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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}
v6.2
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *	Linux NET3:	Internet Group Management Protocol  [IGMP]
   4 *
   5 *	This code implements the IGMP protocol as defined in RFC1112. There has
   6 *	been a further revision of this protocol since which is now supported.
   7 *
   8 *	If you have trouble with this module be careful what gcc you have used,
   9 *	the older version didn't come out right using gcc 2.5.8, the newer one
  10 *	seems to fall out with gcc 2.6.2.
  11 *
  12 *	Authors:
  13 *		Alan Cox <alan@lxorguk.ukuu.org.uk>
  14 *
  15 *	Fixes:
  16 *
  17 *		Alan Cox	:	Added lots of __inline__ to optimise
  18 *					the memory usage of all the tiny little
  19 *					functions.
  20 *		Alan Cox	:	Dumped the header building experiment.
  21 *		Alan Cox	:	Minor tweaks ready for multicast routing
  22 *					and extended IGMP protocol.
  23 *		Alan Cox	:	Removed a load of inline directives. Gcc 2.5.8
  24 *					writes utterly bogus code otherwise (sigh)
  25 *					fixed IGMP loopback to behave in the manner
  26 *					desired by mrouted, fixed the fact it has been
  27 *					broken since 1.3.6 and cleaned up a few minor
  28 *					points.
  29 *
  30 *		Chih-Jen Chang	:	Tried to revise IGMP to Version 2
  31 *		Tsu-Sheng Tsao		E-mail: chihjenc@scf.usc.edu and tsusheng@scf.usc.edu
  32 *					The enhancements are mainly based on Steve Deering's
  33 * 					ipmulti-3.5 source code.
  34 *		Chih-Jen Chang	:	Added the igmp_get_mrouter_info and
  35 *		Tsu-Sheng Tsao		igmp_set_mrouter_info to keep track of
  36 *					the mrouted version on that device.
  37 *		Chih-Jen Chang	:	Added the max_resp_time parameter to
  38 *		Tsu-Sheng Tsao		igmp_heard_query(). Using this parameter
  39 *					to identify the multicast router version
  40 *					and do what the IGMP version 2 specified.
  41 *		Chih-Jen Chang	:	Added a timer to revert to IGMP V2 router
  42 *		Tsu-Sheng Tsao		if the specified time expired.
  43 *		Alan Cox	:	Stop IGMP from 0.0.0.0 being accepted.
  44 *		Alan Cox	:	Use GFP_ATOMIC in the right places.
  45 *		Christian Daudt :	igmp timer wasn't set for local group
  46 *					memberships but was being deleted,
  47 *					which caused a "del_timer() called
  48 *					from %p with timer not initialized\n"
  49 *					message (960131).
  50 *		Christian Daudt :	removed del_timer from
  51 *					igmp_timer_expire function (960205).
  52 *             Christian Daudt :       igmp_heard_report now only calls
  53 *                                     igmp_timer_expire if tm->running is
  54 *                                     true (960216).
  55 *		Malcolm Beattie :	ttl comparison wrong in igmp_rcv made
  56 *					igmp_heard_query never trigger. Expiry
  57 *					miscalculation fixed in igmp_heard_query
  58 *					and random() made to return unsigned to
  59 *					prevent negative expiry times.
  60 *		Alexey Kuznetsov:	Wrong group leaving behaviour, backport
  61 *					fix from pending 2.1.x patches.
  62 *		Alan Cox:		Forget to enable FDDI support earlier.
  63 *		Alexey Kuznetsov:	Fixed leaving groups on device down.
  64 *		Alexey Kuznetsov:	Accordance to igmp-v2-06 draft.
  65 *		David L Stevens:	IGMPv3 support, with help from
  66 *					Vinay Kulkarni
  67 */
  68
  69#include <linux/module.h>
  70#include <linux/slab.h>
  71#include <linux/uaccess.h>
  72#include <linux/types.h>
  73#include <linux/kernel.h>
  74#include <linux/jiffies.h>
  75#include <linux/string.h>
  76#include <linux/socket.h>
  77#include <linux/sockios.h>
  78#include <linux/in.h>
  79#include <linux/inet.h>
  80#include <linux/netdevice.h>
  81#include <linux/skbuff.h>
  82#include <linux/inetdevice.h>
  83#include <linux/igmp.h>
  84#include <linux/if_arp.h>
  85#include <linux/rtnetlink.h>
  86#include <linux/times.h>
  87#include <linux/pkt_sched.h>
  88#include <linux/byteorder/generic.h>
  89
  90#include <net/net_namespace.h>
  91#include <net/arp.h>
  92#include <net/ip.h>
  93#include <net/protocol.h>
  94#include <net/route.h>
  95#include <net/sock.h>
  96#include <net/checksum.h>
  97#include <net/inet_common.h>
  98#include <linux/netfilter_ipv4.h>
  99#ifdef CONFIG_IP_MROUTE
 100#include <linux/mroute.h>
 101#endif
 102#ifdef CONFIG_PROC_FS
 103#include <linux/proc_fs.h>
 104#include <linux/seq_file.h>
 105#endif
 106
 107#ifdef CONFIG_IP_MULTICAST
 108/* Parameter names and values are taken from igmp-v2-06 draft */
 109
 110#define IGMP_QUERY_INTERVAL			(125*HZ)
 111#define IGMP_QUERY_RESPONSE_INTERVAL		(10*HZ)
 112
 113#define IGMP_INITIAL_REPORT_DELAY		(1)
 114
 115/* IGMP_INITIAL_REPORT_DELAY is not from IGMP specs!
 116 * IGMP specs require to report membership immediately after
 117 * joining a group, but we delay the first report by a
 118 * small interval. It seems more natural and still does not
 119 * contradict to specs provided this delay is small enough.
 120 */
 121
 122#define IGMP_V1_SEEN(in_dev) \
 123	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \
 124	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \
 125	 ((in_dev)->mr_v1_seen && \
 126	  time_before(jiffies, (in_dev)->mr_v1_seen)))
 127#define IGMP_V2_SEEN(in_dev) \
 128	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \
 129	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \
 130	 ((in_dev)->mr_v2_seen && \
 131	  time_before(jiffies, (in_dev)->mr_v2_seen)))
 132
 133static int unsolicited_report_interval(struct in_device *in_dev)
 134{
 135	int interval_ms, interval_jiffies;
 136
 137	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 138		interval_ms = IN_DEV_CONF_GET(
 139			in_dev,
 140			IGMPV2_UNSOLICITED_REPORT_INTERVAL);
 141	else /* v3 */
 142		interval_ms = IN_DEV_CONF_GET(
 143			in_dev,
 144			IGMPV3_UNSOLICITED_REPORT_INTERVAL);
 145
 146	interval_jiffies = msecs_to_jiffies(interval_ms);
 147
 148	/* _timer functions can't handle a delay of 0 jiffies so ensure
 149	 *  we always return a positive value.
 150	 */
 151	if (interval_jiffies <= 0)
 152		interval_jiffies = 1;
 153	return interval_jiffies;
 154}
 155
 156static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im,
 157			      gfp_t gfp);
 158static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im);
 159static void igmpv3_clear_delrec(struct in_device *in_dev);
 160static int sf_setstate(struct ip_mc_list *pmc);
 161static void sf_markstate(struct ip_mc_list *pmc);
 162#endif
 163static void ip_mc_clear_src(struct ip_mc_list *pmc);
 164static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
 165			 int sfcount, __be32 *psfsrc, int delta);
 166
 167static void ip_ma_put(struct ip_mc_list *im)
 168{
 169	if (refcount_dec_and_test(&im->refcnt)) {
 170		in_dev_put(im->interface);
 171		kfree_rcu(im, rcu);
 172	}
 173}
 174
 175#define for_each_pmc_rcu(in_dev, pmc)				\
 176	for (pmc = rcu_dereference(in_dev->mc_list);		\
 177	     pmc != NULL;					\
 178	     pmc = rcu_dereference(pmc->next_rcu))
 179
 180#define for_each_pmc_rtnl(in_dev, pmc)				\
 181	for (pmc = rtnl_dereference(in_dev->mc_list);		\
 182	     pmc != NULL;					\
 183	     pmc = rtnl_dereference(pmc->next_rcu))
 184
 185static void ip_sf_list_clear_all(struct ip_sf_list *psf)
 186{
 187	struct ip_sf_list *next;
 188
 189	while (psf) {
 190		next = psf->sf_next;
 191		kfree(psf);
 192		psf = next;
 193	}
 194}
 195
 196#ifdef CONFIG_IP_MULTICAST
 197
 198/*
 199 *	Timer management
 200 */
 201
 202static void igmp_stop_timer(struct ip_mc_list *im)
 203{
 204	spin_lock_bh(&im->lock);
 205	if (del_timer(&im->timer))
 206		refcount_dec(&im->refcnt);
 207	im->tm_running = 0;
 208	im->reporter = 0;
 209	im->unsolicit_count = 0;
 210	spin_unlock_bh(&im->lock);
 211}
 212
 213/* It must be called with locked im->lock */
 214static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
 215{
 216	int tv = get_random_u32_below(max_delay);
 217
 218	im->tm_running = 1;
 219	if (!mod_timer(&im->timer, jiffies+tv+2))
 220		refcount_inc(&im->refcnt);
 
 
 221}
 222
 223static void igmp_gq_start_timer(struct in_device *in_dev)
 224{
 225	int tv = get_random_u32_below(in_dev->mr_maxdelay);
 226	unsigned long exp = jiffies + tv + 2;
 227
 228	if (in_dev->mr_gq_running &&
 229	    time_after_eq(exp, (in_dev->mr_gq_timer).expires))
 230		return;
 231
 232	in_dev->mr_gq_running = 1;
 233	if (!mod_timer(&in_dev->mr_gq_timer, exp))
 234		in_dev_hold(in_dev);
 235}
 236
 237static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
 238{
 239	int tv = get_random_u32_below(delay);
 240
 241	if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
 242		in_dev_hold(in_dev);
 243}
 244
 245static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
 246{
 247	spin_lock_bh(&im->lock);
 248	im->unsolicit_count = 0;
 249	if (del_timer(&im->timer)) {
 250		if ((long)(im->timer.expires-jiffies) < max_delay) {
 251			add_timer(&im->timer);
 252			im->tm_running = 1;
 253			spin_unlock_bh(&im->lock);
 254			return;
 255		}
 256		refcount_dec(&im->refcnt);
 257	}
 258	igmp_start_timer(im, max_delay);
 259	spin_unlock_bh(&im->lock);
 260}
 261
 262
 263/*
 264 *	Send an IGMP report.
 265 */
 266
 267#define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
 268
 269
 270static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
 271	int gdeleted, int sdeleted)
 272{
 273	switch (type) {
 274	case IGMPV3_MODE_IS_INCLUDE:
 275	case IGMPV3_MODE_IS_EXCLUDE:
 276		if (gdeleted || sdeleted)
 277			return 0;
 278		if (!(pmc->gsquery && !psf->sf_gsresp)) {
 279			if (pmc->sfmode == MCAST_INCLUDE)
 280				return 1;
 281			/* don't include if this source is excluded
 282			 * in all filters
 283			 */
 284			if (psf->sf_count[MCAST_INCLUDE])
 285				return type == IGMPV3_MODE_IS_INCLUDE;
 286			return pmc->sfcount[MCAST_EXCLUDE] ==
 287				psf->sf_count[MCAST_EXCLUDE];
 288		}
 289		return 0;
 290	case IGMPV3_CHANGE_TO_INCLUDE:
 291		if (gdeleted || sdeleted)
 292			return 0;
 293		return psf->sf_count[MCAST_INCLUDE] != 0;
 294	case IGMPV3_CHANGE_TO_EXCLUDE:
 295		if (gdeleted || sdeleted)
 296			return 0;
 297		if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
 298		    psf->sf_count[MCAST_INCLUDE])
 299			return 0;
 300		return pmc->sfcount[MCAST_EXCLUDE] ==
 301			psf->sf_count[MCAST_EXCLUDE];
 302	case IGMPV3_ALLOW_NEW_SOURCES:
 303		if (gdeleted || !psf->sf_crcount)
 304			return 0;
 305		return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
 306	case IGMPV3_BLOCK_OLD_SOURCES:
 307		if (pmc->sfmode == MCAST_INCLUDE)
 308			return gdeleted || (psf->sf_crcount && sdeleted);
 309		return psf->sf_crcount && !gdeleted && !sdeleted;
 310	}
 311	return 0;
 312}
 313
 314static int
 315igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
 316{
 317	struct ip_sf_list *psf;
 318	int scount = 0;
 319
 320	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 321		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
 322			continue;
 323		scount++;
 324	}
 325	return scount;
 326}
 327
 328/* source address selection per RFC 3376 section 4.2.13 */
 329static __be32 igmpv3_get_srcaddr(struct net_device *dev,
 330				 const struct flowi4 *fl4)
 331{
 332	struct in_device *in_dev = __in_dev_get_rcu(dev);
 333	const struct in_ifaddr *ifa;
 334
 335	if (!in_dev)
 336		return htonl(INADDR_ANY);
 337
 338	in_dev_for_each_ifa_rcu(ifa, in_dev) {
 339		if (fl4->saddr == ifa->ifa_local)
 340			return fl4->saddr;
 341	}
 342
 343	return htonl(INADDR_ANY);
 344}
 345
 346static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
 347{
 348	struct sk_buff *skb;
 349	struct rtable *rt;
 350	struct iphdr *pip;
 351	struct igmpv3_report *pig;
 352	struct net *net = dev_net(dev);
 353	struct flowi4 fl4;
 354	int hlen = LL_RESERVED_SPACE(dev);
 355	int tlen = dev->needed_tailroom;
 356	unsigned int size = mtu;
 357
 
 358	while (1) {
 359		skb = alloc_skb(size + hlen + tlen,
 360				GFP_ATOMIC | __GFP_NOWARN);
 361		if (skb)
 362			break;
 363		size >>= 1;
 364		if (size < 256)
 365			return NULL;
 366	}
 367	skb->priority = TC_PRIO_CONTROL;
 368
 369	rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0,
 370				   0, 0,
 371				   IPPROTO_IGMP, 0, dev->ifindex);
 372	if (IS_ERR(rt)) {
 373		kfree_skb(skb);
 374		return NULL;
 375	}
 376
 377	skb_dst_set(skb, &rt->dst);
 378	skb->dev = dev;
 379
 380	skb_reserve(skb, hlen);
 381	skb_tailroom_reserve(skb, mtu, tlen);
 382
 383	skb_reset_network_header(skb);
 384	pip = ip_hdr(skb);
 385	skb_put(skb, sizeof(struct iphdr) + 4);
 386
 387	pip->version  = 4;
 388	pip->ihl      = (sizeof(struct iphdr)+4)>>2;
 389	pip->tos      = 0xc0;
 390	pip->frag_off = htons(IP_DF);
 391	pip->ttl      = 1;
 392	pip->daddr    = fl4.daddr;
 393
 394	rcu_read_lock();
 395	pip->saddr    = igmpv3_get_srcaddr(dev, &fl4);
 396	rcu_read_unlock();
 397
 398	pip->protocol = IPPROTO_IGMP;
 399	pip->tot_len  = 0;	/* filled in later */
 400	ip_select_ident(net, skb, NULL);
 401	((u8 *)&pip[1])[0] = IPOPT_RA;
 402	((u8 *)&pip[1])[1] = 4;
 403	((u8 *)&pip[1])[2] = 0;
 404	((u8 *)&pip[1])[3] = 0;
 405
 406	skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
 407	skb_put(skb, sizeof(*pig));
 408	pig = igmpv3_report_hdr(skb);
 409	pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
 410	pig->resv1 = 0;
 411	pig->csum = 0;
 412	pig->resv2 = 0;
 413	pig->ngrec = 0;
 414	return skb;
 415}
 416
 417static int igmpv3_sendpack(struct sk_buff *skb)
 418{
 419	struct igmphdr *pig = igmp_hdr(skb);
 420	const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
 421
 422	pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
 423
 424	return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
 425}
 426
 427static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
 428{
 429	return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
 430}
 431
 432static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
 433	int type, struct igmpv3_grec **ppgr, unsigned int mtu)
 434{
 435	struct net_device *dev = pmc->interface->dev;
 436	struct igmpv3_report *pih;
 437	struct igmpv3_grec *pgr;
 438
 439	if (!skb) {
 440		skb = igmpv3_newpack(dev, mtu);
 441		if (!skb)
 442			return NULL;
 443	}
 444	pgr = skb_put(skb, sizeof(struct igmpv3_grec));
 445	pgr->grec_type = type;
 446	pgr->grec_auxwords = 0;
 447	pgr->grec_nsrcs = 0;
 448	pgr->grec_mca = pmc->multiaddr;
 449	pih = igmpv3_report_hdr(skb);
 450	pih->ngrec = htons(ntohs(pih->ngrec)+1);
 451	*ppgr = pgr;
 452	return skb;
 453}
 454
 455#define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
 456
 457static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
 458	int type, int gdeleted, int sdeleted)
 459{
 460	struct net_device *dev = pmc->interface->dev;
 461	struct net *net = dev_net(dev);
 462	struct igmpv3_report *pih;
 463	struct igmpv3_grec *pgr = NULL;
 464	struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
 465	int scount, stotal, first, isquery, truncate;
 466	unsigned int mtu;
 467
 468	if (pmc->multiaddr == IGMP_ALL_HOSTS)
 469		return skb;
 470	if (ipv4_is_local_multicast(pmc->multiaddr) &&
 471	    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
 472		return skb;
 473
 474	mtu = READ_ONCE(dev->mtu);
 475	if (mtu < IPV4_MIN_MTU)
 476		return skb;
 477
 478	isquery = type == IGMPV3_MODE_IS_INCLUDE ||
 479		  type == IGMPV3_MODE_IS_EXCLUDE;
 480	truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
 481		    type == IGMPV3_CHANGE_TO_EXCLUDE;
 482
 483	stotal = scount = 0;
 484
 485	psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
 486
 487	if (!*psf_list)
 488		goto empty_source;
 489
 490	pih = skb ? igmpv3_report_hdr(skb) : NULL;
 491
 492	/* EX and TO_EX get a fresh packet, if needed */
 493	if (truncate) {
 494		if (pih && pih->ngrec &&
 495		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
 496			if (skb)
 497				igmpv3_sendpack(skb);
 498			skb = igmpv3_newpack(dev, mtu);
 499		}
 500	}
 501	first = 1;
 502	psf_prev = NULL;
 503	for (psf = *psf_list; psf; psf = psf_next) {
 504		__be32 *psrc;
 505
 506		psf_next = psf->sf_next;
 507
 508		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
 509			psf_prev = psf;
 510			continue;
 511		}
 512
 513		/* Based on RFC3376 5.1. Should not send source-list change
 514		 * records when there is a filter mode change.
 515		 */
 516		if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) ||
 517		     (!gdeleted && pmc->crcount)) &&
 518		    (type == IGMPV3_ALLOW_NEW_SOURCES ||
 519		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount)
 520			goto decrease_sf_crcount;
 521
 522		/* clear marks on query responses */
 523		if (isquery)
 524			psf->sf_gsresp = 0;
 525
 526		if (AVAILABLE(skb) < sizeof(__be32) +
 527		    first*sizeof(struct igmpv3_grec)) {
 528			if (truncate && !first)
 529				break;	 /* truncate these */
 530			if (pgr)
 531				pgr->grec_nsrcs = htons(scount);
 532			if (skb)
 533				igmpv3_sendpack(skb);
 534			skb = igmpv3_newpack(dev, mtu);
 535			first = 1;
 536			scount = 0;
 537		}
 538		if (first) {
 539			skb = add_grhead(skb, pmc, type, &pgr, mtu);
 540			first = 0;
 541		}
 542		if (!skb)
 543			return NULL;
 544		psrc = skb_put(skb, sizeof(__be32));
 545		*psrc = psf->sf_inaddr;
 546		scount++; stotal++;
 547		if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
 548		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
 549decrease_sf_crcount:
 550			psf->sf_crcount--;
 551			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
 552				if (psf_prev)
 553					psf_prev->sf_next = psf->sf_next;
 554				else
 555					*psf_list = psf->sf_next;
 556				kfree(psf);
 557				continue;
 558			}
 559		}
 560		psf_prev = psf;
 561	}
 562
 563empty_source:
 564	if (!stotal) {
 565		if (type == IGMPV3_ALLOW_NEW_SOURCES ||
 566		    type == IGMPV3_BLOCK_OLD_SOURCES)
 567			return skb;
 568		if (pmc->crcount || isquery) {
 569			/* make sure we have room for group header */
 570			if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) {
 571				igmpv3_sendpack(skb);
 572				skb = NULL; /* add_grhead will get a new one */
 573			}
 574			skb = add_grhead(skb, pmc, type, &pgr, mtu);
 575		}
 576	}
 577	if (pgr)
 578		pgr->grec_nsrcs = htons(scount);
 579
 580	if (isquery)
 581		pmc->gsquery = 0;	/* clear query state on report */
 582	return skb;
 583}
 584
 585static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
 586{
 587	struct sk_buff *skb = NULL;
 588	struct net *net = dev_net(in_dev->dev);
 589	int type;
 590
 591	if (!pmc) {
 592		rcu_read_lock();
 593		for_each_pmc_rcu(in_dev, pmc) {
 594			if (pmc->multiaddr == IGMP_ALL_HOSTS)
 595				continue;
 596			if (ipv4_is_local_multicast(pmc->multiaddr) &&
 597			    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
 598				continue;
 599			spin_lock_bh(&pmc->lock);
 600			if (pmc->sfcount[MCAST_EXCLUDE])
 601				type = IGMPV3_MODE_IS_EXCLUDE;
 602			else
 603				type = IGMPV3_MODE_IS_INCLUDE;
 604			skb = add_grec(skb, pmc, type, 0, 0);
 605			spin_unlock_bh(&pmc->lock);
 606		}
 607		rcu_read_unlock();
 608	} else {
 609		spin_lock_bh(&pmc->lock);
 610		if (pmc->sfcount[MCAST_EXCLUDE])
 611			type = IGMPV3_MODE_IS_EXCLUDE;
 612		else
 613			type = IGMPV3_MODE_IS_INCLUDE;
 614		skb = add_grec(skb, pmc, type, 0, 0);
 615		spin_unlock_bh(&pmc->lock);
 616	}
 617	if (!skb)
 618		return 0;
 619	return igmpv3_sendpack(skb);
 620}
 621
 622/*
 623 * remove zero-count source records from a source filter list
 624 */
 625static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
 626{
 627	struct ip_sf_list *psf_prev, *psf_next, *psf;
 628
 629	psf_prev = NULL;
 630	for (psf = *ppsf; psf; psf = psf_next) {
 631		psf_next = psf->sf_next;
 632		if (psf->sf_crcount == 0) {
 633			if (psf_prev)
 634				psf_prev->sf_next = psf->sf_next;
 635			else
 636				*ppsf = psf->sf_next;
 637			kfree(psf);
 638		} else
 639			psf_prev = psf;
 640	}
 641}
 642
 643static void kfree_pmc(struct ip_mc_list *pmc)
 644{
 645	ip_sf_list_clear_all(pmc->sources);
 646	ip_sf_list_clear_all(pmc->tomb);
 647	kfree(pmc);
 648}
 649
 650static void igmpv3_send_cr(struct in_device *in_dev)
 651{
 652	struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
 653	struct sk_buff *skb = NULL;
 654	int type, dtype;
 655
 656	rcu_read_lock();
 657	spin_lock_bh(&in_dev->mc_tomb_lock);
 658
 659	/* deleted MCA's */
 660	pmc_prev = NULL;
 661	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) {
 662		pmc_next = pmc->next;
 663		if (pmc->sfmode == MCAST_INCLUDE) {
 664			type = IGMPV3_BLOCK_OLD_SOURCES;
 665			dtype = IGMPV3_BLOCK_OLD_SOURCES;
 666			skb = add_grec(skb, pmc, type, 1, 0);
 667			skb = add_grec(skb, pmc, dtype, 1, 1);
 668		}
 669		if (pmc->crcount) {
 670			if (pmc->sfmode == MCAST_EXCLUDE) {
 671				type = IGMPV3_CHANGE_TO_INCLUDE;
 672				skb = add_grec(skb, pmc, type, 1, 0);
 673			}
 674			pmc->crcount--;
 675			if (pmc->crcount == 0) {
 676				igmpv3_clear_zeros(&pmc->tomb);
 677				igmpv3_clear_zeros(&pmc->sources);
 678			}
 679		}
 680		if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
 681			if (pmc_prev)
 682				pmc_prev->next = pmc_next;
 683			else
 684				in_dev->mc_tomb = pmc_next;
 685			in_dev_put(pmc->interface);
 686			kfree_pmc(pmc);
 687		} else
 688			pmc_prev = pmc;
 689	}
 690	spin_unlock_bh(&in_dev->mc_tomb_lock);
 691
 692	/* change recs */
 693	for_each_pmc_rcu(in_dev, pmc) {
 694		spin_lock_bh(&pmc->lock);
 695		if (pmc->sfcount[MCAST_EXCLUDE]) {
 696			type = IGMPV3_BLOCK_OLD_SOURCES;
 697			dtype = IGMPV3_ALLOW_NEW_SOURCES;
 698		} else {
 699			type = IGMPV3_ALLOW_NEW_SOURCES;
 700			dtype = IGMPV3_BLOCK_OLD_SOURCES;
 701		}
 702		skb = add_grec(skb, pmc, type, 0, 0);
 703		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
 704
 705		/* filter mode changes */
 706		if (pmc->crcount) {
 707			if (pmc->sfmode == MCAST_EXCLUDE)
 708				type = IGMPV3_CHANGE_TO_EXCLUDE;
 709			else
 710				type = IGMPV3_CHANGE_TO_INCLUDE;
 711			skb = add_grec(skb, pmc, type, 0, 0);
 712			pmc->crcount--;
 713		}
 714		spin_unlock_bh(&pmc->lock);
 715	}
 716	rcu_read_unlock();
 717
 718	if (!skb)
 719		return;
 720	(void) igmpv3_sendpack(skb);
 721}
 722
 723static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
 724	int type)
 725{
 726	struct sk_buff *skb;
 727	struct iphdr *iph;
 728	struct igmphdr *ih;
 729	struct rtable *rt;
 730	struct net_device *dev = in_dev->dev;
 731	struct net *net = dev_net(dev);
 732	__be32	group = pmc ? pmc->multiaddr : 0;
 733	struct flowi4 fl4;
 734	__be32	dst;
 735	int hlen, tlen;
 736
 737	if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
 738		return igmpv3_send_report(in_dev, pmc);
 739
 740	if (ipv4_is_local_multicast(group) &&
 741	    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
 742		return 0;
 743
 744	if (type == IGMP_HOST_LEAVE_MESSAGE)
 745		dst = IGMP_ALL_ROUTER;
 746	else
 747		dst = group;
 748
 749	rt = ip_route_output_ports(net, &fl4, NULL, dst, 0,
 750				   0, 0,
 751				   IPPROTO_IGMP, 0, dev->ifindex);
 752	if (IS_ERR(rt))
 753		return -1;
 754
 755	hlen = LL_RESERVED_SPACE(dev);
 756	tlen = dev->needed_tailroom;
 757	skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC);
 758	if (!skb) {
 759		ip_rt_put(rt);
 760		return -1;
 761	}
 762	skb->priority = TC_PRIO_CONTROL;
 763
 764	skb_dst_set(skb, &rt->dst);
 765
 766	skb_reserve(skb, hlen);
 767
 768	skb_reset_network_header(skb);
 769	iph = ip_hdr(skb);
 770	skb_put(skb, sizeof(struct iphdr) + 4);
 771
 772	iph->version  = 4;
 773	iph->ihl      = (sizeof(struct iphdr)+4)>>2;
 774	iph->tos      = 0xc0;
 775	iph->frag_off = htons(IP_DF);
 776	iph->ttl      = 1;
 777	iph->daddr    = dst;
 778	iph->saddr    = fl4.saddr;
 779	iph->protocol = IPPROTO_IGMP;
 780	ip_select_ident(net, skb, NULL);
 781	((u8 *)&iph[1])[0] = IPOPT_RA;
 782	((u8 *)&iph[1])[1] = 4;
 783	((u8 *)&iph[1])[2] = 0;
 784	((u8 *)&iph[1])[3] = 0;
 785
 786	ih = skb_put(skb, sizeof(struct igmphdr));
 787	ih->type = type;
 788	ih->code = 0;
 789	ih->csum = 0;
 790	ih->group = group;
 791	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 792
 793	return ip_local_out(net, skb->sk, skb);
 794}
 795
 796static void igmp_gq_timer_expire(struct timer_list *t)
 797{
 798	struct in_device *in_dev = from_timer(in_dev, t, mr_gq_timer);
 799
 800	in_dev->mr_gq_running = 0;
 801	igmpv3_send_report(in_dev, NULL);
 802	in_dev_put(in_dev);
 803}
 804
 805static void igmp_ifc_timer_expire(struct timer_list *t)
 806{
 807	struct in_device *in_dev = from_timer(in_dev, t, mr_ifc_timer);
 808	u32 mr_ifc_count;
 809
 810	igmpv3_send_cr(in_dev);
 811restart:
 812	mr_ifc_count = READ_ONCE(in_dev->mr_ifc_count);
 813
 814	if (mr_ifc_count) {
 815		if (cmpxchg(&in_dev->mr_ifc_count,
 816			    mr_ifc_count,
 817			    mr_ifc_count - 1) != mr_ifc_count)
 818			goto restart;
 819		igmp_ifc_start_timer(in_dev,
 820				     unsolicited_report_interval(in_dev));
 821	}
 822	in_dev_put(in_dev);
 823}
 824
 825static void igmp_ifc_event(struct in_device *in_dev)
 826{
 827	struct net *net = dev_net(in_dev->dev);
 828	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 829		return;
 830	WRITE_ONCE(in_dev->mr_ifc_count, in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv));
 831	igmp_ifc_start_timer(in_dev, 1);
 832}
 833
 834
 835static void igmp_timer_expire(struct timer_list *t)
 836{
 837	struct ip_mc_list *im = from_timer(im, t, timer);
 838	struct in_device *in_dev = im->interface;
 839
 840	spin_lock(&im->lock);
 841	im->tm_running = 0;
 842
 843	if (im->unsolicit_count && --im->unsolicit_count)
 844		igmp_start_timer(im, unsolicited_report_interval(in_dev));
 845
 846	im->reporter = 1;
 847	spin_unlock(&im->lock);
 848
 849	if (IGMP_V1_SEEN(in_dev))
 850		igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
 851	else if (IGMP_V2_SEEN(in_dev))
 852		igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
 853	else
 854		igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
 855
 856	ip_ma_put(im);
 857}
 858
 859/* mark EXCLUDE-mode sources */
 860static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 861{
 862	struct ip_sf_list *psf;
 863	int i, scount;
 864
 865	scount = 0;
 866	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 867		if (scount == nsrcs)
 868			break;
 869		for (i = 0; i < nsrcs; i++) {
 870			/* skip inactive filters */
 871			if (psf->sf_count[MCAST_INCLUDE] ||
 872			    pmc->sfcount[MCAST_EXCLUDE] !=
 873			    psf->sf_count[MCAST_EXCLUDE])
 874				break;
 875			if (srcs[i] == psf->sf_inaddr) {
 876				scount++;
 877				break;
 878			}
 879		}
 880	}
 881	pmc->gsquery = 0;
 882	if (scount == nsrcs)	/* all sources excluded */
 883		return 0;
 884	return 1;
 885}
 886
 887static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 888{
 889	struct ip_sf_list *psf;
 890	int i, scount;
 891
 892	if (pmc->sfmode == MCAST_EXCLUDE)
 893		return igmp_xmarksources(pmc, nsrcs, srcs);
 894
 895	/* mark INCLUDE-mode sources */
 896	scount = 0;
 897	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 898		if (scount == nsrcs)
 899			break;
 900		for (i = 0; i < nsrcs; i++)
 901			if (srcs[i] == psf->sf_inaddr) {
 902				psf->sf_gsresp = 1;
 903				scount++;
 904				break;
 905			}
 906	}
 907	if (!scount) {
 908		pmc->gsquery = 0;
 909		return 0;
 910	}
 911	pmc->gsquery = 1;
 912	return 1;
 913}
 914
 915/* return true if packet was dropped */
 916static bool igmp_heard_report(struct in_device *in_dev, __be32 group)
 917{
 918	struct ip_mc_list *im;
 919	struct net *net = dev_net(in_dev->dev);
 920
 921	/* Timers are only set for non-local groups */
 922
 923	if (group == IGMP_ALL_HOSTS)
 924		return false;
 925	if (ipv4_is_local_multicast(group) &&
 926	    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
 927		return false;
 928
 929	rcu_read_lock();
 930	for_each_pmc_rcu(in_dev, im) {
 931		if (im->multiaddr == group) {
 932			igmp_stop_timer(im);
 933			break;
 934		}
 935	}
 936	rcu_read_unlock();
 937	return false;
 938}
 939
 940/* return true if packet was dropped */
 941static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
 942	int len)
 943{
 944	struct igmphdr 		*ih = igmp_hdr(skb);
 945	struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
 946	struct ip_mc_list	*im;
 947	__be32			group = ih->group;
 948	int			max_delay;
 949	int			mark = 0;
 950	struct net		*net = dev_net(in_dev->dev);
 951
 952
 953	if (len == 8) {
 954		if (ih->code == 0) {
 955			/* Alas, old v1 router presents here. */
 956
 957			max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 958			in_dev->mr_v1_seen = jiffies +
 959				(in_dev->mr_qrv * in_dev->mr_qi) +
 960				in_dev->mr_qri;
 961			group = 0;
 962		} else {
 963			/* v2 router present */
 964			max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
 965			in_dev->mr_v2_seen = jiffies +
 966				(in_dev->mr_qrv * in_dev->mr_qi) +
 967				in_dev->mr_qri;
 968		}
 969		/* cancel the interface change timer */
 970		WRITE_ONCE(in_dev->mr_ifc_count, 0);
 971		if (del_timer(&in_dev->mr_ifc_timer))
 972			__in_dev_put(in_dev);
 973		/* clear deleted report items */
 974		igmpv3_clear_delrec(in_dev);
 975	} else if (len < 12) {
 976		return true;	/* ignore bogus packet; freed by caller */
 977	} else if (IGMP_V1_SEEN(in_dev)) {
 978		/* This is a v3 query with v1 queriers present */
 979		max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 980		group = 0;
 981	} else if (IGMP_V2_SEEN(in_dev)) {
 982		/* this is a v3 query with v2 queriers present;
 983		 * Interpretation of the max_delay code is problematic here.
 984		 * A real v2 host would use ih_code directly, while v3 has a
 985		 * different encoding. We use the v3 encoding as more likely
 986		 * to be intended in a v3 query.
 987		 */
 988		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 989		if (!max_delay)
 990			max_delay = 1;	/* can't mod w/ 0 */
 991	} else { /* v3 */
 992		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
 993			return true;
 994
 995		ih3 = igmpv3_query_hdr(skb);
 996		if (ih3->nsrcs) {
 997			if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
 998					   + ntohs(ih3->nsrcs)*sizeof(__be32)))
 999				return true;
1000			ih3 = igmpv3_query_hdr(skb);
1001		}
1002
1003		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
1004		if (!max_delay)
1005			max_delay = 1;	/* can't mod w/ 0 */
1006		in_dev->mr_maxdelay = max_delay;
1007
1008		/* RFC3376, 4.1.6. QRV and 4.1.7. QQIC, when the most recently
1009		 * received value was zero, use the default or statically
1010		 * configured value.
1011		 */
1012		in_dev->mr_qrv = ih3->qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1013		in_dev->mr_qi = IGMPV3_QQIC(ih3->qqic)*HZ ?: IGMP_QUERY_INTERVAL;
1014
1015		/* RFC3376, 8.3. Query Response Interval:
1016		 * The number of seconds represented by the [Query Response
1017		 * Interval] must be less than the [Query Interval].
1018		 */
1019		if (in_dev->mr_qri >= in_dev->mr_qi)
1020			in_dev->mr_qri = (in_dev->mr_qi/HZ - 1)*HZ;
1021
1022		if (!group) { /* general query */
1023			if (ih3->nsrcs)
1024				return true;	/* no sources allowed */
1025			igmp_gq_start_timer(in_dev);
1026			return false;
1027		}
1028		/* mark sources to include, if group & source-specific */
1029		mark = ih3->nsrcs != 0;
1030	}
1031
1032	/*
1033	 * - Start the timers in all of our membership records
1034	 *   that the query applies to for the interface on
1035	 *   which the query arrived excl. those that belong
1036	 *   to a "local" group (224.0.0.X)
1037	 * - For timers already running check if they need to
1038	 *   be reset.
1039	 * - Use the igmp->igmp_code field as the maximum
1040	 *   delay possible
1041	 */
1042	rcu_read_lock();
1043	for_each_pmc_rcu(in_dev, im) {
1044		int changed;
1045
1046		if (group && group != im->multiaddr)
1047			continue;
1048		if (im->multiaddr == IGMP_ALL_HOSTS)
1049			continue;
1050		if (ipv4_is_local_multicast(im->multiaddr) &&
1051		    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
1052			continue;
1053		spin_lock_bh(&im->lock);
1054		if (im->tm_running)
1055			im->gsquery = im->gsquery && mark;
1056		else
1057			im->gsquery = mark;
1058		changed = !im->gsquery ||
1059			igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
1060		spin_unlock_bh(&im->lock);
1061		if (changed)
1062			igmp_mod_timer(im, max_delay);
1063	}
1064	rcu_read_unlock();
1065	return false;
1066}
1067
1068/* called in rcu_read_lock() section */
1069int igmp_rcv(struct sk_buff *skb)
1070{
1071	/* This basically follows the spec line by line -- see RFC1112 */
1072	struct igmphdr *ih;
1073	struct net_device *dev = skb->dev;
1074	struct in_device *in_dev;
1075	int len = skb->len;
1076	bool dropped = true;
1077
1078	if (netif_is_l3_master(dev)) {
1079		dev = dev_get_by_index_rcu(dev_net(dev), IPCB(skb)->iif);
1080		if (!dev)
1081			goto drop;
1082	}
1083
1084	in_dev = __in_dev_get_rcu(dev);
1085	if (!in_dev)
1086		goto drop;
1087
1088	if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
1089		goto drop;
1090
1091	if (skb_checksum_simple_validate(skb))
1092		goto drop;
1093
1094	ih = igmp_hdr(skb);
1095	switch (ih->type) {
1096	case IGMP_HOST_MEMBERSHIP_QUERY:
1097		dropped = igmp_heard_query(in_dev, skb, len);
1098		break;
1099	case IGMP_HOST_MEMBERSHIP_REPORT:
1100	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1101		/* Is it our report looped back? */
1102		if (rt_is_output_route(skb_rtable(skb)))
1103			break;
1104		/* don't rely on MC router hearing unicast reports */
1105		if (skb->pkt_type == PACKET_MULTICAST ||
1106		    skb->pkt_type == PACKET_BROADCAST)
1107			dropped = igmp_heard_report(in_dev, ih->group);
1108		break;
1109	case IGMP_PIM:
1110#ifdef CONFIG_IP_PIMSM_V1
1111		return pim_rcv_v1(skb);
1112#endif
1113	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1114	case IGMP_DVMRP:
1115	case IGMP_TRACE:
1116	case IGMP_HOST_LEAVE_MESSAGE:
1117	case IGMP_MTRACE:
1118	case IGMP_MTRACE_RESP:
1119		break;
1120	default:
1121		break;
1122	}
1123
1124drop:
1125	if (dropped)
1126		kfree_skb(skb);
1127	else
1128		consume_skb(skb);
1129	return 0;
1130}
1131
1132#endif
1133
1134
1135/*
1136 *	Add a filter to a device
1137 */
1138
1139static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1140{
1141	char buf[MAX_ADDR_LEN];
1142	struct net_device *dev = in_dev->dev;
1143
1144	/* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1145	   We will get multicast token leakage, when IFF_MULTICAST
1146	   is changed. This check should be done in ndo_set_rx_mode
1147	   routine. Something sort of:
1148	   if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1149	   --ANK
1150	   */
1151	if (arp_mc_map(addr, buf, dev, 0) == 0)
1152		dev_mc_add(dev, buf);
1153}
1154
1155/*
1156 *	Remove a filter from a device
1157 */
1158
1159static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1160{
1161	char buf[MAX_ADDR_LEN];
1162	struct net_device *dev = in_dev->dev;
1163
1164	if (arp_mc_map(addr, buf, dev, 0) == 0)
1165		dev_mc_del(dev, buf);
1166}
1167
1168#ifdef CONFIG_IP_MULTICAST
1169/*
1170 * deleted ip_mc_list manipulation
1171 */
1172static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im,
1173			      gfp_t gfp)
1174{
1175	struct ip_mc_list *pmc;
1176	struct net *net = dev_net(in_dev->dev);
1177
1178	/* this is an "ip_mc_list" for convenience; only the fields below
1179	 * are actually used. In particular, the refcnt and users are not
1180	 * used for management of the delete list. Using the same structure
1181	 * for deleted items allows change reports to use common code with
1182	 * non-deleted or query-response MCA's.
1183	 */
1184	pmc = kzalloc(sizeof(*pmc), gfp);
1185	if (!pmc)
1186		return;
1187	spin_lock_init(&pmc->lock);
1188	spin_lock_bh(&im->lock);
1189	pmc->interface = im->interface;
1190	in_dev_hold(in_dev);
1191	pmc->multiaddr = im->multiaddr;
1192	pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1193	pmc->sfmode = im->sfmode;
1194	if (pmc->sfmode == MCAST_INCLUDE) {
1195		struct ip_sf_list *psf;
1196
1197		pmc->tomb = im->tomb;
1198		pmc->sources = im->sources;
1199		im->tomb = im->sources = NULL;
1200		for (psf = pmc->sources; psf; psf = psf->sf_next)
1201			psf->sf_crcount = pmc->crcount;
1202	}
1203	spin_unlock_bh(&im->lock);
1204
1205	spin_lock_bh(&in_dev->mc_tomb_lock);
1206	pmc->next = in_dev->mc_tomb;
1207	in_dev->mc_tomb = pmc;
1208	spin_unlock_bh(&in_dev->mc_tomb_lock);
1209}
1210
1211/*
1212 * restore ip_mc_list deleted records
1213 */
1214static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1215{
1216	struct ip_mc_list *pmc, *pmc_prev;
1217	struct ip_sf_list *psf;
1218	struct net *net = dev_net(in_dev->dev);
1219	__be32 multiaddr = im->multiaddr;
1220
1221	spin_lock_bh(&in_dev->mc_tomb_lock);
1222	pmc_prev = NULL;
1223	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) {
1224		if (pmc->multiaddr == multiaddr)
1225			break;
1226		pmc_prev = pmc;
1227	}
1228	if (pmc) {
1229		if (pmc_prev)
1230			pmc_prev->next = pmc->next;
1231		else
1232			in_dev->mc_tomb = pmc->next;
1233	}
1234	spin_unlock_bh(&in_dev->mc_tomb_lock);
1235
1236	spin_lock_bh(&im->lock);
1237	if (pmc) {
1238		im->interface = pmc->interface;
1239		if (im->sfmode == MCAST_INCLUDE) {
1240			swap(im->tomb, pmc->tomb);
1241			swap(im->sources, pmc->sources);
1242			for (psf = im->sources; psf; psf = psf->sf_next)
1243				psf->sf_crcount = in_dev->mr_qrv ?:
1244					READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1245		} else {
1246			im->crcount = in_dev->mr_qrv ?:
1247				READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1248		}
1249		in_dev_put(pmc->interface);
1250		kfree_pmc(pmc);
1251	}
1252	spin_unlock_bh(&im->lock);
1253}
1254
1255/*
1256 * flush ip_mc_list deleted records
1257 */
1258static void igmpv3_clear_delrec(struct in_device *in_dev)
1259{
1260	struct ip_mc_list *pmc, *nextpmc;
1261
1262	spin_lock_bh(&in_dev->mc_tomb_lock);
1263	pmc = in_dev->mc_tomb;
1264	in_dev->mc_tomb = NULL;
1265	spin_unlock_bh(&in_dev->mc_tomb_lock);
1266
1267	for (; pmc; pmc = nextpmc) {
1268		nextpmc = pmc->next;
1269		ip_mc_clear_src(pmc);
1270		in_dev_put(pmc->interface);
1271		kfree_pmc(pmc);
1272	}
1273	/* clear dead sources, too */
1274	rcu_read_lock();
1275	for_each_pmc_rcu(in_dev, pmc) {
1276		struct ip_sf_list *psf;
1277
1278		spin_lock_bh(&pmc->lock);
1279		psf = pmc->tomb;
1280		pmc->tomb = NULL;
1281		spin_unlock_bh(&pmc->lock);
1282		ip_sf_list_clear_all(psf);
1283	}
1284	rcu_read_unlock();
1285}
1286#endif
1287
1288static void __igmp_group_dropped(struct ip_mc_list *im, gfp_t gfp)
1289{
1290	struct in_device *in_dev = im->interface;
1291#ifdef CONFIG_IP_MULTICAST
1292	struct net *net = dev_net(in_dev->dev);
1293	int reporter;
1294#endif
1295
1296	if (im->loaded) {
1297		im->loaded = 0;
1298		ip_mc_filter_del(in_dev, im->multiaddr);
1299	}
1300
1301#ifdef CONFIG_IP_MULTICAST
1302	if (im->multiaddr == IGMP_ALL_HOSTS)
1303		return;
1304	if (ipv4_is_local_multicast(im->multiaddr) &&
1305	    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
1306		return;
1307
1308	reporter = im->reporter;
1309	igmp_stop_timer(im);
1310
1311	if (!in_dev->dead) {
1312		if (IGMP_V1_SEEN(in_dev))
1313			return;
1314		if (IGMP_V2_SEEN(in_dev)) {
1315			if (reporter)
1316				igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1317			return;
1318		}
1319		/* IGMPv3 */
1320		igmpv3_add_delrec(in_dev, im, gfp);
1321
1322		igmp_ifc_event(in_dev);
1323	}
1324#endif
1325}
1326
1327static void igmp_group_dropped(struct ip_mc_list *im)
1328{
1329	__igmp_group_dropped(im, GFP_KERNEL);
1330}
1331
1332static void igmp_group_added(struct ip_mc_list *im)
1333{
1334	struct in_device *in_dev = im->interface;
1335#ifdef CONFIG_IP_MULTICAST
1336	struct net *net = dev_net(in_dev->dev);
1337#endif
1338
1339	if (im->loaded == 0) {
1340		im->loaded = 1;
1341		ip_mc_filter_add(in_dev, im->multiaddr);
1342	}
1343
1344#ifdef CONFIG_IP_MULTICAST
1345	if (im->multiaddr == IGMP_ALL_HOSTS)
1346		return;
1347	if (ipv4_is_local_multicast(im->multiaddr) &&
1348	    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
1349		return;
1350
1351	if (in_dev->dead)
1352		return;
1353
1354	im->unsolicit_count = READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1355	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1356		spin_lock_bh(&im->lock);
1357		igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY);
1358		spin_unlock_bh(&im->lock);
1359		return;
1360	}
1361	/* else, v3 */
1362
1363	/* Based on RFC3376 5.1, for newly added INCLUDE SSM, we should
1364	 * not send filter-mode change record as the mode should be from
1365	 * IN() to IN(A).
1366	 */
1367	if (im->sfmode == MCAST_EXCLUDE)
1368		im->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1369
1370	igmp_ifc_event(in_dev);
1371#endif
1372}
1373
1374
1375/*
1376 *	Multicast list managers
1377 */
1378
1379static u32 ip_mc_hash(const struct ip_mc_list *im)
1380{
1381	return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
1382}
1383
1384static void ip_mc_hash_add(struct in_device *in_dev,
1385			   struct ip_mc_list *im)
1386{
1387	struct ip_mc_list __rcu **mc_hash;
1388	u32 hash;
1389
1390	mc_hash = rtnl_dereference(in_dev->mc_hash);
1391	if (mc_hash) {
1392		hash = ip_mc_hash(im);
1393		im->next_hash = mc_hash[hash];
1394		rcu_assign_pointer(mc_hash[hash], im);
1395		return;
1396	}
1397
1398	/* do not use a hash table for small number of items */
1399	if (in_dev->mc_count < 4)
1400		return;
1401
1402	mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
1403			  GFP_KERNEL);
1404	if (!mc_hash)
1405		return;
1406
1407	for_each_pmc_rtnl(in_dev, im) {
1408		hash = ip_mc_hash(im);
1409		im->next_hash = mc_hash[hash];
1410		RCU_INIT_POINTER(mc_hash[hash], im);
1411	}
1412
1413	rcu_assign_pointer(in_dev->mc_hash, mc_hash);
1414}
1415
1416static void ip_mc_hash_remove(struct in_device *in_dev,
1417			      struct ip_mc_list *im)
1418{
1419	struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
1420	struct ip_mc_list *aux;
1421
1422	if (!mc_hash)
1423		return;
1424	mc_hash += ip_mc_hash(im);
1425	while ((aux = rtnl_dereference(*mc_hash)) != im)
1426		mc_hash = &aux->next_hash;
1427	*mc_hash = im->next_hash;
1428}
1429
1430
1431/*
1432 *	A socket has joined a multicast group on device dev.
1433 */
1434static void ____ip_mc_inc_group(struct in_device *in_dev, __be32 addr,
1435				unsigned int mode, gfp_t gfp)
1436{
 
1437	struct ip_mc_list *im;
1438
1439	ASSERT_RTNL();
1440
1441	for_each_pmc_rtnl(in_dev, im) {
1442		if (im->multiaddr == addr) {
1443			im->users++;
1444			ip_mc_add_src(in_dev, &addr, mode, 0, NULL, 0);
1445			goto out;
 
 
 
 
 
 
 
 
 
1446		}
1447	}
1448
 
 
 
 
 
 
1449	im = kzalloc(sizeof(*im), gfp);
1450	if (!im)
1451		goto out;
1452
1453	im->users = 1;
1454	im->interface = in_dev;
1455	in_dev_hold(in_dev);
1456	im->multiaddr = addr;
1457	/* initial mode is (EX, empty) */
1458	im->sfmode = mode;
1459	im->sfcount[mode] = 1;
1460	refcount_set(&im->refcnt, 1);
1461	spin_lock_init(&im->lock);
1462#ifdef CONFIG_IP_MULTICAST
1463	timer_setup(&im->timer, igmp_timer_expire, 0);
1464#endif
1465
1466	im->next_rcu = in_dev->mc_list;
1467	in_dev->mc_count++;
1468	rcu_assign_pointer(in_dev->mc_list, im);
1469
1470	ip_mc_hash_add(in_dev, im);
1471
1472#ifdef CONFIG_IP_MULTICAST
1473	igmpv3_del_delrec(in_dev, im);
1474#endif
1475	igmp_group_added(im);
1476	if (!in_dev->dead)
1477		ip_rt_multicast_event(in_dev);
1478out:
1479	return;
1480}
1481
1482void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr, gfp_t gfp)
1483{
1484	____ip_mc_inc_group(in_dev, addr, MCAST_EXCLUDE, gfp);
1485}
1486EXPORT_SYMBOL(__ip_mc_inc_group);
1487
1488void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1489{
1490	__ip_mc_inc_group(in_dev, addr, GFP_KERNEL);
1491}
1492EXPORT_SYMBOL(ip_mc_inc_group);
1493
1494static int ip_mc_check_iphdr(struct sk_buff *skb)
1495{
1496	const struct iphdr *iph;
1497	unsigned int len;
1498	unsigned int offset = skb_network_offset(skb) + sizeof(*iph);
1499
1500	if (!pskb_may_pull(skb, offset))
1501		return -EINVAL;
1502
1503	iph = ip_hdr(skb);
1504
1505	if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph))
1506		return -EINVAL;
1507
1508	offset += ip_hdrlen(skb) - sizeof(*iph);
1509
1510	if (!pskb_may_pull(skb, offset))
1511		return -EINVAL;
1512
1513	iph = ip_hdr(skb);
1514
1515	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1516		return -EINVAL;
1517
1518	len = skb_network_offset(skb) + ntohs(iph->tot_len);
1519	if (skb->len < len || len < offset)
1520		return -EINVAL;
1521
1522	skb_set_transport_header(skb, offset);
1523
1524	return 0;
1525}
1526
1527static int ip_mc_check_igmp_reportv3(struct sk_buff *skb)
1528{
1529	unsigned int len = skb_transport_offset(skb);
1530
1531	len += sizeof(struct igmpv3_report);
1532
1533	return ip_mc_may_pull(skb, len) ? 0 : -EINVAL;
1534}
1535
1536static int ip_mc_check_igmp_query(struct sk_buff *skb)
1537{
1538	unsigned int transport_len = ip_transport_len(skb);
1539	unsigned int len;
1540
1541	/* IGMPv{1,2}? */
1542	if (transport_len != sizeof(struct igmphdr)) {
1543		/* or IGMPv3? */
1544		if (transport_len < sizeof(struct igmpv3_query))
1545			return -EINVAL;
1546
1547		len = skb_transport_offset(skb) + sizeof(struct igmpv3_query);
1548		if (!ip_mc_may_pull(skb, len))
1549			return -EINVAL;
1550	}
1551
1552	/* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1553	 * all-systems destination addresses (224.0.0.1) for general queries
1554	 */
1555	if (!igmp_hdr(skb)->group &&
1556	    ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP))
1557		return -EINVAL;
1558
1559	return 0;
1560}
1561
1562static int ip_mc_check_igmp_msg(struct sk_buff *skb)
1563{
1564	switch (igmp_hdr(skb)->type) {
1565	case IGMP_HOST_LEAVE_MESSAGE:
1566	case IGMP_HOST_MEMBERSHIP_REPORT:
1567	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1568		return 0;
1569	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1570		return ip_mc_check_igmp_reportv3(skb);
1571	case IGMP_HOST_MEMBERSHIP_QUERY:
1572		return ip_mc_check_igmp_query(skb);
1573	default:
1574		return -ENOMSG;
1575	}
1576}
1577
1578static __sum16 ip_mc_validate_checksum(struct sk_buff *skb)
1579{
1580	return skb_checksum_simple_validate(skb);
1581}
1582
1583static int ip_mc_check_igmp_csum(struct sk_buff *skb)
1584{
1585	unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr);
1586	unsigned int transport_len = ip_transport_len(skb);
1587	struct sk_buff *skb_chk;
1588
1589	if (!ip_mc_may_pull(skb, len))
1590		return -EINVAL;
1591
1592	skb_chk = skb_checksum_trimmed(skb, transport_len,
1593				       ip_mc_validate_checksum);
1594	if (!skb_chk)
1595		return -EINVAL;
1596
1597	if (skb_chk != skb)
1598		kfree_skb(skb_chk);
1599
1600	return 0;
1601}
1602
1603/**
1604 * ip_mc_check_igmp - checks whether this is a sane IGMP packet
1605 * @skb: the skb to validate
1606 *
1607 * Checks whether an IPv4 packet is a valid IGMP packet. If so sets
1608 * skb transport header accordingly and returns zero.
1609 *
1610 * -EINVAL: A broken packet was detected, i.e. it violates some internet
1611 *  standard
1612 * -ENOMSG: IP header validation succeeded but it is not an IGMP packet.
1613 * -ENOMEM: A memory allocation failure happened.
1614 *
1615 * Caller needs to set the skb network header and free any returned skb if it
1616 * differs from the provided skb.
1617 */
1618int ip_mc_check_igmp(struct sk_buff *skb)
1619{
1620	int ret = ip_mc_check_iphdr(skb);
1621
1622	if (ret < 0)
1623		return ret;
1624
1625	if (ip_hdr(skb)->protocol != IPPROTO_IGMP)
1626		return -ENOMSG;
1627
1628	ret = ip_mc_check_igmp_csum(skb);
1629	if (ret < 0)
1630		return ret;
1631
1632	return ip_mc_check_igmp_msg(skb);
1633}
1634EXPORT_SYMBOL(ip_mc_check_igmp);
1635
1636/*
1637 *	Resend IGMP JOIN report; used by netdev notifier.
1638 */
1639static void ip_mc_rejoin_groups(struct in_device *in_dev)
1640{
1641#ifdef CONFIG_IP_MULTICAST
1642	struct ip_mc_list *im;
1643	int type;
1644	struct net *net = dev_net(in_dev->dev);
1645
1646	ASSERT_RTNL();
1647
1648	for_each_pmc_rtnl(in_dev, im) {
1649		if (im->multiaddr == IGMP_ALL_HOSTS)
1650			continue;
1651		if (ipv4_is_local_multicast(im->multiaddr) &&
1652		    !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
1653			continue;
1654
1655		/* a failover is happening and switches
1656		 * must be notified immediately
1657		 */
1658		if (IGMP_V1_SEEN(in_dev))
1659			type = IGMP_HOST_MEMBERSHIP_REPORT;
1660		else if (IGMP_V2_SEEN(in_dev))
1661			type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1662		else
1663			type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1664		igmp_send_report(in_dev, im, type);
1665	}
1666#endif
1667}
1668
1669/*
1670 *	A socket has left a multicast group on device dev
1671 */
1672
1673void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp)
1674{
1675	struct ip_mc_list *i;
1676	struct ip_mc_list __rcu **ip;
1677
1678	ASSERT_RTNL();
1679
1680	for (ip = &in_dev->mc_list;
1681	     (i = rtnl_dereference(*ip)) != NULL;
1682	     ip = &i->next_rcu) {
1683		if (i->multiaddr == addr) {
1684			if (--i->users == 0) {
1685				ip_mc_hash_remove(in_dev, i);
1686				*ip = i->next_rcu;
1687				in_dev->mc_count--;
1688				__igmp_group_dropped(i, gfp);
1689				ip_mc_clear_src(i);
1690
1691				if (!in_dev->dead)
1692					ip_rt_multicast_event(in_dev);
1693
1694				ip_ma_put(i);
1695				return;
1696			}
1697			break;
1698		}
1699	}
1700}
1701EXPORT_SYMBOL(__ip_mc_dec_group);
1702
1703/* Device changing type */
1704
1705void ip_mc_unmap(struct in_device *in_dev)
1706{
1707	struct ip_mc_list *pmc;
1708
1709	ASSERT_RTNL();
1710
1711	for_each_pmc_rtnl(in_dev, pmc)
1712		igmp_group_dropped(pmc);
1713}
1714
1715void ip_mc_remap(struct in_device *in_dev)
1716{
1717	struct ip_mc_list *pmc;
1718
1719	ASSERT_RTNL();
1720
1721	for_each_pmc_rtnl(in_dev, pmc) {
1722#ifdef CONFIG_IP_MULTICAST
1723		igmpv3_del_delrec(in_dev, pmc);
1724#endif
1725		igmp_group_added(pmc);
1726	}
1727}
1728
1729/* Device going down */
1730
1731void ip_mc_down(struct in_device *in_dev)
1732{
1733	struct ip_mc_list *pmc;
1734
1735	ASSERT_RTNL();
1736
1737	for_each_pmc_rtnl(in_dev, pmc)
1738		igmp_group_dropped(pmc);
1739
1740#ifdef CONFIG_IP_MULTICAST
1741	WRITE_ONCE(in_dev->mr_ifc_count, 0);
1742	if (del_timer(&in_dev->mr_ifc_timer))
1743		__in_dev_put(in_dev);
1744	in_dev->mr_gq_running = 0;
1745	if (del_timer(&in_dev->mr_gq_timer))
1746		__in_dev_put(in_dev);
1747#endif
1748
1749	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1750}
1751
1752#ifdef CONFIG_IP_MULTICAST
1753static void ip_mc_reset(struct in_device *in_dev)
1754{
1755	struct net *net = dev_net(in_dev->dev);
1756
1757	in_dev->mr_qi = IGMP_QUERY_INTERVAL;
1758	in_dev->mr_qri = IGMP_QUERY_RESPONSE_INTERVAL;
1759	in_dev->mr_qrv = READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1760}
1761#else
1762static void ip_mc_reset(struct in_device *in_dev)
1763{
1764}
1765#endif
1766
1767void ip_mc_init_dev(struct in_device *in_dev)
1768{
1769	ASSERT_RTNL();
1770
1771#ifdef CONFIG_IP_MULTICAST
1772	timer_setup(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 0);
1773	timer_setup(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 0);
1774#endif
1775	ip_mc_reset(in_dev);
1776
1777	spin_lock_init(&in_dev->mc_tomb_lock);
1778}
1779
1780/* Device going up */
1781
1782void ip_mc_up(struct in_device *in_dev)
1783{
1784	struct ip_mc_list *pmc;
1785
1786	ASSERT_RTNL();
1787
1788	ip_mc_reset(in_dev);
1789	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1790
1791	for_each_pmc_rtnl(in_dev, pmc) {
1792#ifdef CONFIG_IP_MULTICAST
1793		igmpv3_del_delrec(in_dev, pmc);
1794#endif
1795		igmp_group_added(pmc);
1796	}
1797}
1798
1799/*
1800 *	Device is about to be destroyed: clean up.
1801 */
1802
1803void ip_mc_destroy_dev(struct in_device *in_dev)
1804{
1805	struct ip_mc_list *i;
1806
1807	ASSERT_RTNL();
1808
1809	/* Deactivate timers */
1810	ip_mc_down(in_dev);
1811#ifdef CONFIG_IP_MULTICAST
1812	igmpv3_clear_delrec(in_dev);
1813#endif
1814
1815	while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1816		in_dev->mc_list = i->next_rcu;
1817		in_dev->mc_count--;
1818		ip_mc_clear_src(i);
1819		ip_ma_put(i);
1820	}
1821}
1822
1823/* RTNL is locked */
1824static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1825{
1826	struct net_device *dev = NULL;
1827	struct in_device *idev = NULL;
1828
1829	if (imr->imr_ifindex) {
1830		idev = inetdev_by_index(net, imr->imr_ifindex);
1831		return idev;
1832	}
1833	if (imr->imr_address.s_addr) {
1834		dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1835		if (!dev)
1836			return NULL;
1837	}
1838
1839	if (!dev) {
1840		struct rtable *rt = ip_route_output(net,
1841						    imr->imr_multiaddr.s_addr,
1842						    0, 0, 0);
 
1843		if (!IS_ERR(rt)) {
1844			dev = rt->dst.dev;
1845			ip_rt_put(rt);
1846		}
1847	}
1848	if (dev) {
1849		imr->imr_ifindex = dev->ifindex;
1850		idev = __in_dev_get_rtnl(dev);
1851	}
1852	return idev;
1853}
1854
1855/*
1856 *	Join a socket to a group
1857 */
1858
1859static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1860	__be32 *psfsrc)
1861{
1862	struct ip_sf_list *psf, *psf_prev;
1863	int rv = 0;
1864
1865	psf_prev = NULL;
1866	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1867		if (psf->sf_inaddr == *psfsrc)
1868			break;
1869		psf_prev = psf;
1870	}
1871	if (!psf || psf->sf_count[sfmode] == 0) {
1872		/* source filter not found, or count wrong =>  bug */
1873		return -ESRCH;
1874	}
1875	psf->sf_count[sfmode]--;
1876	if (psf->sf_count[sfmode] == 0) {
1877		ip_rt_multicast_event(pmc->interface);
1878	}
1879	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1880#ifdef CONFIG_IP_MULTICAST
1881		struct in_device *in_dev = pmc->interface;
1882		struct net *net = dev_net(in_dev->dev);
1883#endif
1884
1885		/* no more filters for this source */
1886		if (psf_prev)
1887			psf_prev->sf_next = psf->sf_next;
1888		else
1889			pmc->sources = psf->sf_next;
1890#ifdef CONFIG_IP_MULTICAST
1891		if (psf->sf_oldin &&
1892		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1893			psf->sf_crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1894			psf->sf_next = pmc->tomb;
1895			pmc->tomb = psf;
1896			rv = 1;
1897		} else
1898#endif
1899			kfree(psf);
1900	}
1901	return rv;
1902}
1903
1904#ifndef CONFIG_IP_MULTICAST
1905#define igmp_ifc_event(x)	do { } while (0)
1906#endif
1907
1908static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1909			 int sfcount, __be32 *psfsrc, int delta)
1910{
1911	struct ip_mc_list *pmc;
1912	int	changerec = 0;
1913	int	i, err;
1914
1915	if (!in_dev)
1916		return -ENODEV;
1917	rcu_read_lock();
1918	for_each_pmc_rcu(in_dev, pmc) {
1919		if (*pmca == pmc->multiaddr)
1920			break;
1921	}
1922	if (!pmc) {
1923		/* MCA not found?? bug */
1924		rcu_read_unlock();
1925		return -ESRCH;
1926	}
1927	spin_lock_bh(&pmc->lock);
1928	rcu_read_unlock();
1929#ifdef CONFIG_IP_MULTICAST
1930	sf_markstate(pmc);
1931#endif
1932	if (!delta) {
1933		err = -EINVAL;
1934		if (!pmc->sfcount[sfmode])
1935			goto out_unlock;
1936		pmc->sfcount[sfmode]--;
1937	}
1938	err = 0;
1939	for (i = 0; i < sfcount; i++) {
1940		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1941
1942		changerec |= rv > 0;
1943		if (!err && rv < 0)
1944			err = rv;
1945	}
1946	if (pmc->sfmode == MCAST_EXCLUDE &&
1947	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1948	    pmc->sfcount[MCAST_INCLUDE]) {
1949#ifdef CONFIG_IP_MULTICAST
1950		struct ip_sf_list *psf;
1951		struct net *net = dev_net(in_dev->dev);
1952#endif
1953
1954		/* filter mode change */
1955		pmc->sfmode = MCAST_INCLUDE;
1956#ifdef CONFIG_IP_MULTICAST
1957		pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1958		WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount);
1959		for (psf = pmc->sources; psf; psf = psf->sf_next)
1960			psf->sf_crcount = 0;
1961		igmp_ifc_event(pmc->interface);
1962	} else if (sf_setstate(pmc) || changerec) {
1963		igmp_ifc_event(pmc->interface);
1964#endif
1965	}
1966out_unlock:
1967	spin_unlock_bh(&pmc->lock);
1968	return err;
1969}
1970
1971/*
1972 * Add multicast single-source filter to the interface list
1973 */
1974static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1975	__be32 *psfsrc)
1976{
1977	struct ip_sf_list *psf, *psf_prev;
1978
1979	psf_prev = NULL;
1980	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1981		if (psf->sf_inaddr == *psfsrc)
1982			break;
1983		psf_prev = psf;
1984	}
1985	if (!psf) {
1986		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1987		if (!psf)
1988			return -ENOBUFS;
1989		psf->sf_inaddr = *psfsrc;
1990		if (psf_prev) {
1991			psf_prev->sf_next = psf;
1992		} else
1993			pmc->sources = psf;
1994	}
1995	psf->sf_count[sfmode]++;
1996	if (psf->sf_count[sfmode] == 1) {
1997		ip_rt_multicast_event(pmc->interface);
1998	}
1999	return 0;
2000}
2001
2002#ifdef CONFIG_IP_MULTICAST
2003static void sf_markstate(struct ip_mc_list *pmc)
2004{
2005	struct ip_sf_list *psf;
2006	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
2007
2008	for (psf = pmc->sources; psf; psf = psf->sf_next)
2009		if (pmc->sfcount[MCAST_EXCLUDE]) {
2010			psf->sf_oldin = mca_xcount ==
2011				psf->sf_count[MCAST_EXCLUDE] &&
2012				!psf->sf_count[MCAST_INCLUDE];
2013		} else
2014			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2015}
2016
2017static int sf_setstate(struct ip_mc_list *pmc)
2018{
2019	struct ip_sf_list *psf, *dpsf;
2020	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
2021	int qrv = pmc->interface->mr_qrv;
2022	int new_in, rv;
2023
2024	rv = 0;
2025	for (psf = pmc->sources; psf; psf = psf->sf_next) {
2026		if (pmc->sfcount[MCAST_EXCLUDE]) {
2027			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2028				!psf->sf_count[MCAST_INCLUDE];
2029		} else
2030			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2031		if (new_in) {
2032			if (!psf->sf_oldin) {
2033				struct ip_sf_list *prev = NULL;
2034
2035				for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) {
2036					if (dpsf->sf_inaddr == psf->sf_inaddr)
2037						break;
2038					prev = dpsf;
2039				}
2040				if (dpsf) {
2041					if (prev)
2042						prev->sf_next = dpsf->sf_next;
2043					else
2044						pmc->tomb = dpsf->sf_next;
2045					kfree(dpsf);
2046				}
2047				psf->sf_crcount = qrv;
2048				rv++;
2049			}
2050		} else if (psf->sf_oldin) {
2051
2052			psf->sf_crcount = 0;
2053			/*
2054			 * add or update "delete" records if an active filter
2055			 * is now inactive
2056			 */
2057			for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next)
2058				if (dpsf->sf_inaddr == psf->sf_inaddr)
2059					break;
2060			if (!dpsf) {
2061				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
2062				if (!dpsf)
2063					continue;
2064				*dpsf = *psf;
2065				/* pmc->lock held by callers */
2066				dpsf->sf_next = pmc->tomb;
2067				pmc->tomb = dpsf;
2068			}
2069			dpsf->sf_crcount = qrv;
2070			rv++;
2071		}
2072	}
2073	return rv;
2074}
2075#endif
2076
2077/*
2078 * Add multicast source filter list to the interface list
2079 */
2080static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
2081			 int sfcount, __be32 *psfsrc, int delta)
2082{
2083	struct ip_mc_list *pmc;
2084	int	isexclude;
2085	int	i, err;
2086
2087	if (!in_dev)
2088		return -ENODEV;
2089	rcu_read_lock();
2090	for_each_pmc_rcu(in_dev, pmc) {
2091		if (*pmca == pmc->multiaddr)
2092			break;
2093	}
2094	if (!pmc) {
2095		/* MCA not found?? bug */
2096		rcu_read_unlock();
2097		return -ESRCH;
2098	}
2099	spin_lock_bh(&pmc->lock);
2100	rcu_read_unlock();
2101
2102#ifdef CONFIG_IP_MULTICAST
2103	sf_markstate(pmc);
2104#endif
2105	isexclude = pmc->sfmode == MCAST_EXCLUDE;
2106	if (!delta)
2107		pmc->sfcount[sfmode]++;
2108	err = 0;
2109	for (i = 0; i < sfcount; i++) {
2110		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2111		if (err)
2112			break;
2113	}
2114	if (err) {
2115		int j;
2116
2117		if (!delta)
2118			pmc->sfcount[sfmode]--;
2119		for (j = 0; j < i; j++)
2120			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2121	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
2122#ifdef CONFIG_IP_MULTICAST
2123		struct ip_sf_list *psf;
2124		struct net *net = dev_net(pmc->interface->dev);
2125		in_dev = pmc->interface;
2126#endif
2127
2128		/* filter mode change */
2129		if (pmc->sfcount[MCAST_EXCLUDE])
2130			pmc->sfmode = MCAST_EXCLUDE;
2131		else if (pmc->sfcount[MCAST_INCLUDE])
2132			pmc->sfmode = MCAST_INCLUDE;
2133#ifdef CONFIG_IP_MULTICAST
2134		/* else no filters; keep old mode for reports */
2135
2136		pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
2137		WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount);
2138		for (psf = pmc->sources; psf; psf = psf->sf_next)
2139			psf->sf_crcount = 0;
2140		igmp_ifc_event(in_dev);
2141	} else if (sf_setstate(pmc)) {
2142		igmp_ifc_event(in_dev);
2143#endif
2144	}
2145	spin_unlock_bh(&pmc->lock);
2146	return err;
2147}
2148
2149static void ip_mc_clear_src(struct ip_mc_list *pmc)
2150{
2151	struct ip_sf_list *tomb, *sources;
2152
2153	spin_lock_bh(&pmc->lock);
2154	tomb = pmc->tomb;
2155	pmc->tomb = NULL;
2156	sources = pmc->sources;
2157	pmc->sources = NULL;
2158	pmc->sfmode = MCAST_EXCLUDE;
2159	pmc->sfcount[MCAST_INCLUDE] = 0;
2160	pmc->sfcount[MCAST_EXCLUDE] = 1;
2161	spin_unlock_bh(&pmc->lock);
2162
2163	ip_sf_list_clear_all(tomb);
2164	ip_sf_list_clear_all(sources);
2165}
2166
2167/* Join a multicast group
2168 */
2169static int __ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr,
2170			      unsigned int mode)
2171{
2172	__be32 addr = imr->imr_multiaddr.s_addr;
2173	struct ip_mc_socklist *iml, *i;
2174	struct in_device *in_dev;
2175	struct inet_sock *inet = inet_sk(sk);
2176	struct net *net = sock_net(sk);
2177	int ifindex;
2178	int count = 0;
2179	int err;
2180
2181	ASSERT_RTNL();
2182
2183	if (!ipv4_is_multicast(addr))
2184		return -EINVAL;
2185
2186	in_dev = ip_mc_find_dev(net, imr);
2187
2188	if (!in_dev) {
2189		err = -ENODEV;
2190		goto done;
2191	}
2192
2193	err = -EADDRINUSE;
2194	ifindex = imr->imr_ifindex;
2195	for_each_pmc_rtnl(inet, i) {
2196		if (i->multi.imr_multiaddr.s_addr == addr &&
2197		    i->multi.imr_ifindex == ifindex)
2198			goto done;
2199		count++;
2200	}
2201	err = -ENOBUFS;
2202	if (count >= READ_ONCE(net->ipv4.sysctl_igmp_max_memberships))
2203		goto done;
2204	iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
2205	if (!iml)
2206		goto done;
2207
2208	memcpy(&iml->multi, imr, sizeof(*imr));
2209	iml->next_rcu = inet->mc_list;
2210	iml->sflist = NULL;
2211	iml->sfmode = mode;
2212	rcu_assign_pointer(inet->mc_list, iml);
2213	____ip_mc_inc_group(in_dev, addr, mode, GFP_KERNEL);
2214	err = 0;
2215done:
2216	return err;
2217}
2218
2219/* Join ASM (Any-Source Multicast) group
2220 */
2221int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
2222{
2223	return __ip_mc_join_group(sk, imr, MCAST_EXCLUDE);
2224}
2225EXPORT_SYMBOL(ip_mc_join_group);
2226
2227/* Join SSM (Source-Specific Multicast) group
2228 */
2229int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr,
2230			 unsigned int mode)
2231{
2232	return __ip_mc_join_group(sk, imr, mode);
2233}
2234
2235static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
2236			   struct in_device *in_dev)
2237{
2238	struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
2239	int err;
2240
2241	if (!psf) {
2242		/* any-source empty exclude case */
2243		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2244			iml->sfmode, 0, NULL, 0);
2245	}
2246	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2247			iml->sfmode, psf->sl_count, psf->sl_addr, 0);
2248	RCU_INIT_POINTER(iml->sflist, NULL);
2249	/* decrease mem now to avoid the memleak warning */
2250	atomic_sub(struct_size(psf, sl_addr, psf->sl_max), &sk->sk_omem_alloc);
2251	kfree_rcu(psf, rcu);
2252	return err;
2253}
2254
2255int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
2256{
2257	struct inet_sock *inet = inet_sk(sk);
2258	struct ip_mc_socklist *iml;
2259	struct ip_mc_socklist __rcu **imlp;
2260	struct in_device *in_dev;
2261	struct net *net = sock_net(sk);
2262	__be32 group = imr->imr_multiaddr.s_addr;
2263	u32 ifindex;
2264	int ret = -EADDRNOTAVAIL;
2265
2266	ASSERT_RTNL();
2267
2268	in_dev = ip_mc_find_dev(net, imr);
2269	if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) {
2270		ret = -ENODEV;
2271		goto out;
2272	}
2273	ifindex = imr->imr_ifindex;
2274	for (imlp = &inet->mc_list;
2275	     (iml = rtnl_dereference(*imlp)) != NULL;
2276	     imlp = &iml->next_rcu) {
2277		if (iml->multi.imr_multiaddr.s_addr != group)
2278			continue;
2279		if (ifindex) {
2280			if (iml->multi.imr_ifindex != ifindex)
2281				continue;
2282		} else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
2283				iml->multi.imr_address.s_addr)
2284			continue;
2285
2286		(void) ip_mc_leave_src(sk, iml, in_dev);
2287
2288		*imlp = iml->next_rcu;
2289
2290		if (in_dev)
2291			ip_mc_dec_group(in_dev, group);
2292
2293		/* decrease mem now to avoid the memleak warning */
2294		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2295		kfree_rcu(iml, rcu);
2296		return 0;
2297	}
2298out:
2299	return ret;
2300}
2301EXPORT_SYMBOL(ip_mc_leave_group);
2302
2303int ip_mc_source(int add, int omode, struct sock *sk, struct
2304	ip_mreq_source *mreqs, int ifindex)
2305{
2306	int err;
2307	struct ip_mreqn imr;
2308	__be32 addr = mreqs->imr_multiaddr;
2309	struct ip_mc_socklist *pmc;
2310	struct in_device *in_dev = NULL;
2311	struct inet_sock *inet = inet_sk(sk);
2312	struct ip_sf_socklist *psl;
2313	struct net *net = sock_net(sk);
2314	int leavegroup = 0;
2315	int i, j, rv;
2316
2317	if (!ipv4_is_multicast(addr))
2318		return -EINVAL;
2319
2320	ASSERT_RTNL();
2321
2322	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
2323	imr.imr_address.s_addr = mreqs->imr_interface;
2324	imr.imr_ifindex = ifindex;
2325	in_dev = ip_mc_find_dev(net, &imr);
2326
2327	if (!in_dev) {
2328		err = -ENODEV;
2329		goto done;
2330	}
2331	err = -EADDRNOTAVAIL;
2332
2333	for_each_pmc_rtnl(inet, pmc) {
2334		if ((pmc->multi.imr_multiaddr.s_addr ==
2335		     imr.imr_multiaddr.s_addr) &&
2336		    (pmc->multi.imr_ifindex == imr.imr_ifindex))
2337			break;
2338	}
2339	if (!pmc) {		/* must have a prior join */
2340		err = -EINVAL;
2341		goto done;
2342	}
2343	/* if a source filter was set, must be the same mode as before */
2344	if (pmc->sflist) {
2345		if (pmc->sfmode != omode) {
2346			err = -EINVAL;
2347			goto done;
2348		}
2349	} else if (pmc->sfmode != omode) {
2350		/* allow mode switches for empty-set filters */
2351		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
2352		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
2353			NULL, 0);
2354		pmc->sfmode = omode;
2355	}
2356
2357	psl = rtnl_dereference(pmc->sflist);
2358	if (!add) {
2359		if (!psl)
2360			goto done;	/* err = -EADDRNOTAVAIL */
2361		rv = !0;
2362		for (i = 0; i < psl->sl_count; i++) {
2363			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2364				sizeof(__be32));
2365			if (rv == 0)
2366				break;
2367		}
2368		if (rv)		/* source not found */
2369			goto done;	/* err = -EADDRNOTAVAIL */
2370
2371		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2372		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
2373			leavegroup = 1;
2374			goto done;
2375		}
2376
2377		/* update the interface filter */
2378		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2379			&mreqs->imr_sourceaddr, 1);
2380
2381		for (j = i+1; j < psl->sl_count; j++)
2382			psl->sl_addr[j-1] = psl->sl_addr[j];
2383		psl->sl_count--;
2384		err = 0;
2385		goto done;
2386	}
2387	/* else, add a new source to the filter */
2388
2389	if (psl && psl->sl_count >= READ_ONCE(net->ipv4.sysctl_igmp_max_msf)) {
2390		err = -ENOBUFS;
2391		goto done;
2392	}
2393	if (!psl || psl->sl_count == psl->sl_max) {
2394		struct ip_sf_socklist *newpsl;
2395		int count = IP_SFBLOCK;
2396
2397		if (psl)
2398			count += psl->sl_max;
2399		newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr, count),
2400				      GFP_KERNEL);
2401		if (!newpsl) {
2402			err = -ENOBUFS;
2403			goto done;
2404		}
2405		newpsl->sl_max = count;
2406		newpsl->sl_count = count - IP_SFBLOCK;
2407		if (psl) {
2408			for (i = 0; i < psl->sl_count; i++)
2409				newpsl->sl_addr[i] = psl->sl_addr[i];
2410			/* decrease mem now to avoid the memleak warning */
2411			atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
2412				   &sk->sk_omem_alloc);
2413		}
2414		rcu_assign_pointer(pmc->sflist, newpsl);
2415		if (psl)
2416			kfree_rcu(psl, rcu);
2417		psl = newpsl;
2418	}
2419	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
2420	for (i = 0; i < psl->sl_count; i++) {
2421		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2422			sizeof(__be32));
2423		if (rv == 0)
2424			break;
2425	}
2426	if (rv == 0)		/* address already there is an error */
2427		goto done;
2428	for (j = psl->sl_count-1; j >= i; j--)
2429		psl->sl_addr[j+1] = psl->sl_addr[j];
2430	psl->sl_addr[i] = mreqs->imr_sourceaddr;
2431	psl->sl_count++;
2432	err = 0;
2433	/* update the interface list */
2434	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2435		&mreqs->imr_sourceaddr, 1);
2436done:
2437	if (leavegroup)
2438		err = ip_mc_leave_group(sk, &imr);
2439	return err;
2440}
2441
2442int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2443{
2444	int err = 0;
2445	struct ip_mreqn	imr;
2446	__be32 addr = msf->imsf_multiaddr;
2447	struct ip_mc_socklist *pmc;
2448	struct in_device *in_dev;
2449	struct inet_sock *inet = inet_sk(sk);
2450	struct ip_sf_socklist *newpsl, *psl;
2451	struct net *net = sock_net(sk);
2452	int leavegroup = 0;
2453
2454	if (!ipv4_is_multicast(addr))
2455		return -EINVAL;
2456	if (msf->imsf_fmode != MCAST_INCLUDE &&
2457	    msf->imsf_fmode != MCAST_EXCLUDE)
2458		return -EINVAL;
2459
2460	ASSERT_RTNL();
2461
2462	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2463	imr.imr_address.s_addr = msf->imsf_interface;
2464	imr.imr_ifindex = ifindex;
2465	in_dev = ip_mc_find_dev(net, &imr);
2466
2467	if (!in_dev) {
2468		err = -ENODEV;
2469		goto done;
2470	}
2471
2472	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2473	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2474		leavegroup = 1;
2475		goto done;
2476	}
2477
2478	for_each_pmc_rtnl(inet, pmc) {
2479		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2480		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2481			break;
2482	}
2483	if (!pmc) {		/* must have a prior join */
2484		err = -EINVAL;
2485		goto done;
2486	}
2487	if (msf->imsf_numsrc) {
2488		newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr,
2489						      msf->imsf_numsrc),
2490				      GFP_KERNEL);
2491		if (!newpsl) {
2492			err = -ENOBUFS;
2493			goto done;
2494		}
2495		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2496		memcpy(newpsl->sl_addr, msf->imsf_slist_flex,
2497		       flex_array_size(msf, imsf_slist_flex, msf->imsf_numsrc));
2498		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2499			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2500		if (err) {
2501			sock_kfree_s(sk, newpsl,
2502				     struct_size(newpsl, sl_addr,
2503						 newpsl->sl_max));
2504			goto done;
2505		}
2506	} else {
2507		newpsl = NULL;
2508		(void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2509				     msf->imsf_fmode, 0, NULL, 0);
2510	}
2511	psl = rtnl_dereference(pmc->sflist);
2512	if (psl) {
2513		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2514			psl->sl_count, psl->sl_addr, 0);
2515		/* decrease mem now to avoid the memleak warning */
2516		atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
2517			   &sk->sk_omem_alloc);
2518	} else {
2519		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2520			0, NULL, 0);
2521	}
2522	rcu_assign_pointer(pmc->sflist, newpsl);
2523	if (psl)
2524		kfree_rcu(psl, rcu);
2525	pmc->sfmode = msf->imsf_fmode;
2526	err = 0;
2527done:
2528	if (leavegroup)
2529		err = ip_mc_leave_group(sk, &imr);
2530	return err;
2531}
2532int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2533		 sockptr_t optval, sockptr_t optlen)
2534{
2535	int err, len, count, copycount, msf_size;
2536	struct ip_mreqn	imr;
2537	__be32 addr = msf->imsf_multiaddr;
2538	struct ip_mc_socklist *pmc;
2539	struct in_device *in_dev;
2540	struct inet_sock *inet = inet_sk(sk);
2541	struct ip_sf_socklist *psl;
2542	struct net *net = sock_net(sk);
2543
2544	ASSERT_RTNL();
2545
2546	if (!ipv4_is_multicast(addr))
2547		return -EINVAL;
2548
2549	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2550	imr.imr_address.s_addr = msf->imsf_interface;
2551	imr.imr_ifindex = 0;
2552	in_dev = ip_mc_find_dev(net, &imr);
2553
2554	if (!in_dev) {
2555		err = -ENODEV;
2556		goto done;
2557	}
2558	err = -EADDRNOTAVAIL;
2559
2560	for_each_pmc_rtnl(inet, pmc) {
2561		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2562		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2563			break;
2564	}
2565	if (!pmc)		/* must have a prior join */
2566		goto done;
2567	msf->imsf_fmode = pmc->sfmode;
2568	psl = rtnl_dereference(pmc->sflist);
2569	if (!psl) {
2570		count = 0;
2571	} else {
2572		count = psl->sl_count;
2573	}
2574	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2575	len = flex_array_size(psl, sl_addr, copycount);
2576	msf->imsf_numsrc = count;
2577	msf_size = IP_MSFILTER_SIZE(copycount);
2578	if (copy_to_sockptr(optlen, &msf_size, sizeof(int)) ||
2579	    copy_to_sockptr(optval, msf, IP_MSFILTER_SIZE(0))) {
2580		return -EFAULT;
2581	}
2582	if (len &&
2583	    copy_to_sockptr_offset(optval,
2584				   offsetof(struct ip_msfilter, imsf_slist_flex),
2585				   psl->sl_addr, len))
2586		return -EFAULT;
2587	return 0;
2588done:
2589	return err;
2590}
2591
2592int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2593		 sockptr_t optval, size_t ss_offset)
2594{
2595	int i, count, copycount;
2596	struct sockaddr_in *psin;
2597	__be32 addr;
2598	struct ip_mc_socklist *pmc;
2599	struct inet_sock *inet = inet_sk(sk);
2600	struct ip_sf_socklist *psl;
2601
2602	ASSERT_RTNL();
2603
2604	psin = (struct sockaddr_in *)&gsf->gf_group;
2605	if (psin->sin_family != AF_INET)
2606		return -EINVAL;
2607	addr = psin->sin_addr.s_addr;
2608	if (!ipv4_is_multicast(addr))
2609		return -EINVAL;
2610
2611	for_each_pmc_rtnl(inet, pmc) {
2612		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2613		    pmc->multi.imr_ifindex == gsf->gf_interface)
2614			break;
2615	}
2616	if (!pmc)		/* must have a prior join */
2617		return -EADDRNOTAVAIL;
2618	gsf->gf_fmode = pmc->sfmode;
2619	psl = rtnl_dereference(pmc->sflist);
2620	count = psl ? psl->sl_count : 0;
2621	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2622	gsf->gf_numsrc = count;
2623	for (i = 0; i < copycount; i++) {
2624		struct sockaddr_storage ss;
2625
2626		psin = (struct sockaddr_in *)&ss;
2627		memset(&ss, 0, sizeof(ss));
2628		psin->sin_family = AF_INET;
2629		psin->sin_addr.s_addr = psl->sl_addr[i];
2630		if (copy_to_sockptr_offset(optval, ss_offset,
2631					   &ss, sizeof(ss)))
2632			return -EFAULT;
2633		ss_offset += sizeof(ss);
2634	}
2635	return 0;
2636}
2637
2638/*
2639 * check if a multicast source filter allows delivery for a given <src,dst,intf>
2640 */
2641int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr,
2642		   int dif, int sdif)
2643{
2644	struct inet_sock *inet = inet_sk(sk);
2645	struct ip_mc_socklist *pmc;
2646	struct ip_sf_socklist *psl;
2647	int i;
2648	int ret;
2649
2650	ret = 1;
2651	if (!ipv4_is_multicast(loc_addr))
2652		goto out;
2653
2654	rcu_read_lock();
2655	for_each_pmc_rcu(inet, pmc) {
2656		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2657		    (pmc->multi.imr_ifindex == dif ||
2658		     (sdif && pmc->multi.imr_ifindex == sdif)))
2659			break;
2660	}
2661	ret = inet->mc_all;
2662	if (!pmc)
2663		goto unlock;
2664	psl = rcu_dereference(pmc->sflist);
2665	ret = (pmc->sfmode == MCAST_EXCLUDE);
2666	if (!psl)
2667		goto unlock;
2668
2669	for (i = 0; i < psl->sl_count; i++) {
2670		if (psl->sl_addr[i] == rmt_addr)
2671			break;
2672	}
2673	ret = 0;
2674	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2675		goto unlock;
2676	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2677		goto unlock;
2678	ret = 1;
2679unlock:
2680	rcu_read_unlock();
2681out:
2682	return ret;
2683}
2684
2685/*
2686 *	A socket is closing.
2687 */
2688
2689void ip_mc_drop_socket(struct sock *sk)
2690{
2691	struct inet_sock *inet = inet_sk(sk);
2692	struct ip_mc_socklist *iml;
2693	struct net *net = sock_net(sk);
2694
2695	if (!inet->mc_list)
2696		return;
2697
2698	rtnl_lock();
2699	while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2700		struct in_device *in_dev;
2701
2702		inet->mc_list = iml->next_rcu;
2703		in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2704		(void) ip_mc_leave_src(sk, iml, in_dev);
2705		if (in_dev)
2706			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2707		/* decrease mem now to avoid the memleak warning */
2708		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2709		kfree_rcu(iml, rcu);
2710	}
2711	rtnl_unlock();
2712}
2713
2714/* called with rcu_read_lock() */
2715int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto)
2716{
2717	struct ip_mc_list *im;
2718	struct ip_mc_list __rcu **mc_hash;
2719	struct ip_sf_list *psf;
2720	int rv = 0;
2721
2722	mc_hash = rcu_dereference(in_dev->mc_hash);
2723	if (mc_hash) {
2724		u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
2725
2726		for (im = rcu_dereference(mc_hash[hash]);
2727		     im != NULL;
2728		     im = rcu_dereference(im->next_hash)) {
2729			if (im->multiaddr == mc_addr)
2730				break;
2731		}
2732	} else {
2733		for_each_pmc_rcu(in_dev, im) {
2734			if (im->multiaddr == mc_addr)
2735				break;
2736		}
2737	}
2738	if (im && proto == IPPROTO_IGMP) {
2739		rv = 1;
2740	} else if (im) {
2741		if (src_addr) {
2742			spin_lock_bh(&im->lock);
2743			for (psf = im->sources; psf; psf = psf->sf_next) {
2744				if (psf->sf_inaddr == src_addr)
2745					break;
2746			}
2747			if (psf)
2748				rv = psf->sf_count[MCAST_INCLUDE] ||
2749					psf->sf_count[MCAST_EXCLUDE] !=
2750					im->sfcount[MCAST_EXCLUDE];
2751			else
2752				rv = im->sfcount[MCAST_EXCLUDE] != 0;
2753			spin_unlock_bh(&im->lock);
2754		} else
2755			rv = 1; /* unspecified source; tentatively allow */
2756	}
2757	return rv;
2758}
2759
2760#if defined(CONFIG_PROC_FS)
2761struct igmp_mc_iter_state {
2762	struct seq_net_private p;
2763	struct net_device *dev;
2764	struct in_device *in_dev;
2765};
2766
2767#define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2768
2769static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2770{
2771	struct net *net = seq_file_net(seq);
2772	struct ip_mc_list *im = NULL;
2773	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2774
2775	state->in_dev = NULL;
2776	for_each_netdev_rcu(net, state->dev) {
2777		struct in_device *in_dev;
2778
2779		in_dev = __in_dev_get_rcu(state->dev);
2780		if (!in_dev)
2781			continue;
2782		im = rcu_dereference(in_dev->mc_list);
2783		if (im) {
2784			state->in_dev = in_dev;
2785			break;
2786		}
2787	}
2788	return im;
2789}
2790
2791static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2792{
2793	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2794
2795	im = rcu_dereference(im->next_rcu);
2796	while (!im) {
2797		state->dev = next_net_device_rcu(state->dev);
2798		if (!state->dev) {
2799			state->in_dev = NULL;
2800			break;
2801		}
2802		state->in_dev = __in_dev_get_rcu(state->dev);
2803		if (!state->in_dev)
2804			continue;
2805		im = rcu_dereference(state->in_dev->mc_list);
2806	}
2807	return im;
2808}
2809
2810static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2811{
2812	struct ip_mc_list *im = igmp_mc_get_first(seq);
2813	if (im)
2814		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2815			--pos;
2816	return pos ? NULL : im;
2817}
2818
2819static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2820	__acquires(rcu)
2821{
2822	rcu_read_lock();
2823	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2824}
2825
2826static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2827{
2828	struct ip_mc_list *im;
2829	if (v == SEQ_START_TOKEN)
2830		im = igmp_mc_get_first(seq);
2831	else
2832		im = igmp_mc_get_next(seq, v);
2833	++*pos;
2834	return im;
2835}
2836
2837static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2838	__releases(rcu)
2839{
2840	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2841
2842	state->in_dev = NULL;
2843	state->dev = NULL;
2844	rcu_read_unlock();
2845}
2846
2847static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2848{
2849	if (v == SEQ_START_TOKEN)
2850		seq_puts(seq,
2851			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2852	else {
2853		struct ip_mc_list *im = v;
2854		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2855		char   *querier;
2856		long delta;
2857
2858#ifdef CONFIG_IP_MULTICAST
2859		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2860			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2861			  "V3";
2862#else
2863		querier = "NONE";
2864#endif
2865
2866		if (rcu_access_pointer(state->in_dev->mc_list) == im) {
2867			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2868				   state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2869		}
2870
2871		delta = im->timer.expires - jiffies;
2872		seq_printf(seq,
2873			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2874			   im->multiaddr, im->users,
2875			   im->tm_running,
2876			   im->tm_running ? jiffies_delta_to_clock_t(delta) : 0,
2877			   im->reporter);
2878	}
2879	return 0;
2880}
2881
2882static const struct seq_operations igmp_mc_seq_ops = {
2883	.start	=	igmp_mc_seq_start,
2884	.next	=	igmp_mc_seq_next,
2885	.stop	=	igmp_mc_seq_stop,
2886	.show	=	igmp_mc_seq_show,
2887};
2888
2889struct igmp_mcf_iter_state {
2890	struct seq_net_private p;
2891	struct net_device *dev;
2892	struct in_device *idev;
2893	struct ip_mc_list *im;
2894};
2895
2896#define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2897
2898static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2899{
2900	struct net *net = seq_file_net(seq);
2901	struct ip_sf_list *psf = NULL;
2902	struct ip_mc_list *im = NULL;
2903	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2904
2905	state->idev = NULL;
2906	state->im = NULL;
2907	for_each_netdev_rcu(net, state->dev) {
2908		struct in_device *idev;
2909		idev = __in_dev_get_rcu(state->dev);
2910		if (unlikely(!idev))
2911			continue;
2912		im = rcu_dereference(idev->mc_list);
2913		if (likely(im)) {
2914			spin_lock_bh(&im->lock);
2915			psf = im->sources;
2916			if (likely(psf)) {
2917				state->im = im;
2918				state->idev = idev;
2919				break;
2920			}
2921			spin_unlock_bh(&im->lock);
2922		}
2923	}
2924	return psf;
2925}
2926
2927static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2928{
2929	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2930
2931	psf = psf->sf_next;
2932	while (!psf) {
2933		spin_unlock_bh(&state->im->lock);
2934		state->im = state->im->next;
2935		while (!state->im) {
2936			state->dev = next_net_device_rcu(state->dev);
2937			if (!state->dev) {
2938				state->idev = NULL;
2939				goto out;
2940			}
2941			state->idev = __in_dev_get_rcu(state->dev);
2942			if (!state->idev)
2943				continue;
2944			state->im = rcu_dereference(state->idev->mc_list);
2945		}
2946		if (!state->im)
2947			break;
2948		spin_lock_bh(&state->im->lock);
2949		psf = state->im->sources;
2950	}
2951out:
2952	return psf;
2953}
2954
2955static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2956{
2957	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2958	if (psf)
2959		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2960			--pos;
2961	return pos ? NULL : psf;
2962}
2963
2964static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2965	__acquires(rcu)
2966{
2967	rcu_read_lock();
2968	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2969}
2970
2971static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2972{
2973	struct ip_sf_list *psf;
2974	if (v == SEQ_START_TOKEN)
2975		psf = igmp_mcf_get_first(seq);
2976	else
2977		psf = igmp_mcf_get_next(seq, v);
2978	++*pos;
2979	return psf;
2980}
2981
2982static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2983	__releases(rcu)
2984{
2985	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2986	if (likely(state->im)) {
2987		spin_unlock_bh(&state->im->lock);
2988		state->im = NULL;
2989	}
2990	state->idev = NULL;
2991	state->dev = NULL;
2992	rcu_read_unlock();
2993}
2994
2995static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2996{
2997	struct ip_sf_list *psf = v;
2998	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2999
3000	if (v == SEQ_START_TOKEN) {
3001		seq_puts(seq, "Idx Device        MCA        SRC    INC    EXC\n");
3002	} else {
3003		seq_printf(seq,
3004			   "%3d %6.6s 0x%08x "
3005			   "0x%08x %6lu %6lu\n",
3006			   state->dev->ifindex, state->dev->name,
3007			   ntohl(state->im->multiaddr),
3008			   ntohl(psf->sf_inaddr),
3009			   psf->sf_count[MCAST_INCLUDE],
3010			   psf->sf_count[MCAST_EXCLUDE]);
3011	}
3012	return 0;
3013}
3014
3015static const struct seq_operations igmp_mcf_seq_ops = {
3016	.start	=	igmp_mcf_seq_start,
3017	.next	=	igmp_mcf_seq_next,
3018	.stop	=	igmp_mcf_seq_stop,
3019	.show	=	igmp_mcf_seq_show,
3020};
3021
3022static int __net_init igmp_net_init(struct net *net)
3023{
3024	struct proc_dir_entry *pde;
3025	int err;
3026
3027	pde = proc_create_net("igmp", 0444, net->proc_net, &igmp_mc_seq_ops,
3028			sizeof(struct igmp_mc_iter_state));
3029	if (!pde)
3030		goto out_igmp;
3031	pde = proc_create_net("mcfilter", 0444, net->proc_net,
3032			&igmp_mcf_seq_ops, sizeof(struct igmp_mcf_iter_state));
3033	if (!pde)
3034		goto out_mcfilter;
3035	err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET,
3036				   SOCK_DGRAM, 0, net);
3037	if (err < 0) {
3038		pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n",
3039		       err);
3040		goto out_sock;
3041	}
3042
3043	return 0;
3044
3045out_sock:
3046	remove_proc_entry("mcfilter", net->proc_net);
3047out_mcfilter:
3048	remove_proc_entry("igmp", net->proc_net);
3049out_igmp:
3050	return -ENOMEM;
3051}
3052
3053static void __net_exit igmp_net_exit(struct net *net)
3054{
3055	remove_proc_entry("mcfilter", net->proc_net);
3056	remove_proc_entry("igmp", net->proc_net);
3057	inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk);
3058}
3059
3060static struct pernet_operations igmp_net_ops = {
3061	.init = igmp_net_init,
3062	.exit = igmp_net_exit,
3063};
3064#endif
3065
3066static int igmp_netdev_event(struct notifier_block *this,
3067			     unsigned long event, void *ptr)
3068{
3069	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3070	struct in_device *in_dev;
3071
3072	switch (event) {
3073	case NETDEV_RESEND_IGMP:
3074		in_dev = __in_dev_get_rtnl(dev);
3075		if (in_dev)
3076			ip_mc_rejoin_groups(in_dev);
3077		break;
3078	default:
3079		break;
3080	}
3081	return NOTIFY_DONE;
3082}
3083
3084static struct notifier_block igmp_notifier = {
3085	.notifier_call = igmp_netdev_event,
3086};
3087
3088int __init igmp_mc_init(void)
3089{
3090#if defined(CONFIG_PROC_FS)
3091	int err;
3092
3093	err = register_pernet_subsys(&igmp_net_ops);
3094	if (err)
3095		return err;
3096	err = register_netdevice_notifier(&igmp_notifier);
3097	if (err)
3098		goto reg_notif_fail;
3099	return 0;
3100
3101reg_notif_fail:
3102	unregister_pernet_subsys(&igmp_net_ops);
3103	return err;
3104#else
3105	return register_netdevice_notifier(&igmp_notifier);
3106#endif
3107}