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v5.14.15
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *	Linux NET3:	Internet Group Management Protocol  [IGMP]
   4 *
   5 *	This code implements the IGMP protocol as defined in RFC1112. There has
   6 *	been a further revision of this protocol since which is now supported.
   7 *
   8 *	If you have trouble with this module be careful what gcc you have used,
   9 *	the older version didn't come out right using gcc 2.5.8, the newer one
  10 *	seems to fall out with gcc 2.6.2.
  11 *
  12 *	Authors:
  13 *		Alan Cox <alan@lxorguk.ukuu.org.uk>
  14 *
 
 
 
 
 
  15 *	Fixes:
  16 *
  17 *		Alan Cox	:	Added lots of __inline__ to optimise
  18 *					the memory usage of all the tiny little
  19 *					functions.
  20 *		Alan Cox	:	Dumped the header building experiment.
  21 *		Alan Cox	:	Minor tweaks ready for multicast routing
  22 *					and extended IGMP protocol.
  23 *		Alan Cox	:	Removed a load of inline directives. Gcc 2.5.8
  24 *					writes utterly bogus code otherwise (sigh)
  25 *					fixed IGMP loopback to behave in the manner
  26 *					desired by mrouted, fixed the fact it has been
  27 *					broken since 1.3.6 and cleaned up a few minor
  28 *					points.
  29 *
  30 *		Chih-Jen Chang	:	Tried to revise IGMP to Version 2
  31 *		Tsu-Sheng Tsao		E-mail: chihjenc@scf.usc.edu and tsusheng@scf.usc.edu
  32 *					The enhancements are mainly based on Steve Deering's
  33 * 					ipmulti-3.5 source code.
  34 *		Chih-Jen Chang	:	Added the igmp_get_mrouter_info and
  35 *		Tsu-Sheng Tsao		igmp_set_mrouter_info to keep track of
  36 *					the mrouted version on that device.
  37 *		Chih-Jen Chang	:	Added the max_resp_time parameter to
  38 *		Tsu-Sheng Tsao		igmp_heard_query(). Using this parameter
  39 *					to identify the multicast router version
  40 *					and do what the IGMP version 2 specified.
  41 *		Chih-Jen Chang	:	Added a timer to revert to IGMP V2 router
  42 *		Tsu-Sheng Tsao		if the specified time expired.
  43 *		Alan Cox	:	Stop IGMP from 0.0.0.0 being accepted.
  44 *		Alan Cox	:	Use GFP_ATOMIC in the right places.
  45 *		Christian Daudt :	igmp timer wasn't set for local group
  46 *					memberships but was being deleted,
  47 *					which caused a "del_timer() called
  48 *					from %p with timer not initialized\n"
  49 *					message (960131).
  50 *		Christian Daudt :	removed del_timer from
  51 *					igmp_timer_expire function (960205).
  52 *             Christian Daudt :       igmp_heard_report now only calls
  53 *                                     igmp_timer_expire if tm->running is
  54 *                                     true (960216).
  55 *		Malcolm Beattie :	ttl comparison wrong in igmp_rcv made
  56 *					igmp_heard_query never trigger. Expiry
  57 *					miscalculation fixed in igmp_heard_query
  58 *					and random() made to return unsigned to
  59 *					prevent negative expiry times.
  60 *		Alexey Kuznetsov:	Wrong group leaving behaviour, backport
  61 *					fix from pending 2.1.x patches.
  62 *		Alan Cox:		Forget to enable FDDI support earlier.
  63 *		Alexey Kuznetsov:	Fixed leaving groups on device down.
  64 *		Alexey Kuznetsov:	Accordance to igmp-v2-06 draft.
  65 *		David L Stevens:	IGMPv3 support, with help from
  66 *					Vinay Kulkarni
  67 */
  68
  69#include <linux/module.h>
  70#include <linux/slab.h>
  71#include <linux/uaccess.h>
  72#include <linux/types.h>
  73#include <linux/kernel.h>
  74#include <linux/jiffies.h>
  75#include <linux/string.h>
  76#include <linux/socket.h>
  77#include <linux/sockios.h>
  78#include <linux/in.h>
  79#include <linux/inet.h>
  80#include <linux/netdevice.h>
  81#include <linux/skbuff.h>
  82#include <linux/inetdevice.h>
  83#include <linux/igmp.h>
  84#include <linux/if_arp.h>
  85#include <linux/rtnetlink.h>
  86#include <linux/times.h>
  87#include <linux/pkt_sched.h>
  88#include <linux/byteorder/generic.h>
  89
  90#include <net/net_namespace.h>
  91#include <net/arp.h>
  92#include <net/ip.h>
  93#include <net/protocol.h>
  94#include <net/route.h>
  95#include <net/sock.h>
  96#include <net/checksum.h>
  97#include <net/inet_common.h>
  98#include <linux/netfilter_ipv4.h>
  99#ifdef CONFIG_IP_MROUTE
 100#include <linux/mroute.h>
 101#endif
 102#ifdef CONFIG_PROC_FS
 103#include <linux/proc_fs.h>
 104#include <linux/seq_file.h>
 105#endif
 106
 107#ifdef CONFIG_IP_MULTICAST
 108/* Parameter names and values are taken from igmp-v2-06 draft */
 109
 110#define IGMP_QUERY_INTERVAL			(125*HZ)
 
 
 
 111#define IGMP_QUERY_RESPONSE_INTERVAL		(10*HZ)
 
 
 112
 113#define IGMP_INITIAL_REPORT_DELAY		(1)
 114
 115/* IGMP_INITIAL_REPORT_DELAY is not from IGMP specs!
 116 * IGMP specs require to report membership immediately after
 117 * joining a group, but we delay the first report by a
 118 * small interval. It seems more natural and still does not
 119 * contradict to specs provided this delay is small enough.
 120 */
 121
 122#define IGMP_V1_SEEN(in_dev) \
 123	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \
 124	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \
 125	 ((in_dev)->mr_v1_seen && \
 126	  time_before(jiffies, (in_dev)->mr_v1_seen)))
 127#define IGMP_V2_SEEN(in_dev) \
 128	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \
 129	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \
 130	 ((in_dev)->mr_v2_seen && \
 131	  time_before(jiffies, (in_dev)->mr_v2_seen)))
 132
 133static int unsolicited_report_interval(struct in_device *in_dev)
 134{
 135	int interval_ms, interval_jiffies;
 136
 137	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 138		interval_ms = IN_DEV_CONF_GET(
 139			in_dev,
 140			IGMPV2_UNSOLICITED_REPORT_INTERVAL);
 141	else /* v3 */
 142		interval_ms = IN_DEV_CONF_GET(
 143			in_dev,
 144			IGMPV3_UNSOLICITED_REPORT_INTERVAL);
 145
 146	interval_jiffies = msecs_to_jiffies(interval_ms);
 147
 148	/* _timer functions can't handle a delay of 0 jiffies so ensure
 149	 *  we always return a positive value.
 150	 */
 151	if (interval_jiffies <= 0)
 152		interval_jiffies = 1;
 153	return interval_jiffies;
 154}
 155
 156static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im,
 157			      gfp_t gfp);
 158static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im);
 159static void igmpv3_clear_delrec(struct in_device *in_dev);
 160static int sf_setstate(struct ip_mc_list *pmc);
 161static void sf_markstate(struct ip_mc_list *pmc);
 162#endif
 163static void ip_mc_clear_src(struct ip_mc_list *pmc);
 164static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
 165			 int sfcount, __be32 *psfsrc, int delta);
 166
 167static void ip_ma_put(struct ip_mc_list *im)
 168{
 169	if (refcount_dec_and_test(&im->refcnt)) {
 170		in_dev_put(im->interface);
 171		kfree_rcu(im, rcu);
 172	}
 173}
 174
 175#define for_each_pmc_rcu(in_dev, pmc)				\
 176	for (pmc = rcu_dereference(in_dev->mc_list);		\
 177	     pmc != NULL;					\
 178	     pmc = rcu_dereference(pmc->next_rcu))
 179
 180#define for_each_pmc_rtnl(in_dev, pmc)				\
 181	for (pmc = rtnl_dereference(in_dev->mc_list);		\
 182	     pmc != NULL;					\
 183	     pmc = rtnl_dereference(pmc->next_rcu))
 184
 185static void ip_sf_list_clear_all(struct ip_sf_list *psf)
 186{
 187	struct ip_sf_list *next;
 188
 189	while (psf) {
 190		next = psf->sf_next;
 191		kfree(psf);
 192		psf = next;
 193	}
 194}
 195
 196#ifdef CONFIG_IP_MULTICAST
 197
 198/*
 199 *	Timer management
 200 */
 201
 202static void igmp_stop_timer(struct ip_mc_list *im)
 203{
 204	spin_lock_bh(&im->lock);
 205	if (del_timer(&im->timer))
 206		refcount_dec(&im->refcnt);
 207	im->tm_running = 0;
 208	im->reporter = 0;
 209	im->unsolicit_count = 0;
 210	spin_unlock_bh(&im->lock);
 211}
 212
 213/* It must be called with locked im->lock */
 214static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
 215{
 216	int tv = prandom_u32() % max_delay;
 217
 218	im->tm_running = 1;
 219	if (!mod_timer(&im->timer, jiffies+tv+2))
 220		refcount_inc(&im->refcnt);
 221}
 222
 223static void igmp_gq_start_timer(struct in_device *in_dev)
 224{
 225	int tv = prandom_u32() % in_dev->mr_maxdelay;
 226	unsigned long exp = jiffies + tv + 2;
 227
 228	if (in_dev->mr_gq_running &&
 229	    time_after_eq(exp, (in_dev->mr_gq_timer).expires))
 230		return;
 231
 232	in_dev->mr_gq_running = 1;
 233	if (!mod_timer(&in_dev->mr_gq_timer, exp))
 234		in_dev_hold(in_dev);
 235}
 236
 237static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
 238{
 239	int tv = prandom_u32() % delay;
 240
 241	if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
 242		in_dev_hold(in_dev);
 243}
 244
 245static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
 246{
 247	spin_lock_bh(&im->lock);
 248	im->unsolicit_count = 0;
 249	if (del_timer(&im->timer)) {
 250		if ((long)(im->timer.expires-jiffies) < max_delay) {
 251			add_timer(&im->timer);
 252			im->tm_running = 1;
 253			spin_unlock_bh(&im->lock);
 254			return;
 255		}
 256		refcount_dec(&im->refcnt);
 257	}
 258	igmp_start_timer(im, max_delay);
 259	spin_unlock_bh(&im->lock);
 260}
 261
 262
 263/*
 264 *	Send an IGMP report.
 265 */
 266
 267#define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
 268
 269
 270static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
 271	int gdeleted, int sdeleted)
 272{
 273	switch (type) {
 274	case IGMPV3_MODE_IS_INCLUDE:
 275	case IGMPV3_MODE_IS_EXCLUDE:
 276		if (gdeleted || sdeleted)
 277			return 0;
 278		if (!(pmc->gsquery && !psf->sf_gsresp)) {
 279			if (pmc->sfmode == MCAST_INCLUDE)
 280				return 1;
 281			/* don't include if this source is excluded
 282			 * in all filters
 283			 */
 284			if (psf->sf_count[MCAST_INCLUDE])
 285				return type == IGMPV3_MODE_IS_INCLUDE;
 286			return pmc->sfcount[MCAST_EXCLUDE] ==
 287				psf->sf_count[MCAST_EXCLUDE];
 288		}
 289		return 0;
 290	case IGMPV3_CHANGE_TO_INCLUDE:
 291		if (gdeleted || sdeleted)
 292			return 0;
 293		return psf->sf_count[MCAST_INCLUDE] != 0;
 294	case IGMPV3_CHANGE_TO_EXCLUDE:
 295		if (gdeleted || sdeleted)
 296			return 0;
 297		if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
 298		    psf->sf_count[MCAST_INCLUDE])
 299			return 0;
 300		return pmc->sfcount[MCAST_EXCLUDE] ==
 301			psf->sf_count[MCAST_EXCLUDE];
 302	case IGMPV3_ALLOW_NEW_SOURCES:
 303		if (gdeleted || !psf->sf_crcount)
 304			return 0;
 305		return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
 306	case IGMPV3_BLOCK_OLD_SOURCES:
 307		if (pmc->sfmode == MCAST_INCLUDE)
 308			return gdeleted || (psf->sf_crcount && sdeleted);
 309		return psf->sf_crcount && !gdeleted && !sdeleted;
 310	}
 311	return 0;
 312}
 313
 314static int
 315igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
 316{
 317	struct ip_sf_list *psf;
 318	int scount = 0;
 319
 320	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 321		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
 322			continue;
 323		scount++;
 324	}
 325	return scount;
 326}
 327
 328/* source address selection per RFC 3376 section 4.2.13 */
 329static __be32 igmpv3_get_srcaddr(struct net_device *dev,
 330				 const struct flowi4 *fl4)
 331{
 332	struct in_device *in_dev = __in_dev_get_rcu(dev);
 333	const struct in_ifaddr *ifa;
 334
 335	if (!in_dev)
 336		return htonl(INADDR_ANY);
 337
 338	in_dev_for_each_ifa_rcu(ifa, in_dev) {
 339		if (fl4->saddr == ifa->ifa_local)
 340			return fl4->saddr;
 341	}
 342
 343	return htonl(INADDR_ANY);
 344}
 345
 346static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
 347{
 348	struct sk_buff *skb;
 349	struct rtable *rt;
 350	struct iphdr *pip;
 351	struct igmpv3_report *pig;
 352	struct net *net = dev_net(dev);
 353	struct flowi4 fl4;
 354	int hlen = LL_RESERVED_SPACE(dev);
 355	int tlen = dev->needed_tailroom;
 356	unsigned int size = mtu;
 357
 358	while (1) {
 359		skb = alloc_skb(size + hlen + tlen,
 360				GFP_ATOMIC | __GFP_NOWARN);
 361		if (skb)
 362			break;
 363		size >>= 1;
 364		if (size < 256)
 365			return NULL;
 366	}
 367	skb->priority = TC_PRIO_CONTROL;
 368
 369	rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0,
 370				   0, 0,
 371				   IPPROTO_IGMP, 0, dev->ifindex);
 372	if (IS_ERR(rt)) {
 373		kfree_skb(skb);
 374		return NULL;
 375	}
 376
 377	skb_dst_set(skb, &rt->dst);
 378	skb->dev = dev;
 379
 380	skb_reserve(skb, hlen);
 381	skb_tailroom_reserve(skb, mtu, tlen);
 382
 383	skb_reset_network_header(skb);
 384	pip = ip_hdr(skb);
 385	skb_put(skb, sizeof(struct iphdr) + 4);
 386
 387	pip->version  = 4;
 388	pip->ihl      = (sizeof(struct iphdr)+4)>>2;
 389	pip->tos      = 0xc0;
 390	pip->frag_off = htons(IP_DF);
 391	pip->ttl      = 1;
 392	pip->daddr    = fl4.daddr;
 393
 394	rcu_read_lock();
 395	pip->saddr    = igmpv3_get_srcaddr(dev, &fl4);
 396	rcu_read_unlock();
 397
 398	pip->protocol = IPPROTO_IGMP;
 399	pip->tot_len  = 0;	/* filled in later */
 400	ip_select_ident(net, skb, NULL);
 401	((u8 *)&pip[1])[0] = IPOPT_RA;
 402	((u8 *)&pip[1])[1] = 4;
 403	((u8 *)&pip[1])[2] = 0;
 404	((u8 *)&pip[1])[3] = 0;
 405
 406	skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
 407	skb_put(skb, sizeof(*pig));
 408	pig = igmpv3_report_hdr(skb);
 409	pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
 410	pig->resv1 = 0;
 411	pig->csum = 0;
 412	pig->resv2 = 0;
 413	pig->ngrec = 0;
 414	return skb;
 415}
 416
 417static int igmpv3_sendpack(struct sk_buff *skb)
 418{
 419	struct igmphdr *pig = igmp_hdr(skb);
 420	const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
 421
 422	pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
 423
 424	return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
 425}
 426
 427static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
 428{
 429	return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
 430}
 431
 432static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
 433	int type, struct igmpv3_grec **ppgr, unsigned int mtu)
 434{
 435	struct net_device *dev = pmc->interface->dev;
 436	struct igmpv3_report *pih;
 437	struct igmpv3_grec *pgr;
 438
 439	if (!skb) {
 440		skb = igmpv3_newpack(dev, mtu);
 441		if (!skb)
 442			return NULL;
 443	}
 444	pgr = skb_put(skb, sizeof(struct igmpv3_grec));
 445	pgr->grec_type = type;
 446	pgr->grec_auxwords = 0;
 447	pgr->grec_nsrcs = 0;
 448	pgr->grec_mca = pmc->multiaddr;
 449	pih = igmpv3_report_hdr(skb);
 450	pih->ngrec = htons(ntohs(pih->ngrec)+1);
 451	*ppgr = pgr;
 452	return skb;
 453}
 454
 455#define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
 456
 457static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
 458	int type, int gdeleted, int sdeleted)
 459{
 460	struct net_device *dev = pmc->interface->dev;
 461	struct net *net = dev_net(dev);
 462	struct igmpv3_report *pih;
 463	struct igmpv3_grec *pgr = NULL;
 464	struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
 465	int scount, stotal, first, isquery, truncate;
 466	unsigned int mtu;
 467
 468	if (pmc->multiaddr == IGMP_ALL_HOSTS)
 469		return skb;
 470	if (ipv4_is_local_multicast(pmc->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
 471		return skb;
 472
 473	mtu = READ_ONCE(dev->mtu);
 474	if (mtu < IPV4_MIN_MTU)
 475		return skb;
 476
 477	isquery = type == IGMPV3_MODE_IS_INCLUDE ||
 478		  type == IGMPV3_MODE_IS_EXCLUDE;
 479	truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
 480		    type == IGMPV3_CHANGE_TO_EXCLUDE;
 481
 482	stotal = scount = 0;
 483
 484	psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
 485
 486	if (!*psf_list)
 487		goto empty_source;
 488
 489	pih = skb ? igmpv3_report_hdr(skb) : NULL;
 490
 491	/* EX and TO_EX get a fresh packet, if needed */
 492	if (truncate) {
 493		if (pih && pih->ngrec &&
 494		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
 495			if (skb)
 496				igmpv3_sendpack(skb);
 497			skb = igmpv3_newpack(dev, mtu);
 498		}
 499	}
 500	first = 1;
 501	psf_prev = NULL;
 502	for (psf = *psf_list; psf; psf = psf_next) {
 503		__be32 *psrc;
 504
 505		psf_next = psf->sf_next;
 506
 507		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
 508			psf_prev = psf;
 509			continue;
 510		}
 511
 512		/* Based on RFC3376 5.1. Should not send source-list change
 513		 * records when there is a filter mode change.
 514		 */
 515		if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) ||
 516		     (!gdeleted && pmc->crcount)) &&
 517		    (type == IGMPV3_ALLOW_NEW_SOURCES ||
 518		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount)
 519			goto decrease_sf_crcount;
 520
 521		/* clear marks on query responses */
 522		if (isquery)
 523			psf->sf_gsresp = 0;
 524
 525		if (AVAILABLE(skb) < sizeof(__be32) +
 526		    first*sizeof(struct igmpv3_grec)) {
 527			if (truncate && !first)
 528				break;	 /* truncate these */
 529			if (pgr)
 530				pgr->grec_nsrcs = htons(scount);
 531			if (skb)
 532				igmpv3_sendpack(skb);
 533			skb = igmpv3_newpack(dev, mtu);
 534			first = 1;
 535			scount = 0;
 536		}
 537		if (first) {
 538			skb = add_grhead(skb, pmc, type, &pgr, mtu);
 539			first = 0;
 540		}
 541		if (!skb)
 542			return NULL;
 543		psrc = skb_put(skb, sizeof(__be32));
 544		*psrc = psf->sf_inaddr;
 545		scount++; stotal++;
 546		if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
 547		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
 548decrease_sf_crcount:
 549			psf->sf_crcount--;
 550			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
 551				if (psf_prev)
 552					psf_prev->sf_next = psf->sf_next;
 553				else
 554					*psf_list = psf->sf_next;
 555				kfree(psf);
 556				continue;
 557			}
 558		}
 559		psf_prev = psf;
 560	}
 561
 562empty_source:
 563	if (!stotal) {
 564		if (type == IGMPV3_ALLOW_NEW_SOURCES ||
 565		    type == IGMPV3_BLOCK_OLD_SOURCES)
 566			return skb;
 567		if (pmc->crcount || isquery) {
 568			/* make sure we have room for group header */
 569			if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) {
 570				igmpv3_sendpack(skb);
 571				skb = NULL; /* add_grhead will get a new one */
 572			}
 573			skb = add_grhead(skb, pmc, type, &pgr, mtu);
 574		}
 575	}
 576	if (pgr)
 577		pgr->grec_nsrcs = htons(scount);
 578
 579	if (isquery)
 580		pmc->gsquery = 0;	/* clear query state on report */
 581	return skb;
 582}
 583
 584static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
 585{
 586	struct sk_buff *skb = NULL;
 587	struct net *net = dev_net(in_dev->dev);
 588	int type;
 589
 590	if (!pmc) {
 591		rcu_read_lock();
 592		for_each_pmc_rcu(in_dev, pmc) {
 593			if (pmc->multiaddr == IGMP_ALL_HOSTS)
 594				continue;
 595			if (ipv4_is_local_multicast(pmc->multiaddr) &&
 596			     !net->ipv4.sysctl_igmp_llm_reports)
 597				continue;
 598			spin_lock_bh(&pmc->lock);
 599			if (pmc->sfcount[MCAST_EXCLUDE])
 600				type = IGMPV3_MODE_IS_EXCLUDE;
 601			else
 602				type = IGMPV3_MODE_IS_INCLUDE;
 603			skb = add_grec(skb, pmc, type, 0, 0);
 604			spin_unlock_bh(&pmc->lock);
 605		}
 606		rcu_read_unlock();
 607	} else {
 608		spin_lock_bh(&pmc->lock);
 609		if (pmc->sfcount[MCAST_EXCLUDE])
 610			type = IGMPV3_MODE_IS_EXCLUDE;
 611		else
 612			type = IGMPV3_MODE_IS_INCLUDE;
 613		skb = add_grec(skb, pmc, type, 0, 0);
 614		spin_unlock_bh(&pmc->lock);
 615	}
 616	if (!skb)
 617		return 0;
 618	return igmpv3_sendpack(skb);
 619}
 620
 621/*
 622 * remove zero-count source records from a source filter list
 623 */
 624static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
 625{
 626	struct ip_sf_list *psf_prev, *psf_next, *psf;
 627
 628	psf_prev = NULL;
 629	for (psf = *ppsf; psf; psf = psf_next) {
 630		psf_next = psf->sf_next;
 631		if (psf->sf_crcount == 0) {
 632			if (psf_prev)
 633				psf_prev->sf_next = psf->sf_next;
 634			else
 635				*ppsf = psf->sf_next;
 636			kfree(psf);
 637		} else
 638			psf_prev = psf;
 639	}
 640}
 641
 642static void kfree_pmc(struct ip_mc_list *pmc)
 643{
 644	ip_sf_list_clear_all(pmc->sources);
 645	ip_sf_list_clear_all(pmc->tomb);
 646	kfree(pmc);
 647}
 648
 649static void igmpv3_send_cr(struct in_device *in_dev)
 650{
 651	struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
 652	struct sk_buff *skb = NULL;
 653	int type, dtype;
 654
 655	rcu_read_lock();
 656	spin_lock_bh(&in_dev->mc_tomb_lock);
 657
 658	/* deleted MCA's */
 659	pmc_prev = NULL;
 660	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) {
 661		pmc_next = pmc->next;
 662		if (pmc->sfmode == MCAST_INCLUDE) {
 663			type = IGMPV3_BLOCK_OLD_SOURCES;
 664			dtype = IGMPV3_BLOCK_OLD_SOURCES;
 665			skb = add_grec(skb, pmc, type, 1, 0);
 666			skb = add_grec(skb, pmc, dtype, 1, 1);
 667		}
 668		if (pmc->crcount) {
 669			if (pmc->sfmode == MCAST_EXCLUDE) {
 670				type = IGMPV3_CHANGE_TO_INCLUDE;
 671				skb = add_grec(skb, pmc, type, 1, 0);
 672			}
 673			pmc->crcount--;
 674			if (pmc->crcount == 0) {
 675				igmpv3_clear_zeros(&pmc->tomb);
 676				igmpv3_clear_zeros(&pmc->sources);
 677			}
 678		}
 679		if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
 680			if (pmc_prev)
 681				pmc_prev->next = pmc_next;
 682			else
 683				in_dev->mc_tomb = pmc_next;
 684			in_dev_put(pmc->interface);
 685			kfree_pmc(pmc);
 686		} else
 687			pmc_prev = pmc;
 688	}
 689	spin_unlock_bh(&in_dev->mc_tomb_lock);
 690
 691	/* change recs */
 692	for_each_pmc_rcu(in_dev, pmc) {
 693		spin_lock_bh(&pmc->lock);
 694		if (pmc->sfcount[MCAST_EXCLUDE]) {
 695			type = IGMPV3_BLOCK_OLD_SOURCES;
 696			dtype = IGMPV3_ALLOW_NEW_SOURCES;
 697		} else {
 698			type = IGMPV3_ALLOW_NEW_SOURCES;
 699			dtype = IGMPV3_BLOCK_OLD_SOURCES;
 700		}
 701		skb = add_grec(skb, pmc, type, 0, 0);
 702		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
 703
 704		/* filter mode changes */
 705		if (pmc->crcount) {
 706			if (pmc->sfmode == MCAST_EXCLUDE)
 707				type = IGMPV3_CHANGE_TO_EXCLUDE;
 708			else
 709				type = IGMPV3_CHANGE_TO_INCLUDE;
 710			skb = add_grec(skb, pmc, type, 0, 0);
 711			pmc->crcount--;
 712		}
 713		spin_unlock_bh(&pmc->lock);
 714	}
 715	rcu_read_unlock();
 716
 717	if (!skb)
 718		return;
 719	(void) igmpv3_sendpack(skb);
 720}
 721
 722static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
 723	int type)
 724{
 725	struct sk_buff *skb;
 726	struct iphdr *iph;
 727	struct igmphdr *ih;
 728	struct rtable *rt;
 729	struct net_device *dev = in_dev->dev;
 730	struct net *net = dev_net(dev);
 731	__be32	group = pmc ? pmc->multiaddr : 0;
 732	struct flowi4 fl4;
 733	__be32	dst;
 734	int hlen, tlen;
 735
 736	if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
 737		return igmpv3_send_report(in_dev, pmc);
 738
 739	if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
 740		return 0;
 741
 742	if (type == IGMP_HOST_LEAVE_MESSAGE)
 743		dst = IGMP_ALL_ROUTER;
 744	else
 745		dst = group;
 746
 747	rt = ip_route_output_ports(net, &fl4, NULL, dst, 0,
 748				   0, 0,
 749				   IPPROTO_IGMP, 0, dev->ifindex);
 750	if (IS_ERR(rt))
 751		return -1;
 752
 753	hlen = LL_RESERVED_SPACE(dev);
 754	tlen = dev->needed_tailroom;
 755	skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC);
 756	if (!skb) {
 757		ip_rt_put(rt);
 758		return -1;
 759	}
 760	skb->priority = TC_PRIO_CONTROL;
 761
 762	skb_dst_set(skb, &rt->dst);
 763
 764	skb_reserve(skb, hlen);
 765
 766	skb_reset_network_header(skb);
 767	iph = ip_hdr(skb);
 768	skb_put(skb, sizeof(struct iphdr) + 4);
 769
 770	iph->version  = 4;
 771	iph->ihl      = (sizeof(struct iphdr)+4)>>2;
 772	iph->tos      = 0xc0;
 773	iph->frag_off = htons(IP_DF);
 774	iph->ttl      = 1;
 775	iph->daddr    = dst;
 776	iph->saddr    = fl4.saddr;
 777	iph->protocol = IPPROTO_IGMP;
 778	ip_select_ident(net, skb, NULL);
 779	((u8 *)&iph[1])[0] = IPOPT_RA;
 780	((u8 *)&iph[1])[1] = 4;
 781	((u8 *)&iph[1])[2] = 0;
 782	((u8 *)&iph[1])[3] = 0;
 783
 784	ih = skb_put(skb, sizeof(struct igmphdr));
 785	ih->type = type;
 786	ih->code = 0;
 787	ih->csum = 0;
 788	ih->group = group;
 789	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 790
 791	return ip_local_out(net, skb->sk, skb);
 792}
 793
 794static void igmp_gq_timer_expire(struct timer_list *t)
 795{
 796	struct in_device *in_dev = from_timer(in_dev, t, mr_gq_timer);
 797
 798	in_dev->mr_gq_running = 0;
 799	igmpv3_send_report(in_dev, NULL);
 800	in_dev_put(in_dev);
 801}
 802
 803static void igmp_ifc_timer_expire(struct timer_list *t)
 804{
 805	struct in_device *in_dev = from_timer(in_dev, t, mr_ifc_timer);
 806	u32 mr_ifc_count;
 807
 808	igmpv3_send_cr(in_dev);
 809restart:
 810	mr_ifc_count = READ_ONCE(in_dev->mr_ifc_count);
 811
 812	if (mr_ifc_count) {
 813		if (cmpxchg(&in_dev->mr_ifc_count,
 814			    mr_ifc_count,
 815			    mr_ifc_count - 1) != mr_ifc_count)
 816			goto restart;
 817		igmp_ifc_start_timer(in_dev,
 818				     unsolicited_report_interval(in_dev));
 819	}
 820	in_dev_put(in_dev);
 821}
 822
 823static void igmp_ifc_event(struct in_device *in_dev)
 824{
 825	struct net *net = dev_net(in_dev->dev);
 826	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 827		return;
 828	WRITE_ONCE(in_dev->mr_ifc_count, in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv);
 829	igmp_ifc_start_timer(in_dev, 1);
 830}
 831
 832
 833static void igmp_timer_expire(struct timer_list *t)
 834{
 835	struct ip_mc_list *im = from_timer(im, t, timer);
 836	struct in_device *in_dev = im->interface;
 837
 838	spin_lock(&im->lock);
 839	im->tm_running = 0;
 840
 841	if (im->unsolicit_count && --im->unsolicit_count)
 
 842		igmp_start_timer(im, unsolicited_report_interval(in_dev));
 843
 844	im->reporter = 1;
 845	spin_unlock(&im->lock);
 846
 847	if (IGMP_V1_SEEN(in_dev))
 848		igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
 849	else if (IGMP_V2_SEEN(in_dev))
 850		igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
 851	else
 852		igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
 853
 854	ip_ma_put(im);
 855}
 856
 857/* mark EXCLUDE-mode sources */
 858static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 859{
 860	struct ip_sf_list *psf;
 861	int i, scount;
 862
 863	scount = 0;
 864	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 865		if (scount == nsrcs)
 866			break;
 867		for (i = 0; i < nsrcs; i++) {
 868			/* skip inactive filters */
 869			if (psf->sf_count[MCAST_INCLUDE] ||
 870			    pmc->sfcount[MCAST_EXCLUDE] !=
 871			    psf->sf_count[MCAST_EXCLUDE])
 872				break;
 873			if (srcs[i] == psf->sf_inaddr) {
 874				scount++;
 875				break;
 876			}
 877		}
 878	}
 879	pmc->gsquery = 0;
 880	if (scount == nsrcs)	/* all sources excluded */
 881		return 0;
 882	return 1;
 883}
 884
 885static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 886{
 887	struct ip_sf_list *psf;
 888	int i, scount;
 889
 890	if (pmc->sfmode == MCAST_EXCLUDE)
 891		return igmp_xmarksources(pmc, nsrcs, srcs);
 892
 893	/* mark INCLUDE-mode sources */
 894	scount = 0;
 895	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 896		if (scount == nsrcs)
 897			break;
 898		for (i = 0; i < nsrcs; i++)
 899			if (srcs[i] == psf->sf_inaddr) {
 900				psf->sf_gsresp = 1;
 901				scount++;
 902				break;
 903			}
 904	}
 905	if (!scount) {
 906		pmc->gsquery = 0;
 907		return 0;
 908	}
 909	pmc->gsquery = 1;
 910	return 1;
 911}
 912
 913/* return true if packet was dropped */
 914static bool igmp_heard_report(struct in_device *in_dev, __be32 group)
 915{
 916	struct ip_mc_list *im;
 917	struct net *net = dev_net(in_dev->dev);
 918
 919	/* Timers are only set for non-local groups */
 920
 921	if (group == IGMP_ALL_HOSTS)
 922		return false;
 923	if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
 924		return false;
 925
 926	rcu_read_lock();
 927	for_each_pmc_rcu(in_dev, im) {
 928		if (im->multiaddr == group) {
 929			igmp_stop_timer(im);
 930			break;
 931		}
 932	}
 933	rcu_read_unlock();
 934	return false;
 935}
 936
 937/* return true if packet was dropped */
 938static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
 939	int len)
 940{
 941	struct igmphdr 		*ih = igmp_hdr(skb);
 942	struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
 943	struct ip_mc_list	*im;
 944	__be32			group = ih->group;
 945	int			max_delay;
 946	int			mark = 0;
 947	struct net		*net = dev_net(in_dev->dev);
 948
 949
 950	if (len == 8) {
 951		if (ih->code == 0) {
 952			/* Alas, old v1 router presents here. */
 953
 954			max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 955			in_dev->mr_v1_seen = jiffies +
 956				(in_dev->mr_qrv * in_dev->mr_qi) +
 957				in_dev->mr_qri;
 958			group = 0;
 959		} else {
 960			/* v2 router present */
 961			max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
 962			in_dev->mr_v2_seen = jiffies +
 963				(in_dev->mr_qrv * in_dev->mr_qi) +
 964				in_dev->mr_qri;
 965		}
 966		/* cancel the interface change timer */
 967		WRITE_ONCE(in_dev->mr_ifc_count, 0);
 968		if (del_timer(&in_dev->mr_ifc_timer))
 969			__in_dev_put(in_dev);
 970		/* clear deleted report items */
 971		igmpv3_clear_delrec(in_dev);
 972	} else if (len < 12) {
 973		return true;	/* ignore bogus packet; freed by caller */
 974	} else if (IGMP_V1_SEEN(in_dev)) {
 975		/* This is a v3 query with v1 queriers present */
 976		max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 977		group = 0;
 978	} else if (IGMP_V2_SEEN(in_dev)) {
 979		/* this is a v3 query with v2 queriers present;
 980		 * Interpretation of the max_delay code is problematic here.
 981		 * A real v2 host would use ih_code directly, while v3 has a
 982		 * different encoding. We use the v3 encoding as more likely
 983		 * to be intended in a v3 query.
 984		 */
 985		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 986		if (!max_delay)
 987			max_delay = 1;	/* can't mod w/ 0 */
 988	} else { /* v3 */
 989		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
 990			return true;
 991
 992		ih3 = igmpv3_query_hdr(skb);
 993		if (ih3->nsrcs) {
 994			if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
 995					   + ntohs(ih3->nsrcs)*sizeof(__be32)))
 996				return true;
 997			ih3 = igmpv3_query_hdr(skb);
 998		}
 999
1000		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
1001		if (!max_delay)
1002			max_delay = 1;	/* can't mod w/ 0 */
1003		in_dev->mr_maxdelay = max_delay;
1004
1005		/* RFC3376, 4.1.6. QRV and 4.1.7. QQIC, when the most recently
1006		 * received value was zero, use the default or statically
1007		 * configured value.
1008		 */
1009		in_dev->mr_qrv = ih3->qrv ?: net->ipv4.sysctl_igmp_qrv;
1010		in_dev->mr_qi = IGMPV3_QQIC(ih3->qqic)*HZ ?: IGMP_QUERY_INTERVAL;
1011
1012		/* RFC3376, 8.3. Query Response Interval:
1013		 * The number of seconds represented by the [Query Response
1014		 * Interval] must be less than the [Query Interval].
1015		 */
1016		if (in_dev->mr_qri >= in_dev->mr_qi)
1017			in_dev->mr_qri = (in_dev->mr_qi/HZ - 1)*HZ;
1018
1019		if (!group) { /* general query */
1020			if (ih3->nsrcs)
1021				return true;	/* no sources allowed */
1022			igmp_gq_start_timer(in_dev);
1023			return false;
1024		}
1025		/* mark sources to include, if group & source-specific */
1026		mark = ih3->nsrcs != 0;
1027	}
1028
1029	/*
1030	 * - Start the timers in all of our membership records
1031	 *   that the query applies to for the interface on
1032	 *   which the query arrived excl. those that belong
1033	 *   to a "local" group (224.0.0.X)
1034	 * - For timers already running check if they need to
1035	 *   be reset.
1036	 * - Use the igmp->igmp_code field as the maximum
1037	 *   delay possible
1038	 */
1039	rcu_read_lock();
1040	for_each_pmc_rcu(in_dev, im) {
1041		int changed;
1042
1043		if (group && group != im->multiaddr)
1044			continue;
1045		if (im->multiaddr == IGMP_ALL_HOSTS)
1046			continue;
1047		if (ipv4_is_local_multicast(im->multiaddr) &&
1048		    !net->ipv4.sysctl_igmp_llm_reports)
1049			continue;
1050		spin_lock_bh(&im->lock);
1051		if (im->tm_running)
1052			im->gsquery = im->gsquery && mark;
1053		else
1054			im->gsquery = mark;
1055		changed = !im->gsquery ||
1056			igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
1057		spin_unlock_bh(&im->lock);
1058		if (changed)
1059			igmp_mod_timer(im, max_delay);
1060	}
1061	rcu_read_unlock();
1062	return false;
1063}
1064
1065/* called in rcu_read_lock() section */
1066int igmp_rcv(struct sk_buff *skb)
1067{
1068	/* This basically follows the spec line by line -- see RFC1112 */
1069	struct igmphdr *ih;
1070	struct net_device *dev = skb->dev;
1071	struct in_device *in_dev;
1072	int len = skb->len;
1073	bool dropped = true;
1074
1075	if (netif_is_l3_master(dev)) {
1076		dev = dev_get_by_index_rcu(dev_net(dev), IPCB(skb)->iif);
1077		if (!dev)
1078			goto drop;
1079	}
1080
1081	in_dev = __in_dev_get_rcu(dev);
1082	if (!in_dev)
1083		goto drop;
1084
1085	if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
1086		goto drop;
1087
1088	if (skb_checksum_simple_validate(skb))
1089		goto drop;
1090
1091	ih = igmp_hdr(skb);
1092	switch (ih->type) {
1093	case IGMP_HOST_MEMBERSHIP_QUERY:
1094		dropped = igmp_heard_query(in_dev, skb, len);
1095		break;
1096	case IGMP_HOST_MEMBERSHIP_REPORT:
1097	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1098		/* Is it our report looped back? */
1099		if (rt_is_output_route(skb_rtable(skb)))
1100			break;
1101		/* don't rely on MC router hearing unicast reports */
1102		if (skb->pkt_type == PACKET_MULTICAST ||
1103		    skb->pkt_type == PACKET_BROADCAST)
1104			dropped = igmp_heard_report(in_dev, ih->group);
1105		break;
1106	case IGMP_PIM:
1107#ifdef CONFIG_IP_PIMSM_V1
1108		return pim_rcv_v1(skb);
1109#endif
1110	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1111	case IGMP_DVMRP:
1112	case IGMP_TRACE:
1113	case IGMP_HOST_LEAVE_MESSAGE:
1114	case IGMP_MTRACE:
1115	case IGMP_MTRACE_RESP:
1116		break;
1117	default:
1118		break;
1119	}
1120
1121drop:
1122	if (dropped)
1123		kfree_skb(skb);
1124	else
1125		consume_skb(skb);
1126	return 0;
1127}
1128
1129#endif
1130
1131
1132/*
1133 *	Add a filter to a device
1134 */
1135
1136static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1137{
1138	char buf[MAX_ADDR_LEN];
1139	struct net_device *dev = in_dev->dev;
1140
1141	/* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1142	   We will get multicast token leakage, when IFF_MULTICAST
1143	   is changed. This check should be done in ndo_set_rx_mode
1144	   routine. Something sort of:
1145	   if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1146	   --ANK
1147	   */
1148	if (arp_mc_map(addr, buf, dev, 0) == 0)
1149		dev_mc_add(dev, buf);
1150}
1151
1152/*
1153 *	Remove a filter from a device
1154 */
1155
1156static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1157{
1158	char buf[MAX_ADDR_LEN];
1159	struct net_device *dev = in_dev->dev;
1160
1161	if (arp_mc_map(addr, buf, dev, 0) == 0)
1162		dev_mc_del(dev, buf);
1163}
1164
1165#ifdef CONFIG_IP_MULTICAST
1166/*
1167 * deleted ip_mc_list manipulation
1168 */
1169static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im,
1170			      gfp_t gfp)
1171{
1172	struct ip_mc_list *pmc;
1173	struct net *net = dev_net(in_dev->dev);
1174
1175	/* this is an "ip_mc_list" for convenience; only the fields below
1176	 * are actually used. In particular, the refcnt and users are not
1177	 * used for management of the delete list. Using the same structure
1178	 * for deleted items allows change reports to use common code with
1179	 * non-deleted or query-response MCA's.
1180	 */
1181	pmc = kzalloc(sizeof(*pmc), gfp);
1182	if (!pmc)
1183		return;
1184	spin_lock_init(&pmc->lock);
1185	spin_lock_bh(&im->lock);
1186	pmc->interface = im->interface;
1187	in_dev_hold(in_dev);
1188	pmc->multiaddr = im->multiaddr;
1189	pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1190	pmc->sfmode = im->sfmode;
1191	if (pmc->sfmode == MCAST_INCLUDE) {
1192		struct ip_sf_list *psf;
1193
1194		pmc->tomb = im->tomb;
1195		pmc->sources = im->sources;
1196		im->tomb = im->sources = NULL;
1197		for (psf = pmc->sources; psf; psf = psf->sf_next)
1198			psf->sf_crcount = pmc->crcount;
1199	}
1200	spin_unlock_bh(&im->lock);
1201
1202	spin_lock_bh(&in_dev->mc_tomb_lock);
1203	pmc->next = in_dev->mc_tomb;
1204	in_dev->mc_tomb = pmc;
1205	spin_unlock_bh(&in_dev->mc_tomb_lock);
1206}
1207
1208/*
1209 * restore ip_mc_list deleted records
1210 */
1211static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1212{
1213	struct ip_mc_list *pmc, *pmc_prev;
1214	struct ip_sf_list *psf;
1215	struct net *net = dev_net(in_dev->dev);
1216	__be32 multiaddr = im->multiaddr;
1217
1218	spin_lock_bh(&in_dev->mc_tomb_lock);
1219	pmc_prev = NULL;
1220	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) {
1221		if (pmc->multiaddr == multiaddr)
1222			break;
1223		pmc_prev = pmc;
1224	}
1225	if (pmc) {
1226		if (pmc_prev)
1227			pmc_prev->next = pmc->next;
1228		else
1229			in_dev->mc_tomb = pmc->next;
1230	}
1231	spin_unlock_bh(&in_dev->mc_tomb_lock);
1232
1233	spin_lock_bh(&im->lock);
1234	if (pmc) {
1235		im->interface = pmc->interface;
1236		if (im->sfmode == MCAST_INCLUDE) {
1237			swap(im->tomb, pmc->tomb);
1238			swap(im->sources, pmc->sources);
 
 
1239			for (psf = im->sources; psf; psf = psf->sf_next)
1240				psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1241		} else {
1242			im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1243		}
1244		in_dev_put(pmc->interface);
1245		kfree_pmc(pmc);
1246	}
1247	spin_unlock_bh(&im->lock);
1248}
1249
1250/*
1251 * flush ip_mc_list deleted records
1252 */
1253static void igmpv3_clear_delrec(struct in_device *in_dev)
1254{
1255	struct ip_mc_list *pmc, *nextpmc;
1256
1257	spin_lock_bh(&in_dev->mc_tomb_lock);
1258	pmc = in_dev->mc_tomb;
1259	in_dev->mc_tomb = NULL;
1260	spin_unlock_bh(&in_dev->mc_tomb_lock);
1261
1262	for (; pmc; pmc = nextpmc) {
1263		nextpmc = pmc->next;
1264		ip_mc_clear_src(pmc);
1265		in_dev_put(pmc->interface);
1266		kfree_pmc(pmc);
1267	}
1268	/* clear dead sources, too */
1269	rcu_read_lock();
1270	for_each_pmc_rcu(in_dev, pmc) {
1271		struct ip_sf_list *psf;
1272
1273		spin_lock_bh(&pmc->lock);
1274		psf = pmc->tomb;
1275		pmc->tomb = NULL;
1276		spin_unlock_bh(&pmc->lock);
1277		ip_sf_list_clear_all(psf);
 
 
 
1278	}
1279	rcu_read_unlock();
1280}
1281#endif
1282
1283static void __igmp_group_dropped(struct ip_mc_list *im, gfp_t gfp)
1284{
1285	struct in_device *in_dev = im->interface;
1286#ifdef CONFIG_IP_MULTICAST
1287	struct net *net = dev_net(in_dev->dev);
1288	int reporter;
1289#endif
1290
1291	if (im->loaded) {
1292		im->loaded = 0;
1293		ip_mc_filter_del(in_dev, im->multiaddr);
1294	}
1295
1296#ifdef CONFIG_IP_MULTICAST
1297	if (im->multiaddr == IGMP_ALL_HOSTS)
1298		return;
1299	if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1300		return;
1301
1302	reporter = im->reporter;
1303	igmp_stop_timer(im);
1304
1305	if (!in_dev->dead) {
1306		if (IGMP_V1_SEEN(in_dev))
1307			return;
1308		if (IGMP_V2_SEEN(in_dev)) {
1309			if (reporter)
1310				igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1311			return;
1312		}
1313		/* IGMPv3 */
1314		igmpv3_add_delrec(in_dev, im, gfp);
1315
1316		igmp_ifc_event(in_dev);
1317	}
1318#endif
1319}
1320
1321static void igmp_group_dropped(struct ip_mc_list *im)
1322{
1323	__igmp_group_dropped(im, GFP_KERNEL);
1324}
1325
1326static void igmp_group_added(struct ip_mc_list *im)
1327{
1328	struct in_device *in_dev = im->interface;
1329#ifdef CONFIG_IP_MULTICAST
1330	struct net *net = dev_net(in_dev->dev);
1331#endif
1332
1333	if (im->loaded == 0) {
1334		im->loaded = 1;
1335		ip_mc_filter_add(in_dev, im->multiaddr);
1336	}
1337
1338#ifdef CONFIG_IP_MULTICAST
1339	if (im->multiaddr == IGMP_ALL_HOSTS)
1340		return;
1341	if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1342		return;
1343
1344	if (in_dev->dead)
1345		return;
1346
1347	im->unsolicit_count = net->ipv4.sysctl_igmp_qrv;
1348	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1349		spin_lock_bh(&im->lock);
1350		igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY);
1351		spin_unlock_bh(&im->lock);
1352		return;
1353	}
1354	/* else, v3 */
1355
1356	/* Based on RFC3376 5.1, for newly added INCLUDE SSM, we should
1357	 * not send filter-mode change record as the mode should be from
1358	 * IN() to IN(A).
1359	 */
1360	if (im->sfmode == MCAST_EXCLUDE)
1361		im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1362
1363	igmp_ifc_event(in_dev);
1364#endif
1365}
1366
1367
1368/*
1369 *	Multicast list managers
1370 */
1371
1372static u32 ip_mc_hash(const struct ip_mc_list *im)
1373{
1374	return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
1375}
1376
1377static void ip_mc_hash_add(struct in_device *in_dev,
1378			   struct ip_mc_list *im)
1379{
1380	struct ip_mc_list __rcu **mc_hash;
1381	u32 hash;
1382
1383	mc_hash = rtnl_dereference(in_dev->mc_hash);
1384	if (mc_hash) {
1385		hash = ip_mc_hash(im);
1386		im->next_hash = mc_hash[hash];
1387		rcu_assign_pointer(mc_hash[hash], im);
1388		return;
1389	}
1390
1391	/* do not use a hash table for small number of items */
1392	if (in_dev->mc_count < 4)
1393		return;
1394
1395	mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
1396			  GFP_KERNEL);
1397	if (!mc_hash)
1398		return;
1399
1400	for_each_pmc_rtnl(in_dev, im) {
1401		hash = ip_mc_hash(im);
1402		im->next_hash = mc_hash[hash];
1403		RCU_INIT_POINTER(mc_hash[hash], im);
1404	}
1405
1406	rcu_assign_pointer(in_dev->mc_hash, mc_hash);
1407}
1408
1409static void ip_mc_hash_remove(struct in_device *in_dev,
1410			      struct ip_mc_list *im)
1411{
1412	struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
1413	struct ip_mc_list *aux;
1414
1415	if (!mc_hash)
1416		return;
1417	mc_hash += ip_mc_hash(im);
1418	while ((aux = rtnl_dereference(*mc_hash)) != im)
1419		mc_hash = &aux->next_hash;
1420	*mc_hash = im->next_hash;
1421}
1422
1423
1424/*
1425 *	A socket has joined a multicast group on device dev.
1426 */
1427static void ____ip_mc_inc_group(struct in_device *in_dev, __be32 addr,
1428				unsigned int mode, gfp_t gfp)
1429{
1430	struct ip_mc_list *im;
 
 
 
1431
1432	ASSERT_RTNL();
1433
1434	for_each_pmc_rtnl(in_dev, im) {
1435		if (im->multiaddr == addr) {
1436			im->users++;
1437			ip_mc_add_src(in_dev, &addr, mode, 0, NULL, 0);
1438			goto out;
1439		}
1440	}
1441
1442	im = kzalloc(sizeof(*im), gfp);
1443	if (!im)
1444		goto out;
1445
1446	im->users = 1;
1447	im->interface = in_dev;
1448	in_dev_hold(in_dev);
1449	im->multiaddr = addr;
1450	/* initial mode is (EX, empty) */
1451	im->sfmode = mode;
1452	im->sfcount[mode] = 1;
1453	refcount_set(&im->refcnt, 1);
1454	spin_lock_init(&im->lock);
1455#ifdef CONFIG_IP_MULTICAST
1456	timer_setup(&im->timer, igmp_timer_expire, 0);
 
1457#endif
1458
1459	im->next_rcu = in_dev->mc_list;
1460	in_dev->mc_count++;
1461	rcu_assign_pointer(in_dev->mc_list, im);
1462
1463	ip_mc_hash_add(in_dev, im);
1464
1465#ifdef CONFIG_IP_MULTICAST
1466	igmpv3_del_delrec(in_dev, im);
1467#endif
1468	igmp_group_added(im);
1469	if (!in_dev->dead)
1470		ip_rt_multicast_event(in_dev);
1471out:
1472	return;
1473}
1474
1475void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr, gfp_t gfp)
1476{
1477	____ip_mc_inc_group(in_dev, addr, MCAST_EXCLUDE, gfp);
1478}
1479EXPORT_SYMBOL(__ip_mc_inc_group);
1480
1481void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1482{
1483	__ip_mc_inc_group(in_dev, addr, GFP_KERNEL);
1484}
1485EXPORT_SYMBOL(ip_mc_inc_group);
1486
1487static int ip_mc_check_iphdr(struct sk_buff *skb)
1488{
1489	const struct iphdr *iph;
1490	unsigned int len;
1491	unsigned int offset = skb_network_offset(skb) + sizeof(*iph);
1492
1493	if (!pskb_may_pull(skb, offset))
1494		return -EINVAL;
1495
1496	iph = ip_hdr(skb);
1497
1498	if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph))
1499		return -EINVAL;
1500
1501	offset += ip_hdrlen(skb) - sizeof(*iph);
1502
1503	if (!pskb_may_pull(skb, offset))
1504		return -EINVAL;
1505
1506	iph = ip_hdr(skb);
1507
1508	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1509		return -EINVAL;
1510
1511	len = skb_network_offset(skb) + ntohs(iph->tot_len);
1512	if (skb->len < len || len < offset)
1513		return -EINVAL;
1514
1515	skb_set_transport_header(skb, offset);
1516
1517	return 0;
1518}
1519
1520static int ip_mc_check_igmp_reportv3(struct sk_buff *skb)
1521{
1522	unsigned int len = skb_transport_offset(skb);
1523
1524	len += sizeof(struct igmpv3_report);
1525
1526	return ip_mc_may_pull(skb, len) ? 0 : -EINVAL;
1527}
1528
1529static int ip_mc_check_igmp_query(struct sk_buff *skb)
1530{
1531	unsigned int transport_len = ip_transport_len(skb);
1532	unsigned int len;
 
 
 
1533
1534	/* IGMPv{1,2}? */
1535	if (transport_len != sizeof(struct igmphdr)) {
1536		/* or IGMPv3? */
1537		if (transport_len < sizeof(struct igmpv3_query))
1538			return -EINVAL;
1539
1540		len = skb_transport_offset(skb) + sizeof(struct igmpv3_query);
1541		if (!ip_mc_may_pull(skb, len))
1542			return -EINVAL;
1543	}
1544
1545	/* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1546	 * all-systems destination addresses (224.0.0.1) for general queries
1547	 */
1548	if (!igmp_hdr(skb)->group &&
1549	    ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP))
1550		return -EINVAL;
1551
1552	return 0;
1553}
1554
1555static int ip_mc_check_igmp_msg(struct sk_buff *skb)
1556{
1557	switch (igmp_hdr(skb)->type) {
1558	case IGMP_HOST_LEAVE_MESSAGE:
1559	case IGMP_HOST_MEMBERSHIP_REPORT:
1560	case IGMPV2_HOST_MEMBERSHIP_REPORT:
 
1561		return 0;
1562	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1563		return ip_mc_check_igmp_reportv3(skb);
1564	case IGMP_HOST_MEMBERSHIP_QUERY:
1565		return ip_mc_check_igmp_query(skb);
1566	default:
1567		return -ENOMSG;
1568	}
1569}
1570
1571static __sum16 ip_mc_validate_checksum(struct sk_buff *skb)
1572{
1573	return skb_checksum_simple_validate(skb);
1574}
1575
1576static int ip_mc_check_igmp_csum(struct sk_buff *skb)
 
1577{
1578	unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr);
1579	unsigned int transport_len = ip_transport_len(skb);
1580	struct sk_buff *skb_chk;
 
 
 
1581
1582	if (!ip_mc_may_pull(skb, len))
1583		return -EINVAL;
1584
1585	skb_chk = skb_checksum_trimmed(skb, transport_len,
1586				       ip_mc_validate_checksum);
1587	if (!skb_chk)
1588		return -EINVAL;
1589
1590	if (skb_chk != skb)
 
 
 
 
 
 
 
 
 
 
1591		kfree_skb(skb_chk);
1592
1593	return 0;
 
 
 
 
 
 
1594}
1595
1596/**
1597 * ip_mc_check_igmp - checks whether this is a sane IGMP packet
1598 * @skb: the skb to validate
 
1599 *
1600 * Checks whether an IPv4 packet is a valid IGMP packet. If so sets
1601 * skb transport header accordingly and returns zero.
1602 *
1603 * -EINVAL: A broken packet was detected, i.e. it violates some internet
1604 *  standard
1605 * -ENOMSG: IP header validation succeeded but it is not an IGMP packet.
1606 * -ENOMEM: A memory allocation failure happened.
1607 *
 
 
 
 
 
 
 
 
1608 * Caller needs to set the skb network header and free any returned skb if it
1609 * differs from the provided skb.
1610 */
1611int ip_mc_check_igmp(struct sk_buff *skb)
1612{
1613	int ret = ip_mc_check_iphdr(skb);
1614
1615	if (ret < 0)
1616		return ret;
1617
1618	if (ip_hdr(skb)->protocol != IPPROTO_IGMP)
1619		return -ENOMSG;
1620
1621	ret = ip_mc_check_igmp_csum(skb);
1622	if (ret < 0)
1623		return ret;
1624
1625	return ip_mc_check_igmp_msg(skb);
1626}
1627EXPORT_SYMBOL(ip_mc_check_igmp);
1628
1629/*
1630 *	Resend IGMP JOIN report; used by netdev notifier.
1631 */
1632static void ip_mc_rejoin_groups(struct in_device *in_dev)
1633{
1634#ifdef CONFIG_IP_MULTICAST
1635	struct ip_mc_list *im;
1636	int type;
1637	struct net *net = dev_net(in_dev->dev);
1638
1639	ASSERT_RTNL();
1640
1641	for_each_pmc_rtnl(in_dev, im) {
1642		if (im->multiaddr == IGMP_ALL_HOSTS)
1643			continue;
1644		if (ipv4_is_local_multicast(im->multiaddr) &&
1645		    !net->ipv4.sysctl_igmp_llm_reports)
1646			continue;
1647
1648		/* a failover is happening and switches
1649		 * must be notified immediately
1650		 */
1651		if (IGMP_V1_SEEN(in_dev))
1652			type = IGMP_HOST_MEMBERSHIP_REPORT;
1653		else if (IGMP_V2_SEEN(in_dev))
1654			type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1655		else
1656			type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1657		igmp_send_report(in_dev, im, type);
1658	}
1659#endif
1660}
1661
1662/*
1663 *	A socket has left a multicast group on device dev
1664 */
1665
1666void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp)
1667{
1668	struct ip_mc_list *i;
1669	struct ip_mc_list __rcu **ip;
1670
1671	ASSERT_RTNL();
1672
1673	for (ip = &in_dev->mc_list;
1674	     (i = rtnl_dereference(*ip)) != NULL;
1675	     ip = &i->next_rcu) {
1676		if (i->multiaddr == addr) {
1677			if (--i->users == 0) {
1678				ip_mc_hash_remove(in_dev, i);
1679				*ip = i->next_rcu;
1680				in_dev->mc_count--;
1681				__igmp_group_dropped(i, gfp);
1682				ip_mc_clear_src(i);
1683
1684				if (!in_dev->dead)
1685					ip_rt_multicast_event(in_dev);
1686
1687				ip_ma_put(i);
1688				return;
1689			}
1690			break;
1691		}
1692	}
1693}
1694EXPORT_SYMBOL(__ip_mc_dec_group);
1695
1696/* Device changing type */
1697
1698void ip_mc_unmap(struct in_device *in_dev)
1699{
1700	struct ip_mc_list *pmc;
1701
1702	ASSERT_RTNL();
1703
1704	for_each_pmc_rtnl(in_dev, pmc)
1705		igmp_group_dropped(pmc);
1706}
1707
1708void ip_mc_remap(struct in_device *in_dev)
1709{
1710	struct ip_mc_list *pmc;
1711
1712	ASSERT_RTNL();
1713
1714	for_each_pmc_rtnl(in_dev, pmc) {
1715#ifdef CONFIG_IP_MULTICAST
1716		igmpv3_del_delrec(in_dev, pmc);
1717#endif
1718		igmp_group_added(pmc);
1719	}
1720}
1721
1722/* Device going down */
1723
1724void ip_mc_down(struct in_device *in_dev)
1725{
1726	struct ip_mc_list *pmc;
1727
1728	ASSERT_RTNL();
1729
1730	for_each_pmc_rtnl(in_dev, pmc)
1731		igmp_group_dropped(pmc);
1732
1733#ifdef CONFIG_IP_MULTICAST
1734	WRITE_ONCE(in_dev->mr_ifc_count, 0);
1735	if (del_timer(&in_dev->mr_ifc_timer))
1736		__in_dev_put(in_dev);
1737	in_dev->mr_gq_running = 0;
1738	if (del_timer(&in_dev->mr_gq_timer))
1739		__in_dev_put(in_dev);
1740#endif
1741
1742	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1743}
1744
1745#ifdef CONFIG_IP_MULTICAST
1746static void ip_mc_reset(struct in_device *in_dev)
1747{
 
1748	struct net *net = dev_net(in_dev->dev);
1749
1750	in_dev->mr_qi = IGMP_QUERY_INTERVAL;
1751	in_dev->mr_qri = IGMP_QUERY_RESPONSE_INTERVAL;
1752	in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1753}
1754#else
1755static void ip_mc_reset(struct in_device *in_dev)
1756{
1757}
1758#endif
1759
1760void ip_mc_init_dev(struct in_device *in_dev)
1761{
1762	ASSERT_RTNL();
1763
1764#ifdef CONFIG_IP_MULTICAST
1765	timer_setup(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 0);
1766	timer_setup(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 0);
 
1767#endif
1768	ip_mc_reset(in_dev);
1769
1770	spin_lock_init(&in_dev->mc_tomb_lock);
1771}
1772
1773/* Device going up */
1774
1775void ip_mc_up(struct in_device *in_dev)
1776{
1777	struct ip_mc_list *pmc;
 
 
 
1778
1779	ASSERT_RTNL();
1780
1781	ip_mc_reset(in_dev);
 
 
1782	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1783
1784	for_each_pmc_rtnl(in_dev, pmc) {
1785#ifdef CONFIG_IP_MULTICAST
1786		igmpv3_del_delrec(in_dev, pmc);
1787#endif
1788		igmp_group_added(pmc);
1789	}
1790}
1791
1792/*
1793 *	Device is about to be destroyed: clean up.
1794 */
1795
1796void ip_mc_destroy_dev(struct in_device *in_dev)
1797{
1798	struct ip_mc_list *i;
1799
1800	ASSERT_RTNL();
1801
1802	/* Deactivate timers */
1803	ip_mc_down(in_dev);
1804#ifdef CONFIG_IP_MULTICAST
1805	igmpv3_clear_delrec(in_dev);
1806#endif
1807
1808	while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1809		in_dev->mc_list = i->next_rcu;
1810		in_dev->mc_count--;
1811		ip_mc_clear_src(i);
1812		ip_ma_put(i);
1813	}
1814}
1815
1816/* RTNL is locked */
1817static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1818{
1819	struct net_device *dev = NULL;
1820	struct in_device *idev = NULL;
1821
1822	if (imr->imr_ifindex) {
1823		idev = inetdev_by_index(net, imr->imr_ifindex);
1824		return idev;
1825	}
1826	if (imr->imr_address.s_addr) {
1827		dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1828		if (!dev)
1829			return NULL;
1830	}
1831
1832	if (!dev) {
1833		struct rtable *rt = ip_route_output(net,
1834						    imr->imr_multiaddr.s_addr,
1835						    0, 0, 0);
1836		if (!IS_ERR(rt)) {
1837			dev = rt->dst.dev;
1838			ip_rt_put(rt);
1839		}
1840	}
1841	if (dev) {
1842		imr->imr_ifindex = dev->ifindex;
1843		idev = __in_dev_get_rtnl(dev);
1844	}
1845	return idev;
1846}
1847
1848/*
1849 *	Join a socket to a group
1850 */
1851
1852static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1853	__be32 *psfsrc)
1854{
1855	struct ip_sf_list *psf, *psf_prev;
1856	int rv = 0;
1857
1858	psf_prev = NULL;
1859	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1860		if (psf->sf_inaddr == *psfsrc)
1861			break;
1862		psf_prev = psf;
1863	}
1864	if (!psf || psf->sf_count[sfmode] == 0) {
1865		/* source filter not found, or count wrong =>  bug */
1866		return -ESRCH;
1867	}
1868	psf->sf_count[sfmode]--;
1869	if (psf->sf_count[sfmode] == 0) {
1870		ip_rt_multicast_event(pmc->interface);
1871	}
1872	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1873#ifdef CONFIG_IP_MULTICAST
1874		struct in_device *in_dev = pmc->interface;
1875		struct net *net = dev_net(in_dev->dev);
1876#endif
1877
1878		/* no more filters for this source */
1879		if (psf_prev)
1880			psf_prev->sf_next = psf->sf_next;
1881		else
1882			pmc->sources = psf->sf_next;
1883#ifdef CONFIG_IP_MULTICAST
1884		if (psf->sf_oldin &&
1885		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1886			psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1887			psf->sf_next = pmc->tomb;
1888			pmc->tomb = psf;
1889			rv = 1;
1890		} else
1891#endif
1892			kfree(psf);
1893	}
1894	return rv;
1895}
1896
1897#ifndef CONFIG_IP_MULTICAST
1898#define igmp_ifc_event(x)	do { } while (0)
1899#endif
1900
1901static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1902			 int sfcount, __be32 *psfsrc, int delta)
1903{
1904	struct ip_mc_list *pmc;
1905	int	changerec = 0;
1906	int	i, err;
1907
1908	if (!in_dev)
1909		return -ENODEV;
1910	rcu_read_lock();
1911	for_each_pmc_rcu(in_dev, pmc) {
1912		if (*pmca == pmc->multiaddr)
1913			break;
1914	}
1915	if (!pmc) {
1916		/* MCA not found?? bug */
1917		rcu_read_unlock();
1918		return -ESRCH;
1919	}
1920	spin_lock_bh(&pmc->lock);
1921	rcu_read_unlock();
1922#ifdef CONFIG_IP_MULTICAST
1923	sf_markstate(pmc);
1924#endif
1925	if (!delta) {
1926		err = -EINVAL;
1927		if (!pmc->sfcount[sfmode])
1928			goto out_unlock;
1929		pmc->sfcount[sfmode]--;
1930	}
1931	err = 0;
1932	for (i = 0; i < sfcount; i++) {
1933		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1934
1935		changerec |= rv > 0;
1936		if (!err && rv < 0)
1937			err = rv;
1938	}
1939	if (pmc->sfmode == MCAST_EXCLUDE &&
1940	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1941	    pmc->sfcount[MCAST_INCLUDE]) {
1942#ifdef CONFIG_IP_MULTICAST
1943		struct ip_sf_list *psf;
1944		struct net *net = dev_net(in_dev->dev);
1945#endif
1946
1947		/* filter mode change */
1948		pmc->sfmode = MCAST_INCLUDE;
1949#ifdef CONFIG_IP_MULTICAST
1950		pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1951		WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount);
1952		for (psf = pmc->sources; psf; psf = psf->sf_next)
1953			psf->sf_crcount = 0;
1954		igmp_ifc_event(pmc->interface);
1955	} else if (sf_setstate(pmc) || changerec) {
1956		igmp_ifc_event(pmc->interface);
1957#endif
1958	}
1959out_unlock:
1960	spin_unlock_bh(&pmc->lock);
1961	return err;
1962}
1963
1964/*
1965 * Add multicast single-source filter to the interface list
1966 */
1967static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1968	__be32 *psfsrc)
1969{
1970	struct ip_sf_list *psf, *psf_prev;
1971
1972	psf_prev = NULL;
1973	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1974		if (psf->sf_inaddr == *psfsrc)
1975			break;
1976		psf_prev = psf;
1977	}
1978	if (!psf) {
1979		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1980		if (!psf)
1981			return -ENOBUFS;
1982		psf->sf_inaddr = *psfsrc;
1983		if (psf_prev) {
1984			psf_prev->sf_next = psf;
1985		} else
1986			pmc->sources = psf;
1987	}
1988	psf->sf_count[sfmode]++;
1989	if (psf->sf_count[sfmode] == 1) {
1990		ip_rt_multicast_event(pmc->interface);
1991	}
1992	return 0;
1993}
1994
1995#ifdef CONFIG_IP_MULTICAST
1996static void sf_markstate(struct ip_mc_list *pmc)
1997{
1998	struct ip_sf_list *psf;
1999	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
2000
2001	for (psf = pmc->sources; psf; psf = psf->sf_next)
2002		if (pmc->sfcount[MCAST_EXCLUDE]) {
2003			psf->sf_oldin = mca_xcount ==
2004				psf->sf_count[MCAST_EXCLUDE] &&
2005				!psf->sf_count[MCAST_INCLUDE];
2006		} else
2007			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2008}
2009
2010static int sf_setstate(struct ip_mc_list *pmc)
2011{
2012	struct ip_sf_list *psf, *dpsf;
2013	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
2014	int qrv = pmc->interface->mr_qrv;
2015	int new_in, rv;
2016
2017	rv = 0;
2018	for (psf = pmc->sources; psf; psf = psf->sf_next) {
2019		if (pmc->sfcount[MCAST_EXCLUDE]) {
2020			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2021				!psf->sf_count[MCAST_INCLUDE];
2022		} else
2023			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2024		if (new_in) {
2025			if (!psf->sf_oldin) {
2026				struct ip_sf_list *prev = NULL;
2027
2028				for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) {
2029					if (dpsf->sf_inaddr == psf->sf_inaddr)
2030						break;
2031					prev = dpsf;
2032				}
2033				if (dpsf) {
2034					if (prev)
2035						prev->sf_next = dpsf->sf_next;
2036					else
2037						pmc->tomb = dpsf->sf_next;
2038					kfree(dpsf);
2039				}
2040				psf->sf_crcount = qrv;
2041				rv++;
2042			}
2043		} else if (psf->sf_oldin) {
2044
2045			psf->sf_crcount = 0;
2046			/*
2047			 * add or update "delete" records if an active filter
2048			 * is now inactive
2049			 */
2050			for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next)
2051				if (dpsf->sf_inaddr == psf->sf_inaddr)
2052					break;
2053			if (!dpsf) {
2054				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
2055				if (!dpsf)
2056					continue;
2057				*dpsf = *psf;
2058				/* pmc->lock held by callers */
2059				dpsf->sf_next = pmc->tomb;
2060				pmc->tomb = dpsf;
2061			}
2062			dpsf->sf_crcount = qrv;
2063			rv++;
2064		}
2065	}
2066	return rv;
2067}
2068#endif
2069
2070/*
2071 * Add multicast source filter list to the interface list
2072 */
2073static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
2074			 int sfcount, __be32 *psfsrc, int delta)
2075{
2076	struct ip_mc_list *pmc;
2077	int	isexclude;
2078	int	i, err;
2079
2080	if (!in_dev)
2081		return -ENODEV;
2082	rcu_read_lock();
2083	for_each_pmc_rcu(in_dev, pmc) {
2084		if (*pmca == pmc->multiaddr)
2085			break;
2086	}
2087	if (!pmc) {
2088		/* MCA not found?? bug */
2089		rcu_read_unlock();
2090		return -ESRCH;
2091	}
2092	spin_lock_bh(&pmc->lock);
2093	rcu_read_unlock();
2094
2095#ifdef CONFIG_IP_MULTICAST
2096	sf_markstate(pmc);
2097#endif
2098	isexclude = pmc->sfmode == MCAST_EXCLUDE;
2099	if (!delta)
2100		pmc->sfcount[sfmode]++;
2101	err = 0;
2102	for (i = 0; i < sfcount; i++) {
2103		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2104		if (err)
2105			break;
2106	}
2107	if (err) {
2108		int j;
2109
2110		if (!delta)
2111			pmc->sfcount[sfmode]--;
2112		for (j = 0; j < i; j++)
2113			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2114	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
2115#ifdef CONFIG_IP_MULTICAST
2116		struct ip_sf_list *psf;
2117		struct net *net = dev_net(pmc->interface->dev);
2118		in_dev = pmc->interface;
2119#endif
2120
2121		/* filter mode change */
2122		if (pmc->sfcount[MCAST_EXCLUDE])
2123			pmc->sfmode = MCAST_EXCLUDE;
2124		else if (pmc->sfcount[MCAST_INCLUDE])
2125			pmc->sfmode = MCAST_INCLUDE;
2126#ifdef CONFIG_IP_MULTICAST
2127		/* else no filters; keep old mode for reports */
2128
2129		pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
2130		WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount);
2131		for (psf = pmc->sources; psf; psf = psf->sf_next)
2132			psf->sf_crcount = 0;
2133		igmp_ifc_event(in_dev);
2134	} else if (sf_setstate(pmc)) {
2135		igmp_ifc_event(in_dev);
2136#endif
2137	}
2138	spin_unlock_bh(&pmc->lock);
2139	return err;
2140}
2141
2142static void ip_mc_clear_src(struct ip_mc_list *pmc)
2143{
2144	struct ip_sf_list *tomb, *sources;
2145
2146	spin_lock_bh(&pmc->lock);
2147	tomb = pmc->tomb;
2148	pmc->tomb = NULL;
2149	sources = pmc->sources;
2150	pmc->sources = NULL;
2151	pmc->sfmode = MCAST_EXCLUDE;
2152	pmc->sfcount[MCAST_INCLUDE] = 0;
2153	pmc->sfcount[MCAST_EXCLUDE] = 1;
2154	spin_unlock_bh(&pmc->lock);
2155
2156	ip_sf_list_clear_all(tomb);
2157	ip_sf_list_clear_all(sources);
 
 
 
 
 
 
2158}
2159
2160/* Join a multicast group
2161 */
2162static int __ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr,
2163			      unsigned int mode)
2164{
2165	__be32 addr = imr->imr_multiaddr.s_addr;
2166	struct ip_mc_socklist *iml, *i;
2167	struct in_device *in_dev;
2168	struct inet_sock *inet = inet_sk(sk);
2169	struct net *net = sock_net(sk);
2170	int ifindex;
2171	int count = 0;
2172	int err;
2173
2174	ASSERT_RTNL();
2175
2176	if (!ipv4_is_multicast(addr))
2177		return -EINVAL;
2178
2179	in_dev = ip_mc_find_dev(net, imr);
2180
2181	if (!in_dev) {
2182		err = -ENODEV;
2183		goto done;
2184	}
2185
2186	err = -EADDRINUSE;
2187	ifindex = imr->imr_ifindex;
2188	for_each_pmc_rtnl(inet, i) {
2189		if (i->multi.imr_multiaddr.s_addr == addr &&
2190		    i->multi.imr_ifindex == ifindex)
2191			goto done;
2192		count++;
2193	}
2194	err = -ENOBUFS;
2195	if (count >= net->ipv4.sysctl_igmp_max_memberships)
2196		goto done;
2197	iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
2198	if (!iml)
2199		goto done;
2200
2201	memcpy(&iml->multi, imr, sizeof(*imr));
2202	iml->next_rcu = inet->mc_list;
2203	iml->sflist = NULL;
2204	iml->sfmode = mode;
2205	rcu_assign_pointer(inet->mc_list, iml);
2206	____ip_mc_inc_group(in_dev, addr, mode, GFP_KERNEL);
2207	err = 0;
2208done:
2209	return err;
2210}
2211
2212/* Join ASM (Any-Source Multicast) group
2213 */
2214int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
2215{
2216	return __ip_mc_join_group(sk, imr, MCAST_EXCLUDE);
2217}
2218EXPORT_SYMBOL(ip_mc_join_group);
2219
2220/* Join SSM (Source-Specific Multicast) group
2221 */
2222int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr,
2223			 unsigned int mode)
2224{
2225	return __ip_mc_join_group(sk, imr, mode);
2226}
2227
2228static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
2229			   struct in_device *in_dev)
2230{
2231	struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
2232	int err;
2233
2234	if (!psf) {
2235		/* any-source empty exclude case */
2236		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2237			iml->sfmode, 0, NULL, 0);
2238	}
2239	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2240			iml->sfmode, psf->sl_count, psf->sl_addr, 0);
2241	RCU_INIT_POINTER(iml->sflist, NULL);
2242	/* decrease mem now to avoid the memleak warning */
2243	atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc);
2244	kfree_rcu(psf, rcu);
2245	return err;
2246}
2247
2248int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
2249{
2250	struct inet_sock *inet = inet_sk(sk);
2251	struct ip_mc_socklist *iml;
2252	struct ip_mc_socklist __rcu **imlp;
2253	struct in_device *in_dev;
2254	struct net *net = sock_net(sk);
2255	__be32 group = imr->imr_multiaddr.s_addr;
2256	u32 ifindex;
2257	int ret = -EADDRNOTAVAIL;
2258
2259	ASSERT_RTNL();
2260
2261	in_dev = ip_mc_find_dev(net, imr);
2262	if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) {
2263		ret = -ENODEV;
2264		goto out;
2265	}
2266	ifindex = imr->imr_ifindex;
2267	for (imlp = &inet->mc_list;
2268	     (iml = rtnl_dereference(*imlp)) != NULL;
2269	     imlp = &iml->next_rcu) {
2270		if (iml->multi.imr_multiaddr.s_addr != group)
2271			continue;
2272		if (ifindex) {
2273			if (iml->multi.imr_ifindex != ifindex)
2274				continue;
2275		} else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
2276				iml->multi.imr_address.s_addr)
2277			continue;
2278
2279		(void) ip_mc_leave_src(sk, iml, in_dev);
2280
2281		*imlp = iml->next_rcu;
2282
2283		if (in_dev)
2284			ip_mc_dec_group(in_dev, group);
2285
2286		/* decrease mem now to avoid the memleak warning */
2287		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2288		kfree_rcu(iml, rcu);
2289		return 0;
2290	}
2291out:
2292	return ret;
2293}
2294EXPORT_SYMBOL(ip_mc_leave_group);
2295
2296int ip_mc_source(int add, int omode, struct sock *sk, struct
2297	ip_mreq_source *mreqs, int ifindex)
2298{
2299	int err;
2300	struct ip_mreqn imr;
2301	__be32 addr = mreqs->imr_multiaddr;
2302	struct ip_mc_socklist *pmc;
2303	struct in_device *in_dev = NULL;
2304	struct inet_sock *inet = inet_sk(sk);
2305	struct ip_sf_socklist *psl;
2306	struct net *net = sock_net(sk);
2307	int leavegroup = 0;
2308	int i, j, rv;
2309
2310	if (!ipv4_is_multicast(addr))
2311		return -EINVAL;
2312
2313	ASSERT_RTNL();
2314
2315	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
2316	imr.imr_address.s_addr = mreqs->imr_interface;
2317	imr.imr_ifindex = ifindex;
2318	in_dev = ip_mc_find_dev(net, &imr);
2319
2320	if (!in_dev) {
2321		err = -ENODEV;
2322		goto done;
2323	}
2324	err = -EADDRNOTAVAIL;
2325
2326	for_each_pmc_rtnl(inet, pmc) {
2327		if ((pmc->multi.imr_multiaddr.s_addr ==
2328		     imr.imr_multiaddr.s_addr) &&
2329		    (pmc->multi.imr_ifindex == imr.imr_ifindex))
2330			break;
2331	}
2332	if (!pmc) {		/* must have a prior join */
2333		err = -EINVAL;
2334		goto done;
2335	}
2336	/* if a source filter was set, must be the same mode as before */
2337	if (pmc->sflist) {
2338		if (pmc->sfmode != omode) {
2339			err = -EINVAL;
2340			goto done;
2341		}
2342	} else if (pmc->sfmode != omode) {
2343		/* allow mode switches for empty-set filters */
2344		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
2345		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
2346			NULL, 0);
2347		pmc->sfmode = omode;
2348	}
2349
2350	psl = rtnl_dereference(pmc->sflist);
2351	if (!add) {
2352		if (!psl)
2353			goto done;	/* err = -EADDRNOTAVAIL */
2354		rv = !0;
2355		for (i = 0; i < psl->sl_count; i++) {
2356			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2357				sizeof(__be32));
2358			if (rv == 0)
2359				break;
2360		}
2361		if (rv)		/* source not found */
2362			goto done;	/* err = -EADDRNOTAVAIL */
2363
2364		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2365		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
2366			leavegroup = 1;
2367			goto done;
2368		}
2369
2370		/* update the interface filter */
2371		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2372			&mreqs->imr_sourceaddr, 1);
2373
2374		for (j = i+1; j < psl->sl_count; j++)
2375			psl->sl_addr[j-1] = psl->sl_addr[j];
2376		psl->sl_count--;
2377		err = 0;
2378		goto done;
2379	}
2380	/* else, add a new source to the filter */
2381
2382	if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) {
2383		err = -ENOBUFS;
2384		goto done;
2385	}
2386	if (!psl || psl->sl_count == psl->sl_max) {
2387		struct ip_sf_socklist *newpsl;
2388		int count = IP_SFBLOCK;
2389
2390		if (psl)
2391			count += psl->sl_max;
2392		newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
2393		if (!newpsl) {
2394			err = -ENOBUFS;
2395			goto done;
2396		}
2397		newpsl->sl_max = count;
2398		newpsl->sl_count = count - IP_SFBLOCK;
2399		if (psl) {
2400			for (i = 0; i < psl->sl_count; i++)
2401				newpsl->sl_addr[i] = psl->sl_addr[i];
2402			/* decrease mem now to avoid the memleak warning */
2403			atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2404			kfree_rcu(psl, rcu);
2405		}
2406		rcu_assign_pointer(pmc->sflist, newpsl);
2407		psl = newpsl;
2408	}
2409	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
2410	for (i = 0; i < psl->sl_count; i++) {
2411		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2412			sizeof(__be32));
2413		if (rv == 0)
2414			break;
2415	}
2416	if (rv == 0)		/* address already there is an error */
2417		goto done;
2418	for (j = psl->sl_count-1; j >= i; j--)
2419		psl->sl_addr[j+1] = psl->sl_addr[j];
2420	psl->sl_addr[i] = mreqs->imr_sourceaddr;
2421	psl->sl_count++;
2422	err = 0;
2423	/* update the interface list */
2424	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2425		&mreqs->imr_sourceaddr, 1);
2426done:
2427	if (leavegroup)
2428		err = ip_mc_leave_group(sk, &imr);
2429	return err;
2430}
2431
2432int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2433{
2434	int err = 0;
2435	struct ip_mreqn	imr;
2436	__be32 addr = msf->imsf_multiaddr;
2437	struct ip_mc_socklist *pmc;
2438	struct in_device *in_dev;
2439	struct inet_sock *inet = inet_sk(sk);
2440	struct ip_sf_socklist *newpsl, *psl;
2441	struct net *net = sock_net(sk);
2442	int leavegroup = 0;
2443
2444	if (!ipv4_is_multicast(addr))
2445		return -EINVAL;
2446	if (msf->imsf_fmode != MCAST_INCLUDE &&
2447	    msf->imsf_fmode != MCAST_EXCLUDE)
2448		return -EINVAL;
2449
2450	ASSERT_RTNL();
2451
2452	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2453	imr.imr_address.s_addr = msf->imsf_interface;
2454	imr.imr_ifindex = ifindex;
2455	in_dev = ip_mc_find_dev(net, &imr);
2456
2457	if (!in_dev) {
2458		err = -ENODEV;
2459		goto done;
2460	}
2461
2462	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2463	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2464		leavegroup = 1;
2465		goto done;
2466	}
2467
2468	for_each_pmc_rtnl(inet, pmc) {
2469		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2470		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2471			break;
2472	}
2473	if (!pmc) {		/* must have a prior join */
2474		err = -EINVAL;
2475		goto done;
2476	}
2477	if (msf->imsf_numsrc) {
2478		newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2479							   GFP_KERNEL);
2480		if (!newpsl) {
2481			err = -ENOBUFS;
2482			goto done;
2483		}
2484		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2485		memcpy(newpsl->sl_addr, msf->imsf_slist,
2486			msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2487		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2488			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2489		if (err) {
2490			sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2491			goto done;
2492		}
2493	} else {
2494		newpsl = NULL;
2495		(void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2496				     msf->imsf_fmode, 0, NULL, 0);
2497	}
2498	psl = rtnl_dereference(pmc->sflist);
2499	if (psl) {
2500		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2501			psl->sl_count, psl->sl_addr, 0);
2502		/* decrease mem now to avoid the memleak warning */
2503		atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2504		kfree_rcu(psl, rcu);
2505	} else
2506		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2507			0, NULL, 0);
2508	rcu_assign_pointer(pmc->sflist, newpsl);
2509	pmc->sfmode = msf->imsf_fmode;
2510	err = 0;
2511done:
2512	if (leavegroup)
2513		err = ip_mc_leave_group(sk, &imr);
2514	return err;
2515}
2516
2517int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2518	struct ip_msfilter __user *optval, int __user *optlen)
2519{
2520	int err, len, count, copycount;
2521	struct ip_mreqn	imr;
2522	__be32 addr = msf->imsf_multiaddr;
2523	struct ip_mc_socklist *pmc;
2524	struct in_device *in_dev;
2525	struct inet_sock *inet = inet_sk(sk);
2526	struct ip_sf_socklist *psl;
2527	struct net *net = sock_net(sk);
2528
2529	ASSERT_RTNL();
2530
2531	if (!ipv4_is_multicast(addr))
2532		return -EINVAL;
2533
2534	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2535	imr.imr_address.s_addr = msf->imsf_interface;
2536	imr.imr_ifindex = 0;
2537	in_dev = ip_mc_find_dev(net, &imr);
2538
2539	if (!in_dev) {
2540		err = -ENODEV;
2541		goto done;
2542	}
2543	err = -EADDRNOTAVAIL;
2544
2545	for_each_pmc_rtnl(inet, pmc) {
2546		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2547		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2548			break;
2549	}
2550	if (!pmc)		/* must have a prior join */
2551		goto done;
2552	msf->imsf_fmode = pmc->sfmode;
2553	psl = rtnl_dereference(pmc->sflist);
2554	if (!psl) {
2555		len = 0;
2556		count = 0;
2557	} else {
2558		count = psl->sl_count;
2559	}
2560	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2561	len = copycount * sizeof(psl->sl_addr[0]);
2562	msf->imsf_numsrc = count;
2563	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2564	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2565		return -EFAULT;
2566	}
2567	if (len &&
2568	    copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2569		return -EFAULT;
2570	return 0;
2571done:
2572	return err;
2573}
2574
2575int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2576	struct sockaddr_storage __user *p)
2577{
2578	int i, count, copycount;
2579	struct sockaddr_in *psin;
2580	__be32 addr;
2581	struct ip_mc_socklist *pmc;
2582	struct inet_sock *inet = inet_sk(sk);
2583	struct ip_sf_socklist *psl;
2584
2585	ASSERT_RTNL();
2586
2587	psin = (struct sockaddr_in *)&gsf->gf_group;
2588	if (psin->sin_family != AF_INET)
2589		return -EINVAL;
2590	addr = psin->sin_addr.s_addr;
2591	if (!ipv4_is_multicast(addr))
2592		return -EINVAL;
2593
 
 
2594	for_each_pmc_rtnl(inet, pmc) {
2595		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2596		    pmc->multi.imr_ifindex == gsf->gf_interface)
2597			break;
2598	}
2599	if (!pmc)		/* must have a prior join */
2600		return -EADDRNOTAVAIL;
2601	gsf->gf_fmode = pmc->sfmode;
2602	psl = rtnl_dereference(pmc->sflist);
2603	count = psl ? psl->sl_count : 0;
2604	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2605	gsf->gf_numsrc = count;
2606	for (i = 0; i < copycount; i++, p++) {
 
 
 
 
2607		struct sockaddr_storage ss;
2608
2609		psin = (struct sockaddr_in *)&ss;
2610		memset(&ss, 0, sizeof(ss));
2611		psin->sin_family = AF_INET;
2612		psin->sin_addr.s_addr = psl->sl_addr[i];
2613		if (copy_to_user(p, &ss, sizeof(ss)))
2614			return -EFAULT;
2615	}
2616	return 0;
 
 
2617}
2618
2619/*
2620 * check if a multicast source filter allows delivery for a given <src,dst,intf>
2621 */
2622int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr,
2623		   int dif, int sdif)
2624{
2625	struct inet_sock *inet = inet_sk(sk);
2626	struct ip_mc_socklist *pmc;
2627	struct ip_sf_socklist *psl;
2628	int i;
2629	int ret;
2630
2631	ret = 1;
2632	if (!ipv4_is_multicast(loc_addr))
2633		goto out;
2634
2635	rcu_read_lock();
2636	for_each_pmc_rcu(inet, pmc) {
2637		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2638		    (pmc->multi.imr_ifindex == dif ||
2639		     (sdif && pmc->multi.imr_ifindex == sdif)))
2640			break;
2641	}
2642	ret = inet->mc_all;
2643	if (!pmc)
2644		goto unlock;
2645	psl = rcu_dereference(pmc->sflist);
2646	ret = (pmc->sfmode == MCAST_EXCLUDE);
2647	if (!psl)
2648		goto unlock;
2649
2650	for (i = 0; i < psl->sl_count; i++) {
2651		if (psl->sl_addr[i] == rmt_addr)
2652			break;
2653	}
2654	ret = 0;
2655	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2656		goto unlock;
2657	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2658		goto unlock;
2659	ret = 1;
2660unlock:
2661	rcu_read_unlock();
2662out:
2663	return ret;
2664}
2665
2666/*
2667 *	A socket is closing.
2668 */
2669
2670void ip_mc_drop_socket(struct sock *sk)
2671{
2672	struct inet_sock *inet = inet_sk(sk);
2673	struct ip_mc_socklist *iml;
2674	struct net *net = sock_net(sk);
2675
2676	if (!inet->mc_list)
2677		return;
2678
2679	rtnl_lock();
2680	while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2681		struct in_device *in_dev;
2682
2683		inet->mc_list = iml->next_rcu;
2684		in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2685		(void) ip_mc_leave_src(sk, iml, in_dev);
2686		if (in_dev)
2687			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2688		/* decrease mem now to avoid the memleak warning */
2689		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2690		kfree_rcu(iml, rcu);
2691	}
2692	rtnl_unlock();
2693}
2694
2695/* called with rcu_read_lock() */
2696int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto)
2697{
2698	struct ip_mc_list *im;
2699	struct ip_mc_list __rcu **mc_hash;
2700	struct ip_sf_list *psf;
2701	int rv = 0;
2702
2703	mc_hash = rcu_dereference(in_dev->mc_hash);
2704	if (mc_hash) {
2705		u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
2706
2707		for (im = rcu_dereference(mc_hash[hash]);
2708		     im != NULL;
2709		     im = rcu_dereference(im->next_hash)) {
2710			if (im->multiaddr == mc_addr)
2711				break;
2712		}
2713	} else {
2714		for_each_pmc_rcu(in_dev, im) {
2715			if (im->multiaddr == mc_addr)
2716				break;
2717		}
2718	}
2719	if (im && proto == IPPROTO_IGMP) {
2720		rv = 1;
2721	} else if (im) {
2722		if (src_addr) {
2723			spin_lock_bh(&im->lock);
2724			for (psf = im->sources; psf; psf = psf->sf_next) {
2725				if (psf->sf_inaddr == src_addr)
2726					break;
2727			}
2728			if (psf)
2729				rv = psf->sf_count[MCAST_INCLUDE] ||
2730					psf->sf_count[MCAST_EXCLUDE] !=
2731					im->sfcount[MCAST_EXCLUDE];
2732			else
2733				rv = im->sfcount[MCAST_EXCLUDE] != 0;
2734			spin_unlock_bh(&im->lock);
2735		} else
2736			rv = 1; /* unspecified source; tentatively allow */
2737	}
2738	return rv;
2739}
2740
2741#if defined(CONFIG_PROC_FS)
2742struct igmp_mc_iter_state {
2743	struct seq_net_private p;
2744	struct net_device *dev;
2745	struct in_device *in_dev;
2746};
2747
2748#define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2749
2750static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2751{
2752	struct net *net = seq_file_net(seq);
2753	struct ip_mc_list *im = NULL;
2754	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2755
2756	state->in_dev = NULL;
2757	for_each_netdev_rcu(net, state->dev) {
2758		struct in_device *in_dev;
2759
2760		in_dev = __in_dev_get_rcu(state->dev);
2761		if (!in_dev)
2762			continue;
2763		im = rcu_dereference(in_dev->mc_list);
2764		if (im) {
2765			state->in_dev = in_dev;
2766			break;
2767		}
2768	}
2769	return im;
2770}
2771
2772static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2773{
2774	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2775
2776	im = rcu_dereference(im->next_rcu);
2777	while (!im) {
2778		state->dev = next_net_device_rcu(state->dev);
2779		if (!state->dev) {
2780			state->in_dev = NULL;
2781			break;
2782		}
2783		state->in_dev = __in_dev_get_rcu(state->dev);
2784		if (!state->in_dev)
2785			continue;
2786		im = rcu_dereference(state->in_dev->mc_list);
2787	}
2788	return im;
2789}
2790
2791static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2792{
2793	struct ip_mc_list *im = igmp_mc_get_first(seq);
2794	if (im)
2795		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2796			--pos;
2797	return pos ? NULL : im;
2798}
2799
2800static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2801	__acquires(rcu)
2802{
2803	rcu_read_lock();
2804	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2805}
2806
2807static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2808{
2809	struct ip_mc_list *im;
2810	if (v == SEQ_START_TOKEN)
2811		im = igmp_mc_get_first(seq);
2812	else
2813		im = igmp_mc_get_next(seq, v);
2814	++*pos;
2815	return im;
2816}
2817
2818static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2819	__releases(rcu)
2820{
2821	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2822
2823	state->in_dev = NULL;
2824	state->dev = NULL;
2825	rcu_read_unlock();
2826}
2827
2828static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2829{
2830	if (v == SEQ_START_TOKEN)
2831		seq_puts(seq,
2832			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2833	else {
2834		struct ip_mc_list *im = (struct ip_mc_list *)v;
2835		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2836		char   *querier;
2837		long delta;
2838
2839#ifdef CONFIG_IP_MULTICAST
2840		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2841			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2842			  "V3";
2843#else
2844		querier = "NONE";
2845#endif
2846
2847		if (rcu_access_pointer(state->in_dev->mc_list) == im) {
2848			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2849				   state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2850		}
2851
2852		delta = im->timer.expires - jiffies;
2853		seq_printf(seq,
2854			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2855			   im->multiaddr, im->users,
2856			   im->tm_running,
2857			   im->tm_running ? jiffies_delta_to_clock_t(delta) : 0,
2858			   im->reporter);
2859	}
2860	return 0;
2861}
2862
2863static const struct seq_operations igmp_mc_seq_ops = {
2864	.start	=	igmp_mc_seq_start,
2865	.next	=	igmp_mc_seq_next,
2866	.stop	=	igmp_mc_seq_stop,
2867	.show	=	igmp_mc_seq_show,
2868};
2869
 
 
 
 
 
 
 
 
 
 
 
 
 
2870struct igmp_mcf_iter_state {
2871	struct seq_net_private p;
2872	struct net_device *dev;
2873	struct in_device *idev;
2874	struct ip_mc_list *im;
2875};
2876
2877#define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2878
2879static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2880{
2881	struct net *net = seq_file_net(seq);
2882	struct ip_sf_list *psf = NULL;
2883	struct ip_mc_list *im = NULL;
2884	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2885
2886	state->idev = NULL;
2887	state->im = NULL;
2888	for_each_netdev_rcu(net, state->dev) {
2889		struct in_device *idev;
2890		idev = __in_dev_get_rcu(state->dev);
2891		if (unlikely(!idev))
2892			continue;
2893		im = rcu_dereference(idev->mc_list);
2894		if (likely(im)) {
2895			spin_lock_bh(&im->lock);
2896			psf = im->sources;
2897			if (likely(psf)) {
2898				state->im = im;
2899				state->idev = idev;
2900				break;
2901			}
2902			spin_unlock_bh(&im->lock);
2903		}
2904	}
2905	return psf;
2906}
2907
2908static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2909{
2910	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2911
2912	psf = psf->sf_next;
2913	while (!psf) {
2914		spin_unlock_bh(&state->im->lock);
2915		state->im = state->im->next;
2916		while (!state->im) {
2917			state->dev = next_net_device_rcu(state->dev);
2918			if (!state->dev) {
2919				state->idev = NULL;
2920				goto out;
2921			}
2922			state->idev = __in_dev_get_rcu(state->dev);
2923			if (!state->idev)
2924				continue;
2925			state->im = rcu_dereference(state->idev->mc_list);
2926		}
2927		if (!state->im)
2928			break;
2929		spin_lock_bh(&state->im->lock);
2930		psf = state->im->sources;
2931	}
2932out:
2933	return psf;
2934}
2935
2936static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2937{
2938	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2939	if (psf)
2940		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2941			--pos;
2942	return pos ? NULL : psf;
2943}
2944
2945static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2946	__acquires(rcu)
2947{
2948	rcu_read_lock();
2949	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2950}
2951
2952static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2953{
2954	struct ip_sf_list *psf;
2955	if (v == SEQ_START_TOKEN)
2956		psf = igmp_mcf_get_first(seq);
2957	else
2958		psf = igmp_mcf_get_next(seq, v);
2959	++*pos;
2960	return psf;
2961}
2962
2963static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2964	__releases(rcu)
2965{
2966	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2967	if (likely(state->im)) {
2968		spin_unlock_bh(&state->im->lock);
2969		state->im = NULL;
2970	}
2971	state->idev = NULL;
2972	state->dev = NULL;
2973	rcu_read_unlock();
2974}
2975
2976static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2977{
2978	struct ip_sf_list *psf = (struct ip_sf_list *)v;
2979	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2980
2981	if (v == SEQ_START_TOKEN) {
2982		seq_puts(seq, "Idx Device        MCA        SRC    INC    EXC\n");
2983	} else {
2984		seq_printf(seq,
2985			   "%3d %6.6s 0x%08x "
2986			   "0x%08x %6lu %6lu\n",
2987			   state->dev->ifindex, state->dev->name,
2988			   ntohl(state->im->multiaddr),
2989			   ntohl(psf->sf_inaddr),
2990			   psf->sf_count[MCAST_INCLUDE],
2991			   psf->sf_count[MCAST_EXCLUDE]);
2992	}
2993	return 0;
2994}
2995
2996static const struct seq_operations igmp_mcf_seq_ops = {
2997	.start	=	igmp_mcf_seq_start,
2998	.next	=	igmp_mcf_seq_next,
2999	.stop	=	igmp_mcf_seq_stop,
3000	.show	=	igmp_mcf_seq_show,
3001};
3002
 
 
 
 
 
 
 
 
 
 
 
 
 
3003static int __net_init igmp_net_init(struct net *net)
3004{
3005	struct proc_dir_entry *pde;
3006	int err;
3007
3008	pde = proc_create_net("igmp", 0444, net->proc_net, &igmp_mc_seq_ops,
3009			sizeof(struct igmp_mc_iter_state));
3010	if (!pde)
3011		goto out_igmp;
3012	pde = proc_create_net("mcfilter", 0444, net->proc_net,
3013			&igmp_mcf_seq_ops, sizeof(struct igmp_mcf_iter_state));
3014	if (!pde)
3015		goto out_mcfilter;
3016	err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET,
3017				   SOCK_DGRAM, 0, net);
3018	if (err < 0) {
3019		pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n",
3020		       err);
3021		goto out_sock;
3022	}
3023
3024	return 0;
3025
3026out_sock:
3027	remove_proc_entry("mcfilter", net->proc_net);
3028out_mcfilter:
3029	remove_proc_entry("igmp", net->proc_net);
3030out_igmp:
3031	return -ENOMEM;
3032}
3033
3034static void __net_exit igmp_net_exit(struct net *net)
3035{
3036	remove_proc_entry("mcfilter", net->proc_net);
3037	remove_proc_entry("igmp", net->proc_net);
3038	inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk);
3039}
3040
3041static struct pernet_operations igmp_net_ops = {
3042	.init = igmp_net_init,
3043	.exit = igmp_net_exit,
3044};
3045#endif
3046
3047static int igmp_netdev_event(struct notifier_block *this,
3048			     unsigned long event, void *ptr)
3049{
3050	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3051	struct in_device *in_dev;
3052
3053	switch (event) {
3054	case NETDEV_RESEND_IGMP:
3055		in_dev = __in_dev_get_rtnl(dev);
3056		if (in_dev)
3057			ip_mc_rejoin_groups(in_dev);
3058		break;
3059	default:
3060		break;
3061	}
3062	return NOTIFY_DONE;
3063}
3064
3065static struct notifier_block igmp_notifier = {
3066	.notifier_call = igmp_netdev_event,
3067};
3068
3069int __init igmp_mc_init(void)
3070{
3071#if defined(CONFIG_PROC_FS)
3072	int err;
3073
3074	err = register_pernet_subsys(&igmp_net_ops);
3075	if (err)
3076		return err;
3077	err = register_netdevice_notifier(&igmp_notifier);
3078	if (err)
3079		goto reg_notif_fail;
3080	return 0;
3081
3082reg_notif_fail:
3083	unregister_pernet_subsys(&igmp_net_ops);
3084	return err;
3085#else
3086	return register_netdevice_notifier(&igmp_notifier);
3087#endif
3088}
v4.17
 
   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 <linux/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#include <linux/byteorder/generic.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 <net/inet_common.h>
 102#include <linux/netfilter_ipv4.h>
 103#ifdef CONFIG_IP_MROUTE
 104#include <linux/mroute.h>
 105#endif
 106#ifdef CONFIG_PROC_FS
 107#include <linux/proc_fs.h>
 108#include <linux/seq_file.h>
 109#endif
 110
 111#ifdef CONFIG_IP_MULTICAST
 112/* Parameter names and values are taken from igmp-v2-06 draft */
 113
 114#define IGMP_V1_ROUTER_PRESENT_TIMEOUT		(400*HZ)
 115#define IGMP_V2_ROUTER_PRESENT_TIMEOUT		(400*HZ)
 116#define IGMP_V2_UNSOLICITED_REPORT_INTERVAL	(10*HZ)
 117#define IGMP_V3_UNSOLICITED_REPORT_INTERVAL	(1*HZ)
 118#define IGMP_QUERY_RESPONSE_INTERVAL		(10*HZ)
 119#define IGMP_QUERY_ROBUSTNESS_VARIABLE		2
 120
 121
 122#define IGMP_INITIAL_REPORT_DELAY		(1)
 123
 124/* IGMP_INITIAL_REPORT_DELAY is not from IGMP specs!
 125 * IGMP specs require to report membership immediately after
 126 * joining a group, but we delay the first report by a
 127 * small interval. It seems more natural and still does not
 128 * contradict to specs provided this delay is small enough.
 129 */
 130
 131#define IGMP_V1_SEEN(in_dev) \
 132	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \
 133	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \
 134	 ((in_dev)->mr_v1_seen && \
 135	  time_before(jiffies, (in_dev)->mr_v1_seen)))
 136#define IGMP_V2_SEEN(in_dev) \
 137	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \
 138	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \
 139	 ((in_dev)->mr_v2_seen && \
 140	  time_before(jiffies, (in_dev)->mr_v2_seen)))
 141
 142static int unsolicited_report_interval(struct in_device *in_dev)
 143{
 144	int interval_ms, interval_jiffies;
 145
 146	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 147		interval_ms = IN_DEV_CONF_GET(
 148			in_dev,
 149			IGMPV2_UNSOLICITED_REPORT_INTERVAL);
 150	else /* v3 */
 151		interval_ms = IN_DEV_CONF_GET(
 152			in_dev,
 153			IGMPV3_UNSOLICITED_REPORT_INTERVAL);
 154
 155	interval_jiffies = msecs_to_jiffies(interval_ms);
 156
 157	/* _timer functions can't handle a delay of 0 jiffies so ensure
 158	 *  we always return a positive value.
 159	 */
 160	if (interval_jiffies <= 0)
 161		interval_jiffies = 1;
 162	return interval_jiffies;
 163}
 164
 165static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im);
 
 166static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im);
 167static void igmpv3_clear_delrec(struct in_device *in_dev);
 168static int sf_setstate(struct ip_mc_list *pmc);
 169static void sf_markstate(struct ip_mc_list *pmc);
 170#endif
 171static void ip_mc_clear_src(struct ip_mc_list *pmc);
 172static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
 173			 int sfcount, __be32 *psfsrc, int delta);
 174
 175static void ip_ma_put(struct ip_mc_list *im)
 176{
 177	if (refcount_dec_and_test(&im->refcnt)) {
 178		in_dev_put(im->interface);
 179		kfree_rcu(im, rcu);
 180	}
 181}
 182
 183#define for_each_pmc_rcu(in_dev, pmc)				\
 184	for (pmc = rcu_dereference(in_dev->mc_list);		\
 185	     pmc != NULL;					\
 186	     pmc = rcu_dereference(pmc->next_rcu))
 187
 188#define for_each_pmc_rtnl(in_dev, pmc)				\
 189	for (pmc = rtnl_dereference(in_dev->mc_list);		\
 190	     pmc != NULL;					\
 191	     pmc = rtnl_dereference(pmc->next_rcu))
 192
 
 
 
 
 
 
 
 
 
 
 
 193#ifdef CONFIG_IP_MULTICAST
 194
 195/*
 196 *	Timer management
 197 */
 198
 199static void igmp_stop_timer(struct ip_mc_list *im)
 200{
 201	spin_lock_bh(&im->lock);
 202	if (del_timer(&im->timer))
 203		refcount_dec(&im->refcnt);
 204	im->tm_running = 0;
 205	im->reporter = 0;
 206	im->unsolicit_count = 0;
 207	spin_unlock_bh(&im->lock);
 208}
 209
 210/* It must be called with locked im->lock */
 211static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
 212{
 213	int tv = prandom_u32() % max_delay;
 214
 215	im->tm_running = 1;
 216	if (!mod_timer(&im->timer, jiffies+tv+2))
 217		refcount_inc(&im->refcnt);
 218}
 219
 220static void igmp_gq_start_timer(struct in_device *in_dev)
 221{
 222	int tv = prandom_u32() % in_dev->mr_maxdelay;
 223	unsigned long exp = jiffies + tv + 2;
 224
 225	if (in_dev->mr_gq_running &&
 226	    time_after_eq(exp, (in_dev->mr_gq_timer).expires))
 227		return;
 228
 229	in_dev->mr_gq_running = 1;
 230	if (!mod_timer(&in_dev->mr_gq_timer, exp))
 231		in_dev_hold(in_dev);
 232}
 233
 234static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
 235{
 236	int tv = prandom_u32() % delay;
 237
 238	if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
 239		in_dev_hold(in_dev);
 240}
 241
 242static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
 243{
 244	spin_lock_bh(&im->lock);
 245	im->unsolicit_count = 0;
 246	if (del_timer(&im->timer)) {
 247		if ((long)(im->timer.expires-jiffies) < max_delay) {
 248			add_timer(&im->timer);
 249			im->tm_running = 1;
 250			spin_unlock_bh(&im->lock);
 251			return;
 252		}
 253		refcount_dec(&im->refcnt);
 254	}
 255	igmp_start_timer(im, max_delay);
 256	spin_unlock_bh(&im->lock);
 257}
 258
 259
 260/*
 261 *	Send an IGMP report.
 262 */
 263
 264#define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
 265
 266
 267static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
 268	int gdeleted, int sdeleted)
 269{
 270	switch (type) {
 271	case IGMPV3_MODE_IS_INCLUDE:
 272	case IGMPV3_MODE_IS_EXCLUDE:
 273		if (gdeleted || sdeleted)
 274			return 0;
 275		if (!(pmc->gsquery && !psf->sf_gsresp)) {
 276			if (pmc->sfmode == MCAST_INCLUDE)
 277				return 1;
 278			/* don't include if this source is excluded
 279			 * in all filters
 280			 */
 281			if (psf->sf_count[MCAST_INCLUDE])
 282				return type == IGMPV3_MODE_IS_INCLUDE;
 283			return pmc->sfcount[MCAST_EXCLUDE] ==
 284				psf->sf_count[MCAST_EXCLUDE];
 285		}
 286		return 0;
 287	case IGMPV3_CHANGE_TO_INCLUDE:
 288		if (gdeleted || sdeleted)
 289			return 0;
 290		return psf->sf_count[MCAST_INCLUDE] != 0;
 291	case IGMPV3_CHANGE_TO_EXCLUDE:
 292		if (gdeleted || sdeleted)
 293			return 0;
 294		if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
 295		    psf->sf_count[MCAST_INCLUDE])
 296			return 0;
 297		return pmc->sfcount[MCAST_EXCLUDE] ==
 298			psf->sf_count[MCAST_EXCLUDE];
 299	case IGMPV3_ALLOW_NEW_SOURCES:
 300		if (gdeleted || !psf->sf_crcount)
 301			return 0;
 302		return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
 303	case IGMPV3_BLOCK_OLD_SOURCES:
 304		if (pmc->sfmode == MCAST_INCLUDE)
 305			return gdeleted || (psf->sf_crcount && sdeleted);
 306		return psf->sf_crcount && !gdeleted && !sdeleted;
 307	}
 308	return 0;
 309}
 310
 311static int
 312igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
 313{
 314	struct ip_sf_list *psf;
 315	int scount = 0;
 316
 317	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 318		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
 319			continue;
 320		scount++;
 321	}
 322	return scount;
 323}
 324
 325/* source address selection per RFC 3376 section 4.2.13 */
 326static __be32 igmpv3_get_srcaddr(struct net_device *dev,
 327				 const struct flowi4 *fl4)
 328{
 329	struct in_device *in_dev = __in_dev_get_rcu(dev);
 
 330
 331	if (!in_dev)
 332		return htonl(INADDR_ANY);
 333
 334	for_ifa(in_dev) {
 335		if (fl4->saddr == ifa->ifa_local)
 336			return fl4->saddr;
 337	} endfor_ifa(in_dev);
 338
 339	return htonl(INADDR_ANY);
 340}
 341
 342static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
 343{
 344	struct sk_buff *skb;
 345	struct rtable *rt;
 346	struct iphdr *pip;
 347	struct igmpv3_report *pig;
 348	struct net *net = dev_net(dev);
 349	struct flowi4 fl4;
 350	int hlen = LL_RESERVED_SPACE(dev);
 351	int tlen = dev->needed_tailroom;
 352	unsigned int size = mtu;
 353
 354	while (1) {
 355		skb = alloc_skb(size + hlen + tlen,
 356				GFP_ATOMIC | __GFP_NOWARN);
 357		if (skb)
 358			break;
 359		size >>= 1;
 360		if (size < 256)
 361			return NULL;
 362	}
 363	skb->priority = TC_PRIO_CONTROL;
 364
 365	rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0,
 366				   0, 0,
 367				   IPPROTO_IGMP, 0, dev->ifindex);
 368	if (IS_ERR(rt)) {
 369		kfree_skb(skb);
 370		return NULL;
 371	}
 372
 373	skb_dst_set(skb, &rt->dst);
 374	skb->dev = dev;
 375
 376	skb_reserve(skb, hlen);
 377	skb_tailroom_reserve(skb, mtu, tlen);
 378
 379	skb_reset_network_header(skb);
 380	pip = ip_hdr(skb);
 381	skb_put(skb, sizeof(struct iphdr) + 4);
 382
 383	pip->version  = 4;
 384	pip->ihl      = (sizeof(struct iphdr)+4)>>2;
 385	pip->tos      = 0xc0;
 386	pip->frag_off = htons(IP_DF);
 387	pip->ttl      = 1;
 388	pip->daddr    = fl4.daddr;
 389
 390	rcu_read_lock();
 391	pip->saddr    = igmpv3_get_srcaddr(dev, &fl4);
 392	rcu_read_unlock();
 393
 394	pip->protocol = IPPROTO_IGMP;
 395	pip->tot_len  = 0;	/* filled in later */
 396	ip_select_ident(net, skb, NULL);
 397	((u8 *)&pip[1])[0] = IPOPT_RA;
 398	((u8 *)&pip[1])[1] = 4;
 399	((u8 *)&pip[1])[2] = 0;
 400	((u8 *)&pip[1])[3] = 0;
 401
 402	skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
 403	skb_put(skb, sizeof(*pig));
 404	pig = igmpv3_report_hdr(skb);
 405	pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
 406	pig->resv1 = 0;
 407	pig->csum = 0;
 408	pig->resv2 = 0;
 409	pig->ngrec = 0;
 410	return skb;
 411}
 412
 413static int igmpv3_sendpack(struct sk_buff *skb)
 414{
 415	struct igmphdr *pig = igmp_hdr(skb);
 416	const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
 417
 418	pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
 419
 420	return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
 421}
 422
 423static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
 424{
 425	return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
 426}
 427
 428static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
 429	int type, struct igmpv3_grec **ppgr, unsigned int mtu)
 430{
 431	struct net_device *dev = pmc->interface->dev;
 432	struct igmpv3_report *pih;
 433	struct igmpv3_grec *pgr;
 434
 435	if (!skb) {
 436		skb = igmpv3_newpack(dev, mtu);
 437		if (!skb)
 438			return NULL;
 439	}
 440	pgr = skb_put(skb, sizeof(struct igmpv3_grec));
 441	pgr->grec_type = type;
 442	pgr->grec_auxwords = 0;
 443	pgr->grec_nsrcs = 0;
 444	pgr->grec_mca = pmc->multiaddr;
 445	pih = igmpv3_report_hdr(skb);
 446	pih->ngrec = htons(ntohs(pih->ngrec)+1);
 447	*ppgr = pgr;
 448	return skb;
 449}
 450
 451#define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
 452
 453static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
 454	int type, int gdeleted, int sdeleted)
 455{
 456	struct net_device *dev = pmc->interface->dev;
 457	struct net *net = dev_net(dev);
 458	struct igmpv3_report *pih;
 459	struct igmpv3_grec *pgr = NULL;
 460	struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
 461	int scount, stotal, first, isquery, truncate;
 462	unsigned int mtu;
 463
 464	if (pmc->multiaddr == IGMP_ALL_HOSTS)
 465		return skb;
 466	if (ipv4_is_local_multicast(pmc->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
 467		return skb;
 468
 469	mtu = READ_ONCE(dev->mtu);
 470	if (mtu < IPV4_MIN_MTU)
 471		return skb;
 472
 473	isquery = type == IGMPV3_MODE_IS_INCLUDE ||
 474		  type == IGMPV3_MODE_IS_EXCLUDE;
 475	truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
 476		    type == IGMPV3_CHANGE_TO_EXCLUDE;
 477
 478	stotal = scount = 0;
 479
 480	psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
 481
 482	if (!*psf_list)
 483		goto empty_source;
 484
 485	pih = skb ? igmpv3_report_hdr(skb) : NULL;
 486
 487	/* EX and TO_EX get a fresh packet, if needed */
 488	if (truncate) {
 489		if (pih && pih->ngrec &&
 490		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
 491			if (skb)
 492				igmpv3_sendpack(skb);
 493			skb = igmpv3_newpack(dev, mtu);
 494		}
 495	}
 496	first = 1;
 497	psf_prev = NULL;
 498	for (psf = *psf_list; psf; psf = psf_next) {
 499		__be32 *psrc;
 500
 501		psf_next = psf->sf_next;
 502
 503		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
 504			psf_prev = psf;
 505			continue;
 506		}
 507
 508		/* Based on RFC3376 5.1. Should not send source-list change
 509		 * records when there is a filter mode change.
 510		 */
 511		if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) ||
 512		     (!gdeleted && pmc->crcount)) &&
 513		    (type == IGMPV3_ALLOW_NEW_SOURCES ||
 514		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount)
 515			goto decrease_sf_crcount;
 516
 517		/* clear marks on query responses */
 518		if (isquery)
 519			psf->sf_gsresp = 0;
 520
 521		if (AVAILABLE(skb) < sizeof(__be32) +
 522		    first*sizeof(struct igmpv3_grec)) {
 523			if (truncate && !first)
 524				break;	 /* truncate these */
 525			if (pgr)
 526				pgr->grec_nsrcs = htons(scount);
 527			if (skb)
 528				igmpv3_sendpack(skb);
 529			skb = igmpv3_newpack(dev, mtu);
 530			first = 1;
 531			scount = 0;
 532		}
 533		if (first) {
 534			skb = add_grhead(skb, pmc, type, &pgr, mtu);
 535			first = 0;
 536		}
 537		if (!skb)
 538			return NULL;
 539		psrc = skb_put(skb, sizeof(__be32));
 540		*psrc = psf->sf_inaddr;
 541		scount++; stotal++;
 542		if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
 543		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
 544decrease_sf_crcount:
 545			psf->sf_crcount--;
 546			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
 547				if (psf_prev)
 548					psf_prev->sf_next = psf->sf_next;
 549				else
 550					*psf_list = psf->sf_next;
 551				kfree(psf);
 552				continue;
 553			}
 554		}
 555		psf_prev = psf;
 556	}
 557
 558empty_source:
 559	if (!stotal) {
 560		if (type == IGMPV3_ALLOW_NEW_SOURCES ||
 561		    type == IGMPV3_BLOCK_OLD_SOURCES)
 562			return skb;
 563		if (pmc->crcount || isquery) {
 564			/* make sure we have room for group header */
 565			if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) {
 566				igmpv3_sendpack(skb);
 567				skb = NULL; /* add_grhead will get a new one */
 568			}
 569			skb = add_grhead(skb, pmc, type, &pgr, mtu);
 570		}
 571	}
 572	if (pgr)
 573		pgr->grec_nsrcs = htons(scount);
 574
 575	if (isquery)
 576		pmc->gsquery = 0;	/* clear query state on report */
 577	return skb;
 578}
 579
 580static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
 581{
 582	struct sk_buff *skb = NULL;
 583	struct net *net = dev_net(in_dev->dev);
 584	int type;
 585
 586	if (!pmc) {
 587		rcu_read_lock();
 588		for_each_pmc_rcu(in_dev, pmc) {
 589			if (pmc->multiaddr == IGMP_ALL_HOSTS)
 590				continue;
 591			if (ipv4_is_local_multicast(pmc->multiaddr) &&
 592			     !net->ipv4.sysctl_igmp_llm_reports)
 593				continue;
 594			spin_lock_bh(&pmc->lock);
 595			if (pmc->sfcount[MCAST_EXCLUDE])
 596				type = IGMPV3_MODE_IS_EXCLUDE;
 597			else
 598				type = IGMPV3_MODE_IS_INCLUDE;
 599			skb = add_grec(skb, pmc, type, 0, 0);
 600			spin_unlock_bh(&pmc->lock);
 601		}
 602		rcu_read_unlock();
 603	} else {
 604		spin_lock_bh(&pmc->lock);
 605		if (pmc->sfcount[MCAST_EXCLUDE])
 606			type = IGMPV3_MODE_IS_EXCLUDE;
 607		else
 608			type = IGMPV3_MODE_IS_INCLUDE;
 609		skb = add_grec(skb, pmc, type, 0, 0);
 610		spin_unlock_bh(&pmc->lock);
 611	}
 612	if (!skb)
 613		return 0;
 614	return igmpv3_sendpack(skb);
 615}
 616
 617/*
 618 * remove zero-count source records from a source filter list
 619 */
 620static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
 621{
 622	struct ip_sf_list *psf_prev, *psf_next, *psf;
 623
 624	psf_prev = NULL;
 625	for (psf = *ppsf; psf; psf = psf_next) {
 626		psf_next = psf->sf_next;
 627		if (psf->sf_crcount == 0) {
 628			if (psf_prev)
 629				psf_prev->sf_next = psf->sf_next;
 630			else
 631				*ppsf = psf->sf_next;
 632			kfree(psf);
 633		} else
 634			psf_prev = psf;
 635	}
 636}
 637
 
 
 
 
 
 
 
 638static void igmpv3_send_cr(struct in_device *in_dev)
 639{
 640	struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
 641	struct sk_buff *skb = NULL;
 642	int type, dtype;
 643
 644	rcu_read_lock();
 645	spin_lock_bh(&in_dev->mc_tomb_lock);
 646
 647	/* deleted MCA's */
 648	pmc_prev = NULL;
 649	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) {
 650		pmc_next = pmc->next;
 651		if (pmc->sfmode == MCAST_INCLUDE) {
 652			type = IGMPV3_BLOCK_OLD_SOURCES;
 653			dtype = IGMPV3_BLOCK_OLD_SOURCES;
 654			skb = add_grec(skb, pmc, type, 1, 0);
 655			skb = add_grec(skb, pmc, dtype, 1, 1);
 656		}
 657		if (pmc->crcount) {
 658			if (pmc->sfmode == MCAST_EXCLUDE) {
 659				type = IGMPV3_CHANGE_TO_INCLUDE;
 660				skb = add_grec(skb, pmc, type, 1, 0);
 661			}
 662			pmc->crcount--;
 663			if (pmc->crcount == 0) {
 664				igmpv3_clear_zeros(&pmc->tomb);
 665				igmpv3_clear_zeros(&pmc->sources);
 666			}
 667		}
 668		if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
 669			if (pmc_prev)
 670				pmc_prev->next = pmc_next;
 671			else
 672				in_dev->mc_tomb = pmc_next;
 673			in_dev_put(pmc->interface);
 674			kfree(pmc);
 675		} else
 676			pmc_prev = pmc;
 677	}
 678	spin_unlock_bh(&in_dev->mc_tomb_lock);
 679
 680	/* change recs */
 681	for_each_pmc_rcu(in_dev, pmc) {
 682		spin_lock_bh(&pmc->lock);
 683		if (pmc->sfcount[MCAST_EXCLUDE]) {
 684			type = IGMPV3_BLOCK_OLD_SOURCES;
 685			dtype = IGMPV3_ALLOW_NEW_SOURCES;
 686		} else {
 687			type = IGMPV3_ALLOW_NEW_SOURCES;
 688			dtype = IGMPV3_BLOCK_OLD_SOURCES;
 689		}
 690		skb = add_grec(skb, pmc, type, 0, 0);
 691		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
 692
 693		/* filter mode changes */
 694		if (pmc->crcount) {
 695			if (pmc->sfmode == MCAST_EXCLUDE)
 696				type = IGMPV3_CHANGE_TO_EXCLUDE;
 697			else
 698				type = IGMPV3_CHANGE_TO_INCLUDE;
 699			skb = add_grec(skb, pmc, type, 0, 0);
 700			pmc->crcount--;
 701		}
 702		spin_unlock_bh(&pmc->lock);
 703	}
 704	rcu_read_unlock();
 705
 706	if (!skb)
 707		return;
 708	(void) igmpv3_sendpack(skb);
 709}
 710
 711static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
 712	int type)
 713{
 714	struct sk_buff *skb;
 715	struct iphdr *iph;
 716	struct igmphdr *ih;
 717	struct rtable *rt;
 718	struct net_device *dev = in_dev->dev;
 719	struct net *net = dev_net(dev);
 720	__be32	group = pmc ? pmc->multiaddr : 0;
 721	struct flowi4 fl4;
 722	__be32	dst;
 723	int hlen, tlen;
 724
 725	if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
 726		return igmpv3_send_report(in_dev, pmc);
 727
 728	if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
 729		return 0;
 730
 731	if (type == IGMP_HOST_LEAVE_MESSAGE)
 732		dst = IGMP_ALL_ROUTER;
 733	else
 734		dst = group;
 735
 736	rt = ip_route_output_ports(net, &fl4, NULL, dst, 0,
 737				   0, 0,
 738				   IPPROTO_IGMP, 0, dev->ifindex);
 739	if (IS_ERR(rt))
 740		return -1;
 741
 742	hlen = LL_RESERVED_SPACE(dev);
 743	tlen = dev->needed_tailroom;
 744	skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC);
 745	if (!skb) {
 746		ip_rt_put(rt);
 747		return -1;
 748	}
 749	skb->priority = TC_PRIO_CONTROL;
 750
 751	skb_dst_set(skb, &rt->dst);
 752
 753	skb_reserve(skb, hlen);
 754
 755	skb_reset_network_header(skb);
 756	iph = ip_hdr(skb);
 757	skb_put(skb, sizeof(struct iphdr) + 4);
 758
 759	iph->version  = 4;
 760	iph->ihl      = (sizeof(struct iphdr)+4)>>2;
 761	iph->tos      = 0xc0;
 762	iph->frag_off = htons(IP_DF);
 763	iph->ttl      = 1;
 764	iph->daddr    = dst;
 765	iph->saddr    = fl4.saddr;
 766	iph->protocol = IPPROTO_IGMP;
 767	ip_select_ident(net, skb, NULL);
 768	((u8 *)&iph[1])[0] = IPOPT_RA;
 769	((u8 *)&iph[1])[1] = 4;
 770	((u8 *)&iph[1])[2] = 0;
 771	((u8 *)&iph[1])[3] = 0;
 772
 773	ih = skb_put(skb, sizeof(struct igmphdr));
 774	ih->type = type;
 775	ih->code = 0;
 776	ih->csum = 0;
 777	ih->group = group;
 778	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 779
 780	return ip_local_out(net, skb->sk, skb);
 781}
 782
 783static void igmp_gq_timer_expire(struct timer_list *t)
 784{
 785	struct in_device *in_dev = from_timer(in_dev, t, mr_gq_timer);
 786
 787	in_dev->mr_gq_running = 0;
 788	igmpv3_send_report(in_dev, NULL);
 789	in_dev_put(in_dev);
 790}
 791
 792static void igmp_ifc_timer_expire(struct timer_list *t)
 793{
 794	struct in_device *in_dev = from_timer(in_dev, t, mr_ifc_timer);
 
 795
 796	igmpv3_send_cr(in_dev);
 797	if (in_dev->mr_ifc_count) {
 798		in_dev->mr_ifc_count--;
 
 
 
 
 
 
 799		igmp_ifc_start_timer(in_dev,
 800				     unsolicited_report_interval(in_dev));
 801	}
 802	in_dev_put(in_dev);
 803}
 804
 805static void igmp_ifc_event(struct in_device *in_dev)
 806{
 807	struct net *net = dev_net(in_dev->dev);
 808	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 809		return;
 810	in_dev->mr_ifc_count = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
 811	igmp_ifc_start_timer(in_dev, 1);
 812}
 813
 814
 815static void igmp_timer_expire(struct timer_list *t)
 816{
 817	struct ip_mc_list *im = from_timer(im, t, timer);
 818	struct in_device *in_dev = im->interface;
 819
 820	spin_lock(&im->lock);
 821	im->tm_running = 0;
 822
 823	if (im->unsolicit_count) {
 824		im->unsolicit_count--;
 825		igmp_start_timer(im, unsolicited_report_interval(in_dev));
 826	}
 827	im->reporter = 1;
 828	spin_unlock(&im->lock);
 829
 830	if (IGMP_V1_SEEN(in_dev))
 831		igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
 832	else if (IGMP_V2_SEEN(in_dev))
 833		igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
 834	else
 835		igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
 836
 837	ip_ma_put(im);
 838}
 839
 840/* mark EXCLUDE-mode sources */
 841static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 842{
 843	struct ip_sf_list *psf;
 844	int i, scount;
 845
 846	scount = 0;
 847	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 848		if (scount == nsrcs)
 849			break;
 850		for (i = 0; i < nsrcs; i++) {
 851			/* skip inactive filters */
 852			if (psf->sf_count[MCAST_INCLUDE] ||
 853			    pmc->sfcount[MCAST_EXCLUDE] !=
 854			    psf->sf_count[MCAST_EXCLUDE])
 855				break;
 856			if (srcs[i] == psf->sf_inaddr) {
 857				scount++;
 858				break;
 859			}
 860		}
 861	}
 862	pmc->gsquery = 0;
 863	if (scount == nsrcs)	/* all sources excluded */
 864		return 0;
 865	return 1;
 866}
 867
 868static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 869{
 870	struct ip_sf_list *psf;
 871	int i, scount;
 872
 873	if (pmc->sfmode == MCAST_EXCLUDE)
 874		return igmp_xmarksources(pmc, nsrcs, srcs);
 875
 876	/* mark INCLUDE-mode sources */
 877	scount = 0;
 878	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 879		if (scount == nsrcs)
 880			break;
 881		for (i = 0; i < nsrcs; i++)
 882			if (srcs[i] == psf->sf_inaddr) {
 883				psf->sf_gsresp = 1;
 884				scount++;
 885				break;
 886			}
 887	}
 888	if (!scount) {
 889		pmc->gsquery = 0;
 890		return 0;
 891	}
 892	pmc->gsquery = 1;
 893	return 1;
 894}
 895
 896/* return true if packet was dropped */
 897static bool igmp_heard_report(struct in_device *in_dev, __be32 group)
 898{
 899	struct ip_mc_list *im;
 900	struct net *net = dev_net(in_dev->dev);
 901
 902	/* Timers are only set for non-local groups */
 903
 904	if (group == IGMP_ALL_HOSTS)
 905		return false;
 906	if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
 907		return false;
 908
 909	rcu_read_lock();
 910	for_each_pmc_rcu(in_dev, im) {
 911		if (im->multiaddr == group) {
 912			igmp_stop_timer(im);
 913			break;
 914		}
 915	}
 916	rcu_read_unlock();
 917	return false;
 918}
 919
 920/* return true if packet was dropped */
 921static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
 922	int len)
 923{
 924	struct igmphdr 		*ih = igmp_hdr(skb);
 925	struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
 926	struct ip_mc_list	*im;
 927	__be32			group = ih->group;
 928	int			max_delay;
 929	int			mark = 0;
 930	struct net		*net = dev_net(in_dev->dev);
 931
 932
 933	if (len == 8) {
 934		if (ih->code == 0) {
 935			/* Alas, old v1 router presents here. */
 936
 937			max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 938			in_dev->mr_v1_seen = jiffies +
 939				IGMP_V1_ROUTER_PRESENT_TIMEOUT;
 
 940			group = 0;
 941		} else {
 942			/* v2 router present */
 943			max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
 944			in_dev->mr_v2_seen = jiffies +
 945				IGMP_V2_ROUTER_PRESENT_TIMEOUT;
 
 946		}
 947		/* cancel the interface change timer */
 948		in_dev->mr_ifc_count = 0;
 949		if (del_timer(&in_dev->mr_ifc_timer))
 950			__in_dev_put(in_dev);
 951		/* clear deleted report items */
 952		igmpv3_clear_delrec(in_dev);
 953	} else if (len < 12) {
 954		return true;	/* ignore bogus packet; freed by caller */
 955	} else if (IGMP_V1_SEEN(in_dev)) {
 956		/* This is a v3 query with v1 queriers present */
 957		max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 958		group = 0;
 959	} else if (IGMP_V2_SEEN(in_dev)) {
 960		/* this is a v3 query with v2 queriers present;
 961		 * Interpretation of the max_delay code is problematic here.
 962		 * A real v2 host would use ih_code directly, while v3 has a
 963		 * different encoding. We use the v3 encoding as more likely
 964		 * to be intended in a v3 query.
 965		 */
 966		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 967		if (!max_delay)
 968			max_delay = 1;	/* can't mod w/ 0 */
 969	} else { /* v3 */
 970		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
 971			return true;
 972
 973		ih3 = igmpv3_query_hdr(skb);
 974		if (ih3->nsrcs) {
 975			if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
 976					   + ntohs(ih3->nsrcs)*sizeof(__be32)))
 977				return true;
 978			ih3 = igmpv3_query_hdr(skb);
 979		}
 980
 981		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 982		if (!max_delay)
 983			max_delay = 1;	/* can't mod w/ 0 */
 984		in_dev->mr_maxdelay = max_delay;
 985		if (ih3->qrv)
 986			in_dev->mr_qrv = ih3->qrv;
 
 
 
 
 
 
 
 
 
 
 
 
 
 987		if (!group) { /* general query */
 988			if (ih3->nsrcs)
 989				return true;	/* no sources allowed */
 990			igmp_gq_start_timer(in_dev);
 991			return false;
 992		}
 993		/* mark sources to include, if group & source-specific */
 994		mark = ih3->nsrcs != 0;
 995	}
 996
 997	/*
 998	 * - Start the timers in all of our membership records
 999	 *   that the query applies to for the interface on
1000	 *   which the query arrived excl. those that belong
1001	 *   to a "local" group (224.0.0.X)
1002	 * - For timers already running check if they need to
1003	 *   be reset.
1004	 * - Use the igmp->igmp_code field as the maximum
1005	 *   delay possible
1006	 */
1007	rcu_read_lock();
1008	for_each_pmc_rcu(in_dev, im) {
1009		int changed;
1010
1011		if (group && group != im->multiaddr)
1012			continue;
1013		if (im->multiaddr == IGMP_ALL_HOSTS)
1014			continue;
1015		if (ipv4_is_local_multicast(im->multiaddr) &&
1016		    !net->ipv4.sysctl_igmp_llm_reports)
1017			continue;
1018		spin_lock_bh(&im->lock);
1019		if (im->tm_running)
1020			im->gsquery = im->gsquery && mark;
1021		else
1022			im->gsquery = mark;
1023		changed = !im->gsquery ||
1024			igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
1025		spin_unlock_bh(&im->lock);
1026		if (changed)
1027			igmp_mod_timer(im, max_delay);
1028	}
1029	rcu_read_unlock();
1030	return false;
1031}
1032
1033/* called in rcu_read_lock() section */
1034int igmp_rcv(struct sk_buff *skb)
1035{
1036	/* This basically follows the spec line by line -- see RFC1112 */
1037	struct igmphdr *ih;
1038	struct net_device *dev = skb->dev;
1039	struct in_device *in_dev;
1040	int len = skb->len;
1041	bool dropped = true;
1042
1043	if (netif_is_l3_master(dev)) {
1044		dev = dev_get_by_index_rcu(dev_net(dev), IPCB(skb)->iif);
1045		if (!dev)
1046			goto drop;
1047	}
1048
1049	in_dev = __in_dev_get_rcu(dev);
1050	if (!in_dev)
1051		goto drop;
1052
1053	if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
1054		goto drop;
1055
1056	if (skb_checksum_simple_validate(skb))
1057		goto drop;
1058
1059	ih = igmp_hdr(skb);
1060	switch (ih->type) {
1061	case IGMP_HOST_MEMBERSHIP_QUERY:
1062		dropped = igmp_heard_query(in_dev, skb, len);
1063		break;
1064	case IGMP_HOST_MEMBERSHIP_REPORT:
1065	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1066		/* Is it our report looped back? */
1067		if (rt_is_output_route(skb_rtable(skb)))
1068			break;
1069		/* don't rely on MC router hearing unicast reports */
1070		if (skb->pkt_type == PACKET_MULTICAST ||
1071		    skb->pkt_type == PACKET_BROADCAST)
1072			dropped = igmp_heard_report(in_dev, ih->group);
1073		break;
1074	case IGMP_PIM:
1075#ifdef CONFIG_IP_PIMSM_V1
1076		return pim_rcv_v1(skb);
1077#endif
1078	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1079	case IGMP_DVMRP:
1080	case IGMP_TRACE:
1081	case IGMP_HOST_LEAVE_MESSAGE:
1082	case IGMP_MTRACE:
1083	case IGMP_MTRACE_RESP:
1084		break;
1085	default:
1086		break;
1087	}
1088
1089drop:
1090	if (dropped)
1091		kfree_skb(skb);
1092	else
1093		consume_skb(skb);
1094	return 0;
1095}
1096
1097#endif
1098
1099
1100/*
1101 *	Add a filter to a device
1102 */
1103
1104static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1105{
1106	char buf[MAX_ADDR_LEN];
1107	struct net_device *dev = in_dev->dev;
1108
1109	/* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1110	   We will get multicast token leakage, when IFF_MULTICAST
1111	   is changed. This check should be done in ndo_set_rx_mode
1112	   routine. Something sort of:
1113	   if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1114	   --ANK
1115	   */
1116	if (arp_mc_map(addr, buf, dev, 0) == 0)
1117		dev_mc_add(dev, buf);
1118}
1119
1120/*
1121 *	Remove a filter from a device
1122 */
1123
1124static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1125{
1126	char buf[MAX_ADDR_LEN];
1127	struct net_device *dev = in_dev->dev;
1128
1129	if (arp_mc_map(addr, buf, dev, 0) == 0)
1130		dev_mc_del(dev, buf);
1131}
1132
1133#ifdef CONFIG_IP_MULTICAST
1134/*
1135 * deleted ip_mc_list manipulation
1136 */
1137static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
 
1138{
1139	struct ip_mc_list *pmc;
1140	struct net *net = dev_net(in_dev->dev);
1141
1142	/* this is an "ip_mc_list" for convenience; only the fields below
1143	 * are actually used. In particular, the refcnt and users are not
1144	 * used for management of the delete list. Using the same structure
1145	 * for deleted items allows change reports to use common code with
1146	 * non-deleted or query-response MCA's.
1147	 */
1148	pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
1149	if (!pmc)
1150		return;
1151	spin_lock_init(&pmc->lock);
1152	spin_lock_bh(&im->lock);
1153	pmc->interface = im->interface;
1154	in_dev_hold(in_dev);
1155	pmc->multiaddr = im->multiaddr;
1156	pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1157	pmc->sfmode = im->sfmode;
1158	if (pmc->sfmode == MCAST_INCLUDE) {
1159		struct ip_sf_list *psf;
1160
1161		pmc->tomb = im->tomb;
1162		pmc->sources = im->sources;
1163		im->tomb = im->sources = NULL;
1164		for (psf = pmc->sources; psf; psf = psf->sf_next)
1165			psf->sf_crcount = pmc->crcount;
1166	}
1167	spin_unlock_bh(&im->lock);
1168
1169	spin_lock_bh(&in_dev->mc_tomb_lock);
1170	pmc->next = in_dev->mc_tomb;
1171	in_dev->mc_tomb = pmc;
1172	spin_unlock_bh(&in_dev->mc_tomb_lock);
1173}
1174
1175/*
1176 * restore ip_mc_list deleted records
1177 */
1178static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1179{
1180	struct ip_mc_list *pmc, *pmc_prev;
1181	struct ip_sf_list *psf;
1182	struct net *net = dev_net(in_dev->dev);
1183	__be32 multiaddr = im->multiaddr;
1184
1185	spin_lock_bh(&in_dev->mc_tomb_lock);
1186	pmc_prev = NULL;
1187	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) {
1188		if (pmc->multiaddr == multiaddr)
1189			break;
1190		pmc_prev = pmc;
1191	}
1192	if (pmc) {
1193		if (pmc_prev)
1194			pmc_prev->next = pmc->next;
1195		else
1196			in_dev->mc_tomb = pmc->next;
1197	}
1198	spin_unlock_bh(&in_dev->mc_tomb_lock);
1199
1200	spin_lock_bh(&im->lock);
1201	if (pmc) {
1202		im->interface = pmc->interface;
1203		im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1204		im->sfmode = pmc->sfmode;
1205		if (pmc->sfmode == MCAST_INCLUDE) {
1206			im->tomb = pmc->tomb;
1207			im->sources = pmc->sources;
1208			for (psf = im->sources; psf; psf = psf->sf_next)
1209				psf->sf_crcount = im->crcount;
 
 
1210		}
1211		in_dev_put(pmc->interface);
1212		kfree(pmc);
1213	}
1214	spin_unlock_bh(&im->lock);
1215}
1216
1217/*
1218 * flush ip_mc_list deleted records
1219 */
1220static void igmpv3_clear_delrec(struct in_device *in_dev)
1221{
1222	struct ip_mc_list *pmc, *nextpmc;
1223
1224	spin_lock_bh(&in_dev->mc_tomb_lock);
1225	pmc = in_dev->mc_tomb;
1226	in_dev->mc_tomb = NULL;
1227	spin_unlock_bh(&in_dev->mc_tomb_lock);
1228
1229	for (; pmc; pmc = nextpmc) {
1230		nextpmc = pmc->next;
1231		ip_mc_clear_src(pmc);
1232		in_dev_put(pmc->interface);
1233		kfree(pmc);
1234	}
1235	/* clear dead sources, too */
1236	rcu_read_lock();
1237	for_each_pmc_rcu(in_dev, pmc) {
1238		struct ip_sf_list *psf, *psf_next;
1239
1240		spin_lock_bh(&pmc->lock);
1241		psf = pmc->tomb;
1242		pmc->tomb = NULL;
1243		spin_unlock_bh(&pmc->lock);
1244		for (; psf; psf = psf_next) {
1245			psf_next = psf->sf_next;
1246			kfree(psf);
1247		}
1248	}
1249	rcu_read_unlock();
1250}
1251#endif
1252
1253static void igmp_group_dropped(struct ip_mc_list *im)
1254{
1255	struct in_device *in_dev = im->interface;
1256#ifdef CONFIG_IP_MULTICAST
1257	struct net *net = dev_net(in_dev->dev);
1258	int reporter;
1259#endif
1260
1261	if (im->loaded) {
1262		im->loaded = 0;
1263		ip_mc_filter_del(in_dev, im->multiaddr);
1264	}
1265
1266#ifdef CONFIG_IP_MULTICAST
1267	if (im->multiaddr == IGMP_ALL_HOSTS)
1268		return;
1269	if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1270		return;
1271
1272	reporter = im->reporter;
1273	igmp_stop_timer(im);
1274
1275	if (!in_dev->dead) {
1276		if (IGMP_V1_SEEN(in_dev))
1277			return;
1278		if (IGMP_V2_SEEN(in_dev)) {
1279			if (reporter)
1280				igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1281			return;
1282		}
1283		/* IGMPv3 */
1284		igmpv3_add_delrec(in_dev, im);
1285
1286		igmp_ifc_event(in_dev);
1287	}
1288#endif
1289}
1290
 
 
 
 
 
1291static void igmp_group_added(struct ip_mc_list *im)
1292{
1293	struct in_device *in_dev = im->interface;
1294#ifdef CONFIG_IP_MULTICAST
1295	struct net *net = dev_net(in_dev->dev);
1296#endif
1297
1298	if (im->loaded == 0) {
1299		im->loaded = 1;
1300		ip_mc_filter_add(in_dev, im->multiaddr);
1301	}
1302
1303#ifdef CONFIG_IP_MULTICAST
1304	if (im->multiaddr == IGMP_ALL_HOSTS)
1305		return;
1306	if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1307		return;
1308
1309	if (in_dev->dead)
1310		return;
 
 
1311	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1312		spin_lock_bh(&im->lock);
1313		igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY);
1314		spin_unlock_bh(&im->lock);
1315		return;
1316	}
1317	/* else, v3 */
1318
1319	im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
 
 
 
 
 
 
1320	igmp_ifc_event(in_dev);
1321#endif
1322}
1323
1324
1325/*
1326 *	Multicast list managers
1327 */
1328
1329static u32 ip_mc_hash(const struct ip_mc_list *im)
1330{
1331	return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
1332}
1333
1334static void ip_mc_hash_add(struct in_device *in_dev,
1335			   struct ip_mc_list *im)
1336{
1337	struct ip_mc_list __rcu **mc_hash;
1338	u32 hash;
1339
1340	mc_hash = rtnl_dereference(in_dev->mc_hash);
1341	if (mc_hash) {
1342		hash = ip_mc_hash(im);
1343		im->next_hash = mc_hash[hash];
1344		rcu_assign_pointer(mc_hash[hash], im);
1345		return;
1346	}
1347
1348	/* do not use a hash table for small number of items */
1349	if (in_dev->mc_count < 4)
1350		return;
1351
1352	mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
1353			  GFP_KERNEL);
1354	if (!mc_hash)
1355		return;
1356
1357	for_each_pmc_rtnl(in_dev, im) {
1358		hash = ip_mc_hash(im);
1359		im->next_hash = mc_hash[hash];
1360		RCU_INIT_POINTER(mc_hash[hash], im);
1361	}
1362
1363	rcu_assign_pointer(in_dev->mc_hash, mc_hash);
1364}
1365
1366static void ip_mc_hash_remove(struct in_device *in_dev,
1367			      struct ip_mc_list *im)
1368{
1369	struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
1370	struct ip_mc_list *aux;
1371
1372	if (!mc_hash)
1373		return;
1374	mc_hash += ip_mc_hash(im);
1375	while ((aux = rtnl_dereference(*mc_hash)) != im)
1376		mc_hash = &aux->next_hash;
1377	*mc_hash = im->next_hash;
1378}
1379
1380
1381/*
1382 *	A socket has joined a multicast group on device dev.
1383 */
1384
1385void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1386{
1387	struct ip_mc_list *im;
1388#ifdef CONFIG_IP_MULTICAST
1389	struct net *net = dev_net(in_dev->dev);
1390#endif
1391
1392	ASSERT_RTNL();
1393
1394	for_each_pmc_rtnl(in_dev, im) {
1395		if (im->multiaddr == addr) {
1396			im->users++;
1397			ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1398			goto out;
1399		}
1400	}
1401
1402	im = kzalloc(sizeof(*im), GFP_KERNEL);
1403	if (!im)
1404		goto out;
1405
1406	im->users = 1;
1407	im->interface = in_dev;
1408	in_dev_hold(in_dev);
1409	im->multiaddr = addr;
1410	/* initial mode is (EX, empty) */
1411	im->sfmode = MCAST_EXCLUDE;
1412	im->sfcount[MCAST_EXCLUDE] = 1;
1413	refcount_set(&im->refcnt, 1);
1414	spin_lock_init(&im->lock);
1415#ifdef CONFIG_IP_MULTICAST
1416	timer_setup(&im->timer, igmp_timer_expire, 0);
1417	im->unsolicit_count = net->ipv4.sysctl_igmp_qrv;
1418#endif
1419
1420	im->next_rcu = in_dev->mc_list;
1421	in_dev->mc_count++;
1422	rcu_assign_pointer(in_dev->mc_list, im);
1423
1424	ip_mc_hash_add(in_dev, im);
1425
1426#ifdef CONFIG_IP_MULTICAST
1427	igmpv3_del_delrec(in_dev, im);
1428#endif
1429	igmp_group_added(im);
1430	if (!in_dev->dead)
1431		ip_rt_multicast_event(in_dev);
1432out:
1433	return;
1434}
 
 
 
 
 
 
 
 
 
 
 
1435EXPORT_SYMBOL(ip_mc_inc_group);
1436
1437static int ip_mc_check_iphdr(struct sk_buff *skb)
1438{
1439	const struct iphdr *iph;
1440	unsigned int len;
1441	unsigned int offset = skb_network_offset(skb) + sizeof(*iph);
1442
1443	if (!pskb_may_pull(skb, offset))
1444		return -EINVAL;
1445
1446	iph = ip_hdr(skb);
1447
1448	if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph))
1449		return -EINVAL;
1450
1451	offset += ip_hdrlen(skb) - sizeof(*iph);
1452
1453	if (!pskb_may_pull(skb, offset))
1454		return -EINVAL;
1455
1456	iph = ip_hdr(skb);
1457
1458	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1459		return -EINVAL;
1460
1461	len = skb_network_offset(skb) + ntohs(iph->tot_len);
1462	if (skb->len < len || len < offset)
1463		return -EINVAL;
1464
1465	skb_set_transport_header(skb, offset);
1466
1467	return 0;
1468}
1469
1470static int ip_mc_check_igmp_reportv3(struct sk_buff *skb)
1471{
1472	unsigned int len = skb_transport_offset(skb);
1473
1474	len += sizeof(struct igmpv3_report);
1475
1476	return pskb_may_pull(skb, len) ? 0 : -EINVAL;
1477}
1478
1479static int ip_mc_check_igmp_query(struct sk_buff *skb)
1480{
1481	unsigned int len = skb_transport_offset(skb);
1482
1483	len += sizeof(struct igmphdr);
1484	if (skb->len < len)
1485		return -EINVAL;
1486
1487	/* IGMPv{1,2}? */
1488	if (skb->len != len) {
1489		/* or IGMPv3? */
1490		len += sizeof(struct igmpv3_query) - sizeof(struct igmphdr);
1491		if (skb->len < len || !pskb_may_pull(skb, len))
 
 
 
1492			return -EINVAL;
1493	}
1494
1495	/* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1496	 * all-systems destination addresses (224.0.0.1) for general queries
1497	 */
1498	if (!igmp_hdr(skb)->group &&
1499	    ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP))
1500		return -EINVAL;
1501
1502	return 0;
1503}
1504
1505static int ip_mc_check_igmp_msg(struct sk_buff *skb)
1506{
1507	switch (igmp_hdr(skb)->type) {
1508	case IGMP_HOST_LEAVE_MESSAGE:
1509	case IGMP_HOST_MEMBERSHIP_REPORT:
1510	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1511		/* fall through */
1512		return 0;
1513	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1514		return ip_mc_check_igmp_reportv3(skb);
1515	case IGMP_HOST_MEMBERSHIP_QUERY:
1516		return ip_mc_check_igmp_query(skb);
1517	default:
1518		return -ENOMSG;
1519	}
1520}
1521
1522static inline __sum16 ip_mc_validate_checksum(struct sk_buff *skb)
1523{
1524	return skb_checksum_simple_validate(skb);
1525}
1526
1527static int __ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
1528
1529{
 
 
1530	struct sk_buff *skb_chk;
1531	unsigned int transport_len;
1532	unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr);
1533	int ret = -EINVAL;
1534
1535	transport_len = ntohs(ip_hdr(skb)->tot_len) - ip_hdrlen(skb);
 
1536
1537	skb_chk = skb_checksum_trimmed(skb, transport_len,
1538				       ip_mc_validate_checksum);
1539	if (!skb_chk)
1540		goto err;
1541
1542	if (!pskb_may_pull(skb_chk, len))
1543		goto err;
1544
1545	ret = ip_mc_check_igmp_msg(skb_chk);
1546	if (ret)
1547		goto err;
1548
1549	if (skb_trimmed)
1550		*skb_trimmed = skb_chk;
1551	/* free now unneeded clone */
1552	else if (skb_chk != skb)
1553		kfree_skb(skb_chk);
1554
1555	ret = 0;
1556
1557err:
1558	if (ret && skb_chk && skb_chk != skb)
1559		kfree_skb(skb_chk);
1560
1561	return ret;
1562}
1563
1564/**
1565 * ip_mc_check_igmp - checks whether this is a sane IGMP packet
1566 * @skb: the skb to validate
1567 * @skb_trimmed: to store an skb pointer trimmed to IPv4 packet tail (optional)
1568 *
1569 * Checks whether an IPv4 packet is a valid IGMP packet. If so sets
1570 * skb transport header accordingly and returns zero.
1571 *
1572 * -EINVAL: A broken packet was detected, i.e. it violates some internet
1573 *  standard
1574 * -ENOMSG: IP header validation succeeded but it is not an IGMP packet.
1575 * -ENOMEM: A memory allocation failure happened.
1576 *
1577 * Optionally, an skb pointer might be provided via skb_trimmed (or set it
1578 * to NULL): After parsing an IGMP packet successfully it will point to
1579 * an skb which has its tail aligned to the IP packet end. This might
1580 * either be the originally provided skb or a trimmed, cloned version if
1581 * the skb frame had data beyond the IP packet. A cloned skb allows us
1582 * to leave the original skb and its full frame unchanged (which might be
1583 * desirable for layer 2 frame jugglers).
1584 *
1585 * Caller needs to set the skb network header and free any returned skb if it
1586 * differs from the provided skb.
1587 */
1588int ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
1589{
1590	int ret = ip_mc_check_iphdr(skb);
1591
1592	if (ret < 0)
1593		return ret;
1594
1595	if (ip_hdr(skb)->protocol != IPPROTO_IGMP)
1596		return -ENOMSG;
1597
1598	return __ip_mc_check_igmp(skb, skb_trimmed);
 
 
 
 
1599}
1600EXPORT_SYMBOL(ip_mc_check_igmp);
1601
1602/*
1603 *	Resend IGMP JOIN report; used by netdev notifier.
1604 */
1605static void ip_mc_rejoin_groups(struct in_device *in_dev)
1606{
1607#ifdef CONFIG_IP_MULTICAST
1608	struct ip_mc_list *im;
1609	int type;
1610	struct net *net = dev_net(in_dev->dev);
1611
1612	ASSERT_RTNL();
1613
1614	for_each_pmc_rtnl(in_dev, im) {
1615		if (im->multiaddr == IGMP_ALL_HOSTS)
1616			continue;
1617		if (ipv4_is_local_multicast(im->multiaddr) &&
1618		    !net->ipv4.sysctl_igmp_llm_reports)
1619			continue;
1620
1621		/* a failover is happening and switches
1622		 * must be notified immediately
1623		 */
1624		if (IGMP_V1_SEEN(in_dev))
1625			type = IGMP_HOST_MEMBERSHIP_REPORT;
1626		else if (IGMP_V2_SEEN(in_dev))
1627			type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1628		else
1629			type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1630		igmp_send_report(in_dev, im, type);
1631	}
1632#endif
1633}
1634
1635/*
1636 *	A socket has left a multicast group on device dev
1637 */
1638
1639void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
1640{
1641	struct ip_mc_list *i;
1642	struct ip_mc_list __rcu **ip;
1643
1644	ASSERT_RTNL();
1645
1646	for (ip = &in_dev->mc_list;
1647	     (i = rtnl_dereference(*ip)) != NULL;
1648	     ip = &i->next_rcu) {
1649		if (i->multiaddr == addr) {
1650			if (--i->users == 0) {
1651				ip_mc_hash_remove(in_dev, i);
1652				*ip = i->next_rcu;
1653				in_dev->mc_count--;
1654				igmp_group_dropped(i);
1655				ip_mc_clear_src(i);
1656
1657				if (!in_dev->dead)
1658					ip_rt_multicast_event(in_dev);
1659
1660				ip_ma_put(i);
1661				return;
1662			}
1663			break;
1664		}
1665	}
1666}
1667EXPORT_SYMBOL(ip_mc_dec_group);
1668
1669/* Device changing type */
1670
1671void ip_mc_unmap(struct in_device *in_dev)
1672{
1673	struct ip_mc_list *pmc;
1674
1675	ASSERT_RTNL();
1676
1677	for_each_pmc_rtnl(in_dev, pmc)
1678		igmp_group_dropped(pmc);
1679}
1680
1681void ip_mc_remap(struct in_device *in_dev)
1682{
1683	struct ip_mc_list *pmc;
1684
1685	ASSERT_RTNL();
1686
1687	for_each_pmc_rtnl(in_dev, pmc) {
1688#ifdef CONFIG_IP_MULTICAST
1689		igmpv3_del_delrec(in_dev, pmc);
1690#endif
1691		igmp_group_added(pmc);
1692	}
1693}
1694
1695/* Device going down */
1696
1697void ip_mc_down(struct in_device *in_dev)
1698{
1699	struct ip_mc_list *pmc;
1700
1701	ASSERT_RTNL();
1702
1703	for_each_pmc_rtnl(in_dev, pmc)
1704		igmp_group_dropped(pmc);
1705
1706#ifdef CONFIG_IP_MULTICAST
1707	in_dev->mr_ifc_count = 0;
1708	if (del_timer(&in_dev->mr_ifc_timer))
1709		__in_dev_put(in_dev);
1710	in_dev->mr_gq_running = 0;
1711	if (del_timer(&in_dev->mr_gq_timer))
1712		__in_dev_put(in_dev);
1713#endif
1714
1715	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1716}
1717
1718void ip_mc_init_dev(struct in_device *in_dev)
 
1719{
1720#ifdef CONFIG_IP_MULTICAST
1721	struct net *net = dev_net(in_dev->dev);
 
 
 
 
 
 
 
 
 
1722#endif
 
 
 
1723	ASSERT_RTNL();
1724
1725#ifdef CONFIG_IP_MULTICAST
1726	timer_setup(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 0);
1727	timer_setup(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 0);
1728	in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1729#endif
 
1730
1731	spin_lock_init(&in_dev->mc_tomb_lock);
1732}
1733
1734/* Device going up */
1735
1736void ip_mc_up(struct in_device *in_dev)
1737{
1738	struct ip_mc_list *pmc;
1739#ifdef CONFIG_IP_MULTICAST
1740	struct net *net = dev_net(in_dev->dev);
1741#endif
1742
1743	ASSERT_RTNL();
1744
1745#ifdef CONFIG_IP_MULTICAST
1746	in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1747#endif
1748	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1749
1750	for_each_pmc_rtnl(in_dev, pmc) {
1751#ifdef CONFIG_IP_MULTICAST
1752		igmpv3_del_delrec(in_dev, pmc);
1753#endif
1754		igmp_group_added(pmc);
1755	}
1756}
1757
1758/*
1759 *	Device is about to be destroyed: clean up.
1760 */
1761
1762void ip_mc_destroy_dev(struct in_device *in_dev)
1763{
1764	struct ip_mc_list *i;
1765
1766	ASSERT_RTNL();
1767
1768	/* Deactivate timers */
1769	ip_mc_down(in_dev);
1770#ifdef CONFIG_IP_MULTICAST
1771	igmpv3_clear_delrec(in_dev);
1772#endif
1773
1774	while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1775		in_dev->mc_list = i->next_rcu;
1776		in_dev->mc_count--;
 
1777		ip_ma_put(i);
1778	}
1779}
1780
1781/* RTNL is locked */
1782static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1783{
1784	struct net_device *dev = NULL;
1785	struct in_device *idev = NULL;
1786
1787	if (imr->imr_ifindex) {
1788		idev = inetdev_by_index(net, imr->imr_ifindex);
1789		return idev;
1790	}
1791	if (imr->imr_address.s_addr) {
1792		dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1793		if (!dev)
1794			return NULL;
1795	}
1796
1797	if (!dev) {
1798		struct rtable *rt = ip_route_output(net,
1799						    imr->imr_multiaddr.s_addr,
1800						    0, 0, 0);
1801		if (!IS_ERR(rt)) {
1802			dev = rt->dst.dev;
1803			ip_rt_put(rt);
1804		}
1805	}
1806	if (dev) {
1807		imr->imr_ifindex = dev->ifindex;
1808		idev = __in_dev_get_rtnl(dev);
1809	}
1810	return idev;
1811}
1812
1813/*
1814 *	Join a socket to a group
1815 */
1816
1817static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1818	__be32 *psfsrc)
1819{
1820	struct ip_sf_list *psf, *psf_prev;
1821	int rv = 0;
1822
1823	psf_prev = NULL;
1824	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1825		if (psf->sf_inaddr == *psfsrc)
1826			break;
1827		psf_prev = psf;
1828	}
1829	if (!psf || psf->sf_count[sfmode] == 0) {
1830		/* source filter not found, or count wrong =>  bug */
1831		return -ESRCH;
1832	}
1833	psf->sf_count[sfmode]--;
1834	if (psf->sf_count[sfmode] == 0) {
1835		ip_rt_multicast_event(pmc->interface);
1836	}
1837	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1838#ifdef CONFIG_IP_MULTICAST
1839		struct in_device *in_dev = pmc->interface;
1840		struct net *net = dev_net(in_dev->dev);
1841#endif
1842
1843		/* no more filters for this source */
1844		if (psf_prev)
1845			psf_prev->sf_next = psf->sf_next;
1846		else
1847			pmc->sources = psf->sf_next;
1848#ifdef CONFIG_IP_MULTICAST
1849		if (psf->sf_oldin &&
1850		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1851			psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1852			psf->sf_next = pmc->tomb;
1853			pmc->tomb = psf;
1854			rv = 1;
1855		} else
1856#endif
1857			kfree(psf);
1858	}
1859	return rv;
1860}
1861
1862#ifndef CONFIG_IP_MULTICAST
1863#define igmp_ifc_event(x)	do { } while (0)
1864#endif
1865
1866static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1867			 int sfcount, __be32 *psfsrc, int delta)
1868{
1869	struct ip_mc_list *pmc;
1870	int	changerec = 0;
1871	int	i, err;
1872
1873	if (!in_dev)
1874		return -ENODEV;
1875	rcu_read_lock();
1876	for_each_pmc_rcu(in_dev, pmc) {
1877		if (*pmca == pmc->multiaddr)
1878			break;
1879	}
1880	if (!pmc) {
1881		/* MCA not found?? bug */
1882		rcu_read_unlock();
1883		return -ESRCH;
1884	}
1885	spin_lock_bh(&pmc->lock);
1886	rcu_read_unlock();
1887#ifdef CONFIG_IP_MULTICAST
1888	sf_markstate(pmc);
1889#endif
1890	if (!delta) {
1891		err = -EINVAL;
1892		if (!pmc->sfcount[sfmode])
1893			goto out_unlock;
1894		pmc->sfcount[sfmode]--;
1895	}
1896	err = 0;
1897	for (i = 0; i < sfcount; i++) {
1898		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1899
1900		changerec |= rv > 0;
1901		if (!err && rv < 0)
1902			err = rv;
1903	}
1904	if (pmc->sfmode == MCAST_EXCLUDE &&
1905	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1906	    pmc->sfcount[MCAST_INCLUDE]) {
1907#ifdef CONFIG_IP_MULTICAST
1908		struct ip_sf_list *psf;
1909		struct net *net = dev_net(in_dev->dev);
1910#endif
1911
1912		/* filter mode change */
1913		pmc->sfmode = MCAST_INCLUDE;
1914#ifdef CONFIG_IP_MULTICAST
1915		pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1916		in_dev->mr_ifc_count = pmc->crcount;
1917		for (psf = pmc->sources; psf; psf = psf->sf_next)
1918			psf->sf_crcount = 0;
1919		igmp_ifc_event(pmc->interface);
1920	} else if (sf_setstate(pmc) || changerec) {
1921		igmp_ifc_event(pmc->interface);
1922#endif
1923	}
1924out_unlock:
1925	spin_unlock_bh(&pmc->lock);
1926	return err;
1927}
1928
1929/*
1930 * Add multicast single-source filter to the interface list
1931 */
1932static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1933	__be32 *psfsrc)
1934{
1935	struct ip_sf_list *psf, *psf_prev;
1936
1937	psf_prev = NULL;
1938	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1939		if (psf->sf_inaddr == *psfsrc)
1940			break;
1941		psf_prev = psf;
1942	}
1943	if (!psf) {
1944		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1945		if (!psf)
1946			return -ENOBUFS;
1947		psf->sf_inaddr = *psfsrc;
1948		if (psf_prev) {
1949			psf_prev->sf_next = psf;
1950		} else
1951			pmc->sources = psf;
1952	}
1953	psf->sf_count[sfmode]++;
1954	if (psf->sf_count[sfmode] == 1) {
1955		ip_rt_multicast_event(pmc->interface);
1956	}
1957	return 0;
1958}
1959
1960#ifdef CONFIG_IP_MULTICAST
1961static void sf_markstate(struct ip_mc_list *pmc)
1962{
1963	struct ip_sf_list *psf;
1964	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1965
1966	for (psf = pmc->sources; psf; psf = psf->sf_next)
1967		if (pmc->sfcount[MCAST_EXCLUDE]) {
1968			psf->sf_oldin = mca_xcount ==
1969				psf->sf_count[MCAST_EXCLUDE] &&
1970				!psf->sf_count[MCAST_INCLUDE];
1971		} else
1972			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1973}
1974
1975static int sf_setstate(struct ip_mc_list *pmc)
1976{
1977	struct ip_sf_list *psf, *dpsf;
1978	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1979	int qrv = pmc->interface->mr_qrv;
1980	int new_in, rv;
1981
1982	rv = 0;
1983	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1984		if (pmc->sfcount[MCAST_EXCLUDE]) {
1985			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1986				!psf->sf_count[MCAST_INCLUDE];
1987		} else
1988			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1989		if (new_in) {
1990			if (!psf->sf_oldin) {
1991				struct ip_sf_list *prev = NULL;
1992
1993				for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) {
1994					if (dpsf->sf_inaddr == psf->sf_inaddr)
1995						break;
1996					prev = dpsf;
1997				}
1998				if (dpsf) {
1999					if (prev)
2000						prev->sf_next = dpsf->sf_next;
2001					else
2002						pmc->tomb = dpsf->sf_next;
2003					kfree(dpsf);
2004				}
2005				psf->sf_crcount = qrv;
2006				rv++;
2007			}
2008		} else if (psf->sf_oldin) {
2009
2010			psf->sf_crcount = 0;
2011			/*
2012			 * add or update "delete" records if an active filter
2013			 * is now inactive
2014			 */
2015			for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next)
2016				if (dpsf->sf_inaddr == psf->sf_inaddr)
2017					break;
2018			if (!dpsf) {
2019				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
2020				if (!dpsf)
2021					continue;
2022				*dpsf = *psf;
2023				/* pmc->lock held by callers */
2024				dpsf->sf_next = pmc->tomb;
2025				pmc->tomb = dpsf;
2026			}
2027			dpsf->sf_crcount = qrv;
2028			rv++;
2029		}
2030	}
2031	return rv;
2032}
2033#endif
2034
2035/*
2036 * Add multicast source filter list to the interface list
2037 */
2038static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
2039			 int sfcount, __be32 *psfsrc, int delta)
2040{
2041	struct ip_mc_list *pmc;
2042	int	isexclude;
2043	int	i, err;
2044
2045	if (!in_dev)
2046		return -ENODEV;
2047	rcu_read_lock();
2048	for_each_pmc_rcu(in_dev, pmc) {
2049		if (*pmca == pmc->multiaddr)
2050			break;
2051	}
2052	if (!pmc) {
2053		/* MCA not found?? bug */
2054		rcu_read_unlock();
2055		return -ESRCH;
2056	}
2057	spin_lock_bh(&pmc->lock);
2058	rcu_read_unlock();
2059
2060#ifdef CONFIG_IP_MULTICAST
2061	sf_markstate(pmc);
2062#endif
2063	isexclude = pmc->sfmode == MCAST_EXCLUDE;
2064	if (!delta)
2065		pmc->sfcount[sfmode]++;
2066	err = 0;
2067	for (i = 0; i < sfcount; i++) {
2068		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2069		if (err)
2070			break;
2071	}
2072	if (err) {
2073		int j;
2074
2075		if (!delta)
2076			pmc->sfcount[sfmode]--;
2077		for (j = 0; j < i; j++)
2078			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2079	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
2080#ifdef CONFIG_IP_MULTICAST
2081		struct ip_sf_list *psf;
2082		struct net *net = dev_net(pmc->interface->dev);
2083		in_dev = pmc->interface;
2084#endif
2085
2086		/* filter mode change */
2087		if (pmc->sfcount[MCAST_EXCLUDE])
2088			pmc->sfmode = MCAST_EXCLUDE;
2089		else if (pmc->sfcount[MCAST_INCLUDE])
2090			pmc->sfmode = MCAST_INCLUDE;
2091#ifdef CONFIG_IP_MULTICAST
2092		/* else no filters; keep old mode for reports */
2093
2094		pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
2095		in_dev->mr_ifc_count = pmc->crcount;
2096		for (psf = pmc->sources; psf; psf = psf->sf_next)
2097			psf->sf_crcount = 0;
2098		igmp_ifc_event(in_dev);
2099	} else if (sf_setstate(pmc)) {
2100		igmp_ifc_event(in_dev);
2101#endif
2102	}
2103	spin_unlock_bh(&pmc->lock);
2104	return err;
2105}
2106
2107static void ip_mc_clear_src(struct ip_mc_list *pmc)
2108{
2109	struct ip_sf_list *psf, *nextpsf, *tomb, *sources;
2110
2111	spin_lock_bh(&pmc->lock);
2112	tomb = pmc->tomb;
2113	pmc->tomb = NULL;
2114	sources = pmc->sources;
2115	pmc->sources = NULL;
2116	pmc->sfmode = MCAST_EXCLUDE;
2117	pmc->sfcount[MCAST_INCLUDE] = 0;
2118	pmc->sfcount[MCAST_EXCLUDE] = 1;
2119	spin_unlock_bh(&pmc->lock);
2120
2121	for (psf = tomb; psf; psf = nextpsf) {
2122		nextpsf = psf->sf_next;
2123		kfree(psf);
2124	}
2125	for (psf = sources; psf; psf = nextpsf) {
2126		nextpsf = psf->sf_next;
2127		kfree(psf);
2128	}
2129}
2130
2131/* Join a multicast group
2132 */
2133
2134int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
2135{
2136	__be32 addr = imr->imr_multiaddr.s_addr;
2137	struct ip_mc_socklist *iml, *i;
2138	struct in_device *in_dev;
2139	struct inet_sock *inet = inet_sk(sk);
2140	struct net *net = sock_net(sk);
2141	int ifindex;
2142	int count = 0;
2143	int err;
2144
2145	ASSERT_RTNL();
2146
2147	if (!ipv4_is_multicast(addr))
2148		return -EINVAL;
2149
2150	in_dev = ip_mc_find_dev(net, imr);
2151
2152	if (!in_dev) {
2153		err = -ENODEV;
2154		goto done;
2155	}
2156
2157	err = -EADDRINUSE;
2158	ifindex = imr->imr_ifindex;
2159	for_each_pmc_rtnl(inet, i) {
2160		if (i->multi.imr_multiaddr.s_addr == addr &&
2161		    i->multi.imr_ifindex == ifindex)
2162			goto done;
2163		count++;
2164	}
2165	err = -ENOBUFS;
2166	if (count >= net->ipv4.sysctl_igmp_max_memberships)
2167		goto done;
2168	iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
2169	if (!iml)
2170		goto done;
2171
2172	memcpy(&iml->multi, imr, sizeof(*imr));
2173	iml->next_rcu = inet->mc_list;
2174	iml->sflist = NULL;
2175	iml->sfmode = MCAST_EXCLUDE;
2176	rcu_assign_pointer(inet->mc_list, iml);
2177	ip_mc_inc_group(in_dev, addr);
2178	err = 0;
2179done:
2180	return err;
2181}
 
 
 
 
 
 
 
2182EXPORT_SYMBOL(ip_mc_join_group);
2183
 
 
 
 
 
 
 
 
2184static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
2185			   struct in_device *in_dev)
2186{
2187	struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
2188	int err;
2189
2190	if (!psf) {
2191		/* any-source empty exclude case */
2192		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2193			iml->sfmode, 0, NULL, 0);
2194	}
2195	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2196			iml->sfmode, psf->sl_count, psf->sl_addr, 0);
2197	RCU_INIT_POINTER(iml->sflist, NULL);
2198	/* decrease mem now to avoid the memleak warning */
2199	atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc);
2200	kfree_rcu(psf, rcu);
2201	return err;
2202}
2203
2204int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
2205{
2206	struct inet_sock *inet = inet_sk(sk);
2207	struct ip_mc_socklist *iml;
2208	struct ip_mc_socklist __rcu **imlp;
2209	struct in_device *in_dev;
2210	struct net *net = sock_net(sk);
2211	__be32 group = imr->imr_multiaddr.s_addr;
2212	u32 ifindex;
2213	int ret = -EADDRNOTAVAIL;
2214
2215	ASSERT_RTNL();
2216
2217	in_dev = ip_mc_find_dev(net, imr);
2218	if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) {
2219		ret = -ENODEV;
2220		goto out;
2221	}
2222	ifindex = imr->imr_ifindex;
2223	for (imlp = &inet->mc_list;
2224	     (iml = rtnl_dereference(*imlp)) != NULL;
2225	     imlp = &iml->next_rcu) {
2226		if (iml->multi.imr_multiaddr.s_addr != group)
2227			continue;
2228		if (ifindex) {
2229			if (iml->multi.imr_ifindex != ifindex)
2230				continue;
2231		} else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
2232				iml->multi.imr_address.s_addr)
2233			continue;
2234
2235		(void) ip_mc_leave_src(sk, iml, in_dev);
2236
2237		*imlp = iml->next_rcu;
2238
2239		if (in_dev)
2240			ip_mc_dec_group(in_dev, group);
2241
2242		/* decrease mem now to avoid the memleak warning */
2243		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2244		kfree_rcu(iml, rcu);
2245		return 0;
2246	}
2247out:
2248	return ret;
2249}
2250EXPORT_SYMBOL(ip_mc_leave_group);
2251
2252int ip_mc_source(int add, int omode, struct sock *sk, struct
2253	ip_mreq_source *mreqs, int ifindex)
2254{
2255	int err;
2256	struct ip_mreqn imr;
2257	__be32 addr = mreqs->imr_multiaddr;
2258	struct ip_mc_socklist *pmc;
2259	struct in_device *in_dev = NULL;
2260	struct inet_sock *inet = inet_sk(sk);
2261	struct ip_sf_socklist *psl;
2262	struct net *net = sock_net(sk);
2263	int leavegroup = 0;
2264	int i, j, rv;
2265
2266	if (!ipv4_is_multicast(addr))
2267		return -EINVAL;
2268
2269	ASSERT_RTNL();
2270
2271	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
2272	imr.imr_address.s_addr = mreqs->imr_interface;
2273	imr.imr_ifindex = ifindex;
2274	in_dev = ip_mc_find_dev(net, &imr);
2275
2276	if (!in_dev) {
2277		err = -ENODEV;
2278		goto done;
2279	}
2280	err = -EADDRNOTAVAIL;
2281
2282	for_each_pmc_rtnl(inet, pmc) {
2283		if ((pmc->multi.imr_multiaddr.s_addr ==
2284		     imr.imr_multiaddr.s_addr) &&
2285		    (pmc->multi.imr_ifindex == imr.imr_ifindex))
2286			break;
2287	}
2288	if (!pmc) {		/* must have a prior join */
2289		err = -EINVAL;
2290		goto done;
2291	}
2292	/* if a source filter was set, must be the same mode as before */
2293	if (pmc->sflist) {
2294		if (pmc->sfmode != omode) {
2295			err = -EINVAL;
2296			goto done;
2297		}
2298	} else if (pmc->sfmode != omode) {
2299		/* allow mode switches for empty-set filters */
2300		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
2301		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
2302			NULL, 0);
2303		pmc->sfmode = omode;
2304	}
2305
2306	psl = rtnl_dereference(pmc->sflist);
2307	if (!add) {
2308		if (!psl)
2309			goto done;	/* err = -EADDRNOTAVAIL */
2310		rv = !0;
2311		for (i = 0; i < psl->sl_count; i++) {
2312			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2313				sizeof(__be32));
2314			if (rv == 0)
2315				break;
2316		}
2317		if (rv)		/* source not found */
2318			goto done;	/* err = -EADDRNOTAVAIL */
2319
2320		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2321		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
2322			leavegroup = 1;
2323			goto done;
2324		}
2325
2326		/* update the interface filter */
2327		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2328			&mreqs->imr_sourceaddr, 1);
2329
2330		for (j = i+1; j < psl->sl_count; j++)
2331			psl->sl_addr[j-1] = psl->sl_addr[j];
2332		psl->sl_count--;
2333		err = 0;
2334		goto done;
2335	}
2336	/* else, add a new source to the filter */
2337
2338	if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) {
2339		err = -ENOBUFS;
2340		goto done;
2341	}
2342	if (!psl || psl->sl_count == psl->sl_max) {
2343		struct ip_sf_socklist *newpsl;
2344		int count = IP_SFBLOCK;
2345
2346		if (psl)
2347			count += psl->sl_max;
2348		newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
2349		if (!newpsl) {
2350			err = -ENOBUFS;
2351			goto done;
2352		}
2353		newpsl->sl_max = count;
2354		newpsl->sl_count = count - IP_SFBLOCK;
2355		if (psl) {
2356			for (i = 0; i < psl->sl_count; i++)
2357				newpsl->sl_addr[i] = psl->sl_addr[i];
2358			/* decrease mem now to avoid the memleak warning */
2359			atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2360			kfree_rcu(psl, rcu);
2361		}
2362		rcu_assign_pointer(pmc->sflist, newpsl);
2363		psl = newpsl;
2364	}
2365	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
2366	for (i = 0; i < psl->sl_count; i++) {
2367		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2368			sizeof(__be32));
2369		if (rv == 0)
2370			break;
2371	}
2372	if (rv == 0)		/* address already there is an error */
2373		goto done;
2374	for (j = psl->sl_count-1; j >= i; j--)
2375		psl->sl_addr[j+1] = psl->sl_addr[j];
2376	psl->sl_addr[i] = mreqs->imr_sourceaddr;
2377	psl->sl_count++;
2378	err = 0;
2379	/* update the interface list */
2380	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2381		&mreqs->imr_sourceaddr, 1);
2382done:
2383	if (leavegroup)
2384		err = ip_mc_leave_group(sk, &imr);
2385	return err;
2386}
2387
2388int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2389{
2390	int err = 0;
2391	struct ip_mreqn	imr;
2392	__be32 addr = msf->imsf_multiaddr;
2393	struct ip_mc_socklist *pmc;
2394	struct in_device *in_dev;
2395	struct inet_sock *inet = inet_sk(sk);
2396	struct ip_sf_socklist *newpsl, *psl;
2397	struct net *net = sock_net(sk);
2398	int leavegroup = 0;
2399
2400	if (!ipv4_is_multicast(addr))
2401		return -EINVAL;
2402	if (msf->imsf_fmode != MCAST_INCLUDE &&
2403	    msf->imsf_fmode != MCAST_EXCLUDE)
2404		return -EINVAL;
2405
2406	ASSERT_RTNL();
2407
2408	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2409	imr.imr_address.s_addr = msf->imsf_interface;
2410	imr.imr_ifindex = ifindex;
2411	in_dev = ip_mc_find_dev(net, &imr);
2412
2413	if (!in_dev) {
2414		err = -ENODEV;
2415		goto done;
2416	}
2417
2418	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2419	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2420		leavegroup = 1;
2421		goto done;
2422	}
2423
2424	for_each_pmc_rtnl(inet, pmc) {
2425		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2426		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2427			break;
2428	}
2429	if (!pmc) {		/* must have a prior join */
2430		err = -EINVAL;
2431		goto done;
2432	}
2433	if (msf->imsf_numsrc) {
2434		newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2435							   GFP_KERNEL);
2436		if (!newpsl) {
2437			err = -ENOBUFS;
2438			goto done;
2439		}
2440		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2441		memcpy(newpsl->sl_addr, msf->imsf_slist,
2442			msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2443		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2444			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2445		if (err) {
2446			sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2447			goto done;
2448		}
2449	} else {
2450		newpsl = NULL;
2451		(void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2452				     msf->imsf_fmode, 0, NULL, 0);
2453	}
2454	psl = rtnl_dereference(pmc->sflist);
2455	if (psl) {
2456		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2457			psl->sl_count, psl->sl_addr, 0);
2458		/* decrease mem now to avoid the memleak warning */
2459		atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2460		kfree_rcu(psl, rcu);
2461	} else
2462		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2463			0, NULL, 0);
2464	rcu_assign_pointer(pmc->sflist, newpsl);
2465	pmc->sfmode = msf->imsf_fmode;
2466	err = 0;
2467done:
2468	if (leavegroup)
2469		err = ip_mc_leave_group(sk, &imr);
2470	return err;
2471}
2472
2473int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2474	struct ip_msfilter __user *optval, int __user *optlen)
2475{
2476	int err, len, count, copycount;
2477	struct ip_mreqn	imr;
2478	__be32 addr = msf->imsf_multiaddr;
2479	struct ip_mc_socklist *pmc;
2480	struct in_device *in_dev;
2481	struct inet_sock *inet = inet_sk(sk);
2482	struct ip_sf_socklist *psl;
2483	struct net *net = sock_net(sk);
2484
2485	ASSERT_RTNL();
2486
2487	if (!ipv4_is_multicast(addr))
2488		return -EINVAL;
2489
2490	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2491	imr.imr_address.s_addr = msf->imsf_interface;
2492	imr.imr_ifindex = 0;
2493	in_dev = ip_mc_find_dev(net, &imr);
2494
2495	if (!in_dev) {
2496		err = -ENODEV;
2497		goto done;
2498	}
2499	err = -EADDRNOTAVAIL;
2500
2501	for_each_pmc_rtnl(inet, pmc) {
2502		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2503		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2504			break;
2505	}
2506	if (!pmc)		/* must have a prior join */
2507		goto done;
2508	msf->imsf_fmode = pmc->sfmode;
2509	psl = rtnl_dereference(pmc->sflist);
2510	if (!psl) {
2511		len = 0;
2512		count = 0;
2513	} else {
2514		count = psl->sl_count;
2515	}
2516	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2517	len = copycount * sizeof(psl->sl_addr[0]);
2518	msf->imsf_numsrc = count;
2519	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2520	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2521		return -EFAULT;
2522	}
2523	if (len &&
2524	    copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2525		return -EFAULT;
2526	return 0;
2527done:
2528	return err;
2529}
2530
2531int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2532	struct group_filter __user *optval, int __user *optlen)
2533{
2534	int err, i, count, copycount;
2535	struct sockaddr_in *psin;
2536	__be32 addr;
2537	struct ip_mc_socklist *pmc;
2538	struct inet_sock *inet = inet_sk(sk);
2539	struct ip_sf_socklist *psl;
2540
2541	ASSERT_RTNL();
2542
2543	psin = (struct sockaddr_in *)&gsf->gf_group;
2544	if (psin->sin_family != AF_INET)
2545		return -EINVAL;
2546	addr = psin->sin_addr.s_addr;
2547	if (!ipv4_is_multicast(addr))
2548		return -EINVAL;
2549
2550	err = -EADDRNOTAVAIL;
2551
2552	for_each_pmc_rtnl(inet, pmc) {
2553		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2554		    pmc->multi.imr_ifindex == gsf->gf_interface)
2555			break;
2556	}
2557	if (!pmc)		/* must have a prior join */
2558		goto done;
2559	gsf->gf_fmode = pmc->sfmode;
2560	psl = rtnl_dereference(pmc->sflist);
2561	count = psl ? psl->sl_count : 0;
2562	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2563	gsf->gf_numsrc = count;
2564	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2565	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2566		return -EFAULT;
2567	}
2568	for (i = 0; i < copycount; i++) {
2569		struct sockaddr_storage ss;
2570
2571		psin = (struct sockaddr_in *)&ss;
2572		memset(&ss, 0, sizeof(ss));
2573		psin->sin_family = AF_INET;
2574		psin->sin_addr.s_addr = psl->sl_addr[i];
2575		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2576			return -EFAULT;
2577	}
2578	return 0;
2579done:
2580	return err;
2581}
2582
2583/*
2584 * check if a multicast source filter allows delivery for a given <src,dst,intf>
2585 */
2586int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr,
2587		   int dif, int sdif)
2588{
2589	struct inet_sock *inet = inet_sk(sk);
2590	struct ip_mc_socklist *pmc;
2591	struct ip_sf_socklist *psl;
2592	int i;
2593	int ret;
2594
2595	ret = 1;
2596	if (!ipv4_is_multicast(loc_addr))
2597		goto out;
2598
2599	rcu_read_lock();
2600	for_each_pmc_rcu(inet, pmc) {
2601		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2602		    (pmc->multi.imr_ifindex == dif ||
2603		     (sdif && pmc->multi.imr_ifindex == sdif)))
2604			break;
2605	}
2606	ret = inet->mc_all;
2607	if (!pmc)
2608		goto unlock;
2609	psl = rcu_dereference(pmc->sflist);
2610	ret = (pmc->sfmode == MCAST_EXCLUDE);
2611	if (!psl)
2612		goto unlock;
2613
2614	for (i = 0; i < psl->sl_count; i++) {
2615		if (psl->sl_addr[i] == rmt_addr)
2616			break;
2617	}
2618	ret = 0;
2619	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2620		goto unlock;
2621	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2622		goto unlock;
2623	ret = 1;
2624unlock:
2625	rcu_read_unlock();
2626out:
2627	return ret;
2628}
2629
2630/*
2631 *	A socket is closing.
2632 */
2633
2634void ip_mc_drop_socket(struct sock *sk)
2635{
2636	struct inet_sock *inet = inet_sk(sk);
2637	struct ip_mc_socklist *iml;
2638	struct net *net = sock_net(sk);
2639
2640	if (!inet->mc_list)
2641		return;
2642
2643	rtnl_lock();
2644	while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2645		struct in_device *in_dev;
2646
2647		inet->mc_list = iml->next_rcu;
2648		in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2649		(void) ip_mc_leave_src(sk, iml, in_dev);
2650		if (in_dev)
2651			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2652		/* decrease mem now to avoid the memleak warning */
2653		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2654		kfree_rcu(iml, rcu);
2655	}
2656	rtnl_unlock();
2657}
2658
2659/* called with rcu_read_lock() */
2660int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto)
2661{
2662	struct ip_mc_list *im;
2663	struct ip_mc_list __rcu **mc_hash;
2664	struct ip_sf_list *psf;
2665	int rv = 0;
2666
2667	mc_hash = rcu_dereference(in_dev->mc_hash);
2668	if (mc_hash) {
2669		u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
2670
2671		for (im = rcu_dereference(mc_hash[hash]);
2672		     im != NULL;
2673		     im = rcu_dereference(im->next_hash)) {
2674			if (im->multiaddr == mc_addr)
2675				break;
2676		}
2677	} else {
2678		for_each_pmc_rcu(in_dev, im) {
2679			if (im->multiaddr == mc_addr)
2680				break;
2681		}
2682	}
2683	if (im && proto == IPPROTO_IGMP) {
2684		rv = 1;
2685	} else if (im) {
2686		if (src_addr) {
 
2687			for (psf = im->sources; psf; psf = psf->sf_next) {
2688				if (psf->sf_inaddr == src_addr)
2689					break;
2690			}
2691			if (psf)
2692				rv = psf->sf_count[MCAST_INCLUDE] ||
2693					psf->sf_count[MCAST_EXCLUDE] !=
2694					im->sfcount[MCAST_EXCLUDE];
2695			else
2696				rv = im->sfcount[MCAST_EXCLUDE] != 0;
 
2697		} else
2698			rv = 1; /* unspecified source; tentatively allow */
2699	}
2700	return rv;
2701}
2702
2703#if defined(CONFIG_PROC_FS)
2704struct igmp_mc_iter_state {
2705	struct seq_net_private p;
2706	struct net_device *dev;
2707	struct in_device *in_dev;
2708};
2709
2710#define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2711
2712static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2713{
2714	struct net *net = seq_file_net(seq);
2715	struct ip_mc_list *im = NULL;
2716	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2717
2718	state->in_dev = NULL;
2719	for_each_netdev_rcu(net, state->dev) {
2720		struct in_device *in_dev;
2721
2722		in_dev = __in_dev_get_rcu(state->dev);
2723		if (!in_dev)
2724			continue;
2725		im = rcu_dereference(in_dev->mc_list);
2726		if (im) {
2727			state->in_dev = in_dev;
2728			break;
2729		}
2730	}
2731	return im;
2732}
2733
2734static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2735{
2736	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2737
2738	im = rcu_dereference(im->next_rcu);
2739	while (!im) {
2740		state->dev = next_net_device_rcu(state->dev);
2741		if (!state->dev) {
2742			state->in_dev = NULL;
2743			break;
2744		}
2745		state->in_dev = __in_dev_get_rcu(state->dev);
2746		if (!state->in_dev)
2747			continue;
2748		im = rcu_dereference(state->in_dev->mc_list);
2749	}
2750	return im;
2751}
2752
2753static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2754{
2755	struct ip_mc_list *im = igmp_mc_get_first(seq);
2756	if (im)
2757		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2758			--pos;
2759	return pos ? NULL : im;
2760}
2761
2762static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2763	__acquires(rcu)
2764{
2765	rcu_read_lock();
2766	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2767}
2768
2769static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2770{
2771	struct ip_mc_list *im;
2772	if (v == SEQ_START_TOKEN)
2773		im = igmp_mc_get_first(seq);
2774	else
2775		im = igmp_mc_get_next(seq, v);
2776	++*pos;
2777	return im;
2778}
2779
2780static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2781	__releases(rcu)
2782{
2783	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2784
2785	state->in_dev = NULL;
2786	state->dev = NULL;
2787	rcu_read_unlock();
2788}
2789
2790static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2791{
2792	if (v == SEQ_START_TOKEN)
2793		seq_puts(seq,
2794			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2795	else {
2796		struct ip_mc_list *im = (struct ip_mc_list *)v;
2797		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2798		char   *querier;
2799		long delta;
2800
2801#ifdef CONFIG_IP_MULTICAST
2802		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2803			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2804			  "V3";
2805#else
2806		querier = "NONE";
2807#endif
2808
2809		if (rcu_access_pointer(state->in_dev->mc_list) == im) {
2810			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2811				   state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2812		}
2813
2814		delta = im->timer.expires - jiffies;
2815		seq_printf(seq,
2816			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2817			   im->multiaddr, im->users,
2818			   im->tm_running,
2819			   im->tm_running ? jiffies_delta_to_clock_t(delta) : 0,
2820			   im->reporter);
2821	}
2822	return 0;
2823}
2824
2825static const struct seq_operations igmp_mc_seq_ops = {
2826	.start	=	igmp_mc_seq_start,
2827	.next	=	igmp_mc_seq_next,
2828	.stop	=	igmp_mc_seq_stop,
2829	.show	=	igmp_mc_seq_show,
2830};
2831
2832static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2833{
2834	return seq_open_net(inode, file, &igmp_mc_seq_ops,
2835			sizeof(struct igmp_mc_iter_state));
2836}
2837
2838static const struct file_operations igmp_mc_seq_fops = {
2839	.open		=	igmp_mc_seq_open,
2840	.read		=	seq_read,
2841	.llseek		=	seq_lseek,
2842	.release	=	seq_release_net,
2843};
2844
2845struct igmp_mcf_iter_state {
2846	struct seq_net_private p;
2847	struct net_device *dev;
2848	struct in_device *idev;
2849	struct ip_mc_list *im;
2850};
2851
2852#define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2853
2854static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2855{
2856	struct net *net = seq_file_net(seq);
2857	struct ip_sf_list *psf = NULL;
2858	struct ip_mc_list *im = NULL;
2859	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2860
2861	state->idev = NULL;
2862	state->im = NULL;
2863	for_each_netdev_rcu(net, state->dev) {
2864		struct in_device *idev;
2865		idev = __in_dev_get_rcu(state->dev);
2866		if (unlikely(!idev))
2867			continue;
2868		im = rcu_dereference(idev->mc_list);
2869		if (likely(im)) {
2870			spin_lock_bh(&im->lock);
2871			psf = im->sources;
2872			if (likely(psf)) {
2873				state->im = im;
2874				state->idev = idev;
2875				break;
2876			}
2877			spin_unlock_bh(&im->lock);
2878		}
2879	}
2880	return psf;
2881}
2882
2883static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2884{
2885	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2886
2887	psf = psf->sf_next;
2888	while (!psf) {
2889		spin_unlock_bh(&state->im->lock);
2890		state->im = state->im->next;
2891		while (!state->im) {
2892			state->dev = next_net_device_rcu(state->dev);
2893			if (!state->dev) {
2894				state->idev = NULL;
2895				goto out;
2896			}
2897			state->idev = __in_dev_get_rcu(state->dev);
2898			if (!state->idev)
2899				continue;
2900			state->im = rcu_dereference(state->idev->mc_list);
2901		}
2902		if (!state->im)
2903			break;
2904		spin_lock_bh(&state->im->lock);
2905		psf = state->im->sources;
2906	}
2907out:
2908	return psf;
2909}
2910
2911static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2912{
2913	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2914	if (psf)
2915		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2916			--pos;
2917	return pos ? NULL : psf;
2918}
2919
2920static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2921	__acquires(rcu)
2922{
2923	rcu_read_lock();
2924	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2925}
2926
2927static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2928{
2929	struct ip_sf_list *psf;
2930	if (v == SEQ_START_TOKEN)
2931		psf = igmp_mcf_get_first(seq);
2932	else
2933		psf = igmp_mcf_get_next(seq, v);
2934	++*pos;
2935	return psf;
2936}
2937
2938static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2939	__releases(rcu)
2940{
2941	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2942	if (likely(state->im)) {
2943		spin_unlock_bh(&state->im->lock);
2944		state->im = NULL;
2945	}
2946	state->idev = NULL;
2947	state->dev = NULL;
2948	rcu_read_unlock();
2949}
2950
2951static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2952{
2953	struct ip_sf_list *psf = (struct ip_sf_list *)v;
2954	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2955
2956	if (v == SEQ_START_TOKEN) {
2957		seq_puts(seq, "Idx Device        MCA        SRC    INC    EXC\n");
2958	} else {
2959		seq_printf(seq,
2960			   "%3d %6.6s 0x%08x "
2961			   "0x%08x %6lu %6lu\n",
2962			   state->dev->ifindex, state->dev->name,
2963			   ntohl(state->im->multiaddr),
2964			   ntohl(psf->sf_inaddr),
2965			   psf->sf_count[MCAST_INCLUDE],
2966			   psf->sf_count[MCAST_EXCLUDE]);
2967	}
2968	return 0;
2969}
2970
2971static const struct seq_operations igmp_mcf_seq_ops = {
2972	.start	=	igmp_mcf_seq_start,
2973	.next	=	igmp_mcf_seq_next,
2974	.stop	=	igmp_mcf_seq_stop,
2975	.show	=	igmp_mcf_seq_show,
2976};
2977
2978static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2979{
2980	return seq_open_net(inode, file, &igmp_mcf_seq_ops,
2981			sizeof(struct igmp_mcf_iter_state));
2982}
2983
2984static const struct file_operations igmp_mcf_seq_fops = {
2985	.open		=	igmp_mcf_seq_open,
2986	.read		=	seq_read,
2987	.llseek		=	seq_lseek,
2988	.release	=	seq_release_net,
2989};
2990
2991static int __net_init igmp_net_init(struct net *net)
2992{
2993	struct proc_dir_entry *pde;
2994	int err;
2995
2996	pde = proc_create("igmp", 0444, net->proc_net, &igmp_mc_seq_fops);
 
2997	if (!pde)
2998		goto out_igmp;
2999	pde = proc_create("mcfilter", 0444, net->proc_net,
3000			  &igmp_mcf_seq_fops);
3001	if (!pde)
3002		goto out_mcfilter;
3003	err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET,
3004				   SOCK_DGRAM, 0, net);
3005	if (err < 0) {
3006		pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n",
3007		       err);
3008		goto out_sock;
3009	}
3010
3011	return 0;
3012
3013out_sock:
3014	remove_proc_entry("mcfilter", net->proc_net);
3015out_mcfilter:
3016	remove_proc_entry("igmp", net->proc_net);
3017out_igmp:
3018	return -ENOMEM;
3019}
3020
3021static void __net_exit igmp_net_exit(struct net *net)
3022{
3023	remove_proc_entry("mcfilter", net->proc_net);
3024	remove_proc_entry("igmp", net->proc_net);
3025	inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk);
3026}
3027
3028static struct pernet_operations igmp_net_ops = {
3029	.init = igmp_net_init,
3030	.exit = igmp_net_exit,
3031};
3032#endif
3033
3034static int igmp_netdev_event(struct notifier_block *this,
3035			     unsigned long event, void *ptr)
3036{
3037	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3038	struct in_device *in_dev;
3039
3040	switch (event) {
3041	case NETDEV_RESEND_IGMP:
3042		in_dev = __in_dev_get_rtnl(dev);
3043		if (in_dev)
3044			ip_mc_rejoin_groups(in_dev);
3045		break;
3046	default:
3047		break;
3048	}
3049	return NOTIFY_DONE;
3050}
3051
3052static struct notifier_block igmp_notifier = {
3053	.notifier_call = igmp_netdev_event,
3054};
3055
3056int __init igmp_mc_init(void)
3057{
3058#if defined(CONFIG_PROC_FS)
3059	int err;
3060
3061	err = register_pernet_subsys(&igmp_net_ops);
3062	if (err)
3063		return err;
3064	err = register_netdevice_notifier(&igmp_notifier);
3065	if (err)
3066		goto reg_notif_fail;
3067	return 0;
3068
3069reg_notif_fail:
3070	unregister_pernet_subsys(&igmp_net_ops);
3071	return err;
3072#else
3073	return register_netdevice_notifier(&igmp_notifier);
3074#endif
3075}