net/ipv4/igmp.c

   1 /*
   2  *      Linux NET3:     Internet Group Management Protocol  [IGMP]
   3  *
   4  *      This code implements the IGMP protocol as defined in RFC1112. There has
   5  *      been a further revision of this protocol since which is now supported.
   6  *
   7  *      If you have trouble with this module be careful what gcc you have used,
   8  *      the older version didn't come out right using gcc 2.5.8, the newer one
   9  *      seems to fall out with gcc 2.6.2.
  10  *
  11  *      Authors:
  12  *              Alan Cox <alan@lxorguk.ukuu.org.uk>
  13  *
  14  *      This program is free software; you can redistribute it and/or
  15  *      modify it under the terms of the GNU General Public License
  16  *      as published by the Free Software Foundation; either version
  17  *      2 of the License, or (at your option) any later version.
  18  *
  19  *      Fixes:
  20  *
  21  *              Alan Cox        :       Added lots of __inline__ to optimise
  22  *                                      the memory usage of all the tiny little
  23  *                                      functions.
  24  *              Alan Cox        :       Dumped the header building experiment.
  25  *              Alan Cox        :       Minor tweaks ready for multicast routing
  26  *                                      and extended IGMP protocol.
  27  *              Alan Cox        :       Removed a load of inline directives. Gcc 2.5.8
  28  *                                      writes utterly bogus code otherwise (sigh)
  29  *                                      fixed IGMP loopback to behave in the manner
  30  *                                      desired by mrouted, fixed the fact it has been
  31  *                                      broken since 1.3.6 and cleaned up a few minor
  32  *                                      points.
  33  *
  34  *              Chih-Jen Chang  :       Tried to revise IGMP to Version 2
  35  *              Tsu-Sheng Tsao          E-mail: chihjenc@scf.usc.edu and tsusheng@scf.usc.edu
  36  *                                      The enhancements are mainly based on Steve Deering's
  37  *                                      ipmulti-3.5 source code.
  38  *              Chih-Jen Chang  :       Added the igmp_get_mrouter_info and
  39  *              Tsu-Sheng Tsao          igmp_set_mrouter_info to keep track of
  40  *                                      the mrouted version on that device.
  41  *              Chih-Jen Chang  :       Added the max_resp_time parameter to
  42  *              Tsu-Sheng Tsao          igmp_heard_query(). Using this parameter
  43  *                                      to identify the multicast router version
  44  *                                      and do what the IGMP version 2 specified.
  45  *              Chih-Jen Chang  :       Added a timer to revert to IGMP V2 router
  46  *              Tsu-Sheng Tsao          if the specified time expired.
  47  *              Alan Cox        :       Stop IGMP from 0.0.0.0 being accepted.
  48  *              Alan Cox        :       Use GFP_ATOMIC in the right places.
  49  *              Christian Daudt :       igmp timer wasn't set for local group
  50  *                                      memberships but was being deleted,
  51  *                                      which caused a "del_timer() called
  52  *                                      from %p with timer not initialized\n"
  53  *                                      message (960131).
  54  *              Christian Daudt :       removed del_timer from
  55  *                                      igmp_timer_expire function (960205).
  56  *             Christian Daudt :       igmp_heard_report now only calls
  57  *                                     igmp_timer_expire if tm->running is
  58  *                                     true (960216).
  59  *              Malcolm Beattie :       ttl comparison wrong in igmp_rcv made
  60  *                                      igmp_heard_query never trigger. Expiry
  61  *                                      miscalculation fixed in igmp_heard_query
  62  *                                      and random() made to return unsigned to
  63  *                                      prevent negative expiry times.
  64  *              Alexey Kuznetsov:       Wrong group leaving behaviour, backport
  65  *                                      fix from pending 2.1.x patches.
  66  *              Alan Cox:               Forget to enable FDDI support earlier.
  67  *              Alexey Kuznetsov:       Fixed leaving groups on device down.
  68  *              Alexey Kuznetsov:       Accordance to igmp-v2-06 draft.
  69  *              David L Stevens:        IGMPv3 support, with help from
  70  *                                      Vinay Kulkarni
  71  */
  72
  73 #include <linux/module.h>
  74 #include <linux/slab.h>
  75 #include <linux/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 #ifdef CONFIG_IP_MULTICAST
 111 /* Parameter names and values are taken from igmp-v2-06 draft */
 112
 113 #define IGMP_V1_ROUTER_PRESENT_TIMEOUT          (400*HZ)
 114 #define IGMP_V2_ROUTER_PRESENT_TIMEOUT          (400*HZ)
 115 #define IGMP_V2_UNSOLICITED_REPORT_INTERVAL     (10*HZ)
 116 #define IGMP_V3_UNSOLICITED_REPORT_INTERVAL     (1*HZ)
 117 #define IGMP_QUERY_RESPONSE_INTERVAL            (10*HZ)
 118 #define IGMP_QUERY_ROBUSTNESS_VARIABLE          2
 119
 120
 121 #define IGMP_INITIAL_REPORT_DELAY               (1)
 122
 123 /* IGMP_INITIAL_REPORT_DELAY is not from IGMP specs!
 124  * IGMP specs require to report membership immediately after
 125  * joining a group, but we delay the first report by a
 126  * small interval. It seems more natural and still does not
 127  * contradict to specs provided this delay is small enough.
 128  */
 129
 130 #define IGMP_V1_SEEN(in_dev) \
 131         (IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \
 132          IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \
 133          ((in_dev)->mr_v1_seen && \
 134           time_before(jiffies, (in_dev)->mr_v1_seen)))
 135 #define IGMP_V2_SEEN(in_dev) \
 136         (IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \
 137          IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \
 138          ((in_dev)->mr_v2_seen && \
 139           time_before(jiffies, (in_dev)->mr_v2_seen)))
 140
 141 static int unsolicited_report_interval(struct in_device *in_dev)
 142 {
 143         int interval_ms, interval_jiffies;
 144
 145         if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 146                 interval_ms = IN_DEV_CONF_GET(
 147                         in_dev,
 148                         IGMPV2_UNSOLICITED_REPORT_INTERVAL);
 149         else /* v3 */
 150                 interval_ms = IN_DEV_CONF_GET(
 151                         in_dev,
 152                         IGMPV3_UNSOLICITED_REPORT_INTERVAL);
 153
 154         interval_jiffies = msecs_to_jiffies(interval_ms);
 155
 156         /* _timer functions can't handle a delay of 0 jiffies so ensure
 157          *  we always return a positive value.
 158          */
 159         if (interval_jiffies <= 0)
 160                 interval_jiffies = 1;
 161         return interval_jiffies;
 162 }
 163
 164 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im);
 165 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im);
 166 static void igmpv3_clear_delrec(struct in_device *in_dev);
 167 static int sf_setstate(struct ip_mc_list *pmc);
 168 static void sf_markstate(struct ip_mc_list *pmc);
 169 #endif
 170 static void ip_mc_clear_src(struct ip_mc_list *pmc);
 171 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
 172                          int sfcount, __be32 *psfsrc, int delta);
 173
 174 static void ip_ma_put(struct ip_mc_list *im)
 175 {
 176         if (refcount_dec_and_test(&im->refcnt)) {
 177                 in_dev_put(im->interface);
 178                 kfree_rcu(im, rcu);
 179         }
 180 }
 181
 182 #define for_each_pmc_rcu(in_dev, pmc)                           \
 183         for (pmc = rcu_dereference(in_dev->mc_list);            \
 184              pmc != NULL;                                       \
 185              pmc = rcu_dereference(pmc->next_rcu))
 186
 187 #define for_each_pmc_rtnl(in_dev, pmc)                          \
 188         for (pmc = rtnl_dereference(in_dev->mc_list);           \
 189              pmc != NULL;                                       \
 190              pmc = rtnl_dereference(pmc->next_rcu))
 191
 192 #ifdef CONFIG_IP_MULTICAST
 193
 194 /*
 195  *      Timer management
 196  */
 197
 198 static void igmp_stop_timer(struct ip_mc_list *im)
 199 {
 200         spin_lock_bh(&im->lock);
 201         if (del_timer(&im->timer))
 202                 refcount_dec(&im->refcnt);
 203         im->tm_running = 0;
 204         im->reporter = 0;
 205         im->unsolicit_count = 0;
 206         spin_unlock_bh(&im->lock);
 207 }
 208
 209 /* It must be called with locked im->lock */
 210 static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
 211 {
 212         int tv = prandom_u32() % max_delay;
 213
 214         im->tm_running = 1;
 215         if (!mod_timer(&im->timer, jiffies+tv+2))
 216                 refcount_inc(&im->refcnt);
 217 }
 218
 219 static void igmp_gq_start_timer(struct in_device *in_dev)
 220 {
 221         int tv = prandom_u32() % in_dev->mr_maxdelay;
 222         unsigned long exp = jiffies + tv + 2;
 223
 224         if (in_dev->mr_gq_running &&
 225             time_after_eq(exp, (in_dev->mr_gq_timer).expires))
 226                 return;
 227
 228         in_dev->mr_gq_running = 1;
 229         if (!mod_timer(&in_dev->mr_gq_timer, exp))
 230                 in_dev_hold(in_dev);
 231 }
 232
 233 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
 234 {
 235         int tv = prandom_u32() % delay;
 236
 237         if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
 238                 in_dev_hold(in_dev);
 239 }
 240
 241 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
 242 {
 243         spin_lock_bh(&im->lock);
 244         im->unsolicit_count = 0;
 245         if (del_timer(&im->timer)) {
 246                 if ((long)(im->timer.expires-jiffies) < max_delay) {
 247                         add_timer(&im->timer);
 248                         im->tm_running = 1;
 249                         spin_unlock_bh(&im->lock);
 250                         return;
 251                 }
 252                 refcount_dec(&im->refcnt);
 253         }
 254         igmp_start_timer(im, max_delay);
 255         spin_unlock_bh(&im->lock);
 256 }
 257
 258
 259 /*
 260  *      Send an IGMP report.
 261  */
 262
 263 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
 264
 265
 266 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
 267         int gdeleted, int sdeleted)
 268 {
 269         switch (type) {
 270         case IGMPV3_MODE_IS_INCLUDE:
 271         case IGMPV3_MODE_IS_EXCLUDE:
 272                 if (gdeleted || sdeleted)
 273                         return 0;
 274                 if (!(pmc->gsquery && !psf->sf_gsresp)) {
 275                         if (pmc->sfmode == MCAST_INCLUDE)
 276                                 return 1;
 277                         /* don't include if this source is excluded
 278                          * in all filters
 279                          */
 280                         if (psf->sf_count[MCAST_INCLUDE])
 281                                 return type == IGMPV3_MODE_IS_INCLUDE;
 282                         return pmc->sfcount[MCAST_EXCLUDE] ==
 283                                 psf->sf_count[MCAST_EXCLUDE];
 284                 }
 285                 return 0;
 286         case IGMPV3_CHANGE_TO_INCLUDE:
 287                 if (gdeleted || sdeleted)
 288                         return 0;
 289                 return psf->sf_count[MCAST_INCLUDE] != 0;
 290         case IGMPV3_CHANGE_TO_EXCLUDE:
 291                 if (gdeleted || sdeleted)
 292                         return 0;
 293                 if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
 294                     psf->sf_count[MCAST_INCLUDE])
 295                         return 0;
 296                 return pmc->sfcount[MCAST_EXCLUDE] ==
 297                         psf->sf_count[MCAST_EXCLUDE];
 298         case IGMPV3_ALLOW_NEW_SOURCES:
 299                 if (gdeleted || !psf->sf_crcount)
 300                         return 0;
 301                 return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
 302         case IGMPV3_BLOCK_OLD_SOURCES:
 303                 if (pmc->sfmode == MCAST_INCLUDE)
 304                         return gdeleted || (psf->sf_crcount && sdeleted);
 305                 return psf->sf_crcount && !gdeleted && !sdeleted;
 306         }
 307         return 0;
 308 }
 309
 310 static int
 311 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
 312 {
 313         struct ip_sf_list *psf;
 314         int scount = 0;
 315
 316         for (psf = pmc->sources; psf; psf = psf->sf_next) {
 317                 if (!is_in(pmc, psf, type, gdeleted, sdeleted))
 318                         continue;
 319                 scount++;
 320         }
 321         return scount;
 322 }
 323
 324 static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
 325 {
 326         struct sk_buff *skb;
 327         struct rtable *rt;
 328         struct iphdr *pip;
 329         struct igmpv3_report *pig;
 330         struct net *net = dev_net(dev);
 331         struct flowi4 fl4;
 332         int hlen = LL_RESERVED_SPACE(dev);
 333         int tlen = dev->needed_tailroom;
 334         unsigned int size = mtu;
 335
 336         while (1) {
 337                 skb = alloc_skb(size + hlen + tlen,
 338                                 GFP_ATOMIC | __GFP_NOWARN);
 339                 if (skb)
 340                         break;
 341                 size >>= 1;
 342                 if (size < 256)
 343                         return NULL;
 344         }
 345         skb->priority = TC_PRIO_CONTROL;
 346
 347         rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0,
 348                                    0, 0,
 349                                    IPPROTO_IGMP, 0, dev->ifindex);
 350         if (IS_ERR(rt)) {
 351                 kfree_skb(skb);
 352                 return NULL;
 353         }
 354
 355         skb_dst_set(skb, &rt->dst);
 356         skb->dev = dev;
 357
 358         skb_reserve(skb, hlen);
 359         skb_tailroom_reserve(skb, mtu, tlen);
 360
 361         skb_reset_network_header(skb);
 362         pip = ip_hdr(skb);
 363         skb_put(skb, sizeof(struct iphdr) + 4);
 364
 365         pip->version  = 4;
 366         pip->ihl      = (sizeof(struct iphdr)+4)>>2;
 367         pip->tos      = 0xc0;
 368         pip->frag_off = htons(IP_DF);
 369         pip->ttl      = 1;
 370         pip->daddr    = fl4.daddr;
 371         pip->saddr    = fl4.saddr;
 372         pip->protocol = IPPROTO_IGMP;
 373         pip->tot_len  = 0;      /* filled in later */
 374         ip_select_ident(net, skb, NULL);
 375         ((u8 *)&pip[1])[0] = IPOPT_RA;
 376         ((u8 *)&pip[1])[1] = 4;
 377         ((u8 *)&pip[1])[2] = 0;
 378         ((u8 *)&pip[1])[3] = 0;
 379
 380         skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
 381         skb_put(skb, sizeof(*pig));
 382         pig = igmpv3_report_hdr(skb);
 383         pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
 384         pig->resv1 = 0;
 385         pig->csum = 0;
 386         pig->resv2 = 0;
 387         pig->ngrec = 0;
 388         return skb;
 389 }
 390
 391 static int igmpv3_sendpack(struct sk_buff *skb)
 392 {
 393         struct igmphdr *pig = igmp_hdr(skb);
 394         const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
 395
 396         pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
 397
 398         return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
 399 }
 400
 401 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
 402 {
 403         return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
 404 }
 405
 406 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
 407         int type, struct igmpv3_grec **ppgr)
 408 {
 409         struct net_device *dev = pmc->interface->dev;
 410         struct igmpv3_report *pih;
 411         struct igmpv3_grec *pgr;
 412
 413         if (!skb)
 414                 skb = igmpv3_newpack(dev, dev->mtu);
 415         if (!skb)
 416                 return NULL;
 417         pgr = skb_put(skb, sizeof(struct igmpv3_grec));
 418         pgr->grec_type = type;
 419         pgr->grec_auxwords = 0;
 420         pgr->grec_nsrcs = 0;
 421         pgr->grec_mca = pmc->multiaddr;
 422         pih = igmpv3_report_hdr(skb);
 423         pih->ngrec = htons(ntohs(pih->ngrec)+1);
 424         *ppgr = pgr;
 425         return skb;
 426 }
 427
 428 #define AVAILABLE(skb)  ((skb) ? skb_availroom(skb) : 0)
 429
 430 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
 431         int type, int gdeleted, int sdeleted)
 432 {
 433         struct net_device *dev = pmc->interface->dev;
 434         struct net *net = dev_net(dev);
 435         struct igmpv3_report *pih;
 436         struct igmpv3_grec *pgr = NULL;
 437         struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
 438         int scount, stotal, first, isquery, truncate;
 439
 440         if (pmc->multiaddr == IGMP_ALL_HOSTS)
 441                 return skb;
 442         if (ipv4_is_local_multicast(pmc->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
 443                 return skb;
 444
 445         isquery = type == IGMPV3_MODE_IS_INCLUDE ||
 446                   type == IGMPV3_MODE_IS_EXCLUDE;
 447         truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
 448                     type == IGMPV3_CHANGE_TO_EXCLUDE;
 449
 450         stotal = scount = 0;
 451
 452         psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
 453
 454         if (!*psf_list)
 455                 goto empty_source;
 456
 457         pih = skb ? igmpv3_report_hdr(skb) : NULL;
 458
 459         /* EX and TO_EX get a fresh packet, if needed */
 460         if (truncate) {
 461                 if (pih && pih->ngrec &&
 462                     AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
 463                         if (skb)
 464                                 igmpv3_sendpack(skb);
 465                         skb = igmpv3_newpack(dev, dev->mtu);
 466                 }
 467         }
 468         first = 1;
 469         psf_prev = NULL;
 470         for (psf = *psf_list; psf; psf = psf_next) {
 471                 __be32 *psrc;
 472
 473                 psf_next = psf->sf_next;
 474
 475                 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
 476                         psf_prev = psf;
 477                         continue;
 478                 }
 479
 480                 /* Based on RFC3376 5.1. Should not send source-list change
 481                  * records when there is a filter mode change.
 482                  */
 483                 if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) ||
 484                      (!gdeleted && pmc->crcount)) &&
 485                     (type == IGMPV3_ALLOW_NEW_SOURCES ||
 486                      type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount)
 487                         goto decrease_sf_crcount;
 488
 489                 /* clear marks on query responses */
 490                 if (isquery)
 491                         psf->sf_gsresp = 0;
 492
 493                 if (AVAILABLE(skb) < sizeof(__be32) +
 494                     first*sizeof(struct igmpv3_grec)) {
 495                         if (truncate && !first)
 496                                 break;   /* truncate these */
 497                         if (pgr)
 498                                 pgr->grec_nsrcs = htons(scount);
 499                         if (skb)
 500                                 igmpv3_sendpack(skb);
 501                         skb = igmpv3_newpack(dev, dev->mtu);
 502                         first = 1;
 503                         scount = 0;
 504                 }
 505                 if (first) {
 506                         skb = add_grhead(skb, pmc, type, &pgr);
 507                         first = 0;
 508                 }
 509                 if (!skb)
 510                         return NULL;
 511                 psrc = skb_put(skb, sizeof(__be32));
 512                 *psrc = psf->sf_inaddr;
 513                 scount++; stotal++;
 514                 if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
 515                      type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
 516 decrease_sf_crcount:
 517                         psf->sf_crcount--;
 518                         if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
 519                                 if (psf_prev)
 520                                         psf_prev->sf_next = psf->sf_next;
 521                                 else
 522                                         *psf_list = psf->sf_next;
 523                                 kfree(psf);
 524                                 continue;
 525                         }
 526                 }
 527                 psf_prev = psf;
 528         }
 529
 530 empty_source:
 531         if (!stotal) {
 532                 if (type == IGMPV3_ALLOW_NEW_SOURCES ||
 533                     type == IGMPV3_BLOCK_OLD_SOURCES)
 534                         return skb;
 535                 if (pmc->crcount || isquery) {
 536                         /* make sure we have room for group header */
 537                         if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) {
 538                                 igmpv3_sendpack(skb);
 539                                 skb = NULL; /* add_grhead will get a new one */
 540                         }
 541                         skb = add_grhead(skb, pmc, type, &pgr);
 542                 }
 543         }
 544         if (pgr)
 545                 pgr->grec_nsrcs = htons(scount);
 546
 547         if (isquery)
 548                 pmc->gsquery = 0;       /* clear query state on report */
 549         return skb;
 550 }
 551
 552 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
 553 {
 554         struct sk_buff *skb = NULL;
 555         struct net *net = dev_net(in_dev->dev);
 556         int type;
 557
 558         if (!pmc) {
 559                 rcu_read_lock();
 560                 for_each_pmc_rcu(in_dev, pmc) {
 561                         if (pmc->multiaddr == IGMP_ALL_HOSTS)
 562                                 continue;
 563                         if (ipv4_is_local_multicast(pmc->multiaddr) &&
 564                              !net->ipv4.sysctl_igmp_llm_reports)
 565                                 continue;
 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                 rcu_read_unlock();
 575         } else {
 576                 spin_lock_bh(&pmc->lock);
 577                 if (pmc->sfcount[MCAST_EXCLUDE])
 578                         type = IGMPV3_MODE_IS_EXCLUDE;
 579                 else
 580                         type = IGMPV3_MODE_IS_INCLUDE;
 581                 skb = add_grec(skb, pmc, type, 0, 0);
 582                 spin_unlock_bh(&pmc->lock);
 583         }
 584         if (!skb)
 585                 return 0;
 586         return igmpv3_sendpack(skb);
 587 }
 588
 589 /*
 590  * remove zero-count source records from a source filter list
 591  */
 592 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
 593 {
 594         struct ip_sf_list *psf_prev, *psf_next, *psf;
 595
 596         psf_prev = NULL;
 597         for (psf = *ppsf; psf; psf = psf_next) {
 598                 psf_next = psf->sf_next;
 599                 if (psf->sf_crcount == 0) {
 600                         if (psf_prev)
 601                                 psf_prev->sf_next = psf->sf_next;
 602                         else
 603                                 *ppsf = psf->sf_next;
 604                         kfree(psf);
 605                 } else
 606                         psf_prev = psf;
 607         }
 608 }
 609
 610 static void igmpv3_send_cr(struct in_device *in_dev)
 611 {
 612         struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
 613         struct sk_buff *skb = NULL;
 614         int type, dtype;
 615
 616         rcu_read_lock();
 617         spin_lock_bh(&in_dev->mc_tomb_lock);
 618
 619         /* deleted MCA's */
 620         pmc_prev = NULL;
 621         for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) {
 622                 pmc_next = pmc->next;
 623                 if (pmc->sfmode == MCAST_INCLUDE) {
 624                         type = IGMPV3_BLOCK_OLD_SOURCES;
 625                         dtype = IGMPV3_BLOCK_OLD_SOURCES;
 626                         skb = add_grec(skb, pmc, type, 1, 0);
 627                         skb = add_grec(skb, pmc, dtype, 1, 1);
 628                 }
 629                 if (pmc->crcount) {
 630                         if (pmc->sfmode == MCAST_EXCLUDE) {
 631                                 type = IGMPV3_CHANGE_TO_INCLUDE;
 632                                 skb = add_grec(skb, pmc, type, 1, 0);
 633                         }
 634                         pmc->crcount--;
 635                         if (pmc->crcount == 0) {
 636                                 igmpv3_clear_zeros(&pmc->tomb);
 637                                 igmpv3_clear_zeros(&pmc->sources);
 638                         }
 639                 }
 640                 if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
 641                         if (pmc_prev)
 642                                 pmc_prev->next = pmc_next;
 643                         else
 644                                 in_dev->mc_tomb = pmc_next;
 645                         in_dev_put(pmc->interface);
 646                         kfree(pmc);
 647                 } else
 648                         pmc_prev = pmc;
 649         }
 650         spin_unlock_bh(&in_dev->mc_tomb_lock);
 651
 652         /* change recs */
 653         for_each_pmc_rcu(in_dev, pmc) {
 654                 spin_lock_bh(&pmc->lock);
 655                 if (pmc->sfcount[MCAST_EXCLUDE]) {
 656                         type = IGMPV3_BLOCK_OLD_SOURCES;
 657                         dtype = IGMPV3_ALLOW_NEW_SOURCES;
 658                 } else {
 659                         type = IGMPV3_ALLOW_NEW_SOURCES;
 660                         dtype = IGMPV3_BLOCK_OLD_SOURCES;
 661                 }
 662                 skb = add_grec(skb, pmc, type, 0, 0);
 663                 skb = add_grec(skb, pmc, dtype, 0, 1);  /* deleted sources */
 664
 665                 /* filter mode changes */
 666                 if (pmc->crcount) {
 667                         if (pmc->sfmode == MCAST_EXCLUDE)
 668                                 type = IGMPV3_CHANGE_TO_EXCLUDE;
 669                         else
 670                                 type = IGMPV3_CHANGE_TO_INCLUDE;
 671                         skb = add_grec(skb, pmc, type, 0, 0);
 672                         pmc->crcount--;
 673                 }
 674                 spin_unlock_bh(&pmc->lock);
 675         }
 676         rcu_read_unlock();
 677
 678         if (!skb)
 679                 return;
 680         (void) igmpv3_sendpack(skb);
 681 }
 682
 683 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
 684         int type)
 685 {
 686         struct sk_buff *skb;
 687         struct iphdr *iph;
 688         struct igmphdr *ih;
 689         struct rtable *rt;
 690         struct net_device *dev = in_dev->dev;
 691         struct net *net = dev_net(dev);
 692         __be32  group = pmc ? pmc->multiaddr : 0;
 693         struct flowi4 fl4;
 694         __be32  dst;
 695         int hlen, tlen;
 696
 697         if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
 698                 return igmpv3_send_report(in_dev, pmc);
 699
 700         if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
 701                 return 0;
 702
 703         if (type == IGMP_HOST_LEAVE_MESSAGE)
 704                 dst = IGMP_ALL_ROUTER;
 705         else
 706                 dst = group;
 707
 708         rt = ip_route_output_ports(net, &fl4, NULL, dst, 0,
 709                                    0, 0,
 710                                    IPPROTO_IGMP, 0, dev->ifindex);
 711         if (IS_ERR(rt))
 712                 return -1;
 713
 714         hlen = LL_RESERVED_SPACE(dev);
 715         tlen = dev->needed_tailroom;
 716         skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC);
 717         if (!skb) {
 718                 ip_rt_put(rt);
 719                 return -1;
 720         }
 721         skb->priority = TC_PRIO_CONTROL;
 722
 723         skb_dst_set(skb, &rt->dst);
 724
 725         skb_reserve(skb, hlen);
 726
 727         skb_reset_network_header(skb);
 728         iph = ip_hdr(skb);
 729         skb_put(skb, sizeof(struct iphdr) + 4);
 730
 731         iph->version  = 4;
 732         iph->ihl      = (sizeof(struct iphdr)+4)>>2;
 733         iph->tos      = 0xc0;
 734         iph->frag_off = htons(IP_DF);
 735         iph->ttl      = 1;
 736         iph->daddr    = dst;
 737         iph->saddr    = fl4.saddr;
 738         iph->protocol = IPPROTO_IGMP;
 739         ip_select_ident(net, skb, NULL);
 740         ((u8 *)&iph[1])[0] = IPOPT_RA;
 741         ((u8 *)&iph[1])[1] = 4;
 742         ((u8 *)&iph[1])[2] = 0;
 743         ((u8 *)&iph[1])[3] = 0;
 744
 745         ih = skb_put(skb, sizeof(struct igmphdr));
 746         ih->type = type;
 747         ih->code = 0;
 748         ih->csum = 0;
 749         ih->group = group;
 750         ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 751
 752         return ip_local_out(net, skb->sk, skb);
 753 }
 754
 755 static void igmp_gq_timer_expire(unsigned long data)
 756 {
 757         struct in_device *in_dev = (struct in_device *)data;
 758
 759         in_dev->mr_gq_running = 0;
 760         igmpv3_send_report(in_dev, NULL);
 761         in_dev_put(in_dev);
 762 }
 763
 764 static void igmp_ifc_timer_expire(unsigned long data)
 765 {
 766         struct in_device *in_dev = (struct in_device *)data;
 767
 768         igmpv3_send_cr(in_dev);
 769         if (in_dev->mr_ifc_count) {
 770                 in_dev->mr_ifc_count--;
 771                 igmp_ifc_start_timer(in_dev,
 772                                      unsolicited_report_interval(in_dev));
 773         }
 774         in_dev_put(in_dev);
 775 }
 776
 777 static void igmp_ifc_event(struct in_device *in_dev)
 778 {
 779         struct net *net = dev_net(in_dev->dev);
 780         if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 781                 return;
 782         in_dev->mr_ifc_count = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
 783         igmp_ifc_start_timer(in_dev, 1);
 784 }
 785
 786
 787 static void igmp_timer_expire(unsigned long data)
 788 {
 789         struct ip_mc_list *im = (struct ip_mc_list *)data;
 790         struct in_device *in_dev = im->interface;
 791
 792         spin_lock(&im->lock);
 793         im->tm_running = 0;
 794
 795         if (im->unsolicit_count) {
 796                 im->unsolicit_count--;
 797                 igmp_start_timer(im, unsolicited_report_interval(in_dev));
 798         }
 799         im->reporter = 1;
 800         spin_unlock(&im->lock);
 801
 802         if (IGMP_V1_SEEN(in_dev))
 803                 igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
 804         else if (IGMP_V2_SEEN(in_dev))
 805                 igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
 806         else
 807                 igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
 808
 809         ip_ma_put(im);
 810 }
 811
 812 /* mark EXCLUDE-mode sources */
 813 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 814 {
 815         struct ip_sf_list *psf;
 816         int i, scount;
 817
 818         scount = 0;
 819         for (psf = pmc->sources; psf; psf = psf->sf_next) {
 820                 if (scount == nsrcs)
 821                         break;
 822                 for (i = 0; i < nsrcs; i++) {
 823                         /* skip inactive filters */
 824                         if (psf->sf_count[MCAST_INCLUDE] ||
 825                             pmc->sfcount[MCAST_EXCLUDE] !=
 826                             psf->sf_count[MCAST_EXCLUDE])
 827                                 break;
 828                         if (srcs[i] == psf->sf_inaddr) {
 829                                 scount++;
 830                                 break;
 831                         }
 832                 }
 833         }
 834         pmc->gsquery = 0;
 835         if (scount == nsrcs)    /* all sources excluded */
 836                 return 0;
 837         return 1;
 838 }
 839
 840 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 841 {
 842         struct ip_sf_list *psf;
 843         int i, scount;
 844
 845         if (pmc->sfmode == MCAST_EXCLUDE)
 846                 return igmp_xmarksources(pmc, nsrcs, srcs);
 847
 848         /* mark INCLUDE-mode sources */
 849         scount = 0;
 850         for (psf = pmc->sources; psf; psf = psf->sf_next) {
 851                 if (scount == nsrcs)
 852                         break;
 853                 for (i = 0; i < nsrcs; i++)
 854                         if (srcs[i] == psf->sf_inaddr) {
 855                                 psf->sf_gsresp = 1;
 856                                 scount++;
 857                                 break;
 858                         }
 859         }
 860         if (!scount) {
 861                 pmc->gsquery = 0;
 862                 return 0;
 863         }
 864         pmc->gsquery = 1;
 865         return 1;
 866 }
 867
 868 /* return true if packet was dropped */
 869 static bool igmp_heard_report(struct in_device *in_dev, __be32 group)
 870 {
 871         struct ip_mc_list *im;
 872         struct net *net = dev_net(in_dev->dev);
 873
 874         /* Timers are only set for non-local groups */
 875
 876         if (group == IGMP_ALL_HOSTS)
 877                 return false;
 878         if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
 879                 return false;
 880
 881         rcu_read_lock();
 882         for_each_pmc_rcu(in_dev, im) {
 883                 if (im->multiaddr == group) {
 884                         igmp_stop_timer(im);
 885                         break;
 886                 }
 887         }
 888         rcu_read_unlock();
 889         return false;
 890 }
 891
 892 /* return true if packet was dropped */
 893 static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
 894         int len)
 895 {
 896         struct igmphdr          *ih = igmp_hdr(skb);
 897         struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
 898         struct ip_mc_list       *im;
 899         __be32                  group = ih->group;
 900         int                     max_delay;
 901         int                     mark = 0;
 902         struct net              *net = dev_net(in_dev->dev);
 903
 904
 905         if (len == 8) {
 906                 if (ih->code == 0) {
 907                         /* Alas, old v1 router presents here. */
 908
 909                         max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 910                         in_dev->mr_v1_seen = jiffies +
 911                                 IGMP_V1_ROUTER_PRESENT_TIMEOUT;
 912                         group = 0;
 913                 } else {
 914                         /* v2 router present */
 915                         max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
 916                         in_dev->mr_v2_seen = jiffies +
 917                                 IGMP_V2_ROUTER_PRESENT_TIMEOUT;
 918                 }
 919                 /* cancel the interface change timer */
 920                 in_dev->mr_ifc_count = 0;
 921                 if (del_timer(&in_dev->mr_ifc_timer))
 922                         __in_dev_put(in_dev);
 923                 /* clear deleted report items */
 924                 igmpv3_clear_delrec(in_dev);
 925         } else if (len < 12) {
 926                 return true;    /* ignore bogus packet; freed by caller */
 927         } else if (IGMP_V1_SEEN(in_dev)) {
 928                 /* This is a v3 query with v1 queriers present */
 929                 max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 930                 group = 0;
 931         } else if (IGMP_V2_SEEN(in_dev)) {
 932                 /* this is a v3 query with v2 queriers present;
 933                  * Interpretation of the max_delay code is problematic here.
 934                  * A real v2 host would use ih_code directly, while v3 has a
 935                  * different encoding. We use the v3 encoding as more likely
 936                  * to be intended in a v3 query.
 937                  */
 938                 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 939                 if (!max_delay)
 940                         max_delay = 1;  /* can't mod w/ 0 */
 941         } else { /* v3 */
 942                 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
 943                         return true;
 944
 945                 ih3 = igmpv3_query_hdr(skb);
 946                 if (ih3->nsrcs) {
 947                         if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
 948                                            + ntohs(ih3->nsrcs)*sizeof(__be32)))
 949                                 return true;
 950                         ih3 = igmpv3_query_hdr(skb);
 951                 }
 952
 953                 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 954                 if (!max_delay)
 955                         max_delay = 1;  /* can't mod w/ 0 */
 956                 in_dev->mr_maxdelay = max_delay;
 957                 if (ih3->qrv)
 958                         in_dev->mr_qrv = ih3->qrv;
 959                 if (!group) { /* general query */
 960                         if (ih3->nsrcs)
 961                                 return true;    /* no sources allowed */
 962                         igmp_gq_start_timer(in_dev);
 963                         return false;
 964                 }
 965                 /* mark sources to include, if group & source-specific */
 966                 mark = ih3->nsrcs != 0;
 967         }
 968
 969         /*
 970          * - Start the timers in all of our membership records
 971          *   that the query applies to for the interface on
 972          *   which the query arrived excl. those that belong
 973          *   to a "local" group (224.0.0.X)
 974          * - For timers already running check if they need to
 975          *   be reset.
 976          * - Use the igmp->igmp_code field as the maximum
 977          *   delay possible
 978          */
 979         rcu_read_lock();
 980         for_each_pmc_rcu(in_dev, im) {
 981                 int changed;
 982
 983                 if (group && group != im->multiaddr)
 984                         continue;
 985                 if (im->multiaddr == IGMP_ALL_HOSTS)
 986                         continue;
 987                 if (ipv4_is_local_multicast(im->multiaddr) &&
 988                     !net->ipv4.sysctl_igmp_llm_reports)
 989                         continue;
 990                 spin_lock_bh(&im->lock);
 991                 if (im->tm_running)
 992                         im->gsquery = im->gsquery && mark;
 993                 else
 994                         im->gsquery = mark;
 995                 changed = !im->gsquery ||
 996                         igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
 997                 spin_unlock_bh(&im->lock);
 998                 if (changed)
 999                         igmp_mod_timer(im, max_delay);
1000         }
1001         rcu_read_unlock();
1002         return false;
1003 }
1004
1005 /* called in rcu_read_lock() section */
1006 int igmp_rcv(struct sk_buff *skb)
1007 {
1008         /* This basically follows the spec line by line -- see RFC1112 */
1009         struct igmphdr *ih;
1010         struct net_device *dev = skb->dev;
1011         struct in_device *in_dev;
1012         int len = skb->len;
1013         bool dropped = true;
1014
1015         if (netif_is_l3_master(dev)) {
1016                 dev = dev_get_by_index_rcu(dev_net(dev), IPCB(skb)->iif);
1017                 if (!dev)
1018                         goto drop;
1019         }
1020
1021         in_dev = __in_dev_get_rcu(dev);
1022         if (!in_dev)
1023                 goto drop;
1024
1025         if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
1026                 goto drop;
1027
1028         if (skb_checksum_simple_validate(skb))
1029                 goto drop;
1030
1031         ih = igmp_hdr(skb);
1032         switch (ih->type) {
1033         case IGMP_HOST_MEMBERSHIP_QUERY:
1034                 dropped = igmp_heard_query(in_dev, skb, len);
1035                 break;
1036         case IGMP_HOST_MEMBERSHIP_REPORT:
1037         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1038                 /* Is it our report looped back? */
1039                 if (rt_is_output_route(skb_rtable(skb)))
1040                         break;
1041                 /* don't rely on MC router hearing unicast reports */
1042                 if (skb->pkt_type == PACKET_MULTICAST ||
1043                     skb->pkt_type == PACKET_BROADCAST)
1044                         dropped = igmp_heard_report(in_dev, ih->group);
1045                 break;
1046         case IGMP_PIM:
1047 #ifdef CONFIG_IP_PIMSM_V1
1048                 return pim_rcv_v1(skb);
1049 #endif
1050         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1051         case IGMP_DVMRP:
1052         case IGMP_TRACE:
1053         case IGMP_HOST_LEAVE_MESSAGE:
1054         case IGMP_MTRACE:
1055         case IGMP_MTRACE_RESP:
1056                 break;
1057         default:
1058                 break;
1059         }
1060
1061 drop:
1062         if (dropped)
1063                 kfree_skb(skb);
1064         else
1065                 consume_skb(skb);
1066         return 0;
1067 }
1068
1069 #endif
1070
1071
1072 /*
1073  *      Add a filter to a device
1074  */
1075
1076 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1077 {
1078         char buf[MAX_ADDR_LEN];
1079         struct net_device *dev = in_dev->dev;
1080
1081         /* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1082            We will get multicast token leakage, when IFF_MULTICAST
1083            is changed. This check should be done in ndo_set_rx_mode
1084            routine. Something sort of:
1085            if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1086            --ANK
1087            */
1088         if (arp_mc_map(addr, buf, dev, 0) == 0)
1089                 dev_mc_add(dev, buf);
1090 }
1091
1092 /*
1093  *      Remove a filter from a device
1094  */
1095
1096 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1097 {
1098         char buf[MAX_ADDR_LEN];
1099         struct net_device *dev = in_dev->dev;
1100
1101         if (arp_mc_map(addr, buf, dev, 0) == 0)
1102                 dev_mc_del(dev, buf);
1103 }
1104
1105 #ifdef CONFIG_IP_MULTICAST
1106 /*
1107  * deleted ip_mc_list manipulation
1108  */
1109 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1110 {
1111         struct ip_mc_list *pmc;
1112         struct net *net = dev_net(in_dev->dev);
1113
1114         /* this is an "ip_mc_list" for convenience; only the fields below
1115          * are actually used. In particular, the refcnt and users are not
1116          * used for management of the delete list. Using the same structure
1117          * for deleted items allows change reports to use common code with
1118          * non-deleted or query-response MCA's.
1119          */
1120         pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
1121         if (!pmc)
1122                 return;
1123         spin_lock_init(&pmc->lock);
1124         spin_lock_bh(&im->lock);
1125         pmc->interface = im->interface;
1126         in_dev_hold(in_dev);
1127         pmc->multiaddr = im->multiaddr;
1128         pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1129         pmc->sfmode = im->sfmode;
1130         if (pmc->sfmode == MCAST_INCLUDE) {
1131                 struct ip_sf_list *psf;
1132
1133                 pmc->tomb = im->tomb;
1134                 pmc->sources = im->sources;
1135                 im->tomb = im->sources = NULL;
1136                 for (psf = pmc->sources; psf; psf = psf->sf_next)
1137                         psf->sf_crcount = pmc->crcount;
1138         }
1139         spin_unlock_bh(&im->lock);
1140
1141         spin_lock_bh(&in_dev->mc_tomb_lock);
1142         pmc->next = in_dev->mc_tomb;
1143         in_dev->mc_tomb = pmc;
1144         spin_unlock_bh(&in_dev->mc_tomb_lock);
1145 }
1146
1147 /*
1148  * restore ip_mc_list deleted records
1149  */
1150 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1151 {
1152         struct ip_mc_list *pmc, *pmc_prev;
1153         struct ip_sf_list *psf;
1154         struct net *net = dev_net(in_dev->dev);
1155         __be32 multiaddr = im->multiaddr;
1156
1157         spin_lock_bh(&in_dev->mc_tomb_lock);
1158         pmc_prev = NULL;
1159         for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) {
1160                 if (pmc->multiaddr == multiaddr)
1161                         break;
1162                 pmc_prev = pmc;
1163         }
1164         if (pmc) {
1165                 if (pmc_prev)
1166                         pmc_prev->next = pmc->next;
1167                 else
1168                         in_dev->mc_tomb = pmc->next;
1169         }
1170         spin_unlock_bh(&in_dev->mc_tomb_lock);
1171
1172         spin_lock_bh(&im->lock);
1173         if (pmc) {
1174                 im->interface = pmc->interface;
1175                 im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1176                 im->sfmode = pmc->sfmode;
1177                 if (pmc->sfmode == MCAST_INCLUDE) {
1178                         im->tomb = pmc->tomb;
1179                         im->sources = pmc->sources;
1180                         for (psf = im->sources; psf; psf = psf->sf_next)
1181                                 psf->sf_crcount = im->crcount;
1182                 }
1183                 in_dev_put(pmc->interface);
1184                 kfree(pmc);
1185         }
1186         spin_unlock_bh(&im->lock);
1187 }
1188
1189 /*
1190  * flush ip_mc_list deleted records
1191  */
1192 static void igmpv3_clear_delrec(struct in_device *in_dev)
1193 {
1194         struct ip_mc_list *pmc, *nextpmc;
1195
1196         spin_lock_bh(&in_dev->mc_tomb_lock);
1197         pmc = in_dev->mc_tomb;
1198         in_dev->mc_tomb = NULL;
1199         spin_unlock_bh(&in_dev->mc_tomb_lock);
1200
1201         for (; pmc; pmc = nextpmc) {
1202                 nextpmc = pmc->next;
1203                 ip_mc_clear_src(pmc);
1204                 in_dev_put(pmc->interface);
1205                 kfree(pmc);
1206         }
1207         /* clear dead sources, too */
1208         rcu_read_lock();
1209         for_each_pmc_rcu(in_dev, pmc) {
1210                 struct ip_sf_list *psf, *psf_next;
1211
1212                 spin_lock_bh(&pmc->lock);
1213                 psf = pmc->tomb;
1214                 pmc->tomb = NULL;
1215                 spin_unlock_bh(&pmc->lock);
1216                 for (; psf; psf = psf_next) {
1217                         psf_next = psf->sf_next;
1218                         kfree(psf);
1219                 }
1220         }
1221         rcu_read_unlock();
1222 }
1223 #endif
1224
1225 static void igmp_group_dropped(struct ip_mc_list *im)
1226 {
1227         struct in_device *in_dev = im->interface;
1228 #ifdef CONFIG_IP_MULTICAST
1229         struct net *net = dev_net(in_dev->dev);
1230         int reporter;
1231 #endif
1232
1233         if (im->loaded) {
1234                 im->loaded = 0;
1235                 ip_mc_filter_del(in_dev, im->multiaddr);
1236         }
1237
1238 #ifdef CONFIG_IP_MULTICAST
1239         if (im->multiaddr == IGMP_ALL_HOSTS)
1240                 return;
1241         if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1242                 return;
1243
1244         reporter = im->reporter;
1245         igmp_stop_timer(im);
1246
1247         if (!in_dev->dead) {
1248                 if (IGMP_V1_SEEN(in_dev))
1249                         return;
1250                 if (IGMP_V2_SEEN(in_dev)) {
1251                         if (reporter)
1252                                 igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1253                         return;
1254                 }
1255                 /* IGMPv3 */
1256                 igmpv3_add_delrec(in_dev, im);
1257
1258                 igmp_ifc_event(in_dev);
1259         }
1260 #endif
1261 }
1262
1263 static void igmp_group_added(struct ip_mc_list *im)
1264 {
1265         struct in_device *in_dev = im->interface;
1266 #ifdef CONFIG_IP_MULTICAST
1267         struct net *net = dev_net(in_dev->dev);
1268 #endif
1269
1270         if (im->loaded == 0) {
1271                 im->loaded = 1;
1272                 ip_mc_filter_add(in_dev, im->multiaddr);
1273         }
1274
1275 #ifdef CONFIG_IP_MULTICAST
1276         if (im->multiaddr == IGMP_ALL_HOSTS)
1277                 return;
1278         if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1279                 return;
1280
1281         if (in_dev->dead)
1282                 return;
1283         if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1284                 spin_lock_bh(&im->lock);
1285                 igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY);
1286                 spin_unlock_bh(&im->lock);
1287                 return;
1288         }
1289         /* else, v3 */
1290
1291         im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1292         igmp_ifc_event(in_dev);
1293 #endif
1294 }
1295
1296
1297 /*
1298  *      Multicast list managers
1299  */
1300
1301 static u32 ip_mc_hash(const struct ip_mc_list *im)
1302 {
1303         return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
1304 }
1305
1306 static void ip_mc_hash_add(struct in_device *in_dev,
1307                            struct ip_mc_list *im)
1308 {
1309         struct ip_mc_list __rcu **mc_hash;
1310         u32 hash;
1311
1312         mc_hash = rtnl_dereference(in_dev->mc_hash);
1313         if (mc_hash) {
1314                 hash = ip_mc_hash(im);
1315                 im->next_hash = mc_hash[hash];
1316                 rcu_assign_pointer(mc_hash[hash], im);
1317                 return;
1318         }
1319
1320         /* do not use a hash table for small number of items */
1321         if (in_dev->mc_count < 4)
1322                 return;
1323
1324         mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
1325                           GFP_KERNEL);
1326         if (!mc_hash)
1327                 return;
1328
1329         for_each_pmc_rtnl(in_dev, im) {
1330                 hash = ip_mc_hash(im);
1331                 im->next_hash = mc_hash[hash];
1332                 RCU_INIT_POINTER(mc_hash[hash], im);
1333         }
1334
1335         rcu_assign_pointer(in_dev->mc_hash, mc_hash);
1336 }
1337
1338 static void ip_mc_hash_remove(struct in_device *in_dev,
1339                               struct ip_mc_list *im)
1340 {
1341         struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
1342         struct ip_mc_list *aux;
1343
1344         if (!mc_hash)
1345                 return;
1346         mc_hash += ip_mc_hash(im);
1347         while ((aux = rtnl_dereference(*mc_hash)) != im)
1348                 mc_hash = &aux->next_hash;
1349         *mc_hash = im->next_hash;
1350 }
1351
1352
1353 /*
1354  *      A socket has joined a multicast group on device dev.
1355  */
1356
1357 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1358 {
1359         struct ip_mc_list *im;
1360 #ifdef CONFIG_IP_MULTICAST
1361         struct net *net = dev_net(in_dev->dev);
1362 #endif
1363
1364         ASSERT_RTNL();
1365
1366         for_each_pmc_rtnl(in_dev, im) {
1367                 if (im->multiaddr == addr) {
1368                         im->users++;
1369                         ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1370                         goto out;
1371                 }
1372         }
1373
1374         im = kzalloc(sizeof(*im), GFP_KERNEL);
1375         if (!im)
1376                 goto out;
1377
1378         im->users = 1;
1379         im->interface = in_dev;
1380         in_dev_hold(in_dev);
1381         im->multiaddr = addr;
1382         /* initial mode is (EX, empty) */
1383         im->sfmode = MCAST_EXCLUDE;
1384         im->sfcount[MCAST_EXCLUDE] = 1;
1385         refcount_set(&im->refcnt, 1);
1386         spin_lock_init(&im->lock);
1387 #ifdef CONFIG_IP_MULTICAST
1388         setup_timer(&im->timer, igmp_timer_expire, (unsigned long)im);
1389         im->unsolicit_count = net->ipv4.sysctl_igmp_qrv;
1390 #endif
1391
1392         im->next_rcu = in_dev->mc_list;
1393         in_dev->mc_count++;
1394         rcu_assign_pointer(in_dev->mc_list, im);
1395
1396         ip_mc_hash_add(in_dev, im);
1397
1398 #ifdef CONFIG_IP_MULTICAST
1399         igmpv3_del_delrec(in_dev, im);
1400 #endif
1401         igmp_group_added(im);
1402         if (!in_dev->dead)
1403                 ip_rt_multicast_event(in_dev);
1404 out:
1405         return;
1406 }
1407 EXPORT_SYMBOL(ip_mc_inc_group);
1408
1409 static int ip_mc_check_iphdr(struct sk_buff *skb)
1410 {
1411         const struct iphdr *iph;
1412         unsigned int len;
1413         unsigned int offset = skb_network_offset(skb) + sizeof(*iph);
1414
1415         if (!pskb_may_pull(skb, offset))
1416                 return -EINVAL;
1417
1418         iph = ip_hdr(skb);
1419
1420         if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph))
1421                 return -EINVAL;
1422
1423         offset += ip_hdrlen(skb) - sizeof(*iph);
1424
1425         if (!pskb_may_pull(skb, offset))
1426                 return -EINVAL;
1427
1428         iph = ip_hdr(skb);
1429
1430         if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1431                 return -EINVAL;
1432
1433         len = skb_network_offset(skb) + ntohs(iph->tot_len);
1434         if (skb->len < len || len < offset)
1435                 return -EINVAL;
1436
1437         skb_set_transport_header(skb, offset);
1438
1439         return 0;
1440 }
1441
1442 static int ip_mc_check_igmp_reportv3(struct sk_buff *skb)
1443 {
1444         unsigned int len = skb_transport_offset(skb);
1445
1446         len += sizeof(struct igmpv3_report);
1447
1448         return pskb_may_pull(skb, len) ? 0 : -EINVAL;
1449 }
1450
1451 static int ip_mc_check_igmp_query(struct sk_buff *skb)
1452 {
1453         unsigned int len = skb_transport_offset(skb);
1454
1455         len += sizeof(struct igmphdr);
1456         if (skb->len < len)
1457                 return -EINVAL;
1458
1459         /* IGMPv{1,2}? */
1460         if (skb->len != len) {
1461                 /* or IGMPv3? */
1462                 len += sizeof(struct igmpv3_query) - sizeof(struct igmphdr);
1463                 if (skb->len < len || !pskb_may_pull(skb, len))
1464                         return -EINVAL;
1465         }
1466
1467         /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1468          * all-systems destination addresses (224.0.0.1) for general queries
1469          */
1470         if (!igmp_hdr(skb)->group &&
1471             ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP))
1472                 return -EINVAL;
1473
1474         return 0;
1475 }
1476
1477 static int ip_mc_check_igmp_msg(struct sk_buff *skb)
1478 {
1479         switch (igmp_hdr(skb)->type) {
1480         case IGMP_HOST_LEAVE_MESSAGE:
1481         case IGMP_HOST_MEMBERSHIP_REPORT:
1482         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1483                 /* fall through */
1484                 return 0;
1485         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1486                 return ip_mc_check_igmp_reportv3(skb);
1487         case IGMP_HOST_MEMBERSHIP_QUERY:
1488                 return ip_mc_check_igmp_query(skb);
1489         default:
1490                 return -ENOMSG;
1491         }
1492 }
1493
1494 static inline __sum16 ip_mc_validate_checksum(struct sk_buff *skb)
1495 {
1496         return skb_checksum_simple_validate(skb);
1497 }
1498
1499 static int __ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
1500
1501 {
1502         struct sk_buff *skb_chk;
1503         unsigned int transport_len;
1504         unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr);
1505         int ret = -EINVAL;
1506
1507         transport_len = ntohs(ip_hdr(skb)->tot_len) - ip_hdrlen(skb);
1508
1509         skb_chk = skb_checksum_trimmed(skb, transport_len,
1510                                        ip_mc_validate_checksum);
1511         if (!skb_chk)
1512                 goto err;
1513
1514         if (!pskb_may_pull(skb_chk, len))
1515                 goto err;
1516
1517         ret = ip_mc_check_igmp_msg(skb_chk);
1518         if (ret)
1519                 goto err;
1520
1521         if (skb_trimmed)
1522                 *skb_trimmed = skb_chk;
1523         /* free now unneeded clone */
1524         else if (skb_chk != skb)
1525                 kfree_skb(skb_chk);
1526
1527         ret = 0;
1528
1529 err:
1530         if (ret && skb_chk && skb_chk != skb)
1531                 kfree_skb(skb_chk);
1532
1533         return ret;
1534 }
1535
1536 /**
1537  * ip_mc_check_igmp - checks whether this is a sane IGMP packet
1538  * @skb: the skb to validate
1539  * @skb_trimmed: to store an skb pointer trimmed to IPv4 packet tail (optional)
1540  *
1541  * Checks whether an IPv4 packet is a valid IGMP packet. If so sets
1542  * skb transport header accordingly and returns zero.
1543  *
1544  * -EINVAL: A broken packet was detected, i.e. it violates some internet
1545  *  standard
1546  * -ENOMSG: IP header validation succeeded but it is not an IGMP packet.
1547  * -ENOMEM: A memory allocation failure happened.
1548  *
1549  * Optionally, an skb pointer might be provided via skb_trimmed (or set it
1550  * to NULL): After parsing an IGMP packet successfully it will point to
1551  * an skb which has its tail aligned to the IP packet end. This might
1552  * either be the originally provided skb or a trimmed, cloned version if
1553  * the skb frame had data beyond the IP packet. A cloned skb allows us
1554  * to leave the original skb and its full frame unchanged (which might be
1555  * desirable for layer 2 frame jugglers).
1556  *
1557  * Caller needs to set the skb network header and free any returned skb if it
1558  * differs from the provided skb.
1559  */
1560 int ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
1561 {
1562         int ret = ip_mc_check_iphdr(skb);
1563
1564         if (ret < 0)
1565                 return ret;
1566
1567         if (ip_hdr(skb)->protocol != IPPROTO_IGMP)
1568                 return -ENOMSG;
1569
1570         return __ip_mc_check_igmp(skb, skb_trimmed);
1571 }
1572 EXPORT_SYMBOL(ip_mc_check_igmp);
1573
1574 /*
1575  *      Resend IGMP JOIN report; used by netdev notifier.
1576  */
1577 static void ip_mc_rejoin_groups(struct in_device *in_dev)
1578 {
1579 #ifdef CONFIG_IP_MULTICAST
1580         struct ip_mc_list *im;
1581         int type;
1582         struct net *net = dev_net(in_dev->dev);
1583
1584         ASSERT_RTNL();
1585
1586         for_each_pmc_rtnl(in_dev, im) {
1587                 if (im->multiaddr == IGMP_ALL_HOSTS)
1588                         continue;
1589                 if (ipv4_is_local_multicast(im->multiaddr) &&
1590                     !net->ipv4.sysctl_igmp_llm_reports)
1591                         continue;
1592
1593                 /* a failover is happening and switches
1594                  * must be notified immediately
1595                  */
1596                 if (IGMP_V1_SEEN(in_dev))
1597                         type = IGMP_HOST_MEMBERSHIP_REPORT;
1598                 else if (IGMP_V2_SEEN(in_dev))
1599                         type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1600                 else
1601                         type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1602                 igmp_send_report(in_dev, im, type);
1603         }
1604 #endif
1605 }
1606
1607 /*
1608  *      A socket has left a multicast group on device dev
1609  */
1610
1611 void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
1612 {
1613         struct ip_mc_list *i;
1614         struct ip_mc_list __rcu **ip;
1615
1616         ASSERT_RTNL();
1617
1618         for (ip = &in_dev->mc_list;
1619              (i = rtnl_dereference(*ip)) != NULL;
1620              ip = &i->next_rcu) {
1621                 if (i->multiaddr == addr) {
1622                         if (--i->users == 0) {
1623                                 ip_mc_hash_remove(in_dev, i);
1624                                 *ip = i->next_rcu;
1625                                 in_dev->mc_count--;
1626                                 igmp_group_dropped(i);
1627                                 ip_mc_clear_src(i);
1628
1629                                 if (!in_dev->dead)
1630                                         ip_rt_multicast_event(in_dev);
1631
1632                                 ip_ma_put(i);
1633                                 return;
1634                         }
1635                         break;
1636                 }
1637         }
1638 }
1639 EXPORT_SYMBOL(ip_mc_dec_group);
1640
1641 /* Device changing type */
1642
1643 void ip_mc_unmap(struct in_device *in_dev)
1644 {
1645         struct ip_mc_list *pmc;
1646
1647         ASSERT_RTNL();
1648
1649         for_each_pmc_rtnl(in_dev, pmc)
1650                 igmp_group_dropped(pmc);
1651 }
1652
1653 void ip_mc_remap(struct in_device *in_dev)
1654 {
1655         struct ip_mc_list *pmc;
1656
1657         ASSERT_RTNL();
1658
1659         for_each_pmc_rtnl(in_dev, pmc) {
1660 #ifdef CONFIG_IP_MULTICAST
1661                 igmpv3_del_delrec(in_dev, pmc);
1662 #endif
1663                 igmp_group_added(pmc);
1664         }
1665 }
1666
1667 /* Device going down */
1668
1669 void ip_mc_down(struct in_device *in_dev)
1670 {
1671         struct ip_mc_list *pmc;
1672
1673         ASSERT_RTNL();
1674
1675         for_each_pmc_rtnl(in_dev, pmc)
1676                 igmp_group_dropped(pmc);
1677
1678 #ifdef CONFIG_IP_MULTICAST
1679         in_dev->mr_ifc_count = 0;
1680         if (del_timer(&in_dev->mr_ifc_timer))
1681                 __in_dev_put(in_dev);
1682         in_dev->mr_gq_running = 0;
1683         if (del_timer(&in_dev->mr_gq_timer))
1684                 __in_dev_put(in_dev);
1685 #endif
1686
1687         ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1688 }
1689
1690 void ip_mc_init_dev(struct in_device *in_dev)
1691 {
1692 #ifdef CONFIG_IP_MULTICAST
1693         struct net *net = dev_net(in_dev->dev);
1694 #endif
1695         ASSERT_RTNL();
1696
1697 #ifdef CONFIG_IP_MULTICAST
1698         setup_timer(&in_dev->mr_gq_timer, igmp_gq_timer_expire,
1699                         (unsigned long)in_dev);
1700         setup_timer(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire,
1701                         (unsigned long)in_dev);
1702         in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1703 #endif
1704
1705         spin_lock_init(&in_dev->mc_tomb_lock);
1706 }
1707
1708 /* Device going up */
1709
1710 void ip_mc_up(struct in_device *in_dev)
1711 {
1712         struct ip_mc_list *pmc;
1713 #ifdef CONFIG_IP_MULTICAST
1714         struct net *net = dev_net(in_dev->dev);
1715 #endif
1716
1717         ASSERT_RTNL();
1718
1719 #ifdef CONFIG_IP_MULTICAST
1720         in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1721 #endif
1722         ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1723
1724         for_each_pmc_rtnl(in_dev, pmc) {
1725 #ifdef CONFIG_IP_MULTICAST
1726                 igmpv3_del_delrec(in_dev, pmc);
1727 #endif
1728                 igmp_group_added(pmc);
1729         }
1730 }
1731
1732 /*
1733  *      Device is about to be destroyed: clean up.
1734  */
1735
1736 void ip_mc_destroy_dev(struct in_device *in_dev)
1737 {
1738         struct ip_mc_list *i;
1739
1740         ASSERT_RTNL();
1741
1742         /* Deactivate timers */
1743         ip_mc_down(in_dev);
1744 #ifdef CONFIG_IP_MULTICAST
1745         igmpv3_clear_delrec(in_dev);
1746 #endif
1747
1748         while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1749                 in_dev->mc_list = i->next_rcu;
1750                 in_dev->mc_count--;
1751                 ip_ma_put(i);
1752         }
1753 }
1754
1755 /* RTNL is locked */
1756 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1757 {
1758         struct net_device *dev = NULL;
1759         struct in_device *idev = NULL;
1760
1761         if (imr->imr_ifindex) {
1762                 idev = inetdev_by_index(net, imr->imr_ifindex);
1763                 return idev;
1764         }
1765         if (imr->imr_address.s_addr) {
1766                 dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1767                 if (!dev)
1768                         return NULL;
1769         }
1770
1771         if (!dev) {
1772                 struct rtable *rt = ip_route_output(net,
1773                                                     imr->imr_multiaddr.s_addr,
1774                                                     0, 0, 0);
1775                 if (!IS_ERR(rt)) {
1776                         dev = rt->dst.dev;
1777                         ip_rt_put(rt);
1778                 }
1779         }
1780         if (dev) {
1781                 imr->imr_ifindex = dev->ifindex;
1782                 idev = __in_dev_get_rtnl(dev);
1783         }
1784         return idev;
1785 }
1786
1787 /*
1788  *      Join a socket to a group
1789  */
1790
1791 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1792         __be32 *psfsrc)
1793 {
1794         struct ip_sf_list *psf, *psf_prev;
1795         int rv = 0;
1796
1797         psf_prev = NULL;
1798         for (psf = pmc->sources; psf; psf = psf->sf_next) {
1799                 if (psf->sf_inaddr == *psfsrc)
1800                         break;
1801                 psf_prev = psf;
1802         }
1803         if (!psf || psf->sf_count[sfmode] == 0) {
1804                 /* source filter not found, or count wrong =>  bug */
1805                 return -ESRCH;
1806         }
1807         psf->sf_count[sfmode]--;
1808         if (psf->sf_count[sfmode] == 0) {
1809                 ip_rt_multicast_event(pmc->interface);
1810         }
1811         if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1812 #ifdef CONFIG_IP_MULTICAST
1813                 struct in_device *in_dev = pmc->interface;
1814                 struct net *net = dev_net(in_dev->dev);
1815 #endif
1816
1817                 /* no more filters for this source */
1818                 if (psf_prev)
1819                         psf_prev->sf_next = psf->sf_next;
1820                 else
1821                         pmc->sources = psf->sf_next;
1822 #ifdef CONFIG_IP_MULTICAST
1823                 if (psf->sf_oldin &&
1824                     !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1825                         psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1826                         psf->sf_next = pmc->tomb;
1827                         pmc->tomb = psf;
1828                         rv = 1;
1829                 } else
1830 #endif
1831                         kfree(psf);
1832         }
1833         return rv;
1834 }
1835
1836 #ifndef CONFIG_IP_MULTICAST
1837 #define igmp_ifc_event(x)       do { } while (0)
1838 #endif
1839
1840 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1841                          int sfcount, __be32 *psfsrc, int delta)
1842 {
1843         struct ip_mc_list *pmc;
1844         int     changerec = 0;
1845         int     i, err;
1846
1847         if (!in_dev)
1848                 return -ENODEV;
1849         rcu_read_lock();
1850         for_each_pmc_rcu(in_dev, pmc) {
1851                 if (*pmca == pmc->multiaddr)
1852                         break;
1853         }
1854         if (!pmc) {
1855                 /* MCA not found?? bug */
1856                 rcu_read_unlock();
1857                 return -ESRCH;
1858         }
1859         spin_lock_bh(&pmc->lock);
1860         rcu_read_unlock();
1861 #ifdef CONFIG_IP_MULTICAST
1862         sf_markstate(pmc);
1863 #endif
1864         if (!delta) {
1865                 err = -EINVAL;
1866                 if (!pmc->sfcount[sfmode])
1867                         goto out_unlock;
1868                 pmc->sfcount[sfmode]--;
1869         }
1870         err = 0;
1871         for (i = 0; i < sfcount; i++) {
1872                 int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1873
1874                 changerec |= rv > 0;
1875                 if (!err && rv < 0)
1876                         err = rv;
1877         }
1878         if (pmc->sfmode == MCAST_EXCLUDE &&
1879             pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1880             pmc->sfcount[MCAST_INCLUDE]) {
1881 #ifdef CONFIG_IP_MULTICAST
1882                 struct ip_sf_list *psf;
1883                 struct net *net = dev_net(in_dev->dev);
1884 #endif
1885
1886                 /* filter mode change */
1887                 pmc->sfmode = MCAST_INCLUDE;
1888 #ifdef CONFIG_IP_MULTICAST
1889                 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1890                 in_dev->mr_ifc_count = pmc->crcount;
1891                 for (psf = pmc->sources; psf; psf = psf->sf_next)
1892                         psf->sf_crcount = 0;
1893                 igmp_ifc_event(pmc->interface);
1894         } else if (sf_setstate(pmc) || changerec) {
1895                 igmp_ifc_event(pmc->interface);
1896 #endif
1897         }
1898 out_unlock:
1899         spin_unlock_bh(&pmc->lock);
1900         return err;
1901 }
1902
1903 /*
1904  * Add multicast single-source filter to the interface list
1905  */
1906 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1907         __be32 *psfsrc)
1908 {
1909         struct ip_sf_list *psf, *psf_prev;
1910
1911         psf_prev = NULL;
1912         for (psf = pmc->sources; psf; psf = psf->sf_next) {
1913                 if (psf->sf_inaddr == *psfsrc)
1914                         break;
1915                 psf_prev = psf;
1916         }
1917         if (!psf) {
1918                 psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1919                 if (!psf)
1920                         return -ENOBUFS;
1921                 psf->sf_inaddr = *psfsrc;
1922                 if (psf_prev) {
1923                         psf_prev->sf_next = psf;
1924                 } else
1925                         pmc->sources = psf;
1926         }
1927         psf->sf_count[sfmode]++;
1928         if (psf->sf_count[sfmode] == 1) {
1929                 ip_rt_multicast_event(pmc->interface);
1930         }
1931         return 0;
1932 }
1933
1934 #ifdef CONFIG_IP_MULTICAST
1935 static void sf_markstate(struct ip_mc_list *pmc)
1936 {
1937         struct ip_sf_list *psf;
1938         int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1939
1940         for (psf = pmc->sources; psf; psf = psf->sf_next)
1941                 if (pmc->sfcount[MCAST_EXCLUDE]) {
1942                         psf->sf_oldin = mca_xcount ==
1943                                 psf->sf_count[MCAST_EXCLUDE] &&
1944                                 !psf->sf_count[MCAST_INCLUDE];
1945                 } else
1946                         psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1947 }
1948
1949 static int sf_setstate(struct ip_mc_list *pmc)
1950 {
1951         struct ip_sf_list *psf, *dpsf;
1952         int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1953         int qrv = pmc->interface->mr_qrv;
1954         int new_in, rv;
1955
1956         rv = 0;
1957         for (psf = pmc->sources; psf; psf = psf->sf_next) {
1958                 if (pmc->sfcount[MCAST_EXCLUDE]) {
1959                         new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1960                                 !psf->sf_count[MCAST_INCLUDE];
1961                 } else
1962                         new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1963                 if (new_in) {
1964                         if (!psf->sf_oldin) {
1965                                 struct ip_sf_list *prev = NULL;
1966
1967                                 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) {
1968                                         if (dpsf->sf_inaddr == psf->sf_inaddr)
1969                                                 break;
1970                                         prev = dpsf;
1971                                 }
1972                                 if (dpsf) {
1973                                         if (prev)
1974                                                 prev->sf_next = dpsf->sf_next;
1975                                         else
1976                                                 pmc->tomb = dpsf->sf_next;
1977                                         kfree(dpsf);
1978                                 }
1979                                 psf->sf_crcount = qrv;
1980                                 rv++;
1981                         }
1982                 } else if (psf->sf_oldin) {
1983
1984                         psf->sf_crcount = 0;
1985                         /*
1986                          * add or update "delete" records if an active filter
1987                          * is now inactive
1988                          */
1989                         for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next)
1990                                 if (dpsf->sf_inaddr == psf->sf_inaddr)
1991                                         break;
1992                         if (!dpsf) {
1993                                 dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
1994                                 if (!dpsf)
1995                                         continue;
1996                                 *dpsf = *psf;
1997                                 /* pmc->lock held by callers */
1998                                 dpsf->sf_next = pmc->tomb;
1999                                 pmc->tomb = dpsf;
2000                         }
2001                         dpsf->sf_crcount = qrv;
2002                         rv++;
2003                 }
2004         }
2005         return rv;
2006 }
2007 #endif
2008
2009 /*
2010  * Add multicast source filter list to the interface list
2011  */
2012 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
2013                          int sfcount, __be32 *psfsrc, int delta)
2014 {
2015         struct ip_mc_list *pmc;
2016         int     isexclude;
2017         int     i, err;
2018
2019         if (!in_dev)
2020                 return -ENODEV;
2021         rcu_read_lock();
2022         for_each_pmc_rcu(in_dev, pmc) {
2023                 if (*pmca == pmc->multiaddr)
2024                         break;
2025         }
2026         if (!pmc) {
2027                 /* MCA not found?? bug */
2028                 rcu_read_unlock();
2029                 return -ESRCH;
2030         }
2031         spin_lock_bh(&pmc->lock);
2032         rcu_read_unlock();
2033
2034 #ifdef CONFIG_IP_MULTICAST
2035         sf_markstate(pmc);
2036 #endif
2037         isexclude = pmc->sfmode == MCAST_EXCLUDE;
2038         if (!delta)
2039                 pmc->sfcount[sfmode]++;
2040         err = 0;
2041         for (i = 0; i < sfcount; i++) {
2042                 err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2043                 if (err)
2044                         break;
2045         }
2046         if (err) {
2047                 int j;
2048
2049                 if (!delta)
2050                         pmc->sfcount[sfmode]--;
2051                 for (j = 0; j < i; j++)
2052                         (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2053         } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
2054 #ifdef CONFIG_IP_MULTICAST
2055                 struct ip_sf_list *psf;
2056                 struct net *net = dev_net(pmc->interface->dev);
2057                 in_dev = pmc->interface;
2058 #endif
2059
2060                 /* filter mode change */
2061                 if (pmc->sfcount[MCAST_EXCLUDE])
2062                         pmc->sfmode = MCAST_EXCLUDE;
2063                 else if (pmc->sfcount[MCAST_INCLUDE])
2064                         pmc->sfmode = MCAST_INCLUDE;
2065 #ifdef CONFIG_IP_MULTICAST
2066                 /* else no filters; keep old mode for reports */
2067
2068                 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
2069                 in_dev->mr_ifc_count = pmc->crcount;
2070                 for (psf = pmc->sources; psf; psf = psf->sf_next)
2071                         psf->sf_crcount = 0;
2072                 igmp_ifc_event(in_dev);
2073         } else if (sf_setstate(pmc)) {
2074                 igmp_ifc_event(in_dev);
2075 #endif
2076         }
2077         spin_unlock_bh(&pmc->lock);
2078         return err;
2079 }
2080
2081 static void ip_mc_clear_src(struct ip_mc_list *pmc)
2082 {
2083         struct ip_sf_list *psf, *nextpsf, *tomb, *sources;
2084
2085         spin_lock_bh(&pmc->lock);
2086         tomb = pmc->tomb;
2087         pmc->tomb = NULL;
2088         sources = pmc->sources;
2089         pmc->sources = NULL;
2090         pmc->sfmode = MCAST_EXCLUDE;
2091         pmc->sfcount[MCAST_INCLUDE] = 0;
2092         pmc->sfcount[MCAST_EXCLUDE] = 1;
2093         spin_unlock_bh(&pmc->lock);
2094
2095         for (psf = tomb; psf; psf = nextpsf) {
2096                 nextpsf = psf->sf_next;
2097                 kfree(psf);
2098         }
2099         for (psf = sources; psf; psf = nextpsf) {
2100                 nextpsf = psf->sf_next;
2101                 kfree(psf);
2102         }
2103 }
2104
2105 /* Join a multicast group
2106  */
2107
2108 int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
2109 {
2110         __be32 addr = imr->imr_multiaddr.s_addr;
2111         struct ip_mc_socklist *iml, *i;
2112         struct in_device *in_dev;
2113         struct inet_sock *inet = inet_sk(sk);
2114         struct net *net = sock_net(sk);
2115         int ifindex;
2116         int count = 0;
2117         int err;
2118
2119         ASSERT_RTNL();
2120
2121         if (!ipv4_is_multicast(addr))
2122                 return -EINVAL;
2123
2124         in_dev = ip_mc_find_dev(net, imr);
2125
2126         if (!in_dev) {
2127                 err = -ENODEV;
2128                 goto done;
2129         }
2130
2131         err = -EADDRINUSE;
2132         ifindex = imr->imr_ifindex;
2133         for_each_pmc_rtnl(inet, i) {
2134                 if (i->multi.imr_multiaddr.s_addr == addr &&
2135                     i->multi.imr_ifindex == ifindex)
2136                         goto done;
2137                 count++;
2138         }
2139         err = -ENOBUFS;
2140         if (count >= net->ipv4.sysctl_igmp_max_memberships)
2141                 goto done;
2142         iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
2143         if (!iml)
2144                 goto done;
2145
2146         memcpy(&iml->multi, imr, sizeof(*imr));
2147         iml->next_rcu = inet->mc_list;
2148         iml->sflist = NULL;
2149         iml->sfmode = MCAST_EXCLUDE;
2150         rcu_assign_pointer(inet->mc_list, iml);
2151         ip_mc_inc_group(in_dev, addr);
2152         err = 0;
2153 done:
2154         return err;
2155 }
2156 EXPORT_SYMBOL(ip_mc_join_group);
2157
2158 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
2159                            struct in_device *in_dev)
2160 {
2161         struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
2162         int err;
2163
2164         if (!psf) {
2165                 /* any-source empty exclude case */
2166                 return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2167                         iml->sfmode, 0, NULL, 0);
2168         }
2169         err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2170                         iml->sfmode, psf->sl_count, psf->sl_addr, 0);
2171         RCU_INIT_POINTER(iml->sflist, NULL);
2172         /* decrease mem now to avoid the memleak warning */
2173         atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc);
2174         kfree_rcu(psf, rcu);
2175         return err;
2176 }
2177
2178 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
2179 {
2180         struct inet_sock *inet = inet_sk(sk);
2181         struct ip_mc_socklist *iml;
2182         struct ip_mc_socklist __rcu **imlp;
2183         struct in_device *in_dev;
2184         struct net *net = sock_net(sk);
2185         __be32 group = imr->imr_multiaddr.s_addr;
2186         u32 ifindex;
2187         int ret = -EADDRNOTAVAIL;
2188
2189         ASSERT_RTNL();
2190
2191         in_dev = ip_mc_find_dev(net, imr);
2192         if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) {
2193                 ret = -ENODEV;
2194                 goto out;
2195         }
2196         ifindex = imr->imr_ifindex;
2197         for (imlp = &inet->mc_list;
2198              (iml = rtnl_dereference(*imlp)) != NULL;
2199              imlp = &iml->next_rcu) {
2200                 if (iml->multi.imr_multiaddr.s_addr != group)
2201                         continue;
2202                 if (ifindex) {
2203                         if (iml->multi.imr_ifindex != ifindex)
2204                                 continue;
2205                 } else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
2206                                 iml->multi.imr_address.s_addr)
2207                         continue;
2208
2209                 (void) ip_mc_leave_src(sk, iml, in_dev);
2210
2211                 *imlp = iml->next_rcu;
2212
2213                 if (in_dev)
2214                         ip_mc_dec_group(in_dev, group);
2215
2216                 /* decrease mem now to avoid the memleak warning */
2217                 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2218                 kfree_rcu(iml, rcu);
2219                 return 0;
2220         }
2221 out:
2222         return ret;
2223 }
2224 EXPORT_SYMBOL(ip_mc_leave_group);
2225
2226 int ip_mc_source(int add, int omode, struct sock *sk, struct
2227         ip_mreq_source *mreqs, int ifindex)
2228 {
2229         int err;
2230         struct ip_mreqn imr;
2231         __be32 addr = mreqs->imr_multiaddr;
2232         struct ip_mc_socklist *pmc;
2233         struct in_device *in_dev = NULL;
2234         struct inet_sock *inet = inet_sk(sk);
2235         struct ip_sf_socklist *psl;
2236         struct net *net = sock_net(sk);
2237         int leavegroup = 0;
2238         int i, j, rv;
2239
2240         if (!ipv4_is_multicast(addr))
2241                 return -EINVAL;
2242
2243         ASSERT_RTNL();
2244
2245         imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
2246         imr.imr_address.s_addr = mreqs->imr_interface;
2247         imr.imr_ifindex = ifindex;
2248         in_dev = ip_mc_find_dev(net, &imr);
2249
2250         if (!in_dev) {
2251                 err = -ENODEV;
2252                 goto done;
2253         }
2254         err = -EADDRNOTAVAIL;
2255
2256         for_each_pmc_rtnl(inet, pmc) {
2257                 if ((pmc->multi.imr_multiaddr.s_addr ==
2258                      imr.imr_multiaddr.s_addr) &&
2259                     (pmc->multi.imr_ifindex == imr.imr_ifindex))
2260                         break;
2261         }
2262         if (!pmc) {             /* must have a prior join */
2263                 err = -EINVAL;
2264                 goto done;
2265         }
2266         /* if a source filter was set, must be the same mode as before */
2267         if (pmc->sflist) {
2268                 if (pmc->sfmode != omode) {
2269                         err = -EINVAL;
2270                         goto done;
2271                 }
2272         } else if (pmc->sfmode != omode) {
2273                 /* allow mode switches for empty-set filters */
2274                 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
2275                 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
2276                         NULL, 0);
2277                 pmc->sfmode = omode;
2278         }
2279
2280         psl = rtnl_dereference(pmc->sflist);
2281         if (!add) {
2282                 if (!psl)
2283                         goto done;      /* err = -EADDRNOTAVAIL */
2284                 rv = !0;
2285                 for (i = 0; i < psl->sl_count; i++) {
2286                         rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2287                                 sizeof(__be32));
2288                         if (rv == 0)
2289                                 break;
2290                 }
2291                 if (rv)         /* source not found */
2292                         goto done;      /* err = -EADDRNOTAVAIL */
2293
2294                 /* special case - (INCLUDE, empty) == LEAVE_GROUP */
2295                 if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
2296                         leavegroup = 1;
2297                         goto done;
2298                 }
2299
2300                 /* update the interface filter */
2301                 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2302                         &mreqs->imr_sourceaddr, 1);
2303
2304                 for (j = i+1; j < psl->sl_count; j++)
2305                         psl->sl_addr[j-1] = psl->sl_addr[j];
2306                 psl->sl_count--;
2307                 err = 0;
2308                 goto done;
2309         }
2310         /* else, add a new source to the filter */
2311
2312         if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) {
2313                 err = -ENOBUFS;
2314                 goto done;
2315         }
2316         if (!psl || psl->sl_count == psl->sl_max) {
2317                 struct ip_sf_socklist *newpsl;
2318                 int count = IP_SFBLOCK;
2319
2320                 if (psl)
2321                         count += psl->sl_max;
2322                 newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
2323                 if (!newpsl) {
2324                         err = -ENOBUFS;
2325                         goto done;
2326                 }
2327                 newpsl->sl_max = count;
2328                 newpsl->sl_count = count - IP_SFBLOCK;
2329                 if (psl) {
2330                         for (i = 0; i < psl->sl_count; i++)
2331                                 newpsl->sl_addr[i] = psl->sl_addr[i];
2332                         /* decrease mem now to avoid the memleak warning */
2333                         atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2334                         kfree_rcu(psl, rcu);
2335                 }
2336                 rcu_assign_pointer(pmc->sflist, newpsl);
2337                 psl = newpsl;
2338         }
2339         rv = 1; /* > 0 for insert logic below if sl_count is 0 */
2340         for (i = 0; i < psl->sl_count; i++) {
2341                 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2342                         sizeof(__be32));
2343                 if (rv == 0)
2344                         break;
2345         }
2346         if (rv == 0)            /* address already there is an error */
2347                 goto done;
2348         for (j = psl->sl_count-1; j >= i; j--)
2349                 psl->sl_addr[j+1] = psl->sl_addr[j];
2350         psl->sl_addr[i] = mreqs->imr_sourceaddr;
2351         psl->sl_count++;
2352         err = 0;
2353         /* update the interface list */
2354         ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2355                 &mreqs->imr_sourceaddr, 1);
2356 done:
2357         if (leavegroup)
2358                 err = ip_mc_leave_group(sk, &imr);
2359         return err;
2360 }
2361
2362 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2363 {
2364         int err = 0;
2365         struct ip_mreqn imr;
2366         __be32 addr = msf->imsf_multiaddr;
2367         struct ip_mc_socklist *pmc;
2368         struct in_device *in_dev;
2369         struct inet_sock *inet = inet_sk(sk);
2370         struct ip_sf_socklist *newpsl, *psl;
2371         struct net *net = sock_net(sk);
2372         int leavegroup = 0;
2373
2374         if (!ipv4_is_multicast(addr))
2375                 return -EINVAL;
2376         if (msf->imsf_fmode != MCAST_INCLUDE &&
2377             msf->imsf_fmode != MCAST_EXCLUDE)
2378                 return -EINVAL;
2379
2380         ASSERT_RTNL();
2381
2382         imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2383         imr.imr_address.s_addr = msf->imsf_interface;
2384         imr.imr_ifindex = ifindex;
2385         in_dev = ip_mc_find_dev(net, &imr);
2386
2387         if (!in_dev) {
2388                 err = -ENODEV;
2389                 goto done;
2390         }
2391
2392         /* special case - (INCLUDE, empty) == LEAVE_GROUP */
2393         if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2394                 leavegroup = 1;
2395                 goto done;
2396         }
2397
2398         for_each_pmc_rtnl(inet, pmc) {
2399                 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2400                     pmc->multi.imr_ifindex == imr.imr_ifindex)
2401                         break;
2402         }
2403         if (!pmc) {             /* must have a prior join */
2404                 err = -EINVAL;
2405                 goto done;
2406         }
2407         if (msf->imsf_numsrc) {
2408                 newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2409                                                            GFP_KERNEL);
2410                 if (!newpsl) {
2411                         err = -ENOBUFS;
2412                         goto done;
2413                 }
2414                 newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2415                 memcpy(newpsl->sl_addr, msf->imsf_slist,
2416                         msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2417                 err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2418                         msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2419                 if (err) {
2420                         sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2421                         goto done;
2422                 }
2423         } else {
2424                 newpsl = NULL;
2425                 (void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2426                                      msf->imsf_fmode, 0, NULL, 0);
2427         }
2428         psl = rtnl_dereference(pmc->sflist);
2429         if (psl) {
2430                 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2431                         psl->sl_count, psl->sl_addr, 0);
2432                 /* decrease mem now to avoid the memleak warning */
2433                 atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2434                 kfree_rcu(psl, rcu);
2435         } else
2436                 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2437                         0, NULL, 0);
2438         rcu_assign_pointer(pmc->sflist, newpsl);
2439         pmc->sfmode = msf->imsf_fmode;
2440         err = 0;
2441 done:
2442         if (leavegroup)
2443                 err = ip_mc_leave_group(sk, &imr);
2444         return err;
2445 }
2446
2447 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2448         struct ip_msfilter __user *optval, int __user *optlen)
2449 {
2450         int err, len, count, copycount;
2451         struct ip_mreqn imr;
2452         __be32 addr = msf->imsf_multiaddr;
2453         struct ip_mc_socklist *pmc;
2454         struct in_device *in_dev;
2455         struct inet_sock *inet = inet_sk(sk);
2456         struct ip_sf_socklist *psl;
2457         struct net *net = sock_net(sk);
2458
2459         ASSERT_RTNL();
2460
2461         if (!ipv4_is_multicast(addr))
2462                 return -EINVAL;
2463
2464         imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2465         imr.imr_address.s_addr = msf->imsf_interface;
2466         imr.imr_ifindex = 0;
2467         in_dev = ip_mc_find_dev(net, &imr);
2468
2469         if (!in_dev) {
2470                 err = -ENODEV;
2471                 goto done;
2472         }
2473         err = -EADDRNOTAVAIL;
2474
2475         for_each_pmc_rtnl(inet, pmc) {
2476                 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2477                     pmc->multi.imr_ifindex == imr.imr_ifindex)
2478                         break;
2479         }
2480         if (!pmc)               /* must have a prior join */
2481                 goto done;
2482         msf->imsf_fmode = pmc->sfmode;
2483         psl = rtnl_dereference(pmc->sflist);
2484         if (!psl) {
2485                 len = 0;
2486                 count = 0;
2487         } else {
2488                 count = psl->sl_count;
2489         }
2490         copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2491         len = copycount * sizeof(psl->sl_addr[0]);
2492         msf->imsf_numsrc = count;
2493         if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2494             copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2495                 return -EFAULT;
2496         }
2497         if (len &&
2498             copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2499                 return -EFAULT;
2500         return 0;
2501 done:
2502         return err;
2503 }
2504
2505 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2506         struct group_filter __user *optval, int __user *optlen)
2507 {
2508         int err, i, count, copycount;
2509         struct sockaddr_in *psin;
2510         __be32 addr;
2511         struct ip_mc_socklist *pmc;
2512         struct inet_sock *inet = inet_sk(sk);
2513         struct ip_sf_socklist *psl;
2514
2515         ASSERT_RTNL();
2516
2517         psin = (struct sockaddr_in *)&gsf->gf_group;
2518         if (psin->sin_family != AF_INET)
2519                 return -EINVAL;
2520         addr = psin->sin_addr.s_addr;
2521         if (!ipv4_is_multicast(addr))
2522                 return -EINVAL;
2523
2524         err = -EADDRNOTAVAIL;
2525
2526         for_each_pmc_rtnl(inet, pmc) {
2527                 if (pmc->multi.imr_multiaddr.s_addr == addr &&
2528                     pmc->multi.imr_ifindex == gsf->gf_interface)
2529                         break;
2530         }
2531         if (!pmc)               /* must have a prior join */
2532                 goto done;
2533         gsf->gf_fmode = pmc->sfmode;
2534         psl = rtnl_dereference(pmc->sflist);
2535         count = psl ? psl->sl_count : 0;
2536         copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2537         gsf->gf_numsrc = count;
2538         if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2539             copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2540                 return -EFAULT;
2541         }
2542         for (i = 0; i < copycount; i++) {
2543                 struct sockaddr_storage ss;
2544
2545                 psin = (struct sockaddr_in *)&ss;
2546                 memset(&ss, 0, sizeof(ss));
2547                 psin->sin_family = AF_INET;
2548                 psin->sin_addr.s_addr = psl->sl_addr[i];
2549                 if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2550                         return -EFAULT;
2551         }
2552         return 0;
2553 done:
2554         return err;
2555 }
2556
2557 /*
2558  * check if a multicast source filter allows delivery for a given <src,dst,intf>
2559  */
2560 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif)
2561 {
2562         struct inet_sock *inet = inet_sk(sk);
2563         struct ip_mc_socklist *pmc;
2564         struct ip_sf_socklist *psl;
2565         int i;
2566         int ret;
2567
2568         ret = 1;
2569         if (!ipv4_is_multicast(loc_addr))
2570                 goto out;
2571
2572         rcu_read_lock();
2573         for_each_pmc_rcu(inet, pmc) {
2574                 if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2575                     pmc->multi.imr_ifindex == dif)
2576                         break;
2577         }
2578         ret = inet->mc_all;
2579         if (!pmc)
2580                 goto unlock;
2581         psl = rcu_dereference(pmc->sflist);
2582         ret = (pmc->sfmode == MCAST_EXCLUDE);
2583         if (!psl)
2584                 goto unlock;
2585
2586         for (i = 0; i < psl->sl_count; i++) {
2587                 if (psl->sl_addr[i] == rmt_addr)
2588                         break;
2589         }
2590         ret = 0;
2591         if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2592                 goto unlock;
2593         if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2594                 goto unlock;
2595         ret = 1;
2596 unlock:
2597         rcu_read_unlock();
2598 out:
2599         return ret;
2600 }
2601
2602 /*
2603  *      A socket is closing.
2604  */
2605
2606 void ip_mc_drop_socket(struct sock *sk)
2607 {
2608         struct inet_sock *inet = inet_sk(sk);
2609         struct ip_mc_socklist *iml;
2610         struct net *net = sock_net(sk);
2611
2612         if (!inet->mc_list)
2613                 return;
2614
2615         rtnl_lock();
2616         while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2617                 struct in_device *in_dev;
2618
2619                 inet->mc_list = iml->next_rcu;
2620                 in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2621                 (void) ip_mc_leave_src(sk, iml, in_dev);
2622                 if (in_dev)
2623                         ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2624                 /* decrease mem now to avoid the memleak warning */
2625                 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2626                 kfree_rcu(iml, rcu);
2627         }
2628         rtnl_unlock();
2629 }
2630
2631 /* called with rcu_read_lock() */
2632 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto)
2633 {
2634         struct ip_mc_list *im;
2635         struct ip_mc_list __rcu **mc_hash;
2636         struct ip_sf_list *psf;
2637         int rv = 0;
2638
2639         mc_hash = rcu_dereference(in_dev->mc_hash);
2640         if (mc_hash) {
2641                 u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
2642
2643                 for (im = rcu_dereference(mc_hash[hash]);
2644                      im != NULL;
2645                      im = rcu_dereference(im->next_hash)) {
2646                         if (im->multiaddr == mc_addr)
2647                                 break;
2648                 }
2649         } else {
2650                 for_each_pmc_rcu(in_dev, im) {
2651                         if (im->multiaddr == mc_addr)
2652                                 break;
2653                 }
2654         }
2655         if (im && proto == IPPROTO_IGMP) {
2656                 rv = 1;
2657         } else if (im) {
2658                 if (src_addr) {
2659                         for (psf = im->sources; psf; psf = psf->sf_next) {
2660                                 if (psf->sf_inaddr == src_addr)
2661                                         break;
2662                         }
2663                         if (psf)
2664                                 rv = psf->sf_count[MCAST_INCLUDE] ||
2665                                         psf->sf_count[MCAST_EXCLUDE] !=
2666                                         im->sfcount[MCAST_EXCLUDE];
2667                         else
2668                                 rv = im->sfcount[MCAST_EXCLUDE] != 0;
2669                 } else
2670                         rv = 1; /* unspecified source; tentatively allow */
2671         }
2672         return rv;
2673 }
2674
2675 #if defined(CONFIG_PROC_FS)
2676 struct igmp_mc_iter_state {
2677         struct seq_net_private p;
2678         struct net_device *dev;
2679         struct in_device *in_dev;
2680 };
2681
2682 #define igmp_mc_seq_private(seq)        ((struct igmp_mc_iter_state *)(seq)->private)
2683
2684 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2685 {
2686         struct net *net = seq_file_net(seq);
2687         struct ip_mc_list *im = NULL;
2688         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2689
2690         state->in_dev = NULL;
2691         for_each_netdev_rcu(net, state->dev) {
2692                 struct in_device *in_dev;
2693
2694                 in_dev = __in_dev_get_rcu(state->dev);
2695                 if (!in_dev)
2696                         continue;
2697                 im = rcu_dereference(in_dev->mc_list);
2698                 if (im) {
2699                         state->in_dev = in_dev;
2700                         break;
2701                 }
2702         }
2703         return im;
2704 }
2705
2706 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2707 {
2708         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2709
2710         im = rcu_dereference(im->next_rcu);
2711         while (!im) {
2712                 state->dev = next_net_device_rcu(state->dev);
2713                 if (!state->dev) {
2714                         state->in_dev = NULL;
2715                         break;
2716                 }
2717                 state->in_dev = __in_dev_get_rcu(state->dev);
2718                 if (!state->in_dev)
2719                         continue;
2720                 im = rcu_dereference(state->in_dev->mc_list);
2721         }
2722         return im;
2723 }
2724
2725 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2726 {
2727         struct ip_mc_list *im = igmp_mc_get_first(seq);
2728         if (im)
2729                 while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2730                         --pos;
2731         return pos ? NULL : im;
2732 }
2733
2734 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2735         __acquires(rcu)
2736 {
2737         rcu_read_lock();
2738         return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2739 }
2740
2741 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2742 {
2743         struct ip_mc_list *im;
2744         if (v == SEQ_START_TOKEN)
2745                 im = igmp_mc_get_first(seq);
2746         else
2747                 im = igmp_mc_get_next(seq, v);
2748         ++*pos;
2749         return im;
2750 }
2751
2752 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2753         __releases(rcu)
2754 {
2755         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2756
2757         state->in_dev = NULL;
2758         state->dev = NULL;
2759         rcu_read_unlock();
2760 }
2761
2762 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2763 {
2764         if (v == SEQ_START_TOKEN)
2765                 seq_puts(seq,
2766                          "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2767         else {
2768                 struct ip_mc_list *im = (struct ip_mc_list *)v;
2769                 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2770                 char   *querier;
2771                 long delta;
2772
2773 #ifdef CONFIG_IP_MULTICAST
2774                 querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2775                           IGMP_V2_SEEN(state->in_dev) ? "V2" :
2776                           "V3";
2777 #else
2778                 querier = "NONE";
2779 #endif
2780
2781                 if (rcu_access_pointer(state->in_dev->mc_list) == im) {
2782                         seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2783                                    state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2784                 }
2785
2786                 delta = im->timer.expires - jiffies;
2787                 seq_printf(seq,
2788                            "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2789                            im->multiaddr, im->users,
2790                            im->tm_running,
2791                            im->tm_running ? jiffies_delta_to_clock_t(delta) : 0,
2792                            im->reporter);
2793         }
2794         return 0;
2795 }
2796
2797 static const struct seq_operations igmp_mc_seq_ops = {
2798         .start  =       igmp_mc_seq_start,
2799         .next   =       igmp_mc_seq_next,
2800         .stop   =       igmp_mc_seq_stop,
2801         .show   =       igmp_mc_seq_show,
2802 };
2803
2804 static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2805 {
2806         return seq_open_net(inode, file, &igmp_mc_seq_ops,
2807                         sizeof(struct igmp_mc_iter_state));
2808 }
2809
2810 static const struct file_operations igmp_mc_seq_fops = {
2811         .owner          =       THIS_MODULE,
2812         .open           =       igmp_mc_seq_open,
2813         .read           =       seq_read,
2814         .llseek         =       seq_lseek,
2815         .release        =       seq_release_net,
2816 };
2817
2818 struct igmp_mcf_iter_state {
2819         struct seq_net_private p;
2820         struct net_device *dev;
2821         struct in_device *idev;
2822         struct ip_mc_list *im;
2823 };
2824
2825 #define igmp_mcf_seq_private(seq)       ((struct igmp_mcf_iter_state *)(seq)->private)
2826
2827 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2828 {
2829         struct net *net = seq_file_net(seq);
2830         struct ip_sf_list *psf = NULL;
2831         struct ip_mc_list *im = NULL;
2832         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2833
2834         state->idev = NULL;
2835         state->im = NULL;
2836         for_each_netdev_rcu(net, state->dev) {
2837                 struct in_device *idev;
2838                 idev = __in_dev_get_rcu(state->dev);
2839                 if (unlikely(!idev))
2840                         continue;
2841                 im = rcu_dereference(idev->mc_list);
2842                 if (likely(im)) {
2843                         spin_lock_bh(&im->lock);
2844                         psf = im->sources;
2845                         if (likely(psf)) {
2846                                 state->im = im;
2847                                 state->idev = idev;
2848                                 break;
2849                         }
2850                         spin_unlock_bh(&im->lock);
2851                 }
2852         }
2853         return psf;
2854 }
2855
2856 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2857 {
2858         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2859
2860         psf = psf->sf_next;
2861         while (!psf) {
2862                 spin_unlock_bh(&state->im->lock);
2863                 state->im = state->im->next;
2864                 while (!state->im) {
2865                         state->dev = next_net_device_rcu(state->dev);
2866                         if (!state->dev) {
2867                                 state->idev = NULL;
2868                                 goto out;
2869                         }
2870                         state->idev = __in_dev_get_rcu(state->dev);
2871                         if (!state->idev)
2872                                 continue;
2873                         state->im = rcu_dereference(state->idev->mc_list);
2874                 }
2875                 if (!state->im)
2876                         break;
2877                 spin_lock_bh(&state->im->lock);
2878                 psf = state->im->sources;
2879         }
2880 out:
2881         return psf;
2882 }
2883
2884 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2885 {
2886         struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2887         if (psf)
2888                 while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2889                         --pos;
2890         return pos ? NULL : psf;
2891 }
2892
2893 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2894         __acquires(rcu)
2895 {
2896         rcu_read_lock();
2897         return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2898 }
2899
2900 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2901 {
2902         struct ip_sf_list *psf;
2903         if (v == SEQ_START_TOKEN)
2904                 psf = igmp_mcf_get_first(seq);
2905         else
2906                 psf = igmp_mcf_get_next(seq, v);
2907         ++*pos;
2908         return psf;
2909 }
2910
2911 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2912         __releases(rcu)
2913 {
2914         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2915         if (likely(state->im)) {
2916                 spin_unlock_bh(&state->im->lock);
2917                 state->im = NULL;
2918         }
2919         state->idev = NULL;
2920         state->dev = NULL;
2921         rcu_read_unlock();
2922 }
2923
2924 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2925 {
2926         struct ip_sf_list *psf = (struct ip_sf_list *)v;
2927         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2928
2929         if (v == SEQ_START_TOKEN) {
2930                 seq_puts(seq, "Idx Device        MCA        SRC    INC    EXC\n");
2931         } else {
2932                 seq_printf(seq,
2933                            "%3d %6.6s 0x%08x "
2934                            "0x%08x %6lu %6lu\n",
2935                            state->dev->ifindex, state->dev->name,
2936                            ntohl(state->im->multiaddr),
2937                            ntohl(psf->sf_inaddr),
2938                            psf->sf_count[MCAST_INCLUDE],
2939                            psf->sf_count[MCAST_EXCLUDE]);
2940         }
2941         return 0;
2942 }
2943
2944 static const struct seq_operations igmp_mcf_seq_ops = {
2945         .start  =       igmp_mcf_seq_start,
2946         .next   =       igmp_mcf_seq_next,
2947         .stop   =       igmp_mcf_seq_stop,
2948         .show   =       igmp_mcf_seq_show,
2949 };
2950
2951 static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2952 {
2953         return seq_open_net(inode, file, &igmp_mcf_seq_ops,
2954                         sizeof(struct igmp_mcf_iter_state));
2955 }
2956
2957 static const struct file_operations igmp_mcf_seq_fops = {
2958         .owner          =       THIS_MODULE,
2959         .open           =       igmp_mcf_seq_open,
2960         .read           =       seq_read,
2961         .llseek         =       seq_lseek,
2962         .release        =       seq_release_net,
2963 };
2964
2965 static int __net_init igmp_net_init(struct net *net)
2966 {
2967         struct proc_dir_entry *pde;
2968         int err;
2969
2970         pde = proc_create("igmp", S_IRUGO, net->proc_net, &igmp_mc_seq_fops);
2971         if (!pde)
2972                 goto out_igmp;
2973         pde = proc_create("mcfilter", S_IRUGO, net->proc_net,
2974                           &igmp_mcf_seq_fops);
2975         if (!pde)
2976                 goto out_mcfilter;
2977         err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET,
2978                                    SOCK_DGRAM, 0, net);
2979         if (err < 0) {
2980                 pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n",
2981                        err);
2982                 goto out_sock;
2983         }
2984
2985         return 0;
2986
2987 out_sock:
2988         remove_proc_entry("mcfilter", net->proc_net);
2989 out_mcfilter:
2990         remove_proc_entry("igmp", net->proc_net);
2991 out_igmp:
2992         return -ENOMEM;
2993 }
2994
2995 static void __net_exit igmp_net_exit(struct net *net)
2996 {
2997         remove_proc_entry("mcfilter", net->proc_net);
2998         remove_proc_entry("igmp", net->proc_net);
2999         inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk);
3000 }
3001
3002 static struct pernet_operations igmp_net_ops = {
3003         .init = igmp_net_init,
3004         .exit = igmp_net_exit,
3005 };
3006 #endif
3007
3008 static int igmp_netdev_event(struct notifier_block *this,
3009                              unsigned long event, void *ptr)
3010 {
3011         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3012         struct in_device *in_dev;
3013
3014         switch (event) {
3015         case NETDEV_RESEND_IGMP:
3016                 in_dev = __in_dev_get_rtnl(dev);
3017                 if (in_dev)
3018                         ip_mc_rejoin_groups(in_dev);
3019                 break;
3020         default:
3021                 break;
3022         }
3023         return NOTIFY_DONE;
3024 }
3025
3026 static struct notifier_block igmp_notifier = {
3027         .notifier_call = igmp_netdev_event,
3028 };
3029
3030 int __init igmp_mc_init(void)
3031 {
3032 #if defined(CONFIG_PROC_FS)
3033         int err;
3034
3035         err = register_pernet_subsys(&igmp_net_ops);
3036         if (err)
3037                 return err;
3038         err = register_netdevice_notifier(&igmp_notifier);
3039         if (err)
3040                 goto reg_notif_fail;
3041         return 0;
3042
3043 reg_notif_fail:
3044         unregister_pernet_subsys(&igmp_net_ops);
3045         return err;
3046 #else
3047         return register_netdevice_notifier(&igmp_notifier);
3048 #endif
3049 }