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  *      Authors:
  12  *              Alan Cox <alan@lxorguk.ukuu.org.uk>
  13  *
  14  *      This program is free software; you can redistribute it and/or
  15  *      modify it under the terms of the GNU General Public License
  16  *      as published by the Free Software Foundation; either version
  17  *      2 of the License, or (at your option) any later version.
  18  *
  19  *      Fixes:
  20  *
  21  *              Alan Cox        :       Added lots of __inline__ to optimise
  22  *                                      the memory usage of all the tiny little
  23  *                                      functions.
  24  *              Alan Cox        :       Dumped the header building experiment.
  25  *              Alan Cox        :       Minor tweaks ready for multicast routing
  26  *                                      and extended IGMP protocol.
  27  *              Alan Cox        :       Removed a load of inline directives. Gcc 2.5.8
  28  *                                      writes utterly bogus code otherwise (sigh)
  29  *                                      fixed IGMP loopback to behave in the manner
  30  *                                      desired by mrouted, fixed the fact it has been
  31  *                                      broken since 1.3.6 and cleaned up a few minor
  32  *                                      points.
  33  *
  34  *              Chih-Jen Chang  :       Tried to revise IGMP to Version 2
  35  *              Tsu-Sheng Tsao          E-mail: chihjenc@scf.usc.edu and tsusheng@scf.usc.edu
  36  *                                      The enhancements are mainly based on Steve Deering's
  37  *                                      ipmulti-3.5 source code.
  38  *              Chih-Jen Chang  :       Added the igmp_get_mrouter_info and
  39  *              Tsu-Sheng Tsao          igmp_set_mrouter_info to keep track of
  40  *                                      the mrouted version on that device.
  41  *              Chih-Jen Chang  :       Added the max_resp_time parameter to
  42  *              Tsu-Sheng Tsao          igmp_heard_query(). Using this parameter
  43  *                                      to identify the multicast router version
  44  *                                      and do what the IGMP version 2 specified.
  45  *              Chih-Jen Chang  :       Added a timer to revert to IGMP V2 router
  46  *              Tsu-Sheng Tsao          if the specified time expired.
  47  *              Alan Cox        :       Stop IGMP from 0.0.0.0 being accepted.
  48  *              Alan Cox        :       Use GFP_ATOMIC in the right places.
  49  *              Christian Daudt :       igmp timer wasn't set for local group
  50  *                                      memberships but was being deleted,
  51  *                                      which caused a "del_timer() called
  52  *                                      from %p with timer not initialized\n"
  53  *                                      message (960131).
  54  *              Christian Daudt :       removed del_timer from
  55  *                                      igmp_timer_expire function (960205).
  56  *             Christian Daudt :       igmp_heard_report now only calls
  57  *                                     igmp_timer_expire if tm->running is
  58  *                                     true (960216).
  59  *              Malcolm Beattie :       ttl comparison wrong in igmp_rcv made
  60  *                                      igmp_heard_query never trigger. Expiry
  61  *                                      miscalculation fixed in igmp_heard_query
  62  *                                      and random() made to return unsigned to
  63  *                                      prevent negative expiry times.
  64  *              Alexey Kuznetsov:       Wrong group leaving behaviour, backport
  65  *                                      fix from pending 2.1.x patches.
  66  *              Alan Cox:               Forget to enable FDDI support earlier.
  67  *              Alexey Kuznetsov:       Fixed leaving groups on device down.
  68  *              Alexey Kuznetsov:       Accordance to igmp-v2-06 draft.
  69  *              David L Stevens:        IGMPv3 support, with help from
  70  *                                      Vinay Kulkarni
  71  */
  72
  73 #include <linux/module.h>
  74 #include <linux/slab.h>
  75 #include <asm/uaccess.h>
  76 #include <linux/types.h>
  77 #include <linux/kernel.h>
  78 #include <linux/jiffies.h>
  79 #include <linux/string.h>
  80 #include <linux/socket.h>
  81 #include <linux/sockios.h>
  82 #include <linux/in.h>
  83 #include <linux/inet.h>
  84 #include <linux/netdevice.h>
  85 #include <linux/skbuff.h>
  86 #include <linux/inetdevice.h>
  87 #include <linux/igmp.h>
  88 #include <linux/if_arp.h>
  89 #include <linux/rtnetlink.h>
  90 #include <linux/times.h>
  91 #include <linux/pkt_sched.h>
  92
  93 #include <net/net_namespace.h>
  94 #include <net/arp.h>
  95 #include <net/ip.h>
  96 #include <net/protocol.h>
  97 #include <net/route.h>
  98 #include <net/sock.h>
  99 #include <net/checksum.h>
 100 #include <linux/netfilter_ipv4.h>
 101 #ifdef CONFIG_IP_MROUTE
 102 #include <linux/mroute.h>
 103 #endif
 104 #ifdef CONFIG_PROC_FS
 105 #include <linux/proc_fs.h>
 106 #include <linux/seq_file.h>
 107 #endif
 108
 109 #define IP_MAX_MEMBERSHIPS      20
 110 #define IP_MAX_MSF              10
 111
 112 #ifdef CONFIG_IP_MULTICAST
 113 /* Parameter names and values are taken from igmp-v2-06 draft */
 114
 115 #define IGMP_V1_Router_Present_Timeout          (400*HZ)
 116 #define IGMP_V2_Router_Present_Timeout          (400*HZ)
 117 #define IGMP_V2_Unsolicited_Report_Interval     (10*HZ)
 118 #define IGMP_V3_Unsolicited_Report_Interval     (1*HZ)
 119 #define IGMP_Query_Response_Interval            (10*HZ)
 120 #define IGMP_Query_Robustness_Variable          2
 121
 122
 123 #define IGMP_Initial_Report_Delay               (1)
 124
 125 /* IGMP_Initial_Report_Delay is not from IGMP specs!
 126  * IGMP specs require to report membership immediately after
 127  * joining a group, but we delay the first report by a
 128  * small interval. It seems more natural and still does not
 129  * contradict to specs provided this delay is small enough.
 130  */
 131
 132 #define IGMP_V1_SEEN(in_dev) \
 133         (IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \
 134          IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \
 135          ((in_dev)->mr_v1_seen && \
 136           time_before(jiffies, (in_dev)->mr_v1_seen)))
 137 #define IGMP_V2_SEEN(in_dev) \
 138         (IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \
 139          IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \
 140          ((in_dev)->mr_v2_seen && \
 141           time_before(jiffies, (in_dev)->mr_v2_seen)))
 142
 143 static int unsolicited_report_interval(struct in_device *in_dev)
 144 {
 145         int interval_ms, interval_jiffies;
 146
 147         if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 148                 interval_ms = IN_DEV_CONF_GET(
 149                         in_dev,
 150                         IGMPV2_UNSOLICITED_REPORT_INTERVAL);
 151         else /* v3 */
 152                 interval_ms = IN_DEV_CONF_GET(
 153                         in_dev,
 154                         IGMPV3_UNSOLICITED_REPORT_INTERVAL);
 155
 156         interval_jiffies = msecs_to_jiffies(interval_ms);
 157
 158         /* _timer functions can't handle a delay of 0 jiffies so ensure
 159          *  we always return a positive value.
 160          */
 161         if (interval_jiffies <= 0)
 162                 interval_jiffies = 1;
 163         return interval_jiffies;
 164 }
 165
 166 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im);
 167 static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr);
 168 static void igmpv3_clear_delrec(struct in_device *in_dev);
 169 static int sf_setstate(struct ip_mc_list *pmc);
 170 static void sf_markstate(struct ip_mc_list *pmc);
 171 #endif
 172 static void ip_mc_clear_src(struct ip_mc_list *pmc);
 173 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
 174                          int sfcount, __be32 *psfsrc, int delta);
 175
 176 static void ip_ma_put(struct ip_mc_list *im)
 177 {
 178         if (atomic_dec_and_test(&im->refcnt)) {
 179                 in_dev_put(im->interface);
 180                 kfree_rcu(im, rcu);
 181         }
 182 }
 183
 184 #define for_each_pmc_rcu(in_dev, pmc)                           \
 185         for (pmc = rcu_dereference(in_dev->mc_list);            \
 186              pmc != NULL;                                       \
 187              pmc = rcu_dereference(pmc->next_rcu))
 188
 189 #define for_each_pmc_rtnl(in_dev, pmc)                          \
 190         for (pmc = rtnl_dereference(in_dev->mc_list);           \
 191              pmc != NULL;                                       \
 192              pmc = rtnl_dereference(pmc->next_rcu))
 193
 194 #ifdef CONFIG_IP_MULTICAST
 195
 196 /*
 197  *      Timer management
 198  */
 199
 200 static void igmp_stop_timer(struct ip_mc_list *im)
 201 {
 202         spin_lock_bh(&im->lock);
 203         if (del_timer(&im->timer))
 204                 atomic_dec(&im->refcnt);
 205         im->tm_running = 0;
 206         im->reporter = 0;
 207         im->unsolicit_count = 0;
 208         spin_unlock_bh(&im->lock);
 209 }
 210
 211 /* It must be called with locked im->lock */
 212 static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
 213 {
 214         int tv = prandom_u32() % max_delay;
 215
 216         im->tm_running = 1;
 217         if (!mod_timer(&im->timer, jiffies+tv+2))
 218                 atomic_inc(&im->refcnt);
 219 }
 220
 221 static void igmp_gq_start_timer(struct in_device *in_dev)
 222 {
 223         int tv = prandom_u32() % in_dev->mr_maxdelay;
 224
 225         in_dev->mr_gq_running = 1;
 226         if (!mod_timer(&in_dev->mr_gq_timer, jiffies+tv+2))
 227                 in_dev_hold(in_dev);
 228 }
 229
 230 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
 231 {
 232         int tv = prandom_u32() % delay;
 233
 234         if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
 235                 in_dev_hold(in_dev);
 236 }
 237
 238 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
 239 {
 240         spin_lock_bh(&im->lock);
 241         im->unsolicit_count = 0;
 242         if (del_timer(&im->timer)) {
 243                 if ((long)(im->timer.expires-jiffies) < max_delay) {
 244                         add_timer(&im->timer);
 245                         im->tm_running = 1;
 246                         spin_unlock_bh(&im->lock);
 247                         return;
 248                 }
 249                 atomic_dec(&im->refcnt);
 250         }
 251         igmp_start_timer(im, max_delay);
 252         spin_unlock_bh(&im->lock);
 253 }
 254
 255
 256 /*
 257  *      Send an IGMP report.
 258  */
 259
 260 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
 261
 262
 263 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
 264         int gdeleted, int sdeleted)
 265 {
 266         switch (type) {
 267         case IGMPV3_MODE_IS_INCLUDE:
 268         case IGMPV3_MODE_IS_EXCLUDE:
 269                 if (gdeleted || sdeleted)
 270                         return 0;
 271                 if (!(pmc->gsquery && !psf->sf_gsresp)) {
 272                         if (pmc->sfmode == MCAST_INCLUDE)
 273                                 return 1;
 274                         /* don't include if this source is excluded
 275                          * in all filters
 276                          */
 277                         if (psf->sf_count[MCAST_INCLUDE])
 278                                 return type == IGMPV3_MODE_IS_INCLUDE;
 279                         return pmc->sfcount[MCAST_EXCLUDE] ==
 280                                 psf->sf_count[MCAST_EXCLUDE];
 281                 }
 282                 return 0;
 283         case IGMPV3_CHANGE_TO_INCLUDE:
 284                 if (gdeleted || sdeleted)
 285                         return 0;
 286                 return psf->sf_count[MCAST_INCLUDE] != 0;
 287         case IGMPV3_CHANGE_TO_EXCLUDE:
 288                 if (gdeleted || sdeleted)
 289                         return 0;
 290                 if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
 291                     psf->sf_count[MCAST_INCLUDE])
 292                         return 0;
 293                 return pmc->sfcount[MCAST_EXCLUDE] ==
 294                         psf->sf_count[MCAST_EXCLUDE];
 295         case IGMPV3_ALLOW_NEW_SOURCES:
 296                 if (gdeleted || !psf->sf_crcount)
 297                         return 0;
 298                 return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
 299         case IGMPV3_BLOCK_OLD_SOURCES:
 300                 if (pmc->sfmode == MCAST_INCLUDE)
 301                         return gdeleted || (psf->sf_crcount && sdeleted);
 302                 return psf->sf_crcount && !gdeleted && !sdeleted;
 303         }
 304         return 0;
 305 }
 306
 307 static int
 308 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
 309 {
 310         struct ip_sf_list *psf;
 311         int scount = 0;
 312
 313         for (psf = pmc->sources; psf; psf = psf->sf_next) {
 314                 if (!is_in(pmc, psf, type, gdeleted, sdeleted))
 315                         continue;
 316                 scount++;
 317         }
 318         return scount;
 319 }
 320
 321 static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
 322 {
 323         struct sk_buff *skb;
 324         struct rtable *rt;
 325         struct iphdr *pip;
 326         struct igmpv3_report *pig;
 327         struct net *net = dev_net(dev);
 328         struct flowi4 fl4;
 329         int hlen = LL_RESERVED_SPACE(dev);
 330         int tlen = dev->needed_tailroom;
 331         unsigned int size = mtu;
 332
 333         while (1) {
 334                 skb = alloc_skb(size + hlen + tlen,
 335                                 GFP_ATOMIC | __GFP_NOWARN);
 336                 if (skb)
 337                         break;
 338                 size >>= 1;
 339                 if (size < 256)
 340                         return NULL;
 341         }
 342         skb->priority = TC_PRIO_CONTROL;
 343
 344         rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0,
 345                                    0, 0,
 346                                    IPPROTO_IGMP, 0, dev->ifindex);
 347         if (IS_ERR(rt)) {
 348                 kfree_skb(skb);
 349                 return NULL;
 350         }
 351
 352         skb_dst_set(skb, &rt->dst);
 353         skb->dev = dev;
 354
 355         skb->reserved_tailroom = skb_end_offset(skb) -
 356                                  min(mtu, skb_end_offset(skb));
 357         skb_reserve(skb, hlen);
 358
 359         skb_reset_network_header(skb);
 360         pip = ip_hdr(skb);
 361         skb_put(skb, sizeof(struct iphdr) + 4);
 362
 363         pip->version  = 4;
 364         pip->ihl      = (sizeof(struct iphdr)+4)>>2;
 365         pip->tos      = 0xc0;
 366         pip->frag_off = htons(IP_DF);
 367         pip->ttl      = 1;
 368         pip->daddr    = fl4.daddr;
 369         pip->saddr    = fl4.saddr;
 370         pip->protocol = IPPROTO_IGMP;
 371         pip->tot_len  = 0;      /* filled in later */
 372         ip_select_ident(skb, NULL);
 373         ((u8 *)&pip[1])[0] = IPOPT_RA;
 374         ((u8 *)&pip[1])[1] = 4;
 375         ((u8 *)&pip[1])[2] = 0;
 376         ((u8 *)&pip[1])[3] = 0;
 377
 378         skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
 379         skb_put(skb, sizeof(*pig));
 380         pig = igmpv3_report_hdr(skb);
 381         pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
 382         pig->resv1 = 0;
 383         pig->csum = 0;
 384         pig->resv2 = 0;
 385         pig->ngrec = 0;
 386         return skb;
 387 }
 388
 389 static int igmpv3_sendpack(struct sk_buff *skb)
 390 {
 391         struct igmphdr *pig = igmp_hdr(skb);
 392         const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
 393
 394         pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
 395
 396         return ip_local_out(skb);
 397 }
 398
 399 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
 400 {
 401         return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
 402 }
 403
 404 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
 405         int type, struct igmpv3_grec **ppgr)
 406 {
 407         struct net_device *dev = pmc->interface->dev;
 408         struct igmpv3_report *pih;
 409         struct igmpv3_grec *pgr;
 410
 411         if (!skb)
 412                 skb = igmpv3_newpack(dev, dev->mtu);
 413         if (!skb)
 414                 return NULL;
 415         pgr = (struct igmpv3_grec *)skb_put(skb, sizeof(struct igmpv3_grec));
 416         pgr->grec_type = type;
 417         pgr->grec_auxwords = 0;
 418         pgr->grec_nsrcs = 0;
 419         pgr->grec_mca = pmc->multiaddr;
 420         pih = igmpv3_report_hdr(skb);
 421         pih->ngrec = htons(ntohs(pih->ngrec)+1);
 422         *ppgr = pgr;
 423         return skb;
 424 }
 425
 426 #define AVAILABLE(skb)  ((skb) ? skb_availroom(skb) : 0)
 427
 428 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
 429         int type, int gdeleted, int sdeleted)
 430 {
 431         struct net_device *dev = pmc->interface->dev;
 432         struct igmpv3_report *pih;
 433         struct igmpv3_grec *pgr = NULL;
 434         struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
 435         int scount, stotal, first, isquery, truncate;
 436
 437         if (pmc->multiaddr == IGMP_ALL_HOSTS)
 438                 return skb;
 439
 440         isquery = type == IGMPV3_MODE_IS_INCLUDE ||
 441                   type == IGMPV3_MODE_IS_EXCLUDE;
 442         truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
 443                     type == IGMPV3_CHANGE_TO_EXCLUDE;
 444
 445         stotal = scount = 0;
 446
 447         psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
 448
 449         if (!*psf_list)
 450                 goto empty_source;
 451
 452         pih = skb ? igmpv3_report_hdr(skb) : NULL;
 453
 454         /* EX and TO_EX get a fresh packet, if needed */
 455         if (truncate) {
 456                 if (pih && pih->ngrec &&
 457                     AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
 458                         if (skb)
 459                                 igmpv3_sendpack(skb);
 460                         skb = igmpv3_newpack(dev, dev->mtu);
 461                 }
 462         }
 463         first = 1;
 464         psf_prev = NULL;
 465         for (psf = *psf_list; psf; psf = psf_next) {
 466                 __be32 *psrc;
 467
 468                 psf_next = psf->sf_next;
 469
 470                 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
 471                         psf_prev = psf;
 472                         continue;
 473                 }
 474
 475                 /* clear marks on query responses */
 476                 if (isquery)
 477                         psf->sf_gsresp = 0;
 478
 479                 if (AVAILABLE(skb) < sizeof(__be32) +
 480                     first*sizeof(struct igmpv3_grec)) {
 481                         if (truncate && !first)
 482                                 break;   /* truncate these */
 483                         if (pgr)
 484                                 pgr->grec_nsrcs = htons(scount);
 485                         if (skb)
 486                                 igmpv3_sendpack(skb);
 487                         skb = igmpv3_newpack(dev, dev->mtu);
 488                         first = 1;
 489                         scount = 0;
 490                 }
 491                 if (first) {
 492                         skb = add_grhead(skb, pmc, type, &pgr);
 493                         first = 0;
 494                 }
 495                 if (!skb)
 496                         return NULL;
 497                 psrc = (__be32 *)skb_put(skb, sizeof(__be32));
 498                 *psrc = psf->sf_inaddr;
 499                 scount++; stotal++;
 500                 if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
 501                      type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
 502                         psf->sf_crcount--;
 503                         if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
 504                                 if (psf_prev)
 505                                         psf_prev->sf_next = psf->sf_next;
 506                                 else
 507                                         *psf_list = psf->sf_next;
 508                                 kfree(psf);
 509                                 continue;
 510                         }
 511                 }
 512                 psf_prev = psf;
 513         }
 514
 515 empty_source:
 516         if (!stotal) {
 517                 if (type == IGMPV3_ALLOW_NEW_SOURCES ||
 518                     type == IGMPV3_BLOCK_OLD_SOURCES)
 519                         return skb;
 520                 if (pmc->crcount || isquery) {
 521                         /* make sure we have room for group header */
 522                         if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) {
 523                                 igmpv3_sendpack(skb);
 524                                 skb = NULL; /* add_grhead will get a new one */
 525                         }
 526                         skb = add_grhead(skb, pmc, type, &pgr);
 527                 }
 528         }
 529         if (pgr)
 530                 pgr->grec_nsrcs = htons(scount);
 531
 532         if (isquery)
 533                 pmc->gsquery = 0;       /* clear query state on report */
 534         return skb;
 535 }
 536
 537 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
 538 {
 539         struct sk_buff *skb = NULL;
 540         int type;
 541
 542         if (!pmc) {
 543                 rcu_read_lock();
 544                 for_each_pmc_rcu(in_dev, pmc) {
 545                         if (pmc->multiaddr == IGMP_ALL_HOSTS)
 546                                 continue;
 547                         spin_lock_bh(&pmc->lock);
 548                         if (pmc->sfcount[MCAST_EXCLUDE])
 549                                 type = IGMPV3_MODE_IS_EXCLUDE;
 550                         else
 551                                 type = IGMPV3_MODE_IS_INCLUDE;
 552                         skb = add_grec(skb, pmc, type, 0, 0);
 553                         spin_unlock_bh(&pmc->lock);
 554                 }
 555                 rcu_read_unlock();
 556         } else {
 557                 spin_lock_bh(&pmc->lock);
 558                 if (pmc->sfcount[MCAST_EXCLUDE])
 559                         type = IGMPV3_MODE_IS_EXCLUDE;
 560                 else
 561                         type = IGMPV3_MODE_IS_INCLUDE;
 562                 skb = add_grec(skb, pmc, type, 0, 0);
 563                 spin_unlock_bh(&pmc->lock);
 564         }
 565         if (!skb)
 566                 return 0;
 567         return igmpv3_sendpack(skb);
 568 }
 569
 570 /*
 571  * remove zero-count source records from a source filter list
 572  */
 573 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
 574 {
 575         struct ip_sf_list *psf_prev, *psf_next, *psf;
 576
 577         psf_prev = NULL;
 578         for (psf = *ppsf; psf; psf = psf_next) {
 579                 psf_next = psf->sf_next;
 580                 if (psf->sf_crcount == 0) {
 581                         if (psf_prev)
 582                                 psf_prev->sf_next = psf->sf_next;
 583                         else
 584                                 *ppsf = psf->sf_next;
 585                         kfree(psf);
 586                 } else
 587                         psf_prev = psf;
 588         }
 589 }
 590
 591 static void igmpv3_send_cr(struct in_device *in_dev)
 592 {
 593         struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
 594         struct sk_buff *skb = NULL;
 595         int type, dtype;
 596
 597         rcu_read_lock();
 598         spin_lock_bh(&in_dev->mc_tomb_lock);
 599
 600         /* deleted MCA's */
 601         pmc_prev = NULL;
 602         for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) {
 603                 pmc_next = pmc->next;
 604                 if (pmc->sfmode == MCAST_INCLUDE) {
 605                         type = IGMPV3_BLOCK_OLD_SOURCES;
 606                         dtype = IGMPV3_BLOCK_OLD_SOURCES;
 607                         skb = add_grec(skb, pmc, type, 1, 0);
 608                         skb = add_grec(skb, pmc, dtype, 1, 1);
 609                 }
 610                 if (pmc->crcount) {
 611                         if (pmc->sfmode == MCAST_EXCLUDE) {
 612                                 type = IGMPV3_CHANGE_TO_INCLUDE;
 613                                 skb = add_grec(skb, pmc, type, 1, 0);
 614                         }
 615                         pmc->crcount--;
 616                         if (pmc->crcount == 0) {
 617                                 igmpv3_clear_zeros(&pmc->tomb);
 618                                 igmpv3_clear_zeros(&pmc->sources);
 619                         }
 620                 }
 621                 if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
 622                         if (pmc_prev)
 623                                 pmc_prev->next = pmc_next;
 624                         else
 625                                 in_dev->mc_tomb = pmc_next;
 626                         in_dev_put(pmc->interface);
 627                         kfree(pmc);
 628                 } else
 629                         pmc_prev = pmc;
 630         }
 631         spin_unlock_bh(&in_dev->mc_tomb_lock);
 632
 633         /* change recs */
 634         for_each_pmc_rcu(in_dev, pmc) {
 635                 spin_lock_bh(&pmc->lock);
 636                 if (pmc->sfcount[MCAST_EXCLUDE]) {
 637                         type = IGMPV3_BLOCK_OLD_SOURCES;
 638                         dtype = IGMPV3_ALLOW_NEW_SOURCES;
 639                 } else {
 640                         type = IGMPV3_ALLOW_NEW_SOURCES;
 641                         dtype = IGMPV3_BLOCK_OLD_SOURCES;
 642                 }
 643                 skb = add_grec(skb, pmc, type, 0, 0);
 644                 skb = add_grec(skb, pmc, dtype, 0, 1);  /* deleted sources */
 645
 646                 /* filter mode changes */
 647                 if (pmc->crcount) {
 648                         if (pmc->sfmode == MCAST_EXCLUDE)
 649                                 type = IGMPV3_CHANGE_TO_EXCLUDE;
 650                         else
 651                                 type = IGMPV3_CHANGE_TO_INCLUDE;
 652                         skb = add_grec(skb, pmc, type, 0, 0);
 653                         pmc->crcount--;
 654                 }
 655                 spin_unlock_bh(&pmc->lock);
 656         }
 657         rcu_read_unlock();
 658
 659         if (!skb)
 660                 return;
 661         (void) igmpv3_sendpack(skb);
 662 }
 663
 664 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
 665         int type)
 666 {
 667         struct sk_buff *skb;
 668         struct iphdr *iph;
 669         struct igmphdr *ih;
 670         struct rtable *rt;
 671         struct net_device *dev = in_dev->dev;
 672         struct net *net = dev_net(dev);
 673         __be32  group = pmc ? pmc->multiaddr : 0;
 674         struct flowi4 fl4;
 675         __be32  dst;
 676         int hlen, tlen;
 677
 678         if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
 679                 return igmpv3_send_report(in_dev, pmc);
 680         else if (type == IGMP_HOST_LEAVE_MESSAGE)
 681                 dst = IGMP_ALL_ROUTER;
 682         else
 683                 dst = group;
 684
 685         rt = ip_route_output_ports(net, &fl4, NULL, dst, 0,
 686                                    0, 0,
 687                                    IPPROTO_IGMP, 0, dev->ifindex);
 688         if (IS_ERR(rt))
 689                 return -1;
 690
 691         hlen = LL_RESERVED_SPACE(dev);
 692         tlen = dev->needed_tailroom;
 693         skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC);
 694         if (skb == NULL) {
 695                 ip_rt_put(rt);
 696                 return -1;
 697         }
 698         skb->priority = TC_PRIO_CONTROL;
 699
 700         skb_dst_set(skb, &rt->dst);
 701
 702         skb_reserve(skb, hlen);
 703
 704         skb_reset_network_header(skb);
 705         iph = ip_hdr(skb);
 706         skb_put(skb, sizeof(struct iphdr) + 4);
 707
 708         iph->version  = 4;
 709         iph->ihl      = (sizeof(struct iphdr)+4)>>2;
 710         iph->tos      = 0xc0;
 711         iph->frag_off = htons(IP_DF);
 712         iph->ttl      = 1;
 713         iph->daddr    = dst;
 714         iph->saddr    = fl4.saddr;
 715         iph->protocol = IPPROTO_IGMP;
 716         ip_select_ident(skb, NULL);
 717         ((u8 *)&iph[1])[0] = IPOPT_RA;
 718         ((u8 *)&iph[1])[1] = 4;
 719         ((u8 *)&iph[1])[2] = 0;
 720         ((u8 *)&iph[1])[3] = 0;
 721
 722         ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
 723         ih->type = type;
 724         ih->code = 0;
 725         ih->csum = 0;
 726         ih->group = group;
 727         ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 728
 729         return ip_local_out(skb);
 730 }
 731
 732 static void igmp_gq_timer_expire(unsigned long data)
 733 {
 734         struct in_device *in_dev = (struct in_device *)data;
 735
 736         in_dev->mr_gq_running = 0;
 737         igmpv3_send_report(in_dev, NULL);
 738         in_dev_put(in_dev);
 739 }
 740
 741 static void igmp_ifc_timer_expire(unsigned long data)
 742 {
 743         struct in_device *in_dev = (struct in_device *)data;
 744
 745         igmpv3_send_cr(in_dev);
 746         if (in_dev->mr_ifc_count) {
 747                 in_dev->mr_ifc_count--;
 748                 igmp_ifc_start_timer(in_dev,
 749                                      unsolicited_report_interval(in_dev));
 750         }
 751         in_dev_put(in_dev);
 752 }
 753
 754 static void igmp_ifc_event(struct in_device *in_dev)
 755 {
 756         if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 757                 return;
 758         in_dev->mr_ifc_count = in_dev->mr_qrv ?: sysctl_igmp_qrv;
 759         igmp_ifc_start_timer(in_dev, 1);
 760 }
 761
 762
 763 static void igmp_timer_expire(unsigned long data)
 764 {
 765         struct ip_mc_list *im = (struct ip_mc_list *)data;
 766         struct in_device *in_dev = im->interface;
 767
 768         spin_lock(&im->lock);
 769         im->tm_running = 0;
 770
 771         if (im->unsolicit_count) {
 772                 im->unsolicit_count--;
 773                 igmp_start_timer(im, unsolicited_report_interval(in_dev));
 774         }
 775         im->reporter = 1;
 776         spin_unlock(&im->lock);
 777
 778         if (IGMP_V1_SEEN(in_dev))
 779                 igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
 780         else if (IGMP_V2_SEEN(in_dev))
 781                 igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
 782         else
 783                 igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
 784
 785         ip_ma_put(im);
 786 }
 787
 788 /* mark EXCLUDE-mode sources */
 789 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 790 {
 791         struct ip_sf_list *psf;
 792         int i, scount;
 793
 794         scount = 0;
 795         for (psf = pmc->sources; psf; psf = psf->sf_next) {
 796                 if (scount == nsrcs)
 797                         break;
 798                 for (i = 0; i < nsrcs; i++) {
 799                         /* skip inactive filters */
 800                         if (psf->sf_count[MCAST_INCLUDE] ||
 801                             pmc->sfcount[MCAST_EXCLUDE] !=
 802                             psf->sf_count[MCAST_EXCLUDE])
 803                                 break;
 804                         if (srcs[i] == psf->sf_inaddr) {
 805                                 scount++;
 806                                 break;
 807                         }
 808                 }
 809         }
 810         pmc->gsquery = 0;
 811         if (scount == nsrcs)    /* all sources excluded */
 812                 return 0;
 813         return 1;
 814 }
 815
 816 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 817 {
 818         struct ip_sf_list *psf;
 819         int i, scount;
 820
 821         if (pmc->sfmode == MCAST_EXCLUDE)
 822                 return igmp_xmarksources(pmc, nsrcs, srcs);
 823
 824         /* mark INCLUDE-mode sources */
 825         scount = 0;
 826         for (psf = pmc->sources; psf; psf = psf->sf_next) {
 827                 if (scount == nsrcs)
 828                         break;
 829                 for (i = 0; i < nsrcs; i++)
 830                         if (srcs[i] == psf->sf_inaddr) {
 831                                 psf->sf_gsresp = 1;
 832                                 scount++;
 833                                 break;
 834                         }
 835         }
 836         if (!scount) {
 837                 pmc->gsquery = 0;
 838                 return 0;
 839         }
 840         pmc->gsquery = 1;
 841         return 1;
 842 }
 843
 844 /* return true if packet was dropped */
 845 static bool igmp_heard_report(struct in_device *in_dev, __be32 group)
 846 {
 847         struct ip_mc_list *im;
 848
 849         /* Timers are only set for non-local groups */
 850
 851         if (group == IGMP_ALL_HOSTS)
 852                 return false;
 853
 854         rcu_read_lock();
 855         for_each_pmc_rcu(in_dev, im) {
 856                 if (im->multiaddr == group) {
 857                         igmp_stop_timer(im);
 858                         break;
 859                 }
 860         }
 861         rcu_read_unlock();
 862         return false;
 863 }
 864
 865 /* return true if packet was dropped */
 866 static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
 867         int len)
 868 {
 869         struct igmphdr          *ih = igmp_hdr(skb);
 870         struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
 871         struct ip_mc_list       *im;
 872         __be32                  group = ih->group;
 873         int                     max_delay;
 874         int                     mark = 0;
 875
 876
 877         if (len == 8) {
 878                 if (ih->code == 0) {
 879                         /* Alas, old v1 router presents here. */
 880
 881                         max_delay = IGMP_Query_Response_Interval;
 882                         in_dev->mr_v1_seen = jiffies +
 883                                 IGMP_V1_Router_Present_Timeout;
 884                         group = 0;
 885                 } else {
 886                         /* v2 router present */
 887                         max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
 888                         in_dev->mr_v2_seen = jiffies +
 889                                 IGMP_V2_Router_Present_Timeout;
 890                 }
 891                 /* cancel the interface change timer */
 892                 in_dev->mr_ifc_count = 0;
 893                 if (del_timer(&in_dev->mr_ifc_timer))
 894                         __in_dev_put(in_dev);
 895                 /* clear deleted report items */
 896                 igmpv3_clear_delrec(in_dev);
 897         } else if (len < 12) {
 898                 return true;    /* ignore bogus packet; freed by caller */
 899         } else if (IGMP_V1_SEEN(in_dev)) {
 900                 /* This is a v3 query with v1 queriers present */
 901                 max_delay = IGMP_Query_Response_Interval;
 902                 group = 0;
 903         } else if (IGMP_V2_SEEN(in_dev)) {
 904                 /* this is a v3 query with v2 queriers present;
 905                  * Interpretation of the max_delay code is problematic here.
 906                  * A real v2 host would use ih_code directly, while v3 has a
 907                  * different encoding. We use the v3 encoding as more likely
 908                  * to be intended in a v3 query.
 909                  */
 910                 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 911                 if (!max_delay)
 912                         max_delay = 1;  /* can't mod w/ 0 */
 913         } else { /* v3 */
 914                 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
 915                         return true;
 916
 917                 ih3 = igmpv3_query_hdr(skb);
 918                 if (ih3->nsrcs) {
 919                         if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
 920                                            + ntohs(ih3->nsrcs)*sizeof(__be32)))
 921                                 return true;
 922                         ih3 = igmpv3_query_hdr(skb);
 923                 }
 924
 925                 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 926                 if (!max_delay)
 927                         max_delay = 1;  /* can't mod w/ 0 */
 928                 in_dev->mr_maxdelay = max_delay;
 929                 if (ih3->qrv)
 930                         in_dev->mr_qrv = ih3->qrv;
 931                 if (!group) { /* general query */
 932                         if (ih3->nsrcs)
 933                                 return true;    /* no sources allowed */
 934                         igmp_gq_start_timer(in_dev);
 935                         return false;
 936                 }
 937                 /* mark sources to include, if group & source-specific */
 938                 mark = ih3->nsrcs != 0;
 939         }
 940
 941         /*
 942          * - Start the timers in all of our membership records
 943          *   that the query applies to for the interface on
 944          *   which the query arrived excl. those that belong
 945          *   to a "local" group (224.0.0.X)
 946          * - For timers already running check if they need to
 947          *   be reset.
 948          * - Use the igmp->igmp_code field as the maximum
 949          *   delay possible
 950          */
 951         rcu_read_lock();
 952         for_each_pmc_rcu(in_dev, im) {
 953                 int changed;
 954
 955                 if (group && group != im->multiaddr)
 956                         continue;
 957                 if (im->multiaddr == IGMP_ALL_HOSTS)
 958                         continue;
 959                 spin_lock_bh(&im->lock);
 960                 if (im->tm_running)
 961                         im->gsquery = im->gsquery && mark;
 962                 else
 963                         im->gsquery = mark;
 964                 changed = !im->gsquery ||
 965                         igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
 966                 spin_unlock_bh(&im->lock);
 967                 if (changed)
 968                         igmp_mod_timer(im, max_delay);
 969         }
 970         rcu_read_unlock();
 971         return false;
 972 }
 973
 974 /* called in rcu_read_lock() section */
 975 int igmp_rcv(struct sk_buff *skb)
 976 {
 977         /* This basically follows the spec line by line -- see RFC1112 */
 978         struct igmphdr *ih;
 979         struct in_device *in_dev = __in_dev_get_rcu(skb->dev);
 980         int len = skb->len;
 981         bool dropped = true;
 982
 983         if (in_dev == NULL)
 984                 goto drop;
 985
 986         if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
 987                 goto drop;
 988
 989         if (skb_checksum_simple_validate(skb))
 990                 goto drop;
 991
 992         ih = igmp_hdr(skb);
 993         switch (ih->type) {
 994         case IGMP_HOST_MEMBERSHIP_QUERY:
 995                 dropped = igmp_heard_query(in_dev, skb, len);
 996                 break;
 997         case IGMP_HOST_MEMBERSHIP_REPORT:
 998         case IGMPV2_HOST_MEMBERSHIP_REPORT:
 999                 /* Is it our report looped back? */
1000                 if (rt_is_output_route(skb_rtable(skb)))
1001                         break;
1002                 /* don't rely on MC router hearing unicast reports */
1003                 if (skb->pkt_type == PACKET_MULTICAST ||
1004                     skb->pkt_type == PACKET_BROADCAST)
1005                         dropped = igmp_heard_report(in_dev, ih->group);
1006                 break;
1007         case IGMP_PIM:
1008 #ifdef CONFIG_IP_PIMSM_V1
1009                 return pim_rcv_v1(skb);
1010 #endif
1011         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1012         case IGMP_DVMRP:
1013         case IGMP_TRACE:
1014         case IGMP_HOST_LEAVE_MESSAGE:
1015         case IGMP_MTRACE:
1016         case IGMP_MTRACE_RESP:
1017                 break;
1018         default:
1019                 break;
1020         }
1021
1022 drop:
1023         if (dropped)
1024                 kfree_skb(skb);
1025         else
1026                 consume_skb(skb);
1027         return 0;
1028 }
1029
1030 #endif
1031
1032
1033 /*
1034  *      Add a filter to a device
1035  */
1036
1037 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1038 {
1039         char buf[MAX_ADDR_LEN];
1040         struct net_device *dev = in_dev->dev;
1041
1042         /* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1043            We will get multicast token leakage, when IFF_MULTICAST
1044            is changed. This check should be done in ndo_set_rx_mode
1045            routine. Something sort of:
1046            if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1047            --ANK
1048            */
1049         if (arp_mc_map(addr, buf, dev, 0) == 0)
1050                 dev_mc_add(dev, buf);
1051 }
1052
1053 /*
1054  *      Remove a filter from a device
1055  */
1056
1057 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1058 {
1059         char buf[MAX_ADDR_LEN];
1060         struct net_device *dev = in_dev->dev;
1061
1062         if (arp_mc_map(addr, buf, dev, 0) == 0)
1063                 dev_mc_del(dev, buf);
1064 }
1065
1066 #ifdef CONFIG_IP_MULTICAST
1067 /*
1068  * deleted ip_mc_list manipulation
1069  */
1070 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1071 {
1072         struct ip_mc_list *pmc;
1073
1074         /* this is an "ip_mc_list" for convenience; only the fields below
1075          * are actually used. In particular, the refcnt and users are not
1076          * used for management of the delete list. Using the same structure
1077          * for deleted items allows change reports to use common code with
1078          * non-deleted or query-response MCA's.
1079          */
1080         pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
1081         if (!pmc)
1082                 return;
1083         spin_lock_bh(&im->lock);
1084         pmc->interface = im->interface;
1085         in_dev_hold(in_dev);
1086         pmc->multiaddr = im->multiaddr;
1087         pmc->crcount = in_dev->mr_qrv ?: sysctl_igmp_qrv;
1088         pmc->sfmode = im->sfmode;
1089         if (pmc->sfmode == MCAST_INCLUDE) {
1090                 struct ip_sf_list *psf;
1091
1092                 pmc->tomb = im->tomb;
1093                 pmc->sources = im->sources;
1094                 im->tomb = im->sources = NULL;
1095                 for (psf = pmc->sources; psf; psf = psf->sf_next)
1096                         psf->sf_crcount = pmc->crcount;
1097         }
1098         spin_unlock_bh(&im->lock);
1099
1100         spin_lock_bh(&in_dev->mc_tomb_lock);
1101         pmc->next = in_dev->mc_tomb;
1102         in_dev->mc_tomb = pmc;
1103         spin_unlock_bh(&in_dev->mc_tomb_lock);
1104 }
1105
1106 static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr)
1107 {
1108         struct ip_mc_list *pmc, *pmc_prev;
1109         struct ip_sf_list *psf, *psf_next;
1110
1111         spin_lock_bh(&in_dev->mc_tomb_lock);
1112         pmc_prev = NULL;
1113         for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) {
1114                 if (pmc->multiaddr == multiaddr)
1115                         break;
1116                 pmc_prev = pmc;
1117         }
1118         if (pmc) {
1119                 if (pmc_prev)
1120                         pmc_prev->next = pmc->next;
1121                 else
1122                         in_dev->mc_tomb = pmc->next;
1123         }
1124         spin_unlock_bh(&in_dev->mc_tomb_lock);
1125         if (pmc) {
1126                 for (psf = pmc->tomb; psf; psf = psf_next) {
1127                         psf_next = psf->sf_next;
1128                         kfree(psf);
1129                 }
1130                 in_dev_put(pmc->interface);
1131                 kfree(pmc);
1132         }
1133 }
1134
1135 static void igmpv3_clear_delrec(struct in_device *in_dev)
1136 {
1137         struct ip_mc_list *pmc, *nextpmc;
1138
1139         spin_lock_bh(&in_dev->mc_tomb_lock);
1140         pmc = in_dev->mc_tomb;
1141         in_dev->mc_tomb = NULL;
1142         spin_unlock_bh(&in_dev->mc_tomb_lock);
1143
1144         for (; pmc; pmc = nextpmc) {
1145                 nextpmc = pmc->next;
1146                 ip_mc_clear_src(pmc);
1147                 in_dev_put(pmc->interface);
1148                 kfree(pmc);
1149         }
1150         /* clear dead sources, too */
1151         rcu_read_lock();
1152         for_each_pmc_rcu(in_dev, pmc) {
1153                 struct ip_sf_list *psf, *psf_next;
1154
1155                 spin_lock_bh(&pmc->lock);
1156                 psf = pmc->tomb;
1157                 pmc->tomb = NULL;
1158                 spin_unlock_bh(&pmc->lock);
1159                 for (; psf; psf = psf_next) {
1160                         psf_next = psf->sf_next;
1161                         kfree(psf);
1162                 }
1163         }
1164         rcu_read_unlock();
1165 }
1166 #endif
1167
1168 static void igmp_group_dropped(struct ip_mc_list *im)
1169 {
1170         struct in_device *in_dev = im->interface;
1171 #ifdef CONFIG_IP_MULTICAST
1172         int reporter;
1173 #endif
1174
1175         if (im->loaded) {
1176                 im->loaded = 0;
1177                 ip_mc_filter_del(in_dev, im->multiaddr);
1178         }
1179
1180 #ifdef CONFIG_IP_MULTICAST
1181         if (im->multiaddr == IGMP_ALL_HOSTS)
1182                 return;
1183
1184         reporter = im->reporter;
1185         igmp_stop_timer(im);
1186
1187         if (!in_dev->dead) {
1188                 if (IGMP_V1_SEEN(in_dev))
1189                         return;
1190                 if (IGMP_V2_SEEN(in_dev)) {
1191                         if (reporter)
1192                                 igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1193                         return;
1194                 }
1195                 /* IGMPv3 */
1196                 igmpv3_add_delrec(in_dev, im);
1197
1198                 igmp_ifc_event(in_dev);
1199         }
1200 #endif
1201 }
1202
1203 static void igmp_group_added(struct ip_mc_list *im)
1204 {
1205         struct in_device *in_dev = im->interface;
1206
1207         if (im->loaded == 0) {
1208                 im->loaded = 1;
1209                 ip_mc_filter_add(in_dev, im->multiaddr);
1210         }
1211
1212 #ifdef CONFIG_IP_MULTICAST
1213         if (im->multiaddr == IGMP_ALL_HOSTS)
1214                 return;
1215
1216         if (in_dev->dead)
1217                 return;
1218         if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1219                 spin_lock_bh(&im->lock);
1220                 igmp_start_timer(im, IGMP_Initial_Report_Delay);
1221                 spin_unlock_bh(&im->lock);
1222                 return;
1223         }
1224         /* else, v3 */
1225
1226         im->crcount = in_dev->mr_qrv ?: sysctl_igmp_qrv;
1227         igmp_ifc_event(in_dev);
1228 #endif
1229 }
1230
1231
1232 /*
1233  *      Multicast list managers
1234  */
1235
1236 static u32 ip_mc_hash(const struct ip_mc_list *im)
1237 {
1238         return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
1239 }
1240
1241 static void ip_mc_hash_add(struct in_device *in_dev,
1242                            struct ip_mc_list *im)
1243 {
1244         struct ip_mc_list __rcu **mc_hash;
1245         u32 hash;
1246
1247         mc_hash = rtnl_dereference(in_dev->mc_hash);
1248         if (mc_hash) {
1249                 hash = ip_mc_hash(im);
1250                 im->next_hash = mc_hash[hash];
1251                 rcu_assign_pointer(mc_hash[hash], im);
1252                 return;
1253         }
1254
1255         /* do not use a hash table for small number of items */
1256         if (in_dev->mc_count < 4)
1257                 return;
1258
1259         mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
1260                           GFP_KERNEL);
1261         if (!mc_hash)
1262                 return;
1263
1264         for_each_pmc_rtnl(in_dev, im) {
1265                 hash = ip_mc_hash(im);
1266                 im->next_hash = mc_hash[hash];
1267                 RCU_INIT_POINTER(mc_hash[hash], im);
1268         }
1269
1270         rcu_assign_pointer(in_dev->mc_hash, mc_hash);
1271 }
1272
1273 static void ip_mc_hash_remove(struct in_device *in_dev,
1274                               struct ip_mc_list *im)
1275 {
1276         struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
1277         struct ip_mc_list *aux;
1278
1279         if (!mc_hash)
1280                 return;
1281         mc_hash += ip_mc_hash(im);
1282         while ((aux = rtnl_dereference(*mc_hash)) != im)
1283                 mc_hash = &aux->next_hash;
1284         *mc_hash = im->next_hash;
1285 }
1286
1287
1288 /*
1289  *      A socket has joined a multicast group on device dev.
1290  */
1291
1292 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1293 {
1294         struct ip_mc_list *im;
1295
1296         ASSERT_RTNL();
1297
1298         for_each_pmc_rtnl(in_dev, im) {
1299                 if (im->multiaddr == addr) {
1300                         im->users++;
1301                         ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1302                         goto out;
1303                 }
1304         }
1305
1306         im = kzalloc(sizeof(*im), GFP_KERNEL);
1307         if (!im)
1308                 goto out;
1309
1310         im->users = 1;
1311         im->interface = in_dev;
1312         in_dev_hold(in_dev);
1313         im->multiaddr = addr;
1314         /* initial mode is (EX, empty) */
1315         im->sfmode = MCAST_EXCLUDE;
1316         im->sfcount[MCAST_EXCLUDE] = 1;
1317         atomic_set(&im->refcnt, 1);
1318         spin_lock_init(&im->lock);
1319 #ifdef CONFIG_IP_MULTICAST
1320         setup_timer(&im->timer, igmp_timer_expire, (unsigned long)im);
1321         im->unsolicit_count = sysctl_igmp_qrv;
1322 #endif
1323
1324         im->next_rcu = in_dev->mc_list;
1325         in_dev->mc_count++;
1326         rcu_assign_pointer(in_dev->mc_list, im);
1327
1328         ip_mc_hash_add(in_dev, im);
1329
1330 #ifdef CONFIG_IP_MULTICAST
1331         igmpv3_del_delrec(in_dev, im->multiaddr);
1332 #endif
1333         igmp_group_added(im);
1334         if (!in_dev->dead)
1335                 ip_rt_multicast_event(in_dev);
1336 out:
1337         return;
1338 }
1339 EXPORT_SYMBOL(ip_mc_inc_group);
1340
1341 /*
1342  *      Resend IGMP JOIN report; used by netdev notifier.
1343  */
1344 static void ip_mc_rejoin_groups(struct in_device *in_dev)
1345 {
1346 #ifdef CONFIG_IP_MULTICAST
1347         struct ip_mc_list *im;
1348         int type;
1349
1350         ASSERT_RTNL();
1351
1352         for_each_pmc_rtnl(in_dev, im) {
1353                 if (im->multiaddr == IGMP_ALL_HOSTS)
1354                         continue;
1355
1356                 /* a failover is happening and switches
1357                  * must be notified immediately
1358                  */
1359                 if (IGMP_V1_SEEN(in_dev))
1360                         type = IGMP_HOST_MEMBERSHIP_REPORT;
1361                 else if (IGMP_V2_SEEN(in_dev))
1362                         type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1363                 else
1364                         type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1365                 igmp_send_report(in_dev, im, type);
1366         }
1367 #endif
1368 }
1369
1370 /*
1371  *      A socket has left a multicast group on device dev
1372  */
1373
1374 void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
1375 {
1376         struct ip_mc_list *i;
1377         struct ip_mc_list __rcu **ip;
1378
1379         ASSERT_RTNL();
1380
1381         for (ip = &in_dev->mc_list;
1382              (i = rtnl_dereference(*ip)) != NULL;
1383              ip = &i->next_rcu) {
1384                 if (i->multiaddr == addr) {
1385                         if (--i->users == 0) {
1386                                 ip_mc_hash_remove(in_dev, i);
1387                                 *ip = i->next_rcu;
1388                                 in_dev->mc_count--;
1389                                 igmp_group_dropped(i);
1390                                 ip_mc_clear_src(i);
1391
1392                                 if (!in_dev->dead)
1393                                         ip_rt_multicast_event(in_dev);
1394
1395                                 ip_ma_put(i);
1396                                 return;
1397                         }
1398                         break;
1399                 }
1400         }
1401 }
1402 EXPORT_SYMBOL(ip_mc_dec_group);
1403
1404 /* Device changing type */
1405
1406 void ip_mc_unmap(struct in_device *in_dev)
1407 {
1408         struct ip_mc_list *pmc;
1409
1410         ASSERT_RTNL();
1411
1412         for_each_pmc_rtnl(in_dev, pmc)
1413                 igmp_group_dropped(pmc);
1414 }
1415
1416 void ip_mc_remap(struct in_device *in_dev)
1417 {
1418         struct ip_mc_list *pmc;
1419
1420         ASSERT_RTNL();
1421
1422         for_each_pmc_rtnl(in_dev, pmc)
1423                 igmp_group_added(pmc);
1424 }
1425
1426 /* Device going down */
1427
1428 void ip_mc_down(struct in_device *in_dev)
1429 {
1430         struct ip_mc_list *pmc;
1431
1432         ASSERT_RTNL();
1433
1434         for_each_pmc_rtnl(in_dev, pmc)
1435                 igmp_group_dropped(pmc);
1436
1437 #ifdef CONFIG_IP_MULTICAST
1438         in_dev->mr_ifc_count = 0;
1439         if (del_timer(&in_dev->mr_ifc_timer))
1440                 __in_dev_put(in_dev);
1441         in_dev->mr_gq_running = 0;
1442         if (del_timer(&in_dev->mr_gq_timer))
1443                 __in_dev_put(in_dev);
1444         igmpv3_clear_delrec(in_dev);
1445 #endif
1446
1447         ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1448 }
1449
1450 void ip_mc_init_dev(struct in_device *in_dev)
1451 {
1452         ASSERT_RTNL();
1453
1454 #ifdef CONFIG_IP_MULTICAST
1455         setup_timer(&in_dev->mr_gq_timer, igmp_gq_timer_expire,
1456                         (unsigned long)in_dev);
1457         setup_timer(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire,
1458                         (unsigned long)in_dev);
1459         in_dev->mr_qrv = sysctl_igmp_qrv;
1460 #endif
1461
1462         spin_lock_init(&in_dev->mc_tomb_lock);
1463 }
1464
1465 /* Device going up */
1466
1467 void ip_mc_up(struct in_device *in_dev)
1468 {
1469         struct ip_mc_list *pmc;
1470
1471         ASSERT_RTNL();
1472
1473 #ifdef CONFIG_IP_MULTICAST
1474         in_dev->mr_qrv = sysctl_igmp_qrv;
1475 #endif
1476         ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1477
1478         for_each_pmc_rtnl(in_dev, pmc)
1479                 igmp_group_added(pmc);
1480 }
1481
1482 /*
1483  *      Device is about to be destroyed: clean up.
1484  */
1485
1486 void ip_mc_destroy_dev(struct in_device *in_dev)
1487 {
1488         struct ip_mc_list *i;
1489
1490         ASSERT_RTNL();
1491
1492         /* Deactivate timers */
1493         ip_mc_down(in_dev);
1494
1495         while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1496                 in_dev->mc_list = i->next_rcu;
1497                 in_dev->mc_count--;
1498
1499                 /* We've dropped the groups in ip_mc_down already */
1500                 ip_mc_clear_src(i);
1501                 ip_ma_put(i);
1502         }
1503 }
1504
1505 /* RTNL is locked */
1506 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1507 {
1508         struct net_device *dev = NULL;
1509         struct in_device *idev = NULL;
1510
1511         if (imr->imr_ifindex) {
1512                 idev = inetdev_by_index(net, imr->imr_ifindex);
1513                 return idev;
1514         }
1515         if (imr->imr_address.s_addr) {
1516                 dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1517                 if (!dev)
1518                         return NULL;
1519         }
1520
1521         if (!dev) {
1522                 struct rtable *rt = ip_route_output(net,
1523                                                     imr->imr_multiaddr.s_addr,
1524                                                     0, 0, 0);
1525                 if (!IS_ERR(rt)) {
1526                         dev = rt->dst.dev;
1527                         ip_rt_put(rt);
1528                 }
1529         }
1530         if (dev) {
1531                 imr->imr_ifindex = dev->ifindex;
1532                 idev = __in_dev_get_rtnl(dev);
1533         }
1534         return idev;
1535 }
1536
1537 /*
1538  *      Join a socket to a group
1539  */
1540 int sysctl_igmp_max_memberships __read_mostly = IP_MAX_MEMBERSHIPS;
1541 int sysctl_igmp_max_msf __read_mostly = IP_MAX_MSF;
1542 #ifdef CONFIG_IP_MULTICAST
1543 int sysctl_igmp_qrv __read_mostly = IGMP_Query_Robustness_Variable;
1544 #endif
1545
1546 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1547         __be32 *psfsrc)
1548 {
1549         struct ip_sf_list *psf, *psf_prev;
1550         int rv = 0;
1551
1552         psf_prev = NULL;
1553         for (psf = pmc->sources; psf; psf = psf->sf_next) {
1554                 if (psf->sf_inaddr == *psfsrc)
1555                         break;
1556                 psf_prev = psf;
1557         }
1558         if (!psf || psf->sf_count[sfmode] == 0) {
1559                 /* source filter not found, or count wrong =>  bug */
1560                 return -ESRCH;
1561         }
1562         psf->sf_count[sfmode]--;
1563         if (psf->sf_count[sfmode] == 0) {
1564                 ip_rt_multicast_event(pmc->interface);
1565         }
1566         if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1567 #ifdef CONFIG_IP_MULTICAST
1568                 struct in_device *in_dev = pmc->interface;
1569 #endif
1570
1571                 /* no more filters for this source */
1572                 if (psf_prev)
1573                         psf_prev->sf_next = psf->sf_next;
1574                 else
1575                         pmc->sources = psf->sf_next;
1576 #ifdef CONFIG_IP_MULTICAST
1577                 if (psf->sf_oldin &&
1578                     !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1579                         psf->sf_crcount = in_dev->mr_qrv ?: sysctl_igmp_qrv;
1580                         psf->sf_next = pmc->tomb;
1581                         pmc->tomb = psf;
1582                         rv = 1;
1583                 } else
1584 #endif
1585                         kfree(psf);
1586         }
1587         return rv;
1588 }
1589
1590 #ifndef CONFIG_IP_MULTICAST
1591 #define igmp_ifc_event(x)       do { } while (0)
1592 #endif
1593
1594 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1595                          int sfcount, __be32 *psfsrc, int delta)
1596 {
1597         struct ip_mc_list *pmc;
1598         int     changerec = 0;
1599         int     i, err;
1600
1601         if (!in_dev)
1602                 return -ENODEV;
1603         rcu_read_lock();
1604         for_each_pmc_rcu(in_dev, pmc) {
1605                 if (*pmca == pmc->multiaddr)
1606                         break;
1607         }
1608         if (!pmc) {
1609                 /* MCA not found?? bug */
1610                 rcu_read_unlock();
1611                 return -ESRCH;
1612         }
1613         spin_lock_bh(&pmc->lock);
1614         rcu_read_unlock();
1615 #ifdef CONFIG_IP_MULTICAST
1616         sf_markstate(pmc);
1617 #endif
1618         if (!delta) {
1619                 err = -EINVAL;
1620                 if (!pmc->sfcount[sfmode])
1621                         goto out_unlock;
1622                 pmc->sfcount[sfmode]--;
1623         }
1624         err = 0;
1625         for (i = 0; i < sfcount; i++) {
1626                 int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1627
1628                 changerec |= rv > 0;
1629                 if (!err && rv < 0)
1630                         err = rv;
1631         }
1632         if (pmc->sfmode == MCAST_EXCLUDE &&
1633             pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1634             pmc->sfcount[MCAST_INCLUDE]) {
1635 #ifdef CONFIG_IP_MULTICAST
1636                 struct ip_sf_list *psf;
1637 #endif
1638
1639                 /* filter mode change */
1640                 pmc->sfmode = MCAST_INCLUDE;
1641 #ifdef CONFIG_IP_MULTICAST
1642                 pmc->crcount = in_dev->mr_qrv ?: sysctl_igmp_qrv;
1643                 in_dev->mr_ifc_count = pmc->crcount;
1644                 for (psf = pmc->sources; psf; psf = psf->sf_next)
1645                         psf->sf_crcount = 0;
1646                 igmp_ifc_event(pmc->interface);
1647         } else if (sf_setstate(pmc) || changerec) {
1648                 igmp_ifc_event(pmc->interface);
1649 #endif
1650         }
1651 out_unlock:
1652         spin_unlock_bh(&pmc->lock);
1653         return err;
1654 }
1655
1656 /*
1657  * Add multicast single-source filter to the interface list
1658  */
1659 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1660         __be32 *psfsrc)
1661 {
1662         struct ip_sf_list *psf, *psf_prev;
1663
1664         psf_prev = NULL;
1665         for (psf = pmc->sources; psf; psf = psf->sf_next) {
1666                 if (psf->sf_inaddr == *psfsrc)
1667                         break;
1668                 psf_prev = psf;
1669         }
1670         if (!psf) {
1671                 psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1672                 if (!psf)
1673                         return -ENOBUFS;
1674                 psf->sf_inaddr = *psfsrc;
1675                 if (psf_prev) {
1676                         psf_prev->sf_next = psf;
1677                 } else
1678                         pmc->sources = psf;
1679         }
1680         psf->sf_count[sfmode]++;
1681         if (psf->sf_count[sfmode] == 1) {
1682                 ip_rt_multicast_event(pmc->interface);
1683         }
1684         return 0;
1685 }
1686
1687 #ifdef CONFIG_IP_MULTICAST
1688 static void sf_markstate(struct ip_mc_list *pmc)
1689 {
1690         struct ip_sf_list *psf;
1691         int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1692
1693         for (psf = pmc->sources; psf; psf = psf->sf_next)
1694                 if (pmc->sfcount[MCAST_EXCLUDE]) {
1695                         psf->sf_oldin = mca_xcount ==
1696                                 psf->sf_count[MCAST_EXCLUDE] &&
1697                                 !psf->sf_count[MCAST_INCLUDE];
1698                 } else
1699                         psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1700 }
1701
1702 static int sf_setstate(struct ip_mc_list *pmc)
1703 {
1704         struct ip_sf_list *psf, *dpsf;
1705         int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1706         int qrv = pmc->interface->mr_qrv;
1707         int new_in, rv;
1708
1709         rv = 0;
1710         for (psf = pmc->sources; psf; psf = psf->sf_next) {
1711                 if (pmc->sfcount[MCAST_EXCLUDE]) {
1712                         new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1713                                 !psf->sf_count[MCAST_INCLUDE];
1714                 } else
1715                         new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1716                 if (new_in) {
1717                         if (!psf->sf_oldin) {
1718                                 struct ip_sf_list *prev = NULL;
1719
1720                                 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) {
1721                                         if (dpsf->sf_inaddr == psf->sf_inaddr)
1722                                                 break;
1723                                         prev = dpsf;
1724                                 }
1725                                 if (dpsf) {
1726                                         if (prev)
1727                                                 prev->sf_next = dpsf->sf_next;
1728                                         else
1729                                                 pmc->tomb = dpsf->sf_next;
1730                                         kfree(dpsf);
1731                                 }
1732                                 psf->sf_crcount = qrv;
1733                                 rv++;
1734                         }
1735                 } else if (psf->sf_oldin) {
1736
1737                         psf->sf_crcount = 0;
1738                         /*
1739                          * add or update "delete" records if an active filter
1740                          * is now inactive
1741                          */
1742                         for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next)
1743                                 if (dpsf->sf_inaddr == psf->sf_inaddr)
1744                                         break;
1745                         if (!dpsf) {
1746                                 dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
1747                                 if (!dpsf)
1748                                         continue;
1749                                 *dpsf = *psf;
1750                                 /* pmc->lock held by callers */
1751                                 dpsf->sf_next = pmc->tomb;
1752                                 pmc->tomb = dpsf;
1753                         }
1754                         dpsf->sf_crcount = qrv;
1755                         rv++;
1756                 }
1757         }
1758         return rv;
1759 }
1760 #endif
1761
1762 /*
1763  * Add multicast source filter list to the interface list
1764  */
1765 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1766                          int sfcount, __be32 *psfsrc, int delta)
1767 {
1768         struct ip_mc_list *pmc;
1769         int     isexclude;
1770         int     i, err;
1771
1772         if (!in_dev)
1773                 return -ENODEV;
1774         rcu_read_lock();
1775         for_each_pmc_rcu(in_dev, pmc) {
1776                 if (*pmca == pmc->multiaddr)
1777                         break;
1778         }
1779         if (!pmc) {
1780                 /* MCA not found?? bug */
1781                 rcu_read_unlock();
1782                 return -ESRCH;
1783         }
1784         spin_lock_bh(&pmc->lock);
1785         rcu_read_unlock();
1786
1787 #ifdef CONFIG_IP_MULTICAST
1788         sf_markstate(pmc);
1789 #endif
1790         isexclude = pmc->sfmode == MCAST_EXCLUDE;
1791         if (!delta)
1792                 pmc->sfcount[sfmode]++;
1793         err = 0;
1794         for (i = 0; i < sfcount; i++) {
1795                 err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]);
1796                 if (err)
1797                         break;
1798         }
1799         if (err) {
1800                 int j;
1801
1802                 if (!delta)
1803                         pmc->sfcount[sfmode]--;
1804                 for (j = 0; j < i; j++)
1805                         (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
1806         } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
1807 #ifdef CONFIG_IP_MULTICAST
1808                 struct ip_sf_list *psf;
1809                 in_dev = pmc->interface;
1810 #endif
1811
1812                 /* filter mode change */
1813                 if (pmc->sfcount[MCAST_EXCLUDE])
1814                         pmc->sfmode = MCAST_EXCLUDE;
1815                 else if (pmc->sfcount[MCAST_INCLUDE])
1816                         pmc->sfmode = MCAST_INCLUDE;
1817 #ifdef CONFIG_IP_MULTICAST
1818                 /* else no filters; keep old mode for reports */
1819
1820                 pmc->crcount = in_dev->mr_qrv ?: sysctl_igmp_qrv;
1821                 in_dev->mr_ifc_count = pmc->crcount;
1822                 for (psf = pmc->sources; psf; psf = psf->sf_next)
1823                         psf->sf_crcount = 0;
1824                 igmp_ifc_event(in_dev);
1825         } else if (sf_setstate(pmc)) {
1826                 igmp_ifc_event(in_dev);
1827 #endif
1828         }
1829         spin_unlock_bh(&pmc->lock);
1830         return err;
1831 }
1832
1833 static void ip_mc_clear_src(struct ip_mc_list *pmc)
1834 {
1835         struct ip_sf_list *psf, *nextpsf;
1836
1837         for (psf = pmc->tomb; psf; psf = nextpsf) {
1838                 nextpsf = psf->sf_next;
1839                 kfree(psf);
1840         }
1841         pmc->tomb = NULL;
1842         for (psf = pmc->sources; psf; psf = nextpsf) {
1843                 nextpsf = psf->sf_next;
1844                 kfree(psf);
1845         }
1846         pmc->sources = NULL;
1847         pmc->sfmode = MCAST_EXCLUDE;
1848         pmc->sfcount[MCAST_INCLUDE] = 0;
1849         pmc->sfcount[MCAST_EXCLUDE] = 1;
1850 }
1851
1852
1853 /*
1854  * Join a multicast group
1855  */
1856 int ip_mc_join_group(struct sock *sk , struct ip_mreqn *imr)
1857 {
1858         int err;
1859         __be32 addr = imr->imr_multiaddr.s_addr;
1860         struct ip_mc_socklist *iml = NULL, *i;
1861         struct in_device *in_dev;
1862         struct inet_sock *inet = inet_sk(sk);
1863         struct net *net = sock_net(sk);
1864         int ifindex;
1865         int count = 0;
1866
1867         if (!ipv4_is_multicast(addr))
1868                 return -EINVAL;
1869
1870         rtnl_lock();
1871
1872         in_dev = ip_mc_find_dev(net, imr);
1873
1874         if (!in_dev) {
1875                 iml = NULL;
1876                 err = -ENODEV;
1877                 goto done;
1878         }
1879
1880         err = -EADDRINUSE;
1881         ifindex = imr->imr_ifindex;
1882         for_each_pmc_rtnl(inet, i) {
1883                 if (i->multi.imr_multiaddr.s_addr == addr &&
1884                     i->multi.imr_ifindex == ifindex)
1885                         goto done;
1886                 count++;
1887         }
1888         err = -ENOBUFS;
1889         if (count >= sysctl_igmp_max_memberships)
1890                 goto done;
1891         iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
1892         if (iml == NULL)
1893                 goto done;
1894
1895         memcpy(&iml->multi, imr, sizeof(*imr));
1896         iml->next_rcu = inet->mc_list;
1897         iml->sflist = NULL;
1898         iml->sfmode = MCAST_EXCLUDE;
1899         rcu_assign_pointer(inet->mc_list, iml);
1900         ip_mc_inc_group(in_dev, addr);
1901         err = 0;
1902 done:
1903         rtnl_unlock();
1904         return err;
1905 }
1906 EXPORT_SYMBOL(ip_mc_join_group);
1907
1908 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
1909                            struct in_device *in_dev)
1910 {
1911         struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
1912         int err;
1913
1914         if (psf == NULL) {
1915                 /* any-source empty exclude case */
1916                 return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1917                         iml->sfmode, 0, NULL, 0);
1918         }
1919         err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
1920                         iml->sfmode, psf->sl_count, psf->sl_addr, 0);
1921         RCU_INIT_POINTER(iml->sflist, NULL);
1922         /* decrease mem now to avoid the memleak warning */
1923         atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc);
1924         kfree_rcu(psf, rcu);
1925         return err;
1926 }
1927
1928 /*
1929  *      Ask a socket to leave a group.
1930  */
1931
1932 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
1933 {
1934         struct inet_sock *inet = inet_sk(sk);
1935         struct ip_mc_socklist *iml;
1936         struct ip_mc_socklist __rcu **imlp;
1937         struct in_device *in_dev;
1938         struct net *net = sock_net(sk);
1939         __be32 group = imr->imr_multiaddr.s_addr;
1940         u32 ifindex;
1941         int ret = -EADDRNOTAVAIL;
1942
1943         rtnl_lock();
1944         in_dev = ip_mc_find_dev(net, imr);
1945         if (!in_dev) {
1946                 ret = -ENODEV;
1947                 goto out;
1948         }
1949         ifindex = imr->imr_ifindex;
1950         for (imlp = &inet->mc_list;
1951              (iml = rtnl_dereference(*imlp)) != NULL;
1952              imlp = &iml->next_rcu) {
1953                 if (iml->multi.imr_multiaddr.s_addr != group)
1954                         continue;
1955                 if (ifindex) {
1956                         if (iml->multi.imr_ifindex != ifindex)
1957                                 continue;
1958                 } else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
1959                                 iml->multi.imr_address.s_addr)
1960                         continue;
1961
1962                 (void) ip_mc_leave_src(sk, iml, in_dev);
1963
1964                 *imlp = iml->next_rcu;
1965
1966                 ip_mc_dec_group(in_dev, group);
1967                 rtnl_unlock();
1968                 /* decrease mem now to avoid the memleak warning */
1969                 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
1970                 kfree_rcu(iml, rcu);
1971                 return 0;
1972         }
1973 out:
1974         rtnl_unlock();
1975         return ret;
1976 }
1977 EXPORT_SYMBOL(ip_mc_leave_group);
1978
1979 int ip_mc_source(int add, int omode, struct sock *sk, struct
1980         ip_mreq_source *mreqs, int ifindex)
1981 {
1982         int err;
1983         struct ip_mreqn imr;
1984         __be32 addr = mreqs->imr_multiaddr;
1985         struct ip_mc_socklist *pmc;
1986         struct in_device *in_dev = NULL;
1987         struct inet_sock *inet = inet_sk(sk);
1988         struct ip_sf_socklist *psl;
1989         struct net *net = sock_net(sk);
1990         int leavegroup = 0;
1991         int i, j, rv;
1992
1993         if (!ipv4_is_multicast(addr))
1994                 return -EINVAL;
1995
1996         rtnl_lock();
1997
1998         imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
1999         imr.imr_address.s_addr = mreqs->imr_interface;
2000         imr.imr_ifindex = ifindex;
2001         in_dev = ip_mc_find_dev(net, &imr);
2002
2003         if (!in_dev) {
2004                 err = -ENODEV;
2005                 goto done;
2006         }
2007         err = -EADDRNOTAVAIL;
2008
2009         for_each_pmc_rtnl(inet, pmc) {
2010                 if ((pmc->multi.imr_multiaddr.s_addr ==
2011                      imr.imr_multiaddr.s_addr) &&
2012                     (pmc->multi.imr_ifindex == imr.imr_ifindex))
2013                         break;
2014         }
2015         if (!pmc) {             /* must have a prior join */
2016                 err = -EINVAL;
2017                 goto done;
2018         }
2019         /* if a source filter was set, must be the same mode as before */
2020         if (pmc->sflist) {
2021                 if (pmc->sfmode != omode) {
2022                         err = -EINVAL;
2023                         goto done;
2024                 }
2025         } else if (pmc->sfmode != omode) {
2026                 /* allow mode switches for empty-set filters */
2027                 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
2028                 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
2029                         NULL, 0);
2030                 pmc->sfmode = omode;
2031         }
2032
2033         psl = rtnl_dereference(pmc->sflist);
2034         if (!add) {
2035                 if (!psl)
2036                         goto done;      /* err = -EADDRNOTAVAIL */
2037                 rv = !0;
2038                 for (i = 0; i < psl->sl_count; i++) {
2039                         rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2040                                 sizeof(__be32));
2041                         if (rv == 0)
2042                                 break;
2043                 }
2044                 if (rv)         /* source not found */
2045                         goto done;      /* err = -EADDRNOTAVAIL */
2046
2047                 /* special case - (INCLUDE, empty) == LEAVE_GROUP */
2048                 if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
2049                         leavegroup = 1;
2050                         goto done;
2051                 }
2052
2053                 /* update the interface filter */
2054                 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2055                         &mreqs->imr_sourceaddr, 1);
2056
2057                 for (j = i+1; j < psl->sl_count; j++)
2058                         psl->sl_addr[j-1] = psl->sl_addr[j];
2059                 psl->sl_count--;
2060                 err = 0;
2061                 goto done;
2062         }
2063         /* else, add a new source to the filter */
2064
2065         if (psl && psl->sl_count >= sysctl_igmp_max_msf) {
2066                 err = -ENOBUFS;
2067                 goto done;
2068         }
2069         if (!psl || psl->sl_count == psl->sl_max) {
2070                 struct ip_sf_socklist *newpsl;
2071                 int count = IP_SFBLOCK;
2072
2073                 if (psl)
2074                         count += psl->sl_max;
2075                 newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
2076                 if (!newpsl) {
2077                         err = -ENOBUFS;
2078                         goto done;
2079                 }
2080                 newpsl->sl_max = count;
2081                 newpsl->sl_count = count - IP_SFBLOCK;
2082                 if (psl) {
2083                         for (i = 0; i < psl->sl_count; i++)
2084                                 newpsl->sl_addr[i] = psl->sl_addr[i];
2085                         /* decrease mem now to avoid the memleak warning */
2086                         atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2087                         kfree_rcu(psl, rcu);
2088                 }
2089                 rcu_assign_pointer(pmc->sflist, newpsl);
2090                 psl = newpsl;
2091         }
2092         rv = 1; /* > 0 for insert logic below if sl_count is 0 */
2093         for (i = 0; i < psl->sl_count; i++) {
2094                 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2095                         sizeof(__be32));
2096                 if (rv == 0)
2097                         break;
2098         }
2099         if (rv == 0)            /* address already there is an error */
2100                 goto done;
2101         for (j = psl->sl_count-1; j >= i; j--)
2102                 psl->sl_addr[j+1] = psl->sl_addr[j];
2103         psl->sl_addr[i] = mreqs->imr_sourceaddr;
2104         psl->sl_count++;
2105         err = 0;
2106         /* update the interface list */
2107         ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2108                 &mreqs->imr_sourceaddr, 1);
2109 done:
2110         rtnl_unlock();
2111         if (leavegroup)
2112                 return ip_mc_leave_group(sk, &imr);
2113         return err;
2114 }
2115
2116 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2117 {
2118         int err = 0;
2119         struct ip_mreqn imr;
2120         __be32 addr = msf->imsf_multiaddr;
2121         struct ip_mc_socklist *pmc;
2122         struct in_device *in_dev;
2123         struct inet_sock *inet = inet_sk(sk);
2124         struct ip_sf_socklist *newpsl, *psl;
2125         struct net *net = sock_net(sk);
2126         int leavegroup = 0;
2127
2128         if (!ipv4_is_multicast(addr))
2129                 return -EINVAL;
2130         if (msf->imsf_fmode != MCAST_INCLUDE &&
2131             msf->imsf_fmode != MCAST_EXCLUDE)
2132                 return -EINVAL;
2133
2134         rtnl_lock();
2135
2136         imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2137         imr.imr_address.s_addr = msf->imsf_interface;
2138         imr.imr_ifindex = ifindex;
2139         in_dev = ip_mc_find_dev(net, &imr);
2140
2141         if (!in_dev) {
2142                 err = -ENODEV;
2143                 goto done;
2144         }
2145
2146         /* special case - (INCLUDE, empty) == LEAVE_GROUP */
2147         if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2148                 leavegroup = 1;
2149                 goto done;
2150         }
2151
2152         for_each_pmc_rtnl(inet, pmc) {
2153                 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2154                     pmc->multi.imr_ifindex == imr.imr_ifindex)
2155                         break;
2156         }
2157         if (!pmc) {             /* must have a prior join */
2158                 err = -EINVAL;
2159                 goto done;
2160         }
2161         if (msf->imsf_numsrc) {
2162                 newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2163                                                            GFP_KERNEL);
2164                 if (!newpsl) {
2165                         err = -ENOBUFS;
2166                         goto done;
2167                 }
2168                 newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2169                 memcpy(newpsl->sl_addr, msf->imsf_slist,
2170                         msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2171                 err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2172                         msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2173                 if (err) {
2174                         sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2175                         goto done;
2176                 }
2177         } else {
2178                 newpsl = NULL;
2179                 (void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2180                                      msf->imsf_fmode, 0, NULL, 0);
2181         }
2182         psl = rtnl_dereference(pmc->sflist);
2183         if (psl) {
2184                 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2185                         psl->sl_count, psl->sl_addr, 0);
2186                 /* decrease mem now to avoid the memleak warning */
2187                 atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2188                 kfree_rcu(psl, rcu);
2189         } else
2190                 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2191                         0, NULL, 0);
2192         rcu_assign_pointer(pmc->sflist, newpsl);
2193         pmc->sfmode = msf->imsf_fmode;
2194         err = 0;
2195 done:
2196         rtnl_unlock();
2197         if (leavegroup)
2198                 err = ip_mc_leave_group(sk, &imr);
2199         return err;
2200 }
2201
2202 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2203         struct ip_msfilter __user *optval, int __user *optlen)
2204 {
2205         int err, len, count, copycount;
2206         struct ip_mreqn imr;
2207         __be32 addr = msf->imsf_multiaddr;
2208         struct ip_mc_socklist *pmc;
2209         struct in_device *in_dev;
2210         struct inet_sock *inet = inet_sk(sk);
2211         struct ip_sf_socklist *psl;
2212         struct net *net = sock_net(sk);
2213
2214         if (!ipv4_is_multicast(addr))
2215                 return -EINVAL;
2216
2217         rtnl_lock();
2218
2219         imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2220         imr.imr_address.s_addr = msf->imsf_interface;
2221         imr.imr_ifindex = 0;
2222         in_dev = ip_mc_find_dev(net, &imr);
2223
2224         if (!in_dev) {
2225                 err = -ENODEV;
2226                 goto done;
2227         }
2228         err = -EADDRNOTAVAIL;
2229
2230         for_each_pmc_rtnl(inet, pmc) {
2231                 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2232                     pmc->multi.imr_ifindex == imr.imr_ifindex)
2233                         break;
2234         }
2235         if (!pmc)               /* must have a prior join */
2236                 goto done;
2237         msf->imsf_fmode = pmc->sfmode;
2238         psl = rtnl_dereference(pmc->sflist);
2239         rtnl_unlock();
2240         if (!psl) {
2241                 len = 0;
2242                 count = 0;
2243         } else {
2244                 count = psl->sl_count;
2245         }
2246         copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2247         len = copycount * sizeof(psl->sl_addr[0]);
2248         msf->imsf_numsrc = count;
2249         if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2250             copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2251                 return -EFAULT;
2252         }
2253         if (len &&
2254             copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2255                 return -EFAULT;
2256         return 0;
2257 done:
2258         rtnl_unlock();
2259         return err;
2260 }
2261
2262 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2263         struct group_filter __user *optval, int __user *optlen)
2264 {
2265         int err, i, count, copycount;
2266         struct sockaddr_in *psin;
2267         __be32 addr;
2268         struct ip_mc_socklist *pmc;
2269         struct inet_sock *inet = inet_sk(sk);
2270         struct ip_sf_socklist *psl;
2271
2272         psin = (struct sockaddr_in *)&gsf->gf_group;
2273         if (psin->sin_family != AF_INET)
2274                 return -EINVAL;
2275         addr = psin->sin_addr.s_addr;
2276         if (!ipv4_is_multicast(addr))
2277                 return -EINVAL;
2278
2279         rtnl_lock();
2280
2281         err = -EADDRNOTAVAIL;
2282
2283         for_each_pmc_rtnl(inet, pmc) {
2284                 if (pmc->multi.imr_multiaddr.s_addr == addr &&
2285                     pmc->multi.imr_ifindex == gsf->gf_interface)
2286                         break;
2287         }
2288         if (!pmc)               /* must have a prior join */
2289                 goto done;
2290         gsf->gf_fmode = pmc->sfmode;
2291         psl = rtnl_dereference(pmc->sflist);
2292         rtnl_unlock();
2293         count = psl ? psl->sl_count : 0;
2294         copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2295         gsf->gf_numsrc = count;
2296         if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2297             copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2298                 return -EFAULT;
2299         }
2300         for (i = 0; i < copycount; i++) {
2301                 struct sockaddr_storage ss;
2302
2303                 psin = (struct sockaddr_in *)&ss;
2304                 memset(&ss, 0, sizeof(ss));
2305                 psin->sin_family = AF_INET;
2306                 psin->sin_addr.s_addr = psl->sl_addr[i];
2307                 if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2308                         return -EFAULT;
2309         }
2310         return 0;
2311 done:
2312         rtnl_unlock();
2313         return err;
2314 }
2315
2316 /*
2317  * check if a multicast source filter allows delivery for a given <src,dst,intf>
2318  */
2319 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif)
2320 {
2321         struct inet_sock *inet = inet_sk(sk);
2322         struct ip_mc_socklist *pmc;
2323         struct ip_sf_socklist *psl;
2324         int i;
2325         int ret;
2326
2327         ret = 1;
2328         if (!ipv4_is_multicast(loc_addr))
2329                 goto out;
2330
2331         rcu_read_lock();
2332         for_each_pmc_rcu(inet, pmc) {
2333                 if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2334                     pmc->multi.imr_ifindex == dif)
2335                         break;
2336         }
2337         ret = inet->mc_all;
2338         if (!pmc)
2339                 goto unlock;
2340         psl = rcu_dereference(pmc->sflist);
2341         ret = (pmc->sfmode == MCAST_EXCLUDE);
2342         if (!psl)
2343                 goto unlock;
2344
2345         for (i = 0; i < psl->sl_count; i++) {
2346                 if (psl->sl_addr[i] == rmt_addr)
2347                         break;
2348         }
2349         ret = 0;
2350         if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2351                 goto unlock;
2352         if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2353                 goto unlock;
2354         ret = 1;
2355 unlock:
2356         rcu_read_unlock();
2357 out:
2358         return ret;
2359 }
2360
2361 /*
2362  *      A socket is closing.
2363  */
2364
2365 void ip_mc_drop_socket(struct sock *sk)
2366 {
2367         struct inet_sock *inet = inet_sk(sk);
2368         struct ip_mc_socklist *iml;
2369         struct net *net = sock_net(sk);
2370
2371         if (inet->mc_list == NULL)
2372                 return;
2373
2374         rtnl_lock();
2375         while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2376                 struct in_device *in_dev;
2377
2378                 inet->mc_list = iml->next_rcu;
2379                 in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2380                 (void) ip_mc_leave_src(sk, iml, in_dev);
2381                 if (in_dev != NULL)
2382                         ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2383                 /* decrease mem now to avoid the memleak warning */
2384                 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2385                 kfree_rcu(iml, rcu);
2386         }
2387         rtnl_unlock();
2388 }
2389
2390 /* called with rcu_read_lock() */
2391 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u16 proto)
2392 {
2393         struct ip_mc_list *im;
2394         struct ip_mc_list __rcu **mc_hash;
2395         struct ip_sf_list *psf;
2396         int rv = 0;
2397
2398         mc_hash = rcu_dereference(in_dev->mc_hash);
2399         if (mc_hash) {
2400                 u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
2401
2402                 for (im = rcu_dereference(mc_hash[hash]);
2403                      im != NULL;
2404                      im = rcu_dereference(im->next_hash)) {
2405                         if (im->multiaddr == mc_addr)
2406                                 break;
2407                 }
2408         } else {
2409                 for_each_pmc_rcu(in_dev, im) {
2410                         if (im->multiaddr == mc_addr)
2411                                 break;
2412                 }
2413         }
2414         if (im && proto == IPPROTO_IGMP) {
2415                 rv = 1;
2416         } else if (im) {
2417                 if (src_addr) {
2418                         for (psf = im->sources; psf; psf = psf->sf_next) {
2419                                 if (psf->sf_inaddr == src_addr)
2420                                         break;
2421                         }
2422                         if (psf)
2423                                 rv = psf->sf_count[MCAST_INCLUDE] ||
2424                                         psf->sf_count[MCAST_EXCLUDE] !=
2425                                         im->sfcount[MCAST_EXCLUDE];
2426                         else
2427                                 rv = im->sfcount[MCAST_EXCLUDE] != 0;
2428                 } else
2429                         rv = 1; /* unspecified source; tentatively allow */
2430         }
2431         return rv;
2432 }
2433
2434 #if defined(CONFIG_PROC_FS)
2435 struct igmp_mc_iter_state {
2436         struct seq_net_private p;
2437         struct net_device *dev;
2438         struct in_device *in_dev;
2439 };
2440
2441 #define igmp_mc_seq_private(seq)        ((struct igmp_mc_iter_state *)(seq)->private)
2442
2443 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2444 {
2445         struct net *net = seq_file_net(seq);
2446         struct ip_mc_list *im = NULL;
2447         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2448
2449         state->in_dev = NULL;
2450         for_each_netdev_rcu(net, state->dev) {
2451                 struct in_device *in_dev;
2452
2453                 in_dev = __in_dev_get_rcu(state->dev);
2454                 if (!in_dev)
2455                         continue;
2456                 im = rcu_dereference(in_dev->mc_list);
2457                 if (im) {
2458                         state->in_dev = in_dev;
2459                         break;
2460                 }
2461         }
2462         return im;
2463 }
2464
2465 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2466 {
2467         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2468
2469         im = rcu_dereference(im->next_rcu);
2470         while (!im) {
2471                 state->dev = next_net_device_rcu(state->dev);
2472                 if (!state->dev) {
2473                         state->in_dev = NULL;
2474                         break;
2475                 }
2476                 state->in_dev = __in_dev_get_rcu(state->dev);
2477                 if (!state->in_dev)
2478                         continue;
2479                 im = rcu_dereference(state->in_dev->mc_list);
2480         }
2481         return im;
2482 }
2483
2484 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2485 {
2486         struct ip_mc_list *im = igmp_mc_get_first(seq);
2487         if (im)
2488                 while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2489                         --pos;
2490         return pos ? NULL : im;
2491 }
2492
2493 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2494         __acquires(rcu)
2495 {
2496         rcu_read_lock();
2497         return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2498 }
2499
2500 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2501 {
2502         struct ip_mc_list *im;
2503         if (v == SEQ_START_TOKEN)
2504                 im = igmp_mc_get_first(seq);
2505         else
2506                 im = igmp_mc_get_next(seq, v);
2507         ++*pos;
2508         return im;
2509 }
2510
2511 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2512         __releases(rcu)
2513 {
2514         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2515
2516         state->in_dev = NULL;
2517         state->dev = NULL;
2518         rcu_read_unlock();
2519 }
2520
2521 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2522 {
2523         if (v == SEQ_START_TOKEN)
2524                 seq_puts(seq,
2525                          "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2526         else {
2527                 struct ip_mc_list *im = (struct ip_mc_list *)v;
2528                 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2529                 char   *querier;
2530                 long delta;
2531
2532 #ifdef CONFIG_IP_MULTICAST
2533                 querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2534                           IGMP_V2_SEEN(state->in_dev) ? "V2" :
2535                           "V3";
2536 #else
2537                 querier = "NONE";
2538 #endif
2539
2540                 if (rcu_access_pointer(state->in_dev->mc_list) == im) {
2541                         seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2542                                    state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2543                 }
2544
2545                 delta = im->timer.expires - jiffies;
2546                 seq_printf(seq,
2547                            "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2548                            im->multiaddr, im->users,
2549                            im->tm_running,
2550                            im->tm_running ? jiffies_delta_to_clock_t(delta) : 0,
2551                            im->reporter);
2552         }
2553         return 0;
2554 }
2555
2556 static const struct seq_operations igmp_mc_seq_ops = {
2557         .start  =       igmp_mc_seq_start,
2558         .next   =       igmp_mc_seq_next,
2559         .stop   =       igmp_mc_seq_stop,
2560         .show   =       igmp_mc_seq_show,
2561 };
2562
2563 static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2564 {
2565         return seq_open_net(inode, file, &igmp_mc_seq_ops,
2566                         sizeof(struct igmp_mc_iter_state));
2567 }
2568
2569 static const struct file_operations igmp_mc_seq_fops = {
2570         .owner          =       THIS_MODULE,
2571         .open           =       igmp_mc_seq_open,
2572         .read           =       seq_read,
2573         .llseek         =       seq_lseek,
2574         .release        =       seq_release_net,
2575 };
2576
2577 struct igmp_mcf_iter_state {
2578         struct seq_net_private p;
2579         struct net_device *dev;
2580         struct in_device *idev;
2581         struct ip_mc_list *im;
2582 };
2583
2584 #define igmp_mcf_seq_private(seq)       ((struct igmp_mcf_iter_state *)(seq)->private)
2585
2586 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2587 {
2588         struct net *net = seq_file_net(seq);
2589         struct ip_sf_list *psf = NULL;
2590         struct ip_mc_list *im = NULL;
2591         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2592
2593         state->idev = NULL;
2594         state->im = NULL;
2595         for_each_netdev_rcu(net, state->dev) {
2596                 struct in_device *idev;
2597                 idev = __in_dev_get_rcu(state->dev);
2598                 if (unlikely(idev == NULL))
2599                         continue;
2600                 im = rcu_dereference(idev->mc_list);
2601                 if (likely(im != NULL)) {
2602                         spin_lock_bh(&im->lock);
2603                         psf = im->sources;
2604                         if (likely(psf != NULL)) {
2605                                 state->im = im;
2606                                 state->idev = idev;
2607                                 break;
2608                         }
2609                         spin_unlock_bh(&im->lock);
2610                 }
2611         }
2612         return psf;
2613 }
2614
2615 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2616 {
2617         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2618
2619         psf = psf->sf_next;
2620         while (!psf) {
2621                 spin_unlock_bh(&state->im->lock);
2622                 state->im = state->im->next;
2623                 while (!state->im) {
2624                         state->dev = next_net_device_rcu(state->dev);
2625                         if (!state->dev) {
2626                                 state->idev = NULL;
2627                                 goto out;
2628                         }
2629                         state->idev = __in_dev_get_rcu(state->dev);
2630                         if (!state->idev)
2631                                 continue;
2632                         state->im = rcu_dereference(state->idev->mc_list);
2633                 }
2634                 if (!state->im)
2635                         break;
2636                 spin_lock_bh(&state->im->lock);
2637                 psf = state->im->sources;
2638         }
2639 out:
2640         return psf;
2641 }
2642
2643 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2644 {
2645         struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2646         if (psf)
2647                 while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2648                         --pos;
2649         return pos ? NULL : psf;
2650 }
2651
2652 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2653         __acquires(rcu)
2654 {
2655         rcu_read_lock();
2656         return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2657 }
2658
2659 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2660 {
2661         struct ip_sf_list *psf;
2662         if (v == SEQ_START_TOKEN)
2663                 psf = igmp_mcf_get_first(seq);
2664         else
2665                 psf = igmp_mcf_get_next(seq, v);
2666         ++*pos;
2667         return psf;
2668 }
2669
2670 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2671         __releases(rcu)
2672 {
2673         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2674         if (likely(state->im != NULL)) {
2675                 spin_unlock_bh(&state->im->lock);
2676                 state->im = NULL;
2677         }
2678         state->idev = NULL;
2679         state->dev = NULL;
2680         rcu_read_unlock();
2681 }
2682
2683 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2684 {
2685         struct ip_sf_list *psf = (struct ip_sf_list *)v;
2686         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2687
2688         if (v == SEQ_START_TOKEN) {
2689                 seq_printf(seq,
2690                            "%3s %6s "
2691                            "%10s %10s %6s %6s\n", "Idx",
2692                            "Device", "MCA",
2693                            "SRC", "INC", "EXC");
2694         } else {
2695                 seq_printf(seq,
2696                            "%3d %6.6s 0x%08x "
2697                            "0x%08x %6lu %6lu\n",
2698                            state->dev->ifindex, state->dev->name,
2699                            ntohl(state->im->multiaddr),
2700                            ntohl(psf->sf_inaddr),
2701                            psf->sf_count[MCAST_INCLUDE],
2702                            psf->sf_count[MCAST_EXCLUDE]);
2703         }
2704         return 0;
2705 }
2706
2707 static const struct seq_operations igmp_mcf_seq_ops = {
2708         .start  =       igmp_mcf_seq_start,
2709         .next   =       igmp_mcf_seq_next,
2710         .stop   =       igmp_mcf_seq_stop,
2711         .show   =       igmp_mcf_seq_show,
2712 };
2713
2714 static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2715 {
2716         return seq_open_net(inode, file, &igmp_mcf_seq_ops,
2717                         sizeof(struct igmp_mcf_iter_state));
2718 }
2719
2720 static const struct file_operations igmp_mcf_seq_fops = {
2721         .owner          =       THIS_MODULE,
2722         .open           =       igmp_mcf_seq_open,
2723         .read           =       seq_read,
2724         .llseek         =       seq_lseek,
2725         .release        =       seq_release_net,
2726 };
2727
2728 static int __net_init igmp_net_init(struct net *net)
2729 {
2730         struct proc_dir_entry *pde;
2731
2732         pde = proc_create("igmp", S_IRUGO, net->proc_net, &igmp_mc_seq_fops);
2733         if (!pde)
2734                 goto out_igmp;
2735         pde = proc_create("mcfilter", S_IRUGO, net->proc_net,
2736                           &igmp_mcf_seq_fops);
2737         if (!pde)
2738                 goto out_mcfilter;
2739         return 0;
2740
2741 out_mcfilter:
2742         remove_proc_entry("igmp", net->proc_net);
2743 out_igmp:
2744         return -ENOMEM;
2745 }
2746
2747 static void __net_exit igmp_net_exit(struct net *net)
2748 {
2749         remove_proc_entry("mcfilter", net->proc_net);
2750         remove_proc_entry("igmp", net->proc_net);
2751 }
2752
2753 static struct pernet_operations igmp_net_ops = {
2754         .init = igmp_net_init,
2755         .exit = igmp_net_exit,
2756 };
2757 #endif
2758
2759 static int igmp_netdev_event(struct notifier_block *this,
2760                              unsigned long event, void *ptr)
2761 {
2762         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2763         struct in_device *in_dev;
2764
2765         switch (event) {
2766         case NETDEV_RESEND_IGMP:
2767                 in_dev = __in_dev_get_rtnl(dev);
2768                 if (in_dev)
2769                         ip_mc_rejoin_groups(in_dev);
2770                 break;
2771         default:
2772                 break;
2773         }
2774         return NOTIFY_DONE;
2775 }
2776
2777 static struct notifier_block igmp_notifier = {
2778         .notifier_call = igmp_netdev_event,
2779 };
2780
2781 int __init igmp_mc_init(void)
2782 {
2783 #if defined(CONFIG_PROC_FS)
2784         int err;
2785
2786         err = register_pernet_subsys(&igmp_net_ops);
2787         if (err)
2788                 return err;
2789         err = register_netdevice_notifier(&igmp_notifier);
2790         if (err)
2791                 goto reg_notif_fail;
2792         return 0;
2793
2794 reg_notif_fail:
2795         unregister_pernet_subsys(&igmp_net_ops);
2796         return err;
2797 #else
2798         return register_netdevice_notifier(&igmp_notifier);
2799 #endif
2800 }