xref: /netbsd-src/sys/netinet/in.c (revision a6f3f22f245acb8ee3bbf6871d7dce989204fa97)
1 /*	$NetBSD: in.c,v 1.161 2015/08/31 16:46:14 ozaki-r Exp $	*/
2 
3 /*
4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the project nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 /*-
33  * Copyright (c) 1998 The NetBSD Foundation, Inc.
34  * All rights reserved.
35  *
36  * This code is derived from software contributed to The NetBSD Foundation
37  * by Public Access Networks Corporation ("Panix").  It was developed under
38  * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon.
39  *
40  * Redistribution and use in source and binary forms, with or without
41  * modification, are permitted provided that the following conditions
42  * are met:
43  * 1. Redistributions of source code must retain the above copyright
44  *    notice, this list of conditions and the following disclaimer.
45  * 2. Redistributions in binary form must reproduce the above copyright
46  *    notice, this list of conditions and the following disclaimer in the
47  *    documentation and/or other materials provided with the distribution.
48  *
49  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
50  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
51  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
52  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
53  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
54  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
55  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
56  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
57  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
58  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
59  * POSSIBILITY OF SUCH DAMAGE.
60  */
61 
62 /*
63  * Copyright (c) 1982, 1986, 1991, 1993
64  *	The Regents of the University of California.  All rights reserved.
65  *
66  * Redistribution and use in source and binary forms, with or without
67  * modification, are permitted provided that the following conditions
68  * are met:
69  * 1. Redistributions of source code must retain the above copyright
70  *    notice, this list of conditions and the following disclaimer.
71  * 2. Redistributions in binary form must reproduce the above copyright
72  *    notice, this list of conditions and the following disclaimer in the
73  *    documentation and/or other materials provided with the distribution.
74  * 3. Neither the name of the University nor the names of its contributors
75  *    may be used to endorse or promote products derived from this software
76  *    without specific prior written permission.
77  *
78  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
79  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
80  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
81  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
82  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
83  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
84  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
85  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
86  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
87  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
88  * SUCH DAMAGE.
89  *
90  *	@(#)in.c	8.4 (Berkeley) 1/9/95
91  */
92 
93 #include <sys/cdefs.h>
94 __KERNEL_RCSID(0, "$NetBSD: in.c,v 1.161 2015/08/31 16:46:14 ozaki-r Exp $");
95 
96 #include "arp.h"
97 #include "ether.h"
98 
99 #ifdef _KERNEL_OPT
100 #include "opt_inet.h"
101 #include "opt_inet_conf.h"
102 #include "opt_mrouting.h"
103 #endif
104 
105 #include <sys/param.h>
106 #include <sys/ioctl.h>
107 #include <sys/errno.h>
108 #include <sys/kernel.h>
109 #include <sys/malloc.h>
110 #include <sys/socket.h>
111 #include <sys/socketvar.h>
112 #include <sys/sysctl.h>
113 #include <sys/systm.h>
114 #include <sys/proc.h>
115 #include <sys/syslog.h>
116 #include <sys/kauth.h>
117 #include <sys/kmem.h>
118 
119 #include <sys/cprng.h>
120 
121 #include <net/if.h>
122 #include <net/route.h>
123 #include <net/pfil.h>
124 
125 #include <net/if_arp.h>
126 #include <net/if_ether.h>
127 #include <net/if_types.h>
128 #include <net/if_llatbl.h>
129 #include <net/if_dl.h>
130 
131 #include <netinet/in_systm.h>
132 #include <netinet/in.h>
133 #include <netinet/in_var.h>
134 #include <netinet/ip.h>
135 #include <netinet/ip_var.h>
136 #include <netinet/in_ifattach.h>
137 #include <netinet/in_pcb.h>
138 #include <netinet/in_selsrc.h>
139 #include <netinet/if_inarp.h>
140 #include <netinet/ip_mroute.h>
141 #include <netinet/igmp_var.h>
142 
143 #ifdef IPSELSRC
144 #include <netinet/in_selsrc.h>
145 #endif
146 
147 static u_int	in_mask2len(struct in_addr *);
148 static void	in_len2mask(struct in_addr *, u_int);
149 static int	in_lifaddr_ioctl(struct socket *, u_long, void *,
150 	struct ifnet *);
151 
152 static int	in_addprefix(struct in_ifaddr *, int);
153 static int	in_scrubprefix(struct in_ifaddr *);
154 static void	in_sysctl_init(struct sysctllog **);
155 
156 #ifndef SUBNETSARELOCAL
157 #define	SUBNETSARELOCAL	1
158 #endif
159 
160 #ifndef HOSTZEROBROADCAST
161 #define HOSTZEROBROADCAST 1
162 #endif
163 
164 /* Note: 61, 127, 251, 509, 1021, 2039 are good. */
165 #ifndef IN_MULTI_HASH_SIZE
166 #define IN_MULTI_HASH_SIZE	509
167 #endif
168 
169 static int			subnetsarelocal = SUBNETSARELOCAL;
170 static int			hostzeroisbroadcast = HOSTZEROBROADCAST;
171 
172 /*
173  * This list is used to keep track of in_multi chains which belong to
174  * deleted interface addresses.  We use in_ifaddr so that a chain head
175  * won't be deallocated until all multicast address record are deleted.
176  */
177 
178 LIST_HEAD(in_multihashhead, in_multi);		/* Type of the hash head */
179 
180 static struct pool		inmulti_pool;
181 static u_int			in_multientries;
182 static struct in_multihashhead *in_multihashtbl;
183 static u_long			in_multihash;
184 static krwlock_t		in_multilock;
185 
186 #define IN_MULTI_HASH(x, ifp) \
187     (in_multihashtbl[(u_long)((x) ^ (ifp->if_index)) % IN_MULTI_HASH_SIZE])
188 
189 struct in_ifaddrhashhead *	in_ifaddrhashtbl;
190 u_long				in_ifaddrhash;
191 struct in_ifaddrhead		in_ifaddrhead;
192 
193 void
194 in_init(void)
195 {
196 	pool_init(&inmulti_pool, sizeof(struct in_multi), 0, 0, 0, "inmltpl",
197 	    NULL, IPL_SOFTNET);
198 	TAILQ_INIT(&in_ifaddrhead);
199 
200 	in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, true,
201 	    &in_ifaddrhash);
202 	in_multihashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, true,
203 	    &in_multihash);
204 	rw_init(&in_multilock);
205 
206 	in_sysctl_init(NULL);
207 }
208 
209 /*
210  * Return 1 if an internet address is for a ``local'' host
211  * (one to which we have a connection).  If subnetsarelocal
212  * is true, this includes other subnets of the local net.
213  * Otherwise, it includes only the directly-connected (sub)nets.
214  */
215 int
216 in_localaddr(struct in_addr in)
217 {
218 	struct in_ifaddr *ia;
219 
220 	if (subnetsarelocal) {
221 		TAILQ_FOREACH(ia, &in_ifaddrhead, ia_list)
222 			if ((in.s_addr & ia->ia_netmask) == ia->ia_net)
223 				return (1);
224 	} else {
225 		TAILQ_FOREACH(ia, &in_ifaddrhead, ia_list)
226 			if ((in.s_addr & ia->ia_subnetmask) == ia->ia_subnet)
227 				return (1);
228 	}
229 	return (0);
230 }
231 
232 /*
233  * Determine whether an IP address is in a reserved set of addresses
234  * that may not be forwarded, or whether datagrams to that destination
235  * may be forwarded.
236  */
237 int
238 in_canforward(struct in_addr in)
239 {
240 	u_int32_t net;
241 
242 	if (IN_EXPERIMENTAL(in.s_addr) || IN_MULTICAST(in.s_addr))
243 		return (0);
244 	if (IN_CLASSA(in.s_addr)) {
245 		net = in.s_addr & IN_CLASSA_NET;
246 		if (net == 0 || net == htonl(IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
247 			return (0);
248 	}
249 	return (1);
250 }
251 
252 /*
253  * Trim a mask in a sockaddr
254  */
255 void
256 in_socktrim(struct sockaddr_in *ap)
257 {
258 	char *cplim = (char *) &ap->sin_addr;
259 	char *cp = (char *) (&ap->sin_addr + 1);
260 
261 	ap->sin_len = 0;
262 	while (--cp >= cplim)
263 		if (*cp) {
264 			(ap)->sin_len = cp - (char *) (ap) + 1;
265 			break;
266 		}
267 }
268 
269 /*
270  *  Routine to take an Internet address and convert into a
271  *  "dotted quad" representation for printing.
272  */
273 const char *
274 in_fmtaddr(struct in_addr addr)
275 {
276 	static char buf[sizeof("123.456.789.123")];
277 
278 	addr.s_addr = ntohl(addr.s_addr);
279 
280 	snprintf(buf, sizeof(buf), "%d.%d.%d.%d",
281 		(addr.s_addr >> 24) & 0xFF,
282 		(addr.s_addr >> 16) & 0xFF,
283 		(addr.s_addr >>  8) & 0xFF,
284 		(addr.s_addr >>  0) & 0xFF);
285 	return buf;
286 }
287 
288 /*
289  * Maintain the "in_maxmtu" variable, which is the largest
290  * mtu for non-local interfaces with AF_INET addresses assigned
291  * to them that are up.
292  */
293 unsigned long in_maxmtu;
294 
295 void
296 in_setmaxmtu(void)
297 {
298 	struct in_ifaddr *ia;
299 	struct ifnet *ifp;
300 	unsigned long maxmtu = 0;
301 
302 	TAILQ_FOREACH(ia, &in_ifaddrhead, ia_list) {
303 		if ((ifp = ia->ia_ifp) == 0)
304 			continue;
305 		if ((ifp->if_flags & (IFF_UP|IFF_LOOPBACK)) != IFF_UP)
306 			continue;
307 		if (ifp->if_mtu > maxmtu)
308 			maxmtu = ifp->if_mtu;
309 	}
310 	if (maxmtu)
311 		in_maxmtu = maxmtu;
312 }
313 
314 static u_int
315 in_mask2len(struct in_addr *mask)
316 {
317 	u_int x, y;
318 	u_char *p;
319 
320 	p = (u_char *)mask;
321 	for (x = 0; x < sizeof(*mask); x++) {
322 		if (p[x] != 0xff)
323 			break;
324 	}
325 	y = 0;
326 	if (x < sizeof(*mask)) {
327 		for (y = 0; y < NBBY; y++) {
328 			if ((p[x] & (0x80 >> y)) == 0)
329 				break;
330 		}
331 	}
332 	return x * NBBY + y;
333 }
334 
335 static void
336 in_len2mask(struct in_addr *mask, u_int len)
337 {
338 	u_int i;
339 	u_char *p;
340 
341 	p = (u_char *)mask;
342 	memset(mask, 0, sizeof(*mask));
343 	for (i = 0; i < len / NBBY; i++)
344 		p[i] = 0xff;
345 	if (len % NBBY)
346 		p[i] = (0xff00 >> (len % NBBY)) & 0xff;
347 }
348 
349 /*
350  * Generic internet control operations (ioctl's).
351  * Ifp is 0 if not an interface-specific ioctl.
352  */
353 /* ARGSUSED */
354 int
355 in_control(struct socket *so, u_long cmd, void *data, struct ifnet *ifp)
356 {
357 	struct ifreq *ifr = (struct ifreq *)data;
358 	struct in_ifaddr *ia = NULL;
359 	struct in_aliasreq *ifra = (struct in_aliasreq *)data;
360 	struct sockaddr_in oldaddr;
361 	int error, hostIsNew, maskIsNew;
362 	int newifaddr = 0;
363 
364 	switch (cmd) {
365 	case SIOCALIFADDR:
366 	case SIOCDLIFADDR:
367 	case SIOCGLIFADDR:
368 		if (ifp == NULL)
369 			return EINVAL;
370 		return in_lifaddr_ioctl(so, cmd, data, ifp);
371 	case SIOCGIFADDRPREF:
372 	case SIOCSIFADDRPREF:
373 		if (ifp == NULL)
374 			return EINVAL;
375 		return ifaddrpref_ioctl(so, cmd, data, ifp);
376 	}
377 
378 	/*
379 	 * Find address for this interface, if it exists.
380 	 */
381 	if (ifp != NULL)
382 		IFP_TO_IA(ifp, ia);
383 
384 	hostIsNew = 1;		/* moved here to appease gcc */
385 	switch (cmd) {
386 	case SIOCAIFADDR:
387 	case SIOCDIFADDR:
388 	case SIOCGIFALIAS:
389 	case SIOCGIFAFLAG_IN:
390 		if (ifra->ifra_addr.sin_family == AF_INET)
391 			LIST_FOREACH(ia,
392 			    &IN_IFADDR_HASH(ifra->ifra_addr.sin_addr.s_addr),
393 			    ia_hash) {
394 				if (ia->ia_ifp == ifp &&
395 				    in_hosteq(ia->ia_addr.sin_addr,
396 				    ifra->ifra_addr.sin_addr))
397 					break;
398 			}
399 		if ((cmd == SIOCDIFADDR ||
400 		    cmd == SIOCGIFALIAS ||
401 		    cmd == SIOCGIFAFLAG_IN) &&
402 		    ia == NULL)
403 			return (EADDRNOTAVAIL);
404 
405 		if (cmd == SIOCDIFADDR &&
406 		    ifra->ifra_addr.sin_family == AF_UNSPEC) {
407 			ifra->ifra_addr.sin_family = AF_INET;
408 		}
409 		/* FALLTHROUGH */
410 	case SIOCSIFADDR:
411 		if (ia == NULL || ia->ia_addr.sin_family != AF_INET)
412 			;
413 		else if (ifra->ifra_addr.sin_len == 0) {
414 			ifra->ifra_addr = ia->ia_addr;
415 			hostIsNew = 0;
416 		} else if (in_hosteq(ia->ia_addr.sin_addr,
417 		           ifra->ifra_addr.sin_addr))
418 			hostIsNew = 0;
419 		/* FALLTHROUGH */
420 	case SIOCSIFDSTADDR:
421 		if (ifra->ifra_addr.sin_family != AF_INET)
422 			return (EAFNOSUPPORT);
423 		/* FALLTHROUGH */
424 	case SIOCSIFNETMASK:
425 		if (ifp == NULL)
426 			panic("in_control");
427 
428 		if (cmd == SIOCGIFALIAS || cmd == SIOCGIFAFLAG_IN)
429 			break;
430 
431 		if (ia == NULL &&
432 		    (cmd == SIOCSIFNETMASK || cmd == SIOCSIFDSTADDR))
433 			return (EADDRNOTAVAIL);
434 
435 		if (kauth_authorize_network(curlwp->l_cred, KAUTH_NETWORK_INTERFACE,
436 		    KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
437 		    NULL) != 0)
438 			return (EPERM);
439 
440 		if (ia == NULL) {
441 			ia = malloc(sizeof(*ia), M_IFADDR, M_WAITOK|M_ZERO);
442 			if (ia == NULL)
443 				return (ENOBUFS);
444 			TAILQ_INSERT_TAIL(&in_ifaddrhead, ia, ia_list);
445 			ifaref(&ia->ia_ifa);
446 			ifa_insert(ifp, &ia->ia_ifa);
447 			ia->ia_ifa.ifa_addr = sintosa(&ia->ia_addr);
448 			ia->ia_ifa.ifa_dstaddr = sintosa(&ia->ia_dstaddr);
449 			ia->ia_ifa.ifa_netmask = sintosa(&ia->ia_sockmask);
450 #ifdef IPSELSRC
451 			ia->ia_ifa.ifa_getifa = in_getifa;
452 #else /* IPSELSRC */
453 			ia->ia_ifa.ifa_getifa = NULL;
454 #endif /* IPSELSRC */
455 			ia->ia_sockmask.sin_len = 8;
456 			ia->ia_sockmask.sin_family = AF_INET;
457 			if (ifp->if_flags & IFF_BROADCAST) {
458 				ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
459 				ia->ia_broadaddr.sin_family = AF_INET;
460 			}
461 			ia->ia_ifp = ifp;
462 			ia->ia_idsalt = cprng_fast32() % 65535;
463 			LIST_INIT(&ia->ia_multiaddrs);
464 			newifaddr = 1;
465 		}
466 		break;
467 
468 	case SIOCSIFBRDADDR:
469 		if (kauth_authorize_network(curlwp->l_cred, KAUTH_NETWORK_INTERFACE,
470 		    KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
471 		    NULL) != 0)
472 			return (EPERM);
473 		/* FALLTHROUGH */
474 
475 	case SIOCGIFADDR:
476 	case SIOCGIFNETMASK:
477 	case SIOCGIFDSTADDR:
478 	case SIOCGIFBRDADDR:
479 		if (ia == NULL)
480 			return (EADDRNOTAVAIL);
481 		break;
482 	}
483 	error = 0;
484 	switch (cmd) {
485 
486 	case SIOCGIFADDR:
487 		ifreq_setaddr(cmd, ifr, sintocsa(&ia->ia_addr));
488 		break;
489 
490 	case SIOCGIFBRDADDR:
491 		if ((ifp->if_flags & IFF_BROADCAST) == 0)
492 			return (EINVAL);
493 		ifreq_setdstaddr(cmd, ifr, sintocsa(&ia->ia_broadaddr));
494 		break;
495 
496 	case SIOCGIFDSTADDR:
497 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
498 			return (EINVAL);
499 		ifreq_setdstaddr(cmd, ifr, sintocsa(&ia->ia_dstaddr));
500 		break;
501 
502 	case SIOCGIFNETMASK:
503 		/*
504 		 * We keep the number of trailing zero bytes the sin_len field
505 		 * of ia_sockmask, so we fix this before we pass it back to
506 		 * userland.
507 		 */
508 		oldaddr = ia->ia_sockmask;
509 		oldaddr.sin_len = sizeof(struct sockaddr_in);
510 		ifreq_setaddr(cmd, ifr, (const void *)&oldaddr);
511 		break;
512 
513 	case SIOCSIFDSTADDR:
514 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
515 			return (EINVAL);
516 		oldaddr = ia->ia_dstaddr;
517 		ia->ia_dstaddr = *satocsin(ifreq_getdstaddr(cmd, ifr));
518 		if ((error = if_addr_init(ifp, &ia->ia_ifa, false)) != 0) {
519 			ia->ia_dstaddr = oldaddr;
520 			return error;
521 		}
522 		if (ia->ia_flags & IFA_ROUTE) {
523 			ia->ia_ifa.ifa_dstaddr = sintosa(&oldaddr);
524 			rtinit(&ia->ia_ifa, RTM_DELETE, RTF_HOST);
525 			ia->ia_ifa.ifa_dstaddr = sintosa(&ia->ia_dstaddr);
526 			rtinit(&ia->ia_ifa, RTM_ADD, RTF_HOST|RTF_UP);
527 		}
528 		break;
529 
530 	case SIOCSIFBRDADDR:
531 		if ((ifp->if_flags & IFF_BROADCAST) == 0)
532 			return EINVAL;
533 		ia->ia_broadaddr = *satocsin(ifreq_getbroadaddr(cmd, ifr));
534 		break;
535 
536 	case SIOCSIFADDR:
537 		error = in_ifinit(ifp, ia, satocsin(ifreq_getaddr(cmd, ifr)),
538 		    1, hostIsNew);
539 		if (error == 0) {
540 			(void)pfil_run_hooks(if_pfil,
541 			    (struct mbuf **)SIOCSIFADDR, ifp, PFIL_IFADDR);
542 		}
543 		break;
544 
545 	case SIOCSIFNETMASK:
546 		in_ifscrub(ifp, ia);
547 		ia->ia_sockmask = *satocsin(ifreq_getaddr(cmd, ifr));
548 		ia->ia_subnetmask = ia->ia_sockmask.sin_addr.s_addr;
549 		error = in_ifinit(ifp, ia, NULL, 0, 0);
550 		break;
551 
552 	case SIOCAIFADDR:
553 		maskIsNew = 0;
554 		if (ifra->ifra_mask.sin_len) {
555 			/* Only scrub if we control the prefix route,
556 			 * otherwise userland gets a bogus message */
557 			if ((ia->ia_flags & IFA_ROUTE))
558 				in_ifscrub(ifp, ia);
559 			ia->ia_sockmask = ifra->ifra_mask;
560 			ia->ia_subnetmask = ia->ia_sockmask.sin_addr.s_addr;
561 			maskIsNew = 1;
562 		}
563 		if ((ifp->if_flags & IFF_POINTOPOINT) &&
564 		    (ifra->ifra_dstaddr.sin_family == AF_INET)) {
565 			/* Only scrub if we control the prefix route,
566 			 * otherwise userland gets a bogus message */
567 			if ((ia->ia_flags & IFA_ROUTE))
568 				in_ifscrub(ifp, ia);
569 			ia->ia_dstaddr = ifra->ifra_dstaddr;
570 			maskIsNew  = 1; /* We lie; but the effect's the same */
571 		}
572 		if (ifra->ifra_addr.sin_family == AF_INET &&
573 		    (hostIsNew || maskIsNew)) {
574 			error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0,
575 			    hostIsNew);
576 		}
577 		if ((ifp->if_flags & IFF_BROADCAST) &&
578 		    (ifra->ifra_broadaddr.sin_family == AF_INET))
579 			ia->ia_broadaddr = ifra->ifra_broadaddr;
580 		if (error == 0)
581 			(void)pfil_run_hooks(if_pfil,
582 			    (struct mbuf **)SIOCAIFADDR, ifp, PFIL_IFADDR);
583 		break;
584 
585 	case SIOCGIFALIAS:
586 		ifra->ifra_mask = ia->ia_sockmask;
587 		if ((ifp->if_flags & IFF_POINTOPOINT) &&
588 		    (ia->ia_dstaddr.sin_family == AF_INET))
589 			ifra->ifra_dstaddr = ia->ia_dstaddr;
590 		else if ((ifp->if_flags & IFF_BROADCAST) &&
591 		    (ia->ia_broadaddr.sin_family == AF_INET))
592 			ifra->ifra_broadaddr = ia->ia_broadaddr;
593 		else
594 			memset(&ifra->ifra_broadaddr, 0,
595 			      sizeof(ifra->ifra_broadaddr));
596 		break;
597 
598 	case SIOCGIFAFLAG_IN:
599 		ifr->ifr_addrflags = ia->ia4_flags;
600 		break;
601 
602 	case SIOCDIFADDR:
603 		in_purgeaddr(&ia->ia_ifa);
604 		(void)pfil_run_hooks(if_pfil, (struct mbuf **)SIOCDIFADDR,
605 		    ifp, PFIL_IFADDR);
606 		break;
607 
608 #ifdef MROUTING
609 	case SIOCGETVIFCNT:
610 	case SIOCGETSGCNT:
611 		error = mrt_ioctl(so, cmd, data);
612 		break;
613 #endif /* MROUTING */
614 
615 	default:
616 		return ENOTTY;
617 	}
618 
619 	if (error != 0 && newifaddr) {
620 		KASSERT(ia != NULL);
621 		in_purgeaddr(&ia->ia_ifa);
622 	}
623 
624 	return error;
625 }
626 
627 /* Add ownaddr as loopback rtentry. */
628 static void
629 in_ifaddlocal(struct ifaddr *ifa)
630 {
631 	struct in_ifaddr *ia;
632 
633 	ia = (struct in_ifaddr *)ifa;
634 	if (ia->ia_addr.sin_addr.s_addr == INADDR_ANY ||
635 	    (ia->ia_ifp->if_flags & IFF_POINTOPOINT &&
636 	    in_hosteq(ia->ia_dstaddr.sin_addr, ia->ia_addr.sin_addr)))
637 	{
638 		rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL);
639 		return;
640 	}
641 
642 	rt_ifa_addlocal(ifa);
643 }
644 
645 /* Rempve loopback entry of ownaddr */
646 static void
647 in_ifremlocal(struct ifaddr *ifa)
648 {
649 	struct in_ifaddr *ia, *p;
650 	struct ifaddr *alt_ifa = NULL;
651 	int ia_count = 0;
652 
653 	ia = (struct in_ifaddr *)ifa;
654 	/* Delete the entry if exactly one ifaddr matches the
655 	 * address, ifa->ifa_addr. */
656 	TAILQ_FOREACH(p, &in_ifaddrhead, ia_list) {
657 		if (!in_hosteq(p->ia_addr.sin_addr, ia->ia_addr.sin_addr))
658 			continue;
659 		if (p->ia_ifp != ia->ia_ifp)
660 			alt_ifa = &p->ia_ifa;
661 		if (++ia_count > 1 && alt_ifa != NULL)
662 			break;
663 	}
664 
665 	if (ia_count == 0)
666 		return;
667 
668 	rt_ifa_remlocal(ifa, ia_count == 1 ? NULL : alt_ifa);
669 }
670 
671 void
672 in_purgeaddr(struct ifaddr *ifa)
673 {
674 	struct ifnet *ifp = ifa->ifa_ifp;
675 	struct in_ifaddr *ia = (void *) ifa;
676 
677 	/* stop DAD processing */
678 	if (ia->ia_dad_stop != NULL)
679 		ia->ia_dad_stop(ifa);
680 
681 	in_ifscrub(ifp, ia);
682 	in_ifremlocal(ifa);
683 	LIST_REMOVE(ia, ia_hash);
684 	ifa_remove(ifp, &ia->ia_ifa);
685 	TAILQ_REMOVE(&in_ifaddrhead, ia, ia_list);
686 	if (ia->ia_allhosts != NULL)
687 		in_delmulti(ia->ia_allhosts);
688 	ifafree(&ia->ia_ifa);
689 	in_setmaxmtu();
690 }
691 
692 void
693 in_purgeif(struct ifnet *ifp)		/* MUST be called at splsoftnet() */
694 {
695 	if_purgeaddrs(ifp, AF_INET, in_purgeaddr);
696 	igmp_purgeif(ifp);		/* manipulates pools */
697 #ifdef MROUTING
698 	ip_mrouter_detach(ifp);
699 #endif
700 }
701 
702 /*
703  * SIOC[GAD]LIFADDR.
704  *	SIOCGLIFADDR: get first address. (???)
705  *	SIOCGLIFADDR with IFLR_PREFIX:
706  *		get first address that matches the specified prefix.
707  *	SIOCALIFADDR: add the specified address.
708  *	SIOCALIFADDR with IFLR_PREFIX:
709  *		EINVAL since we can't deduce hostid part of the address.
710  *	SIOCDLIFADDR: delete the specified address.
711  *	SIOCDLIFADDR with IFLR_PREFIX:
712  *		delete the first address that matches the specified prefix.
713  * return values:
714  *	EINVAL on invalid parameters
715  *	EADDRNOTAVAIL on prefix match failed/specified address not found
716  *	other values may be returned from in_ioctl()
717  */
718 static int
719 in_lifaddr_ioctl(struct socket *so, u_long cmd, void *data,
720     struct ifnet *ifp)
721 {
722 	struct if_laddrreq *iflr = (struct if_laddrreq *)data;
723 	struct ifaddr *ifa;
724 	struct sockaddr *sa;
725 
726 	/* sanity checks */
727 	if (data == NULL || ifp == NULL) {
728 		panic("invalid argument to in_lifaddr_ioctl");
729 		/*NOTRECHED*/
730 	}
731 
732 	switch (cmd) {
733 	case SIOCGLIFADDR:
734 		/* address must be specified on GET with IFLR_PREFIX */
735 		if ((iflr->flags & IFLR_PREFIX) == 0)
736 			break;
737 		/*FALLTHROUGH*/
738 	case SIOCALIFADDR:
739 	case SIOCDLIFADDR:
740 		/* address must be specified on ADD and DELETE */
741 		sa = (struct sockaddr *)&iflr->addr;
742 		if (sa->sa_family != AF_INET)
743 			return EINVAL;
744 		if (sa->sa_len != sizeof(struct sockaddr_in))
745 			return EINVAL;
746 		/* XXX need improvement */
747 		sa = (struct sockaddr *)&iflr->dstaddr;
748 		if (sa->sa_family != AF_UNSPEC && sa->sa_family != AF_INET)
749 			return EINVAL;
750 		if (sa->sa_len != 0 && sa->sa_len != sizeof(struct sockaddr_in))
751 			return EINVAL;
752 		break;
753 	default: /*shouldn't happen*/
754 #if 0
755 		panic("invalid cmd to in_lifaddr_ioctl");
756 		/*NOTREACHED*/
757 #else
758 		return EOPNOTSUPP;
759 #endif
760 	}
761 	if (sizeof(struct in_addr) * NBBY < iflr->prefixlen)
762 		return EINVAL;
763 
764 	switch (cmd) {
765 	case SIOCALIFADDR:
766 	    {
767 		struct in_aliasreq ifra;
768 
769 		if (iflr->flags & IFLR_PREFIX)
770 			return EINVAL;
771 
772 		/* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR). */
773 		memset(&ifra, 0, sizeof(ifra));
774 		memcpy(ifra.ifra_name, iflr->iflr_name,
775 			sizeof(ifra.ifra_name));
776 
777 		memcpy(&ifra.ifra_addr, &iflr->addr,
778 			((struct sockaddr *)&iflr->addr)->sa_len);
779 
780 		if (((struct sockaddr *)&iflr->dstaddr)->sa_family) {	/*XXX*/
781 			memcpy(&ifra.ifra_dstaddr, &iflr->dstaddr,
782 				((struct sockaddr *)&iflr->dstaddr)->sa_len);
783 		}
784 
785 		ifra.ifra_mask.sin_family = AF_INET;
786 		ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
787 		in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);
788 
789 		return in_control(so, SIOCAIFADDR, &ifra, ifp);
790 	    }
791 	case SIOCGLIFADDR:
792 	case SIOCDLIFADDR:
793 	    {
794 		struct in_ifaddr *ia;
795 		struct in_addr mask, candidate, match;
796 		struct sockaddr_in *sin;
797 		int cmp;
798 
799 		memset(&mask, 0, sizeof(mask));
800 		memset(&match, 0, sizeof(match));	/* XXX gcc */
801 		if (iflr->flags & IFLR_PREFIX) {
802 			/* lookup a prefix rather than address. */
803 			in_len2mask(&mask, iflr->prefixlen);
804 
805 			sin = (struct sockaddr_in *)&iflr->addr;
806 			match.s_addr = sin->sin_addr.s_addr;
807 			match.s_addr &= mask.s_addr;
808 
809 			/* if you set extra bits, that's wrong */
810 			if (match.s_addr != sin->sin_addr.s_addr)
811 				return EINVAL;
812 
813 			cmp = 1;
814 		} else {
815 			if (cmd == SIOCGLIFADDR) {
816 				/* on getting an address, take the 1st match */
817 				cmp = 0;	/*XXX*/
818 			} else {
819 				/* on deleting an address, do exact match */
820 				in_len2mask(&mask, 32);
821 				sin = (struct sockaddr_in *)&iflr->addr;
822 				match.s_addr = sin->sin_addr.s_addr;
823 
824 				cmp = 1;
825 			}
826 		}
827 
828 		IFADDR_FOREACH(ifa, ifp) {
829 			if (ifa->ifa_addr->sa_family != AF_INET)
830 				continue;
831 			if (cmp == 0)
832 				break;
833 			candidate.s_addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr;
834 			candidate.s_addr &= mask.s_addr;
835 			if (candidate.s_addr == match.s_addr)
836 				break;
837 		}
838 		if (ifa == NULL)
839 			return EADDRNOTAVAIL;
840 		ia = (struct in_ifaddr *)ifa;
841 
842 		if (cmd == SIOCGLIFADDR) {
843 			/* fill in the if_laddrreq structure */
844 			memcpy(&iflr->addr, &ia->ia_addr, ia->ia_addr.sin_len);
845 
846 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
847 				memcpy(&iflr->dstaddr, &ia->ia_dstaddr,
848 					ia->ia_dstaddr.sin_len);
849 			} else
850 				memset(&iflr->dstaddr, 0, sizeof(iflr->dstaddr));
851 
852 			iflr->prefixlen =
853 				in_mask2len(&ia->ia_sockmask.sin_addr);
854 
855 			iflr->flags = 0;	/*XXX*/
856 
857 			return 0;
858 		} else {
859 			struct in_aliasreq ifra;
860 
861 			/* fill in_aliasreq and do ioctl(SIOCDIFADDR) */
862 			memset(&ifra, 0, sizeof(ifra));
863 			memcpy(ifra.ifra_name, iflr->iflr_name,
864 				sizeof(ifra.ifra_name));
865 
866 			memcpy(&ifra.ifra_addr, &ia->ia_addr,
867 				ia->ia_addr.sin_len);
868 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
869 				memcpy(&ifra.ifra_dstaddr, &ia->ia_dstaddr,
870 					ia->ia_dstaddr.sin_len);
871 			}
872 			memcpy(&ifra.ifra_dstaddr, &ia->ia_sockmask,
873 				ia->ia_sockmask.sin_len);
874 
875 			return in_control(so, SIOCDIFADDR, &ifra, ifp);
876 		}
877 	    }
878 	}
879 
880 	return EOPNOTSUPP;	/*just for safety*/
881 }
882 
883 /*
884  * Delete any existing route for an interface.
885  */
886 void
887 in_ifscrub(struct ifnet *ifp, struct in_ifaddr *ia)
888 {
889 
890 	in_scrubprefix(ia);
891 }
892 
893 /*
894  * Initialize an interface's internet address
895  * and routing table entry.
896  */
897 int
898 in_ifinit(struct ifnet *ifp, struct in_ifaddr *ia,
899     const struct sockaddr_in *sin, int scrub, int hostIsNew)
900 {
901 	u_int32_t i;
902 	struct sockaddr_in oldaddr;
903 	int s = splnet(), flags = RTF_UP, error;
904 
905 	if (sin == NULL)
906 		sin = &ia->ia_addr;
907 
908 	/*
909 	 * Set up new addresses.
910 	 */
911 	oldaddr = ia->ia_addr;
912 	if (ia->ia_addr.sin_family == AF_INET)
913 		LIST_REMOVE(ia, ia_hash);
914 	ia->ia_addr = *sin;
915 	LIST_INSERT_HEAD(&IN_IFADDR_HASH(ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
916 
917 	/* Set IN_IFF flags early for if_addr_init() */
918 	if (hostIsNew && if_do_dad(ifp) && !in_nullhost(ia->ia_addr.sin_addr)) {
919 		if (ifp->if_link_state == LINK_STATE_DOWN)
920 			ia->ia4_flags |= IN_IFF_DETACHED;
921 		else
922 			/* State the intent to try DAD if possible */
923 			ia->ia4_flags |= IN_IFF_TRYTENTATIVE;
924 	}
925 
926 	/*
927 	 * Give the interface a chance to initialize
928 	 * if this is its first address,
929 	 * and to validate the address if necessary.
930 	 */
931 	if ((error = if_addr_init(ifp, &ia->ia_ifa, true)) != 0)
932 		goto bad;
933 	/* Now clear the try tentative flag, it's job is done. */
934 	ia->ia4_flags &= ~IN_IFF_TRYTENTATIVE;
935 	splx(s);
936 
937 	if (scrub) {
938 		ia->ia_ifa.ifa_addr = sintosa(&oldaddr);
939 		in_ifscrub(ifp, ia);
940 		ia->ia_ifa.ifa_addr = sintosa(&ia->ia_addr);
941 	}
942 
943 	/* Add the local route to the address */
944 	in_ifaddlocal(&ia->ia_ifa);
945 
946 	i = ia->ia_addr.sin_addr.s_addr;
947 	if (IN_CLASSA(i))
948 		ia->ia_netmask = IN_CLASSA_NET;
949 	else if (IN_CLASSB(i))
950 		ia->ia_netmask = IN_CLASSB_NET;
951 	else
952 		ia->ia_netmask = IN_CLASSC_NET;
953 	/*
954 	 * The subnet mask usually includes at least the standard network part,
955 	 * but may may be smaller in the case of supernetting.
956 	 * If it is set, we believe it.
957 	 */
958 	if (ia->ia_subnetmask == 0) {
959 		ia->ia_subnetmask = ia->ia_netmask;
960 		ia->ia_sockmask.sin_addr.s_addr = ia->ia_subnetmask;
961 	} else
962 		ia->ia_netmask &= ia->ia_subnetmask;
963 
964 	ia->ia_net = i & ia->ia_netmask;
965 	ia->ia_subnet = i & ia->ia_subnetmask;
966 	in_socktrim(&ia->ia_sockmask);
967 	/* re-calculate the "in_maxmtu" value */
968 	in_setmaxmtu();
969 	/*
970 	 * Add route for the network.
971 	 */
972 	ia->ia_ifa.ifa_metric = ifp->if_metric;
973 	if (ifp->if_flags & IFF_BROADCAST) {
974 		ia->ia_broadaddr.sin_addr.s_addr =
975 			ia->ia_subnet | ~ia->ia_subnetmask;
976 		ia->ia_netbroadcast.s_addr =
977 			ia->ia_net | ~ia->ia_netmask;
978 	} else if (ifp->if_flags & IFF_LOOPBACK) {
979 		ia->ia_dstaddr = ia->ia_addr;
980 		flags |= RTF_HOST;
981 	} else if (ifp->if_flags & IFF_POINTOPOINT) {
982 		if (ia->ia_dstaddr.sin_family != AF_INET)
983 			return (0);
984 		flags |= RTF_HOST;
985 	}
986 	error = in_addprefix(ia, flags);
987 	/*
988 	 * If the interface supports multicast, join the "all hosts"
989 	 * multicast group on that interface.
990 	 */
991 	if ((ifp->if_flags & IFF_MULTICAST) != 0 && ia->ia_allhosts == NULL) {
992 		struct in_addr addr;
993 
994 		addr.s_addr = INADDR_ALLHOSTS_GROUP;
995 		ia->ia_allhosts = in_addmulti(&addr, ifp);
996 	}
997 
998 	if (hostIsNew && if_do_dad(ifp) &&
999 	    !in_nullhost(ia->ia_addr.sin_addr) &&
1000 	    ia->ia4_flags & IN_IFF_TENTATIVE)
1001 		ia->ia_dad_start((struct ifaddr *)ia);
1002 
1003 	return (error);
1004 bad:
1005 	splx(s);
1006 	LIST_REMOVE(ia, ia_hash);
1007 	ia->ia_addr = oldaddr;
1008 	if (ia->ia_addr.sin_family == AF_INET)
1009 		LIST_INSERT_HEAD(&IN_IFADDR_HASH(ia->ia_addr.sin_addr.s_addr),
1010 		    ia, ia_hash);
1011 	return (error);
1012 }
1013 
1014 #define rtinitflags(x) \
1015 	((((x)->ia_ifp->if_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) != 0) \
1016 	    ? RTF_HOST : 0)
1017 
1018 /*
1019  * add a route to prefix ("connected route" in cisco terminology).
1020  * does nothing if there's some interface address with the same prefix already.
1021  */
1022 static int
1023 in_addprefix(struct in_ifaddr *target, int flags)
1024 {
1025 	struct in_ifaddr *ia;
1026 	struct in_addr prefix, mask, p;
1027 	int error;
1028 
1029 	if ((flags & RTF_HOST) != 0)
1030 		prefix = target->ia_dstaddr.sin_addr;
1031 	else {
1032 		prefix = target->ia_addr.sin_addr;
1033 		mask = target->ia_sockmask.sin_addr;
1034 		prefix.s_addr &= mask.s_addr;
1035 	}
1036 
1037 	TAILQ_FOREACH(ia, &in_ifaddrhead, ia_list) {
1038 		if (rtinitflags(ia))
1039 			p = ia->ia_dstaddr.sin_addr;
1040 		else {
1041 			p = ia->ia_addr.sin_addr;
1042 			p.s_addr &= ia->ia_sockmask.sin_addr.s_addr;
1043 		}
1044 
1045 		if (prefix.s_addr != p.s_addr)
1046 			continue;
1047 
1048 		/*
1049 		 * if we got a matching prefix route inserted by other
1050 		 * interface address, we don't need to bother
1051 		 *
1052 		 * XXX RADIX_MPATH implications here? -dyoung
1053 		 */
1054 		if (ia->ia_flags & IFA_ROUTE)
1055 			return 0;
1056 	}
1057 
1058 	/*
1059 	 * noone seem to have prefix route.  insert it.
1060 	 */
1061 	error = rtinit(&target->ia_ifa, RTM_ADD, flags);
1062 	if (error == 0)
1063 		target->ia_flags |= IFA_ROUTE;
1064 	else if (error == EEXIST) {
1065 		/*
1066 		 * the fact the route already exists is not an error.
1067 		 */
1068 		error = 0;
1069 	}
1070 	return error;
1071 }
1072 
1073 /*
1074  * remove a route to prefix ("connected route" in cisco terminology).
1075  * re-installs the route by using another interface address, if there's one
1076  * with the same prefix (otherwise we lose the route mistakenly).
1077  */
1078 static int
1079 in_scrubprefix(struct in_ifaddr *target)
1080 {
1081 	struct in_ifaddr *ia;
1082 	struct in_addr prefix, mask, p;
1083 	int error;
1084 
1085 	/* If we don't have IFA_ROUTE we should still inform userland */
1086 	if ((target->ia_flags & IFA_ROUTE) == 0)
1087 		return 0;
1088 
1089 	if (rtinitflags(target))
1090 		prefix = target->ia_dstaddr.sin_addr;
1091 	else {
1092 		prefix = target->ia_addr.sin_addr;
1093 		mask = target->ia_sockmask.sin_addr;
1094 		prefix.s_addr &= mask.s_addr;
1095 	}
1096 
1097 	TAILQ_FOREACH(ia, &in_ifaddrhead, ia_list) {
1098 		if (rtinitflags(ia))
1099 			p = ia->ia_dstaddr.sin_addr;
1100 		else {
1101 			p = ia->ia_addr.sin_addr;
1102 			p.s_addr &= ia->ia_sockmask.sin_addr.s_addr;
1103 		}
1104 
1105 		if (prefix.s_addr != p.s_addr)
1106 			continue;
1107 
1108 		/*
1109 		 * if we got a matching prefix route, move IFA_ROUTE to him
1110 		 */
1111 		if ((ia->ia_flags & IFA_ROUTE) == 0) {
1112 			rtinit(&target->ia_ifa, RTM_DELETE,
1113 			    rtinitflags(target));
1114 			target->ia_flags &= ~IFA_ROUTE;
1115 
1116 			error = rtinit(&ia->ia_ifa, RTM_ADD,
1117 			    rtinitflags(ia) | RTF_UP);
1118 			if (error == 0)
1119 				ia->ia_flags |= IFA_ROUTE;
1120 			return error;
1121 		}
1122 	}
1123 
1124 	/*
1125 	 * noone seem to have prefix route.  remove it.
1126 	 */
1127 	rtinit(&target->ia_ifa, RTM_DELETE, rtinitflags(target));
1128 	target->ia_flags &= ~IFA_ROUTE;
1129 	return 0;
1130 }
1131 
1132 #undef rtinitflags
1133 
1134 /*
1135  * Return 1 if the address might be a local broadcast address.
1136  */
1137 int
1138 in_broadcast(struct in_addr in, struct ifnet *ifp)
1139 {
1140 	struct ifaddr *ifa;
1141 
1142 	if (in.s_addr == INADDR_BROADCAST ||
1143 	    in_nullhost(in))
1144 		return 1;
1145 	if ((ifp->if_flags & IFF_BROADCAST) == 0)
1146 		return 0;
1147 	/*
1148 	 * Look through the list of addresses for a match
1149 	 * with a broadcast address.
1150 	 */
1151 #define ia (ifatoia(ifa))
1152 	IFADDR_FOREACH(ifa, ifp)
1153 		if (ifa->ifa_addr->sa_family == AF_INET &&
1154 		    !in_hosteq(in, ia->ia_addr.sin_addr) &&
1155 		    (in_hosteq(in, ia->ia_broadaddr.sin_addr) ||
1156 		     in_hosteq(in, ia->ia_netbroadcast) ||
1157 		     (hostzeroisbroadcast &&
1158 		      /*
1159 		       * Check for old-style (host 0) broadcast.
1160 		       */
1161 		      (in.s_addr == ia->ia_subnet ||
1162 		       in.s_addr == ia->ia_net))))
1163 			return 1;
1164 	return (0);
1165 #undef ia
1166 }
1167 
1168 /*
1169  * perform DAD when interface becomes IFF_UP.
1170  */
1171 void
1172 in_if_link_up(struct ifnet *ifp)
1173 {
1174 	struct ifaddr *ifa;
1175 	struct in_ifaddr *ia;
1176 
1177 	/* Ensure it's sane to run DAD */
1178 	if (ifp->if_link_state == LINK_STATE_DOWN)
1179 		return;
1180 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
1181 		return;
1182 
1183 	IFADDR_FOREACH(ifa, ifp) {
1184 		if (ifa->ifa_addr->sa_family != AF_INET)
1185 			continue;
1186 		ia = (struct in_ifaddr *)ifa;
1187 
1188 		/* If detached then mark as tentative */
1189 		if (ia->ia4_flags & IN_IFF_DETACHED) {
1190 			ia->ia4_flags &= ~IN_IFF_DETACHED;
1191 			if (if_do_dad(ifp) && ia->ia_dad_start != NULL)
1192 				ia->ia4_flags |= IN_IFF_TENTATIVE;
1193 			else if ((ia->ia4_flags & IN_IFF_TENTATIVE) == 0)
1194 				rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL);
1195 		}
1196 
1197 		if (ia->ia4_flags & IN_IFF_TENTATIVE) {
1198 			/* Clear the duplicated flag as we're starting DAD. */
1199 			ia->ia4_flags &= ~IN_IFF_DUPLICATED;
1200 			ia->ia_dad_start(ifa);
1201 		}
1202 	}
1203 }
1204 
1205 void
1206 in_if_up(struct ifnet *ifp)
1207 {
1208 
1209 	/* interface may not support link state, so bring it up also */
1210 	in_if_link_up(ifp);
1211 }
1212 
1213 /*
1214  * Mark all addresses as detached.
1215  */
1216 void
1217 in_if_link_down(struct ifnet *ifp)
1218 {
1219 	struct ifaddr *ifa;
1220 	struct in_ifaddr *ia;
1221 
1222 	IFADDR_FOREACH(ifa, ifp) {
1223 		if (ifa->ifa_addr->sa_family != AF_INET)
1224 			continue;
1225 		ia = (struct in_ifaddr *)ifa;
1226 
1227 		/* Stop DAD processing */
1228 		if (ia->ia_dad_stop != NULL)
1229 			ia->ia_dad_stop(ifa);
1230 
1231 		/*
1232 		 * Mark the address as detached.
1233 		 */
1234 		if (!(ia->ia4_flags & IN_IFF_DETACHED)) {
1235 			ia->ia4_flags |= IN_IFF_DETACHED;
1236 			ia->ia4_flags &=
1237 			    ~(IN_IFF_TENTATIVE | IN_IFF_DUPLICATED);
1238 			rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL);
1239 		}
1240 	}
1241 }
1242 
1243 void
1244 in_if_down(struct ifnet *ifp)
1245 {
1246 
1247 	in_if_link_down(ifp);
1248 }
1249 
1250 void
1251 in_if_link_state_change(struct ifnet *ifp, int link_state)
1252 {
1253 
1254 	switch (link_state) {
1255 	case LINK_STATE_DOWN:
1256 		in_if_link_down(ifp);
1257 		break;
1258 	case LINK_STATE_UP:
1259 		in_if_link_up(ifp);
1260 		break;
1261 	}
1262 }
1263 
1264 /*
1265  * in_lookup_multi: look up the in_multi record for a given IP
1266  * multicast address on a given interface.  If no matching record is
1267  * found, return NULL.
1268  */
1269 struct in_multi *
1270 in_lookup_multi(struct in_addr addr, ifnet_t *ifp)
1271 {
1272 	struct in_multi *inm;
1273 
1274 	KASSERT(rw_lock_held(&in_multilock));
1275 
1276 	LIST_FOREACH(inm, &IN_MULTI_HASH(addr.s_addr, ifp), inm_list) {
1277 		if (in_hosteq(inm->inm_addr, addr) && inm->inm_ifp == ifp)
1278 			break;
1279 	}
1280 	return inm;
1281 }
1282 
1283 /*
1284  * in_multi_group: check whether the address belongs to an IP multicast
1285  * group we are joined on this interface.  Returns true or false.
1286  */
1287 bool
1288 in_multi_group(struct in_addr addr, ifnet_t *ifp, int flags)
1289 {
1290 	bool ingroup;
1291 
1292 	if (__predict_true(flags & IP_IGMP_MCAST) == 0) {
1293 		rw_enter(&in_multilock, RW_READER);
1294 		ingroup = in_lookup_multi(addr, ifp) != NULL;
1295 		rw_exit(&in_multilock);
1296 	} else {
1297 		/* XXX Recursive call from ip_output(). */
1298 		KASSERT(rw_lock_held(&in_multilock));
1299 		ingroup = in_lookup_multi(addr, ifp) != NULL;
1300 	}
1301 	return ingroup;
1302 }
1303 
1304 /*
1305  * Add an address to the list of IP multicast addresses for a given interface.
1306  */
1307 struct in_multi *
1308 in_addmulti(struct in_addr *ap, ifnet_t *ifp)
1309 {
1310 	struct sockaddr_in sin;
1311 	struct in_multi *inm;
1312 
1313 	/*
1314 	 * See if address already in list.
1315 	 */
1316 	rw_enter(&in_multilock, RW_WRITER);
1317 	inm = in_lookup_multi(*ap, ifp);
1318 	if (inm != NULL) {
1319 		/*
1320 		 * Found it; just increment the reference count.
1321 		 */
1322 		inm->inm_refcount++;
1323 		rw_exit(&in_multilock);
1324 		return inm;
1325 	}
1326 
1327 	/*
1328 	 * New address; allocate a new multicast record.
1329 	 */
1330 	inm = pool_get(&inmulti_pool, PR_NOWAIT);
1331 	if (inm == NULL) {
1332 		rw_exit(&in_multilock);
1333 		return NULL;
1334 	}
1335 	inm->inm_addr = *ap;
1336 	inm->inm_ifp = ifp;
1337 	inm->inm_refcount = 1;
1338 
1339 	/*
1340 	 * Ask the network driver to update its multicast reception
1341 	 * filter appropriately for the new address.
1342 	 */
1343 	sockaddr_in_init(&sin, ap, 0);
1344 	if (if_mcast_op(ifp, SIOCADDMULTI, sintosa(&sin)) != 0) {
1345 		rw_exit(&in_multilock);
1346 		pool_put(&inmulti_pool, inm);
1347 		return NULL;
1348 	}
1349 
1350 	/*
1351 	 * Let IGMP know that we have joined a new IP multicast group.
1352 	 */
1353 	if (igmp_joingroup(inm) != 0) {
1354 		rw_exit(&in_multilock);
1355 		pool_put(&inmulti_pool, inm);
1356 		return NULL;
1357 	}
1358 	LIST_INSERT_HEAD(
1359 	    &IN_MULTI_HASH(inm->inm_addr.s_addr, ifp),
1360 	    inm, inm_list);
1361 	in_multientries++;
1362 	rw_exit(&in_multilock);
1363 
1364 	return inm;
1365 }
1366 
1367 /*
1368  * Delete a multicast address record.
1369  */
1370 void
1371 in_delmulti(struct in_multi *inm)
1372 {
1373 	struct sockaddr_in sin;
1374 
1375 	rw_enter(&in_multilock, RW_WRITER);
1376 	if (--inm->inm_refcount > 0) {
1377 		rw_exit(&in_multilock);
1378 		return;
1379 	}
1380 
1381 	/*
1382 	 * No remaining claims to this record; let IGMP know that
1383 	 * we are leaving the multicast group.
1384 	 */
1385 	igmp_leavegroup(inm);
1386 
1387 	/*
1388 	 * Notify the network driver to update its multicast reception
1389 	 * filter.
1390 	 */
1391 	sockaddr_in_init(&sin, &inm->inm_addr, 0);
1392 	if_mcast_op(inm->inm_ifp, SIOCDELMULTI, sintosa(&sin));
1393 
1394 	/*
1395 	 * Unlink from list.
1396 	 */
1397 	LIST_REMOVE(inm, inm_list);
1398 	in_multientries--;
1399 	rw_exit(&in_multilock);
1400 
1401 	pool_put(&inmulti_pool, inm);
1402 }
1403 
1404 /*
1405  * in_next_multi: step through all of the in_multi records, one at a time.
1406  * The current position is remembered in "step", which the caller must
1407  * provide.  in_first_multi(), below, must be called to initialize "step"
1408  * and get the first record.  Both macros return a NULL "inm" when there
1409  * are no remaining records.
1410  */
1411 struct in_multi *
1412 in_next_multi(struct in_multistep *step)
1413 {
1414 	struct in_multi *inm;
1415 
1416 	KASSERT(rw_lock_held(&in_multilock));
1417 
1418 	while (step->i_inm == NULL && step->i_n < IN_MULTI_HASH_SIZE) {
1419 		step->i_inm = LIST_FIRST(&in_multihashtbl[++step->i_n]);
1420 	}
1421 	if ((inm = step->i_inm) != NULL) {
1422 		step->i_inm = LIST_NEXT(inm, inm_list);
1423 	}
1424 	return inm;
1425 }
1426 
1427 struct in_multi *
1428 in_first_multi(struct in_multistep *step)
1429 {
1430 	KASSERT(rw_lock_held(&in_multilock));
1431 
1432 	step->i_n = 0;
1433 	step->i_inm = LIST_FIRST(&in_multihashtbl[0]);
1434 	return in_next_multi(step);
1435 }
1436 
1437 void
1438 in_multi_lock(int op)
1439 {
1440 	rw_enter(&in_multilock, op);
1441 }
1442 
1443 void
1444 in_multi_unlock(void)
1445 {
1446 	rw_exit(&in_multilock);
1447 }
1448 
1449 int
1450 in_multi_lock_held(void)
1451 {
1452 	return rw_lock_held(&in_multilock);
1453 }
1454 
1455 struct sockaddr_in *
1456 in_selectsrc(struct sockaddr_in *sin, struct route *ro,
1457     int soopts, struct ip_moptions *mopts, int *errorp)
1458 {
1459 	struct rtentry *rt = NULL;
1460 	struct in_ifaddr *ia = NULL;
1461 
1462 	/*
1463          * If route is known or can be allocated now, take the
1464          * source address from the interface.  Otherwise, punt.
1465 	 */
1466 	if ((soopts & SO_DONTROUTE) != 0)
1467 		rtcache_free(ro);
1468 	else {
1469 		union {
1470 			struct sockaddr		dst;
1471 			struct sockaddr_in	dst4;
1472 		} u;
1473 
1474 		sockaddr_in_init(&u.dst4, &sin->sin_addr, 0);
1475 		rt = rtcache_lookup(ro, &u.dst);
1476 	}
1477 	/*
1478 	 * If we found a route, use the address
1479 	 * corresponding to the outgoing interface
1480 	 * unless it is the loopback (in case a route
1481 	 * to our address on another net goes to loopback).
1482 	 *
1483 	 * XXX Is this still true?  Do we care?
1484 	 */
1485 	if (rt != NULL && (rt->rt_ifp->if_flags & IFF_LOOPBACK) == 0)
1486 		ia = ifatoia(rt->rt_ifa);
1487 	if (ia == NULL) {
1488 		u_int16_t fport = sin->sin_port;
1489 
1490 		sin->sin_port = 0;
1491 		ia = ifatoia(ifa_ifwithladdr(sintosa(sin)));
1492 		sin->sin_port = fport;
1493 		if (ia == NULL) {
1494 			/* Find 1st non-loopback AF_INET address */
1495 			TAILQ_FOREACH(ia, &in_ifaddrhead, ia_list) {
1496 				if (!(ia->ia_ifp->if_flags & IFF_LOOPBACK))
1497 					break;
1498 			}
1499 		}
1500 		if (ia == NULL) {
1501 			*errorp = EADDRNOTAVAIL;
1502 			return NULL;
1503 		}
1504 	}
1505 	/*
1506 	 * If the destination address is multicast and an outgoing
1507 	 * interface has been set as a multicast option, use the
1508 	 * address of that interface as our source address.
1509 	 */
1510 	if (IN_MULTICAST(sin->sin_addr.s_addr) && mopts != NULL) {
1511 		struct ip_moptions *imo;
1512 		struct ifnet *ifp;
1513 
1514 		imo = mopts;
1515 		if (imo->imo_multicast_ifp != NULL) {
1516 			ifp = imo->imo_multicast_ifp;
1517 			IFP_TO_IA(ifp, ia);		/* XXX */
1518 			if (ia == 0 || ia->ia4_flags & IN_IFF_NOTREADY) {
1519 				*errorp = EADDRNOTAVAIL;
1520 				return NULL;
1521 			}
1522 		}
1523 	}
1524 	if (ia->ia_ifa.ifa_getifa != NULL) {
1525 		ia = ifatoia((*ia->ia_ifa.ifa_getifa)(&ia->ia_ifa,
1526 		                                      sintosa(sin)));
1527 		if (ia == NULL) {
1528 			*errorp = EADDRNOTAVAIL;
1529 			return NULL;
1530 		}
1531 	}
1532 #ifdef GETIFA_DEBUG
1533 	else
1534 		printf("%s: missing ifa_getifa\n", __func__);
1535 #endif
1536 	return satosin(&ia->ia_addr);
1537 }
1538 
1539 #if NETHER > 0
1540 
1541 struct in_llentry {
1542 	struct llentry		base;
1543 };
1544 
1545 #define	IN_LLTBL_DEFAULT_HSIZE	32
1546 #define	IN_LLTBL_HASH(k, h) \
1547 	(((((((k >> 8) ^ k) >> 8) ^ k) >> 8) ^ k) & ((h) - 1))
1548 
1549 /*
1550  * Do actual deallocation of @lle.
1551  * Called by LLE_FREE_LOCKED when number of references
1552  * drops to zero.
1553  */
1554 static void
1555 in_lltable_destroy_lle(struct llentry *lle)
1556 {
1557 
1558 	LLE_WUNLOCK(lle);
1559 	LLE_LOCK_DESTROY(lle);
1560 	kmem_intr_free(lle, sizeof(*lle));
1561 }
1562 
1563 static struct llentry *
1564 in_lltable_new(struct in_addr addr4, u_int flags)
1565 {
1566 	struct in_llentry *lle;
1567 
1568 	lle = kmem_intr_zalloc(sizeof(*lle), KM_NOSLEEP);
1569 	if (lle == NULL)		/* NB: caller generates msg */
1570 		return NULL;
1571 
1572 	/*
1573 	 * For IPv4 this will trigger "arpresolve" to generate
1574 	 * an ARP request.
1575 	 */
1576 	lle->base.la_expire = time_uptime; /* mark expired */
1577 	lle->base.r_l3addr.addr4 = addr4;
1578 	lle->base.lle_refcnt = 1;
1579 	lle->base.lle_free = in_lltable_destroy_lle;
1580 	LLE_LOCK_INIT(&lle->base);
1581 	callout_init(&lle->base.la_timer, CALLOUT_MPSAFE);
1582 
1583 	return (&lle->base);
1584 }
1585 
1586 #define IN_ARE_MASKED_ADDR_EQUAL(d, a, m)	(			\
1587 	    (((ntohl((d).s_addr) ^ (a)->sin_addr.s_addr) & (m)->sin_addr.s_addr)) == 0 )
1588 
1589 static int
1590 in_lltable_match_prefix(const struct sockaddr *prefix,
1591     const struct sockaddr *mask, u_int flags, struct llentry *lle)
1592 {
1593 	const struct sockaddr_in *pfx = (const struct sockaddr_in *)prefix;
1594 	const struct sockaddr_in *msk = (const struct sockaddr_in *)mask;
1595 
1596 	/*
1597 	 * (flags & LLE_STATIC) means deleting all entries
1598 	 * including static ARP entries.
1599 	 */
1600 	if (IN_ARE_MASKED_ADDR_EQUAL(lle->r_l3addr.addr4, pfx, msk) &&
1601 	    ((flags & LLE_STATIC) || !(lle->la_flags & LLE_STATIC)))
1602 		return (1);
1603 
1604 	return (0);
1605 }
1606 
1607 static void
1608 in_lltable_free_entry(struct lltable *llt, struct llentry *lle)
1609 {
1610 	struct ifnet *ifp __diagused;
1611 	size_t pkts_dropped;
1612 
1613 	LLE_WLOCK_ASSERT(lle);
1614 	KASSERT(llt != NULL);
1615 
1616 	/* Unlink entry from table if not already */
1617 	if ((lle->la_flags & LLE_LINKED) != 0) {
1618 		ifp = llt->llt_ifp;
1619 		IF_AFDATA_WLOCK_ASSERT(ifp);
1620 		lltable_unlink_entry(llt, lle);
1621 	}
1622 
1623 	/* cancel timer */
1624 	if (callout_stop(&lle->lle_timer))
1625 		LLE_REMREF(lle);
1626 
1627 	/* Drop hold queue */
1628 	pkts_dropped = llentry_free(lle);
1629 	arp_stat_add(ARP_STAT_DFRDROPPED, (uint64_t)pkts_dropped);
1630 }
1631 
1632 static int
1633 in_lltable_rtcheck(struct ifnet *ifp, u_int flags, const struct sockaddr *l3addr)
1634 {
1635 	struct rtentry *rt;
1636 	int error = EINVAL;
1637 
1638 	KASSERTMSG(l3addr->sa_family == AF_INET,
1639 	    "sin_family %d", l3addr->sa_family);
1640 
1641 	rt = rtalloc1(l3addr, 0);
1642 	if (rt == NULL)
1643 		return error;
1644 
1645 	/*
1646 	 * If the gateway for an existing host route matches the target L3
1647 	 * address, which is a special route inserted by some implementation
1648 	 * such as MANET, and the interface is of the correct type, then
1649 	 * allow for ARP to proceed.
1650 	 */
1651 	if (rt->rt_flags & RTF_GATEWAY) {
1652 		if (!(rt->rt_flags & RTF_HOST) || !rt->rt_ifp ||
1653 		    rt->rt_ifp->if_type != IFT_ETHER ||
1654 #ifdef __FreeBSD__
1655 		    (rt->rt_ifp->if_flags & (IFF_NOARP | IFF_STATICARP)) != 0 ||
1656 #else
1657 		    (rt->rt_ifp->if_flags & IFF_NOARP) != 0 ||
1658 #endif
1659 		    memcmp(rt->rt_gateway->sa_data, l3addr->sa_data,
1660 		    sizeof(in_addr_t)) != 0) {
1661 			goto error;
1662 		}
1663 	}
1664 
1665 	/*
1666 	 * Make sure that at least the destination address is covered
1667 	 * by the route. This is for handling the case where 2 or more
1668 	 * interfaces have the same prefix. An incoming packet arrives
1669 	 * on one interface and the corresponding outgoing packet leaves
1670 	 * another interface.
1671 	 */
1672 	if (!(rt->rt_flags & RTF_HOST) && rt->rt_ifp != ifp) {
1673 		const char *sa, *mask, *addr, *lim;
1674 		int len;
1675 
1676 		mask = (const char *)rt_mask(rt);
1677 		/*
1678 		 * Just being extra cautious to avoid some custom
1679 		 * code getting into trouble.
1680 		 */
1681 		if (mask == NULL)
1682 			goto error;
1683 
1684 		sa = (const char *)rt_getkey(rt);
1685 		addr = (const char *)l3addr;
1686 		len = ((const struct sockaddr_in *)l3addr)->sin_len;
1687 		lim = addr + len;
1688 
1689 		for ( ; addr < lim; sa++, mask++, addr++) {
1690 			if ((*sa ^ *addr) & *mask) {
1691 #ifdef DIAGNOSTIC
1692 				log(LOG_INFO, "IPv4 address: \"%s\" is not on the network\n",
1693 				    inet_ntoa(((const struct sockaddr_in *)l3addr)->sin_addr));
1694 #endif
1695 				goto error;
1696 			}
1697 		}
1698 	}
1699 
1700 	error = 0;
1701 error:
1702 	return error;
1703 }
1704 
1705 static inline uint32_t
1706 in_lltable_hash_dst(const struct in_addr dst, uint32_t hsize)
1707 {
1708 
1709 	return (IN_LLTBL_HASH(dst.s_addr, hsize));
1710 }
1711 
1712 static uint32_t
1713 in_lltable_hash(const struct llentry *lle, uint32_t hsize)
1714 {
1715 
1716 	return (in_lltable_hash_dst(lle->r_l3addr.addr4, hsize));
1717 }
1718 
1719 static void
1720 in_lltable_fill_sa_entry(const struct llentry *lle, struct sockaddr *sa)
1721 {
1722 	struct sockaddr_in *sin;
1723 
1724 	sin = (struct sockaddr_in *)sa;
1725 	memset(sin, 0, sizeof(*sin));
1726 	sin->sin_family = AF_INET;
1727 	sin->sin_len = sizeof(*sin);
1728 	sin->sin_addr = lle->r_l3addr.addr4;
1729 }
1730 
1731 static inline struct llentry *
1732 in_lltable_find_dst(struct lltable *llt, struct in_addr dst)
1733 {
1734 	struct llentry *lle;
1735 	struct llentries *lleh;
1736 	u_int hashidx;
1737 
1738 	hashidx = in_lltable_hash_dst(dst, llt->llt_hsize);
1739 	lleh = &llt->lle_head[hashidx];
1740 	LIST_FOREACH(lle, lleh, lle_next) {
1741 		if (lle->la_flags & LLE_DELETED)
1742 			continue;
1743 		if (lle->r_l3addr.addr4.s_addr == dst.s_addr)
1744 			break;
1745 	}
1746 
1747 	return (lle);
1748 }
1749 
1750 static int
1751 in_lltable_delete(struct lltable *llt, u_int flags,
1752     const struct sockaddr *l3addr)
1753 {
1754 	const struct sockaddr_in *sin = (const struct sockaddr_in *)l3addr;
1755 	struct ifnet *ifp __diagused = llt->llt_ifp;
1756 	struct llentry *lle;
1757 
1758 	IF_AFDATA_WLOCK_ASSERT(ifp);
1759 	KASSERTMSG(l3addr->sa_family == AF_INET,
1760 	    "sin_family %d", l3addr->sa_family);
1761 
1762 	lle = in_lltable_find_dst(llt, sin->sin_addr);
1763 	if (lle == NULL) {
1764 #ifdef DIAGNOSTIC
1765 		log(LOG_INFO, "interface address is missing from cache = %p  in delete\n", lle);
1766 #endif
1767 		return (ENOENT);
1768 	}
1769 
1770 	if (!(lle->la_flags & LLE_IFADDR) || (flags & LLE_IFADDR)) {
1771 		LLE_WLOCK(lle);
1772 		lle->la_flags |= LLE_DELETED;
1773 #ifdef DIAGNOSTIC
1774 		log(LOG_INFO, "ifaddr cache = %p is deleted\n", lle);
1775 #endif
1776 		if ((lle->la_flags & (LLE_STATIC | LLE_IFADDR)) == LLE_STATIC)
1777 			llentry_free(lle);
1778 		else
1779 			LLE_WUNLOCK(lle);
1780 	}
1781 
1782 	return (0);
1783 }
1784 
1785 static struct llentry *
1786 in_lltable_create(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
1787 {
1788 	const struct sockaddr_in *sin = (const struct sockaddr_in *)l3addr;
1789 	struct ifnet *ifp = llt->llt_ifp;
1790 	struct llentry *lle;
1791 
1792 	IF_AFDATA_WLOCK_ASSERT(ifp);
1793 	KASSERTMSG(l3addr->sa_family == AF_INET,
1794 	    "sin_family %d", l3addr->sa_family);
1795 
1796 	lle = in_lltable_find_dst(llt, sin->sin_addr);
1797 
1798 	if (lle != NULL) {
1799 		LLE_WLOCK(lle);
1800 		return (lle);
1801 	}
1802 
1803 	/* no existing record, we need to create new one */
1804 
1805 	/*
1806 	 * A route that covers the given address must have
1807 	 * been installed 1st because we are doing a resolution,
1808 	 * verify this.
1809 	 */
1810 	if (!(flags & LLE_IFADDR) &&
1811 	    in_lltable_rtcheck(ifp, flags, l3addr) != 0)
1812 		return (NULL);
1813 
1814 	lle = in_lltable_new(sin->sin_addr, flags);
1815 	if (lle == NULL) {
1816 		log(LOG_INFO, "lla_lookup: new lle malloc failed\n");
1817 		return (NULL);
1818 	}
1819 	lle->la_flags = flags;
1820 	if ((flags & LLE_IFADDR) == LLE_IFADDR) {
1821 		memcpy(&lle->ll_addr, CLLADDR(ifp->if_sadl), ifp->if_addrlen);
1822 		lle->la_flags |= (LLE_VALID | LLE_STATIC);
1823 	}
1824 
1825 	lltable_link_entry(llt, lle);
1826 	LLE_WLOCK(lle);
1827 
1828 	return (lle);
1829 }
1830 
1831 /*
1832  * Return NULL if not found or marked for deletion.
1833  * If found return lle read locked.
1834  */
1835 static struct llentry *
1836 in_lltable_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
1837 {
1838 	const struct sockaddr_in *sin = (const struct sockaddr_in *)l3addr;
1839 	struct llentry *lle;
1840 
1841 	IF_AFDATA_LOCK_ASSERT(llt->llt_ifp);
1842 	KASSERTMSG(l3addr->sa_family == AF_INET,
1843 	    "sin_family %d", l3addr->sa_family);
1844 
1845 	lle = in_lltable_find_dst(llt, sin->sin_addr);
1846 
1847 	if (lle == NULL)
1848 		return NULL;
1849 
1850 	if (flags & LLE_EXCLUSIVE)
1851 		LLE_WLOCK(lle);
1852 	else
1853 		LLE_RLOCK(lle);
1854 
1855 	return lle;
1856 }
1857 
1858 #endif /* NETHER > 0 */
1859 
1860 static void
1861 in_sysctl_init(struct sysctllog **clog)
1862 {
1863 	sysctl_createv(clog, 0, NULL, NULL,
1864 		       CTLFLAG_PERMANENT,
1865 		       CTLTYPE_NODE, "inet",
1866 		       SYSCTL_DESCR("PF_INET related settings"),
1867 		       NULL, 0, NULL, 0,
1868 		       CTL_NET, PF_INET, CTL_EOL);
1869 	sysctl_createv(clog, 0, NULL, NULL,
1870 		       CTLFLAG_PERMANENT,
1871 		       CTLTYPE_NODE, "ip",
1872 		       SYSCTL_DESCR("IPv4 related settings"),
1873 		       NULL, 0, NULL, 0,
1874 		       CTL_NET, PF_INET, IPPROTO_IP, CTL_EOL);
1875 
1876 	sysctl_createv(clog, 0, NULL, NULL,
1877 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1878 		       CTLTYPE_INT, "subnetsarelocal",
1879 		       SYSCTL_DESCR("Whether logical subnets are considered "
1880 				    "local"),
1881 		       NULL, 0, &subnetsarelocal, 0,
1882 		       CTL_NET, PF_INET, IPPROTO_IP,
1883 		       IPCTL_SUBNETSARELOCAL, CTL_EOL);
1884 	sysctl_createv(clog, 0, NULL, NULL,
1885 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1886 		       CTLTYPE_INT, "hostzerobroadcast",
1887 		       SYSCTL_DESCR("All zeroes address is broadcast address"),
1888 		       NULL, 0, &hostzeroisbroadcast, 0,
1889 		       CTL_NET, PF_INET, IPPROTO_IP,
1890 		       IPCTL_HOSTZEROBROADCAST, CTL_EOL);
1891 }
1892 
1893 #if NETHER > 0
1894 static struct lltable *
1895 in_lltattach(struct ifnet *ifp)
1896 {
1897 	struct lltable *llt;
1898 
1899 	llt = lltable_allocate_htbl(IN_LLTBL_DEFAULT_HSIZE);
1900 	llt->llt_af = AF_INET;
1901 	llt->llt_ifp = ifp;
1902 
1903 	llt->llt_lookup = in_lltable_lookup;
1904 	llt->llt_create = in_lltable_create;
1905 	llt->llt_delete = in_lltable_delete;
1906 #if 0
1907 	llt->llt_dump_entry = in_lltable_dump_entry;
1908 #endif
1909 	llt->llt_hash = in_lltable_hash;
1910 	llt->llt_fill_sa_entry = in_lltable_fill_sa_entry;
1911 	llt->llt_free_entry = in_lltable_free_entry;
1912 	llt->llt_match_prefix = in_lltable_match_prefix;
1913 	lltable_link(llt);
1914 
1915 	return (llt);
1916 }
1917 #endif /* NETHER > 0 */
1918 
1919 void *
1920 in_domifattach(struct ifnet *ifp)
1921 {
1922 	struct in_ifinfo *ii;
1923 
1924 	ii = kmem_zalloc(sizeof(struct in_ifinfo), KM_SLEEP);
1925 	KASSERT(ii != NULL);
1926 
1927 #if NETHER > 0
1928 	ii->ii_llt = in_lltattach(ifp);
1929 #endif
1930 
1931 #ifdef IPSELSRC
1932 	ii->ii_selsrc = in_selsrc_domifattach(ifp);
1933 	KASSERT(ii->ii_selsrc != NULL);
1934 #endif
1935 
1936 	return ii;
1937 }
1938 
1939 void
1940 in_domifdetach(struct ifnet *ifp, void *aux)
1941 {
1942 	struct in_ifinfo *ii = aux;
1943 
1944 #ifdef IPSELSRC
1945 	in_selsrc_domifdetach(ifp, ii->ii_selsrc);
1946 #endif
1947 #if NETHER > 0
1948 	lltable_free(ii->ii_llt);
1949 #endif
1950 	kmem_free(ii, sizeof(struct in_ifinfo));
1951 }
1952