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 * $FreeBSD$
35 */
36
37 #include "opt_bootp.h"
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/sockio.h>
41 #include <sys/malloc.h>
42 #include <sys/proc.h>
43 #include <sys/socket.h>
44 #include <sys/kernel.h>
45 #include <sys/sysctl.h>
46
47 #include <net/if.h>
48 #include <net/if_types.h>
49 #include <net/route.h>
50
51 #include <netinet/in.h>
52 #include <netinet/in_var.h>
53 #include <netinet/in_pcb.h>
54
55 #include <netinet/igmp_var.h>
56
57 static MALLOC_DEFINE(M_IPMADDR, "in_multi", "internet multicast address");
58
59 static int in_mask2len __P((struct in_addr *));
60 static void in_len2mask __P((struct in_addr *, int));
61 static int in_lifaddr_ioctl __P((struct socket *, u_long, caddr_t,
62 struct ifnet *, struct proc *));
63
64 static void in_socktrim __P((struct sockaddr_in *));
65 static int in_ifinit __P((struct ifnet *,
66 struct in_ifaddr *, struct sockaddr_in *, int));
67
68 static int subnetsarelocal = 0;
69 SYSCTL_INT(_net_inet_ip, OID_AUTO, subnets_are_local, CTLFLAG_RW,
70 &subnetsarelocal, 0, "");
71
72 struct in_multihead in_multihead; /* XXX BSS initialization */
73
74 extern struct inpcbinfo ripcbinfo;
75 extern struct inpcbinfo udbinfo;
76
77 /*
78 * Return 1 if an internet address is for a ``local'' host
79 * (one to which we have a connection). If subnetsarelocal
80 * is true, this includes other subnets of the local net.
81 * Otherwise, it includes only the directly-connected (sub)nets.
82 */
83 int
84 in_localaddr(in)
85 struct in_addr in;
86 {
87 register u_long i = ntohl(in.s_addr);
88 register struct in_ifaddr *ia;
89
90 if (subnetsarelocal) {
91 TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link)
92 if ((i & ia->ia_netmask) == ia->ia_net)
93 return (1);
94 } else {
95 TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link)
96 if ((i & ia->ia_subnetmask) == ia->ia_subnet)
97 return (1);
98 }
99 return (0);
100 }
101
102 /*
103 * Determine whether an IP address is in a reserved set of addresses
104 * that may not be forwarded, or whether datagrams to that destination
105 * may be forwarded.
106 */
107 int
108 in_canforward(in)
109 struct in_addr in;
110 {
111 register u_long i = ntohl(in.s_addr);
112 register u_long net;
113
114 if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i))
115 return (0);
116 if (IN_CLASSA(i)) {
117 net = i & IN_CLASSA_NET;
118 if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
119 return (0);
120 }
121 return (1);
122 }
123
124 /*
125 * Trim a mask in a sockaddr
126 */
127 static void
128 in_socktrim(ap)
129 struct sockaddr_in *ap;
130 {
131 register char *cplim = (char *) &ap->sin_addr;
132 register char *cp = (char *) (&ap->sin_addr + 1);
133
134 ap->sin_len = 0;
135 while (--cp >= cplim)
136 if (*cp) {
137 (ap)->sin_len = cp - (char *) (ap) + 1;
138 break;
139 }
140 }
141
142 static int
143 in_mask2len(mask)
144 struct in_addr *mask;
145 {
146 int x, y;
147 u_char *p;
148
149 p = (u_char *)mask;
150 for (x = 0; x < sizeof(*mask); x++) {
151 if (p[x] != 0xff)
152 break;
153 }
154 y = 0;
155 if (x < sizeof(*mask)) {
156 for (y = 0; y < 8; y++) {
157 if ((p[x] & (0x80 >> y)) == 0)
158 break;
159 }
160 }
161 return x * 8 + y;
162 }
163
164 static void
165 in_len2mask(mask, len)
166 struct in_addr *mask;
167 int len;
168 {
169 int i;
170 u_char *p;
171
172 p = (u_char *)mask;
173 bzero(mask, sizeof(*mask));
174 for (i = 0; i < len / 8; i++)
175 p[i] = 0xff;
176 if (len % 8)
177 p[i] = (0xff00 >> (len % 8)) & 0xff;
178 }
179
180 static int in_interfaces; /* number of external internet interfaces */
181
182 /*
183 * Generic internet control operations (ioctl's).
184 * Ifp is 0 if not an interface-specific ioctl.
185 */
186 /* ARGSUSED */
187 int
188 in_control(so, cmd, data, ifp, p)
189 struct socket *so;
190 u_long cmd;
191 caddr_t data;
192 register struct ifnet *ifp;
193 struct proc *p;
194 {
195 register struct ifreq *ifr = (struct ifreq *)data;
196 register struct in_ifaddr *ia = 0, *iap;
197 register struct ifaddr *ifa;
198 struct in_addr dst;
199 struct in_ifaddr *oia;
200 struct in_aliasreq *ifra = (struct in_aliasreq *)data;
201 struct sockaddr_in oldaddr;
202 int error, hostIsNew, iaIsNew, maskIsNew, s;
203
204 iaIsNew = 0;
205
206 switch (cmd) {
207 case SIOCALIFADDR:
208 case SIOCDLIFADDR:
209 if (p && (error = suser(p)) != 0)
210 return error;
211 /*fall through*/
212 case SIOCGLIFADDR:
213 if (!ifp)
214 return EINVAL;
215 return in_lifaddr_ioctl(so, cmd, data, ifp, p);
216 }
217
218 /*
219 * Find address for this interface, if it exists.
220 *
221 * If an alias address was specified, find that one instead of
222 * the first one on the interface, if possible
223 */
224 if (ifp) {
225 dst = ((struct sockaddr_in *)&ifr->ifr_addr)->sin_addr;
226 LIST_FOREACH(iap, INADDR_HASH(dst.s_addr), ia_hash)
227 if (iap->ia_ifp == ifp &&
228 iap->ia_addr.sin_addr.s_addr == dst.s_addr) {
229 ia = iap;
230 break;
231 }
232 if (ia == NULL)
233 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
234 iap = ifatoia(ifa);
235 if (iap->ia_addr.sin_family == AF_INET) {
236 ia = iap;
237 break;
238 }
239 }
240 }
241
242 switch (cmd) {
243
244 case SIOCAIFADDR:
245 case SIOCDIFADDR:
246 if (ifp == 0)
247 return (EADDRNOTAVAIL);
248 if (ifra->ifra_addr.sin_family == AF_INET) {
249 for (oia = ia; ia; ia = TAILQ_NEXT(ia, ia_link)) {
250 if (ia->ia_ifp == ifp &&
251 ia->ia_addr.sin_addr.s_addr ==
252 ifra->ifra_addr.sin_addr.s_addr)
253 break;
254 }
255 if ((ifp->if_flags & IFF_POINTOPOINT)
256 && (cmd == SIOCAIFADDR)
257 && (ifra->ifra_dstaddr.sin_addr.s_addr
258 == INADDR_ANY)) {
259 return EDESTADDRREQ;
260 }
261 }
262 if (cmd == SIOCDIFADDR && ia == 0)
263 return (EADDRNOTAVAIL);
264 /* FALLTHROUGH */
265 case SIOCSIFADDR:
266 case SIOCSIFNETMASK:
267 case SIOCSIFDSTADDR:
268 if (p && (error = suser(p)) != 0)
269 return error;
270
271 if (ifp == 0)
272 return (EADDRNOTAVAIL);
273 if (ia == (struct in_ifaddr *)0) {
274 ia = (struct in_ifaddr *)
275 malloc(sizeof *ia, M_IFADDR, M_WAITOK);
276 if (ia == (struct in_ifaddr *)NULL)
277 return (ENOBUFS);
278 bzero((caddr_t)ia, sizeof *ia);
279 /*
280 * Protect from ipintr() traversing address list
281 * while we're modifying it.
282 */
283 s = splnet();
284
285 TAILQ_INSERT_TAIL(&in_ifaddrhead, ia, ia_link);
286 ifa = &ia->ia_ifa;
287 TAILQ_INSERT_TAIL(&ifp->if_addrhead, ifa, ifa_link);
288
289 ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr;
290 ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
291 ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask;
292 ia->ia_sockmask.sin_len = 8;
293 ia->ia_sockmask.sin_family = AF_INET;
294 if (ifp->if_flags & IFF_BROADCAST) {
295 ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
296 ia->ia_broadaddr.sin_family = AF_INET;
297 }
298 ia->ia_ifp = ifp;
299 if (!(ifp->if_flags & IFF_LOOPBACK))
300 in_interfaces++;
301 iaIsNew = 1;
302 splx(s);
303 }
304 break;
305
306 case SIOCSIFBRDADDR:
307 if (p && (error = suser(p)) != 0)
308 return error;
309 /* FALLTHROUGH */
310
311 case SIOCGIFADDR:
312 case SIOCGIFNETMASK:
313 case SIOCGIFDSTADDR:
314 case SIOCGIFBRDADDR:
315 if (ia == (struct in_ifaddr *)0)
316 return (EADDRNOTAVAIL);
317 break;
318 }
319 switch (cmd) {
320
321 case SIOCGIFADDR:
322 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_addr;
323 return (0);
324
325 case SIOCGIFBRDADDR:
326 if ((ifp->if_flags & IFF_BROADCAST) == 0)
327 return (EINVAL);
328 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_broadaddr;
329 return (0);
330
331 case SIOCGIFDSTADDR:
332 if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
333 return (EINVAL);
334 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_dstaddr;
335 return (0);
336
337 case SIOCGIFNETMASK:
338 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_sockmask;
339 return (0);
340
341 case SIOCSIFDSTADDR:
342 if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
343 return (EINVAL);
344 oldaddr = ia->ia_dstaddr;
345 ia->ia_dstaddr = *(struct sockaddr_in *)&ifr->ifr_dstaddr;
346 if (ifp->if_ioctl && (error = (*ifp->if_ioctl)
347 (ifp, SIOCSIFDSTADDR, (caddr_t)ia))) {
348 ia->ia_dstaddr = oldaddr;
349 return (error);
350 }
351 if (ia->ia_flags & IFA_ROUTE) {
352 ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr;
353 rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
354 ia->ia_ifa.ifa_dstaddr =
355 (struct sockaddr *)&ia->ia_dstaddr;
356 rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP);
357 }
358 return (0);
359
360 case SIOCSIFBRDADDR:
361 if ((ifp->if_flags & IFF_BROADCAST) == 0)
362 return (EINVAL);
363 ia->ia_broadaddr = *(struct sockaddr_in *)&ifr->ifr_broadaddr;
364 return (0);
365
366 case SIOCSIFADDR:
367 error = in_ifinit(ifp, ia,
368 (struct sockaddr_in *) &ifr->ifr_addr, 1);
369 if (error != 0 && iaIsNew)
370 break;
371 return (0);
372
373 case SIOCSIFNETMASK:
374 ia->ia_sockmask.sin_addr = ifra->ifra_addr.sin_addr;
375 ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr);
376 return (0);
377
378 case SIOCAIFADDR:
379 maskIsNew = 0;
380 hostIsNew = 1;
381 error = 0;
382 if (ia->ia_addr.sin_family == AF_INET) {
383 if (ifra->ifra_addr.sin_len == 0) {
384 ifra->ifra_addr = ia->ia_addr;
385 hostIsNew = 0;
386 } else if (ifra->ifra_addr.sin_addr.s_addr ==
387 ia->ia_addr.sin_addr.s_addr)
388 hostIsNew = 0;
389 }
390 if (ifra->ifra_mask.sin_len) {
391 in_ifscrub(ifp, ia);
392 ia->ia_sockmask = ifra->ifra_mask;
393 ia->ia_sockmask.sin_family = AF_INET;
394 ia->ia_subnetmask =
395 ntohl(ia->ia_sockmask.sin_addr.s_addr);
396 maskIsNew = 1;
397 }
398 if ((ifp->if_flags & IFF_POINTOPOINT) &&
399 (ifra->ifra_dstaddr.sin_family == AF_INET)) {
400 in_ifscrub(ifp, ia);
401 ia->ia_dstaddr = ifra->ifra_dstaddr;
402 maskIsNew = 1; /* We lie; but the effect's the same */
403 }
404 if (ifra->ifra_addr.sin_family == AF_INET &&
405 (hostIsNew || maskIsNew))
406 error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
407
408 if (error != 0 && iaIsNew)
409 break;
410
411 if ((ifp->if_flags & IFF_BROADCAST) &&
412 (ifra->ifra_broadaddr.sin_family == AF_INET))
413 ia->ia_broadaddr = ifra->ifra_broadaddr;
414 return (error);
415
416 case SIOCDIFADDR:
417 /*
418 * in_ifscrub kills the interface route.
419 */
420 in_ifscrub(ifp, ia);
421 /*
422 * in_ifadown gets rid of all the rest of
423 * the routes. This is not quite the right
424 * thing to do, but at least if we are running
425 * a routing process they will come back.
426 */
427 in_ifadown(&ia->ia_ifa, 1);
428 /*
429 * XXX horrible hack to detect that we are being called
430 * from if_detach()
431 */
432 if (!ifnet_addrs[ifp->if_index - 1]) {
433 in_pcbpurgeif0(LIST_FIRST(ripcbinfo.listhead), ifp);
434 in_pcbpurgeif0(LIST_FIRST(udbinfo.listhead), ifp);
435 }
436 error = 0;
437 break;
438
439 default:
440 if (ifp == 0 || ifp->if_ioctl == 0)
441 return (EOPNOTSUPP);
442 return ((*ifp->if_ioctl)(ifp, cmd, data));
443 }
444
445 /*
446 * Protect from ipintr() traversing address list while we're modifying
447 * it.
448 */
449 s = splnet();
450 TAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifa_link);
451 TAILQ_REMOVE(&in_ifaddrhead, ia, ia_link);
452 LIST_REMOVE(ia, ia_hash);
453 IFAFREE(&ia->ia_ifa);
454 splx(s);
455
456 return (error);
457 }
458
459 /*
460 * SIOC[GAD]LIFADDR.
461 * SIOCGLIFADDR: get first address. (?!?)
462 * SIOCGLIFADDR with IFLR_PREFIX:
463 * get first address that matches the specified prefix.
464 * SIOCALIFADDR: add the specified address.
465 * SIOCALIFADDR with IFLR_PREFIX:
466 * EINVAL since we can't deduce hostid part of the address.
467 * SIOCDLIFADDR: delete the specified address.
468 * SIOCDLIFADDR with IFLR_PREFIX:
469 * delete the first address that matches the specified prefix.
470 * return values:
471 * EINVAL on invalid parameters
472 * EADDRNOTAVAIL on prefix match failed/specified address not found
473 * other values may be returned from in_ioctl()
474 */
475 static int
476 in_lifaddr_ioctl(so, cmd, data, ifp, p)
477 struct socket *so;
478 u_long cmd;
479 caddr_t data;
480 struct ifnet *ifp;
481 struct proc *p;
482 {
483 struct if_laddrreq *iflr = (struct if_laddrreq *)data;
484 struct ifaddr *ifa;
485
486 /* sanity checks */
487 if (!data || !ifp) {
488 panic("invalid argument to in_lifaddr_ioctl");
489 /*NOTRECHED*/
490 }
491
492 switch (cmd) {
493 case SIOCGLIFADDR:
494 /* address must be specified on GET with IFLR_PREFIX */
495 if ((iflr->flags & IFLR_PREFIX) == 0)
496 break;
497 /*FALLTHROUGH*/
498 case SIOCALIFADDR:
499 case SIOCDLIFADDR:
500 /* address must be specified on ADD and DELETE */
501 if (iflr->addr.ss_family != AF_INET)
502 return EINVAL;
503 if (iflr->addr.ss_len != sizeof(struct sockaddr_in))
504 return EINVAL;
505 /* XXX need improvement */
506 if (iflr->dstaddr.ss_family
507 && iflr->dstaddr.ss_family != AF_INET)
508 return EINVAL;
509 if (iflr->dstaddr.ss_family
510 && iflr->dstaddr.ss_len != sizeof(struct sockaddr_in))
511 return EINVAL;
512 break;
513 default: /*shouldn't happen*/
514 return EOPNOTSUPP;
515 }
516 if (sizeof(struct in_addr) * 8 < iflr->prefixlen)
517 return EINVAL;
518
519 switch (cmd) {
520 case SIOCALIFADDR:
521 {
522 struct in_aliasreq ifra;
523
524 if (iflr->flags & IFLR_PREFIX)
525 return EINVAL;
526
527 /* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
528 bzero(&ifra, sizeof(ifra));
529 bcopy(iflr->iflr_name, ifra.ifra_name,
530 sizeof(ifra.ifra_name));
531
532 bcopy(&iflr->addr, &ifra.ifra_addr, iflr->addr.ss_len);
533
534 if (iflr->dstaddr.ss_family) { /*XXX*/
535 bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
536 iflr->dstaddr.ss_len);
537 }
538
539 ifra.ifra_mask.sin_family = AF_INET;
540 ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
541 in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);
542
543 return in_control(so, SIOCAIFADDR, (caddr_t)&ifra, ifp, p);
544 }
545 case SIOCGLIFADDR:
546 case SIOCDLIFADDR:
547 {
548 struct in_ifaddr *ia;
549 struct in_addr mask, candidate, match;
550 struct sockaddr_in *sin;
551 int cmp;
552
553 bzero(&mask, sizeof(mask));
554 if (iflr->flags & IFLR_PREFIX) {
555 /* lookup a prefix rather than address. */
556 in_len2mask(&mask, iflr->prefixlen);
557
558 sin = (struct sockaddr_in *)&iflr->addr;
559 match.s_addr = sin->sin_addr.s_addr;
560 match.s_addr &= mask.s_addr;
561
562 /* if you set extra bits, that's wrong */
563 if (match.s_addr != sin->sin_addr.s_addr)
564 return EINVAL;
565
566 cmp = 1;
567 } else {
568 if (cmd == SIOCGLIFADDR) {
569 /* on getting an address, take the 1st match */
570 cmp = 0; /*XXX*/
571 } else {
572 /* on deleting an address, do exact match */
573 in_len2mask(&mask, 32);
574 sin = (struct sockaddr_in *)&iflr->addr;
575 match.s_addr = sin->sin_addr.s_addr;
576
577 cmp = 1;
578 }
579 }
580
581 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
582 if (ifa->ifa_addr->sa_family != AF_INET6)
583 continue;
584 if (!cmp)
585 break;
586 candidate.s_addr = ((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr;
587 candidate.s_addr &= mask.s_addr;
588 if (candidate.s_addr == match.s_addr)
589 break;
590 }
591 if (!ifa)
592 return EADDRNOTAVAIL;
593 ia = (struct in_ifaddr *)ifa;
594
595 if (cmd == SIOCGLIFADDR) {
596 /* fill in the if_laddrreq structure */
597 bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len);
598
599 if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
600 bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
601 ia->ia_dstaddr.sin_len);
602 } else
603 bzero(&iflr->dstaddr, sizeof(iflr->dstaddr));
604
605 iflr->prefixlen =
606 in_mask2len(&ia->ia_sockmask.sin_addr);
607
608 iflr->flags = 0; /*XXX*/
609
610 return 0;
611 } else {
612 struct in_aliasreq ifra;
613
614 /* fill in_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
615 bzero(&ifra, sizeof(ifra));
616 bcopy(iflr->iflr_name, ifra.ifra_name,
617 sizeof(ifra.ifra_name));
618
619 bcopy(&ia->ia_addr, &ifra.ifra_addr,
620 ia->ia_addr.sin_len);
621 if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
622 bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
623 ia->ia_dstaddr.sin_len);
624 }
625 bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr,
626 ia->ia_sockmask.sin_len);
627
628 return in_control(so, SIOCDIFADDR, (caddr_t)&ifra,
629 ifp, p);
630 }
631 }
632 }
633
634 return EOPNOTSUPP; /*just for safety*/
635 }
636
637 /*
638 * Delete any existing route for an interface.
639 */
640 void
641 in_ifscrub(ifp, ia)
642 register struct ifnet *ifp;
643 register struct in_ifaddr *ia;
644 {
645
646 if ((ia->ia_flags & IFA_ROUTE) == 0)
647 return;
648 if (ifp->if_flags & (IFF_LOOPBACK|IFF_POINTOPOINT))
649 rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
650 else
651 rtinit(&(ia->ia_ifa), (int)RTM_DELETE, 0);
652 ia->ia_flags &= ~IFA_ROUTE;
653 }
654
655 /*
656 * Initialize an interface's internet address
657 * and routing table entry.
658 */
659 static int
660 in_ifinit(ifp, ia, sin, scrub)
661 register struct ifnet *ifp;
662 register struct in_ifaddr *ia;
663 struct sockaddr_in *sin;
664 int scrub;
665 {
666 register u_long i = ntohl(sin->sin_addr.s_addr);
667 struct sockaddr_in oldaddr;
668 int s = splimp(), flags = RTF_UP, error = 0;
669
670 oldaddr = ia->ia_addr;
671 if (oldaddr.sin_family == AF_INET)
672 LIST_REMOVE(ia, ia_hash);
673 ia->ia_addr = *sin;
674 if (ia->ia_addr.sin_family == AF_INET)
675 LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr),
676 ia, ia_hash);
677 /*
678 * Give the interface a chance to initialize
679 * if this is its first address,
680 * and to validate the address if necessary.
681 */
682 if (ifp->if_ioctl &&
683 (error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia))) {
684 splx(s);
685 /* LIST_REMOVE(ia, ia_hash) is done in in_control */
686 ia->ia_addr = oldaddr;
687 if (ia->ia_addr.sin_family == AF_INET)
688 LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr),
689 ia, ia_hash);
690 return (error);
691 }
692 splx(s);
693 if (scrub) {
694 ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
695 in_ifscrub(ifp, ia);
696 ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
697 }
698 if (IN_CLASSA(i))
699 ia->ia_netmask = IN_CLASSA_NET;
700 else if (IN_CLASSB(i))
701 ia->ia_netmask = IN_CLASSB_NET;
702 else
703 ia->ia_netmask = IN_CLASSC_NET;
704 /*
705 * The subnet mask usually includes at least the standard network part,
706 * but may may be smaller in the case of supernetting.
707 * If it is set, we believe it.
708 */
709 if (ia->ia_subnetmask == 0) {
710 ia->ia_subnetmask = ia->ia_netmask;
711 ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask);
712 } else
713 ia->ia_netmask &= ia->ia_subnetmask;
714 ia->ia_net = i & ia->ia_netmask;
715 ia->ia_subnet = i & ia->ia_subnetmask;
716 in_socktrim(&ia->ia_sockmask);
717 /*
718 * Add route for the network.
719 */
720 ia->ia_ifa.ifa_metric = ifp->if_metric;
721 if (ifp->if_flags & IFF_BROADCAST) {
722 ia->ia_broadaddr.sin_addr.s_addr =
723 htonl(ia->ia_subnet | ~ia->ia_subnetmask);
724 ia->ia_netbroadcast.s_addr =
725 htonl(ia->ia_net | ~ ia->ia_netmask);
726 } else if (ifp->if_flags & IFF_LOOPBACK) {
727 ia->ia_ifa.ifa_dstaddr = ia->ia_ifa.ifa_addr;
728 flags |= RTF_HOST;
729 } else if (ifp->if_flags & IFF_POINTOPOINT) {
730 if (ia->ia_dstaddr.sin_family != AF_INET)
731 return (0);
732 flags |= RTF_HOST;
733 }
734
735 /*-
736 * Don't add host routes for interface addresses of
737 * 0.0.0.0 --> 0.255.255.255 netmask 255.0.0.0. This makes it
738 * possible to assign several such address pairs with consistent
739 * results (no host route) and is required by BOOTP.
740 *
741 * XXX: This is ugly ! There should be a way for the caller to
742 * say that they don't want a host route.
743 */
744 if (ia->ia_addr.sin_addr.s_addr != INADDR_ANY ||
745 ia->ia_netmask != IN_CLASSA_NET ||
746 ia->ia_dstaddr.sin_addr.s_addr != htonl(IN_CLASSA_HOST)) {
747 if ((error = rtinit(&ia->ia_ifa, (int)RTM_ADD, flags)) != 0) {
748 ia->ia_addr = oldaddr;
749 return (error);
750 }
751 ia->ia_flags |= IFA_ROUTE;
752 }
753
754 /*
755 * If the interface supports multicast, join the "all hosts"
756 * multicast group on that interface.
757 */
758 if (ifp->if_flags & IFF_MULTICAST) {
759 struct in_addr addr;
760
761 addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
762 in_addmulti(&addr, ifp);
763 }
764 return (error);
765 }
766
767
768 /*
769 * Return 1 if the address might be a local broadcast address.
770 */
771 int
772 in_broadcast(in, ifp)
773 struct in_addr in;
774 struct ifnet *ifp;
775 {
776 register struct ifaddr *ifa;
777 u_long t;
778
779 if (in.s_addr == INADDR_BROADCAST ||
780 in.s_addr == INADDR_ANY)
781 return 1;
782 if ((ifp->if_flags & IFF_BROADCAST) == 0)
783 return 0;
784 t = ntohl(in.s_addr);
785 /*
786 * Look through the list of addresses for a match
787 * with a broadcast address.
788 */
789 #define ia ((struct in_ifaddr *)ifa)
790 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
791 if (ifa->ifa_addr->sa_family == AF_INET &&
792 (in.s_addr == ia->ia_broadaddr.sin_addr.s_addr ||
793 in.s_addr == ia->ia_netbroadcast.s_addr ||
794 /*
795 * Check for old-style (host 0) broadcast.
796 */
797 t == ia->ia_subnet || t == ia->ia_net) &&
798 /*
799 * Check for an all one subnetmask. These
800 * only exist when an interface gets a secondary
801 * address.
802 */
803 ia->ia_subnetmask != (u_long)0xffffffff)
804 return 1;
805 return (0);
806 #undef ia
807 }
808 /*
809 * Add an address to the list of IP multicast addresses for a given interface.
810 */
811 struct in_multi *
812 in_addmulti(ap, ifp)
813 register struct in_addr *ap;
814 register struct ifnet *ifp;
815 {
816 register struct in_multi *inm;
817 int error;
818 struct sockaddr_in sin;
819 struct ifmultiaddr *ifma;
820 int s = splnet();
821
822 /*
823 * Call generic routine to add membership or increment
824 * refcount. It wants addresses in the form of a sockaddr,
825 * so we build one here (being careful to zero the unused bytes).
826 */
827 bzero(&sin, sizeof sin);
828 sin.sin_family = AF_INET;
829 sin.sin_len = sizeof sin;
830 sin.sin_addr = *ap;
831 error = if_addmulti(ifp, (struct sockaddr *)&sin, &ifma);
832 if (error) {
833 splx(s);
834 return 0;
835 }
836
837 /*
838 * If ifma->ifma_protospec is null, then if_addmulti() created
839 * a new record. Otherwise, we are done.
840 */
841 if (ifma->ifma_protospec != 0) {
842 splx(s);
843 return ifma->ifma_protospec;
844 }
845
846 /* XXX - if_addmulti uses M_WAITOK. Can this really be called
847 at interrupt time? If so, need to fix if_addmulti. XXX */
848 inm = (struct in_multi *)malloc(sizeof(*inm), M_IPMADDR, M_NOWAIT);
849 if (inm == NULL) {
850 splx(s);
851 return (NULL);
852 }
853
854 bzero(inm, sizeof *inm);
855 inm->inm_addr = *ap;
856 inm->inm_ifp = ifp;
857 inm->inm_ifma = ifma;
858 ifma->ifma_protospec = inm;
859 LIST_INSERT_HEAD(&in_multihead, inm, inm_link);
860
861 /*
862 * Let IGMP know that we have joined a new IP multicast group.
863 */
864 igmp_joingroup(inm);
865 splx(s);
866 return (inm);
867 }
868
869 /*
870 * Delete a multicast address record.
871 */
872 void
873 in_delmulti(inm)
874 register struct in_multi *inm;
875 {
876 struct ifmultiaddr *ifma = inm->inm_ifma;
877 struct in_multi my_inm;
878 int s = splnet();
879
880 my_inm.inm_ifp = NULL ; /* don't send the leave msg */
881 if (ifma->ifma_refcount == 1) {
882 /*
883 * No remaining claims to this record; let IGMP know that
884 * we are leaving the multicast group.
885 * But do it after the if_delmulti() which might reset
886 * the interface and nuke the packet.
887 */
888 my_inm = *inm ;
889 ifma->ifma_protospec = 0;
890 LIST_REMOVE(inm, inm_link);
891 free(inm, M_IPMADDR);
892 }
893 /* XXX - should be separate API for when we have an ifma? */
894 if_delmulti(ifma->ifma_ifp, ifma->ifma_addr);
895 if (my_inm.inm_ifp != NULL)
896 igmp_leavegroup(&my_inm);
897 splx(s);
898 }
Cache object: 3563aa33ab5f5dd00abab6dc6d6c2bdf
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