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_u32(skb, IFA_MC_USERS, READ_ONCE(im->users)) < 0 || 1491 nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci) < 0) { 1492 nlmsg_cancel(skb, nlh); 1493 return -EMSGSIZE; 1494 } 1495 1496 nlmsg_end(skb, nlh); 1497 return 0; 1498 } 1499 1500 static void inet_ifmcaddr_notify(struct net_device *dev, 1501 const struct ip_mc_list *im, int event) 1502 { 1503 struct inet_fill_args fillargs = { 1504 .event = event, 1505 }; 1506 struct net *net = dev_net(dev); 1507 struct sk_buff *skb; 1508 int err = -ENOMEM; 1509 1510 skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) + 1511 nla_total_size(sizeof(__be32)) + 1512 nla_total_size(sizeof(u32)) + 1513 nla_total_size(sizeof(struct ifa_cacheinfo)), 1514 GFP_KERNEL); 1515 if (!skb) 1516 goto error; 1517 1518 err = inet_fill_ifmcaddr(skb, dev, im, &fillargs); 1519 if (err < 0) { 1520 WARN_ON_ONCE(err == -EMSGSIZE); 1521 nlmsg_free(skb); 1522 goto error; 1523 } 1524 1525 rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MCADDR, NULL, GFP_KERNEL); 1526 return; 1527 error: 1528 rtnl_set_sk_err(net, RTNLGRP_IPV4_MCADDR, err); 1529 } 1530 1531 /* 1532 * A socket has joined a multicast group on device dev. 1533 */ 1534 static void ____ip_mc_inc_group(struct in_device *in_dev, __be32 addr, 1535 unsigned int mode, gfp_t gfp) 1536 { 1537 struct ip_mc_list __rcu **mc_hash; 1538 struct ip_mc_list *im; 1539 1540 ASSERT_RTNL(); 1541 1542 mc_hash = rtnl_dereference(in_dev->mc_hash); 1543 if (mc_hash) { 1544 u32 hash = hash_32((__force u32)addr, MC_HASH_SZ_LOG); 1545 1546 for (im = rtnl_dereference(mc_hash[hash]); 1547 im; 1548 im = rtnl_dereference(im->next_hash)) { 1549 if (im->multiaddr == addr) 1550 break; 1551 } 1552 } else { 1553 for_each_pmc_rtnl(in_dev, im) { 1554 if (im->multiaddr == addr) 1555 break; 1556 } 1557 } 1558 1559 if (im) { 1560 WRITE_ONCE(im->users, im->users + 1); 1561 ip_mc_add_src(in_dev, &addr, mode, 0, NULL, 0); 1562 goto out; 1563 } 1564 1565 im = kzalloc_obj(*im, gfp); 1566 if (!im) 1567 goto out; 1568 1569 WRITE_ONCE(im->users, 1); 1570 im->interface = in_dev; 1571 in_dev_hold(in_dev); 1572 im->multiaddr = addr; 1573 im->mca_cstamp = jiffies; 1574 im->mca_tstamp = im->mca_cstamp; 1575 /* initial mode is (EX, empty) */ 1576 im->sfmode = mode; 1577 im->sfcount[mode] = 1; 1578 refcount_set(&im->refcnt, 1); 1579 spin_lock_init(&im->lock); 1580 #ifdef CONFIG_IP_MULTICAST 1581 timer_setup(&im->timer, igmp_timer_expire, 0); 1582 #endif 1583 1584 im->next_rcu = in_dev->mc_list; 1585 WRITE_ONCE(in_dev->mc_count, in_dev->mc_count + 1); 1586 rcu_assign_pointer(in_dev->mc_list, im); 1587 1588 ip_mc_hash_add(in_dev, im); 1589 1590 #ifdef CONFIG_IP_MULTICAST 1591 igmpv3_del_delrec(in_dev, im); 1592 #endif 1593 igmp_group_added(im); 1594 inet_ifmcaddr_notify(in_dev->dev, im, RTM_NEWMULTICAST); 1595 if (!in_dev->dead) 1596 ip_rt_multicast_event(in_dev); 1597 out: 1598 return; 1599 } 1600 1601 void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr, gfp_t gfp) 1602 { 1603 ____ip_mc_inc_group(in_dev, addr, MCAST_EXCLUDE, gfp); 1604 } 1605 EXPORT_SYMBOL(__ip_mc_inc_group); 1606 1607 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr) 1608 { 1609 __ip_mc_inc_group(in_dev, addr, GFP_KERNEL); 1610 } 1611 EXPORT_SYMBOL(ip_mc_inc_group); 1612 1613 static int ip_mc_check_iphdr(struct sk_buff *skb) 1614 { 1615 const struct iphdr *iph; 1616 unsigned int len; 1617 unsigned int offset = skb_network_offset(skb) + sizeof(*iph); 1618 1619 if (!pskb_may_pull(skb, offset)) 1620 return -EINVAL; 1621 1622 iph = ip_hdr(skb); 1623 1624 if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph)) 1625 return -EINVAL; 1626 1627 offset += ip_hdrlen(skb) - sizeof(*iph); 1628 1629 if (!pskb_may_pull(skb, offset)) 1630 return -EINVAL; 1631 1632 iph = ip_hdr(skb); 1633 1634 if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl))) 1635 return -EINVAL; 1636 1637 len = skb_network_offset(skb) + ntohs(iph->tot_len); 1638 if (skb->len < len || len < offset) 1639 return -EINVAL; 1640 1641 skb_set_transport_header(skb, offset); 1642 1643 return 0; 1644 } 1645 1646 static int ip_mc_check_igmp_reportv3(struct sk_buff *skb) 1647 { 1648 unsigned int len = skb_transport_offset(skb); 1649 1650 len += sizeof(struct igmpv3_report); 1651 1652 return ip_mc_may_pull(skb, len) ? 0 : -EINVAL; 1653 } 1654 1655 static int ip_mc_check_igmp_query(struct sk_buff *skb) 1656 { 1657 unsigned int transport_len = ip_transport_len(skb); 1658 unsigned int len; 1659 1660 /* IGMPv{1,2}? */ 1661 if (transport_len != sizeof(struct igmphdr)) { 1662 /* or IGMPv3? */ 1663 if (transport_len < sizeof(struct igmpv3_query)) 1664 return -EINVAL; 1665 1666 len = skb_transport_offset(skb) + sizeof(struct igmpv3_query); 1667 if (!ip_mc_may_pull(skb, len)) 1668 return -EINVAL; 1669 } 1670 1671 /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer 1672 * all-systems destination addresses (224.0.0.1) for general queries 1673 */ 1674 if (!igmp_hdr(skb)->group && 1675 ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP)) 1676 return -EINVAL; 1677 1678 return 0; 1679 } 1680 1681 static int ip_mc_check_igmp_msg(struct sk_buff *skb) 1682 { 1683 switch (igmp_hdr(skb)->type) { 1684 case IGMP_HOST_LEAVE_MESSAGE: 1685 case IGMP_HOST_MEMBERSHIP_REPORT: 1686 case IGMPV2_HOST_MEMBERSHIP_REPORT: 1687 return 0; 1688 case IGMPV3_HOST_MEMBERSHIP_REPORT: 1689 return ip_mc_check_igmp_reportv3(skb); 1690 case IGMP_HOST_MEMBERSHIP_QUERY: 1691 return ip_mc_check_igmp_query(skb); 1692 default: 1693 return -ENOMSG; 1694 } 1695 } 1696 1697 static __sum16 ip_mc_validate_checksum(struct sk_buff *skb) 1698 { 1699 return skb_checksum_simple_validate(skb); 1700 } 1701 1702 static int ip_mc_check_igmp_csum(struct sk_buff *skb) 1703 { 1704 unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr); 1705 unsigned int transport_len = ip_transport_len(skb); 1706 struct sk_buff *skb_chk; 1707 1708 if (!ip_mc_may_pull(skb, len)) 1709 return -EINVAL; 1710 1711 skb_chk = skb_checksum_trimmed(skb, transport_len, 1712 ip_mc_validate_checksum); 1713 if (!skb_chk) 1714 return -EINVAL; 1715 1716 if (skb_chk != skb) 1717 kfree_skb(skb_chk); 1718 1719 return 0; 1720 } 1721 1722 /** 1723 * ip_mc_check_igmp - checks whether this is a sane IGMP packet 1724 * @skb: the skb to validate 1725 * 1726 * Checks whether an IPv4 packet is a valid IGMP packet. If so sets 1727 * skb transport header accordingly and returns zero. 1728 * 1729 * -EINVAL: A broken packet was detected, i.e. it violates some internet 1730 * standard 1731 * -ENOMSG: IP header validation succeeded but it is not an IGMP packet. 1732 * -ENOMEM: A memory allocation failure happened. 1733 * 1734 * Caller needs to set the skb network header and free any returned skb if it 1735 * differs from the provided skb. 1736 */ 1737 int ip_mc_check_igmp(struct sk_buff *skb) 1738 { 1739 int ret = ip_mc_check_iphdr(skb); 1740 1741 if (ret < 0) 1742 return ret; 1743 1744 if (ip_hdr(skb)->protocol != IPPROTO_IGMP) 1745 return -ENOMSG; 1746 1747 ret = ip_mc_check_igmp_csum(skb); 1748 if (ret < 0) 1749 return ret; 1750 1751 return ip_mc_check_igmp_msg(skb); 1752 } 1753 EXPORT_SYMBOL(ip_mc_check_igmp); 1754 1755 /* 1756 * Resend IGMP JOIN report; used by netdev notifier. 1757 */ 1758 static void ip_mc_rejoin_groups(struct in_device *in_dev) 1759 { 1760 #ifdef CONFIG_IP_MULTICAST 1761 struct ip_mc_list *im; 1762 int type; 1763 struct net *net = dev_net(in_dev->dev); 1764 1765 ASSERT_RTNL(); 1766 1767 for_each_pmc_rtnl(in_dev, im) { 1768 if (im->multiaddr == IGMP_ALL_HOSTS) 1769 continue; 1770 if (ipv4_is_local_multicast(im->multiaddr) && 1771 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports)) 1772 continue; 1773 1774 /* a failover is happening and switches 1775 * must be notified immediately 1776 */ 1777 if (IGMP_V1_SEEN(in_dev)) 1778 type = IGMP_HOST_MEMBERSHIP_REPORT; 1779 else if (IGMP_V2_SEEN(in_dev)) 1780 type = IGMPV2_HOST_MEMBERSHIP_REPORT; 1781 else 1782 type = IGMPV3_HOST_MEMBERSHIP_REPORT; 1783 igmp_send_report(in_dev, im, type); 1784 } 1785 #endif 1786 } 1787 1788 /* 1789 * A socket has left a multicast group on device dev 1790 */ 1791 1792 void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp) 1793 { 1794 struct ip_mc_list *i; 1795 struct ip_mc_list __rcu **ip; 1796 1797 ASSERT_RTNL(); 1798 1799 for (ip = &in_dev->mc_list; 1800 (i = rtnl_dereference(*ip)) != NULL; 1801 ip = &i->next_rcu) { 1802 if (i->multiaddr == addr) { 1803 int new_users = i->users - 1; 1804 1805 WRITE_ONCE(i->users, new_users); 1806 if (new_users == 0) { 1807 ip_mc_hash_remove(in_dev, i); 1808 *ip = i->next_rcu; 1809 WRITE_ONCE(in_dev->mc_count, 1810 in_dev->mc_count - 1); 1811 __igmp_group_dropped(i, gfp); 1812 inet_ifmcaddr_notify(in_dev->dev, i, 1813 RTM_DELMULTICAST); 1814 ip_mc_clear_src(i); 1815 1816 if (!in_dev->dead) 1817 ip_rt_multicast_event(in_dev); 1818 1819 ip_ma_put(i); 1820 return; 1821 } 1822 break; 1823 } 1824 } 1825 } 1826 EXPORT_SYMBOL(__ip_mc_dec_group); 1827 1828 /* Device changing type */ 1829 1830 void ip_mc_unmap(struct in_device *in_dev) 1831 { 1832 struct ip_mc_list *pmc; 1833 1834 ASSERT_RTNL(); 1835 1836 for_each_pmc_rtnl(in_dev, pmc) 1837 igmp_group_dropped(pmc); 1838 } 1839 1840 void ip_mc_remap(struct in_device *in_dev) 1841 { 1842 struct ip_mc_list *pmc; 1843 1844 ASSERT_RTNL(); 1845 1846 for_each_pmc_rtnl(in_dev, pmc) { 1847 #ifdef CONFIG_IP_MULTICAST 1848 igmpv3_del_delrec(in_dev, pmc); 1849 #endif 1850 igmp_group_added(pmc); 1851 } 1852 } 1853 1854 /* Device going down */ 1855 1856 void ip_mc_down(struct in_device *in_dev) 1857 { 1858 struct ip_mc_list *pmc; 1859 1860 ASSERT_RTNL(); 1861 1862 for_each_pmc_rtnl(in_dev, pmc) 1863 igmp_group_dropped(pmc); 1864 1865 #ifdef CONFIG_IP_MULTICAST 1866 WRITE_ONCE(in_dev->mr_ifc_count, 0); 1867 if (timer_delete(&in_dev->mr_ifc_timer)) 1868 __in_dev_put(in_dev); 1869 in_dev->mr_gq_running = 0; 1870 if (timer_delete(&in_dev->mr_gq_timer)) 1871 __in_dev_put(in_dev); 1872 #endif 1873 1874 ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS); 1875 } 1876 1877 #ifdef CONFIG_IP_MULTICAST 1878 static void ip_mc_reset(struct in_device *in_dev) 1879 { 1880 struct net *net = dev_net(in_dev->dev); 1881 1882 in_dev->mr_qi = IGMP_QUERY_INTERVAL; 1883 in_dev->mr_qri = IGMP_QUERY_RESPONSE_INTERVAL; 1884 in_dev->mr_qrv = READ_ONCE(net->ipv4.sysctl_igmp_qrv); 1885 } 1886 #else 1887 static void ip_mc_reset(struct in_device *in_dev) 1888 { 1889 } 1890 #endif 1891 1892 void ip_mc_init_dev(struct in_device *in_dev) 1893 { 1894 ASSERT_RTNL(); 1895 1896 #ifdef CONFIG_IP_MULTICAST 1897 timer_setup(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 0); 1898 timer_setup(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 0); 1899 #endif 1900 ip_mc_reset(in_dev); 1901 1902 spin_lock_init(&in_dev->mc_tomb_lock); 1903 } 1904 1905 /* Device going up */ 1906 1907 void ip_mc_up(struct in_device *in_dev) 1908 { 1909 struct ip_mc_list *pmc; 1910 1911 ASSERT_RTNL(); 1912 1913 ip_mc_reset(in_dev); 1914 ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS); 1915 1916 for_each_pmc_rtnl(in_dev, pmc) { 1917 #ifdef CONFIG_IP_MULTICAST 1918 igmpv3_del_delrec(in_dev, pmc); 1919 #endif 1920 igmp_group_added(pmc); 1921 } 1922 } 1923 1924 /* 1925 * Device is about to be destroyed: clean up. 1926 */ 1927 1928 void ip_mc_destroy_dev(struct in_device *in_dev) 1929 { 1930 struct ip_mc_list *i; 1931 1932 ASSERT_RTNL(); 1933 1934 /* Deactivate timers */ 1935 ip_mc_down(in_dev); 1936 #ifdef CONFIG_IP_MULTICAST 1937 igmpv3_clear_delrec(in_dev); 1938 #endif 1939 1940 while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) { 1941 ip_mc_hash_remove(in_dev, i); 1942 in_dev->mc_list = i->next_rcu; 1943 WRITE_ONCE(in_dev->mc_count, in_dev->mc_count - 1); 1944 ip_mc_clear_src(i); 1945 ip_ma_put(i); 1946 } 1947 } 1948 1949 /* RTNL is locked */ 1950 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr) 1951 { 1952 struct net_device *dev = NULL; 1953 struct in_device *idev = NULL; 1954 1955 if (imr->imr_ifindex) { 1956 idev = inetdev_by_index(net, imr->imr_ifindex); 1957 return idev; 1958 } 1959 if (imr->imr_address.s_addr) { 1960 dev = __ip_dev_find(net, imr->imr_address.s_addr, false); 1961 if (!dev) 1962 return NULL; 1963 } 1964 1965 if (!dev) { 1966 struct rtable *rt = ip_route_output(net, 1967 imr->imr_multiaddr.s_addr, 1968 0, 0, 0, 1969 RT_SCOPE_UNIVERSE); 1970 if (!IS_ERR(rt)) { 1971 dev = rt->dst.dev; 1972 ip_rt_put(rt); 1973 } 1974 } 1975 if (dev) { 1976 imr->imr_ifindex = dev->ifindex; 1977 idev = __in_dev_get_rtnl(dev); 1978 } 1979 return idev; 1980 } 1981 1982 /* 1983 * Join a socket to a group 1984 */ 1985 1986 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode, 1987 __be32 *psfsrc) 1988 { 1989 struct ip_sf_list *psf, *psf_prev; 1990 int rv = 0; 1991 1992 psf_prev = NULL; 1993 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1994 if (psf->sf_inaddr == *psfsrc) 1995 break; 1996 psf_prev = psf; 1997 } 1998 if (!psf || psf->sf_count[sfmode] == 0) { 1999 /* source filter not found, or count wrong => bug */ 2000 return -ESRCH; 2001 } 2002 psf->sf_count[sfmode]--; 2003 if (psf->sf_count[sfmode] == 0) { 2004 ip_rt_multicast_event(pmc->interface); 2005 } 2006 if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) { 2007 #ifdef CONFIG_IP_MULTICAST 2008 struct in_device *in_dev = pmc->interface; 2009 struct net *net = dev_net(in_dev->dev); 2010 #endif 2011 2012 /* no more filters for this source */ 2013 if (psf_prev) 2014 psf_prev->sf_next = psf->sf_next; 2015 else 2016 pmc->sources = psf->sf_next; 2017 #ifdef CONFIG_IP_MULTICAST 2018 if (psf->sf_oldin && 2019 !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) { 2020 psf->sf_crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); 2021 psf->sf_next = pmc->tomb; 2022 pmc->tomb = psf; 2023 rv = 1; 2024 } else 2025 #endif 2026 kfree(psf); 2027 } 2028 return rv; 2029 } 2030 2031 #ifndef CONFIG_IP_MULTICAST 2032 #define igmp_ifc_event(x) do { } while (0) 2033 #endif 2034 2035 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 2036 int sfcount, __be32 *psfsrc, int delta) 2037 { 2038 struct ip_mc_list *pmc; 2039 int changerec = 0; 2040 int i, err; 2041 2042 if (!in_dev) 2043 return -ENODEV; 2044 rcu_read_lock(); 2045 for_each_pmc_rcu(in_dev, pmc) { 2046 if (*pmca == pmc->multiaddr) 2047 break; 2048 } 2049 if (!pmc) { 2050 /* MCA not found?? bug */ 2051 rcu_read_unlock(); 2052 return -ESRCH; 2053 } 2054 spin_lock_bh(&pmc->lock); 2055 rcu_read_unlock(); 2056 #ifdef CONFIG_IP_MULTICAST 2057 sf_markstate(pmc); 2058 #endif 2059 if (!delta) { 2060 err = -EINVAL; 2061 if (!pmc->sfcount[sfmode]) 2062 goto out_unlock; 2063 pmc->sfcount[sfmode]--; 2064 } 2065 err = 0; 2066 for (i = 0; i < sfcount; i++) { 2067 int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]); 2068 2069 changerec |= rv > 0; 2070 if (!err && rv < 0) 2071 err = rv; 2072 } 2073 if (pmc->sfmode == MCAST_EXCLUDE && 2074 pmc->sfcount[MCAST_EXCLUDE] == 0 && 2075 pmc->sfcount[MCAST_INCLUDE]) { 2076 #ifdef CONFIG_IP_MULTICAST 2077 struct ip_sf_list *psf; 2078 struct net *net = dev_net(in_dev->dev); 2079 #endif 2080 2081 /* filter mode change */ 2082 pmc->sfmode = MCAST_INCLUDE; 2083 #ifdef CONFIG_IP_MULTICAST 2084 pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); 2085 WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount); 2086 for (psf = pmc->sources; psf; psf = psf->sf_next) 2087 psf->sf_crcount = 0; 2088 igmp_ifc_event(pmc->interface); 2089 } else if (sf_setstate(pmc) || changerec) { 2090 igmp_ifc_event(pmc->interface); 2091 #endif 2092 } 2093 out_unlock: 2094 spin_unlock_bh(&pmc->lock); 2095 return err; 2096 } 2097 2098 /* 2099 * Add multicast single-source filter to the interface list 2100 */ 2101 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode, 2102 __be32 *psfsrc) 2103 { 2104 struct ip_sf_list *psf, *psf_prev; 2105 2106 psf_prev = NULL; 2107 for (psf = pmc->sources; psf; psf = psf->sf_next) { 2108 if (psf->sf_inaddr == *psfsrc) 2109 break; 2110 psf_prev = psf; 2111 } 2112 if (!psf) { 2113 psf = kzalloc_obj(*psf, GFP_ATOMIC); 2114 if (!psf) 2115 return -ENOBUFS; 2116 psf->sf_inaddr = *psfsrc; 2117 if (psf_prev) { 2118 psf_prev->sf_next = psf; 2119 } else 2120 pmc->sources = psf; 2121 } 2122 psf->sf_count[sfmode]++; 2123 if (psf->sf_count[sfmode] == 1) { 2124 ip_rt_multicast_event(pmc->interface); 2125 } 2126 return 0; 2127 } 2128 2129 #ifdef CONFIG_IP_MULTICAST 2130 static void sf_markstate(struct ip_mc_list *pmc) 2131 { 2132 struct ip_sf_list *psf; 2133 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; 2134 2135 for (psf = pmc->sources; psf; psf = psf->sf_next) 2136 if (pmc->sfcount[MCAST_EXCLUDE]) { 2137 psf->sf_oldin = mca_xcount == 2138 psf->sf_count[MCAST_EXCLUDE] && 2139 !psf->sf_count[MCAST_INCLUDE]; 2140 } else 2141 psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0; 2142 } 2143 2144 static int sf_setstate(struct ip_mc_list *pmc) 2145 { 2146 struct ip_sf_list *psf, *dpsf; 2147 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; 2148 int qrv = pmc->interface->mr_qrv; 2149 int new_in, rv; 2150 2151 rv = 0; 2152 for (psf = pmc->sources; psf; psf = psf->sf_next) { 2153 if (pmc->sfcount[MCAST_EXCLUDE]) { 2154 new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] && 2155 !psf->sf_count[MCAST_INCLUDE]; 2156 } else 2157 new_in = psf->sf_count[MCAST_INCLUDE] != 0; 2158 if (new_in) { 2159 if (!psf->sf_oldin) { 2160 struct ip_sf_list *prev = NULL; 2161 2162 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) { 2163 if (dpsf->sf_inaddr == psf->sf_inaddr) 2164 break; 2165 prev = dpsf; 2166 } 2167 if (dpsf) { 2168 if (prev) 2169 prev->sf_next = dpsf->sf_next; 2170 else 2171 pmc->tomb = dpsf->sf_next; 2172 kfree(dpsf); 2173 } 2174 psf->sf_crcount = qrv; 2175 rv++; 2176 } 2177 } else if (psf->sf_oldin) { 2178 2179 psf->sf_crcount = 0; 2180 /* 2181 * add or update "delete" records if an active filter 2182 * is now inactive 2183 */ 2184 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) 2185 if (dpsf->sf_inaddr == psf->sf_inaddr) 2186 break; 2187 if (!dpsf) { 2188 dpsf = kmalloc_obj(*dpsf, GFP_ATOMIC); 2189 if (!dpsf) 2190 continue; 2191 *dpsf = *psf; 2192 /* pmc->lock held by callers */ 2193 dpsf->sf_next = pmc->tomb; 2194 pmc->tomb = dpsf; 2195 } 2196 dpsf->sf_crcount = qrv; 2197 rv++; 2198 } 2199 } 2200 return rv; 2201 } 2202 #endif 2203 2204 /* 2205 * Add multicast source filter list to the interface list 2206 */ 2207 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 2208 int sfcount, __be32 *psfsrc, int delta) 2209 { 2210 struct ip_mc_list *pmc; 2211 int isexclude; 2212 int i, err; 2213 2214 if (!in_dev) 2215 return -ENODEV; 2216 rcu_read_lock(); 2217 for_each_pmc_rcu(in_dev, pmc) { 2218 if (*pmca == pmc->multiaddr) 2219 break; 2220 } 2221 if (!pmc) { 2222 /* MCA not found?? bug */ 2223 rcu_read_unlock(); 2224 return -ESRCH; 2225 } 2226 spin_lock_bh(&pmc->lock); 2227 rcu_read_unlock(); 2228 2229 #ifdef CONFIG_IP_MULTICAST 2230 sf_markstate(pmc); 2231 #endif 2232 isexclude = pmc->sfmode == MCAST_EXCLUDE; 2233 if (!delta) 2234 pmc->sfcount[sfmode]++; 2235 err = 0; 2236 for (i = 0; i < sfcount; i++) { 2237 err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]); 2238 if (err) 2239 break; 2240 } 2241 if (err) { 2242 int j; 2243 2244 if (!delta) 2245 pmc->sfcount[sfmode]--; 2246 for (j = 0; j < i; j++) 2247 (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]); 2248 } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) { 2249 #ifdef CONFIG_IP_MULTICAST 2250 struct ip_sf_list *psf; 2251 struct net *net = dev_net(pmc->interface->dev); 2252 in_dev = pmc->interface; 2253 #endif 2254 2255 /* filter mode change */ 2256 if (pmc->sfcount[MCAST_EXCLUDE]) 2257 pmc->sfmode = MCAST_EXCLUDE; 2258 else if (pmc->sfcount[MCAST_INCLUDE]) 2259 pmc->sfmode = MCAST_INCLUDE; 2260 #ifdef CONFIG_IP_MULTICAST 2261 /* else no filters; keep old mode for reports */ 2262 2263 pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); 2264 WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount); 2265 for (psf = pmc->sources; psf; psf = psf->sf_next) 2266 psf->sf_crcount = 0; 2267 igmp_ifc_event(in_dev); 2268 } else if (sf_setstate(pmc)) { 2269 igmp_ifc_event(in_dev); 2270 #endif 2271 } 2272 spin_unlock_bh(&pmc->lock); 2273 return err; 2274 } 2275 2276 static void ip_mc_clear_src(struct ip_mc_list *pmc) 2277 { 2278 struct ip_sf_list *tomb, *sources; 2279 2280 spin_lock_bh(&pmc->lock); 2281 tomb = pmc->tomb; 2282 pmc->tomb = NULL; 2283 sources = pmc->sources; 2284 pmc->sources = NULL; 2285 pmc->sfmode = MCAST_EXCLUDE; 2286 pmc->sfcount[MCAST_INCLUDE] = 0; 2287 pmc->sfcount[MCAST_EXCLUDE] = 1; 2288 spin_unlock_bh(&pmc->lock); 2289 2290 ip_sf_list_clear_all(tomb); 2291 ip_sf_list_clear_all(sources); 2292 } 2293 2294 /* Join a multicast group 2295 */ 2296 static int __ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr, 2297 unsigned int mode) 2298 { 2299 __be32 addr = imr->imr_multiaddr.s_addr; 2300 struct ip_mc_socklist *iml, *i; 2301 struct in_device *in_dev; 2302 struct inet_sock *inet = inet_sk(sk); 2303 struct net *net = sock_net(sk); 2304 int ifindex; 2305 int count = 0; 2306 int err; 2307 2308 ASSERT_RTNL(); 2309 2310 if (!ipv4_is_multicast(addr)) 2311 return -EINVAL; 2312 2313 in_dev = ip_mc_find_dev(net, imr); 2314 2315 if (!in_dev) { 2316 err = -ENODEV; 2317 goto done; 2318 } 2319 2320 err = -EADDRINUSE; 2321 ifindex = imr->imr_ifindex; 2322 for_each_pmc_rtnl(inet, i) { 2323 if (i->multi.imr_multiaddr.s_addr == addr && 2324 i->multi.imr_ifindex == ifindex) 2325 goto done; 2326 count++; 2327 } 2328 err = -ENOBUFS; 2329 if (count >= READ_ONCE(net->ipv4.sysctl_igmp_max_memberships)) 2330 goto done; 2331 iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL); 2332 if (!iml) 2333 goto done; 2334 2335 memcpy(&iml->multi, imr, sizeof(*imr)); 2336 iml->next_rcu = inet->mc_list; 2337 iml->sflist = NULL; 2338 iml->sfmode = mode; 2339 rcu_assign_pointer(inet->mc_list, iml); 2340 ____ip_mc_inc_group(in_dev, addr, mode, GFP_KERNEL); 2341 err = 0; 2342 done: 2343 return err; 2344 } 2345 2346 /* Join ASM (Any-Source Multicast) group 2347 */ 2348 int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr) 2349 { 2350 return __ip_mc_join_group(sk, imr, MCAST_EXCLUDE); 2351 } 2352 EXPORT_SYMBOL(ip_mc_join_group); 2353 2354 /* Join SSM (Source-Specific Multicast) group 2355 */ 2356 int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr, 2357 unsigned int mode) 2358 { 2359 return __ip_mc_join_group(sk, imr, mode); 2360 } 2361 2362 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml, 2363 struct in_device *in_dev) 2364 { 2365 struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist); 2366 int err; 2367 2368 if (!psf) { 2369 /* any-source empty exclude case */ 2370 return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, 2371 iml->sfmode, 0, NULL, 0); 2372 } 2373 err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, 2374 iml->sfmode, psf->sl_count, psf->sl_addr, 0); 2375 RCU_INIT_POINTER(iml->sflist, NULL); 2376 /* decrease mem now to avoid the memleak warning */ 2377 atomic_sub(struct_size(psf, sl_addr, psf->sl_max), &sk->sk_omem_alloc); 2378 kfree_rcu(psf, rcu); 2379 return err; 2380 } 2381 2382 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr) 2383 { 2384 struct inet_sock *inet = inet_sk(sk); 2385 struct ip_mc_socklist *iml; 2386 struct ip_mc_socklist __rcu **imlp; 2387 struct in_device *in_dev; 2388 struct net *net = sock_net(sk); 2389 __be32 group = imr->imr_multiaddr.s_addr; 2390 u32 ifindex; 2391 int ret = -EADDRNOTAVAIL; 2392 2393 ASSERT_RTNL(); 2394 2395 in_dev = ip_mc_find_dev(net, imr); 2396 if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) { 2397 ret = -ENODEV; 2398 goto out; 2399 } 2400 ifindex = imr->imr_ifindex; 2401 for (imlp = &inet->mc_list; 2402 (iml = rtnl_dereference(*imlp)) != NULL; 2403 imlp = &iml->next_rcu) { 2404 if (iml->multi.imr_multiaddr.s_addr != group) 2405 continue; 2406 if (ifindex) { 2407 if (iml->multi.imr_ifindex != ifindex) 2408 continue; 2409 } else if (imr->imr_address.s_addr && imr->imr_address.s_addr != 2410 iml->multi.imr_address.s_addr) 2411 continue; 2412 2413 (void) ip_mc_leave_src(sk, iml, in_dev); 2414 2415 *imlp = iml->next_rcu; 2416 2417 if (in_dev) 2418 ip_mc_dec_group(in_dev, group); 2419 2420 /* decrease mem now to avoid the memleak warning */ 2421 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); 2422 kfree_rcu(iml, rcu); 2423 return 0; 2424 } 2425 out: 2426 return ret; 2427 } 2428 EXPORT_SYMBOL(ip_mc_leave_group); 2429 2430 int ip_mc_source(int add, int omode, struct sock *sk, struct 2431 ip_mreq_source *mreqs, int ifindex) 2432 { 2433 int err; 2434 struct ip_mreqn imr; 2435 __be32 addr = mreqs->imr_multiaddr; 2436 struct ip_mc_socklist *pmc; 2437 struct in_device *in_dev = NULL; 2438 struct inet_sock *inet = inet_sk(sk); 2439 struct ip_sf_socklist *psl; 2440 struct net *net = sock_net(sk); 2441 int leavegroup = 0; 2442 int i, j, rv; 2443 2444 if (!ipv4_is_multicast(addr)) 2445 return -EINVAL; 2446 2447 ASSERT_RTNL(); 2448 2449 imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr; 2450 imr.imr_address.s_addr = mreqs->imr_interface; 2451 imr.imr_ifindex = ifindex; 2452 in_dev = ip_mc_find_dev(net, &imr); 2453 2454 if (!in_dev) { 2455 err = -ENODEV; 2456 goto done; 2457 } 2458 err = -EADDRNOTAVAIL; 2459 2460 for_each_pmc_rtnl(inet, pmc) { 2461 if ((pmc->multi.imr_multiaddr.s_addr == 2462 imr.imr_multiaddr.s_addr) && 2463 (pmc->multi.imr_ifindex == imr.imr_ifindex)) 2464 break; 2465 } 2466 if (!pmc) { /* must have a prior join */ 2467 err = -EINVAL; 2468 goto done; 2469 } 2470 /* if a source filter was set, must be the same mode as before */ 2471 if (pmc->sflist) { 2472 if (pmc->sfmode != omode) { 2473 err = -EINVAL; 2474 goto done; 2475 } 2476 } else if (pmc->sfmode != omode) { 2477 /* allow mode switches for empty-set filters */ 2478 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0); 2479 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0, 2480 NULL, 0); 2481 pmc->sfmode = omode; 2482 } 2483 2484 psl = rtnl_dereference(pmc->sflist); 2485 if (!add) { 2486 if (!psl) 2487 goto done; /* err = -EADDRNOTAVAIL */ 2488 rv = !0; 2489 for (i = 0; i < psl->sl_count; i++) { 2490 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr, 2491 sizeof(__be32)); 2492 if (rv == 0) 2493 break; 2494 } 2495 if (rv) /* source not found */ 2496 goto done; /* err = -EADDRNOTAVAIL */ 2497 2498 /* special case - (INCLUDE, empty) == LEAVE_GROUP */ 2499 if (psl->sl_count == 1 && omode == MCAST_INCLUDE) { 2500 leavegroup = 1; 2501 goto done; 2502 } 2503 2504 /* update the interface filter */ 2505 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1, 2506 &mreqs->imr_sourceaddr, 1); 2507 2508 for (j = i+1; j < psl->sl_count; j++) 2509 psl->sl_addr[j-1] = psl->sl_addr[j]; 2510 psl->sl_count--; 2511 err = 0; 2512 goto done; 2513 } 2514 /* else, add a new source to the filter */ 2515 2516 if (psl && psl->sl_count >= READ_ONCE(net->ipv4.sysctl_igmp_max_msf)) { 2517 err = -ENOBUFS; 2518 goto done; 2519 } 2520 if (!psl || psl->sl_count == psl->sl_max) { 2521 struct ip_sf_socklist *newpsl; 2522 int count = IP_SFBLOCK; 2523 2524 if (psl) 2525 count += psl->sl_max; 2526 newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr, count), 2527 GFP_KERNEL); 2528 if (!newpsl) { 2529 err = -ENOBUFS; 2530 goto done; 2531 } 2532 newpsl->sl_max = count; 2533 newpsl->sl_count = count - IP_SFBLOCK; 2534 if (psl) { 2535 for (i = 0; i < psl->sl_count; i++) 2536 newpsl->sl_addr[i] = psl->sl_addr[i]; 2537 /* decrease mem now to avoid the memleak warning */ 2538 atomic_sub(struct_size(psl, sl_addr, psl->sl_max), 2539 &sk->sk_omem_alloc); 2540 } 2541 rcu_assign_pointer(pmc->sflist, newpsl); 2542 if (psl) 2543 kfree_rcu(psl, rcu); 2544 psl = newpsl; 2545 } 2546 rv = 1; /* > 0 for insert logic below if sl_count is 0 */ 2547 for (i = 0; i < psl->sl_count; i++) { 2548 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr, 2549 sizeof(__be32)); 2550 if (rv == 0) 2551 break; 2552 } 2553 if (rv == 0) /* address already there is an error */ 2554 goto done; 2555 for (j = psl->sl_count-1; j >= i; j--) 2556 psl->sl_addr[j+1] = psl->sl_addr[j]; 2557 psl->sl_addr[i] = mreqs->imr_sourceaddr; 2558 psl->sl_count++; 2559 err = 0; 2560 /* update the interface list */ 2561 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1, 2562 &mreqs->imr_sourceaddr, 1); 2563 done: 2564 if (leavegroup) 2565 err = ip_mc_leave_group(sk, &imr); 2566 return err; 2567 } 2568 2569 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex) 2570 { 2571 int err = 0; 2572 struct ip_mreqn imr; 2573 __be32 addr = msf->imsf_multiaddr; 2574 struct ip_mc_socklist *pmc; 2575 struct in_device *in_dev; 2576 struct inet_sock *inet = inet_sk(sk); 2577 struct ip_sf_socklist *newpsl, *psl; 2578 struct net *net = sock_net(sk); 2579 int leavegroup = 0; 2580 2581 if (!ipv4_is_multicast(addr)) 2582 return -EINVAL; 2583 if (msf->imsf_fmode != MCAST_INCLUDE && 2584 msf->imsf_fmode != MCAST_EXCLUDE) 2585 return -EINVAL; 2586 2587 ASSERT_RTNL(); 2588 2589 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; 2590 imr.imr_address.s_addr = msf->imsf_interface; 2591 imr.imr_ifindex = ifindex; 2592 in_dev = ip_mc_find_dev(net, &imr); 2593 2594 if (!in_dev) { 2595 err = -ENODEV; 2596 goto done; 2597 } 2598 2599 /* special case - (INCLUDE, empty) == LEAVE_GROUP */ 2600 if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) { 2601 leavegroup = 1; 2602 goto done; 2603 } 2604 2605 for_each_pmc_rtnl(inet, pmc) { 2606 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && 2607 pmc->multi.imr_ifindex == imr.imr_ifindex) 2608 break; 2609 } 2610 if (!pmc) { /* must have a prior join */ 2611 err = -EINVAL; 2612 goto done; 2613 } 2614 if (msf->imsf_numsrc) { 2615 newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr, 2616 msf->imsf_numsrc), 2617 GFP_KERNEL); 2618 if (!newpsl) { 2619 err = -ENOBUFS; 2620 goto done; 2621 } 2622 newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc; 2623 memcpy(newpsl->sl_addr, msf->imsf_slist_flex, 2624 flex_array_size(msf, imsf_slist_flex, msf->imsf_numsrc)); 2625 err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr, 2626 msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0); 2627 if (err) { 2628 sock_kfree_s(sk, newpsl, 2629 struct_size(newpsl, sl_addr, 2630 newpsl->sl_max)); 2631 goto done; 2632 } 2633 } else { 2634 newpsl = NULL; 2635 (void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr, 2636 msf->imsf_fmode, 0, NULL, 0); 2637 } 2638 psl = rtnl_dereference(pmc->sflist); 2639 if (psl) { 2640 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, 2641 psl->sl_count, psl->sl_addr, 0); 2642 /* decrease mem now to avoid the memleak warning */ 2643 atomic_sub(struct_size(psl, sl_addr, psl->sl_max), 2644 &sk->sk_omem_alloc); 2645 } else { 2646 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, 2647 0, NULL, 0); 2648 } 2649 rcu_assign_pointer(pmc->sflist, newpsl); 2650 if (psl) 2651 kfree_rcu(psl, rcu); 2652 pmc->sfmode = msf->imsf_fmode; 2653 err = 0; 2654 done: 2655 if (leavegroup) 2656 err = ip_mc_leave_group(sk, &imr); 2657 return err; 2658 } 2659 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf, 2660 sockptr_t optval, sockptr_t optlen) 2661 { 2662 int err, len, count, copycount, msf_size; 2663 struct ip_mreqn imr; 2664 __be32 addr = msf->imsf_multiaddr; 2665 struct ip_mc_socklist *pmc; 2666 struct in_device *in_dev; 2667 struct inet_sock *inet = inet_sk(sk); 2668 struct ip_sf_socklist *psl; 2669 struct net *net = sock_net(sk); 2670 2671 ASSERT_RTNL(); 2672 2673 if (!ipv4_is_multicast(addr)) 2674 return -EINVAL; 2675 2676 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; 2677 imr.imr_address.s_addr = msf->imsf_interface; 2678 imr.imr_ifindex = 0; 2679 in_dev = ip_mc_find_dev(net, &imr); 2680 2681 if (!in_dev) { 2682 err = -ENODEV; 2683 goto done; 2684 } 2685 err = -EADDRNOTAVAIL; 2686 2687 for_each_pmc_rtnl(inet, pmc) { 2688 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && 2689 pmc->multi.imr_ifindex == imr.imr_ifindex) 2690 break; 2691 } 2692 if (!pmc) /* must have a prior join */ 2693 goto done; 2694 msf->imsf_fmode = pmc->sfmode; 2695 psl = rtnl_dereference(pmc->sflist); 2696 if (!psl) { 2697 count = 0; 2698 } else { 2699 count = psl->sl_count; 2700 } 2701 copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc; 2702 len = flex_array_size(psl, sl_addr, copycount); 2703 msf->imsf_numsrc = count; 2704 msf_size = IP_MSFILTER_SIZE(copycount); 2705 if (copy_to_sockptr(optlen, &msf_size, sizeof(int)) || 2706 copy_to_sockptr(optval, msf, IP_MSFILTER_SIZE(0))) { 2707 return -EFAULT; 2708 } 2709 if (len && 2710 copy_to_sockptr_offset(optval, 2711 offsetof(struct ip_msfilter, imsf_slist_flex), 2712 psl->sl_addr, len)) 2713 return -EFAULT; 2714 return 0; 2715 done: 2716 return err; 2717 } 2718 2719 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf, 2720 sockptr_t optval, size_t ss_offset) 2721 { 2722 int i, count, copycount; 2723 struct sockaddr_in *psin; 2724 __be32 addr; 2725 struct ip_mc_socklist *pmc; 2726 struct inet_sock *inet = inet_sk(sk); 2727 struct ip_sf_socklist *psl; 2728 2729 ASSERT_RTNL(); 2730 2731 psin = (struct sockaddr_in *)&gsf->gf_group; 2732 if (psin->sin_family != AF_INET) 2733 return -EINVAL; 2734 addr = psin->sin_addr.s_addr; 2735 if (!ipv4_is_multicast(addr)) 2736 return -EINVAL; 2737 2738 for_each_pmc_rtnl(inet, pmc) { 2739 if (pmc->multi.imr_multiaddr.s_addr == addr && 2740 pmc->multi.imr_ifindex == gsf->gf_interface) 2741 break; 2742 } 2743 if (!pmc) /* must have a prior join */ 2744 return -EADDRNOTAVAIL; 2745 gsf->gf_fmode = pmc->sfmode; 2746 psl = rtnl_dereference(pmc->sflist); 2747 count = psl ? psl->sl_count : 0; 2748 copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc; 2749 gsf->gf_numsrc = count; 2750 for (i = 0; i < copycount; i++) { 2751 struct sockaddr_storage ss; 2752 2753 psin = (struct sockaddr_in *)&ss; 2754 memset(&ss, 0, sizeof(ss)); 2755 psin->sin_family = AF_INET; 2756 psin->sin_addr.s_addr = psl->sl_addr[i]; 2757 if (copy_to_sockptr_offset(optval, ss_offset, 2758 &ss, sizeof(ss))) 2759 return -EFAULT; 2760 ss_offset += sizeof(ss); 2761 } 2762 return 0; 2763 } 2764 2765 /* 2766 * check if a multicast source filter allows delivery for a given <src,dst,intf> 2767 */ 2768 int ip_mc_sf_allow(const struct sock *sk, __be32 loc_addr, __be32 rmt_addr, 2769 int dif, int sdif) 2770 { 2771 const struct inet_sock *inet = inet_sk(sk); 2772 struct ip_mc_socklist *pmc; 2773 struct ip_sf_socklist *psl; 2774 int i; 2775 int ret; 2776 2777 ret = 1; 2778 if (!ipv4_is_multicast(loc_addr)) 2779 goto out; 2780 2781 rcu_read_lock(); 2782 for_each_pmc_rcu(inet, pmc) { 2783 if (pmc->multi.imr_multiaddr.s_addr == loc_addr && 2784 (pmc->multi.imr_ifindex == dif || 2785 (sdif && pmc->multi.imr_ifindex == sdif))) 2786 break; 2787 } 2788 ret = inet_test_bit(MC_ALL, sk); 2789 if (!pmc) 2790 goto unlock; 2791 psl = rcu_dereference(pmc->sflist); 2792 ret = (pmc->sfmode == MCAST_EXCLUDE); 2793 if (!psl) 2794 goto unlock; 2795 2796 for (i = 0; i < psl->sl_count; i++) { 2797 if (psl->sl_addr[i] == rmt_addr) 2798 break; 2799 } 2800 ret = 0; 2801 if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count) 2802 goto unlock; 2803 if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count) 2804 goto unlock; 2805 ret = 1; 2806 unlock: 2807 rcu_read_unlock(); 2808 out: 2809 return ret; 2810 } 2811 2812 /* 2813 * A socket is closing. 2814 */ 2815 2816 void ip_mc_drop_socket(struct sock *sk) 2817 { 2818 struct inet_sock *inet = inet_sk(sk); 2819 struct ip_mc_socklist *iml; 2820 struct net *net = sock_net(sk); 2821 2822 if (!inet->mc_list) 2823 return; 2824 2825 rtnl_lock(); 2826 while ((iml = rtnl_dereference(inet->mc_list)) != NULL) { 2827 struct in_device *in_dev; 2828 2829 inet->mc_list = iml->next_rcu; 2830 in_dev = inetdev_by_index(net, iml->multi.imr_ifindex); 2831 (void) ip_mc_leave_src(sk, iml, in_dev); 2832 if (in_dev) 2833 ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr); 2834 /* decrease mem now to avoid the memleak warning */ 2835 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); 2836 kfree_rcu(iml, rcu); 2837 } 2838 rtnl_unlock(); 2839 } 2840 2841 /* called with rcu_read_lock() */ 2842 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto) 2843 { 2844 struct ip_mc_list *im; 2845 struct ip_mc_list __rcu **mc_hash; 2846 struct ip_sf_list *psf; 2847 int rv = 0; 2848 2849 mc_hash = rcu_dereference(in_dev->mc_hash); 2850 if (mc_hash) { 2851 u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG); 2852 2853 for (im = rcu_dereference(mc_hash[hash]); 2854 im != NULL; 2855 im = rcu_dereference(im->next_hash)) { 2856 if (im->multiaddr == mc_addr) 2857 break; 2858 } 2859 } else { 2860 for_each_pmc_rcu(in_dev, im) { 2861 if (im->multiaddr == mc_addr) 2862 break; 2863 } 2864 } 2865 if (im && proto == IPPROTO_IGMP) { 2866 rv = 1; 2867 } else if (im) { 2868 if (src_addr) { 2869 spin_lock_bh(&im->lock); 2870 for (psf = im->sources; psf; psf = psf->sf_next) { 2871 if (psf->sf_inaddr == src_addr) 2872 break; 2873 } 2874 if (psf) 2875 rv = psf->sf_count[MCAST_INCLUDE] || 2876 psf->sf_count[MCAST_EXCLUDE] != 2877 im->sfcount[MCAST_EXCLUDE]; 2878 else 2879 rv = im->sfcount[MCAST_EXCLUDE] != 0; 2880 spin_unlock_bh(&im->lock); 2881 } else 2882 rv = 1; /* unspecified source; tentatively allow */ 2883 } 2884 return rv; 2885 } 2886 2887 #if defined(CONFIG_PROC_FS) 2888 struct igmp_mc_iter_state { 2889 struct seq_net_private p; 2890 struct net_device *dev; 2891 struct in_device *in_dev; 2892 }; 2893 2894 #define igmp_mc_seq_private(seq) ((struct igmp_mc_iter_state *)(seq)->private) 2895 2896 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq) 2897 { 2898 struct net *net = seq_file_net(seq); 2899 struct ip_mc_list *im = NULL; 2900 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2901 2902 state->in_dev = NULL; 2903 for_each_netdev_rcu(net, state->dev) { 2904 struct in_device *in_dev; 2905 2906 in_dev = __in_dev_get_rcu(state->dev); 2907 if (!in_dev) 2908 continue; 2909 im = rcu_dereference(in_dev->mc_list); 2910 if (im) { 2911 state->in_dev = in_dev; 2912 break; 2913 } 2914 } 2915 return im; 2916 } 2917 2918 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im) 2919 { 2920 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2921 2922 im = rcu_dereference(im->next_rcu); 2923 while (!im) { 2924 state->dev = next_net_device_rcu(state->dev); 2925 if (!state->dev) { 2926 state->in_dev = NULL; 2927 break; 2928 } 2929 state->in_dev = __in_dev_get_rcu(state->dev); 2930 if (!state->in_dev) 2931 continue; 2932 im = rcu_dereference(state->in_dev->mc_list); 2933 } 2934 return im; 2935 } 2936 2937 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos) 2938 { 2939 struct ip_mc_list *im = igmp_mc_get_first(seq); 2940 if (im) 2941 while (pos && (im = igmp_mc_get_next(seq, im)) != NULL) 2942 --pos; 2943 return pos ? NULL : im; 2944 } 2945 2946 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos) 2947 __acquires(rcu) 2948 { 2949 rcu_read_lock(); 2950 return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 2951 } 2952 2953 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2954 { 2955 struct ip_mc_list *im; 2956 if (v == SEQ_START_TOKEN) 2957 im = igmp_mc_get_first(seq); 2958 else 2959 im = igmp_mc_get_next(seq, v); 2960 ++*pos; 2961 return im; 2962 } 2963 2964 static void igmp_mc_seq_stop(struct seq_file *seq, void *v) 2965 __releases(rcu) 2966 { 2967 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2968 2969 state->in_dev = NULL; 2970 state->dev = NULL; 2971 rcu_read_unlock(); 2972 } 2973 2974 static int igmp_mc_seq_show(struct seq_file *seq, void *v) 2975 { 2976 if (v == SEQ_START_TOKEN) 2977 seq_puts(seq, 2978 "Idx\tDevice : Count Querier\tGroup Users Timer\tReporter\n"); 2979 else { 2980 struct ip_mc_list *im = v; 2981 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2982 char *querier; 2983 int tm_running; 2984 long delta; 2985 2986 #ifdef CONFIG_IP_MULTICAST 2987 querier = IGMP_V1_SEEN(state->in_dev) ? "V1" : 2988 IGMP_V2_SEEN(state->in_dev) ? "V2" : 2989 "V3"; 2990 #else 2991 querier = "NONE"; 2992 #endif 2993 2994 if (rcu_access_pointer(state->in_dev->mc_list) == im) { 2995 seq_printf(seq, "%d\t%-10s: %5d %7s\n", 2996 state->dev->ifindex, state->dev->name, 2997 READ_ONCE(state->in_dev->mc_count), 2998 querier); 2999 } 3000 3001 tm_running = READ_ONCE(im->tm_running); 3002 delta = READ_ONCE(im->timer.expires) - jiffies; 3003 seq_printf(seq, 3004 "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n", 3005 im->multiaddr, READ_ONCE(im->users), 3006 tm_running, 3007 tm_running ? jiffies_delta_to_clock_t(delta) : 0, 3008 READ_ONCE(im->reporter)); 3009 } 3010 return 0; 3011 } 3012 3013 static const struct seq_operations igmp_mc_seq_ops = { 3014 .start = igmp_mc_seq_start, 3015 .next = igmp_mc_seq_next, 3016 .stop = igmp_mc_seq_stop, 3017 .show = igmp_mc_seq_show, 3018 }; 3019 3020 struct igmp_mcf_iter_state { 3021 struct seq_net_private p; 3022 struct net_device *dev; 3023 struct in_device *idev; 3024 struct ip_mc_list *im; 3025 }; 3026 3027 #define igmp_mcf_seq_private(seq) ((struct igmp_mcf_iter_state *)(seq)->private) 3028 3029 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq) 3030 { 3031 struct net *net = seq_file_net(seq); 3032 struct ip_sf_list *psf = NULL; 3033 struct ip_mc_list *im = NULL; 3034 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 3035 3036 state->idev = NULL; 3037 state->im = NULL; 3038 for_each_netdev_rcu(net, state->dev) { 3039 struct in_device *idev; 3040 idev = __in_dev_get_rcu(state->dev); 3041 if (unlikely(!idev)) 3042 continue; 3043 im = rcu_dereference(idev->mc_list); 3044 if (likely(im)) { 3045 spin_lock_bh(&im->lock); 3046 psf = im->sources; 3047 if (likely(psf)) { 3048 state->im = im; 3049 state->idev = idev; 3050 break; 3051 } 3052 spin_unlock_bh(&im->lock); 3053 } 3054 } 3055 return psf; 3056 } 3057 3058 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf) 3059 { 3060 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 3061 3062 psf = psf->sf_next; 3063 while (!psf) { 3064 spin_unlock_bh(&state->im->lock); 3065 state->im = state->im->next; 3066 while (!state->im) { 3067 state->dev = next_net_device_rcu(state->dev); 3068 if (!state->dev) { 3069 state->idev = NULL; 3070 goto out; 3071 } 3072 state->idev = __in_dev_get_rcu(state->dev); 3073 if (!state->idev) 3074 continue; 3075 state->im = rcu_dereference(state->idev->mc_list); 3076 } 3077 spin_lock_bh(&state->im->lock); 3078 psf = state->im->sources; 3079 } 3080 out: 3081 return psf; 3082 } 3083 3084 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos) 3085 { 3086 struct ip_sf_list *psf = igmp_mcf_get_first(seq); 3087 if (psf) 3088 while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL) 3089 --pos; 3090 return pos ? NULL : psf; 3091 } 3092 3093 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos) 3094 __acquires(rcu) 3095 { 3096 rcu_read_lock(); 3097 return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 3098 } 3099 3100 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos) 3101 { 3102 struct ip_sf_list *psf; 3103 if (v == SEQ_START_TOKEN) 3104 psf = igmp_mcf_get_first(seq); 3105 else 3106 psf = igmp_mcf_get_next(seq, v); 3107 ++*pos; 3108 return psf; 3109 } 3110 3111 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v) 3112 __releases(rcu) 3113 { 3114 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 3115 if (likely(state->im)) { 3116 spin_unlock_bh(&state->im->lock); 3117 state->im = NULL; 3118 } 3119 state->idev = NULL; 3120 state->dev = NULL; 3121 rcu_read_unlock(); 3122 } 3123 3124 static int igmp_mcf_seq_show(struct seq_file *seq, void *v) 3125 { 3126 struct ip_sf_list *psf = v; 3127 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 3128 3129 if (v == SEQ_START_TOKEN) { 3130 seq_puts(seq, "Idx Device MCA SRC INC EXC\n"); 3131 } else { 3132 seq_printf(seq, 3133 "%3d %6.6s 0x%08x " 3134 "0x%08x %6lu %6lu\n", 3135 state->dev->ifindex, state->dev->name, 3136 ntohl(state->im->multiaddr), 3137 ntohl(psf->sf_inaddr), 3138 psf->sf_count[MCAST_INCLUDE], 3139 psf->sf_count[MCAST_EXCLUDE]); 3140 } 3141 return 0; 3142 } 3143 3144 static const struct seq_operations igmp_mcf_seq_ops = { 3145 .start = igmp_mcf_seq_start, 3146 .next = igmp_mcf_seq_next, 3147 .stop = igmp_mcf_seq_stop, 3148 .show = igmp_mcf_seq_show, 3149 }; 3150 3151 static int __net_init igmp_net_init(struct net *net) 3152 { 3153 struct proc_dir_entry *pde; 3154 int err; 3155 3156 pde = proc_create_net("igmp", 0444, net->proc_net, &igmp_mc_seq_ops, 3157 sizeof(struct igmp_mc_iter_state)); 3158 if (!pde) 3159 goto out_igmp; 3160 pde = proc_create_net("mcfilter", 0444, net->proc_net, 3161 &igmp_mcf_seq_ops, sizeof(struct igmp_mcf_iter_state)); 3162 if (!pde) 3163 goto out_mcfilter; 3164 err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET, 3165 SOCK_DGRAM, 0, net); 3166 if (err < 0) { 3167 pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n", 3168 err); 3169 goto out_sock; 3170 } 3171 3172 return 0; 3173 3174 out_sock: 3175 remove_proc_entry("mcfilter", net->proc_net); 3176 out_mcfilter: 3177 remove_proc_entry("igmp", net->proc_net); 3178 out_igmp: 3179 return -ENOMEM; 3180 } 3181 3182 static void __net_exit igmp_net_exit(struct net *net) 3183 { 3184 remove_proc_entry("mcfilter", net->proc_net); 3185 remove_proc_entry("igmp", net->proc_net); 3186 inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk); 3187 } 3188 3189 static struct pernet_operations igmp_net_ops = { 3190 .init = igmp_net_init, 3191 .exit = igmp_net_exit, 3192 }; 3193 #endif 3194 3195 static int igmp_netdev_event(struct notifier_block *this, 3196 unsigned long event, void *ptr) 3197 { 3198 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 3199 struct in_device *in_dev; 3200 3201 switch (event) { 3202 case NETDEV_RESEND_IGMP: 3203 in_dev = __in_dev_get_rtnl(dev); 3204 if (in_dev) 3205 ip_mc_rejoin_groups(in_dev); 3206 break; 3207 default: 3208 break; 3209 } 3210 return NOTIFY_DONE; 3211 } 3212 3213 static struct notifier_block igmp_notifier = { 3214 .notifier_call = igmp_netdev_event, 3215 }; 3216 3217 int __init igmp_mc_init(void) 3218 { 3219 #if defined(CONFIG_PROC_FS) 3220 int err; 3221 3222 err = register_pernet_subsys(&igmp_net_ops); 3223 if (err) 3224 return err; 3225 err = register_netdevice_notifier(&igmp_notifier); 3226 if (err) 3227 goto reg_notif_fail; 3228 return 0; 3229 3230 reg_notif_fail: 3231 unregister_pernet_subsys(&igmp_net_ops); 3232 return err; 3233 #else 3234 return register_netdevice_notifier(&igmp_notifier); 3235 #endif 3236 } 3237