xref: /netbsd-src/sys/netinet/in.c (revision 212397c69a103ae7e5eafa8731ddfae671d2dee7)
1 /*	$NetBSD: in.c,v 1.163 2015/11/26 01:41:20 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 1.163 2015/11/26 01:41:20 ozaki-r Exp $");
95 
96 #include "arp.h"
97 
98 #ifdef _KERNEL_OPT
99 #include "opt_inet.h"
100 #include "opt_inet_conf.h"
101 #include "opt_mrouting.h"
102 #endif
103 
104 #include <sys/param.h>
105 #include <sys/ioctl.h>
106 #include <sys/errno.h>
107 #include <sys/kernel.h>
108 #include <sys/malloc.h>
109 #include <sys/socket.h>
110 #include <sys/socketvar.h>
111 #include <sys/sysctl.h>
112 #include <sys/systm.h>
113 #include <sys/proc.h>
114 #include <sys/syslog.h>
115 #include <sys/kauth.h>
116 #include <sys/kmem.h>
117 
118 #include <sys/cprng.h>
119 
120 #include <net/if.h>
121 #include <net/route.h>
122 #include <net/pfil.h>
123 
124 #include <net/if_arp.h>
125 #include <net/if_ether.h>
126 #include <net/if_types.h>
127 #include <net/if_llatbl.h>
128 #include <net/if_dl.h>
129 
130 #include <netinet/in_systm.h>
131 #include <netinet/in.h>
132 #include <netinet/in_var.h>
133 #include <netinet/ip.h>
134 #include <netinet/ip_var.h>
135 #include <netinet/in_ifattach.h>
136 #include <netinet/in_pcb.h>
137 #include <netinet/in_selsrc.h>
138 #include <netinet/if_inarp.h>
139 #include <netinet/ip_mroute.h>
140 #include <netinet/igmp_var.h>
141 
142 #ifdef IPSELSRC
143 #include <netinet/in_selsrc.h>
144 #endif
145 
146 static u_int	in_mask2len(struct in_addr *);
147 static void	in_len2mask(struct in_addr *, u_int);
148 static int	in_lifaddr_ioctl(struct socket *, u_long, void *,
149 	struct ifnet *);
150 
151 static int	in_addprefix(struct in_ifaddr *, int);
152 static int	in_scrubprefix(struct in_ifaddr *);
153 static void	in_sysctl_init(struct sysctllog **);
154 
155 #ifndef SUBNETSARELOCAL
156 #define	SUBNETSARELOCAL	1
157 #endif
158 
159 #ifndef HOSTZEROBROADCAST
160 #define HOSTZEROBROADCAST 1
161 #endif
162 
163 /* Note: 61, 127, 251, 509, 1021, 2039 are good. */
164 #ifndef IN_MULTI_HASH_SIZE
165 #define IN_MULTI_HASH_SIZE	509
166 #endif
167 
168 static int			subnetsarelocal = SUBNETSARELOCAL;
169 static int			hostzeroisbroadcast = HOSTZEROBROADCAST;
170 
171 /*
172  * This list is used to keep track of in_multi chains which belong to
173  * deleted interface addresses.  We use in_ifaddr so that a chain head
174  * won't be deallocated until all multicast address record are deleted.
175  */
176 
177 LIST_HEAD(in_multihashhead, in_multi);		/* Type of the hash head */
178 
179 static struct pool		inmulti_pool;
180 static u_int			in_multientries;
181 static struct in_multihashhead *in_multihashtbl;
182 static u_long			in_multihash;
183 static krwlock_t		in_multilock;
184 
185 #define IN_MULTI_HASH(x, ifp) \
186     (in_multihashtbl[(u_long)((x) ^ (ifp->if_index)) % IN_MULTI_HASH_SIZE])
187 
188 struct in_ifaddrhashhead *	in_ifaddrhashtbl;
189 u_long				in_ifaddrhash;
190 struct in_ifaddrhead		in_ifaddrhead;
191 
192 void
193 in_init(void)
194 {
195 	pool_init(&inmulti_pool, sizeof(struct in_multi), 0, 0, 0, "inmltpl",
196 	    NULL, IPL_SOFTNET);
197 	TAILQ_INIT(&in_ifaddrhead);
198 
199 	in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, true,
200 	    &in_ifaddrhash);
201 	in_multihashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, true,
202 	    &in_multihash);
203 	rw_init(&in_multilock);
204 
205 	in_sysctl_init(NULL);
206 }
207 
208 /*
209  * Return 1 if an internet address is for a ``local'' host
210  * (one to which we have a connection).  If subnetsarelocal
211  * is true, this includes other subnets of the local net.
212  * Otherwise, it includes only the directly-connected (sub)nets.
213  */
214 int
215 in_localaddr(struct in_addr in)
216 {
217 	struct in_ifaddr *ia;
218 
219 	if (subnetsarelocal) {
220 		TAILQ_FOREACH(ia, &in_ifaddrhead, ia_list)
221 			if ((in.s_addr & ia->ia_netmask) == ia->ia_net)
222 				return (1);
223 	} else {
224 		TAILQ_FOREACH(ia, &in_ifaddrhead, ia_list)
225 			if ((in.s_addr & ia->ia_subnetmask) == ia->ia_subnet)
226 				return (1);
227 	}
228 	return (0);
229 }
230 
231 /*
232  * Determine whether an IP address is in a reserved set of addresses
233  * that may not be forwarded, or whether datagrams to that destination
234  * may be forwarded.
235  */
236 int
237 in_canforward(struct in_addr in)
238 {
239 	u_int32_t net;
240 
241 	if (IN_EXPERIMENTAL(in.s_addr) || IN_MULTICAST(in.s_addr))
242 		return (0);
243 	if (IN_CLASSA(in.s_addr)) {
244 		net = in.s_addr & IN_CLASSA_NET;
245 		if (net == 0 || net == htonl(IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
246 			return (0);
247 	}
248 	return (1);
249 }
250 
251 /*
252  * Trim a mask in a sockaddr
253  */
254 void
255 in_socktrim(struct sockaddr_in *ap)
256 {
257 	char *cplim = (char *) &ap->sin_addr;
258 	char *cp = (char *) (&ap->sin_addr + 1);
259 
260 	ap->sin_len = 0;
261 	while (--cp >= cplim)
262 		if (*cp) {
263 			(ap)->sin_len = cp - (char *) (ap) + 1;
264 			break;
265 		}
266 }
267 
268 /*
269  *  Routine to take an Internet address and convert into a
270  *  "dotted quad" representation for printing.
271  */
272 const char *
273 in_fmtaddr(struct in_addr addr)
274 {
275 	static char buf[sizeof("123.456.789.123")];
276 
277 	addr.s_addr = ntohl(addr.s_addr);
278 
279 	snprintf(buf, sizeof(buf), "%d.%d.%d.%d",
280 		(addr.s_addr >> 24) & 0xFF,
281 		(addr.s_addr >> 16) & 0xFF,
282 		(addr.s_addr >>  8) & 0xFF,
283 		(addr.s_addr >>  0) & 0xFF);
284 	return buf;
285 }
286 
287 /*
288  * Maintain the "in_maxmtu" variable, which is the largest
289  * mtu for non-local interfaces with AF_INET addresses assigned
290  * to them that are up.
291  */
292 unsigned long in_maxmtu;
293 
294 void
295 in_setmaxmtu(void)
296 {
297 	struct in_ifaddr *ia;
298 	struct ifnet *ifp;
299 	unsigned long maxmtu = 0;
300 
301 	TAILQ_FOREACH(ia, &in_ifaddrhead, ia_list) {
302 		if ((ifp = ia->ia_ifp) == 0)
303 			continue;
304 		if ((ifp->if_flags & (IFF_UP|IFF_LOOPBACK)) != IFF_UP)
305 			continue;
306 		if (ifp->if_mtu > maxmtu)
307 			maxmtu = ifp->if_mtu;
308 	}
309 	if (maxmtu)
310 		in_maxmtu = maxmtu;
311 }
312 
313 static u_int
314 in_mask2len(struct in_addr *mask)
315 {
316 	u_int x, y;
317 	u_char *p;
318 
319 	p = (u_char *)mask;
320 	for (x = 0; x < sizeof(*mask); x++) {
321 		if (p[x] != 0xff)
322 			break;
323 	}
324 	y = 0;
325 	if (x < sizeof(*mask)) {
326 		for (y = 0; y < NBBY; y++) {
327 			if ((p[x] & (0x80 >> y)) == 0)
328 				break;
329 		}
330 	}
331 	return x * NBBY + y;
332 }
333 
334 static void
335 in_len2mask(struct in_addr *mask, u_int len)
336 {
337 	u_int i;
338 	u_char *p;
339 
340 	p = (u_char *)mask;
341 	memset(mask, 0, sizeof(*mask));
342 	for (i = 0; i < len / NBBY; i++)
343 		p[i] = 0xff;
344 	if (len % NBBY)
345 		p[i] = (0xff00 >> (len % NBBY)) & 0xff;
346 }
347 
348 /*
349  * Generic internet control operations (ioctl's).
350  * Ifp is 0 if not an interface-specific ioctl.
351  */
352 /* ARGSUSED */
353 int
354 in_control(struct socket *so, u_long cmd, void *data, struct ifnet *ifp)
355 {
356 	struct ifreq *ifr = (struct ifreq *)data;
357 	struct in_ifaddr *ia = NULL;
358 	struct in_aliasreq *ifra = (struct in_aliasreq *)data;
359 	struct sockaddr_in oldaddr;
360 	int error, hostIsNew, maskIsNew;
361 	int newifaddr = 0;
362 
363 	switch (cmd) {
364 	case SIOCALIFADDR:
365 	case SIOCDLIFADDR:
366 	case SIOCGLIFADDR:
367 		if (ifp == NULL)
368 			return EINVAL;
369 		return in_lifaddr_ioctl(so, cmd, data, ifp);
370 	case SIOCGIFADDRPREF:
371 	case SIOCSIFADDRPREF:
372 		if (ifp == NULL)
373 			return EINVAL;
374 		return ifaddrpref_ioctl(so, cmd, data, ifp);
375 	}
376 
377 	/*
378 	 * Find address for this interface, if it exists.
379 	 */
380 	if (ifp != NULL)
381 		IFP_TO_IA(ifp, ia);
382 
383 	hostIsNew = 1;		/* moved here to appease gcc */
384 	switch (cmd) {
385 	case SIOCAIFADDR:
386 	case SIOCDIFADDR:
387 	case SIOCGIFALIAS:
388 	case SIOCGIFAFLAG_IN:
389 		if (ifra->ifra_addr.sin_family == AF_INET)
390 			LIST_FOREACH(ia,
391 			    &IN_IFADDR_HASH(ifra->ifra_addr.sin_addr.s_addr),
392 			    ia_hash) {
393 				if (ia->ia_ifp == ifp &&
394 				    in_hosteq(ia->ia_addr.sin_addr,
395 				    ifra->ifra_addr.sin_addr))
396 					break;
397 			}
398 		if ((cmd == SIOCDIFADDR ||
399 		    cmd == SIOCGIFALIAS ||
400 		    cmd == SIOCGIFAFLAG_IN) &&
401 		    ia == NULL)
402 			return (EADDRNOTAVAIL);
403 
404 		if (cmd == SIOCDIFADDR &&
405 		    ifra->ifra_addr.sin_family == AF_UNSPEC) {
406 			ifra->ifra_addr.sin_family = AF_INET;
407 		}
408 		/* FALLTHROUGH */
409 	case SIOCSIFADDR:
410 		if (ia == NULL || ia->ia_addr.sin_family != AF_INET)
411 			;
412 		else if (ifra->ifra_addr.sin_len == 0) {
413 			ifra->ifra_addr = ia->ia_addr;
414 			hostIsNew = 0;
415 		} else if (in_hosteq(ia->ia_addr.sin_addr,
416 		           ifra->ifra_addr.sin_addr))
417 			hostIsNew = 0;
418 		/* FALLTHROUGH */
419 	case SIOCSIFDSTADDR:
420 		if (ifra->ifra_addr.sin_family != AF_INET)
421 			return (EAFNOSUPPORT);
422 		/* FALLTHROUGH */
423 	case SIOCSIFNETMASK:
424 		if (ifp == NULL)
425 			panic("in_control");
426 
427 		if (cmd == SIOCGIFALIAS || cmd == SIOCGIFAFLAG_IN)
428 			break;
429 
430 		if (ia == NULL &&
431 		    (cmd == SIOCSIFNETMASK || cmd == SIOCSIFDSTADDR))
432 			return (EADDRNOTAVAIL);
433 
434 		if (kauth_authorize_network(curlwp->l_cred, KAUTH_NETWORK_INTERFACE,
435 		    KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
436 		    NULL) != 0)
437 			return (EPERM);
438 
439 		if (ia == NULL) {
440 			ia = malloc(sizeof(*ia), M_IFADDR, M_WAITOK|M_ZERO);
441 			if (ia == NULL)
442 				return (ENOBUFS);
443 			TAILQ_INSERT_TAIL(&in_ifaddrhead, ia, ia_list);
444 			ifaref(&ia->ia_ifa);
445 			ifa_insert(ifp, &ia->ia_ifa);
446 			ia->ia_ifa.ifa_addr = sintosa(&ia->ia_addr);
447 			ia->ia_ifa.ifa_dstaddr = sintosa(&ia->ia_dstaddr);
448 			ia->ia_ifa.ifa_netmask = sintosa(&ia->ia_sockmask);
449 #ifdef IPSELSRC
450 			ia->ia_ifa.ifa_getifa = in_getifa;
451 #else /* IPSELSRC */
452 			ia->ia_ifa.ifa_getifa = NULL;
453 #endif /* IPSELSRC */
454 			ia->ia_sockmask.sin_len = 8;
455 			ia->ia_sockmask.sin_family = AF_INET;
456 			if (ifp->if_flags & IFF_BROADCAST) {
457 				ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
458 				ia->ia_broadaddr.sin_family = AF_INET;
459 			}
460 			ia->ia_ifp = ifp;
461 			ia->ia_idsalt = cprng_fast32() % 65535;
462 			LIST_INIT(&ia->ia_multiaddrs);
463 			newifaddr = 1;
464 		}
465 		break;
466 
467 	case SIOCSIFBRDADDR:
468 		if (kauth_authorize_network(curlwp->l_cred, KAUTH_NETWORK_INTERFACE,
469 		    KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
470 		    NULL) != 0)
471 			return (EPERM);
472 		/* FALLTHROUGH */
473 
474 	case SIOCGIFADDR:
475 	case SIOCGIFNETMASK:
476 	case SIOCGIFDSTADDR:
477 	case SIOCGIFBRDADDR:
478 		if (ia == NULL)
479 			return (EADDRNOTAVAIL);
480 		break;
481 	}
482 	error = 0;
483 	switch (cmd) {
484 
485 	case SIOCGIFADDR:
486 		ifreq_setaddr(cmd, ifr, sintocsa(&ia->ia_addr));
487 		break;
488 
489 	case SIOCGIFBRDADDR:
490 		if ((ifp->if_flags & IFF_BROADCAST) == 0)
491 			return (EINVAL);
492 		ifreq_setdstaddr(cmd, ifr, sintocsa(&ia->ia_broadaddr));
493 		break;
494 
495 	case SIOCGIFDSTADDR:
496 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
497 			return (EINVAL);
498 		ifreq_setdstaddr(cmd, ifr, sintocsa(&ia->ia_dstaddr));
499 		break;
500 
501 	case SIOCGIFNETMASK:
502 		/*
503 		 * We keep the number of trailing zero bytes the sin_len field
504 		 * of ia_sockmask, so we fix this before we pass it back to
505 		 * userland.
506 		 */
507 		oldaddr = ia->ia_sockmask;
508 		oldaddr.sin_len = sizeof(struct sockaddr_in);
509 		ifreq_setaddr(cmd, ifr, (const void *)&oldaddr);
510 		break;
511 
512 	case SIOCSIFDSTADDR:
513 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
514 			return (EINVAL);
515 		oldaddr = ia->ia_dstaddr;
516 		ia->ia_dstaddr = *satocsin(ifreq_getdstaddr(cmd, ifr));
517 		if ((error = if_addr_init(ifp, &ia->ia_ifa, false)) != 0) {
518 			ia->ia_dstaddr = oldaddr;
519 			return error;
520 		}
521 		if (ia->ia_flags & IFA_ROUTE) {
522 			ia->ia_ifa.ifa_dstaddr = sintosa(&oldaddr);
523 			rtinit(&ia->ia_ifa, RTM_DELETE, RTF_HOST);
524 			ia->ia_ifa.ifa_dstaddr = sintosa(&ia->ia_dstaddr);
525 			rtinit(&ia->ia_ifa, RTM_ADD, RTF_HOST|RTF_UP);
526 		}
527 		break;
528 
529 	case SIOCSIFBRDADDR:
530 		if ((ifp->if_flags & IFF_BROADCAST) == 0)
531 			return EINVAL;
532 		ia->ia_broadaddr = *satocsin(ifreq_getbroadaddr(cmd, ifr));
533 		break;
534 
535 	case SIOCSIFADDR:
536 		error = in_ifinit(ifp, ia, satocsin(ifreq_getaddr(cmd, ifr)),
537 		    1, hostIsNew);
538 		if (error == 0) {
539 			(void)pfil_run_hooks(if_pfil,
540 			    (struct mbuf **)SIOCSIFADDR, ifp, PFIL_IFADDR);
541 		}
542 		break;
543 
544 	case SIOCSIFNETMASK:
545 		in_ifscrub(ifp, ia);
546 		ia->ia_sockmask = *satocsin(ifreq_getaddr(cmd, ifr));
547 		ia->ia_subnetmask = ia->ia_sockmask.sin_addr.s_addr;
548 		error = in_ifinit(ifp, ia, NULL, 0, 0);
549 		break;
550 
551 	case SIOCAIFADDR:
552 		maskIsNew = 0;
553 		if (ifra->ifra_mask.sin_len) {
554 			/* Only scrub if we control the prefix route,
555 			 * otherwise userland gets a bogus message */
556 			if ((ia->ia_flags & IFA_ROUTE))
557 				in_ifscrub(ifp, ia);
558 			ia->ia_sockmask = ifra->ifra_mask;
559 			ia->ia_subnetmask = ia->ia_sockmask.sin_addr.s_addr;
560 			maskIsNew = 1;
561 		}
562 		if ((ifp->if_flags & IFF_POINTOPOINT) &&
563 		    (ifra->ifra_dstaddr.sin_family == AF_INET)) {
564 			/* Only scrub if we control the prefix route,
565 			 * otherwise userland gets a bogus message */
566 			if ((ia->ia_flags & IFA_ROUTE))
567 				in_ifscrub(ifp, ia);
568 			ia->ia_dstaddr = ifra->ifra_dstaddr;
569 			maskIsNew  = 1; /* We lie; but the effect's the same */
570 		}
571 		if (ifra->ifra_addr.sin_family == AF_INET &&
572 		    (hostIsNew || maskIsNew)) {
573 			error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0,
574 			    hostIsNew);
575 		}
576 		if ((ifp->if_flags & IFF_BROADCAST) &&
577 		    (ifra->ifra_broadaddr.sin_family == AF_INET))
578 			ia->ia_broadaddr = ifra->ifra_broadaddr;
579 		if (error == 0)
580 			(void)pfil_run_hooks(if_pfil,
581 			    (struct mbuf **)SIOCAIFADDR, ifp, PFIL_IFADDR);
582 		break;
583 
584 	case SIOCGIFALIAS:
585 		ifra->ifra_mask = ia->ia_sockmask;
586 		if ((ifp->if_flags & IFF_POINTOPOINT) &&
587 		    (ia->ia_dstaddr.sin_family == AF_INET))
588 			ifra->ifra_dstaddr = ia->ia_dstaddr;
589 		else if ((ifp->if_flags & IFF_BROADCAST) &&
590 		    (ia->ia_broadaddr.sin_family == AF_INET))
591 			ifra->ifra_broadaddr = ia->ia_broadaddr;
592 		else
593 			memset(&ifra->ifra_broadaddr, 0,
594 			      sizeof(ifra->ifra_broadaddr));
595 		break;
596 
597 	case SIOCGIFAFLAG_IN:
598 		ifr->ifr_addrflags = ia->ia4_flags;
599 		break;
600 
601 	case SIOCDIFADDR:
602 		in_purgeaddr(&ia->ia_ifa);
603 		(void)pfil_run_hooks(if_pfil, (struct mbuf **)SIOCDIFADDR,
604 		    ifp, PFIL_IFADDR);
605 		break;
606 
607 #ifdef MROUTING
608 	case SIOCGETVIFCNT:
609 	case SIOCGETSGCNT:
610 		error = mrt_ioctl(so, cmd, data);
611 		break;
612 #endif /* MROUTING */
613 
614 	default:
615 		return ENOTTY;
616 	}
617 
618 	if (error != 0 && newifaddr) {
619 		KASSERT(ia != NULL);
620 		in_purgeaddr(&ia->ia_ifa);
621 	}
622 
623 	return error;
624 }
625 
626 /* Add ownaddr as loopback rtentry. */
627 static void
628 in_ifaddlocal(struct ifaddr *ifa)
629 {
630 	struct in_ifaddr *ia;
631 
632 	ia = (struct in_ifaddr *)ifa;
633 	if (ia->ia_addr.sin_addr.s_addr == INADDR_ANY ||
634 	    (ia->ia_ifp->if_flags & IFF_POINTOPOINT &&
635 	    in_hosteq(ia->ia_dstaddr.sin_addr, ia->ia_addr.sin_addr)))
636 	{
637 		rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL);
638 		return;
639 	}
640 
641 	rt_ifa_addlocal(ifa);
642 }
643 
644 /* Rempve loopback entry of ownaddr */
645 static void
646 in_ifremlocal(struct ifaddr *ifa)
647 {
648 	struct in_ifaddr *ia, *p;
649 	struct ifaddr *alt_ifa = NULL;
650 	int ia_count = 0;
651 
652 	ia = (struct in_ifaddr *)ifa;
653 	/* Delete the entry if exactly one ifaddr matches the
654 	 * address, ifa->ifa_addr. */
655 	TAILQ_FOREACH(p, &in_ifaddrhead, ia_list) {
656 		if (!in_hosteq(p->ia_addr.sin_addr, ia->ia_addr.sin_addr))
657 			continue;
658 		if (p->ia_ifp != ia->ia_ifp)
659 			alt_ifa = &p->ia_ifa;
660 		if (++ia_count > 1 && alt_ifa != NULL)
661 			break;
662 	}
663 
664 	if (ia_count == 0)
665 		return;
666 
667 	rt_ifa_remlocal(ifa, ia_count == 1 ? NULL : alt_ifa);
668 }
669 
670 void
671 in_purgeaddr(struct ifaddr *ifa)
672 {
673 	struct ifnet *ifp = ifa->ifa_ifp;
674 	struct in_ifaddr *ia = (void *) ifa;
675 
676 	/* stop DAD processing */
677 	if (ia->ia_dad_stop != NULL)
678 		ia->ia_dad_stop(ifa);
679 
680 	in_ifscrub(ifp, ia);
681 	in_ifremlocal(ifa);
682 	LIST_REMOVE(ia, ia_hash);
683 	ifa_remove(ifp, &ia->ia_ifa);
684 	TAILQ_REMOVE(&in_ifaddrhead, ia, ia_list);
685 	if (ia->ia_allhosts != NULL)
686 		in_delmulti(ia->ia_allhosts);
687 	ifafree(&ia->ia_ifa);
688 	in_setmaxmtu();
689 }
690 
691 void
692 in_purgeif(struct ifnet *ifp)		/* MUST be called at splsoftnet() */
693 {
694 	if_purgeaddrs(ifp, AF_INET, in_purgeaddr);
695 	igmp_purgeif(ifp);		/* manipulates pools */
696 #ifdef MROUTING
697 	ip_mrouter_detach(ifp);
698 #endif
699 }
700 
701 /*
702  * SIOC[GAD]LIFADDR.
703  *	SIOCGLIFADDR: get first address. (???)
704  *	SIOCGLIFADDR with IFLR_PREFIX:
705  *		get first address that matches the specified prefix.
706  *	SIOCALIFADDR: add the specified address.
707  *	SIOCALIFADDR with IFLR_PREFIX:
708  *		EINVAL since we can't deduce hostid part of the address.
709  *	SIOCDLIFADDR: delete the specified address.
710  *	SIOCDLIFADDR with IFLR_PREFIX:
711  *		delete the first address that matches the specified prefix.
712  * return values:
713  *	EINVAL on invalid parameters
714  *	EADDRNOTAVAIL on prefix match failed/specified address not found
715  *	other values may be returned from in_ioctl()
716  */
717 static int
718 in_lifaddr_ioctl(struct socket *so, u_long cmd, void *data,
719     struct ifnet *ifp)
720 {
721 	struct if_laddrreq *iflr = (struct if_laddrreq *)data;
722 	struct ifaddr *ifa;
723 	struct sockaddr *sa;
724 
725 	/* sanity checks */
726 	if (data == NULL || ifp == NULL) {
727 		panic("invalid argument to in_lifaddr_ioctl");
728 		/*NOTRECHED*/
729 	}
730 
731 	switch (cmd) {
732 	case SIOCGLIFADDR:
733 		/* address must be specified on GET with IFLR_PREFIX */
734 		if ((iflr->flags & IFLR_PREFIX) == 0)
735 			break;
736 		/*FALLTHROUGH*/
737 	case SIOCALIFADDR:
738 	case SIOCDLIFADDR:
739 		/* address must be specified on ADD and DELETE */
740 		sa = (struct sockaddr *)&iflr->addr;
741 		if (sa->sa_family != AF_INET)
742 			return EINVAL;
743 		if (sa->sa_len != sizeof(struct sockaddr_in))
744 			return EINVAL;
745 		/* XXX need improvement */
746 		sa = (struct sockaddr *)&iflr->dstaddr;
747 		if (sa->sa_family != AF_UNSPEC && sa->sa_family != AF_INET)
748 			return EINVAL;
749 		if (sa->sa_len != 0 && sa->sa_len != sizeof(struct sockaddr_in))
750 			return EINVAL;
751 		break;
752 	default: /*shouldn't happen*/
753 #if 0
754 		panic("invalid cmd to in_lifaddr_ioctl");
755 		/*NOTREACHED*/
756 #else
757 		return EOPNOTSUPP;
758 #endif
759 	}
760 	if (sizeof(struct in_addr) * NBBY < iflr->prefixlen)
761 		return EINVAL;
762 
763 	switch (cmd) {
764 	case SIOCALIFADDR:
765 	    {
766 		struct in_aliasreq ifra;
767 
768 		if (iflr->flags & IFLR_PREFIX)
769 			return EINVAL;
770 
771 		/* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR). */
772 		memset(&ifra, 0, sizeof(ifra));
773 		memcpy(ifra.ifra_name, iflr->iflr_name,
774 			sizeof(ifra.ifra_name));
775 
776 		memcpy(&ifra.ifra_addr, &iflr->addr,
777 			((struct sockaddr *)&iflr->addr)->sa_len);
778 
779 		if (((struct sockaddr *)&iflr->dstaddr)->sa_family) {	/*XXX*/
780 			memcpy(&ifra.ifra_dstaddr, &iflr->dstaddr,
781 				((struct sockaddr *)&iflr->dstaddr)->sa_len);
782 		}
783 
784 		ifra.ifra_mask.sin_family = AF_INET;
785 		ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
786 		in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);
787 
788 		return in_control(so, SIOCAIFADDR, &ifra, ifp);
789 	    }
790 	case SIOCGLIFADDR:
791 	case SIOCDLIFADDR:
792 	    {
793 		struct in_ifaddr *ia;
794 		struct in_addr mask, candidate, match;
795 		struct sockaddr_in *sin;
796 		int cmp;
797 
798 		memset(&mask, 0, sizeof(mask));
799 		memset(&match, 0, sizeof(match));	/* XXX gcc */
800 		if (iflr->flags & IFLR_PREFIX) {
801 			/* lookup a prefix rather than address. */
802 			in_len2mask(&mask, iflr->prefixlen);
803 
804 			sin = (struct sockaddr_in *)&iflr->addr;
805 			match.s_addr = sin->sin_addr.s_addr;
806 			match.s_addr &= mask.s_addr;
807 
808 			/* if you set extra bits, that's wrong */
809 			if (match.s_addr != sin->sin_addr.s_addr)
810 				return EINVAL;
811 
812 			cmp = 1;
813 		} else {
814 			if (cmd == SIOCGLIFADDR) {
815 				/* on getting an address, take the 1st match */
816 				cmp = 0;	/*XXX*/
817 			} else {
818 				/* on deleting an address, do exact match */
819 				in_len2mask(&mask, 32);
820 				sin = (struct sockaddr_in *)&iflr->addr;
821 				match.s_addr = sin->sin_addr.s_addr;
822 
823 				cmp = 1;
824 			}
825 		}
826 
827 		IFADDR_FOREACH(ifa, ifp) {
828 			if (ifa->ifa_addr->sa_family != AF_INET)
829 				continue;
830 			if (cmp == 0)
831 				break;
832 			candidate.s_addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr;
833 			candidate.s_addr &= mask.s_addr;
834 			if (candidate.s_addr == match.s_addr)
835 				break;
836 		}
837 		if (ifa == NULL)
838 			return EADDRNOTAVAIL;
839 		ia = (struct in_ifaddr *)ifa;
840 
841 		if (cmd == SIOCGLIFADDR) {
842 			/* fill in the if_laddrreq structure */
843 			memcpy(&iflr->addr, &ia->ia_addr, ia->ia_addr.sin_len);
844 
845 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
846 				memcpy(&iflr->dstaddr, &ia->ia_dstaddr,
847 					ia->ia_dstaddr.sin_len);
848 			} else
849 				memset(&iflr->dstaddr, 0, sizeof(iflr->dstaddr));
850 
851 			iflr->prefixlen =
852 				in_mask2len(&ia->ia_sockmask.sin_addr);
853 
854 			iflr->flags = 0;	/*XXX*/
855 
856 			return 0;
857 		} else {
858 			struct in_aliasreq ifra;
859 
860 			/* fill in_aliasreq and do ioctl(SIOCDIFADDR) */
861 			memset(&ifra, 0, sizeof(ifra));
862 			memcpy(ifra.ifra_name, iflr->iflr_name,
863 				sizeof(ifra.ifra_name));
864 
865 			memcpy(&ifra.ifra_addr, &ia->ia_addr,
866 				ia->ia_addr.sin_len);
867 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
868 				memcpy(&ifra.ifra_dstaddr, &ia->ia_dstaddr,
869 					ia->ia_dstaddr.sin_len);
870 			}
871 			memcpy(&ifra.ifra_dstaddr, &ia->ia_sockmask,
872 				ia->ia_sockmask.sin_len);
873 
874 			return in_control(so, SIOCDIFADDR, &ifra, ifp);
875 		}
876 	    }
877 	}
878 
879 	return EOPNOTSUPP;	/*just for safety*/
880 }
881 
882 /*
883  * Delete any existing route for an interface.
884  */
885 void
886 in_ifscrub(struct ifnet *ifp, struct in_ifaddr *ia)
887 {
888 
889 	in_scrubprefix(ia);
890 }
891 
892 /*
893  * Initialize an interface's internet address
894  * and routing table entry.
895  */
896 int
897 in_ifinit(struct ifnet *ifp, struct in_ifaddr *ia,
898     const struct sockaddr_in *sin, int scrub, int hostIsNew)
899 {
900 	u_int32_t i;
901 	struct sockaddr_in oldaddr;
902 	int s = splnet(), flags = RTF_UP, error;
903 
904 	if (sin == NULL)
905 		sin = &ia->ia_addr;
906 
907 	/*
908 	 * Set up new addresses.
909 	 */
910 	oldaddr = ia->ia_addr;
911 	if (ia->ia_addr.sin_family == AF_INET)
912 		LIST_REMOVE(ia, ia_hash);
913 	ia->ia_addr = *sin;
914 	LIST_INSERT_HEAD(&IN_IFADDR_HASH(ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
915 
916 	/* Set IN_IFF flags early for if_addr_init() */
917 	if (hostIsNew && if_do_dad(ifp) && !in_nullhost(ia->ia_addr.sin_addr)) {
918 		if (ifp->if_link_state == LINK_STATE_DOWN)
919 			ia->ia4_flags |= IN_IFF_DETACHED;
920 		else
921 			/* State the intent to try DAD if possible */
922 			ia->ia4_flags |= IN_IFF_TRYTENTATIVE;
923 	}
924 
925 	/*
926 	 * Give the interface a chance to initialize
927 	 * if this is its first address,
928 	 * and to validate the address if necessary.
929 	 */
930 	if ((error = if_addr_init(ifp, &ia->ia_ifa, true)) != 0)
931 		goto bad;
932 	/* Now clear the try tentative flag, it's job is done. */
933 	ia->ia4_flags &= ~IN_IFF_TRYTENTATIVE;
934 	splx(s);
935 
936 	if (scrub) {
937 		ia->ia_ifa.ifa_addr = sintosa(&oldaddr);
938 		in_ifscrub(ifp, ia);
939 		ia->ia_ifa.ifa_addr = sintosa(&ia->ia_addr);
940 	}
941 
942 	/* Add the local route to the address */
943 	in_ifaddlocal(&ia->ia_ifa);
944 
945 	i = ia->ia_addr.sin_addr.s_addr;
946 	if (IN_CLASSA(i))
947 		ia->ia_netmask = IN_CLASSA_NET;
948 	else if (IN_CLASSB(i))
949 		ia->ia_netmask = IN_CLASSB_NET;
950 	else
951 		ia->ia_netmask = IN_CLASSC_NET;
952 	/*
953 	 * The subnet mask usually includes at least the standard network part,
954 	 * but may may be smaller in the case of supernetting.
955 	 * If it is set, we believe it.
956 	 */
957 	if (ia->ia_subnetmask == 0) {
958 		ia->ia_subnetmask = ia->ia_netmask;
959 		ia->ia_sockmask.sin_addr.s_addr = ia->ia_subnetmask;
960 	} else
961 		ia->ia_netmask &= ia->ia_subnetmask;
962 
963 	ia->ia_net = i & ia->ia_netmask;
964 	ia->ia_subnet = i & ia->ia_subnetmask;
965 	in_socktrim(&ia->ia_sockmask);
966 	/* re-calculate the "in_maxmtu" value */
967 	in_setmaxmtu();
968 	/*
969 	 * Add route for the network.
970 	 */
971 	ia->ia_ifa.ifa_metric = ifp->if_metric;
972 	if (ifp->if_flags & IFF_BROADCAST) {
973 		ia->ia_broadaddr.sin_addr.s_addr =
974 			ia->ia_subnet | ~ia->ia_subnetmask;
975 		ia->ia_netbroadcast.s_addr =
976 			ia->ia_net | ~ia->ia_netmask;
977 	} else if (ifp->if_flags & IFF_LOOPBACK) {
978 		ia->ia_dstaddr = ia->ia_addr;
979 		flags |= RTF_HOST;
980 	} else if (ifp->if_flags & IFF_POINTOPOINT) {
981 		if (ia->ia_dstaddr.sin_family != AF_INET)
982 			return (0);
983 		flags |= RTF_HOST;
984 	}
985 	error = in_addprefix(ia, flags);
986 	/*
987 	 * If the interface supports multicast, join the "all hosts"
988 	 * multicast group on that interface.
989 	 */
990 	if ((ifp->if_flags & IFF_MULTICAST) != 0 && ia->ia_allhosts == NULL) {
991 		struct in_addr addr;
992 
993 		addr.s_addr = INADDR_ALLHOSTS_GROUP;
994 		ia->ia_allhosts = in_addmulti(&addr, ifp);
995 	}
996 
997 	if (hostIsNew && if_do_dad(ifp) &&
998 	    !in_nullhost(ia->ia_addr.sin_addr) &&
999 	    ia->ia4_flags & IN_IFF_TENTATIVE)
1000 		ia->ia_dad_start((struct ifaddr *)ia);
1001 
1002 	return (error);
1003 bad:
1004 	splx(s);
1005 	LIST_REMOVE(ia, ia_hash);
1006 	ia->ia_addr = oldaddr;
1007 	if (ia->ia_addr.sin_family == AF_INET)
1008 		LIST_INSERT_HEAD(&IN_IFADDR_HASH(ia->ia_addr.sin_addr.s_addr),
1009 		    ia, ia_hash);
1010 	return (error);
1011 }
1012 
1013 #define rtinitflags(x) \
1014 	((((x)->ia_ifp->if_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) != 0) \
1015 	    ? RTF_HOST : 0)
1016 
1017 /*
1018  * add a route to prefix ("connected route" in cisco terminology).
1019  * does nothing if there's some interface address with the same prefix already.
1020  */
1021 static int
1022 in_addprefix(struct in_ifaddr *target, int flags)
1023 {
1024 	struct in_ifaddr *ia;
1025 	struct in_addr prefix, mask, p;
1026 	int error;
1027 
1028 	if ((flags & RTF_HOST) != 0)
1029 		prefix = target->ia_dstaddr.sin_addr;
1030 	else {
1031 		prefix = target->ia_addr.sin_addr;
1032 		mask = target->ia_sockmask.sin_addr;
1033 		prefix.s_addr &= mask.s_addr;
1034 	}
1035 
1036 	TAILQ_FOREACH(ia, &in_ifaddrhead, ia_list) {
1037 		if (rtinitflags(ia))
1038 			p = ia->ia_dstaddr.sin_addr;
1039 		else {
1040 			p = ia->ia_addr.sin_addr;
1041 			p.s_addr &= ia->ia_sockmask.sin_addr.s_addr;
1042 		}
1043 
1044 		if (prefix.s_addr != p.s_addr)
1045 			continue;
1046 
1047 		/*
1048 		 * if we got a matching prefix route inserted by other
1049 		 * interface address, we don't need to bother
1050 		 *
1051 		 * XXX RADIX_MPATH implications here? -dyoung
1052 		 */
1053 		if (ia->ia_flags & IFA_ROUTE)
1054 			return 0;
1055 	}
1056 
1057 	/*
1058 	 * noone seem to have prefix route.  insert it.
1059 	 */
1060 	error = rtinit(&target->ia_ifa, RTM_ADD, flags);
1061 	if (error == 0)
1062 		target->ia_flags |= IFA_ROUTE;
1063 	else if (error == EEXIST) {
1064 		/*
1065 		 * the fact the route already exists is not an error.
1066 		 */
1067 		error = 0;
1068 	}
1069 	return error;
1070 }
1071 
1072 /*
1073  * remove a route to prefix ("connected route" in cisco terminology).
1074  * re-installs the route by using another interface address, if there's one
1075  * with the same prefix (otherwise we lose the route mistakenly).
1076  */
1077 static int
1078 in_scrubprefix(struct in_ifaddr *target)
1079 {
1080 	struct in_ifaddr *ia;
1081 	struct in_addr prefix, mask, p;
1082 	int error;
1083 
1084 	/* If we don't have IFA_ROUTE we should still inform userland */
1085 	if ((target->ia_flags & IFA_ROUTE) == 0)
1086 		return 0;
1087 
1088 	if (rtinitflags(target))
1089 		prefix = target->ia_dstaddr.sin_addr;
1090 	else {
1091 		prefix = target->ia_addr.sin_addr;
1092 		mask = target->ia_sockmask.sin_addr;
1093 		prefix.s_addr &= mask.s_addr;
1094 	}
1095 
1096 	TAILQ_FOREACH(ia, &in_ifaddrhead, ia_list) {
1097 		if (rtinitflags(ia))
1098 			p = ia->ia_dstaddr.sin_addr;
1099 		else {
1100 			p = ia->ia_addr.sin_addr;
1101 			p.s_addr &= ia->ia_sockmask.sin_addr.s_addr;
1102 		}
1103 
1104 		if (prefix.s_addr != p.s_addr)
1105 			continue;
1106 
1107 		/*
1108 		 * if we got a matching prefix route, move IFA_ROUTE to him
1109 		 */
1110 		if ((ia->ia_flags & IFA_ROUTE) == 0) {
1111 			rtinit(&target->ia_ifa, RTM_DELETE,
1112 			    rtinitflags(target));
1113 			target->ia_flags &= ~IFA_ROUTE;
1114 
1115 			error = rtinit(&ia->ia_ifa, RTM_ADD,
1116 			    rtinitflags(ia) | RTF_UP);
1117 			if (error == 0)
1118 				ia->ia_flags |= IFA_ROUTE;
1119 			return error;
1120 		}
1121 	}
1122 
1123 	/*
1124 	 * noone seem to have prefix route.  remove it.
1125 	 */
1126 	rtinit(&target->ia_ifa, RTM_DELETE, rtinitflags(target));
1127 	target->ia_flags &= ~IFA_ROUTE;
1128 	return 0;
1129 }
1130 
1131 #undef rtinitflags
1132 
1133 /*
1134  * Return 1 if the address might be a local broadcast address.
1135  */
1136 int
1137 in_broadcast(struct in_addr in, struct ifnet *ifp)
1138 {
1139 	struct ifaddr *ifa;
1140 
1141 	if (in.s_addr == INADDR_BROADCAST ||
1142 	    in_nullhost(in))
1143 		return 1;
1144 	if ((ifp->if_flags & IFF_BROADCAST) == 0)
1145 		return 0;
1146 	/*
1147 	 * Look through the list of addresses for a match
1148 	 * with a broadcast address.
1149 	 */
1150 #define ia (ifatoia(ifa))
1151 	IFADDR_FOREACH(ifa, ifp)
1152 		if (ifa->ifa_addr->sa_family == AF_INET &&
1153 		    !in_hosteq(in, ia->ia_addr.sin_addr) &&
1154 		    (in_hosteq(in, ia->ia_broadaddr.sin_addr) ||
1155 		     in_hosteq(in, ia->ia_netbroadcast) ||
1156 		     (hostzeroisbroadcast &&
1157 		      /*
1158 		       * Check for old-style (host 0) broadcast.
1159 		       */
1160 		      (in.s_addr == ia->ia_subnet ||
1161 		       in.s_addr == ia->ia_net))))
1162 			return 1;
1163 	return (0);
1164 #undef ia
1165 }
1166 
1167 /*
1168  * perform DAD when interface becomes IFF_UP.
1169  */
1170 void
1171 in_if_link_up(struct ifnet *ifp)
1172 {
1173 	struct ifaddr *ifa;
1174 	struct in_ifaddr *ia;
1175 
1176 	/* Ensure it's sane to run DAD */
1177 	if (ifp->if_link_state == LINK_STATE_DOWN)
1178 		return;
1179 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
1180 		return;
1181 
1182 	IFADDR_FOREACH(ifa, ifp) {
1183 		if (ifa->ifa_addr->sa_family != AF_INET)
1184 			continue;
1185 		ia = (struct in_ifaddr *)ifa;
1186 
1187 		/* If detached then mark as tentative */
1188 		if (ia->ia4_flags & IN_IFF_DETACHED) {
1189 			ia->ia4_flags &= ~IN_IFF_DETACHED;
1190 			if (if_do_dad(ifp) && ia->ia_dad_start != NULL)
1191 				ia->ia4_flags |= IN_IFF_TENTATIVE;
1192 			else if ((ia->ia4_flags & IN_IFF_TENTATIVE) == 0)
1193 				rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL);
1194 		}
1195 
1196 		if (ia->ia4_flags & IN_IFF_TENTATIVE) {
1197 			/* Clear the duplicated flag as we're starting DAD. */
1198 			ia->ia4_flags &= ~IN_IFF_DUPLICATED;
1199 			ia->ia_dad_start(ifa);
1200 		}
1201 	}
1202 }
1203 
1204 void
1205 in_if_up(struct ifnet *ifp)
1206 {
1207 
1208 	/* interface may not support link state, so bring it up also */
1209 	in_if_link_up(ifp);
1210 }
1211 
1212 /*
1213  * Mark all addresses as detached.
1214  */
1215 void
1216 in_if_link_down(struct ifnet *ifp)
1217 {
1218 	struct ifaddr *ifa;
1219 	struct in_ifaddr *ia;
1220 
1221 	IFADDR_FOREACH(ifa, ifp) {
1222 		if (ifa->ifa_addr->sa_family != AF_INET)
1223 			continue;
1224 		ia = (struct in_ifaddr *)ifa;
1225 
1226 		/* Stop DAD processing */
1227 		if (ia->ia_dad_stop != NULL)
1228 			ia->ia_dad_stop(ifa);
1229 
1230 		/*
1231 		 * Mark the address as detached.
1232 		 */
1233 		if (!(ia->ia4_flags & IN_IFF_DETACHED)) {
1234 			ia->ia4_flags |= IN_IFF_DETACHED;
1235 			ia->ia4_flags &=
1236 			    ~(IN_IFF_TENTATIVE | IN_IFF_DUPLICATED);
1237 			rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL);
1238 		}
1239 	}
1240 }
1241 
1242 void
1243 in_if_down(struct ifnet *ifp)
1244 {
1245 
1246 	in_if_link_down(ifp);
1247 }
1248 
1249 void
1250 in_if_link_state_change(struct ifnet *ifp, int link_state)
1251 {
1252 
1253 	switch (link_state) {
1254 	case LINK_STATE_DOWN:
1255 		in_if_link_down(ifp);
1256 		break;
1257 	case LINK_STATE_UP:
1258 		in_if_link_up(ifp);
1259 		break;
1260 	}
1261 }
1262 
1263 /*
1264  * in_lookup_multi: look up the in_multi record for a given IP
1265  * multicast address on a given interface.  If no matching record is
1266  * found, return NULL.
1267  */
1268 struct in_multi *
1269 in_lookup_multi(struct in_addr addr, ifnet_t *ifp)
1270 {
1271 	struct in_multi *inm;
1272 
1273 	KASSERT(rw_lock_held(&in_multilock));
1274 
1275 	LIST_FOREACH(inm, &IN_MULTI_HASH(addr.s_addr, ifp), inm_list) {
1276 		if (in_hosteq(inm->inm_addr, addr) && inm->inm_ifp == ifp)
1277 			break;
1278 	}
1279 	return inm;
1280 }
1281 
1282 /*
1283  * in_multi_group: check whether the address belongs to an IP multicast
1284  * group we are joined on this interface.  Returns true or false.
1285  */
1286 bool
1287 in_multi_group(struct in_addr addr, ifnet_t *ifp, int flags)
1288 {
1289 	bool ingroup;
1290 
1291 	if (__predict_true(flags & IP_IGMP_MCAST) == 0) {
1292 		rw_enter(&in_multilock, RW_READER);
1293 		ingroup = in_lookup_multi(addr, ifp) != NULL;
1294 		rw_exit(&in_multilock);
1295 	} else {
1296 		/* XXX Recursive call from ip_output(). */
1297 		KASSERT(rw_lock_held(&in_multilock));
1298 		ingroup = in_lookup_multi(addr, ifp) != NULL;
1299 	}
1300 	return ingroup;
1301 }
1302 
1303 /*
1304  * Add an address to the list of IP multicast addresses for a given interface.
1305  */
1306 struct in_multi *
1307 in_addmulti(struct in_addr *ap, ifnet_t *ifp)
1308 {
1309 	struct sockaddr_in sin;
1310 	struct in_multi *inm;
1311 
1312 	/*
1313 	 * See if address already in list.
1314 	 */
1315 	rw_enter(&in_multilock, RW_WRITER);
1316 	inm = in_lookup_multi(*ap, ifp);
1317 	if (inm != NULL) {
1318 		/*
1319 		 * Found it; just increment the reference count.
1320 		 */
1321 		inm->inm_refcount++;
1322 		rw_exit(&in_multilock);
1323 		return inm;
1324 	}
1325 
1326 	/*
1327 	 * New address; allocate a new multicast record.
1328 	 */
1329 	inm = pool_get(&inmulti_pool, PR_NOWAIT);
1330 	if (inm == NULL) {
1331 		rw_exit(&in_multilock);
1332 		return NULL;
1333 	}
1334 	inm->inm_addr = *ap;
1335 	inm->inm_ifp = ifp;
1336 	inm->inm_refcount = 1;
1337 
1338 	/*
1339 	 * Ask the network driver to update its multicast reception
1340 	 * filter appropriately for the new address.
1341 	 */
1342 	sockaddr_in_init(&sin, ap, 0);
1343 	if (if_mcast_op(ifp, SIOCADDMULTI, sintosa(&sin)) != 0) {
1344 		rw_exit(&in_multilock);
1345 		pool_put(&inmulti_pool, inm);
1346 		return NULL;
1347 	}
1348 
1349 	/*
1350 	 * Let IGMP know that we have joined a new IP multicast group.
1351 	 */
1352 	if (igmp_joingroup(inm) != 0) {
1353 		rw_exit(&in_multilock);
1354 		pool_put(&inmulti_pool, inm);
1355 		return NULL;
1356 	}
1357 	LIST_INSERT_HEAD(
1358 	    &IN_MULTI_HASH(inm->inm_addr.s_addr, ifp),
1359 	    inm, inm_list);
1360 	in_multientries++;
1361 	rw_exit(&in_multilock);
1362 
1363 	return inm;
1364 }
1365 
1366 /*
1367  * Delete a multicast address record.
1368  */
1369 void
1370 in_delmulti(struct in_multi *inm)
1371 {
1372 	struct sockaddr_in sin;
1373 
1374 	rw_enter(&in_multilock, RW_WRITER);
1375 	if (--inm->inm_refcount > 0) {
1376 		rw_exit(&in_multilock);
1377 		return;
1378 	}
1379 
1380 	/*
1381 	 * No remaining claims to this record; let IGMP know that
1382 	 * we are leaving the multicast group.
1383 	 */
1384 	igmp_leavegroup(inm);
1385 
1386 	/*
1387 	 * Notify the network driver to update its multicast reception
1388 	 * filter.
1389 	 */
1390 	sockaddr_in_init(&sin, &inm->inm_addr, 0);
1391 	if_mcast_op(inm->inm_ifp, SIOCDELMULTI, sintosa(&sin));
1392 
1393 	/*
1394 	 * Unlink from list.
1395 	 */
1396 	LIST_REMOVE(inm, inm_list);
1397 	in_multientries--;
1398 	rw_exit(&in_multilock);
1399 
1400 	pool_put(&inmulti_pool, inm);
1401 }
1402 
1403 /*
1404  * in_next_multi: step through all of the in_multi records, one at a time.
1405  * The current position is remembered in "step", which the caller must
1406  * provide.  in_first_multi(), below, must be called to initialize "step"
1407  * and get the first record.  Both macros return a NULL "inm" when there
1408  * are no remaining records.
1409  */
1410 struct in_multi *
1411 in_next_multi(struct in_multistep *step)
1412 {
1413 	struct in_multi *inm;
1414 
1415 	KASSERT(rw_lock_held(&in_multilock));
1416 
1417 	while (step->i_inm == NULL && step->i_n < IN_MULTI_HASH_SIZE) {
1418 		step->i_inm = LIST_FIRST(&in_multihashtbl[++step->i_n]);
1419 	}
1420 	if ((inm = step->i_inm) != NULL) {
1421 		step->i_inm = LIST_NEXT(inm, inm_list);
1422 	}
1423 	return inm;
1424 }
1425 
1426 struct in_multi *
1427 in_first_multi(struct in_multistep *step)
1428 {
1429 	KASSERT(rw_lock_held(&in_multilock));
1430 
1431 	step->i_n = 0;
1432 	step->i_inm = LIST_FIRST(&in_multihashtbl[0]);
1433 	return in_next_multi(step);
1434 }
1435 
1436 void
1437 in_multi_lock(int op)
1438 {
1439 	rw_enter(&in_multilock, op);
1440 }
1441 
1442 void
1443 in_multi_unlock(void)
1444 {
1445 	rw_exit(&in_multilock);
1446 }
1447 
1448 int
1449 in_multi_lock_held(void)
1450 {
1451 	return rw_lock_held(&in_multilock);
1452 }
1453 
1454 struct sockaddr_in *
1455 in_selectsrc(struct sockaddr_in *sin, struct route *ro,
1456     int soopts, struct ip_moptions *mopts, int *errorp)
1457 {
1458 	struct rtentry *rt = NULL;
1459 	struct in_ifaddr *ia = NULL;
1460 
1461 	/*
1462          * If route is known or can be allocated now, take the
1463          * source address from the interface.  Otherwise, punt.
1464 	 */
1465 	if ((soopts & SO_DONTROUTE) != 0)
1466 		rtcache_free(ro);
1467 	else {
1468 		union {
1469 			struct sockaddr		dst;
1470 			struct sockaddr_in	dst4;
1471 		} u;
1472 
1473 		sockaddr_in_init(&u.dst4, &sin->sin_addr, 0);
1474 		rt = rtcache_lookup(ro, &u.dst);
1475 	}
1476 	/*
1477 	 * If we found a route, use the address
1478 	 * corresponding to the outgoing interface
1479 	 * unless it is the loopback (in case a route
1480 	 * to our address on another net goes to loopback).
1481 	 *
1482 	 * XXX Is this still true?  Do we care?
1483 	 */
1484 	if (rt != NULL && (rt->rt_ifp->if_flags & IFF_LOOPBACK) == 0)
1485 		ia = ifatoia(rt->rt_ifa);
1486 	if (ia == NULL) {
1487 		u_int16_t fport = sin->sin_port;
1488 
1489 		sin->sin_port = 0;
1490 		ia = ifatoia(ifa_ifwithladdr(sintosa(sin)));
1491 		sin->sin_port = fport;
1492 		if (ia == NULL) {
1493 			/* Find 1st non-loopback AF_INET address */
1494 			TAILQ_FOREACH(ia, &in_ifaddrhead, ia_list) {
1495 				if (!(ia->ia_ifp->if_flags & IFF_LOOPBACK))
1496 					break;
1497 			}
1498 		}
1499 		if (ia == NULL) {
1500 			*errorp = EADDRNOTAVAIL;
1501 			return NULL;
1502 		}
1503 	}
1504 	/*
1505 	 * If the destination address is multicast and an outgoing
1506 	 * interface has been set as a multicast option, use the
1507 	 * address of that interface as our source address.
1508 	 */
1509 	if (IN_MULTICAST(sin->sin_addr.s_addr) && mopts != NULL) {
1510 		struct ip_moptions *imo;
1511 		struct ifnet *ifp;
1512 
1513 		imo = mopts;
1514 		if (imo->imo_multicast_ifp != NULL) {
1515 			ifp = imo->imo_multicast_ifp;
1516 			IFP_TO_IA(ifp, ia);		/* XXX */
1517 			if (ia == 0 || ia->ia4_flags & IN_IFF_NOTREADY) {
1518 				*errorp = EADDRNOTAVAIL;
1519 				return NULL;
1520 			}
1521 		}
1522 	}
1523 	if (ia->ia_ifa.ifa_getifa != NULL) {
1524 		ia = ifatoia((*ia->ia_ifa.ifa_getifa)(&ia->ia_ifa,
1525 		                                      sintosa(sin)));
1526 		if (ia == NULL) {
1527 			*errorp = EADDRNOTAVAIL;
1528 			return NULL;
1529 		}
1530 	}
1531 #ifdef GETIFA_DEBUG
1532 	else
1533 		printf("%s: missing ifa_getifa\n", __func__);
1534 #endif
1535 	return satosin(&ia->ia_addr);
1536 }
1537 
1538 #if NARP > 0
1539 
1540 struct in_llentry {
1541 	struct llentry		base;
1542 };
1543 
1544 #define	IN_LLTBL_DEFAULT_HSIZE	32
1545 #define	IN_LLTBL_HASH(k, h) \
1546 	(((((((k >> 8) ^ k) >> 8) ^ k) >> 8) ^ k) & ((h) - 1))
1547 
1548 /*
1549  * Do actual deallocation of @lle.
1550  * Called by LLE_FREE_LOCKED when number of references
1551  * drops to zero.
1552  */
1553 static void
1554 in_lltable_destroy_lle(struct llentry *lle)
1555 {
1556 
1557 	LLE_WUNLOCK(lle);
1558 	LLE_LOCK_DESTROY(lle);
1559 	kmem_intr_free(lle, sizeof(*lle));
1560 }
1561 
1562 static struct llentry *
1563 in_lltable_new(struct in_addr addr4, u_int flags)
1564 {
1565 	struct in_llentry *lle;
1566 
1567 	lle = kmem_intr_zalloc(sizeof(*lle), KM_NOSLEEP);
1568 	if (lle == NULL)		/* NB: caller generates msg */
1569 		return NULL;
1570 
1571 	/*
1572 	 * For IPv4 this will trigger "arpresolve" to generate
1573 	 * an ARP request.
1574 	 */
1575 	lle->base.la_expire = time_uptime; /* mark expired */
1576 	lle->base.r_l3addr.addr4 = addr4;
1577 	lle->base.lle_refcnt = 1;
1578 	lle->base.lle_free = in_lltable_destroy_lle;
1579 	LLE_LOCK_INIT(&lle->base);
1580 	callout_init(&lle->base.la_timer, CALLOUT_MPSAFE);
1581 
1582 	return (&lle->base);
1583 }
1584 
1585 #define IN_ARE_MASKED_ADDR_EQUAL(d, a, m)	(			\
1586 	    (((ntohl((d).s_addr) ^ (a)->sin_addr.s_addr) & (m)->sin_addr.s_addr)) == 0 )
1587 
1588 static int
1589 in_lltable_match_prefix(const struct sockaddr *prefix,
1590     const struct sockaddr *mask, u_int flags, struct llentry *lle)
1591 {
1592 	const struct sockaddr_in *pfx = (const struct sockaddr_in *)prefix;
1593 	const struct sockaddr_in *msk = (const struct sockaddr_in *)mask;
1594 
1595 	/*
1596 	 * (flags & LLE_STATIC) means deleting all entries
1597 	 * including static ARP entries.
1598 	 */
1599 	if (IN_ARE_MASKED_ADDR_EQUAL(lle->r_l3addr.addr4, pfx, msk) &&
1600 	    ((flags & LLE_STATIC) || !(lle->la_flags & LLE_STATIC)))
1601 		return (1);
1602 
1603 	return (0);
1604 }
1605 
1606 static void
1607 in_lltable_free_entry(struct lltable *llt, struct llentry *lle)
1608 {
1609 	struct ifnet *ifp __diagused;
1610 	size_t pkts_dropped;
1611 
1612 	LLE_WLOCK_ASSERT(lle);
1613 	KASSERT(llt != NULL);
1614 
1615 	/* Unlink entry from table if not already */
1616 	if ((lle->la_flags & LLE_LINKED) != 0) {
1617 		ifp = llt->llt_ifp;
1618 		IF_AFDATA_WLOCK_ASSERT(ifp);
1619 		lltable_unlink_entry(llt, lle);
1620 	}
1621 
1622 	/* cancel timer */
1623 	if (callout_stop(&lle->lle_timer))
1624 		LLE_REMREF(lle);
1625 
1626 	/* Drop hold queue */
1627 	pkts_dropped = llentry_free(lle);
1628 	arp_stat_add(ARP_STAT_DFRDROPPED, (uint64_t)pkts_dropped);
1629 }
1630 
1631 static int
1632 in_lltable_rtcheck(struct ifnet *ifp, u_int flags, const struct sockaddr *l3addr)
1633 {
1634 	struct rtentry *rt;
1635 	int error = EINVAL;
1636 
1637 	KASSERTMSG(l3addr->sa_family == AF_INET,
1638 	    "sin_family %d", l3addr->sa_family);
1639 
1640 	rt = rtalloc1(l3addr, 0);
1641 	if (rt == NULL)
1642 		return error;
1643 
1644 	/*
1645 	 * If the gateway for an existing host route matches the target L3
1646 	 * address, which is a special route inserted by some implementation
1647 	 * such as MANET, and the interface is of the correct type, then
1648 	 * allow for ARP to proceed.
1649 	 */
1650 	if (rt->rt_flags & RTF_GATEWAY) {
1651 		if (!(rt->rt_flags & RTF_HOST) || !rt->rt_ifp ||
1652 		    rt->rt_ifp->if_type != IFT_ETHER ||
1653 #ifdef __FreeBSD__
1654 		    (rt->rt_ifp->if_flags & (IFF_NOARP | IFF_STATICARP)) != 0 ||
1655 #else
1656 		    (rt->rt_ifp->if_flags & IFF_NOARP) != 0 ||
1657 #endif
1658 		    memcmp(rt->rt_gateway->sa_data, l3addr->sa_data,
1659 		    sizeof(in_addr_t)) != 0) {
1660 			goto error;
1661 		}
1662 	}
1663 
1664 	/*
1665 	 * Make sure that at least the destination address is covered
1666 	 * by the route. This is for handling the case where 2 or more
1667 	 * interfaces have the same prefix. An incoming packet arrives
1668 	 * on one interface and the corresponding outgoing packet leaves
1669 	 * another interface.
1670 	 */
1671 	if (!(rt->rt_flags & RTF_HOST) && rt->rt_ifp != ifp) {
1672 		const char *sa, *mask, *addr, *lim;
1673 		int len;
1674 
1675 		mask = (const char *)rt_mask(rt);
1676 		/*
1677 		 * Just being extra cautious to avoid some custom
1678 		 * code getting into trouble.
1679 		 */
1680 		if (mask == NULL)
1681 			goto error;
1682 
1683 		sa = (const char *)rt_getkey(rt);
1684 		addr = (const char *)l3addr;
1685 		len = ((const struct sockaddr_in *)l3addr)->sin_len;
1686 		lim = addr + len;
1687 
1688 		for ( ; addr < lim; sa++, mask++, addr++) {
1689 			if ((*sa ^ *addr) & *mask) {
1690 #ifdef DIAGNOSTIC
1691 				log(LOG_INFO, "IPv4 address: \"%s\" is not on the network\n",
1692 				    inet_ntoa(((const struct sockaddr_in *)l3addr)->sin_addr));
1693 #endif
1694 				goto error;
1695 			}
1696 		}
1697 	}
1698 
1699 	error = 0;
1700 error:
1701 	rtfree(rt);
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 /* NARP > 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 NARP > 0
1894 
1895 static struct lltable *
1896 in_lltattach(struct ifnet *ifp)
1897 {
1898 	struct lltable *llt;
1899 
1900 	llt = lltable_allocate_htbl(IN_LLTBL_DEFAULT_HSIZE);
1901 	llt->llt_af = AF_INET;
1902 	llt->llt_ifp = ifp;
1903 
1904 	llt->llt_lookup = in_lltable_lookup;
1905 	llt->llt_create = in_lltable_create;
1906 	llt->llt_delete = in_lltable_delete;
1907 #if 0
1908 	llt->llt_dump_entry = in_lltable_dump_entry;
1909 #endif
1910 	llt->llt_hash = in_lltable_hash;
1911 	llt->llt_fill_sa_entry = in_lltable_fill_sa_entry;
1912 	llt->llt_free_entry = in_lltable_free_entry;
1913 	llt->llt_match_prefix = in_lltable_match_prefix;
1914 	lltable_link(llt);
1915 
1916 	return (llt);
1917 }
1918 
1919 #endif /* NARP > 0 */
1920 
1921 void *
1922 in_domifattach(struct ifnet *ifp)
1923 {
1924 	struct in_ifinfo *ii;
1925 
1926 	ii = kmem_zalloc(sizeof(struct in_ifinfo), KM_SLEEP);
1927 	KASSERT(ii != NULL);
1928 
1929 #if NARP > 0
1930 	ii->ii_llt = in_lltattach(ifp);
1931 #endif
1932 
1933 #ifdef IPSELSRC
1934 	ii->ii_selsrc = in_selsrc_domifattach(ifp);
1935 	KASSERT(ii->ii_selsrc != NULL);
1936 #endif
1937 
1938 	return ii;
1939 }
1940 
1941 void
1942 in_domifdetach(struct ifnet *ifp, void *aux)
1943 {
1944 	struct in_ifinfo *ii = aux;
1945 
1946 #ifdef IPSELSRC
1947 	in_selsrc_domifdetach(ifp, ii->ii_selsrc);
1948 #endif
1949 #if NARP > 0
1950 	lltable_free(ii->ii_llt);
1951 #endif
1952 	kmem_free(ii, sizeof(struct in_ifinfo));
1953 }
1954