2 * Copyright (C) 1998 WIDE Project.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the project nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * $KAME: mld6.c,v 1.27 2001/04/04 05:17:30 itojun Exp $
33 * Copyright (c) 1988 Stephen Deering.
34 * Copyright (c) 1992, 1993
35 * The Regents of the University of California. All rights reserved.
37 * This code is derived from software contributed to Berkeley by
38 * Stephen Deering of Stanford University.
40 * Redistribution and use in source and binary forms, with or without
41 * modification, are permitted provided that the following conditions
43 * 1. Redistributions of source code must retain the above copyright
44 * notice, this list of conditions and the following disclaimer.
45 * 2. Redistributions in binary form must reproduce the above copyright
46 * notice, this list of conditions and the following disclaimer in the
47 * documentation and/or other materials provided with the distribution.
48 * 4. Neither the name of the University nor the names of its contributors
49 * may be used to endorse or promote products derived from this software
50 * without specific prior written permission.
52 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64 * @(#)igmp.c 8.1 (Berkeley) 7/19/93
67 #include <sys/cdefs.h>
68 __FBSDID("$FreeBSD$");
71 #include "opt_inet6.h"
73 #include <sys/param.h>
74 #include <sys/systm.h>
76 #include <sys/socket.h>
77 #include <sys/protosw.h>
78 #include <sys/syslog.h>
79 #include <sys/kernel.h>
80 #include <sys/callout.h>
81 #include <sys/malloc.h>
85 #include <netinet/in.h>
86 #include <netinet/in_var.h>
87 #include <netinet6/in6_var.h>
88 #include <netinet/ip6.h>
89 #include <netinet6/ip6_var.h>
90 #include <netinet6/scope6_var.h>
91 #include <netinet/icmp6.h>
92 #include <netinet6/mld6_var.h>
98 /* denotes that the MLD max response delay field specifies time in milliseconds */
99 #define MLD_TIMER_SCALE 1000
101 * time between repetitions of a node's initial report of interest in a
102 * multicast address(in seconds)
104 #define MLD_UNSOLICITED_REPORT_INTERVAL 10
106 static struct ip6_pktopts ip6_opts;
108 static void mld6_sendpkt(struct in6_multi *, int, const struct in6_addr *);
109 static void mld_starttimer(struct in6_multi *);
110 static void mld_stoptimer(struct in6_multi *);
111 static void mld_timeo(struct in6_multi *);
112 static u_long mld_timerresid(struct in6_multi *);
117 static u_int8_t hbh_buf[8];
118 struct ip6_hbh *hbh = (struct ip6_hbh *)hbh_buf;
119 u_int16_t rtalert_code = htons((u_int16_t)IP6OPT_RTALERT_MLD);
121 /* ip6h_nxt will be fill in later */
122 hbh->ip6h_len = 0; /* (8 >> 3) - 1 */
124 /* XXX: grotty hard coding... */
125 hbh_buf[2] = IP6OPT_PADN; /* 2 byte padding */
127 hbh_buf[4] = IP6OPT_ROUTER_ALERT;
128 hbh_buf[5] = IP6OPT_RTALERT_LEN - 2;
129 bcopy((caddr_t)&rtalert_code, &hbh_buf[6], sizeof(u_int16_t));
131 ip6_initpktopts(&ip6_opts);
132 ip6_opts.ip6po_hbh = hbh;
136 mld_starttimer(struct in6_multi *in6m)
141 in6m->in6m_timer_expire.tv_sec = now.tv_sec + in6m->in6m_timer / hz;
142 in6m->in6m_timer_expire.tv_usec = now.tv_usec +
143 (in6m->in6m_timer % hz) * (1000000 / hz);
144 if (in6m->in6m_timer_expire.tv_usec > 1000000) {
145 in6m->in6m_timer_expire.tv_sec++;
146 in6m->in6m_timer_expire.tv_usec -= 1000000;
149 /* start or restart the timer */
150 callout_reset(in6m->in6m_timer_ch, in6m->in6m_timer,
151 (void (*)(void *))mld_timeo, in6m);
155 mld_stoptimer(struct in6_multi *in6m)
157 if (in6m->in6m_timer == IN6M_TIMER_UNDEF)
160 callout_stop(in6m->in6m_timer_ch);
161 in6m->in6m_timer = IN6M_TIMER_UNDEF;
165 mld_timeo(struct in6_multi *in6m)
169 in6m->in6m_timer = IN6M_TIMER_UNDEF;
171 callout_stop(in6m->in6m_timer_ch);
173 switch (in6m->in6m_state) {
174 case MLD_REPORTPENDING:
175 mld6_start_listening(in6m);
178 mld6_sendpkt(in6m, MLD_LISTENER_REPORT, NULL);
186 mld_timerresid(struct in6_multi *in6m)
188 struct timeval now, diff;
192 if (now.tv_sec > in6m->in6m_timer_expire.tv_sec ||
193 (now.tv_sec == in6m->in6m_timer_expire.tv_sec &&
194 now.tv_usec > in6m->in6m_timer_expire.tv_usec)) {
197 diff = in6m->in6m_timer_expire;
198 diff.tv_sec -= now.tv_sec;
199 diff.tv_usec -= now.tv_usec;
200 if (diff.tv_usec < 0) {
202 diff.tv_usec += 1000000;
205 /* return the remaining time in milliseconds */
206 return (diff.tv_sec * 1000 + diff.tv_usec / 1000);
210 mld6_start_listening(struct in6_multi *in6m)
212 struct in6_addr all_in6;
217 * The node never sends a Report or Done for the link-scope all-nodes
219 * MLD messages are never sent for multicast addresses whose scope is 0
220 * (reserved) or 1 (node-local).
222 all_in6 = in6addr_linklocal_allnodes;
223 if (in6_setscope(&all_in6, in6m->in6m_ifp, NULL)) {
224 /* XXX: this should not happen! */
225 in6m->in6m_timer = 0;
226 in6m->in6m_state = MLD_OTHERLISTENER;
228 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &all_in6) ||
229 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) <
230 IPV6_ADDR_SCOPE_LINKLOCAL) {
231 in6m->in6m_timer = 0;
232 in6m->in6m_state = MLD_OTHERLISTENER;
234 mld6_sendpkt(in6m, MLD_LISTENER_REPORT, NULL);
235 in6m->in6m_timer = arc4random() %
236 MLD_UNSOLICITED_REPORT_INTERVAL * hz;
237 in6m->in6m_state = MLD_IREPORTEDLAST;
239 mld_starttimer(in6m);
245 mld6_stop_listening(struct in6_multi *in6m)
247 struct in6_addr allnode, allrouter;
249 allnode = in6addr_linklocal_allnodes;
250 if (in6_setscope(&allnode, in6m->in6m_ifp, NULL)) {
251 /* XXX: this should not happen! */
254 allrouter = in6addr_linklocal_allrouters;
255 if (in6_setscope(&allrouter, in6m->in6m_ifp, NULL)) {
259 if (in6m->in6m_state == MLD_IREPORTEDLAST &&
260 !IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &allnode) &&
261 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) >
262 IPV6_ADDR_SCOPE_INTFACELOCAL) {
263 mld6_sendpkt(in6m, MLD_LISTENER_DONE, &allrouter);
268 mld6_input(struct mbuf *m, int off)
270 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
271 struct mld_hdr *mldh;
272 struct ifnet *ifp = m->m_pkthdr.rcvif;
273 struct in6_multi *in6m;
274 struct in6_addr mld_addr, all_in6;
275 struct in6_ifaddr *ia;
276 struct ifmultiaddr *ifma;
277 u_long timer; /* timer value in the MLD query header */
279 #ifndef PULLDOWN_TEST
280 IP6_EXTHDR_CHECK(m, off, sizeof(*mldh),);
281 mldh = (struct mld_hdr *)(mtod(m, caddr_t) + off);
283 IP6_EXTHDR_GET(mldh, struct mld_hdr *, m, off, sizeof(*mldh));
285 icmp6stat.icp6s_tooshort++;
290 /* source address validation */
291 ip6 = mtod(m, struct ip6_hdr *); /* in case mpullup */
292 if (!IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) {
293 char ip6bufs[INET6_ADDRSTRLEN], ip6bufg[INET6_ADDRSTRLEN];
295 "mld6_input: src %s is not link-local (grp=%s)\n",
296 ip6_sprintf(ip6bufs, &ip6->ip6_src),
297 ip6_sprintf(ip6bufg, &mldh->mld_addr));
299 * spec (RFC2710) does not explicitly
300 * specify to discard the packet from a non link-local
301 * source address. But we believe it's expected to do so.
302 * XXX: do we have to allow :: as source?
309 * make a copy for local work (in6_setscope() may modify the 1st arg)
311 mld_addr = mldh->mld_addr;
312 if (in6_setscope(&mld_addr, ifp, NULL)) {
313 /* XXX: this should not happen! */
319 * In the MLD6 specification, there are 3 states and a flag.
321 * In Non-Listener state, we simply don't have a membership record.
322 * In Delaying Listener state, our timer is running (in6m->in6m_timer)
323 * In Idle Listener state, our timer is not running
324 * (in6m->in6m_timer==IN6M_TIMER_UNDEF)
326 * The flag is in6m->in6m_state, it is set to MLD_OTHERLISTENER if
327 * we have heard a report from another member, or MLD_IREPORTEDLAST
328 * if we sent the last report.
330 switch(mldh->mld_type) {
331 case MLD_LISTENER_QUERY:
332 if (ifp->if_flags & IFF_LOOPBACK)
335 if (!IN6_IS_ADDR_UNSPECIFIED(&mld_addr) &&
336 !IN6_IS_ADDR_MULTICAST(&mld_addr))
337 break; /* print error or log stat? */
339 all_in6 = in6addr_linklocal_allnodes;
340 if (in6_setscope(&all_in6, ifp, NULL)) {
341 /* XXX: this should not happen! */
346 * - Start the timers in all of our membership records
347 * that the query applies to for the interface on
348 * which the query arrived excl. those that belong
349 * to the "all-nodes" group (ff02::1).
350 * - Restart any timer that is already running but has
351 * A value longer than the requested timeout.
352 * - Use the value specified in the query message as
353 * the maximum timeout.
355 timer = ntohs(mldh->mld_maxdelay);
362 * XXX: System timer resolution is too low to handle Max
363 * Response Delay, so set 1 to the internal timer even if
364 * the calculated value equals to zero when Max Response
367 timer = ntohs(mldh->mld_maxdelay) * PR_FASTHZ / MLD_TIMER_SCALE;
368 if (timer == 0 && mldh->mld_maxdelay)
372 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
373 if (ifma->ifma_addr->sa_family != AF_INET6)
375 in6m = (struct in6_multi *)ifma->ifma_protospec;
377 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &all_in6) ||
378 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) <
379 IPV6_ADDR_SCOPE_LINKLOCAL)
382 if (IN6_IS_ADDR_UNSPECIFIED(&mld_addr) ||
383 IN6_ARE_ADDR_EQUAL(&mld_addr, &in6m->in6m_addr)) {
385 /* send a report immediately */
387 mld6_sendpkt(in6m, MLD_LISTENER_REPORT,
389 in6m->in6m_timer = 0; /* reset timer */
390 in6m->in6m_state = MLD_IREPORTEDLAST;
392 else if (in6m->in6m_timer == IN6M_TIMER_UNDEF ||
393 mld_timerresid(in6m) > timer) {
395 1 + (arc4random() % timer) * hz / 1000;
396 mld_starttimer(in6m);
403 case MLD_LISTENER_REPORT:
405 * For fast leave to work, we have to know that we are the
406 * last person to send a report for this group. Reports
407 * can potentially get looped back if we are a multicast
408 * router, so discard reports sourced by me.
409 * Note that it is impossible to check IFF_LOOPBACK flag of
410 * ifp for this purpose, since ip6_mloopback pass the physical
411 * interface to looutput.
413 if (m->m_flags & M_LOOP) /* XXX: grotty flag, but efficient */
416 if (!IN6_IS_ADDR_MULTICAST(&mld_addr))
420 * If we belong to the group being reported, stop
421 * our timer for that group.
423 IN6_LOOKUP_MULTI(mld_addr, ifp, in6m);
425 in6m->in6m_timer = 0; /* transit to idle state */
426 in6m->in6m_state = MLD_OTHERLISTENER; /* clear flag */
429 default: /* this is impossible */
430 log(LOG_ERR, "mld6_input: illegal type(%d)", mldh->mld_type);
438 mld6_sendpkt(struct in6_multi *in6m, int type, const struct in6_addr *dst)
440 struct mbuf *mh, *md;
441 struct mld_hdr *mldh;
443 struct ip6_moptions im6o;
444 struct in6_ifaddr *ia;
445 struct ifnet *ifp = in6m->in6m_ifp;
446 struct ifnet *outif = NULL;
449 * At first, find a link local address on the outgoing interface
450 * to use as the source address of the MLD packet.
452 if ((ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST))
457 * Allocate mbufs to store ip6 header and MLD header.
458 * We allocate 2 mbufs and make chain in advance because
459 * it is more convenient when inserting the hop-by-hop option later.
461 MGETHDR(mh, M_DONTWAIT, MT_HEADER);
464 MGET(md, M_DONTWAIT, MT_DATA);
471 mh->m_pkthdr.rcvif = NULL;
472 mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld_hdr);
473 mh->m_len = sizeof(struct ip6_hdr);
474 MH_ALIGN(mh, sizeof(struct ip6_hdr));
476 /* fill in the ip6 header */
477 ip6 = mtod(mh, struct ip6_hdr *);
479 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
480 ip6->ip6_vfc |= IPV6_VERSION;
481 /* ip6_plen will be set later */
482 ip6->ip6_nxt = IPPROTO_ICMPV6;
483 /* ip6_hlim will be set by im6o.im6o_multicast_hlim */
484 ip6->ip6_src = ia->ia_addr.sin6_addr;
485 ip6->ip6_dst = dst ? *dst : in6m->in6m_addr;
487 /* fill in the MLD header */
488 md->m_len = sizeof(struct mld_hdr);
489 mldh = mtod(md, struct mld_hdr *);
490 mldh->mld_type = type;
493 /* XXX: we assume the function will not be called for query messages */
494 mldh->mld_maxdelay = 0;
495 mldh->mld_reserved = 0;
496 mldh->mld_addr = in6m->in6m_addr;
497 in6_clearscope(&mldh->mld_addr); /* XXX */
498 mldh->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6, sizeof(struct ip6_hdr),
499 sizeof(struct mld_hdr));
501 /* construct multicast option */
502 bzero(&im6o, sizeof(im6o));
503 im6o.im6o_multicast_ifp = ifp;
504 im6o.im6o_multicast_hlim = 1;
507 * Request loopback of the report if we are acting as a multicast
508 * router, so that the process-level routing daemon can hear it.
510 im6o.im6o_multicast_loop = (ip6_mrouter != NULL);
512 /* increment output statictics */
513 icmp6stat.icp6s_outhist[type]++;
515 ip6_output(mh, &ip6_opts, NULL, 0, &im6o, &outif, NULL);
517 icmp6_ifstat_inc(outif, ifs6_out_msg);
519 case MLD_LISTENER_QUERY:
520 icmp6_ifstat_inc(outif, ifs6_out_mldquery);
522 case MLD_LISTENER_REPORT:
523 icmp6_ifstat_inc(outif, ifs6_out_mldreport);
525 case MLD_LISTENER_DONE:
526 icmp6_ifstat_inc(outif, ifs6_out_mlddone);
533 * Add an address to the list of IP6 multicast addresses for a given interface.
534 * Add source addresses to the list also, if upstream router is MLDv2 capable
535 * and the number of source is not 0.
538 in6_addmulti(struct in6_addr *maddr6, struct ifnet *ifp,
539 int *errorp, int delay)
541 struct in6_multi *in6m;
547 /*IN6_MULTI_LOCK();*/
549 IN6_LOOKUP_MULTI(*maddr6, ifp, in6m);
552 * If we already joined this group, just bump the
553 * refcount and return it.
555 KASSERT(in6m->in6m_refcount >= 1,
556 ("%s: bad refcount %d", __func__, in6m->in6m_refcount));
557 ++in6m->in6m_refcount;
559 struct in6_multi *nin6m;
560 struct ifmultiaddr *ifma;
561 struct sockaddr_in6 sa6;
563 bzero(&sa6, sizeof(sa6));
564 sa6.sin6_family = AF_INET6;
565 sa6.sin6_len = sizeof(struct sockaddr_in6);
566 sa6.sin6_addr = *maddr6;
568 *errorp = if_addmulti(ifp, (struct sockaddr *)&sa6, &ifma);
573 * If ifma->ifma_protospec is null, then if_addmulti() created
574 * a new record. Otherwise, bump refcount, and we are done.
576 if (ifma->ifma_protospec != NULL) {
577 in6m = ifma->ifma_protospec;
578 ++in6m->in6m_refcount;
582 nin6m = malloc(sizeof(*nin6m), M_IP6MADDR, M_NOWAIT | M_ZERO);
584 if_delmulti_ifma(ifma);
588 nin6m->in6m_addr = *maddr6;
589 nin6m->in6m_ifp = ifp;
590 nin6m->in6m_refcount = 1;
591 nin6m->in6m_ifma = ifma;
592 ifma->ifma_protospec = nin6m;
594 nin6m->in6m_timer_ch = malloc(sizeof(*nin6m->in6m_timer_ch),
595 M_IP6MADDR, M_NOWAIT);
596 if (nin6m->in6m_timer_ch == NULL) {
597 free(nin6m, M_IP6MADDR);
598 if_delmulti_ifma(ifma);
602 LIST_INSERT_HEAD(&in6_multihead, nin6m, in6m_entry);
604 callout_init(nin6m->in6m_timer_ch, 0);
605 nin6m->in6m_timer = delay;
606 if (nin6m->in6m_timer > 0) {
607 nin6m->in6m_state = MLD_REPORTPENDING;
608 mld_starttimer(nin6m);
611 mld6_start_listening(nin6m);
617 /*IN6_MULTI_UNLOCK();*/
618 IFF_UNLOCKGIANT(ifp);
624 * Delete a multicast address record.
626 * TODO: Locking, as per netinet.
629 in6_delmulti(struct in6_multi *in6m)
631 struct ifmultiaddr *ifma;
633 KASSERT(in6m->in6m_refcount >= 1, ("%s: freeing freed in6m", __func__));
635 if (--in6m->in6m_refcount == 0) {
637 mld6_stop_listening(in6m);
639 ifma = in6m->in6m_ifma;
640 KASSERT(ifma->ifma_protospec == in6m,
641 ("%s: ifma_protospec != in6m", __func__));
642 ifma->ifma_protospec = NULL;
644 LIST_REMOVE(in6m, in6m_entry);
645 free(in6m->in6m_timer_ch, M_IP6MADDR);
646 free(in6m, M_IP6MADDR);
648 if_delmulti_ifma(ifma);