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 (inet_ifa_match(fl4->saddr, ifa)) 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 pip->saddr = igmpv3_get_srcaddr(dev, &fl4); 390 pip->protocol = IPPROTO_IGMP; 391 pip->tot_len = 0; /* filled in later */ 392 ip_select_ident(net, skb, NULL); 393 ((u8 *)&pip[1])[0] = IPOPT_RA; 394 ((u8 *)&pip[1])[1] = 4; 395 ((u8 *)&pip[1])[2] = 0; 396 ((u8 *)&pip[1])[3] = 0; 397 398 skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4; 399 skb_put(skb, sizeof(*pig)); 400 pig = igmpv3_report_hdr(skb); 401 pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT; 402 pig->resv1 = 0; 403 pig->csum = 0; 404 pig->resv2 = 0; 405 pig->ngrec = 0; 406 return skb; 407 } 408 409 static int igmpv3_sendpack(struct sk_buff *skb) 410 { 411 struct igmphdr *pig = igmp_hdr(skb); 412 const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb); 413 414 pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen); 415 416 return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb); 417 } 418 419 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel) 420 { 421 return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel); 422 } 423 424 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc, 425 int type, struct igmpv3_grec **ppgr, unsigned int mtu) 426 { 427 struct net_device *dev = pmc->interface->dev; 428 struct igmpv3_report *pih; 429 struct igmpv3_grec *pgr; 430 431 if (!skb) { 432 skb = igmpv3_newpack(dev, mtu); 433 if (!skb) 434 return NULL; 435 } 436 pgr = skb_put(skb, sizeof(struct igmpv3_grec)); 437 pgr->grec_type = type; 438 pgr->grec_auxwords = 0; 439 pgr->grec_nsrcs = 0; 440 pgr->grec_mca = pmc->multiaddr; 441 pih = igmpv3_report_hdr(skb); 442 pih->ngrec = htons(ntohs(pih->ngrec)+1); 443 *ppgr = pgr; 444 return skb; 445 } 446 447 #define AVAILABLE(skb) ((skb) ? skb_availroom(skb) : 0) 448 449 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc, 450 int type, int gdeleted, int sdeleted) 451 { 452 struct net_device *dev = pmc->interface->dev; 453 struct net *net = dev_net(dev); 454 struct igmpv3_report *pih; 455 struct igmpv3_grec *pgr = NULL; 456 struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list; 457 int scount, stotal, first, isquery, truncate; 458 unsigned int mtu; 459 460 if (pmc->multiaddr == IGMP_ALL_HOSTS) 461 return skb; 462 if (ipv4_is_local_multicast(pmc->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports) 463 return skb; 464 465 mtu = READ_ONCE(dev->mtu); 466 if (mtu < IPV4_MIN_MTU) 467 return skb; 468 469 isquery = type == IGMPV3_MODE_IS_INCLUDE || 470 type == IGMPV3_MODE_IS_EXCLUDE; 471 truncate = type == IGMPV3_MODE_IS_EXCLUDE || 472 type == IGMPV3_CHANGE_TO_EXCLUDE; 473 474 stotal = scount = 0; 475 476 psf_list = sdeleted ? &pmc->tomb : &pmc->sources; 477 478 if (!*psf_list) 479 goto empty_source; 480 481 pih = skb ? igmpv3_report_hdr(skb) : NULL; 482 483 /* EX and TO_EX get a fresh packet, if needed */ 484 if (truncate) { 485 if (pih && pih->ngrec && 486 AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) { 487 if (skb) 488 igmpv3_sendpack(skb); 489 skb = igmpv3_newpack(dev, mtu); 490 } 491 } 492 first = 1; 493 psf_prev = NULL; 494 for (psf = *psf_list; psf; psf = psf_next) { 495 __be32 *psrc; 496 497 psf_next = psf->sf_next; 498 499 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) { 500 psf_prev = psf; 501 continue; 502 } 503 504 /* Based on RFC3376 5.1. Should not send source-list change 505 * records when there is a filter mode change. 506 */ 507 if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) || 508 (!gdeleted && pmc->crcount)) && 509 (type == IGMPV3_ALLOW_NEW_SOURCES || 510 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) 511 goto decrease_sf_crcount; 512 513 /* clear marks on query responses */ 514 if (isquery) 515 psf->sf_gsresp = 0; 516 517 if (AVAILABLE(skb) < sizeof(__be32) + 518 first*sizeof(struct igmpv3_grec)) { 519 if (truncate && !first) 520 break; /* truncate these */ 521 if (pgr) 522 pgr->grec_nsrcs = htons(scount); 523 if (skb) 524 igmpv3_sendpack(skb); 525 skb = igmpv3_newpack(dev, mtu); 526 first = 1; 527 scount = 0; 528 } 529 if (first) { 530 skb = add_grhead(skb, pmc, type, &pgr, mtu); 531 first = 0; 532 } 533 if (!skb) 534 return NULL; 535 psrc = skb_put(skb, sizeof(__be32)); 536 *psrc = psf->sf_inaddr; 537 scount++; stotal++; 538 if ((type == IGMPV3_ALLOW_NEW_SOURCES || 539 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) { 540 decrease_sf_crcount: 541 psf->sf_crcount--; 542 if ((sdeleted || gdeleted) && psf->sf_crcount == 0) { 543 if (psf_prev) 544 psf_prev->sf_next = psf->sf_next; 545 else 546 *psf_list = psf->sf_next; 547 kfree(psf); 548 continue; 549 } 550 } 551 psf_prev = psf; 552 } 553 554 empty_source: 555 if (!stotal) { 556 if (type == IGMPV3_ALLOW_NEW_SOURCES || 557 type == IGMPV3_BLOCK_OLD_SOURCES) 558 return skb; 559 if (pmc->crcount || isquery) { 560 /* make sure we have room for group header */ 561 if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) { 562 igmpv3_sendpack(skb); 563 skb = NULL; /* add_grhead will get a new one */ 564 } 565 skb = add_grhead(skb, pmc, type, &pgr, mtu); 566 } 567 } 568 if (pgr) 569 pgr->grec_nsrcs = htons(scount); 570 571 if (isquery) 572 pmc->gsquery = 0; /* clear query state on report */ 573 return skb; 574 } 575 576 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc) 577 { 578 struct sk_buff *skb = NULL; 579 struct net *net = dev_net(in_dev->dev); 580 int type; 581 582 if (!pmc) { 583 rcu_read_lock(); 584 for_each_pmc_rcu(in_dev, pmc) { 585 if (pmc->multiaddr == IGMP_ALL_HOSTS) 586 continue; 587 if (ipv4_is_local_multicast(pmc->multiaddr) && 588 !net->ipv4.sysctl_igmp_llm_reports) 589 continue; 590 spin_lock_bh(&pmc->lock); 591 if (pmc->sfcount[MCAST_EXCLUDE]) 592 type = IGMPV3_MODE_IS_EXCLUDE; 593 else 594 type = IGMPV3_MODE_IS_INCLUDE; 595 skb = add_grec(skb, pmc, type, 0, 0); 596 spin_unlock_bh(&pmc->lock); 597 } 598 rcu_read_unlock(); 599 } else { 600 spin_lock_bh(&pmc->lock); 601 if (pmc->sfcount[MCAST_EXCLUDE]) 602 type = IGMPV3_MODE_IS_EXCLUDE; 603 else 604 type = IGMPV3_MODE_IS_INCLUDE; 605 skb = add_grec(skb, pmc, type, 0, 0); 606 spin_unlock_bh(&pmc->lock); 607 } 608 if (!skb) 609 return 0; 610 return igmpv3_sendpack(skb); 611 } 612 613 /* 614 * remove zero-count source records from a source filter list 615 */ 616 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf) 617 { 618 struct ip_sf_list *psf_prev, *psf_next, *psf; 619 620 psf_prev = NULL; 621 for (psf = *ppsf; psf; psf = psf_next) { 622 psf_next = psf->sf_next; 623 if (psf->sf_crcount == 0) { 624 if (psf_prev) 625 psf_prev->sf_next = psf->sf_next; 626 else 627 *ppsf = psf->sf_next; 628 kfree(psf); 629 } else 630 psf_prev = psf; 631 } 632 } 633 634 static void igmpv3_send_cr(struct in_device *in_dev) 635 { 636 struct ip_mc_list *pmc, *pmc_prev, *pmc_next; 637 struct sk_buff *skb = NULL; 638 int type, dtype; 639 640 rcu_read_lock(); 641 spin_lock_bh(&in_dev->mc_tomb_lock); 642 643 /* deleted MCA's */ 644 pmc_prev = NULL; 645 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) { 646 pmc_next = pmc->next; 647 if (pmc->sfmode == MCAST_INCLUDE) { 648 type = IGMPV3_BLOCK_OLD_SOURCES; 649 dtype = IGMPV3_BLOCK_OLD_SOURCES; 650 skb = add_grec(skb, pmc, type, 1, 0); 651 skb = add_grec(skb, pmc, dtype, 1, 1); 652 } 653 if (pmc->crcount) { 654 if (pmc->sfmode == MCAST_EXCLUDE) { 655 type = IGMPV3_CHANGE_TO_INCLUDE; 656 skb = add_grec(skb, pmc, type, 1, 0); 657 } 658 pmc->crcount--; 659 if (pmc->crcount == 0) { 660 igmpv3_clear_zeros(&pmc->tomb); 661 igmpv3_clear_zeros(&pmc->sources); 662 } 663 } 664 if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) { 665 if (pmc_prev) 666 pmc_prev->next = pmc_next; 667 else 668 in_dev->mc_tomb = pmc_next; 669 in_dev_put(pmc->interface); 670 kfree(pmc); 671 } else 672 pmc_prev = pmc; 673 } 674 spin_unlock_bh(&in_dev->mc_tomb_lock); 675 676 /* change recs */ 677 for_each_pmc_rcu(in_dev, pmc) { 678 spin_lock_bh(&pmc->lock); 679 if (pmc->sfcount[MCAST_EXCLUDE]) { 680 type = IGMPV3_BLOCK_OLD_SOURCES; 681 dtype = IGMPV3_ALLOW_NEW_SOURCES; 682 } else { 683 type = IGMPV3_ALLOW_NEW_SOURCES; 684 dtype = IGMPV3_BLOCK_OLD_SOURCES; 685 } 686 skb = add_grec(skb, pmc, type, 0, 0); 687 skb = add_grec(skb, pmc, dtype, 0, 1); /* deleted sources */ 688 689 /* filter mode changes */ 690 if (pmc->crcount) { 691 if (pmc->sfmode == MCAST_EXCLUDE) 692 type = IGMPV3_CHANGE_TO_EXCLUDE; 693 else 694 type = IGMPV3_CHANGE_TO_INCLUDE; 695 skb = add_grec(skb, pmc, type, 0, 0); 696 pmc->crcount--; 697 } 698 spin_unlock_bh(&pmc->lock); 699 } 700 rcu_read_unlock(); 701 702 if (!skb) 703 return; 704 (void) igmpv3_sendpack(skb); 705 } 706 707 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc, 708 int type) 709 { 710 struct sk_buff *skb; 711 struct iphdr *iph; 712 struct igmphdr *ih; 713 struct rtable *rt; 714 struct net_device *dev = in_dev->dev; 715 struct net *net = dev_net(dev); 716 __be32 group = pmc ? pmc->multiaddr : 0; 717 struct flowi4 fl4; 718 __be32 dst; 719 int hlen, tlen; 720 721 if (type == IGMPV3_HOST_MEMBERSHIP_REPORT) 722 return igmpv3_send_report(in_dev, pmc); 723 724 if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports) 725 return 0; 726 727 if (type == IGMP_HOST_LEAVE_MESSAGE) 728 dst = IGMP_ALL_ROUTER; 729 else 730 dst = group; 731 732 rt = ip_route_output_ports(net, &fl4, NULL, dst, 0, 733 0, 0, 734 IPPROTO_IGMP, 0, dev->ifindex); 735 if (IS_ERR(rt)) 736 return -1; 737 738 hlen = LL_RESERVED_SPACE(dev); 739 tlen = dev->needed_tailroom; 740 skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC); 741 if (!skb) { 742 ip_rt_put(rt); 743 return -1; 744 } 745 skb->priority = TC_PRIO_CONTROL; 746 747 skb_dst_set(skb, &rt->dst); 748 749 skb_reserve(skb, hlen); 750 751 skb_reset_network_header(skb); 752 iph = ip_hdr(skb); 753 skb_put(skb, sizeof(struct iphdr) + 4); 754 755 iph->version = 4; 756 iph->ihl = (sizeof(struct iphdr)+4)>>2; 757 iph->tos = 0xc0; 758 iph->frag_off = htons(IP_DF); 759 iph->ttl = 1; 760 iph->daddr = dst; 761 iph->saddr = fl4.saddr; 762 iph->protocol = IPPROTO_IGMP; 763 ip_select_ident(net, skb, NULL); 764 ((u8 *)&iph[1])[0] = IPOPT_RA; 765 ((u8 *)&iph[1])[1] = 4; 766 ((u8 *)&iph[1])[2] = 0; 767 ((u8 *)&iph[1])[3] = 0; 768 769 ih = skb_put(skb, sizeof(struct igmphdr)); 770 ih->type = type; 771 ih->code = 0; 772 ih->csum = 0; 773 ih->group = group; 774 ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr)); 775 776 return ip_local_out(net, skb->sk, skb); 777 } 778 779 static void igmp_gq_timer_expire(struct timer_list *t) 780 { 781 struct in_device *in_dev = from_timer(in_dev, t, mr_gq_timer); 782 783 in_dev->mr_gq_running = 0; 784 igmpv3_send_report(in_dev, NULL); 785 in_dev_put(in_dev); 786 } 787 788 static void igmp_ifc_timer_expire(struct timer_list *t) 789 { 790 struct in_device *in_dev = from_timer(in_dev, t, mr_ifc_timer); 791 792 igmpv3_send_cr(in_dev); 793 if (in_dev->mr_ifc_count) { 794 in_dev->mr_ifc_count--; 795 igmp_ifc_start_timer(in_dev, 796 unsolicited_report_interval(in_dev)); 797 } 798 in_dev_put(in_dev); 799 } 800 801 static void igmp_ifc_event(struct in_device *in_dev) 802 { 803 struct net *net = dev_net(in_dev->dev); 804 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) 805 return; 806 in_dev->mr_ifc_count = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 807 igmp_ifc_start_timer(in_dev, 1); 808 } 809 810 811 static void igmp_timer_expire(struct timer_list *t) 812 { 813 struct ip_mc_list *im = from_timer(im, t, timer); 814 struct in_device *in_dev = im->interface; 815 816 spin_lock(&im->lock); 817 im->tm_running = 0; 818 819 if (im->unsolicit_count) { 820 im->unsolicit_count--; 821 igmp_start_timer(im, unsolicited_report_interval(in_dev)); 822 } 823 im->reporter = 1; 824 spin_unlock(&im->lock); 825 826 if (IGMP_V1_SEEN(in_dev)) 827 igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT); 828 else if (IGMP_V2_SEEN(in_dev)) 829 igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT); 830 else 831 igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT); 832 833 ip_ma_put(im); 834 } 835 836 /* mark EXCLUDE-mode sources */ 837 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs) 838 { 839 struct ip_sf_list *psf; 840 int i, scount; 841 842 scount = 0; 843 for (psf = pmc->sources; psf; psf = psf->sf_next) { 844 if (scount == nsrcs) 845 break; 846 for (i = 0; i < nsrcs; i++) { 847 /* skip inactive filters */ 848 if (psf->sf_count[MCAST_INCLUDE] || 849 pmc->sfcount[MCAST_EXCLUDE] != 850 psf->sf_count[MCAST_EXCLUDE]) 851 break; 852 if (srcs[i] == psf->sf_inaddr) { 853 scount++; 854 break; 855 } 856 } 857 } 858 pmc->gsquery = 0; 859 if (scount == nsrcs) /* all sources excluded */ 860 return 0; 861 return 1; 862 } 863 864 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs) 865 { 866 struct ip_sf_list *psf; 867 int i, scount; 868 869 if (pmc->sfmode == MCAST_EXCLUDE) 870 return igmp_xmarksources(pmc, nsrcs, srcs); 871 872 /* mark INCLUDE-mode sources */ 873 scount = 0; 874 for (psf = pmc->sources; psf; psf = psf->sf_next) { 875 if (scount == nsrcs) 876 break; 877 for (i = 0; i < nsrcs; i++) 878 if (srcs[i] == psf->sf_inaddr) { 879 psf->sf_gsresp = 1; 880 scount++; 881 break; 882 } 883 } 884 if (!scount) { 885 pmc->gsquery = 0; 886 return 0; 887 } 888 pmc->gsquery = 1; 889 return 1; 890 } 891 892 /* return true if packet was dropped */ 893 static bool igmp_heard_report(struct in_device *in_dev, __be32 group) 894 { 895 struct ip_mc_list *im; 896 struct net *net = dev_net(in_dev->dev); 897 898 /* Timers are only set for non-local groups */ 899 900 if (group == IGMP_ALL_HOSTS) 901 return false; 902 if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports) 903 return false; 904 905 rcu_read_lock(); 906 for_each_pmc_rcu(in_dev, im) { 907 if (im->multiaddr == group) { 908 igmp_stop_timer(im); 909 break; 910 } 911 } 912 rcu_read_unlock(); 913 return false; 914 } 915 916 /* return true if packet was dropped */ 917 static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb, 918 int len) 919 { 920 struct igmphdr *ih = igmp_hdr(skb); 921 struct igmpv3_query *ih3 = igmpv3_query_hdr(skb); 922 struct ip_mc_list *im; 923 __be32 group = ih->group; 924 int max_delay; 925 int mark = 0; 926 struct net *net = dev_net(in_dev->dev); 927 928 929 if (len == 8) { 930 if (ih->code == 0) { 931 /* Alas, old v1 router presents here. */ 932 933 max_delay = IGMP_QUERY_RESPONSE_INTERVAL; 934 in_dev->mr_v1_seen = jiffies + 935 IGMP_V1_ROUTER_PRESENT_TIMEOUT; 936 group = 0; 937 } else { 938 /* v2 router present */ 939 max_delay = ih->code*(HZ/IGMP_TIMER_SCALE); 940 in_dev->mr_v2_seen = jiffies + 941 IGMP_V2_ROUTER_PRESENT_TIMEOUT; 942 } 943 /* cancel the interface change timer */ 944 in_dev->mr_ifc_count = 0; 945 if (del_timer(&in_dev->mr_ifc_timer)) 946 __in_dev_put(in_dev); 947 /* clear deleted report items */ 948 igmpv3_clear_delrec(in_dev); 949 } else if (len < 12) { 950 return true; /* ignore bogus packet; freed by caller */ 951 } else if (IGMP_V1_SEEN(in_dev)) { 952 /* This is a v3 query with v1 queriers present */ 953 max_delay = IGMP_QUERY_RESPONSE_INTERVAL; 954 group = 0; 955 } else if (IGMP_V2_SEEN(in_dev)) { 956 /* this is a v3 query with v2 queriers present; 957 * Interpretation of the max_delay code is problematic here. 958 * A real v2 host would use ih_code directly, while v3 has a 959 * different encoding. We use the v3 encoding as more likely 960 * to be intended in a v3 query. 961 */ 962 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE); 963 if (!max_delay) 964 max_delay = 1; /* can't mod w/ 0 */ 965 } else { /* v3 */ 966 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) 967 return true; 968 969 ih3 = igmpv3_query_hdr(skb); 970 if (ih3->nsrcs) { 971 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query) 972 + ntohs(ih3->nsrcs)*sizeof(__be32))) 973 return true; 974 ih3 = igmpv3_query_hdr(skb); 975 } 976 977 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE); 978 if (!max_delay) 979 max_delay = 1; /* can't mod w/ 0 */ 980 in_dev->mr_maxdelay = max_delay; 981 if (ih3->qrv) 982 in_dev->mr_qrv = ih3->qrv; 983 if (!group) { /* general query */ 984 if (ih3->nsrcs) 985 return true; /* no sources allowed */ 986 igmp_gq_start_timer(in_dev); 987 return false; 988 } 989 /* mark sources to include, if group & source-specific */ 990 mark = ih3->nsrcs != 0; 991 } 992 993 /* 994 * - Start the timers in all of our membership records 995 * that the query applies to for the interface on 996 * which the query arrived excl. those that belong 997 * to a "local" group (224.0.0.X) 998 * - For timers already running check if they need to 999 * be reset. 1000 * - Use the igmp->igmp_code field as the maximum 1001 * delay possible 1002 */ 1003 rcu_read_lock(); 1004 for_each_pmc_rcu(in_dev, im) { 1005 int changed; 1006 1007 if (group && group != im->multiaddr) 1008 continue; 1009 if (im->multiaddr == IGMP_ALL_HOSTS) 1010 continue; 1011 if (ipv4_is_local_multicast(im->multiaddr) && 1012 !net->ipv4.sysctl_igmp_llm_reports) 1013 continue; 1014 spin_lock_bh(&im->lock); 1015 if (im->tm_running) 1016 im->gsquery = im->gsquery && mark; 1017 else 1018 im->gsquery = mark; 1019 changed = !im->gsquery || 1020 igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs); 1021 spin_unlock_bh(&im->lock); 1022 if (changed) 1023 igmp_mod_timer(im, max_delay); 1024 } 1025 rcu_read_unlock(); 1026 return false; 1027 } 1028 1029 /* called in rcu_read_lock() section */ 1030 int igmp_rcv(struct sk_buff *skb) 1031 { 1032 /* This basically follows the spec line by line -- see RFC1112 */ 1033 struct igmphdr *ih; 1034 struct net_device *dev = skb->dev; 1035 struct in_device *in_dev; 1036 int len = skb->len; 1037 bool dropped = true; 1038 1039 if (netif_is_l3_master(dev)) { 1040 dev = dev_get_by_index_rcu(dev_net(dev), IPCB(skb)->iif); 1041 if (!dev) 1042 goto drop; 1043 } 1044 1045 in_dev = __in_dev_get_rcu(dev); 1046 if (!in_dev) 1047 goto drop; 1048 1049 if (!pskb_may_pull(skb, sizeof(struct igmphdr))) 1050 goto drop; 1051 1052 if (skb_checksum_simple_validate(skb)) 1053 goto drop; 1054 1055 ih = igmp_hdr(skb); 1056 switch (ih->type) { 1057 case IGMP_HOST_MEMBERSHIP_QUERY: 1058 dropped = igmp_heard_query(in_dev, skb, len); 1059 break; 1060 case IGMP_HOST_MEMBERSHIP_REPORT: 1061 case IGMPV2_HOST_MEMBERSHIP_REPORT: 1062 /* Is it our report looped back? */ 1063 if (rt_is_output_route(skb_rtable(skb))) 1064 break; 1065 /* don't rely on MC router hearing unicast reports */ 1066 if (skb->pkt_type == PACKET_MULTICAST || 1067 skb->pkt_type == PACKET_BROADCAST) 1068 dropped = igmp_heard_report(in_dev, ih->group); 1069 break; 1070 case IGMP_PIM: 1071 #ifdef CONFIG_IP_PIMSM_V1 1072 return pim_rcv_v1(skb); 1073 #endif 1074 case IGMPV3_HOST_MEMBERSHIP_REPORT: 1075 case IGMP_DVMRP: 1076 case IGMP_TRACE: 1077 case IGMP_HOST_LEAVE_MESSAGE: 1078 case IGMP_MTRACE: 1079 case IGMP_MTRACE_RESP: 1080 break; 1081 default: 1082 break; 1083 } 1084 1085 drop: 1086 if (dropped) 1087 kfree_skb(skb); 1088 else 1089 consume_skb(skb); 1090 return 0; 1091 } 1092 1093 #endif 1094 1095 1096 /* 1097 * Add a filter to a device 1098 */ 1099 1100 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr) 1101 { 1102 char buf[MAX_ADDR_LEN]; 1103 struct net_device *dev = in_dev->dev; 1104 1105 /* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG. 1106 We will get multicast token leakage, when IFF_MULTICAST 1107 is changed. This check should be done in ndo_set_rx_mode 1108 routine. Something sort of: 1109 if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; } 1110 --ANK 1111 */ 1112 if (arp_mc_map(addr, buf, dev, 0) == 0) 1113 dev_mc_add(dev, buf); 1114 } 1115 1116 /* 1117 * Remove a filter from a device 1118 */ 1119 1120 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr) 1121 { 1122 char buf[MAX_ADDR_LEN]; 1123 struct net_device *dev = in_dev->dev; 1124 1125 if (arp_mc_map(addr, buf, dev, 0) == 0) 1126 dev_mc_del(dev, buf); 1127 } 1128 1129 #ifdef CONFIG_IP_MULTICAST 1130 /* 1131 * deleted ip_mc_list manipulation 1132 */ 1133 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im) 1134 { 1135 struct ip_mc_list *pmc; 1136 struct net *net = dev_net(in_dev->dev); 1137 1138 /* this is an "ip_mc_list" for convenience; only the fields below 1139 * are actually used. In particular, the refcnt and users are not 1140 * used for management of the delete list. Using the same structure 1141 * for deleted items allows change reports to use common code with 1142 * non-deleted or query-response MCA's. 1143 */ 1144 pmc = kzalloc(sizeof(*pmc), GFP_KERNEL); 1145 if (!pmc) 1146 return; 1147 spin_lock_init(&pmc->lock); 1148 spin_lock_bh(&im->lock); 1149 pmc->interface = im->interface; 1150 in_dev_hold(in_dev); 1151 pmc->multiaddr = im->multiaddr; 1152 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1153 pmc->sfmode = im->sfmode; 1154 if (pmc->sfmode == MCAST_INCLUDE) { 1155 struct ip_sf_list *psf; 1156 1157 pmc->tomb = im->tomb; 1158 pmc->sources = im->sources; 1159 im->tomb = im->sources = NULL; 1160 for (psf = pmc->sources; psf; psf = psf->sf_next) 1161 psf->sf_crcount = pmc->crcount; 1162 } 1163 spin_unlock_bh(&im->lock); 1164 1165 spin_lock_bh(&in_dev->mc_tomb_lock); 1166 pmc->next = in_dev->mc_tomb; 1167 in_dev->mc_tomb = pmc; 1168 spin_unlock_bh(&in_dev->mc_tomb_lock); 1169 } 1170 1171 /* 1172 * restore ip_mc_list deleted records 1173 */ 1174 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im) 1175 { 1176 struct ip_mc_list *pmc, *pmc_prev; 1177 struct ip_sf_list *psf; 1178 struct net *net = dev_net(in_dev->dev); 1179 __be32 multiaddr = im->multiaddr; 1180 1181 spin_lock_bh(&in_dev->mc_tomb_lock); 1182 pmc_prev = NULL; 1183 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) { 1184 if (pmc->multiaddr == multiaddr) 1185 break; 1186 pmc_prev = pmc; 1187 } 1188 if (pmc) { 1189 if (pmc_prev) 1190 pmc_prev->next = pmc->next; 1191 else 1192 in_dev->mc_tomb = pmc->next; 1193 } 1194 spin_unlock_bh(&in_dev->mc_tomb_lock); 1195 1196 spin_lock_bh(&im->lock); 1197 if (pmc) { 1198 im->interface = pmc->interface; 1199 im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1200 im->sfmode = pmc->sfmode; 1201 if (pmc->sfmode == MCAST_INCLUDE) { 1202 im->tomb = pmc->tomb; 1203 im->sources = pmc->sources; 1204 for (psf = im->sources; psf; psf = psf->sf_next) 1205 psf->sf_crcount = im->crcount; 1206 } 1207 in_dev_put(pmc->interface); 1208 kfree(pmc); 1209 } 1210 spin_unlock_bh(&im->lock); 1211 } 1212 1213 /* 1214 * flush ip_mc_list deleted records 1215 */ 1216 static void igmpv3_clear_delrec(struct in_device *in_dev) 1217 { 1218 struct ip_mc_list *pmc, *nextpmc; 1219 1220 spin_lock_bh(&in_dev->mc_tomb_lock); 1221 pmc = in_dev->mc_tomb; 1222 in_dev->mc_tomb = NULL; 1223 spin_unlock_bh(&in_dev->mc_tomb_lock); 1224 1225 for (; pmc; pmc = nextpmc) { 1226 nextpmc = pmc->next; 1227 ip_mc_clear_src(pmc); 1228 in_dev_put(pmc->interface); 1229 kfree(pmc); 1230 } 1231 /* clear dead sources, too */ 1232 rcu_read_lock(); 1233 for_each_pmc_rcu(in_dev, pmc) { 1234 struct ip_sf_list *psf, *psf_next; 1235 1236 spin_lock_bh(&pmc->lock); 1237 psf = pmc->tomb; 1238 pmc->tomb = NULL; 1239 spin_unlock_bh(&pmc->lock); 1240 for (; psf; psf = psf_next) { 1241 psf_next = psf->sf_next; 1242 kfree(psf); 1243 } 1244 } 1245 rcu_read_unlock(); 1246 } 1247 #endif 1248 1249 static void igmp_group_dropped(struct ip_mc_list *im) 1250 { 1251 struct in_device *in_dev = im->interface; 1252 #ifdef CONFIG_IP_MULTICAST 1253 struct net *net = dev_net(in_dev->dev); 1254 int reporter; 1255 #endif 1256 1257 if (im->loaded) { 1258 im->loaded = 0; 1259 ip_mc_filter_del(in_dev, im->multiaddr); 1260 } 1261 1262 #ifdef CONFIG_IP_MULTICAST 1263 if (im->multiaddr == IGMP_ALL_HOSTS) 1264 return; 1265 if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports) 1266 return; 1267 1268 reporter = im->reporter; 1269 igmp_stop_timer(im); 1270 1271 if (!in_dev->dead) { 1272 if (IGMP_V1_SEEN(in_dev)) 1273 return; 1274 if (IGMP_V2_SEEN(in_dev)) { 1275 if (reporter) 1276 igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE); 1277 return; 1278 } 1279 /* IGMPv3 */ 1280 igmpv3_add_delrec(in_dev, im); 1281 1282 igmp_ifc_event(in_dev); 1283 } 1284 #endif 1285 } 1286 1287 static void igmp_group_added(struct ip_mc_list *im) 1288 { 1289 struct in_device *in_dev = im->interface; 1290 #ifdef CONFIG_IP_MULTICAST 1291 struct net *net = dev_net(in_dev->dev); 1292 #endif 1293 1294 if (im->loaded == 0) { 1295 im->loaded = 1; 1296 ip_mc_filter_add(in_dev, im->multiaddr); 1297 } 1298 1299 #ifdef CONFIG_IP_MULTICAST 1300 if (im->multiaddr == IGMP_ALL_HOSTS) 1301 return; 1302 if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports) 1303 return; 1304 1305 if (in_dev->dead) 1306 return; 1307 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) { 1308 spin_lock_bh(&im->lock); 1309 igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY); 1310 spin_unlock_bh(&im->lock); 1311 return; 1312 } 1313 /* else, v3 */ 1314 1315 im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1316 igmp_ifc_event(in_dev); 1317 #endif 1318 } 1319 1320 1321 /* 1322 * Multicast list managers 1323 */ 1324 1325 static u32 ip_mc_hash(const struct ip_mc_list *im) 1326 { 1327 return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG); 1328 } 1329 1330 static void ip_mc_hash_add(struct in_device *in_dev, 1331 struct ip_mc_list *im) 1332 { 1333 struct ip_mc_list __rcu **mc_hash; 1334 u32 hash; 1335 1336 mc_hash = rtnl_dereference(in_dev->mc_hash); 1337 if (mc_hash) { 1338 hash = ip_mc_hash(im); 1339 im->next_hash = mc_hash[hash]; 1340 rcu_assign_pointer(mc_hash[hash], im); 1341 return; 1342 } 1343 1344 /* do not use a hash table for small number of items */ 1345 if (in_dev->mc_count < 4) 1346 return; 1347 1348 mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG, 1349 GFP_KERNEL); 1350 if (!mc_hash) 1351 return; 1352 1353 for_each_pmc_rtnl(in_dev, im) { 1354 hash = ip_mc_hash(im); 1355 im->next_hash = mc_hash[hash]; 1356 RCU_INIT_POINTER(mc_hash[hash], im); 1357 } 1358 1359 rcu_assign_pointer(in_dev->mc_hash, mc_hash); 1360 } 1361 1362 static void ip_mc_hash_remove(struct in_device *in_dev, 1363 struct ip_mc_list *im) 1364 { 1365 struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash); 1366 struct ip_mc_list *aux; 1367 1368 if (!mc_hash) 1369 return; 1370 mc_hash += ip_mc_hash(im); 1371 while ((aux = rtnl_dereference(*mc_hash)) != im) 1372 mc_hash = &aux->next_hash; 1373 *mc_hash = im->next_hash; 1374 } 1375 1376 1377 /* 1378 * A socket has joined a multicast group on device dev. 1379 */ 1380 1381 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr) 1382 { 1383 struct ip_mc_list *im; 1384 #ifdef CONFIG_IP_MULTICAST 1385 struct net *net = dev_net(in_dev->dev); 1386 #endif 1387 1388 ASSERT_RTNL(); 1389 1390 for_each_pmc_rtnl(in_dev, im) { 1391 if (im->multiaddr == addr) { 1392 im->users++; 1393 ip_mc_add_src(in_dev, &addr, MCAST_EXCLUDE, 0, NULL, 0); 1394 goto out; 1395 } 1396 } 1397 1398 im = kzalloc(sizeof(*im), GFP_KERNEL); 1399 if (!im) 1400 goto out; 1401 1402 im->users = 1; 1403 im->interface = in_dev; 1404 in_dev_hold(in_dev); 1405 im->multiaddr = addr; 1406 /* initial mode is (EX, empty) */ 1407 im->sfmode = MCAST_EXCLUDE; 1408 im->sfcount[MCAST_EXCLUDE] = 1; 1409 refcount_set(&im->refcnt, 1); 1410 spin_lock_init(&im->lock); 1411 #ifdef CONFIG_IP_MULTICAST 1412 timer_setup(&im->timer, igmp_timer_expire, 0); 1413 im->unsolicit_count = net->ipv4.sysctl_igmp_qrv; 1414 #endif 1415 1416 im->next_rcu = in_dev->mc_list; 1417 in_dev->mc_count++; 1418 rcu_assign_pointer(in_dev->mc_list, im); 1419 1420 ip_mc_hash_add(in_dev, im); 1421 1422 #ifdef CONFIG_IP_MULTICAST 1423 igmpv3_del_delrec(in_dev, im); 1424 #endif 1425 igmp_group_added(im); 1426 if (!in_dev->dead) 1427 ip_rt_multicast_event(in_dev); 1428 out: 1429 return; 1430 } 1431 EXPORT_SYMBOL(ip_mc_inc_group); 1432 1433 static int ip_mc_check_iphdr(struct sk_buff *skb) 1434 { 1435 const struct iphdr *iph; 1436 unsigned int len; 1437 unsigned int offset = skb_network_offset(skb) + sizeof(*iph); 1438 1439 if (!pskb_may_pull(skb, offset)) 1440 return -EINVAL; 1441 1442 iph = ip_hdr(skb); 1443 1444 if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph)) 1445 return -EINVAL; 1446 1447 offset += ip_hdrlen(skb) - sizeof(*iph); 1448 1449 if (!pskb_may_pull(skb, offset)) 1450 return -EINVAL; 1451 1452 iph = ip_hdr(skb); 1453 1454 if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl))) 1455 return -EINVAL; 1456 1457 len = skb_network_offset(skb) + ntohs(iph->tot_len); 1458 if (skb->len < len || len < offset) 1459 return -EINVAL; 1460 1461 skb_set_transport_header(skb, offset); 1462 1463 return 0; 1464 } 1465 1466 static int ip_mc_check_igmp_reportv3(struct sk_buff *skb) 1467 { 1468 unsigned int len = skb_transport_offset(skb); 1469 1470 len += sizeof(struct igmpv3_report); 1471 1472 return pskb_may_pull(skb, len) ? 0 : -EINVAL; 1473 } 1474 1475 static int ip_mc_check_igmp_query(struct sk_buff *skb) 1476 { 1477 unsigned int len = skb_transport_offset(skb); 1478 1479 len += sizeof(struct igmphdr); 1480 if (skb->len < len) 1481 return -EINVAL; 1482 1483 /* IGMPv{1,2}? */ 1484 if (skb->len != len) { 1485 /* or IGMPv3? */ 1486 len += sizeof(struct igmpv3_query) - sizeof(struct igmphdr); 1487 if (skb->len < len || !pskb_may_pull(skb, len)) 1488 return -EINVAL; 1489 } 1490 1491 /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer 1492 * all-systems destination addresses (224.0.0.1) for general queries 1493 */ 1494 if (!igmp_hdr(skb)->group && 1495 ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP)) 1496 return -EINVAL; 1497 1498 return 0; 1499 } 1500 1501 static int ip_mc_check_igmp_msg(struct sk_buff *skb) 1502 { 1503 switch (igmp_hdr(skb)->type) { 1504 case IGMP_HOST_LEAVE_MESSAGE: 1505 case IGMP_HOST_MEMBERSHIP_REPORT: 1506 case IGMPV2_HOST_MEMBERSHIP_REPORT: 1507 /* fall through */ 1508 return 0; 1509 case IGMPV3_HOST_MEMBERSHIP_REPORT: 1510 return ip_mc_check_igmp_reportv3(skb); 1511 case IGMP_HOST_MEMBERSHIP_QUERY: 1512 return ip_mc_check_igmp_query(skb); 1513 default: 1514 return -ENOMSG; 1515 } 1516 } 1517 1518 static inline __sum16 ip_mc_validate_checksum(struct sk_buff *skb) 1519 { 1520 return skb_checksum_simple_validate(skb); 1521 } 1522 1523 static int __ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed) 1524 1525 { 1526 struct sk_buff *skb_chk; 1527 unsigned int transport_len; 1528 unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr); 1529 int ret = -EINVAL; 1530 1531 transport_len = ntohs(ip_hdr(skb)->tot_len) - ip_hdrlen(skb); 1532 1533 skb_chk = skb_checksum_trimmed(skb, transport_len, 1534 ip_mc_validate_checksum); 1535 if (!skb_chk) 1536 goto err; 1537 1538 if (!pskb_may_pull(skb_chk, len)) 1539 goto err; 1540 1541 ret = ip_mc_check_igmp_msg(skb_chk); 1542 if (ret) 1543 goto err; 1544 1545 if (skb_trimmed) 1546 *skb_trimmed = skb_chk; 1547 /* free now unneeded clone */ 1548 else if (skb_chk != skb) 1549 kfree_skb(skb_chk); 1550 1551 ret = 0; 1552 1553 err: 1554 if (ret && skb_chk && skb_chk != skb) 1555 kfree_skb(skb_chk); 1556 1557 return ret; 1558 } 1559 1560 /** 1561 * ip_mc_check_igmp - checks whether this is a sane IGMP packet 1562 * @skb: the skb to validate 1563 * @skb_trimmed: to store an skb pointer trimmed to IPv4 packet tail (optional) 1564 * 1565 * Checks whether an IPv4 packet is a valid IGMP packet. If so sets 1566 * skb transport header accordingly and returns zero. 1567 * 1568 * -EINVAL: A broken packet was detected, i.e. it violates some internet 1569 * standard 1570 * -ENOMSG: IP header validation succeeded but it is not an IGMP packet. 1571 * -ENOMEM: A memory allocation failure happened. 1572 * 1573 * Optionally, an skb pointer might be provided via skb_trimmed (or set it 1574 * to NULL): After parsing an IGMP packet successfully it will point to 1575 * an skb which has its tail aligned to the IP packet end. This might 1576 * either be the originally provided skb or a trimmed, cloned version if 1577 * the skb frame had data beyond the IP packet. A cloned skb allows us 1578 * to leave the original skb and its full frame unchanged (which might be 1579 * desirable for layer 2 frame jugglers). 1580 * 1581 * Caller needs to set the skb network header and free any returned skb if it 1582 * differs from the provided skb. 1583 */ 1584 int ip_mc_check_igmp(struct sk_buff *skb, struct sk_buff **skb_trimmed) 1585 { 1586 int ret = ip_mc_check_iphdr(skb); 1587 1588 if (ret < 0) 1589 return ret; 1590 1591 if (ip_hdr(skb)->protocol != IPPROTO_IGMP) 1592 return -ENOMSG; 1593 1594 return __ip_mc_check_igmp(skb, skb_trimmed); 1595 } 1596 EXPORT_SYMBOL(ip_mc_check_igmp); 1597 1598 /* 1599 * Resend IGMP JOIN report; used by netdev notifier. 1600 */ 1601 static void ip_mc_rejoin_groups(struct in_device *in_dev) 1602 { 1603 #ifdef CONFIG_IP_MULTICAST 1604 struct ip_mc_list *im; 1605 int type; 1606 struct net *net = dev_net(in_dev->dev); 1607 1608 ASSERT_RTNL(); 1609 1610 for_each_pmc_rtnl(in_dev, im) { 1611 if (im->multiaddr == IGMP_ALL_HOSTS) 1612 continue; 1613 if (ipv4_is_local_multicast(im->multiaddr) && 1614 !net->ipv4.sysctl_igmp_llm_reports) 1615 continue; 1616 1617 /* a failover is happening and switches 1618 * must be notified immediately 1619 */ 1620 if (IGMP_V1_SEEN(in_dev)) 1621 type = IGMP_HOST_MEMBERSHIP_REPORT; 1622 else if (IGMP_V2_SEEN(in_dev)) 1623 type = IGMPV2_HOST_MEMBERSHIP_REPORT; 1624 else 1625 type = IGMPV3_HOST_MEMBERSHIP_REPORT; 1626 igmp_send_report(in_dev, im, type); 1627 } 1628 #endif 1629 } 1630 1631 /* 1632 * A socket has left a multicast group on device dev 1633 */ 1634 1635 void ip_mc_dec_group(struct in_device *in_dev, __be32 addr) 1636 { 1637 struct ip_mc_list *i; 1638 struct ip_mc_list __rcu **ip; 1639 1640 ASSERT_RTNL(); 1641 1642 for (ip = &in_dev->mc_list; 1643 (i = rtnl_dereference(*ip)) != NULL; 1644 ip = &i->next_rcu) { 1645 if (i->multiaddr == addr) { 1646 if (--i->users == 0) { 1647 ip_mc_hash_remove(in_dev, i); 1648 *ip = i->next_rcu; 1649 in_dev->mc_count--; 1650 igmp_group_dropped(i); 1651 ip_mc_clear_src(i); 1652 1653 if (!in_dev->dead) 1654 ip_rt_multicast_event(in_dev); 1655 1656 ip_ma_put(i); 1657 return; 1658 } 1659 break; 1660 } 1661 } 1662 } 1663 EXPORT_SYMBOL(ip_mc_dec_group); 1664 1665 /* Device changing type */ 1666 1667 void ip_mc_unmap(struct in_device *in_dev) 1668 { 1669 struct ip_mc_list *pmc; 1670 1671 ASSERT_RTNL(); 1672 1673 for_each_pmc_rtnl(in_dev, pmc) 1674 igmp_group_dropped(pmc); 1675 } 1676 1677 void ip_mc_remap(struct in_device *in_dev) 1678 { 1679 struct ip_mc_list *pmc; 1680 1681 ASSERT_RTNL(); 1682 1683 for_each_pmc_rtnl(in_dev, pmc) { 1684 #ifdef CONFIG_IP_MULTICAST 1685 igmpv3_del_delrec(in_dev, pmc); 1686 #endif 1687 igmp_group_added(pmc); 1688 } 1689 } 1690 1691 /* Device going down */ 1692 1693 void ip_mc_down(struct in_device *in_dev) 1694 { 1695 struct ip_mc_list *pmc; 1696 1697 ASSERT_RTNL(); 1698 1699 for_each_pmc_rtnl(in_dev, pmc) 1700 igmp_group_dropped(pmc); 1701 1702 #ifdef CONFIG_IP_MULTICAST 1703 in_dev->mr_ifc_count = 0; 1704 if (del_timer(&in_dev->mr_ifc_timer)) 1705 __in_dev_put(in_dev); 1706 in_dev->mr_gq_running = 0; 1707 if (del_timer(&in_dev->mr_gq_timer)) 1708 __in_dev_put(in_dev); 1709 #endif 1710 1711 ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS); 1712 } 1713 1714 void ip_mc_init_dev(struct in_device *in_dev) 1715 { 1716 #ifdef CONFIG_IP_MULTICAST 1717 struct net *net = dev_net(in_dev->dev); 1718 #endif 1719 ASSERT_RTNL(); 1720 1721 #ifdef CONFIG_IP_MULTICAST 1722 timer_setup(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 0); 1723 timer_setup(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 0); 1724 in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv; 1725 #endif 1726 1727 spin_lock_init(&in_dev->mc_tomb_lock); 1728 } 1729 1730 /* Device going up */ 1731 1732 void ip_mc_up(struct in_device *in_dev) 1733 { 1734 struct ip_mc_list *pmc; 1735 #ifdef CONFIG_IP_MULTICAST 1736 struct net *net = dev_net(in_dev->dev); 1737 #endif 1738 1739 ASSERT_RTNL(); 1740 1741 #ifdef CONFIG_IP_MULTICAST 1742 in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv; 1743 #endif 1744 ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS); 1745 1746 for_each_pmc_rtnl(in_dev, pmc) { 1747 #ifdef CONFIG_IP_MULTICAST 1748 igmpv3_del_delrec(in_dev, pmc); 1749 #endif 1750 igmp_group_added(pmc); 1751 } 1752 } 1753 1754 /* 1755 * Device is about to be destroyed: clean up. 1756 */ 1757 1758 void ip_mc_destroy_dev(struct in_device *in_dev) 1759 { 1760 struct ip_mc_list *i; 1761 1762 ASSERT_RTNL(); 1763 1764 /* Deactivate timers */ 1765 ip_mc_down(in_dev); 1766 #ifdef CONFIG_IP_MULTICAST 1767 igmpv3_clear_delrec(in_dev); 1768 #endif 1769 1770 while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) { 1771 in_dev->mc_list = i->next_rcu; 1772 in_dev->mc_count--; 1773 ip_ma_put(i); 1774 } 1775 } 1776 1777 /* RTNL is locked */ 1778 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr) 1779 { 1780 struct net_device *dev = NULL; 1781 struct in_device *idev = NULL; 1782 1783 if (imr->imr_ifindex) { 1784 idev = inetdev_by_index(net, imr->imr_ifindex); 1785 return idev; 1786 } 1787 if (imr->imr_address.s_addr) { 1788 dev = __ip_dev_find(net, imr->imr_address.s_addr, false); 1789 if (!dev) 1790 return NULL; 1791 } 1792 1793 if (!dev) { 1794 struct rtable *rt = ip_route_output(net, 1795 imr->imr_multiaddr.s_addr, 1796 0, 0, 0); 1797 if (!IS_ERR(rt)) { 1798 dev = rt->dst.dev; 1799 ip_rt_put(rt); 1800 } 1801 } 1802 if (dev) { 1803 imr->imr_ifindex = dev->ifindex; 1804 idev = __in_dev_get_rtnl(dev); 1805 } 1806 return idev; 1807 } 1808 1809 /* 1810 * Join a socket to a group 1811 */ 1812 1813 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode, 1814 __be32 *psfsrc) 1815 { 1816 struct ip_sf_list *psf, *psf_prev; 1817 int rv = 0; 1818 1819 psf_prev = NULL; 1820 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1821 if (psf->sf_inaddr == *psfsrc) 1822 break; 1823 psf_prev = psf; 1824 } 1825 if (!psf || psf->sf_count[sfmode] == 0) { 1826 /* source filter not found, or count wrong => bug */ 1827 return -ESRCH; 1828 } 1829 psf->sf_count[sfmode]--; 1830 if (psf->sf_count[sfmode] == 0) { 1831 ip_rt_multicast_event(pmc->interface); 1832 } 1833 if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) { 1834 #ifdef CONFIG_IP_MULTICAST 1835 struct in_device *in_dev = pmc->interface; 1836 struct net *net = dev_net(in_dev->dev); 1837 #endif 1838 1839 /* no more filters for this source */ 1840 if (psf_prev) 1841 psf_prev->sf_next = psf->sf_next; 1842 else 1843 pmc->sources = psf->sf_next; 1844 #ifdef CONFIG_IP_MULTICAST 1845 if (psf->sf_oldin && 1846 !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) { 1847 psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1848 psf->sf_next = pmc->tomb; 1849 pmc->tomb = psf; 1850 rv = 1; 1851 } else 1852 #endif 1853 kfree(psf); 1854 } 1855 return rv; 1856 } 1857 1858 #ifndef CONFIG_IP_MULTICAST 1859 #define igmp_ifc_event(x) do { } while (0) 1860 #endif 1861 1862 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 1863 int sfcount, __be32 *psfsrc, int delta) 1864 { 1865 struct ip_mc_list *pmc; 1866 int changerec = 0; 1867 int i, err; 1868 1869 if (!in_dev) 1870 return -ENODEV; 1871 rcu_read_lock(); 1872 for_each_pmc_rcu(in_dev, pmc) { 1873 if (*pmca == pmc->multiaddr) 1874 break; 1875 } 1876 if (!pmc) { 1877 /* MCA not found?? bug */ 1878 rcu_read_unlock(); 1879 return -ESRCH; 1880 } 1881 spin_lock_bh(&pmc->lock); 1882 rcu_read_unlock(); 1883 #ifdef CONFIG_IP_MULTICAST 1884 sf_markstate(pmc); 1885 #endif 1886 if (!delta) { 1887 err = -EINVAL; 1888 if (!pmc->sfcount[sfmode]) 1889 goto out_unlock; 1890 pmc->sfcount[sfmode]--; 1891 } 1892 err = 0; 1893 for (i = 0; i < sfcount; i++) { 1894 int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]); 1895 1896 changerec |= rv > 0; 1897 if (!err && rv < 0) 1898 err = rv; 1899 } 1900 if (pmc->sfmode == MCAST_EXCLUDE && 1901 pmc->sfcount[MCAST_EXCLUDE] == 0 && 1902 pmc->sfcount[MCAST_INCLUDE]) { 1903 #ifdef CONFIG_IP_MULTICAST 1904 struct ip_sf_list *psf; 1905 struct net *net = dev_net(in_dev->dev); 1906 #endif 1907 1908 /* filter mode change */ 1909 pmc->sfmode = MCAST_INCLUDE; 1910 #ifdef CONFIG_IP_MULTICAST 1911 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 1912 in_dev->mr_ifc_count = pmc->crcount; 1913 for (psf = pmc->sources; psf; psf = psf->sf_next) 1914 psf->sf_crcount = 0; 1915 igmp_ifc_event(pmc->interface); 1916 } else if (sf_setstate(pmc) || changerec) { 1917 igmp_ifc_event(pmc->interface); 1918 #endif 1919 } 1920 out_unlock: 1921 spin_unlock_bh(&pmc->lock); 1922 return err; 1923 } 1924 1925 /* 1926 * Add multicast single-source filter to the interface list 1927 */ 1928 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode, 1929 __be32 *psfsrc) 1930 { 1931 struct ip_sf_list *psf, *psf_prev; 1932 1933 psf_prev = NULL; 1934 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1935 if (psf->sf_inaddr == *psfsrc) 1936 break; 1937 psf_prev = psf; 1938 } 1939 if (!psf) { 1940 psf = kzalloc(sizeof(*psf), GFP_ATOMIC); 1941 if (!psf) 1942 return -ENOBUFS; 1943 psf->sf_inaddr = *psfsrc; 1944 if (psf_prev) { 1945 psf_prev->sf_next = psf; 1946 } else 1947 pmc->sources = psf; 1948 } 1949 psf->sf_count[sfmode]++; 1950 if (psf->sf_count[sfmode] == 1) { 1951 ip_rt_multicast_event(pmc->interface); 1952 } 1953 return 0; 1954 } 1955 1956 #ifdef CONFIG_IP_MULTICAST 1957 static void sf_markstate(struct ip_mc_list *pmc) 1958 { 1959 struct ip_sf_list *psf; 1960 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; 1961 1962 for (psf = pmc->sources; psf; psf = psf->sf_next) 1963 if (pmc->sfcount[MCAST_EXCLUDE]) { 1964 psf->sf_oldin = mca_xcount == 1965 psf->sf_count[MCAST_EXCLUDE] && 1966 !psf->sf_count[MCAST_INCLUDE]; 1967 } else 1968 psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0; 1969 } 1970 1971 static int sf_setstate(struct ip_mc_list *pmc) 1972 { 1973 struct ip_sf_list *psf, *dpsf; 1974 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE]; 1975 int qrv = pmc->interface->mr_qrv; 1976 int new_in, rv; 1977 1978 rv = 0; 1979 for (psf = pmc->sources; psf; psf = psf->sf_next) { 1980 if (pmc->sfcount[MCAST_EXCLUDE]) { 1981 new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] && 1982 !psf->sf_count[MCAST_INCLUDE]; 1983 } else 1984 new_in = psf->sf_count[MCAST_INCLUDE] != 0; 1985 if (new_in) { 1986 if (!psf->sf_oldin) { 1987 struct ip_sf_list *prev = NULL; 1988 1989 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) { 1990 if (dpsf->sf_inaddr == psf->sf_inaddr) 1991 break; 1992 prev = dpsf; 1993 } 1994 if (dpsf) { 1995 if (prev) 1996 prev->sf_next = dpsf->sf_next; 1997 else 1998 pmc->tomb = dpsf->sf_next; 1999 kfree(dpsf); 2000 } 2001 psf->sf_crcount = qrv; 2002 rv++; 2003 } 2004 } else if (psf->sf_oldin) { 2005 2006 psf->sf_crcount = 0; 2007 /* 2008 * add or update "delete" records if an active filter 2009 * is now inactive 2010 */ 2011 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) 2012 if (dpsf->sf_inaddr == psf->sf_inaddr) 2013 break; 2014 if (!dpsf) { 2015 dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC); 2016 if (!dpsf) 2017 continue; 2018 *dpsf = *psf; 2019 /* pmc->lock held by callers */ 2020 dpsf->sf_next = pmc->tomb; 2021 pmc->tomb = dpsf; 2022 } 2023 dpsf->sf_crcount = qrv; 2024 rv++; 2025 } 2026 } 2027 return rv; 2028 } 2029 #endif 2030 2031 /* 2032 * Add multicast source filter list to the interface list 2033 */ 2034 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode, 2035 int sfcount, __be32 *psfsrc, int delta) 2036 { 2037 struct ip_mc_list *pmc; 2038 int isexclude; 2039 int i, err; 2040 2041 if (!in_dev) 2042 return -ENODEV; 2043 rcu_read_lock(); 2044 for_each_pmc_rcu(in_dev, pmc) { 2045 if (*pmca == pmc->multiaddr) 2046 break; 2047 } 2048 if (!pmc) { 2049 /* MCA not found?? bug */ 2050 rcu_read_unlock(); 2051 return -ESRCH; 2052 } 2053 spin_lock_bh(&pmc->lock); 2054 rcu_read_unlock(); 2055 2056 #ifdef CONFIG_IP_MULTICAST 2057 sf_markstate(pmc); 2058 #endif 2059 isexclude = pmc->sfmode == MCAST_EXCLUDE; 2060 if (!delta) 2061 pmc->sfcount[sfmode]++; 2062 err = 0; 2063 for (i = 0; i < sfcount; i++) { 2064 err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]); 2065 if (err) 2066 break; 2067 } 2068 if (err) { 2069 int j; 2070 2071 if (!delta) 2072 pmc->sfcount[sfmode]--; 2073 for (j = 0; j < i; j++) 2074 (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]); 2075 } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) { 2076 #ifdef CONFIG_IP_MULTICAST 2077 struct ip_sf_list *psf; 2078 struct net *net = dev_net(pmc->interface->dev); 2079 in_dev = pmc->interface; 2080 #endif 2081 2082 /* filter mode change */ 2083 if (pmc->sfcount[MCAST_EXCLUDE]) 2084 pmc->sfmode = MCAST_EXCLUDE; 2085 else if (pmc->sfcount[MCAST_INCLUDE]) 2086 pmc->sfmode = MCAST_INCLUDE; 2087 #ifdef CONFIG_IP_MULTICAST 2088 /* else no filters; keep old mode for reports */ 2089 2090 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv; 2091 in_dev->mr_ifc_count = pmc->crcount; 2092 for (psf = pmc->sources; psf; psf = psf->sf_next) 2093 psf->sf_crcount = 0; 2094 igmp_ifc_event(in_dev); 2095 } else if (sf_setstate(pmc)) { 2096 igmp_ifc_event(in_dev); 2097 #endif 2098 } 2099 spin_unlock_bh(&pmc->lock); 2100 return err; 2101 } 2102 2103 static void ip_mc_clear_src(struct ip_mc_list *pmc) 2104 { 2105 struct ip_sf_list *psf, *nextpsf, *tomb, *sources; 2106 2107 spin_lock_bh(&pmc->lock); 2108 tomb = pmc->tomb; 2109 pmc->tomb = NULL; 2110 sources = pmc->sources; 2111 pmc->sources = NULL; 2112 pmc->sfmode = MCAST_EXCLUDE; 2113 pmc->sfcount[MCAST_INCLUDE] = 0; 2114 pmc->sfcount[MCAST_EXCLUDE] = 1; 2115 spin_unlock_bh(&pmc->lock); 2116 2117 for (psf = tomb; psf; psf = nextpsf) { 2118 nextpsf = psf->sf_next; 2119 kfree(psf); 2120 } 2121 for (psf = sources; psf; psf = nextpsf) { 2122 nextpsf = psf->sf_next; 2123 kfree(psf); 2124 } 2125 } 2126 2127 /* Join a multicast group 2128 */ 2129 2130 int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr) 2131 { 2132 __be32 addr = imr->imr_multiaddr.s_addr; 2133 struct ip_mc_socklist *iml, *i; 2134 struct in_device *in_dev; 2135 struct inet_sock *inet = inet_sk(sk); 2136 struct net *net = sock_net(sk); 2137 int ifindex; 2138 int count = 0; 2139 int err; 2140 2141 ASSERT_RTNL(); 2142 2143 if (!ipv4_is_multicast(addr)) 2144 return -EINVAL; 2145 2146 in_dev = ip_mc_find_dev(net, imr); 2147 2148 if (!in_dev) { 2149 err = -ENODEV; 2150 goto done; 2151 } 2152 2153 err = -EADDRINUSE; 2154 ifindex = imr->imr_ifindex; 2155 for_each_pmc_rtnl(inet, i) { 2156 if (i->multi.imr_multiaddr.s_addr == addr && 2157 i->multi.imr_ifindex == ifindex) 2158 goto done; 2159 count++; 2160 } 2161 err = -ENOBUFS; 2162 if (count >= net->ipv4.sysctl_igmp_max_memberships) 2163 goto done; 2164 iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL); 2165 if (!iml) 2166 goto done; 2167 2168 memcpy(&iml->multi, imr, sizeof(*imr)); 2169 iml->next_rcu = inet->mc_list; 2170 iml->sflist = NULL; 2171 iml->sfmode = MCAST_EXCLUDE; 2172 rcu_assign_pointer(inet->mc_list, iml); 2173 ip_mc_inc_group(in_dev, addr); 2174 err = 0; 2175 done: 2176 return err; 2177 } 2178 EXPORT_SYMBOL(ip_mc_join_group); 2179 2180 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml, 2181 struct in_device *in_dev) 2182 { 2183 struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist); 2184 int err; 2185 2186 if (!psf) { 2187 /* any-source empty exclude case */ 2188 return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, 2189 iml->sfmode, 0, NULL, 0); 2190 } 2191 err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr, 2192 iml->sfmode, psf->sl_count, psf->sl_addr, 0); 2193 RCU_INIT_POINTER(iml->sflist, NULL); 2194 /* decrease mem now to avoid the memleak warning */ 2195 atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc); 2196 kfree_rcu(psf, rcu); 2197 return err; 2198 } 2199 2200 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr) 2201 { 2202 struct inet_sock *inet = inet_sk(sk); 2203 struct ip_mc_socklist *iml; 2204 struct ip_mc_socklist __rcu **imlp; 2205 struct in_device *in_dev; 2206 struct net *net = sock_net(sk); 2207 __be32 group = imr->imr_multiaddr.s_addr; 2208 u32 ifindex; 2209 int ret = -EADDRNOTAVAIL; 2210 2211 ASSERT_RTNL(); 2212 2213 in_dev = ip_mc_find_dev(net, imr); 2214 if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) { 2215 ret = -ENODEV; 2216 goto out; 2217 } 2218 ifindex = imr->imr_ifindex; 2219 for (imlp = &inet->mc_list; 2220 (iml = rtnl_dereference(*imlp)) != NULL; 2221 imlp = &iml->next_rcu) { 2222 if (iml->multi.imr_multiaddr.s_addr != group) 2223 continue; 2224 if (ifindex) { 2225 if (iml->multi.imr_ifindex != ifindex) 2226 continue; 2227 } else if (imr->imr_address.s_addr && imr->imr_address.s_addr != 2228 iml->multi.imr_address.s_addr) 2229 continue; 2230 2231 (void) ip_mc_leave_src(sk, iml, in_dev); 2232 2233 *imlp = iml->next_rcu; 2234 2235 if (in_dev) 2236 ip_mc_dec_group(in_dev, group); 2237 2238 /* decrease mem now to avoid the memleak warning */ 2239 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); 2240 kfree_rcu(iml, rcu); 2241 return 0; 2242 } 2243 out: 2244 return ret; 2245 } 2246 EXPORT_SYMBOL(ip_mc_leave_group); 2247 2248 int ip_mc_source(int add, int omode, struct sock *sk, struct 2249 ip_mreq_source *mreqs, int ifindex) 2250 { 2251 int err; 2252 struct ip_mreqn imr; 2253 __be32 addr = mreqs->imr_multiaddr; 2254 struct ip_mc_socklist *pmc; 2255 struct in_device *in_dev = NULL; 2256 struct inet_sock *inet = inet_sk(sk); 2257 struct ip_sf_socklist *psl; 2258 struct net *net = sock_net(sk); 2259 int leavegroup = 0; 2260 int i, j, rv; 2261 2262 if (!ipv4_is_multicast(addr)) 2263 return -EINVAL; 2264 2265 ASSERT_RTNL(); 2266 2267 imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr; 2268 imr.imr_address.s_addr = mreqs->imr_interface; 2269 imr.imr_ifindex = ifindex; 2270 in_dev = ip_mc_find_dev(net, &imr); 2271 2272 if (!in_dev) { 2273 err = -ENODEV; 2274 goto done; 2275 } 2276 err = -EADDRNOTAVAIL; 2277 2278 for_each_pmc_rtnl(inet, pmc) { 2279 if ((pmc->multi.imr_multiaddr.s_addr == 2280 imr.imr_multiaddr.s_addr) && 2281 (pmc->multi.imr_ifindex == imr.imr_ifindex)) 2282 break; 2283 } 2284 if (!pmc) { /* must have a prior join */ 2285 err = -EINVAL; 2286 goto done; 2287 } 2288 /* if a source filter was set, must be the same mode as before */ 2289 if (pmc->sflist) { 2290 if (pmc->sfmode != omode) { 2291 err = -EINVAL; 2292 goto done; 2293 } 2294 } else if (pmc->sfmode != omode) { 2295 /* allow mode switches for empty-set filters */ 2296 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0); 2297 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0, 2298 NULL, 0); 2299 pmc->sfmode = omode; 2300 } 2301 2302 psl = rtnl_dereference(pmc->sflist); 2303 if (!add) { 2304 if (!psl) 2305 goto done; /* err = -EADDRNOTAVAIL */ 2306 rv = !0; 2307 for (i = 0; i < psl->sl_count; i++) { 2308 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr, 2309 sizeof(__be32)); 2310 if (rv == 0) 2311 break; 2312 } 2313 if (rv) /* source not found */ 2314 goto done; /* err = -EADDRNOTAVAIL */ 2315 2316 /* special case - (INCLUDE, empty) == LEAVE_GROUP */ 2317 if (psl->sl_count == 1 && omode == MCAST_INCLUDE) { 2318 leavegroup = 1; 2319 goto done; 2320 } 2321 2322 /* update the interface filter */ 2323 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1, 2324 &mreqs->imr_sourceaddr, 1); 2325 2326 for (j = i+1; j < psl->sl_count; j++) 2327 psl->sl_addr[j-1] = psl->sl_addr[j]; 2328 psl->sl_count--; 2329 err = 0; 2330 goto done; 2331 } 2332 /* else, add a new source to the filter */ 2333 2334 if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) { 2335 err = -ENOBUFS; 2336 goto done; 2337 } 2338 if (!psl || psl->sl_count == psl->sl_max) { 2339 struct ip_sf_socklist *newpsl; 2340 int count = IP_SFBLOCK; 2341 2342 if (psl) 2343 count += psl->sl_max; 2344 newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL); 2345 if (!newpsl) { 2346 err = -ENOBUFS; 2347 goto done; 2348 } 2349 newpsl->sl_max = count; 2350 newpsl->sl_count = count - IP_SFBLOCK; 2351 if (psl) { 2352 for (i = 0; i < psl->sl_count; i++) 2353 newpsl->sl_addr[i] = psl->sl_addr[i]; 2354 /* decrease mem now to avoid the memleak warning */ 2355 atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc); 2356 kfree_rcu(psl, rcu); 2357 } 2358 rcu_assign_pointer(pmc->sflist, newpsl); 2359 psl = newpsl; 2360 } 2361 rv = 1; /* > 0 for insert logic below if sl_count is 0 */ 2362 for (i = 0; i < psl->sl_count; i++) { 2363 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr, 2364 sizeof(__be32)); 2365 if (rv == 0) 2366 break; 2367 } 2368 if (rv == 0) /* address already there is an error */ 2369 goto done; 2370 for (j = psl->sl_count-1; j >= i; j--) 2371 psl->sl_addr[j+1] = psl->sl_addr[j]; 2372 psl->sl_addr[i] = mreqs->imr_sourceaddr; 2373 psl->sl_count++; 2374 err = 0; 2375 /* update the interface list */ 2376 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1, 2377 &mreqs->imr_sourceaddr, 1); 2378 done: 2379 if (leavegroup) 2380 err = ip_mc_leave_group(sk, &imr); 2381 return err; 2382 } 2383 2384 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex) 2385 { 2386 int err = 0; 2387 struct ip_mreqn imr; 2388 __be32 addr = msf->imsf_multiaddr; 2389 struct ip_mc_socklist *pmc; 2390 struct in_device *in_dev; 2391 struct inet_sock *inet = inet_sk(sk); 2392 struct ip_sf_socklist *newpsl, *psl; 2393 struct net *net = sock_net(sk); 2394 int leavegroup = 0; 2395 2396 if (!ipv4_is_multicast(addr)) 2397 return -EINVAL; 2398 if (msf->imsf_fmode != MCAST_INCLUDE && 2399 msf->imsf_fmode != MCAST_EXCLUDE) 2400 return -EINVAL; 2401 2402 ASSERT_RTNL(); 2403 2404 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; 2405 imr.imr_address.s_addr = msf->imsf_interface; 2406 imr.imr_ifindex = ifindex; 2407 in_dev = ip_mc_find_dev(net, &imr); 2408 2409 if (!in_dev) { 2410 err = -ENODEV; 2411 goto done; 2412 } 2413 2414 /* special case - (INCLUDE, empty) == LEAVE_GROUP */ 2415 if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) { 2416 leavegroup = 1; 2417 goto done; 2418 } 2419 2420 for_each_pmc_rtnl(inet, pmc) { 2421 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && 2422 pmc->multi.imr_ifindex == imr.imr_ifindex) 2423 break; 2424 } 2425 if (!pmc) { /* must have a prior join */ 2426 err = -EINVAL; 2427 goto done; 2428 } 2429 if (msf->imsf_numsrc) { 2430 newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc), 2431 GFP_KERNEL); 2432 if (!newpsl) { 2433 err = -ENOBUFS; 2434 goto done; 2435 } 2436 newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc; 2437 memcpy(newpsl->sl_addr, msf->imsf_slist, 2438 msf->imsf_numsrc * sizeof(msf->imsf_slist[0])); 2439 err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr, 2440 msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0); 2441 if (err) { 2442 sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max)); 2443 goto done; 2444 } 2445 } else { 2446 newpsl = NULL; 2447 (void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr, 2448 msf->imsf_fmode, 0, NULL, 0); 2449 } 2450 psl = rtnl_dereference(pmc->sflist); 2451 if (psl) { 2452 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, 2453 psl->sl_count, psl->sl_addr, 0); 2454 /* decrease mem now to avoid the memleak warning */ 2455 atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc); 2456 kfree_rcu(psl, rcu); 2457 } else 2458 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode, 2459 0, NULL, 0); 2460 rcu_assign_pointer(pmc->sflist, newpsl); 2461 pmc->sfmode = msf->imsf_fmode; 2462 err = 0; 2463 done: 2464 if (leavegroup) 2465 err = ip_mc_leave_group(sk, &imr); 2466 return err; 2467 } 2468 2469 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf, 2470 struct ip_msfilter __user *optval, int __user *optlen) 2471 { 2472 int err, len, count, copycount; 2473 struct ip_mreqn imr; 2474 __be32 addr = msf->imsf_multiaddr; 2475 struct ip_mc_socklist *pmc; 2476 struct in_device *in_dev; 2477 struct inet_sock *inet = inet_sk(sk); 2478 struct ip_sf_socklist *psl; 2479 struct net *net = sock_net(sk); 2480 2481 ASSERT_RTNL(); 2482 2483 if (!ipv4_is_multicast(addr)) 2484 return -EINVAL; 2485 2486 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr; 2487 imr.imr_address.s_addr = msf->imsf_interface; 2488 imr.imr_ifindex = 0; 2489 in_dev = ip_mc_find_dev(net, &imr); 2490 2491 if (!in_dev) { 2492 err = -ENODEV; 2493 goto done; 2494 } 2495 err = -EADDRNOTAVAIL; 2496 2497 for_each_pmc_rtnl(inet, pmc) { 2498 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr && 2499 pmc->multi.imr_ifindex == imr.imr_ifindex) 2500 break; 2501 } 2502 if (!pmc) /* must have a prior join */ 2503 goto done; 2504 msf->imsf_fmode = pmc->sfmode; 2505 psl = rtnl_dereference(pmc->sflist); 2506 if (!psl) { 2507 len = 0; 2508 count = 0; 2509 } else { 2510 count = psl->sl_count; 2511 } 2512 copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc; 2513 len = copycount * sizeof(psl->sl_addr[0]); 2514 msf->imsf_numsrc = count; 2515 if (put_user(IP_MSFILTER_SIZE(copycount), optlen) || 2516 copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) { 2517 return -EFAULT; 2518 } 2519 if (len && 2520 copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len)) 2521 return -EFAULT; 2522 return 0; 2523 done: 2524 return err; 2525 } 2526 2527 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf, 2528 struct group_filter __user *optval, int __user *optlen) 2529 { 2530 int err, i, count, copycount; 2531 struct sockaddr_in *psin; 2532 __be32 addr; 2533 struct ip_mc_socklist *pmc; 2534 struct inet_sock *inet = inet_sk(sk); 2535 struct ip_sf_socklist *psl; 2536 2537 ASSERT_RTNL(); 2538 2539 psin = (struct sockaddr_in *)&gsf->gf_group; 2540 if (psin->sin_family != AF_INET) 2541 return -EINVAL; 2542 addr = psin->sin_addr.s_addr; 2543 if (!ipv4_is_multicast(addr)) 2544 return -EINVAL; 2545 2546 err = -EADDRNOTAVAIL; 2547 2548 for_each_pmc_rtnl(inet, pmc) { 2549 if (pmc->multi.imr_multiaddr.s_addr == addr && 2550 pmc->multi.imr_ifindex == gsf->gf_interface) 2551 break; 2552 } 2553 if (!pmc) /* must have a prior join */ 2554 goto done; 2555 gsf->gf_fmode = pmc->sfmode; 2556 psl = rtnl_dereference(pmc->sflist); 2557 count = psl ? psl->sl_count : 0; 2558 copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc; 2559 gsf->gf_numsrc = count; 2560 if (put_user(GROUP_FILTER_SIZE(copycount), optlen) || 2561 copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) { 2562 return -EFAULT; 2563 } 2564 for (i = 0; i < copycount; i++) { 2565 struct sockaddr_storage ss; 2566 2567 psin = (struct sockaddr_in *)&ss; 2568 memset(&ss, 0, sizeof(ss)); 2569 psin->sin_family = AF_INET; 2570 psin->sin_addr.s_addr = psl->sl_addr[i]; 2571 if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss))) 2572 return -EFAULT; 2573 } 2574 return 0; 2575 done: 2576 return err; 2577 } 2578 2579 /* 2580 * check if a multicast source filter allows delivery for a given <src,dst,intf> 2581 */ 2582 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, 2583 int dif, int sdif) 2584 { 2585 struct inet_sock *inet = inet_sk(sk); 2586 struct ip_mc_socklist *pmc; 2587 struct ip_sf_socklist *psl; 2588 int i; 2589 int ret; 2590 2591 ret = 1; 2592 if (!ipv4_is_multicast(loc_addr)) 2593 goto out; 2594 2595 rcu_read_lock(); 2596 for_each_pmc_rcu(inet, pmc) { 2597 if (pmc->multi.imr_multiaddr.s_addr == loc_addr && 2598 (pmc->multi.imr_ifindex == dif || 2599 (sdif && pmc->multi.imr_ifindex == sdif))) 2600 break; 2601 } 2602 ret = inet->mc_all; 2603 if (!pmc) 2604 goto unlock; 2605 psl = rcu_dereference(pmc->sflist); 2606 ret = (pmc->sfmode == MCAST_EXCLUDE); 2607 if (!psl) 2608 goto unlock; 2609 2610 for (i = 0; i < psl->sl_count; i++) { 2611 if (psl->sl_addr[i] == rmt_addr) 2612 break; 2613 } 2614 ret = 0; 2615 if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count) 2616 goto unlock; 2617 if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count) 2618 goto unlock; 2619 ret = 1; 2620 unlock: 2621 rcu_read_unlock(); 2622 out: 2623 return ret; 2624 } 2625 2626 /* 2627 * A socket is closing. 2628 */ 2629 2630 void ip_mc_drop_socket(struct sock *sk) 2631 { 2632 struct inet_sock *inet = inet_sk(sk); 2633 struct ip_mc_socklist *iml; 2634 struct net *net = sock_net(sk); 2635 2636 if (!inet->mc_list) 2637 return; 2638 2639 rtnl_lock(); 2640 while ((iml = rtnl_dereference(inet->mc_list)) != NULL) { 2641 struct in_device *in_dev; 2642 2643 inet->mc_list = iml->next_rcu; 2644 in_dev = inetdev_by_index(net, iml->multi.imr_ifindex); 2645 (void) ip_mc_leave_src(sk, iml, in_dev); 2646 if (in_dev) 2647 ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr); 2648 /* decrease mem now to avoid the memleak warning */ 2649 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc); 2650 kfree_rcu(iml, rcu); 2651 } 2652 rtnl_unlock(); 2653 } 2654 2655 /* called with rcu_read_lock() */ 2656 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto) 2657 { 2658 struct ip_mc_list *im; 2659 struct ip_mc_list __rcu **mc_hash; 2660 struct ip_sf_list *psf; 2661 int rv = 0; 2662 2663 mc_hash = rcu_dereference(in_dev->mc_hash); 2664 if (mc_hash) { 2665 u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG); 2666 2667 for (im = rcu_dereference(mc_hash[hash]); 2668 im != NULL; 2669 im = rcu_dereference(im->next_hash)) { 2670 if (im->multiaddr == mc_addr) 2671 break; 2672 } 2673 } else { 2674 for_each_pmc_rcu(in_dev, im) { 2675 if (im->multiaddr == mc_addr) 2676 break; 2677 } 2678 } 2679 if (im && proto == IPPROTO_IGMP) { 2680 rv = 1; 2681 } else if (im) { 2682 if (src_addr) { 2683 for (psf = im->sources; psf; psf = psf->sf_next) { 2684 if (psf->sf_inaddr == src_addr) 2685 break; 2686 } 2687 if (psf) 2688 rv = psf->sf_count[MCAST_INCLUDE] || 2689 psf->sf_count[MCAST_EXCLUDE] != 2690 im->sfcount[MCAST_EXCLUDE]; 2691 else 2692 rv = im->sfcount[MCAST_EXCLUDE] != 0; 2693 } else 2694 rv = 1; /* unspecified source; tentatively allow */ 2695 } 2696 return rv; 2697 } 2698 2699 #if defined(CONFIG_PROC_FS) 2700 struct igmp_mc_iter_state { 2701 struct seq_net_private p; 2702 struct net_device *dev; 2703 struct in_device *in_dev; 2704 }; 2705 2706 #define igmp_mc_seq_private(seq) ((struct igmp_mc_iter_state *)(seq)->private) 2707 2708 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq) 2709 { 2710 struct net *net = seq_file_net(seq); 2711 struct ip_mc_list *im = NULL; 2712 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2713 2714 state->in_dev = NULL; 2715 for_each_netdev_rcu(net, state->dev) { 2716 struct in_device *in_dev; 2717 2718 in_dev = __in_dev_get_rcu(state->dev); 2719 if (!in_dev) 2720 continue; 2721 im = rcu_dereference(in_dev->mc_list); 2722 if (im) { 2723 state->in_dev = in_dev; 2724 break; 2725 } 2726 } 2727 return im; 2728 } 2729 2730 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im) 2731 { 2732 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2733 2734 im = rcu_dereference(im->next_rcu); 2735 while (!im) { 2736 state->dev = next_net_device_rcu(state->dev); 2737 if (!state->dev) { 2738 state->in_dev = NULL; 2739 break; 2740 } 2741 state->in_dev = __in_dev_get_rcu(state->dev); 2742 if (!state->in_dev) 2743 continue; 2744 im = rcu_dereference(state->in_dev->mc_list); 2745 } 2746 return im; 2747 } 2748 2749 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos) 2750 { 2751 struct ip_mc_list *im = igmp_mc_get_first(seq); 2752 if (im) 2753 while (pos && (im = igmp_mc_get_next(seq, im)) != NULL) 2754 --pos; 2755 return pos ? NULL : im; 2756 } 2757 2758 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos) 2759 __acquires(rcu) 2760 { 2761 rcu_read_lock(); 2762 return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 2763 } 2764 2765 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2766 { 2767 struct ip_mc_list *im; 2768 if (v == SEQ_START_TOKEN) 2769 im = igmp_mc_get_first(seq); 2770 else 2771 im = igmp_mc_get_next(seq, v); 2772 ++*pos; 2773 return im; 2774 } 2775 2776 static void igmp_mc_seq_stop(struct seq_file *seq, void *v) 2777 __releases(rcu) 2778 { 2779 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2780 2781 state->in_dev = NULL; 2782 state->dev = NULL; 2783 rcu_read_unlock(); 2784 } 2785 2786 static int igmp_mc_seq_show(struct seq_file *seq, void *v) 2787 { 2788 if (v == SEQ_START_TOKEN) 2789 seq_puts(seq, 2790 "Idx\tDevice : Count Querier\tGroup Users Timer\tReporter\n"); 2791 else { 2792 struct ip_mc_list *im = (struct ip_mc_list *)v; 2793 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); 2794 char *querier; 2795 long delta; 2796 2797 #ifdef CONFIG_IP_MULTICAST 2798 querier = IGMP_V1_SEEN(state->in_dev) ? "V1" : 2799 IGMP_V2_SEEN(state->in_dev) ? "V2" : 2800 "V3"; 2801 #else 2802 querier = "NONE"; 2803 #endif 2804 2805 if (rcu_access_pointer(state->in_dev->mc_list) == im) { 2806 seq_printf(seq, "%d\t%-10s: %5d %7s\n", 2807 state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier); 2808 } 2809 2810 delta = im->timer.expires - jiffies; 2811 seq_printf(seq, 2812 "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n", 2813 im->multiaddr, im->users, 2814 im->tm_running, 2815 im->tm_running ? jiffies_delta_to_clock_t(delta) : 0, 2816 im->reporter); 2817 } 2818 return 0; 2819 } 2820 2821 static const struct seq_operations igmp_mc_seq_ops = { 2822 .start = igmp_mc_seq_start, 2823 .next = igmp_mc_seq_next, 2824 .stop = igmp_mc_seq_stop, 2825 .show = igmp_mc_seq_show, 2826 }; 2827 2828 static int igmp_mc_seq_open(struct inode *inode, struct file *file) 2829 { 2830 return seq_open_net(inode, file, &igmp_mc_seq_ops, 2831 sizeof(struct igmp_mc_iter_state)); 2832 } 2833 2834 static const struct file_operations igmp_mc_seq_fops = { 2835 .owner = THIS_MODULE, 2836 .open = igmp_mc_seq_open, 2837 .read = seq_read, 2838 .llseek = seq_lseek, 2839 .release = seq_release_net, 2840 }; 2841 2842 struct igmp_mcf_iter_state { 2843 struct seq_net_private p; 2844 struct net_device *dev; 2845 struct in_device *idev; 2846 struct ip_mc_list *im; 2847 }; 2848 2849 #define igmp_mcf_seq_private(seq) ((struct igmp_mcf_iter_state *)(seq)->private) 2850 2851 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq) 2852 { 2853 struct net *net = seq_file_net(seq); 2854 struct ip_sf_list *psf = NULL; 2855 struct ip_mc_list *im = NULL; 2856 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2857 2858 state->idev = NULL; 2859 state->im = NULL; 2860 for_each_netdev_rcu(net, state->dev) { 2861 struct in_device *idev; 2862 idev = __in_dev_get_rcu(state->dev); 2863 if (unlikely(!idev)) 2864 continue; 2865 im = rcu_dereference(idev->mc_list); 2866 if (likely(im)) { 2867 spin_lock_bh(&im->lock); 2868 psf = im->sources; 2869 if (likely(psf)) { 2870 state->im = im; 2871 state->idev = idev; 2872 break; 2873 } 2874 spin_unlock_bh(&im->lock); 2875 } 2876 } 2877 return psf; 2878 } 2879 2880 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf) 2881 { 2882 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2883 2884 psf = psf->sf_next; 2885 while (!psf) { 2886 spin_unlock_bh(&state->im->lock); 2887 state->im = state->im->next; 2888 while (!state->im) { 2889 state->dev = next_net_device_rcu(state->dev); 2890 if (!state->dev) { 2891 state->idev = NULL; 2892 goto out; 2893 } 2894 state->idev = __in_dev_get_rcu(state->dev); 2895 if (!state->idev) 2896 continue; 2897 state->im = rcu_dereference(state->idev->mc_list); 2898 } 2899 if (!state->im) 2900 break; 2901 spin_lock_bh(&state->im->lock); 2902 psf = state->im->sources; 2903 } 2904 out: 2905 return psf; 2906 } 2907 2908 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos) 2909 { 2910 struct ip_sf_list *psf = igmp_mcf_get_first(seq); 2911 if (psf) 2912 while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL) 2913 --pos; 2914 return pos ? NULL : psf; 2915 } 2916 2917 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos) 2918 __acquires(rcu) 2919 { 2920 rcu_read_lock(); 2921 return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 2922 } 2923 2924 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2925 { 2926 struct ip_sf_list *psf; 2927 if (v == SEQ_START_TOKEN) 2928 psf = igmp_mcf_get_first(seq); 2929 else 2930 psf = igmp_mcf_get_next(seq, v); 2931 ++*pos; 2932 return psf; 2933 } 2934 2935 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v) 2936 __releases(rcu) 2937 { 2938 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2939 if (likely(state->im)) { 2940 spin_unlock_bh(&state->im->lock); 2941 state->im = NULL; 2942 } 2943 state->idev = NULL; 2944 state->dev = NULL; 2945 rcu_read_unlock(); 2946 } 2947 2948 static int igmp_mcf_seq_show(struct seq_file *seq, void *v) 2949 { 2950 struct ip_sf_list *psf = (struct ip_sf_list *)v; 2951 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq); 2952 2953 if (v == SEQ_START_TOKEN) { 2954 seq_puts(seq, "Idx Device MCA SRC INC EXC\n"); 2955 } else { 2956 seq_printf(seq, 2957 "%3d %6.6s 0x%08x " 2958 "0x%08x %6lu %6lu\n", 2959 state->dev->ifindex, state->dev->name, 2960 ntohl(state->im->multiaddr), 2961 ntohl(psf->sf_inaddr), 2962 psf->sf_count[MCAST_INCLUDE], 2963 psf->sf_count[MCAST_EXCLUDE]); 2964 } 2965 return 0; 2966 } 2967 2968 static const struct seq_operations igmp_mcf_seq_ops = { 2969 .start = igmp_mcf_seq_start, 2970 .next = igmp_mcf_seq_next, 2971 .stop = igmp_mcf_seq_stop, 2972 .show = igmp_mcf_seq_show, 2973 }; 2974 2975 static int igmp_mcf_seq_open(struct inode *inode, struct file *file) 2976 { 2977 return seq_open_net(inode, file, &igmp_mcf_seq_ops, 2978 sizeof(struct igmp_mcf_iter_state)); 2979 } 2980 2981 static const struct file_operations igmp_mcf_seq_fops = { 2982 .owner = THIS_MODULE, 2983 .open = igmp_mcf_seq_open, 2984 .read = seq_read, 2985 .llseek = seq_lseek, 2986 .release = seq_release_net, 2987 }; 2988 2989 static int __net_init igmp_net_init(struct net *net) 2990 { 2991 struct proc_dir_entry *pde; 2992 int err; 2993 2994 pde = proc_create("igmp", S_IRUGO, net->proc_net, &igmp_mc_seq_fops); 2995 if (!pde) 2996 goto out_igmp; 2997 pde = proc_create("mcfilter", S_IRUGO, net->proc_net, 2998 &igmp_mcf_seq_fops); 2999 if (!pde) 3000 goto out_mcfilter; 3001 err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET, 3002 SOCK_DGRAM, 0, net); 3003 if (err < 0) { 3004 pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n", 3005 err); 3006 goto out_sock; 3007 } 3008 3009 return 0; 3010 3011 out_sock: 3012 remove_proc_entry("mcfilter", net->proc_net); 3013 out_mcfilter: 3014 remove_proc_entry("igmp", net->proc_net); 3015 out_igmp: 3016 return -ENOMEM; 3017 } 3018 3019 static void __net_exit igmp_net_exit(struct net *net) 3020 { 3021 remove_proc_entry("mcfilter", net->proc_net); 3022 remove_proc_entry("igmp", net->proc_net); 3023 inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk); 3024 } 3025 3026 static struct pernet_operations igmp_net_ops = { 3027 .init = igmp_net_init, 3028 .exit = igmp_net_exit, 3029 }; 3030 #endif 3031 3032 static int igmp_netdev_event(struct notifier_block *this, 3033 unsigned long event, void *ptr) 3034 { 3035 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 3036 struct in_device *in_dev; 3037 3038 switch (event) { 3039 case NETDEV_RESEND_IGMP: 3040 in_dev = __in_dev_get_rtnl(dev); 3041 if (in_dev) 3042 ip_mc_rejoin_groups(in_dev); 3043 break; 3044 default: 3045 break; 3046 } 3047 return NOTIFY_DONE; 3048 } 3049 3050 static struct notifier_block igmp_notifier = { 3051 .notifier_call = igmp_netdev_event, 3052 }; 3053 3054 int __init igmp_mc_init(void) 3055 { 3056 #if defined(CONFIG_PROC_FS) 3057 int err; 3058 3059 err = register_pernet_subsys(&igmp_net_ops); 3060 if (err) 3061 return err; 3062 err = register_netdevice_notifier(&igmp_notifier); 3063 if (err) 3064 goto reg_notif_fail; 3065 return 0; 3066 3067 reg_notif_fail: 3068 unregister_pernet_subsys(&igmp_net_ops); 3069 return err; 3070 #else 3071 return register_netdevice_notifier(&igmp_notifier); 3072 #endif 3073 } 3074