FreeBSD/Linux Kernel Cross Reference
sys/netinet/in.c
1 /*
2 * Copyright (c) 1982, 1986, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
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. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 * @(#)in.c 8.4 (Berkeley) 1/9/95
34 * $FreeBSD: releng/5.2/sys/netinet/in.c 121922 2003-11-03 03:22:39Z sam $
35 */
36
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/sockio.h>
40 #include <sys/malloc.h>
41 #include <sys/socket.h>
42 #include <sys/kernel.h>
43 #include <sys/sysctl.h>
44
45 #include <net/if.h>
46 #include <net/if_types.h>
47 #include <net/route.h>
48
49 #include <netinet/in.h>
50 #include <netinet/in_var.h>
51 #include <netinet/in_pcb.h>
52
53 #include <netinet/igmp_var.h>
54
55 static MALLOC_DEFINE(M_IPMADDR, "in_multi", "internet multicast address");
56
57 static int in_mask2len(struct in_addr *);
58 static void in_len2mask(struct in_addr *, int);
59 static int in_lifaddr_ioctl(struct socket *, u_long, caddr_t,
60 struct ifnet *, struct thread *);
61
62 static void in_socktrim(struct sockaddr_in *);
63 static int in_ifinit(struct ifnet *,
64 struct in_ifaddr *, struct sockaddr_in *, int);
65
66 static int subnetsarelocal = 0;
67 SYSCTL_INT(_net_inet_ip, OID_AUTO, subnets_are_local, CTLFLAG_RW,
68 &subnetsarelocal, 0, "");
69
70 struct in_multihead in_multihead; /* XXX BSS initialization */
71
72 extern struct inpcbinfo ripcbinfo;
73 extern struct inpcbinfo udbinfo;
74
75 /*
76 * Return 1 if an internet address is for a ``local'' host
77 * (one to which we have a connection). If subnetsarelocal
78 * is true, this includes other subnets of the local net.
79 * Otherwise, it includes only the directly-connected (sub)nets.
80 */
81 int
82 in_localaddr(in)
83 struct in_addr in;
84 {
85 register u_long i = ntohl(in.s_addr);
86 register struct in_ifaddr *ia;
87
88 if (subnetsarelocal) {
89 TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link)
90 if ((i & ia->ia_netmask) == ia->ia_net)
91 return (1);
92 } else {
93 TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link)
94 if ((i & ia->ia_subnetmask) == ia->ia_subnet)
95 return (1);
96 }
97 return (0);
98 }
99
100 /*
101 * Determine whether an IP address is in a reserved set of addresses
102 * that may not be forwarded, or whether datagrams to that destination
103 * may be forwarded.
104 */
105 int
106 in_canforward(in)
107 struct in_addr in;
108 {
109 register u_long i = ntohl(in.s_addr);
110 register u_long net;
111
112 if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i))
113 return (0);
114 if (IN_CLASSA(i)) {
115 net = i & IN_CLASSA_NET;
116 if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
117 return (0);
118 }
119 return (1);
120 }
121
122 /*
123 * Trim a mask in a sockaddr
124 */
125 static void
126 in_socktrim(ap)
127 struct sockaddr_in *ap;
128 {
129 register char *cplim = (char *) &ap->sin_addr;
130 register char *cp = (char *) (&ap->sin_addr + 1);
131
132 ap->sin_len = 0;
133 while (--cp >= cplim)
134 if (*cp) {
135 (ap)->sin_len = cp - (char *) (ap) + 1;
136 break;
137 }
138 }
139
140 static int
141 in_mask2len(mask)
142 struct in_addr *mask;
143 {
144 int x, y;
145 u_char *p;
146
147 p = (u_char *)mask;
148 for (x = 0; x < sizeof(*mask); x++) {
149 if (p[x] != 0xff)
150 break;
151 }
152 y = 0;
153 if (x < sizeof(*mask)) {
154 for (y = 0; y < 8; y++) {
155 if ((p[x] & (0x80 >> y)) == 0)
156 break;
157 }
158 }
159 return x * 8 + y;
160 }
161
162 static void
163 in_len2mask(mask, len)
164 struct in_addr *mask;
165 int len;
166 {
167 int i;
168 u_char *p;
169
170 p = (u_char *)mask;
171 bzero(mask, sizeof(*mask));
172 for (i = 0; i < len / 8; i++)
173 p[i] = 0xff;
174 if (len % 8)
175 p[i] = (0xff00 >> (len % 8)) & 0xff;
176 }
177
178 /*
179 * Generic internet control operations (ioctl's).
180 * Ifp is 0 if not an interface-specific ioctl.
181 */
182 /* ARGSUSED */
183 int
184 in_control(so, cmd, data, ifp, td)
185 struct socket *so;
186 u_long cmd;
187 caddr_t data;
188 register struct ifnet *ifp;
189 struct thread *td;
190 {
191 register struct ifreq *ifr = (struct ifreq *)data;
192 register struct in_ifaddr *ia = 0, *iap;
193 register struct ifaddr *ifa;
194 struct in_addr dst;
195 struct in_ifaddr *oia;
196 struct in_aliasreq *ifra = (struct in_aliasreq *)data;
197 struct sockaddr_in oldaddr;
198 int error, hostIsNew, iaIsNew, maskIsNew, s;
199
200 iaIsNew = 0;
201
202 switch (cmd) {
203 case SIOCALIFADDR:
204 case SIOCDLIFADDR:
205 if (td && (error = suser(td)) != 0)
206 return error;
207 /*fall through*/
208 case SIOCGLIFADDR:
209 if (!ifp)
210 return EINVAL;
211 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
212 }
213
214 /*
215 * Find address for this interface, if it exists.
216 *
217 * If an alias address was specified, find that one instead of
218 * the first one on the interface, if possible.
219 */
220 if (ifp) {
221 dst = ((struct sockaddr_in *)&ifr->ifr_addr)->sin_addr;
222 LIST_FOREACH(iap, INADDR_HASH(dst.s_addr), ia_hash)
223 if (iap->ia_ifp == ifp &&
224 iap->ia_addr.sin_addr.s_addr == dst.s_addr) {
225 ia = iap;
226 break;
227 }
228 if (ia == NULL)
229 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
230 iap = ifatoia(ifa);
231 if (iap->ia_addr.sin_family == AF_INET) {
232 ia = iap;
233 break;
234 }
235 }
236 }
237
238 switch (cmd) {
239
240 case SIOCAIFADDR:
241 case SIOCDIFADDR:
242 if (ifp == 0)
243 return (EADDRNOTAVAIL);
244 if (ifra->ifra_addr.sin_family == AF_INET) {
245 for (oia = ia; ia; ia = TAILQ_NEXT(ia, ia_link)) {
246 if (ia->ia_ifp == ifp &&
247 ia->ia_addr.sin_addr.s_addr ==
248 ifra->ifra_addr.sin_addr.s_addr)
249 break;
250 }
251 if ((ifp->if_flags & IFF_POINTOPOINT)
252 && (cmd == SIOCAIFADDR)
253 && (ifra->ifra_dstaddr.sin_addr.s_addr
254 == INADDR_ANY)) {
255 return EDESTADDRREQ;
256 }
257 }
258 if (cmd == SIOCDIFADDR && ia == 0)
259 return (EADDRNOTAVAIL);
260 /* FALLTHROUGH */
261 case SIOCSIFADDR:
262 case SIOCSIFNETMASK:
263 case SIOCSIFDSTADDR:
264 if (td && (error = suser(td)) != 0)
265 return error;
266
267 if (ifp == 0)
268 return (EADDRNOTAVAIL);
269 if (ia == (struct in_ifaddr *)0) {
270 ia = (struct in_ifaddr *)
271 malloc(sizeof *ia, M_IFADDR, M_WAITOK | M_ZERO);
272 if (ia == (struct in_ifaddr *)NULL)
273 return (ENOBUFS);
274 /*
275 * Protect from ipintr() traversing address list
276 * while we're modifying it.
277 */
278 s = splnet();
279 TAILQ_INSERT_TAIL(&in_ifaddrhead, ia, ia_link);
280
281 ifa = &ia->ia_ifa;
282 IFA_LOCK_INIT(ifa);
283 ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr;
284 ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
285 ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask;
286 ifa->ifa_refcnt = 1;
287 TAILQ_INSERT_TAIL(&ifp->if_addrhead, ifa, ifa_link);
288
289 ia->ia_sockmask.sin_len = 8;
290 ia->ia_sockmask.sin_family = AF_INET;
291 if (ifp->if_flags & IFF_BROADCAST) {
292 ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
293 ia->ia_broadaddr.sin_family = AF_INET;
294 }
295 ia->ia_ifp = ifp;
296 splx(s);
297 iaIsNew = 1;
298 }
299 break;
300
301 case SIOCSIFBRDADDR:
302 if (td && (error = suser(td)) != 0)
303 return error;
304 /* FALLTHROUGH */
305
306 case SIOCGIFADDR:
307 case SIOCGIFNETMASK:
308 case SIOCGIFDSTADDR:
309 case SIOCGIFBRDADDR:
310 if (ia == (struct in_ifaddr *)0)
311 return (EADDRNOTAVAIL);
312 break;
313 }
314 switch (cmd) {
315
316 case SIOCGIFADDR:
317 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_addr;
318 return (0);
319
320 case SIOCGIFBRDADDR:
321 if ((ifp->if_flags & IFF_BROADCAST) == 0)
322 return (EINVAL);
323 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_broadaddr;
324 return (0);
325
326 case SIOCGIFDSTADDR:
327 if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
328 return (EINVAL);
329 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_dstaddr;
330 return (0);
331
332 case SIOCGIFNETMASK:
333 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_sockmask;
334 return (0);
335
336 case SIOCSIFDSTADDR:
337 if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
338 return (EINVAL);
339 oldaddr = ia->ia_dstaddr;
340 ia->ia_dstaddr = *(struct sockaddr_in *)&ifr->ifr_dstaddr;
341 if (ifp->if_ioctl && (error = (*ifp->if_ioctl)
342 (ifp, SIOCSIFDSTADDR, (caddr_t)ia))) {
343 ia->ia_dstaddr = oldaddr;
344 return (error);
345 }
346 if (ia->ia_flags & IFA_ROUTE) {
347 ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr;
348 rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
349 ia->ia_ifa.ifa_dstaddr =
350 (struct sockaddr *)&ia->ia_dstaddr;
351 rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP);
352 }
353 return (0);
354
355 case SIOCSIFBRDADDR:
356 if ((ifp->if_flags & IFF_BROADCAST) == 0)
357 return (EINVAL);
358 ia->ia_broadaddr = *(struct sockaddr_in *)&ifr->ifr_broadaddr;
359 return (0);
360
361 case SIOCSIFADDR:
362 error = in_ifinit(ifp, ia,
363 (struct sockaddr_in *) &ifr->ifr_addr, 1);
364 if (error != 0 && iaIsNew)
365 break;
366 return (0);
367
368 case SIOCSIFNETMASK:
369 ia->ia_sockmask.sin_addr = ifra->ifra_addr.sin_addr;
370 ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr);
371 return (0);
372
373 case SIOCAIFADDR:
374 maskIsNew = 0;
375 hostIsNew = 1;
376 error = 0;
377 if (ia->ia_addr.sin_family == AF_INET) {
378 if (ifra->ifra_addr.sin_len == 0) {
379 ifra->ifra_addr = ia->ia_addr;
380 hostIsNew = 0;
381 } else if (ifra->ifra_addr.sin_addr.s_addr ==
382 ia->ia_addr.sin_addr.s_addr)
383 hostIsNew = 0;
384 }
385 if (ifra->ifra_mask.sin_len) {
386 in_ifscrub(ifp, ia);
387 ia->ia_sockmask = ifra->ifra_mask;
388 ia->ia_sockmask.sin_family = AF_INET;
389 ia->ia_subnetmask =
390 ntohl(ia->ia_sockmask.sin_addr.s_addr);
391 maskIsNew = 1;
392 }
393 if ((ifp->if_flags & IFF_POINTOPOINT) &&
394 (ifra->ifra_dstaddr.sin_family == AF_INET)) {
395 in_ifscrub(ifp, ia);
396 ia->ia_dstaddr = ifra->ifra_dstaddr;
397 maskIsNew = 1; /* We lie; but the effect's the same */
398 }
399 if (ifra->ifra_addr.sin_family == AF_INET &&
400 (hostIsNew || maskIsNew))
401 error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
402 if (error != 0 && iaIsNew)
403 break;
404
405 if ((ifp->if_flags & IFF_BROADCAST) &&
406 (ifra->ifra_broadaddr.sin_family == AF_INET))
407 ia->ia_broadaddr = ifra->ifra_broadaddr;
408 return (error);
409
410 case SIOCDIFADDR:
411 /*
412 * in_ifscrub kills the interface route.
413 */
414 in_ifscrub(ifp, ia);
415 /*
416 * in_ifadown gets rid of all the rest of
417 * the routes. This is not quite the right
418 * thing to do, but at least if we are running
419 * a routing process they will come back.
420 */
421 in_ifadown(&ia->ia_ifa, 1);
422 /*
423 * XXX horrible hack to detect that we are being called
424 * from if_detach()
425 */
426 if (ifaddr_byindex(ifp->if_index) == NULL) {
427 in_pcbpurgeif0(&ripcbinfo, ifp);
428 in_pcbpurgeif0(&udbinfo, ifp);
429 }
430 error = 0;
431 break;
432
433 default:
434 if (ifp == 0 || ifp->if_ioctl == 0)
435 return (EOPNOTSUPP);
436 return ((*ifp->if_ioctl)(ifp, cmd, data));
437 }
438
439 /*
440 * Protect from ipintr() traversing address list while we're modifying
441 * it.
442 */
443 s = splnet();
444 TAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifa_link);
445 TAILQ_REMOVE(&in_ifaddrhead, ia, ia_link);
446 LIST_REMOVE(ia, ia_hash);
447 IFAFREE(&ia->ia_ifa);
448 splx(s);
449
450 return (error);
451 }
452
453 /*
454 * SIOC[GAD]LIFADDR.
455 * SIOCGLIFADDR: get first address. (?!?)
456 * SIOCGLIFADDR with IFLR_PREFIX:
457 * get first address that matches the specified prefix.
458 * SIOCALIFADDR: add the specified address.
459 * SIOCALIFADDR with IFLR_PREFIX:
460 * EINVAL since we can't deduce hostid part of the address.
461 * SIOCDLIFADDR: delete the specified address.
462 * SIOCDLIFADDR with IFLR_PREFIX:
463 * delete the first address that matches the specified prefix.
464 * return values:
465 * EINVAL on invalid parameters
466 * EADDRNOTAVAIL on prefix match failed/specified address not found
467 * other values may be returned from in_ioctl()
468 */
469 static int
470 in_lifaddr_ioctl(so, cmd, data, ifp, td)
471 struct socket *so;
472 u_long cmd;
473 caddr_t data;
474 struct ifnet *ifp;
475 struct thread *td;
476 {
477 struct if_laddrreq *iflr = (struct if_laddrreq *)data;
478 struct ifaddr *ifa;
479
480 /* sanity checks */
481 if (!data || !ifp) {
482 panic("invalid argument to in_lifaddr_ioctl");
483 /*NOTRECHED*/
484 }
485
486 switch (cmd) {
487 case SIOCGLIFADDR:
488 /* address must be specified on GET with IFLR_PREFIX */
489 if ((iflr->flags & IFLR_PREFIX) == 0)
490 break;
491 /*FALLTHROUGH*/
492 case SIOCALIFADDR:
493 case SIOCDLIFADDR:
494 /* address must be specified on ADD and DELETE */
495 if (iflr->addr.ss_family != AF_INET)
496 return EINVAL;
497 if (iflr->addr.ss_len != sizeof(struct sockaddr_in))
498 return EINVAL;
499 /* XXX need improvement */
500 if (iflr->dstaddr.ss_family
501 && iflr->dstaddr.ss_family != AF_INET)
502 return EINVAL;
503 if (iflr->dstaddr.ss_family
504 && iflr->dstaddr.ss_len != sizeof(struct sockaddr_in))
505 return EINVAL;
506 break;
507 default: /*shouldn't happen*/
508 return EOPNOTSUPP;
509 }
510 if (sizeof(struct in_addr) * 8 < iflr->prefixlen)
511 return EINVAL;
512
513 switch (cmd) {
514 case SIOCALIFADDR:
515 {
516 struct in_aliasreq ifra;
517
518 if (iflr->flags & IFLR_PREFIX)
519 return EINVAL;
520
521 /* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
522 bzero(&ifra, sizeof(ifra));
523 bcopy(iflr->iflr_name, ifra.ifra_name,
524 sizeof(ifra.ifra_name));
525
526 bcopy(&iflr->addr, &ifra.ifra_addr, iflr->addr.ss_len);
527
528 if (iflr->dstaddr.ss_family) { /*XXX*/
529 bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
530 iflr->dstaddr.ss_len);
531 }
532
533 ifra.ifra_mask.sin_family = AF_INET;
534 ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
535 in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);
536
537 return in_control(so, SIOCAIFADDR, (caddr_t)&ifra, ifp, td);
538 }
539 case SIOCGLIFADDR:
540 case SIOCDLIFADDR:
541 {
542 struct in_ifaddr *ia;
543 struct in_addr mask, candidate, match;
544 struct sockaddr_in *sin;
545 int cmp;
546
547 bzero(&mask, sizeof(mask));
548 if (iflr->flags & IFLR_PREFIX) {
549 /* lookup a prefix rather than address. */
550 in_len2mask(&mask, iflr->prefixlen);
551
552 sin = (struct sockaddr_in *)&iflr->addr;
553 match.s_addr = sin->sin_addr.s_addr;
554 match.s_addr &= mask.s_addr;
555
556 /* if you set extra bits, that's wrong */
557 if (match.s_addr != sin->sin_addr.s_addr)
558 return EINVAL;
559
560 cmp = 1;
561 } else {
562 if (cmd == SIOCGLIFADDR) {
563 /* on getting an address, take the 1st match */
564 cmp = 0; /*XXX*/
565 } else {
566 /* on deleting an address, do exact match */
567 in_len2mask(&mask, 32);
568 sin = (struct sockaddr_in *)&iflr->addr;
569 match.s_addr = sin->sin_addr.s_addr;
570
571 cmp = 1;
572 }
573 }
574
575 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
576 if (ifa->ifa_addr->sa_family != AF_INET6)
577 continue;
578 if (!cmp)
579 break;
580 candidate.s_addr = ((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr;
581 candidate.s_addr &= mask.s_addr;
582 if (candidate.s_addr == match.s_addr)
583 break;
584 }
585 if (!ifa)
586 return EADDRNOTAVAIL;
587 ia = (struct in_ifaddr *)ifa;
588
589 if (cmd == SIOCGLIFADDR) {
590 /* fill in the if_laddrreq structure */
591 bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len);
592
593 if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
594 bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
595 ia->ia_dstaddr.sin_len);
596 } else
597 bzero(&iflr->dstaddr, sizeof(iflr->dstaddr));
598
599 iflr->prefixlen =
600 in_mask2len(&ia->ia_sockmask.sin_addr);
601
602 iflr->flags = 0; /*XXX*/
603
604 return 0;
605 } else {
606 struct in_aliasreq ifra;
607
608 /* fill in_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
609 bzero(&ifra, sizeof(ifra));
610 bcopy(iflr->iflr_name, ifra.ifra_name,
611 sizeof(ifra.ifra_name));
612
613 bcopy(&ia->ia_addr, &ifra.ifra_addr,
614 ia->ia_addr.sin_len);
615 if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
616 bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
617 ia->ia_dstaddr.sin_len);
618 }
619 bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr,
620 ia->ia_sockmask.sin_len);
621
622 return in_control(so, SIOCDIFADDR, (caddr_t)&ifra,
623 ifp, td);
624 }
625 }
626 }
627
628 return EOPNOTSUPP; /*just for safety*/
629 }
630
631 /*
632 * Delete any existing route for an interface.
633 */
634 void
635 in_ifscrub(ifp, ia)
636 register struct ifnet *ifp;
637 register struct in_ifaddr *ia;
638 {
639
640 if ((ia->ia_flags & IFA_ROUTE) == 0)
641 return;
642 if (ifp->if_flags & (IFF_LOOPBACK|IFF_POINTOPOINT))
643 rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
644 else
645 rtinit(&(ia->ia_ifa), (int)RTM_DELETE, 0);
646 ia->ia_flags &= ~IFA_ROUTE;
647 }
648
649 /*
650 * Initialize an interface's internet address
651 * and routing table entry.
652 */
653 static int
654 in_ifinit(ifp, ia, sin, scrub)
655 register struct ifnet *ifp;
656 register struct in_ifaddr *ia;
657 struct sockaddr_in *sin;
658 int scrub;
659 {
660 register u_long i = ntohl(sin->sin_addr.s_addr);
661 struct sockaddr_in oldaddr;
662 int s = splimp(), flags = RTF_UP, error = 0;
663
664 oldaddr = ia->ia_addr;
665 if (oldaddr.sin_family == AF_INET)
666 LIST_REMOVE(ia, ia_hash);
667 ia->ia_addr = *sin;
668 if (ia->ia_addr.sin_family == AF_INET)
669 LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr),
670 ia, ia_hash);
671 /*
672 * Give the interface a chance to initialize
673 * if this is its first address,
674 * and to validate the address if necessary.
675 */
676 if (ifp->if_ioctl &&
677 (error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia))) {
678 splx(s);
679 /* LIST_REMOVE(ia, ia_hash) is done in in_control */
680 ia->ia_addr = oldaddr;
681 if (ia->ia_addr.sin_family == AF_INET)
682 LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr),
683 ia, ia_hash);
684 return (error);
685 }
686 splx(s);
687 if (scrub) {
688 ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
689 in_ifscrub(ifp, ia);
690 ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
691 }
692 if (IN_CLASSA(i))
693 ia->ia_netmask = IN_CLASSA_NET;
694 else if (IN_CLASSB(i))
695 ia->ia_netmask = IN_CLASSB_NET;
696 else
697 ia->ia_netmask = IN_CLASSC_NET;
698 /*
699 * The subnet mask usually includes at least the standard network part,
700 * but may may be smaller in the case of supernetting.
701 * If it is set, we believe it.
702 */
703 if (ia->ia_subnetmask == 0) {
704 ia->ia_subnetmask = ia->ia_netmask;
705 ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask);
706 } else
707 ia->ia_netmask &= ia->ia_subnetmask;
708 ia->ia_net = i & ia->ia_netmask;
709 ia->ia_subnet = i & ia->ia_subnetmask;
710 in_socktrim(&ia->ia_sockmask);
711 /*
712 * Add route for the network.
713 */
714 ia->ia_ifa.ifa_metric = ifp->if_metric;
715 if (ifp->if_flags & IFF_BROADCAST) {
716 ia->ia_broadaddr.sin_addr.s_addr =
717 htonl(ia->ia_subnet | ~ia->ia_subnetmask);
718 ia->ia_netbroadcast.s_addr =
719 htonl(ia->ia_net | ~ ia->ia_netmask);
720 } else if (ifp->if_flags & IFF_LOOPBACK) {
721 ia->ia_ifa.ifa_dstaddr = ia->ia_ifa.ifa_addr;
722 flags |= RTF_HOST;
723 } else if (ifp->if_flags & IFF_POINTOPOINT) {
724 if (ia->ia_dstaddr.sin_family != AF_INET)
725 return (0);
726 flags |= RTF_HOST;
727 }
728
729 /*-
730 * Don't add host routes for interface addresses of
731 * 0.0.0.0 --> 0.255.255.255 netmask 255.0.0.0. This makes it
732 * possible to assign several such address pairs with consistent
733 * results (no host route) and is required by BOOTP.
734 *
735 * XXX: This is ugly ! There should be a way for the caller to
736 * say that they don't want a host route.
737 */
738 if (ia->ia_addr.sin_addr.s_addr != INADDR_ANY ||
739 ia->ia_netmask != IN_CLASSA_NET ||
740 ia->ia_dstaddr.sin_addr.s_addr != htonl(IN_CLASSA_HOST)) {
741 if ((error = rtinit(&ia->ia_ifa, (int)RTM_ADD, flags)) != 0) {
742 ia->ia_addr = oldaddr;
743 return (error);
744 }
745 ia->ia_flags |= IFA_ROUTE;
746 }
747
748 /*
749 * If the interface supports multicast, join the "all hosts"
750 * multicast group on that interface.
751 */
752 if (ifp->if_flags & IFF_MULTICAST) {
753 struct in_addr addr;
754
755 addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
756 in_addmulti(&addr, ifp);
757 }
758 return (error);
759 }
760
761
762 /*
763 * Return 1 if the address might be a local broadcast address.
764 */
765 int
766 in_broadcast(in, ifp)
767 struct in_addr in;
768 struct ifnet *ifp;
769 {
770 register struct ifaddr *ifa;
771 u_long t;
772
773 if (in.s_addr == INADDR_BROADCAST ||
774 in.s_addr == INADDR_ANY)
775 return 1;
776 if ((ifp->if_flags & IFF_BROADCAST) == 0)
777 return 0;
778 t = ntohl(in.s_addr);
779 /*
780 * Look through the list of addresses for a match
781 * with a broadcast address.
782 */
783 #define ia ((struct in_ifaddr *)ifa)
784 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
785 if (ifa->ifa_addr->sa_family == AF_INET &&
786 (in.s_addr == ia->ia_broadaddr.sin_addr.s_addr ||
787 in.s_addr == ia->ia_netbroadcast.s_addr ||
788 /*
789 * Check for old-style (host 0) broadcast.
790 */
791 t == ia->ia_subnet || t == ia->ia_net) &&
792 /*
793 * Check for an all one subnetmask. These
794 * only exist when an interface gets a secondary
795 * address.
796 */
797 ia->ia_subnetmask != (u_long)0xffffffff)
798 return 1;
799 return (0);
800 #undef ia
801 }
802 /*
803 * Add an address to the list of IP multicast addresses for a given interface.
804 */
805 struct in_multi *
806 in_addmulti(ap, ifp)
807 register struct in_addr *ap;
808 register struct ifnet *ifp;
809 {
810 register struct in_multi *inm;
811 int error;
812 struct sockaddr_in sin;
813 struct ifmultiaddr *ifma;
814 int s = splnet();
815
816 /*
817 * Call generic routine to add membership or increment
818 * refcount. It wants addresses in the form of a sockaddr,
819 * so we build one here (being careful to zero the unused bytes).
820 */
821 bzero(&sin, sizeof sin);
822 sin.sin_family = AF_INET;
823 sin.sin_len = sizeof sin;
824 sin.sin_addr = *ap;
825 error = if_addmulti(ifp, (struct sockaddr *)&sin, &ifma);
826 if (error) {
827 splx(s);
828 return 0;
829 }
830
831 /*
832 * If ifma->ifma_protospec is null, then if_addmulti() created
833 * a new record. Otherwise, we are done.
834 */
835 if (ifma->ifma_protospec != 0) {
836 splx(s);
837 return ifma->ifma_protospec;
838 }
839
840 /* XXX - if_addmulti uses M_WAITOK. Can this really be called
841 at interrupt time? If so, need to fix if_addmulti. XXX */
842 inm = (struct in_multi *)malloc(sizeof(*inm), M_IPMADDR,
843 M_NOWAIT | M_ZERO);
844 if (inm == NULL) {
845 splx(s);
846 return (NULL);
847 }
848
849 inm->inm_addr = *ap;
850 inm->inm_ifp = ifp;
851 inm->inm_ifma = ifma;
852 ifma->ifma_protospec = inm;
853 LIST_INSERT_HEAD(&in_multihead, inm, inm_link);
854
855 /*
856 * Let IGMP know that we have joined a new IP multicast group.
857 */
858 igmp_joingroup(inm);
859 splx(s);
860 return (inm);
861 }
862
863 /*
864 * Delete a multicast address record.
865 */
866 void
867 in_delmulti(inm)
868 register struct in_multi *inm;
869 {
870 struct ifmultiaddr *ifma = inm->inm_ifma;
871 struct in_multi my_inm;
872 int s = splnet();
873
874 my_inm.inm_ifp = NULL ; /* don't send the leave msg */
875 if (ifma->ifma_refcount == 1) {
876 /*
877 * No remaining claims to this record; let IGMP know that
878 * we are leaving the multicast group.
879 * But do it after the if_delmulti() which might reset
880 * the interface and nuke the packet.
881 */
882 my_inm = *inm ;
883 ifma->ifma_protospec = 0;
884 LIST_REMOVE(inm, inm_link);
885 free(inm, M_IPMADDR);
886 }
887 /* XXX - should be separate API for when we have an ifma? */
888 if_delmulti(ifma->ifma_ifp, ifma->ifma_addr);
889 if (my_inm.inm_ifp != NULL)
890 igmp_leavegroup(&my_inm);
891 splx(s);
892 }
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