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