1 /* 2 * Linux NET3: Internet Group Management Protocol [IGMP] 3 * 4 * This code implements the IGMP protocol as defined in RFC1112. There has 5 * been a further revision of this protocol since which is now supported. 6 * 7 * If you have trouble with this module be careful what gcc you have used, 8 * the older version didn't come out right using gcc 2.5.8, the newer one 9 * seems to fall out with gcc 2.6.2. 10 * 11 * Authors: 12 * Alan Cox <alan@lxorguk.ukuu.org.uk> 13 * 14 * This program is free software; you can redistribute it and/or 15 * modify it under the terms of the GNU General Public License 16 * as published by the Free Software Foundation; either version 17 * 2 of the License, or (at your option) any later version. 18 * 19 * Fixes: 20 * 21 * Alan Cox : Added lots of __inline__ to optimise 22 * the memory usage of all the tiny little 23 * functions. 24 * Alan Cox : Dumped the header building experiment. 25 * Alan Cox : Minor tweaks ready for multicast routing 26 * and extended IGMP protocol. 27 * Alan Cox : Removed a load of inline directives. Gcc 2.5.8 28 * writes utterly bogus code otherwise (sigh) 29 * fixed IGMP loopback to behave in the manner 30 * desired by mrouted, fixed the fact it has been 31 * broken since 1.3.6 and cleaned up a few minor 32 * points. 33 * 34 * Chih-Jen Chang : Tried to revise IGMP to Version 2 35 * Tsu-Sheng Tsao E-mail: chihjenc@scf.usc.edu and tsusheng@scf.usc.edu 36 * The enhancements are mainly based on Steve Deering's 37 * ipmulti-3.5 source code. 38 * Chih-Jen Chang : Added the igmp_get_mrouter_info and 39 * Tsu-Sheng Tsao igmp_set_mrouter_info to keep track of 40 * the mrouted version on that device. 41 * Chih-Jen Chang : Added the max_resp_time parameter to 42 * Tsu-Sheng Tsao igmp_heard_query(). Using this parameter 43 * to identify the multicast router version 44 * and do what the IGMP version 2 specified. 45 * Chih-Jen Chang : Added a timer to revert to IGMP V2 router 46 * Tsu-Sheng Tsao if the specified time expired. 47 * Alan Cox : Stop IGMP from 0.0.0.0 being accepted. 48 * Alan Cox : Use GFP_ATOMIC in the right places. 49 * Christian Daudt : igmp timer wasn't set for local group 50 * memberships but was being deleted, 51 * which caused a "del_timer() called 52 * from %p with timer not initialized\n" 53 * message (960131). 54 * Christian Daudt : removed del_timer from 55 * igmp_timer_expire function (960205). 56 * Christian Daudt : igmp_heard_report now only calls 57 * igmp_timer_expire if tm->running is 58 * true (960216). 59 * Malcolm Beattie : ttl comparison wrong in igmp_rcv made 60 * igmp_heard_query never trigger. Expiry 61 * miscalculation fixed in igmp_heard_query 62 * and random() made to return unsigned to 63 * prevent negative expiry times. 64 * Alexey Kuznetsov: Wrong group leaving behaviour, backport 65 * fix from pending 2.1.x patches. 66 * Alan Cox: Forget to enable FDDI support earlier. 67 * Alexey Kuznetsov: Fixed leaving groups on device down. 68 * Alexey Kuznetsov: Accordance to igmp-v2-06 draft. 69 * David L Stevens: IGMPv3 support, with help from 70 * Vinay Kulkarni 71 */ 72 73 #include <linux/module.h> 74 #include <linux/slab.h> 75 #include <linux/uaccess.h> 76 #include <linux/types.h> 77 #include <linux/kernel.h> 78 #include <linux/jiffies.h> 79 #include <linux/string.h> 80 #include <linux/socket.h> 81 #include <linux/sockios.h> 82 #include <linux/in.h> 83 #include <linux/inet.h> 84 #include <linux/netdevice.h> 85 #include <linux/skbuff.h> 86 #include <linux/inetdevice.h> 87 #include <linux/igmp.h> 88 #include <linux/if_arp.h> 89 #include <linux/rtnetlink.h> 90 #include <linux/times.h> 91 #include <linux/pkt_sched.h> 92 #include <linux/byteorder/generic.h> 93 94 #include <net/net_namespace.h> 95 #include <net/arp.h> 96 #include <net/ip.h> 97 #include <net/protocol.h> 98 #include <net/route.h> 99 #include <net/sock.h> 100 #include <net/checksum.h> 101 #include <net/inet_common.h> 102 #include <linux/netfilter_ipv4.h> 103 #ifdef CONFIG_IP_MROUTE 104 #include <linux/mroute.h> 105 #endif 106 #ifdef CONFIG_PROC_FS 107 #include <linux/proc_fs.h> 108 #include <linux/seq_file.h> 109 #endif 110 111 #ifdef CONFIG_IP_MULTICAST 112 /* Parameter names and values are taken from igmp-v2-06 draft */ 113 114 #define IGMP_V1_ROUTER_PRESENT_TIMEOUT (400*HZ) 115 #define IGMP_V2_ROUTER_PRESENT_TIMEOUT (400*HZ) 116 #define IGMP_V2_UNSOLICITED_REPORT_INTERVAL (10*HZ) 117 #define IGMP_V3_UNSOLICITED_REPORT_INTERVAL (1*HZ) 118 #define IGMP_QUERY_RESPONSE_INTERVAL (10*HZ) 119 #define IGMP_QUERY_ROBUSTNESS_VARIABLE 2 120 121 122 #define IGMP_INITIAL_REPORT_DELAY (1) 123 124 /* IGMP_INITIAL_REPORT_DELAY is not from IGMP specs! 125 * IGMP specs require to report membership immediately after 126 * joining a group, but we delay the first report by a 127 * small interval. It seems more natural and still does not 128 * contradict to specs provided this delay is small enough. 129 */ 130 131 #define IGMP_V1_SEEN(in_dev) \ 132 (IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \ 133 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \ 134 ((in_dev)->mr_v1_seen && \ 135 time_before(jiffies, (in_dev)->mr_v1_seen))) 136 #define IGMP_V2_SEEN(in_dev) \ 137 (IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \ 138 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \ 139 ((in_dev)->mr_v2_seen && \ 140 time_before(jiffies, (in_dev)->mr_v2_seen))) 141 142 static int unsolicited_report_interval(struct in_device *in_dev) 143 { 144 int interval_ms, interval_jiffies; 145 146 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) 147 interval_ms = IN_DEV_CONF_GET( 148 in_dev, 149 IGMPV2_UNSOLICITED_REPORT_INTERVAL); 150 else /* v3 */ 151 interval_ms = IN_DEV_CONF_GET( 152 in_dev, 153 IGMPV3_UNSOLICITED_REPORT_INTERVAL); 154 155 interval_jiffies = msecs_to_jiffies(interval_ms); 156 157 /* _timer functions can't handle a delay of 0 jiffies so ensure 158 * we always return a positive value. 159 */ 160 if (interval_jiffies <= 0) 161 interval_jiffies = 1; 162 return interval_jiffies; 163 } 164 165 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im); 166 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im); 167 static void igmpv3_clear_delrec(struct in_device *in_dev); 168 static int sf_setstate(struct ip_mc_list *pmc); 169 static void sf_markstate(struct ip_mc_list *pmc); 170 #endif 171 static void ip_mc_clear_src(struct ip_mc_list *pmc); 172 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 173 int sfcount, __be32 *psfsrc, int delta); 174 175 static void ip_ma_put(struct ip_mc_list *im) 176 { 177 if (refcount_dec_and_test(&im->refcnt)) { 178 in_dev_put(im->interface); 179 kfree_rcu(im, rcu); 180 } 181 } 182 183 #define for_each_pmc_rcu(in_dev, pmc) \ 184 for (pmc = rcu_dereference(in_dev->mc_list); \ 185 pmc != NULL; \ 186 pmc = rcu_dereference(pmc->next_rcu)) 187 188 #define for_each_pmc_rtnl(in_dev, pmc) \ 189 for (pmc = rtnl_dereference(in_dev->mc_list); \ 190 pmc != NULL; \ 191 pmc = rtnl_dereference(pmc->next_rcu)) 192 193 #ifdef CONFIG_IP_MULTICAST 194 195 /* 196 * Timer management 197 */ 198 199 static void igmp_stop_timer(struct ip_mc_list *im) 200 { 201 spin_lock_bh(&im->lock); 202 if (del_timer(&im->timer)) 203 refcount_dec(&im->refcnt); 204 im->tm_running = 0; 205 im->reporter = 0; 206 im->unsolicit_count = 0; 207 spin_unlock_bh(&im->lock); 208 } 209 210 /* It must be called with locked im->lock */ 211 static void igmp_start_timer(struct ip_mc_list *im, int max_delay) 212 { 213 int tv = prandom_u32() % max_delay; 214 215 im->tm_running = 1; 216 if (!mod_timer(&im->timer, jiffies+tv+2)) 217 refcount_inc(&im->refcnt); 218 } 219 220 static void igmp_gq_start_timer(struct in_device *in_dev) 221 { 222 int tv = prandom_u32() % in_dev->mr_maxdelay; 223 unsigned long exp = jiffies + tv + 2; 224 225 if (in_dev->mr_gq_running && 226 time_after_eq(exp, (in_dev->mr_gq_timer).expires)) 227 return; 228 229 in_dev->mr_gq_running = 1; 230 if (!mod_timer(&in_dev->mr_gq_timer, exp)) 231 in_dev_hold(in_dev); 232 } 233 234 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay) 235 { 236 int tv = prandom_u32() % delay; 237 238 if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2)) 239 in_dev_hold(in_dev); 240 } 241 242 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay) 243 { 244 spin_lock_bh(&im->lock); 245 im->unsolicit_count = 0; 246 if (del_timer(&im->timer)) { 247 if ((long)(im->timer.expires-jiffies) < max_delay) { 248 add_timer(&im->timer); 249 im->tm_running = 1; 250 spin_unlock_bh(&im->lock); 251 return; 252 } 253 refcount_dec(&im->refcnt); 254 } 255 igmp_start_timer(im, max_delay); 256 spin_unlock_bh(&im->lock); 257 } 258 259 260 /* 261 * Send an IGMP report. 262 */ 263 264 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4) 265 266 267 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type, 268 int gdeleted, int sdeleted) 269 { 270 switch (type) { 271 case IGMPV3_MODE_IS_INCLUDE: 272 case IGMPV3_MODE_IS_EXCLUDE: 273 if (gdeleted || sdeleted) 274 return 0; 275 if (!(pmc->gsquery && !psf->sf_gsresp)) { 276 if (pmc->sfmode == MCAST_INCLUDE) 277 return 1; 278 /* don't include if this source is excluded 279 * in all filters 280 */ 281 if (psf->sf_count[MCAST_INCLUDE]) 282 return type == IGMPV3_MODE_IS_INCLUDE; 283 return pmc->sfcount[MCAST_EXCLUDE] == 284 psf->sf_count[MCAST_EXCLUDE]; 285 } 286 return 0; 287 case IGMPV3_CHANGE_TO_INCLUDE: 288 if (gdeleted || sdeleted) 289 return 0; 290 return psf->sf_count[MCAST_INCLUDE] != 0; 291 case IGMPV3_CHANGE_TO_EXCLUDE: 292 if (gdeleted || sdeleted) 293 return 0; 294 if (pmc->sfcount[MCAST_EXCLUDE] == 0 || 295 psf->sf_count[MCAST_INCLUDE]) 296 return 0; 297 return pmc->sfcount[MCAST_EXCLUDE] == 298 psf->sf_count[MCAST_EXCLUDE]; 299 case IGMPV3_ALLOW_NEW_SOURCES: 300 if (gdeleted || !psf->sf_crcount) 301 return 0; 302 return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted; 303 case IGMPV3_BLOCK_OLD_SOURCES: 304 if (pmc->sfmode == MCAST_INCLUDE) 305 return gdeleted || (psf->sf_crcount && sdeleted); 306 return psf->sf_crcount && !gdeleted && !sdeleted; 307 } 308 return 0; 309 } 310 311 static int 312 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted) 313 { 314 struct ip_sf_list *psf; 315 int scount = 0; 316 317 for (psf = pmc->sources; psf; psf = psf->sf_next) { 318 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) 319 continue; 320 scount++; 321 } 322 return scount; 323 } 324 325 /* source address selection per RFC 3376 section 4.2.13 */ 326 static __be32 igmpv3_get_srcaddr(struct net_device *dev, 327 const struct flowi4 *fl4) 328 { 329 struct in_device *in_dev = __in_dev_get_rcu(dev); 330 331 if (!in_dev) 332 return htonl(INADDR_ANY); 333 334 for_ifa(in_dev) { 335 if (fl4->saddr == ifa->ifa_local) 336 return fl4->saddr; 337 } endfor_ifa(in_dev); 338 339 return htonl(INADDR_ANY); 340 } 341 342 static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu) 343 { 344 struct sk_buff *skb; 345 struct rtable *rt; 346 struct iphdr *pip; 347 struct igmpv3_report *pig; 348 struct net *net = dev_net(dev); 349 struct flowi4 fl4; 350 int hlen = LL_RESERVED_SPACE(dev); 351 int tlen = dev->needed_tailroom; 352 unsigned int size = mtu; 353 354 while (1) { 355 skb = alloc_skb(size + hlen + tlen, 356 GFP_ATOMIC | __GFP_NOWARN); 357 if (skb) 358 break; 359 size >>= 1; 360 if (size < 256) 361 return NULL; 362 } 363 skb->priority = TC_PRIO_CONTROL; 364 365 rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0, 366 0, 0, 367 IPPROTO_IGMP, 0, dev->ifindex); 368 if (IS_ERR(rt)) { 369 kfree_skb(skb); 370 return NULL; 371 } 372 373 skb_dst_set(skb, &rt->dst); 374 skb->dev = dev; 375 376 skb_reserve(skb, hlen); 377 skb_tailroom_reserve(skb, mtu, tlen); 378 379 skb_reset_network_header(skb); 380 pip = ip_hdr(skb); 381 skb_put(skb, sizeof(struct iphdr) + 4); 382 383 pip->version = 4; 384 pip->ihl = (sizeof(struct iphdr)+4)>>2; 385 pip->tos = 0xc0; 386 pip->frag_off = htons(IP_DF); 387 pip->ttl = 1; 388 pip->daddr = fl4.daddr; 389 390 rcu_read_lock(); 391 pip->saddr = igmpv3_get_srcaddr(dev, &fl4); 392 rcu_read_unlock(); 393 394 pip->protocol = IPPROTO_IGMP; 395 pip->tot_len = 0; /* filled in later */ 396 ip_select_ident(net, skb, NULL); 397 ((u8 *)&pip[1])[0] = IPOPT_RA; 398 ((u8 *)&pip[1])[1] = 4; 399 ((u8 *)&pip[1])[2] = 0; 400 ((u8 *)&pip[1])[3] = 0; 401 402 skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4; 403 skb_put(skb, sizeof(*pig)); 404 pig = igmpv3_report_hdr(skb); 405 pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT; 406 pig->resv1 = 0; 407 pig->csum = 0; 408 pig->resv2 = 0; 409 pig->ngrec = 0; 410 return skb; 411 } 412 413 static int igmpv3_sendpack(struct sk_buff *skb) 414 { 415 struct igmphdr *pig = igmp_hdr(skb); 416 const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb); 417 418 pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen); 419 420 return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb); 421 } 422 423 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel) 424 { 425 return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel); 426 } 427 428 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc, 429 int type, struct igmpv3_grec **ppgr, unsigned int mtu) 430 { 431 struct net_device *dev = pmc->interface->dev; 432 struct igmpv3_report *pih; 433 struct igmpv3_grec *pgr; 434 435 if (!skb) { 436 skb = igmpv3_newpack(dev, mtu); 437 if (!skb) 438 return NULL; 439 } 440 pgr = skb_put(skb, sizeof(struct igmpv3_grec)); 441 pgr->grec_type = type; 442 pgr->grec_auxwords = 0; 443 pgr->grec_nsrcs = 0; 444 pgr->grec_mca = pmc->multiaddr; 445 pih = igmpv3_report_hdr(skb); 446 pih->ngrec = htons(ntohs(pih->ngrec)+1); 447 *ppgr = pgr; 448 return skb; 449 } 450 451 #define AVAILABLE(skb) ((skb) ? skb_availroom(skb) : 0) 452 453 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc, 454 int type, int gdeleted, int sdeleted) 455 { 456 struct net_device *dev = pmc->interface->dev; 457 struct net *net = dev_net(dev); 458 struct igmpv3_report *pih; 459 struct igmpv3_grec *pgr = NULL; 460 struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list; 461 int scount, stotal, first, isquery, truncate; 462 unsigned int mtu; 463 464 if (pmc->multiaddr == IGMP_ALL_HOSTS) 465 return skb; 466 if (ipv4_is_local_multicast(pmc->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports) 467 return skb; 468 469 mtu = READ_ONCE(dev->mtu); 470 if (mtu < IPV4_MIN_MTU) 471 return skb; 472 473 isquery = type == IGMPV3_MODE_IS_INCLUDE || 474 type == IGMPV3_MODE_IS_EXCLUDE; 475 truncate = type == IGMPV3_MODE_IS_EXCLUDE || 476 type == IGMPV3_CHANGE_TO_EXCLUDE; 477 478 stotal = scount = 0; 479 480 psf_list = sdeleted ? &pmc->tomb : &pmc->sources; 481 482 if (!*psf_list) 483 goto empty_source; 484 485 pih = skb ? igmpv3_report_hdr(skb) : NULL; 486 487 /* EX and TO_EX get a fresh packet, if needed */ 488 if (truncate) { 489 if (pih && pih->ngrec && 490 AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) { 491 if (skb) 492 igmpv3_sendpack(skb); 493 skb = igmpv3_newpack(dev, mtu); 494 } 495 } 496 first = 1; 497 psf_prev = NULL; 498 for (psf = *psf_list; psf; psf = psf_next) { 499 __be32 *psrc; 500 501 psf_next = psf->sf_next; 502 503 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) { 504 psf_prev = psf; 505 continue; 506 } 507 508 /* Based on RFC3376 5.1. Should not send source-list change 509 * records when there is a filter mode change. 510 */ 511 if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) || 512 (!gdeleted && pmc->crcount)) && 513 (type == IGMPV3_ALLOW_NEW_SOURCES || 514 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) 515 goto decrease_sf_crcount; 516 517 /* clear marks on query responses */ 518 if (isquery) 519 psf->sf_gsresp = 0; 520 521 if (AVAILABLE(skb) < sizeof(__be32) + 522 first*sizeof(struct igmpv3_grec)) { 523 if (truncate && !first) 524 break; /* truncate these */ 525 if (pgr) 526 pgr->grec_nsrcs = htons(scount); 527 if (skb) 528 igmpv3_sendpack(skb); 529 skb = igmpv3_newpack(dev, mtu); 530 first = 1; 531 scount = 0; 532 } 533 if (first) { 534 skb = add_grhead(skb, pmc, type, &pgr, mtu); 535 first = 0; 536 } 537 if (!skb) 538 return NULL; 539 psrc = skb_put(skb, sizeof(__be32)); 540 *psrc = psf->sf_inaddr; 541 scount++; stotal++; 542 if ((type == IGMPV3_ALLOW_NEW_SOURCES || 543 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) { 544 decrease_sf_crcount: 545 psf->sf_crcount--; 546 if ((sdeleted || gdeleted) && psf->sf_crcount == 0) { 547 if (psf_prev) 548 psf_prev->sf_next = psf->sf_next; 549 else 550 *psf_list = psf->sf_next; 551 kfree(psf); 552 continue; 553 } 554 } 555 psf_prev = psf; 556 } 557 558 empty_source: 559 if (!stotal) { 560 if (type == IGMPV3_ALLOW_NEW_SOURCES || 561 type == IGMPV3_BLOCK_OLD_SOURCES) 562 return skb; 563 if (pmc->crcount || isquery) { 564 /* make sure we have room for group header */ 565 if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) { 566 igmpv3_sendpack(skb); 567 skb = NULL; /* add_grhead will get a new one */ 568 } 569 skb = add_grhead(skb, pmc, type, &pgr, mtu); 570 } 571 } 572 if (pgr) 573 pgr->grec_nsrcs = htons(scount); 574 575 if (isquery) 576 pmc->gsquery = 0; /* clear query state on report */ 577 return skb; 578 } 579 580 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc) 581 { 582 struct sk_buff *skb = NULL; 583 struct net *net = dev_net(in_dev->dev); 584 int type; 585 586 if (!pmc) { 587 rcu_read_lock(); 588 for_each_pmc_rcu(in_dev, pmc) { 589 if (pmc->multiaddr == IGMP_ALL_HOSTS) 590 continue; 591 if (ipv4_is_local_multicast(pmc->multiaddr) && 592 !net->ipv4.sysctl_igmp_llm_reports) 593 continue; 594 spin_lock_bh(&pmc->lock); 595 if (pmc->sfcount[MCAST_EXCLUDE]) 596 type = IGMPV3_MODE_IS_EXCLUDE; 597 else 598 type = IGMPV3_MODE_IS_INCLUDE; 599 skb = add_grec(skb, pmc, type, 0, 0); 600 spin_unlock_bh(&pmc->lock); 601 } 602 rcu_read_unlock(); 603 } else { 604 spin_lock_bh(&pmc->lock); 605 if (pmc->sfcount[MCAST_EXCLUDE]) 606 type = IGMPV3_MODE_IS_EXCLUDE; 607 else 608 type = IGMPV3_MODE_IS_INCLUDE; 609 skb = add_grec(skb, pmc, type, 0, 0); 610 spin_unlock_bh(&pmc->lock); 611 } 612 if (!skb) 613 return 0; 614 return igmpv3_sendpack(skb); 615 } 616 617 /* 618 * remove zero-count source records from a source filter list 619 */ 620 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf) 621 { 622 struct ip_sf_list *psf_prev, *psf_next, *psf; 623 624 psf_prev = NULL; 625 for (psf = *ppsf; psf; psf = psf_next) { 626 psf_next = psf->sf_next; 627 if (psf->sf_crcount == 0) { 628 if (psf_prev) 629 psf_prev->sf_next = psf->sf_next; 630 else 631 *ppsf = psf->sf_next; 632 kfree(psf); 633 } else 634 psf_prev = psf; 635 } 636 } 637 638 static void igmpv3_send_cr(struct in_device *in_dev) 639 { 640 struct ip_mc_list *pmc, *pmc_prev, *pmc_next; 641 struct sk_buff *skb = NULL; 642 int type, dtype; 643 644 rcu_read_lock(); 645 spin_lock_bh(&in_dev->mc_tomb_lock); 646 647 /* deleted MCA's */ 648 pmc_prev = NULL; 649 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) { 650 pmc_next = pmc->next; 651 if (pmc->sfmode == MCAST_INCLUDE) { 652 type = IGMPV3_BLOCK_OLD_SOURCES; 653 dtype = IGMPV3_BLOCK_OLD_SOURCES; 654 skb = add_grec(skb, pmc, type, 1, 0); 655 skb = add_grec(skb, pmc, dtype, 1, 1); 656 } 657 if (pmc->crcount) { 658 if (pmc->sfmode == MCAST_EXCLUDE) { 659 type = IGMPV3_CHANGE_TO_INCLUDE; 660 skb = add_grec(skb, pmc, type, 1, 0); 661 } 662 pmc->crcount--; 663 if (pmc->crcount == 0) { 664 igmpv3_clear_zeros(&pmc->tomb); 665 igmpv3_clear_zeros(&pmc->sources); 666 } 667 } 668 if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) { 669 if (pmc_prev) 670 pmc_prev->next = pmc_next; 671 else 672 in_dev->mc_tomb = pmc_next; 673 in_dev_put(pmc->interface); 674 kfree(pmc); 675 } else 676 pmc_prev = pmc; 677 } 678 spin_unlock_bh(&in_dev->mc_tomb_lock); 679 680 /* change recs */ 681 for_each_pmc_rcu(in_dev, pmc) { 682 spin_lock_bh(&pmc->lock); 683 if (pmc->sfcount[MCAST_EXCLUDE]) { 684 type = IGMPV3_BLOCK_OLD_SOURCES; 685 dtype = IGMPV3_ALLOW_NEW_SOURCES; 686 } else { 687 type = IGMPV3_ALLOW_NEW_SOURCES; 688 dtype = IGMPV3_BLOCK_OLD_SOURCES; 689 } 690 skb = add_grec(skb, pmc, type, 0, 0); 691 skb = add_grec(skb, pmc, dtype, 0, 1); /* deleted sources */ 692 693 /* filter mode changes */ 694 if (pmc->crcount) { 695 if (pmc->sfmode == MCAST_EXCLUDE) 696 type = IGMPV3_CHANGE_TO_EXCLUDE; 697 else 698 type = IGMPV3_CHANGE_TO_INCLUDE; 699 skb = add_grec(skb, pmc, type, 0, 0); 700 pmc->crcount--; 701 } 702 spin_unlock_bh(&pmc->lock); 703 } 704 rcu_read_unlock(); 705 706 if (!skb) 707 return; 708 (void) igmpv3_sendpack(skb); 709 } 710 711 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc, 712 int type) 713 { 714 struct sk_buff *skb; 715 struct iphdr *iph; 716 struct igmphdr *ih; 717 struct rtable *rt; 718 struct net_device *dev = in_dev->dev; 719 struct net *net = dev_net(dev); 720 __be32 group = pmc ? pmc->multiaddr : 0; 721 struct flowi4 fl4; 722 __be32 dst; 723 int hlen, tlen; 724 725 if (type == IGMPV3_HOST_MEMBERSHIP_REPORT) 726 return igmpv3_send_report(in_dev, pmc); 727 728 if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports) 729 return 0; 730 731 if (type == IGMP_HOST_LEAVE_MESSAGE) 732 dst = IGMP_ALL_ROUTER; 733 else 734 dst = group; 735 736 rt = ip_route_output_ports(net, &fl4, NULL, dst, 0, 737 0, 0, 738 IPPROTO_IGMP, 0, dev->ifindex); 739 if (IS_ERR(rt)) 740 return -1; 741 742 hlen = LL_RESERVED_SPACE(dev); 743 tlen = dev->needed_tailroom; 744 skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC); 745 if (!skb) { 746 ip_rt_put(rt); 747 return -1; 748 } 749 skb->priority = TC_PRIO_CONTROL; 750 751 skb_dst_set(skb, &rt->dst); 752 753 skb_reserve(skb, hlen); 754 755 skb_reset_network_header(skb); 756 iph = ip_hdr(skb); 757 skb_put(skb, sizeof(struct iphdr) + 4); 758 759 iph->version = 4; 760 iph->ihl = (sizeof(struct iphdr)+4)>>2; 761 iph->tos = 0xc0; 762 iph->frag_off = htons(IP_DF); 763 iph->ttl = 1; 764 iph->daddr = dst; 765 iph->saddr = fl4.saddr; 766 iph->protocol = IPPROTO_IGMP; 767 ip_select_ident(net, skb, NULL); 768 ((u8 *)&iph[1])[0] = IPOPT_RA; 769 ((u8 *)&iph[1])[1] = 4; 770 ((u8 *)&iph[1])[2] = 0; 771 ((u8 *)&iph[1])[3] = 0; 772 773 ih = skb_put(skb, sizeof(struct igmphdr)); 774 ih->type = type; 775 ih->code = 0; 776 ih->csum = 0; 777 ih->group = group; 778 ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr)); 779 780 return ip_local_out(net, skb->sk, skb); 781 } 782 783 static void igmp_gq_timer_expire(struct timer_list *t) 784 { 785 struct in_device *in_dev = from_timer(in_dev, t, mr_gq_timer); 786 787 in_dev->mr_gq_running = 0; 788 igmpv3_send_report(in_dev, NULL); 789 in_dev_put(in_dev); 790 } 791 792 static void igmp_ifc_timer_expire(struct timer_list *t) 793 { 794 struct in_device *in_dev = from_timer(in_dev, t, mr_ifc_timer); 795 796 igmpv3_send_cr(in_dev); 797 if (in_dev->mr_ifc_count) { 798 in_dev->mr_ifc_count--; 799 igmp_ifc_start_timer(in_dev, 800 unsolicited_report_interval(in_dev)); 801 } 802 in_dev_put(in_dev); 803 } 804 805 static void igmp_ifc_event(struct in_device *in_dev) 806 { 807 struct net *net = dev_net(in_dev->dev); 808 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) 809 return; 810 in_dev->mr_ifc_count = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 811 igmp_ifc_start_timer(in_dev, 1); 812 } 813 814 815 static void igmp_timer_expire(struct timer_list *t) 816 { 817 struct ip_mc_list *im = from_timer(im, t, timer); 818 struct in_device *in_dev = im->interface; 819 820 spin_lock(&im->lock); 821 im->tm_running = 0; 822 823 if (im->unsolicit_count) { 824 im->unsolicit_count--; 825 igmp_start_timer(im, unsolicited_report_interval(in_dev)); 826 } 827 im->reporter = 1; 828 spin_unlock(&im->lock); 829 830 if (IGMP_V1_SEEN(in_dev)) 831 igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT); 832 else if (IGMP_V2_SEEN(in_dev)) 833 igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT); 834 else 835 igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT); 836 837 ip_ma_put(im); 838 } 839 840 /* mark EXCLUDE-mode sources */ 841 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs) 842 { 843 struct ip_sf_list *psf; 844 int i, scount; 845 846 scount = 0; 847 for (psf = pmc->sources; psf; psf = psf->sf_next) { 848 if (scount == nsrcs) 849 break; 850 for (i = 0; i < nsrcs; i++) { 851 /* skip inactive filters */ 852 if (psf->sf_count[MCAST_INCLUDE] || 853 pmc->sfcount[MCAST_EXCLUDE] != 854 psf->sf_count[MCAST_EXCLUDE]) 855 break; 856 if (srcs[i] == psf->sf_inaddr) { 857 scount++; 858 break; 859 } 860 } 861 } 862 pmc->gsquery = 0; 863 if (scount == nsrcs) /* all sources excluded */ 864 return 0; 865 return 1; 866 } 867 868 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs) 869 { 870 struct ip_sf_list *psf; 871 int i, scount; 872 873 if (pmc->sfmode == MCAST_EXCLUDE) 874 return igmp_xmarksources(pmc, nsrcs, srcs); 875 876 /* mark INCLUDE-mode sources */ 877 scount = 0; 878 for (psf = pmc->sources; psf; psf = psf->sf_next) { 879 if (scount == nsrcs) 880 break; 881 for (i = 0; i < nsrcs; i++) 882 if (srcs[i] == psf->sf_inaddr) { 883 psf->sf_gsresp = 1; 884 scount++; 885 break; 886 } 887 } 888 if (!scount) { 889 pmc->gsquery = 0; 890 return 0; 891 } 892 pmc->gsquery = 1; 893 return 1; 894 } 895 896 /* return true if packet was dropped */ 897 static bool igmp_heard_report(struct in_device *in_dev, __be32 group) 898 { 899 struct ip_mc_list *im; 900 struct net *net = dev_net(in_dev->dev); 901 902 /* Timers are only set for non-local groups */ 903 904 if (group == IGMP_ALL_HOSTS) 905 return false; 906 if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports) 907 return false; 908 909 rcu_read_lock(); 910 for_each_pmc_rcu(in_dev, im) { 911 if (im->multiaddr == group) { 912 igmp_stop_timer(im); 913 break; 914 } 915 } 916 rcu_read_unlock(); 917 return false; 918 } 919 920 /* return true if packet was dropped */ 921 static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb, 922 int len) 923 { 924 struct igmphdr *ih = igmp_hdr(skb); 925 struct igmpv3_query *ih3 = igmpv3_query_hdr(skb); 926 struct ip_mc_list *im; 927 __be32 group = ih->group; 928 int max_delay; 929 int mark = 0; 930 struct net *net = dev_net(in_dev->dev); 931 932 933 if (len == 8) { 934 if (ih->code == 0) { 935 /* Alas, old v1 router presents here. */ 936 937 max_delay = IGMP_QUERY_RESPONSE_INTERVAL; 938 in_dev->mr_v1_seen = jiffies + 939 IGMP_V1_ROUTER_PRESENT_TIMEOUT; 940 group = 0; 941 } else { 942 /* v2 router present */ 943 max_delay = ih->code*(HZ/IGMP_TIMER_SCALE); 944 in_dev->mr_v2_seen = jiffies + 945 IGMP_V2_ROUTER_PRESENT_TIMEOUT; 946 } 947 /* cancel the interface change timer */ 948 in_dev->mr_ifc_count = 0; 949 if (del_timer(&in_dev->mr_ifc_timer)) 950 __in_dev_put(in_dev); 951 /* clear deleted report items */ 952 igmpv3_clear_delrec(in_dev); 953 } else if (len < 12) { 954 return true; /* ignore bogus packet; freed by caller */ 955 } else if (IGMP_V1_SEEN(in_dev)) { 956 /* This is a v3 query with v1 queriers present */ 957 max_delay = IGMP_QUERY_RESPONSE_INTERVAL; 958 group = 0; 959 } else if (IGMP_V2_SEEN(in_dev)) { 960 /* this is a v3 query with v2 queriers present; 961 * Interpretation of the max_delay code is problematic here. 962 * A real v2 host would use ih_code directly, while v3 has a 963 * different encoding. We use the v3 encoding as more likely 964 * to be intended in a v3 query. 965 */ 966 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE); 967 if (!max_delay) 968 max_delay = 1; /* can't mod w/ 0 */ 969 } else { /* v3 */ 970 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) 971 return true; 972 973 ih3 = igmpv3_query_hdr(skb); 974 if (ih3->nsrcs) { 975 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query) 976 + ntohs(ih3->nsrcs)*sizeof(__be32))) 977 return true; 978 ih3 = igmpv3_query_hdr(skb); 979 } 980 981 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE); 982 if (!max_delay) 983 max_delay = 1; /* can't mod w/ 0 */ 984 in_dev->mr_maxdelay = max_delay; 985 if (ih3->qrv) 986 in_dev->mr_qrv = ih3->qrv; 987 if (!group) { /* general query */ 988 if (ih3->nsrcs) 989 return true; /* no sources allowed */ 990 igmp_gq_start_timer(in_dev); 991 return false; 992 } 993 /* mark sources to include, if group & source-specific */ 994 mark = ih3->nsrcs != 0; 995 } 996 997 /* 998 * - Start the timers in all of our membership records 999 * that the query applies to for the interface on 1000 * which the query arrived excl. those that belong 1001 * to a "local" group (224.0.0.X) 1002 * - For timers already running check if they need to 1003 * be reset. 1004 * - Use the igmp->igmp_code field as the maximum 1005 * delay possible 1006 */ 1007 rcu_read_lock(); 1008 for_each_pmc_rcu(in_dev, im) { 1009 int changed; 1010 1011 if (group && group != im->multiaddr) 1012 continue; 1013 if (im->multiaddr == IGMP_ALL_HOSTS) 1014 continue; 1015 if (ipv4_is_local_multicast(im->multiaddr) && 1016 !net->ipv4.sysctl_igmp_llm_reports) 1017 continue; 1018 spin_lock_bh(&im->lock); 1019 if (im->tm_running) 1020 im->gsquery = im->gsquery && mark; 1021 else 1022 im->gsquery = mark; 1023 changed = !im->gsquery || 1024 igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs); 1025 spin_unlock_bh(&im->lock); 1026 if (changed) 1027 igmp_mod_timer(im, max_delay); 1028 } 1029 rcu_read_unlock(); 1030 return false; 1031 } 1032 1033 /* called in rcu_read_lock() section */ 1034 int igmp_rcv(struct sk_buff *skb) 1035 { 1036 /* This basically follows the spec line by line -- see RFC1112 */ 1037 struct igmphdr *ih; 1038 struct net_device *dev = skb->dev; 1039 struct in_device *in_dev; 1040 int len = skb->len; 1041 bool dropped = true; 1042 1043 if (netif_is_l3_master(dev)) { 1044 dev = dev_get_by_index_rcu(dev_net(dev), IPCB(skb)->iif); 1045 if (!dev) 1046 goto drop; 1047 } 1048 1049 in_dev = __in_dev_get_rcu(dev); 1050 if (!in_dev) 1051 goto drop; 1052 1053 if (!pskb_may_pull(skb, sizeof(struct igmphdr))) 1054 goto drop; 1055 1056 if (skb_checksum_simple_validate(skb)) 1057 goto drop; 1058 1059 ih = igmp_hdr(skb); 1060 switch (ih->type) { 1061 case IGMP_HOST_MEMBERSHIP_QUERY: 1062 dropped = igmp_heard_query(in_dev, skb, len); 1063 break; 1064 case IGMP_HOST_MEMBERSHIP_REPORT: 1065 case IGMPV2_HOST_MEMBERSHIP_REPORT: 1066 /* Is it our report looped back? */ 1067 if (rt_is_output_route(skb_rtable(skb))) 1068 break; 1069 /* don't rely on MC router hearing unicast reports */ 1070 if (skb->pkt_type == PACKET_MULTICAST || 1071 skb->pkt_type == PACKET_BROADCAST) 1072 dropped = igmp_heard_report(in_dev, ih->group); 1073 break; 1074 case IGMP_PIM: 1075 #ifdef CONFIG_IP_PIMSM_V1 1076 return pim_rcv_v1(skb); 1077 #endif 1078 case IGMPV3_HOST_MEMBERSHIP_REPORT: 1079 case IGMP_DVMRP: 1080 case IGMP_TRACE: 1081 case IGMP_HOST_LEAVE_MESSAGE: 1082 case IGMP_MTRACE: 1083 case IGMP_MTRACE_RESP: 1084 break; 1085 default: 1086 break; 1087 } 1088 1089 drop: 1090 if (dropped) 1091 kfree_skb(skb); 1092 else 1093 consume_skb(skb); 1094 return 0; 1095 } 1096 1097 #endif 1098 1099 1100 /* 1101 * Add a filter to a device 1102 */ 1103 1104 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr) 1105 { 1106 char buf[MAX_ADDR_LEN]; 1107 struct net_device *dev = in_dev->dev; 1108 1109 /* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG. 1110 We will get multicast token leakage, when IFF_MULTICAST 1111 is changed. This check should be done in ndo_set_rx_mode 1112 routine. Something sort of: 1113 if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; } 1114 --ANK 1115 */ 1116 if (arp_mc_map(addr, buf, dev, 0) == 0) 1117 dev_mc_add(dev, buf); 1118 } 1119 1120 /* 1121 * Remove a filter from a device 1122 */ 1123 1124 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr) 1125 { 1126 char buf[MAX_ADDR_LEN]; 1127 struct net_device *dev = in_dev->dev; 1128 1129 if (arp_mc_map(addr, buf, dev, 0) == 0) 1130 dev_mc_del(dev, buf); 1131 } 1132 1133 #ifdef CONFIG_IP_MULTICAST 1134 /* 1135 * deleted ip_mc_list manipulation 1136 */ 1137 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im) 1138 { 1139 struct ip_mc_list *pmc; 1140 struct net *net = dev_net(in_dev->dev); 1141 1142 /* this is an "ip_mc_list" for convenience; only the fields below 1143 * are actually used. In particular, the refcnt and users are not 1144 * used for management of the delete list. Using the same structure 1145 * for deleted items allows change reports to use common code with 1146 * non-deleted or query-response MCA's. 1147 */ 1148 pmc = kzalloc(sizeof(*pmc), GFP_KERNEL); 1149 if (!pmc) 1150 return; 1151 spin_lock_init(&pmc->lock); 1152 spin_lock_bh(&im->lock); 1153 pmc->interface = im->interface; 1154 in_dev_hold(in_dev); 1155 pmc->multiaddr = im->multiaddr; 1156 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1157 pmc->sfmode = im->sfmode; 1158 if (pmc->sfmode == MCAST_INCLUDE) { 1159 struct ip_sf_list *psf; 1160 1161 pmc->tomb = im->tomb; 1162 pmc->sources = im->sources; 1163 im->tomb = im->sources = NULL; 1164 for (psf = pmc->sources; psf; psf = psf->sf_next) 1165 psf->sf_crcount = pmc->crcount; 1166 } 1167 spin_unlock_bh(&im->lock); 1168 1169 spin_lock_bh(&in_dev->mc_tomb_lock); 1170 pmc->next = in_dev->mc_tomb; 1171 in_dev->mc_tomb = pmc; 1172 spin_unlock_bh(&in_dev->mc_tomb_lock); 1173 } 1174 1175 /* 1176 * restore ip_mc_list deleted records 1177 */ 1178 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im) 1179 { 1180 struct ip_mc_list *pmc, *pmc_prev; 1181 struct ip_sf_list *psf; 1182 struct net *net = dev_net(in_dev->dev); 1183 __be32 multiaddr = im->multiaddr; 1184 1185 spin_lock_bh(&in_dev->mc_tomb_lock); 1186 pmc_prev = NULL; 1187 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) { 1188 if (pmc->multiaddr == multiaddr) 1189 break; 1190 pmc_prev = pmc; 1191 } 1192 if (pmc) { 1193 if (pmc_prev) 1194 pmc_prev->next = pmc->next; 1195 else 1196 in_dev->mc_tomb = pmc->next; 1197 } 1198 spin_unlock_bh(&in_dev->mc_tomb_lock); 1199 1200 spin_lock_bh(&im->lock); 1201 if (pmc) { 1202 im->interface = pmc->interface; 1203 im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1204 im->sfmode = pmc->sfmode; 1205 if (pmc->sfmode == MCAST_INCLUDE) { 1206 im->tomb = pmc->tomb; 1207 im->sources = pmc->sources; 1208 for (psf = im->sources; psf; psf = psf->sf_next) 1209 psf->sf_crcount = im->crcount; 1210 } 1211 in_dev_put(pmc->interface); 1212 kfree(pmc); 1213 } 1214 spin_unlock_bh(&im->lock); 1215 } 1216 1217 /* 1218 * flush ip_mc_list deleted records 1219 */ 1220 static void igmpv3_clear_delrec(struct in_device *in_dev) 1221 { 1222 struct ip_mc_list *pmc, *nextpmc; 1223 1224 spin_lock_bh(&in_dev->mc_tomb_lock); 1225 pmc = in_dev->mc_tomb; 1226 in_dev->mc_tomb = NULL; 1227 spin_unlock_bh(&in_dev->mc_tomb_lock); 1228 1229 for (; pmc; pmc = nextpmc) { 1230 nextpmc = pmc->next; 1231 ip_mc_clear_src(pmc); 1232 in_dev_put(pmc->interface); 1233 kfree(pmc); 1234 } 1235 /* clear dead sources, too */ 1236 rcu_read_lock(); 1237 for_each_pmc_rcu(in_dev, pmc) { 1238 struct ip_sf_list *psf, *psf_next; 1239 1240 spin_lock_bh(&pmc->lock); 1241 psf = pmc->tomb; 1242 pmc->tomb = NULL; 1243 spin_unlock_bh(&pmc->lock); 1244 for (; psf; psf = psf_next) { 1245 psf_next = psf->sf_next; 1246 kfree(psf); 1247 } 1248 } 1249 rcu_read_unlock(); 1250 } 1251 #endif 1252 1253 static void igmp_group_dropped(struct ip_mc_list *im) 1254 { 1255 struct in_device *in_dev = im->interface; 1256 #ifdef CONFIG_IP_MULTICAST 1257 struct net *net = dev_net(in_dev->dev); 1258 int reporter; 1259 #endif 1260 1261 if (im->loaded) { 1262 im->loaded = 0; 1263 ip_mc_filter_del(in_dev, im->multiaddr); 1264 } 1265 1266 #ifdef CONFIG_IP_MULTICAST 1267 if (im->multiaddr == IGMP_ALL_HOSTS) 1268 return; 1269 if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports) 1270 return; 1271 1272 reporter = im->reporter; 1273 igmp_stop_timer(im); 1274 1275 if (!in_dev->dead) { 1276 if (IGMP_V1_SEEN(in_dev)) 1277 return; 1278 if (IGMP_V2_SEEN(in_dev)) { 1279 if (reporter) 1280 igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE); 1281 return; 1282 } 1283 /* IGMPv3 */ 1284 igmpv3_add_delrec(in_dev, im); 1285 1286 igmp_ifc_event(in_dev); 1287 } 1288 #endif 1289 } 1290 1291 static void igmp_group_added(struct ip_mc_list *im) 1292 { 1293 struct in_device *in_dev = im->interface; 1294 #ifdef CONFIG_IP_MULTICAST 1295 struct net *net = dev_net(in_dev->dev); 1296 #endif 1297 1298 if (im->loaded == 0) { 1299 im->loaded = 1; 1300 ip_mc_filter_add(in_dev, im->multiaddr); 1301 } 1302 1303 #ifdef CONFIG_IP_MULTICAST 1304 if (im->multiaddr == IGMP_ALL_HOSTS) 1305 return; 1306 if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports) 1307 return; 1308 1309 if (in_dev->dead) 1310 return; 1311 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) { 1312 spin_lock_bh(&im->lock); 1313 igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY); 1314 spin_unlock_bh(&im->lock); 1315 return; 1316 } 1317 /* else, v3 */ 1318 1319 im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1320 igmp_ifc_event(in_dev); 1321 #endif 1322 } 1323 1324 1325 /* 1326 * Multicast list managers 1327 */ 1328 1329 static u32 ip_mc_hash(const struct ip_mc_list *im) 1330 { 1331 return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG); 1332 } 1333 1334 static void ip_mc_hash_add(struct in_device *in_dev, 1335 struct ip_mc_list *im) 1336 { 1337 struct ip_mc_list __rcu **mc_hash; 1338 u32 hash; 1339 1340 mc_hash = rtnl_dereference(in_dev->mc_hash); 1341 if (mc_hash) { 1342 hash = ip_mc_hash(im); 1343 im->next_hash = mc_hash[hash]; 1344 rcu_assign_pointer(mc_hash[hash], im); 1345 return; 1346 } 1347 1348 /* do not use a hash table for small number of items */ 1349 if (in_dev->mc_count < 4) 1350 return; 1351 1352 mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG, 1353 GFP_KERNEL); 1354 if (!mc_hash) 1355 return; 1356 1357 for_each_pmc_rtnl(in_dev, im) { 1358 hash = ip_mc_hash(im); 1359 im->next_hash = mc_hash[hash]; 1360 RCU_INIT_POINTER(mc_hash[hash], im); 1361 } 1362 1363 rcu_assign_pointer(in_dev->mc_hash, mc_hash); 1364 } 1365 1366 static void ip_mc_hash_remove(struct in_device *in_dev, 1367 struct ip_mc_list *im) 1368 { 1369 struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash); 1370 struct ip_mc_list *aux; 1371 1372 if (!mc_hash) 1373 return; 1374 mc_hash += ip_mc_hash(im); 1375 while ((aux = rtnl_dereference(*mc_hash)) != im) 1376 mc_hash = &aux->next_hash; 1377 *mc_hash = im->next_hash; 1378 } 1379 1380 1381 /* 1382 * A socket has joined a multicast group on device dev. 1383 */ 1384 1385 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr) 1386 { 1387 struct ip_mc_list *im; 1388 #ifdef CONFIG_IP_MULTICAST 1389 struct net *net = dev_net(in_dev->dev); 1390 #endif 1391 1392 ASSERT_RTNL(); 1393 1394 for_each_pmc_rtnl(in_dev, im) { 1395 if (im->multiaddr == addr) { 1396 im->users++; 1397 ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0); 1398 goto out; 1399 } 1400 } 1401 1402 im = kzalloc(sizeof(*im), GFP_KERNEL); 1403 if (!im) 1404 goto out; 1405 1406 im->users = 1; 1407 im->interface = in_dev; 1408 in_dev_hold(in_dev); 1409 im->multiaddr = addr; 1410 /* initial mode is (EX, empty) */ 1411 im->sfmode = MCAST_EXCLUDE; 1412 im->sfcount[MCAST_EXCLUDE] = 1; 1413 refcount_set(&im->refcnt, 1); 1414 spin_lock_init(&im->lock); 1415 #ifdef CONFIG_IP_MULTICAST 1416 timer_setup(&im->timer, igmp_timer_expire, 0); 1417 im->unsolicit_count = net->ipv4.sysctl_igmp_qrv; 1418 #endif 1419 1420 im->next_rcu = in_dev->mc_list; 1421 in_dev->mc_count++; 1422 rcu_assign_pointer(in_dev->mc_list, im); 1423 1424 ip_mc_hash_add(in_dev, im); 1425 1426 #ifdef CONFIG_IP_MULTICAST 1427 igmpv3_del_delrec(in_dev, im); 1428 #endif 1429 igmp_group_added(im); 1430 if (!in_dev->dead) 1431 ip_rt_multicast_event(in_dev); 1432 out: 1433 return; 1434 } 1435 EXPORT_SYMBOL(ip_mc_inc_group); 1436 1437 static int ip_mc_check_iphdr(struct sk_buff *skb) 1438 { 1439 const struct iphdr *iph; 1440 unsigned int len; 1441 unsigned int offset = skb_network_offset(skb) + sizeof(*iph); 1442 1443 if (!pskb_may_pull(skb, offset)) 1444 return -EINVAL; 1445 1446 iph = ip_hdr(skb); 1447 1448 if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph)) 1449 return -EINVAL; 1450 1451 offset += ip_hdrlen(skb) - sizeof(*iph); 1452 1453 if (!pskb_may_pull(skb, offset)) 1454 return -EINVAL; 1455 1456 iph = ip_hdr(skb); 1457 1458 if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl))) 1459 return -EINVAL; 1460 1461 len = skb_network_offset(skb) + ntohs(iph->tot_len); 1462 if (skb->len < len || len < offset) 1463 return -EINVAL; 1464 1465 skb_set_transport_header(skb, offset); 1466 1467 return 0; 1468 } 1469 1470 static int ip_mc_check_igmp_reportv3(struct sk_buff *skb) 1471 { 1472 unsigned int len = skb_transport_offset(skb); 1473 1474 len += sizeof(struct igmpv3_report); 1475 1476 return pskb_may_pull(skb, len) ? 0 : -EINVAL; 1477 } 1478 1479 static int ip_mc_check_igmp_query(struct sk_buff *skb) 1480 { 1481 unsigned int len = skb_transport_offset(skb); 1482 1483 len += sizeof(struct igmphdr); 1484 if (skb->len < len) 1485 return -EINVAL; 1486 1487 /* IGMPv{1,2}? */ 1488 if (skb->len != len) { 1489 /* or IGMPv3? */ 1490 len += sizeof(struct igmpv3_query) - sizeof(struct igmphdr); 1491 if (skb->len < len || !pskb_may_pull(skb, len)) 1492 return -EINVAL; 1493 } 1494 1495 /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer 1496 * all-systems destination addresses (224.0.0.1) for general queries 1497 */ 1498 if (!igmp_hdr(skb)->group && 1499 ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP)) 1500 return -EINVAL; 1501 1502 return 0; 1503 } 1504 1505 static int ip_mc_check_igmp_msg(struct sk_buff *skb) 1506 { 1507 switch (igmp_hdr(skb)->type) { 1508 case IGMP_HOST_LEAVE_MESSAGE: 1509 case IGMP_HOST_MEMBERSHIP_REPORT: 1510 case IGMPV2_HOST_MEMBERSHIP_REPORT: 1511 /* fall through */ 1512 return 0; 1513 case IGMPV3_HOST_MEMBERSHIP_REPORT: 1514 return ip_mc_check_igmp_reportv3(skb); 1515 case IGMP_HOST_MEMBERSHIP_QUERY: 1516 return ip_mc_check_igmp_query(skb); 1517 default: 1518 return -ENOMSG; 1519 } 1520 } 1521 1522 static inline __sum16 ip_mc_validate_checksum(struct sk_buff *skb) 1523 { 1524 return skb_checksum_simple_validate(skb); 1525 } 1526 1527 static int __ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed) 1528 1529 { 1530 struct sk_buff *skb_chk; 1531 unsigned int transport_len; 1532 unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr); 1533 int ret = -EINVAL; 1534 1535 transport_len = ntohs(ip_hdr(skb)->tot_len) - ip_hdrlen(skb); 1536 1537 skb_chk = skb_checksum_trimmed(skb, transport_len, 1538 ip_mc_validate_checksum); 1539 if (!skb_chk) 1540 goto err; 1541 1542 if (!pskb_may_pull(skb_chk, len)) 1543 goto err; 1544 1545 ret = ip_mc_check_igmp_msg(skb_chk); 1546 if (ret) 1547 goto err; 1548 1549 if (skb_trimmed) 1550 *skb_trimmed = skb_chk; 1551 /* free now unneeded clone */ 1552 else if (skb_chk != skb) 1553 kfree_skb(skb_chk); 1554 1555 ret = 0; 1556 1557 err: 1558 if (ret && skb_chk && skb_chk != skb) 1559 kfree_skb(skb_chk); 1560 1561 return ret; 1562 } 1563 1564 /** 1565 * ip_mc_check_igmp - checks whether this is a sane IGMP packet 1566 * @skb: the skb to validate 1567 * @skb_trimmed: to store an skb pointer trimmed to IPv4 packet tail (optional) 1568 * 1569 * Checks whether an IPv4 packet is a valid IGMP packet. If so sets 1570 * skb transport header accordingly and returns zero. 1571 * 1572 * -EINVAL: A broken packet was detected, i.e. it violates some internet 1573 * standard 1574 * -ENOMSG: IP header validation succeeded but it is not an IGMP packet. 1575 * -ENOMEM: A memory allocation failure happened. 1576 * 1577 * Optionally, an skb pointer might be provided via skb_trimmed (or set it 1578 * to NULL): After parsing an IGMP packet successfully it will point to 1579 * an skb which has its tail aligned to the IP packet end. This might 1580 * either be the originally provided skb or a trimmed, cloned version if 1581 * the skb frame had data beyond the IP packet. A cloned skb allows us 1582 * to leave the original skb and its full frame unchanged (which might be 1583 * desirable for layer 2 frame jugglers). 1584 * 1585 * Caller needs to set the skb network header and free any returned skb if it 1586 * differs from the provided skb. 1587 */ 1588 int ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed) 1589 { 1590 int ret = ip_mc_check_iphdr(skb); 1591 1592 if (ret < 0) 1593 return ret; 1594 1595 if (ip_hdr(skb)->protocol != IPPROTO_IGMP) 1596 return -ENOMSG; 1597 1598 return __ip_mc_check_igmp(skb, skb_trimmed); 1599 } 1600 EXPORT_SYMBOL(ip_mc_check_igmp); 1601 1602 /* 1603 * Resend IGMP JOIN report; used by netdev notifier. 1604 */ 1605 static void ip_mc_rejoin_groups(struct in_device *in_dev) 1606 { 1607 #ifdef CONFIG_IP_MULTICAST 1608 struct ip_mc_list *im; 1609 int type; 1610 struct net *net = dev_net(in_dev->dev); 1611 1612 ASSERT_RTNL(); 1613 1614 for_each_pmc_rtnl(in_dev, im) { 1615 if (im->multiaddr == IGMP_ALL_HOSTS) 1616 continue; 1617 if (ipv4_is_local_multicast(im->multiaddr) && 1618 !net->ipv4.sysctl_igmp_llm_reports) 1619 continue; 1620 1621 /* a failover is happening and switches 1622 * must be notified immediately 1623 */ 1624 if (IGMP_V1_SEEN(in_dev)) 1625 type = IGMP_HOST_MEMBERSHIP_REPORT; 1626 else if (IGMP_V2_SEEN(in_dev)) 1627 type = IGMPV2_HOST_MEMBERSHIP_REPORT; 1628 else 1629 type = IGMPV3_HOST_MEMBERSHIP_REPORT; 1630 igmp_send_report(in_dev, im, type); 1631 } 1632 #endif 1633 } 1634 1635 /* 1636 * A socket has left a multicast group on device dev 1637 */ 1638 1639 void ip_mc_dec_group(struct in_device *in_dev, __be32 addr) 1640 { 1641 struct ip_mc_list *i; 1642 struct ip_mc_list __rcu **ip; 1643 1644 ASSERT_RTNL(); 1645 1646 for (ip = &in_dev->mc_list; 1647 (i = rtnl_dereference(*ip)) != NULL; 1648 ip = &i->next_rcu) { 1649 if (i->multiaddr == addr) { 1650 if (--i->users == 0) { 1651 ip_mc_hash_remove(in_dev, i); 1652 *ip = i->next_rcu; 1653 in_dev->mc_count--; 1654 igmp_group_dropped(i); 1655 ip_mc_clear_src(i); 1656 1657 if (!in_dev->dead) 1658 ip_rt_multicast_event(in_dev); 1659 1660 ip_ma_put(i); 1661 return; 1662 } 1663 break; 1664 } 1665 } 1666 } 1667 EXPORT_SYMBOL(ip_mc_dec_group); 1668 1669 /* Device changing type */ 1670 1671 void ip_mc_unmap(struct in_device *in_dev) 1672 { 1673 struct ip_mc_list *pmc; 1674 1675 ASSERT_RTNL(); 1676 1677 for_each_pmc_rtnl(in_dev, pmc) 1678 igmp_group_dropped(pmc); 1679 } 1680 1681 void ip_mc_remap(struct in_device *in_dev) 1682 { 1683 struct ip_mc_list *pmc; 1684 1685 ASSERT_RTNL(); 1686 1687 for_each_pmc_rtnl(in_dev, pmc) { 1688 #ifdef CONFIG_IP_MULTICAST 1689 igmpv3_del_delrec(in_dev, pmc); 1690 #endif 1691 igmp_group_added(pmc); 1692 } 1693 } 1694 1695 /* Device going down */ 1696 1697 void ip_mc_down(struct in_device *in_dev) 1698 { 1699 struct ip_mc_list *pmc; 1700 1701 ASSERT_RTNL(); 1702 1703 for_each_pmc_rtnl(in_dev, pmc) 1704 igmp_group_dropped(pmc); 1705 1706 #ifdef CONFIG_IP_MULTICAST 1707 in_dev->mr_ifc_count = 0; 1708 if (del_timer(&in_dev->mr_ifc_timer)) 1709 __in_dev_put(in_dev); 1710 in_dev->mr_gq_running = 0; 1711 if (del_timer(&in_dev->mr_gq_timer)) 1712 __in_dev_put(in_dev); 1713 #endif 1714 1715 ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS); 1716 } 1717 1718 void ip_mc_init_dev(struct in_device *in_dev) 1719 { 1720 #ifdef CONFIG_IP_MULTICAST 1721 struct net *net = dev_net(in_dev->dev); 1722 #endif 1723 ASSERT_RTNL(); 1724 1725 #ifdef CONFIG_IP_MULTICAST 1726 timer_setup(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 0); 1727 timer_setup(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 0); 1728 in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv; 1729 #endif 1730 1731 spin_lock_init(&in_dev->mc_tomb_lock); 1732 } 1733 1734 /* Device going up */ 1735 1736 void ip_mc_up(struct in_device *in_dev) 1737 { 1738 struct ip_mc_list *pmc; 1739 #ifdef CONFIG_IP_MULTICAST 1740 struct net *net = dev_net(in_dev->dev); 1741 #endif 1742 1743 ASSERT_RTNL(); 1744 1745 #ifdef CONFIG_IP_MULTICAST 1746 in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv; 1747 #endif 1748 ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS); 1749 1750 for_each_pmc_rtnl(in_dev, pmc) { 1751 #ifdef CONFIG_IP_MULTICAST 1752 igmpv3_del_delrec(in_dev, pmc); 1753 #endif 1754 igmp_group_added(pmc); 1755 } 1756 } 1757 1758 /* 1759 * Device is about to be destroyed: clean up. 1760 */ 1761 1762 void ip_mc_destroy_dev(struct in_device *in_dev) 1763 { 1764 struct ip_mc_list *i; 1765 1766 ASSERT_RTNL(); 1767 1768 /* Deactivate timers */ 1769 ip_mc_down(in_dev); 1770 #ifdef CONFIG_IP_MULTICAST 1771 igmpv3_clear_delrec(in_dev); 1772 #endif 1773 1774 while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) { 1775 in_dev->mc_list = i->next_rcu; 1776 in_dev->mc_count--; 1777 ip_ma_put(i); 1778 } 1779 } 1780 1781 /* RTNL is locked */ 1782 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr) 1783 { 1784 struct net_device *dev = NULL; 1785 struct in_device *idev = NULL; 1786 1787 if (imr->imr_ifindex) { 1788 idev = inetdev_by_index(net, imr->imr_ifindex); 1789 return idev; 1790 } 1791 if (imr->imr_address.s_addr) { 1792 dev = __ip_dev_find(net, imr->imr_address.s_addr, false); 1793 if (!dev) 1794 return NULL; 1795 } 1796 1797 if (!dev) { 1798 struct rtable *rt = ip_route_output(net, 1799 imr->imr_multiaddr.s_addr, 1800 0, 0, 0); 1801 if (!IS_ERR(rt)) { 1802 dev = rt->dst.dev; 1803 ip_rt_put(rt); 1804 } 1805 } 1806 if (dev) { 1807 imr->imr_ifindex = dev->ifindex; 1808 idev = __in_dev_get_rtnl(dev); 1809 } 1810 return idev; 1811 } 1812 1813 /* 1814 * Join a socket to a group 1815 */ 1816 1817 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode, 1818 __be32 *psfsrc) 1819 { 1820 struct ip_sf_list *psf, *psf_prev; 1821 int rv = 0; 1822 1823 psf_prev = NULL; 1824 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1825 if (psf->sf_inaddr == *psfsrc) 1826 break; 1827 psf_prev = psf; 1828 } 1829 if (!psf || psf->sf_count[sfmode] == 0) { 1830 /* source filter not found, or count wrong => bug */ 1831 return -ESRCH; 1832 } 1833 psf->sf_count[sfmode]--; 1834 if (psf->sf_count[sfmode] == 0) { 1835 ip_rt_multicast_event(pmc->interface); 1836 } 1837 if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) { 1838 #ifdef CONFIG_IP_MULTICAST 1839 struct in_device *in_dev = pmc->interface; 1840 struct net *net = dev_net(in_dev->dev); 1841 #endif 1842 1843 /* no more filters for this source */ 1844 if (psf_prev) 1845 psf_prev->sf_next = psf->sf_next; 1846 else 1847 pmc->sources = psf->sf_next; 1848 #ifdef CONFIG_IP_MULTICAST 1849 if (psf->sf_oldin && 1850 !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) { 1851 psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1852 psf->sf_next = pmc->tomb; 1853 pmc->tomb = psf; 1854 rv = 1; 1855 } else 1856 #endif 1857 kfree(psf); 1858 } 1859 return rv; 1860 } 1861 1862 #ifndef CONFIG_IP_MULTICAST 1863 #define igmp_ifc_event(x) do { } while (0) 1864 #endif 1865 1866 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 1867 int sfcount, __be32 *psfsrc, int delta) 1868 { 1869 struct ip_mc_list *pmc; 1870 int changerec = 0; 1871 int i, err; 1872 1873 if (!in_dev) 1874 return -ENODEV; 1875 rcu_read_lock(); 1876 for_each_pmc_rcu(in_dev, pmc) { 1877 if (*pmca == pmc->multiaddr) 1878 break; 1879 } 1880 if (!pmc) { 1881 /* MCA not found?? bug */ 1882 rcu_read_unlock(); 1883 return -ESRCH; 1884 } 1885 spin_lock_bh(&pmc->lock); 1886 rcu_read_unlock(); 1887 #ifdef CONFIG_IP_MULTICAST 1888 sf_markstate(pmc); 1889 #endif 1890 if (!delta) { 1891 err = -EINVAL; 1892 if (!pmc->sfcount[sfmode]) 1893 goto out_unlock; 1894 pmc->sfcount[sfmode]--; 1895 } 1896 err = 0; 1897 for (i = 0; i < sfcount; i++) { 1898 int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]); 1899 1900 changerec |= rv > 0; 1901 if (!err && rv < 0) 1902 err = rv; 1903 } 1904 if (pmc->sfmode == MCAST_EXCLUDE && 1905 pmc->sfcount[MCAST_EXCLUDE] == 0 && 1906 pmc->sfcount[MCAST_INCLUDE]) { 1907 #ifdef CONFIG_IP_MULTICAST 1908 struct ip_sf_list *psf; 1909 struct net *net = dev_net(in_dev->dev); 1910 #endif 1911 1912 /* filter mode change */ 1913 pmc->sfmode = MCAST_INCLUDE; 1914 #ifdef CONFIG_IP_MULTICAST 1915 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1916 in_dev->mr_ifc_count = pmc->crcount; 1917 for (psf = pmc->sources; psf; psf = psf->sf_next) 1918 psf->sf_crcount = 0; 1919 igmp_ifc_event(pmc->interface); 1920 } else if (sf_setstate(pmc) || changerec) { 1921 igmp_ifc_event(pmc->interface); 1922 #endif 1923 } 1924 out_unlock: 1925 spin_unlock_bh(&pmc->lock); 1926 return err; 1927 } 1928 1929 /* 1930 * Add multicast single-source filter to the interface list 1931 */ 1932 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode, 1933 __be32 *psfsrc) 1934 { 1935 struct ip_sf_list *psf, *psf_prev; 1936 1937 psf_prev = NULL; 1938 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1939 if (psf->sf_inaddr == *psfsrc) 1940 break; 1941 psf_prev = psf; 1942 } 1943 if (!psf) { 1944 psf = kzalloc(sizeof(*psf), GFP_ATOMIC); 1945 if (!psf) 1946 return -ENOBUFS; 1947 psf->sf_inaddr = *psfsrc; 1948 if (psf_prev) { 1949 psf_prev->sf_next = psf; 1950 } else 1951 pmc->sources = psf; 1952 } 1953 psf->sf_count[sfmode]++; 1954 if (psf->sf_count[sfmode] == 1) { 1955 ip_rt_multicast_event(pmc->interface); 1956 } 1957 return 0; 1958 } 1959 1960 #ifdef CONFIG_IP_MULTICAST 1961 static void sf_markstate(struct ip_mc_list *pmc) 1962 { 1963 struct ip_sf_list *psf; 1964 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; 1965 1966 for (psf = pmc->sources; psf; psf = psf->sf_next) 1967 if (pmc->sfcount[MCAST_EXCLUDE]) { 1968 psf->sf_oldin = mca_xcount == 1969 psf->sf_count[MCAST_EXCLUDE] && 1970 !psf->sf_count[MCAST_INCLUDE]; 1971 } else 1972 psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0; 1973 } 1974 1975 static int sf_setstate(struct ip_mc_list *pmc) 1976 { 1977 struct ip_sf_list *psf, *dpsf; 1978 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; 1979 int qrv = pmc->interface->mr_qrv; 1980 int new_in, rv; 1981 1982 rv = 0; 1983 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1984 if (pmc->sfcount[MCAST_EXCLUDE]) { 1985 new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] && 1986 !psf->sf_count[MCAST_INCLUDE]; 1987 } else 1988 new_in = psf->sf_count[MCAST_INCLUDE] != 0; 1989 if (new_in) { 1990 if (!psf->sf_oldin) { 1991 struct ip_sf_list *prev = NULL; 1992 1993 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) { 1994 if (dpsf->sf_inaddr == psf->sf_inaddr) 1995 break; 1996 prev = dpsf; 1997 } 1998 if (dpsf) { 1999 if (prev) 2000 prev->sf_next = dpsf->sf_next; 2001 else 2002 pmc->tomb = dpsf->sf_next; 2003 kfree(dpsf); 2004 } 2005 psf->sf_crcount = qrv; 2006 rv++; 2007 } 2008 } else if (psf->sf_oldin) { 2009 2010 psf->sf_crcount = 0; 2011 /* 2012 * add or update "delete" records if an active filter 2013 * is now inactive 2014 */ 2015 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) 2016 if (dpsf->sf_inaddr == psf->sf_inaddr) 2017 break; 2018 if (!dpsf) { 2019 dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC); 2020 if (!dpsf) 2021 continue; 2022 *dpsf = *psf; 2023 /* pmc->lock held by callers */ 2024 dpsf->sf_next = pmc->tomb; 2025 pmc->tomb = dpsf; 2026 } 2027 dpsf->sf_crcount = qrv; 2028 rv++; 2029 } 2030 } 2031 return rv; 2032 } 2033 #endif 2034 2035 /* 2036 * Add multicast source filter list to the interface list 2037 */ 2038 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 2039 int sfcount, __be32 *psfsrc, int delta) 2040 { 2041 struct ip_mc_list *pmc; 2042 int isexclude; 2043 int i, err; 2044 2045 if (!in_dev) 2046 return -ENODEV; 2047 rcu_read_lock(); 2048 for_each_pmc_rcu(in_dev, pmc) { 2049 if (*pmca == pmc->multiaddr) 2050 break; 2051 } 2052 if (!pmc) { 2053 /* MCA not found?? bug */ 2054 rcu_read_unlock(); 2055 return -ESRCH; 2056 } 2057 spin_lock_bh(&pmc->lock); 2058 rcu_read_unlock(); 2059 2060 #ifdef CONFIG_IP_MULTICAST 2061 sf_markstate(pmc); 2062 #endif 2063 isexclude = pmc->sfmode == MCAST_EXCLUDE; 2064 if (!delta) 2065 pmc->sfcount[sfmode]++; 2066 err = 0; 2067 for (i = 0; i < sfcount; i++) { 2068 err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]); 2069 if (err) 2070 break; 2071 } 2072 if (err) { 2073 int j; 2074 2075 if (!delta) 2076 pmc->sfcount[sfmode]--; 2077 for (j = 0; j < i; j++) 2078 (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]); 2079 } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) { 2080 #ifdef CONFIG_IP_MULTICAST 2081 struct ip_sf_list *psf; 2082 struct net *net = dev_net(pmc->interface->dev); 2083 in_dev = pmc->interface; 2084 #endif 2085 2086 /* filter mode change */ 2087 if (pmc->sfcount[MCAST_EXCLUDE]) 2088 pmc->sfmode = MCAST_EXCLUDE; 2089 else if (pmc->sfcount[MCAST_INCLUDE]) 2090 pmc->sfmode = MCAST_INCLUDE; 2091 #ifdef CONFIG_IP_MULTICAST 2092 /* else no filters; keep old mode for reports */ 2093 2094 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 2095 in_dev->mr_ifc_count = pmc->crcount; 2096 for (psf = pmc->sources; psf; psf = psf->sf_next) 2097 psf->sf_crcount = 0; 2098 igmp_ifc_event(in_dev); 2099 } else if (sf_setstate(pmc)) { 2100 igmp_ifc_event(in_dev); 2101 #endif 2102 } 2103 spin_unlock_bh(&pmc->lock); 2104 return err; 2105 } 2106 2107 static void ip_mc_clear_src(struct ip_mc_list *pmc) 2108 { 2109 struct ip_sf_list *psf, *nextpsf, *tomb, *sources; 2110 2111 spin_lock_bh(&pmc->lock); 2112 tomb = pmc->tomb; 2113 pmc->tomb = NULL; 2114 sources = pmc->sources; 2115 pmc->sources = NULL; 2116 pmc->sfmode = MCAST_EXCLUDE; 2117 pmc->sfcount[MCAST_INCLUDE] = 0; 2118 pmc->sfcount[MCAST_EXCLUDE] = 1; 2119 spin_unlock_bh(&pmc->lock); 2120 2121 for (psf = tomb; psf; psf = nextpsf) { 2122 nextpsf = psf->sf_next; 2123 kfree(psf); 2124 } 2125 for (psf = sources; psf; psf = nextpsf) { 2126 nextpsf = psf->sf_next; 2127 kfree(psf); 2128 } 2129 } 2130 2131 /* Join a multicast group 2132 */ 2133 2134 int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr) 2135 { 2136 __be32 addr = imr->imr_multiaddr.s_addr; 2137 struct ip_mc_socklist *iml, *i; 2138 struct in_device *in_dev; 2139 struct inet_sock *inet = inet_sk(sk); 2140 struct net *net = sock_net(sk); 2141 int ifindex; 2142 int count = 0; 2143 int err; 2144 2145 ASSERT_RTNL(); 2146 2147 if (!ipv4_is_multicast(addr)) 2148 return -EINVAL; 2149 2150 in_dev = ip_mc_find_dev(net, imr); 2151 2152 if (!in_dev) { 2153 err = -ENODEV; 2154 goto done; 2155 } 2156 2157 err = -EADDRINUSE; 2158 ifindex = imr->imr_ifindex; 2159 for_each_pmc_rtnl(inet, i) { 2160 if (i->multi.imr_multiaddr.s_addr == addr && 2161 i->multi.imr_ifindex == ifindex) 2162 goto done; 2163 count++; 2164 } 2165 err = -ENOBUFS; 2166 if (count >= net->ipv4.sysctl_igmp_max_memberships) 2167 goto done; 2168 iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL); 2169 if (!iml) 2170 goto done; 2171 2172 memcpy(&iml->multi, imr, sizeof(*imr)); 2173 iml->next_rcu = inet->mc_list; 2174 iml->sflist = NULL; 2175 iml->sfmode = MCAST_EXCLUDE; 2176 rcu_assign_pointer(inet->mc_list, iml); 2177 ip_mc_inc_group(in_dev, addr); 2178 err = 0; 2179 done: 2180 return err; 2181 } 2182 EXPORT_SYMBOL(ip_mc_join_group); 2183 2184 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml, 2185 struct in_device *in_dev) 2186 { 2187 struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist); 2188 int err; 2189 2190 if (!psf) { 2191 /* any-source empty exclude case */ 2192 return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, 2193 iml->sfmode, 0, NULL, 0); 2194 } 2195 err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, 2196 iml->sfmode, psf->sl_count, psf->sl_addr, 0); 2197 RCU_INIT_POINTER(iml->sflist, NULL); 2198 /* decrease mem now to avoid the memleak warning */ 2199 atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc); 2200 kfree_rcu(psf, rcu); 2201 return err; 2202 } 2203 2204 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr) 2205 { 2206 struct inet_sock *inet = inet_sk(sk); 2207 struct ip_mc_socklist *iml; 2208 struct ip_mc_socklist __rcu **imlp; 2209 struct in_device *in_dev; 2210 struct net *net = sock_net(sk); 2211 __be32 group = imr->imr_multiaddr.s_addr; 2212 u32 ifindex; 2213 int ret = -EADDRNOTAVAIL; 2214 2215 ASSERT_RTNL(); 2216 2217 in_dev = ip_mc_find_dev(net, imr); 2218 if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) { 2219 ret = -ENODEV; 2220 goto out; 2221 } 2222 ifindex = imr->imr_ifindex; 2223 for (imlp = &inet->mc_list; 2224 (iml = rtnl_dereference(*imlp)) != NULL; 2225 imlp = &iml->next_rcu) { 2226 if (iml->multi.imr_multiaddr.s_addr != group) 2227 continue; 2228 if (ifindex) { 2229 if (iml->multi.imr_ifindex != ifindex) 2230 continue; 2231 } else if (imr->imr_address.s_addr && imr->imr_address.s_addr != 2232 iml->multi.imr_address.s_addr) 2233 continue; 2234 2235 (void) ip_mc_leave_src(sk, iml, in_dev); 2236 2237 *imlp = iml->next_rcu; 2238 2239 if (in_dev) 2240 ip_mc_dec_group(in_dev, group); 2241 2242 /* decrease mem now to avoid the memleak warning */ 2243 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); 2244 kfree_rcu(iml, rcu); 2245 return 0; 2246 } 2247 out: 2248 return ret; 2249 } 2250 EXPORT_SYMBOL(ip_mc_leave_group); 2251 2252 int ip_mc_source(int add, int omode, struct sock *sk, struct 2253 ip_mreq_source *mreqs, int ifindex) 2254 { 2255 int err; 2256 struct ip_mreqn imr; 2257 __be32 addr = mreqs->imr_multiaddr; 2258 struct ip_mc_socklist *pmc; 2259 struct in_device *in_dev = NULL; 2260 struct inet_sock *inet = inet_sk(sk); 2261 struct ip_sf_socklist *psl; 2262 struct net *net = sock_net(sk); 2263 int leavegroup = 0; 2264 int i, j, rv; 2265 2266 if (!ipv4_is_multicast(addr)) 2267 return -EINVAL; 2268 2269 ASSERT_RTNL(); 2270 2271 imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr; 2272 imr.imr_address.s_addr = mreqs->imr_interface; 2273 imr.imr_ifindex = ifindex; 2274 in_dev = ip_mc_find_dev(net, &imr); 2275 2276 if (!in_dev) { 2277 err = -ENODEV; 2278 goto done; 2279 } 2280 err = -EADDRNOTAVAIL; 2281 2282 for_each_pmc_rtnl(inet, pmc) { 2283 if ((pmc->multi.imr_multiaddr.s_addr == 2284 imr.imr_multiaddr.s_addr) && 2285 (pmc->multi.imr_ifindex == imr.imr_ifindex)) 2286 break; 2287 } 2288 if (!pmc) { /* must have a prior join */ 2289 err = -EINVAL; 2290 goto done; 2291 } 2292 /* if a source filter was set, must be the same mode as before */ 2293 if (pmc->sflist) { 2294 if (pmc->sfmode != omode) { 2295 err = -EINVAL; 2296 goto done; 2297 } 2298 } else if (pmc->sfmode != omode) { 2299 /* allow mode switches for empty-set filters */ 2300 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0); 2301 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0, 2302 NULL, 0); 2303 pmc->sfmode = omode; 2304 } 2305 2306 psl = rtnl_dereference(pmc->sflist); 2307 if (!add) { 2308 if (!psl) 2309 goto done; /* err = -EADDRNOTAVAIL */ 2310 rv = !0; 2311 for (i = 0; i < psl->sl_count; i++) { 2312 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr, 2313 sizeof(__be32)); 2314 if (rv == 0) 2315 break; 2316 } 2317 if (rv) /* source not found */ 2318 goto done; /* err = -EADDRNOTAVAIL */ 2319 2320 /* special case - (INCLUDE, empty) == LEAVE_GROUP */ 2321 if (psl->sl_count == 1 && omode == MCAST_INCLUDE) { 2322 leavegroup = 1; 2323 goto done; 2324 } 2325 2326 /* update the interface filter */ 2327 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1, 2328 &mreqs->imr_sourceaddr, 1); 2329 2330 for (j = i+1; j < psl->sl_count; j++) 2331 psl->sl_addr[j-1] = psl->sl_addr[j]; 2332 psl->sl_count--; 2333 err = 0; 2334 goto done; 2335 } 2336 /* else, add a new source to the filter */ 2337 2338 if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) { 2339 err = -ENOBUFS; 2340 goto done; 2341 } 2342 if (!psl || psl->sl_count == psl->sl_max) { 2343 struct ip_sf_socklist *newpsl; 2344 int count = IP_SFBLOCK; 2345 2346 if (psl) 2347 count += psl->sl_max; 2348 newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL); 2349 if (!newpsl) { 2350 err = -ENOBUFS; 2351 goto done; 2352 } 2353 newpsl->sl_max = count; 2354 newpsl->sl_count = count - IP_SFBLOCK; 2355 if (psl) { 2356 for (i = 0; i < psl->sl_count; i++) 2357 newpsl->sl_addr[i] = psl->sl_addr[i]; 2358 /* decrease mem now to avoid the memleak warning */ 2359 atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc); 2360 kfree_rcu(psl, rcu); 2361 } 2362 rcu_assign_pointer(pmc->sflist, newpsl); 2363 psl = newpsl; 2364 } 2365 rv = 1; /* > 0 for insert logic below if sl_count is 0 */ 2366 for (i = 0; i < psl->sl_count; i++) { 2367 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr, 2368 sizeof(__be32)); 2369 if (rv == 0) 2370 break; 2371 } 2372 if (rv == 0) /* address already there is an error */ 2373 goto done; 2374 for (j = psl->sl_count-1; j >= i; j--) 2375 psl->sl_addr[j+1] = psl->sl_addr[j]; 2376 psl->sl_addr[i] = mreqs->imr_sourceaddr; 2377 psl->sl_count++; 2378 err = 0; 2379 /* update the interface list */ 2380 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1, 2381 &mreqs->imr_sourceaddr, 1); 2382 done: 2383 if (leavegroup) 2384 err = ip_mc_leave_group(sk, &imr); 2385 return err; 2386 } 2387 2388 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex) 2389 { 2390 int err = 0; 2391 struct ip_mreqn imr; 2392 __be32 addr = msf->imsf_multiaddr; 2393 struct ip_mc_socklist *pmc; 2394 struct in_device *in_dev; 2395 struct inet_sock *inet = inet_sk(sk); 2396 struct ip_sf_socklist *newpsl, *psl; 2397 struct net *net = sock_net(sk); 2398 int leavegroup = 0; 2399 2400 if (!ipv4_is_multicast(addr)) 2401 return -EINVAL; 2402 if (msf->imsf_fmode != MCAST_INCLUDE && 2403 msf->imsf_fmode != MCAST_EXCLUDE) 2404 return -EINVAL; 2405 2406 ASSERT_RTNL(); 2407 2408 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; 2409 imr.imr_address.s_addr = msf->imsf_interface; 2410 imr.imr_ifindex = ifindex; 2411 in_dev = ip_mc_find_dev(net, &imr); 2412 2413 if (!in_dev) { 2414 err = -ENODEV; 2415 goto done; 2416 } 2417 2418 /* special case - (INCLUDE, empty) == LEAVE_GROUP */ 2419 if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) { 2420 leavegroup = 1; 2421 goto done; 2422 } 2423 2424 for_each_pmc_rtnl(inet, pmc) { 2425 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && 2426 pmc->multi.imr_ifindex == imr.imr_ifindex) 2427 break; 2428 } 2429 if (!pmc) { /* must have a prior join */ 2430 err = -EINVAL; 2431 goto done; 2432 } 2433 if (msf->imsf_numsrc) { 2434 newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc), 2435 GFP_KERNEL); 2436 if (!newpsl) { 2437 err = -ENOBUFS; 2438 goto done; 2439 } 2440 newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc; 2441 memcpy(newpsl->sl_addr, msf->imsf_slist, 2442 msf->imsf_numsrc * sizeof(msf->imsf_slist[0])); 2443 err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr, 2444 msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0); 2445 if (err) { 2446 sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max)); 2447 goto done; 2448 } 2449 } else { 2450 newpsl = NULL; 2451 (void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr, 2452 msf->imsf_fmode, 0, NULL, 0); 2453 } 2454 psl = rtnl_dereference(pmc->sflist); 2455 if (psl) { 2456 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, 2457 psl->sl_count, psl->sl_addr, 0); 2458 /* decrease mem now to avoid the memleak warning */ 2459 atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc); 2460 kfree_rcu(psl, rcu); 2461 } else 2462 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, 2463 0, NULL, 0); 2464 rcu_assign_pointer(pmc->sflist, newpsl); 2465 pmc->sfmode = msf->imsf_fmode; 2466 err = 0; 2467 done: 2468 if (leavegroup) 2469 err = ip_mc_leave_group(sk, &imr); 2470 return err; 2471 } 2472 2473 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf, 2474 struct ip_msfilter __user *optval, int __user *optlen) 2475 { 2476 int err, len, count, copycount; 2477 struct ip_mreqn imr; 2478 __be32 addr = msf->imsf_multiaddr; 2479 struct ip_mc_socklist *pmc; 2480 struct in_device *in_dev; 2481 struct inet_sock *inet = inet_sk(sk); 2482 struct ip_sf_socklist *psl; 2483 struct net *net = sock_net(sk); 2484 2485 ASSERT_RTNL(); 2486 2487 if (!ipv4_is_multicast(addr)) 2488 return -EINVAL; 2489 2490 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; 2491 imr.imr_address.s_addr = msf->imsf_interface; 2492 imr.imr_ifindex = 0; 2493 in_dev = ip_mc_find_dev(net, &imr); 2494 2495 if (!in_dev) { 2496 err = -ENODEV; 2497 goto done; 2498 } 2499 err = -EADDRNOTAVAIL; 2500 2501 for_each_pmc_rtnl(inet, pmc) { 2502 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && 2503 pmc->multi.imr_ifindex == imr.imr_ifindex) 2504 break; 2505 } 2506 if (!pmc) /* must have a prior join */ 2507 goto done; 2508 msf->imsf_fmode = pmc->sfmode; 2509 psl = rtnl_dereference(pmc->sflist); 2510 if (!psl) { 2511 len = 0; 2512 count = 0; 2513 } else { 2514 count = psl->sl_count; 2515 } 2516 copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc; 2517 len = copycount * sizeof(psl->sl_addr[0]); 2518 msf->imsf_numsrc = count; 2519 if (put_user(IP_MSFILTER_SIZE(copycount), optlen) || 2520 copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) { 2521 return -EFAULT; 2522 } 2523 if (len && 2524 copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len)) 2525 return -EFAULT; 2526 return 0; 2527 done: 2528 return err; 2529 } 2530 2531 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf, 2532 struct group_filter __user *optval, int __user *optlen) 2533 { 2534 int err, i, count, copycount; 2535 struct sockaddr_in *psin; 2536 __be32 addr; 2537 struct ip_mc_socklist *pmc; 2538 struct inet_sock *inet = inet_sk(sk); 2539 struct ip_sf_socklist *psl; 2540 2541 ASSERT_RTNL(); 2542 2543 psin = (struct sockaddr_in *)&gsf->gf_group; 2544 if (psin->sin_family != AF_INET) 2545 return -EINVAL; 2546 addr = psin->sin_addr.s_addr; 2547 if (!ipv4_is_multicast(addr)) 2548 return -EINVAL; 2549 2550 err = -EADDRNOTAVAIL; 2551 2552 for_each_pmc_rtnl(inet, pmc) { 2553 if (pmc->multi.imr_multiaddr.s_addr == addr && 2554 pmc->multi.imr_ifindex == gsf->gf_interface) 2555 break; 2556 } 2557 if (!pmc) /* must have a prior join */ 2558 goto done; 2559 gsf->gf_fmode = pmc->sfmode; 2560 psl = rtnl_dereference(pmc->sflist); 2561 count = psl ? psl->sl_count : 0; 2562 copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc; 2563 gsf->gf_numsrc = count; 2564 if (put_user(GROUP_FILTER_SIZE(copycount), optlen) || 2565 copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) { 2566 return -EFAULT; 2567 } 2568 for (i = 0; i < copycount; i++) { 2569 struct sockaddr_storage ss; 2570 2571 psin = (struct sockaddr_in *)&ss; 2572 memset(&ss, 0, sizeof(ss)); 2573 psin->sin_family = AF_INET; 2574 psin->sin_addr.s_addr = psl->sl_addr[i]; 2575 if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss))) 2576 return -EFAULT; 2577 } 2578 return 0; 2579 done: 2580 return err; 2581 } 2582 2583 /* 2584 * check if a multicast source filter allows delivery for a given <src,dst,intf> 2585 */ 2586 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, 2587 int dif, int sdif) 2588 { 2589 struct inet_sock *inet = inet_sk(sk); 2590 struct ip_mc_socklist *pmc; 2591 struct ip_sf_socklist *psl; 2592 int i; 2593 int ret; 2594 2595 ret = 1; 2596 if (!ipv4_is_multicast(loc_addr)) 2597 goto out; 2598 2599 rcu_read_lock(); 2600 for_each_pmc_rcu(inet, pmc) { 2601 if (pmc->multi.imr_multiaddr.s_addr == loc_addr && 2602 (pmc->multi.imr_ifindex == dif || 2603 (sdif && pmc->multi.imr_ifindex == sdif))) 2604 break; 2605 } 2606 ret = inet->mc_all; 2607 if (!pmc) 2608 goto unlock; 2609 psl = rcu_dereference(pmc->sflist); 2610 ret = (pmc->sfmode == MCAST_EXCLUDE); 2611 if (!psl) 2612 goto unlock; 2613 2614 for (i = 0; i < psl->sl_count; i++) { 2615 if (psl->sl_addr[i] == rmt_addr) 2616 break; 2617 } 2618 ret = 0; 2619 if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count) 2620 goto unlock; 2621 if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count) 2622 goto unlock; 2623 ret = 1; 2624 unlock: 2625 rcu_read_unlock(); 2626 out: 2627 return ret; 2628 } 2629 2630 /* 2631 * A socket is closing. 2632 */ 2633 2634 void ip_mc_drop_socket(struct sock *sk) 2635 { 2636 struct inet_sock *inet = inet_sk(sk); 2637 struct ip_mc_socklist *iml; 2638 struct net *net = sock_net(sk); 2639 2640 if (!inet->mc_list) 2641 return; 2642 2643 rtnl_lock(); 2644 while ((iml = rtnl_dereference(inet->mc_list)) != NULL) { 2645 struct in_device *in_dev; 2646 2647 inet->mc_list = iml->next_rcu; 2648 in_dev = inetdev_by_index(net, iml->multi.imr_ifindex); 2649 (void) ip_mc_leave_src(sk, iml, in_dev); 2650 if (in_dev) 2651 ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr); 2652 /* decrease mem now to avoid the memleak warning */ 2653 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); 2654 kfree_rcu(iml, rcu); 2655 } 2656 rtnl_unlock(); 2657 } 2658 2659 /* called with rcu_read_lock() */ 2660 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto) 2661 { 2662 struct ip_mc_list *im; 2663 struct ip_mc_list __rcu **mc_hash; 2664 struct ip_sf_list *psf; 2665 int rv = 0; 2666 2667 mc_hash = rcu_dereference(in_dev->mc_hash); 2668 if (mc_hash) { 2669 u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG); 2670 2671 for (im = rcu_dereference(mc_hash[hash]); 2672 im != NULL; 2673 im = rcu_dereference(im->next_hash)) { 2674 if (im->multiaddr == mc_addr) 2675 break; 2676 } 2677 } else { 2678 for_each_pmc_rcu(in_dev, im) { 2679 if (im->multiaddr == mc_addr) 2680 break; 2681 } 2682 } 2683 if (im && proto == IPPROTO_IGMP) { 2684 rv = 1; 2685 } else if (im) { 2686 if (src_addr) { 2687 for (psf = im->sources; psf; psf = psf->sf_next) { 2688 if (psf->sf_inaddr == src_addr) 2689 break; 2690 } 2691 if (psf) 2692 rv = psf->sf_count[MCAST_INCLUDE] || 2693 psf->sf_count[MCAST_EXCLUDE] != 2694 im->sfcount[MCAST_EXCLUDE]; 2695 else 2696 rv = im->sfcount[MCAST_EXCLUDE] != 0; 2697 } else 2698 rv = 1; /* unspecified source; tentatively allow */ 2699 } 2700 return rv; 2701 } 2702 2703 #if defined(CONFIG_PROC_FS) 2704 struct igmp_mc_iter_state { 2705 struct seq_net_private p; 2706 struct net_device *dev; 2707 struct in_device *in_dev; 2708 }; 2709 2710 #define igmp_mc_seq_private(seq) ((struct igmp_mc_iter_state *)(seq)->private) 2711 2712 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq) 2713 { 2714 struct net *net = seq_file_net(seq); 2715 struct ip_mc_list *im = NULL; 2716 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2717 2718 state->in_dev = NULL; 2719 for_each_netdev_rcu(net, state->dev) { 2720 struct in_device *in_dev; 2721 2722 in_dev = __in_dev_get_rcu(state->dev); 2723 if (!in_dev) 2724 continue; 2725 im = rcu_dereference(in_dev->mc_list); 2726 if (im) { 2727 state->in_dev = in_dev; 2728 break; 2729 } 2730 } 2731 return im; 2732 } 2733 2734 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im) 2735 { 2736 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2737 2738 im = rcu_dereference(im->next_rcu); 2739 while (!im) { 2740 state->dev = next_net_device_rcu(state->dev); 2741 if (!state->dev) { 2742 state->in_dev = NULL; 2743 break; 2744 } 2745 state->in_dev = __in_dev_get_rcu(state->dev); 2746 if (!state->in_dev) 2747 continue; 2748 im = rcu_dereference(state->in_dev->mc_list); 2749 } 2750 return im; 2751 } 2752 2753 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos) 2754 { 2755 struct ip_mc_list *im = igmp_mc_get_first(seq); 2756 if (im) 2757 while (pos && (im = igmp_mc_get_next(seq, im)) != NULL) 2758 --pos; 2759 return pos ? NULL : im; 2760 } 2761 2762 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos) 2763 __acquires(rcu) 2764 { 2765 rcu_read_lock(); 2766 return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 2767 } 2768 2769 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2770 { 2771 struct ip_mc_list *im; 2772 if (v == SEQ_START_TOKEN) 2773 im = igmp_mc_get_first(seq); 2774 else 2775 im = igmp_mc_get_next(seq, v); 2776 ++*pos; 2777 return im; 2778 } 2779 2780 static void igmp_mc_seq_stop(struct seq_file *seq, void *v) 2781 __releases(rcu) 2782 { 2783 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2784 2785 state->in_dev = NULL; 2786 state->dev = NULL; 2787 rcu_read_unlock(); 2788 } 2789 2790 static int igmp_mc_seq_show(struct seq_file *seq, void *v) 2791 { 2792 if (v == SEQ_START_TOKEN) 2793 seq_puts(seq, 2794 "Idx\tDevice : Count Querier\tGroup Users Timer\tReporter\n"); 2795 else { 2796 struct ip_mc_list *im = (struct ip_mc_list *)v; 2797 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2798 char *querier; 2799 long delta; 2800 2801 #ifdef CONFIG_IP_MULTICAST 2802 querier = IGMP_V1_SEEN(state->in_dev) ? "V1" : 2803 IGMP_V2_SEEN(state->in_dev) ? "V2" : 2804 "V3"; 2805 #else 2806 querier = "NONE"; 2807 #endif 2808 2809 if (rcu_access_pointer(state->in_dev->mc_list) == im) { 2810 seq_printf(seq, "%d\t%-10s: %5d %7s\n", 2811 state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier); 2812 } 2813 2814 delta = im->timer.expires - jiffies; 2815 seq_printf(seq, 2816 "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n", 2817 im->multiaddr, im->users, 2818 im->tm_running, 2819 im->tm_running ? jiffies_delta_to_clock_t(delta) : 0, 2820 im->reporter); 2821 } 2822 return 0; 2823 } 2824 2825 static const struct seq_operations igmp_mc_seq_ops = { 2826 .start = igmp_mc_seq_start, 2827 .next = igmp_mc_seq_next, 2828 .stop = igmp_mc_seq_stop, 2829 .show = igmp_mc_seq_show, 2830 }; 2831 2832 struct igmp_mcf_iter_state { 2833 struct seq_net_private p; 2834 struct net_device *dev; 2835 struct in_device *idev; 2836 struct ip_mc_list *im; 2837 }; 2838 2839 #define igmp_mcf_seq_private(seq) ((struct igmp_mcf_iter_state *)(seq)->private) 2840 2841 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq) 2842 { 2843 struct net *net = seq_file_net(seq); 2844 struct ip_sf_list *psf = NULL; 2845 struct ip_mc_list *im = NULL; 2846 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2847 2848 state->idev = NULL; 2849 state->im = NULL; 2850 for_each_netdev_rcu(net, state->dev) { 2851 struct in_device *idev; 2852 idev = __in_dev_get_rcu(state->dev); 2853 if (unlikely(!idev)) 2854 continue; 2855 im = rcu_dereference(idev->mc_list); 2856 if (likely(im)) { 2857 spin_lock_bh(&im->lock); 2858 psf = im->sources; 2859 if (likely(psf)) { 2860 state->im = im; 2861 state->idev = idev; 2862 break; 2863 } 2864 spin_unlock_bh(&im->lock); 2865 } 2866 } 2867 return psf; 2868 } 2869 2870 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf) 2871 { 2872 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2873 2874 psf = psf->sf_next; 2875 while (!psf) { 2876 spin_unlock_bh(&state->im->lock); 2877 state->im = state->im->next; 2878 while (!state->im) { 2879 state->dev = next_net_device_rcu(state->dev); 2880 if (!state->dev) { 2881 state->idev = NULL; 2882 goto out; 2883 } 2884 state->idev = __in_dev_get_rcu(state->dev); 2885 if (!state->idev) 2886 continue; 2887 state->im = rcu_dereference(state->idev->mc_list); 2888 } 2889 if (!state->im) 2890 break; 2891 spin_lock_bh(&state->im->lock); 2892 psf = state->im->sources; 2893 } 2894 out: 2895 return psf; 2896 } 2897 2898 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos) 2899 { 2900 struct ip_sf_list *psf = igmp_mcf_get_first(seq); 2901 if (psf) 2902 while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL) 2903 --pos; 2904 return pos ? NULL : psf; 2905 } 2906 2907 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos) 2908 __acquires(rcu) 2909 { 2910 rcu_read_lock(); 2911 return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 2912 } 2913 2914 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2915 { 2916 struct ip_sf_list *psf; 2917 if (v == SEQ_START_TOKEN) 2918 psf = igmp_mcf_get_first(seq); 2919 else 2920 psf = igmp_mcf_get_next(seq, v); 2921 ++*pos; 2922 return psf; 2923 } 2924 2925 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v) 2926 __releases(rcu) 2927 { 2928 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2929 if (likely(state->im)) { 2930 spin_unlock_bh(&state->im->lock); 2931 state->im = NULL; 2932 } 2933 state->idev = NULL; 2934 state->dev = NULL; 2935 rcu_read_unlock(); 2936 } 2937 2938 static int igmp_mcf_seq_show(struct seq_file *seq, void *v) 2939 { 2940 struct ip_sf_list *psf = (struct ip_sf_list *)v; 2941 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2942 2943 if (v == SEQ_START_TOKEN) { 2944 seq_puts(seq, "Idx Device MCA SRC INC EXC\n"); 2945 } else { 2946 seq_printf(seq, 2947 "%3d %6.6s 0x%08x " 2948 "0x%08x %6lu %6lu\n", 2949 state->dev->ifindex, state->dev->name, 2950 ntohl(state->im->multiaddr), 2951 ntohl(psf->sf_inaddr), 2952 psf->sf_count[MCAST_INCLUDE], 2953 psf->sf_count[MCAST_EXCLUDE]); 2954 } 2955 return 0; 2956 } 2957 2958 static const struct seq_operations igmp_mcf_seq_ops = { 2959 .start = igmp_mcf_seq_start, 2960 .next = igmp_mcf_seq_next, 2961 .stop = igmp_mcf_seq_stop, 2962 .show = igmp_mcf_seq_show, 2963 }; 2964 2965 static int __net_init igmp_net_init(struct net *net) 2966 { 2967 struct proc_dir_entry *pde; 2968 int err; 2969 2970 pde = proc_create_net("igmp", 0444, net->proc_net, &igmp_mc_seq_ops, 2971 sizeof(struct igmp_mc_iter_state)); 2972 if (!pde) 2973 goto out_igmp; 2974 pde = proc_create_net("mcfilter", 0444, net->proc_net, 2975 &igmp_mcf_seq_ops, sizeof(struct igmp_mcf_iter_state)); 2976 if (!pde) 2977 goto out_mcfilter; 2978 err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET, 2979 SOCK_DGRAM, 0, net); 2980 if (err < 0) { 2981 pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n", 2982 err); 2983 goto out_sock; 2984 } 2985 2986 return 0; 2987 2988 out_sock: 2989 remove_proc_entry("mcfilter", net->proc_net); 2990 out_mcfilter: 2991 remove_proc_entry("igmp", net->proc_net); 2992 out_igmp: 2993 return -ENOMEM; 2994 } 2995 2996 static void __net_exit igmp_net_exit(struct net *net) 2997 { 2998 remove_proc_entry("mcfilter", net->proc_net); 2999 remove_proc_entry("igmp", net->proc_net); 3000 inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk); 3001 } 3002 3003 static struct pernet_operations igmp_net_ops = { 3004 .init = igmp_net_init, 3005 .exit = igmp_net_exit, 3006 }; 3007 #endif 3008 3009 static int igmp_netdev_event(struct notifier_block *this, 3010 unsigned long event, void *ptr) 3011 { 3012 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 3013 struct in_device *in_dev; 3014 3015 switch (event) { 3016 case NETDEV_RESEND_IGMP: 3017 in_dev = __in_dev_get_rtnl(dev); 3018 if (in_dev) 3019 ip_mc_rejoin_groups(in_dev); 3020 break; 3021 default: 3022 break; 3023 } 3024 return NOTIFY_DONE; 3025 } 3026 3027 static struct notifier_block igmp_notifier = { 3028 .notifier_call = igmp_netdev_event, 3029 }; 3030 3031 int __init igmp_mc_init(void) 3032 { 3033 #if defined(CONFIG_PROC_FS) 3034 int err; 3035 3036 err = register_pernet_subsys(&igmp_net_ops); 3037 if (err) 3038 return err; 3039 err = register_netdevice_notifier(&igmp_notifier); 3040 if (err) 3041 goto reg_notif_fail; 3042 return 0; 3043 3044 reg_notif_fail: 3045 unregister_pernet_subsys(&igmp_net_ops); 3046 return err; 3047 #else 3048 return register_netdevice_notifier(&igmp_notifier); 3049 #endif 3050 } 3051