	}
1565	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1566#ifdef CONFIG_IP_MULTICAST
1567		struct in_device *in_dev = pmc->interface;
1568#endif
1569
1570		/* no more filters for this source */
1571		if (psf_prev)
1572			psf_prev->sf_next = psf->sf_next;
1573		else
1574			pmc->sources = psf->sf_next;
1575#ifdef CONFIG_IP_MULTICAST
1576		if (psf->sf_oldin &&
1577		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1578			psf->sf_crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1579				IGMP_Unsolicited_Report_Count;
1580			psf->sf_next = pmc->tomb;
1581			pmc->tomb = psf;
1582			rv = 1;
1583		} else
1584#endif
1585			kfree(psf);
1586	}
1587	return rv;
1588}
1589
1590#ifndef CONFIG_IP_MULTICAST
1591#define igmp_ifc_event(x)	do { } while (0)
1592#endif
1593
1594static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1595			 int sfcount, __be32 *psfsrc, int delta)
1596{
1597	struct ip_mc_list *pmc;
1598	int	changerec = 0;
1599	int	i, err;
1600
1601	if (!in_dev)
1602		return -ENODEV;
1603	rcu_read_lock();
1604	for_each_pmc_rcu(in_dev, pmc) {
1605		if (*pmca == pmc->multiaddr)
1606			break;
1607	}
1608	if (!pmc) {
1609		/* MCA not found?? bug */
1610		rcu_read_unlock();
1611		return -ESRCH;
1612	}
1613	spin_lock_bh(&pmc->lock);
1614	rcu_read_unlock();
1615#ifdef CONFIG_IP_MULTICAST
1616	sf_markstate(pmc);
1617#endif
1618	if (!delta) {
1619		err = -EINVAL;
1620		if (!pmc->sfcount[sfmode])
1621			goto out_unlock;
1622		pmc->sfcount[sfmode]--;
1623	}
1624	err = 0;
1625	for (i = 0; i < sfcount; i++) {
1626		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1627
1628		changerec |= rv > 0;
1629		if (!err && rv < 0)
1630			err = rv;
1631	}
1632	if (pmc->sfmode == MCAST_EXCLUDE &&
1633	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1634	    pmc->sfcount[MCAST_INCLUDE]) {
1635#ifdef CONFIG_IP_MULTICAST
1636		struct ip_sf_list *psf;
1637#endif
1638
1639		/* filter mode change */
1640		pmc->sfmode = MCAST_INCLUDE;
1641#ifdef CONFIG_IP_MULTICAST
1642		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1643			IGMP_Unsolicited_Report_Count;
1644		in_dev->mr_ifc_count = pmc->crcount;
1645		for (psf = pmc->sources; psf; psf = psf->sf_next)
1646			psf->sf_crcount = 0;
1647		igmp_ifc_event(pmc->interface);
1648	} else if (sf_setstate(pmc) || changerec) {
1649		igmp_ifc_event(pmc->interface);
1650#endif
1651	}
1652out_unlock:
1653	spin_unlock_bh(&pmc->lock);
1654	return err;
1655}
1656
1657/*
1658 * Add multicast single-source filter to the interface list
1659 */
1660static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1661	__be32 *psfsrc)
1662{
1663	struct ip_sf_list *psf, *psf_prev;
1664
1665	psf_prev = NULL;
1666	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1667		if (psf->sf_inaddr == *psfsrc)
1668			break;
1669		psf_prev = psf;
1670	}
1671	if (!psf) {
1672		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1673		if (!psf)
1674			return -ENOBUFS;
1675		psf->sf_inaddr = *psfsrc;
1676		if (psf_prev) {
1677			psf_prev->sf_next = psf;
1678		} else
1679			pmc->sources = psf;
1680	}
1681	psf->sf_count[sfmode]++;
1682	if (psf->sf_count[sfmode] == 1) {
1683		ip_rt_multicast_event(pmc->interface);
1684	}
1685	return 0;
1686}
1687
1688#ifdef CONFIG_IP_MULTICAST
1689static void sf_markstate(struct ip_mc_list *pmc)
1690{
1691	struct ip_sf_list *psf;
1692	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1693
1694	for (psf = pmc->sources; psf; psf = psf->sf_next)
1695		if (pmc->sfcount[MCAST_EXCLUDE]) {
1696			psf->sf_oldin = mca_xcount ==
1697				psf->sf_count[MCAST_EXCLUDE] &&
1698				!psf->sf_count[MCAST_INCLUDE];
1699		} else
1700			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1701}
1702
1703static int sf_setstate(struct ip_mc_list *pmc)
1704{
1705	struct ip_sf_list *psf, *dpsf;
1706	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1707	int qrv = pmc->interface->mr_qrv;
1708	int new_in, rv;
1709
1710	rv = 0;
1711	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1712		if (pmc->sfcount[MCAST_EXCLUDE]) {
1713			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1714				!psf->sf_count[MCAST_INCLUDE];
1715		} else
1716			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1717		if (new_in) {
1718			if (!psf->sf_oldin) {
1719				struct ip_sf_list *prev = NULL;
1720
1721				for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) {
1722					if (dpsf->sf_inaddr == psf->sf_inaddr)
1723						break;
1724					prev = dpsf;
1725				}
1726				if (dpsf) {
1727					if (prev)
1728						prev->sf_next = dpsf->sf_next;
1729					else
1730						pmc->tomb = dpsf->sf_next;
1731					kfree(dpsf);
1732				}
1733				psf->sf_crcount = qrv;
1734				rv++;
1735			}
1736		} else if (psf->sf_oldin) {
1737
1738			psf->sf_crcount = 0;
1739			/*
1740			 * add or update "delete" records if an active filter
1741			 * is now inactive
1742			 */
1743			for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next)
1744				if (dpsf->sf_inaddr == psf->sf_inaddr)
1745					break;
1746			if (!dpsf) {
1747				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
1748				if (!dpsf)
1749					continue;
1750				*dpsf = *psf;
1751				/* pmc->lock held by callers */
1752				dpsf->sf_next = pmc->tomb;
1753				pmc->tomb = dpsf;
1754			}
1755			dpsf->sf_crcount = qrv;
1756			rv++;
1757		}
1758	}
1759	return rv;
1760}
1761#endif
1762
1763/*
1764 * Add multicast source filter list to the interface list
1765 */
1766static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1767			 int sfcount, __be32 *psfsrc, int delta)
1768{
1769	struct ip_mc_list *pmc;
1770	int	isexclude;
1771	int	i, err;
1772
1773	if (!in_dev)
1774		return -ENODEV;
1775	rcu_read_lock();
1776	for_each_pmc_rcu(in_dev, pmc) {
1777		if (*pmca == pmc->multiaddr)
1778			break;
1779	}
1780	if (!pmc) {
1781		/* MCA not found?? bug */
1782		rcu_read_unlock();
1783		return -ESRCH;
1784	}
1785	spin_lock_bh(&pmc->lock);
1786	rcu_read_unlock();
1787
1788#ifdef CONFIG_IP_MULTICAST
1789	sf_markstate(pmc);
1790#endif
1791	isexclude = pmc->sfmode == MCAST_EXCLUDE;
1792	if (!delta)
1793		pmc->sfcount[sfmode]++;
1794	err = 0;
1795	for (i = 0; i < sfcount; i++) {
1796		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]);
1797		if (err)
1798			break;
1799	}
1800	if (err) {
1801		int j;
1802
1803		if (!delta)
1804			pmc->sfcount[sfmode]--;
1805		for (j = 0; j < i; j++)
1806			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
1807	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
1808#ifdef CONFIG_IP_MULTICAST
1809		struct ip_sf_list *psf;
1810		in_dev = pmc->interface;
1811#endif
1812
1813		/* filter mode change */
1814		if (pmc->sfcount[MCAST_EXCLUDE])
1815			pmc->sfmode = MCAST_EXCLUDE;
1816		else if (pmc->sfcount[MCAST_INCLUDE])
1817			pmc->sfmode = MCAST_INCLUDE;
1818#ifdef CONFIG_IP_MULTICAST
1819		/* else no filters; keep old mode for reports */
1820
1821		pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1822			IGMP_Unsolicited_Report_Count;
1823		in_dev->mr_ifc_count = pmc->crcount;
1824		for (psf = pmc->sources; psf; psf = psf->sf_next)
1825			psf->sf_crcount = 0;
1826		igmp_ifc_event(in_dev);
1827	} else if (sf_setstate(pmc)) {
1828		igmp_ifc_event(in_dev);
1829#endif
1830	}
1831	spin_unlock_bh(&pmc->lock);
1832	return err;
1833}
1834
1835static void ip_mc_clear_src(struct ip_mc_list *pmc)
1836{
1837	struct ip_sf_list *psf, *nextpsf;
1838
1839	for (psf = pmc->tomb; psf; psf = nextpsf) {
1840		nextpsf = psf->sf_next;
1841		kfree(psf);
1842	}
1843	pmc->tomb = NULL;
1844	for (psf = pmc->sources; psf; psf = nextpsf) {
1845		nextpsf = psf->sf_next;
1846		kfree(psf);
1847	}
1848	pmc->sources = NULL;
1849	pmc->sfmode = MCAST_EXCLUDE;
1850	pmc->sfcount[MCAST_INCLUDE] = 0;
1851	pmc->sfcount[MCAST_EXCLUDE] = 1;
1852}
1853
1854
1855/*
1856 * Join a multicast group
1857 */
1858int ip_mc_join_group(struct sock *sk , struct ip_mreqn *imr)
1859{
1860	int err;
1861	__be32 addr = imr->imr_multiaddr.s_addr;
1862	struct ip_mc_socklist *iml = NULL, *i;
1863	struct in_device *in_dev;
1864	struct inet_sock *inet = inet_sk(sk);
1865	struct net *net = sock_net(sk);
1866	int ifindex;
1867	int count = 0;
1868
1869	if (!ipv4_is_multicast(addr))
1870		return -EINVAL;
1871
1872	rtnl_lock();
1873
1874	in_dev = ip_mc_find_dev(net, imr);
1875
1876	if (!in_dev) {
1877		iml = NULL;
1878		err = -ENODEV;
1879		goto done;
1880	}
1881
1882	err = -EADDRINUSE;
1883	ifindex = imr->imr_ifindex;
1884	for_each_pmc_rtnl(inet, i) {
1885		if (i->multi.imr_multiaddr.s_addr == addr &&
1886		    i->multi.imr_ifindex == ifindex)
1887			goto done;
1888		count++;
1889	}
1890	err = -ENOBUFS;
1891	if (count >= sysctl_igmp_max_memberships)
1892		goto done;
1893	iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
1894	if (iml == NULL)
1895		goto done;
1896
1897	memcpy(&iml->multi, imr, sizeof(*imr));
1898	iml->next_rcu = inet->mc_list;
1899	iml->sflist = NULL;
1900	iml->sfmode = MCAST_EXCLUDE;
1901	rcu_assign_pointer(inet->mc_list, iml);
1902	ip_mc_inc_group(in_dev, addr);
1903	err = 0;
1904done:
1905	rtnl_unlock();
1906	return err;
1907}
1908EXPORT_SYMBOL(ip_mc_join_group);
1909
1910static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
1911			   struct in_device *in_dev)
1912{
1913	struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
1914	int err;
1915
1916	if (psf == NULL) {
1917		/* any-source empty exclude case */
1918		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1919			iml->sfmode, 0, NULL, 0);
1920	}
1921	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1922			iml->sfmode, psf->sl_count, psf->sl_addr, 0);
1923	RCU_INIT_POINTER(iml->sflist, NULL);
1924	/* decrease mem now to avoid the memleak warning */
1925	atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc);
1926	kfree_rcu(psf, rcu);
1927	return err;
1928}
1929
1930/*
1931 *	Ask a socket to leave a group.
1932 */
1933
1934int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
1935{
1936	struct inet_sock *inet = inet_sk(sk);
1937	struct ip_mc_socklist *iml;
1938	struct ip_mc_socklist __rcu **imlp;
1939	struct in_device *in_dev;
1940	struct net *net = sock_net(sk);
1941	__be32 group = imr->imr_multiaddr.s_addr;
1942	u32 ifindex;
1943	int ret = -EADDRNOTAVAIL;
1944
1945	rtnl_lock();
1946	in_dev = ip_mc_find_dev(net, imr);
1947	if (!in_dev) {
1948		ret = -ENODEV;
1949		goto out;
1950	}
1951	ifindex = imr->imr_ifindex;
1952	for (imlp = &inet->mc_list;
1953	     (iml = rtnl_dereference(*imlp)) != NULL;
1954	     imlp = &iml->next_rcu) {
1955		if (iml->multi.imr_multiaddr.s_addr != group)
1956			continue;
1957		if (ifindex) {
1958			if (iml->multi.imr_ifindex != ifindex)
1959				continue;
1960		} else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
1961				iml->multi.imr_address.s_addr)
1962			continue;
1963
1964		(void) ip_mc_leave_src(sk, iml, in_dev);
1965
1966		*imlp = iml->next_rcu;
1967
1968		ip_mc_dec_group(in_dev, group);
1969		rtnl_unlock();
1970		/* decrease mem now to avoid the memleak warning */
1971		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
1972		kfree_rcu(iml, rcu);
1973		return 0;
1974	}
1975out:
1976	rtnl_unlock();
1977	return ret;
1978}
1979EXPORT_SYMBOL(ip_mc_leave_group);
1980
1981int ip_mc_source(int add, int omode, struct sock *sk, struct
1982	ip_mreq_source *mreqs, int ifindex)
1983{
1984	int err;
1985	struct ip_mreqn imr;
1986	__be32 addr = mreqs->imr_multiaddr;
1987	struct ip_mc_socklist *pmc;
1988	struct in_device *in_dev = NULL;
1989	struct inet_sock *inet = inet_sk(sk);
1990	struct ip_sf_socklist *psl;
1991	struct net *net = sock_net(sk);
1992	int leavegroup = 0;
1993	int i, j, rv;
1994
1995	if (!ipv4_is_multicast(addr))
1996		return -EINVAL;
1997
1998	rtnl_lock();
1999
2000	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
2001	imr.imr_address.s_addr = mreqs->imr_interface;
2002	imr.imr_ifindex = ifindex;
2003	in_dev = ip_mc_find_dev(net, &imr);
2004
2005	if (!in_dev) {
2006		err = -ENODEV;
2007		goto done;
2008	}
2009	err = -EADDRNOTAVAIL;
2010
2011	for_each_pmc_rtnl(inet, pmc) {
2012		if ((pmc->multi.imr_multiaddr.s_addr ==
2013		     imr.imr_multiaddr.s_addr) &&
2014		    (pmc->multi.imr_ifindex == imr.imr_ifindex))
2015			break;
2016	}
2017	if (!pmc) {		/* must have a prior join */
2018		err = -EINVAL;
2019		goto done;
2020	}
2021	/* if a source filter was set, must be the same mode as before */
2022	if (pmc->sflist) {
2023		if (pmc->sfmode != omode) {
2024			err = -EINVAL;
2025			goto done;
2026		}
2027	} else if (pmc->sfmode != omode) {
2028		/* allow mode switches for empty-set filters */
2029		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
2030		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
2031			NULL, 0);
2032		pmc->sfmode = omode;
2033	}
2034
2035	psl = rtnl_dereference(pmc->sflist);
2036	if (!add) {
2037		if (!psl)
2038			goto done;	/* err = -EADDRNOTAVAIL */
2039		rv = !0;
2040		for (i = 0; i < psl->sl_count; i++) {
2041			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2042				sizeof(__be32));
2043			if (rv == 0)
2044				break;
2045		}
2046		if (rv)		/* source not found */
2047			goto done;	/* err = -EADDRNOTAVAIL */
2048
2049		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2050		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
2051			leavegroup = 1;
2052			goto done;
2053		}
2054
2055		/* update the interface filter */
2056		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2057			&mreqs->imr_sourceaddr, 1);
2058
2059		for (j = i+1; j < psl->sl_count; j++)
2060			psl->sl_addr[j-1] = psl->sl_addr[j];
2061		psl->sl_count--;
2062		err = 0;
2063		goto done;
2064	}
2065	/* else, add a new source to the filter */
2066
2067	if (psl && psl->sl_count >= sysctl_igmp_max_msf) {
2068		err = -ENOBUFS;
2069		goto done;
2070	}
2071	if (!psl || psl->sl_count == psl->sl_max) {
2072		struct ip_sf_socklist *newpsl;
2073		int count = IP_SFBLOCK;
2074
2075		if (psl)
2076			count += psl->sl_max;
2077		newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
2078		if (!newpsl) {
2079			err = -ENOBUFS;
2080			goto done;
2081		}
2082		newpsl->sl_max = count;
2083		newpsl->sl_count = count - IP_SFBLOCK;
2084		if (psl) {
2085			for (i = 0; i < psl->sl_count; i++)
2086				newpsl->sl_addr[i] = psl->sl_addr[i];
2087			/* decrease mem now to avoid the memleak warning */
2088			atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2089			kfree_rcu(psl, rcu);
2090		}
2091		rcu_assign_pointer(pmc->sflist, newpsl);
2092		psl = newpsl;
2093	}
2094	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
2095	for (i = 0; i < psl->sl_count; i++) {
2096		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2097			sizeof(__be32));
2098		if (rv == 0)
2099			break;
2100	}
2101	if (rv == 0)		/* address already there is an error */
2102		goto done;
2103	for (j = psl->sl_count-1; j >= i; j--)
2104		psl->sl_addr[j+1] = psl->sl_addr[j];
2105	psl->sl_addr[i] = mreqs->imr_sourceaddr;
2106	psl->sl_count++;
2107	err = 0;
2108	/* update the interface list */
2109	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2110		&mreqs->imr_sourceaddr, 1);
2111done:
2112	rtnl_unlock();
2113	if (leavegroup)
2114		return ip_mc_leave_group(sk, &imr);
2115	return err;
2116}
2117
2118int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2119{
2120	int err = 0;
2121	struct ip_mreqn	imr;
2122	__be32 addr = msf->imsf_multiaddr;
2123	struct ip_mc_socklist *pmc;
2124	struct in_device *in_dev;
2125	struct inet_sock *inet = inet_sk(sk);
2126	struct ip_sf_socklist *newpsl, *psl;
2127	struct net *net = sock_net(sk);
2128	int leavegroup = 0;
2129
2130	if (!ipv4_is_multicast(addr))
2131		return -EINVAL;
2132	if (msf->imsf_fmode != MCAST_INCLUDE &&
2133	    msf->imsf_fmode != MCAST_EXCLUDE)
2134		return -EINVAL;
2135
2136	rtnl_lock();
2137
2138	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2139	imr.imr_address.s_addr = msf->imsf_interface;
2140	imr.imr_ifindex = ifindex;
2141	in_dev = ip_mc_find_dev(net, &imr);
2142
2143	if (!in_dev) {
2144		err = -ENODEV;
2145		goto done;
2146	}
2147
2148	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2149	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2150		leavegroup = 1;
2151		goto done;
2152	}
2153
2154	for_each_pmc_rtnl(inet, pmc) {
2155		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2156		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2157			break;
2158	}
2159	if (!pmc) {		/* must have a prior join */
2160		err = -EINVAL;
2161		goto done;
2162	}
2163	if (msf->imsf_numsrc) {
2164		newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2165							   GFP_KERNEL);
2166		if (!newpsl) {
2167			err = -ENOBUFS;
2168			goto done;
2169		}
2170		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2171		memcpy(newpsl->sl_addr, msf->imsf_slist,
2172			msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2173		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2174			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2175		if (err) {
2176			sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2177			goto done;
2178		}
2179	} else {
2180		newpsl = NULL;
2181		(void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2182				     msf->imsf_fmode, 0, NULL, 0);
2183	}
2184	psl = rtnl_dereference(pmc->sflist);
2185	if (psl) {
2186		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2187			psl->sl_count, psl->sl_addr, 0);
2188		/* decrease mem now to avoid the memleak warning */
2189		atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2190		kfree_rcu(psl, rcu);
2191	} else
2192		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2193			0, NULL, 0);
2194	rcu_assign_pointer(pmc->sflist, newpsl);
2195	pmc->sfmode = msf->imsf_fmode;
2196	err = 0;
2197done:
2198	rtnl_unlock();
2199	if (leavegroup)
2200		err = ip_mc_leave_group(sk, &imr);
2201	return err;
2202}
2203
2204int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2205	struct ip_msfilter __user *optval, int __user *optlen)
2206{
2207	int err, len, count, copycount;
2208	struct ip_mreqn	imr;
2209	__be32 addr = msf->imsf_multiaddr;
2210	struct ip_mc_socklist *pmc;
2211	struct in_device *in_dev;
2212	struct inet_sock *inet = inet_sk(sk);
2213	struct ip_sf_socklist *psl;
2214	struct net *net = sock_net(sk);
2215
2216	if (!ipv4_is_multicast(addr))
2217		return -EINVAL;
2218
2219	rtnl_lock();
2220
2221	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2222	imr.imr_address.s_addr = msf->imsf_interface;
2223	imr.imr_ifindex = 0;
2224	in_dev = ip_mc_find_dev(net, &imr);
2225
2226	if (!in_dev) {
2227		err = -ENODEV;
2228		goto done;
2229	}
2230	err = -EADDRNOTAVAIL;
2231
2232	for_each_pmc_rtnl(inet, pmc) {
2233		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2234		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2235			break;
2236	}
2237	if (!pmc)		/* must have a prior join */
2238		goto done;
2239	msf->imsf_fmode = pmc->sfmode;
2240	psl = rtnl_dereference(pmc->sflist);
2241	rtnl_unlock();
2242	if (!psl) {
2243		len = 0;
2244		count = 0;
2245	} else {
2246		count = psl->sl_count;
2247	}
2248	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2249	len = copycount * sizeof(psl->sl_addr[0]);
2250	msf->imsf_numsrc = count;
2251	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2252	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2253		return -EFAULT;
2254	}
2255	if (len &&
2256	    copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2257		return -EFAULT;
2258	return 0;
2259done:
2260	rtnl_unlock();
2261	return err;
2262}
2263
2264int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2265	struct group_filter __user *optval, int __user *optlen)
2266{
2267	int err, i, count, copycount;
2268	struct sockaddr_in *psin;
2269	__be32 addr;
2270	struct ip_mc_socklist *pmc;
2271	struct inet_sock *inet = inet_sk(sk);
2272	struct ip_sf_socklist *psl;
2273
2274	psin = (struct sockaddr_in *)&gsf->gf_group;
2275	if (psin->sin_family != AF_INET)
2276		return -EINVAL;
2277	addr = psin->sin_addr.s_addr;
2278	if (!ipv4_is_multicast(addr))
2279		return -EINVAL;
2280
2281	rtnl_lock();
2282
2283	err = -EADDRNOTAVAIL;
2284
2285	for_each_pmc_rtnl(inet, pmc) {
2286		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2287		    pmc->multi.imr_ifindex == gsf->gf_interface)
2288			break;
2289	}
2290	if (!pmc)		/* must have a prior join */
2291		goto done;
2292	gsf->gf_fmode = pmc->sfmode;
2293	psl = rtnl_dereference(pmc->sflist);
2294	rtnl_unlock();
2295	count = psl ? psl->sl_count : 0;
2296	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2297	gsf->gf_numsrc = count;
2298	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2299	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2300		return -EFAULT;
2301	}
2302	for (i = 0; i < copycount; i++) {
2303		struct sockaddr_storage ss;
2304
2305		psin = (struct sockaddr_in *)&ss;
2306		memset(&ss, 0, sizeof(ss));
2307		psin->sin_family = AF_INET;
2308		psin->sin_addr.s_addr = psl->sl_addr[i];
2309		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2310			return -EFAULT;
2311	}
2312	return 0;
2313done:
2314	rtnl_unlock();
2315	return err;
2316}
2317
2318/*
2319 * check if a multicast source filter allows delivery for a given <src,dst,intf>
2320 */
2321int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif)
2322{
2323	struct inet_sock *inet = inet_sk(sk);
2324	struct ip_mc_socklist *pmc;
2325	struct ip_sf_socklist *psl;
2326	int i;
2327	int ret;
2328
2329	ret = 1;
2330	if (!ipv4_is_multicast(loc_addr))
2331		goto out;
2332
2333	rcu_read_lock();
2334	for_each_pmc_rcu(inet, pmc) {
2335		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2336		    pmc->multi.imr_ifindex == dif)
2337			break;
2338	}
2339	ret = inet->mc_all;
2340	if (!pmc)
2341		goto unlock;
2342	psl = rcu_dereference(pmc->sflist);
2343	ret = (pmc->sfmode == MCAST_EXCLUDE);
2344	if (!psl)
2345		goto unlock;
2346
2347	for (i = 0; i < psl->sl_count; i++) {
2348		if (psl->sl_addr[i] == rmt_addr)
2349			break;
2350	}
2351	ret = 0;
2352	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2353		goto unlock;
2354	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2355		goto unlock;
2356	ret = 1;
2357unlock:
2358	rcu_read_unlock();
2359out:
2360	return ret;
2361}
2362
2363/*
2364 *	A socket is closing.
2365 */
2366
2367void ip_mc_drop_socket(struct sock *sk)
2368{
2369	struct inet_sock *inet = inet_sk(sk);
2370	struct ip_mc_socklist *iml;
2371	struct net *net = sock_net(sk);
2372
2373	if (inet->mc_list == NULL)
2374		return;
2375
2376	rtnl_lock();
2377	while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2378		struct in_device *in_dev;
2379
2380		inet->mc_list = iml->next_rcu;
2381		in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2382		(void) ip_mc_leave_src(sk, iml, in_dev);
2383		if (in_dev != NULL)
2384			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2385		/* decrease mem now to avoid the memleak warning */
2386		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2387		kfree_rcu(iml, rcu);
2388	}
2389	rtnl_unlock();
2390}
2391
2392/* called with rcu_read_lock() */
2393int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u16 proto)
2394{
2395	struct ip_mc_list *im;
2396	struct ip_mc_list __rcu **mc_hash;
2397	struct ip_sf_list *psf;
2398	int rv = 0;
2399
2400	mc_hash = rcu_dereference(in_dev->mc_hash);
2401	if (mc_hash) {
2402		u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
2403
2404		for (im = rcu_dereference(mc_hash[hash]);
2405		     im != NULL;
2406		     im = rcu_dereference(im->next_hash)) {
2407			if (im->multiaddr == mc_addr)
2408				break;
2409		}
2410	} else {
2411		for_each_pmc_rcu(in_dev, im) {
2412			if (im->multiaddr == mc_addr)
2413				break;
2414		}
2415	}
2416	if (im && proto == IPPROTO_IGMP) {
2417		rv = 1;
2418	} else if (im) {
2419		if (src_addr) {
2420			for (psf = im->sources; psf; psf = psf->sf_next) {
2421				if (psf->sf_inaddr == src_addr)
2422					break;
2423			}
2424			if (psf)
2425				rv = psf->sf_count[MCAST_INCLUDE] ||
2426					psf->sf_count[MCAST_EXCLUDE] !=
2427					im->sfcount[MCAST_EXCLUDE];
2428			else
2429				rv = im->sfcount[MCAST_EXCLUDE] != 0;
2430		} else
2431			rv = 1; /* unspecified source; tentatively allow */
2432	}
2433	return rv;
2434}
2435
2436#if defined(CONFIG_PROC_FS)
2437struct igmp_mc_iter_state {
2438	struct seq_net_private p;
2439	struct net_device *dev;
2440	struct in_device *in_dev;
2441};
2442
2443#define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2444
2445static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2446{
2447	struct net *net = seq_file_net(seq);
2448	struct ip_mc_list *im = NULL;
2449	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2450
2451	state->in_dev = NULL;
2452	for_each_netdev_rcu(net, state->dev) {
2453		struct in_device *in_dev;
2454
2455		in_dev = __in_dev_get_rcu(state->dev);
2456		if (!in_dev)
2457			continue;
2458		im = rcu_dereference(in_dev->mc_list);
2459		if (im) {
2460			state->in_dev = in_dev;
2461			break;
2462		}
2463	}
2464	return im;
2465}
2466
2467static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2468{
2469	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2470
2471	im = rcu_dereference(im->next_rcu);
2472	while (!im) {
2473		state->dev = next_net_device_rcu(state->dev);
2474		if (!state->dev) {
2475			state->in_dev = NULL;
2476			break;
2477		}
2478		state->in_dev = __in_dev_get_rcu(state->dev);
2479		if (!state->in_dev)
2480			continue;
2481		im = rcu_dereference(state->in_dev->mc_list);
2482	}
2483	return im;
2484}
2485
2486static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2487{
2488	struct ip_mc_list *im = igmp_mc_get_first(seq);
2489	if (im)
2490		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2491			--pos;
2492	return pos ? NULL : im;
2493}
2494
2495static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2496	__acquires(rcu)
2497{
2498	rcu_read_lock();
2499	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2500}
2501
2502static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2503{
2504	struct ip_mc_list *im;
2505	if (v == SEQ_START_TOKEN)
2506		im = igmp_mc_get_first(seq);
2507	else
2508		im = igmp_mc_get_next(seq, v);
2509	++*pos;
2510	return im;
2511}
2512
2513static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2514	__releases(rcu)
2515{
2516	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2517
2518	state->in_dev = NULL;
2519	state->dev = NULL;
2520	rcu_read_unlock();
2521}
2522
2523static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2524{
2525	if (v == SEQ_START_TOKEN)
2526		seq_puts(seq,
2527			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2528	else {
2529		struct ip_mc_list *im = (struct ip_mc_list *)v;
2530		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2531		char   *querier;
2532		long delta;
2533
2534#ifdef CONFIG_IP_MULTICAST
2535		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2536			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2537			  "V3";
2538#else
2539		querier = "NONE";
2540#endif
2541
2542		if (rcu_dereference(state->in_dev->mc_list) == im) {
2543			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2544				   state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2545		}
2546
2547		delta = im->timer.expires - jiffies;
2548		seq_printf(seq,
2549			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2550			   im->multiaddr, im->users,
2551			   im->tm_running,
2552			   im->tm_running ? jiffies_delta_to_clock_t(delta) : 0,
2553			   im->reporter);
2554	}
2555	return 0;
2556}
2557
2558static const struct seq_operations igmp_mc_seq_ops = {
2559	.start	=	igmp_mc_seq_start,
2560	.next	=	igmp_mc_seq_next,
2561	.stop	=	igmp_mc_seq_stop,
2562	.show	=	igmp_mc_seq_show,
2563};
2564
2565static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2566{
2567	return seq_open_net(inode, file, &igmp_mc_seq_ops,
2568			sizeof(struct igmp_mc_iter_state));
2569}
2570
2571static const struct file_operations igmp_mc_seq_fops = {
2572	.owner		=	THIS_MODULE,
2573	.open		=	igmp_mc_seq_open,
2574	.read		=	seq_read,
2575	.llseek		=	seq_lseek,
2576	.release	=	seq_release_net,
2577};
2578
2579struct igmp_mcf_iter_state {
2580	struct seq_net_private p;
2581	struct net_device *dev;
2582	struct in_device *idev;
2583	struct ip_mc_list *im;
2584};
2585
2586#define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2587
2588static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2589{
2590	struct net *net = seq_file_net(seq);
2591	struct ip_sf_list *psf = NULL;
2592	struct ip_mc_list *im = NULL;
2593	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2594
2595	state->idev = NULL;
2596	state->im = NULL;
2597	for_each_netdev_rcu(net, state->dev) {
2598		struct in_device *idev;
2599		idev = __in_dev_get_rcu(state->dev);
2600		if (unlikely(idev == NULL))
2601			continue;
2602		im = rcu_dereference(idev->mc_list);
2603		if (likely(im != NULL)) {
2604			spin_lock_bh(&im->lock);
2605			psf = im->sources;
2606			if (likely(psf != NULL)) {
2607				state->im = im;
2608				state->idev = idev;
2609				break;
2610			}
2611			spin_unlock_bh(&im->lock);
2612		}
2613	}
2614	return psf;
2615}
2616
2617static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2618{
2619	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2620
2621	psf = psf->sf_next;
2622	while (!psf) {
2623		spin_unlock_bh(&state->im->lock);
2624		state->im = state->im->next;
2625		while (!state->im) {
2626			state->dev = next_net_device_rcu(state->dev);
2627			if (!state->dev) {
2628				state->idev = NULL;
2629				goto out;
2630			}
2631			state->idev = __in_dev_get_rcu(state->dev);
2632			if (!state->idev)
2633				continue;
2634			state->im = rcu_dereference(state->idev->mc_list);
2635		}
2636		if (!state->im)
2637			break;
2638		spin_lock_bh(&state->im->lock);
2639		psf = state->im->sources;
2640	}
2641out:
2642	return psf;
2643}
2644
2645static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2646{
2647	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2648	if (psf)
2649		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2650			--pos;
2651	return pos ? NULL : psf;
2652}
2653
2654static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2655	__acquires(rcu)
2656{
2657	rcu_read_lock();
2658	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2659}
2660
2661static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2662{
2663	struct ip_sf_list *psf;
2664	if (v == SEQ_START_TOKEN)
2665		psf = igmp_mcf_get_first(seq);
2666	else
2667		psf = igmp_mcf_get_next(seq, v);
2668	++*pos;
2669	return psf;
2670}
2671
2672static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2673	__releases(rcu)
2674{
2675	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2676	if (likely(state->im != NULL)) {
2677		spin_unlock_bh(&state->im->lock);
2678		state->im = NULL;
2679	}
2680	state->idev = NULL;
2681	state->dev = NULL;
2682	rcu_read_unlock();
2683}
2684
2685static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2686{
2687	struct ip_sf_list *psf = (struct ip_sf_list *)v;
2688	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2689
2690	if (v == SEQ_START_TOKEN) {
2691		seq_printf(seq,
2692			   "%3s %6s "
2693			   "%10s %10s %6s %6s\n", "Idx",
2694			   "Device", "MCA",
2695			   "SRC", "INC", "EXC");
2696	} else {
2697		seq_printf(seq,
2698			   "%3d %6.6s 0x%08x "
2699			   "0x%08x %6lu %6lu\n",
2700			   state->dev->ifindex, state->dev->name,
2701			   ntohl(state->im->multiaddr),
2702			   ntohl(psf->sf_inaddr),
2703			   psf->sf_count[MCAST_INCLUDE],
2704			   psf->sf_count[MCAST_EXCLUDE]);
2705	}
2706	return 0;
2707}
2708
2709static const struct seq_operations igmp_mcf_seq_ops = {
2710	.start	=	igmp_mcf_seq_start,
2711	.next	=	igmp_mcf_seq_next,
2712	.stop	=	igmp_mcf_seq_stop,
2713	.show	=	igmp_mcf_seq_show,
2714};
2715
2716static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2717{
2718	return seq_open_net(inode, file, &igmp_mcf_seq_ops,
2719			sizeof(struct igmp_mcf_iter_state));
2720}
2721
2722static const struct file_operations igmp_mcf_seq_fops = {
2723	.owner		=	THIS_MODULE,
2724	.open		=	igmp_mcf_seq_open,
2725	.read		=	seq_read,
2726	.llseek		=	seq_lseek,
2727	.release	=	seq_release_net,
2728};
2729
2730static int __net_init igmp_net_init(struct net *net)
2731{
2732	struct proc_dir_entry *pde;
2733
2734	pde = proc_create("igmp", S_IRUGO, net->proc_net, &igmp_mc_seq_fops);
2735	if (!pde)
2736		goto out_igmp;
2737	pde = proc_create("mcfilter", S_IRUGO, net->proc_net,
2738			  &igmp_mcf_seq_fops);
2739	if (!pde)
2740		goto out_mcfilter;
2741	return 0;
2742
2743out_mcfilter:
2744	remove_proc_entry("igmp", net->proc_net);
2745out_igmp:
2746	return -ENOMEM;
2747}
2748
2749static void __net_exit igmp_net_exit(struct net *net)
2750{
2751	remove_proc_entry("mcfilter", net->proc_net);
2752	remove_proc_entry("igmp", net->proc_net);
2753}
2754
2755static struct pernet_operations igmp_net_ops = {
2756	.init = igmp_net_init,
2757	.exit = igmp_net_exit,
2758};
2759#endif
2760
2761static int igmp_netdev_event(struct notifier_block *this,
2762			     unsigned long event, void *ptr)
2763{
2764	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2765	struct in_device *in_dev;
2766
2767	switch (event) {
2768	case NETDEV_RESEND_IGMP:
2769		in_dev = __in_dev_get_rtnl(dev);
2770		if (in_dev)
2771			ip_mc_rejoin_groups(in_dev);
2772		break;
2773	default:
2774		break;
2775	}
2776	return NOTIFY_DONE;
2777}
2778
2779static struct notifier_block igmp_notifier = {
2780	.notifier_call = igmp_netdev_event,
2781};
2782
2783int __init igmp_mc_init(void)
2784{
2785#if defined(CONFIG_PROC_FS)
2786	int err;
2787
2788	err = register_pernet_subsys(&igmp_net_ops);
2789	if (err)
2790		return err;
2791	err = register_netdevice_notifier(&igmp_notifier);
2792	if (err)
2793		goto reg_notif_fail;
2794	return 0;
2795
2796reg_notif_fail:
2797	unregister_pernet_subsys(&igmp_net_ops);
2798	return err;
2799#else
2800	return register_netdevice_notifier(&igmp_notifier);
2801#endif
2802}
2803