xref: /netbsd-src/sys/netinet/in.c (revision 481fca6e59249d8ffcf24fef7cfbe7b131bfb080)
1 /*	$NetBSD: in.c,v 1.61 2000/05/06 02:41:32 mycroft 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 	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 	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 	char *cplim = (char *) &ap->sin_addr;
205 	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 	struct in_ifaddr *ia;
246 	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 /*
300  * Generic internet control operations (ioctl's).
301  * Ifp is 0 if not an interface-specific ioctl.
302  */
303 /* ARGSUSED */
304 int
305 in_control(so, cmd, data, ifp, p)
306 	struct socket *so;
307 	u_long cmd;
308 	caddr_t data;
309 	struct ifnet *ifp;
310 	struct proc *p;
311 {
312 	struct ifreq *ifr = (struct ifreq *)data;
313 	struct in_ifaddr *ia = 0;
314 	struct in_aliasreq *ifra = (struct in_aliasreq *)data;
315 	struct sockaddr_in oldaddr;
316 	int error, hostIsNew, maskIsNew;
317 	int newifaddr;
318 
319 #if NGIF > 0
320 	if (ifp && ifp->if_type == IFT_GIF) {
321 		switch (cmd) {
322 		case SIOCSIFPHYADDR:
323 			if (p == 0 || (error = suser(p->p_ucred, &p->p_acflag)))
324 				return(EPERM);
325 		case SIOCGIFPSRCADDR:
326 		case SIOCGIFPDSTADDR:
327 			return gif_ioctl(ifp, cmd, data);
328 		}
329 	}
330 #endif
331 
332 	switch (cmd) {
333 	case SIOCALIFADDR:
334 	case SIOCDLIFADDR:
335 		if (p == 0 || (error = suser(p->p_ucred, &p->p_acflag)))
336 			return(EPERM);
337 		/*fall through*/
338 	case SIOCGLIFADDR:
339 		if (!ifp)
340 			return EINVAL;
341 		return in_lifaddr_ioctl(so, cmd, data, ifp, p);
342 	}
343 
344 	/*
345 	 * Find address for this interface, if it exists.
346 	 */
347 	if (ifp)
348 		IFP_TO_IA(ifp, ia);
349 
350 	switch (cmd) {
351 
352 	case SIOCAIFADDR:
353 	case SIOCDIFADDR:
354 	case SIOCGIFALIAS:
355 		if (ifra->ifra_addr.sin_family == AF_INET)
356 			for (ia = IN_IFADDR_HASH(ifra->ifra_addr.sin_addr.s_addr).lh_first;
357 			    ia != 0; ia = ia->ia_hash.le_next) {
358 				if (ia->ia_ifp == ifp  &&
359 				    in_hosteq(ia->ia_addr.sin_addr,
360 				    ifra->ifra_addr.sin_addr))
361 					break;
362 			}
363 		if (cmd == SIOCDIFADDR) {
364 			if (ia == 0)
365 				return (EADDRNOTAVAIL);
366 #if 1 /*def COMPAT_43*/
367 			if (ifra->ifra_addr.sin_family == AF_UNSPEC)
368 				ifra->ifra_addr.sin_family = AF_INET;
369 #endif
370 		}
371 		/* FALLTHROUGH */
372 	case SIOCSIFADDR:
373 	case SIOCSIFDSTADDR:
374 		if (ifra->ifra_addr.sin_family != AF_INET)
375 			return (EAFNOSUPPORT);
376 		/* FALLTHROUGH */
377 	case SIOCSIFNETMASK:
378 		if (ifp == 0)
379 			panic("in_control");
380 
381 		if (cmd == SIOCGIFALIAS)
382 			break;
383 
384 		if (p == 0 || (error = suser(p->p_ucred, &p->p_acflag)))
385 			return (EPERM);
386 
387 		if (ia == 0) {
388 			MALLOC(ia, struct in_ifaddr *, sizeof(*ia),
389 			       M_IFADDR, M_WAITOK);
390 			if (ia == 0)
391 				return (ENOBUFS);
392 			bzero((caddr_t)ia, sizeof *ia);
393 			TAILQ_INSERT_TAIL(&in_ifaddr, ia, ia_list);
394 			IFAREF(&ia->ia_ifa);
395 			TAILQ_INSERT_TAIL(&ifp->if_addrlist, &ia->ia_ifa,
396 			    ifa_list);
397 			IFAREF(&ia->ia_ifa);
398 			ia->ia_ifa.ifa_addr = sintosa(&ia->ia_addr);
399 			ia->ia_ifa.ifa_dstaddr = sintosa(&ia->ia_dstaddr);
400 			ia->ia_ifa.ifa_netmask = sintosa(&ia->ia_sockmask);
401 			ia->ia_sockmask.sin_len = 8;
402 			if (ifp->if_flags & IFF_BROADCAST) {
403 				ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
404 				ia->ia_broadaddr.sin_family = AF_INET;
405 			}
406 			ia->ia_ifp = ifp;
407 			LIST_INIT(&ia->ia_multiaddrs);
408 			newifaddr = 1;
409 		} else
410 			newifaddr = 0;
411 		break;
412 
413 	case SIOCSIFBRDADDR:
414 		if (p == 0 || (error = suser(p->p_ucred, &p->p_acflag)))
415 			return (EPERM);
416 		/* FALLTHROUGH */
417 
418 	case SIOCGIFADDR:
419 	case SIOCGIFNETMASK:
420 	case SIOCGIFDSTADDR:
421 	case SIOCGIFBRDADDR:
422 		if (ia == 0)
423 			return (EADDRNOTAVAIL);
424 		break;
425 	}
426 	switch (cmd) {
427 
428 	case SIOCGIFADDR:
429 		*satosin(&ifr->ifr_addr) = ia->ia_addr;
430 		break;
431 
432 	case SIOCGIFBRDADDR:
433 		if ((ifp->if_flags & IFF_BROADCAST) == 0)
434 			return (EINVAL);
435 		*satosin(&ifr->ifr_dstaddr) = ia->ia_broadaddr;
436 		break;
437 
438 	case SIOCGIFDSTADDR:
439 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
440 			return (EINVAL);
441 		*satosin(&ifr->ifr_dstaddr) = ia->ia_dstaddr;
442 		break;
443 
444 	case SIOCGIFNETMASK:
445 		*satosin(&ifr->ifr_addr) = ia->ia_sockmask;
446 		break;
447 
448 	case SIOCSIFDSTADDR:
449 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
450 			return (EINVAL);
451 		oldaddr = ia->ia_dstaddr;
452 		ia->ia_dstaddr = *satosin(&ifr->ifr_dstaddr);
453 		if (ifp->if_ioctl && (error = (*ifp->if_ioctl)
454 					(ifp, SIOCSIFDSTADDR, (caddr_t)ia))) {
455 			ia->ia_dstaddr = oldaddr;
456 			return (error);
457 		}
458 		if (ia->ia_flags & IFA_ROUTE) {
459 			ia->ia_ifa.ifa_dstaddr = sintosa(&oldaddr);
460 			rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
461 			ia->ia_ifa.ifa_dstaddr = sintosa(&ia->ia_dstaddr);
462 			rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP);
463 		}
464 		break;
465 
466 	case SIOCSIFBRDADDR:
467 		if ((ifp->if_flags & IFF_BROADCAST) == 0)
468 			return (EINVAL);
469 		ia->ia_broadaddr = *satosin(&ifr->ifr_broadaddr);
470 		break;
471 
472 	case SIOCSIFADDR:
473 		error = in_ifinit(ifp, ia, satosin(&ifr->ifr_addr), 1);
474 #if 0
475 		/*
476 		 * the code chokes if we are to assign multiple addresses with
477 		 * the same address prefix (rtinit() will return EEXIST, which
478 		 * is not fatal actually).  we will get memory leak if we
479 		 * don't do it.
480 		 * -> we may want to hide EEXIST from rtinit().
481 		 */
482   undo:
483 		if (error && newifaddr) {
484 			TAILQ_REMOVE(&ifp->if_addrlist, &ia->ia_ifa, ifa_list);
485 			IFAFREE(&ia->ia_ifa);
486 			TAILQ_REMOVE(&in_ifaddr, ia, ia_list);
487 			IFAFREE(&ia->ia_ifa);
488 		}
489 #endif
490 		return error;
491 
492 	case SIOCSIFNETMASK:
493 		ia->ia_subnetmask = ia->ia_sockmask.sin_addr.s_addr =
494 		    ifra->ifra_addr.sin_addr.s_addr;
495 		break;
496 
497 	case SIOCAIFADDR:
498 		maskIsNew = 0;
499 		hostIsNew = 1;
500 		error = 0;
501 		if (ia->ia_addr.sin_family == AF_INET) {
502 			if (ifra->ifra_addr.sin_len == 0) {
503 				ifra->ifra_addr = ia->ia_addr;
504 				hostIsNew = 0;
505 			} else if (in_hosteq(ia->ia_addr.sin_addr, ifra->ifra_addr.sin_addr))
506 				hostIsNew = 0;
507 		}
508 		if (ifra->ifra_mask.sin_len) {
509 			in_ifscrub(ifp, ia);
510 			ia->ia_sockmask = ifra->ifra_mask;
511 			ia->ia_subnetmask = ia->ia_sockmask.sin_addr.s_addr;
512 			maskIsNew = 1;
513 		}
514 		if ((ifp->if_flags & IFF_POINTOPOINT) &&
515 		    (ifra->ifra_dstaddr.sin_family == AF_INET)) {
516 			in_ifscrub(ifp, ia);
517 			ia->ia_dstaddr = ifra->ifra_dstaddr;
518 			maskIsNew  = 1; /* We lie; but the effect's the same */
519 		}
520 		if (ifra->ifra_addr.sin_family == AF_INET &&
521 		    (hostIsNew || maskIsNew)) {
522 			error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
523 #if 0
524 			if (error)
525 				goto undo;
526 #endif
527 		}
528 		if ((ifp->if_flags & IFF_BROADCAST) &&
529 		    (ifra->ifra_broadaddr.sin_family == AF_INET))
530 			ia->ia_broadaddr = ifra->ifra_broadaddr;
531 		return (error);
532 
533 	case SIOCGIFALIAS:
534 		ifra->ifra_mask = ia->ia_sockmask;
535 		if ((ifp->if_flags & IFF_POINTOPOINT) &&
536 		    (ia->ia_dstaddr.sin_family == AF_INET))
537 			ifra->ifra_dstaddr = ia->ia_dstaddr;
538 		else if ((ifp->if_flags & IFF_BROADCAST) &&
539 		    (ia->ia_broadaddr.sin_family == AF_INET))
540 			ifra->ifra_broadaddr = ia->ia_broadaddr;
541 		else
542 			bzero(&ifra->ifra_broadaddr,
543 			      sizeof(ifra->ifra_broadaddr));
544 		return 0;
545 
546 	case SIOCDIFADDR:
547 		in_purgeaddr(&ia->ia_ifa, ifp);
548 		break;
549 
550 #ifdef MROUTING
551 	case SIOCGETVIFCNT:
552 	case SIOCGETSGCNT:
553 		return (mrt_ioctl(so, cmd, data));
554 #endif /* MROUTING */
555 
556 	default:
557 		if (ifp == 0 || ifp->if_ioctl == 0)
558 			return (EOPNOTSUPP);
559 		error = (*ifp->if_ioctl)(ifp, cmd, data);
560 		in_setmaxmtu();
561 		return(error);
562 	}
563 	return (0);
564 }
565 
566 void
567 in_purgeaddr(ifa, ifp)
568 	struct ifaddr *ifa;
569 	struct ifnet *ifp;
570 {
571 	struct in_ifaddr *ia = (void *) ifa;
572 
573 	in_ifscrub(ifp, ia);
574 	LIST_REMOVE(ia, ia_hash);
575 	TAILQ_REMOVE(&ifp->if_addrlist, &ia->ia_ifa, ifa_list);
576 	IFAFREE(&ia->ia_ifa);
577 	TAILQ_REMOVE(&in_ifaddr, ia, ia_list);
578 	IFAFREE(&ia->ia_ifa);
579 	in_setmaxmtu();
580 }
581 
582 void
583 in_purgeif(ifp)
584 	struct ifnet *ifp;
585 {
586 	struct ifaddr *ifa, *nifa;
587 
588 	for (ifa = TAILQ_FIRST(&ifp->if_addrlist); ifa != NULL; ifa = nifa) {
589 		nifa = TAILQ_NEXT(ifa, ifa_list);
590 		if (ifa->ifa_addr->sa_family != AF_INET)
591 			continue;
592 		in_purgeaddr(ifa, ifp);
593 	}
594 }
595 
596 /*
597  * SIOC[GAD]LIFADDR.
598  *	SIOCGLIFADDR: get first address. (???)
599  *	SIOCGLIFADDR with IFLR_PREFIX:
600  *		get first address that matches the specified prefix.
601  *	SIOCALIFADDR: add the specified address.
602  *	SIOCALIFADDR with IFLR_PREFIX:
603  *		EINVAL since we can't deduce hostid part of the address.
604  *	SIOCDLIFADDR: delete the specified address.
605  *	SIOCDLIFADDR with IFLR_PREFIX:
606  *		delete the first address that matches the specified prefix.
607  * return values:
608  *	EINVAL on invalid parameters
609  *	EADDRNOTAVAIL on prefix match failed/specified address not found
610  *	other values may be returned from in_ioctl()
611  */
612 static int
613 in_lifaddr_ioctl(so, cmd, data, ifp, p)
614 	struct socket *so;
615 	u_long cmd;
616 	caddr_t	data;
617 	struct ifnet *ifp;
618 	struct proc *p;
619 {
620 	struct if_laddrreq *iflr = (struct if_laddrreq *)data;
621 	struct ifaddr *ifa;
622 	struct sockaddr *sa;
623 
624 	/* sanity checks */
625 	if (!data || !ifp) {
626 		panic("invalid argument to in_lifaddr_ioctl");
627 		/*NOTRECHED*/
628 	}
629 
630 	switch (cmd) {
631 	case SIOCGLIFADDR:
632 		/* address must be specified on GET with IFLR_PREFIX */
633 		if ((iflr->flags & IFLR_PREFIX) == 0)
634 			break;
635 		/*FALLTHROUGH*/
636 	case SIOCALIFADDR:
637 	case SIOCDLIFADDR:
638 		/* address must be specified on ADD and DELETE */
639 		sa = (struct sockaddr *)&iflr->addr;
640 		if (sa->sa_family != AF_INET)
641 			return EINVAL;
642 		if (sa->sa_len != sizeof(struct sockaddr_in))
643 			return EINVAL;
644 		/* XXX need improvement */
645 		sa = (struct sockaddr *)&iflr->dstaddr;
646 		if (sa->sa_family
647 		 && sa->sa_family != AF_INET)
648 			return EINVAL;
649 		if (sa->sa_len && sa->sa_len != sizeof(struct sockaddr_in))
650 			return EINVAL;
651 		break;
652 	default: /*shouldn't happen*/
653 #if 0
654 		panic("invalid cmd to in_lifaddr_ioctl");
655 		/*NOTREACHED*/
656 #else
657 		return EOPNOTSUPP;
658 #endif
659 	}
660 	if (sizeof(struct in_addr) * 8 < iflr->prefixlen)
661 		return EINVAL;
662 
663 	switch (cmd) {
664 	case SIOCALIFADDR:
665 	    {
666 		struct in_aliasreq ifra;
667 
668 		if (iflr->flags & IFLR_PREFIX)
669 			return EINVAL;
670 
671 		/* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
672 		bzero(&ifra, sizeof(ifra));
673 		bcopy(iflr->iflr_name, ifra.ifra_name,
674 			sizeof(ifra.ifra_name));
675 
676 		bcopy(&iflr->addr, &ifra.ifra_addr,
677 			((struct sockaddr *)&iflr->addr)->sa_len);
678 
679 		if (((struct sockaddr *)&iflr->dstaddr)->sa_family) {	/*XXX*/
680 			bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
681 				((struct sockaddr *)&iflr->dstaddr)->sa_len);
682 		}
683 
684 		ifra.ifra_mask.sin_family = AF_INET;
685 		ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
686 		in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);
687 
688 		return in_control(so, SIOCAIFADDR, (caddr_t)&ifra, ifp, p);
689 	    }
690 	case SIOCGLIFADDR:
691 	case SIOCDLIFADDR:
692 	    {
693 		struct in_ifaddr *ia;
694 		struct in_addr mask, candidate, match;
695 		struct sockaddr_in *sin;
696 		int cmp;
697 
698 		bzero(&mask, sizeof(mask));
699 		if (iflr->flags & IFLR_PREFIX) {
700 			/* lookup a prefix rather than address. */
701 			in_len2mask(&mask, iflr->prefixlen);
702 
703 			sin = (struct sockaddr_in *)&iflr->addr;
704 			match.s_addr = sin->sin_addr.s_addr;
705 			match.s_addr &= mask.s_addr;
706 
707 			/* if you set extra bits, that's wrong */
708 			if (match.s_addr != sin->sin_addr.s_addr)
709 				return EINVAL;
710 
711 			cmp = 1;
712 		} else {
713 			if (cmd == SIOCGLIFADDR) {
714 				/* on getting an address, take the 1st match */
715 				cmp = 0;	/*XXX*/
716 			} else {
717 				/* on deleting an address, do exact match */
718 				in_len2mask(&mask, 32);
719 				sin = (struct sockaddr_in *)&iflr->addr;
720 				match.s_addr = sin->sin_addr.s_addr;
721 
722 				cmp = 1;
723 			}
724 		}
725 
726 		for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next) {
727 			if (ifa->ifa_addr->sa_family != AF_INET6)
728 				continue;
729 			if (!cmp)
730 				break;
731 			candidate.s_addr = ((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr;
732 			candidate.s_addr &= mask.s_addr;
733 			if (candidate.s_addr == match.s_addr)
734 				break;
735 		}
736 		if (!ifa)
737 			return EADDRNOTAVAIL;
738 		ia = (struct in_ifaddr *)ifa;
739 
740 		if (cmd == SIOCGLIFADDR) {
741 			/* fill in the if_laddrreq structure */
742 			bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len);
743 
744 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
745 				bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
746 					ia->ia_dstaddr.sin_len);
747 			} else
748 				bzero(&iflr->dstaddr, sizeof(iflr->dstaddr));
749 
750 			iflr->prefixlen =
751 				in_mask2len(&ia->ia_sockmask.sin_addr);
752 
753 			iflr->flags = 0;	/*XXX*/
754 
755 			return 0;
756 		} else {
757 			struct in_aliasreq ifra;
758 
759 			/* fill in_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
760 			bzero(&ifra, sizeof(ifra));
761 			bcopy(iflr->iflr_name, ifra.ifra_name,
762 				sizeof(ifra.ifra_name));
763 
764 			bcopy(&ia->ia_addr, &ifra.ifra_addr,
765 				ia->ia_addr.sin_len);
766 			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
767 				bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
768 					ia->ia_dstaddr.sin_len);
769 			}
770 			bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr,
771 				ia->ia_sockmask.sin_len);
772 
773 			return in_control(so, SIOCDIFADDR, (caddr_t)&ifra,
774 				ifp, p);
775 		}
776 	    }
777 	}
778 
779 	return EOPNOTSUPP;	/*just for safety*/
780 }
781 
782 /*
783  * Delete any existing route for an interface.
784  */
785 void
786 in_ifscrub(ifp, ia)
787 	struct ifnet *ifp;
788 	struct in_ifaddr *ia;
789 {
790 
791 	if ((ia->ia_flags & IFA_ROUTE) == 0)
792 		return;
793 	if (ifp->if_flags & (IFF_LOOPBACK|IFF_POINTOPOINT))
794 		rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
795 	else
796 		rtinit(&(ia->ia_ifa), (int)RTM_DELETE, 0);
797 	ia->ia_flags &= ~IFA_ROUTE;
798 }
799 
800 /*
801  * Initialize an interface's internet address
802  * and routing table entry.
803  */
804 int
805 in_ifinit(ifp, ia, sin, scrub)
806 	struct ifnet *ifp;
807 	struct in_ifaddr *ia;
808 	struct sockaddr_in *sin;
809 	int scrub;
810 {
811 	u_int32_t i = sin->sin_addr.s_addr;
812 	struct sockaddr_in oldaddr;
813 	int s = splimp(), flags = RTF_UP, error;
814 
815 	/*
816 	 * Set up new addresses.
817 	 */
818 	oldaddr = ia->ia_addr;
819 	if (ia->ia_addr.sin_family == AF_INET)
820 		LIST_REMOVE(ia, ia_hash);
821 	ia->ia_addr = *sin;
822 	LIST_INSERT_HEAD(&IN_IFADDR_HASH(ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
823 
824 	/*
825 	 * Give the interface a chance to initialize
826 	 * if this is its first address,
827 	 * and to validate the address if necessary.
828 	 */
829 	if (ifp->if_ioctl &&
830 	    (error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia)))
831 		goto bad;
832 	splx(s);
833 	if (scrub) {
834 		ia->ia_ifa.ifa_addr = sintosa(&oldaddr);
835 		in_ifscrub(ifp, ia);
836 		ia->ia_ifa.ifa_addr = sintosa(&ia->ia_addr);
837 	}
838 
839 	if (IN_CLASSA(i))
840 		ia->ia_netmask = IN_CLASSA_NET;
841 	else if (IN_CLASSB(i))
842 		ia->ia_netmask = IN_CLASSB_NET;
843 	else
844 		ia->ia_netmask = IN_CLASSC_NET;
845 	/*
846 	 * The subnet mask usually includes at least the standard network part,
847 	 * but may may be smaller in the case of supernetting.
848 	 * If it is set, we believe it.
849 	 */
850 	if (ia->ia_subnetmask == 0) {
851 		ia->ia_subnetmask = ia->ia_netmask;
852 		ia->ia_sockmask.sin_addr.s_addr = ia->ia_subnetmask;
853 	} else
854 		ia->ia_netmask &= ia->ia_subnetmask;
855 
856 	ia->ia_net = i & ia->ia_netmask;
857 	ia->ia_subnet = i & ia->ia_subnetmask;
858 	in_socktrim(&ia->ia_sockmask);
859 	/* re-calculate the "in_maxmtu" value */
860 	in_setmaxmtu();
861 	/*
862 	 * Add route for the network.
863 	 */
864 	ia->ia_ifa.ifa_metric = ifp->if_metric;
865 	if (ifp->if_flags & IFF_BROADCAST) {
866 		ia->ia_broadaddr.sin_addr.s_addr =
867 			ia->ia_subnet | ~ia->ia_subnetmask;
868 		ia->ia_netbroadcast.s_addr =
869 			ia->ia_net | ~ia->ia_netmask;
870 	} else if (ifp->if_flags & IFF_LOOPBACK) {
871 		ia->ia_ifa.ifa_dstaddr = ia->ia_ifa.ifa_addr;
872 		flags |= RTF_HOST;
873 	} else if (ifp->if_flags & IFF_POINTOPOINT) {
874 		if (ia->ia_dstaddr.sin_family != AF_INET)
875 			return (0);
876 		flags |= RTF_HOST;
877 	}
878 	error = rtinit(&ia->ia_ifa, (int)RTM_ADD, flags);
879 	if (!error)
880 		ia->ia_flags |= IFA_ROUTE;
881 	/*
882 	 * If the interface supports multicast, join the "all hosts"
883 	 * multicast group on that interface.
884 	 */
885 	if (ifp->if_flags & IFF_MULTICAST) {
886 		struct in_addr addr;
887 
888 		addr.s_addr = INADDR_ALLHOSTS_GROUP;
889 		in_addmulti(&addr, ifp);
890 	}
891 	return (error);
892 bad:
893 	splx(s);
894 	LIST_REMOVE(ia, ia_hash);
895 	ia->ia_addr = oldaddr;
896 	if (ia->ia_addr.sin_family == AF_INET)
897 		LIST_INSERT_HEAD(&IN_IFADDR_HASH(ia->ia_addr.sin_addr.s_addr),
898 		    ia, ia_hash);
899 	return (error);
900 }
901 
902 /*
903  * Return 1 if the address might be a local broadcast address.
904  */
905 int
906 in_broadcast(in, ifp)
907 	struct in_addr in;
908 	struct ifnet *ifp;
909 {
910 	struct ifaddr *ifa;
911 
912 	if (in.s_addr == INADDR_BROADCAST ||
913 	    in_nullhost(in))
914 		return 1;
915 	if ((ifp->if_flags & IFF_BROADCAST) == 0)
916 		return 0;
917 	/*
918 	 * Look through the list of addresses for a match
919 	 * with a broadcast address.
920 	 */
921 #define ia (ifatoia(ifa))
922 	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
923 		if (ifa->ifa_addr->sa_family == AF_INET &&
924 		    (in_hosteq(in, ia->ia_broadaddr.sin_addr) ||
925 		     in_hosteq(in, ia->ia_netbroadcast) ||
926 		     (hostzeroisbroadcast &&
927 		      /*
928 		       * Check for old-style (host 0) broadcast.
929 		       */
930 		      (in.s_addr == ia->ia_subnet ||
931 		       in.s_addr == ia->ia_net))))
932 			return 1;
933 	return (0);
934 #undef ia
935 }
936 
937 /*
938  * Add an address to the list of IP multicast addresses for a given interface.
939  */
940 struct in_multi *
941 in_addmulti(ap, ifp)
942 	struct in_addr *ap;
943 	struct ifnet *ifp;
944 {
945 	struct in_multi *inm;
946 	struct ifreq ifr;
947 	struct in_ifaddr *ia;
948 	int s = splsoftnet();
949 
950 	/*
951 	 * See if address already in list.
952 	 */
953 	IN_LOOKUP_MULTI(*ap, ifp, inm);
954 	if (inm != NULL) {
955 		/*
956 		 * Found it; just increment the reference count.
957 		 */
958 		++inm->inm_refcount;
959 	} else {
960 		/*
961 		 * New address; allocate a new multicast record
962 		 * and link it into the interface's multicast list.
963 		 */
964 		inm = (struct in_multi *)malloc(sizeof(*inm),
965 		    M_IPMADDR, M_NOWAIT);
966 		if (inm == NULL) {
967 			splx(s);
968 			return (NULL);
969 		}
970 		inm->inm_addr = *ap;
971 		inm->inm_ifp = ifp;
972 		inm->inm_refcount = 1;
973 		IFP_TO_IA(ifp, ia);
974 		if (ia == NULL) {
975 			free(inm, M_IPMADDR);
976 			splx(s);
977 			return (NULL);
978 		}
979 		inm->inm_ia = ia;
980 		IFAREF(&inm->inm_ia->ia_ifa);
981 		LIST_INSERT_HEAD(&ia->ia_multiaddrs, inm, inm_list);
982 		/*
983 		 * Ask the network driver to update its multicast reception
984 		 * filter appropriately for the new address.
985 		 */
986 		satosin(&ifr.ifr_addr)->sin_len = sizeof(struct sockaddr_in);
987 		satosin(&ifr.ifr_addr)->sin_family = AF_INET;
988 		satosin(&ifr.ifr_addr)->sin_addr = *ap;
989 		if ((ifp->if_ioctl == NULL) ||
990 		    (*ifp->if_ioctl)(ifp, SIOCADDMULTI,(caddr_t)&ifr) != 0) {
991 			LIST_REMOVE(inm, inm_list);
992 			free(inm, M_IPMADDR);
993 			splx(s);
994 			return (NULL);
995 		}
996 		/*
997 		 * Let IGMP know that we have joined a new IP multicast group.
998 		 */
999 		igmp_joingroup(inm);
1000 	}
1001 	splx(s);
1002 	return (inm);
1003 }
1004 
1005 /*
1006  * Delete a multicast address record.
1007  */
1008 void
1009 in_delmulti(inm)
1010 	struct in_multi *inm;
1011 {
1012 	struct ifreq ifr;
1013 	int s = splsoftnet();
1014 
1015 	if (--inm->inm_refcount == 0) {
1016 		/*
1017 		 * No remaining claims to this record; let IGMP know that
1018 		 * we are leaving the multicast group.
1019 		 */
1020 		igmp_leavegroup(inm);
1021 		/*
1022 		 * Unlink from list.
1023 		 */
1024 		LIST_REMOVE(inm, inm_list);
1025 		IFAFREE(&inm->inm_ia->ia_ifa);
1026 		/*
1027 		 * Notify the network driver to update its multicast reception
1028 		 * filter.
1029 		 */
1030 		satosin(&ifr.ifr_addr)->sin_family = AF_INET;
1031 		satosin(&ifr.ifr_addr)->sin_addr = inm->inm_addr;
1032 		(*inm->inm_ifp->if_ioctl)(inm->inm_ifp, SIOCDELMULTI,
1033 							     (caddr_t)&ifr);
1034 		free(inm, M_IPMADDR);
1035 	}
1036 	splx(s);
1037 }
1038 #endif
1039