FreeBSD/Linux Kernel Cross Reference
sys/netinet6/mld6.c
1 /*-
2 * Copyright (c) 2009 Bruce Simpson.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 * 3. The name of the author may not be used to endorse or promote
13 * products derived from this software without specific prior written
14 * permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $KAME: mld6.c,v 1.27 2001/04/04 05:17:30 itojun Exp $
29 */
30
31 /*-
32 * Copyright (c) 1988 Stephen Deering.
33 * Copyright (c) 1992, 1993
34 * The Regents of the University of California. All rights reserved.
35 *
36 * This code is derived from software contributed to Berkeley by
37 * Stephen Deering of Stanford University.
38 *
39 * Redistribution and use in source and binary forms, with or without
40 * modification, are permitted provided that the following conditions
41 * are met:
42 * 1. Redistributions of source code must retain the above copyright
43 * notice, this list of conditions and the following disclaimer.
44 * 2. Redistributions in binary form must reproduce the above copyright
45 * notice, this list of conditions and the following disclaimer in the
46 * documentation and/or other materials provided with the distribution.
47 * 4. Neither the name of the University nor the names of its contributors
48 * may be used to endorse or promote products derived from this software
49 * without specific prior written permission.
50 *
51 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
52 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
53 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
54 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
55 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
56 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
57 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
58 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
59 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
60 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
61 * SUCH DAMAGE.
62 *
63 * @(#)igmp.c 8.1 (Berkeley) 7/19/93
64 */
65
66 #include <sys/cdefs.h>
67 __FBSDID("$FreeBSD: releng/9.0/sys/netinet6/mld6.c 225096 2011-08-22 23:39:40Z pluknet $");
68
69 #include "opt_inet.h"
70 #include "opt_inet6.h"
71
72 #include <sys/param.h>
73 #include <sys/systm.h>
74 #include <sys/mbuf.h>
75 #include <sys/socket.h>
76 #include <sys/protosw.h>
77 #include <sys/sysctl.h>
78 #include <sys/kernel.h>
79 #include <sys/callout.h>
80 #include <sys/malloc.h>
81 #include <sys/module.h>
82 #include <sys/ktr.h>
83
84 #include <net/if.h>
85 #include <net/route.h>
86 #include <net/vnet.h>
87
88 #include <netinet/in.h>
89 #include <netinet/in_var.h>
90 #include <netinet6/in6_var.h>
91 #include <netinet/ip6.h>
92 #include <netinet6/ip6_var.h>
93 #include <netinet6/scope6_var.h>
94 #include <netinet/icmp6.h>
95 #include <netinet6/mld6.h>
96 #include <netinet6/mld6_var.h>
97
98 #include <security/mac/mac_framework.h>
99
100 #ifndef KTR_MLD
101 #define KTR_MLD KTR_INET6
102 #endif
103
104 static struct mld_ifinfo *
105 mli_alloc_locked(struct ifnet *);
106 static void mli_delete_locked(const struct ifnet *);
107 static void mld_dispatch_packet(struct mbuf *);
108 static void mld_dispatch_queue(struct ifqueue *, int);
109 static void mld_final_leave(struct in6_multi *, struct mld_ifinfo *);
110 static void mld_fasttimo_vnet(void);
111 static int mld_handle_state_change(struct in6_multi *,
112 struct mld_ifinfo *);
113 static int mld_initial_join(struct in6_multi *, struct mld_ifinfo *,
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_ifinfo *, 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 *, const int);
125 static void mld_v1_process_querier_timers(struct mld_ifinfo *);
126 static int mld_v1_transmit_report(struct in6_multi *, const int);
127 static void mld_v1_update_group(struct in6_multi *, const int);
128 static void mld_v2_cancel_link_timers(struct mld_ifinfo *);
129 static void mld_v2_dispatch_general_query(struct mld_ifinfo *);
130 static struct mbuf *
131 mld_v2_encap_report(struct ifnet *, struct mbuf *);
132 static int mld_v2_enqueue_filter_change(struct ifqueue *,
133 struct in6_multi *);
134 static int mld_v2_enqueue_group_record(struct ifqueue *,
135 struct in6_multi *, const int, const int, const int,
136 const int);
137 static int mld_v2_input_query(struct ifnet *, const struct ip6_hdr *,
138 struct mbuf *, const int, const int);
139 static int mld_v2_merge_state_changes(struct in6_multi *,
140 struct ifqueue *);
141 static void mld_v2_process_group_timers(struct mld_ifinfo *,
142 struct ifqueue *, struct ifqueue *,
143 struct in6_multi *, const int);
144 static int mld_v2_process_group_query(struct in6_multi *,
145 struct mld_ifinfo *mli, int, struct mbuf *, const int);
146 static int sysctl_mld_gsr(SYSCTL_HANDLER_ARGS);
147 static int sysctl_mld_ifinfo(SYSCTL_HANDLER_ARGS);
148
149 /*
150 * Normative references: RFC 2710, RFC 3590, RFC 3810.
151 *
152 * Locking:
153 * * The MLD subsystem lock ends up being system-wide for the moment,
154 * but could be per-VIMAGE later on.
155 * * The permitted lock order is: IN6_MULTI_LOCK, MLD_LOCK, IF_ADDR_LOCK.
156 * Any may be taken independently; if any are held at the same
157 * time, the above lock order must be followed.
158 * * IN6_MULTI_LOCK covers in_multi.
159 * * MLD_LOCK covers per-link state and any global variables in this file.
160 * * IF_ADDR_LOCK covers if_multiaddrs, which is used for a variety of
161 * per-link state iterators.
162 *
163 * XXX LOR PREVENTION
164 * A special case for IPv6 is the in6_setscope() routine. ip6_output()
165 * will not accept an ifp; it wants an embedded scope ID, unlike
166 * ip_output(), which happily takes the ifp given to it. The embedded
167 * scope ID is only used by MLD to select the outgoing interface.
168 *
169 * During interface attach and detach, MLD will take MLD_LOCK *after*
170 * the IF_AFDATA_LOCK.
171 * As in6_setscope() takes IF_AFDATA_LOCK then SCOPE_LOCK, we can't call
172 * it with MLD_LOCK held without triggering an LOR. A netisr with indirect
173 * dispatch could work around this, but we'd rather not do that, as it
174 * can introduce other races.
175 *
176 * As such, we exploit the fact that the scope ID is just the interface
177 * index, and embed it in the IPv6 destination address accordingly.
178 * This is potentially NOT VALID for MLDv1 reports, as they
179 * are always sent to the multicast group itself; as MLDv2
180 * reports are always sent to ff02::16, this is not an issue
181 * when MLDv2 is in use.
182 *
183 * This does not however eliminate the LOR when ip6_output() itself
184 * calls in6_setscope() internally whilst MLD_LOCK is held. This will
185 * trigger a LOR warning in WITNESS when the ifnet is detached.
186 *
187 * The right answer is probably to make IF_AFDATA_LOCK an rwlock, given
188 * how it's used across the network stack. Here we're simply exploiting
189 * the fact that MLD runs at a similar layer in the stack to scope6.c.
190 *
191 * VIMAGE:
192 * * Each in6_multi corresponds to an ifp, and each ifp corresponds
193 * to a vnet in ifp->if_vnet.
194 */
195 static struct mtx mld_mtx;
196 MALLOC_DEFINE(M_MLD, "mld", "mld state");
197
198 #define MLD_EMBEDSCOPE(pin6, zoneid) \
199 if (IN6_IS_SCOPE_LINKLOCAL(pin6) || \
200 IN6_IS_ADDR_MC_INTFACELOCAL(pin6)) \
201 (pin6)->s6_addr16[1] = htons((zoneid) & 0xFFFF) \
202
203 /*
204 * VIMAGE-wide globals.
205 */
206 static VNET_DEFINE(struct timeval, mld_gsrdelay) = {10, 0};
207 static VNET_DEFINE(LIST_HEAD(, mld_ifinfo), mli_head);
208 static VNET_DEFINE(int, interface_timers_running6);
209 static VNET_DEFINE(int, state_change_timers_running6);
210 static VNET_DEFINE(int, current_state_timers_running6);
211
212 #define V_mld_gsrdelay VNET(mld_gsrdelay)
213 #define V_mli_head VNET(mli_head)
214 #define V_interface_timers_running6 VNET(interface_timers_running6)
215 #define V_state_change_timers_running6 VNET(state_change_timers_running6)
216 #define V_current_state_timers_running6 VNET(current_state_timers_running6)
217
218 SYSCTL_DECL(_net_inet6); /* Note: Not in any common header. */
219
220 SYSCTL_NODE(_net_inet6, OID_AUTO, mld, CTLFLAG_RW, 0,
221 "IPv6 Multicast Listener Discovery");
222
223 /*
224 * Virtualized sysctls.
225 */
226 SYSCTL_VNET_PROC(_net_inet6_mld, OID_AUTO, gsrdelay,
227 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
228 &VNET_NAME(mld_gsrdelay.tv_sec), 0, sysctl_mld_gsr, "I",
229 "Rate limit for MLDv2 Group-and-Source queries in seconds");
230
231 /*
232 * Non-virtualized sysctls.
233 */
234 SYSCTL_NODE(_net_inet6_mld, OID_AUTO, ifinfo, CTLFLAG_RD | CTLFLAG_MPSAFE,
235 sysctl_mld_ifinfo, "Per-interface MLDv2 state");
236
237 static int mld_v1enable = 1;
238 SYSCTL_INT(_net_inet6_mld, OID_AUTO, v1enable, CTLFLAG_RW,
239 &mld_v1enable, 0, "Enable fallback to MLDv1");
240 TUNABLE_INT("net.inet6.mld.v1enable", &mld_v1enable);
241
242 static int mld_use_allow = 1;
243 SYSCTL_INT(_net_inet6_mld, OID_AUTO, use_allow, CTLFLAG_RW,
244 &mld_use_allow, 0, "Use ALLOW/BLOCK for RFC 4604 SSM joins/leaves");
245 TUNABLE_INT("net.inet6.mld.use_allow", &mld_use_allow);
246
247 /*
248 * Packed Router Alert option structure declaration.
249 */
250 struct mld_raopt {
251 struct ip6_hbh hbh;
252 struct ip6_opt pad;
253 struct ip6_opt_router ra;
254 } __packed;
255
256 /*
257 * Router Alert hop-by-hop option header.
258 */
259 static struct mld_raopt mld_ra = {
260 .hbh = { 0, 0 },
261 .pad = { .ip6o_type = IP6OPT_PADN, 0 },
262 .ra = {
263 .ip6or_type = IP6OPT_ROUTER_ALERT,
264 .ip6or_len = IP6OPT_RTALERT_LEN - 2,
265 .ip6or_value[0] = ((IP6OPT_RTALERT_MLD >> 8) & 0xFF),
266 .ip6or_value[1] = (IP6OPT_RTALERT_MLD & 0xFF)
267 }
268 };
269 static struct ip6_pktopts mld_po;
270
271 static __inline void
272 mld_save_context(struct mbuf *m, struct ifnet *ifp)
273 {
274
275 #ifdef VIMAGE
276 m->m_pkthdr.header = ifp->if_vnet;
277 #endif /* VIMAGE */
278 m->m_pkthdr.flowid = ifp->if_index;
279 }
280
281 static __inline void
282 mld_scrub_context(struct mbuf *m)
283 {
284
285 m->m_pkthdr.header = NULL;
286 m->m_pkthdr.flowid = 0;
287 }
288
289 /*
290 * Restore context from a queued output chain.
291 * Return saved ifindex.
292 *
293 * VIMAGE: The assertion is there to make sure that we
294 * actually called CURVNET_SET() with what's in the mbuf chain.
295 */
296 static __inline uint32_t
297 mld_restore_context(struct mbuf *m)
298 {
299
300 #if defined(VIMAGE) && defined(INVARIANTS)
301 KASSERT(curvnet == m->m_pkthdr.header,
302 ("%s: called when curvnet was not restored", __func__));
303 #endif
304 return (m->m_pkthdr.flowid);
305 }
306
307 /*
308 * Retrieve or set threshold between group-source queries in seconds.
309 *
310 * VIMAGE: Assume curvnet set by caller.
311 * SMPng: NOTE: Serialized by MLD lock.
312 */
313 static int
314 sysctl_mld_gsr(SYSCTL_HANDLER_ARGS)
315 {
316 int error;
317 int i;
318
319 error = sysctl_wire_old_buffer(req, sizeof(int));
320 if (error)
321 return (error);
322
323 MLD_LOCK();
324
325 i = V_mld_gsrdelay.tv_sec;
326
327 error = sysctl_handle_int(oidp, &i, 0, req);
328 if (error || !req->newptr)
329 goto out_locked;
330
331 if (i < -1 || i >= 60) {
332 error = EINVAL;
333 goto out_locked;
334 }
335
336 CTR2(KTR_MLD, "change mld_gsrdelay from %d to %d",
337 V_mld_gsrdelay.tv_sec, i);
338 V_mld_gsrdelay.tv_sec = i;
339
340 out_locked:
341 MLD_UNLOCK();
342 return (error);
343 }
344
345 /*
346 * Expose struct mld_ifinfo to userland, keyed by ifindex.
347 * For use by ifmcstat(8).
348 *
349 * SMPng: NOTE: Does an unlocked ifindex space read.
350 * VIMAGE: Assume curvnet set by caller. The node handler itself
351 * is not directly virtualized.
352 */
353 static int
354 sysctl_mld_ifinfo(SYSCTL_HANDLER_ARGS)
355 {
356 int *name;
357 int error;
358 u_int namelen;
359 struct ifnet *ifp;
360 struct mld_ifinfo *mli;
361
362 name = (int *)arg1;
363 namelen = arg2;
364
365 if (req->newptr != NULL)
366 return (EPERM);
367
368 if (namelen != 1)
369 return (EINVAL);
370
371 error = sysctl_wire_old_buffer(req, sizeof(struct mld_ifinfo));
372 if (error)
373 return (error);
374
375 IN6_MULTI_LOCK();
376 MLD_LOCK();
377
378 if (name[0] <= 0 || name[0] > V_if_index) {
379 error = ENOENT;
380 goto out_locked;
381 }
382
383 error = ENOENT;
384
385 ifp = ifnet_byindex(name[0]);
386 if (ifp == NULL)
387 goto out_locked;
388
389 LIST_FOREACH(mli, &V_mli_head, mli_link) {
390 if (ifp == mli->mli_ifp) {
391 error = SYSCTL_OUT(req, mli,
392 sizeof(struct mld_ifinfo));
393 break;
394 }
395 }
396
397 out_locked:
398 MLD_UNLOCK();
399 IN6_MULTI_UNLOCK();
400 return (error);
401 }
402
403 /*
404 * Dispatch an entire queue of pending packet chains.
405 * VIMAGE: Assumes the vnet pointer has been set.
406 */
407 static void
408 mld_dispatch_queue(struct ifqueue *ifq, int limit)
409 {
410 struct mbuf *m;
411
412 for (;;) {
413 _IF_DEQUEUE(ifq, m);
414 if (m == NULL)
415 break;
416 CTR3(KTR_MLD, "%s: dispatch %p from %p", __func__, ifq, m);
417 mld_dispatch_packet(m);
418 if (--limit == 0)
419 break;
420 }
421 }
422
423 /*
424 * Filter outgoing MLD report state by group.
425 *
426 * Reports are ALWAYS suppressed for ALL-HOSTS (ff02::1)
427 * and node-local addresses. However, kernel and socket consumers
428 * always embed the KAME scope ID in the address provided, so strip it
429 * when performing comparison.
430 * Note: This is not the same as the *multicast* scope.
431 *
432 * Return zero if the given group is one for which MLD reports
433 * should be suppressed, or non-zero if reports should be issued.
434 */
435 static __inline int
436 mld_is_addr_reported(const struct in6_addr *addr)
437 {
438
439 KASSERT(IN6_IS_ADDR_MULTICAST(addr), ("%s: not multicast", __func__));
440
441 if (IPV6_ADDR_MC_SCOPE(addr) == IPV6_ADDR_SCOPE_NODELOCAL)
442 return (0);
443
444 if (IPV6_ADDR_MC_SCOPE(addr) == IPV6_ADDR_SCOPE_LINKLOCAL) {
445 struct in6_addr tmp = *addr;
446 in6_clearscope(&tmp);
447 if (IN6_ARE_ADDR_EQUAL(&tmp, &in6addr_linklocal_allnodes))
448 return (0);
449 }
450
451 return (1);
452 }
453
454 /*
455 * Attach MLD when PF_INET6 is attached to an interface.
456 *
457 * SMPng: Normally called with IF_AFDATA_LOCK held.
458 */
459 struct mld_ifinfo *
460 mld_domifattach(struct ifnet *ifp)
461 {
462 struct mld_ifinfo *mli;
463
464 CTR3(KTR_MLD, "%s: called for ifp %p(%s)",
465 __func__, ifp, ifp->if_xname);
466
467 MLD_LOCK();
468
469 mli = mli_alloc_locked(ifp);
470 if (!(ifp->if_flags & IFF_MULTICAST))
471 mli->mli_flags |= MLIF_SILENT;
472 if (mld_use_allow)
473 mli->mli_flags |= MLIF_USEALLOW;
474
475 MLD_UNLOCK();
476
477 return (mli);
478 }
479
480 /*
481 * VIMAGE: assume curvnet set by caller.
482 */
483 static struct mld_ifinfo *
484 mli_alloc_locked(/*const*/ struct ifnet *ifp)
485 {
486 struct mld_ifinfo *mli;
487
488 MLD_LOCK_ASSERT();
489
490 mli = malloc(sizeof(struct mld_ifinfo), M_MLD, M_NOWAIT|M_ZERO);
491 if (mli == NULL)
492 goto out;
493
494 mli->mli_ifp = ifp;
495 mli->mli_version = MLD_VERSION_2;
496 mli->mli_flags = 0;
497 mli->mli_rv = MLD_RV_INIT;
498 mli->mli_qi = MLD_QI_INIT;
499 mli->mli_qri = MLD_QRI_INIT;
500 mli->mli_uri = MLD_URI_INIT;
501
502 SLIST_INIT(&mli->mli_relinmhead);
503
504 /*
505 * Responses to general queries are subject to bounds.
506 */
507 IFQ_SET_MAXLEN(&mli->mli_gq, MLD_MAX_RESPONSE_PACKETS);
508
509 LIST_INSERT_HEAD(&V_mli_head, mli, mli_link);
510
511 CTR2(KTR_MLD, "allocate mld_ifinfo for ifp %p(%s)",
512 ifp, ifp->if_xname);
513
514 out:
515 return (mli);
516 }
517
518 /*
519 * Hook for ifdetach.
520 *
521 * NOTE: Some finalization tasks need to run before the protocol domain
522 * is detached, but also before the link layer does its cleanup.
523 * Run before link-layer cleanup; cleanup groups, but do not free MLD state.
524 *
525 * SMPng: Caller must hold IN6_MULTI_LOCK().
526 * Must take IF_ADDR_LOCK() to cover if_multiaddrs iterator.
527 * XXX This routine is also bitten by unlocked ifma_protospec access.
528 */
529 void
530 mld_ifdetach(struct ifnet *ifp)
531 {
532 struct mld_ifinfo *mli;
533 struct ifmultiaddr *ifma;
534 struct in6_multi *inm, *tinm;
535
536 CTR3(KTR_MLD, "%s: called for ifp %p(%s)", __func__, ifp,
537 ifp->if_xname);
538
539 IN6_MULTI_LOCK_ASSERT();
540 MLD_LOCK();
541
542 mli = MLD_IFINFO(ifp);
543 if (mli->mli_version == MLD_VERSION_2) {
544 IF_ADDR_LOCK(ifp);
545 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
546 if (ifma->ifma_addr->sa_family != AF_INET6 ||
547 ifma->ifma_protospec == NULL)
548 continue;
549 inm = (struct in6_multi *)ifma->ifma_protospec;
550 if (inm->in6m_state == MLD_LEAVING_MEMBER) {
551 SLIST_INSERT_HEAD(&mli->mli_relinmhead,
552 inm, in6m_nrele);
553 }
554 in6m_clear_recorded(inm);
555 }
556 IF_ADDR_UNLOCK(ifp);
557 SLIST_FOREACH_SAFE(inm, &mli->mli_relinmhead, in6m_nrele,
558 tinm) {
559 SLIST_REMOVE_HEAD(&mli->mli_relinmhead, in6m_nrele);
560 in6m_release_locked(inm);
561 }
562 }
563
564 MLD_UNLOCK();
565 }
566
567 /*
568 * Hook for domifdetach.
569 * Runs after link-layer cleanup; free MLD state.
570 *
571 * SMPng: Normally called with IF_AFDATA_LOCK held.
572 */
573 void
574 mld_domifdetach(struct ifnet *ifp)
575 {
576
577 CTR3(KTR_MLD, "%s: called for ifp %p(%s)",
578 __func__, ifp, ifp->if_xname);
579
580 MLD_LOCK();
581 mli_delete_locked(ifp);
582 MLD_UNLOCK();
583 }
584
585 static void
586 mli_delete_locked(const struct ifnet *ifp)
587 {
588 struct mld_ifinfo *mli, *tmli;
589
590 CTR3(KTR_MLD, "%s: freeing mld_ifinfo for ifp %p(%s)",
591 __func__, ifp, ifp->if_xname);
592
593 MLD_LOCK_ASSERT();
594
595 LIST_FOREACH_SAFE(mli, &V_mli_head, mli_link, tmli) {
596 if (mli->mli_ifp == ifp) {
597 /*
598 * Free deferred General Query responses.
599 */
600 _IF_DRAIN(&mli->mli_gq);
601
602 LIST_REMOVE(mli, mli_link);
603
604 KASSERT(SLIST_EMPTY(&mli->mli_relinmhead),
605 ("%s: there are dangling in_multi references",
606 __func__));
607
608 free(mli, M_MLD);
609 return;
610 }
611 }
612 #ifdef INVARIANTS
613 panic("%s: mld_ifinfo not found for ifp %p\n", __func__, ifp);
614 #endif
615 }
616
617 /*
618 * Process a received MLDv1 general or address-specific query.
619 * Assumes that the query header has been pulled up to sizeof(mld_hdr).
620 *
621 * NOTE: Can't be fully const correct as we temporarily embed scope ID in
622 * mld_addr. This is OK as we own the mbuf chain.
623 */
624 static int
625 mld_v1_input_query(struct ifnet *ifp, const struct ip6_hdr *ip6,
626 /*const*/ struct mld_hdr *mld)
627 {
628 struct ifmultiaddr *ifma;
629 struct mld_ifinfo *mli;
630 struct in6_multi *inm;
631 int is_general_query;
632 uint16_t timer;
633 #ifdef KTR
634 char ip6tbuf[INET6_ADDRSTRLEN];
635 #endif
636
637 is_general_query = 0;
638
639 if (!mld_v1enable) {
640 CTR3(KTR_MLD, "ignore v1 query %s on ifp %p(%s)",
641 ip6_sprintf(ip6tbuf, &mld->mld_addr),
642 ifp, ifp->if_xname);
643 return (0);
644 }
645
646 /*
647 * RFC3810 Section 6.2: MLD queries must originate from
648 * a router's link-local address.
649 */
650 if (!IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
651 CTR3(KTR_MLD, "ignore v1 query src %s on ifp %p(%s)",
652 ip6_sprintf(ip6tbuf, &ip6->ip6_src),
653 ifp, ifp->if_xname);
654 return (0);
655 }
656
657 /*
658 * Do address field validation upfront before we accept
659 * the query.
660 */
661 if (IN6_IS_ADDR_UNSPECIFIED(&mld->mld_addr)) {
662 /*
663 * MLDv1 General Query.
664 * If this was not sent to the all-nodes group, ignore it.
665 */
666 struct in6_addr dst;
667
668 dst = ip6->ip6_dst;
669 in6_clearscope(&dst);
670 if (!IN6_ARE_ADDR_EQUAL(&dst, &in6addr_linklocal_allnodes))
671 return (EINVAL);
672 is_general_query = 1;
673 } else {
674 /*
675 * Embed scope ID of receiving interface in MLD query for
676 * lookup whilst we don't hold other locks.
677 */
678 in6_setscope(&mld->mld_addr, ifp, NULL);
679 }
680
681 IN6_MULTI_LOCK();
682 MLD_LOCK();
683
684 /*
685 * Switch to MLDv1 host compatibility mode.
686 */
687 mli = MLD_IFINFO(ifp);
688 KASSERT(mli != NULL, ("%s: no mld_ifinfo for ifp %p", __func__, ifp));
689 mld_set_version(mli, MLD_VERSION_1);
690
691 timer = (ntohs(mld->mld_maxdelay) * PR_FASTHZ) / MLD_TIMER_SCALE;
692 if (timer == 0)
693 timer = 1;
694
695 IF_ADDR_LOCK(ifp);
696 if (is_general_query) {
697 /*
698 * For each reporting group joined on this
699 * interface, kick the report timer.
700 */
701 CTR2(KTR_MLD, "process v1 general query on ifp %p(%s)",
702 ifp, ifp->if_xname);
703 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
704 if (ifma->ifma_addr->sa_family != AF_INET6 ||
705 ifma->ifma_protospec == NULL)
706 continue;
707 inm = (struct in6_multi *)ifma->ifma_protospec;
708 mld_v1_update_group(inm, timer);
709 }
710 } else {
711 /*
712 * MLDv1 Group-Specific Query.
713 * If this is a group-specific MLDv1 query, we need only
714 * look up the single group to process it.
715 */
716 inm = in6m_lookup_locked(ifp, &mld->mld_addr);
717 if (inm != NULL) {
718 CTR3(KTR_MLD, "process v1 query %s on ifp %p(%s)",
719 ip6_sprintf(ip6tbuf, &mld->mld_addr),
720 ifp, ifp->if_xname);
721 mld_v1_update_group(inm, timer);
722 }
723 /* XXX Clear embedded scope ID as userland won't expect it. */
724 in6_clearscope(&mld->mld_addr);
725 }
726
727 IF_ADDR_UNLOCK(ifp);
728 MLD_UNLOCK();
729 IN6_MULTI_UNLOCK();
730
731 return (0);
732 }
733
734 /*
735 * Update the report timer on a group in response to an MLDv1 query.
736 *
737 * If we are becoming the reporting member for this group, start the timer.
738 * If we already are the reporting member for this group, and timer is
739 * below the threshold, reset it.
740 *
741 * We may be updating the group for the first time since we switched
742 * to MLDv2. If we are, then we must clear any recorded source lists,
743 * and transition to REPORTING state; the group timer is overloaded
744 * for group and group-source query responses.
745 *
746 * Unlike MLDv2, the delay per group should be jittered
747 * to avoid bursts of MLDv1 reports.
748 */
749 static void
750 mld_v1_update_group(struct in6_multi *inm, const int timer)
751 {
752 #ifdef KTR
753 char ip6tbuf[INET6_ADDRSTRLEN];
754 #endif
755
756 CTR4(KTR_MLD, "%s: %s/%s timer=%d", __func__,
757 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
758 inm->in6m_ifp->if_xname, timer);
759
760 IN6_MULTI_LOCK_ASSERT();
761
762 switch (inm->in6m_state) {
763 case MLD_NOT_MEMBER:
764 case MLD_SILENT_MEMBER:
765 break;
766 case MLD_REPORTING_MEMBER:
767 if (inm->in6m_timer != 0 &&
768 inm->in6m_timer <= timer) {
769 CTR1(KTR_MLD, "%s: REPORTING and timer running, "
770 "skipping.", __func__);
771 break;
772 }
773 /* FALLTHROUGH */
774 case MLD_SG_QUERY_PENDING_MEMBER:
775 case MLD_G_QUERY_PENDING_MEMBER:
776 case MLD_IDLE_MEMBER:
777 case MLD_LAZY_MEMBER:
778 case MLD_AWAKENING_MEMBER:
779 CTR1(KTR_MLD, "%s: ->REPORTING", __func__);
780 inm->in6m_state = MLD_REPORTING_MEMBER;
781 inm->in6m_timer = MLD_RANDOM_DELAY(timer);
782 V_current_state_timers_running6 = 1;
783 break;
784 case MLD_SLEEPING_MEMBER:
785 CTR1(KTR_MLD, "%s: ->AWAKENING", __func__);
786 inm->in6m_state = MLD_AWAKENING_MEMBER;
787 break;
788 case MLD_LEAVING_MEMBER:
789 break;
790 }
791 }
792
793 /*
794 * Process a received MLDv2 general, group-specific or
795 * group-and-source-specific query.
796 *
797 * Assumes that the query header has been pulled up to sizeof(mldv2_query).
798 *
799 * Return 0 if successful, otherwise an appropriate error code is returned.
800 */
801 static int
802 mld_v2_input_query(struct ifnet *ifp, const struct ip6_hdr *ip6,
803 struct mbuf *m, const int off, const int icmp6len)
804 {
805 struct mld_ifinfo *mli;
806 struct mldv2_query *mld;
807 struct in6_multi *inm;
808 uint32_t maxdelay, nsrc, qqi;
809 int is_general_query;
810 uint16_t timer;
811 uint8_t qrv;
812 #ifdef KTR
813 char ip6tbuf[INET6_ADDRSTRLEN];
814 #endif
815
816 is_general_query = 0;
817
818 /*
819 * RFC3810 Section 6.2: MLD queries must originate from
820 * a router's link-local address.
821 */
822 if (!IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
823 CTR3(KTR_MLD, "ignore v1 query src %s on ifp %p(%s)",
824 ip6_sprintf(ip6tbuf, &ip6->ip6_src),
825 ifp, ifp->if_xname);
826 return (0);
827 }
828
829 CTR2(KTR_MLD, "input v2 query on ifp %p(%s)", ifp, ifp->if_xname);
830
831 mld = (struct mldv2_query *)(mtod(m, uint8_t *) + off);
832
833 maxdelay = ntohs(mld->mld_maxdelay); /* in 1/10ths of a second */
834 if (maxdelay >= 32678) {
835 maxdelay = (MLD_MRC_MANT(maxdelay) | 0x1000) <<
836 (MLD_MRC_EXP(maxdelay) + 3);
837 }
838 timer = (maxdelay * PR_FASTHZ) / MLD_TIMER_SCALE;
839 if (timer == 0)
840 timer = 1;
841
842 qrv = MLD_QRV(mld->mld_misc);
843 if (qrv < 2) {
844 CTR3(KTR_MLD, "%s: clamping qrv %d to %d", __func__,
845 qrv, MLD_RV_INIT);
846 qrv = MLD_RV_INIT;
847 }
848
849 qqi = mld->mld_qqi;
850 if (qqi >= 128) {
851 qqi = MLD_QQIC_MANT(mld->mld_qqi) <<
852 (MLD_QQIC_EXP(mld->mld_qqi) + 3);
853 }
854
855 nsrc = ntohs(mld->mld_numsrc);
856 if (nsrc > MLD_MAX_GS_SOURCES)
857 return (EMSGSIZE);
858 if (icmp6len < sizeof(struct mldv2_query) +
859 (nsrc * sizeof(struct in6_addr)))
860 return (EMSGSIZE);
861
862 /*
863 * Do further input validation upfront to avoid resetting timers
864 * should we need to discard this query.
865 */
866 if (IN6_IS_ADDR_UNSPECIFIED(&mld->mld_addr)) {
867 /*
868 * General Queries SHOULD be directed to ff02::1.
869 * A general query with a source list has undefined
870 * behaviour; discard it.
871 */
872 struct in6_addr dst;
873
874 dst = ip6->ip6_dst;
875 in6_clearscope(&dst);
876 if (!IN6_ARE_ADDR_EQUAL(&dst, &in6addr_linklocal_allnodes) ||
877 nsrc > 0)
878 return (EINVAL);
879 is_general_query = 1;
880 } else {
881 /*
882 * Embed scope ID of receiving interface in MLD query for
883 * lookup whilst we don't hold other locks (due to KAME
884 * locking lameness). We own this mbuf chain just now.
885 */
886 in6_setscope(&mld->mld_addr, ifp, NULL);
887 }
888
889 IN6_MULTI_LOCK();
890 MLD_LOCK();
891
892 mli = MLD_IFINFO(ifp);
893 KASSERT(mli != NULL, ("%s: no mld_ifinfo for ifp %p", __func__, ifp));
894
895 /*
896 * Discard the v2 query if we're in Compatibility Mode.
897 * The RFC is pretty clear that hosts need to stay in MLDv1 mode
898 * until the Old Version Querier Present timer expires.
899 */
900 if (mli->mli_version != MLD_VERSION_2)
901 goto out_locked;
902
903 mld_set_version(mli, MLD_VERSION_2);
904 mli->mli_rv = qrv;
905 mli->mli_qi = qqi;
906 mli->mli_qri = maxdelay;
907
908 CTR4(KTR_MLD, "%s: qrv %d qi %d maxdelay %d", __func__, qrv, qqi,
909 maxdelay);
910
911 if (is_general_query) {
912 /*
913 * MLDv2 General Query.
914 *
915 * Schedule a current-state report on this ifp for
916 * all groups, possibly containing source lists.
917 *
918 * If there is a pending General Query response
919 * scheduled earlier than the selected delay, do
920 * not schedule any other reports.
921 * Otherwise, reset the interface timer.
922 */
923 CTR2(KTR_MLD, "process v2 general query on ifp %p(%s)",
924 ifp, ifp->if_xname);
925 if (mli->mli_v2_timer == 0 || mli->mli_v2_timer >= timer) {
926 mli->mli_v2_timer = MLD_RANDOM_DELAY(timer);
927 V_interface_timers_running6 = 1;
928 }
929 } else {
930 /*
931 * MLDv2 Group-specific or Group-and-source-specific Query.
932 *
933 * Group-source-specific queries are throttled on
934 * a per-group basis to defeat denial-of-service attempts.
935 * Queries for groups we are not a member of on this
936 * link are simply ignored.
937 */
938 IF_ADDR_LOCK(ifp);
939 inm = in6m_lookup_locked(ifp, &mld->mld_addr);
940 if (inm == NULL) {
941 IF_ADDR_UNLOCK(ifp);
942 goto out_locked;
943 }
944 if (nsrc > 0) {
945 if (!ratecheck(&inm->in6m_lastgsrtv,
946 &V_mld_gsrdelay)) {
947 CTR1(KTR_MLD, "%s: GS query throttled.",
948 __func__);
949 IF_ADDR_UNLOCK(ifp);
950 goto out_locked;
951 }
952 }
953 CTR2(KTR_MLD, "process v2 group query on ifp %p(%s)",
954 ifp, ifp->if_xname);
955 /*
956 * If there is a pending General Query response
957 * scheduled sooner than the selected delay, no
958 * further report need be scheduled.
959 * Otherwise, prepare to respond to the
960 * group-specific or group-and-source query.
961 */
962 if (mli->mli_v2_timer == 0 || mli->mli_v2_timer >= timer)
963 mld_v2_process_group_query(inm, mli, timer, m, off);
964
965 /* XXX Clear embedded scope ID as userland won't expect it. */
966 in6_clearscope(&mld->mld_addr);
967 IF_ADDR_UNLOCK(ifp);
968 }
969
970 out_locked:
971 MLD_UNLOCK();
972 IN6_MULTI_UNLOCK();
973
974 return (0);
975 }
976
977 /*
978 * Process a recieved MLDv2 group-specific or group-and-source-specific
979 * query.
980 * Return <0 if any error occured. Currently this is ignored.
981 */
982 static int
983 mld_v2_process_group_query(struct in6_multi *inm, struct mld_ifinfo *mli,
984 int timer, struct mbuf *m0, const int off)
985 {
986 struct mldv2_query *mld;
987 int retval;
988 uint16_t nsrc;
989
990 IN6_MULTI_LOCK_ASSERT();
991 MLD_LOCK_ASSERT();
992
993 retval = 0;
994 mld = (struct mldv2_query *)(mtod(m0, uint8_t *) + off);
995
996 switch (inm->in6m_state) {
997 case MLD_NOT_MEMBER:
998 case MLD_SILENT_MEMBER:
999 case MLD_SLEEPING_MEMBER:
1000 case MLD_LAZY_MEMBER:
1001 case MLD_AWAKENING_MEMBER:
1002 case MLD_IDLE_MEMBER:
1003 case MLD_LEAVING_MEMBER:
1004 return (retval);
1005 break;
1006 case MLD_REPORTING_MEMBER:
1007 case MLD_G_QUERY_PENDING_MEMBER:
1008 case MLD_SG_QUERY_PENDING_MEMBER:
1009 break;
1010 }
1011
1012 nsrc = ntohs(mld->mld_numsrc);
1013
1014 /*
1015 * Deal with group-specific queries upfront.
1016 * If any group query is already pending, purge any recorded
1017 * source-list state if it exists, and schedule a query response
1018 * for this group-specific query.
1019 */
1020 if (nsrc == 0) {
1021 if (inm->in6m_state == MLD_G_QUERY_PENDING_MEMBER ||
1022 inm->in6m_state == MLD_SG_QUERY_PENDING_MEMBER) {
1023 in6m_clear_recorded(inm);
1024 timer = min(inm->in6m_timer, timer);
1025 }
1026 inm->in6m_state = MLD_G_QUERY_PENDING_MEMBER;
1027 inm->in6m_timer = MLD_RANDOM_DELAY(timer);
1028 V_current_state_timers_running6 = 1;
1029 return (retval);
1030 }
1031
1032 /*
1033 * Deal with the case where a group-and-source-specific query has
1034 * been received but a group-specific query is already pending.
1035 */
1036 if (inm->in6m_state == MLD_G_QUERY_PENDING_MEMBER) {
1037 timer = min(inm->in6m_timer, timer);
1038 inm->in6m_timer = MLD_RANDOM_DELAY(timer);
1039 V_current_state_timers_running6 = 1;
1040 return (retval);
1041 }
1042
1043 /*
1044 * Finally, deal with the case where a group-and-source-specific
1045 * query has been received, where a response to a previous g-s-r
1046 * query exists, or none exists.
1047 * In this case, we need to parse the source-list which the Querier
1048 * has provided us with and check if we have any source list filter
1049 * entries at T1 for these sources. If we do not, there is no need
1050 * schedule a report and the query may be dropped.
1051 * If we do, we must record them and schedule a current-state
1052 * report for those sources.
1053 */
1054 if (inm->in6m_nsrc > 0) {
1055 struct mbuf *m;
1056 uint8_t *sp;
1057 int i, nrecorded;
1058 int soff;
1059
1060 m = m0;
1061 soff = off + sizeof(struct mldv2_query);
1062 nrecorded = 0;
1063 for (i = 0; i < nsrc; i++) {
1064 sp = mtod(m, uint8_t *) + soff;
1065 retval = in6m_record_source(inm,
1066 (const struct in6_addr *)sp);
1067 if (retval < 0)
1068 break;
1069 nrecorded += retval;
1070 soff += sizeof(struct in6_addr);
1071 if (soff >= m->m_len) {
1072 soff = soff - m->m_len;
1073 m = m->m_next;
1074 if (m == NULL)
1075 break;
1076 }
1077 }
1078 if (nrecorded > 0) {
1079 CTR1(KTR_MLD,
1080 "%s: schedule response to SG query", __func__);
1081 inm->in6m_state = MLD_SG_QUERY_PENDING_MEMBER;
1082 inm->in6m_timer = MLD_RANDOM_DELAY(timer);
1083 V_current_state_timers_running6 = 1;
1084 }
1085 }
1086
1087 return (retval);
1088 }
1089
1090 /*
1091 * Process a received MLDv1 host membership report.
1092 * Assumes mld points to mld_hdr in pulled up mbuf chain.
1093 *
1094 * NOTE: Can't be fully const correct as we temporarily embed scope ID in
1095 * mld_addr. This is OK as we own the mbuf chain.
1096 */
1097 static int
1098 mld_v1_input_report(struct ifnet *ifp, const struct ip6_hdr *ip6,
1099 /*const*/ struct mld_hdr *mld)
1100 {
1101 struct in6_addr src, dst;
1102 struct in6_ifaddr *ia;
1103 struct in6_multi *inm;
1104 #ifdef KTR
1105 char ip6tbuf[INET6_ADDRSTRLEN];
1106 #endif
1107
1108 if (!mld_v1enable) {
1109 CTR3(KTR_MLD, "ignore v1 report %s on ifp %p(%s)",
1110 ip6_sprintf(ip6tbuf, &mld->mld_addr),
1111 ifp, ifp->if_xname);
1112 return (0);
1113 }
1114
1115 if (ifp->if_flags & IFF_LOOPBACK)
1116 return (0);
1117
1118 /*
1119 * MLDv1 reports must originate from a host's link-local address,
1120 * or the unspecified address (when booting).
1121 */
1122 src = ip6->ip6_src;
1123 in6_clearscope(&src);
1124 if (!IN6_IS_SCOPE_LINKLOCAL(&src) && !IN6_IS_ADDR_UNSPECIFIED(&src)) {
1125 CTR3(KTR_MLD, "ignore v1 query src %s on ifp %p(%s)",
1126 ip6_sprintf(ip6tbuf, &ip6->ip6_src),
1127 ifp, ifp->if_xname);
1128 return (EINVAL);
1129 }
1130
1131 /*
1132 * RFC2710 Section 4: MLDv1 reports must pertain to a multicast
1133 * group, and must be directed to the group itself.
1134 */
1135 dst = ip6->ip6_dst;
1136 in6_clearscope(&dst);
1137 if (!IN6_IS_ADDR_MULTICAST(&mld->mld_addr) ||
1138 !IN6_ARE_ADDR_EQUAL(&mld->mld_addr, &dst)) {
1139 CTR3(KTR_MLD, "ignore v1 query dst %s on ifp %p(%s)",
1140 ip6_sprintf(ip6tbuf, &ip6->ip6_dst),
1141 ifp, ifp->if_xname);
1142 return (EINVAL);
1143 }
1144
1145 /*
1146 * Make sure we don't hear our own membership report, as fast
1147 * leave requires knowing that we are the only member of a
1148 * group. Assume we used the link-local address if available,
1149 * otherwise look for ::.
1150 *
1151 * XXX Note that scope ID comparison is needed for the address
1152 * returned by in6ifa_ifpforlinklocal(), but SHOULD NOT be
1153 * performed for the on-wire address.
1154 */
1155 ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
1156 if ((ia && IN6_ARE_ADDR_EQUAL(&ip6->ip6_src, IA6_IN6(ia))) ||
1157 (ia == NULL && IN6_IS_ADDR_UNSPECIFIED(&src))) {
1158 if (ia != NULL)
1159 ifa_free(&ia->ia_ifa);
1160 return (0);
1161 }
1162 if (ia != NULL)
1163 ifa_free(&ia->ia_ifa);
1164
1165 CTR3(KTR_MLD, "process v1 report %s on ifp %p(%s)",
1166 ip6_sprintf(ip6tbuf, &mld->mld_addr), ifp, ifp->if_xname);
1167
1168 /*
1169 * Embed scope ID of receiving interface in MLD query for lookup
1170 * whilst we don't hold other locks (due to KAME locking lameness).
1171 */
1172 if (!IN6_IS_ADDR_UNSPECIFIED(&mld->mld_addr))
1173 in6_setscope(&mld->mld_addr, ifp, NULL);
1174
1175 IN6_MULTI_LOCK();
1176 MLD_LOCK();
1177 IF_ADDR_LOCK(ifp);
1178
1179 /*
1180 * MLDv1 report suppression.
1181 * If we are a member of this group, and our membership should be
1182 * reported, and our group timer is pending or about to be reset,
1183 * stop our group timer by transitioning to the 'lazy' state.
1184 */
1185 inm = in6m_lookup_locked(ifp, &mld->mld_addr);
1186 if (inm != NULL) {
1187 struct mld_ifinfo *mli;
1188
1189 mli = inm->in6m_mli;
1190 KASSERT(mli != NULL,
1191 ("%s: no mli for ifp %p", __func__, ifp));
1192
1193 /*
1194 * If we are in MLDv2 host mode, do not allow the
1195 * other host's MLDv1 report to suppress our reports.
1196 */
1197 if (mli->mli_version == MLD_VERSION_2)
1198 goto out_locked;
1199
1200 inm->in6m_timer = 0;
1201
1202 switch (inm->in6m_state) {
1203 case MLD_NOT_MEMBER:
1204 case MLD_SILENT_MEMBER:
1205 case MLD_SLEEPING_MEMBER:
1206 break;
1207 case MLD_REPORTING_MEMBER:
1208 case MLD_IDLE_MEMBER:
1209 case MLD_AWAKENING_MEMBER:
1210 CTR3(KTR_MLD,
1211 "report suppressed for %s on ifp %p(%s)",
1212 ip6_sprintf(ip6tbuf, &mld->mld_addr),
1213 ifp, ifp->if_xname);
1214 case MLD_LAZY_MEMBER:
1215 inm->in6m_state = MLD_LAZY_MEMBER;
1216 break;
1217 case MLD_G_QUERY_PENDING_MEMBER:
1218 case MLD_SG_QUERY_PENDING_MEMBER:
1219 case MLD_LEAVING_MEMBER:
1220 break;
1221 }
1222 }
1223
1224 out_locked:
1225 MLD_UNLOCK();
1226 IF_ADDR_UNLOCK(ifp);
1227 IN6_MULTI_UNLOCK();
1228
1229 /* XXX Clear embedded scope ID as userland won't expect it. */
1230 in6_clearscope(&mld->mld_addr);
1231
1232 return (0);
1233 }
1234
1235 /*
1236 * MLD input path.
1237 *
1238 * Assume query messages which fit in a single ICMPv6 message header
1239 * have been pulled up.
1240 * Assume that userland will want to see the message, even if it
1241 * otherwise fails kernel input validation; do not free it.
1242 * Pullup may however free the mbuf chain m if it fails.
1243 *
1244 * Return IPPROTO_DONE if we freed m. Otherwise, return 0.
1245 */
1246 int
1247 mld_input(struct mbuf *m, int off, int icmp6len)
1248 {
1249 struct ifnet *ifp;
1250 struct ip6_hdr *ip6;
1251 struct mld_hdr *mld;
1252 int mldlen;
1253
1254 CTR3(KTR_MLD, "%s: called w/mbuf (%p,%d)", __func__, m, off);
1255
1256 ifp = m->m_pkthdr.rcvif;
1257
1258 ip6 = mtod(m, struct ip6_hdr *);
1259
1260 /* Pullup to appropriate size. */
1261 mld = (struct mld_hdr *)(mtod(m, uint8_t *) + off);
1262 if (mld->mld_type == MLD_LISTENER_QUERY &&
1263 icmp6len >= sizeof(struct mldv2_query)) {
1264 mldlen = sizeof(struct mldv2_query);
1265 } else {
1266 mldlen = sizeof(struct mld_hdr);
1267 }
1268 IP6_EXTHDR_GET(mld, struct mld_hdr *, m, off, mldlen);
1269 if (mld == NULL) {
1270 ICMP6STAT_INC(icp6s_badlen);
1271 return (IPPROTO_DONE);
1272 }
1273
1274 /*
1275 * Userland needs to see all of this traffic for implementing
1276 * the endpoint discovery portion of multicast routing.
1277 */
1278 switch (mld->mld_type) {
1279 case MLD_LISTENER_QUERY:
1280 icmp6_ifstat_inc(ifp, ifs6_in_mldquery);
1281 if (icmp6len == sizeof(struct mld_hdr)) {
1282 if (mld_v1_input_query(ifp, ip6, mld) != 0)
1283 return (0);
1284 } else if (icmp6len >= sizeof(struct mldv2_query)) {
1285 if (mld_v2_input_query(ifp, ip6, m, off,
1286 icmp6len) != 0)
1287 return (0);
1288 }
1289 break;
1290 case MLD_LISTENER_REPORT:
1291 icmp6_ifstat_inc(ifp, ifs6_in_mldreport);
1292 if (mld_v1_input_report(ifp, ip6, mld) != 0)
1293 return (0);
1294 break;
1295 case MLDV2_LISTENER_REPORT:
1296 icmp6_ifstat_inc(ifp, ifs6_in_mldreport);
1297 break;
1298 case MLD_LISTENER_DONE:
1299 icmp6_ifstat_inc(ifp, ifs6_in_mlddone);
1300 break;
1301 default:
1302 break;
1303 }
1304
1305 return (0);
1306 }
1307
1308 /*
1309 * Fast timeout handler (global).
1310 * VIMAGE: Timeout handlers are expected to service all vimages.
1311 */
1312 void
1313 mld_fasttimo(void)
1314 {
1315 VNET_ITERATOR_DECL(vnet_iter);
1316
1317 VNET_LIST_RLOCK_NOSLEEP();
1318 VNET_FOREACH(vnet_iter) {
1319 CURVNET_SET(vnet_iter);
1320 mld_fasttimo_vnet();
1321 CURVNET_RESTORE();
1322 }
1323 VNET_LIST_RUNLOCK_NOSLEEP();
1324 }
1325
1326 /*
1327 * Fast timeout handler (per-vnet).
1328 *
1329 * VIMAGE: Assume caller has set up our curvnet.
1330 */
1331 static void
1332 mld_fasttimo_vnet(void)
1333 {
1334 struct ifqueue scq; /* State-change packets */
1335 struct ifqueue qrq; /* Query response packets */
1336 struct ifnet *ifp;
1337 struct mld_ifinfo *mli;
1338 struct ifmultiaddr *ifma, *tifma;
1339 struct in6_multi *inm;
1340 int uri_fasthz;
1341
1342 uri_fasthz = 0;
1343
1344 /*
1345 * Quick check to see if any work needs to be done, in order to
1346 * minimize the overhead of fasttimo processing.
1347 * SMPng: XXX Unlocked reads.
1348 */
1349 if (!V_current_state_timers_running6 &&
1350 !V_interface_timers_running6 &&
1351 !V_state_change_timers_running6)
1352 return;
1353
1354 IN6_MULTI_LOCK();
1355 MLD_LOCK();
1356
1357 /*
1358 * MLDv2 General Query response timer processing.
1359 */
1360 if (V_interface_timers_running6) {
1361 CTR1(KTR_MLD, "%s: interface timers running", __func__);
1362
1363 V_interface_timers_running6 = 0;
1364 LIST_FOREACH(mli, &V_mli_head, mli_link) {
1365 if (mli->mli_v2_timer == 0) {
1366 /* Do nothing. */
1367 } else if (--mli->mli_v2_timer == 0) {
1368 mld_v2_dispatch_general_query(mli);
1369 } else {
1370 V_interface_timers_running6 = 1;
1371 }
1372 }
1373 }
1374
1375 if (!V_current_state_timers_running6 &&
1376 !V_state_change_timers_running6)
1377 goto out_locked;
1378
1379 V_current_state_timers_running6 = 0;
1380 V_state_change_timers_running6 = 0;
1381
1382 CTR1(KTR_MLD, "%s: state change timers running", __func__);
1383
1384 /*
1385 * MLD host report and state-change timer processing.
1386 * Note: Processing a v2 group timer may remove a node.
1387 */
1388 LIST_FOREACH(mli, &V_mli_head, mli_link) {
1389 ifp = mli->mli_ifp;
1390
1391 if (mli->mli_version == MLD_VERSION_2) {
1392 uri_fasthz = MLD_RANDOM_DELAY(mli->mli_uri *
1393 PR_FASTHZ);
1394
1395 memset(&qrq, 0, sizeof(struct ifqueue));
1396 IFQ_SET_MAXLEN(&qrq, MLD_MAX_G_GS_PACKETS);
1397
1398 memset(&scq, 0, sizeof(struct ifqueue));
1399 IFQ_SET_MAXLEN(&scq, MLD_MAX_STATE_CHANGE_PACKETS);
1400 }
1401
1402 IF_ADDR_LOCK(ifp);
1403 TAILQ_FOREACH_SAFE(ifma, &ifp->if_multiaddrs, ifma_link,
1404 tifma) {
1405 if (ifma->ifma_addr->sa_family != AF_INET6 ||
1406 ifma->ifma_protospec == NULL)
1407 continue;
1408 inm = (struct in6_multi *)ifma->ifma_protospec;
1409 switch (mli->mli_version) {
1410 case MLD_VERSION_1:
1411 /*
1412 * XXX Drop IF_ADDR lock temporarily to
1413 * avoid recursion caused by a potential
1414 * call by in6ifa_ifpforlinklocal().
1415 * rwlock candidate?
1416 */
1417 IF_ADDR_UNLOCK(ifp);
1418 mld_v1_process_group_timer(inm,
1419 mli->mli_version);
1420 IF_ADDR_LOCK(ifp);
1421 break;
1422 case MLD_VERSION_2:
1423 mld_v2_process_group_timers(mli, &qrq,
1424 &scq, inm, uri_fasthz);
1425 break;
1426 }
1427 }
1428 IF_ADDR_UNLOCK(ifp);
1429
1430 if (mli->mli_version == MLD_VERSION_2) {
1431 struct in6_multi *tinm;
1432
1433 mld_dispatch_queue(&qrq, 0);
1434 mld_dispatch_queue(&scq, 0);
1435
1436 /*
1437 * Free the in_multi reference(s) for
1438 * this lifecycle.
1439 */
1440 SLIST_FOREACH_SAFE(inm, &mli->mli_relinmhead,
1441 in6m_nrele, tinm) {
1442 SLIST_REMOVE_HEAD(&mli->mli_relinmhead,
1443 in6m_nrele);
1444 in6m_release_locked(inm);
1445 }
1446 }
1447 }
1448
1449 out_locked:
1450 MLD_UNLOCK();
1451 IN6_MULTI_UNLOCK();
1452 }
1453
1454 /*
1455 * Update host report group timer.
1456 * Will update the global pending timer flags.
1457 */
1458 static void
1459 mld_v1_process_group_timer(struct in6_multi *inm, const int version)
1460 {
1461 int report_timer_expired;
1462
1463 IN6_MULTI_LOCK_ASSERT();
1464 MLD_LOCK_ASSERT();
1465
1466 if (inm->in6m_timer == 0) {
1467 report_timer_expired = 0;
1468 } else if (--inm->in6m_timer == 0) {
1469 report_timer_expired = 1;
1470 } else {
1471 V_current_state_timers_running6 = 1;
1472 return;
1473 }
1474
1475 switch (inm->in6m_state) {
1476 case MLD_NOT_MEMBER:
1477 case MLD_SILENT_MEMBER:
1478 case MLD_IDLE_MEMBER:
1479 case MLD_LAZY_MEMBER:
1480 case MLD_SLEEPING_MEMBER:
1481 case MLD_AWAKENING_MEMBER:
1482 break;
1483 case MLD_REPORTING_MEMBER:
1484 if (report_timer_expired) {
1485 inm->in6m_state = MLD_IDLE_MEMBER;
1486 (void)mld_v1_transmit_report(inm,
1487 MLD_LISTENER_REPORT);
1488 }
1489 break;
1490 case MLD_G_QUERY_PENDING_MEMBER:
1491 case MLD_SG_QUERY_PENDING_MEMBER:
1492 case MLD_LEAVING_MEMBER:
1493 break;
1494 }
1495 }
1496
1497 /*
1498 * Update a group's timers for MLDv2.
1499 * Will update the global pending timer flags.
1500 * Note: Unlocked read from mli.
1501 */
1502 static void
1503 mld_v2_process_group_timers(struct mld_ifinfo *mli,
1504 struct ifqueue *qrq, struct ifqueue *scq,
1505 struct in6_multi *inm, const int uri_fasthz)
1506 {
1507 int query_response_timer_expired;
1508 int state_change_retransmit_timer_expired;
1509 #ifdef KTR
1510 char ip6tbuf[INET6_ADDRSTRLEN];
1511 #endif
1512
1513 IN6_MULTI_LOCK_ASSERT();
1514 MLD_LOCK_ASSERT();
1515
1516 query_response_timer_expired = 0;
1517 state_change_retransmit_timer_expired = 0;
1518
1519 /*
1520 * During a transition from compatibility mode back to MLDv2,
1521 * a group record in REPORTING state may still have its group
1522 * timer active. This is a no-op in this function; it is easier
1523 * to deal with it here than to complicate the slow-timeout path.
1524 */
1525 if (inm->in6m_timer == 0) {
1526 query_response_timer_expired = 0;
1527 } else if (--inm->in6m_timer == 0) {
1528 query_response_timer_expired = 1;
1529 } else {
1530 V_current_state_timers_running6 = 1;
1531 }
1532
1533 if (inm->in6m_sctimer == 0) {
1534 state_change_retransmit_timer_expired = 0;
1535 } else if (--inm->in6m_sctimer == 0) {
1536 state_change_retransmit_timer_expired = 1;
1537 } else {
1538 V_state_change_timers_running6 = 1;
1539 }
1540
1541 /* We are in fasttimo, so be quick about it. */
1542 if (!state_change_retransmit_timer_expired &&
1543 !query_response_timer_expired)
1544 return;
1545
1546 switch (inm->in6m_state) {
1547 case MLD_NOT_MEMBER:
1548 case MLD_SILENT_MEMBER:
1549 case MLD_SLEEPING_MEMBER:
1550 case MLD_LAZY_MEMBER:
1551 case MLD_AWAKENING_MEMBER:
1552 case MLD_IDLE_MEMBER:
1553 break;
1554 case MLD_G_QUERY_PENDING_MEMBER:
1555 case MLD_SG_QUERY_PENDING_MEMBER:
1556 /*
1557 * Respond to a previously pending Group-Specific
1558 * or Group-and-Source-Specific query by enqueueing
1559 * the appropriate Current-State report for
1560 * immediate transmission.
1561 */
1562 if (query_response_timer_expired) {
1563 int retval;
1564
1565 retval = mld_v2_enqueue_group_record(qrq, inm, 0, 1,
1566 (inm->in6m_state == MLD_SG_QUERY_PENDING_MEMBER),
1567 0);
1568 CTR2(KTR_MLD, "%s: enqueue record = %d",
1569 __func__, retval);
1570 inm->in6m_state = MLD_REPORTING_MEMBER;
1571 in6m_clear_recorded(inm);
1572 }
1573 /* FALLTHROUGH */
1574 case MLD_REPORTING_MEMBER:
1575 case MLD_LEAVING_MEMBER:
1576 if (state_change_retransmit_timer_expired) {
1577 /*
1578 * State-change retransmission timer fired.
1579 * If there are any further pending retransmissions,
1580 * set the global pending state-change flag, and
1581 * reset the timer.
1582 */
1583 if (--inm->in6m_scrv > 0) {
1584 inm->in6m_sctimer = uri_fasthz;
1585 V_state_change_timers_running6 = 1;
1586 }
1587 /*
1588 * Retransmit the previously computed state-change
1589 * report. If there are no further pending
1590 * retransmissions, the mbuf queue will be consumed.
1591 * Update T0 state to T1 as we have now sent
1592 * a state-change.
1593 */
1594 (void)mld_v2_merge_state_changes(inm, scq);
1595
1596 in6m_commit(inm);
1597 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
1598 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
1599 inm->in6m_ifp->if_xname);
1600
1601 /*
1602 * If we are leaving the group for good, make sure
1603 * we release MLD's reference to it.
1604 * This release must be deferred using a SLIST,
1605 * as we are called from a loop which traverses
1606 * the in_ifmultiaddr TAILQ.
1607 */
1608 if (inm->in6m_state == MLD_LEAVING_MEMBER &&
1609 inm->in6m_scrv == 0) {
1610 inm->in6m_state = MLD_NOT_MEMBER;
1611 SLIST_INSERT_HEAD(&mli->mli_relinmhead,
1612 inm, in6m_nrele);
1613 }
1614 }
1615 break;
1616 }
1617 }
1618
1619 /*
1620 * Switch to a different version on the given interface,
1621 * as per Section 9.12.
1622 */
1623 static void
1624 mld_set_version(struct mld_ifinfo *mli, const int version)
1625 {
1626 int old_version_timer;
1627
1628 MLD_LOCK_ASSERT();
1629
1630 CTR4(KTR_MLD, "%s: switching to v%d on ifp %p(%s)", __func__,
1631 version, mli->mli_ifp, mli->mli_ifp->if_xname);
1632
1633 if (version == MLD_VERSION_1) {
1634 /*
1635 * Compute the "Older Version Querier Present" timer as per
1636 * Section 9.12.
1637 */
1638 old_version_timer = (mli->mli_rv * mli->mli_qi) + mli->mli_qri;
1639 old_version_timer *= PR_SLOWHZ;
1640 mli->mli_v1_timer = old_version_timer;
1641 }
1642
1643 if (mli->mli_v1_timer > 0 && mli->mli_version != MLD_VERSION_1) {
1644 mli->mli_version = MLD_VERSION_1;
1645 mld_v2_cancel_link_timers(mli);
1646 }
1647 }
1648
1649 /*
1650 * Cancel pending MLDv2 timers for the given link and all groups
1651 * joined on it; state-change, general-query, and group-query timers.
1652 */
1653 static void
1654 mld_v2_cancel_link_timers(struct mld_ifinfo *mli)
1655 {
1656 struct ifmultiaddr *ifma;
1657 struct ifnet *ifp;
1658 struct in6_multi *inm;
1659
1660 CTR3(KTR_MLD, "%s: cancel v2 timers on ifp %p(%s)", __func__,
1661 mli->mli_ifp, mli->mli_ifp->if_xname);
1662
1663 IN6_MULTI_LOCK_ASSERT();
1664 MLD_LOCK_ASSERT();
1665
1666 /*
1667 * Fast-track this potentially expensive operation
1668 * by checking all the global 'timer pending' flags.
1669 */
1670 if (!V_interface_timers_running6 &&
1671 !V_state_change_timers_running6 &&
1672 !V_current_state_timers_running6)
1673 return;
1674
1675 mli->mli_v2_timer = 0;
1676
1677 ifp = mli->mli_ifp;
1678
1679 IF_ADDR_LOCK(ifp);
1680 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
1681 if (ifma->ifma_addr->sa_family != AF_INET6)
1682 continue;
1683 inm = (struct in6_multi *)ifma->ifma_protospec;
1684 switch (inm->in6m_state) {
1685 case MLD_NOT_MEMBER:
1686 case MLD_SILENT_MEMBER:
1687 case MLD_IDLE_MEMBER:
1688 case MLD_LAZY_MEMBER:
1689 case MLD_SLEEPING_MEMBER:
1690 case MLD_AWAKENING_MEMBER:
1691 break;
1692 case MLD_LEAVING_MEMBER:
1693 /*
1694 * If we are leaving the group and switching
1695 * version, we need to release the final
1696 * reference held for issuing the INCLUDE {}.
1697 *
1698 * SMPNG: Must drop and re-acquire IF_ADDR_LOCK
1699 * around in6m_release_locked(), as it is not
1700 * a recursive mutex.
1701 */
1702 IF_ADDR_UNLOCK(ifp);
1703 in6m_release_locked(inm);
1704 IF_ADDR_LOCK(ifp);
1705 /* FALLTHROUGH */
1706 case MLD_G_QUERY_PENDING_MEMBER:
1707 case MLD_SG_QUERY_PENDING_MEMBER:
1708 in6m_clear_recorded(inm);
1709 /* FALLTHROUGH */
1710 case MLD_REPORTING_MEMBER:
1711 inm->in6m_sctimer = 0;
1712 inm->in6m_timer = 0;
1713 inm->in6m_state = MLD_REPORTING_MEMBER;
1714 /*
1715 * Free any pending MLDv2 state-change records.
1716 */
1717 _IF_DRAIN(&inm->in6m_scq);
1718 break;
1719 }
1720 }
1721 IF_ADDR_UNLOCK(ifp);
1722 }
1723
1724 /*
1725 * Global slowtimo handler.
1726 * VIMAGE: Timeout handlers are expected to service all vimages.
1727 */
1728 void
1729 mld_slowtimo(void)
1730 {
1731 VNET_ITERATOR_DECL(vnet_iter);
1732
1733 VNET_LIST_RLOCK_NOSLEEP();
1734 VNET_FOREACH(vnet_iter) {
1735 CURVNET_SET(vnet_iter);
1736 mld_slowtimo_vnet();
1737 CURVNET_RESTORE();
1738 }
1739 VNET_LIST_RUNLOCK_NOSLEEP();
1740 }
1741
1742 /*
1743 * Per-vnet slowtimo handler.
1744 */
1745 static void
1746 mld_slowtimo_vnet(void)
1747 {
1748 struct mld_ifinfo *mli;
1749
1750 MLD_LOCK();
1751
1752 LIST_FOREACH(mli, &V_mli_head, mli_link) {
1753 mld_v1_process_querier_timers(mli);
1754 }
1755
1756 MLD_UNLOCK();
1757 }
1758
1759 /*
1760 * Update the Older Version Querier Present timers for a link.
1761 * See Section 9.12 of RFC 3810.
1762 */
1763 static void
1764 mld_v1_process_querier_timers(struct mld_ifinfo *mli)
1765 {
1766
1767 MLD_LOCK_ASSERT();
1768
1769 if (mli->mli_version != MLD_VERSION_2 && --mli->mli_v1_timer == 0) {
1770 /*
1771 * MLDv1 Querier Present timer expired; revert to MLDv2.
1772 */
1773 CTR5(KTR_MLD,
1774 "%s: transition from v%d -> v%d on %p(%s)",
1775 __func__, mli->mli_version, MLD_VERSION_2,
1776 mli->mli_ifp, mli->mli_ifp->if_xname);
1777 mli->mli_version = MLD_VERSION_2;
1778 }
1779 }
1780
1781 /*
1782 * Transmit an MLDv1 report immediately.
1783 */
1784 static int
1785 mld_v1_transmit_report(struct in6_multi *in6m, const int type)
1786 {
1787 struct ifnet *ifp;
1788 struct in6_ifaddr *ia;
1789 struct ip6_hdr *ip6;
1790 struct mbuf *mh, *md;
1791 struct mld_hdr *mld;
1792
1793 IN6_MULTI_LOCK_ASSERT();
1794 MLD_LOCK_ASSERT();
1795
1796 ifp = in6m->in6m_ifp;
1797 ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
1798 /* ia may be NULL if link-local address is tentative. */
1799
1800 MGETHDR(mh, M_DONTWAIT, MT_HEADER);
1801 if (mh == NULL) {
1802 if (ia != NULL)
1803 ifa_free(&ia->ia_ifa);
1804 return (ENOMEM);
1805 }
1806 MGET(md, M_DONTWAIT, MT_DATA);
1807 if (md == NULL) {
1808 m_free(mh);
1809 if (ia != NULL)
1810 ifa_free(&ia->ia_ifa);
1811 return (ENOMEM);
1812 }
1813 mh->m_next = md;
1814
1815 /*
1816 * FUTURE: Consider increasing alignment by ETHER_HDR_LEN, so
1817 * that ether_output() does not need to allocate another mbuf
1818 * for the header in the most common case.
1819 */
1820 MH_ALIGN(mh, sizeof(struct ip6_hdr));
1821 mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld_hdr);
1822 mh->m_len = sizeof(struct ip6_hdr);
1823
1824 ip6 = mtod(mh, struct ip6_hdr *);
1825 ip6->ip6_flow = 0;
1826 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
1827 ip6->ip6_vfc |= IPV6_VERSION;
1828 ip6->ip6_nxt = IPPROTO_ICMPV6;
1829 ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any;
1830 ip6->ip6_dst = in6m->in6m_addr;
1831
1832 md->m_len = sizeof(struct mld_hdr);
1833 mld = mtod(md, struct mld_hdr *);
1834 mld->mld_type = type;
1835 mld->mld_code = 0;
1836 mld->mld_cksum = 0;
1837 mld->mld_maxdelay = 0;
1838 mld->mld_reserved = 0;
1839 mld->mld_addr = in6m->in6m_addr;
1840 in6_clearscope(&mld->mld_addr);
1841 mld->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6,
1842 sizeof(struct ip6_hdr), sizeof(struct mld_hdr));
1843
1844 mld_save_context(mh, ifp);
1845 mh->m_flags |= M_MLDV1;
1846
1847 mld_dispatch_packet(mh);
1848
1849 if (ia != NULL)
1850 ifa_free(&ia->ia_ifa);
1851 return (0);
1852 }
1853
1854 /*
1855 * Process a state change from the upper layer for the given IPv6 group.
1856 *
1857 * Each socket holds a reference on the in_multi in its own ip_moptions.
1858 * The socket layer will have made the necessary updates to.the group
1859 * state, it is now up to MLD to issue a state change report if there
1860 * has been any change between T0 (when the last state-change was issued)
1861 * and T1 (now).
1862 *
1863 * We use the MLDv2 state machine at group level. The MLd module
1864 * however makes the decision as to which MLD protocol version to speak.
1865 * A state change *from* INCLUDE {} always means an initial join.
1866 * A state change *to* INCLUDE {} always means a final leave.
1867 *
1868 * If delay is non-zero, and the state change is an initial multicast
1869 * join, the state change report will be delayed by 'delay' ticks
1870 * in units of PR_FASTHZ if MLDv1 is active on the link; otherwise
1871 * the initial MLDv2 state change report will be delayed by whichever
1872 * is sooner, a pending state-change timer or delay itself.
1873 *
1874 * VIMAGE: curvnet should have been set by caller, as this routine
1875 * is called from the socket option handlers.
1876 */
1877 int
1878 mld_change_state(struct in6_multi *inm, const int delay)
1879 {
1880 struct mld_ifinfo *mli;
1881 struct ifnet *ifp;
1882 int error;
1883
1884 IN6_MULTI_LOCK_ASSERT();
1885
1886 error = 0;
1887
1888 /*
1889 * Try to detect if the upper layer just asked us to change state
1890 * for an interface which has now gone away.
1891 */
1892 KASSERT(inm->in6m_ifma != NULL, ("%s: no ifma", __func__));
1893 ifp = inm->in6m_ifma->ifma_ifp;
1894 if (ifp != NULL) {
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
1902 MLD_LOCK();
1903
1904 mli = MLD_IFINFO(ifp);
1905 KASSERT(mli != NULL, ("%s: no mld_ifinfo for ifp %p", __func__, ifp));
1906
1907 /*
1908 * If we detect a state transition to or from MCAST_UNDEFINED
1909 * for this group, then we are starting or finishing an MLD
1910 * life cycle for this group.
1911 */
1912 if (inm->in6m_st[1].iss_fmode != inm->in6m_st[0].iss_fmode) {
1913 CTR3(KTR_MLD, "%s: inm transition %d -> %d", __func__,
1914 inm->in6m_st[0].iss_fmode, inm->in6m_st[1].iss_fmode);
1915 if (inm->in6m_st[0].iss_fmode == MCAST_UNDEFINED) {
1916 CTR1(KTR_MLD, "%s: initial join", __func__);
1917 error = mld_initial_join(inm, mli, delay);
1918 goto out_locked;
1919 } else if (inm->in6m_st[1].iss_fmode == MCAST_UNDEFINED) {
1920 CTR1(KTR_MLD, "%s: final leave", __func__);
1921 mld_final_leave(inm, mli);
1922 goto out_locked;
1923 }
1924 } else {
1925 CTR1(KTR_MLD, "%s: filter set change", __func__);
1926 }
1927
1928 error = mld_handle_state_change(inm, mli);
1929
1930 out_locked:
1931 MLD_UNLOCK();
1932 return (error);
1933 }
1934
1935 /*
1936 * Perform the initial join for an MLD group.
1937 *
1938 * When joining a group:
1939 * If the group should have its MLD traffic suppressed, do nothing.
1940 * MLDv1 starts sending MLDv1 host membership reports.
1941 * MLDv2 will schedule an MLDv2 state-change report containing the
1942 * initial state of the membership.
1943 *
1944 * If the delay argument is non-zero, then we must delay sending the
1945 * initial state change for delay ticks (in units of PR_FASTHZ).
1946 */
1947 static int
1948 mld_initial_join(struct in6_multi *inm, struct mld_ifinfo *mli,
1949 const int delay)
1950 {
1951 struct ifnet *ifp;
1952 struct ifqueue *ifq;
1953 int error, retval, syncstates;
1954 int odelay;
1955 #ifdef KTR
1956 char ip6tbuf[INET6_ADDRSTRLEN];
1957 #endif
1958
1959 CTR4(KTR_MLD, "%s: initial join %s on ifp %p(%s)",
1960 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
1961 inm->in6m_ifp, inm->in6m_ifp->if_xname);
1962
1963 error = 0;
1964 syncstates = 1;
1965
1966 ifp = inm->in6m_ifp;
1967
1968 IN6_MULTI_LOCK_ASSERT();
1969 MLD_LOCK_ASSERT();
1970
1971 KASSERT(mli && mli->mli_ifp == ifp, ("%s: inconsistent ifp", __func__));
1972
1973 /*
1974 * Groups joined on loopback or marked as 'not reported',
1975 * enter the MLD_SILENT_MEMBER state and
1976 * are never reported in any protocol exchanges.
1977 * All other groups enter the appropriate state machine
1978 * for the version in use on this link.
1979 * A link marked as MLIF_SILENT causes MLD to be completely
1980 * disabled for the link.
1981 */
1982 if ((ifp->if_flags & IFF_LOOPBACK) ||
1983 (mli->mli_flags & MLIF_SILENT) ||
1984 !mld_is_addr_reported(&inm->in6m_addr)) {
1985 CTR1(KTR_MLD,
1986 "%s: not kicking state machine for silent group", __func__);
1987 inm->in6m_state = MLD_SILENT_MEMBER;
1988 inm->in6m_timer = 0;
1989 } else {
1990 /*
1991 * Deal with overlapping in_multi lifecycle.
1992 * If this group was LEAVING, then make sure
1993 * we drop the reference we picked up to keep the
1994 * group around for the final INCLUDE {} enqueue.
1995 */
1996 if (mli->mli_version == MLD_VERSION_2 &&
1997 inm->in6m_state == MLD_LEAVING_MEMBER)
1998 in6m_release_locked(inm);
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 * PR_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 error = mld_v1_transmit_report(inm,
2018 MLD_LISTENER_REPORT);
2019 if (error == 0) {
2020 inm->in6m_timer = odelay;
2021 V_current_state_timers_running6 = 1;
2022 }
2023 }
2024 break;
2025
2026 case MLD_VERSION_2:
2027 /*
2028 * Defer update of T0 to T1, until the first copy
2029 * of the state change has been transmitted.
2030 */
2031 syncstates = 0;
2032
2033 /*
2034 * Immediately enqueue a State-Change Report for
2035 * this interface, freeing any previous reports.
2036 * Don't kick the timers if there is nothing to do,
2037 * or if an error occurred.
2038 */
2039 ifq = &inm->in6m_scq;
2040 _IF_DRAIN(ifq);
2041 retval = mld_v2_enqueue_group_record(ifq, inm, 1,
2042 0, 0, (mli->mli_flags & MLIF_USEALLOW));
2043 CTR2(KTR_MLD, "%s: enqueue record = %d",
2044 __func__, retval);
2045 if (retval <= 0) {
2046 error = retval * -1;
2047 break;
2048 }
2049
2050 /*
2051 * Schedule transmission of pending state-change
2052 * report up to RV times for this link. The timer
2053 * will fire at the next mld_fasttimo (~200ms),
2054 * giving us an opportunity to merge the reports.
2055 *
2056 * If a delay was provided to this function, only
2057 * use this delay if sooner than the existing one.
2058 */
2059 KASSERT(mli->mli_rv > 1,
2060 ("%s: invalid robustness %d", __func__,
2061 mli->mli_rv));
2062 inm->in6m_scrv = mli->mli_rv;
2063 if (delay) {
2064 if (inm->in6m_sctimer > 1) {
2065 inm->in6m_sctimer =
2066 min(inm->in6m_sctimer, delay);
2067 } else
2068 inm->in6m_sctimer = delay;
2069 } else
2070 inm->in6m_sctimer = 1;
2071 V_state_change_timers_running6 = 1;
2072
2073 error = 0;
2074 break;
2075 }
2076 }
2077
2078 /*
2079 * Only update the T0 state if state change is atomic,
2080 * i.e. we don't need to wait for a timer to fire before we
2081 * can consider the state change to have been communicated.
2082 */
2083 if (syncstates) {
2084 in6m_commit(inm);
2085 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
2086 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2087 inm->in6m_ifp->if_xname);
2088 }
2089
2090 return (error);
2091 }
2092
2093 /*
2094 * Issue an intermediate state change during the life-cycle.
2095 */
2096 static int
2097 mld_handle_state_change(struct in6_multi *inm, struct mld_ifinfo *mli)
2098 {
2099 struct ifnet *ifp;
2100 int retval;
2101 #ifdef KTR
2102 char ip6tbuf[INET6_ADDRSTRLEN];
2103 #endif
2104
2105 CTR4(KTR_MLD, "%s: state change for %s on ifp %p(%s)",
2106 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2107 inm->in6m_ifp, inm->in6m_ifp->if_xname);
2108
2109 ifp = inm->in6m_ifp;
2110
2111 IN6_MULTI_LOCK_ASSERT();
2112 MLD_LOCK_ASSERT();
2113
2114 KASSERT(mli && mli->mli_ifp == ifp,
2115 ("%s: inconsistent ifp", __func__));
2116
2117 if ((ifp->if_flags & IFF_LOOPBACK) ||
2118 (mli->mli_flags & MLIF_SILENT) ||
2119 !mld_is_addr_reported(&inm->in6m_addr) ||
2120 (mli->mli_version != MLD_VERSION_2)) {
2121 if (!mld_is_addr_reported(&inm->in6m_addr)) {
2122 CTR1(KTR_MLD,
2123 "%s: not kicking state machine for silent group", __func__);
2124 }
2125 CTR1(KTR_MLD, "%s: nothing to do", __func__);
2126 in6m_commit(inm);
2127 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
2128 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2129 inm->in6m_ifp->if_xname);
2130 return (0);
2131 }
2132
2133 _IF_DRAIN(&inm->in6m_scq);
2134
2135 retval = mld_v2_enqueue_group_record(&inm->in6m_scq, inm, 1, 0, 0,
2136 (mli->mli_flags & MLIF_USEALLOW));
2137 CTR2(KTR_MLD, "%s: enqueue record = %d", __func__, retval);
2138 if (retval <= 0)
2139 return (-retval);
2140
2141 /*
2142 * If record(s) were enqueued, start the state-change
2143 * report timer for this group.
2144 */
2145 inm->in6m_scrv = mli->mli_rv;
2146 inm->in6m_sctimer = 1;
2147 V_state_change_timers_running6 = 1;
2148
2149 return (0);
2150 }
2151
2152 /*
2153 * Perform the final leave for a multicast address.
2154 *
2155 * When leaving a group:
2156 * MLDv1 sends a DONE message, if and only if we are the reporter.
2157 * MLDv2 enqueues a state-change report containing a transition
2158 * to INCLUDE {} for immediate transmission.
2159 */
2160 static void
2161 mld_final_leave(struct in6_multi *inm, struct mld_ifinfo *mli)
2162 {
2163 int syncstates;
2164 #ifdef KTR
2165 char ip6tbuf[INET6_ADDRSTRLEN];
2166 #endif
2167
2168 syncstates = 1;
2169
2170 CTR4(KTR_MLD, "%s: final leave %s on ifp %p(%s)",
2171 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2172 inm->in6m_ifp, inm->in6m_ifp->if_xname);
2173
2174 IN6_MULTI_LOCK_ASSERT();
2175 MLD_LOCK_ASSERT();
2176
2177 switch (inm->in6m_state) {
2178 case MLD_NOT_MEMBER:
2179 case MLD_SILENT_MEMBER:
2180 case MLD_LEAVING_MEMBER:
2181 /* Already leaving or left; do nothing. */
2182 CTR1(KTR_MLD,
2183 "%s: not kicking state machine for silent group", __func__);
2184 break;
2185 case MLD_REPORTING_MEMBER:
2186 case MLD_IDLE_MEMBER:
2187 case MLD_G_QUERY_PENDING_MEMBER:
2188 case MLD_SG_QUERY_PENDING_MEMBER:
2189 if (mli->mli_version == MLD_VERSION_1) {
2190 #ifdef INVARIANTS
2191 if (inm->in6m_state == MLD_G_QUERY_PENDING_MEMBER ||
2192 inm->in6m_state == MLD_SG_QUERY_PENDING_MEMBER)
2193 panic("%s: MLDv2 state reached, not MLDv2 mode",
2194 __func__);
2195 #endif
2196 mld_v1_transmit_report(inm, MLD_LISTENER_DONE);
2197 inm->in6m_state = MLD_NOT_MEMBER;
2198 } else if (mli->mli_version == MLD_VERSION_2) {
2199 /*
2200 * Stop group timer and all pending reports.
2201 * Immediately enqueue a state-change report
2202 * TO_IN {} to be sent on the next fast timeout,
2203 * giving us an opportunity to merge reports.
2204 */
2205 _IF_DRAIN(&inm->in6m_scq);
2206 inm->in6m_timer = 0;
2207 inm->in6m_scrv = mli->mli_rv;
2208 CTR4(KTR_MLD, "%s: Leaving %s/%s with %d "
2209 "pending retransmissions.", __func__,
2210 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2211 inm->in6m_ifp->if_xname, inm->in6m_scrv);
2212 if (inm->in6m_scrv == 0) {
2213 inm->in6m_state = MLD_NOT_MEMBER;
2214 inm->in6m_sctimer = 0;
2215 } else {
2216 int retval;
2217
2218 in6m_acquire_locked(inm);
2219
2220 retval = mld_v2_enqueue_group_record(
2221 &inm->in6m_scq, inm, 1, 0, 0,
2222 (mli->mli_flags & MLIF_USEALLOW));
2223 KASSERT(retval != 0,
2224 ("%s: enqueue record = %d", __func__,
2225 retval));
2226
2227 inm->in6m_state = MLD_LEAVING_MEMBER;
2228 inm->in6m_sctimer = 1;
2229 V_state_change_timers_running6 = 1;
2230 syncstates = 0;
2231 }
2232 break;
2233 }
2234 break;
2235 case MLD_LAZY_MEMBER:
2236 case MLD_SLEEPING_MEMBER:
2237 case MLD_AWAKENING_MEMBER:
2238 /* Our reports are suppressed; do nothing. */
2239 break;
2240 }
2241
2242 if (syncstates) {
2243 in6m_commit(inm);
2244 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
2245 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2246 inm->in6m_ifp->if_xname);
2247 inm->in6m_st[1].iss_fmode = MCAST_UNDEFINED;
2248 CTR3(KTR_MLD, "%s: T1 now MCAST_UNDEFINED for %p/%s",
2249 __func__, &inm->in6m_addr, inm->in6m_ifp->if_xname);
2250 }
2251 }
2252
2253 /*
2254 * Enqueue an MLDv2 group record to the given output queue.
2255 *
2256 * If is_state_change is zero, a current-state record is appended.
2257 * If is_state_change is non-zero, a state-change report is appended.
2258 *
2259 * If is_group_query is non-zero, an mbuf packet chain is allocated.
2260 * If is_group_query is zero, and if there is a packet with free space
2261 * at the tail of the queue, it will be appended to providing there
2262 * is enough free space.
2263 * Otherwise a new mbuf packet chain is allocated.
2264 *
2265 * If is_source_query is non-zero, each source is checked to see if
2266 * it was recorded for a Group-Source query, and will be omitted if
2267 * it is not both in-mode and recorded.
2268 *
2269 * If use_block_allow is non-zero, state change reports for initial join
2270 * and final leave, on an inclusive mode group with a source list, will be
2271 * rewritten to use the ALLOW_NEW and BLOCK_OLD record types, respectively.
2272 *
2273 * The function will attempt to allocate leading space in the packet
2274 * for the IPv6+ICMP headers to be prepended without fragmenting the chain.
2275 *
2276 * If successful the size of all data appended to the queue is returned,
2277 * otherwise an error code less than zero is returned, or zero if
2278 * no record(s) were appended.
2279 */
2280 static int
2281 mld_v2_enqueue_group_record(struct ifqueue *ifq, struct in6_multi *inm,
2282 const int is_state_change, const int is_group_query,
2283 const int is_source_query, const int use_block_allow)
2284 {
2285 struct mldv2_record mr;
2286 struct mldv2_record *pmr;
2287 struct ifnet *ifp;
2288 struct ip6_msource *ims, *nims;
2289 struct mbuf *m0, *m, *md;
2290 int error, is_filter_list_change;
2291 int minrec0len, m0srcs, msrcs, nbytes, off;
2292 int record_has_sources;
2293 int now;
2294 int type;
2295 uint8_t mode;
2296 #ifdef KTR
2297 char ip6tbuf[INET6_ADDRSTRLEN];
2298 #endif
2299
2300 IN6_MULTI_LOCK_ASSERT();
2301
2302 error = 0;
2303 ifp = inm->in6m_ifp;
2304 is_filter_list_change = 0;
2305 m = NULL;
2306 m0 = NULL;
2307 m0srcs = 0;
2308 msrcs = 0;
2309 nbytes = 0;
2310 nims = NULL;
2311 record_has_sources = 1;
2312 pmr = NULL;
2313 type = MLD_DO_NOTHING;
2314 mode = inm->in6m_st[1].iss_fmode;
2315
2316 /*
2317 * If we did not transition out of ASM mode during t0->t1,
2318 * and there are no source nodes to process, we can skip
2319 * the generation of source records.
2320 */
2321 if (inm->in6m_st[0].iss_asm > 0 && inm->in6m_st[1].iss_asm > 0 &&
2322 inm->in6m_nsrc == 0)
2323 record_has_sources = 0;
2324
2325 if (is_state_change) {
2326 /*
2327 * Queue a state change record.
2328 * If the mode did not change, and there are non-ASM
2329 * listeners or source filters present,
2330 * we potentially need to issue two records for the group.
2331 * If there are ASM listeners, and there was no filter
2332 * mode transition of any kind, do nothing.
2333 *
2334 * If we are transitioning to MCAST_UNDEFINED, we need
2335 * not send any sources. A transition to/from this state is
2336 * considered inclusive with some special treatment.
2337 *
2338 * If we are rewriting initial joins/leaves to use
2339 * ALLOW/BLOCK, and the group's membership is inclusive,
2340 * we need to send sources in all cases.
2341 */
2342 if (mode != inm->in6m_st[0].iss_fmode) {
2343 if (mode == MCAST_EXCLUDE) {
2344 CTR1(KTR_MLD, "%s: change to EXCLUDE",
2345 __func__);
2346 type = MLD_CHANGE_TO_EXCLUDE_MODE;
2347 } else {
2348 CTR1(KTR_MLD, "%s: change to INCLUDE",
2349 __func__);
2350 if (use_block_allow) {
2351 /*
2352 * XXX
2353 * Here we're interested in state
2354 * edges either direction between
2355 * MCAST_UNDEFINED and MCAST_INCLUDE.
2356 * Perhaps we should just check
2357 * the group state, rather than
2358 * the filter mode.
2359 */
2360 if (mode == MCAST_UNDEFINED) {
2361 type = MLD_BLOCK_OLD_SOURCES;
2362 } else {
2363 type = MLD_ALLOW_NEW_SOURCES;
2364 }
2365 } else {
2366 type = MLD_CHANGE_TO_INCLUDE_MODE;
2367 if (mode == MCAST_UNDEFINED)
2368 record_has_sources = 0;
2369 }
2370 }
2371 } else {
2372 if (record_has_sources) {
2373 is_filter_list_change = 1;
2374 } else {
2375 type = MLD_DO_NOTHING;
2376 }
2377 }
2378 } else {
2379 /*
2380 * Queue a current state record.
2381 */
2382 if (mode == MCAST_EXCLUDE) {
2383 type = MLD_MODE_IS_EXCLUDE;
2384 } else if (mode == MCAST_INCLUDE) {
2385 type = MLD_MODE_IS_INCLUDE;
2386 KASSERT(inm->in6m_st[1].iss_asm == 0,
2387 ("%s: inm %p is INCLUDE but ASM count is %d",
2388 __func__, inm, inm->in6m_st[1].iss_asm));
2389 }
2390 }
2391
2392 /*
2393 * Generate the filter list changes using a separate function.
2394 */
2395 if (is_filter_list_change)
2396 return (mld_v2_enqueue_filter_change(ifq, inm));
2397
2398 if (type == MLD_DO_NOTHING) {
2399 CTR3(KTR_MLD, "%s: nothing to do for %s/%s",
2400 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2401 inm->in6m_ifp->if_xname);
2402 return (0);
2403 }
2404
2405 /*
2406 * If any sources are present, we must be able to fit at least
2407 * one in the trailing space of the tail packet's mbuf,
2408 * ideally more.
2409 */
2410 minrec0len = sizeof(struct mldv2_record);
2411 if (record_has_sources)
2412 minrec0len += sizeof(struct in6_addr);
2413
2414 CTR4(KTR_MLD, "%s: queueing %s for %s/%s", __func__,
2415 mld_rec_type_to_str(type),
2416 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2417 inm->in6m_ifp->if_xname);
2418
2419 /*
2420 * Check if we have a packet in the tail of the queue for this
2421 * group into which the first group record for this group will fit.
2422 * Otherwise allocate a new packet.
2423 * Always allocate leading space for IP6+RA+ICMPV6+REPORT.
2424 * Note: Group records for G/GSR query responses MUST be sent
2425 * in their own packet.
2426 */
2427 m0 = ifq->ifq_tail;
2428 if (!is_group_query &&
2429 m0 != NULL &&
2430 (m0->m_pkthdr.PH_vt.vt_nrecs + 1 <= MLD_V2_REPORT_MAXRECS) &&
2431 (m0->m_pkthdr.len + minrec0len) <
2432 (ifp->if_mtu - MLD_MTUSPACE)) {
2433 m0srcs = (ifp->if_mtu - m0->m_pkthdr.len -
2434 sizeof(struct mldv2_record)) /
2435 sizeof(struct in6_addr);
2436 m = m0;
2437 CTR1(KTR_MLD, "%s: use existing packet", __func__);
2438 } else {
2439 if (_IF_QFULL(ifq)) {
2440 CTR1(KTR_MLD, "%s: outbound queue full", __func__);
2441 return (-ENOMEM);
2442 }
2443 m = NULL;
2444 m0srcs = (ifp->if_mtu - MLD_MTUSPACE -
2445 sizeof(struct mldv2_record)) / sizeof(struct in6_addr);
2446 if (!is_state_change && !is_group_query)
2447 m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
2448 if (m == NULL)
2449 m = m_gethdr(M_DONTWAIT, MT_DATA);
2450 if (m == NULL)
2451 return (-ENOMEM);
2452
2453 mld_save_context(m, ifp);
2454
2455 CTR1(KTR_MLD, "%s: allocated first packet", __func__);
2456 }
2457
2458 /*
2459 * Append group record.
2460 * If we have sources, we don't know how many yet.
2461 */
2462 mr.mr_type = type;
2463 mr.mr_datalen = 0;
2464 mr.mr_numsrc = 0;
2465 mr.mr_addr = inm->in6m_addr;
2466 in6_clearscope(&mr.mr_addr);
2467 if (!m_append(m, sizeof(struct mldv2_record), (void *)&mr)) {
2468 if (m != m0)
2469 m_freem(m);
2470 CTR1(KTR_MLD, "%s: m_append() failed.", __func__);
2471 return (-ENOMEM);
2472 }
2473 nbytes += sizeof(struct mldv2_record);
2474
2475 /*
2476 * Append as many sources as will fit in the first packet.
2477 * If we are appending to a new packet, the chain allocation
2478 * may potentially use clusters; use m_getptr() in this case.
2479 * If we are appending to an existing packet, we need to obtain
2480 * a pointer to the group record after m_append(), in case a new
2481 * mbuf was allocated.
2482 *
2483 * Only append sources which are in-mode at t1. If we are
2484 * transitioning to MCAST_UNDEFINED state on the group, and
2485 * use_block_allow is zero, do not include source entries.
2486 * Otherwise, we need to include this source in the report.
2487 *
2488 * Only report recorded sources in our filter set when responding
2489 * to a group-source query.
2490 */
2491 if (record_has_sources) {
2492 if (m == m0) {
2493 md = m_last(m);
2494 pmr = (struct mldv2_record *)(mtod(md, uint8_t *) +
2495 md->m_len - nbytes);
2496 } else {
2497 md = m_getptr(m, 0, &off);
2498 pmr = (struct mldv2_record *)(mtod(md, uint8_t *) +
2499 off);
2500 }
2501 msrcs = 0;
2502 RB_FOREACH_SAFE(ims, ip6_msource_tree, &inm->in6m_srcs,
2503 nims) {
2504 CTR2(KTR_MLD, "%s: visit node %s", __func__,
2505 ip6_sprintf(ip6tbuf, &ims->im6s_addr));
2506 now = im6s_get_mode(inm, ims, 1);
2507 CTR2(KTR_MLD, "%s: node is %d", __func__, now);
2508 if ((now != mode) ||
2509 (now == mode &&
2510 (!use_block_allow && mode == MCAST_UNDEFINED))) {
2511 CTR1(KTR_MLD, "%s: skip node", __func__);
2512 continue;
2513 }
2514 if (is_source_query && ims->im6s_stp == 0) {
2515 CTR1(KTR_MLD, "%s: skip unrecorded node",
2516 __func__);
2517 continue;
2518 }
2519 CTR1(KTR_MLD, "%s: append node", __func__);
2520 if (!m_append(m, sizeof(struct in6_addr),
2521 (void *)&ims->im6s_addr)) {
2522 if (m != m0)
2523 m_freem(m);
2524 CTR1(KTR_MLD, "%s: m_append() failed.",
2525 __func__);
2526 return (-ENOMEM);
2527 }
2528 nbytes += sizeof(struct in6_addr);
2529 ++msrcs;
2530 if (msrcs == m0srcs)
2531 break;
2532 }
2533 CTR2(KTR_MLD, "%s: msrcs is %d this packet", __func__,
2534 msrcs);
2535 pmr->mr_numsrc = htons(msrcs);
2536 nbytes += (msrcs * sizeof(struct in6_addr));
2537 }
2538
2539 if (is_source_query && msrcs == 0) {
2540 CTR1(KTR_MLD, "%s: no recorded sources to report", __func__);
2541 if (m != m0)
2542 m_freem(m);
2543 return (0);
2544 }
2545
2546 /*
2547 * We are good to go with first packet.
2548 */
2549 if (m != m0) {
2550 CTR1(KTR_MLD, "%s: enqueueing first packet", __func__);
2551 m->m_pkthdr.PH_vt.vt_nrecs = 1;
2552 _IF_ENQUEUE(ifq, m);
2553 } else
2554 m->m_pkthdr.PH_vt.vt_nrecs++;
2555
2556 /*
2557 * No further work needed if no source list in packet(s).
2558 */
2559 if (!record_has_sources)
2560 return (nbytes);
2561
2562 /*
2563 * Whilst sources remain to be announced, we need to allocate
2564 * a new packet and fill out as many sources as will fit.
2565 * Always try for a cluster first.
2566 */
2567 while (nims != NULL) {
2568 if (_IF_QFULL(ifq)) {
2569 CTR1(KTR_MLD, "%s: outbound queue full", __func__);
2570 return (-ENOMEM);
2571 }
2572 m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
2573 if (m == NULL)
2574 m = m_gethdr(M_DONTWAIT, MT_DATA);
2575 if (m == NULL)
2576 return (-ENOMEM);
2577 mld_save_context(m, ifp);
2578 md = m_getptr(m, 0, &off);
2579 pmr = (struct mldv2_record *)(mtod(md, uint8_t *) + off);
2580 CTR1(KTR_MLD, "%s: allocated next packet", __func__);
2581
2582 if (!m_append(m, sizeof(struct mldv2_record), (void *)&mr)) {
2583 if (m != m0)
2584 m_freem(m);
2585 CTR1(KTR_MLD, "%s: m_append() failed.", __func__);
2586 return (-ENOMEM);
2587 }
2588 m->m_pkthdr.PH_vt.vt_nrecs = 1;
2589 nbytes += sizeof(struct mldv2_record);
2590
2591 m0srcs = (ifp->if_mtu - MLD_MTUSPACE -
2592 sizeof(struct mldv2_record)) / sizeof(struct in6_addr);
2593
2594 msrcs = 0;
2595 RB_FOREACH_FROM(ims, ip6_msource_tree, nims) {
2596 CTR2(KTR_MLD, "%s: visit node %s",
2597 __func__, ip6_sprintf(ip6tbuf, &ims->im6s_addr));
2598 now = im6s_get_mode(inm, ims, 1);
2599 if ((now != mode) ||
2600 (now == mode &&
2601 (!use_block_allow && mode == MCAST_UNDEFINED))) {
2602 CTR1(KTR_MLD, "%s: skip node", __func__);
2603 continue;
2604 }
2605 if (is_source_query && ims->im6s_stp == 0) {
2606 CTR1(KTR_MLD, "%s: skip unrecorded node",
2607 __func__);
2608 continue;
2609 }
2610 CTR1(KTR_MLD, "%s: append node", __func__);
2611 if (!m_append(m, sizeof(struct in6_addr),
2612 (void *)&ims->im6s_addr)) {
2613 if (m != m0)
2614 m_freem(m);
2615 CTR1(KTR_MLD, "%s: m_append() failed.",
2616 __func__);
2617 return (-ENOMEM);
2618 }
2619 ++msrcs;
2620 if (msrcs == m0srcs)
2621 break;
2622 }
2623 pmr->mr_numsrc = htons(msrcs);
2624 nbytes += (msrcs * sizeof(struct in6_addr));
2625
2626 CTR1(KTR_MLD, "%s: enqueueing next packet", __func__);
2627 _IF_ENQUEUE(ifq, m);
2628 }
2629
2630 return (nbytes);
2631 }
2632
2633 /*
2634 * Type used to mark record pass completion.
2635 * We exploit the fact we can cast to this easily from the
2636 * current filter modes on each ip_msource node.
2637 */
2638 typedef enum {
2639 REC_NONE = 0x00, /* MCAST_UNDEFINED */
2640 REC_ALLOW = 0x01, /* MCAST_INCLUDE */
2641 REC_BLOCK = 0x02, /* MCAST_EXCLUDE */
2642 REC_FULL = REC_ALLOW | REC_BLOCK
2643 } rectype_t;
2644
2645 /*
2646 * Enqueue an MLDv2 filter list change to the given output queue.
2647 *
2648 * Source list filter state is held in an RB-tree. When the filter list
2649 * for a group is changed without changing its mode, we need to compute
2650 * the deltas between T0 and T1 for each source in the filter set,
2651 * and enqueue the appropriate ALLOW_NEW/BLOCK_OLD records.
2652 *
2653 * As we may potentially queue two record types, and the entire R-B tree
2654 * needs to be walked at once, we break this out into its own function
2655 * so we can generate a tightly packed queue of packets.
2656 *
2657 * XXX This could be written to only use one tree walk, although that makes
2658 * serializing into the mbuf chains a bit harder. For now we do two walks
2659 * which makes things easier on us, and it may or may not be harder on
2660 * the L2 cache.
2661 *
2662 * If successful the size of all data appended to the queue is returned,
2663 * otherwise an error code less than zero is returned, or zero if
2664 * no record(s) were appended.
2665 */
2666 static int
2667 mld_v2_enqueue_filter_change(struct ifqueue *ifq, struct in6_multi *inm)
2668 {
2669 static const int MINRECLEN =
2670 sizeof(struct mldv2_record) + sizeof(struct in6_addr);
2671 struct ifnet *ifp;
2672 struct mldv2_record mr;
2673 struct mldv2_record *pmr;
2674 struct ip6_msource *ims, *nims;
2675 struct mbuf *m, *m0, *md;
2676 int m0srcs, nbytes, npbytes, off, rsrcs, schanged;
2677 int nallow, nblock;
2678 uint8_t mode, now, then;
2679 rectype_t crt, drt, nrt;
2680 #ifdef KTR
2681 char ip6tbuf[INET6_ADDRSTRLEN];
2682 #endif
2683
2684 IN6_MULTI_LOCK_ASSERT();
2685
2686 if (inm->in6m_nsrc == 0 ||
2687 (inm->in6m_st[0].iss_asm > 0 && inm->in6m_st[1].iss_asm > 0))
2688 return (0);
2689
2690 ifp = inm->in6m_ifp; /* interface */
2691 mode = inm->in6m_st[1].iss_fmode; /* filter mode at t1 */
2692 crt = REC_NONE; /* current group record type */
2693 drt = REC_NONE; /* mask of completed group record types */
2694 nrt = REC_NONE; /* record type for current node */
2695 m0srcs = 0; /* # source which will fit in current mbuf chain */
2696 npbytes = 0; /* # of bytes appended this packet */
2697 nbytes = 0; /* # of bytes appended to group's state-change queue */
2698 rsrcs = 0; /* # sources encoded in current record */
2699 schanged = 0; /* # nodes encoded in overall filter change */
2700 nallow = 0; /* # of source entries in ALLOW_NEW */
2701 nblock = 0; /* # of source entries in BLOCK_OLD */
2702 nims = NULL; /* next tree node pointer */
2703
2704 /*
2705 * For each possible filter record mode.
2706 * The first kind of source we encounter tells us which
2707 * is the first kind of record we start appending.
2708 * If a node transitioned to UNDEFINED at t1, its mode is treated
2709 * as the inverse of the group's filter mode.
2710 */
2711 while (drt != REC_FULL) {
2712 do {
2713 m0 = ifq->ifq_tail;
2714 if (m0 != NULL &&
2715 (m0->m_pkthdr.PH_vt.vt_nrecs + 1 <=
2716 MLD_V2_REPORT_MAXRECS) &&
2717 (m0->m_pkthdr.len + MINRECLEN) <
2718 (ifp->if_mtu - MLD_MTUSPACE)) {
2719 m = m0;
2720 m0srcs = (ifp->if_mtu - m0->m_pkthdr.len -
2721 sizeof(struct mldv2_record)) /
2722 sizeof(struct in6_addr);
2723 CTR1(KTR_MLD,
2724 "%s: use previous packet", __func__);
2725 } else {
2726 m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
2727 if (m == NULL)
2728 m = m_gethdr(M_DONTWAIT, MT_DATA);
2729 if (m == NULL) {
2730 CTR1(KTR_MLD,
2731 "%s: m_get*() failed", __func__);
2732 return (-ENOMEM);
2733 }
2734 m->m_pkthdr.PH_vt.vt_nrecs = 0;
2735 mld_save_context(m, ifp);
2736 m0srcs = (ifp->if_mtu - MLD_MTUSPACE -
2737 sizeof(struct mldv2_record)) /
2738 sizeof(struct in6_addr);
2739 npbytes = 0;
2740 CTR1(KTR_MLD,
2741 "%s: allocated new packet", __func__);
2742 }
2743 /*
2744 * Append the MLD group record header to the
2745 * current packet's data area.
2746 * Recalculate pointer to free space for next
2747 * group record, in case m_append() allocated
2748 * a new mbuf or cluster.
2749 */
2750 memset(&mr, 0, sizeof(mr));
2751 mr.mr_addr = inm->in6m_addr;
2752 in6_clearscope(&mr.mr_addr);
2753 if (!m_append(m, sizeof(mr), (void *)&mr)) {
2754 if (m != m0)
2755 m_freem(m);
2756 CTR1(KTR_MLD,
2757 "%s: m_append() failed", __func__);
2758 return (-ENOMEM);
2759 }
2760 npbytes += sizeof(struct mldv2_record);
2761 if (m != m0) {
2762 /* new packet; offset in chain */
2763 md = m_getptr(m, npbytes -
2764 sizeof(struct mldv2_record), &off);
2765 pmr = (struct mldv2_record *)(mtod(md,
2766 uint8_t *) + off);
2767 } else {
2768 /* current packet; offset from last append */
2769 md = m_last(m);
2770 pmr = (struct mldv2_record *)(mtod(md,
2771 uint8_t *) + md->m_len -
2772 sizeof(struct mldv2_record));
2773 }
2774 /*
2775 * Begin walking the tree for this record type
2776 * pass, or continue from where we left off
2777 * previously if we had to allocate a new packet.
2778 * Only report deltas in-mode at t1.
2779 * We need not report included sources as allowed
2780 * if we are in inclusive mode on the group,
2781 * however the converse is not true.
2782 */
2783 rsrcs = 0;
2784 if (nims == NULL) {
2785 nims = RB_MIN(ip6_msource_tree,
2786 &inm->in6m_srcs);
2787 }
2788 RB_FOREACH_FROM(ims, ip6_msource_tree, nims) {
2789 CTR2(KTR_MLD, "%s: visit node %s", __func__,
2790 ip6_sprintf(ip6tbuf, &ims->im6s_addr));
2791 now = im6s_get_mode(inm, ims, 1);
2792 then = im6s_get_mode(inm, ims, 0);
2793 CTR3(KTR_MLD, "%s: mode: t0 %d, t1 %d",
2794 __func__, then, now);
2795 if (now == then) {
2796 CTR1(KTR_MLD,
2797 "%s: skip unchanged", __func__);
2798 continue;
2799 }
2800 if (mode == MCAST_EXCLUDE &&
2801 now == MCAST_INCLUDE) {
2802 CTR1(KTR_MLD,
2803 "%s: skip IN src on EX group",
2804 __func__);
2805 continue;
2806 }
2807 nrt = (rectype_t)now;
2808 if (nrt == REC_NONE)
2809 nrt = (rectype_t)(~mode & REC_FULL);
2810 if (schanged++ == 0) {
2811 crt = nrt;
2812 } else if (crt != nrt)
2813 continue;
2814 if (!m_append(m, sizeof(struct in6_addr),
2815 (void *)&ims->im6s_addr)) {
2816 if (m != m0)
2817 m_freem(m);
2818 CTR1(KTR_MLD,
2819 "%s: m_append() failed", __func__);
2820 return (-ENOMEM);
2821 }
2822 nallow += !!(crt == REC_ALLOW);
2823 nblock += !!(crt == REC_BLOCK);
2824 if (++rsrcs == m0srcs)
2825 break;
2826 }
2827 /*
2828 * If we did not append any tree nodes on this
2829 * pass, back out of allocations.
2830 */
2831 if (rsrcs == 0) {
2832 npbytes -= sizeof(struct mldv2_record);
2833 if (m != m0) {
2834 CTR1(KTR_MLD,
2835 "%s: m_free(m)", __func__);
2836 m_freem(m);
2837 } else {
2838 CTR1(KTR_MLD,
2839 "%s: m_adj(m, -mr)", __func__);
2840 m_adj(m, -((int)sizeof(
2841 struct mldv2_record)));
2842 }
2843 continue;
2844 }
2845 npbytes += (rsrcs * sizeof(struct in6_addr));
2846 if (crt == REC_ALLOW)
2847 pmr->mr_type = MLD_ALLOW_NEW_SOURCES;
2848 else if (crt == REC_BLOCK)
2849 pmr->mr_type = MLD_BLOCK_OLD_SOURCES;
2850 pmr->mr_numsrc = htons(rsrcs);
2851 /*
2852 * Count the new group record, and enqueue this
2853 * packet if it wasn't already queued.
2854 */
2855 m->m_pkthdr.PH_vt.vt_nrecs++;
2856 if (m != m0)
2857 _IF_ENQUEUE(ifq, m);
2858 nbytes += npbytes;
2859 } while (nims != NULL);
2860 drt |= crt;
2861 crt = (~crt & REC_FULL);
2862 }
2863
2864 CTR3(KTR_MLD, "%s: queued %d ALLOW_NEW, %d BLOCK_OLD", __func__,
2865 nallow, nblock);
2866
2867 return (nbytes);
2868 }
2869
2870 static int
2871 mld_v2_merge_state_changes(struct in6_multi *inm, struct ifqueue *ifscq)
2872 {
2873 struct ifqueue *gq;
2874 struct mbuf *m; /* pending state-change */
2875 struct mbuf *m0; /* copy of pending state-change */
2876 struct mbuf *mt; /* last state-change in packet */
2877 int docopy, domerge;
2878 u_int recslen;
2879
2880 docopy = 0;
2881 domerge = 0;
2882 recslen = 0;
2883
2884 IN6_MULTI_LOCK_ASSERT();
2885 MLD_LOCK_ASSERT();
2886
2887 /*
2888 * If there are further pending retransmissions, make a writable
2889 * copy of each queued state-change message before merging.
2890 */
2891 if (inm->in6m_scrv > 0)
2892 docopy = 1;
2893
2894 gq = &inm->in6m_scq;
2895 #ifdef KTR
2896 if (gq->ifq_head == NULL) {
2897 CTR2(KTR_MLD, "%s: WARNING: queue for inm %p is empty",
2898 __func__, inm);
2899 }
2900 #endif
2901
2902 m = gq->ifq_head;
2903 while (m != NULL) {
2904 /*
2905 * Only merge the report into the current packet if
2906 * there is sufficient space to do so; an MLDv2 report
2907 * packet may only contain 65,535 group records.
2908 * Always use a simple mbuf chain concatentation to do this,
2909 * as large state changes for single groups may have
2910 * allocated clusters.
2911 */
2912 domerge = 0;
2913 mt = ifscq->ifq_tail;
2914 if (mt != NULL) {
2915 recslen = m_length(m, NULL);
2916
2917 if ((mt->m_pkthdr.PH_vt.vt_nrecs +
2918 m->m_pkthdr.PH_vt.vt_nrecs <=
2919 MLD_V2_REPORT_MAXRECS) &&
2920 (mt->m_pkthdr.len + recslen <=
2921 (inm->in6m_ifp->if_mtu - MLD_MTUSPACE)))
2922 domerge = 1;
2923 }
2924
2925 if (!domerge && _IF_QFULL(gq)) {
2926 CTR2(KTR_MLD,
2927 "%s: outbound queue full, skipping whole packet %p",
2928 __func__, m);
2929 mt = m->m_nextpkt;
2930 if (!docopy)
2931 m_freem(m);
2932 m = mt;
2933 continue;
2934 }
2935
2936 if (!docopy) {
2937 CTR2(KTR_MLD, "%s: dequeueing %p", __func__, m);
2938 _IF_DEQUEUE(gq, m0);
2939 m = m0->m_nextpkt;
2940 } else {
2941 CTR2(KTR_MLD, "%s: copying %p", __func__, m);
2942 m0 = m_dup(m, M_NOWAIT);
2943 if (m0 == NULL)
2944 return (ENOMEM);
2945 m0->m_nextpkt = NULL;
2946 m = m->m_nextpkt;
2947 }
2948
2949 if (!domerge) {
2950 CTR3(KTR_MLD, "%s: queueing %p to ifscq %p)",
2951 __func__, m0, ifscq);
2952 _IF_ENQUEUE(ifscq, m0);
2953 } else {
2954 struct mbuf *mtl; /* last mbuf of packet mt */
2955
2956 CTR3(KTR_MLD, "%s: merging %p with ifscq tail %p)",
2957 __func__, m0, mt);
2958
2959 mtl = m_last(mt);
2960 m0->m_flags &= ~M_PKTHDR;
2961 mt->m_pkthdr.len += recslen;
2962 mt->m_pkthdr.PH_vt.vt_nrecs +=
2963 m0->m_pkthdr.PH_vt.vt_nrecs;
2964
2965 mtl->m_next = m0;
2966 }
2967 }
2968
2969 return (0);
2970 }
2971
2972 /*
2973 * Respond to a pending MLDv2 General Query.
2974 */
2975 static void
2976 mld_v2_dispatch_general_query(struct mld_ifinfo *mli)
2977 {
2978 struct ifmultiaddr *ifma, *tifma;
2979 struct ifnet *ifp;
2980 struct in6_multi *inm;
2981 int retval;
2982
2983 IN6_MULTI_LOCK_ASSERT();
2984 MLD_LOCK_ASSERT();
2985
2986 KASSERT(mli->mli_version == MLD_VERSION_2,
2987 ("%s: called when version %d", __func__, mli->mli_version));
2988
2989 ifp = mli->mli_ifp;
2990
2991 IF_ADDR_LOCK(ifp);
2992 TAILQ_FOREACH_SAFE(ifma, &ifp->if_multiaddrs, ifma_link, tifma) {
2993 if (ifma->ifma_addr->sa_family != AF_INET6 ||
2994 ifma->ifma_protospec == NULL)
2995 continue;
2996
2997 inm = (struct in6_multi *)ifma->ifma_protospec;
2998 KASSERT(ifp == inm->in6m_ifp,
2999 ("%s: inconsistent ifp", __func__));
3000
3001 switch (inm->in6m_state) {
3002 case MLD_NOT_MEMBER:
3003 case MLD_SILENT_MEMBER:
3004 break;
3005 case MLD_REPORTING_MEMBER:
3006 case MLD_IDLE_MEMBER:
3007 case MLD_LAZY_MEMBER:
3008 case MLD_SLEEPING_MEMBER:
3009 case MLD_AWAKENING_MEMBER:
3010 inm->in6m_state = MLD_REPORTING_MEMBER;
3011 retval = mld_v2_enqueue_group_record(&mli->mli_gq,
3012 inm, 0, 0, 0, 0);
3013 CTR2(KTR_MLD, "%s: enqueue record = %d",
3014 __func__, retval);
3015 break;
3016 case MLD_G_QUERY_PENDING_MEMBER:
3017 case MLD_SG_QUERY_PENDING_MEMBER:
3018 case MLD_LEAVING_MEMBER:
3019 break;
3020 }
3021 }
3022 IF_ADDR_UNLOCK(ifp);
3023
3024 mld_dispatch_queue(&mli->mli_gq, MLD_MAX_RESPONSE_BURST);
3025
3026 /*
3027 * Slew transmission of bursts over 500ms intervals.
3028 */
3029 if (mli->mli_gq.ifq_head != NULL) {
3030 mli->mli_v2_timer = 1 + MLD_RANDOM_DELAY(
3031 MLD_RESPONSE_BURST_INTERVAL);
3032 V_interface_timers_running6 = 1;
3033 }
3034 }
3035
3036 /*
3037 * Transmit the next pending message in the output queue.
3038 *
3039 * VIMAGE: Needs to store/restore vnet pointer on a per-mbuf-chain basis.
3040 * MRT: Nothing needs to be done, as MLD traffic is always local to
3041 * a link and uses a link-scope multicast address.
3042 */
3043 static void
3044 mld_dispatch_packet(struct mbuf *m)
3045 {
3046 struct ip6_moptions im6o;
3047 struct ifnet *ifp;
3048 struct ifnet *oifp;
3049 struct mbuf *m0;
3050 struct mbuf *md;
3051 struct ip6_hdr *ip6;
3052 struct mld_hdr *mld;
3053 int error;
3054 int off;
3055 int type;
3056 uint32_t ifindex;
3057
3058 CTR2(KTR_MLD, "%s: transmit %p", __func__, m);
3059
3060 /*
3061 * Set VNET image pointer from enqueued mbuf chain
3062 * before doing anything else. Whilst we use interface
3063 * indexes to guard against interface detach, they are
3064 * unique to each VIMAGE and must be retrieved.
3065 */
3066 ifindex = mld_restore_context(m);
3067
3068 /*
3069 * Check if the ifnet still exists. This limits the scope of
3070 * any race in the absence of a global ifp lock for low cost
3071 * (an array lookup).
3072 */
3073 ifp = ifnet_byindex(ifindex);
3074 if (ifp == NULL) {
3075 CTR3(KTR_MLD, "%s: dropped %p as ifindex %u went away.",
3076 __func__, m, ifindex);
3077 m_freem(m);
3078 IP6STAT_INC(ip6s_noroute);
3079 goto out;
3080 }
3081
3082 im6o.im6o_multicast_hlim = 1;
3083 im6o.im6o_multicast_loop = (V_ip6_mrouter != NULL);
3084 im6o.im6o_multicast_ifp = ifp;
3085
3086 if (m->m_flags & M_MLDV1) {
3087 m0 = m;
3088 } else {
3089 m0 = mld_v2_encap_report(ifp, m);
3090 if (m0 == NULL) {
3091 CTR2(KTR_MLD, "%s: dropped %p", __func__, m);
3092 m_freem(m);
3093 IP6STAT_INC(ip6s_odropped);
3094 goto out;
3095 }
3096 }
3097
3098 mld_scrub_context(m0);
3099 m->m_flags &= ~(M_PROTOFLAGS);
3100 m0->m_pkthdr.rcvif = V_loif;
3101
3102 ip6 = mtod(m0, struct ip6_hdr *);
3103 #if 0
3104 (void)in6_setscope(&ip6->ip6_dst, ifp, NULL); /* XXX LOR */
3105 #else
3106 /*
3107 * XXX XXX Break some KPI rules to prevent an LOR which would
3108 * occur if we called in6_setscope() at transmission.
3109 * See comments at top of file.
3110 */
3111 MLD_EMBEDSCOPE(&ip6->ip6_dst, ifp->if_index);
3112 #endif
3113
3114 /*
3115 * Retrieve the ICMPv6 type before handoff to ip6_output(),
3116 * so we can bump the stats.
3117 */
3118 md = m_getptr(m0, sizeof(struct ip6_hdr), &off);
3119 mld = (struct mld_hdr *)(mtod(md, uint8_t *) + off);
3120 type = mld->mld_type;
3121
3122 error = ip6_output(m0, &mld_po, NULL, IPV6_UNSPECSRC, &im6o,
3123 &oifp, NULL);
3124 if (error) {
3125 CTR3(KTR_MLD, "%s: ip6_output(%p) = %d", __func__, m0, error);
3126 goto out;
3127 }
3128 ICMP6STAT_INC(icp6s_outhist[type]);
3129 if (oifp != NULL) {
3130 icmp6_ifstat_inc(oifp, ifs6_out_msg);
3131 switch (type) {
3132 case MLD_LISTENER_REPORT:
3133 case MLDV2_LISTENER_REPORT:
3134 icmp6_ifstat_inc(oifp, ifs6_out_mldreport);
3135 break;
3136 case MLD_LISTENER_DONE:
3137 icmp6_ifstat_inc(oifp, ifs6_out_mlddone);
3138 break;
3139 }
3140 }
3141 out:
3142 return;
3143 }
3144
3145 /*
3146 * Encapsulate an MLDv2 report.
3147 *
3148 * KAME IPv6 requires that hop-by-hop options be passed separately,
3149 * and that the IPv6 header be prepended in a separate mbuf.
3150 *
3151 * Returns a pointer to the new mbuf chain head, or NULL if the
3152 * allocation failed.
3153 */
3154 static struct mbuf *
3155 mld_v2_encap_report(struct ifnet *ifp, struct mbuf *m)
3156 {
3157 struct mbuf *mh;
3158 struct mldv2_report *mld;
3159 struct ip6_hdr *ip6;
3160 struct in6_ifaddr *ia;
3161 int mldreclen;
3162
3163 KASSERT(ifp != NULL, ("%s: null ifp", __func__));
3164 KASSERT((m->m_flags & M_PKTHDR),
3165 ("%s: mbuf chain %p is !M_PKTHDR", __func__, m));
3166
3167 /*
3168 * RFC3590: OK to send as :: or tentative during DAD.
3169 */
3170 ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
3171 if (ia == NULL)
3172 CTR1(KTR_MLD, "%s: warning: ia is NULL", __func__);
3173
3174 MGETHDR(mh, M_DONTWAIT, MT_HEADER);
3175 if (mh == NULL) {
3176 if (ia != NULL)
3177 ifa_free(&ia->ia_ifa);
3178 m_freem(m);
3179 return (NULL);
3180 }
3181 MH_ALIGN(mh, sizeof(struct ip6_hdr) + sizeof(struct mldv2_report));
3182
3183 mldreclen = m_length(m, NULL);
3184 CTR2(KTR_MLD, "%s: mldreclen is %d", __func__, mldreclen);
3185
3186 mh->m_len = sizeof(struct ip6_hdr) + sizeof(struct mldv2_report);
3187 mh->m_pkthdr.len = sizeof(struct ip6_hdr) +
3188 sizeof(struct mldv2_report) + mldreclen;
3189
3190 ip6 = mtod(mh, struct ip6_hdr *);
3191 ip6->ip6_flow = 0;
3192 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
3193 ip6->ip6_vfc |= IPV6_VERSION;
3194 ip6->ip6_nxt = IPPROTO_ICMPV6;
3195 ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any;
3196 if (ia != NULL)
3197 ifa_free(&ia->ia_ifa);
3198 ip6->ip6_dst = in6addr_linklocal_allv2routers;
3199 /* scope ID will be set in netisr */
3200
3201 mld = (struct mldv2_report *)(ip6 + 1);
3202 mld->mld_type = MLDV2_LISTENER_REPORT;
3203 mld->mld_code = 0;
3204 mld->mld_cksum = 0;
3205 mld->mld_v2_reserved = 0;
3206 mld->mld_v2_numrecs = htons(m->m_pkthdr.PH_vt.vt_nrecs);
3207 m->m_pkthdr.PH_vt.vt_nrecs = 0;
3208
3209 mh->m_next = m;
3210 mld->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6,
3211 sizeof(struct ip6_hdr), sizeof(struct mldv2_report) + mldreclen);
3212 return (mh);
3213 }
3214
3215 #ifdef KTR
3216 static char *
3217 mld_rec_type_to_str(const int type)
3218 {
3219
3220 switch (type) {
3221 case MLD_CHANGE_TO_EXCLUDE_MODE:
3222 return "TO_EX";
3223 break;
3224 case MLD_CHANGE_TO_INCLUDE_MODE:
3225 return "TO_IN";
3226 break;
3227 case MLD_MODE_IS_EXCLUDE:
3228 return "MODE_EX";
3229 break;
3230 case MLD_MODE_IS_INCLUDE:
3231 return "MODE_IN";
3232 break;
3233 case MLD_ALLOW_NEW_SOURCES:
3234 return "ALLOW_NEW";
3235 break;
3236 case MLD_BLOCK_OLD_SOURCES:
3237 return "BLOCK_OLD";
3238 break;
3239 default:
3240 break;
3241 }
3242 return "unknown";
3243 }
3244 #endif
3245
3246 static void
3247 mld_init(void *unused __unused)
3248 {
3249
3250 CTR1(KTR_MLD, "%s: initializing", __func__);
3251 MLD_LOCK_INIT();
3252
3253 ip6_initpktopts(&mld_po);
3254 mld_po.ip6po_hlim = 1;
3255 mld_po.ip6po_hbh = &mld_ra.hbh;
3256 mld_po.ip6po_prefer_tempaddr = IP6PO_TEMPADDR_NOTPREFER;
3257 mld_po.ip6po_flags = IP6PO_DONTFRAG;
3258 }
3259 SYSINIT(mld_init, SI_SUB_PSEUDO, SI_ORDER_MIDDLE, mld_init, NULL);
3260
3261 static void
3262 mld_uninit(void *unused __unused)
3263 {
3264
3265 CTR1(KTR_MLD, "%s: tearing down", __func__);
3266 MLD_LOCK_DESTROY();
3267 }
3268 SYSUNINIT(mld_uninit, SI_SUB_PSEUDO, SI_ORDER_MIDDLE, mld_uninit, NULL);
3269
3270 static void
3271 vnet_mld_init(const void *unused __unused)
3272 {
3273
3274 CTR1(KTR_MLD, "%s: initializing", __func__);
3275
3276 LIST_INIT(&V_mli_head);
3277 }
3278 VNET_SYSINIT(vnet_mld_init, SI_SUB_PSEUDO, SI_ORDER_ANY, vnet_mld_init,
3279 NULL);
3280
3281 static void
3282 vnet_mld_uninit(const void *unused __unused)
3283 {
3284
3285 CTR1(KTR_MLD, "%s: tearing down", __func__);
3286
3287 KASSERT(LIST_EMPTY(&V_mli_head),
3288 ("%s: mli list not empty; ifnets not detached?", __func__));
3289 }
3290 VNET_SYSUNINIT(vnet_mld_uninit, SI_SUB_PSEUDO, SI_ORDER_ANY, vnet_mld_uninit,
3291 NULL);
3292
3293 static int
3294 mld_modevent(module_t mod, int type, void *unused __unused)
3295 {
3296
3297 switch (type) {
3298 case MOD_LOAD:
3299 case MOD_UNLOAD:
3300 break;
3301 default:
3302 return (EOPNOTSUPP);
3303 }
3304 return (0);
3305 }
3306
3307 static moduledata_t mld_mod = {
3308 "mld",
3309 mld_modevent,
3310 0
3311 };
3312 DECLARE_MODULE(mld, mld_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
Cache object: 97a95bd525134d4996cf575767505846
|