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 "igmp_internal.h" 85 #include <linux/if_arp.h> 86 #include <linux/rtnetlink.h> 87 #include <linux/times.h> 88 #include <linux/pkt_sched.h> 89 #include <linux/byteorder/generic.h> 90 91 #include <net/net_namespace.h> 92 #include <net/netlink.h> 93 #include <net/addrconf.h> 94 #include <net/arp.h> 95 #include <net/ip.h> 96 #include <net/protocol.h> 97 #include <net/route.h> 98 #include <net/sock.h> 99 #include <net/checksum.h> 100 #include <net/inet_common.h> 101 #include <linux/netfilter_ipv4.h> 102 #ifdef CONFIG_IP_MROUTE 103 #include <linux/mroute.h> 104 #endif 105 #ifdef CONFIG_PROC_FS 106 #include <linux/proc_fs.h> 107 #include <linux/seq_file.h> 108 #endif 109 110 #ifdef CONFIG_IP_MULTICAST 111 /* Parameter names and values are taken from igmp-v2-06 draft */ 112 113 #define IGMP_QUERY_INTERVAL (125*HZ) 114 #define IGMP_QUERY_RESPONSE_INTERVAL (10*HZ) 115 116 #define IGMP_INITIAL_REPORT_DELAY (1) 117 118 /* IGMP_INITIAL_REPORT_DELAY is not from IGMP specs! 119 * IGMP specs require to report membership immediately after 120 * joining a group, but we delay the first report by a 121 * small interval. It seems more natural and still does not 122 * contradict to specs provided this delay is small enough. 123 */ 124 125 static bool IGMP_V1_SEEN(const struct in_device *in_dev) 126 { 127 unsigned long seen; 128 129 if (IPV4_DEVCONF_ALL_RO(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1) 130 return true; 131 if (IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1) 132 return true; 133 seen = READ_ONCE(in_dev->mr_v1_seen); 134 return seen && time_before(jiffies, seen); 135 } 136 137 static bool IGMP_V2_SEEN(const struct in_device *in_dev) 138 { 139 unsigned long seen; 140 141 if (IPV4_DEVCONF_ALL_RO(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2) 142 return true; 143 if (IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2) 144 return true; 145 seen = READ_ONCE(in_dev->mr_v2_seen); 146 return seen && time_before(jiffies, seen); 147 } 148 149 static int unsolicited_report_interval(struct in_device *in_dev) 150 { 151 int interval_ms, interval_jiffies; 152 153 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) 154 interval_ms = IN_DEV_CONF_GET( 155 in_dev, 156 IGMPV2_UNSOLICITED_REPORT_INTERVAL); 157 else /* v3 */ 158 interval_ms = IN_DEV_CONF_GET( 159 in_dev, 160 IGMPV3_UNSOLICITED_REPORT_INTERVAL); 161 162 interval_jiffies = msecs_to_jiffies(interval_ms); 163 164 /* _timer functions can't handle a delay of 0 jiffies so ensure 165 * we always return a positive value. 166 */ 167 if (interval_jiffies <= 0) 168 interval_jiffies = 1; 169 return interval_jiffies; 170 } 171 172 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im, 173 gfp_t gfp); 174 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im); 175 static void igmpv3_clear_delrec(struct in_device *in_dev); 176 static int sf_setstate(struct ip_mc_list *pmc); 177 static void sf_markstate(struct ip_mc_list *pmc); 178 #endif 179 static void ip_mc_clear_src(struct ip_mc_list *pmc); 180 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 181 int sfcount, __be32 *psfsrc, int delta); 182 183 static void ip_ma_put(struct ip_mc_list *im) 184 { 185 if (refcount_dec_and_test(&im->refcnt)) { 186 in_dev_put(im->interface); 187 kfree_rcu(im, rcu); 188 } 189 } 190 191 #define for_each_pmc_rcu(in_dev, pmc) \ 192 for (pmc = rcu_dereference(in_dev->mc_list); \ 193 pmc != NULL; \ 194 pmc = rcu_dereference(pmc->next_rcu)) 195 196 #define for_each_pmc_rtnl(in_dev, pmc) \ 197 for (pmc = rtnl_dereference(in_dev->mc_list); \ 198 pmc != NULL; \ 199 pmc = rtnl_dereference(pmc->next_rcu)) 200 201 static void ip_sf_list_clear_all(struct ip_sf_list *psf) 202 { 203 struct ip_sf_list *next; 204 205 while (psf) { 206 next = psf->sf_next; 207 kfree(psf); 208 psf = next; 209 } 210 } 211 212 #ifdef CONFIG_IP_MULTICAST 213 214 /* 215 * Timer management 216 */ 217 218 static void igmp_stop_timer(struct ip_mc_list *im) 219 { 220 bool put = false; 221 222 spin_lock_bh(&im->lock); 223 if (timer_delete(&im->timer)) 224 put = true; 225 WRITE_ONCE(im->tm_running, 0); 226 WRITE_ONCE(im->reporter, 0); 227 im->unsolicit_count = 0; 228 spin_unlock_bh(&im->lock); 229 230 if (put) 231 ip_ma_put(im); 232 } 233 234 /* It must be called with locked im->lock */ 235 static void igmp_start_timer(struct ip_mc_list *im, int max_delay) 236 { 237 int tv = get_random_u32_below(max_delay); 238 239 WRITE_ONCE(im->tm_running, 1); 240 if (refcount_inc_not_zero(&im->refcnt)) { 241 if (mod_timer(&im->timer, jiffies + tv + 2)) 242 ip_ma_put(im); 243 } 244 } 245 246 static void igmp_gq_start_timer(struct in_device *in_dev) 247 { 248 int tv = get_random_u32_below(READ_ONCE(in_dev->mr_maxdelay)); 249 unsigned long exp = jiffies + tv + 2; 250 251 if (in_dev->mr_gq_running && 252 time_after_eq(exp, (in_dev->mr_gq_timer).expires)) 253 return; 254 255 in_dev->mr_gq_running = 1; 256 if (in_dev_hold_safe(in_dev)) { 257 if (mod_timer(&in_dev->mr_gq_timer, exp)) 258 in_dev_put(in_dev); 259 } 260 } 261 262 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay) 263 { 264 if (in_dev_hold_safe(in_dev)) { 265 int tv = get_random_u32_below(delay); 266 267 if (mod_timer(&in_dev->mr_ifc_timer, jiffies + tv + 2)) 268 in_dev_put(in_dev); 269 } 270 } 271 272 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay) 273 { 274 bool put = false; 275 276 spin_lock_bh(&im->lock); 277 im->unsolicit_count = 0; 278 if (timer_delete(&im->timer)) { 279 if ((long)(im->timer.expires-jiffies) < max_delay) { 280 add_timer(&im->timer); 281 WRITE_ONCE(im->tm_running, 1); 282 spin_unlock_bh(&im->lock); 283 return; 284 } 285 put = true; 286 } 287 igmp_start_timer(im, max_delay); 288 spin_unlock_bh(&im->lock); 289 290 if (put) 291 ip_ma_put(im); 292 } 293 294 295 /* 296 * Send an IGMP report. 297 */ 298 299 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4) 300 301 302 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type, 303 int gdeleted, int sdeleted) 304 { 305 switch (type) { 306 case IGMPV3_MODE_IS_INCLUDE: 307 case IGMPV3_MODE_IS_EXCLUDE: 308 if (gdeleted || sdeleted) 309 return 0; 310 if (!(pmc->gsquery && !psf->sf_gsresp)) { 311 if (pmc->sfmode == MCAST_INCLUDE) 312 return 1; 313 /* don't include if this source is excluded 314 * in all filters 315 */ 316 if (psf->sf_count[MCAST_INCLUDE]) 317 return type == IGMPV3_MODE_IS_INCLUDE; 318 return pmc->sfcount[MCAST_EXCLUDE] == 319 psf->sf_count[MCAST_EXCLUDE]; 320 } 321 return 0; 322 case IGMPV3_CHANGE_TO_INCLUDE: 323 if (gdeleted || sdeleted) 324 return 0; 325 return psf->sf_count[MCAST_INCLUDE] != 0; 326 case IGMPV3_CHANGE_TO_EXCLUDE: 327 if (gdeleted || sdeleted) 328 return 0; 329 if (pmc->sfcount[MCAST_EXCLUDE] == 0 || 330 psf->sf_count[MCAST_INCLUDE]) 331 return 0; 332 return pmc->sfcount[MCAST_EXCLUDE] == 333 psf->sf_count[MCAST_EXCLUDE]; 334 case IGMPV3_ALLOW_NEW_SOURCES: 335 if (gdeleted || !psf->sf_crcount) 336 return 0; 337 return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted; 338 case IGMPV3_BLOCK_OLD_SOURCES: 339 if (pmc->sfmode == MCAST_INCLUDE) 340 return gdeleted || (psf->sf_crcount && sdeleted); 341 return psf->sf_crcount && !gdeleted && !sdeleted; 342 } 343 return 0; 344 } 345 346 static int 347 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted) 348 { 349 struct ip_sf_list *psf; 350 int scount = 0; 351 352 for (psf = pmc->sources; psf; psf = psf->sf_next) { 353 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) 354 continue; 355 scount++; 356 } 357 return scount; 358 } 359 360 /* source address selection per RFC 3376 section 4.2.13 */ 361 static __be32 igmpv3_get_srcaddr(struct net_device *dev, 362 const struct flowi4 *fl4) 363 { 364 struct in_device *in_dev = __in_dev_get_rcu(dev); 365 const struct in_ifaddr *ifa; 366 367 if (!in_dev) 368 return htonl(INADDR_ANY); 369 370 in_dev_for_each_ifa_rcu(ifa, in_dev) { 371 if (fl4->saddr == ifa->ifa_local) 372 return fl4->saddr; 373 } 374 375 return htonl(INADDR_ANY); 376 } 377 378 static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu) 379 { 380 struct sk_buff *skb; 381 struct rtable *rt; 382 struct iphdr *pip; 383 struct igmpv3_report *pig; 384 struct net *net = dev_net(dev); 385 struct flowi4 fl4; 386 int hlen = LL_RESERVED_SPACE(dev); 387 int tlen = dev->needed_tailroom; 388 unsigned int size; 389 390 size = min(mtu, IP_MAX_MTU); 391 while (1) { 392 skb = alloc_skb(size + hlen + tlen, 393 GFP_ATOMIC | __GFP_NOWARN); 394 if (skb) 395 break; 396 size >>= 1; 397 if (size < 256) 398 return NULL; 399 } 400 skb->priority = TC_PRIO_CONTROL; 401 402 rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0, 403 0, 0, 404 IPPROTO_IGMP, 0, dev->ifindex); 405 if (IS_ERR(rt)) { 406 kfree_skb(skb); 407 return NULL; 408 } 409 410 skb_dst_set(skb, &rt->dst); 411 skb->dev = dev; 412 413 skb_reserve(skb, hlen); 414 skb_tailroom_reserve(skb, mtu, tlen); 415 416 skb_reset_network_header(skb); 417 pip = ip_hdr(skb); 418 skb_put(skb, sizeof(struct iphdr) + 4); 419 420 pip->version = 4; 421 pip->ihl = (sizeof(struct iphdr)+4)>>2; 422 pip->tos = 0xc0; 423 pip->frag_off = htons(IP_DF); 424 pip->ttl = 1; 425 pip->daddr = fl4.daddr; 426 427 rcu_read_lock(); 428 pip->saddr = igmpv3_get_srcaddr(dev, &fl4); 429 rcu_read_unlock(); 430 431 pip->protocol = IPPROTO_IGMP; 432 pip->tot_len = 0; /* filled in later */ 433 ip_select_ident(net, skb, NULL); 434 ((u8 *)&pip[1])[0] = IPOPT_RA; 435 ((u8 *)&pip[1])[1] = 4; 436 ((u8 *)&pip[1])[2] = 0; 437 ((u8 *)&pip[1])[3] = 0; 438 439 skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4; 440 skb_put(skb, sizeof(*pig)); 441 pig = igmpv3_report_hdr(skb); 442 pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT; 443 pig->resv1 = 0; 444 pig->csum = 0; 445 pig->resv2 = 0; 446 pig->ngrec = 0; 447 return skb; 448 } 449 450 static int igmpv3_sendpack(struct sk_buff *skb) 451 { 452 struct igmphdr *pig = igmp_hdr(skb); 453 const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb); 454 455 pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen); 456 457 return ip_local_out(skb_dst_dev_net(skb), skb->sk, skb); 458 } 459 460 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel) 461 { 462 return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel); 463 } 464 465 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc, 466 int type, struct igmpv3_grec **ppgr, unsigned int mtu) 467 { 468 struct net_device *dev = pmc->interface->dev; 469 struct igmpv3_report *pih; 470 struct igmpv3_grec *pgr; 471 472 if (!skb) { 473 skb = igmpv3_newpack(dev, mtu); 474 if (!skb) 475 return NULL; 476 } 477 pgr = skb_put(skb, sizeof(struct igmpv3_grec)); 478 pgr->grec_type = type; 479 pgr->grec_auxwords = 0; 480 pgr->grec_nsrcs = 0; 481 pgr->grec_mca = pmc->multiaddr; 482 pih = igmpv3_report_hdr(skb); 483 pih->ngrec = htons(ntohs(pih->ngrec)+1); 484 *ppgr = pgr; 485 return skb; 486 } 487 488 #define AVAILABLE(skb) ((skb) ? skb_availroom(skb) : 0) 489 490 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc, 491 int type, int gdeleted, int sdeleted) 492 { 493 struct net_device *dev = pmc->interface->dev; 494 struct net *net = dev_net(dev); 495 struct igmpv3_report *pih; 496 struct igmpv3_grec *pgr = NULL; 497 struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list; 498 int scount, stotal, first, isquery, truncate; 499 unsigned int mtu; 500 501 if (pmc->multiaddr == IGMP_ALL_HOSTS) 502 return skb; 503 if (ipv4_is_local_multicast(pmc->multiaddr) && 504 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) 505 return skb; 506 507 mtu = READ_ONCE(dev->mtu); 508 if (mtu < IPV4_MIN_MTU) 509 return skb; 510 511 isquery = type == IGMPV3_MODE_IS_INCLUDE || 512 type == IGMPV3_MODE_IS_EXCLUDE; 513 truncate = type == IGMPV3_MODE_IS_EXCLUDE || 514 type == IGMPV3_CHANGE_TO_EXCLUDE; 515 516 stotal = scount = 0; 517 518 psf_list = sdeleted ? &pmc->tomb : &pmc->sources; 519 520 if (!*psf_list) 521 goto empty_source; 522 523 pih = skb ? igmpv3_report_hdr(skb) : NULL; 524 525 /* EX and TO_EX get a fresh packet, if needed */ 526 if (truncate) { 527 if (pih && pih->ngrec && 528 AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) { 529 if (skb) 530 igmpv3_sendpack(skb); 531 skb = igmpv3_newpack(dev, mtu); 532 } 533 } 534 first = 1; 535 psf_prev = NULL; 536 for (psf = *psf_list; psf; psf = psf_next) { 537 __be32 *psrc; 538 539 psf_next = psf->sf_next; 540 541 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) { 542 psf_prev = psf; 543 continue; 544 } 545 546 /* Based on RFC3376 5.1. Should not send source-list change 547 * records when there is a filter mode change. 548 */ 549 if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) || 550 (!gdeleted && pmc->crcount)) && 551 (type == IGMPV3_ALLOW_NEW_SOURCES || 552 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) 553 goto decrease_sf_crcount; 554 555 /* clear marks on query responses */ 556 if (isquery) 557 psf->sf_gsresp = 0; 558 559 if (AVAILABLE(skb) < sizeof(__be32) + 560 first*sizeof(struct igmpv3_grec)) { 561 if (truncate && !first) 562 break; /* truncate these */ 563 if (pgr) 564 pgr->grec_nsrcs = htons(scount); 565 if (skb) 566 igmpv3_sendpack(skb); 567 skb = igmpv3_newpack(dev, mtu); 568 first = 1; 569 scount = 0; 570 } 571 if (first) { 572 skb = add_grhead(skb, pmc, type, &pgr, mtu); 573 first = 0; 574 } 575 if (!skb) 576 return NULL; 577 psrc = skb_put(skb, sizeof(__be32)); 578 *psrc = psf->sf_inaddr; 579 scount++; stotal++; 580 if ((type == IGMPV3_ALLOW_NEW_SOURCES || 581 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) { 582 decrease_sf_crcount: 583 psf->sf_crcount--; 584 if ((sdeleted || gdeleted) && psf->sf_crcount == 0) { 585 if (psf_prev) 586 psf_prev->sf_next = psf->sf_next; 587 else 588 *psf_list = psf->sf_next; 589 kfree(psf); 590 continue; 591 } 592 } 593 psf_prev = psf; 594 } 595 596 empty_source: 597 if (!stotal) { 598 if (type == IGMPV3_ALLOW_NEW_SOURCES || 599 type == IGMPV3_BLOCK_OLD_SOURCES) 600 return skb; 601 if (pmc->crcount || isquery) { 602 /* make sure we have room for group header */ 603 if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) { 604 igmpv3_sendpack(skb); 605 skb = NULL; /* add_grhead will get a new one */ 606 } 607 skb = add_grhead(skb, pmc, type, &pgr, mtu); 608 } 609 } 610 if (pgr) 611 pgr->grec_nsrcs = htons(scount); 612 613 if (isquery) 614 pmc->gsquery = 0; /* clear query state on report */ 615 return skb; 616 } 617 618 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc) 619 { 620 struct sk_buff *skb = NULL; 621 struct net *net = dev_net(in_dev->dev); 622 int type; 623 624 if (!pmc) { 625 rcu_read_lock(); 626 for_each_pmc_rcu(in_dev, pmc) { 627 if (pmc->multiaddr == IGMP_ALL_HOSTS) 628 continue; 629 if (ipv4_is_local_multicast(pmc->multiaddr) && 630 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) 631 continue; 632 spin_lock_bh(&pmc->lock); 633 if (pmc->sfcount[MCAST_EXCLUDE]) 634 type = IGMPV3_MODE_IS_EXCLUDE; 635 else 636 type = IGMPV3_MODE_IS_INCLUDE; 637 skb = add_grec(skb, pmc, type, 0, 0); 638 spin_unlock_bh(&pmc->lock); 639 } 640 rcu_read_unlock(); 641 } else { 642 spin_lock_bh(&pmc->lock); 643 if (pmc->sfcount[MCAST_EXCLUDE]) 644 type = IGMPV3_MODE_IS_EXCLUDE; 645 else 646 type = IGMPV3_MODE_IS_INCLUDE; 647 skb = add_grec(skb, pmc, type, 0, 0); 648 spin_unlock_bh(&pmc->lock); 649 } 650 if (!skb) 651 return 0; 652 return igmpv3_sendpack(skb); 653 } 654 655 /* 656 * remove zero-count source records from a source filter list 657 */ 658 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf) 659 { 660 struct ip_sf_list *psf_prev, *psf_next, *psf; 661 662 psf_prev = NULL; 663 for (psf = *ppsf; psf; psf = psf_next) { 664 psf_next = psf->sf_next; 665 if (psf->sf_crcount == 0) { 666 if (psf_prev) 667 psf_prev->sf_next = psf->sf_next; 668 else 669 *ppsf = psf->sf_next; 670 kfree(psf); 671 } else 672 psf_prev = psf; 673 } 674 } 675 676 static void kfree_pmc(struct ip_mc_list *pmc) 677 { 678 ip_sf_list_clear_all(pmc->sources); 679 ip_sf_list_clear_all(pmc->tomb); 680 kfree(pmc); 681 } 682 683 static void igmpv3_send_cr(struct in_device *in_dev) 684 { 685 struct ip_mc_list *pmc, *pmc_prev, *pmc_next; 686 struct sk_buff *skb = NULL; 687 int type, dtype; 688 689 rcu_read_lock(); 690 spin_lock_bh(&in_dev->mc_tomb_lock); 691 692 /* deleted MCA's */ 693 pmc_prev = NULL; 694 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) { 695 pmc_next = pmc->next; 696 if (pmc->sfmode == MCAST_INCLUDE) { 697 type = IGMPV3_BLOCK_OLD_SOURCES; 698 dtype = IGMPV3_BLOCK_OLD_SOURCES; 699 skb = add_grec(skb, pmc, type, 1, 0); 700 skb = add_grec(skb, pmc, dtype, 1, 1); 701 } 702 if (pmc->crcount) { 703 if (pmc->sfmode == MCAST_EXCLUDE) { 704 type = IGMPV3_CHANGE_TO_INCLUDE; 705 skb = add_grec(skb, pmc, type, 1, 0); 706 } 707 pmc->crcount--; 708 if (pmc->crcount == 0) { 709 igmpv3_clear_zeros(&pmc->tomb); 710 igmpv3_clear_zeros(&pmc->sources); 711 } 712 } 713 if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) { 714 if (pmc_prev) 715 pmc_prev->next = pmc_next; 716 else 717 in_dev->mc_tomb = pmc_next; 718 in_dev_put(pmc->interface); 719 kfree_pmc(pmc); 720 } else 721 pmc_prev = pmc; 722 } 723 spin_unlock_bh(&in_dev->mc_tomb_lock); 724 725 /* change recs */ 726 for_each_pmc_rcu(in_dev, pmc) { 727 spin_lock_bh(&pmc->lock); 728 if (pmc->sfcount[MCAST_EXCLUDE]) { 729 type = IGMPV3_BLOCK_OLD_SOURCES; 730 dtype = IGMPV3_ALLOW_NEW_SOURCES; 731 } else { 732 type = IGMPV3_ALLOW_NEW_SOURCES; 733 dtype = IGMPV3_BLOCK_OLD_SOURCES; 734 } 735 skb = add_grec(skb, pmc, type, 0, 0); 736 skb = add_grec(skb, pmc, dtype, 0, 1); /* deleted sources */ 737 738 /* filter mode changes */ 739 if (pmc->crcount) { 740 if (pmc->sfmode == MCAST_EXCLUDE) 741 type = IGMPV3_CHANGE_TO_EXCLUDE; 742 else 743 type = IGMPV3_CHANGE_TO_INCLUDE; 744 skb = add_grec(skb, pmc, type, 0, 0); 745 pmc->crcount--; 746 } 747 spin_unlock_bh(&pmc->lock); 748 } 749 rcu_read_unlock(); 750 751 if (!skb) 752 return; 753 (void) igmpv3_sendpack(skb); 754 } 755 756 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc, 757 int type) 758 { 759 struct sk_buff *skb; 760 struct iphdr *iph; 761 struct igmphdr *ih; 762 struct rtable *rt; 763 struct net_device *dev = in_dev->dev; 764 struct net *net = dev_net(dev); 765 __be32 group = pmc ? pmc->multiaddr : 0; 766 struct flowi4 fl4; 767 __be32 dst; 768 int hlen, tlen; 769 770 if (type == IGMPV3_HOST_MEMBERSHIP_REPORT) 771 return igmpv3_send_report(in_dev, pmc); 772 773 if (ipv4_is_local_multicast(group) && 774 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) 775 return 0; 776 777 if (type == IGMP_HOST_LEAVE_MESSAGE) 778 dst = IGMP_ALL_ROUTER; 779 else 780 dst = group; 781 782 rt = ip_route_output_ports(net, &fl4, NULL, dst, 0, 783 0, 0, 784 IPPROTO_IGMP, 0, dev->ifindex); 785 if (IS_ERR(rt)) 786 return -1; 787 788 hlen = LL_RESERVED_SPACE(dev); 789 tlen = dev->needed_tailroom; 790 skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC); 791 if (!skb) { 792 ip_rt_put(rt); 793 return -1; 794 } 795 skb->priority = TC_PRIO_CONTROL; 796 797 skb_dst_set(skb, &rt->dst); 798 799 skb_reserve(skb, hlen); 800 801 skb_reset_network_header(skb); 802 iph = ip_hdr(skb); 803 skb_put(skb, sizeof(struct iphdr) + 4); 804 805 iph->version = 4; 806 iph->ihl = (sizeof(struct iphdr)+4)>>2; 807 iph->tos = 0xc0; 808 iph->frag_off = htons(IP_DF); 809 iph->ttl = 1; 810 iph->daddr = dst; 811 iph->saddr = fl4.saddr; 812 iph->protocol = IPPROTO_IGMP; 813 ip_select_ident(net, skb, NULL); 814 ((u8 *)&iph[1])[0] = IPOPT_RA; 815 ((u8 *)&iph[1])[1] = 4; 816 ((u8 *)&iph[1])[2] = 0; 817 ((u8 *)&iph[1])[3] = 0; 818 819 ih = skb_put(skb, sizeof(struct igmphdr)); 820 ih->type = type; 821 ih->code = 0; 822 ih->csum = 0; 823 ih->group = group; 824 ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr)); 825 826 return ip_local_out(net, skb->sk, skb); 827 } 828 829 static void igmp_gq_timer_expire(struct timer_list *t) 830 { 831 struct in_device *in_dev = timer_container_of(in_dev, t, mr_gq_timer); 832 833 in_dev->mr_gq_running = 0; 834 igmpv3_send_report(in_dev, NULL); 835 in_dev_put(in_dev); 836 } 837 838 static void igmp_ifc_timer_expire(struct timer_list *t) 839 { 840 struct in_device *in_dev = timer_container_of(in_dev, t, mr_ifc_timer); 841 u32 mr_ifc_count; 842 843 igmpv3_send_cr(in_dev); 844 restart: 845 mr_ifc_count = READ_ONCE(in_dev->mr_ifc_count); 846 847 if (mr_ifc_count) { 848 if (cmpxchg(&in_dev->mr_ifc_count, 849 mr_ifc_count, 850 mr_ifc_count - 1) != mr_ifc_count) 851 goto restart; 852 igmp_ifc_start_timer(in_dev, 853 unsolicited_report_interval(in_dev)); 854 } 855 in_dev_put(in_dev); 856 } 857 858 static void igmp_ifc_event(struct in_device *in_dev) 859 { 860 struct net *net = dev_net(in_dev->dev); 861 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) 862 return; 863 WRITE_ONCE(in_dev->mr_ifc_count, in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv)); 864 igmp_ifc_start_timer(in_dev, 1); 865 } 866 867 868 static void igmp_timer_expire(struct timer_list *t) 869 { 870 struct ip_mc_list *im = timer_container_of(im, t, timer); 871 struct in_device *in_dev = im->interface; 872 873 spin_lock(&im->lock); 874 WRITE_ONCE(im->tm_running, 0); 875 876 if (im->unsolicit_count && --im->unsolicit_count) 877 igmp_start_timer(im, unsolicited_report_interval(in_dev)); 878 879 WRITE_ONCE(im->reporter, 1); 880 spin_unlock(&im->lock); 881 882 if (IGMP_V1_SEEN(in_dev)) 883 igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT); 884 else if (IGMP_V2_SEEN(in_dev)) 885 igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT); 886 else 887 igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT); 888 889 ip_ma_put(im); 890 } 891 892 /* mark EXCLUDE-mode sources */ 893 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs) 894 { 895 struct ip_sf_list *psf; 896 int i, scount; 897 898 scount = 0; 899 for (psf = pmc->sources; psf; psf = psf->sf_next) { 900 if (scount == nsrcs) 901 break; 902 for (i = 0; i < nsrcs; i++) { 903 /* skip inactive filters */ 904 if (psf->sf_count[MCAST_INCLUDE] || 905 pmc->sfcount[MCAST_EXCLUDE] != 906 psf->sf_count[MCAST_EXCLUDE]) 907 break; 908 if (srcs[i] == psf->sf_inaddr) { 909 scount++; 910 break; 911 } 912 } 913 } 914 pmc->gsquery = 0; 915 if (scount == nsrcs) /* all sources excluded */ 916 return 0; 917 return 1; 918 } 919 920 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs) 921 { 922 struct ip_sf_list *psf; 923 int i, scount; 924 925 if (pmc->sfmode == MCAST_EXCLUDE) 926 return igmp_xmarksources(pmc, nsrcs, srcs); 927 928 /* mark INCLUDE-mode sources */ 929 scount = 0; 930 for (psf = pmc->sources; psf; psf = psf->sf_next) { 931 if (scount == nsrcs) 932 break; 933 for (i = 0; i < nsrcs; i++) 934 if (srcs[i] == psf->sf_inaddr) { 935 psf->sf_gsresp = 1; 936 scount++; 937 break; 938 } 939 } 940 if (!scount) { 941 pmc->gsquery = 0; 942 return 0; 943 } 944 pmc->gsquery = 1; 945 return 1; 946 } 947 948 /* return true if packet was dropped */ 949 static bool igmp_heard_report(struct in_device *in_dev, __be32 group) 950 { 951 struct ip_mc_list *im; 952 struct net *net = dev_net(in_dev->dev); 953 954 /* Timers are only set for non-local groups */ 955 956 if (group == IGMP_ALL_HOSTS) 957 return false; 958 if (ipv4_is_local_multicast(group) && 959 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) 960 return false; 961 962 rcu_read_lock(); 963 for_each_pmc_rcu(in_dev, im) { 964 if (im->multiaddr == group) { 965 igmp_stop_timer(im); 966 break; 967 } 968 } 969 rcu_read_unlock(); 970 return false; 971 } 972 973 /* return true if packet was dropped */ 974 static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb, 975 int len) 976 { 977 struct igmphdr *ih = igmp_hdr(skb); 978 struct igmpv3_query *ih3 = igmpv3_query_hdr(skb); 979 struct ip_mc_list *im; 980 __be32 group = ih->group; 981 int max_delay; 982 int mark = 0; 983 struct net *net = dev_net(in_dev->dev); 984 unsigned long seen; 985 986 if (len == 8) { 987 seen = jiffies + READ_ONCE(in_dev->mr_qrv) * READ_ONCE(in_dev->mr_qi) + 988 READ_ONCE(in_dev->mr_qri); 989 if (ih->code == 0) { 990 /* Alas, old v1 router presents here. */ 991 992 max_delay = IGMP_QUERY_RESPONSE_INTERVAL; 993 WRITE_ONCE(in_dev->mr_v1_seen, seen); 994 group = 0; 995 } else { 996 /* v2 router present */ 997 max_delay = ih->code*(HZ/IGMP_TIMER_SCALE); 998 WRITE_ONCE(in_dev->mr_v2_seen, seen); 999 } 1000 /* cancel the interface change timer */ 1001 WRITE_ONCE(in_dev->mr_ifc_count, 0); 1002 if (timer_delete(&in_dev->mr_ifc_timer)) 1003 __in_dev_put(in_dev); 1004 /* clear deleted report items */ 1005 igmpv3_clear_delrec(in_dev); 1006 } else if (len < 12) { 1007 return true; /* ignore bogus packet; freed by caller */ 1008 } else if (IGMP_V1_SEEN(in_dev)) { 1009 /* This is a v3 query with v1 queriers present */ 1010 max_delay = IGMP_QUERY_RESPONSE_INTERVAL; 1011 group = 0; 1012 } else if (IGMP_V2_SEEN(in_dev)) { 1013 /* this is a v3 query with v2 queriers present; 1014 * Interpretation of the max_delay code is problematic here. 1015 * A real v2 host would use ih_code directly, while v3 has a 1016 * different encoding. We use the v3 encoding as more likely 1017 * to be intended in a v3 query. 1018 */ 1019 max_delay = igmpv3_mrt(ih3) * (HZ / IGMP_TIMER_SCALE); 1020 if (!max_delay) 1021 max_delay = 1; /* can't mod w/ 0 */ 1022 } else { /* v3 */ 1023 unsigned long mr_qi; 1024 1025 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) 1026 return true; 1027 1028 ih3 = igmpv3_query_hdr(skb); 1029 if (ih3->nsrcs) { 1030 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query) 1031 + ntohs(ih3->nsrcs)*sizeof(__be32))) 1032 return true; 1033 ih3 = igmpv3_query_hdr(skb); 1034 } 1035 1036 max_delay = igmpv3_mrt(ih3) * (HZ / IGMP_TIMER_SCALE); 1037 if (!max_delay) 1038 max_delay = 1; /* can't mod w/ 0 */ 1039 WRITE_ONCE(in_dev->mr_maxdelay, max_delay); 1040 1041 /* RFC3376, 4.1.6. QRV and 4.1.7. QQIC, when the most recently 1042 * received value was zero, use the default or statically 1043 * configured value. 1044 */ 1045 WRITE_ONCE(in_dev->mr_qrv, 1046 ih3->qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv)); 1047 mr_qi = igmpv3_qqi(ih3) * HZ ? : IGMP_QUERY_INTERVAL; 1048 WRITE_ONCE(in_dev->mr_qi, mr_qi); 1049 /* RFC3376, 8.3. Query Response Interval: 1050 * The number of seconds represented by the [Query Response 1051 * Interval] must be less than the [Query Interval]. 1052 */ 1053 if (READ_ONCE(in_dev->mr_qri) >= mr_qi) 1054 WRITE_ONCE(in_dev->mr_qri, (mr_qi/HZ - 1) * HZ); 1055 1056 if (!group) { /* general query */ 1057 if (ih3->nsrcs) 1058 return true; /* no sources allowed */ 1059 igmp_gq_start_timer(in_dev); 1060 return false; 1061 } 1062 /* mark sources to include, if group & source-specific */ 1063 mark = ih3->nsrcs != 0; 1064 } 1065 1066 /* 1067 * - Start the timers in all of our membership records 1068 * that the query applies to for the interface on 1069 * which the query arrived excl. those that belong 1070 * to a "local" group (224.0.0.X) 1071 * - For timers already running check if they need to 1072 * be reset. 1073 * - Use the igmp->igmp_code field as the maximum 1074 * delay possible 1075 */ 1076 rcu_read_lock(); 1077 for_each_pmc_rcu(in_dev, im) { 1078 int changed; 1079 1080 if (group && group != im->multiaddr) 1081 continue; 1082 if (im->multiaddr == IGMP_ALL_HOSTS) 1083 continue; 1084 if (ipv4_is_local_multicast(im->multiaddr) && 1085 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) 1086 continue; 1087 spin_lock_bh(&im->lock); 1088 if (im->tm_running) 1089 im->gsquery = im->gsquery && mark; 1090 else 1091 im->gsquery = mark; 1092 changed = !im->gsquery || 1093 igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs); 1094 spin_unlock_bh(&im->lock); 1095 if (changed) 1096 igmp_mod_timer(im, max_delay); 1097 } 1098 rcu_read_unlock(); 1099 return false; 1100 } 1101 1102 /* called in rcu_read_lock() section */ 1103 int igmp_rcv(struct sk_buff *skb) 1104 { 1105 /* This basically follows the spec line by line -- see RFC1112 */ 1106 struct igmphdr *ih; 1107 struct net_device *dev = skb->dev; 1108 struct in_device *in_dev; 1109 int len = skb->len; 1110 bool dropped = true; 1111 1112 if (netif_is_l3_master(dev)) { 1113 dev = dev_get_by_index_rcu(dev_net(dev), IPCB(skb)->iif); 1114 if (!dev) 1115 goto drop; 1116 } 1117 1118 in_dev = __in_dev_get_rcu(dev); 1119 if (!in_dev) 1120 goto drop; 1121 1122 if (!pskb_may_pull(skb, sizeof(struct igmphdr))) 1123 goto drop; 1124 1125 if (skb_checksum_simple_validate(skb)) 1126 goto drop; 1127 1128 ih = igmp_hdr(skb); 1129 switch (ih->type) { 1130 case IGMP_HOST_MEMBERSHIP_QUERY: 1131 dropped = igmp_heard_query(in_dev, skb, len); 1132 break; 1133 case IGMP_HOST_MEMBERSHIP_REPORT: 1134 case IGMPV2_HOST_MEMBERSHIP_REPORT: 1135 /* Is it our report looped back? */ 1136 if (rt_is_output_route(skb_rtable(skb))) 1137 break; 1138 /* don't rely on MC router hearing unicast reports */ 1139 if (skb->pkt_type == PACKET_MULTICAST || 1140 skb->pkt_type == PACKET_BROADCAST) 1141 dropped = igmp_heard_report(in_dev, ih->group); 1142 break; 1143 case IGMP_PIM: 1144 #ifdef CONFIG_IP_PIMSM_V1 1145 return pim_rcv_v1(skb); 1146 #endif 1147 case IGMPV3_HOST_MEMBERSHIP_REPORT: 1148 case IGMP_DVMRP: 1149 case IGMP_TRACE: 1150 case IGMP_HOST_LEAVE_MESSAGE: 1151 case IGMP_MTRACE: 1152 case IGMP_MTRACE_RESP: 1153 break; 1154 default: 1155 break; 1156 } 1157 1158 drop: 1159 if (dropped) 1160 kfree_skb(skb); 1161 else 1162 consume_skb(skb); 1163 return 0; 1164 } 1165 1166 #endif 1167 1168 1169 /* 1170 * Add a filter to a device 1171 */ 1172 1173 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr) 1174 { 1175 char buf[MAX_ADDR_LEN]; 1176 struct net_device *dev = in_dev->dev; 1177 1178 /* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG. 1179 We will get multicast token leakage, when IFF_MULTICAST 1180 is changed. This check should be done in ndo_set_rx_mode 1181 routine. Something sort of: 1182 if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; } 1183 --ANK 1184 */ 1185 if (arp_mc_map(addr, buf, dev, 0) == 0) 1186 dev_mc_add(dev, buf); 1187 } 1188 1189 /* 1190 * Remove a filter from a device 1191 */ 1192 1193 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr) 1194 { 1195 char buf[MAX_ADDR_LEN]; 1196 struct net_device *dev = in_dev->dev; 1197 1198 if (arp_mc_map(addr, buf, dev, 0) == 0) 1199 dev_mc_del(dev, buf); 1200 } 1201 1202 #ifdef CONFIG_IP_MULTICAST 1203 /* 1204 * deleted ip_mc_list manipulation 1205 */ 1206 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im, 1207 gfp_t gfp) 1208 { 1209 struct ip_mc_list *pmc; 1210 struct net *net = dev_net(in_dev->dev); 1211 1212 /* this is an "ip_mc_list" for convenience; only the fields below 1213 * are actually used. In particular, the refcnt and users are not 1214 * used for management of the delete list. Using the same structure 1215 * for deleted items allows change reports to use common code with 1216 * non-deleted or query-response MCA's. 1217 */ 1218 pmc = kzalloc_obj(*pmc, gfp); 1219 if (!pmc) 1220 return; 1221 spin_lock_init(&pmc->lock); 1222 spin_lock_bh(&im->lock); 1223 pmc->interface = im->interface; 1224 in_dev_hold(in_dev); 1225 pmc->multiaddr = im->multiaddr; 1226 pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); 1227 pmc->sfmode = im->sfmode; 1228 if (pmc->sfmode == MCAST_INCLUDE) { 1229 struct ip_sf_list *psf; 1230 1231 pmc->tomb = im->tomb; 1232 pmc->sources = im->sources; 1233 im->tomb = im->sources = NULL; 1234 for (psf = pmc->sources; psf; psf = psf->sf_next) 1235 psf->sf_crcount = pmc->crcount; 1236 } 1237 spin_unlock_bh(&im->lock); 1238 1239 spin_lock_bh(&in_dev->mc_tomb_lock); 1240 pmc->next = in_dev->mc_tomb; 1241 in_dev->mc_tomb = pmc; 1242 spin_unlock_bh(&in_dev->mc_tomb_lock); 1243 } 1244 1245 /* 1246 * restore ip_mc_list deleted records 1247 */ 1248 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im) 1249 { 1250 struct ip_mc_list *pmc, *pmc_prev; 1251 struct ip_sf_list *psf; 1252 struct net *net = dev_net(in_dev->dev); 1253 __be32 multiaddr = im->multiaddr; 1254 1255 spin_lock_bh(&in_dev->mc_tomb_lock); 1256 pmc_prev = NULL; 1257 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) { 1258 if (pmc->multiaddr == multiaddr) 1259 break; 1260 pmc_prev = pmc; 1261 } 1262 if (pmc) { 1263 if (pmc_prev) 1264 pmc_prev->next = pmc->next; 1265 else 1266 in_dev->mc_tomb = pmc->next; 1267 } 1268 spin_unlock_bh(&in_dev->mc_tomb_lock); 1269 1270 spin_lock_bh(&im->lock); 1271 if (pmc) { 1272 im->interface = pmc->interface; 1273 if (im->sfmode == MCAST_INCLUDE) { 1274 swap(im->tomb, pmc->tomb); 1275 swap(im->sources, pmc->sources); 1276 for (psf = im->sources; psf; psf = psf->sf_next) 1277 psf->sf_crcount = in_dev->mr_qrv ?: 1278 READ_ONCE(net->ipv4.sysctl_igmp_qrv); 1279 } else { 1280 im->crcount = in_dev->mr_qrv ?: 1281 READ_ONCE(net->ipv4.sysctl_igmp_qrv); 1282 } 1283 in_dev_put(pmc->interface); 1284 kfree_pmc(pmc); 1285 } 1286 spin_unlock_bh(&im->lock); 1287 } 1288 1289 /* 1290 * flush ip_mc_list deleted records 1291 */ 1292 static void igmpv3_clear_delrec(struct in_device *in_dev) 1293 { 1294 struct ip_mc_list *pmc, *nextpmc; 1295 1296 spin_lock_bh(&in_dev->mc_tomb_lock); 1297 pmc = in_dev->mc_tomb; 1298 in_dev->mc_tomb = NULL; 1299 spin_unlock_bh(&in_dev->mc_tomb_lock); 1300 1301 for (; pmc; pmc = nextpmc) { 1302 nextpmc = pmc->next; 1303 ip_mc_clear_src(pmc); 1304 in_dev_put(pmc->interface); 1305 kfree_pmc(pmc); 1306 } 1307 /* clear dead sources, too */ 1308 rcu_read_lock(); 1309 for_each_pmc_rcu(in_dev, pmc) { 1310 struct ip_sf_list *psf; 1311 1312 spin_lock_bh(&pmc->lock); 1313 psf = pmc->tomb; 1314 pmc->tomb = NULL; 1315 spin_unlock_bh(&pmc->lock); 1316 ip_sf_list_clear_all(psf); 1317 } 1318 rcu_read_unlock(); 1319 } 1320 #endif 1321 1322 static void __igmp_group_dropped(struct ip_mc_list *im, gfp_t gfp) 1323 { 1324 struct in_device *in_dev = im->interface; 1325 #ifdef CONFIG_IP_MULTICAST 1326 struct net *net = dev_net(in_dev->dev); 1327 int reporter; 1328 #endif 1329 1330 if (im->loaded) { 1331 im->loaded = 0; 1332 ip_mc_filter_del(in_dev, im->multiaddr); 1333 } 1334 1335 #ifdef CONFIG_IP_MULTICAST 1336 if (im->multiaddr == IGMP_ALL_HOSTS) 1337 return; 1338 if (ipv4_is_local_multicast(im->multiaddr) && 1339 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) 1340 return; 1341 1342 reporter = READ_ONCE(im->reporter); 1343 igmp_stop_timer(im); 1344 1345 if (!in_dev->dead) { 1346 if (IGMP_V1_SEEN(in_dev)) 1347 return; 1348 if (IGMP_V2_SEEN(in_dev)) { 1349 if (reporter) 1350 igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE); 1351 return; 1352 } 1353 /* IGMPv3 */ 1354 igmpv3_add_delrec(in_dev, im, gfp); 1355 1356 igmp_ifc_event(in_dev); 1357 } 1358 #endif 1359 } 1360 1361 static void igmp_group_dropped(struct ip_mc_list *im) 1362 { 1363 __igmp_group_dropped(im, GFP_KERNEL); 1364 } 1365 1366 static void igmp_group_added(struct ip_mc_list *im) 1367 { 1368 struct in_device *in_dev = im->interface; 1369 #ifdef CONFIG_IP_MULTICAST 1370 struct net *net = dev_net(in_dev->dev); 1371 #endif 1372 1373 if (im->loaded == 0) { 1374 im->loaded = 1; 1375 ip_mc_filter_add(in_dev, im->multiaddr); 1376 } 1377 1378 #ifdef CONFIG_IP_MULTICAST 1379 if (im->multiaddr == IGMP_ALL_HOSTS) 1380 return; 1381 if (ipv4_is_local_multicast(im->multiaddr) && 1382 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) 1383 return; 1384 1385 if (in_dev->dead) 1386 return; 1387 1388 im->unsolicit_count = READ_ONCE(net->ipv4.sysctl_igmp_qrv); 1389 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) { 1390 spin_lock_bh(&im->lock); 1391 igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY); 1392 spin_unlock_bh(&im->lock); 1393 return; 1394 } 1395 /* else, v3 */ 1396 1397 /* Based on RFC3376 5.1, for newly added INCLUDE SSM, we should 1398 * not send filter-mode change record as the mode should be from 1399 * IN() to IN(A). 1400 */ 1401 if (im->sfmode == MCAST_EXCLUDE) 1402 im->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); 1403 1404 igmp_ifc_event(in_dev); 1405 #endif 1406 } 1407 1408 1409 /* 1410 * Multicast list managers 1411 */ 1412 1413 static u32 ip_mc_hash(const struct ip_mc_list *im) 1414 { 1415 return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG); 1416 } 1417 1418 static void ip_mc_hash_add(struct in_device *in_dev, 1419 struct ip_mc_list *im) 1420 { 1421 struct ip_mc_list __rcu **mc_hash; 1422 u32 hash; 1423 1424 mc_hash = rtnl_dereference(in_dev->mc_hash); 1425 if (mc_hash) { 1426 hash = ip_mc_hash(im); 1427 im->next_hash = mc_hash[hash]; 1428 rcu_assign_pointer(mc_hash[hash], im); 1429 return; 1430 } 1431 1432 /* do not use a hash table for small number of items */ 1433 if (in_dev->mc_count < 4) 1434 return; 1435 1436 mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG, 1437 GFP_KERNEL); 1438 if (!mc_hash) 1439 return; 1440 1441 for_each_pmc_rtnl(in_dev, im) { 1442 hash = ip_mc_hash(im); 1443 im->next_hash = mc_hash[hash]; 1444 RCU_INIT_POINTER(mc_hash[hash], im); 1445 } 1446 1447 rcu_assign_pointer(in_dev->mc_hash, mc_hash); 1448 } 1449 1450 static void ip_mc_hash_remove(struct in_device *in_dev, 1451 struct ip_mc_list *im) 1452 { 1453 struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash); 1454 struct ip_mc_list *aux; 1455 1456 if (!mc_hash) 1457 return; 1458 mc_hash += ip_mc_hash(im); 1459 while ((aux = rtnl_dereference(*mc_hash)) != im) 1460 mc_hash = &aux->next_hash; 1461 *mc_hash = im->next_hash; 1462 } 1463 1464 int inet_fill_ifmcaddr(struct sk_buff *skb, struct net_device *dev, 1465 const struct ip_mc_list *im, 1466 struct inet_fill_args *args) 1467 { 1468 struct ifa_cacheinfo ci; 1469 struct ifaddrmsg *ifm; 1470 struct nlmsghdr *nlh; 1471 1472 nlh = nlmsg_put(skb, args->portid, args->seq, args->event, 1473 sizeof(struct ifaddrmsg), args->flags); 1474 if (!nlh) 1475 return -EMSGSIZE; 1476 1477 ifm = nlmsg_data(nlh); 1478 ifm->ifa_family = AF_INET; 1479 ifm->ifa_prefixlen = 32; 1480 ifm->ifa_flags = IFA_F_PERMANENT; 1481 ifm->ifa_scope = RT_SCOPE_UNIVERSE; 1482 ifm->ifa_index = dev->ifindex; 1483 1484 ci.cstamp = (READ_ONCE(im->mca_cstamp) - INITIAL_JIFFIES) * 100UL / HZ; 1485 ci.tstamp = ci.cstamp; 1486 ci.ifa_prefered = INFINITY_LIFE_TIME; 1487 ci.ifa_valid = INFINITY_LIFE_TIME; 1488 1489 if (nla_put_in_addr(skb, IFA_MULTICAST, im->multiaddr) < 0 || 1490 nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci) < 0) { 1491 nlmsg_cancel(skb, nlh); 1492 return -EMSGSIZE; 1493 } 1494 1495 nlmsg_end(skb, nlh); 1496 return 0; 1497 } 1498 1499 static void inet_ifmcaddr_notify(struct net_device *dev, 1500 const struct ip_mc_list *im, int event) 1501 { 1502 struct inet_fill_args fillargs = { 1503 .event = event, 1504 }; 1505 struct net *net = dev_net(dev); 1506 struct sk_buff *skb; 1507 int err = -ENOMEM; 1508 1509 skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) + 1510 nla_total_size(sizeof(__be32)) + 1511 nla_total_size(sizeof(struct ifa_cacheinfo)), 1512 GFP_KERNEL); 1513 if (!skb) 1514 goto error; 1515 1516 err = inet_fill_ifmcaddr(skb, dev, im, &fillargs); 1517 if (err < 0) { 1518 WARN_ON_ONCE(err == -EMSGSIZE); 1519 nlmsg_free(skb); 1520 goto error; 1521 } 1522 1523 rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MCADDR, NULL, GFP_KERNEL); 1524 return; 1525 error: 1526 rtnl_set_sk_err(net, RTNLGRP_IPV4_MCADDR, err); 1527 } 1528 1529 /* 1530 * A socket has joined a multicast group on device dev. 1531 */ 1532 static void ____ip_mc_inc_group(struct in_device *in_dev, __be32 addr, 1533 unsigned int mode, gfp_t gfp) 1534 { 1535 struct ip_mc_list __rcu **mc_hash; 1536 struct ip_mc_list *im; 1537 1538 ASSERT_RTNL(); 1539 1540 mc_hash = rtnl_dereference(in_dev->mc_hash); 1541 if (mc_hash) { 1542 u32 hash = hash_32((__force u32)addr, MC_HASH_SZ_LOG); 1543 1544 for (im = rtnl_dereference(mc_hash[hash]); 1545 im; 1546 im = rtnl_dereference(im->next_hash)) { 1547 if (im->multiaddr == addr) 1548 break; 1549 } 1550 } else { 1551 for_each_pmc_rtnl(in_dev, im) { 1552 if (im->multiaddr == addr) 1553 break; 1554 } 1555 } 1556 1557 if (im) { 1558 WRITE_ONCE(im->users, im->users + 1); 1559 ip_mc_add_src(in_dev, &addr, mode, 0, NULL, 0); 1560 goto out; 1561 } 1562 1563 im = kzalloc_obj(*im, gfp); 1564 if (!im) 1565 goto out; 1566 1567 WRITE_ONCE(im->users, 1); 1568 im->interface = in_dev; 1569 in_dev_hold(in_dev); 1570 im->multiaddr = addr; 1571 im->mca_cstamp = jiffies; 1572 im->mca_tstamp = im->mca_cstamp; 1573 /* initial mode is (EX, empty) */ 1574 im->sfmode = mode; 1575 im->sfcount[mode] = 1; 1576 refcount_set(&im->refcnt, 1); 1577 spin_lock_init(&im->lock); 1578 #ifdef CONFIG_IP_MULTICAST 1579 timer_setup(&im->timer, igmp_timer_expire, 0); 1580 #endif 1581 1582 im->next_rcu = in_dev->mc_list; 1583 WRITE_ONCE(in_dev->mc_count, in_dev->mc_count + 1); 1584 rcu_assign_pointer(in_dev->mc_list, im); 1585 1586 ip_mc_hash_add(in_dev, im); 1587 1588 #ifdef CONFIG_IP_MULTICAST 1589 igmpv3_del_delrec(in_dev, im); 1590 #endif 1591 igmp_group_added(im); 1592 inet_ifmcaddr_notify(in_dev->dev, im, RTM_NEWMULTICAST); 1593 if (!in_dev->dead) 1594 ip_rt_multicast_event(in_dev); 1595 out: 1596 return; 1597 } 1598 1599 void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr, gfp_t gfp) 1600 { 1601 ____ip_mc_inc_group(in_dev, addr, MCAST_EXCLUDE, gfp); 1602 } 1603 EXPORT_SYMBOL(__ip_mc_inc_group); 1604 1605 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr) 1606 { 1607 __ip_mc_inc_group(in_dev, addr, GFP_KERNEL); 1608 } 1609 EXPORT_SYMBOL(ip_mc_inc_group); 1610 1611 static int ip_mc_check_iphdr(struct sk_buff *skb) 1612 { 1613 const struct iphdr *iph; 1614 unsigned int len; 1615 unsigned int offset = skb_network_offset(skb) + sizeof(*iph); 1616 1617 if (!pskb_may_pull(skb, offset)) 1618 return -EINVAL; 1619 1620 iph = ip_hdr(skb); 1621 1622 if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph)) 1623 return -EINVAL; 1624 1625 offset += ip_hdrlen(skb) - sizeof(*iph); 1626 1627 if (!pskb_may_pull(skb, offset)) 1628 return -EINVAL; 1629 1630 iph = ip_hdr(skb); 1631 1632 if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl))) 1633 return -EINVAL; 1634 1635 len = skb_network_offset(skb) + ntohs(iph->tot_len); 1636 if (skb->len < len || len < offset) 1637 return -EINVAL; 1638 1639 skb_set_transport_header(skb, offset); 1640 1641 return 0; 1642 } 1643 1644 static int ip_mc_check_igmp_reportv3(struct sk_buff *skb) 1645 { 1646 unsigned int len = skb_transport_offset(skb); 1647 1648 len += sizeof(struct igmpv3_report); 1649 1650 return ip_mc_may_pull(skb, len) ? 0 : -EINVAL; 1651 } 1652 1653 static int ip_mc_check_igmp_query(struct sk_buff *skb) 1654 { 1655 unsigned int transport_len = ip_transport_len(skb); 1656 unsigned int len; 1657 1658 /* IGMPv{1,2}? */ 1659 if (transport_len != sizeof(struct igmphdr)) { 1660 /* or IGMPv3? */ 1661 if (transport_len < sizeof(struct igmpv3_query)) 1662 return -EINVAL; 1663 1664 len = skb_transport_offset(skb) + sizeof(struct igmpv3_query); 1665 if (!ip_mc_may_pull(skb, len)) 1666 return -EINVAL; 1667 } 1668 1669 /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer 1670 * all-systems destination addresses (224.0.0.1) for general queries 1671 */ 1672 if (!igmp_hdr(skb)->group && 1673 ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP)) 1674 return -EINVAL; 1675 1676 return 0; 1677 } 1678 1679 static int ip_mc_check_igmp_msg(struct sk_buff *skb) 1680 { 1681 switch (igmp_hdr(skb)->type) { 1682 case IGMP_HOST_LEAVE_MESSAGE: 1683 case IGMP_HOST_MEMBERSHIP_REPORT: 1684 case IGMPV2_HOST_MEMBERSHIP_REPORT: 1685 return 0; 1686 case IGMPV3_HOST_MEMBERSHIP_REPORT: 1687 return ip_mc_check_igmp_reportv3(skb); 1688 case IGMP_HOST_MEMBERSHIP_QUERY: 1689 return ip_mc_check_igmp_query(skb); 1690 default: 1691 return -ENOMSG; 1692 } 1693 } 1694 1695 static __sum16 ip_mc_validate_checksum(struct sk_buff *skb) 1696 { 1697 return skb_checksum_simple_validate(skb); 1698 } 1699 1700 static int ip_mc_check_igmp_csum(struct sk_buff *skb) 1701 { 1702 unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr); 1703 unsigned int transport_len = ip_transport_len(skb); 1704 struct sk_buff *skb_chk; 1705 1706 if (!ip_mc_may_pull(skb, len)) 1707 return -EINVAL; 1708 1709 skb_chk = skb_checksum_trimmed(skb, transport_len, 1710 ip_mc_validate_checksum); 1711 if (!skb_chk) 1712 return -EINVAL; 1713 1714 if (skb_chk != skb) 1715 kfree_skb(skb_chk); 1716 1717 return 0; 1718 } 1719 1720 /** 1721 * ip_mc_check_igmp - checks whether this is a sane IGMP packet 1722 * @skb: the skb to validate 1723 * 1724 * Checks whether an IPv4 packet is a valid IGMP packet. If so sets 1725 * skb transport header accordingly and returns zero. 1726 * 1727 * -EINVAL: A broken packet was detected, i.e. it violates some internet 1728 * standard 1729 * -ENOMSG: IP header validation succeeded but it is not an IGMP packet. 1730 * -ENOMEM: A memory allocation failure happened. 1731 * 1732 * Caller needs to set the skb network header and free any returned skb if it 1733 * differs from the provided skb. 1734 */ 1735 int ip_mc_check_igmp(struct sk_buff *skb) 1736 { 1737 int ret = ip_mc_check_iphdr(skb); 1738 1739 if (ret < 0) 1740 return ret; 1741 1742 if (ip_hdr(skb)->protocol != IPPROTO_IGMP) 1743 return -ENOMSG; 1744 1745 ret = ip_mc_check_igmp_csum(skb); 1746 if (ret < 0) 1747 return ret; 1748 1749 return ip_mc_check_igmp_msg(skb); 1750 } 1751 EXPORT_SYMBOL(ip_mc_check_igmp); 1752 1753 /* 1754 * Resend IGMP JOIN report; used by netdev notifier. 1755 */ 1756 static void ip_mc_rejoin_groups(struct in_device *in_dev) 1757 { 1758 #ifdef CONFIG_IP_MULTICAST 1759 struct ip_mc_list *im; 1760 int type; 1761 struct net *net = dev_net(in_dev->dev); 1762 1763 ASSERT_RTNL(); 1764 1765 for_each_pmc_rtnl(in_dev, im) { 1766 if (im->multiaddr == IGMP_ALL_HOSTS) 1767 continue; 1768 if (ipv4_is_local_multicast(im->multiaddr) && 1769 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) 1770 continue; 1771 1772 /* a failover is happening and switches 1773 * must be notified immediately 1774 */ 1775 if (IGMP_V1_SEEN(in_dev)) 1776 type = IGMP_HOST_MEMBERSHIP_REPORT; 1777 else if (IGMP_V2_SEEN(in_dev)) 1778 type = IGMPV2_HOST_MEMBERSHIP_REPORT; 1779 else 1780 type = IGMPV3_HOST_MEMBERSHIP_REPORT; 1781 igmp_send_report(in_dev, im, type); 1782 } 1783 #endif 1784 } 1785 1786 /* 1787 * A socket has left a multicast group on device dev 1788 */ 1789 1790 void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp) 1791 { 1792 struct ip_mc_list *i; 1793 struct ip_mc_list __rcu **ip; 1794 1795 ASSERT_RTNL(); 1796 1797 for (ip = &in_dev->mc_list; 1798 (i = rtnl_dereference(*ip)) != NULL; 1799 ip = &i->next_rcu) { 1800 if (i->multiaddr == addr) { 1801 int new_users = i->users - 1; 1802 1803 WRITE_ONCE(i->users, new_users); 1804 if (new_users == 0) { 1805 ip_mc_hash_remove(in_dev, i); 1806 *ip = i->next_rcu; 1807 WRITE_ONCE(in_dev->mc_count, 1808 in_dev->mc_count - 1); 1809 __igmp_group_dropped(i, gfp); 1810 inet_ifmcaddr_notify(in_dev->dev, i, 1811 RTM_DELMULTICAST); 1812 ip_mc_clear_src(i); 1813 1814 if (!in_dev->dead) 1815 ip_rt_multicast_event(in_dev); 1816 1817 ip_ma_put(i); 1818 return; 1819 } 1820 break; 1821 } 1822 } 1823 } 1824 EXPORT_SYMBOL(__ip_mc_dec_group); 1825 1826 /* Device changing type */ 1827 1828 void ip_mc_unmap(struct in_device *in_dev) 1829 { 1830 struct ip_mc_list *pmc; 1831 1832 ASSERT_RTNL(); 1833 1834 for_each_pmc_rtnl(in_dev, pmc) 1835 igmp_group_dropped(pmc); 1836 } 1837 1838 void ip_mc_remap(struct in_device *in_dev) 1839 { 1840 struct ip_mc_list *pmc; 1841 1842 ASSERT_RTNL(); 1843 1844 for_each_pmc_rtnl(in_dev, pmc) { 1845 #ifdef CONFIG_IP_MULTICAST 1846 igmpv3_del_delrec(in_dev, pmc); 1847 #endif 1848 igmp_group_added(pmc); 1849 } 1850 } 1851 1852 /* Device going down */ 1853 1854 void ip_mc_down(struct in_device *in_dev) 1855 { 1856 struct ip_mc_list *pmc; 1857 1858 ASSERT_RTNL(); 1859 1860 for_each_pmc_rtnl(in_dev, pmc) 1861 igmp_group_dropped(pmc); 1862 1863 #ifdef CONFIG_IP_MULTICAST 1864 WRITE_ONCE(in_dev->mr_ifc_count, 0); 1865 if (timer_delete(&in_dev->mr_ifc_timer)) 1866 __in_dev_put(in_dev); 1867 in_dev->mr_gq_running = 0; 1868 if (timer_delete(&in_dev->mr_gq_timer)) 1869 __in_dev_put(in_dev); 1870 #endif 1871 1872 ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS); 1873 } 1874 1875 #ifdef CONFIG_IP_MULTICAST 1876 static void ip_mc_reset(struct in_device *in_dev) 1877 { 1878 struct net *net = dev_net(in_dev->dev); 1879 1880 in_dev->mr_qi = IGMP_QUERY_INTERVAL; 1881 in_dev->mr_qri = IGMP_QUERY_RESPONSE_INTERVAL; 1882 in_dev->mr_qrv = READ_ONCE(net->ipv4.sysctl_igmp_qrv); 1883 } 1884 #else 1885 static void ip_mc_reset(struct in_device *in_dev) 1886 { 1887 } 1888 #endif 1889 1890 void ip_mc_init_dev(struct in_device *in_dev) 1891 { 1892 ASSERT_RTNL(); 1893 1894 #ifdef CONFIG_IP_MULTICAST 1895 timer_setup(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 0); 1896 timer_setup(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 0); 1897 #endif 1898 ip_mc_reset(in_dev); 1899 1900 spin_lock_init(&in_dev->mc_tomb_lock); 1901 } 1902 1903 /* Device going up */ 1904 1905 void ip_mc_up(struct in_device *in_dev) 1906 { 1907 struct ip_mc_list *pmc; 1908 1909 ASSERT_RTNL(); 1910 1911 ip_mc_reset(in_dev); 1912 ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS); 1913 1914 for_each_pmc_rtnl(in_dev, pmc) { 1915 #ifdef CONFIG_IP_MULTICAST 1916 igmpv3_del_delrec(in_dev, pmc); 1917 #endif 1918 igmp_group_added(pmc); 1919 } 1920 } 1921 1922 /* 1923 * Device is about to be destroyed: clean up. 1924 */ 1925 1926 void ip_mc_destroy_dev(struct in_device *in_dev) 1927 { 1928 struct ip_mc_list *i; 1929 1930 ASSERT_RTNL(); 1931 1932 /* Deactivate timers */ 1933 ip_mc_down(in_dev); 1934 #ifdef CONFIG_IP_MULTICAST 1935 igmpv3_clear_delrec(in_dev); 1936 #endif 1937 1938 while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) { 1939 ip_mc_hash_remove(in_dev, i); 1940 in_dev->mc_list = i->next_rcu; 1941 WRITE_ONCE(in_dev->mc_count, in_dev->mc_count - 1); 1942 ip_mc_clear_src(i); 1943 ip_ma_put(i); 1944 } 1945 } 1946 1947 /* RTNL is locked */ 1948 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr) 1949 { 1950 struct net_device *dev = NULL; 1951 struct in_device *idev = NULL; 1952 1953 if (imr->imr_ifindex) { 1954 idev = inetdev_by_index(net, imr->imr_ifindex); 1955 return idev; 1956 } 1957 if (imr->imr_address.s_addr) { 1958 dev = __ip_dev_find(net, imr->imr_address.s_addr, false); 1959 if (!dev) 1960 return NULL; 1961 } 1962 1963 if (!dev) { 1964 struct rtable *rt = ip_route_output(net, 1965 imr->imr_multiaddr.s_addr, 1966 0, 0, 0, 1967 RT_SCOPE_UNIVERSE); 1968 if (!IS_ERR(rt)) { 1969 dev = rt->dst.dev; 1970 ip_rt_put(rt); 1971 } 1972 } 1973 if (dev) { 1974 imr->imr_ifindex = dev->ifindex; 1975 idev = __in_dev_get_rtnl(dev); 1976 } 1977 return idev; 1978 } 1979 1980 /* 1981 * Join a socket to a group 1982 */ 1983 1984 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode, 1985 __be32 *psfsrc) 1986 { 1987 struct ip_sf_list *psf, *psf_prev; 1988 int rv = 0; 1989 1990 psf_prev = NULL; 1991 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1992 if (psf->sf_inaddr == *psfsrc) 1993 break; 1994 psf_prev = psf; 1995 } 1996 if (!psf || psf->sf_count[sfmode] == 0) { 1997 /* source filter not found, or count wrong => bug */ 1998 return -ESRCH; 1999 } 2000 psf->sf_count[sfmode]--; 2001 if (psf->sf_count[sfmode] == 0) { 2002 ip_rt_multicast_event(pmc->interface); 2003 } 2004 if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) { 2005 #ifdef CONFIG_IP_MULTICAST 2006 struct in_device *in_dev = pmc->interface; 2007 struct net *net = dev_net(in_dev->dev); 2008 #endif 2009 2010 /* no more filters for this source */ 2011 if (psf_prev) 2012 psf_prev->sf_next = psf->sf_next; 2013 else 2014 pmc->sources = psf->sf_next; 2015 #ifdef CONFIG_IP_MULTICAST 2016 if (psf->sf_oldin && 2017 !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) { 2018 psf->sf_crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); 2019 psf->sf_next = pmc->tomb; 2020 pmc->tomb = psf; 2021 rv = 1; 2022 } else 2023 #endif 2024 kfree(psf); 2025 } 2026 return rv; 2027 } 2028 2029 #ifndef CONFIG_IP_MULTICAST 2030 #define igmp_ifc_event(x) do { } while (0) 2031 #endif 2032 2033 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 2034 int sfcount, __be32 *psfsrc, int delta) 2035 { 2036 struct ip_mc_list *pmc; 2037 int changerec = 0; 2038 int i, err; 2039 2040 if (!in_dev) 2041 return -ENODEV; 2042 rcu_read_lock(); 2043 for_each_pmc_rcu(in_dev, pmc) { 2044 if (*pmca == pmc->multiaddr) 2045 break; 2046 } 2047 if (!pmc) { 2048 /* MCA not found?? bug */ 2049 rcu_read_unlock(); 2050 return -ESRCH; 2051 } 2052 spin_lock_bh(&pmc->lock); 2053 rcu_read_unlock(); 2054 #ifdef CONFIG_IP_MULTICAST 2055 sf_markstate(pmc); 2056 #endif 2057 if (!delta) { 2058 err = -EINVAL; 2059 if (!pmc->sfcount[sfmode]) 2060 goto out_unlock; 2061 pmc->sfcount[sfmode]--; 2062 } 2063 err = 0; 2064 for (i = 0; i < sfcount; i++) { 2065 int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]); 2066 2067 changerec |= rv > 0; 2068 if (!err && rv < 0) 2069 err = rv; 2070 } 2071 if (pmc->sfmode == MCAST_EXCLUDE && 2072 pmc->sfcount[MCAST_EXCLUDE] == 0 && 2073 pmc->sfcount[MCAST_INCLUDE]) { 2074 #ifdef CONFIG_IP_MULTICAST 2075 struct ip_sf_list *psf; 2076 struct net *net = dev_net(in_dev->dev); 2077 #endif 2078 2079 /* filter mode change */ 2080 pmc->sfmode = MCAST_INCLUDE; 2081 #ifdef CONFIG_IP_MULTICAST 2082 pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); 2083 WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount); 2084 for (psf = pmc->sources; psf; psf = psf->sf_next) 2085 psf->sf_crcount = 0; 2086 igmp_ifc_event(pmc->interface); 2087 } else if (sf_setstate(pmc) || changerec) { 2088 igmp_ifc_event(pmc->interface); 2089 #endif 2090 } 2091 out_unlock: 2092 spin_unlock_bh(&pmc->lock); 2093 return err; 2094 } 2095 2096 /* 2097 * Add multicast single-source filter to the interface list 2098 */ 2099 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode, 2100 __be32 *psfsrc) 2101 { 2102 struct ip_sf_list *psf, *psf_prev; 2103 2104 psf_prev = NULL; 2105 for (psf = pmc->sources; psf; psf = psf->sf_next) { 2106 if (psf->sf_inaddr == *psfsrc) 2107 break; 2108 psf_prev = psf; 2109 } 2110 if (!psf) { 2111 psf = kzalloc_obj(*psf, GFP_ATOMIC); 2112 if (!psf) 2113 return -ENOBUFS; 2114 psf->sf_inaddr = *psfsrc; 2115 if (psf_prev) { 2116 psf_prev->sf_next = psf; 2117 } else 2118 pmc->sources = psf; 2119 } 2120 psf->sf_count[sfmode]++; 2121 if (psf->sf_count[sfmode] == 1) { 2122 ip_rt_multicast_event(pmc->interface); 2123 } 2124 return 0; 2125 } 2126 2127 #ifdef CONFIG_IP_MULTICAST 2128 static void sf_markstate(struct ip_mc_list *pmc) 2129 { 2130 struct ip_sf_list *psf; 2131 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; 2132 2133 for (psf = pmc->sources; psf; psf = psf->sf_next) 2134 if (pmc->sfcount[MCAST_EXCLUDE]) { 2135 psf->sf_oldin = mca_xcount == 2136 psf->sf_count[MCAST_EXCLUDE] && 2137 !psf->sf_count[MCAST_INCLUDE]; 2138 } else 2139 psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0; 2140 } 2141 2142 static int sf_setstate(struct ip_mc_list *pmc) 2143 { 2144 struct ip_sf_list *psf, *dpsf; 2145 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; 2146 int qrv = pmc->interface->mr_qrv; 2147 int new_in, rv; 2148 2149 rv = 0; 2150 for (psf = pmc->sources; psf; psf = psf->sf_next) { 2151 if (pmc->sfcount[MCAST_EXCLUDE]) { 2152 new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] && 2153 !psf->sf_count[MCAST_INCLUDE]; 2154 } else 2155 new_in = psf->sf_count[MCAST_INCLUDE] != 0; 2156 if (new_in) { 2157 if (!psf->sf_oldin) { 2158 struct ip_sf_list *prev = NULL; 2159 2160 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) { 2161 if (dpsf->sf_inaddr == psf->sf_inaddr) 2162 break; 2163 prev = dpsf; 2164 } 2165 if (dpsf) { 2166 if (prev) 2167 prev->sf_next = dpsf->sf_next; 2168 else 2169 pmc->tomb = dpsf->sf_next; 2170 kfree(dpsf); 2171 } 2172 psf->sf_crcount = qrv; 2173 rv++; 2174 } 2175 } else if (psf->sf_oldin) { 2176 2177 psf->sf_crcount = 0; 2178 /* 2179 * add or update "delete" records if an active filter 2180 * is now inactive 2181 */ 2182 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) 2183 if (dpsf->sf_inaddr == psf->sf_inaddr) 2184 break; 2185 if (!dpsf) { 2186 dpsf = kmalloc_obj(*dpsf, GFP_ATOMIC); 2187 if (!dpsf) 2188 continue; 2189 *dpsf = *psf; 2190 /* pmc->lock held by callers */ 2191 dpsf->sf_next = pmc->tomb; 2192 pmc->tomb = dpsf; 2193 } 2194 dpsf->sf_crcount = qrv; 2195 rv++; 2196 } 2197 } 2198 return rv; 2199 } 2200 #endif 2201 2202 /* 2203 * Add multicast source filter list to the interface list 2204 */ 2205 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 2206 int sfcount, __be32 *psfsrc, int delta) 2207 { 2208 struct ip_mc_list *pmc; 2209 int isexclude; 2210 int i, err; 2211 2212 if (!in_dev) 2213 return -ENODEV; 2214 rcu_read_lock(); 2215 for_each_pmc_rcu(in_dev, pmc) { 2216 if (*pmca == pmc->multiaddr) 2217 break; 2218 } 2219 if (!pmc) { 2220 /* MCA not found?? bug */ 2221 rcu_read_unlock(); 2222 return -ESRCH; 2223 } 2224 spin_lock_bh(&pmc->lock); 2225 rcu_read_unlock(); 2226 2227 #ifdef CONFIG_IP_MULTICAST 2228 sf_markstate(pmc); 2229 #endif 2230 isexclude = pmc->sfmode == MCAST_EXCLUDE; 2231 if (!delta) 2232 pmc->sfcount[sfmode]++; 2233 err = 0; 2234 for (i = 0; i < sfcount; i++) { 2235 err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]); 2236 if (err) 2237 break; 2238 } 2239 if (err) { 2240 int j; 2241 2242 if (!delta) 2243 pmc->sfcount[sfmode]--; 2244 for (j = 0; j < i; j++) 2245 (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]); 2246 } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) { 2247 #ifdef CONFIG_IP_MULTICAST 2248 struct ip_sf_list *psf; 2249 struct net *net = dev_net(pmc->interface->dev); 2250 in_dev = pmc->interface; 2251 #endif 2252 2253 /* filter mode change */ 2254 if (pmc->sfcount[MCAST_EXCLUDE]) 2255 pmc->sfmode = MCAST_EXCLUDE; 2256 else if (pmc->sfcount[MCAST_INCLUDE]) 2257 pmc->sfmode = MCAST_INCLUDE; 2258 #ifdef CONFIG_IP_MULTICAST 2259 /* else no filters; keep old mode for reports */ 2260 2261 pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); 2262 WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount); 2263 for (psf = pmc->sources; psf; psf = psf->sf_next) 2264 psf->sf_crcount = 0; 2265 igmp_ifc_event(in_dev); 2266 } else if (sf_setstate(pmc)) { 2267 igmp_ifc_event(in_dev); 2268 #endif 2269 } 2270 spin_unlock_bh(&pmc->lock); 2271 return err; 2272 } 2273 2274 static void ip_mc_clear_src(struct ip_mc_list *pmc) 2275 { 2276 struct ip_sf_list *tomb, *sources; 2277 2278 spin_lock_bh(&pmc->lock); 2279 tomb = pmc->tomb; 2280 pmc->tomb = NULL; 2281 sources = pmc->sources; 2282 pmc->sources = NULL; 2283 pmc->sfmode = MCAST_EXCLUDE; 2284 pmc->sfcount[MCAST_INCLUDE] = 0; 2285 pmc->sfcount[MCAST_EXCLUDE] = 1; 2286 spin_unlock_bh(&pmc->lock); 2287 2288 ip_sf_list_clear_all(tomb); 2289 ip_sf_list_clear_all(sources); 2290 } 2291 2292 /* Join a multicast group 2293 */ 2294 static int __ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr, 2295 unsigned int mode) 2296 { 2297 __be32 addr = imr->imr_multiaddr.s_addr; 2298 struct ip_mc_socklist *iml, *i; 2299 struct in_device *in_dev; 2300 struct inet_sock *inet = inet_sk(sk); 2301 struct net *net = sock_net(sk); 2302 int ifindex; 2303 int count = 0; 2304 int err; 2305 2306 ASSERT_RTNL(); 2307 2308 if (!ipv4_is_multicast(addr)) 2309 return -EINVAL; 2310 2311 in_dev = ip_mc_find_dev(net, imr); 2312 2313 if (!in_dev) { 2314 err = -ENODEV; 2315 goto done; 2316 } 2317 2318 err = -EADDRINUSE; 2319 ifindex = imr->imr_ifindex; 2320 for_each_pmc_rtnl(inet, i) { 2321 if (i->multi.imr_multiaddr.s_addr == addr && 2322 i->multi.imr_ifindex == ifindex) 2323 goto done; 2324 count++; 2325 } 2326 err = -ENOBUFS; 2327 if (count >= READ_ONCE(net->ipv4.sysctl_igmp_max_memberships)) 2328 goto done; 2329 iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL); 2330 if (!iml) 2331 goto done; 2332 2333 memcpy(&iml->multi, imr, sizeof(*imr)); 2334 iml->next_rcu = inet->mc_list; 2335 iml->sflist = NULL; 2336 iml->sfmode = mode; 2337 rcu_assign_pointer(inet->mc_list, iml); 2338 ____ip_mc_inc_group(in_dev, addr, mode, GFP_KERNEL); 2339 err = 0; 2340 done: 2341 return err; 2342 } 2343 2344 /* Join ASM (Any-Source Multicast) group 2345 */ 2346 int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr) 2347 { 2348 return __ip_mc_join_group(sk, imr, MCAST_EXCLUDE); 2349 } 2350 EXPORT_SYMBOL(ip_mc_join_group); 2351 2352 /* Join SSM (Source-Specific Multicast) group 2353 */ 2354 int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr, 2355 unsigned int mode) 2356 { 2357 return __ip_mc_join_group(sk, imr, mode); 2358 } 2359 2360 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml, 2361 struct in_device *in_dev) 2362 { 2363 struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist); 2364 int err; 2365 2366 if (!psf) { 2367 /* any-source empty exclude case */ 2368 return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, 2369 iml->sfmode, 0, NULL, 0); 2370 } 2371 err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, 2372 iml->sfmode, psf->sl_count, psf->sl_addr, 0); 2373 RCU_INIT_POINTER(iml->sflist, NULL); 2374 /* decrease mem now to avoid the memleak warning */ 2375 atomic_sub(struct_size(psf, sl_addr, psf->sl_max), &sk->sk_omem_alloc); 2376 kfree_rcu(psf, rcu); 2377 return err; 2378 } 2379 2380 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr) 2381 { 2382 struct inet_sock *inet = inet_sk(sk); 2383 struct ip_mc_socklist *iml; 2384 struct ip_mc_socklist __rcu **imlp; 2385 struct in_device *in_dev; 2386 struct net *net = sock_net(sk); 2387 __be32 group = imr->imr_multiaddr.s_addr; 2388 u32 ifindex; 2389 int ret = -EADDRNOTAVAIL; 2390 2391 ASSERT_RTNL(); 2392 2393 in_dev = ip_mc_find_dev(net, imr); 2394 if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) { 2395 ret = -ENODEV; 2396 goto out; 2397 } 2398 ifindex = imr->imr_ifindex; 2399 for (imlp = &inet->mc_list; 2400 (iml = rtnl_dereference(*imlp)) != NULL; 2401 imlp = &iml->next_rcu) { 2402 if (iml->multi.imr_multiaddr.s_addr != group) 2403 continue; 2404 if (ifindex) { 2405 if (iml->multi.imr_ifindex != ifindex) 2406 continue; 2407 } else if (imr->imr_address.s_addr && imr->imr_address.s_addr != 2408 iml->multi.imr_address.s_addr) 2409 continue; 2410 2411 (void) ip_mc_leave_src(sk, iml, in_dev); 2412 2413 *imlp = iml->next_rcu; 2414 2415 if (in_dev) 2416 ip_mc_dec_group(in_dev, group); 2417 2418 /* decrease mem now to avoid the memleak warning */ 2419 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); 2420 kfree_rcu(iml, rcu); 2421 return 0; 2422 } 2423 out: 2424 return ret; 2425 } 2426 EXPORT_SYMBOL(ip_mc_leave_group); 2427 2428 int ip_mc_source(int add, int omode, struct sock *sk, struct 2429 ip_mreq_source *mreqs, int ifindex) 2430 { 2431 int err; 2432 struct ip_mreqn imr; 2433 __be32 addr = mreqs->imr_multiaddr; 2434 struct ip_mc_socklist *pmc; 2435 struct in_device *in_dev = NULL; 2436 struct inet_sock *inet = inet_sk(sk); 2437 struct ip_sf_socklist *psl; 2438 struct net *net = sock_net(sk); 2439 int leavegroup = 0; 2440 int i, j, rv; 2441 2442 if (!ipv4_is_multicast(addr)) 2443 return -EINVAL; 2444 2445 ASSERT_RTNL(); 2446 2447 imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr; 2448 imr.imr_address.s_addr = mreqs->imr_interface; 2449 imr.imr_ifindex = ifindex; 2450 in_dev = ip_mc_find_dev(net, &imr); 2451 2452 if (!in_dev) { 2453 err = -ENODEV; 2454 goto done; 2455 } 2456 err = -EADDRNOTAVAIL; 2457 2458 for_each_pmc_rtnl(inet, pmc) { 2459 if ((pmc->multi.imr_multiaddr.s_addr == 2460 imr.imr_multiaddr.s_addr) && 2461 (pmc->multi.imr_ifindex == imr.imr_ifindex)) 2462 break; 2463 } 2464 if (!pmc) { /* must have a prior join */ 2465 err = -EINVAL; 2466 goto done; 2467 } 2468 /* if a source filter was set, must be the same mode as before */ 2469 if (pmc->sflist) { 2470 if (pmc->sfmode != omode) { 2471 err = -EINVAL; 2472 goto done; 2473 } 2474 } else if (pmc->sfmode != omode) { 2475 /* allow mode switches for empty-set filters */ 2476 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0); 2477 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0, 2478 NULL, 0); 2479 pmc->sfmode = omode; 2480 } 2481 2482 psl = rtnl_dereference(pmc->sflist); 2483 if (!add) { 2484 if (!psl) 2485 goto done; /* err = -EADDRNOTAVAIL */ 2486 rv = !0; 2487 for (i = 0; i < psl->sl_count; i++) { 2488 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr, 2489 sizeof(__be32)); 2490 if (rv == 0) 2491 break; 2492 } 2493 if (rv) /* source not found */ 2494 goto done; /* err = -EADDRNOTAVAIL */ 2495 2496 /* special case - (INCLUDE, empty) == LEAVE_GROUP */ 2497 if (psl->sl_count == 1 && omode == MCAST_INCLUDE) { 2498 leavegroup = 1; 2499 goto done; 2500 } 2501 2502 /* update the interface filter */ 2503 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1, 2504 &mreqs->imr_sourceaddr, 1); 2505 2506 for (j = i+1; j < psl->sl_count; j++) 2507 psl->sl_addr[j-1] = psl->sl_addr[j]; 2508 psl->sl_count--; 2509 err = 0; 2510 goto done; 2511 } 2512 /* else, add a new source to the filter */ 2513 2514 if (psl && psl->sl_count >= READ_ONCE(net->ipv4.sysctl_igmp_max_msf)) { 2515 err = -ENOBUFS; 2516 goto done; 2517 } 2518 if (!psl || psl->sl_count == psl->sl_max) { 2519 struct ip_sf_socklist *newpsl; 2520 int count = IP_SFBLOCK; 2521 2522 if (psl) 2523 count += psl->sl_max; 2524 newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr, count), 2525 GFP_KERNEL); 2526 if (!newpsl) { 2527 err = -ENOBUFS; 2528 goto done; 2529 } 2530 newpsl->sl_max = count; 2531 newpsl->sl_count = count - IP_SFBLOCK; 2532 if (psl) { 2533 for (i = 0; i < psl->sl_count; i++) 2534 newpsl->sl_addr[i] = psl->sl_addr[i]; 2535 /* decrease mem now to avoid the memleak warning */ 2536 atomic_sub(struct_size(psl, sl_addr, psl->sl_max), 2537 &sk->sk_omem_alloc); 2538 } 2539 rcu_assign_pointer(pmc->sflist, newpsl); 2540 if (psl) 2541 kfree_rcu(psl, rcu); 2542 psl = newpsl; 2543 } 2544 rv = 1; /* > 0 for insert logic below if sl_count is 0 */ 2545 for (i = 0; i < psl->sl_count; i++) { 2546 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr, 2547 sizeof(__be32)); 2548 if (rv == 0) 2549 break; 2550 } 2551 if (rv == 0) /* address already there is an error */ 2552 goto done; 2553 for (j = psl->sl_count-1; j >= i; j--) 2554 psl->sl_addr[j+1] = psl->sl_addr[j]; 2555 psl->sl_addr[i] = mreqs->imr_sourceaddr; 2556 psl->sl_count++; 2557 err = 0; 2558 /* update the interface list */ 2559 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1, 2560 &mreqs->imr_sourceaddr, 1); 2561 done: 2562 if (leavegroup) 2563 err = ip_mc_leave_group(sk, &imr); 2564 return err; 2565 } 2566 2567 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex) 2568 { 2569 int err = 0; 2570 struct ip_mreqn imr; 2571 __be32 addr = msf->imsf_multiaddr; 2572 struct ip_mc_socklist *pmc; 2573 struct in_device *in_dev; 2574 struct inet_sock *inet = inet_sk(sk); 2575 struct ip_sf_socklist *newpsl, *psl; 2576 struct net *net = sock_net(sk); 2577 int leavegroup = 0; 2578 2579 if (!ipv4_is_multicast(addr)) 2580 return -EINVAL; 2581 if (msf->imsf_fmode != MCAST_INCLUDE && 2582 msf->imsf_fmode != MCAST_EXCLUDE) 2583 return -EINVAL; 2584 2585 ASSERT_RTNL(); 2586 2587 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; 2588 imr.imr_address.s_addr = msf->imsf_interface; 2589 imr.imr_ifindex = ifindex; 2590 in_dev = ip_mc_find_dev(net, &imr); 2591 2592 if (!in_dev) { 2593 err = -ENODEV; 2594 goto done; 2595 } 2596 2597 /* special case - (INCLUDE, empty) == LEAVE_GROUP */ 2598 if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) { 2599 leavegroup = 1; 2600 goto done; 2601 } 2602 2603 for_each_pmc_rtnl(inet, pmc) { 2604 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && 2605 pmc->multi.imr_ifindex == imr.imr_ifindex) 2606 break; 2607 } 2608 if (!pmc) { /* must have a prior join */ 2609 err = -EINVAL; 2610 goto done; 2611 } 2612 if (msf->imsf_numsrc) { 2613 newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr, 2614 msf->imsf_numsrc), 2615 GFP_KERNEL); 2616 if (!newpsl) { 2617 err = -ENOBUFS; 2618 goto done; 2619 } 2620 newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc; 2621 memcpy(newpsl->sl_addr, msf->imsf_slist_flex, 2622 flex_array_size(msf, imsf_slist_flex, msf->imsf_numsrc)); 2623 err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr, 2624 msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0); 2625 if (err) { 2626 sock_kfree_s(sk, newpsl, 2627 struct_size(newpsl, sl_addr, 2628 newpsl->sl_max)); 2629 goto done; 2630 } 2631 } else { 2632 newpsl = NULL; 2633 (void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr, 2634 msf->imsf_fmode, 0, NULL, 0); 2635 } 2636 psl = rtnl_dereference(pmc->sflist); 2637 if (psl) { 2638 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, 2639 psl->sl_count, psl->sl_addr, 0); 2640 /* decrease mem now to avoid the memleak warning */ 2641 atomic_sub(struct_size(psl, sl_addr, psl->sl_max), 2642 &sk->sk_omem_alloc); 2643 } else { 2644 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, 2645 0, NULL, 0); 2646 } 2647 rcu_assign_pointer(pmc->sflist, newpsl); 2648 if (psl) 2649 kfree_rcu(psl, rcu); 2650 pmc->sfmode = msf->imsf_fmode; 2651 err = 0; 2652 done: 2653 if (leavegroup) 2654 err = ip_mc_leave_group(sk, &imr); 2655 return err; 2656 } 2657 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf, 2658 sockptr_t optval, sockptr_t optlen) 2659 { 2660 int err, len, count, copycount, msf_size; 2661 struct ip_mreqn imr; 2662 __be32 addr = msf->imsf_multiaddr; 2663 struct ip_mc_socklist *pmc; 2664 struct in_device *in_dev; 2665 struct inet_sock *inet = inet_sk(sk); 2666 struct ip_sf_socklist *psl; 2667 struct net *net = sock_net(sk); 2668 2669 ASSERT_RTNL(); 2670 2671 if (!ipv4_is_multicast(addr)) 2672 return -EINVAL; 2673 2674 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; 2675 imr.imr_address.s_addr = msf->imsf_interface; 2676 imr.imr_ifindex = 0; 2677 in_dev = ip_mc_find_dev(net, &imr); 2678 2679 if (!in_dev) { 2680 err = -ENODEV; 2681 goto done; 2682 } 2683 err = -EADDRNOTAVAIL; 2684 2685 for_each_pmc_rtnl(inet, pmc) { 2686 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && 2687 pmc->multi.imr_ifindex == imr.imr_ifindex) 2688 break; 2689 } 2690 if (!pmc) /* must have a prior join */ 2691 goto done; 2692 msf->imsf_fmode = pmc->sfmode; 2693 psl = rtnl_dereference(pmc->sflist); 2694 if (!psl) { 2695 count = 0; 2696 } else { 2697 count = psl->sl_count; 2698 } 2699 copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc; 2700 len = flex_array_size(psl, sl_addr, copycount); 2701 msf->imsf_numsrc = count; 2702 msf_size = IP_MSFILTER_SIZE(copycount); 2703 if (copy_to_sockptr(optlen, &msf_size, sizeof(int)) || 2704 copy_to_sockptr(optval, msf, IP_MSFILTER_SIZE(0))) { 2705 return -EFAULT; 2706 } 2707 if (len && 2708 copy_to_sockptr_offset(optval, 2709 offsetof(struct ip_msfilter, imsf_slist_flex), 2710 psl->sl_addr, len)) 2711 return -EFAULT; 2712 return 0; 2713 done: 2714 return err; 2715 } 2716 2717 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf, 2718 sockptr_t optval, size_t ss_offset) 2719 { 2720 int i, count, copycount; 2721 struct sockaddr_in *psin; 2722 __be32 addr; 2723 struct ip_mc_socklist *pmc; 2724 struct inet_sock *inet = inet_sk(sk); 2725 struct ip_sf_socklist *psl; 2726 2727 ASSERT_RTNL(); 2728 2729 psin = (struct sockaddr_in *)&gsf->gf_group; 2730 if (psin->sin_family != AF_INET) 2731 return -EINVAL; 2732 addr = psin->sin_addr.s_addr; 2733 if (!ipv4_is_multicast(addr)) 2734 return -EINVAL; 2735 2736 for_each_pmc_rtnl(inet, pmc) { 2737 if (pmc->multi.imr_multiaddr.s_addr == addr && 2738 pmc->multi.imr_ifindex == gsf->gf_interface) 2739 break; 2740 } 2741 if (!pmc) /* must have a prior join */ 2742 return -EADDRNOTAVAIL; 2743 gsf->gf_fmode = pmc->sfmode; 2744 psl = rtnl_dereference(pmc->sflist); 2745 count = psl ? psl->sl_count : 0; 2746 copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc; 2747 gsf->gf_numsrc = count; 2748 for (i = 0; i < copycount; i++) { 2749 struct sockaddr_storage ss; 2750 2751 psin = (struct sockaddr_in *)&ss; 2752 memset(&ss, 0, sizeof(ss)); 2753 psin->sin_family = AF_INET; 2754 psin->sin_addr.s_addr = psl->sl_addr[i]; 2755 if (copy_to_sockptr_offset(optval, ss_offset, 2756 &ss, sizeof(ss))) 2757 return -EFAULT; 2758 ss_offset += sizeof(ss); 2759 } 2760 return 0; 2761 } 2762 2763 /* 2764 * check if a multicast source filter allows delivery for a given <src,dst,intf> 2765 */ 2766 int ip_mc_sf_allow(const struct sock *sk, __be32 loc_addr, __be32 rmt_addr, 2767 int dif, int sdif) 2768 { 2769 const struct inet_sock *inet = inet_sk(sk); 2770 struct ip_mc_socklist *pmc; 2771 struct ip_sf_socklist *psl; 2772 int i; 2773 int ret; 2774 2775 ret = 1; 2776 if (!ipv4_is_multicast(loc_addr)) 2777 goto out; 2778 2779 rcu_read_lock(); 2780 for_each_pmc_rcu(inet, pmc) { 2781 if (pmc->multi.imr_multiaddr.s_addr == loc_addr && 2782 (pmc->multi.imr_ifindex == dif || 2783 (sdif && pmc->multi.imr_ifindex == sdif))) 2784 break; 2785 } 2786 ret = inet_test_bit(MC_ALL, sk); 2787 if (!pmc) 2788 goto unlock; 2789 psl = rcu_dereference(pmc->sflist); 2790 ret = (pmc->sfmode == MCAST_EXCLUDE); 2791 if (!psl) 2792 goto unlock; 2793 2794 for (i = 0; i < psl->sl_count; i++) { 2795 if (psl->sl_addr[i] == rmt_addr) 2796 break; 2797 } 2798 ret = 0; 2799 if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count) 2800 goto unlock; 2801 if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count) 2802 goto unlock; 2803 ret = 1; 2804 unlock: 2805 rcu_read_unlock(); 2806 out: 2807 return ret; 2808 } 2809 2810 /* 2811 * A socket is closing. 2812 */ 2813 2814 void ip_mc_drop_socket(struct sock *sk) 2815 { 2816 struct inet_sock *inet = inet_sk(sk); 2817 struct ip_mc_socklist *iml; 2818 struct net *net = sock_net(sk); 2819 2820 if (!inet->mc_list) 2821 return; 2822 2823 rtnl_lock(); 2824 while ((iml = rtnl_dereference(inet->mc_list)) != NULL) { 2825 struct in_device *in_dev; 2826 2827 inet->mc_list = iml->next_rcu; 2828 in_dev = inetdev_by_index(net, iml->multi.imr_ifindex); 2829 (void) ip_mc_leave_src(sk, iml, in_dev); 2830 if (in_dev) 2831 ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr); 2832 /* decrease mem now to avoid the memleak warning */ 2833 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); 2834 kfree_rcu(iml, rcu); 2835 } 2836 rtnl_unlock(); 2837 } 2838 2839 /* called with rcu_read_lock() */ 2840 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto) 2841 { 2842 struct ip_mc_list *im; 2843 struct ip_mc_list __rcu **mc_hash; 2844 struct ip_sf_list *psf; 2845 int rv = 0; 2846 2847 mc_hash = rcu_dereference(in_dev->mc_hash); 2848 if (mc_hash) { 2849 u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG); 2850 2851 for (im = rcu_dereference(mc_hash[hash]); 2852 im != NULL; 2853 im = rcu_dereference(im->next_hash)) { 2854 if (im->multiaddr == mc_addr) 2855 break; 2856 } 2857 } else { 2858 for_each_pmc_rcu(in_dev, im) { 2859 if (im->multiaddr == mc_addr) 2860 break; 2861 } 2862 } 2863 if (im && proto == IPPROTO_IGMP) { 2864 rv = 1; 2865 } else if (im) { 2866 if (src_addr) { 2867 spin_lock_bh(&im->lock); 2868 for (psf = im->sources; psf; psf = psf->sf_next) { 2869 if (psf->sf_inaddr == src_addr) 2870 break; 2871 } 2872 if (psf) 2873 rv = psf->sf_count[MCAST_INCLUDE] || 2874 psf->sf_count[MCAST_EXCLUDE] != 2875 im->sfcount[MCAST_EXCLUDE]; 2876 else 2877 rv = im->sfcount[MCAST_EXCLUDE] != 0; 2878 spin_unlock_bh(&im->lock); 2879 } else 2880 rv = 1; /* unspecified source; tentatively allow */ 2881 } 2882 return rv; 2883 } 2884 2885 #if defined(CONFIG_PROC_FS) 2886 struct igmp_mc_iter_state { 2887 struct seq_net_private p; 2888 struct net_device *dev; 2889 struct in_device *in_dev; 2890 }; 2891 2892 #define igmp_mc_seq_private(seq) ((struct igmp_mc_iter_state *)(seq)->private) 2893 2894 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq) 2895 { 2896 struct net *net = seq_file_net(seq); 2897 struct ip_mc_list *im = NULL; 2898 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2899 2900 state->in_dev = NULL; 2901 for_each_netdev_rcu(net, state->dev) { 2902 struct in_device *in_dev; 2903 2904 in_dev = __in_dev_get_rcu(state->dev); 2905 if (!in_dev) 2906 continue; 2907 im = rcu_dereference(in_dev->mc_list); 2908 if (im) { 2909 state->in_dev = in_dev; 2910 break; 2911 } 2912 } 2913 return im; 2914 } 2915 2916 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im) 2917 { 2918 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2919 2920 im = rcu_dereference(im->next_rcu); 2921 while (!im) { 2922 state->dev = next_net_device_rcu(state->dev); 2923 if (!state->dev) { 2924 state->in_dev = NULL; 2925 break; 2926 } 2927 state->in_dev = __in_dev_get_rcu(state->dev); 2928 if (!state->in_dev) 2929 continue; 2930 im = rcu_dereference(state->in_dev->mc_list); 2931 } 2932 return im; 2933 } 2934 2935 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos) 2936 { 2937 struct ip_mc_list *im = igmp_mc_get_first(seq); 2938 if (im) 2939 while (pos && (im = igmp_mc_get_next(seq, im)) != NULL) 2940 --pos; 2941 return pos ? NULL : im; 2942 } 2943 2944 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos) 2945 __acquires(rcu) 2946 { 2947 rcu_read_lock(); 2948 return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 2949 } 2950 2951 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2952 { 2953 struct ip_mc_list *im; 2954 if (v == SEQ_START_TOKEN) 2955 im = igmp_mc_get_first(seq); 2956 else 2957 im = igmp_mc_get_next(seq, v); 2958 ++*pos; 2959 return im; 2960 } 2961 2962 static void igmp_mc_seq_stop(struct seq_file *seq, void *v) 2963 __releases(rcu) 2964 { 2965 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2966 2967 state->in_dev = NULL; 2968 state->dev = NULL; 2969 rcu_read_unlock(); 2970 } 2971 2972 static int igmp_mc_seq_show(struct seq_file *seq, void *v) 2973 { 2974 if (v == SEQ_START_TOKEN) 2975 seq_puts(seq, 2976 "Idx\tDevice : Count Querier\tGroup Users Timer\tReporter\n"); 2977 else { 2978 struct ip_mc_list *im = v; 2979 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2980 char *querier; 2981 int tm_running; 2982 long delta; 2983 2984 #ifdef CONFIG_IP_MULTICAST 2985 querier = IGMP_V1_SEEN(state->in_dev) ? "V1" : 2986 IGMP_V2_SEEN(state->in_dev) ? "V2" : 2987 "V3"; 2988 #else 2989 querier = "NONE"; 2990 #endif 2991 2992 if (rcu_access_pointer(state->in_dev->mc_list) == im) { 2993 seq_printf(seq, "%d\t%-10s: %5d %7s\n", 2994 state->dev->ifindex, state->dev->name, 2995 READ_ONCE(state->in_dev->mc_count), 2996 querier); 2997 } 2998 2999 tm_running = READ_ONCE(im->tm_running); 3000 delta = READ_ONCE(im->timer.expires) - jiffies; 3001 seq_printf(seq, 3002 "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n", 3003 im->multiaddr, READ_ONCE(im->users), 3004 tm_running, 3005 tm_running ? jiffies_delta_to_clock_t(delta) : 0, 3006 READ_ONCE(im->reporter)); 3007 } 3008 return 0; 3009 } 3010 3011 static const struct seq_operations igmp_mc_seq_ops = { 3012 .start = igmp_mc_seq_start, 3013 .next = igmp_mc_seq_next, 3014 .stop = igmp_mc_seq_stop, 3015 .show = igmp_mc_seq_show, 3016 }; 3017 3018 struct igmp_mcf_iter_state { 3019 struct seq_net_private p; 3020 struct net_device *dev; 3021 struct in_device *idev; 3022 struct ip_mc_list *im; 3023 }; 3024 3025 #define igmp_mcf_seq_private(seq) ((struct igmp_mcf_iter_state *)(seq)->private) 3026 3027 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq) 3028 { 3029 struct net *net = seq_file_net(seq); 3030 struct ip_sf_list *psf = NULL; 3031 struct ip_mc_list *im = NULL; 3032 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 3033 3034 state->idev = NULL; 3035 state->im = NULL; 3036 for_each_netdev_rcu(net, state->dev) { 3037 struct in_device *idev; 3038 idev = __in_dev_get_rcu(state->dev); 3039 if (unlikely(!idev)) 3040 continue; 3041 im = rcu_dereference(idev->mc_list); 3042 if (likely(im)) { 3043 spin_lock_bh(&im->lock); 3044 psf = im->sources; 3045 if (likely(psf)) { 3046 state->im = im; 3047 state->idev = idev; 3048 break; 3049 } 3050 spin_unlock_bh(&im->lock); 3051 } 3052 } 3053 return psf; 3054 } 3055 3056 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf) 3057 { 3058 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 3059 3060 psf = psf->sf_next; 3061 while (!psf) { 3062 spin_unlock_bh(&state->im->lock); 3063 state->im = state->im->next; 3064 while (!state->im) { 3065 state->dev = next_net_device_rcu(state->dev); 3066 if (!state->dev) { 3067 state->idev = NULL; 3068 goto out; 3069 } 3070 state->idev = __in_dev_get_rcu(state->dev); 3071 if (!state->idev) 3072 continue; 3073 state->im = rcu_dereference(state->idev->mc_list); 3074 } 3075 spin_lock_bh(&state->im->lock); 3076 psf = state->im->sources; 3077 } 3078 out: 3079 return psf; 3080 } 3081 3082 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos) 3083 { 3084 struct ip_sf_list *psf = igmp_mcf_get_first(seq); 3085 if (psf) 3086 while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL) 3087 --pos; 3088 return pos ? NULL : psf; 3089 } 3090 3091 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos) 3092 __acquires(rcu) 3093 { 3094 rcu_read_lock(); 3095 return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 3096 } 3097 3098 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos) 3099 { 3100 struct ip_sf_list *psf; 3101 if (v == SEQ_START_TOKEN) 3102 psf = igmp_mcf_get_first(seq); 3103 else 3104 psf = igmp_mcf_get_next(seq, v); 3105 ++*pos; 3106 return psf; 3107 } 3108 3109 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v) 3110 __releases(rcu) 3111 { 3112 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 3113 if (likely(state->im)) { 3114 spin_unlock_bh(&state->im->lock); 3115 state->im = NULL; 3116 } 3117 state->idev = NULL; 3118 state->dev = NULL; 3119 rcu_read_unlock(); 3120 } 3121 3122 static int igmp_mcf_seq_show(struct seq_file *seq, void *v) 3123 { 3124 struct ip_sf_list *psf = v; 3125 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 3126 3127 if (v == SEQ_START_TOKEN) { 3128 seq_puts(seq, "Idx Device MCA SRC INC EXC\n"); 3129 } else { 3130 seq_printf(seq, 3131 "%3d %6.6s 0x%08x " 3132 "0x%08x %6lu %6lu\n", 3133 state->dev->ifindex, state->dev->name, 3134 ntohl(state->im->multiaddr), 3135 ntohl(psf->sf_inaddr), 3136 psf->sf_count[MCAST_INCLUDE], 3137 psf->sf_count[MCAST_EXCLUDE]); 3138 } 3139 return 0; 3140 } 3141 3142 static const struct seq_operations igmp_mcf_seq_ops = { 3143 .start = igmp_mcf_seq_start, 3144 .next = igmp_mcf_seq_next, 3145 .stop = igmp_mcf_seq_stop, 3146 .show = igmp_mcf_seq_show, 3147 }; 3148 3149 static int __net_init igmp_net_init(struct net *net) 3150 { 3151 struct proc_dir_entry *pde; 3152 int err; 3153 3154 pde = proc_create_net("igmp", 0444, net->proc_net, &igmp_mc_seq_ops, 3155 sizeof(struct igmp_mc_iter_state)); 3156 if (!pde) 3157 goto out_igmp; 3158 pde = proc_create_net("mcfilter", 0444, net->proc_net, 3159 &igmp_mcf_seq_ops, sizeof(struct igmp_mcf_iter_state)); 3160 if (!pde) 3161 goto out_mcfilter; 3162 err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET, 3163 SOCK_DGRAM, 0, net); 3164 if (err < 0) { 3165 pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n", 3166 err); 3167 goto out_sock; 3168 } 3169 3170 return 0; 3171 3172 out_sock: 3173 remove_proc_entry("mcfilter", net->proc_net); 3174 out_mcfilter: 3175 remove_proc_entry("igmp", net->proc_net); 3176 out_igmp: 3177 return -ENOMEM; 3178 } 3179 3180 static void __net_exit igmp_net_exit(struct net *net) 3181 { 3182 remove_proc_entry("mcfilter", net->proc_net); 3183 remove_proc_entry("igmp", net->proc_net); 3184 inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk); 3185 } 3186 3187 static struct pernet_operations igmp_net_ops = { 3188 .init = igmp_net_init, 3189 .exit = igmp_net_exit, 3190 }; 3191 #endif 3192 3193 static int igmp_netdev_event(struct notifier_block *this, 3194 unsigned long event, void *ptr) 3195 { 3196 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 3197 struct in_device *in_dev; 3198 3199 switch (event) { 3200 case NETDEV_RESEND_IGMP: 3201 in_dev = __in_dev_get_rtnl(dev); 3202 if (in_dev) 3203 ip_mc_rejoin_groups(in_dev); 3204 break; 3205 default: 3206 break; 3207 } 3208 return NOTIFY_DONE; 3209 } 3210 3211 static struct notifier_block igmp_notifier = { 3212 .notifier_call = igmp_netdev_event, 3213 }; 3214 3215 int __init igmp_mc_init(void) 3216 { 3217 #if defined(CONFIG_PROC_FS) 3218 int err; 3219 3220 err = register_pernet_subsys(&igmp_net_ops); 3221 if (err) 3222 return err; 3223 err = register_netdevice_notifier(&igmp_notifier); 3224 if (err) 3225 goto reg_notif_fail; 3226 return 0; 3227 3228 reg_notif_fail: 3229 unregister_pernet_subsys(&igmp_net_ops); 3230 return err; 3231 #else 3232 return register_netdevice_notifier(&igmp_notifier); 3233 #endif 3234 } 3235