xref: /dflybsd-src/sys/netinet/in.c (revision b5d16701e255c342d21e69a6c80b8711c028dc65)
1 /*
2  * Copyright (c) 1982, 1986, 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)in.c	8.4 (Berkeley) 1/9/95
34  * $FreeBSD: src/sys/netinet/in.c,v 1.44.2.14 2002/11/08 00:45:50 suz Exp $
35  * $DragonFly: src/sys/netinet/in.c,v 1.41 2008/08/17 05:20:10 sephe Exp $
36  */
37 
38 #include "opt_bootp.h"
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/sockio.h>
43 #include <sys/malloc.h>
44 #include <sys/proc.h>
45 #include <sys/priv.h>
46 #include <sys/msgport.h>
47 #include <sys/socket.h>
48 
49 #include <sys/kernel.h>
50 #include <sys/sysctl.h>
51 #include <sys/thread2.h>
52 
53 #include <net/if.h>
54 #include <net/if_types.h>
55 #include <net/route.h>
56 #include <net/netmsg2.h>
57 
58 #include <netinet/in.h>
59 #include <netinet/in_var.h>
60 #include <netinet/in_pcb.h>
61 
62 #include <netinet/igmp_var.h>
63 
64 MALLOC_DEFINE(M_IPMADDR, "in_multi", "internet multicast address");
65 
66 static int in_mask2len (struct in_addr *);
67 static void in_len2mask (struct in_addr *, int);
68 static int in_lifaddr_ioctl (struct socket *, u_long, caddr_t,
69 	struct ifnet *, struct thread *);
70 
71 static void	in_socktrim (struct sockaddr_in *);
72 static int	in_ifinit(struct ifnet *, struct in_ifaddr *,
73 		    const struct sockaddr_in *, int);
74 
75 static int	in_control_internal(u_long, caddr_t, struct ifnet *,
76 		    struct thread *);
77 
78 static int	in_addprefix(struct in_ifaddr *, int);
79 static void	in_scrubprefix(struct in_ifaddr *);
80 
81 static int subnetsarelocal = 0;
82 SYSCTL_INT(_net_inet_ip, OID_AUTO, subnets_are_local, CTLFLAG_RW,
83     &subnetsarelocal, 0,
84     "Count all internet addresses of subnets of the local net as local");
85 
86 struct in_multihead in_multihead; /* XXX BSS initialization */
87 
88 extern struct inpcbinfo ripcbinfo;
89 extern struct inpcbinfo udbinfo;
90 
91 /*
92  * Return 1 if an internet address is for a ``local'' host
93  * (one to which we have a connection).  If subnetsarelocal
94  * is true, this includes other subnets of the local net.
95  * Otherwise, it includes only the directly-connected (sub)nets.
96  */
97 int
98 in_localaddr(struct in_addr in)
99 {
100 	u_long i = ntohl(in.s_addr);
101 	struct in_ifaddr_container *iac;
102 	struct in_ifaddr *ia;
103 
104 	if (subnetsarelocal) {
105 		TAILQ_FOREACH(iac, &in_ifaddrheads[mycpuid], ia_link) {
106 			ia = iac->ia;
107 
108 			if ((i & ia->ia_netmask) == ia->ia_net)
109 				return (1);
110 		}
111 	} else {
112 		TAILQ_FOREACH(iac, &in_ifaddrheads[mycpuid], ia_link) {
113 			ia = iac->ia;
114 
115 			if ((i & ia->ia_subnetmask) == ia->ia_subnet)
116 				return (1);
117 		}
118 	}
119 	return (0);
120 }
121 
122 /*
123  * Determine whether an IP address is in a reserved set of addresses
124  * that may not be forwarded, or whether datagrams to that destination
125  * may be forwarded.
126  */
127 int
128 in_canforward(struct in_addr in)
129 {
130 	u_long i = ntohl(in.s_addr);
131 	u_long net;
132 
133 	if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i))
134 		return (0);
135 	if (IN_CLASSA(i)) {
136 		net = i & IN_CLASSA_NET;
137 		if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
138 			return (0);
139 	}
140 	return (1);
141 }
142 
143 /*
144  * Trim a mask in a sockaddr
145  */
146 static void
147 in_socktrim(struct sockaddr_in *ap)
148 {
149     char *cplim = (char *) &ap->sin_addr;
150     char *cp = (char *) (&ap->sin_addr + 1);
151 
152     ap->sin_len = 0;
153     while (--cp >= cplim)
154 	if (*cp) {
155 	    (ap)->sin_len = cp - (char *) (ap) + 1;
156 	    break;
157 	}
158 }
159 
160 static int
161 in_mask2len(struct in_addr *mask)
162 {
163 	int x, y;
164 	u_char *p;
165 
166 	p = (u_char *)mask;
167 	for (x = 0; x < sizeof *mask; x++) {
168 		if (p[x] != 0xff)
169 			break;
170 	}
171 	y = 0;
172 	if (x < sizeof *mask) {
173 		for (y = 0; y < 8; y++) {
174 			if ((p[x] & (0x80 >> y)) == 0)
175 				break;
176 		}
177 	}
178 	return x * 8 + y;
179 }
180 
181 static void
182 in_len2mask(struct in_addr *mask, int len)
183 {
184 	int i;
185 	u_char *p;
186 
187 	p = (u_char *)mask;
188 	bzero(mask, sizeof *mask);
189 	for (i = 0; i < len / 8; i++)
190 		p[i] = 0xff;
191 	if (len % 8)
192 		p[i] = (0xff00 >> (len % 8)) & 0xff;
193 }
194 
195 static int in_interfaces;	/* number of external internet interfaces */
196 
197 void
198 in_control_dispatch(netmsg_t msg)
199 {
200 	int error;
201 
202 	error = in_control_internal(msg->control.nm_cmd,
203 				    msg->control.nm_data,
204 				    msg->control.nm_ifp,
205 				    msg->control.nm_td);
206 	lwkt_replymsg(&msg->lmsg, error);
207 }
208 
209 /*
210  * Generic internet control operations (ioctl's).
211  * Ifp is 0 if not an interface-specific ioctl.
212  *
213  * NOTE! td might be NULL.
214  */
215 /* ARGSUSED */
216 int
217 in_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp,
218 	   struct thread *td)
219 {
220 	struct netmsg_pru_control msg;
221 	int error;
222 
223 	switch (cmd) {
224 	case SIOCALIFADDR:
225 	case SIOCDLIFADDR:
226 		if (td && (error = priv_check(td, PRIV_ROOT)) != 0)
227 			return error;
228 		/* FALLTHROUGH */
229 	case SIOCGLIFADDR:
230 		if (!ifp)
231 			return EINVAL;
232 		return in_lifaddr_ioctl(so, cmd, data, ifp, td);
233 	}
234 
235 	KASSERT(cmd != SIOCALIFADDR && cmd != SIOCDLIFADDR,
236 		("recursive SIOC%cLIFADDR!\n",
237 		 cmd == SIOCDLIFADDR ? 'D' : 'A'));
238 
239 	/*
240 	 * IFADDR alterations are serialized by netisr0
241 	 */
242 	switch (cmd) {
243 	case SIOCSIFDSTADDR:
244 	case SIOCSIFBRDADDR:
245 	case SIOCSIFADDR:
246 	case SIOCSIFNETMASK:
247 	case SIOCAIFADDR:
248 	case SIOCDIFADDR:
249 		netmsg_init(&msg.base, NULL, &curthread->td_msgport,
250 			    0, in_control_dispatch);
251 		msg.nm_cmd = cmd;
252 		msg.nm_data = data;
253 		msg.nm_ifp = ifp;
254 		msg.nm_td = td;
255 		lwkt_domsg(cpu_portfn(0), &msg.base.lmsg, 0);
256 		error = msg.base.lmsg.ms_error;
257 		break;
258 	default:
259 		error = in_control_internal(cmd, data, ifp, td);
260 		break;
261 	}
262 	return error;
263 }
264 
265 static void
266 in_ialink_dispatch(netmsg_t msg)
267 {
268 	struct in_ifaddr *ia = msg->lmsg.u.ms_resultp;
269 	struct ifaddr_container *ifac;
270 	struct in_ifaddr_container *iac;
271 	int cpu = mycpuid;
272 
273 	crit_enter();
274 
275 	ifac = &ia->ia_ifa.ifa_containers[cpu];
276 	ASSERT_IFAC_VALID(ifac);
277 	KASSERT((ifac->ifa_listmask & IFA_LIST_IN_IFADDRHEAD) == 0,
278 		("ia is on in_ifaddrheads\n"));
279 
280 	ifac->ifa_listmask |= IFA_LIST_IN_IFADDRHEAD;
281 	iac = &ifac->ifa_proto_u.u_in_ifac;
282 	TAILQ_INSERT_TAIL(&in_ifaddrheads[cpu], iac, ia_link);
283 
284 	crit_exit();
285 
286 	ifa_forwardmsg(&msg->lmsg, cpu + 1);
287 }
288 
289 static void
290 in_iaunlink_dispatch(netmsg_t msg)
291 {
292 	struct in_ifaddr *ia = msg->lmsg.u.ms_resultp;
293 	struct ifaddr_container *ifac;
294 	struct in_ifaddr_container *iac;
295 	int cpu = mycpuid;
296 
297 	crit_enter();
298 
299 	ifac = &ia->ia_ifa.ifa_containers[cpu];
300 	ASSERT_IFAC_VALID(ifac);
301 	KASSERT(ifac->ifa_listmask & IFA_LIST_IN_IFADDRHEAD,
302 		("ia is not on in_ifaddrheads\n"));
303 
304 	iac = &ifac->ifa_proto_u.u_in_ifac;
305 	TAILQ_REMOVE(&in_ifaddrheads[cpu], iac, ia_link);
306 	ifac->ifa_listmask &= ~IFA_LIST_IN_IFADDRHEAD;
307 
308 	crit_exit();
309 
310 	ifa_forwardmsg(&msg->lmsg, cpu + 1);
311 }
312 
313 static void
314 in_iahashins_dispatch(netmsg_t msg)
315 {
316 	struct in_ifaddr *ia = msg->lmsg.u.ms_resultp;
317 	struct ifaddr_container *ifac;
318 	struct in_ifaddr_container *iac;
319 	int cpu = mycpuid;
320 
321 	crit_enter();
322 
323 	ifac = &ia->ia_ifa.ifa_containers[cpu];
324 	ASSERT_IFAC_VALID(ifac);
325 	KASSERT((ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH) == 0,
326 		("ia is on in_ifaddrhashtbls\n"));
327 
328 	ifac->ifa_listmask |= IFA_LIST_IN_IFADDRHASH;
329 	iac = &ifac->ifa_proto_u.u_in_ifac;
330 	LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr),
331 			 iac, ia_hash);
332 
333 	crit_exit();
334 
335 	ifa_forwardmsg(&msg->lmsg, cpu + 1);
336 }
337 
338 static void
339 in_iahashrem_dispatch(netmsg_t msg)
340 {
341 	struct in_ifaddr *ia = msg->lmsg.u.ms_resultp;
342 	struct ifaddr_container *ifac;
343 	struct in_ifaddr_container *iac;
344 	int cpu = mycpuid;
345 
346 	crit_enter();
347 
348 	ifac = &ia->ia_ifa.ifa_containers[cpu];
349 	ASSERT_IFAC_VALID(ifac);
350 	KASSERT(ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH,
351 		("ia is not on in_ifaddrhashtbls\n"));
352 
353 	iac = &ifac->ifa_proto_u.u_in_ifac;
354 	LIST_REMOVE(iac, ia_hash);
355 	ifac->ifa_listmask &= ~IFA_LIST_IN_IFADDRHASH;
356 
357 	crit_exit();
358 
359 	ifa_forwardmsg(&msg->lmsg, cpu + 1);
360 }
361 
362 static void
363 in_ialink(struct in_ifaddr *ia)
364 {
365 	struct netmsg_base msg;
366 
367 	netmsg_init(&msg, NULL, &curthread->td_msgport,
368 		    0, in_ialink_dispatch);
369 	msg.lmsg.u.ms_resultp = ia;
370 
371 	ifa_domsg(&msg.lmsg, 0);
372 }
373 
374 void
375 in_iaunlink(struct in_ifaddr *ia)
376 {
377 	struct netmsg_base msg;
378 
379 	netmsg_init(&msg, NULL, &curthread->td_msgport,
380 		    0, in_iaunlink_dispatch);
381 	msg.lmsg.u.ms_resultp = ia;
382 
383 	ifa_domsg(&msg.lmsg, 0);
384 }
385 
386 void
387 in_iahash_insert(struct in_ifaddr *ia)
388 {
389 	struct netmsg_base msg;
390 
391 	netmsg_init(&msg, NULL, &curthread->td_msgport,
392 		    0, in_iahashins_dispatch);
393 	msg.lmsg.u.ms_resultp = ia;
394 
395 	ifa_domsg(&msg.lmsg, 0);
396 }
397 
398 void
399 in_iahash_remove(struct in_ifaddr *ia)
400 {
401 	struct netmsg_base msg;
402 
403 	netmsg_init(&msg, NULL, &curthread->td_msgport,
404 		    0, in_iahashrem_dispatch);
405 	msg.lmsg.u.ms_resultp = ia;
406 
407 	ifa_domsg(&msg.lmsg, 0);
408 }
409 
410 static __inline struct in_ifaddr *
411 in_ianext(struct in_ifaddr *oia)
412 {
413 	struct ifaddr_container *ifac;
414 	struct in_ifaddr_container *iac;
415 
416 	ifac = &oia->ia_ifa.ifa_containers[mycpuid];
417 	ASSERT_IFAC_VALID(ifac);
418 	KASSERT(ifac->ifa_listmask & IFA_LIST_IN_IFADDRHEAD,
419 		("ia is not on in_ifaddrheads\n"));
420 
421 	iac = &ifac->ifa_proto_u.u_in_ifac;
422 	iac = TAILQ_NEXT(iac, ia_link);
423 	if (iac != NULL)
424 		return iac->ia;
425 	else
426 		return NULL;
427 }
428 
429 static int
430 in_control_internal(u_long cmd, caddr_t data, struct ifnet *ifp,
431 		    struct thread *td)
432 {
433 	struct ifreq *ifr = (struct ifreq *)data;
434 	struct in_ifaddr *ia = NULL;
435 	struct in_addr dst;
436 	struct in_aliasreq *ifra = (struct in_aliasreq *)data;
437 	struct ifaddr_container *ifac;
438 	struct in_ifaddr_container *iac;
439 	struct sockaddr_in oldaddr;
440 	int hostIsNew, iaIsNew, maskIsNew, ifpWasUp;
441 	int error = 0;
442 
443 	iaIsNew = 0;
444 	ifpWasUp = 0;
445 
446 	/*
447 	 * Find address for this interface, if it exists.
448 	 *
449 	 * If an alias address was specified, find that one instead of
450 	 * the first one on the interface, if possible
451 	 */
452 	if (ifp) {
453 		struct in_ifaddr *iap;
454 
455 		dst = ((struct sockaddr_in *)&ifr->ifr_addr)->sin_addr;
456 		LIST_FOREACH(iac, INADDR_HASH(dst.s_addr), ia_hash) {
457 			iap = iac->ia;
458 			if (iap->ia_ifp == ifp &&
459 			    iap->ia_addr.sin_addr.s_addr == dst.s_addr) {
460 				ia = iap;
461 				break;
462 			}
463 		}
464 		if (ia == NULL) {
465 			TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid],
466 				      ifa_link) {
467 				iap = ifatoia(ifac->ifa);
468 				if (iap->ia_addr.sin_family == AF_INET) {
469 					ia = iap;
470 					break;
471 				}
472 			}
473 		}
474 
475 		if (ifp->if_flags & IFF_UP)
476 			ifpWasUp = 1;
477 	}
478 
479 	switch (cmd) {
480 	case SIOCAIFADDR:
481 	case SIOCDIFADDR:
482 		if (ifp == NULL)
483 			return (EADDRNOTAVAIL);
484 		if (ifra->ifra_addr.sin_family == AF_INET) {
485 			while (ia != NULL) {
486 				if (ia->ia_ifp == ifp  &&
487 				    ia->ia_addr.sin_addr.s_addr ==
488 				    ifra->ifra_addr.sin_addr.s_addr)
489 					break;
490 				ia = in_ianext(ia);
491 			}
492 			if ((ifp->if_flags & IFF_POINTOPOINT) &&
493 			    cmd == SIOCAIFADDR &&
494 			    ifra->ifra_dstaddr.sin_addr.s_addr == INADDR_ANY) {
495 				return EDESTADDRREQ;
496 			}
497 		}
498 		if (cmd == SIOCDIFADDR && ia == NULL)
499 			return (EADDRNOTAVAIL);
500 		/* FALLTHROUGH */
501 	case SIOCSIFADDR:
502 	case SIOCSIFNETMASK:
503 	case SIOCSIFDSTADDR:
504 		if (td && (error = priv_check(td, PRIV_ROOT)) != 0)
505 			return error;
506 
507 		if (ifp == NULL)
508 			return (EADDRNOTAVAIL);
509 
510 		if (cmd == SIOCSIFDSTADDR &&
511 		    (ifp->if_flags & IFF_POINTOPOINT) == 0)
512 			return (EINVAL);
513 
514 		if (ia == NULL) {
515 			struct ifaddr *ifa;
516 			int i;
517 
518 			ia = ifa_create(sizeof(*ia), M_WAITOK);
519 			ifa = &ia->ia_ifa;
520 
521 			/*
522 			 * Setup per-CPU information
523 			 */
524 			for (i = 0; i < ncpus; ++i) {
525 				ifac = &ifa->ifa_containers[i];
526 				iac = &ifac->ifa_proto_u.u_in_ifac;
527 				iac->ia = ia;
528 				iac->ia_ifac = ifac;
529 			}
530 
531 			/*
532 			 * Protect from NETISR_IP traversing address list
533 			 * while we're modifying it.
534 			 */
535 			crit_enter();
536 
537 			in_ialink(ia);
538 			ifa_iflink(ifa, ifp, 1);
539 
540 			ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr;
541 			ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
542 			ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask;
543 			ia->ia_sockmask.sin_len = 8;
544 			ia->ia_sockmask.sin_family = AF_INET;
545 			if (ifp->if_flags & IFF_BROADCAST) {
546 				ia->ia_broadaddr.sin_len = sizeof ia->ia_addr;
547 				ia->ia_broadaddr.sin_family = AF_INET;
548 			}
549 			ia->ia_ifp = ifp;
550 			if (!(ifp->if_flags & IFF_LOOPBACK))
551 				in_interfaces++;
552 			iaIsNew = 1;
553 
554 			crit_exit();
555 		}
556 		break;
557 
558 	case SIOCSIFBRDADDR:
559 		if (td && (error = priv_check(td, PRIV_ROOT)) != 0)
560 			return error;
561 		/* FALLTHROUGH */
562 
563 	case SIOCGIFADDR:
564 	case SIOCGIFNETMASK:
565 	case SIOCGIFDSTADDR:
566 	case SIOCGIFBRDADDR:
567 		if (ia == NULL)
568 			return (EADDRNOTAVAIL);
569 		break;
570 	}
571 
572 	switch (cmd) {
573 	case SIOCGIFADDR:
574 		*((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_addr;
575 		return (0);
576 
577 	case SIOCGIFBRDADDR:
578 		if ((ifp->if_flags & IFF_BROADCAST) == 0)
579 			return (EINVAL);
580 		*((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_broadaddr;
581 		return (0);
582 
583 	case SIOCGIFDSTADDR:
584 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
585 			return (EINVAL);
586 		*((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_dstaddr;
587 		return (0);
588 
589 	case SIOCGIFNETMASK:
590 		*((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_sockmask;
591 		return (0);
592 
593 	case SIOCSIFDSTADDR:
594 		KKASSERT(ifp->if_flags & IFF_POINTOPOINT);
595 
596 		oldaddr = ia->ia_dstaddr;
597 		ia->ia_dstaddr = *(struct sockaddr_in *)&ifr->ifr_dstaddr;
598 		if (ifp->if_ioctl != NULL) {
599 			ifnet_serialize_all(ifp);
600 			error = ifp->if_ioctl(ifp, SIOCSIFDSTADDR, (caddr_t)ia,
601 					      td->td_proc->p_ucred);
602 			ifnet_deserialize_all(ifp);
603 			if (error) {
604 				ia->ia_dstaddr = oldaddr;
605 				return (error);
606 			}
607 		}
608 		if (ia->ia_flags & IFA_ROUTE) {
609 			ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr;
610 			rtinit(&ia->ia_ifa, RTM_DELETE, RTF_HOST);
611 			ia->ia_ifa.ifa_dstaddr =
612 					(struct sockaddr *)&ia->ia_dstaddr;
613 			rtinit(&ia->ia_ifa, RTM_ADD, RTF_HOST | RTF_UP);
614 		}
615 		return (0);
616 
617 	case SIOCSIFBRDADDR:
618 		if ((ifp->if_flags & IFF_BROADCAST) == 0)
619 			return (EINVAL);
620 		ia->ia_broadaddr = *(struct sockaddr_in *)&ifr->ifr_broadaddr;
621 		return (0);
622 
623 	case SIOCSIFADDR:
624 		error = in_ifinit(ifp, ia,
625 		    (const struct sockaddr_in *)&ifr->ifr_addr, 1);
626 		if (error != 0 && iaIsNew)
627 			break;
628 		if (error == 0) {
629 			EVENTHANDLER_INVOKE(ifaddr_event, ifp,
630 			iaIsNew ? IFADDR_EVENT_ADD : IFADDR_EVENT_CHANGE,
631 			&ia->ia_ifa);
632 		}
633 		if (!ifpWasUp && (ifp->if_flags & IFF_UP)) {
634 			/*
635 			 * Interface is brought up by in_ifinit()
636 			 * (via ifp->if_ioctl).  We act as if the
637 			 * interface got IFF_UP flag turned on.
638 			 */
639 			if_up(ifp);
640 		}
641 		return (0);
642 
643 	case SIOCSIFNETMASK:
644 		ia->ia_sockmask.sin_addr = ifra->ifra_addr.sin_addr;
645 		ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr);
646 		return (0);
647 
648 	case SIOCAIFADDR:
649 		maskIsNew = 0;
650 		hostIsNew = 1;
651 		error = 0;
652 		if (ia->ia_addr.sin_family == AF_INET) {
653 			if (ifra->ifra_addr.sin_len == 0) {
654 				ifra->ifra_addr = ia->ia_addr;
655 				hostIsNew = 0;
656 			} else if (ifra->ifra_addr.sin_addr.s_addr ==
657 				   ia->ia_addr.sin_addr.s_addr) {
658 				hostIsNew = 0;
659 			}
660 		}
661 		if (ifra->ifra_mask.sin_len) {
662 			in_ifscrub(ifp, ia);
663 			ia->ia_sockmask = ifra->ifra_mask;
664 			ia->ia_sockmask.sin_family = AF_INET;
665 			ia->ia_subnetmask =
666 			    ntohl(ia->ia_sockmask.sin_addr.s_addr);
667 			maskIsNew = 1;
668 		}
669 		if ((ifp->if_flags & IFF_POINTOPOINT) &&
670 		    ifra->ifra_dstaddr.sin_family == AF_INET) {
671 			in_ifscrub(ifp, ia);
672 			ia->ia_dstaddr = ifra->ifra_dstaddr;
673 			maskIsNew  = 1; /* We lie; but the effect's the same */
674 		}
675 		if (ifra->ifra_addr.sin_family == AF_INET &&
676 		    (hostIsNew || maskIsNew))
677 			error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
678 
679 		if (error != 0 && iaIsNew)
680 			break;
681 
682 		if ((ifp->if_flags & IFF_BROADCAST) &&
683 		    ifra->ifra_broadaddr.sin_family == AF_INET)
684 			ia->ia_broadaddr = ifra->ifra_broadaddr;
685 		if (error == 0) {
686 			EVENTHANDLER_INVOKE(ifaddr_event, ifp,
687 			iaIsNew ? IFADDR_EVENT_ADD : IFADDR_EVENT_CHANGE,
688 			&ia->ia_ifa);
689 		}
690 		if (!ifpWasUp && (ifp->if_flags & IFF_UP)) {
691 			/* See the comment in SIOCSIFADDR */
692 			if_up(ifp);
693 		}
694 		return (error);
695 
696 	case SIOCDIFADDR:
697 		/*
698 		 * in_ifscrub kills the interface route.
699 		 */
700 		in_ifscrub(ifp, ia);
701 		/*
702 		 * in_ifadown gets rid of all the rest of
703 		 * the routes.  This is not quite the right
704 		 * thing to do, but at least if we are running
705 		 * a routing process they will come back.
706 		 */
707 		in_ifadown(&ia->ia_ifa, 1);
708 		EVENTHANDLER_INVOKE(ifaddr_event, ifp, IFADDR_EVENT_DELETE,
709 				    &ia->ia_ifa);
710 		error = 0;
711 		break;
712 
713 	default:
714 		if (ifp == NULL || ifp->if_ioctl == NULL)
715 			return (EOPNOTSUPP);
716 		ifnet_serialize_all(ifp);
717 		error = ifp->if_ioctl(ifp, cmd, data, td->td_proc->p_ucred);
718 		ifnet_deserialize_all(ifp);
719 		return (error);
720 	}
721 
722 	KKASSERT(cmd == SIOCDIFADDR ||
723 		 ((cmd == SIOCAIFADDR || cmd == SIOCSIFADDR) && iaIsNew));
724 
725 	ifa_ifunlink(&ia->ia_ifa, ifp);
726 	in_iaunlink(ia);
727 
728 	if (cmd == SIOCDIFADDR) {
729 		ifac = &ia->ia_ifa.ifa_containers[mycpuid];
730 		if (ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH)
731 			in_iahash_remove(ia);
732 	}
733 #ifdef INVARIANTS
734 	else {
735 		/*
736 		 * If cmd is SIOCSIFADDR or SIOCAIFADDR, in_ifinit() has
737 		 * already taken care of the deletion from hash table
738 		 */
739 		ifac = &ia->ia_ifa.ifa_containers[mycpuid];
740 		KASSERT((ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH) == 0,
741 			("SIOC%cIFADDR failed on new ia, "
742 			 "but the new ia is still in hash table\n",
743 			 cmd == SIOCSIFADDR ? 'S' : 'A'));
744 	}
745 #endif
746 
747 	ifa_destroy(&ia->ia_ifa);
748 
749 	if ((cmd == SIOCAIFADDR || cmd == SIOCSIFADDR) &&
750 	    !ifpWasUp && (ifp->if_flags & IFF_UP)) {
751 		/*
752 		 * Though the address assignment failed, the
753 		 * interface is brought up by in_ifinit()
754 		 * (via ifp->if_ioctl).  With the hope that
755 		 * the interface has some valid addresses, we
756 		 * act as if IFF_UP flag was just set on the
757 		 * interface.
758 		 *
759 		 * NOTE:
760 		 * This could only be done after the failed
761 		 * address is unlinked from the global address
762 		 * list.
763 		 */
764 		if_up(ifp);
765 	}
766 
767 	return (error);
768 }
769 
770 /*
771  * SIOC[GAD]LIFADDR.
772  *	SIOCGLIFADDR: get first address. (?!?)
773  *	SIOCGLIFADDR with IFLR_PREFIX:
774  *		get first address that matches the specified prefix.
775  *	SIOCALIFADDR: add the specified address.
776  *	SIOCALIFADDR with IFLR_PREFIX:
777  *		EINVAL since we can't deduce hostid part of the address.
778  *	SIOCDLIFADDR: delete the specified address.
779  *	SIOCDLIFADDR with IFLR_PREFIX:
780  *		delete the first address that matches the specified prefix.
781  * return values:
782  *	EINVAL on invalid parameters
783  *	EADDRNOTAVAIL on prefix match failed/specified address not found
784  *	other values may be returned from in_ioctl()
785  *
786  * NOTE! td might be NULL.
787  */
788 static int
789 in_lifaddr_ioctl(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp,
790 		 struct thread *td)
791 {
792 	struct if_laddrreq *iflr = (struct if_laddrreq *)data;
793 
794 	/* sanity checks */
795 	if (!data || !ifp) {
796 		panic("invalid argument to in_lifaddr_ioctl");
797 		/*NOTRECHED*/
798 	}
799 
800 	switch (cmd) {
801 	case SIOCGLIFADDR:
802 		/* address must be specified on GET with IFLR_PREFIX */
803 		if ((iflr->flags & IFLR_PREFIX) == 0)
804 			break;
805 		/*FALLTHROUGH*/
806 	case SIOCALIFADDR:
807 	case SIOCDLIFADDR:
808 		/* address must be specified on ADD and DELETE */
809 		if (iflr->addr.ss_family != AF_INET)
810 			return EINVAL;
811 		if (iflr->addr.ss_len != sizeof(struct sockaddr_in))
812 			return EINVAL;
813 		/* XXX need improvement */
814 		if (iflr->dstaddr.ss_family
815 		 && iflr->dstaddr.ss_family != AF_INET)
816 			return EINVAL;
817 		if (iflr->dstaddr.ss_family
818 		 && iflr->dstaddr.ss_len != sizeof(struct sockaddr_in))
819 			return EINVAL;
820 		break;
821 	default: /*shouldn't happen*/
822 		return EOPNOTSUPP;
823 	}
824 	if (sizeof(struct in_addr) * 8 < iflr->prefixlen)
825 		return EINVAL;
826 
827 	switch (cmd) {
828 	case SIOCALIFADDR:
829 	    {
830 		struct in_aliasreq ifra;
831 
832 		if (iflr->flags & IFLR_PREFIX)
833 			return EINVAL;
834 
835 		/* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
836 		bzero(&ifra, sizeof ifra);
837 		bcopy(iflr->iflr_name, ifra.ifra_name, sizeof ifra.ifra_name);
838 
839 		bcopy(&iflr->addr, &ifra.ifra_addr, iflr->addr.ss_len);
840 
841 		if (iflr->dstaddr.ss_family) {	/*XXX*/
842 			bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
843 				iflr->dstaddr.ss_len);
844 		}
845 
846 		ifra.ifra_mask.sin_family = AF_INET;
847 		ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
848 		in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);
849 
850 		return in_control(so, SIOCAIFADDR, (caddr_t)&ifra, ifp, td);
851 	    }
852 	case SIOCGLIFADDR:
853 	case SIOCDLIFADDR:
854 	    {
855 		struct ifaddr_container *ifac;
856 		struct in_ifaddr *ia;
857 		struct in_addr mask, candidate, match;
858 		struct sockaddr_in *sin;
859 		int cmp;
860 
861 		bzero(&mask, sizeof mask);
862 		if (iflr->flags & IFLR_PREFIX) {
863 			/* lookup a prefix rather than address. */
864 			in_len2mask(&mask, iflr->prefixlen);
865 
866 			sin = (struct sockaddr_in *)&iflr->addr;
867 			match.s_addr = sin->sin_addr.s_addr;
868 			match.s_addr &= mask.s_addr;
869 
870 			/* if you set extra bits, that's wrong */
871 			if (match.s_addr != sin->sin_addr.s_addr)
872 				return EINVAL;
873 
874 			cmp = 1;
875 		} else {
876 			if (cmd == SIOCGLIFADDR) {
877 				/* on getting an address, take the 1st match */
878 				match.s_addr = 0; /* gcc4 warning */
879 				cmp = 0;	/*XXX*/
880 			} else {
881 				/* on deleting an address, do exact match */
882 				in_len2mask(&mask, 32);
883 				sin = (struct sockaddr_in *)&iflr->addr;
884 				match.s_addr = sin->sin_addr.s_addr;
885 
886 				cmp = 1;
887 			}
888 		}
889 
890 		TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
891 			struct ifaddr *ifa = ifac->ifa;
892 
893 			if (ifa->ifa_addr->sa_family != AF_INET6)
894 				continue;
895 			if (!cmp)
896 				break;
897 			candidate.s_addr =
898 			((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr;
899 			candidate.s_addr &= mask.s_addr;
900 			if (candidate.s_addr == match.s_addr)
901 				break;
902 		}
903 		if (ifac == NULL)
904 			return EADDRNOTAVAIL;
905 		ia = (struct in_ifaddr *)(ifac->ifa);
906 
907 		if (cmd == SIOCGLIFADDR) {
908 			/* fill in the if_laddrreq structure */
909 			bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len);
910 
911 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
912 				bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
913 					ia->ia_dstaddr.sin_len);
914 			} else
915 				bzero(&iflr->dstaddr, sizeof iflr->dstaddr);
916 
917 			iflr->prefixlen =
918 				in_mask2len(&ia->ia_sockmask.sin_addr);
919 
920 			iflr->flags = 0;	/*XXX*/
921 
922 			return 0;
923 		} else {
924 			struct in_aliasreq ifra;
925 
926 			/* fill in_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
927 			bzero(&ifra, sizeof ifra);
928 			bcopy(iflr->iflr_name, ifra.ifra_name,
929 				sizeof ifra.ifra_name);
930 
931 			bcopy(&ia->ia_addr, &ifra.ifra_addr,
932 				ia->ia_addr.sin_len);
933 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
934 				bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
935 					ia->ia_dstaddr.sin_len);
936 			}
937 			bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr,
938 				ia->ia_sockmask.sin_len);
939 
940 			return in_control(so, SIOCDIFADDR, (caddr_t)&ifra,
941 					  ifp, td);
942 		}
943 	    }
944 	}
945 
946 	return EOPNOTSUPP;	/*just for safety*/
947 }
948 
949 /*
950  * Delete any existing route for an interface.
951  */
952 void
953 in_ifscrub(struct ifnet *ifp __unused, struct in_ifaddr *ia)
954 {
955 	in_scrubprefix(ia);
956 }
957 
958 /*
959  * Initialize an interface's internet address
960  * and routing table entry.
961  */
962 static int
963 in_ifinit(struct ifnet *ifp, struct in_ifaddr *ia,
964 	  const struct sockaddr_in *sin, int scrub)
965 {
966 	u_long i = ntohl(sin->sin_addr.s_addr);
967 	struct sockaddr_in oldaddr;
968 	struct ifaddr_container *ifac;
969 	int flags = RTF_UP, error = 0;
970 	int was_hash = 0;
971 
972 	ifac = &ia->ia_ifa.ifa_containers[mycpuid];
973 	oldaddr = ia->ia_addr;
974 
975 	if (ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH) {
976 		was_hash = 1;
977 		in_iahash_remove(ia);
978 	}
979 
980 	ia->ia_addr = *sin;
981 	if (ia->ia_addr.sin_family == AF_INET)
982 		in_iahash_insert(ia);
983 
984 	/*
985 	 * Give the interface a chance to initialize
986 	 * if this is its first address,
987 	 * and to validate the address if necessary.
988 	 */
989 	if (ifp->if_ioctl != NULL) {
990 		ifnet_serialize_all(ifp);
991 		error = ifp->if_ioctl(ifp, SIOCSIFADDR, (caddr_t)ia, NULL);
992 		ifnet_deserialize_all(ifp);
993 		if (error)
994 			goto fail;
995 	}
996 
997 	/*
998 	 * Delete old route, if requested.
999 	 */
1000 	if (scrub) {
1001 		ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
1002 		in_ifscrub(ifp, ia);
1003 		ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
1004 	}
1005 
1006 	/*
1007 	 * Calculate netmask/subnetmask.
1008 	 */
1009 	if (IN_CLASSA(i))
1010 		ia->ia_netmask = IN_CLASSA_NET;
1011 	else if (IN_CLASSB(i))
1012 		ia->ia_netmask = IN_CLASSB_NET;
1013 	else
1014 		ia->ia_netmask = IN_CLASSC_NET;
1015 	/*
1016 	 * The subnet mask usually includes at least the standard network part,
1017 	 * but may may be smaller in the case of supernetting.
1018 	 * If it is set, we believe it.
1019 	 */
1020 	if (ia->ia_subnetmask == 0) {
1021 		ia->ia_subnetmask = ia->ia_netmask;
1022 		ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask);
1023 	} else {
1024 		ia->ia_netmask &= ia->ia_subnetmask;
1025 	}
1026 	ia->ia_net = i & ia->ia_netmask;
1027 	ia->ia_subnet = i & ia->ia_subnetmask;
1028 	in_socktrim(&ia->ia_sockmask);
1029 
1030 	/*
1031 	 * Add route for the network.
1032 	 */
1033 	ia->ia_ifa.ifa_metric = ifp->if_metric;
1034 	if (ifp->if_flags & IFF_BROADCAST) {
1035 		ia->ia_broadaddr.sin_addr.s_addr =
1036 			htonl(ia->ia_subnet | ~ia->ia_subnetmask);
1037 		ia->ia_netbroadcast.s_addr =
1038 			htonl(ia->ia_net | ~ ia->ia_netmask);
1039 	} else if (ifp->if_flags & IFF_LOOPBACK) {
1040 		ia->ia_dstaddr = ia->ia_addr;
1041 		flags |= RTF_HOST;
1042 	} else if (ifp->if_flags & IFF_POINTOPOINT) {
1043 		if (ia->ia_dstaddr.sin_family != AF_INET)
1044 			return (0);
1045 		flags |= RTF_HOST;
1046 	}
1047 
1048 	/*-
1049 	 * Don't add host routes for interface addresses of
1050 	 * 0.0.0.0 --> 0.255.255.255 netmask 255.0.0.0.  This makes it
1051 	 * possible to assign several such address pairs with consistent
1052 	 * results (no host route) and is required by BOOTP.
1053 	 *
1054 	 * XXX: This is ugly !  There should be a way for the caller to
1055 	 *      say that they don't want a host route.
1056 	 */
1057 	if (ia->ia_addr.sin_addr.s_addr != INADDR_ANY ||
1058 	    ia->ia_netmask != IN_CLASSA_NET ||
1059 	    ia->ia_dstaddr.sin_addr.s_addr != htonl(IN_CLASSA_HOST)) {
1060 		error = in_addprefix(ia, flags);
1061 		if (error)
1062 			goto fail;
1063 	}
1064 
1065 	/*
1066 	 * If the interface supports multicast, join the "all hosts"
1067 	 * multicast group on that interface.
1068 	 */
1069 	if (ifp->if_flags & IFF_MULTICAST) {
1070 		struct in_addr addr;
1071 
1072 		addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
1073 		in_addmulti(&addr, ifp);
1074 	}
1075 	return (0);
1076 fail:
1077 	if (ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH)
1078 		in_iahash_remove(ia);
1079 
1080 	ia->ia_addr = oldaddr;
1081 	if (was_hash)
1082 		in_iahash_insert(ia);
1083 	return (error);
1084 }
1085 
1086 #define rtinitflags(x) \
1087 	(((x)->ia_ifp->if_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) \
1088 	 ? RTF_HOST : 0)
1089 
1090 /*
1091  * Add a route to prefix ("connected route" in cisco terminology).
1092  * Do nothing, if there are some interface addresses with the same
1093  * prefix already.  This function assumes that the 'target' parent
1094  * interface is UP.
1095  */
1096 static int
1097 in_addprefix(struct in_ifaddr *target, int flags)
1098 {
1099 	struct in_ifaddr_container *iac;
1100 	struct in_addr prefix, mask;
1101 	int error;
1102 
1103 	mask = target->ia_sockmask.sin_addr;
1104 	if (flags & RTF_HOST) {
1105 		prefix = target->ia_dstaddr.sin_addr;
1106 	} else {
1107 		prefix = target->ia_addr.sin_addr;
1108 		prefix.s_addr &= mask.s_addr;
1109 	}
1110 
1111 	TAILQ_FOREACH(iac, &in_ifaddrheads[mycpuid], ia_link) {
1112 		struct in_ifaddr *ia = iac->ia;
1113 		struct in_addr p;
1114 
1115 		/* Don't test against self */
1116 		if (ia == target)
1117 			continue;
1118 
1119 		/* The tested address does not own a route entry */
1120 		if ((ia->ia_flags & IFA_ROUTE) == 0)
1121 			continue;
1122 
1123 		/* Prefix test */
1124 		if (rtinitflags(ia)) {
1125 			p = ia->ia_dstaddr.sin_addr;
1126 		} else {
1127 			p = ia->ia_addr.sin_addr;
1128 			p.s_addr &= ia->ia_sockmask.sin_addr.s_addr;
1129 		}
1130 		if (prefix.s_addr != p.s_addr)
1131 			continue;
1132 
1133 		/*
1134 		 * If the to-be-added address and the curretly being
1135 		 * tested address are not host addresses, we need to
1136 		 * take subnetmask into consideration.
1137 		 */
1138 		if (!(flags & RTF_HOST) && !rtinitflags(ia) &&
1139 		    mask.s_addr != ia->ia_sockmask.sin_addr.s_addr)
1140 			continue;
1141 
1142 		/*
1143 		 * If we got a matching prefix route inserted by other
1144 		 * interface address, we don't need to bother.
1145 		 */
1146 		return 0;
1147 	}
1148 
1149 	/*
1150 	 * No one seem to have prefix route; insert it.
1151 	 */
1152 	error = rtinit(&target->ia_ifa, RTM_ADD, flags);
1153 	if (!error)
1154 		target->ia_flags |= IFA_ROUTE;
1155 	return error;
1156 }
1157 
1158 /*
1159  * Remove a route to prefix ("connected route" in cisco terminology).
1160  * Re-installs the route by using another interface address, if there's
1161  * one with the same prefix (otherwise we lose the route mistakenly).
1162  */
1163 static void
1164 in_scrubprefix(struct in_ifaddr *target)
1165 {
1166 	struct in_ifaddr_container *iac;
1167 	struct in_addr prefix, mask;
1168 	int error;
1169 
1170 	if ((target->ia_flags & IFA_ROUTE) == 0)
1171 		return;
1172 
1173 	mask = target->ia_sockmask.sin_addr;
1174 	if (rtinitflags(target)) {
1175 		prefix = target->ia_dstaddr.sin_addr;
1176 	} else {
1177 		prefix = target->ia_addr.sin_addr;
1178 		prefix.s_addr &= mask.s_addr;
1179 	}
1180 
1181 	TAILQ_FOREACH(iac, &in_ifaddrheads[mycpuid], ia_link) {
1182 		struct in_ifaddr *ia = iac->ia;
1183 		struct in_addr p;
1184 
1185 		/* Don't test against self */
1186 		if (ia == target)
1187 			continue;
1188 
1189 		/* The tested address already owns a route entry */
1190 		if (ia->ia_flags & IFA_ROUTE)
1191 			continue;
1192 
1193 		/*
1194 		 * The prefix route of the tested address should
1195 		 * never be installed if its parent interface is
1196 		 * not UP yet.
1197 		 */
1198 		if ((ia->ia_ifp->if_flags & IFF_UP) == 0)
1199 			continue;
1200 
1201 		/* Prefix test */
1202 		if (rtinitflags(ia)) {
1203 			p = ia->ia_dstaddr.sin_addr;
1204 		} else {
1205 			p = ia->ia_addr.sin_addr;
1206 			p.s_addr &= ia->ia_sockmask.sin_addr.s_addr;
1207 		}
1208 		if (prefix.s_addr != p.s_addr)
1209 			continue;
1210 
1211 		/*
1212 		 * We don't need to test subnetmask here, as what we do
1213 		 * in in_addprefix(), since if the the tested address's
1214 		 * parent interface is UP, the tested address should own
1215 		 * a prefix route entry and we would never reach here.
1216 		 */
1217 
1218 		/*
1219 		 * If we got a matching prefix route, move IFA_ROUTE to him
1220 		 */
1221 		rtinit(&target->ia_ifa, RTM_DELETE, rtinitflags(target));
1222 		target->ia_flags &= ~IFA_ROUTE;
1223 
1224 		error = rtinit(&ia->ia_ifa, RTM_ADD, rtinitflags(ia) | RTF_UP);
1225 		if (!error)
1226 			ia->ia_flags |= IFA_ROUTE;
1227 		return;
1228 	}
1229 
1230 	/*
1231 	 * No candidates for this prefix route; just remove it.
1232 	 */
1233 	rtinit(&target->ia_ifa, RTM_DELETE, rtinitflags(target));
1234 	target->ia_flags &= ~IFA_ROUTE;
1235 }
1236 
1237 #undef rtinitflags
1238 
1239 /*
1240  * Return 1 if the address might be a local broadcast address.
1241  */
1242 int
1243 in_broadcast(struct in_addr in, struct ifnet *ifp)
1244 {
1245 	struct ifaddr_container *ifac;
1246 	u_long t;
1247 
1248 	if (in.s_addr == INADDR_BROADCAST ||
1249 	    in.s_addr == INADDR_ANY)
1250 		return 1;
1251 	if ((ifp->if_flags & IFF_BROADCAST) == 0)
1252 		return 0;
1253 	t = ntohl(in.s_addr);
1254 	/*
1255 	 * Look through the list of addresses for a match
1256 	 * with a broadcast address.
1257 	 */
1258 #define ia ((struct in_ifaddr *)ifa)
1259 	TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
1260 		struct ifaddr *ifa = ifac->ifa;
1261 
1262 		if (ifa->ifa_addr->sa_family == AF_INET &&
1263 		    (in.s_addr == ia->ia_broadaddr.sin_addr.s_addr ||
1264 		     in.s_addr == ia->ia_netbroadcast.s_addr ||
1265 		     /*
1266 		      * Check for old-style (host 0) broadcast.
1267 		      */
1268 		     t == ia->ia_subnet || t == ia->ia_net) &&
1269 		     /*
1270 		      * Check for an all one subnetmask. These
1271 		      * only exist when an interface gets a secondary
1272 		      * address.
1273 		      */
1274 		     ia->ia_subnetmask != (u_long)0xffffffff)
1275 			    return 1;
1276 	}
1277 	return (0);
1278 #undef ia
1279 }
1280 /*
1281  * Add an address to the list of IP multicast addresses for a given interface.
1282  */
1283 struct in_multi *
1284 in_addmulti(struct in_addr *ap, struct ifnet *ifp)
1285 {
1286 	struct in_multi *inm;
1287 	int error;
1288 	struct sockaddr_in sin;
1289 	struct ifmultiaddr *ifma;
1290 
1291 	/*
1292 	 * Call generic routine to add membership or increment
1293 	 * refcount.  It wants addresses in the form of a sockaddr,
1294 	 * so we build one here (being careful to zero the unused bytes).
1295 	 */
1296 	bzero(&sin, sizeof sin);
1297 	sin.sin_family = AF_INET;
1298 	sin.sin_len = sizeof sin;
1299 	sin.sin_addr = *ap;
1300 	crit_enter();
1301 	error = if_addmulti(ifp, (struct sockaddr *)&sin, &ifma);
1302 	if (error) {
1303 		crit_exit();
1304 		return 0;
1305 	}
1306 
1307 	/*
1308 	 * If ifma->ifma_protospec is null, then if_addmulti() created
1309 	 * a new record.  Otherwise, we are done.
1310 	 */
1311 	if (ifma->ifma_protospec != 0) {
1312 		crit_exit();
1313 		return ifma->ifma_protospec;
1314 	}
1315 
1316 	/* XXX - if_addmulti uses M_WAITOK.  Can this really be called
1317 	   at interrupt time?  If so, need to fix if_addmulti. XXX */
1318 	inm = kmalloc(sizeof *inm, M_IPMADDR, M_WAITOK | M_ZERO);
1319 	inm->inm_addr = *ap;
1320 	inm->inm_ifp = ifp;
1321 	inm->inm_ifma = ifma;
1322 	ifma->ifma_protospec = inm;
1323 	LIST_INSERT_HEAD(&in_multihead, inm, inm_link);
1324 
1325 	/*
1326 	 * Let IGMP know that we have joined a new IP multicast group.
1327 	 */
1328 	igmp_joingroup(inm);
1329 	crit_exit();
1330 	return (inm);
1331 }
1332 
1333 /*
1334  * Delete a multicast address record.
1335  */
1336 void
1337 in_delmulti(struct in_multi *inm)
1338 {
1339 	struct ifmultiaddr *ifma;
1340 	struct in_multi my_inm;
1341 
1342 	crit_enter();
1343 	ifma = inm->inm_ifma;
1344 	my_inm.inm_ifp = NULL ; /* don't send the leave msg */
1345 	if (ifma->ifma_refcount == 1) {
1346 		/*
1347 		 * No remaining claims to this record; let IGMP know that
1348 		 * we are leaving the multicast group.
1349 		 * But do it after the if_delmulti() which might reset
1350 		 * the interface and nuke the packet.
1351 		 */
1352 		my_inm = *inm ;
1353 		ifma->ifma_protospec = 0;
1354 		LIST_REMOVE(inm, inm_link);
1355 		kfree(inm, M_IPMADDR);
1356 	}
1357 	/* XXX - should be separate API for when we have an ifma? */
1358 	if_delmulti(ifma->ifma_ifp, ifma->ifma_addr);
1359 	if (my_inm.inm_ifp != NULL)
1360 		igmp_leavegroup(&my_inm);
1361 	crit_exit();
1362 }
1363 
1364 void
1365 in_ifdetach(struct ifnet *ifp)
1366 {
1367 	in_pcbpurgeif0(LIST_FIRST(&ripcbinfo.pcblisthead), ifp);
1368 	in_pcbpurgeif0(LIST_FIRST(&udbinfo.pcblisthead), ifp);
1369 }
1370