1 /* 2 * Linux NET3: Internet Group Management Protocol [IGMP] 3 * 4 * This code implements the IGMP protocol as defined in RFC1112. There has 5 * been a further revision of this protocol since which is now supported. 6 * 7 * If you have trouble with this module be careful what gcc you have used, 8 * the older version didn't come out right using gcc 2.5.8, the newer one 9 * seems to fall out with gcc 2.6.2. 10 * 11 * Authors: 12 * Alan Cox <alan@lxorguk.ukuu.org.uk> 13 * 14 * This program is free software; you can redistribute it and/or 15 * modify it under the terms of the GNU General Public License 16 * as published by the Free Software Foundation; either version 17 * 2 of the License, or (at your option) any later version. 18 * 19 * Fixes: 20 * 21 * Alan Cox : Added lots of __inline__ to optimise 22 * the memory usage of all the tiny little 23 * functions. 24 * Alan Cox : Dumped the header building experiment. 25 * Alan Cox : Minor tweaks ready for multicast routing 26 * and extended IGMP protocol. 27 * Alan Cox : Removed a load of inline directives. Gcc 2.5.8 28 * writes utterly bogus code otherwise (sigh) 29 * fixed IGMP loopback to behave in the manner 30 * desired by mrouted, fixed the fact it has been 31 * broken since 1.3.6 and cleaned up a few minor 32 * points. 33 * 34 * Chih-Jen Chang : Tried to revise IGMP to Version 2 35 * Tsu-Sheng Tsao E-mail: chihjenc@scf.usc.edu and tsusheng@scf.usc.edu 36 * The enhancements are mainly based on Steve Deering's 37 * ipmulti-3.5 source code. 38 * Chih-Jen Chang : Added the igmp_get_mrouter_info and 39 * Tsu-Sheng Tsao igmp_set_mrouter_info to keep track of 40 * the mrouted version on that device. 41 * Chih-Jen Chang : Added the max_resp_time parameter to 42 * Tsu-Sheng Tsao igmp_heard_query(). Using this parameter 43 * to identify the multicast router version 44 * and do what the IGMP version 2 specified. 45 * Chih-Jen Chang : Added a timer to revert to IGMP V2 router 46 * Tsu-Sheng Tsao if the specified time expired. 47 * Alan Cox : Stop IGMP from 0.0.0.0 being accepted. 48 * Alan Cox : Use GFP_ATOMIC in the right places. 49 * Christian Daudt : igmp timer wasn't set for local group 50 * memberships but was being deleted, 51 * which caused a "del_timer() called 52 * from %p with timer not initialized\n" 53 * message (960131). 54 * Christian Daudt : removed del_timer from 55 * igmp_timer_expire function (960205). 56 * Christian Daudt : igmp_heard_report now only calls 57 * igmp_timer_expire if tm->running is 58 * true (960216). 59 * Malcolm Beattie : ttl comparison wrong in igmp_rcv made 60 * igmp_heard_query never trigger. Expiry 61 * miscalculation fixed in igmp_heard_query 62 * and random() made to return unsigned to 63 * prevent negative expiry times. 64 * Alexey Kuznetsov: Wrong group leaving behaviour, backport 65 * fix from pending 2.1.x patches. 66 * Alan Cox: Forget to enable FDDI support earlier. 67 * Alexey Kuznetsov: Fixed leaving groups on device down. 68 * Alexey Kuznetsov: Accordance to igmp-v2-06 draft. 69 * David L Stevens: IGMPv3 support, with help from 70 * Vinay Kulkarni 71 */ 72 73 #include <linux/module.h> 74 #include <linux/slab.h> 75 #include <linux/uaccess.h> 76 #include <linux/types.h> 77 #include <linux/kernel.h> 78 #include <linux/jiffies.h> 79 #include <linux/string.h> 80 #include <linux/socket.h> 81 #include <linux/sockios.h> 82 #include <linux/in.h> 83 #include <linux/inet.h> 84 #include <linux/netdevice.h> 85 #include <linux/skbuff.h> 86 #include <linux/inetdevice.h> 87 #include <linux/igmp.h> 88 #include <linux/if_arp.h> 89 #include <linux/rtnetlink.h> 90 #include <linux/times.h> 91 #include <linux/pkt_sched.h> 92 #include <linux/byteorder/generic.h> 93 94 #include <net/net_namespace.h> 95 #include <net/arp.h> 96 #include <net/ip.h> 97 #include <net/protocol.h> 98 #include <net/route.h> 99 #include <net/sock.h> 100 #include <net/checksum.h> 101 #include <net/inet_common.h> 102 #include <linux/netfilter_ipv4.h> 103 #ifdef CONFIG_IP_MROUTE 104 #include <linux/mroute.h> 105 #endif 106 #ifdef CONFIG_PROC_FS 107 #include <linux/proc_fs.h> 108 #include <linux/seq_file.h> 109 #endif 110 111 #ifdef CONFIG_IP_MULTICAST 112 /* Parameter names and values are taken from igmp-v2-06 draft */ 113 114 #define IGMP_V2_UNSOLICITED_REPORT_INTERVAL (10*HZ) 115 #define IGMP_V3_UNSOLICITED_REPORT_INTERVAL (1*HZ) 116 #define IGMP_QUERY_INTERVAL (125*HZ) 117 #define IGMP_QUERY_RESPONSE_INTERVAL (10*HZ) 118 119 #define IGMP_INITIAL_REPORT_DELAY (1) 120 121 /* IGMP_INITIAL_REPORT_DELAY is not from IGMP specs! 122 * IGMP specs require to report membership immediately after 123 * joining a group, but we delay the first report by a 124 * small interval. It seems more natural and still does not 125 * contradict to specs provided this delay is small enough. 126 */ 127 128 #define IGMP_V1_SEEN(in_dev) \ 129 (IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \ 130 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \ 131 ((in_dev)->mr_v1_seen && \ 132 time_before(jiffies, (in_dev)->mr_v1_seen))) 133 #define IGMP_V2_SEEN(in_dev) \ 134 (IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \ 135 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \ 136 ((in_dev)->mr_v2_seen && \ 137 time_before(jiffies, (in_dev)->mr_v2_seen))) 138 139 static int unsolicited_report_interval(struct in_device *in_dev) 140 { 141 int interval_ms, interval_jiffies; 142 143 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) 144 interval_ms = IN_DEV_CONF_GET( 145 in_dev, 146 IGMPV2_UNSOLICITED_REPORT_INTERVAL); 147 else /* v3 */ 148 interval_ms = IN_DEV_CONF_GET( 149 in_dev, 150 IGMPV3_UNSOLICITED_REPORT_INTERVAL); 151 152 interval_jiffies = msecs_to_jiffies(interval_ms); 153 154 /* _timer functions can't handle a delay of 0 jiffies so ensure 155 * we always return a positive value. 156 */ 157 if (interval_jiffies <= 0) 158 interval_jiffies = 1; 159 return interval_jiffies; 160 } 161 162 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im); 163 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im); 164 static void igmpv3_clear_delrec(struct in_device *in_dev); 165 static int sf_setstate(struct ip_mc_list *pmc); 166 static void sf_markstate(struct ip_mc_list *pmc); 167 #endif 168 static void ip_mc_clear_src(struct ip_mc_list *pmc); 169 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 170 int sfcount, __be32 *psfsrc, int delta); 171 172 static void ip_ma_put(struct ip_mc_list *im) 173 { 174 if (refcount_dec_and_test(&im->refcnt)) { 175 in_dev_put(im->interface); 176 kfree_rcu(im, rcu); 177 } 178 } 179 180 #define for_each_pmc_rcu(in_dev, pmc) \ 181 for (pmc = rcu_dereference(in_dev->mc_list); \ 182 pmc != NULL; \ 183 pmc = rcu_dereference(pmc->next_rcu)) 184 185 #define for_each_pmc_rtnl(in_dev, pmc) \ 186 for (pmc = rtnl_dereference(in_dev->mc_list); \ 187 pmc != NULL; \ 188 pmc = rtnl_dereference(pmc->next_rcu)) 189 190 #ifdef CONFIG_IP_MULTICAST 191 192 /* 193 * Timer management 194 */ 195 196 static void igmp_stop_timer(struct ip_mc_list *im) 197 { 198 spin_lock_bh(&im->lock); 199 if (del_timer(&im->timer)) 200 refcount_dec(&im->refcnt); 201 im->tm_running = 0; 202 im->reporter = 0; 203 im->unsolicit_count = 0; 204 spin_unlock_bh(&im->lock); 205 } 206 207 /* It must be called with locked im->lock */ 208 static void igmp_start_timer(struct ip_mc_list *im, int max_delay) 209 { 210 int tv = prandom_u32() % max_delay; 211 212 im->tm_running = 1; 213 if (!mod_timer(&im->timer, jiffies+tv+2)) 214 refcount_inc(&im->refcnt); 215 } 216 217 static void igmp_gq_start_timer(struct in_device *in_dev) 218 { 219 int tv = prandom_u32() % in_dev->mr_maxdelay; 220 unsigned long exp = jiffies + tv + 2; 221 222 if (in_dev->mr_gq_running && 223 time_after_eq(exp, (in_dev->mr_gq_timer).expires)) 224 return; 225 226 in_dev->mr_gq_running = 1; 227 if (!mod_timer(&in_dev->mr_gq_timer, exp)) 228 in_dev_hold(in_dev); 229 } 230 231 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay) 232 { 233 int tv = prandom_u32() % delay; 234 235 if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2)) 236 in_dev_hold(in_dev); 237 } 238 239 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay) 240 { 241 spin_lock_bh(&im->lock); 242 im->unsolicit_count = 0; 243 if (del_timer(&im->timer)) { 244 if ((long)(im->timer.expires-jiffies) < max_delay) { 245 add_timer(&im->timer); 246 im->tm_running = 1; 247 spin_unlock_bh(&im->lock); 248 return; 249 } 250 refcount_dec(&im->refcnt); 251 } 252 igmp_start_timer(im, max_delay); 253 spin_unlock_bh(&im->lock); 254 } 255 256 257 /* 258 * Send an IGMP report. 259 */ 260 261 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4) 262 263 264 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type, 265 int gdeleted, int sdeleted) 266 { 267 switch (type) { 268 case IGMPV3_MODE_IS_INCLUDE: 269 case IGMPV3_MODE_IS_EXCLUDE: 270 if (gdeleted || sdeleted) 271 return 0; 272 if (!(pmc->gsquery && !psf->sf_gsresp)) { 273 if (pmc->sfmode == MCAST_INCLUDE) 274 return 1; 275 /* don't include if this source is excluded 276 * in all filters 277 */ 278 if (psf->sf_count[MCAST_INCLUDE]) 279 return type == IGMPV3_MODE_IS_INCLUDE; 280 return pmc->sfcount[MCAST_EXCLUDE] == 281 psf->sf_count[MCAST_EXCLUDE]; 282 } 283 return 0; 284 case IGMPV3_CHANGE_TO_INCLUDE: 285 if (gdeleted || sdeleted) 286 return 0; 287 return psf->sf_count[MCAST_INCLUDE] != 0; 288 case IGMPV3_CHANGE_TO_EXCLUDE: 289 if (gdeleted || sdeleted) 290 return 0; 291 if (pmc->sfcount[MCAST_EXCLUDE] == 0 || 292 psf->sf_count[MCAST_INCLUDE]) 293 return 0; 294 return pmc->sfcount[MCAST_EXCLUDE] == 295 psf->sf_count[MCAST_EXCLUDE]; 296 case IGMPV3_ALLOW_NEW_SOURCES: 297 if (gdeleted || !psf->sf_crcount) 298 return 0; 299 return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted; 300 case IGMPV3_BLOCK_OLD_SOURCES: 301 if (pmc->sfmode == MCAST_INCLUDE) 302 return gdeleted || (psf->sf_crcount && sdeleted); 303 return psf->sf_crcount && !gdeleted && !sdeleted; 304 } 305 return 0; 306 } 307 308 static int 309 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted) 310 { 311 struct ip_sf_list *psf; 312 int scount = 0; 313 314 for (psf = pmc->sources; psf; psf = psf->sf_next) { 315 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) 316 continue; 317 scount++; 318 } 319 return scount; 320 } 321 322 /* source address selection per RFC 3376 section 4.2.13 */ 323 static __be32 igmpv3_get_srcaddr(struct net_device *dev, 324 const struct flowi4 *fl4) 325 { 326 struct in_device *in_dev = __in_dev_get_rcu(dev); 327 328 if (!in_dev) 329 return htonl(INADDR_ANY); 330 331 for_ifa(in_dev) { 332 if (fl4->saddr == ifa->ifa_local) 333 return fl4->saddr; 334 } endfor_ifa(in_dev); 335 336 return htonl(INADDR_ANY); 337 } 338 339 static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu) 340 { 341 struct sk_buff *skb; 342 struct rtable *rt; 343 struct iphdr *pip; 344 struct igmpv3_report *pig; 345 struct net *net = dev_net(dev); 346 struct flowi4 fl4; 347 int hlen = LL_RESERVED_SPACE(dev); 348 int tlen = dev->needed_tailroom; 349 unsigned int size = mtu; 350 351 while (1) { 352 skb = alloc_skb(size + hlen + tlen, 353 GFP_ATOMIC | __GFP_NOWARN); 354 if (skb) 355 break; 356 size >>= 1; 357 if (size < 256) 358 return NULL; 359 } 360 skb->priority = TC_PRIO_CONTROL; 361 362 rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0, 363 0, 0, 364 IPPROTO_IGMP, 0, dev->ifindex); 365 if (IS_ERR(rt)) { 366 kfree_skb(skb); 367 return NULL; 368 } 369 370 skb_dst_set(skb, &rt->dst); 371 skb->dev = dev; 372 373 skb_reserve(skb, hlen); 374 skb_tailroom_reserve(skb, mtu, tlen); 375 376 skb_reset_network_header(skb); 377 pip = ip_hdr(skb); 378 skb_put(skb, sizeof(struct iphdr) + 4); 379 380 pip->version = 4; 381 pip->ihl = (sizeof(struct iphdr)+4)>>2; 382 pip->tos = 0xc0; 383 pip->frag_off = htons(IP_DF); 384 pip->ttl = 1; 385 pip->daddr = fl4.daddr; 386 387 rcu_read_lock(); 388 pip->saddr = igmpv3_get_srcaddr(dev, &fl4); 389 rcu_read_unlock(); 390 391 pip->protocol = IPPROTO_IGMP; 392 pip->tot_len = 0; /* filled in later */ 393 ip_select_ident(net, skb, NULL); 394 ((u8 *)&pip[1])[0] = IPOPT_RA; 395 ((u8 *)&pip[1])[1] = 4; 396 ((u8 *)&pip[1])[2] = 0; 397 ((u8 *)&pip[1])[3] = 0; 398 399 skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4; 400 skb_put(skb, sizeof(*pig)); 401 pig = igmpv3_report_hdr(skb); 402 pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT; 403 pig->resv1 = 0; 404 pig->csum = 0; 405 pig->resv2 = 0; 406 pig->ngrec = 0; 407 return skb; 408 } 409 410 static int igmpv3_sendpack(struct sk_buff *skb) 411 { 412 struct igmphdr *pig = igmp_hdr(skb); 413 const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb); 414 415 pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen); 416 417 return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb); 418 } 419 420 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel) 421 { 422 return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel); 423 } 424 425 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc, 426 int type, struct igmpv3_grec **ppgr, unsigned int mtu) 427 { 428 struct net_device *dev = pmc->interface->dev; 429 struct igmpv3_report *pih; 430 struct igmpv3_grec *pgr; 431 432 if (!skb) { 433 skb = igmpv3_newpack(dev, mtu); 434 if (!skb) 435 return NULL; 436 } 437 pgr = skb_put(skb, sizeof(struct igmpv3_grec)); 438 pgr->grec_type = type; 439 pgr->grec_auxwords = 0; 440 pgr->grec_nsrcs = 0; 441 pgr->grec_mca = pmc->multiaddr; 442 pih = igmpv3_report_hdr(skb); 443 pih->ngrec = htons(ntohs(pih->ngrec)+1); 444 *ppgr = pgr; 445 return skb; 446 } 447 448 #define AVAILABLE(skb) ((skb) ? skb_availroom(skb) : 0) 449 450 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc, 451 int type, int gdeleted, int sdeleted) 452 { 453 struct net_device *dev = pmc->interface->dev; 454 struct net *net = dev_net(dev); 455 struct igmpv3_report *pih; 456 struct igmpv3_grec *pgr = NULL; 457 struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list; 458 int scount, stotal, first, isquery, truncate; 459 unsigned int mtu; 460 461 if (pmc->multiaddr == IGMP_ALL_HOSTS) 462 return skb; 463 if (ipv4_is_local_multicast(pmc->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports) 464 return skb; 465 466 mtu = READ_ONCE(dev->mtu); 467 if (mtu < IPV4_MIN_MTU) 468 return skb; 469 470 isquery = type == IGMPV3_MODE_IS_INCLUDE || 471 type == IGMPV3_MODE_IS_EXCLUDE; 472 truncate = type == IGMPV3_MODE_IS_EXCLUDE || 473 type == IGMPV3_CHANGE_TO_EXCLUDE; 474 475 stotal = scount = 0; 476 477 psf_list = sdeleted ? &pmc->tomb : &pmc->sources; 478 479 if (!*psf_list) 480 goto empty_source; 481 482 pih = skb ? igmpv3_report_hdr(skb) : NULL; 483 484 /* EX and TO_EX get a fresh packet, if needed */ 485 if (truncate) { 486 if (pih && pih->ngrec && 487 AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) { 488 if (skb) 489 igmpv3_sendpack(skb); 490 skb = igmpv3_newpack(dev, mtu); 491 } 492 } 493 first = 1; 494 psf_prev = NULL; 495 for (psf = *psf_list; psf; psf = psf_next) { 496 __be32 *psrc; 497 498 psf_next = psf->sf_next; 499 500 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) { 501 psf_prev = psf; 502 continue; 503 } 504 505 /* Based on RFC3376 5.1. Should not send source-list change 506 * records when there is a filter mode change. 507 */ 508 if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) || 509 (!gdeleted && pmc->crcount)) && 510 (type == IGMPV3_ALLOW_NEW_SOURCES || 511 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) 512 goto decrease_sf_crcount; 513 514 /* clear marks on query responses */ 515 if (isquery) 516 psf->sf_gsresp = 0; 517 518 if (AVAILABLE(skb) < sizeof(__be32) + 519 first*sizeof(struct igmpv3_grec)) { 520 if (truncate && !first) 521 break; /* truncate these */ 522 if (pgr) 523 pgr->grec_nsrcs = htons(scount); 524 if (skb) 525 igmpv3_sendpack(skb); 526 skb = igmpv3_newpack(dev, mtu); 527 first = 1; 528 scount = 0; 529 } 530 if (first) { 531 skb = add_grhead(skb, pmc, type, &pgr, mtu); 532 first = 0; 533 } 534 if (!skb) 535 return NULL; 536 psrc = skb_put(skb, sizeof(__be32)); 537 *psrc = psf->sf_inaddr; 538 scount++; stotal++; 539 if ((type == IGMPV3_ALLOW_NEW_SOURCES || 540 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) { 541 decrease_sf_crcount: 542 psf->sf_crcount--; 543 if ((sdeleted || gdeleted) && psf->sf_crcount == 0) { 544 if (psf_prev) 545 psf_prev->sf_next = psf->sf_next; 546 else 547 *psf_list = psf->sf_next; 548 kfree(psf); 549 continue; 550 } 551 } 552 psf_prev = psf; 553 } 554 555 empty_source: 556 if (!stotal) { 557 if (type == IGMPV3_ALLOW_NEW_SOURCES || 558 type == IGMPV3_BLOCK_OLD_SOURCES) 559 return skb; 560 if (pmc->crcount || isquery) { 561 /* make sure we have room for group header */ 562 if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) { 563 igmpv3_sendpack(skb); 564 skb = NULL; /* add_grhead will get a new one */ 565 } 566 skb = add_grhead(skb, pmc, type, &pgr, mtu); 567 } 568 } 569 if (pgr) 570 pgr->grec_nsrcs = htons(scount); 571 572 if (isquery) 573 pmc->gsquery = 0; /* clear query state on report */ 574 return skb; 575 } 576 577 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc) 578 { 579 struct sk_buff *skb = NULL; 580 struct net *net = dev_net(in_dev->dev); 581 int type; 582 583 if (!pmc) { 584 rcu_read_lock(); 585 for_each_pmc_rcu(in_dev, pmc) { 586 if (pmc->multiaddr == IGMP_ALL_HOSTS) 587 continue; 588 if (ipv4_is_local_multicast(pmc->multiaddr) && 589 !net->ipv4.sysctl_igmp_llm_reports) 590 continue; 591 spin_lock_bh(&pmc->lock); 592 if (pmc->sfcount[MCAST_EXCLUDE]) 593 type = IGMPV3_MODE_IS_EXCLUDE; 594 else 595 type = IGMPV3_MODE_IS_INCLUDE; 596 skb = add_grec(skb, pmc, type, 0, 0); 597 spin_unlock_bh(&pmc->lock); 598 } 599 rcu_read_unlock(); 600 } else { 601 spin_lock_bh(&pmc->lock); 602 if (pmc->sfcount[MCAST_EXCLUDE]) 603 type = IGMPV3_MODE_IS_EXCLUDE; 604 else 605 type = IGMPV3_MODE_IS_INCLUDE; 606 skb = add_grec(skb, pmc, type, 0, 0); 607 spin_unlock_bh(&pmc->lock); 608 } 609 if (!skb) 610 return 0; 611 return igmpv3_sendpack(skb); 612 } 613 614 /* 615 * remove zero-count source records from a source filter list 616 */ 617 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf) 618 { 619 struct ip_sf_list *psf_prev, *psf_next, *psf; 620 621 psf_prev = NULL; 622 for (psf = *ppsf; psf; psf = psf_next) { 623 psf_next = psf->sf_next; 624 if (psf->sf_crcount == 0) { 625 if (psf_prev) 626 psf_prev->sf_next = psf->sf_next; 627 else 628 *ppsf = psf->sf_next; 629 kfree(psf); 630 } else 631 psf_prev = psf; 632 } 633 } 634 635 static void igmpv3_send_cr(struct in_device *in_dev) 636 { 637 struct ip_mc_list *pmc, *pmc_prev, *pmc_next; 638 struct sk_buff *skb = NULL; 639 int type, dtype; 640 641 rcu_read_lock(); 642 spin_lock_bh(&in_dev->mc_tomb_lock); 643 644 /* deleted MCA's */ 645 pmc_prev = NULL; 646 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) { 647 pmc_next = pmc->next; 648 if (pmc->sfmode == MCAST_INCLUDE) { 649 type = IGMPV3_BLOCK_OLD_SOURCES; 650 dtype = IGMPV3_BLOCK_OLD_SOURCES; 651 skb = add_grec(skb, pmc, type, 1, 0); 652 skb = add_grec(skb, pmc, dtype, 1, 1); 653 } 654 if (pmc->crcount) { 655 if (pmc->sfmode == MCAST_EXCLUDE) { 656 type = IGMPV3_CHANGE_TO_INCLUDE; 657 skb = add_grec(skb, pmc, type, 1, 0); 658 } 659 pmc->crcount--; 660 if (pmc->crcount == 0) { 661 igmpv3_clear_zeros(&pmc->tomb); 662 igmpv3_clear_zeros(&pmc->sources); 663 } 664 } 665 if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) { 666 if (pmc_prev) 667 pmc_prev->next = pmc_next; 668 else 669 in_dev->mc_tomb = pmc_next; 670 in_dev_put(pmc->interface); 671 kfree(pmc); 672 } else 673 pmc_prev = pmc; 674 } 675 spin_unlock_bh(&in_dev->mc_tomb_lock); 676 677 /* change recs */ 678 for_each_pmc_rcu(in_dev, pmc) { 679 spin_lock_bh(&pmc->lock); 680 if (pmc->sfcount[MCAST_EXCLUDE]) { 681 type = IGMPV3_BLOCK_OLD_SOURCES; 682 dtype = IGMPV3_ALLOW_NEW_SOURCES; 683 } else { 684 type = IGMPV3_ALLOW_NEW_SOURCES; 685 dtype = IGMPV3_BLOCK_OLD_SOURCES; 686 } 687 skb = add_grec(skb, pmc, type, 0, 0); 688 skb = add_grec(skb, pmc, dtype, 0, 1); /* deleted sources */ 689 690 /* filter mode changes */ 691 if (pmc->crcount) { 692 if (pmc->sfmode == MCAST_EXCLUDE) 693 type = IGMPV3_CHANGE_TO_EXCLUDE; 694 else 695 type = IGMPV3_CHANGE_TO_INCLUDE; 696 skb = add_grec(skb, pmc, type, 0, 0); 697 pmc->crcount--; 698 } 699 spin_unlock_bh(&pmc->lock); 700 } 701 rcu_read_unlock(); 702 703 if (!skb) 704 return; 705 (void) igmpv3_sendpack(skb); 706 } 707 708 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc, 709 int type) 710 { 711 struct sk_buff *skb; 712 struct iphdr *iph; 713 struct igmphdr *ih; 714 struct rtable *rt; 715 struct net_device *dev = in_dev->dev; 716 struct net *net = dev_net(dev); 717 __be32 group = pmc ? pmc->multiaddr : 0; 718 struct flowi4 fl4; 719 __be32 dst; 720 int hlen, tlen; 721 722 if (type == IGMPV3_HOST_MEMBERSHIP_REPORT) 723 return igmpv3_send_report(in_dev, pmc); 724 725 if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports) 726 return 0; 727 728 if (type == IGMP_HOST_LEAVE_MESSAGE) 729 dst = IGMP_ALL_ROUTER; 730 else 731 dst = group; 732 733 rt = ip_route_output_ports(net, &fl4, NULL, dst, 0, 734 0, 0, 735 IPPROTO_IGMP, 0, dev->ifindex); 736 if (IS_ERR(rt)) 737 return -1; 738 739 hlen = LL_RESERVED_SPACE(dev); 740 tlen = dev->needed_tailroom; 741 skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC); 742 if (!skb) { 743 ip_rt_put(rt); 744 return -1; 745 } 746 skb->priority = TC_PRIO_CONTROL; 747 748 skb_dst_set(skb, &rt->dst); 749 750 skb_reserve(skb, hlen); 751 752 skb_reset_network_header(skb); 753 iph = ip_hdr(skb); 754 skb_put(skb, sizeof(struct iphdr) + 4); 755 756 iph->version = 4; 757 iph->ihl = (sizeof(struct iphdr)+4)>>2; 758 iph->tos = 0xc0; 759 iph->frag_off = htons(IP_DF); 760 iph->ttl = 1; 761 iph->daddr = dst; 762 iph->saddr = fl4.saddr; 763 iph->protocol = IPPROTO_IGMP; 764 ip_select_ident(net, skb, NULL); 765 ((u8 *)&iph[1])[0] = IPOPT_RA; 766 ((u8 *)&iph[1])[1] = 4; 767 ((u8 *)&iph[1])[2] = 0; 768 ((u8 *)&iph[1])[3] = 0; 769 770 ih = skb_put(skb, sizeof(struct igmphdr)); 771 ih->type = type; 772 ih->code = 0; 773 ih->csum = 0; 774 ih->group = group; 775 ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr)); 776 777 return ip_local_out(net, skb->sk, skb); 778 } 779 780 static void igmp_gq_timer_expire(struct timer_list *t) 781 { 782 struct in_device *in_dev = from_timer(in_dev, t, mr_gq_timer); 783 784 in_dev->mr_gq_running = 0; 785 igmpv3_send_report(in_dev, NULL); 786 in_dev_put(in_dev); 787 } 788 789 static void igmp_ifc_timer_expire(struct timer_list *t) 790 { 791 struct in_device *in_dev = from_timer(in_dev, t, mr_ifc_timer); 792 793 igmpv3_send_cr(in_dev); 794 if (in_dev->mr_ifc_count) { 795 in_dev->mr_ifc_count--; 796 igmp_ifc_start_timer(in_dev, 797 unsolicited_report_interval(in_dev)); 798 } 799 in_dev_put(in_dev); 800 } 801 802 static void igmp_ifc_event(struct in_device *in_dev) 803 { 804 struct net *net = dev_net(in_dev->dev); 805 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) 806 return; 807 in_dev->mr_ifc_count = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 808 igmp_ifc_start_timer(in_dev, 1); 809 } 810 811 812 static void igmp_timer_expire(struct timer_list *t) 813 { 814 struct ip_mc_list *im = from_timer(im, t, timer); 815 struct in_device *in_dev = im->interface; 816 817 spin_lock(&im->lock); 818 im->tm_running = 0; 819 820 if (im->unsolicit_count && --im->unsolicit_count) 821 igmp_start_timer(im, unsolicited_report_interval(in_dev)); 822 823 im->reporter = 1; 824 spin_unlock(&im->lock); 825 826 if (IGMP_V1_SEEN(in_dev)) 827 igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT); 828 else if (IGMP_V2_SEEN(in_dev)) 829 igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT); 830 else 831 igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT); 832 833 ip_ma_put(im); 834 } 835 836 /* mark EXCLUDE-mode sources */ 837 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs) 838 { 839 struct ip_sf_list *psf; 840 int i, scount; 841 842 scount = 0; 843 for (psf = pmc->sources; psf; psf = psf->sf_next) { 844 if (scount == nsrcs) 845 break; 846 for (i = 0; i < nsrcs; i++) { 847 /* skip inactive filters */ 848 if (psf->sf_count[MCAST_INCLUDE] || 849 pmc->sfcount[MCAST_EXCLUDE] != 850 psf->sf_count[MCAST_EXCLUDE]) 851 break; 852 if (srcs[i] == psf->sf_inaddr) { 853 scount++; 854 break; 855 } 856 } 857 } 858 pmc->gsquery = 0; 859 if (scount == nsrcs) /* all sources excluded */ 860 return 0; 861 return 1; 862 } 863 864 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs) 865 { 866 struct ip_sf_list *psf; 867 int i, scount; 868 869 if (pmc->sfmode == MCAST_EXCLUDE) 870 return igmp_xmarksources(pmc, nsrcs, srcs); 871 872 /* mark INCLUDE-mode sources */ 873 scount = 0; 874 for (psf = pmc->sources; psf; psf = psf->sf_next) { 875 if (scount == nsrcs) 876 break; 877 for (i = 0; i < nsrcs; i++) 878 if (srcs[i] == psf->sf_inaddr) { 879 psf->sf_gsresp = 1; 880 scount++; 881 break; 882 } 883 } 884 if (!scount) { 885 pmc->gsquery = 0; 886 return 0; 887 } 888 pmc->gsquery = 1; 889 return 1; 890 } 891 892 /* return true if packet was dropped */ 893 static bool igmp_heard_report(struct in_device *in_dev, __be32 group) 894 { 895 struct ip_mc_list *im; 896 struct net *net = dev_net(in_dev->dev); 897 898 /* Timers are only set for non-local groups */ 899 900 if (group == IGMP_ALL_HOSTS) 901 return false; 902 if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports) 903 return false; 904 905 rcu_read_lock(); 906 for_each_pmc_rcu(in_dev, im) { 907 if (im->multiaddr == group) { 908 igmp_stop_timer(im); 909 break; 910 } 911 } 912 rcu_read_unlock(); 913 return false; 914 } 915 916 /* return true if packet was dropped */ 917 static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb, 918 int len) 919 { 920 struct igmphdr *ih = igmp_hdr(skb); 921 struct igmpv3_query *ih3 = igmpv3_query_hdr(skb); 922 struct ip_mc_list *im; 923 __be32 group = ih->group; 924 int max_delay; 925 int mark = 0; 926 struct net *net = dev_net(in_dev->dev); 927 928 929 if (len == 8) { 930 if (ih->code == 0) { 931 /* Alas, old v1 router presents here. */ 932 933 max_delay = IGMP_QUERY_RESPONSE_INTERVAL; 934 in_dev->mr_v1_seen = jiffies + 935 (in_dev->mr_qrv * in_dev->mr_qi) + 936 in_dev->mr_qri; 937 group = 0; 938 } else { 939 /* v2 router present */ 940 max_delay = ih->code*(HZ/IGMP_TIMER_SCALE); 941 in_dev->mr_v2_seen = jiffies + 942 (in_dev->mr_qrv * in_dev->mr_qi) + 943 in_dev->mr_qri; 944 } 945 /* cancel the interface change timer */ 946 in_dev->mr_ifc_count = 0; 947 if (del_timer(&in_dev->mr_ifc_timer)) 948 __in_dev_put(in_dev); 949 /* clear deleted report items */ 950 igmpv3_clear_delrec(in_dev); 951 } else if (len < 12) { 952 return true; /* ignore bogus packet; freed by caller */ 953 } else if (IGMP_V1_SEEN(in_dev)) { 954 /* This is a v3 query with v1 queriers present */ 955 max_delay = IGMP_QUERY_RESPONSE_INTERVAL; 956 group = 0; 957 } else if (IGMP_V2_SEEN(in_dev)) { 958 /* this is a v3 query with v2 queriers present; 959 * Interpretation of the max_delay code is problematic here. 960 * A real v2 host would use ih_code directly, while v3 has a 961 * different encoding. We use the v3 encoding as more likely 962 * to be intended in a v3 query. 963 */ 964 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE); 965 if (!max_delay) 966 max_delay = 1; /* can't mod w/ 0 */ 967 } else { /* v3 */ 968 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) 969 return true; 970 971 ih3 = igmpv3_query_hdr(skb); 972 if (ih3->nsrcs) { 973 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query) 974 + ntohs(ih3->nsrcs)*sizeof(__be32))) 975 return true; 976 ih3 = igmpv3_query_hdr(skb); 977 } 978 979 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE); 980 if (!max_delay) 981 max_delay = 1; /* can't mod w/ 0 */ 982 in_dev->mr_maxdelay = max_delay; 983 984 /* RFC3376, 4.1.6. QRV and 4.1.7. QQIC, when the most recently 985 * received value was zero, use the default or statically 986 * configured value. 987 */ 988 in_dev->mr_qrv = ih3->qrv ?: net->ipv4.sysctl_igmp_qrv; 989 in_dev->mr_qi = IGMPV3_QQIC(ih3->qqic)*HZ ?: IGMP_QUERY_INTERVAL; 990 991 /* RFC3376, 8.3. Query Response Interval: 992 * The number of seconds represented by the [Query Response 993 * Interval] must be less than the [Query Interval]. 994 */ 995 if (in_dev->mr_qri >= in_dev->mr_qi) 996 in_dev->mr_qri = (in_dev->mr_qi/HZ - 1)*HZ; 997 998 if (!group) { /* general query */ 999 if (ih3->nsrcs) 1000 return true; /* no sources allowed */ 1001 igmp_gq_start_timer(in_dev); 1002 return false; 1003 } 1004 /* mark sources to include, if group & source-specific */ 1005 mark = ih3->nsrcs != 0; 1006 } 1007 1008 /* 1009 * - Start the timers in all of our membership records 1010 * that the query applies to for the interface on 1011 * which the query arrived excl. those that belong 1012 * to a "local" group (224.0.0.X) 1013 * - For timers already running check if they need to 1014 * be reset. 1015 * - Use the igmp->igmp_code field as the maximum 1016 * delay possible 1017 */ 1018 rcu_read_lock(); 1019 for_each_pmc_rcu(in_dev, im) { 1020 int changed; 1021 1022 if (group && group != im->multiaddr) 1023 continue; 1024 if (im->multiaddr == IGMP_ALL_HOSTS) 1025 continue; 1026 if (ipv4_is_local_multicast(im->multiaddr) && 1027 !net->ipv4.sysctl_igmp_llm_reports) 1028 continue; 1029 spin_lock_bh(&im->lock); 1030 if (im->tm_running) 1031 im->gsquery = im->gsquery && mark; 1032 else 1033 im->gsquery = mark; 1034 changed = !im->gsquery || 1035 igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs); 1036 spin_unlock_bh(&im->lock); 1037 if (changed) 1038 igmp_mod_timer(im, max_delay); 1039 } 1040 rcu_read_unlock(); 1041 return false; 1042 } 1043 1044 /* called in rcu_read_lock() section */ 1045 int igmp_rcv(struct sk_buff *skb) 1046 { 1047 /* This basically follows the spec line by line -- see RFC1112 */ 1048 struct igmphdr *ih; 1049 struct net_device *dev = skb->dev; 1050 struct in_device *in_dev; 1051 int len = skb->len; 1052 bool dropped = true; 1053 1054 if (netif_is_l3_master(dev)) { 1055 dev = dev_get_by_index_rcu(dev_net(dev), IPCB(skb)->iif); 1056 if (!dev) 1057 goto drop; 1058 } 1059 1060 in_dev = __in_dev_get_rcu(dev); 1061 if (!in_dev) 1062 goto drop; 1063 1064 if (!pskb_may_pull(skb, sizeof(struct igmphdr))) 1065 goto drop; 1066 1067 if (skb_checksum_simple_validate(skb)) 1068 goto drop; 1069 1070 ih = igmp_hdr(skb); 1071 switch (ih->type) { 1072 case IGMP_HOST_MEMBERSHIP_QUERY: 1073 dropped = igmp_heard_query(in_dev, skb, len); 1074 break; 1075 case IGMP_HOST_MEMBERSHIP_REPORT: 1076 case IGMPV2_HOST_MEMBERSHIP_REPORT: 1077 /* Is it our report looped back? */ 1078 if (rt_is_output_route(skb_rtable(skb))) 1079 break; 1080 /* don't rely on MC router hearing unicast reports */ 1081 if (skb->pkt_type == PACKET_MULTICAST || 1082 skb->pkt_type == PACKET_BROADCAST) 1083 dropped = igmp_heard_report(in_dev, ih->group); 1084 break; 1085 case IGMP_PIM: 1086 #ifdef CONFIG_IP_PIMSM_V1 1087 return pim_rcv_v1(skb); 1088 #endif 1089 case IGMPV3_HOST_MEMBERSHIP_REPORT: 1090 case IGMP_DVMRP: 1091 case IGMP_TRACE: 1092 case IGMP_HOST_LEAVE_MESSAGE: 1093 case IGMP_MTRACE: 1094 case IGMP_MTRACE_RESP: 1095 break; 1096 default: 1097 break; 1098 } 1099 1100 drop: 1101 if (dropped) 1102 kfree_skb(skb); 1103 else 1104 consume_skb(skb); 1105 return 0; 1106 } 1107 1108 #endif 1109 1110 1111 /* 1112 * Add a filter to a device 1113 */ 1114 1115 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr) 1116 { 1117 char buf[MAX_ADDR_LEN]; 1118 struct net_device *dev = in_dev->dev; 1119 1120 /* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG. 1121 We will get multicast token leakage, when IFF_MULTICAST 1122 is changed. This check should be done in ndo_set_rx_mode 1123 routine. Something sort of: 1124 if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; } 1125 --ANK 1126 */ 1127 if (arp_mc_map(addr, buf, dev, 0) == 0) 1128 dev_mc_add(dev, buf); 1129 } 1130 1131 /* 1132 * Remove a filter from a device 1133 */ 1134 1135 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr) 1136 { 1137 char buf[MAX_ADDR_LEN]; 1138 struct net_device *dev = in_dev->dev; 1139 1140 if (arp_mc_map(addr, buf, dev, 0) == 0) 1141 dev_mc_del(dev, buf); 1142 } 1143 1144 #ifdef CONFIG_IP_MULTICAST 1145 /* 1146 * deleted ip_mc_list manipulation 1147 */ 1148 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im) 1149 { 1150 struct ip_mc_list *pmc; 1151 struct net *net = dev_net(in_dev->dev); 1152 1153 /* this is an "ip_mc_list" for convenience; only the fields below 1154 * are actually used. In particular, the refcnt and users are not 1155 * used for management of the delete list. Using the same structure 1156 * for deleted items allows change reports to use common code with 1157 * non-deleted or query-response MCA's. 1158 */ 1159 pmc = kzalloc(sizeof(*pmc), GFP_KERNEL); 1160 if (!pmc) 1161 return; 1162 spin_lock_init(&pmc->lock); 1163 spin_lock_bh(&im->lock); 1164 pmc->interface = im->interface; 1165 in_dev_hold(in_dev); 1166 pmc->multiaddr = im->multiaddr; 1167 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1168 pmc->sfmode = im->sfmode; 1169 if (pmc->sfmode == MCAST_INCLUDE) { 1170 struct ip_sf_list *psf; 1171 1172 pmc->tomb = im->tomb; 1173 pmc->sources = im->sources; 1174 im->tomb = im->sources = NULL; 1175 for (psf = pmc->sources; psf; psf = psf->sf_next) 1176 psf->sf_crcount = pmc->crcount; 1177 } 1178 spin_unlock_bh(&im->lock); 1179 1180 spin_lock_bh(&in_dev->mc_tomb_lock); 1181 pmc->next = in_dev->mc_tomb; 1182 in_dev->mc_tomb = pmc; 1183 spin_unlock_bh(&in_dev->mc_tomb_lock); 1184 } 1185 1186 /* 1187 * restore ip_mc_list deleted records 1188 */ 1189 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im) 1190 { 1191 struct ip_mc_list *pmc, *pmc_prev; 1192 struct ip_sf_list *psf; 1193 struct net *net = dev_net(in_dev->dev); 1194 __be32 multiaddr = im->multiaddr; 1195 1196 spin_lock_bh(&in_dev->mc_tomb_lock); 1197 pmc_prev = NULL; 1198 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) { 1199 if (pmc->multiaddr == multiaddr) 1200 break; 1201 pmc_prev = pmc; 1202 } 1203 if (pmc) { 1204 if (pmc_prev) 1205 pmc_prev->next = pmc->next; 1206 else 1207 in_dev->mc_tomb = pmc->next; 1208 } 1209 spin_unlock_bh(&in_dev->mc_tomb_lock); 1210 1211 spin_lock_bh(&im->lock); 1212 if (pmc) { 1213 im->interface = pmc->interface; 1214 if (im->sfmode == MCAST_INCLUDE) { 1215 im->tomb = pmc->tomb; 1216 im->sources = pmc->sources; 1217 for (psf = im->sources; psf; psf = psf->sf_next) 1218 psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1219 } else { 1220 im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1221 } 1222 in_dev_put(pmc->interface); 1223 kfree(pmc); 1224 } 1225 spin_unlock_bh(&im->lock); 1226 } 1227 1228 /* 1229 * flush ip_mc_list deleted records 1230 */ 1231 static void igmpv3_clear_delrec(struct in_device *in_dev) 1232 { 1233 struct ip_mc_list *pmc, *nextpmc; 1234 1235 spin_lock_bh(&in_dev->mc_tomb_lock); 1236 pmc = in_dev->mc_tomb; 1237 in_dev->mc_tomb = NULL; 1238 spin_unlock_bh(&in_dev->mc_tomb_lock); 1239 1240 for (; pmc; pmc = nextpmc) { 1241 nextpmc = pmc->next; 1242 ip_mc_clear_src(pmc); 1243 in_dev_put(pmc->interface); 1244 kfree(pmc); 1245 } 1246 /* clear dead sources, too */ 1247 rcu_read_lock(); 1248 for_each_pmc_rcu(in_dev, pmc) { 1249 struct ip_sf_list *psf, *psf_next; 1250 1251 spin_lock_bh(&pmc->lock); 1252 psf = pmc->tomb; 1253 pmc->tomb = NULL; 1254 spin_unlock_bh(&pmc->lock); 1255 for (; psf; psf = psf_next) { 1256 psf_next = psf->sf_next; 1257 kfree(psf); 1258 } 1259 } 1260 rcu_read_unlock(); 1261 } 1262 #endif 1263 1264 static void igmp_group_dropped(struct ip_mc_list *im) 1265 { 1266 struct in_device *in_dev = im->interface; 1267 #ifdef CONFIG_IP_MULTICAST 1268 struct net *net = dev_net(in_dev->dev); 1269 int reporter; 1270 #endif 1271 1272 if (im->loaded) { 1273 im->loaded = 0; 1274 ip_mc_filter_del(in_dev, im->multiaddr); 1275 } 1276 1277 #ifdef CONFIG_IP_MULTICAST 1278 if (im->multiaddr == IGMP_ALL_HOSTS) 1279 return; 1280 if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports) 1281 return; 1282 1283 reporter = im->reporter; 1284 igmp_stop_timer(im); 1285 1286 if (!in_dev->dead) { 1287 if (IGMP_V1_SEEN(in_dev)) 1288 return; 1289 if (IGMP_V2_SEEN(in_dev)) { 1290 if (reporter) 1291 igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE); 1292 return; 1293 } 1294 /* IGMPv3 */ 1295 igmpv3_add_delrec(in_dev, im); 1296 1297 igmp_ifc_event(in_dev); 1298 } 1299 #endif 1300 } 1301 1302 static void igmp_group_added(struct ip_mc_list *im) 1303 { 1304 struct in_device *in_dev = im->interface; 1305 #ifdef CONFIG_IP_MULTICAST 1306 struct net *net = dev_net(in_dev->dev); 1307 #endif 1308 1309 if (im->loaded == 0) { 1310 im->loaded = 1; 1311 ip_mc_filter_add(in_dev, im->multiaddr); 1312 } 1313 1314 #ifdef CONFIG_IP_MULTICAST 1315 if (im->multiaddr == IGMP_ALL_HOSTS) 1316 return; 1317 if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports) 1318 return; 1319 1320 if (in_dev->dead) 1321 return; 1322 1323 im->unsolicit_count = net->ipv4.sysctl_igmp_qrv; 1324 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) { 1325 spin_lock_bh(&im->lock); 1326 igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY); 1327 spin_unlock_bh(&im->lock); 1328 return; 1329 } 1330 /* else, v3 */ 1331 1332 /* Based on RFC3376 5.1, for newly added INCLUDE SSM, we should 1333 * not send filter-mode change record as the mode should be from 1334 * IN() to IN(A). 1335 */ 1336 if (im->sfmode == MCAST_EXCLUDE) 1337 im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1338 1339 igmp_ifc_event(in_dev); 1340 #endif 1341 } 1342 1343 1344 /* 1345 * Multicast list managers 1346 */ 1347 1348 static u32 ip_mc_hash(const struct ip_mc_list *im) 1349 { 1350 return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG); 1351 } 1352 1353 static void ip_mc_hash_add(struct in_device *in_dev, 1354 struct ip_mc_list *im) 1355 { 1356 struct ip_mc_list __rcu **mc_hash; 1357 u32 hash; 1358 1359 mc_hash = rtnl_dereference(in_dev->mc_hash); 1360 if (mc_hash) { 1361 hash = ip_mc_hash(im); 1362 im->next_hash = mc_hash[hash]; 1363 rcu_assign_pointer(mc_hash[hash], im); 1364 return; 1365 } 1366 1367 /* do not use a hash table for small number of items */ 1368 if (in_dev->mc_count < 4) 1369 return; 1370 1371 mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG, 1372 GFP_KERNEL); 1373 if (!mc_hash) 1374 return; 1375 1376 for_each_pmc_rtnl(in_dev, im) { 1377 hash = ip_mc_hash(im); 1378 im->next_hash = mc_hash[hash]; 1379 RCU_INIT_POINTER(mc_hash[hash], im); 1380 } 1381 1382 rcu_assign_pointer(in_dev->mc_hash, mc_hash); 1383 } 1384 1385 static void ip_mc_hash_remove(struct in_device *in_dev, 1386 struct ip_mc_list *im) 1387 { 1388 struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash); 1389 struct ip_mc_list *aux; 1390 1391 if (!mc_hash) 1392 return; 1393 mc_hash += ip_mc_hash(im); 1394 while ((aux = rtnl_dereference(*mc_hash)) != im) 1395 mc_hash = &aux->next_hash; 1396 *mc_hash = im->next_hash; 1397 } 1398 1399 1400 /* 1401 * A socket has joined a multicast group on device dev. 1402 */ 1403 static void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr, 1404 unsigned int mode) 1405 { 1406 struct ip_mc_list *im; 1407 1408 ASSERT_RTNL(); 1409 1410 for_each_pmc_rtnl(in_dev, im) { 1411 if (im->multiaddr == addr) { 1412 im->users++; 1413 ip_mc_add_src(in_dev, &addr, mode, 0, NULL, 0); 1414 goto out; 1415 } 1416 } 1417 1418 im = kzalloc(sizeof(*im), GFP_KERNEL); 1419 if (!im) 1420 goto out; 1421 1422 im->users = 1; 1423 im->interface = in_dev; 1424 in_dev_hold(in_dev); 1425 im->multiaddr = addr; 1426 /* initial mode is (EX, empty) */ 1427 im->sfmode = mode; 1428 im->sfcount[mode] = 1; 1429 refcount_set(&im->refcnt, 1); 1430 spin_lock_init(&im->lock); 1431 #ifdef CONFIG_IP_MULTICAST 1432 timer_setup(&im->timer, igmp_timer_expire, 0); 1433 #endif 1434 1435 im->next_rcu = in_dev->mc_list; 1436 in_dev->mc_count++; 1437 rcu_assign_pointer(in_dev->mc_list, im); 1438 1439 ip_mc_hash_add(in_dev, im); 1440 1441 #ifdef CONFIG_IP_MULTICAST 1442 igmpv3_del_delrec(in_dev, im); 1443 #endif 1444 igmp_group_added(im); 1445 if (!in_dev->dead) 1446 ip_rt_multicast_event(in_dev); 1447 out: 1448 return; 1449 } 1450 1451 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr) 1452 { 1453 __ip_mc_inc_group(in_dev, addr, MCAST_EXCLUDE); 1454 } 1455 EXPORT_SYMBOL(ip_mc_inc_group); 1456 1457 static int ip_mc_check_iphdr(struct sk_buff *skb) 1458 { 1459 const struct iphdr *iph; 1460 unsigned int len; 1461 unsigned int offset = skb_network_offset(skb) + sizeof(*iph); 1462 1463 if (!pskb_may_pull(skb, offset)) 1464 return -EINVAL; 1465 1466 iph = ip_hdr(skb); 1467 1468 if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph)) 1469 return -EINVAL; 1470 1471 offset += ip_hdrlen(skb) - sizeof(*iph); 1472 1473 if (!pskb_may_pull(skb, offset)) 1474 return -EINVAL; 1475 1476 iph = ip_hdr(skb); 1477 1478 if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl))) 1479 return -EINVAL; 1480 1481 len = skb_network_offset(skb) + ntohs(iph->tot_len); 1482 if (skb->len < len || len < offset) 1483 return -EINVAL; 1484 1485 skb_set_transport_header(skb, offset); 1486 1487 return 0; 1488 } 1489 1490 static int ip_mc_check_igmp_reportv3(struct sk_buff *skb) 1491 { 1492 unsigned int len = skb_transport_offset(skb); 1493 1494 len += sizeof(struct igmpv3_report); 1495 1496 return ip_mc_may_pull(skb, len) ? 0 : -EINVAL; 1497 } 1498 1499 static int ip_mc_check_igmp_query(struct sk_buff *skb) 1500 { 1501 unsigned int transport_len = ip_transport_len(skb); 1502 unsigned int len; 1503 1504 /* IGMPv{1,2}? */ 1505 if (transport_len != sizeof(struct igmphdr)) { 1506 /* or IGMPv3? */ 1507 if (transport_len < sizeof(struct igmpv3_query)) 1508 return -EINVAL; 1509 1510 len = skb_transport_offset(skb) + sizeof(struct igmpv3_query); 1511 if (!ip_mc_may_pull(skb, len)) 1512 return -EINVAL; 1513 } 1514 1515 /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer 1516 * all-systems destination addresses (224.0.0.1) for general queries 1517 */ 1518 if (!igmp_hdr(skb)->group && 1519 ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP)) 1520 return -EINVAL; 1521 1522 return 0; 1523 } 1524 1525 static int ip_mc_check_igmp_msg(struct sk_buff *skb) 1526 { 1527 switch (igmp_hdr(skb)->type) { 1528 case IGMP_HOST_LEAVE_MESSAGE: 1529 case IGMP_HOST_MEMBERSHIP_REPORT: 1530 case IGMPV2_HOST_MEMBERSHIP_REPORT: 1531 /* fall through */ 1532 return 0; 1533 case IGMPV3_HOST_MEMBERSHIP_REPORT: 1534 return ip_mc_check_igmp_reportv3(skb); 1535 case IGMP_HOST_MEMBERSHIP_QUERY: 1536 return ip_mc_check_igmp_query(skb); 1537 default: 1538 return -ENOMSG; 1539 } 1540 } 1541 1542 static inline __sum16 ip_mc_validate_checksum(struct sk_buff *skb) 1543 { 1544 return skb_checksum_simple_validate(skb); 1545 } 1546 1547 static int ip_mc_check_igmp_csum(struct sk_buff *skb) 1548 { 1549 unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr); 1550 unsigned int transport_len = ip_transport_len(skb); 1551 struct sk_buff *skb_chk; 1552 1553 if (!ip_mc_may_pull(skb, len)) 1554 return -EINVAL; 1555 1556 skb_chk = skb_checksum_trimmed(skb, transport_len, 1557 ip_mc_validate_checksum); 1558 if (!skb_chk) 1559 return -EINVAL; 1560 1561 if (skb_chk != skb) 1562 kfree_skb(skb_chk); 1563 1564 return 0; 1565 } 1566 1567 /** 1568 * ip_mc_check_igmp - checks whether this is a sane IGMP packet 1569 * @skb: the skb to validate 1570 * 1571 * Checks whether an IPv4 packet is a valid IGMP packet. If so sets 1572 * skb transport header accordingly and returns zero. 1573 * 1574 * -EINVAL: A broken packet was detected, i.e. it violates some internet 1575 * standard 1576 * -ENOMSG: IP header validation succeeded but it is not an IGMP packet. 1577 * -ENOMEM: A memory allocation failure happened. 1578 * 1579 * Caller needs to set the skb network header and free any returned skb if it 1580 * differs from the provided skb. 1581 */ 1582 int ip_mc_check_igmp(struct sk_buff *skb) 1583 { 1584 int ret = ip_mc_check_iphdr(skb); 1585 1586 if (ret < 0) 1587 return ret; 1588 1589 if (ip_hdr(skb)->protocol != IPPROTO_IGMP) 1590 return -ENOMSG; 1591 1592 ret = ip_mc_check_igmp_csum(skb); 1593 if (ret < 0) 1594 return ret; 1595 1596 return ip_mc_check_igmp_msg(skb); 1597 } 1598 EXPORT_SYMBOL(ip_mc_check_igmp); 1599 1600 /* 1601 * Resend IGMP JOIN report; used by netdev notifier. 1602 */ 1603 static void ip_mc_rejoin_groups(struct in_device *in_dev) 1604 { 1605 #ifdef CONFIG_IP_MULTICAST 1606 struct ip_mc_list *im; 1607 int type; 1608 struct net *net = dev_net(in_dev->dev); 1609 1610 ASSERT_RTNL(); 1611 1612 for_each_pmc_rtnl(in_dev, im) { 1613 if (im->multiaddr == IGMP_ALL_HOSTS) 1614 continue; 1615 if (ipv4_is_local_multicast(im->multiaddr) && 1616 !net->ipv4.sysctl_igmp_llm_reports) 1617 continue; 1618 1619 /* a failover is happening and switches 1620 * must be notified immediately 1621 */ 1622 if (IGMP_V1_SEEN(in_dev)) 1623 type = IGMP_HOST_MEMBERSHIP_REPORT; 1624 else if (IGMP_V2_SEEN(in_dev)) 1625 type = IGMPV2_HOST_MEMBERSHIP_REPORT; 1626 else 1627 type = IGMPV3_HOST_MEMBERSHIP_REPORT; 1628 igmp_send_report(in_dev, im, type); 1629 } 1630 #endif 1631 } 1632 1633 /* 1634 * A socket has left a multicast group on device dev 1635 */ 1636 1637 void ip_mc_dec_group(struct in_device *in_dev, __be32 addr) 1638 { 1639 struct ip_mc_list *i; 1640 struct ip_mc_list __rcu **ip; 1641 1642 ASSERT_RTNL(); 1643 1644 for (ip = &in_dev->mc_list; 1645 (i = rtnl_dereference(*ip)) != NULL; 1646 ip = &i->next_rcu) { 1647 if (i->multiaddr == addr) { 1648 if (--i->users == 0) { 1649 ip_mc_hash_remove(in_dev, i); 1650 *ip = i->next_rcu; 1651 in_dev->mc_count--; 1652 igmp_group_dropped(i); 1653 ip_mc_clear_src(i); 1654 1655 if (!in_dev->dead) 1656 ip_rt_multicast_event(in_dev); 1657 1658 ip_ma_put(i); 1659 return; 1660 } 1661 break; 1662 } 1663 } 1664 } 1665 EXPORT_SYMBOL(ip_mc_dec_group); 1666 1667 /* Device changing type */ 1668 1669 void ip_mc_unmap(struct in_device *in_dev) 1670 { 1671 struct ip_mc_list *pmc; 1672 1673 ASSERT_RTNL(); 1674 1675 for_each_pmc_rtnl(in_dev, pmc) 1676 igmp_group_dropped(pmc); 1677 } 1678 1679 void ip_mc_remap(struct in_device *in_dev) 1680 { 1681 struct ip_mc_list *pmc; 1682 1683 ASSERT_RTNL(); 1684 1685 for_each_pmc_rtnl(in_dev, pmc) { 1686 #ifdef CONFIG_IP_MULTICAST 1687 igmpv3_del_delrec(in_dev, pmc); 1688 #endif 1689 igmp_group_added(pmc); 1690 } 1691 } 1692 1693 /* Device going down */ 1694 1695 void ip_mc_down(struct in_device *in_dev) 1696 { 1697 struct ip_mc_list *pmc; 1698 1699 ASSERT_RTNL(); 1700 1701 for_each_pmc_rtnl(in_dev, pmc) 1702 igmp_group_dropped(pmc); 1703 1704 #ifdef CONFIG_IP_MULTICAST 1705 in_dev->mr_ifc_count = 0; 1706 if (del_timer(&in_dev->mr_ifc_timer)) 1707 __in_dev_put(in_dev); 1708 in_dev->mr_gq_running = 0; 1709 if (del_timer(&in_dev->mr_gq_timer)) 1710 __in_dev_put(in_dev); 1711 #endif 1712 1713 ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS); 1714 } 1715 1716 #ifdef CONFIG_IP_MULTICAST 1717 static void ip_mc_reset(struct in_device *in_dev) 1718 { 1719 struct net *net = dev_net(in_dev->dev); 1720 1721 in_dev->mr_qi = IGMP_QUERY_INTERVAL; 1722 in_dev->mr_qri = IGMP_QUERY_RESPONSE_INTERVAL; 1723 in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv; 1724 } 1725 #else 1726 static void ip_mc_reset(struct in_device *in_dev) 1727 { 1728 } 1729 #endif 1730 1731 void ip_mc_init_dev(struct in_device *in_dev) 1732 { 1733 ASSERT_RTNL(); 1734 1735 #ifdef CONFIG_IP_MULTICAST 1736 timer_setup(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 0); 1737 timer_setup(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 0); 1738 #endif 1739 ip_mc_reset(in_dev); 1740 1741 spin_lock_init(&in_dev->mc_tomb_lock); 1742 } 1743 1744 /* Device going up */ 1745 1746 void ip_mc_up(struct in_device *in_dev) 1747 { 1748 struct ip_mc_list *pmc; 1749 1750 ASSERT_RTNL(); 1751 1752 ip_mc_reset(in_dev); 1753 ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS); 1754 1755 for_each_pmc_rtnl(in_dev, pmc) { 1756 #ifdef CONFIG_IP_MULTICAST 1757 igmpv3_del_delrec(in_dev, pmc); 1758 #endif 1759 igmp_group_added(pmc); 1760 } 1761 } 1762 1763 /* 1764 * Device is about to be destroyed: clean up. 1765 */ 1766 1767 void ip_mc_destroy_dev(struct in_device *in_dev) 1768 { 1769 struct ip_mc_list *i; 1770 1771 ASSERT_RTNL(); 1772 1773 /* Deactivate timers */ 1774 ip_mc_down(in_dev); 1775 #ifdef CONFIG_IP_MULTICAST 1776 igmpv3_clear_delrec(in_dev); 1777 #endif 1778 1779 while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) { 1780 in_dev->mc_list = i->next_rcu; 1781 in_dev->mc_count--; 1782 ip_ma_put(i); 1783 } 1784 } 1785 1786 /* RTNL is locked */ 1787 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr) 1788 { 1789 struct net_device *dev = NULL; 1790 struct in_device *idev = NULL; 1791 1792 if (imr->imr_ifindex) { 1793 idev = inetdev_by_index(net, imr->imr_ifindex); 1794 return idev; 1795 } 1796 if (imr->imr_address.s_addr) { 1797 dev = __ip_dev_find(net, imr->imr_address.s_addr, false); 1798 if (!dev) 1799 return NULL; 1800 } 1801 1802 if (!dev) { 1803 struct rtable *rt = ip_route_output(net, 1804 imr->imr_multiaddr.s_addr, 1805 0, 0, 0); 1806 if (!IS_ERR(rt)) { 1807 dev = rt->dst.dev; 1808 ip_rt_put(rt); 1809 } 1810 } 1811 if (dev) { 1812 imr->imr_ifindex = dev->ifindex; 1813 idev = __in_dev_get_rtnl(dev); 1814 } 1815 return idev; 1816 } 1817 1818 /* 1819 * Join a socket to a group 1820 */ 1821 1822 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode, 1823 __be32 *psfsrc) 1824 { 1825 struct ip_sf_list *psf, *psf_prev; 1826 int rv = 0; 1827 1828 psf_prev = NULL; 1829 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1830 if (psf->sf_inaddr == *psfsrc) 1831 break; 1832 psf_prev = psf; 1833 } 1834 if (!psf || psf->sf_count[sfmode] == 0) { 1835 /* source filter not found, or count wrong => bug */ 1836 return -ESRCH; 1837 } 1838 psf->sf_count[sfmode]--; 1839 if (psf->sf_count[sfmode] == 0) { 1840 ip_rt_multicast_event(pmc->interface); 1841 } 1842 if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) { 1843 #ifdef CONFIG_IP_MULTICAST 1844 struct in_device *in_dev = pmc->interface; 1845 struct net *net = dev_net(in_dev->dev); 1846 #endif 1847 1848 /* no more filters for this source */ 1849 if (psf_prev) 1850 psf_prev->sf_next = psf->sf_next; 1851 else 1852 pmc->sources = psf->sf_next; 1853 #ifdef CONFIG_IP_MULTICAST 1854 if (psf->sf_oldin && 1855 !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) { 1856 psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1857 psf->sf_next = pmc->tomb; 1858 pmc->tomb = psf; 1859 rv = 1; 1860 } else 1861 #endif 1862 kfree(psf); 1863 } 1864 return rv; 1865 } 1866 1867 #ifndef CONFIG_IP_MULTICAST 1868 #define igmp_ifc_event(x) do { } while (0) 1869 #endif 1870 1871 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 1872 int sfcount, __be32 *psfsrc, int delta) 1873 { 1874 struct ip_mc_list *pmc; 1875 int changerec = 0; 1876 int i, err; 1877 1878 if (!in_dev) 1879 return -ENODEV; 1880 rcu_read_lock(); 1881 for_each_pmc_rcu(in_dev, pmc) { 1882 if (*pmca == pmc->multiaddr) 1883 break; 1884 } 1885 if (!pmc) { 1886 /* MCA not found?? bug */ 1887 rcu_read_unlock(); 1888 return -ESRCH; 1889 } 1890 spin_lock_bh(&pmc->lock); 1891 rcu_read_unlock(); 1892 #ifdef CONFIG_IP_MULTICAST 1893 sf_markstate(pmc); 1894 #endif 1895 if (!delta) { 1896 err = -EINVAL; 1897 if (!pmc->sfcount[sfmode]) 1898 goto out_unlock; 1899 pmc->sfcount[sfmode]--; 1900 } 1901 err = 0; 1902 for (i = 0; i < sfcount; i++) { 1903 int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]); 1904 1905 changerec |= rv > 0; 1906 if (!err && rv < 0) 1907 err = rv; 1908 } 1909 if (pmc->sfmode == MCAST_EXCLUDE && 1910 pmc->sfcount[MCAST_EXCLUDE] == 0 && 1911 pmc->sfcount[MCAST_INCLUDE]) { 1912 #ifdef CONFIG_IP_MULTICAST 1913 struct ip_sf_list *psf; 1914 struct net *net = dev_net(in_dev->dev); 1915 #endif 1916 1917 /* filter mode change */ 1918 pmc->sfmode = MCAST_INCLUDE; 1919 #ifdef CONFIG_IP_MULTICAST 1920 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1921 in_dev->mr_ifc_count = pmc->crcount; 1922 for (psf = pmc->sources; psf; psf = psf->sf_next) 1923 psf->sf_crcount = 0; 1924 igmp_ifc_event(pmc->interface); 1925 } else if (sf_setstate(pmc) || changerec) { 1926 igmp_ifc_event(pmc->interface); 1927 #endif 1928 } 1929 out_unlock: 1930 spin_unlock_bh(&pmc->lock); 1931 return err; 1932 } 1933 1934 /* 1935 * Add multicast single-source filter to the interface list 1936 */ 1937 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode, 1938 __be32 *psfsrc) 1939 { 1940 struct ip_sf_list *psf, *psf_prev; 1941 1942 psf_prev = NULL; 1943 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1944 if (psf->sf_inaddr == *psfsrc) 1945 break; 1946 psf_prev = psf; 1947 } 1948 if (!psf) { 1949 psf = kzalloc(sizeof(*psf), GFP_ATOMIC); 1950 if (!psf) 1951 return -ENOBUFS; 1952 psf->sf_inaddr = *psfsrc; 1953 if (psf_prev) { 1954 psf_prev->sf_next = psf; 1955 } else 1956 pmc->sources = psf; 1957 } 1958 psf->sf_count[sfmode]++; 1959 if (psf->sf_count[sfmode] == 1) { 1960 ip_rt_multicast_event(pmc->interface); 1961 } 1962 return 0; 1963 } 1964 1965 #ifdef CONFIG_IP_MULTICAST 1966 static void sf_markstate(struct ip_mc_list *pmc) 1967 { 1968 struct ip_sf_list *psf; 1969 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; 1970 1971 for (psf = pmc->sources; psf; psf = psf->sf_next) 1972 if (pmc->sfcount[MCAST_EXCLUDE]) { 1973 psf->sf_oldin = mca_xcount == 1974 psf->sf_count[MCAST_EXCLUDE] && 1975 !psf->sf_count[MCAST_INCLUDE]; 1976 } else 1977 psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0; 1978 } 1979 1980 static int sf_setstate(struct ip_mc_list *pmc) 1981 { 1982 struct ip_sf_list *psf, *dpsf; 1983 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; 1984 int qrv = pmc->interface->mr_qrv; 1985 int new_in, rv; 1986 1987 rv = 0; 1988 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1989 if (pmc->sfcount[MCAST_EXCLUDE]) { 1990 new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] && 1991 !psf->sf_count[MCAST_INCLUDE]; 1992 } else 1993 new_in = psf->sf_count[MCAST_INCLUDE] != 0; 1994 if (new_in) { 1995 if (!psf->sf_oldin) { 1996 struct ip_sf_list *prev = NULL; 1997 1998 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) { 1999 if (dpsf->sf_inaddr == psf->sf_inaddr) 2000 break; 2001 prev = dpsf; 2002 } 2003 if (dpsf) { 2004 if (prev) 2005 prev->sf_next = dpsf->sf_next; 2006 else 2007 pmc->tomb = dpsf->sf_next; 2008 kfree(dpsf); 2009 } 2010 psf->sf_crcount = qrv; 2011 rv++; 2012 } 2013 } else if (psf->sf_oldin) { 2014 2015 psf->sf_crcount = 0; 2016 /* 2017 * add or update "delete" records if an active filter 2018 * is now inactive 2019 */ 2020 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) 2021 if (dpsf->sf_inaddr == psf->sf_inaddr) 2022 break; 2023 if (!dpsf) { 2024 dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC); 2025 if (!dpsf) 2026 continue; 2027 *dpsf = *psf; 2028 /* pmc->lock held by callers */ 2029 dpsf->sf_next = pmc->tomb; 2030 pmc->tomb = dpsf; 2031 } 2032 dpsf->sf_crcount = qrv; 2033 rv++; 2034 } 2035 } 2036 return rv; 2037 } 2038 #endif 2039 2040 /* 2041 * Add multicast source filter list to the interface list 2042 */ 2043 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 2044 int sfcount, __be32 *psfsrc, int delta) 2045 { 2046 struct ip_mc_list *pmc; 2047 int isexclude; 2048 int i, err; 2049 2050 if (!in_dev) 2051 return -ENODEV; 2052 rcu_read_lock(); 2053 for_each_pmc_rcu(in_dev, pmc) { 2054 if (*pmca == pmc->multiaddr) 2055 break; 2056 } 2057 if (!pmc) { 2058 /* MCA not found?? bug */ 2059 rcu_read_unlock(); 2060 return -ESRCH; 2061 } 2062 spin_lock_bh(&pmc->lock); 2063 rcu_read_unlock(); 2064 2065 #ifdef CONFIG_IP_MULTICAST 2066 sf_markstate(pmc); 2067 #endif 2068 isexclude = pmc->sfmode == MCAST_EXCLUDE; 2069 if (!delta) 2070 pmc->sfcount[sfmode]++; 2071 err = 0; 2072 for (i = 0; i < sfcount; i++) { 2073 err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]); 2074 if (err) 2075 break; 2076 } 2077 if (err) { 2078 int j; 2079 2080 if (!delta) 2081 pmc->sfcount[sfmode]--; 2082 for (j = 0; j < i; j++) 2083 (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]); 2084 } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) { 2085 #ifdef CONFIG_IP_MULTICAST 2086 struct ip_sf_list *psf; 2087 struct net *net = dev_net(pmc->interface->dev); 2088 in_dev = pmc->interface; 2089 #endif 2090 2091 /* filter mode change */ 2092 if (pmc->sfcount[MCAST_EXCLUDE]) 2093 pmc->sfmode = MCAST_EXCLUDE; 2094 else if (pmc->sfcount[MCAST_INCLUDE]) 2095 pmc->sfmode = MCAST_INCLUDE; 2096 #ifdef CONFIG_IP_MULTICAST 2097 /* else no filters; keep old mode for reports */ 2098 2099 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 2100 in_dev->mr_ifc_count = pmc->crcount; 2101 for (psf = pmc->sources; psf; psf = psf->sf_next) 2102 psf->sf_crcount = 0; 2103 igmp_ifc_event(in_dev); 2104 } else if (sf_setstate(pmc)) { 2105 igmp_ifc_event(in_dev); 2106 #endif 2107 } 2108 spin_unlock_bh(&pmc->lock); 2109 return err; 2110 } 2111 2112 static void ip_mc_clear_src(struct ip_mc_list *pmc) 2113 { 2114 struct ip_sf_list *psf, *nextpsf, *tomb, *sources; 2115 2116 spin_lock_bh(&pmc->lock); 2117 tomb = pmc->tomb; 2118 pmc->tomb = NULL; 2119 sources = pmc->sources; 2120 pmc->sources = NULL; 2121 pmc->sfmode = MCAST_EXCLUDE; 2122 pmc->sfcount[MCAST_INCLUDE] = 0; 2123 pmc->sfcount[MCAST_EXCLUDE] = 1; 2124 spin_unlock_bh(&pmc->lock); 2125 2126 for (psf = tomb; psf; psf = nextpsf) { 2127 nextpsf = psf->sf_next; 2128 kfree(psf); 2129 } 2130 for (psf = sources; psf; psf = nextpsf) { 2131 nextpsf = psf->sf_next; 2132 kfree(psf); 2133 } 2134 } 2135 2136 /* Join a multicast group 2137 */ 2138 static int __ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr, 2139 unsigned int mode) 2140 { 2141 __be32 addr = imr->imr_multiaddr.s_addr; 2142 struct ip_mc_socklist *iml, *i; 2143 struct in_device *in_dev; 2144 struct inet_sock *inet = inet_sk(sk); 2145 struct net *net = sock_net(sk); 2146 int ifindex; 2147 int count = 0; 2148 int err; 2149 2150 ASSERT_RTNL(); 2151 2152 if (!ipv4_is_multicast(addr)) 2153 return -EINVAL; 2154 2155 in_dev = ip_mc_find_dev(net, imr); 2156 2157 if (!in_dev) { 2158 err = -ENODEV; 2159 goto done; 2160 } 2161 2162 err = -EADDRINUSE; 2163 ifindex = imr->imr_ifindex; 2164 for_each_pmc_rtnl(inet, i) { 2165 if (i->multi.imr_multiaddr.s_addr == addr && 2166 i->multi.imr_ifindex == ifindex) 2167 goto done; 2168 count++; 2169 } 2170 err = -ENOBUFS; 2171 if (count >= net->ipv4.sysctl_igmp_max_memberships) 2172 goto done; 2173 iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL); 2174 if (!iml) 2175 goto done; 2176 2177 memcpy(&iml->multi, imr, sizeof(*imr)); 2178 iml->next_rcu = inet->mc_list; 2179 iml->sflist = NULL; 2180 iml->sfmode = mode; 2181 rcu_assign_pointer(inet->mc_list, iml); 2182 __ip_mc_inc_group(in_dev, addr, mode); 2183 err = 0; 2184 done: 2185 return err; 2186 } 2187 2188 /* Join ASM (Any-Source Multicast) group 2189 */ 2190 int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr) 2191 { 2192 return __ip_mc_join_group(sk, imr, MCAST_EXCLUDE); 2193 } 2194 EXPORT_SYMBOL(ip_mc_join_group); 2195 2196 /* Join SSM (Source-Specific Multicast) group 2197 */ 2198 int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr, 2199 unsigned int mode) 2200 { 2201 return __ip_mc_join_group(sk, imr, mode); 2202 } 2203 2204 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml, 2205 struct in_device *in_dev) 2206 { 2207 struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist); 2208 int err; 2209 2210 if (!psf) { 2211 /* any-source empty exclude case */ 2212 return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, 2213 iml->sfmode, 0, NULL, 0); 2214 } 2215 err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, 2216 iml->sfmode, psf->sl_count, psf->sl_addr, 0); 2217 RCU_INIT_POINTER(iml->sflist, NULL); 2218 /* decrease mem now to avoid the memleak warning */ 2219 atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc); 2220 kfree_rcu(psf, rcu); 2221 return err; 2222 } 2223 2224 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr) 2225 { 2226 struct inet_sock *inet = inet_sk(sk); 2227 struct ip_mc_socklist *iml; 2228 struct ip_mc_socklist __rcu **imlp; 2229 struct in_device *in_dev; 2230 struct net *net = sock_net(sk); 2231 __be32 group = imr->imr_multiaddr.s_addr; 2232 u32 ifindex; 2233 int ret = -EADDRNOTAVAIL; 2234 2235 ASSERT_RTNL(); 2236 2237 in_dev = ip_mc_find_dev(net, imr); 2238 if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) { 2239 ret = -ENODEV; 2240 goto out; 2241 } 2242 ifindex = imr->imr_ifindex; 2243 for (imlp = &inet->mc_list; 2244 (iml = rtnl_dereference(*imlp)) != NULL; 2245 imlp = &iml->next_rcu) { 2246 if (iml->multi.imr_multiaddr.s_addr != group) 2247 continue; 2248 if (ifindex) { 2249 if (iml->multi.imr_ifindex != ifindex) 2250 continue; 2251 } else if (imr->imr_address.s_addr && imr->imr_address.s_addr != 2252 iml->multi.imr_address.s_addr) 2253 continue; 2254 2255 (void) ip_mc_leave_src(sk, iml, in_dev); 2256 2257 *imlp = iml->next_rcu; 2258 2259 if (in_dev) 2260 ip_mc_dec_group(in_dev, group); 2261 2262 /* decrease mem now to avoid the memleak warning */ 2263 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); 2264 kfree_rcu(iml, rcu); 2265 return 0; 2266 } 2267 out: 2268 return ret; 2269 } 2270 EXPORT_SYMBOL(ip_mc_leave_group); 2271 2272 int ip_mc_source(int add, int omode, struct sock *sk, struct 2273 ip_mreq_source *mreqs, int ifindex) 2274 { 2275 int err; 2276 struct ip_mreqn imr; 2277 __be32 addr = mreqs->imr_multiaddr; 2278 struct ip_mc_socklist *pmc; 2279 struct in_device *in_dev = NULL; 2280 struct inet_sock *inet = inet_sk(sk); 2281 struct ip_sf_socklist *psl; 2282 struct net *net = sock_net(sk); 2283 int leavegroup = 0; 2284 int i, j, rv; 2285 2286 if (!ipv4_is_multicast(addr)) 2287 return -EINVAL; 2288 2289 ASSERT_RTNL(); 2290 2291 imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr; 2292 imr.imr_address.s_addr = mreqs->imr_interface; 2293 imr.imr_ifindex = ifindex; 2294 in_dev = ip_mc_find_dev(net, &imr); 2295 2296 if (!in_dev) { 2297 err = -ENODEV; 2298 goto done; 2299 } 2300 err = -EADDRNOTAVAIL; 2301 2302 for_each_pmc_rtnl(inet, pmc) { 2303 if ((pmc->multi.imr_multiaddr.s_addr == 2304 imr.imr_multiaddr.s_addr) && 2305 (pmc->multi.imr_ifindex == imr.imr_ifindex)) 2306 break; 2307 } 2308 if (!pmc) { /* must have a prior join */ 2309 err = -EINVAL; 2310 goto done; 2311 } 2312 /* if a source filter was set, must be the same mode as before */ 2313 if (pmc->sflist) { 2314 if (pmc->sfmode != omode) { 2315 err = -EINVAL; 2316 goto done; 2317 } 2318 } else if (pmc->sfmode != omode) { 2319 /* allow mode switches for empty-set filters */ 2320 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0); 2321 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0, 2322 NULL, 0); 2323 pmc->sfmode = omode; 2324 } 2325 2326 psl = rtnl_dereference(pmc->sflist); 2327 if (!add) { 2328 if (!psl) 2329 goto done; /* err = -EADDRNOTAVAIL */ 2330 rv = !0; 2331 for (i = 0; i < psl->sl_count; i++) { 2332 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr, 2333 sizeof(__be32)); 2334 if (rv == 0) 2335 break; 2336 } 2337 if (rv) /* source not found */ 2338 goto done; /* err = -EADDRNOTAVAIL */ 2339 2340 /* special case - (INCLUDE, empty) == LEAVE_GROUP */ 2341 if (psl->sl_count == 1 && omode == MCAST_INCLUDE) { 2342 leavegroup = 1; 2343 goto done; 2344 } 2345 2346 /* update the interface filter */ 2347 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1, 2348 &mreqs->imr_sourceaddr, 1); 2349 2350 for (j = i+1; j < psl->sl_count; j++) 2351 psl->sl_addr[j-1] = psl->sl_addr[j]; 2352 psl->sl_count--; 2353 err = 0; 2354 goto done; 2355 } 2356 /* else, add a new source to the filter */ 2357 2358 if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) { 2359 err = -ENOBUFS; 2360 goto done; 2361 } 2362 if (!psl || psl->sl_count == psl->sl_max) { 2363 struct ip_sf_socklist *newpsl; 2364 int count = IP_SFBLOCK; 2365 2366 if (psl) 2367 count += psl->sl_max; 2368 newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL); 2369 if (!newpsl) { 2370 err = -ENOBUFS; 2371 goto done; 2372 } 2373 newpsl->sl_max = count; 2374 newpsl->sl_count = count - IP_SFBLOCK; 2375 if (psl) { 2376 for (i = 0; i < psl->sl_count; i++) 2377 newpsl->sl_addr[i] = psl->sl_addr[i]; 2378 /* decrease mem now to avoid the memleak warning */ 2379 atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc); 2380 kfree_rcu(psl, rcu); 2381 } 2382 rcu_assign_pointer(pmc->sflist, newpsl); 2383 psl = newpsl; 2384 } 2385 rv = 1; /* > 0 for insert logic below if sl_count is 0 */ 2386 for (i = 0; i < psl->sl_count; i++) { 2387 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr, 2388 sizeof(__be32)); 2389 if (rv == 0) 2390 break; 2391 } 2392 if (rv == 0) /* address already there is an error */ 2393 goto done; 2394 for (j = psl->sl_count-1; j >= i; j--) 2395 psl->sl_addr[j+1] = psl->sl_addr[j]; 2396 psl->sl_addr[i] = mreqs->imr_sourceaddr; 2397 psl->sl_count++; 2398 err = 0; 2399 /* update the interface list */ 2400 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1, 2401 &mreqs->imr_sourceaddr, 1); 2402 done: 2403 if (leavegroup) 2404 err = ip_mc_leave_group(sk, &imr); 2405 return err; 2406 } 2407 2408 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex) 2409 { 2410 int err = 0; 2411 struct ip_mreqn imr; 2412 __be32 addr = msf->imsf_multiaddr; 2413 struct ip_mc_socklist *pmc; 2414 struct in_device *in_dev; 2415 struct inet_sock *inet = inet_sk(sk); 2416 struct ip_sf_socklist *newpsl, *psl; 2417 struct net *net = sock_net(sk); 2418 int leavegroup = 0; 2419 2420 if (!ipv4_is_multicast(addr)) 2421 return -EINVAL; 2422 if (msf->imsf_fmode != MCAST_INCLUDE && 2423 msf->imsf_fmode != MCAST_EXCLUDE) 2424 return -EINVAL; 2425 2426 ASSERT_RTNL(); 2427 2428 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; 2429 imr.imr_address.s_addr = msf->imsf_interface; 2430 imr.imr_ifindex = ifindex; 2431 in_dev = ip_mc_find_dev(net, &imr); 2432 2433 if (!in_dev) { 2434 err = -ENODEV; 2435 goto done; 2436 } 2437 2438 /* special case - (INCLUDE, empty) == LEAVE_GROUP */ 2439 if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) { 2440 leavegroup = 1; 2441 goto done; 2442 } 2443 2444 for_each_pmc_rtnl(inet, pmc) { 2445 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && 2446 pmc->multi.imr_ifindex == imr.imr_ifindex) 2447 break; 2448 } 2449 if (!pmc) { /* must have a prior join */ 2450 err = -EINVAL; 2451 goto done; 2452 } 2453 if (msf->imsf_numsrc) { 2454 newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc), 2455 GFP_KERNEL); 2456 if (!newpsl) { 2457 err = -ENOBUFS; 2458 goto done; 2459 } 2460 newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc; 2461 memcpy(newpsl->sl_addr, msf->imsf_slist, 2462 msf->imsf_numsrc * sizeof(msf->imsf_slist[0])); 2463 err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr, 2464 msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0); 2465 if (err) { 2466 sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max)); 2467 goto done; 2468 } 2469 } else { 2470 newpsl = NULL; 2471 (void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr, 2472 msf->imsf_fmode, 0, NULL, 0); 2473 } 2474 psl = rtnl_dereference(pmc->sflist); 2475 if (psl) { 2476 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, 2477 psl->sl_count, psl->sl_addr, 0); 2478 /* decrease mem now to avoid the memleak warning */ 2479 atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc); 2480 kfree_rcu(psl, rcu); 2481 } else 2482 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, 2483 0, NULL, 0); 2484 rcu_assign_pointer(pmc->sflist, newpsl); 2485 pmc->sfmode = msf->imsf_fmode; 2486 err = 0; 2487 done: 2488 if (leavegroup) 2489 err = ip_mc_leave_group(sk, &imr); 2490 return err; 2491 } 2492 2493 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf, 2494 struct ip_msfilter __user *optval, int __user *optlen) 2495 { 2496 int err, len, count, copycount; 2497 struct ip_mreqn imr; 2498 __be32 addr = msf->imsf_multiaddr; 2499 struct ip_mc_socklist *pmc; 2500 struct in_device *in_dev; 2501 struct inet_sock *inet = inet_sk(sk); 2502 struct ip_sf_socklist *psl; 2503 struct net *net = sock_net(sk); 2504 2505 ASSERT_RTNL(); 2506 2507 if (!ipv4_is_multicast(addr)) 2508 return -EINVAL; 2509 2510 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; 2511 imr.imr_address.s_addr = msf->imsf_interface; 2512 imr.imr_ifindex = 0; 2513 in_dev = ip_mc_find_dev(net, &imr); 2514 2515 if (!in_dev) { 2516 err = -ENODEV; 2517 goto done; 2518 } 2519 err = -EADDRNOTAVAIL; 2520 2521 for_each_pmc_rtnl(inet, pmc) { 2522 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && 2523 pmc->multi.imr_ifindex == imr.imr_ifindex) 2524 break; 2525 } 2526 if (!pmc) /* must have a prior join */ 2527 goto done; 2528 msf->imsf_fmode = pmc->sfmode; 2529 psl = rtnl_dereference(pmc->sflist); 2530 if (!psl) { 2531 len = 0; 2532 count = 0; 2533 } else { 2534 count = psl->sl_count; 2535 } 2536 copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc; 2537 len = copycount * sizeof(psl->sl_addr[0]); 2538 msf->imsf_numsrc = count; 2539 if (put_user(IP_MSFILTER_SIZE(copycount), optlen) || 2540 copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) { 2541 return -EFAULT; 2542 } 2543 if (len && 2544 copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len)) 2545 return -EFAULT; 2546 return 0; 2547 done: 2548 return err; 2549 } 2550 2551 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf, 2552 struct group_filter __user *optval, int __user *optlen) 2553 { 2554 int err, i, count, copycount; 2555 struct sockaddr_in *psin; 2556 __be32 addr; 2557 struct ip_mc_socklist *pmc; 2558 struct inet_sock *inet = inet_sk(sk); 2559 struct ip_sf_socklist *psl; 2560 2561 ASSERT_RTNL(); 2562 2563 psin = (struct sockaddr_in *)&gsf->gf_group; 2564 if (psin->sin_family != AF_INET) 2565 return -EINVAL; 2566 addr = psin->sin_addr.s_addr; 2567 if (!ipv4_is_multicast(addr)) 2568 return -EINVAL; 2569 2570 err = -EADDRNOTAVAIL; 2571 2572 for_each_pmc_rtnl(inet, pmc) { 2573 if (pmc->multi.imr_multiaddr.s_addr == addr && 2574 pmc->multi.imr_ifindex == gsf->gf_interface) 2575 break; 2576 } 2577 if (!pmc) /* must have a prior join */ 2578 goto done; 2579 gsf->gf_fmode = pmc->sfmode; 2580 psl = rtnl_dereference(pmc->sflist); 2581 count = psl ? psl->sl_count : 0; 2582 copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc; 2583 gsf->gf_numsrc = count; 2584 if (put_user(GROUP_FILTER_SIZE(copycount), optlen) || 2585 copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) { 2586 return -EFAULT; 2587 } 2588 for (i = 0; i < copycount; i++) { 2589 struct sockaddr_storage ss; 2590 2591 psin = (struct sockaddr_in *)&ss; 2592 memset(&ss, 0, sizeof(ss)); 2593 psin->sin_family = AF_INET; 2594 psin->sin_addr.s_addr = psl->sl_addr[i]; 2595 if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss))) 2596 return -EFAULT; 2597 } 2598 return 0; 2599 done: 2600 return err; 2601 } 2602 2603 /* 2604 * check if a multicast source filter allows delivery for a given <src,dst,intf> 2605 */ 2606 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, 2607 int dif, int sdif) 2608 { 2609 struct inet_sock *inet = inet_sk(sk); 2610 struct ip_mc_socklist *pmc; 2611 struct ip_sf_socklist *psl; 2612 int i; 2613 int ret; 2614 2615 ret = 1; 2616 if (!ipv4_is_multicast(loc_addr)) 2617 goto out; 2618 2619 rcu_read_lock(); 2620 for_each_pmc_rcu(inet, pmc) { 2621 if (pmc->multi.imr_multiaddr.s_addr == loc_addr && 2622 (pmc->multi.imr_ifindex == dif || 2623 (sdif && pmc->multi.imr_ifindex == sdif))) 2624 break; 2625 } 2626 ret = inet->mc_all; 2627 if (!pmc) 2628 goto unlock; 2629 psl = rcu_dereference(pmc->sflist); 2630 ret = (pmc->sfmode == MCAST_EXCLUDE); 2631 if (!psl) 2632 goto unlock; 2633 2634 for (i = 0; i < psl->sl_count; i++) { 2635 if (psl->sl_addr[i] == rmt_addr) 2636 break; 2637 } 2638 ret = 0; 2639 if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count) 2640 goto unlock; 2641 if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count) 2642 goto unlock; 2643 ret = 1; 2644 unlock: 2645 rcu_read_unlock(); 2646 out: 2647 return ret; 2648 } 2649 2650 /* 2651 * A socket is closing. 2652 */ 2653 2654 void ip_mc_drop_socket(struct sock *sk) 2655 { 2656 struct inet_sock *inet = inet_sk(sk); 2657 struct ip_mc_socklist *iml; 2658 struct net *net = sock_net(sk); 2659 2660 if (!inet->mc_list) 2661 return; 2662 2663 rtnl_lock(); 2664 while ((iml = rtnl_dereference(inet->mc_list)) != NULL) { 2665 struct in_device *in_dev; 2666 2667 inet->mc_list = iml->next_rcu; 2668 in_dev = inetdev_by_index(net, iml->multi.imr_ifindex); 2669 (void) ip_mc_leave_src(sk, iml, in_dev); 2670 if (in_dev) 2671 ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr); 2672 /* decrease mem now to avoid the memleak warning */ 2673 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); 2674 kfree_rcu(iml, rcu); 2675 } 2676 rtnl_unlock(); 2677 } 2678 2679 /* called with rcu_read_lock() */ 2680 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto) 2681 { 2682 struct ip_mc_list *im; 2683 struct ip_mc_list __rcu **mc_hash; 2684 struct ip_sf_list *psf; 2685 int rv = 0; 2686 2687 mc_hash = rcu_dereference(in_dev->mc_hash); 2688 if (mc_hash) { 2689 u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG); 2690 2691 for (im = rcu_dereference(mc_hash[hash]); 2692 im != NULL; 2693 im = rcu_dereference(im->next_hash)) { 2694 if (im->multiaddr == mc_addr) 2695 break; 2696 } 2697 } else { 2698 for_each_pmc_rcu(in_dev, im) { 2699 if (im->multiaddr == mc_addr) 2700 break; 2701 } 2702 } 2703 if (im && proto == IPPROTO_IGMP) { 2704 rv = 1; 2705 } else if (im) { 2706 if (src_addr) { 2707 for (psf = im->sources; psf; psf = psf->sf_next) { 2708 if (psf->sf_inaddr == src_addr) 2709 break; 2710 } 2711 if (psf) 2712 rv = psf->sf_count[MCAST_INCLUDE] || 2713 psf->sf_count[MCAST_EXCLUDE] != 2714 im->sfcount[MCAST_EXCLUDE]; 2715 else 2716 rv = im->sfcount[MCAST_EXCLUDE] != 0; 2717 } else 2718 rv = 1; /* unspecified source; tentatively allow */ 2719 } 2720 return rv; 2721 } 2722 2723 #if defined(CONFIG_PROC_FS) 2724 struct igmp_mc_iter_state { 2725 struct seq_net_private p; 2726 struct net_device *dev; 2727 struct in_device *in_dev; 2728 }; 2729 2730 #define igmp_mc_seq_private(seq) ((struct igmp_mc_iter_state *)(seq)->private) 2731 2732 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq) 2733 { 2734 struct net *net = seq_file_net(seq); 2735 struct ip_mc_list *im = NULL; 2736 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2737 2738 state->in_dev = NULL; 2739 for_each_netdev_rcu(net, state->dev) { 2740 struct in_device *in_dev; 2741 2742 in_dev = __in_dev_get_rcu(state->dev); 2743 if (!in_dev) 2744 continue; 2745 im = rcu_dereference(in_dev->mc_list); 2746 if (im) { 2747 state->in_dev = in_dev; 2748 break; 2749 } 2750 } 2751 return im; 2752 } 2753 2754 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im) 2755 { 2756 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2757 2758 im = rcu_dereference(im->next_rcu); 2759 while (!im) { 2760 state->dev = next_net_device_rcu(state->dev); 2761 if (!state->dev) { 2762 state->in_dev = NULL; 2763 break; 2764 } 2765 state->in_dev = __in_dev_get_rcu(state->dev); 2766 if (!state->in_dev) 2767 continue; 2768 im = rcu_dereference(state->in_dev->mc_list); 2769 } 2770 return im; 2771 } 2772 2773 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos) 2774 { 2775 struct ip_mc_list *im = igmp_mc_get_first(seq); 2776 if (im) 2777 while (pos && (im = igmp_mc_get_next(seq, im)) != NULL) 2778 --pos; 2779 return pos ? NULL : im; 2780 } 2781 2782 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos) 2783 __acquires(rcu) 2784 { 2785 rcu_read_lock(); 2786 return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 2787 } 2788 2789 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2790 { 2791 struct ip_mc_list *im; 2792 if (v == SEQ_START_TOKEN) 2793 im = igmp_mc_get_first(seq); 2794 else 2795 im = igmp_mc_get_next(seq, v); 2796 ++*pos; 2797 return im; 2798 } 2799 2800 static void igmp_mc_seq_stop(struct seq_file *seq, void *v) 2801 __releases(rcu) 2802 { 2803 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2804 2805 state->in_dev = NULL; 2806 state->dev = NULL; 2807 rcu_read_unlock(); 2808 } 2809 2810 static int igmp_mc_seq_show(struct seq_file *seq, void *v) 2811 { 2812 if (v == SEQ_START_TOKEN) 2813 seq_puts(seq, 2814 "Idx\tDevice : Count Querier\tGroup Users Timer\tReporter\n"); 2815 else { 2816 struct ip_mc_list *im = (struct ip_mc_list *)v; 2817 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2818 char *querier; 2819 long delta; 2820 2821 #ifdef CONFIG_IP_MULTICAST 2822 querier = IGMP_V1_SEEN(state->in_dev) ? "V1" : 2823 IGMP_V2_SEEN(state->in_dev) ? "V2" : 2824 "V3"; 2825 #else 2826 querier = "NONE"; 2827 #endif 2828 2829 if (rcu_access_pointer(state->in_dev->mc_list) == im) { 2830 seq_printf(seq, "%d\t%-10s: %5d %7s\n", 2831 state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier); 2832 } 2833 2834 delta = im->timer.expires - jiffies; 2835 seq_printf(seq, 2836 "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n", 2837 im->multiaddr, im->users, 2838 im->tm_running, 2839 im->tm_running ? jiffies_delta_to_clock_t(delta) : 0, 2840 im->reporter); 2841 } 2842 return 0; 2843 } 2844 2845 static const struct seq_operations igmp_mc_seq_ops = { 2846 .start = igmp_mc_seq_start, 2847 .next = igmp_mc_seq_next, 2848 .stop = igmp_mc_seq_stop, 2849 .show = igmp_mc_seq_show, 2850 }; 2851 2852 struct igmp_mcf_iter_state { 2853 struct seq_net_private p; 2854 struct net_device *dev; 2855 struct in_device *idev; 2856 struct ip_mc_list *im; 2857 }; 2858 2859 #define igmp_mcf_seq_private(seq) ((struct igmp_mcf_iter_state *)(seq)->private) 2860 2861 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq) 2862 { 2863 struct net *net = seq_file_net(seq); 2864 struct ip_sf_list *psf = NULL; 2865 struct ip_mc_list *im = NULL; 2866 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2867 2868 state->idev = NULL; 2869 state->im = NULL; 2870 for_each_netdev_rcu(net, state->dev) { 2871 struct in_device *idev; 2872 idev = __in_dev_get_rcu(state->dev); 2873 if (unlikely(!idev)) 2874 continue; 2875 im = rcu_dereference(idev->mc_list); 2876 if (likely(im)) { 2877 spin_lock_bh(&im->lock); 2878 psf = im->sources; 2879 if (likely(psf)) { 2880 state->im = im; 2881 state->idev = idev; 2882 break; 2883 } 2884 spin_unlock_bh(&im->lock); 2885 } 2886 } 2887 return psf; 2888 } 2889 2890 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf) 2891 { 2892 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2893 2894 psf = psf->sf_next; 2895 while (!psf) { 2896 spin_unlock_bh(&state->im->lock); 2897 state->im = state->im->next; 2898 while (!state->im) { 2899 state->dev = next_net_device_rcu(state->dev); 2900 if (!state->dev) { 2901 state->idev = NULL; 2902 goto out; 2903 } 2904 state->idev = __in_dev_get_rcu(state->dev); 2905 if (!state->idev) 2906 continue; 2907 state->im = rcu_dereference(state->idev->mc_list); 2908 } 2909 if (!state->im) 2910 break; 2911 spin_lock_bh(&state->im->lock); 2912 psf = state->im->sources; 2913 } 2914 out: 2915 return psf; 2916 } 2917 2918 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos) 2919 { 2920 struct ip_sf_list *psf = igmp_mcf_get_first(seq); 2921 if (psf) 2922 while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL) 2923 --pos; 2924 return pos ? NULL : psf; 2925 } 2926 2927 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos) 2928 __acquires(rcu) 2929 { 2930 rcu_read_lock(); 2931 return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 2932 } 2933 2934 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2935 { 2936 struct ip_sf_list *psf; 2937 if (v == SEQ_START_TOKEN) 2938 psf = igmp_mcf_get_first(seq); 2939 else 2940 psf = igmp_mcf_get_next(seq, v); 2941 ++*pos; 2942 return psf; 2943 } 2944 2945 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v) 2946 __releases(rcu) 2947 { 2948 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2949 if (likely(state->im)) { 2950 spin_unlock_bh(&state->im->lock); 2951 state->im = NULL; 2952 } 2953 state->idev = NULL; 2954 state->dev = NULL; 2955 rcu_read_unlock(); 2956 } 2957 2958 static int igmp_mcf_seq_show(struct seq_file *seq, void *v) 2959 { 2960 struct ip_sf_list *psf = (struct ip_sf_list *)v; 2961 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2962 2963 if (v == SEQ_START_TOKEN) { 2964 seq_puts(seq, "Idx Device MCA SRC INC EXC\n"); 2965 } else { 2966 seq_printf(seq, 2967 "%3d %6.6s 0x%08x " 2968 "0x%08x %6lu %6lu\n", 2969 state->dev->ifindex, state->dev->name, 2970 ntohl(state->im->multiaddr), 2971 ntohl(psf->sf_inaddr), 2972 psf->sf_count[MCAST_INCLUDE], 2973 psf->sf_count[MCAST_EXCLUDE]); 2974 } 2975 return 0; 2976 } 2977 2978 static const struct seq_operations igmp_mcf_seq_ops = { 2979 .start = igmp_mcf_seq_start, 2980 .next = igmp_mcf_seq_next, 2981 .stop = igmp_mcf_seq_stop, 2982 .show = igmp_mcf_seq_show, 2983 }; 2984 2985 static int __net_init igmp_net_init(struct net *net) 2986 { 2987 struct proc_dir_entry *pde; 2988 int err; 2989 2990 pde = proc_create_net("igmp", 0444, net->proc_net, &igmp_mc_seq_ops, 2991 sizeof(struct igmp_mc_iter_state)); 2992 if (!pde) 2993 goto out_igmp; 2994 pde = proc_create_net("mcfilter", 0444, net->proc_net, 2995 &igmp_mcf_seq_ops, sizeof(struct igmp_mcf_iter_state)); 2996 if (!pde) 2997 goto out_mcfilter; 2998 err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET, 2999 SOCK_DGRAM, 0, net); 3000 if (err < 0) { 3001 pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n", 3002 err); 3003 goto out_sock; 3004 } 3005 3006 return 0; 3007 3008 out_sock: 3009 remove_proc_entry("mcfilter", net->proc_net); 3010 out_mcfilter: 3011 remove_proc_entry("igmp", net->proc_net); 3012 out_igmp: 3013 return -ENOMEM; 3014 } 3015 3016 static void __net_exit igmp_net_exit(struct net *net) 3017 { 3018 remove_proc_entry("mcfilter", net->proc_net); 3019 remove_proc_entry("igmp", net->proc_net); 3020 inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk); 3021 } 3022 3023 static struct pernet_operations igmp_net_ops = { 3024 .init = igmp_net_init, 3025 .exit = igmp_net_exit, 3026 }; 3027 #endif 3028 3029 static int igmp_netdev_event(struct notifier_block *this, 3030 unsigned long event, void *ptr) 3031 { 3032 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 3033 struct in_device *in_dev; 3034 3035 switch (event) { 3036 case NETDEV_RESEND_IGMP: 3037 in_dev = __in_dev_get_rtnl(dev); 3038 if (in_dev) 3039 ip_mc_rejoin_groups(in_dev); 3040 break; 3041 default: 3042 break; 3043 } 3044 return NOTIFY_DONE; 3045 } 3046 3047 static struct notifier_block igmp_notifier = { 3048 .notifier_call = igmp_netdev_event, 3049 }; 3050 3051 int __init igmp_mc_init(void) 3052 { 3053 #if defined(CONFIG_PROC_FS) 3054 int err; 3055 3056 err = register_pernet_subsys(&igmp_net_ops); 3057 if (err) 3058 return err; 3059 err = register_netdevice_notifier(&igmp_notifier); 3060 if (err) 3061 goto reg_notif_fail; 3062 return 0; 3063 3064 reg_notif_fail: 3065 unregister_pernet_subsys(&igmp_net_ops); 3066 return err; 3067 #else 3068 return register_netdevice_notifier(&igmp_notifier); 3069 #endif 3070 } 3071