1 /* $FreeBSD: src/sys/netinet6/mld6.c,v 1.4.2.4 2003/01/23 21:06:47 sam Exp $ */
2 /* $KAME: mld6.c,v 1.27 2001/04/04 05:17:30 itojun Exp $ */
5 * Copyright (C) 1998 WIDE Project.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * Copyright (c) 1988 Stephen Deering.
35 * Copyright (c) 1992, 1993
36 * The Regents of the University of California. All rights reserved.
38 * This code is derived from software contributed to Berkeley by
39 * Stephen Deering of Stanford University.
41 * Redistribution and use in source and binary forms, with or without
42 * modification, are permitted provided that the following conditions
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.
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
65 * @(#)igmp.c 8.1 (Berkeley) 7/19/93
69 #include "opt_inet6.h"
71 #include <sys/param.h>
72 #include <sys/systm.h>
74 #include <sys/socket.h>
75 #include <sys/protosw.h>
76 #include <sys/syslog.h>
80 #include <netinet/in.h>
81 #include <netinet/in_var.h>
82 #include <netinet/ip6.h>
83 #include <netinet6/ip6_var.h>
84 #include <netinet/icmp6.h>
85 #include <netinet6/mld6_var.h>
87 #include <net/net_osdep.h>
93 /* denotes that the MLD max response delay field specifies time in milliseconds */
94 #define MLD6_TIMER_SCALE 1000
96 * time between repetitions of a node's initial report of interest in a
97 * multicast address(in seconds)
99 #define MLD6_UNSOLICITED_REPORT_INTERVAL 10
101 static struct ip6_pktopts ip6_opts;
102 static int mld6_timers_are_running;
103 /* XXX: These are necessary for KAME's link-local hack */
104 static struct in6_addr mld6_all_nodes_linklocal = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
105 static struct in6_addr mld6_all_routers_linklocal = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
107 static void mld6_sendpkt(struct in6_multi *, int, const struct in6_addr *);
109 static struct lwkt_token mld6_token = LWKT_TOKEN_INITIALIZER(mp_token);
115 static u_int8_t hbh_buf[8];
116 struct ip6_hbh *hbh = (struct ip6_hbh *)hbh_buf;
117 u_int16_t rtalert_code = htons((u_int16_t)IP6OPT_RTALERT_MLD);
119 mld6_timers_are_running = 0;
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_RTALERT;
128 hbh_buf[5] = IP6OPT_RTALERT_LEN - 2;
129 bcopy((caddr_t)&rtalert_code, &hbh_buf[6], sizeof(u_int16_t));
131 init_ip6pktopts(&ip6_opts);
132 ip6_opts.ip6po_hbh = hbh;
136 mld6_start_listening(struct in6_multi *in6m)
140 * The node never sends a Report or Done for the link-scope all-nodes
142 * MLD messages are never sent for multicast addresses whose scope is 0
143 * (reserved) or 1 (node-local).
145 lwkt_gettoken(&mld6_token);
146 mld6_all_nodes_linklocal.s6_addr16[1] =
147 htons(in6m->in6m_ifp->if_index); /* XXX */
148 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld6_all_nodes_linklocal) ||
149 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < IPV6_ADDR_SCOPE_LINKLOCAL) {
150 in6m->in6m_timer = 0;
151 in6m->in6m_state = MLD6_OTHERLISTENER;
153 mld6_sendpkt(in6m, MLD_LISTENER_REPORT, NULL);
154 in6m->in6m_timer = MLD6_RANDOM_DELAY(
155 MLD6_UNSOLICITED_REPORT_INTERVAL * PR_FASTHZ);
156 in6m->in6m_state = MLD6_IREPORTEDLAST;
157 mld6_timers_are_running = 1;
159 lwkt_reltoken(&mld6_token);
163 mld6_stop_listening(struct in6_multi *in6m)
165 mld6_all_nodes_linklocal.s6_addr16[1] =
166 htons(in6m->in6m_ifp->if_index); /* XXX */
167 mld6_all_routers_linklocal.s6_addr16[1] =
168 htons(in6m->in6m_ifp->if_index); /* XXX: necessary when mrouting */
170 if (in6m->in6m_state == MLD6_IREPORTEDLAST &&
171 (!IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld6_all_nodes_linklocal)) &&
172 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) > IPV6_ADDR_SCOPE_INTFACELOCAL)
173 mld6_sendpkt(in6m, MLD_LISTENER_DONE,
174 &mld6_all_routers_linklocal);
178 mld6_input(struct mbuf *m, int off)
181 struct mld_hdr *mldh;
182 struct ifnet *ifp = m->m_pkthdr.rcvif;
183 struct in6_multi *in6m;
184 struct in6_ifaddr *ia;
185 struct ifmultiaddr *ifma, mark;
187 int timer; /* timer value in the MLD query header */
189 #ifndef PULLDOWN_TEST
190 IP6_EXTHDR_CHECK(m, off, sizeof(*mldh),);
191 mldh = (struct mld_hdr *)(mtod(m, caddr_t) + off);
193 IP6_EXTHDR_GET(mldh, struct mld_hdr *, m, off, sizeof(*mldh));
195 icmp6stat.icp6s_tooshort++;
200 lwkt_gettoken(&mld6_token);
201 /* source address validation */
202 ip6 = mtod(m, struct ip6_hdr *); /* in case mpullup */
203 if (!IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) {
206 "mld6_input: src %s is not link-local (grp=%s)\n",
207 ip6_sprintf(&ip6->ip6_src),
208 ip6_sprintf(&mldh->mld_addr));
211 * spec (RFC2710) does not explicitly
212 * specify to discard the packet from a non link-local
213 * source address. But we believe it's expected to do so.
214 * XXX: do we have to allow :: as source?
217 lwkt_reltoken(&mld6_token);
222 * In the MLD6 specification, there are 3 states and a flag.
224 * In Non-Listener state, we simply don't have a membership record.
225 * In Delaying Listener state, our timer is running (in6m->in6m_timer)
226 * In Idle Listener state, our timer is not running (in6m->in6m_timer==0)
228 * The flag is in6m->in6m_state, it is set to MLD6_OTHERLISTENER if
229 * we have heard a report from another member, or MLD6_IREPORTEDLAST
230 * if we sent the last report.
232 switch(mldh->mld_type) {
233 case MLD_LISTENER_QUERY:
234 if (ifp->if_flags & IFF_LOOPBACK)
237 if (!IN6_IS_ADDR_UNSPECIFIED(&mldh->mld_addr) &&
238 !IN6_IS_ADDR_MULTICAST(&mldh->mld_addr))
239 break; /* print error or log stat? */
240 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr))
241 mldh->mld_addr.s6_addr16[1] =
242 htons(ifp->if_index); /* XXX */
245 * - Start the timers in all of our membership records
246 * that the query applies to for the interface on
247 * which the query arrived excl. those that belong
248 * to the "all-nodes" group (ff02::1).
249 * - Restart any timer that is already running but has
250 * A value longer than the requested timeout.
251 * - Use the value specified in the query message as
252 * the maximum timeout.
259 * XXX: System timer resolution is too low to handle Max
260 * Response Delay, so set 1 to the internal timer even if
261 * the calculated value equals to zero when Max Response
264 timer = ntohs(mldh->mld_maxdelay) * PR_FASTHZ /
266 if (timer == 0 && mldh->mld_maxdelay)
268 mld6_all_nodes_linklocal.s6_addr16[1] =
269 htons(ifp->if_index); /* XXX */
271 bzero(&sa, sizeof(sa));
272 sa.sa_family = AF_UNSPEC;
273 sa.sa_len = sizeof(sa);
275 bzero(&mark, sizeof(mark));
276 mark.ifma_addr = &sa;
278 /* TODO: need ifnet_serialize_main */
279 ifnet_serialize_all(ifp);
281 TAILQ_INSERT_HEAD(&ifp->if_multiaddrs, &mark, ifma_link);
282 while ((ifma = TAILQ_NEXT(&mark, ifma_link)) != NULL) {
283 TAILQ_REMOVE(&ifp->if_multiaddrs, &mark, ifma_link);
284 TAILQ_INSERT_AFTER(&ifp->if_multiaddrs, ifma, &mark,
287 if (ifma->ifma_addr->sa_family != AF_INET6)
289 in6m = (struct in6_multi *)ifma->ifma_protospec;
291 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr,
292 &mld6_all_nodes_linklocal) ||
293 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) <
294 IPV6_ADDR_SCOPE_LINKLOCAL)
297 if (IN6_IS_ADDR_UNSPECIFIED(&mldh->mld_addr) ||
298 IN6_ARE_ADDR_EQUAL(&mldh->mld_addr,
303 * Release serializer(s) temporarily,
304 * before sending report.
306 ifnet_deserialize_all(ifp);
307 /* send a report immediately */
308 mld6_sendpkt(in6m, MLD_LISTENER_REPORT,
310 ifnet_serialize_all(ifp);
311 in6m->in6m_timer = 0; /* reset timer */
312 in6m->in6m_state = MLD6_IREPORTEDLAST;
314 else if (in6m->in6m_timer == 0 || /*idle state*/
315 in6m->in6m_timer > timer) {
317 MLD6_RANDOM_DELAY(timer);
318 mld6_timers_are_running = 1;
322 TAILQ_REMOVE(&ifp->if_multiaddrs, &mark, ifma_link);
324 ifnet_deserialize_all(ifp);
326 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr))
327 mldh->mld_addr.s6_addr16[1] = 0; /* XXX */
330 case MLD_LISTENER_REPORT:
332 * For fast leave to work, we have to know that we are the
333 * last person to send a report for this group. Reports
334 * can potentially get looped back if we are a multicast
335 * router, so discard reports sourced by me.
336 * Note that it is impossible to check IFF_LOOPBACK flag of
337 * ifp for this purpose, since ip6_mloopback pass the physical
338 * interface to looutput.
340 if (m->m_flags & M_LOOP) /* XXX: grotty flag, but efficient */
343 if (!IN6_IS_ADDR_MULTICAST(&mldh->mld_addr))
346 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr))
347 mldh->mld_addr.s6_addr16[1] =
348 htons(ifp->if_index); /* XXX */
350 * If we belong to the group being reported, stop
351 * our timer for that group.
353 in6m = IN6_LOOKUP_MULTI(&mldh->mld_addr, ifp);
355 in6m->in6m_timer = 0; /* transit to idle state */
356 in6m->in6m_state = MLD6_OTHERLISTENER; /* clear flag */
359 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr))
360 mldh->mld_addr.s6_addr16[1] = 0; /* XXX */
362 default: /* this is impossible */
363 log(LOG_ERR, "mld6_input: illegal type(%d)", mldh->mld_type);
368 lwkt_reltoken(&mld6_token);
374 struct in6_multi *in6m;
375 struct in6_multistep step;
378 * Quick check to see if any work needs to be done, in order
379 * to minimize the overhead of fasttimo processing.
381 lwkt_gettoken(&mld6_token);
383 if (!mld6_timers_are_running) {
384 lwkt_reltoken(&mld6_token);
388 mld6_timers_are_running = 0;
389 IN6_FIRST_MULTI(step, in6m);
390 while (in6m != NULL) {
391 if (in6m->in6m_timer == 0) {
393 } else if (--in6m->in6m_timer == 0) {
394 mld6_sendpkt(in6m, MLD_LISTENER_REPORT, NULL);
395 in6m->in6m_state = MLD6_IREPORTEDLAST;
397 mld6_timers_are_running = 1;
399 IN6_NEXT_MULTI(step, in6m);
402 lwkt_reltoken(&mld6_token);
406 mld6_sendpkt(struct in6_multi *in6m, int type, const struct in6_addr *dst)
408 struct mbuf *mh, *md;
409 struct mld_hdr *mldh;
411 struct ip6_moptions im6o;
412 struct in6_ifaddr *ia;
413 struct ifnet *ifp = in6m->in6m_ifp;
414 struct ifnet *outif = NULL;
417 * At first, find a link local address on the outgoing interface
418 * to use as the source address of the MLD packet.
420 if ((ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST))
425 * Allocate mbufs to store ip6 header and MLD header.
426 * We allocate 2 mbufs and make chain in advance because
427 * it is more convenient when inserting the hop-by-hop option later.
429 MGETHDR(mh, M_NOWAIT, MT_HEADER);
432 MGET(md, M_NOWAIT, MT_DATA);
439 mh->m_pkthdr.rcvif = NULL;
440 mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld_hdr);
441 mh->m_len = sizeof(struct ip6_hdr);
442 MH_ALIGN(mh, sizeof(struct ip6_hdr));
444 /* fill in the ip6 header */
445 ip6 = mtod(mh, struct ip6_hdr *);
447 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
448 ip6->ip6_vfc |= IPV6_VERSION;
449 /* ip6_plen will be set later */
450 ip6->ip6_nxt = IPPROTO_ICMPV6;
451 /* ip6_hlim will be set by im6o.im6o_multicast_hlim */
452 ip6->ip6_src = ia->ia_addr.sin6_addr;
453 ip6->ip6_dst = dst ? *dst : in6m->in6m_addr;
455 /* fill in the MLD header */
456 md->m_len = sizeof(struct mld_hdr);
457 mldh = mtod(md, struct mld_hdr *);
458 mldh->mld_type = type;
461 /* XXX: we assume the function will not be called for query messages */
462 mldh->mld_maxdelay = 0;
463 mldh->mld_reserved = 0;
464 mldh->mld_addr = in6m->in6m_addr;
465 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr))
466 mldh->mld_addr.s6_addr16[1] = 0; /* XXX */
467 mldh->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6, sizeof(struct ip6_hdr),
468 sizeof(struct mld_hdr));
470 /* construct multicast option */
471 bzero(&im6o, sizeof(im6o));
472 im6o.im6o_multicast_ifp = ifp;
473 im6o.im6o_multicast_hlim = 1;
476 * Request loopback of the report if we are acting as a multicast
477 * router, so that the process-level routing daemon can hear it.
479 im6o.im6o_multicast_loop = (ip6_mrouter != NULL);
481 /* increment output statictics */
482 icmp6stat.icp6s_outhist[type]++;
484 ip6_output(mh, &ip6_opts, NULL, 0, &im6o, &outif, NULL);
486 icmp6_ifstat_inc(outif, ifs6_out_msg);
488 case MLD_LISTENER_QUERY:
489 icmp6_ifstat_inc(outif, ifs6_out_mldquery);
491 case MLD_LISTENER_REPORT:
492 icmp6_ifstat_inc(outif, ifs6_out_mldreport);
494 case MLD_LISTENER_DONE:
495 icmp6_ifstat_inc(outif, ifs6_out_mlddone);