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 (atomic_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                 atomic_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                 atomic_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                 atomic_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 in_device *in_dev = __in_dev_get_rcu(skb->dev);
1011         int len = skb->len;
1012         bool dropped = true;
1013
1014         if (!in_dev)
1015                 goto drop;
1016
1017         if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
1018                 goto drop;
1019
1020         if (skb_checksum_simple_validate(skb))
1021                 goto drop;
1022
1023         ih = igmp_hdr(skb);
1024         switch (ih->type) {
1025         case IGMP_HOST_MEMBERSHIP_QUERY:
1026                 dropped = igmp_heard_query(in_dev, skb, len);
1027                 break;
1028         case IGMP_HOST_MEMBERSHIP_REPORT:
1029         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1030                 /* Is it our report looped back? */
1031                 if (rt_is_output_route(skb_rtable(skb)))
1032                         break;
1033                 /* don't rely on MC router hearing unicast reports */
1034                 if (skb->pkt_type == PACKET_MULTICAST ||
1035                     skb->pkt_type == PACKET_BROADCAST)
1036                         dropped = igmp_heard_report(in_dev, ih->group);
1037                 break;
1038         case IGMP_PIM:
1039 #ifdef CONFIG_IP_PIMSM_V1
1040                 return pim_rcv_v1(skb);
1041 #endif
1042         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1043         case IGMP_DVMRP:
1044         case IGMP_TRACE:
1045         case IGMP_HOST_LEAVE_MESSAGE:
1046         case IGMP_MTRACE:
1047         case IGMP_MTRACE_RESP:
1048                 break;
1049         default:
1050                 break;
1051         }
1052
1053 drop:
1054         if (dropped)
1055                 kfree_skb(skb);
1056         else
1057                 consume_skb(skb);
1058         return 0;
1059 }
1060
1061 #endif
1062
1063
1064 /*
1065  *      Add a filter to a device
1066  */
1067
1068 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1069 {
1070         char buf[MAX_ADDR_LEN];
1071         struct net_device *dev = in_dev->dev;
1072
1073         /* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1074            We will get multicast token leakage, when IFF_MULTICAST
1075            is changed. This check should be done in ndo_set_rx_mode
1076            routine. Something sort of:
1077            if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1078            --ANK
1079            */
1080         if (arp_mc_map(addr, buf, dev, 0) == 0)
1081                 dev_mc_add(dev, buf);
1082 }
1083
1084 /*
1085  *      Remove a filter from a device
1086  */
1087
1088 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1089 {
1090         char buf[MAX_ADDR_LEN];
1091         struct net_device *dev = in_dev->dev;
1092
1093         if (arp_mc_map(addr, buf, dev, 0) == 0)
1094                 dev_mc_del(dev, buf);
1095 }
1096
1097 #ifdef CONFIG_IP_MULTICAST
1098 /*
1099  * deleted ip_mc_list manipulation
1100  */
1101 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1102 {
1103         struct ip_mc_list *pmc;
1104         struct net *net = dev_net(in_dev->dev);
1105
1106         /* this is an "ip_mc_list" for convenience; only the fields below
1107          * are actually used. In particular, the refcnt and users are not
1108          * used for management of the delete list. Using the same structure
1109          * for deleted items allows change reports to use common code with
1110          * non-deleted or query-response MCA's.
1111          */
1112         pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
1113         if (!pmc)
1114                 return;
1115         spin_lock_init(&pmc->lock);
1116         spin_lock_bh(&im->lock);
1117         pmc->interface = im->interface;
1118         in_dev_hold(in_dev);
1119         pmc->multiaddr = im->multiaddr;
1120         pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1121         pmc->sfmode = im->sfmode;
1122         if (pmc->sfmode == MCAST_INCLUDE) {
1123                 struct ip_sf_list *psf;
1124
1125                 pmc->tomb = im->tomb;
1126                 pmc->sources = im->sources;
1127                 im->tomb = im->sources = NULL;
1128                 for (psf = pmc->sources; psf; psf = psf->sf_next)
1129                         psf->sf_crcount = pmc->crcount;
1130         }
1131         spin_unlock_bh(&im->lock);
1132
1133         spin_lock_bh(&in_dev->mc_tomb_lock);
1134         pmc->next = in_dev->mc_tomb;
1135         in_dev->mc_tomb = pmc;
1136         spin_unlock_bh(&in_dev->mc_tomb_lock);
1137 }
1138
1139 /*
1140  * restore ip_mc_list deleted records
1141  */
1142 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1143 {
1144         struct ip_mc_list *pmc, *pmc_prev;
1145         struct ip_sf_list *psf;
1146         struct net *net = dev_net(in_dev->dev);
1147         __be32 multiaddr = im->multiaddr;
1148
1149         spin_lock_bh(&in_dev->mc_tomb_lock);
1150         pmc_prev = NULL;
1151         for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) {
1152                 if (pmc->multiaddr == multiaddr)
1153                         break;
1154                 pmc_prev = pmc;
1155         }
1156         if (pmc) {
1157                 if (pmc_prev)
1158                         pmc_prev->next = pmc->next;
1159                 else
1160                         in_dev->mc_tomb = pmc->next;
1161         }
1162         spin_unlock_bh(&in_dev->mc_tomb_lock);
1163
1164         spin_lock_bh(&im->lock);
1165         if (pmc) {
1166                 im->interface = pmc->interface;
1167                 im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1168                 im->sfmode = pmc->sfmode;
1169                 if (pmc->sfmode == MCAST_INCLUDE) {
1170                         im->tomb = pmc->tomb;
1171                         im->sources = pmc->sources;
1172                         for (psf = im->sources; psf; psf = psf->sf_next)
1173                                 psf->sf_crcount = im->crcount;
1174                 }
1175                 in_dev_put(pmc->interface);
1176                 kfree(pmc);
1177         }
1178         spin_unlock_bh(&im->lock);
1179 }
1180
1181 /*
1182  * flush ip_mc_list deleted records
1183  */
1184 static void igmpv3_clear_delrec(struct in_device *in_dev)
1185 {
1186         struct ip_mc_list *pmc, *nextpmc;
1187
1188         spin_lock_bh(&in_dev->mc_tomb_lock);
1189         pmc = in_dev->mc_tomb;
1190         in_dev->mc_tomb = NULL;
1191         spin_unlock_bh(&in_dev->mc_tomb_lock);
1192
1193         for (; pmc; pmc = nextpmc) {
1194                 nextpmc = pmc->next;
1195                 ip_mc_clear_src(pmc);
1196                 in_dev_put(pmc->interface);
1197                 kfree(pmc);
1198         }
1199         /* clear dead sources, too */
1200         rcu_read_lock();
1201         for_each_pmc_rcu(in_dev, pmc) {
1202                 struct ip_sf_list *psf, *psf_next;
1203
1204                 spin_lock_bh(&pmc->lock);
1205                 psf = pmc->tomb;
1206                 pmc->tomb = NULL;
1207                 spin_unlock_bh(&pmc->lock);
1208                 for (; psf; psf = psf_next) {
1209                         psf_next = psf->sf_next;
1210                         kfree(psf);
1211                 }
1212         }
1213         rcu_read_unlock();
1214 }
1215 #endif
1216
1217 static void igmp_group_dropped(struct ip_mc_list *im)
1218 {
1219         struct in_device *in_dev = im->interface;
1220 #ifdef CONFIG_IP_MULTICAST
1221         struct net *net = dev_net(in_dev->dev);
1222         int reporter;
1223 #endif
1224
1225         if (im->loaded) {
1226                 im->loaded = 0;
1227                 ip_mc_filter_del(in_dev, im->multiaddr);
1228         }
1229
1230 #ifdef CONFIG_IP_MULTICAST
1231         if (im->multiaddr == IGMP_ALL_HOSTS)
1232                 return;
1233         if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1234                 return;
1235
1236         reporter = im->reporter;
1237         igmp_stop_timer(im);
1238
1239         if (!in_dev->dead) {
1240                 if (IGMP_V1_SEEN(in_dev))
1241                         return;
1242                 if (IGMP_V2_SEEN(in_dev)) {
1243                         if (reporter)
1244                                 igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1245                         return;
1246                 }
1247                 /* IGMPv3 */
1248                 igmpv3_add_delrec(in_dev, im);
1249
1250                 igmp_ifc_event(in_dev);
1251         }
1252 #endif
1253 }
1254
1255 static void igmp_group_added(struct ip_mc_list *im)
1256 {
1257         struct in_device *in_dev = im->interface;
1258 #ifdef CONFIG_IP_MULTICAST
1259         struct net *net = dev_net(in_dev->dev);
1260 #endif
1261
1262         if (im->loaded == 0) {
1263                 im->loaded = 1;
1264                 ip_mc_filter_add(in_dev, im->multiaddr);
1265         }
1266
1267 #ifdef CONFIG_IP_MULTICAST
1268         if (im->multiaddr == IGMP_ALL_HOSTS)
1269                 return;
1270         if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1271                 return;
1272
1273         if (in_dev->dead)
1274                 return;
1275         if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1276                 spin_lock_bh(&im->lock);
1277                 igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY);
1278                 spin_unlock_bh(&im->lock);
1279                 return;
1280         }
1281         /* else, v3 */
1282
1283         im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1284         igmp_ifc_event(in_dev);
1285 #endif
1286 }
1287
1288
1289 /*
1290  *      Multicast list managers
1291  */
1292
1293 static u32 ip_mc_hash(const struct ip_mc_list *im)
1294 {
1295         return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
1296 }
1297
1298 static void ip_mc_hash_add(struct in_device *in_dev,
1299                            struct ip_mc_list *im)
1300 {
1301         struct ip_mc_list __rcu **mc_hash;
1302         u32 hash;
1303
1304         mc_hash = rtnl_dereference(in_dev->mc_hash);
1305         if (mc_hash) {
1306                 hash = ip_mc_hash(im);
1307                 im->next_hash = mc_hash[hash];
1308                 rcu_assign_pointer(mc_hash[hash], im);
1309                 return;
1310         }
1311
1312         /* do not use a hash table for small number of items */
1313         if (in_dev->mc_count < 4)
1314                 return;
1315
1316         mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
1317                           GFP_KERNEL);
1318         if (!mc_hash)
1319                 return;
1320
1321         for_each_pmc_rtnl(in_dev, im) {
1322                 hash = ip_mc_hash(im);
1323                 im->next_hash = mc_hash[hash];
1324                 RCU_INIT_POINTER(mc_hash[hash], im);
1325         }
1326
1327         rcu_assign_pointer(in_dev->mc_hash, mc_hash);
1328 }
1329
1330 static void ip_mc_hash_remove(struct in_device *in_dev,
1331                               struct ip_mc_list *im)
1332 {
1333         struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
1334         struct ip_mc_list *aux;
1335
1336         if (!mc_hash)
1337                 return;
1338         mc_hash += ip_mc_hash(im);
1339         while ((aux = rtnl_dereference(*mc_hash)) != im)
1340                 mc_hash = &aux->next_hash;
1341         *mc_hash = im->next_hash;
1342 }
1343
1344
1345 /*
1346  *      A socket has joined a multicast group on device dev.
1347  */
1348
1349 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1350 {
1351         struct ip_mc_list *im;
1352 #ifdef CONFIG_IP_MULTICAST
1353         struct net *net = dev_net(in_dev->dev);
1354 #endif
1355
1356         ASSERT_RTNL();
1357
1358         for_each_pmc_rtnl(in_dev, im) {
1359                 if (im->multiaddr == addr) {
1360                         im->users++;
1361                         ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1362                         goto out;
1363                 }
1364         }
1365
1366         im = kzalloc(sizeof(*im), GFP_KERNEL);
1367         if (!im)
1368                 goto out;
1369
1370         im->users = 1;
1371         im->interface = in_dev;
1372         in_dev_hold(in_dev);
1373         im->multiaddr = addr;
1374         /* initial mode is (EX, empty) */
1375         im->sfmode = MCAST_EXCLUDE;
1376         im->sfcount[MCAST_EXCLUDE] = 1;
1377         atomic_set(&im->refcnt, 1);
1378         spin_lock_init(&im->lock);
1379 #ifdef CONFIG_IP_MULTICAST
1380         setup_timer(&im->timer, igmp_timer_expire, (unsigned long)im);
1381         im->unsolicit_count = net->ipv4.sysctl_igmp_qrv;
1382 #endif
1383
1384         im->next_rcu = in_dev->mc_list;
1385         in_dev->mc_count++;
1386         rcu_assign_pointer(in_dev->mc_list, im);
1387
1388         ip_mc_hash_add(in_dev, im);
1389
1390 #ifdef CONFIG_IP_MULTICAST
1391         igmpv3_del_delrec(in_dev, im);
1392 #endif
1393         igmp_group_added(im);
1394         if (!in_dev->dead)
1395                 ip_rt_multicast_event(in_dev);
1396 out:
1397         return;
1398 }
1399 EXPORT_SYMBOL(ip_mc_inc_group);
1400
1401 static int ip_mc_check_iphdr(struct sk_buff *skb)
1402 {
1403         const struct iphdr *iph;
1404         unsigned int len;
1405         unsigned int offset = skb_network_offset(skb) + sizeof(*iph);
1406
1407         if (!pskb_may_pull(skb, offset))
1408                 return -EINVAL;
1409
1410         iph = ip_hdr(skb);
1411
1412         if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph))
1413                 return -EINVAL;
1414
1415         offset += ip_hdrlen(skb) - sizeof(*iph);
1416
1417         if (!pskb_may_pull(skb, offset))
1418                 return -EINVAL;
1419
1420         iph = ip_hdr(skb);
1421
1422         if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1423                 return -EINVAL;
1424
1425         len = skb_network_offset(skb) + ntohs(iph->tot_len);
1426         if (skb->len < len || len < offset)
1427                 return -EINVAL;
1428
1429         skb_set_transport_header(skb, offset);
1430
1431         return 0;
1432 }
1433
1434 static int ip_mc_check_igmp_reportv3(struct sk_buff *skb)
1435 {
1436         unsigned int len = skb_transport_offset(skb);
1437
1438         len += sizeof(struct igmpv3_report);
1439
1440         return pskb_may_pull(skb, len) ? 0 : -EINVAL;
1441 }
1442
1443 static int ip_mc_check_igmp_query(struct sk_buff *skb)
1444 {
1445         unsigned int len = skb_transport_offset(skb);
1446
1447         len += sizeof(struct igmphdr);
1448         if (skb->len < len)
1449                 return -EINVAL;
1450
1451         /* IGMPv{1,2}? */
1452         if (skb->len != len) {
1453                 /* or IGMPv3? */
1454                 len += sizeof(struct igmpv3_query) - sizeof(struct igmphdr);
1455                 if (skb->len < len || !pskb_may_pull(skb, len))
1456                         return -EINVAL;
1457         }
1458
1459         /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1460          * all-systems destination addresses (224.0.0.1) for general queries
1461          */
1462         if (!igmp_hdr(skb)->group &&
1463             ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP))
1464                 return -EINVAL;
1465
1466         return 0;
1467 }
1468
1469 static int ip_mc_check_igmp_msg(struct sk_buff *skb)
1470 {
1471         switch (igmp_hdr(skb)->type) {
1472         case IGMP_HOST_LEAVE_MESSAGE:
1473         case IGMP_HOST_MEMBERSHIP_REPORT:
1474         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1475                 /* fall through */
1476                 return 0;
1477         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1478                 return ip_mc_check_igmp_reportv3(skb);
1479         case IGMP_HOST_MEMBERSHIP_QUERY:
1480                 return ip_mc_check_igmp_query(skb);
1481         default:
1482                 return -ENOMSG;
1483         }
1484 }
1485
1486 static inline __sum16 ip_mc_validate_checksum(struct sk_buff *skb)
1487 {
1488         return skb_checksum_simple_validate(skb);
1489 }
1490
1491 static int __ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
1492
1493 {
1494         struct sk_buff *skb_chk;
1495         unsigned int transport_len;
1496         unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr);
1497         int ret = -EINVAL;
1498
1499         transport_len = ntohs(ip_hdr(skb)->tot_len) - ip_hdrlen(skb);
1500
1501         skb_chk = skb_checksum_trimmed(skb, transport_len,
1502                                        ip_mc_validate_checksum);
1503         if (!skb_chk)
1504                 goto err;
1505
1506         if (!pskb_may_pull(skb_chk, len))
1507                 goto err;
1508
1509         ret = ip_mc_check_igmp_msg(skb_chk);
1510         if (ret)
1511                 goto err;
1512
1513         if (skb_trimmed)
1514                 *skb_trimmed = skb_chk;
1515         /* free now unneeded clone */
1516         else if (skb_chk != skb)
1517                 kfree_skb(skb_chk);
1518
1519         ret = 0;
1520
1521 err:
1522         if (ret && skb_chk && skb_chk != skb)
1523                 kfree_skb(skb_chk);
1524
1525         return ret;
1526 }
1527
1528 /**
1529  * ip_mc_check_igmp - checks whether this is a sane IGMP packet
1530  * @skb: the skb to validate
1531  * @skb_trimmed: to store an skb pointer trimmed to IPv4 packet tail (optional)
1532  *
1533  * Checks whether an IPv4 packet is a valid IGMP packet. If so sets
1534  * skb transport header accordingly and returns zero.
1535  *
1536  * -EINVAL: A broken packet was detected, i.e. it violates some internet
1537  *  standard
1538  * -ENOMSG: IP header validation succeeded but it is not an IGMP packet.
1539  * -ENOMEM: A memory allocation failure happened.
1540  *
1541  * Optionally, an skb pointer might be provided via skb_trimmed (or set it
1542  * to NULL): After parsing an IGMP packet successfully it will point to
1543  * an skb which has its tail aligned to the IP packet end. This might
1544  * either be the originally provided skb or a trimmed, cloned version if
1545  * the skb frame had data beyond the IP packet. A cloned skb allows us
1546  * to leave the original skb and its full frame unchanged (which might be
1547  * desirable for layer 2 frame jugglers).
1548  *
1549  * Caller needs to set the skb network header and free any returned skb if it
1550  * differs from the provided skb.
1551  */
1552 int ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
1553 {
1554         int ret = ip_mc_check_iphdr(skb);
1555
1556         if (ret < 0)
1557                 return ret;
1558
1559         if (ip_hdr(skb)->protocol != IPPROTO_IGMP)
1560                 return -ENOMSG;
1561
1562         return __ip_mc_check_igmp(skb, skb_trimmed);
1563 }
1564 EXPORT_SYMBOL(ip_mc_check_igmp);
1565
1566 /*
1567  *      Resend IGMP JOIN report; used by netdev notifier.
1568  */
1569 static void ip_mc_rejoin_groups(struct in_device *in_dev)
1570 {
1571 #ifdef CONFIG_IP_MULTICAST
1572         struct ip_mc_list *im;
1573         int type;
1574         struct net *net = dev_net(in_dev->dev);
1575
1576         ASSERT_RTNL();
1577
1578         for_each_pmc_rtnl(in_dev, im) {
1579                 if (im->multiaddr == IGMP_ALL_HOSTS)
1580                         continue;
1581                 if (ipv4_is_local_multicast(im->multiaddr) &&
1582                     !net->ipv4.sysctl_igmp_llm_reports)
1583                         continue;
1584
1585                 /* a failover is happening and switches
1586                  * must be notified immediately
1587                  */
1588                 if (IGMP_V1_SEEN(in_dev))
1589                         type = IGMP_HOST_MEMBERSHIP_REPORT;
1590                 else if (IGMP_V2_SEEN(in_dev))
1591                         type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1592                 else
1593                         type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1594                 igmp_send_report(in_dev, im, type);
1595         }
1596 #endif
1597 }
1598
1599 /*
1600  *      A socket has left a multicast group on device dev
1601  */
1602
1603 void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
1604 {
1605         struct ip_mc_list *i;
1606         struct ip_mc_list __rcu **ip;
1607
1608         ASSERT_RTNL();
1609
1610         for (ip = &in_dev->mc_list;
1611              (i = rtnl_dereference(*ip)) != NULL;
1612              ip = &i->next_rcu) {
1613                 if (i->multiaddr == addr) {
1614                         if (--i->users == 0) {
1615                                 ip_mc_hash_remove(in_dev, i);
1616                                 *ip = i->next_rcu;
1617                                 in_dev->mc_count--;
1618                                 igmp_group_dropped(i);
1619                                 ip_mc_clear_src(i);
1620
1621                                 if (!in_dev->dead)
1622                                         ip_rt_multicast_event(in_dev);
1623
1624                                 ip_ma_put(i);
1625                                 return;
1626                         }
1627                         break;
1628                 }
1629         }
1630 }
1631 EXPORT_SYMBOL(ip_mc_dec_group);
1632
1633 /* Device changing type */
1634
1635 void ip_mc_unmap(struct in_device *in_dev)
1636 {
1637         struct ip_mc_list *pmc;
1638
1639         ASSERT_RTNL();
1640
1641         for_each_pmc_rtnl(in_dev, pmc)
1642                 igmp_group_dropped(pmc);
1643 }
1644
1645 void ip_mc_remap(struct in_device *in_dev)
1646 {
1647         struct ip_mc_list *pmc;
1648
1649         ASSERT_RTNL();
1650
1651         for_each_pmc_rtnl(in_dev, pmc) {
1652 #ifdef CONFIG_IP_MULTICAST
1653                 igmpv3_del_delrec(in_dev, pmc);
1654 #endif
1655                 igmp_group_added(pmc);
1656         }
1657 }
1658
1659 /* Device going down */
1660
1661 void ip_mc_down(struct in_device *in_dev)
1662 {
1663         struct ip_mc_list *pmc;
1664
1665         ASSERT_RTNL();
1666
1667         for_each_pmc_rtnl(in_dev, pmc)
1668                 igmp_group_dropped(pmc);
1669
1670 #ifdef CONFIG_IP_MULTICAST
1671         in_dev->mr_ifc_count = 0;
1672         if (del_timer(&in_dev->mr_ifc_timer))
1673                 __in_dev_put(in_dev);
1674         in_dev->mr_gq_running = 0;
1675         if (del_timer(&in_dev->mr_gq_timer))
1676                 __in_dev_put(in_dev);
1677 #endif
1678
1679         ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1680 }
1681
1682 void ip_mc_init_dev(struct in_device *in_dev)
1683 {
1684 #ifdef CONFIG_IP_MULTICAST
1685         struct net *net = dev_net(in_dev->dev);
1686 #endif
1687         ASSERT_RTNL();
1688
1689 #ifdef CONFIG_IP_MULTICAST
1690         setup_timer(&in_dev->mr_gq_timer, igmp_gq_timer_expire,
1691                         (unsigned long)in_dev);
1692         setup_timer(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire,
1693                         (unsigned long)in_dev);
1694         in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1695 #endif
1696
1697         spin_lock_init(&in_dev->mc_tomb_lock);
1698 }
1699
1700 /* Device going up */
1701
1702 void ip_mc_up(struct in_device *in_dev)
1703 {
1704         struct ip_mc_list *pmc;
1705 #ifdef CONFIG_IP_MULTICAST
1706         struct net *net = dev_net(in_dev->dev);
1707 #endif
1708
1709         ASSERT_RTNL();
1710
1711 #ifdef CONFIG_IP_MULTICAST
1712         in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1713 #endif
1714         ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1715
1716         for_each_pmc_rtnl(in_dev, pmc) {
1717 #ifdef CONFIG_IP_MULTICAST
1718                 igmpv3_del_delrec(in_dev, pmc);
1719 #endif
1720                 igmp_group_added(pmc);
1721         }
1722 }
1723
1724 /*
1725  *      Device is about to be destroyed: clean up.
1726  */
1727
1728 void ip_mc_destroy_dev(struct in_device *in_dev)
1729 {
1730         struct ip_mc_list *i;
1731
1732         ASSERT_RTNL();
1733
1734         /* Deactivate timers */
1735         ip_mc_down(in_dev);
1736 #ifdef CONFIG_IP_MULTICAST
1737         igmpv3_clear_delrec(in_dev);
1738 #endif
1739
1740         while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1741                 in_dev->mc_list = i->next_rcu;
1742                 in_dev->mc_count--;
1743                 ip_ma_put(i);
1744         }
1745 }
1746
1747 /* RTNL is locked */
1748 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1749 {
1750         struct net_device *dev = NULL;
1751         struct in_device *idev = NULL;
1752
1753         if (imr->imr_ifindex) {
1754                 idev = inetdev_by_index(net, imr->imr_ifindex);
1755                 return idev;
1756         }
1757         if (imr->imr_address.s_addr) {
1758                 dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1759                 if (!dev)
1760                         return NULL;
1761         }
1762
1763         if (!dev) {
1764                 struct rtable *rt = ip_route_output(net,
1765                                                     imr->imr_multiaddr.s_addr,
1766                                                     0, 0, 0);
1767                 if (!IS_ERR(rt)) {
1768                         dev = rt->dst.dev;
1769                         ip_rt_put(rt);
1770                 }
1771         }
1772         if (dev) {
1773                 imr->imr_ifindex = dev->ifindex;
1774                 idev = __in_dev_get_rtnl(dev);
1775         }
1776         return idev;
1777 }
1778
1779 /*
1780  *      Join a socket to a group
1781  */
1782
1783 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1784         __be32 *psfsrc)
1785 {
1786         struct ip_sf_list *psf, *psf_prev;
1787         int rv = 0;
1788
1789         psf_prev = NULL;
1790         for (psf = pmc->sources; psf; psf = psf->sf_next) {
1791                 if (psf->sf_inaddr == *psfsrc)
1792                         break;
1793                 psf_prev = psf;
1794         }
1795         if (!psf || psf->sf_count[sfmode] == 0) {
1796                 /* source filter not found, or count wrong =>  bug */
1797                 return -ESRCH;
1798         }
1799         psf->sf_count[sfmode]--;
1800         if (psf->sf_count[sfmode] == 0) {
1801                 ip_rt_multicast_event(pmc->interface);
1802         }
1803         if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1804 #ifdef CONFIG_IP_MULTICAST
1805                 struct in_device *in_dev = pmc->interface;
1806                 struct net *net = dev_net(in_dev->dev);
1807 #endif
1808
1809                 /* no more filters for this source */
1810                 if (psf_prev)
1811                         psf_prev->sf_next = psf->sf_next;
1812                 else
1813                         pmc->sources = psf->sf_next;
1814 #ifdef CONFIG_IP_MULTICAST
1815                 if (psf->sf_oldin &&
1816                     !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1817                         psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1818                         psf->sf_next = pmc->tomb;
1819                         pmc->tomb = psf;
1820                         rv = 1;
1821                 } else
1822 #endif
1823                         kfree(psf);
1824         }
1825         return rv;
1826 }
1827
1828 #ifndef CONFIG_IP_MULTICAST
1829 #define igmp_ifc_event(x)       do { } while (0)
1830 #endif
1831
1832 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1833                          int sfcount, __be32 *psfsrc, int delta)
1834 {
1835         struct ip_mc_list *pmc;
1836         int     changerec = 0;
1837         int     i, err;
1838
1839         if (!in_dev)
1840                 return -ENODEV;
1841         rcu_read_lock();
1842         for_each_pmc_rcu(in_dev, pmc) {
1843                 if (*pmca == pmc->multiaddr)
1844                         break;
1845         }
1846         if (!pmc) {
1847                 /* MCA not found?? bug */
1848                 rcu_read_unlock();
1849                 return -ESRCH;
1850         }
1851         spin_lock_bh(&pmc->lock);
1852         rcu_read_unlock();
1853 #ifdef CONFIG_IP_MULTICAST
1854         sf_markstate(pmc);
1855 #endif
1856         if (!delta) {
1857                 err = -EINVAL;
1858                 if (!pmc->sfcount[sfmode])
1859                         goto out_unlock;
1860                 pmc->sfcount[sfmode]--;
1861         }
1862         err = 0;
1863         for (i = 0; i < sfcount; i++) {
1864                 int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1865
1866                 changerec |= rv > 0;
1867                 if (!err && rv < 0)
1868                         err = rv;
1869         }
1870         if (pmc->sfmode == MCAST_EXCLUDE &&
1871             pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1872             pmc->sfcount[MCAST_INCLUDE]) {
1873 #ifdef CONFIG_IP_MULTICAST
1874                 struct ip_sf_list *psf;
1875                 struct net *net = dev_net(in_dev->dev);
1876 #endif
1877
1878                 /* filter mode change */
1879                 pmc->sfmode = MCAST_INCLUDE;
1880 #ifdef CONFIG_IP_MULTICAST
1881                 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1882                 in_dev->mr_ifc_count = pmc->crcount;
1883                 for (psf = pmc->sources; psf; psf = psf->sf_next)
1884                         psf->sf_crcount = 0;
1885                 igmp_ifc_event(pmc->interface);
1886         } else if (sf_setstate(pmc) || changerec) {
1887                 igmp_ifc_event(pmc->interface);
1888 #endif
1889         }
1890 out_unlock:
1891         spin_unlock_bh(&pmc->lock);
1892         return err;
1893 }
1894
1895 /*
1896  * Add multicast single-source filter to the interface list
1897  */
1898 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1899         __be32 *psfsrc)
1900 {
1901         struct ip_sf_list *psf, *psf_prev;
1902
1903         psf_prev = NULL;
1904         for (psf = pmc->sources; psf; psf = psf->sf_next) {
1905                 if (psf->sf_inaddr == *psfsrc)
1906                         break;
1907                 psf_prev = psf;
1908         }
1909         if (!psf) {
1910                 psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1911                 if (!psf)
1912                         return -ENOBUFS;
1913                 psf->sf_inaddr = *psfsrc;
1914                 if (psf_prev) {
1915                         psf_prev->sf_next = psf;
1916                 } else
1917                         pmc->sources = psf;
1918         }
1919         psf->sf_count[sfmode]++;
1920         if (psf->sf_count[sfmode] == 1) {
1921                 ip_rt_multicast_event(pmc->interface);
1922         }
1923         return 0;
1924 }
1925
1926 #ifdef CONFIG_IP_MULTICAST
1927 static void sf_markstate(struct ip_mc_list *pmc)
1928 {
1929         struct ip_sf_list *psf;
1930         int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1931
1932         for (psf = pmc->sources; psf; psf = psf->sf_next)
1933                 if (pmc->sfcount[MCAST_EXCLUDE]) {
1934                         psf->sf_oldin = mca_xcount ==
1935                                 psf->sf_count[MCAST_EXCLUDE] &&
1936                                 !psf->sf_count[MCAST_INCLUDE];
1937                 } else
1938                         psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1939 }
1940
1941 static int sf_setstate(struct ip_mc_list *pmc)
1942 {
1943         struct ip_sf_list *psf, *dpsf;
1944         int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1945         int qrv = pmc->interface->mr_qrv;
1946         int new_in, rv;
1947
1948         rv = 0;
1949         for (psf = pmc->sources; psf; psf = psf->sf_next) {
1950                 if (pmc->sfcount[MCAST_EXCLUDE]) {
1951                         new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1952                                 !psf->sf_count[MCAST_INCLUDE];
1953                 } else
1954                         new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1955                 if (new_in) {
1956                         if (!psf->sf_oldin) {
1957                                 struct ip_sf_list *prev = NULL;
1958
1959                                 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) {
1960                                         if (dpsf->sf_inaddr == psf->sf_inaddr)
1961                                                 break;
1962                                         prev = dpsf;
1963                                 }
1964                                 if (dpsf) {
1965                                         if (prev)
1966                                                 prev->sf_next = dpsf->sf_next;
1967                                         else
1968                                                 pmc->tomb = dpsf->sf_next;
1969                                         kfree(dpsf);
1970                                 }
1971                                 psf->sf_crcount = qrv;
1972                                 rv++;
1973                         }
1974                 } else if (psf->sf_oldin) {
1975
1976                         psf->sf_crcount = 0;
1977                         /*
1978                          * add or update "delete" records if an active filter
1979                          * is now inactive
1980                          */
1981                         for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next)
1982                                 if (dpsf->sf_inaddr == psf->sf_inaddr)
1983                                         break;
1984                         if (!dpsf) {
1985                                 dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
1986                                 if (!dpsf)
1987                                         continue;
1988                                 *dpsf = *psf;
1989                                 /* pmc->lock held by callers */
1990                                 dpsf->sf_next = pmc->tomb;
1991                                 pmc->tomb = dpsf;
1992                         }
1993                         dpsf->sf_crcount = qrv;
1994                         rv++;
1995                 }
1996         }
1997         return rv;
1998 }
1999 #endif
2000
2001 /*
2002  * Add multicast source filter list to the interface list
2003  */
2004 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
2005                          int sfcount, __be32 *psfsrc, int delta)
2006 {
2007         struct ip_mc_list *pmc;
2008         int     isexclude;
2009         int     i, err;
2010
2011         if (!in_dev)
2012                 return -ENODEV;
2013         rcu_read_lock();
2014         for_each_pmc_rcu(in_dev, pmc) {
2015                 if (*pmca == pmc->multiaddr)
2016                         break;
2017         }
2018         if (!pmc) {
2019                 /* MCA not found?? bug */
2020                 rcu_read_unlock();
2021                 return -ESRCH;
2022         }
2023         spin_lock_bh(&pmc->lock);
2024         rcu_read_unlock();
2025
2026 #ifdef CONFIG_IP_MULTICAST
2027         sf_markstate(pmc);
2028 #endif
2029         isexclude = pmc->sfmode == MCAST_EXCLUDE;
2030         if (!delta)
2031                 pmc->sfcount[sfmode]++;
2032         err = 0;
2033         for (i = 0; i < sfcount; i++) {
2034                 err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2035                 if (err)
2036                         break;
2037         }
2038         if (err) {
2039                 int j;
2040
2041                 if (!delta)
2042                         pmc->sfcount[sfmode]--;
2043                 for (j = 0; j < i; j++)
2044                         (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2045         } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
2046 #ifdef CONFIG_IP_MULTICAST
2047                 struct ip_sf_list *psf;
2048                 struct net *net = dev_net(pmc->interface->dev);
2049                 in_dev = pmc->interface;
2050 #endif
2051
2052                 /* filter mode change */
2053                 if (pmc->sfcount[MCAST_EXCLUDE])
2054                         pmc->sfmode = MCAST_EXCLUDE;
2055                 else if (pmc->sfcount[MCAST_INCLUDE])
2056                         pmc->sfmode = MCAST_INCLUDE;
2057 #ifdef CONFIG_IP_MULTICAST
2058                 /* else no filters; keep old mode for reports */
2059
2060                 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
2061                 in_dev->mr_ifc_count = pmc->crcount;
2062                 for (psf = pmc->sources; psf; psf = psf->sf_next)
2063                         psf->sf_crcount = 0;
2064                 igmp_ifc_event(in_dev);
2065         } else if (sf_setstate(pmc)) {
2066                 igmp_ifc_event(in_dev);
2067 #endif
2068         }
2069         spin_unlock_bh(&pmc->lock);
2070         return err;
2071 }
2072
2073 static void ip_mc_clear_src(struct ip_mc_list *pmc)
2074 {
2075         struct ip_sf_list *psf, *nextpsf, *tomb, *sources;
2076
2077         spin_lock_bh(&pmc->lock);
2078         tomb = pmc->tomb;
2079         pmc->tomb = NULL;
2080         sources = pmc->sources;
2081         pmc->sources = NULL;
2082         pmc->sfmode = MCAST_EXCLUDE;
2083         pmc->sfcount[MCAST_INCLUDE] = 0;
2084         pmc->sfcount[MCAST_EXCLUDE] = 1;
2085         spin_unlock_bh(&pmc->lock);
2086
2087         for (psf = tomb; psf; psf = nextpsf) {
2088                 nextpsf = psf->sf_next;
2089                 kfree(psf);
2090         }
2091         for (psf = sources; psf; psf = nextpsf) {
2092                 nextpsf = psf->sf_next;
2093                 kfree(psf);
2094         }
2095 }
2096
2097 /* Join a multicast group
2098  */
2099
2100 int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
2101 {
2102         __be32 addr = imr->imr_multiaddr.s_addr;
2103         struct ip_mc_socklist *iml, *i;
2104         struct in_device *in_dev;
2105         struct inet_sock *inet = inet_sk(sk);
2106         struct net *net = sock_net(sk);
2107         int ifindex;
2108         int count = 0;
2109         int err;
2110
2111         ASSERT_RTNL();
2112
2113         if (!ipv4_is_multicast(addr))
2114                 return -EINVAL;
2115
2116         in_dev = ip_mc_find_dev(net, imr);
2117
2118         if (!in_dev) {
2119                 err = -ENODEV;
2120                 goto done;
2121         }
2122
2123         err = -EADDRINUSE;
2124         ifindex = imr->imr_ifindex;
2125         for_each_pmc_rtnl(inet, i) {
2126                 if (i->multi.imr_multiaddr.s_addr == addr &&
2127                     i->multi.imr_ifindex == ifindex)
2128                         goto done;
2129                 count++;
2130         }
2131         err = -ENOBUFS;
2132         if (count >= net->ipv4.sysctl_igmp_max_memberships)
2133                 goto done;
2134         iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
2135         if (!iml)
2136                 goto done;
2137
2138         memcpy(&iml->multi, imr, sizeof(*imr));
2139         iml->next_rcu = inet->mc_list;
2140         iml->sflist = NULL;
2141         iml->sfmode = MCAST_EXCLUDE;
2142         rcu_assign_pointer(inet->mc_list, iml);
2143         ip_mc_inc_group(in_dev, addr);
2144         err = 0;
2145 done:
2146         return err;
2147 }
2148 EXPORT_SYMBOL(ip_mc_join_group);
2149
2150 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
2151                            struct in_device *in_dev)
2152 {
2153         struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
2154         int err;
2155
2156         if (!psf) {
2157                 /* any-source empty exclude case */
2158                 return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2159                         iml->sfmode, 0, NULL, 0);
2160         }
2161         err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2162                         iml->sfmode, psf->sl_count, psf->sl_addr, 0);
2163         RCU_INIT_POINTER(iml->sflist, NULL);
2164         /* decrease mem now to avoid the memleak warning */
2165         atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc);
2166         kfree_rcu(psf, rcu);
2167         return err;
2168 }
2169
2170 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
2171 {
2172         struct inet_sock *inet = inet_sk(sk);
2173         struct ip_mc_socklist *iml;
2174         struct ip_mc_socklist __rcu **imlp;
2175         struct in_device *in_dev;
2176         struct net *net = sock_net(sk);
2177         __be32 group = imr->imr_multiaddr.s_addr;
2178         u32 ifindex;
2179         int ret = -EADDRNOTAVAIL;
2180
2181         ASSERT_RTNL();
2182
2183         in_dev = ip_mc_find_dev(net, imr);
2184         if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) {
2185                 ret = -ENODEV;
2186                 goto out;
2187         }
2188         ifindex = imr->imr_ifindex;
2189         for (imlp = &inet->mc_list;
2190              (iml = rtnl_dereference(*imlp)) != NULL;
2191              imlp = &iml->next_rcu) {
2192                 if (iml->multi.imr_multiaddr.s_addr != group)
2193                         continue;
2194                 if (ifindex) {
2195                         if (iml->multi.imr_ifindex != ifindex)
2196                                 continue;
2197                 } else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
2198                                 iml->multi.imr_address.s_addr)
2199                         continue;
2200
2201                 (void) ip_mc_leave_src(sk, iml, in_dev);
2202
2203                 *imlp = iml->next_rcu;
2204
2205                 if (in_dev)
2206                         ip_mc_dec_group(in_dev, group);
2207
2208                 /* decrease mem now to avoid the memleak warning */
2209                 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2210                 kfree_rcu(iml, rcu);
2211                 return 0;
2212         }
2213 out:
2214         return ret;
2215 }
2216 EXPORT_SYMBOL(ip_mc_leave_group);
2217
2218 int ip_mc_source(int add, int omode, struct sock *sk, struct
2219         ip_mreq_source *mreqs, int ifindex)
2220 {
2221         int err;
2222         struct ip_mreqn imr;
2223         __be32 addr = mreqs->imr_multiaddr;
2224         struct ip_mc_socklist *pmc;
2225         struct in_device *in_dev = NULL;
2226         struct inet_sock *inet = inet_sk(sk);
2227         struct ip_sf_socklist *psl;
2228         struct net *net = sock_net(sk);
2229         int leavegroup = 0;
2230         int i, j, rv;
2231
2232         if (!ipv4_is_multicast(addr))
2233                 return -EINVAL;
2234
2235         ASSERT_RTNL();
2236
2237         imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
2238         imr.imr_address.s_addr = mreqs->imr_interface;
2239         imr.imr_ifindex = ifindex;
2240         in_dev = ip_mc_find_dev(net, &imr);
2241
2242         if (!in_dev) {
2243                 err = -ENODEV;
2244                 goto done;
2245         }
2246         err = -EADDRNOTAVAIL;
2247
2248         for_each_pmc_rtnl(inet, pmc) {
2249                 if ((pmc->multi.imr_multiaddr.s_addr ==
2250                      imr.imr_multiaddr.s_addr) &&
2251                     (pmc->multi.imr_ifindex == imr.imr_ifindex))
2252                         break;
2253         }
2254         if (!pmc) {             /* must have a prior join */
2255                 err = -EINVAL;
2256                 goto done;
2257         }
2258         /* if a source filter was set, must be the same mode as before */
2259         if (pmc->sflist) {
2260                 if (pmc->sfmode != omode) {
2261                         err = -EINVAL;
2262                         goto done;
2263                 }
2264         } else if (pmc->sfmode != omode) {
2265                 /* allow mode switches for empty-set filters */
2266                 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
2267                 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
2268                         NULL, 0);
2269                 pmc->sfmode = omode;
2270         }
2271
2272         psl = rtnl_dereference(pmc->sflist);
2273         if (!add) {
2274                 if (!psl)
2275                         goto done;      /* err = -EADDRNOTAVAIL */
2276                 rv = !0;
2277                 for (i = 0; i < psl->sl_count; i++) {
2278                         rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2279                                 sizeof(__be32));
2280                         if (rv == 0)
2281                                 break;
2282                 }
2283                 if (rv)         /* source not found */
2284                         goto done;      /* err = -EADDRNOTAVAIL */
2285
2286                 /* special case - (INCLUDE, empty) == LEAVE_GROUP */
2287                 if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
2288                         leavegroup = 1;
2289                         goto done;
2290                 }
2291
2292                 /* update the interface filter */
2293                 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2294                         &mreqs->imr_sourceaddr, 1);
2295
2296                 for (j = i+1; j < psl->sl_count; j++)
2297                         psl->sl_addr[j-1] = psl->sl_addr[j];
2298                 psl->sl_count--;
2299                 err = 0;
2300                 goto done;
2301         }
2302         /* else, add a new source to the filter */
2303
2304         if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) {
2305                 err = -ENOBUFS;
2306                 goto done;
2307         }
2308         if (!psl || psl->sl_count == psl->sl_max) {
2309                 struct ip_sf_socklist *newpsl;
2310                 int count = IP_SFBLOCK;
2311
2312                 if (psl)
2313                         count += psl->sl_max;
2314                 newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
2315                 if (!newpsl) {
2316                         err = -ENOBUFS;
2317                         goto done;
2318                 }
2319                 newpsl->sl_max = count;
2320                 newpsl->sl_count = count - IP_SFBLOCK;
2321                 if (psl) {
2322                         for (i = 0; i < psl->sl_count; i++)
2323                                 newpsl->sl_addr[i] = psl->sl_addr[i];
2324                         /* decrease mem now to avoid the memleak warning */
2325                         atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2326                         kfree_rcu(psl, rcu);
2327                 }
2328                 rcu_assign_pointer(pmc->sflist, newpsl);
2329                 psl = newpsl;
2330         }
2331         rv = 1; /* > 0 for insert logic below if sl_count is 0 */
2332         for (i = 0; i < psl->sl_count; i++) {
2333                 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2334                         sizeof(__be32));
2335                 if (rv == 0)
2336                         break;
2337         }
2338         if (rv == 0)            /* address already there is an error */
2339                 goto done;
2340         for (j = psl->sl_count-1; j >= i; j--)
2341                 psl->sl_addr[j+1] = psl->sl_addr[j];
2342         psl->sl_addr[i] = mreqs->imr_sourceaddr;
2343         psl->sl_count++;
2344         err = 0;
2345         /* update the interface list */
2346         ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2347                 &mreqs->imr_sourceaddr, 1);
2348 done:
2349         if (leavegroup)
2350                 err = ip_mc_leave_group(sk, &imr);
2351         return err;
2352 }
2353
2354 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2355 {
2356         int err = 0;
2357         struct ip_mreqn imr;
2358         __be32 addr = msf->imsf_multiaddr;
2359         struct ip_mc_socklist *pmc;
2360         struct in_device *in_dev;
2361         struct inet_sock *inet = inet_sk(sk);
2362         struct ip_sf_socklist *newpsl, *psl;
2363         struct net *net = sock_net(sk);
2364         int leavegroup = 0;
2365
2366         if (!ipv4_is_multicast(addr))
2367                 return -EINVAL;
2368         if (msf->imsf_fmode != MCAST_INCLUDE &&
2369             msf->imsf_fmode != MCAST_EXCLUDE)
2370                 return -EINVAL;
2371
2372         ASSERT_RTNL();
2373
2374         imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2375         imr.imr_address.s_addr = msf->imsf_interface;
2376         imr.imr_ifindex = ifindex;
2377         in_dev = ip_mc_find_dev(net, &imr);
2378
2379         if (!in_dev) {
2380                 err = -ENODEV;
2381                 goto done;
2382         }
2383
2384         /* special case - (INCLUDE, empty) == LEAVE_GROUP */
2385         if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2386                 leavegroup = 1;
2387                 goto done;
2388         }
2389
2390         for_each_pmc_rtnl(inet, pmc) {
2391                 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2392                     pmc->multi.imr_ifindex == imr.imr_ifindex)
2393                         break;
2394         }
2395         if (!pmc) {             /* must have a prior join */
2396                 err = -EINVAL;
2397                 goto done;
2398         }
2399         if (msf->imsf_numsrc) {
2400                 newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2401                                                            GFP_KERNEL);
2402                 if (!newpsl) {
2403                         err = -ENOBUFS;
2404                         goto done;
2405                 }
2406                 newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2407                 memcpy(newpsl->sl_addr, msf->imsf_slist,
2408                         msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2409                 err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2410                         msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2411                 if (err) {
2412                         sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2413                         goto done;
2414                 }
2415         } else {
2416                 newpsl = NULL;
2417                 (void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2418                                      msf->imsf_fmode, 0, NULL, 0);
2419         }
2420         psl = rtnl_dereference(pmc->sflist);
2421         if (psl) {
2422                 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2423                         psl->sl_count, psl->sl_addr, 0);
2424                 /* decrease mem now to avoid the memleak warning */
2425                 atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2426                 kfree_rcu(psl, rcu);
2427         } else
2428                 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2429                         0, NULL, 0);
2430         rcu_assign_pointer(pmc->sflist, newpsl);
2431         pmc->sfmode = msf->imsf_fmode;
2432         err = 0;
2433 done:
2434         if (leavegroup)
2435                 err = ip_mc_leave_group(sk, &imr);
2436         return err;
2437 }
2438
2439 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2440         struct ip_msfilter __user *optval, int __user *optlen)
2441 {
2442         int err, len, count, copycount;
2443         struct ip_mreqn imr;
2444         __be32 addr = msf->imsf_multiaddr;
2445         struct ip_mc_socklist *pmc;
2446         struct in_device *in_dev;
2447         struct inet_sock *inet = inet_sk(sk);
2448         struct ip_sf_socklist *psl;
2449         struct net *net = sock_net(sk);
2450
2451         ASSERT_RTNL();
2452
2453         if (!ipv4_is_multicast(addr))
2454                 return -EINVAL;
2455
2456         imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2457         imr.imr_address.s_addr = msf->imsf_interface;
2458         imr.imr_ifindex = 0;
2459         in_dev = ip_mc_find_dev(net, &imr);
2460
2461         if (!in_dev) {
2462                 err = -ENODEV;
2463                 goto done;
2464         }
2465         err = -EADDRNOTAVAIL;
2466
2467         for_each_pmc_rtnl(inet, pmc) {
2468                 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2469                     pmc->multi.imr_ifindex == imr.imr_ifindex)
2470                         break;
2471         }
2472         if (!pmc)               /* must have a prior join */
2473                 goto done;
2474         msf->imsf_fmode = pmc->sfmode;
2475         psl = rtnl_dereference(pmc->sflist);
2476         if (!psl) {
2477                 len = 0;
2478                 count = 0;
2479         } else {
2480                 count = psl->sl_count;
2481         }
2482         copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2483         len = copycount * sizeof(psl->sl_addr[0]);
2484         msf->imsf_numsrc = count;
2485         if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2486             copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2487                 return -EFAULT;
2488         }
2489         if (len &&
2490             copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2491                 return -EFAULT;
2492         return 0;
2493 done:
2494         return err;
2495 }
2496
2497 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2498         struct group_filter __user *optval, int __user *optlen)
2499 {
2500         int err, i, count, copycount;
2501         struct sockaddr_in *psin;
2502         __be32 addr;
2503         struct ip_mc_socklist *pmc;
2504         struct inet_sock *inet = inet_sk(sk);
2505         struct ip_sf_socklist *psl;
2506
2507         ASSERT_RTNL();
2508
2509         psin = (struct sockaddr_in *)&gsf->gf_group;
2510         if (psin->sin_family != AF_INET)
2511                 return -EINVAL;
2512         addr = psin->sin_addr.s_addr;
2513         if (!ipv4_is_multicast(addr))
2514                 return -EINVAL;
2515
2516         err = -EADDRNOTAVAIL;
2517
2518         for_each_pmc_rtnl(inet, pmc) {
2519                 if (pmc->multi.imr_multiaddr.s_addr == addr &&
2520                     pmc->multi.imr_ifindex == gsf->gf_interface)
2521                         break;
2522         }
2523         if (!pmc)               /* must have a prior join */
2524                 goto done;
2525         gsf->gf_fmode = pmc->sfmode;
2526         psl = rtnl_dereference(pmc->sflist);
2527         count = psl ? psl->sl_count : 0;
2528         copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2529         gsf->gf_numsrc = count;
2530         if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2531             copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2532                 return -EFAULT;
2533         }
2534         for (i = 0; i < copycount; i++) {
2535                 struct sockaddr_storage ss;
2536
2537                 psin = (struct sockaddr_in *)&ss;
2538                 memset(&ss, 0, sizeof(ss));
2539                 psin->sin_family = AF_INET;
2540                 psin->sin_addr.s_addr = psl->sl_addr[i];
2541                 if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2542                         return -EFAULT;
2543         }
2544         return 0;
2545 done:
2546         return err;
2547 }
2548
2549 /*
2550  * check if a multicast source filter allows delivery for a given <src,dst,intf>
2551  */
2552 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif)
2553 {
2554         struct inet_sock *inet = inet_sk(sk);
2555         struct ip_mc_socklist *pmc;
2556         struct ip_sf_socklist *psl;
2557         int i;
2558         int ret;
2559
2560         ret = 1;
2561         if (!ipv4_is_multicast(loc_addr))
2562                 goto out;
2563
2564         rcu_read_lock();
2565         for_each_pmc_rcu(inet, pmc) {
2566                 if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2567                     pmc->multi.imr_ifindex == dif)
2568                         break;
2569         }
2570         ret = inet->mc_all;
2571         if (!pmc)
2572                 goto unlock;
2573         psl = rcu_dereference(pmc->sflist);
2574         ret = (pmc->sfmode == MCAST_EXCLUDE);
2575         if (!psl)
2576                 goto unlock;
2577
2578         for (i = 0; i < psl->sl_count; i++) {
2579                 if (psl->sl_addr[i] == rmt_addr)
2580                         break;
2581         }
2582         ret = 0;
2583         if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2584                 goto unlock;
2585         if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2586                 goto unlock;
2587         ret = 1;
2588 unlock:
2589         rcu_read_unlock();
2590 out:
2591         return ret;
2592 }
2593
2594 /*
2595  *      A socket is closing.
2596  */
2597
2598 void ip_mc_drop_socket(struct sock *sk)
2599 {
2600         struct inet_sock *inet = inet_sk(sk);
2601         struct ip_mc_socklist *iml;
2602         struct net *net = sock_net(sk);
2603
2604         if (!inet->mc_list)
2605                 return;
2606
2607         rtnl_lock();
2608         while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2609                 struct in_device *in_dev;
2610
2611                 inet->mc_list = iml->next_rcu;
2612                 in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2613                 (void) ip_mc_leave_src(sk, iml, in_dev);
2614                 if (in_dev)
2615                         ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2616                 /* decrease mem now to avoid the memleak warning */
2617                 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2618                 kfree_rcu(iml, rcu);
2619         }
2620         rtnl_unlock();
2621 }
2622
2623 /* called with rcu_read_lock() */
2624 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto)
2625 {
2626         struct ip_mc_list *im;
2627         struct ip_mc_list __rcu **mc_hash;
2628         struct ip_sf_list *psf;
2629         int rv = 0;
2630
2631         mc_hash = rcu_dereference(in_dev->mc_hash);
2632         if (mc_hash) {
2633                 u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
2634
2635                 for (im = rcu_dereference(mc_hash[hash]);
2636                      im != NULL;
2637                      im = rcu_dereference(im->next_hash)) {
2638                         if (im->multiaddr == mc_addr)
2639                                 break;
2640                 }
2641         } else {
2642                 for_each_pmc_rcu(in_dev, im) {
2643                         if (im->multiaddr == mc_addr)
2644                                 break;
2645                 }
2646         }
2647         if (im && proto == IPPROTO_IGMP) {
2648                 rv = 1;
2649         } else if (im) {
2650                 if (src_addr) {
2651                         for (psf = im->sources; psf; psf = psf->sf_next) {
2652                                 if (psf->sf_inaddr == src_addr)
2653                                         break;
2654                         }
2655                         if (psf)
2656                                 rv = psf->sf_count[MCAST_INCLUDE] ||
2657                                         psf->sf_count[MCAST_EXCLUDE] !=
2658                                         im->sfcount[MCAST_EXCLUDE];
2659                         else
2660                                 rv = im->sfcount[MCAST_EXCLUDE] != 0;
2661                 } else
2662                         rv = 1; /* unspecified source; tentatively allow */
2663         }
2664         return rv;
2665 }
2666
2667 #if defined(CONFIG_PROC_FS)
2668 struct igmp_mc_iter_state {
2669         struct seq_net_private p;
2670         struct net_device *dev;
2671         struct in_device *in_dev;
2672 };
2673
2674 #define igmp_mc_seq_private(seq)        ((struct igmp_mc_iter_state *)(seq)->private)
2675
2676 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2677 {
2678         struct net *net = seq_file_net(seq);
2679         struct ip_mc_list *im = NULL;
2680         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2681
2682         state->in_dev = NULL;
2683         for_each_netdev_rcu(net, state->dev) {
2684                 struct in_device *in_dev;
2685
2686                 in_dev = __in_dev_get_rcu(state->dev);
2687                 if (!in_dev)
2688                         continue;
2689                 im = rcu_dereference(in_dev->mc_list);
2690                 if (im) {
2691                         state->in_dev = in_dev;
2692                         break;
2693                 }
2694         }
2695         return im;
2696 }
2697
2698 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2699 {
2700         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2701
2702         im = rcu_dereference(im->next_rcu);
2703         while (!im) {
2704                 state->dev = next_net_device_rcu(state->dev);
2705                 if (!state->dev) {
2706                         state->in_dev = NULL;
2707                         break;
2708                 }
2709                 state->in_dev = __in_dev_get_rcu(state->dev);
2710                 if (!state->in_dev)
2711                         continue;
2712                 im = rcu_dereference(state->in_dev->mc_list);
2713         }
2714         return im;
2715 }
2716
2717 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2718 {
2719         struct ip_mc_list *im = igmp_mc_get_first(seq);
2720         if (im)
2721                 while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2722                         --pos;
2723         return pos ? NULL : im;
2724 }
2725
2726 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2727         __acquires(rcu)
2728 {
2729         rcu_read_lock();
2730         return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2731 }
2732
2733 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2734 {
2735         struct ip_mc_list *im;
2736         if (v == SEQ_START_TOKEN)
2737                 im = igmp_mc_get_first(seq);
2738         else
2739                 im = igmp_mc_get_next(seq, v);
2740         ++*pos;
2741         return im;
2742 }
2743
2744 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2745         __releases(rcu)
2746 {
2747         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2748
2749         state->in_dev = NULL;
2750         state->dev = NULL;
2751         rcu_read_unlock();
2752 }
2753
2754 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2755 {
2756         if (v == SEQ_START_TOKEN)
2757                 seq_puts(seq,
2758                          "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2759         else {
2760                 struct ip_mc_list *im = (struct ip_mc_list *)v;
2761                 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2762                 char   *querier;
2763                 long delta;
2764
2765 #ifdef CONFIG_IP_MULTICAST
2766                 querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2767                           IGMP_V2_SEEN(state->in_dev) ? "V2" :
2768                           "V3";
2769 #else
2770                 querier = "NONE";
2771 #endif
2772
2773                 if (rcu_access_pointer(state->in_dev->mc_list) == im) {
2774                         seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2775                                    state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2776                 }
2777
2778                 delta = im->timer.expires - jiffies;
2779                 seq_printf(seq,
2780                            "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2781                            im->multiaddr, im->users,
2782                            im->tm_running,
2783                            im->tm_running ? jiffies_delta_to_clock_t(delta) : 0,
2784                            im->reporter);
2785         }
2786         return 0;
2787 }
2788
2789 static const struct seq_operations igmp_mc_seq_ops = {
2790         .start  =       igmp_mc_seq_start,
2791         .next   =       igmp_mc_seq_next,
2792         .stop   =       igmp_mc_seq_stop,
2793         .show   =       igmp_mc_seq_show,
2794 };
2795
2796 static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2797 {
2798         return seq_open_net(inode, file, &igmp_mc_seq_ops,
2799                         sizeof(struct igmp_mc_iter_state));
2800 }
2801
2802 static const struct file_operations igmp_mc_seq_fops = {
2803         .owner          =       THIS_MODULE,
2804         .open           =       igmp_mc_seq_open,
2805         .read           =       seq_read,
2806         .llseek         =       seq_lseek,
2807         .release        =       seq_release_net,
2808 };
2809
2810 struct igmp_mcf_iter_state {
2811         struct seq_net_private p;
2812         struct net_device *dev;
2813         struct in_device *idev;
2814         struct ip_mc_list *im;
2815 };
2816
2817 #define igmp_mcf_seq_private(seq)       ((struct igmp_mcf_iter_state *)(seq)->private)
2818
2819 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2820 {
2821         struct net *net = seq_file_net(seq);
2822         struct ip_sf_list *psf = NULL;
2823         struct ip_mc_list *im = NULL;
2824         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2825
2826         state->idev = NULL;
2827         state->im = NULL;
2828         for_each_netdev_rcu(net, state->dev) {
2829                 struct in_device *idev;
2830                 idev = __in_dev_get_rcu(state->dev);
2831                 if (unlikely(!idev))
2832                         continue;
2833                 im = rcu_dereference(idev->mc_list);
2834                 if (likely(im)) {
2835                         spin_lock_bh(&im->lock);
2836                         psf = im->sources;
2837                         if (likely(psf)) {
2838                                 state->im = im;
2839                                 state->idev = idev;
2840                                 break;
2841                         }
2842                         spin_unlock_bh(&im->lock);
2843                 }
2844         }
2845         return psf;
2846 }
2847
2848 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2849 {
2850         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2851
2852         psf = psf->sf_next;
2853         while (!psf) {
2854                 spin_unlock_bh(&state->im->lock);
2855                 state->im = state->im->next;
2856                 while (!state->im) {
2857                         state->dev = next_net_device_rcu(state->dev);
2858                         if (!state->dev) {
2859                                 state->idev = NULL;
2860                                 goto out;
2861                         }
2862                         state->idev = __in_dev_get_rcu(state->dev);
2863                         if (!state->idev)
2864                                 continue;
2865                         state->im = rcu_dereference(state->idev->mc_list);
2866                 }
2867                 if (!state->im)
2868                         break;
2869                 spin_lock_bh(&state->im->lock);
2870                 psf = state->im->sources;
2871         }
2872 out:
2873         return psf;
2874 }
2875
2876 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2877 {
2878         struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2879         if (psf)
2880                 while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2881                         --pos;
2882         return pos ? NULL : psf;
2883 }
2884
2885 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2886         __acquires(rcu)
2887 {
2888         rcu_read_lock();
2889         return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2890 }
2891
2892 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2893 {
2894         struct ip_sf_list *psf;
2895         if (v == SEQ_START_TOKEN)
2896                 psf = igmp_mcf_get_first(seq);
2897         else
2898                 psf = igmp_mcf_get_next(seq, v);
2899         ++*pos;
2900         return psf;
2901 }
2902
2903 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2904         __releases(rcu)
2905 {
2906         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2907         if (likely(state->im)) {
2908                 spin_unlock_bh(&state->im->lock);
2909                 state->im = NULL;
2910         }
2911         state->idev = NULL;
2912         state->dev = NULL;
2913         rcu_read_unlock();
2914 }
2915
2916 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2917 {
2918         struct ip_sf_list *psf = (struct ip_sf_list *)v;
2919         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2920
2921         if (v == SEQ_START_TOKEN) {
2922                 seq_puts(seq, "Idx Device        MCA        SRC    INC    EXC\n");
2923         } else {
2924                 seq_printf(seq,
2925                            "%3d %6.6s 0x%08x "
2926                            "0x%08x %6lu %6lu\n",
2927                            state->dev->ifindex, state->dev->name,
2928                            ntohl(state->im->multiaddr),
2929                            ntohl(psf->sf_inaddr),
2930                            psf->sf_count[MCAST_INCLUDE],
2931                            psf->sf_count[MCAST_EXCLUDE]);
2932         }
2933         return 0;
2934 }
2935
2936 static const struct seq_operations igmp_mcf_seq_ops = {
2937         .start  =       igmp_mcf_seq_start,
2938         .next   =       igmp_mcf_seq_next,
2939         .stop   =       igmp_mcf_seq_stop,
2940         .show   =       igmp_mcf_seq_show,
2941 };
2942
2943 static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2944 {
2945         return seq_open_net(inode, file, &igmp_mcf_seq_ops,
2946                         sizeof(struct igmp_mcf_iter_state));
2947 }
2948
2949 static const struct file_operations igmp_mcf_seq_fops = {
2950         .owner          =       THIS_MODULE,
2951         .open           =       igmp_mcf_seq_open,
2952         .read           =       seq_read,
2953         .llseek         =       seq_lseek,
2954         .release        =       seq_release_net,
2955 };
2956
2957 static int __net_init igmp_net_init(struct net *net)
2958 {
2959         struct proc_dir_entry *pde;
2960         int err;
2961
2962         pde = proc_create("igmp", S_IRUGO, net->proc_net, &igmp_mc_seq_fops);
2963         if (!pde)
2964                 goto out_igmp;
2965         pde = proc_create("mcfilter", S_IRUGO, net->proc_net,
2966                           &igmp_mcf_seq_fops);
2967         if (!pde)
2968                 goto out_mcfilter;
2969         err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET,
2970                                    SOCK_DGRAM, 0, net);
2971         if (err < 0) {
2972                 pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n",
2973                        err);
2974                 goto out_sock;
2975         }
2976
2977         /* Sysctl initialization */
2978         net->ipv4.sysctl_igmp_max_memberships = 20;
2979         net->ipv4.sysctl_igmp_max_msf = 10;
2980         /* IGMP reports for link-local multicast groups are enabled by default */
2981         net->ipv4.sysctl_igmp_llm_reports = 1;
2982         net->ipv4.sysctl_igmp_qrv = 2;
2983         return 0;
2984
2985 out_sock:
2986         remove_proc_entry("mcfilter", net->proc_net);
2987 out_mcfilter:
2988         remove_proc_entry("igmp", net->proc_net);
2989 out_igmp:
2990         return -ENOMEM;
2991 }
2992
2993 static void __net_exit igmp_net_exit(struct net *net)
2994 {
2995         remove_proc_entry("mcfilter", net->proc_net);
2996         remove_proc_entry("igmp", net->proc_net);
2997         inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk);
2998 }
2999
3000 static struct pernet_operations igmp_net_ops = {
3001         .init = igmp_net_init,
3002         .exit = igmp_net_exit,
3003 };
3004 #endif
3005
3006 static int igmp_netdev_event(struct notifier_block *this,
3007                              unsigned long event, void *ptr)
3008 {
3009         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3010         struct in_device *in_dev;
3011
3012         switch (event) {
3013         case NETDEV_RESEND_IGMP:
3014                 in_dev = __in_dev_get_rtnl(dev);
3015                 if (in_dev)
3016                         ip_mc_rejoin_groups(in_dev);
3017                 break;
3018         default:
3019                 break;
3020         }
3021         return NOTIFY_DONE;
3022 }
3023
3024 static struct notifier_block igmp_notifier = {
3025         .notifier_call = igmp_netdev_event,
3026 };
3027
3028 int __init igmp_mc_init(void)
3029 {
3030 #if defined(CONFIG_PROC_FS)
3031         int err;
3032
3033         err = register_pernet_subsys(&igmp_net_ops);
3034         if (err)
3035                 return err;
3036         err = register_netdevice_notifier(&igmp_notifier);
3037         if (err)
3038                 goto reg_notif_fail;
3039         return 0;
3040
3041 reg_notif_fail:
3042         unregister_pernet_subsys(&igmp_net_ops);
3043         return err;
3044 #else
3045         return register_netdevice_notifier(&igmp_notifier);
3046 #endif
3047 }