net/ipv4/igmp.c

   1 /*
   2  *      Linux NET3:     Internet Group Management Protocol  [IGMP]
   3  *
   4  *      This code implements the IGMP protocol as defined in RFC1112. There has
   5  *      been a further revision of this protocol since which is now supported.
   6  *
   7  *      If you have trouble with this module be careful what gcc you have used,
   8  *      the older version didn't come out right using gcc 2.5.8, the newer one
   9  *      seems to fall out with gcc 2.6.2.
  10  *
  11  *      Authors:
  12  *              Alan Cox <alan@lxorguk.ukuu.org.uk>
  13  *
  14  *      This program is free software; you can redistribute it and/or
  15  *      modify it under the terms of the GNU General Public License
  16  *      as published by the Free Software Foundation; either version
  17  *      2 of the License, or (at your option) any later version.
  18  *
  19  *      Fixes:
  20  *
  21  *              Alan Cox        :       Added lots of __inline__ to optimise
  22  *                                      the memory usage of all the tiny little
  23  *                                      functions.
  24  *              Alan Cox        :       Dumped the header building experiment.
  25  *              Alan Cox        :       Minor tweaks ready for multicast routing
  26  *                                      and extended IGMP protocol.
  27  *              Alan Cox        :       Removed a load of inline directives. Gcc 2.5.8
  28  *                                      writes utterly bogus code otherwise (sigh)
  29  *                                      fixed IGMP loopback to behave in the manner
  30  *                                      desired by mrouted, fixed the fact it has been
  31  *                                      broken since 1.3.6 and cleaned up a few minor
  32  *                                      points.
  33  *
  34  *              Chih-Jen Chang  :       Tried to revise IGMP to Version 2
  35  *              Tsu-Sheng Tsao          E-mail: chihjenc@scf.usc.edu and tsusheng@scf.usc.edu
  36  *                                      The enhancements are mainly based on Steve Deering's
  37  *                                      ipmulti-3.5 source code.
  38  *              Chih-Jen Chang  :       Added the igmp_get_mrouter_info and
  39  *              Tsu-Sheng Tsao          igmp_set_mrouter_info to keep track of
  40  *                                      the mrouted version on that device.
  41  *              Chih-Jen Chang  :       Added the max_resp_time parameter to
  42  *              Tsu-Sheng Tsao          igmp_heard_query(). Using this parameter
  43  *                                      to identify the multicast router version
  44  *                                      and do what the IGMP version 2 specified.
  45  *              Chih-Jen Chang  :       Added a timer to revert to IGMP V2 router
  46  *              Tsu-Sheng Tsao          if the specified time expired.
  47  *              Alan Cox        :       Stop IGMP from 0.0.0.0 being accepted.
  48  *              Alan Cox        :       Use GFP_ATOMIC in the right places.
  49  *              Christian Daudt :       igmp timer wasn't set for local group
  50  *                                      memberships but was being deleted,
  51  *                                      which caused a "del_timer() called
  52  *                                      from %p with timer not initialized\n"
  53  *                                      message (960131).
  54  *              Christian Daudt :       removed del_timer from
  55  *                                      igmp_timer_expire function (960205).
  56  *             Christian Daudt :       igmp_heard_report now only calls
  57  *                                     igmp_timer_expire if tm->running is
  58  *                                     true (960216).
  59  *              Malcolm Beattie :       ttl comparison wrong in igmp_rcv made
  60  *                                      igmp_heard_query never trigger. Expiry
  61  *                                      miscalculation fixed in igmp_heard_query
  62  *                                      and random() made to return unsigned to
  63  *                                      prevent negative expiry times.
  64  *              Alexey Kuznetsov:       Wrong group leaving behaviour, backport
  65  *                                      fix from pending 2.1.x patches.
  66  *              Alan Cox:               Forget to enable FDDI support earlier.
  67  *              Alexey Kuznetsov:       Fixed leaving groups on device down.
  68  *              Alexey Kuznetsov:       Accordance to igmp-v2-06 draft.
  69  *              David L Stevens:        IGMPv3 support, with help from
  70  *                                      Vinay Kulkarni
  71  */
  72
  73 #include <linux/module.h>
  74 #include <linux/slab.h>
  75 #include <asm/uaccess.h>
  76 #include <linux/types.h>
  77 #include <linux/kernel.h>
  78 #include <linux/jiffies.h>
  79 #include <linux/string.h>
  80 #include <linux/socket.h>
  81 #include <linux/sockios.h>
  82 #include <linux/in.h>
  83 #include <linux/inet.h>
  84 #include <linux/netdevice.h>
  85 #include <linux/skbuff.h>
  86 #include <linux/inetdevice.h>
  87 #include <linux/igmp.h>
  88 #include <linux/if_arp.h>
  89 #include <linux/rtnetlink.h>
  90 #include <linux/times.h>
  91 #include <linux/pkt_sched.h>
  92
  93 #include <net/net_namespace.h>
  94 #include <net/arp.h>
  95 #include <net/ip.h>
  96 #include <net/protocol.h>
  97 #include <net/route.h>
  98 #include <net/sock.h>
  99 #include <net/checksum.h>
 100 #include <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, __be32 multiaddr);
 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
 223         in_dev->mr_gq_running = 1;
 224         if (!mod_timer(&in_dev->mr_gq_timer, jiffies+tv+2))
 225                 in_dev_hold(in_dev);
 226 }
 227
 228 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
 229 {
 230         int tv = prandom_u32() % delay;
 231
 232         if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
 233                 in_dev_hold(in_dev);
 234 }
 235
 236 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
 237 {
 238         spin_lock_bh(&im->lock);
 239         im->unsolicit_count = 0;
 240         if (del_timer(&im->timer)) {
 241                 if ((long)(im->timer.expires-jiffies) < max_delay) {
 242                         add_timer(&im->timer);
 243                         im->tm_running = 1;
 244                         spin_unlock_bh(&im->lock);
 245                         return;
 246                 }
 247                 atomic_dec(&im->refcnt);
 248         }
 249         igmp_start_timer(im, max_delay);
 250         spin_unlock_bh(&im->lock);
 251 }
 252
 253
 254 /*
 255  *      Send an IGMP report.
 256  */
 257
 258 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
 259
 260
 261 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
 262         int gdeleted, int sdeleted)
 263 {
 264         switch (type) {
 265         case IGMPV3_MODE_IS_INCLUDE:
 266         case IGMPV3_MODE_IS_EXCLUDE:
 267                 if (gdeleted || sdeleted)
 268                         return 0;
 269                 if (!(pmc->gsquery && !psf->sf_gsresp)) {
 270                         if (pmc->sfmode == MCAST_INCLUDE)
 271                                 return 1;
 272                         /* don't include if this source is excluded
 273                          * in all filters
 274                          */
 275                         if (psf->sf_count[MCAST_INCLUDE])
 276                                 return type == IGMPV3_MODE_IS_INCLUDE;
 277                         return pmc->sfcount[MCAST_EXCLUDE] ==
 278                                 psf->sf_count[MCAST_EXCLUDE];
 279                 }
 280                 return 0;
 281         case IGMPV3_CHANGE_TO_INCLUDE:
 282                 if (gdeleted || sdeleted)
 283                         return 0;
 284                 return psf->sf_count[MCAST_INCLUDE] != 0;
 285         case IGMPV3_CHANGE_TO_EXCLUDE:
 286                 if (gdeleted || sdeleted)
 287                         return 0;
 288                 if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
 289                     psf->sf_count[MCAST_INCLUDE])
 290                         return 0;
 291                 return pmc->sfcount[MCAST_EXCLUDE] ==
 292                         psf->sf_count[MCAST_EXCLUDE];
 293         case IGMPV3_ALLOW_NEW_SOURCES:
 294                 if (gdeleted || !psf->sf_crcount)
 295                         return 0;
 296                 return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
 297         case IGMPV3_BLOCK_OLD_SOURCES:
 298                 if (pmc->sfmode == MCAST_INCLUDE)
 299                         return gdeleted || (psf->sf_crcount && sdeleted);
 300                 return psf->sf_crcount && !gdeleted && !sdeleted;
 301         }
 302         return 0;
 303 }
 304
 305 static int
 306 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
 307 {
 308         struct ip_sf_list *psf;
 309         int scount = 0;
 310
 311         for (psf = pmc->sources; psf; psf = psf->sf_next) {
 312                 if (!is_in(pmc, psf, type, gdeleted, sdeleted))
 313                         continue;
 314                 scount++;
 315         }
 316         return scount;
 317 }
 318
 319 static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
 320 {
 321         struct sk_buff *skb;
 322         struct rtable *rt;
 323         struct iphdr *pip;
 324         struct igmpv3_report *pig;
 325         struct net *net = dev_net(dev);
 326         struct flowi4 fl4;
 327         int hlen = LL_RESERVED_SPACE(dev);
 328         int tlen = dev->needed_tailroom;
 329         unsigned int size = mtu;
 330
 331         while (1) {
 332                 skb = alloc_skb(size + hlen + tlen,
 333                                 GFP_ATOMIC | __GFP_NOWARN);
 334                 if (skb)
 335                         break;
 336                 size >>= 1;
 337                 if (size < 256)
 338                         return NULL;
 339         }
 340         skb->priority = TC_PRIO_CONTROL;
 341
 342         rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0,
 343                                    0, 0,
 344                                    IPPROTO_IGMP, 0, dev->ifindex);
 345         if (IS_ERR(rt)) {
 346                 kfree_skb(skb);
 347                 return NULL;
 348         }
 349
 350         skb_dst_set(skb, &rt->dst);
 351         skb->dev = dev;
 352
 353         skb_reserve(skb, hlen);
 354         skb_tailroom_reserve(skb, mtu, tlen);
 355
 356         skb_reset_network_header(skb);
 357         pip = ip_hdr(skb);
 358         skb_put(skb, sizeof(struct iphdr) + 4);
 359
 360         pip->version  = 4;
 361         pip->ihl      = (sizeof(struct iphdr)+4)>>2;
 362         pip->tos      = 0xc0;
 363         pip->frag_off = htons(IP_DF);
 364         pip->ttl      = 1;
 365         pip->daddr    = fl4.daddr;
 366         pip->saddr    = fl4.saddr;
 367         pip->protocol = IPPROTO_IGMP;
 368         pip->tot_len  = 0;      /* filled in later */
 369         ip_select_ident(net, skb, NULL);
 370         ((u8 *)&pip[1])[0] = IPOPT_RA;
 371         ((u8 *)&pip[1])[1] = 4;
 372         ((u8 *)&pip[1])[2] = 0;
 373         ((u8 *)&pip[1])[3] = 0;
 374
 375         skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
 376         skb_put(skb, sizeof(*pig));
 377         pig = igmpv3_report_hdr(skb);
 378         pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
 379         pig->resv1 = 0;
 380         pig->csum = 0;
 381         pig->resv2 = 0;
 382         pig->ngrec = 0;
 383         return skb;
 384 }
 385
 386 static int igmpv3_sendpack(struct sk_buff *skb)
 387 {
 388         struct igmphdr *pig = igmp_hdr(skb);
 389         const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
 390
 391         pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
 392
 393         return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
 394 }
 395
 396 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
 397 {
 398         return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
 399 }
 400
 401 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
 402         int type, struct igmpv3_grec **ppgr)
 403 {
 404         struct net_device *dev = pmc->interface->dev;
 405         struct igmpv3_report *pih;
 406         struct igmpv3_grec *pgr;
 407
 408         if (!skb)
 409                 skb = igmpv3_newpack(dev, dev->mtu);
 410         if (!skb)
 411                 return NULL;
 412         pgr = (struct igmpv3_grec *)skb_put(skb, sizeof(struct igmpv3_grec));
 413         pgr->grec_type = type;
 414         pgr->grec_auxwords = 0;
 415         pgr->grec_nsrcs = 0;
 416         pgr->grec_mca = pmc->multiaddr;
 417         pih = igmpv3_report_hdr(skb);
 418         pih->ngrec = htons(ntohs(pih->ngrec)+1);
 419         *ppgr = pgr;
 420         return skb;
 421 }
 422
 423 #define AVAILABLE(skb)  ((skb) ? skb_availroom(skb) : 0)
 424
 425 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
 426         int type, int gdeleted, int sdeleted)
 427 {
 428         struct net_device *dev = pmc->interface->dev;
 429         struct net *net = dev_net(dev);
 430         struct igmpv3_report *pih;
 431         struct igmpv3_grec *pgr = NULL;
 432         struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
 433         int scount, stotal, first, isquery, truncate;
 434
 435         if (pmc->multiaddr == IGMP_ALL_HOSTS)
 436                 return skb;
 437         if (ipv4_is_local_multicast(pmc->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
 438                 return skb;
 439
 440         isquery = type == IGMPV3_MODE_IS_INCLUDE ||
 441                   type == IGMPV3_MODE_IS_EXCLUDE;
 442         truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
 443                     type == IGMPV3_CHANGE_TO_EXCLUDE;
 444
 445         stotal = scount = 0;
 446
 447         psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
 448
 449         if (!*psf_list)
 450                 goto empty_source;
 451
 452         pih = skb ? igmpv3_report_hdr(skb) : NULL;
 453
 454         /* EX and TO_EX get a fresh packet, if needed */
 455         if (truncate) {
 456                 if (pih && pih->ngrec &&
 457                     AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
 458                         if (skb)
 459                                 igmpv3_sendpack(skb);
 460                         skb = igmpv3_newpack(dev, dev->mtu);
 461                 }
 462         }
 463         first = 1;
 464         psf_prev = NULL;
 465         for (psf = *psf_list; psf; psf = psf_next) {
 466                 __be32 *psrc;
 467
 468                 psf_next = psf->sf_next;
 469
 470                 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
 471                         psf_prev = psf;
 472                         continue;
 473                 }
 474
 475                 /* Based on RFC3376 5.1. Should not send source-list change
 476                  * records when there is a filter mode change.
 477                  */
 478                 if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) ||
 479                      (!gdeleted && pmc->crcount)) &&
 480                     (type == IGMPV3_ALLOW_NEW_SOURCES ||
 481                      type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount)
 482                         goto decrease_sf_crcount;
 483
 484                 /* clear marks on query responses */
 485                 if (isquery)
 486                         psf->sf_gsresp = 0;
 487
 488                 if (AVAILABLE(skb) < sizeof(__be32) +
 489                     first*sizeof(struct igmpv3_grec)) {
 490                         if (truncate && !first)
 491                                 break;   /* truncate these */
 492                         if (pgr)
 493                                 pgr->grec_nsrcs = htons(scount);
 494                         if (skb)
 495                                 igmpv3_sendpack(skb);
 496                         skb = igmpv3_newpack(dev, dev->mtu);
 497                         first = 1;
 498                         scount = 0;
 499                 }
 500                 if (first) {
 501                         skb = add_grhead(skb, pmc, type, &pgr);
 502                         first = 0;
 503                 }
 504                 if (!skb)
 505                         return NULL;
 506                 psrc = (__be32 *)skb_put(skb, sizeof(__be32));
 507                 *psrc = psf->sf_inaddr;
 508                 scount++; stotal++;
 509                 if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
 510                      type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
 511 decrease_sf_crcount:
 512                         psf->sf_crcount--;
 513                         if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
 514                                 if (psf_prev)
 515                                         psf_prev->sf_next = psf->sf_next;
 516                                 else
 517                                         *psf_list = psf->sf_next;
 518                                 kfree(psf);
 519                                 continue;
 520                         }
 521                 }
 522                 psf_prev = psf;
 523         }
 524
 525 empty_source:
 526         if (!stotal) {
 527                 if (type == IGMPV3_ALLOW_NEW_SOURCES ||
 528                     type == IGMPV3_BLOCK_OLD_SOURCES)
 529                         return skb;
 530                 if (pmc->crcount || isquery) {
 531                         /* make sure we have room for group header */
 532                         if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) {
 533                                 igmpv3_sendpack(skb);
 534                                 skb = NULL; /* add_grhead will get a new one */
 535                         }
 536                         skb = add_grhead(skb, pmc, type, &pgr);
 537                 }
 538         }
 539         if (pgr)
 540                 pgr->grec_nsrcs = htons(scount);
 541
 542         if (isquery)
 543                 pmc->gsquery = 0;       /* clear query state on report */
 544         return skb;
 545 }
 546
 547 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
 548 {
 549         struct sk_buff *skb = NULL;
 550         struct net *net = dev_net(in_dev->dev);
 551         int type;
 552
 553         if (!pmc) {
 554                 rcu_read_lock();
 555                 for_each_pmc_rcu(in_dev, pmc) {
 556                         if (pmc->multiaddr == IGMP_ALL_HOSTS)
 557                                 continue;
 558                         if (ipv4_is_local_multicast(pmc->multiaddr) &&
 559                              !net->ipv4.sysctl_igmp_llm_reports)
 560                                 continue;
 561                         spin_lock_bh(&pmc->lock);
 562                         if (pmc->sfcount[MCAST_EXCLUDE])
 563                                 type = IGMPV3_MODE_IS_EXCLUDE;
 564                         else
 565                                 type = IGMPV3_MODE_IS_INCLUDE;
 566                         skb = add_grec(skb, pmc, type, 0, 0);
 567                         spin_unlock_bh(&pmc->lock);
 568                 }
 569                 rcu_read_unlock();
 570         } else {
 571                 spin_lock_bh(&pmc->lock);
 572                 if (pmc->sfcount[MCAST_EXCLUDE])
 573                         type = IGMPV3_MODE_IS_EXCLUDE;
 574                 else
 575                         type = IGMPV3_MODE_IS_INCLUDE;
 576                 skb = add_grec(skb, pmc, type, 0, 0);
 577                 spin_unlock_bh(&pmc->lock);
 578         }
 579         if (!skb)
 580                 return 0;
 581         return igmpv3_sendpack(skb);
 582 }
 583
 584 /*
 585  * remove zero-count source records from a source filter list
 586  */
 587 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
 588 {
 589         struct ip_sf_list *psf_prev, *psf_next, *psf;
 590
 591         psf_prev = NULL;
 592         for (psf = *ppsf; psf; psf = psf_next) {
 593                 psf_next = psf->sf_next;
 594                 if (psf->sf_crcount == 0) {
 595                         if (psf_prev)
 596                                 psf_prev->sf_next = psf->sf_next;
 597                         else
 598                                 *ppsf = psf->sf_next;
 599                         kfree(psf);
 600                 } else
 601                         psf_prev = psf;
 602         }
 603 }
 604
 605 static void igmpv3_send_cr(struct in_device *in_dev)
 606 {
 607         struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
 608         struct sk_buff *skb = NULL;
 609         int type, dtype;
 610
 611         rcu_read_lock();
 612         spin_lock_bh(&in_dev->mc_tomb_lock);
 613
 614         /* deleted MCA's */
 615         pmc_prev = NULL;
 616         for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) {
 617                 pmc_next = pmc->next;
 618                 if (pmc->sfmode == MCAST_INCLUDE) {
 619                         type = IGMPV3_BLOCK_OLD_SOURCES;
 620                         dtype = IGMPV3_BLOCK_OLD_SOURCES;
 621                         skb = add_grec(skb, pmc, type, 1, 0);
 622                         skb = add_grec(skb, pmc, dtype, 1, 1);
 623                 }
 624                 if (pmc->crcount) {
 625                         if (pmc->sfmode == MCAST_EXCLUDE) {
 626                                 type = IGMPV3_CHANGE_TO_INCLUDE;
 627                                 skb = add_grec(skb, pmc, type, 1, 0);
 628                         }
 629                         pmc->crcount--;
 630                         if (pmc->crcount == 0) {
 631                                 igmpv3_clear_zeros(&pmc->tomb);
 632                                 igmpv3_clear_zeros(&pmc->sources);
 633                         }
 634                 }
 635                 if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
 636                         if (pmc_prev)
 637                                 pmc_prev->next = pmc_next;
 638                         else
 639                                 in_dev->mc_tomb = pmc_next;
 640                         in_dev_put(pmc->interface);
 641                         kfree(pmc);
 642                 } else
 643                         pmc_prev = pmc;
 644         }
 645         spin_unlock_bh(&in_dev->mc_tomb_lock);
 646
 647         /* change recs */
 648         for_each_pmc_rcu(in_dev, pmc) {
 649                 spin_lock_bh(&pmc->lock);
 650                 if (pmc->sfcount[MCAST_EXCLUDE]) {
 651                         type = IGMPV3_BLOCK_OLD_SOURCES;
 652                         dtype = IGMPV3_ALLOW_NEW_SOURCES;
 653                 } else {
 654                         type = IGMPV3_ALLOW_NEW_SOURCES;
 655                         dtype = IGMPV3_BLOCK_OLD_SOURCES;
 656                 }
 657                 skb = add_grec(skb, pmc, type, 0, 0);
 658                 skb = add_grec(skb, pmc, dtype, 0, 1);  /* deleted sources */
 659
 660                 /* filter mode changes */
 661                 if (pmc->crcount) {
 662                         if (pmc->sfmode == MCAST_EXCLUDE)
 663                                 type = IGMPV3_CHANGE_TO_EXCLUDE;
 664                         else
 665                                 type = IGMPV3_CHANGE_TO_INCLUDE;
 666                         skb = add_grec(skb, pmc, type, 0, 0);
 667                         pmc->crcount--;
 668                 }
 669                 spin_unlock_bh(&pmc->lock);
 670         }
 671         rcu_read_unlock();
 672
 673         if (!skb)
 674                 return;
 675         (void) igmpv3_sendpack(skb);
 676 }
 677
 678 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
 679         int type)
 680 {
 681         struct sk_buff *skb;
 682         struct iphdr *iph;
 683         struct igmphdr *ih;
 684         struct rtable *rt;
 685         struct net_device *dev = in_dev->dev;
 686         struct net *net = dev_net(dev);
 687         __be32  group = pmc ? pmc->multiaddr : 0;
 688         struct flowi4 fl4;
 689         __be32  dst;
 690         int hlen, tlen;
 691
 692         if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
 693                 return igmpv3_send_report(in_dev, pmc);
 694
 695         if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
 696                 return 0;
 697
 698         if (type == IGMP_HOST_LEAVE_MESSAGE)
 699                 dst = IGMP_ALL_ROUTER;
 700         else
 701                 dst = group;
 702
 703         rt = ip_route_output_ports(net, &fl4, NULL, dst, 0,
 704                                    0, 0,
 705                                    IPPROTO_IGMP, 0, dev->ifindex);
 706         if (IS_ERR(rt))
 707                 return -1;
 708
 709         hlen = LL_RESERVED_SPACE(dev);
 710         tlen = dev->needed_tailroom;
 711         skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC);
 712         if (!skb) {
 713                 ip_rt_put(rt);
 714                 return -1;
 715         }
 716         skb->priority = TC_PRIO_CONTROL;
 717
 718         skb_dst_set(skb, &rt->dst);
 719
 720         skb_reserve(skb, hlen);
 721
 722         skb_reset_network_header(skb);
 723         iph = ip_hdr(skb);
 724         skb_put(skb, sizeof(struct iphdr) + 4);
 725
 726         iph->version  = 4;
 727         iph->ihl      = (sizeof(struct iphdr)+4)>>2;
 728         iph->tos      = 0xc0;
 729         iph->frag_off = htons(IP_DF);
 730         iph->ttl      = 1;
 731         iph->daddr    = dst;
 732         iph->saddr    = fl4.saddr;
 733         iph->protocol = IPPROTO_IGMP;
 734         ip_select_ident(net, skb, NULL);
 735         ((u8 *)&iph[1])[0] = IPOPT_RA;
 736         ((u8 *)&iph[1])[1] = 4;
 737         ((u8 *)&iph[1])[2] = 0;
 738         ((u8 *)&iph[1])[3] = 0;
 739
 740         ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
 741         ih->type = type;
 742         ih->code = 0;
 743         ih->csum = 0;
 744         ih->group = group;
 745         ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 746
 747         return ip_local_out(net, skb->sk, skb);
 748 }
 749
 750 static void igmp_gq_timer_expire(unsigned long data)
 751 {
 752         struct in_device *in_dev = (struct in_device *)data;
 753
 754         in_dev->mr_gq_running = 0;
 755         igmpv3_send_report(in_dev, NULL);
 756         in_dev_put(in_dev);
 757 }
 758
 759 static void igmp_ifc_timer_expire(unsigned long data)
 760 {
 761         struct in_device *in_dev = (struct in_device *)data;
 762
 763         igmpv3_send_cr(in_dev);
 764         if (in_dev->mr_ifc_count) {
 765                 in_dev->mr_ifc_count--;
 766                 igmp_ifc_start_timer(in_dev,
 767                                      unsolicited_report_interval(in_dev));
 768         }
 769         in_dev_put(in_dev);
 770 }
 771
 772 static void igmp_ifc_event(struct in_device *in_dev)
 773 {
 774         struct net *net = dev_net(in_dev->dev);
 775         if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 776                 return;
 777         in_dev->mr_ifc_count = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
 778         igmp_ifc_start_timer(in_dev, 1);
 779 }
 780
 781
 782 static void igmp_timer_expire(unsigned long data)
 783 {
 784         struct ip_mc_list *im = (struct ip_mc_list *)data;
 785         struct in_device *in_dev = im->interface;
 786
 787         spin_lock(&im->lock);
 788         im->tm_running = 0;
 789
 790         if (im->unsolicit_count) {
 791                 im->unsolicit_count--;
 792                 igmp_start_timer(im, unsolicited_report_interval(in_dev));
 793         }
 794         im->reporter = 1;
 795         spin_unlock(&im->lock);
 796
 797         if (IGMP_V1_SEEN(in_dev))
 798                 igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
 799         else if (IGMP_V2_SEEN(in_dev))
 800                 igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
 801         else
 802                 igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
 803
 804         ip_ma_put(im);
 805 }
 806
 807 /* mark EXCLUDE-mode sources */
 808 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 809 {
 810         struct ip_sf_list *psf;
 811         int i, scount;
 812
 813         scount = 0;
 814         for (psf = pmc->sources; psf; psf = psf->sf_next) {
 815                 if (scount == nsrcs)
 816                         break;
 817                 for (i = 0; i < nsrcs; i++) {
 818                         /* skip inactive filters */
 819                         if (psf->sf_count[MCAST_INCLUDE] ||
 820                             pmc->sfcount[MCAST_EXCLUDE] !=
 821                             psf->sf_count[MCAST_EXCLUDE])
 822                                 break;
 823                         if (srcs[i] == psf->sf_inaddr) {
 824                                 scount++;
 825                                 break;
 826                         }
 827                 }
 828         }
 829         pmc->gsquery = 0;
 830         if (scount == nsrcs)    /* all sources excluded */
 831                 return 0;
 832         return 1;
 833 }
 834
 835 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 836 {
 837         struct ip_sf_list *psf;
 838         int i, scount;
 839
 840         if (pmc->sfmode == MCAST_EXCLUDE)
 841                 return igmp_xmarksources(pmc, nsrcs, srcs);
 842
 843         /* mark INCLUDE-mode sources */
 844         scount = 0;
 845         for (psf = pmc->sources; psf; psf = psf->sf_next) {
 846                 if (scount == nsrcs)
 847                         break;
 848                 for (i = 0; i < nsrcs; i++)
 849                         if (srcs[i] == psf->sf_inaddr) {
 850                                 psf->sf_gsresp = 1;
 851                                 scount++;
 852                                 break;
 853                         }
 854         }
 855         if (!scount) {
 856                 pmc->gsquery = 0;
 857                 return 0;
 858         }
 859         pmc->gsquery = 1;
 860         return 1;
 861 }
 862
 863 /* return true if packet was dropped */
 864 static bool igmp_heard_report(struct in_device *in_dev, __be32 group)
 865 {
 866         struct ip_mc_list *im;
 867         struct net *net = dev_net(in_dev->dev);
 868
 869         /* Timers are only set for non-local groups */
 870
 871         if (group == IGMP_ALL_HOSTS)
 872                 return false;
 873         if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
 874                 return false;
 875
 876         rcu_read_lock();
 877         for_each_pmc_rcu(in_dev, im) {
 878                 if (im->multiaddr == group) {
 879                         igmp_stop_timer(im);
 880                         break;
 881                 }
 882         }
 883         rcu_read_unlock();
 884         return false;
 885 }
 886
 887 /* return true if packet was dropped */
 888 static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
 889         int len)
 890 {
 891         struct igmphdr          *ih = igmp_hdr(skb);
 892         struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
 893         struct ip_mc_list       *im;
 894         __be32                  group = ih->group;
 895         int                     max_delay;
 896         int                     mark = 0;
 897         struct net              *net = dev_net(in_dev->dev);
 898
 899
 900         if (len == 8) {
 901                 if (ih->code == 0) {
 902                         /* Alas, old v1 router presents here. */
 903
 904                         max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 905                         in_dev->mr_v1_seen = jiffies +
 906                                 IGMP_V1_ROUTER_PRESENT_TIMEOUT;
 907                         group = 0;
 908                 } else {
 909                         /* v2 router present */
 910                         max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
 911                         in_dev->mr_v2_seen = jiffies +
 912                                 IGMP_V2_ROUTER_PRESENT_TIMEOUT;
 913                 }
 914                 /* cancel the interface change timer */
 915                 in_dev->mr_ifc_count = 0;
 916                 if (del_timer(&in_dev->mr_ifc_timer))
 917                         __in_dev_put(in_dev);
 918                 /* clear deleted report items */
 919                 igmpv3_clear_delrec(in_dev);
 920         } else if (len < 12) {
 921                 return true;    /* ignore bogus packet; freed by caller */
 922         } else if (IGMP_V1_SEEN(in_dev)) {
 923                 /* This is a v3 query with v1 queriers present */
 924                 max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 925                 group = 0;
 926         } else if (IGMP_V2_SEEN(in_dev)) {
 927                 /* this is a v3 query with v2 queriers present;
 928                  * Interpretation of the max_delay code is problematic here.
 929                  * A real v2 host would use ih_code directly, while v3 has a
 930                  * different encoding. We use the v3 encoding as more likely
 931                  * to be intended in a v3 query.
 932                  */
 933                 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 934                 if (!max_delay)
 935                         max_delay = 1;  /* can't mod w/ 0 */
 936         } else { /* v3 */
 937                 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
 938                         return true;
 939
 940                 ih3 = igmpv3_query_hdr(skb);
 941                 if (ih3->nsrcs) {
 942                         if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
 943                                            + ntohs(ih3->nsrcs)*sizeof(__be32)))
 944                                 return true;
 945                         ih3 = igmpv3_query_hdr(skb);
 946                 }
 947
 948                 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 949                 if (!max_delay)
 950                         max_delay = 1;  /* can't mod w/ 0 */
 951                 in_dev->mr_maxdelay = max_delay;
 952                 if (ih3->qrv)
 953                         in_dev->mr_qrv = ih3->qrv;
 954                 if (!group) { /* general query */
 955                         if (ih3->nsrcs)
 956                                 return true;    /* no sources allowed */
 957                         igmp_gq_start_timer(in_dev);
 958                         return false;
 959                 }
 960                 /* mark sources to include, if group & source-specific */
 961                 mark = ih3->nsrcs != 0;
 962         }
 963
 964         /*
 965          * - Start the timers in all of our membership records
 966          *   that the query applies to for the interface on
 967          *   which the query arrived excl. those that belong
 968          *   to a "local" group (224.0.0.X)
 969          * - For timers already running check if they need to
 970          *   be reset.
 971          * - Use the igmp->igmp_code field as the maximum
 972          *   delay possible
 973          */
 974         rcu_read_lock();
 975         for_each_pmc_rcu(in_dev, im) {
 976                 int changed;
 977
 978                 if (group && group != im->multiaddr)
 979                         continue;
 980                 if (im->multiaddr == IGMP_ALL_HOSTS)
 981                         continue;
 982                 if (ipv4_is_local_multicast(im->multiaddr) &&
 983                     !net->ipv4.sysctl_igmp_llm_reports)
 984                         continue;
 985                 spin_lock_bh(&im->lock);
 986                 if (im->tm_running)
 987                         im->gsquery = im->gsquery && mark;
 988                 else
 989                         im->gsquery = mark;
 990                 changed = !im->gsquery ||
 991                         igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
 992                 spin_unlock_bh(&im->lock);
 993                 if (changed)
 994                         igmp_mod_timer(im, max_delay);
 995         }
 996         rcu_read_unlock();
 997         return false;
 998 }
 999
1000 /* called in rcu_read_lock() section */
1001 int igmp_rcv(struct sk_buff *skb)
1002 {
1003         /* This basically follows the spec line by line -- see RFC1112 */
1004         struct igmphdr *ih;
1005         struct in_device *in_dev = __in_dev_get_rcu(skb->dev);
1006         int len = skb->len;
1007         bool dropped = true;
1008
1009         if (!in_dev)
1010                 goto drop;
1011
1012         if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
1013                 goto drop;
1014
1015         if (skb_checksum_simple_validate(skb))
1016                 goto drop;
1017
1018         ih = igmp_hdr(skb);
1019         switch (ih->type) {
1020         case IGMP_HOST_MEMBERSHIP_QUERY:
1021                 dropped = igmp_heard_query(in_dev, skb, len);
1022                 break;
1023         case IGMP_HOST_MEMBERSHIP_REPORT:
1024         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1025                 /* Is it our report looped back? */
1026                 if (rt_is_output_route(skb_rtable(skb)))
1027                         break;
1028                 /* don't rely on MC router hearing unicast reports */
1029                 if (skb->pkt_type == PACKET_MULTICAST ||
1030                     skb->pkt_type == PACKET_BROADCAST)
1031                         dropped = igmp_heard_report(in_dev, ih->group);
1032                 break;
1033         case IGMP_PIM:
1034 #ifdef CONFIG_IP_PIMSM_V1
1035                 return pim_rcv_v1(skb);
1036 #endif
1037         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1038         case IGMP_DVMRP:
1039         case IGMP_TRACE:
1040         case IGMP_HOST_LEAVE_MESSAGE:
1041         case IGMP_MTRACE:
1042         case IGMP_MTRACE_RESP:
1043                 break;
1044         default:
1045                 break;
1046         }
1047
1048 drop:
1049         if (dropped)
1050                 kfree_skb(skb);
1051         else
1052                 consume_skb(skb);
1053         return 0;
1054 }
1055
1056 #endif
1057
1058
1059 /*
1060  *      Add a filter to a device
1061  */
1062
1063 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1064 {
1065         char buf[MAX_ADDR_LEN];
1066         struct net_device *dev = in_dev->dev;
1067
1068         /* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1069            We will get multicast token leakage, when IFF_MULTICAST
1070            is changed. This check should be done in ndo_set_rx_mode
1071            routine. Something sort of:
1072            if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1073            --ANK
1074            */
1075         if (arp_mc_map(addr, buf, dev, 0) == 0)
1076                 dev_mc_add(dev, buf);
1077 }
1078
1079 /*
1080  *      Remove a filter from a device
1081  */
1082
1083 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1084 {
1085         char buf[MAX_ADDR_LEN];
1086         struct net_device *dev = in_dev->dev;
1087
1088         if (arp_mc_map(addr, buf, dev, 0) == 0)
1089                 dev_mc_del(dev, buf);
1090 }
1091
1092 #ifdef CONFIG_IP_MULTICAST
1093 /*
1094  * deleted ip_mc_list manipulation
1095  */
1096 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1097 {
1098         struct ip_mc_list *pmc;
1099         struct net *net = dev_net(in_dev->dev);
1100
1101         /* this is an "ip_mc_list" for convenience; only the fields below
1102          * are actually used. In particular, the refcnt and users are not
1103          * used for management of the delete list. Using the same structure
1104          * for deleted items allows change reports to use common code with
1105          * non-deleted or query-response MCA's.
1106          */
1107         pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
1108         if (!pmc)
1109                 return;
1110         spin_lock_bh(&im->lock);
1111         pmc->interface = im->interface;
1112         in_dev_hold(in_dev);
1113         pmc->multiaddr = im->multiaddr;
1114         pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1115         pmc->sfmode = im->sfmode;
1116         if (pmc->sfmode == MCAST_INCLUDE) {
1117                 struct ip_sf_list *psf;
1118
1119                 pmc->tomb = im->tomb;
1120                 pmc->sources = im->sources;
1121                 im->tomb = im->sources = NULL;
1122                 for (psf = pmc->sources; psf; psf = psf->sf_next)
1123                         psf->sf_crcount = pmc->crcount;
1124         }
1125         spin_unlock_bh(&im->lock);
1126
1127         spin_lock_bh(&in_dev->mc_tomb_lock);
1128         pmc->next = in_dev->mc_tomb;
1129         in_dev->mc_tomb = pmc;
1130         spin_unlock_bh(&in_dev->mc_tomb_lock);
1131 }
1132
1133 static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr)
1134 {
1135         struct ip_mc_list *pmc, *pmc_prev;
1136         struct ip_sf_list *psf, *psf_next;
1137
1138         spin_lock_bh(&in_dev->mc_tomb_lock);
1139         pmc_prev = NULL;
1140         for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) {
1141                 if (pmc->multiaddr == multiaddr)
1142                         break;
1143                 pmc_prev = pmc;
1144         }
1145         if (pmc) {
1146                 if (pmc_prev)
1147                         pmc_prev->next = pmc->next;
1148                 else
1149                         in_dev->mc_tomb = pmc->next;
1150         }
1151         spin_unlock_bh(&in_dev->mc_tomb_lock);
1152         if (pmc) {
1153                 for (psf = pmc->tomb; psf; psf = psf_next) {
1154                         psf_next = psf->sf_next;
1155                         kfree(psf);
1156                 }
1157                 in_dev_put(pmc->interface);
1158                 kfree(pmc);
1159         }
1160 }
1161
1162 static void igmpv3_clear_delrec(struct in_device *in_dev)
1163 {
1164         struct ip_mc_list *pmc, *nextpmc;
1165
1166         spin_lock_bh(&in_dev->mc_tomb_lock);
1167         pmc = in_dev->mc_tomb;
1168         in_dev->mc_tomb = NULL;
1169         spin_unlock_bh(&in_dev->mc_tomb_lock);
1170
1171         for (; pmc; pmc = nextpmc) {
1172                 nextpmc = pmc->next;
1173                 ip_mc_clear_src(pmc);
1174                 in_dev_put(pmc->interface);
1175                 kfree(pmc);
1176         }
1177         /* clear dead sources, too */
1178         rcu_read_lock();
1179         for_each_pmc_rcu(in_dev, pmc) {
1180                 struct ip_sf_list *psf, *psf_next;
1181
1182                 spin_lock_bh(&pmc->lock);
1183                 psf = pmc->tomb;
1184                 pmc->tomb = NULL;
1185                 spin_unlock_bh(&pmc->lock);
1186                 for (; psf; psf = psf_next) {
1187                         psf_next = psf->sf_next;
1188                         kfree(psf);
1189                 }
1190         }
1191         rcu_read_unlock();
1192 }
1193 #endif
1194
1195 static void igmp_group_dropped(struct ip_mc_list *im)
1196 {
1197         struct in_device *in_dev = im->interface;
1198 #ifdef CONFIG_IP_MULTICAST
1199         struct net *net = dev_net(in_dev->dev);
1200         int reporter;
1201 #endif
1202
1203         if (im->loaded) {
1204                 im->loaded = 0;
1205                 ip_mc_filter_del(in_dev, im->multiaddr);
1206         }
1207
1208 #ifdef CONFIG_IP_MULTICAST
1209         if (im->multiaddr == IGMP_ALL_HOSTS)
1210                 return;
1211         if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1212                 return;
1213
1214         reporter = im->reporter;
1215         igmp_stop_timer(im);
1216
1217         if (!in_dev->dead) {
1218                 if (IGMP_V1_SEEN(in_dev))
1219                         return;
1220                 if (IGMP_V2_SEEN(in_dev)) {
1221                         if (reporter)
1222                                 igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1223                         return;
1224                 }
1225                 /* IGMPv3 */
1226                 igmpv3_add_delrec(in_dev, im);
1227
1228                 igmp_ifc_event(in_dev);
1229         }
1230 #endif
1231 }
1232
1233 static void igmp_group_added(struct ip_mc_list *im)
1234 {
1235         struct in_device *in_dev = im->interface;
1236 #ifdef CONFIG_IP_MULTICAST
1237         struct net *net = dev_net(in_dev->dev);
1238 #endif
1239
1240         if (im->loaded == 0) {
1241                 im->loaded = 1;
1242                 ip_mc_filter_add(in_dev, im->multiaddr);
1243         }
1244
1245 #ifdef CONFIG_IP_MULTICAST
1246         if (im->multiaddr == IGMP_ALL_HOSTS)
1247                 return;
1248         if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1249                 return;
1250
1251         if (in_dev->dead)
1252                 return;
1253         if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1254                 spin_lock_bh(&im->lock);
1255                 igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY);
1256                 spin_unlock_bh(&im->lock);
1257                 return;
1258         }
1259         /* else, v3 */
1260
1261         im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1262         igmp_ifc_event(in_dev);
1263 #endif
1264 }
1265
1266
1267 /*
1268  *      Multicast list managers
1269  */
1270
1271 static u32 ip_mc_hash(const struct ip_mc_list *im)
1272 {
1273         return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
1274 }
1275
1276 static void ip_mc_hash_add(struct in_device *in_dev,
1277                            struct ip_mc_list *im)
1278 {
1279         struct ip_mc_list __rcu **mc_hash;
1280         u32 hash;
1281
1282         mc_hash = rtnl_dereference(in_dev->mc_hash);
1283         if (mc_hash) {
1284                 hash = ip_mc_hash(im);
1285                 im->next_hash = mc_hash[hash];
1286                 rcu_assign_pointer(mc_hash[hash], im);
1287                 return;
1288         }
1289
1290         /* do not use a hash table for small number of items */
1291         if (in_dev->mc_count < 4)
1292                 return;
1293
1294         mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
1295                           GFP_KERNEL);
1296         if (!mc_hash)
1297                 return;
1298
1299         for_each_pmc_rtnl(in_dev, im) {
1300                 hash = ip_mc_hash(im);
1301                 im->next_hash = mc_hash[hash];
1302                 RCU_INIT_POINTER(mc_hash[hash], im);
1303         }
1304
1305         rcu_assign_pointer(in_dev->mc_hash, mc_hash);
1306 }
1307
1308 static void ip_mc_hash_remove(struct in_device *in_dev,
1309                               struct ip_mc_list *im)
1310 {
1311         struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
1312         struct ip_mc_list *aux;
1313
1314         if (!mc_hash)
1315                 return;
1316         mc_hash += ip_mc_hash(im);
1317         while ((aux = rtnl_dereference(*mc_hash)) != im)
1318                 mc_hash = &aux->next_hash;
1319         *mc_hash = im->next_hash;
1320 }
1321
1322
1323 /*
1324  *      A socket has joined a multicast group on device dev.
1325  */
1326
1327 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1328 {
1329         struct ip_mc_list *im;
1330 #ifdef CONFIG_IP_MULTICAST
1331         struct net *net = dev_net(in_dev->dev);
1332 #endif
1333
1334         ASSERT_RTNL();
1335
1336         for_each_pmc_rtnl(in_dev, im) {
1337                 if (im->multiaddr == addr) {
1338                         im->users++;
1339                         ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0);
1340                         goto out;
1341                 }
1342         }
1343
1344         im = kzalloc(sizeof(*im), GFP_KERNEL);
1345         if (!im)
1346                 goto out;
1347
1348         im->users = 1;
1349         im->interface = in_dev;
1350         in_dev_hold(in_dev);
1351         im->multiaddr = addr;
1352         /* initial mode is (EX, empty) */
1353         im->sfmode = MCAST_EXCLUDE;
1354         im->sfcount[MCAST_EXCLUDE] = 1;
1355         atomic_set(&im->refcnt, 1);
1356         spin_lock_init(&im->lock);
1357 #ifdef CONFIG_IP_MULTICAST
1358         setup_timer(&im->timer, igmp_timer_expire, (unsigned long)im);
1359         im->unsolicit_count = net->ipv4.sysctl_igmp_qrv;
1360 #endif
1361
1362         im->next_rcu = in_dev->mc_list;
1363         in_dev->mc_count++;
1364         rcu_assign_pointer(in_dev->mc_list, im);
1365
1366         ip_mc_hash_add(in_dev, im);
1367
1368 #ifdef CONFIG_IP_MULTICAST
1369         igmpv3_del_delrec(in_dev, im->multiaddr);
1370 #endif
1371         igmp_group_added(im);
1372         if (!in_dev->dead)
1373                 ip_rt_multicast_event(in_dev);
1374 out:
1375         return;
1376 }
1377 EXPORT_SYMBOL(ip_mc_inc_group);
1378
1379 static int ip_mc_check_iphdr(struct sk_buff *skb)
1380 {
1381         const struct iphdr *iph;
1382         unsigned int len;
1383         unsigned int offset = skb_network_offset(skb) + sizeof(*iph);
1384
1385         if (!pskb_may_pull(skb, offset))
1386                 return -EINVAL;
1387
1388         iph = ip_hdr(skb);
1389
1390         if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph))
1391                 return -EINVAL;
1392
1393         offset += ip_hdrlen(skb) - sizeof(*iph);
1394
1395         if (!pskb_may_pull(skb, offset))
1396                 return -EINVAL;
1397
1398         iph = ip_hdr(skb);
1399
1400         if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1401                 return -EINVAL;
1402
1403         len = skb_network_offset(skb) + ntohs(iph->tot_len);
1404         if (skb->len < len || len < offset)
1405                 return -EINVAL;
1406
1407         skb_set_transport_header(skb, offset);
1408
1409         return 0;
1410 }
1411
1412 static int ip_mc_check_igmp_reportv3(struct sk_buff *skb)
1413 {
1414         unsigned int len = skb_transport_offset(skb);
1415
1416         len += sizeof(struct igmpv3_report);
1417
1418         return pskb_may_pull(skb, len) ? 0 : -EINVAL;
1419 }
1420
1421 static int ip_mc_check_igmp_query(struct sk_buff *skb)
1422 {
1423         unsigned int len = skb_transport_offset(skb);
1424
1425         len += sizeof(struct igmphdr);
1426         if (skb->len < len)
1427                 return -EINVAL;
1428
1429         /* IGMPv{1,2}? */
1430         if (skb->len != len) {
1431                 /* or IGMPv3? */
1432                 len += sizeof(struct igmpv3_query) - sizeof(struct igmphdr);
1433                 if (skb->len < len || !pskb_may_pull(skb, len))
1434                         return -EINVAL;
1435         }
1436
1437         /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1438          * all-systems destination addresses (224.0.0.1) for general queries
1439          */
1440         if (!igmp_hdr(skb)->group &&
1441             ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP))
1442                 return -EINVAL;
1443
1444         return 0;
1445 }
1446
1447 static int ip_mc_check_igmp_msg(struct sk_buff *skb)
1448 {
1449         switch (igmp_hdr(skb)->type) {
1450         case IGMP_HOST_LEAVE_MESSAGE:
1451         case IGMP_HOST_MEMBERSHIP_REPORT:
1452         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1453                 /* fall through */
1454                 return 0;
1455         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1456                 return ip_mc_check_igmp_reportv3(skb);
1457         case IGMP_HOST_MEMBERSHIP_QUERY:
1458                 return ip_mc_check_igmp_query(skb);
1459         default:
1460                 return -ENOMSG;
1461         }
1462 }
1463
1464 static inline __sum16 ip_mc_validate_checksum(struct sk_buff *skb)
1465 {
1466         return skb_checksum_simple_validate(skb);
1467 }
1468
1469 static int __ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
1470
1471 {
1472         struct sk_buff *skb_chk;
1473         unsigned int transport_len;
1474         unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr);
1475         int ret = -EINVAL;
1476
1477         transport_len = ntohs(ip_hdr(skb)->tot_len) - ip_hdrlen(skb);
1478
1479         skb_chk = skb_checksum_trimmed(skb, transport_len,
1480                                        ip_mc_validate_checksum);
1481         if (!skb_chk)
1482                 goto err;
1483
1484         if (!pskb_may_pull(skb_chk, len))
1485                 goto err;
1486
1487         ret = ip_mc_check_igmp_msg(skb_chk);
1488         if (ret)
1489                 goto err;
1490
1491         if (skb_trimmed)
1492                 *skb_trimmed = skb_chk;
1493         /* free now unneeded clone */
1494         else if (skb_chk != skb)
1495                 kfree_skb(skb_chk);
1496
1497         ret = 0;
1498
1499 err:
1500         if (ret && skb_chk && skb_chk != skb)
1501                 kfree_skb(skb_chk);
1502
1503         return ret;
1504 }
1505
1506 /**
1507  * ip_mc_check_igmp - checks whether this is a sane IGMP packet
1508  * @skb: the skb to validate
1509  * @skb_trimmed: to store an skb pointer trimmed to IPv4 packet tail (optional)
1510  *
1511  * Checks whether an IPv4 packet is a valid IGMP packet. If so sets
1512  * skb transport header accordingly and returns zero.
1513  *
1514  * -EINVAL: A broken packet was detected, i.e. it violates some internet
1515  *  standard
1516  * -ENOMSG: IP header validation succeeded but it is not an IGMP packet.
1517  * -ENOMEM: A memory allocation failure happened.
1518  *
1519  * Optionally, an skb pointer might be provided via skb_trimmed (or set it
1520  * to NULL): After parsing an IGMP packet successfully it will point to
1521  * an skb which has its tail aligned to the IP packet end. This might
1522  * either be the originally provided skb or a trimmed, cloned version if
1523  * the skb frame had data beyond the IP packet. A cloned skb allows us
1524  * to leave the original skb and its full frame unchanged (which might be
1525  * desirable for layer 2 frame jugglers).
1526  *
1527  * Caller needs to set the skb network header and free any returned skb if it
1528  * differs from the provided skb.
1529  */
1530 int ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed)
1531 {
1532         int ret = ip_mc_check_iphdr(skb);
1533
1534         if (ret < 0)
1535                 return ret;
1536
1537         if (ip_hdr(skb)->protocol != IPPROTO_IGMP)
1538                 return -ENOMSG;
1539
1540         return __ip_mc_check_igmp(skb, skb_trimmed);
1541 }
1542 EXPORT_SYMBOL(ip_mc_check_igmp);
1543
1544 /*
1545  *      Resend IGMP JOIN report; used by netdev notifier.
1546  */
1547 static void ip_mc_rejoin_groups(struct in_device *in_dev)
1548 {
1549 #ifdef CONFIG_IP_MULTICAST
1550         struct ip_mc_list *im;
1551         int type;
1552         struct net *net = dev_net(in_dev->dev);
1553
1554         ASSERT_RTNL();
1555
1556         for_each_pmc_rtnl(in_dev, im) {
1557                 if (im->multiaddr == IGMP_ALL_HOSTS)
1558                         continue;
1559                 if (ipv4_is_local_multicast(im->multiaddr) &&
1560                     !net->ipv4.sysctl_igmp_llm_reports)
1561                         continue;
1562
1563                 /* a failover is happening and switches
1564                  * must be notified immediately
1565                  */
1566                 if (IGMP_V1_SEEN(in_dev))
1567                         type = IGMP_HOST_MEMBERSHIP_REPORT;
1568                 else if (IGMP_V2_SEEN(in_dev))
1569                         type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1570                 else
1571                         type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1572                 igmp_send_report(in_dev, im, type);
1573         }
1574 #endif
1575 }
1576
1577 /*
1578  *      A socket has left a multicast group on device dev
1579  */
1580
1581 void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
1582 {
1583         struct ip_mc_list *i;
1584         struct ip_mc_list __rcu **ip;
1585
1586         ASSERT_RTNL();
1587
1588         for (ip = &in_dev->mc_list;
1589              (i = rtnl_dereference(*ip)) != NULL;
1590              ip = &i->next_rcu) {
1591                 if (i->multiaddr == addr) {
1592                         if (--i->users == 0) {
1593                                 ip_mc_hash_remove(in_dev, i);
1594                                 *ip = i->next_rcu;
1595                                 in_dev->mc_count--;
1596                                 igmp_group_dropped(i);
1597                                 ip_mc_clear_src(i);
1598
1599                                 if (!in_dev->dead)
1600                                         ip_rt_multicast_event(in_dev);
1601
1602                                 ip_ma_put(i);
1603                                 return;
1604                         }
1605                         break;
1606                 }
1607         }
1608 }
1609 EXPORT_SYMBOL(ip_mc_dec_group);
1610
1611 /* Device changing type */
1612
1613 void ip_mc_unmap(struct in_device *in_dev)
1614 {
1615         struct ip_mc_list *pmc;
1616
1617         ASSERT_RTNL();
1618
1619         for_each_pmc_rtnl(in_dev, pmc)
1620                 igmp_group_dropped(pmc);
1621 }
1622
1623 void ip_mc_remap(struct in_device *in_dev)
1624 {
1625         struct ip_mc_list *pmc;
1626
1627         ASSERT_RTNL();
1628
1629         for_each_pmc_rtnl(in_dev, pmc)
1630                 igmp_group_added(pmc);
1631 }
1632
1633 /* Device going down */
1634
1635 void ip_mc_down(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 #ifdef CONFIG_IP_MULTICAST
1645         in_dev->mr_ifc_count = 0;
1646         if (del_timer(&in_dev->mr_ifc_timer))
1647                 __in_dev_put(in_dev);
1648         in_dev->mr_gq_running = 0;
1649         if (del_timer(&in_dev->mr_gq_timer))
1650                 __in_dev_put(in_dev);
1651         igmpv3_clear_delrec(in_dev);
1652 #endif
1653
1654         ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1655 }
1656
1657 void ip_mc_init_dev(struct in_device *in_dev)
1658 {
1659 #ifdef CONFIG_IP_MULTICAST
1660         struct net *net = dev_net(in_dev->dev);
1661 #endif
1662         ASSERT_RTNL();
1663
1664 #ifdef CONFIG_IP_MULTICAST
1665         setup_timer(&in_dev->mr_gq_timer, igmp_gq_timer_expire,
1666                         (unsigned long)in_dev);
1667         setup_timer(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire,
1668                         (unsigned long)in_dev);
1669         in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1670 #endif
1671
1672         spin_lock_init(&in_dev->mc_tomb_lock);
1673 }
1674
1675 /* Device going up */
1676
1677 void ip_mc_up(struct in_device *in_dev)
1678 {
1679         struct ip_mc_list *pmc;
1680 #ifdef CONFIG_IP_MULTICAST
1681         struct net *net = dev_net(in_dev->dev);
1682 #endif
1683
1684         ASSERT_RTNL();
1685
1686 #ifdef CONFIG_IP_MULTICAST
1687         in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1688 #endif
1689         ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1690
1691         for_each_pmc_rtnl(in_dev, pmc)
1692                 igmp_group_added(pmc);
1693 }
1694
1695 /*
1696  *      Device is about to be destroyed: clean up.
1697  */
1698
1699 void ip_mc_destroy_dev(struct in_device *in_dev)
1700 {
1701         struct ip_mc_list *i;
1702
1703         ASSERT_RTNL();
1704
1705         /* Deactivate timers */
1706         ip_mc_down(in_dev);
1707
1708         while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1709                 in_dev->mc_list = i->next_rcu;
1710                 in_dev->mc_count--;
1711
1712                 /* We've dropped the groups in ip_mc_down already */
1713                 ip_mc_clear_src(i);
1714                 ip_ma_put(i);
1715         }
1716 }
1717
1718 /* RTNL is locked */
1719 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1720 {
1721         struct net_device *dev = NULL;
1722         struct in_device *idev = NULL;
1723
1724         if (imr->imr_ifindex) {
1725                 idev = inetdev_by_index(net, imr->imr_ifindex);
1726                 return idev;
1727         }
1728         if (imr->imr_address.s_addr) {
1729                 dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1730                 if (!dev)
1731                         return NULL;
1732         }
1733
1734         if (!dev) {
1735                 struct rtable *rt = ip_route_output(net,
1736                                                     imr->imr_multiaddr.s_addr,
1737                                                     0, 0, 0);
1738                 if (!IS_ERR(rt)) {
1739                         dev = rt->dst.dev;
1740                         ip_rt_put(rt);
1741                 }
1742         }
1743         if (dev) {
1744                 imr->imr_ifindex = dev->ifindex;
1745                 idev = __in_dev_get_rtnl(dev);
1746         }
1747         return idev;
1748 }
1749
1750 /*
1751  *      Join a socket to a group
1752  */
1753
1754 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1755         __be32 *psfsrc)
1756 {
1757         struct ip_sf_list *psf, *psf_prev;
1758         int rv = 0;
1759
1760         psf_prev = NULL;
1761         for (psf = pmc->sources; psf; psf = psf->sf_next) {
1762                 if (psf->sf_inaddr == *psfsrc)
1763                         break;
1764                 psf_prev = psf;
1765         }
1766         if (!psf || psf->sf_count[sfmode] == 0) {
1767                 /* source filter not found, or count wrong =>  bug */
1768                 return -ESRCH;
1769         }
1770         psf->sf_count[sfmode]--;
1771         if (psf->sf_count[sfmode] == 0) {
1772                 ip_rt_multicast_event(pmc->interface);
1773         }
1774         if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1775 #ifdef CONFIG_IP_MULTICAST
1776                 struct in_device *in_dev = pmc->interface;
1777                 struct net *net = dev_net(in_dev->dev);
1778 #endif
1779
1780                 /* no more filters for this source */
1781                 if (psf_prev)
1782                         psf_prev->sf_next = psf->sf_next;
1783                 else
1784                         pmc->sources = psf->sf_next;
1785 #ifdef CONFIG_IP_MULTICAST
1786                 if (psf->sf_oldin &&
1787                     !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1788                         psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1789                         psf->sf_next = pmc->tomb;
1790                         pmc->tomb = psf;
1791                         rv = 1;
1792                 } else
1793 #endif
1794                         kfree(psf);
1795         }
1796         return rv;
1797 }
1798
1799 #ifndef CONFIG_IP_MULTICAST
1800 #define igmp_ifc_event(x)       do { } while (0)
1801 #endif
1802
1803 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1804                          int sfcount, __be32 *psfsrc, int delta)
1805 {
1806         struct ip_mc_list *pmc;
1807         int     changerec = 0;
1808         int     i, err;
1809
1810         if (!in_dev)
1811                 return -ENODEV;
1812         rcu_read_lock();
1813         for_each_pmc_rcu(in_dev, pmc) {
1814                 if (*pmca == pmc->multiaddr)
1815                         break;
1816         }
1817         if (!pmc) {
1818                 /* MCA not found?? bug */
1819                 rcu_read_unlock();
1820                 return -ESRCH;
1821         }
1822         spin_lock_bh(&pmc->lock);
1823         rcu_read_unlock();
1824 #ifdef CONFIG_IP_MULTICAST
1825         sf_markstate(pmc);
1826 #endif
1827         if (!delta) {
1828                 err = -EINVAL;
1829                 if (!pmc->sfcount[sfmode])
1830                         goto out_unlock;
1831                 pmc->sfcount[sfmode]--;
1832         }
1833         err = 0;
1834         for (i = 0; i < sfcount; i++) {
1835                 int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1836
1837                 changerec |= rv > 0;
1838                 if (!err && rv < 0)
1839                         err = rv;
1840         }
1841         if (pmc->sfmode == MCAST_EXCLUDE &&
1842             pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1843             pmc->sfcount[MCAST_INCLUDE]) {
1844 #ifdef CONFIG_IP_MULTICAST
1845                 struct ip_sf_list *psf;
1846                 struct net *net = dev_net(in_dev->dev);
1847 #endif
1848
1849                 /* filter mode change */
1850                 pmc->sfmode = MCAST_INCLUDE;
1851 #ifdef CONFIG_IP_MULTICAST
1852                 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1853                 in_dev->mr_ifc_count = pmc->crcount;
1854                 for (psf = pmc->sources; psf; psf = psf->sf_next)
1855                         psf->sf_crcount = 0;
1856                 igmp_ifc_event(pmc->interface);
1857         } else if (sf_setstate(pmc) || changerec) {
1858                 igmp_ifc_event(pmc->interface);
1859 #endif
1860         }
1861 out_unlock:
1862         spin_unlock_bh(&pmc->lock);
1863         return err;
1864 }
1865
1866 /*
1867  * Add multicast single-source filter to the interface list
1868  */
1869 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1870         __be32 *psfsrc)
1871 {
1872         struct ip_sf_list *psf, *psf_prev;
1873
1874         psf_prev = NULL;
1875         for (psf = pmc->sources; psf; psf = psf->sf_next) {
1876                 if (psf->sf_inaddr == *psfsrc)
1877                         break;
1878                 psf_prev = psf;
1879         }
1880         if (!psf) {
1881                 psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1882                 if (!psf)
1883                         return -ENOBUFS;
1884                 psf->sf_inaddr = *psfsrc;
1885                 if (psf_prev) {
1886                         psf_prev->sf_next = psf;
1887                 } else
1888                         pmc->sources = psf;
1889         }
1890         psf->sf_count[sfmode]++;
1891         if (psf->sf_count[sfmode] == 1) {
1892                 ip_rt_multicast_event(pmc->interface);
1893         }
1894         return 0;
1895 }
1896
1897 #ifdef CONFIG_IP_MULTICAST
1898 static void sf_markstate(struct ip_mc_list *pmc)
1899 {
1900         struct ip_sf_list *psf;
1901         int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1902
1903         for (psf = pmc->sources; psf; psf = psf->sf_next)
1904                 if (pmc->sfcount[MCAST_EXCLUDE]) {
1905                         psf->sf_oldin = mca_xcount ==
1906                                 psf->sf_count[MCAST_EXCLUDE] &&
1907                                 !psf->sf_count[MCAST_INCLUDE];
1908                 } else
1909                         psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
1910 }
1911
1912 static int sf_setstate(struct ip_mc_list *pmc)
1913 {
1914         struct ip_sf_list *psf, *dpsf;
1915         int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1916         int qrv = pmc->interface->mr_qrv;
1917         int new_in, rv;
1918
1919         rv = 0;
1920         for (psf = pmc->sources; psf; psf = psf->sf_next) {
1921                 if (pmc->sfcount[MCAST_EXCLUDE]) {
1922                         new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
1923                                 !psf->sf_count[MCAST_INCLUDE];
1924                 } else
1925                         new_in = psf->sf_count[MCAST_INCLUDE] != 0;
1926                 if (new_in) {
1927                         if (!psf->sf_oldin) {
1928                                 struct ip_sf_list *prev = NULL;
1929
1930                                 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) {
1931                                         if (dpsf->sf_inaddr == psf->sf_inaddr)
1932                                                 break;
1933                                         prev = dpsf;
1934                                 }
1935                                 if (dpsf) {
1936                                         if (prev)
1937                                                 prev->sf_next = dpsf->sf_next;
1938                                         else
1939                                                 pmc->tomb = dpsf->sf_next;
1940                                         kfree(dpsf);
1941                                 }
1942                                 psf->sf_crcount = qrv;
1943                                 rv++;
1944                         }
1945                 } else if (psf->sf_oldin) {
1946
1947                         psf->sf_crcount = 0;
1948                         /*
1949                          * add or update "delete" records if an active filter
1950                          * is now inactive
1951                          */
1952                         for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next)
1953                                 if (dpsf->sf_inaddr == psf->sf_inaddr)
1954                                         break;
1955                         if (!dpsf) {
1956                                 dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
1957                                 if (!dpsf)
1958                                         continue;
1959                                 *dpsf = *psf;
1960                                 /* pmc->lock held by callers */
1961                                 dpsf->sf_next = pmc->tomb;
1962                                 pmc->tomb = dpsf;
1963                         }
1964                         dpsf->sf_crcount = qrv;
1965                         rv++;
1966                 }
1967         }
1968         return rv;
1969 }
1970 #endif
1971
1972 /*
1973  * Add multicast source filter list to the interface list
1974  */
1975 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1976                          int sfcount, __be32 *psfsrc, int delta)
1977 {
1978         struct ip_mc_list *pmc;
1979         int     isexclude;
1980         int     i, err;
1981
1982         if (!in_dev)
1983                 return -ENODEV;
1984         rcu_read_lock();
1985         for_each_pmc_rcu(in_dev, pmc) {
1986                 if (*pmca == pmc->multiaddr)
1987                         break;
1988         }
1989         if (!pmc) {
1990                 /* MCA not found?? bug */
1991                 rcu_read_unlock();
1992                 return -ESRCH;
1993         }
1994         spin_lock_bh(&pmc->lock);
1995         rcu_read_unlock();
1996
1997 #ifdef CONFIG_IP_MULTICAST
1998         sf_markstate(pmc);
1999 #endif
2000         isexclude = pmc->sfmode == MCAST_EXCLUDE;
2001         if (!delta)
2002                 pmc->sfcount[sfmode]++;
2003         err = 0;
2004         for (i = 0; i < sfcount; i++) {
2005                 err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2006                 if (err)
2007                         break;
2008         }
2009         if (err) {
2010                 int j;
2011
2012                 if (!delta)
2013                         pmc->sfcount[sfmode]--;
2014                 for (j = 0; j < i; j++)
2015                         (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2016         } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
2017 #ifdef CONFIG_IP_MULTICAST
2018                 struct ip_sf_list *psf;
2019                 struct net *net = dev_net(pmc->interface->dev);
2020                 in_dev = pmc->interface;
2021 #endif
2022
2023                 /* filter mode change */
2024                 if (pmc->sfcount[MCAST_EXCLUDE])
2025                         pmc->sfmode = MCAST_EXCLUDE;
2026                 else if (pmc->sfcount[MCAST_INCLUDE])
2027                         pmc->sfmode = MCAST_INCLUDE;
2028 #ifdef CONFIG_IP_MULTICAST
2029                 /* else no filters; keep old mode for reports */
2030
2031                 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
2032                 in_dev->mr_ifc_count = pmc->crcount;
2033                 for (psf = pmc->sources; psf; psf = psf->sf_next)
2034                         psf->sf_crcount = 0;
2035                 igmp_ifc_event(in_dev);
2036         } else if (sf_setstate(pmc)) {
2037                 igmp_ifc_event(in_dev);
2038 #endif
2039         }
2040         spin_unlock_bh(&pmc->lock);
2041         return err;
2042 }
2043
2044 static void ip_mc_clear_src(struct ip_mc_list *pmc)
2045 {
2046         struct ip_sf_list *psf, *nextpsf;
2047
2048         for (psf = pmc->tomb; psf; psf = nextpsf) {
2049                 nextpsf = psf->sf_next;
2050                 kfree(psf);
2051         }
2052         pmc->tomb = NULL;
2053         for (psf = pmc->sources; psf; psf = nextpsf) {
2054                 nextpsf = psf->sf_next;
2055                 kfree(psf);
2056         }
2057         pmc->sources = NULL;
2058         pmc->sfmode = MCAST_EXCLUDE;
2059         pmc->sfcount[MCAST_INCLUDE] = 0;
2060         pmc->sfcount[MCAST_EXCLUDE] = 1;
2061 }
2062
2063 /* Join a multicast group
2064  */
2065
2066 int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
2067 {
2068         __be32 addr = imr->imr_multiaddr.s_addr;
2069         struct ip_mc_socklist *iml, *i;
2070         struct in_device *in_dev;
2071         struct inet_sock *inet = inet_sk(sk);
2072         struct net *net = sock_net(sk);
2073         int ifindex;
2074         int count = 0;
2075         int err;
2076
2077         ASSERT_RTNL();
2078
2079         if (!ipv4_is_multicast(addr))
2080                 return -EINVAL;
2081
2082         in_dev = ip_mc_find_dev(net, imr);
2083
2084         if (!in_dev) {
2085                 err = -ENODEV;
2086                 goto done;
2087         }
2088
2089         err = -EADDRINUSE;
2090         ifindex = imr->imr_ifindex;
2091         for_each_pmc_rtnl(inet, i) {
2092                 if (i->multi.imr_multiaddr.s_addr == addr &&
2093                     i->multi.imr_ifindex == ifindex)
2094                         goto done;
2095                 count++;
2096         }
2097         err = -ENOBUFS;
2098         if (count >= net->ipv4.sysctl_igmp_max_memberships)
2099                 goto done;
2100         iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
2101         if (!iml)
2102                 goto done;
2103
2104         memcpy(&iml->multi, imr, sizeof(*imr));
2105         iml->next_rcu = inet->mc_list;
2106         iml->sflist = NULL;
2107         iml->sfmode = MCAST_EXCLUDE;
2108         rcu_assign_pointer(inet->mc_list, iml);
2109         ip_mc_inc_group(in_dev, addr);
2110         err = 0;
2111 done:
2112         return err;
2113 }
2114 EXPORT_SYMBOL(ip_mc_join_group);
2115
2116 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
2117                            struct in_device *in_dev)
2118 {
2119         struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
2120         int err;
2121
2122         if (!psf) {
2123                 /* any-source empty exclude case */
2124                 return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2125                         iml->sfmode, 0, NULL, 0);
2126         }
2127         err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2128                         iml->sfmode, psf->sl_count, psf->sl_addr, 0);
2129         RCU_INIT_POINTER(iml->sflist, NULL);
2130         /* decrease mem now to avoid the memleak warning */
2131         atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc);
2132         kfree_rcu(psf, rcu);
2133         return err;
2134 }
2135
2136 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
2137 {
2138         struct inet_sock *inet = inet_sk(sk);
2139         struct ip_mc_socklist *iml;
2140         struct ip_mc_socklist __rcu **imlp;
2141         struct in_device *in_dev;
2142         struct net *net = sock_net(sk);
2143         __be32 group = imr->imr_multiaddr.s_addr;
2144         u32 ifindex;
2145         int ret = -EADDRNOTAVAIL;
2146
2147         ASSERT_RTNL();
2148
2149         in_dev = ip_mc_find_dev(net, imr);
2150         if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) {
2151                 ret = -ENODEV;
2152                 goto out;
2153         }
2154         ifindex = imr->imr_ifindex;
2155         for (imlp = &inet->mc_list;
2156              (iml = rtnl_dereference(*imlp)) != NULL;
2157              imlp = &iml->next_rcu) {
2158                 if (iml->multi.imr_multiaddr.s_addr != group)
2159                         continue;
2160                 if (ifindex) {
2161                         if (iml->multi.imr_ifindex != ifindex)
2162                                 continue;
2163                 } else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
2164                                 iml->multi.imr_address.s_addr)
2165                         continue;
2166
2167                 (void) ip_mc_leave_src(sk, iml, in_dev);
2168
2169                 *imlp = iml->next_rcu;
2170
2171                 if (in_dev)
2172                         ip_mc_dec_group(in_dev, group);
2173
2174                 /* decrease mem now to avoid the memleak warning */
2175                 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2176                 kfree_rcu(iml, rcu);
2177                 return 0;
2178         }
2179 out:
2180         return ret;
2181 }
2182 EXPORT_SYMBOL(ip_mc_leave_group);
2183
2184 int ip_mc_source(int add, int omode, struct sock *sk, struct
2185         ip_mreq_source *mreqs, int ifindex)
2186 {
2187         int err;
2188         struct ip_mreqn imr;
2189         __be32 addr = mreqs->imr_multiaddr;
2190         struct ip_mc_socklist *pmc;
2191         struct in_device *in_dev = NULL;
2192         struct inet_sock *inet = inet_sk(sk);
2193         struct ip_sf_socklist *psl;
2194         struct net *net = sock_net(sk);
2195         int leavegroup = 0;
2196         int i, j, rv;
2197
2198         if (!ipv4_is_multicast(addr))
2199                 return -EINVAL;
2200
2201         ASSERT_RTNL();
2202
2203         imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
2204         imr.imr_address.s_addr = mreqs->imr_interface;
2205         imr.imr_ifindex = ifindex;
2206         in_dev = ip_mc_find_dev(net, &imr);
2207
2208         if (!in_dev) {
2209                 err = -ENODEV;
2210                 goto done;
2211         }
2212         err = -EADDRNOTAVAIL;
2213
2214         for_each_pmc_rtnl(inet, pmc) {
2215                 if ((pmc->multi.imr_multiaddr.s_addr ==
2216                      imr.imr_multiaddr.s_addr) &&
2217                     (pmc->multi.imr_ifindex == imr.imr_ifindex))
2218                         break;
2219         }
2220         if (!pmc) {             /* must have a prior join */
2221                 err = -EINVAL;
2222                 goto done;
2223         }
2224         /* if a source filter was set, must be the same mode as before */
2225         if (pmc->sflist) {
2226                 if (pmc->sfmode != omode) {
2227                         err = -EINVAL;
2228                         goto done;
2229                 }
2230         } else if (pmc->sfmode != omode) {
2231                 /* allow mode switches for empty-set filters */
2232                 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
2233                 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
2234                         NULL, 0);
2235                 pmc->sfmode = omode;
2236         }
2237
2238         psl = rtnl_dereference(pmc->sflist);
2239         if (!add) {
2240                 if (!psl)
2241                         goto done;      /* err = -EADDRNOTAVAIL */
2242                 rv = !0;
2243                 for (i = 0; i < psl->sl_count; i++) {
2244                         rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2245                                 sizeof(__be32));
2246                         if (rv == 0)
2247                                 break;
2248                 }
2249                 if (rv)         /* source not found */
2250                         goto done;      /* err = -EADDRNOTAVAIL */
2251
2252                 /* special case - (INCLUDE, empty) == LEAVE_GROUP */
2253                 if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
2254                         leavegroup = 1;
2255                         goto done;
2256                 }
2257
2258                 /* update the interface filter */
2259                 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2260                         &mreqs->imr_sourceaddr, 1);
2261
2262                 for (j = i+1; j < psl->sl_count; j++)
2263                         psl->sl_addr[j-1] = psl->sl_addr[j];
2264                 psl->sl_count--;
2265                 err = 0;
2266                 goto done;
2267         }
2268         /* else, add a new source to the filter */
2269
2270         if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) {
2271                 err = -ENOBUFS;
2272                 goto done;
2273         }
2274         if (!psl || psl->sl_count == psl->sl_max) {
2275                 struct ip_sf_socklist *newpsl;
2276                 int count = IP_SFBLOCK;
2277
2278                 if (psl)
2279                         count += psl->sl_max;
2280                 newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
2281                 if (!newpsl) {
2282                         err = -ENOBUFS;
2283                         goto done;
2284                 }
2285                 newpsl->sl_max = count;
2286                 newpsl->sl_count = count - IP_SFBLOCK;
2287                 if (psl) {
2288                         for (i = 0; i < psl->sl_count; i++)
2289                                 newpsl->sl_addr[i] = psl->sl_addr[i];
2290                         /* decrease mem now to avoid the memleak warning */
2291                         atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2292                         kfree_rcu(psl, rcu);
2293                 }
2294                 rcu_assign_pointer(pmc->sflist, newpsl);
2295                 psl = newpsl;
2296         }
2297         rv = 1; /* > 0 for insert logic below if sl_count is 0 */
2298         for (i = 0; i < psl->sl_count; i++) {
2299                 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2300                         sizeof(__be32));
2301                 if (rv == 0)
2302                         break;
2303         }
2304         if (rv == 0)            /* address already there is an error */
2305                 goto done;
2306         for (j = psl->sl_count-1; j >= i; j--)
2307                 psl->sl_addr[j+1] = psl->sl_addr[j];
2308         psl->sl_addr[i] = mreqs->imr_sourceaddr;
2309         psl->sl_count++;
2310         err = 0;
2311         /* update the interface list */
2312         ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2313                 &mreqs->imr_sourceaddr, 1);
2314 done:
2315         if (leavegroup)
2316                 err = ip_mc_leave_group(sk, &imr);
2317         return err;
2318 }
2319
2320 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2321 {
2322         int err = 0;
2323         struct ip_mreqn imr;
2324         __be32 addr = msf->imsf_multiaddr;
2325         struct ip_mc_socklist *pmc;
2326         struct in_device *in_dev;
2327         struct inet_sock *inet = inet_sk(sk);
2328         struct ip_sf_socklist *newpsl, *psl;
2329         struct net *net = sock_net(sk);
2330         int leavegroup = 0;
2331
2332         if (!ipv4_is_multicast(addr))
2333                 return -EINVAL;
2334         if (msf->imsf_fmode != MCAST_INCLUDE &&
2335             msf->imsf_fmode != MCAST_EXCLUDE)
2336                 return -EINVAL;
2337
2338         ASSERT_RTNL();
2339
2340         imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2341         imr.imr_address.s_addr = msf->imsf_interface;
2342         imr.imr_ifindex = ifindex;
2343         in_dev = ip_mc_find_dev(net, &imr);
2344
2345         if (!in_dev) {
2346                 err = -ENODEV;
2347                 goto done;
2348         }
2349
2350         /* special case - (INCLUDE, empty) == LEAVE_GROUP */
2351         if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2352                 leavegroup = 1;
2353                 goto done;
2354         }
2355
2356         for_each_pmc_rtnl(inet, pmc) {
2357                 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2358                     pmc->multi.imr_ifindex == imr.imr_ifindex)
2359                         break;
2360         }
2361         if (!pmc) {             /* must have a prior join */
2362                 err = -EINVAL;
2363                 goto done;
2364         }
2365         if (msf->imsf_numsrc) {
2366                 newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2367                                                            GFP_KERNEL);
2368                 if (!newpsl) {
2369                         err = -ENOBUFS;
2370                         goto done;
2371                 }
2372                 newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2373                 memcpy(newpsl->sl_addr, msf->imsf_slist,
2374                         msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2375                 err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2376                         msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2377                 if (err) {
2378                         sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2379                         goto done;
2380                 }
2381         } else {
2382                 newpsl = NULL;
2383                 (void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2384                                      msf->imsf_fmode, 0, NULL, 0);
2385         }
2386         psl = rtnl_dereference(pmc->sflist);
2387         if (psl) {
2388                 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2389                         psl->sl_count, psl->sl_addr, 0);
2390                 /* decrease mem now to avoid the memleak warning */
2391                 atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2392                 kfree_rcu(psl, rcu);
2393         } else
2394                 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2395                         0, NULL, 0);
2396         rcu_assign_pointer(pmc->sflist, newpsl);
2397         pmc->sfmode = msf->imsf_fmode;
2398         err = 0;
2399 done:
2400         if (leavegroup)
2401                 err = ip_mc_leave_group(sk, &imr);
2402         return err;
2403 }
2404
2405 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2406         struct ip_msfilter __user *optval, int __user *optlen)
2407 {
2408         int err, len, count, copycount;
2409         struct ip_mreqn imr;
2410         __be32 addr = msf->imsf_multiaddr;
2411         struct ip_mc_socklist *pmc;
2412         struct in_device *in_dev;
2413         struct inet_sock *inet = inet_sk(sk);
2414         struct ip_sf_socklist *psl;
2415         struct net *net = sock_net(sk);
2416
2417         ASSERT_RTNL();
2418
2419         if (!ipv4_is_multicast(addr))
2420                 return -EINVAL;
2421
2422         imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2423         imr.imr_address.s_addr = msf->imsf_interface;
2424         imr.imr_ifindex = 0;
2425         in_dev = ip_mc_find_dev(net, &imr);
2426
2427         if (!in_dev) {
2428                 err = -ENODEV;
2429                 goto done;
2430         }
2431         err = -EADDRNOTAVAIL;
2432
2433         for_each_pmc_rtnl(inet, pmc) {
2434                 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2435                     pmc->multi.imr_ifindex == imr.imr_ifindex)
2436                         break;
2437         }
2438         if (!pmc)               /* must have a prior join */
2439                 goto done;
2440         msf->imsf_fmode = pmc->sfmode;
2441         psl = rtnl_dereference(pmc->sflist);
2442         if (!psl) {
2443                 len = 0;
2444                 count = 0;
2445         } else {
2446                 count = psl->sl_count;
2447         }
2448         copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2449         len = copycount * sizeof(psl->sl_addr[0]);
2450         msf->imsf_numsrc = count;
2451         if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2452             copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2453                 return -EFAULT;
2454         }
2455         if (len &&
2456             copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2457                 return -EFAULT;
2458         return 0;
2459 done:
2460         return err;
2461 }
2462
2463 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2464         struct group_filter __user *optval, int __user *optlen)
2465 {
2466         int err, i, count, copycount;
2467         struct sockaddr_in *psin;
2468         __be32 addr;
2469         struct ip_mc_socklist *pmc;
2470         struct inet_sock *inet = inet_sk(sk);
2471         struct ip_sf_socklist *psl;
2472
2473         ASSERT_RTNL();
2474
2475         psin = (struct sockaddr_in *)&gsf->gf_group;
2476         if (psin->sin_family != AF_INET)
2477                 return -EINVAL;
2478         addr = psin->sin_addr.s_addr;
2479         if (!ipv4_is_multicast(addr))
2480                 return -EINVAL;
2481
2482         err = -EADDRNOTAVAIL;
2483
2484         for_each_pmc_rtnl(inet, pmc) {
2485                 if (pmc->multi.imr_multiaddr.s_addr == addr &&
2486                     pmc->multi.imr_ifindex == gsf->gf_interface)
2487                         break;
2488         }
2489         if (!pmc)               /* must have a prior join */
2490                 goto done;
2491         gsf->gf_fmode = pmc->sfmode;
2492         psl = rtnl_dereference(pmc->sflist);
2493         count = psl ? psl->sl_count : 0;
2494         copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2495         gsf->gf_numsrc = count;
2496         if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
2497             copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
2498                 return -EFAULT;
2499         }
2500         for (i = 0; i < copycount; i++) {
2501                 struct sockaddr_storage ss;
2502
2503                 psin = (struct sockaddr_in *)&ss;
2504                 memset(&ss, 0, sizeof(ss));
2505                 psin->sin_family = AF_INET;
2506                 psin->sin_addr.s_addr = psl->sl_addr[i];
2507                 if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
2508                         return -EFAULT;
2509         }
2510         return 0;
2511 done:
2512         return err;
2513 }
2514
2515 /*
2516  * check if a multicast source filter allows delivery for a given <src,dst,intf>
2517  */
2518 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif)
2519 {
2520         struct inet_sock *inet = inet_sk(sk);
2521         struct ip_mc_socklist *pmc;
2522         struct ip_sf_socklist *psl;
2523         int i;
2524         int ret;
2525
2526         ret = 1;
2527         if (!ipv4_is_multicast(loc_addr))
2528                 goto out;
2529
2530         rcu_read_lock();
2531         for_each_pmc_rcu(inet, pmc) {
2532                 if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2533                     pmc->multi.imr_ifindex == dif)
2534                         break;
2535         }
2536         ret = inet->mc_all;
2537         if (!pmc)
2538                 goto unlock;
2539         psl = rcu_dereference(pmc->sflist);
2540         ret = (pmc->sfmode == MCAST_EXCLUDE);
2541         if (!psl)
2542                 goto unlock;
2543
2544         for (i = 0; i < psl->sl_count; i++) {
2545                 if (psl->sl_addr[i] == rmt_addr)
2546                         break;
2547         }
2548         ret = 0;
2549         if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2550                 goto unlock;
2551         if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2552                 goto unlock;
2553         ret = 1;
2554 unlock:
2555         rcu_read_unlock();
2556 out:
2557         return ret;
2558 }
2559
2560 /*
2561  *      A socket is closing.
2562  */
2563
2564 void ip_mc_drop_socket(struct sock *sk)
2565 {
2566         struct inet_sock *inet = inet_sk(sk);
2567         struct ip_mc_socklist *iml;
2568         struct net *net = sock_net(sk);
2569
2570         if (!inet->mc_list)
2571                 return;
2572
2573         rtnl_lock();
2574         while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2575                 struct in_device *in_dev;
2576
2577                 inet->mc_list = iml->next_rcu;
2578                 in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2579                 (void) ip_mc_leave_src(sk, iml, in_dev);
2580                 if (in_dev)
2581                         ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2582                 /* decrease mem now to avoid the memleak warning */
2583                 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2584                 kfree_rcu(iml, rcu);
2585         }
2586         rtnl_unlock();
2587 }
2588
2589 /* called with rcu_read_lock() */
2590 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto)
2591 {
2592         struct ip_mc_list *im;
2593         struct ip_mc_list __rcu **mc_hash;
2594         struct ip_sf_list *psf;
2595         int rv = 0;
2596
2597         mc_hash = rcu_dereference(in_dev->mc_hash);
2598         if (mc_hash) {
2599                 u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
2600
2601                 for (im = rcu_dereference(mc_hash[hash]);
2602                      im != NULL;
2603                      im = rcu_dereference(im->next_hash)) {
2604                         if (im->multiaddr == mc_addr)
2605                                 break;
2606                 }
2607         } else {
2608                 for_each_pmc_rcu(in_dev, im) {
2609                         if (im->multiaddr == mc_addr)
2610                                 break;
2611                 }
2612         }
2613         if (im && proto == IPPROTO_IGMP) {
2614                 rv = 1;
2615         } else if (im) {
2616                 if (src_addr) {
2617                         for (psf = im->sources; psf; psf = psf->sf_next) {
2618                                 if (psf->sf_inaddr == src_addr)
2619                                         break;
2620                         }
2621                         if (psf)
2622                                 rv = psf->sf_count[MCAST_INCLUDE] ||
2623                                         psf->sf_count[MCAST_EXCLUDE] !=
2624                                         im->sfcount[MCAST_EXCLUDE];
2625                         else
2626                                 rv = im->sfcount[MCAST_EXCLUDE] != 0;
2627                 } else
2628                         rv = 1; /* unspecified source; tentatively allow */
2629         }
2630         return rv;
2631 }
2632
2633 #if defined(CONFIG_PROC_FS)
2634 struct igmp_mc_iter_state {
2635         struct seq_net_private p;
2636         struct net_device *dev;
2637         struct in_device *in_dev;
2638 };
2639
2640 #define igmp_mc_seq_private(seq)        ((struct igmp_mc_iter_state *)(seq)->private)
2641
2642 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2643 {
2644         struct net *net = seq_file_net(seq);
2645         struct ip_mc_list *im = NULL;
2646         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2647
2648         state->in_dev = NULL;
2649         for_each_netdev_rcu(net, state->dev) {
2650                 struct in_device *in_dev;
2651
2652                 in_dev = __in_dev_get_rcu(state->dev);
2653                 if (!in_dev)
2654                         continue;
2655                 im = rcu_dereference(in_dev->mc_list);
2656                 if (im) {
2657                         state->in_dev = in_dev;
2658                         break;
2659                 }
2660         }
2661         return im;
2662 }
2663
2664 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2665 {
2666         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2667
2668         im = rcu_dereference(im->next_rcu);
2669         while (!im) {
2670                 state->dev = next_net_device_rcu(state->dev);
2671                 if (!state->dev) {
2672                         state->in_dev = NULL;
2673                         break;
2674                 }
2675                 state->in_dev = __in_dev_get_rcu(state->dev);
2676                 if (!state->in_dev)
2677                         continue;
2678                 im = rcu_dereference(state->in_dev->mc_list);
2679         }
2680         return im;
2681 }
2682
2683 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2684 {
2685         struct ip_mc_list *im = igmp_mc_get_first(seq);
2686         if (im)
2687                 while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2688                         --pos;
2689         return pos ? NULL : im;
2690 }
2691
2692 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2693         __acquires(rcu)
2694 {
2695         rcu_read_lock();
2696         return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2697 }
2698
2699 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2700 {
2701         struct ip_mc_list *im;
2702         if (v == SEQ_START_TOKEN)
2703                 im = igmp_mc_get_first(seq);
2704         else
2705                 im = igmp_mc_get_next(seq, v);
2706         ++*pos;
2707         return im;
2708 }
2709
2710 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2711         __releases(rcu)
2712 {
2713         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2714
2715         state->in_dev = NULL;
2716         state->dev = NULL;
2717         rcu_read_unlock();
2718 }
2719
2720 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2721 {
2722         if (v == SEQ_START_TOKEN)
2723                 seq_puts(seq,
2724                          "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2725         else {
2726                 struct ip_mc_list *im = (struct ip_mc_list *)v;
2727                 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2728                 char   *querier;
2729                 long delta;
2730
2731 #ifdef CONFIG_IP_MULTICAST
2732                 querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2733                           IGMP_V2_SEEN(state->in_dev) ? "V2" :
2734                           "V3";
2735 #else
2736                 querier = "NONE";
2737 #endif
2738
2739                 if (rcu_access_pointer(state->in_dev->mc_list) == im) {
2740                         seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2741                                    state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2742                 }
2743
2744                 delta = im->timer.expires - jiffies;
2745                 seq_printf(seq,
2746                            "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2747                            im->multiaddr, im->users,
2748                            im->tm_running,
2749                            im->tm_running ? jiffies_delta_to_clock_t(delta) : 0,
2750                            im->reporter);
2751         }
2752         return 0;
2753 }
2754
2755 static const struct seq_operations igmp_mc_seq_ops = {
2756         .start  =       igmp_mc_seq_start,
2757         .next   =       igmp_mc_seq_next,
2758         .stop   =       igmp_mc_seq_stop,
2759         .show   =       igmp_mc_seq_show,
2760 };
2761
2762 static int igmp_mc_seq_open(struct inode *inode, struct file *file)
2763 {
2764         return seq_open_net(inode, file, &igmp_mc_seq_ops,
2765                         sizeof(struct igmp_mc_iter_state));
2766 }
2767
2768 static const struct file_operations igmp_mc_seq_fops = {
2769         .owner          =       THIS_MODULE,
2770         .open           =       igmp_mc_seq_open,
2771         .read           =       seq_read,
2772         .llseek         =       seq_lseek,
2773         .release        =       seq_release_net,
2774 };
2775
2776 struct igmp_mcf_iter_state {
2777         struct seq_net_private p;
2778         struct net_device *dev;
2779         struct in_device *idev;
2780         struct ip_mc_list *im;
2781 };
2782
2783 #define igmp_mcf_seq_private(seq)       ((struct igmp_mcf_iter_state *)(seq)->private)
2784
2785 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2786 {
2787         struct net *net = seq_file_net(seq);
2788         struct ip_sf_list *psf = NULL;
2789         struct ip_mc_list *im = NULL;
2790         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2791
2792         state->idev = NULL;
2793         state->im = NULL;
2794         for_each_netdev_rcu(net, state->dev) {
2795                 struct in_device *idev;
2796                 idev = __in_dev_get_rcu(state->dev);
2797                 if (unlikely(!idev))
2798                         continue;
2799                 im = rcu_dereference(idev->mc_list);
2800                 if (likely(im)) {
2801                         spin_lock_bh(&im->lock);
2802                         psf = im->sources;
2803                         if (likely(psf)) {
2804                                 state->im = im;
2805                                 state->idev = idev;
2806                                 break;
2807                         }
2808                         spin_unlock_bh(&im->lock);
2809                 }
2810         }
2811         return psf;
2812 }
2813
2814 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2815 {
2816         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2817
2818         psf = psf->sf_next;
2819         while (!psf) {
2820                 spin_unlock_bh(&state->im->lock);
2821                 state->im = state->im->next;
2822                 while (!state->im) {
2823                         state->dev = next_net_device_rcu(state->dev);
2824                         if (!state->dev) {
2825                                 state->idev = NULL;
2826                                 goto out;
2827                         }
2828                         state->idev = __in_dev_get_rcu(state->dev);
2829                         if (!state->idev)
2830                                 continue;
2831                         state->im = rcu_dereference(state->idev->mc_list);
2832                 }
2833                 if (!state->im)
2834                         break;
2835                 spin_lock_bh(&state->im->lock);
2836                 psf = state->im->sources;
2837         }
2838 out:
2839         return psf;
2840 }
2841
2842 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2843 {
2844         struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2845         if (psf)
2846                 while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2847                         --pos;
2848         return pos ? NULL : psf;
2849 }
2850
2851 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2852         __acquires(rcu)
2853 {
2854         rcu_read_lock();
2855         return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2856 }
2857
2858 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2859 {
2860         struct ip_sf_list *psf;
2861         if (v == SEQ_START_TOKEN)
2862                 psf = igmp_mcf_get_first(seq);
2863         else
2864                 psf = igmp_mcf_get_next(seq, v);
2865         ++*pos;
2866         return psf;
2867 }
2868
2869 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2870         __releases(rcu)
2871 {
2872         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2873         if (likely(state->im)) {
2874                 spin_unlock_bh(&state->im->lock);
2875                 state->im = NULL;
2876         }
2877         state->idev = NULL;
2878         state->dev = NULL;
2879         rcu_read_unlock();
2880 }
2881
2882 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2883 {
2884         struct ip_sf_list *psf = (struct ip_sf_list *)v;
2885         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2886
2887         if (v == SEQ_START_TOKEN) {
2888                 seq_puts(seq, "Idx Device        MCA        SRC    INC    EXC\n");
2889         } else {
2890                 seq_printf(seq,
2891                            "%3d %6.6s 0x%08x "
2892                            "0x%08x %6lu %6lu\n",
2893                            state->dev->ifindex, state->dev->name,
2894                            ntohl(state->im->multiaddr),
2895                            ntohl(psf->sf_inaddr),
2896                            psf->sf_count[MCAST_INCLUDE],
2897                            psf->sf_count[MCAST_EXCLUDE]);
2898         }
2899         return 0;
2900 }
2901
2902 static const struct seq_operations igmp_mcf_seq_ops = {
2903         .start  =       igmp_mcf_seq_start,
2904         .next   =       igmp_mcf_seq_next,
2905         .stop   =       igmp_mcf_seq_stop,
2906         .show   =       igmp_mcf_seq_show,
2907 };
2908
2909 static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
2910 {
2911         return seq_open_net(inode, file, &igmp_mcf_seq_ops,
2912                         sizeof(struct igmp_mcf_iter_state));
2913 }
2914
2915 static const struct file_operations igmp_mcf_seq_fops = {
2916         .owner          =       THIS_MODULE,
2917         .open           =       igmp_mcf_seq_open,
2918         .read           =       seq_read,
2919         .llseek         =       seq_lseek,
2920         .release        =       seq_release_net,
2921 };
2922
2923 static int __net_init igmp_net_init(struct net *net)
2924 {
2925         struct proc_dir_entry *pde;
2926         int err;
2927
2928         pde = proc_create("igmp", S_IRUGO, net->proc_net, &igmp_mc_seq_fops);
2929         if (!pde)
2930                 goto out_igmp;
2931         pde = proc_create("mcfilter", S_IRUGO, net->proc_net,
2932                           &igmp_mcf_seq_fops);
2933         if (!pde)
2934                 goto out_mcfilter;
2935         err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET,
2936                                    SOCK_DGRAM, 0, net);
2937         if (err < 0) {
2938                 pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n",
2939                        err);
2940                 goto out_sock;
2941         }
2942
2943         /* Sysctl initialization */
2944         net->ipv4.sysctl_igmp_max_memberships = 20;
2945         net->ipv4.sysctl_igmp_max_msf = 10;
2946         /* IGMP reports for link-local multicast groups are enabled by default */
2947         net->ipv4.sysctl_igmp_llm_reports = 1;
2948         net->ipv4.sysctl_igmp_qrv = 2;
2949         return 0;
2950
2951 out_sock:
2952         remove_proc_entry("mcfilter", net->proc_net);
2953 out_mcfilter:
2954         remove_proc_entry("igmp", net->proc_net);
2955 out_igmp:
2956         return -ENOMEM;
2957 }
2958
2959 static void __net_exit igmp_net_exit(struct net *net)
2960 {
2961         remove_proc_entry("mcfilter", net->proc_net);
2962         remove_proc_entry("igmp", net->proc_net);
2963         inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk);
2964 }
2965
2966 static struct pernet_operations igmp_net_ops = {
2967         .init = igmp_net_init,
2968         .exit = igmp_net_exit,
2969 };
2970 #endif
2971
2972 static int igmp_netdev_event(struct notifier_block *this,
2973                              unsigned long event, void *ptr)
2974 {
2975         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2976         struct in_device *in_dev;
2977
2978         switch (event) {
2979         case NETDEV_RESEND_IGMP:
2980                 in_dev = __in_dev_get_rtnl(dev);
2981                 if (in_dev)
2982                         ip_mc_rejoin_groups(in_dev);
2983                 break;
2984         default:
2985                 break;
2986         }
2987         return NOTIFY_DONE;
2988 }
2989
2990 static struct notifier_block igmp_notifier = {
2991         .notifier_call = igmp_netdev_event,
2992 };
2993
2994 int __init igmp_mc_init(void)
2995 {
2996 #if defined(CONFIG_PROC_FS)
2997         int err;
2998
2999         err = register_pernet_subsys(&igmp_net_ops);
3000         if (err)
3001                 return err;
3002         err = register_netdevice_notifier(&igmp_notifier);
3003         if (err)
3004                 goto reg_notif_fail;
3005         return 0;
3006
3007 reg_notif_fail:
3008         unregister_pernet_subsys(&igmp_net_ops);
3009         return err;
3010 #else
3011         return register_netdevice_notifier(&igmp_notifier);
3012 #endif
3013 }