FreeBSD/Linux Kernel Cross Reference
sys/netinet6/mld6.c
1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2009 Bruce Simpson.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote
15 * products derived from this software without specific prior written
16 * permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 * $KAME: mld6.c,v 1.27 2001/04/04 05:17:30 itojun Exp $
31 */
32
33 /*-
34 * Copyright (c) 1988 Stephen Deering.
35 * Copyright (c) 1992, 1993
36 * The Regents of the University of California. All rights reserved.
37 *
38 * This code is derived from software contributed to Berkeley by
39 * Stephen Deering of Stanford University.
40 *
41 * Redistribution and use in source and binary forms, with or without
42 * modification, are permitted provided that the following conditions
43 * are met:
44 * 1. Redistributions of source code must retain the above copyright
45 * notice, this list of conditions and the following disclaimer.
46 * 2. Redistributions in binary form must reproduce the above copyright
47 * notice, this list of conditions and the following disclaimer in the
48 * documentation and/or other materials provided with the distribution.
49 * 3. Neither the name of the University nor the names of its contributors
50 * may be used to endorse or promote products derived from this software
51 * without specific prior written permission.
52 *
53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63 * SUCH DAMAGE.
64 *
65 * @(#)igmp.c 8.1 (Berkeley) 7/19/93
66 */
67
68 #include <sys/cdefs.h>
69 __FBSDID("$FreeBSD: releng/12.0/sys/netinet6/mld6.c 338163 2018-08-21 23:03:02Z mmacy $");
70
71 #include "opt_inet.h"
72 #include "opt_inet6.h"
73
74 #include <sys/param.h>
75 #include <sys/systm.h>
76 #include <sys/mbuf.h>
77 #include <sys/socket.h>
78 #include <sys/protosw.h>
79 #include <sys/sysctl.h>
80 #include <sys/kernel.h>
81 #include <sys/callout.h>
82 #include <sys/malloc.h>
83 #include <sys/module.h>
84 #include <sys/ktr.h>
85
86 #include <net/if.h>
87 #include <net/if_var.h>
88 #include <net/route.h>
89 #include <net/vnet.h>
90
91 #include <netinet/in.h>
92 #include <netinet/in_var.h>
93 #include <netinet6/in6_var.h>
94 #include <netinet/ip6.h>
95 #include <netinet6/ip6_var.h>
96 #include <netinet6/scope6_var.h>
97 #include <netinet/icmp6.h>
98 #include <netinet6/mld6.h>
99 #include <netinet6/mld6_var.h>
100
101 #include <security/mac/mac_framework.h>
102
103 #ifndef KTR_MLD
104 #define KTR_MLD KTR_INET6
105 #endif
106
107 static struct mld_ifsoftc *
108 mli_alloc_locked(struct ifnet *);
109 static void mli_delete_locked(const struct ifnet *);
110 static void mld_dispatch_packet(struct mbuf *);
111 static void mld_dispatch_queue(struct mbufq *, int);
112 static void mld_final_leave(struct in6_multi *, struct mld_ifsoftc *);
113 static void mld_fasttimo_vnet(void);
114 static int mld_handle_state_change(struct in6_multi *,
115 struct mld_ifsoftc *);
116 static int mld_initial_join(struct in6_multi *, struct mld_ifsoftc *,
117 const int);
118 #ifdef KTR
119 static char * mld_rec_type_to_str(const int);
120 #endif
121 static void mld_set_version(struct mld_ifsoftc *, const int);
122 static void mld_slowtimo_vnet(void);
123 static int mld_v1_input_query(struct ifnet *, const struct ip6_hdr *,
124 /*const*/ struct mld_hdr *);
125 static int mld_v1_input_report(struct ifnet *, const struct ip6_hdr *,
126 /*const*/ struct mld_hdr *);
127 static void mld_v1_process_group_timer(struct in6_multi_head *,
128 struct in6_multi *);
129 static void mld_v1_process_querier_timers(struct mld_ifsoftc *);
130 static int mld_v1_transmit_report(struct in6_multi *, const int);
131 static void mld_v1_update_group(struct in6_multi *, const int);
132 static void mld_v2_cancel_link_timers(struct mld_ifsoftc *);
133 static void mld_v2_dispatch_general_query(struct mld_ifsoftc *);
134 static struct mbuf *
135 mld_v2_encap_report(struct ifnet *, struct mbuf *);
136 static int mld_v2_enqueue_filter_change(struct mbufq *,
137 struct in6_multi *);
138 static int mld_v2_enqueue_group_record(struct mbufq *,
139 struct in6_multi *, const int, const int, const int,
140 const int);
141 static int mld_v2_input_query(struct ifnet *, const struct ip6_hdr *,
142 struct mbuf *, const int, const int);
143 static int mld_v2_merge_state_changes(struct in6_multi *,
144 struct mbufq *);
145 static void mld_v2_process_group_timers(struct in6_multi_head *,
146 struct mbufq *, struct mbufq *,
147 struct in6_multi *, const int);
148 static int mld_v2_process_group_query(struct in6_multi *,
149 struct mld_ifsoftc *mli, int, struct mbuf *, const int);
150 static int sysctl_mld_gsr(SYSCTL_HANDLER_ARGS);
151 static int sysctl_mld_ifinfo(SYSCTL_HANDLER_ARGS);
152
153 /*
154 * Normative references: RFC 2710, RFC 3590, RFC 3810.
155 *
156 * Locking:
157 * * The MLD subsystem lock ends up being system-wide for the moment,
158 * but could be per-VIMAGE later on.
159 * * The permitted lock order is: IN6_MULTI_LOCK, MLD_LOCK, IF_ADDR_LOCK.
160 * Any may be taken independently; if any are held at the same
161 * time, the above lock order must be followed.
162 * * IN6_MULTI_LOCK covers in_multi.
163 * * MLD_LOCK covers per-link state and any global variables in this file.
164 * * IF_ADDR_LOCK covers if_multiaddrs, which is used for a variety of
165 * per-link state iterators.
166 *
167 * XXX LOR PREVENTION
168 * A special case for IPv6 is the in6_setscope() routine. ip6_output()
169 * will not accept an ifp; it wants an embedded scope ID, unlike
170 * ip_output(), which happily takes the ifp given to it. The embedded
171 * scope ID is only used by MLD to select the outgoing interface.
172 *
173 * During interface attach and detach, MLD will take MLD_LOCK *after*
174 * the IF_AFDATA_LOCK.
175 * As in6_setscope() takes IF_AFDATA_LOCK then SCOPE_LOCK, we can't call
176 * it with MLD_LOCK held without triggering an LOR. A netisr with indirect
177 * dispatch could work around this, but we'd rather not do that, as it
178 * can introduce other races.
179 *
180 * As such, we exploit the fact that the scope ID is just the interface
181 * index, and embed it in the IPv6 destination address accordingly.
182 * This is potentially NOT VALID for MLDv1 reports, as they
183 * are always sent to the multicast group itself; as MLDv2
184 * reports are always sent to ff02::16, this is not an issue
185 * when MLDv2 is in use.
186 *
187 * This does not however eliminate the LOR when ip6_output() itself
188 * calls in6_setscope() internally whilst MLD_LOCK is held. This will
189 * trigger a LOR warning in WITNESS when the ifnet is detached.
190 *
191 * The right answer is probably to make IF_AFDATA_LOCK an rwlock, given
192 * how it's used across the network stack. Here we're simply exploiting
193 * the fact that MLD runs at a similar layer in the stack to scope6.c.
194 *
195 * VIMAGE:
196 * * Each in6_multi corresponds to an ifp, and each ifp corresponds
197 * to a vnet in ifp->if_vnet.
198 */
199 static struct mtx mld_mtx;
200 static MALLOC_DEFINE(M_MLD, "mld", "mld state");
201
202 #define MLD_EMBEDSCOPE(pin6, zoneid) \
203 if (IN6_IS_SCOPE_LINKLOCAL(pin6) || \
204 IN6_IS_ADDR_MC_INTFACELOCAL(pin6)) \
205 (pin6)->s6_addr16[1] = htons((zoneid) & 0xFFFF) \
206
207 /*
208 * VIMAGE-wide globals.
209 */
210 VNET_DEFINE_STATIC(struct timeval, mld_gsrdelay) = {10, 0};
211 VNET_DEFINE_STATIC(LIST_HEAD(, mld_ifsoftc), mli_head);
212 VNET_DEFINE_STATIC(int, interface_timers_running6);
213 VNET_DEFINE_STATIC(int, state_change_timers_running6);
214 VNET_DEFINE_STATIC(int, current_state_timers_running6);
215
216 #define V_mld_gsrdelay VNET(mld_gsrdelay)
217 #define V_mli_head VNET(mli_head)
218 #define V_interface_timers_running6 VNET(interface_timers_running6)
219 #define V_state_change_timers_running6 VNET(state_change_timers_running6)
220 #define V_current_state_timers_running6 VNET(current_state_timers_running6)
221
222 SYSCTL_DECL(_net_inet6); /* Note: Not in any common header. */
223
224 SYSCTL_NODE(_net_inet6, OID_AUTO, mld, CTLFLAG_RW, 0,
225 "IPv6 Multicast Listener Discovery");
226
227 /*
228 * Virtualized sysctls.
229 */
230 SYSCTL_PROC(_net_inet6_mld, OID_AUTO, gsrdelay,
231 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
232 &VNET_NAME(mld_gsrdelay.tv_sec), 0, sysctl_mld_gsr, "I",
233 "Rate limit for MLDv2 Group-and-Source queries in seconds");
234
235 /*
236 * Non-virtualized sysctls.
237 */
238 static SYSCTL_NODE(_net_inet6_mld, OID_AUTO, ifinfo,
239 CTLFLAG_RD | CTLFLAG_MPSAFE, sysctl_mld_ifinfo,
240 "Per-interface MLDv2 state");
241
242 static int mld_v1enable = 1;
243 SYSCTL_INT(_net_inet6_mld, OID_AUTO, v1enable, CTLFLAG_RWTUN,
244 &mld_v1enable, 0, "Enable fallback to MLDv1");
245
246 static int mld_use_allow = 1;
247 SYSCTL_INT(_net_inet6_mld, OID_AUTO, use_allow, CTLFLAG_RWTUN,
248 &mld_use_allow, 0, "Use ALLOW/BLOCK for RFC 4604 SSM joins/leaves");
249
250 /*
251 * Packed Router Alert option structure declaration.
252 */
253 struct mld_raopt {
254 struct ip6_hbh hbh;
255 struct ip6_opt pad;
256 struct ip6_opt_router ra;
257 } __packed;
258
259 /*
260 * Router Alert hop-by-hop option header.
261 */
262 static struct mld_raopt mld_ra = {
263 .hbh = { 0, 0 },
264 .pad = { .ip6o_type = IP6OPT_PADN, 0 },
265 .ra = {
266 .ip6or_type = IP6OPT_ROUTER_ALERT,
267 .ip6or_len = IP6OPT_RTALERT_LEN - 2,
268 .ip6or_value[0] = ((IP6OPT_RTALERT_MLD >> 8) & 0xFF),
269 .ip6or_value[1] = (IP6OPT_RTALERT_MLD & 0xFF)
270 }
271 };
272 static struct ip6_pktopts mld_po;
273
274 static __inline void
275 mld_save_context(struct mbuf *m, struct ifnet *ifp)
276 {
277
278 #ifdef VIMAGE
279 m->m_pkthdr.PH_loc.ptr = ifp->if_vnet;
280 #endif /* VIMAGE */
281 m->m_pkthdr.flowid = ifp->if_index;
282 }
283
284 static __inline void
285 mld_scrub_context(struct mbuf *m)
286 {
287
288 m->m_pkthdr.PH_loc.ptr = NULL;
289 m->m_pkthdr.flowid = 0;
290 }
291
292 /*
293 * Restore context from a queued output chain.
294 * Return saved ifindex.
295 *
296 * VIMAGE: The assertion is there to make sure that we
297 * actually called CURVNET_SET() with what's in the mbuf chain.
298 */
299 static __inline uint32_t
300 mld_restore_context(struct mbuf *m)
301 {
302
303 #if defined(VIMAGE) && defined(INVARIANTS)
304 KASSERT(curvnet == m->m_pkthdr.PH_loc.ptr,
305 ("%s: called when curvnet was not restored: cuvnet %p m ptr %p",
306 __func__, curvnet, m->m_pkthdr.PH_loc.ptr));
307 #endif
308 return (m->m_pkthdr.flowid);
309 }
310
311 /*
312 * Retrieve or set threshold between group-source queries in seconds.
313 *
314 * VIMAGE: Assume curvnet set by caller.
315 * SMPng: NOTE: Serialized by MLD lock.
316 */
317 static int
318 sysctl_mld_gsr(SYSCTL_HANDLER_ARGS)
319 {
320 int error;
321 int i;
322
323 error = sysctl_wire_old_buffer(req, sizeof(int));
324 if (error)
325 return (error);
326
327 MLD_LOCK();
328
329 i = V_mld_gsrdelay.tv_sec;
330
331 error = sysctl_handle_int(oidp, &i, 0, req);
332 if (error || !req->newptr)
333 goto out_locked;
334
335 if (i < -1 || i >= 60) {
336 error = EINVAL;
337 goto out_locked;
338 }
339
340 CTR2(KTR_MLD, "change mld_gsrdelay from %d to %d",
341 V_mld_gsrdelay.tv_sec, i);
342 V_mld_gsrdelay.tv_sec = i;
343
344 out_locked:
345 MLD_UNLOCK();
346 return (error);
347 }
348
349 /*
350 * Expose struct mld_ifsoftc to userland, keyed by ifindex.
351 * For use by ifmcstat(8).
352 *
353 * SMPng: NOTE: Does an unlocked ifindex space read.
354 * VIMAGE: Assume curvnet set by caller. The node handler itself
355 * is not directly virtualized.
356 */
357 static int
358 sysctl_mld_ifinfo(SYSCTL_HANDLER_ARGS)
359 {
360 int *name;
361 int error;
362 u_int namelen;
363 struct ifnet *ifp;
364 struct mld_ifsoftc *mli;
365
366 name = (int *)arg1;
367 namelen = arg2;
368
369 if (req->newptr != NULL)
370 return (EPERM);
371
372 if (namelen != 1)
373 return (EINVAL);
374
375 error = sysctl_wire_old_buffer(req, sizeof(struct mld_ifinfo));
376 if (error)
377 return (error);
378
379 IN6_MULTI_LOCK();
380 IN6_MULTI_LIST_LOCK();
381 MLD_LOCK();
382
383 if (name[0] <= 0 || name[0] > V_if_index) {
384 error = ENOENT;
385 goto out_locked;
386 }
387
388 error = ENOENT;
389
390 ifp = ifnet_byindex(name[0]);
391 if (ifp == NULL)
392 goto out_locked;
393
394 LIST_FOREACH(mli, &V_mli_head, mli_link) {
395 if (ifp == mli->mli_ifp) {
396 struct mld_ifinfo info;
397
398 info.mli_version = mli->mli_version;
399 info.mli_v1_timer = mli->mli_v1_timer;
400 info.mli_v2_timer = mli->mli_v2_timer;
401 info.mli_flags = mli->mli_flags;
402 info.mli_rv = mli->mli_rv;
403 info.mli_qi = mli->mli_qi;
404 info.mli_qri = mli->mli_qri;
405 info.mli_uri = mli->mli_uri;
406 error = SYSCTL_OUT(req, &info, sizeof(info));
407 break;
408 }
409 }
410
411 out_locked:
412 MLD_UNLOCK();
413 IN6_MULTI_LIST_UNLOCK();
414 IN6_MULTI_UNLOCK();
415 return (error);
416 }
417
418 /*
419 * Dispatch an entire queue of pending packet chains.
420 * VIMAGE: Assumes the vnet pointer has been set.
421 */
422 static void
423 mld_dispatch_queue(struct mbufq *mq, int limit)
424 {
425 struct mbuf *m;
426
427 while ((m = mbufq_dequeue(mq)) != NULL) {
428 CTR3(KTR_MLD, "%s: dispatch %p from %p", __func__, mq, m);
429 mld_dispatch_packet(m);
430 if (--limit == 0)
431 break;
432 }
433 }
434
435 /*
436 * Filter outgoing MLD report state by group.
437 *
438 * Reports are ALWAYS suppressed for ALL-HOSTS (ff02::1)
439 * and node-local addresses. However, kernel and socket consumers
440 * always embed the KAME scope ID in the address provided, so strip it
441 * when performing comparison.
442 * Note: This is not the same as the *multicast* scope.
443 *
444 * Return zero if the given group is one for which MLD reports
445 * should be suppressed, or non-zero if reports should be issued.
446 */
447 static __inline int
448 mld_is_addr_reported(const struct in6_addr *addr)
449 {
450
451 KASSERT(IN6_IS_ADDR_MULTICAST(addr), ("%s: not multicast", __func__));
452
453 if (IPV6_ADDR_MC_SCOPE(addr) == IPV6_ADDR_SCOPE_NODELOCAL)
454 return (0);
455
456 if (IPV6_ADDR_MC_SCOPE(addr) == IPV6_ADDR_SCOPE_LINKLOCAL) {
457 struct in6_addr tmp = *addr;
458 in6_clearscope(&tmp);
459 if (IN6_ARE_ADDR_EQUAL(&tmp, &in6addr_linklocal_allnodes))
460 return (0);
461 }
462
463 return (1);
464 }
465
466 /*
467 * Attach MLD when PF_INET6 is attached to an interface.
468 *
469 * SMPng: Normally called with IF_AFDATA_LOCK held.
470 */
471 struct mld_ifsoftc *
472 mld_domifattach(struct ifnet *ifp)
473 {
474 struct mld_ifsoftc *mli;
475
476 CTR3(KTR_MLD, "%s: called for ifp %p(%s)",
477 __func__, ifp, if_name(ifp));
478
479 MLD_LOCK();
480
481 mli = mli_alloc_locked(ifp);
482 if (!(ifp->if_flags & IFF_MULTICAST))
483 mli->mli_flags |= MLIF_SILENT;
484 if (mld_use_allow)
485 mli->mli_flags |= MLIF_USEALLOW;
486
487 MLD_UNLOCK();
488
489 return (mli);
490 }
491
492 /*
493 * VIMAGE: assume curvnet set by caller.
494 */
495 static struct mld_ifsoftc *
496 mli_alloc_locked(/*const*/ struct ifnet *ifp)
497 {
498 struct mld_ifsoftc *mli;
499
500 MLD_LOCK_ASSERT();
501
502 mli = malloc(sizeof(struct mld_ifsoftc), M_MLD, M_NOWAIT|M_ZERO);
503 if (mli == NULL)
504 goto out;
505
506 mli->mli_ifp = ifp;
507 mli->mli_version = MLD_VERSION_2;
508 mli->mli_flags = 0;
509 mli->mli_rv = MLD_RV_INIT;
510 mli->mli_qi = MLD_QI_INIT;
511 mli->mli_qri = MLD_QRI_INIT;
512 mli->mli_uri = MLD_URI_INIT;
513 mbufq_init(&mli->mli_gq, MLD_MAX_RESPONSE_PACKETS);
514
515 LIST_INSERT_HEAD(&V_mli_head, mli, mli_link);
516
517 CTR2(KTR_MLD, "allocate mld_ifsoftc for ifp %p(%s)",
518 ifp, if_name(ifp));
519
520 out:
521 return (mli);
522 }
523
524 /*
525 * Hook for ifdetach.
526 *
527 * NOTE: Some finalization tasks need to run before the protocol domain
528 * is detached, but also before the link layer does its cleanup.
529 * Run before link-layer cleanup; cleanup groups, but do not free MLD state.
530 *
531 * SMPng: Caller must hold IN6_MULTI_LOCK().
532 * Must take IF_ADDR_LOCK() to cover if_multiaddrs iterator.
533 * XXX This routine is also bitten by unlocked ifma_protospec access.
534 */
535 void
536 mld_ifdetach(struct ifnet *ifp)
537 {
538 struct mld_ifsoftc *mli;
539 struct ifmultiaddr *ifma, *next;
540 struct in6_multi *inm;
541 struct in6_multi_head inmh;
542
543 CTR3(KTR_MLD, "%s: called for ifp %p(%s)", __func__, ifp,
544 if_name(ifp));
545
546 SLIST_INIT(&inmh);
547 IN6_MULTI_LIST_LOCK_ASSERT();
548 MLD_LOCK();
549
550 mli = MLD_IFINFO(ifp);
551 if (mli->mli_version == MLD_VERSION_2) {
552 IF_ADDR_WLOCK(ifp);
553 restart:
554 CK_STAILQ_FOREACH_SAFE(ifma, &ifp->if_multiaddrs, ifma_link, next) {
555 if (ifma->ifma_addr->sa_family != AF_INET6 ||
556 ifma->ifma_protospec == NULL)
557 continue;
558 inm = (struct in6_multi *)ifma->ifma_protospec;
559 if (inm->in6m_state == MLD_LEAVING_MEMBER) {
560 in6m_disconnect(inm);
561 in6m_rele_locked(&inmh, inm);
562 ifma->ifma_protospec = NULL;
563 }
564 in6m_clear_recorded(inm);
565 if (__predict_false(ifma6_restart)) {
566 ifma6_restart = false;
567 goto restart;
568 }
569 }
570 IF_ADDR_WUNLOCK(ifp);
571 }
572
573 MLD_UNLOCK();
574 in6m_release_list_deferred(&inmh);
575 }
576
577 /*
578 * Hook for domifdetach.
579 * Runs after link-layer cleanup; free MLD state.
580 *
581 * SMPng: Normally called with IF_AFDATA_LOCK held.
582 */
583 void
584 mld_domifdetach(struct ifnet *ifp)
585 {
586
587 CTR3(KTR_MLD, "%s: called for ifp %p(%s)",
588 __func__, ifp, if_name(ifp));
589
590 MLD_LOCK();
591 mli_delete_locked(ifp);
592 MLD_UNLOCK();
593 }
594
595 static void
596 mli_delete_locked(const struct ifnet *ifp)
597 {
598 struct mld_ifsoftc *mli, *tmli;
599
600 CTR3(KTR_MLD, "%s: freeing mld_ifsoftc for ifp %p(%s)",
601 __func__, ifp, if_name(ifp));
602
603 MLD_LOCK_ASSERT();
604
605 LIST_FOREACH_SAFE(mli, &V_mli_head, mli_link, tmli) {
606 if (mli->mli_ifp == ifp) {
607 /*
608 * Free deferred General Query responses.
609 */
610 mbufq_drain(&mli->mli_gq);
611
612 LIST_REMOVE(mli, mli_link);
613
614 free(mli, M_MLD);
615 return;
616 }
617 }
618 }
619
620 /*
621 * Process a received MLDv1 general or address-specific query.
622 * Assumes that the query header has been pulled up to sizeof(mld_hdr).
623 *
624 * NOTE: Can't be fully const correct as we temporarily embed scope ID in
625 * mld_addr. This is OK as we own the mbuf chain.
626 */
627 static int
628 mld_v1_input_query(struct ifnet *ifp, const struct ip6_hdr *ip6,
629 /*const*/ struct mld_hdr *mld)
630 {
631 struct ifmultiaddr *ifma;
632 struct mld_ifsoftc *mli;
633 struct in6_multi *inm;
634 int is_general_query;
635 uint16_t timer;
636 #ifdef KTR
637 char ip6tbuf[INET6_ADDRSTRLEN];
638 #endif
639
640 is_general_query = 0;
641
642 if (!mld_v1enable) {
643 CTR3(KTR_MLD, "ignore v1 query %s on ifp %p(%s)",
644 ip6_sprintf(ip6tbuf, &mld->mld_addr),
645 ifp, if_name(ifp));
646 return (0);
647 }
648
649 /*
650 * RFC3810 Section 6.2: MLD queries must originate from
651 * a router's link-local address.
652 */
653 if (!IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
654 CTR3(KTR_MLD, "ignore v1 query src %s on ifp %p(%s)",
655 ip6_sprintf(ip6tbuf, &ip6->ip6_src),
656 ifp, if_name(ifp));
657 return (0);
658 }
659
660 /*
661 * Do address field validation upfront before we accept
662 * the query.
663 */
664 if (IN6_IS_ADDR_UNSPECIFIED(&mld->mld_addr)) {
665 /*
666 * MLDv1 General Query.
667 * If this was not sent to the all-nodes group, ignore it.
668 */
669 struct in6_addr dst;
670
671 dst = ip6->ip6_dst;
672 in6_clearscope(&dst);
673 if (!IN6_ARE_ADDR_EQUAL(&dst, &in6addr_linklocal_allnodes))
674 return (EINVAL);
675 is_general_query = 1;
676 } else {
677 /*
678 * Embed scope ID of receiving interface in MLD query for
679 * lookup whilst we don't hold other locks.
680 */
681 in6_setscope(&mld->mld_addr, ifp, NULL);
682 }
683
684 IN6_MULTI_LIST_LOCK();
685 MLD_LOCK();
686
687 /*
688 * Switch to MLDv1 host compatibility mode.
689 */
690 mli = MLD_IFINFO(ifp);
691 KASSERT(mli != NULL, ("%s: no mld_ifsoftc for ifp %p", __func__, ifp));
692 mld_set_version(mli, MLD_VERSION_1);
693
694 timer = (ntohs(mld->mld_maxdelay) * PR_FASTHZ) / MLD_TIMER_SCALE;
695 if (timer == 0)
696 timer = 1;
697
698 IF_ADDR_RLOCK(ifp);
699 if (is_general_query) {
700 /*
701 * For each reporting group joined on this
702 * interface, kick the report timer.
703 */
704 CTR2(KTR_MLD, "process v1 general query on ifp %p(%s)",
705 ifp, if_name(ifp));
706 CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
707 if (ifma->ifma_addr->sa_family != AF_INET6 ||
708 ifma->ifma_protospec == NULL)
709 continue;
710 inm = (struct in6_multi *)ifma->ifma_protospec;
711 mld_v1_update_group(inm, timer);
712 }
713 } else {
714 /*
715 * MLDv1 Group-Specific Query.
716 * If this is a group-specific MLDv1 query, we need only
717 * look up the single group to process it.
718 */
719 inm = in6m_lookup_locked(ifp, &mld->mld_addr);
720 if (inm != NULL) {
721 CTR3(KTR_MLD, "process v1 query %s on ifp %p(%s)",
722 ip6_sprintf(ip6tbuf, &mld->mld_addr),
723 ifp, if_name(ifp));
724 mld_v1_update_group(inm, timer);
725 }
726 /* XXX Clear embedded scope ID as userland won't expect it. */
727 in6_clearscope(&mld->mld_addr);
728 }
729
730 IF_ADDR_RUNLOCK(ifp);
731 MLD_UNLOCK();
732 IN6_MULTI_LIST_UNLOCK();
733
734 return (0);
735 }
736
737 /*
738 * Update the report timer on a group in response to an MLDv1 query.
739 *
740 * If we are becoming the reporting member for this group, start the timer.
741 * If we already are the reporting member for this group, and timer is
742 * below the threshold, reset it.
743 *
744 * We may be updating the group for the first time since we switched
745 * to MLDv2. If we are, then we must clear any recorded source lists,
746 * and transition to REPORTING state; the group timer is overloaded
747 * for group and group-source query responses.
748 *
749 * Unlike MLDv2, the delay per group should be jittered
750 * to avoid bursts of MLDv1 reports.
751 */
752 static void
753 mld_v1_update_group(struct in6_multi *inm, const int timer)
754 {
755 #ifdef KTR
756 char ip6tbuf[INET6_ADDRSTRLEN];
757 #endif
758
759 CTR4(KTR_MLD, "%s: %s/%s timer=%d", __func__,
760 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
761 if_name(inm->in6m_ifp), timer);
762
763 IN6_MULTI_LIST_LOCK_ASSERT();
764
765 switch (inm->in6m_state) {
766 case MLD_NOT_MEMBER:
767 case MLD_SILENT_MEMBER:
768 break;
769 case MLD_REPORTING_MEMBER:
770 if (inm->in6m_timer != 0 &&
771 inm->in6m_timer <= timer) {
772 CTR1(KTR_MLD, "%s: REPORTING and timer running, "
773 "skipping.", __func__);
774 break;
775 }
776 /* FALLTHROUGH */
777 case MLD_SG_QUERY_PENDING_MEMBER:
778 case MLD_G_QUERY_PENDING_MEMBER:
779 case MLD_IDLE_MEMBER:
780 case MLD_LAZY_MEMBER:
781 case MLD_AWAKENING_MEMBER:
782 CTR1(KTR_MLD, "%s: ->REPORTING", __func__);
783 inm->in6m_state = MLD_REPORTING_MEMBER;
784 inm->in6m_timer = MLD_RANDOM_DELAY(timer);
785 V_current_state_timers_running6 = 1;
786 break;
787 case MLD_SLEEPING_MEMBER:
788 CTR1(KTR_MLD, "%s: ->AWAKENING", __func__);
789 inm->in6m_state = MLD_AWAKENING_MEMBER;
790 break;
791 case MLD_LEAVING_MEMBER:
792 break;
793 }
794 }
795
796 /*
797 * Process a received MLDv2 general, group-specific or
798 * group-and-source-specific query.
799 *
800 * Assumes that the query header has been pulled up to sizeof(mldv2_query).
801 *
802 * Return 0 if successful, otherwise an appropriate error code is returned.
803 */
804 static int
805 mld_v2_input_query(struct ifnet *ifp, const struct ip6_hdr *ip6,
806 struct mbuf *m, const int off, const int icmp6len)
807 {
808 struct mld_ifsoftc *mli;
809 struct mldv2_query *mld;
810 struct in6_multi *inm;
811 uint32_t maxdelay, nsrc, qqi;
812 int is_general_query;
813 uint16_t timer;
814 uint8_t qrv;
815 #ifdef KTR
816 char ip6tbuf[INET6_ADDRSTRLEN];
817 #endif
818
819 is_general_query = 0;
820
821 /*
822 * RFC3810 Section 6.2: MLD queries must originate from
823 * a router's link-local address.
824 */
825 if (!IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
826 CTR3(KTR_MLD, "ignore v1 query src %s on ifp %p(%s)",
827 ip6_sprintf(ip6tbuf, &ip6->ip6_src),
828 ifp, if_name(ifp));
829 return (0);
830 }
831
832 CTR2(KTR_MLD, "input v2 query on ifp %p(%s)", ifp, if_name(ifp));
833
834 mld = (struct mldv2_query *)(mtod(m, uint8_t *) + off);
835
836 maxdelay = ntohs(mld->mld_maxdelay); /* in 1/10ths of a second */
837 if (maxdelay >= 32768) {
838 maxdelay = (MLD_MRC_MANT(maxdelay) | 0x1000) <<
839 (MLD_MRC_EXP(maxdelay) + 3);
840 }
841 timer = (maxdelay * PR_FASTHZ) / MLD_TIMER_SCALE;
842 if (timer == 0)
843 timer = 1;
844
845 qrv = MLD_QRV(mld->mld_misc);
846 if (qrv < 2) {
847 CTR3(KTR_MLD, "%s: clamping qrv %d to %d", __func__,
848 qrv, MLD_RV_INIT);
849 qrv = MLD_RV_INIT;
850 }
851
852 qqi = mld->mld_qqi;
853 if (qqi >= 128) {
854 qqi = MLD_QQIC_MANT(mld->mld_qqi) <<
855 (MLD_QQIC_EXP(mld->mld_qqi) + 3);
856 }
857
858 nsrc = ntohs(mld->mld_numsrc);
859 if (nsrc > MLD_MAX_GS_SOURCES)
860 return (EMSGSIZE);
861 if (icmp6len < sizeof(struct mldv2_query) +
862 (nsrc * sizeof(struct in6_addr)))
863 return (EMSGSIZE);
864
865 /*
866 * Do further input validation upfront to avoid resetting timers
867 * should we need to discard this query.
868 */
869 if (IN6_IS_ADDR_UNSPECIFIED(&mld->mld_addr)) {
870 /*
871 * A general query with a source list has undefined
872 * behaviour; discard it.
873 */
874 if (nsrc > 0)
875 return (EINVAL);
876 is_general_query = 1;
877 } else {
878 /*
879 * Embed scope ID of receiving interface in MLD query for
880 * lookup whilst we don't hold other locks (due to KAME
881 * locking lameness). We own this mbuf chain just now.
882 */
883 in6_setscope(&mld->mld_addr, ifp, NULL);
884 }
885
886 IN6_MULTI_LIST_LOCK();
887 MLD_LOCK();
888
889 mli = MLD_IFINFO(ifp);
890 KASSERT(mli != NULL, ("%s: no mld_ifsoftc for ifp %p", __func__, ifp));
891
892 /*
893 * Discard the v2 query if we're in Compatibility Mode.
894 * The RFC is pretty clear that hosts need to stay in MLDv1 mode
895 * until the Old Version Querier Present timer expires.
896 */
897 if (mli->mli_version != MLD_VERSION_2)
898 goto out_locked;
899
900 mld_set_version(mli, MLD_VERSION_2);
901 mli->mli_rv = qrv;
902 mli->mli_qi = qqi;
903 mli->mli_qri = maxdelay;
904
905 CTR4(KTR_MLD, "%s: qrv %d qi %d maxdelay %d", __func__, qrv, qqi,
906 maxdelay);
907
908 if (is_general_query) {
909 /*
910 * MLDv2 General Query.
911 *
912 * Schedule a current-state report on this ifp for
913 * all groups, possibly containing source lists.
914 *
915 * If there is a pending General Query response
916 * scheduled earlier than the selected delay, do
917 * not schedule any other reports.
918 * Otherwise, reset the interface timer.
919 */
920 CTR2(KTR_MLD, "process v2 general query on ifp %p(%s)",
921 ifp, if_name(ifp));
922 if (mli->mli_v2_timer == 0 || mli->mli_v2_timer >= timer) {
923 mli->mli_v2_timer = MLD_RANDOM_DELAY(timer);
924 V_interface_timers_running6 = 1;
925 }
926 } else {
927 /*
928 * MLDv2 Group-specific or Group-and-source-specific Query.
929 *
930 * Group-source-specific queries are throttled on
931 * a per-group basis to defeat denial-of-service attempts.
932 * Queries for groups we are not a member of on this
933 * link are simply ignored.
934 */
935 IF_ADDR_RLOCK(ifp);
936 inm = in6m_lookup_locked(ifp, &mld->mld_addr);
937 if (inm == NULL) {
938 IF_ADDR_RUNLOCK(ifp);
939 goto out_locked;
940 }
941 if (nsrc > 0) {
942 if (!ratecheck(&inm->in6m_lastgsrtv,
943 &V_mld_gsrdelay)) {
944 CTR1(KTR_MLD, "%s: GS query throttled.",
945 __func__);
946 IF_ADDR_RUNLOCK(ifp);
947 goto out_locked;
948 }
949 }
950 CTR2(KTR_MLD, "process v2 group query on ifp %p(%s)",
951 ifp, if_name(ifp));
952 /*
953 * If there is a pending General Query response
954 * scheduled sooner than the selected delay, no
955 * further report need be scheduled.
956 * Otherwise, prepare to respond to the
957 * group-specific or group-and-source query.
958 */
959 if (mli->mli_v2_timer == 0 || mli->mli_v2_timer >= timer)
960 mld_v2_process_group_query(inm, mli, timer, m, off);
961
962 /* XXX Clear embedded scope ID as userland won't expect it. */
963 in6_clearscope(&mld->mld_addr);
964 IF_ADDR_RUNLOCK(ifp);
965 }
966
967 out_locked:
968 MLD_UNLOCK();
969 IN6_MULTI_LIST_UNLOCK();
970
971 return (0);
972 }
973
974 /*
975 * Process a received MLDv2 group-specific or group-and-source-specific
976 * query.
977 * Return <0 if any error occurred. Currently this is ignored.
978 */
979 static int
980 mld_v2_process_group_query(struct in6_multi *inm, struct mld_ifsoftc *mli,
981 int timer, struct mbuf *m0, const int off)
982 {
983 struct mldv2_query *mld;
984 int retval;
985 uint16_t nsrc;
986
987 IN6_MULTI_LIST_LOCK_ASSERT();
988 MLD_LOCK_ASSERT();
989
990 retval = 0;
991 mld = (struct mldv2_query *)(mtod(m0, uint8_t *) + off);
992
993 switch (inm->in6m_state) {
994 case MLD_NOT_MEMBER:
995 case MLD_SILENT_MEMBER:
996 case MLD_SLEEPING_MEMBER:
997 case MLD_LAZY_MEMBER:
998 case MLD_AWAKENING_MEMBER:
999 case MLD_IDLE_MEMBER:
1000 case MLD_LEAVING_MEMBER:
1001 return (retval);
1002 break;
1003 case MLD_REPORTING_MEMBER:
1004 case MLD_G_QUERY_PENDING_MEMBER:
1005 case MLD_SG_QUERY_PENDING_MEMBER:
1006 break;
1007 }
1008
1009 nsrc = ntohs(mld->mld_numsrc);
1010
1011 /*
1012 * Deal with group-specific queries upfront.
1013 * If any group query is already pending, purge any recorded
1014 * source-list state if it exists, and schedule a query response
1015 * for this group-specific query.
1016 */
1017 if (nsrc == 0) {
1018 if (inm->in6m_state == MLD_G_QUERY_PENDING_MEMBER ||
1019 inm->in6m_state == MLD_SG_QUERY_PENDING_MEMBER) {
1020 in6m_clear_recorded(inm);
1021 timer = min(inm->in6m_timer, timer);
1022 }
1023 inm->in6m_state = MLD_G_QUERY_PENDING_MEMBER;
1024 inm->in6m_timer = MLD_RANDOM_DELAY(timer);
1025 V_current_state_timers_running6 = 1;
1026 return (retval);
1027 }
1028
1029 /*
1030 * Deal with the case where a group-and-source-specific query has
1031 * been received but a group-specific query is already pending.
1032 */
1033 if (inm->in6m_state == MLD_G_QUERY_PENDING_MEMBER) {
1034 timer = min(inm->in6m_timer, timer);
1035 inm->in6m_timer = MLD_RANDOM_DELAY(timer);
1036 V_current_state_timers_running6 = 1;
1037 return (retval);
1038 }
1039
1040 /*
1041 * Finally, deal with the case where a group-and-source-specific
1042 * query has been received, where a response to a previous g-s-r
1043 * query exists, or none exists.
1044 * In this case, we need to parse the source-list which the Querier
1045 * has provided us with and check if we have any source list filter
1046 * entries at T1 for these sources. If we do not, there is no need
1047 * schedule a report and the query may be dropped.
1048 * If we do, we must record them and schedule a current-state
1049 * report for those sources.
1050 */
1051 if (inm->in6m_nsrc > 0) {
1052 struct mbuf *m;
1053 uint8_t *sp;
1054 int i, nrecorded;
1055 int soff;
1056
1057 m = m0;
1058 soff = off + sizeof(struct mldv2_query);
1059 nrecorded = 0;
1060 for (i = 0; i < nsrc; i++) {
1061 sp = mtod(m, uint8_t *) + soff;
1062 retval = in6m_record_source(inm,
1063 (const struct in6_addr *)sp);
1064 if (retval < 0)
1065 break;
1066 nrecorded += retval;
1067 soff += sizeof(struct in6_addr);
1068 if (soff >= m->m_len) {
1069 soff = soff - m->m_len;
1070 m = m->m_next;
1071 if (m == NULL)
1072 break;
1073 }
1074 }
1075 if (nrecorded > 0) {
1076 CTR1(KTR_MLD,
1077 "%s: schedule response to SG query", __func__);
1078 inm->in6m_state = MLD_SG_QUERY_PENDING_MEMBER;
1079 inm->in6m_timer = MLD_RANDOM_DELAY(timer);
1080 V_current_state_timers_running6 = 1;
1081 }
1082 }
1083
1084 return (retval);
1085 }
1086
1087 /*
1088 * Process a received MLDv1 host membership report.
1089 * Assumes mld points to mld_hdr in pulled up mbuf chain.
1090 *
1091 * NOTE: Can't be fully const correct as we temporarily embed scope ID in
1092 * mld_addr. This is OK as we own the mbuf chain.
1093 */
1094 static int
1095 mld_v1_input_report(struct ifnet *ifp, const struct ip6_hdr *ip6,
1096 /*const*/ struct mld_hdr *mld)
1097 {
1098 struct in6_addr src, dst;
1099 struct in6_ifaddr *ia;
1100 struct in6_multi *inm;
1101 #ifdef KTR
1102 char ip6tbuf[INET6_ADDRSTRLEN];
1103 #endif
1104
1105 if (!mld_v1enable) {
1106 CTR3(KTR_MLD, "ignore v1 report %s on ifp %p(%s)",
1107 ip6_sprintf(ip6tbuf, &mld->mld_addr),
1108 ifp, if_name(ifp));
1109 return (0);
1110 }
1111
1112 if (ifp->if_flags & IFF_LOOPBACK)
1113 return (0);
1114
1115 /*
1116 * MLDv1 reports must originate from a host's link-local address,
1117 * or the unspecified address (when booting).
1118 */
1119 src = ip6->ip6_src;
1120 in6_clearscope(&src);
1121 if (!IN6_IS_SCOPE_LINKLOCAL(&src) && !IN6_IS_ADDR_UNSPECIFIED(&src)) {
1122 CTR3(KTR_MLD, "ignore v1 query src %s on ifp %p(%s)",
1123 ip6_sprintf(ip6tbuf, &ip6->ip6_src),
1124 ifp, if_name(ifp));
1125 return (EINVAL);
1126 }
1127
1128 /*
1129 * RFC2710 Section 4: MLDv1 reports must pertain to a multicast
1130 * group, and must be directed to the group itself.
1131 */
1132 dst = ip6->ip6_dst;
1133 in6_clearscope(&dst);
1134 if (!IN6_IS_ADDR_MULTICAST(&mld->mld_addr) ||
1135 !IN6_ARE_ADDR_EQUAL(&mld->mld_addr, &dst)) {
1136 CTR3(KTR_MLD, "ignore v1 query dst %s on ifp %p(%s)",
1137 ip6_sprintf(ip6tbuf, &ip6->ip6_dst),
1138 ifp, if_name(ifp));
1139 return (EINVAL);
1140 }
1141
1142 /*
1143 * Make sure we don't hear our own membership report, as fast
1144 * leave requires knowing that we are the only member of a
1145 * group. Assume we used the link-local address if available,
1146 * otherwise look for ::.
1147 *
1148 * XXX Note that scope ID comparison is needed for the address
1149 * returned by in6ifa_ifpforlinklocal(), but SHOULD NOT be
1150 * performed for the on-wire address.
1151 */
1152 ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
1153 if ((ia && IN6_ARE_ADDR_EQUAL(&ip6->ip6_src, IA6_IN6(ia))) ||
1154 (ia == NULL && IN6_IS_ADDR_UNSPECIFIED(&src))) {
1155 if (ia != NULL)
1156 ifa_free(&ia->ia_ifa);
1157 return (0);
1158 }
1159 if (ia != NULL)
1160 ifa_free(&ia->ia_ifa);
1161
1162 CTR3(KTR_MLD, "process v1 report %s on ifp %p(%s)",
1163 ip6_sprintf(ip6tbuf, &mld->mld_addr), ifp, if_name(ifp));
1164
1165 /*
1166 * Embed scope ID of receiving interface in MLD query for lookup
1167 * whilst we don't hold other locks (due to KAME locking lameness).
1168 */
1169 if (!IN6_IS_ADDR_UNSPECIFIED(&mld->mld_addr))
1170 in6_setscope(&mld->mld_addr, ifp, NULL);
1171
1172 IN6_MULTI_LIST_LOCK();
1173 MLD_LOCK();
1174 IF_ADDR_RLOCK(ifp);
1175
1176 /*
1177 * MLDv1 report suppression.
1178 * If we are a member of this group, and our membership should be
1179 * reported, and our group timer is pending or about to be reset,
1180 * stop our group timer by transitioning to the 'lazy' state.
1181 */
1182 inm = in6m_lookup_locked(ifp, &mld->mld_addr);
1183 if (inm != NULL) {
1184 struct mld_ifsoftc *mli;
1185
1186 mli = inm->in6m_mli;
1187 KASSERT(mli != NULL,
1188 ("%s: no mli for ifp %p", __func__, ifp));
1189
1190 /*
1191 * If we are in MLDv2 host mode, do not allow the
1192 * other host's MLDv1 report to suppress our reports.
1193 */
1194 if (mli->mli_version == MLD_VERSION_2)
1195 goto out_locked;
1196
1197 inm->in6m_timer = 0;
1198
1199 switch (inm->in6m_state) {
1200 case MLD_NOT_MEMBER:
1201 case MLD_SILENT_MEMBER:
1202 case MLD_SLEEPING_MEMBER:
1203 break;
1204 case MLD_REPORTING_MEMBER:
1205 case MLD_IDLE_MEMBER:
1206 case MLD_AWAKENING_MEMBER:
1207 CTR3(KTR_MLD,
1208 "report suppressed for %s on ifp %p(%s)",
1209 ip6_sprintf(ip6tbuf, &mld->mld_addr),
1210 ifp, if_name(ifp));
1211 case MLD_LAZY_MEMBER:
1212 inm->in6m_state = MLD_LAZY_MEMBER;
1213 break;
1214 case MLD_G_QUERY_PENDING_MEMBER:
1215 case MLD_SG_QUERY_PENDING_MEMBER:
1216 case MLD_LEAVING_MEMBER:
1217 break;
1218 }
1219 }
1220
1221 out_locked:
1222 IF_ADDR_RUNLOCK(ifp);
1223 MLD_UNLOCK();
1224 IN6_MULTI_LIST_UNLOCK();
1225
1226 /* XXX Clear embedded scope ID as userland won't expect it. */
1227 in6_clearscope(&mld->mld_addr);
1228
1229 return (0);
1230 }
1231
1232 /*
1233 * MLD input path.
1234 *
1235 * Assume query messages which fit in a single ICMPv6 message header
1236 * have been pulled up.
1237 * Assume that userland will want to see the message, even if it
1238 * otherwise fails kernel input validation; do not free it.
1239 * Pullup may however free the mbuf chain m if it fails.
1240 *
1241 * Return IPPROTO_DONE if we freed m. Otherwise, return 0.
1242 */
1243 int
1244 mld_input(struct mbuf *m, int off, int icmp6len)
1245 {
1246 struct ifnet *ifp;
1247 struct ip6_hdr *ip6;
1248 struct mld_hdr *mld;
1249 int mldlen;
1250
1251 CTR3(KTR_MLD, "%s: called w/mbuf (%p,%d)", __func__, m, off);
1252
1253 ifp = m->m_pkthdr.rcvif;
1254
1255 ip6 = mtod(m, struct ip6_hdr *);
1256
1257 /* Pullup to appropriate size. */
1258 mld = (struct mld_hdr *)(mtod(m, uint8_t *) + off);
1259 if (mld->mld_type == MLD_LISTENER_QUERY &&
1260 icmp6len >= sizeof(struct mldv2_query)) {
1261 mldlen = sizeof(struct mldv2_query);
1262 } else {
1263 mldlen = sizeof(struct mld_hdr);
1264 }
1265 IP6_EXTHDR_GET(mld, struct mld_hdr *, m, off, mldlen);
1266 if (mld == NULL) {
1267 ICMP6STAT_INC(icp6s_badlen);
1268 return (IPPROTO_DONE);
1269 }
1270
1271 /*
1272 * Userland needs to see all of this traffic for implementing
1273 * the endpoint discovery portion of multicast routing.
1274 */
1275 switch (mld->mld_type) {
1276 case MLD_LISTENER_QUERY:
1277 icmp6_ifstat_inc(ifp, ifs6_in_mldquery);
1278 if (icmp6len == sizeof(struct mld_hdr)) {
1279 if (mld_v1_input_query(ifp, ip6, mld) != 0)
1280 return (0);
1281 } else if (icmp6len >= sizeof(struct mldv2_query)) {
1282 if (mld_v2_input_query(ifp, ip6, m, off,
1283 icmp6len) != 0)
1284 return (0);
1285 }
1286 break;
1287 case MLD_LISTENER_REPORT:
1288 icmp6_ifstat_inc(ifp, ifs6_in_mldreport);
1289 if (mld_v1_input_report(ifp, ip6, mld) != 0)
1290 return (0);
1291 break;
1292 case MLDV2_LISTENER_REPORT:
1293 icmp6_ifstat_inc(ifp, ifs6_in_mldreport);
1294 break;
1295 case MLD_LISTENER_DONE:
1296 icmp6_ifstat_inc(ifp, ifs6_in_mlddone);
1297 break;
1298 default:
1299 break;
1300 }
1301
1302 return (0);
1303 }
1304
1305 /*
1306 * Fast timeout handler (global).
1307 * VIMAGE: Timeout handlers are expected to service all vimages.
1308 */
1309 void
1310 mld_fasttimo(void)
1311 {
1312 VNET_ITERATOR_DECL(vnet_iter);
1313
1314 VNET_LIST_RLOCK_NOSLEEP();
1315 VNET_FOREACH(vnet_iter) {
1316 CURVNET_SET(vnet_iter);
1317 mld_fasttimo_vnet();
1318 CURVNET_RESTORE();
1319 }
1320 VNET_LIST_RUNLOCK_NOSLEEP();
1321 }
1322
1323 /*
1324 * Fast timeout handler (per-vnet).
1325 *
1326 * VIMAGE: Assume caller has set up our curvnet.
1327 */
1328 static void
1329 mld_fasttimo_vnet(void)
1330 {
1331 struct mbufq scq; /* State-change packets */
1332 struct mbufq qrq; /* Query response packets */
1333 struct ifnet *ifp;
1334 struct mld_ifsoftc *mli;
1335 struct ifmultiaddr *ifma, *next;
1336 struct in6_multi *inm, *tinm;
1337 struct in6_multi_head inmh;
1338 int uri_fasthz;
1339
1340 uri_fasthz = 0;
1341
1342 /*
1343 * Quick check to see if any work needs to be done, in order to
1344 * minimize the overhead of fasttimo processing.
1345 * SMPng: XXX Unlocked reads.
1346 */
1347 if (!V_current_state_timers_running6 &&
1348 !V_interface_timers_running6 &&
1349 !V_state_change_timers_running6)
1350 return;
1351
1352 SLIST_INIT(&inmh);
1353 IN6_MULTI_LIST_LOCK();
1354 MLD_LOCK();
1355
1356 /*
1357 * MLDv2 General Query response timer processing.
1358 */
1359 if (V_interface_timers_running6) {
1360 CTR1(KTR_MLD, "%s: interface timers running", __func__);
1361
1362 V_interface_timers_running6 = 0;
1363 LIST_FOREACH(mli, &V_mli_head, mli_link) {
1364 if (mli->mli_v2_timer == 0) {
1365 /* Do nothing. */
1366 } else if (--mli->mli_v2_timer == 0) {
1367 mld_v2_dispatch_general_query(mli);
1368 } else {
1369 V_interface_timers_running6 = 1;
1370 }
1371 }
1372 }
1373
1374 if (!V_current_state_timers_running6 &&
1375 !V_state_change_timers_running6)
1376 goto out_locked;
1377
1378 V_current_state_timers_running6 = 0;
1379 V_state_change_timers_running6 = 0;
1380
1381 CTR1(KTR_MLD, "%s: state change timers running", __func__);
1382
1383 /*
1384 * MLD host report and state-change timer processing.
1385 * Note: Processing a v2 group timer may remove a node.
1386 */
1387 LIST_FOREACH(mli, &V_mli_head, mli_link) {
1388 ifp = mli->mli_ifp;
1389
1390 if (mli->mli_version == MLD_VERSION_2) {
1391 uri_fasthz = MLD_RANDOM_DELAY(mli->mli_uri *
1392 PR_FASTHZ);
1393 mbufq_init(&qrq, MLD_MAX_G_GS_PACKETS);
1394 mbufq_init(&scq, MLD_MAX_STATE_CHANGE_PACKETS);
1395 }
1396
1397 IF_ADDR_WLOCK(ifp);
1398 restart:
1399 CK_STAILQ_FOREACH_SAFE(ifma, &ifp->if_multiaddrs, ifma_link, next) {
1400 if (ifma->ifma_addr->sa_family != AF_INET6 ||
1401 ifma->ifma_protospec == NULL)
1402 continue;
1403 inm = (struct in6_multi *)ifma->ifma_protospec;
1404 switch (mli->mli_version) {
1405 case MLD_VERSION_1:
1406 mld_v1_process_group_timer(&inmh, inm);
1407 break;
1408 case MLD_VERSION_2:
1409 mld_v2_process_group_timers(&inmh, &qrq,
1410 &scq, inm, uri_fasthz);
1411 break;
1412 }
1413 if (__predict_false(ifma6_restart)) {
1414 ifma6_restart = false;
1415 goto restart;
1416 }
1417 }
1418 IF_ADDR_WUNLOCK(ifp);
1419
1420 switch (mli->mli_version) {
1421 case MLD_VERSION_1:
1422 /*
1423 * Transmit reports for this lifecycle. This
1424 * is done while not holding IF_ADDR_LOCK
1425 * since this can call
1426 * in6ifa_ifpforlinklocal() which locks
1427 * IF_ADDR_LOCK internally as well as
1428 * ip6_output() to transmit a packet.
1429 */
1430 SLIST_FOREACH_SAFE(inm, &inmh, in6m_nrele, tinm) {
1431 SLIST_REMOVE_HEAD(&inmh,
1432 in6m_nrele);
1433 (void)mld_v1_transmit_report(inm,
1434 MLD_LISTENER_REPORT);
1435 }
1436 break;
1437 case MLD_VERSION_2:
1438 mld_dispatch_queue(&qrq, 0);
1439 mld_dispatch_queue(&scq, 0);
1440
1441 /*
1442 * Free the in_multi reference(s) for
1443 * this lifecycle.
1444 */
1445 in6m_release_list_deferred(&inmh);
1446 break;
1447 }
1448 }
1449
1450 out_locked:
1451 MLD_UNLOCK();
1452 IN6_MULTI_LIST_UNLOCK();
1453 }
1454
1455 /*
1456 * Update host report group timer.
1457 * Will update the global pending timer flags.
1458 */
1459 static void
1460 mld_v1_process_group_timer(struct in6_multi_head *inmh, struct in6_multi *inm)
1461 {
1462 int report_timer_expired;
1463
1464 IN6_MULTI_LIST_LOCK_ASSERT();
1465 MLD_LOCK_ASSERT();
1466
1467 if (inm->in6m_timer == 0) {
1468 report_timer_expired = 0;
1469 } else if (--inm->in6m_timer == 0) {
1470 report_timer_expired = 1;
1471 } else {
1472 V_current_state_timers_running6 = 1;
1473 return;
1474 }
1475
1476 switch (inm->in6m_state) {
1477 case MLD_NOT_MEMBER:
1478 case MLD_SILENT_MEMBER:
1479 case MLD_IDLE_MEMBER:
1480 case MLD_LAZY_MEMBER:
1481 case MLD_SLEEPING_MEMBER:
1482 case MLD_AWAKENING_MEMBER:
1483 break;
1484 case MLD_REPORTING_MEMBER:
1485 if (report_timer_expired) {
1486 inm->in6m_state = MLD_IDLE_MEMBER;
1487 in6m_disconnect(inm);
1488 in6m_rele_locked(inmh, inm);
1489 }
1490 break;
1491 case MLD_G_QUERY_PENDING_MEMBER:
1492 case MLD_SG_QUERY_PENDING_MEMBER:
1493 case MLD_LEAVING_MEMBER:
1494 break;
1495 }
1496 }
1497
1498 /*
1499 * Update a group's timers for MLDv2.
1500 * Will update the global pending timer flags.
1501 * Note: Unlocked read from mli.
1502 */
1503 static void
1504 mld_v2_process_group_timers(struct in6_multi_head *inmh,
1505 struct mbufq *qrq, struct mbufq *scq,
1506 struct in6_multi *inm, const int uri_fasthz)
1507 {
1508 int query_response_timer_expired;
1509 int state_change_retransmit_timer_expired;
1510 #ifdef KTR
1511 char ip6tbuf[INET6_ADDRSTRLEN];
1512 #endif
1513
1514 IN6_MULTI_LIST_LOCK_ASSERT();
1515 MLD_LOCK_ASSERT();
1516
1517 query_response_timer_expired = 0;
1518 state_change_retransmit_timer_expired = 0;
1519
1520 /*
1521 * During a transition from compatibility mode back to MLDv2,
1522 * a group record in REPORTING state may still have its group
1523 * timer active. This is a no-op in this function; it is easier
1524 * to deal with it here than to complicate the slow-timeout path.
1525 */
1526 if (inm->in6m_timer == 0) {
1527 query_response_timer_expired = 0;
1528 } else if (--inm->in6m_timer == 0) {
1529 query_response_timer_expired = 1;
1530 } else {
1531 V_current_state_timers_running6 = 1;
1532 }
1533
1534 if (inm->in6m_sctimer == 0) {
1535 state_change_retransmit_timer_expired = 0;
1536 } else if (--inm->in6m_sctimer == 0) {
1537 state_change_retransmit_timer_expired = 1;
1538 } else {
1539 V_state_change_timers_running6 = 1;
1540 }
1541
1542 /* We are in fasttimo, so be quick about it. */
1543 if (!state_change_retransmit_timer_expired &&
1544 !query_response_timer_expired)
1545 return;
1546
1547 switch (inm->in6m_state) {
1548 case MLD_NOT_MEMBER:
1549 case MLD_SILENT_MEMBER:
1550 case MLD_SLEEPING_MEMBER:
1551 case MLD_LAZY_MEMBER:
1552 case MLD_AWAKENING_MEMBER:
1553 case MLD_IDLE_MEMBER:
1554 break;
1555 case MLD_G_QUERY_PENDING_MEMBER:
1556 case MLD_SG_QUERY_PENDING_MEMBER:
1557 /*
1558 * Respond to a previously pending Group-Specific
1559 * or Group-and-Source-Specific query by enqueueing
1560 * the appropriate Current-State report for
1561 * immediate transmission.
1562 */
1563 if (query_response_timer_expired) {
1564 int retval;
1565
1566 retval = mld_v2_enqueue_group_record(qrq, inm, 0, 1,
1567 (inm->in6m_state == MLD_SG_QUERY_PENDING_MEMBER),
1568 0);
1569 CTR2(KTR_MLD, "%s: enqueue record = %d",
1570 __func__, retval);
1571 inm->in6m_state = MLD_REPORTING_MEMBER;
1572 in6m_clear_recorded(inm);
1573 }
1574 /* FALLTHROUGH */
1575 case MLD_REPORTING_MEMBER:
1576 case MLD_LEAVING_MEMBER:
1577 if (state_change_retransmit_timer_expired) {
1578 /*
1579 * State-change retransmission timer fired.
1580 * If there are any further pending retransmissions,
1581 * set the global pending state-change flag, and
1582 * reset the timer.
1583 */
1584 if (--inm->in6m_scrv > 0) {
1585 inm->in6m_sctimer = uri_fasthz;
1586 V_state_change_timers_running6 = 1;
1587 }
1588 /*
1589 * Retransmit the previously computed state-change
1590 * report. If there are no further pending
1591 * retransmissions, the mbuf queue will be consumed.
1592 * Update T0 state to T1 as we have now sent
1593 * a state-change.
1594 */
1595 (void)mld_v2_merge_state_changes(inm, scq);
1596
1597 in6m_commit(inm);
1598 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
1599 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
1600 if_name(inm->in6m_ifp));
1601
1602 /*
1603 * If we are leaving the group for good, make sure
1604 * we release MLD's reference to it.
1605 * This release must be deferred using a SLIST,
1606 * as we are called from a loop which traverses
1607 * the in_ifmultiaddr TAILQ.
1608 */
1609 if (inm->in6m_state == MLD_LEAVING_MEMBER &&
1610 inm->in6m_scrv == 0) {
1611 inm->in6m_state = MLD_NOT_MEMBER;
1612 in6m_disconnect(inm);
1613 in6m_rele_locked(inmh, inm);
1614 }
1615 }
1616 break;
1617 }
1618 }
1619
1620 /*
1621 * Switch to a different version on the given interface,
1622 * as per Section 9.12.
1623 */
1624 static void
1625 mld_set_version(struct mld_ifsoftc *mli, const int version)
1626 {
1627 int old_version_timer;
1628
1629 MLD_LOCK_ASSERT();
1630
1631 CTR4(KTR_MLD, "%s: switching to v%d on ifp %p(%s)", __func__,
1632 version, mli->mli_ifp, if_name(mli->mli_ifp));
1633
1634 if (version == MLD_VERSION_1) {
1635 /*
1636 * Compute the "Older Version Querier Present" timer as per
1637 * Section 9.12.
1638 */
1639 old_version_timer = (mli->mli_rv * mli->mli_qi) + mli->mli_qri;
1640 old_version_timer *= PR_SLOWHZ;
1641 mli->mli_v1_timer = old_version_timer;
1642 }
1643
1644 if (mli->mli_v1_timer > 0 && mli->mli_version != MLD_VERSION_1) {
1645 mli->mli_version = MLD_VERSION_1;
1646 mld_v2_cancel_link_timers(mli);
1647 }
1648 }
1649
1650 /*
1651 * Cancel pending MLDv2 timers for the given link and all groups
1652 * joined on it; state-change, general-query, and group-query timers.
1653 */
1654 static void
1655 mld_v2_cancel_link_timers(struct mld_ifsoftc *mli)
1656 {
1657 struct ifmultiaddr *ifma, *next;
1658 struct ifnet *ifp;
1659 struct in6_multi *inm;
1660 struct in6_multi_head inmh;
1661
1662 CTR3(KTR_MLD, "%s: cancel v2 timers on ifp %p(%s)", __func__,
1663 mli->mli_ifp, if_name(mli->mli_ifp));
1664
1665 SLIST_INIT(&inmh);
1666 IN6_MULTI_LIST_LOCK_ASSERT();
1667 MLD_LOCK_ASSERT();
1668
1669 /*
1670 * Fast-track this potentially expensive operation
1671 * by checking all the global 'timer pending' flags.
1672 */
1673 if (!V_interface_timers_running6 &&
1674 !V_state_change_timers_running6 &&
1675 !V_current_state_timers_running6)
1676 return;
1677
1678 mli->mli_v2_timer = 0;
1679
1680 ifp = mli->mli_ifp;
1681
1682 IF_ADDR_WLOCK(ifp);
1683 restart:
1684 CK_STAILQ_FOREACH_SAFE(ifma, &ifp->if_multiaddrs, ifma_link, next) {
1685 if (ifma->ifma_addr->sa_family != AF_INET6 ||
1686 ifma->ifma_protospec == NULL)
1687 continue;
1688 inm = (struct in6_multi *)ifma->ifma_protospec;
1689 switch (inm->in6m_state) {
1690 case MLD_NOT_MEMBER:
1691 case MLD_SILENT_MEMBER:
1692 case MLD_IDLE_MEMBER:
1693 case MLD_LAZY_MEMBER:
1694 case MLD_SLEEPING_MEMBER:
1695 case MLD_AWAKENING_MEMBER:
1696 break;
1697 case MLD_LEAVING_MEMBER:
1698 /*
1699 * If we are leaving the group and switching
1700 * version, we need to release the final
1701 * reference held for issuing the INCLUDE {}.
1702 */
1703 in6m_disconnect(inm);
1704 in6m_rele_locked(&inmh, inm);
1705 ifma->ifma_protospec = NULL;
1706 /* FALLTHROUGH */
1707 case MLD_G_QUERY_PENDING_MEMBER:
1708 case MLD_SG_QUERY_PENDING_MEMBER:
1709 in6m_clear_recorded(inm);
1710 /* FALLTHROUGH */
1711 case MLD_REPORTING_MEMBER:
1712 inm->in6m_sctimer = 0;
1713 inm->in6m_timer = 0;
1714 inm->in6m_state = MLD_REPORTING_MEMBER;
1715 /*
1716 * Free any pending MLDv2 state-change records.
1717 */
1718 mbufq_drain(&inm->in6m_scq);
1719 break;
1720 }
1721 if (__predict_false(ifma6_restart)) {
1722 ifma6_restart = false;
1723 goto restart;
1724 }
1725 }
1726 IF_ADDR_WUNLOCK(ifp);
1727 in6m_release_list_deferred(&inmh);
1728 }
1729
1730 /*
1731 * Global slowtimo handler.
1732 * VIMAGE: Timeout handlers are expected to service all vimages.
1733 */
1734 void
1735 mld_slowtimo(void)
1736 {
1737 VNET_ITERATOR_DECL(vnet_iter);
1738
1739 VNET_LIST_RLOCK_NOSLEEP();
1740 VNET_FOREACH(vnet_iter) {
1741 CURVNET_SET(vnet_iter);
1742 mld_slowtimo_vnet();
1743 CURVNET_RESTORE();
1744 }
1745 VNET_LIST_RUNLOCK_NOSLEEP();
1746 }
1747
1748 /*
1749 * Per-vnet slowtimo handler.
1750 */
1751 static void
1752 mld_slowtimo_vnet(void)
1753 {
1754 struct mld_ifsoftc *mli;
1755
1756 MLD_LOCK();
1757
1758 LIST_FOREACH(mli, &V_mli_head, mli_link) {
1759 mld_v1_process_querier_timers(mli);
1760 }
1761
1762 MLD_UNLOCK();
1763 }
1764
1765 /*
1766 * Update the Older Version Querier Present timers for a link.
1767 * See Section 9.12 of RFC 3810.
1768 */
1769 static void
1770 mld_v1_process_querier_timers(struct mld_ifsoftc *mli)
1771 {
1772
1773 MLD_LOCK_ASSERT();
1774
1775 if (mli->mli_version != MLD_VERSION_2 && --mli->mli_v1_timer == 0) {
1776 /*
1777 * MLDv1 Querier Present timer expired; revert to MLDv2.
1778 */
1779 CTR5(KTR_MLD,
1780 "%s: transition from v%d -> v%d on %p(%s)",
1781 __func__, mli->mli_version, MLD_VERSION_2,
1782 mli->mli_ifp, if_name(mli->mli_ifp));
1783 mli->mli_version = MLD_VERSION_2;
1784 }
1785 }
1786
1787 /*
1788 * Transmit an MLDv1 report immediately.
1789 */
1790 static int
1791 mld_v1_transmit_report(struct in6_multi *in6m, const int type)
1792 {
1793 struct ifnet *ifp;
1794 struct in6_ifaddr *ia;
1795 struct ip6_hdr *ip6;
1796 struct mbuf *mh, *md;
1797 struct mld_hdr *mld;
1798
1799 IN6_MULTI_LIST_LOCK_ASSERT();
1800 MLD_LOCK_ASSERT();
1801
1802 ifp = in6m->in6m_ifp;
1803 /* in process of being freed */
1804 if (ifp == NULL)
1805 return (0);
1806 ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
1807 /* ia may be NULL if link-local address is tentative. */
1808
1809 mh = m_gethdr(M_NOWAIT, MT_DATA);
1810 if (mh == NULL) {
1811 if (ia != NULL)
1812 ifa_free(&ia->ia_ifa);
1813 return (ENOMEM);
1814 }
1815 md = m_get(M_NOWAIT, MT_DATA);
1816 if (md == NULL) {
1817 m_free(mh);
1818 if (ia != NULL)
1819 ifa_free(&ia->ia_ifa);
1820 return (ENOMEM);
1821 }
1822 mh->m_next = md;
1823
1824 /*
1825 * FUTURE: Consider increasing alignment by ETHER_HDR_LEN, so
1826 * that ether_output() does not need to allocate another mbuf
1827 * for the header in the most common case.
1828 */
1829 M_ALIGN(mh, sizeof(struct ip6_hdr));
1830 mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld_hdr);
1831 mh->m_len = sizeof(struct ip6_hdr);
1832
1833 ip6 = mtod(mh, struct ip6_hdr *);
1834 ip6->ip6_flow = 0;
1835 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
1836 ip6->ip6_vfc |= IPV6_VERSION;
1837 ip6->ip6_nxt = IPPROTO_ICMPV6;
1838 ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any;
1839 ip6->ip6_dst = in6m->in6m_addr;
1840
1841 md->m_len = sizeof(struct mld_hdr);
1842 mld = mtod(md, struct mld_hdr *);
1843 mld->mld_type = type;
1844 mld->mld_code = 0;
1845 mld->mld_cksum = 0;
1846 mld->mld_maxdelay = 0;
1847 mld->mld_reserved = 0;
1848 mld->mld_addr = in6m->in6m_addr;
1849 in6_clearscope(&mld->mld_addr);
1850 mld->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6,
1851 sizeof(struct ip6_hdr), sizeof(struct mld_hdr));
1852
1853 mld_save_context(mh, ifp);
1854 mh->m_flags |= M_MLDV1;
1855
1856 mld_dispatch_packet(mh);
1857
1858 if (ia != NULL)
1859 ifa_free(&ia->ia_ifa);
1860 return (0);
1861 }
1862
1863 /*
1864 * Process a state change from the upper layer for the given IPv6 group.
1865 *
1866 * Each socket holds a reference on the in_multi in its own ip_moptions.
1867 * The socket layer will have made the necessary updates to.the group
1868 * state, it is now up to MLD to issue a state change report if there
1869 * has been any change between T0 (when the last state-change was issued)
1870 * and T1 (now).
1871 *
1872 * We use the MLDv2 state machine at group level. The MLd module
1873 * however makes the decision as to which MLD protocol version to speak.
1874 * A state change *from* INCLUDE {} always means an initial join.
1875 * A state change *to* INCLUDE {} always means a final leave.
1876 *
1877 * If delay is non-zero, and the state change is an initial multicast
1878 * join, the state change report will be delayed by 'delay' ticks
1879 * in units of PR_FASTHZ if MLDv1 is active on the link; otherwise
1880 * the initial MLDv2 state change report will be delayed by whichever
1881 * is sooner, a pending state-change timer or delay itself.
1882 *
1883 * VIMAGE: curvnet should have been set by caller, as this routine
1884 * is called from the socket option handlers.
1885 */
1886 int
1887 mld_change_state(struct in6_multi *inm, const int delay)
1888 {
1889 struct mld_ifsoftc *mli;
1890 struct ifnet *ifp;
1891 int error;
1892
1893 IN6_MULTI_LIST_LOCK_ASSERT();
1894
1895 error = 0;
1896
1897 /*
1898 * Try to detect if the upper layer just asked us to change state
1899 * for an interface which has now gone away.
1900 */
1901 KASSERT(inm->in6m_ifma != NULL, ("%s: no ifma", __func__));
1902 ifp = inm->in6m_ifma->ifma_ifp;
1903 if (ifp == NULL)
1904 return (0);
1905 /*
1906 * Sanity check that netinet6's notion of ifp is the
1907 * same as net's.
1908 */
1909 KASSERT(inm->in6m_ifp == ifp, ("%s: bad ifp", __func__));
1910
1911 MLD_LOCK();
1912 mli = MLD_IFINFO(ifp);
1913 KASSERT(mli != NULL, ("%s: no mld_ifsoftc for ifp %p", __func__, ifp));
1914
1915 /*
1916 * If we detect a state transition to or from MCAST_UNDEFINED
1917 * for this group, then we are starting or finishing an MLD
1918 * life cycle for this group.
1919 */
1920 if (inm->in6m_st[1].iss_fmode != inm->in6m_st[0].iss_fmode) {
1921 CTR3(KTR_MLD, "%s: inm transition %d -> %d", __func__,
1922 inm->in6m_st[0].iss_fmode, inm->in6m_st[1].iss_fmode);
1923 if (inm->in6m_st[0].iss_fmode == MCAST_UNDEFINED) {
1924 CTR1(KTR_MLD, "%s: initial join", __func__);
1925 error = mld_initial_join(inm, mli, delay);
1926 goto out_locked;
1927 } else if (inm->in6m_st[1].iss_fmode == MCAST_UNDEFINED) {
1928 CTR1(KTR_MLD, "%s: final leave", __func__);
1929 mld_final_leave(inm, mli);
1930 goto out_locked;
1931 }
1932 } else {
1933 CTR1(KTR_MLD, "%s: filter set change", __func__);
1934 }
1935
1936 error = mld_handle_state_change(inm, mli);
1937
1938 out_locked:
1939 MLD_UNLOCK();
1940 return (error);
1941 }
1942
1943 /*
1944 * Perform the initial join for an MLD group.
1945 *
1946 * When joining a group:
1947 * If the group should have its MLD traffic suppressed, do nothing.
1948 * MLDv1 starts sending MLDv1 host membership reports.
1949 * MLDv2 will schedule an MLDv2 state-change report containing the
1950 * initial state of the membership.
1951 *
1952 * If the delay argument is non-zero, then we must delay sending the
1953 * initial state change for delay ticks (in units of PR_FASTHZ).
1954 */
1955 static int
1956 mld_initial_join(struct in6_multi *inm, struct mld_ifsoftc *mli,
1957 const int delay)
1958 {
1959 struct ifnet *ifp;
1960 struct mbufq *mq;
1961 int error, retval, syncstates;
1962 int odelay;
1963 #ifdef KTR
1964 char ip6tbuf[INET6_ADDRSTRLEN];
1965 #endif
1966
1967 CTR4(KTR_MLD, "%s: initial join %s on ifp %p(%s)",
1968 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
1969 inm->in6m_ifp, if_name(inm->in6m_ifp));
1970
1971 error = 0;
1972 syncstates = 1;
1973
1974 ifp = inm->in6m_ifp;
1975
1976 IN6_MULTI_LIST_LOCK_ASSERT();
1977 MLD_LOCK_ASSERT();
1978
1979 KASSERT(mli && mli->mli_ifp == ifp, ("%s: inconsistent ifp", __func__));
1980
1981 /*
1982 * Groups joined on loopback or marked as 'not reported',
1983 * enter the MLD_SILENT_MEMBER state and
1984 * are never reported in any protocol exchanges.
1985 * All other groups enter the appropriate state machine
1986 * for the version in use on this link.
1987 * A link marked as MLIF_SILENT causes MLD to be completely
1988 * disabled for the link.
1989 */
1990 if ((ifp->if_flags & IFF_LOOPBACK) ||
1991 (mli->mli_flags & MLIF_SILENT) ||
1992 !mld_is_addr_reported(&inm->in6m_addr)) {
1993 CTR1(KTR_MLD,
1994 "%s: not kicking state machine for silent group", __func__);
1995 inm->in6m_state = MLD_SILENT_MEMBER;
1996 inm->in6m_timer = 0;
1997 } else {
1998 /*
1999 * Deal with overlapping in_multi lifecycle.
2000 * If this group was LEAVING, then make sure
2001 * we drop the reference we picked up to keep the
2002 * group around for the final INCLUDE {} enqueue.
2003 */
2004 if (mli->mli_version == MLD_VERSION_2 &&
2005 inm->in6m_state == MLD_LEAVING_MEMBER) {
2006 inm->in6m_refcount--;
2007 }
2008 inm->in6m_state = MLD_REPORTING_MEMBER;
2009
2010 switch (mli->mli_version) {
2011 case MLD_VERSION_1:
2012 /*
2013 * If a delay was provided, only use it if
2014 * it is greater than the delay normally
2015 * used for an MLDv1 state change report,
2016 * and delay sending the initial MLDv1 report
2017 * by not transitioning to the IDLE state.
2018 */
2019 odelay = MLD_RANDOM_DELAY(MLD_V1_MAX_RI * PR_FASTHZ);
2020 if (delay) {
2021 inm->in6m_timer = max(delay, odelay);
2022 V_current_state_timers_running6 = 1;
2023 } else {
2024 inm->in6m_state = MLD_IDLE_MEMBER;
2025 error = mld_v1_transmit_report(inm,
2026 MLD_LISTENER_REPORT);
2027 if (error == 0) {
2028 inm->in6m_timer = odelay;
2029 V_current_state_timers_running6 = 1;
2030 }
2031 }
2032 break;
2033
2034 case MLD_VERSION_2:
2035 /*
2036 * Defer update of T0 to T1, until the first copy
2037 * of the state change has been transmitted.
2038 */
2039 syncstates = 0;
2040
2041 /*
2042 * Immediately enqueue a State-Change Report for
2043 * this interface, freeing any previous reports.
2044 * Don't kick the timers if there is nothing to do,
2045 * or if an error occurred.
2046 */
2047 mq = &inm->in6m_scq;
2048 mbufq_drain(mq);
2049 retval = mld_v2_enqueue_group_record(mq, inm, 1,
2050 0, 0, (mli->mli_flags & MLIF_USEALLOW));
2051 CTR2(KTR_MLD, "%s: enqueue record = %d",
2052 __func__, retval);
2053 if (retval <= 0) {
2054 error = retval * -1;
2055 break;
2056 }
2057
2058 /*
2059 * Schedule transmission of pending state-change
2060 * report up to RV times for this link. The timer
2061 * will fire at the next mld_fasttimo (~200ms),
2062 * giving us an opportunity to merge the reports.
2063 *
2064 * If a delay was provided to this function, only
2065 * use this delay if sooner than the existing one.
2066 */
2067 KASSERT(mli->mli_rv > 1,
2068 ("%s: invalid robustness %d", __func__,
2069 mli->mli_rv));
2070 inm->in6m_scrv = mli->mli_rv;
2071 if (delay) {
2072 if (inm->in6m_sctimer > 1) {
2073 inm->in6m_sctimer =
2074 min(inm->in6m_sctimer, delay);
2075 } else
2076 inm->in6m_sctimer = delay;
2077 } else
2078 inm->in6m_sctimer = 1;
2079 V_state_change_timers_running6 = 1;
2080
2081 error = 0;
2082 break;
2083 }
2084 }
2085
2086 /*
2087 * Only update the T0 state if state change is atomic,
2088 * i.e. we don't need to wait for a timer to fire before we
2089 * can consider the state change to have been communicated.
2090 */
2091 if (syncstates) {
2092 in6m_commit(inm);
2093 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
2094 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2095 if_name(inm->in6m_ifp));
2096 }
2097
2098 return (error);
2099 }
2100
2101 /*
2102 * Issue an intermediate state change during the life-cycle.
2103 */
2104 static int
2105 mld_handle_state_change(struct in6_multi *inm, struct mld_ifsoftc *mli)
2106 {
2107 struct ifnet *ifp;
2108 int retval;
2109 #ifdef KTR
2110 char ip6tbuf[INET6_ADDRSTRLEN];
2111 #endif
2112
2113 CTR4(KTR_MLD, "%s: state change for %s on ifp %p(%s)",
2114 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2115 inm->in6m_ifp, if_name(inm->in6m_ifp));
2116
2117 ifp = inm->in6m_ifp;
2118
2119 IN6_MULTI_LIST_LOCK_ASSERT();
2120 MLD_LOCK_ASSERT();
2121
2122 KASSERT(mli && mli->mli_ifp == ifp,
2123 ("%s: inconsistent ifp", __func__));
2124
2125 if ((ifp->if_flags & IFF_LOOPBACK) ||
2126 (mli->mli_flags & MLIF_SILENT) ||
2127 !mld_is_addr_reported(&inm->in6m_addr) ||
2128 (mli->mli_version != MLD_VERSION_2)) {
2129 if (!mld_is_addr_reported(&inm->in6m_addr)) {
2130 CTR1(KTR_MLD,
2131 "%s: not kicking state machine for silent group", __func__);
2132 }
2133 CTR1(KTR_MLD, "%s: nothing to do", __func__);
2134 in6m_commit(inm);
2135 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
2136 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2137 if_name(inm->in6m_ifp));
2138 return (0);
2139 }
2140
2141 mbufq_drain(&inm->in6m_scq);
2142
2143 retval = mld_v2_enqueue_group_record(&inm->in6m_scq, inm, 1, 0, 0,
2144 (mli->mli_flags & MLIF_USEALLOW));
2145 CTR2(KTR_MLD, "%s: enqueue record = %d", __func__, retval);
2146 if (retval <= 0)
2147 return (-retval);
2148
2149 /*
2150 * If record(s) were enqueued, start the state-change
2151 * report timer for this group.
2152 */
2153 inm->in6m_scrv = mli->mli_rv;
2154 inm->in6m_sctimer = 1;
2155 V_state_change_timers_running6 = 1;
2156
2157 return (0);
2158 }
2159
2160 /*
2161 * Perform the final leave for a multicast address.
2162 *
2163 * When leaving a group:
2164 * MLDv1 sends a DONE message, if and only if we are the reporter.
2165 * MLDv2 enqueues a state-change report containing a transition
2166 * to INCLUDE {} for immediate transmission.
2167 */
2168 static void
2169 mld_final_leave(struct in6_multi *inm, struct mld_ifsoftc *mli)
2170 {
2171 int syncstates;
2172 #ifdef KTR
2173 char ip6tbuf[INET6_ADDRSTRLEN];
2174 #endif
2175
2176 syncstates = 1;
2177
2178 CTR4(KTR_MLD, "%s: final leave %s on ifp %p(%s)",
2179 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2180 inm->in6m_ifp, if_name(inm->in6m_ifp));
2181
2182 IN6_MULTI_LIST_LOCK_ASSERT();
2183 MLD_LOCK_ASSERT();
2184
2185 switch (inm->in6m_state) {
2186 case MLD_NOT_MEMBER:
2187 case MLD_SILENT_MEMBER:
2188 case MLD_LEAVING_MEMBER:
2189 /* Already leaving or left; do nothing. */
2190 CTR1(KTR_MLD,
2191 "%s: not kicking state machine for silent group", __func__);
2192 break;
2193 case MLD_REPORTING_MEMBER:
2194 case MLD_IDLE_MEMBER:
2195 case MLD_G_QUERY_PENDING_MEMBER:
2196 case MLD_SG_QUERY_PENDING_MEMBER:
2197 if (mli->mli_version == MLD_VERSION_1) {
2198 #ifdef INVARIANTS
2199 if (inm->in6m_state == MLD_G_QUERY_PENDING_MEMBER ||
2200 inm->in6m_state == MLD_SG_QUERY_PENDING_MEMBER)
2201 panic("%s: MLDv2 state reached, not MLDv2 mode",
2202 __func__);
2203 #endif
2204 mld_v1_transmit_report(inm, MLD_LISTENER_DONE);
2205 inm->in6m_state = MLD_NOT_MEMBER;
2206 V_current_state_timers_running6 = 1;
2207 } else if (mli->mli_version == MLD_VERSION_2) {
2208 /*
2209 * Stop group timer and all pending reports.
2210 * Immediately enqueue a state-change report
2211 * TO_IN {} to be sent on the next fast timeout,
2212 * giving us an opportunity to merge reports.
2213 */
2214 mbufq_drain(&inm->in6m_scq);
2215 inm->in6m_timer = 0;
2216 inm->in6m_scrv = mli->mli_rv;
2217 CTR4(KTR_MLD, "%s: Leaving %s/%s with %d "
2218 "pending retransmissions.", __func__,
2219 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2220 if_name(inm->in6m_ifp), inm->in6m_scrv);
2221 if (inm->in6m_scrv == 0) {
2222 inm->in6m_state = MLD_NOT_MEMBER;
2223 inm->in6m_sctimer = 0;
2224 } else {
2225 int retval;
2226
2227 in6m_acquire_locked(inm);
2228
2229 retval = mld_v2_enqueue_group_record(
2230 &inm->in6m_scq, inm, 1, 0, 0,
2231 (mli->mli_flags & MLIF_USEALLOW));
2232 KASSERT(retval != 0,
2233 ("%s: enqueue record = %d", __func__,
2234 retval));
2235
2236 inm->in6m_state = MLD_LEAVING_MEMBER;
2237 inm->in6m_sctimer = 1;
2238 V_state_change_timers_running6 = 1;
2239 syncstates = 0;
2240 }
2241 break;
2242 }
2243 break;
2244 case MLD_LAZY_MEMBER:
2245 case MLD_SLEEPING_MEMBER:
2246 case MLD_AWAKENING_MEMBER:
2247 /* Our reports are suppressed; do nothing. */
2248 break;
2249 }
2250
2251 if (syncstates) {
2252 in6m_commit(inm);
2253 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
2254 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2255 if_name(inm->in6m_ifp));
2256 inm->in6m_st[1].iss_fmode = MCAST_UNDEFINED;
2257 CTR3(KTR_MLD, "%s: T1 now MCAST_UNDEFINED for %p/%s",
2258 __func__, &inm->in6m_addr, if_name(inm->in6m_ifp));
2259 }
2260 }
2261
2262 /*
2263 * Enqueue an MLDv2 group record to the given output queue.
2264 *
2265 * If is_state_change is zero, a current-state record is appended.
2266 * If is_state_change is non-zero, a state-change report is appended.
2267 *
2268 * If is_group_query is non-zero, an mbuf packet chain is allocated.
2269 * If is_group_query is zero, and if there is a packet with free space
2270 * at the tail of the queue, it will be appended to providing there
2271 * is enough free space.
2272 * Otherwise a new mbuf packet chain is allocated.
2273 *
2274 * If is_source_query is non-zero, each source is checked to see if
2275 * it was recorded for a Group-Source query, and will be omitted if
2276 * it is not both in-mode and recorded.
2277 *
2278 * If use_block_allow is non-zero, state change reports for initial join
2279 * and final leave, on an inclusive mode group with a source list, will be
2280 * rewritten to use the ALLOW_NEW and BLOCK_OLD record types, respectively.
2281 *
2282 * The function will attempt to allocate leading space in the packet
2283 * for the IPv6+ICMP headers to be prepended without fragmenting the chain.
2284 *
2285 * If successful the size of all data appended to the queue is returned,
2286 * otherwise an error code less than zero is returned, or zero if
2287 * no record(s) were appended.
2288 */
2289 static int
2290 mld_v2_enqueue_group_record(struct mbufq *mq, struct in6_multi *inm,
2291 const int is_state_change, const int is_group_query,
2292 const int is_source_query, const int use_block_allow)
2293 {
2294 struct mldv2_record mr;
2295 struct mldv2_record *pmr;
2296 struct ifnet *ifp;
2297 struct ip6_msource *ims, *nims;
2298 struct mbuf *m0, *m, *md;
2299 int is_filter_list_change;
2300 int minrec0len, m0srcs, msrcs, nbytes, off;
2301 int record_has_sources;
2302 int now;
2303 int type;
2304 uint8_t mode;
2305 #ifdef KTR
2306 char ip6tbuf[INET6_ADDRSTRLEN];
2307 #endif
2308
2309 IN6_MULTI_LIST_LOCK_ASSERT();
2310
2311 ifp = inm->in6m_ifp;
2312 is_filter_list_change = 0;
2313 m = NULL;
2314 m0 = NULL;
2315 m0srcs = 0;
2316 msrcs = 0;
2317 nbytes = 0;
2318 nims = NULL;
2319 record_has_sources = 1;
2320 pmr = NULL;
2321 type = MLD_DO_NOTHING;
2322 mode = inm->in6m_st[1].iss_fmode;
2323
2324 /*
2325 * If we did not transition out of ASM mode during t0->t1,
2326 * and there are no source nodes to process, we can skip
2327 * the generation of source records.
2328 */
2329 if (inm->in6m_st[0].iss_asm > 0 && inm->in6m_st[1].iss_asm > 0 &&
2330 inm->in6m_nsrc == 0)
2331 record_has_sources = 0;
2332
2333 if (is_state_change) {
2334 /*
2335 * Queue a state change record.
2336 * If the mode did not change, and there are non-ASM
2337 * listeners or source filters present,
2338 * we potentially need to issue two records for the group.
2339 * If there are ASM listeners, and there was no filter
2340 * mode transition of any kind, do nothing.
2341 *
2342 * If we are transitioning to MCAST_UNDEFINED, we need
2343 * not send any sources. A transition to/from this state is
2344 * considered inclusive with some special treatment.
2345 *
2346 * If we are rewriting initial joins/leaves to use
2347 * ALLOW/BLOCK, and the group's membership is inclusive,
2348 * we need to send sources in all cases.
2349 */
2350 if (mode != inm->in6m_st[0].iss_fmode) {
2351 if (mode == MCAST_EXCLUDE) {
2352 CTR1(KTR_MLD, "%s: change to EXCLUDE",
2353 __func__);
2354 type = MLD_CHANGE_TO_EXCLUDE_MODE;
2355 } else {
2356 CTR1(KTR_MLD, "%s: change to INCLUDE",
2357 __func__);
2358 if (use_block_allow) {
2359 /*
2360 * XXX
2361 * Here we're interested in state
2362 * edges either direction between
2363 * MCAST_UNDEFINED and MCAST_INCLUDE.
2364 * Perhaps we should just check
2365 * the group state, rather than
2366 * the filter mode.
2367 */
2368 if (mode == MCAST_UNDEFINED) {
2369 type = MLD_BLOCK_OLD_SOURCES;
2370 } else {
2371 type = MLD_ALLOW_NEW_SOURCES;
2372 }
2373 } else {
2374 type = MLD_CHANGE_TO_INCLUDE_MODE;
2375 if (mode == MCAST_UNDEFINED)
2376 record_has_sources = 0;
2377 }
2378 }
2379 } else {
2380 if (record_has_sources) {
2381 is_filter_list_change = 1;
2382 } else {
2383 type = MLD_DO_NOTHING;
2384 }
2385 }
2386 } else {
2387 /*
2388 * Queue a current state record.
2389 */
2390 if (mode == MCAST_EXCLUDE) {
2391 type = MLD_MODE_IS_EXCLUDE;
2392 } else if (mode == MCAST_INCLUDE) {
2393 type = MLD_MODE_IS_INCLUDE;
2394 KASSERT(inm->in6m_st[1].iss_asm == 0,
2395 ("%s: inm %p is INCLUDE but ASM count is %d",
2396 __func__, inm, inm->in6m_st[1].iss_asm));
2397 }
2398 }
2399
2400 /*
2401 * Generate the filter list changes using a separate function.
2402 */
2403 if (is_filter_list_change)
2404 return (mld_v2_enqueue_filter_change(mq, inm));
2405
2406 if (type == MLD_DO_NOTHING) {
2407 CTR3(KTR_MLD, "%s: nothing to do for %s/%s",
2408 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2409 if_name(inm->in6m_ifp));
2410 return (0);
2411 }
2412
2413 /*
2414 * If any sources are present, we must be able to fit at least
2415 * one in the trailing space of the tail packet's mbuf,
2416 * ideally more.
2417 */
2418 minrec0len = sizeof(struct mldv2_record);
2419 if (record_has_sources)
2420 minrec0len += sizeof(struct in6_addr);
2421
2422 CTR4(KTR_MLD, "%s: queueing %s for %s/%s", __func__,
2423 mld_rec_type_to_str(type),
2424 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2425 if_name(inm->in6m_ifp));
2426
2427 /*
2428 * Check if we have a packet in the tail of the queue for this
2429 * group into which the first group record for this group will fit.
2430 * Otherwise allocate a new packet.
2431 * Always allocate leading space for IP6+RA+ICMPV6+REPORT.
2432 * Note: Group records for G/GSR query responses MUST be sent
2433 * in their own packet.
2434 */
2435 m0 = mbufq_last(mq);
2436 if (!is_group_query &&
2437 m0 != NULL &&
2438 (m0->m_pkthdr.PH_vt.vt_nrecs + 1 <= MLD_V2_REPORT_MAXRECS) &&
2439 (m0->m_pkthdr.len + minrec0len) <
2440 (ifp->if_mtu - MLD_MTUSPACE)) {
2441 m0srcs = (ifp->if_mtu - m0->m_pkthdr.len -
2442 sizeof(struct mldv2_record)) /
2443 sizeof(struct in6_addr);
2444 m = m0;
2445 CTR1(KTR_MLD, "%s: use existing packet", __func__);
2446 } else {
2447 if (mbufq_full(mq)) {
2448 CTR1(KTR_MLD, "%s: outbound queue full", __func__);
2449 return (-ENOMEM);
2450 }
2451 m = NULL;
2452 m0srcs = (ifp->if_mtu - MLD_MTUSPACE -
2453 sizeof(struct mldv2_record)) / sizeof(struct in6_addr);
2454 if (!is_state_change && !is_group_query)
2455 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
2456 if (m == NULL)
2457 m = m_gethdr(M_NOWAIT, MT_DATA);
2458 if (m == NULL)
2459 return (-ENOMEM);
2460
2461 mld_save_context(m, ifp);
2462
2463 CTR1(KTR_MLD, "%s: allocated first packet", __func__);
2464 }
2465
2466 /*
2467 * Append group record.
2468 * If we have sources, we don't know how many yet.
2469 */
2470 mr.mr_type = type;
2471 mr.mr_datalen = 0;
2472 mr.mr_numsrc = 0;
2473 mr.mr_addr = inm->in6m_addr;
2474 in6_clearscope(&mr.mr_addr);
2475 if (!m_append(m, sizeof(struct mldv2_record), (void *)&mr)) {
2476 if (m != m0)
2477 m_freem(m);
2478 CTR1(KTR_MLD, "%s: m_append() failed.", __func__);
2479 return (-ENOMEM);
2480 }
2481 nbytes += sizeof(struct mldv2_record);
2482
2483 /*
2484 * Append as many sources as will fit in the first packet.
2485 * If we are appending to a new packet, the chain allocation
2486 * may potentially use clusters; use m_getptr() in this case.
2487 * If we are appending to an existing packet, we need to obtain
2488 * a pointer to the group record after m_append(), in case a new
2489 * mbuf was allocated.
2490 *
2491 * Only append sources which are in-mode at t1. If we are
2492 * transitioning to MCAST_UNDEFINED state on the group, and
2493 * use_block_allow is zero, do not include source entries.
2494 * Otherwise, we need to include this source in the report.
2495 *
2496 * Only report recorded sources in our filter set when responding
2497 * to a group-source query.
2498 */
2499 if (record_has_sources) {
2500 if (m == m0) {
2501 md = m_last(m);
2502 pmr = (struct mldv2_record *)(mtod(md, uint8_t *) +
2503 md->m_len - nbytes);
2504 } else {
2505 md = m_getptr(m, 0, &off);
2506 pmr = (struct mldv2_record *)(mtod(md, uint8_t *) +
2507 off);
2508 }
2509 msrcs = 0;
2510 RB_FOREACH_SAFE(ims, ip6_msource_tree, &inm->in6m_srcs,
2511 nims) {
2512 CTR2(KTR_MLD, "%s: visit node %s", __func__,
2513 ip6_sprintf(ip6tbuf, &ims->im6s_addr));
2514 now = im6s_get_mode(inm, ims, 1);
2515 CTR2(KTR_MLD, "%s: node is %d", __func__, now);
2516 if ((now != mode) ||
2517 (now == mode &&
2518 (!use_block_allow && mode == MCAST_UNDEFINED))) {
2519 CTR1(KTR_MLD, "%s: skip node", __func__);
2520 continue;
2521 }
2522 if (is_source_query && ims->im6s_stp == 0) {
2523 CTR1(KTR_MLD, "%s: skip unrecorded node",
2524 __func__);
2525 continue;
2526 }
2527 CTR1(KTR_MLD, "%s: append node", __func__);
2528 if (!m_append(m, sizeof(struct in6_addr),
2529 (void *)&ims->im6s_addr)) {
2530 if (m != m0)
2531 m_freem(m);
2532 CTR1(KTR_MLD, "%s: m_append() failed.",
2533 __func__);
2534 return (-ENOMEM);
2535 }
2536 nbytes += sizeof(struct in6_addr);
2537 ++msrcs;
2538 if (msrcs == m0srcs)
2539 break;
2540 }
2541 CTR2(KTR_MLD, "%s: msrcs is %d this packet", __func__,
2542 msrcs);
2543 pmr->mr_numsrc = htons(msrcs);
2544 nbytes += (msrcs * sizeof(struct in6_addr));
2545 }
2546
2547 if (is_source_query && msrcs == 0) {
2548 CTR1(KTR_MLD, "%s: no recorded sources to report", __func__);
2549 if (m != m0)
2550 m_freem(m);
2551 return (0);
2552 }
2553
2554 /*
2555 * We are good to go with first packet.
2556 */
2557 if (m != m0) {
2558 CTR1(KTR_MLD, "%s: enqueueing first packet", __func__);
2559 m->m_pkthdr.PH_vt.vt_nrecs = 1;
2560 mbufq_enqueue(mq, m);
2561 } else
2562 m->m_pkthdr.PH_vt.vt_nrecs++;
2563
2564 /*
2565 * No further work needed if no source list in packet(s).
2566 */
2567 if (!record_has_sources)
2568 return (nbytes);
2569
2570 /*
2571 * Whilst sources remain to be announced, we need to allocate
2572 * a new packet and fill out as many sources as will fit.
2573 * Always try for a cluster first.
2574 */
2575 while (nims != NULL) {
2576 if (mbufq_full(mq)) {
2577 CTR1(KTR_MLD, "%s: outbound queue full", __func__);
2578 return (-ENOMEM);
2579 }
2580 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
2581 if (m == NULL)
2582 m = m_gethdr(M_NOWAIT, MT_DATA);
2583 if (m == NULL)
2584 return (-ENOMEM);
2585 mld_save_context(m, ifp);
2586 md = m_getptr(m, 0, &off);
2587 pmr = (struct mldv2_record *)(mtod(md, uint8_t *) + off);
2588 CTR1(KTR_MLD, "%s: allocated next packet", __func__);
2589
2590 if (!m_append(m, sizeof(struct mldv2_record), (void *)&mr)) {
2591 if (m != m0)
2592 m_freem(m);
2593 CTR1(KTR_MLD, "%s: m_append() failed.", __func__);
2594 return (-ENOMEM);
2595 }
2596 m->m_pkthdr.PH_vt.vt_nrecs = 1;
2597 nbytes += sizeof(struct mldv2_record);
2598
2599 m0srcs = (ifp->if_mtu - MLD_MTUSPACE -
2600 sizeof(struct mldv2_record)) / sizeof(struct in6_addr);
2601
2602 msrcs = 0;
2603 RB_FOREACH_FROM(ims, ip6_msource_tree, nims) {
2604 CTR2(KTR_MLD, "%s: visit node %s",
2605 __func__, ip6_sprintf(ip6tbuf, &ims->im6s_addr));
2606 now = im6s_get_mode(inm, ims, 1);
2607 if ((now != mode) ||
2608 (now == mode &&
2609 (!use_block_allow && mode == MCAST_UNDEFINED))) {
2610 CTR1(KTR_MLD, "%s: skip node", __func__);
2611 continue;
2612 }
2613 if (is_source_query && ims->im6s_stp == 0) {
2614 CTR1(KTR_MLD, "%s: skip unrecorded node",
2615 __func__);
2616 continue;
2617 }
2618 CTR1(KTR_MLD, "%s: append node", __func__);
2619 if (!m_append(m, sizeof(struct in6_addr),
2620 (void *)&ims->im6s_addr)) {
2621 if (m != m0)
2622 m_freem(m);
2623 CTR1(KTR_MLD, "%s: m_append() failed.",
2624 __func__);
2625 return (-ENOMEM);
2626 }
2627 ++msrcs;
2628 if (msrcs == m0srcs)
2629 break;
2630 }
2631 pmr->mr_numsrc = htons(msrcs);
2632 nbytes += (msrcs * sizeof(struct in6_addr));
2633
2634 CTR1(KTR_MLD, "%s: enqueueing next packet", __func__);
2635 mbufq_enqueue(mq, m);
2636 }
2637
2638 return (nbytes);
2639 }
2640
2641 /*
2642 * Type used to mark record pass completion.
2643 * We exploit the fact we can cast to this easily from the
2644 * current filter modes on each ip_msource node.
2645 */
2646 typedef enum {
2647 REC_NONE = 0x00, /* MCAST_UNDEFINED */
2648 REC_ALLOW = 0x01, /* MCAST_INCLUDE */
2649 REC_BLOCK = 0x02, /* MCAST_EXCLUDE */
2650 REC_FULL = REC_ALLOW | REC_BLOCK
2651 } rectype_t;
2652
2653 /*
2654 * Enqueue an MLDv2 filter list change to the given output queue.
2655 *
2656 * Source list filter state is held in an RB-tree. When the filter list
2657 * for a group is changed without changing its mode, we need to compute
2658 * the deltas between T0 and T1 for each source in the filter set,
2659 * and enqueue the appropriate ALLOW_NEW/BLOCK_OLD records.
2660 *
2661 * As we may potentially queue two record types, and the entire R-B tree
2662 * needs to be walked at once, we break this out into its own function
2663 * so we can generate a tightly packed queue of packets.
2664 *
2665 * XXX This could be written to only use one tree walk, although that makes
2666 * serializing into the mbuf chains a bit harder. For now we do two walks
2667 * which makes things easier on us, and it may or may not be harder on
2668 * the L2 cache.
2669 *
2670 * If successful the size of all data appended to the queue is returned,
2671 * otherwise an error code less than zero is returned, or zero if
2672 * no record(s) were appended.
2673 */
2674 static int
2675 mld_v2_enqueue_filter_change(struct mbufq *mq, struct in6_multi *inm)
2676 {
2677 static const int MINRECLEN =
2678 sizeof(struct mldv2_record) + sizeof(struct in6_addr);
2679 struct ifnet *ifp;
2680 struct mldv2_record mr;
2681 struct mldv2_record *pmr;
2682 struct ip6_msource *ims, *nims;
2683 struct mbuf *m, *m0, *md;
2684 int m0srcs, nbytes, npbytes, off, rsrcs, schanged;
2685 int nallow, nblock;
2686 uint8_t mode, now, then;
2687 rectype_t crt, drt, nrt;
2688 #ifdef KTR
2689 char ip6tbuf[INET6_ADDRSTRLEN];
2690 #endif
2691
2692 IN6_MULTI_LIST_LOCK_ASSERT();
2693
2694 if (inm->in6m_nsrc == 0 ||
2695 (inm->in6m_st[0].iss_asm > 0 && inm->in6m_st[1].iss_asm > 0))
2696 return (0);
2697
2698 ifp = inm->in6m_ifp; /* interface */
2699 mode = inm->in6m_st[1].iss_fmode; /* filter mode at t1 */
2700 crt = REC_NONE; /* current group record type */
2701 drt = REC_NONE; /* mask of completed group record types */
2702 nrt = REC_NONE; /* record type for current node */
2703 m0srcs = 0; /* # source which will fit in current mbuf chain */
2704 npbytes = 0; /* # of bytes appended this packet */
2705 nbytes = 0; /* # of bytes appended to group's state-change queue */
2706 rsrcs = 0; /* # sources encoded in current record */
2707 schanged = 0; /* # nodes encoded in overall filter change */
2708 nallow = 0; /* # of source entries in ALLOW_NEW */
2709 nblock = 0; /* # of source entries in BLOCK_OLD */
2710 nims = NULL; /* next tree node pointer */
2711
2712 /*
2713 * For each possible filter record mode.
2714 * The first kind of source we encounter tells us which
2715 * is the first kind of record we start appending.
2716 * If a node transitioned to UNDEFINED at t1, its mode is treated
2717 * as the inverse of the group's filter mode.
2718 */
2719 while (drt != REC_FULL) {
2720 do {
2721 m0 = mbufq_last(mq);
2722 if (m0 != NULL &&
2723 (m0->m_pkthdr.PH_vt.vt_nrecs + 1 <=
2724 MLD_V2_REPORT_MAXRECS) &&
2725 (m0->m_pkthdr.len + MINRECLEN) <
2726 (ifp->if_mtu - MLD_MTUSPACE)) {
2727 m = m0;
2728 m0srcs = (ifp->if_mtu - m0->m_pkthdr.len -
2729 sizeof(struct mldv2_record)) /
2730 sizeof(struct in6_addr);
2731 CTR1(KTR_MLD,
2732 "%s: use previous packet", __func__);
2733 } else {
2734 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
2735 if (m == NULL)
2736 m = m_gethdr(M_NOWAIT, MT_DATA);
2737 if (m == NULL) {
2738 CTR1(KTR_MLD,
2739 "%s: m_get*() failed", __func__);
2740 return (-ENOMEM);
2741 }
2742 m->m_pkthdr.PH_vt.vt_nrecs = 0;
2743 mld_save_context(m, ifp);
2744 m0srcs = (ifp->if_mtu - MLD_MTUSPACE -
2745 sizeof(struct mldv2_record)) /
2746 sizeof(struct in6_addr);
2747 npbytes = 0;
2748 CTR1(KTR_MLD,
2749 "%s: allocated new packet", __func__);
2750 }
2751 /*
2752 * Append the MLD group record header to the
2753 * current packet's data area.
2754 * Recalculate pointer to free space for next
2755 * group record, in case m_append() allocated
2756 * a new mbuf or cluster.
2757 */
2758 memset(&mr, 0, sizeof(mr));
2759 mr.mr_addr = inm->in6m_addr;
2760 in6_clearscope(&mr.mr_addr);
2761 if (!m_append(m, sizeof(mr), (void *)&mr)) {
2762 if (m != m0)
2763 m_freem(m);
2764 CTR1(KTR_MLD,
2765 "%s: m_append() failed", __func__);
2766 return (-ENOMEM);
2767 }
2768 npbytes += sizeof(struct mldv2_record);
2769 if (m != m0) {
2770 /* new packet; offset in chain */
2771 md = m_getptr(m, npbytes -
2772 sizeof(struct mldv2_record), &off);
2773 pmr = (struct mldv2_record *)(mtod(md,
2774 uint8_t *) + off);
2775 } else {
2776 /* current packet; offset from last append */
2777 md = m_last(m);
2778 pmr = (struct mldv2_record *)(mtod(md,
2779 uint8_t *) + md->m_len -
2780 sizeof(struct mldv2_record));
2781 }
2782 /*
2783 * Begin walking the tree for this record type
2784 * pass, or continue from where we left off
2785 * previously if we had to allocate a new packet.
2786 * Only report deltas in-mode at t1.
2787 * We need not report included sources as allowed
2788 * if we are in inclusive mode on the group,
2789 * however the converse is not true.
2790 */
2791 rsrcs = 0;
2792 if (nims == NULL) {
2793 nims = RB_MIN(ip6_msource_tree,
2794 &inm->in6m_srcs);
2795 }
2796 RB_FOREACH_FROM(ims, ip6_msource_tree, nims) {
2797 CTR2(KTR_MLD, "%s: visit node %s", __func__,
2798 ip6_sprintf(ip6tbuf, &ims->im6s_addr));
2799 now = im6s_get_mode(inm, ims, 1);
2800 then = im6s_get_mode(inm, ims, 0);
2801 CTR3(KTR_MLD, "%s: mode: t0 %d, t1 %d",
2802 __func__, then, now);
2803 if (now == then) {
2804 CTR1(KTR_MLD,
2805 "%s: skip unchanged", __func__);
2806 continue;
2807 }
2808 if (mode == MCAST_EXCLUDE &&
2809 now == MCAST_INCLUDE) {
2810 CTR1(KTR_MLD,
2811 "%s: skip IN src on EX group",
2812 __func__);
2813 continue;
2814 }
2815 nrt = (rectype_t)now;
2816 if (nrt == REC_NONE)
2817 nrt = (rectype_t)(~mode & REC_FULL);
2818 if (schanged++ == 0) {
2819 crt = nrt;
2820 } else if (crt != nrt)
2821 continue;
2822 if (!m_append(m, sizeof(struct in6_addr),
2823 (void *)&ims->im6s_addr)) {
2824 if (m != m0)
2825 m_freem(m);
2826 CTR1(KTR_MLD,
2827 "%s: m_append() failed", __func__);
2828 return (-ENOMEM);
2829 }
2830 nallow += !!(crt == REC_ALLOW);
2831 nblock += !!(crt == REC_BLOCK);
2832 if (++rsrcs == m0srcs)
2833 break;
2834 }
2835 /*
2836 * If we did not append any tree nodes on this
2837 * pass, back out of allocations.
2838 */
2839 if (rsrcs == 0) {
2840 npbytes -= sizeof(struct mldv2_record);
2841 if (m != m0) {
2842 CTR1(KTR_MLD,
2843 "%s: m_free(m)", __func__);
2844 m_freem(m);
2845 } else {
2846 CTR1(KTR_MLD,
2847 "%s: m_adj(m, -mr)", __func__);
2848 m_adj(m, -((int)sizeof(
2849 struct mldv2_record)));
2850 }
2851 continue;
2852 }
2853 npbytes += (rsrcs * sizeof(struct in6_addr));
2854 if (crt == REC_ALLOW)
2855 pmr->mr_type = MLD_ALLOW_NEW_SOURCES;
2856 else if (crt == REC_BLOCK)
2857 pmr->mr_type = MLD_BLOCK_OLD_SOURCES;
2858 pmr->mr_numsrc = htons(rsrcs);
2859 /*
2860 * Count the new group record, and enqueue this
2861 * packet if it wasn't already queued.
2862 */
2863 m->m_pkthdr.PH_vt.vt_nrecs++;
2864 if (m != m0)
2865 mbufq_enqueue(mq, m);
2866 nbytes += npbytes;
2867 } while (nims != NULL);
2868 drt |= crt;
2869 crt = (~crt & REC_FULL);
2870 }
2871
2872 CTR3(KTR_MLD, "%s: queued %d ALLOW_NEW, %d BLOCK_OLD", __func__,
2873 nallow, nblock);
2874
2875 return (nbytes);
2876 }
2877
2878 static int
2879 mld_v2_merge_state_changes(struct in6_multi *inm, struct mbufq *scq)
2880 {
2881 struct mbufq *gq;
2882 struct mbuf *m; /* pending state-change */
2883 struct mbuf *m0; /* copy of pending state-change */
2884 struct mbuf *mt; /* last state-change in packet */
2885 int docopy, domerge;
2886 u_int recslen;
2887
2888 docopy = 0;
2889 domerge = 0;
2890 recslen = 0;
2891
2892 IN6_MULTI_LIST_LOCK_ASSERT();
2893 MLD_LOCK_ASSERT();
2894
2895 /*
2896 * If there are further pending retransmissions, make a writable
2897 * copy of each queued state-change message before merging.
2898 */
2899 if (inm->in6m_scrv > 0)
2900 docopy = 1;
2901
2902 gq = &inm->in6m_scq;
2903 #ifdef KTR
2904 if (mbufq_first(gq) == NULL) {
2905 CTR2(KTR_MLD, "%s: WARNING: queue for inm %p is empty",
2906 __func__, inm);
2907 }
2908 #endif
2909
2910 m = mbufq_first(gq);
2911 while (m != NULL) {
2912 /*
2913 * Only merge the report into the current packet if
2914 * there is sufficient space to do so; an MLDv2 report
2915 * packet may only contain 65,535 group records.
2916 * Always use a simple mbuf chain concatentation to do this,
2917 * as large state changes for single groups may have
2918 * allocated clusters.
2919 */
2920 domerge = 0;
2921 mt = mbufq_last(scq);
2922 if (mt != NULL) {
2923 recslen = m_length(m, NULL);
2924
2925 if ((mt->m_pkthdr.PH_vt.vt_nrecs +
2926 m->m_pkthdr.PH_vt.vt_nrecs <=
2927 MLD_V2_REPORT_MAXRECS) &&
2928 (mt->m_pkthdr.len + recslen <=
2929 (inm->in6m_ifp->if_mtu - MLD_MTUSPACE)))
2930 domerge = 1;
2931 }
2932
2933 if (!domerge && mbufq_full(gq)) {
2934 CTR2(KTR_MLD,
2935 "%s: outbound queue full, skipping whole packet %p",
2936 __func__, m);
2937 mt = m->m_nextpkt;
2938 if (!docopy)
2939 m_freem(m);
2940 m = mt;
2941 continue;
2942 }
2943
2944 if (!docopy) {
2945 CTR2(KTR_MLD, "%s: dequeueing %p", __func__, m);
2946 m0 = mbufq_dequeue(gq);
2947 m = m0->m_nextpkt;
2948 } else {
2949 CTR2(KTR_MLD, "%s: copying %p", __func__, m);
2950 m0 = m_dup(m, M_NOWAIT);
2951 if (m0 == NULL)
2952 return (ENOMEM);
2953 m0->m_nextpkt = NULL;
2954 m = m->m_nextpkt;
2955 }
2956
2957 if (!domerge) {
2958 CTR3(KTR_MLD, "%s: queueing %p to scq %p)",
2959 __func__, m0, scq);
2960 mbufq_enqueue(scq, m0);
2961 } else {
2962 struct mbuf *mtl; /* last mbuf of packet mt */
2963
2964 CTR3(KTR_MLD, "%s: merging %p with ifscq tail %p)",
2965 __func__, m0, mt);
2966
2967 mtl = m_last(mt);
2968 m0->m_flags &= ~M_PKTHDR;
2969 mt->m_pkthdr.len += recslen;
2970 mt->m_pkthdr.PH_vt.vt_nrecs +=
2971 m0->m_pkthdr.PH_vt.vt_nrecs;
2972
2973 mtl->m_next = m0;
2974 }
2975 }
2976
2977 return (0);
2978 }
2979
2980 /*
2981 * Respond to a pending MLDv2 General Query.
2982 */
2983 static void
2984 mld_v2_dispatch_general_query(struct mld_ifsoftc *mli)
2985 {
2986 struct ifmultiaddr *ifma;
2987 struct ifnet *ifp;
2988 struct in6_multi *inm;
2989 int retval;
2990
2991 IN6_MULTI_LIST_LOCK_ASSERT();
2992 MLD_LOCK_ASSERT();
2993
2994 KASSERT(mli->mli_version == MLD_VERSION_2,
2995 ("%s: called when version %d", __func__, mli->mli_version));
2996
2997 /*
2998 * Check that there are some packets queued. If so, send them first.
2999 * For large number of groups the reply to general query can take
3000 * many packets, we should finish sending them before starting of
3001 * queuing the new reply.
3002 */
3003 if (mbufq_len(&mli->mli_gq) != 0)
3004 goto send;
3005
3006 ifp = mli->mli_ifp;
3007
3008 IF_ADDR_RLOCK(ifp);
3009 CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
3010 if (ifma->ifma_addr->sa_family != AF_INET6 ||
3011 ifma->ifma_protospec == NULL)
3012 continue;
3013
3014 inm = (struct in6_multi *)ifma->ifma_protospec;
3015 KASSERT(ifp == inm->in6m_ifp,
3016 ("%s: inconsistent ifp", __func__));
3017
3018 switch (inm->in6m_state) {
3019 case MLD_NOT_MEMBER:
3020 case MLD_SILENT_MEMBER:
3021 break;
3022 case MLD_REPORTING_MEMBER:
3023 case MLD_IDLE_MEMBER:
3024 case MLD_LAZY_MEMBER:
3025 case MLD_SLEEPING_MEMBER:
3026 case MLD_AWAKENING_MEMBER:
3027 inm->in6m_state = MLD_REPORTING_MEMBER;
3028 retval = mld_v2_enqueue_group_record(&mli->mli_gq,
3029 inm, 0, 0, 0, 0);
3030 CTR2(KTR_MLD, "%s: enqueue record = %d",
3031 __func__, retval);
3032 break;
3033 case MLD_G_QUERY_PENDING_MEMBER:
3034 case MLD_SG_QUERY_PENDING_MEMBER:
3035 case MLD_LEAVING_MEMBER:
3036 break;
3037 }
3038 }
3039 IF_ADDR_RUNLOCK(ifp);
3040
3041 send:
3042 mld_dispatch_queue(&mli->mli_gq, MLD_MAX_RESPONSE_BURST);
3043
3044 /*
3045 * Slew transmission of bursts over 500ms intervals.
3046 */
3047 if (mbufq_first(&mli->mli_gq) != NULL) {
3048 mli->mli_v2_timer = 1 + MLD_RANDOM_DELAY(
3049 MLD_RESPONSE_BURST_INTERVAL);
3050 V_interface_timers_running6 = 1;
3051 }
3052 }
3053
3054 /*
3055 * Transmit the next pending message in the output queue.
3056 *
3057 * VIMAGE: Needs to store/restore vnet pointer on a per-mbuf-chain basis.
3058 * MRT: Nothing needs to be done, as MLD traffic is always local to
3059 * a link and uses a link-scope multicast address.
3060 */
3061 static void
3062 mld_dispatch_packet(struct mbuf *m)
3063 {
3064 struct ip6_moptions im6o;
3065 struct ifnet *ifp;
3066 struct ifnet *oifp;
3067 struct mbuf *m0;
3068 struct mbuf *md;
3069 struct ip6_hdr *ip6;
3070 struct mld_hdr *mld;
3071 int error;
3072 int off;
3073 int type;
3074 uint32_t ifindex;
3075
3076 CTR2(KTR_MLD, "%s: transmit %p", __func__, m);
3077
3078 /*
3079 * Set VNET image pointer from enqueued mbuf chain
3080 * before doing anything else. Whilst we use interface
3081 * indexes to guard against interface detach, they are
3082 * unique to each VIMAGE and must be retrieved.
3083 */
3084 ifindex = mld_restore_context(m);
3085
3086 /*
3087 * Check if the ifnet still exists. This limits the scope of
3088 * any race in the absence of a global ifp lock for low cost
3089 * (an array lookup).
3090 */
3091 ifp = ifnet_byindex(ifindex);
3092 if (ifp == NULL) {
3093 CTR3(KTR_MLD, "%s: dropped %p as ifindex %u went away.",
3094 __func__, m, ifindex);
3095 m_freem(m);
3096 IP6STAT_INC(ip6s_noroute);
3097 goto out;
3098 }
3099
3100 im6o.im6o_multicast_hlim = 1;
3101 im6o.im6o_multicast_loop = (V_ip6_mrouter != NULL);
3102 im6o.im6o_multicast_ifp = ifp;
3103
3104 if (m->m_flags & M_MLDV1) {
3105 m0 = m;
3106 } else {
3107 m0 = mld_v2_encap_report(ifp, m);
3108 if (m0 == NULL) {
3109 CTR2(KTR_MLD, "%s: dropped %p", __func__, m);
3110 IP6STAT_INC(ip6s_odropped);
3111 goto out;
3112 }
3113 }
3114
3115 mld_scrub_context(m0);
3116 m_clrprotoflags(m);
3117 m0->m_pkthdr.rcvif = V_loif;
3118
3119 ip6 = mtod(m0, struct ip6_hdr *);
3120 #if 0
3121 (void)in6_setscope(&ip6->ip6_dst, ifp, NULL); /* XXX LOR */
3122 #else
3123 /*
3124 * XXX XXX Break some KPI rules to prevent an LOR which would
3125 * occur if we called in6_setscope() at transmission.
3126 * See comments at top of file.
3127 */
3128 MLD_EMBEDSCOPE(&ip6->ip6_dst, ifp->if_index);
3129 #endif
3130
3131 /*
3132 * Retrieve the ICMPv6 type before handoff to ip6_output(),
3133 * so we can bump the stats.
3134 */
3135 md = m_getptr(m0, sizeof(struct ip6_hdr), &off);
3136 mld = (struct mld_hdr *)(mtod(md, uint8_t *) + off);
3137 type = mld->mld_type;
3138
3139 error = ip6_output(m0, &mld_po, NULL, IPV6_UNSPECSRC, &im6o,
3140 &oifp, NULL);
3141 if (error) {
3142 CTR3(KTR_MLD, "%s: ip6_output(%p) = %d", __func__, m0, error);
3143 goto out;
3144 }
3145 ICMP6STAT_INC(icp6s_outhist[type]);
3146 if (oifp != NULL) {
3147 icmp6_ifstat_inc(oifp, ifs6_out_msg);
3148 switch (type) {
3149 case MLD_LISTENER_REPORT:
3150 case MLDV2_LISTENER_REPORT:
3151 icmp6_ifstat_inc(oifp, ifs6_out_mldreport);
3152 break;
3153 case MLD_LISTENER_DONE:
3154 icmp6_ifstat_inc(oifp, ifs6_out_mlddone);
3155 break;
3156 }
3157 }
3158 out:
3159 return;
3160 }
3161
3162 /*
3163 * Encapsulate an MLDv2 report.
3164 *
3165 * KAME IPv6 requires that hop-by-hop options be passed separately,
3166 * and that the IPv6 header be prepended in a separate mbuf.
3167 *
3168 * Returns a pointer to the new mbuf chain head, or NULL if the
3169 * allocation failed.
3170 */
3171 static struct mbuf *
3172 mld_v2_encap_report(struct ifnet *ifp, struct mbuf *m)
3173 {
3174 struct mbuf *mh;
3175 struct mldv2_report *mld;
3176 struct ip6_hdr *ip6;
3177 struct in6_ifaddr *ia;
3178 int mldreclen;
3179
3180 KASSERT(ifp != NULL, ("%s: null ifp", __func__));
3181 KASSERT((m->m_flags & M_PKTHDR),
3182 ("%s: mbuf chain %p is !M_PKTHDR", __func__, m));
3183
3184 /*
3185 * RFC3590: OK to send as :: or tentative during DAD.
3186 */
3187 ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
3188 if (ia == NULL)
3189 CTR1(KTR_MLD, "%s: warning: ia is NULL", __func__);
3190
3191 mh = m_gethdr(M_NOWAIT, MT_DATA);
3192 if (mh == NULL) {
3193 if (ia != NULL)
3194 ifa_free(&ia->ia_ifa);
3195 m_freem(m);
3196 return (NULL);
3197 }
3198 M_ALIGN(mh, sizeof(struct ip6_hdr) + sizeof(struct mldv2_report));
3199
3200 mldreclen = m_length(m, NULL);
3201 CTR2(KTR_MLD, "%s: mldreclen is %d", __func__, mldreclen);
3202
3203 mh->m_len = sizeof(struct ip6_hdr) + sizeof(struct mldv2_report);
3204 mh->m_pkthdr.len = sizeof(struct ip6_hdr) +
3205 sizeof(struct mldv2_report) + mldreclen;
3206
3207 ip6 = mtod(mh, struct ip6_hdr *);
3208 ip6->ip6_flow = 0;
3209 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
3210 ip6->ip6_vfc |= IPV6_VERSION;
3211 ip6->ip6_nxt = IPPROTO_ICMPV6;
3212 ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any;
3213 if (ia != NULL)
3214 ifa_free(&ia->ia_ifa);
3215 ip6->ip6_dst = in6addr_linklocal_allv2routers;
3216 /* scope ID will be set in netisr */
3217
3218 mld = (struct mldv2_report *)(ip6 + 1);
3219 mld->mld_type = MLDV2_LISTENER_REPORT;
3220 mld->mld_code = 0;
3221 mld->mld_cksum = 0;
3222 mld->mld_v2_reserved = 0;
3223 mld->mld_v2_numrecs = htons(m->m_pkthdr.PH_vt.vt_nrecs);
3224 m->m_pkthdr.PH_vt.vt_nrecs = 0;
3225
3226 mh->m_next = m;
3227 mld->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6,
3228 sizeof(struct ip6_hdr), sizeof(struct mldv2_report) + mldreclen);
3229 return (mh);
3230 }
3231
3232 #ifdef KTR
3233 static char *
3234 mld_rec_type_to_str(const int type)
3235 {
3236
3237 switch (type) {
3238 case MLD_CHANGE_TO_EXCLUDE_MODE:
3239 return "TO_EX";
3240 break;
3241 case MLD_CHANGE_TO_INCLUDE_MODE:
3242 return "TO_IN";
3243 break;
3244 case MLD_MODE_IS_EXCLUDE:
3245 return "MODE_EX";
3246 break;
3247 case MLD_MODE_IS_INCLUDE:
3248 return "MODE_IN";
3249 break;
3250 case MLD_ALLOW_NEW_SOURCES:
3251 return "ALLOW_NEW";
3252 break;
3253 case MLD_BLOCK_OLD_SOURCES:
3254 return "BLOCK_OLD";
3255 break;
3256 default:
3257 break;
3258 }
3259 return "unknown";
3260 }
3261 #endif
3262
3263 static void
3264 mld_init(void *unused __unused)
3265 {
3266
3267 CTR1(KTR_MLD, "%s: initializing", __func__);
3268 MLD_LOCK_INIT();
3269
3270 ip6_initpktopts(&mld_po);
3271 mld_po.ip6po_hlim = 1;
3272 mld_po.ip6po_hbh = &mld_ra.hbh;
3273 mld_po.ip6po_prefer_tempaddr = IP6PO_TEMPADDR_NOTPREFER;
3274 mld_po.ip6po_flags = IP6PO_DONTFRAG;
3275 }
3276 SYSINIT(mld_init, SI_SUB_PROTO_MC, SI_ORDER_MIDDLE, mld_init, NULL);
3277
3278 static void
3279 mld_uninit(void *unused __unused)
3280 {
3281
3282 CTR1(KTR_MLD, "%s: tearing down", __func__);
3283 MLD_LOCK_DESTROY();
3284 }
3285 SYSUNINIT(mld_uninit, SI_SUB_PROTO_MC, SI_ORDER_MIDDLE, mld_uninit, NULL);
3286
3287 static void
3288 vnet_mld_init(const void *unused __unused)
3289 {
3290
3291 CTR1(KTR_MLD, "%s: initializing", __func__);
3292
3293 LIST_INIT(&V_mli_head);
3294 }
3295 VNET_SYSINIT(vnet_mld_init, SI_SUB_PROTO_MC, SI_ORDER_ANY, vnet_mld_init,
3296 NULL);
3297
3298 static void
3299 vnet_mld_uninit(const void *unused __unused)
3300 {
3301
3302 /* This can happen if we shutdown the network stack. */
3303 CTR1(KTR_MLD, "%s: tearing down", __func__);
3304 }
3305 VNET_SYSUNINIT(vnet_mld_uninit, SI_SUB_PROTO_MC, SI_ORDER_ANY, vnet_mld_uninit,
3306 NULL);
3307
3308 static int
3309 mld_modevent(module_t mod, int type, void *unused __unused)
3310 {
3311
3312 switch (type) {
3313 case MOD_LOAD:
3314 case MOD_UNLOAD:
3315 break;
3316 default:
3317 return (EOPNOTSUPP);
3318 }
3319 return (0);
3320 }
3321
3322 static moduledata_t mld_mod = {
3323 "mld",
3324 mld_modevent,
3325 0
3326 };
3327 DECLARE_MODULE(mld, mld_mod, SI_SUB_PROTO_MC, SI_ORDER_ANY);
Cache object: 3115a0c68c6f42705287a32e88e89855
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