xref: /freebsd/sys/net/if_gif.c (revision 729362425c09cf6b362366aabc6fb547eee8035a) 
1 /*	$FreeBSD$	*/
2 /*	$KAME: if_gif.c,v 1.87 2001/10/19 08:50:27 itojun Exp $	*/
3 
4 /*
5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the project nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include "opt_inet.h"
34 #include "opt_inet6.h"
35 #include "opt_mac.h"
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/kernel.h>
40 #include <sys/mac.h>
41 #include <sys/malloc.h>
42 #include <sys/mbuf.h>
43 #include <sys/socket.h>
44 #include <sys/sockio.h>
45 #include <sys/errno.h>
46 #include <sys/time.h>
47 #include <sys/sysctl.h>
48 #include <sys/syslog.h>
49 #include <sys/protosw.h>
50 #include <sys/conf.h>
51 #include <machine/cpu.h>
52 
53 #include <net/if.h>
54 #include <net/if_types.h>
55 #include <net/netisr.h>
56 #include <net/route.h>
57 #include <net/bpf.h>
58 
59 #include <netinet/in.h>
60 #include <netinet/in_systm.h>
61 #include <netinet/ip.h>
62 #ifdef	INET
63 #include <netinet/in_var.h>
64 #include <netinet/in_gif.h>
65 #include <netinet/ip_var.h>
66 #endif	/* INET */
67 
68 #ifdef INET6
69 #ifndef INET
70 #include <netinet/in.h>
71 #endif
72 #include <netinet6/in6_var.h>
73 #include <netinet/ip6.h>
74 #include <netinet6/ip6_var.h>
75 #include <netinet6/in6_gif.h>
76 #include <netinet6/ip6protosw.h>
77 #endif /* INET6 */
78 
79 #include <netinet/ip_encap.h>
80 #include <net/if_gif.h>
81 
82 #include <net/net_osdep.h>
83 
84 #define GIFNAME		"gif"
85 
86 static MALLOC_DEFINE(M_GIF, "gif", "Generic Tunnel Interface");
87 static LIST_HEAD(, gif_softc) gif_softc_list;
88 
89 void	(*ng_gif_input_p)(struct ifnet *ifp, struct mbuf **mp, int af);
90 void	(*ng_gif_input_orphan_p)(struct ifnet *ifp, struct mbuf *m, int af);
91 void	(*ng_gif_attach_p)(struct ifnet *ifp);
92 void	(*ng_gif_detach_p)(struct ifnet *ifp);
93 
94 int	gif_clone_create(struct if_clone *, int);
95 void	gif_clone_destroy(struct ifnet *);
96 
97 struct if_clone gif_cloner = IF_CLONE_INITIALIZER("gif",
98     gif_clone_create, gif_clone_destroy, 0, IF_MAXUNIT);
99 
100 static int gifmodevent(module_t, int, void *);
101 
102 SYSCTL_DECL(_net_link);
103 SYSCTL_NODE(_net_link, IFT_GIF, gif, CTLFLAG_RW, 0,
104     "Generic Tunnel Interface");
105 #ifndef MAX_GIF_NEST
106 /*
107  * This macro controls the default upper limitation on nesting of gif tunnels.
108  * Since, setting a large value to this macro with a careless configuration
109  * may introduce system crash, we don't allow any nestings by default.
110  * If you need to configure nested gif tunnels, you can define this macro
111  * in your kernel configuration file.  However, if you do so, please be
112  * careful to configure the tunnels so that it won't make a loop.
113  */
114 #define MAX_GIF_NEST 1
115 #endif
116 static int max_gif_nesting = MAX_GIF_NEST;
117 SYSCTL_INT(_net_link_gif, OID_AUTO, max_nesting, CTLFLAG_RW,
118     &max_gif_nesting, 0, "Max nested tunnels");
119 
120 /*
121  * By default, we disallow creation of multiple tunnels between the same
122  * pair of addresses.  Some applications require this functionality so
123  * we allow control over this check here.
124  */
125 #ifdef XBONEHACK
126 static int parallel_tunnels = 1;
127 #else
128 static int parallel_tunnels = 0;
129 #endif
130 SYSCTL_INT(_net_link_gif, OID_AUTO, parallel_tunnels, CTLFLAG_RW,
131     &parallel_tunnels, 0, "Allow parallel tunnels?");
132 
133 int
134 gif_clone_create(ifc, unit)
135 	struct if_clone *ifc;
136 	int unit;
137 {
138 	struct gif_softc *sc;
139 
140 	sc = malloc (sizeof(struct gif_softc), M_GIF, M_WAITOK);
141 	bzero(sc, sizeof(struct gif_softc));
142 
143 	sc->gif_if.if_softc = sc;
144 	sc->gif_if.if_name = GIFNAME;
145 	sc->gif_if.if_unit = unit;
146 
147 	gifattach0(sc);
148 
149 	LIST_INSERT_HEAD(&gif_softc_list, sc, gif_list);
150 	return (0);
151 }
152 
153 void
154 gifattach0(sc)
155 	struct gif_softc *sc;
156 {
157 
158 	sc->encap_cookie4 = sc->encap_cookie6 = NULL;
159 
160 	sc->gif_if.if_addrlen = 0;
161 	sc->gif_if.if_mtu    = GIF_MTU;
162 	sc->gif_if.if_flags  = IFF_POINTOPOINT | IFF_MULTICAST;
163 #if 0
164 	/* turn off ingress filter */
165 	sc->gif_if.if_flags  |= IFF_LINK2;
166 #endif
167 	sc->gif_if.if_ioctl  = gif_ioctl;
168 	sc->gif_if.if_output = gif_output;
169 	sc->gif_if.if_type   = IFT_GIF;
170 	sc->gif_if.if_snd.ifq_maxlen = IFQ_MAXLEN;
171 	if_attach(&sc->gif_if);
172 	bpfattach(&sc->gif_if, DLT_NULL, sizeof(u_int));
173 	if (ng_gif_attach_p != NULL)
174 		(*ng_gif_attach_p)(&sc->gif_if);
175 }
176 
177 void
178 gif_clone_destroy(ifp)
179 	struct ifnet *ifp;
180 {
181 	int err;
182 	struct gif_softc *sc = ifp->if_softc;
183 
184 	gif_delete_tunnel(&sc->gif_if);
185 	LIST_REMOVE(sc, gif_list);
186 #ifdef INET6
187 	if (sc->encap_cookie6 != NULL) {
188 		err = encap_detach(sc->encap_cookie6);
189 		KASSERT(err == 0, ("Unexpected error detaching encap_cookie6"));
190 	}
191 #endif
192 #ifdef INET
193 	if (sc->encap_cookie4 != NULL) {
194 		err = encap_detach(sc->encap_cookie4);
195 		KASSERT(err == 0, ("Unexpected error detaching encap_cookie4"));
196 	}
197 #endif
198 
199 	if (ng_gif_detach_p != NULL)
200 		(*ng_gif_detach_p)(ifp);
201 	bpfdetach(ifp);
202 	if_detach(ifp);
203 
204 	free(sc, M_GIF);
205 }
206 
207 static int
208 gifmodevent(mod, type, data)
209 	module_t mod;
210 	int type;
211 	void *data;
212 {
213 
214 	switch (type) {
215 	case MOD_LOAD:
216 		LIST_INIT(&gif_softc_list);
217 		if_clone_attach(&gif_cloner);
218 
219 #ifdef INET6
220 		ip6_gif_hlim = GIF_HLIM;
221 #endif
222 
223 		break;
224 	case MOD_UNLOAD:
225 		if_clone_detach(&gif_cloner);
226 
227 		while (!LIST_EMPTY(&gif_softc_list))
228 			gif_clone_destroy(&LIST_FIRST(&gif_softc_list)->gif_if);
229 
230 #ifdef INET6
231 		ip6_gif_hlim = 0;
232 #endif
233 		break;
234 	}
235 	return 0;
236 }
237 
238 static moduledata_t gif_mod = {
239 	"if_gif",
240 	gifmodevent,
241 	0
242 };
243 
244 DECLARE_MODULE(if_gif, gif_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
245 MODULE_VERSION(if_gif, 1);
246 
247 int
248 gif_encapcheck(m, off, proto, arg)
249 	const struct mbuf *m;
250 	int off;
251 	int proto;
252 	void *arg;
253 {
254 	struct ip ip;
255 	struct gif_softc *sc;
256 
257 	sc = (struct gif_softc *)arg;
258 	if (sc == NULL)
259 		return 0;
260 
261 	if ((sc->gif_if.if_flags & IFF_UP) == 0)
262 		return 0;
263 
264 	/* no physical address */
265 	if (!sc->gif_psrc || !sc->gif_pdst)
266 		return 0;
267 
268 	switch (proto) {
269 #ifdef INET
270 	case IPPROTO_IPV4:
271 		break;
272 #endif
273 #ifdef INET6
274 	case IPPROTO_IPV6:
275 		break;
276 #endif
277 	default:
278 		return 0;
279 	}
280 
281 	/* Bail on short packets */
282 	if (m->m_pkthdr.len < sizeof(ip))
283 		return 0;
284 
285 	m_copydata(m, 0, sizeof(ip), (caddr_t)&ip);
286 
287 	switch (ip.ip_v) {
288 #ifdef INET
289 	case 4:
290 		if (sc->gif_psrc->sa_family != AF_INET ||
291 		    sc->gif_pdst->sa_family != AF_INET)
292 			return 0;
293 		return gif_encapcheck4(m, off, proto, arg);
294 #endif
295 #ifdef INET6
296 	case 6:
297 		if (m->m_pkthdr.len < sizeof(struct ip6_hdr))
298 			return 0;
299 		if (sc->gif_psrc->sa_family != AF_INET6 ||
300 		    sc->gif_pdst->sa_family != AF_INET6)
301 			return 0;
302 		return gif_encapcheck6(m, off, proto, arg);
303 #endif
304 	default:
305 		return 0;
306 	}
307 }
308 
309 int
310 gif_output(ifp, m, dst, rt)
311 	struct ifnet *ifp;
312 	struct mbuf *m;
313 	struct sockaddr *dst;
314 	struct rtentry *rt;	/* added in net2 */
315 {
316 	struct gif_softc *sc = (struct gif_softc*)ifp;
317 	int error = 0;
318 	static int called = 0;	/* XXX: MUTEX */
319 
320 #ifdef MAC
321 	error = mac_check_ifnet_transmit(ifp, m);
322 	if (error) {
323 		m_freem(m);
324 		goto end;
325 	}
326 #endif
327 
328 	/*
329 	 * gif may cause infinite recursion calls when misconfigured.
330 	 * We'll prevent this by introducing upper limit.
331 	 * XXX: this mechanism may introduce another problem about
332 	 *      mutual exclusion of the variable CALLED, especially if we
333 	 *      use kernel thread.
334 	 */
335 	if (++called > max_gif_nesting) {
336 		log(LOG_NOTICE,
337 		    "gif_output: recursively called too many times(%d)\n",
338 		    called);
339 		m_freem(m);
340 		error = EIO;	/* is there better errno? */
341 		goto end;
342 	}
343 
344 	m->m_flags &= ~(M_BCAST|M_MCAST);
345 	if (!(ifp->if_flags & IFF_UP) ||
346 	    sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
347 		m_freem(m);
348 		error = ENETDOWN;
349 		goto end;
350 	}
351 
352 	if (ifp->if_bpf) {
353 		/*
354 		 * We need to prepend the address family as
355 		 * a four byte field.  Cons up a dummy header
356 		 * to pacify bpf.  This is safe because bpf
357 		 * will only read from the mbuf (i.e., it won't
358 		 * try to free it or keep a pointer a to it).
359 		 */
360 		struct mbuf m0;
361 		u_int32_t af = dst->sa_family;
362 
363 		m0.m_next = m;
364 		m0.m_len = 4;
365 		m0.m_data = (char *)&af;
366 
367 		BPF_MTAP(ifp, &m0);
368 	}
369 	ifp->if_opackets++;
370 	ifp->if_obytes += m->m_pkthdr.len;
371 
372 	/* inner AF-specific encapsulation */
373 
374 	/* XXX should we check if our outer source is legal? */
375 
376 	/* dispatch to output logic based on outer AF */
377 	switch (sc->gif_psrc->sa_family) {
378 #ifdef INET
379 	case AF_INET:
380 		error = in_gif_output(ifp, dst->sa_family, m);
381 		break;
382 #endif
383 #ifdef INET6
384 	case AF_INET6:
385 		error = in6_gif_output(ifp, dst->sa_family, m);
386 		break;
387 #endif
388 	default:
389 		m_freem(m);
390 		error = ENETDOWN;
391 		goto end;
392 	}
393 
394   end:
395 	called = 0;		/* reset recursion counter */
396 	if (error)
397 		ifp->if_oerrors++;
398 	return error;
399 }
400 
401 void
402 gif_input(m, af, ifp)
403 	struct mbuf *m;
404 	int af;
405 	struct ifnet *ifp;
406 {
407 	int isr;
408 
409 	if (ifp == NULL) {
410 		/* just in case */
411 		m_freem(m);
412 		return;
413 	}
414 
415 	m->m_pkthdr.rcvif = ifp;
416 
417 #ifdef MAC
418 	mac_create_mbuf_from_ifnet(ifp, m);
419 #endif
420 
421 	if (ifp->if_bpf) {
422 		/*
423 		 * We need to prepend the address family as
424 		 * a four byte field.  Cons up a dummy header
425 		 * to pacify bpf.  This is safe because bpf
426 		 * will only read from the mbuf (i.e., it won't
427 		 * try to free it or keep a pointer a to it).
428 		 */
429 		struct mbuf m0;
430 		u_int32_t af1 = af;
431 
432 		m0.m_next = m;
433 		m0.m_len = 4;
434 		m0.m_data = (char *)&af1;
435 
436 		BPF_MTAP(ifp, &m0);
437 	}
438 
439 	if (ng_gif_input_p != NULL) {
440 		(*ng_gif_input_p)(ifp, &m, af);
441 		if (m == NULL)
442 			return;
443 	}
444 
445 	/*
446 	 * Put the packet to the network layer input queue according to the
447 	 * specified address family.
448 	 * Note: older versions of gif_input directly called network layer
449 	 * input functions, e.g. ip6_input, here.  We changed the policy to
450 	 * prevent too many recursive calls of such input functions, which
451 	 * might cause kernel panic.  But the change may introduce another
452 	 * problem; if the input queue is full, packets are discarded.
453 	 * The kernel stack overflow really happened, and we believed
454 	 * queue-full rarely occurs, so we changed the policy.
455 	 */
456 	switch (af) {
457 #ifdef INET
458 	case AF_INET:
459 		isr = NETISR_IP;
460 		break;
461 #endif
462 #ifdef INET6
463 	case AF_INET6:
464 		isr = NETISR_IPV6;
465 		break;
466 #endif
467 	default:
468 		if (ng_gif_input_orphan_p != NULL)
469 			(*ng_gif_input_orphan_p)(ifp, m, af);
470 		else
471 			m_freem(m);
472 		return;
473 	}
474 
475 	ifp->if_ipackets++;
476 	ifp->if_ibytes += m->m_pkthdr.len;
477 	netisr_dispatch(isr, m);
478 }
479 
480 /* XXX how should we handle IPv6 scope on SIOC[GS]IFPHYADDR? */
481 int
482 gif_ioctl(ifp, cmd, data)
483 	struct ifnet *ifp;
484 	u_long cmd;
485 	caddr_t data;
486 {
487 	struct gif_softc *sc  = (struct gif_softc*)ifp;
488 	struct ifreq     *ifr = (struct ifreq*)data;
489 	int error = 0, size;
490 	struct sockaddr *dst, *src;
491 #ifdef	SIOCSIFMTU /* xxx */
492 	u_long mtu;
493 #endif
494 
495 	switch (cmd) {
496 	case SIOCSIFADDR:
497 		ifp->if_flags |= IFF_UP;
498 		break;
499 
500 	case SIOCSIFDSTADDR:
501 		break;
502 
503 	case SIOCADDMULTI:
504 	case SIOCDELMULTI:
505 		break;
506 
507 #ifdef	SIOCSIFMTU /* xxx */
508 	case SIOCGIFMTU:
509 		break;
510 
511 	case SIOCSIFMTU:
512 		mtu = ifr->ifr_mtu;
513 		if (mtu < GIF_MTU_MIN || mtu > GIF_MTU_MAX)
514 			return (EINVAL);
515 		ifp->if_mtu = mtu;
516 		break;
517 #endif /* SIOCSIFMTU */
518 
519 #ifdef INET
520 	case SIOCSIFPHYADDR:
521 #endif
522 #ifdef INET6
523 	case SIOCSIFPHYADDR_IN6:
524 #endif /* INET6 */
525 	case SIOCSLIFPHYADDR:
526 		switch (cmd) {
527 #ifdef INET
528 		case SIOCSIFPHYADDR:
529 			src = (struct sockaddr *)
530 				&(((struct in_aliasreq *)data)->ifra_addr);
531 			dst = (struct sockaddr *)
532 				&(((struct in_aliasreq *)data)->ifra_dstaddr);
533 			break;
534 #endif
535 #ifdef INET6
536 		case SIOCSIFPHYADDR_IN6:
537 			src = (struct sockaddr *)
538 				&(((struct in6_aliasreq *)data)->ifra_addr);
539 			dst = (struct sockaddr *)
540 				&(((struct in6_aliasreq *)data)->ifra_dstaddr);
541 			break;
542 #endif
543 		case SIOCSLIFPHYADDR:
544 			src = (struct sockaddr *)
545 				&(((struct if_laddrreq *)data)->addr);
546 			dst = (struct sockaddr *)
547 				&(((struct if_laddrreq *)data)->dstaddr);
548 			break;
549 		default:
550 			return EINVAL;
551 		}
552 
553 		/* sa_family must be equal */
554 		if (src->sa_family != dst->sa_family)
555 			return EINVAL;
556 
557 		/* validate sa_len */
558 		switch (src->sa_family) {
559 #ifdef INET
560 		case AF_INET:
561 			if (src->sa_len != sizeof(struct sockaddr_in))
562 				return EINVAL;
563 			break;
564 #endif
565 #ifdef INET6
566 		case AF_INET6:
567 			if (src->sa_len != sizeof(struct sockaddr_in6))
568 				return EINVAL;
569 			break;
570 #endif
571 		default:
572 			return EAFNOSUPPORT;
573 		}
574 		switch (dst->sa_family) {
575 #ifdef INET
576 		case AF_INET:
577 			if (dst->sa_len != sizeof(struct sockaddr_in))
578 				return EINVAL;
579 			break;
580 #endif
581 #ifdef INET6
582 		case AF_INET6:
583 			if (dst->sa_len != sizeof(struct sockaddr_in6))
584 				return EINVAL;
585 			break;
586 #endif
587 		default:
588 			return EAFNOSUPPORT;
589 		}
590 
591 		/* check sa_family looks sane for the cmd */
592 		switch (cmd) {
593 		case SIOCSIFPHYADDR:
594 			if (src->sa_family == AF_INET)
595 				break;
596 			return EAFNOSUPPORT;
597 #ifdef INET6
598 		case SIOCSIFPHYADDR_IN6:
599 			if (src->sa_family == AF_INET6)
600 				break;
601 			return EAFNOSUPPORT;
602 #endif /* INET6 */
603 		case SIOCSLIFPHYADDR:
604 			/* checks done in the above */
605 			break;
606 		}
607 
608 		error = gif_set_tunnel(&sc->gif_if, src, dst);
609 		break;
610 
611 #ifdef SIOCDIFPHYADDR
612 	case SIOCDIFPHYADDR:
613 		gif_delete_tunnel(&sc->gif_if);
614 		break;
615 #endif
616 
617 	case SIOCGIFPSRCADDR:
618 #ifdef INET6
619 	case SIOCGIFPSRCADDR_IN6:
620 #endif /* INET6 */
621 		if (sc->gif_psrc == NULL) {
622 			error = EADDRNOTAVAIL;
623 			goto bad;
624 		}
625 		src = sc->gif_psrc;
626 		switch (cmd) {
627 #ifdef INET
628 		case SIOCGIFPSRCADDR:
629 			dst = &ifr->ifr_addr;
630 			size = sizeof(ifr->ifr_addr);
631 			break;
632 #endif /* INET */
633 #ifdef INET6
634 		case SIOCGIFPSRCADDR_IN6:
635 			dst = (struct sockaddr *)
636 				&(((struct in6_ifreq *)data)->ifr_addr);
637 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
638 			break;
639 #endif /* INET6 */
640 		default:
641 			error = EADDRNOTAVAIL;
642 			goto bad;
643 		}
644 		if (src->sa_len > size)
645 			return EINVAL;
646 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
647 		break;
648 
649 	case SIOCGIFPDSTADDR:
650 #ifdef INET6
651 	case SIOCGIFPDSTADDR_IN6:
652 #endif /* INET6 */
653 		if (sc->gif_pdst == NULL) {
654 			error = EADDRNOTAVAIL;
655 			goto bad;
656 		}
657 		src = sc->gif_pdst;
658 		switch (cmd) {
659 #ifdef INET
660 		case SIOCGIFPDSTADDR:
661 			dst = &ifr->ifr_addr;
662 			size = sizeof(ifr->ifr_addr);
663 			break;
664 #endif /* INET */
665 #ifdef INET6
666 		case SIOCGIFPDSTADDR_IN6:
667 			dst = (struct sockaddr *)
668 				&(((struct in6_ifreq *)data)->ifr_addr);
669 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
670 			break;
671 #endif /* INET6 */
672 		default:
673 			error = EADDRNOTAVAIL;
674 			goto bad;
675 		}
676 		if (src->sa_len > size)
677 			return EINVAL;
678 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
679 		break;
680 
681 	case SIOCGLIFPHYADDR:
682 		if (sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
683 			error = EADDRNOTAVAIL;
684 			goto bad;
685 		}
686 
687 		/* copy src */
688 		src = sc->gif_psrc;
689 		dst = (struct sockaddr *)
690 			&(((struct if_laddrreq *)data)->addr);
691 		size = sizeof(((struct if_laddrreq *)data)->addr);
692 		if (src->sa_len > size)
693 			return EINVAL;
694 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
695 
696 		/* copy dst */
697 		src = sc->gif_pdst;
698 		dst = (struct sockaddr *)
699 			&(((struct if_laddrreq *)data)->dstaddr);
700 		size = sizeof(((struct if_laddrreq *)data)->dstaddr);
701 		if (src->sa_len > size)
702 			return EINVAL;
703 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
704 		break;
705 
706 	case SIOCSIFFLAGS:
707 		/* if_ioctl() takes care of it */
708 		break;
709 
710 	default:
711 		error = EINVAL;
712 		break;
713 	}
714  bad:
715 	return error;
716 }
717 
718 int
719 gif_set_tunnel(ifp, src, dst)
720 	struct ifnet *ifp;
721 	struct sockaddr *src;
722 	struct sockaddr *dst;
723 {
724 	struct gif_softc *sc = (struct gif_softc *)ifp;
725 	struct gif_softc *sc2;
726 	struct sockaddr *osrc, *odst, *sa;
727 	int s;
728 	int error = 0;
729 
730 	s = splnet();
731 
732 	LIST_FOREACH(sc2, &gif_softc_list, gif_list) {
733 		if (sc2 == sc)
734 			continue;
735 		if (!sc2->gif_pdst || !sc2->gif_psrc)
736 			continue;
737 		if (sc2->gif_pdst->sa_family != dst->sa_family ||
738 		    sc2->gif_pdst->sa_len != dst->sa_len ||
739 		    sc2->gif_psrc->sa_family != src->sa_family ||
740 		    sc2->gif_psrc->sa_len != src->sa_len)
741 			continue;
742 
743 		/*
744 		 * Disallow parallel tunnels unless instructed
745 		 * otherwise.
746 		 */
747 		if (!parallel_tunnels &&
748 		    bcmp(sc2->gif_pdst, dst, dst->sa_len) == 0 &&
749 		    bcmp(sc2->gif_psrc, src, src->sa_len) == 0) {
750 			error = EADDRNOTAVAIL;
751 			goto bad;
752 		}
753 
754 		/* XXX both end must be valid? (I mean, not 0.0.0.0) */
755 	}
756 
757 	/* XXX we can detach from both, but be polite just in case */
758 	if (sc->gif_psrc)
759 		switch (sc->gif_psrc->sa_family) {
760 #ifdef INET
761 		case AF_INET:
762 			(void)in_gif_detach(sc);
763 			break;
764 #endif
765 #ifdef INET6
766 		case AF_INET6:
767 			(void)in6_gif_detach(sc);
768 			break;
769 #endif
770 		}
771 
772 	osrc = sc->gif_psrc;
773 	sa = (struct sockaddr *)malloc(src->sa_len, M_IFADDR, M_WAITOK);
774 	bcopy((caddr_t)src, (caddr_t)sa, src->sa_len);
775 	sc->gif_psrc = sa;
776 
777 	odst = sc->gif_pdst;
778 	sa = (struct sockaddr *)malloc(dst->sa_len, M_IFADDR, M_WAITOK);
779 	bcopy((caddr_t)dst, (caddr_t)sa, dst->sa_len);
780 	sc->gif_pdst = sa;
781 
782 	switch (sc->gif_psrc->sa_family) {
783 #ifdef INET
784 	case AF_INET:
785 		error = in_gif_attach(sc);
786 		break;
787 #endif
788 #ifdef INET6
789 	case AF_INET6:
790 		error = in6_gif_attach(sc);
791 		break;
792 #endif
793 	}
794 	if (error) {
795 		/* rollback */
796 		free((caddr_t)sc->gif_psrc, M_IFADDR);
797 		free((caddr_t)sc->gif_pdst, M_IFADDR);
798 		sc->gif_psrc = osrc;
799 		sc->gif_pdst = odst;
800 		goto bad;
801 	}
802 
803 	if (osrc)
804 		free((caddr_t)osrc, M_IFADDR);
805 	if (odst)
806 		free((caddr_t)odst, M_IFADDR);
807 
808 	if (sc->gif_psrc && sc->gif_pdst)
809 		ifp->if_flags |= IFF_RUNNING;
810 	else
811 		ifp->if_flags &= ~IFF_RUNNING;
812 	splx(s);
813 
814 	return 0;
815 
816  bad:
817 	if (sc->gif_psrc && sc->gif_pdst)
818 		ifp->if_flags |= IFF_RUNNING;
819 	else
820 		ifp->if_flags &= ~IFF_RUNNING;
821 	splx(s);
822 
823 	return error;
824 }
825 
826 void
827 gif_delete_tunnel(ifp)
828 	struct ifnet *ifp;
829 {
830 	struct gif_softc *sc = (struct gif_softc *)ifp;
831 	int s;
832 
833 	s = splnet();
834 
835 	if (sc->gif_psrc) {
836 		free((caddr_t)sc->gif_psrc, M_IFADDR);
837 		sc->gif_psrc = NULL;
838 	}
839 	if (sc->gif_pdst) {
840 		free((caddr_t)sc->gif_pdst, M_IFADDR);
841 		sc->gif_pdst = NULL;
842 	}
843 	/* it is safe to detach from both */
844 #ifdef INET
845 	(void)in_gif_detach(sc);
846 #endif
847 #ifdef INET6
848 	(void)in6_gif_detach(sc);
849 #endif
850 
851 	if (sc->gif_psrc && sc->gif_pdst)
852 		ifp->if_flags |= IFF_RUNNING;
853 	else
854 		ifp->if_flags &= ~IFF_RUNNING;
855 	splx(s);
856 }
857