1 /* 2 * Linux NET3: Internet Group Management Protocol [IGMP] 3 * 4 * This code implements the IGMP protocol as defined in RFC1112. There has 5 * been a further revision of this protocol since which is now supported. 6 * 7 * If you have trouble with this module be careful what gcc you have used, 8 * the older version didn't come out right using gcc 2.5.8, the newer one 9 * seems to fall out with gcc 2.6.2. 10 * 11 * Authors: 12 * Alan Cox <alan@lxorguk.ukuu.org.uk> 13 * 14 * This program is free software; you can redistribute it and/or 15 * modify it under the terms of the GNU General Public License 16 * as published by the Free Software Foundation; either version 17 * 2 of the License, or (at your option) any later version. 18 * 19 * Fixes: 20 * 21 * Alan Cox : Added lots of __inline__ to optimise 22 * the memory usage of all the tiny little 23 * functions. 24 * Alan Cox : Dumped the header building experiment. 25 * Alan Cox : Minor tweaks ready for multicast routing 26 * and extended IGMP protocol. 27 * Alan Cox : Removed a load of inline directives. Gcc 2.5.8 28 * writes utterly bogus code otherwise (sigh) 29 * fixed IGMP loopback to behave in the manner 30 * desired by mrouted, fixed the fact it has been 31 * broken since 1.3.6 and cleaned up a few minor 32 * points. 33 * 34 * Chih-Jen Chang : Tried to revise IGMP to Version 2 35 * Tsu-Sheng Tsao E-mail: chihjenc@scf.usc.edu and tsusheng@scf.usc.edu 36 * The enhancements are mainly based on Steve Deering's 37 * ipmulti-3.5 source code. 38 * Chih-Jen Chang : Added the igmp_get_mrouter_info and 39 * Tsu-Sheng Tsao igmp_set_mrouter_info to keep track of 40 * the mrouted version on that device. 41 * Chih-Jen Chang : Added the max_resp_time parameter to 42 * Tsu-Sheng Tsao igmp_heard_query(). Using this parameter 43 * to identify the multicast router version 44 * and do what the IGMP version 2 specified. 45 * Chih-Jen Chang : Added a timer to revert to IGMP V2 router 46 * Tsu-Sheng Tsao if the specified time expired. 47 * Alan Cox : Stop IGMP from 0.0.0.0 being accepted. 48 * Alan Cox : Use GFP_ATOMIC in the right places. 49 * Christian Daudt : igmp timer wasn't set for local group 50 * memberships but was being deleted, 51 * which caused a "del_timer() called 52 * from %p with timer not initialized\n" 53 * message (960131). 54 * Christian Daudt : removed del_timer from 55 * igmp_timer_expire function (960205). 56 * Christian Daudt : igmp_heard_report now only calls 57 * igmp_timer_expire if tm->running is 58 * true (960216). 59 * Malcolm Beattie : ttl comparison wrong in igmp_rcv made 60 * igmp_heard_query never trigger. Expiry 61 * miscalculation fixed in igmp_heard_query 62 * and random() made to return unsigned to 63 * prevent negative expiry times. 64 * Alexey Kuznetsov: Wrong group leaving behaviour, backport 65 * fix from pending 2.1.x patches. 66 * Alan Cox: Forget to enable FDDI support earlier. 67 * Alexey Kuznetsov: Fixed leaving groups on device down. 68 * Alexey Kuznetsov: Accordance to igmp-v2-06 draft. 69 * David L Stevens: IGMPv3 support, with help from 70 * Vinay Kulkarni 71 */ 72 73 #include <linux/module.h> 74 #include <linux/slab.h> 75 #include <asm/uaccess.h> 76 #include <linux/types.h> 77 #include <linux/kernel.h> 78 #include <linux/jiffies.h> 79 #include <linux/string.h> 80 #include <linux/socket.h> 81 #include <linux/sockios.h> 82 #include <linux/in.h> 83 #include <linux/inet.h> 84 #include <linux/netdevice.h> 85 #include <linux/skbuff.h> 86 #include <linux/inetdevice.h> 87 #include <linux/igmp.h> 88 #include <linux/if_arp.h> 89 #include <linux/rtnetlink.h> 90 #include <linux/times.h> 91 #include <linux/pkt_sched.h> 92 93 #include <net/net_namespace.h> 94 #include <net/arp.h> 95 #include <net/ip.h> 96 #include <net/protocol.h> 97 #include <net/route.h> 98 #include <net/sock.h> 99 #include <net/checksum.h> 100 #include <net/inet_common.h> 101 #include <linux/netfilter_ipv4.h> 102 #ifdef CONFIG_IP_MROUTE 103 #include <linux/mroute.h> 104 #endif 105 #ifdef CONFIG_PROC_FS 106 #include <linux/proc_fs.h> 107 #include <linux/seq_file.h> 108 #endif 109 110 #ifdef CONFIG_IP_MULTICAST 111 /* Parameter names and values are taken from igmp-v2-06 draft */ 112 113 #define IGMP_V1_ROUTER_PRESENT_TIMEOUT (400*HZ) 114 #define IGMP_V2_ROUTER_PRESENT_TIMEOUT (400*HZ) 115 #define IGMP_V2_UNSOLICITED_REPORT_INTERVAL (10*HZ) 116 #define IGMP_V3_UNSOLICITED_REPORT_INTERVAL (1*HZ) 117 #define IGMP_QUERY_RESPONSE_INTERVAL (10*HZ) 118 #define IGMP_QUERY_ROBUSTNESS_VARIABLE 2 119 120 121 #define IGMP_INITIAL_REPORT_DELAY (1) 122 123 /* IGMP_INITIAL_REPORT_DELAY is not from IGMP specs! 124 * IGMP specs require to report membership immediately after 125 * joining a group, but we delay the first report by a 126 * small interval. It seems more natural and still does not 127 * contradict to specs provided this delay is small enough. 128 */ 129 130 #define IGMP_V1_SEEN(in_dev) \ 131 (IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \ 132 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \ 133 ((in_dev)->mr_v1_seen && \ 134 time_before(jiffies, (in_dev)->mr_v1_seen))) 135 #define IGMP_V2_SEEN(in_dev) \ 136 (IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \ 137 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \ 138 ((in_dev)->mr_v2_seen && \ 139 time_before(jiffies, (in_dev)->mr_v2_seen))) 140 141 static int unsolicited_report_interval(struct in_device *in_dev) 142 { 143 int interval_ms, interval_jiffies; 144 145 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) 146 interval_ms = IN_DEV_CONF_GET( 147 in_dev, 148 IGMPV2_UNSOLICITED_REPORT_INTERVAL); 149 else /* v3 */ 150 interval_ms = IN_DEV_CONF_GET( 151 in_dev, 152 IGMPV3_UNSOLICITED_REPORT_INTERVAL); 153 154 interval_jiffies = msecs_to_jiffies(interval_ms); 155 156 /* _timer functions can't handle a delay of 0 jiffies so ensure 157 * we always return a positive value. 158 */ 159 if (interval_jiffies <= 0) 160 interval_jiffies = 1; 161 return interval_jiffies; 162 } 163 164 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im); 165 static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr); 166 static void igmpv3_clear_delrec(struct in_device *in_dev); 167 static int sf_setstate(struct ip_mc_list *pmc); 168 static void sf_markstate(struct ip_mc_list *pmc); 169 #endif 170 static void ip_mc_clear_src(struct ip_mc_list *pmc); 171 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 172 int sfcount, __be32 *psfsrc, int delta); 173 174 static void ip_ma_put(struct ip_mc_list *im) 175 { 176 if (atomic_dec_and_test(&im->refcnt)) { 177 in_dev_put(im->interface); 178 kfree_rcu(im, rcu); 179 } 180 } 181 182 #define for_each_pmc_rcu(in_dev, pmc) \ 183 for (pmc = rcu_dereference(in_dev->mc_list); \ 184 pmc != NULL; \ 185 pmc = rcu_dereference(pmc->next_rcu)) 186 187 #define for_each_pmc_rtnl(in_dev, pmc) \ 188 for (pmc = rtnl_dereference(in_dev->mc_list); \ 189 pmc != NULL; \ 190 pmc = rtnl_dereference(pmc->next_rcu)) 191 192 #ifdef CONFIG_IP_MULTICAST 193 194 /* 195 * Timer management 196 */ 197 198 static void igmp_stop_timer(struct ip_mc_list *im) 199 { 200 spin_lock_bh(&im->lock); 201 if (del_timer(&im->timer)) 202 atomic_dec(&im->refcnt); 203 im->tm_running = 0; 204 im->reporter = 0; 205 im->unsolicit_count = 0; 206 spin_unlock_bh(&im->lock); 207 } 208 209 /* It must be called with locked im->lock */ 210 static void igmp_start_timer(struct ip_mc_list *im, int max_delay) 211 { 212 int tv = prandom_u32() % max_delay; 213 214 im->tm_running = 1; 215 if (!mod_timer(&im->timer, jiffies+tv+2)) 216 atomic_inc(&im->refcnt); 217 } 218 219 static void igmp_gq_start_timer(struct in_device *in_dev) 220 { 221 int tv = prandom_u32() % in_dev->mr_maxdelay; 222 223 in_dev->mr_gq_running = 1; 224 if (!mod_timer(&in_dev->mr_gq_timer, jiffies+tv+2)) 225 in_dev_hold(in_dev); 226 } 227 228 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay) 229 { 230 int tv = prandom_u32() % delay; 231 232 if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2)) 233 in_dev_hold(in_dev); 234 } 235 236 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay) 237 { 238 spin_lock_bh(&im->lock); 239 im->unsolicit_count = 0; 240 if (del_timer(&im->timer)) { 241 if ((long)(im->timer.expires-jiffies) < max_delay) { 242 add_timer(&im->timer); 243 im->tm_running = 1; 244 spin_unlock_bh(&im->lock); 245 return; 246 } 247 atomic_dec(&im->refcnt); 248 } 249 igmp_start_timer(im, max_delay); 250 spin_unlock_bh(&im->lock); 251 } 252 253 254 /* 255 * Send an IGMP report. 256 */ 257 258 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4) 259 260 261 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type, 262 int gdeleted, int sdeleted) 263 { 264 switch (type) { 265 case IGMPV3_MODE_IS_INCLUDE: 266 case IGMPV3_MODE_IS_EXCLUDE: 267 if (gdeleted || sdeleted) 268 return 0; 269 if (!(pmc->gsquery && !psf->sf_gsresp)) { 270 if (pmc->sfmode == MCAST_INCLUDE) 271 return 1; 272 /* don't include if this source is excluded 273 * in all filters 274 */ 275 if (psf->sf_count[MCAST_INCLUDE]) 276 return type == IGMPV3_MODE_IS_INCLUDE; 277 return pmc->sfcount[MCAST_EXCLUDE] == 278 psf->sf_count[MCAST_EXCLUDE]; 279 } 280 return 0; 281 case IGMPV3_CHANGE_TO_INCLUDE: 282 if (gdeleted || sdeleted) 283 return 0; 284 return psf->sf_count[MCAST_INCLUDE] != 0; 285 case IGMPV3_CHANGE_TO_EXCLUDE: 286 if (gdeleted || sdeleted) 287 return 0; 288 if (pmc->sfcount[MCAST_EXCLUDE] == 0 || 289 psf->sf_count[MCAST_INCLUDE]) 290 return 0; 291 return pmc->sfcount[MCAST_EXCLUDE] == 292 psf->sf_count[MCAST_EXCLUDE]; 293 case IGMPV3_ALLOW_NEW_SOURCES: 294 if (gdeleted || !psf->sf_crcount) 295 return 0; 296 return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted; 297 case IGMPV3_BLOCK_OLD_SOURCES: 298 if (pmc->sfmode == MCAST_INCLUDE) 299 return gdeleted || (psf->sf_crcount && sdeleted); 300 return psf->sf_crcount && !gdeleted && !sdeleted; 301 } 302 return 0; 303 } 304 305 static int 306 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted) 307 { 308 struct ip_sf_list *psf; 309 int scount = 0; 310 311 for (psf = pmc->sources; psf; psf = psf->sf_next) { 312 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) 313 continue; 314 scount++; 315 } 316 return scount; 317 } 318 319 static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu) 320 { 321 struct sk_buff *skb; 322 struct rtable *rt; 323 struct iphdr *pip; 324 struct igmpv3_report *pig; 325 struct net *net = dev_net(dev); 326 struct flowi4 fl4; 327 int hlen = LL_RESERVED_SPACE(dev); 328 int tlen = dev->needed_tailroom; 329 unsigned int size = mtu; 330 331 while (1) { 332 skb = alloc_skb(size + hlen + tlen, 333 GFP_ATOMIC | __GFP_NOWARN); 334 if (skb) 335 break; 336 size >>= 1; 337 if (size < 256) 338 return NULL; 339 } 340 skb->priority = TC_PRIO_CONTROL; 341 342 rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0, 343 0, 0, 344 IPPROTO_IGMP, 0, dev->ifindex); 345 if (IS_ERR(rt)) { 346 kfree_skb(skb); 347 return NULL; 348 } 349 350 skb_dst_set(skb, &rt->dst); 351 skb->dev = dev; 352 353 skb_reserve(skb, hlen); 354 skb_tailroom_reserve(skb, mtu, tlen); 355 356 skb_reset_network_header(skb); 357 pip = ip_hdr(skb); 358 skb_put(skb, sizeof(struct iphdr) + 4); 359 360 pip->version = 4; 361 pip->ihl = (sizeof(struct iphdr)+4)>>2; 362 pip->tos = 0xc0; 363 pip->frag_off = htons(IP_DF); 364 pip->ttl = 1; 365 pip->daddr = fl4.daddr; 366 pip->saddr = fl4.saddr; 367 pip->protocol = IPPROTO_IGMP; 368 pip->tot_len = 0; /* filled in later */ 369 ip_select_ident(net, skb, NULL); 370 ((u8 *)&pip[1])[0] = IPOPT_RA; 371 ((u8 *)&pip[1])[1] = 4; 372 ((u8 *)&pip[1])[2] = 0; 373 ((u8 *)&pip[1])[3] = 0; 374 375 skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4; 376 skb_put(skb, sizeof(*pig)); 377 pig = igmpv3_report_hdr(skb); 378 pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT; 379 pig->resv1 = 0; 380 pig->csum = 0; 381 pig->resv2 = 0; 382 pig->ngrec = 0; 383 return skb; 384 } 385 386 static int igmpv3_sendpack(struct sk_buff *skb) 387 { 388 struct igmphdr *pig = igmp_hdr(skb); 389 const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb); 390 391 pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen); 392 393 return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb); 394 } 395 396 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel) 397 { 398 return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel); 399 } 400 401 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc, 402 int type, struct igmpv3_grec **ppgr) 403 { 404 struct net_device *dev = pmc->interface->dev; 405 struct igmpv3_report *pih; 406 struct igmpv3_grec *pgr; 407 408 if (!skb) 409 skb = igmpv3_newpack(dev, dev->mtu); 410 if (!skb) 411 return NULL; 412 pgr = (struct igmpv3_grec *)skb_put(skb, sizeof(struct igmpv3_grec)); 413 pgr->grec_type = type; 414 pgr->grec_auxwords = 0; 415 pgr->grec_nsrcs = 0; 416 pgr->grec_mca = pmc->multiaddr; 417 pih = igmpv3_report_hdr(skb); 418 pih->ngrec = htons(ntohs(pih->ngrec)+1); 419 *ppgr = pgr; 420 return skb; 421 } 422 423 #define AVAILABLE(skb) ((skb) ? skb_availroom(skb) : 0) 424 425 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc, 426 int type, int gdeleted, int sdeleted) 427 { 428 struct net_device *dev = pmc->interface->dev; 429 struct net *net = dev_net(dev); 430 struct igmpv3_report *pih; 431 struct igmpv3_grec *pgr = NULL; 432 struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list; 433 int scount, stotal, first, isquery, truncate; 434 435 if (pmc->multiaddr == IGMP_ALL_HOSTS) 436 return skb; 437 if (ipv4_is_local_multicast(pmc->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports) 438 return skb; 439 440 isquery = type == IGMPV3_MODE_IS_INCLUDE || 441 type == IGMPV3_MODE_IS_EXCLUDE; 442 truncate = type == IGMPV3_MODE_IS_EXCLUDE || 443 type == IGMPV3_CHANGE_TO_EXCLUDE; 444 445 stotal = scount = 0; 446 447 psf_list = sdeleted ? &pmc->tomb : &pmc->sources; 448 449 if (!*psf_list) 450 goto empty_source; 451 452 pih = skb ? igmpv3_report_hdr(skb) : NULL; 453 454 /* EX and TO_EX get a fresh packet, if needed */ 455 if (truncate) { 456 if (pih && pih->ngrec && 457 AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) { 458 if (skb) 459 igmpv3_sendpack(skb); 460 skb = igmpv3_newpack(dev, dev->mtu); 461 } 462 } 463 first = 1; 464 psf_prev = NULL; 465 for (psf = *psf_list; psf; psf = psf_next) { 466 __be32 *psrc; 467 468 psf_next = psf->sf_next; 469 470 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) { 471 psf_prev = psf; 472 continue; 473 } 474 475 /* Based on RFC3376 5.1. Should not send source-list change 476 * records when there is a filter mode change. 477 */ 478 if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) || 479 (!gdeleted && pmc->crcount)) && 480 (type == IGMPV3_ALLOW_NEW_SOURCES || 481 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) 482 goto decrease_sf_crcount; 483 484 /* clear marks on query responses */ 485 if (isquery) 486 psf->sf_gsresp = 0; 487 488 if (AVAILABLE(skb) < sizeof(__be32) + 489 first*sizeof(struct igmpv3_grec)) { 490 if (truncate && !first) 491 break; /* truncate these */ 492 if (pgr) 493 pgr->grec_nsrcs = htons(scount); 494 if (skb) 495 igmpv3_sendpack(skb); 496 skb = igmpv3_newpack(dev, dev->mtu); 497 first = 1; 498 scount = 0; 499 } 500 if (first) { 501 skb = add_grhead(skb, pmc, type, &pgr); 502 first = 0; 503 } 504 if (!skb) 505 return NULL; 506 psrc = (__be32 *)skb_put(skb, sizeof(__be32)); 507 *psrc = psf->sf_inaddr; 508 scount++; stotal++; 509 if ((type == IGMPV3_ALLOW_NEW_SOURCES || 510 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) { 511 decrease_sf_crcount: 512 psf->sf_crcount--; 513 if ((sdeleted || gdeleted) && psf->sf_crcount == 0) { 514 if (psf_prev) 515 psf_prev->sf_next = psf->sf_next; 516 else 517 *psf_list = psf->sf_next; 518 kfree(psf); 519 continue; 520 } 521 } 522 psf_prev = psf; 523 } 524 525 empty_source: 526 if (!stotal) { 527 if (type == IGMPV3_ALLOW_NEW_SOURCES || 528 type == IGMPV3_BLOCK_OLD_SOURCES) 529 return skb; 530 if (pmc->crcount || isquery) { 531 /* make sure we have room for group header */ 532 if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) { 533 igmpv3_sendpack(skb); 534 skb = NULL; /* add_grhead will get a new one */ 535 } 536 skb = add_grhead(skb, pmc, type, &pgr); 537 } 538 } 539 if (pgr) 540 pgr->grec_nsrcs = htons(scount); 541 542 if (isquery) 543 pmc->gsquery = 0; /* clear query state on report */ 544 return skb; 545 } 546 547 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc) 548 { 549 struct sk_buff *skb = NULL; 550 struct net *net = dev_net(in_dev->dev); 551 int type; 552 553 if (!pmc) { 554 rcu_read_lock(); 555 for_each_pmc_rcu(in_dev, pmc) { 556 if (pmc->multiaddr == IGMP_ALL_HOSTS) 557 continue; 558 if (ipv4_is_local_multicast(pmc->multiaddr) && 559 !net->ipv4.sysctl_igmp_llm_reports) 560 continue; 561 spin_lock_bh(&pmc->lock); 562 if (pmc->sfcount[MCAST_EXCLUDE]) 563 type = IGMPV3_MODE_IS_EXCLUDE; 564 else 565 type = IGMPV3_MODE_IS_INCLUDE; 566 skb = add_grec(skb, pmc, type, 0, 0); 567 spin_unlock_bh(&pmc->lock); 568 } 569 rcu_read_unlock(); 570 } else { 571 spin_lock_bh(&pmc->lock); 572 if (pmc->sfcount[MCAST_EXCLUDE]) 573 type = IGMPV3_MODE_IS_EXCLUDE; 574 else 575 type = IGMPV3_MODE_IS_INCLUDE; 576 skb = add_grec(skb, pmc, type, 0, 0); 577 spin_unlock_bh(&pmc->lock); 578 } 579 if (!skb) 580 return 0; 581 return igmpv3_sendpack(skb); 582 } 583 584 /* 585 * remove zero-count source records from a source filter list 586 */ 587 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf) 588 { 589 struct ip_sf_list *psf_prev, *psf_next, *psf; 590 591 psf_prev = NULL; 592 for (psf = *ppsf; psf; psf = psf_next) { 593 psf_next = psf->sf_next; 594 if (psf->sf_crcount == 0) { 595 if (psf_prev) 596 psf_prev->sf_next = psf->sf_next; 597 else 598 *ppsf = psf->sf_next; 599 kfree(psf); 600 } else 601 psf_prev = psf; 602 } 603 } 604 605 static void igmpv3_send_cr(struct in_device *in_dev) 606 { 607 struct ip_mc_list *pmc, *pmc_prev, *pmc_next; 608 struct sk_buff *skb = NULL; 609 int type, dtype; 610 611 rcu_read_lock(); 612 spin_lock_bh(&in_dev->mc_tomb_lock); 613 614 /* deleted MCA's */ 615 pmc_prev = NULL; 616 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) { 617 pmc_next = pmc->next; 618 if (pmc->sfmode == MCAST_INCLUDE) { 619 type = IGMPV3_BLOCK_OLD_SOURCES; 620 dtype = IGMPV3_BLOCK_OLD_SOURCES; 621 skb = add_grec(skb, pmc, type, 1, 0); 622 skb = add_grec(skb, pmc, dtype, 1, 1); 623 } 624 if (pmc->crcount) { 625 if (pmc->sfmode == MCAST_EXCLUDE) { 626 type = IGMPV3_CHANGE_TO_INCLUDE; 627 skb = add_grec(skb, pmc, type, 1, 0); 628 } 629 pmc->crcount--; 630 if (pmc->crcount == 0) { 631 igmpv3_clear_zeros(&pmc->tomb); 632 igmpv3_clear_zeros(&pmc->sources); 633 } 634 } 635 if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) { 636 if (pmc_prev) 637 pmc_prev->next = pmc_next; 638 else 639 in_dev->mc_tomb = pmc_next; 640 in_dev_put(pmc->interface); 641 kfree(pmc); 642 } else 643 pmc_prev = pmc; 644 } 645 spin_unlock_bh(&in_dev->mc_tomb_lock); 646 647 /* change recs */ 648 for_each_pmc_rcu(in_dev, pmc) { 649 spin_lock_bh(&pmc->lock); 650 if (pmc->sfcount[MCAST_EXCLUDE]) { 651 type = IGMPV3_BLOCK_OLD_SOURCES; 652 dtype = IGMPV3_ALLOW_NEW_SOURCES; 653 } else { 654 type = IGMPV3_ALLOW_NEW_SOURCES; 655 dtype = IGMPV3_BLOCK_OLD_SOURCES; 656 } 657 skb = add_grec(skb, pmc, type, 0, 0); 658 skb = add_grec(skb, pmc, dtype, 0, 1); /* deleted sources */ 659 660 /* filter mode changes */ 661 if (pmc->crcount) { 662 if (pmc->sfmode == MCAST_EXCLUDE) 663 type = IGMPV3_CHANGE_TO_EXCLUDE; 664 else 665 type = IGMPV3_CHANGE_TO_INCLUDE; 666 skb = add_grec(skb, pmc, type, 0, 0); 667 pmc->crcount--; 668 } 669 spin_unlock_bh(&pmc->lock); 670 } 671 rcu_read_unlock(); 672 673 if (!skb) 674 return; 675 (void) igmpv3_sendpack(skb); 676 } 677 678 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc, 679 int type) 680 { 681 struct sk_buff *skb; 682 struct iphdr *iph; 683 struct igmphdr *ih; 684 struct rtable *rt; 685 struct net_device *dev = in_dev->dev; 686 struct net *net = dev_net(dev); 687 __be32 group = pmc ? pmc->multiaddr : 0; 688 struct flowi4 fl4; 689 __be32 dst; 690 int hlen, tlen; 691 692 if (type == IGMPV3_HOST_MEMBERSHIP_REPORT) 693 return igmpv3_send_report(in_dev, pmc); 694 695 if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports) 696 return 0; 697 698 if (type == IGMP_HOST_LEAVE_MESSAGE) 699 dst = IGMP_ALL_ROUTER; 700 else 701 dst = group; 702 703 rt = ip_route_output_ports(net, &fl4, NULL, dst, 0, 704 0, 0, 705 IPPROTO_IGMP, 0, dev->ifindex); 706 if (IS_ERR(rt)) 707 return -1; 708 709 hlen = LL_RESERVED_SPACE(dev); 710 tlen = dev->needed_tailroom; 711 skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC); 712 if (!skb) { 713 ip_rt_put(rt); 714 return -1; 715 } 716 skb->priority = TC_PRIO_CONTROL; 717 718 skb_dst_set(skb, &rt->dst); 719 720 skb_reserve(skb, hlen); 721 722 skb_reset_network_header(skb); 723 iph = ip_hdr(skb); 724 skb_put(skb, sizeof(struct iphdr) + 4); 725 726 iph->version = 4; 727 iph->ihl = (sizeof(struct iphdr)+4)>>2; 728 iph->tos = 0xc0; 729 iph->frag_off = htons(IP_DF); 730 iph->ttl = 1; 731 iph->daddr = dst; 732 iph->saddr = fl4.saddr; 733 iph->protocol = IPPROTO_IGMP; 734 ip_select_ident(net, skb, NULL); 735 ((u8 *)&iph[1])[0] = IPOPT_RA; 736 ((u8 *)&iph[1])[1] = 4; 737 ((u8 *)&iph[1])[2] = 0; 738 ((u8 *)&iph[1])[3] = 0; 739 740 ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr)); 741 ih->type = type; 742 ih->code = 0; 743 ih->csum = 0; 744 ih->group = group; 745 ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr)); 746 747 return ip_local_out(net, skb->sk, skb); 748 } 749 750 static void igmp_gq_timer_expire(unsigned long data) 751 { 752 struct in_device *in_dev = (struct in_device *)data; 753 754 in_dev->mr_gq_running = 0; 755 igmpv3_send_report(in_dev, NULL); 756 in_dev_put(in_dev); 757 } 758 759 static void igmp_ifc_timer_expire(unsigned long data) 760 { 761 struct in_device *in_dev = (struct in_device *)data; 762 763 igmpv3_send_cr(in_dev); 764 if (in_dev->mr_ifc_count) { 765 in_dev->mr_ifc_count--; 766 igmp_ifc_start_timer(in_dev, 767 unsolicited_report_interval(in_dev)); 768 } 769 in_dev_put(in_dev); 770 } 771 772 static void igmp_ifc_event(struct in_device *in_dev) 773 { 774 struct net *net = dev_net(in_dev->dev); 775 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) 776 return; 777 in_dev->mr_ifc_count = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 778 igmp_ifc_start_timer(in_dev, 1); 779 } 780 781 782 static void igmp_timer_expire(unsigned long data) 783 { 784 struct ip_mc_list *im = (struct ip_mc_list *)data; 785 struct in_device *in_dev = im->interface; 786 787 spin_lock(&im->lock); 788 im->tm_running = 0; 789 790 if (im->unsolicit_count) { 791 im->unsolicit_count--; 792 igmp_start_timer(im, unsolicited_report_interval(in_dev)); 793 } 794 im->reporter = 1; 795 spin_unlock(&im->lock); 796 797 if (IGMP_V1_SEEN(in_dev)) 798 igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT); 799 else if (IGMP_V2_SEEN(in_dev)) 800 igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT); 801 else 802 igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT); 803 804 ip_ma_put(im); 805 } 806 807 /* mark EXCLUDE-mode sources */ 808 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs) 809 { 810 struct ip_sf_list *psf; 811 int i, scount; 812 813 scount = 0; 814 for (psf = pmc->sources; psf; psf = psf->sf_next) { 815 if (scount == nsrcs) 816 break; 817 for (i = 0; i < nsrcs; i++) { 818 /* skip inactive filters */ 819 if (psf->sf_count[MCAST_INCLUDE] || 820 pmc->sfcount[MCAST_EXCLUDE] != 821 psf->sf_count[MCAST_EXCLUDE]) 822 break; 823 if (srcs[i] == psf->sf_inaddr) { 824 scount++; 825 break; 826 } 827 } 828 } 829 pmc->gsquery = 0; 830 if (scount == nsrcs) /* all sources excluded */ 831 return 0; 832 return 1; 833 } 834 835 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs) 836 { 837 struct ip_sf_list *psf; 838 int i, scount; 839 840 if (pmc->sfmode == MCAST_EXCLUDE) 841 return igmp_xmarksources(pmc, nsrcs, srcs); 842 843 /* mark INCLUDE-mode sources */ 844 scount = 0; 845 for (psf = pmc->sources; psf; psf = psf->sf_next) { 846 if (scount == nsrcs) 847 break; 848 for (i = 0; i < nsrcs; i++) 849 if (srcs[i] == psf->sf_inaddr) { 850 psf->sf_gsresp = 1; 851 scount++; 852 break; 853 } 854 } 855 if (!scount) { 856 pmc->gsquery = 0; 857 return 0; 858 } 859 pmc->gsquery = 1; 860 return 1; 861 } 862 863 /* return true if packet was dropped */ 864 static bool igmp_heard_report(struct in_device *in_dev, __be32 group) 865 { 866 struct ip_mc_list *im; 867 struct net *net = dev_net(in_dev->dev); 868 869 /* Timers are only set for non-local groups */ 870 871 if (group == IGMP_ALL_HOSTS) 872 return false; 873 if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports) 874 return false; 875 876 rcu_read_lock(); 877 for_each_pmc_rcu(in_dev, im) { 878 if (im->multiaddr == group) { 879 igmp_stop_timer(im); 880 break; 881 } 882 } 883 rcu_read_unlock(); 884 return false; 885 } 886 887 /* return true if packet was dropped */ 888 static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb, 889 int len) 890 { 891 struct igmphdr *ih = igmp_hdr(skb); 892 struct igmpv3_query *ih3 = igmpv3_query_hdr(skb); 893 struct ip_mc_list *im; 894 __be32 group = ih->group; 895 int max_delay; 896 int mark = 0; 897 struct net *net = dev_net(in_dev->dev); 898 899 900 if (len == 8) { 901 if (ih->code == 0) { 902 /* Alas, old v1 router presents here. */ 903 904 max_delay = IGMP_QUERY_RESPONSE_INTERVAL; 905 in_dev->mr_v1_seen = jiffies + 906 IGMP_V1_ROUTER_PRESENT_TIMEOUT; 907 group = 0; 908 } else { 909 /* v2 router present */ 910 max_delay = ih->code*(HZ/IGMP_TIMER_SCALE); 911 in_dev->mr_v2_seen = jiffies + 912 IGMP_V2_ROUTER_PRESENT_TIMEOUT; 913 } 914 /* cancel the interface change timer */ 915 in_dev->mr_ifc_count = 0; 916 if (del_timer(&in_dev->mr_ifc_timer)) 917 __in_dev_put(in_dev); 918 /* clear deleted report items */ 919 igmpv3_clear_delrec(in_dev); 920 } else if (len < 12) { 921 return true; /* ignore bogus packet; freed by caller */ 922 } else if (IGMP_V1_SEEN(in_dev)) { 923 /* This is a v3 query with v1 queriers present */ 924 max_delay = IGMP_QUERY_RESPONSE_INTERVAL; 925 group = 0; 926 } else if (IGMP_V2_SEEN(in_dev)) { 927 /* this is a v3 query with v2 queriers present; 928 * Interpretation of the max_delay code is problematic here. 929 * A real v2 host would use ih_code directly, while v3 has a 930 * different encoding. We use the v3 encoding as more likely 931 * to be intended in a v3 query. 932 */ 933 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE); 934 if (!max_delay) 935 max_delay = 1; /* can't mod w/ 0 */ 936 } else { /* v3 */ 937 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) 938 return true; 939 940 ih3 = igmpv3_query_hdr(skb); 941 if (ih3->nsrcs) { 942 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query) 943 + ntohs(ih3->nsrcs)*sizeof(__be32))) 944 return true; 945 ih3 = igmpv3_query_hdr(skb); 946 } 947 948 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE); 949 if (!max_delay) 950 max_delay = 1; /* can't mod w/ 0 */ 951 in_dev->mr_maxdelay = max_delay; 952 if (ih3->qrv) 953 in_dev->mr_qrv = ih3->qrv; 954 if (!group) { /* general query */ 955 if (ih3->nsrcs) 956 return true; /* no sources allowed */ 957 igmp_gq_start_timer(in_dev); 958 return false; 959 } 960 /* mark sources to include, if group & source-specific */ 961 mark = ih3->nsrcs != 0; 962 } 963 964 /* 965 * - Start the timers in all of our membership records 966 * that the query applies to for the interface on 967 * which the query arrived excl. those that belong 968 * to a "local" group (224.0.0.X) 969 * - For timers already running check if they need to 970 * be reset. 971 * - Use the igmp->igmp_code field as the maximum 972 * delay possible 973 */ 974 rcu_read_lock(); 975 for_each_pmc_rcu(in_dev, im) { 976 int changed; 977 978 if (group && group != im->multiaddr) 979 continue; 980 if (im->multiaddr == IGMP_ALL_HOSTS) 981 continue; 982 if (ipv4_is_local_multicast(im->multiaddr) && 983 !net->ipv4.sysctl_igmp_llm_reports) 984 continue; 985 spin_lock_bh(&im->lock); 986 if (im->tm_running) 987 im->gsquery = im->gsquery && mark; 988 else 989 im->gsquery = mark; 990 changed = !im->gsquery || 991 igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs); 992 spin_unlock_bh(&im->lock); 993 if (changed) 994 igmp_mod_timer(im, max_delay); 995 } 996 rcu_read_unlock(); 997 return false; 998 } 999 1000 /* called in rcu_read_lock() section */ 1001 int igmp_rcv(struct sk_buff *skb) 1002 { 1003 /* This basically follows the spec line by line -- see RFC1112 */ 1004 struct igmphdr *ih; 1005 struct in_device *in_dev = __in_dev_get_rcu(skb->dev); 1006 int len = skb->len; 1007 bool dropped = true; 1008 1009 if (!in_dev) 1010 goto drop; 1011 1012 if (!pskb_may_pull(skb, sizeof(struct igmphdr))) 1013 goto drop; 1014 1015 if (skb_checksum_simple_validate(skb)) 1016 goto drop; 1017 1018 ih = igmp_hdr(skb); 1019 switch (ih->type) { 1020 case IGMP_HOST_MEMBERSHIP_QUERY: 1021 dropped = igmp_heard_query(in_dev, skb, len); 1022 break; 1023 case IGMP_HOST_MEMBERSHIP_REPORT: 1024 case IGMPV2_HOST_MEMBERSHIP_REPORT: 1025 /* Is it our report looped back? */ 1026 if (rt_is_output_route(skb_rtable(skb))) 1027 break; 1028 /* don't rely on MC router hearing unicast reports */ 1029 if (skb->pkt_type == PACKET_MULTICAST || 1030 skb->pkt_type == PACKET_BROADCAST) 1031 dropped = igmp_heard_report(in_dev, ih->group); 1032 break; 1033 case IGMP_PIM: 1034 #ifdef CONFIG_IP_PIMSM_V1 1035 return pim_rcv_v1(skb); 1036 #endif 1037 case IGMPV3_HOST_MEMBERSHIP_REPORT: 1038 case IGMP_DVMRP: 1039 case IGMP_TRACE: 1040 case IGMP_HOST_LEAVE_MESSAGE: 1041 case IGMP_MTRACE: 1042 case IGMP_MTRACE_RESP: 1043 break; 1044 default: 1045 break; 1046 } 1047 1048 drop: 1049 if (dropped) 1050 kfree_skb(skb); 1051 else 1052 consume_skb(skb); 1053 return 0; 1054 } 1055 1056 #endif 1057 1058 1059 /* 1060 * Add a filter to a device 1061 */ 1062 1063 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr) 1064 { 1065 char buf[MAX_ADDR_LEN]; 1066 struct net_device *dev = in_dev->dev; 1067 1068 /* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG. 1069 We will get multicast token leakage, when IFF_MULTICAST 1070 is changed. This check should be done in ndo_set_rx_mode 1071 routine. Something sort of: 1072 if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; } 1073 --ANK 1074 */ 1075 if (arp_mc_map(addr, buf, dev, 0) == 0) 1076 dev_mc_add(dev, buf); 1077 } 1078 1079 /* 1080 * Remove a filter from a device 1081 */ 1082 1083 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr) 1084 { 1085 char buf[MAX_ADDR_LEN]; 1086 struct net_device *dev = in_dev->dev; 1087 1088 if (arp_mc_map(addr, buf, dev, 0) == 0) 1089 dev_mc_del(dev, buf); 1090 } 1091 1092 #ifdef CONFIG_IP_MULTICAST 1093 /* 1094 * deleted ip_mc_list manipulation 1095 */ 1096 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im) 1097 { 1098 struct ip_mc_list *pmc; 1099 struct net *net = dev_net(in_dev->dev); 1100 1101 /* this is an "ip_mc_list" for convenience; only the fields below 1102 * are actually used. In particular, the refcnt and users are not 1103 * used for management of the delete list. Using the same structure 1104 * for deleted items allows change reports to use common code with 1105 * non-deleted or query-response MCA's. 1106 */ 1107 pmc = kzalloc(sizeof(*pmc), GFP_KERNEL); 1108 if (!pmc) 1109 return; 1110 spin_lock_bh(&im->lock); 1111 pmc->interface = im->interface; 1112 in_dev_hold(in_dev); 1113 pmc->multiaddr = im->multiaddr; 1114 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1115 pmc->sfmode = im->sfmode; 1116 if (pmc->sfmode == MCAST_INCLUDE) { 1117 struct ip_sf_list *psf; 1118 1119 pmc->tomb = im->tomb; 1120 pmc->sources = im->sources; 1121 im->tomb = im->sources = NULL; 1122 for (psf = pmc->sources; psf; psf = psf->sf_next) 1123 psf->sf_crcount = pmc->crcount; 1124 } 1125 spin_unlock_bh(&im->lock); 1126 1127 spin_lock_bh(&in_dev->mc_tomb_lock); 1128 pmc->next = in_dev->mc_tomb; 1129 in_dev->mc_tomb = pmc; 1130 spin_unlock_bh(&in_dev->mc_tomb_lock); 1131 } 1132 1133 static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr) 1134 { 1135 struct ip_mc_list *pmc, *pmc_prev; 1136 struct ip_sf_list *psf, *psf_next; 1137 1138 spin_lock_bh(&in_dev->mc_tomb_lock); 1139 pmc_prev = NULL; 1140 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) { 1141 if (pmc->multiaddr == multiaddr) 1142 break; 1143 pmc_prev = pmc; 1144 } 1145 if (pmc) { 1146 if (pmc_prev) 1147 pmc_prev->next = pmc->next; 1148 else 1149 in_dev->mc_tomb = pmc->next; 1150 } 1151 spin_unlock_bh(&in_dev->mc_tomb_lock); 1152 if (pmc) { 1153 for (psf = pmc->tomb; psf; psf = psf_next) { 1154 psf_next = psf->sf_next; 1155 kfree(psf); 1156 } 1157 in_dev_put(pmc->interface); 1158 kfree(pmc); 1159 } 1160 } 1161 1162 static void igmpv3_clear_delrec(struct in_device *in_dev) 1163 { 1164 struct ip_mc_list *pmc, *nextpmc; 1165 1166 spin_lock_bh(&in_dev->mc_tomb_lock); 1167 pmc = in_dev->mc_tomb; 1168 in_dev->mc_tomb = NULL; 1169 spin_unlock_bh(&in_dev->mc_tomb_lock); 1170 1171 for (; pmc; pmc = nextpmc) { 1172 nextpmc = pmc->next; 1173 ip_mc_clear_src(pmc); 1174 in_dev_put(pmc->interface); 1175 kfree(pmc); 1176 } 1177 /* clear dead sources, too */ 1178 rcu_read_lock(); 1179 for_each_pmc_rcu(in_dev, pmc) { 1180 struct ip_sf_list *psf, *psf_next; 1181 1182 spin_lock_bh(&pmc->lock); 1183 psf = pmc->tomb; 1184 pmc->tomb = NULL; 1185 spin_unlock_bh(&pmc->lock); 1186 for (; psf; psf = psf_next) { 1187 psf_next = psf->sf_next; 1188 kfree(psf); 1189 } 1190 } 1191 rcu_read_unlock(); 1192 } 1193 #endif 1194 1195 static void igmp_group_dropped(struct ip_mc_list *im) 1196 { 1197 struct in_device *in_dev = im->interface; 1198 #ifdef CONFIG_IP_MULTICAST 1199 struct net *net = dev_net(in_dev->dev); 1200 int reporter; 1201 #endif 1202 1203 if (im->loaded) { 1204 im->loaded = 0; 1205 ip_mc_filter_del(in_dev, im->multiaddr); 1206 } 1207 1208 #ifdef CONFIG_IP_MULTICAST 1209 if (im->multiaddr == IGMP_ALL_HOSTS) 1210 return; 1211 if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports) 1212 return; 1213 1214 reporter = im->reporter; 1215 igmp_stop_timer(im); 1216 1217 if (!in_dev->dead) { 1218 if (IGMP_V1_SEEN(in_dev)) 1219 return; 1220 if (IGMP_V2_SEEN(in_dev)) { 1221 if (reporter) 1222 igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE); 1223 return; 1224 } 1225 /* IGMPv3 */ 1226 igmpv3_add_delrec(in_dev, im); 1227 1228 igmp_ifc_event(in_dev); 1229 } 1230 #endif 1231 } 1232 1233 static void igmp_group_added(struct ip_mc_list *im) 1234 { 1235 struct in_device *in_dev = im->interface; 1236 #ifdef CONFIG_IP_MULTICAST 1237 struct net *net = dev_net(in_dev->dev); 1238 #endif 1239 1240 if (im->loaded == 0) { 1241 im->loaded = 1; 1242 ip_mc_filter_add(in_dev, im->multiaddr); 1243 } 1244 1245 #ifdef CONFIG_IP_MULTICAST 1246 if (im->multiaddr == IGMP_ALL_HOSTS) 1247 return; 1248 if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports) 1249 return; 1250 1251 if (in_dev->dead) 1252 return; 1253 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) { 1254 spin_lock_bh(&im->lock); 1255 igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY); 1256 spin_unlock_bh(&im->lock); 1257 return; 1258 } 1259 /* else, v3 */ 1260 1261 im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1262 igmp_ifc_event(in_dev); 1263 #endif 1264 } 1265 1266 1267 /* 1268 * Multicast list managers 1269 */ 1270 1271 static u32 ip_mc_hash(const struct ip_mc_list *im) 1272 { 1273 return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG); 1274 } 1275 1276 static void ip_mc_hash_add(struct in_device *in_dev, 1277 struct ip_mc_list *im) 1278 { 1279 struct ip_mc_list __rcu **mc_hash; 1280 u32 hash; 1281 1282 mc_hash = rtnl_dereference(in_dev->mc_hash); 1283 if (mc_hash) { 1284 hash = ip_mc_hash(im); 1285 im->next_hash = mc_hash[hash]; 1286 rcu_assign_pointer(mc_hash[hash], im); 1287 return; 1288 } 1289 1290 /* do not use a hash table for small number of items */ 1291 if (in_dev->mc_count < 4) 1292 return; 1293 1294 mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG, 1295 GFP_KERNEL); 1296 if (!mc_hash) 1297 return; 1298 1299 for_each_pmc_rtnl(in_dev, im) { 1300 hash = ip_mc_hash(im); 1301 im->next_hash = mc_hash[hash]; 1302 RCU_INIT_POINTER(mc_hash[hash], im); 1303 } 1304 1305 rcu_assign_pointer(in_dev->mc_hash, mc_hash); 1306 } 1307 1308 static void ip_mc_hash_remove(struct in_device *in_dev, 1309 struct ip_mc_list *im) 1310 { 1311 struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash); 1312 struct ip_mc_list *aux; 1313 1314 if (!mc_hash) 1315 return; 1316 mc_hash += ip_mc_hash(im); 1317 while ((aux = rtnl_dereference(*mc_hash)) != im) 1318 mc_hash = &aux->next_hash; 1319 *mc_hash = im->next_hash; 1320 } 1321 1322 1323 /* 1324 * A socket has joined a multicast group on device dev. 1325 */ 1326 1327 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr) 1328 { 1329 struct ip_mc_list *im; 1330 #ifdef CONFIG_IP_MULTICAST 1331 struct net *net = dev_net(in_dev->dev); 1332 #endif 1333 1334 ASSERT_RTNL(); 1335 1336 for_each_pmc_rtnl(in_dev, im) { 1337 if (im->multiaddr == addr) { 1338 im->users++; 1339 ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0); 1340 goto out; 1341 } 1342 } 1343 1344 im = kzalloc(sizeof(*im), GFP_KERNEL); 1345 if (!im) 1346 goto out; 1347 1348 im->users = 1; 1349 im->interface = in_dev; 1350 in_dev_hold(in_dev); 1351 im->multiaddr = addr; 1352 /* initial mode is (EX, empty) */ 1353 im->sfmode = MCAST_EXCLUDE; 1354 im->sfcount[MCAST_EXCLUDE] = 1; 1355 atomic_set(&im->refcnt, 1); 1356 spin_lock_init(&im->lock); 1357 #ifdef CONFIG_IP_MULTICAST 1358 setup_timer(&im->timer, igmp_timer_expire, (unsigned long)im); 1359 im->unsolicit_count = net->ipv4.sysctl_igmp_qrv; 1360 #endif 1361 1362 im->next_rcu = in_dev->mc_list; 1363 in_dev->mc_count++; 1364 rcu_assign_pointer(in_dev->mc_list, im); 1365 1366 ip_mc_hash_add(in_dev, im); 1367 1368 #ifdef CONFIG_IP_MULTICAST 1369 igmpv3_del_delrec(in_dev, im->multiaddr); 1370 #endif 1371 igmp_group_added(im); 1372 if (!in_dev->dead) 1373 ip_rt_multicast_event(in_dev); 1374 out: 1375 return; 1376 } 1377 EXPORT_SYMBOL(ip_mc_inc_group); 1378 1379 static int ip_mc_check_iphdr(struct sk_buff *skb) 1380 { 1381 const struct iphdr *iph; 1382 unsigned int len; 1383 unsigned int offset = skb_network_offset(skb) + sizeof(*iph); 1384 1385 if (!pskb_may_pull(skb, offset)) 1386 return -EINVAL; 1387 1388 iph = ip_hdr(skb); 1389 1390 if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph)) 1391 return -EINVAL; 1392 1393 offset += ip_hdrlen(skb) - sizeof(*iph); 1394 1395 if (!pskb_may_pull(skb, offset)) 1396 return -EINVAL; 1397 1398 iph = ip_hdr(skb); 1399 1400 if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl))) 1401 return -EINVAL; 1402 1403 len = skb_network_offset(skb) + ntohs(iph->tot_len); 1404 if (skb->len < len || len < offset) 1405 return -EINVAL; 1406 1407 skb_set_transport_header(skb, offset); 1408 1409 return 0; 1410 } 1411 1412 static int ip_mc_check_igmp_reportv3(struct sk_buff *skb) 1413 { 1414 unsigned int len = skb_transport_offset(skb); 1415 1416 len += sizeof(struct igmpv3_report); 1417 1418 return pskb_may_pull(skb, len) ? 0 : -EINVAL; 1419 } 1420 1421 static int ip_mc_check_igmp_query(struct sk_buff *skb) 1422 { 1423 unsigned int len = skb_transport_offset(skb); 1424 1425 len += sizeof(struct igmphdr); 1426 if (skb->len < len) 1427 return -EINVAL; 1428 1429 /* IGMPv{1,2}? */ 1430 if (skb->len != len) { 1431 /* or IGMPv3? */ 1432 len += sizeof(struct igmpv3_query) - sizeof(struct igmphdr); 1433 if (skb->len < len || !pskb_may_pull(skb, len)) 1434 return -EINVAL; 1435 } 1436 1437 /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer 1438 * all-systems destination addresses (224.0.0.1) for general queries 1439 */ 1440 if (!igmp_hdr(skb)->group && 1441 ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP)) 1442 return -EINVAL; 1443 1444 return 0; 1445 } 1446 1447 static int ip_mc_check_igmp_msg(struct sk_buff *skb) 1448 { 1449 switch (igmp_hdr(skb)->type) { 1450 case IGMP_HOST_LEAVE_MESSAGE: 1451 case IGMP_HOST_MEMBERSHIP_REPORT: 1452 case IGMPV2_HOST_MEMBERSHIP_REPORT: 1453 /* fall through */ 1454 return 0; 1455 case IGMPV3_HOST_MEMBERSHIP_REPORT: 1456 return ip_mc_check_igmp_reportv3(skb); 1457 case IGMP_HOST_MEMBERSHIP_QUERY: 1458 return ip_mc_check_igmp_query(skb); 1459 default: 1460 return -ENOMSG; 1461 } 1462 } 1463 1464 static inline __sum16 ip_mc_validate_checksum(struct sk_buff *skb) 1465 { 1466 return skb_checksum_simple_validate(skb); 1467 } 1468 1469 static int __ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed) 1470 1471 { 1472 struct sk_buff *skb_chk; 1473 unsigned int transport_len; 1474 unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr); 1475 int ret = -EINVAL; 1476 1477 transport_len = ntohs(ip_hdr(skb)->tot_len) - ip_hdrlen(skb); 1478 1479 skb_chk = skb_checksum_trimmed(skb, transport_len, 1480 ip_mc_validate_checksum); 1481 if (!skb_chk) 1482 goto err; 1483 1484 if (!pskb_may_pull(skb_chk, len)) 1485 goto err; 1486 1487 ret = ip_mc_check_igmp_msg(skb_chk); 1488 if (ret) 1489 goto err; 1490 1491 if (skb_trimmed) 1492 *skb_trimmed = skb_chk; 1493 /* free now unneeded clone */ 1494 else if (skb_chk != skb) 1495 kfree_skb(skb_chk); 1496 1497 ret = 0; 1498 1499 err: 1500 if (ret && skb_chk && skb_chk != skb) 1501 kfree_skb(skb_chk); 1502 1503 return ret; 1504 } 1505 1506 /** 1507 * ip_mc_check_igmp - checks whether this is a sane IGMP packet 1508 * @skb: the skb to validate 1509 * @skb_trimmed: to store an skb pointer trimmed to IPv4 packet tail (optional) 1510 * 1511 * Checks whether an IPv4 packet is a valid IGMP packet. If so sets 1512 * skb transport header accordingly and returns zero. 1513 * 1514 * -EINVAL: A broken packet was detected, i.e. it violates some internet 1515 * standard 1516 * -ENOMSG: IP header validation succeeded but it is not an IGMP packet. 1517 * -ENOMEM: A memory allocation failure happened. 1518 * 1519 * Optionally, an skb pointer might be provided via skb_trimmed (or set it 1520 * to NULL): After parsing an IGMP packet successfully it will point to 1521 * an skb which has its tail aligned to the IP packet end. This might 1522 * either be the originally provided skb or a trimmed, cloned version if 1523 * the skb frame had data beyond the IP packet. A cloned skb allows us 1524 * to leave the original skb and its full frame unchanged (which might be 1525 * desirable for layer 2 frame jugglers). 1526 * 1527 * Caller needs to set the skb network header and free any returned skb if it 1528 * differs from the provided skb. 1529 */ 1530 int ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed) 1531 { 1532 int ret = ip_mc_check_iphdr(skb); 1533 1534 if (ret < 0) 1535 return ret; 1536 1537 if (ip_hdr(skb)->protocol != IPPROTO_IGMP) 1538 return -ENOMSG; 1539 1540 return __ip_mc_check_igmp(skb, skb_trimmed); 1541 } 1542 EXPORT_SYMBOL(ip_mc_check_igmp); 1543 1544 /* 1545 * Resend IGMP JOIN report; used by netdev notifier. 1546 */ 1547 static void ip_mc_rejoin_groups(struct in_device *in_dev) 1548 { 1549 #ifdef CONFIG_IP_MULTICAST 1550 struct ip_mc_list *im; 1551 int type; 1552 struct net *net = dev_net(in_dev->dev); 1553 1554 ASSERT_RTNL(); 1555 1556 for_each_pmc_rtnl(in_dev, im) { 1557 if (im->multiaddr == IGMP_ALL_HOSTS) 1558 continue; 1559 if (ipv4_is_local_multicast(im->multiaddr) && 1560 !net->ipv4.sysctl_igmp_llm_reports) 1561 continue; 1562 1563 /* a failover is happening and switches 1564 * must be notified immediately 1565 */ 1566 if (IGMP_V1_SEEN(in_dev)) 1567 type = IGMP_HOST_MEMBERSHIP_REPORT; 1568 else if (IGMP_V2_SEEN(in_dev)) 1569 type = IGMPV2_HOST_MEMBERSHIP_REPORT; 1570 else 1571 type = IGMPV3_HOST_MEMBERSHIP_REPORT; 1572 igmp_send_report(in_dev, im, type); 1573 } 1574 #endif 1575 } 1576 1577 /* 1578 * A socket has left a multicast group on device dev 1579 */ 1580 1581 void ip_mc_dec_group(struct in_device *in_dev, __be32 addr) 1582 { 1583 struct ip_mc_list *i; 1584 struct ip_mc_list __rcu **ip; 1585 1586 ASSERT_RTNL(); 1587 1588 for (ip = &in_dev->mc_list; 1589 (i = rtnl_dereference(*ip)) != NULL; 1590 ip = &i->next_rcu) { 1591 if (i->multiaddr == addr) { 1592 if (--i->users == 0) { 1593 ip_mc_hash_remove(in_dev, i); 1594 *ip = i->next_rcu; 1595 in_dev->mc_count--; 1596 igmp_group_dropped(i); 1597 ip_mc_clear_src(i); 1598 1599 if (!in_dev->dead) 1600 ip_rt_multicast_event(in_dev); 1601 1602 ip_ma_put(i); 1603 return; 1604 } 1605 break; 1606 } 1607 } 1608 } 1609 EXPORT_SYMBOL(ip_mc_dec_group); 1610 1611 /* Device changing type */ 1612 1613 void ip_mc_unmap(struct in_device *in_dev) 1614 { 1615 struct ip_mc_list *pmc; 1616 1617 ASSERT_RTNL(); 1618 1619 for_each_pmc_rtnl(in_dev, pmc) 1620 igmp_group_dropped(pmc); 1621 } 1622 1623 void ip_mc_remap(struct in_device *in_dev) 1624 { 1625 struct ip_mc_list *pmc; 1626 1627 ASSERT_RTNL(); 1628 1629 for_each_pmc_rtnl(in_dev, pmc) 1630 igmp_group_added(pmc); 1631 } 1632 1633 /* Device going down */ 1634 1635 void ip_mc_down(struct in_device *in_dev) 1636 { 1637 struct ip_mc_list *pmc; 1638 1639 ASSERT_RTNL(); 1640 1641 for_each_pmc_rtnl(in_dev, pmc) 1642 igmp_group_dropped(pmc); 1643 1644 #ifdef CONFIG_IP_MULTICAST 1645 in_dev->mr_ifc_count = 0; 1646 if (del_timer(&in_dev->mr_ifc_timer)) 1647 __in_dev_put(in_dev); 1648 in_dev->mr_gq_running = 0; 1649 if (del_timer(&in_dev->mr_gq_timer)) 1650 __in_dev_put(in_dev); 1651 igmpv3_clear_delrec(in_dev); 1652 #endif 1653 1654 ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS); 1655 } 1656 1657 void ip_mc_init_dev(struct in_device *in_dev) 1658 { 1659 #ifdef CONFIG_IP_MULTICAST 1660 struct net *net = dev_net(in_dev->dev); 1661 #endif 1662 ASSERT_RTNL(); 1663 1664 #ifdef CONFIG_IP_MULTICAST 1665 setup_timer(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 1666 (unsigned long)in_dev); 1667 setup_timer(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 1668 (unsigned long)in_dev); 1669 in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv; 1670 #endif 1671 1672 spin_lock_init(&in_dev->mc_tomb_lock); 1673 } 1674 1675 /* Device going up */ 1676 1677 void ip_mc_up(struct in_device *in_dev) 1678 { 1679 struct ip_mc_list *pmc; 1680 #ifdef CONFIG_IP_MULTICAST 1681 struct net *net = dev_net(in_dev->dev); 1682 #endif 1683 1684 ASSERT_RTNL(); 1685 1686 #ifdef CONFIG_IP_MULTICAST 1687 in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv; 1688 #endif 1689 ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS); 1690 1691 for_each_pmc_rtnl(in_dev, pmc) 1692 igmp_group_added(pmc); 1693 } 1694 1695 /* 1696 * Device is about to be destroyed: clean up. 1697 */ 1698 1699 void ip_mc_destroy_dev(struct in_device *in_dev) 1700 { 1701 struct ip_mc_list *i; 1702 1703 ASSERT_RTNL(); 1704 1705 /* Deactivate timers */ 1706 ip_mc_down(in_dev); 1707 1708 while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) { 1709 in_dev->mc_list = i->next_rcu; 1710 in_dev->mc_count--; 1711 1712 /* We've dropped the groups in ip_mc_down already */ 1713 ip_mc_clear_src(i); 1714 ip_ma_put(i); 1715 } 1716 } 1717 1718 /* RTNL is locked */ 1719 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr) 1720 { 1721 struct net_device *dev = NULL; 1722 struct in_device *idev = NULL; 1723 1724 if (imr->imr_ifindex) { 1725 idev = inetdev_by_index(net, imr->imr_ifindex); 1726 return idev; 1727 } 1728 if (imr->imr_address.s_addr) { 1729 dev = __ip_dev_find(net, imr->imr_address.s_addr, false); 1730 if (!dev) 1731 return NULL; 1732 } 1733 1734 if (!dev) { 1735 struct rtable *rt = ip_route_output(net, 1736 imr->imr_multiaddr.s_addr, 1737 0, 0, 0); 1738 if (!IS_ERR(rt)) { 1739 dev = rt->dst.dev; 1740 ip_rt_put(rt); 1741 } 1742 } 1743 if (dev) { 1744 imr->imr_ifindex = dev->ifindex; 1745 idev = __in_dev_get_rtnl(dev); 1746 } 1747 return idev; 1748 } 1749 1750 /* 1751 * Join a socket to a group 1752 */ 1753 1754 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode, 1755 __be32 *psfsrc) 1756 { 1757 struct ip_sf_list *psf, *psf_prev; 1758 int rv = 0; 1759 1760 psf_prev = NULL; 1761 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1762 if (psf->sf_inaddr == *psfsrc) 1763 break; 1764 psf_prev = psf; 1765 } 1766 if (!psf || psf->sf_count[sfmode] == 0) { 1767 /* source filter not found, or count wrong => bug */ 1768 return -ESRCH; 1769 } 1770 psf->sf_count[sfmode]--; 1771 if (psf->sf_count[sfmode] == 0) { 1772 ip_rt_multicast_event(pmc->interface); 1773 } 1774 if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) { 1775 #ifdef CONFIG_IP_MULTICAST 1776 struct in_device *in_dev = pmc->interface; 1777 struct net *net = dev_net(in_dev->dev); 1778 #endif 1779 1780 /* no more filters for this source */ 1781 if (psf_prev) 1782 psf_prev->sf_next = psf->sf_next; 1783 else 1784 pmc->sources = psf->sf_next; 1785 #ifdef CONFIG_IP_MULTICAST 1786 if (psf->sf_oldin && 1787 !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) { 1788 psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1789 psf->sf_next = pmc->tomb; 1790 pmc->tomb = psf; 1791 rv = 1; 1792 } else 1793 #endif 1794 kfree(psf); 1795 } 1796 return rv; 1797 } 1798 1799 #ifndef CONFIG_IP_MULTICAST 1800 #define igmp_ifc_event(x) do { } while (0) 1801 #endif 1802 1803 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 1804 int sfcount, __be32 *psfsrc, int delta) 1805 { 1806 struct ip_mc_list *pmc; 1807 int changerec = 0; 1808 int i, err; 1809 1810 if (!in_dev) 1811 return -ENODEV; 1812 rcu_read_lock(); 1813 for_each_pmc_rcu(in_dev, pmc) { 1814 if (*pmca == pmc->multiaddr) 1815 break; 1816 } 1817 if (!pmc) { 1818 /* MCA not found?? bug */ 1819 rcu_read_unlock(); 1820 return -ESRCH; 1821 } 1822 spin_lock_bh(&pmc->lock); 1823 rcu_read_unlock(); 1824 #ifdef CONFIG_IP_MULTICAST 1825 sf_markstate(pmc); 1826 #endif 1827 if (!delta) { 1828 err = -EINVAL; 1829 if (!pmc->sfcount[sfmode]) 1830 goto out_unlock; 1831 pmc->sfcount[sfmode]--; 1832 } 1833 err = 0; 1834 for (i = 0; i < sfcount; i++) { 1835 int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]); 1836 1837 changerec |= rv > 0; 1838 if (!err && rv < 0) 1839 err = rv; 1840 } 1841 if (pmc->sfmode == MCAST_EXCLUDE && 1842 pmc->sfcount[MCAST_EXCLUDE] == 0 && 1843 pmc->sfcount[MCAST_INCLUDE]) { 1844 #ifdef CONFIG_IP_MULTICAST 1845 struct ip_sf_list *psf; 1846 struct net *net = dev_net(in_dev->dev); 1847 #endif 1848 1849 /* filter mode change */ 1850 pmc->sfmode = MCAST_INCLUDE; 1851 #ifdef CONFIG_IP_MULTICAST 1852 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1853 in_dev->mr_ifc_count = pmc->crcount; 1854 for (psf = pmc->sources; psf; psf = psf->sf_next) 1855 psf->sf_crcount = 0; 1856 igmp_ifc_event(pmc->interface); 1857 } else if (sf_setstate(pmc) || changerec) { 1858 igmp_ifc_event(pmc->interface); 1859 #endif 1860 } 1861 out_unlock: 1862 spin_unlock_bh(&pmc->lock); 1863 return err; 1864 } 1865 1866 /* 1867 * Add multicast single-source filter to the interface list 1868 */ 1869 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode, 1870 __be32 *psfsrc) 1871 { 1872 struct ip_sf_list *psf, *psf_prev; 1873 1874 psf_prev = NULL; 1875 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1876 if (psf->sf_inaddr == *psfsrc) 1877 break; 1878 psf_prev = psf; 1879 } 1880 if (!psf) { 1881 psf = kzalloc(sizeof(*psf), GFP_ATOMIC); 1882 if (!psf) 1883 return -ENOBUFS; 1884 psf->sf_inaddr = *psfsrc; 1885 if (psf_prev) { 1886 psf_prev->sf_next = psf; 1887 } else 1888 pmc->sources = psf; 1889 } 1890 psf->sf_count[sfmode]++; 1891 if (psf->sf_count[sfmode] == 1) { 1892 ip_rt_multicast_event(pmc->interface); 1893 } 1894 return 0; 1895 } 1896 1897 #ifdef CONFIG_IP_MULTICAST 1898 static void sf_markstate(struct ip_mc_list *pmc) 1899 { 1900 struct ip_sf_list *psf; 1901 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; 1902 1903 for (psf = pmc->sources; psf; psf = psf->sf_next) 1904 if (pmc->sfcount[MCAST_EXCLUDE]) { 1905 psf->sf_oldin = mca_xcount == 1906 psf->sf_count[MCAST_EXCLUDE] && 1907 !psf->sf_count[MCAST_INCLUDE]; 1908 } else 1909 psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0; 1910 } 1911 1912 static int sf_setstate(struct ip_mc_list *pmc) 1913 { 1914 struct ip_sf_list *psf, *dpsf; 1915 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; 1916 int qrv = pmc->interface->mr_qrv; 1917 int new_in, rv; 1918 1919 rv = 0; 1920 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1921 if (pmc->sfcount[MCAST_EXCLUDE]) { 1922 new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] && 1923 !psf->sf_count[MCAST_INCLUDE]; 1924 } else 1925 new_in = psf->sf_count[MCAST_INCLUDE] != 0; 1926 if (new_in) { 1927 if (!psf->sf_oldin) { 1928 struct ip_sf_list *prev = NULL; 1929 1930 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) { 1931 if (dpsf->sf_inaddr == psf->sf_inaddr) 1932 break; 1933 prev = dpsf; 1934 } 1935 if (dpsf) { 1936 if (prev) 1937 prev->sf_next = dpsf->sf_next; 1938 else 1939 pmc->tomb = dpsf->sf_next; 1940 kfree(dpsf); 1941 } 1942 psf->sf_crcount = qrv; 1943 rv++; 1944 } 1945 } else if (psf->sf_oldin) { 1946 1947 psf->sf_crcount = 0; 1948 /* 1949 * add or update "delete" records if an active filter 1950 * is now inactive 1951 */ 1952 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) 1953 if (dpsf->sf_inaddr == psf->sf_inaddr) 1954 break; 1955 if (!dpsf) { 1956 dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC); 1957 if (!dpsf) 1958 continue; 1959 *dpsf = *psf; 1960 /* pmc->lock held by callers */ 1961 dpsf->sf_next = pmc->tomb; 1962 pmc->tomb = dpsf; 1963 } 1964 dpsf->sf_crcount = qrv; 1965 rv++; 1966 } 1967 } 1968 return rv; 1969 } 1970 #endif 1971 1972 /* 1973 * Add multicast source filter list to the interface list 1974 */ 1975 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 1976 int sfcount, __be32 *psfsrc, int delta) 1977 { 1978 struct ip_mc_list *pmc; 1979 int isexclude; 1980 int i, err; 1981 1982 if (!in_dev) 1983 return -ENODEV; 1984 rcu_read_lock(); 1985 for_each_pmc_rcu(in_dev, pmc) { 1986 if (*pmca == pmc->multiaddr) 1987 break; 1988 } 1989 if (!pmc) { 1990 /* MCA not found?? bug */ 1991 rcu_read_unlock(); 1992 return -ESRCH; 1993 } 1994 spin_lock_bh(&pmc->lock); 1995 rcu_read_unlock(); 1996 1997 #ifdef CONFIG_IP_MULTICAST 1998 sf_markstate(pmc); 1999 #endif 2000 isexclude = pmc->sfmode == MCAST_EXCLUDE; 2001 if (!delta) 2002 pmc->sfcount[sfmode]++; 2003 err = 0; 2004 for (i = 0; i < sfcount; i++) { 2005 err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]); 2006 if (err) 2007 break; 2008 } 2009 if (err) { 2010 int j; 2011 2012 if (!delta) 2013 pmc->sfcount[sfmode]--; 2014 for (j = 0; j < i; j++) 2015 (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]); 2016 } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) { 2017 #ifdef CONFIG_IP_MULTICAST 2018 struct ip_sf_list *psf; 2019 struct net *net = dev_net(pmc->interface->dev); 2020 in_dev = pmc->interface; 2021 #endif 2022 2023 /* filter mode change */ 2024 if (pmc->sfcount[MCAST_EXCLUDE]) 2025 pmc->sfmode = MCAST_EXCLUDE; 2026 else if (pmc->sfcount[MCAST_INCLUDE]) 2027 pmc->sfmode = MCAST_INCLUDE; 2028 #ifdef CONFIG_IP_MULTICAST 2029 /* else no filters; keep old mode for reports */ 2030 2031 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 2032 in_dev->mr_ifc_count = pmc->crcount; 2033 for (psf = pmc->sources; psf; psf = psf->sf_next) 2034 psf->sf_crcount = 0; 2035 igmp_ifc_event(in_dev); 2036 } else if (sf_setstate(pmc)) { 2037 igmp_ifc_event(in_dev); 2038 #endif 2039 } 2040 spin_unlock_bh(&pmc->lock); 2041 return err; 2042 } 2043 2044 static void ip_mc_clear_src(struct ip_mc_list *pmc) 2045 { 2046 struct ip_sf_list *psf, *nextpsf; 2047 2048 for (psf = pmc->tomb; psf; psf = nextpsf) { 2049 nextpsf = psf->sf_next; 2050 kfree(psf); 2051 } 2052 pmc->tomb = NULL; 2053 for (psf = pmc->sources; psf; psf = nextpsf) { 2054 nextpsf = psf->sf_next; 2055 kfree(psf); 2056 } 2057 pmc->sources = NULL; 2058 pmc->sfmode = MCAST_EXCLUDE; 2059 pmc->sfcount[MCAST_INCLUDE] = 0; 2060 pmc->sfcount[MCAST_EXCLUDE] = 1; 2061 } 2062 2063 /* Join a multicast group 2064 */ 2065 2066 int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr) 2067 { 2068 __be32 addr = imr->imr_multiaddr.s_addr; 2069 struct ip_mc_socklist *iml, *i; 2070 struct in_device *in_dev; 2071 struct inet_sock *inet = inet_sk(sk); 2072 struct net *net = sock_net(sk); 2073 int ifindex; 2074 int count = 0; 2075 int err; 2076 2077 ASSERT_RTNL(); 2078 2079 if (!ipv4_is_multicast(addr)) 2080 return -EINVAL; 2081 2082 in_dev = ip_mc_find_dev(net, imr); 2083 2084 if (!in_dev) { 2085 err = -ENODEV; 2086 goto done; 2087 } 2088 2089 err = -EADDRINUSE; 2090 ifindex = imr->imr_ifindex; 2091 for_each_pmc_rtnl(inet, i) { 2092 if (i->multi.imr_multiaddr.s_addr == addr && 2093 i->multi.imr_ifindex == ifindex) 2094 goto done; 2095 count++; 2096 } 2097 err = -ENOBUFS; 2098 if (count >= net->ipv4.sysctl_igmp_max_memberships) 2099 goto done; 2100 iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL); 2101 if (!iml) 2102 goto done; 2103 2104 memcpy(&iml->multi, imr, sizeof(*imr)); 2105 iml->next_rcu = inet->mc_list; 2106 iml->sflist = NULL; 2107 iml->sfmode = MCAST_EXCLUDE; 2108 rcu_assign_pointer(inet->mc_list, iml); 2109 ip_mc_inc_group(in_dev, addr); 2110 err = 0; 2111 done: 2112 return err; 2113 } 2114 EXPORT_SYMBOL(ip_mc_join_group); 2115 2116 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml, 2117 struct in_device *in_dev) 2118 { 2119 struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist); 2120 int err; 2121 2122 if (!psf) { 2123 /* any-source empty exclude case */ 2124 return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, 2125 iml->sfmode, 0, NULL, 0); 2126 } 2127 err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, 2128 iml->sfmode, psf->sl_count, psf->sl_addr, 0); 2129 RCU_INIT_POINTER(iml->sflist, NULL); 2130 /* decrease mem now to avoid the memleak warning */ 2131 atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc); 2132 kfree_rcu(psf, rcu); 2133 return err; 2134 } 2135 2136 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr) 2137 { 2138 struct inet_sock *inet = inet_sk(sk); 2139 struct ip_mc_socklist *iml; 2140 struct ip_mc_socklist __rcu **imlp; 2141 struct in_device *in_dev; 2142 struct net *net = sock_net(sk); 2143 __be32 group = imr->imr_multiaddr.s_addr; 2144 u32 ifindex; 2145 int ret = -EADDRNOTAVAIL; 2146 2147 ASSERT_RTNL(); 2148 2149 in_dev = ip_mc_find_dev(net, imr); 2150 if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) { 2151 ret = -ENODEV; 2152 goto out; 2153 } 2154 ifindex = imr->imr_ifindex; 2155 for (imlp = &inet->mc_list; 2156 (iml = rtnl_dereference(*imlp)) != NULL; 2157 imlp = &iml->next_rcu) { 2158 if (iml->multi.imr_multiaddr.s_addr != group) 2159 continue; 2160 if (ifindex) { 2161 if (iml->multi.imr_ifindex != ifindex) 2162 continue; 2163 } else if (imr->imr_address.s_addr && imr->imr_address.s_addr != 2164 iml->multi.imr_address.s_addr) 2165 continue; 2166 2167 (void) ip_mc_leave_src(sk, iml, in_dev); 2168 2169 *imlp = iml->next_rcu; 2170 2171 if (in_dev) 2172 ip_mc_dec_group(in_dev, group); 2173 2174 /* decrease mem now to avoid the memleak warning */ 2175 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); 2176 kfree_rcu(iml, rcu); 2177 return 0; 2178 } 2179 out: 2180 return ret; 2181 } 2182 EXPORT_SYMBOL(ip_mc_leave_group); 2183 2184 int ip_mc_source(int add, int omode, struct sock *sk, struct 2185 ip_mreq_source *mreqs, int ifindex) 2186 { 2187 int err; 2188 struct ip_mreqn imr; 2189 __be32 addr = mreqs->imr_multiaddr; 2190 struct ip_mc_socklist *pmc; 2191 struct in_device *in_dev = NULL; 2192 struct inet_sock *inet = inet_sk(sk); 2193 struct ip_sf_socklist *psl; 2194 struct net *net = sock_net(sk); 2195 int leavegroup = 0; 2196 int i, j, rv; 2197 2198 if (!ipv4_is_multicast(addr)) 2199 return -EINVAL; 2200 2201 ASSERT_RTNL(); 2202 2203 imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr; 2204 imr.imr_address.s_addr = mreqs->imr_interface; 2205 imr.imr_ifindex = ifindex; 2206 in_dev = ip_mc_find_dev(net, &imr); 2207 2208 if (!in_dev) { 2209 err = -ENODEV; 2210 goto done; 2211 } 2212 err = -EADDRNOTAVAIL; 2213 2214 for_each_pmc_rtnl(inet, pmc) { 2215 if ((pmc->multi.imr_multiaddr.s_addr == 2216 imr.imr_multiaddr.s_addr) && 2217 (pmc->multi.imr_ifindex == imr.imr_ifindex)) 2218 break; 2219 } 2220 if (!pmc) { /* must have a prior join */ 2221 err = -EINVAL; 2222 goto done; 2223 } 2224 /* if a source filter was set, must be the same mode as before */ 2225 if (pmc->sflist) { 2226 if (pmc->sfmode != omode) { 2227 err = -EINVAL; 2228 goto done; 2229 } 2230 } else if (pmc->sfmode != omode) { 2231 /* allow mode switches for empty-set filters */ 2232 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0); 2233 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0, 2234 NULL, 0); 2235 pmc->sfmode = omode; 2236 } 2237 2238 psl = rtnl_dereference(pmc->sflist); 2239 if (!add) { 2240 if (!psl) 2241 goto done; /* err = -EADDRNOTAVAIL */ 2242 rv = !0; 2243 for (i = 0; i < psl->sl_count; i++) { 2244 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr, 2245 sizeof(__be32)); 2246 if (rv == 0) 2247 break; 2248 } 2249 if (rv) /* source not found */ 2250 goto done; /* err = -EADDRNOTAVAIL */ 2251 2252 /* special case - (INCLUDE, empty) == LEAVE_GROUP */ 2253 if (psl->sl_count == 1 && omode == MCAST_INCLUDE) { 2254 leavegroup = 1; 2255 goto done; 2256 } 2257 2258 /* update the interface filter */ 2259 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1, 2260 &mreqs->imr_sourceaddr, 1); 2261 2262 for (j = i+1; j < psl->sl_count; j++) 2263 psl->sl_addr[j-1] = psl->sl_addr[j]; 2264 psl->sl_count--; 2265 err = 0; 2266 goto done; 2267 } 2268 /* else, add a new source to the filter */ 2269 2270 if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) { 2271 err = -ENOBUFS; 2272 goto done; 2273 } 2274 if (!psl || psl->sl_count == psl->sl_max) { 2275 struct ip_sf_socklist *newpsl; 2276 int count = IP_SFBLOCK; 2277 2278 if (psl) 2279 count += psl->sl_max; 2280 newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL); 2281 if (!newpsl) { 2282 err = -ENOBUFS; 2283 goto done; 2284 } 2285 newpsl->sl_max = count; 2286 newpsl->sl_count = count - IP_SFBLOCK; 2287 if (psl) { 2288 for (i = 0; i < psl->sl_count; i++) 2289 newpsl->sl_addr[i] = psl->sl_addr[i]; 2290 /* decrease mem now to avoid the memleak warning */ 2291 atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc); 2292 kfree_rcu(psl, rcu); 2293 } 2294 rcu_assign_pointer(pmc->sflist, newpsl); 2295 psl = newpsl; 2296 } 2297 rv = 1; /* > 0 for insert logic below if sl_count is 0 */ 2298 for (i = 0; i < psl->sl_count; i++) { 2299 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr, 2300 sizeof(__be32)); 2301 if (rv == 0) 2302 break; 2303 } 2304 if (rv == 0) /* address already there is an error */ 2305 goto done; 2306 for (j = psl->sl_count-1; j >= i; j--) 2307 psl->sl_addr[j+1] = psl->sl_addr[j]; 2308 psl->sl_addr[i] = mreqs->imr_sourceaddr; 2309 psl->sl_count++; 2310 err = 0; 2311 /* update the interface list */ 2312 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1, 2313 &mreqs->imr_sourceaddr, 1); 2314 done: 2315 if (leavegroup) 2316 err = ip_mc_leave_group(sk, &imr); 2317 return err; 2318 } 2319 2320 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex) 2321 { 2322 int err = 0; 2323 struct ip_mreqn imr; 2324 __be32 addr = msf->imsf_multiaddr; 2325 struct ip_mc_socklist *pmc; 2326 struct in_device *in_dev; 2327 struct inet_sock *inet = inet_sk(sk); 2328 struct ip_sf_socklist *newpsl, *psl; 2329 struct net *net = sock_net(sk); 2330 int leavegroup = 0; 2331 2332 if (!ipv4_is_multicast(addr)) 2333 return -EINVAL; 2334 if (msf->imsf_fmode != MCAST_INCLUDE && 2335 msf->imsf_fmode != MCAST_EXCLUDE) 2336 return -EINVAL; 2337 2338 ASSERT_RTNL(); 2339 2340 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; 2341 imr.imr_address.s_addr = msf->imsf_interface; 2342 imr.imr_ifindex = ifindex; 2343 in_dev = ip_mc_find_dev(net, &imr); 2344 2345 if (!in_dev) { 2346 err = -ENODEV; 2347 goto done; 2348 } 2349 2350 /* special case - (INCLUDE, empty) == LEAVE_GROUP */ 2351 if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) { 2352 leavegroup = 1; 2353 goto done; 2354 } 2355 2356 for_each_pmc_rtnl(inet, pmc) { 2357 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && 2358 pmc->multi.imr_ifindex == imr.imr_ifindex) 2359 break; 2360 } 2361 if (!pmc) { /* must have a prior join */ 2362 err = -EINVAL; 2363 goto done; 2364 } 2365 if (msf->imsf_numsrc) { 2366 newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc), 2367 GFP_KERNEL); 2368 if (!newpsl) { 2369 err = -ENOBUFS; 2370 goto done; 2371 } 2372 newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc; 2373 memcpy(newpsl->sl_addr, msf->imsf_slist, 2374 msf->imsf_numsrc * sizeof(msf->imsf_slist[0])); 2375 err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr, 2376 msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0); 2377 if (err) { 2378 sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max)); 2379 goto done; 2380 } 2381 } else { 2382 newpsl = NULL; 2383 (void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr, 2384 msf->imsf_fmode, 0, NULL, 0); 2385 } 2386 psl = rtnl_dereference(pmc->sflist); 2387 if (psl) { 2388 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, 2389 psl->sl_count, psl->sl_addr, 0); 2390 /* decrease mem now to avoid the memleak warning */ 2391 atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc); 2392 kfree_rcu(psl, rcu); 2393 } else 2394 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, 2395 0, NULL, 0); 2396 rcu_assign_pointer(pmc->sflist, newpsl); 2397 pmc->sfmode = msf->imsf_fmode; 2398 err = 0; 2399 done: 2400 if (leavegroup) 2401 err = ip_mc_leave_group(sk, &imr); 2402 return err; 2403 } 2404 2405 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf, 2406 struct ip_msfilter __user *optval, int __user *optlen) 2407 { 2408 int err, len, count, copycount; 2409 struct ip_mreqn imr; 2410 __be32 addr = msf->imsf_multiaddr; 2411 struct ip_mc_socklist *pmc; 2412 struct in_device *in_dev; 2413 struct inet_sock *inet = inet_sk(sk); 2414 struct ip_sf_socklist *psl; 2415 struct net *net = sock_net(sk); 2416 2417 ASSERT_RTNL(); 2418 2419 if (!ipv4_is_multicast(addr)) 2420 return -EINVAL; 2421 2422 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; 2423 imr.imr_address.s_addr = msf->imsf_interface; 2424 imr.imr_ifindex = 0; 2425 in_dev = ip_mc_find_dev(net, &imr); 2426 2427 if (!in_dev) { 2428 err = -ENODEV; 2429 goto done; 2430 } 2431 err = -EADDRNOTAVAIL; 2432 2433 for_each_pmc_rtnl(inet, pmc) { 2434 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && 2435 pmc->multi.imr_ifindex == imr.imr_ifindex) 2436 break; 2437 } 2438 if (!pmc) /* must have a prior join */ 2439 goto done; 2440 msf->imsf_fmode = pmc->sfmode; 2441 psl = rtnl_dereference(pmc->sflist); 2442 if (!psl) { 2443 len = 0; 2444 count = 0; 2445 } else { 2446 count = psl->sl_count; 2447 } 2448 copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc; 2449 len = copycount * sizeof(psl->sl_addr[0]); 2450 msf->imsf_numsrc = count; 2451 if (put_user(IP_MSFILTER_SIZE(copycount), optlen) || 2452 copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) { 2453 return -EFAULT; 2454 } 2455 if (len && 2456 copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len)) 2457 return -EFAULT; 2458 return 0; 2459 done: 2460 return err; 2461 } 2462 2463 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf, 2464 struct group_filter __user *optval, int __user *optlen) 2465 { 2466 int err, i, count, copycount; 2467 struct sockaddr_in *psin; 2468 __be32 addr; 2469 struct ip_mc_socklist *pmc; 2470 struct inet_sock *inet = inet_sk(sk); 2471 struct ip_sf_socklist *psl; 2472 2473 ASSERT_RTNL(); 2474 2475 psin = (struct sockaddr_in *)&gsf->gf_group; 2476 if (psin->sin_family != AF_INET) 2477 return -EINVAL; 2478 addr = psin->sin_addr.s_addr; 2479 if (!ipv4_is_multicast(addr)) 2480 return -EINVAL; 2481 2482 err = -EADDRNOTAVAIL; 2483 2484 for_each_pmc_rtnl(inet, pmc) { 2485 if (pmc->multi.imr_multiaddr.s_addr == addr && 2486 pmc->multi.imr_ifindex == gsf->gf_interface) 2487 break; 2488 } 2489 if (!pmc) /* must have a prior join */ 2490 goto done; 2491 gsf->gf_fmode = pmc->sfmode; 2492 psl = rtnl_dereference(pmc->sflist); 2493 count = psl ? psl->sl_count : 0; 2494 copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc; 2495 gsf->gf_numsrc = count; 2496 if (put_user(GROUP_FILTER_SIZE(copycount), optlen) || 2497 copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) { 2498 return -EFAULT; 2499 } 2500 for (i = 0; i < copycount; i++) { 2501 struct sockaddr_storage ss; 2502 2503 psin = (struct sockaddr_in *)&ss; 2504 memset(&ss, 0, sizeof(ss)); 2505 psin->sin_family = AF_INET; 2506 psin->sin_addr.s_addr = psl->sl_addr[i]; 2507 if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss))) 2508 return -EFAULT; 2509 } 2510 return 0; 2511 done: 2512 return err; 2513 } 2514 2515 /* 2516 * check if a multicast source filter allows delivery for a given <src,dst,intf> 2517 */ 2518 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif) 2519 { 2520 struct inet_sock *inet = inet_sk(sk); 2521 struct ip_mc_socklist *pmc; 2522 struct ip_sf_socklist *psl; 2523 int i; 2524 int ret; 2525 2526 ret = 1; 2527 if (!ipv4_is_multicast(loc_addr)) 2528 goto out; 2529 2530 rcu_read_lock(); 2531 for_each_pmc_rcu(inet, pmc) { 2532 if (pmc->multi.imr_multiaddr.s_addr == loc_addr && 2533 pmc->multi.imr_ifindex == dif) 2534 break; 2535 } 2536 ret = inet->mc_all; 2537 if (!pmc) 2538 goto unlock; 2539 psl = rcu_dereference(pmc->sflist); 2540 ret = (pmc->sfmode == MCAST_EXCLUDE); 2541 if (!psl) 2542 goto unlock; 2543 2544 for (i = 0; i < psl->sl_count; i++) { 2545 if (psl->sl_addr[i] == rmt_addr) 2546 break; 2547 } 2548 ret = 0; 2549 if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count) 2550 goto unlock; 2551 if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count) 2552 goto unlock; 2553 ret = 1; 2554 unlock: 2555 rcu_read_unlock(); 2556 out: 2557 return ret; 2558 } 2559 2560 /* 2561 * A socket is closing. 2562 */ 2563 2564 void ip_mc_drop_socket(struct sock *sk) 2565 { 2566 struct inet_sock *inet = inet_sk(sk); 2567 struct ip_mc_socklist *iml; 2568 struct net *net = sock_net(sk); 2569 2570 if (!inet->mc_list) 2571 return; 2572 2573 rtnl_lock(); 2574 while ((iml = rtnl_dereference(inet->mc_list)) != NULL) { 2575 struct in_device *in_dev; 2576 2577 inet->mc_list = iml->next_rcu; 2578 in_dev = inetdev_by_index(net, iml->multi.imr_ifindex); 2579 (void) ip_mc_leave_src(sk, iml, in_dev); 2580 if (in_dev) 2581 ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr); 2582 /* decrease mem now to avoid the memleak warning */ 2583 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); 2584 kfree_rcu(iml, rcu); 2585 } 2586 rtnl_unlock(); 2587 } 2588 2589 /* called with rcu_read_lock() */ 2590 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto) 2591 { 2592 struct ip_mc_list *im; 2593 struct ip_mc_list __rcu **mc_hash; 2594 struct ip_sf_list *psf; 2595 int rv = 0; 2596 2597 mc_hash = rcu_dereference(in_dev->mc_hash); 2598 if (mc_hash) { 2599 u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG); 2600 2601 for (im = rcu_dereference(mc_hash[hash]); 2602 im != NULL; 2603 im = rcu_dereference(im->next_hash)) { 2604 if (im->multiaddr == mc_addr) 2605 break; 2606 } 2607 } else { 2608 for_each_pmc_rcu(in_dev, im) { 2609 if (im->multiaddr == mc_addr) 2610 break; 2611 } 2612 } 2613 if (im && proto == IPPROTO_IGMP) { 2614 rv = 1; 2615 } else if (im) { 2616 if (src_addr) { 2617 for (psf = im->sources; psf; psf = psf->sf_next) { 2618 if (psf->sf_inaddr == src_addr) 2619 break; 2620 } 2621 if (psf) 2622 rv = psf->sf_count[MCAST_INCLUDE] || 2623 psf->sf_count[MCAST_EXCLUDE] != 2624 im->sfcount[MCAST_EXCLUDE]; 2625 else 2626 rv = im->sfcount[MCAST_EXCLUDE] != 0; 2627 } else 2628 rv = 1; /* unspecified source; tentatively allow */ 2629 } 2630 return rv; 2631 } 2632 2633 #if defined(CONFIG_PROC_FS) 2634 struct igmp_mc_iter_state { 2635 struct seq_net_private p; 2636 struct net_device *dev; 2637 struct in_device *in_dev; 2638 }; 2639 2640 #define igmp_mc_seq_private(seq) ((struct igmp_mc_iter_state *)(seq)->private) 2641 2642 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq) 2643 { 2644 struct net *net = seq_file_net(seq); 2645 struct ip_mc_list *im = NULL; 2646 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2647 2648 state->in_dev = NULL; 2649 for_each_netdev_rcu(net, state->dev) { 2650 struct in_device *in_dev; 2651 2652 in_dev = __in_dev_get_rcu(state->dev); 2653 if (!in_dev) 2654 continue; 2655 im = rcu_dereference(in_dev->mc_list); 2656 if (im) { 2657 state->in_dev = in_dev; 2658 break; 2659 } 2660 } 2661 return im; 2662 } 2663 2664 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im) 2665 { 2666 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2667 2668 im = rcu_dereference(im->next_rcu); 2669 while (!im) { 2670 state->dev = next_net_device_rcu(state->dev); 2671 if (!state->dev) { 2672 state->in_dev = NULL; 2673 break; 2674 } 2675 state->in_dev = __in_dev_get_rcu(state->dev); 2676 if (!state->in_dev) 2677 continue; 2678 im = rcu_dereference(state->in_dev->mc_list); 2679 } 2680 return im; 2681 } 2682 2683 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos) 2684 { 2685 struct ip_mc_list *im = igmp_mc_get_first(seq); 2686 if (im) 2687 while (pos && (im = igmp_mc_get_next(seq, im)) != NULL) 2688 --pos; 2689 return pos ? NULL : im; 2690 } 2691 2692 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos) 2693 __acquires(rcu) 2694 { 2695 rcu_read_lock(); 2696 return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 2697 } 2698 2699 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2700 { 2701 struct ip_mc_list *im; 2702 if (v == SEQ_START_TOKEN) 2703 im = igmp_mc_get_first(seq); 2704 else 2705 im = igmp_mc_get_next(seq, v); 2706 ++*pos; 2707 return im; 2708 } 2709 2710 static void igmp_mc_seq_stop(struct seq_file *seq, void *v) 2711 __releases(rcu) 2712 { 2713 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2714 2715 state->in_dev = NULL; 2716 state->dev = NULL; 2717 rcu_read_unlock(); 2718 } 2719 2720 static int igmp_mc_seq_show(struct seq_file *seq, void *v) 2721 { 2722 if (v == SEQ_START_TOKEN) 2723 seq_puts(seq, 2724 "Idx\tDevice : Count Querier\tGroup Users Timer\tReporter\n"); 2725 else { 2726 struct ip_mc_list *im = (struct ip_mc_list *)v; 2727 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2728 char *querier; 2729 long delta; 2730 2731 #ifdef CONFIG_IP_MULTICAST 2732 querier = IGMP_V1_SEEN(state->in_dev) ? "V1" : 2733 IGMP_V2_SEEN(state->in_dev) ? "V2" : 2734 "V3"; 2735 #else 2736 querier = "NONE"; 2737 #endif 2738 2739 if (rcu_access_pointer(state->in_dev->mc_list) == im) { 2740 seq_printf(seq, "%d\t%-10s: %5d %7s\n", 2741 state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier); 2742 } 2743 2744 delta = im->timer.expires - jiffies; 2745 seq_printf(seq, 2746 "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n", 2747 im->multiaddr, im->users, 2748 im->tm_running, 2749 im->tm_running ? jiffies_delta_to_clock_t(delta) : 0, 2750 im->reporter); 2751 } 2752 return 0; 2753 } 2754 2755 static const struct seq_operations igmp_mc_seq_ops = { 2756 .start = igmp_mc_seq_start, 2757 .next = igmp_mc_seq_next, 2758 .stop = igmp_mc_seq_stop, 2759 .show = igmp_mc_seq_show, 2760 }; 2761 2762 static int igmp_mc_seq_open(struct inode *inode, struct file *file) 2763 { 2764 return seq_open_net(inode, file, &igmp_mc_seq_ops, 2765 sizeof(struct igmp_mc_iter_state)); 2766 } 2767 2768 static const struct file_operations igmp_mc_seq_fops = { 2769 .owner = THIS_MODULE, 2770 .open = igmp_mc_seq_open, 2771 .read = seq_read, 2772 .llseek = seq_lseek, 2773 .release = seq_release_net, 2774 }; 2775 2776 struct igmp_mcf_iter_state { 2777 struct seq_net_private p; 2778 struct net_device *dev; 2779 struct in_device *idev; 2780 struct ip_mc_list *im; 2781 }; 2782 2783 #define igmp_mcf_seq_private(seq) ((struct igmp_mcf_iter_state *)(seq)->private) 2784 2785 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq) 2786 { 2787 struct net *net = seq_file_net(seq); 2788 struct ip_sf_list *psf = NULL; 2789 struct ip_mc_list *im = NULL; 2790 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2791 2792 state->idev = NULL; 2793 state->im = NULL; 2794 for_each_netdev_rcu(net, state->dev) { 2795 struct in_device *idev; 2796 idev = __in_dev_get_rcu(state->dev); 2797 if (unlikely(!idev)) 2798 continue; 2799 im = rcu_dereference(idev->mc_list); 2800 if (likely(im)) { 2801 spin_lock_bh(&im->lock); 2802 psf = im->sources; 2803 if (likely(psf)) { 2804 state->im = im; 2805 state->idev = idev; 2806 break; 2807 } 2808 spin_unlock_bh(&im->lock); 2809 } 2810 } 2811 return psf; 2812 } 2813 2814 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf) 2815 { 2816 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2817 2818 psf = psf->sf_next; 2819 while (!psf) { 2820 spin_unlock_bh(&state->im->lock); 2821 state->im = state->im->next; 2822 while (!state->im) { 2823 state->dev = next_net_device_rcu(state->dev); 2824 if (!state->dev) { 2825 state->idev = NULL; 2826 goto out; 2827 } 2828 state->idev = __in_dev_get_rcu(state->dev); 2829 if (!state->idev) 2830 continue; 2831 state->im = rcu_dereference(state->idev->mc_list); 2832 } 2833 if (!state->im) 2834 break; 2835 spin_lock_bh(&state->im->lock); 2836 psf = state->im->sources; 2837 } 2838 out: 2839 return psf; 2840 } 2841 2842 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos) 2843 { 2844 struct ip_sf_list *psf = igmp_mcf_get_first(seq); 2845 if (psf) 2846 while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL) 2847 --pos; 2848 return pos ? NULL : psf; 2849 } 2850 2851 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos) 2852 __acquires(rcu) 2853 { 2854 rcu_read_lock(); 2855 return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 2856 } 2857 2858 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2859 { 2860 struct ip_sf_list *psf; 2861 if (v == SEQ_START_TOKEN) 2862 psf = igmp_mcf_get_first(seq); 2863 else 2864 psf = igmp_mcf_get_next(seq, v); 2865 ++*pos; 2866 return psf; 2867 } 2868 2869 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v) 2870 __releases(rcu) 2871 { 2872 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2873 if (likely(state->im)) { 2874 spin_unlock_bh(&state->im->lock); 2875 state->im = NULL; 2876 } 2877 state->idev = NULL; 2878 state->dev = NULL; 2879 rcu_read_unlock(); 2880 } 2881 2882 static int igmp_mcf_seq_show(struct seq_file *seq, void *v) 2883 { 2884 struct ip_sf_list *psf = (struct ip_sf_list *)v; 2885 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2886 2887 if (v == SEQ_START_TOKEN) { 2888 seq_puts(seq, "Idx Device MCA SRC INC EXC\n"); 2889 } else { 2890 seq_printf(seq, 2891 "%3d %6.6s 0x%08x " 2892 "0x%08x %6lu %6lu\n", 2893 state->dev->ifindex, state->dev->name, 2894 ntohl(state->im->multiaddr), 2895 ntohl(psf->sf_inaddr), 2896 psf->sf_count[MCAST_INCLUDE], 2897 psf->sf_count[MCAST_EXCLUDE]); 2898 } 2899 return 0; 2900 } 2901 2902 static const struct seq_operations igmp_mcf_seq_ops = { 2903 .start = igmp_mcf_seq_start, 2904 .next = igmp_mcf_seq_next, 2905 .stop = igmp_mcf_seq_stop, 2906 .show = igmp_mcf_seq_show, 2907 }; 2908 2909 static int igmp_mcf_seq_open(struct inode *inode, struct file *file) 2910 { 2911 return seq_open_net(inode, file, &igmp_mcf_seq_ops, 2912 sizeof(struct igmp_mcf_iter_state)); 2913 } 2914 2915 static const struct file_operations igmp_mcf_seq_fops = { 2916 .owner = THIS_MODULE, 2917 .open = igmp_mcf_seq_open, 2918 .read = seq_read, 2919 .llseek = seq_lseek, 2920 .release = seq_release_net, 2921 }; 2922 2923 static int __net_init igmp_net_init(struct net *net) 2924 { 2925 struct proc_dir_entry *pde; 2926 int err; 2927 2928 pde = proc_create("igmp", S_IRUGO, net->proc_net, &igmp_mc_seq_fops); 2929 if (!pde) 2930 goto out_igmp; 2931 pde = proc_create("mcfilter", S_IRUGO, net->proc_net, 2932 &igmp_mcf_seq_fops); 2933 if (!pde) 2934 goto out_mcfilter; 2935 err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET, 2936 SOCK_DGRAM, 0, net); 2937 if (err < 0) { 2938 pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n", 2939 err); 2940 goto out_sock; 2941 } 2942 2943 /* Sysctl initialization */ 2944 net->ipv4.sysctl_igmp_max_memberships = 20; 2945 net->ipv4.sysctl_igmp_max_msf = 10; 2946 /* IGMP reports for link-local multicast groups are enabled by default */ 2947 net->ipv4.sysctl_igmp_llm_reports = 1; 2948 net->ipv4.sysctl_igmp_qrv = 2; 2949 return 0; 2950 2951 out_sock: 2952 remove_proc_entry("mcfilter", net->proc_net); 2953 out_mcfilter: 2954 remove_proc_entry("igmp", net->proc_net); 2955 out_igmp: 2956 return -ENOMEM; 2957 } 2958 2959 static void __net_exit igmp_net_exit(struct net *net) 2960 { 2961 remove_proc_entry("mcfilter", net->proc_net); 2962 remove_proc_entry("igmp", net->proc_net); 2963 inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk); 2964 } 2965 2966 static struct pernet_operations igmp_net_ops = { 2967 .init = igmp_net_init, 2968 .exit = igmp_net_exit, 2969 }; 2970 #endif 2971 2972 static int igmp_netdev_event(struct notifier_block *this, 2973 unsigned long event, void *ptr) 2974 { 2975 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 2976 struct in_device *in_dev; 2977 2978 switch (event) { 2979 case NETDEV_RESEND_IGMP: 2980 in_dev = __in_dev_get_rtnl(dev); 2981 if (in_dev) 2982 ip_mc_rejoin_groups(in_dev); 2983 break; 2984 default: 2985 break; 2986 } 2987 return NOTIFY_DONE; 2988 } 2989 2990 static struct notifier_block igmp_notifier = { 2991 .notifier_call = igmp_netdev_event, 2992 }; 2993 2994 int __init igmp_mc_init(void) 2995 { 2996 #if defined(CONFIG_PROC_FS) 2997 int err; 2998 2999 err = register_pernet_subsys(&igmp_net_ops); 3000 if (err) 3001 return err; 3002 err = register_netdevice_notifier(&igmp_notifier); 3003 if (err) 3004 goto reg_notif_fail; 3005 return 0; 3006 3007 reg_notif_fail: 3008 unregister_pernet_subsys(&igmp_net_ops); 3009 return err; 3010 #else 3011 return register_netdevice_notifier(&igmp_notifier); 3012 #endif 3013 } 3014