1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2009 Bruce Simpson. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote 15 * products derived from this software without specific prior written 16 * permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * 30 * $KAME: mld6.c,v 1.27 2001/04/04 05:17:30 itojun Exp $ 31 */ 32 33 /*- 34 * Copyright (c) 1988 Stephen Deering. 35 * Copyright (c) 1992, 1993 36 * The Regents of the University of California. All rights reserved. 37 * 38 * This code is derived from software contributed to Berkeley by 39 * Stephen Deering of Stanford University. 40 * 41 * Redistribution and use in source and binary forms, with or without 42 * modification, are permitted provided that the following conditions 43 * are met: 44 * 1. Redistributions of source code must retain the above copyright 45 * notice, this list of conditions and the following disclaimer. 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in the 48 * documentation and/or other materials provided with the distribution. 49 * 3. Neither the name of the University nor the names of its contributors 50 * may be used to endorse or promote products derived from this software 51 * without specific prior written permission. 52 * 53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 63 * SUCH DAMAGE. 64 * 65 * @(#)igmp.c 8.1 (Berkeley) 7/19/93 66 */ 67 68 #include <sys/cdefs.h> 69 __FBSDID("$FreeBSD$"); 70 71 #include "opt_inet.h" 72 #include "opt_inet6.h" 73 74 #include <sys/param.h> 75 #include <sys/systm.h> 76 #include <sys/mbuf.h> 77 #include <sys/socket.h> 78 #include <sys/sysctl.h> 79 #include <sys/kernel.h> 80 #include <sys/callout.h> 81 #include <sys/malloc.h> 82 #include <sys/module.h> 83 #include <sys/ktr.h> 84 85 #include <net/if.h> 86 #include <net/if_var.h> 87 #include <net/route.h> 88 #include <net/vnet.h> 89 90 #include <netinet/in.h> 91 #include <netinet/in_var.h> 92 #include <netinet6/in6_var.h> 93 #include <netinet/ip6.h> 94 #include <netinet6/ip6_var.h> 95 #include <netinet6/scope6_var.h> 96 #include <netinet/icmp6.h> 97 #include <netinet6/mld6.h> 98 #include <netinet6/mld6_var.h> 99 100 #include <security/mac/mac_framework.h> 101 102 #ifndef KTR_MLD 103 #define KTR_MLD KTR_INET6 104 #endif 105 106 static void mli_delete_locked(const struct ifnet *); 107 static void mld_dispatch_packet(struct mbuf *); 108 static void mld_dispatch_queue(struct mbufq *, int); 109 static void mld_final_leave(struct in6_multi *, struct mld_ifsoftc *); 110 static void mld_fasttimo_vnet(struct in6_multi_head *inmh); 111 static int mld_handle_state_change(struct in6_multi *, 112 struct mld_ifsoftc *); 113 static int mld_initial_join(struct in6_multi *, struct mld_ifsoftc *, 114 const int); 115 #ifdef KTR 116 static char * mld_rec_type_to_str(const int); 117 #endif 118 static void mld_set_version(struct mld_ifsoftc *, const int); 119 static void mld_slowtimo_vnet(void); 120 static int mld_v1_input_query(struct ifnet *, const struct ip6_hdr *, 121 /*const*/ struct mld_hdr *); 122 static int mld_v1_input_report(struct ifnet *, const struct ip6_hdr *, 123 /*const*/ struct mld_hdr *); 124 static void mld_v1_process_group_timer(struct in6_multi_head *, 125 struct in6_multi *); 126 static void mld_v1_process_querier_timers(struct mld_ifsoftc *); 127 static int mld_v1_transmit_report(struct in6_multi *, const int); 128 static void mld_v1_update_group(struct in6_multi *, const int); 129 static void mld_v2_cancel_link_timers(struct mld_ifsoftc *); 130 static void mld_v2_dispatch_general_query(struct mld_ifsoftc *); 131 static struct mbuf * 132 mld_v2_encap_report(struct ifnet *, struct mbuf *); 133 static int mld_v2_enqueue_filter_change(struct mbufq *, 134 struct in6_multi *); 135 static int mld_v2_enqueue_group_record(struct mbufq *, 136 struct in6_multi *, const int, const int, const int, 137 const int); 138 static int mld_v2_input_query(struct ifnet *, const struct ip6_hdr *, 139 struct mbuf *, struct mldv2_query *, const int, const int); 140 static int mld_v2_merge_state_changes(struct in6_multi *, 141 struct mbufq *); 142 static void mld_v2_process_group_timers(struct in6_multi_head *, 143 struct mbufq *, struct mbufq *, 144 struct in6_multi *, const int); 145 static int mld_v2_process_group_query(struct in6_multi *, 146 struct mld_ifsoftc *mli, int, struct mbuf *, 147 struct mldv2_query *, const int); 148 static int sysctl_mld_gsr(SYSCTL_HANDLER_ARGS); 149 static int sysctl_mld_ifinfo(SYSCTL_HANDLER_ARGS); 150 151 /* 152 * Normative references: RFC 2710, RFC 3590, RFC 3810. 153 * 154 * Locking: 155 * * The MLD subsystem lock ends up being system-wide for the moment, 156 * but could be per-VIMAGE later on. 157 * * The permitted lock order is: IN6_MULTI_LOCK, MLD_LOCK, IF_ADDR_LOCK. 158 * Any may be taken independently; if any are held at the same 159 * time, the above lock order must be followed. 160 * * IN6_MULTI_LOCK covers in_multi. 161 * * MLD_LOCK covers per-link state and any global variables in this file. 162 * * IF_ADDR_LOCK covers if_multiaddrs, which is used for a variety of 163 * per-link state iterators. 164 * 165 * XXX LOR PREVENTION 166 * A special case for IPv6 is the in6_setscope() routine. ip6_output() 167 * will not accept an ifp; it wants an embedded scope ID, unlike 168 * ip_output(), which happily takes the ifp given to it. The embedded 169 * scope ID is only used by MLD to select the outgoing interface. 170 * 171 * During interface attach and detach, MLD will take MLD_LOCK *after* 172 * the IF_AFDATA_LOCK. 173 * As in6_setscope() takes IF_AFDATA_LOCK then SCOPE_LOCK, we can't call 174 * it with MLD_LOCK held without triggering an LOR. A netisr with indirect 175 * dispatch could work around this, but we'd rather not do that, as it 176 * can introduce other races. 177 * 178 * As such, we exploit the fact that the scope ID is just the interface 179 * index, and embed it in the IPv6 destination address accordingly. 180 * This is potentially NOT VALID for MLDv1 reports, as they 181 * are always sent to the multicast group itself; as MLDv2 182 * reports are always sent to ff02::16, this is not an issue 183 * when MLDv2 is in use. 184 * 185 * This does not however eliminate the LOR when ip6_output() itself 186 * calls in6_setscope() internally whilst MLD_LOCK is held. This will 187 * trigger a LOR warning in WITNESS when the ifnet is detached. 188 * 189 * The right answer is probably to make IF_AFDATA_LOCK an rwlock, given 190 * how it's used across the network stack. Here we're simply exploiting 191 * the fact that MLD runs at a similar layer in the stack to scope6.c. 192 * 193 * VIMAGE: 194 * * Each in6_multi corresponds to an ifp, and each ifp corresponds 195 * to a vnet in ifp->if_vnet. 196 */ 197 static struct mtx mld_mtx; 198 static MALLOC_DEFINE(M_MLD, "mld", "mld state"); 199 200 #define MLD_EMBEDSCOPE(pin6, zoneid) \ 201 if (IN6_IS_SCOPE_LINKLOCAL(pin6) || \ 202 IN6_IS_ADDR_MC_INTFACELOCAL(pin6)) \ 203 (pin6)->s6_addr16[1] = htons((zoneid) & 0xFFFF) \ 204 205 /* 206 * VIMAGE-wide globals. 207 */ 208 VNET_DEFINE_STATIC(struct timeval, mld_gsrdelay) = {10, 0}; 209 VNET_DEFINE_STATIC(LIST_HEAD(, mld_ifsoftc), mli_head); 210 VNET_DEFINE_STATIC(int, interface_timers_running6); 211 VNET_DEFINE_STATIC(int, state_change_timers_running6); 212 VNET_DEFINE_STATIC(int, current_state_timers_running6); 213 214 #define V_mld_gsrdelay VNET(mld_gsrdelay) 215 #define V_mli_head VNET(mli_head) 216 #define V_interface_timers_running6 VNET(interface_timers_running6) 217 #define V_state_change_timers_running6 VNET(state_change_timers_running6) 218 #define V_current_state_timers_running6 VNET(current_state_timers_running6) 219 220 SYSCTL_DECL(_net_inet6); /* Note: Not in any common header. */ 221 222 SYSCTL_NODE(_net_inet6, OID_AUTO, mld, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 223 "IPv6 Multicast Listener Discovery"); 224 225 /* 226 * Virtualized sysctls. 227 */ 228 SYSCTL_PROC(_net_inet6_mld, OID_AUTO, gsrdelay, 229 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 230 &VNET_NAME(mld_gsrdelay.tv_sec), 0, sysctl_mld_gsr, "I", 231 "Rate limit for MLDv2 Group-and-Source queries in seconds"); 232 233 /* 234 * Non-virtualized sysctls. 235 */ 236 static SYSCTL_NODE(_net_inet6_mld, OID_AUTO, ifinfo, 237 CTLFLAG_RD | CTLFLAG_MPSAFE, sysctl_mld_ifinfo, 238 "Per-interface MLDv2 state"); 239 240 static int mld_v1enable = 1; 241 SYSCTL_INT(_net_inet6_mld, OID_AUTO, v1enable, CTLFLAG_RWTUN, 242 &mld_v1enable, 0, "Enable fallback to MLDv1"); 243 244 static int mld_v2enable = 1; 245 SYSCTL_INT(_net_inet6_mld, OID_AUTO, v2enable, CTLFLAG_RWTUN, 246 &mld_v2enable, 0, "Enable MLDv2"); 247 248 static int mld_use_allow = 1; 249 SYSCTL_INT(_net_inet6_mld, OID_AUTO, use_allow, CTLFLAG_RWTUN, 250 &mld_use_allow, 0, "Use ALLOW/BLOCK for RFC 4604 SSM joins/leaves"); 251 252 /* 253 * Packed Router Alert option structure declaration. 254 */ 255 struct mld_raopt { 256 struct ip6_hbh hbh; 257 struct ip6_opt pad; 258 struct ip6_opt_router ra; 259 } __packed; 260 261 /* 262 * Router Alert hop-by-hop option header. 263 */ 264 static struct mld_raopt mld_ra = { 265 .hbh = { 0, 0 }, 266 .pad = { .ip6o_type = IP6OPT_PADN, 0 }, 267 .ra = { 268 .ip6or_type = IP6OPT_ROUTER_ALERT, 269 .ip6or_len = IP6OPT_RTALERT_LEN - 2, 270 .ip6or_value[0] = ((IP6OPT_RTALERT_MLD >> 8) & 0xFF), 271 .ip6or_value[1] = (IP6OPT_RTALERT_MLD & 0xFF) 272 } 273 }; 274 static struct ip6_pktopts mld_po; 275 276 static __inline void 277 mld_save_context(struct mbuf *m, struct ifnet *ifp) 278 { 279 280 #ifdef VIMAGE 281 m->m_pkthdr.PH_loc.ptr = ifp->if_vnet; 282 #endif /* VIMAGE */ 283 m->m_pkthdr.rcvif = ifp; 284 m->m_pkthdr.flowid = ifp->if_index; 285 } 286 287 static __inline void 288 mld_scrub_context(struct mbuf *m) 289 { 290 291 m->m_pkthdr.PH_loc.ptr = NULL; 292 m->m_pkthdr.flowid = 0; 293 } 294 295 /* 296 * Restore context from a queued output chain. 297 * Return saved ifindex. 298 * 299 * VIMAGE: The assertion is there to make sure that we 300 * actually called CURVNET_SET() with what's in the mbuf chain. 301 */ 302 static __inline uint32_t 303 mld_restore_context(struct mbuf *m) 304 { 305 306 #if defined(VIMAGE) && defined(INVARIANTS) 307 KASSERT(curvnet == m->m_pkthdr.PH_loc.ptr, 308 ("%s: called when curvnet was not restored: cuvnet %p m ptr %p", 309 __func__, curvnet, m->m_pkthdr.PH_loc.ptr)); 310 #endif 311 return (m->m_pkthdr.flowid); 312 } 313 314 /* 315 * Retrieve or set threshold between group-source queries in seconds. 316 * 317 * VIMAGE: Assume curvnet set by caller. 318 * SMPng: NOTE: Serialized by MLD lock. 319 */ 320 static int 321 sysctl_mld_gsr(SYSCTL_HANDLER_ARGS) 322 { 323 int error; 324 int i; 325 326 error = sysctl_wire_old_buffer(req, sizeof(int)); 327 if (error) 328 return (error); 329 330 MLD_LOCK(); 331 332 i = V_mld_gsrdelay.tv_sec; 333 334 error = sysctl_handle_int(oidp, &i, 0, req); 335 if (error || !req->newptr) 336 goto out_locked; 337 338 if (i < -1 || i >= 60) { 339 error = EINVAL; 340 goto out_locked; 341 } 342 343 CTR2(KTR_MLD, "change mld_gsrdelay from %d to %d", 344 V_mld_gsrdelay.tv_sec, i); 345 V_mld_gsrdelay.tv_sec = i; 346 347 out_locked: 348 MLD_UNLOCK(); 349 return (error); 350 } 351 352 /* 353 * Expose struct mld_ifsoftc to userland, keyed by ifindex. 354 * For use by ifmcstat(8). 355 * 356 * VIMAGE: Assume curvnet set by caller. The node handler itself 357 * is not directly virtualized. 358 */ 359 static int 360 sysctl_mld_ifinfo(SYSCTL_HANDLER_ARGS) 361 { 362 struct epoch_tracker et; 363 int *name; 364 int error; 365 u_int namelen; 366 struct ifnet *ifp; 367 struct mld_ifsoftc *mli; 368 369 name = (int *)arg1; 370 namelen = arg2; 371 372 if (req->newptr != NULL) 373 return (EPERM); 374 375 if (namelen != 1) 376 return (EINVAL); 377 378 error = sysctl_wire_old_buffer(req, sizeof(struct mld_ifinfo)); 379 if (error) 380 return (error); 381 382 IN6_MULTI_LOCK(); 383 IN6_MULTI_LIST_LOCK(); 384 MLD_LOCK(); 385 NET_EPOCH_ENTER(et); 386 387 error = ENOENT; 388 ifp = ifnet_byindex(name[0]); 389 if (ifp == NULL) 390 goto out_locked; 391 392 LIST_FOREACH(mli, &V_mli_head, mli_link) { 393 if (ifp == mli->mli_ifp) { 394 struct mld_ifinfo info; 395 396 info.mli_version = mli->mli_version; 397 info.mli_v1_timer = mli->mli_v1_timer; 398 info.mli_v2_timer = mli->mli_v2_timer; 399 info.mli_flags = mli->mli_flags; 400 info.mli_rv = mli->mli_rv; 401 info.mli_qi = mli->mli_qi; 402 info.mli_qri = mli->mli_qri; 403 info.mli_uri = mli->mli_uri; 404 error = SYSCTL_OUT(req, &info, sizeof(info)); 405 break; 406 } 407 } 408 409 out_locked: 410 NET_EPOCH_EXIT(et); 411 MLD_UNLOCK(); 412 IN6_MULTI_LIST_UNLOCK(); 413 IN6_MULTI_UNLOCK(); 414 return (error); 415 } 416 417 /* 418 * Dispatch an entire queue of pending packet chains. 419 * VIMAGE: Assumes the vnet pointer has been set. 420 */ 421 static void 422 mld_dispatch_queue(struct mbufq *mq, int limit) 423 { 424 struct mbuf *m; 425 426 while ((m = mbufq_dequeue(mq)) != NULL) { 427 CTR3(KTR_MLD, "%s: dispatch %p from %p", __func__, mq, m); 428 mld_dispatch_packet(m); 429 if (--limit == 0) 430 break; 431 } 432 } 433 434 /* 435 * Filter outgoing MLD report state by group. 436 * 437 * Reports are ALWAYS suppressed for ALL-HOSTS (ff02::1) 438 * and node-local addresses. However, kernel and socket consumers 439 * always embed the KAME scope ID in the address provided, so strip it 440 * when performing comparison. 441 * Note: This is not the same as the *multicast* scope. 442 * 443 * Return zero if the given group is one for which MLD reports 444 * should be suppressed, or non-zero if reports should be issued. 445 */ 446 static __inline int 447 mld_is_addr_reported(const struct in6_addr *addr) 448 { 449 450 KASSERT(IN6_IS_ADDR_MULTICAST(addr), ("%s: not multicast", __func__)); 451 452 if (IPV6_ADDR_MC_SCOPE(addr) == IPV6_ADDR_SCOPE_NODELOCAL) 453 return (0); 454 455 if (IPV6_ADDR_MC_SCOPE(addr) == IPV6_ADDR_SCOPE_LINKLOCAL) { 456 struct in6_addr tmp = *addr; 457 in6_clearscope(&tmp); 458 if (IN6_ARE_ADDR_EQUAL(&tmp, &in6addr_linklocal_allnodes)) 459 return (0); 460 } 461 462 return (1); 463 } 464 465 /* 466 * Attach MLD when PF_INET6 is attached to an interface. Assumes that the 467 * current VNET is set by the caller. 468 */ 469 struct mld_ifsoftc * 470 mld_domifattach(struct ifnet *ifp) 471 { 472 struct mld_ifsoftc *mli; 473 474 CTR3(KTR_MLD, "%s: called for ifp %p(%s)", __func__, ifp, if_name(ifp)); 475 476 mli = malloc(sizeof(struct mld_ifsoftc), M_MLD, M_WAITOK | M_ZERO); 477 mli->mli_ifp = ifp; 478 mli->mli_version = MLD_VERSION_2; 479 mli->mli_flags = 0; 480 mli->mli_rv = MLD_RV_INIT; 481 mli->mli_qi = MLD_QI_INIT; 482 mli->mli_qri = MLD_QRI_INIT; 483 mli->mli_uri = MLD_URI_INIT; 484 mbufq_init(&mli->mli_gq, MLD_MAX_RESPONSE_PACKETS); 485 if ((ifp->if_flags & IFF_MULTICAST) == 0) 486 mli->mli_flags |= MLIF_SILENT; 487 if (mld_use_allow) 488 mli->mli_flags |= MLIF_USEALLOW; 489 490 MLD_LOCK(); 491 LIST_INSERT_HEAD(&V_mli_head, mli, mli_link); 492 MLD_UNLOCK(); 493 494 return (mli); 495 } 496 497 /* 498 * Hook for ifdetach. 499 * 500 * NOTE: Some finalization tasks need to run before the protocol domain 501 * is detached, but also before the link layer does its cleanup. 502 * Run before link-layer cleanup; cleanup groups, but do not free MLD state. 503 * 504 * SMPng: Caller must hold IN6_MULTI_LOCK(). 505 * Must take IF_ADDR_LOCK() to cover if_multiaddrs iterator. 506 * XXX This routine is also bitten by unlocked ifma_protospec access. 507 */ 508 void 509 mld_ifdetach(struct ifnet *ifp, struct in6_multi_head *inmh) 510 { 511 struct epoch_tracker et; 512 struct mld_ifsoftc *mli; 513 struct ifmultiaddr *ifma; 514 struct in6_multi *inm; 515 516 CTR3(KTR_MLD, "%s: called for ifp %p(%s)", __func__, ifp, 517 if_name(ifp)); 518 519 IN6_MULTI_LIST_LOCK_ASSERT(); 520 MLD_LOCK(); 521 522 mli = MLD_IFINFO(ifp); 523 IF_ADDR_WLOCK(ifp); 524 /* 525 * Extract list of in6_multi associated with the detaching ifp 526 * which the PF_INET6 layer is about to release. 527 */ 528 NET_EPOCH_ENTER(et); 529 CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) { 530 inm = in6m_ifmultiaddr_get_inm(ifma); 531 if (inm == NULL) 532 continue; 533 in6m_disconnect_locked(inmh, inm); 534 535 if (mli->mli_version == MLD_VERSION_2) { 536 in6m_clear_recorded(inm); 537 538 /* 539 * We need to release the final reference held 540 * for issuing the INCLUDE {}. 541 */ 542 if (inm->in6m_state == MLD_LEAVING_MEMBER) { 543 inm->in6m_state = MLD_NOT_MEMBER; 544 in6m_rele_locked(inmh, inm); 545 } 546 } 547 } 548 NET_EPOCH_EXIT(et); 549 IF_ADDR_WUNLOCK(ifp); 550 MLD_UNLOCK(); 551 } 552 553 /* 554 * Hook for domifdetach. 555 * Runs after link-layer cleanup; free MLD state. 556 * 557 * SMPng: Normally called with IF_AFDATA_LOCK held. 558 */ 559 void 560 mld_domifdetach(struct ifnet *ifp) 561 { 562 563 CTR3(KTR_MLD, "%s: called for ifp %p(%s)", 564 __func__, ifp, if_name(ifp)); 565 566 MLD_LOCK(); 567 mli_delete_locked(ifp); 568 MLD_UNLOCK(); 569 } 570 571 static void 572 mli_delete_locked(const struct ifnet *ifp) 573 { 574 struct mld_ifsoftc *mli, *tmli; 575 576 CTR3(KTR_MLD, "%s: freeing mld_ifsoftc for ifp %p(%s)", 577 __func__, ifp, if_name(ifp)); 578 579 MLD_LOCK_ASSERT(); 580 581 LIST_FOREACH_SAFE(mli, &V_mli_head, mli_link, tmli) { 582 if (mli->mli_ifp == ifp) { 583 /* 584 * Free deferred General Query responses. 585 */ 586 mbufq_drain(&mli->mli_gq); 587 588 LIST_REMOVE(mli, mli_link); 589 590 free(mli, M_MLD); 591 return; 592 } 593 } 594 } 595 596 /* 597 * Process a received MLDv1 general or address-specific query. 598 * Assumes that the query header has been pulled up to sizeof(mld_hdr). 599 * 600 * NOTE: Can't be fully const correct as we temporarily embed scope ID in 601 * mld_addr. This is OK as we own the mbuf chain. 602 */ 603 static int 604 mld_v1_input_query(struct ifnet *ifp, const struct ip6_hdr *ip6, 605 /*const*/ struct mld_hdr *mld) 606 { 607 struct ifmultiaddr *ifma; 608 struct mld_ifsoftc *mli; 609 struct in6_multi *inm; 610 int is_general_query; 611 uint16_t timer; 612 #ifdef KTR 613 char ip6tbuf[INET6_ADDRSTRLEN]; 614 #endif 615 616 NET_EPOCH_ASSERT(); 617 618 is_general_query = 0; 619 620 if (!mld_v1enable) { 621 CTR3(KTR_MLD, "ignore v1 query %s on ifp %p(%s)", 622 ip6_sprintf(ip6tbuf, &mld->mld_addr), 623 ifp, if_name(ifp)); 624 return (0); 625 } 626 627 /* 628 * RFC3810 Section 6.2: MLD queries must originate from 629 * a router's link-local address. 630 */ 631 if (!IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 632 CTR3(KTR_MLD, "ignore v1 query src %s on ifp %p(%s)", 633 ip6_sprintf(ip6tbuf, &ip6->ip6_src), 634 ifp, if_name(ifp)); 635 return (0); 636 } 637 638 /* 639 * Do address field validation upfront before we accept 640 * the query. 641 */ 642 if (IN6_IS_ADDR_UNSPECIFIED(&mld->mld_addr)) { 643 /* 644 * MLDv1 General Query. 645 * If this was not sent to the all-nodes group, ignore it. 646 */ 647 struct in6_addr dst; 648 649 dst = ip6->ip6_dst; 650 in6_clearscope(&dst); 651 if (!IN6_ARE_ADDR_EQUAL(&dst, &in6addr_linklocal_allnodes)) 652 return (EINVAL); 653 is_general_query = 1; 654 } else { 655 /* 656 * Embed scope ID of receiving interface in MLD query for 657 * lookup whilst we don't hold other locks. 658 */ 659 in6_setscope(&mld->mld_addr, ifp, NULL); 660 } 661 662 IN6_MULTI_LIST_LOCK(); 663 MLD_LOCK(); 664 665 /* 666 * Switch to MLDv1 host compatibility mode. 667 */ 668 mli = MLD_IFINFO(ifp); 669 KASSERT(mli != NULL, ("%s: no mld_ifsoftc for ifp %p", __func__, ifp)); 670 mld_set_version(mli, MLD_VERSION_1); 671 672 timer = (ntohs(mld->mld_maxdelay) * MLD_FASTHZ) / MLD_TIMER_SCALE; 673 if (timer == 0) 674 timer = 1; 675 676 if (is_general_query) { 677 /* 678 * For each reporting group joined on this 679 * interface, kick the report timer. 680 */ 681 CTR2(KTR_MLD, "process v1 general query on ifp %p(%s)", 682 ifp, if_name(ifp)); 683 CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) { 684 inm = in6m_ifmultiaddr_get_inm(ifma); 685 if (inm == NULL) 686 continue; 687 mld_v1_update_group(inm, timer); 688 } 689 } else { 690 /* 691 * MLDv1 Group-Specific Query. 692 * If this is a group-specific MLDv1 query, we need only 693 * look up the single group to process it. 694 */ 695 inm = in6m_lookup_locked(ifp, &mld->mld_addr); 696 if (inm != NULL) { 697 CTR3(KTR_MLD, "process v1 query %s on ifp %p(%s)", 698 ip6_sprintf(ip6tbuf, &mld->mld_addr), 699 ifp, if_name(ifp)); 700 mld_v1_update_group(inm, timer); 701 } 702 /* XXX Clear embedded scope ID as userland won't expect it. */ 703 in6_clearscope(&mld->mld_addr); 704 } 705 706 MLD_UNLOCK(); 707 IN6_MULTI_LIST_UNLOCK(); 708 709 return (0); 710 } 711 712 /* 713 * Update the report timer on a group in response to an MLDv1 query. 714 * 715 * If we are becoming the reporting member for this group, start the timer. 716 * If we already are the reporting member for this group, and timer is 717 * below the threshold, reset it. 718 * 719 * We may be updating the group for the first time since we switched 720 * to MLDv2. If we are, then we must clear any recorded source lists, 721 * and transition to REPORTING state; the group timer is overloaded 722 * for group and group-source query responses. 723 * 724 * Unlike MLDv2, the delay per group should be jittered 725 * to avoid bursts of MLDv1 reports. 726 */ 727 static void 728 mld_v1_update_group(struct in6_multi *inm, const int timer) 729 { 730 #ifdef KTR 731 char ip6tbuf[INET6_ADDRSTRLEN]; 732 #endif 733 734 CTR4(KTR_MLD, "%s: %s/%s timer=%d", __func__, 735 ip6_sprintf(ip6tbuf, &inm->in6m_addr), 736 if_name(inm->in6m_ifp), timer); 737 738 IN6_MULTI_LIST_LOCK_ASSERT(); 739 740 switch (inm->in6m_state) { 741 case MLD_NOT_MEMBER: 742 case MLD_SILENT_MEMBER: 743 break; 744 case MLD_REPORTING_MEMBER: 745 if (inm->in6m_timer != 0 && 746 inm->in6m_timer <= timer) { 747 CTR1(KTR_MLD, "%s: REPORTING and timer running, " 748 "skipping.", __func__); 749 break; 750 } 751 /* FALLTHROUGH */ 752 case MLD_SG_QUERY_PENDING_MEMBER: 753 case MLD_G_QUERY_PENDING_MEMBER: 754 case MLD_IDLE_MEMBER: 755 case MLD_LAZY_MEMBER: 756 case MLD_AWAKENING_MEMBER: 757 CTR1(KTR_MLD, "%s: ->REPORTING", __func__); 758 inm->in6m_state = MLD_REPORTING_MEMBER; 759 inm->in6m_timer = MLD_RANDOM_DELAY(timer); 760 V_current_state_timers_running6 = 1; 761 break; 762 case MLD_SLEEPING_MEMBER: 763 CTR1(KTR_MLD, "%s: ->AWAKENING", __func__); 764 inm->in6m_state = MLD_AWAKENING_MEMBER; 765 break; 766 case MLD_LEAVING_MEMBER: 767 break; 768 } 769 } 770 771 /* 772 * Process a received MLDv2 general, group-specific or 773 * group-and-source-specific query. 774 * 775 * Assumes that mld points to a struct mldv2_query which is stored in 776 * contiguous memory. 777 * 778 * Return 0 if successful, otherwise an appropriate error code is returned. 779 */ 780 static int 781 mld_v2_input_query(struct ifnet *ifp, const struct ip6_hdr *ip6, 782 struct mbuf *m, struct mldv2_query *mld, const int off, const int icmp6len) 783 { 784 struct mld_ifsoftc *mli; 785 struct in6_multi *inm; 786 uint32_t maxdelay, nsrc, qqi; 787 int is_general_query; 788 uint16_t timer; 789 uint8_t qrv; 790 #ifdef KTR 791 char ip6tbuf[INET6_ADDRSTRLEN]; 792 #endif 793 794 NET_EPOCH_ASSERT(); 795 796 if (!mld_v2enable) { 797 CTR3(KTR_MLD, "ignore v2 query src %s on ifp %p(%s)", 798 ip6_sprintf(ip6tbuf, &ip6->ip6_src), 799 ifp, if_name(ifp)); 800 return (0); 801 } 802 803 /* 804 * RFC3810 Section 6.2: MLD queries must originate from 805 * a router's link-local address. 806 */ 807 if (!IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 808 CTR3(KTR_MLD, "ignore v1 query src %s on ifp %p(%s)", 809 ip6_sprintf(ip6tbuf, &ip6->ip6_src), 810 ifp, if_name(ifp)); 811 return (0); 812 } 813 814 is_general_query = 0; 815 816 CTR2(KTR_MLD, "input v2 query on ifp %p(%s)", ifp, if_name(ifp)); 817 818 maxdelay = ntohs(mld->mld_maxdelay); /* in 1/10ths of a second */ 819 if (maxdelay >= 32768) { 820 maxdelay = (MLD_MRC_MANT(maxdelay) | 0x1000) << 821 (MLD_MRC_EXP(maxdelay) + 3); 822 } 823 timer = (maxdelay * MLD_FASTHZ) / MLD_TIMER_SCALE; 824 if (timer == 0) 825 timer = 1; 826 827 qrv = MLD_QRV(mld->mld_misc); 828 if (qrv < 2) { 829 CTR3(KTR_MLD, "%s: clamping qrv %d to %d", __func__, 830 qrv, MLD_RV_INIT); 831 qrv = MLD_RV_INIT; 832 } 833 834 qqi = mld->mld_qqi; 835 if (qqi >= 128) { 836 qqi = MLD_QQIC_MANT(mld->mld_qqi) << 837 (MLD_QQIC_EXP(mld->mld_qqi) + 3); 838 } 839 840 nsrc = ntohs(mld->mld_numsrc); 841 if (nsrc > MLD_MAX_GS_SOURCES) 842 return (EMSGSIZE); 843 if (icmp6len < sizeof(struct mldv2_query) + 844 (nsrc * sizeof(struct in6_addr))) 845 return (EMSGSIZE); 846 847 /* 848 * Do further input validation upfront to avoid resetting timers 849 * should we need to discard this query. 850 */ 851 if (IN6_IS_ADDR_UNSPECIFIED(&mld->mld_addr)) { 852 /* 853 * A general query with a source list has undefined 854 * behaviour; discard it. 855 */ 856 if (nsrc > 0) 857 return (EINVAL); 858 is_general_query = 1; 859 } else { 860 /* 861 * Embed scope ID of receiving interface in MLD query for 862 * lookup whilst we don't hold other locks (due to KAME 863 * locking lameness). We own this mbuf chain just now. 864 */ 865 in6_setscope(&mld->mld_addr, ifp, NULL); 866 } 867 868 IN6_MULTI_LIST_LOCK(); 869 MLD_LOCK(); 870 871 mli = MLD_IFINFO(ifp); 872 KASSERT(mli != NULL, ("%s: no mld_ifsoftc for ifp %p", __func__, ifp)); 873 874 /* 875 * Discard the v2 query if we're in Compatibility Mode. 876 * The RFC is pretty clear that hosts need to stay in MLDv1 mode 877 * until the Old Version Querier Present timer expires. 878 */ 879 if (mli->mli_version != MLD_VERSION_2) 880 goto out_locked; 881 882 mld_set_version(mli, MLD_VERSION_2); 883 mli->mli_rv = qrv; 884 mli->mli_qi = qqi; 885 mli->mli_qri = maxdelay; 886 887 CTR4(KTR_MLD, "%s: qrv %d qi %d maxdelay %d", __func__, qrv, qqi, 888 maxdelay); 889 890 if (is_general_query) { 891 /* 892 * MLDv2 General Query. 893 * 894 * Schedule a current-state report on this ifp for 895 * all groups, possibly containing source lists. 896 * 897 * If there is a pending General Query response 898 * scheduled earlier than the selected delay, do 899 * not schedule any other reports. 900 * Otherwise, reset the interface timer. 901 */ 902 CTR2(KTR_MLD, "process v2 general query on ifp %p(%s)", 903 ifp, if_name(ifp)); 904 if (mli->mli_v2_timer == 0 || mli->mli_v2_timer >= timer) { 905 mli->mli_v2_timer = MLD_RANDOM_DELAY(timer); 906 V_interface_timers_running6 = 1; 907 } 908 } else { 909 /* 910 * MLDv2 Group-specific or Group-and-source-specific Query. 911 * 912 * Group-source-specific queries are throttled on 913 * a per-group basis to defeat denial-of-service attempts. 914 * Queries for groups we are not a member of on this 915 * link are simply ignored. 916 */ 917 inm = in6m_lookup_locked(ifp, &mld->mld_addr); 918 if (inm == NULL) 919 goto out_locked; 920 if (nsrc > 0) { 921 if (!ratecheck(&inm->in6m_lastgsrtv, 922 &V_mld_gsrdelay)) { 923 CTR1(KTR_MLD, "%s: GS query throttled.", 924 __func__); 925 goto out_locked; 926 } 927 } 928 CTR2(KTR_MLD, "process v2 group query on ifp %p(%s)", 929 ifp, if_name(ifp)); 930 /* 931 * If there is a pending General Query response 932 * scheduled sooner than the selected delay, no 933 * further report need be scheduled. 934 * Otherwise, prepare to respond to the 935 * group-specific or group-and-source query. 936 */ 937 if (mli->mli_v2_timer == 0 || mli->mli_v2_timer >= timer) 938 mld_v2_process_group_query(inm, mli, timer, m, mld, off); 939 940 /* XXX Clear embedded scope ID as userland won't expect it. */ 941 in6_clearscope(&mld->mld_addr); 942 } 943 944 out_locked: 945 MLD_UNLOCK(); 946 IN6_MULTI_LIST_UNLOCK(); 947 948 return (0); 949 } 950 951 /* 952 * Process a received MLDv2 group-specific or group-and-source-specific 953 * query. 954 * Return <0 if any error occurred. Currently this is ignored. 955 */ 956 static int 957 mld_v2_process_group_query(struct in6_multi *inm, struct mld_ifsoftc *mli, 958 int timer, struct mbuf *m0, struct mldv2_query *mld, const int off) 959 { 960 int retval; 961 uint16_t nsrc; 962 963 IN6_MULTI_LIST_LOCK_ASSERT(); 964 MLD_LOCK_ASSERT(); 965 966 retval = 0; 967 968 switch (inm->in6m_state) { 969 case MLD_NOT_MEMBER: 970 case MLD_SILENT_MEMBER: 971 case MLD_SLEEPING_MEMBER: 972 case MLD_LAZY_MEMBER: 973 case MLD_AWAKENING_MEMBER: 974 case MLD_IDLE_MEMBER: 975 case MLD_LEAVING_MEMBER: 976 return (retval); 977 break; 978 case MLD_REPORTING_MEMBER: 979 case MLD_G_QUERY_PENDING_MEMBER: 980 case MLD_SG_QUERY_PENDING_MEMBER: 981 break; 982 } 983 984 nsrc = ntohs(mld->mld_numsrc); 985 986 /* Length should be checked by calling function. */ 987 KASSERT((m0->m_flags & M_PKTHDR) == 0 || 988 m0->m_pkthdr.len >= off + sizeof(struct mldv2_query) + 989 nsrc * sizeof(struct in6_addr), 990 ("mldv2 packet is too short: (%d bytes < %zd bytes, m=%p)", 991 m0->m_pkthdr.len, off + sizeof(struct mldv2_query) + 992 nsrc * sizeof(struct in6_addr), m0)); 993 994 /* 995 * Deal with group-specific queries upfront. 996 * If any group query is already pending, purge any recorded 997 * source-list state if it exists, and schedule a query response 998 * for this group-specific query. 999 */ 1000 if (nsrc == 0) { 1001 if (inm->in6m_state == MLD_G_QUERY_PENDING_MEMBER || 1002 inm->in6m_state == MLD_SG_QUERY_PENDING_MEMBER) { 1003 in6m_clear_recorded(inm); 1004 timer = min(inm->in6m_timer, timer); 1005 } 1006 inm->in6m_state = MLD_G_QUERY_PENDING_MEMBER; 1007 inm->in6m_timer = MLD_RANDOM_DELAY(timer); 1008 V_current_state_timers_running6 = 1; 1009 return (retval); 1010 } 1011 1012 /* 1013 * Deal with the case where a group-and-source-specific query has 1014 * been received but a group-specific query is already pending. 1015 */ 1016 if (inm->in6m_state == MLD_G_QUERY_PENDING_MEMBER) { 1017 timer = min(inm->in6m_timer, timer); 1018 inm->in6m_timer = MLD_RANDOM_DELAY(timer); 1019 V_current_state_timers_running6 = 1; 1020 return (retval); 1021 } 1022 1023 /* 1024 * Finally, deal with the case where a group-and-source-specific 1025 * query has been received, where a response to a previous g-s-r 1026 * query exists, or none exists. 1027 * In this case, we need to parse the source-list which the Querier 1028 * has provided us with and check if we have any source list filter 1029 * entries at T1 for these sources. If we do not, there is no need 1030 * schedule a report and the query may be dropped. 1031 * If we do, we must record them and schedule a current-state 1032 * report for those sources. 1033 */ 1034 if (inm->in6m_nsrc > 0) { 1035 struct in6_addr srcaddr; 1036 int i, nrecorded; 1037 int soff; 1038 1039 soff = off + sizeof(struct mldv2_query); 1040 nrecorded = 0; 1041 for (i = 0; i < nsrc; i++) { 1042 m_copydata(m0, soff, sizeof(struct in6_addr), 1043 (caddr_t)&srcaddr); 1044 retval = in6m_record_source(inm, &srcaddr); 1045 if (retval < 0) 1046 break; 1047 nrecorded += retval; 1048 soff += sizeof(struct in6_addr); 1049 } 1050 if (nrecorded > 0) { 1051 CTR1(KTR_MLD, 1052 "%s: schedule response to SG query", __func__); 1053 inm->in6m_state = MLD_SG_QUERY_PENDING_MEMBER; 1054 inm->in6m_timer = MLD_RANDOM_DELAY(timer); 1055 V_current_state_timers_running6 = 1; 1056 } 1057 } 1058 1059 return (retval); 1060 } 1061 1062 /* 1063 * Process a received MLDv1 host membership report. 1064 * Assumes mld points to mld_hdr in pulled up mbuf chain. 1065 * 1066 * NOTE: Can't be fully const correct as we temporarily embed scope ID in 1067 * mld_addr. This is OK as we own the mbuf chain. 1068 */ 1069 static int 1070 mld_v1_input_report(struct ifnet *ifp, const struct ip6_hdr *ip6, 1071 /*const*/ struct mld_hdr *mld) 1072 { 1073 struct in6_addr src, dst; 1074 struct in6_ifaddr *ia; 1075 struct in6_multi *inm; 1076 #ifdef KTR 1077 char ip6tbuf[INET6_ADDRSTRLEN]; 1078 #endif 1079 1080 NET_EPOCH_ASSERT(); 1081 1082 if (!mld_v1enable) { 1083 CTR3(KTR_MLD, "ignore v1 report %s on ifp %p(%s)", 1084 ip6_sprintf(ip6tbuf, &mld->mld_addr), 1085 ifp, if_name(ifp)); 1086 return (0); 1087 } 1088 1089 if (ifp->if_flags & IFF_LOOPBACK) 1090 return (0); 1091 1092 /* 1093 * MLDv1 reports must originate from a host's link-local address, 1094 * or the unspecified address (when booting). 1095 */ 1096 src = ip6->ip6_src; 1097 in6_clearscope(&src); 1098 if (!IN6_IS_SCOPE_LINKLOCAL(&src) && !IN6_IS_ADDR_UNSPECIFIED(&src)) { 1099 CTR3(KTR_MLD, "ignore v1 query src %s on ifp %p(%s)", 1100 ip6_sprintf(ip6tbuf, &ip6->ip6_src), 1101 ifp, if_name(ifp)); 1102 return (EINVAL); 1103 } 1104 1105 /* 1106 * RFC2710 Section 4: MLDv1 reports must pertain to a multicast 1107 * group, and must be directed to the group itself. 1108 */ 1109 dst = ip6->ip6_dst; 1110 in6_clearscope(&dst); 1111 if (!IN6_IS_ADDR_MULTICAST(&mld->mld_addr) || 1112 !IN6_ARE_ADDR_EQUAL(&mld->mld_addr, &dst)) { 1113 CTR3(KTR_MLD, "ignore v1 query dst %s on ifp %p(%s)", 1114 ip6_sprintf(ip6tbuf, &ip6->ip6_dst), 1115 ifp, if_name(ifp)); 1116 return (EINVAL); 1117 } 1118 1119 /* 1120 * Make sure we don't hear our own membership report, as fast 1121 * leave requires knowing that we are the only member of a 1122 * group. Assume we used the link-local address if available, 1123 * otherwise look for ::. 1124 * 1125 * XXX Note that scope ID comparison is needed for the address 1126 * returned by in6ifa_ifpforlinklocal(), but SHOULD NOT be 1127 * performed for the on-wire address. 1128 */ 1129 ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 1130 if ((ia && IN6_ARE_ADDR_EQUAL(&ip6->ip6_src, IA6_IN6(ia))) || 1131 (ia == NULL && IN6_IS_ADDR_UNSPECIFIED(&src))) { 1132 if (ia != NULL) 1133 ifa_free(&ia->ia_ifa); 1134 return (0); 1135 } 1136 if (ia != NULL) 1137 ifa_free(&ia->ia_ifa); 1138 1139 CTR3(KTR_MLD, "process v1 report %s on ifp %p(%s)", 1140 ip6_sprintf(ip6tbuf, &mld->mld_addr), ifp, if_name(ifp)); 1141 1142 /* 1143 * Embed scope ID of receiving interface in MLD query for lookup 1144 * whilst we don't hold other locks (due to KAME locking lameness). 1145 */ 1146 if (!IN6_IS_ADDR_UNSPECIFIED(&mld->mld_addr)) 1147 in6_setscope(&mld->mld_addr, ifp, NULL); 1148 1149 IN6_MULTI_LIST_LOCK(); 1150 MLD_LOCK(); 1151 1152 /* 1153 * MLDv1 report suppression. 1154 * If we are a member of this group, and our membership should be 1155 * reported, and our group timer is pending or about to be reset, 1156 * stop our group timer by transitioning to the 'lazy' state. 1157 */ 1158 inm = in6m_lookup_locked(ifp, &mld->mld_addr); 1159 if (inm != NULL) { 1160 struct mld_ifsoftc *mli; 1161 1162 mli = inm->in6m_mli; 1163 KASSERT(mli != NULL, 1164 ("%s: no mli for ifp %p", __func__, ifp)); 1165 1166 /* 1167 * If we are in MLDv2 host mode, do not allow the 1168 * other host's MLDv1 report to suppress our reports. 1169 */ 1170 if (mli->mli_version == MLD_VERSION_2) 1171 goto out_locked; 1172 1173 inm->in6m_timer = 0; 1174 1175 switch (inm->in6m_state) { 1176 case MLD_NOT_MEMBER: 1177 case MLD_SILENT_MEMBER: 1178 case MLD_SLEEPING_MEMBER: 1179 break; 1180 case MLD_REPORTING_MEMBER: 1181 case MLD_IDLE_MEMBER: 1182 case MLD_AWAKENING_MEMBER: 1183 CTR3(KTR_MLD, 1184 "report suppressed for %s on ifp %p(%s)", 1185 ip6_sprintf(ip6tbuf, &mld->mld_addr), 1186 ifp, if_name(ifp)); 1187 case MLD_LAZY_MEMBER: 1188 inm->in6m_state = MLD_LAZY_MEMBER; 1189 break; 1190 case MLD_G_QUERY_PENDING_MEMBER: 1191 case MLD_SG_QUERY_PENDING_MEMBER: 1192 case MLD_LEAVING_MEMBER: 1193 break; 1194 } 1195 } 1196 1197 out_locked: 1198 MLD_UNLOCK(); 1199 IN6_MULTI_LIST_UNLOCK(); 1200 1201 /* XXX Clear embedded scope ID as userland won't expect it. */ 1202 in6_clearscope(&mld->mld_addr); 1203 1204 return (0); 1205 } 1206 1207 /* 1208 * MLD input path. 1209 * 1210 * Assume query messages which fit in a single ICMPv6 message header 1211 * have been pulled up. 1212 * Assume that userland will want to see the message, even if it 1213 * otherwise fails kernel input validation; do not free it. 1214 * Pullup may however free the mbuf chain m if it fails. 1215 * 1216 * Return IPPROTO_DONE if we freed m. Otherwise, return 0. 1217 */ 1218 int 1219 mld_input(struct mbuf **mp, int off, int icmp6len) 1220 { 1221 struct ifnet *ifp; 1222 struct ip6_hdr *ip6; 1223 struct mbuf *m; 1224 struct mld_hdr *mld; 1225 int mldlen; 1226 1227 m = *mp; 1228 CTR3(KTR_MLD, "%s: called w/mbuf (%p,%d)", __func__, m, off); 1229 1230 ifp = m->m_pkthdr.rcvif; 1231 1232 /* Pullup to appropriate size. */ 1233 if (m->m_len < off + sizeof(*mld)) { 1234 m = m_pullup(m, off + sizeof(*mld)); 1235 if (m == NULL) { 1236 ICMP6STAT_INC(icp6s_badlen); 1237 return (IPPROTO_DONE); 1238 } 1239 } 1240 mld = (struct mld_hdr *)(mtod(m, uint8_t *) + off); 1241 if (mld->mld_type == MLD_LISTENER_QUERY && 1242 icmp6len >= sizeof(struct mldv2_query)) { 1243 mldlen = sizeof(struct mldv2_query); 1244 } else { 1245 mldlen = sizeof(struct mld_hdr); 1246 } 1247 if (m->m_len < off + mldlen) { 1248 m = m_pullup(m, off + mldlen); 1249 if (m == NULL) { 1250 ICMP6STAT_INC(icp6s_badlen); 1251 return (IPPROTO_DONE); 1252 } 1253 } 1254 *mp = m; 1255 ip6 = mtod(m, struct ip6_hdr *); 1256 mld = (struct mld_hdr *)(mtod(m, uint8_t *) + off); 1257 1258 /* 1259 * Userland needs to see all of this traffic for implementing 1260 * the endpoint discovery portion of multicast routing. 1261 */ 1262 switch (mld->mld_type) { 1263 case MLD_LISTENER_QUERY: 1264 icmp6_ifstat_inc(ifp, ifs6_in_mldquery); 1265 if (icmp6len == sizeof(struct mld_hdr)) { 1266 if (mld_v1_input_query(ifp, ip6, mld) != 0) 1267 return (0); 1268 } else if (icmp6len >= sizeof(struct mldv2_query)) { 1269 if (mld_v2_input_query(ifp, ip6, m, 1270 (struct mldv2_query *)mld, off, icmp6len) != 0) 1271 return (0); 1272 } 1273 break; 1274 case MLD_LISTENER_REPORT: 1275 icmp6_ifstat_inc(ifp, ifs6_in_mldreport); 1276 if (mld_v1_input_report(ifp, ip6, mld) != 0) 1277 return (0); 1278 break; 1279 case MLDV2_LISTENER_REPORT: 1280 icmp6_ifstat_inc(ifp, ifs6_in_mldreport); 1281 break; 1282 case MLD_LISTENER_DONE: 1283 icmp6_ifstat_inc(ifp, ifs6_in_mlddone); 1284 break; 1285 default: 1286 break; 1287 } 1288 1289 return (0); 1290 } 1291 1292 /* 1293 * Fast timeout handler (global). 1294 * VIMAGE: Timeout handlers are expected to service all vimages. 1295 */ 1296 static struct callout mldfast_callout; 1297 static void 1298 mld_fasttimo(void *arg __unused) 1299 { 1300 struct epoch_tracker et; 1301 struct in6_multi_head inmh; 1302 VNET_ITERATOR_DECL(vnet_iter); 1303 1304 SLIST_INIT(&inmh); 1305 1306 NET_EPOCH_ENTER(et); 1307 VNET_LIST_RLOCK_NOSLEEP(); 1308 VNET_FOREACH(vnet_iter) { 1309 CURVNET_SET(vnet_iter); 1310 mld_fasttimo_vnet(&inmh); 1311 CURVNET_RESTORE(); 1312 } 1313 VNET_LIST_RUNLOCK_NOSLEEP(); 1314 NET_EPOCH_EXIT(et); 1315 in6m_release_list_deferred(&inmh); 1316 1317 callout_reset(&mldfast_callout, hz / MLD_FASTHZ, mld_fasttimo, NULL); 1318 } 1319 1320 /* 1321 * Fast timeout handler (per-vnet). 1322 * 1323 * VIMAGE: Assume caller has set up our curvnet. 1324 */ 1325 static void 1326 mld_fasttimo_vnet(struct in6_multi_head *inmh) 1327 { 1328 struct mbufq scq; /* State-change packets */ 1329 struct mbufq qrq; /* Query response packets */ 1330 struct ifnet *ifp; 1331 struct mld_ifsoftc *mli; 1332 struct ifmultiaddr *ifma; 1333 struct in6_multi *inm; 1334 int uri_fasthz; 1335 1336 uri_fasthz = 0; 1337 1338 /* 1339 * Quick check to see if any work needs to be done, in order to 1340 * minimize the overhead of fasttimo processing. 1341 * SMPng: XXX Unlocked reads. 1342 */ 1343 if (!V_current_state_timers_running6 && 1344 !V_interface_timers_running6 && 1345 !V_state_change_timers_running6) 1346 return; 1347 1348 IN6_MULTI_LIST_LOCK(); 1349 MLD_LOCK(); 1350 1351 /* 1352 * MLDv2 General Query response timer processing. 1353 */ 1354 if (V_interface_timers_running6) { 1355 CTR1(KTR_MLD, "%s: interface timers running", __func__); 1356 1357 V_interface_timers_running6 = 0; 1358 LIST_FOREACH(mli, &V_mli_head, mli_link) { 1359 if (mli->mli_v2_timer == 0) { 1360 /* Do nothing. */ 1361 } else if (--mli->mli_v2_timer == 0) { 1362 mld_v2_dispatch_general_query(mli); 1363 } else { 1364 V_interface_timers_running6 = 1; 1365 } 1366 } 1367 } 1368 1369 if (!V_current_state_timers_running6 && 1370 !V_state_change_timers_running6) 1371 goto out_locked; 1372 1373 V_current_state_timers_running6 = 0; 1374 V_state_change_timers_running6 = 0; 1375 1376 CTR1(KTR_MLD, "%s: state change timers running", __func__); 1377 1378 /* 1379 * MLD host report and state-change timer processing. 1380 * Note: Processing a v2 group timer may remove a node. 1381 */ 1382 LIST_FOREACH(mli, &V_mli_head, mli_link) { 1383 ifp = mli->mli_ifp; 1384 1385 if (mli->mli_version == MLD_VERSION_2) { 1386 uri_fasthz = MLD_RANDOM_DELAY(mli->mli_uri * 1387 MLD_FASTHZ); 1388 mbufq_init(&qrq, MLD_MAX_G_GS_PACKETS); 1389 mbufq_init(&scq, MLD_MAX_STATE_CHANGE_PACKETS); 1390 } 1391 1392 IF_ADDR_WLOCK(ifp); 1393 CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) { 1394 inm = in6m_ifmultiaddr_get_inm(ifma); 1395 if (inm == NULL) 1396 continue; 1397 switch (mli->mli_version) { 1398 case MLD_VERSION_1: 1399 mld_v1_process_group_timer(inmh, inm); 1400 break; 1401 case MLD_VERSION_2: 1402 mld_v2_process_group_timers(inmh, &qrq, 1403 &scq, inm, uri_fasthz); 1404 break; 1405 } 1406 } 1407 IF_ADDR_WUNLOCK(ifp); 1408 1409 switch (mli->mli_version) { 1410 case MLD_VERSION_1: 1411 /* 1412 * Transmit reports for this lifecycle. This 1413 * is done while not holding IF_ADDR_LOCK 1414 * since this can call 1415 * in6ifa_ifpforlinklocal() which locks 1416 * IF_ADDR_LOCK internally as well as 1417 * ip6_output() to transmit a packet. 1418 */ 1419 while ((inm = SLIST_FIRST(inmh)) != NULL) { 1420 SLIST_REMOVE_HEAD(inmh, in6m_defer); 1421 (void)mld_v1_transmit_report(inm, 1422 MLD_LISTENER_REPORT); 1423 } 1424 break; 1425 case MLD_VERSION_2: 1426 mld_dispatch_queue(&qrq, 0); 1427 mld_dispatch_queue(&scq, 0); 1428 break; 1429 } 1430 } 1431 1432 out_locked: 1433 MLD_UNLOCK(); 1434 IN6_MULTI_LIST_UNLOCK(); 1435 } 1436 1437 /* 1438 * Update host report group timer. 1439 * Will update the global pending timer flags. 1440 */ 1441 static void 1442 mld_v1_process_group_timer(struct in6_multi_head *inmh, struct in6_multi *inm) 1443 { 1444 int report_timer_expired; 1445 1446 IN6_MULTI_LIST_LOCK_ASSERT(); 1447 MLD_LOCK_ASSERT(); 1448 1449 if (inm->in6m_timer == 0) { 1450 report_timer_expired = 0; 1451 } else if (--inm->in6m_timer == 0) { 1452 report_timer_expired = 1; 1453 } else { 1454 V_current_state_timers_running6 = 1; 1455 return; 1456 } 1457 1458 switch (inm->in6m_state) { 1459 case MLD_NOT_MEMBER: 1460 case MLD_SILENT_MEMBER: 1461 case MLD_IDLE_MEMBER: 1462 case MLD_LAZY_MEMBER: 1463 case MLD_SLEEPING_MEMBER: 1464 case MLD_AWAKENING_MEMBER: 1465 break; 1466 case MLD_REPORTING_MEMBER: 1467 if (report_timer_expired) { 1468 inm->in6m_state = MLD_IDLE_MEMBER; 1469 SLIST_INSERT_HEAD(inmh, inm, in6m_defer); 1470 } 1471 break; 1472 case MLD_G_QUERY_PENDING_MEMBER: 1473 case MLD_SG_QUERY_PENDING_MEMBER: 1474 case MLD_LEAVING_MEMBER: 1475 break; 1476 } 1477 } 1478 1479 /* 1480 * Update a group's timers for MLDv2. 1481 * Will update the global pending timer flags. 1482 * Note: Unlocked read from mli. 1483 */ 1484 static void 1485 mld_v2_process_group_timers(struct in6_multi_head *inmh, 1486 struct mbufq *qrq, struct mbufq *scq, 1487 struct in6_multi *inm, const int uri_fasthz) 1488 { 1489 int query_response_timer_expired; 1490 int state_change_retransmit_timer_expired; 1491 #ifdef KTR 1492 char ip6tbuf[INET6_ADDRSTRLEN]; 1493 #endif 1494 1495 IN6_MULTI_LIST_LOCK_ASSERT(); 1496 MLD_LOCK_ASSERT(); 1497 1498 query_response_timer_expired = 0; 1499 state_change_retransmit_timer_expired = 0; 1500 1501 /* 1502 * During a transition from compatibility mode back to MLDv2, 1503 * a group record in REPORTING state may still have its group 1504 * timer active. This is a no-op in this function; it is easier 1505 * to deal with it here than to complicate the slow-timeout path. 1506 */ 1507 if (inm->in6m_timer == 0) { 1508 query_response_timer_expired = 0; 1509 } else if (--inm->in6m_timer == 0) { 1510 query_response_timer_expired = 1; 1511 } else { 1512 V_current_state_timers_running6 = 1; 1513 } 1514 1515 if (inm->in6m_sctimer == 0) { 1516 state_change_retransmit_timer_expired = 0; 1517 } else if (--inm->in6m_sctimer == 0) { 1518 state_change_retransmit_timer_expired = 1; 1519 } else { 1520 V_state_change_timers_running6 = 1; 1521 } 1522 1523 /* We are in fasttimo, so be quick about it. */ 1524 if (!state_change_retransmit_timer_expired && 1525 !query_response_timer_expired) 1526 return; 1527 1528 switch (inm->in6m_state) { 1529 case MLD_NOT_MEMBER: 1530 case MLD_SILENT_MEMBER: 1531 case MLD_SLEEPING_MEMBER: 1532 case MLD_LAZY_MEMBER: 1533 case MLD_AWAKENING_MEMBER: 1534 case MLD_IDLE_MEMBER: 1535 break; 1536 case MLD_G_QUERY_PENDING_MEMBER: 1537 case MLD_SG_QUERY_PENDING_MEMBER: 1538 /* 1539 * Respond to a previously pending Group-Specific 1540 * or Group-and-Source-Specific query by enqueueing 1541 * the appropriate Current-State report for 1542 * immediate transmission. 1543 */ 1544 if (query_response_timer_expired) { 1545 int retval __unused; 1546 1547 retval = mld_v2_enqueue_group_record(qrq, inm, 0, 1, 1548 (inm->in6m_state == MLD_SG_QUERY_PENDING_MEMBER), 1549 0); 1550 CTR2(KTR_MLD, "%s: enqueue record = %d", 1551 __func__, retval); 1552 inm->in6m_state = MLD_REPORTING_MEMBER; 1553 in6m_clear_recorded(inm); 1554 } 1555 /* FALLTHROUGH */ 1556 case MLD_REPORTING_MEMBER: 1557 case MLD_LEAVING_MEMBER: 1558 if (state_change_retransmit_timer_expired) { 1559 /* 1560 * State-change retransmission timer fired. 1561 * If there are any further pending retransmissions, 1562 * set the global pending state-change flag, and 1563 * reset the timer. 1564 */ 1565 if (--inm->in6m_scrv > 0) { 1566 inm->in6m_sctimer = uri_fasthz; 1567 V_state_change_timers_running6 = 1; 1568 } 1569 /* 1570 * Retransmit the previously computed state-change 1571 * report. If there are no further pending 1572 * retransmissions, the mbuf queue will be consumed. 1573 * Update T0 state to T1 as we have now sent 1574 * a state-change. 1575 */ 1576 (void)mld_v2_merge_state_changes(inm, scq); 1577 1578 in6m_commit(inm); 1579 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__, 1580 ip6_sprintf(ip6tbuf, &inm->in6m_addr), 1581 if_name(inm->in6m_ifp)); 1582 1583 /* 1584 * If we are leaving the group for good, make sure 1585 * we release MLD's reference to it. 1586 * This release must be deferred using a SLIST, 1587 * as we are called from a loop which traverses 1588 * the in_ifmultiaddr TAILQ. 1589 */ 1590 if (inm->in6m_state == MLD_LEAVING_MEMBER && 1591 inm->in6m_scrv == 0) { 1592 inm->in6m_state = MLD_NOT_MEMBER; 1593 in6m_disconnect_locked(inmh, inm); 1594 in6m_rele_locked(inmh, inm); 1595 } 1596 } 1597 break; 1598 } 1599 } 1600 1601 /* 1602 * Switch to a different version on the given interface, 1603 * as per Section 9.12. 1604 */ 1605 static void 1606 mld_set_version(struct mld_ifsoftc *mli, const int version) 1607 { 1608 int old_version_timer; 1609 1610 MLD_LOCK_ASSERT(); 1611 1612 CTR4(KTR_MLD, "%s: switching to v%d on ifp %p(%s)", __func__, 1613 version, mli->mli_ifp, if_name(mli->mli_ifp)); 1614 1615 if (version == MLD_VERSION_1) { 1616 /* 1617 * Compute the "Older Version Querier Present" timer as per 1618 * Section 9.12. 1619 */ 1620 old_version_timer = (mli->mli_rv * mli->mli_qi) + mli->mli_qri; 1621 old_version_timer *= MLD_SLOWHZ; 1622 mli->mli_v1_timer = old_version_timer; 1623 } 1624 1625 if (mli->mli_v1_timer > 0 && mli->mli_version != MLD_VERSION_1) { 1626 mli->mli_version = MLD_VERSION_1; 1627 mld_v2_cancel_link_timers(mli); 1628 } 1629 } 1630 1631 /* 1632 * Cancel pending MLDv2 timers for the given link and all groups 1633 * joined on it; state-change, general-query, and group-query timers. 1634 */ 1635 static void 1636 mld_v2_cancel_link_timers(struct mld_ifsoftc *mli) 1637 { 1638 struct epoch_tracker et; 1639 struct in6_multi_head inmh; 1640 struct ifmultiaddr *ifma; 1641 struct ifnet *ifp; 1642 struct in6_multi *inm; 1643 1644 CTR3(KTR_MLD, "%s: cancel v2 timers on ifp %p(%s)", __func__, 1645 mli->mli_ifp, if_name(mli->mli_ifp)); 1646 1647 SLIST_INIT(&inmh); 1648 IN6_MULTI_LIST_LOCK_ASSERT(); 1649 MLD_LOCK_ASSERT(); 1650 1651 /* 1652 * Fast-track this potentially expensive operation 1653 * by checking all the global 'timer pending' flags. 1654 */ 1655 if (!V_interface_timers_running6 && 1656 !V_state_change_timers_running6 && 1657 !V_current_state_timers_running6) 1658 return; 1659 1660 mli->mli_v2_timer = 0; 1661 1662 ifp = mli->mli_ifp; 1663 1664 IF_ADDR_WLOCK(ifp); 1665 NET_EPOCH_ENTER(et); 1666 CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) { 1667 inm = in6m_ifmultiaddr_get_inm(ifma); 1668 if (inm == NULL) 1669 continue; 1670 switch (inm->in6m_state) { 1671 case MLD_NOT_MEMBER: 1672 case MLD_SILENT_MEMBER: 1673 case MLD_IDLE_MEMBER: 1674 case MLD_LAZY_MEMBER: 1675 case MLD_SLEEPING_MEMBER: 1676 case MLD_AWAKENING_MEMBER: 1677 break; 1678 case MLD_LEAVING_MEMBER: 1679 /* 1680 * If we are leaving the group and switching 1681 * version, we need to release the final 1682 * reference held for issuing the INCLUDE {}. 1683 */ 1684 if (inm->in6m_refcount == 1) 1685 in6m_disconnect_locked(&inmh, inm); 1686 in6m_rele_locked(&inmh, inm); 1687 /* FALLTHROUGH */ 1688 case MLD_G_QUERY_PENDING_MEMBER: 1689 case MLD_SG_QUERY_PENDING_MEMBER: 1690 in6m_clear_recorded(inm); 1691 /* FALLTHROUGH */ 1692 case MLD_REPORTING_MEMBER: 1693 inm->in6m_sctimer = 0; 1694 inm->in6m_timer = 0; 1695 inm->in6m_state = MLD_REPORTING_MEMBER; 1696 /* 1697 * Free any pending MLDv2 state-change records. 1698 */ 1699 mbufq_drain(&inm->in6m_scq); 1700 break; 1701 } 1702 } 1703 NET_EPOCH_EXIT(et); 1704 IF_ADDR_WUNLOCK(ifp); 1705 in6m_release_list_deferred(&inmh); 1706 } 1707 1708 /* 1709 * Global slowtimo handler. 1710 * VIMAGE: Timeout handlers are expected to service all vimages. 1711 */ 1712 static struct callout mldslow_callout; 1713 static void 1714 mld_slowtimo(void *arg __unused) 1715 { 1716 VNET_ITERATOR_DECL(vnet_iter); 1717 1718 VNET_LIST_RLOCK_NOSLEEP(); 1719 VNET_FOREACH(vnet_iter) { 1720 CURVNET_SET(vnet_iter); 1721 mld_slowtimo_vnet(); 1722 CURVNET_RESTORE(); 1723 } 1724 VNET_LIST_RUNLOCK_NOSLEEP(); 1725 1726 callout_reset(&mldslow_callout, hz / MLD_SLOWHZ, mld_slowtimo, NULL); 1727 } 1728 1729 /* 1730 * Per-vnet slowtimo handler. 1731 */ 1732 static void 1733 mld_slowtimo_vnet(void) 1734 { 1735 struct mld_ifsoftc *mli; 1736 1737 MLD_LOCK(); 1738 1739 LIST_FOREACH(mli, &V_mli_head, mli_link) { 1740 mld_v1_process_querier_timers(mli); 1741 } 1742 1743 MLD_UNLOCK(); 1744 } 1745 1746 /* 1747 * Update the Older Version Querier Present timers for a link. 1748 * See Section 9.12 of RFC 3810. 1749 */ 1750 static void 1751 mld_v1_process_querier_timers(struct mld_ifsoftc *mli) 1752 { 1753 1754 MLD_LOCK_ASSERT(); 1755 1756 if (mli->mli_version != MLD_VERSION_2 && --mli->mli_v1_timer == 0) { 1757 /* 1758 * MLDv1 Querier Present timer expired; revert to MLDv2. 1759 */ 1760 CTR5(KTR_MLD, 1761 "%s: transition from v%d -> v%d on %p(%s)", 1762 __func__, mli->mli_version, MLD_VERSION_2, 1763 mli->mli_ifp, if_name(mli->mli_ifp)); 1764 mli->mli_version = MLD_VERSION_2; 1765 } 1766 } 1767 1768 /* 1769 * Transmit an MLDv1 report immediately. 1770 */ 1771 static int 1772 mld_v1_transmit_report(struct in6_multi *in6m, const int type) 1773 { 1774 struct ifnet *ifp; 1775 struct in6_ifaddr *ia; 1776 struct ip6_hdr *ip6; 1777 struct mbuf *mh, *md; 1778 struct mld_hdr *mld; 1779 1780 NET_EPOCH_ASSERT(); 1781 IN6_MULTI_LIST_LOCK_ASSERT(); 1782 MLD_LOCK_ASSERT(); 1783 1784 ifp = in6m->in6m_ifp; 1785 /* in process of being freed */ 1786 if (ifp == NULL) 1787 return (0); 1788 ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 1789 /* ia may be NULL if link-local address is tentative. */ 1790 1791 mh = m_gethdr(M_NOWAIT, MT_DATA); 1792 if (mh == NULL) { 1793 if (ia != NULL) 1794 ifa_free(&ia->ia_ifa); 1795 return (ENOMEM); 1796 } 1797 md = m_get(M_NOWAIT, MT_DATA); 1798 if (md == NULL) { 1799 m_free(mh); 1800 if (ia != NULL) 1801 ifa_free(&ia->ia_ifa); 1802 return (ENOMEM); 1803 } 1804 mh->m_next = md; 1805 1806 /* 1807 * FUTURE: Consider increasing alignment by ETHER_HDR_LEN, so 1808 * that ether_output() does not need to allocate another mbuf 1809 * for the header in the most common case. 1810 */ 1811 M_ALIGN(mh, sizeof(struct ip6_hdr)); 1812 mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld_hdr); 1813 mh->m_len = sizeof(struct ip6_hdr); 1814 1815 ip6 = mtod(mh, struct ip6_hdr *); 1816 ip6->ip6_flow = 0; 1817 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 1818 ip6->ip6_vfc |= IPV6_VERSION; 1819 ip6->ip6_nxt = IPPROTO_ICMPV6; 1820 ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any; 1821 ip6->ip6_dst = in6m->in6m_addr; 1822 1823 md->m_len = sizeof(struct mld_hdr); 1824 mld = mtod(md, struct mld_hdr *); 1825 mld->mld_type = type; 1826 mld->mld_code = 0; 1827 mld->mld_cksum = 0; 1828 mld->mld_maxdelay = 0; 1829 mld->mld_reserved = 0; 1830 mld->mld_addr = in6m->in6m_addr; 1831 in6_clearscope(&mld->mld_addr); 1832 mld->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6, 1833 sizeof(struct ip6_hdr), sizeof(struct mld_hdr)); 1834 1835 mld_save_context(mh, ifp); 1836 mh->m_flags |= M_MLDV1; 1837 1838 mld_dispatch_packet(mh); 1839 1840 if (ia != NULL) 1841 ifa_free(&ia->ia_ifa); 1842 return (0); 1843 } 1844 1845 /* 1846 * Process a state change from the upper layer for the given IPv6 group. 1847 * 1848 * Each socket holds a reference on the in_multi in its own ip_moptions. 1849 * The socket layer will have made the necessary updates to.the group 1850 * state, it is now up to MLD to issue a state change report if there 1851 * has been any change between T0 (when the last state-change was issued) 1852 * and T1 (now). 1853 * 1854 * We use the MLDv2 state machine at group level. The MLd module 1855 * however makes the decision as to which MLD protocol version to speak. 1856 * A state change *from* INCLUDE {} always means an initial join. 1857 * A state change *to* INCLUDE {} always means a final leave. 1858 * 1859 * If delay is non-zero, and the state change is an initial multicast 1860 * join, the state change report will be delayed by 'delay' ticks 1861 * in units of MLD_FASTHZ if MLDv1 is active on the link; otherwise 1862 * the initial MLDv2 state change report will be delayed by whichever 1863 * is sooner, a pending state-change timer or delay itself. 1864 * 1865 * VIMAGE: curvnet should have been set by caller, as this routine 1866 * is called from the socket option handlers. 1867 */ 1868 int 1869 mld_change_state(struct in6_multi *inm, const int delay) 1870 { 1871 struct mld_ifsoftc *mli; 1872 struct ifnet *ifp; 1873 int error; 1874 1875 IN6_MULTI_LIST_LOCK_ASSERT(); 1876 1877 error = 0; 1878 1879 /* 1880 * Check if the in6_multi has already been disconnected. 1881 */ 1882 if (inm->in6m_ifp == NULL) { 1883 CTR1(KTR_MLD, "%s: inm is disconnected", __func__); 1884 return (0); 1885 } 1886 1887 /* 1888 * Try to detect if the upper layer just asked us to change state 1889 * for an interface which has now gone away. 1890 */ 1891 KASSERT(inm->in6m_ifma != NULL, ("%s: no ifma", __func__)); 1892 ifp = inm->in6m_ifma->ifma_ifp; 1893 if (ifp == NULL) 1894 return (0); 1895 /* 1896 * Sanity check that netinet6's notion of ifp is the 1897 * same as net's. 1898 */ 1899 KASSERT(inm->in6m_ifp == ifp, ("%s: bad ifp", __func__)); 1900 1901 MLD_LOCK(); 1902 mli = MLD_IFINFO(ifp); 1903 KASSERT(mli != NULL, ("%s: no mld_ifsoftc for ifp %p", __func__, ifp)); 1904 1905 /* 1906 * If we detect a state transition to or from MCAST_UNDEFINED 1907 * for this group, then we are starting or finishing an MLD 1908 * life cycle for this group. 1909 */ 1910 if (inm->in6m_st[1].iss_fmode != inm->in6m_st[0].iss_fmode) { 1911 CTR3(KTR_MLD, "%s: inm transition %d -> %d", __func__, 1912 inm->in6m_st[0].iss_fmode, inm->in6m_st[1].iss_fmode); 1913 if (inm->in6m_st[0].iss_fmode == MCAST_UNDEFINED) { 1914 CTR1(KTR_MLD, "%s: initial join", __func__); 1915 error = mld_initial_join(inm, mli, delay); 1916 goto out_locked; 1917 } else if (inm->in6m_st[1].iss_fmode == MCAST_UNDEFINED) { 1918 CTR1(KTR_MLD, "%s: final leave", __func__); 1919 mld_final_leave(inm, mli); 1920 goto out_locked; 1921 } 1922 } else { 1923 CTR1(KTR_MLD, "%s: filter set change", __func__); 1924 } 1925 1926 error = mld_handle_state_change(inm, mli); 1927 1928 out_locked: 1929 MLD_UNLOCK(); 1930 return (error); 1931 } 1932 1933 /* 1934 * Perform the initial join for an MLD group. 1935 * 1936 * When joining a group: 1937 * If the group should have its MLD traffic suppressed, do nothing. 1938 * MLDv1 starts sending MLDv1 host membership reports. 1939 * MLDv2 will schedule an MLDv2 state-change report containing the 1940 * initial state of the membership. 1941 * 1942 * If the delay argument is non-zero, then we must delay sending the 1943 * initial state change for delay ticks (in units of MLD_FASTHZ). 1944 */ 1945 static int 1946 mld_initial_join(struct in6_multi *inm, struct mld_ifsoftc *mli, 1947 const int delay) 1948 { 1949 struct epoch_tracker et; 1950 struct ifnet *ifp; 1951 struct mbufq *mq; 1952 int error, retval, syncstates; 1953 int odelay; 1954 #ifdef KTR 1955 char ip6tbuf[INET6_ADDRSTRLEN]; 1956 #endif 1957 1958 CTR4(KTR_MLD, "%s: initial join %s on ifp %p(%s)", 1959 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr), 1960 inm->in6m_ifp, if_name(inm->in6m_ifp)); 1961 1962 error = 0; 1963 syncstates = 1; 1964 1965 ifp = inm->in6m_ifp; 1966 1967 IN6_MULTI_LIST_LOCK_ASSERT(); 1968 MLD_LOCK_ASSERT(); 1969 1970 KASSERT(mli && mli->mli_ifp == ifp, ("%s: inconsistent ifp", __func__)); 1971 1972 /* 1973 * Groups joined on loopback or marked as 'not reported', 1974 * enter the MLD_SILENT_MEMBER state and 1975 * are never reported in any protocol exchanges. 1976 * All other groups enter the appropriate state machine 1977 * for the version in use on this link. 1978 * A link marked as MLIF_SILENT causes MLD to be completely 1979 * disabled for the link. 1980 */ 1981 if ((ifp->if_flags & IFF_LOOPBACK) || 1982 (mli->mli_flags & MLIF_SILENT) || 1983 !mld_is_addr_reported(&inm->in6m_addr)) { 1984 CTR1(KTR_MLD, 1985 "%s: not kicking state machine for silent group", __func__); 1986 inm->in6m_state = MLD_SILENT_MEMBER; 1987 inm->in6m_timer = 0; 1988 } else { 1989 /* 1990 * Deal with overlapping in_multi lifecycle. 1991 * If this group was LEAVING, then make sure 1992 * we drop the reference we picked up to keep the 1993 * group around for the final INCLUDE {} enqueue. 1994 */ 1995 if (mli->mli_version == MLD_VERSION_2 && 1996 inm->in6m_state == MLD_LEAVING_MEMBER) { 1997 inm->in6m_refcount--; 1998 MPASS(inm->in6m_refcount > 0); 1999 } 2000 inm->in6m_state = MLD_REPORTING_MEMBER; 2001 2002 switch (mli->mli_version) { 2003 case MLD_VERSION_1: 2004 /* 2005 * If a delay was provided, only use it if 2006 * it is greater than the delay normally 2007 * used for an MLDv1 state change report, 2008 * and delay sending the initial MLDv1 report 2009 * by not transitioning to the IDLE state. 2010 */ 2011 odelay = MLD_RANDOM_DELAY(MLD_V1_MAX_RI * MLD_FASTHZ); 2012 if (delay) { 2013 inm->in6m_timer = max(delay, odelay); 2014 V_current_state_timers_running6 = 1; 2015 } else { 2016 inm->in6m_state = MLD_IDLE_MEMBER; 2017 NET_EPOCH_ENTER(et); 2018 error = mld_v1_transmit_report(inm, 2019 MLD_LISTENER_REPORT); 2020 NET_EPOCH_EXIT(et); 2021 if (error == 0) { 2022 inm->in6m_timer = odelay; 2023 V_current_state_timers_running6 = 1; 2024 } 2025 } 2026 break; 2027 2028 case MLD_VERSION_2: 2029 /* 2030 * Defer update of T0 to T1, until the first copy 2031 * of the state change has been transmitted. 2032 */ 2033 syncstates = 0; 2034 2035 /* 2036 * Immediately enqueue a State-Change Report for 2037 * this interface, freeing any previous reports. 2038 * Don't kick the timers if there is nothing to do, 2039 * or if an error occurred. 2040 */ 2041 mq = &inm->in6m_scq; 2042 mbufq_drain(mq); 2043 retval = mld_v2_enqueue_group_record(mq, inm, 1, 2044 0, 0, (mli->mli_flags & MLIF_USEALLOW)); 2045 CTR2(KTR_MLD, "%s: enqueue record = %d", 2046 __func__, retval); 2047 if (retval <= 0) { 2048 error = retval * -1; 2049 break; 2050 } 2051 2052 /* 2053 * Schedule transmission of pending state-change 2054 * report up to RV times for this link. The timer 2055 * will fire at the next mld_fasttimo (~200ms), 2056 * giving us an opportunity to merge the reports. 2057 * 2058 * If a delay was provided to this function, only 2059 * use this delay if sooner than the existing one. 2060 */ 2061 KASSERT(mli->mli_rv > 1, 2062 ("%s: invalid robustness %d", __func__, 2063 mli->mli_rv)); 2064 inm->in6m_scrv = mli->mli_rv; 2065 if (delay) { 2066 if (inm->in6m_sctimer > 1) { 2067 inm->in6m_sctimer = 2068 min(inm->in6m_sctimer, delay); 2069 } else 2070 inm->in6m_sctimer = delay; 2071 } else 2072 inm->in6m_sctimer = 1; 2073 V_state_change_timers_running6 = 1; 2074 2075 error = 0; 2076 break; 2077 } 2078 } 2079 2080 /* 2081 * Only update the T0 state if state change is atomic, 2082 * i.e. we don't need to wait for a timer to fire before we 2083 * can consider the state change to have been communicated. 2084 */ 2085 if (syncstates) { 2086 in6m_commit(inm); 2087 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__, 2088 ip6_sprintf(ip6tbuf, &inm->in6m_addr), 2089 if_name(inm->in6m_ifp)); 2090 } 2091 2092 return (error); 2093 } 2094 2095 /* 2096 * Issue an intermediate state change during the life-cycle. 2097 */ 2098 static int 2099 mld_handle_state_change(struct in6_multi *inm, struct mld_ifsoftc *mli) 2100 { 2101 struct ifnet *ifp; 2102 int retval; 2103 #ifdef KTR 2104 char ip6tbuf[INET6_ADDRSTRLEN]; 2105 #endif 2106 2107 CTR4(KTR_MLD, "%s: state change for %s on ifp %p(%s)", 2108 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr), 2109 inm->in6m_ifp, if_name(inm->in6m_ifp)); 2110 2111 ifp = inm->in6m_ifp; 2112 2113 IN6_MULTI_LIST_LOCK_ASSERT(); 2114 MLD_LOCK_ASSERT(); 2115 2116 KASSERT(mli && mli->mli_ifp == ifp, 2117 ("%s: inconsistent ifp", __func__)); 2118 2119 if ((ifp->if_flags & IFF_LOOPBACK) || 2120 (mli->mli_flags & MLIF_SILENT) || 2121 !mld_is_addr_reported(&inm->in6m_addr) || 2122 (mli->mli_version != MLD_VERSION_2)) { 2123 if (!mld_is_addr_reported(&inm->in6m_addr)) { 2124 CTR1(KTR_MLD, 2125 "%s: not kicking state machine for silent group", __func__); 2126 } 2127 CTR1(KTR_MLD, "%s: nothing to do", __func__); 2128 in6m_commit(inm); 2129 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__, 2130 ip6_sprintf(ip6tbuf, &inm->in6m_addr), 2131 if_name(inm->in6m_ifp)); 2132 return (0); 2133 } 2134 2135 mbufq_drain(&inm->in6m_scq); 2136 2137 retval = mld_v2_enqueue_group_record(&inm->in6m_scq, inm, 1, 0, 0, 2138 (mli->mli_flags & MLIF_USEALLOW)); 2139 CTR2(KTR_MLD, "%s: enqueue record = %d", __func__, retval); 2140 if (retval <= 0) 2141 return (-retval); 2142 2143 /* 2144 * If record(s) were enqueued, start the state-change 2145 * report timer for this group. 2146 */ 2147 inm->in6m_scrv = mli->mli_rv; 2148 inm->in6m_sctimer = 1; 2149 V_state_change_timers_running6 = 1; 2150 2151 return (0); 2152 } 2153 2154 /* 2155 * Perform the final leave for a multicast address. 2156 * 2157 * When leaving a group: 2158 * MLDv1 sends a DONE message, if and only if we are the reporter. 2159 * MLDv2 enqueues a state-change report containing a transition 2160 * to INCLUDE {} for immediate transmission. 2161 */ 2162 static void 2163 mld_final_leave(struct in6_multi *inm, struct mld_ifsoftc *mli) 2164 { 2165 struct epoch_tracker et; 2166 int syncstates; 2167 #ifdef KTR 2168 char ip6tbuf[INET6_ADDRSTRLEN]; 2169 #endif 2170 2171 syncstates = 1; 2172 2173 CTR4(KTR_MLD, "%s: final leave %s on ifp %p(%s)", 2174 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr), 2175 inm->in6m_ifp, if_name(inm->in6m_ifp)); 2176 2177 IN6_MULTI_LIST_LOCK_ASSERT(); 2178 MLD_LOCK_ASSERT(); 2179 2180 switch (inm->in6m_state) { 2181 case MLD_NOT_MEMBER: 2182 case MLD_SILENT_MEMBER: 2183 case MLD_LEAVING_MEMBER: 2184 /* Already leaving or left; do nothing. */ 2185 CTR1(KTR_MLD, 2186 "%s: not kicking state machine for silent group", __func__); 2187 break; 2188 case MLD_REPORTING_MEMBER: 2189 case MLD_IDLE_MEMBER: 2190 case MLD_G_QUERY_PENDING_MEMBER: 2191 case MLD_SG_QUERY_PENDING_MEMBER: 2192 if (mli->mli_version == MLD_VERSION_1) { 2193 #ifdef INVARIANTS 2194 if (inm->in6m_state == MLD_G_QUERY_PENDING_MEMBER || 2195 inm->in6m_state == MLD_SG_QUERY_PENDING_MEMBER) 2196 panic("%s: MLDv2 state reached, not MLDv2 mode", 2197 __func__); 2198 #endif 2199 NET_EPOCH_ENTER(et); 2200 mld_v1_transmit_report(inm, MLD_LISTENER_DONE); 2201 NET_EPOCH_EXIT(et); 2202 inm->in6m_state = MLD_NOT_MEMBER; 2203 V_current_state_timers_running6 = 1; 2204 } else if (mli->mli_version == MLD_VERSION_2) { 2205 /* 2206 * Stop group timer and all pending reports. 2207 * Immediately enqueue a state-change report 2208 * TO_IN {} to be sent on the next fast timeout, 2209 * giving us an opportunity to merge reports. 2210 */ 2211 mbufq_drain(&inm->in6m_scq); 2212 inm->in6m_timer = 0; 2213 inm->in6m_scrv = mli->mli_rv; 2214 CTR4(KTR_MLD, "%s: Leaving %s/%s with %d " 2215 "pending retransmissions.", __func__, 2216 ip6_sprintf(ip6tbuf, &inm->in6m_addr), 2217 if_name(inm->in6m_ifp), inm->in6m_scrv); 2218 if (inm->in6m_scrv == 0) { 2219 inm->in6m_state = MLD_NOT_MEMBER; 2220 inm->in6m_sctimer = 0; 2221 } else { 2222 int retval __diagused; 2223 2224 in6m_acquire_locked(inm); 2225 2226 retval = mld_v2_enqueue_group_record( 2227 &inm->in6m_scq, inm, 1, 0, 0, 2228 (mli->mli_flags & MLIF_USEALLOW)); 2229 KASSERT(retval != 0, 2230 ("%s: enqueue record = %d", __func__, 2231 retval)); 2232 2233 inm->in6m_state = MLD_LEAVING_MEMBER; 2234 inm->in6m_sctimer = 1; 2235 V_state_change_timers_running6 = 1; 2236 syncstates = 0; 2237 } 2238 break; 2239 } 2240 break; 2241 case MLD_LAZY_MEMBER: 2242 case MLD_SLEEPING_MEMBER: 2243 case MLD_AWAKENING_MEMBER: 2244 /* Our reports are suppressed; do nothing. */ 2245 break; 2246 } 2247 2248 if (syncstates) { 2249 in6m_commit(inm); 2250 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__, 2251 ip6_sprintf(ip6tbuf, &inm->in6m_addr), 2252 if_name(inm->in6m_ifp)); 2253 inm->in6m_st[1].iss_fmode = MCAST_UNDEFINED; 2254 CTR3(KTR_MLD, "%s: T1 now MCAST_UNDEFINED for %p/%s", 2255 __func__, &inm->in6m_addr, if_name(inm->in6m_ifp)); 2256 } 2257 } 2258 2259 /* 2260 * Enqueue an MLDv2 group record to the given output queue. 2261 * 2262 * If is_state_change is zero, a current-state record is appended. 2263 * If is_state_change is non-zero, a state-change report is appended. 2264 * 2265 * If is_group_query is non-zero, an mbuf packet chain is allocated. 2266 * If is_group_query is zero, and if there is a packet with free space 2267 * at the tail of the queue, it will be appended to providing there 2268 * is enough free space. 2269 * Otherwise a new mbuf packet chain is allocated. 2270 * 2271 * If is_source_query is non-zero, each source is checked to see if 2272 * it was recorded for a Group-Source query, and will be omitted if 2273 * it is not both in-mode and recorded. 2274 * 2275 * If use_block_allow is non-zero, state change reports for initial join 2276 * and final leave, on an inclusive mode group with a source list, will be 2277 * rewritten to use the ALLOW_NEW and BLOCK_OLD record types, respectively. 2278 * 2279 * The function will attempt to allocate leading space in the packet 2280 * for the IPv6+ICMP headers to be prepended without fragmenting the chain. 2281 * 2282 * If successful the size of all data appended to the queue is returned, 2283 * otherwise an error code less than zero is returned, or zero if 2284 * no record(s) were appended. 2285 */ 2286 static int 2287 mld_v2_enqueue_group_record(struct mbufq *mq, struct in6_multi *inm, 2288 const int is_state_change, const int is_group_query, 2289 const int is_source_query, const int use_block_allow) 2290 { 2291 struct mldv2_record mr; 2292 struct mldv2_record *pmr; 2293 struct ifnet *ifp; 2294 struct ip6_msource *ims, *nims; 2295 struct mbuf *m0, *m, *md; 2296 int is_filter_list_change; 2297 int minrec0len, m0srcs, msrcs, nbytes, off; 2298 int record_has_sources; 2299 int now; 2300 int type; 2301 uint8_t mode; 2302 #ifdef KTR 2303 char ip6tbuf[INET6_ADDRSTRLEN]; 2304 #endif 2305 2306 IN6_MULTI_LIST_LOCK_ASSERT(); 2307 2308 ifp = inm->in6m_ifp; 2309 is_filter_list_change = 0; 2310 m = NULL; 2311 m0 = NULL; 2312 m0srcs = 0; 2313 msrcs = 0; 2314 nbytes = 0; 2315 nims = NULL; 2316 record_has_sources = 1; 2317 pmr = NULL; 2318 type = MLD_DO_NOTHING; 2319 mode = inm->in6m_st[1].iss_fmode; 2320 2321 /* 2322 * If we did not transition out of ASM mode during t0->t1, 2323 * and there are no source nodes to process, we can skip 2324 * the generation of source records. 2325 */ 2326 if (inm->in6m_st[0].iss_asm > 0 && inm->in6m_st[1].iss_asm > 0 && 2327 inm->in6m_nsrc == 0) 2328 record_has_sources = 0; 2329 2330 if (is_state_change) { 2331 /* 2332 * Queue a state change record. 2333 * If the mode did not change, and there are non-ASM 2334 * listeners or source filters present, 2335 * we potentially need to issue two records for the group. 2336 * If there are ASM listeners, and there was no filter 2337 * mode transition of any kind, do nothing. 2338 * 2339 * If we are transitioning to MCAST_UNDEFINED, we need 2340 * not send any sources. A transition to/from this state is 2341 * considered inclusive with some special treatment. 2342 * 2343 * If we are rewriting initial joins/leaves to use 2344 * ALLOW/BLOCK, and the group's membership is inclusive, 2345 * we need to send sources in all cases. 2346 */ 2347 if (mode != inm->in6m_st[0].iss_fmode) { 2348 if (mode == MCAST_EXCLUDE) { 2349 CTR1(KTR_MLD, "%s: change to EXCLUDE", 2350 __func__); 2351 type = MLD_CHANGE_TO_EXCLUDE_MODE; 2352 } else { 2353 CTR1(KTR_MLD, "%s: change to INCLUDE", 2354 __func__); 2355 if (use_block_allow) { 2356 /* 2357 * XXX 2358 * Here we're interested in state 2359 * edges either direction between 2360 * MCAST_UNDEFINED and MCAST_INCLUDE. 2361 * Perhaps we should just check 2362 * the group state, rather than 2363 * the filter mode. 2364 */ 2365 if (mode == MCAST_UNDEFINED) { 2366 type = MLD_BLOCK_OLD_SOURCES; 2367 } else { 2368 type = MLD_ALLOW_NEW_SOURCES; 2369 } 2370 } else { 2371 type = MLD_CHANGE_TO_INCLUDE_MODE; 2372 if (mode == MCAST_UNDEFINED) 2373 record_has_sources = 0; 2374 } 2375 } 2376 } else { 2377 if (record_has_sources) { 2378 is_filter_list_change = 1; 2379 } else { 2380 type = MLD_DO_NOTHING; 2381 } 2382 } 2383 } else { 2384 /* 2385 * Queue a current state record. 2386 */ 2387 if (mode == MCAST_EXCLUDE) { 2388 type = MLD_MODE_IS_EXCLUDE; 2389 } else if (mode == MCAST_INCLUDE) { 2390 type = MLD_MODE_IS_INCLUDE; 2391 KASSERT(inm->in6m_st[1].iss_asm == 0, 2392 ("%s: inm %p is INCLUDE but ASM count is %d", 2393 __func__, inm, inm->in6m_st[1].iss_asm)); 2394 } 2395 } 2396 2397 /* 2398 * Generate the filter list changes using a separate function. 2399 */ 2400 if (is_filter_list_change) 2401 return (mld_v2_enqueue_filter_change(mq, inm)); 2402 2403 if (type == MLD_DO_NOTHING) { 2404 CTR3(KTR_MLD, "%s: nothing to do for %s/%s", 2405 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr), 2406 if_name(inm->in6m_ifp)); 2407 return (0); 2408 } 2409 2410 /* 2411 * If any sources are present, we must be able to fit at least 2412 * one in the trailing space of the tail packet's mbuf, 2413 * ideally more. 2414 */ 2415 minrec0len = sizeof(struct mldv2_record); 2416 if (record_has_sources) 2417 minrec0len += sizeof(struct in6_addr); 2418 2419 CTR4(KTR_MLD, "%s: queueing %s for %s/%s", __func__, 2420 mld_rec_type_to_str(type), 2421 ip6_sprintf(ip6tbuf, &inm->in6m_addr), 2422 if_name(inm->in6m_ifp)); 2423 2424 /* 2425 * Check if we have a packet in the tail of the queue for this 2426 * group into which the first group record for this group will fit. 2427 * Otherwise allocate a new packet. 2428 * Always allocate leading space for IP6+RA+ICMPV6+REPORT. 2429 * Note: Group records for G/GSR query responses MUST be sent 2430 * in their own packet. 2431 */ 2432 m0 = mbufq_last(mq); 2433 if (!is_group_query && 2434 m0 != NULL && 2435 (m0->m_pkthdr.vt_nrecs + 1 <= MLD_V2_REPORT_MAXRECS) && 2436 (m0->m_pkthdr.len + minrec0len) < 2437 (ifp->if_mtu - MLD_MTUSPACE)) { 2438 m0srcs = (ifp->if_mtu - m0->m_pkthdr.len - 2439 sizeof(struct mldv2_record)) / 2440 sizeof(struct in6_addr); 2441 m = m0; 2442 CTR1(KTR_MLD, "%s: use existing packet", __func__); 2443 } else { 2444 if (mbufq_full(mq)) { 2445 CTR1(KTR_MLD, "%s: outbound queue full", __func__); 2446 return (-ENOMEM); 2447 } 2448 m = NULL; 2449 m0srcs = (ifp->if_mtu - MLD_MTUSPACE - 2450 sizeof(struct mldv2_record)) / sizeof(struct in6_addr); 2451 if (!is_state_change && !is_group_query) 2452 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 2453 if (m == NULL) 2454 m = m_gethdr(M_NOWAIT, MT_DATA); 2455 if (m == NULL) 2456 return (-ENOMEM); 2457 2458 mld_save_context(m, ifp); 2459 2460 CTR1(KTR_MLD, "%s: allocated first packet", __func__); 2461 } 2462 2463 /* 2464 * Append group record. 2465 * If we have sources, we don't know how many yet. 2466 */ 2467 mr.mr_type = type; 2468 mr.mr_datalen = 0; 2469 mr.mr_numsrc = 0; 2470 mr.mr_addr = inm->in6m_addr; 2471 in6_clearscope(&mr.mr_addr); 2472 if (!m_append(m, sizeof(struct mldv2_record), (void *)&mr)) { 2473 if (m != m0) 2474 m_freem(m); 2475 CTR1(KTR_MLD, "%s: m_append() failed.", __func__); 2476 return (-ENOMEM); 2477 } 2478 nbytes += sizeof(struct mldv2_record); 2479 2480 /* 2481 * Append as many sources as will fit in the first packet. 2482 * If we are appending to a new packet, the chain allocation 2483 * may potentially use clusters; use m_getptr() in this case. 2484 * If we are appending to an existing packet, we need to obtain 2485 * a pointer to the group record after m_append(), in case a new 2486 * mbuf was allocated. 2487 * 2488 * Only append sources which are in-mode at t1. If we are 2489 * transitioning to MCAST_UNDEFINED state on the group, and 2490 * use_block_allow is zero, do not include source entries. 2491 * Otherwise, we need to include this source in the report. 2492 * 2493 * Only report recorded sources in our filter set when responding 2494 * to a group-source query. 2495 */ 2496 if (record_has_sources) { 2497 if (m == m0) { 2498 md = m_last(m); 2499 pmr = (struct mldv2_record *)(mtod(md, uint8_t *) + 2500 md->m_len - nbytes); 2501 } else { 2502 md = m_getptr(m, 0, &off); 2503 pmr = (struct mldv2_record *)(mtod(md, uint8_t *) + 2504 off); 2505 } 2506 msrcs = 0; 2507 RB_FOREACH_SAFE(ims, ip6_msource_tree, &inm->in6m_srcs, 2508 nims) { 2509 CTR2(KTR_MLD, "%s: visit node %s", __func__, 2510 ip6_sprintf(ip6tbuf, &ims->im6s_addr)); 2511 now = im6s_get_mode(inm, ims, 1); 2512 CTR2(KTR_MLD, "%s: node is %d", __func__, now); 2513 if ((now != mode) || 2514 (now == mode && 2515 (!use_block_allow && mode == MCAST_UNDEFINED))) { 2516 CTR1(KTR_MLD, "%s: skip node", __func__); 2517 continue; 2518 } 2519 if (is_source_query && ims->im6s_stp == 0) { 2520 CTR1(KTR_MLD, "%s: skip unrecorded node", 2521 __func__); 2522 continue; 2523 } 2524 CTR1(KTR_MLD, "%s: append node", __func__); 2525 if (!m_append(m, sizeof(struct in6_addr), 2526 (void *)&ims->im6s_addr)) { 2527 if (m != m0) 2528 m_freem(m); 2529 CTR1(KTR_MLD, "%s: m_append() failed.", 2530 __func__); 2531 return (-ENOMEM); 2532 } 2533 nbytes += sizeof(struct in6_addr); 2534 ++msrcs; 2535 if (msrcs == m0srcs) 2536 break; 2537 } 2538 CTR2(KTR_MLD, "%s: msrcs is %d this packet", __func__, 2539 msrcs); 2540 pmr->mr_numsrc = htons(msrcs); 2541 nbytes += (msrcs * sizeof(struct in6_addr)); 2542 } 2543 2544 if (is_source_query && msrcs == 0) { 2545 CTR1(KTR_MLD, "%s: no recorded sources to report", __func__); 2546 if (m != m0) 2547 m_freem(m); 2548 return (0); 2549 } 2550 2551 /* 2552 * We are good to go with first packet. 2553 */ 2554 if (m != m0) { 2555 CTR1(KTR_MLD, "%s: enqueueing first packet", __func__); 2556 m->m_pkthdr.vt_nrecs = 1; 2557 mbufq_enqueue(mq, m); 2558 } else 2559 m->m_pkthdr.vt_nrecs++; 2560 2561 /* 2562 * No further work needed if no source list in packet(s). 2563 */ 2564 if (!record_has_sources) 2565 return (nbytes); 2566 2567 /* 2568 * Whilst sources remain to be announced, we need to allocate 2569 * a new packet and fill out as many sources as will fit. 2570 * Always try for a cluster first. 2571 */ 2572 while (nims != NULL) { 2573 if (mbufq_full(mq)) { 2574 CTR1(KTR_MLD, "%s: outbound queue full", __func__); 2575 return (-ENOMEM); 2576 } 2577 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 2578 if (m == NULL) 2579 m = m_gethdr(M_NOWAIT, MT_DATA); 2580 if (m == NULL) 2581 return (-ENOMEM); 2582 mld_save_context(m, ifp); 2583 md = m_getptr(m, 0, &off); 2584 pmr = (struct mldv2_record *)(mtod(md, uint8_t *) + off); 2585 CTR1(KTR_MLD, "%s: allocated next packet", __func__); 2586 2587 if (!m_append(m, sizeof(struct mldv2_record), (void *)&mr)) { 2588 if (m != m0) 2589 m_freem(m); 2590 CTR1(KTR_MLD, "%s: m_append() failed.", __func__); 2591 return (-ENOMEM); 2592 } 2593 m->m_pkthdr.vt_nrecs = 1; 2594 nbytes += sizeof(struct mldv2_record); 2595 2596 m0srcs = (ifp->if_mtu - MLD_MTUSPACE - 2597 sizeof(struct mldv2_record)) / sizeof(struct in6_addr); 2598 2599 msrcs = 0; 2600 RB_FOREACH_FROM(ims, ip6_msource_tree, nims) { 2601 CTR2(KTR_MLD, "%s: visit node %s", 2602 __func__, ip6_sprintf(ip6tbuf, &ims->im6s_addr)); 2603 now = im6s_get_mode(inm, ims, 1); 2604 if ((now != mode) || 2605 (now == mode && 2606 (!use_block_allow && mode == MCAST_UNDEFINED))) { 2607 CTR1(KTR_MLD, "%s: skip node", __func__); 2608 continue; 2609 } 2610 if (is_source_query && ims->im6s_stp == 0) { 2611 CTR1(KTR_MLD, "%s: skip unrecorded node", 2612 __func__); 2613 continue; 2614 } 2615 CTR1(KTR_MLD, "%s: append node", __func__); 2616 if (!m_append(m, sizeof(struct in6_addr), 2617 (void *)&ims->im6s_addr)) { 2618 if (m != m0) 2619 m_freem(m); 2620 CTR1(KTR_MLD, "%s: m_append() failed.", 2621 __func__); 2622 return (-ENOMEM); 2623 } 2624 ++msrcs; 2625 if (msrcs == m0srcs) 2626 break; 2627 } 2628 pmr->mr_numsrc = htons(msrcs); 2629 nbytes += (msrcs * sizeof(struct in6_addr)); 2630 2631 CTR1(KTR_MLD, "%s: enqueueing next packet", __func__); 2632 mbufq_enqueue(mq, m); 2633 } 2634 2635 return (nbytes); 2636 } 2637 2638 /* 2639 * Type used to mark record pass completion. 2640 * We exploit the fact we can cast to this easily from the 2641 * current filter modes on each ip_msource node. 2642 */ 2643 typedef enum { 2644 REC_NONE = 0x00, /* MCAST_UNDEFINED */ 2645 REC_ALLOW = 0x01, /* MCAST_INCLUDE */ 2646 REC_BLOCK = 0x02, /* MCAST_EXCLUDE */ 2647 REC_FULL = REC_ALLOW | REC_BLOCK 2648 } rectype_t; 2649 2650 /* 2651 * Enqueue an MLDv2 filter list change to the given output queue. 2652 * 2653 * Source list filter state is held in an RB-tree. When the filter list 2654 * for a group is changed without changing its mode, we need to compute 2655 * the deltas between T0 and T1 for each source in the filter set, 2656 * and enqueue the appropriate ALLOW_NEW/BLOCK_OLD records. 2657 * 2658 * As we may potentially queue two record types, and the entire R-B tree 2659 * needs to be walked at once, we break this out into its own function 2660 * so we can generate a tightly packed queue of packets. 2661 * 2662 * XXX This could be written to only use one tree walk, although that makes 2663 * serializing into the mbuf chains a bit harder. For now we do two walks 2664 * which makes things easier on us, and it may or may not be harder on 2665 * the L2 cache. 2666 * 2667 * If successful the size of all data appended to the queue is returned, 2668 * otherwise an error code less than zero is returned, or zero if 2669 * no record(s) were appended. 2670 */ 2671 static int 2672 mld_v2_enqueue_filter_change(struct mbufq *mq, struct in6_multi *inm) 2673 { 2674 static const int MINRECLEN = 2675 sizeof(struct mldv2_record) + sizeof(struct in6_addr); 2676 struct ifnet *ifp; 2677 struct mldv2_record mr; 2678 struct mldv2_record *pmr; 2679 struct ip6_msource *ims, *nims; 2680 struct mbuf *m, *m0, *md; 2681 int m0srcs, nbytes, npbytes, off, rsrcs, schanged; 2682 uint8_t mode, now, then; 2683 rectype_t crt, drt, nrt; 2684 #ifdef KTR 2685 int nallow, nblock; 2686 char ip6tbuf[INET6_ADDRSTRLEN]; 2687 #endif 2688 2689 IN6_MULTI_LIST_LOCK_ASSERT(); 2690 2691 if (inm->in6m_nsrc == 0 || 2692 (inm->in6m_st[0].iss_asm > 0 && inm->in6m_st[1].iss_asm > 0)) 2693 return (0); 2694 2695 ifp = inm->in6m_ifp; /* interface */ 2696 mode = inm->in6m_st[1].iss_fmode; /* filter mode at t1 */ 2697 crt = REC_NONE; /* current group record type */ 2698 drt = REC_NONE; /* mask of completed group record types */ 2699 nrt = REC_NONE; /* record type for current node */ 2700 m0srcs = 0; /* # source which will fit in current mbuf chain */ 2701 npbytes = 0; /* # of bytes appended this packet */ 2702 nbytes = 0; /* # of bytes appended to group's state-change queue */ 2703 rsrcs = 0; /* # sources encoded in current record */ 2704 schanged = 0; /* # nodes encoded in overall filter change */ 2705 #ifdef KTR 2706 nallow = 0; /* # of source entries in ALLOW_NEW */ 2707 nblock = 0; /* # of source entries in BLOCK_OLD */ 2708 #endif 2709 nims = NULL; /* next tree node pointer */ 2710 2711 /* 2712 * For each possible filter record mode. 2713 * The first kind of source we encounter tells us which 2714 * is the first kind of record we start appending. 2715 * If a node transitioned to UNDEFINED at t1, its mode is treated 2716 * as the inverse of the group's filter mode. 2717 */ 2718 while (drt != REC_FULL) { 2719 do { 2720 m0 = mbufq_last(mq); 2721 if (m0 != NULL && 2722 (m0->m_pkthdr.vt_nrecs + 1 <= 2723 MLD_V2_REPORT_MAXRECS) && 2724 (m0->m_pkthdr.len + MINRECLEN) < 2725 (ifp->if_mtu - MLD_MTUSPACE)) { 2726 m = m0; 2727 m0srcs = (ifp->if_mtu - m0->m_pkthdr.len - 2728 sizeof(struct mldv2_record)) / 2729 sizeof(struct in6_addr); 2730 CTR1(KTR_MLD, 2731 "%s: use previous packet", __func__); 2732 } else { 2733 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 2734 if (m == NULL) 2735 m = m_gethdr(M_NOWAIT, MT_DATA); 2736 if (m == NULL) { 2737 CTR1(KTR_MLD, 2738 "%s: m_get*() failed", __func__); 2739 return (-ENOMEM); 2740 } 2741 m->m_pkthdr.vt_nrecs = 0; 2742 mld_save_context(m, ifp); 2743 m0srcs = (ifp->if_mtu - MLD_MTUSPACE - 2744 sizeof(struct mldv2_record)) / 2745 sizeof(struct in6_addr); 2746 npbytes = 0; 2747 CTR1(KTR_MLD, 2748 "%s: allocated new packet", __func__); 2749 } 2750 /* 2751 * Append the MLD group record header to the 2752 * current packet's data area. 2753 * Recalculate pointer to free space for next 2754 * group record, in case m_append() allocated 2755 * a new mbuf or cluster. 2756 */ 2757 memset(&mr, 0, sizeof(mr)); 2758 mr.mr_addr = inm->in6m_addr; 2759 in6_clearscope(&mr.mr_addr); 2760 if (!m_append(m, sizeof(mr), (void *)&mr)) { 2761 if (m != m0) 2762 m_freem(m); 2763 CTR1(KTR_MLD, 2764 "%s: m_append() failed", __func__); 2765 return (-ENOMEM); 2766 } 2767 npbytes += sizeof(struct mldv2_record); 2768 if (m != m0) { 2769 /* new packet; offset in chain */ 2770 md = m_getptr(m, npbytes - 2771 sizeof(struct mldv2_record), &off); 2772 pmr = (struct mldv2_record *)(mtod(md, 2773 uint8_t *) + off); 2774 } else { 2775 /* current packet; offset from last append */ 2776 md = m_last(m); 2777 pmr = (struct mldv2_record *)(mtod(md, 2778 uint8_t *) + md->m_len - 2779 sizeof(struct mldv2_record)); 2780 } 2781 /* 2782 * Begin walking the tree for this record type 2783 * pass, or continue from where we left off 2784 * previously if we had to allocate a new packet. 2785 * Only report deltas in-mode at t1. 2786 * We need not report included sources as allowed 2787 * if we are in inclusive mode on the group, 2788 * however the converse is not true. 2789 */ 2790 rsrcs = 0; 2791 if (nims == NULL) { 2792 nims = RB_MIN(ip6_msource_tree, 2793 &inm->in6m_srcs); 2794 } 2795 RB_FOREACH_FROM(ims, ip6_msource_tree, nims) { 2796 CTR2(KTR_MLD, "%s: visit node %s", __func__, 2797 ip6_sprintf(ip6tbuf, &ims->im6s_addr)); 2798 now = im6s_get_mode(inm, ims, 1); 2799 then = im6s_get_mode(inm, ims, 0); 2800 CTR3(KTR_MLD, "%s: mode: t0 %d, t1 %d", 2801 __func__, then, now); 2802 if (now == then) { 2803 CTR1(KTR_MLD, 2804 "%s: skip unchanged", __func__); 2805 continue; 2806 } 2807 if (mode == MCAST_EXCLUDE && 2808 now == MCAST_INCLUDE) { 2809 CTR1(KTR_MLD, 2810 "%s: skip IN src on EX group", 2811 __func__); 2812 continue; 2813 } 2814 nrt = (rectype_t)now; 2815 if (nrt == REC_NONE) 2816 nrt = (rectype_t)(~mode & REC_FULL); 2817 if (schanged++ == 0) { 2818 crt = nrt; 2819 } else if (crt != nrt) 2820 continue; 2821 if (!m_append(m, sizeof(struct in6_addr), 2822 (void *)&ims->im6s_addr)) { 2823 if (m != m0) 2824 m_freem(m); 2825 CTR1(KTR_MLD, 2826 "%s: m_append() failed", __func__); 2827 return (-ENOMEM); 2828 } 2829 #ifdef KTR 2830 nallow += !!(crt == REC_ALLOW); 2831 nblock += !!(crt == REC_BLOCK); 2832 #endif 2833 if (++rsrcs == m0srcs) 2834 break; 2835 } 2836 /* 2837 * If we did not append any tree nodes on this 2838 * pass, back out of allocations. 2839 */ 2840 if (rsrcs == 0) { 2841 npbytes -= sizeof(struct mldv2_record); 2842 if (m != m0) { 2843 CTR1(KTR_MLD, 2844 "%s: m_free(m)", __func__); 2845 m_freem(m); 2846 } else { 2847 CTR1(KTR_MLD, 2848 "%s: m_adj(m, -mr)", __func__); 2849 m_adj(m, -((int)sizeof( 2850 struct mldv2_record))); 2851 } 2852 continue; 2853 } 2854 npbytes += (rsrcs * sizeof(struct in6_addr)); 2855 if (crt == REC_ALLOW) 2856 pmr->mr_type = MLD_ALLOW_NEW_SOURCES; 2857 else if (crt == REC_BLOCK) 2858 pmr->mr_type = MLD_BLOCK_OLD_SOURCES; 2859 pmr->mr_numsrc = htons(rsrcs); 2860 /* 2861 * Count the new group record, and enqueue this 2862 * packet if it wasn't already queued. 2863 */ 2864 m->m_pkthdr.vt_nrecs++; 2865 if (m != m0) 2866 mbufq_enqueue(mq, m); 2867 nbytes += npbytes; 2868 } while (nims != NULL); 2869 drt |= crt; 2870 crt = (~crt & REC_FULL); 2871 } 2872 2873 CTR3(KTR_MLD, "%s: queued %d ALLOW_NEW, %d BLOCK_OLD", __func__, 2874 nallow, nblock); 2875 2876 return (nbytes); 2877 } 2878 2879 static int 2880 mld_v2_merge_state_changes(struct in6_multi *inm, struct mbufq *scq) 2881 { 2882 struct mbufq *gq; 2883 struct mbuf *m; /* pending state-change */ 2884 struct mbuf *m0; /* copy of pending state-change */ 2885 struct mbuf *mt; /* last state-change in packet */ 2886 int docopy, domerge; 2887 u_int recslen; 2888 2889 docopy = 0; 2890 domerge = 0; 2891 recslen = 0; 2892 2893 IN6_MULTI_LIST_LOCK_ASSERT(); 2894 MLD_LOCK_ASSERT(); 2895 2896 /* 2897 * If there are further pending retransmissions, make a writable 2898 * copy of each queued state-change message before merging. 2899 */ 2900 if (inm->in6m_scrv > 0) 2901 docopy = 1; 2902 2903 gq = &inm->in6m_scq; 2904 #ifdef KTR 2905 if (mbufq_first(gq) == NULL) { 2906 CTR2(KTR_MLD, "%s: WARNING: queue for inm %p is empty", 2907 __func__, inm); 2908 } 2909 #endif 2910 2911 m = mbufq_first(gq); 2912 while (m != NULL) { 2913 /* 2914 * Only merge the report into the current packet if 2915 * there is sufficient space to do so; an MLDv2 report 2916 * packet may only contain 65,535 group records. 2917 * Always use a simple mbuf chain concatentation to do this, 2918 * as large state changes for single groups may have 2919 * allocated clusters. 2920 */ 2921 domerge = 0; 2922 mt = mbufq_last(scq); 2923 if (mt != NULL) { 2924 recslen = m_length(m, NULL); 2925 2926 if ((mt->m_pkthdr.vt_nrecs + 2927 m->m_pkthdr.vt_nrecs <= 2928 MLD_V2_REPORT_MAXRECS) && 2929 (mt->m_pkthdr.len + recslen <= 2930 (inm->in6m_ifp->if_mtu - MLD_MTUSPACE))) 2931 domerge = 1; 2932 } 2933 2934 if (!domerge && mbufq_full(gq)) { 2935 CTR2(KTR_MLD, 2936 "%s: outbound queue full, skipping whole packet %p", 2937 __func__, m); 2938 mt = m->m_nextpkt; 2939 if (!docopy) 2940 m_freem(m); 2941 m = mt; 2942 continue; 2943 } 2944 2945 if (!docopy) { 2946 CTR2(KTR_MLD, "%s: dequeueing %p", __func__, m); 2947 m0 = mbufq_dequeue(gq); 2948 m = m0->m_nextpkt; 2949 } else { 2950 CTR2(KTR_MLD, "%s: copying %p", __func__, m); 2951 m0 = m_dup(m, M_NOWAIT); 2952 if (m0 == NULL) 2953 return (ENOMEM); 2954 m0->m_nextpkt = NULL; 2955 m = m->m_nextpkt; 2956 } 2957 2958 if (!domerge) { 2959 CTR3(KTR_MLD, "%s: queueing %p to scq %p)", 2960 __func__, m0, scq); 2961 mbufq_enqueue(scq, m0); 2962 } else { 2963 struct mbuf *mtl; /* last mbuf of packet mt */ 2964 2965 CTR3(KTR_MLD, "%s: merging %p with ifscq tail %p)", 2966 __func__, m0, mt); 2967 2968 mtl = m_last(mt); 2969 m0->m_flags &= ~M_PKTHDR; 2970 mt->m_pkthdr.len += recslen; 2971 mt->m_pkthdr.vt_nrecs += 2972 m0->m_pkthdr.vt_nrecs; 2973 2974 mtl->m_next = m0; 2975 } 2976 } 2977 2978 return (0); 2979 } 2980 2981 /* 2982 * Respond to a pending MLDv2 General Query. 2983 */ 2984 static void 2985 mld_v2_dispatch_general_query(struct mld_ifsoftc *mli) 2986 { 2987 struct ifmultiaddr *ifma; 2988 struct ifnet *ifp; 2989 struct in6_multi *inm; 2990 int retval __unused; 2991 2992 NET_EPOCH_ASSERT(); 2993 IN6_MULTI_LIST_LOCK_ASSERT(); 2994 MLD_LOCK_ASSERT(); 2995 2996 KASSERT(mli->mli_version == MLD_VERSION_2, 2997 ("%s: called when version %d", __func__, mli->mli_version)); 2998 2999 /* 3000 * Check that there are some packets queued. If so, send them first. 3001 * For large number of groups the reply to general query can take 3002 * many packets, we should finish sending them before starting of 3003 * queuing the new reply. 3004 */ 3005 if (mbufq_len(&mli->mli_gq) != 0) 3006 goto send; 3007 3008 ifp = mli->mli_ifp; 3009 3010 CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) { 3011 inm = in6m_ifmultiaddr_get_inm(ifma); 3012 if (inm == NULL) 3013 continue; 3014 KASSERT(ifp == inm->in6m_ifp, 3015 ("%s: inconsistent ifp", __func__)); 3016 3017 switch (inm->in6m_state) { 3018 case MLD_NOT_MEMBER: 3019 case MLD_SILENT_MEMBER: 3020 break; 3021 case MLD_REPORTING_MEMBER: 3022 case MLD_IDLE_MEMBER: 3023 case MLD_LAZY_MEMBER: 3024 case MLD_SLEEPING_MEMBER: 3025 case MLD_AWAKENING_MEMBER: 3026 inm->in6m_state = MLD_REPORTING_MEMBER; 3027 retval = mld_v2_enqueue_group_record(&mli->mli_gq, 3028 inm, 0, 0, 0, 0); 3029 CTR2(KTR_MLD, "%s: enqueue record = %d", 3030 __func__, retval); 3031 break; 3032 case MLD_G_QUERY_PENDING_MEMBER: 3033 case MLD_SG_QUERY_PENDING_MEMBER: 3034 case MLD_LEAVING_MEMBER: 3035 break; 3036 } 3037 } 3038 3039 send: 3040 mld_dispatch_queue(&mli->mli_gq, MLD_MAX_RESPONSE_BURST); 3041 3042 /* 3043 * Slew transmission of bursts over 500ms intervals. 3044 */ 3045 if (mbufq_first(&mli->mli_gq) != NULL) { 3046 mli->mli_v2_timer = 1 + MLD_RANDOM_DELAY( 3047 MLD_RESPONSE_BURST_INTERVAL); 3048 V_interface_timers_running6 = 1; 3049 } 3050 } 3051 3052 /* 3053 * Transmit the next pending message in the output queue. 3054 * 3055 * VIMAGE: Needs to store/restore vnet pointer on a per-mbuf-chain basis. 3056 * MRT: Nothing needs to be done, as MLD traffic is always local to 3057 * a link and uses a link-scope multicast address. 3058 */ 3059 static void 3060 mld_dispatch_packet(struct mbuf *m) 3061 { 3062 struct ip6_moptions im6o; 3063 struct ifnet *ifp; 3064 struct ifnet *oifp; 3065 struct mbuf *m0; 3066 struct mbuf *md; 3067 struct ip6_hdr *ip6; 3068 struct mld_hdr *mld; 3069 int error; 3070 int off; 3071 int type; 3072 uint32_t ifindex; 3073 3074 CTR2(KTR_MLD, "%s: transmit %p", __func__, m); 3075 NET_EPOCH_ASSERT(); 3076 3077 /* 3078 * Set VNET image pointer from enqueued mbuf chain 3079 * before doing anything else. Whilst we use interface 3080 * indexes to guard against interface detach, they are 3081 * unique to each VIMAGE and must be retrieved. 3082 */ 3083 ifindex = mld_restore_context(m); 3084 3085 /* 3086 * Check if the ifnet still exists. This limits the scope of 3087 * any race in the absence of a global ifp lock for low cost 3088 * (an array lookup). 3089 */ 3090 ifp = ifnet_byindex(ifindex); 3091 if (ifp == NULL) { 3092 CTR3(KTR_MLD, "%s: dropped %p as ifindex %u went away.", 3093 __func__, m, ifindex); 3094 m_freem(m); 3095 IP6STAT_INC(ip6s_noroute); 3096 goto out; 3097 } 3098 3099 im6o.im6o_multicast_hlim = 1; 3100 im6o.im6o_multicast_loop = (V_ip6_mrouter != NULL); 3101 im6o.im6o_multicast_ifp = ifp; 3102 3103 if (m->m_flags & M_MLDV1) { 3104 m0 = m; 3105 } else { 3106 m0 = mld_v2_encap_report(ifp, m); 3107 if (m0 == NULL) { 3108 CTR2(KTR_MLD, "%s: dropped %p", __func__, m); 3109 IP6STAT_INC(ip6s_odropped); 3110 goto out; 3111 } 3112 } 3113 3114 mld_scrub_context(m0); 3115 m_clrprotoflags(m); 3116 m0->m_pkthdr.rcvif = V_loif; 3117 3118 ip6 = mtod(m0, struct ip6_hdr *); 3119 #if 0 3120 (void)in6_setscope(&ip6->ip6_dst, ifp, NULL); /* XXX LOR */ 3121 #else 3122 /* 3123 * XXX XXX Break some KPI rules to prevent an LOR which would 3124 * occur if we called in6_setscope() at transmission. 3125 * See comments at top of file. 3126 */ 3127 MLD_EMBEDSCOPE(&ip6->ip6_dst, ifp->if_index); 3128 #endif 3129 3130 /* 3131 * Retrieve the ICMPv6 type before handoff to ip6_output(), 3132 * so we can bump the stats. 3133 */ 3134 md = m_getptr(m0, sizeof(struct ip6_hdr), &off); 3135 mld = (struct mld_hdr *)(mtod(md, uint8_t *) + off); 3136 type = mld->mld_type; 3137 3138 oifp = NULL; 3139 error = ip6_output(m0, &mld_po, NULL, IPV6_UNSPECSRC, &im6o, 3140 &oifp, NULL); 3141 if (error) { 3142 CTR3(KTR_MLD, "%s: ip6_output(%p) = %d", __func__, m0, error); 3143 goto out; 3144 } 3145 ICMP6STAT_INC(icp6s_outhist[type]); 3146 if (oifp != NULL) { 3147 icmp6_ifstat_inc(oifp, ifs6_out_msg); 3148 switch (type) { 3149 case MLD_LISTENER_REPORT: 3150 case MLDV2_LISTENER_REPORT: 3151 icmp6_ifstat_inc(oifp, ifs6_out_mldreport); 3152 break; 3153 case MLD_LISTENER_DONE: 3154 icmp6_ifstat_inc(oifp, ifs6_out_mlddone); 3155 break; 3156 } 3157 } 3158 out: 3159 return; 3160 } 3161 3162 /* 3163 * Encapsulate an MLDv2 report. 3164 * 3165 * KAME IPv6 requires that hop-by-hop options be passed separately, 3166 * and that the IPv6 header be prepended in a separate mbuf. 3167 * 3168 * Returns a pointer to the new mbuf chain head, or NULL if the 3169 * allocation failed. 3170 */ 3171 static struct mbuf * 3172 mld_v2_encap_report(struct ifnet *ifp, struct mbuf *m) 3173 { 3174 struct mbuf *mh; 3175 struct mldv2_report *mld; 3176 struct ip6_hdr *ip6; 3177 struct in6_ifaddr *ia; 3178 int mldreclen; 3179 3180 KASSERT(ifp != NULL, ("%s: null ifp", __func__)); 3181 KASSERT((m->m_flags & M_PKTHDR), 3182 ("%s: mbuf chain %p is !M_PKTHDR", __func__, m)); 3183 3184 /* 3185 * RFC3590: OK to send as :: or tentative during DAD. 3186 */ 3187 NET_EPOCH_ASSERT(); 3188 ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 3189 if (ia == NULL) 3190 CTR1(KTR_MLD, "%s: warning: ia is NULL", __func__); 3191 3192 mh = m_gethdr(M_NOWAIT, MT_DATA); 3193 if (mh == NULL) { 3194 if (ia != NULL) 3195 ifa_free(&ia->ia_ifa); 3196 m_freem(m); 3197 return (NULL); 3198 } 3199 M_ALIGN(mh, sizeof(struct ip6_hdr) + sizeof(struct mldv2_report)); 3200 3201 mldreclen = m_length(m, NULL); 3202 CTR2(KTR_MLD, "%s: mldreclen is %d", __func__, mldreclen); 3203 3204 mh->m_len = sizeof(struct ip6_hdr) + sizeof(struct mldv2_report); 3205 mh->m_pkthdr.len = sizeof(struct ip6_hdr) + 3206 sizeof(struct mldv2_report) + mldreclen; 3207 3208 ip6 = mtod(mh, struct ip6_hdr *); 3209 ip6->ip6_flow = 0; 3210 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 3211 ip6->ip6_vfc |= IPV6_VERSION; 3212 ip6->ip6_nxt = IPPROTO_ICMPV6; 3213 ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any; 3214 if (ia != NULL) 3215 ifa_free(&ia->ia_ifa); 3216 ip6->ip6_dst = in6addr_linklocal_allv2routers; 3217 /* scope ID will be set in netisr */ 3218 3219 mld = (struct mldv2_report *)(ip6 + 1); 3220 mld->mld_type = MLDV2_LISTENER_REPORT; 3221 mld->mld_code = 0; 3222 mld->mld_cksum = 0; 3223 mld->mld_v2_reserved = 0; 3224 mld->mld_v2_numrecs = htons(m->m_pkthdr.vt_nrecs); 3225 m->m_pkthdr.vt_nrecs = 0; 3226 3227 mh->m_next = m; 3228 mld->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6, 3229 sizeof(struct ip6_hdr), sizeof(struct mldv2_report) + mldreclen); 3230 return (mh); 3231 } 3232 3233 #ifdef KTR 3234 static char * 3235 mld_rec_type_to_str(const int type) 3236 { 3237 3238 switch (type) { 3239 case MLD_CHANGE_TO_EXCLUDE_MODE: 3240 return "TO_EX"; 3241 break; 3242 case MLD_CHANGE_TO_INCLUDE_MODE: 3243 return "TO_IN"; 3244 break; 3245 case MLD_MODE_IS_EXCLUDE: 3246 return "MODE_EX"; 3247 break; 3248 case MLD_MODE_IS_INCLUDE: 3249 return "MODE_IN"; 3250 break; 3251 case MLD_ALLOW_NEW_SOURCES: 3252 return "ALLOW_NEW"; 3253 break; 3254 case MLD_BLOCK_OLD_SOURCES: 3255 return "BLOCK_OLD"; 3256 break; 3257 default: 3258 break; 3259 } 3260 return "unknown"; 3261 } 3262 #endif 3263 3264 static void 3265 mld_init(void *unused __unused) 3266 { 3267 3268 CTR1(KTR_MLD, "%s: initializing", __func__); 3269 MLD_LOCK_INIT(); 3270 3271 ip6_initpktopts(&mld_po); 3272 mld_po.ip6po_hlim = 1; 3273 mld_po.ip6po_hbh = &mld_ra.hbh; 3274 mld_po.ip6po_prefer_tempaddr = IP6PO_TEMPADDR_NOTPREFER; 3275 mld_po.ip6po_flags = IP6PO_DONTFRAG; 3276 3277 callout_init(&mldslow_callout, 1); 3278 callout_reset(&mldslow_callout, hz / MLD_SLOWHZ, mld_slowtimo, NULL); 3279 callout_init(&mldfast_callout, 1); 3280 callout_reset(&mldfast_callout, hz / MLD_FASTHZ, mld_fasttimo, NULL); 3281 } 3282 SYSINIT(mld_init, SI_SUB_PROTO_MC, SI_ORDER_MIDDLE, mld_init, NULL); 3283 3284 static void 3285 mld_uninit(void *unused __unused) 3286 { 3287 3288 CTR1(KTR_MLD, "%s: tearing down", __func__); 3289 callout_drain(&mldslow_callout); 3290 callout_drain(&mldfast_callout); 3291 MLD_LOCK_DESTROY(); 3292 } 3293 SYSUNINIT(mld_uninit, SI_SUB_PROTO_MC, SI_ORDER_MIDDLE, mld_uninit, NULL); 3294 3295 static void 3296 vnet_mld_init(const void *unused __unused) 3297 { 3298 3299 CTR1(KTR_MLD, "%s: initializing", __func__); 3300 3301 LIST_INIT(&V_mli_head); 3302 } 3303 VNET_SYSINIT(vnet_mld_init, SI_SUB_PROTO_MC, SI_ORDER_ANY, vnet_mld_init, 3304 NULL); 3305 3306 static void 3307 vnet_mld_uninit(const void *unused __unused) 3308 { 3309 3310 /* This can happen if we shutdown the network stack. */ 3311 CTR1(KTR_MLD, "%s: tearing down", __func__); 3312 } 3313 VNET_SYSUNINIT(vnet_mld_uninit, SI_SUB_PROTO_MC, SI_ORDER_ANY, vnet_mld_uninit, 3314 NULL); 3315 3316 static int 3317 mld_modevent(module_t mod, int type, void *unused __unused) 3318 { 3319 3320 switch (type) { 3321 case MOD_LOAD: 3322 case MOD_UNLOAD: 3323 break; 3324 default: 3325 return (EOPNOTSUPP); 3326 } 3327 return (0); 3328 } 3329 3330 static moduledata_t mld_mod = { 3331 "mld", 3332 mld_modevent, 3333 0 3334 }; 3335 DECLARE_MODULE(mld, mld_mod, SI_SUB_PROTO_MC, SI_ORDER_ANY); 3336