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v5.4
   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_V2_UNSOLICITED_REPORT_INTERVAL	(10*HZ)
 111#define IGMP_V3_UNSOLICITED_REPORT_INTERVAL	(1*HZ)
 112#define IGMP_QUERY_INTERVAL			(125*HZ)
 113#define IGMP_QUERY_RESPONSE_INTERVAL		(10*HZ)
 114
 115#define IGMP_INITIAL_REPORT_DELAY		(1)
 116
 117/* IGMP_INITIAL_REPORT_DELAY is not from IGMP specs!
 118 * IGMP specs require to report membership immediately after
 119 * joining a group, but we delay the first report by a
 120 * small interval. It seems more natural and still does not
 121 * contradict to specs provided this delay is small enough.
 122 */
 123
 124#define IGMP_V1_SEEN(in_dev) \
 125	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \
 126	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \
 127	 ((in_dev)->mr_v1_seen && \
 128	  time_before(jiffies, (in_dev)->mr_v1_seen)))
 129#define IGMP_V2_SEEN(in_dev) \
 130	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \
 131	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \
 132	 ((in_dev)->mr_v2_seen && \
 133	  time_before(jiffies, (in_dev)->mr_v2_seen)))
 134
 135static int unsolicited_report_interval(struct in_device *in_dev)
 136{
 137	int interval_ms, interval_jiffies;
 138
 139	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 140		interval_ms = IN_DEV_CONF_GET(
 141			in_dev,
 142			IGMPV2_UNSOLICITED_REPORT_INTERVAL);
 143	else /* v3 */
 144		interval_ms = IN_DEV_CONF_GET(
 145			in_dev,
 146			IGMPV3_UNSOLICITED_REPORT_INTERVAL);
 147
 148	interval_jiffies = msecs_to_jiffies(interval_ms);
 149
 150	/* _timer functions can't handle a delay of 0 jiffies so ensure
 151	 *  we always return a positive value.
 152	 */
 153	if (interval_jiffies <= 0)
 154		interval_jiffies = 1;
 155	return interval_jiffies;
 156}
 157
 158static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im,
 159			      gfp_t gfp);
 160static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im);
 161static void igmpv3_clear_delrec(struct in_device *in_dev);
 162static int sf_setstate(struct ip_mc_list *pmc);
 163static void sf_markstate(struct ip_mc_list *pmc);
 164#endif
 165static void ip_mc_clear_src(struct ip_mc_list *pmc);
 166static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
 167			 int sfcount, __be32 *psfsrc, int delta);
 168
 169static void ip_ma_put(struct ip_mc_list *im)
 170{
 171	if (refcount_dec_and_test(&im->refcnt)) {
 172		in_dev_put(im->interface);
 173		kfree_rcu(im, rcu);
 174	}
 175}
 176
 177#define for_each_pmc_rcu(in_dev, pmc)				\
 178	for (pmc = rcu_dereference(in_dev->mc_list);		\
 179	     pmc != NULL;					\
 180	     pmc = rcu_dereference(pmc->next_rcu))
 181
 182#define for_each_pmc_rtnl(in_dev, pmc)				\
 183	for (pmc = rtnl_dereference(in_dev->mc_list);		\
 184	     pmc != NULL;					\
 185	     pmc = rtnl_dereference(pmc->next_rcu))
 186
 187static void ip_sf_list_clear_all(struct ip_sf_list *psf)
 188{
 189	struct ip_sf_list *next;
 190
 191	while (psf) {
 192		next = psf->sf_next;
 193		kfree(psf);
 194		psf = next;
 195	}
 196}
 197
 198#ifdef CONFIG_IP_MULTICAST
 199
 200/*
 201 *	Timer management
 202 */
 203
 204static void igmp_stop_timer(struct ip_mc_list *im)
 205{
 206	spin_lock_bh(&im->lock);
 207	if (del_timer(&im->timer))
 208		refcount_dec(&im->refcnt);
 209	im->tm_running = 0;
 210	im->reporter = 0;
 211	im->unsolicit_count = 0;
 212	spin_unlock_bh(&im->lock);
 213}
 214
 215/* It must be called with locked im->lock */
 216static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
 217{
 218	int tv = prandom_u32() % max_delay;
 219
 220	im->tm_running = 1;
 221	if (!mod_timer(&im->timer, jiffies+tv+2))
 222		refcount_inc(&im->refcnt);
 
 
 223}
 224
 225static void igmp_gq_start_timer(struct in_device *in_dev)
 226{
 227	int tv = prandom_u32() % 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 = prandom_u32() % 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 = mtu;
 359
 
 360	while (1) {
 361		skb = alloc_skb(size + hlen + tlen,
 362				GFP_ATOMIC | __GFP_NOWARN);
 363		if (skb)
 364			break;
 365		size >>= 1;
 366		if (size < 256)
 367			return NULL;
 368	}
 369	skb->priority = TC_PRIO_CONTROL;
 370
 371	rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0,
 372				   0, 0,
 373				   IPPROTO_IGMP, 0, dev->ifindex);
 374	if (IS_ERR(rt)) {
 375		kfree_skb(skb);
 376		return NULL;
 377	}
 378
 379	skb_dst_set(skb, &rt->dst);
 380	skb->dev = dev;
 381
 382	skb_reserve(skb, hlen);
 383	skb_tailroom_reserve(skb, mtu, tlen);
 384
 385	skb_reset_network_header(skb);
 386	pip = ip_hdr(skb);
 387	skb_put(skb, sizeof(struct iphdr) + 4);
 388
 389	pip->version  = 4;
 390	pip->ihl      = (sizeof(struct iphdr)+4)>>2;
 391	pip->tos      = 0xc0;
 392	pip->frag_off = htons(IP_DF);
 393	pip->ttl      = 1;
 394	pip->daddr    = fl4.daddr;
 395
 396	rcu_read_lock();
 397	pip->saddr    = igmpv3_get_srcaddr(dev, &fl4);
 398	rcu_read_unlock();
 399
 400	pip->protocol = IPPROTO_IGMP;
 401	pip->tot_len  = 0;	/* filled in later */
 402	ip_select_ident(net, skb, NULL);
 403	((u8 *)&pip[1])[0] = IPOPT_RA;
 404	((u8 *)&pip[1])[1] = 4;
 405	((u8 *)&pip[1])[2] = 0;
 406	((u8 *)&pip[1])[3] = 0;
 407
 408	skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
 409	skb_put(skb, sizeof(*pig));
 410	pig = igmpv3_report_hdr(skb);
 411	pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
 412	pig->resv1 = 0;
 413	pig->csum = 0;
 414	pig->resv2 = 0;
 415	pig->ngrec = 0;
 416	return skb;
 417}
 418
 419static int igmpv3_sendpack(struct sk_buff *skb)
 420{
 421	struct igmphdr *pig = igmp_hdr(skb);
 422	const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
 423
 424	pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
 425
 426	return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
 427}
 428
 429static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
 430{
 431	return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
 432}
 433
 434static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
 435	int type, struct igmpv3_grec **ppgr, unsigned int mtu)
 436{
 437	struct net_device *dev = pmc->interface->dev;
 438	struct igmpv3_report *pih;
 439	struct igmpv3_grec *pgr;
 440
 441	if (!skb) {
 442		skb = igmpv3_newpack(dev, mtu);
 443		if (!skb)
 444			return NULL;
 445	}
 446	pgr = skb_put(skb, sizeof(struct igmpv3_grec));
 447	pgr->grec_type = type;
 448	pgr->grec_auxwords = 0;
 449	pgr->grec_nsrcs = 0;
 450	pgr->grec_mca = pmc->multiaddr;
 451	pih = igmpv3_report_hdr(skb);
 452	pih->ngrec = htons(ntohs(pih->ngrec)+1);
 453	*ppgr = pgr;
 454	return skb;
 455}
 456
 457#define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
 458
 459static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
 460	int type, int gdeleted, int sdeleted)
 461{
 462	struct net_device *dev = pmc->interface->dev;
 463	struct net *net = dev_net(dev);
 464	struct igmpv3_report *pih;
 465	struct igmpv3_grec *pgr = NULL;
 466	struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
 467	int scount, stotal, first, isquery, truncate;
 468	unsigned int mtu;
 469
 470	if (pmc->multiaddr == IGMP_ALL_HOSTS)
 471		return skb;
 472	if (ipv4_is_local_multicast(pmc->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
 
 473		return skb;
 474
 475	mtu = READ_ONCE(dev->mtu);
 476	if (mtu < IPV4_MIN_MTU)
 477		return skb;
 478
 479	isquery = type == IGMPV3_MODE_IS_INCLUDE ||
 480		  type == IGMPV3_MODE_IS_EXCLUDE;
 481	truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
 482		    type == IGMPV3_CHANGE_TO_EXCLUDE;
 483
 484	stotal = scount = 0;
 485
 486	psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
 487
 488	if (!*psf_list)
 489		goto empty_source;
 490
 491	pih = skb ? igmpv3_report_hdr(skb) : NULL;
 492
 493	/* EX and TO_EX get a fresh packet, if needed */
 494	if (truncate) {
 495		if (pih && pih->ngrec &&
 496		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
 497			if (skb)
 498				igmpv3_sendpack(skb);
 499			skb = igmpv3_newpack(dev, mtu);
 500		}
 501	}
 502	first = 1;
 503	psf_prev = NULL;
 504	for (psf = *psf_list; psf; psf = psf_next) {
 505		__be32 *psrc;
 506
 507		psf_next = psf->sf_next;
 508
 509		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
 510			psf_prev = psf;
 511			continue;
 512		}
 513
 514		/* Based on RFC3376 5.1. Should not send source-list change
 515		 * records when there is a filter mode change.
 516		 */
 517		if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) ||
 518		     (!gdeleted && pmc->crcount)) &&
 519		    (type == IGMPV3_ALLOW_NEW_SOURCES ||
 520		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount)
 521			goto decrease_sf_crcount;
 522
 523		/* clear marks on query responses */
 524		if (isquery)
 525			psf->sf_gsresp = 0;
 526
 527		if (AVAILABLE(skb) < sizeof(__be32) +
 528		    first*sizeof(struct igmpv3_grec)) {
 529			if (truncate && !first)
 530				break;	 /* truncate these */
 531			if (pgr)
 532				pgr->grec_nsrcs = htons(scount);
 533			if (skb)
 534				igmpv3_sendpack(skb);
 535			skb = igmpv3_newpack(dev, mtu);
 536			first = 1;
 537			scount = 0;
 538		}
 539		if (first) {
 540			skb = add_grhead(skb, pmc, type, &pgr, mtu);
 541			first = 0;
 542		}
 543		if (!skb)
 544			return NULL;
 545		psrc = skb_put(skb, sizeof(__be32));
 546		*psrc = psf->sf_inaddr;
 547		scount++; stotal++;
 548		if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
 549		     type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
 550decrease_sf_crcount:
 551			psf->sf_crcount--;
 552			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
 553				if (psf_prev)
 554					psf_prev->sf_next = psf->sf_next;
 555				else
 556					*psf_list = psf->sf_next;
 557				kfree(psf);
 558				continue;
 559			}
 560		}
 561		psf_prev = psf;
 562	}
 563
 564empty_source:
 565	if (!stotal) {
 566		if (type == IGMPV3_ALLOW_NEW_SOURCES ||
 567		    type == IGMPV3_BLOCK_OLD_SOURCES)
 568			return skb;
 569		if (pmc->crcount || isquery) {
 570			/* make sure we have room for group header */
 571			if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) {
 572				igmpv3_sendpack(skb);
 573				skb = NULL; /* add_grhead will get a new one */
 574			}
 575			skb = add_grhead(skb, pmc, type, &pgr, mtu);
 576		}
 577	}
 578	if (pgr)
 579		pgr->grec_nsrcs = htons(scount);
 580
 581	if (isquery)
 582		pmc->gsquery = 0;	/* clear query state on report */
 583	return skb;
 584}
 585
 586static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
 587{
 588	struct sk_buff *skb = NULL;
 589	struct net *net = dev_net(in_dev->dev);
 590	int type;
 591
 592	if (!pmc) {
 593		rcu_read_lock();
 594		for_each_pmc_rcu(in_dev, pmc) {
 595			if (pmc->multiaddr == IGMP_ALL_HOSTS)
 596				continue;
 597			if (ipv4_is_local_multicast(pmc->multiaddr) &&
 598			     !net->ipv4.sysctl_igmp_llm_reports)
 599				continue;
 600			spin_lock_bh(&pmc->lock);
 601			if (pmc->sfcount[MCAST_EXCLUDE])
 602				type = IGMPV3_MODE_IS_EXCLUDE;
 603			else
 604				type = IGMPV3_MODE_IS_INCLUDE;
 605			skb = add_grec(skb, pmc, type, 0, 0);
 606			spin_unlock_bh(&pmc->lock);
 607		}
 608		rcu_read_unlock();
 609	} else {
 610		spin_lock_bh(&pmc->lock);
 611		if (pmc->sfcount[MCAST_EXCLUDE])
 612			type = IGMPV3_MODE_IS_EXCLUDE;
 613		else
 614			type = IGMPV3_MODE_IS_INCLUDE;
 615		skb = add_grec(skb, pmc, type, 0, 0);
 616		spin_unlock_bh(&pmc->lock);
 617	}
 618	if (!skb)
 619		return 0;
 620	return igmpv3_sendpack(skb);
 621}
 622
 623/*
 624 * remove zero-count source records from a source filter list
 625 */
 626static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
 627{
 628	struct ip_sf_list *psf_prev, *psf_next, *psf;
 629
 630	psf_prev = NULL;
 631	for (psf = *ppsf; psf; psf = psf_next) {
 632		psf_next = psf->sf_next;
 633		if (psf->sf_crcount == 0) {
 634			if (psf_prev)
 635				psf_prev->sf_next = psf->sf_next;
 636			else
 637				*ppsf = psf->sf_next;
 638			kfree(psf);
 639		} else
 640			psf_prev = psf;
 641	}
 642}
 643
 644static void kfree_pmc(struct ip_mc_list *pmc)
 645{
 646	ip_sf_list_clear_all(pmc->sources);
 647	ip_sf_list_clear_all(pmc->tomb);
 648	kfree(pmc);
 649}
 650
 651static void igmpv3_send_cr(struct in_device *in_dev)
 652{
 653	struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
 654	struct sk_buff *skb = NULL;
 655	int type, dtype;
 656
 657	rcu_read_lock();
 658	spin_lock_bh(&in_dev->mc_tomb_lock);
 659
 660	/* deleted MCA's */
 661	pmc_prev = NULL;
 662	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) {
 663		pmc_next = pmc->next;
 664		if (pmc->sfmode == MCAST_INCLUDE) {
 665			type = IGMPV3_BLOCK_OLD_SOURCES;
 666			dtype = IGMPV3_BLOCK_OLD_SOURCES;
 667			skb = add_grec(skb, pmc, type, 1, 0);
 668			skb = add_grec(skb, pmc, dtype, 1, 1);
 669		}
 670		if (pmc->crcount) {
 671			if (pmc->sfmode == MCAST_EXCLUDE) {
 672				type = IGMPV3_CHANGE_TO_INCLUDE;
 673				skb = add_grec(skb, pmc, type, 1, 0);
 674			}
 675			pmc->crcount--;
 676			if (pmc->crcount == 0) {
 677				igmpv3_clear_zeros(&pmc->tomb);
 678				igmpv3_clear_zeros(&pmc->sources);
 679			}
 680		}
 681		if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
 682			if (pmc_prev)
 683				pmc_prev->next = pmc_next;
 684			else
 685				in_dev->mc_tomb = pmc_next;
 686			in_dev_put(pmc->interface);
 687			kfree_pmc(pmc);
 688		} else
 689			pmc_prev = pmc;
 690	}
 691	spin_unlock_bh(&in_dev->mc_tomb_lock);
 692
 693	/* change recs */
 694	for_each_pmc_rcu(in_dev, pmc) {
 695		spin_lock_bh(&pmc->lock);
 696		if (pmc->sfcount[MCAST_EXCLUDE]) {
 697			type = IGMPV3_BLOCK_OLD_SOURCES;
 698			dtype = IGMPV3_ALLOW_NEW_SOURCES;
 699		} else {
 700			type = IGMPV3_ALLOW_NEW_SOURCES;
 701			dtype = IGMPV3_BLOCK_OLD_SOURCES;
 702		}
 703		skb = add_grec(skb, pmc, type, 0, 0);
 704		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
 705
 706		/* filter mode changes */
 707		if (pmc->crcount) {
 708			if (pmc->sfmode == MCAST_EXCLUDE)
 709				type = IGMPV3_CHANGE_TO_EXCLUDE;
 710			else
 711				type = IGMPV3_CHANGE_TO_INCLUDE;
 712			skb = add_grec(skb, pmc, type, 0, 0);
 713			pmc->crcount--;
 714		}
 715		spin_unlock_bh(&pmc->lock);
 716	}
 717	rcu_read_unlock();
 718
 719	if (!skb)
 720		return;
 721	(void) igmpv3_sendpack(skb);
 722}
 723
 724static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
 725	int type)
 726{
 727	struct sk_buff *skb;
 728	struct iphdr *iph;
 729	struct igmphdr *ih;
 730	struct rtable *rt;
 731	struct net_device *dev = in_dev->dev;
 732	struct net *net = dev_net(dev);
 733	__be32	group = pmc ? pmc->multiaddr : 0;
 734	struct flowi4 fl4;
 735	__be32	dst;
 736	int hlen, tlen;
 737
 738	if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
 739		return igmpv3_send_report(in_dev, pmc);
 740
 741	if (ipv4_is_local_multicast(group) && !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
 809	igmpv3_send_cr(in_dev);
 810	if (in_dev->mr_ifc_count) {
 811		in_dev->mr_ifc_count--;
 
 
 
 
 
 
 812		igmp_ifc_start_timer(in_dev,
 813				     unsolicited_report_interval(in_dev));
 814	}
 815	in_dev_put(in_dev);
 816}
 817
 818static void igmp_ifc_event(struct in_device *in_dev)
 819{
 820	struct net *net = dev_net(in_dev->dev);
 821	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 822		return;
 823	in_dev->mr_ifc_count = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
 824	igmp_ifc_start_timer(in_dev, 1);
 825}
 826
 827
 828static void igmp_timer_expire(struct timer_list *t)
 829{
 830	struct ip_mc_list *im = from_timer(im, t, timer);
 831	struct in_device *in_dev = im->interface;
 832
 833	spin_lock(&im->lock);
 834	im->tm_running = 0;
 835
 836	if (im->unsolicit_count && --im->unsolicit_count)
 837		igmp_start_timer(im, unsolicited_report_interval(in_dev));
 838
 839	im->reporter = 1;
 840	spin_unlock(&im->lock);
 841
 842	if (IGMP_V1_SEEN(in_dev))
 843		igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
 844	else if (IGMP_V2_SEEN(in_dev))
 845		igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
 846	else
 847		igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
 848
 849	ip_ma_put(im);
 850}
 851
 852/* mark EXCLUDE-mode sources */
 853static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 854{
 855	struct ip_sf_list *psf;
 856	int i, scount;
 857
 858	scount = 0;
 859	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 860		if (scount == nsrcs)
 861			break;
 862		for (i = 0; i < nsrcs; i++) {
 863			/* skip inactive filters */
 864			if (psf->sf_count[MCAST_INCLUDE] ||
 865			    pmc->sfcount[MCAST_EXCLUDE] !=
 866			    psf->sf_count[MCAST_EXCLUDE])
 867				break;
 868			if (srcs[i] == psf->sf_inaddr) {
 869				scount++;
 870				break;
 871			}
 872		}
 873	}
 874	pmc->gsquery = 0;
 875	if (scount == nsrcs)	/* all sources excluded */
 876		return 0;
 877	return 1;
 878}
 879
 880static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 881{
 882	struct ip_sf_list *psf;
 883	int i, scount;
 884
 885	if (pmc->sfmode == MCAST_EXCLUDE)
 886		return igmp_xmarksources(pmc, nsrcs, srcs);
 887
 888	/* mark INCLUDE-mode sources */
 889	scount = 0;
 890	for (psf = pmc->sources; psf; psf = psf->sf_next) {
 891		if (scount == nsrcs)
 892			break;
 893		for (i = 0; i < nsrcs; i++)
 894			if (srcs[i] == psf->sf_inaddr) {
 895				psf->sf_gsresp = 1;
 896				scount++;
 897				break;
 898			}
 899	}
 900	if (!scount) {
 901		pmc->gsquery = 0;
 902		return 0;
 903	}
 904	pmc->gsquery = 1;
 905	return 1;
 906}
 907
 908/* return true if packet was dropped */
 909static bool igmp_heard_report(struct in_device *in_dev, __be32 group)
 910{
 911	struct ip_mc_list *im;
 912	struct net *net = dev_net(in_dev->dev);
 913
 914	/* Timers are only set for non-local groups */
 915
 916	if (group == IGMP_ALL_HOSTS)
 917		return false;
 918	if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
 
 919		return false;
 920
 921	rcu_read_lock();
 922	for_each_pmc_rcu(in_dev, im) {
 923		if (im->multiaddr == group) {
 924			igmp_stop_timer(im);
 925			break;
 926		}
 927	}
 928	rcu_read_unlock();
 929	return false;
 930}
 931
 932/* return true if packet was dropped */
 933static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
 934	int len)
 935{
 936	struct igmphdr 		*ih = igmp_hdr(skb);
 937	struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
 938	struct ip_mc_list	*im;
 939	__be32			group = ih->group;
 940	int			max_delay;
 941	int			mark = 0;
 942	struct net		*net = dev_net(in_dev->dev);
 943
 944
 945	if (len == 8) {
 946		if (ih->code == 0) {
 947			/* Alas, old v1 router presents here. */
 948
 949			max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 950			in_dev->mr_v1_seen = jiffies +
 951				(in_dev->mr_qrv * in_dev->mr_qi) +
 952				in_dev->mr_qri;
 953			group = 0;
 954		} else {
 955			/* v2 router present */
 956			max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
 957			in_dev->mr_v2_seen = jiffies +
 958				(in_dev->mr_qrv * in_dev->mr_qi) +
 959				in_dev->mr_qri;
 960		}
 961		/* cancel the interface change timer */
 962		in_dev->mr_ifc_count = 0;
 963		if (del_timer(&in_dev->mr_ifc_timer))
 964			__in_dev_put(in_dev);
 965		/* clear deleted report items */
 966		igmpv3_clear_delrec(in_dev);
 967	} else if (len < 12) {
 968		return true;	/* ignore bogus packet; freed by caller */
 969	} else if (IGMP_V1_SEEN(in_dev)) {
 970		/* This is a v3 query with v1 queriers present */
 971		max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 972		group = 0;
 973	} else if (IGMP_V2_SEEN(in_dev)) {
 974		/* this is a v3 query with v2 queriers present;
 975		 * Interpretation of the max_delay code is problematic here.
 976		 * A real v2 host would use ih_code directly, while v3 has a
 977		 * different encoding. We use the v3 encoding as more likely
 978		 * to be intended in a v3 query.
 979		 */
 980		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 981		if (!max_delay)
 982			max_delay = 1;	/* can't mod w/ 0 */
 983	} else { /* v3 */
 984		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
 985			return true;
 986
 987		ih3 = igmpv3_query_hdr(skb);
 988		if (ih3->nsrcs) {
 989			if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
 990					   + ntohs(ih3->nsrcs)*sizeof(__be32)))
 991				return true;
 992			ih3 = igmpv3_query_hdr(skb);
 993		}
 994
 995		max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 996		if (!max_delay)
 997			max_delay = 1;	/* can't mod w/ 0 */
 998		in_dev->mr_maxdelay = max_delay;
 999
1000		/* RFC3376, 4.1.6. QRV and 4.1.7. QQIC, when the most recently
1001		 * received value was zero, use the default or statically
1002		 * configured value.
1003		 */
1004		in_dev->mr_qrv = ih3->qrv ?: net->ipv4.sysctl_igmp_qrv;
1005		in_dev->mr_qi = IGMPV3_QQIC(ih3->qqic)*HZ ?: IGMP_QUERY_INTERVAL;
1006
1007		/* RFC3376, 8.3. Query Response Interval:
1008		 * The number of seconds represented by the [Query Response
1009		 * Interval] must be less than the [Query Interval].
1010		 */
1011		if (in_dev->mr_qri >= in_dev->mr_qi)
1012			in_dev->mr_qri = (in_dev->mr_qi/HZ - 1)*HZ;
1013
1014		if (!group) { /* general query */
1015			if (ih3->nsrcs)
1016				return true;	/* no sources allowed */
1017			igmp_gq_start_timer(in_dev);
1018			return false;
1019		}
1020		/* mark sources to include, if group & source-specific */
1021		mark = ih3->nsrcs != 0;
1022	}
1023
1024	/*
1025	 * - Start the timers in all of our membership records
1026	 *   that the query applies to for the interface on
1027	 *   which the query arrived excl. those that belong
1028	 *   to a "local" group (224.0.0.X)
1029	 * - For timers already running check if they need to
1030	 *   be reset.
1031	 * - Use the igmp->igmp_code field as the maximum
1032	 *   delay possible
1033	 */
1034	rcu_read_lock();
1035	for_each_pmc_rcu(in_dev, im) {
1036		int changed;
1037
1038		if (group && group != im->multiaddr)
1039			continue;
1040		if (im->multiaddr == IGMP_ALL_HOSTS)
1041			continue;
1042		if (ipv4_is_local_multicast(im->multiaddr) &&
1043		    !net->ipv4.sysctl_igmp_llm_reports)
1044			continue;
1045		spin_lock_bh(&im->lock);
1046		if (im->tm_running)
1047			im->gsquery = im->gsquery && mark;
1048		else
1049			im->gsquery = mark;
1050		changed = !im->gsquery ||
1051			igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
1052		spin_unlock_bh(&im->lock);
1053		if (changed)
1054			igmp_mod_timer(im, max_delay);
1055	}
1056	rcu_read_unlock();
1057	return false;
1058}
1059
1060/* called in rcu_read_lock() section */
1061int igmp_rcv(struct sk_buff *skb)
1062{
1063	/* This basically follows the spec line by line -- see RFC1112 */
1064	struct igmphdr *ih;
1065	struct net_device *dev = skb->dev;
1066	struct in_device *in_dev;
1067	int len = skb->len;
1068	bool dropped = true;
1069
1070	if (netif_is_l3_master(dev)) {
1071		dev = dev_get_by_index_rcu(dev_net(dev), IPCB(skb)->iif);
1072		if (!dev)
1073			goto drop;
1074	}
1075
1076	in_dev = __in_dev_get_rcu(dev);
1077	if (!in_dev)
1078		goto drop;
1079
1080	if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
1081		goto drop;
1082
1083	if (skb_checksum_simple_validate(skb))
1084		goto drop;
1085
1086	ih = igmp_hdr(skb);
1087	switch (ih->type) {
1088	case IGMP_HOST_MEMBERSHIP_QUERY:
1089		dropped = igmp_heard_query(in_dev, skb, len);
1090		break;
1091	case IGMP_HOST_MEMBERSHIP_REPORT:
1092	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1093		/* Is it our report looped back? */
1094		if (rt_is_output_route(skb_rtable(skb)))
1095			break;
1096		/* don't rely on MC router hearing unicast reports */
1097		if (skb->pkt_type == PACKET_MULTICAST ||
1098		    skb->pkt_type == PACKET_BROADCAST)
1099			dropped = igmp_heard_report(in_dev, ih->group);
1100		break;
1101	case IGMP_PIM:
1102#ifdef CONFIG_IP_PIMSM_V1
1103		return pim_rcv_v1(skb);
1104#endif
1105	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1106	case IGMP_DVMRP:
1107	case IGMP_TRACE:
1108	case IGMP_HOST_LEAVE_MESSAGE:
1109	case IGMP_MTRACE:
1110	case IGMP_MTRACE_RESP:
1111		break;
1112	default:
1113		break;
1114	}
1115
1116drop:
1117	if (dropped)
1118		kfree_skb(skb);
1119	else
1120		consume_skb(skb);
1121	return 0;
1122}
1123
1124#endif
1125
1126
1127/*
1128 *	Add a filter to a device
1129 */
1130
1131static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1132{
1133	char buf[MAX_ADDR_LEN];
1134	struct net_device *dev = in_dev->dev;
1135
1136	/* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1137	   We will get multicast token leakage, when IFF_MULTICAST
1138	   is changed. This check should be done in ndo_set_rx_mode
1139	   routine. Something sort of:
1140	   if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1141	   --ANK
1142	   */
1143	if (arp_mc_map(addr, buf, dev, 0) == 0)
1144		dev_mc_add(dev, buf);
1145}
1146
1147/*
1148 *	Remove a filter from a device
1149 */
1150
1151static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1152{
1153	char buf[MAX_ADDR_LEN];
1154	struct net_device *dev = in_dev->dev;
1155
1156	if (arp_mc_map(addr, buf, dev, 0) == 0)
1157		dev_mc_del(dev, buf);
1158}
1159
1160#ifdef CONFIG_IP_MULTICAST
1161/*
1162 * deleted ip_mc_list manipulation
1163 */
1164static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im,
1165			      gfp_t gfp)
1166{
1167	struct ip_mc_list *pmc;
1168	struct net *net = dev_net(in_dev->dev);
1169
1170	/* this is an "ip_mc_list" for convenience; only the fields below
1171	 * are actually used. In particular, the refcnt and users are not
1172	 * used for management of the delete list. Using the same structure
1173	 * for deleted items allows change reports to use common code with
1174	 * non-deleted or query-response MCA's.
1175	 */
1176	pmc = kzalloc(sizeof(*pmc), gfp);
1177	if (!pmc)
1178		return;
1179	spin_lock_init(&pmc->lock);
1180	spin_lock_bh(&im->lock);
1181	pmc->interface = im->interface;
1182	in_dev_hold(in_dev);
1183	pmc->multiaddr = im->multiaddr;
1184	pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1185	pmc->sfmode = im->sfmode;
1186	if (pmc->sfmode == MCAST_INCLUDE) {
1187		struct ip_sf_list *psf;
1188
1189		pmc->tomb = im->tomb;
1190		pmc->sources = im->sources;
1191		im->tomb = im->sources = NULL;
1192		for (psf = pmc->sources; psf; psf = psf->sf_next)
1193			psf->sf_crcount = pmc->crcount;
1194	}
1195	spin_unlock_bh(&im->lock);
1196
1197	spin_lock_bh(&in_dev->mc_tomb_lock);
1198	pmc->next = in_dev->mc_tomb;
1199	in_dev->mc_tomb = pmc;
1200	spin_unlock_bh(&in_dev->mc_tomb_lock);
1201}
1202
1203/*
1204 * restore ip_mc_list deleted records
1205 */
1206static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1207{
1208	struct ip_mc_list *pmc, *pmc_prev;
1209	struct ip_sf_list *psf;
1210	struct net *net = dev_net(in_dev->dev);
1211	__be32 multiaddr = im->multiaddr;
1212
1213	spin_lock_bh(&in_dev->mc_tomb_lock);
1214	pmc_prev = NULL;
1215	for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) {
1216		if (pmc->multiaddr == multiaddr)
1217			break;
1218		pmc_prev = pmc;
1219	}
1220	if (pmc) {
1221		if (pmc_prev)
1222			pmc_prev->next = pmc->next;
1223		else
1224			in_dev->mc_tomb = pmc->next;
1225	}
1226	spin_unlock_bh(&in_dev->mc_tomb_lock);
1227
1228	spin_lock_bh(&im->lock);
1229	if (pmc) {
1230		im->interface = pmc->interface;
1231		if (im->sfmode == MCAST_INCLUDE) {
1232			swap(im->tomb, pmc->tomb);
1233			swap(im->sources, pmc->sources);
1234			for (psf = im->sources; psf; psf = psf->sf_next)
1235				psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
 
1236		} else {
1237			im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
 
1238		}
1239		in_dev_put(pmc->interface);
1240		kfree_pmc(pmc);
1241	}
1242	spin_unlock_bh(&im->lock);
1243}
1244
1245/*
1246 * flush ip_mc_list deleted records
1247 */
1248static void igmpv3_clear_delrec(struct in_device *in_dev)
1249{
1250	struct ip_mc_list *pmc, *nextpmc;
1251
1252	spin_lock_bh(&in_dev->mc_tomb_lock);
1253	pmc = in_dev->mc_tomb;
1254	in_dev->mc_tomb = NULL;
1255	spin_unlock_bh(&in_dev->mc_tomb_lock);
1256
1257	for (; pmc; pmc = nextpmc) {
1258		nextpmc = pmc->next;
1259		ip_mc_clear_src(pmc);
1260		in_dev_put(pmc->interface);
1261		kfree_pmc(pmc);
1262	}
1263	/* clear dead sources, too */
1264	rcu_read_lock();
1265	for_each_pmc_rcu(in_dev, pmc) {
1266		struct ip_sf_list *psf;
1267
1268		spin_lock_bh(&pmc->lock);
1269		psf = pmc->tomb;
1270		pmc->tomb = NULL;
1271		spin_unlock_bh(&pmc->lock);
1272		ip_sf_list_clear_all(psf);
1273	}
1274	rcu_read_unlock();
1275}
1276#endif
1277
1278static void __igmp_group_dropped(struct ip_mc_list *im, gfp_t gfp)
1279{
1280	struct in_device *in_dev = im->interface;
1281#ifdef CONFIG_IP_MULTICAST
1282	struct net *net = dev_net(in_dev->dev);
1283	int reporter;
1284#endif
1285
1286	if (im->loaded) {
1287		im->loaded = 0;
1288		ip_mc_filter_del(in_dev, im->multiaddr);
1289	}
1290
1291#ifdef CONFIG_IP_MULTICAST
1292	if (im->multiaddr == IGMP_ALL_HOSTS)
1293		return;
1294	if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
 
1295		return;
1296
1297	reporter = im->reporter;
1298	igmp_stop_timer(im);
1299
1300	if (!in_dev->dead) {
1301		if (IGMP_V1_SEEN(in_dev))
1302			return;
1303		if (IGMP_V2_SEEN(in_dev)) {
1304			if (reporter)
1305				igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1306			return;
1307		}
1308		/* IGMPv3 */
1309		igmpv3_add_delrec(in_dev, im, gfp);
1310
1311		igmp_ifc_event(in_dev);
1312	}
1313#endif
1314}
1315
1316static void igmp_group_dropped(struct ip_mc_list *im)
1317{
1318	__igmp_group_dropped(im, GFP_KERNEL);
1319}
1320
1321static void igmp_group_added(struct ip_mc_list *im)
1322{
1323	struct in_device *in_dev = im->interface;
1324#ifdef CONFIG_IP_MULTICAST
1325	struct net *net = dev_net(in_dev->dev);
1326#endif
1327
1328	if (im->loaded == 0) {
1329		im->loaded = 1;
1330		ip_mc_filter_add(in_dev, im->multiaddr);
1331	}
1332
1333#ifdef CONFIG_IP_MULTICAST
1334	if (im->multiaddr == IGMP_ALL_HOSTS)
1335		return;
1336	if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
 
1337		return;
1338
1339	if (in_dev->dead)
1340		return;
1341
1342	im->unsolicit_count = net->ipv4.sysctl_igmp_qrv;
1343	if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1344		spin_lock_bh(&im->lock);
1345		igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY);
1346		spin_unlock_bh(&im->lock);
1347		return;
1348	}
1349	/* else, v3 */
1350
1351	/* Based on RFC3376 5.1, for newly added INCLUDE SSM, we should
1352	 * not send filter-mode change record as the mode should be from
1353	 * IN() to IN(A).
1354	 */
1355	if (im->sfmode == MCAST_EXCLUDE)
1356		im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1357
1358	igmp_ifc_event(in_dev);
1359#endif
1360}
1361
1362
1363/*
1364 *	Multicast list managers
1365 */
1366
1367static u32 ip_mc_hash(const struct ip_mc_list *im)
1368{
1369	return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
1370}
1371
1372static void ip_mc_hash_add(struct in_device *in_dev,
1373			   struct ip_mc_list *im)
1374{
1375	struct ip_mc_list __rcu **mc_hash;
1376	u32 hash;
1377
1378	mc_hash = rtnl_dereference(in_dev->mc_hash);
1379	if (mc_hash) {
1380		hash = ip_mc_hash(im);
1381		im->next_hash = mc_hash[hash];
1382		rcu_assign_pointer(mc_hash[hash], im);
1383		return;
1384	}
1385
1386	/* do not use a hash table for small number of items */
1387	if (in_dev->mc_count < 4)
1388		return;
1389
1390	mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
1391			  GFP_KERNEL);
1392	if (!mc_hash)
1393		return;
1394
1395	for_each_pmc_rtnl(in_dev, im) {
1396		hash = ip_mc_hash(im);
1397		im->next_hash = mc_hash[hash];
1398		RCU_INIT_POINTER(mc_hash[hash], im);
1399	}
1400
1401	rcu_assign_pointer(in_dev->mc_hash, mc_hash);
1402}
1403
1404static void ip_mc_hash_remove(struct in_device *in_dev,
1405			      struct ip_mc_list *im)
1406{
1407	struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
1408	struct ip_mc_list *aux;
1409
1410	if (!mc_hash)
1411		return;
1412	mc_hash += ip_mc_hash(im);
1413	while ((aux = rtnl_dereference(*mc_hash)) != im)
1414		mc_hash = &aux->next_hash;
1415	*mc_hash = im->next_hash;
1416}
1417
1418
1419/*
1420 *	A socket has joined a multicast group on device dev.
1421 */
1422static void ____ip_mc_inc_group(struct in_device *in_dev, __be32 addr,
1423				unsigned int mode, gfp_t gfp)
1424{
 
1425	struct ip_mc_list *im;
1426
1427	ASSERT_RTNL();
1428
1429	for_each_pmc_rtnl(in_dev, im) {
1430		if (im->multiaddr == addr) {
1431			im->users++;
1432			ip_mc_add_src(in_dev, &addr, mode, 0, NULL, 0);
1433			goto out;
 
 
 
 
1434		}
 
 
 
 
 
 
 
 
 
 
 
1435	}
1436
1437	im = kzalloc(sizeof(*im), gfp);
1438	if (!im)
1439		goto out;
1440
1441	im->users = 1;
1442	im->interface = in_dev;
1443	in_dev_hold(in_dev);
1444	im->multiaddr = addr;
1445	/* initial mode is (EX, empty) */
1446	im->sfmode = mode;
1447	im->sfcount[mode] = 1;
1448	refcount_set(&im->refcnt, 1);
1449	spin_lock_init(&im->lock);
1450#ifdef CONFIG_IP_MULTICAST
1451	timer_setup(&im->timer, igmp_timer_expire, 0);
1452#endif
1453
1454	im->next_rcu = in_dev->mc_list;
1455	in_dev->mc_count++;
1456	rcu_assign_pointer(in_dev->mc_list, im);
1457
1458	ip_mc_hash_add(in_dev, im);
1459
1460#ifdef CONFIG_IP_MULTICAST
1461	igmpv3_del_delrec(in_dev, im);
1462#endif
1463	igmp_group_added(im);
1464	if (!in_dev->dead)
1465		ip_rt_multicast_event(in_dev);
1466out:
1467	return;
1468}
1469
1470void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr, gfp_t gfp)
1471{
1472	____ip_mc_inc_group(in_dev, addr, MCAST_EXCLUDE, gfp);
1473}
1474EXPORT_SYMBOL(__ip_mc_inc_group);
1475
1476void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1477{
1478	__ip_mc_inc_group(in_dev, addr, GFP_KERNEL);
1479}
1480EXPORT_SYMBOL(ip_mc_inc_group);
1481
1482static int ip_mc_check_iphdr(struct sk_buff *skb)
1483{
1484	const struct iphdr *iph;
1485	unsigned int len;
1486	unsigned int offset = skb_network_offset(skb) + sizeof(*iph);
1487
1488	if (!pskb_may_pull(skb, offset))
1489		return -EINVAL;
1490
1491	iph = ip_hdr(skb);
1492
1493	if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph))
1494		return -EINVAL;
1495
1496	offset += ip_hdrlen(skb) - sizeof(*iph);
1497
1498	if (!pskb_may_pull(skb, offset))
1499		return -EINVAL;
1500
1501	iph = ip_hdr(skb);
1502
1503	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1504		return -EINVAL;
1505
1506	len = skb_network_offset(skb) + ntohs(iph->tot_len);
1507	if (skb->len < len || len < offset)
1508		return -EINVAL;
1509
1510	skb_set_transport_header(skb, offset);
1511
1512	return 0;
1513}
1514
1515static int ip_mc_check_igmp_reportv3(struct sk_buff *skb)
1516{
1517	unsigned int len = skb_transport_offset(skb);
1518
1519	len += sizeof(struct igmpv3_report);
1520
1521	return ip_mc_may_pull(skb, len) ? 0 : -EINVAL;
1522}
1523
1524static int ip_mc_check_igmp_query(struct sk_buff *skb)
1525{
1526	unsigned int transport_len = ip_transport_len(skb);
1527	unsigned int len;
1528
1529	/* IGMPv{1,2}? */
1530	if (transport_len != sizeof(struct igmphdr)) {
1531		/* or IGMPv3? */
1532		if (transport_len < sizeof(struct igmpv3_query))
1533			return -EINVAL;
1534
1535		len = skb_transport_offset(skb) + sizeof(struct igmpv3_query);
1536		if (!ip_mc_may_pull(skb, len))
1537			return -EINVAL;
1538	}
1539
1540	/* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1541	 * all-systems destination addresses (224.0.0.1) for general queries
1542	 */
1543	if (!igmp_hdr(skb)->group &&
1544	    ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP))
1545		return -EINVAL;
1546
1547	return 0;
1548}
1549
1550static int ip_mc_check_igmp_msg(struct sk_buff *skb)
1551{
1552	switch (igmp_hdr(skb)->type) {
1553	case IGMP_HOST_LEAVE_MESSAGE:
1554	case IGMP_HOST_MEMBERSHIP_REPORT:
1555	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1556		return 0;
1557	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1558		return ip_mc_check_igmp_reportv3(skb);
1559	case IGMP_HOST_MEMBERSHIP_QUERY:
1560		return ip_mc_check_igmp_query(skb);
1561	default:
1562		return -ENOMSG;
1563	}
1564}
1565
1566static inline __sum16 ip_mc_validate_checksum(struct sk_buff *skb)
1567{
1568	return skb_checksum_simple_validate(skb);
1569}
1570
1571static int ip_mc_check_igmp_csum(struct sk_buff *skb)
1572{
1573	unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr);
1574	unsigned int transport_len = ip_transport_len(skb);
1575	struct sk_buff *skb_chk;
1576
1577	if (!ip_mc_may_pull(skb, len))
1578		return -EINVAL;
1579
1580	skb_chk = skb_checksum_trimmed(skb, transport_len,
1581				       ip_mc_validate_checksum);
1582	if (!skb_chk)
1583		return -EINVAL;
1584
1585	if (skb_chk != skb)
1586		kfree_skb(skb_chk);
1587
1588	return 0;
1589}
1590
1591/**
1592 * ip_mc_check_igmp - checks whether this is a sane IGMP packet
1593 * @skb: the skb to validate
1594 *
1595 * Checks whether an IPv4 packet is a valid IGMP packet. If so sets
1596 * skb transport header accordingly and returns zero.
1597 *
1598 * -EINVAL: A broken packet was detected, i.e. it violates some internet
1599 *  standard
1600 * -ENOMSG: IP header validation succeeded but it is not an IGMP packet.
1601 * -ENOMEM: A memory allocation failure happened.
1602 *
1603 * Caller needs to set the skb network header and free any returned skb if it
1604 * differs from the provided skb.
1605 */
1606int ip_mc_check_igmp(struct sk_buff *skb)
1607{
1608	int ret = ip_mc_check_iphdr(skb);
1609
1610	if (ret < 0)
1611		return ret;
1612
1613	if (ip_hdr(skb)->protocol != IPPROTO_IGMP)
1614		return -ENOMSG;
1615
1616	ret = ip_mc_check_igmp_csum(skb);
1617	if (ret < 0)
1618		return ret;
1619
1620	return ip_mc_check_igmp_msg(skb);
1621}
1622EXPORT_SYMBOL(ip_mc_check_igmp);
1623
1624/*
1625 *	Resend IGMP JOIN report; used by netdev notifier.
1626 */
1627static void ip_mc_rejoin_groups(struct in_device *in_dev)
1628{
1629#ifdef CONFIG_IP_MULTICAST
1630	struct ip_mc_list *im;
1631	int type;
1632	struct net *net = dev_net(in_dev->dev);
1633
1634	ASSERT_RTNL();
1635
1636	for_each_pmc_rtnl(in_dev, im) {
1637		if (im->multiaddr == IGMP_ALL_HOSTS)
1638			continue;
1639		if (ipv4_is_local_multicast(im->multiaddr) &&
1640		    !net->ipv4.sysctl_igmp_llm_reports)
1641			continue;
1642
1643		/* a failover is happening and switches
1644		 * must be notified immediately
1645		 */
1646		if (IGMP_V1_SEEN(in_dev))
1647			type = IGMP_HOST_MEMBERSHIP_REPORT;
1648		else if (IGMP_V2_SEEN(in_dev))
1649			type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1650		else
1651			type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1652		igmp_send_report(in_dev, im, type);
1653	}
1654#endif
1655}
1656
1657/*
1658 *	A socket has left a multicast group on device dev
1659 */
1660
1661void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp)
1662{
1663	struct ip_mc_list *i;
1664	struct ip_mc_list __rcu **ip;
1665
1666	ASSERT_RTNL();
1667
1668	for (ip = &in_dev->mc_list;
1669	     (i = rtnl_dereference(*ip)) != NULL;
1670	     ip = &i->next_rcu) {
1671		if (i->multiaddr == addr) {
1672			if (--i->users == 0) {
1673				ip_mc_hash_remove(in_dev, i);
1674				*ip = i->next_rcu;
1675				in_dev->mc_count--;
1676				__igmp_group_dropped(i, gfp);
1677				ip_mc_clear_src(i);
1678
1679				if (!in_dev->dead)
1680					ip_rt_multicast_event(in_dev);
1681
1682				ip_ma_put(i);
1683				return;
1684			}
1685			break;
1686		}
1687	}
1688}
1689EXPORT_SYMBOL(__ip_mc_dec_group);
1690
1691/* Device changing type */
1692
1693void ip_mc_unmap(struct in_device *in_dev)
1694{
1695	struct ip_mc_list *pmc;
1696
1697	ASSERT_RTNL();
1698
1699	for_each_pmc_rtnl(in_dev, pmc)
1700		igmp_group_dropped(pmc);
1701}
1702
1703void ip_mc_remap(struct in_device *in_dev)
1704{
1705	struct ip_mc_list *pmc;
1706
1707	ASSERT_RTNL();
1708
1709	for_each_pmc_rtnl(in_dev, pmc) {
1710#ifdef CONFIG_IP_MULTICAST
1711		igmpv3_del_delrec(in_dev, pmc);
1712#endif
1713		igmp_group_added(pmc);
1714	}
1715}
1716
1717/* Device going down */
1718
1719void ip_mc_down(struct in_device *in_dev)
1720{
1721	struct ip_mc_list *pmc;
1722
1723	ASSERT_RTNL();
1724
1725	for_each_pmc_rtnl(in_dev, pmc)
1726		igmp_group_dropped(pmc);
1727
1728#ifdef CONFIG_IP_MULTICAST
1729	in_dev->mr_ifc_count = 0;
1730	if (del_timer(&in_dev->mr_ifc_timer))
1731		__in_dev_put(in_dev);
1732	in_dev->mr_gq_running = 0;
1733	if (del_timer(&in_dev->mr_gq_timer))
1734		__in_dev_put(in_dev);
1735#endif
1736
1737	ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1738}
1739
1740#ifdef CONFIG_IP_MULTICAST
1741static void ip_mc_reset(struct in_device *in_dev)
1742{
1743	struct net *net = dev_net(in_dev->dev);
1744
1745	in_dev->mr_qi = IGMP_QUERY_INTERVAL;
1746	in_dev->mr_qri = IGMP_QUERY_RESPONSE_INTERVAL;
1747	in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1748}
1749#else
1750static void ip_mc_reset(struct in_device *in_dev)
1751{
1752}
1753#endif
1754
1755void ip_mc_init_dev(struct in_device *in_dev)
1756{
1757	ASSERT_RTNL();
1758
1759#ifdef CONFIG_IP_MULTICAST
1760	timer_setup(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 0);
1761	timer_setup(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 0);
1762#endif
1763	ip_mc_reset(in_dev);
1764
1765	spin_lock_init(&in_dev->mc_tomb_lock);
1766}
1767
1768/* Device going up */
1769
1770void ip_mc_up(struct in_device *in_dev)
1771{
1772	struct ip_mc_list *pmc;
1773
1774	ASSERT_RTNL();
1775
1776	ip_mc_reset(in_dev);
1777	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1778
1779	for_each_pmc_rtnl(in_dev, pmc) {
1780#ifdef CONFIG_IP_MULTICAST
1781		igmpv3_del_delrec(in_dev, pmc);
1782#endif
1783		igmp_group_added(pmc);
1784	}
1785}
1786
1787/*
1788 *	Device is about to be destroyed: clean up.
1789 */
1790
1791void ip_mc_destroy_dev(struct in_device *in_dev)
1792{
1793	struct ip_mc_list *i;
1794
1795	ASSERT_RTNL();
1796
1797	/* Deactivate timers */
1798	ip_mc_down(in_dev);
1799#ifdef CONFIG_IP_MULTICAST
1800	igmpv3_clear_delrec(in_dev);
1801#endif
1802
1803	while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1804		in_dev->mc_list = i->next_rcu;
1805		in_dev->mc_count--;
 
1806		ip_ma_put(i);
1807	}
1808}
1809
1810/* RTNL is locked */
1811static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1812{
1813	struct net_device *dev = NULL;
1814	struct in_device *idev = NULL;
1815
1816	if (imr->imr_ifindex) {
1817		idev = inetdev_by_index(net, imr->imr_ifindex);
1818		return idev;
1819	}
1820	if (imr->imr_address.s_addr) {
1821		dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1822		if (!dev)
1823			return NULL;
1824	}
1825
1826	if (!dev) {
1827		struct rtable *rt = ip_route_output(net,
1828						    imr->imr_multiaddr.s_addr,
1829						    0, 0, 0);
 
1830		if (!IS_ERR(rt)) {
1831			dev = rt->dst.dev;
1832			ip_rt_put(rt);
1833		}
1834	}
1835	if (dev) {
1836		imr->imr_ifindex = dev->ifindex;
1837		idev = __in_dev_get_rtnl(dev);
1838	}
1839	return idev;
1840}
1841
1842/*
1843 *	Join a socket to a group
1844 */
1845
1846static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1847	__be32 *psfsrc)
1848{
1849	struct ip_sf_list *psf, *psf_prev;
1850	int rv = 0;
1851
1852	psf_prev = NULL;
1853	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1854		if (psf->sf_inaddr == *psfsrc)
1855			break;
1856		psf_prev = psf;
1857	}
1858	if (!psf || psf->sf_count[sfmode] == 0) {
1859		/* source filter not found, or count wrong =>  bug */
1860		return -ESRCH;
1861	}
1862	psf->sf_count[sfmode]--;
1863	if (psf->sf_count[sfmode] == 0) {
1864		ip_rt_multicast_event(pmc->interface);
1865	}
1866	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1867#ifdef CONFIG_IP_MULTICAST
1868		struct in_device *in_dev = pmc->interface;
1869		struct net *net = dev_net(in_dev->dev);
1870#endif
1871
1872		/* no more filters for this source */
1873		if (psf_prev)
1874			psf_prev->sf_next = psf->sf_next;
1875		else
1876			pmc->sources = psf->sf_next;
1877#ifdef CONFIG_IP_MULTICAST
1878		if (psf->sf_oldin &&
1879		    !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1880			psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1881			psf->sf_next = pmc->tomb;
1882			pmc->tomb = psf;
1883			rv = 1;
1884		} else
1885#endif
1886			kfree(psf);
1887	}
1888	return rv;
1889}
1890
1891#ifndef CONFIG_IP_MULTICAST
1892#define igmp_ifc_event(x)	do { } while (0)
1893#endif
1894
1895static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1896			 int sfcount, __be32 *psfsrc, int delta)
1897{
1898	struct ip_mc_list *pmc;
1899	int	changerec = 0;
1900	int	i, err;
1901
1902	if (!in_dev)
1903		return -ENODEV;
1904	rcu_read_lock();
1905	for_each_pmc_rcu(in_dev, pmc) {
1906		if (*pmca == pmc->multiaddr)
1907			break;
1908	}
1909	if (!pmc) {
1910		/* MCA not found?? bug */
1911		rcu_read_unlock();
1912		return -ESRCH;
1913	}
1914	spin_lock_bh(&pmc->lock);
1915	rcu_read_unlock();
1916#ifdef CONFIG_IP_MULTICAST
1917	sf_markstate(pmc);
1918#endif
1919	if (!delta) {
1920		err = -EINVAL;
1921		if (!pmc->sfcount[sfmode])
1922			goto out_unlock;
1923		pmc->sfcount[sfmode]--;
1924	}
1925	err = 0;
1926	for (i = 0; i < sfcount; i++) {
1927		int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1928
1929		changerec |= rv > 0;
1930		if (!err && rv < 0)
1931			err = rv;
1932	}
1933	if (pmc->sfmode == MCAST_EXCLUDE &&
1934	    pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1935	    pmc->sfcount[MCAST_INCLUDE]) {
1936#ifdef CONFIG_IP_MULTICAST
1937		struct ip_sf_list *psf;
1938		struct net *net = dev_net(in_dev->dev);
1939#endif
1940
1941		/* filter mode change */
1942		pmc->sfmode = MCAST_INCLUDE;
1943#ifdef CONFIG_IP_MULTICAST
1944		pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1945		in_dev->mr_ifc_count = pmc->crcount;
1946		for (psf = pmc->sources; psf; psf = psf->sf_next)
1947			psf->sf_crcount = 0;
1948		igmp_ifc_event(pmc->interface);
1949	} else if (sf_setstate(pmc) || changerec) {
1950		igmp_ifc_event(pmc->interface);
1951#endif
1952	}
1953out_unlock:
1954	spin_unlock_bh(&pmc->lock);
1955	return err;
1956}
1957
1958/*
1959 * Add multicast single-source filter to the interface list
1960 */
1961static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1962	__be32 *psfsrc)
1963{
1964	struct ip_sf_list *psf, *psf_prev;
1965
1966	psf_prev = NULL;
1967	for (psf = pmc->sources; psf; psf = psf->sf_next) {
1968		if (psf->sf_inaddr == *psfsrc)
1969			break;
1970		psf_prev = psf;
1971	}
1972	if (!psf) {
1973		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1974		if (!psf)
1975			return -ENOBUFS;
1976		psf->sf_inaddr = *psfsrc;
1977		if (psf_prev) {
1978			psf_prev->sf_next = psf;
1979		} else
1980			pmc->sources = psf;
1981	}
1982	psf->sf_count[sfmode]++;
1983	if (psf->sf_count[sfmode] == 1) {
1984		ip_rt_multicast_event(pmc->interface);
1985	}
1986	return 0;
1987}
1988
1989#ifdef CONFIG_IP_MULTICAST
1990static void sf_markstate(struct ip_mc_list *pmc)
1991{
1992	struct ip_sf_list *psf;
1993	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1994
1995	for (psf = pmc->sources; psf; psf = psf->sf_next)
1996		if (pmc->sfcount[MCAST_EXCLUDE]) {
1997			psf->sf_oldin = mca_xcount ==
1998				psf->sf_count[MCAST_EXCLUDE] &&
1999				!psf->sf_count[MCAST_INCLUDE];
2000		} else
2001			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2002}
2003
2004static int sf_setstate(struct ip_mc_list *pmc)
2005{
2006	struct ip_sf_list *psf, *dpsf;
2007	int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
2008	int qrv = pmc->interface->mr_qrv;
2009	int new_in, rv;
2010
2011	rv = 0;
2012	for (psf = pmc->sources; psf; psf = psf->sf_next) {
2013		if (pmc->sfcount[MCAST_EXCLUDE]) {
2014			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2015				!psf->sf_count[MCAST_INCLUDE];
2016		} else
2017			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2018		if (new_in) {
2019			if (!psf->sf_oldin) {
2020				struct ip_sf_list *prev = NULL;
2021
2022				for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) {
2023					if (dpsf->sf_inaddr == psf->sf_inaddr)
2024						break;
2025					prev = dpsf;
2026				}
2027				if (dpsf) {
2028					if (prev)
2029						prev->sf_next = dpsf->sf_next;
2030					else
2031						pmc->tomb = dpsf->sf_next;
2032					kfree(dpsf);
2033				}
2034				psf->sf_crcount = qrv;
2035				rv++;
2036			}
2037		} else if (psf->sf_oldin) {
2038
2039			psf->sf_crcount = 0;
2040			/*
2041			 * add or update "delete" records if an active filter
2042			 * is now inactive
2043			 */
2044			for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next)
2045				if (dpsf->sf_inaddr == psf->sf_inaddr)
2046					break;
2047			if (!dpsf) {
2048				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
2049				if (!dpsf)
2050					continue;
2051				*dpsf = *psf;
2052				/* pmc->lock held by callers */
2053				dpsf->sf_next = pmc->tomb;
2054				pmc->tomb = dpsf;
2055			}
2056			dpsf->sf_crcount = qrv;
2057			rv++;
2058		}
2059	}
2060	return rv;
2061}
2062#endif
2063
2064/*
2065 * Add multicast source filter list to the interface list
2066 */
2067static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
2068			 int sfcount, __be32 *psfsrc, int delta)
2069{
2070	struct ip_mc_list *pmc;
2071	int	isexclude;
2072	int	i, err;
2073
2074	if (!in_dev)
2075		return -ENODEV;
2076	rcu_read_lock();
2077	for_each_pmc_rcu(in_dev, pmc) {
2078		if (*pmca == pmc->multiaddr)
2079			break;
2080	}
2081	if (!pmc) {
2082		/* MCA not found?? bug */
2083		rcu_read_unlock();
2084		return -ESRCH;
2085	}
2086	spin_lock_bh(&pmc->lock);
2087	rcu_read_unlock();
2088
2089#ifdef CONFIG_IP_MULTICAST
2090	sf_markstate(pmc);
2091#endif
2092	isexclude = pmc->sfmode == MCAST_EXCLUDE;
2093	if (!delta)
2094		pmc->sfcount[sfmode]++;
2095	err = 0;
2096	for (i = 0; i < sfcount; i++) {
2097		err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2098		if (err)
2099			break;
2100	}
2101	if (err) {
2102		int j;
2103
2104		if (!delta)
2105			pmc->sfcount[sfmode]--;
2106		for (j = 0; j < i; j++)
2107			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2108	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
2109#ifdef CONFIG_IP_MULTICAST
2110		struct ip_sf_list *psf;
2111		struct net *net = dev_net(pmc->interface->dev);
2112		in_dev = pmc->interface;
2113#endif
2114
2115		/* filter mode change */
2116		if (pmc->sfcount[MCAST_EXCLUDE])
2117			pmc->sfmode = MCAST_EXCLUDE;
2118		else if (pmc->sfcount[MCAST_INCLUDE])
2119			pmc->sfmode = MCAST_INCLUDE;
2120#ifdef CONFIG_IP_MULTICAST
2121		/* else no filters; keep old mode for reports */
2122
2123		pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
2124		in_dev->mr_ifc_count = pmc->crcount;
2125		for (psf = pmc->sources; psf; psf = psf->sf_next)
2126			psf->sf_crcount = 0;
2127		igmp_ifc_event(in_dev);
2128	} else if (sf_setstate(pmc)) {
2129		igmp_ifc_event(in_dev);
2130#endif
2131	}
2132	spin_unlock_bh(&pmc->lock);
2133	return err;
2134}
2135
2136static void ip_mc_clear_src(struct ip_mc_list *pmc)
2137{
2138	struct ip_sf_list *tomb, *sources;
2139
2140	spin_lock_bh(&pmc->lock);
2141	tomb = pmc->tomb;
2142	pmc->tomb = NULL;
2143	sources = pmc->sources;
2144	pmc->sources = NULL;
2145	pmc->sfmode = MCAST_EXCLUDE;
2146	pmc->sfcount[MCAST_INCLUDE] = 0;
2147	pmc->sfcount[MCAST_EXCLUDE] = 1;
2148	spin_unlock_bh(&pmc->lock);
2149
2150	ip_sf_list_clear_all(tomb);
2151	ip_sf_list_clear_all(sources);
2152}
2153
2154/* Join a multicast group
2155 */
2156static int __ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr,
2157			      unsigned int mode)
2158{
2159	__be32 addr = imr->imr_multiaddr.s_addr;
2160	struct ip_mc_socklist *iml, *i;
2161	struct in_device *in_dev;
2162	struct inet_sock *inet = inet_sk(sk);
2163	struct net *net = sock_net(sk);
2164	int ifindex;
2165	int count = 0;
2166	int err;
2167
2168	ASSERT_RTNL();
2169
2170	if (!ipv4_is_multicast(addr))
2171		return -EINVAL;
2172
2173	in_dev = ip_mc_find_dev(net, imr);
2174
2175	if (!in_dev) {
2176		err = -ENODEV;
2177		goto done;
2178	}
2179
2180	err = -EADDRINUSE;
2181	ifindex = imr->imr_ifindex;
2182	for_each_pmc_rtnl(inet, i) {
2183		if (i->multi.imr_multiaddr.s_addr == addr &&
2184		    i->multi.imr_ifindex == ifindex)
2185			goto done;
2186		count++;
2187	}
2188	err = -ENOBUFS;
2189	if (count >= net->ipv4.sysctl_igmp_max_memberships)
2190		goto done;
2191	iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
2192	if (!iml)
2193		goto done;
2194
2195	memcpy(&iml->multi, imr, sizeof(*imr));
2196	iml->next_rcu = inet->mc_list;
2197	iml->sflist = NULL;
2198	iml->sfmode = mode;
2199	rcu_assign_pointer(inet->mc_list, iml);
2200	____ip_mc_inc_group(in_dev, addr, mode, GFP_KERNEL);
2201	err = 0;
2202done:
2203	return err;
2204}
2205
2206/* Join ASM (Any-Source Multicast) group
2207 */
2208int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
2209{
2210	return __ip_mc_join_group(sk, imr, MCAST_EXCLUDE);
2211}
2212EXPORT_SYMBOL(ip_mc_join_group);
2213
2214/* Join SSM (Source-Specific Multicast) group
2215 */
2216int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr,
2217			 unsigned int mode)
2218{
2219	return __ip_mc_join_group(sk, imr, mode);
2220}
2221
2222static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
2223			   struct in_device *in_dev)
2224{
2225	struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
2226	int err;
2227
2228	if (!psf) {
2229		/* any-source empty exclude case */
2230		return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2231			iml->sfmode, 0, NULL, 0);
2232	}
2233	err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2234			iml->sfmode, psf->sl_count, psf->sl_addr, 0);
2235	RCU_INIT_POINTER(iml->sflist, NULL);
2236	/* decrease mem now to avoid the memleak warning */
2237	atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc);
2238	kfree_rcu(psf, rcu);
2239	return err;
2240}
2241
2242int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
2243{
2244	struct inet_sock *inet = inet_sk(sk);
2245	struct ip_mc_socklist *iml;
2246	struct ip_mc_socklist __rcu **imlp;
2247	struct in_device *in_dev;
2248	struct net *net = sock_net(sk);
2249	__be32 group = imr->imr_multiaddr.s_addr;
2250	u32 ifindex;
2251	int ret = -EADDRNOTAVAIL;
2252
2253	ASSERT_RTNL();
2254
2255	in_dev = ip_mc_find_dev(net, imr);
2256	if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) {
2257		ret = -ENODEV;
2258		goto out;
2259	}
2260	ifindex = imr->imr_ifindex;
2261	for (imlp = &inet->mc_list;
2262	     (iml = rtnl_dereference(*imlp)) != NULL;
2263	     imlp = &iml->next_rcu) {
2264		if (iml->multi.imr_multiaddr.s_addr != group)
2265			continue;
2266		if (ifindex) {
2267			if (iml->multi.imr_ifindex != ifindex)
2268				continue;
2269		} else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
2270				iml->multi.imr_address.s_addr)
2271			continue;
2272
2273		(void) ip_mc_leave_src(sk, iml, in_dev);
2274
2275		*imlp = iml->next_rcu;
2276
2277		if (in_dev)
2278			ip_mc_dec_group(in_dev, group);
2279
2280		/* decrease mem now to avoid the memleak warning */
2281		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2282		kfree_rcu(iml, rcu);
2283		return 0;
2284	}
2285out:
2286	return ret;
2287}
2288EXPORT_SYMBOL(ip_mc_leave_group);
2289
2290int ip_mc_source(int add, int omode, struct sock *sk, struct
2291	ip_mreq_source *mreqs, int ifindex)
2292{
2293	int err;
2294	struct ip_mreqn imr;
2295	__be32 addr = mreqs->imr_multiaddr;
2296	struct ip_mc_socklist *pmc;
2297	struct in_device *in_dev = NULL;
2298	struct inet_sock *inet = inet_sk(sk);
2299	struct ip_sf_socklist *psl;
2300	struct net *net = sock_net(sk);
2301	int leavegroup = 0;
2302	int i, j, rv;
2303
2304	if (!ipv4_is_multicast(addr))
2305		return -EINVAL;
2306
2307	ASSERT_RTNL();
2308
2309	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
2310	imr.imr_address.s_addr = mreqs->imr_interface;
2311	imr.imr_ifindex = ifindex;
2312	in_dev = ip_mc_find_dev(net, &imr);
2313
2314	if (!in_dev) {
2315		err = -ENODEV;
2316		goto done;
2317	}
2318	err = -EADDRNOTAVAIL;
2319
2320	for_each_pmc_rtnl(inet, pmc) {
2321		if ((pmc->multi.imr_multiaddr.s_addr ==
2322		     imr.imr_multiaddr.s_addr) &&
2323		    (pmc->multi.imr_ifindex == imr.imr_ifindex))
2324			break;
2325	}
2326	if (!pmc) {		/* must have a prior join */
2327		err = -EINVAL;
2328		goto done;
2329	}
2330	/* if a source filter was set, must be the same mode as before */
2331	if (pmc->sflist) {
2332		if (pmc->sfmode != omode) {
2333			err = -EINVAL;
2334			goto done;
2335		}
2336	} else if (pmc->sfmode != omode) {
2337		/* allow mode switches for empty-set filters */
2338		ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
2339		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
2340			NULL, 0);
2341		pmc->sfmode = omode;
2342	}
2343
2344	psl = rtnl_dereference(pmc->sflist);
2345	if (!add) {
2346		if (!psl)
2347			goto done;	/* err = -EADDRNOTAVAIL */
2348		rv = !0;
2349		for (i = 0; i < psl->sl_count; i++) {
2350			rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2351				sizeof(__be32));
2352			if (rv == 0)
2353				break;
2354		}
2355		if (rv)		/* source not found */
2356			goto done;	/* err = -EADDRNOTAVAIL */
2357
2358		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2359		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
2360			leavegroup = 1;
2361			goto done;
2362		}
2363
2364		/* update the interface filter */
2365		ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2366			&mreqs->imr_sourceaddr, 1);
2367
2368		for (j = i+1; j < psl->sl_count; j++)
2369			psl->sl_addr[j-1] = psl->sl_addr[j];
2370		psl->sl_count--;
2371		err = 0;
2372		goto done;
2373	}
2374	/* else, add a new source to the filter */
2375
2376	if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) {
2377		err = -ENOBUFS;
2378		goto done;
2379	}
2380	if (!psl || psl->sl_count == psl->sl_max) {
2381		struct ip_sf_socklist *newpsl;
2382		int count = IP_SFBLOCK;
2383
2384		if (psl)
2385			count += psl->sl_max;
2386		newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
 
2387		if (!newpsl) {
2388			err = -ENOBUFS;
2389			goto done;
2390		}
2391		newpsl->sl_max = count;
2392		newpsl->sl_count = count - IP_SFBLOCK;
2393		if (psl) {
2394			for (i = 0; i < psl->sl_count; i++)
2395				newpsl->sl_addr[i] = psl->sl_addr[i];
2396			/* decrease mem now to avoid the memleak warning */
2397			atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2398			kfree_rcu(psl, rcu);
2399		}
2400		rcu_assign_pointer(pmc->sflist, newpsl);
 
 
2401		psl = newpsl;
2402	}
2403	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
2404	for (i = 0; i < psl->sl_count; i++) {
2405		rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2406			sizeof(__be32));
2407		if (rv == 0)
2408			break;
2409	}
2410	if (rv == 0)		/* address already there is an error */
2411		goto done;
2412	for (j = psl->sl_count-1; j >= i; j--)
2413		psl->sl_addr[j+1] = psl->sl_addr[j];
2414	psl->sl_addr[i] = mreqs->imr_sourceaddr;
2415	psl->sl_count++;
2416	err = 0;
2417	/* update the interface list */
2418	ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2419		&mreqs->imr_sourceaddr, 1);
2420done:
2421	if (leavegroup)
2422		err = ip_mc_leave_group(sk, &imr);
2423	return err;
2424}
2425
2426int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2427{
2428	int err = 0;
2429	struct ip_mreqn	imr;
2430	__be32 addr = msf->imsf_multiaddr;
2431	struct ip_mc_socklist *pmc;
2432	struct in_device *in_dev;
2433	struct inet_sock *inet = inet_sk(sk);
2434	struct ip_sf_socklist *newpsl, *psl;
2435	struct net *net = sock_net(sk);
2436	int leavegroup = 0;
2437
2438	if (!ipv4_is_multicast(addr))
2439		return -EINVAL;
2440	if (msf->imsf_fmode != MCAST_INCLUDE &&
2441	    msf->imsf_fmode != MCAST_EXCLUDE)
2442		return -EINVAL;
2443
2444	ASSERT_RTNL();
2445
2446	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2447	imr.imr_address.s_addr = msf->imsf_interface;
2448	imr.imr_ifindex = ifindex;
2449	in_dev = ip_mc_find_dev(net, &imr);
2450
2451	if (!in_dev) {
2452		err = -ENODEV;
2453		goto done;
2454	}
2455
2456	/* special case - (INCLUDE, empty) == LEAVE_GROUP */
2457	if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2458		leavegroup = 1;
2459		goto done;
2460	}
2461
2462	for_each_pmc_rtnl(inet, pmc) {
2463		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2464		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2465			break;
2466	}
2467	if (!pmc) {		/* must have a prior join */
2468		err = -EINVAL;
2469		goto done;
2470	}
2471	if (msf->imsf_numsrc) {
2472		newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2473							   GFP_KERNEL);
 
2474		if (!newpsl) {
2475			err = -ENOBUFS;
2476			goto done;
2477		}
2478		newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2479		memcpy(newpsl->sl_addr, msf->imsf_slist,
2480			msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2481		err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2482			msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2483		if (err) {
2484			sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
 
 
2485			goto done;
2486		}
2487	} else {
2488		newpsl = NULL;
2489		(void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2490				     msf->imsf_fmode, 0, NULL, 0);
2491	}
2492	psl = rtnl_dereference(pmc->sflist);
2493	if (psl) {
2494		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2495			psl->sl_count, psl->sl_addr, 0);
2496		/* decrease mem now to avoid the memleak warning */
2497		atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2498		kfree_rcu(psl, rcu);
2499	} else
2500		(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2501			0, NULL, 0);
 
2502	rcu_assign_pointer(pmc->sflist, newpsl);
 
 
2503	pmc->sfmode = msf->imsf_fmode;
2504	err = 0;
2505done:
2506	if (leavegroup)
2507		err = ip_mc_leave_group(sk, &imr);
2508	return err;
2509}
2510
2511int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2512	struct ip_msfilter __user *optval, int __user *optlen)
2513{
2514	int err, len, count, copycount;
2515	struct ip_mreqn	imr;
2516	__be32 addr = msf->imsf_multiaddr;
2517	struct ip_mc_socklist *pmc;
2518	struct in_device *in_dev;
2519	struct inet_sock *inet = inet_sk(sk);
2520	struct ip_sf_socklist *psl;
2521	struct net *net = sock_net(sk);
2522
2523	ASSERT_RTNL();
2524
2525	if (!ipv4_is_multicast(addr))
2526		return -EINVAL;
2527
2528	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2529	imr.imr_address.s_addr = msf->imsf_interface;
2530	imr.imr_ifindex = 0;
2531	in_dev = ip_mc_find_dev(net, &imr);
2532
2533	if (!in_dev) {
2534		err = -ENODEV;
2535		goto done;
2536	}
2537	err = -EADDRNOTAVAIL;
2538
2539	for_each_pmc_rtnl(inet, pmc) {
2540		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2541		    pmc->multi.imr_ifindex == imr.imr_ifindex)
2542			break;
2543	}
2544	if (!pmc)		/* must have a prior join */
2545		goto done;
2546	msf->imsf_fmode = pmc->sfmode;
2547	psl = rtnl_dereference(pmc->sflist);
2548	if (!psl) {
2549		len = 0;
2550		count = 0;
2551	} else {
2552		count = psl->sl_count;
2553	}
2554	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2555	len = copycount * sizeof(psl->sl_addr[0]);
2556	msf->imsf_numsrc = count;
2557	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2558	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
 
2559		return -EFAULT;
2560	}
2561	if (len &&
2562	    copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
 
 
2563		return -EFAULT;
2564	return 0;
2565done:
2566	return err;
2567}
2568
2569int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2570	struct group_filter __user *optval, int __user *optlen)
2571{
2572	int err, i, count, copycount;
2573	struct sockaddr_in *psin;
2574	__be32 addr;
2575	struct ip_mc_socklist *pmc;
2576	struct inet_sock *inet = inet_sk(sk);
2577	struct ip_sf_socklist *psl;
2578
2579	ASSERT_RTNL();
2580
2581	psin = (struct sockaddr_in *)&gsf->gf_group;
2582	if (psin->sin_family != AF_INET)
2583		return -EINVAL;
2584	addr = psin->sin_addr.s_addr;
2585	if (!ipv4_is_multicast(addr))
2586		return -EINVAL;
2587
2588	err = -EADDRNOTAVAIL;
2589
2590	for_each_pmc_rtnl(inet, pmc) {
2591		if (pmc->multi.imr_multiaddr.s_addr == addr &&
2592		    pmc->multi.imr_ifindex == gsf->gf_interface)
2593			break;
2594	}
2595	if (!pmc)		/* must have a prior join */
2596		goto done;
2597	gsf->gf_fmode = pmc->sfmode;
2598	psl = rtnl_dereference(pmc->sflist);
2599	count = psl ? psl->sl_count : 0;
2600	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2601	gsf->gf_numsrc = count;
2602	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2603	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2604		return -EFAULT;
2605	}
2606	for (i = 0; i < copycount; i++) {
2607		struct sockaddr_storage ss;
2608
2609		psin = (struct sockaddr_in *)&ss;
2610		memset(&ss, 0, sizeof(ss));
2611		psin->sin_family = AF_INET;
2612		psin->sin_addr.s_addr = psl->sl_addr[i];
2613		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
 
2614			return -EFAULT;
 
2615	}
2616	return 0;
2617done:
2618	return err;
2619}
2620
2621/*
2622 * check if a multicast source filter allows delivery for a given <src,dst,intf>
2623 */
2624int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr,
2625		   int dif, int sdif)
2626{
2627	struct inet_sock *inet = inet_sk(sk);
2628	struct ip_mc_socklist *pmc;
2629	struct ip_sf_socklist *psl;
2630	int i;
2631	int ret;
2632
2633	ret = 1;
2634	if (!ipv4_is_multicast(loc_addr))
2635		goto out;
2636
2637	rcu_read_lock();
2638	for_each_pmc_rcu(inet, pmc) {
2639		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2640		    (pmc->multi.imr_ifindex == dif ||
2641		     (sdif && pmc->multi.imr_ifindex == sdif)))
2642			break;
2643	}
2644	ret = inet->mc_all;
2645	if (!pmc)
2646		goto unlock;
2647	psl = rcu_dereference(pmc->sflist);
2648	ret = (pmc->sfmode == MCAST_EXCLUDE);
2649	if (!psl)
2650		goto unlock;
2651
2652	for (i = 0; i < psl->sl_count; i++) {
2653		if (psl->sl_addr[i] == rmt_addr)
2654			break;
2655	}
2656	ret = 0;
2657	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2658		goto unlock;
2659	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2660		goto unlock;
2661	ret = 1;
2662unlock:
2663	rcu_read_unlock();
2664out:
2665	return ret;
2666}
2667
2668/*
2669 *	A socket is closing.
2670 */
2671
2672void ip_mc_drop_socket(struct sock *sk)
2673{
2674	struct inet_sock *inet = inet_sk(sk);
2675	struct ip_mc_socklist *iml;
2676	struct net *net = sock_net(sk);
2677
2678	if (!inet->mc_list)
2679		return;
2680
2681	rtnl_lock();
2682	while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2683		struct in_device *in_dev;
2684
2685		inet->mc_list = iml->next_rcu;
2686		in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2687		(void) ip_mc_leave_src(sk, iml, in_dev);
2688		if (in_dev)
2689			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2690		/* decrease mem now to avoid the memleak warning */
2691		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2692		kfree_rcu(iml, rcu);
2693	}
2694	rtnl_unlock();
2695}
2696
2697/* called with rcu_read_lock() */
2698int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto)
2699{
2700	struct ip_mc_list *im;
2701	struct ip_mc_list __rcu **mc_hash;
2702	struct ip_sf_list *psf;
2703	int rv = 0;
2704
2705	mc_hash = rcu_dereference(in_dev->mc_hash);
2706	if (mc_hash) {
2707		u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
2708
2709		for (im = rcu_dereference(mc_hash[hash]);
2710		     im != NULL;
2711		     im = rcu_dereference(im->next_hash)) {
2712			if (im->multiaddr == mc_addr)
2713				break;
2714		}
2715	} else {
2716		for_each_pmc_rcu(in_dev, im) {
2717			if (im->multiaddr == mc_addr)
2718				break;
2719		}
2720	}
2721	if (im && proto == IPPROTO_IGMP) {
2722		rv = 1;
2723	} else if (im) {
2724		if (src_addr) {
 
2725			for (psf = im->sources; psf; psf = psf->sf_next) {
2726				if (psf->sf_inaddr == src_addr)
2727					break;
2728			}
2729			if (psf)
2730				rv = psf->sf_count[MCAST_INCLUDE] ||
2731					psf->sf_count[MCAST_EXCLUDE] !=
2732					im->sfcount[MCAST_EXCLUDE];
2733			else
2734				rv = im->sfcount[MCAST_EXCLUDE] != 0;
 
2735		} else
2736			rv = 1; /* unspecified source; tentatively allow */
2737	}
2738	return rv;
2739}
2740
2741#if defined(CONFIG_PROC_FS)
2742struct igmp_mc_iter_state {
2743	struct seq_net_private p;
2744	struct net_device *dev;
2745	struct in_device *in_dev;
2746};
2747
2748#define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)
2749
2750static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2751{
2752	struct net *net = seq_file_net(seq);
2753	struct ip_mc_list *im = NULL;
2754	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2755
2756	state->in_dev = NULL;
2757	for_each_netdev_rcu(net, state->dev) {
2758		struct in_device *in_dev;
2759
2760		in_dev = __in_dev_get_rcu(state->dev);
2761		if (!in_dev)
2762			continue;
2763		im = rcu_dereference(in_dev->mc_list);
2764		if (im) {
2765			state->in_dev = in_dev;
2766			break;
2767		}
2768	}
2769	return im;
2770}
2771
2772static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2773{
2774	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2775
2776	im = rcu_dereference(im->next_rcu);
2777	while (!im) {
2778		state->dev = next_net_device_rcu(state->dev);
2779		if (!state->dev) {
2780			state->in_dev = NULL;
2781			break;
2782		}
2783		state->in_dev = __in_dev_get_rcu(state->dev);
2784		if (!state->in_dev)
2785			continue;
2786		im = rcu_dereference(state->in_dev->mc_list);
2787	}
2788	return im;
2789}
2790
2791static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2792{
2793	struct ip_mc_list *im = igmp_mc_get_first(seq);
2794	if (im)
2795		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2796			--pos;
2797	return pos ? NULL : im;
2798}
2799
2800static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2801	__acquires(rcu)
2802{
2803	rcu_read_lock();
2804	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2805}
2806
2807static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2808{
2809	struct ip_mc_list *im;
2810	if (v == SEQ_START_TOKEN)
2811		im = igmp_mc_get_first(seq);
2812	else
2813		im = igmp_mc_get_next(seq, v);
2814	++*pos;
2815	return im;
2816}
2817
2818static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2819	__releases(rcu)
2820{
2821	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2822
2823	state->in_dev = NULL;
2824	state->dev = NULL;
2825	rcu_read_unlock();
2826}
2827
2828static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2829{
2830	if (v == SEQ_START_TOKEN)
2831		seq_puts(seq,
2832			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2833	else {
2834		struct ip_mc_list *im = (struct ip_mc_list *)v;
2835		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2836		char   *querier;
2837		long delta;
2838
2839#ifdef CONFIG_IP_MULTICAST
2840		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2841			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
2842			  "V3";
2843#else
2844		querier = "NONE";
2845#endif
2846
2847		if (rcu_access_pointer(state->in_dev->mc_list) == im) {
2848			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2849				   state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2850		}
2851
2852		delta = im->timer.expires - jiffies;
2853		seq_printf(seq,
2854			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2855			   im->multiaddr, im->users,
2856			   im->tm_running,
2857			   im->tm_running ? jiffies_delta_to_clock_t(delta) : 0,
2858			   im->reporter);
2859	}
2860	return 0;
2861}
2862
2863static const struct seq_operations igmp_mc_seq_ops = {
2864	.start	=	igmp_mc_seq_start,
2865	.next	=	igmp_mc_seq_next,
2866	.stop	=	igmp_mc_seq_stop,
2867	.show	=	igmp_mc_seq_show,
2868};
2869
2870struct igmp_mcf_iter_state {
2871	struct seq_net_private p;
2872	struct net_device *dev;
2873	struct in_device *idev;
2874	struct ip_mc_list *im;
2875};
2876
2877#define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)
2878
2879static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2880{
2881	struct net *net = seq_file_net(seq);
2882	struct ip_sf_list *psf = NULL;
2883	struct ip_mc_list *im = NULL;
2884	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2885
2886	state->idev = NULL;
2887	state->im = NULL;
2888	for_each_netdev_rcu(net, state->dev) {
2889		struct in_device *idev;
2890		idev = __in_dev_get_rcu(state->dev);
2891		if (unlikely(!idev))
2892			continue;
2893		im = rcu_dereference(idev->mc_list);
2894		if (likely(im)) {
2895			spin_lock_bh(&im->lock);
2896			psf = im->sources;
2897			if (likely(psf)) {
2898				state->im = im;
2899				state->idev = idev;
2900				break;
2901			}
2902			spin_unlock_bh(&im->lock);
2903		}
2904	}
2905	return psf;
2906}
2907
2908static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2909{
2910	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2911
2912	psf = psf->sf_next;
2913	while (!psf) {
2914		spin_unlock_bh(&state->im->lock);
2915		state->im = state->im->next;
2916		while (!state->im) {
2917			state->dev = next_net_device_rcu(state->dev);
2918			if (!state->dev) {
2919				state->idev = NULL;
2920				goto out;
2921			}
2922			state->idev = __in_dev_get_rcu(state->dev);
2923			if (!state->idev)
2924				continue;
2925			state->im = rcu_dereference(state->idev->mc_list);
2926		}
2927		if (!state->im)
2928			break;
2929		spin_lock_bh(&state->im->lock);
2930		psf = state->im->sources;
2931	}
2932out:
2933	return psf;
2934}
2935
2936static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2937{
2938	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2939	if (psf)
2940		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2941			--pos;
2942	return pos ? NULL : psf;
2943}
2944
2945static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2946	__acquires(rcu)
2947{
2948	rcu_read_lock();
2949	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2950}
2951
2952static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2953{
2954	struct ip_sf_list *psf;
2955	if (v == SEQ_START_TOKEN)
2956		psf = igmp_mcf_get_first(seq);
2957	else
2958		psf = igmp_mcf_get_next(seq, v);
2959	++*pos;
2960	return psf;
2961}
2962
2963static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2964	__releases(rcu)
2965{
2966	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2967	if (likely(state->im)) {
2968		spin_unlock_bh(&state->im->lock);
2969		state->im = NULL;
2970	}
2971	state->idev = NULL;
2972	state->dev = NULL;
2973	rcu_read_unlock();
2974}
2975
2976static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2977{
2978	struct ip_sf_list *psf = (struct ip_sf_list *)v;
2979	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2980
2981	if (v == SEQ_START_TOKEN) {
2982		seq_puts(seq, "Idx Device        MCA        SRC    INC    EXC\n");
2983	} else {
2984		seq_printf(seq,
2985			   "%3d %6.6s 0x%08x "
2986			   "0x%08x %6lu %6lu\n",
2987			   state->dev->ifindex, state->dev->name,
2988			   ntohl(state->im->multiaddr),
2989			   ntohl(psf->sf_inaddr),
2990			   psf->sf_count[MCAST_INCLUDE],
2991			   psf->sf_count[MCAST_EXCLUDE]);
2992	}
2993	return 0;
2994}
2995
2996static const struct seq_operations igmp_mcf_seq_ops = {
2997	.start	=	igmp_mcf_seq_start,
2998	.next	=	igmp_mcf_seq_next,
2999	.stop	=	igmp_mcf_seq_stop,
3000	.show	=	igmp_mcf_seq_show,
3001};
3002
3003static int __net_init igmp_net_init(struct net *net)
3004{
3005	struct proc_dir_entry *pde;
3006	int err;
3007
3008	pde = proc_create_net("igmp", 0444, net->proc_net, &igmp_mc_seq_ops,
3009			sizeof(struct igmp_mc_iter_state));
3010	if (!pde)
3011		goto out_igmp;
3012	pde = proc_create_net("mcfilter", 0444, net->proc_net,
3013			&igmp_mcf_seq_ops, sizeof(struct igmp_mcf_iter_state));
3014	if (!pde)
3015		goto out_mcfilter;
3016	err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET,
3017				   SOCK_DGRAM, 0, net);
3018	if (err < 0) {
3019		pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n",
3020		       err);
3021		goto out_sock;
3022	}
3023
3024	return 0;
3025
3026out_sock:
3027	remove_proc_entry("mcfilter", net->proc_net);
3028out_mcfilter:
3029	remove_proc_entry("igmp", net->proc_net);
3030out_igmp:
3031	return -ENOMEM;
3032}
3033
3034static void __net_exit igmp_net_exit(struct net *net)
3035{
3036	remove_proc_entry("mcfilter", net->proc_net);
3037	remove_proc_entry("igmp", net->proc_net);
3038	inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk);
3039}
3040
3041static struct pernet_operations igmp_net_ops = {
3042	.init = igmp_net_init,
3043	.exit = igmp_net_exit,
3044};
3045#endif
3046
3047static int igmp_netdev_event(struct notifier_block *this,
3048			     unsigned long event, void *ptr)
3049{
3050	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3051	struct in_device *in_dev;
3052
3053	switch (event) {
3054	case NETDEV_RESEND_IGMP:
3055		in_dev = __in_dev_get_rtnl(dev);
3056		if (in_dev)
3057			ip_mc_rejoin_groups(in_dev);
3058		break;
3059	default:
3060		break;
3061	}
3062	return NOTIFY_DONE;
3063}
3064
3065static struct notifier_block igmp_notifier = {
3066	.notifier_call = igmp_netdev_event,
3067};
3068
3069int __init igmp_mc_init(void)
3070{
3071#if defined(CONFIG_PROC_FS)
3072	int err;
3073
3074	err = register_pernet_subsys(&igmp_net_ops);
3075	if (err)
3076		return err;
3077	err = register_netdevice_notifier(&igmp_notifier);
3078	if (err)
3079		goto reg_notif_fail;
3080	return 0;
3081
3082reg_notif_fail:
3083	unregister_pernet_subsys(&igmp_net_ops);
3084	return err;
3085#else
3086	return register_netdevice_notifier(&igmp_notifier);
3087#endif
3088}
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}