net/ipv4/igmp.c

   1 /*
   2  *      Linux NET3:     Internet Group Management Protocol  [IGMP]
   3  *
   4  *      This code implements the IGMP protocol as defined in RFC1112. There has
   5  *      been a further revision of this protocol since which is now supported.
   6  *
   7  *      If you have trouble with this module be careful what gcc you have used,
   8  *      the older version didn't come out right using gcc 2.5.8, the newer one
   9  *      seems to fall out with gcc 2.6.2.
  10  *
  11  *      Version: $Id: igmp.c,v 1.47 2002/02/01 22:01:03 davem Exp $
  12  *
  13  *      Authors:
  14  *              Alan Cox <Alan.Cox@linux.org>
  15  *
  16  *      This program is free software; you can redistribute it and/or
  17  *      modify it under the terms of the GNU General Public License
  18  *      as published by the Free Software Foundation; either version
  19  *      2 of the License, or (at your option) any later version.
  20  *
  21  *      Fixes:
  22  *
  23  *              Alan Cox        :       Added lots of __inline__ to optimise
  24  *                                      the memory usage of all the tiny little
  25  *                                      functions.
  26  *              Alan Cox        :       Dumped the header building experiment.
  27  *              Alan Cox        :       Minor tweaks ready for multicast routing
  28  *                                      and extended IGMP protocol.
  29  *              Alan Cox        :       Removed a load of inline directives. Gcc 2.5.8
  30  *                                      writes utterly bogus code otherwise (sigh)
  31  *                                      fixed IGMP loopback to behave in the manner
  32  *                                      desired by mrouted, fixed the fact it has been
  33  *                                      broken since 1.3.6 and cleaned up a few minor
  34  *                                      points.
  35  *
  36  *              Chih-Jen Chang  :       Tried to revise IGMP to Version 2
  37  *              Tsu-Sheng Tsao          E-mail: chihjenc@scf.usc.edu and tsusheng@scf.usc.edu
  38  *                                      The enhancements are mainly based on Steve Deering's
  39  *                                      ipmulti-3.5 source code.
  40  *              Chih-Jen Chang  :       Added the igmp_get_mrouter_info and
  41  *              Tsu-Sheng Tsao          igmp_set_mrouter_info to keep track of
  42  *                                      the mrouted version on that device.
  43  *              Chih-Jen Chang  :       Added the max_resp_time parameter to
  44  *              Tsu-Sheng Tsao          igmp_heard_query(). Using this parameter
  45  *                                      to identify the multicast router version
  46  *                                      and do what the IGMP version 2 specified.
  47  *              Chih-Jen Chang  :       Added a timer to revert to IGMP V2 router
  48  *              Tsu-Sheng Tsao          if the specified time expired.
  49  *              Alan Cox        :       Stop IGMP from 0.0.0.0 being accepted.
  50  *              Alan Cox        :       Use GFP_ATOMIC in the right places.
  51  *              Christian Daudt :       igmp timer wasn't set for local group
  52  *                                      memberships but was being deleted,
  53  *                                      which caused a "del_timer() called
  54  *                                      from %p with timer not initialized\n"
  55  *                                      message (960131).
  56  *              Christian Daudt :       removed del_timer from
  57  *                                      igmp_timer_expire function (960205).
  58  *             Christian Daudt :       igmp_heard_report now only calls
  59  *                                     igmp_timer_expire if tm->running is
  60  *                                     true (960216).
  61  *              Malcolm Beattie :       ttl comparison wrong in igmp_rcv made
  62  *                                      igmp_heard_query never trigger. Expiry
  63  *                                      miscalculation fixed in igmp_heard_query
  64  *                                      and random() made to return unsigned to
  65  *                                      prevent negative expiry times.
  66  *              Alexey Kuznetsov:       Wrong group leaving behaviour, backport
  67  *                                      fix from pending 2.1.x patches.
  68  *              Alan Cox:               Forget to enable FDDI support earlier.
  69  *              Alexey Kuznetsov:       Fixed leaving groups on device down.
  70  *              Alexey Kuznetsov:       Accordance to igmp-v2-06 draft.
  71  *              David L Stevens:        IGMPv3 support, with help from
  72  *                                      Vinay Kulkarni
  73  */
  74
  75 #include <linux/config.h>
  76 #include <linux/module.h>
  77 #include <asm/uaccess.h>
  78 #include <asm/system.h>
  79 #include <linux/types.h>
  80 #include <linux/kernel.h>
  81 #include <linux/jiffies.h>
  82 #include <linux/string.h>
  83 #include <linux/socket.h>
  84 #include <linux/sockios.h>
  85 #include <linux/in.h>
  86 #include <linux/inet.h>
  87 #include <linux/netdevice.h>
  88 #include <linux/skbuff.h>
  89 #include <linux/inetdevice.h>
  90 #include <linux/igmp.h>
  91 #include <linux/if_arp.h>
  92 #include <linux/rtnetlink.h>
  93 #include <linux/times.h>
  94 #include <net/ip.h>
  95 #include <net/protocol.h>
  96 #include <net/route.h>
  97 #include <net/sock.h>
  98 #include <net/checksum.h>
  99 #include <linux/netfilter_ipv4.h>
 100 #ifdef CONFIG_IP_MROUTE
 101 #include <linux/mroute.h>
 102 #endif
 103 #ifdef CONFIG_PROC_FS
 104 #include <linux/proc_fs.h>
 105 #include <linux/seq_file.h>
 106 #endif
 107
 108 #define IP_MAX_MEMBERSHIPS      20
 109 #define IP_MAX_MSF              10
 110
 111 #ifdef CONFIG_IP_MULTICAST
 112 /* Parameter names and values are taken from igmp-v2-06 draft */
 113
 114 #define IGMP_V1_Router_Present_Timeout          (400*HZ)
 115 #define IGMP_V2_Router_Present_Timeout          (400*HZ)
 116 #define IGMP_Unsolicited_Report_Interval        (10*HZ)
 117 #define IGMP_Query_Response_Interval            (10*HZ)
 118 #define IGMP_Unsolicited_Report_Count           2
 119
 120
 121 #define IGMP_Initial_Report_Delay               (1)
 122
 123 /* IGMP_Initial_Report_Delay is not from IGMP specs!
 124  * IGMP specs require to report membership immediately after
 125  * joining a group, but we delay the first report by a
 126  * small interval. It seems more natural and still does not
 127  * contradict to specs provided this delay is small enough.
 128  */
 129
 130 #define IGMP_V1_SEEN(in_dev) (ipv4_devconf.force_igmp_version == 1 || \
 131                 (in_dev)->cnf.force_igmp_version == 1 || \
 132                 ((in_dev)->mr_v1_seen && \
 133                 time_before(jiffies, (in_dev)->mr_v1_seen)))
 134 #define IGMP_V2_SEEN(in_dev) (ipv4_devconf.force_igmp_version == 2 || \
 135                 (in_dev)->cnf.force_igmp_version == 2 || \
 136                 ((in_dev)->mr_v2_seen && \
 137                 time_before(jiffies, (in_dev)->mr_v2_seen)))
 138
 139 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im);
 140 static void igmpv3_del_delrec(struct in_device *in_dev, __u32 multiaddr);
 141 static void igmpv3_clear_delrec(struct in_device *in_dev);
 142 static int sf_setstate(struct ip_mc_list *pmc);
 143 static void sf_markstate(struct ip_mc_list *pmc);
 144 #endif
 145 static void ip_mc_clear_src(struct ip_mc_list *pmc);
 146 static int ip_mc_add_src(struct in_device *in_dev, __u32 *pmca, int sfmode,
 147                          int sfcount, __u32 *psfsrc, int delta);
 148
 149 static void ip_ma_put(struct ip_mc_list *im)
 150 {
 151         if (atomic_dec_and_test(&im->refcnt)) {
 152                 in_dev_put(im->interface);
 153                 kfree(im);
 154         }
 155 }
 156
 157 #ifdef CONFIG_IP_MULTICAST
 158
 159 /*
 160  *      Timer management
 161  */
 162
 163 static __inline__ void igmp_stop_timer(struct ip_mc_list *im)
 164 {
 165         spin_lock_bh(&im->lock);
 166         if (del_timer(&im->timer))
 167                 atomic_dec(&im->refcnt);
 168         im->tm_running=0;
 169         im->reporter = 0;
 170         im->unsolicit_count = 0;
 171         spin_unlock_bh(&im->lock);
 172 }
 173
 174 /* It must be called with locked im->lock */
 175 static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
 176 {
 177         int tv=net_random() % max_delay;
 178
 179         im->tm_running=1;
 180         if (!mod_timer(&im->timer, jiffies+tv+2))
 181                 atomic_inc(&im->refcnt);
 182 }
 183
 184 static void igmp_gq_start_timer(struct in_device *in_dev)
 185 {
 186         int tv = net_random() % in_dev->mr_maxdelay;
 187
 188         in_dev->mr_gq_running = 1;
 189         if (!mod_timer(&in_dev->mr_gq_timer, jiffies+tv+2))
 190                 in_dev_hold(in_dev);
 191 }
 192
 193 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
 194 {
 195         int tv = net_random() % delay;
 196
 197         if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
 198                 in_dev_hold(in_dev);
 199 }
 200
 201 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
 202 {
 203         spin_lock_bh(&im->lock);
 204         im->unsolicit_count = 0;
 205         if (del_timer(&im->timer)) {
 206                 if ((long)(im->timer.expires-jiffies) < max_delay) {
 207                         add_timer(&im->timer);
 208                         im->tm_running=1;
 209                         spin_unlock_bh(&im->lock);
 210                         return;
 211                 }
 212                 atomic_dec(&im->refcnt);
 213         }
 214         igmp_start_timer(im, max_delay);
 215         spin_unlock_bh(&im->lock);
 216 }
 217
 218
 219 /*
 220  *      Send an IGMP report.
 221  */
 222
 223 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
 224
 225
 226 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
 227         int gdeleted, int sdeleted)
 228 {
 229         switch (type) {
 230         case IGMPV3_MODE_IS_INCLUDE:
 231         case IGMPV3_MODE_IS_EXCLUDE:
 232                 if (gdeleted || sdeleted)
 233                         return 0;
 234                 return !(pmc->gsquery && !psf->sf_gsresp);
 235         case IGMPV3_CHANGE_TO_INCLUDE:
 236                 if (gdeleted || sdeleted)
 237                         return 0;
 238                 return psf->sf_count[MCAST_INCLUDE] != 0;
 239         case IGMPV3_CHANGE_TO_EXCLUDE:
 240                 if (gdeleted || sdeleted)
 241                         return 0;
 242                 if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
 243                     psf->sf_count[MCAST_INCLUDE])
 244                         return 0;
 245                 return pmc->sfcount[MCAST_EXCLUDE] ==
 246                         psf->sf_count[MCAST_EXCLUDE];
 247         case IGMPV3_ALLOW_NEW_SOURCES:
 248                 if (gdeleted || !psf->sf_crcount)
 249                         return 0;
 250                 return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
 251         case IGMPV3_BLOCK_OLD_SOURCES:
 252                 if (pmc->sfmode == MCAST_INCLUDE)
 253                         return gdeleted || (psf->sf_crcount && sdeleted);
 254                 return psf->sf_crcount && !gdeleted && !sdeleted;
 255         }
 256         return 0;
 257 }
 258
 259 static int
 260 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
 261 {
 262         struct ip_sf_list *psf;
 263         int scount = 0;
 264
 265         for (psf=pmc->sources; psf; psf=psf->sf_next) {
 266                 if (!is_in(pmc, psf, type, gdeleted, sdeleted))
 267                         continue;
 268                 scount++;
 269         }
 270         return scount;
 271 }
 272
 273 static struct sk_buff *igmpv3_newpack(struct net_device *dev, int size)
 274 {
 275         struct sk_buff *skb;
 276         struct rtable *rt;
 277         struct iphdr *pip;
 278         struct igmpv3_report *pig;
 279
 280         skb = alloc_skb(size + LL_RESERVED_SPACE(dev), GFP_ATOMIC);
 281         if (skb == NULL)
 282                 return NULL;
 283
 284         {
 285                 struct flowi fl = { .oif = dev->ifindex,
 286                                     .nl_u = { .ip4_u = {
 287                                     .daddr = IGMPV3_ALL_MCR } },
 288                                     .proto = IPPROTO_IGMP };
 289                 if (ip_route_output_key(&rt, &fl)) {
 290                         kfree_skb(skb);
 291                         return NULL;
 292                 }
 293         }
 294         if (rt->rt_src == 0) {
 295                 kfree_skb(skb);
 296                 ip_rt_put(rt);
 297                 return NULL;
 298         }
 299
 300         skb->dst = &rt->u.dst;
 301         skb->dev = dev;
 302
 303         skb_reserve(skb, LL_RESERVED_SPACE(dev));
 304
 305         skb->nh.iph = pip =(struct iphdr *)skb_put(skb, sizeof(struct iphdr)+4);
 306
 307         pip->version  = 4;
 308         pip->ihl      = (sizeof(struct iphdr)+4)>>2;
 309         pip->tos      = 0xc0;
 310         pip->frag_off = htons(IP_DF);
 311         pip->ttl      = 1;
 312         pip->daddr    = rt->rt_dst;
 313         pip->saddr    = rt->rt_src;
 314         pip->protocol = IPPROTO_IGMP;
 315         pip->tot_len  = 0;      /* filled in later */
 316         ip_select_ident(pip, &rt->u.dst, NULL);
 317         ((u8*)&pip[1])[0] = IPOPT_RA;
 318         ((u8*)&pip[1])[1] = 4;
 319         ((u8*)&pip[1])[2] = 0;
 320         ((u8*)&pip[1])[3] = 0;
 321
 322         pig =(struct igmpv3_report *)skb_put(skb, sizeof(*pig));
 323         skb->h.igmph = (struct igmphdr *)pig;
 324         pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
 325         pig->resv1 = 0;
 326         pig->csum = 0;
 327         pig->resv2 = 0;
 328         pig->ngrec = 0;
 329         return skb;
 330 }
 331
 332 static int igmpv3_sendpack(struct sk_buff *skb)
 333 {
 334         struct iphdr *pip = skb->nh.iph;
 335         struct igmphdr *pig = skb->h.igmph;
 336         int iplen, igmplen;
 337
 338         iplen = skb->tail - (unsigned char *)skb->nh.iph;
 339         pip->tot_len = htons(iplen);
 340         ip_send_check(pip);
 341
 342         igmplen = skb->tail - (unsigned char *)skb->h.igmph;
 343         pig->csum = ip_compute_csum((void *)skb->h.igmph, igmplen);
 344
 345         return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, skb->dev,
 346                        dst_output);
 347 }
 348
 349 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
 350 {
 351         return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc,type,gdel,sdel);
 352 }
 353
 354 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
 355         int type, struct igmpv3_grec **ppgr)
 356 {
 357         struct net_device *dev = pmc->interface->dev;
 358         struct igmpv3_report *pih;
 359         struct igmpv3_grec *pgr;
 360
 361         if (!skb)
 362                 skb = igmpv3_newpack(dev, dev->mtu);
 363         if (!skb)
 364                 return NULL;
 365         pgr = (struct igmpv3_grec *)skb_put(skb, sizeof(struct igmpv3_grec));
 366         pgr->grec_type = type;
 367         pgr->grec_auxwords = 0;
 368         pgr->grec_nsrcs = 0;
 369         pgr->grec_mca = pmc->multiaddr;
 370         pih = (struct igmpv3_report *)skb->h.igmph;
 371         pih->ngrec = htons(ntohs(pih->ngrec)+1);
 372         *ppgr = pgr;
 373         return skb;
 374 }
 375
 376 #define AVAILABLE(skb) ((skb) ? ((skb)->dev ? (skb)->dev->mtu - (skb)->len : \
 377         skb_tailroom(skb)) : 0)
 378
 379 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
 380         int type, int gdeleted, int sdeleted)
 381 {
 382         struct net_device *dev = pmc->interface->dev;
 383         struct igmpv3_report *pih;
 384         struct igmpv3_grec *pgr = NULL;
 385         struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
 386         int scount, first, isquery, truncate;
 387
 388         if (pmc->multiaddr == IGMP_ALL_HOSTS)
 389                 return skb;
 390
 391         isquery = type == IGMPV3_MODE_IS_INCLUDE ||
 392                   type == IGMPV3_MODE_IS_EXCLUDE;
 393         truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
 394                     type == IGMPV3_CHANGE_TO_EXCLUDE;
 395
 396         psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
 397
 398         if (!*psf_list) {
 399                 if (type == IGMPV3_ALLOW_NEW_SOURCES ||
 400                     type == IGMPV3_BLOCK_OLD_SOURCES)
 401                         return skb;
 402                 if (pmc->crcount || isquery) {
 403                         /* make sure we have room for group header and at
 404                          * least one source.
 405                          */
 406                         if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)+
 407                             sizeof(__u32)) {
 408                                 igmpv3_sendpack(skb);
 409                                 skb = NULL; /* add_grhead will get a new one */
 410                         }
 411                         skb = add_grhead(skb, pmc, type, &pgr);
 412                 }
 413                 return skb;
 414         }
 415         pih = skb ? (struct igmpv3_report *)skb->h.igmph : NULL;
 416
 417         /* EX and TO_EX get a fresh packet, if needed */
 418         if (truncate) {
 419                 if (pih && pih->ngrec &&
 420                     AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
 421                         if (skb)
 422                                 igmpv3_sendpack(skb);
 423                         skb = igmpv3_newpack(dev, dev->mtu);
 424                 }
 425         }
 426         first = 1;
 427         scount = 0;
 428         psf_prev = NULL;
 429         for (psf=*psf_list; psf; psf=psf_next) {
 430                 u32 *psrc;
 431
 432                 psf_next = psf->sf_next;
 433
 434                 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
 435                         psf_prev = psf;
 436                         continue;
 437                 }
 438
 439                 /* clear marks on query responses */
 440                 if (isquery)
 441                         psf->sf_gsresp = 0;
 442
 443                 if (AVAILABLE(skb) < sizeof(u32) +
 444                     first*sizeof(struct igmpv3_grec)) {
 445                         if (truncate && !first)
 446                                 break;   /* truncate these */
 447                         if (pgr)
 448                                 pgr->grec_nsrcs = htons(scount);
 449                         if (skb)
 450                                 igmpv3_sendpack(skb);
 451                         skb = igmpv3_newpack(dev, dev->mtu);
 452                         first = 1;
 453                         scount = 0;
 454                 }
 455                 if (first) {
 456                         skb = add_grhead(skb, pmc, type, &pgr);
 457                         first = 0;
 458                 }
 459                 psrc = (u32 *)skb_put(skb, sizeof(u32));
 460                 *psrc = psf->sf_inaddr;
 461                 scount++;
 462                 if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
 463                      type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
 464                         psf->sf_crcount--;
 465                         if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
 466                                 if (psf_prev)
 467                                         psf_prev->sf_next = psf->sf_next;
 468                                 else
 469                                         *psf_list = psf->sf_next;
 470                                 kfree(psf);
 471                                 continue;
 472                         }
 473                 }
 474                 psf_prev = psf;
 475         }
 476         if (pgr)
 477                 pgr->grec_nsrcs = htons(scount);
 478
 479         if (isquery)
 480                 pmc->gsquery = 0;       /* clear query state on report */
 481         return skb;
 482 }
 483
 484 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
 485 {
 486         struct sk_buff *skb = NULL;
 487         int type;
 488
 489         if (!pmc) {
 490                 read_lock(&in_dev->mc_list_lock);
 491                 for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
 492                         if (pmc->multiaddr == IGMP_ALL_HOSTS)
 493                                 continue;
 494                         spin_lock_bh(&pmc->lock);
 495                         if (pmc->sfcount[MCAST_EXCLUDE])
 496                                 type = IGMPV3_MODE_IS_EXCLUDE;
 497                         else
 498                                 type = IGMPV3_MODE_IS_INCLUDE;
 499                         skb = add_grec(skb, pmc, type, 0, 0);
 500                         spin_unlock_bh(&pmc->lock);
 501                 }
 502                 read_unlock(&in_dev->mc_list_lock);
 503         } else {
 504                 spin_lock_bh(&pmc->lock);
 505                 if (pmc->sfcount[MCAST_EXCLUDE])
 506                         type = IGMPV3_MODE_IS_EXCLUDE;
 507                 else
 508                         type = IGMPV3_MODE_IS_INCLUDE;
 509                 skb = add_grec(skb, pmc, type, 0, 0);
 510                 spin_unlock_bh(&pmc->lock);
 511         }
 512         if (!skb)
 513                 return 0;
 514         return igmpv3_sendpack(skb);
 515 }
 516
 517 /*
 518  * remove zero-count source records from a source filter list
 519  */
 520 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
 521 {
 522         struct ip_sf_list *psf_prev, *psf_next, *psf;
 523
 524         psf_prev = NULL;
 525         for (psf=*ppsf; psf; psf = psf_next) {
 526                 psf_next = psf->sf_next;
 527                 if (psf->sf_crcount == 0) {
 528                         if (psf_prev)
 529                                 psf_prev->sf_next = psf->sf_next;
 530                         else
 531                                 *ppsf = psf->sf_next;
 532                         kfree(psf);
 533                 } else
 534                         psf_prev = psf;
 535         }
 536 }
 537
 538 static void igmpv3_send_cr(struct in_device *in_dev)
 539 {
 540         struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
 541         struct sk_buff *skb = NULL;
 542         int type, dtype;
 543
 544         read_lock(&in_dev->mc_list_lock);
 545         spin_lock_bh(&in_dev->mc_tomb_lock);
 546
 547         /* deleted MCA's */
 548         pmc_prev = NULL;
 549         for (pmc=in_dev->mc_tomb; pmc; pmc=pmc_next) {
 550                 pmc_next = pmc->next;
 551                 if (pmc->sfmode == MCAST_INCLUDE) {
 552                         type = IGMPV3_BLOCK_OLD_SOURCES;
 553                         dtype = IGMPV3_BLOCK_OLD_SOURCES;
 554                         skb = add_grec(skb, pmc, type, 1, 0);
 555                         skb = add_grec(skb, pmc, dtype, 1, 1);
 556                 }
 557                 if (pmc->crcount) {
 558                         pmc->crcount--;
 559                         if (pmc->sfmode == MCAST_EXCLUDE) {
 560                                 type = IGMPV3_CHANGE_TO_INCLUDE;
 561                                 skb = add_grec(skb, pmc, type, 1, 0);
 562                         }
 563                         if (pmc->crcount == 0) {
 564                                 igmpv3_clear_zeros(&pmc->tomb);
 565                                 igmpv3_clear_zeros(&pmc->sources);
 566                         }
 567                 }
 568                 if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
 569                         if (pmc_prev)
 570                                 pmc_prev->next = pmc_next;
 571                         else
 572                                 in_dev->mc_tomb = pmc_next;
 573                         in_dev_put(pmc->interface);
 574                         kfree(pmc);
 575                 } else
 576                         pmc_prev = pmc;
 577         }
 578         spin_unlock_bh(&in_dev->mc_tomb_lock);
 579
 580         /* change recs */
 581         for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
 582                 spin_lock_bh(&pmc->lock);
 583                 if (pmc->sfcount[MCAST_EXCLUDE]) {
 584                         type = IGMPV3_BLOCK_OLD_SOURCES;
 585                         dtype = IGMPV3_ALLOW_NEW_SOURCES;
 586                 } else {
 587                         type = IGMPV3_ALLOW_NEW_SOURCES;
 588                         dtype = IGMPV3_BLOCK_OLD_SOURCES;
 589                 }
 590                 skb = add_grec(skb, pmc, type, 0, 0);
 591                 skb = add_grec(skb, pmc, dtype, 0, 1);  /* deleted sources */
 592
 593                 /* filter mode changes */
 594                 if (pmc->crcount) {
 595                         pmc->crcount--;
 596                         if (pmc->sfmode == MCAST_EXCLUDE)
 597                                 type = IGMPV3_CHANGE_TO_EXCLUDE;
 598                         else
 599                                 type = IGMPV3_CHANGE_TO_INCLUDE;
 600                         skb = add_grec(skb, pmc, type, 0, 0);
 601                 }
 602                 spin_unlock_bh(&pmc->lock);
 603         }
 604         read_unlock(&in_dev->mc_list_lock);
 605
 606         if (!skb)
 607                 return;
 608         (void) igmpv3_sendpack(skb);
 609 }
 610
 611 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
 612         int type)
 613 {
 614         struct sk_buff *skb;
 615         struct iphdr *iph;
 616         struct igmphdr *ih;
 617         struct rtable *rt;
 618         struct net_device *dev = in_dev->dev;
 619         u32     group = pmc ? pmc->multiaddr : 0;
 620         u32     dst;
 621
 622         if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
 623                 return igmpv3_send_report(in_dev, pmc);
 624         else if (type == IGMP_HOST_LEAVE_MESSAGE)
 625                 dst = IGMP_ALL_ROUTER;
 626         else
 627                 dst = group;
 628
 629         {
 630                 struct flowi fl = { .oif = dev->ifindex,
 631                                     .nl_u = { .ip4_u = { .daddr = dst } },
 632                                     .proto = IPPROTO_IGMP };
 633                 if (ip_route_output_key(&rt, &fl))
 634                         return -1;
 635         }
 636         if (rt->rt_src == 0) {
 637                 ip_rt_put(rt);
 638                 return -1;
 639         }
 640
 641         skb=alloc_skb(IGMP_SIZE+LL_RESERVED_SPACE(dev), GFP_ATOMIC);
 642         if (skb == NULL) {
 643                 ip_rt_put(rt);
 644                 return -1;
 645         }
 646
 647         skb->dst = &rt->u.dst;
 648
 649         skb_reserve(skb, LL_RESERVED_SPACE(dev));
 650
 651         skb->nh.iph = iph = (struct iphdr *)skb_put(skb, sizeof(struct iphdr)+4);
 652
 653         iph->version  = 4;
 654         iph->ihl      = (sizeof(struct iphdr)+4)>>2;
 655         iph->tos      = 0xc0;
 656         iph->frag_off = htons(IP_DF);
 657         iph->ttl      = 1;
 658         iph->daddr    = dst;
 659         iph->saddr    = rt->rt_src;
 660         iph->protocol = IPPROTO_IGMP;
 661         iph->tot_len  = htons(IGMP_SIZE);
 662         ip_select_ident(iph, &rt->u.dst, NULL);
 663         ((u8*)&iph[1])[0] = IPOPT_RA;
 664         ((u8*)&iph[1])[1] = 4;
 665         ((u8*)&iph[1])[2] = 0;
 666         ((u8*)&iph[1])[3] = 0;
 667         ip_send_check(iph);
 668
 669         ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
 670         ih->type=type;
 671         ih->code=0;
 672         ih->csum=0;
 673         ih->group=group;
 674         ih->csum=ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 675
 676         return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, rt->u.dst.dev,
 677                        dst_output);
 678 }
 679
 680 static void igmp_gq_timer_expire(unsigned long data)
 681 {
 682         struct in_device *in_dev = (struct in_device *)data;
 683
 684         in_dev->mr_gq_running = 0;
 685         igmpv3_send_report(in_dev, NULL);
 686         __in_dev_put(in_dev);
 687 }
 688
 689 static void igmp_ifc_timer_expire(unsigned long data)
 690 {
 691         struct in_device *in_dev = (struct in_device *)data;
 692
 693         igmpv3_send_cr(in_dev);
 694         if (in_dev->mr_ifc_count) {
 695                 in_dev->mr_ifc_count--;
 696                 igmp_ifc_start_timer(in_dev, IGMP_Unsolicited_Report_Interval);
 697         }
 698         __in_dev_put(in_dev);
 699 }
 700
 701 static void igmp_ifc_event(struct in_device *in_dev)
 702 {
 703         if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 704                 return;
 705         in_dev->mr_ifc_count = in_dev->mr_qrv ? in_dev->mr_qrv :
 706                 IGMP_Unsolicited_Report_Count;
 707         igmp_ifc_start_timer(in_dev, 1);
 708 }
 709
 710
 711 static void igmp_timer_expire(unsigned long data)
 712 {
 713         struct ip_mc_list *im=(struct ip_mc_list *)data;
 714         struct in_device *in_dev = im->interface;
 715
 716         spin_lock(&im->lock);
 717         im->tm_running=0;
 718
 719         if (im->unsolicit_count) {
 720                 im->unsolicit_count--;
 721                 igmp_start_timer(im, IGMP_Unsolicited_Report_Interval);
 722         }
 723         im->reporter = 1;
 724         spin_unlock(&im->lock);
 725
 726         if (IGMP_V1_SEEN(in_dev))
 727                 igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
 728         else if (IGMP_V2_SEEN(in_dev))
 729                 igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
 730         else
 731                 igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
 732
 733         ip_ma_put(im);
 734 }
 735
 736 static void igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __u32 *srcs)
 737 {
 738         struct ip_sf_list *psf;
 739         int i, scount;
 740
 741         scount = 0;
 742         for (psf=pmc->sources; psf; psf=psf->sf_next) {
 743                 if (scount == nsrcs)
 744                         break;
 745                 for (i=0; i<nsrcs; i++)
 746                         if (srcs[i] == psf->sf_inaddr) {
 747                                 psf->sf_gsresp = 1;
 748                                 scount++;
 749                                 break;
 750                         }
 751         }
 752 }
 753
 754 static void igmp_heard_report(struct in_device *in_dev, u32 group)
 755 {
 756         struct ip_mc_list *im;
 757
 758         /* Timers are only set for non-local groups */
 759
 760         if (group == IGMP_ALL_HOSTS)
 761                 return;
 762
 763         read_lock(&in_dev->mc_list_lock);
 764         for (im=in_dev->mc_list; im!=NULL; im=im->next) {
 765                 if (im->multiaddr == group) {
 766                         igmp_stop_timer(im);
 767                         break;
 768                 }
 769         }
 770         read_unlock(&in_dev->mc_list_lock);
 771 }
 772
 773 static void igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
 774         int len)
 775 {
 776         struct igmphdr          *ih = skb->h.igmph;
 777         struct igmpv3_query *ih3 = (struct igmpv3_query *)ih;
 778         struct ip_mc_list       *im;
 779         u32                     group = ih->group;
 780         int                     max_delay;
 781         int                     mark = 0;
 782
 783
 784         if (len == 8) {
 785                 if (ih->code == 0) {
 786                         /* Alas, old v1 router presents here. */
 787
 788                         max_delay = IGMP_Query_Response_Interval;
 789                         in_dev->mr_v1_seen = jiffies +
 790                                 IGMP_V1_Router_Present_Timeout;
 791                         group = 0;
 792                 } else {
 793                         /* v2 router present */
 794                         max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
 795                         in_dev->mr_v2_seen = jiffies +
 796                                 IGMP_V2_Router_Present_Timeout;
 797                 }
 798                 /* cancel the interface change timer */
 799                 in_dev->mr_ifc_count = 0;
 800                 if (del_timer(&in_dev->mr_ifc_timer))
 801                         __in_dev_put(in_dev);
 802                 /* clear deleted report items */
 803                 igmpv3_clear_delrec(in_dev);
 804         } else if (len < 12) {
 805                 return; /* ignore bogus packet; freed by caller */
 806         } else { /* v3 */
 807                 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
 808                         return;
 809
 810                 ih3 = (struct igmpv3_query *) skb->h.raw;
 811                 if (ih3->nsrcs) {
 812                         if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
 813                                            + ntohs(ih3->nsrcs)*sizeof(__u32)))
 814                                 return;
 815                         ih3 = (struct igmpv3_query *) skb->h.raw;
 816                 }
 817
 818                 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 819                 if (!max_delay)
 820                         max_delay = 1;  /* can't mod w/ 0 */
 821                 in_dev->mr_maxdelay = max_delay;
 822                 if (ih3->qrv)
 823                         in_dev->mr_qrv = ih3->qrv;
 824                 if (!group) { /* general query */
 825                         if (ih3->nsrcs)
 826                                 return; /* no sources allowed */
 827                         igmp_gq_start_timer(in_dev);
 828                         return;
 829                 }
 830                 /* mark sources to include, if group & source-specific */
 831                 mark = ih3->nsrcs != 0;
 832         }
 833
 834         /*
 835          * - Start the timers in all of our membership records
 836          *   that the query applies to for the interface on
 837          *   which the query arrived excl. those that belong
 838          *   to a "local" group (224.0.0.X)
 839          * - For timers already running check if they need to
 840          *   be reset.
 841          * - Use the igmp->igmp_code field as the maximum
 842          *   delay possible
 843          */
 844         read_lock(&in_dev->mc_list_lock);
 845         for (im=in_dev->mc_list; im!=NULL; im=im->next) {
 846                 if (group && group != im->multiaddr)
 847                         continue;
 848                 if (im->multiaddr == IGMP_ALL_HOSTS)
 849                         continue;
 850                 spin_lock_bh(&im->lock);
 851                 if (im->tm_running)
 852                         im->gsquery = im->gsquery && mark;
 853                 else
 854                         im->gsquery = mark;
 855                 if (im->gsquery)
 856                         igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
 857                 spin_unlock_bh(&im->lock);
 858                 igmp_mod_timer(im, max_delay);
 859         }
 860         read_unlock(&in_dev->mc_list_lock);
 861 }
 862
 863 int igmp_rcv(struct sk_buff *skb)
 864 {
 865         /* This basically follows the spec line by line -- see RFC1112 */
 866         struct igmphdr *ih;
 867         struct in_device *in_dev = in_dev_get(skb->dev);
 868         int len = skb->len;
 869
 870         if (in_dev==NULL) {
 871                 kfree_skb(skb);
 872                 return 0;
 873         }
 874
 875         if (!pskb_may_pull(skb, sizeof(struct igmphdr)) ||
 876             (u16)csum_fold(skb_checksum(skb, 0, len, 0))) {
 877                 in_dev_put(in_dev);
 878                 kfree_skb(skb);
 879                 return 0;
 880         }
 881
 882         ih = skb->h.igmph;
 883         switch (ih->type) {
 884         case IGMP_HOST_MEMBERSHIP_QUERY:
 885                 igmp_heard_query(in_dev, skb, len);
 886                 break;
 887         case IGMP_HOST_MEMBERSHIP_REPORT:
 888         case IGMPV2_HOST_MEMBERSHIP_REPORT:
 889         case IGMPV3_HOST_MEMBERSHIP_REPORT:
 890                 /* Is it our report looped back? */
 891                 if (((struct rtable*)skb->dst)->fl.iif == 0)
 892                         break;
 893                 igmp_heard_report(in_dev, ih->group);
 894                 break;
 895         case IGMP_PIM:
 896 #ifdef CONFIG_IP_PIMSM_V1
 897                 in_dev_put(in_dev);
 898                 return pim_rcv_v1(skb);
 899 #endif
 900         case IGMP_DVMRP:
 901         case IGMP_TRACE:
 902         case IGMP_HOST_LEAVE_MESSAGE:
 903         case IGMP_MTRACE:
 904         case IGMP_MTRACE_RESP:
 905                 break;
 906         default:
 907                 NETDEBUG(printk(KERN_DEBUG "New IGMP type=%d, why we do not know about it?\n", ih->type));
 908         }
 909         in_dev_put(in_dev);
 910         kfree_skb(skb);
 911         return 0;
 912 }
 913
 914 #endif
 915
 916
 917 /*
 918  *      Add a filter to a device
 919  */
 920
 921 static void ip_mc_filter_add(struct in_device *in_dev, u32 addr)
 922 {
 923         char buf[MAX_ADDR_LEN];
 924         struct net_device *dev = in_dev->dev;
 925
 926         /* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
 927            We will get multicast token leakage, when IFF_MULTICAST
 928            is changed. This check should be done in dev->set_multicast_list
 929            routine. Something sort of:
 930            if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
 931            --ANK
 932            */
 933         if (arp_mc_map(addr, buf, dev, 0) == 0)
 934                 dev_mc_add(dev,buf,dev->addr_len,0);
 935 }
 936
 937 /*
 938  *      Remove a filter from a device
 939  */
 940
 941 static void ip_mc_filter_del(struct in_device *in_dev, u32 addr)
 942 {
 943         char buf[MAX_ADDR_LEN];
 944         struct net_device *dev = in_dev->dev;
 945
 946         if (arp_mc_map(addr, buf, dev, 0) == 0)
 947                 dev_mc_delete(dev,buf,dev->addr_len,0);
 948 }
 949
 950 #ifdef CONFIG_IP_MULTICAST
 951 /*
 952  * deleted ip_mc_list manipulation
 953  */
 954 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
 955 {
 956         struct ip_mc_list *pmc;
 957
 958         /* this is an "ip_mc_list" for convenience; only the fields below
 959          * are actually used. In particular, the refcnt and users are not
 960          * used for management of the delete list. Using the same structure
 961          * for deleted items allows change reports to use common code with
 962          * non-deleted or query-response MCA's.
 963          */
 964         pmc = (struct ip_mc_list *)kmalloc(sizeof(*pmc), GFP_KERNEL);
 965         if (!pmc)
 966                 return;
 967         memset(pmc, 0, sizeof(*pmc));
 968         spin_lock_bh(&im->lock);
 969         pmc->interface = im->interface;
 970         in_dev_hold(in_dev);
 971         pmc->multiaddr = im->multiaddr;
 972         pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
 973                 IGMP_Unsolicited_Report_Count;
 974         pmc->sfmode = im->sfmode;
 975         if (pmc->sfmode == MCAST_INCLUDE) {
 976                 struct ip_sf_list *psf;
 977
 978                 pmc->tomb = im->tomb;
 979                 pmc->sources = im->sources;
 980                 im->tomb = im->sources = NULL;
 981                 for (psf=pmc->sources; psf; psf=psf->sf_next)
 982                         psf->sf_crcount = pmc->crcount;
 983         }
 984         spin_unlock_bh(&im->lock);
 985
 986         spin_lock_bh(&in_dev->mc_tomb_lock);
 987         pmc->next = in_dev->mc_tomb;
 988         in_dev->mc_tomb = pmc;
 989         spin_unlock_bh(&in_dev->mc_tomb_lock);
 990 }
 991
 992 static void igmpv3_del_delrec(struct in_device *in_dev, __u32 multiaddr)
 993 {
 994         struct ip_mc_list *pmc, *pmc_prev;
 995         struct ip_sf_list *psf, *psf_next;
 996
 997         spin_lock_bh(&in_dev->mc_tomb_lock);
 998         pmc_prev = NULL;
 999         for (pmc=in_dev->mc_tomb; pmc; pmc=pmc->next) {
1000                 if (pmc->multiaddr == multiaddr)
1001                         break;
1002                 pmc_prev = pmc;
1003         }
1004         if (pmc) {
1005                 if (pmc_prev)
1006                         pmc_prev->next = pmc->next;
1007                 else
1008                         in_dev->mc_tomb = pmc->next;
1009         }
1010         spin_unlock_bh(&in_dev->mc_tomb_lock);
1011         if (pmc) {
1012                 for (psf=pmc->tomb; psf; psf=psf_next) {
1013                         psf_next = psf->sf_next;
1014                         kfree(psf);
1015                 }
1016                 in_dev_put(pmc->interface);
1017                 kfree(pmc);
1018         }
1019 }
1020
1021 static void igmpv3_clear_delrec(struct in_device *in_dev)
1022 {
1023         struct ip_mc_list *pmc, *nextpmc;
1024
1025         spin_lock_bh(&in_dev->mc_tomb_lock);
1026         pmc = in_dev->mc_tomb;
1027         in_dev->mc_tomb = NULL;
1028         spin_unlock_bh(&in_dev->mc_tomb_lock);
1029
1030         for (; pmc; pmc = nextpmc) {
1031                 nextpmc = pmc->next;
1032                 ip_mc_clear_src(pmc);
1033                 in_dev_put(pmc->interface);
1034                 kfree(pmc);
1035         }
1036         /* clear dead sources, too */
1037         read_lock(&in_dev->mc_list_lock);
1038         for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1039                 struct ip_sf_list *psf, *psf_next;
1040
1041                 spin_lock_bh(&pmc->lock);
1042                 psf = pmc->tomb;
1043                 pmc->tomb = NULL;
1044                 spin_unlock_bh(&pmc->lock);
1045                 for (; psf; psf=psf_next) {
1046                         psf_next = psf->sf_next;
1047                         kfree(psf);
1048                 }
1049         }
1050         read_unlock(&in_dev->mc_list_lock);
1051 }
1052 #endif
1053
1054 static void igmp_group_dropped(struct ip_mc_list *im)
1055 {
1056         struct in_device *in_dev = im->interface;
1057 #ifdef CONFIG_IP_MULTICAST
1058         int reporter;
1059 #endif
1060
1061         if (im->loaded) {
1062                 im->loaded = 0;
1063                 ip_mc_filter_del(in_dev, im->multiaddr);
1064         }
1065
1066 #ifdef CONFIG_IP_MULTICAST
1067         if (im->multiaddr == IGMP_ALL_HOSTS)
1068                 return;
1069
1070         reporter = im->reporter;
1071         igmp_stop_timer(im);
1072
1073         if (!in_dev->dead) {
1074                 if (IGMP_V1_SEEN(in_dev))
1075                         goto done;
1076                 if (IGMP_V2_SEEN(in_dev)) {
1077                         if (reporter)
1078                                 igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1079                         goto done;
1080                 }
1081                 /* IGMPv3 */
1082                 igmpv3_add_delrec(in_dev, im);
1083
1084                 igmp_ifc_event(in_dev);
1085         }
1086 done:
1087 #endif
1088         ip_mc_clear_src(im);
1089 }
1090
1091 static void igmp_group_added(struct ip_mc_list *im)
1092 {
1093         struct in_device *in_dev = im->interface;
1094
1095         if (im->loaded == 0) {
1096                 im->loaded = 1;
1097                 ip_mc_filter_add(in_dev, im->multiaddr);
1098         }
1099
1100 #ifdef CONFIG_IP_MULTICAST
1101         if (im->multiaddr == IGMP_ALL_HOSTS)
1102                 return;
1103
1104         if (in_dev->dead)
1105                 return;
1106         if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1107                 spin_lock_bh(&im->lock);
1108                 igmp_start_timer(im, IGMP_Initial_Report_Delay);
1109                 spin_unlock_bh(&im->lock);
1110                 return;
1111         }
1112         /* else, v3 */
1113
1114         im->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1115                 IGMP_Unsolicited_Report_Count;
1116         igmp_ifc_event(in_dev);
1117 #endif
1118 }
1119
1120
1121 /*
1122  *      Multicast list managers
1123  */
1124
1125
1126 /*
1127  *      A socket has joined a multicast group on device dev.
1128  */
1129
1130 void ip_mc_inc_group(struct in_device *in_dev, u32 addr)
1131 {
1132         struct ip_mc_list *im;
1133
1134         ASSERT_RTNL();
1135
1136         for (im=in_dev->mc_list; im; im=im->next) {
1137                 if (im->multiaddr == addr) {
1138                         im->users++;
1139                         ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1140                         goto out;
1141                 }
1142         }
1143
1144         im = (struct ip_mc_list *)kmalloc(sizeof(*im), GFP_KERNEL);
1145         if (!im)
1146                 goto out;
1147
1148         im->users=1;
1149         im->interface=in_dev;
1150         in_dev_hold(in_dev);
1151         im->multiaddr=addr;
1152         /* initial mode is (EX, empty) */
1153         im->sfmode = MCAST_EXCLUDE;
1154         im->sfcount[MCAST_INCLUDE] = 0;
1155         im->sfcount[MCAST_EXCLUDE] = 1;
1156         im->sources = NULL;
1157         im->tomb = NULL;
1158         im->crcount = 0;
1159         atomic_set(&im->refcnt, 1);
1160         spin_lock_init(&im->lock);
1161 #ifdef CONFIG_IP_MULTICAST
1162         im->tm_running=0;
1163         init_timer(&im->timer);
1164         im->timer.data=(unsigned long)im;
1165         im->timer.function=&igmp_timer_expire;
1166         im->unsolicit_count = IGMP_Unsolicited_Report_Count;
1167         im->reporter = 0;
1168         im->gsquery = 0;
1169 #endif
1170         im->loaded = 0;
1171         write_lock_bh(&in_dev->mc_list_lock);
1172         im->next=in_dev->mc_list;
1173         in_dev->mc_list=im;
1174         write_unlock_bh(&in_dev->mc_list_lock);
1175 #ifdef CONFIG_IP_MULTICAST
1176         igmpv3_del_delrec(in_dev, im->multiaddr);
1177 #endif
1178         igmp_group_added(im);
1179         if (!in_dev->dead)
1180                 ip_rt_multicast_event(in_dev);
1181 out:
1182         return;
1183 }
1184
1185 /*
1186  *      A socket has left a multicast group on device dev
1187  */
1188
1189 void ip_mc_dec_group(struct in_device *in_dev, u32 addr)
1190 {
1191         struct ip_mc_list *i, **ip;
1192
1193         ASSERT_RTNL();
1194
1195         for (ip=&in_dev->mc_list; (i=*ip)!=NULL; ip=&i->next) {
1196                 if (i->multiaddr==addr) {
1197                         if (--i->users == 0) {
1198                                 write_lock_bh(&in_dev->mc_list_lock);
1199                                 *ip = i->next;
1200                                 write_unlock_bh(&in_dev->mc_list_lock);
1201                                 igmp_group_dropped(i);
1202
1203                                 if (!in_dev->dead)
1204                                         ip_rt_multicast_event(in_dev);
1205
1206                                 ip_ma_put(i);
1207                                 return;
1208                         }
1209                         break;
1210                 }
1211         }
1212 }
1213
1214 /* Device going down */
1215
1216 void ip_mc_down(struct in_device *in_dev)
1217 {
1218         struct ip_mc_list *i;
1219
1220         ASSERT_RTNL();
1221
1222         for (i=in_dev->mc_list; i; i=i->next)
1223                 igmp_group_dropped(i);
1224
1225 #ifdef CONFIG_IP_MULTICAST
1226         in_dev->mr_ifc_count = 0;
1227         if (del_timer(&in_dev->mr_ifc_timer))
1228                 __in_dev_put(in_dev);
1229         in_dev->mr_gq_running = 0;
1230         if (del_timer(&in_dev->mr_gq_timer))
1231                 __in_dev_put(in_dev);
1232         igmpv3_clear_delrec(in_dev);
1233 #endif
1234
1235         ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1236 }
1237
1238 void ip_mc_init_dev(struct in_device *in_dev)
1239 {
1240         ASSERT_RTNL();
1241
1242         in_dev->mc_tomb = NULL;
1243 #ifdef CONFIG_IP_MULTICAST
1244         in_dev->mr_gq_running = 0;
1245         init_timer(&in_dev->mr_gq_timer);
1246         in_dev->mr_gq_timer.data=(unsigned long) in_dev;
1247         in_dev->mr_gq_timer.function=&igmp_gq_timer_expire;
1248         in_dev->mr_ifc_count = 0;
1249         init_timer(&in_dev->mr_ifc_timer);
1250         in_dev->mr_ifc_timer.data=(unsigned long) in_dev;
1251         in_dev->mr_ifc_timer.function=&igmp_ifc_timer_expire;
1252         in_dev->mr_qrv = IGMP_Unsolicited_Report_Count;
1253 #endif
1254
1255         rwlock_init(&in_dev->mc_list_lock);
1256         spin_lock_init(&in_dev->mc_tomb_lock);
1257 }
1258
1259 /* Device going up */
1260
1261 void ip_mc_up(struct in_device *in_dev)
1262 {
1263         struct ip_mc_list *i;
1264
1265         ASSERT_RTNL();
1266
1267         ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1268
1269         for (i=in_dev->mc_list; i; i=i->next)
1270                 igmp_group_added(i);
1271 }
1272
1273 /*
1274  *      Device is about to be destroyed: clean up.
1275  */
1276
1277 void ip_mc_destroy_dev(struct in_device *in_dev)
1278 {
1279         struct ip_mc_list *i;
1280
1281         ASSERT_RTNL();
1282
1283         /* Deactivate timers */
1284         ip_mc_down(in_dev);
1285
1286         write_lock_bh(&in_dev->mc_list_lock);
1287         while ((i = in_dev->mc_list) != NULL) {
1288                 in_dev->mc_list = i->next;
1289                 write_unlock_bh(&in_dev->mc_list_lock);
1290
1291                 igmp_group_dropped(i);
1292                 ip_ma_put(i);
1293
1294                 write_lock_bh(&in_dev->mc_list_lock);
1295         }
1296         write_unlock_bh(&in_dev->mc_list_lock);
1297 }
1298
1299 static struct in_device * ip_mc_find_dev(struct ip_mreqn *imr)
1300 {
1301         struct flowi fl = { .nl_u = { .ip4_u =
1302                                       { .daddr = imr->imr_multiaddr.s_addr } } };
1303         struct rtable *rt;
1304         struct net_device *dev = NULL;
1305         struct in_device *idev = NULL;
1306
1307         if (imr->imr_ifindex) {
1308                 idev = inetdev_by_index(imr->imr_ifindex);
1309                 if (idev)
1310                         __in_dev_put(idev);
1311                 return idev;
1312         }
1313         if (imr->imr_address.s_addr) {
1314                 dev = ip_dev_find(imr->imr_address.s_addr);
1315                 if (!dev)
1316                         return NULL;
1317                 __dev_put(dev);
1318         }
1319
1320         if (!dev && !ip_route_output_key(&rt, &fl)) {
1321                 dev = rt->u.dst.dev;
1322                 ip_rt_put(rt);
1323         }
1324         if (dev) {
1325                 imr->imr_ifindex = dev->ifindex;
1326                 idev = __in_dev_get(dev);
1327         }
1328         return idev;
1329 }
1330
1331 /*
1332  *      Join a socket to a group
1333  */
1334 int sysctl_igmp_max_memberships = IP_MAX_MEMBERSHIPS;
1335 int sysctl_igmp_max_msf = IP_MAX_MSF;
1336
1337
1338 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1339         __u32 *psfsrc)
1340 {
1341         struct ip_sf_list *psf, *psf_prev;
1342         int rv = 0;
1343
1344         psf_prev = NULL;
1345         for (psf=pmc->sources; psf; psf=psf->sf_next) {
1346                 if (psf->sf_inaddr == *psfsrc)
1347                         break;
1348                 psf_prev = psf;
1349         }
1350         if (!psf || psf->sf_count[sfmode] == 0) {
1351                 /* source filter not found, or count wrong =>  bug */
1352                 return -ESRCH;
1353         }
1354         psf->sf_count[sfmode]--;
1355         if (psf->sf_count[sfmode] == 0) {
1356                 ip_rt_multicast_event(pmc->interface);
1357         }
1358         if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1359 #ifdef CONFIG_IP_MULTICAST
1360                 struct in_device *in_dev = pmc->interface;
1361 #endif
1362
1363                 /* no more filters for this source */
1364                 if (psf_prev)
1365                         psf_prev->sf_next = psf->sf_next;
1366                 else
1367                         pmc->sources = psf->sf_next;
1368 #ifdef CONFIG_IP_MULTICAST
1369                 if (psf->sf_oldin &&
1370                     !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1371                         psf->sf_crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1372                                 IGMP_Unsolicited_Report_Count;
1373                         psf->sf_next = pmc->tomb;
1374                         pmc->tomb = psf;
1375                         rv = 1;
1376                 } else
1377 #endif
1378                         kfree(psf);
1379         }
1380         return rv;
1381 }
1382
1383 #ifndef CONFIG_IP_MULTICAST
1384 #define igmp_ifc_event(x)       do { } while (0)
1385 #endif
1386
1387 static int ip_mc_del_src(struct in_device *in_dev, __u32 *pmca, int sfmode,
1388                          int sfcount, __u32 *psfsrc, int delta)
1389 {
1390         struct ip_mc_list *pmc;
1391         int     changerec = 0;
1392         int     i, err;
1393
1394         if (!in_dev)
1395                 return -ENODEV;
1396         read_lock(&in_dev->mc_list_lock);
1397         for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1398                 if (*pmca == pmc->multiaddr)
1399                         break;
1400         }
1401         if (!pmc) {
1402                 /* MCA not found?? bug */
1403                 read_unlock(&in_dev->mc_list_lock);
1404                 return -ESRCH;
1405         }
1406         spin_lock_bh(&pmc->lock);
1407         read_unlock(&in_dev->mc_list_lock);
1408 #ifdef CONFIG_IP_MULTICAST
1409         sf_markstate(pmc);
1410 #endif
1411         if (!delta) {
1412                 err = -EINVAL;
1413                 if (!pmc->sfcount[sfmode])
1414                         goto out_unlock;
1415                 pmc->sfcount[sfmode]--;
1416         }
1417         err = 0;
1418         for (i=0; i<sfcount; i++) {
1419                 int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1420
1421                 changerec |= rv > 0;
1422                 if (!err && rv < 0)
1423                         err = rv;
1424         }
1425         if (pmc->sfmode == MCAST_EXCLUDE &&
1426             pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1427             pmc->sfcount[MCAST_INCLUDE]) {
1428 #ifdef CONFIG_IP_MULTICAST
1429                 struct ip_sf_list *psf;
1430 #endif
1431
1432                 /* filter mode change */
1433                 pmc->sfmode = MCAST_INCLUDE;
1434 #ifdef CONFIG_IP_MULTICAST
1435                 pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1436                         IGMP_Unsolicited_Report_Count;
1437                 in_dev->mr_ifc_count = pmc->crcount;
1438                 for (psf=pmc->sources; psf; psf = psf->sf_next)
1439                         psf->sf_crcount = 0;
1440                 igmp_ifc_event(pmc->interface);
1441         } else if (sf_setstate(pmc) || changerec) {
1442                 igmp_ifc_event(pmc->interface);
1443 #endif
1444         }
1445 out_unlock:
1446         spin_unlock_bh(&pmc->lock);
1447         return err;
1448 }
1449
1450 /*
1451  * Add multicast single-source filter to the interface list
1452  */
1453 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1454         __u32 *psfsrc, int delta)
1455 {
1456         struct ip_sf_list *psf, *psf_prev;
1457
1458         psf_prev = NULL;
1459         for (psf=pmc->sources; psf; psf=psf->sf_next) {
1460                 if (psf->sf_inaddr == *psfsrc)
1461                         break;
1462                 psf_prev = psf;
1463         }
1464         if (!psf) {
1465                 psf = (struct ip_sf_list *)kmalloc(sizeof(*psf), GFP_ATOMIC);
1466                 if (!psf)
1467                         return -ENOBUFS;
1468                 memset(psf, 0, sizeof(*psf));
1469                 psf->sf_inaddr = *psfsrc;
1470                 if (psf_prev) {
1471                         psf_prev->sf_next = psf;
1472                 } else
1473                         pmc->sources = psf;
1474         }
1475         psf->sf_count[sfmode]++;
1476         if (psf->sf_count[sfmode] == 1) {
1477                 ip_rt_multicast_event(pmc->interface);
1478         }
1479         return 0;
1480 }
1481
1482 #ifdef CONFIG_IP_MULTICAST
1483 static void sf_markstate(struct ip_mc_list *pmc)
1484 {
1485         struct ip_sf_list *psf;
1486         int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1487
1488         for (psf=pmc->sources; psf; psf=psf->sf_next)
1489                 if (pmc->sfcount[MCAST_EXCLUDE]) {
1490                         psf->sf_oldin = mca_xcount ==
1491                                 psf->sf_count[MCAST_EXCLUDE] &&
1492                                 !psf->sf_count[MCAST_INCLUDE];
1493                 } else
1494                         psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1495 }
1496
1497 static int sf_setstate(struct ip_mc_list *pmc)
1498 {
1499         struct ip_sf_list *psf;
1500         int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1501         int qrv = pmc->interface->mr_qrv;
1502         int new_in, rv;
1503
1504         rv = 0;
1505         for (psf=pmc->sources; psf; psf=psf->sf_next) {
1506                 if (pmc->sfcount[MCAST_EXCLUDE]) {
1507                         new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1508                                 !psf->sf_count[MCAST_INCLUDE];
1509                 } else
1510                         new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1511                 if (new_in != psf->sf_oldin) {
1512                         psf->sf_crcount = qrv;
1513                         rv++;
1514                 }
1515         }
1516         return rv;
1517 }
1518 #endif
1519
1520 /*
1521  * Add multicast source filter list to the interface list
1522  */
1523 static int ip_mc_add_src(struct in_device *in_dev, __u32 *pmca, int sfmode,
1524                          int sfcount, __u32 *psfsrc, int delta)
1525 {
1526         struct ip_mc_list *pmc;
1527         int     isexclude;
1528         int     i, err;
1529
1530         if (!in_dev)
1531                 return -ENODEV;
1532         read_lock(&in_dev->mc_list_lock);
1533         for (pmc=in_dev->mc_list; pmc; pmc=pmc->next) {
1534                 if (*pmca == pmc->multiaddr)
1535                         break;
1536         }
1537         if (!pmc) {
1538                 /* MCA not found?? bug */
1539                 read_unlock(&in_dev->mc_list_lock);
1540                 return -ESRCH;
1541         }
1542         spin_lock_bh(&pmc->lock);
1543         read_unlock(&in_dev->mc_list_lock);
1544
1545 #ifdef CONFIG_IP_MULTICAST
1546         sf_markstate(pmc);
1547 #endif
1548         isexclude = pmc->sfmode == MCAST_EXCLUDE;
1549         if (!delta)
1550                 pmc->sfcount[sfmode]++;
1551         err = 0;
1552         for (i=0; i<sfcount; i++) {
1553                 err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i], delta);
1554                 if (err)
1555                         break;
1556         }
1557         if (err) {
1558                 int j;
1559
1560                 pmc->sfcount[sfmode]--;
1561                 for (j=0; j<i; j++)
1562                         (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1563         } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
1564 #ifdef CONFIG_IP_MULTICAST
1565                 struct in_device *in_dev = pmc->interface;
1566                 struct ip_sf_list *psf;
1567 #endif
1568
1569                 /* filter mode change */
1570                 if (pmc->sfcount[MCAST_EXCLUDE])
1571                         pmc->sfmode = MCAST_EXCLUDE;
1572                 else if (pmc->sfcount[MCAST_INCLUDE])
1573                         pmc->sfmode = MCAST_INCLUDE;
1574 #ifdef CONFIG_IP_MULTICAST
1575                 /* else no filters; keep old mode for reports */
1576
1577                 pmc->crcount = in_dev->mr_qrv ? in_dev->mr_qrv :
1578                         IGMP_Unsolicited_Report_Count;
1579                 in_dev->mr_ifc_count = pmc->crcount;
1580                 for (psf=pmc->sources; psf; psf = psf->sf_next)
1581                         psf->sf_crcount = 0;
1582                 igmp_ifc_event(in_dev);
1583         } else if (sf_setstate(pmc)) {
1584                 igmp_ifc_event(in_dev);
1585 #endif
1586         }
1587         spin_unlock_bh(&pmc->lock);
1588         return err;
1589 }
1590
1591 static void ip_mc_clear_src(struct ip_mc_list *pmc)
1592 {
1593         struct ip_sf_list *psf, *nextpsf;
1594
1595         for (psf=pmc->tomb; psf; psf=nextpsf) {
1596                 nextpsf = psf->sf_next;
1597                 kfree(psf);
1598         }
1599         pmc->tomb = NULL;
1600         for (psf=pmc->sources; psf; psf=nextpsf) {
1601                 nextpsf = psf->sf_next;
1602                 kfree(psf);
1603         }
1604         pmc->sources = NULL;
1605         pmc->sfmode = MCAST_EXCLUDE;
1606         pmc->sfcount[MCAST_EXCLUDE] = 0;
1607         pmc->sfcount[MCAST_EXCLUDE] = 1;
1608 }
1609
1610
1611 /*
1612  * Join a multicast group
1613  */
1614 int ip_mc_join_group(struct sock *sk , struct ip_mreqn *imr)
1615 {
1616         int err;
1617         u32 addr = imr->imr_multiaddr.s_addr;
1618         struct ip_mc_socklist *iml, *i;
1619         struct in_device *in_dev;
1620         struct inet_sock *inet = inet_sk(sk);
1621         int count = 0;
1622
1623         if (!MULTICAST(addr))
1624                 return -EINVAL;
1625
1626         rtnl_shlock();
1627
1628         in_dev = ip_mc_find_dev(imr);
1629
1630         if (!in_dev) {
1631                 iml = NULL;
1632                 err = -ENODEV;
1633                 goto done;
1634         }
1635
1636         iml = (struct ip_mc_socklist *)sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
1637
1638         err = -EADDRINUSE;
1639         for (i = inet->mc_list; i; i = i->next) {
1640                 if (memcmp(&i->multi, imr, sizeof(*imr)) == 0) {
1641                         /* New style additions are reference counted */
1642                         if (imr->imr_address.s_addr == 0) {
1643                                 i->count++;
1644                                 err = 0;
1645                         }
1646                         goto done;
1647                 }
1648                 count++;
1649         }
1650         err = -ENOBUFS;
1651         if (iml == NULL || count >= sysctl_igmp_max_memberships)
1652                 goto done;
1653         memcpy(&iml->multi, imr, sizeof(*imr));
1654         iml->next = inet->mc_list;
1655         iml->count = 1;
1656         iml->sflist = NULL;
1657         iml->sfmode = MCAST_EXCLUDE;
1658         inet->mc_list = iml;
1659         ip_mc_inc_group(in_dev, addr);
1660         iml = NULL;
1661         err = 0;
1662
1663 done:
1664         rtnl_shunlock();
1665         if (iml)
1666                 sock_kfree_s(sk, iml, sizeof(*iml));
1667         return err;
1668 }
1669
1670 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
1671                            struct in_device *in_dev)
1672 {
1673         int err;
1674
1675         if (iml->sflist == 0) {
1676                 /* any-source empty exclude case */
1677                 return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1678                         iml->sfmode, 0, NULL, 0);
1679         }
1680         err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1681                         iml->sfmode, iml->sflist->sl_count,
1682                         iml->sflist->sl_addr, 0);
1683         sock_kfree_s(sk, iml->sflist, IP_SFLSIZE(iml->sflist->sl_max));
1684         iml->sflist = NULL;
1685         return err;
1686 }
1687
1688 /*
1689  *      Ask a socket to leave a group.
1690  */
1691
1692 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
1693 {
1694         struct inet_sock *inet = inet_sk(sk);
1695         struct ip_mc_socklist *iml, **imlp;
1696
1697         rtnl_lock();
1698         for (imlp = &inet->mc_list; (iml = *imlp) != NULL; imlp = &iml->next) {
1699                 if (iml->multi.imr_multiaddr.s_addr==imr->imr_multiaddr.s_addr &&
1700                     iml->multi.imr_address.s_addr==imr->imr_address.s_addr &&
1701                     (!imr->imr_ifindex || iml->multi.imr_ifindex==imr->imr_ifindex)) {
1702                         struct in_device *in_dev;
1703
1704                         in_dev = inetdev_by_index(iml->multi.imr_ifindex);
1705                         if (in_dev)
1706                                 (void) ip_mc_leave_src(sk, iml, in_dev);
1707                         if (--iml->count) {
1708                                 rtnl_unlock();
1709                                 if (in_dev)
1710                                         in_dev_put(in_dev);
1711                                 return 0;
1712                         }
1713
1714                         *imlp = iml->next;
1715
1716                         if (in_dev) {
1717                                 ip_mc_dec_group(in_dev, imr->imr_multiaddr.s_addr);
1718                                 in_dev_put(in_dev);
1719                         }
1720                         rtnl_unlock();
1721                         sock_kfree_s(sk, iml, sizeof(*iml));
1722                         return 0;
1723                 }
1724         }
1725         rtnl_unlock();
1726         return -EADDRNOTAVAIL;
1727 }
1728
1729 int ip_mc_source(int add, int omode, struct sock *sk, struct
1730         ip_mreq_source *mreqs, int ifindex)
1731 {
1732         int err;
1733         struct ip_mreqn imr;
1734         u32 addr = mreqs->imr_multiaddr;
1735         struct ip_mc_socklist *pmc;
1736         struct in_device *in_dev = NULL;
1737         struct inet_sock *inet = inet_sk(sk);
1738         struct ip_sf_socklist *psl;
1739         int i, j, rv;
1740
1741         if (!MULTICAST(addr))
1742                 return -EINVAL;
1743
1744         rtnl_shlock();
1745
1746         imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
1747         imr.imr_address.s_addr = mreqs->imr_interface;
1748         imr.imr_ifindex = ifindex;
1749         in_dev = ip_mc_find_dev(&imr);
1750
1751         if (!in_dev) {
1752                 err = -ENODEV;
1753                 goto done;
1754         }
1755         err = -EADDRNOTAVAIL;
1756
1757         for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
1758                 if (memcmp(&pmc->multi, mreqs, 2*sizeof(__u32)) == 0)
1759                         break;
1760         }
1761         if (!pmc)               /* must have a prior join */
1762                 goto done;
1763         /* if a source filter was set, must be the same mode as before */
1764         if (pmc->sflist) {
1765                 if (pmc->sfmode != omode)
1766                         goto done;
1767         } else if (pmc->sfmode != omode) {
1768                 /* allow mode switches for empty-set filters */
1769                 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
1770                 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
1771                         NULL, 0);
1772                 pmc->sfmode = omode;
1773         }
1774
1775         psl = pmc->sflist;
1776         if (!add) {
1777                 if (!psl)
1778                         goto done;
1779                 rv = !0;
1780                 for (i=0; i<psl->sl_count; i++) {
1781                         rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1782                                 sizeof(__u32));
1783                         if (rv == 0)
1784                                 break;
1785                 }
1786                 if (rv)         /* source not found */
1787                         goto done;
1788
1789                 /* update the interface filter */
1790                 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1791                         &mreqs->imr_sourceaddr, 1);
1792
1793                 for (j=i+1; j<psl->sl_count; j++)
1794                         psl->sl_addr[j-1] = psl->sl_addr[j];
1795                 psl->sl_count--;
1796                 err = 0;
1797                 goto done;
1798         }
1799         /* else, add a new source to the filter */
1800
1801         if (psl && psl->sl_count >= sysctl_igmp_max_msf) {
1802                 err = -ENOBUFS;
1803                 goto done;
1804         }
1805         if (!psl || psl->sl_count == psl->sl_max) {
1806                 struct ip_sf_socklist *newpsl;
1807                 int count = IP_SFBLOCK;
1808
1809                 if (psl)
1810                         count += psl->sl_max;
1811                 newpsl = (struct ip_sf_socklist *)sock_kmalloc(sk,
1812                         IP_SFLSIZE(count), GFP_KERNEL);
1813                 if (!newpsl) {
1814                         err = -ENOBUFS;
1815                         goto done;
1816                 }
1817                 newpsl->sl_max = count;
1818                 newpsl->sl_count = count - IP_SFBLOCK;
1819                 if (psl) {
1820                         for (i=0; i<psl->sl_count; i++)
1821                                 newpsl->sl_addr[i] = psl->sl_addr[i];
1822                         sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
1823                 }
1824                 pmc->sflist = psl = newpsl;
1825         }
1826         rv = 1; /* > 0 for insert logic below if sl_count is 0 */
1827         for (i=0; i<psl->sl_count; i++) {
1828                 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
1829                         sizeof(__u32));
1830                 if (rv == 0)
1831                         break;
1832         }
1833         if (rv == 0)            /* address already there is an error */
1834                 goto done;
1835         for (j=psl->sl_count-1; j>=i; j--)
1836                 psl->sl_addr[j+1] = psl->sl_addr[j];
1837         psl->sl_addr[i] = mreqs->imr_sourceaddr;
1838         psl->sl_count++;
1839         err = 0;
1840         /* update the interface list */
1841         ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
1842                 &mreqs->imr_sourceaddr, 1);
1843 done:
1844         rtnl_shunlock();
1845         return err;
1846 }
1847
1848 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
1849 {
1850         int err;
1851         struct ip_mreqn imr;
1852         u32 addr = msf->imsf_multiaddr;
1853         struct ip_mc_socklist *pmc;
1854         struct in_device *in_dev;
1855         struct inet_sock *inet = inet_sk(sk);
1856         struct ip_sf_socklist *newpsl, *psl;
1857
1858         if (!MULTICAST(addr))
1859                 return -EINVAL;
1860         if (msf->imsf_fmode != MCAST_INCLUDE &&
1861             msf->imsf_fmode != MCAST_EXCLUDE)
1862                 return -EINVAL;
1863
1864         rtnl_shlock();
1865
1866         imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
1867         imr.imr_address.s_addr = msf->imsf_interface;
1868         imr.imr_ifindex = ifindex;
1869         in_dev = ip_mc_find_dev(&imr);
1870
1871         if (!in_dev) {
1872                 err = -ENODEV;
1873                 goto done;
1874         }
1875         err = -EADDRNOTAVAIL;
1876
1877         for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
1878                 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
1879                     pmc->multi.imr_ifindex == imr.imr_ifindex)
1880                         break;
1881         }
1882         if (!pmc)               /* must have a prior join */
1883                 goto done;
1884         if (msf->imsf_numsrc) {
1885                 newpsl = (struct ip_sf_socklist *)sock_kmalloc(sk,
1886                                 IP_SFLSIZE(msf->imsf_numsrc), GFP_KERNEL);
1887                 if (!newpsl) {
1888                         err = -ENOBUFS;
1889                         goto done;
1890                 }
1891                 newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
1892                 memcpy(newpsl->sl_addr, msf->imsf_slist,
1893                         msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
1894                 err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
1895                         msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
1896                 if (err) {
1897                         sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
1898                         goto done;
1899                 }
1900         } else
1901                 newpsl = NULL;
1902         psl = pmc->sflist;
1903         if (psl) {
1904                 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
1905                         psl->sl_count, psl->sl_addr, 0);
1906                 sock_kfree_s(sk, psl, IP_SFLSIZE(psl->sl_max));
1907         } else
1908                 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
1909                         0, NULL, 0);
1910         pmc->sflist = newpsl;
1911         pmc->sfmode = msf->imsf_fmode;
1912 done:
1913         rtnl_shunlock();
1914         return err;
1915 }
1916
1917 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
1918         struct ip_msfilter __user *optval, int __user *optlen)
1919 {
1920         int err, len, count, copycount;
1921         struct ip_mreqn imr;
1922         u32 addr = msf->imsf_multiaddr;
1923         struct ip_mc_socklist *pmc;
1924         struct in_device *in_dev;
1925         struct inet_sock *inet = inet_sk(sk);
1926         struct ip_sf_socklist *psl;
1927
1928         if (!MULTICAST(addr))
1929                 return -EINVAL;
1930
1931         rtnl_shlock();
1932
1933         imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
1934         imr.imr_address.s_addr = msf->imsf_interface;
1935         imr.imr_ifindex = 0;
1936         in_dev = ip_mc_find_dev(&imr);
1937
1938         if (!in_dev) {
1939                 err = -ENODEV;
1940                 goto done;
1941         }
1942         err = -EADDRNOTAVAIL;
1943
1944         for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
1945                 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
1946                     pmc->multi.imr_ifindex == imr.imr_ifindex)
1947                         break;
1948         }
1949         if (!pmc)               /* must have a prior join */
1950                 goto done;
1951         msf->imsf_fmode = pmc->sfmode;
1952         psl = pmc->sflist;
1953         rtnl_shunlock();
1954         if (!psl) {
1955                 len = 0;
1956                 count = 0;
1957         } else {
1958                 count = psl->sl_count;
1959         }
1960         copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
1961         len = copycount * sizeof(psl->sl_addr[0]);
1962         msf->imsf_numsrc = count;
1963         if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
1964             copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
1965                 return -EFAULT;
1966         }
1967         if (len &&
1968             copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
1969                 return -EFAULT;
1970         return 0;
1971 done:
1972         rtnl_shunlock();
1973         return err;
1974 }
1975
1976 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
1977         struct group_filter __user *optval, int __user *optlen)
1978 {
1979         int err, i, count, copycount;
1980         struct sockaddr_in *psin;
1981         u32 addr;
1982         struct ip_mc_socklist *pmc;
1983         struct inet_sock *inet = inet_sk(sk);
1984         struct ip_sf_socklist *psl;
1985
1986         psin = (struct sockaddr_in *)&gsf->gf_group;
1987         if (psin->sin_family != AF_INET)
1988                 return -EINVAL;
1989         addr = psin->sin_addr.s_addr;
1990         if (!MULTICAST(addr))
1991                 return -EINVAL;
1992
1993         rtnl_shlock();
1994
1995         err = -EADDRNOTAVAIL;
1996
1997         for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
1998                 if (pmc->multi.imr_multiaddr.s_addr == addr &&
1999                     pmc->multi.imr_ifindex == gsf->gf_interface)
2000                         break;
2001         }
2002         if (!pmc)               /* must have a prior join */
2003                 goto done;
2004         gsf->gf_fmode = pmc->sfmode;
2005         psl = pmc->sflist;
2006         rtnl_shunlock();
2007         count = psl ? psl->sl_count : 0;
2008         copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2009         gsf->gf_numsrc = count;
2010         if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2011             copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2012                 return -EFAULT;
2013         }
2014         for (i=0; i<copycount; i++) {
2015                 struct sockaddr_in *psin;
2016                 struct sockaddr_storage ss;
2017
2018                 psin = (struct sockaddr_in *)&ss;
2019                 memset(&ss, 0, sizeof(ss));
2020                 psin->sin_family = AF_INET;
2021                 psin->sin_addr.s_addr = psl->sl_addr[i];
2022                 if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2023                         return -EFAULT;
2024         }
2025         return 0;
2026 done:
2027         rtnl_shunlock();
2028         return err;
2029 }
2030
2031 /*
2032  * check if a multicast source filter allows delivery for a given <src,dst,intf>
2033  */
2034 int ip_mc_sf_allow(struct sock *sk, u32 loc_addr, u32 rmt_addr, int dif)
2035 {
2036         struct inet_sock *inet = inet_sk(sk);
2037         struct ip_mc_socklist *pmc;
2038         struct ip_sf_socklist *psl;
2039         int i;
2040
2041         if (!MULTICAST(loc_addr))
2042                 return 1;
2043
2044         for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
2045                 if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2046                     pmc->multi.imr_ifindex == dif)
2047                         break;
2048         }
2049         if (!pmc)
2050                 return 1;
2051         psl = pmc->sflist;
2052         if (!psl)
2053                 return pmc->sfmode == MCAST_EXCLUDE;
2054
2055         for (i=0; i<psl->sl_count; i++) {
2056                 if (psl->sl_addr[i] == rmt_addr)
2057                         break;
2058         }
2059         if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2060                 return 0;
2061         if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2062                 return 0;
2063         return 1;
2064 }
2065
2066 /*
2067  *      A socket is closing.
2068  */
2069
2070 void ip_mc_drop_socket(struct sock *sk)
2071 {
2072         struct inet_sock *inet = inet_sk(sk);
2073         struct ip_mc_socklist *iml;
2074
2075         if (inet->mc_list == NULL)
2076                 return;
2077
2078         rtnl_lock();
2079         while ((iml = inet->mc_list) != NULL) {
2080                 struct in_device *in_dev;
2081                 inet->mc_list = iml->next;
2082
2083                 if ((in_dev = inetdev_by_index(iml->multi.imr_ifindex)) != NULL) {
2084                         (void) ip_mc_leave_src(sk, iml, in_dev);
2085                         ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2086                         in_dev_put(in_dev);
2087                 }
2088                 sock_kfree_s(sk, iml, sizeof(*iml));
2089
2090         }
2091         rtnl_unlock();
2092 }
2093
2094 int ip_check_mc(struct in_device *in_dev, u32 mc_addr, u32 src_addr, u16 proto)
2095 {
2096         struct ip_mc_list *im;
2097         struct ip_sf_list *psf;
2098         int rv = 0;
2099
2100         read_lock(&in_dev->mc_list_lock);
2101         for (im=in_dev->mc_list; im; im=im->next) {
2102                 if (im->multiaddr == mc_addr)
2103                         break;
2104         }
2105         if (im && proto == IPPROTO_IGMP) {
2106                 rv = 1;
2107         } else if (im) {
2108                 if (src_addr) {
2109                         for (psf=im->sources; psf; psf=psf->sf_next) {
2110                                 if (psf->sf_inaddr == src_addr)
2111                                         break;
2112                         }
2113                         if (psf)
2114                                 rv = psf->sf_count[MCAST_INCLUDE] ||
2115                                         psf->sf_count[MCAST_EXCLUDE] !=
2116                                         im->sfcount[MCAST_EXCLUDE];
2117                         else
2118                                 rv = im->sfcount[MCAST_EXCLUDE] != 0;
2119                 } else
2120                         rv = 1; /* unspecified source; tentatively allow */
2121         }
2122         read_unlock(&in_dev->mc_list_lock);
2123         return rv;
2124 }
2125
2126 #if defined(CONFIG_PROC_FS)
2127 struct igmp_mc_iter_state {
2128         struct net_device *dev;
2129         struct in_device *in_dev;
2130 };
2131
2132 #define igmp_mc_seq_private(seq)        ((struct igmp_mc_iter_state *)(seq)->private)
2133
2134 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2135 {
2136         struct ip_mc_list *im = NULL;
2137         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2138
2139         for (state->dev = dev_base, state->in_dev = NULL;
2140              state->dev;
2141              state->dev = state->dev->next) {
2142                 struct in_device *in_dev;
2143                 in_dev = in_dev_get(state->dev);
2144                 if (!in_dev)
2145                         continue;
2146                 read_lock(&in_dev->mc_list_lock);
2147                 im = in_dev->mc_list;
2148                 if (im) {
2149                         state->in_dev = in_dev;
2150                         break;
2151                 }
2152                 read_unlock(&in_dev->mc_list_lock);
2153                 in_dev_put(in_dev);
2154         }
2155         return im;
2156 }
2157
2158 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2159 {
2160         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2161         im = im->next;
2162         while (!im) {
2163                 if (likely(state->in_dev != NULL)) {
2164                         read_unlock(&state->in_dev->mc_list_lock);
2165                         in_dev_put(state->in_dev);
2166                 }
2167                 state->dev = state->dev->next;
2168                 if (!state->dev) {
2169                         state->in_dev = NULL;
2170                         break;
2171                 }
2172                 state->in_dev = in_dev_get(state->dev);
2173                 if (!state->in_dev)
2174                         continue;
2175                 read_lock(&state->in_dev->mc_list_lock);
2176                 im = state->in_dev->mc_list;
2177         }
2178         return im;
2179 }
2180
2181 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2182 {
2183         struct ip_mc_list *im = igmp_mc_get_first(seq);
2184         if (im)
2185                 while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2186                         --pos;
2187         return pos ? NULL : im;
2188 }
2189
2190 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2191 {
2192         read_lock(&dev_base_lock);
2193         return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2194 }
2195
2196 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2197 {
2198         struct ip_mc_list *im;
2199         if (v == SEQ_START_TOKEN)
2200                 im = igmp_mc_get_first(seq);
2201         else
2202                 im = igmp_mc_get_next(seq, v);
2203         ++*pos;
2204         return im;
2205 }
2206
2207 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2208 {
2209         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2210         if (likely(state->in_dev != NULL)) {
2211                 read_unlock(&state->in_dev->mc_list_lock);
2212                 in_dev_put(state->in_dev);
2213                 state->in_dev = NULL;
2214         }
2215         state->dev = NULL;
2216         read_unlock(&dev_base_lock);
2217 }
2218
2219 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2220 {
2221         if (v == SEQ_START_TOKEN)
2222                 seq_puts(seq,
2223                          "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2224         else {
2225                 struct ip_mc_list *im = (struct ip_mc_list *)v;
2226                 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2227                 char   *querier;
2228 #ifdef CONFIG_IP_MULTICAST
2229                 querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2230                           IGMP_V2_SEEN(state->in_dev) ? "V2" :
2231                           "V3";
2232 #else
2233                 querier = "NONE";
2234 #endif
2235
2236                 if (state->in_dev->mc_list == im) {
2237                         seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2238                                    state->dev->ifindex, state->dev->name, state->dev->mc_count, querier);
2239                 }
2240
2241                 seq_printf(seq,
2242                            "\t\t\t\t%08lX %5d %d:%08lX\t\t%d\n",
2243                            im->multiaddr, im->users,
2244                            im->tm_running, im->tm_running ?
2245                            jiffies_to_clock_t(im->timer.expires-jiffies) : 0,
2246                            im->reporter);
2247         }
2248         return 0;
2249 }
2250
2251 static struct seq_operations igmp_mc_seq_ops = {
2252         .start  =       igmp_mc_seq_start,
2253         .next   =       igmp_mc_seq_next,
2254         .stop   =       igmp_mc_seq_stop,
2255         .show   =       igmp_mc_seq_show,
2256 };
2257
2258 static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2259 {
2260         struct seq_file *seq;
2261         int rc = -ENOMEM;
2262         struct igmp_mc_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL);
2263
2264         if (!s)
2265                 goto out;
2266         rc = seq_open(file, &igmp_mc_seq_ops);
2267         if (rc)
2268                 goto out_kfree;
2269
2270         seq = file->private_data;
2271         seq->private = s;
2272         memset(s, 0, sizeof(*s));
2273 out:
2274         return rc;
2275 out_kfree:
2276         kfree(s);
2277         goto out;
2278 }
2279
2280 static struct file_operations igmp_mc_seq_fops = {
2281         .owner          =       THIS_MODULE,
2282         .open           =       igmp_mc_seq_open,
2283         .read           =       seq_read,
2284         .llseek         =       seq_lseek,
2285         .release        =       seq_release_private,
2286 };
2287
2288 struct igmp_mcf_iter_state {
2289         struct net_device *dev;
2290         struct in_device *idev;
2291         struct ip_mc_list *im;
2292 };
2293
2294 #define igmp_mcf_seq_private(seq)       ((struct igmp_mcf_iter_state *)(seq)->private)
2295
2296 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2297 {
2298         struct ip_sf_list *psf = NULL;
2299         struct ip_mc_list *im = NULL;
2300         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2301
2302         for (state->dev = dev_base, state->idev = NULL, state->im = NULL;
2303              state->dev;
2304              state->dev = state->dev->next) {
2305                 struct in_device *idev;
2306                 idev = in_dev_get(state->dev);
2307                 if (unlikely(idev == NULL))
2308                         continue;
2309                 read_lock(&idev->mc_list_lock);
2310                 im = idev->mc_list;
2311                 if (likely(im != NULL)) {
2312                         spin_lock_bh(&im->lock);
2313                         psf = im->sources;
2314                         if (likely(psf != NULL)) {
2315                                 state->im = im;
2316                                 state->idev = idev;
2317                                 break;
2318                         }
2319                         spin_unlock_bh(&im->lock);
2320                 }
2321                 read_unlock(&idev->mc_list_lock);
2322                 in_dev_put(idev);
2323         }
2324         return psf;
2325 }
2326
2327 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2328 {
2329         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2330
2331         psf = psf->sf_next;
2332         while (!psf) {
2333                 spin_unlock_bh(&state->im->lock);
2334                 state->im = state->im->next;
2335                 while (!state->im) {
2336                         if (likely(state->idev != NULL)) {
2337                                 read_unlock(&state->idev->mc_list_lock);
2338                                 in_dev_put(state->idev);
2339                         }
2340                         state->dev = state->dev->next;
2341                         if (!state->dev) {
2342                                 state->idev = NULL;
2343                                 goto out;
2344                         }
2345                         state->idev = in_dev_get(state->dev);
2346                         if (!state->idev)
2347                                 continue;
2348                         read_lock(&state->idev->mc_list_lock);
2349                         state->im = state->idev->mc_list;
2350                 }
2351                 if (!state->im)
2352                         break;
2353                 spin_lock_bh(&state->im->lock);
2354                 psf = state->im->sources;
2355         }
2356 out:
2357         return psf;
2358 }
2359
2360 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2361 {
2362         struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2363         if (psf)
2364                 while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2365                         --pos;
2366         return pos ? NULL : psf;
2367 }
2368
2369 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2370 {
2371         read_lock(&dev_base_lock);
2372         return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2373 }
2374
2375 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2376 {
2377         struct ip_sf_list *psf;
2378         if (v == SEQ_START_TOKEN)
2379                 psf = igmp_mcf_get_first(seq);
2380         else
2381                 psf = igmp_mcf_get_next(seq, v);
2382         ++*pos;
2383         return psf;
2384 }
2385
2386 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2387 {
2388         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2389         if (likely(state->im != NULL)) {
2390                 spin_unlock_bh(&state->im->lock);
2391                 state->im = NULL;
2392         }
2393         if (likely(state->idev != NULL)) {
2394                 read_unlock(&state->idev->mc_list_lock);
2395                 in_dev_put(state->idev);
2396                 state->idev = NULL;
2397         }
2398         state->dev = NULL;
2399         read_unlock(&dev_base_lock);
2400 }
2401
2402 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2403 {
2404         struct ip_sf_list *psf = (struct ip_sf_list *)v;
2405         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2406
2407         if (v == SEQ_START_TOKEN) {
2408                 seq_printf(seq,
2409                            "%3s %6s "
2410                            "%10s %10s %6s %6s\n", "Idx",
2411                            "Device", "MCA",
2412                            "SRC", "INC", "EXC");
2413         } else {
2414                 seq_printf(seq,
2415                            "%3d %6.6s 0x%08x "
2416                            "0x%08x %6lu %6lu\n",
2417                            state->dev->ifindex, state->dev->name,
2418                            ntohl(state->im->multiaddr),
2419                            ntohl(psf->sf_inaddr),
2420                            psf->sf_count[MCAST_INCLUDE],
2421                            psf->sf_count[MCAST_EXCLUDE]);
2422         }
2423         return 0;
2424 }
2425
2426 static struct seq_operations igmp_mcf_seq_ops = {
2427         .start  =       igmp_mcf_seq_start,
2428         .next   =       igmp_mcf_seq_next,
2429         .stop   =       igmp_mcf_seq_stop,
2430         .show   =       igmp_mcf_seq_show,
2431 };
2432
2433 static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2434 {
2435         struct seq_file *seq;
2436         int rc = -ENOMEM;
2437         struct igmp_mcf_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL);
2438
2439         if (!s)
2440                 goto out;
2441         rc = seq_open(file, &igmp_mcf_seq_ops);
2442         if (rc)
2443                 goto out_kfree;
2444
2445         seq = file->private_data;
2446         seq->private = s;
2447         memset(s, 0, sizeof(*s));
2448 out:
2449         return rc;
2450 out_kfree:
2451         kfree(s);
2452         goto out;
2453 }
2454
2455 static struct file_operations igmp_mcf_seq_fops = {
2456         .owner          =       THIS_MODULE,
2457         .open           =       igmp_mcf_seq_open,
2458         .read           =       seq_read,
2459         .llseek         =       seq_lseek,
2460         .release        =       seq_release_private,
2461 };
2462
2463 int __init igmp_mc_proc_init(void)
2464 {
2465         proc_net_fops_create("igmp", S_IRUGO, &igmp_mc_seq_fops);
2466         proc_net_fops_create("mcfilter", S_IRUGO, &igmp_mcf_seq_fops);
2467         return 0;
2468 }
2469 #endif
2470
2471 EXPORT_SYMBOL(ip_mc_dec_group);
2472 EXPORT_SYMBOL(ip_mc_inc_group);
2473 EXPORT_SYMBOL(ip_mc_join_group);