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: stable/9/sys/netinet/in.c 271842 2014-09-18 22:12:52Z asomers $");
35
36 #include "opt_mpath.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/jail.h>
45 #include <sys/kernel.h>
46 #include <sys/proc.h>
47 #include <sys/sysctl.h>
48 #include <sys/syslog.h>
49
50 #include <net/if.h>
51 #include <net/if_var.h>
52 #include <net/if_arp.h>
53 #include <net/if_dl.h>
54 #include <net/if_llatbl.h>
55 #include <net/if_types.h>
56 #include <net/route.h>
57 #include <net/vnet.h>
58
59 #include <netinet/in.h>
60 #include <netinet/in_var.h>
61 #include <netinet/in_pcb.h>
62 #include <netinet/ip_var.h>
63 #include <netinet/igmp_var.h>
64 #include <netinet/udp.h>
65 #include <netinet/udp_var.h>
66
67 static int in_mask2len(struct in_addr *);
68 static void in_len2mask(struct in_addr *, int);
69 static int in_lifaddr_ioctl(struct socket *, u_long, caddr_t,
70 struct ifnet *, struct thread *);
71
72 static int in_addprefix(struct in_ifaddr *, int);
73 static int in_scrubprefix(struct in_ifaddr *, u_int);
74 static void in_socktrim(struct sockaddr_in *);
75 static int in_ifinit(struct ifnet *,
76 struct in_ifaddr *, struct sockaddr_in *, int);
77 static void in_purgemaddrs(struct ifnet *);
78
79 static VNET_DEFINE(int, sameprefixcarponly);
80 #define V_sameprefixcarponly VNET(sameprefixcarponly)
81 SYSCTL_VNET_INT(_net_inet_ip, OID_AUTO, same_prefix_carp_only, CTLFLAG_RW,
82 &VNET_NAME(sameprefixcarponly), 0,
83 "Refuse to create same prefixes on different interfaces");
84
85 VNET_DECLARE(struct inpcbinfo, ripcbinfo);
86 #define V_ripcbinfo VNET(ripcbinfo)
87
88 VNET_DECLARE(struct arpstat, arpstat); /* ARP statistics, see if_arp.h */
89 #define V_arpstat VNET(arpstat)
90
91 /*
92 * Return 1 if an internet address is for a ``local'' host
93 * (one to which we have a connection).
94 */
95 int
in_localaddr(struct in_addr in)96 in_localaddr(struct in_addr in)
97 {
98 register u_long i = ntohl(in.s_addr);
99 register struct in_ifaddr *ia;
100
101 IN_IFADDR_RLOCK();
102 TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
103 if ((i & ia->ia_subnetmask) == ia->ia_subnet) {
104 IN_IFADDR_RUNLOCK();
105 return (1);
106 }
107 }
108 IN_IFADDR_RUNLOCK();
109 return (0);
110 }
111
112 /*
113 * Return 1 if an internet address is for the local host and configured
114 * on one of its interfaces.
115 */
116 int
in_localip(struct in_addr in)117 in_localip(struct in_addr in)
118 {
119 struct in_ifaddr *ia;
120
121 IN_IFADDR_RLOCK();
122 LIST_FOREACH(ia, INADDR_HASH(in.s_addr), ia_hash) {
123 if (IA_SIN(ia)->sin_addr.s_addr == in.s_addr) {
124 IN_IFADDR_RUNLOCK();
125 return (1);
126 }
127 }
128 IN_IFADDR_RUNLOCK();
129 return (0);
130 }
131
132 /*
133 * Determine whether an IP address is in a reserved set of addresses
134 * that may not be forwarded, or whether datagrams to that destination
135 * may be forwarded.
136 */
137 int
in_canforward(struct in_addr in)138 in_canforward(struct in_addr in)
139 {
140 register u_long i = ntohl(in.s_addr);
141 register u_long net;
142
143 if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i) || IN_LINKLOCAL(i))
144 return (0);
145 if (IN_CLASSA(i)) {
146 net = i & IN_CLASSA_NET;
147 if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
148 return (0);
149 }
150 return (1);
151 }
152
153 /*
154 * Trim a mask in a sockaddr
155 */
156 static void
in_socktrim(struct sockaddr_in * ap)157 in_socktrim(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 static int
in_mask2len(mask)171 in_mask2len(mask)
172 struct in_addr *mask;
173 {
174 int x, y;
175 u_char *p;
176
177 p = (u_char *)mask;
178 for (x = 0; x < sizeof(*mask); x++) {
179 if (p[x] != 0xff)
180 break;
181 }
182 y = 0;
183 if (x < sizeof(*mask)) {
184 for (y = 0; y < 8; y++) {
185 if ((p[x] & (0x80 >> y)) == 0)
186 break;
187 }
188 }
189 return (x * 8 + y);
190 }
191
192 static void
in_len2mask(struct in_addr * mask,int len)193 in_len2mask(struct in_addr *mask, int len)
194 {
195 int i;
196 u_char *p;
197
198 p = (u_char *)mask;
199 bzero(mask, sizeof(*mask));
200 for (i = 0; i < len / 8; i++)
201 p[i] = 0xff;
202 if (len % 8)
203 p[i] = (0xff00 >> (len % 8)) & 0xff;
204 }
205
206 /*
207 * Generic internet control operations (ioctl's).
208 *
209 * ifp is NULL if not an interface-specific ioctl.
210 */
211 /* ARGSUSED */
212 int
in_control(struct socket * so,u_long cmd,caddr_t data,struct ifnet * ifp,struct thread * td)213 in_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp,
214 struct thread *td)
215 {
216 register struct ifreq *ifr = (struct ifreq *)data;
217 register struct in_ifaddr *ia, *iap;
218 register struct ifaddr *ifa;
219 struct in_addr allhosts_addr;
220 struct in_addr dst;
221 struct in_ifinfo *ii;
222 struct in_aliasreq *ifra = (struct in_aliasreq *)data;
223 struct sockaddr_in oldaddr;
224 int error, hostIsNew, iaIsNew, maskIsNew;
225 int iaIsFirst;
226
227 ia = NULL;
228 iaIsFirst = 0;
229 iaIsNew = 0;
230 allhosts_addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
231
232 /*
233 * Filter out ioctls we implement directly; forward the rest on to
234 * in_lifaddr_ioctl() and ifp->if_ioctl().
235 */
236 switch (cmd) {
237 case SIOCAIFADDR:
238 case SIOCDIFADDR:
239 case SIOCGIFADDR:
240 case SIOCGIFBRDADDR:
241 case SIOCGIFDSTADDR:
242 case SIOCGIFNETMASK:
243 case SIOCSIFADDR:
244 case SIOCSIFBRDADDR:
245 case SIOCSIFDSTADDR:
246 case SIOCSIFNETMASK:
247 break;
248
249 case SIOCALIFADDR:
250 if (td != NULL) {
251 error = priv_check(td, PRIV_NET_ADDIFADDR);
252 if (error)
253 return (error);
254 }
255 if (ifp == NULL)
256 return (EINVAL);
257 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
258
259 case SIOCDLIFADDR:
260 if (td != NULL) {
261 error = priv_check(td, PRIV_NET_DELIFADDR);
262 if (error)
263 return (error);
264 }
265 if (ifp == NULL)
266 return (EINVAL);
267 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
268
269 case SIOCGLIFADDR:
270 if (ifp == NULL)
271 return (EINVAL);
272 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
273
274 default:
275 if (ifp == NULL || ifp->if_ioctl == NULL)
276 return (EOPNOTSUPP);
277 return ((*ifp->if_ioctl)(ifp, cmd, data));
278 }
279
280 if (ifp == NULL)
281 return (EADDRNOTAVAIL);
282
283 /*
284 * Security checks before we get involved in any work.
285 */
286 switch (cmd) {
287 case SIOCAIFADDR:
288 case SIOCSIFADDR:
289 case SIOCSIFBRDADDR:
290 case SIOCSIFNETMASK:
291 case SIOCSIFDSTADDR:
292 if (td != NULL) {
293 error = priv_check(td, PRIV_NET_ADDIFADDR);
294 if (error)
295 return (error);
296 }
297 break;
298
299 case SIOCDIFADDR:
300 if (td != NULL) {
301 error = priv_check(td, PRIV_NET_DELIFADDR);
302 if (error)
303 return (error);
304 }
305 break;
306 }
307
308 /*
309 * Find address for this interface, if it exists.
310 *
311 * If an alias address was specified, find that one instead of the
312 * first one on the interface, if possible.
313 */
314 dst = ((struct sockaddr_in *)&ifr->ifr_addr)->sin_addr;
315 IN_IFADDR_RLOCK();
316 LIST_FOREACH(iap, INADDR_HASH(dst.s_addr), ia_hash) {
317 if (iap->ia_ifp == ifp &&
318 iap->ia_addr.sin_addr.s_addr == dst.s_addr) {
319 if (td == NULL || prison_check_ip4(td->td_ucred,
320 &dst) == 0)
321 ia = iap;
322 break;
323 }
324 }
325 if (ia != NULL)
326 ifa_ref(&ia->ia_ifa);
327 IN_IFADDR_RUNLOCK();
328 if (ia == NULL) {
329 IF_ADDR_RLOCK(ifp);
330 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
331 iap = ifatoia(ifa);
332 if (iap->ia_addr.sin_family == AF_INET) {
333 if (td != NULL &&
334 prison_check_ip4(td->td_ucred,
335 &iap->ia_addr.sin_addr) != 0)
336 continue;
337 ia = iap;
338 break;
339 }
340 }
341 if (ia != NULL)
342 ifa_ref(&ia->ia_ifa);
343 IF_ADDR_RUNLOCK(ifp);
344 }
345 if (ia == NULL)
346 iaIsFirst = 1;
347
348 error = 0;
349 switch (cmd) {
350 case SIOCAIFADDR:
351 case SIOCDIFADDR:
352 if (ifra->ifra_addr.sin_family == AF_INET) {
353 struct in_ifaddr *oia;
354
355 IN_IFADDR_RLOCK();
356 for (oia = ia; ia; ia = TAILQ_NEXT(ia, ia_link)) {
357 if (ia->ia_ifp == ifp &&
358 ia->ia_addr.sin_addr.s_addr ==
359 ifra->ifra_addr.sin_addr.s_addr)
360 break;
361 }
362 if (ia != NULL && ia != oia)
363 ifa_ref(&ia->ia_ifa);
364 if (oia != NULL && ia != oia)
365 ifa_free(&oia->ia_ifa);
366 IN_IFADDR_RUNLOCK();
367 if ((ifp->if_flags & IFF_POINTOPOINT)
368 && (cmd == SIOCAIFADDR)
369 && (ifra->ifra_dstaddr.sin_addr.s_addr
370 == INADDR_ANY)) {
371 error = EDESTADDRREQ;
372 goto out;
373 }
374 }
375 if (cmd == SIOCDIFADDR && ia == NULL) {
376 error = EADDRNOTAVAIL;
377 goto out;
378 }
379 /* FALLTHROUGH */
380 case SIOCSIFADDR:
381 case SIOCSIFNETMASK:
382 case SIOCSIFDSTADDR:
383 if (ia == NULL) {
384 ia = (struct in_ifaddr *)
385 malloc(sizeof *ia, M_IFADDR, M_NOWAIT |
386 M_ZERO);
387 if (ia == NULL) {
388 error = ENOBUFS;
389 goto out;
390 }
391
392 ifa = &ia->ia_ifa;
393 ifa_init(ifa);
394 ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr;
395 ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
396 ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask;
397
398 ia->ia_sockmask.sin_len = 8;
399 ia->ia_sockmask.sin_family = AF_INET;
400 if (ifp->if_flags & IFF_BROADCAST) {
401 ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
402 ia->ia_broadaddr.sin_family = AF_INET;
403 }
404 ia->ia_ifp = ifp;
405
406 ifa_ref(ifa); /* if_addrhead */
407 IF_ADDR_WLOCK(ifp);
408 TAILQ_INSERT_TAIL(&ifp->if_addrhead, ifa, ifa_link);
409 IF_ADDR_WUNLOCK(ifp);
410 ifa_ref(ifa); /* in_ifaddrhead */
411 IN_IFADDR_WLOCK();
412 TAILQ_INSERT_TAIL(&V_in_ifaddrhead, ia, ia_link);
413 IN_IFADDR_WUNLOCK();
414 iaIsNew = 1;
415 }
416 break;
417
418 case SIOCSIFBRDADDR:
419 case SIOCGIFADDR:
420 case SIOCGIFNETMASK:
421 case SIOCGIFDSTADDR:
422 case SIOCGIFBRDADDR:
423 if (ia == NULL) {
424 error = EADDRNOTAVAIL;
425 goto out;
426 }
427 break;
428 }
429
430 /*
431 * Most paths in this switch return directly or via out. Only paths
432 * that remove the address break in order to hit common removal code.
433 */
434 switch (cmd) {
435 case SIOCGIFADDR:
436 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_addr;
437 goto out;
438
439 case SIOCGIFBRDADDR:
440 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
441 error = EINVAL;
442 goto out;
443 }
444 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_broadaddr;
445 goto out;
446
447 case SIOCGIFDSTADDR:
448 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) {
449 error = EINVAL;
450 goto out;
451 }
452 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_dstaddr;
453 goto out;
454
455 case SIOCGIFNETMASK:
456 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_sockmask;
457 goto out;
458
459 case SIOCSIFDSTADDR:
460 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) {
461 error = EINVAL;
462 goto out;
463 }
464 oldaddr = ia->ia_dstaddr;
465 ia->ia_dstaddr = *(struct sockaddr_in *)&ifr->ifr_dstaddr;
466 if (ifp->if_ioctl != NULL) {
467 error = (*ifp->if_ioctl)(ifp, SIOCSIFDSTADDR,
468 (caddr_t)ia);
469 if (error) {
470 ia->ia_dstaddr = oldaddr;
471 goto out;
472 }
473 }
474 if (ia->ia_flags & IFA_ROUTE) {
475 ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr;
476 rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
477 ia->ia_ifa.ifa_dstaddr =
478 (struct sockaddr *)&ia->ia_dstaddr;
479 rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP);
480 }
481 goto out;
482
483 case SIOCSIFBRDADDR:
484 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
485 error = EINVAL;
486 goto out;
487 }
488 ia->ia_broadaddr = *(struct sockaddr_in *)&ifr->ifr_broadaddr;
489 goto out;
490
491 case SIOCSIFADDR:
492 error = in_ifinit(ifp, ia,
493 (struct sockaddr_in *) &ifr->ifr_addr, 1);
494 if (error != 0 && iaIsNew)
495 break;
496 if (error == 0) {
497 ii = ((struct in_ifinfo *)ifp->if_afdata[AF_INET]);
498 if (iaIsFirst &&
499 (ifp->if_flags & IFF_MULTICAST) != 0) {
500 error = in_joingroup(ifp, &allhosts_addr,
501 NULL, &ii->ii_allhosts);
502 }
503 EVENTHANDLER_INVOKE(ifaddr_event, ifp);
504 }
505 error = 0;
506 goto out;
507
508 case SIOCSIFNETMASK:
509 ia->ia_sockmask.sin_addr = ifra->ifra_addr.sin_addr;
510 ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr);
511 goto out;
512
513 case SIOCAIFADDR:
514 maskIsNew = 0;
515 hostIsNew = 1;
516 error = 0;
517 if (ia->ia_addr.sin_family == AF_INET) {
518 if (ifra->ifra_addr.sin_len == 0) {
519 ifra->ifra_addr = ia->ia_addr;
520 hostIsNew = 0;
521 } else if (ifra->ifra_addr.sin_addr.s_addr ==
522 ia->ia_addr.sin_addr.s_addr)
523 hostIsNew = 0;
524 }
525 if (ifra->ifra_mask.sin_len) {
526 /*
527 * QL: XXX
528 * Need to scrub the prefix here in case
529 * the issued command is SIOCAIFADDR with
530 * the same address, but with a different
531 * prefix length. And if the prefix length
532 * is the same as before, then the call is
533 * un-necessarily executed here.
534 */
535 in_ifscrub(ifp, ia, LLE_STATIC);
536 ia->ia_sockmask = ifra->ifra_mask;
537 ia->ia_sockmask.sin_family = AF_INET;
538 ia->ia_subnetmask =
539 ntohl(ia->ia_sockmask.sin_addr.s_addr);
540 maskIsNew = 1;
541 }
542 if ((ifp->if_flags & IFF_POINTOPOINT) &&
543 (ifra->ifra_dstaddr.sin_family == AF_INET)) {
544 in_ifscrub(ifp, ia, LLE_STATIC);
545 ia->ia_dstaddr = ifra->ifra_dstaddr;
546 maskIsNew = 1; /* We lie; but the effect's the same */
547 }
548 if (ifra->ifra_addr.sin_family == AF_INET &&
549 (hostIsNew || maskIsNew))
550 error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
551 if (error != 0 && iaIsNew)
552 break;
553
554 if ((ifp->if_flags & IFF_BROADCAST) &&
555 (ifra->ifra_broadaddr.sin_family == AF_INET))
556 ia->ia_broadaddr = ifra->ifra_broadaddr;
557 if (error == 0) {
558 ii = ((struct in_ifinfo *)ifp->if_afdata[AF_INET]);
559 if (iaIsFirst &&
560 (ifp->if_flags & IFF_MULTICAST) != 0) {
561 error = in_joingroup(ifp, &allhosts_addr,
562 NULL, &ii->ii_allhosts);
563 }
564 EVENTHANDLER_INVOKE(ifaddr_event, ifp);
565 }
566 goto out;
567
568 case SIOCDIFADDR:
569 /*
570 * in_ifscrub kills the interface route.
571 */
572 in_ifscrub(ifp, ia, LLE_STATIC);
573
574 /*
575 * in_ifadown gets rid of all the rest of
576 * the routes. This is not quite the right
577 * thing to do, but at least if we are running
578 * a routing process they will come back.
579 */
580 in_ifadown(&ia->ia_ifa, 1);
581 EVENTHANDLER_INVOKE(ifaddr_event, ifp);
582 error = 0;
583 break;
584
585 default:
586 panic("in_control: unsupported ioctl");
587 }
588
589 IF_ADDR_WLOCK(ifp);
590 /* Re-check that ia is still part of the list. */
591 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
592 if (ifa == &ia->ia_ifa)
593 break;
594 }
595 if (ifa == NULL) {
596 /*
597 * If we lost the race with another thread, there is no need to
598 * try it again for the next loop as there is no other exit
599 * path between here and out.
600 */
601 IF_ADDR_WUNLOCK(ifp);
602 error = EADDRNOTAVAIL;
603 goto out;
604 }
605 TAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifa_link);
606 IF_ADDR_WUNLOCK(ifp);
607 ifa_free(&ia->ia_ifa); /* if_addrhead */
608
609 IN_IFADDR_WLOCK();
610 TAILQ_REMOVE(&V_in_ifaddrhead, ia, ia_link);
611 if (ia->ia_addr.sin_family == AF_INET) {
612 struct in_ifaddr *if_ia;
613
614 LIST_REMOVE(ia, ia_hash);
615 IN_IFADDR_WUNLOCK();
616 /*
617 * If this is the last IPv4 address configured on this
618 * interface, leave the all-hosts group.
619 * No state-change report need be transmitted.
620 */
621 if_ia = NULL;
622 IFP_TO_IA(ifp, if_ia);
623 if (if_ia == NULL) {
624 ii = ((struct in_ifinfo *)ifp->if_afdata[AF_INET]);
625 IN_MULTI_LOCK();
626 if (ii->ii_allhosts) {
627 (void)in_leavegroup_locked(ii->ii_allhosts,
628 NULL);
629 ii->ii_allhosts = NULL;
630 }
631 IN_MULTI_UNLOCK();
632 } else
633 ifa_free(&if_ia->ia_ifa);
634 } else
635 IN_IFADDR_WUNLOCK();
636 ifa_free(&ia->ia_ifa); /* in_ifaddrhead */
637 out:
638 if (ia != NULL)
639 ifa_free(&ia->ia_ifa);
640 return (error);
641 }
642
643 /*
644 * SIOC[GAD]LIFADDR.
645 * SIOCGLIFADDR: get first address. (?!?)
646 * SIOCGLIFADDR with IFLR_PREFIX:
647 * get first address that matches the specified prefix.
648 * SIOCALIFADDR: add the specified address.
649 * SIOCALIFADDR with IFLR_PREFIX:
650 * EINVAL since we can't deduce hostid part of the address.
651 * SIOCDLIFADDR: delete the specified address.
652 * SIOCDLIFADDR with IFLR_PREFIX:
653 * delete the first address that matches the specified prefix.
654 * return values:
655 * EINVAL on invalid parameters
656 * EADDRNOTAVAIL on prefix match failed/specified address not found
657 * other values may be returned from in_ioctl()
658 */
659 static int
in_lifaddr_ioctl(struct socket * so,u_long cmd,caddr_t data,struct ifnet * ifp,struct thread * td)660 in_lifaddr_ioctl(struct socket *so, u_long cmd, caddr_t data,
661 struct ifnet *ifp, struct thread *td)
662 {
663 struct if_laddrreq *iflr = (struct if_laddrreq *)data;
664 struct ifaddr *ifa;
665
666 /* sanity checks */
667 if (data == NULL || ifp == NULL) {
668 panic("invalid argument to in_lifaddr_ioctl");
669 /*NOTRECHED*/
670 }
671
672 switch (cmd) {
673 case SIOCGLIFADDR:
674 /* address must be specified on GET with IFLR_PREFIX */
675 if ((iflr->flags & IFLR_PREFIX) == 0)
676 break;
677 /*FALLTHROUGH*/
678 case SIOCALIFADDR:
679 case SIOCDLIFADDR:
680 /* address must be specified on ADD and DELETE */
681 if (iflr->addr.ss_family != AF_INET)
682 return (EINVAL);
683 if (iflr->addr.ss_len != sizeof(struct sockaddr_in))
684 return (EINVAL);
685 /* XXX need improvement */
686 if (iflr->dstaddr.ss_family
687 && iflr->dstaddr.ss_family != AF_INET)
688 return (EINVAL);
689 if (iflr->dstaddr.ss_family
690 && iflr->dstaddr.ss_len != sizeof(struct sockaddr_in))
691 return (EINVAL);
692 break;
693 default: /*shouldn't happen*/
694 return (EOPNOTSUPP);
695 }
696 if (sizeof(struct in_addr) * 8 < iflr->prefixlen)
697 return (EINVAL);
698
699 switch (cmd) {
700 case SIOCALIFADDR:
701 {
702 struct in_aliasreq ifra;
703
704 if (iflr->flags & IFLR_PREFIX)
705 return (EINVAL);
706
707 /* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR). */
708 bzero(&ifra, sizeof(ifra));
709 bcopy(iflr->iflr_name, ifra.ifra_name,
710 sizeof(ifra.ifra_name));
711
712 bcopy(&iflr->addr, &ifra.ifra_addr, iflr->addr.ss_len);
713
714 if (iflr->dstaddr.ss_family) { /*XXX*/
715 bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
716 iflr->dstaddr.ss_len);
717 }
718
719 ifra.ifra_mask.sin_family = AF_INET;
720 ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
721 in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);
722
723 return (in_control(so, SIOCAIFADDR, (caddr_t)&ifra, ifp, td));
724 }
725 case SIOCGLIFADDR:
726 case SIOCDLIFADDR:
727 {
728 struct in_ifaddr *ia;
729 struct in_addr mask, candidate, match;
730 struct sockaddr_in *sin;
731
732 bzero(&mask, sizeof(mask));
733 bzero(&match, sizeof(match));
734 if (iflr->flags & IFLR_PREFIX) {
735 /* lookup a prefix rather than address. */
736 in_len2mask(&mask, iflr->prefixlen);
737
738 sin = (struct sockaddr_in *)&iflr->addr;
739 match.s_addr = sin->sin_addr.s_addr;
740 match.s_addr &= mask.s_addr;
741
742 /* if you set extra bits, that's wrong */
743 if (match.s_addr != sin->sin_addr.s_addr)
744 return (EINVAL);
745
746 } else {
747 /* on getting an address, take the 1st match */
748 /* on deleting an address, do exact match */
749 if (cmd != SIOCGLIFADDR) {
750 in_len2mask(&mask, 32);
751 sin = (struct sockaddr_in *)&iflr->addr;
752 match.s_addr = sin->sin_addr.s_addr;
753 }
754 }
755
756 IF_ADDR_RLOCK(ifp);
757 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
758 if (ifa->ifa_addr->sa_family != AF_INET)
759 continue;
760 if (match.s_addr == 0)
761 break;
762 candidate.s_addr = ((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr;
763 candidate.s_addr &= mask.s_addr;
764 if (candidate.s_addr == match.s_addr)
765 break;
766 }
767 if (ifa != NULL)
768 ifa_ref(ifa);
769 IF_ADDR_RUNLOCK(ifp);
770 if (ifa == NULL)
771 return (EADDRNOTAVAIL);
772 ia = (struct in_ifaddr *)ifa;
773
774 if (cmd == SIOCGLIFADDR) {
775 /* fill in the if_laddrreq structure */
776 bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len);
777
778 if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
779 bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
780 ia->ia_dstaddr.sin_len);
781 } else
782 bzero(&iflr->dstaddr, sizeof(iflr->dstaddr));
783
784 iflr->prefixlen =
785 in_mask2len(&ia->ia_sockmask.sin_addr);
786
787 iflr->flags = 0; /*XXX*/
788 ifa_free(ifa);
789
790 return (0);
791 } else {
792 struct in_aliasreq ifra;
793
794 /* fill in_aliasreq and do ioctl(SIOCDIFADDR) */
795 bzero(&ifra, sizeof(ifra));
796 bcopy(iflr->iflr_name, ifra.ifra_name,
797 sizeof(ifra.ifra_name));
798
799 bcopy(&ia->ia_addr, &ifra.ifra_addr,
800 ia->ia_addr.sin_len);
801 if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
802 bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
803 ia->ia_dstaddr.sin_len);
804 }
805 bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr,
806 ia->ia_sockmask.sin_len);
807 ifa_free(ifa);
808
809 return (in_control(so, SIOCDIFADDR, (caddr_t)&ifra,
810 ifp, td));
811 }
812 }
813 }
814
815 return (EOPNOTSUPP); /*just for safety*/
816 }
817
818 /*
819 * Delete any existing route for an interface.
820 */
821 void
in_ifscrub(struct ifnet * ifp,struct in_ifaddr * ia,u_int flags)822 in_ifscrub(struct ifnet *ifp, struct in_ifaddr *ia, u_int flags)
823 {
824
825 in_scrubprefix(ia, flags);
826 }
827
828 /*
829 * Initialize an interface's internet address
830 * and routing table entry.
831 */
832 static int
in_ifinit(struct ifnet * ifp,struct in_ifaddr * ia,struct sockaddr_in * sin,int scrub)833 in_ifinit(struct ifnet *ifp, struct in_ifaddr *ia, struct sockaddr_in *sin,
834 int scrub)
835 {
836 register u_long i = ntohl(sin->sin_addr.s_addr);
837 struct sockaddr_in oldaddr;
838 int s = splimp(), flags = RTF_UP, error = 0;
839
840 oldaddr = ia->ia_addr;
841 if (oldaddr.sin_family == AF_INET)
842 LIST_REMOVE(ia, ia_hash);
843 ia->ia_addr = *sin;
844 if (ia->ia_addr.sin_family == AF_INET) {
845 IN_IFADDR_WLOCK();
846 LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr),
847 ia, ia_hash);
848 IN_IFADDR_WUNLOCK();
849 }
850 /*
851 * Give the interface a chance to initialize
852 * if this is its first address,
853 * and to validate the address if necessary.
854 */
855 if (ifp->if_ioctl != NULL) {
856 error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia);
857 if (error) {
858 splx(s);
859 /* LIST_REMOVE(ia, ia_hash) is done in in_control */
860 ia->ia_addr = oldaddr;
861 IN_IFADDR_WLOCK();
862 if (ia->ia_addr.sin_family == AF_INET)
863 LIST_INSERT_HEAD(INADDR_HASH(
864 ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
865 else
866 /*
867 * If oldaddr family is not AF_INET (e.g.
868 * interface has been just created) in_control
869 * does not call LIST_REMOVE, and we end up
870 * with bogus ia entries in hash
871 */
872 LIST_REMOVE(ia, ia_hash);
873 IN_IFADDR_WUNLOCK();
874 return (error);
875 }
876 }
877 splx(s);
878 if (scrub) {
879 ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
880 in_ifscrub(ifp, ia, LLE_STATIC);
881 ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
882 }
883 /*
884 * Be compatible with network classes, if netmask isn't supplied,
885 * guess it based on classes.
886 */
887 if (ia->ia_subnetmask == 0) {
888 if (IN_CLASSA(i))
889 ia->ia_subnetmask = IN_CLASSA_NET;
890 else if (IN_CLASSB(i))
891 ia->ia_subnetmask = IN_CLASSB_NET;
892 else
893 ia->ia_subnetmask = IN_CLASSC_NET;
894 ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask);
895 }
896 ia->ia_subnet = i & ia->ia_subnetmask;
897 in_socktrim(&ia->ia_sockmask);
898 /*
899 * XXX: carp(4) does not have interface route
900 */
901 if (ifp->if_type == IFT_CARP)
902 return (0);
903 /*
904 * Add route for the network.
905 */
906 ia->ia_ifa.ifa_metric = ifp->if_metric;
907 if (ifp->if_flags & IFF_BROADCAST) {
908 if (ia->ia_subnetmask == IN_RFC3021_MASK)
909 ia->ia_broadaddr.sin_addr.s_addr = INADDR_BROADCAST;
910 else
911 ia->ia_broadaddr.sin_addr.s_addr =
912 htonl(ia->ia_subnet | ~ia->ia_subnetmask);
913 } else if (ifp->if_flags & IFF_LOOPBACK) {
914 ia->ia_dstaddr = ia->ia_addr;
915 flags |= RTF_HOST;
916 } else if (ifp->if_flags & IFF_POINTOPOINT) {
917 if (ia->ia_dstaddr.sin_family != AF_INET)
918 return (0);
919 flags |= RTF_HOST;
920 }
921 if ((error = in_addprefix(ia, flags)) != 0)
922 return (error);
923
924 if (ia->ia_addr.sin_addr.s_addr == INADDR_ANY)
925 return (0);
926
927 if (ifp->if_flags & IFF_POINTOPOINT) {
928 if (ia->ia_dstaddr.sin_addr.s_addr == ia->ia_addr.sin_addr.s_addr)
929 return (0);
930 }
931
932
933 /*
934 * add a loopback route to self
935 */
936 if (V_useloopback && !(ifp->if_flags & IFF_LOOPBACK)) {
937 struct route ia_ro;
938
939 bzero(&ia_ro, sizeof(ia_ro));
940 *((struct sockaddr_in *)(&ia_ro.ro_dst)) = ia->ia_addr;
941 rtalloc_ign_fib(&ia_ro, 0, RT_DEFAULT_FIB);
942 if ((ia_ro.ro_rt != NULL) && (ia_ro.ro_rt->rt_ifp != NULL) &&
943 (ia_ro.ro_rt->rt_ifp == V_loif)) {
944 RT_LOCK(ia_ro.ro_rt);
945 RT_ADDREF(ia_ro.ro_rt);
946 RTFREE_LOCKED(ia_ro.ro_rt);
947 } else
948 error = ifa_add_loopback_route((struct ifaddr *)ia,
949 (struct sockaddr *)&ia->ia_addr);
950 if (error == 0)
951 ia->ia_flags |= IFA_RTSELF;
952 if (ia_ro.ro_rt != NULL)
953 RTFREE(ia_ro.ro_rt);
954 }
955
956 return (error);
957 }
958
959 #define rtinitflags(x) \
960 ((((x)->ia_ifp->if_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) != 0) \
961 ? RTF_HOST : 0)
962
963 /*
964 * Check if we have a route for the given prefix already or add one accordingly.
965 */
966 static int
in_addprefix(struct in_ifaddr * target,int flags)967 in_addprefix(struct in_ifaddr *target, int flags)
968 {
969 struct in_ifaddr *ia;
970 struct in_addr prefix, mask, p, m;
971 int error;
972
973 if ((flags & RTF_HOST) != 0) {
974 prefix = target->ia_dstaddr.sin_addr;
975 mask.s_addr = 0;
976 } else {
977 prefix = target->ia_addr.sin_addr;
978 mask = target->ia_sockmask.sin_addr;
979 prefix.s_addr &= mask.s_addr;
980 }
981
982 IN_IFADDR_RLOCK();
983 /* Look for an existing address with the same prefix, mask, and fib */
984 TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
985 if (rtinitflags(ia)) {
986 p = ia->ia_dstaddr.sin_addr;
987
988 if (prefix.s_addr != p.s_addr)
989 continue;
990 } else {
991 p = ia->ia_addr.sin_addr;
992 m = ia->ia_sockmask.sin_addr;
993 p.s_addr &= m.s_addr;
994
995 if (prefix.s_addr != p.s_addr ||
996 mask.s_addr != m.s_addr)
997 continue;
998 }
999 if (target->ia_ifp->if_fib != ia->ia_ifp->if_fib)
1000 continue;
1001
1002 /*
1003 * If we got a matching prefix route inserted by other
1004 * interface address, we are done here.
1005 */
1006 if (ia->ia_flags & IFA_ROUTE) {
1007 #ifdef RADIX_MPATH
1008 if (ia->ia_addr.sin_addr.s_addr ==
1009 target->ia_addr.sin_addr.s_addr) {
1010 IN_IFADDR_RUNLOCK();
1011 return (EEXIST);
1012 } else
1013 break;
1014 #endif
1015 if (V_sameprefixcarponly &&
1016 target->ia_ifp->if_type != IFT_CARP &&
1017 ia->ia_ifp->if_type != IFT_CARP) {
1018 IN_IFADDR_RUNLOCK();
1019 return (EEXIST);
1020 } else {
1021 int fibnum;
1022
1023 fibnum = rt_add_addr_allfibs ? RT_ALL_FIBS :
1024 target->ia_ifp->if_fib;
1025 rt_addrmsg(RTM_ADD, &target->ia_ifa, fibnum);
1026 IN_IFADDR_RUNLOCK();
1027 return (0);
1028 }
1029 }
1030 }
1031 IN_IFADDR_RUNLOCK();
1032
1033 /*
1034 * No-one seem to have this prefix route, so we try to insert it.
1035 */
1036 error = rtinit(&target->ia_ifa, (int)RTM_ADD, flags);
1037 if (!error)
1038 target->ia_flags |= IFA_ROUTE;
1039 return (error);
1040 }
1041
1042 extern void arp_ifscrub(struct ifnet *ifp, uint32_t addr);
1043
1044 /*
1045 * If there is no other address in the system that can serve a route to the
1046 * same prefix, remove the route. Hand over the route to the new address
1047 * otherwise.
1048 */
1049 static int
in_scrubprefix(struct in_ifaddr * target,u_int flags)1050 in_scrubprefix(struct in_ifaddr *target, u_int flags)
1051 {
1052 struct in_ifaddr *ia;
1053 struct in_addr prefix, mask, p;
1054 int error = 0;
1055 struct sockaddr_in prefix0, mask0;
1056
1057 /*
1058 * Remove the loopback route to the interface address.
1059 * The "useloopback" setting is not consulted because if the
1060 * user configures an interface address, turns off this
1061 * setting, and then tries to delete that interface address,
1062 * checking the current setting of "useloopback" would leave
1063 * that interface address loopback route untouched, which
1064 * would be wrong. Therefore the interface address loopback route
1065 * deletion is unconditional.
1066 */
1067 if ((target->ia_addr.sin_addr.s_addr != INADDR_ANY) &&
1068 !(target->ia_ifp->if_flags & IFF_LOOPBACK) &&
1069 (target->ia_flags & IFA_RTSELF)) {
1070 struct route ia_ro;
1071 int freeit = 0;
1072 int fibnum;
1073
1074 bzero(&ia_ro, sizeof(ia_ro));
1075 *((struct sockaddr_in *)(&ia_ro.ro_dst)) = target->ia_addr;
1076 fibnum = target->ia_ifp->if_fib;
1077 rtalloc_ign_fib(&ia_ro, 0, fibnum);
1078 if ((ia_ro.ro_rt != NULL) && (ia_ro.ro_rt->rt_ifp != NULL) &&
1079 (ia_ro.ro_rt->rt_ifp == V_loif)) {
1080 RT_LOCK(ia_ro.ro_rt);
1081 if (ia_ro.ro_rt->rt_refcnt <= 1)
1082 freeit = 1;
1083 else if (flags & LLE_STATIC) {
1084 RT_REMREF(ia_ro.ro_rt);
1085 target->ia_flags &= ~IFA_RTSELF;
1086 }
1087 RTFREE_LOCKED(ia_ro.ro_rt);
1088 }
1089 if (freeit && (flags & LLE_STATIC)) {
1090 error = ifa_del_loopback_route((struct ifaddr *)target,
1091 (struct sockaddr *)&target->ia_addr);
1092 if (error == 0)
1093 target->ia_flags &= ~IFA_RTSELF;
1094 }
1095 if ((flags & LLE_STATIC) &&
1096 !(target->ia_ifp->if_flags & IFF_NOARP))
1097 /* remove arp cache */
1098 arp_ifscrub(target->ia_ifp, IA_SIN(target)->sin_addr.s_addr);
1099 }
1100
1101 if (rtinitflags(target))
1102 prefix = target->ia_dstaddr.sin_addr;
1103 else {
1104 prefix = target->ia_addr.sin_addr;
1105 mask = target->ia_sockmask.sin_addr;
1106 prefix.s_addr &= mask.s_addr;
1107 }
1108
1109 if ((target->ia_flags & IFA_ROUTE) == 0) {
1110 int fibnum;
1111
1112 fibnum = rt_add_addr_allfibs ? RT_ALL_FIBS :
1113 target->ia_ifp->if_fib;
1114 rt_addrmsg(RTM_DELETE, &target->ia_ifa, fibnum);
1115 return (0);
1116 }
1117
1118 IN_IFADDR_RLOCK();
1119 TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
1120 if (rtinitflags(ia))
1121 p = ia->ia_dstaddr.sin_addr;
1122 else {
1123 p = ia->ia_addr.sin_addr;
1124 p.s_addr &= ia->ia_sockmask.sin_addr.s_addr;
1125 }
1126
1127 if ((prefix.s_addr != p.s_addr) ||
1128 !(ia->ia_ifp->if_flags & IFF_UP))
1129 continue;
1130
1131 /*
1132 * If we got a matching prefix address, move IFA_ROUTE and
1133 * the route itself to it. Make sure that routing daemons
1134 * get a heads-up.
1135 *
1136 * XXX: a special case for carp(4) interface - this should
1137 * be more generally specified as an interface that
1138 * doesn't support such action.
1139 */
1140 if ((ia->ia_flags & IFA_ROUTE) == 0
1141 && (ia->ia_ifp->if_type != IFT_CARP)) {
1142 ifa_ref(&ia->ia_ifa);
1143 IN_IFADDR_RUNLOCK();
1144 error = rtinit(&(target->ia_ifa), (int)RTM_DELETE,
1145 rtinitflags(target));
1146 if (error == 0)
1147 target->ia_flags &= ~IFA_ROUTE;
1148 else
1149 log(LOG_INFO, "in_scrubprefix: err=%d, old prefix delete failed\n",
1150 error);
1151 error = rtinit(&ia->ia_ifa, (int)RTM_ADD,
1152 rtinitflags(ia) | RTF_UP);
1153 if (error == 0)
1154 ia->ia_flags |= IFA_ROUTE;
1155 else
1156 log(LOG_INFO, "in_scrubprefix: err=%d, new prefix add failed\n",
1157 error);
1158 ifa_free(&ia->ia_ifa);
1159 return (error);
1160 }
1161 }
1162 IN_IFADDR_RUNLOCK();
1163
1164 /*
1165 * remove all L2 entries on the given prefix
1166 */
1167 bzero(&prefix0, sizeof(prefix0));
1168 prefix0.sin_len = sizeof(prefix0);
1169 prefix0.sin_family = AF_INET;
1170 prefix0.sin_addr.s_addr = target->ia_subnet;
1171 bzero(&mask0, sizeof(mask0));
1172 mask0.sin_len = sizeof(mask0);
1173 mask0.sin_family = AF_INET;
1174 mask0.sin_addr.s_addr = target->ia_subnetmask;
1175 lltable_prefix_free(AF_INET, (struct sockaddr *)&prefix0,
1176 (struct sockaddr *)&mask0, flags);
1177
1178 /*
1179 * As no-one seem to have this prefix, we can remove the route.
1180 */
1181 error = rtinit(&(target->ia_ifa), (int)RTM_DELETE, rtinitflags(target));
1182 if (error == 0)
1183 target->ia_flags &= ~IFA_ROUTE;
1184 else
1185 log(LOG_INFO, "in_scrubprefix: err=%d, prefix delete failed\n", error);
1186 return (error);
1187 }
1188
1189 #undef rtinitflags
1190
1191 /*
1192 * Return 1 if the address might be a local broadcast address.
1193 */
1194 int
in_broadcast(struct in_addr in,struct ifnet * ifp)1195 in_broadcast(struct in_addr in, struct ifnet *ifp)
1196 {
1197 register struct ifaddr *ifa;
1198 u_long t;
1199
1200 if (in.s_addr == INADDR_BROADCAST ||
1201 in.s_addr == INADDR_ANY)
1202 return (1);
1203 if ((ifp->if_flags & IFF_BROADCAST) == 0)
1204 return (0);
1205 t = ntohl(in.s_addr);
1206 /*
1207 * Look through the list of addresses for a match
1208 * with a broadcast address.
1209 */
1210 #define ia ((struct in_ifaddr *)ifa)
1211 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
1212 if (ifa->ifa_addr->sa_family == AF_INET &&
1213 (in.s_addr == ia->ia_broadaddr.sin_addr.s_addr ||
1214 /*
1215 * Check for old-style (host 0) broadcast, but
1216 * taking into account that RFC 3021 obsoletes it.
1217 */
1218 (ia->ia_subnetmask != IN_RFC3021_MASK &&
1219 t == ia->ia_subnet)) &&
1220 /*
1221 * Check for an all one subnetmask. These
1222 * only exist when an interface gets a secondary
1223 * address.
1224 */
1225 ia->ia_subnetmask != (u_long)0xffffffff)
1226 return (1);
1227 return (0);
1228 #undef ia
1229 }
1230
1231 /*
1232 * On interface removal, clean up IPv4 data structures hung off of the ifnet.
1233 */
1234 void
in_ifdetach(struct ifnet * ifp)1235 in_ifdetach(struct ifnet *ifp)
1236 {
1237
1238 in_pcbpurgeif0(&V_ripcbinfo, ifp);
1239 in_pcbpurgeif0(&V_udbinfo, ifp);
1240 in_purgemaddrs(ifp);
1241 }
1242
1243 /*
1244 * Delete all IPv4 multicast address records, and associated link-layer
1245 * multicast address records, associated with ifp.
1246 * XXX It looks like domifdetach runs AFTER the link layer cleanup.
1247 * XXX This should not race with ifma_protospec being set during
1248 * a new allocation, if it does, we have bigger problems.
1249 */
1250 static void
in_purgemaddrs(struct ifnet * ifp)1251 in_purgemaddrs(struct ifnet *ifp)
1252 {
1253 LIST_HEAD(,in_multi) purgeinms;
1254 struct in_multi *inm, *tinm;
1255 struct ifmultiaddr *ifma;
1256
1257 LIST_INIT(&purgeinms);
1258 IN_MULTI_LOCK();
1259
1260 /*
1261 * Extract list of in_multi associated with the detaching ifp
1262 * which the PF_INET layer is about to release.
1263 * We need to do this as IF_ADDR_LOCK() may be re-acquired
1264 * by code further down.
1265 */
1266 IF_ADDR_RLOCK(ifp);
1267 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
1268 if (ifma->ifma_addr->sa_family != AF_INET ||
1269 ifma->ifma_protospec == NULL)
1270 continue;
1271 #if 0
1272 KASSERT(ifma->ifma_protospec != NULL,
1273 ("%s: ifma_protospec is NULL", __func__));
1274 #endif
1275 inm = (struct in_multi *)ifma->ifma_protospec;
1276 LIST_INSERT_HEAD(&purgeinms, inm, inm_link);
1277 }
1278 IF_ADDR_RUNLOCK(ifp);
1279
1280 LIST_FOREACH_SAFE(inm, &purgeinms, inm_link, tinm) {
1281 LIST_REMOVE(inm, inm_link);
1282 inm_release_locked(inm);
1283 }
1284 igmp_ifdetach(ifp);
1285
1286 IN_MULTI_UNLOCK();
1287 }
1288
1289 #include <net/if_dl.h>
1290 #include <netinet/if_ether.h>
1291
1292 struct in_llentry {
1293 struct llentry base;
1294 struct sockaddr_in l3_addr4;
1295 };
1296
1297 /*
1298 * Deletes an address from the address table.
1299 * This function is called by the timer functions
1300 * such as arptimer() and nd6_llinfo_timer(), and
1301 * the caller does the locking.
1302 */
1303 static void
in_lltable_free(struct lltable * llt,struct llentry * lle)1304 in_lltable_free(struct lltable *llt, struct llentry *lle)
1305 {
1306 LLE_WUNLOCK(lle);
1307 LLE_LOCK_DESTROY(lle);
1308 free(lle, M_LLTABLE);
1309 }
1310
1311 static struct llentry *
in_lltable_new(const struct sockaddr * l3addr,u_int flags)1312 in_lltable_new(const struct sockaddr *l3addr, u_int flags)
1313 {
1314 struct in_llentry *lle;
1315
1316 lle = malloc(sizeof(struct in_llentry), M_LLTABLE, M_DONTWAIT | M_ZERO);
1317 if (lle == NULL) /* NB: caller generates msg */
1318 return NULL;
1319
1320 /*
1321 * For IPv4 this will trigger "arpresolve" to generate
1322 * an ARP request.
1323 */
1324 lle->base.la_expire = time_uptime; /* mark expired */
1325 lle->l3_addr4 = *(const struct sockaddr_in *)l3addr;
1326 lle->base.lle_refcnt = 1;
1327 lle->base.lle_free = in_lltable_free;
1328 LLE_LOCK_INIT(&lle->base);
1329 callout_init_rw(&lle->base.la_timer, &lle->base.lle_lock,
1330 CALLOUT_RETURNUNLOCKED);
1331
1332 return (&lle->base);
1333 }
1334
1335 #define IN_ARE_MASKED_ADDR_EQUAL(d, a, m) ( \
1336 (((ntohl((d)->sin_addr.s_addr) ^ (a)->sin_addr.s_addr) & (m)->sin_addr.s_addr)) == 0 )
1337
1338 static void
in_lltable_prefix_free(struct lltable * llt,const struct sockaddr * prefix,const struct sockaddr * mask,u_int flags)1339 in_lltable_prefix_free(struct lltable *llt, const struct sockaddr *prefix,
1340 const struct sockaddr *mask, u_int flags)
1341 {
1342 const struct sockaddr_in *pfx = (const struct sockaddr_in *)prefix;
1343 const struct sockaddr_in *msk = (const struct sockaddr_in *)mask;
1344 struct llentry *lle, *next;
1345 int i;
1346 size_t pkts_dropped;
1347
1348 IF_AFDATA_WLOCK(llt->llt_ifp);
1349 for (i = 0; i < LLTBL_HASHTBL_SIZE; i++) {
1350 LIST_FOREACH_SAFE(lle, &llt->lle_head[i], lle_next, next) {
1351 /*
1352 * (flags & LLE_STATIC) means deleting all entries
1353 * including static ARP entries.
1354 */
1355 if (IN_ARE_MASKED_ADDR_EQUAL(satosin(L3_ADDR(lle)),
1356 pfx, msk) && ((flags & LLE_STATIC) ||
1357 !(lle->la_flags & LLE_STATIC))) {
1358 LLE_WLOCK(lle);
1359 if (callout_stop(&lle->la_timer))
1360 LLE_REMREF(lle);
1361 pkts_dropped = llentry_free(lle);
1362 ARPSTAT_ADD(dropped, pkts_dropped);
1363 }
1364 }
1365 }
1366 IF_AFDATA_WUNLOCK(llt->llt_ifp);
1367 }
1368
1369
1370 static int
in_lltable_rtcheck(struct ifnet * ifp,u_int flags,const struct sockaddr * l3addr)1371 in_lltable_rtcheck(struct ifnet *ifp, u_int flags, const struct sockaddr *l3addr)
1372 {
1373 struct rtentry *rt;
1374
1375 KASSERT(l3addr->sa_family == AF_INET,
1376 ("sin_family %d", l3addr->sa_family));
1377
1378 /* XXX rtalloc1_fib should take a const param */
1379 rt = rtalloc1_fib(__DECONST(struct sockaddr *, l3addr), 0, 0,
1380 ifp->if_fib);
1381
1382 if (rt == NULL)
1383 return (EINVAL);
1384
1385 /*
1386 * If the gateway for an existing host route matches the target L3
1387 * address, which is a special route inserted by some implementation
1388 * such as MANET, and the interface is of the correct type, then
1389 * allow for ARP to proceed.
1390 */
1391 if (rt->rt_flags & RTF_GATEWAY) {
1392 if (!(rt->rt_flags & RTF_HOST) || !rt->rt_ifp ||
1393 rt->rt_ifp->if_type != IFT_ETHER ||
1394 (rt->rt_ifp->if_flags & (IFF_NOARP | IFF_STATICARP)) != 0 ||
1395 memcmp(rt->rt_gateway->sa_data, l3addr->sa_data,
1396 sizeof(in_addr_t)) != 0) {
1397 RTFREE_LOCKED(rt);
1398 return (EINVAL);
1399 }
1400 }
1401
1402 /*
1403 * Make sure that at least the destination address is covered
1404 * by the route. This is for handling the case where 2 or more
1405 * interfaces have the same prefix. An incoming packet arrives
1406 * on one interface and the corresponding outgoing packet leaves
1407 * another interface.
1408 */
1409 if (!(rt->rt_flags & RTF_HOST) && rt->rt_ifp != ifp) {
1410 const char *sa, *mask, *addr, *lim;
1411 int len;
1412
1413 mask = (const char *)rt_mask(rt);
1414 /*
1415 * Just being extra cautious to avoid some custom
1416 * code getting into trouble.
1417 */
1418 if (mask == NULL) {
1419 RTFREE_LOCKED(rt);
1420 return (EINVAL);
1421 }
1422
1423 sa = (const char *)rt_key(rt);
1424 addr = (const char *)l3addr;
1425 len = ((const struct sockaddr_in *)l3addr)->sin_len;
1426 lim = addr + len;
1427
1428 for ( ; addr < lim; sa++, mask++, addr++) {
1429 if ((*sa ^ *addr) & *mask) {
1430 #ifdef DIAGNOSTIC
1431 log(LOG_INFO, "IPv4 address: \"%s\" is not on the network\n",
1432 inet_ntoa(((const struct sockaddr_in *)l3addr)->sin_addr));
1433 #endif
1434 RTFREE_LOCKED(rt);
1435 return (EINVAL);
1436 }
1437 }
1438 }
1439
1440 RTFREE_LOCKED(rt);
1441 return (0);
1442 }
1443
1444 /*
1445 * Return NULL if not found or marked for deletion.
1446 * If found return lle read locked.
1447 */
1448 static struct llentry *
in_lltable_lookup(struct lltable * llt,u_int flags,const struct sockaddr * l3addr)1449 in_lltable_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
1450 {
1451 const struct sockaddr_in *sin = (const struct sockaddr_in *)l3addr;
1452 struct ifnet *ifp = llt->llt_ifp;
1453 struct llentry *lle;
1454 struct llentries *lleh;
1455 u_int hashkey;
1456
1457 IF_AFDATA_LOCK_ASSERT(ifp);
1458 KASSERT(l3addr->sa_family == AF_INET,
1459 ("sin_family %d", l3addr->sa_family));
1460
1461 hashkey = sin->sin_addr.s_addr;
1462 lleh = &llt->lle_head[LLATBL_HASH(hashkey, LLTBL_HASHMASK)];
1463 LIST_FOREACH(lle, lleh, lle_next) {
1464 struct sockaddr_in *sa2 = satosin(L3_ADDR(lle));
1465 if (lle->la_flags & LLE_DELETED)
1466 continue;
1467 if (sa2->sin_addr.s_addr == sin->sin_addr.s_addr)
1468 break;
1469 }
1470 if (lle == NULL) {
1471 #ifdef DIAGNOSTIC
1472 if (flags & LLE_DELETE)
1473 log(LOG_INFO, "interface address is missing from cache = %p in delete\n", lle);
1474 #endif
1475 if (!(flags & LLE_CREATE))
1476 return (NULL);
1477 IF_AFDATA_WLOCK_ASSERT(ifp);
1478 /*
1479 * A route that covers the given address must have
1480 * been installed 1st because we are doing a resolution,
1481 * verify this.
1482 */
1483 if (!(flags & LLE_IFADDR) &&
1484 in_lltable_rtcheck(ifp, flags, l3addr) != 0)
1485 goto done;
1486
1487 lle = in_lltable_new(l3addr, flags);
1488 if (lle == NULL) {
1489 log(LOG_INFO, "lla_lookup: new lle malloc failed\n");
1490 goto done;
1491 }
1492 lle->la_flags = flags & ~LLE_CREATE;
1493 if ((flags & (LLE_CREATE | LLE_IFADDR)) == (LLE_CREATE | LLE_IFADDR)) {
1494 bcopy(IF_LLADDR(ifp), &lle->ll_addr, ifp->if_addrlen);
1495 lle->la_flags |= (LLE_VALID | LLE_STATIC);
1496 }
1497
1498 lle->lle_tbl = llt;
1499 lle->lle_head = lleh;
1500 lle->la_flags |= LLE_LINKED;
1501 LIST_INSERT_HEAD(lleh, lle, lle_next);
1502 } else if (flags & LLE_DELETE) {
1503 if (!(lle->la_flags & LLE_IFADDR) || (flags & LLE_IFADDR)) {
1504 LLE_WLOCK(lle);
1505 lle->la_flags |= LLE_DELETED;
1506 EVENTHANDLER_INVOKE(lle_event, lle, LLENTRY_DELETED);
1507 #ifdef DIAGNOSTIC
1508 log(LOG_INFO, "ifaddr cache = %p is deleted\n", lle);
1509 #endif
1510 if ((lle->la_flags &
1511 (LLE_STATIC | LLE_IFADDR)) == LLE_STATIC)
1512 llentry_free(lle);
1513 else
1514 LLE_WUNLOCK(lle);
1515 }
1516 lle = (void *)-1;
1517
1518 }
1519 if (LLE_IS_VALID(lle)) {
1520 if (flags & LLE_EXCLUSIVE)
1521 LLE_WLOCK(lle);
1522 else
1523 LLE_RLOCK(lle);
1524 }
1525 done:
1526 return (lle);
1527 }
1528
1529 static int
in_lltable_dump(struct lltable * llt,struct sysctl_req * wr)1530 in_lltable_dump(struct lltable *llt, struct sysctl_req *wr)
1531 {
1532 #define SIN(lle) ((struct sockaddr_in *) L3_ADDR(lle))
1533 struct ifnet *ifp = llt->llt_ifp;
1534 struct llentry *lle;
1535 /* XXX stack use */
1536 struct {
1537 struct rt_msghdr rtm;
1538 struct sockaddr_inarp sin;
1539 struct sockaddr_dl sdl;
1540 } arpc;
1541 int error, i;
1542
1543 LLTABLE_LOCK_ASSERT();
1544
1545 error = 0;
1546 for (i = 0; i < LLTBL_HASHTBL_SIZE; i++) {
1547 LIST_FOREACH(lle, &llt->lle_head[i], lle_next) {
1548 struct sockaddr_dl *sdl;
1549
1550 /* skip deleted entries */
1551 if ((lle->la_flags & LLE_DELETED) == LLE_DELETED)
1552 continue;
1553 /* Skip if jailed and not a valid IP of the prison. */
1554 if (prison_if(wr->td->td_ucred, L3_ADDR(lle)) != 0)
1555 continue;
1556 /*
1557 * produce a msg made of:
1558 * struct rt_msghdr;
1559 * struct sockaddr_inarp; (IPv4)
1560 * struct sockaddr_dl;
1561 */
1562 bzero(&arpc, sizeof(arpc));
1563 arpc.rtm.rtm_msglen = sizeof(arpc);
1564 arpc.rtm.rtm_version = RTM_VERSION;
1565 arpc.rtm.rtm_type = RTM_GET;
1566 arpc.rtm.rtm_flags = RTF_UP;
1567 arpc.rtm.rtm_addrs = RTA_DST | RTA_GATEWAY;
1568 arpc.sin.sin_family = AF_INET;
1569 arpc.sin.sin_len = sizeof(arpc.sin);
1570 arpc.sin.sin_addr.s_addr = SIN(lle)->sin_addr.s_addr;
1571
1572 /* publish */
1573 if (lle->la_flags & LLE_PUB) {
1574 arpc.rtm.rtm_flags |= RTF_ANNOUNCE;
1575 /* proxy only */
1576 if (lle->la_flags & LLE_PROXY)
1577 arpc.sin.sin_other = SIN_PROXY;
1578 }
1579
1580 sdl = &arpc.sdl;
1581 sdl->sdl_family = AF_LINK;
1582 sdl->sdl_len = sizeof(*sdl);
1583 sdl->sdl_index = ifp->if_index;
1584 sdl->sdl_type = ifp->if_type;
1585 if ((lle->la_flags & LLE_VALID) == LLE_VALID) {
1586 sdl->sdl_alen = ifp->if_addrlen;
1587 bcopy(&lle->ll_addr, LLADDR(sdl), ifp->if_addrlen);
1588 } else {
1589 sdl->sdl_alen = 0;
1590 bzero(LLADDR(sdl), ifp->if_addrlen);
1591 }
1592
1593 arpc.rtm.rtm_rmx.rmx_expire =
1594 lle->la_flags & LLE_STATIC ? 0 : lle->la_expire;
1595 arpc.rtm.rtm_flags |= (RTF_HOST | RTF_LLDATA);
1596 if (lle->la_flags & LLE_STATIC)
1597 arpc.rtm.rtm_flags |= RTF_STATIC;
1598 arpc.rtm.rtm_index = ifp->if_index;
1599 error = SYSCTL_OUT(wr, &arpc, sizeof(arpc));
1600 if (error)
1601 break;
1602 }
1603 }
1604 return error;
1605 #undef SIN
1606 }
1607
1608 void *
in_domifattach(struct ifnet * ifp)1609 in_domifattach(struct ifnet *ifp)
1610 {
1611 struct in_ifinfo *ii;
1612 struct lltable *llt;
1613
1614 ii = malloc(sizeof(struct in_ifinfo), M_IFADDR, M_WAITOK|M_ZERO);
1615
1616 llt = lltable_init(ifp, AF_INET);
1617 if (llt != NULL) {
1618 llt->llt_prefix_free = in_lltable_prefix_free;
1619 llt->llt_lookup = in_lltable_lookup;
1620 llt->llt_dump = in_lltable_dump;
1621 }
1622 ii->ii_llt = llt;
1623
1624 ii->ii_igmp = igmp_domifattach(ifp);
1625
1626 return ii;
1627 }
1628
1629 void
in_domifdetach(struct ifnet * ifp,void * aux)1630 in_domifdetach(struct ifnet *ifp, void *aux)
1631 {
1632 struct in_ifinfo *ii = (struct in_ifinfo *)aux;
1633
1634 igmp_domifdetach(ifp);
1635 lltable_free(ii->ii_llt);
1636 free(ii, M_IFADDR);
1637 }
1638