net/ipv4/igmp.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *      Linux NET3:     Internet Group Management Protocol  [IGMP]
   4  *
   5  *      This code implements the IGMP protocol as defined in RFC1112. There has
   6  *      been a further revision of this protocol since which is now supported.
   7  *
   8  *      If you have trouble with this module be careful what gcc you have used,
   9  *      the older version didn't come out right using gcc 2.5.8, the newer one
  10  *      seems to fall out with gcc 2.6.2.
  11  *
  12  *      Authors:
  13  *              Alan Cox <alan@lxorguk.ukuu.org.uk>
  14  *
  15  *      Fixes:
  16  *
  17  *              Alan Cox        :       Added lots of __inline__ to optimise
  18  *                                      the memory usage of all the tiny little
  19  *                                      functions.
  20  *              Alan Cox        :       Dumped the header building experiment.
  21  *              Alan Cox        :       Minor tweaks ready for multicast routing
  22  *                                      and extended IGMP protocol.
  23  *              Alan Cox        :       Removed a load of inline directives. Gcc 2.5.8
  24  *                                      writes utterly bogus code otherwise (sigh)
  25  *                                      fixed IGMP loopback to behave in the manner
  26  *                                      desired by mrouted, fixed the fact it has been
  27  *                                      broken since 1.3.6 and cleaned up a few minor
  28  *                                      points.
  29  *
  30  *              Chih-Jen Chang  :       Tried to revise IGMP to Version 2
  31  *              Tsu-Sheng Tsao          E-mail: chihjenc@scf.usc.edu and tsusheng@scf.usc.edu
  32  *                                      The enhancements are mainly based on Steve Deering's
  33  *                                      ipmulti-3.5 source code.
  34  *              Chih-Jen Chang  :       Added the igmp_get_mrouter_info and
  35  *              Tsu-Sheng Tsao          igmp_set_mrouter_info to keep track of
  36  *                                      the mrouted version on that device.
  37  *              Chih-Jen Chang  :       Added the max_resp_time parameter to
  38  *              Tsu-Sheng Tsao          igmp_heard_query(). Using this parameter
  39  *                                      to identify the multicast router version
  40  *                                      and do what the IGMP version 2 specified.
  41  *              Chih-Jen Chang  :       Added a timer to revert to IGMP V2 router
  42  *              Tsu-Sheng Tsao          if the specified time expired.
  43  *              Alan Cox        :       Stop IGMP from 0.0.0.0 being accepted.
  44  *              Alan Cox        :       Use GFP_ATOMIC in the right places.
  45  *              Christian Daudt :       igmp timer wasn't set for local group
  46  *                                      memberships but was being deleted,
  47  *                                      which caused a "del_timer() called
  48  *                                      from %p with timer not initialized\n"
  49  *                                      message (960131).
  50  *              Christian Daudt :       removed del_timer from
  51  *                                      igmp_timer_expire function (960205).
  52  *             Christian Daudt :       igmp_heard_report now only calls
  53  *                                     igmp_timer_expire if tm->running is
  54  *                                     true (960216).
  55  *              Malcolm Beattie :       ttl comparison wrong in igmp_rcv made
  56  *                                      igmp_heard_query never trigger. Expiry
  57  *                                      miscalculation fixed in igmp_heard_query
  58  *                                      and random() made to return unsigned to
  59  *                                      prevent negative expiry times.
  60  *              Alexey Kuznetsov:       Wrong group leaving behaviour, backport
  61  *                                      fix from pending 2.1.x patches.
  62  *              Alan Cox:               Forget to enable FDDI support earlier.
  63  *              Alexey Kuznetsov:       Fixed leaving groups on device down.
  64  *              Alexey Kuznetsov:       Accordance to igmp-v2-06 draft.
  65  *              David L Stevens:        IGMPv3 support, with help from
  66  *                                      Vinay Kulkarni
  67  */
  68
  69 #include <linux/module.h>
  70 #include <linux/slab.h>
  71 #include <linux/uaccess.h>
  72 #include <linux/types.h>
  73 #include <linux/kernel.h>
  74 #include <linux/jiffies.h>
  75 #include <linux/string.h>
  76 #include <linux/socket.h>
  77 #include <linux/sockios.h>
  78 #include <linux/in.h>
  79 #include <linux/inet.h>
  80 #include <linux/netdevice.h>
  81 #include <linux/skbuff.h>
  82 #include <linux/inetdevice.h>
  83 #include <linux/igmp.h>
  84 #include <linux/if_arp.h>
  85 #include <linux/rtnetlink.h>
  86 #include <linux/times.h>
  87 #include <linux/pkt_sched.h>
  88 #include <linux/byteorder/generic.h>
  89
  90 #include <net/net_namespace.h>
  91 #include <net/arp.h>
  92 #include <net/ip.h>
  93 #include <net/protocol.h>
  94 #include <net/route.h>
  95 #include <net/sock.h>
  96 #include <net/checksum.h>
  97 #include <net/inet_common.h>
  98 #include <linux/netfilter_ipv4.h>
  99 #ifdef CONFIG_IP_MROUTE
 100 #include <linux/mroute.h>
 101 #endif
 102 #ifdef CONFIG_PROC_FS
 103 #include <linux/proc_fs.h>
 104 #include <linux/seq_file.h>
 105 #endif
 106
 107 #ifdef CONFIG_IP_MULTICAST
 108 /* Parameter names and values are taken from igmp-v2-06 draft */
 109
 110 #define IGMP_QUERY_INTERVAL                     (125*HZ)
 111 #define IGMP_QUERY_RESPONSE_INTERVAL            (10*HZ)
 112
 113 #define IGMP_INITIAL_REPORT_DELAY               (1)
 114
 115 /* IGMP_INITIAL_REPORT_DELAY is not from IGMP specs!
 116  * IGMP specs require to report membership immediately after
 117  * joining a group, but we delay the first report by a
 118  * small interval. It seems more natural and still does not
 119  * contradict to specs provided this delay is small enough.
 120  */
 121
 122 #define IGMP_V1_SEEN(in_dev) \
 123         (IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \
 124          IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \
 125          ((in_dev)->mr_v1_seen && \
 126           time_before(jiffies, (in_dev)->mr_v1_seen)))
 127 #define IGMP_V2_SEEN(in_dev) \
 128         (IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \
 129          IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \
 130          ((in_dev)->mr_v2_seen && \
 131           time_before(jiffies, (in_dev)->mr_v2_seen)))
 132
 133 static int unsolicited_report_interval(struct in_device *in_dev)
 134 {
 135         int interval_ms, interval_jiffies;
 136
 137         if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 138                 interval_ms = IN_DEV_CONF_GET(
 139                         in_dev,
 140                         IGMPV2_UNSOLICITED_REPORT_INTERVAL);
 141         else /* v3 */
 142                 interval_ms = IN_DEV_CONF_GET(
 143                         in_dev,
 144                         IGMPV3_UNSOLICITED_REPORT_INTERVAL);
 145
 146         interval_jiffies = msecs_to_jiffies(interval_ms);
 147
 148         /* _timer functions can't handle a delay of 0 jiffies so ensure
 149          *  we always return a positive value.
 150          */
 151         if (interval_jiffies <= 0)
 152                 interval_jiffies = 1;
 153         return interval_jiffies;
 154 }
 155
 156 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im,
 157                               gfp_t gfp);
 158 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im);
 159 static void igmpv3_clear_delrec(struct in_device *in_dev);
 160 static int sf_setstate(struct ip_mc_list *pmc);
 161 static void sf_markstate(struct ip_mc_list *pmc);
 162 #endif
 163 static void ip_mc_clear_src(struct ip_mc_list *pmc);
 164 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
 165                          int sfcount, __be32 *psfsrc, int delta);
 166
 167 static void ip_ma_put(struct ip_mc_list *im)
 168 {
 169         if (refcount_dec_and_test(&im->refcnt)) {
 170                 in_dev_put(im->interface);
 171                 kfree_rcu(im, rcu);
 172         }
 173 }
 174
 175 #define for_each_pmc_rcu(in_dev, pmc)                           \
 176         for (pmc = rcu_dereference(in_dev->mc_list);            \
 177              pmc != NULL;                                       \
 178              pmc = rcu_dereference(pmc->next_rcu))
 179
 180 #define for_each_pmc_rtnl(in_dev, pmc)                          \
 181         for (pmc = rtnl_dereference(in_dev->mc_list);           \
 182              pmc != NULL;                                       \
 183              pmc = rtnl_dereference(pmc->next_rcu))
 184
 185 static void ip_sf_list_clear_all(struct ip_sf_list *psf)
 186 {
 187         struct ip_sf_list *next;
 188
 189         while (psf) {
 190                 next = psf->sf_next;
 191                 kfree(psf);
 192                 psf = next;
 193         }
 194 }
 195
 196 #ifdef CONFIG_IP_MULTICAST
 197
 198 /*
 199  *      Timer management
 200  */
 201
 202 static void igmp_stop_timer(struct ip_mc_list *im)
 203 {
 204         spin_lock_bh(&im->lock);
 205         if (del_timer(&im->timer))
 206                 refcount_dec(&im->refcnt);
 207         im->tm_running = 0;
 208         im->reporter = 0;
 209         im->unsolicit_count = 0;
 210         spin_unlock_bh(&im->lock);
 211 }
 212
 213 /* It must be called with locked im->lock */
 214 static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
 215 {
 216         int tv = prandom_u32() % max_delay;
 217
 218         im->tm_running = 1;
 219         if (!mod_timer(&im->timer, jiffies+tv+2))
 220                 refcount_inc(&im->refcnt);
 221 }
 222
 223 static void igmp_gq_start_timer(struct in_device *in_dev)
 224 {
 225         int tv = prandom_u32() % in_dev->mr_maxdelay;
 226         unsigned long exp = jiffies + tv + 2;
 227
 228         if (in_dev->mr_gq_running &&
 229             time_after_eq(exp, (in_dev->mr_gq_timer).expires))
 230                 return;
 231
 232         in_dev->mr_gq_running = 1;
 233         if (!mod_timer(&in_dev->mr_gq_timer, exp))
 234                 in_dev_hold(in_dev);
 235 }
 236
 237 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
 238 {
 239         int tv = prandom_u32() % delay;
 240
 241         if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
 242                 in_dev_hold(in_dev);
 243 }
 244
 245 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
 246 {
 247         spin_lock_bh(&im->lock);
 248         im->unsolicit_count = 0;
 249         if (del_timer(&im->timer)) {
 250                 if ((long)(im->timer.expires-jiffies) < max_delay) {
 251                         add_timer(&im->timer);
 252                         im->tm_running = 1;
 253                         spin_unlock_bh(&im->lock);
 254                         return;
 255                 }
 256                 refcount_dec(&im->refcnt);
 257         }
 258         igmp_start_timer(im, max_delay);
 259         spin_unlock_bh(&im->lock);
 260 }
 261
 262
 263 /*
 264  *      Send an IGMP report.
 265  */
 266
 267 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
 268
 269
 270 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
 271         int gdeleted, int sdeleted)
 272 {
 273         switch (type) {
 274         case IGMPV3_MODE_IS_INCLUDE:
 275         case IGMPV3_MODE_IS_EXCLUDE:
 276                 if (gdeleted || sdeleted)
 277                         return 0;
 278                 if (!(pmc->gsquery && !psf->sf_gsresp)) {
 279                         if (pmc->sfmode == MCAST_INCLUDE)
 280                                 return 1;
 281                         /* don't include if this source is excluded
 282                          * in all filters
 283                          */
 284                         if (psf->sf_count[MCAST_INCLUDE])
 285                                 return type == IGMPV3_MODE_IS_INCLUDE;
 286                         return pmc->sfcount[MCAST_EXCLUDE] ==
 287                                 psf->sf_count[MCAST_EXCLUDE];
 288                 }
 289                 return 0;
 290         case IGMPV3_CHANGE_TO_INCLUDE:
 291                 if (gdeleted || sdeleted)
 292                         return 0;
 293                 return psf->sf_count[MCAST_INCLUDE] != 0;
 294         case IGMPV3_CHANGE_TO_EXCLUDE:
 295                 if (gdeleted || sdeleted)
 296                         return 0;
 297                 if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
 298                     psf->sf_count[MCAST_INCLUDE])
 299                         return 0;
 300                 return pmc->sfcount[MCAST_EXCLUDE] ==
 301                         psf->sf_count[MCAST_EXCLUDE];
 302         case IGMPV3_ALLOW_NEW_SOURCES:
 303                 if (gdeleted || !psf->sf_crcount)
 304                         return 0;
 305                 return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
 306         case IGMPV3_BLOCK_OLD_SOURCES:
 307                 if (pmc->sfmode == MCAST_INCLUDE)
 308                         return gdeleted || (psf->sf_crcount && sdeleted);
 309                 return psf->sf_crcount && !gdeleted && !sdeleted;
 310         }
 311         return 0;
 312 }
 313
 314 static int
 315 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
 316 {
 317         struct ip_sf_list *psf;
 318         int scount = 0;
 319
 320         for (psf = pmc->sources; psf; psf = psf->sf_next) {
 321                 if (!is_in(pmc, psf, type, gdeleted, sdeleted))
 322                         continue;
 323                 scount++;
 324         }
 325         return scount;
 326 }
 327
 328 /* source address selection per RFC 3376 section 4.2.13 */
 329 static __be32 igmpv3_get_srcaddr(struct net_device *dev,
 330                                  const struct flowi4 *fl4)
 331 {
 332         struct in_device *in_dev = __in_dev_get_rcu(dev);
 333         const struct in_ifaddr *ifa;
 334
 335         if (!in_dev)
 336                 return htonl(INADDR_ANY);
 337
 338         in_dev_for_each_ifa_rcu(ifa, in_dev) {
 339                 if (fl4->saddr == ifa->ifa_local)
 340                         return fl4->saddr;
 341         }
 342
 343         return htonl(INADDR_ANY);
 344 }
 345
 346 static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
 347 {
 348         struct sk_buff *skb;
 349         struct rtable *rt;
 350         struct iphdr *pip;
 351         struct igmpv3_report *pig;
 352         struct net *net = dev_net(dev);
 353         struct flowi4 fl4;
 354         int hlen = LL_RESERVED_SPACE(dev);
 355         int tlen = dev->needed_tailroom;
 356         unsigned int size = mtu;
 357
 358         while (1) {
 359                 skb = alloc_skb(size + hlen + tlen,
 360                                 GFP_ATOMIC | __GFP_NOWARN);
 361                 if (skb)
 362                         break;
 363                 size >>= 1;
 364                 if (size < 256)
 365                         return NULL;
 366         }
 367         skb->priority = TC_PRIO_CONTROL;
 368
 369         rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0,
 370                                    0, 0,
 371                                    IPPROTO_IGMP, 0, dev->ifindex);
 372         if (IS_ERR(rt)) {
 373                 kfree_skb(skb);
 374                 return NULL;
 375         }
 376
 377         skb_dst_set(skb, &rt->dst);
 378         skb->dev = dev;
 379
 380         skb_reserve(skb, hlen);
 381         skb_tailroom_reserve(skb, mtu, tlen);
 382
 383         skb_reset_network_header(skb);
 384         pip = ip_hdr(skb);
 385         skb_put(skb, sizeof(struct iphdr) + 4);
 386
 387         pip->version  = 4;
 388         pip->ihl      = (sizeof(struct iphdr)+4)>>2;
 389         pip->tos      = 0xc0;
 390         pip->frag_off = htons(IP_DF);
 391         pip->ttl      = 1;
 392         pip->daddr    = fl4.daddr;
 393
 394         rcu_read_lock();
 395         pip->saddr    = igmpv3_get_srcaddr(dev, &fl4);
 396         rcu_read_unlock();
 397
 398         pip->protocol = IPPROTO_IGMP;
 399         pip->tot_len  = 0;      /* filled in later */
 400         ip_select_ident(net, skb, NULL);
 401         ((u8 *)&pip[1])[0] = IPOPT_RA;
 402         ((u8 *)&pip[1])[1] = 4;
 403         ((u8 *)&pip[1])[2] = 0;
 404         ((u8 *)&pip[1])[3] = 0;
 405
 406         skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
 407         skb_put(skb, sizeof(*pig));
 408         pig = igmpv3_report_hdr(skb);
 409         pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
 410         pig->resv1 = 0;
 411         pig->csum = 0;
 412         pig->resv2 = 0;
 413         pig->ngrec = 0;
 414         return skb;
 415 }
 416
 417 static int igmpv3_sendpack(struct sk_buff *skb)
 418 {
 419         struct igmphdr *pig = igmp_hdr(skb);
 420         const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
 421
 422         pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
 423
 424         return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
 425 }
 426
 427 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
 428 {
 429         return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
 430 }
 431
 432 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
 433         int type, struct igmpv3_grec **ppgr, unsigned int mtu)
 434 {
 435         struct net_device *dev = pmc->interface->dev;
 436         struct igmpv3_report *pih;
 437         struct igmpv3_grec *pgr;
 438
 439         if (!skb) {
 440                 skb = igmpv3_newpack(dev, mtu);
 441                 if (!skb)
 442                         return NULL;
 443         }
 444         pgr = skb_put(skb, sizeof(struct igmpv3_grec));
 445         pgr->grec_type = type;
 446         pgr->grec_auxwords = 0;
 447         pgr->grec_nsrcs = 0;
 448         pgr->grec_mca = pmc->multiaddr;
 449         pih = igmpv3_report_hdr(skb);
 450         pih->ngrec = htons(ntohs(pih->ngrec)+1);
 451         *ppgr = pgr;
 452         return skb;
 453 }
 454
 455 #define AVAILABLE(skb)  ((skb) ? skb_availroom(skb) : 0)
 456
 457 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
 458         int type, int gdeleted, int sdeleted)
 459 {
 460         struct net_device *dev = pmc->interface->dev;
 461         struct net *net = dev_net(dev);
 462         struct igmpv3_report *pih;
 463         struct igmpv3_grec *pgr = NULL;
 464         struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
 465         int scount, stotal, first, isquery, truncate;
 466         unsigned int mtu;
 467
 468         if (pmc->multiaddr == IGMP_ALL_HOSTS)
 469                 return skb;
 470         if (ipv4_is_local_multicast(pmc->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
 471                 return skb;
 472
 473         mtu = READ_ONCE(dev->mtu);
 474         if (mtu < IPV4_MIN_MTU)
 475                 return skb;
 476
 477         isquery = type == IGMPV3_MODE_IS_INCLUDE ||
 478                   type == IGMPV3_MODE_IS_EXCLUDE;
 479         truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
 480                     type == IGMPV3_CHANGE_TO_EXCLUDE;
 481
 482         stotal = scount = 0;
 483
 484         psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
 485
 486         if (!*psf_list)
 487                 goto empty_source;
 488
 489         pih = skb ? igmpv3_report_hdr(skb) : NULL;
 490
 491         /* EX and TO_EX get a fresh packet, if needed */
 492         if (truncate) {
 493                 if (pih && pih->ngrec &&
 494                     AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
 495                         if (skb)
 496                                 igmpv3_sendpack(skb);
 497                         skb = igmpv3_newpack(dev, mtu);
 498                 }
 499         }
 500         first = 1;
 501         psf_prev = NULL;
 502         for (psf = *psf_list; psf; psf = psf_next) {
 503                 __be32 *psrc;
 504
 505                 psf_next = psf->sf_next;
 506
 507                 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
 508                         psf_prev = psf;
 509                         continue;
 510                 }
 511
 512                 /* Based on RFC3376 5.1. Should not send source-list change
 513                  * records when there is a filter mode change.
 514                  */
 515                 if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) ||
 516                      (!gdeleted && pmc->crcount)) &&
 517                     (type == IGMPV3_ALLOW_NEW_SOURCES ||
 518                      type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount)
 519                         goto decrease_sf_crcount;
 520
 521                 /* clear marks on query responses */
 522                 if (isquery)
 523                         psf->sf_gsresp = 0;
 524
 525                 if (AVAILABLE(skb) < sizeof(__be32) +
 526                     first*sizeof(struct igmpv3_grec)) {
 527                         if (truncate && !first)
 528                                 break;   /* truncate these */
 529                         if (pgr)
 530                                 pgr->grec_nsrcs = htons(scount);
 531                         if (skb)
 532                                 igmpv3_sendpack(skb);
 533                         skb = igmpv3_newpack(dev, mtu);
 534                         first = 1;
 535                         scount = 0;
 536                 }
 537                 if (first) {
 538                         skb = add_grhead(skb, pmc, type, &pgr, mtu);
 539                         first = 0;
 540                 }
 541                 if (!skb)
 542                         return NULL;
 543                 psrc = skb_put(skb, sizeof(__be32));
 544                 *psrc = psf->sf_inaddr;
 545                 scount++; stotal++;
 546                 if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
 547                      type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
 548 decrease_sf_crcount:
 549                         psf->sf_crcount--;
 550                         if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
 551                                 if (psf_prev)
 552                                         psf_prev->sf_next = psf->sf_next;
 553                                 else
 554                                         *psf_list = psf->sf_next;
 555                                 kfree(psf);
 556                                 continue;
 557                         }
 558                 }
 559                 psf_prev = psf;
 560         }
 561
 562 empty_source:
 563         if (!stotal) {
 564                 if (type == IGMPV3_ALLOW_NEW_SOURCES ||
 565                     type == IGMPV3_BLOCK_OLD_SOURCES)
 566                         return skb;
 567                 if (pmc->crcount || isquery) {
 568                         /* make sure we have room for group header */
 569                         if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) {
 570                                 igmpv3_sendpack(skb);
 571                                 skb = NULL; /* add_grhead will get a new one */
 572                         }
 573                         skb = add_grhead(skb, pmc, type, &pgr, mtu);
 574                 }
 575         }
 576         if (pgr)
 577                 pgr->grec_nsrcs = htons(scount);
 578
 579         if (isquery)
 580                 pmc->gsquery = 0;       /* clear query state on report */
 581         return skb;
 582 }
 583
 584 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
 585 {
 586         struct sk_buff *skb = NULL;
 587         struct net *net = dev_net(in_dev->dev);
 588         int type;
 589
 590         if (!pmc) {
 591                 rcu_read_lock();
 592                 for_each_pmc_rcu(in_dev, pmc) {
 593                         if (pmc->multiaddr == IGMP_ALL_HOSTS)
 594                                 continue;
 595                         if (ipv4_is_local_multicast(pmc->multiaddr) &&
 596                              !net->ipv4.sysctl_igmp_llm_reports)
 597                                 continue;
 598                         spin_lock_bh(&pmc->lock);
 599                         if (pmc->sfcount[MCAST_EXCLUDE])
 600                                 type = IGMPV3_MODE_IS_EXCLUDE;
 601                         else
 602                                 type = IGMPV3_MODE_IS_INCLUDE;
 603                         skb = add_grec(skb, pmc, type, 0, 0);
 604                         spin_unlock_bh(&pmc->lock);
 605                 }
 606                 rcu_read_unlock();
 607         } else {
 608                 spin_lock_bh(&pmc->lock);
 609                 if (pmc->sfcount[MCAST_EXCLUDE])
 610                         type = IGMPV3_MODE_IS_EXCLUDE;
 611                 else
 612                         type = IGMPV3_MODE_IS_INCLUDE;
 613                 skb = add_grec(skb, pmc, type, 0, 0);
 614                 spin_unlock_bh(&pmc->lock);
 615         }
 616         if (!skb)
 617                 return 0;
 618         return igmpv3_sendpack(skb);
 619 }
 620
 621 /*
 622  * remove zero-count source records from a source filter list
 623  */
 624 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
 625 {
 626         struct ip_sf_list *psf_prev, *psf_next, *psf;
 627
 628         psf_prev = NULL;
 629         for (psf = *ppsf; psf; psf = psf_next) {
 630                 psf_next = psf->sf_next;
 631                 if (psf->sf_crcount == 0) {
 632                         if (psf_prev)
 633                                 psf_prev->sf_next = psf->sf_next;
 634                         else
 635                                 *ppsf = psf->sf_next;
 636                         kfree(psf);
 637                 } else
 638                         psf_prev = psf;
 639         }
 640 }
 641
 642 static void kfree_pmc(struct ip_mc_list *pmc)
 643 {
 644         ip_sf_list_clear_all(pmc->sources);
 645         ip_sf_list_clear_all(pmc->tomb);
 646         kfree(pmc);
 647 }
 648
 649 static void igmpv3_send_cr(struct in_device *in_dev)
 650 {
 651         struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
 652         struct sk_buff *skb = NULL;
 653         int type, dtype;
 654
 655         rcu_read_lock();
 656         spin_lock_bh(&in_dev->mc_tomb_lock);
 657
 658         /* deleted MCA's */
 659         pmc_prev = NULL;
 660         for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) {
 661                 pmc_next = pmc->next;
 662                 if (pmc->sfmode == MCAST_INCLUDE) {
 663                         type = IGMPV3_BLOCK_OLD_SOURCES;
 664                         dtype = IGMPV3_BLOCK_OLD_SOURCES;
 665                         skb = add_grec(skb, pmc, type, 1, 0);
 666                         skb = add_grec(skb, pmc, dtype, 1, 1);
 667                 }
 668                 if (pmc->crcount) {
 669                         if (pmc->sfmode == MCAST_EXCLUDE) {
 670                                 type = IGMPV3_CHANGE_TO_INCLUDE;
 671                                 skb = add_grec(skb, pmc, type, 1, 0);
 672                         }
 673                         pmc->crcount--;
 674                         if (pmc->crcount == 0) {
 675                                 igmpv3_clear_zeros(&pmc->tomb);
 676                                 igmpv3_clear_zeros(&pmc->sources);
 677                         }
 678                 }
 679                 if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
 680                         if (pmc_prev)
 681                                 pmc_prev->next = pmc_next;
 682                         else
 683                                 in_dev->mc_tomb = pmc_next;
 684                         in_dev_put(pmc->interface);
 685                         kfree_pmc(pmc);
 686                 } else
 687                         pmc_prev = pmc;
 688         }
 689         spin_unlock_bh(&in_dev->mc_tomb_lock);
 690
 691         /* change recs */
 692         for_each_pmc_rcu(in_dev, pmc) {
 693                 spin_lock_bh(&pmc->lock);
 694                 if (pmc->sfcount[MCAST_EXCLUDE]) {
 695                         type = IGMPV3_BLOCK_OLD_SOURCES;
 696                         dtype = IGMPV3_ALLOW_NEW_SOURCES;
 697                 } else {
 698                         type = IGMPV3_ALLOW_NEW_SOURCES;
 699                         dtype = IGMPV3_BLOCK_OLD_SOURCES;
 700                 }
 701                 skb = add_grec(skb, pmc, type, 0, 0);
 702                 skb = add_grec(skb, pmc, dtype, 0, 1);  /* deleted sources */
 703
 704                 /* filter mode changes */
 705                 if (pmc->crcount) {
 706                         if (pmc->sfmode == MCAST_EXCLUDE)
 707                                 type = IGMPV3_CHANGE_TO_EXCLUDE;
 708                         else
 709                                 type = IGMPV3_CHANGE_TO_INCLUDE;
 710                         skb = add_grec(skb, pmc, type, 0, 0);
 711                         pmc->crcount--;
 712                 }
 713                 spin_unlock_bh(&pmc->lock);
 714         }
 715         rcu_read_unlock();
 716
 717         if (!skb)
 718                 return;
 719         (void) igmpv3_sendpack(skb);
 720 }
 721
 722 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
 723         int type)
 724 {
 725         struct sk_buff *skb;
 726         struct iphdr *iph;
 727         struct igmphdr *ih;
 728         struct rtable *rt;
 729         struct net_device *dev = in_dev->dev;
 730         struct net *net = dev_net(dev);
 731         __be32  group = pmc ? pmc->multiaddr : 0;
 732         struct flowi4 fl4;
 733         __be32  dst;
 734         int hlen, tlen;
 735
 736         if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
 737                 return igmpv3_send_report(in_dev, pmc);
 738
 739         if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
 740                 return 0;
 741
 742         if (type == IGMP_HOST_LEAVE_MESSAGE)
 743                 dst = IGMP_ALL_ROUTER;
 744         else
 745                 dst = group;
 746
 747         rt = ip_route_output_ports(net, &fl4, NULL, dst, 0,
 748                                    0, 0,
 749                                    IPPROTO_IGMP, 0, dev->ifindex);
 750         if (IS_ERR(rt))
 751                 return -1;
 752
 753         hlen = LL_RESERVED_SPACE(dev);
 754         tlen = dev->needed_tailroom;
 755         skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC);
 756         if (!skb) {
 757                 ip_rt_put(rt);
 758                 return -1;
 759         }
 760         skb->priority = TC_PRIO_CONTROL;
 761
 762         skb_dst_set(skb, &rt->dst);
 763
 764         skb_reserve(skb, hlen);
 765
 766         skb_reset_network_header(skb);
 767         iph = ip_hdr(skb);
 768         skb_put(skb, sizeof(struct iphdr) + 4);
 769
 770         iph->version  = 4;
 771         iph->ihl      = (sizeof(struct iphdr)+4)>>2;
 772         iph->tos      = 0xc0;
 773         iph->frag_off = htons(IP_DF);
 774         iph->ttl      = 1;
 775         iph->daddr    = dst;
 776         iph->saddr    = fl4.saddr;
 777         iph->protocol = IPPROTO_IGMP;
 778         ip_select_ident(net, skb, NULL);
 779         ((u8 *)&iph[1])[0] = IPOPT_RA;
 780         ((u8 *)&iph[1])[1] = 4;
 781         ((u8 *)&iph[1])[2] = 0;
 782         ((u8 *)&iph[1])[3] = 0;
 783
 784         ih = skb_put(skb, sizeof(struct igmphdr));
 785         ih->type = type;
 786         ih->code = 0;
 787         ih->csum = 0;
 788         ih->group = group;
 789         ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 790
 791         return ip_local_out(net, skb->sk, skb);
 792 }
 793
 794 static void igmp_gq_timer_expire(struct timer_list *t)
 795 {
 796         struct in_device *in_dev = from_timer(in_dev, t, mr_gq_timer);
 797
 798         in_dev->mr_gq_running = 0;
 799         igmpv3_send_report(in_dev, NULL);
 800         in_dev_put(in_dev);
 801 }
 802
 803 static void igmp_ifc_timer_expire(struct timer_list *t)
 804 {
 805         struct in_device *in_dev = from_timer(in_dev, t, mr_ifc_timer);
 806
 807         igmpv3_send_cr(in_dev);
 808         if (in_dev->mr_ifc_count) {
 809                 in_dev->mr_ifc_count--;
 810                 igmp_ifc_start_timer(in_dev,
 811                                      unsolicited_report_interval(in_dev));
 812         }
 813         in_dev_put(in_dev);
 814 }
 815
 816 static void igmp_ifc_event(struct in_device *in_dev)
 817 {
 818         struct net *net = dev_net(in_dev->dev);
 819         if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
 820                 return;
 821         in_dev->mr_ifc_count = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
 822         igmp_ifc_start_timer(in_dev, 1);
 823 }
 824
 825
 826 static void igmp_timer_expire(struct timer_list *t)
 827 {
 828         struct ip_mc_list *im = from_timer(im, t, timer);
 829         struct in_device *in_dev = im->interface;
 830
 831         spin_lock(&im->lock);
 832         im->tm_running = 0;
 833
 834         if (im->unsolicit_count && --im->unsolicit_count)
 835                 igmp_start_timer(im, unsolicited_report_interval(in_dev));
 836
 837         im->reporter = 1;
 838         spin_unlock(&im->lock);
 839
 840         if (IGMP_V1_SEEN(in_dev))
 841                 igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
 842         else if (IGMP_V2_SEEN(in_dev))
 843                 igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
 844         else
 845                 igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
 846
 847         ip_ma_put(im);
 848 }
 849
 850 /* mark EXCLUDE-mode sources */
 851 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 852 {
 853         struct ip_sf_list *psf;
 854         int i, scount;
 855
 856         scount = 0;
 857         for (psf = pmc->sources; psf; psf = psf->sf_next) {
 858                 if (scount == nsrcs)
 859                         break;
 860                 for (i = 0; i < nsrcs; i++) {
 861                         /* skip inactive filters */
 862                         if (psf->sf_count[MCAST_INCLUDE] ||
 863                             pmc->sfcount[MCAST_EXCLUDE] !=
 864                             psf->sf_count[MCAST_EXCLUDE])
 865                                 break;
 866                         if (srcs[i] == psf->sf_inaddr) {
 867                                 scount++;
 868                                 break;
 869                         }
 870                 }
 871         }
 872         pmc->gsquery = 0;
 873         if (scount == nsrcs)    /* all sources excluded */
 874                 return 0;
 875         return 1;
 876 }
 877
 878 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
 879 {
 880         struct ip_sf_list *psf;
 881         int i, scount;
 882
 883         if (pmc->sfmode == MCAST_EXCLUDE)
 884                 return igmp_xmarksources(pmc, nsrcs, srcs);
 885
 886         /* mark INCLUDE-mode sources */
 887         scount = 0;
 888         for (psf = pmc->sources; psf; psf = psf->sf_next) {
 889                 if (scount == nsrcs)
 890                         break;
 891                 for (i = 0; i < nsrcs; i++)
 892                         if (srcs[i] == psf->sf_inaddr) {
 893                                 psf->sf_gsresp = 1;
 894                                 scount++;
 895                                 break;
 896                         }
 897         }
 898         if (!scount) {
 899                 pmc->gsquery = 0;
 900                 return 0;
 901         }
 902         pmc->gsquery = 1;
 903         return 1;
 904 }
 905
 906 /* return true if packet was dropped */
 907 static bool igmp_heard_report(struct in_device *in_dev, __be32 group)
 908 {
 909         struct ip_mc_list *im;
 910         struct net *net = dev_net(in_dev->dev);
 911
 912         /* Timers are only set for non-local groups */
 913
 914         if (group == IGMP_ALL_HOSTS)
 915                 return false;
 916         if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
 917                 return false;
 918
 919         rcu_read_lock();
 920         for_each_pmc_rcu(in_dev, im) {
 921                 if (im->multiaddr == group) {
 922                         igmp_stop_timer(im);
 923                         break;
 924                 }
 925         }
 926         rcu_read_unlock();
 927         return false;
 928 }
 929
 930 /* return true if packet was dropped */
 931 static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
 932         int len)
 933 {
 934         struct igmphdr          *ih = igmp_hdr(skb);
 935         struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
 936         struct ip_mc_list       *im;
 937         __be32                  group = ih->group;
 938         int                     max_delay;
 939         int                     mark = 0;
 940         struct net              *net = dev_net(in_dev->dev);
 941
 942
 943         if (len == 8) {
 944                 if (ih->code == 0) {
 945                         /* Alas, old v1 router presents here. */
 946
 947                         max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 948                         in_dev->mr_v1_seen = jiffies +
 949                                 (in_dev->mr_qrv * in_dev->mr_qi) +
 950                                 in_dev->mr_qri;
 951                         group = 0;
 952                 } else {
 953                         /* v2 router present */
 954                         max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
 955                         in_dev->mr_v2_seen = jiffies +
 956                                 (in_dev->mr_qrv * in_dev->mr_qi) +
 957                                 in_dev->mr_qri;
 958                 }
 959                 /* cancel the interface change timer */
 960                 in_dev->mr_ifc_count = 0;
 961                 if (del_timer(&in_dev->mr_ifc_timer))
 962                         __in_dev_put(in_dev);
 963                 /* clear deleted report items */
 964                 igmpv3_clear_delrec(in_dev);
 965         } else if (len < 12) {
 966                 return true;    /* ignore bogus packet; freed by caller */
 967         } else if (IGMP_V1_SEEN(in_dev)) {
 968                 /* This is a v3 query with v1 queriers present */
 969                 max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
 970                 group = 0;
 971         } else if (IGMP_V2_SEEN(in_dev)) {
 972                 /* this is a v3 query with v2 queriers present;
 973                  * Interpretation of the max_delay code is problematic here.
 974                  * A real v2 host would use ih_code directly, while v3 has a
 975                  * different encoding. We use the v3 encoding as more likely
 976                  * to be intended in a v3 query.
 977                  */
 978                 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 979                 if (!max_delay)
 980                         max_delay = 1;  /* can't mod w/ 0 */
 981         } else { /* v3 */
 982                 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
 983                         return true;
 984
 985                 ih3 = igmpv3_query_hdr(skb);
 986                 if (ih3->nsrcs) {
 987                         if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
 988                                            + ntohs(ih3->nsrcs)*sizeof(__be32)))
 989                                 return true;
 990                         ih3 = igmpv3_query_hdr(skb);
 991                 }
 992
 993                 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
 994                 if (!max_delay)
 995                         max_delay = 1;  /* can't mod w/ 0 */
 996                 in_dev->mr_maxdelay = max_delay;
 997
 998                 /* RFC3376, 4.1.6. QRV and 4.1.7. QQIC, when the most recently
 999                  * received value was zero, use the default or statically
1000                  * configured value.
1001                  */
1002                 in_dev->mr_qrv = ih3->qrv ?: net->ipv4.sysctl_igmp_qrv;
1003                 in_dev->mr_qi = IGMPV3_QQIC(ih3->qqic)*HZ ?: IGMP_QUERY_INTERVAL;
1004
1005                 /* RFC3376, 8.3. Query Response Interval:
1006                  * The number of seconds represented by the [Query Response
1007                  * Interval] must be less than the [Query Interval].
1008                  */
1009                 if (in_dev->mr_qri >= in_dev->mr_qi)
1010                         in_dev->mr_qri = (in_dev->mr_qi/HZ - 1)*HZ;
1011
1012                 if (!group) { /* general query */
1013                         if (ih3->nsrcs)
1014                                 return true;    /* no sources allowed */
1015                         igmp_gq_start_timer(in_dev);
1016                         return false;
1017                 }
1018                 /* mark sources to include, if group & source-specific */
1019                 mark = ih3->nsrcs != 0;
1020         }
1021
1022         /*
1023          * - Start the timers in all of our membership records
1024          *   that the query applies to for the interface on
1025          *   which the query arrived excl. those that belong
1026          *   to a "local" group (224.0.0.X)
1027          * - For timers already running check if they need to
1028          *   be reset.
1029          * - Use the igmp->igmp_code field as the maximum
1030          *   delay possible
1031          */
1032         rcu_read_lock();
1033         for_each_pmc_rcu(in_dev, im) {
1034                 int changed;
1035
1036                 if (group && group != im->multiaddr)
1037                         continue;
1038                 if (im->multiaddr == IGMP_ALL_HOSTS)
1039                         continue;
1040                 if (ipv4_is_local_multicast(im->multiaddr) &&
1041                     !net->ipv4.sysctl_igmp_llm_reports)
1042                         continue;
1043                 spin_lock_bh(&im->lock);
1044                 if (im->tm_running)
1045                         im->gsquery = im->gsquery && mark;
1046                 else
1047                         im->gsquery = mark;
1048                 changed = !im->gsquery ||
1049                         igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
1050                 spin_unlock_bh(&im->lock);
1051                 if (changed)
1052                         igmp_mod_timer(im, max_delay);
1053         }
1054         rcu_read_unlock();
1055         return false;
1056 }
1057
1058 /* called in rcu_read_lock() section */
1059 int igmp_rcv(struct sk_buff *skb)
1060 {
1061         /* This basically follows the spec line by line -- see RFC1112 */
1062         struct igmphdr *ih;
1063         struct net_device *dev = skb->dev;
1064         struct in_device *in_dev;
1065         int len = skb->len;
1066         bool dropped = true;
1067
1068         if (netif_is_l3_master(dev)) {
1069                 dev = dev_get_by_index_rcu(dev_net(dev), IPCB(skb)->iif);
1070                 if (!dev)
1071                         goto drop;
1072         }
1073
1074         in_dev = __in_dev_get_rcu(dev);
1075         if (!in_dev)
1076                 goto drop;
1077
1078         if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
1079                 goto drop;
1080
1081         if (skb_checksum_simple_validate(skb))
1082                 goto drop;
1083
1084         ih = igmp_hdr(skb);
1085         switch (ih->type) {
1086         case IGMP_HOST_MEMBERSHIP_QUERY:
1087                 dropped = igmp_heard_query(in_dev, skb, len);
1088                 break;
1089         case IGMP_HOST_MEMBERSHIP_REPORT:
1090         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1091                 /* Is it our report looped back? */
1092                 if (rt_is_output_route(skb_rtable(skb)))
1093                         break;
1094                 /* don't rely on MC router hearing unicast reports */
1095                 if (skb->pkt_type == PACKET_MULTICAST ||
1096                     skb->pkt_type == PACKET_BROADCAST)
1097                         dropped = igmp_heard_report(in_dev, ih->group);
1098                 break;
1099         case IGMP_PIM:
1100 #ifdef CONFIG_IP_PIMSM_V1
1101                 return pim_rcv_v1(skb);
1102 #endif
1103         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1104         case IGMP_DVMRP:
1105         case IGMP_TRACE:
1106         case IGMP_HOST_LEAVE_MESSAGE:
1107         case IGMP_MTRACE:
1108         case IGMP_MTRACE_RESP:
1109                 break;
1110         default:
1111                 break;
1112         }
1113
1114 drop:
1115         if (dropped)
1116                 kfree_skb(skb);
1117         else
1118                 consume_skb(skb);
1119         return 0;
1120 }
1121
1122 #endif
1123
1124
1125 /*
1126  *      Add a filter to a device
1127  */
1128
1129 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1130 {
1131         char buf[MAX_ADDR_LEN];
1132         struct net_device *dev = in_dev->dev;
1133
1134         /* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1135            We will get multicast token leakage, when IFF_MULTICAST
1136            is changed. This check should be done in ndo_set_rx_mode
1137            routine. Something sort of:
1138            if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1139            --ANK
1140            */
1141         if (arp_mc_map(addr, buf, dev, 0) == 0)
1142                 dev_mc_add(dev, buf);
1143 }
1144
1145 /*
1146  *      Remove a filter from a device
1147  */
1148
1149 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1150 {
1151         char buf[MAX_ADDR_LEN];
1152         struct net_device *dev = in_dev->dev;
1153
1154         if (arp_mc_map(addr, buf, dev, 0) == 0)
1155                 dev_mc_del(dev, buf);
1156 }
1157
1158 #ifdef CONFIG_IP_MULTICAST
1159 /*
1160  * deleted ip_mc_list manipulation
1161  */
1162 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im,
1163                               gfp_t gfp)
1164 {
1165         struct ip_mc_list *pmc;
1166         struct net *net = dev_net(in_dev->dev);
1167
1168         /* this is an "ip_mc_list" for convenience; only the fields below
1169          * are actually used. In particular, the refcnt and users are not
1170          * used for management of the delete list. Using the same structure
1171          * for deleted items allows change reports to use common code with
1172          * non-deleted or query-response MCA's.
1173          */
1174         pmc = kzalloc(sizeof(*pmc), gfp);
1175         if (!pmc)
1176                 return;
1177         spin_lock_init(&pmc->lock);
1178         spin_lock_bh(&im->lock);
1179         pmc->interface = im->interface;
1180         in_dev_hold(in_dev);
1181         pmc->multiaddr = im->multiaddr;
1182         pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1183         pmc->sfmode = im->sfmode;
1184         if (pmc->sfmode == MCAST_INCLUDE) {
1185                 struct ip_sf_list *psf;
1186
1187                 pmc->tomb = im->tomb;
1188                 pmc->sources = im->sources;
1189                 im->tomb = im->sources = NULL;
1190                 for (psf = pmc->sources; psf; psf = psf->sf_next)
1191                         psf->sf_crcount = pmc->crcount;
1192         }
1193         spin_unlock_bh(&im->lock);
1194
1195         spin_lock_bh(&in_dev->mc_tomb_lock);
1196         pmc->next = in_dev->mc_tomb;
1197         in_dev->mc_tomb = pmc;
1198         spin_unlock_bh(&in_dev->mc_tomb_lock);
1199 }
1200
1201 /*
1202  * restore ip_mc_list deleted records
1203  */
1204 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1205 {
1206         struct ip_mc_list *pmc, *pmc_prev;
1207         struct ip_sf_list *psf;
1208         struct net *net = dev_net(in_dev->dev);
1209         __be32 multiaddr = im->multiaddr;
1210
1211         spin_lock_bh(&in_dev->mc_tomb_lock);
1212         pmc_prev = NULL;
1213         for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) {
1214                 if (pmc->multiaddr == multiaddr)
1215                         break;
1216                 pmc_prev = pmc;
1217         }
1218         if (pmc) {
1219                 if (pmc_prev)
1220                         pmc_prev->next = pmc->next;
1221                 else
1222                         in_dev->mc_tomb = pmc->next;
1223         }
1224         spin_unlock_bh(&in_dev->mc_tomb_lock);
1225
1226         spin_lock_bh(&im->lock);
1227         if (pmc) {
1228                 im->interface = pmc->interface;
1229                 if (im->sfmode == MCAST_INCLUDE) {
1230                         swap(im->tomb, pmc->tomb);
1231                         swap(im->sources, pmc->sources);
1232                         for (psf = im->sources; psf; psf = psf->sf_next)
1233                                 psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1234                 } else {
1235                         im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1236                 }
1237                 in_dev_put(pmc->interface);
1238                 kfree_pmc(pmc);
1239         }
1240         spin_unlock_bh(&im->lock);
1241 }
1242
1243 /*
1244  * flush ip_mc_list deleted records
1245  */
1246 static void igmpv3_clear_delrec(struct in_device *in_dev)
1247 {
1248         struct ip_mc_list *pmc, *nextpmc;
1249
1250         spin_lock_bh(&in_dev->mc_tomb_lock);
1251         pmc = in_dev->mc_tomb;
1252         in_dev->mc_tomb = NULL;
1253         spin_unlock_bh(&in_dev->mc_tomb_lock);
1254
1255         for (; pmc; pmc = nextpmc) {
1256                 nextpmc = pmc->next;
1257                 ip_mc_clear_src(pmc);
1258                 in_dev_put(pmc->interface);
1259                 kfree_pmc(pmc);
1260         }
1261         /* clear dead sources, too */
1262         rcu_read_lock();
1263         for_each_pmc_rcu(in_dev, pmc) {
1264                 struct ip_sf_list *psf;
1265
1266                 spin_lock_bh(&pmc->lock);
1267                 psf = pmc->tomb;
1268                 pmc->tomb = NULL;
1269                 spin_unlock_bh(&pmc->lock);
1270                 ip_sf_list_clear_all(psf);
1271         }
1272         rcu_read_unlock();
1273 }
1274 #endif
1275
1276 static void __igmp_group_dropped(struct ip_mc_list *im, gfp_t gfp)
1277 {
1278         struct in_device *in_dev = im->interface;
1279 #ifdef CONFIG_IP_MULTICAST
1280         struct net *net = dev_net(in_dev->dev);
1281         int reporter;
1282 #endif
1283
1284         if (im->loaded) {
1285                 im->loaded = 0;
1286                 ip_mc_filter_del(in_dev, im->multiaddr);
1287         }
1288
1289 #ifdef CONFIG_IP_MULTICAST
1290         if (im->multiaddr == IGMP_ALL_HOSTS)
1291                 return;
1292         if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1293                 return;
1294
1295         reporter = im->reporter;
1296         igmp_stop_timer(im);
1297
1298         if (!in_dev->dead) {
1299                 if (IGMP_V1_SEEN(in_dev))
1300                         return;
1301                 if (IGMP_V2_SEEN(in_dev)) {
1302                         if (reporter)
1303                                 igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1304                         return;
1305                 }
1306                 /* IGMPv3 */
1307                 igmpv3_add_delrec(in_dev, im, gfp);
1308
1309                 igmp_ifc_event(in_dev);
1310         }
1311 #endif
1312 }
1313
1314 static void igmp_group_dropped(struct ip_mc_list *im)
1315 {
1316         __igmp_group_dropped(im, GFP_KERNEL);
1317 }
1318
1319 static void igmp_group_added(struct ip_mc_list *im)
1320 {
1321         struct in_device *in_dev = im->interface;
1322 #ifdef CONFIG_IP_MULTICAST
1323         struct net *net = dev_net(in_dev->dev);
1324 #endif
1325
1326         if (im->loaded == 0) {
1327                 im->loaded = 1;
1328                 ip_mc_filter_add(in_dev, im->multiaddr);
1329         }
1330
1331 #ifdef CONFIG_IP_MULTICAST
1332         if (im->multiaddr == IGMP_ALL_HOSTS)
1333                 return;
1334         if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1335                 return;
1336
1337         if (in_dev->dead)
1338                 return;
1339
1340         im->unsolicit_count = net->ipv4.sysctl_igmp_qrv;
1341         if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1342                 spin_lock_bh(&im->lock);
1343                 igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY);
1344                 spin_unlock_bh(&im->lock);
1345                 return;
1346         }
1347         /* else, v3 */
1348
1349         /* Based on RFC3376 5.1, for newly added INCLUDE SSM, we should
1350          * not send filter-mode change record as the mode should be from
1351          * IN() to IN(A).
1352          */
1353         if (im->sfmode == MCAST_EXCLUDE)
1354                 im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1355
1356         igmp_ifc_event(in_dev);
1357 #endif
1358 }
1359
1360
1361 /*
1362  *      Multicast list managers
1363  */
1364
1365 static u32 ip_mc_hash(const struct ip_mc_list *im)
1366 {
1367         return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
1368 }
1369
1370 static void ip_mc_hash_add(struct in_device *in_dev,
1371                            struct ip_mc_list *im)
1372 {
1373         struct ip_mc_list __rcu **mc_hash;
1374         u32 hash;
1375
1376         mc_hash = rtnl_dereference(in_dev->mc_hash);
1377         if (mc_hash) {
1378                 hash = ip_mc_hash(im);
1379                 im->next_hash = mc_hash[hash];
1380                 rcu_assign_pointer(mc_hash[hash], im);
1381                 return;
1382         }
1383
1384         /* do not use a hash table for small number of items */
1385         if (in_dev->mc_count < 4)
1386                 return;
1387
1388         mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
1389                           GFP_KERNEL);
1390         if (!mc_hash)
1391                 return;
1392
1393         for_each_pmc_rtnl(in_dev, im) {
1394                 hash = ip_mc_hash(im);
1395                 im->next_hash = mc_hash[hash];
1396                 RCU_INIT_POINTER(mc_hash[hash], im);
1397         }
1398
1399         rcu_assign_pointer(in_dev->mc_hash, mc_hash);
1400 }
1401
1402 static void ip_mc_hash_remove(struct in_device *in_dev,
1403                               struct ip_mc_list *im)
1404 {
1405         struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
1406         struct ip_mc_list *aux;
1407
1408         if (!mc_hash)
1409                 return;
1410         mc_hash += ip_mc_hash(im);
1411         while ((aux = rtnl_dereference(*mc_hash)) != im)
1412                 mc_hash = &aux->next_hash;
1413         *mc_hash = im->next_hash;
1414 }
1415
1416
1417 /*
1418  *      A socket has joined a multicast group on device dev.
1419  */
1420 static void ____ip_mc_inc_group(struct in_device *in_dev, __be32 addr,
1421                                 unsigned int mode, gfp_t gfp)
1422 {
1423         struct ip_mc_list *im;
1424
1425         ASSERT_RTNL();
1426
1427         for_each_pmc_rtnl(in_dev, im) {
1428                 if (im->multiaddr == addr) {
1429                         im->users++;
1430                         ip_mc_add_src(in_dev, &addr, mode, 0, NULL, 0);
1431                         goto out;
1432                 }
1433         }
1434
1435         im = kzalloc(sizeof(*im), gfp);
1436         if (!im)
1437                 goto out;
1438
1439         im->users = 1;
1440         im->interface = in_dev;
1441         in_dev_hold(in_dev);
1442         im->multiaddr = addr;
1443         /* initial mode is (EX, empty) */
1444         im->sfmode = mode;
1445         im->sfcount[mode] = 1;
1446         refcount_set(&im->refcnt, 1);
1447         spin_lock_init(&im->lock);
1448 #ifdef CONFIG_IP_MULTICAST
1449         timer_setup(&im->timer, igmp_timer_expire, 0);
1450 #endif
1451
1452         im->next_rcu = in_dev->mc_list;
1453         in_dev->mc_count++;
1454         rcu_assign_pointer(in_dev->mc_list, im);
1455
1456         ip_mc_hash_add(in_dev, im);
1457
1458 #ifdef CONFIG_IP_MULTICAST
1459         igmpv3_del_delrec(in_dev, im);
1460 #endif
1461         igmp_group_added(im);
1462         if (!in_dev->dead)
1463                 ip_rt_multicast_event(in_dev);
1464 out:
1465         return;
1466 }
1467
1468 void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr, gfp_t gfp)
1469 {
1470         ____ip_mc_inc_group(in_dev, addr, MCAST_EXCLUDE, gfp);
1471 }
1472 EXPORT_SYMBOL(__ip_mc_inc_group);
1473
1474 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1475 {
1476         __ip_mc_inc_group(in_dev, addr, GFP_KERNEL);
1477 }
1478 EXPORT_SYMBOL(ip_mc_inc_group);
1479
1480 static int ip_mc_check_iphdr(struct sk_buff *skb)
1481 {
1482         const struct iphdr *iph;
1483         unsigned int len;
1484         unsigned int offset = skb_network_offset(skb) + sizeof(*iph);
1485
1486         if (!pskb_may_pull(skb, offset))
1487                 return -EINVAL;
1488
1489         iph = ip_hdr(skb);
1490
1491         if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph))
1492                 return -EINVAL;
1493
1494         offset += ip_hdrlen(skb) - sizeof(*iph);
1495
1496         if (!pskb_may_pull(skb, offset))
1497                 return -EINVAL;
1498
1499         iph = ip_hdr(skb);
1500
1501         if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1502                 return -EINVAL;
1503
1504         len = skb_network_offset(skb) + ntohs(iph->tot_len);
1505         if (skb->len < len || len < offset)
1506                 return -EINVAL;
1507
1508         skb_set_transport_header(skb, offset);
1509
1510         return 0;
1511 }
1512
1513 static int ip_mc_check_igmp_reportv3(struct sk_buff *skb)
1514 {
1515         unsigned int len = skb_transport_offset(skb);
1516
1517         len += sizeof(struct igmpv3_report);
1518
1519         return ip_mc_may_pull(skb, len) ? 0 : -EINVAL;
1520 }
1521
1522 static int ip_mc_check_igmp_query(struct sk_buff *skb)
1523 {
1524         unsigned int transport_len = ip_transport_len(skb);
1525         unsigned int len;
1526
1527         /* IGMPv{1,2}? */
1528         if (transport_len != sizeof(struct igmphdr)) {
1529                 /* or IGMPv3? */
1530                 if (transport_len < sizeof(struct igmpv3_query))
1531                         return -EINVAL;
1532
1533                 len = skb_transport_offset(skb) + sizeof(struct igmpv3_query);
1534                 if (!ip_mc_may_pull(skb, len))
1535                         return -EINVAL;
1536         }
1537
1538         /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1539          * all-systems destination addresses (224.0.0.1) for general queries
1540          */
1541         if (!igmp_hdr(skb)->group &&
1542             ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP))
1543                 return -EINVAL;
1544
1545         return 0;
1546 }
1547
1548 static int ip_mc_check_igmp_msg(struct sk_buff *skb)
1549 {
1550         switch (igmp_hdr(skb)->type) {
1551         case IGMP_HOST_LEAVE_MESSAGE:
1552         case IGMP_HOST_MEMBERSHIP_REPORT:
1553         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1554                 return 0;
1555         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1556                 return ip_mc_check_igmp_reportv3(skb);
1557         case IGMP_HOST_MEMBERSHIP_QUERY:
1558                 return ip_mc_check_igmp_query(skb);
1559         default:
1560                 return -ENOMSG;
1561         }
1562 }
1563
1564 static __sum16 ip_mc_validate_checksum(struct sk_buff *skb)
1565 {
1566         return skb_checksum_simple_validate(skb);
1567 }
1568
1569 static int ip_mc_check_igmp_csum(struct sk_buff *skb)
1570 {
1571         unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr);
1572         unsigned int transport_len = ip_transport_len(skb);
1573         struct sk_buff *skb_chk;
1574
1575         if (!ip_mc_may_pull(skb, len))
1576                 return -EINVAL;
1577
1578         skb_chk = skb_checksum_trimmed(skb, transport_len,
1579                                        ip_mc_validate_checksum);
1580         if (!skb_chk)
1581                 return -EINVAL;
1582
1583         if (skb_chk != skb)
1584                 kfree_skb(skb_chk);
1585
1586         return 0;
1587 }
1588
1589 /**
1590  * ip_mc_check_igmp - checks whether this is a sane IGMP packet
1591  * @skb: the skb to validate
1592  *
1593  * Checks whether an IPv4 packet is a valid IGMP packet. If so sets
1594  * skb transport header accordingly and returns zero.
1595  *
1596  * -EINVAL: A broken packet was detected, i.e. it violates some internet
1597  *  standard
1598  * -ENOMSG: IP header validation succeeded but it is not an IGMP packet.
1599  * -ENOMEM: A memory allocation failure happened.
1600  *
1601  * Caller needs to set the skb network header and free any returned skb if it
1602  * differs from the provided skb.
1603  */
1604 int ip_mc_check_igmp(struct sk_buff *skb)
1605 {
1606         int ret = ip_mc_check_iphdr(skb);
1607
1608         if (ret < 0)
1609                 return ret;
1610
1611         if (ip_hdr(skb)->protocol != IPPROTO_IGMP)
1612                 return -ENOMSG;
1613
1614         ret = ip_mc_check_igmp_csum(skb);
1615         if (ret < 0)
1616                 return ret;
1617
1618         return ip_mc_check_igmp_msg(skb);
1619 }
1620 EXPORT_SYMBOL(ip_mc_check_igmp);
1621
1622 /*
1623  *      Resend IGMP JOIN report; used by netdev notifier.
1624  */
1625 static void ip_mc_rejoin_groups(struct in_device *in_dev)
1626 {
1627 #ifdef CONFIG_IP_MULTICAST
1628         struct ip_mc_list *im;
1629         int type;
1630         struct net *net = dev_net(in_dev->dev);
1631
1632         ASSERT_RTNL();
1633
1634         for_each_pmc_rtnl(in_dev, im) {
1635                 if (im->multiaddr == IGMP_ALL_HOSTS)
1636                         continue;
1637                 if (ipv4_is_local_multicast(im->multiaddr) &&
1638                     !net->ipv4.sysctl_igmp_llm_reports)
1639                         continue;
1640
1641                 /* a failover is happening and switches
1642                  * must be notified immediately
1643                  */
1644                 if (IGMP_V1_SEEN(in_dev))
1645                         type = IGMP_HOST_MEMBERSHIP_REPORT;
1646                 else if (IGMP_V2_SEEN(in_dev))
1647                         type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1648                 else
1649                         type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1650                 igmp_send_report(in_dev, im, type);
1651         }
1652 #endif
1653 }
1654
1655 /*
1656  *      A socket has left a multicast group on device dev
1657  */
1658
1659 void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp)
1660 {
1661         struct ip_mc_list *i;
1662         struct ip_mc_list __rcu **ip;
1663
1664         ASSERT_RTNL();
1665
1666         for (ip = &in_dev->mc_list;
1667              (i = rtnl_dereference(*ip)) != NULL;
1668              ip = &i->next_rcu) {
1669                 if (i->multiaddr == addr) {
1670                         if (--i->users == 0) {
1671                                 ip_mc_hash_remove(in_dev, i);
1672                                 *ip = i->next_rcu;
1673                                 in_dev->mc_count--;
1674                                 __igmp_group_dropped(i, gfp);
1675                                 ip_mc_clear_src(i);
1676
1677                                 if (!in_dev->dead)
1678                                         ip_rt_multicast_event(in_dev);
1679
1680                                 ip_ma_put(i);
1681                                 return;
1682                         }
1683                         break;
1684                 }
1685         }
1686 }
1687 EXPORT_SYMBOL(__ip_mc_dec_group);
1688
1689 /* Device changing type */
1690
1691 void ip_mc_unmap(struct in_device *in_dev)
1692 {
1693         struct ip_mc_list *pmc;
1694
1695         ASSERT_RTNL();
1696
1697         for_each_pmc_rtnl(in_dev, pmc)
1698                 igmp_group_dropped(pmc);
1699 }
1700
1701 void ip_mc_remap(struct in_device *in_dev)
1702 {
1703         struct ip_mc_list *pmc;
1704
1705         ASSERT_RTNL();
1706
1707         for_each_pmc_rtnl(in_dev, pmc) {
1708 #ifdef CONFIG_IP_MULTICAST
1709                 igmpv3_del_delrec(in_dev, pmc);
1710 #endif
1711                 igmp_group_added(pmc);
1712         }
1713 }
1714
1715 /* Device going down */
1716
1717 void ip_mc_down(struct in_device *in_dev)
1718 {
1719         struct ip_mc_list *pmc;
1720
1721         ASSERT_RTNL();
1722
1723         for_each_pmc_rtnl(in_dev, pmc)
1724                 igmp_group_dropped(pmc);
1725
1726 #ifdef CONFIG_IP_MULTICAST
1727         in_dev->mr_ifc_count = 0;
1728         if (del_timer(&in_dev->mr_ifc_timer))
1729                 __in_dev_put(in_dev);
1730         in_dev->mr_gq_running = 0;
1731         if (del_timer(&in_dev->mr_gq_timer))
1732                 __in_dev_put(in_dev);
1733 #endif
1734
1735         ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1736 }
1737
1738 #ifdef CONFIG_IP_MULTICAST
1739 static void ip_mc_reset(struct in_device *in_dev)
1740 {
1741         struct net *net = dev_net(in_dev->dev);
1742
1743         in_dev->mr_qi = IGMP_QUERY_INTERVAL;
1744         in_dev->mr_qri = IGMP_QUERY_RESPONSE_INTERVAL;
1745         in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1746 }
1747 #else
1748 static void ip_mc_reset(struct in_device *in_dev)
1749 {
1750 }
1751 #endif
1752
1753 void ip_mc_init_dev(struct in_device *in_dev)
1754 {
1755         ASSERT_RTNL();
1756
1757 #ifdef CONFIG_IP_MULTICAST
1758         timer_setup(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 0);
1759         timer_setup(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 0);
1760 #endif
1761         ip_mc_reset(in_dev);
1762
1763         spin_lock_init(&in_dev->mc_tomb_lock);
1764 }
1765
1766 /* Device going up */
1767
1768 void ip_mc_up(struct in_device *in_dev)
1769 {
1770         struct ip_mc_list *pmc;
1771
1772         ASSERT_RTNL();
1773
1774         ip_mc_reset(in_dev);
1775         ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1776
1777         for_each_pmc_rtnl(in_dev, pmc) {
1778 #ifdef CONFIG_IP_MULTICAST
1779                 igmpv3_del_delrec(in_dev, pmc);
1780 #endif
1781                 igmp_group_added(pmc);
1782         }
1783 }
1784
1785 /*
1786  *      Device is about to be destroyed: clean up.
1787  */
1788
1789 void ip_mc_destroy_dev(struct in_device *in_dev)
1790 {
1791         struct ip_mc_list *i;
1792
1793         ASSERT_RTNL();
1794
1795         /* Deactivate timers */
1796         ip_mc_down(in_dev);
1797 #ifdef CONFIG_IP_MULTICAST
1798         igmpv3_clear_delrec(in_dev);
1799 #endif
1800
1801         while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1802                 in_dev->mc_list = i->next_rcu;
1803                 in_dev->mc_count--;
1804                 ip_ma_put(i);
1805         }
1806 }
1807
1808 /* RTNL is locked */
1809 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1810 {
1811         struct net_device *dev = NULL;
1812         struct in_device *idev = NULL;
1813
1814         if (imr->imr_ifindex) {
1815                 idev = inetdev_by_index(net, imr->imr_ifindex);
1816                 return idev;
1817         }
1818         if (imr->imr_address.s_addr) {
1819                 dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1820                 if (!dev)
1821                         return NULL;
1822         }
1823
1824         if (!dev) {
1825                 struct rtable *rt = ip_route_output(net,
1826                                                     imr->imr_multiaddr.s_addr,
1827                                                     0, 0, 0);
1828                 if (!IS_ERR(rt)) {
1829                         dev = rt->dst.dev;
1830                         ip_rt_put(rt);
1831                 }
1832         }
1833         if (dev) {
1834                 imr->imr_ifindex = dev->ifindex;
1835                 idev = __in_dev_get_rtnl(dev);
1836         }
1837         return idev;
1838 }
1839
1840 /*
1841  *      Join a socket to a group
1842  */
1843
1844 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1845         __be32 *psfsrc)
1846 {
1847         struct ip_sf_list *psf, *psf_prev;
1848         int rv = 0;
1849
1850         psf_prev = NULL;
1851         for (psf = pmc->sources; psf; psf = psf->sf_next) {
1852                 if (psf->sf_inaddr == *psfsrc)
1853                         break;
1854                 psf_prev = psf;
1855         }
1856         if (!psf || psf->sf_count[sfmode] == 0) {
1857                 /* source filter not found, or count wrong =>  bug */
1858                 return -ESRCH;
1859         }
1860         psf->sf_count[sfmode]--;
1861         if (psf->sf_count[sfmode] == 0) {
1862                 ip_rt_multicast_event(pmc->interface);
1863         }
1864         if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1865 #ifdef CONFIG_IP_MULTICAST
1866                 struct in_device *in_dev = pmc->interface;
1867                 struct net *net = dev_net(in_dev->dev);
1868 #endif
1869
1870                 /* no more filters for this source */
1871                 if (psf_prev)
1872                         psf_prev->sf_next = psf->sf_next;
1873                 else
1874                         pmc->sources = psf->sf_next;
1875 #ifdef CONFIG_IP_MULTICAST
1876                 if (psf->sf_oldin &&
1877                     !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1878                         psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1879                         psf->sf_next = pmc->tomb;
1880                         pmc->tomb = psf;
1881                         rv = 1;
1882                 } else
1883 #endif
1884                         kfree(psf);
1885         }
1886         return rv;
1887 }
1888
1889 #ifndef CONFIG_IP_MULTICAST
1890 #define igmp_ifc_event(x)       do { } while (0)
1891 #endif
1892
1893 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1894                          int sfcount, __be32 *psfsrc, int delta)
1895 {
1896         struct ip_mc_list *pmc;
1897         int     changerec = 0;
1898         int     i, err;
1899
1900         if (!in_dev)
1901                 return -ENODEV;
1902         rcu_read_lock();
1903         for_each_pmc_rcu(in_dev, pmc) {
1904                 if (*pmca == pmc->multiaddr)
1905                         break;
1906         }
1907         if (!pmc) {
1908                 /* MCA not found?? bug */
1909                 rcu_read_unlock();
1910                 return -ESRCH;
1911         }
1912         spin_lock_bh(&pmc->lock);
1913         rcu_read_unlock();
1914 #ifdef CONFIG_IP_MULTICAST
1915         sf_markstate(pmc);
1916 #endif
1917         if (!delta) {
1918                 err = -EINVAL;
1919                 if (!pmc->sfcount[sfmode])
1920                         goto out_unlock;
1921                 pmc->sfcount[sfmode]--;
1922         }
1923         err = 0;
1924         for (i = 0; i < sfcount; i++) {
1925                 int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1926
1927                 changerec |= rv > 0;
1928                 if (!err && rv < 0)
1929                         err = rv;
1930         }
1931         if (pmc->sfmode == MCAST_EXCLUDE &&
1932             pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1933             pmc->sfcount[MCAST_INCLUDE]) {
1934 #ifdef CONFIG_IP_MULTICAST
1935                 struct ip_sf_list *psf;
1936                 struct net *net = dev_net(in_dev->dev);
1937 #endif
1938
1939                 /* filter mode change */
1940                 pmc->sfmode = MCAST_INCLUDE;
1941 #ifdef CONFIG_IP_MULTICAST
1942                 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1943                 in_dev->mr_ifc_count = pmc->crcount;
1944                 for (psf = pmc->sources; psf; psf = psf->sf_next)
1945                         psf->sf_crcount = 0;
1946                 igmp_ifc_event(pmc->interface);
1947         } else if (sf_setstate(pmc) || changerec) {
1948                 igmp_ifc_event(pmc->interface);
1949 #endif
1950         }
1951 out_unlock:
1952         spin_unlock_bh(&pmc->lock);
1953         return err;
1954 }
1955
1956 /*
1957  * Add multicast single-source filter to the interface list
1958  */
1959 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1960         __be32 *psfsrc)
1961 {
1962         struct ip_sf_list *psf, *psf_prev;
1963
1964         psf_prev = NULL;
1965         for (psf = pmc->sources; psf; psf = psf->sf_next) {
1966                 if (psf->sf_inaddr == *psfsrc)
1967                         break;
1968                 psf_prev = psf;
1969         }
1970         if (!psf) {
1971                 psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1972                 if (!psf)
1973                         return -ENOBUFS;
1974                 psf->sf_inaddr = *psfsrc;
1975                 if (psf_prev) {
1976                         psf_prev->sf_next = psf;
1977                 } else
1978                         pmc->sources = psf;
1979         }
1980         psf->sf_count[sfmode]++;
1981         if (psf->sf_count[sfmode] == 1) {
1982                 ip_rt_multicast_event(pmc->interface);
1983         }
1984         return 0;
1985 }
1986
1987 #ifdef CONFIG_IP_MULTICAST
1988 static void sf_markstate(struct ip_mc_list *pmc)
1989 {
1990         struct ip_sf_list *psf;
1991         int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
1992
1993         for (psf = pmc->sources; psf; psf = psf->sf_next)
1994                 if (pmc->sfcount[MCAST_EXCLUDE]) {
1995                         psf->sf_oldin = mca_xcount ==
1996                                 psf->sf_count[MCAST_EXCLUDE] &&
1997                                 !psf->sf_count[MCAST_INCLUDE];
1998                 } else
1999                         psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2000 }
2001
2002 static int sf_setstate(struct ip_mc_list *pmc)
2003 {
2004         struct ip_sf_list *psf, *dpsf;
2005         int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
2006         int qrv = pmc->interface->mr_qrv;
2007         int new_in, rv;
2008
2009         rv = 0;
2010         for (psf = pmc->sources; psf; psf = psf->sf_next) {
2011                 if (pmc->sfcount[MCAST_EXCLUDE]) {
2012                         new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2013                                 !psf->sf_count[MCAST_INCLUDE];
2014                 } else
2015                         new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2016                 if (new_in) {
2017                         if (!psf->sf_oldin) {
2018                                 struct ip_sf_list *prev = NULL;
2019
2020                                 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) {
2021                                         if (dpsf->sf_inaddr == psf->sf_inaddr)
2022                                                 break;
2023                                         prev = dpsf;
2024                                 }
2025                                 if (dpsf) {
2026                                         if (prev)
2027                                                 prev->sf_next = dpsf->sf_next;
2028                                         else
2029                                                 pmc->tomb = dpsf->sf_next;
2030                                         kfree(dpsf);
2031                                 }
2032                                 psf->sf_crcount = qrv;
2033                                 rv++;
2034                         }
2035                 } else if (psf->sf_oldin) {
2036
2037                         psf->sf_crcount = 0;
2038                         /*
2039                          * add or update "delete" records if an active filter
2040                          * is now inactive
2041                          */
2042                         for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next)
2043                                 if (dpsf->sf_inaddr == psf->sf_inaddr)
2044                                         break;
2045                         if (!dpsf) {
2046                                 dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
2047                                 if (!dpsf)
2048                                         continue;
2049                                 *dpsf = *psf;
2050                                 /* pmc->lock held by callers */
2051                                 dpsf->sf_next = pmc->tomb;
2052                                 pmc->tomb = dpsf;
2053                         }
2054                         dpsf->sf_crcount = qrv;
2055                         rv++;
2056                 }
2057         }
2058         return rv;
2059 }
2060 #endif
2061
2062 /*
2063  * Add multicast source filter list to the interface list
2064  */
2065 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
2066                          int sfcount, __be32 *psfsrc, int delta)
2067 {
2068         struct ip_mc_list *pmc;
2069         int     isexclude;
2070         int     i, err;
2071
2072         if (!in_dev)
2073                 return -ENODEV;
2074         rcu_read_lock();
2075         for_each_pmc_rcu(in_dev, pmc) {
2076                 if (*pmca == pmc->multiaddr)
2077                         break;
2078         }
2079         if (!pmc) {
2080                 /* MCA not found?? bug */
2081                 rcu_read_unlock();
2082                 return -ESRCH;
2083         }
2084         spin_lock_bh(&pmc->lock);
2085         rcu_read_unlock();
2086
2087 #ifdef CONFIG_IP_MULTICAST
2088         sf_markstate(pmc);
2089 #endif
2090         isexclude = pmc->sfmode == MCAST_EXCLUDE;
2091         if (!delta)
2092                 pmc->sfcount[sfmode]++;
2093         err = 0;
2094         for (i = 0; i < sfcount; i++) {
2095                 err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2096                 if (err)
2097                         break;
2098         }
2099         if (err) {
2100                 int j;
2101
2102                 if (!delta)
2103                         pmc->sfcount[sfmode]--;
2104                 for (j = 0; j < i; j++)
2105                         (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2106         } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
2107 #ifdef CONFIG_IP_MULTICAST
2108                 struct ip_sf_list *psf;
2109                 struct net *net = dev_net(pmc->interface->dev);
2110                 in_dev = pmc->interface;
2111 #endif
2112
2113                 /* filter mode change */
2114                 if (pmc->sfcount[MCAST_EXCLUDE])
2115                         pmc->sfmode = MCAST_EXCLUDE;
2116                 else if (pmc->sfcount[MCAST_INCLUDE])
2117                         pmc->sfmode = MCAST_INCLUDE;
2118 #ifdef CONFIG_IP_MULTICAST
2119                 /* else no filters; keep old mode for reports */
2120
2121                 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
2122                 in_dev->mr_ifc_count = pmc->crcount;
2123                 for (psf = pmc->sources; psf; psf = psf->sf_next)
2124                         psf->sf_crcount = 0;
2125                 igmp_ifc_event(in_dev);
2126         } else if (sf_setstate(pmc)) {
2127                 igmp_ifc_event(in_dev);
2128 #endif
2129         }
2130         spin_unlock_bh(&pmc->lock);
2131         return err;
2132 }
2133
2134 static void ip_mc_clear_src(struct ip_mc_list *pmc)
2135 {
2136         struct ip_sf_list *tomb, *sources;
2137
2138         spin_lock_bh(&pmc->lock);
2139         tomb = pmc->tomb;
2140         pmc->tomb = NULL;
2141         sources = pmc->sources;
2142         pmc->sources = NULL;
2143         pmc->sfmode = MCAST_EXCLUDE;
2144         pmc->sfcount[MCAST_INCLUDE] = 0;
2145         pmc->sfcount[MCAST_EXCLUDE] = 1;
2146         spin_unlock_bh(&pmc->lock);
2147
2148         ip_sf_list_clear_all(tomb);
2149         ip_sf_list_clear_all(sources);
2150 }
2151
2152 /* Join a multicast group
2153  */
2154 static int __ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr,
2155                               unsigned int mode)
2156 {
2157         __be32 addr = imr->imr_multiaddr.s_addr;
2158         struct ip_mc_socklist *iml, *i;
2159         struct in_device *in_dev;
2160         struct inet_sock *inet = inet_sk(sk);
2161         struct net *net = sock_net(sk);
2162         int ifindex;
2163         int count = 0;
2164         int err;
2165
2166         ASSERT_RTNL();
2167
2168         if (!ipv4_is_multicast(addr))
2169                 return -EINVAL;
2170
2171         in_dev = ip_mc_find_dev(net, imr);
2172
2173         if (!in_dev) {
2174                 err = -ENODEV;
2175                 goto done;
2176         }
2177
2178         err = -EADDRINUSE;
2179         ifindex = imr->imr_ifindex;
2180         for_each_pmc_rtnl(inet, i) {
2181                 if (i->multi.imr_multiaddr.s_addr == addr &&
2182                     i->multi.imr_ifindex == ifindex)
2183                         goto done;
2184                 count++;
2185         }
2186         err = -ENOBUFS;
2187         if (count >= net->ipv4.sysctl_igmp_max_memberships)
2188                 goto done;
2189         iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
2190         if (!iml)
2191                 goto done;
2192
2193         memcpy(&iml->multi, imr, sizeof(*imr));
2194         iml->next_rcu = inet->mc_list;
2195         iml->sflist = NULL;
2196         iml->sfmode = mode;
2197         rcu_assign_pointer(inet->mc_list, iml);
2198         ____ip_mc_inc_group(in_dev, addr, mode, GFP_KERNEL);
2199         err = 0;
2200 done:
2201         return err;
2202 }
2203
2204 /* Join ASM (Any-Source Multicast) group
2205  */
2206 int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
2207 {
2208         return __ip_mc_join_group(sk, imr, MCAST_EXCLUDE);
2209 }
2210 EXPORT_SYMBOL(ip_mc_join_group);
2211
2212 /* Join SSM (Source-Specific Multicast) group
2213  */
2214 int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr,
2215                          unsigned int mode)
2216 {
2217         return __ip_mc_join_group(sk, imr, mode);
2218 }
2219
2220 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
2221                            struct in_device *in_dev)
2222 {
2223         struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
2224         int err;
2225
2226         if (!psf) {
2227                 /* any-source empty exclude case */
2228                 return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2229                         iml->sfmode, 0, NULL, 0);
2230         }
2231         err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2232                         iml->sfmode, psf->sl_count, psf->sl_addr, 0);
2233         RCU_INIT_POINTER(iml->sflist, NULL);
2234         /* decrease mem now to avoid the memleak warning */
2235         atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc);
2236         kfree_rcu(psf, rcu);
2237         return err;
2238 }
2239
2240 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
2241 {
2242         struct inet_sock *inet = inet_sk(sk);
2243         struct ip_mc_socklist *iml;
2244         struct ip_mc_socklist __rcu **imlp;
2245         struct in_device *in_dev;
2246         struct net *net = sock_net(sk);
2247         __be32 group = imr->imr_multiaddr.s_addr;
2248         u32 ifindex;
2249         int ret = -EADDRNOTAVAIL;
2250
2251         ASSERT_RTNL();
2252
2253         in_dev = ip_mc_find_dev(net, imr);
2254         if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) {
2255                 ret = -ENODEV;
2256                 goto out;
2257         }
2258         ifindex = imr->imr_ifindex;
2259         for (imlp = &inet->mc_list;
2260              (iml = rtnl_dereference(*imlp)) != NULL;
2261              imlp = &iml->next_rcu) {
2262                 if (iml->multi.imr_multiaddr.s_addr != group)
2263                         continue;
2264                 if (ifindex) {
2265                         if (iml->multi.imr_ifindex != ifindex)
2266                                 continue;
2267                 } else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
2268                                 iml->multi.imr_address.s_addr)
2269                         continue;
2270
2271                 (void) ip_mc_leave_src(sk, iml, in_dev);
2272
2273                 *imlp = iml->next_rcu;
2274
2275                 if (in_dev)
2276                         ip_mc_dec_group(in_dev, group);
2277
2278                 /* decrease mem now to avoid the memleak warning */
2279                 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2280                 kfree_rcu(iml, rcu);
2281                 return 0;
2282         }
2283 out:
2284         return ret;
2285 }
2286 EXPORT_SYMBOL(ip_mc_leave_group);
2287
2288 int ip_mc_source(int add, int omode, struct sock *sk, struct
2289         ip_mreq_source *mreqs, int ifindex)
2290 {
2291         int err;
2292         struct ip_mreqn imr;
2293         __be32 addr = mreqs->imr_multiaddr;
2294         struct ip_mc_socklist *pmc;
2295         struct in_device *in_dev = NULL;
2296         struct inet_sock *inet = inet_sk(sk);
2297         struct ip_sf_socklist *psl;
2298         struct net *net = sock_net(sk);
2299         int leavegroup = 0;
2300         int i, j, rv;
2301
2302         if (!ipv4_is_multicast(addr))
2303                 return -EINVAL;
2304
2305         ASSERT_RTNL();
2306
2307         imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
2308         imr.imr_address.s_addr = mreqs->imr_interface;
2309         imr.imr_ifindex = ifindex;
2310         in_dev = ip_mc_find_dev(net, &imr);
2311
2312         if (!in_dev) {
2313                 err = -ENODEV;
2314                 goto done;
2315         }
2316         err = -EADDRNOTAVAIL;
2317
2318         for_each_pmc_rtnl(inet, pmc) {
2319                 if ((pmc->multi.imr_multiaddr.s_addr ==
2320                      imr.imr_multiaddr.s_addr) &&
2321                     (pmc->multi.imr_ifindex == imr.imr_ifindex))
2322                         break;
2323         }
2324         if (!pmc) {             /* must have a prior join */
2325                 err = -EINVAL;
2326                 goto done;
2327         }
2328         /* if a source filter was set, must be the same mode as before */
2329         if (pmc->sflist) {
2330                 if (pmc->sfmode != omode) {
2331                         err = -EINVAL;
2332                         goto done;
2333                 }
2334         } else if (pmc->sfmode != omode) {
2335                 /* allow mode switches for empty-set filters */
2336                 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
2337                 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
2338                         NULL, 0);
2339                 pmc->sfmode = omode;
2340         }
2341
2342         psl = rtnl_dereference(pmc->sflist);
2343         if (!add) {
2344                 if (!psl)
2345                         goto done;      /* err = -EADDRNOTAVAIL */
2346                 rv = !0;
2347                 for (i = 0; i < psl->sl_count; i++) {
2348                         rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2349                                 sizeof(__be32));
2350                         if (rv == 0)
2351                                 break;
2352                 }
2353                 if (rv)         /* source not found */
2354                         goto done;      /* err = -EADDRNOTAVAIL */
2355
2356                 /* special case - (INCLUDE, empty) == LEAVE_GROUP */
2357                 if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
2358                         leavegroup = 1;
2359                         goto done;
2360                 }
2361
2362                 /* update the interface filter */
2363                 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2364                         &mreqs->imr_sourceaddr, 1);
2365
2366                 for (j = i+1; j < psl->sl_count; j++)
2367                         psl->sl_addr[j-1] = psl->sl_addr[j];
2368                 psl->sl_count--;
2369                 err = 0;
2370                 goto done;
2371         }
2372         /* else, add a new source to the filter */
2373
2374         if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) {
2375                 err = -ENOBUFS;
2376                 goto done;
2377         }
2378         if (!psl || psl->sl_count == psl->sl_max) {
2379                 struct ip_sf_socklist *newpsl;
2380                 int count = IP_SFBLOCK;
2381
2382                 if (psl)
2383                         count += psl->sl_max;
2384                 newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
2385                 if (!newpsl) {
2386                         err = -ENOBUFS;
2387                         goto done;
2388                 }
2389                 newpsl->sl_max = count;
2390                 newpsl->sl_count = count - IP_SFBLOCK;
2391                 if (psl) {
2392                         for (i = 0; i < psl->sl_count; i++)
2393                                 newpsl->sl_addr[i] = psl->sl_addr[i];
2394                         /* decrease mem now to avoid the memleak warning */
2395                         atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2396                         kfree_rcu(psl, rcu);
2397                 }
2398                 rcu_assign_pointer(pmc->sflist, newpsl);
2399                 psl = newpsl;
2400         }
2401         rv = 1; /* > 0 for insert logic below if sl_count is 0 */
2402         for (i = 0; i < psl->sl_count; i++) {
2403                 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2404                         sizeof(__be32));
2405                 if (rv == 0)
2406                         break;
2407         }
2408         if (rv == 0)            /* address already there is an error */
2409                 goto done;
2410         for (j = psl->sl_count-1; j >= i; j--)
2411                 psl->sl_addr[j+1] = psl->sl_addr[j];
2412         psl->sl_addr[i] = mreqs->imr_sourceaddr;
2413         psl->sl_count++;
2414         err = 0;
2415         /* update the interface list */
2416         ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2417                 &mreqs->imr_sourceaddr, 1);
2418 done:
2419         if (leavegroup)
2420                 err = ip_mc_leave_group(sk, &imr);
2421         return err;
2422 }
2423
2424 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2425 {
2426         int err = 0;
2427         struct ip_mreqn imr;
2428         __be32 addr = msf->imsf_multiaddr;
2429         struct ip_mc_socklist *pmc;
2430         struct in_device *in_dev;
2431         struct inet_sock *inet = inet_sk(sk);
2432         struct ip_sf_socklist *newpsl, *psl;
2433         struct net *net = sock_net(sk);
2434         int leavegroup = 0;
2435
2436         if (!ipv4_is_multicast(addr))
2437                 return -EINVAL;
2438         if (msf->imsf_fmode != MCAST_INCLUDE &&
2439             msf->imsf_fmode != MCAST_EXCLUDE)
2440                 return -EINVAL;
2441
2442         ASSERT_RTNL();
2443
2444         imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2445         imr.imr_address.s_addr = msf->imsf_interface;
2446         imr.imr_ifindex = ifindex;
2447         in_dev = ip_mc_find_dev(net, &imr);
2448
2449         if (!in_dev) {
2450                 err = -ENODEV;
2451                 goto done;
2452         }
2453
2454         /* special case - (INCLUDE, empty) == LEAVE_GROUP */
2455         if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2456                 leavegroup = 1;
2457                 goto done;
2458         }
2459
2460         for_each_pmc_rtnl(inet, pmc) {
2461                 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2462                     pmc->multi.imr_ifindex == imr.imr_ifindex)
2463                         break;
2464         }
2465         if (!pmc) {             /* must have a prior join */
2466                 err = -EINVAL;
2467                 goto done;
2468         }
2469         if (msf->imsf_numsrc) {
2470                 newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
2471                                                            GFP_KERNEL);
2472                 if (!newpsl) {
2473                         err = -ENOBUFS;
2474                         goto done;
2475                 }
2476                 newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2477                 memcpy(newpsl->sl_addr, msf->imsf_slist,
2478                         msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
2479                 err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2480                         msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2481                 if (err) {
2482                         sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
2483                         goto done;
2484                 }
2485         } else {
2486                 newpsl = NULL;
2487                 (void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2488                                      msf->imsf_fmode, 0, NULL, 0);
2489         }
2490         psl = rtnl_dereference(pmc->sflist);
2491         if (psl) {
2492                 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2493                         psl->sl_count, psl->sl_addr, 0);
2494                 /* decrease mem now to avoid the memleak warning */
2495                 atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
2496                 kfree_rcu(psl, rcu);
2497         } else
2498                 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2499                         0, NULL, 0);
2500         rcu_assign_pointer(pmc->sflist, newpsl);
2501         pmc->sfmode = msf->imsf_fmode;
2502         err = 0;
2503 done:
2504         if (leavegroup)
2505                 err = ip_mc_leave_group(sk, &imr);
2506         return err;
2507 }
2508
2509 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2510         struct ip_msfilter __user *optval, int __user *optlen)
2511 {
2512         int err, len, count, copycount;
2513         struct ip_mreqn imr;
2514         __be32 addr = msf->imsf_multiaddr;
2515         struct ip_mc_socklist *pmc;
2516         struct in_device *in_dev;
2517         struct inet_sock *inet = inet_sk(sk);
2518         struct ip_sf_socklist *psl;
2519         struct net *net = sock_net(sk);
2520
2521         ASSERT_RTNL();
2522
2523         if (!ipv4_is_multicast(addr))
2524                 return -EINVAL;
2525
2526         imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2527         imr.imr_address.s_addr = msf->imsf_interface;
2528         imr.imr_ifindex = 0;
2529         in_dev = ip_mc_find_dev(net, &imr);
2530
2531         if (!in_dev) {
2532                 err = -ENODEV;
2533                 goto done;
2534         }
2535         err = -EADDRNOTAVAIL;
2536
2537         for_each_pmc_rtnl(inet, pmc) {
2538                 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2539                     pmc->multi.imr_ifindex == imr.imr_ifindex)
2540                         break;
2541         }
2542         if (!pmc)               /* must have a prior join */
2543                 goto done;
2544         msf->imsf_fmode = pmc->sfmode;
2545         psl = rtnl_dereference(pmc->sflist);
2546         if (!psl) {
2547                 len = 0;
2548                 count = 0;
2549         } else {
2550                 count = psl->sl_count;
2551         }
2552         copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2553         len = copycount * sizeof(psl->sl_addr[0]);
2554         msf->imsf_numsrc = count;
2555         if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2556             copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2557                 return -EFAULT;
2558         }
2559         if (len &&
2560             copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
2561                 return -EFAULT;
2562         return 0;
2563 done:
2564         return err;
2565 }
2566
2567 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2568         struct sockaddr_storage __user *p)
2569 {
2570         int i, count, copycount;
2571         struct sockaddr_in *psin;
2572         __be32 addr;
2573         struct ip_mc_socklist *pmc;
2574         struct inet_sock *inet = inet_sk(sk);
2575         struct ip_sf_socklist *psl;
2576
2577         ASSERT_RTNL();
2578
2579         psin = (struct sockaddr_in *)&gsf->gf_group;
2580         if (psin->sin_family != AF_INET)
2581                 return -EINVAL;
2582         addr = psin->sin_addr.s_addr;
2583         if (!ipv4_is_multicast(addr))
2584                 return -EINVAL;
2585
2586         for_each_pmc_rtnl(inet, pmc) {
2587                 if (pmc->multi.imr_multiaddr.s_addr == addr &&
2588                     pmc->multi.imr_ifindex == gsf->gf_interface)
2589                         break;
2590         }
2591         if (!pmc)               /* must have a prior join */
2592                 return -EADDRNOTAVAIL;
2593         gsf->gf_fmode = pmc->sfmode;
2594         psl = rtnl_dereference(pmc->sflist);
2595         count = psl ? psl->sl_count : 0;
2596         copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2597         gsf->gf_numsrc = count;
2598         for (i = 0; i < copycount; i++, p++) {
2599                 struct sockaddr_storage ss;
2600
2601                 psin = (struct sockaddr_in *)&ss;
2602                 memset(&ss, 0, sizeof(ss));
2603                 psin->sin_family = AF_INET;
2604                 psin->sin_addr.s_addr = psl->sl_addr[i];
2605                 if (copy_to_user(p, &ss, sizeof(ss)))
2606                         return -EFAULT;
2607         }
2608         return 0;
2609 }
2610
2611 /*
2612  * check if a multicast source filter allows delivery for a given <src,dst,intf>
2613  */
2614 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr,
2615                    int dif, int sdif)
2616 {
2617         struct inet_sock *inet = inet_sk(sk);
2618         struct ip_mc_socklist *pmc;
2619         struct ip_sf_socklist *psl;
2620         int i;
2621         int ret;
2622
2623         ret = 1;
2624         if (!ipv4_is_multicast(loc_addr))
2625                 goto out;
2626
2627         rcu_read_lock();
2628         for_each_pmc_rcu(inet, pmc) {
2629                 if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2630                     (pmc->multi.imr_ifindex == dif ||
2631                      (sdif && pmc->multi.imr_ifindex == sdif)))
2632                         break;
2633         }
2634         ret = inet->mc_all;
2635         if (!pmc)
2636                 goto unlock;
2637         psl = rcu_dereference(pmc->sflist);
2638         ret = (pmc->sfmode == MCAST_EXCLUDE);
2639         if (!psl)
2640                 goto unlock;
2641
2642         for (i = 0; i < psl->sl_count; i++) {
2643                 if (psl->sl_addr[i] == rmt_addr)
2644                         break;
2645         }
2646         ret = 0;
2647         if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2648                 goto unlock;
2649         if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2650                 goto unlock;
2651         ret = 1;
2652 unlock:
2653         rcu_read_unlock();
2654 out:
2655         return ret;
2656 }
2657
2658 /*
2659  *      A socket is closing.
2660  */
2661
2662 void ip_mc_drop_socket(struct sock *sk)
2663 {
2664         struct inet_sock *inet = inet_sk(sk);
2665         struct ip_mc_socklist *iml;
2666         struct net *net = sock_net(sk);
2667
2668         if (!inet->mc_list)
2669                 return;
2670
2671         rtnl_lock();
2672         while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2673                 struct in_device *in_dev;
2674
2675                 inet->mc_list = iml->next_rcu;
2676                 in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2677                 (void) ip_mc_leave_src(sk, iml, in_dev);
2678                 if (in_dev)
2679                         ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2680                 /* decrease mem now to avoid the memleak warning */
2681                 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2682                 kfree_rcu(iml, rcu);
2683         }
2684         rtnl_unlock();
2685 }
2686
2687 /* called with rcu_read_lock() */
2688 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto)
2689 {
2690         struct ip_mc_list *im;
2691         struct ip_mc_list __rcu **mc_hash;
2692         struct ip_sf_list *psf;
2693         int rv = 0;
2694
2695         mc_hash = rcu_dereference(in_dev->mc_hash);
2696         if (mc_hash) {
2697                 u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
2698
2699                 for (im = rcu_dereference(mc_hash[hash]);
2700                      im != NULL;
2701                      im = rcu_dereference(im->next_hash)) {
2702                         if (im->multiaddr == mc_addr)
2703                                 break;
2704                 }
2705         } else {
2706                 for_each_pmc_rcu(in_dev, im) {
2707                         if (im->multiaddr == mc_addr)
2708                                 break;
2709                 }
2710         }
2711         if (im && proto == IPPROTO_IGMP) {
2712                 rv = 1;
2713         } else if (im) {
2714                 if (src_addr) {
2715                         for (psf = im->sources; psf; psf = psf->sf_next) {
2716                                 if (psf->sf_inaddr == src_addr)
2717                                         break;
2718                         }
2719                         if (psf)
2720                                 rv = psf->sf_count[MCAST_INCLUDE] ||
2721                                         psf->sf_count[MCAST_EXCLUDE] !=
2722                                         im->sfcount[MCAST_EXCLUDE];
2723                         else
2724                                 rv = im->sfcount[MCAST_EXCLUDE] != 0;
2725                 } else
2726                         rv = 1; /* unspecified source; tentatively allow */
2727         }
2728         return rv;
2729 }
2730
2731 #if defined(CONFIG_PROC_FS)
2732 struct igmp_mc_iter_state {
2733         struct seq_net_private p;
2734         struct net_device *dev;
2735         struct in_device *in_dev;
2736 };
2737
2738 #define igmp_mc_seq_private(seq)        ((struct igmp_mc_iter_state *)(seq)->private)
2739
2740 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2741 {
2742         struct net *net = seq_file_net(seq);
2743         struct ip_mc_list *im = NULL;
2744         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2745
2746         state->in_dev = NULL;
2747         for_each_netdev_rcu(net, state->dev) {
2748                 struct in_device *in_dev;
2749
2750                 in_dev = __in_dev_get_rcu(state->dev);
2751                 if (!in_dev)
2752                         continue;
2753                 im = rcu_dereference(in_dev->mc_list);
2754                 if (im) {
2755                         state->in_dev = in_dev;
2756                         break;
2757                 }
2758         }
2759         return im;
2760 }
2761
2762 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2763 {
2764         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2765
2766         im = rcu_dereference(im->next_rcu);
2767         while (!im) {
2768                 state->dev = next_net_device_rcu(state->dev);
2769                 if (!state->dev) {
2770                         state->in_dev = NULL;
2771                         break;
2772                 }
2773                 state->in_dev = __in_dev_get_rcu(state->dev);
2774                 if (!state->in_dev)
2775                         continue;
2776                 im = rcu_dereference(state->in_dev->mc_list);
2777         }
2778         return im;
2779 }
2780
2781 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2782 {
2783         struct ip_mc_list *im = igmp_mc_get_first(seq);
2784         if (im)
2785                 while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2786                         --pos;
2787         return pos ? NULL : im;
2788 }
2789
2790 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2791         __acquires(rcu)
2792 {
2793         rcu_read_lock();
2794         return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2795 }
2796
2797 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2798 {
2799         struct ip_mc_list *im;
2800         if (v == SEQ_START_TOKEN)
2801                 im = igmp_mc_get_first(seq);
2802         else
2803                 im = igmp_mc_get_next(seq, v);
2804         ++*pos;
2805         return im;
2806 }
2807
2808 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2809         __releases(rcu)
2810 {
2811         struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2812
2813         state->in_dev = NULL;
2814         state->dev = NULL;
2815         rcu_read_unlock();
2816 }
2817
2818 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2819 {
2820         if (v == SEQ_START_TOKEN)
2821                 seq_puts(seq,
2822                          "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
2823         else {
2824                 struct ip_mc_list *im = (struct ip_mc_list *)v;
2825                 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2826                 char   *querier;
2827                 long delta;
2828
2829 #ifdef CONFIG_IP_MULTICAST
2830                 querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2831                           IGMP_V2_SEEN(state->in_dev) ? "V2" :
2832                           "V3";
2833 #else
2834                 querier = "NONE";
2835 #endif
2836
2837                 if (rcu_access_pointer(state->in_dev->mc_list) == im) {
2838                         seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2839                                    state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2840                 }
2841
2842                 delta = im->timer.expires - jiffies;
2843                 seq_printf(seq,
2844                            "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2845                            im->multiaddr, im->users,
2846                            im->tm_running,
2847                            im->tm_running ? jiffies_delta_to_clock_t(delta) : 0,
2848                            im->reporter);
2849         }
2850         return 0;
2851 }
2852
2853 static const struct seq_operations igmp_mc_seq_ops = {
2854         .start  =       igmp_mc_seq_start,
2855         .next   =       igmp_mc_seq_next,
2856         .stop   =       igmp_mc_seq_stop,
2857         .show   =       igmp_mc_seq_show,
2858 };
2859
2860 struct igmp_mcf_iter_state {
2861         struct seq_net_private p;
2862         struct net_device *dev;
2863         struct in_device *idev;
2864         struct ip_mc_list *im;
2865 };
2866
2867 #define igmp_mcf_seq_private(seq)       ((struct igmp_mcf_iter_state *)(seq)->private)
2868
2869 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2870 {
2871         struct net *net = seq_file_net(seq);
2872         struct ip_sf_list *psf = NULL;
2873         struct ip_mc_list *im = NULL;
2874         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2875
2876         state->idev = NULL;
2877         state->im = NULL;
2878         for_each_netdev_rcu(net, state->dev) {
2879                 struct in_device *idev;
2880                 idev = __in_dev_get_rcu(state->dev);
2881                 if (unlikely(!idev))
2882                         continue;
2883                 im = rcu_dereference(idev->mc_list);
2884                 if (likely(im)) {
2885                         spin_lock_bh(&im->lock);
2886                         psf = im->sources;
2887                         if (likely(psf)) {
2888                                 state->im = im;
2889                                 state->idev = idev;
2890                                 break;
2891                         }
2892                         spin_unlock_bh(&im->lock);
2893                 }
2894         }
2895         return psf;
2896 }
2897
2898 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2899 {
2900         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2901
2902         psf = psf->sf_next;
2903         while (!psf) {
2904                 spin_unlock_bh(&state->im->lock);
2905                 state->im = state->im->next;
2906                 while (!state->im) {
2907                         state->dev = next_net_device_rcu(state->dev);
2908                         if (!state->dev) {
2909                                 state->idev = NULL;
2910                                 goto out;
2911                         }
2912                         state->idev = __in_dev_get_rcu(state->dev);
2913                         if (!state->idev)
2914                                 continue;
2915                         state->im = rcu_dereference(state->idev->mc_list);
2916                 }
2917                 if (!state->im)
2918                         break;
2919                 spin_lock_bh(&state->im->lock);
2920                 psf = state->im->sources;
2921         }
2922 out:
2923         return psf;
2924 }
2925
2926 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2927 {
2928         struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2929         if (psf)
2930                 while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2931                         --pos;
2932         return pos ? NULL : psf;
2933 }
2934
2935 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2936         __acquires(rcu)
2937 {
2938         rcu_read_lock();
2939         return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2940 }
2941
2942 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2943 {
2944         struct ip_sf_list *psf;
2945         if (v == SEQ_START_TOKEN)
2946                 psf = igmp_mcf_get_first(seq);
2947         else
2948                 psf = igmp_mcf_get_next(seq, v);
2949         ++*pos;
2950         return psf;
2951 }
2952
2953 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2954         __releases(rcu)
2955 {
2956         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2957         if (likely(state->im)) {
2958                 spin_unlock_bh(&state->im->lock);
2959                 state->im = NULL;
2960         }
2961         state->idev = NULL;
2962         state->dev = NULL;
2963         rcu_read_unlock();
2964 }
2965
2966 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2967 {
2968         struct ip_sf_list *psf = (struct ip_sf_list *)v;
2969         struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2970
2971         if (v == SEQ_START_TOKEN) {
2972                 seq_puts(seq, "Idx Device        MCA        SRC    INC    EXC\n");
2973         } else {
2974                 seq_printf(seq,
2975                            "%3d %6.6s 0x%08x "
2976                            "0x%08x %6lu %6lu\n",
2977                            state->dev->ifindex, state->dev->name,
2978                            ntohl(state->im->multiaddr),
2979                            ntohl(psf->sf_inaddr),
2980                            psf->sf_count[MCAST_INCLUDE],
2981                            psf->sf_count[MCAST_EXCLUDE]);
2982         }
2983         return 0;
2984 }
2985
2986 static const struct seq_operations igmp_mcf_seq_ops = {
2987         .start  =       igmp_mcf_seq_start,
2988         .next   =       igmp_mcf_seq_next,
2989         .stop   =       igmp_mcf_seq_stop,
2990         .show   =       igmp_mcf_seq_show,
2991 };
2992
2993 static int __net_init igmp_net_init(struct net *net)
2994 {
2995         struct proc_dir_entry *pde;
2996         int err;
2997
2998         pde = proc_create_net("igmp", 0444, net->proc_net, &igmp_mc_seq_ops,
2999                         sizeof(struct igmp_mc_iter_state));
3000         if (!pde)
3001                 goto out_igmp;
3002         pde = proc_create_net("mcfilter", 0444, net->proc_net,
3003                         &igmp_mcf_seq_ops, sizeof(struct igmp_mcf_iter_state));
3004         if (!pde)
3005                 goto out_mcfilter;
3006         err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET,
3007                                    SOCK_DGRAM, 0, net);
3008         if (err < 0) {
3009                 pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n",
3010                        err);
3011                 goto out_sock;
3012         }
3013
3014         return 0;
3015
3016 out_sock:
3017         remove_proc_entry("mcfilter", net->proc_net);
3018 out_mcfilter:
3019         remove_proc_entry("igmp", net->proc_net);
3020 out_igmp:
3021         return -ENOMEM;
3022 }
3023
3024 static void __net_exit igmp_net_exit(struct net *net)
3025 {
3026         remove_proc_entry("mcfilter", net->proc_net);
3027         remove_proc_entry("igmp", net->proc_net);
3028         inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk);
3029 }
3030
3031 static struct pernet_operations igmp_net_ops = {
3032         .init = igmp_net_init,
3033         .exit = igmp_net_exit,
3034 };
3035 #endif
3036
3037 static int igmp_netdev_event(struct notifier_block *this,
3038                              unsigned long event, void *ptr)
3039 {
3040         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3041         struct in_device *in_dev;
3042
3043         switch (event) {
3044         case NETDEV_RESEND_IGMP:
3045                 in_dev = __in_dev_get_rtnl(dev);
3046                 if (in_dev)
3047                         ip_mc_rejoin_groups(in_dev);
3048                 break;
3049         default:
3050                 break;
3051         }
3052         return NOTIFY_DONE;
3053 }
3054
3055 static struct notifier_block igmp_notifier = {
3056         .notifier_call = igmp_netdev_event,
3057 };
3058
3059 int __init igmp_mc_init(void)
3060 {
3061 #if defined(CONFIG_PROC_FS)
3062         int err;
3063
3064         err = register_pernet_subsys(&igmp_net_ops);
3065         if (err)
3066                 return err;
3067         err = register_netdevice_notifier(&igmp_notifier);
3068         if (err)
3069                 goto reg_notif_fail;
3070         return 0;
3071
3072 reg_notif_fail:
3073         unregister_pernet_subsys(&igmp_net_ops);
3074         return err;
3075 #else
3076         return register_netdevice_notifier(&igmp_notifier);
3077 #endif
3078 }