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