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 * Copyright (C) 2001 WIDE Project. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 4. Neither the name of the University nor the names of its contributors
15 * may be used to endorse or promote products derived from this software
16 * without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 * @(#)in.c 8.4 (Berkeley) 1/9/95
31 */
32
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD: src/sys/netinet/in.c,v 1.110 2008/12/02 21:37:28 bz Exp $");
35
36 #include "opt_carp.h"
37
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/sockio.h>
41 #include <sys/malloc.h>
42 #include <sys/priv.h>
43 #include <sys/socket.h>
44 #include <sys/kernel.h>
45 #include <sys/sysctl.h>
46 #include <sys/vimage.h>
47
48 #include <net/if.h>
49 #include <net/if_types.h>
50 #include <net/route.h>
51
52 #include <netinet/in.h>
53 #include <netinet/in_var.h>
54 #include <netinet/in_pcb.h>
55 #include <netinet/ip_var.h>
56 #include <netinet/vinet.h>
57
58 static int in_mask2len(struct in_addr *);
59 static void in_len2mask(struct in_addr *, int);
60 static int in_lifaddr_ioctl(struct socket *, u_long, caddr_t,
61 struct ifnet *, struct thread *);
62
63 static int in_addprefix(struct in_ifaddr *, int);
64 static int in_scrubprefix(struct in_ifaddr *);
65 static void in_socktrim(struct sockaddr_in *);
66 static int in_ifinit(struct ifnet *,
67 struct in_ifaddr *, struct sockaddr_in *, int);
68 static void in_purgemaddrs(struct ifnet *);
69
70 #ifdef VIMAGE_GLOBALS
71 static int subnetsarelocal;
72 static int sameprefixcarponly;
73 extern struct inpcbinfo ripcbinfo;
74 #endif
75
76 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip, OID_AUTO, subnets_are_local,
77 CTLFLAG_RW, subnetsarelocal, 0,
78 "Treat all subnets as directly connected");
79 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip, OID_AUTO, same_prefix_carp_only,
80 CTLFLAG_RW, sameprefixcarponly, 0,
81 "Refuse to create same prefixes on different interfaces");
82
83 /*
84 * Return 1 if an internet address is for a ``local'' host
85 * (one to which we have a connection). If subnetsarelocal
86 * is true, this includes other subnets of the local net.
87 * Otherwise, it includes only the directly-connected (sub)nets.
88 */
89 int
90 in_localaddr(struct in_addr in)
91 {
92 INIT_VNET_INET(curvnet);
93 register u_long i = ntohl(in.s_addr);
94 register struct in_ifaddr *ia;
95
96 if (V_subnetsarelocal) {
97 TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link)
98 if ((i & ia->ia_netmask) == ia->ia_net)
99 return (1);
100 } else {
101 TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link)
102 if ((i & ia->ia_subnetmask) == ia->ia_subnet)
103 return (1);
104 }
105 return (0);
106 }
107
108 /*
109 * Return 1 if an internet address is for the local host and configured
110 * on one of its interfaces.
111 */
112 int
113 in_localip(struct in_addr in)
114 {
115 INIT_VNET_INET(curvnet);
116 struct in_ifaddr *ia;
117
118 LIST_FOREACH(ia, INADDR_HASH(in.s_addr), ia_hash) {
119 if (IA_SIN(ia)->sin_addr.s_addr == in.s_addr)
120 return (1);
121 }
122 return (0);
123 }
124
125 /*
126 * Determine whether an IP address is in a reserved set of addresses
127 * that may not be forwarded, or whether datagrams to that destination
128 * may be forwarded.
129 */
130 int
131 in_canforward(struct in_addr in)
132 {
133 register u_long i = ntohl(in.s_addr);
134 register u_long net;
135
136 if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i) || IN_LINKLOCAL(i))
137 return (0);
138 if (IN_CLASSA(i)) {
139 net = i & IN_CLASSA_NET;
140 if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
141 return (0);
142 }
143 return (1);
144 }
145
146 /*
147 * Trim a mask in a sockaddr
148 */
149 static void
150 in_socktrim(struct sockaddr_in *ap)
151 {
152 register char *cplim = (char *) &ap->sin_addr;
153 register char *cp = (char *) (&ap->sin_addr + 1);
154
155 ap->sin_len = 0;
156 while (--cp >= cplim)
157 if (*cp) {
158 (ap)->sin_len = cp - (char *) (ap) + 1;
159 break;
160 }
161 }
162
163 static int
164 in_mask2len(mask)
165 struct in_addr *mask;
166 {
167 int x, y;
168 u_char *p;
169
170 p = (u_char *)mask;
171 for (x = 0; x < sizeof(*mask); x++) {
172 if (p[x] != 0xff)
173 break;
174 }
175 y = 0;
176 if (x < sizeof(*mask)) {
177 for (y = 0; y < 8; y++) {
178 if ((p[x] & (0x80 >> y)) == 0)
179 break;
180 }
181 }
182 return (x * 8 + y);
183 }
184
185 static void
186 in_len2mask(struct in_addr *mask, int len)
187 {
188 int i;
189 u_char *p;
190
191 p = (u_char *)mask;
192 bzero(mask, sizeof(*mask));
193 for (i = 0; i < len / 8; i++)
194 p[i] = 0xff;
195 if (len % 8)
196 p[i] = (0xff00 >> (len % 8)) & 0xff;
197 }
198
199 /*
200 * Generic internet control operations (ioctl's).
201 * Ifp is 0 if not an interface-specific ioctl.
202 */
203 /* ARGSUSED */
204 int
205 in_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp,
206 struct thread *td)
207 {
208 INIT_VNET_INET(curvnet); /* both so and ifp can be NULL here! */
209 register struct ifreq *ifr = (struct ifreq *)data;
210 register struct in_ifaddr *ia, *iap;
211 register struct ifaddr *ifa;
212 struct in_addr allhosts_addr;
213 struct in_addr dst;
214 struct in_ifaddr *oia;
215 struct in_aliasreq *ifra = (struct in_aliasreq *)data;
216 struct sockaddr_in oldaddr;
217 int error, hostIsNew, iaIsNew, maskIsNew, s;
218 int iaIsFirst;
219
220 ia = NULL;
221 iaIsFirst = 0;
222 iaIsNew = 0;
223 allhosts_addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
224
225 switch (cmd) {
226 case SIOCALIFADDR:
227 if (td != NULL) {
228 error = priv_check(td, PRIV_NET_ADDIFADDR);
229 if (error)
230 return (error);
231 }
232 if (ifp == NULL)
233 return (EINVAL);
234 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
235
236 case SIOCDLIFADDR:
237 if (td != NULL) {
238 error = priv_check(td, PRIV_NET_DELIFADDR);
239 if (error)
240 return (error);
241 }
242 if (ifp == NULL)
243 return (EINVAL);
244 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
245
246 case SIOCGLIFADDR:
247 if (ifp == NULL)
248 return (EINVAL);
249 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
250 }
251
252 /*
253 * Find address for this interface, if it exists.
254 *
255 * If an alias address was specified, find that one instead of
256 * the first one on the interface, if possible.
257 */
258 if (ifp != NULL) {
259 dst = ((struct sockaddr_in *)&ifr->ifr_addr)->sin_addr;
260 LIST_FOREACH(iap, INADDR_HASH(dst.s_addr), ia_hash)
261 if (iap->ia_ifp == ifp &&
262 iap->ia_addr.sin_addr.s_addr == dst.s_addr) {
263 ia = iap;
264 break;
265 }
266 if (ia == NULL)
267 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
268 iap = ifatoia(ifa);
269 if (iap->ia_addr.sin_family == AF_INET) {
270 ia = iap;
271 break;
272 }
273 }
274 if (ia == NULL)
275 iaIsFirst = 1;
276 }
277
278 switch (cmd) {
279
280 case SIOCAIFADDR:
281 case SIOCDIFADDR:
282 if (ifp == NULL)
283 return (EADDRNOTAVAIL);
284 if (ifra->ifra_addr.sin_family == AF_INET) {
285 for (oia = ia; ia; ia = TAILQ_NEXT(ia, ia_link)) {
286 if (ia->ia_ifp == ifp &&
287 ia->ia_addr.sin_addr.s_addr ==
288 ifra->ifra_addr.sin_addr.s_addr)
289 break;
290 }
291 if ((ifp->if_flags & IFF_POINTOPOINT)
292 && (cmd == SIOCAIFADDR)
293 && (ifra->ifra_dstaddr.sin_addr.s_addr
294 == INADDR_ANY)) {
295 return (EDESTADDRREQ);
296 }
297 }
298 if (cmd == SIOCDIFADDR && ia == NULL)
299 return (EADDRNOTAVAIL);
300 /* FALLTHROUGH */
301 case SIOCSIFADDR:
302 case SIOCSIFNETMASK:
303 case SIOCSIFDSTADDR:
304 if (td != NULL) {
305 error = priv_check(td, (cmd == SIOCDIFADDR) ?
306 PRIV_NET_DELIFADDR : PRIV_NET_ADDIFADDR);
307 if (error)
308 return (error);
309 }
310
311 if (ifp == NULL)
312 return (EADDRNOTAVAIL);
313 if (ia == NULL) {
314 ia = (struct in_ifaddr *)
315 malloc(sizeof *ia, M_IFADDR, M_WAITOK | M_ZERO);
316 if (ia == NULL)
317 return (ENOBUFS);
318 /*
319 * Protect from ipintr() traversing address list
320 * while we're modifying it.
321 */
322 s = splnet();
323 ifa = &ia->ia_ifa;
324 IFA_LOCK_INIT(ifa);
325 ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr;
326 ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
327 ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask;
328 ifa->ifa_refcnt = 1;
329 TAILQ_INSERT_TAIL(&ifp->if_addrhead, ifa, ifa_link);
330
331 ia->ia_sockmask.sin_len = 8;
332 ia->ia_sockmask.sin_family = AF_INET;
333 if (ifp->if_flags & IFF_BROADCAST) {
334 ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
335 ia->ia_broadaddr.sin_family = AF_INET;
336 }
337 ia->ia_ifp = ifp;
338
339 TAILQ_INSERT_TAIL(&V_in_ifaddrhead, ia, ia_link);
340 splx(s);
341 iaIsNew = 1;
342 }
343 break;
344
345 case SIOCSIFBRDADDR:
346 if (td != NULL) {
347 error = priv_check(td, PRIV_NET_ADDIFADDR);
348 if (error)
349 return (error);
350 }
351 /* FALLTHROUGH */
352
353 case SIOCGIFADDR:
354 case SIOCGIFNETMASK:
355 case SIOCGIFDSTADDR:
356 case SIOCGIFBRDADDR:
357 if (ia == NULL)
358 return (EADDRNOTAVAIL);
359 break;
360 }
361 switch (cmd) {
362
363 case SIOCGIFADDR:
364 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_addr;
365 return (0);
366
367 case SIOCGIFBRDADDR:
368 if ((ifp->if_flags & IFF_BROADCAST) == 0)
369 return (EINVAL);
370 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_broadaddr;
371 return (0);
372
373 case SIOCGIFDSTADDR:
374 if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
375 return (EINVAL);
376 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_dstaddr;
377 return (0);
378
379 case SIOCGIFNETMASK:
380 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_sockmask;
381 return (0);
382
383 case SIOCSIFDSTADDR:
384 if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
385 return (EINVAL);
386 oldaddr = ia->ia_dstaddr;
387 ia->ia_dstaddr = *(struct sockaddr_in *)&ifr->ifr_dstaddr;
388 if (ifp->if_ioctl != NULL) {
389 IFF_LOCKGIANT(ifp);
390 error = (*ifp->if_ioctl)(ifp, SIOCSIFDSTADDR,
391 (caddr_t)ia);
392 IFF_UNLOCKGIANT(ifp);
393 if (error) {
394 ia->ia_dstaddr = oldaddr;
395 return (error);
396 }
397 }
398 if (ia->ia_flags & IFA_ROUTE) {
399 ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr;
400 rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
401 ia->ia_ifa.ifa_dstaddr =
402 (struct sockaddr *)&ia->ia_dstaddr;
403 rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP);
404 }
405 return (0);
406
407 case SIOCSIFBRDADDR:
408 if ((ifp->if_flags & IFF_BROADCAST) == 0)
409 return (EINVAL);
410 ia->ia_broadaddr = *(struct sockaddr_in *)&ifr->ifr_broadaddr;
411 return (0);
412
413 case SIOCSIFADDR:
414 error = in_ifinit(ifp, ia,
415 (struct sockaddr_in *) &ifr->ifr_addr, 1);
416 if (error != 0 && iaIsNew)
417 break;
418 if (error == 0) {
419 if (iaIsFirst && (ifp->if_flags & IFF_MULTICAST) != 0)
420 in_addmulti(&allhosts_addr, ifp);
421 EVENTHANDLER_INVOKE(ifaddr_event, ifp);
422 }
423 return (0);
424
425 case SIOCSIFNETMASK:
426 ia->ia_sockmask.sin_addr = ifra->ifra_addr.sin_addr;
427 ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr);
428 return (0);
429
430 case SIOCAIFADDR:
431 maskIsNew = 0;
432 hostIsNew = 1;
433 error = 0;
434 if (ia->ia_addr.sin_family == AF_INET) {
435 if (ifra->ifra_addr.sin_len == 0) {
436 ifra->ifra_addr = ia->ia_addr;
437 hostIsNew = 0;
438 } else if (ifra->ifra_addr.sin_addr.s_addr ==
439 ia->ia_addr.sin_addr.s_addr)
440 hostIsNew = 0;
441 }
442 if (ifra->ifra_mask.sin_len) {
443 in_ifscrub(ifp, ia);
444 ia->ia_sockmask = ifra->ifra_mask;
445 ia->ia_sockmask.sin_family = AF_INET;
446 ia->ia_subnetmask =
447 ntohl(ia->ia_sockmask.sin_addr.s_addr);
448 maskIsNew = 1;
449 }
450 if ((ifp->if_flags & IFF_POINTOPOINT) &&
451 (ifra->ifra_dstaddr.sin_family == AF_INET)) {
452 in_ifscrub(ifp, ia);
453 ia->ia_dstaddr = ifra->ifra_dstaddr;
454 maskIsNew = 1; /* We lie; but the effect's the same */
455 }
456 if (ifra->ifra_addr.sin_family == AF_INET &&
457 (hostIsNew || maskIsNew))
458 error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
459 if (error != 0 && iaIsNew)
460 break;
461
462 if ((ifp->if_flags & IFF_BROADCAST) &&
463 (ifra->ifra_broadaddr.sin_family == AF_INET))
464 ia->ia_broadaddr = ifra->ifra_broadaddr;
465 if (error == 0) {
466 if (iaIsFirst && (ifp->if_flags & IFF_MULTICAST) != 0)
467 in_addmulti(&allhosts_addr, ifp);
468 EVENTHANDLER_INVOKE(ifaddr_event, ifp);
469 }
470 return (error);
471
472 case SIOCDIFADDR:
473 /*
474 * in_ifscrub kills the interface route.
475 */
476 in_ifscrub(ifp, ia);
477 /*
478 * in_ifadown gets rid of all the rest of
479 * the routes. This is not quite the right
480 * thing to do, but at least if we are running
481 * a routing process they will come back.
482 */
483 in_ifadown(&ia->ia_ifa, 1);
484 EVENTHANDLER_INVOKE(ifaddr_event, ifp);
485 error = 0;
486 break;
487
488 default:
489 if (ifp == NULL || ifp->if_ioctl == NULL)
490 return (EOPNOTSUPP);
491 IFF_LOCKGIANT(ifp);
492 error = (*ifp->if_ioctl)(ifp, cmd, data);
493 IFF_UNLOCKGIANT(ifp);
494 return (error);
495 }
496
497 /*
498 * Protect from ipintr() traversing address list while we're modifying
499 * it.
500 */
501 s = splnet();
502 TAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifa_link);
503 TAILQ_REMOVE(&V_in_ifaddrhead, ia, ia_link);
504 if (ia->ia_addr.sin_family == AF_INET) {
505 LIST_REMOVE(ia, ia_hash);
506 /*
507 * If this is the last IPv4 address configured on this
508 * interface, leave the all-hosts group.
509 * XXX: This is quite ugly because of locking and structure.
510 */
511 oia = NULL;
512 IFP_TO_IA(ifp, oia);
513 if (oia == NULL) {
514 struct in_multi *inm;
515
516 IFF_LOCKGIANT(ifp);
517 IN_MULTI_LOCK();
518 IN_LOOKUP_MULTI(allhosts_addr, ifp, inm);
519 if (inm != NULL)
520 in_delmulti_locked(inm);
521 IN_MULTI_UNLOCK();
522 IFF_UNLOCKGIANT(ifp);
523 }
524 }
525 IFAFREE(&ia->ia_ifa);
526 splx(s);
527
528 return (error);
529 }
530
531 /*
532 * SIOC[GAD]LIFADDR.
533 * SIOCGLIFADDR: get first address. (?!?)
534 * SIOCGLIFADDR with IFLR_PREFIX:
535 * get first address that matches the specified prefix.
536 * SIOCALIFADDR: add the specified address.
537 * SIOCALIFADDR with IFLR_PREFIX:
538 * EINVAL since we can't deduce hostid part of the address.
539 * SIOCDLIFADDR: delete the specified address.
540 * SIOCDLIFADDR with IFLR_PREFIX:
541 * delete the first address that matches the specified prefix.
542 * return values:
543 * EINVAL on invalid parameters
544 * EADDRNOTAVAIL on prefix match failed/specified address not found
545 * other values may be returned from in_ioctl()
546 */
547 static int
548 in_lifaddr_ioctl(struct socket *so, u_long cmd, caddr_t data,
549 struct ifnet *ifp, struct thread *td)
550 {
551 struct if_laddrreq *iflr = (struct if_laddrreq *)data;
552 struct ifaddr *ifa;
553
554 /* sanity checks */
555 if (data == NULL || ifp == NULL) {
556 panic("invalid argument to in_lifaddr_ioctl");
557 /*NOTRECHED*/
558 }
559
560 switch (cmd) {
561 case SIOCGLIFADDR:
562 /* address must be specified on GET with IFLR_PREFIX */
563 if ((iflr->flags & IFLR_PREFIX) == 0)
564 break;
565 /*FALLTHROUGH*/
566 case SIOCALIFADDR:
567 case SIOCDLIFADDR:
568 /* address must be specified on ADD and DELETE */
569 if (iflr->addr.ss_family != AF_INET)
570 return (EINVAL);
571 if (iflr->addr.ss_len != sizeof(struct sockaddr_in))
572 return (EINVAL);
573 /* XXX need improvement */
574 if (iflr->dstaddr.ss_family
575 && iflr->dstaddr.ss_family != AF_INET)
576 return (EINVAL);
577 if (iflr->dstaddr.ss_family
578 && iflr->dstaddr.ss_len != sizeof(struct sockaddr_in))
579 return (EINVAL);
580 break;
581 default: /*shouldn't happen*/
582 return (EOPNOTSUPP);
583 }
584 if (sizeof(struct in_addr) * 8 < iflr->prefixlen)
585 return (EINVAL);
586
587 switch (cmd) {
588 case SIOCALIFADDR:
589 {
590 struct in_aliasreq ifra;
591
592 if (iflr->flags & IFLR_PREFIX)
593 return (EINVAL);
594
595 /* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
596 bzero(&ifra, sizeof(ifra));
597 bcopy(iflr->iflr_name, ifra.ifra_name,
598 sizeof(ifra.ifra_name));
599
600 bcopy(&iflr->addr, &ifra.ifra_addr, iflr->addr.ss_len);
601
602 if (iflr->dstaddr.ss_family) { /*XXX*/
603 bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
604 iflr->dstaddr.ss_len);
605 }
606
607 ifra.ifra_mask.sin_family = AF_INET;
608 ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
609 in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);
610
611 return (in_control(so, SIOCAIFADDR, (caddr_t)&ifra, ifp, td));
612 }
613 case SIOCGLIFADDR:
614 case SIOCDLIFADDR:
615 {
616 struct in_ifaddr *ia;
617 struct in_addr mask, candidate, match;
618 struct sockaddr_in *sin;
619
620 bzero(&mask, sizeof(mask));
621 bzero(&match, sizeof(match));
622 if (iflr->flags & IFLR_PREFIX) {
623 /* lookup a prefix rather than address. */
624 in_len2mask(&mask, iflr->prefixlen);
625
626 sin = (struct sockaddr_in *)&iflr->addr;
627 match.s_addr = sin->sin_addr.s_addr;
628 match.s_addr &= mask.s_addr;
629
630 /* if you set extra bits, that's wrong */
631 if (match.s_addr != sin->sin_addr.s_addr)
632 return (EINVAL);
633
634 } else {
635 /* on getting an address, take the 1st match */
636 /* on deleting an address, do exact match */
637 if (cmd != SIOCGLIFADDR) {
638 in_len2mask(&mask, 32);
639 sin = (struct sockaddr_in *)&iflr->addr;
640 match.s_addr = sin->sin_addr.s_addr;
641 }
642 }
643
644 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
645 if (ifa->ifa_addr->sa_family != AF_INET6)
646 continue;
647 if (match.s_addr == 0)
648 break;
649 candidate.s_addr = ((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr;
650 candidate.s_addr &= mask.s_addr;
651 if (candidate.s_addr == match.s_addr)
652 break;
653 }
654 if (ifa == NULL)
655 return (EADDRNOTAVAIL);
656 ia = (struct in_ifaddr *)ifa;
657
658 if (cmd == SIOCGLIFADDR) {
659 /* fill in the if_laddrreq structure */
660 bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len);
661
662 if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
663 bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
664 ia->ia_dstaddr.sin_len);
665 } else
666 bzero(&iflr->dstaddr, sizeof(iflr->dstaddr));
667
668 iflr->prefixlen =
669 in_mask2len(&ia->ia_sockmask.sin_addr);
670
671 iflr->flags = 0; /*XXX*/
672
673 return (0);
674 } else {
675 struct in_aliasreq ifra;
676
677 /* fill in_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
678 bzero(&ifra, sizeof(ifra));
679 bcopy(iflr->iflr_name, ifra.ifra_name,
680 sizeof(ifra.ifra_name));
681
682 bcopy(&ia->ia_addr, &ifra.ifra_addr,
683 ia->ia_addr.sin_len);
684 if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
685 bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
686 ia->ia_dstaddr.sin_len);
687 }
688 bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr,
689 ia->ia_sockmask.sin_len);
690
691 return (in_control(so, SIOCDIFADDR, (caddr_t)&ifra,
692 ifp, td));
693 }
694 }
695 }
696
697 return (EOPNOTSUPP); /*just for safety*/
698 }
699
700 /*
701 * Delete any existing route for an interface.
702 */
703 void
704 in_ifscrub(struct ifnet *ifp, struct in_ifaddr *ia)
705 {
706
707 in_scrubprefix(ia);
708 }
709
710 /*
711 * Initialize an interface's internet address
712 * and routing table entry.
713 */
714 static int
715 in_ifinit(struct ifnet *ifp, struct in_ifaddr *ia, struct sockaddr_in *sin,
716 int scrub)
717 {
718 INIT_VNET_INET(ifp->if_vnet);
719 register u_long i = ntohl(sin->sin_addr.s_addr);
720 struct sockaddr_in oldaddr;
721 int s = splimp(), flags = RTF_UP, error = 0;
722
723 oldaddr = ia->ia_addr;
724 if (oldaddr.sin_family == AF_INET)
725 LIST_REMOVE(ia, ia_hash);
726 ia->ia_addr = *sin;
727 if (ia->ia_addr.sin_family == AF_INET)
728 LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr),
729 ia, ia_hash);
730 /*
731 * Give the interface a chance to initialize
732 * if this is its first address,
733 * and to validate the address if necessary.
734 */
735 if (ifp->if_ioctl != NULL) {
736 IFF_LOCKGIANT(ifp);
737 error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia);
738 IFF_UNLOCKGIANT(ifp);
739 if (error) {
740 splx(s);
741 /* LIST_REMOVE(ia, ia_hash) is done in in_control */
742 ia->ia_addr = oldaddr;
743 if (ia->ia_addr.sin_family == AF_INET)
744 LIST_INSERT_HEAD(INADDR_HASH(
745 ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
746 else
747 /*
748 * If oldaddr family is not AF_INET (e.g.
749 * interface has been just created) in_control
750 * does not call LIST_REMOVE, and we end up
751 * with bogus ia entries in hash
752 */
753 LIST_REMOVE(ia, ia_hash);
754 return (error);
755 }
756 }
757 splx(s);
758 if (scrub) {
759 ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
760 in_ifscrub(ifp, ia);
761 ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
762 }
763 if (IN_CLASSA(i))
764 ia->ia_netmask = IN_CLASSA_NET;
765 else if (IN_CLASSB(i))
766 ia->ia_netmask = IN_CLASSB_NET;
767 else
768 ia->ia_netmask = IN_CLASSC_NET;
769 /*
770 * The subnet mask usually includes at least the standard network part,
771 * but may may be smaller in the case of supernetting.
772 * If it is set, we believe it.
773 */
774 if (ia->ia_subnetmask == 0) {
775 ia->ia_subnetmask = ia->ia_netmask;
776 ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask);
777 } else
778 ia->ia_netmask &= ia->ia_subnetmask;
779 ia->ia_net = i & ia->ia_netmask;
780 ia->ia_subnet = i & ia->ia_subnetmask;
781 in_socktrim(&ia->ia_sockmask);
782 #ifdef DEV_CARP
783 /*
784 * XXX: carp(4) does not have interface route
785 */
786 if (ifp->if_type == IFT_CARP)
787 return (0);
788 #endif
789 /*
790 * Add route for the network.
791 */
792 ia->ia_ifa.ifa_metric = ifp->if_metric;
793 if (ifp->if_flags & IFF_BROADCAST) {
794 ia->ia_broadaddr.sin_addr.s_addr =
795 htonl(ia->ia_subnet | ~ia->ia_subnetmask);
796 ia->ia_netbroadcast.s_addr =
797 htonl(ia->ia_net | ~ ia->ia_netmask);
798 } else if (ifp->if_flags & IFF_LOOPBACK) {
799 ia->ia_dstaddr = ia->ia_addr;
800 flags |= RTF_HOST;
801 } else if (ifp->if_flags & IFF_POINTOPOINT) {
802 if (ia->ia_dstaddr.sin_family != AF_INET)
803 return (0);
804 flags |= RTF_HOST;
805 }
806 if ((error = in_addprefix(ia, flags)) != 0)
807 return (error);
808
809 return (error);
810 }
811
812 #define rtinitflags(x) \
813 ((((x)->ia_ifp->if_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) != 0) \
814 ? RTF_HOST : 0)
815 /*
816 * Check if we have a route for the given prefix already or add one accordingly.
817 */
818 static int
819 in_addprefix(struct in_ifaddr *target, int flags)
820 {
821 INIT_VNET_INET(curvnet);
822 struct in_ifaddr *ia;
823 struct in_addr prefix, mask, p, m;
824 int error;
825
826 if ((flags & RTF_HOST) != 0) {
827 prefix = target->ia_dstaddr.sin_addr;
828 mask.s_addr = 0;
829 } else {
830 prefix = target->ia_addr.sin_addr;
831 mask = target->ia_sockmask.sin_addr;
832 prefix.s_addr &= mask.s_addr;
833 }
834
835 TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
836 if (rtinitflags(ia)) {
837 p = ia->ia_addr.sin_addr;
838
839 if (prefix.s_addr != p.s_addr)
840 continue;
841 } else {
842 p = ia->ia_addr.sin_addr;
843 m = ia->ia_sockmask.sin_addr;
844 p.s_addr &= m.s_addr;
845
846 if (prefix.s_addr != p.s_addr ||
847 mask.s_addr != m.s_addr)
848 continue;
849 }
850
851 /*
852 * If we got a matching prefix route inserted by other
853 * interface address, we are done here.
854 */
855 if (ia->ia_flags & IFA_ROUTE) {
856 if (V_sameprefixcarponly &&
857 target->ia_ifp->if_type != IFT_CARP &&
858 ia->ia_ifp->if_type != IFT_CARP)
859 return (EEXIST);
860 else
861 return (0);
862 }
863 }
864
865 /*
866 * No-one seem to have this prefix route, so we try to insert it.
867 */
868 error = rtinit(&target->ia_ifa, (int)RTM_ADD, flags);
869 if (!error)
870 target->ia_flags |= IFA_ROUTE;
871 return (error);
872 }
873
874 /*
875 * If there is no other address in the system that can serve a route to the
876 * same prefix, remove the route. Hand over the route to the new address
877 * otherwise.
878 */
879 static int
880 in_scrubprefix(struct in_ifaddr *target)
881 {
882 INIT_VNET_INET(curvnet);
883 struct in_ifaddr *ia;
884 struct in_addr prefix, mask, p;
885 int error;
886
887 if ((target->ia_flags & IFA_ROUTE) == 0)
888 return (0);
889
890 if (rtinitflags(target))
891 prefix = target->ia_dstaddr.sin_addr;
892 else {
893 prefix = target->ia_addr.sin_addr;
894 mask = target->ia_sockmask.sin_addr;
895 prefix.s_addr &= mask.s_addr;
896 }
897
898 TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
899 if (rtinitflags(ia))
900 p = ia->ia_dstaddr.sin_addr;
901 else {
902 p = ia->ia_addr.sin_addr;
903 p.s_addr &= ia->ia_sockmask.sin_addr.s_addr;
904 }
905
906 if (prefix.s_addr != p.s_addr)
907 continue;
908
909 /*
910 * If we got a matching prefix address, move IFA_ROUTE and
911 * the route itself to it. Make sure that routing daemons
912 * get a heads-up.
913 *
914 * XXX: a special case for carp(4) interface
915 */
916 if ((ia->ia_flags & IFA_ROUTE) == 0
917 #ifdef DEV_CARP
918 && (ia->ia_ifp->if_type != IFT_CARP)
919 #endif
920 ) {
921 rtinit(&(target->ia_ifa), (int)RTM_DELETE,
922 rtinitflags(target));
923 target->ia_flags &= ~IFA_ROUTE;
924
925 error = rtinit(&ia->ia_ifa, (int)RTM_ADD,
926 rtinitflags(ia) | RTF_UP);
927 if (error == 0)
928 ia->ia_flags |= IFA_ROUTE;
929 return (error);
930 }
931 }
932
933 /*
934 * As no-one seem to have this prefix, we can remove the route.
935 */
936 rtinit(&(target->ia_ifa), (int)RTM_DELETE, rtinitflags(target));
937 target->ia_flags &= ~IFA_ROUTE;
938 return (0);
939 }
940
941 #undef rtinitflags
942
943 /*
944 * Return 1 if the address might be a local broadcast address.
945 */
946 int
947 in_broadcast(struct in_addr in, struct ifnet *ifp)
948 {
949 register struct ifaddr *ifa;
950 u_long t;
951
952 if (in.s_addr == INADDR_BROADCAST ||
953 in.s_addr == INADDR_ANY)
954 return (1);
955 if ((ifp->if_flags & IFF_BROADCAST) == 0)
956 return (0);
957 t = ntohl(in.s_addr);
958 /*
959 * Look through the list of addresses for a match
960 * with a broadcast address.
961 */
962 #define ia ((struct in_ifaddr *)ifa)
963 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
964 if (ifa->ifa_addr->sa_family == AF_INET &&
965 (in.s_addr == ia->ia_broadaddr.sin_addr.s_addr ||
966 in.s_addr == ia->ia_netbroadcast.s_addr ||
967 /*
968 * Check for old-style (host 0) broadcast.
969 */
970 t == ia->ia_subnet || t == ia->ia_net) &&
971 /*
972 * Check for an all one subnetmask. These
973 * only exist when an interface gets a secondary
974 * address.
975 */
976 ia->ia_subnetmask != (u_long)0xffffffff)
977 return (1);
978 return (0);
979 #undef ia
980 }
981
982 /*
983 * Delete all IPv4 multicast address records, and associated link-layer
984 * multicast address records, associated with ifp.
985 */
986 static void
987 in_purgemaddrs(struct ifnet *ifp)
988 {
989 INIT_VNET_INET(ifp->if_vnet);
990 struct in_multi *inm;
991 struct in_multi *oinm;
992
993 #ifdef DIAGNOSTIC
994 printf("%s: purging ifp %p\n", __func__, ifp);
995 #endif
996 IFF_LOCKGIANT(ifp);
997 IN_MULTI_LOCK();
998 LIST_FOREACH_SAFE(inm, &V_in_multihead, inm_link, oinm) {
999 if (inm->inm_ifp == ifp)
1000 in_delmulti_locked(inm);
1001 }
1002 IN_MULTI_UNLOCK();
1003 IFF_UNLOCKGIANT(ifp);
1004 }
1005
1006 /*
1007 * On interface removal, clean up IPv4 data structures hung off of the ifnet.
1008 */
1009 void
1010 in_ifdetach(struct ifnet *ifp)
1011 {
1012 INIT_VNET_INET(ifp->if_vnet);
1013
1014 in_pcbpurgeif0(&V_ripcbinfo, ifp);
1015 in_pcbpurgeif0(&V_udbinfo, ifp);
1016 in_purgemaddrs(ifp) |