2/* $KAME: mld6.c,v 1.27 2001/04/04 05:17:30 itojun Exp $ */
3
4/*
5 * Copyright (C) 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
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.
19 *
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
30 * SUCH DAMAGE.
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. All advertising materials mentioning features or use of this software
50 * must display the following acknowledgement:
51 * This product includes software developed by the University of
52 * California, Berkeley and its contributors.
53 * 4. Neither the name of the University nor the names of its contributors
54 * may be used to endorse or promote products derived from this software
55 * without specific prior written permission.
56 *
57 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
58 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
59 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
60 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
61 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
62 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
63 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
64 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
65 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
66 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
67 * SUCH DAMAGE.
68 *
69 * @(#)igmp.c 8.1 (Berkeley) 7/19/93
70 */
71
72#include "opt_inet.h"
73#include "opt_inet6.h"
74
75#include <sys/param.h>
76#include <sys/systm.h>
77#include <sys/mbuf.h>
78#include <sys/socket.h>
79#include <sys/protosw.h>
80#include <sys/syslog.h>
81
82#include <net/if.h>
83
84#include <netinet/in.h>
85#include <netinet/in_var.h>
86#include <netinet/ip6.h>
87#include <netinet6/ip6_var.h>
88#include <netinet/icmp6.h>
89#include <netinet6/mld6_var.h>
90
91#include <net/net_osdep.h>
92
93/*
94 * Protocol constants
95 */
96
97/* denotes that the MLD max response delay field specifies time in milliseconds */
98#define MLD6_TIMER_SCALE 1000
99/*
100 * time between repetitions of a node's initial report of interest in a
101 * multicast address(in seconds)
102 */
103#define MLD6_UNSOLICITED_REPORT_INTERVAL 10
104
105static struct ip6_pktopts ip6_opts;
106static int mld6_timers_are_running;
107/* XXX: These are necessary for KAME's link-local hack */
108static struct in6_addr mld6_all_nodes_linklocal = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
109static struct in6_addr mld6_all_routers_linklocal = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
110
111static void mld6_sendpkt __P((struct in6_multi *, int, const struct in6_addr *));
112
113void
114mld6_init()
115{
116 static u_int8_t hbh_buf[8];
117 struct ip6_hbh *hbh = (struct ip6_hbh *)hbh_buf;
118 u_int16_t rtalert_code = htons((u_int16_t)IP6OPT_RTALERT_MLD);
119
120 mld6_timers_are_running = 0;
121
122 /* ip6h_nxt will be fill in later */
123 hbh->ip6h_len = 0; /* (8 >> 3) - 1 */
124
125 /* XXX: grotty hard coding... */
126 hbh_buf[2] = IP6OPT_PADN; /* 2 byte padding */
127 hbh_buf[3] = 0;
128 hbh_buf[4] = IP6OPT_RTALERT;
129 hbh_buf[5] = IP6OPT_RTALERT_LEN - 2;
130 bcopy((caddr_t)&rtalert_code, &hbh_buf[6], sizeof(u_int16_t));
131
132 init_ip6pktopts(&ip6_opts);
133 ip6_opts.ip6po_hbh = hbh;
134}
135
136void
137mld6_start_listening(in6m)
138 struct in6_multi *in6m;
139{
140 int s = splnet();
141
142 /*
143 * RFC2710 page 10:
144 * The node never sends a Report or Done for the link-scope all-nodes
145 * address.
146 * MLD messages are never sent for multicast addresses whose scope is 0
147 * (reserved) or 1 (node-local).
148 */
149 mld6_all_nodes_linklocal.s6_addr16[1] =
150 htons(in6m->in6m_ifp->if_index); /* XXX */
151 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld6_all_nodes_linklocal) ||
152 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < IPV6_ADDR_SCOPE_LINKLOCAL) {
153 in6m->in6m_timer = 0;
154 in6m->in6m_state = MLD6_OTHERLISTENER;
155 } else {
156 mld6_sendpkt(in6m, MLD_LISTENER_REPORT, NULL);
157 in6m->in6m_timer = MLD6_RANDOM_DELAY(
158 MLD6_UNSOLICITED_REPORT_INTERVAL * PR_FASTHZ);
159 in6m->in6m_state = MLD6_IREPORTEDLAST;
160 mld6_timers_are_running = 1;
161 }
162 splx(s);
163}
164
165void
166mld6_stop_listening(in6m)
167 struct in6_multi *in6m;
168{
169 mld6_all_nodes_linklocal.s6_addr16[1] =
170 htons(in6m->in6m_ifp->if_index); /* XXX */
171 mld6_all_routers_linklocal.s6_addr16[1] =
172 htons(in6m->in6m_ifp->if_index); /* XXX: necessary when mrouting */
173
174 if (in6m->in6m_state == MLD6_IREPORTEDLAST &&
175 (!IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld6_all_nodes_linklocal)) &&
176 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) > IPV6_ADDR_SCOPE_NODELOCAL)
177 mld6_sendpkt(in6m, MLD_LISTENER_DONE,
178 &mld6_all_routers_linklocal);
179}
180
181void
182mld6_input(m, off)
183 struct mbuf *m;
184 int off;
185{
186 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
187 struct mld_hdr *mldh;
188 struct ifnet *ifp = m->m_pkthdr.rcvif;
189 struct in6_multi *in6m;
190 struct in6_ifaddr *ia;
191 struct ifmultiaddr *ifma;
192 int timer; /* timer value in the MLD query header */
193
194#ifndef PULLDOWN_TEST
195 IP6_EXTHDR_CHECK(m, off, sizeof(*mldh),);
196 mldh = (struct mld_hdr *)(mtod(m, caddr_t) + off);
197#else
198 IP6_EXTHDR_GET(mldh, struct mld_hdr *, m, off, sizeof(*mldh));
199 if (mldh == NULL) {
200 icmp6stat.icp6s_tooshort++;
201 return;
202 }
203#endif
204
205 /* source address validation */
206 ip6 = mtod(m, struct ip6_hdr *);/* in case mpullup */
207 if (!IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) {
208 log(LOG_ERR,
209 "mld6_input: src %s is not link-local (grp=%s)\n",
210 ip6_sprintf(&ip6->ip6_src),
211 ip6_sprintf(&mldh->mld_addr));
212 /*
213 * spec (RFC2710) does not explicitly
214 * specify to discard the packet from a non link-local
215 * source address. But we believe it's expected to do so.
216 * XXX: do we have to allow :: as source?
217 */
218 m_freem(m);
219 return;
220 }
221
222 /*
223 * In the MLD6 specification, there are 3 states and a flag.
224 *
225 * In Non-Listener state, we simply don't have a membership record.
226 * In Delaying Listener state, our timer is running (in6m->in6m_timer)
227 * In Idle Listener state, our timer is not running (in6m->in6m_timer==0)
228 *
229 * The flag is in6m->in6m_state, it is set to MLD6_OTHERLISTENER if
230 * we have heard a report from another member, or MLD6_IREPORTEDLAST
231 * if we sent the last report.
232 */
233 switch(mldh->mld_type) {
234 case MLD_LISTENER_QUERY:
235 if (ifp->if_flags & IFF_LOOPBACK)
236 break;
237
238 if (!IN6_IS_ADDR_UNSPECIFIED(&mldh->mld_addr) &&
239 !IN6_IS_ADDR_MULTICAST(&mldh->mld_addr))
240 break; /* print error or log stat? */
241 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr))
242 mldh->mld_addr.s6_addr16[1] =
243 htons(ifp->if_index); /* XXX */
244
245 /*
246 * - Start the timers in all of our membership records
247 * that the query applies to for the interface on
248 * which the query arrived excl. those that belong
249 * to the "all-nodes" group (ff02::1).
250 * - Restart any timer that is already running but has
251 * A value longer than the requested timeout.
252 * - Use the value specified in the query message as
253 * the maximum timeout.
254 */
255 IFP_TO_IA6(ifp, ia);
256 if (ia == NULL)
257 break;
258
259 /*
260 * XXX: System timer resolution is too low to handle Max
261 * Response Delay, so set 1 to the internal timer even if
262 * the calculated value equals to zero when Max Response
263 * Delay is positive.
264 */
265 timer = ntohs(mldh->mld_maxdelay)*PR_FASTHZ/MLD6_TIMER_SCALE;
266 if (timer == 0 && mldh->mld_maxdelay)
267 timer = 1;
268 mld6_all_nodes_linklocal.s6_addr16[1] =
269 htons(ifp->if_index); /* XXX */
270
271 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link)
272 {
273 if (ifma->ifma_addr->sa_family != AF_INET6)
274 continue;
275 in6m = (struct in6_multi *)ifma->ifma_protospec;
276 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr,
277 &mld6_all_nodes_linklocal) ||
278 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) <
279 IPV6_ADDR_SCOPE_LINKLOCAL)
280 continue;
281
282 if (IN6_IS_ADDR_UNSPECIFIED(&mldh->mld_addr) ||
283 IN6_ARE_ADDR_EQUAL(&mldh->mld_addr,
284 &in6m->in6m_addr))
285 {
286 if (timer == 0) {
287 /* send a report immediately */
288 mld6_sendpkt(in6m, MLD_LISTENER_REPORT,
289 NULL);
290 in6m->in6m_timer = 0; /* reset timer */
291 in6m->in6m_state = MLD6_IREPORTEDLAST;
292 }
293 else if (in6m->in6m_timer == 0 || /*idle state*/
294 in6m->in6m_timer > timer) {
295 in6m->in6m_timer =
296 MLD6_RANDOM_DELAY(timer);
297 mld6_timers_are_running = 1;
298 }
299 }
300 }
301
302 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr))
303 mldh->mld_addr.s6_addr16[1] = 0; /* XXX */
304 break;
305 case MLD_LISTENER_REPORT:
306 /*
307 * For fast leave to work, we have to know that we are the
308 * last person to send a report for this group. Reports
309 * can potentially get looped back if we are a multicast
310 * router, so discard reports sourced by me.
311 * Note that it is impossible to check IFF_LOOPBACK flag of
312 * ifp for this purpose, since ip6_mloopback pass the physical
313 * interface to looutput.
314 */
315 if (m->m_flags & M_LOOP) /* XXX: grotty flag, but efficient */
316 break;
317
318 if (!IN6_IS_ADDR_MULTICAST(&mldh->mld_addr))
319 break;
320
321 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr))
322 mldh->mld_addr.s6_addr16[1] =
323 htons(ifp->if_index); /* XXX */
324 /*
325 * If we belong to the group being reported, stop
326 * our timer for that group.
327 */
328 IN6_LOOKUP_MULTI(mldh->mld_addr, ifp, in6m);
329 if (in6m) {
330 in6m->in6m_timer = 0; /* transit to idle state */
331 in6m->in6m_state = MLD6_OTHERLISTENER; /* clear flag */
332 }
333
334 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr))
335 mldh->mld_addr.s6_addr16[1] = 0; /* XXX */
336 break;
337 default: /* this is impossible */
338 log(LOG_ERR, "mld6_input: illegal type(%d)", mldh->mld_type);
339 break;
340 }
341
342 m_freem(m);
343}
344
345void
346mld6_fasttimeo()
347{
348 struct in6_multi *in6m;
349 struct in6_multistep step;
350 int s;
351
352 /*
353 * Quick check to see if any work needs to be done, in order
354 * to minimize the overhead of fasttimo processing.
355 */
356 if (!mld6_timers_are_running)
357 return;
358
359 s = splnet();
360 mld6_timers_are_running = 0;
361 IN6_FIRST_MULTI(step, in6m);
362 while (in6m != NULL) {
363 if (in6m->in6m_timer == 0) {
364 /* do nothing */
365 } else if (--in6m->in6m_timer == 0) {
366 mld6_sendpkt(in6m, MLD_LISTENER_REPORT, NULL);
367 in6m->in6m_state = MLD6_IREPORTEDLAST;
368 } else {
369 mld6_timers_are_running = 1;
370 }
371 IN6_NEXT_MULTI(step, in6m);
372 }
373 splx(s);
374}
375
376static void
377mld6_sendpkt(in6m, type, dst)
378 struct in6_multi *in6m;
379 int type;
380 const struct in6_addr *dst;
381{
382 struct mbuf *mh, *md;
383 struct mld_hdr *mldh;
384 struct ip6_hdr *ip6;
385 struct ip6_moptions im6o;
386 struct in6_ifaddr *ia;
387 struct ifnet *ifp = in6m->in6m_ifp;
388 struct ifnet *outif = NULL;
389
390 /*
391 * At first, find a link local address on the outgoing interface
392 * to use as the source address of the MLD packet.
393 */
394 if ((ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST))
395 == NULL)
396 return;
397
398 /*
399 * Allocate mbufs to store ip6 header and MLD header.
400 * We allocate 2 mbufs and make chain in advance because
401 * it is more convenient when inserting the hop-by-hop option later.
402 */
403 MGETHDR(mh, M_DONTWAIT, MT_HEADER);
404 if (mh == NULL)
405 return;
406 MGET(md, M_DONTWAIT, MT_DATA);
407 if (md == NULL) {
408 m_free(mh);
409 return;
410 }
411 mh->m_next = md;
412
413 mh->m_pkthdr.rcvif = NULL;
414 mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld_hdr);
415 mh->m_len = sizeof(struct ip6_hdr);
416 MH_ALIGN(mh, sizeof(struct ip6_hdr));
417
418 /* fill in the ip6 header */
419 ip6 = mtod(mh, struct ip6_hdr *);
420 ip6->ip6_flow = 0;
421 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
422 ip6->ip6_vfc |= IPV6_VERSION;
423 /* ip6_plen will be set later */
424 ip6->ip6_nxt = IPPROTO_ICMPV6;
425 /* ip6_hlim will be set by im6o.im6o_multicast_hlim */
426 ip6->ip6_src = ia->ia_addr.sin6_addr;
427 ip6->ip6_dst = dst ? *dst : in6m->in6m_addr;
428
429 /* fill in the MLD header */
430 md->m_len = sizeof(struct mld_hdr);
431 mldh = mtod(md, struct mld_hdr *);
432 mldh->mld_type = type;
433 mldh->mld_code = 0;
434 mldh->mld_cksum = 0;
435 /* XXX: we assume the function will not be called for query messages */
436 mldh->mld_maxdelay = 0;
437 mldh->mld_reserved = 0;
438 mldh->mld_addr = in6m->in6m_addr;
439 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr))
440 mldh->mld_addr.s6_addr16[1] = 0; /* XXX */
441 mldh->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6,
442 sizeof(struct ip6_hdr),
443 sizeof(struct mld_hdr));
444
445 /* construct multicast option */
446 bzero(&im6o, sizeof(im6o));
447 im6o.im6o_multicast_ifp = ifp;
448 im6o.im6o_multicast_hlim = 1;
449
450 /*
451 * Request loopback of the report if we are acting as a multicast
452 * router, so that the process-level routing daemon can hear it.
453 */
454 im6o.im6o_multicast_loop = (ip6_mrouter != NULL);
455
456 /* increment output statictics */
457 icmp6stat.icp6s_outhist[type]++;
458
| 2/* $KAME: mld6.c,v 1.27 2001/04/04 05:17:30 itojun Exp $ */
3
4/*
5 * Copyright (C) 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
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.
19 *
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
30 * SUCH DAMAGE.
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. All advertising materials mentioning features or use of this software
50 * must display the following acknowledgement:
51 * This product includes software developed by the University of
52 * California, Berkeley and its contributors.
53 * 4. Neither the name of the University nor the names of its contributors
54 * may be used to endorse or promote products derived from this software
55 * without specific prior written permission.
56 *
57 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
58 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
59 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
60 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
61 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
62 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
63 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
64 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
65 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
66 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
67 * SUCH DAMAGE.
68 *
69 * @(#)igmp.c 8.1 (Berkeley) 7/19/93
70 */
71
72#include "opt_inet.h"
73#include "opt_inet6.h"
74
75#include <sys/param.h>
76#include <sys/systm.h>
77#include <sys/mbuf.h>
78#include <sys/socket.h>
79#include <sys/protosw.h>
80#include <sys/syslog.h>
81
82#include <net/if.h>
83
84#include <netinet/in.h>
85#include <netinet/in_var.h>
86#include <netinet/ip6.h>
87#include <netinet6/ip6_var.h>
88#include <netinet/icmp6.h>
89#include <netinet6/mld6_var.h>
90
91#include <net/net_osdep.h>
92
93/*
94 * Protocol constants
95 */
96
97/* denotes that the MLD max response delay field specifies time in milliseconds */
98#define MLD6_TIMER_SCALE 1000
99/*
100 * time between repetitions of a node's initial report of interest in a
101 * multicast address(in seconds)
102 */
103#define MLD6_UNSOLICITED_REPORT_INTERVAL 10
104
105static struct ip6_pktopts ip6_opts;
106static int mld6_timers_are_running;
107/* XXX: These are necessary for KAME's link-local hack */
108static struct in6_addr mld6_all_nodes_linklocal = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
109static struct in6_addr mld6_all_routers_linklocal = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
110
111static void mld6_sendpkt __P((struct in6_multi *, int, const struct in6_addr *));
112
113void
114mld6_init()
115{
116 static u_int8_t hbh_buf[8];
117 struct ip6_hbh *hbh = (struct ip6_hbh *)hbh_buf;
118 u_int16_t rtalert_code = htons((u_int16_t)IP6OPT_RTALERT_MLD);
119
120 mld6_timers_are_running = 0;
121
122 /* ip6h_nxt will be fill in later */
123 hbh->ip6h_len = 0; /* (8 >> 3) - 1 */
124
125 /* XXX: grotty hard coding... */
126 hbh_buf[2] = IP6OPT_PADN; /* 2 byte padding */
127 hbh_buf[3] = 0;
128 hbh_buf[4] = IP6OPT_RTALERT;
129 hbh_buf[5] = IP6OPT_RTALERT_LEN - 2;
130 bcopy((caddr_t)&rtalert_code, &hbh_buf[6], sizeof(u_int16_t));
131
132 init_ip6pktopts(&ip6_opts);
133 ip6_opts.ip6po_hbh = hbh;
134}
135
136void
137mld6_start_listening(in6m)
138 struct in6_multi *in6m;
139{
140 int s = splnet();
141
142 /*
143 * RFC2710 page 10:
144 * The node never sends a Report or Done for the link-scope all-nodes
145 * address.
146 * MLD messages are never sent for multicast addresses whose scope is 0
147 * (reserved) or 1 (node-local).
148 */
149 mld6_all_nodes_linklocal.s6_addr16[1] =
150 htons(in6m->in6m_ifp->if_index); /* XXX */
151 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld6_all_nodes_linklocal) ||
152 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < IPV6_ADDR_SCOPE_LINKLOCAL) {
153 in6m->in6m_timer = 0;
154 in6m->in6m_state = MLD6_OTHERLISTENER;
155 } else {
156 mld6_sendpkt(in6m, MLD_LISTENER_REPORT, NULL);
157 in6m->in6m_timer = MLD6_RANDOM_DELAY(
158 MLD6_UNSOLICITED_REPORT_INTERVAL * PR_FASTHZ);
159 in6m->in6m_state = MLD6_IREPORTEDLAST;
160 mld6_timers_are_running = 1;
161 }
162 splx(s);
163}
164
165void
166mld6_stop_listening(in6m)
167 struct in6_multi *in6m;
168{
169 mld6_all_nodes_linklocal.s6_addr16[1] =
170 htons(in6m->in6m_ifp->if_index); /* XXX */
171 mld6_all_routers_linklocal.s6_addr16[1] =
172 htons(in6m->in6m_ifp->if_index); /* XXX: necessary when mrouting */
173
174 if (in6m->in6m_state == MLD6_IREPORTEDLAST &&
175 (!IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld6_all_nodes_linklocal)) &&
176 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) > IPV6_ADDR_SCOPE_NODELOCAL)
177 mld6_sendpkt(in6m, MLD_LISTENER_DONE,
178 &mld6_all_routers_linklocal);
179}
180
181void
182mld6_input(m, off)
183 struct mbuf *m;
184 int off;
185{
186 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
187 struct mld_hdr *mldh;
188 struct ifnet *ifp = m->m_pkthdr.rcvif;
189 struct in6_multi *in6m;
190 struct in6_ifaddr *ia;
191 struct ifmultiaddr *ifma;
192 int timer; /* timer value in the MLD query header */
193
194#ifndef PULLDOWN_TEST
195 IP6_EXTHDR_CHECK(m, off, sizeof(*mldh),);
196 mldh = (struct mld_hdr *)(mtod(m, caddr_t) + off);
197#else
198 IP6_EXTHDR_GET(mldh, struct mld_hdr *, m, off, sizeof(*mldh));
199 if (mldh == NULL) {
200 icmp6stat.icp6s_tooshort++;
201 return;
202 }
203#endif
204
205 /* source address validation */
206 ip6 = mtod(m, struct ip6_hdr *);/* in case mpullup */
207 if (!IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) {
208 log(LOG_ERR,
209 "mld6_input: src %s is not link-local (grp=%s)\n",
210 ip6_sprintf(&ip6->ip6_src),
211 ip6_sprintf(&mldh->mld_addr));
212 /*
213 * spec (RFC2710) does not explicitly
214 * specify to discard the packet from a non link-local
215 * source address. But we believe it's expected to do so.
216 * XXX: do we have to allow :: as source?
217 */
218 m_freem(m);
219 return;
220 }
221
222 /*
223 * In the MLD6 specification, there are 3 states and a flag.
224 *
225 * In Non-Listener state, we simply don't have a membership record.
226 * In Delaying Listener state, our timer is running (in6m->in6m_timer)
227 * In Idle Listener state, our timer is not running (in6m->in6m_timer==0)
228 *
229 * The flag is in6m->in6m_state, it is set to MLD6_OTHERLISTENER if
230 * we have heard a report from another member, or MLD6_IREPORTEDLAST
231 * if we sent the last report.
232 */
233 switch(mldh->mld_type) {
234 case MLD_LISTENER_QUERY:
235 if (ifp->if_flags & IFF_LOOPBACK)
236 break;
237
238 if (!IN6_IS_ADDR_UNSPECIFIED(&mldh->mld_addr) &&
239 !IN6_IS_ADDR_MULTICAST(&mldh->mld_addr))
240 break; /* print error or log stat? */
241 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr))
242 mldh->mld_addr.s6_addr16[1] =
243 htons(ifp->if_index); /* XXX */
244
245 /*
246 * - Start the timers in all of our membership records
247 * that the query applies to for the interface on
248 * which the query arrived excl. those that belong
249 * to the "all-nodes" group (ff02::1).
250 * - Restart any timer that is already running but has
251 * A value longer than the requested timeout.
252 * - Use the value specified in the query message as
253 * the maximum timeout.
254 */
255 IFP_TO_IA6(ifp, ia);
256 if (ia == NULL)
257 break;
258
259 /*
260 * XXX: System timer resolution is too low to handle Max
261 * Response Delay, so set 1 to the internal timer even if
262 * the calculated value equals to zero when Max Response
263 * Delay is positive.
264 */
265 timer = ntohs(mldh->mld_maxdelay)*PR_FASTHZ/MLD6_TIMER_SCALE;
266 if (timer == 0 && mldh->mld_maxdelay)
267 timer = 1;
268 mld6_all_nodes_linklocal.s6_addr16[1] =
269 htons(ifp->if_index); /* XXX */
270
271 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link)
272 {
273 if (ifma->ifma_addr->sa_family != AF_INET6)
274 continue;
275 in6m = (struct in6_multi *)ifma->ifma_protospec;
276 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr,
277 &mld6_all_nodes_linklocal) ||
278 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) <
279 IPV6_ADDR_SCOPE_LINKLOCAL)
280 continue;
281
282 if (IN6_IS_ADDR_UNSPECIFIED(&mldh->mld_addr) ||
283 IN6_ARE_ADDR_EQUAL(&mldh->mld_addr,
284 &in6m->in6m_addr))
285 {
286 if (timer == 0) {
287 /* send a report immediately */
288 mld6_sendpkt(in6m, MLD_LISTENER_REPORT,
289 NULL);
290 in6m->in6m_timer = 0; /* reset timer */
291 in6m->in6m_state = MLD6_IREPORTEDLAST;
292 }
293 else if (in6m->in6m_timer == 0 || /*idle state*/
294 in6m->in6m_timer > timer) {
295 in6m->in6m_timer =
296 MLD6_RANDOM_DELAY(timer);
297 mld6_timers_are_running = 1;
298 }
299 }
300 }
301
302 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr))
303 mldh->mld_addr.s6_addr16[1] = 0; /* XXX */
304 break;
305 case MLD_LISTENER_REPORT:
306 /*
307 * For fast leave to work, we have to know that we are the
308 * last person to send a report for this group. Reports
309 * can potentially get looped back if we are a multicast
310 * router, so discard reports sourced by me.
311 * Note that it is impossible to check IFF_LOOPBACK flag of
312 * ifp for this purpose, since ip6_mloopback pass the physical
313 * interface to looutput.
314 */
315 if (m->m_flags & M_LOOP) /* XXX: grotty flag, but efficient */
316 break;
317
318 if (!IN6_IS_ADDR_MULTICAST(&mldh->mld_addr))
319 break;
320
321 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr))
322 mldh->mld_addr.s6_addr16[1] =
323 htons(ifp->if_index); /* XXX */
324 /*
325 * If we belong to the group being reported, stop
326 * our timer for that group.
327 */
328 IN6_LOOKUP_MULTI(mldh->mld_addr, ifp, in6m);
329 if (in6m) {
330 in6m->in6m_timer = 0; /* transit to idle state */
331 in6m->in6m_state = MLD6_OTHERLISTENER; /* clear flag */
332 }
333
334 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr))
335 mldh->mld_addr.s6_addr16[1] = 0; /* XXX */
336 break;
337 default: /* this is impossible */
338 log(LOG_ERR, "mld6_input: illegal type(%d)", mldh->mld_type);
339 break;
340 }
341
342 m_freem(m);
343}
344
345void
346mld6_fasttimeo()
347{
348 struct in6_multi *in6m;
349 struct in6_multistep step;
350 int s;
351
352 /*
353 * Quick check to see if any work needs to be done, in order
354 * to minimize the overhead of fasttimo processing.
355 */
356 if (!mld6_timers_are_running)
357 return;
358
359 s = splnet();
360 mld6_timers_are_running = 0;
361 IN6_FIRST_MULTI(step, in6m);
362 while (in6m != NULL) {
363 if (in6m->in6m_timer == 0) {
364 /* do nothing */
365 } else if (--in6m->in6m_timer == 0) {
366 mld6_sendpkt(in6m, MLD_LISTENER_REPORT, NULL);
367 in6m->in6m_state = MLD6_IREPORTEDLAST;
368 } else {
369 mld6_timers_are_running = 1;
370 }
371 IN6_NEXT_MULTI(step, in6m);
372 }
373 splx(s);
374}
375
376static void
377mld6_sendpkt(in6m, type, dst)
378 struct in6_multi *in6m;
379 int type;
380 const struct in6_addr *dst;
381{
382 struct mbuf *mh, *md;
383 struct mld_hdr *mldh;
384 struct ip6_hdr *ip6;
385 struct ip6_moptions im6o;
386 struct in6_ifaddr *ia;
387 struct ifnet *ifp = in6m->in6m_ifp;
388 struct ifnet *outif = NULL;
389
390 /*
391 * At first, find a link local address on the outgoing interface
392 * to use as the source address of the MLD packet.
393 */
394 if ((ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST))
395 == NULL)
396 return;
397
398 /*
399 * Allocate mbufs to store ip6 header and MLD header.
400 * We allocate 2 mbufs and make chain in advance because
401 * it is more convenient when inserting the hop-by-hop option later.
402 */
403 MGETHDR(mh, M_DONTWAIT, MT_HEADER);
404 if (mh == NULL)
405 return;
406 MGET(md, M_DONTWAIT, MT_DATA);
407 if (md == NULL) {
408 m_free(mh);
409 return;
410 }
411 mh->m_next = md;
412
413 mh->m_pkthdr.rcvif = NULL;
414 mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld_hdr);
415 mh->m_len = sizeof(struct ip6_hdr);
416 MH_ALIGN(mh, sizeof(struct ip6_hdr));
417
418 /* fill in the ip6 header */
419 ip6 = mtod(mh, struct ip6_hdr *);
420 ip6->ip6_flow = 0;
421 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
422 ip6->ip6_vfc |= IPV6_VERSION;
423 /* ip6_plen will be set later */
424 ip6->ip6_nxt = IPPROTO_ICMPV6;
425 /* ip6_hlim will be set by im6o.im6o_multicast_hlim */
426 ip6->ip6_src = ia->ia_addr.sin6_addr;
427 ip6->ip6_dst = dst ? *dst : in6m->in6m_addr;
428
429 /* fill in the MLD header */
430 md->m_len = sizeof(struct mld_hdr);
431 mldh = mtod(md, struct mld_hdr *);
432 mldh->mld_type = type;
433 mldh->mld_code = 0;
434 mldh->mld_cksum = 0;
435 /* XXX: we assume the function will not be called for query messages */
436 mldh->mld_maxdelay = 0;
437 mldh->mld_reserved = 0;
438 mldh->mld_addr = in6m->in6m_addr;
439 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr))
440 mldh->mld_addr.s6_addr16[1] = 0; /* XXX */
441 mldh->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6,
442 sizeof(struct ip6_hdr),
443 sizeof(struct mld_hdr));
444
445 /* construct multicast option */
446 bzero(&im6o, sizeof(im6o));
447 im6o.im6o_multicast_ifp = ifp;
448 im6o.im6o_multicast_hlim = 1;
449
450 /*
451 * Request loopback of the report if we are acting as a multicast
452 * router, so that the process-level routing daemon can hear it.
453 */
454 im6o.im6o_multicast_loop = (ip6_mrouter != NULL);
455
456 /* increment output statictics */
457 icmp6stat.icp6s_outhist[type]++;
458
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