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v6.13.7
   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_RO(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_RO(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 = get_random_u32_below(max_delay);
 217
 218	im->tm_running = 1;
 219	if (refcount_inc_not_zero(&im->refcnt)) {
 220		if (mod_timer(&im->timer, jiffies + tv + 2))
 221			ip_ma_put(im);
 222	}
 223}
 224
 225static void igmp_gq_start_timer(struct in_device *in_dev)
 226{
 227	int tv = get_random_u32_below(in_dev->mr_maxdelay);
 228	unsigned long exp = jiffies + tv + 2;
 229
 230	if (in_dev->mr_gq_running &&
 231	    time_after_eq(exp, (in_dev->mr_gq_timer).expires))
 232		return;
 233
 234	in_dev->mr_gq_running = 1;
 235	if (!mod_timer(&in_dev->mr_gq_timer, exp))
 236		in_dev_hold(in_dev);
 237}
 238
 239static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
 240{
 241	int tv = get_random_u32_below(delay);
 242
 243	if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
 244		in_dev_hold(in_dev);
 245}
 246
 247static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
 248{
 249	spin_lock_bh(&im->lock);
 250	im->unsolicit_count = 0;
 251	if (del_timer(&im->timer)) {
 252		if ((long)(im->timer.expires-jiffies) < max_delay) {
 253			add_timer(&im->timer);
 254			im->tm_running = 1;
 255			spin_unlock_bh(&im->lock);
 256			return;
 257		}
 258		refcount_dec(&im->refcnt);
 259	}
 260	igmp_start_timer(im, max_delay);
 261	spin_unlock_bh(&im->lock);
 262}
 263
 264
 265/*
 266 *	Send an IGMP report.
 267 */
 268
 269#define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
 270
 271
 272static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
 273	int gdeleted, int sdeleted)
 274{
 275	switch (type) {
 276	case IGMPV3_MODE_IS_INCLUDE:
 277	case IGMPV3_MODE_IS_EXCLUDE:
 278		if (gdeleted || sdeleted)
 279			return 0;
 280		if (!(pmc->gsquery && !psf->sf_gsresp)) {
 281			if (pmc->sfmode == MCAST_INCLUDE)
 282				return 1;
 283			/* don't include if this source is excluded
 284			 * in all filters
 285			 */
 286			if (psf->sf_count[MCAST_INCLUDE])
 287				return type == IGMPV3_MODE_IS_INCLUDE;
 288			return pmc->sfcount[MCAST_EXCLUDE] ==
 289				psf->sf_count[MCAST_EXCLUDE];
 290		}
 291		return 0;
 292	case IGMPV3_CHANGE_TO_INCLUDE:
 293		if (gdeleted || sdeleted)
 294			return 0;
 295		return psf->sf_count[MCAST_INCLUDE] != 0;
 296	case IGMPV3_CHANGE_TO_EXCLUDE:
 297		if (gdeleted || sdeleted)
 298			return 0;
 299		if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
 300		    psf->sf_count[MCAST_INCLUDE])
 301			return 0;
 302		return pmc->sfcount[MCAST_EXCLUDE] ==
 303			psf->sf_count[MCAST_EXCLUDE];
 304	case IGMPV3_ALLOW_NEW_SOURCES:
 305		if (gdeleted || !psf->sf_crcount)
 306			return 0;
 307		return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
 308	case IGMPV3_BLOCK_OLD_SOURCES:
 309		if (pmc->sfmode == MCAST_INCLUDE)
 310			return gdeleted || (psf->sf_crcount && sdeleted);
 311		return psf->sf_crcount && !gdeleted && !sdeleted;
 312	}
 313	return 0;
 314}
 315
 316static int
 317igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
 318{
 319	struct ip_sf_list *psf;
 320	int scount = 0;
 321
 322	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 323		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
 324			continue;
 325		scount++;
 326	}
 327	return scount;
 328}
 329
 330/* source address selection per RFC 3376 section 4.2.13 */
 331static __be32 igmpv3_get_srcaddr(struct net_device *dev,
 332				 const struct flowi4 *fl4)
 333{
 334	struct in_device *in_dev = __in_dev_get_rcu(dev);
 335	const struct in_ifaddr *ifa;
 336
 337	if (!in_dev)
 338		return htonl(INADDR_ANY);
 339
 340	in_dev_for_each_ifa_rcu(ifa, in_dev) {
 341		if (fl4->saddr == ifa->ifa_local)
 342			return fl4->saddr;
 343	}
 344
 345	return htonl(INADDR_ANY);
 346}
 347
 348static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
 349{
 350	struct sk_buff *skb;
 351	struct rtable *rt;
 352	struct iphdr *pip;
 353	struct igmpv3_report *pig;
 354	struct net *net = dev_net(dev);
 355	struct flowi4 fl4;
 356	int hlen = LL_RESERVED_SPACE(dev);
 357	int tlen = dev->needed_tailroom;
 358	unsigned int size;
 359
 360	size = min(mtu, IP_MAX_MTU);
 361	while (1) {
 362		skb = alloc_skb(size + hlen + tlen,
 363				GFP_ATOMIC | __GFP_NOWARN);
 364		if (skb)
 365			break;
 366		size >>= 1;
 367		if (size < 256)
 368			return NULL;
 369	}
 370	skb->priority = TC_PRIO_CONTROL;
 371
 372	rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0,
 373				   0, 0,
 374				   IPPROTO_IGMP, 0, dev->ifindex);
 375	if (IS_ERR(rt)) {
 376		kfree_skb(skb);
 377		return NULL;
 378	}
 379
 380	skb_dst_set(skb, &rt->dst);
 381	skb->dev = dev;
 382
 383	skb_reserve(skb, hlen);
 384	skb_tailroom_reserve(skb, mtu, tlen);
 385
 386	skb_reset_network_header(skb);
 387	pip = ip_hdr(skb);
 388	skb_put(skb, sizeof(struct iphdr) + 4);
 389
 390	pip->version  = 4;
 391	pip->ihl      = (sizeof(struct iphdr)+4)>>2;
 392	pip->tos      = 0xc0;
 393	pip->frag_off = htons(IP_DF);
 394	pip->ttl      = 1;
 395	pip->daddr    = fl4.daddr;
 396
 397	rcu_read_lock();
 398	pip->saddr    = igmpv3_get_srcaddr(dev, &fl4);
 399	rcu_read_unlock();
 400
 401	pip->protocol = IPPROTO_IGMP;
 402	pip->tot_len  = 0;	/* filled in later */
 403	ip_select_ident(net, skb, NULL);
 404	((u8 *)&pip[1])[0] = IPOPT_RA;
 405	((u8 *)&pip[1])[1] = 4;
 406	((u8 *)&pip[1])[2] = 0;
 407	((u8 *)&pip[1])[3] = 0;
 408
 409	skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
 410	skb_put(skb, sizeof(*pig));
 411	pig = igmpv3_report_hdr(skb);
 412	pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
 413	pig->resv1 = 0;
 414	pig->csum = 0;
 415	pig->resv2 = 0;
 416	pig->ngrec = 0;
 417	return skb;
 418}
 419
 420static int igmpv3_sendpack(struct sk_buff *skb)
 421{
 422	struct igmphdr *pig = igmp_hdr(skb);
 423	const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
 424
 425	pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
 426
 427	return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
 428}
 429
 430static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
 431{
 432	return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
 433}
 434
 435static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
 436	int type, struct igmpv3_grec **ppgr, unsigned int mtu)
 437{
 438	struct net_device *dev = pmc->interface->dev;
 439	struct igmpv3_report *pih;
 440	struct igmpv3_grec *pgr;
 441
 442	if (!skb) {
 443		skb = igmpv3_newpack(dev, mtu);
 444		if (!skb)
 445			return NULL;
 446	}
 447	pgr = skb_put(skb, sizeof(struct igmpv3_grec));
 448	pgr->grec_type = type;
 449	pgr->grec_auxwords = 0;
 450	pgr->grec_nsrcs = 0;
 451	pgr->grec_mca = pmc->multiaddr;
 452	pih = igmpv3_report_hdr(skb);
 453	pih->ngrec = htons(ntohs(pih->ngrec)+1);
 454	*ppgr = pgr;
 455	return skb;
 456}
 457
 458#define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
 459
 460static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
 461	int type, int gdeleted, int sdeleted)
 462{
 463	struct net_device *dev = pmc->interface->dev;
 464	struct net *net = dev_net(dev);
 465	struct igmpv3_report *pih;
 466	struct igmpv3_grec *pgr = NULL;
 467	struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
 468	int scount, stotal, first, isquery, truncate;
 469	unsigned int mtu;
 470
 471	if (pmc->multiaddr == IGMP_ALL_HOSTS)
 472		return skb;
 473	if (ipv4_is_local_multicast(pmc->multiaddr) &&
 474	    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
 475		return skb;
 476
 477	mtu = READ_ONCE(dev->mtu);
 478	if (mtu < IPV4_MIN_MTU)
 479		return skb;
 480
 481	isquery = type == IGMPV3_MODE_IS_INCLUDE ||
 482		  type == IGMPV3_MODE_IS_EXCLUDE;
 483	truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
 484		    type == IGMPV3_CHANGE_TO_EXCLUDE;
 485
 486	stotal = scount = 0;
 487
 488	psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
 489
 490	if (!*psf_list)
 491		goto empty_source;
 492
 493	pih = skb ? igmpv3_report_hdr(skb) : NULL;
 494
 495	/* EX and TO_EX get a fresh packet, if needed */
 496	if (truncate) {
 497		if (pih && pih->ngrec &&
 498		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
 499			if (skb)
 500				igmpv3_sendpack(skb);
 501			skb = igmpv3_newpack(dev, mtu);
 502		}
 503	}
 504	first = 1;
 505	psf_prev = NULL;
 506	for (psf = *psf_list; psf; psf = psf_next) {
 507		__be32 *psrc;
 508
 509		psf_next = psf->sf_next;
 510
 511		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
 512			psf_prev = psf;
 513			continue;
 514		}
 515
 516		/* Based on RFC3376 5.1. Should not send source-list change
 517		 * records when there is a filter mode change.
 518		 */
 519		if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) ||
 520		     (!gdeleted && pmc->crcount)) &&
 521		    (type == IGMPV3_ALLOW_NEW_SOURCES ||
 522		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount)
 523			goto decrease_sf_crcount;
 524
 525		/* clear marks on query responses */
 526		if (isquery)
 527			psf->sf_gsresp = 0;
 528
 529		if (AVAILABLE(skb) < sizeof(__be32) +
 530		    first*sizeof(struct igmpv3_grec)) {
 531			if (truncate && !first)
 532				break;	 /* truncate these */
 533			if (pgr)
 534				pgr->grec_nsrcs = htons(scount);
 535			if (skb)
 536				igmpv3_sendpack(skb);
 537			skb = igmpv3_newpack(dev, mtu);
 538			first = 1;
 539			scount = 0;
 540		}
 541		if (first) {
 542			skb = add_grhead(skb, pmc, type, &pgr, mtu);
 543			first = 0;
 544		}
 545		if (!skb)
 546			return NULL;
 547		psrc = skb_put(skb, sizeof(__be32));
 548		*psrc = psf->sf_inaddr;
 549		scount++; stotal++;
 550		if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
 551		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
 552decrease_sf_crcount:
 553			psf->sf_crcount--;
 554			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
 555				if (psf_prev)
 556					psf_prev->sf_next = psf->sf_next;
 557				else
 558					*psf_list = psf->sf_next;
 559				kfree(psf);
 560				continue;
 561			}
 562		}
 563		psf_prev = psf;
 564	}
 565
 566empty_source:
 567	if (!stotal) {
 568		if (type == IGMPV3_ALLOW_NEW_SOURCES ||
 569		    type == IGMPV3_BLOCK_OLD_SOURCES)
 570			return skb;
 571		if (pmc->crcount || isquery) {
 572			/* make sure we have room for group header */
 573			if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) {
 574				igmpv3_sendpack(skb);
 575				skb = NULL; /* add_grhead will get a new one */
 576			}
 577			skb = add_grhead(skb, pmc, type, &pgr, mtu);
 578		}
 579	}
 580	if (pgr)
 581		pgr->grec_nsrcs = htons(scount);
 582
 583	if (isquery)
 584		pmc->gsquery = 0;	/* clear query state on report */
 585	return skb;
 586}
 587
 588static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
 589{
 590	struct sk_buff *skb = NULL;
 591	struct net *net = dev_net(in_dev->dev);
 592	int type;
 593
 594	if (!pmc) {
 595		rcu_read_lock();
 596		for_each_pmc_rcu(in_dev, pmc) {
 597			if (pmc->multiaddr == IGMP_ALL_HOSTS)
 598				continue;
 599			if (ipv4_is_local_multicast(pmc->multiaddr) &&
 600			    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
 601				continue;
 602			spin_lock_bh(&pmc->lock);
 603			if (pmc->sfcount[MCAST_EXCLUDE])
 604				type = IGMPV3_MODE_IS_EXCLUDE;
 605			else
 606				type = IGMPV3_MODE_IS_INCLUDE;
 607			skb = add_grec(skb, pmc, type, 0, 0);
 608			spin_unlock_bh(&pmc->lock);
 609		}
 610		rcu_read_unlock();
 611	} else {
 612		spin_lock_bh(&pmc->lock);
 613		if (pmc->sfcount[MCAST_EXCLUDE])
 614			type = IGMPV3_MODE_IS_EXCLUDE;
 615		else
 616			type = IGMPV3_MODE_IS_INCLUDE;
 617		skb = add_grec(skb, pmc, type, 0, 0);
 618		spin_unlock_bh(&pmc->lock);
 619	}
 620	if (!skb)
 621		return 0;
 622	return igmpv3_sendpack(skb);
 623}
 624
 625/*
 626 * remove zero-count source records from a source filter list
 627 */
 628static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
 629{
 630	struct ip_sf_list *psf_prev, *psf_next, *psf;
 631
 632	psf_prev = NULL;
 633	for (psf = *ppsf; psf; psf = psf_next) {
 634		psf_next = psf->sf_next;
 635		if (psf->sf_crcount == 0) {
 636			if (psf_prev)
 637				psf_prev->sf_next = psf->sf_next;
 638			else
 639				*ppsf = psf->sf_next;
 640			kfree(psf);
 641		} else
 642			psf_prev = psf;
 643	}
 644}
 645
 646static void kfree_pmc(struct ip_mc_list *pmc)
 647{
 648	ip_sf_list_clear_all(pmc->sources);
 649	ip_sf_list_clear_all(pmc->tomb);
 650	kfree(pmc);
 651}
 652
 653static void igmpv3_send_cr(struct in_device *in_dev)
 654{
 655	struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
 656	struct sk_buff *skb = NULL;
 657	int type, dtype;
 658
 659	rcu_read_lock();
 660	spin_lock_bh(&in_dev->mc_tomb_lock);
 661
 662	/* deleted MCA's */
 663	pmc_prev = NULL;
 664	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) {
 665		pmc_next = pmc->next;
 666		if (pmc->sfmode == MCAST_INCLUDE) {
 667			type = IGMPV3_BLOCK_OLD_SOURCES;
 668			dtype = IGMPV3_BLOCK_OLD_SOURCES;
 669			skb = add_grec(skb, pmc, type, 1, 0);
 670			skb = add_grec(skb, pmc, dtype, 1, 1);
 671		}
 672		if (pmc->crcount) {
 673			if (pmc->sfmode == MCAST_EXCLUDE) {
 674				type = IGMPV3_CHANGE_TO_INCLUDE;
 675				skb = add_grec(skb, pmc, type, 1, 0);
 676			}
 677			pmc->crcount--;
 678			if (pmc->crcount == 0) {
 679				igmpv3_clear_zeros(&pmc->tomb);
 680				igmpv3_clear_zeros(&pmc->sources);
 681			}
 682		}
 683		if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
 684			if (pmc_prev)
 685				pmc_prev->next = pmc_next;
 686			else
 687				in_dev->mc_tomb = pmc_next;
 688			in_dev_put(pmc->interface);
 689			kfree_pmc(pmc);
 690		} else
 691			pmc_prev = pmc;
 692	}
 693	spin_unlock_bh(&in_dev->mc_tomb_lock);
 694
 695	/* change recs */
 696	for_each_pmc_rcu(in_dev, pmc) {
 697		spin_lock_bh(&pmc->lock);
 698		if (pmc->sfcount[MCAST_EXCLUDE]) {
 699			type = IGMPV3_BLOCK_OLD_SOURCES;
 700			dtype = IGMPV3_ALLOW_NEW_SOURCES;
 701		} else {
 702			type = IGMPV3_ALLOW_NEW_SOURCES;
 703			dtype = IGMPV3_BLOCK_OLD_SOURCES;
 704		}
 705		skb = add_grec(skb, pmc, type, 0, 0);
 706		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
 707
 708		/* filter mode changes */
 709		if (pmc->crcount) {
 710			if (pmc->sfmode == MCAST_EXCLUDE)
 711				type = IGMPV3_CHANGE_TO_EXCLUDE;
 712			else
 713				type = IGMPV3_CHANGE_TO_INCLUDE;
 714			skb = add_grec(skb, pmc, type, 0, 0);
 715			pmc->crcount--;
 716		}
 717		spin_unlock_bh(&pmc->lock);
 718	}
 719	rcu_read_unlock();
 720
 721	if (!skb)
 722		return;
 723	(void) igmpv3_sendpack(skb);
 724}
 725
 726static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
 727	int type)
 728{
 729	struct sk_buff *skb;
 730	struct iphdr *iph;
 731	struct igmphdr *ih;
 732	struct rtable *rt;
 733	struct net_device *dev = in_dev->dev;
 734	struct net *net = dev_net(dev);
 735	__be32	group = pmc ? pmc->multiaddr : 0;
 736	struct flowi4 fl4;
 737	__be32	dst;
 738	int hlen, tlen;
 739
 740	if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
 741		return igmpv3_send_report(in_dev, pmc);
 742
 743	if (ipv4_is_local_multicast(group) &&
 744	    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
 745		return 0;
 746
 747	if (type == IGMP_HOST_LEAVE_MESSAGE)
 748		dst = IGMP_ALL_ROUTER;
 749	else
 750		dst = group;
 751
 752	rt = ip_route_output_ports(net, &fl4, NULL, dst, 0,
 753				   0, 0,
 754				   IPPROTO_IGMP, 0, dev->ifindex);
 755	if (IS_ERR(rt))
 756		return -1;
 757
 758	hlen = LL_RESERVED_SPACE(dev);
 759	tlen = dev->needed_tailroom;
 760	skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC);
 761	if (!skb) {
 762		ip_rt_put(rt);
 763		return -1;
 764	}
 765	skb->priority = TC_PRIO_CONTROL;
 766
 767	skb_dst_set(skb, &rt->dst);
 768
 769	skb_reserve(skb, hlen);
 770
 771	skb_reset_network_header(skb);
 772	iph = ip_hdr(skb);
 773	skb_put(skb, sizeof(struct iphdr) + 4);
 774
 775	iph->version  = 4;
 776	iph->ihl      = (sizeof(struct iphdr)+4)>>2;
 777	iph->tos      = 0xc0;
 778	iph->frag_off = htons(IP_DF);
 779	iph->ttl      = 1;
 780	iph->daddr    = dst;
 781	iph->saddr    = fl4.saddr;
 782	iph->protocol = IPPROTO_IGMP;
 783	ip_select_ident(net, skb, NULL);
 784	((u8 *)&iph[1])[0] = IPOPT_RA;
 785	((u8 *)&iph[1])[1] = 4;
 786	((u8 *)&iph[1])[2] = 0;
 787	((u8 *)&iph[1])[3] = 0;
 788
 789	ih = skb_put(skb, sizeof(struct igmphdr));
 790	ih->type = type;
 791	ih->code = 0;
 792	ih->csum = 0;
 793	ih->group = group;
 794	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 795
 796	return ip_local_out(net, skb->sk, skb);
 797}
 798
 799static void igmp_gq_timer_expire(struct timer_list *t)
 800{
 801	struct in_device *in_dev = from_timer(in_dev, t, mr_gq_timer);
 802
 803	in_dev->mr_gq_running = 0;
 804	igmpv3_send_report(in_dev, NULL);
 805	in_dev_put(in_dev);
 806}
 807
 808static void igmp_ifc_timer_expire(struct timer_list *t)
 809{
 810	struct in_device *in_dev = from_timer(in_dev, t, mr_ifc_timer);
 811	u32 mr_ifc_count;
 812
 813	igmpv3_send_cr(in_dev);
 814restart:
 815	mr_ifc_count = READ_ONCE(in_dev->mr_ifc_count);
 816
 817	if (mr_ifc_count) {
 818		if (cmpxchg(&in_dev->mr_ifc_count,
 819			    mr_ifc_count,
 820			    mr_ifc_count - 1) != mr_ifc_count)
 821			goto restart;
 822		igmp_ifc_start_timer(in_dev,
 823				     unsolicited_report_interval(in_dev));
 824	}
 825	in_dev_put(in_dev);
 826}
 827
 828static void igmp_ifc_event(struct in_device *in_dev)
 829{
 830	struct net *net = dev_net(in_dev->dev);
 831	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 832		return;
 833	WRITE_ONCE(in_dev->mr_ifc_count, in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv));
 834	igmp_ifc_start_timer(in_dev, 1);
 835}
 836
 837
 838static void igmp_timer_expire(struct timer_list *t)
 839{
 840	struct ip_mc_list *im = from_timer(im, t, timer);
 841	struct in_device *in_dev = im->interface;
 842
 843	spin_lock(&im->lock);
 844	im->tm_running = 0;
 845
 846	if (im->unsolicit_count && --im->unsolicit_count)
 
 847		igmp_start_timer(im, unsolicited_report_interval(in_dev));
 848
 849	im->reporter = 1;
 850	spin_unlock(&im->lock);
 851
 852	if (IGMP_V1_SEEN(in_dev))
 853		igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
 854	else if (IGMP_V2_SEEN(in_dev))
 855		igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
 856	else
 857		igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
 858
 859	ip_ma_put(im);
 860}
 861
 862/* mark EXCLUDE-mode sources */
 863static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 864{
 865	struct ip_sf_list *psf;
 866	int i, scount;
 867
 868	scount = 0;
 869	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 870		if (scount == nsrcs)
 871			break;
 872		for (i = 0; i < nsrcs; i++) {
 873			/* skip inactive filters */
 874			if (psf->sf_count[MCAST_INCLUDE] ||
 875			    pmc->sfcount[MCAST_EXCLUDE] !=
 876			    psf->sf_count[MCAST_EXCLUDE])
 877				break;
 878			if (srcs[i] == psf->sf_inaddr) {
 879				scount++;
 880				break;
 881			}
 882		}
 883	}
 884	pmc->gsquery = 0;
 885	if (scount == nsrcs)	/* all sources excluded */
 886		return 0;
 887	return 1;
 888}
 889
 890static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 891{
 892	struct ip_sf_list *psf;
 893	int i, scount;
 894
 895	if (pmc->sfmode == MCAST_EXCLUDE)
 896		return igmp_xmarksources(pmc, nsrcs, srcs);
 897
 898	/* mark INCLUDE-mode sources */
 899	scount = 0;
 900	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 901		if (scount == nsrcs)
 902			break;
 903		for (i = 0; i < nsrcs; i++)
 904			if (srcs[i] == psf->sf_inaddr) {
 905				psf->sf_gsresp = 1;
 906				scount++;
 907				break;
 908			}
 909	}
 910	if (!scount) {
 911		pmc->gsquery = 0;
 912		return 0;
 913	}
 914	pmc->gsquery = 1;
 915	return 1;
 916}
 917
 918/* return true if packet was dropped */
 919static bool igmp_heard_report(struct in_device *in_dev, __be32 group)
 920{
 921	struct ip_mc_list *im;
 922	struct net *net = dev_net(in_dev->dev);
 923
 924	/* Timers are only set for non-local groups */
 925
 926	if (group == IGMP_ALL_HOSTS)
 927		return false;
 928	if (ipv4_is_local_multicast(group) &&
 929	    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
 930		return false;
 931
 932	rcu_read_lock();
 933	for_each_pmc_rcu(in_dev, im) {
 934		if (im->multiaddr == group) {
 935			igmp_stop_timer(im);
 936			break;
 937		}
 938	}
 939	rcu_read_unlock();
 940	return false;
 941}
 942
 943/* return true if packet was dropped */
 944static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
 945	int len)
 946{
 947	struct igmphdr 		*ih = igmp_hdr(skb);
 948	struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
 949	struct ip_mc_list	*im;
 950	__be32			group = ih->group;
 951	int			max_delay;
 952	int			mark = 0;
 953	struct net		*net = dev_net(in_dev->dev);
 954
 955
 956	if (len == 8) {
 957		if (ih->code == 0) {
 958			/* Alas, old v1 router presents here. */
 959
 960			max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 961			in_dev->mr_v1_seen = jiffies +
 962				(in_dev->mr_qrv * in_dev->mr_qi) +
 963				in_dev->mr_qri;
 964			group = 0;
 965		} else {
 966			/* v2 router present */
 967			max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
 968			in_dev->mr_v2_seen = jiffies +
 969				(in_dev->mr_qrv * in_dev->mr_qi) +
 970				in_dev->mr_qri;
 971		}
 972		/* cancel the interface change timer */
 973		WRITE_ONCE(in_dev->mr_ifc_count, 0);
 974		if (del_timer(&in_dev->mr_ifc_timer))
 975			__in_dev_put(in_dev);
 976		/* clear deleted report items */
 977		igmpv3_clear_delrec(in_dev);
 978	} else if (len < 12) {
 979		return true;	/* ignore bogus packet; freed by caller */
 980	} else if (IGMP_V1_SEEN(in_dev)) {
 981		/* This is a v3 query with v1 queriers present */
 982		max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 983		group = 0;
 984	} else if (IGMP_V2_SEEN(in_dev)) {
 985		/* this is a v3 query with v2 queriers present;
 986		 * Interpretation of the max_delay code is problematic here.
 987		 * A real v2 host would use ih_code directly, while v3 has a
 988		 * different encoding. We use the v3 encoding as more likely
 989		 * to be intended in a v3 query.
 990		 */
 991		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 992		if (!max_delay)
 993			max_delay = 1;	/* can't mod w/ 0 */
 994	} else { /* v3 */
 995		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
 996			return true;
 997
 998		ih3 = igmpv3_query_hdr(skb);
 999		if (ih3->nsrcs) {
1000			if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
1001					   + ntohs(ih3->nsrcs)*sizeof(__be32)))
1002				return true;
1003			ih3 = igmpv3_query_hdr(skb);
1004		}
1005
1006		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
1007		if (!max_delay)
1008			max_delay = 1;	/* can't mod w/ 0 */
1009		in_dev->mr_maxdelay = max_delay;
1010
1011		/* RFC3376, 4.1.6. QRV and 4.1.7. QQIC, when the most recently
1012		 * received value was zero, use the default or statically
1013		 * configured value.
1014		 */
1015		in_dev->mr_qrv = ih3->qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1016		in_dev->mr_qi = IGMPV3_QQIC(ih3->qqic)*HZ ?: IGMP_QUERY_INTERVAL;
1017
1018		/* RFC3376, 8.3. Query Response Interval:
1019		 * The number of seconds represented by the [Query Response
1020		 * Interval] must be less than the [Query Interval].
1021		 */
1022		if (in_dev->mr_qri >= in_dev->mr_qi)
1023			in_dev->mr_qri = (in_dev->mr_qi/HZ - 1)*HZ;
1024
1025		if (!group) { /* general query */
1026			if (ih3->nsrcs)
1027				return true;	/* no sources allowed */
1028			igmp_gq_start_timer(in_dev);
1029			return false;
1030		}
1031		/* mark sources to include, if group & source-specific */
1032		mark = ih3->nsrcs != 0;
1033	}
1034
1035	/*
1036	 * - Start the timers in all of our membership records
1037	 *   that the query applies to for the interface on
1038	 *   which the query arrived excl. those that belong
1039	 *   to a "local" group (224.0.0.X)
1040	 * - For timers already running check if they need to
1041	 *   be reset.
1042	 * - Use the igmp->igmp_code field as the maximum
1043	 *   delay possible
1044	 */
1045	rcu_read_lock();
1046	for_each_pmc_rcu(in_dev, im) {
1047		int changed;
1048
1049		if (group && group != im->multiaddr)
1050			continue;
1051		if (im->multiaddr == IGMP_ALL_HOSTS)
1052			continue;
1053		if (ipv4_is_local_multicast(im->multiaddr) &&
1054		    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
1055			continue;
1056		spin_lock_bh(&im->lock);
1057		if (im->tm_running)
1058			im->gsquery = im->gsquery && mark;
1059		else
1060			im->gsquery = mark;
1061		changed = !im->gsquery ||
1062			igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
1063		spin_unlock_bh(&im->lock);
1064		if (changed)
1065			igmp_mod_timer(im, max_delay);
1066	}
1067	rcu_read_unlock();
1068	return false;
1069}
1070
1071/* called in rcu_read_lock() section */
1072int igmp_rcv(struct sk_buff *skb)
1073{
1074	/* This basically follows the spec line by line -- see RFC1112 */
1075	struct igmphdr *ih;
1076	struct net_device *dev = skb->dev;
1077	struct in_device *in_dev;
1078	int len = skb->len;
1079	bool dropped = true;
1080
1081	if (netif_is_l3_master(dev)) {
1082		dev = dev_get_by_index_rcu(dev_net(dev), IPCB(skb)->iif);
1083		if (!dev)
1084			goto drop;
1085	}
1086
1087	in_dev = __in_dev_get_rcu(dev);
1088	if (!in_dev)
1089		goto drop;
1090
1091	if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
1092		goto drop;
1093
1094	if (skb_checksum_simple_validate(skb))
1095		goto drop;
1096
1097	ih = igmp_hdr(skb);
1098	switch (ih->type) {
1099	case IGMP_HOST_MEMBERSHIP_QUERY:
1100		dropped = igmp_heard_query(in_dev, skb, len);
1101		break;
1102	case IGMP_HOST_MEMBERSHIP_REPORT:
1103	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1104		/* Is it our report looped back? */
1105		if (rt_is_output_route(skb_rtable(skb)))
1106			break;
1107		/* don't rely on MC router hearing unicast reports */
1108		if (skb->pkt_type == PACKET_MULTICAST ||
1109		    skb->pkt_type == PACKET_BROADCAST)
1110			dropped = igmp_heard_report(in_dev, ih->group);
1111		break;
1112	case IGMP_PIM:
1113#ifdef CONFIG_IP_PIMSM_V1
1114		return pim_rcv_v1(skb);
1115#endif
1116	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1117	case IGMP_DVMRP:
1118	case IGMP_TRACE:
1119	case IGMP_HOST_LEAVE_MESSAGE:
1120	case IGMP_MTRACE:
1121	case IGMP_MTRACE_RESP:
1122		break;
1123	default:
1124		break;
1125	}
1126
1127drop:
1128	if (dropped)
1129		kfree_skb(skb);
1130	else
1131		consume_skb(skb);
1132	return 0;
1133}
1134
1135#endif
1136
1137
1138/*
1139 *	Add a filter to a device
1140 */
1141
1142static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1143{
1144	char buf[MAX_ADDR_LEN];
1145	struct net_device *dev = in_dev->dev;
1146
1147	/* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1148	   We will get multicast token leakage, when IFF_MULTICAST
1149	   is changed. This check should be done in ndo_set_rx_mode
1150	   routine. Something sort of:
1151	   if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1152	   --ANK
1153	   */
1154	if (arp_mc_map(addr, buf, dev, 0) == 0)
1155		dev_mc_add(dev, buf);
1156}
1157
1158/*
1159 *	Remove a filter from a device
1160 */
1161
1162static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1163{
1164	char buf[MAX_ADDR_LEN];
1165	struct net_device *dev = in_dev->dev;
1166
1167	if (arp_mc_map(addr, buf, dev, 0) == 0)
1168		dev_mc_del(dev, buf);
1169}
1170
1171#ifdef CONFIG_IP_MULTICAST
1172/*
1173 * deleted ip_mc_list manipulation
1174 */
1175static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im,
1176			      gfp_t gfp)
1177{
1178	struct ip_mc_list *pmc;
1179	struct net *net = dev_net(in_dev->dev);
1180
1181	/* this is an "ip_mc_list" for convenience; only the fields below
1182	 * are actually used. In particular, the refcnt and users are not
1183	 * used for management of the delete list. Using the same structure
1184	 * for deleted items allows change reports to use common code with
1185	 * non-deleted or query-response MCA's.
1186	 */
1187	pmc = kzalloc(sizeof(*pmc), gfp);
1188	if (!pmc)
1189		return;
1190	spin_lock_init(&pmc->lock);
1191	spin_lock_bh(&im->lock);
1192	pmc->interface = im->interface;
1193	in_dev_hold(in_dev);
1194	pmc->multiaddr = im->multiaddr;
1195	pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1196	pmc->sfmode = im->sfmode;
1197	if (pmc->sfmode == MCAST_INCLUDE) {
1198		struct ip_sf_list *psf;
1199
1200		pmc->tomb = im->tomb;
1201		pmc->sources = im->sources;
1202		im->tomb = im->sources = NULL;
1203		for (psf = pmc->sources; psf; psf = psf->sf_next)
1204			psf->sf_crcount = pmc->crcount;
1205	}
1206	spin_unlock_bh(&im->lock);
1207
1208	spin_lock_bh(&in_dev->mc_tomb_lock);
1209	pmc->next = in_dev->mc_tomb;
1210	in_dev->mc_tomb = pmc;
1211	spin_unlock_bh(&in_dev->mc_tomb_lock);
1212}
1213
1214/*
1215 * restore ip_mc_list deleted records
1216 */
1217static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1218{
1219	struct ip_mc_list *pmc, *pmc_prev;
1220	struct ip_sf_list *psf;
1221	struct net *net = dev_net(in_dev->dev);
1222	__be32 multiaddr = im->multiaddr;
1223
1224	spin_lock_bh(&in_dev->mc_tomb_lock);
1225	pmc_prev = NULL;
1226	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) {
1227		if (pmc->multiaddr == multiaddr)
1228			break;
1229		pmc_prev = pmc;
1230	}
1231	if (pmc) {
1232		if (pmc_prev)
1233			pmc_prev->next = pmc->next;
1234		else
1235			in_dev->mc_tomb = pmc->next;
1236	}
1237	spin_unlock_bh(&in_dev->mc_tomb_lock);
1238
1239	spin_lock_bh(&im->lock);
1240	if (pmc) {
1241		im->interface = pmc->interface;
1242		if (im->sfmode == MCAST_INCLUDE) {
1243			swap(im->tomb, pmc->tomb);
1244			swap(im->sources, pmc->sources);
 
 
1245			for (psf = im->sources; psf; psf = psf->sf_next)
1246				psf->sf_crcount = in_dev->mr_qrv ?:
1247					READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1248		} else {
1249			im->crcount = in_dev->mr_qrv ?:
1250				READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1251		}
1252		in_dev_put(pmc->interface);
1253		kfree_pmc(pmc);
1254	}
1255	spin_unlock_bh(&im->lock);
1256}
1257
1258/*
1259 * flush ip_mc_list deleted records
1260 */
1261static void igmpv3_clear_delrec(struct in_device *in_dev)
1262{
1263	struct ip_mc_list *pmc, *nextpmc;
1264
1265	spin_lock_bh(&in_dev->mc_tomb_lock);
1266	pmc = in_dev->mc_tomb;
1267	in_dev->mc_tomb = NULL;
1268	spin_unlock_bh(&in_dev->mc_tomb_lock);
1269
1270	for (; pmc; pmc = nextpmc) {
1271		nextpmc = pmc->next;
1272		ip_mc_clear_src(pmc);
1273		in_dev_put(pmc->interface);
1274		kfree_pmc(pmc);
1275	}
1276	/* clear dead sources, too */
1277	rcu_read_lock();
1278	for_each_pmc_rcu(in_dev, pmc) {
1279		struct ip_sf_list *psf;
1280
1281		spin_lock_bh(&pmc->lock);
1282		psf = pmc->tomb;
1283		pmc->tomb = NULL;
1284		spin_unlock_bh(&pmc->lock);
1285		ip_sf_list_clear_all(psf);
 
 
 
1286	}
1287	rcu_read_unlock();
1288}
1289#endif
1290
1291static void __igmp_group_dropped(struct ip_mc_list *im, gfp_t gfp)
1292{
1293	struct in_device *in_dev = im->interface;
1294#ifdef CONFIG_IP_MULTICAST
1295	struct net *net = dev_net(in_dev->dev);
1296	int reporter;
1297#endif
1298
1299	if (im->loaded) {
1300		im->loaded = 0;
1301		ip_mc_filter_del(in_dev, im->multiaddr);
1302	}
1303
1304#ifdef CONFIG_IP_MULTICAST
1305	if (im->multiaddr == IGMP_ALL_HOSTS)
1306		return;
1307	if (ipv4_is_local_multicast(im->multiaddr) &&
1308	    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
1309		return;
1310
1311	reporter = im->reporter;
1312	igmp_stop_timer(im);
1313
1314	if (!in_dev->dead) {
1315		if (IGMP_V1_SEEN(in_dev))
1316			return;
1317		if (IGMP_V2_SEEN(in_dev)) {
1318			if (reporter)
1319				igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1320			return;
1321		}
1322		/* IGMPv3 */
1323		igmpv3_add_delrec(in_dev, im, gfp);
1324
1325		igmp_ifc_event(in_dev);
1326	}
1327#endif
1328}
1329
1330static void igmp_group_dropped(struct ip_mc_list *im)
1331{
1332	__igmp_group_dropped(im, GFP_KERNEL);
1333}
1334
1335static void igmp_group_added(struct ip_mc_list *im)
1336{
1337	struct in_device *in_dev = im->interface;
1338#ifdef CONFIG_IP_MULTICAST
1339	struct net *net = dev_net(in_dev->dev);
1340#endif
1341
1342	if (im->loaded == 0) {
1343		im->loaded = 1;
1344		ip_mc_filter_add(in_dev, im->multiaddr);
1345	}
1346
1347#ifdef CONFIG_IP_MULTICAST
1348	if (im->multiaddr == IGMP_ALL_HOSTS)
1349		return;
1350	if (ipv4_is_local_multicast(im->multiaddr) &&
1351	    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
1352		return;
1353
1354	if (in_dev->dead)
1355		return;
1356
1357	im->unsolicit_count = READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1358	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1359		spin_lock_bh(&im->lock);
1360		igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY);
1361		spin_unlock_bh(&im->lock);
1362		return;
1363	}
1364	/* else, v3 */
1365
1366	/* Based on RFC3376 5.1, for newly added INCLUDE SSM, we should
1367	 * not send filter-mode change record as the mode should be from
1368	 * IN() to IN(A).
1369	 */
1370	if (im->sfmode == MCAST_EXCLUDE)
1371		im->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1372
1373	igmp_ifc_event(in_dev);
1374#endif
1375}
1376
1377
1378/*
1379 *	Multicast list managers
1380 */
1381
1382static u32 ip_mc_hash(const struct ip_mc_list *im)
1383{
1384	return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
1385}
1386
1387static void ip_mc_hash_add(struct in_device *in_dev,
1388			   struct ip_mc_list *im)
1389{
1390	struct ip_mc_list __rcu **mc_hash;
1391	u32 hash;
1392
1393	mc_hash = rtnl_dereference(in_dev->mc_hash);
1394	if (mc_hash) {
1395		hash = ip_mc_hash(im);
1396		im->next_hash = mc_hash[hash];
1397		rcu_assign_pointer(mc_hash[hash], im);
1398		return;
1399	}
1400
1401	/* do not use a hash table for small number of items */
1402	if (in_dev->mc_count < 4)
1403		return;
1404
1405	mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
1406			  GFP_KERNEL);
1407	if (!mc_hash)
1408		return;
1409
1410	for_each_pmc_rtnl(in_dev, im) {
1411		hash = ip_mc_hash(im);
1412		im->next_hash = mc_hash[hash];
1413		RCU_INIT_POINTER(mc_hash[hash], im);
1414	}
1415
1416	rcu_assign_pointer(in_dev->mc_hash, mc_hash);
1417}
1418
1419static void ip_mc_hash_remove(struct in_device *in_dev,
1420			      struct ip_mc_list *im)
1421{
1422	struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
1423	struct ip_mc_list *aux;
1424
1425	if (!mc_hash)
1426		return;
1427	mc_hash += ip_mc_hash(im);
1428	while ((aux = rtnl_dereference(*mc_hash)) != im)
1429		mc_hash = &aux->next_hash;
1430	*mc_hash = im->next_hash;
1431}
1432
1433
1434/*
1435 *	A socket has joined a multicast group on device dev.
1436 */
1437static void ____ip_mc_inc_group(struct in_device *in_dev, __be32 addr,
1438				unsigned int mode, gfp_t gfp)
1439{
1440	struct ip_mc_list __rcu **mc_hash;
1441	struct ip_mc_list *im;
 
 
 
1442
1443	ASSERT_RTNL();
1444
1445	mc_hash = rtnl_dereference(in_dev->mc_hash);
1446	if (mc_hash) {
1447		u32 hash = hash_32((__force u32)addr, MC_HASH_SZ_LOG);
1448
1449		for (im = rtnl_dereference(mc_hash[hash]);
1450		     im;
1451		     im = rtnl_dereference(im->next_hash)) {
1452			if (im->multiaddr == addr)
1453				break;
1454		}
1455	} else {
1456		for_each_pmc_rtnl(in_dev, im) {
1457			if (im->multiaddr == addr)
1458				break;
1459		}
1460	}
1461
1462	if  (im) {
1463		im->users++;
1464		ip_mc_add_src(in_dev, &addr, mode, 0, NULL, 0);
1465		goto out;
1466	}
1467
1468	im = kzalloc(sizeof(*im), gfp);
1469	if (!im)
1470		goto out;
1471
1472	im->users = 1;
1473	im->interface = in_dev;
1474	in_dev_hold(in_dev);
1475	im->multiaddr = addr;
1476	/* initial mode is (EX, empty) */
1477	im->sfmode = mode;
1478	im->sfcount[mode] = 1;
1479	refcount_set(&im->refcnt, 1);
1480	spin_lock_init(&im->lock);
1481#ifdef CONFIG_IP_MULTICAST
1482	timer_setup(&im->timer, igmp_timer_expire, 0);
 
1483#endif
1484
1485	im->next_rcu = in_dev->mc_list;
1486	in_dev->mc_count++;
1487	rcu_assign_pointer(in_dev->mc_list, im);
1488
1489	ip_mc_hash_add(in_dev, im);
1490
1491#ifdef CONFIG_IP_MULTICAST
1492	igmpv3_del_delrec(in_dev, im);
1493#endif
1494	igmp_group_added(im);
1495	if (!in_dev->dead)
1496		ip_rt_multicast_event(in_dev);
1497out:
1498	return;
1499}
1500
1501void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr, gfp_t gfp)
1502{
1503	____ip_mc_inc_group(in_dev, addr, MCAST_EXCLUDE, gfp);
1504}
1505EXPORT_SYMBOL(__ip_mc_inc_group);
1506
1507void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1508{
1509	__ip_mc_inc_group(in_dev, addr, GFP_KERNEL);
1510}
1511EXPORT_SYMBOL(ip_mc_inc_group);
1512
1513static int ip_mc_check_iphdr(struct sk_buff *skb)
1514{
1515	const struct iphdr *iph;
1516	unsigned int len;
1517	unsigned int offset = skb_network_offset(skb) + sizeof(*iph);
1518
1519	if (!pskb_may_pull(skb, offset))
1520		return -EINVAL;
1521
1522	iph = ip_hdr(skb);
1523
1524	if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph))
1525		return -EINVAL;
1526
1527	offset += ip_hdrlen(skb) - sizeof(*iph);
1528
1529	if (!pskb_may_pull(skb, offset))
1530		return -EINVAL;
1531
1532	iph = ip_hdr(skb);
1533
1534	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1535		return -EINVAL;
1536
1537	len = skb_network_offset(skb) + ntohs(iph->tot_len);
1538	if (skb->len < len || len < offset)
1539		return -EINVAL;
1540
1541	skb_set_transport_header(skb, offset);
1542
1543	return 0;
1544}
1545
1546static int ip_mc_check_igmp_reportv3(struct sk_buff *skb)
1547{
1548	unsigned int len = skb_transport_offset(skb);
1549
1550	len += sizeof(struct igmpv3_report);
1551
1552	return ip_mc_may_pull(skb, len) ? 0 : -EINVAL;
1553}
1554
1555static int ip_mc_check_igmp_query(struct sk_buff *skb)
1556{
1557	unsigned int transport_len = ip_transport_len(skb);
1558	unsigned int len;
 
 
 
1559
1560	/* IGMPv{1,2}? */
1561	if (transport_len != sizeof(struct igmphdr)) {
1562		/* or IGMPv3? */
1563		if (transport_len < sizeof(struct igmpv3_query))
1564			return -EINVAL;
1565
1566		len = skb_transport_offset(skb) + sizeof(struct igmpv3_query);
1567		if (!ip_mc_may_pull(skb, len))
1568			return -EINVAL;
1569	}
1570
1571	/* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1572	 * all-systems destination addresses (224.0.0.1) for general queries
1573	 */
1574	if (!igmp_hdr(skb)->group &&
1575	    ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP))
1576		return -EINVAL;
1577
1578	return 0;
1579}
1580
1581static int ip_mc_check_igmp_msg(struct sk_buff *skb)
1582{
1583	switch (igmp_hdr(skb)->type) {
1584	case IGMP_HOST_LEAVE_MESSAGE:
1585	case IGMP_HOST_MEMBERSHIP_REPORT:
1586	case IGMPV2_HOST_MEMBERSHIP_REPORT:
 
1587		return 0;
1588	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1589		return ip_mc_check_igmp_reportv3(skb);
1590	case IGMP_HOST_MEMBERSHIP_QUERY:
1591		return ip_mc_check_igmp_query(skb);
1592	default:
1593		return -ENOMSG;
1594	}
1595}
1596
1597static __sum16 ip_mc_validate_checksum(struct sk_buff *skb)
1598{
1599	return skb_checksum_simple_validate(skb);
1600}
1601
1602static int ip_mc_check_igmp_csum(struct sk_buff *skb)
 
1603{
1604	unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr);
1605	unsigned int transport_len = ip_transport_len(skb);
1606	struct sk_buff *skb_chk;
 
 
 
1607
1608	if (!ip_mc_may_pull(skb, len))
1609		return -EINVAL;
1610
1611	skb_chk = skb_checksum_trimmed(skb, transport_len,
1612				       ip_mc_validate_checksum);
1613	if (!skb_chk)
1614		return -EINVAL;
 
 
 
1615
1616	if (skb_chk != skb)
 
 
 
 
 
 
 
1617		kfree_skb(skb_chk);
1618
1619	return 0;
 
 
 
 
 
 
1620}
1621
1622/**
1623 * ip_mc_check_igmp - checks whether this is a sane IGMP packet
1624 * @skb: the skb to validate
 
1625 *
1626 * Checks whether an IPv4 packet is a valid IGMP packet. If so sets
1627 * skb transport header accordingly and returns zero.
1628 *
1629 * -EINVAL: A broken packet was detected, i.e. it violates some internet
1630 *  standard
1631 * -ENOMSG: IP header validation succeeded but it is not an IGMP packet.
1632 * -ENOMEM: A memory allocation failure happened.
1633 *
 
 
 
 
 
 
 
 
1634 * Caller needs to set the skb network header and free any returned skb if it
1635 * differs from the provided skb.
1636 */
1637int ip_mc_check_igmp(struct sk_buff *skb)
1638{
1639	int ret = ip_mc_check_iphdr(skb);
1640
1641	if (ret < 0)
1642		return ret;
1643
1644	if (ip_hdr(skb)->protocol != IPPROTO_IGMP)
1645		return -ENOMSG;
1646
1647	ret = ip_mc_check_igmp_csum(skb);
1648	if (ret < 0)
1649		return ret;
1650
1651	return ip_mc_check_igmp_msg(skb);
1652}
1653EXPORT_SYMBOL(ip_mc_check_igmp);
1654
1655/*
1656 *	Resend IGMP JOIN report; used by netdev notifier.
1657 */
1658static void ip_mc_rejoin_groups(struct in_device *in_dev)
1659{
1660#ifdef CONFIG_IP_MULTICAST
1661	struct ip_mc_list *im;
1662	int type;
1663	struct net *net = dev_net(in_dev->dev);
1664
1665	ASSERT_RTNL();
1666
1667	for_each_pmc_rtnl(in_dev, im) {
1668		if (im->multiaddr == IGMP_ALL_HOSTS)
1669			continue;
1670		if (ipv4_is_local_multicast(im->multiaddr) &&
1671		    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
1672			continue;
1673
1674		/* a failover is happening and switches
1675		 * must be notified immediately
1676		 */
1677		if (IGMP_V1_SEEN(in_dev))
1678			type = IGMP_HOST_MEMBERSHIP_REPORT;
1679		else if (IGMP_V2_SEEN(in_dev))
1680			type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1681		else
1682			type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1683		igmp_send_report(in_dev, im, type);
1684	}
1685#endif
1686}
1687
1688/*
1689 *	A socket has left a multicast group on device dev
1690 */
1691
1692void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp)
1693{
1694	struct ip_mc_list *i;
1695	struct ip_mc_list __rcu **ip;
1696
1697	ASSERT_RTNL();
1698
1699	for (ip = &in_dev->mc_list;
1700	     (i = rtnl_dereference(*ip)) != NULL;
1701	     ip = &i->next_rcu) {
1702		if (i->multiaddr == addr) {
1703			if (--i->users == 0) {
1704				ip_mc_hash_remove(in_dev, i);
1705				*ip = i->next_rcu;
1706				in_dev->mc_count--;
1707				__igmp_group_dropped(i, gfp);
1708				ip_mc_clear_src(i);
1709
1710				if (!in_dev->dead)
1711					ip_rt_multicast_event(in_dev);
1712
1713				ip_ma_put(i);
1714				return;
1715			}
1716			break;
1717		}
1718	}
1719}
1720EXPORT_SYMBOL(__ip_mc_dec_group);
1721
1722/* Device changing type */
1723
1724void ip_mc_unmap(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
1734void ip_mc_remap(struct in_device *in_dev)
1735{
1736	struct ip_mc_list *pmc;
1737
1738	ASSERT_RTNL();
1739
1740	for_each_pmc_rtnl(in_dev, pmc) {
1741#ifdef CONFIG_IP_MULTICAST
1742		igmpv3_del_delrec(in_dev, pmc);
1743#endif
1744		igmp_group_added(pmc);
1745	}
1746}
1747
1748/* Device going down */
1749
1750void ip_mc_down(struct in_device *in_dev)
1751{
1752	struct ip_mc_list *pmc;
1753
1754	ASSERT_RTNL();
1755
1756	for_each_pmc_rtnl(in_dev, pmc)
1757		igmp_group_dropped(pmc);
1758
1759#ifdef CONFIG_IP_MULTICAST
1760	WRITE_ONCE(in_dev->mr_ifc_count, 0);
1761	if (del_timer(&in_dev->mr_ifc_timer))
1762		__in_dev_put(in_dev);
1763	in_dev->mr_gq_running = 0;
1764	if (del_timer(&in_dev->mr_gq_timer))
1765		__in_dev_put(in_dev);
1766#endif
1767
1768	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1769}
1770
1771#ifdef CONFIG_IP_MULTICAST
1772static void ip_mc_reset(struct in_device *in_dev)
1773{
 
1774	struct net *net = dev_net(in_dev->dev);
1775
1776	in_dev->mr_qi = IGMP_QUERY_INTERVAL;
1777	in_dev->mr_qri = IGMP_QUERY_RESPONSE_INTERVAL;
1778	in_dev->mr_qrv = READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1779}
1780#else
1781static void ip_mc_reset(struct in_device *in_dev)
1782{
1783}
1784#endif
1785
1786void ip_mc_init_dev(struct in_device *in_dev)
1787{
1788	ASSERT_RTNL();
1789
1790#ifdef CONFIG_IP_MULTICAST
1791	timer_setup(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 0);
1792	timer_setup(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 0);
 
 
 
1793#endif
1794	ip_mc_reset(in_dev);
1795
1796	spin_lock_init(&in_dev->mc_tomb_lock);
1797}
1798
1799/* Device going up */
1800
1801void ip_mc_up(struct in_device *in_dev)
1802{
1803	struct ip_mc_list *pmc;
 
 
 
1804
1805	ASSERT_RTNL();
1806
1807	ip_mc_reset(in_dev);
 
 
1808	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1809
1810	for_each_pmc_rtnl(in_dev, pmc) {
1811#ifdef CONFIG_IP_MULTICAST
1812		igmpv3_del_delrec(in_dev, pmc);
1813#endif
1814		igmp_group_added(pmc);
1815	}
1816}
1817
1818/*
1819 *	Device is about to be destroyed: clean up.
1820 */
1821
1822void ip_mc_destroy_dev(struct in_device *in_dev)
1823{
1824	struct ip_mc_list *i;
1825
1826	ASSERT_RTNL();
1827
1828	/* Deactivate timers */
1829	ip_mc_down(in_dev);
1830#ifdef CONFIG_IP_MULTICAST
1831	igmpv3_clear_delrec(in_dev);
1832#endif
1833
1834	while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1835		in_dev->mc_list = i->next_rcu;
1836		in_dev->mc_count--;
1837		ip_mc_clear_src(i);
1838		ip_ma_put(i);
1839	}
1840}
1841
1842/* RTNL is locked */
1843static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1844{
1845	struct net_device *dev = NULL;
1846	struct in_device *idev = NULL;
1847
1848	if (imr->imr_ifindex) {
1849		idev = inetdev_by_index(net, imr->imr_ifindex);
1850		return idev;
1851	}
1852	if (imr->imr_address.s_addr) {
1853		dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1854		if (!dev)
1855			return NULL;
1856	}
1857
1858	if (!dev) {
1859		struct rtable *rt = ip_route_output(net,
1860						    imr->imr_multiaddr.s_addr,
1861						    0, 0, 0,
1862						    RT_SCOPE_UNIVERSE);
1863		if (!IS_ERR(rt)) {
1864			dev = rt->dst.dev;
1865			ip_rt_put(rt);
1866		}
1867	}
1868	if (dev) {
1869		imr->imr_ifindex = dev->ifindex;
1870		idev = __in_dev_get_rtnl(dev);
1871	}
1872	return idev;
1873}
1874
1875/*
1876 *	Join a socket to a group
1877 */
1878
1879static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1880	__be32 *psfsrc)
1881{
1882	struct ip_sf_list *psf, *psf_prev;
1883	int rv = 0;
1884
1885	psf_prev = NULL;
1886	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1887		if (psf->sf_inaddr == *psfsrc)
1888			break;
1889		psf_prev = psf;
1890	}
1891	if (!psf || psf->sf_count[sfmode] == 0) {
1892		/* source filter not found, or count wrong =>  bug */
1893		return -ESRCH;
1894	}
1895	psf->sf_count[sfmode]--;
1896	if (psf->sf_count[sfmode] == 0) {
1897		ip_rt_multicast_event(pmc->interface);
1898	}
1899	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1900#ifdef CONFIG_IP_MULTICAST
1901		struct in_device *in_dev = pmc->interface;
1902		struct net *net = dev_net(in_dev->dev);
1903#endif
1904
1905		/* no more filters for this source */
1906		if (psf_prev)
1907			psf_prev->sf_next = psf->sf_next;
1908		else
1909			pmc->sources = psf->sf_next;
1910#ifdef CONFIG_IP_MULTICAST
1911		if (psf->sf_oldin &&
1912		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1913			psf->sf_crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1914			psf->sf_next = pmc->tomb;
1915			pmc->tomb = psf;
1916			rv = 1;
1917		} else
1918#endif
1919			kfree(psf);
1920	}
1921	return rv;
1922}
1923
1924#ifndef CONFIG_IP_MULTICAST
1925#define igmp_ifc_event(x)	do { } while (0)
1926#endif
1927
1928static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1929			 int sfcount, __be32 *psfsrc, int delta)
1930{
1931	struct ip_mc_list *pmc;
1932	int	changerec = 0;
1933	int	i, err;
1934
1935	if (!in_dev)
1936		return -ENODEV;
1937	rcu_read_lock();
1938	for_each_pmc_rcu(in_dev, pmc) {
1939		if (*pmca == pmc->multiaddr)
1940			break;
1941	}
1942	if (!pmc) {
1943		/* MCA not found?? bug */
1944		rcu_read_unlock();
1945		return -ESRCH;
1946	}
1947	spin_lock_bh(&pmc->lock);
1948	rcu_read_unlock();
1949#ifdef CONFIG_IP_MULTICAST
1950	sf_markstate(pmc);
1951#endif
1952	if (!delta) {
1953		err = -EINVAL;
1954		if (!pmc->sfcount[sfmode])
1955			goto out_unlock;
1956		pmc->sfcount[sfmode]--;
1957	}
1958	err = 0;
1959	for (i = 0; i < sfcount; i++) {
1960		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1961
1962		changerec |= rv > 0;
1963		if (!err && rv < 0)
1964			err = rv;
1965	}
1966	if (pmc->sfmode == MCAST_EXCLUDE &&
1967	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1968	    pmc->sfcount[MCAST_INCLUDE]) {
1969#ifdef CONFIG_IP_MULTICAST
1970		struct ip_sf_list *psf;
1971		struct net *net = dev_net(in_dev->dev);
1972#endif
1973
1974		/* filter mode change */
1975		pmc->sfmode = MCAST_INCLUDE;
1976#ifdef CONFIG_IP_MULTICAST
1977		pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1978		WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount);
1979		for (psf = pmc->sources; psf; psf = psf->sf_next)
1980			psf->sf_crcount = 0;
1981		igmp_ifc_event(pmc->interface);
1982	} else if (sf_setstate(pmc) || changerec) {
1983		igmp_ifc_event(pmc->interface);
1984#endif
1985	}
1986out_unlock:
1987	spin_unlock_bh(&pmc->lock);
1988	return err;
1989}
1990
1991/*
1992 * Add multicast single-source filter to the interface list
1993 */
1994static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1995	__be32 *psfsrc)
1996{
1997	struct ip_sf_list *psf, *psf_prev;
1998
1999	psf_prev = NULL;
2000	for (psf = pmc->sources; psf; psf = psf->sf_next) {
2001		if (psf->sf_inaddr == *psfsrc)
2002			break;
2003		psf_prev = psf;
2004	}
2005	if (!psf) {
2006		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
2007		if (!psf)
2008			return -ENOBUFS;
2009		psf->sf_inaddr = *psfsrc;
2010		if (psf_prev) {
2011			psf_prev->sf_next = psf;
2012		} else
2013			pmc->sources = psf;
2014	}
2015	psf->sf_count[sfmode]++;
2016	if (psf->sf_count[sfmode] == 1) {
2017		ip_rt_multicast_event(pmc->interface);
2018	}
2019	return 0;
2020}
2021
2022#ifdef CONFIG_IP_MULTICAST
2023static void sf_markstate(struct ip_mc_list *pmc)
2024{
2025	struct ip_sf_list *psf;
2026	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
2027
2028	for (psf = pmc->sources; psf; psf = psf->sf_next)
2029		if (pmc->sfcount[MCAST_EXCLUDE]) {
2030			psf->sf_oldin = mca_xcount ==
2031				psf->sf_count[MCAST_EXCLUDE] &&
2032				!psf->sf_count[MCAST_INCLUDE];
2033		} else
2034			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2035}
2036
2037static int sf_setstate(struct ip_mc_list *pmc)
2038{
2039	struct ip_sf_list *psf, *dpsf;
2040	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
2041	int qrv = pmc->interface->mr_qrv;
2042	int new_in, rv;
2043
2044	rv = 0;
2045	for (psf = pmc->sources; psf; psf = psf->sf_next) {
2046		if (pmc->sfcount[MCAST_EXCLUDE]) {
2047			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2048				!psf->sf_count[MCAST_INCLUDE];
2049		} else
2050			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2051		if (new_in) {
2052			if (!psf->sf_oldin) {
2053				struct ip_sf_list *prev = NULL;
2054
2055				for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) {
2056					if (dpsf->sf_inaddr == psf->sf_inaddr)
2057						break;
2058					prev = dpsf;
2059				}
2060				if (dpsf) {
2061					if (prev)
2062						prev->sf_next = dpsf->sf_next;
2063					else
2064						pmc->tomb = dpsf->sf_next;
2065					kfree(dpsf);
2066				}
2067				psf->sf_crcount = qrv;
2068				rv++;
2069			}
2070		} else if (psf->sf_oldin) {
2071
2072			psf->sf_crcount = 0;
2073			/*
2074			 * add or update "delete" records if an active filter
2075			 * is now inactive
2076			 */
2077			for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next)
2078				if (dpsf->sf_inaddr == psf->sf_inaddr)
2079					break;
2080			if (!dpsf) {
2081				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
2082				if (!dpsf)
2083					continue;
2084				*dpsf = *psf;
2085				/* pmc->lock held by callers */
2086				dpsf->sf_next = pmc->tomb;
2087				pmc->tomb = dpsf;
2088			}
2089			dpsf->sf_crcount = qrv;
2090			rv++;
2091		}
2092	}
2093	return rv;
2094}
2095#endif
2096
2097/*
2098 * Add multicast source filter list to the interface list
2099 */
2100static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
2101			 int sfcount, __be32 *psfsrc, int delta)
2102{
2103	struct ip_mc_list *pmc;
2104	int	isexclude;
2105	int	i, err;
2106
2107	if (!in_dev)
2108		return -ENODEV;
2109	rcu_read_lock();
2110	for_each_pmc_rcu(in_dev, pmc) {
2111		if (*pmca == pmc->multiaddr)
2112			break;
2113	}
2114	if (!pmc) {
2115		/* MCA not found?? bug */
2116		rcu_read_unlock();
2117		return -ESRCH;
2118	}
2119	spin_lock_bh(&pmc->lock);
2120	rcu_read_unlock();
2121
2122#ifdef CONFIG_IP_MULTICAST
2123	sf_markstate(pmc);
2124#endif
2125	isexclude = pmc->sfmode == MCAST_EXCLUDE;
2126	if (!delta)
2127		pmc->sfcount[sfmode]++;
2128	err = 0;
2129	for (i = 0; i < sfcount; i++) {
2130		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2131		if (err)
2132			break;
2133	}
2134	if (err) {
2135		int j;
2136
2137		if (!delta)
2138			pmc->sfcount[sfmode]--;
2139		for (j = 0; j < i; j++)
2140			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2141	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
2142#ifdef CONFIG_IP_MULTICAST
2143		struct ip_sf_list *psf;
2144		struct net *net = dev_net(pmc->interface->dev);
2145		in_dev = pmc->interface;
2146#endif
2147
2148		/* filter mode change */
2149		if (pmc->sfcount[MCAST_EXCLUDE])
2150			pmc->sfmode = MCAST_EXCLUDE;
2151		else if (pmc->sfcount[MCAST_INCLUDE])
2152			pmc->sfmode = MCAST_INCLUDE;
2153#ifdef CONFIG_IP_MULTICAST
2154		/* else no filters; keep old mode for reports */
2155
2156		pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
2157		WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount);
2158		for (psf = pmc->sources; psf; psf = psf->sf_next)
2159			psf->sf_crcount = 0;
2160		igmp_ifc_event(in_dev);
2161	} else if (sf_setstate(pmc)) {
2162		igmp_ifc_event(in_dev);
2163#endif
2164	}
2165	spin_unlock_bh(&pmc->lock);
2166	return err;
2167}
2168
2169static void ip_mc_clear_src(struct ip_mc_list *pmc)
2170{
2171	struct ip_sf_list *tomb, *sources;
2172
2173	spin_lock_bh(&pmc->lock);
2174	tomb = pmc->tomb;
 
 
2175	pmc->tomb = NULL;
2176	sources = pmc->sources;
 
 
 
2177	pmc->sources = NULL;
2178	pmc->sfmode = MCAST_EXCLUDE;
2179	pmc->sfcount[MCAST_INCLUDE] = 0;
2180	pmc->sfcount[MCAST_EXCLUDE] = 1;
2181	spin_unlock_bh(&pmc->lock);
2182
2183	ip_sf_list_clear_all(tomb);
2184	ip_sf_list_clear_all(sources);
2185}
2186
2187/* Join a multicast group
2188 */
2189static int __ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr,
2190			      unsigned int mode)
2191{
2192	__be32 addr = imr->imr_multiaddr.s_addr;
2193	struct ip_mc_socklist *iml, *i;
2194	struct in_device *in_dev;
2195	struct inet_sock *inet = inet_sk(sk);
2196	struct net *net = sock_net(sk);
2197	int ifindex;
2198	int count = 0;
2199	int err;
2200
2201	ASSERT_RTNL();
2202
2203	if (!ipv4_is_multicast(addr))
2204		return -EINVAL;
2205
2206	in_dev = ip_mc_find_dev(net, imr);
2207
2208	if (!in_dev) {
2209		err = -ENODEV;
2210		goto done;
2211	}
2212
2213	err = -EADDRINUSE;
2214	ifindex = imr->imr_ifindex;
2215	for_each_pmc_rtnl(inet, i) {
2216		if (i->multi.imr_multiaddr.s_addr == addr &&
2217		    i->multi.imr_ifindex == ifindex)
2218			goto done;
2219		count++;
2220	}
2221	err = -ENOBUFS;
2222	if (count >= READ_ONCE(net->ipv4.sysctl_igmp_max_memberships))
2223		goto done;
2224	iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
2225	if (!iml)
2226		goto done;
2227
2228	memcpy(&iml->multi, imr, sizeof(*imr));
2229	iml->next_rcu = inet->mc_list;
2230	iml->sflist = NULL;
2231	iml->sfmode = mode;
2232	rcu_assign_pointer(inet->mc_list, iml);
2233	____ip_mc_inc_group(in_dev, addr, mode, GFP_KERNEL);
2234	err = 0;
2235done:
2236	return err;
2237}
2238
2239/* Join ASM (Any-Source Multicast) group
2240 */
2241int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
2242{
2243	return __ip_mc_join_group(sk, imr, MCAST_EXCLUDE);
2244}
2245EXPORT_SYMBOL(ip_mc_join_group);
2246
2247/* Join SSM (Source-Specific Multicast) group
2248 */
2249int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr,
2250			 unsigned int mode)
2251{
2252	return __ip_mc_join_group(sk, imr, mode);
2253}
2254
2255static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
2256			   struct in_device *in_dev)
2257{
2258	struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
2259	int err;
2260
2261	if (!psf) {
2262		/* any-source empty exclude case */
2263		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2264			iml->sfmode, 0, NULL, 0);
2265	}
2266	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2267			iml->sfmode, psf->sl_count, psf->sl_addr, 0);
2268	RCU_INIT_POINTER(iml->sflist, NULL);
2269	/* decrease mem now to avoid the memleak warning */
2270	atomic_sub(struct_size(psf, sl_addr, psf->sl_max), &sk->sk_omem_alloc);
2271	kfree_rcu(psf, rcu);
2272	return err;
2273}
2274
2275int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
2276{
2277	struct inet_sock *inet = inet_sk(sk);
2278	struct ip_mc_socklist *iml;
2279	struct ip_mc_socklist __rcu **imlp;
2280	struct in_device *in_dev;
2281	struct net *net = sock_net(sk);
2282	__be32 group = imr->imr_multiaddr.s_addr;
2283	u32 ifindex;
2284	int ret = -EADDRNOTAVAIL;
2285
2286	ASSERT_RTNL();
2287
2288	in_dev = ip_mc_find_dev(net, imr);
2289	if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) {
2290		ret = -ENODEV;
2291		goto out;
2292	}
2293	ifindex = imr->imr_ifindex;
2294	for (imlp = &inet->mc_list;
2295	     (iml = rtnl_dereference(*imlp)) != NULL;
2296	     imlp = &iml->next_rcu) {
2297		if (iml->multi.imr_multiaddr.s_addr != group)
2298			continue;
2299		if (ifindex) {
2300			if (iml->multi.imr_ifindex != ifindex)
2301				continue;
2302		} else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
2303				iml->multi.imr_address.s_addr)
2304			continue;
2305
2306		(void) ip_mc_leave_src(sk, iml, in_dev);
2307
2308		*imlp = iml->next_rcu;
2309
2310		if (in_dev)
2311			ip_mc_dec_group(in_dev, group);
2312
2313		/* decrease mem now to avoid the memleak warning */
2314		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2315		kfree_rcu(iml, rcu);
2316		return 0;
2317	}
2318out:
2319	return ret;
2320}
2321EXPORT_SYMBOL(ip_mc_leave_group);
2322
2323int ip_mc_source(int add, int omode, struct sock *sk, struct
2324	ip_mreq_source *mreqs, int ifindex)
2325{
2326	int err;
2327	struct ip_mreqn imr;
2328	__be32 addr = mreqs->imr_multiaddr;
2329	struct ip_mc_socklist *pmc;
2330	struct in_device *in_dev = NULL;
2331	struct inet_sock *inet = inet_sk(sk);
2332	struct ip_sf_socklist *psl;
2333	struct net *net = sock_net(sk);
2334	int leavegroup = 0;
2335	int i, j, rv;
2336
2337	if (!ipv4_is_multicast(addr))
2338		return -EINVAL;
2339
2340	ASSERT_RTNL();
2341
2342	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
2343	imr.imr_address.s_addr = mreqs->imr_interface;
2344	imr.imr_ifindex = ifindex;
2345	in_dev = ip_mc_find_dev(net, &imr);
2346
2347	if (!in_dev) {
2348		err = -ENODEV;
2349		goto done;
2350	}
2351	err = -EADDRNOTAVAIL;
2352
2353	for_each_pmc_rtnl(inet, pmc) {
2354		if ((pmc->multi.imr_multiaddr.s_addr ==
2355		     imr.imr_multiaddr.s_addr) &&
2356		    (pmc->multi.imr_ifindex == imr.imr_ifindex))
2357			break;
2358	}
2359	if (!pmc) {		/* must have a prior join */
2360		err = -EINVAL;
2361		goto done;
2362	}
2363	/* if a source filter was set, must be the same mode as before */
2364	if (pmc->sflist) {
2365		if (pmc->sfmode != omode) {
2366			err = -EINVAL;
2367			goto done;
2368		}
2369	} else if (pmc->sfmode != omode) {
2370		/* allow mode switches for empty-set filters */
2371		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
2372		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
2373			NULL, 0);
2374		pmc->sfmode = omode;
2375	}
2376
2377	psl = rtnl_dereference(pmc->sflist);
2378	if (!add) {
2379		if (!psl)
2380			goto done;	/* err = -EADDRNOTAVAIL */
2381		rv = !0;
2382		for (i = 0; i < psl->sl_count; i++) {
2383			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2384				sizeof(__be32));
2385			if (rv == 0)
2386				break;
2387		}
2388		if (rv)		/* source not found */
2389			goto done;	/* err = -EADDRNOTAVAIL */
2390
2391		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2392		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
2393			leavegroup = 1;
2394			goto done;
2395		}
2396
2397		/* update the interface filter */
2398		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2399			&mreqs->imr_sourceaddr, 1);
2400
2401		for (j = i+1; j < psl->sl_count; j++)
2402			psl->sl_addr[j-1] = psl->sl_addr[j];
2403		psl->sl_count--;
2404		err = 0;
2405		goto done;
2406	}
2407	/* else, add a new source to the filter */
2408
2409	if (psl && psl->sl_count >= READ_ONCE(net->ipv4.sysctl_igmp_max_msf)) {
2410		err = -ENOBUFS;
2411		goto done;
2412	}
2413	if (!psl || psl->sl_count == psl->sl_max) {
2414		struct ip_sf_socklist *newpsl;
2415		int count = IP_SFBLOCK;
2416
2417		if (psl)
2418			count += psl->sl_max;
2419		newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr, count),
2420				      GFP_KERNEL);
2421		if (!newpsl) {
2422			err = -ENOBUFS;
2423			goto done;
2424		}
2425		newpsl->sl_max = count;
2426		newpsl->sl_count = count - IP_SFBLOCK;
2427		if (psl) {
2428			for (i = 0; i < psl->sl_count; i++)
2429				newpsl->sl_addr[i] = psl->sl_addr[i];
2430			/* decrease mem now to avoid the memleak warning */
2431			atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
2432				   &sk->sk_omem_alloc);
2433		}
2434		rcu_assign_pointer(pmc->sflist, newpsl);
2435		if (psl)
2436			kfree_rcu(psl, rcu);
2437		psl = newpsl;
2438	}
2439	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
2440	for (i = 0; i < psl->sl_count; i++) {
2441		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2442			sizeof(__be32));
2443		if (rv == 0)
2444			break;
2445	}
2446	if (rv == 0)		/* address already there is an error */
2447		goto done;
2448	for (j = psl->sl_count-1; j >= i; j--)
2449		psl->sl_addr[j+1] = psl->sl_addr[j];
2450	psl->sl_addr[i] = mreqs->imr_sourceaddr;
2451	psl->sl_count++;
2452	err = 0;
2453	/* update the interface list */
2454	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2455		&mreqs->imr_sourceaddr, 1);
2456done:
2457	if (leavegroup)
2458		err = ip_mc_leave_group(sk, &imr);
2459	return err;
2460}
2461
2462int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2463{
2464	int err = 0;
2465	struct ip_mreqn	imr;
2466	__be32 addr = msf->imsf_multiaddr;
2467	struct ip_mc_socklist *pmc;
2468	struct in_device *in_dev;
2469	struct inet_sock *inet = inet_sk(sk);
2470	struct ip_sf_socklist *newpsl, *psl;
2471	struct net *net = sock_net(sk);
2472	int leavegroup = 0;
2473
2474	if (!ipv4_is_multicast(addr))
2475		return -EINVAL;
2476	if (msf->imsf_fmode != MCAST_INCLUDE &&
2477	    msf->imsf_fmode != MCAST_EXCLUDE)
2478		return -EINVAL;
2479
2480	ASSERT_RTNL();
2481
2482	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2483	imr.imr_address.s_addr = msf->imsf_interface;
2484	imr.imr_ifindex = ifindex;
2485	in_dev = ip_mc_find_dev(net, &imr);
2486
2487	if (!in_dev) {
2488		err = -ENODEV;
2489		goto done;
2490	}
2491
2492	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2493	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2494		leavegroup = 1;
2495		goto done;
2496	}
2497
2498	for_each_pmc_rtnl(inet, pmc) {
2499		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2500		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2501			break;
2502	}
2503	if (!pmc) {		/* must have a prior join */
2504		err = -EINVAL;
2505		goto done;
2506	}
2507	if (msf->imsf_numsrc) {
2508		newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr,
2509						      msf->imsf_numsrc),
2510				      GFP_KERNEL);
2511		if (!newpsl) {
2512			err = -ENOBUFS;
2513			goto done;
2514		}
2515		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2516		memcpy(newpsl->sl_addr, msf->imsf_slist_flex,
2517		       flex_array_size(msf, imsf_slist_flex, msf->imsf_numsrc));
2518		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2519			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2520		if (err) {
2521			sock_kfree_s(sk, newpsl,
2522				     struct_size(newpsl, sl_addr,
2523						 newpsl->sl_max));
2524			goto done;
2525		}
2526	} else {
2527		newpsl = NULL;
2528		(void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2529				     msf->imsf_fmode, 0, NULL, 0);
2530	}
2531	psl = rtnl_dereference(pmc->sflist);
2532	if (psl) {
2533		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2534			psl->sl_count, psl->sl_addr, 0);
2535		/* decrease mem now to avoid the memleak warning */
2536		atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
2537			   &sk->sk_omem_alloc);
2538	} else {
2539		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2540			0, NULL, 0);
2541	}
2542	rcu_assign_pointer(pmc->sflist, newpsl);
2543	if (psl)
2544		kfree_rcu(psl, rcu);
2545	pmc->sfmode = msf->imsf_fmode;
2546	err = 0;
2547done:
2548	if (leavegroup)
2549		err = ip_mc_leave_group(sk, &imr);
2550	return err;
2551}
 
2552int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2553		 sockptr_t optval, sockptr_t optlen)
2554{
2555	int err, len, count, copycount, msf_size;
2556	struct ip_mreqn	imr;
2557	__be32 addr = msf->imsf_multiaddr;
2558	struct ip_mc_socklist *pmc;
2559	struct in_device *in_dev;
2560	struct inet_sock *inet = inet_sk(sk);
2561	struct ip_sf_socklist *psl;
2562	struct net *net = sock_net(sk);
2563
2564	ASSERT_RTNL();
2565
2566	if (!ipv4_is_multicast(addr))
2567		return -EINVAL;
2568
2569	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2570	imr.imr_address.s_addr = msf->imsf_interface;
2571	imr.imr_ifindex = 0;
2572	in_dev = ip_mc_find_dev(net, &imr);
2573
2574	if (!in_dev) {
2575		err = -ENODEV;
2576		goto done;
2577	}
2578	err = -EADDRNOTAVAIL;
2579
2580	for_each_pmc_rtnl(inet, pmc) {
2581		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2582		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2583			break;
2584	}
2585	if (!pmc)		/* must have a prior join */
2586		goto done;
2587	msf->imsf_fmode = pmc->sfmode;
2588	psl = rtnl_dereference(pmc->sflist);
2589	if (!psl) {
 
2590		count = 0;
2591	} else {
2592		count = psl->sl_count;
2593	}
2594	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2595	len = flex_array_size(psl, sl_addr, copycount);
2596	msf->imsf_numsrc = count;
2597	msf_size = IP_MSFILTER_SIZE(copycount);
2598	if (copy_to_sockptr(optlen, &msf_size, sizeof(int)) ||
2599	    copy_to_sockptr(optval, msf, IP_MSFILTER_SIZE(0))) {
2600		return -EFAULT;
2601	}
2602	if (len &&
2603	    copy_to_sockptr_offset(optval,
2604				   offsetof(struct ip_msfilter, imsf_slist_flex),
2605				   psl->sl_addr, len))
2606		return -EFAULT;
2607	return 0;
2608done:
2609	return err;
2610}
2611
2612int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2613		 sockptr_t optval, size_t ss_offset)
2614{
2615	int i, count, copycount;
2616	struct sockaddr_in *psin;
2617	__be32 addr;
2618	struct ip_mc_socklist *pmc;
2619	struct inet_sock *inet = inet_sk(sk);
2620	struct ip_sf_socklist *psl;
2621
2622	ASSERT_RTNL();
2623
2624	psin = (struct sockaddr_in *)&gsf->gf_group;
2625	if (psin->sin_family != AF_INET)
2626		return -EINVAL;
2627	addr = psin->sin_addr.s_addr;
2628	if (!ipv4_is_multicast(addr))
2629		return -EINVAL;
2630
 
 
2631	for_each_pmc_rtnl(inet, pmc) {
2632		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2633		    pmc->multi.imr_ifindex == gsf->gf_interface)
2634			break;
2635	}
2636	if (!pmc)		/* must have a prior join */
2637		return -EADDRNOTAVAIL;
2638	gsf->gf_fmode = pmc->sfmode;
2639	psl = rtnl_dereference(pmc->sflist);
2640	count = psl ? psl->sl_count : 0;
2641	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2642	gsf->gf_numsrc = count;
 
 
 
 
2643	for (i = 0; i < copycount; i++) {
2644		struct sockaddr_storage ss;
2645
2646		psin = (struct sockaddr_in *)&ss;
2647		memset(&ss, 0, sizeof(ss));
2648		psin->sin_family = AF_INET;
2649		psin->sin_addr.s_addr = psl->sl_addr[i];
2650		if (copy_to_sockptr_offset(optval, ss_offset,
2651					   &ss, sizeof(ss)))
2652			return -EFAULT;
2653		ss_offset += sizeof(ss);
2654	}
2655	return 0;
 
 
2656}
2657
2658/*
2659 * check if a multicast source filter allows delivery for a given <src,dst,intf>
2660 */
2661int ip_mc_sf_allow(const struct sock *sk, __be32 loc_addr, __be32 rmt_addr,
2662		   int dif, int sdif)
2663{
2664	const struct inet_sock *inet = inet_sk(sk);
2665	struct ip_mc_socklist *pmc;
2666	struct ip_sf_socklist *psl;
2667	int i;
2668	int ret;
2669
2670	ret = 1;
2671	if (!ipv4_is_multicast(loc_addr))
2672		goto out;
2673
2674	rcu_read_lock();
2675	for_each_pmc_rcu(inet, pmc) {
2676		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2677		    (pmc->multi.imr_ifindex == dif ||
2678		     (sdif && pmc->multi.imr_ifindex == sdif)))
2679			break;
2680	}
2681	ret = inet_test_bit(MC_ALL, sk);
2682	if (!pmc)
2683		goto unlock;
2684	psl = rcu_dereference(pmc->sflist);
2685	ret = (pmc->sfmode == MCAST_EXCLUDE);
2686	if (!psl)
2687		goto unlock;
2688
2689	for (i = 0; i < psl->sl_count; i++) {
2690		if (psl->sl_addr[i] == rmt_addr)
2691			break;
2692	}
2693	ret = 0;
2694	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2695		goto unlock;
2696	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2697		goto unlock;
2698	ret = 1;
2699unlock:
2700	rcu_read_unlock();
2701out:
2702	return ret;
2703}
2704
2705/*
2706 *	A socket is closing.
2707 */
2708
2709void ip_mc_drop_socket(struct sock *sk)
2710{
2711	struct inet_sock *inet = inet_sk(sk);
2712	struct ip_mc_socklist *iml;
2713	struct net *net = sock_net(sk);
2714
2715	if (!inet->mc_list)
2716		return;
2717
2718	rtnl_lock();
2719	while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2720		struct in_device *in_dev;
2721
2722		inet->mc_list = iml->next_rcu;
2723		in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2724		(void) ip_mc_leave_src(sk, iml, in_dev);
2725		if (in_dev)
2726			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2727		/* decrease mem now to avoid the memleak warning */
2728		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2729		kfree_rcu(iml, rcu);
2730	}
2731	rtnl_unlock();
2732}
2733
2734/* called with rcu_read_lock() */
2735int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto)
2736{
2737	struct ip_mc_list *im;
2738	struct ip_mc_list __rcu **mc_hash;
2739	struct ip_sf_list *psf;
2740	int rv = 0;
2741
2742	mc_hash = rcu_dereference(in_dev->mc_hash);
2743	if (mc_hash) {
2744		u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
2745
2746		for (im = rcu_dereference(mc_hash[hash]);
2747		     im != NULL;
2748		     im = rcu_dereference(im->next_hash)) {
2749			if (im->multiaddr == mc_addr)
2750				break;
2751		}
2752	} else {
2753		for_each_pmc_rcu(in_dev, im) {
2754			if (im->multiaddr == mc_addr)
2755				break;
2756		}
2757	}
2758	if (im && proto == IPPROTO_IGMP) {
2759		rv = 1;
2760	} else if (im) {
2761		if (src_addr) {
2762			spin_lock_bh(&im->lock);
2763			for (psf = im->sources; psf; psf = psf->sf_next) {
2764				if (psf->sf_inaddr == src_addr)
2765					break;
2766			}
2767			if (psf)
2768				rv = psf->sf_count[MCAST_INCLUDE] ||
2769					psf->sf_count[MCAST_EXCLUDE] !=
2770					im->sfcount[MCAST_EXCLUDE];
2771			else
2772				rv = im->sfcount[MCAST_EXCLUDE] != 0;
2773			spin_unlock_bh(&im->lock);
2774		} else
2775			rv = 1; /* unspecified source; tentatively allow */
2776	}
2777	return rv;
2778}
2779
2780#if defined(CONFIG_PROC_FS)
2781struct igmp_mc_iter_state {
2782	struct seq_net_private p;
2783	struct net_device *dev;
2784	struct in_device *in_dev;
2785};
2786
2787#define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2788
2789static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2790{
2791	struct net *net = seq_file_net(seq);
2792	struct ip_mc_list *im = NULL;
2793	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2794
2795	state->in_dev = NULL;
2796	for_each_netdev_rcu(net, state->dev) {
2797		struct in_device *in_dev;
2798
2799		in_dev = __in_dev_get_rcu(state->dev);
2800		if (!in_dev)
2801			continue;
2802		im = rcu_dereference(in_dev->mc_list);
2803		if (im) {
2804			state->in_dev = in_dev;
2805			break;
2806		}
2807	}
2808	return im;
2809}
2810
2811static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2812{
2813	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2814
2815	im = rcu_dereference(im->next_rcu);
2816	while (!im) {
2817		state->dev = next_net_device_rcu(state->dev);
2818		if (!state->dev) {
2819			state->in_dev = NULL;
2820			break;
2821		}
2822		state->in_dev = __in_dev_get_rcu(state->dev);
2823		if (!state->in_dev)
2824			continue;
2825		im = rcu_dereference(state->in_dev->mc_list);
2826	}
2827	return im;
2828}
2829
2830static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2831{
2832	struct ip_mc_list *im = igmp_mc_get_first(seq);
2833	if (im)
2834		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2835			--pos;
2836	return pos ? NULL : im;
2837}
2838
2839static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2840	__acquires(rcu)
2841{
2842	rcu_read_lock();
2843	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2844}
2845
2846static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2847{
2848	struct ip_mc_list *im;
2849	if (v == SEQ_START_TOKEN)
2850		im = igmp_mc_get_first(seq);
2851	else
2852		im = igmp_mc_get_next(seq, v);
2853	++*pos;
2854	return im;
2855}
2856
2857static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2858	__releases(rcu)
2859{
2860	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2861
2862	state->in_dev = NULL;
2863	state->dev = NULL;
2864	rcu_read_unlock();
2865}
2866
2867static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2868{
2869	if (v == SEQ_START_TOKEN)
2870		seq_puts(seq,
2871			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2872	else {
2873		struct ip_mc_list *im = v;
2874		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2875		char   *querier;
2876		long delta;
2877
2878#ifdef CONFIG_IP_MULTICAST
2879		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2880			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2881			  "V3";
2882#else
2883		querier = "NONE";
2884#endif
2885
2886		if (rcu_access_pointer(state->in_dev->mc_list) == im) {
2887			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2888				   state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2889		}
2890
2891		delta = im->timer.expires - jiffies;
2892		seq_printf(seq,
2893			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2894			   im->multiaddr, im->users,
2895			   im->tm_running,
2896			   im->tm_running ? jiffies_delta_to_clock_t(delta) : 0,
2897			   im->reporter);
2898	}
2899	return 0;
2900}
2901
2902static const struct seq_operations igmp_mc_seq_ops = {
2903	.start	=	igmp_mc_seq_start,
2904	.next	=	igmp_mc_seq_next,
2905	.stop	=	igmp_mc_seq_stop,
2906	.show	=	igmp_mc_seq_show,
2907};
2908
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2909struct igmp_mcf_iter_state {
2910	struct seq_net_private p;
2911	struct net_device *dev;
2912	struct in_device *idev;
2913	struct ip_mc_list *im;
2914};
2915
2916#define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2917
2918static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2919{
2920	struct net *net = seq_file_net(seq);
2921	struct ip_sf_list *psf = NULL;
2922	struct ip_mc_list *im = NULL;
2923	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2924
2925	state->idev = NULL;
2926	state->im = NULL;
2927	for_each_netdev_rcu(net, state->dev) {
2928		struct in_device *idev;
2929		idev = __in_dev_get_rcu(state->dev);
2930		if (unlikely(!idev))
2931			continue;
2932		im = rcu_dereference(idev->mc_list);
2933		if (likely(im)) {
2934			spin_lock_bh(&im->lock);
2935			psf = im->sources;
2936			if (likely(psf)) {
2937				state->im = im;
2938				state->idev = idev;
2939				break;
2940			}
2941			spin_unlock_bh(&im->lock);
2942		}
2943	}
2944	return psf;
2945}
2946
2947static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2948{
2949	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2950
2951	psf = psf->sf_next;
2952	while (!psf) {
2953		spin_unlock_bh(&state->im->lock);
2954		state->im = state->im->next;
2955		while (!state->im) {
2956			state->dev = next_net_device_rcu(state->dev);
2957			if (!state->dev) {
2958				state->idev = NULL;
2959				goto out;
2960			}
2961			state->idev = __in_dev_get_rcu(state->dev);
2962			if (!state->idev)
2963				continue;
2964			state->im = rcu_dereference(state->idev->mc_list);
2965		}
 
 
2966		spin_lock_bh(&state->im->lock);
2967		psf = state->im->sources;
2968	}
2969out:
2970	return psf;
2971}
2972
2973static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2974{
2975	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2976	if (psf)
2977		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2978			--pos;
2979	return pos ? NULL : psf;
2980}
2981
2982static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2983	__acquires(rcu)
2984{
2985	rcu_read_lock();
2986	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2987}
2988
2989static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2990{
2991	struct ip_sf_list *psf;
2992	if (v == SEQ_START_TOKEN)
2993		psf = igmp_mcf_get_first(seq);
2994	else
2995		psf = igmp_mcf_get_next(seq, v);
2996	++*pos;
2997	return psf;
2998}
2999
3000static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
3001	__releases(rcu)
3002{
3003	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
3004	if (likely(state->im)) {
3005		spin_unlock_bh(&state->im->lock);
3006		state->im = NULL;
3007	}
3008	state->idev = NULL;
3009	state->dev = NULL;
3010	rcu_read_unlock();
3011}
3012
3013static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
3014{
3015	struct ip_sf_list *psf = v;
3016	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
3017
3018	if (v == SEQ_START_TOKEN) {
3019		seq_puts(seq, "Idx Device        MCA        SRC    INC    EXC\n");
3020	} else {
3021		seq_printf(seq,
3022			   "%3d %6.6s 0x%08x "
3023			   "0x%08x %6lu %6lu\n",
3024			   state->dev->ifindex, state->dev->name,
3025			   ntohl(state->im->multiaddr),
3026			   ntohl(psf->sf_inaddr),
3027			   psf->sf_count[MCAST_INCLUDE],
3028			   psf->sf_count[MCAST_EXCLUDE]);
3029	}
3030	return 0;
3031}
3032
3033static const struct seq_operations igmp_mcf_seq_ops = {
3034	.start	=	igmp_mcf_seq_start,
3035	.next	=	igmp_mcf_seq_next,
3036	.stop	=	igmp_mcf_seq_stop,
3037	.show	=	igmp_mcf_seq_show,
3038};
3039
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3040static int __net_init igmp_net_init(struct net *net)
3041{
3042	struct proc_dir_entry *pde;
3043	int err;
3044
3045	pde = proc_create_net("igmp", 0444, net->proc_net, &igmp_mc_seq_ops,
3046			sizeof(struct igmp_mc_iter_state));
3047	if (!pde)
3048		goto out_igmp;
3049	pde = proc_create_net("mcfilter", 0444, net->proc_net,
3050			&igmp_mcf_seq_ops, sizeof(struct igmp_mcf_iter_state));
3051	if (!pde)
3052		goto out_mcfilter;
3053	err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET,
3054				   SOCK_DGRAM, 0, net);
3055	if (err < 0) {
3056		pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n",
3057		       err);
3058		goto out_sock;
3059	}
3060
 
 
 
 
 
 
3061	return 0;
3062
3063out_sock:
3064	remove_proc_entry("mcfilter", net->proc_net);
3065out_mcfilter:
3066	remove_proc_entry("igmp", net->proc_net);
3067out_igmp:
3068	return -ENOMEM;
3069}
3070
3071static void __net_exit igmp_net_exit(struct net *net)
3072{
3073	remove_proc_entry("mcfilter", net->proc_net);
3074	remove_proc_entry("igmp", net->proc_net);
3075	inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk);
3076}
3077
3078static struct pernet_operations igmp_net_ops = {
3079	.init = igmp_net_init,
3080	.exit = igmp_net_exit,
3081};
3082#endif
3083
3084static int igmp_netdev_event(struct notifier_block *this,
3085			     unsigned long event, void *ptr)
3086{
3087	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3088	struct in_device *in_dev;
3089
3090	switch (event) {
3091	case NETDEV_RESEND_IGMP:
3092		in_dev = __in_dev_get_rtnl(dev);
3093		if (in_dev)
3094			ip_mc_rejoin_groups(in_dev);
3095		break;
3096	default:
3097		break;
3098	}
3099	return NOTIFY_DONE;
3100}
3101
3102static struct notifier_block igmp_notifier = {
3103	.notifier_call = igmp_netdev_event,
3104};
3105
3106int __init igmp_mc_init(void)
3107{
3108#if defined(CONFIG_PROC_FS)
3109	int err;
3110
3111	err = register_pernet_subsys(&igmp_net_ops);
3112	if (err)
3113		return err;
3114	err = register_netdevice_notifier(&igmp_notifier);
3115	if (err)
3116		goto reg_notif_fail;
3117	return 0;
3118
3119reg_notif_fail:
3120	unregister_pernet_subsys(&igmp_net_ops);
3121	return err;
3122#else
3123	return register_netdevice_notifier(&igmp_notifier);
3124#endif
3125}
v4.10.11
 
   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
  93#include <net/net_namespace.h>
  94#include <net/arp.h>
  95#include <net/ip.h>
  96#include <net/protocol.h>
  97#include <net/route.h>
  98#include <net/sock.h>
  99#include <net/checksum.h>
 100#include <net/inet_common.h>
 101#include <linux/netfilter_ipv4.h>
 102#ifdef CONFIG_IP_MROUTE
 103#include <linux/mroute.h>
 104#endif
 105#ifdef CONFIG_PROC_FS
 106#include <linux/proc_fs.h>
 107#include <linux/seq_file.h>
 108#endif
 109
 110#ifdef CONFIG_IP_MULTICAST
 111/* Parameter names and values are taken from igmp-v2-06 draft */
 112
 113#define IGMP_V1_ROUTER_PRESENT_TIMEOUT		(400*HZ)
 114#define IGMP_V2_ROUTER_PRESENT_TIMEOUT		(400*HZ)
 115#define IGMP_V2_UNSOLICITED_REPORT_INTERVAL	(10*HZ)
 116#define IGMP_V3_UNSOLICITED_REPORT_INTERVAL	(1*HZ)
 117#define IGMP_QUERY_RESPONSE_INTERVAL		(10*HZ)
 118#define IGMP_QUERY_ROBUSTNESS_VARIABLE		2
 119
 120
 121#define IGMP_INITIAL_REPORT_DELAY		(1)
 122
 123/* IGMP_INITIAL_REPORT_DELAY is not from IGMP specs!
 124 * IGMP specs require to report membership immediately after
 125 * joining a group, but we delay the first report by a
 126 * small interval. It seems more natural and still does not
 127 * contradict to specs provided this delay is small enough.
 128 */
 129
 130#define IGMP_V1_SEEN(in_dev) \
 131	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \
 132	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \
 133	 ((in_dev)->mr_v1_seen && \
 134	  time_before(jiffies, (in_dev)->mr_v1_seen)))
 135#define IGMP_V2_SEEN(in_dev) \
 136	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \
 137	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \
 138	 ((in_dev)->mr_v2_seen && \
 139	  time_before(jiffies, (in_dev)->mr_v2_seen)))
 140
 141static int unsolicited_report_interval(struct in_device *in_dev)
 142{
 143	int interval_ms, interval_jiffies;
 144
 145	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 146		interval_ms = IN_DEV_CONF_GET(
 147			in_dev,
 148			IGMPV2_UNSOLICITED_REPORT_INTERVAL);
 149	else /* v3 */
 150		interval_ms = IN_DEV_CONF_GET(
 151			in_dev,
 152			IGMPV3_UNSOLICITED_REPORT_INTERVAL);
 153
 154	interval_jiffies = msecs_to_jiffies(interval_ms);
 155
 156	/* _timer functions can't handle a delay of 0 jiffies so ensure
 157	 *  we always return a positive value.
 158	 */
 159	if (interval_jiffies <= 0)
 160		interval_jiffies = 1;
 161	return interval_jiffies;
 162}
 163
 164static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im);
 
 165static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im);
 166static void igmpv3_clear_delrec(struct in_device *in_dev);
 167static int sf_setstate(struct ip_mc_list *pmc);
 168static void sf_markstate(struct ip_mc_list *pmc);
 169#endif
 170static void ip_mc_clear_src(struct ip_mc_list *pmc);
 171static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
 172			 int sfcount, __be32 *psfsrc, int delta);
 173
 174static void ip_ma_put(struct ip_mc_list *im)
 175{
 176	if (atomic_dec_and_test(&im->refcnt)) {
 177		in_dev_put(im->interface);
 178		kfree_rcu(im, rcu);
 179	}
 180}
 181
 182#define for_each_pmc_rcu(in_dev, pmc)				\
 183	for (pmc = rcu_dereference(in_dev->mc_list);		\
 184	     pmc != NULL;					\
 185	     pmc = rcu_dereference(pmc->next_rcu))
 186
 187#define for_each_pmc_rtnl(in_dev, pmc)				\
 188	for (pmc = rtnl_dereference(in_dev->mc_list);		\
 189	     pmc != NULL;					\
 190	     pmc = rtnl_dereference(pmc->next_rcu))
 191
 
 
 
 
 
 
 
 
 
 
 
 192#ifdef CONFIG_IP_MULTICAST
 193
 194/*
 195 *	Timer management
 196 */
 197
 198static void igmp_stop_timer(struct ip_mc_list *im)
 199{
 200	spin_lock_bh(&im->lock);
 201	if (del_timer(&im->timer))
 202		atomic_dec(&im->refcnt);
 203	im->tm_running = 0;
 204	im->reporter = 0;
 205	im->unsolicit_count = 0;
 206	spin_unlock_bh(&im->lock);
 207}
 208
 209/* It must be called with locked im->lock */
 210static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
 211{
 212	int tv = prandom_u32() % max_delay;
 213
 214	im->tm_running = 1;
 215	if (!mod_timer(&im->timer, jiffies+tv+2))
 216		atomic_inc(&im->refcnt);
 
 
 217}
 218
 219static void igmp_gq_start_timer(struct in_device *in_dev)
 220{
 221	int tv = prandom_u32() % in_dev->mr_maxdelay;
 222	unsigned long exp = jiffies + tv + 2;
 223
 224	if (in_dev->mr_gq_running &&
 225	    time_after_eq(exp, (in_dev->mr_gq_timer).expires))
 226		return;
 227
 228	in_dev->mr_gq_running = 1;
 229	if (!mod_timer(&in_dev->mr_gq_timer, exp))
 230		in_dev_hold(in_dev);
 231}
 232
 233static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
 234{
 235	int tv = prandom_u32() % delay;
 236
 237	if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
 238		in_dev_hold(in_dev);
 239}
 240
 241static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
 242{
 243	spin_lock_bh(&im->lock);
 244	im->unsolicit_count = 0;
 245	if (del_timer(&im->timer)) {
 246		if ((long)(im->timer.expires-jiffies) < max_delay) {
 247			add_timer(&im->timer);
 248			im->tm_running = 1;
 249			spin_unlock_bh(&im->lock);
 250			return;
 251		}
 252		atomic_dec(&im->refcnt);
 253	}
 254	igmp_start_timer(im, max_delay);
 255	spin_unlock_bh(&im->lock);
 256}
 257
 258
 259/*
 260 *	Send an IGMP report.
 261 */
 262
 263#define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
 264
 265
 266static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
 267	int gdeleted, int sdeleted)
 268{
 269	switch (type) {
 270	case IGMPV3_MODE_IS_INCLUDE:
 271	case IGMPV3_MODE_IS_EXCLUDE:
 272		if (gdeleted || sdeleted)
 273			return 0;
 274		if (!(pmc->gsquery && !psf->sf_gsresp)) {
 275			if (pmc->sfmode == MCAST_INCLUDE)
 276				return 1;
 277			/* don't include if this source is excluded
 278			 * in all filters
 279			 */
 280			if (psf->sf_count[MCAST_INCLUDE])
 281				return type == IGMPV3_MODE_IS_INCLUDE;
 282			return pmc->sfcount[MCAST_EXCLUDE] ==
 283				psf->sf_count[MCAST_EXCLUDE];
 284		}
 285		return 0;
 286	case IGMPV3_CHANGE_TO_INCLUDE:
 287		if (gdeleted || sdeleted)
 288			return 0;
 289		return psf->sf_count[MCAST_INCLUDE] != 0;
 290	case IGMPV3_CHANGE_TO_EXCLUDE:
 291		if (gdeleted || sdeleted)
 292			return 0;
 293		if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
 294		    psf->sf_count[MCAST_INCLUDE])
 295			return 0;
 296		return pmc->sfcount[MCAST_EXCLUDE] ==
 297			psf->sf_count[MCAST_EXCLUDE];
 298	case IGMPV3_ALLOW_NEW_SOURCES:
 299		if (gdeleted || !psf->sf_crcount)
 300			return 0;
 301		return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
 302	case IGMPV3_BLOCK_OLD_SOURCES:
 303		if (pmc->sfmode == MCAST_INCLUDE)
 304			return gdeleted || (psf->sf_crcount && sdeleted);
 305		return psf->sf_crcount && !gdeleted && !sdeleted;
 306	}
 307	return 0;
 308}
 309
 310static int
 311igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
 312{
 313	struct ip_sf_list *psf;
 314	int scount = 0;
 315
 316	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 317		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
 318			continue;
 319		scount++;
 320	}
 321	return scount;
 322}
 323
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 324static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
 325{
 326	struct sk_buff *skb;
 327	struct rtable *rt;
 328	struct iphdr *pip;
 329	struct igmpv3_report *pig;
 330	struct net *net = dev_net(dev);
 331	struct flowi4 fl4;
 332	int hlen = LL_RESERVED_SPACE(dev);
 333	int tlen = dev->needed_tailroom;
 334	unsigned int size = mtu;
 335
 
 336	while (1) {
 337		skb = alloc_skb(size + hlen + tlen,
 338				GFP_ATOMIC | __GFP_NOWARN);
 339		if (skb)
 340			break;
 341		size >>= 1;
 342		if (size < 256)
 343			return NULL;
 344	}
 345	skb->priority = TC_PRIO_CONTROL;
 346
 347	rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0,
 348				   0, 0,
 349				   IPPROTO_IGMP, 0, dev->ifindex);
 350	if (IS_ERR(rt)) {
 351		kfree_skb(skb);
 352		return NULL;
 353	}
 354
 355	skb_dst_set(skb, &rt->dst);
 356	skb->dev = dev;
 357
 358	skb_reserve(skb, hlen);
 359	skb_tailroom_reserve(skb, mtu, tlen);
 360
 361	skb_reset_network_header(skb);
 362	pip = ip_hdr(skb);
 363	skb_put(skb, sizeof(struct iphdr) + 4);
 364
 365	pip->version  = 4;
 366	pip->ihl      = (sizeof(struct iphdr)+4)>>2;
 367	pip->tos      = 0xc0;
 368	pip->frag_off = htons(IP_DF);
 369	pip->ttl      = 1;
 370	pip->daddr    = fl4.daddr;
 371	pip->saddr    = fl4.saddr;
 
 
 
 
 372	pip->protocol = IPPROTO_IGMP;
 373	pip->tot_len  = 0;	/* filled in later */
 374	ip_select_ident(net, skb, NULL);
 375	((u8 *)&pip[1])[0] = IPOPT_RA;
 376	((u8 *)&pip[1])[1] = 4;
 377	((u8 *)&pip[1])[2] = 0;
 378	((u8 *)&pip[1])[3] = 0;
 379
 380	skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
 381	skb_put(skb, sizeof(*pig));
 382	pig = igmpv3_report_hdr(skb);
 383	pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
 384	pig->resv1 = 0;
 385	pig->csum = 0;
 386	pig->resv2 = 0;
 387	pig->ngrec = 0;
 388	return skb;
 389}
 390
 391static int igmpv3_sendpack(struct sk_buff *skb)
 392{
 393	struct igmphdr *pig = igmp_hdr(skb);
 394	const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
 395
 396	pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
 397
 398	return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
 399}
 400
 401static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
 402{
 403	return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
 404}
 405
 406static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
 407	int type, struct igmpv3_grec **ppgr)
 408{
 409	struct net_device *dev = pmc->interface->dev;
 410	struct igmpv3_report *pih;
 411	struct igmpv3_grec *pgr;
 412
 413	if (!skb)
 414		skb = igmpv3_newpack(dev, dev->mtu);
 415	if (!skb)
 416		return NULL;
 417	pgr = (struct igmpv3_grec *)skb_put(skb, sizeof(struct igmpv3_grec));
 
 418	pgr->grec_type = type;
 419	pgr->grec_auxwords = 0;
 420	pgr->grec_nsrcs = 0;
 421	pgr->grec_mca = pmc->multiaddr;
 422	pih = igmpv3_report_hdr(skb);
 423	pih->ngrec = htons(ntohs(pih->ngrec)+1);
 424	*ppgr = pgr;
 425	return skb;
 426}
 427
 428#define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
 429
 430static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
 431	int type, int gdeleted, int sdeleted)
 432{
 433	struct net_device *dev = pmc->interface->dev;
 434	struct net *net = dev_net(dev);
 435	struct igmpv3_report *pih;
 436	struct igmpv3_grec *pgr = NULL;
 437	struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
 438	int scount, stotal, first, isquery, truncate;
 
 439
 440	if (pmc->multiaddr == IGMP_ALL_HOSTS)
 441		return skb;
 442	if (ipv4_is_local_multicast(pmc->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
 
 
 
 
 
 443		return skb;
 444
 445	isquery = type == IGMPV3_MODE_IS_INCLUDE ||
 446		  type == IGMPV3_MODE_IS_EXCLUDE;
 447	truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
 448		    type == IGMPV3_CHANGE_TO_EXCLUDE;
 449
 450	stotal = scount = 0;
 451
 452	psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
 453
 454	if (!*psf_list)
 455		goto empty_source;
 456
 457	pih = skb ? igmpv3_report_hdr(skb) : NULL;
 458
 459	/* EX and TO_EX get a fresh packet, if needed */
 460	if (truncate) {
 461		if (pih && pih->ngrec &&
 462		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
 463			if (skb)
 464				igmpv3_sendpack(skb);
 465			skb = igmpv3_newpack(dev, dev->mtu);
 466		}
 467	}
 468	first = 1;
 469	psf_prev = NULL;
 470	for (psf = *psf_list; psf; psf = psf_next) {
 471		__be32 *psrc;
 472
 473		psf_next = psf->sf_next;
 474
 475		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
 476			psf_prev = psf;
 477			continue;
 478		}
 479
 480		/* Based on RFC3376 5.1. Should not send source-list change
 481		 * records when there is a filter mode change.
 482		 */
 483		if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) ||
 484		     (!gdeleted && pmc->crcount)) &&
 485		    (type == IGMPV3_ALLOW_NEW_SOURCES ||
 486		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount)
 487			goto decrease_sf_crcount;
 488
 489		/* clear marks on query responses */
 490		if (isquery)
 491			psf->sf_gsresp = 0;
 492
 493		if (AVAILABLE(skb) < sizeof(__be32) +
 494		    first*sizeof(struct igmpv3_grec)) {
 495			if (truncate && !first)
 496				break;	 /* truncate these */
 497			if (pgr)
 498				pgr->grec_nsrcs = htons(scount);
 499			if (skb)
 500				igmpv3_sendpack(skb);
 501			skb = igmpv3_newpack(dev, dev->mtu);
 502			first = 1;
 503			scount = 0;
 504		}
 505		if (first) {
 506			skb = add_grhead(skb, pmc, type, &pgr);
 507			first = 0;
 508		}
 509		if (!skb)
 510			return NULL;
 511		psrc = (__be32 *)skb_put(skb, sizeof(__be32));
 512		*psrc = psf->sf_inaddr;
 513		scount++; stotal++;
 514		if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
 515		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
 516decrease_sf_crcount:
 517			psf->sf_crcount--;
 518			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
 519				if (psf_prev)
 520					psf_prev->sf_next = psf->sf_next;
 521				else
 522					*psf_list = psf->sf_next;
 523				kfree(psf);
 524				continue;
 525			}
 526		}
 527		psf_prev = psf;
 528	}
 529
 530empty_source:
 531	if (!stotal) {
 532		if (type == IGMPV3_ALLOW_NEW_SOURCES ||
 533		    type == IGMPV3_BLOCK_OLD_SOURCES)
 534			return skb;
 535		if (pmc->crcount || isquery) {
 536			/* make sure we have room for group header */
 537			if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) {
 538				igmpv3_sendpack(skb);
 539				skb = NULL; /* add_grhead will get a new one */
 540			}
 541			skb = add_grhead(skb, pmc, type, &pgr);
 542		}
 543	}
 544	if (pgr)
 545		pgr->grec_nsrcs = htons(scount);
 546
 547	if (isquery)
 548		pmc->gsquery = 0;	/* clear query state on report */
 549	return skb;
 550}
 551
 552static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
 553{
 554	struct sk_buff *skb = NULL;
 555	struct net *net = dev_net(in_dev->dev);
 556	int type;
 557
 558	if (!pmc) {
 559		rcu_read_lock();
 560		for_each_pmc_rcu(in_dev, pmc) {
 561			if (pmc->multiaddr == IGMP_ALL_HOSTS)
 562				continue;
 563			if (ipv4_is_local_multicast(pmc->multiaddr) &&
 564			     !net->ipv4.sysctl_igmp_llm_reports)
 565				continue;
 566			spin_lock_bh(&pmc->lock);
 567			if (pmc->sfcount[MCAST_EXCLUDE])
 568				type = IGMPV3_MODE_IS_EXCLUDE;
 569			else
 570				type = IGMPV3_MODE_IS_INCLUDE;
 571			skb = add_grec(skb, pmc, type, 0, 0);
 572			spin_unlock_bh(&pmc->lock);
 573		}
 574		rcu_read_unlock();
 575	} else {
 576		spin_lock_bh(&pmc->lock);
 577		if (pmc->sfcount[MCAST_EXCLUDE])
 578			type = IGMPV3_MODE_IS_EXCLUDE;
 579		else
 580			type = IGMPV3_MODE_IS_INCLUDE;
 581		skb = add_grec(skb, pmc, type, 0, 0);
 582		spin_unlock_bh(&pmc->lock);
 583	}
 584	if (!skb)
 585		return 0;
 586	return igmpv3_sendpack(skb);
 587}
 588
 589/*
 590 * remove zero-count source records from a source filter list
 591 */
 592static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
 593{
 594	struct ip_sf_list *psf_prev, *psf_next, *psf;
 595
 596	psf_prev = NULL;
 597	for (psf = *ppsf; psf; psf = psf_next) {
 598		psf_next = psf->sf_next;
 599		if (psf->sf_crcount == 0) {
 600			if (psf_prev)
 601				psf_prev->sf_next = psf->sf_next;
 602			else
 603				*ppsf = psf->sf_next;
 604			kfree(psf);
 605		} else
 606			psf_prev = psf;
 607	}
 608}
 609
 
 
 
 
 
 
 
 610static void igmpv3_send_cr(struct in_device *in_dev)
 611{
 612	struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
 613	struct sk_buff *skb = NULL;
 614	int type, dtype;
 615
 616	rcu_read_lock();
 617	spin_lock_bh(&in_dev->mc_tomb_lock);
 618
 619	/* deleted MCA's */
 620	pmc_prev = NULL;
 621	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) {
 622		pmc_next = pmc->next;
 623		if (pmc->sfmode == MCAST_INCLUDE) {
 624			type = IGMPV3_BLOCK_OLD_SOURCES;
 625			dtype = IGMPV3_BLOCK_OLD_SOURCES;
 626			skb = add_grec(skb, pmc, type, 1, 0);
 627			skb = add_grec(skb, pmc, dtype, 1, 1);
 628		}
 629		if (pmc->crcount) {
 630			if (pmc->sfmode == MCAST_EXCLUDE) {
 631				type = IGMPV3_CHANGE_TO_INCLUDE;
 632				skb = add_grec(skb, pmc, type, 1, 0);
 633			}
 634			pmc->crcount--;
 635			if (pmc->crcount == 0) {
 636				igmpv3_clear_zeros(&pmc->tomb);
 637				igmpv3_clear_zeros(&pmc->sources);
 638			}
 639		}
 640		if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
 641			if (pmc_prev)
 642				pmc_prev->next = pmc_next;
 643			else
 644				in_dev->mc_tomb = pmc_next;
 645			in_dev_put(pmc->interface);
 646			kfree(pmc);
 647		} else
 648			pmc_prev = pmc;
 649	}
 650	spin_unlock_bh(&in_dev->mc_tomb_lock);
 651
 652	/* change recs */
 653	for_each_pmc_rcu(in_dev, pmc) {
 654		spin_lock_bh(&pmc->lock);
 655		if (pmc->sfcount[MCAST_EXCLUDE]) {
 656			type = IGMPV3_BLOCK_OLD_SOURCES;
 657			dtype = IGMPV3_ALLOW_NEW_SOURCES;
 658		} else {
 659			type = IGMPV3_ALLOW_NEW_SOURCES;
 660			dtype = IGMPV3_BLOCK_OLD_SOURCES;
 661		}
 662		skb = add_grec(skb, pmc, type, 0, 0);
 663		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
 664
 665		/* filter mode changes */
 666		if (pmc->crcount) {
 667			if (pmc->sfmode == MCAST_EXCLUDE)
 668				type = IGMPV3_CHANGE_TO_EXCLUDE;
 669			else
 670				type = IGMPV3_CHANGE_TO_INCLUDE;
 671			skb = add_grec(skb, pmc, type, 0, 0);
 672			pmc->crcount--;
 673		}
 674		spin_unlock_bh(&pmc->lock);
 675	}
 676	rcu_read_unlock();
 677
 678	if (!skb)
 679		return;
 680	(void) igmpv3_sendpack(skb);
 681}
 682
 683static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
 684	int type)
 685{
 686	struct sk_buff *skb;
 687	struct iphdr *iph;
 688	struct igmphdr *ih;
 689	struct rtable *rt;
 690	struct net_device *dev = in_dev->dev;
 691	struct net *net = dev_net(dev);
 692	__be32	group = pmc ? pmc->multiaddr : 0;
 693	struct flowi4 fl4;
 694	__be32	dst;
 695	int hlen, tlen;
 696
 697	if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
 698		return igmpv3_send_report(in_dev, pmc);
 699
 700	if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
 
 701		return 0;
 702
 703	if (type == IGMP_HOST_LEAVE_MESSAGE)
 704		dst = IGMP_ALL_ROUTER;
 705	else
 706		dst = group;
 707
 708	rt = ip_route_output_ports(net, &fl4, NULL, dst, 0,
 709				   0, 0,
 710				   IPPROTO_IGMP, 0, dev->ifindex);
 711	if (IS_ERR(rt))
 712		return -1;
 713
 714	hlen = LL_RESERVED_SPACE(dev);
 715	tlen = dev->needed_tailroom;
 716	skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC);
 717	if (!skb) {
 718		ip_rt_put(rt);
 719		return -1;
 720	}
 721	skb->priority = TC_PRIO_CONTROL;
 722
 723	skb_dst_set(skb, &rt->dst);
 724
 725	skb_reserve(skb, hlen);
 726
 727	skb_reset_network_header(skb);
 728	iph = ip_hdr(skb);
 729	skb_put(skb, sizeof(struct iphdr) + 4);
 730
 731	iph->version  = 4;
 732	iph->ihl      = (sizeof(struct iphdr)+4)>>2;
 733	iph->tos      = 0xc0;
 734	iph->frag_off = htons(IP_DF);
 735	iph->ttl      = 1;
 736	iph->daddr    = dst;
 737	iph->saddr    = fl4.saddr;
 738	iph->protocol = IPPROTO_IGMP;
 739	ip_select_ident(net, skb, NULL);
 740	((u8 *)&iph[1])[0] = IPOPT_RA;
 741	((u8 *)&iph[1])[1] = 4;
 742	((u8 *)&iph[1])[2] = 0;
 743	((u8 *)&iph[1])[3] = 0;
 744
 745	ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
 746	ih->type = type;
 747	ih->code = 0;
 748	ih->csum = 0;
 749	ih->group = group;
 750	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 751
 752	return ip_local_out(net, skb->sk, skb);
 753}
 754
 755static void igmp_gq_timer_expire(unsigned long data)
 756{
 757	struct in_device *in_dev = (struct in_device *)data;
 758
 759	in_dev->mr_gq_running = 0;
 760	igmpv3_send_report(in_dev, NULL);
 761	in_dev_put(in_dev);
 762}
 763
 764static void igmp_ifc_timer_expire(unsigned long data)
 765{
 766	struct in_device *in_dev = (struct in_device *)data;
 
 767
 768	igmpv3_send_cr(in_dev);
 769	if (in_dev->mr_ifc_count) {
 770		in_dev->mr_ifc_count--;
 
 
 
 
 
 
 771		igmp_ifc_start_timer(in_dev,
 772				     unsolicited_report_interval(in_dev));
 773	}
 774	in_dev_put(in_dev);
 775}
 776
 777static void igmp_ifc_event(struct in_device *in_dev)
 778{
 779	struct net *net = dev_net(in_dev->dev);
 780	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 781		return;
 782	in_dev->mr_ifc_count = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
 783	igmp_ifc_start_timer(in_dev, 1);
 784}
 785
 786
 787static void igmp_timer_expire(unsigned long data)
 788{
 789	struct ip_mc_list *im = (struct ip_mc_list *)data;
 790	struct in_device *in_dev = im->interface;
 791
 792	spin_lock(&im->lock);
 793	im->tm_running = 0;
 794
 795	if (im->unsolicit_count) {
 796		im->unsolicit_count--;
 797		igmp_start_timer(im, unsolicited_report_interval(in_dev));
 798	}
 799	im->reporter = 1;
 800	spin_unlock(&im->lock);
 801
 802	if (IGMP_V1_SEEN(in_dev))
 803		igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
 804	else if (IGMP_V2_SEEN(in_dev))
 805		igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
 806	else
 807		igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
 808
 809	ip_ma_put(im);
 810}
 811
 812/* mark EXCLUDE-mode sources */
 813static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 814{
 815	struct ip_sf_list *psf;
 816	int i, scount;
 817
 818	scount = 0;
 819	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 820		if (scount == nsrcs)
 821			break;
 822		for (i = 0; i < nsrcs; i++) {
 823			/* skip inactive filters */
 824			if (psf->sf_count[MCAST_INCLUDE] ||
 825			    pmc->sfcount[MCAST_EXCLUDE] !=
 826			    psf->sf_count[MCAST_EXCLUDE])
 827				break;
 828			if (srcs[i] == psf->sf_inaddr) {
 829				scount++;
 830				break;
 831			}
 832		}
 833	}
 834	pmc->gsquery = 0;
 835	if (scount == nsrcs)	/* all sources excluded */
 836		return 0;
 837	return 1;
 838}
 839
 840static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 841{
 842	struct ip_sf_list *psf;
 843	int i, scount;
 844
 845	if (pmc->sfmode == MCAST_EXCLUDE)
 846		return igmp_xmarksources(pmc, nsrcs, srcs);
 847
 848	/* mark INCLUDE-mode sources */
 849	scount = 0;
 850	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 851		if (scount == nsrcs)
 852			break;
 853		for (i = 0; i < nsrcs; i++)
 854			if (srcs[i] == psf->sf_inaddr) {
 855				psf->sf_gsresp = 1;
 856				scount++;
 857				break;
 858			}
 859	}
 860	if (!scount) {
 861		pmc->gsquery = 0;
 862		return 0;
 863	}
 864	pmc->gsquery = 1;
 865	return 1;
 866}
 867
 868/* return true if packet was dropped */
 869static bool igmp_heard_report(struct in_device *in_dev, __be32 group)
 870{
 871	struct ip_mc_list *im;
 872	struct net *net = dev_net(in_dev->dev);
 873
 874	/* Timers are only set for non-local groups */
 875
 876	if (group == IGMP_ALL_HOSTS)
 877		return false;
 878	if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
 
 879		return false;
 880
 881	rcu_read_lock();
 882	for_each_pmc_rcu(in_dev, im) {
 883		if (im->multiaddr == group) {
 884			igmp_stop_timer(im);
 885			break;
 886		}
 887	}
 888	rcu_read_unlock();
 889	return false;
 890}
 891
 892/* return true if packet was dropped */
 893static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
 894	int len)
 895{
 896	struct igmphdr 		*ih = igmp_hdr(skb);
 897	struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
 898	struct ip_mc_list	*im;
 899	__be32			group = ih->group;
 900	int			max_delay;
 901	int			mark = 0;
 902	struct net		*net = dev_net(in_dev->dev);
 903
 904
 905	if (len == 8) {
 906		if (ih->code == 0) {
 907			/* Alas, old v1 router presents here. */
 908
 909			max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 910			in_dev->mr_v1_seen = jiffies +
 911				IGMP_V1_ROUTER_PRESENT_TIMEOUT;
 
 912			group = 0;
 913		} else {
 914			/* v2 router present */
 915			max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
 916			in_dev->mr_v2_seen = jiffies +
 917				IGMP_V2_ROUTER_PRESENT_TIMEOUT;
 
 918		}
 919		/* cancel the interface change timer */
 920		in_dev->mr_ifc_count = 0;
 921		if (del_timer(&in_dev->mr_ifc_timer))
 922			__in_dev_put(in_dev);
 923		/* clear deleted report items */
 924		igmpv3_clear_delrec(in_dev);
 925	} else if (len < 12) {
 926		return true;	/* ignore bogus packet; freed by caller */
 927	} else if (IGMP_V1_SEEN(in_dev)) {
 928		/* This is a v3 query with v1 queriers present */
 929		max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 930		group = 0;
 931	} else if (IGMP_V2_SEEN(in_dev)) {
 932		/* this is a v3 query with v2 queriers present;
 933		 * Interpretation of the max_delay code is problematic here.
 934		 * A real v2 host would use ih_code directly, while v3 has a
 935		 * different encoding. We use the v3 encoding as more likely
 936		 * to be intended in a v3 query.
 937		 */
 938		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 939		if (!max_delay)
 940			max_delay = 1;	/* can't mod w/ 0 */
 941	} else { /* v3 */
 942		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
 943			return true;
 944
 945		ih3 = igmpv3_query_hdr(skb);
 946		if (ih3->nsrcs) {
 947			if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
 948					   + ntohs(ih3->nsrcs)*sizeof(__be32)))
 949				return true;
 950			ih3 = igmpv3_query_hdr(skb);
 951		}
 952
 953		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 954		if (!max_delay)
 955			max_delay = 1;	/* can't mod w/ 0 */
 956		in_dev->mr_maxdelay = max_delay;
 957		if (ih3->qrv)
 958			in_dev->mr_qrv = ih3->qrv;
 
 
 
 
 
 
 
 
 
 
 
 
 
 959		if (!group) { /* general query */
 960			if (ih3->nsrcs)
 961				return true;	/* no sources allowed */
 962			igmp_gq_start_timer(in_dev);
 963			return false;
 964		}
 965		/* mark sources to include, if group & source-specific */
 966		mark = ih3->nsrcs != 0;
 967	}
 968
 969	/*
 970	 * - Start the timers in all of our membership records
 971	 *   that the query applies to for the interface on
 972	 *   which the query arrived excl. those that belong
 973	 *   to a "local" group (224.0.0.X)
 974	 * - For timers already running check if they need to
 975	 *   be reset.
 976	 * - Use the igmp->igmp_code field as the maximum
 977	 *   delay possible
 978	 */
 979	rcu_read_lock();
 980	for_each_pmc_rcu(in_dev, im) {
 981		int changed;
 982
 983		if (group && group != im->multiaddr)
 984			continue;
 985		if (im->multiaddr == IGMP_ALL_HOSTS)
 986			continue;
 987		if (ipv4_is_local_multicast(im->multiaddr) &&
 988		    !net->ipv4.sysctl_igmp_llm_reports)
 989			continue;
 990		spin_lock_bh(&im->lock);
 991		if (im->tm_running)
 992			im->gsquery = im->gsquery && mark;
 993		else
 994			im->gsquery = mark;
 995		changed = !im->gsquery ||
 996			igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
 997		spin_unlock_bh(&im->lock);
 998		if (changed)
 999			igmp_mod_timer(im, max_delay);
1000	}
1001	rcu_read_unlock();
1002	return false;
1003}
1004
1005/* called in rcu_read_lock() section */
1006int igmp_rcv(struct sk_buff *skb)
1007{
1008	/* This basically follows the spec line by line -- see RFC1112 */
1009	struct igmphdr *ih;
1010	struct in_device *in_dev = __in_dev_get_rcu(skb->dev);
 
1011	int len = skb->len;
1012	bool dropped = true;
1013
 
 
 
 
 
 
 
1014	if (!in_dev)
1015		goto drop;
1016
1017	if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
1018		goto drop;
1019
1020	if (skb_checksum_simple_validate(skb))
1021		goto drop;
1022
1023	ih = igmp_hdr(skb);
1024	switch (ih->type) {
1025	case IGMP_HOST_MEMBERSHIP_QUERY:
1026		dropped = igmp_heard_query(in_dev, skb, len);
1027		break;
1028	case IGMP_HOST_MEMBERSHIP_REPORT:
1029	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1030		/* Is it our report looped back? */
1031		if (rt_is_output_route(skb_rtable(skb)))
1032			break;
1033		/* don't rely on MC router hearing unicast reports */
1034		if (skb->pkt_type == PACKET_MULTICAST ||
1035		    skb->pkt_type == PACKET_BROADCAST)
1036			dropped = igmp_heard_report(in_dev, ih->group);
1037		break;
1038	case IGMP_PIM:
1039#ifdef CONFIG_IP_PIMSM_V1
1040		return pim_rcv_v1(skb);
1041#endif
1042	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1043	case IGMP_DVMRP:
1044	case IGMP_TRACE:
1045	case IGMP_HOST_LEAVE_MESSAGE:
1046	case IGMP_MTRACE:
1047	case IGMP_MTRACE_RESP:
1048		break;
1049	default:
1050		break;
1051	}
1052
1053drop:
1054	if (dropped)
1055		kfree_skb(skb);
1056	else
1057		consume_skb(skb);
1058	return 0;
1059}
1060
1061#endif
1062
1063
1064/*
1065 *	Add a filter to a device
1066 */
1067
1068static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1069{
1070	char buf[MAX_ADDR_LEN];
1071	struct net_device *dev = in_dev->dev;
1072
1073	/* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1074	   We will get multicast token leakage, when IFF_MULTICAST
1075	   is changed. This check should be done in ndo_set_rx_mode
1076	   routine. Something sort of:
1077	   if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1078	   --ANK
1079	   */
1080	if (arp_mc_map(addr, buf, dev, 0) == 0)
1081		dev_mc_add(dev, buf);
1082}
1083
1084/*
1085 *	Remove a filter from a device
1086 */
1087
1088static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1089{
1090	char buf[MAX_ADDR_LEN];
1091	struct net_device *dev = in_dev->dev;
1092
1093	if (arp_mc_map(addr, buf, dev, 0) == 0)
1094		dev_mc_del(dev, buf);
1095}
1096
1097#ifdef CONFIG_IP_MULTICAST
1098/*
1099 * deleted ip_mc_list manipulation
1100 */
1101static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
 
1102{
1103	struct ip_mc_list *pmc;
1104	struct net *net = dev_net(in_dev->dev);
1105
1106	/* this is an "ip_mc_list" for convenience; only the fields below
1107	 * are actually used. In particular, the refcnt and users are not
1108	 * used for management of the delete list. Using the same structure
1109	 * for deleted items allows change reports to use common code with
1110	 * non-deleted or query-response MCA's.
1111	 */
1112	pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
1113	if (!pmc)
1114		return;
 
1115	spin_lock_bh(&im->lock);
1116	pmc->interface = im->interface;
1117	in_dev_hold(in_dev);
1118	pmc->multiaddr = im->multiaddr;
1119	pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1120	pmc->sfmode = im->sfmode;
1121	if (pmc->sfmode == MCAST_INCLUDE) {
1122		struct ip_sf_list *psf;
1123
1124		pmc->tomb = im->tomb;
1125		pmc->sources = im->sources;
1126		im->tomb = im->sources = NULL;
1127		for (psf = pmc->sources; psf; psf = psf->sf_next)
1128			psf->sf_crcount = pmc->crcount;
1129	}
1130	spin_unlock_bh(&im->lock);
1131
1132	spin_lock_bh(&in_dev->mc_tomb_lock);
1133	pmc->next = in_dev->mc_tomb;
1134	in_dev->mc_tomb = pmc;
1135	spin_unlock_bh(&in_dev->mc_tomb_lock);
1136}
1137
1138/*
1139 * restore ip_mc_list deleted records
1140 */
1141static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1142{
1143	struct ip_mc_list *pmc, *pmc_prev;
1144	struct ip_sf_list *psf;
1145	struct net *net = dev_net(in_dev->dev);
1146	__be32 multiaddr = im->multiaddr;
1147
1148	spin_lock_bh(&in_dev->mc_tomb_lock);
1149	pmc_prev = NULL;
1150	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) {
1151		if (pmc->multiaddr == multiaddr)
1152			break;
1153		pmc_prev = pmc;
1154	}
1155	if (pmc) {
1156		if (pmc_prev)
1157			pmc_prev->next = pmc->next;
1158		else
1159			in_dev->mc_tomb = pmc->next;
1160	}
1161	spin_unlock_bh(&in_dev->mc_tomb_lock);
1162
1163	spin_lock_bh(&im->lock);
1164	if (pmc) {
1165		im->interface = pmc->interface;
1166		im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1167		im->sfmode = pmc->sfmode;
1168		if (pmc->sfmode == MCAST_INCLUDE) {
1169			im->tomb = pmc->tomb;
1170			im->sources = pmc->sources;
1171			for (psf = im->sources; psf; psf = psf->sf_next)
1172				psf->sf_crcount = im->crcount;
 
 
 
 
1173		}
1174		in_dev_put(pmc->interface);
1175		kfree(pmc);
1176	}
1177	spin_unlock_bh(&im->lock);
1178}
1179
1180/*
1181 * flush ip_mc_list deleted records
1182 */
1183static void igmpv3_clear_delrec(struct in_device *in_dev)
1184{
1185	struct ip_mc_list *pmc, *nextpmc;
1186
1187	spin_lock_bh(&in_dev->mc_tomb_lock);
1188	pmc = in_dev->mc_tomb;
1189	in_dev->mc_tomb = NULL;
1190	spin_unlock_bh(&in_dev->mc_tomb_lock);
1191
1192	for (; pmc; pmc = nextpmc) {
1193		nextpmc = pmc->next;
1194		ip_mc_clear_src(pmc);
1195		in_dev_put(pmc->interface);
1196		kfree(pmc);
1197	}
1198	/* clear dead sources, too */
1199	rcu_read_lock();
1200	for_each_pmc_rcu(in_dev, pmc) {
1201		struct ip_sf_list *psf, *psf_next;
1202
1203		spin_lock_bh(&pmc->lock);
1204		psf = pmc->tomb;
1205		pmc->tomb = NULL;
1206		spin_unlock_bh(&pmc->lock);
1207		for (; psf; psf = psf_next) {
1208			psf_next = psf->sf_next;
1209			kfree(psf);
1210		}
1211	}
1212	rcu_read_unlock();
1213}
1214#endif
1215
1216static void igmp_group_dropped(struct ip_mc_list *im)
1217{
1218	struct in_device *in_dev = im->interface;
1219#ifdef CONFIG_IP_MULTICAST
1220	struct net *net = dev_net(in_dev->dev);
1221	int reporter;
1222#endif
1223
1224	if (im->loaded) {
1225		im->loaded = 0;
1226		ip_mc_filter_del(in_dev, im->multiaddr);
1227	}
1228
1229#ifdef CONFIG_IP_MULTICAST
1230	if (im->multiaddr == IGMP_ALL_HOSTS)
1231		return;
1232	if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
 
1233		return;
1234
1235	reporter = im->reporter;
1236	igmp_stop_timer(im);
1237
1238	if (!in_dev->dead) {
1239		if (IGMP_V1_SEEN(in_dev))
1240			return;
1241		if (IGMP_V2_SEEN(in_dev)) {
1242			if (reporter)
1243				igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1244			return;
1245		}
1246		/* IGMPv3 */
1247		igmpv3_add_delrec(in_dev, im);
1248
1249		igmp_ifc_event(in_dev);
1250	}
1251#endif
1252}
1253
 
 
 
 
 
1254static void igmp_group_added(struct ip_mc_list *im)
1255{
1256	struct in_device *in_dev = im->interface;
1257#ifdef CONFIG_IP_MULTICAST
1258	struct net *net = dev_net(in_dev->dev);
1259#endif
1260
1261	if (im->loaded == 0) {
1262		im->loaded = 1;
1263		ip_mc_filter_add(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	if (in_dev->dead)
1273		return;
 
 
1274	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1275		spin_lock_bh(&im->lock);
1276		igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY);
1277		spin_unlock_bh(&im->lock);
1278		return;
1279	}
1280	/* else, v3 */
1281
1282	im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
 
 
 
 
 
 
1283	igmp_ifc_event(in_dev);
1284#endif
1285}
1286
1287
1288/*
1289 *	Multicast list managers
1290 */
1291
1292static u32 ip_mc_hash(const struct ip_mc_list *im)
1293{
1294	return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
1295}
1296
1297static void ip_mc_hash_add(struct in_device *in_dev,
1298			   struct ip_mc_list *im)
1299{
1300	struct ip_mc_list __rcu **mc_hash;
1301	u32 hash;
1302
1303	mc_hash = rtnl_dereference(in_dev->mc_hash);
1304	if (mc_hash) {
1305		hash = ip_mc_hash(im);
1306		im->next_hash = mc_hash[hash];
1307		rcu_assign_pointer(mc_hash[hash], im);
1308		return;
1309	}
1310
1311	/* do not use a hash table for small number of items */
1312	if (in_dev->mc_count < 4)
1313		return;
1314
1315	mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
1316			  GFP_KERNEL);
1317	if (!mc_hash)
1318		return;
1319
1320	for_each_pmc_rtnl(in_dev, im) {
1321		hash = ip_mc_hash(im);
1322		im->next_hash = mc_hash[hash];
1323		RCU_INIT_POINTER(mc_hash[hash], im);
1324	}
1325
1326	rcu_assign_pointer(in_dev->mc_hash, mc_hash);
1327}
1328
1329static void ip_mc_hash_remove(struct in_device *in_dev,
1330			      struct ip_mc_list *im)
1331{
1332	struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
1333	struct ip_mc_list *aux;
1334
1335	if (!mc_hash)
1336		return;
1337	mc_hash += ip_mc_hash(im);
1338	while ((aux = rtnl_dereference(*mc_hash)) != im)
1339		mc_hash = &aux->next_hash;
1340	*mc_hash = im->next_hash;
1341}
1342
1343
1344/*
1345 *	A socket has joined a multicast group on device dev.
1346 */
1347
1348void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1349{
 
1350	struct ip_mc_list *im;
1351#ifdef CONFIG_IP_MULTICAST
1352	struct net *net = dev_net(in_dev->dev);
1353#endif
1354
1355	ASSERT_RTNL();
1356
1357	for_each_pmc_rtnl(in_dev, im) {
1358		if (im->multiaddr == addr) {
1359			im->users++;
1360			ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1361			goto out;
 
 
 
 
 
 
 
 
 
1362		}
1363	}
1364
1365	im = kzalloc(sizeof(*im), GFP_KERNEL);
 
 
 
 
 
 
1366	if (!im)
1367		goto out;
1368
1369	im->users = 1;
1370	im->interface = in_dev;
1371	in_dev_hold(in_dev);
1372	im->multiaddr = addr;
1373	/* initial mode is (EX, empty) */
1374	im->sfmode = MCAST_EXCLUDE;
1375	im->sfcount[MCAST_EXCLUDE] = 1;
1376	atomic_set(&im->refcnt, 1);
1377	spin_lock_init(&im->lock);
1378#ifdef CONFIG_IP_MULTICAST
1379	setup_timer(&im->timer, igmp_timer_expire, (unsigned long)im);
1380	im->unsolicit_count = net->ipv4.sysctl_igmp_qrv;
1381#endif
1382
1383	im->next_rcu = in_dev->mc_list;
1384	in_dev->mc_count++;
1385	rcu_assign_pointer(in_dev->mc_list, im);
1386
1387	ip_mc_hash_add(in_dev, im);
1388
1389#ifdef CONFIG_IP_MULTICAST
1390	igmpv3_del_delrec(in_dev, im);
1391#endif
1392	igmp_group_added(im);
1393	if (!in_dev->dead)
1394		ip_rt_multicast_event(in_dev);
1395out:
1396	return;
1397}
 
 
 
 
 
 
 
 
 
 
 
1398EXPORT_SYMBOL(ip_mc_inc_group);
1399
1400static int ip_mc_check_iphdr(struct sk_buff *skb)
1401{
1402	const struct iphdr *iph;
1403	unsigned int len;
1404	unsigned int offset = skb_network_offset(skb) + sizeof(*iph);
1405
1406	if (!pskb_may_pull(skb, offset))
1407		return -EINVAL;
1408
1409	iph = ip_hdr(skb);
1410
1411	if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph))
1412		return -EINVAL;
1413
1414	offset += ip_hdrlen(skb) - sizeof(*iph);
1415
1416	if (!pskb_may_pull(skb, offset))
1417		return -EINVAL;
1418
1419	iph = ip_hdr(skb);
1420
1421	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1422		return -EINVAL;
1423
1424	len = skb_network_offset(skb) + ntohs(iph->tot_len);
1425	if (skb->len < len || len < offset)
1426		return -EINVAL;
1427
1428	skb_set_transport_header(skb, offset);
1429
1430	return 0;
1431}
1432
1433static int ip_mc_check_igmp_reportv3(struct sk_buff *skb)
1434{
1435	unsigned int len = skb_transport_offset(skb);
1436
1437	len += sizeof(struct igmpv3_report);
1438
1439	return pskb_may_pull(skb, len) ? 0 : -EINVAL;
1440}
1441
1442static int ip_mc_check_igmp_query(struct sk_buff *skb)
1443{
1444	unsigned int len = skb_transport_offset(skb);
1445
1446	len += sizeof(struct igmphdr);
1447	if (skb->len < len)
1448		return -EINVAL;
1449
1450	/* IGMPv{1,2}? */
1451	if (skb->len != len) {
1452		/* or IGMPv3? */
1453		len += sizeof(struct igmpv3_query) - sizeof(struct igmphdr);
1454		if (skb->len < len || !pskb_may_pull(skb, len))
 
 
 
1455			return -EINVAL;
1456	}
1457
1458	/* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1459	 * all-systems destination addresses (224.0.0.1) for general queries
1460	 */
1461	if (!igmp_hdr(skb)->group &&
1462	    ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP))
1463		return -EINVAL;
1464
1465	return 0;
1466}
1467
1468static int ip_mc_check_igmp_msg(struct sk_buff *skb)
1469{
1470	switch (igmp_hdr(skb)->type) {
1471	case IGMP_HOST_LEAVE_MESSAGE:
1472	case IGMP_HOST_MEMBERSHIP_REPORT:
1473	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1474		/* fall through */
1475		return 0;
1476	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1477		return ip_mc_check_igmp_reportv3(skb);
1478	case IGMP_HOST_MEMBERSHIP_QUERY:
1479		return ip_mc_check_igmp_query(skb);
1480	default:
1481		return -ENOMSG;
1482	}
1483}
1484
1485static inline __sum16 ip_mc_validate_checksum(struct sk_buff *skb)
1486{
1487	return skb_checksum_simple_validate(skb);
1488}
1489
1490static int __ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
1491
1492{
 
 
1493	struct sk_buff *skb_chk;
1494	unsigned int transport_len;
1495	unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr);
1496	int ret = -EINVAL;
1497
1498	transport_len = ntohs(ip_hdr(skb)->tot_len) - ip_hdrlen(skb);
 
1499
1500	skb_chk = skb_checksum_trimmed(skb, transport_len,
1501				       ip_mc_validate_checksum);
1502	if (!skb_chk)
1503		goto err;
1504
1505	if (!pskb_may_pull(skb_chk, len))
1506		goto err;
1507
1508	ret = ip_mc_check_igmp_msg(skb_chk);
1509	if (ret)
1510		goto err;
1511
1512	if (skb_trimmed)
1513		*skb_trimmed = skb_chk;
1514	/* free now unneeded clone */
1515	else if (skb_chk != skb)
1516		kfree_skb(skb_chk);
1517
1518	ret = 0;
1519
1520err:
1521	if (ret && skb_chk && skb_chk != skb)
1522		kfree_skb(skb_chk);
1523
1524	return ret;
1525}
1526
1527/**
1528 * ip_mc_check_igmp - checks whether this is a sane IGMP packet
1529 * @skb: the skb to validate
1530 * @skb_trimmed: to store an skb pointer trimmed to IPv4 packet tail (optional)
1531 *
1532 * Checks whether an IPv4 packet is a valid IGMP packet. If so sets
1533 * skb transport header accordingly and returns zero.
1534 *
1535 * -EINVAL: A broken packet was detected, i.e. it violates some internet
1536 *  standard
1537 * -ENOMSG: IP header validation succeeded but it is not an IGMP packet.
1538 * -ENOMEM: A memory allocation failure happened.
1539 *
1540 * Optionally, an skb pointer might be provided via skb_trimmed (or set it
1541 * to NULL): After parsing an IGMP packet successfully it will point to
1542 * an skb which has its tail aligned to the IP packet end. This might
1543 * either be the originally provided skb or a trimmed, cloned version if
1544 * the skb frame had data beyond the IP packet. A cloned skb allows us
1545 * to leave the original skb and its full frame unchanged (which might be
1546 * desirable for layer 2 frame jugglers).
1547 *
1548 * Caller needs to set the skb network header and free any returned skb if it
1549 * differs from the provided skb.
1550 */
1551int ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
1552{
1553	int ret = ip_mc_check_iphdr(skb);
1554
1555	if (ret < 0)
1556		return ret;
1557
1558	if (ip_hdr(skb)->protocol != IPPROTO_IGMP)
1559		return -ENOMSG;
1560
1561	return __ip_mc_check_igmp(skb, skb_trimmed);
 
 
 
 
1562}
1563EXPORT_SYMBOL(ip_mc_check_igmp);
1564
1565/*
1566 *	Resend IGMP JOIN report; used by netdev notifier.
1567 */
1568static void ip_mc_rejoin_groups(struct in_device *in_dev)
1569{
1570#ifdef CONFIG_IP_MULTICAST
1571	struct ip_mc_list *im;
1572	int type;
1573	struct net *net = dev_net(in_dev->dev);
1574
1575	ASSERT_RTNL();
1576
1577	for_each_pmc_rtnl(in_dev, im) {
1578		if (im->multiaddr == IGMP_ALL_HOSTS)
1579			continue;
1580		if (ipv4_is_local_multicast(im->multiaddr) &&
1581		    !net->ipv4.sysctl_igmp_llm_reports)
1582			continue;
1583
1584		/* a failover is happening and switches
1585		 * must be notified immediately
1586		 */
1587		if (IGMP_V1_SEEN(in_dev))
1588			type = IGMP_HOST_MEMBERSHIP_REPORT;
1589		else if (IGMP_V2_SEEN(in_dev))
1590			type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1591		else
1592			type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1593		igmp_send_report(in_dev, im, type);
1594	}
1595#endif
1596}
1597
1598/*
1599 *	A socket has left a multicast group on device dev
1600 */
1601
1602void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
1603{
1604	struct ip_mc_list *i;
1605	struct ip_mc_list __rcu **ip;
1606
1607	ASSERT_RTNL();
1608
1609	for (ip = &in_dev->mc_list;
1610	     (i = rtnl_dereference(*ip)) != NULL;
1611	     ip = &i->next_rcu) {
1612		if (i->multiaddr == addr) {
1613			if (--i->users == 0) {
1614				ip_mc_hash_remove(in_dev, i);
1615				*ip = i->next_rcu;
1616				in_dev->mc_count--;
1617				igmp_group_dropped(i);
1618				ip_mc_clear_src(i);
1619
1620				if (!in_dev->dead)
1621					ip_rt_multicast_event(in_dev);
1622
1623				ip_ma_put(i);
1624				return;
1625			}
1626			break;
1627		}
1628	}
1629}
1630EXPORT_SYMBOL(ip_mc_dec_group);
1631
1632/* Device changing type */
1633
1634void ip_mc_unmap(struct in_device *in_dev)
1635{
1636	struct ip_mc_list *pmc;
1637
1638	ASSERT_RTNL();
1639
1640	for_each_pmc_rtnl(in_dev, pmc)
1641		igmp_group_dropped(pmc);
1642}
1643
1644void ip_mc_remap(struct in_device *in_dev)
1645{
1646	struct ip_mc_list *pmc;
1647
1648	ASSERT_RTNL();
1649
1650	for_each_pmc_rtnl(in_dev, pmc) {
1651#ifdef CONFIG_IP_MULTICAST
1652		igmpv3_del_delrec(in_dev, pmc);
1653#endif
1654		igmp_group_added(pmc);
1655	}
1656}
1657
1658/* Device going down */
1659
1660void ip_mc_down(struct in_device *in_dev)
1661{
1662	struct ip_mc_list *pmc;
1663
1664	ASSERT_RTNL();
1665
1666	for_each_pmc_rtnl(in_dev, pmc)
1667		igmp_group_dropped(pmc);
1668
1669#ifdef CONFIG_IP_MULTICAST
1670	in_dev->mr_ifc_count = 0;
1671	if (del_timer(&in_dev->mr_ifc_timer))
1672		__in_dev_put(in_dev);
1673	in_dev->mr_gq_running = 0;
1674	if (del_timer(&in_dev->mr_gq_timer))
1675		__in_dev_put(in_dev);
1676#endif
1677
1678	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1679}
1680
1681void ip_mc_init_dev(struct in_device *in_dev)
 
1682{
1683#ifdef CONFIG_IP_MULTICAST
1684	struct net *net = dev_net(in_dev->dev);
 
 
 
 
 
 
 
 
 
1685#endif
 
 
 
1686	ASSERT_RTNL();
1687
1688#ifdef CONFIG_IP_MULTICAST
1689	setup_timer(&in_dev->mr_gq_timer, igmp_gq_timer_expire,
1690			(unsigned long)in_dev);
1691	setup_timer(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire,
1692			(unsigned long)in_dev);
1693	in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1694#endif
 
1695
1696	spin_lock_init(&in_dev->mc_tomb_lock);
1697}
1698
1699/* Device going up */
1700
1701void ip_mc_up(struct in_device *in_dev)
1702{
1703	struct ip_mc_list *pmc;
1704#ifdef CONFIG_IP_MULTICAST
1705	struct net *net = dev_net(in_dev->dev);
1706#endif
1707
1708	ASSERT_RTNL();
1709
1710#ifdef CONFIG_IP_MULTICAST
1711	in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1712#endif
1713	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1714
1715	for_each_pmc_rtnl(in_dev, pmc) {
1716#ifdef CONFIG_IP_MULTICAST
1717		igmpv3_del_delrec(in_dev, pmc);
1718#endif
1719		igmp_group_added(pmc);
1720	}
1721}
1722
1723/*
1724 *	Device is about to be destroyed: clean up.
1725 */
1726
1727void ip_mc_destroy_dev(struct in_device *in_dev)
1728{
1729	struct ip_mc_list *i;
1730
1731	ASSERT_RTNL();
1732
1733	/* Deactivate timers */
1734	ip_mc_down(in_dev);
1735#ifdef CONFIG_IP_MULTICAST
1736	igmpv3_clear_delrec(in_dev);
1737#endif
1738
1739	while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1740		in_dev->mc_list = i->next_rcu;
1741		in_dev->mc_count--;
 
1742		ip_ma_put(i);
1743	}
1744}
1745
1746/* RTNL is locked */
1747static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1748{
1749	struct net_device *dev = NULL;
1750	struct in_device *idev = NULL;
1751
1752	if (imr->imr_ifindex) {
1753		idev = inetdev_by_index(net, imr->imr_ifindex);
1754		return idev;
1755	}
1756	if (imr->imr_address.s_addr) {
1757		dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1758		if (!dev)
1759			return NULL;
1760	}
1761
1762	if (!dev) {
1763		struct rtable *rt = ip_route_output(net,
1764						    imr->imr_multiaddr.s_addr,
1765						    0, 0, 0);
 
1766		if (!IS_ERR(rt)) {
1767			dev = rt->dst.dev;
1768			ip_rt_put(rt);
1769		}
1770	}
1771	if (dev) {
1772		imr->imr_ifindex = dev->ifindex;
1773		idev = __in_dev_get_rtnl(dev);
1774	}
1775	return idev;
1776}
1777
1778/*
1779 *	Join a socket to a group
1780 */
1781
1782static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1783	__be32 *psfsrc)
1784{
1785	struct ip_sf_list *psf, *psf_prev;
1786	int rv = 0;
1787
1788	psf_prev = NULL;
1789	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1790		if (psf->sf_inaddr == *psfsrc)
1791			break;
1792		psf_prev = psf;
1793	}
1794	if (!psf || psf->sf_count[sfmode] == 0) {
1795		/* source filter not found, or count wrong =>  bug */
1796		return -ESRCH;
1797	}
1798	psf->sf_count[sfmode]--;
1799	if (psf->sf_count[sfmode] == 0) {
1800		ip_rt_multicast_event(pmc->interface);
1801	}
1802	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1803#ifdef CONFIG_IP_MULTICAST
1804		struct in_device *in_dev = pmc->interface;
1805		struct net *net = dev_net(in_dev->dev);
1806#endif
1807
1808		/* no more filters for this source */
1809		if (psf_prev)
1810			psf_prev->sf_next = psf->sf_next;
1811		else
1812			pmc->sources = psf->sf_next;
1813#ifdef CONFIG_IP_MULTICAST
1814		if (psf->sf_oldin &&
1815		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1816			psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1817			psf->sf_next = pmc->tomb;
1818			pmc->tomb = psf;
1819			rv = 1;
1820		} else
1821#endif
1822			kfree(psf);
1823	}
1824	return rv;
1825}
1826
1827#ifndef CONFIG_IP_MULTICAST
1828#define igmp_ifc_event(x)	do { } while (0)
1829#endif
1830
1831static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1832			 int sfcount, __be32 *psfsrc, int delta)
1833{
1834	struct ip_mc_list *pmc;
1835	int	changerec = 0;
1836	int	i, err;
1837
1838	if (!in_dev)
1839		return -ENODEV;
1840	rcu_read_lock();
1841	for_each_pmc_rcu(in_dev, pmc) {
1842		if (*pmca == pmc->multiaddr)
1843			break;
1844	}
1845	if (!pmc) {
1846		/* MCA not found?? bug */
1847		rcu_read_unlock();
1848		return -ESRCH;
1849	}
1850	spin_lock_bh(&pmc->lock);
1851	rcu_read_unlock();
1852#ifdef CONFIG_IP_MULTICAST
1853	sf_markstate(pmc);
1854#endif
1855	if (!delta) {
1856		err = -EINVAL;
1857		if (!pmc->sfcount[sfmode])
1858			goto out_unlock;
1859		pmc->sfcount[sfmode]--;
1860	}
1861	err = 0;
1862	for (i = 0; i < sfcount; i++) {
1863		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1864
1865		changerec |= rv > 0;
1866		if (!err && rv < 0)
1867			err = rv;
1868	}
1869	if (pmc->sfmode == MCAST_EXCLUDE &&
1870	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1871	    pmc->sfcount[MCAST_INCLUDE]) {
1872#ifdef CONFIG_IP_MULTICAST
1873		struct ip_sf_list *psf;
1874		struct net *net = dev_net(in_dev->dev);
1875#endif
1876
1877		/* filter mode change */
1878		pmc->sfmode = MCAST_INCLUDE;
1879#ifdef CONFIG_IP_MULTICAST
1880		pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1881		in_dev->mr_ifc_count = pmc->crcount;
1882		for (psf = pmc->sources; psf; psf = psf->sf_next)
1883			psf->sf_crcount = 0;
1884		igmp_ifc_event(pmc->interface);
1885	} else if (sf_setstate(pmc) || changerec) {
1886		igmp_ifc_event(pmc->interface);
1887#endif
1888	}
1889out_unlock:
1890	spin_unlock_bh(&pmc->lock);
1891	return err;
1892}
1893
1894/*
1895 * Add multicast single-source filter to the interface list
1896 */
1897static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1898	__be32 *psfsrc)
1899{
1900	struct ip_sf_list *psf, *psf_prev;
1901
1902	psf_prev = NULL;
1903	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1904		if (psf->sf_inaddr == *psfsrc)
1905			break;
1906		psf_prev = psf;
1907	}
1908	if (!psf) {
1909		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1910		if (!psf)
1911			return -ENOBUFS;
1912		psf->sf_inaddr = *psfsrc;
1913		if (psf_prev) {
1914			psf_prev->sf_next = psf;
1915		} else
1916			pmc->sources = psf;
1917	}
1918	psf->sf_count[sfmode]++;
1919	if (psf->sf_count[sfmode] == 1) {
1920		ip_rt_multicast_event(pmc->interface);
1921	}
1922	return 0;
1923}
1924
1925#ifdef CONFIG_IP_MULTICAST
1926static void sf_markstate(struct ip_mc_list *pmc)
1927{
1928	struct ip_sf_list *psf;
1929	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1930
1931	for (psf = pmc->sources; psf; psf = psf->sf_next)
1932		if (pmc->sfcount[MCAST_EXCLUDE]) {
1933			psf->sf_oldin = mca_xcount ==
1934				psf->sf_count[MCAST_EXCLUDE] &&
1935				!psf->sf_count[MCAST_INCLUDE];
1936		} else
1937			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1938}
1939
1940static int sf_setstate(struct ip_mc_list *pmc)
1941{
1942	struct ip_sf_list *psf, *dpsf;
1943	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1944	int qrv = pmc->interface->mr_qrv;
1945	int new_in, rv;
1946
1947	rv = 0;
1948	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1949		if (pmc->sfcount[MCAST_EXCLUDE]) {
1950			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1951				!psf->sf_count[MCAST_INCLUDE];
1952		} else
1953			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1954		if (new_in) {
1955			if (!psf->sf_oldin) {
1956				struct ip_sf_list *prev = NULL;
1957
1958				for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) {
1959					if (dpsf->sf_inaddr == psf->sf_inaddr)
1960						break;
1961					prev = dpsf;
1962				}
1963				if (dpsf) {
1964					if (prev)
1965						prev->sf_next = dpsf->sf_next;
1966					else
1967						pmc->tomb = dpsf->sf_next;
1968					kfree(dpsf);
1969				}
1970				psf->sf_crcount = qrv;
1971				rv++;
1972			}
1973		} else if (psf->sf_oldin) {
1974
1975			psf->sf_crcount = 0;
1976			/*
1977			 * add or update "delete" records if an active filter
1978			 * is now inactive
1979			 */
1980			for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next)
1981				if (dpsf->sf_inaddr == psf->sf_inaddr)
1982					break;
1983			if (!dpsf) {
1984				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
1985				if (!dpsf)
1986					continue;
1987				*dpsf = *psf;
1988				/* pmc->lock held by callers */
1989				dpsf->sf_next = pmc->tomb;
1990				pmc->tomb = dpsf;
1991			}
1992			dpsf->sf_crcount = qrv;
1993			rv++;
1994		}
1995	}
1996	return rv;
1997}
1998#endif
1999
2000/*
2001 * Add multicast source filter list to the interface list
2002 */
2003static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
2004			 int sfcount, __be32 *psfsrc, int delta)
2005{
2006	struct ip_mc_list *pmc;
2007	int	isexclude;
2008	int	i, err;
2009
2010	if (!in_dev)
2011		return -ENODEV;
2012	rcu_read_lock();
2013	for_each_pmc_rcu(in_dev, pmc) {
2014		if (*pmca == pmc->multiaddr)
2015			break;
2016	}
2017	if (!pmc) {
2018		/* MCA not found?? bug */
2019		rcu_read_unlock();
2020		return -ESRCH;
2021	}
2022	spin_lock_bh(&pmc->lock);
2023	rcu_read_unlock();
2024
2025#ifdef CONFIG_IP_MULTICAST
2026	sf_markstate(pmc);
2027#endif
2028	isexclude = pmc->sfmode == MCAST_EXCLUDE;
2029	if (!delta)
2030		pmc->sfcount[sfmode]++;
2031	err = 0;
2032	for (i = 0; i < sfcount; i++) {
2033		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2034		if (err)
2035			break;
2036	}
2037	if (err) {
2038		int j;
2039
2040		if (!delta)
2041			pmc->sfcount[sfmode]--;
2042		for (j = 0; j < i; j++)
2043			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2044	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
2045#ifdef CONFIG_IP_MULTICAST
2046		struct ip_sf_list *psf;
2047		struct net *net = dev_net(pmc->interface->dev);
2048		in_dev = pmc->interface;
2049#endif
2050
2051		/* filter mode change */
2052		if (pmc->sfcount[MCAST_EXCLUDE])
2053			pmc->sfmode = MCAST_EXCLUDE;
2054		else if (pmc->sfcount[MCAST_INCLUDE])
2055			pmc->sfmode = MCAST_INCLUDE;
2056#ifdef CONFIG_IP_MULTICAST
2057		/* else no filters; keep old mode for reports */
2058
2059		pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
2060		in_dev->mr_ifc_count = pmc->crcount;
2061		for (psf = pmc->sources; psf; psf = psf->sf_next)
2062			psf->sf_crcount = 0;
2063		igmp_ifc_event(in_dev);
2064	} else if (sf_setstate(pmc)) {
2065		igmp_ifc_event(in_dev);
2066#endif
2067	}
2068	spin_unlock_bh(&pmc->lock);
2069	return err;
2070}
2071
2072static void ip_mc_clear_src(struct ip_mc_list *pmc)
2073{
2074	struct ip_sf_list *psf, *nextpsf;
2075
2076	for (psf = pmc->tomb; psf; psf = nextpsf) {
2077		nextpsf = psf->sf_next;
2078		kfree(psf);
2079	}
2080	pmc->tomb = NULL;
2081	for (psf = pmc->sources; psf; psf = nextpsf) {
2082		nextpsf = psf->sf_next;
2083		kfree(psf);
2084	}
2085	pmc->sources = NULL;
2086	pmc->sfmode = MCAST_EXCLUDE;
2087	pmc->sfcount[MCAST_INCLUDE] = 0;
2088	pmc->sfcount[MCAST_EXCLUDE] = 1;
 
 
 
 
2089}
2090
2091/* Join a multicast group
2092 */
2093
2094int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
2095{
2096	__be32 addr = imr->imr_multiaddr.s_addr;
2097	struct ip_mc_socklist *iml, *i;
2098	struct in_device *in_dev;
2099	struct inet_sock *inet = inet_sk(sk);
2100	struct net *net = sock_net(sk);
2101	int ifindex;
2102	int count = 0;
2103	int err;
2104
2105	ASSERT_RTNL();
2106
2107	if (!ipv4_is_multicast(addr))
2108		return -EINVAL;
2109
2110	in_dev = ip_mc_find_dev(net, imr);
2111
2112	if (!in_dev) {
2113		err = -ENODEV;
2114		goto done;
2115	}
2116
2117	err = -EADDRINUSE;
2118	ifindex = imr->imr_ifindex;
2119	for_each_pmc_rtnl(inet, i) {
2120		if (i->multi.imr_multiaddr.s_addr == addr &&
2121		    i->multi.imr_ifindex == ifindex)
2122			goto done;
2123		count++;
2124	}
2125	err = -ENOBUFS;
2126	if (count >= net->ipv4.sysctl_igmp_max_memberships)
2127		goto done;
2128	iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
2129	if (!iml)
2130		goto done;
2131
2132	memcpy(&iml->multi, imr, sizeof(*imr));
2133	iml->next_rcu = inet->mc_list;
2134	iml->sflist = NULL;
2135	iml->sfmode = MCAST_EXCLUDE;
2136	rcu_assign_pointer(inet->mc_list, iml);
2137	ip_mc_inc_group(in_dev, addr);
2138	err = 0;
2139done:
2140	return err;
2141}
 
 
 
 
 
 
 
2142EXPORT_SYMBOL(ip_mc_join_group);
2143
 
 
 
 
 
 
 
 
2144static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
2145			   struct in_device *in_dev)
2146{
2147	struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
2148	int err;
2149
2150	if (!psf) {
2151		/* any-source empty exclude case */
2152		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2153			iml->sfmode, 0, NULL, 0);
2154	}
2155	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2156			iml->sfmode, psf->sl_count, psf->sl_addr, 0);
2157	RCU_INIT_POINTER(iml->sflist, NULL);
2158	/* decrease mem now to avoid the memleak warning */
2159	atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc);
2160	kfree_rcu(psf, rcu);
2161	return err;
2162}
2163
2164int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
2165{
2166	struct inet_sock *inet = inet_sk(sk);
2167	struct ip_mc_socklist *iml;
2168	struct ip_mc_socklist __rcu **imlp;
2169	struct in_device *in_dev;
2170	struct net *net = sock_net(sk);
2171	__be32 group = imr->imr_multiaddr.s_addr;
2172	u32 ifindex;
2173	int ret = -EADDRNOTAVAIL;
2174
2175	ASSERT_RTNL();
2176
2177	in_dev = ip_mc_find_dev(net, imr);
2178	if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) {
2179		ret = -ENODEV;
2180		goto out;
2181	}
2182	ifindex = imr->imr_ifindex;
2183	for (imlp = &inet->mc_list;
2184	     (iml = rtnl_dereference(*imlp)) != NULL;
2185	     imlp = &iml->next_rcu) {
2186		if (iml->multi.imr_multiaddr.s_addr != group)
2187			continue;
2188		if (ifindex) {
2189			if (iml->multi.imr_ifindex != ifindex)
2190				continue;
2191		} else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
2192				iml->multi.imr_address.s_addr)
2193			continue;
2194
2195		(void) ip_mc_leave_src(sk, iml, in_dev);
2196
2197		*imlp = iml->next_rcu;
2198
2199		if (in_dev)
2200			ip_mc_dec_group(in_dev, group);
2201
2202		/* decrease mem now to avoid the memleak warning */
2203		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2204		kfree_rcu(iml, rcu);
2205		return 0;
2206	}
2207out:
2208	return ret;
2209}
2210EXPORT_SYMBOL(ip_mc_leave_group);
2211
2212int ip_mc_source(int add, int omode, struct sock *sk, struct
2213	ip_mreq_source *mreqs, int ifindex)
2214{
2215	int err;
2216	struct ip_mreqn imr;
2217	__be32 addr = mreqs->imr_multiaddr;
2218	struct ip_mc_socklist *pmc;
2219	struct in_device *in_dev = NULL;
2220	struct inet_sock *inet = inet_sk(sk);
2221	struct ip_sf_socklist *psl;
2222	struct net *net = sock_net(sk);
2223	int leavegroup = 0;
2224	int i, j, rv;
2225
2226	if (!ipv4_is_multicast(addr))
2227		return -EINVAL;
2228
2229	ASSERT_RTNL();
2230
2231	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
2232	imr.imr_address.s_addr = mreqs->imr_interface;
2233	imr.imr_ifindex = ifindex;
2234	in_dev = ip_mc_find_dev(net, &imr);
2235
2236	if (!in_dev) {
2237		err = -ENODEV;
2238		goto done;
2239	}
2240	err = -EADDRNOTAVAIL;
2241
2242	for_each_pmc_rtnl(inet, pmc) {
2243		if ((pmc->multi.imr_multiaddr.s_addr ==
2244		     imr.imr_multiaddr.s_addr) &&
2245		    (pmc->multi.imr_ifindex == imr.imr_ifindex))
2246			break;
2247	}
2248	if (!pmc) {		/* must have a prior join */
2249		err = -EINVAL;
2250		goto done;
2251	}
2252	/* if a source filter was set, must be the same mode as before */
2253	if (pmc->sflist) {
2254		if (pmc->sfmode != omode) {
2255			err = -EINVAL;
2256			goto done;
2257		}
2258	} else if (pmc->sfmode != omode) {
2259		/* allow mode switches for empty-set filters */
2260		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
2261		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
2262			NULL, 0);
2263		pmc->sfmode = omode;
2264	}
2265
2266	psl = rtnl_dereference(pmc->sflist);
2267	if (!add) {
2268		if (!psl)
2269			goto done;	/* err = -EADDRNOTAVAIL */
2270		rv = !0;
2271		for (i = 0; i < psl->sl_count; i++) {
2272			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2273				sizeof(__be32));
2274			if (rv == 0)
2275				break;
2276		}
2277		if (rv)		/* source not found */
2278			goto done;	/* err = -EADDRNOTAVAIL */
2279
2280		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2281		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
2282			leavegroup = 1;
2283			goto done;
2284		}
2285
2286		/* update the interface filter */
2287		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2288			&mreqs->imr_sourceaddr, 1);
2289
2290		for (j = i+1; j < psl->sl_count; j++)
2291			psl->sl_addr[j-1] = psl->sl_addr[j];
2292		psl->sl_count--;
2293		err = 0;
2294		goto done;
2295	}
2296	/* else, add a new source to the filter */
2297
2298	if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) {
2299		err = -ENOBUFS;
2300		goto done;
2301	}
2302	if (!psl || psl->sl_count == psl->sl_max) {
2303		struct ip_sf_socklist *newpsl;
2304		int count = IP_SFBLOCK;
2305
2306		if (psl)
2307			count += psl->sl_max;
2308		newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
 
2309		if (!newpsl) {
2310			err = -ENOBUFS;
2311			goto done;
2312		}
2313		newpsl->sl_max = count;
2314		newpsl->sl_count = count - IP_SFBLOCK;
2315		if (psl) {
2316			for (i = 0; i < psl->sl_count; i++)
2317				newpsl->sl_addr[i] = psl->sl_addr[i];
2318			/* decrease mem now to avoid the memleak warning */
2319			atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2320			kfree_rcu(psl, rcu);
2321		}
2322		rcu_assign_pointer(pmc->sflist, newpsl);
 
 
2323		psl = newpsl;
2324	}
2325	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
2326	for (i = 0; i < psl->sl_count; i++) {
2327		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2328			sizeof(__be32));
2329		if (rv == 0)
2330			break;
2331	}
2332	if (rv == 0)		/* address already there is an error */
2333		goto done;
2334	for (j = psl->sl_count-1; j >= i; j--)
2335		psl->sl_addr[j+1] = psl->sl_addr[j];
2336	psl->sl_addr[i] = mreqs->imr_sourceaddr;
2337	psl->sl_count++;
2338	err = 0;
2339	/* update the interface list */
2340	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2341		&mreqs->imr_sourceaddr, 1);
2342done:
2343	if (leavegroup)
2344		err = ip_mc_leave_group(sk, &imr);
2345	return err;
2346}
2347
2348int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2349{
2350	int err = 0;
2351	struct ip_mreqn	imr;
2352	__be32 addr = msf->imsf_multiaddr;
2353	struct ip_mc_socklist *pmc;
2354	struct in_device *in_dev;
2355	struct inet_sock *inet = inet_sk(sk);
2356	struct ip_sf_socklist *newpsl, *psl;
2357	struct net *net = sock_net(sk);
2358	int leavegroup = 0;
2359
2360	if (!ipv4_is_multicast(addr))
2361		return -EINVAL;
2362	if (msf->imsf_fmode != MCAST_INCLUDE &&
2363	    msf->imsf_fmode != MCAST_EXCLUDE)
2364		return -EINVAL;
2365
2366	ASSERT_RTNL();
2367
2368	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2369	imr.imr_address.s_addr = msf->imsf_interface;
2370	imr.imr_ifindex = ifindex;
2371	in_dev = ip_mc_find_dev(net, &imr);
2372
2373	if (!in_dev) {
2374		err = -ENODEV;
2375		goto done;
2376	}
2377
2378	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2379	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2380		leavegroup = 1;
2381		goto done;
2382	}
2383
2384	for_each_pmc_rtnl(inet, pmc) {
2385		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2386		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2387			break;
2388	}
2389	if (!pmc) {		/* must have a prior join */
2390		err = -EINVAL;
2391		goto done;
2392	}
2393	if (msf->imsf_numsrc) {
2394		newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2395							   GFP_KERNEL);
 
2396		if (!newpsl) {
2397			err = -ENOBUFS;
2398			goto done;
2399		}
2400		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2401		memcpy(newpsl->sl_addr, msf->imsf_slist,
2402			msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2403		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2404			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2405		if (err) {
2406			sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
 
 
2407			goto done;
2408		}
2409	} else {
2410		newpsl = NULL;
2411		(void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2412				     msf->imsf_fmode, 0, NULL, 0);
2413	}
2414	psl = rtnl_dereference(pmc->sflist);
2415	if (psl) {
2416		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2417			psl->sl_count, psl->sl_addr, 0);
2418		/* decrease mem now to avoid the memleak warning */
2419		atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2420		kfree_rcu(psl, rcu);
2421	} else
2422		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2423			0, NULL, 0);
 
2424	rcu_assign_pointer(pmc->sflist, newpsl);
 
 
2425	pmc->sfmode = msf->imsf_fmode;
2426	err = 0;
2427done:
2428	if (leavegroup)
2429		err = ip_mc_leave_group(sk, &imr);
2430	return err;
2431}
2432
2433int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2434	struct ip_msfilter __user *optval, int __user *optlen)
2435{
2436	int err, len, count, copycount;
2437	struct ip_mreqn	imr;
2438	__be32 addr = msf->imsf_multiaddr;
2439	struct ip_mc_socklist *pmc;
2440	struct in_device *in_dev;
2441	struct inet_sock *inet = inet_sk(sk);
2442	struct ip_sf_socklist *psl;
2443	struct net *net = sock_net(sk);
2444
2445	ASSERT_RTNL();
2446
2447	if (!ipv4_is_multicast(addr))
2448		return -EINVAL;
2449
2450	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2451	imr.imr_address.s_addr = msf->imsf_interface;
2452	imr.imr_ifindex = 0;
2453	in_dev = ip_mc_find_dev(net, &imr);
2454
2455	if (!in_dev) {
2456		err = -ENODEV;
2457		goto done;
2458	}
2459	err = -EADDRNOTAVAIL;
2460
2461	for_each_pmc_rtnl(inet, pmc) {
2462		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2463		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2464			break;
2465	}
2466	if (!pmc)		/* must have a prior join */
2467		goto done;
2468	msf->imsf_fmode = pmc->sfmode;
2469	psl = rtnl_dereference(pmc->sflist);
2470	if (!psl) {
2471		len = 0;
2472		count = 0;
2473	} else {
2474		count = psl->sl_count;
2475	}
2476	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2477	len = copycount * sizeof(psl->sl_addr[0]);
2478	msf->imsf_numsrc = count;
2479	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2480	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
 
2481		return -EFAULT;
2482	}
2483	if (len &&
2484	    copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
 
 
2485		return -EFAULT;
2486	return 0;
2487done:
2488	return err;
2489}
2490
2491int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2492	struct group_filter __user *optval, int __user *optlen)
2493{
2494	int err, i, count, copycount;
2495	struct sockaddr_in *psin;
2496	__be32 addr;
2497	struct ip_mc_socklist *pmc;
2498	struct inet_sock *inet = inet_sk(sk);
2499	struct ip_sf_socklist *psl;
2500
2501	ASSERT_RTNL();
2502
2503	psin = (struct sockaddr_in *)&gsf->gf_group;
2504	if (psin->sin_family != AF_INET)
2505		return -EINVAL;
2506	addr = psin->sin_addr.s_addr;
2507	if (!ipv4_is_multicast(addr))
2508		return -EINVAL;
2509
2510	err = -EADDRNOTAVAIL;
2511
2512	for_each_pmc_rtnl(inet, pmc) {
2513		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2514		    pmc->multi.imr_ifindex == gsf->gf_interface)
2515			break;
2516	}
2517	if (!pmc)		/* must have a prior join */
2518		goto done;
2519	gsf->gf_fmode = pmc->sfmode;
2520	psl = rtnl_dereference(pmc->sflist);
2521	count = psl ? psl->sl_count : 0;
2522	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2523	gsf->gf_numsrc = count;
2524	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2525	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2526		return -EFAULT;
2527	}
2528	for (i = 0; i < copycount; i++) {
2529		struct sockaddr_storage ss;
2530
2531		psin = (struct sockaddr_in *)&ss;
2532		memset(&ss, 0, sizeof(ss));
2533		psin->sin_family = AF_INET;
2534		psin->sin_addr.s_addr = psl->sl_addr[i];
2535		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
 
2536			return -EFAULT;
 
2537	}
2538	return 0;
2539done:
2540	return err;
2541}
2542
2543/*
2544 * check if a multicast source filter allows delivery for a given <src,dst,intf>
2545 */
2546int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif)
 
2547{
2548	struct inet_sock *inet = inet_sk(sk);
2549	struct ip_mc_socklist *pmc;
2550	struct ip_sf_socklist *psl;
2551	int i;
2552	int ret;
2553
2554	ret = 1;
2555	if (!ipv4_is_multicast(loc_addr))
2556		goto out;
2557
2558	rcu_read_lock();
2559	for_each_pmc_rcu(inet, pmc) {
2560		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2561		    pmc->multi.imr_ifindex == dif)
 
2562			break;
2563	}
2564	ret = inet->mc_all;
2565	if (!pmc)
2566		goto unlock;
2567	psl = rcu_dereference(pmc->sflist);
2568	ret = (pmc->sfmode == MCAST_EXCLUDE);
2569	if (!psl)
2570		goto unlock;
2571
2572	for (i = 0; i < psl->sl_count; i++) {
2573		if (psl->sl_addr[i] == rmt_addr)
2574			break;
2575	}
2576	ret = 0;
2577	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2578		goto unlock;
2579	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2580		goto unlock;
2581	ret = 1;
2582unlock:
2583	rcu_read_unlock();
2584out:
2585	return ret;
2586}
2587
2588/*
2589 *	A socket is closing.
2590 */
2591
2592void ip_mc_drop_socket(struct sock *sk)
2593{
2594	struct inet_sock *inet = inet_sk(sk);
2595	struct ip_mc_socklist *iml;
2596	struct net *net = sock_net(sk);
2597
2598	if (!inet->mc_list)
2599		return;
2600
2601	rtnl_lock();
2602	while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2603		struct in_device *in_dev;
2604
2605		inet->mc_list = iml->next_rcu;
2606		in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2607		(void) ip_mc_leave_src(sk, iml, in_dev);
2608		if (in_dev)
2609			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2610		/* decrease mem now to avoid the memleak warning */
2611		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2612		kfree_rcu(iml, rcu);
2613	}
2614	rtnl_unlock();
2615}
2616
2617/* called with rcu_read_lock() */
2618int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto)
2619{
2620	struct ip_mc_list *im;
2621	struct ip_mc_list __rcu **mc_hash;
2622	struct ip_sf_list *psf;
2623	int rv = 0;
2624
2625	mc_hash = rcu_dereference(in_dev->mc_hash);
2626	if (mc_hash) {
2627		u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
2628
2629		for (im = rcu_dereference(mc_hash[hash]);
2630		     im != NULL;
2631		     im = rcu_dereference(im->next_hash)) {
2632			if (im->multiaddr == mc_addr)
2633				break;
2634		}
2635	} else {
2636		for_each_pmc_rcu(in_dev, im) {
2637			if (im->multiaddr == mc_addr)
2638				break;
2639		}
2640	}
2641	if (im && proto == IPPROTO_IGMP) {
2642		rv = 1;
2643	} else if (im) {
2644		if (src_addr) {
 
2645			for (psf = im->sources; psf; psf = psf->sf_next) {
2646				if (psf->sf_inaddr == src_addr)
2647					break;
2648			}
2649			if (psf)
2650				rv = psf->sf_count[MCAST_INCLUDE] ||
2651					psf->sf_count[MCAST_EXCLUDE] !=
2652					im->sfcount[MCAST_EXCLUDE];
2653			else
2654				rv = im->sfcount[MCAST_EXCLUDE] != 0;
 
2655		} else
2656			rv = 1; /* unspecified source; tentatively allow */
2657	}
2658	return rv;
2659}
2660
2661#if defined(CONFIG_PROC_FS)
2662struct igmp_mc_iter_state {
2663	struct seq_net_private p;
2664	struct net_device *dev;
2665	struct in_device *in_dev;
2666};
2667
2668#define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2669
2670static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2671{
2672	struct net *net = seq_file_net(seq);
2673	struct ip_mc_list *im = NULL;
2674	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2675
2676	state->in_dev = NULL;
2677	for_each_netdev_rcu(net, state->dev) {
2678		struct in_device *in_dev;
2679
2680		in_dev = __in_dev_get_rcu(state->dev);
2681		if (!in_dev)
2682			continue;
2683		im = rcu_dereference(in_dev->mc_list);
2684		if (im) {
2685			state->in_dev = in_dev;
2686			break;
2687		}
2688	}
2689	return im;
2690}
2691
2692static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2693{
2694	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2695
2696	im = rcu_dereference(im->next_rcu);
2697	while (!im) {
2698		state->dev = next_net_device_rcu(state->dev);
2699		if (!state->dev) {
2700			state->in_dev = NULL;
2701			break;
2702		}
2703		state->in_dev = __in_dev_get_rcu(state->dev);
2704		if (!state->in_dev)
2705			continue;
2706		im = rcu_dereference(state->in_dev->mc_list);
2707	}
2708	return im;
2709}
2710
2711static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2712{
2713	struct ip_mc_list *im = igmp_mc_get_first(seq);
2714	if (im)
2715		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2716			--pos;
2717	return pos ? NULL : im;
2718}
2719
2720static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2721	__acquires(rcu)
2722{
2723	rcu_read_lock();
2724	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2725}
2726
2727static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2728{
2729	struct ip_mc_list *im;
2730	if (v == SEQ_START_TOKEN)
2731		im = igmp_mc_get_first(seq);
2732	else
2733		im = igmp_mc_get_next(seq, v);
2734	++*pos;
2735	return im;
2736}
2737
2738static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2739	__releases(rcu)
2740{
2741	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2742
2743	state->in_dev = NULL;
2744	state->dev = NULL;
2745	rcu_read_unlock();
2746}
2747
2748static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2749{
2750	if (v == SEQ_START_TOKEN)
2751		seq_puts(seq,
2752			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2753	else {
2754		struct ip_mc_list *im = (struct ip_mc_list *)v;
2755		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2756		char   *querier;
2757		long delta;
2758
2759#ifdef CONFIG_IP_MULTICAST
2760		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2761			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2762			  "V3";
2763#else
2764		querier = "NONE";
2765#endif
2766
2767		if (rcu_access_pointer(state->in_dev->mc_list) == im) {
2768			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2769				   state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2770		}
2771
2772		delta = im->timer.expires - jiffies;
2773		seq_printf(seq,
2774			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2775			   im->multiaddr, im->users,
2776			   im->tm_running,
2777			   im->tm_running ? jiffies_delta_to_clock_t(delta) : 0,
2778			   im->reporter);
2779	}
2780	return 0;
2781}
2782
2783static const struct seq_operations igmp_mc_seq_ops = {
2784	.start	=	igmp_mc_seq_start,
2785	.next	=	igmp_mc_seq_next,
2786	.stop	=	igmp_mc_seq_stop,
2787	.show	=	igmp_mc_seq_show,
2788};
2789
2790static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2791{
2792	return seq_open_net(inode, file, &igmp_mc_seq_ops,
2793			sizeof(struct igmp_mc_iter_state));
2794}
2795
2796static const struct file_operations igmp_mc_seq_fops = {
2797	.owner		=	THIS_MODULE,
2798	.open		=	igmp_mc_seq_open,
2799	.read		=	seq_read,
2800	.llseek		=	seq_lseek,
2801	.release	=	seq_release_net,
2802};
2803
2804struct igmp_mcf_iter_state {
2805	struct seq_net_private p;
2806	struct net_device *dev;
2807	struct in_device *idev;
2808	struct ip_mc_list *im;
2809};
2810
2811#define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2812
2813static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2814{
2815	struct net *net = seq_file_net(seq);
2816	struct ip_sf_list *psf = NULL;
2817	struct ip_mc_list *im = NULL;
2818	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2819
2820	state->idev = NULL;
2821	state->im = NULL;
2822	for_each_netdev_rcu(net, state->dev) {
2823		struct in_device *idev;
2824		idev = __in_dev_get_rcu(state->dev);
2825		if (unlikely(!idev))
2826			continue;
2827		im = rcu_dereference(idev->mc_list);
2828		if (likely(im)) {
2829			spin_lock_bh(&im->lock);
2830			psf = im->sources;
2831			if (likely(psf)) {
2832				state->im = im;
2833				state->idev = idev;
2834				break;
2835			}
2836			spin_unlock_bh(&im->lock);
2837		}
2838	}
2839	return psf;
2840}
2841
2842static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2843{
2844	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2845
2846	psf = psf->sf_next;
2847	while (!psf) {
2848		spin_unlock_bh(&state->im->lock);
2849		state->im = state->im->next;
2850		while (!state->im) {
2851			state->dev = next_net_device_rcu(state->dev);
2852			if (!state->dev) {
2853				state->idev = NULL;
2854				goto out;
2855			}
2856			state->idev = __in_dev_get_rcu(state->dev);
2857			if (!state->idev)
2858				continue;
2859			state->im = rcu_dereference(state->idev->mc_list);
2860		}
2861		if (!state->im)
2862			break;
2863		spin_lock_bh(&state->im->lock);
2864		psf = state->im->sources;
2865	}
2866out:
2867	return psf;
2868}
2869
2870static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2871{
2872	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2873	if (psf)
2874		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2875			--pos;
2876	return pos ? NULL : psf;
2877}
2878
2879static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2880	__acquires(rcu)
2881{
2882	rcu_read_lock();
2883	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2884}
2885
2886static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2887{
2888	struct ip_sf_list *psf;
2889	if (v == SEQ_START_TOKEN)
2890		psf = igmp_mcf_get_first(seq);
2891	else
2892		psf = igmp_mcf_get_next(seq, v);
2893	++*pos;
2894	return psf;
2895}
2896
2897static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2898	__releases(rcu)
2899{
2900	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2901	if (likely(state->im)) {
2902		spin_unlock_bh(&state->im->lock);
2903		state->im = NULL;
2904	}
2905	state->idev = NULL;
2906	state->dev = NULL;
2907	rcu_read_unlock();
2908}
2909
2910static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2911{
2912	struct ip_sf_list *psf = (struct ip_sf_list *)v;
2913	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2914
2915	if (v == SEQ_START_TOKEN) {
2916		seq_puts(seq, "Idx Device        MCA        SRC    INC    EXC\n");
2917	} else {
2918		seq_printf(seq,
2919			   "%3d %6.6s 0x%08x "
2920			   "0x%08x %6lu %6lu\n",
2921			   state->dev->ifindex, state->dev->name,
2922			   ntohl(state->im->multiaddr),
2923			   ntohl(psf->sf_inaddr),
2924			   psf->sf_count[MCAST_INCLUDE],
2925			   psf->sf_count[MCAST_EXCLUDE]);
2926	}
2927	return 0;
2928}
2929
2930static const struct seq_operations igmp_mcf_seq_ops = {
2931	.start	=	igmp_mcf_seq_start,
2932	.next	=	igmp_mcf_seq_next,
2933	.stop	=	igmp_mcf_seq_stop,
2934	.show	=	igmp_mcf_seq_show,
2935};
2936
2937static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2938{
2939	return seq_open_net(inode, file, &igmp_mcf_seq_ops,
2940			sizeof(struct igmp_mcf_iter_state));
2941}
2942
2943static const struct file_operations igmp_mcf_seq_fops = {
2944	.owner		=	THIS_MODULE,
2945	.open		=	igmp_mcf_seq_open,
2946	.read		=	seq_read,
2947	.llseek		=	seq_lseek,
2948	.release	=	seq_release_net,
2949};
2950
2951static int __net_init igmp_net_init(struct net *net)
2952{
2953	struct proc_dir_entry *pde;
2954	int err;
2955
2956	pde = proc_create("igmp", S_IRUGO, net->proc_net, &igmp_mc_seq_fops);
 
2957	if (!pde)
2958		goto out_igmp;
2959	pde = proc_create("mcfilter", S_IRUGO, net->proc_net,
2960			  &igmp_mcf_seq_fops);
2961	if (!pde)
2962		goto out_mcfilter;
2963	err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET,
2964				   SOCK_DGRAM, 0, net);
2965	if (err < 0) {
2966		pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n",
2967		       err);
2968		goto out_sock;
2969	}
2970
2971	/* Sysctl initialization */
2972	net->ipv4.sysctl_igmp_max_memberships = 20;
2973	net->ipv4.sysctl_igmp_max_msf = 10;
2974	/* IGMP reports for link-local multicast groups are enabled by default */
2975	net->ipv4.sysctl_igmp_llm_reports = 1;
2976	net->ipv4.sysctl_igmp_qrv = 2;
2977	return 0;
2978
2979out_sock:
2980	remove_proc_entry("mcfilter", net->proc_net);
2981out_mcfilter:
2982	remove_proc_entry("igmp", net->proc_net);
2983out_igmp:
2984	return -ENOMEM;
2985}
2986
2987static void __net_exit igmp_net_exit(struct net *net)
2988{
2989	remove_proc_entry("mcfilter", net->proc_net);
2990	remove_proc_entry("igmp", net->proc_net);
2991	inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk);
2992}
2993
2994static struct pernet_operations igmp_net_ops = {
2995	.init = igmp_net_init,
2996	.exit = igmp_net_exit,
2997};
2998#endif
2999
3000static int igmp_netdev_event(struct notifier_block *this,
3001			     unsigned long event, void *ptr)
3002{
3003	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3004	struct in_device *in_dev;
3005
3006	switch (event) {
3007	case NETDEV_RESEND_IGMP:
3008		in_dev = __in_dev_get_rtnl(dev);
3009		if (in_dev)
3010			ip_mc_rejoin_groups(in_dev);
3011		break;
3012	default:
3013		break;
3014	}
3015	return NOTIFY_DONE;
3016}
3017
3018static struct notifier_block igmp_notifier = {
3019	.notifier_call = igmp_netdev_event,
3020};
3021
3022int __init igmp_mc_init(void)
3023{
3024#if defined(CONFIG_PROC_FS)
3025	int err;
3026
3027	err = register_pernet_subsys(&igmp_net_ops);
3028	if (err)
3029		return err;
3030	err = register_netdevice_notifier(&igmp_notifier);
3031	if (err)
3032		goto reg_notif_fail;
3033	return 0;
3034
3035reg_notif_fail:
3036	unregister_pernet_subsys(&igmp_net_ops);
3037	return err;
3038#else
3039	return register_netdevice_notifier(&igmp_notifier);
3040#endif
3041}