xref: /netbsd-src/sys/netinet/in.c (revision 95d875fb90b1458e4f1de6950286ddcd6644bc61)
1 /*	$NetBSD: in.c,v 1.49 1999/12/12 15:57:07 itojun 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  * 3. All advertising materials mentioning features or use of this software
49  *    must display the following acknowledgement:
50  *	This product includes software developed by the NetBSD
51  *	Foundation, Inc. and its contributors.
52  * 4. Neither the name of The NetBSD Foundation nor the names of its
53  *    contributors may be used to endorse or promote products derived
54  *    from this software without specific prior written permission.
55  *
56  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
57  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
58  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
59  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
60  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
61  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
62  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
63  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
64  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
65  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
66  * POSSIBILITY OF SUCH DAMAGE.
67  */
68 
69 /*
70  * Copyright (c) 1982, 1986, 1991, 1993
71  *	The Regents of the University of California.  All rights reserved.
72  *
73  * Redistribution and use in source and binary forms, with or without
74  * modification, are permitted provided that the following conditions
75  * are met:
76  * 1. Redistributions of source code must retain the above copyright
77  *    notice, this list of conditions and the following disclaimer.
78  * 2. Redistributions in binary form must reproduce the above copyright
79  *    notice, this list of conditions and the following disclaimer in the
80  *    documentation and/or other materials provided with the distribution.
81  * 3. All advertising materials mentioning features or use of this software
82  *    must display the following acknowledgement:
83  *	This product includes software developed by the University of
84  *	California, Berkeley and its contributors.
85  * 4. Neither the name of the University nor the names of its contributors
86  *    may be used to endorse or promote products derived from this software
87  *    without specific prior written permission.
88  *
89  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
90  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
91  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
92  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
93  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
94  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
95  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
96  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
97  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
98  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
99  * SUCH DAMAGE.
100  *
101  *	@(#)in.c	8.4 (Berkeley) 1/9/95
102  */
103 
104 #include "opt_inet.h"
105 #include "opt_inet_conf.h"
106 #include "opt_mrouting.h"
107 
108 #include <sys/param.h>
109 #include <sys/ioctl.h>
110 #include <sys/errno.h>
111 #include <sys/malloc.h>
112 #include <sys/socket.h>
113 #include <sys/socketvar.h>
114 #include <sys/systm.h>
115 #include <sys/proc.h>
116 
117 #include <net/if.h>
118 #include <net/if_types.h>
119 #include <net/route.h>
120 #include "gif.h"
121 #if NGIF > 0
122 #include <net/if_gif.h>
123 #endif
124 
125 #include <net/if_ether.h>
126 
127 #include <netinet/in_systm.h>
128 #include <netinet/in.h>
129 #include <netinet/in_var.h>
130 #include <netinet/if_inarp.h>
131 #include <netinet/ip_mroute.h>
132 #include <netinet/igmp_var.h>
133 
134 #ifdef INET
135 
136 static int in_mask2len __P((struct in_addr *));
137 static void in_len2mask __P((struct in_addr *, int));
138 static int in_lifaddr_ioctl __P((struct socket *, u_long, caddr_t,
139 	struct ifnet *, struct proc *));
140 
141 #ifndef SUBNETSARELOCAL
142 #define	SUBNETSARELOCAL	1
143 #endif
144 
145 #ifndef HOSTZEROBROADCAST
146 #define HOSTZEROBROADCAST 1
147 #endif
148 
149 int subnetsarelocal = SUBNETSARELOCAL;
150 int hostzeroisbroadcast = HOSTZEROBROADCAST;
151 
152 /*
153  * Return 1 if an internet address is for a ``local'' host
154  * (one to which we have a connection).  If subnetsarelocal
155  * is true, this includes other subnets of the local net.
156  * Otherwise, it includes only the directly-connected (sub)nets.
157  */
158 int
159 in_localaddr(in)
160 	struct in_addr in;
161 {
162 	register struct in_ifaddr *ia;
163 
164 	if (subnetsarelocal) {
165 		for (ia = in_ifaddr.tqh_first; ia != 0; ia = ia->ia_list.tqe_next)
166 			if ((in.s_addr & ia->ia_netmask) == ia->ia_net)
167 				return (1);
168 	} else {
169 		for (ia = in_ifaddr.tqh_first; ia != 0; ia = ia->ia_list.tqe_next)
170 			if ((in.s_addr & ia->ia_subnetmask) == ia->ia_subnet)
171 				return (1);
172 	}
173 	return (0);
174 }
175 
176 /*
177  * Determine whether an IP address is in a reserved set of addresses
178  * that may not be forwarded, or whether datagrams to that destination
179  * may be forwarded.
180  */
181 int
182 in_canforward(in)
183 	struct in_addr in;
184 {
185 	register u_int32_t net;
186 
187 	if (IN_EXPERIMENTAL(in.s_addr) || IN_MULTICAST(in.s_addr))
188 		return (0);
189 	if (IN_CLASSA(in.s_addr)) {
190 		net = in.s_addr & IN_CLASSA_NET;
191 		if (net == 0 || net == htonl(IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
192 			return (0);
193 	}
194 	return (1);
195 }
196 
197 /*
198  * Trim a mask in a sockaddr
199  */
200 void
201 in_socktrim(ap)
202 	struct sockaddr_in *ap;
203 {
204 	register char *cplim = (char *) &ap->sin_addr;
205 	register char *cp = (char *) (&ap->sin_addr + 1);
206 
207 	ap->sin_len = 0;
208 	while (--cp >= cplim)
209 		if (*cp) {
210 			(ap)->sin_len = cp - (char *) (ap) + 1;
211 			break;
212 		}
213 }
214 
215 /*
216  *  Routine to take an Internet address and convert into a
217  *  "dotted quad" representation for printing.
218  */
219 const char *
220 in_fmtaddr(addr)
221 	struct in_addr addr;
222 {
223 	static char buf[sizeof("123.456.789.123")];
224 
225 	addr.s_addr = ntohl(addr.s_addr);
226 
227 	sprintf(buf, "%d.%d.%d.%d",
228 		(addr.s_addr >> 24) & 0xFF,
229 		(addr.s_addr >> 16) & 0xFF,
230 		(addr.s_addr >>  8) & 0xFF,
231 		(addr.s_addr >>  0) & 0xFF);
232 	return buf;
233 }
234 
235 /*
236  * Maintain the "in_maxmtu" variable, which is the largest
237  * mtu for non-local interfaces with AF_INET addresses assigned
238  * to them that are up.
239  */
240 unsigned long in_maxmtu;
241 
242 void
243 in_setmaxmtu()
244 {
245 	register struct in_ifaddr *ia;
246 	register struct ifnet *ifp;
247 	unsigned long maxmtu = 0;
248 
249 	for (ia = in_ifaddr.tqh_first; ia != 0; ia = ia->ia_list.tqe_next) {
250 		if ((ifp = ia->ia_ifp) == 0)
251 			continue;
252 		if ((ifp->if_flags & (IFF_UP|IFF_LOOPBACK)) != IFF_UP)
253 			continue;
254 		if (ifp->if_mtu > maxmtu)
255 			maxmtu = ifp->if_mtu;
256 	}
257 	if (maxmtu)
258 		in_maxmtu = maxmtu;
259 }
260 
261 static int
262 in_mask2len(mask)
263 	struct in_addr *mask;
264 {
265 	int x, y;
266 	u_char *p;
267 
268 	p = (u_char *)mask;
269 	for (x = 0; x < sizeof(*mask); x++) {
270 		if (p[x] != 0xff)
271 			break;
272 	}
273 	y = 0;
274 	if (x < sizeof(*mask)) {
275 		for (y = 0; y < 8; y++) {
276 			if ((p[x] & (0x80 >> y)) == 0)
277 				break;
278 		}
279 	}
280 	return x * 8 + y;
281 }
282 
283 static void
284 in_len2mask(mask, len)
285 	struct in_addr *mask;
286 	int len;
287 {
288 	int i;
289 	u_char *p;
290 
291 	p = (u_char *)mask;
292 	bzero(mask, sizeof(*mask));
293 	for (i = 0; i < len / 8; i++)
294 		p[i] = 0xff;
295 	if (len % 8)
296 		p[i] = (0xff00 >> (len % 8)) & 0xff;
297 }
298 
299 int	in_interfaces;		/* number of external internet interfaces */
300 
301 /*
302  * Generic internet control operations (ioctl's).
303  * Ifp is 0 if not an interface-specific ioctl.
304  */
305 /* ARGSUSED */
306 int
307 in_control(so, cmd, data, ifp, p)
308 	struct socket *so;
309 	u_long cmd;
310 	caddr_t data;
311 	register struct ifnet *ifp;
312 	struct proc *p;
313 {
314 	register struct ifreq *ifr = (struct ifreq *)data;
315 	register struct in_ifaddr *ia = 0;
316 	struct in_aliasreq *ifra = (struct in_aliasreq *)data;
317 	struct sockaddr_in oldaddr;
318 	int error, hostIsNew, maskIsNew;
319 
320 #if NGIF > 0
321 	if (ifp && ifp->if_type == IFT_GIF) {
322 		switch (cmd) {
323 		case SIOCSIFPHYADDR:
324 			if (p == 0 || (error = suser(p->p_ucred, &p->p_acflag)))
325 				return(EPERM);
326 		case SIOCGIFPSRCADDR:
327 		case SIOCGIFPDSTADDR:
328 			return gif_ioctl(ifp, cmd, data);
329 		}
330 	}
331 #endif
332 
333 	switch (cmd) {
334 	case SIOCALIFADDR:
335 	case SIOCDLIFADDR:
336 		if (p == 0 || (error = suser(p->p_ucred, &p->p_acflag)))
337 			return(EPERM);
338 		/*fall through*/
339 	case SIOCGLIFADDR:
340 		if (!ifp)
341 			return EINVAL;
342 		return in_lifaddr_ioctl(so, cmd, data, ifp, p);
343 	}
344 
345 	/*
346 	 * Find address for this interface, if it exists.
347 	 */
348 	if (ifp)
349 		IFP_TO_IA(ifp, ia);
350 
351 	switch (cmd) {
352 
353 	case SIOCAIFADDR:
354 	case SIOCDIFADDR:
355 	case SIOCGIFALIAS:
356 		if (ifra->ifra_addr.sin_family == AF_INET)
357 			for (ia = IN_IFADDR_HASH(ifra->ifra_addr.sin_addr.s_addr).lh_first;
358 			    ia != 0; ia = ia->ia_hash.le_next) {
359 				if (ia->ia_ifp == ifp  &&
360 				    in_hosteq(ia->ia_addr.sin_addr,
361 				    ifra->ifra_addr.sin_addr))
362 					break;
363 			}
364 		if (cmd == SIOCDIFADDR && ia == 0)
365 			return (EADDRNOTAVAIL);
366 		/* FALLTHROUGH */
367 	case SIOCSIFADDR:
368 	case SIOCSIFNETMASK:
369 	case SIOCSIFDSTADDR:
370 		if (ifp == 0)
371 			panic("in_control");
372 
373 		if (cmd == SIOCGIFALIAS)
374 			break;
375 
376 		if (p == 0 || (error = suser(p->p_ucred, &p->p_acflag)))
377 			return (EPERM);
378 
379 		if (ia == 0) {
380 			MALLOC(ia, struct in_ifaddr *, sizeof(*ia),
381 			       M_IFADDR, M_WAITOK);
382 			if (ia == 0)
383 				return (ENOBUFS);
384 			bzero((caddr_t)ia, sizeof *ia);
385 			TAILQ_INSERT_TAIL(&in_ifaddr, ia, ia_list);
386 			TAILQ_INSERT_TAIL(&ifp->if_addrlist, (struct ifaddr *)ia,
387 			    ifa_list);
388 			ia->ia_ifa.ifa_addr = sintosa(&ia->ia_addr);
389 			ia->ia_ifa.ifa_dstaddr = sintosa(&ia->ia_dstaddr);
390 			ia->ia_ifa.ifa_netmask = sintosa(&ia->ia_sockmask);
391 			ia->ia_sockmask.sin_len = 8;
392 			if (ifp->if_flags & IFF_BROADCAST) {
393 				ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
394 				ia->ia_broadaddr.sin_family = AF_INET;
395 			}
396 			ia->ia_ifp = ifp;
397 			LIST_INIT(&ia->ia_multiaddrs);
398 			if ((ifp->if_flags & IFF_LOOPBACK) == 0)
399 				in_interfaces++;
400 		}
401 		break;
402 
403 	case SIOCSIFBRDADDR:
404 		if (p == 0 || (error = suser(p->p_ucred, &p->p_acflag)))
405 			return (EPERM);
406 		/* FALLTHROUGH */
407 
408 	case SIOCGIFADDR:
409 	case SIOCGIFNETMASK:
410 	case SIOCGIFDSTADDR:
411 	case SIOCGIFBRDADDR:
412 		if (ia == 0)
413 			return (EADDRNOTAVAIL);
414 		break;
415 	}
416 	switch (cmd) {
417 
418 	case SIOCGIFADDR:
419 		*satosin(&ifr->ifr_addr) = ia->ia_addr;
420 		break;
421 
422 	case SIOCGIFBRDADDR:
423 		if ((ifp->if_flags & IFF_BROADCAST) == 0)
424 			return (EINVAL);
425 		*satosin(&ifr->ifr_dstaddr) = ia->ia_broadaddr;
426 		break;
427 
428 	case SIOCGIFDSTADDR:
429 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
430 			return (EINVAL);
431 		*satosin(&ifr->ifr_dstaddr) = ia->ia_dstaddr;
432 		break;
433 
434 	case SIOCGIFNETMASK:
435 		*satosin(&ifr->ifr_addr) = ia->ia_sockmask;
436 		break;
437 
438 	case SIOCSIFDSTADDR:
439 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
440 			return (EINVAL);
441 		oldaddr = ia->ia_dstaddr;
442 		ia->ia_dstaddr = *satosin(&ifr->ifr_dstaddr);
443 		if (ifp->if_ioctl && (error = (*ifp->if_ioctl)
444 					(ifp, SIOCSIFDSTADDR, (caddr_t)ia))) {
445 			ia->ia_dstaddr = oldaddr;
446 			return (error);
447 		}
448 		if (ia->ia_flags & IFA_ROUTE) {
449 			ia->ia_ifa.ifa_dstaddr = sintosa(&oldaddr);
450 			rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
451 			ia->ia_ifa.ifa_dstaddr = sintosa(&ia->ia_dstaddr);
452 			rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP);
453 		}
454 		break;
455 
456 	case SIOCSIFBRDADDR:
457 		if ((ifp->if_flags & IFF_BROADCAST) == 0)
458 			return (EINVAL);
459 		ia->ia_broadaddr = *satosin(&ifr->ifr_broadaddr);
460 		break;
461 
462 	case SIOCSIFADDR:
463 		return (in_ifinit(ifp, ia, satosin(&ifr->ifr_addr), 1));
464 
465 	case SIOCSIFNETMASK:
466 		ia->ia_subnetmask = ia->ia_sockmask.sin_addr.s_addr =
467 		    ifra->ifra_addr.sin_addr.s_addr;
468 		break;
469 
470 	case SIOCAIFADDR:
471 		maskIsNew = 0;
472 		hostIsNew = 1;
473 		error = 0;
474 		if (ia->ia_addr.sin_family == AF_INET) {
475 			if (ifra->ifra_addr.sin_len == 0) {
476 				ifra->ifra_addr = ia->ia_addr;
477 				hostIsNew = 0;
478 			} else if (in_hosteq(ia->ia_addr.sin_addr, ifra->ifra_addr.sin_addr))
479 				hostIsNew = 0;
480 		}
481 		if (ifra->ifra_mask.sin_len) {
482 			in_ifscrub(ifp, ia);
483 			ia->ia_sockmask = ifra->ifra_mask;
484 			ia->ia_subnetmask = ia->ia_sockmask.sin_addr.s_addr;
485 			maskIsNew = 1;
486 		}
487 		if ((ifp->if_flags & IFF_POINTOPOINT) &&
488 		    (ifra->ifra_dstaddr.sin_family == AF_INET)) {
489 			in_ifscrub(ifp, ia);
490 			ia->ia_dstaddr = ifra->ifra_dstaddr;
491 			maskIsNew  = 1; /* We lie; but the effect's the same */
492 		}
493 		if (ifra->ifra_addr.sin_family == AF_INET &&
494 		    (hostIsNew || maskIsNew))
495 			error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
496 		if ((ifp->if_flags & IFF_BROADCAST) &&
497 		    (ifra->ifra_broadaddr.sin_family == AF_INET))
498 			ia->ia_broadaddr = ifra->ifra_broadaddr;
499 		return (error);
500 
501 	case SIOCGIFALIAS:
502 		ifra->ifra_mask = ia->ia_sockmask;
503 		if ((ifp->if_flags & IFF_POINTOPOINT) &&
504 		    (ia->ia_dstaddr.sin_family == AF_INET))
505 			ifra->ifra_dstaddr = ia->ia_dstaddr;
506 		else if ((ifp->if_flags & IFF_BROADCAST) &&
507 		    (ia->ia_broadaddr.sin_family == AF_INET))
508 			ifra->ifra_broadaddr = ia->ia_broadaddr;
509 		else
510 			bzero(&ifra->ifra_broadaddr,
511 			      sizeof(ifra->ifra_broadaddr));
512 		return 0;
513 
514 	case SIOCDIFADDR:
515 		in_ifscrub(ifp, ia);
516 		LIST_REMOVE(ia, ia_hash);
517 		TAILQ_REMOVE(&ifp->if_addrlist, (struct ifaddr *)ia, ifa_list);
518 		TAILQ_REMOVE(&in_ifaddr, ia, ia_list);
519 		IFAFREE((&ia->ia_ifa));
520 		in_setmaxmtu();
521 		break;
522 
523 #ifdef MROUTING
524 	case SIOCGETVIFCNT:
525 	case SIOCGETSGCNT:
526 		return (mrt_ioctl(so, cmd, data));
527 #endif /* MROUTING */
528 
529 	default:
530 		if (ifp == 0 || ifp->if_ioctl == 0)
531 			return (EOPNOTSUPP);
532 		error = (*ifp->if_ioctl)(ifp, cmd, data);
533 		in_setmaxmtu();
534 		return(error);
535 	}
536 	return (0);
537 }
538 
539 /*
540  * SIOC[GAD]LIFADDR.
541  *	SIOCGLIFADDR: get first address. (???)
542  *	SIOCGLIFADDR with IFLR_PREFIX:
543  *		get first address that matches the specified prefix.
544  *	SIOCALIFADDR: add the specified address.
545  *	SIOCALIFADDR with IFLR_PREFIX:
546  *		EINVAL since we can't deduce hostid part of the address.
547  *	SIOCDLIFADDR: delete the specified address.
548  *	SIOCDLIFADDR with IFLR_PREFIX:
549  *		delete the first address that matches the specified prefix.
550  * return values:
551  *	EINVAL on invalid parameters
552  *	EADDRNOTAVAIL on prefix match failed/specified address not found
553  *	other values may be returned from in_ioctl()
554  */
555 static int
556 in_lifaddr_ioctl(so, cmd, data, ifp, p)
557 	struct socket *so;
558 	u_long cmd;
559 	caddr_t	data;
560 	struct ifnet *ifp;
561 	struct proc *p;
562 {
563 	struct if_laddrreq *iflr = (struct if_laddrreq *)data;
564 	struct ifaddr *ifa;
565 	struct sockaddr *sa;
566 
567 	/* sanity checks */
568 	if (!data || !ifp) {
569 		panic("invalid argument to in_lifaddr_ioctl");
570 		/*NOTRECHED*/
571 	}
572 
573 	switch (cmd) {
574 	case SIOCGLIFADDR:
575 		/* address must be specified on GET with IFLR_PREFIX */
576 		if ((iflr->flags & IFLR_PREFIX) == 0)
577 			break;
578 		/*FALLTHROUGH*/
579 	case SIOCALIFADDR:
580 	case SIOCDLIFADDR:
581 		/* address must be specified on ADD and DELETE */
582 		sa = (struct sockaddr *)&iflr->addr;
583 		if (sa->sa_family != AF_INET)
584 			return EINVAL;
585 		if (sa->sa_len != sizeof(struct sockaddr_in))
586 			return EINVAL;
587 		/* XXX need improvement */
588 		sa = (struct sockaddr *)&iflr->dstaddr;
589 		if (sa->sa_family
590 		 && sa->sa_family != AF_INET)
591 			return EINVAL;
592 		if (sa->sa_len && sa->sa_len != sizeof(struct sockaddr_in))
593 			return EINVAL;
594 		break;
595 	default: /*shouldn't happen*/
596 #if 0
597 		panic("invalid cmd to in_lifaddr_ioctl");
598 		/*NOTREACHED*/
599 #else
600 		return EOPNOTSUPP;
601 #endif
602 	}
603 	if (sizeof(struct in_addr) * 8 < iflr->prefixlen)
604 		return EINVAL;
605 
606 	switch (cmd) {
607 	case SIOCALIFADDR:
608 	    {
609 		struct in_aliasreq ifra;
610 
611 		if (iflr->flags & IFLR_PREFIX)
612 			return EINVAL;
613 
614 		/* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
615 		bzero(&ifra, sizeof(ifra));
616 		bcopy(iflr->iflr_name, ifra.ifra_name,
617 			sizeof(ifra.ifra_name));
618 
619 		bcopy(&iflr->addr, &ifra.ifra_addr,
620 			((struct sockaddr *)&iflr->addr)->sa_len);
621 
622 		if (((struct sockaddr *)&iflr->dstaddr)->sa_family) {	/*XXX*/
623 			bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
624 				((struct sockaddr *)&iflr->dstaddr)->sa_len);
625 		}
626 
627 		ifra.ifra_mask.sin_family = AF_INET;
628 		ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
629 		in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);
630 
631 		return in_control(so, SIOCAIFADDR, (caddr_t)&ifra, ifp, p);
632 	    }
633 	case SIOCGLIFADDR:
634 	case SIOCDLIFADDR:
635 	    {
636 		struct in_ifaddr *ia;
637 		struct in_addr mask, candidate, match;
638 		struct sockaddr_in *sin;
639 		int cmp;
640 
641 		bzero(&mask, sizeof(mask));
642 		if (iflr->flags & IFLR_PREFIX) {
643 			/* lookup a prefix rather than address. */
644 			in_len2mask(&mask, iflr->prefixlen);
645 
646 			sin = (struct sockaddr_in *)&iflr->addr;
647 			match.s_addr = sin->sin_addr.s_addr;
648 			match.s_addr &= mask.s_addr;
649 
650 			/* if you set extra bits, that's wrong */
651 			if (match.s_addr != sin->sin_addr.s_addr)
652 				return EINVAL;
653 
654 			cmp = 1;
655 		} else {
656 			if (cmd == SIOCGLIFADDR) {
657 				/* on getting an address, take the 1st match */
658 				cmp = 0;	/*XXX*/
659 			} else {
660 				/* on deleting an address, do exact match */
661 				in_len2mask(&mask, 32);
662 				sin = (struct sockaddr_in *)&iflr->addr;
663 				match.s_addr = sin->sin_addr.s_addr;
664 
665 				cmp = 1;
666 			}
667 		}
668 
669 		for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next) {
670 			if (ifa->ifa_addr->sa_family != AF_INET6)
671 				continue;
672 			if (!cmp)
673 				break;
674 			candidate.s_addr = ((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr;
675 			candidate.s_addr &= mask.s_addr;
676 			if (candidate.s_addr == match.s_addr)
677 				break;
678 		}
679 		if (!ifa)
680 			return EADDRNOTAVAIL;
681 		ia = (struct in_ifaddr *)ifa;
682 
683 		if (cmd == SIOCGLIFADDR) {
684 			/* fill in the if_laddrreq structure */
685 			bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len);
686 
687 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
688 				bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
689 					ia->ia_dstaddr.sin_len);
690 			} else
691 				bzero(&iflr->dstaddr, sizeof(iflr->dstaddr));
692 
693 			iflr->prefixlen =
694 				in_mask2len(&ia->ia_sockmask.sin_addr);
695 
696 			iflr->flags = 0;	/*XXX*/
697 
698 			return 0;
699 		} else {
700 			struct in_aliasreq ifra;
701 
702 			/* fill in_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
703 			bzero(&ifra, sizeof(ifra));
704 			bcopy(iflr->iflr_name, ifra.ifra_name,
705 				sizeof(ifra.ifra_name));
706 
707 			bcopy(&ia->ia_addr, &ifra.ifra_addr,
708 				ia->ia_addr.sin_len);
709 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
710 				bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
711 					ia->ia_dstaddr.sin_len);
712 			}
713 			bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr,
714 				ia->ia_sockmask.sin_len);
715 
716 			return in_control(so, SIOCDIFADDR, (caddr_t)&ifra,
717 				ifp, p);
718 		}
719 	    }
720 	}
721 
722 	return EOPNOTSUPP;	/*just for safety*/
723 }
724 
725 /*
726  * Delete any existing route for an interface.
727  */
728 void
729 in_ifscrub(ifp, ia)
730 	register struct ifnet *ifp;
731 	register struct in_ifaddr *ia;
732 {
733 
734 	if ((ia->ia_flags & IFA_ROUTE) == 0)
735 		return;
736 	if (ifp->if_flags & (IFF_LOOPBACK|IFF_POINTOPOINT))
737 		rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
738 	else
739 		rtinit(&(ia->ia_ifa), (int)RTM_DELETE, 0);
740 	ia->ia_flags &= ~IFA_ROUTE;
741 }
742 
743 /*
744  * Initialize an interface's internet address
745  * and routing table entry.
746  */
747 int
748 in_ifinit(ifp, ia, sin, scrub)
749 	register struct ifnet *ifp;
750 	register struct in_ifaddr *ia;
751 	struct sockaddr_in *sin;
752 	int scrub;
753 {
754 	register u_int32_t i = sin->sin_addr.s_addr;
755 	struct sockaddr_in oldaddr;
756 	int s = splimp(), flags = RTF_UP, error;
757 
758 	/*
759 	 * Set up new addresses.
760 	 */
761 	oldaddr = ia->ia_addr;
762 	if (ia->ia_addr.sin_family == AF_INET)
763 		LIST_REMOVE(ia, ia_hash);
764 	ia->ia_addr = *sin;
765 	LIST_INSERT_HEAD(&IN_IFADDR_HASH(ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
766 
767 	/*
768 	 * Give the interface a chance to initialize
769 	 * if this is its first address,
770 	 * and to validate the address if necessary.
771 	 */
772 	if (ifp->if_ioctl &&
773 	    (error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia)))
774 		goto bad;
775 	splx(s);
776 	if (scrub) {
777 		ia->ia_ifa.ifa_addr = sintosa(&oldaddr);
778 		in_ifscrub(ifp, ia);
779 		ia->ia_ifa.ifa_addr = sintosa(&ia->ia_addr);
780 	}
781 
782 	if (IN_CLASSA(i))
783 		ia->ia_netmask = IN_CLASSA_NET;
784 	else if (IN_CLASSB(i))
785 		ia->ia_netmask = IN_CLASSB_NET;
786 	else
787 		ia->ia_netmask = IN_CLASSC_NET;
788 	/*
789 	 * The subnet mask usually includes at least the standard network part,
790 	 * but may may be smaller in the case of supernetting.
791 	 * If it is set, we believe it.
792 	 */
793 	if (ia->ia_subnetmask == 0) {
794 		ia->ia_subnetmask = ia->ia_netmask;
795 		ia->ia_sockmask.sin_addr.s_addr = ia->ia_subnetmask;
796 	} else
797 		ia->ia_netmask &= ia->ia_subnetmask;
798 
799 	ia->ia_net = i & ia->ia_netmask;
800 	ia->ia_subnet = i & ia->ia_subnetmask;
801 	in_socktrim(&ia->ia_sockmask);
802 	/* re-calculate the "in_maxmtu" value */
803 	in_setmaxmtu();
804 	/*
805 	 * Add route for the network.
806 	 */
807 	ia->ia_ifa.ifa_metric = ifp->if_metric;
808 	if (ifp->if_flags & IFF_BROADCAST) {
809 		ia->ia_broadaddr.sin_addr.s_addr =
810 			ia->ia_subnet | ~ia->ia_subnetmask;
811 		ia->ia_netbroadcast.s_addr =
812 			ia->ia_net | ~ia->ia_netmask;
813 	} else if (ifp->if_flags & IFF_LOOPBACK) {
814 		ia->ia_ifa.ifa_dstaddr = ia->ia_ifa.ifa_addr;
815 		flags |= RTF_HOST;
816 	} else if (ifp->if_flags & IFF_POINTOPOINT) {
817 		if (ia->ia_dstaddr.sin_family != AF_INET)
818 			return (0);
819 		flags |= RTF_HOST;
820 	}
821 	error = rtinit(&ia->ia_ifa, (int)RTM_ADD, flags);
822 	if (!error)
823 		ia->ia_flags |= IFA_ROUTE;
824 	/*
825 	 * If the interface supports multicast, join the "all hosts"
826 	 * multicast group on that interface.
827 	 */
828 	if (ifp->if_flags & IFF_MULTICAST) {
829 		struct in_addr addr;
830 
831 		addr.s_addr = INADDR_ALLHOSTS_GROUP;
832 		in_addmulti(&addr, ifp);
833 	}
834 	return (error);
835 bad:
836 	splx(s);
837 	LIST_REMOVE(ia, ia_hash);
838 	ia->ia_addr = oldaddr;
839 	if (ia->ia_addr.sin_family == AF_INET)
840 		LIST_INSERT_HEAD(&IN_IFADDR_HASH(ia->ia_addr.sin_addr.s_addr),
841 		    ia, ia_hash);
842 	return (error);
843 }
844 
845 /*
846  * Return 1 if the address might be a local broadcast address.
847  */
848 int
849 in_broadcast(in, ifp)
850 	struct in_addr in;
851 	struct ifnet *ifp;
852 {
853 	register struct ifaddr *ifa;
854 
855 	if (in.s_addr == INADDR_BROADCAST ||
856 	    in_nullhost(in))
857 		return 1;
858 	if ((ifp->if_flags & IFF_BROADCAST) == 0)
859 		return 0;
860 	/*
861 	 * Look through the list of addresses for a match
862 	 * with a broadcast address.
863 	 */
864 #define ia (ifatoia(ifa))
865 	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
866 		if (ifa->ifa_addr->sa_family == AF_INET &&
867 		    (in_hosteq(in, ia->ia_broadaddr.sin_addr) ||
868 		     in_hosteq(in, ia->ia_netbroadcast) ||
869 		     (hostzeroisbroadcast &&
870 		      /*
871 		       * Check for old-style (host 0) broadcast.
872 		       */
873 		      (in.s_addr == ia->ia_subnet ||
874 		       in.s_addr == ia->ia_net))))
875 			return 1;
876 	return (0);
877 #undef ia
878 }
879 
880 /*
881  * Add an address to the list of IP multicast addresses for a given interface.
882  */
883 struct in_multi *
884 in_addmulti(ap, ifp)
885 	register struct in_addr *ap;
886 	register struct ifnet *ifp;
887 {
888 	register struct in_multi *inm;
889 	struct ifreq ifr;
890 	struct in_ifaddr *ia;
891 	int s = splsoftnet();
892 
893 	/*
894 	 * See if address already in list.
895 	 */
896 	IN_LOOKUP_MULTI(*ap, ifp, inm);
897 	if (inm != NULL) {
898 		/*
899 		 * Found it; just increment the reference count.
900 		 */
901 		++inm->inm_refcount;
902 	} else {
903 		/*
904 		 * New address; allocate a new multicast record
905 		 * and link it into the interface's multicast list.
906 		 */
907 		inm = (struct in_multi *)malloc(sizeof(*inm),
908 		    M_IPMADDR, M_NOWAIT);
909 		if (inm == NULL) {
910 			splx(s);
911 			return (NULL);
912 		}
913 		inm->inm_addr = *ap;
914 		inm->inm_ifp = ifp;
915 		inm->inm_refcount = 1;
916 		IFP_TO_IA(ifp, ia);
917 		if (ia == NULL) {
918 			free(inm, M_IPMADDR);
919 			splx(s);
920 			return (NULL);
921 		}
922 		inm->inm_ia = ia;
923 		LIST_INSERT_HEAD(&ia->ia_multiaddrs, inm, inm_list);
924 		/*
925 		 * Ask the network driver to update its multicast reception
926 		 * filter appropriately for the new address.
927 		 */
928 		satosin(&ifr.ifr_addr)->sin_len = sizeof(struct sockaddr_in);
929 		satosin(&ifr.ifr_addr)->sin_family = AF_INET;
930 		satosin(&ifr.ifr_addr)->sin_addr = *ap;
931 		if ((ifp->if_ioctl == NULL) ||
932 		    (*ifp->if_ioctl)(ifp, SIOCADDMULTI,(caddr_t)&ifr) != 0) {
933 			LIST_REMOVE(inm, inm_list);
934 			free(inm, M_IPMADDR);
935 			splx(s);
936 			return (NULL);
937 		}
938 		/*
939 		 * Let IGMP know that we have joined a new IP multicast group.
940 		 */
941 		igmp_joingroup(inm);
942 	}
943 	splx(s);
944 	return (inm);
945 }
946 
947 /*
948  * Delete a multicast address record.
949  */
950 void
951 in_delmulti(inm)
952 	register struct in_multi *inm;
953 {
954 	struct ifreq ifr;
955 	int s = splsoftnet();
956 
957 	if (--inm->inm_refcount == 0) {
958 		/*
959 		 * No remaining claims to this record; let IGMP know that
960 		 * we are leaving the multicast group.
961 		 */
962 		igmp_leavegroup(inm);
963 		/*
964 		 * Unlink from list.
965 		 */
966 		LIST_REMOVE(inm, inm_list);
967 		/*
968 		 * Notify the network driver to update its multicast reception
969 		 * filter.
970 		 */
971 		satosin(&ifr.ifr_addr)->sin_family = AF_INET;
972 		satosin(&ifr.ifr_addr)->sin_addr = inm->inm_addr;
973 		(*inm->inm_ifp->if_ioctl)(inm->inm_ifp, SIOCDELMULTI,
974 							     (caddr_t)&ifr);
975 		free(inm, M_IPMADDR);
976 	}
977 	splx(s);
978 }
979 #endif
980