in.c revision 1.40 1 /* $NetBSD: in.c,v 1.40 1998/05/29 15:34:24 matt Exp $ */
2
3 /*-
4 * Copyright (c) 1998 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Public Access Networks Corporation ("Panix"). It was developed under
9 * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the NetBSD
22 * Foundation, Inc. and its contributors.
23 * 4. Neither the name of The NetBSD Foundation nor the names of its
24 * contributors may be used to endorse or promote products derived
25 * from this software without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 * POSSIBILITY OF SUCH DAMAGE.
38 */
39
40 /*
41 * Copyright (c) 1982, 1986, 1991, 1993
42 * The Regents of the University of California. All rights reserved.
43 *
44 * Redistribution and use in source and binary forms, with or without
45 * modification, are permitted provided that the following conditions
46 * are met:
47 * 1. Redistributions of source code must retain the above copyright
48 * notice, this list of conditions and the following disclaimer.
49 * 2. Redistributions in binary form must reproduce the above copyright
50 * notice, this list of conditions and the following disclaimer in the
51 * documentation and/or other materials provided with the distribution.
52 * 3. All advertising materials mentioning features or use of this software
53 * must display the following acknowledgement:
54 * This product includes software developed by the University of
55 * California, Berkeley and its contributors.
56 * 4. Neither the name of the University nor the names of its contributors
57 * may be used to endorse or promote products derived from this software
58 * without specific prior written permission.
59 *
60 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
61 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
62 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
63 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
64 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
65 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
66 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
67 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
68 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
69 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
70 * SUCH DAMAGE.
71 *
72 * @(#)in.c 8.4 (Berkeley) 1/9/95
73 */
74
75 #include "opt_mrouting.h"
76
77 #include <sys/param.h>
78 #include <sys/ioctl.h>
79 #include <sys/errno.h>
80 #include <sys/malloc.h>
81 #include <sys/socket.h>
82 #include <sys/socketvar.h>
83 #include <sys/systm.h>
84 #include <sys/proc.h>
85
86 #include <net/if.h>
87 #include <net/route.h>
88
89 #include <net/if_ether.h>
90
91 #include <netinet/in_systm.h>
92 #include <netinet/in.h>
93 #include <netinet/in_var.h>
94 #include <netinet/if_inarp.h>
95 #include <netinet/ip_mroute.h>
96 #include <netinet/igmp_var.h>
97
98 #include "ether.h"
99
100 #ifdef INET
101
102 #ifndef SUBNETSARELOCAL
103 #define SUBNETSARELOCAL 1
104 #endif
105 int subnetsarelocal = SUBNETSARELOCAL;
106
107 /*
108 * Return 1 if an internet address is for a ``local'' host
109 * (one to which we have a connection). If subnetsarelocal
110 * is true, this includes other subnets of the local net.
111 * Otherwise, it includes only the directly-connected (sub)nets.
112 */
113 int
114 in_localaddr(in)
115 struct in_addr in;
116 {
117 register struct in_ifaddr *ia;
118
119 if (subnetsarelocal) {
120 for (ia = in_ifaddr.tqh_first; ia != 0; ia = ia->ia_list.tqe_next)
121 if ((in.s_addr & ia->ia_netmask) == ia->ia_net)
122 return (1);
123 } else {
124 for (ia = in_ifaddr.tqh_first; ia != 0; ia = ia->ia_list.tqe_next)
125 if ((in.s_addr & ia->ia_subnetmask) == ia->ia_subnet)
126 return (1);
127 }
128 return (0);
129 }
130
131 /*
132 * Determine whether an IP address is in a reserved set of addresses
133 * that may not be forwarded, or whether datagrams to that destination
134 * may be forwarded.
135 */
136 int
137 in_canforward(in)
138 struct in_addr in;
139 {
140 register u_int32_t net;
141
142 if (IN_EXPERIMENTAL(in.s_addr) || IN_MULTICAST(in.s_addr))
143 return (0);
144 if (IN_CLASSA(in.s_addr)) {
145 net = in.s_addr & IN_CLASSA_NET;
146 if (net == 0 || net == htonl(IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
147 return (0);
148 }
149 return (1);
150 }
151
152 /*
153 * Trim a mask in a sockaddr
154 */
155 void
156 in_socktrim(ap)
157 struct sockaddr_in *ap;
158 {
159 register char *cplim = (char *) &ap->sin_addr;
160 register char *cp = (char *) (&ap->sin_addr + 1);
161
162 ap->sin_len = 0;
163 while (--cp >= cplim)
164 if (*cp) {
165 (ap)->sin_len = cp - (char *) (ap) + 1;
166 break;
167 }
168 }
169
170 /*
171 * Routine to take an Internet address and convert into a
172 * "dotted quad" representation for printing.
173 */
174 const char *
175 in_fmtaddr(addr)
176 struct in_addr addr;
177 {
178 static char buf[sizeof("123.456.789.123")];
179
180 addr.s_addr = ntohl(addr.s_addr);
181
182 sprintf(buf, "%d.%d.%d.%d",
183 (addr.s_addr >> 24) & 0xFF,
184 (addr.s_addr >> 16) & 0xFF,
185 (addr.s_addr >> 8) & 0xFF,
186 (addr.s_addr >> 0) & 0xFF);
187 return buf;
188 }
189
190 /*
191 * Maintain the "in_maxmtu" variable, which is the largest
192 * mtu for non-local interfaces with AF_INET addresses assigned
193 * to them that are up.
194 */
195 unsigned long in_maxmtu;
196
197 void
198 in_setmaxmtu()
199 {
200 register struct in_ifaddr *ia;
201 register struct ifnet *ifp;
202 unsigned long maxmtu = 0;
203
204 for (ia = in_ifaddr.tqh_first; ia != 0; ia = ia->ia_list.tqe_next) {
205 if ((ifp = ia->ia_ifp) == 0)
206 continue;
207 if ((ifp->if_flags & (IFF_UP|IFF_LOOPBACK)) != IFF_UP)
208 continue;
209 if (ifp->if_mtu > maxmtu)
210 maxmtu = ifp->if_mtu;
211 }
212 if (maxmtu)
213 in_maxmtu = maxmtu;
214 }
215
216 int in_interfaces; /* number of external internet interfaces */
217
218 /*
219 * Generic internet control operations (ioctl's).
220 * Ifp is 0 if not an interface-specific ioctl.
221 */
222 /* ARGSUSED */
223 int
224 in_control(so, cmd, data, ifp, p)
225 struct socket *so;
226 u_long cmd;
227 caddr_t data;
228 register struct ifnet *ifp;
229 struct proc *p;
230 {
231 register struct ifreq *ifr = (struct ifreq *)data;
232 register struct in_ifaddr *ia = 0;
233 struct in_aliasreq *ifra = (struct in_aliasreq *)data;
234 struct sockaddr_in oldaddr;
235 int error, hostIsNew, maskIsNew;
236
237 /*
238 * Find address for this interface, if it exists.
239 */
240 if (ifp)
241 IFP_TO_IA(ifp, ia);
242
243 switch (cmd) {
244
245 case SIOCAIFADDR:
246 case SIOCDIFADDR:
247 if (ifra->ifra_addr.sin_family == AF_INET)
248 for (ia = IN_IFADDR_HASH(ifra->ifra_addr.sin_addr.s_addr).lh_first;
249 ia != 0; ia = ia->ia_hash.le_next) {
250 if (ia->ia_ifp == ifp &&
251 in_hosteq(ia->ia_addr.sin_addr,
252 ifra->ifra_addr.sin_addr))
253 break;
254 }
255 if (cmd == SIOCDIFADDR && ia == 0)
256 return (EADDRNOTAVAIL);
257 /* FALLTHROUGH */
258 case SIOCSIFADDR:
259 case SIOCSIFNETMASK:
260 case SIOCSIFDSTADDR:
261 if (p == 0 || (error = suser(p->p_ucred, &p->p_acflag)))
262 return (EPERM);
263
264 if (ifp == 0)
265 panic("in_control");
266 if (ia == 0) {
267 MALLOC(ia, struct in_ifaddr *, sizeof(*ia),
268 M_IFADDR, M_WAITOK);
269 if (ia == 0)
270 return (ENOBUFS);
271 bzero((caddr_t)ia, sizeof *ia);
272 TAILQ_INSERT_TAIL(&in_ifaddr, ia, ia_list);
273 TAILQ_INSERT_TAIL(&ifp->if_addrlist, (struct ifaddr *)ia,
274 ifa_list);
275 ia->ia_ifa.ifa_addr = sintosa(&ia->ia_addr);
276 ia->ia_ifa.ifa_dstaddr = sintosa(&ia->ia_dstaddr);
277 ia->ia_ifa.ifa_netmask = sintosa(&ia->ia_sockmask);
278 ia->ia_sockmask.sin_len = 8;
279 if (ifp->if_flags & IFF_BROADCAST) {
280 ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
281 ia->ia_broadaddr.sin_family = AF_INET;
282 }
283 ia->ia_ifp = ifp;
284 LIST_INIT(&ia->ia_multiaddrs);
285 if ((ifp->if_flags & IFF_LOOPBACK) == 0)
286 in_interfaces++;
287 }
288 break;
289
290 case SIOCSIFBRDADDR:
291 if (p == 0 || (error = suser(p->p_ucred, &p->p_acflag)))
292 return (EPERM);
293 /* FALLTHROUGH */
294
295 case SIOCGIFADDR:
296 case SIOCGIFNETMASK:
297 case SIOCGIFDSTADDR:
298 case SIOCGIFBRDADDR:
299 if (ia == 0)
300 return (EADDRNOTAVAIL);
301 break;
302 }
303 switch (cmd) {
304
305 case SIOCGIFADDR:
306 *satosin(&ifr->ifr_addr) = ia->ia_addr;
307 break;
308
309 case SIOCGIFBRDADDR:
310 if ((ifp->if_flags & IFF_BROADCAST) == 0)
311 return (EINVAL);
312 *satosin(&ifr->ifr_dstaddr) = ia->ia_broadaddr;
313 break;
314
315 case SIOCGIFDSTADDR:
316 if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
317 return (EINVAL);
318 *satosin(&ifr->ifr_dstaddr) = ia->ia_dstaddr;
319 break;
320
321 case SIOCGIFNETMASK:
322 *satosin(&ifr->ifr_addr) = ia->ia_sockmask;
323 break;
324
325 case SIOCSIFDSTADDR:
326 if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
327 return (EINVAL);
328 oldaddr = ia->ia_dstaddr;
329 ia->ia_dstaddr = *satosin(&ifr->ifr_dstaddr);
330 if (ifp->if_ioctl && (error = (*ifp->if_ioctl)
331 (ifp, SIOCSIFDSTADDR, (caddr_t)ia))) {
332 ia->ia_dstaddr = oldaddr;
333 return (error);
334 }
335 if (ia->ia_flags & IFA_ROUTE) {
336 ia->ia_ifa.ifa_dstaddr = sintosa(&oldaddr);
337 rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
338 ia->ia_ifa.ifa_dstaddr = sintosa(&ia->ia_dstaddr);
339 rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP);
340 }
341 break;
342
343 case SIOCSIFBRDADDR:
344 if ((ifp->if_flags & IFF_BROADCAST) == 0)
345 return (EINVAL);
346 ia->ia_broadaddr = *satosin(&ifr->ifr_broadaddr);
347 break;
348
349 case SIOCSIFADDR:
350 return (in_ifinit(ifp, ia, satosin(&ifr->ifr_addr), 1));
351
352 case SIOCSIFNETMASK:
353 ia->ia_subnetmask = ia->ia_sockmask.sin_addr.s_addr =
354 ifra->ifra_addr.sin_addr.s_addr;
355 break;
356
357 case SIOCAIFADDR:
358 maskIsNew = 0;
359 hostIsNew = 1;
360 error = 0;
361 if (ia->ia_addr.sin_family == AF_INET) {
362 if (ifra->ifra_addr.sin_len == 0) {
363 ifra->ifra_addr = ia->ia_addr;
364 hostIsNew = 0;
365 } else if (in_hosteq(ia->ia_addr.sin_addr, ifra->ifra_addr.sin_addr))
366 hostIsNew = 0;
367 }
368 if (ifra->ifra_mask.sin_len) {
369 in_ifscrub(ifp, ia);
370 ia->ia_sockmask = ifra->ifra_mask;
371 ia->ia_subnetmask = ia->ia_sockmask.sin_addr.s_addr;
372 maskIsNew = 1;
373 }
374 if ((ifp->if_flags & IFF_POINTOPOINT) &&
375 (ifra->ifra_dstaddr.sin_family == AF_INET)) {
376 in_ifscrub(ifp, ia);
377 ia->ia_dstaddr = ifra->ifra_dstaddr;
378 maskIsNew = 1; /* We lie; but the effect's the same */
379 }
380 if (ifra->ifra_addr.sin_family == AF_INET &&
381 (hostIsNew || maskIsNew))
382 error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
383 if ((ifp->if_flags & IFF_BROADCAST) &&
384 (ifra->ifra_broadaddr.sin_family == AF_INET))
385 ia->ia_broadaddr = ifra->ifra_broadaddr;
386 return (error);
387
388 case SIOCDIFADDR:
389 in_ifscrub(ifp, ia);
390 LIST_REMOVE(ia, ia_hash);
391 TAILQ_REMOVE(&ifp->if_addrlist, (struct ifaddr *)ia, ifa_list);
392 TAILQ_REMOVE(&in_ifaddr, ia, ia_list);
393 IFAFREE((&ia->ia_ifa));
394 in_setmaxmtu();
395 break;
396
397 #ifdef MROUTING
398 case SIOCGETVIFCNT:
399 case SIOCGETSGCNT:
400 return (mrt_ioctl(so, cmd, data));
401 #endif /* MROUTING */
402
403 default:
404 if (ifp == 0 || ifp->if_ioctl == 0)
405 return (EOPNOTSUPP);
406 error = (*ifp->if_ioctl)(ifp, cmd, data);
407 in_setmaxmtu();
408 return(error);
409 }
410 return (0);
411 }
412
413 /*
414 * Delete any existing route for an interface.
415 */
416 void
417 in_ifscrub(ifp, ia)
418 register struct ifnet *ifp;
419 register struct in_ifaddr *ia;
420 {
421
422 if ((ia->ia_flags & IFA_ROUTE) == 0)
423 return;
424 if (ifp->if_flags & (IFF_LOOPBACK|IFF_POINTOPOINT))
425 rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
426 else
427 rtinit(&(ia->ia_ifa), (int)RTM_DELETE, 0);
428 ia->ia_flags &= ~IFA_ROUTE;
429 }
430
431 /*
432 * Initialize an interface's internet address
433 * and routing table entry.
434 */
435 int
436 in_ifinit(ifp, ia, sin, scrub)
437 register struct ifnet *ifp;
438 register struct in_ifaddr *ia;
439 struct sockaddr_in *sin;
440 int scrub;
441 {
442 register u_int32_t i = sin->sin_addr.s_addr;
443 struct sockaddr_in oldaddr;
444 int s = splimp(), flags = RTF_UP, error;
445
446 /*
447 * Set up new addresses.
448 */
449 oldaddr = ia->ia_addr;
450 if (ia->ia_addr.sin_family == AF_INET)
451 LIST_REMOVE(ia, ia_hash);
452 ia->ia_addr = *sin;
453 LIST_INSERT_HEAD(&IN_IFADDR_HASH(ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
454
455 /*
456 * Give the interface a chance to initialize
457 * if this is its first address,
458 * and to validate the address if necessary.
459 */
460 if (ifp->if_ioctl &&
461 (error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia)))
462 goto bad;
463 splx(s);
464 if (scrub) {
465 ia->ia_ifa.ifa_addr = sintosa(&oldaddr);
466 in_ifscrub(ifp, ia);
467 ia->ia_ifa.ifa_addr = sintosa(&ia->ia_addr);
468 }
469
470 if (IN_CLASSA(i))
471 ia->ia_netmask = IN_CLASSA_NET;
472 else if (IN_CLASSB(i))
473 ia->ia_netmask = IN_CLASSB_NET;
474 else
475 ia->ia_netmask = IN_CLASSC_NET;
476 /*
477 * The subnet mask usually includes at least the standard network part,
478 * but may may be smaller in the case of supernetting.
479 * If it is set, we believe it.
480 */
481 if (ia->ia_subnetmask == 0) {
482 ia->ia_subnetmask = ia->ia_netmask;
483 ia->ia_sockmask.sin_addr.s_addr = ia->ia_subnetmask;
484 } else
485 ia->ia_netmask &= ia->ia_subnetmask;
486
487 ia->ia_net = i & ia->ia_netmask;
488 ia->ia_subnet = i & ia->ia_subnetmask;
489 in_socktrim(&ia->ia_sockmask);
490 /* re-calculate the "in_maxmtu" value */
491 in_setmaxmtu();
492 /*
493 * Add route for the network.
494 */
495 ia->ia_ifa.ifa_metric = ifp->if_metric;
496 if (ifp->if_flags & IFF_BROADCAST) {
497 ia->ia_broadaddr.sin_addr.s_addr =
498 ia->ia_subnet | ~ia->ia_subnetmask;
499 ia->ia_netbroadcast.s_addr =
500 ia->ia_net | ~ia->ia_netmask;
501 } else if (ifp->if_flags & IFF_LOOPBACK) {
502 ia->ia_ifa.ifa_dstaddr = ia->ia_ifa.ifa_addr;
503 flags |= RTF_HOST;
504 } else if (ifp->if_flags & IFF_POINTOPOINT) {
505 if (ia->ia_dstaddr.sin_family != AF_INET)
506 return (0);
507 flags |= RTF_HOST;
508 }
509 error = rtinit(&ia->ia_ifa, (int)RTM_ADD, flags);
510 if (!error)
511 ia->ia_flags |= IFA_ROUTE;
512 /*
513 * If the interface supports multicast, join the "all hosts"
514 * multicast group on that interface.
515 */
516 if (ifp->if_flags & IFF_MULTICAST) {
517 struct in_addr addr;
518
519 addr.s_addr = INADDR_ALLHOSTS_GROUP;
520 in_addmulti(&addr, ifp);
521 }
522 return (error);
523 bad:
524 splx(s);
525 LIST_REMOVE(ia, ia_hash);
526 ia->ia_addr = oldaddr;
527 if (ia->ia_addr.sin_family == AF_INET)
528 LIST_INSERT_HEAD(&IN_IFADDR_HASH(ia->ia_addr.sin_addr.s_addr),
529 ia, ia_hash);
530 return (error);
531 }
532
533 /*
534 * Return 1 if the address might be a local broadcast address.
535 */
536 int
537 in_broadcast(in, ifp)
538 struct in_addr in;
539 struct ifnet *ifp;
540 {
541 register struct ifaddr *ifa;
542
543 if (in.s_addr == INADDR_BROADCAST ||
544 in_nullhost(in))
545 return 1;
546 if ((ifp->if_flags & IFF_BROADCAST) == 0)
547 return 0;
548 /*
549 * Look through the list of addresses for a match
550 * with a broadcast address.
551 */
552 #define ia (ifatoia(ifa))
553 for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
554 if (ifa->ifa_addr->sa_family == AF_INET &&
555 (in_hosteq(in, ia->ia_broadaddr.sin_addr) ||
556 in_hosteq(in, ia->ia_netbroadcast) ||
557 /*
558 * Check for old-style (host 0) broadcast.
559 */
560 in.s_addr == ia->ia_subnet ||
561 in.s_addr == ia->ia_net))
562 return 1;
563 return (0);
564 #undef ia
565 }
566
567 /*
568 * Add an address to the list of IP multicast addresses for a given interface.
569 */
570 struct in_multi *
571 in_addmulti(ap, ifp)
572 register struct in_addr *ap;
573 register struct ifnet *ifp;
574 {
575 register struct in_multi *inm;
576 struct ifreq ifr;
577 struct in_ifaddr *ia;
578 int s = splsoftnet();
579
580 /*
581 * See if address already in list.
582 */
583 IN_LOOKUP_MULTI(*ap, ifp, inm);
584 if (inm != NULL) {
585 /*
586 * Found it; just increment the reference count.
587 */
588 ++inm->inm_refcount;
589 } else {
590 /*
591 * New address; allocate a new multicast record
592 * and link it into the interface's multicast list.
593 */
594 inm = (struct in_multi *)malloc(sizeof(*inm),
595 M_IPMADDR, M_NOWAIT);
596 if (inm == NULL) {
597 splx(s);
598 return (NULL);
599 }
600 inm->inm_addr = *ap;
601 inm->inm_ifp = ifp;
602 inm->inm_refcount = 1;
603 IFP_TO_IA(ifp, ia);
604 if (ia == NULL) {
605 free(inm, M_IPMADDR);
606 splx(s);
607 return (NULL);
608 }
609 inm->inm_ia = ia;
610 LIST_INSERT_HEAD(&ia->ia_multiaddrs, inm, inm_list);
611 /*
612 * Ask the network driver to update its multicast reception
613 * filter appropriately for the new address.
614 */
615 satosin(&ifr.ifr_addr)->sin_len = sizeof(struct sockaddr_in);
616 satosin(&ifr.ifr_addr)->sin_family = AF_INET;
617 satosin(&ifr.ifr_addr)->sin_addr = *ap;
618 if ((ifp->if_ioctl == NULL) ||
619 (*ifp->if_ioctl)(ifp, SIOCADDMULTI,(caddr_t)&ifr) != 0) {
620 LIST_REMOVE(inm, inm_list);
621 free(inm, M_IPMADDR);
622 splx(s);
623 return (NULL);
624 }
625 /*
626 * Let IGMP know that we have joined a new IP multicast group.
627 */
628 igmp_joingroup(inm);
629 }
630 splx(s);
631 return (inm);
632 }
633
634 /*
635 * Delete a multicast address record.
636 */
637 void
638 in_delmulti(inm)
639 register struct in_multi *inm;
640 {
641 struct ifreq ifr;
642 int s = splsoftnet();
643
644 if (--inm->inm_refcount == 0) {
645 /*
646 * No remaining claims to this record; let IGMP know that
647 * we are leaving the multicast group.
648 */
649 igmp_leavegroup(inm);
650 /*
651 * Unlink from list.
652 */
653 LIST_REMOVE(inm, inm_list);
654 /*
655 * Notify the network driver to update its multicast reception
656 * filter.
657 */
658 satosin(&ifr.ifr_addr)->sin_family = AF_INET;
659 satosin(&ifr.ifr_addr)->sin_addr = inm->inm_addr;
660 (*inm->inm_ifp->if_ioctl)(inm->inm_ifp, SIOCDELMULTI,
661 (caddr_t)&ifr);
662 free(inm, M_IPMADDR);
663 }
664 splx(s);
665 }
666 #endif
667