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
66 #include <sys/cdefs.h>
67 #include "opt_inet.h"
68 #include "opt_inet6.h"
69
70 #include <sys/param.h>
71 #include <sys/systm.h>
72 #include <sys/mbuf.h>
73 #include <sys/socket.h>
74 #include <sys/sysctl.h>
75 #include <sys/kernel.h>
76 #include <sys/callout.h>
77 #include <sys/malloc.h>
78 #include <sys/module.h>
79 #include <sys/ktr.h>
80
81 #include <net/if.h>
82 #include <net/if_var.h>
83 #include <net/if_private.h>
84 #include <net/route.h>
85 #include <net/vnet.h>
86
87 #include <netinet/in.h>
88 #include <netinet/in_var.h>
89 #include <netinet6/in6_var.h>
90 #include <netinet/ip6.h>
91 #include <netinet6/ip6_var.h>
92 #include <netinet6/scope6_var.h>
93 #include <netinet/icmp6.h>
94 #include <netinet6/mld6.h>
95 #include <netinet6/mld6_var.h>
96
97 #include <security/mac/mac_framework.h>
98
99 #ifndef KTR_MLD
100 #define KTR_MLD KTR_INET6
101 #endif
102
103 static void mli_delete_locked(struct ifnet *);
104 static void mld_dispatch_packet(struct mbuf *);
105 static void mld_dispatch_queue(struct mbufq *, int);
106 static void mld_final_leave(struct in6_multi *, struct mld_ifsoftc *);
107 static void mld_fasttimo_vnet(struct in6_multi_head *inmh);
108 static int mld_handle_state_change(struct in6_multi *,
109 struct mld_ifsoftc *);
110 static int mld_initial_join(struct in6_multi *, struct mld_ifsoftc *,
111 const int);
112 #ifdef KTR
113 static char * mld_rec_type_to_str(const int);
114 #endif
115 static void mld_set_version(struct mld_ifsoftc *, const int);
116 static void mld_slowtimo_vnet(void);
117 static int mld_v1_input_query(struct ifnet *, const struct ip6_hdr *,
118 /*const*/ struct mld_hdr *);
119 static int mld_v1_input_report(struct ifnet *, const struct ip6_hdr *,
120 /*const*/ struct mld_hdr *);
121 static void mld_v1_process_group_timer(struct in6_multi_head *,
122 struct in6_multi *);
123 static void mld_v1_process_querier_timers(struct mld_ifsoftc *);
124 static int mld_v1_transmit_report(struct in6_multi *, const int);
125 static void mld_v1_update_group(struct in6_multi *, const int);
126 static void mld_v2_cancel_link_timers(struct mld_ifsoftc *);
127 static void mld_v2_dispatch_general_query(struct mld_ifsoftc *);
128 static struct mbuf *
129 mld_v2_encap_report(struct ifnet *, struct mbuf *);
130 static int mld_v2_enqueue_filter_change(struct mbufq *,
131 struct in6_multi *);
132 static int mld_v2_enqueue_group_record(struct mbufq *,
133 struct in6_multi *, const int, const int, const int,
134 const int);
135 static int mld_v2_input_query(struct ifnet *, const struct ip6_hdr *,
136 struct mbuf *, struct mldv2_query *, const int, const int);
137 static int mld_v2_merge_state_changes(struct in6_multi *,
138 struct mbufq *);
139 static void mld_v2_process_group_timers(struct in6_multi_head *,
140 struct mbufq *, struct mbufq *,
141 struct in6_multi *, const int);
142 static int mld_v2_process_group_query(struct in6_multi *,
143 struct mld_ifsoftc *mli, int, struct mbuf *,
144 struct mldv2_query *, const int);
145 static int sysctl_mld_gsr(SYSCTL_HANDLER_ARGS);
146 static int sysctl_mld_ifinfo(SYSCTL_HANDLER_ARGS);
147
148 /*
149 * Normative references: RFC 2710, RFC 3590, RFC 3810.
150 *
151 * Locking:
152 * * The MLD subsystem lock ends up being system-wide for the moment,
153 * but could be per-VIMAGE later on.
154 * * The permitted lock order is: IN6_MULTI_LOCK, MLD_LOCK, IF_ADDR_LOCK.
155 * Any may be taken independently; if any are held at the same
156 * time, the above lock order must be followed.
157 * * IN6_MULTI_LOCK covers in_multi.
158 * * MLD_LOCK covers per-link state and any global variables in this file.
159 * * IF_ADDR_LOCK covers if_multiaddrs, which is used for a variety of
160 * per-link state iterators.
161 *
162 * XXX LOR PREVENTION
163 * A special case for IPv6 is the in6_setscope() routine. ip6_output()
164 * will not accept an ifp; it wants an embedded scope ID, unlike
165 * ip_output(), which happily takes the ifp given to it. The embedded
166 * scope ID is only used by MLD to select the outgoing interface.
167 *
168 * During interface attach and detach, MLD will take MLD_LOCK *after*
169 * the IF_AFDATA_LOCK.
170 * As in6_setscope() takes IF_AFDATA_LOCK then SCOPE_LOCK, we can't call
171 * it with MLD_LOCK held without triggering an LOR. A netisr with indirect
172 * dispatch could work around this, but we'd rather not do that, as it
173 * can introduce other races.
174 *
175 * As such, we exploit the fact that the scope ID is just the interface
176 * index, and embed it in the IPv6 destination address accordingly.
177 * This is potentially NOT VALID for MLDv1 reports, as they
178 * are always sent to the multicast group itself; as MLDv2
179 * reports are always sent to ff02::16, this is not an issue
180 * when MLDv2 is in use.
181 *
182 * This does not however eliminate the LOR when ip6_output() itself
183 * calls in6_setscope() internally whilst MLD_LOCK is held. This will
184 * trigger a LOR warning in WITNESS when the ifnet is detached.
185 *
186 * The right answer is probably to make IF_AFDATA_LOCK an rwlock, given
187 * how it's used across the network stack. Here we're simply exploiting
188 * the fact that MLD runs at a similar layer in the stack to scope6.c.
189 *
190 * VIMAGE:
191 * * Each in6_multi corresponds to an ifp, and each ifp corresponds
192 * to a vnet in ifp->if_vnet.
193 */
194 static struct mtx mld_mtx;
195 static MALLOC_DEFINE(M_MLD, "mld", "mld state");
196
197 #define MLD_EMBEDSCOPE(pin6, zoneid) \
198 if (IN6_IS_SCOPE_LINKLOCAL(pin6) || \
199 IN6_IS_ADDR_MC_INTFACELOCAL(pin6)) \
200 (pin6)->s6_addr16[1] = htons((zoneid) & 0xFFFF) \
201
202 /*
203 * VIMAGE-wide globals.
204 */
205 VNET_DEFINE_STATIC(struct timeval, mld_gsrdelay) = {10, 0};
206 VNET_DEFINE_STATIC(LIST_HEAD(, mld_ifsoftc), mli_head);
207 VNET_DEFINE_STATIC(int, interface_timers_running6);
208 VNET_DEFINE_STATIC(int, state_change_timers_running6);
209 VNET_DEFINE_STATIC(int, current_state_timers_running6);
210
211 #define V_mld_gsrdelay VNET(mld_gsrdelay)
212 #define V_mli_head VNET(mli_head)
213 #define V_interface_timers_running6 VNET(interface_timers_running6)
214 #define V_state_change_timers_running6 VNET(state_change_timers_running6)
215 #define V_current_state_timers_running6 VNET(current_state_timers_running6)
216
217 SYSCTL_DECL(_net_inet6); /* Note: Not in any common header. */
218
219 SYSCTL_NODE(_net_inet6, OID_AUTO, mld, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
220 "IPv6 Multicast Listener Discovery");
221
222 /*
223 * Virtualized sysctls.
224 */
225 SYSCTL_PROC(_net_inet6_mld, OID_AUTO, gsrdelay,
226 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
227 &VNET_NAME(mld_gsrdelay.tv_sec), 0, sysctl_mld_gsr, "I",
228 "Rate limit for MLDv2 Group-and-Source queries in seconds");
229
230 /*
231 * Non-virtualized sysctls.
232 */
233 static SYSCTL_NODE(_net_inet6_mld, OID_AUTO, ifinfo,
234 CTLFLAG_RD | CTLFLAG_MPSAFE, sysctl_mld_ifinfo,
235 "Per-interface MLDv2 state");
236
237 VNET_DEFINE_STATIC(bool, mld_v1enable) = true;
238 #define V_mld_v1enable VNET(mld_v1enable)
239 SYSCTL_BOOL(_net_inet6_mld, OID_AUTO, v1enable, CTLFLAG_VNET | CTLFLAG_RWTUN,
240 &VNET_NAME(mld_v1enable), 0, "Enable fallback to MLDv1");
241
242 VNET_DEFINE_STATIC(bool, mld_v2enable) = true;
243 #define V_mld_v2enable VNET(mld_v2enable)
244 SYSCTL_BOOL(_net_inet6_mld, OID_AUTO, v2enable, CTLFLAG_VNET | CTLFLAG_RWTUN,
245 &VNET_NAME(mld_v2enable), 0, "Enable MLDv2");
246
247 VNET_DEFINE_STATIC(bool, mld_use_allow) = true;
248 #define V_mld_use_allow VNET(mld_use_allow)
249 SYSCTL_BOOL(_net_inet6_mld, OID_AUTO, use_allow, CTLFLAG_VNET | CTLFLAG_RWTUN,
250 &VNET_NAME(mld_use_allow), 0, "Use ALLOW/BLOCK for RFC 4604 SSM joins/leaves");
251
252 /*
253 * Packed Router Alert option structure declaration.
254 */
255 struct mld_raopt {
256 struct ip6_hbh hbh;
257 struct ip6_opt pad;
258 struct ip6_opt_router ra;
259 } __packed;
260
261 /*
262 * Router Alert hop-by-hop option header.
263 */
264 static struct mld_raopt mld_ra = {
265 .hbh = { 0, 0 },
266 .pad = { .ip6o_type = IP6OPT_PADN, 0 },
267 .ra = {
268 .ip6or_type = IP6OPT_ROUTER_ALERT,
269 .ip6or_len = IP6OPT_RTALERT_LEN - 2,
270 .ip6or_value[0] = ((IP6OPT_RTALERT_MLD >> 8) & 0xFF),
271 .ip6or_value[1] = (IP6OPT_RTALERT_MLD & 0xFF)
272 }
273 };
274 static struct ip6_pktopts mld_po;
275
276 static __inline void
mld_save_context(struct mbuf * m,struct ifnet * ifp)277 mld_save_context(struct mbuf *m, struct ifnet *ifp)
278 {
279
280 #ifdef VIMAGE
281 m->m_pkthdr.PH_loc.ptr = ifp->if_vnet;
282 #endif /* VIMAGE */
283 m->m_pkthdr.rcvif = ifp;
284 m->m_pkthdr.flowid = ifp->if_index;
285 }
286
287 static __inline void
mld_scrub_context(struct mbuf * m)288 mld_scrub_context(struct mbuf *m)
289 {
290
291 m->m_pkthdr.PH_loc.ptr = NULL;
292 m->m_pkthdr.flowid = 0;
293 }
294
295 /*
296 * Restore context from a queued output chain.
297 * Return saved ifindex.
298 *
299 * VIMAGE: The assertion is there to make sure that we
300 * actually called CURVNET_SET() with what's in the mbuf chain.
301 */
302 static __inline uint32_t
mld_restore_context(struct mbuf * m)303 mld_restore_context(struct mbuf *m)
304 {
305
306 #if defined(VIMAGE) && defined(INVARIANTS)
307 KASSERT(curvnet == m->m_pkthdr.PH_loc.ptr,
308 ("%s: called when curvnet was not restored: cuvnet %p m ptr %p",
309 __func__, curvnet, m->m_pkthdr.PH_loc.ptr));
310 #endif
311 return (m->m_pkthdr.flowid);
312 }
313
314 /*
315 * Retrieve or set threshold between group-source queries in seconds.
316 *
317 * VIMAGE: Assume curvnet set by caller.
318 * SMPng: NOTE: Serialized by MLD lock.
319 */
320 static int
sysctl_mld_gsr(SYSCTL_HANDLER_ARGS)321 sysctl_mld_gsr(SYSCTL_HANDLER_ARGS)
322 {
323 int error;
324 int i;
325
326 error = sysctl_wire_old_buffer(req, sizeof(int));
327 if (error)
328 return (error);
329
330 MLD_LOCK();
331
332 i = V_mld_gsrdelay.tv_sec;
333
334 error = sysctl_handle_int(oidp, &i, 0, req);
335 if (error || !req->newptr)
336 goto out_locked;
337
338 if (i < -1 || i >= 60) {
339 error = EINVAL;
340 goto out_locked;
341 }
342
343 CTR2(KTR_MLD, "change mld_gsrdelay from %d to %d",
344 V_mld_gsrdelay.tv_sec, i);
345 V_mld_gsrdelay.tv_sec = i;
346
347 out_locked:
348 MLD_UNLOCK();
349 return (error);
350 }
351
352 /*
353 * Expose struct mld_ifsoftc to userland, keyed by ifindex.
354 * For use by ifmcstat(8).
355 *
356 * VIMAGE: Assume curvnet set by caller. The node handler itself
357 * is not directly virtualized.
358 */
359 static int
sysctl_mld_ifinfo(SYSCTL_HANDLER_ARGS)360 sysctl_mld_ifinfo(SYSCTL_HANDLER_ARGS)
361 {
362 struct epoch_tracker et;
363 int *name;
364 int error;
365 u_int namelen;
366 struct ifnet *ifp;
367 struct mld_ifsoftc *mli;
368
369 name = (int *)arg1;
370 namelen = arg2;
371
372 if (req->newptr != NULL)
373 return (EPERM);
374
375 if (namelen != 1)
376 return (EINVAL);
377
378 error = sysctl_wire_old_buffer(req, sizeof(struct mld_ifinfo));
379 if (error)
380 return (error);
381
382 IN6_MULTI_LOCK();
383 IN6_MULTI_LIST_LOCK();
384 MLD_LOCK();
385 NET_EPOCH_ENTER(et);
386
387 error = ENOENT;
388 ifp = ifnet_byindex(name[0]);
389 if (ifp == NULL)
390 goto out_locked;
391
392 LIST_FOREACH(mli, &V_mli_head, mli_link) {
393 if (ifp == mli->mli_ifp) {
394 struct mld_ifinfo info;
395
396 info.mli_version = mli->mli_version;
397 info.mli_v1_timer = mli->mli_v1_timer;
398 info.mli_v2_timer = mli->mli_v2_timer;
399 info.mli_flags = mli->mli_flags;
400 info.mli_rv = mli->mli_rv;
401 info.mli_qi = mli->mli_qi;
402 info.mli_qri = mli->mli_qri;
403 info.mli_uri = mli->mli_uri;
404 error = SYSCTL_OUT(req, &info, sizeof(info));
405 break;
406 }
407 }
408
409 out_locked:
410 NET_EPOCH_EXIT(et);
411 MLD_UNLOCK();
412 IN6_MULTI_LIST_UNLOCK();
413 IN6_MULTI_UNLOCK();
414 return (error);
415 }
416
417 /*
418 * Dispatch an entire queue of pending packet chains.
419 * VIMAGE: Assumes the vnet pointer has been set.
420 */
421 static void
mld_dispatch_queue(struct mbufq * mq,int limit)422 mld_dispatch_queue(struct mbufq *mq, int limit)
423 {
424 struct mbuf *m;
425
426 while ((m = mbufq_dequeue(mq)) != NULL) {
427 CTR3(KTR_MLD, "%s: dispatch %p from %p", __func__, mq, m);
428 mld_dispatch_packet(m);
429 if (--limit == 0)
430 break;
431 }
432 }
433
434 /*
435 * Filter outgoing MLD report state by group.
436 *
437 * Reports are ALWAYS suppressed for ALL-HOSTS (ff02::1)
438 * and node-local addresses. However, kernel and socket consumers
439 * always embed the KAME scope ID in the address provided, so strip it
440 * when performing comparison.
441 * Note: This is not the same as the *multicast* scope.
442 *
443 * Return zero if the given group is one for which MLD reports
444 * should be suppressed, or non-zero if reports should be issued.
445 */
446 static __inline int
mld_is_addr_reported(const struct in6_addr * addr)447 mld_is_addr_reported(const struct in6_addr *addr)
448 {
449
450 KASSERT(IN6_IS_ADDR_MULTICAST(addr), ("%s: not multicast", __func__));
451
452 if (IPV6_ADDR_MC_SCOPE(addr) == IPV6_ADDR_SCOPE_NODELOCAL)
453 return (0);
454
455 if (IPV6_ADDR_MC_SCOPE(addr) == IPV6_ADDR_SCOPE_LINKLOCAL) {
456 struct in6_addr tmp = *addr;
457 in6_clearscope(&tmp);
458 if (IN6_ARE_ADDR_EQUAL(&tmp, &in6addr_linklocal_allnodes))
459 return (0);
460 }
461
462 return (1);
463 }
464
465 /*
466 * Attach MLD when PF_INET6 is attached to an interface. Assumes that the
467 * current VNET is set by the caller.
468 */
469 struct mld_ifsoftc *
mld_domifattach(struct ifnet * ifp)470 mld_domifattach(struct ifnet *ifp)
471 {
472 struct mld_ifsoftc *mli;
473
474 CTR3(KTR_MLD, "%s: called for ifp %p(%s)", __func__, ifp, if_name(ifp));
475
476 mli = malloc(sizeof(struct mld_ifsoftc), M_MLD, M_WAITOK | M_ZERO);
477 mli->mli_ifp = ifp;
478 mli->mli_version = MLD_VERSION_2;
479 mli->mli_flags = 0;
480 mli->mli_rv = MLD_RV_INIT;
481 mli->mli_qi = MLD_QI_INIT;
482 mli->mli_qri = MLD_QRI_INIT;
483 mli->mli_uri = MLD_URI_INIT;
484 mbufq_init(&mli->mli_gq, MLD_MAX_RESPONSE_PACKETS);
485 if ((ifp->if_flags & IFF_MULTICAST) == 0)
486 mli->mli_flags |= MLIF_SILENT;
487 if (V_mld_use_allow)
488 mli->mli_flags |= MLIF_USEALLOW;
489
490 MLD_LOCK();
491 LIST_INSERT_HEAD(&V_mli_head, mli, mli_link);
492 MLD_UNLOCK();
493
494 return (mli);
495 }
496
497 /*
498 * Hook for ifdetach.
499 *
500 * NOTE: Some finalization tasks need to run before the protocol domain
501 * is detached, but also before the link layer does its cleanup.
502 * Run before link-layer cleanup; cleanup groups, but do not free MLD state.
503 *
504 * SMPng: Caller must hold IN6_MULTI_LOCK().
505 * Must take IF_ADDR_LOCK() to cover if_multiaddrs iterator.
506 * XXX This routine is also bitten by unlocked ifma_protospec access.
507 */
508 void
mld_ifdetach(struct ifnet * ifp,struct in6_multi_head * inmh)509 mld_ifdetach(struct ifnet *ifp, struct in6_multi_head *inmh)
510 {
511 struct epoch_tracker et;
512 struct mld_ifsoftc *mli;
513 struct ifmultiaddr *ifma;
514 struct in6_multi *inm;
515
516 CTR3(KTR_MLD, "%s: called for ifp %p(%s)", __func__, ifp,
517 if_name(ifp));
518
519 IN6_MULTI_LIST_LOCK_ASSERT();
520 MLD_LOCK();
521
522 mli = MLD_IFINFO(ifp);
523 IF_ADDR_WLOCK(ifp);
524 /*
525 * Extract list of in6_multi associated with the detaching ifp
526 * which the PF_INET6 layer is about to release.
527 */
528 NET_EPOCH_ENTER(et);
529 CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
530 inm = in6m_ifmultiaddr_get_inm(ifma);
531 if (inm == NULL)
532 continue;
533 in6m_disconnect_locked(inmh, inm);
534
535 if (mli->mli_version == MLD_VERSION_2) {
536 in6m_clear_recorded(inm);
537
538 /*
539 * We need to release the final reference held
540 * for issuing the INCLUDE {}.
541 */
542 if (inm->in6m_state == MLD_LEAVING_MEMBER) {
543 inm->in6m_state = MLD_NOT_MEMBER;
544 in6m_rele_locked(inmh, inm);
545 }
546 }
547 }
548 NET_EPOCH_EXIT(et);
549 IF_ADDR_WUNLOCK(ifp);
550 MLD_UNLOCK();
551 }
552
553 /*
554 * Hook for domifdetach.
555 * Runs after link-layer cleanup; free MLD state.
556 *
557 * SMPng: Normally called with IF_AFDATA_LOCK held.
558 */
559 void
mld_domifdetach(struct ifnet * ifp)560 mld_domifdetach(struct ifnet *ifp)
561 {
562
563 CTR3(KTR_MLD, "%s: called for ifp %p(%s)",
564 __func__, ifp, if_name(ifp));
565
566 MLD_LOCK();
567 mli_delete_locked(ifp);
568 MLD_UNLOCK();
569 }
570
571 static void
mli_delete_locked(struct ifnet * ifp)572 mli_delete_locked(struct ifnet *ifp)
573 {
574 struct mld_ifsoftc *mli, *tmli;
575
576 CTR3(KTR_MLD, "%s: freeing mld_ifsoftc for ifp %p(%s)",
577 __func__, ifp, if_name(ifp));
578
579 MLD_LOCK_ASSERT();
580
581 LIST_FOREACH_SAFE(mli, &V_mli_head, mli_link, tmli) {
582 if (mli->mli_ifp == ifp) {
583 /*
584 * Free deferred General Query responses.
585 */
586 mbufq_drain(&mli->mli_gq);
587
588 LIST_REMOVE(mli, mli_link);
589
590 free(mli, M_MLD);
591 return;
592 }
593 }
594 }
595
596 /*
597 * Process a received MLDv1 general or address-specific query.
598 * Assumes that the query header has been pulled up to sizeof(mld_hdr).
599 *
600 * NOTE: Can't be fully const correct as we temporarily embed scope ID in
601 * mld_addr. This is OK as we own the mbuf chain.
602 */
603 static int
mld_v1_input_query(struct ifnet * ifp,const struct ip6_hdr * ip6,struct mld_hdr * mld)604 mld_v1_input_query(struct ifnet *ifp, const struct ip6_hdr *ip6,
605 /*const*/ struct mld_hdr *mld)
606 {
607 struct ifmultiaddr *ifma;
608 struct mld_ifsoftc *mli;
609 struct in6_multi *inm;
610 int is_general_query;
611 uint16_t timer;
612 #ifdef KTR
613 char ip6tbuf[INET6_ADDRSTRLEN];
614 #endif
615
616 NET_EPOCH_ASSERT();
617
618 is_general_query = 0;
619
620 if (!V_mld_v1enable) {
621 CTR3(KTR_MLD, "ignore v1 query %s on ifp %p(%s)",
622 ip6_sprintf(ip6tbuf, &mld->mld_addr),
623 ifp, if_name(ifp));
624 return (0);
625 }
626
627 /*
628 * RFC3810 Section 6.2: MLD queries must originate from
629 * a router's link-local address.
630 */
631 if (!IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
632 CTR3(KTR_MLD, "ignore v1 query src %s on ifp %p(%s)",
633 ip6_sprintf(ip6tbuf, &ip6->ip6_src),
634 ifp, if_name(ifp));
635 return (0);
636 }
637
638 /*
639 * Do address field validation upfront before we accept
640 * the query.
641 */
642 if (IN6_IS_ADDR_UNSPECIFIED(&mld->mld_addr)) {
643 /*
644 * MLDv1 General Query.
645 * If this was not sent to the all-nodes group, ignore it.
646 */
647 struct in6_addr dst;
648
649 dst = ip6->ip6_dst;
650 in6_clearscope(&dst);
651 if (!IN6_ARE_ADDR_EQUAL(&dst, &in6addr_linklocal_allnodes))
652 return (EINVAL);
653 is_general_query = 1;
654 } else {
655 /*
656 * Embed scope ID of receiving interface in MLD query for
657 * lookup whilst we don't hold other locks.
658 */
659 in6_setscope(&mld->mld_addr, ifp, NULL);
660 }
661
662 IN6_MULTI_LIST_LOCK();
663 MLD_LOCK();
664
665 /*
666 * Switch to MLDv1 host compatibility mode.
667 */
668 mli = MLD_IFINFO(ifp);
669 KASSERT(mli != NULL, ("%s: no mld_ifsoftc for ifp %p", __func__, ifp));
670 mld_set_version(mli, MLD_VERSION_1);
671
672 timer = (ntohs(mld->mld_maxdelay) * MLD_FASTHZ) / MLD_TIMER_SCALE;
673 if (timer == 0)
674 timer = 1;
675
676 if (is_general_query) {
677 /*
678 * For each reporting group joined on this
679 * interface, kick the report timer.
680 */
681 CTR2(KTR_MLD, "process v1 general query on ifp %p(%s)",
682 ifp, if_name(ifp));
683 CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
684 inm = in6m_ifmultiaddr_get_inm(ifma);
685 if (inm == NULL)
686 continue;
687 mld_v1_update_group(inm, timer);
688 }
689 } else {
690 /*
691 * MLDv1 Group-Specific Query.
692 * If this is a group-specific MLDv1 query, we need only
693 * look up the single group to process it.
694 */
695 inm = in6m_lookup_locked(ifp, &mld->mld_addr);
696 if (inm != NULL) {
697 CTR3(KTR_MLD, "process v1 query %s on ifp %p(%s)",
698 ip6_sprintf(ip6tbuf, &mld->mld_addr),
699 ifp, if_name(ifp));
700 mld_v1_update_group(inm, timer);
701 }
702 /* XXX Clear embedded scope ID as userland won't expect it. */
703 in6_clearscope(&mld->mld_addr);
704 }
705
706 MLD_UNLOCK();
707 IN6_MULTI_LIST_UNLOCK();
708
709 return (0);
710 }
711
712 /*
713 * Update the report timer on a group in response to an MLDv1 query.
714 *
715 * If we are becoming the reporting member for this group, start the timer.
716 * If we already are the reporting member for this group, and timer is
717 * below the threshold, reset it.
718 *
719 * We may be updating the group for the first time since we switched
720 * to MLDv2. If we are, then we must clear any recorded source lists,
721 * and transition to REPORTING state; the group timer is overloaded
722 * for group and group-source query responses.
723 *
724 * Unlike MLDv2, the delay per group should be jittered
725 * to avoid bursts of MLDv1 reports.
726 */
727 static void
mld_v1_update_group(struct in6_multi * inm,const int timer)728 mld_v1_update_group(struct in6_multi *inm, const int timer)
729 {
730 #ifdef KTR
731 char ip6tbuf[INET6_ADDRSTRLEN];
732 #endif
733
734 CTR4(KTR_MLD, "%s: %s/%s timer=%d", __func__,
735 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
736 if_name(inm->in6m_ifp), timer);
737
738 IN6_MULTI_LIST_LOCK_ASSERT();
739
740 switch (inm->in6m_state) {
741 case MLD_NOT_MEMBER:
742 case MLD_SILENT_MEMBER:
743 break;
744 case MLD_REPORTING_MEMBER:
745 if (inm->in6m_timer != 0 &&
746 inm->in6m_timer <= timer) {
747 CTR1(KTR_MLD, "%s: REPORTING and timer running, "
748 "skipping.", __func__);
749 break;
750 }
751 /* FALLTHROUGH */
752 case MLD_SG_QUERY_PENDING_MEMBER:
753 case MLD_G_QUERY_PENDING_MEMBER:
754 case MLD_IDLE_MEMBER:
755 case MLD_LAZY_MEMBER:
756 case MLD_AWAKENING_MEMBER:
757 CTR1(KTR_MLD, "%s: ->REPORTING", __func__);
758 inm->in6m_state = MLD_REPORTING_MEMBER;
759 inm->in6m_timer = MLD_RANDOM_DELAY(timer);
760 V_current_state_timers_running6 = 1;
761 break;
762 case MLD_SLEEPING_MEMBER:
763 CTR1(KTR_MLD, "%s: ->AWAKENING", __func__);
764 inm->in6m_state = MLD_AWAKENING_MEMBER;
765 break;
766 case MLD_LEAVING_MEMBER:
767 break;
768 }
769 }
770
771 /*
772 * Process a received MLDv2 general, group-specific or
773 * group-and-source-specific query.
774 *
775 * Assumes that mld points to a struct mldv2_query which is stored in
776 * contiguous memory.
777 *
778 * Return 0 if successful, otherwise an appropriate error code is returned.
779 */
780 static int
mld_v2_input_query(struct ifnet * ifp,const struct ip6_hdr * ip6,struct mbuf * m,struct mldv2_query * mld,const int off,const int icmp6len)781 mld_v2_input_query(struct ifnet *ifp, const struct ip6_hdr *ip6,
782 struct mbuf *m, struct mldv2_query *mld, const int off, const int icmp6len)
783 {
784 struct mld_ifsoftc *mli;
785 struct in6_multi *inm;
786 uint32_t maxdelay, nsrc, qqi;
787 int is_general_query;
788 uint16_t timer;
789 uint8_t qrv;
790 #ifdef KTR
791 char ip6tbuf[INET6_ADDRSTRLEN];
792 #endif
793
794 NET_EPOCH_ASSERT();
795
796 if (!V_mld_v2enable) {
797 CTR3(KTR_MLD, "ignore v2 query src %s on ifp %p(%s)",
798 ip6_sprintf(ip6tbuf, &ip6->ip6_src),
799 ifp, if_name(ifp));
800 return (0);
801 }
802
803 /*
804 * RFC3810 Section 6.2: MLD queries must originate from
805 * a router's link-local address.
806 */
807 if (!IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
808 CTR3(KTR_MLD, "ignore v1 query src %s on ifp %p(%s)",
809 ip6_sprintf(ip6tbuf, &ip6->ip6_src),
810 ifp, if_name(ifp));
811 return (0);
812 }
813
814 is_general_query = 0;
815
816 CTR2(KTR_MLD, "input v2 query on ifp %p(%s)", ifp, if_name(ifp));
817
818 maxdelay = ntohs(mld->mld_maxdelay); /* in 1/10ths of a second */
819 if (maxdelay >= 32768) {
820 maxdelay = (MLD_MRC_MANT(maxdelay) | 0x1000) <<
821 (MLD_MRC_EXP(maxdelay) + 3);
822 }
823 timer = (maxdelay * MLD_FASTHZ) / MLD_TIMER_SCALE;
824 if (timer == 0)
825 timer = 1;
826
827 qrv = MLD_QRV(mld->mld_misc);
828 if (qrv < 2) {
829 CTR3(KTR_MLD, "%s: clamping qrv %d to %d", __func__,
830 qrv, MLD_RV_INIT);
831 qrv = MLD_RV_INIT;
832 }
833
834 qqi = mld->mld_qqi;
835 if (qqi >= 128) {
836 qqi = MLD_QQIC_MANT(mld->mld_qqi) <<
837 (MLD_QQIC_EXP(mld->mld_qqi) + 3);
838 }
839
840 nsrc = ntohs(mld->mld_numsrc);
841 if (nsrc > MLD_MAX_GS_SOURCES)
842 return (EMSGSIZE);
843 if (icmp6len < sizeof(struct mldv2_query) +
844 (nsrc * sizeof(struct in6_addr)))
845 return (EMSGSIZE);
846
847 /*
848 * Do further input validation upfront to avoid resetting timers
849 * should we need to discard this query.
850 */
851 if (IN6_IS_ADDR_UNSPECIFIED(&mld->mld_addr)) {
852 /*
853 * A general query with a source list has undefined
854 * behaviour; discard it.
855 */
856 if (nsrc > 0)
857 return (EINVAL);
858 is_general_query = 1;
859 } else {
860 /*
861 * Embed scope ID of receiving interface in MLD query for
862 * lookup whilst we don't hold other locks (due to KAME
863 * locking lameness). We own this mbuf chain just now.
864 */
865 in6_setscope(&mld->mld_addr, ifp, NULL);
866 }
867
868 IN6_MULTI_LIST_LOCK();
869 MLD_LOCK();
870
871 mli = MLD_IFINFO(ifp);
872 KASSERT(mli != NULL, ("%s: no mld_ifsoftc for ifp %p", __func__, ifp));
873
874 /*
875 * Discard the v2 query if we're in Compatibility Mode.
876 * The RFC is pretty clear that hosts need to stay in MLDv1 mode
877 * until the Old Version Querier Present timer expires.
878 */
879 if (mli->mli_version != MLD_VERSION_2)
880 goto out_locked;
881
882 mld_set_version(mli, MLD_VERSION_2);
883 mli->mli_rv = qrv;
884 mli->mli_qi = qqi;
885 mli->mli_qri = maxdelay;
886
887 CTR4(KTR_MLD, "%s: qrv %d qi %d maxdelay %d", __func__, qrv, qqi,
888 maxdelay);
889
890 if (is_general_query) {
891 /*
892 * MLDv2 General Query.
893 *
894 * Schedule a current-state report on this ifp for
895 * all groups, possibly containing source lists.
896 *
897 * If there is a pending General Query response
898 * scheduled earlier than the selected delay, do
899 * not schedule any other reports.
900 * Otherwise, reset the interface timer.
901 */
902 CTR2(KTR_MLD, "process v2 general query on ifp %p(%s)",
903 ifp, if_name(ifp));
904 if (mli->mli_v2_timer == 0 || mli->mli_v2_timer >= timer) {
905 mli->mli_v2_timer = MLD_RANDOM_DELAY(timer);
906 V_interface_timers_running6 = 1;
907 }
908 } else {
909 /*
910 * MLDv2 Group-specific or Group-and-source-specific Query.
911 *
912 * Group-source-specific queries are throttled on
913 * a per-group basis to defeat denial-of-service attempts.
914 * Queries for groups we are not a member of on this
915 * link are simply ignored.
916 */
917 inm = in6m_lookup_locked(ifp, &mld->mld_addr);
918 if (inm == NULL)
919 goto out_locked;
920 if (nsrc > 0) {
921 if (!ratecheck(&inm->in6m_lastgsrtv,
922 &V_mld_gsrdelay)) {
923 CTR1(KTR_MLD, "%s: GS query throttled.",
924 __func__);
925 goto out_locked;
926 }
927 }
928 CTR2(KTR_MLD, "process v2 group query on ifp %p(%s)",
929 ifp, if_name(ifp));
930 /*
931 * If there is a pending General Query response
932 * scheduled sooner than the selected delay, no
933 * further report need be scheduled.
934 * Otherwise, prepare to respond to the
935 * group-specific or group-and-source query.
936 */
937 if (mli->mli_v2_timer == 0 || mli->mli_v2_timer >= timer)
938 mld_v2_process_group_query(inm, mli, timer, m, mld, off);
939
940 /* XXX Clear embedded scope ID as userland won't expect it. */
941 in6_clearscope(&mld->mld_addr);
942 }
943
944 out_locked:
945 MLD_UNLOCK();
946 IN6_MULTI_LIST_UNLOCK();
947
948 return (0);
949 }
950
951 /*
952 * Process a received MLDv2 group-specific or group-and-source-specific
953 * query.
954 * Return <0 if any error occurred. Currently this is ignored.
955 */
956 static int
mld_v2_process_group_query(struct in6_multi * inm,struct mld_ifsoftc * mli,int timer,struct mbuf * m0,struct mldv2_query * mld,const int off)957 mld_v2_process_group_query(struct in6_multi *inm, struct mld_ifsoftc *mli,
958 int timer, struct mbuf *m0, struct mldv2_query *mld, const int off)
959 {
960 int retval;
961 uint16_t nsrc;
962
963 IN6_MULTI_LIST_LOCK_ASSERT();
964 MLD_LOCK_ASSERT();
965
966 retval = 0;
967
968 switch (inm->in6m_state) {
969 case MLD_NOT_MEMBER:
970 case MLD_SILENT_MEMBER:
971 case MLD_SLEEPING_MEMBER:
972 case MLD_LAZY_MEMBER:
973 case MLD_AWAKENING_MEMBER:
974 case MLD_IDLE_MEMBER:
975 case MLD_LEAVING_MEMBER:
976 return (retval);
977 break;
978 case MLD_REPORTING_MEMBER:
979 case MLD_G_QUERY_PENDING_MEMBER:
980 case MLD_SG_QUERY_PENDING_MEMBER:
981 break;
982 }
983
984 nsrc = ntohs(mld->mld_numsrc);
985
986 /* Length should be checked by calling function. */
987 KASSERT((m0->m_flags & M_PKTHDR) == 0 ||
988 m0->m_pkthdr.len >= off + sizeof(struct mldv2_query) +
989 nsrc * sizeof(struct in6_addr),
990 ("mldv2 packet is too short: (%d bytes < %zd bytes, m=%p)",
991 m0->m_pkthdr.len, off + sizeof(struct mldv2_query) +
992 nsrc * sizeof(struct in6_addr), m0));
993
994 /*
995 * Deal with group-specific queries upfront.
996 * If any group query is already pending, purge any recorded
997 * source-list state if it exists, and schedule a query response
998 * for this group-specific query.
999 */
1000 if (nsrc == 0) {
1001 if (inm->in6m_state == MLD_G_QUERY_PENDING_MEMBER ||
1002 inm->in6m_state == MLD_SG_QUERY_PENDING_MEMBER) {
1003 in6m_clear_recorded(inm);
1004 timer = min(inm->in6m_timer, timer);
1005 }
1006 inm->in6m_state = MLD_G_QUERY_PENDING_MEMBER;
1007 inm->in6m_timer = MLD_RANDOM_DELAY(timer);
1008 V_current_state_timers_running6 = 1;
1009 return (retval);
1010 }
1011
1012 /*
1013 * Deal with the case where a group-and-source-specific query has
1014 * been received but a group-specific query is already pending.
1015 */
1016 if (inm->in6m_state == MLD_G_QUERY_PENDING_MEMBER) {
1017 timer = min(inm->in6m_timer, timer);
1018 inm->in6m_timer = MLD_RANDOM_DELAY(timer);
1019 V_current_state_timers_running6 = 1;
1020 return (retval);
1021 }
1022
1023 /*
1024 * Finally, deal with the case where a group-and-source-specific
1025 * query has been received, where a response to a previous g-s-r
1026 * query exists, or none exists.
1027 * In this case, we need to parse the source-list which the Querier
1028 * has provided us with and check if we have any source list filter
1029 * entries at T1 for these sources. If we do not, there is no need
1030 * schedule a report and the query may be dropped.
1031 * If we do, we must record them and schedule a current-state
1032 * report for those sources.
1033 */
1034 if (inm->in6m_nsrc > 0) {
1035 struct in6_addr srcaddr;
1036 int i, nrecorded;
1037 int soff;
1038
1039 soff = off + sizeof(struct mldv2_query);
1040 nrecorded = 0;
1041 for (i = 0; i < nsrc; i++) {
1042 m_copydata(m0, soff, sizeof(struct in6_addr),
1043 (caddr_t)&srcaddr);
1044 retval = in6m_record_source(inm, &srcaddr);
1045 if (retval < 0)
1046 break;
1047 nrecorded += retval;
1048 soff += sizeof(struct in6_addr);
1049 }
1050 if (nrecorded > 0) {
1051 CTR1(KTR_MLD,
1052 "%s: schedule response to SG query", __func__);
1053 inm->in6m_state = MLD_SG_QUERY_PENDING_MEMBER;
1054 inm->in6m_timer = MLD_RANDOM_DELAY(timer);
1055 V_current_state_timers_running6 = 1;
1056 }
1057 }
1058
1059 return (retval);
1060 }
1061
1062 /*
1063 * Process a received MLDv1 host membership report.
1064 * Assumes mld points to mld_hdr in pulled up mbuf chain.
1065 *
1066 * NOTE: Can't be fully const correct as we temporarily embed scope ID in
1067 * mld_addr. This is OK as we own the mbuf chain.
1068 */
1069 static int
mld_v1_input_report(struct ifnet * ifp,const struct ip6_hdr * ip6,struct mld_hdr * mld)1070 mld_v1_input_report(struct ifnet *ifp, const struct ip6_hdr *ip6,
1071 /*const*/ struct mld_hdr *mld)
1072 {
1073 struct in6_addr src, dst;
1074 struct in6_ifaddr *ia;
1075 struct in6_multi *inm;
1076 #ifdef KTR
1077 char ip6tbuf[INET6_ADDRSTRLEN];
1078 #endif
1079
1080 NET_EPOCH_ASSERT();
1081
1082 if (!V_mld_v1enable) {
1083 CTR3(KTR_MLD, "ignore v1 report %s on ifp %p(%s)",
1084 ip6_sprintf(ip6tbuf, &mld->mld_addr),
1085 ifp, if_name(ifp));
1086 return (0);
1087 }
1088
1089 if (ifp->if_flags & IFF_LOOPBACK)
1090 return (0);
1091
1092 /*
1093 * MLDv1 reports must originate from a host's link-local address,
1094 * or the unspecified address (when booting).
1095 */
1096 src = ip6->ip6_src;
1097 in6_clearscope(&src);
1098 if (!IN6_IS_SCOPE_LINKLOCAL(&src) && !IN6_IS_ADDR_UNSPECIFIED(&src)) {
1099 CTR3(KTR_MLD, "ignore v1 query src %s on ifp %p(%s)",
1100 ip6_sprintf(ip6tbuf, &ip6->ip6_src),
1101 ifp, if_name(ifp));
1102 return (EINVAL);
1103 }
1104
1105 /*
1106 * RFC2710 Section 4: MLDv1 reports must pertain to a multicast
1107 * group, and must be directed to the group itself.
1108 */
1109 dst = ip6->ip6_dst;
1110 in6_clearscope(&dst);
1111 if (!IN6_IS_ADDR_MULTICAST(&mld->mld_addr) ||
1112 !IN6_ARE_ADDR_EQUAL(&mld->mld_addr, &dst)) {
1113 CTR3(KTR_MLD, "ignore v1 query dst %s on ifp %p(%s)",
1114 ip6_sprintf(ip6tbuf, &ip6->ip6_dst),
1115 ifp, if_name(ifp));
1116 return (EINVAL);
1117 }
1118
1119 /*
1120 * Make sure we don't hear our own membership report, as fast
1121 * leave requires knowing that we are the only member of a
1122 * group. Assume we used the link-local address if available,
1123 * otherwise look for ::.
1124 *
1125 * XXX Note that scope ID comparison is needed for the address
1126 * returned by in6ifa_ifpforlinklocal(), but SHOULD NOT be
1127 * performed for the on-wire address.
1128 */
1129 ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
1130 if ((ia && IN6_ARE_ADDR_EQUAL(&ip6->ip6_src, IA6_IN6(ia))) ||
1131 (ia == NULL && IN6_IS_ADDR_UNSPECIFIED(&src))) {
1132 if (ia != NULL)
1133 ifa_free(&ia->ia_ifa);
1134 return (0);
1135 }
1136 if (ia != NULL)
1137 ifa_free(&ia->ia_ifa);
1138
1139 CTR3(KTR_MLD, "process v1 report %s on ifp %p(%s)",
1140 ip6_sprintf(ip6tbuf, &mld->mld_addr), ifp, if_name(ifp));
1141
1142 /*
1143 * Embed scope ID of receiving interface in MLD query for lookup
1144 * whilst we don't hold other locks (due to KAME locking lameness).
1145 */
1146 if (!IN6_IS_ADDR_UNSPECIFIED(&mld->mld_addr))
1147 in6_setscope(&mld->mld_addr, ifp, NULL);
1148
1149 IN6_MULTI_LIST_LOCK();
1150 MLD_LOCK();
1151
1152 /*
1153 * MLDv1 report suppression.
1154 * If we are a member of this group, and our membership should be
1155 * reported, and our group timer is pending or about to be reset,
1156 * stop our group timer by transitioning to the 'lazy' state.
1157 */
1158 inm = in6m_lookup_locked(ifp, &mld->mld_addr);
1159 if (inm != NULL) {
1160 struct mld_ifsoftc *mli;
1161
1162 mli = inm->in6m_mli;
1163 KASSERT(mli != NULL,
1164 ("%s: no mli for ifp %p", __func__, ifp));
1165
1166 /*
1167 * If we are in MLDv2 host mode, do not allow the
1168 * other host's MLDv1 report to suppress our reports.
1169 */
1170 if (mli->mli_version == MLD_VERSION_2)
1171 goto out_locked;
1172
1173 inm->in6m_timer = 0;
1174
1175 switch (inm->in6m_state) {
1176 case MLD_NOT_MEMBER:
1177 case MLD_SILENT_MEMBER:
1178 case MLD_SLEEPING_MEMBER:
1179 break;
1180 case MLD_REPORTING_MEMBER:
1181 case MLD_IDLE_MEMBER:
1182 case MLD_AWAKENING_MEMBER:
1183 CTR3(KTR_MLD,
1184 "report suppressed for %s on ifp %p(%s)",
1185 ip6_sprintf(ip6tbuf, &mld->mld_addr),
1186 ifp, if_name(ifp));
1187 case MLD_LAZY_MEMBER:
1188 inm->in6m_state = MLD_LAZY_MEMBER;
1189 break;
1190 case MLD_G_QUERY_PENDING_MEMBER:
1191 case MLD_SG_QUERY_PENDING_MEMBER:
1192 case MLD_LEAVING_MEMBER:
1193 break;
1194 }
1195 }
1196
1197 out_locked:
1198 MLD_UNLOCK();
1199 IN6_MULTI_LIST_UNLOCK();
1200
1201 /* XXX Clear embedded scope ID as userland won't expect it. */
1202 in6_clearscope(&mld->mld_addr);
1203
1204 return (0);
1205 }
1206
1207 /*
1208 * MLD input path.
1209 *
1210 * Assume query messages which fit in a single ICMPv6 message header
1211 * have been pulled up.
1212 * Assume that userland will want to see the message, even if it
1213 * otherwise fails kernel input validation; do not free it.
1214 * Pullup may however free the mbuf chain m if it fails.
1215 *
1216 * Return IPPROTO_DONE if we freed m. Otherwise, return 0.
1217 */
1218 int
mld_input(struct mbuf ** mp,int off,int icmp6len)1219 mld_input(struct mbuf **mp, int off, int icmp6len)
1220 {
1221 struct ifnet *ifp;
1222 struct ip6_hdr *ip6;
1223 struct mbuf *m;
1224 struct mld_hdr *mld;
1225 int mldlen;
1226
1227 m = *mp;
1228 CTR3(KTR_MLD, "%s: called w/mbuf (%p,%d)", __func__, m, off);
1229
1230 ifp = m->m_pkthdr.rcvif;
1231
1232 /* Pullup to appropriate size. */
1233 if (m->m_len < off + sizeof(*mld)) {
1234 m = m_pullup(m, off + sizeof(*mld));
1235 if (m == NULL) {
1236 ICMP6STAT_INC(icp6s_badlen);
1237 return (IPPROTO_DONE);
1238 }
1239 }
1240 mld = (struct mld_hdr *)(mtod(m, uint8_t *) + off);
1241 if (mld->mld_type == MLD_LISTENER_QUERY &&
1242 icmp6len >= sizeof(struct mldv2_query)) {
1243 mldlen = sizeof(struct mldv2_query);
1244 } else {
1245 mldlen = sizeof(struct mld_hdr);
1246 }
1247 if (m->m_len < off + mldlen) {
1248 m = m_pullup(m, off + mldlen);
1249 if (m == NULL) {
1250 ICMP6STAT_INC(icp6s_badlen);
1251 return (IPPROTO_DONE);
1252 }
1253 }
1254 *mp = m;
1255 ip6 = mtod(m, struct ip6_hdr *);
1256 mld = (struct mld_hdr *)(mtod(m, uint8_t *) + off);
1257
1258 /*
1259 * Userland needs to see all of this traffic for implementing
1260 * the endpoint discovery portion of multicast routing.
1261 */
1262 switch (mld->mld_type) {
1263 case MLD_LISTENER_QUERY:
1264 icmp6_ifstat_inc(ifp, ifs6_in_mldquery);
1265 if (icmp6len == sizeof(struct mld_hdr)) {
1266 if (mld_v1_input_query(ifp, ip6, mld) != 0)
1267 return (0);
1268 } else if (icmp6len >= sizeof(struct mldv2_query)) {
1269 if (mld_v2_input_query(ifp, ip6, m,
1270 (struct mldv2_query *)mld, off, icmp6len) != 0)
1271 return (0);
1272 }
1273 break;
1274 case MLD_LISTENER_REPORT:
1275 icmp6_ifstat_inc(ifp, ifs6_in_mldreport);
1276 if (mld_v1_input_report(ifp, ip6, mld) != 0)
1277 return (0);
1278 break;
1279 case MLDV2_LISTENER_REPORT:
1280 icmp6_ifstat_inc(ifp, ifs6_in_mldreport);
1281 break;
1282 case MLD_LISTENER_DONE:
1283 icmp6_ifstat_inc(ifp, ifs6_in_mlddone);
1284 break;
1285 default:
1286 break;
1287 }
1288
1289 return (0);
1290 }
1291
1292 /*
1293 * Fast timeout handler (global).
1294 * VIMAGE: Timeout handlers are expected to service all vimages.
1295 */
1296 static struct callout mldfast_callout;
1297 static void
mld_fasttimo(void * arg __unused)1298 mld_fasttimo(void *arg __unused)
1299 {
1300 struct epoch_tracker et;
1301 struct in6_multi_head inmh;
1302 VNET_ITERATOR_DECL(vnet_iter);
1303
1304 SLIST_INIT(&inmh);
1305
1306 NET_EPOCH_ENTER(et);
1307 VNET_LIST_RLOCK_NOSLEEP();
1308 VNET_FOREACH(vnet_iter) {
1309 CURVNET_SET(vnet_iter);
1310 mld_fasttimo_vnet(&inmh);
1311 CURVNET_RESTORE();
1312 }
1313 VNET_LIST_RUNLOCK_NOSLEEP();
1314 NET_EPOCH_EXIT(et);
1315 in6m_release_list_deferred(&inmh);
1316
1317 callout_reset(&mldfast_callout, hz / MLD_FASTHZ, mld_fasttimo, NULL);
1318 }
1319
1320 /*
1321 * Fast timeout handler (per-vnet).
1322 *
1323 * VIMAGE: Assume caller has set up our curvnet.
1324 */
1325 static void
mld_fasttimo_vnet(struct in6_multi_head * inmh)1326 mld_fasttimo_vnet(struct in6_multi_head *inmh)
1327 {
1328 struct mbufq scq; /* State-change packets */
1329 struct mbufq qrq; /* Query response packets */
1330 struct ifnet *ifp;
1331 struct mld_ifsoftc *mli;
1332 struct ifmultiaddr *ifma;
1333 struct in6_multi *inm;
1334 int uri_fasthz;
1335
1336 uri_fasthz = 0;
1337
1338 /*
1339 * Quick check to see if any work needs to be done, in order to
1340 * minimize the overhead of fasttimo processing.
1341 * SMPng: XXX Unlocked reads.
1342 */
1343 if (!V_current_state_timers_running6 &&
1344 !V_interface_timers_running6 &&
1345 !V_state_change_timers_running6)
1346 return;
1347
1348 IN6_MULTI_LIST_LOCK();
1349 MLD_LOCK();
1350
1351 /*
1352 * MLDv2 General Query response timer processing.
1353 */
1354 if (V_interface_timers_running6) {
1355 CTR1(KTR_MLD, "%s: interface timers running", __func__);
1356
1357 V_interface_timers_running6 = 0;
1358 LIST_FOREACH(mli, &V_mli_head, mli_link) {
1359 if (mli->mli_v2_timer == 0) {
1360 /* Do nothing. */
1361 } else if (--mli->mli_v2_timer == 0) {
1362 mld_v2_dispatch_general_query(mli);
1363 } else {
1364 V_interface_timers_running6 = 1;
1365 }
1366 }
1367 }
1368
1369 if (!V_current_state_timers_running6 &&
1370 !V_state_change_timers_running6)
1371 goto out_locked;
1372
1373 V_current_state_timers_running6 = 0;
1374 V_state_change_timers_running6 = 0;
1375
1376 CTR1(KTR_MLD, "%s: state change timers running", __func__);
1377
1378 /*
1379 * MLD host report and state-change timer processing.
1380 * Note: Processing a v2 group timer may remove a node.
1381 */
1382 LIST_FOREACH(mli, &V_mli_head, mli_link) {
1383 ifp = mli->mli_ifp;
1384
1385 if (mli->mli_version == MLD_VERSION_2) {
1386 uri_fasthz = MLD_RANDOM_DELAY(mli->mli_uri *
1387 MLD_FASTHZ);
1388 mbufq_init(&qrq, MLD_MAX_G_GS_PACKETS);
1389 mbufq_init(&scq, MLD_MAX_STATE_CHANGE_PACKETS);
1390 }
1391
1392 IF_ADDR_WLOCK(ifp);
1393 CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
1394 inm = in6m_ifmultiaddr_get_inm(ifma);
1395 if (inm == NULL)
1396 continue;
1397 switch (mli->mli_version) {
1398 case MLD_VERSION_1:
1399 mld_v1_process_group_timer(inmh, inm);
1400 break;
1401 case MLD_VERSION_2:
1402 mld_v2_process_group_timers(inmh, &qrq,
1403 &scq, inm, uri_fasthz);
1404 break;
1405 }
1406 }
1407 IF_ADDR_WUNLOCK(ifp);
1408
1409 switch (mli->mli_version) {
1410 case MLD_VERSION_1:
1411 /*
1412 * Transmit reports for this lifecycle. This
1413 * is done while not holding IF_ADDR_LOCK
1414 * since this can call
1415 * in6ifa_ifpforlinklocal() which locks
1416 * IF_ADDR_LOCK internally as well as
1417 * ip6_output() to transmit a packet.
1418 */
1419 while ((inm = SLIST_FIRST(inmh)) != NULL) {
1420 SLIST_REMOVE_HEAD(inmh, in6m_defer);
1421 (void)mld_v1_transmit_report(inm,
1422 MLD_LISTENER_REPORT);
1423 }
1424 break;
1425 case MLD_VERSION_2:
1426 mld_dispatch_queue(&qrq, 0);
1427 mld_dispatch_queue(&scq, 0);
1428 break;
1429 }
1430 }
1431
1432 out_locked:
1433 MLD_UNLOCK();
1434 IN6_MULTI_LIST_UNLOCK();
1435 }
1436
1437 /*
1438 * Update host report group timer.
1439 * Will update the global pending timer flags.
1440 */
1441 static void
mld_v1_process_group_timer(struct in6_multi_head * inmh,struct in6_multi * inm)1442 mld_v1_process_group_timer(struct in6_multi_head *inmh, struct in6_multi *inm)
1443 {
1444 int report_timer_expired;
1445
1446 IN6_MULTI_LIST_LOCK_ASSERT();
1447 MLD_LOCK_ASSERT();
1448
1449 if (inm->in6m_timer == 0) {
1450 report_timer_expired = 0;
1451 } else if (--inm->in6m_timer == 0) {
1452 report_timer_expired = 1;
1453 } else {
1454 V_current_state_timers_running6 = 1;
1455 return;
1456 }
1457
1458 switch (inm->in6m_state) {
1459 case MLD_NOT_MEMBER:
1460 case MLD_SILENT_MEMBER:
1461 case MLD_IDLE_MEMBER:
1462 case MLD_LAZY_MEMBER:
1463 case MLD_SLEEPING_MEMBER:
1464 case MLD_AWAKENING_MEMBER:
1465 break;
1466 case MLD_REPORTING_MEMBER:
1467 if (report_timer_expired) {
1468 inm->in6m_state = MLD_IDLE_MEMBER;
1469 SLIST_INSERT_HEAD(inmh, inm, in6m_defer);
1470 }
1471 break;
1472 case MLD_G_QUERY_PENDING_MEMBER:
1473 case MLD_SG_QUERY_PENDING_MEMBER:
1474 case MLD_LEAVING_MEMBER:
1475 break;
1476 }
1477 }
1478
1479 /*
1480 * Update a group's timers for MLDv2.
1481 * Will update the global pending timer flags.
1482 * Note: Unlocked read from mli.
1483 */
1484 static void
mld_v2_process_group_timers(struct in6_multi_head * inmh,struct mbufq * qrq,struct mbufq * scq,struct in6_multi * inm,const int uri_fasthz)1485 mld_v2_process_group_timers(struct in6_multi_head *inmh,
1486 struct mbufq *qrq, struct mbufq *scq,
1487 struct in6_multi *inm, const int uri_fasthz)
1488 {
1489 int query_response_timer_expired;
1490 int state_change_retransmit_timer_expired;
1491 #ifdef KTR
1492 char ip6tbuf[INET6_ADDRSTRLEN];
1493 #endif
1494
1495 IN6_MULTI_LIST_LOCK_ASSERT();
1496 MLD_LOCK_ASSERT();
1497
1498 query_response_timer_expired = 0;
1499 state_change_retransmit_timer_expired = 0;
1500
1501 /*
1502 * During a transition from compatibility mode back to MLDv2,
1503 * a group record in REPORTING state may still have its group
1504 * timer active. This is a no-op in this function; it is easier
1505 * to deal with it here than to complicate the slow-timeout path.
1506 */
1507 if (inm->in6m_timer == 0) {
1508 query_response_timer_expired = 0;
1509 } else if (--inm->in6m_timer == 0) {
1510 query_response_timer_expired = 1;
1511 } else {
1512 V_current_state_timers_running6 = 1;
1513 }
1514
1515 if (inm->in6m_sctimer == 0) {
1516 state_change_retransmit_timer_expired = 0;
1517 } else if (--inm->in6m_sctimer == 0) {
1518 state_change_retransmit_timer_expired = 1;
1519 } else {
1520 V_state_change_timers_running6 = 1;
1521 }
1522
1523 /* We are in fasttimo, so be quick about it. */
1524 if (!state_change_retransmit_timer_expired &&
1525 !query_response_timer_expired)
1526 return;
1527
1528 switch (inm->in6m_state) {
1529 case MLD_NOT_MEMBER:
1530 case MLD_SILENT_MEMBER:
1531 case MLD_SLEEPING_MEMBER:
1532 case MLD_LAZY_MEMBER:
1533 case MLD_AWAKENING_MEMBER:
1534 case MLD_IDLE_MEMBER:
1535 break;
1536 case MLD_G_QUERY_PENDING_MEMBER:
1537 case MLD_SG_QUERY_PENDING_MEMBER:
1538 /*
1539 * Respond to a previously pending Group-Specific
1540 * or Group-and-Source-Specific query by enqueueing
1541 * the appropriate Current-State report for
1542 * immediate transmission.
1543 */
1544 if (query_response_timer_expired) {
1545 int retval __unused;
1546
1547 retval = mld_v2_enqueue_group_record(qrq, inm, 0, 1,
1548 (inm->in6m_state == MLD_SG_QUERY_PENDING_MEMBER),
1549 0);
1550 CTR2(KTR_MLD, "%s: enqueue record = %d",
1551 __func__, retval);
1552 inm->in6m_state = MLD_REPORTING_MEMBER;
1553 in6m_clear_recorded(inm);
1554 }
1555 /* FALLTHROUGH */
1556 case MLD_REPORTING_MEMBER:
1557 case MLD_LEAVING_MEMBER:
1558 if (state_change_retransmit_timer_expired) {
1559 /*
1560 * State-change retransmission timer fired.
1561 * If there are any further pending retransmissions,
1562 * set the global pending state-change flag, and
1563 * reset the timer.
1564 */
1565 if (--inm->in6m_scrv > 0) {
1566 inm->in6m_sctimer = uri_fasthz;
1567 V_state_change_timers_running6 = 1;
1568 }
1569 /*
1570 * Retransmit the previously computed state-change
1571 * report. If there are no further pending
1572 * retransmissions, the mbuf queue will be consumed.
1573 * Update T0 state to T1 as we have now sent
1574 * a state-change.
1575 */
1576 (void)mld_v2_merge_state_changes(inm, scq);
1577
1578 in6m_commit(inm);
1579 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
1580 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
1581 if_name(inm->in6m_ifp));
1582
1583 /*
1584 * If we are leaving the group for good, make sure
1585 * we release MLD's reference to it.
1586 * This release must be deferred using a SLIST,
1587 * as we are called from a loop which traverses
1588 * the in_ifmultiaddr TAILQ.
1589 */
1590 if (inm->in6m_state == MLD_LEAVING_MEMBER &&
1591 inm->in6m_scrv == 0) {
1592 inm->in6m_state = MLD_NOT_MEMBER;
1593 in6m_disconnect_locked(inmh, inm);
1594 in6m_rele_locked(inmh, inm);
1595 }
1596 }
1597 break;
1598 }
1599 }
1600
1601 /*
1602 * Switch to a different version on the given interface,
1603 * as per Section 9.12.
1604 */
1605 static void
mld_set_version(struct mld_ifsoftc * mli,const int version)1606 mld_set_version(struct mld_ifsoftc *mli, const int version)
1607 {
1608 int old_version_timer;
1609
1610 MLD_LOCK_ASSERT();
1611
1612 CTR4(KTR_MLD, "%s: switching to v%d on ifp %p(%s)", __func__,
1613 version, mli->mli_ifp, if_name(mli->mli_ifp));
1614
1615 if (version == MLD_VERSION_1) {
1616 /*
1617 * Compute the "Older Version Querier Present" timer as per
1618 * Section 9.12.
1619 */
1620 old_version_timer = (mli->mli_rv * mli->mli_qi) + mli->mli_qri;
1621 old_version_timer *= MLD_SLOWHZ;
1622 mli->mli_v1_timer = old_version_timer;
1623 }
1624
1625 if (mli->mli_v1_timer > 0 && mli->mli_version != MLD_VERSION_1) {
1626 mli->mli_version = MLD_VERSION_1;
1627 mld_v2_cancel_link_timers(mli);
1628 }
1629 }
1630
1631 /*
1632 * Cancel pending MLDv2 timers for the given link and all groups
1633 * joined on it; state-change, general-query, and group-query timers.
1634 */
1635 static void
mld_v2_cancel_link_timers(struct mld_ifsoftc * mli)1636 mld_v2_cancel_link_timers(struct mld_ifsoftc *mli)
1637 {
1638 struct epoch_tracker et;
1639 struct in6_multi_head inmh;
1640 struct ifmultiaddr *ifma;
1641 struct ifnet *ifp;
1642 struct in6_multi *inm;
1643
1644 CTR3(KTR_MLD, "%s: cancel v2 timers on ifp %p(%s)", __func__,
1645 mli->mli_ifp, if_name(mli->mli_ifp));
1646
1647 SLIST_INIT(&inmh);
1648 IN6_MULTI_LIST_LOCK_ASSERT();
1649 MLD_LOCK_ASSERT();
1650
1651 /*
1652 * Fast-track this potentially expensive operation
1653 * by checking all the global 'timer pending' flags.
1654 */
1655 if (!V_interface_timers_running6 &&
1656 !V_state_change_timers_running6 &&
1657 !V_current_state_timers_running6)
1658 return;
1659
1660 mli->mli_v2_timer = 0;
1661
1662 ifp = mli->mli_ifp;
1663
1664 IF_ADDR_WLOCK(ifp);
1665 NET_EPOCH_ENTER(et);
1666 CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
1667 inm = in6m_ifmultiaddr_get_inm(ifma);
1668 if (inm == NULL)
1669 continue;
1670 switch (inm->in6m_state) {
1671 case MLD_NOT_MEMBER:
1672 case MLD_SILENT_MEMBER:
1673 case MLD_IDLE_MEMBER:
1674 case MLD_LAZY_MEMBER:
1675 case MLD_SLEEPING_MEMBER:
1676 case MLD_AWAKENING_MEMBER:
1677 break;
1678 case MLD_LEAVING_MEMBER:
1679 /*
1680 * If we are leaving the group and switching
1681 * version, we need to release the final
1682 * reference held for issuing the INCLUDE {}.
1683 */
1684 if (inm->in6m_refcount == 1)
1685 in6m_disconnect_locked(&inmh, inm);
1686 in6m_rele_locked(&inmh, inm);
1687 /* FALLTHROUGH */
1688 case MLD_G_QUERY_PENDING_MEMBER:
1689 case MLD_SG_QUERY_PENDING_MEMBER:
1690 in6m_clear_recorded(inm);
1691 /* FALLTHROUGH */
1692 case MLD_REPORTING_MEMBER:
1693 inm->in6m_sctimer = 0;
1694 inm->in6m_timer = 0;
1695 inm->in6m_state = MLD_REPORTING_MEMBER;
1696 /*
1697 * Free any pending MLDv2 state-change records.
1698 */
1699 mbufq_drain(&inm->in6m_scq);
1700 break;
1701 }
1702 }
1703 NET_EPOCH_EXIT(et);
1704 IF_ADDR_WUNLOCK(ifp);
1705 in6m_release_list_deferred(&inmh);
1706 }
1707
1708 /*
1709 * Global slowtimo handler.
1710 * VIMAGE: Timeout handlers are expected to service all vimages.
1711 */
1712 static struct callout mldslow_callout;
1713 static void
mld_slowtimo(void * arg __unused)1714 mld_slowtimo(void *arg __unused)
1715 {
1716 VNET_ITERATOR_DECL(vnet_iter);
1717
1718 VNET_LIST_RLOCK_NOSLEEP();
1719 VNET_FOREACH(vnet_iter) {
1720 CURVNET_SET(vnet_iter);
1721 mld_slowtimo_vnet();
1722 CURVNET_RESTORE();
1723 }
1724 VNET_LIST_RUNLOCK_NOSLEEP();
1725
1726 callout_reset(&mldslow_callout, hz / MLD_SLOWHZ, mld_slowtimo, NULL);
1727 }
1728
1729 /*
1730 * Per-vnet slowtimo handler.
1731 */
1732 static void
mld_slowtimo_vnet(void)1733 mld_slowtimo_vnet(void)
1734 {
1735 struct mld_ifsoftc *mli;
1736
1737 MLD_LOCK();
1738
1739 LIST_FOREACH(mli, &V_mli_head, mli_link) {
1740 mld_v1_process_querier_timers(mli);
1741 }
1742
1743 MLD_UNLOCK();
1744 }
1745
1746 /*
1747 * Update the Older Version Querier Present timers for a link.
1748 * See Section 9.12 of RFC 3810.
1749 */
1750 static void
mld_v1_process_querier_timers(struct mld_ifsoftc * mli)1751 mld_v1_process_querier_timers(struct mld_ifsoftc *mli)
1752 {
1753
1754 MLD_LOCK_ASSERT();
1755
1756 if (mli->mli_version != MLD_VERSION_2 && --mli->mli_v1_timer == 0) {
1757 /*
1758 * MLDv1 Querier Present timer expired; revert to MLDv2.
1759 */
1760 CTR5(KTR_MLD,
1761 "%s: transition from v%d -> v%d on %p(%s)",
1762 __func__, mli->mli_version, MLD_VERSION_2,
1763 mli->mli_ifp, if_name(mli->mli_ifp));
1764 mli->mli_version = MLD_VERSION_2;
1765 }
1766 }
1767
1768 /*
1769 * Transmit an MLDv1 report immediately.
1770 */
1771 static int
mld_v1_transmit_report(struct in6_multi * in6m,const int type)1772 mld_v1_transmit_report(struct in6_multi *in6m, const int type)
1773 {
1774 struct ifnet *ifp;
1775 struct in6_ifaddr *ia;
1776 struct ip6_hdr *ip6;
1777 struct mbuf *mh, *md;
1778 struct mld_hdr *mld;
1779
1780 NET_EPOCH_ASSERT();
1781 IN6_MULTI_LIST_LOCK_ASSERT();
1782 MLD_LOCK_ASSERT();
1783
1784 ifp = in6m->in6m_ifp;
1785 /* in process of being freed */
1786 if (ifp == NULL)
1787 return (0);
1788 ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
1789 /* ia may be NULL if link-local address is tentative. */
1790
1791 mh = m_gethdr(M_NOWAIT, MT_DATA);
1792 if (mh == NULL) {
1793 if (ia != NULL)
1794 ifa_free(&ia->ia_ifa);
1795 return (ENOMEM);
1796 }
1797 md = m_get(M_NOWAIT, MT_DATA);
1798 if (md == NULL) {
1799 m_free(mh);
1800 if (ia != NULL)
1801 ifa_free(&ia->ia_ifa);
1802 return (ENOMEM);
1803 }
1804 mh->m_next = md;
1805
1806 /*
1807 * FUTURE: Consider increasing alignment by ETHER_HDR_LEN, so
1808 * that ether_output() does not need to allocate another mbuf
1809 * for the header in the most common case.
1810 */
1811 M_ALIGN(mh, sizeof(struct ip6_hdr));
1812 mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld_hdr);
1813 mh->m_len = sizeof(struct ip6_hdr);
1814
1815 ip6 = mtod(mh, struct ip6_hdr *);
1816 ip6->ip6_flow = 0;
1817 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
1818 ip6->ip6_vfc |= IPV6_VERSION;
1819 ip6->ip6_nxt = IPPROTO_ICMPV6;
1820 ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any;
1821 ip6->ip6_dst = in6m->in6m_addr;
1822
1823 md->m_len = sizeof(struct mld_hdr);
1824 mld = mtod(md, struct mld_hdr *);
1825 mld->mld_type = type;
1826 mld->mld_code = 0;
1827 mld->mld_cksum = 0;
1828 mld->mld_maxdelay = 0;
1829 mld->mld_reserved = 0;
1830 mld->mld_addr = in6m->in6m_addr;
1831 in6_clearscope(&mld->mld_addr);
1832 mld->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6,
1833 sizeof(struct ip6_hdr), sizeof(struct mld_hdr));
1834
1835 mld_save_context(mh, ifp);
1836 mh->m_flags |= M_MLDV1;
1837
1838 mld_dispatch_packet(mh);
1839
1840 if (ia != NULL)
1841 ifa_free(&ia->ia_ifa);
1842 return (0);
1843 }
1844
1845 /*
1846 * Process a state change from the upper layer for the given IPv6 group.
1847 *
1848 * Each socket holds a reference on the in_multi in its own ip_moptions.
1849 * The socket layer will have made the necessary updates to.the group
1850 * state, it is now up to MLD to issue a state change report if there
1851 * has been any change between T0 (when the last state-change was issued)
1852 * and T1 (now).
1853 *
1854 * We use the MLDv2 state machine at group level. The MLd module
1855 * however makes the decision as to which MLD protocol version to speak.
1856 * A state change *from* INCLUDE {} always means an initial join.
1857 * A state change *to* INCLUDE {} always means a final leave.
1858 *
1859 * If delay is non-zero, and the state change is an initial multicast
1860 * join, the state change report will be delayed by 'delay' ticks
1861 * in units of MLD_FASTHZ if MLDv1 is active on the link; otherwise
1862 * the initial MLDv2 state change report will be delayed by whichever
1863 * is sooner, a pending state-change timer or delay itself.
1864 *
1865 * VIMAGE: curvnet should have been set by caller, as this routine
1866 * is called from the socket option handlers.
1867 */
1868 int
mld_change_state(struct in6_multi * inm,const int delay)1869 mld_change_state(struct in6_multi *inm, const int delay)
1870 {
1871 struct mld_ifsoftc *mli;
1872 struct ifnet *ifp;
1873 int error;
1874
1875 IN6_MULTI_LIST_LOCK_ASSERT();
1876
1877 error = 0;
1878
1879 /*
1880 * Check if the in6_multi has already been disconnected.
1881 */
1882 if (inm->in6m_ifp == NULL) {
1883 CTR1(KTR_MLD, "%s: inm is disconnected", __func__);
1884 return (0);
1885 }
1886
1887 /*
1888 * Try to detect if the upper layer just asked us to change state
1889 * for an interface which has now gone away.
1890 */
1891 KASSERT(inm->in6m_ifma != NULL, ("%s: no ifma", __func__));
1892 ifp = inm->in6m_ifma->ifma_ifp;
1893 if (ifp == NULL)
1894 return (0);
1895 /*
1896 * Sanity check that netinet6's notion of ifp is the
1897 * same as net's.
1898 */
1899 KASSERT(inm->in6m_ifp == ifp, ("%s: bad ifp", __func__));
1900
1901 MLD_LOCK();
1902 mli = MLD_IFINFO(ifp);
1903 KASSERT(mli != NULL, ("%s: no mld_ifsoftc for ifp %p", __func__, ifp));
1904
1905 /*
1906 * If we detect a state transition to or from MCAST_UNDEFINED
1907 * for this group, then we are starting or finishing an MLD
1908 * life cycle for this group.
1909 */
1910 if (inm->in6m_st[1].iss_fmode != inm->in6m_st[0].iss_fmode) {
1911 CTR3(KTR_MLD, "%s: inm transition %d -> %d", __func__,
1912 inm->in6m_st[0].iss_fmode, inm->in6m_st[1].iss_fmode);
1913 if (inm->in6m_st[0].iss_fmode == MCAST_UNDEFINED) {
1914 CTR1(KTR_MLD, "%s: initial join", __func__);
1915 error = mld_initial_join(inm, mli, delay);
1916 goto out_locked;
1917 } else if (inm->in6m_st[1].iss_fmode == MCAST_UNDEFINED) {
1918 CTR1(KTR_MLD, "%s: final leave", __func__);
1919 mld_final_leave(inm, mli);
1920 goto out_locked;
1921 }
1922 } else {
1923 CTR1(KTR_MLD, "%s: filter set change", __func__);
1924 }
1925
1926 error = mld_handle_state_change(inm, mli);
1927
1928 out_locked:
1929 MLD_UNLOCK();
1930 return (error);
1931 }
1932
1933 /*
1934 * Perform the initial join for an MLD group.
1935 *
1936 * When joining a group:
1937 * If the group should have its MLD traffic suppressed, do nothing.
1938 * MLDv1 starts sending MLDv1 host membership reports.
1939 * MLDv2 will schedule an MLDv2 state-change report containing the
1940 * initial state of the membership.
1941 *
1942 * If the delay argument is non-zero, then we must delay sending the
1943 * initial state change for delay ticks (in units of MLD_FASTHZ).
1944 */
1945 static int
mld_initial_join(struct in6_multi * inm,struct mld_ifsoftc * mli,const int delay)1946 mld_initial_join(struct in6_multi *inm, struct mld_ifsoftc *mli,
1947 const int delay)
1948 {
1949 struct epoch_tracker et;
1950 struct ifnet *ifp;
1951 struct mbufq *mq;
1952 int error, retval, syncstates;
1953 int odelay;
1954 #ifdef KTR
1955 char ip6tbuf[INET6_ADDRSTRLEN];
1956 #endif
1957
1958 CTR4(KTR_MLD, "%s: initial join %s on ifp %p(%s)",
1959 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
1960 inm->in6m_ifp, if_name(inm->in6m_ifp));
1961
1962 error = 0;
1963 syncstates = 1;
1964
1965 ifp = inm->in6m_ifp;
1966
1967 IN6_MULTI_LIST_LOCK_ASSERT();
1968 MLD_LOCK_ASSERT();
1969
1970 KASSERT(mli && mli->mli_ifp == ifp, ("%s: inconsistent ifp", __func__));
1971
1972 /*
1973 * Groups joined on loopback or marked as 'not reported',
1974 * enter the MLD_SILENT_MEMBER state and
1975 * are never reported in any protocol exchanges.
1976 * All other groups enter the appropriate state machine
1977 * for the version in use on this link.
1978 * A link marked as MLIF_SILENT causes MLD to be completely
1979 * disabled for the link.
1980 */
1981 if ((ifp->if_flags & IFF_LOOPBACK) ||
1982 (mli->mli_flags & MLIF_SILENT) ||
1983 !mld_is_addr_reported(&inm->in6m_addr)) {
1984 CTR1(KTR_MLD,
1985 "%s: not kicking state machine for silent group", __func__);
1986 inm->in6m_state = MLD_SILENT_MEMBER;
1987 inm->in6m_timer = 0;
1988 } else {
1989 /*
1990 * Deal with overlapping in_multi lifecycle.
1991 * If this group was LEAVING, then make sure
1992 * we drop the reference we picked up to keep the
1993 * group around for the final INCLUDE {} enqueue.
1994 */
1995 if (mli->mli_version == MLD_VERSION_2 &&
1996 inm->in6m_state == MLD_LEAVING_MEMBER) {
1997 inm->in6m_refcount--;
1998 MPASS(inm->in6m_refcount > 0);
1999 }
2000 inm->in6m_state = MLD_REPORTING_MEMBER;
2001
2002 switch (mli->mli_version) {
2003 case MLD_VERSION_1:
2004 /*
2005 * If a delay was provided, only use it if
2006 * it is greater than the delay normally
2007 * used for an MLDv1 state change report,
2008 * and delay sending the initial MLDv1 report
2009 * by not transitioning to the IDLE state.
2010 */
2011 odelay = MLD_RANDOM_DELAY(MLD_V1_MAX_RI * MLD_FASTHZ);
2012 if (delay) {
2013 inm->in6m_timer = max(delay, odelay);
2014 V_current_state_timers_running6 = 1;
2015 } else {
2016 inm->in6m_state = MLD_IDLE_MEMBER;
2017 NET_EPOCH_ENTER(et);
2018 error = mld_v1_transmit_report(inm,
2019 MLD_LISTENER_REPORT);
2020 NET_EPOCH_EXIT(et);
2021 if (error == 0) {
2022 inm->in6m_timer = odelay;
2023 V_current_state_timers_running6 = 1;
2024 }
2025 }
2026 break;
2027
2028 case MLD_VERSION_2:
2029 /*
2030 * Defer update of T0 to T1, until the first copy
2031 * of the state change has been transmitted.
2032 */
2033 syncstates = 0;
2034
2035 /*
2036 * Immediately enqueue a State-Change Report for
2037 * this interface, freeing any previous reports.
2038 * Don't kick the timers if there is nothing to do,
2039 * or if an error occurred.
2040 */
2041 mq = &inm->in6m_scq;
2042 mbufq_drain(mq);
2043 retval = mld_v2_enqueue_group_record(mq, inm, 1,
2044 0, 0, (mli->mli_flags & MLIF_USEALLOW));
2045 CTR2(KTR_MLD, "%s: enqueue record = %d",
2046 __func__, retval);
2047 if (retval <= 0) {
2048 error = retval * -1;
2049 break;
2050 }
2051
2052 /*
2053 * Schedule transmission of pending state-change
2054 * report up to RV times for this link. The timer
2055 * will fire at the next mld_fasttimo (~200ms),
2056 * giving us an opportunity to merge the reports.
2057 *
2058 * If a delay was provided to this function, only
2059 * use this delay if sooner than the existing one.
2060 */
2061 KASSERT(mli->mli_rv > 1,
2062 ("%s: invalid robustness %d", __func__,
2063 mli->mli_rv));
2064 inm->in6m_scrv = mli->mli_rv;
2065 if (delay) {
2066 if (inm->in6m_sctimer > 1) {
2067 inm->in6m_sctimer =
2068 min(inm->in6m_sctimer, delay);
2069 } else
2070 inm->in6m_sctimer = delay;
2071 } else
2072 inm->in6m_sctimer = 1;
2073 V_state_change_timers_running6 = 1;
2074
2075 error = 0;
2076 break;
2077 }
2078 }
2079
2080 /*
2081 * Only update the T0 state if state change is atomic,
2082 * i.e. we don't need to wait for a timer to fire before we
2083 * can consider the state change to have been communicated.
2084 */
2085 if (syncstates) {
2086 in6m_commit(inm);
2087 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
2088 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2089 if_name(inm->in6m_ifp));
2090 }
2091
2092 return (error);
2093 }
2094
2095 /*
2096 * Issue an intermediate state change during the life-cycle.
2097 */
2098 static int
mld_handle_state_change(struct in6_multi * inm,struct mld_ifsoftc * mli)2099 mld_handle_state_change(struct in6_multi *inm, struct mld_ifsoftc *mli)
2100 {
2101 struct ifnet *ifp;
2102 int retval;
2103 #ifdef KTR
2104 char ip6tbuf[INET6_ADDRSTRLEN];
2105 #endif
2106
2107 CTR4(KTR_MLD, "%s: state change for %s on ifp %p(%s)",
2108 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2109 inm->in6m_ifp, if_name(inm->in6m_ifp));
2110
2111 ifp = inm->in6m_ifp;
2112
2113 IN6_MULTI_LIST_LOCK_ASSERT();
2114 MLD_LOCK_ASSERT();
2115
2116 KASSERT(mli && mli->mli_ifp == ifp,
2117 ("%s: inconsistent ifp", __func__));
2118
2119 if ((ifp->if_flags & IFF_LOOPBACK) ||
2120 (mli->mli_flags & MLIF_SILENT) ||
2121 !mld_is_addr_reported(&inm->in6m_addr) ||
2122 (mli->mli_version != MLD_VERSION_2)) {
2123 if (!mld_is_addr_reported(&inm->in6m_addr)) {
2124 CTR1(KTR_MLD,
2125 "%s: not kicking state machine for silent group", __func__);
2126 }
2127 CTR1(KTR_MLD, "%s: nothing to do", __func__);
2128 in6m_commit(inm);
2129 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
2130 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2131 if_name(inm->in6m_ifp));
2132 return (0);
2133 }
2134
2135 mbufq_drain(&inm->in6m_scq);
2136
2137 retval = mld_v2_enqueue_group_record(&inm->in6m_scq, inm, 1, 0, 0,
2138 (mli->mli_flags & MLIF_USEALLOW));
2139 CTR2(KTR_MLD, "%s: enqueue record = %d", __func__, retval);
2140 if (retval <= 0)
2141 return (-retval);
2142
2143 /*
2144 * If record(s) were enqueued, start the state-change
2145 * report timer for this group.
2146 */
2147 inm->in6m_scrv = mli->mli_rv;
2148 inm->in6m_sctimer = 1;
2149 V_state_change_timers_running6 = 1;
2150
2151 return (0);
2152 }
2153
2154 /*
2155 * Perform the final leave for a multicast address.
2156 *
2157 * When leaving a group:
2158 * MLDv1 sends a DONE message, if and only if we are the reporter.
2159 * MLDv2 enqueues a state-change report containing a transition
2160 * to INCLUDE {} for immediate transmission.
2161 */
2162 static void
mld_final_leave(struct in6_multi * inm,struct mld_ifsoftc * mli)2163 mld_final_leave(struct in6_multi *inm, struct mld_ifsoftc *mli)
2164 {
2165 struct epoch_tracker et;
2166 #ifdef KTR
2167 char ip6tbuf[INET6_ADDRSTRLEN];
2168 #endif
2169
2170 CTR4(KTR_MLD, "%s: final leave %s on ifp %p(%s)",
2171 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2172 inm->in6m_ifp, if_name(inm->in6m_ifp));
2173
2174 IN6_MULTI_LIST_LOCK_ASSERT();
2175 MLD_LOCK_ASSERT();
2176
2177 switch (inm->in6m_state) {
2178 case MLD_NOT_MEMBER:
2179 case MLD_SILENT_MEMBER:
2180 case MLD_LEAVING_MEMBER:
2181 /* Already leaving or left; do nothing. */
2182 CTR1(KTR_MLD,
2183 "%s: not kicking state machine for silent group", __func__);
2184 break;
2185 case MLD_REPORTING_MEMBER:
2186 case MLD_IDLE_MEMBER:
2187 case MLD_G_QUERY_PENDING_MEMBER:
2188 case MLD_SG_QUERY_PENDING_MEMBER:
2189 if (mli->mli_version == MLD_VERSION_1) {
2190 #ifdef INVARIANTS
2191 if (inm->in6m_state == MLD_G_QUERY_PENDING_MEMBER ||
2192 inm->in6m_state == MLD_SG_QUERY_PENDING_MEMBER)
2193 panic("%s: MLDv2 state reached, not MLDv2 mode",
2194 __func__);
2195 #endif
2196 NET_EPOCH_ENTER(et);
2197 mld_v1_transmit_report(inm, MLD_LISTENER_DONE);
2198 NET_EPOCH_EXIT(et);
2199 inm->in6m_state = MLD_NOT_MEMBER;
2200 V_current_state_timers_running6 = 1;
2201 } else if (mli->mli_version == MLD_VERSION_2) {
2202 /*
2203 * Stop group timer and all pending reports.
2204 * Immediately enqueue a state-change report
2205 * TO_IN {} to be sent on the next fast timeout,
2206 * giving us an opportunity to merge reports.
2207 */
2208 mbufq_drain(&inm->in6m_scq);
2209 inm->in6m_timer = 0;
2210 inm->in6m_scrv = mli->mli_rv;
2211 CTR4(KTR_MLD, "%s: Leaving %s/%s with %d "
2212 "pending retransmissions.", __func__,
2213 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2214 if_name(inm->in6m_ifp), inm->in6m_scrv);
2215 if (inm->in6m_scrv == 0) {
2216 inm->in6m_state = MLD_NOT_MEMBER;
2217 inm->in6m_sctimer = 0;
2218 } else {
2219 int retval __diagused;
2220
2221 in6m_acquire_locked(inm);
2222
2223 retval = mld_v2_enqueue_group_record(
2224 &inm->in6m_scq, inm, 1, 0, 0,
2225 (mli->mli_flags & MLIF_USEALLOW));
2226 KASSERT(retval != 0,
2227 ("%s: enqueue record = %d", __func__,
2228 retval));
2229
2230 inm->in6m_state = MLD_LEAVING_MEMBER;
2231 inm->in6m_sctimer = 1;
2232 V_state_change_timers_running6 = 1;
2233 }
2234 break;
2235 }
2236 break;
2237 case MLD_LAZY_MEMBER:
2238 case MLD_SLEEPING_MEMBER:
2239 case MLD_AWAKENING_MEMBER:
2240 /* Our reports are suppressed; do nothing. */
2241 break;
2242 }
2243
2244 in6m_commit(inm);
2245 CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
2246 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2247 if_name(inm->in6m_ifp));
2248 inm->in6m_st[1].iss_fmode = MCAST_UNDEFINED;
2249 CTR3(KTR_MLD, "%s: T1 now MCAST_UNDEFINED for %p/%s",
2250 __func__, &inm->in6m_addr, if_name(inm->in6m_ifp));
2251 }
2252
2253 /*
2254 * Enqueue an MLDv2 group record to the given output queue.
2255 *
2256 * If is_state_change is zero, a current-state record is appended.
2257 * If is_state_change is non-zero, a state-change report is appended.
2258 *
2259 * If is_group_query is non-zero, an mbuf packet chain is allocated.
2260 * If is_group_query is zero, and if there is a packet with free space
2261 * at the tail of the queue, it will be appended to providing there
2262 * is enough free space.
2263 * Otherwise a new mbuf packet chain is allocated.
2264 *
2265 * If is_source_query is non-zero, each source is checked to see if
2266 * it was recorded for a Group-Source query, and will be omitted if
2267 * it is not both in-mode and recorded.
2268 *
2269 * If use_block_allow is non-zero, state change reports for initial join
2270 * and final leave, on an inclusive mode group with a source list, will be
2271 * rewritten to use the ALLOW_NEW and BLOCK_OLD record types, respectively.
2272 *
2273 * The function will attempt to allocate leading space in the packet
2274 * for the IPv6+ICMP headers to be prepended without fragmenting the chain.
2275 *
2276 * If successful the size of all data appended to the queue is returned,
2277 * otherwise an error code less than zero is returned, or zero if
2278 * no record(s) were appended.
2279 */
2280 static int
mld_v2_enqueue_group_record(struct mbufq * mq,struct in6_multi * inm,const int is_state_change,const int is_group_query,const int is_source_query,const int use_block_allow)2281 mld_v2_enqueue_group_record(struct mbufq *mq, struct in6_multi *inm,
2282 const int is_state_change, const int is_group_query,
2283 const int is_source_query, const int use_block_allow)
2284 {
2285 struct mldv2_record mr;
2286 struct mldv2_record *pmr;
2287 struct ifnet *ifp;
2288 struct ip6_msource *ims, *nims;
2289 struct mbuf *m0, *m, *md;
2290 int is_filter_list_change;
2291 int minrec0len, m0srcs, msrcs, nbytes, off;
2292 int record_has_sources;
2293 int now;
2294 int type;
2295 uint8_t mode;
2296 #ifdef KTR
2297 char ip6tbuf[INET6_ADDRSTRLEN];
2298 #endif
2299
2300 IN6_MULTI_LIST_LOCK_ASSERT();
2301
2302 ifp = inm->in6m_ifp;
2303 is_filter_list_change = 0;
2304 m = NULL;
2305 m0 = NULL;
2306 m0srcs = 0;
2307 msrcs = 0;
2308 nbytes = 0;
2309 nims = NULL;
2310 record_has_sources = 1;
2311 pmr = NULL;
2312 type = MLD_DO_NOTHING;
2313 mode = inm->in6m_st[1].iss_fmode;
2314
2315 /*
2316 * If we did not transition out of ASM mode during t0->t1,
2317 * and there are no source nodes to process, we can skip
2318 * the generation of source records.
2319 */
2320 if (inm->in6m_st[0].iss_asm > 0 && inm->in6m_st[1].iss_asm > 0 &&
2321 inm->in6m_nsrc == 0)
2322 record_has_sources = 0;
2323
2324 if (is_state_change) {
2325 /*
2326 * Queue a state change record.
2327 * If the mode did not change, and there are non-ASM
2328 * listeners or source filters present,
2329 * we potentially need to issue two records for the group.
2330 * If there are ASM listeners, and there was no filter
2331 * mode transition of any kind, do nothing.
2332 *
2333 * If we are transitioning to MCAST_UNDEFINED, we need
2334 * not send any sources. A transition to/from this state is
2335 * considered inclusive with some special treatment.
2336 *
2337 * If we are rewriting initial joins/leaves to use
2338 * ALLOW/BLOCK, and the group's membership is inclusive,
2339 * we need to send sources in all cases.
2340 */
2341 if (mode != inm->in6m_st[0].iss_fmode) {
2342 if (mode == MCAST_EXCLUDE) {
2343 CTR1(KTR_MLD, "%s: change to EXCLUDE",
2344 __func__);
2345 type = MLD_CHANGE_TO_EXCLUDE_MODE;
2346 } else {
2347 CTR1(KTR_MLD, "%s: change to INCLUDE",
2348 __func__);
2349 if (use_block_allow) {
2350 /*
2351 * XXX
2352 * Here we're interested in state
2353 * edges either direction between
2354 * MCAST_UNDEFINED and MCAST_INCLUDE.
2355 * Perhaps we should just check
2356 * the group state, rather than
2357 * the filter mode.
2358 */
2359 if (mode == MCAST_UNDEFINED) {
2360 type = MLD_BLOCK_OLD_SOURCES;
2361 } else {
2362 type = MLD_ALLOW_NEW_SOURCES;
2363 }
2364 } else {
2365 type = MLD_CHANGE_TO_INCLUDE_MODE;
2366 if (mode == MCAST_UNDEFINED)
2367 record_has_sources = 0;
2368 }
2369 }
2370 } else {
2371 if (record_has_sources) {
2372 is_filter_list_change = 1;
2373 } else {
2374 type = MLD_DO_NOTHING;
2375 }
2376 }
2377 } else {
2378 /*
2379 * Queue a current state record.
2380 */
2381 if (mode == MCAST_EXCLUDE) {
2382 type = MLD_MODE_IS_EXCLUDE;
2383 } else if (mode == MCAST_INCLUDE) {
2384 type = MLD_MODE_IS_INCLUDE;
2385 KASSERT(inm->in6m_st[1].iss_asm == 0,
2386 ("%s: inm %p is INCLUDE but ASM count is %d",
2387 __func__, inm, inm->in6m_st[1].iss_asm));
2388 }
2389 }
2390
2391 /*
2392 * Generate the filter list changes using a separate function.
2393 */
2394 if (is_filter_list_change)
2395 return (mld_v2_enqueue_filter_change(mq, inm));
2396
2397 if (type == MLD_DO_NOTHING) {
2398 CTR3(KTR_MLD, "%s: nothing to do for %s/%s",
2399 __func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2400 if_name(inm->in6m_ifp));
2401 return (0);
2402 }
2403
2404 /*
2405 * If any sources are present, we must be able to fit at least
2406 * one in the trailing space of the tail packet's mbuf,
2407 * ideally more.
2408 */
2409 minrec0len = sizeof(struct mldv2_record);
2410 if (record_has_sources)
2411 minrec0len += sizeof(struct in6_addr);
2412
2413 CTR4(KTR_MLD, "%s: queueing %s for %s/%s", __func__,
2414 mld_rec_type_to_str(type),
2415 ip6_sprintf(ip6tbuf, &inm->in6m_addr),
2416 if_name(inm->in6m_ifp));
2417
2418 /*
2419 * Check if we have a packet in the tail of the queue for this
2420 * group into which the first group record for this group will fit.
2421 * Otherwise allocate a new packet.
2422 * Always allocate leading space for IP6+RA+ICMPV6+REPORT.
2423 * Note: Group records for G/GSR query responses MUST be sent
2424 * in their own packet.
2425 */
2426 m0 = mbufq_last(mq);
2427 if (!is_group_query &&
2428 m0 != NULL &&
2429 (m0->m_pkthdr.vt_nrecs + 1 <= MLD_V2_REPORT_MAXRECS) &&
2430 (m0->m_pkthdr.len + minrec0len) <
2431 (ifp->if_mtu - MLD_MTUSPACE)) {
2432 m0srcs = (ifp->if_mtu - m0->m_pkthdr.len -
2433 sizeof(struct mldv2_record)) /
2434 sizeof(struct in6_addr);
2435 m = m0;
2436 CTR1(KTR_MLD, "%s: use existing packet", __func__);
2437 } else {
2438 if (mbufq_full(mq)) {
2439 CTR1(KTR_MLD, "%s: outbound queue full", __func__);
2440 return (-ENOMEM);
2441 }
2442 m = NULL;
2443 m0srcs = (ifp->if_mtu - MLD_MTUSPACE -
2444 sizeof(struct mldv2_record)) / sizeof(struct in6_addr);
2445 if (!is_state_change && !is_group_query)
2446 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
2447 if (m == NULL)
2448 m = m_gethdr(M_NOWAIT, MT_DATA);
2449 if (m == NULL)
2450 return (-ENOMEM);
2451
2452 mld_save_context(m, ifp);
2453
2454 CTR1(KTR_MLD, "%s: allocated first packet", __func__);
2455 }
2456
2457 /*
2458 * Append group record.
2459 * If we have sources, we don't know how many yet.
2460 */
2461 mr.mr_type = type;
2462 mr.mr_datalen = 0;
2463 mr.mr_numsrc = 0;
2464 mr.mr_addr = inm->in6m_addr;
2465 in6_clearscope(&mr.mr_addr);
2466 if (!m_append(m, sizeof(struct mldv2_record), (void *)&mr)) {
2467 if (m != m0)
2468 m_freem(m);
2469 CTR1(KTR_MLD, "%s: m_append() failed.", __func__);
2470 return (-ENOMEM);
2471 }
2472 nbytes += sizeof(struct mldv2_record);
2473
2474 /*
2475 * Append as many sources as will fit in the first packet.
2476 * If we are appending to a new packet, the chain allocation
2477 * may potentially use clusters; use m_getptr() in this case.
2478 * If we are appending to an existing packet, we need to obtain
2479 * a pointer to the group record after m_append(), in case a new
2480 * mbuf was allocated.
2481 *
2482 * Only append sources which are in-mode at t1. If we are
2483 * transitioning to MCAST_UNDEFINED state on the group, and
2484 * use_block_allow is zero, do not include source entries.
2485 * Otherwise, we need to include this source in the report.
2486 *
2487 * Only report recorded sources in our filter set when responding
2488 * to a group-source query.
2489 */
2490 if (record_has_sources) {
2491 if (m == m0) {
2492 md = m_last(m);
2493 pmr = (struct mldv2_record *)(mtod(md, uint8_t *) +
2494 md->m_len - nbytes);
2495 } else {
2496 md = m_getptr(m, 0, &off);
2497 pmr = (struct mldv2_record *)(mtod(md, uint8_t *) +
2498 off);
2499 }
2500 msrcs = 0;
2501 RB_FOREACH_SAFE(ims, ip6_msource_tree, &inm->in6m_srcs,
2502 nims) {
2503 CTR2(KTR_MLD, "%s: visit node %s", __func__,
2504 ip6_sprintf(ip6tbuf, &ims->im6s_addr));
2505 now = im6s_get_mode(inm, ims, 1);
2506 CTR2(KTR_MLD, "%s: node is %d", __func__, now);
2507 if ((now != mode) ||
2508 (now == mode &&
2509 (!use_block_allow && mode == MCAST_UNDEFINED))) {
2510 CTR1(KTR_MLD, "%s: skip node", __func__);
2511 continue;
2512 }
2513 if (is_source_query && ims->im6s_stp == 0) {
2514 CTR1(KTR_MLD, "%s: skip unrecorded node",
2515 __func__);
2516 continue;
2517 }
2518 CTR1(KTR_MLD, "%s: append node", __func__);
2519 if (!m_append(m, sizeof(struct in6_addr),
2520 (void *)&ims->im6s_addr)) {
2521 if (m != m0)
2522 m_freem(m);
2523 CTR1(KTR_MLD, "%s: m_append() failed.",
2524 __func__);
2525 return (-ENOMEM);
2526 }
2527 nbytes += sizeof(struct in6_addr);
2528 ++msrcs;
2529 if (msrcs == m0srcs)
2530 break;
2531 }
2532 CTR2(KTR_MLD, "%s: msrcs is %d this packet", __func__,
2533 msrcs);
2534 pmr->mr_numsrc = htons(msrcs);
2535 nbytes += (msrcs * sizeof(struct in6_addr));
2536 }
2537
2538 if (is_source_query && msrcs == 0) {
2539 CTR1(KTR_MLD, "%s: no recorded sources to report", __func__);
2540 if (m != m0)
2541 m_freem(m);
2542 return (0);
2543 }
2544
2545 /*
2546 * We are good to go with first packet.
2547 */
2548 if (m != m0) {
2549 CTR1(KTR_MLD, "%s: enqueueing first packet", __func__);
2550 m->m_pkthdr.vt_nrecs = 1;
2551 mbufq_enqueue(mq, m);
2552 } else
2553 m->m_pkthdr.vt_nrecs++;
2554
2555 /*
2556 * No further work needed if no source list in packet(s).
2557 */
2558 if (!record_has_sources)
2559 return (nbytes);
2560
2561 /*
2562 * Whilst sources remain to be announced, we need to allocate
2563 * a new packet and fill out as many sources as will fit.
2564 * Always try for a cluster first.
2565 */
2566 while (nims != NULL) {
2567 if (mbufq_full(mq)) {
2568 CTR1(KTR_MLD, "%s: outbound queue full", __func__);
2569 return (-ENOMEM);
2570 }
2571 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
2572 if (m == NULL)
2573 m = m_gethdr(M_NOWAIT, MT_DATA);
2574 if (m == NULL)
2575 return (-ENOMEM);
2576 mld_save_context(m, ifp);
2577 md = m_getptr(m, 0, &off);
2578 pmr = (struct mldv2_record *)(mtod(md, uint8_t *) + off);
2579 CTR1(KTR_MLD, "%s: allocated next packet", __func__);
2580
2581 if (!m_append(m, sizeof(struct mldv2_record), (void *)&mr)) {
2582 if (m != m0)
2583 m_freem(m);
2584 CTR1(KTR_MLD, "%s: m_append() failed.", __func__);
2585 return (-ENOMEM);
2586 }
2587 m->m_pkthdr.vt_nrecs = 1;
2588 nbytes += sizeof(struct mldv2_record);
2589
2590 m0srcs = (ifp->if_mtu - MLD_MTUSPACE -
2591 sizeof(struct mldv2_record)) / sizeof(struct in6_addr);
2592
2593 msrcs = 0;
2594 RB_FOREACH_FROM(ims, ip6_msource_tree, nims) {
2595 CTR2(KTR_MLD, "%s: visit node %s",
2596 __func__, ip6_sprintf(ip6tbuf, &ims->im6s_addr));
2597 now = im6s_get_mode(inm, ims, 1);
2598 if ((now != mode) ||
2599 (now == mode &&
2600 (!use_block_allow && mode == MCAST_UNDEFINED))) {
2601 CTR1(KTR_MLD, "%s: skip node", __func__);
2602 continue;
2603 }
2604 if (is_source_query && ims->im6s_stp == 0) {
2605 CTR1(KTR_MLD, "%s: skip unrecorded node",
2606 __func__);
2607 continue;
2608 }
2609 CTR1(KTR_MLD, "%s: append node", __func__);
2610 if (!m_append(m, sizeof(struct in6_addr),
2611 (void *)&ims->im6s_addr)) {
2612 if (m != m0)
2613 m_freem(m);
2614 CTR1(KTR_MLD, "%s: m_append() failed.",
2615 __func__);
2616 return (-ENOMEM);
2617 }
2618 ++msrcs;
2619 if (msrcs == m0srcs)
2620 break;
2621 }
2622 pmr->mr_numsrc = htons(msrcs);
2623 nbytes += (msrcs * sizeof(struct in6_addr));
2624
2625 CTR1(KTR_MLD, "%s: enqueueing next packet", __func__);
2626 mbufq_enqueue(mq, m);
2627 }
2628
2629 return (nbytes);
2630 }
2631
2632 /*
2633 * Type used to mark record pass completion.
2634 * We exploit the fact we can cast to this easily from the
2635 * current filter modes on each ip_msource node.
2636 */
2637 typedef enum {
2638 REC_NONE = 0x00, /* MCAST_UNDEFINED */
2639 REC_ALLOW = 0x01, /* MCAST_INCLUDE */
2640 REC_BLOCK = 0x02, /* MCAST_EXCLUDE */
2641 REC_FULL = REC_ALLOW | REC_BLOCK
2642 } rectype_t;
2643
2644 /*
2645 * Enqueue an MLDv2 filter list change to the given output queue.
2646 *
2647 * Source list filter state is held in an RB-tree. When the filter list
2648 * for a group is changed without changing its mode, we need to compute
2649 * the deltas between T0 and T1 for each source in the filter set,
2650 * and enqueue the appropriate ALLOW_NEW/BLOCK_OLD records.
2651 *
2652 * As we may potentially queue two record types, and the entire R-B tree
2653 * needs to be walked at once, we break this out into its own function
2654 * so we can generate a tightly packed queue of packets.
2655 *
2656 * XXX This could be written to only use one tree walk, although that makes
2657 * serializing into the mbuf chains a bit harder. For now we do two walks
2658 * which makes things easier on us, and it may or may not be harder on
2659 * the L2 cache.
2660 *
2661 * If successful the size of all data appended to the queue is returned,
2662 * otherwise an error code less than zero is returned, or zero if
2663 * no record(s) were appended.
2664 */
2665 static int
mld_v2_enqueue_filter_change(struct mbufq * mq,struct in6_multi * inm)2666 mld_v2_enqueue_filter_change(struct mbufq *mq, struct in6_multi *inm)
2667 {
2668 static const int MINRECLEN =
2669 sizeof(struct mldv2_record) + sizeof(struct in6_addr);
2670 struct ifnet *ifp;
2671 struct mldv2_record mr;
2672 struct mldv2_record *pmr;
2673 struct ip6_msource *ims, *nims;
2674 struct mbuf *m, *m0, *md;
2675 int m0srcs, nbytes, npbytes, off, rsrcs, schanged;
2676 uint8_t mode, now, then;
2677 rectype_t crt, drt, nrt;
2678 #ifdef KTR
2679 int nallow, nblock;
2680 char ip6tbuf[INET6_ADDRSTRLEN];
2681 #endif
2682
2683 IN6_MULTI_LIST_LOCK_ASSERT();
2684
2685 if (inm->in6m_nsrc == 0 ||
2686 (inm->in6m_st[0].iss_asm > 0 && inm->in6m_st[1].iss_asm > 0))
2687 return (0);
2688
2689 ifp = inm->in6m_ifp; /* interface */
2690 mode = inm->in6m_st[1].iss_fmode; /* filter mode at t1 */
2691 crt = REC_NONE; /* current group record type */
2692 drt = REC_NONE; /* mask of completed group record types */
2693 nrt = REC_NONE; /* record type for current node */
2694 m0srcs = 0; /* # source which will fit in current mbuf chain */
2695 npbytes = 0; /* # of bytes appended this packet */
2696 nbytes = 0; /* # of bytes appended to group's state-change queue */
2697 rsrcs = 0; /* # sources encoded in current record */
2698 schanged = 0; /* # nodes encoded in overall filter change */
2699 #ifdef KTR
2700 nallow = 0; /* # of source entries in ALLOW_NEW */
2701 nblock = 0; /* # of source entries in BLOCK_OLD */
2702 #endif
2703 nims = NULL; /* next tree node pointer */
2704
2705 /*
2706 * For each possible filter record mode.
2707 * The first kind of source we encounter tells us which
2708 * is the first kind of record we start appending.
2709 * If a node transitioned to UNDEFINED at t1, its mode is treated
2710 * as the inverse of the group's filter mode.
2711 */
2712 while (drt != REC_FULL) {
2713 do {
2714 m0 = mbufq_last(mq);
2715 if (m0 != NULL &&
2716 (m0->m_pkthdr.vt_nrecs + 1 <=
2717 MLD_V2_REPORT_MAXRECS) &&
2718 (m0->m_pkthdr.len + MINRECLEN) <
2719 (ifp->if_mtu - MLD_MTUSPACE)) {
2720 m = m0;
2721 m0srcs = (ifp->if_mtu - m0->m_pkthdr.len -
2722 sizeof(struct mldv2_record)) /
2723 sizeof(struct in6_addr);
2724 CTR1(KTR_MLD,
2725 "%s: use previous packet", __func__);
2726 } else {
2727 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
2728 if (m == NULL)
2729 m = m_gethdr(M_NOWAIT, MT_DATA);
2730 if (m == NULL) {
2731 CTR1(KTR_MLD,
2732 "%s: m_get*() failed", __func__);
2733 return (-ENOMEM);
2734 }
2735 m->m_pkthdr.vt_nrecs = 0;
2736 mld_save_context(m, ifp);
2737 m0srcs = (ifp->if_mtu - MLD_MTUSPACE -
2738 sizeof(struct mldv2_record)) /
2739 sizeof(struct in6_addr);
2740 npbytes = 0;
2741 CTR1(KTR_MLD,
2742 "%s: allocated new packet", __func__);
2743 }
2744 /*
2745 * Append the MLD group record header to the
2746 * current packet's data area.
2747 * Recalculate pointer to free space for next
2748 * group record, in case m_append() allocated
2749 * a new mbuf or cluster.
2750 */
2751 memset(&mr, 0, sizeof(mr));
2752 mr.mr_addr = inm->in6m_addr;
2753 in6_clearscope(&mr.mr_addr);
2754 if (!m_append(m, sizeof(mr), (void *)&mr)) {
2755 if (m != m0)
2756 m_freem(m);
2757 CTR1(KTR_MLD,
2758 "%s: m_append() failed", __func__);
2759 return (-ENOMEM);
2760 }
2761 npbytes += sizeof(struct mldv2_record);
2762 if (m != m0) {
2763 /* new packet; offset in chain */
2764 md = m_getptr(m, npbytes -
2765 sizeof(struct mldv2_record), &off);
2766 pmr = (struct mldv2_record *)(mtod(md,
2767 uint8_t *) + off);
2768 } else {
2769 /* current packet; offset from last append */
2770 md = m_last(m);
2771 pmr = (struct mldv2_record *)(mtod(md,
2772 uint8_t *) + md->m_len -
2773 sizeof(struct mldv2_record));
2774 }
2775 /*
2776 * Begin walking the tree for this record type
2777 * pass, or continue from where we left off
2778 * previously if we had to allocate a new packet.
2779 * Only report deltas in-mode at t1.
2780 * We need not report included sources as allowed
2781 * if we are in inclusive mode on the group,
2782 * however the converse is not true.
2783 */
2784 rsrcs = 0;
2785 if (nims == NULL) {
2786 nims = RB_MIN(ip6_msource_tree,
2787 &inm->in6m_srcs);
2788 }
2789 RB_FOREACH_FROM(ims, ip6_msource_tree, nims) {
2790 CTR2(KTR_MLD, "%s: visit node %s", __func__,
2791 ip6_sprintf(ip6tbuf, &ims->im6s_addr));
2792 now = im6s_get_mode(inm, ims, 1);
2793 then = im6s_get_mode(inm, ims, 0);
2794 CTR3(KTR_MLD, "%s: mode: t0 %d, t1 %d",
2795 __func__, then, now);
2796 if (now == then) {
2797 CTR1(KTR_MLD,
2798 "%s: skip unchanged", __func__);
2799 continue;
2800 }
2801 if (mode == MCAST_EXCLUDE &&
2802 now == MCAST_INCLUDE) {
2803 CTR1(KTR_MLD,
2804 "%s: skip IN src on EX group",
2805 __func__);
2806 continue;
2807 }
2808 nrt = (rectype_t)now;
2809 if (nrt == REC_NONE)
2810 nrt = (rectype_t)(~mode & REC_FULL);
2811 if (schanged++ == 0) {
2812 crt = nrt;
2813 } else if (crt != nrt)
2814 continue;
2815 if (!m_append(m, sizeof(struct in6_addr),
2816 (void *)&ims->im6s_addr)) {
2817 if (m != m0)
2818 m_freem(m);
2819 CTR1(KTR_MLD,
2820 "%s: m_append() failed", __func__);
2821 return (-ENOMEM);
2822 }
2823 #ifdef KTR
2824 nallow += !!(crt == REC_ALLOW);
2825 nblock += !!(crt == REC_BLOCK);
2826 #endif
2827 if (++rsrcs == m0srcs)
2828 break;
2829 }
2830 /*
2831 * If we did not append any tree nodes on this
2832 * pass, back out of allocations.
2833 */
2834 if (rsrcs == 0) {
2835 npbytes -= sizeof(struct mldv2_record);
2836 if (m != m0) {
2837 CTR1(KTR_MLD,
2838 "%s: m_free(m)", __func__);
2839 m_freem(m);
2840 } else {
2841 CTR1(KTR_MLD,
2842 "%s: m_adj(m, -mr)", __func__);
2843 m_adj(m, -((int)sizeof(
2844 struct mldv2_record)));
2845 }
2846 continue;
2847 }
2848 npbytes += (rsrcs * sizeof(struct in6_addr));
2849 if (crt == REC_ALLOW)
2850 pmr->mr_type = MLD_ALLOW_NEW_SOURCES;
2851 else if (crt == REC_BLOCK)
2852 pmr->mr_type = MLD_BLOCK_OLD_SOURCES;
2853 pmr->mr_numsrc = htons(rsrcs);
2854 /*
2855 * Count the new group record, and enqueue this
2856 * packet if it wasn't already queued.
2857 */
2858 m->m_pkthdr.vt_nrecs++;
2859 if (m != m0)
2860 mbufq_enqueue(mq, m);
2861 nbytes += npbytes;
2862 } while (nims != NULL);
2863 drt |= crt;
2864 crt = (~crt & REC_FULL);
2865 }
2866
2867 CTR3(KTR_MLD, "%s: queued %d ALLOW_NEW, %d BLOCK_OLD", __func__,
2868 nallow, nblock);
2869
2870 return (nbytes);
2871 }
2872
2873 static int
mld_v2_merge_state_changes(struct in6_multi * inm,struct mbufq * scq)2874 mld_v2_merge_state_changes(struct in6_multi *inm, struct mbufq *scq)
2875 {
2876 struct mbufq *gq;
2877 struct mbuf *m; /* pending state-change */
2878 struct mbuf *m0; /* copy of pending state-change */
2879 struct mbuf *mt; /* last state-change in packet */
2880 int docopy, domerge;
2881 u_int recslen;
2882
2883 docopy = 0;
2884 domerge = 0;
2885 recslen = 0;
2886
2887 IN6_MULTI_LIST_LOCK_ASSERT();
2888 MLD_LOCK_ASSERT();
2889
2890 /*
2891 * If there are further pending retransmissions, make a writable
2892 * copy of each queued state-change message before merging.
2893 */
2894 if (inm->in6m_scrv > 0)
2895 docopy = 1;
2896
2897 gq = &inm->in6m_scq;
2898 #ifdef KTR
2899 if (mbufq_first(gq) == NULL) {
2900 CTR2(KTR_MLD, "%s: WARNING: queue for inm %p is empty",
2901 __func__, inm);
2902 }
2903 #endif
2904
2905 m = mbufq_first(gq);
2906 while (m != NULL) {
2907 /*
2908 * Only merge the report into the current packet if
2909 * there is sufficient space to do so; an MLDv2 report
2910 * packet may only contain 65,535 group records.
2911 * Always use a simple mbuf chain concatentation to do this,
2912 * as large state changes for single groups may have
2913 * allocated clusters.
2914 */
2915 domerge = 0;
2916 mt = mbufq_last(scq);
2917 if (mt != NULL) {
2918 recslen = m_length(m, NULL);
2919
2920 if ((mt->m_pkthdr.vt_nrecs +
2921 m->m_pkthdr.vt_nrecs <=
2922 MLD_V2_REPORT_MAXRECS) &&
2923 (mt->m_pkthdr.len + recslen <=
2924 (inm->in6m_ifp->if_mtu - MLD_MTUSPACE)))
2925 domerge = 1;
2926 }
2927
2928 if (!domerge && mbufq_full(gq)) {
2929 CTR2(KTR_MLD,
2930 "%s: outbound queue full, skipping whole packet %p",
2931 __func__, m);
2932 mt = m->m_nextpkt;
2933 if (!docopy)
2934 m_freem(m);
2935 m = mt;
2936 continue;
2937 }
2938
2939 if (!docopy) {
2940 CTR2(KTR_MLD, "%s: dequeueing %p", __func__, m);
2941 m0 = mbufq_dequeue(gq);
2942 m = m0->m_nextpkt;
2943 } else {
2944 CTR2(KTR_MLD, "%s: copying %p", __func__, m);
2945 m0 = m_dup(m, M_NOWAIT);
2946 if (m0 == NULL)
2947 return (ENOMEM);
2948 m0->m_nextpkt = NULL;
2949 m = m->m_nextpkt;
2950 }
2951
2952 if (!domerge) {
2953 CTR3(KTR_MLD, "%s: queueing %p to scq %p)",
2954 __func__, m0, scq);
2955 mbufq_enqueue(scq, m0);
2956 } else {
2957 struct mbuf *mtl; /* last mbuf of packet mt */
2958
2959 CTR3(KTR_MLD, "%s: merging %p with ifscq tail %p)",
2960 __func__, m0, mt);
2961
2962 mtl = m_last(mt);
2963 m0->m_flags &= ~M_PKTHDR;
2964 mt->m_pkthdr.len += recslen;
2965 mt->m_pkthdr.vt_nrecs +=
2966 m0->m_pkthdr.vt_nrecs;
2967
2968 mtl->m_next = m0;
2969 }
2970 }
2971
2972 return (0);
2973 }
2974
2975 /*
2976 * Respond to a pending MLDv2 General Query.
2977 */
2978 static void
mld_v2_dispatch_general_query(struct mld_ifsoftc * mli)2979 mld_v2_dispatch_general_query(struct mld_ifsoftc *mli)
2980 {
2981 struct ifmultiaddr *ifma;
2982 struct ifnet *ifp;
2983 struct in6_multi *inm;
2984 int retval __unused;
2985
2986 NET_EPOCH_ASSERT();
2987 IN6_MULTI_LIST_LOCK_ASSERT();
2988 MLD_LOCK_ASSERT();
2989
2990 KASSERT(mli->mli_version == MLD_VERSION_2,
2991 ("%s: called when version %d", __func__, mli->mli_version));
2992
2993 /*
2994 * Check that there are some packets queued. If so, send them first.
2995 * For large number of groups the reply to general query can take
2996 * many packets, we should finish sending them before starting of
2997 * queuing the new reply.
2998 */
2999 if (!mbufq_empty(&mli->mli_gq))
3000 goto send;
3001
3002 ifp = mli->mli_ifp;
3003
3004 CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
3005 inm = in6m_ifmultiaddr_get_inm(ifma);
3006 if (inm == NULL)
3007 continue;
3008 KASSERT(ifp == inm->in6m_ifp,
3009 ("%s: inconsistent ifp", __func__));
3010
3011 switch (inm->in6m_state) {
3012 case MLD_NOT_MEMBER:
3013 case MLD_SILENT_MEMBER:
3014 break;
3015 case MLD_REPORTING_MEMBER:
3016 case MLD_IDLE_MEMBER:
3017 case MLD_LAZY_MEMBER:
3018 case MLD_SLEEPING_MEMBER:
3019 case MLD_AWAKENING_MEMBER:
3020 inm->in6m_state = MLD_REPORTING_MEMBER;
3021 retval = mld_v2_enqueue_group_record(&mli->mli_gq,
3022 inm, 0, 0, 0, 0);
3023 CTR2(KTR_MLD, "%s: enqueue record = %d",
3024 __func__, retval);
3025 break;
3026 case MLD_G_QUERY_PENDING_MEMBER:
3027 case MLD_SG_QUERY_PENDING_MEMBER:
3028 case MLD_LEAVING_MEMBER:
3029 break;
3030 }
3031 }
3032
3033 send:
3034 mld_dispatch_queue(&mli->mli_gq, MLD_MAX_RESPONSE_BURST);
3035
3036 /*
3037 * Slew transmission of bursts over 500ms intervals.
3038 */
3039 if (mbufq_first(&mli->mli_gq) != NULL) {
3040 mli->mli_v2_timer = 1 + MLD_RANDOM_DELAY(
3041 MLD_RESPONSE_BURST_INTERVAL);
3042 V_interface_timers_running6 = 1;
3043 }
3044 }
3045
3046 /*
3047 * Transmit the next pending message in the output queue.
3048 *
3049 * VIMAGE: Needs to store/restore vnet pointer on a per-mbuf-chain basis.
3050 * MRT: Nothing needs to be done, as MLD traffic is always local to
3051 * a link and uses a link-scope multicast address.
3052 */
3053 static void
mld_dispatch_packet(struct mbuf * m)3054 mld_dispatch_packet(struct mbuf *m)
3055 {
3056 struct ip6_moptions im6o;
3057 struct ifnet *ifp;
3058 struct ifnet *oifp;
3059 struct mbuf *m0;
3060 struct mbuf *md;
3061 struct ip6_hdr *ip6;
3062 struct mld_hdr *mld;
3063 int error;
3064 int off;
3065 int type;
3066 uint32_t ifindex;
3067
3068 CTR2(KTR_MLD, "%s: transmit %p", __func__, m);
3069 NET_EPOCH_ASSERT();
3070
3071 /*
3072 * Set VNET image pointer from enqueued mbuf chain
3073 * before doing anything else. Whilst we use interface
3074 * indexes to guard against interface detach, they are
3075 * unique to each VIMAGE and must be retrieved.
3076 */
3077 ifindex = mld_restore_context(m);
3078
3079 /*
3080 * Check if the ifnet still exists. This limits the scope of
3081 * any race in the absence of a global ifp lock for low cost
3082 * (an array lookup).
3083 */
3084 ifp = ifnet_byindex(ifindex);
3085 if (ifp == NULL) {
3086 CTR3(KTR_MLD, "%s: dropped %p as ifindex %u went away.",
3087 __func__, m, ifindex);
3088 m_freem(m);
3089 IP6STAT_INC(ip6s_noroute);
3090 goto out;
3091 }
3092
3093 im6o.im6o_multicast_hlim = 1;
3094 im6o.im6o_multicast_loop = (V_ip6_mrouter != NULL);
3095 im6o.im6o_multicast_ifp = ifp;
3096
3097 if (m->m_flags & M_MLDV1) {
3098 m0 = m;
3099 } else {
3100 m0 = mld_v2_encap_report(ifp, m);
3101 if (m0 == NULL) {
3102 CTR2(KTR_MLD, "%s: dropped %p", __func__, m);
3103 IP6STAT_INC(ip6s_odropped);
3104 goto out;
3105 }
3106 }
3107
3108 mld_scrub_context(m0);
3109 m_clrprotoflags(m);
3110 m0->m_pkthdr.rcvif = V_loif;
3111
3112 ip6 = mtod(m0, struct ip6_hdr *);
3113 #if 0
3114 (void)in6_setscope(&ip6->ip6_dst, ifp, NULL); /* XXX LOR */
3115 #else
3116 /*
3117 * XXX XXX Break some KPI rules to prevent an LOR which would
3118 * occur if we called in6_setscope() at transmission.
3119 * See comments at top of file.
3120 */
3121 MLD_EMBEDSCOPE(&ip6->ip6_dst, ifp->if_index);
3122 #endif
3123
3124 /*
3125 * Retrieve the ICMPv6 type before handoff to ip6_output(),
3126 * so we can bump the stats.
3127 */
3128 md = m_getptr(m0, sizeof(struct ip6_hdr), &off);
3129 mld = (struct mld_hdr *)(mtod(md, uint8_t *) + off);
3130 type = mld->mld_type;
3131
3132 oifp = NULL;
3133 error = ip6_output(m0, &mld_po, NULL, IPV6_UNSPECSRC, &im6o,
3134 &oifp, NULL);
3135 if (error) {
3136 CTR3(KTR_MLD, "%s: ip6_output(%p) = %d", __func__, m0, error);
3137 goto out;
3138 }
3139 ICMP6STAT_INC2(icp6s_outhist, type);
3140 if (oifp != NULL) {
3141 icmp6_ifstat_inc(oifp, ifs6_out_msg);
3142 switch (type) {
3143 case MLD_LISTENER_REPORT:
3144 case MLDV2_LISTENER_REPORT:
3145 icmp6_ifstat_inc(oifp, ifs6_out_mldreport);
3146 break;
3147 case MLD_LISTENER_DONE:
3148 icmp6_ifstat_inc(oifp, ifs6_out_mlddone);
3149 break;
3150 }
3151 }
3152 out:
3153 return;
3154 }
3155
3156 /*
3157 * Encapsulate an MLDv2 report.
3158 *
3159 * KAME IPv6 requires that hop-by-hop options be passed separately,
3160 * and that the IPv6 header be prepended in a separate mbuf.
3161 *
3162 * Returns a pointer to the new mbuf chain head, or NULL if the
3163 * allocation failed.
3164 */
3165 static struct mbuf *
mld_v2_encap_report(struct ifnet * ifp,struct mbuf * m)3166 mld_v2_encap_report(struct ifnet *ifp, struct mbuf *m)
3167 {
3168 struct mbuf *mh;
3169 struct mldv2_report *mld;
3170 struct ip6_hdr *ip6;
3171 struct in6_ifaddr *ia;
3172 int mldreclen;
3173
3174 KASSERT(ifp != NULL, ("%s: null ifp", __func__));
3175 KASSERT((m->m_flags & M_PKTHDR),
3176 ("%s: mbuf chain %p is !M_PKTHDR", __func__, m));
3177
3178 /*
3179 * RFC3590: OK to send as :: or tentative during DAD.
3180 */
3181 NET_EPOCH_ASSERT();
3182 ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
3183 if (ia == NULL)
3184 CTR1(KTR_MLD, "%s: warning: ia is NULL", __func__);
3185
3186 mh = m_gethdr(M_NOWAIT, MT_DATA);
3187 if (mh == NULL) {
3188 if (ia != NULL)
3189 ifa_free(&ia->ia_ifa);
3190 m_freem(m);
3191 return (NULL);
3192 }
3193 M_ALIGN(mh, sizeof(struct ip6_hdr) + sizeof(struct mldv2_report));
3194
3195 mldreclen = m_length(m, NULL);
3196 CTR2(KTR_MLD, "%s: mldreclen is %d", __func__, mldreclen);
3197
3198 mh->m_len = sizeof(struct ip6_hdr) + sizeof(struct mldv2_report);
3199 mh->m_pkthdr.len = sizeof(struct ip6_hdr) +
3200 sizeof(struct mldv2_report) + mldreclen;
3201
3202 ip6 = mtod(mh, struct ip6_hdr *);
3203 ip6->ip6_flow = 0;
3204 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
3205 ip6->ip6_vfc |= IPV6_VERSION;
3206 ip6->ip6_nxt = IPPROTO_ICMPV6;
3207 ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any;
3208 if (ia != NULL)
3209 ifa_free(&ia->ia_ifa);
3210 ip6->ip6_dst = in6addr_linklocal_allv2routers;
3211 /* scope ID will be set in netisr */
3212
3213 mld = (struct mldv2_report *)(ip6 + 1);
3214 mld->mld_type = MLDV2_LISTENER_REPORT;
3215 mld->mld_code = 0;
3216 mld->mld_cksum = 0;
3217 mld->mld_v2_reserved = 0;
3218 mld->mld_v2_numrecs = htons(m->m_pkthdr.vt_nrecs);
3219 m->m_pkthdr.vt_nrecs = 0;
3220
3221 mh->m_next = m;
3222 mld->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6,
3223 sizeof(struct ip6_hdr), sizeof(struct mldv2_report) + mldreclen);
3224 return (mh);
3225 }
3226
3227 #ifdef KTR
3228 static char *
mld_rec_type_to_str(const int type)3229 mld_rec_type_to_str(const int type)
3230 {
3231
3232 switch (type) {
3233 case MLD_CHANGE_TO_EXCLUDE_MODE:
3234 return "TO_EX";
3235 break;
3236 case MLD_CHANGE_TO_INCLUDE_MODE:
3237 return "TO_IN";
3238 break;
3239 case MLD_MODE_IS_EXCLUDE:
3240 return "MODE_EX";
3241 break;
3242 case MLD_MODE_IS_INCLUDE:
3243 return "MODE_IN";
3244 break;
3245 case MLD_ALLOW_NEW_SOURCES:
3246 return "ALLOW_NEW";
3247 break;
3248 case MLD_BLOCK_OLD_SOURCES:
3249 return "BLOCK_OLD";
3250 break;
3251 default:
3252 break;
3253 }
3254 return "unknown";
3255 }
3256 #endif
3257
3258 static void
mld_init(void * unused __unused)3259 mld_init(void *unused __unused)
3260 {
3261
3262 CTR1(KTR_MLD, "%s: initializing", __func__);
3263 MLD_LOCK_INIT();
3264
3265 ip6_initpktopts(&mld_po);
3266 mld_po.ip6po_hlim = 1;
3267 mld_po.ip6po_hbh = &mld_ra.hbh;
3268 mld_po.ip6po_prefer_tempaddr = IP6PO_TEMPADDR_NOTPREFER;
3269 mld_po.ip6po_flags = IP6PO_DONTFRAG;
3270
3271 callout_init(&mldslow_callout, 1);
3272 callout_reset(&mldslow_callout, hz / MLD_SLOWHZ, mld_slowtimo, NULL);
3273 callout_init(&mldfast_callout, 1);
3274 callout_reset(&mldfast_callout, hz / MLD_FASTHZ, mld_fasttimo, NULL);
3275 }
3276 SYSINIT(mld_init, SI_SUB_PROTO_MC, SI_ORDER_MIDDLE, mld_init, NULL);
3277
3278 static void
mld_uninit(void * unused __unused)3279 mld_uninit(void *unused __unused)
3280 {
3281
3282 CTR1(KTR_MLD, "%s: tearing down", __func__);
3283 callout_drain(&mldslow_callout);
3284 callout_drain(&mldfast_callout);
3285 MLD_LOCK_DESTROY();
3286 }
3287 SYSUNINIT(mld_uninit, SI_SUB_PROTO_MC, SI_ORDER_MIDDLE, mld_uninit, NULL);
3288
3289 static void
vnet_mld_init(const void * unused __unused)3290 vnet_mld_init(const void *unused __unused)
3291 {
3292
3293 CTR1(KTR_MLD, "%s: initializing", __func__);
3294
3295 LIST_INIT(&V_mli_head);
3296 }
3297 VNET_SYSINIT(vnet_mld_init, SI_SUB_PROTO_MC, SI_ORDER_ANY, vnet_mld_init,
3298 NULL);
3299
3300 static void
vnet_mld_uninit(const void * unused __unused)3301 vnet_mld_uninit(const void *unused __unused)
3302 {
3303
3304 /* This can happen if we shutdown the network stack. */
3305 CTR1(KTR_MLD, "%s: tearing down", __func__);
3306 }
3307 VNET_SYSUNINIT(vnet_mld_uninit, SI_SUB_PROTO_MC, SI_ORDER_ANY, vnet_mld_uninit,
3308 NULL);
3309
3310 static int
mld_modevent(module_t mod,int type,void * unused __unused)3311 mld_modevent(module_t mod, int type, void *unused __unused)
3312 {
3313
3314 switch (type) {
3315 case MOD_LOAD:
3316 case MOD_UNLOAD:
3317 break;
3318 default:
3319 return (EOPNOTSUPP);
3320 }
3321 return (0);
3322 }
3323
3324 static moduledata_t mld_mod = {
3325 "mld",
3326 mld_modevent,
3327 0
3328 };
3329 DECLARE_MODULE(mld, mld_mod, SI_SUB_PROTO_MC, SI_ORDER_ANY);
3330