1 /* 2 * Linux NET3: Internet Group Management Protocol [IGMP] 3 * 4 * This code implements the IGMP protocol as defined in RFC1112. There has 5 * been a further revision of this protocol since which is now supported. 6 * 7 * If you have trouble with this module be careful what gcc you have used, 8 * the older version didn't come out right using gcc 2.5.8, the newer one 9 * seems to fall out with gcc 2.6.2. 10 * 11 * Authors: 12 * Alan Cox <alan@lxorguk.ukuu.org.uk> 13 * 14 * This program is free software; you can redistribute it and/or 15 * modify it under the terms of the GNU General Public License 16 * as published by the Free Software Foundation; either version 17 * 2 of the License, or (at your option) any later version. 18 * 19 * Fixes: 20 * 21 * Alan Cox : Added lots of __inline__ to optimise 22 * the memory usage of all the tiny little 23 * functions. 24 * Alan Cox : Dumped the header building experiment. 25 * Alan Cox : Minor tweaks ready for multicast routing 26 * and extended IGMP protocol. 27 * Alan Cox : Removed a load of inline directives. Gcc 2.5.8 28 * writes utterly bogus code otherwise (sigh) 29 * fixed IGMP loopback to behave in the manner 30 * desired by mrouted, fixed the fact it has been 31 * broken since 1.3.6 and cleaned up a few minor 32 * points. 33 * 34 * Chih-Jen Chang : Tried to revise IGMP to Version 2 35 * Tsu-Sheng Tsao E-mail: chihjenc@scf.usc.edu and tsusheng@scf.usc.edu 36 * The enhancements are mainly based on Steve Deering's 37 * ipmulti-3.5 source code. 38 * Chih-Jen Chang : Added the igmp_get_mrouter_info and 39 * Tsu-Sheng Tsao igmp_set_mrouter_info to keep track of 40 * the mrouted version on that device. 41 * Chih-Jen Chang : Added the max_resp_time parameter to 42 * Tsu-Sheng Tsao igmp_heard_query(). Using this parameter 43 * to identify the multicast router version 44 * and do what the IGMP version 2 specified. 45 * Chih-Jen Chang : Added a timer to revert to IGMP V2 router 46 * Tsu-Sheng Tsao if the specified time expired. 47 * Alan Cox : Stop IGMP from 0.0.0.0 being accepted. 48 * Alan Cox : Use GFP_ATOMIC in the right places. 49 * Christian Daudt : igmp timer wasn't set for local group 50 * memberships but was being deleted, 51 * which caused a "del_timer() called 52 * from %p with timer not initialized\n" 53 * message (960131). 54 * Christian Daudt : removed del_timer from 55 * igmp_timer_expire function (960205). 56 * Christian Daudt : igmp_heard_report now only calls 57 * igmp_timer_expire if tm->running is 58 * true (960216). 59 * Malcolm Beattie : ttl comparison wrong in igmp_rcv made 60 * igmp_heard_query never trigger. Expiry 61 * miscalculation fixed in igmp_heard_query 62 * and random() made to return unsigned to 63 * prevent negative expiry times. 64 * Alexey Kuznetsov: Wrong group leaving behaviour, backport 65 * fix from pending 2.1.x patches. 66 * Alan Cox: Forget to enable FDDI support earlier. 67 * Alexey Kuznetsov: Fixed leaving groups on device down. 68 * Alexey Kuznetsov: Accordance to igmp-v2-06 draft. 69 * David L Stevens: IGMPv3 support, with help from 70 * Vinay Kulkarni 71 */ 72 73 #include <linux/module.h> 74 #include <linux/slab.h> 75 #include <linux/uaccess.h> 76 #include <linux/types.h> 77 #include <linux/kernel.h> 78 #include <linux/jiffies.h> 79 #include <linux/string.h> 80 #include <linux/socket.h> 81 #include <linux/sockios.h> 82 #include <linux/in.h> 83 #include <linux/inet.h> 84 #include <linux/netdevice.h> 85 #include <linux/skbuff.h> 86 #include <linux/inetdevice.h> 87 #include <linux/igmp.h> 88 #include <linux/if_arp.h> 89 #include <linux/rtnetlink.h> 90 #include <linux/times.h> 91 #include <linux/pkt_sched.h> 92 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, struct ip_mc_list *im); 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 (refcount_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 refcount_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 refcount_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 unsigned long exp = jiffies + tv + 2; 223 224 if (in_dev->mr_gq_running && 225 time_after_eq(exp, (in_dev->mr_gq_timer).expires)) 226 return; 227 228 in_dev->mr_gq_running = 1; 229 if (!mod_timer(&in_dev->mr_gq_timer, exp)) 230 in_dev_hold(in_dev); 231 } 232 233 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay) 234 { 235 int tv = prandom_u32() % delay; 236 237 if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2)) 238 in_dev_hold(in_dev); 239 } 240 241 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay) 242 { 243 spin_lock_bh(&im->lock); 244 im->unsolicit_count = 0; 245 if (del_timer(&im->timer)) { 246 if ((long)(im->timer.expires-jiffies) < max_delay) { 247 add_timer(&im->timer); 248 im->tm_running = 1; 249 spin_unlock_bh(&im->lock); 250 return; 251 } 252 refcount_dec(&im->refcnt); 253 } 254 igmp_start_timer(im, max_delay); 255 spin_unlock_bh(&im->lock); 256 } 257 258 259 /* 260 * Send an IGMP report. 261 */ 262 263 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4) 264 265 266 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type, 267 int gdeleted, int sdeleted) 268 { 269 switch (type) { 270 case IGMPV3_MODE_IS_INCLUDE: 271 case IGMPV3_MODE_IS_EXCLUDE: 272 if (gdeleted || sdeleted) 273 return 0; 274 if (!(pmc->gsquery && !psf->sf_gsresp)) { 275 if (pmc->sfmode == MCAST_INCLUDE) 276 return 1; 277 /* don't include if this source is excluded 278 * in all filters 279 */ 280 if (psf->sf_count[MCAST_INCLUDE]) 281 return type == IGMPV3_MODE_IS_INCLUDE; 282 return pmc->sfcount[MCAST_EXCLUDE] == 283 psf->sf_count[MCAST_EXCLUDE]; 284 } 285 return 0; 286 case IGMPV3_CHANGE_TO_INCLUDE: 287 if (gdeleted || sdeleted) 288 return 0; 289 return psf->sf_count[MCAST_INCLUDE] != 0; 290 case IGMPV3_CHANGE_TO_EXCLUDE: 291 if (gdeleted || sdeleted) 292 return 0; 293 if (pmc->sfcount[MCAST_EXCLUDE] == 0 || 294 psf->sf_count[MCAST_INCLUDE]) 295 return 0; 296 return pmc->sfcount[MCAST_EXCLUDE] == 297 psf->sf_count[MCAST_EXCLUDE]; 298 case IGMPV3_ALLOW_NEW_SOURCES: 299 if (gdeleted || !psf->sf_crcount) 300 return 0; 301 return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted; 302 case IGMPV3_BLOCK_OLD_SOURCES: 303 if (pmc->sfmode == MCAST_INCLUDE) 304 return gdeleted || (psf->sf_crcount && sdeleted); 305 return psf->sf_crcount && !gdeleted && !sdeleted; 306 } 307 return 0; 308 } 309 310 static int 311 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted) 312 { 313 struct ip_sf_list *psf; 314 int scount = 0; 315 316 for (psf = pmc->sources; psf; psf = psf->sf_next) { 317 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) 318 continue; 319 scount++; 320 } 321 return scount; 322 } 323 324 static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu) 325 { 326 struct sk_buff *skb; 327 struct rtable *rt; 328 struct iphdr *pip; 329 struct igmpv3_report *pig; 330 struct net *net = dev_net(dev); 331 struct flowi4 fl4; 332 int hlen = LL_RESERVED_SPACE(dev); 333 int tlen = dev->needed_tailroom; 334 unsigned int size = mtu; 335 336 while (1) { 337 skb = alloc_skb(size + hlen + tlen, 338 GFP_ATOMIC | __GFP_NOWARN); 339 if (skb) 340 break; 341 size >>= 1; 342 if (size < 256) 343 return NULL; 344 } 345 skb->priority = TC_PRIO_CONTROL; 346 347 rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0, 348 0, 0, 349 IPPROTO_IGMP, 0, dev->ifindex); 350 if (IS_ERR(rt)) { 351 kfree_skb(skb); 352 return NULL; 353 } 354 355 skb_dst_set(skb, &rt->dst); 356 skb->dev = dev; 357 358 skb_reserve(skb, hlen); 359 skb_tailroom_reserve(skb, mtu, tlen); 360 361 skb_reset_network_header(skb); 362 pip = ip_hdr(skb); 363 skb_put(skb, sizeof(struct iphdr) + 4); 364 365 pip->version = 4; 366 pip->ihl = (sizeof(struct iphdr)+4)>>2; 367 pip->tos = 0xc0; 368 pip->frag_off = htons(IP_DF); 369 pip->ttl = 1; 370 pip->daddr = fl4.daddr; 371 pip->saddr = fl4.saddr; 372 pip->protocol = IPPROTO_IGMP; 373 pip->tot_len = 0; /* filled in later */ 374 ip_select_ident(net, skb, NULL); 375 ((u8 *)&pip[1])[0] = IPOPT_RA; 376 ((u8 *)&pip[1])[1] = 4; 377 ((u8 *)&pip[1])[2] = 0; 378 ((u8 *)&pip[1])[3] = 0; 379 380 skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4; 381 skb_put(skb, sizeof(*pig)); 382 pig = igmpv3_report_hdr(skb); 383 pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT; 384 pig->resv1 = 0; 385 pig->csum = 0; 386 pig->resv2 = 0; 387 pig->ngrec = 0; 388 return skb; 389 } 390 391 static int igmpv3_sendpack(struct sk_buff *skb) 392 { 393 struct igmphdr *pig = igmp_hdr(skb); 394 const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb); 395 396 pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen); 397 398 return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb); 399 } 400 401 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel) 402 { 403 return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel); 404 } 405 406 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc, 407 int type, struct igmpv3_grec **ppgr, unsigned int mtu) 408 { 409 struct net_device *dev = pmc->interface->dev; 410 struct igmpv3_report *pih; 411 struct igmpv3_grec *pgr; 412 413 if (!skb) { 414 skb = igmpv3_newpack(dev, mtu); 415 if (!skb) 416 return NULL; 417 } 418 pgr = skb_put(skb, sizeof(struct igmpv3_grec)); 419 pgr->grec_type = type; 420 pgr->grec_auxwords = 0; 421 pgr->grec_nsrcs = 0; 422 pgr->grec_mca = pmc->multiaddr; 423 pih = igmpv3_report_hdr(skb); 424 pih->ngrec = htons(ntohs(pih->ngrec)+1); 425 *ppgr = pgr; 426 return skb; 427 } 428 429 #define AVAILABLE(skb) ((skb) ? skb_availroom(skb) : 0) 430 431 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc, 432 int type, int gdeleted, int sdeleted) 433 { 434 struct net_device *dev = pmc->interface->dev; 435 struct net *net = dev_net(dev); 436 struct igmpv3_report *pih; 437 struct igmpv3_grec *pgr = NULL; 438 struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list; 439 int scount, stotal, first, isquery, truncate; 440 unsigned int mtu; 441 442 if (pmc->multiaddr == IGMP_ALL_HOSTS) 443 return skb; 444 if (ipv4_is_local_multicast(pmc->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports) 445 return skb; 446 447 mtu = READ_ONCE(dev->mtu); 448 if (mtu < IPV4_MIN_MTU) 449 return skb; 450 451 isquery = type == IGMPV3_MODE_IS_INCLUDE || 452 type == IGMPV3_MODE_IS_EXCLUDE; 453 truncate = type == IGMPV3_MODE_IS_EXCLUDE || 454 type == IGMPV3_CHANGE_TO_EXCLUDE; 455 456 stotal = scount = 0; 457 458 psf_list = sdeleted ? &pmc->tomb : &pmc->sources; 459 460 if (!*psf_list) 461 goto empty_source; 462 463 pih = skb ? igmpv3_report_hdr(skb) : NULL; 464 465 /* EX and TO_EX get a fresh packet, if needed */ 466 if (truncate) { 467 if (pih && pih->ngrec && 468 AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) { 469 if (skb) 470 igmpv3_sendpack(skb); 471 skb = igmpv3_newpack(dev, mtu); 472 } 473 } 474 first = 1; 475 psf_prev = NULL; 476 for (psf = *psf_list; psf; psf = psf_next) { 477 __be32 *psrc; 478 479 psf_next = psf->sf_next; 480 481 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) { 482 psf_prev = psf; 483 continue; 484 } 485 486 /* Based on RFC3376 5.1. Should not send source-list change 487 * records when there is a filter mode change. 488 */ 489 if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) || 490 (!gdeleted && pmc->crcount)) && 491 (type == IGMPV3_ALLOW_NEW_SOURCES || 492 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) 493 goto decrease_sf_crcount; 494 495 /* clear marks on query responses */ 496 if (isquery) 497 psf->sf_gsresp = 0; 498 499 if (AVAILABLE(skb) < sizeof(__be32) + 500 first*sizeof(struct igmpv3_grec)) { 501 if (truncate && !first) 502 break; /* truncate these */ 503 if (pgr) 504 pgr->grec_nsrcs = htons(scount); 505 if (skb) 506 igmpv3_sendpack(skb); 507 skb = igmpv3_newpack(dev, mtu); 508 first = 1; 509 scount = 0; 510 } 511 if (first) { 512 skb = add_grhead(skb, pmc, type, &pgr, mtu); 513 first = 0; 514 } 515 if (!skb) 516 return NULL; 517 psrc = skb_put(skb, sizeof(__be32)); 518 *psrc = psf->sf_inaddr; 519 scount++; stotal++; 520 if ((type == IGMPV3_ALLOW_NEW_SOURCES || 521 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) { 522 decrease_sf_crcount: 523 psf->sf_crcount--; 524 if ((sdeleted || gdeleted) && psf->sf_crcount == 0) { 525 if (psf_prev) 526 psf_prev->sf_next = psf->sf_next; 527 else 528 *psf_list = psf->sf_next; 529 kfree(psf); 530 continue; 531 } 532 } 533 psf_prev = psf; 534 } 535 536 empty_source: 537 if (!stotal) { 538 if (type == IGMPV3_ALLOW_NEW_SOURCES || 539 type == IGMPV3_BLOCK_OLD_SOURCES) 540 return skb; 541 if (pmc->crcount || isquery) { 542 /* make sure we have room for group header */ 543 if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) { 544 igmpv3_sendpack(skb); 545 skb = NULL; /* add_grhead will get a new one */ 546 } 547 skb = add_grhead(skb, pmc, type, &pgr, mtu); 548 } 549 } 550 if (pgr) 551 pgr->grec_nsrcs = htons(scount); 552 553 if (isquery) 554 pmc->gsquery = 0; /* clear query state on report */ 555 return skb; 556 } 557 558 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc) 559 { 560 struct sk_buff *skb = NULL; 561 struct net *net = dev_net(in_dev->dev); 562 int type; 563 564 if (!pmc) { 565 rcu_read_lock(); 566 for_each_pmc_rcu(in_dev, pmc) { 567 if (pmc->multiaddr == IGMP_ALL_HOSTS) 568 continue; 569 if (ipv4_is_local_multicast(pmc->multiaddr) && 570 !net->ipv4.sysctl_igmp_llm_reports) 571 continue; 572 spin_lock_bh(&pmc->lock); 573 if (pmc->sfcount[MCAST_EXCLUDE]) 574 type = IGMPV3_MODE_IS_EXCLUDE; 575 else 576 type = IGMPV3_MODE_IS_INCLUDE; 577 skb = add_grec(skb, pmc, type, 0, 0); 578 spin_unlock_bh(&pmc->lock); 579 } 580 rcu_read_unlock(); 581 } else { 582 spin_lock_bh(&pmc->lock); 583 if (pmc->sfcount[MCAST_EXCLUDE]) 584 type = IGMPV3_MODE_IS_EXCLUDE; 585 else 586 type = IGMPV3_MODE_IS_INCLUDE; 587 skb = add_grec(skb, pmc, type, 0, 0); 588 spin_unlock_bh(&pmc->lock); 589 } 590 if (!skb) 591 return 0; 592 return igmpv3_sendpack(skb); 593 } 594 595 /* 596 * remove zero-count source records from a source filter list 597 */ 598 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf) 599 { 600 struct ip_sf_list *psf_prev, *psf_next, *psf; 601 602 psf_prev = NULL; 603 for (psf = *ppsf; psf; psf = psf_next) { 604 psf_next = psf->sf_next; 605 if (psf->sf_crcount == 0) { 606 if (psf_prev) 607 psf_prev->sf_next = psf->sf_next; 608 else 609 *ppsf = psf->sf_next; 610 kfree(psf); 611 } else 612 psf_prev = psf; 613 } 614 } 615 616 static void igmpv3_send_cr(struct in_device *in_dev) 617 { 618 struct ip_mc_list *pmc, *pmc_prev, *pmc_next; 619 struct sk_buff *skb = NULL; 620 int type, dtype; 621 622 rcu_read_lock(); 623 spin_lock_bh(&in_dev->mc_tomb_lock); 624 625 /* deleted MCA's */ 626 pmc_prev = NULL; 627 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) { 628 pmc_next = pmc->next; 629 if (pmc->sfmode == MCAST_INCLUDE) { 630 type = IGMPV3_BLOCK_OLD_SOURCES; 631 dtype = IGMPV3_BLOCK_OLD_SOURCES; 632 skb = add_grec(skb, pmc, type, 1, 0); 633 skb = add_grec(skb, pmc, dtype, 1, 1); 634 } 635 if (pmc->crcount) { 636 if (pmc->sfmode == MCAST_EXCLUDE) { 637 type = IGMPV3_CHANGE_TO_INCLUDE; 638 skb = add_grec(skb, pmc, type, 1, 0); 639 } 640 pmc->crcount--; 641 if (pmc->crcount == 0) { 642 igmpv3_clear_zeros(&pmc->tomb); 643 igmpv3_clear_zeros(&pmc->sources); 644 } 645 } 646 if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) { 647 if (pmc_prev) 648 pmc_prev->next = pmc_next; 649 else 650 in_dev->mc_tomb = pmc_next; 651 in_dev_put(pmc->interface); 652 kfree(pmc); 653 } else 654 pmc_prev = pmc; 655 } 656 spin_unlock_bh(&in_dev->mc_tomb_lock); 657 658 /* change recs */ 659 for_each_pmc_rcu(in_dev, pmc) { 660 spin_lock_bh(&pmc->lock); 661 if (pmc->sfcount[MCAST_EXCLUDE]) { 662 type = IGMPV3_BLOCK_OLD_SOURCES; 663 dtype = IGMPV3_ALLOW_NEW_SOURCES; 664 } else { 665 type = IGMPV3_ALLOW_NEW_SOURCES; 666 dtype = IGMPV3_BLOCK_OLD_SOURCES; 667 } 668 skb = add_grec(skb, pmc, type, 0, 0); 669 skb = add_grec(skb, pmc, dtype, 0, 1); /* deleted sources */ 670 671 /* filter mode changes */ 672 if (pmc->crcount) { 673 if (pmc->sfmode == MCAST_EXCLUDE) 674 type = IGMPV3_CHANGE_TO_EXCLUDE; 675 else 676 type = IGMPV3_CHANGE_TO_INCLUDE; 677 skb = add_grec(skb, pmc, type, 0, 0); 678 pmc->crcount--; 679 } 680 spin_unlock_bh(&pmc->lock); 681 } 682 rcu_read_unlock(); 683 684 if (!skb) 685 return; 686 (void) igmpv3_sendpack(skb); 687 } 688 689 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc, 690 int type) 691 { 692 struct sk_buff *skb; 693 struct iphdr *iph; 694 struct igmphdr *ih; 695 struct rtable *rt; 696 struct net_device *dev = in_dev->dev; 697 struct net *net = dev_net(dev); 698 __be32 group = pmc ? pmc->multiaddr : 0; 699 struct flowi4 fl4; 700 __be32 dst; 701 int hlen, tlen; 702 703 if (type == IGMPV3_HOST_MEMBERSHIP_REPORT) 704 return igmpv3_send_report(in_dev, pmc); 705 706 if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports) 707 return 0; 708 709 if (type == IGMP_HOST_LEAVE_MESSAGE) 710 dst = IGMP_ALL_ROUTER; 711 else 712 dst = group; 713 714 rt = ip_route_output_ports(net, &fl4, NULL, dst, 0, 715 0, 0, 716 IPPROTO_IGMP, 0, dev->ifindex); 717 if (IS_ERR(rt)) 718 return -1; 719 720 hlen = LL_RESERVED_SPACE(dev); 721 tlen = dev->needed_tailroom; 722 skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC); 723 if (!skb) { 724 ip_rt_put(rt); 725 return -1; 726 } 727 skb->priority = TC_PRIO_CONTROL; 728 729 skb_dst_set(skb, &rt->dst); 730 731 skb_reserve(skb, hlen); 732 733 skb_reset_network_header(skb); 734 iph = ip_hdr(skb); 735 skb_put(skb, sizeof(struct iphdr) + 4); 736 737 iph->version = 4; 738 iph->ihl = (sizeof(struct iphdr)+4)>>2; 739 iph->tos = 0xc0; 740 iph->frag_off = htons(IP_DF); 741 iph->ttl = 1; 742 iph->daddr = dst; 743 iph->saddr = fl4.saddr; 744 iph->protocol = IPPROTO_IGMP; 745 ip_select_ident(net, skb, NULL); 746 ((u8 *)&iph[1])[0] = IPOPT_RA; 747 ((u8 *)&iph[1])[1] = 4; 748 ((u8 *)&iph[1])[2] = 0; 749 ((u8 *)&iph[1])[3] = 0; 750 751 ih = skb_put(skb, sizeof(struct igmphdr)); 752 ih->type = type; 753 ih->code = 0; 754 ih->csum = 0; 755 ih->group = group; 756 ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr)); 757 758 return ip_local_out(net, skb->sk, skb); 759 } 760 761 static void igmp_gq_timer_expire(struct timer_list *t) 762 { 763 struct in_device *in_dev = from_timer(in_dev, t, mr_gq_timer); 764 765 in_dev->mr_gq_running = 0; 766 igmpv3_send_report(in_dev, NULL); 767 in_dev_put(in_dev); 768 } 769 770 static void igmp_ifc_timer_expire(struct timer_list *t) 771 { 772 struct in_device *in_dev = from_timer(in_dev, t, mr_ifc_timer); 773 774 igmpv3_send_cr(in_dev); 775 if (in_dev->mr_ifc_count) { 776 in_dev->mr_ifc_count--; 777 igmp_ifc_start_timer(in_dev, 778 unsolicited_report_interval(in_dev)); 779 } 780 in_dev_put(in_dev); 781 } 782 783 static void igmp_ifc_event(struct in_device *in_dev) 784 { 785 struct net *net = dev_net(in_dev->dev); 786 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) 787 return; 788 in_dev->mr_ifc_count = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 789 igmp_ifc_start_timer(in_dev, 1); 790 } 791 792 793 static void igmp_timer_expire(struct timer_list *t) 794 { 795 struct ip_mc_list *im = from_timer(im, t, timer); 796 struct in_device *in_dev = im->interface; 797 798 spin_lock(&im->lock); 799 im->tm_running = 0; 800 801 if (im->unsolicit_count) { 802 im->unsolicit_count--; 803 igmp_start_timer(im, unsolicited_report_interval(in_dev)); 804 } 805 im->reporter = 1; 806 spin_unlock(&im->lock); 807 808 if (IGMP_V1_SEEN(in_dev)) 809 igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT); 810 else if (IGMP_V2_SEEN(in_dev)) 811 igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT); 812 else 813 igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT); 814 815 ip_ma_put(im); 816 } 817 818 /* mark EXCLUDE-mode sources */ 819 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs) 820 { 821 struct ip_sf_list *psf; 822 int i, scount; 823 824 scount = 0; 825 for (psf = pmc->sources; psf; psf = psf->sf_next) { 826 if (scount == nsrcs) 827 break; 828 for (i = 0; i < nsrcs; i++) { 829 /* skip inactive filters */ 830 if (psf->sf_count[MCAST_INCLUDE] || 831 pmc->sfcount[MCAST_EXCLUDE] != 832 psf->sf_count[MCAST_EXCLUDE]) 833 break; 834 if (srcs[i] == psf->sf_inaddr) { 835 scount++; 836 break; 837 } 838 } 839 } 840 pmc->gsquery = 0; 841 if (scount == nsrcs) /* all sources excluded */ 842 return 0; 843 return 1; 844 } 845 846 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs) 847 { 848 struct ip_sf_list *psf; 849 int i, scount; 850 851 if (pmc->sfmode == MCAST_EXCLUDE) 852 return igmp_xmarksources(pmc, nsrcs, srcs); 853 854 /* mark INCLUDE-mode sources */ 855 scount = 0; 856 for (psf = pmc->sources; psf; psf = psf->sf_next) { 857 if (scount == nsrcs) 858 break; 859 for (i = 0; i < nsrcs; i++) 860 if (srcs[i] == psf->sf_inaddr) { 861 psf->sf_gsresp = 1; 862 scount++; 863 break; 864 } 865 } 866 if (!scount) { 867 pmc->gsquery = 0; 868 return 0; 869 } 870 pmc->gsquery = 1; 871 return 1; 872 } 873 874 /* return true if packet was dropped */ 875 static bool igmp_heard_report(struct in_device *in_dev, __be32 group) 876 { 877 struct ip_mc_list *im; 878 struct net *net = dev_net(in_dev->dev); 879 880 /* Timers are only set for non-local groups */ 881 882 if (group == IGMP_ALL_HOSTS) 883 return false; 884 if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports) 885 return false; 886 887 rcu_read_lock(); 888 for_each_pmc_rcu(in_dev, im) { 889 if (im->multiaddr == group) { 890 igmp_stop_timer(im); 891 break; 892 } 893 } 894 rcu_read_unlock(); 895 return false; 896 } 897 898 /* return true if packet was dropped */ 899 static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb, 900 int len) 901 { 902 struct igmphdr *ih = igmp_hdr(skb); 903 struct igmpv3_query *ih3 = igmpv3_query_hdr(skb); 904 struct ip_mc_list *im; 905 __be32 group = ih->group; 906 int max_delay; 907 int mark = 0; 908 struct net *net = dev_net(in_dev->dev); 909 910 911 if (len == 8) { 912 if (ih->code == 0) { 913 /* Alas, old v1 router presents here. */ 914 915 max_delay = IGMP_QUERY_RESPONSE_INTERVAL; 916 in_dev->mr_v1_seen = jiffies + 917 IGMP_V1_ROUTER_PRESENT_TIMEOUT; 918 group = 0; 919 } else { 920 /* v2 router present */ 921 max_delay = ih->code*(HZ/IGMP_TIMER_SCALE); 922 in_dev->mr_v2_seen = jiffies + 923 IGMP_V2_ROUTER_PRESENT_TIMEOUT; 924 } 925 /* cancel the interface change timer */ 926 in_dev->mr_ifc_count = 0; 927 if (del_timer(&in_dev->mr_ifc_timer)) 928 __in_dev_put(in_dev); 929 /* clear deleted report items */ 930 igmpv3_clear_delrec(in_dev); 931 } else if (len < 12) { 932 return true; /* ignore bogus packet; freed by caller */ 933 } else if (IGMP_V1_SEEN(in_dev)) { 934 /* This is a v3 query with v1 queriers present */ 935 max_delay = IGMP_QUERY_RESPONSE_INTERVAL; 936 group = 0; 937 } else if (IGMP_V2_SEEN(in_dev)) { 938 /* this is a v3 query with v2 queriers present; 939 * Interpretation of the max_delay code is problematic here. 940 * A real v2 host would use ih_code directly, while v3 has a 941 * different encoding. We use the v3 encoding as more likely 942 * to be intended in a v3 query. 943 */ 944 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE); 945 if (!max_delay) 946 max_delay = 1; /* can't mod w/ 0 */ 947 } else { /* v3 */ 948 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) 949 return true; 950 951 ih3 = igmpv3_query_hdr(skb); 952 if (ih3->nsrcs) { 953 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query) 954 + ntohs(ih3->nsrcs)*sizeof(__be32))) 955 return true; 956 ih3 = igmpv3_query_hdr(skb); 957 } 958 959 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE); 960 if (!max_delay) 961 max_delay = 1; /* can't mod w/ 0 */ 962 in_dev->mr_maxdelay = max_delay; 963 if (ih3->qrv) 964 in_dev->mr_qrv = ih3->qrv; 965 if (!group) { /* general query */ 966 if (ih3->nsrcs) 967 return true; /* no sources allowed */ 968 igmp_gq_start_timer(in_dev); 969 return false; 970 } 971 /* mark sources to include, if group & source-specific */ 972 mark = ih3->nsrcs != 0; 973 } 974 975 /* 976 * - Start the timers in all of our membership records 977 * that the query applies to for the interface on 978 * which the query arrived excl. those that belong 979 * to a "local" group (224.0.0.X) 980 * - For timers already running check if they need to 981 * be reset. 982 * - Use the igmp->igmp_code field as the maximum 983 * delay possible 984 */ 985 rcu_read_lock(); 986 for_each_pmc_rcu(in_dev, im) { 987 int changed; 988 989 if (group && group != im->multiaddr) 990 continue; 991 if (im->multiaddr == IGMP_ALL_HOSTS) 992 continue; 993 if (ipv4_is_local_multicast(im->multiaddr) && 994 !net->ipv4.sysctl_igmp_llm_reports) 995 continue; 996 spin_lock_bh(&im->lock); 997 if (im->tm_running) 998 im->gsquery = im->gsquery && mark; 999 else 1000 im->gsquery = mark; 1001 changed = !im->gsquery || 1002 igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs); 1003 spin_unlock_bh(&im->lock); 1004 if (changed) 1005 igmp_mod_timer(im, max_delay); 1006 } 1007 rcu_read_unlock(); 1008 return false; 1009 } 1010 1011 /* called in rcu_read_lock() section */ 1012 int igmp_rcv(struct sk_buff *skb) 1013 { 1014 /* This basically follows the spec line by line -- see RFC1112 */ 1015 struct igmphdr *ih; 1016 struct net_device *dev = skb->dev; 1017 struct in_device *in_dev; 1018 int len = skb->len; 1019 bool dropped = true; 1020 1021 if (netif_is_l3_master(dev)) { 1022 dev = dev_get_by_index_rcu(dev_net(dev), IPCB(skb)->iif); 1023 if (!dev) 1024 goto drop; 1025 } 1026 1027 in_dev = __in_dev_get_rcu(dev); 1028 if (!in_dev) 1029 goto drop; 1030 1031 if (!pskb_may_pull(skb, sizeof(struct igmphdr))) 1032 goto drop; 1033 1034 if (skb_checksum_simple_validate(skb)) 1035 goto drop; 1036 1037 ih = igmp_hdr(skb); 1038 switch (ih->type) { 1039 case IGMP_HOST_MEMBERSHIP_QUERY: 1040 dropped = igmp_heard_query(in_dev, skb, len); 1041 break; 1042 case IGMP_HOST_MEMBERSHIP_REPORT: 1043 case IGMPV2_HOST_MEMBERSHIP_REPORT: 1044 /* Is it our report looped back? */ 1045 if (rt_is_output_route(skb_rtable(skb))) 1046 break; 1047 /* don't rely on MC router hearing unicast reports */ 1048 if (skb->pkt_type == PACKET_MULTICAST || 1049 skb->pkt_type == PACKET_BROADCAST) 1050 dropped = igmp_heard_report(in_dev, ih->group); 1051 break; 1052 case IGMP_PIM: 1053 #ifdef CONFIG_IP_PIMSM_V1 1054 return pim_rcv_v1(skb); 1055 #endif 1056 case IGMPV3_HOST_MEMBERSHIP_REPORT: 1057 case IGMP_DVMRP: 1058 case IGMP_TRACE: 1059 case IGMP_HOST_LEAVE_MESSAGE: 1060 case IGMP_MTRACE: 1061 case IGMP_MTRACE_RESP: 1062 break; 1063 default: 1064 break; 1065 } 1066 1067 drop: 1068 if (dropped) 1069 kfree_skb(skb); 1070 else 1071 consume_skb(skb); 1072 return 0; 1073 } 1074 1075 #endif 1076 1077 1078 /* 1079 * Add a filter to a device 1080 */ 1081 1082 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr) 1083 { 1084 char buf[MAX_ADDR_LEN]; 1085 struct net_device *dev = in_dev->dev; 1086 1087 /* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG. 1088 We will get multicast token leakage, when IFF_MULTICAST 1089 is changed. This check should be done in ndo_set_rx_mode 1090 routine. Something sort of: 1091 if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; } 1092 --ANK 1093 */ 1094 if (arp_mc_map(addr, buf, dev, 0) == 0) 1095 dev_mc_add(dev, buf); 1096 } 1097 1098 /* 1099 * Remove a filter from a device 1100 */ 1101 1102 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr) 1103 { 1104 char buf[MAX_ADDR_LEN]; 1105 struct net_device *dev = in_dev->dev; 1106 1107 if (arp_mc_map(addr, buf, dev, 0) == 0) 1108 dev_mc_del(dev, buf); 1109 } 1110 1111 #ifdef CONFIG_IP_MULTICAST 1112 /* 1113 * deleted ip_mc_list manipulation 1114 */ 1115 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im) 1116 { 1117 struct ip_mc_list *pmc; 1118 struct net *net = dev_net(in_dev->dev); 1119 1120 /* this is an "ip_mc_list" for convenience; only the fields below 1121 * are actually used. In particular, the refcnt and users are not 1122 * used for management of the delete list. Using the same structure 1123 * for deleted items allows change reports to use common code with 1124 * non-deleted or query-response MCA's. 1125 */ 1126 pmc = kzalloc(sizeof(*pmc), GFP_KERNEL); 1127 if (!pmc) 1128 return; 1129 spin_lock_init(&pmc->lock); 1130 spin_lock_bh(&im->lock); 1131 pmc->interface = im->interface; 1132 in_dev_hold(in_dev); 1133 pmc->multiaddr = im->multiaddr; 1134 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1135 pmc->sfmode = im->sfmode; 1136 if (pmc->sfmode == MCAST_INCLUDE) { 1137 struct ip_sf_list *psf; 1138 1139 pmc->tomb = im->tomb; 1140 pmc->sources = im->sources; 1141 im->tomb = im->sources = NULL; 1142 for (psf = pmc->sources; psf; psf = psf->sf_next) 1143 psf->sf_crcount = pmc->crcount; 1144 } 1145 spin_unlock_bh(&im->lock); 1146 1147 spin_lock_bh(&in_dev->mc_tomb_lock); 1148 pmc->next = in_dev->mc_tomb; 1149 in_dev->mc_tomb = pmc; 1150 spin_unlock_bh(&in_dev->mc_tomb_lock); 1151 } 1152 1153 /* 1154 * restore ip_mc_list deleted records 1155 */ 1156 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im) 1157 { 1158 struct ip_mc_list *pmc, *pmc_prev; 1159 struct ip_sf_list *psf; 1160 struct net *net = dev_net(in_dev->dev); 1161 __be32 multiaddr = im->multiaddr; 1162 1163 spin_lock_bh(&in_dev->mc_tomb_lock); 1164 pmc_prev = NULL; 1165 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) { 1166 if (pmc->multiaddr == multiaddr) 1167 break; 1168 pmc_prev = pmc; 1169 } 1170 if (pmc) { 1171 if (pmc_prev) 1172 pmc_prev->next = pmc->next; 1173 else 1174 in_dev->mc_tomb = pmc->next; 1175 } 1176 spin_unlock_bh(&in_dev->mc_tomb_lock); 1177 1178 spin_lock_bh(&im->lock); 1179 if (pmc) { 1180 im->interface = pmc->interface; 1181 im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1182 im->sfmode = pmc->sfmode; 1183 if (pmc->sfmode == MCAST_INCLUDE) { 1184 im->tomb = pmc->tomb; 1185 im->sources = pmc->sources; 1186 for (psf = im->sources; psf; psf = psf->sf_next) 1187 psf->sf_crcount = im->crcount; 1188 } 1189 in_dev_put(pmc->interface); 1190 kfree(pmc); 1191 } 1192 spin_unlock_bh(&im->lock); 1193 } 1194 1195 /* 1196 * flush ip_mc_list deleted records 1197 */ 1198 static void igmpv3_clear_delrec(struct in_device *in_dev) 1199 { 1200 struct ip_mc_list *pmc, *nextpmc; 1201 1202 spin_lock_bh(&in_dev->mc_tomb_lock); 1203 pmc = in_dev->mc_tomb; 1204 in_dev->mc_tomb = NULL; 1205 spin_unlock_bh(&in_dev->mc_tomb_lock); 1206 1207 for (; pmc; pmc = nextpmc) { 1208 nextpmc = pmc->next; 1209 ip_mc_clear_src(pmc); 1210 in_dev_put(pmc->interface); 1211 kfree(pmc); 1212 } 1213 /* clear dead sources, too */ 1214 rcu_read_lock(); 1215 for_each_pmc_rcu(in_dev, pmc) { 1216 struct ip_sf_list *psf, *psf_next; 1217 1218 spin_lock_bh(&pmc->lock); 1219 psf = pmc->tomb; 1220 pmc->tomb = NULL; 1221 spin_unlock_bh(&pmc->lock); 1222 for (; psf; psf = psf_next) { 1223 psf_next = psf->sf_next; 1224 kfree(psf); 1225 } 1226 } 1227 rcu_read_unlock(); 1228 } 1229 #endif 1230 1231 static void igmp_group_dropped(struct ip_mc_list *im) 1232 { 1233 struct in_device *in_dev = im->interface; 1234 #ifdef CONFIG_IP_MULTICAST 1235 struct net *net = dev_net(in_dev->dev); 1236 int reporter; 1237 #endif 1238 1239 if (im->loaded) { 1240 im->loaded = 0; 1241 ip_mc_filter_del(in_dev, im->multiaddr); 1242 } 1243 1244 #ifdef CONFIG_IP_MULTICAST 1245 if (im->multiaddr == IGMP_ALL_HOSTS) 1246 return; 1247 if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports) 1248 return; 1249 1250 reporter = im->reporter; 1251 igmp_stop_timer(im); 1252 1253 if (!in_dev->dead) { 1254 if (IGMP_V1_SEEN(in_dev)) 1255 return; 1256 if (IGMP_V2_SEEN(in_dev)) { 1257 if (reporter) 1258 igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE); 1259 return; 1260 } 1261 /* IGMPv3 */ 1262 igmpv3_add_delrec(in_dev, im); 1263 1264 igmp_ifc_event(in_dev); 1265 } 1266 #endif 1267 } 1268 1269 static void igmp_group_added(struct ip_mc_list *im) 1270 { 1271 struct in_device *in_dev = im->interface; 1272 #ifdef CONFIG_IP_MULTICAST 1273 struct net *net = dev_net(in_dev->dev); 1274 #endif 1275 1276 if (im->loaded == 0) { 1277 im->loaded = 1; 1278 ip_mc_filter_add(in_dev, im->multiaddr); 1279 } 1280 1281 #ifdef CONFIG_IP_MULTICAST 1282 if (im->multiaddr == IGMP_ALL_HOSTS) 1283 return; 1284 if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports) 1285 return; 1286 1287 if (in_dev->dead) 1288 return; 1289 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) { 1290 spin_lock_bh(&im->lock); 1291 igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY); 1292 spin_unlock_bh(&im->lock); 1293 return; 1294 } 1295 /* else, v3 */ 1296 1297 im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1298 igmp_ifc_event(in_dev); 1299 #endif 1300 } 1301 1302 1303 /* 1304 * Multicast list managers 1305 */ 1306 1307 static u32 ip_mc_hash(const struct ip_mc_list *im) 1308 { 1309 return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG); 1310 } 1311 1312 static void ip_mc_hash_add(struct in_device *in_dev, 1313 struct ip_mc_list *im) 1314 { 1315 struct ip_mc_list __rcu **mc_hash; 1316 u32 hash; 1317 1318 mc_hash = rtnl_dereference(in_dev->mc_hash); 1319 if (mc_hash) { 1320 hash = ip_mc_hash(im); 1321 im->next_hash = mc_hash[hash]; 1322 rcu_assign_pointer(mc_hash[hash], im); 1323 return; 1324 } 1325 1326 /* do not use a hash table for small number of items */ 1327 if (in_dev->mc_count < 4) 1328 return; 1329 1330 mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG, 1331 GFP_KERNEL); 1332 if (!mc_hash) 1333 return; 1334 1335 for_each_pmc_rtnl(in_dev, im) { 1336 hash = ip_mc_hash(im); 1337 im->next_hash = mc_hash[hash]; 1338 RCU_INIT_POINTER(mc_hash[hash], im); 1339 } 1340 1341 rcu_assign_pointer(in_dev->mc_hash, mc_hash); 1342 } 1343 1344 static void ip_mc_hash_remove(struct in_device *in_dev, 1345 struct ip_mc_list *im) 1346 { 1347 struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash); 1348 struct ip_mc_list *aux; 1349 1350 if (!mc_hash) 1351 return; 1352 mc_hash += ip_mc_hash(im); 1353 while ((aux = rtnl_dereference(*mc_hash)) != im) 1354 mc_hash = &aux->next_hash; 1355 *mc_hash = im->next_hash; 1356 } 1357 1358 1359 /* 1360 * A socket has joined a multicast group on device dev. 1361 */ 1362 1363 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr) 1364 { 1365 struct ip_mc_list *im; 1366 #ifdef CONFIG_IP_MULTICAST 1367 struct net *net = dev_net(in_dev->dev); 1368 #endif 1369 1370 ASSERT_RTNL(); 1371 1372 for_each_pmc_rtnl(in_dev, im) { 1373 if (im->multiaddr == addr) { 1374 im->users++; 1375 ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0); 1376 goto out; 1377 } 1378 } 1379 1380 im = kzalloc(sizeof(*im), GFP_KERNEL); 1381 if (!im) 1382 goto out; 1383 1384 im->users = 1; 1385 im->interface = in_dev; 1386 in_dev_hold(in_dev); 1387 im->multiaddr = addr; 1388 /* initial mode is (EX, empty) */ 1389 im->sfmode = MCAST_EXCLUDE; 1390 im->sfcount[MCAST_EXCLUDE] = 1; 1391 refcount_set(&im->refcnt, 1); 1392 spin_lock_init(&im->lock); 1393 #ifdef CONFIG_IP_MULTICAST 1394 timer_setup(&im->timer, igmp_timer_expire, 0); 1395 im->unsolicit_count = net->ipv4.sysctl_igmp_qrv; 1396 #endif 1397 1398 im->next_rcu = in_dev->mc_list; 1399 in_dev->mc_count++; 1400 rcu_assign_pointer(in_dev->mc_list, im); 1401 1402 ip_mc_hash_add(in_dev, im); 1403 1404 #ifdef CONFIG_IP_MULTICAST 1405 igmpv3_del_delrec(in_dev, im); 1406 #endif 1407 igmp_group_added(im); 1408 if (!in_dev->dead) 1409 ip_rt_multicast_event(in_dev); 1410 out: 1411 return; 1412 } 1413 EXPORT_SYMBOL(ip_mc_inc_group); 1414 1415 static int ip_mc_check_iphdr(struct sk_buff *skb) 1416 { 1417 const struct iphdr *iph; 1418 unsigned int len; 1419 unsigned int offset = skb_network_offset(skb) + sizeof(*iph); 1420 1421 if (!pskb_may_pull(skb, offset)) 1422 return -EINVAL; 1423 1424 iph = ip_hdr(skb); 1425 1426 if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph)) 1427 return -EINVAL; 1428 1429 offset += ip_hdrlen(skb) - sizeof(*iph); 1430 1431 if (!pskb_may_pull(skb, offset)) 1432 return -EINVAL; 1433 1434 iph = ip_hdr(skb); 1435 1436 if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl))) 1437 return -EINVAL; 1438 1439 len = skb_network_offset(skb) + ntohs(iph->tot_len); 1440 if (skb->len < len || len < offset) 1441 return -EINVAL; 1442 1443 skb_set_transport_header(skb, offset); 1444 1445 return 0; 1446 } 1447 1448 static int ip_mc_check_igmp_reportv3(struct sk_buff *skb) 1449 { 1450 unsigned int len = skb_transport_offset(skb); 1451 1452 len += sizeof(struct igmpv3_report); 1453 1454 return pskb_may_pull(skb, len) ? 0 : -EINVAL; 1455 } 1456 1457 static int ip_mc_check_igmp_query(struct sk_buff *skb) 1458 { 1459 unsigned int len = skb_transport_offset(skb); 1460 1461 len += sizeof(struct igmphdr); 1462 if (skb->len < len) 1463 return -EINVAL; 1464 1465 /* IGMPv{1,2}? */ 1466 if (skb->len != len) { 1467 /* or IGMPv3? */ 1468 len += sizeof(struct igmpv3_query) - sizeof(struct igmphdr); 1469 if (skb->len < len || !pskb_may_pull(skb, len)) 1470 return -EINVAL; 1471 } 1472 1473 /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer 1474 * all-systems destination addresses (224.0.0.1) for general queries 1475 */ 1476 if (!igmp_hdr(skb)->group && 1477 ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP)) 1478 return -EINVAL; 1479 1480 return 0; 1481 } 1482 1483 static int ip_mc_check_igmp_msg(struct sk_buff *skb) 1484 { 1485 switch (igmp_hdr(skb)->type) { 1486 case IGMP_HOST_LEAVE_MESSAGE: 1487 case IGMP_HOST_MEMBERSHIP_REPORT: 1488 case IGMPV2_HOST_MEMBERSHIP_REPORT: 1489 /* fall through */ 1490 return 0; 1491 case IGMPV3_HOST_MEMBERSHIP_REPORT: 1492 return ip_mc_check_igmp_reportv3(skb); 1493 case IGMP_HOST_MEMBERSHIP_QUERY: 1494 return ip_mc_check_igmp_query(skb); 1495 default: 1496 return -ENOMSG; 1497 } 1498 } 1499 1500 static inline __sum16 ip_mc_validate_checksum(struct sk_buff *skb) 1501 { 1502 return skb_checksum_simple_validate(skb); 1503 } 1504 1505 static int __ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed) 1506 1507 { 1508 struct sk_buff *skb_chk; 1509 unsigned int transport_len; 1510 unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr); 1511 int ret = -EINVAL; 1512 1513 transport_len = ntohs(ip_hdr(skb)->tot_len) - ip_hdrlen(skb); 1514 1515 skb_chk = skb_checksum_trimmed(skb, transport_len, 1516 ip_mc_validate_checksum); 1517 if (!skb_chk) 1518 goto err; 1519 1520 if (!pskb_may_pull(skb_chk, len)) 1521 goto err; 1522 1523 ret = ip_mc_check_igmp_msg(skb_chk); 1524 if (ret) 1525 goto err; 1526 1527 if (skb_trimmed) 1528 *skb_trimmed = skb_chk; 1529 /* free now unneeded clone */ 1530 else if (skb_chk != skb) 1531 kfree_skb(skb_chk); 1532 1533 ret = 0; 1534 1535 err: 1536 if (ret && skb_chk && skb_chk != skb) 1537 kfree_skb(skb_chk); 1538 1539 return ret; 1540 } 1541 1542 /** 1543 * ip_mc_check_igmp - checks whether this is a sane IGMP packet 1544 * @skb: the skb to validate 1545 * @skb_trimmed: to store an skb pointer trimmed to IPv4 packet tail (optional) 1546 * 1547 * Checks whether an IPv4 packet is a valid IGMP packet. If so sets 1548 * skb transport header accordingly and returns zero. 1549 * 1550 * -EINVAL: A broken packet was detected, i.e. it violates some internet 1551 * standard 1552 * -ENOMSG: IP header validation succeeded but it is not an IGMP packet. 1553 * -ENOMEM: A memory allocation failure happened. 1554 * 1555 * Optionally, an skb pointer might be provided via skb_trimmed (or set it 1556 * to NULL): After parsing an IGMP packet successfully it will point to 1557 * an skb which has its tail aligned to the IP packet end. This might 1558 * either be the originally provided skb or a trimmed, cloned version if 1559 * the skb frame had data beyond the IP packet. A cloned skb allows us 1560 * to leave the original skb and its full frame unchanged (which might be 1561 * desirable for layer 2 frame jugglers). 1562 * 1563 * Caller needs to set the skb network header and free any returned skb if it 1564 * differs from the provided skb. 1565 */ 1566 int ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed) 1567 { 1568 int ret = ip_mc_check_iphdr(skb); 1569 1570 if (ret < 0) 1571 return ret; 1572 1573 if (ip_hdr(skb)->protocol != IPPROTO_IGMP) 1574 return -ENOMSG; 1575 1576 return __ip_mc_check_igmp(skb, skb_trimmed); 1577 } 1578 EXPORT_SYMBOL(ip_mc_check_igmp); 1579 1580 /* 1581 * Resend IGMP JOIN report; used by netdev notifier. 1582 */ 1583 static void ip_mc_rejoin_groups(struct in_device *in_dev) 1584 { 1585 #ifdef CONFIG_IP_MULTICAST 1586 struct ip_mc_list *im; 1587 int type; 1588 struct net *net = dev_net(in_dev->dev); 1589 1590 ASSERT_RTNL(); 1591 1592 for_each_pmc_rtnl(in_dev, im) { 1593 if (im->multiaddr == IGMP_ALL_HOSTS) 1594 continue; 1595 if (ipv4_is_local_multicast(im->multiaddr) && 1596 !net->ipv4.sysctl_igmp_llm_reports) 1597 continue; 1598 1599 /* a failover is happening and switches 1600 * must be notified immediately 1601 */ 1602 if (IGMP_V1_SEEN(in_dev)) 1603 type = IGMP_HOST_MEMBERSHIP_REPORT; 1604 else if (IGMP_V2_SEEN(in_dev)) 1605 type = IGMPV2_HOST_MEMBERSHIP_REPORT; 1606 else 1607 type = IGMPV3_HOST_MEMBERSHIP_REPORT; 1608 igmp_send_report(in_dev, im, type); 1609 } 1610 #endif 1611 } 1612 1613 /* 1614 * A socket has left a multicast group on device dev 1615 */ 1616 1617 void ip_mc_dec_group(struct in_device *in_dev, __be32 addr) 1618 { 1619 struct ip_mc_list *i; 1620 struct ip_mc_list __rcu **ip; 1621 1622 ASSERT_RTNL(); 1623 1624 for (ip = &in_dev->mc_list; 1625 (i = rtnl_dereference(*ip)) != NULL; 1626 ip = &i->next_rcu) { 1627 if (i->multiaddr == addr) { 1628 if (--i->users == 0) { 1629 ip_mc_hash_remove(in_dev, i); 1630 *ip = i->next_rcu; 1631 in_dev->mc_count--; 1632 igmp_group_dropped(i); 1633 ip_mc_clear_src(i); 1634 1635 if (!in_dev->dead) 1636 ip_rt_multicast_event(in_dev); 1637 1638 ip_ma_put(i); 1639 return; 1640 } 1641 break; 1642 } 1643 } 1644 } 1645 EXPORT_SYMBOL(ip_mc_dec_group); 1646 1647 /* Device changing type */ 1648 1649 void ip_mc_unmap(struct in_device *in_dev) 1650 { 1651 struct ip_mc_list *pmc; 1652 1653 ASSERT_RTNL(); 1654 1655 for_each_pmc_rtnl(in_dev, pmc) 1656 igmp_group_dropped(pmc); 1657 } 1658 1659 void ip_mc_remap(struct in_device *in_dev) 1660 { 1661 struct ip_mc_list *pmc; 1662 1663 ASSERT_RTNL(); 1664 1665 for_each_pmc_rtnl(in_dev, pmc) { 1666 #ifdef CONFIG_IP_MULTICAST 1667 igmpv3_del_delrec(in_dev, pmc); 1668 #endif 1669 igmp_group_added(pmc); 1670 } 1671 } 1672 1673 /* Device going down */ 1674 1675 void ip_mc_down(struct in_device *in_dev) 1676 { 1677 struct ip_mc_list *pmc; 1678 1679 ASSERT_RTNL(); 1680 1681 for_each_pmc_rtnl(in_dev, pmc) 1682 igmp_group_dropped(pmc); 1683 1684 #ifdef CONFIG_IP_MULTICAST 1685 in_dev->mr_ifc_count = 0; 1686 if (del_timer(&in_dev->mr_ifc_timer)) 1687 __in_dev_put(in_dev); 1688 in_dev->mr_gq_running = 0; 1689 if (del_timer(&in_dev->mr_gq_timer)) 1690 __in_dev_put(in_dev); 1691 #endif 1692 1693 ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS); 1694 } 1695 1696 void ip_mc_init_dev(struct in_device *in_dev) 1697 { 1698 #ifdef CONFIG_IP_MULTICAST 1699 struct net *net = dev_net(in_dev->dev); 1700 #endif 1701 ASSERT_RTNL(); 1702 1703 #ifdef CONFIG_IP_MULTICAST 1704 timer_setup(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 0); 1705 timer_setup(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 0); 1706 in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv; 1707 #endif 1708 1709 spin_lock_init(&in_dev->mc_tomb_lock); 1710 } 1711 1712 /* Device going up */ 1713 1714 void ip_mc_up(struct in_device *in_dev) 1715 { 1716 struct ip_mc_list *pmc; 1717 #ifdef CONFIG_IP_MULTICAST 1718 struct net *net = dev_net(in_dev->dev); 1719 #endif 1720 1721 ASSERT_RTNL(); 1722 1723 #ifdef CONFIG_IP_MULTICAST 1724 in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv; 1725 #endif 1726 ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS); 1727 1728 for_each_pmc_rtnl(in_dev, pmc) { 1729 #ifdef CONFIG_IP_MULTICAST 1730 igmpv3_del_delrec(in_dev, pmc); 1731 #endif 1732 igmp_group_added(pmc); 1733 } 1734 } 1735 1736 /* 1737 * Device is about to be destroyed: clean up. 1738 */ 1739 1740 void ip_mc_destroy_dev(struct in_device *in_dev) 1741 { 1742 struct ip_mc_list *i; 1743 1744 ASSERT_RTNL(); 1745 1746 /* Deactivate timers */ 1747 ip_mc_down(in_dev); 1748 #ifdef CONFIG_IP_MULTICAST 1749 igmpv3_clear_delrec(in_dev); 1750 #endif 1751 1752 while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) { 1753 in_dev->mc_list = i->next_rcu; 1754 in_dev->mc_count--; 1755 ip_ma_put(i); 1756 } 1757 } 1758 1759 /* RTNL is locked */ 1760 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr) 1761 { 1762 struct net_device *dev = NULL; 1763 struct in_device *idev = NULL; 1764 1765 if (imr->imr_ifindex) { 1766 idev = inetdev_by_index(net, imr->imr_ifindex); 1767 return idev; 1768 } 1769 if (imr->imr_address.s_addr) { 1770 dev = __ip_dev_find(net, imr->imr_address.s_addr, false); 1771 if (!dev) 1772 return NULL; 1773 } 1774 1775 if (!dev) { 1776 struct rtable *rt = ip_route_output(net, 1777 imr->imr_multiaddr.s_addr, 1778 0, 0, 0); 1779 if (!IS_ERR(rt)) { 1780 dev = rt->dst.dev; 1781 ip_rt_put(rt); 1782 } 1783 } 1784 if (dev) { 1785 imr->imr_ifindex = dev->ifindex; 1786 idev = __in_dev_get_rtnl(dev); 1787 } 1788 return idev; 1789 } 1790 1791 /* 1792 * Join a socket to a group 1793 */ 1794 1795 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode, 1796 __be32 *psfsrc) 1797 { 1798 struct ip_sf_list *psf, *psf_prev; 1799 int rv = 0; 1800 1801 psf_prev = NULL; 1802 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1803 if (psf->sf_inaddr == *psfsrc) 1804 break; 1805 psf_prev = psf; 1806 } 1807 if (!psf || psf->sf_count[sfmode] == 0) { 1808 /* source filter not found, or count wrong => bug */ 1809 return -ESRCH; 1810 } 1811 psf->sf_count[sfmode]--; 1812 if (psf->sf_count[sfmode] == 0) { 1813 ip_rt_multicast_event(pmc->interface); 1814 } 1815 if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) { 1816 #ifdef CONFIG_IP_MULTICAST 1817 struct in_device *in_dev = pmc->interface; 1818 struct net *net = dev_net(in_dev->dev); 1819 #endif 1820 1821 /* no more filters for this source */ 1822 if (psf_prev) 1823 psf_prev->sf_next = psf->sf_next; 1824 else 1825 pmc->sources = psf->sf_next; 1826 #ifdef CONFIG_IP_MULTICAST 1827 if (psf->sf_oldin && 1828 !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) { 1829 psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1830 psf->sf_next = pmc->tomb; 1831 pmc->tomb = psf; 1832 rv = 1; 1833 } else 1834 #endif 1835 kfree(psf); 1836 } 1837 return rv; 1838 } 1839 1840 #ifndef CONFIG_IP_MULTICAST 1841 #define igmp_ifc_event(x) do { } while (0) 1842 #endif 1843 1844 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 1845 int sfcount, __be32 *psfsrc, int delta) 1846 { 1847 struct ip_mc_list *pmc; 1848 int changerec = 0; 1849 int i, err; 1850 1851 if (!in_dev) 1852 return -ENODEV; 1853 rcu_read_lock(); 1854 for_each_pmc_rcu(in_dev, pmc) { 1855 if (*pmca == pmc->multiaddr) 1856 break; 1857 } 1858 if (!pmc) { 1859 /* MCA not found?? bug */ 1860 rcu_read_unlock(); 1861 return -ESRCH; 1862 } 1863 spin_lock_bh(&pmc->lock); 1864 rcu_read_unlock(); 1865 #ifdef CONFIG_IP_MULTICAST 1866 sf_markstate(pmc); 1867 #endif 1868 if (!delta) { 1869 err = -EINVAL; 1870 if (!pmc->sfcount[sfmode]) 1871 goto out_unlock; 1872 pmc->sfcount[sfmode]--; 1873 } 1874 err = 0; 1875 for (i = 0; i < sfcount; i++) { 1876 int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]); 1877 1878 changerec |= rv > 0; 1879 if (!err && rv < 0) 1880 err = rv; 1881 } 1882 if (pmc->sfmode == MCAST_EXCLUDE && 1883 pmc->sfcount[MCAST_EXCLUDE] == 0 && 1884 pmc->sfcount[MCAST_INCLUDE]) { 1885 #ifdef CONFIG_IP_MULTICAST 1886 struct ip_sf_list *psf; 1887 struct net *net = dev_net(in_dev->dev); 1888 #endif 1889 1890 /* filter mode change */ 1891 pmc->sfmode = MCAST_INCLUDE; 1892 #ifdef CONFIG_IP_MULTICAST 1893 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1894 in_dev->mr_ifc_count = pmc->crcount; 1895 for (psf = pmc->sources; psf; psf = psf->sf_next) 1896 psf->sf_crcount = 0; 1897 igmp_ifc_event(pmc->interface); 1898 } else if (sf_setstate(pmc) || changerec) { 1899 igmp_ifc_event(pmc->interface); 1900 #endif 1901 } 1902 out_unlock: 1903 spin_unlock_bh(&pmc->lock); 1904 return err; 1905 } 1906 1907 /* 1908 * Add multicast single-source filter to the interface list 1909 */ 1910 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode, 1911 __be32 *psfsrc) 1912 { 1913 struct ip_sf_list *psf, *psf_prev; 1914 1915 psf_prev = NULL; 1916 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1917 if (psf->sf_inaddr == *psfsrc) 1918 break; 1919 psf_prev = psf; 1920 } 1921 if (!psf) { 1922 psf = kzalloc(sizeof(*psf), GFP_ATOMIC); 1923 if (!psf) 1924 return -ENOBUFS; 1925 psf->sf_inaddr = *psfsrc; 1926 if (psf_prev) { 1927 psf_prev->sf_next = psf; 1928 } else 1929 pmc->sources = psf; 1930 } 1931 psf->sf_count[sfmode]++; 1932 if (psf->sf_count[sfmode] == 1) { 1933 ip_rt_multicast_event(pmc->interface); 1934 } 1935 return 0; 1936 } 1937 1938 #ifdef CONFIG_IP_MULTICAST 1939 static void sf_markstate(struct ip_mc_list *pmc) 1940 { 1941 struct ip_sf_list *psf; 1942 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; 1943 1944 for (psf = pmc->sources; psf; psf = psf->sf_next) 1945 if (pmc->sfcount[MCAST_EXCLUDE]) { 1946 psf->sf_oldin = mca_xcount == 1947 psf->sf_count[MCAST_EXCLUDE] && 1948 !psf->sf_count[MCAST_INCLUDE]; 1949 } else 1950 psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0; 1951 } 1952 1953 static int sf_setstate(struct ip_mc_list *pmc) 1954 { 1955 struct ip_sf_list *psf, *dpsf; 1956 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; 1957 int qrv = pmc->interface->mr_qrv; 1958 int new_in, rv; 1959 1960 rv = 0; 1961 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1962 if (pmc->sfcount[MCAST_EXCLUDE]) { 1963 new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] && 1964 !psf->sf_count[MCAST_INCLUDE]; 1965 } else 1966 new_in = psf->sf_count[MCAST_INCLUDE] != 0; 1967 if (new_in) { 1968 if (!psf->sf_oldin) { 1969 struct ip_sf_list *prev = NULL; 1970 1971 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) { 1972 if (dpsf->sf_inaddr == psf->sf_inaddr) 1973 break; 1974 prev = dpsf; 1975 } 1976 if (dpsf) { 1977 if (prev) 1978 prev->sf_next = dpsf->sf_next; 1979 else 1980 pmc->tomb = dpsf->sf_next; 1981 kfree(dpsf); 1982 } 1983 psf->sf_crcount = qrv; 1984 rv++; 1985 } 1986 } else if (psf->sf_oldin) { 1987 1988 psf->sf_crcount = 0; 1989 /* 1990 * add or update "delete" records if an active filter 1991 * is now inactive 1992 */ 1993 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) 1994 if (dpsf->sf_inaddr == psf->sf_inaddr) 1995 break; 1996 if (!dpsf) { 1997 dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC); 1998 if (!dpsf) 1999 continue; 2000 *dpsf = *psf; 2001 /* pmc->lock held by callers */ 2002 dpsf->sf_next = pmc->tomb; 2003 pmc->tomb = dpsf; 2004 } 2005 dpsf->sf_crcount = qrv; 2006 rv++; 2007 } 2008 } 2009 return rv; 2010 } 2011 #endif 2012 2013 /* 2014 * Add multicast source filter list to the interface list 2015 */ 2016 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 2017 int sfcount, __be32 *psfsrc, int delta) 2018 { 2019 struct ip_mc_list *pmc; 2020 int isexclude; 2021 int i, err; 2022 2023 if (!in_dev) 2024 return -ENODEV; 2025 rcu_read_lock(); 2026 for_each_pmc_rcu(in_dev, pmc) { 2027 if (*pmca == pmc->multiaddr) 2028 break; 2029 } 2030 if (!pmc) { 2031 /* MCA not found?? bug */ 2032 rcu_read_unlock(); 2033 return -ESRCH; 2034 } 2035 spin_lock_bh(&pmc->lock); 2036 rcu_read_unlock(); 2037 2038 #ifdef CONFIG_IP_MULTICAST 2039 sf_markstate(pmc); 2040 #endif 2041 isexclude = pmc->sfmode == MCAST_EXCLUDE; 2042 if (!delta) 2043 pmc->sfcount[sfmode]++; 2044 err = 0; 2045 for (i = 0; i < sfcount; i++) { 2046 err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]); 2047 if (err) 2048 break; 2049 } 2050 if (err) { 2051 int j; 2052 2053 if (!delta) 2054 pmc->sfcount[sfmode]--; 2055 for (j = 0; j < i; j++) 2056 (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]); 2057 } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) { 2058 #ifdef CONFIG_IP_MULTICAST 2059 struct ip_sf_list *psf; 2060 struct net *net = dev_net(pmc->interface->dev); 2061 in_dev = pmc->interface; 2062 #endif 2063 2064 /* filter mode change */ 2065 if (pmc->sfcount[MCAST_EXCLUDE]) 2066 pmc->sfmode = MCAST_EXCLUDE; 2067 else if (pmc->sfcount[MCAST_INCLUDE]) 2068 pmc->sfmode = MCAST_INCLUDE; 2069 #ifdef CONFIG_IP_MULTICAST 2070 /* else no filters; keep old mode for reports */ 2071 2072 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 2073 in_dev->mr_ifc_count = pmc->crcount; 2074 for (psf = pmc->sources; psf; psf = psf->sf_next) 2075 psf->sf_crcount = 0; 2076 igmp_ifc_event(in_dev); 2077 } else if (sf_setstate(pmc)) { 2078 igmp_ifc_event(in_dev); 2079 #endif 2080 } 2081 spin_unlock_bh(&pmc->lock); 2082 return err; 2083 } 2084 2085 static void ip_mc_clear_src(struct ip_mc_list *pmc) 2086 { 2087 struct ip_sf_list *psf, *nextpsf, *tomb, *sources; 2088 2089 spin_lock_bh(&pmc->lock); 2090 tomb = pmc->tomb; 2091 pmc->tomb = NULL; 2092 sources = pmc->sources; 2093 pmc->sources = NULL; 2094 pmc->sfmode = MCAST_EXCLUDE; 2095 pmc->sfcount[MCAST_INCLUDE] = 0; 2096 pmc->sfcount[MCAST_EXCLUDE] = 1; 2097 spin_unlock_bh(&pmc->lock); 2098 2099 for (psf = tomb; psf; psf = nextpsf) { 2100 nextpsf = psf->sf_next; 2101 kfree(psf); 2102 } 2103 for (psf = sources; psf; psf = nextpsf) { 2104 nextpsf = psf->sf_next; 2105 kfree(psf); 2106 } 2107 } 2108 2109 /* Join a multicast group 2110 */ 2111 2112 int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr) 2113 { 2114 __be32 addr = imr->imr_multiaddr.s_addr; 2115 struct ip_mc_socklist *iml, *i; 2116 struct in_device *in_dev; 2117 struct inet_sock *inet = inet_sk(sk); 2118 struct net *net = sock_net(sk); 2119 int ifindex; 2120 int count = 0; 2121 int err; 2122 2123 ASSERT_RTNL(); 2124 2125 if (!ipv4_is_multicast(addr)) 2126 return -EINVAL; 2127 2128 in_dev = ip_mc_find_dev(net, imr); 2129 2130 if (!in_dev) { 2131 err = -ENODEV; 2132 goto done; 2133 } 2134 2135 err = -EADDRINUSE; 2136 ifindex = imr->imr_ifindex; 2137 for_each_pmc_rtnl(inet, i) { 2138 if (i->multi.imr_multiaddr.s_addr == addr && 2139 i->multi.imr_ifindex == ifindex) 2140 goto done; 2141 count++; 2142 } 2143 err = -ENOBUFS; 2144 if (count >= net->ipv4.sysctl_igmp_max_memberships) 2145 goto done; 2146 iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL); 2147 if (!iml) 2148 goto done; 2149 2150 memcpy(&iml->multi, imr, sizeof(*imr)); 2151 iml->next_rcu = inet->mc_list; 2152 iml->sflist = NULL; 2153 iml->sfmode = MCAST_EXCLUDE; 2154 rcu_assign_pointer(inet->mc_list, iml); 2155 ip_mc_inc_group(in_dev, addr); 2156 err = 0; 2157 done: 2158 return err; 2159 } 2160 EXPORT_SYMBOL(ip_mc_join_group); 2161 2162 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml, 2163 struct in_device *in_dev) 2164 { 2165 struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist); 2166 int err; 2167 2168 if (!psf) { 2169 /* any-source empty exclude case */ 2170 return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, 2171 iml->sfmode, 0, NULL, 0); 2172 } 2173 err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, 2174 iml->sfmode, psf->sl_count, psf->sl_addr, 0); 2175 RCU_INIT_POINTER(iml->sflist, NULL); 2176 /* decrease mem now to avoid the memleak warning */ 2177 atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc); 2178 kfree_rcu(psf, rcu); 2179 return err; 2180 } 2181 2182 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr) 2183 { 2184 struct inet_sock *inet = inet_sk(sk); 2185 struct ip_mc_socklist *iml; 2186 struct ip_mc_socklist __rcu **imlp; 2187 struct in_device *in_dev; 2188 struct net *net = sock_net(sk); 2189 __be32 group = imr->imr_multiaddr.s_addr; 2190 u32 ifindex; 2191 int ret = -EADDRNOTAVAIL; 2192 2193 ASSERT_RTNL(); 2194 2195 in_dev = ip_mc_find_dev(net, imr); 2196 if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) { 2197 ret = -ENODEV; 2198 goto out; 2199 } 2200 ifindex = imr->imr_ifindex; 2201 for (imlp = &inet->mc_list; 2202 (iml = rtnl_dereference(*imlp)) != NULL; 2203 imlp = &iml->next_rcu) { 2204 if (iml->multi.imr_multiaddr.s_addr != group) 2205 continue; 2206 if (ifindex) { 2207 if (iml->multi.imr_ifindex != ifindex) 2208 continue; 2209 } else if (imr->imr_address.s_addr && imr->imr_address.s_addr != 2210 iml->multi.imr_address.s_addr) 2211 continue; 2212 2213 (void) ip_mc_leave_src(sk, iml, in_dev); 2214 2215 *imlp = iml->next_rcu; 2216 2217 if (in_dev) 2218 ip_mc_dec_group(in_dev, group); 2219 2220 /* decrease mem now to avoid the memleak warning */ 2221 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); 2222 kfree_rcu(iml, rcu); 2223 return 0; 2224 } 2225 out: 2226 return ret; 2227 } 2228 EXPORT_SYMBOL(ip_mc_leave_group); 2229 2230 int ip_mc_source(int add, int omode, struct sock *sk, struct 2231 ip_mreq_source *mreqs, int ifindex) 2232 { 2233 int err; 2234 struct ip_mreqn imr; 2235 __be32 addr = mreqs->imr_multiaddr; 2236 struct ip_mc_socklist *pmc; 2237 struct in_device *in_dev = NULL; 2238 struct inet_sock *inet = inet_sk(sk); 2239 struct ip_sf_socklist *psl; 2240 struct net *net = sock_net(sk); 2241 int leavegroup = 0; 2242 int i, j, rv; 2243 2244 if (!ipv4_is_multicast(addr)) 2245 return -EINVAL; 2246 2247 ASSERT_RTNL(); 2248 2249 imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr; 2250 imr.imr_address.s_addr = mreqs->imr_interface; 2251 imr.imr_ifindex = ifindex; 2252 in_dev = ip_mc_find_dev(net, &imr); 2253 2254 if (!in_dev) { 2255 err = -ENODEV; 2256 goto done; 2257 } 2258 err = -EADDRNOTAVAIL; 2259 2260 for_each_pmc_rtnl(inet, pmc) { 2261 if ((pmc->multi.imr_multiaddr.s_addr == 2262 imr.imr_multiaddr.s_addr) && 2263 (pmc->multi.imr_ifindex == imr.imr_ifindex)) 2264 break; 2265 } 2266 if (!pmc) { /* must have a prior join */ 2267 err = -EINVAL; 2268 goto done; 2269 } 2270 /* if a source filter was set, must be the same mode as before */ 2271 if (pmc->sflist) { 2272 if (pmc->sfmode != omode) { 2273 err = -EINVAL; 2274 goto done; 2275 } 2276 } else if (pmc->sfmode != omode) { 2277 /* allow mode switches for empty-set filters */ 2278 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0); 2279 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0, 2280 NULL, 0); 2281 pmc->sfmode = omode; 2282 } 2283 2284 psl = rtnl_dereference(pmc->sflist); 2285 if (!add) { 2286 if (!psl) 2287 goto done; /* err = -EADDRNOTAVAIL */ 2288 rv = !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) /* source not found */ 2296 goto done; /* err = -EADDRNOTAVAIL */ 2297 2298 /* special case - (INCLUDE, empty) == LEAVE_GROUP */ 2299 if (psl->sl_count == 1 && omode == MCAST_INCLUDE) { 2300 leavegroup = 1; 2301 goto done; 2302 } 2303 2304 /* update the interface filter */ 2305 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1, 2306 &mreqs->imr_sourceaddr, 1); 2307 2308 for (j = i+1; j < psl->sl_count; j++) 2309 psl->sl_addr[j-1] = psl->sl_addr[j]; 2310 psl->sl_count--; 2311 err = 0; 2312 goto done; 2313 } 2314 /* else, add a new source to the filter */ 2315 2316 if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) { 2317 err = -ENOBUFS; 2318 goto done; 2319 } 2320 if (!psl || psl->sl_count == psl->sl_max) { 2321 struct ip_sf_socklist *newpsl; 2322 int count = IP_SFBLOCK; 2323 2324 if (psl) 2325 count += psl->sl_max; 2326 newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL); 2327 if (!newpsl) { 2328 err = -ENOBUFS; 2329 goto done; 2330 } 2331 newpsl->sl_max = count; 2332 newpsl->sl_count = count - IP_SFBLOCK; 2333 if (psl) { 2334 for (i = 0; i < psl->sl_count; i++) 2335 newpsl->sl_addr[i] = psl->sl_addr[i]; 2336 /* decrease mem now to avoid the memleak warning */ 2337 atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc); 2338 kfree_rcu(psl, rcu); 2339 } 2340 rcu_assign_pointer(pmc->sflist, newpsl); 2341 psl = newpsl; 2342 } 2343 rv = 1; /* > 0 for insert logic below if sl_count is 0 */ 2344 for (i = 0; i < psl->sl_count; i++) { 2345 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr, 2346 sizeof(__be32)); 2347 if (rv == 0) 2348 break; 2349 } 2350 if (rv == 0) /* address already there is an error */ 2351 goto done; 2352 for (j = psl->sl_count-1; j >= i; j--) 2353 psl->sl_addr[j+1] = psl->sl_addr[j]; 2354 psl->sl_addr[i] = mreqs->imr_sourceaddr; 2355 psl->sl_count++; 2356 err = 0; 2357 /* update the interface list */ 2358 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1, 2359 &mreqs->imr_sourceaddr, 1); 2360 done: 2361 if (leavegroup) 2362 err = ip_mc_leave_group(sk, &imr); 2363 return err; 2364 } 2365 2366 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex) 2367 { 2368 int err = 0; 2369 struct ip_mreqn imr; 2370 __be32 addr = msf->imsf_multiaddr; 2371 struct ip_mc_socklist *pmc; 2372 struct in_device *in_dev; 2373 struct inet_sock *inet = inet_sk(sk); 2374 struct ip_sf_socklist *newpsl, *psl; 2375 struct net *net = sock_net(sk); 2376 int leavegroup = 0; 2377 2378 if (!ipv4_is_multicast(addr)) 2379 return -EINVAL; 2380 if (msf->imsf_fmode != MCAST_INCLUDE && 2381 msf->imsf_fmode != MCAST_EXCLUDE) 2382 return -EINVAL; 2383 2384 ASSERT_RTNL(); 2385 2386 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; 2387 imr.imr_address.s_addr = msf->imsf_interface; 2388 imr.imr_ifindex = ifindex; 2389 in_dev = ip_mc_find_dev(net, &imr); 2390 2391 if (!in_dev) { 2392 err = -ENODEV; 2393 goto done; 2394 } 2395 2396 /* special case - (INCLUDE, empty) == LEAVE_GROUP */ 2397 if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) { 2398 leavegroup = 1; 2399 goto done; 2400 } 2401 2402 for_each_pmc_rtnl(inet, pmc) { 2403 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && 2404 pmc->multi.imr_ifindex == imr.imr_ifindex) 2405 break; 2406 } 2407 if (!pmc) { /* must have a prior join */ 2408 err = -EINVAL; 2409 goto done; 2410 } 2411 if (msf->imsf_numsrc) { 2412 newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc), 2413 GFP_KERNEL); 2414 if (!newpsl) { 2415 err = -ENOBUFS; 2416 goto done; 2417 } 2418 newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc; 2419 memcpy(newpsl->sl_addr, msf->imsf_slist, 2420 msf->imsf_numsrc * sizeof(msf->imsf_slist[0])); 2421 err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr, 2422 msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0); 2423 if (err) { 2424 sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max)); 2425 goto done; 2426 } 2427 } else { 2428 newpsl = NULL; 2429 (void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr, 2430 msf->imsf_fmode, 0, NULL, 0); 2431 } 2432 psl = rtnl_dereference(pmc->sflist); 2433 if (psl) { 2434 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, 2435 psl->sl_count, psl->sl_addr, 0); 2436 /* decrease mem now to avoid the memleak warning */ 2437 atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc); 2438 kfree_rcu(psl, rcu); 2439 } else 2440 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, 2441 0, NULL, 0); 2442 rcu_assign_pointer(pmc->sflist, newpsl); 2443 pmc->sfmode = msf->imsf_fmode; 2444 err = 0; 2445 done: 2446 if (leavegroup) 2447 err = ip_mc_leave_group(sk, &imr); 2448 return err; 2449 } 2450 2451 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf, 2452 struct ip_msfilter __user *optval, int __user *optlen) 2453 { 2454 int err, len, count, copycount; 2455 struct ip_mreqn imr; 2456 __be32 addr = msf->imsf_multiaddr; 2457 struct ip_mc_socklist *pmc; 2458 struct in_device *in_dev; 2459 struct inet_sock *inet = inet_sk(sk); 2460 struct ip_sf_socklist *psl; 2461 struct net *net = sock_net(sk); 2462 2463 ASSERT_RTNL(); 2464 2465 if (!ipv4_is_multicast(addr)) 2466 return -EINVAL; 2467 2468 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; 2469 imr.imr_address.s_addr = msf->imsf_interface; 2470 imr.imr_ifindex = 0; 2471 in_dev = ip_mc_find_dev(net, &imr); 2472 2473 if (!in_dev) { 2474 err = -ENODEV; 2475 goto done; 2476 } 2477 err = -EADDRNOTAVAIL; 2478 2479 for_each_pmc_rtnl(inet, pmc) { 2480 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && 2481 pmc->multi.imr_ifindex == imr.imr_ifindex) 2482 break; 2483 } 2484 if (!pmc) /* must have a prior join */ 2485 goto done; 2486 msf->imsf_fmode = pmc->sfmode; 2487 psl = rtnl_dereference(pmc->sflist); 2488 if (!psl) { 2489 len = 0; 2490 count = 0; 2491 } else { 2492 count = psl->sl_count; 2493 } 2494 copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc; 2495 len = copycount * sizeof(psl->sl_addr[0]); 2496 msf->imsf_numsrc = count; 2497 if (put_user(IP_MSFILTER_SIZE(copycount), optlen) || 2498 copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) { 2499 return -EFAULT; 2500 } 2501 if (len && 2502 copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len)) 2503 return -EFAULT; 2504 return 0; 2505 done: 2506 return err; 2507 } 2508 2509 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf, 2510 struct group_filter __user *optval, int __user *optlen) 2511 { 2512 int err, i, count, copycount; 2513 struct sockaddr_in *psin; 2514 __be32 addr; 2515 struct ip_mc_socklist *pmc; 2516 struct inet_sock *inet = inet_sk(sk); 2517 struct ip_sf_socklist *psl; 2518 2519 ASSERT_RTNL(); 2520 2521 psin = (struct sockaddr_in *)&gsf->gf_group; 2522 if (psin->sin_family != AF_INET) 2523 return -EINVAL; 2524 addr = psin->sin_addr.s_addr; 2525 if (!ipv4_is_multicast(addr)) 2526 return -EINVAL; 2527 2528 err = -EADDRNOTAVAIL; 2529 2530 for_each_pmc_rtnl(inet, pmc) { 2531 if (pmc->multi.imr_multiaddr.s_addr == addr && 2532 pmc->multi.imr_ifindex == gsf->gf_interface) 2533 break; 2534 } 2535 if (!pmc) /* must have a prior join */ 2536 goto done; 2537 gsf->gf_fmode = pmc->sfmode; 2538 psl = rtnl_dereference(pmc->sflist); 2539 count = psl ? psl->sl_count : 0; 2540 copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc; 2541 gsf->gf_numsrc = count; 2542 if (put_user(GROUP_FILTER_SIZE(copycount), optlen) || 2543 copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) { 2544 return -EFAULT; 2545 } 2546 for (i = 0; i < copycount; i++) { 2547 struct sockaddr_storage ss; 2548 2549 psin = (struct sockaddr_in *)&ss; 2550 memset(&ss, 0, sizeof(ss)); 2551 psin->sin_family = AF_INET; 2552 psin->sin_addr.s_addr = psl->sl_addr[i]; 2553 if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss))) 2554 return -EFAULT; 2555 } 2556 return 0; 2557 done: 2558 return err; 2559 } 2560 2561 /* 2562 * check if a multicast source filter allows delivery for a given <src,dst,intf> 2563 */ 2564 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, 2565 int dif, int sdif) 2566 { 2567 struct inet_sock *inet = inet_sk(sk); 2568 struct ip_mc_socklist *pmc; 2569 struct ip_sf_socklist *psl; 2570 int i; 2571 int ret; 2572 2573 ret = 1; 2574 if (!ipv4_is_multicast(loc_addr)) 2575 goto out; 2576 2577 rcu_read_lock(); 2578 for_each_pmc_rcu(inet, pmc) { 2579 if (pmc->multi.imr_multiaddr.s_addr == loc_addr && 2580 (pmc->multi.imr_ifindex == dif || 2581 (sdif && pmc->multi.imr_ifindex == sdif))) 2582 break; 2583 } 2584 ret = inet->mc_all; 2585 if (!pmc) 2586 goto unlock; 2587 psl = rcu_dereference(pmc->sflist); 2588 ret = (pmc->sfmode == MCAST_EXCLUDE); 2589 if (!psl) 2590 goto unlock; 2591 2592 for (i = 0; i < psl->sl_count; i++) { 2593 if (psl->sl_addr[i] == rmt_addr) 2594 break; 2595 } 2596 ret = 0; 2597 if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count) 2598 goto unlock; 2599 if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count) 2600 goto unlock; 2601 ret = 1; 2602 unlock: 2603 rcu_read_unlock(); 2604 out: 2605 return ret; 2606 } 2607 2608 /* 2609 * A socket is closing. 2610 */ 2611 2612 void ip_mc_drop_socket(struct sock *sk) 2613 { 2614 struct inet_sock *inet = inet_sk(sk); 2615 struct ip_mc_socklist *iml; 2616 struct net *net = sock_net(sk); 2617 2618 if (!inet->mc_list) 2619 return; 2620 2621 rtnl_lock(); 2622 while ((iml = rtnl_dereference(inet->mc_list)) != NULL) { 2623 struct in_device *in_dev; 2624 2625 inet->mc_list = iml->next_rcu; 2626 in_dev = inetdev_by_index(net, iml->multi.imr_ifindex); 2627 (void) ip_mc_leave_src(sk, iml, in_dev); 2628 if (in_dev) 2629 ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr); 2630 /* decrease mem now to avoid the memleak warning */ 2631 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); 2632 kfree_rcu(iml, rcu); 2633 } 2634 rtnl_unlock(); 2635 } 2636 2637 /* called with rcu_read_lock() */ 2638 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto) 2639 { 2640 struct ip_mc_list *im; 2641 struct ip_mc_list __rcu **mc_hash; 2642 struct ip_sf_list *psf; 2643 int rv = 0; 2644 2645 mc_hash = rcu_dereference(in_dev->mc_hash); 2646 if (mc_hash) { 2647 u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG); 2648 2649 for (im = rcu_dereference(mc_hash[hash]); 2650 im != NULL; 2651 im = rcu_dereference(im->next_hash)) { 2652 if (im->multiaddr == mc_addr) 2653 break; 2654 } 2655 } else { 2656 for_each_pmc_rcu(in_dev, im) { 2657 if (im->multiaddr == mc_addr) 2658 break; 2659 } 2660 } 2661 if (im && proto == IPPROTO_IGMP) { 2662 rv = 1; 2663 } else if (im) { 2664 if (src_addr) { 2665 for (psf = im->sources; psf; psf = psf->sf_next) { 2666 if (psf->sf_inaddr == src_addr) 2667 break; 2668 } 2669 if (psf) 2670 rv = psf->sf_count[MCAST_INCLUDE] || 2671 psf->sf_count[MCAST_EXCLUDE] != 2672 im->sfcount[MCAST_EXCLUDE]; 2673 else 2674 rv = im->sfcount[MCAST_EXCLUDE] != 0; 2675 } else 2676 rv = 1; /* unspecified source; tentatively allow */ 2677 } 2678 return rv; 2679 } 2680 2681 #if defined(CONFIG_PROC_FS) 2682 struct igmp_mc_iter_state { 2683 struct seq_net_private p; 2684 struct net_device *dev; 2685 struct in_device *in_dev; 2686 }; 2687 2688 #define igmp_mc_seq_private(seq) ((struct igmp_mc_iter_state *)(seq)->private) 2689 2690 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq) 2691 { 2692 struct net *net = seq_file_net(seq); 2693 struct ip_mc_list *im = NULL; 2694 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2695 2696 state->in_dev = NULL; 2697 for_each_netdev_rcu(net, state->dev) { 2698 struct in_device *in_dev; 2699 2700 in_dev = __in_dev_get_rcu(state->dev); 2701 if (!in_dev) 2702 continue; 2703 im = rcu_dereference(in_dev->mc_list); 2704 if (im) { 2705 state->in_dev = in_dev; 2706 break; 2707 } 2708 } 2709 return im; 2710 } 2711 2712 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im) 2713 { 2714 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2715 2716 im = rcu_dereference(im->next_rcu); 2717 while (!im) { 2718 state->dev = next_net_device_rcu(state->dev); 2719 if (!state->dev) { 2720 state->in_dev = NULL; 2721 break; 2722 } 2723 state->in_dev = __in_dev_get_rcu(state->dev); 2724 if (!state->in_dev) 2725 continue; 2726 im = rcu_dereference(state->in_dev->mc_list); 2727 } 2728 return im; 2729 } 2730 2731 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos) 2732 { 2733 struct ip_mc_list *im = igmp_mc_get_first(seq); 2734 if (im) 2735 while (pos && (im = igmp_mc_get_next(seq, im)) != NULL) 2736 --pos; 2737 return pos ? NULL : im; 2738 } 2739 2740 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos) 2741 __acquires(rcu) 2742 { 2743 rcu_read_lock(); 2744 return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 2745 } 2746 2747 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2748 { 2749 struct ip_mc_list *im; 2750 if (v == SEQ_START_TOKEN) 2751 im = igmp_mc_get_first(seq); 2752 else 2753 im = igmp_mc_get_next(seq, v); 2754 ++*pos; 2755 return im; 2756 } 2757 2758 static void igmp_mc_seq_stop(struct seq_file *seq, void *v) 2759 __releases(rcu) 2760 { 2761 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2762 2763 state->in_dev = NULL; 2764 state->dev = NULL; 2765 rcu_read_unlock(); 2766 } 2767 2768 static int igmp_mc_seq_show(struct seq_file *seq, void *v) 2769 { 2770 if (v == SEQ_START_TOKEN) 2771 seq_puts(seq, 2772 "Idx\tDevice : Count Querier\tGroup Users Timer\tReporter\n"); 2773 else { 2774 struct ip_mc_list *im = (struct ip_mc_list *)v; 2775 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2776 char *querier; 2777 long delta; 2778 2779 #ifdef CONFIG_IP_MULTICAST 2780 querier = IGMP_V1_SEEN(state->in_dev) ? "V1" : 2781 IGMP_V2_SEEN(state->in_dev) ? "V2" : 2782 "V3"; 2783 #else 2784 querier = "NONE"; 2785 #endif 2786 2787 if (rcu_access_pointer(state->in_dev->mc_list) == im) { 2788 seq_printf(seq, "%d\t%-10s: %5d %7s\n", 2789 state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier); 2790 } 2791 2792 delta = im->timer.expires - jiffies; 2793 seq_printf(seq, 2794 "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n", 2795 im->multiaddr, im->users, 2796 im->tm_running, 2797 im->tm_running ? jiffies_delta_to_clock_t(delta) : 0, 2798 im->reporter); 2799 } 2800 return 0; 2801 } 2802 2803 static const struct seq_operations igmp_mc_seq_ops = { 2804 .start = igmp_mc_seq_start, 2805 .next = igmp_mc_seq_next, 2806 .stop = igmp_mc_seq_stop, 2807 .show = igmp_mc_seq_show, 2808 }; 2809 2810 static int igmp_mc_seq_open(struct inode *inode, struct file *file) 2811 { 2812 return seq_open_net(inode, file, &igmp_mc_seq_ops, 2813 sizeof(struct igmp_mc_iter_state)); 2814 } 2815 2816 static const struct file_operations igmp_mc_seq_fops = { 2817 .owner = THIS_MODULE, 2818 .open = igmp_mc_seq_open, 2819 .read = seq_read, 2820 .llseek = seq_lseek, 2821 .release = seq_release_net, 2822 }; 2823 2824 struct igmp_mcf_iter_state { 2825 struct seq_net_private p; 2826 struct net_device *dev; 2827 struct in_device *idev; 2828 struct ip_mc_list *im; 2829 }; 2830 2831 #define igmp_mcf_seq_private(seq) ((struct igmp_mcf_iter_state *)(seq)->private) 2832 2833 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq) 2834 { 2835 struct net *net = seq_file_net(seq); 2836 struct ip_sf_list *psf = NULL; 2837 struct ip_mc_list *im = NULL; 2838 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2839 2840 state->idev = NULL; 2841 state->im = NULL; 2842 for_each_netdev_rcu(net, state->dev) { 2843 struct in_device *idev; 2844 idev = __in_dev_get_rcu(state->dev); 2845 if (unlikely(!idev)) 2846 continue; 2847 im = rcu_dereference(idev->mc_list); 2848 if (likely(im)) { 2849 spin_lock_bh(&im->lock); 2850 psf = im->sources; 2851 if (likely(psf)) { 2852 state->im = im; 2853 state->idev = idev; 2854 break; 2855 } 2856 spin_unlock_bh(&im->lock); 2857 } 2858 } 2859 return psf; 2860 } 2861 2862 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf) 2863 { 2864 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2865 2866 psf = psf->sf_next; 2867 while (!psf) { 2868 spin_unlock_bh(&state->im->lock); 2869 state->im = state->im->next; 2870 while (!state->im) { 2871 state->dev = next_net_device_rcu(state->dev); 2872 if (!state->dev) { 2873 state->idev = NULL; 2874 goto out; 2875 } 2876 state->idev = __in_dev_get_rcu(state->dev); 2877 if (!state->idev) 2878 continue; 2879 state->im = rcu_dereference(state->idev->mc_list); 2880 } 2881 if (!state->im) 2882 break; 2883 spin_lock_bh(&state->im->lock); 2884 psf = state->im->sources; 2885 } 2886 out: 2887 return psf; 2888 } 2889 2890 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos) 2891 { 2892 struct ip_sf_list *psf = igmp_mcf_get_first(seq); 2893 if (psf) 2894 while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL) 2895 --pos; 2896 return pos ? NULL : psf; 2897 } 2898 2899 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos) 2900 __acquires(rcu) 2901 { 2902 rcu_read_lock(); 2903 return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 2904 } 2905 2906 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2907 { 2908 struct ip_sf_list *psf; 2909 if (v == SEQ_START_TOKEN) 2910 psf = igmp_mcf_get_first(seq); 2911 else 2912 psf = igmp_mcf_get_next(seq, v); 2913 ++*pos; 2914 return psf; 2915 } 2916 2917 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v) 2918 __releases(rcu) 2919 { 2920 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2921 if (likely(state->im)) { 2922 spin_unlock_bh(&state->im->lock); 2923 state->im = NULL; 2924 } 2925 state->idev = NULL; 2926 state->dev = NULL; 2927 rcu_read_unlock(); 2928 } 2929 2930 static int igmp_mcf_seq_show(struct seq_file *seq, void *v) 2931 { 2932 struct ip_sf_list *psf = (struct ip_sf_list *)v; 2933 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2934 2935 if (v == SEQ_START_TOKEN) { 2936 seq_puts(seq, "Idx Device MCA SRC INC EXC\n"); 2937 } else { 2938 seq_printf(seq, 2939 "%3d %6.6s 0x%08x " 2940 "0x%08x %6lu %6lu\n", 2941 state->dev->ifindex, state->dev->name, 2942 ntohl(state->im->multiaddr), 2943 ntohl(psf->sf_inaddr), 2944 psf->sf_count[MCAST_INCLUDE], 2945 psf->sf_count[MCAST_EXCLUDE]); 2946 } 2947 return 0; 2948 } 2949 2950 static const struct seq_operations igmp_mcf_seq_ops = { 2951 .start = igmp_mcf_seq_start, 2952 .next = igmp_mcf_seq_next, 2953 .stop = igmp_mcf_seq_stop, 2954 .show = igmp_mcf_seq_show, 2955 }; 2956 2957 static int igmp_mcf_seq_open(struct inode *inode, struct file *file) 2958 { 2959 return seq_open_net(inode, file, &igmp_mcf_seq_ops, 2960 sizeof(struct igmp_mcf_iter_state)); 2961 } 2962 2963 static const struct file_operations igmp_mcf_seq_fops = { 2964 .owner = THIS_MODULE, 2965 .open = igmp_mcf_seq_open, 2966 .read = seq_read, 2967 .llseek = seq_lseek, 2968 .release = seq_release_net, 2969 }; 2970 2971 static int __net_init igmp_net_init(struct net *net) 2972 { 2973 struct proc_dir_entry *pde; 2974 int err; 2975 2976 pde = proc_create("igmp", S_IRUGO, net->proc_net, &igmp_mc_seq_fops); 2977 if (!pde) 2978 goto out_igmp; 2979 pde = proc_create("mcfilter", S_IRUGO, net->proc_net, 2980 &igmp_mcf_seq_fops); 2981 if (!pde) 2982 goto out_mcfilter; 2983 err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET, 2984 SOCK_DGRAM, 0, net); 2985 if (err < 0) { 2986 pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n", 2987 err); 2988 goto out_sock; 2989 } 2990 2991 return 0; 2992 2993 out_sock: 2994 remove_proc_entry("mcfilter", net->proc_net); 2995 out_mcfilter: 2996 remove_proc_entry("igmp", net->proc_net); 2997 out_igmp: 2998 return -ENOMEM; 2999 } 3000 3001 static void __net_exit igmp_net_exit(struct net *net) 3002 { 3003 remove_proc_entry("mcfilter", net->proc_net); 3004 remove_proc_entry("igmp", net->proc_net); 3005 inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk); 3006 } 3007 3008 static struct pernet_operations igmp_net_ops = { 3009 .init = igmp_net_init, 3010 .exit = igmp_net_exit, 3011 }; 3012 #endif 3013 3014 static int igmp_netdev_event(struct notifier_block *this, 3015 unsigned long event, void *ptr) 3016 { 3017 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 3018 struct in_device *in_dev; 3019 3020 switch (event) { 3021 case NETDEV_RESEND_IGMP: 3022 in_dev = __in_dev_get_rtnl(dev); 3023 if (in_dev) 3024 ip_mc_rejoin_groups(in_dev); 3025 break; 3026 default: 3027 break; 3028 } 3029 return NOTIFY_DONE; 3030 } 3031 3032 static struct notifier_block igmp_notifier = { 3033 .notifier_call = igmp_netdev_event, 3034 }; 3035 3036 int __init igmp_mc_init(void) 3037 { 3038 #if defined(CONFIG_PROC_FS) 3039 int err; 3040 3041 err = register_pernet_subsys(&igmp_net_ops); 3042 if (err) 3043 return err; 3044 err = register_netdevice_notifier(&igmp_notifier); 3045 if (err) 3046 goto reg_notif_fail; 3047 return 0; 3048 3049 reg_notif_fail: 3050 unregister_pernet_subsys(&igmp_net_ops); 3051 return err; 3052 #else 3053 return register_netdevice_notifier(&igmp_notifier); 3054 #endif 3055 } 3056