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