xref: /dragonfly/sys/net/gif/if_gif.c (revision 6fb88001) 
1 /*
2  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
3  * 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. Neither the name of the project nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD: src/sys/net/if_gif.c,v 1.4.2.15 2002/11/08 16:57:13 ume Exp $
30  * $DragonFly: src/sys/net/gif/if_gif.c,v 1.15 2005/12/11 13:00:16 swildner Exp $
31  * $KAME: if_gif.c,v 1.87 2001/10/19 08:50:27 itojun Exp $
32  */
33 
34 #include "opt_inet.h"
35 #include "opt_inet6.h"
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/kernel.h>
40 #include <sys/malloc.h>
41 #include <sys/mbuf.h>
42 #include <sys/socket.h>
43 #include <sys/sockio.h>
44 #include <sys/errno.h>
45 #include <sys/time.h>
46 #include <sys/sysctl.h>
47 #include <sys/syslog.h>
48 #include <sys/protosw.h>
49 #include <sys/conf.h>
50 #include <sys/thread2.h>
51 #include <machine/bus.h>	/* XXX: Shouldn't really be required! */
52 #include <machine/cpu.h>
53 
54 #include <net/if.h>
55 #include <net/if_types.h>
56 #include <net/netisr.h>
57 #include <net/route.h>
58 #include <net/bpf.h>
59 
60 #include <netinet/in.h>
61 #include <netinet/in_systm.h>
62 #include <netinet/ip.h>
63 #ifdef	INET
64 #include <netinet/in_var.h>
65 #include <netinet/in_gif.h>
66 #include <netinet/ip_var.h>
67 #endif	/* INET */
68 
69 #ifdef INET6
70 #ifndef INET
71 #include <netinet/in.h>
72 #endif
73 #include <netinet6/in6_var.h>
74 #include <netinet/ip6.h>
75 #include <netinet6/ip6_var.h>
76 #include <netinet6/in6_gif.h>
77 #include <netinet6/ip6protosw.h>
78 #endif /* INET6 */
79 
80 #include <netinet/ip_encap.h>
81 #include "if_gif.h"
82 
83 #include <net/net_osdep.h>
84 
85 #define GIFNAME		"gif"
86 
87 static MALLOC_DEFINE(M_GIF, "gif", "Generic Tunnel Interface");
88 LIST_HEAD(, gif_softc) gif_softc_list;
89 
90 int	gif_clone_create (struct if_clone *, int);
91 void	gif_clone_destroy (struct ifnet *);
92 
93 struct if_clone gif_cloner = IF_CLONE_INITIALIZER("gif", gif_clone_create,
94     gif_clone_destroy, 0, IF_MAXUNIT);
95 
96 static int gifmodevent (module_t, int, void *);
97 
98 SYSCTL_DECL(_net_link);
99 SYSCTL_NODE(_net_link, IFT_GIF, gif, CTLFLAG_RW, 0,
100     "Generic Tunnel Interface");
101 #ifndef MAX_GIF_NEST
102 /*
103  * This macro controls the default upper limitation on nesting of gif tunnels.
104  * Since, setting a large value to this macro with a careless configuration
105  * may introduce system crash, we don't allow any nestings by default.
106  * If you need to configure nested gif tunnels, you can define this macro
107  * in your kernel configuration file.  However, if you do so, please be
108  * careful to configure the tunnels so that it won't make a loop.
109  */
110 #define MAX_GIF_NEST 1
111 #endif
112 static int max_gif_nesting = MAX_GIF_NEST;
113 SYSCTL_INT(_net_link_gif, OID_AUTO, max_nesting, CTLFLAG_RW,
114     &max_gif_nesting, 0, "Max nested tunnels");
115 
116 /*
117  * By default, we disallow creation of multiple tunnels between the same
118  * pair of addresses.  Some applications require this functionality so
119  * we allow control over this check here.
120  */
121 #ifdef XBONEHACK
122 static int parallel_tunnels = 1;
123 #else
124 static int parallel_tunnels = 0;
125 #endif
126 SYSCTL_INT(_net_link_gif, OID_AUTO, parallel_tunnels, CTLFLAG_RW,
127     &parallel_tunnels, 0, "Allow parallel tunnels?");
128 
129 int
130 gif_clone_create(struct if_clone *ifc, int unit)
131 {
132 	struct gif_softc *sc;
133 
134 	sc = malloc (sizeof(struct gif_softc), M_GIF, M_WAITOK);
135 	bzero(sc, sizeof(struct gif_softc));
136 
137 	sc->gif_if.if_softc = sc;
138 	if_initname(&(sc->gif_if), GIFNAME, unit);
139 
140 	gifattach0(sc);
141 
142 	LIST_INSERT_HEAD(&gif_softc_list, sc, gif_list);
143 	return (0);
144 }
145 
146 void
147 gifattach0(struct gif_softc *sc)
148 {
149 
150 	sc->encap_cookie4 = sc->encap_cookie6 = NULL;
151 
152 	sc->gif_if.if_addrlen = 0;
153 	sc->gif_if.if_mtu    = GIF_MTU;
154 	sc->gif_if.if_flags  = IFF_POINTOPOINT | IFF_MULTICAST;
155 #if 0
156 	/* turn off ingress filter */
157 	sc->gif_if.if_flags  |= IFF_LINK2;
158 #endif
159 	sc->gif_if.if_ioctl  = gif_ioctl;
160 	sc->gif_if.if_output = gif_output;
161 	sc->gif_if.if_type   = IFT_GIF;
162 	sc->gif_if.if_snd.ifq_maxlen = IFQ_MAXLEN;
163 	if_attach(&sc->gif_if, NULL);
164 	bpfattach(&sc->gif_if, DLT_NULL, sizeof(u_int));
165 }
166 
167 void
168 gif_clone_destroy(struct ifnet *ifp)
169 {
170 	int err;
171 	struct gif_softc *sc = ifp->if_softc;
172 
173 	gif_delete_tunnel(&sc->gif_if);
174 	LIST_REMOVE(sc, gif_list);
175 #ifdef INET6
176 	if (sc->encap_cookie6 != NULL) {
177 		err = encap_detach(sc->encap_cookie6);
178 		KASSERT(err == 0, ("Unexpected error detaching encap_cookie6"));
179 	}
180 #endif
181 #ifdef INET
182 	if (sc->encap_cookie4 != NULL) {
183 		err = encap_detach(sc->encap_cookie4);
184 		KASSERT(err == 0, ("Unexpected error detaching encap_cookie4"));
185 	}
186 #endif
187 
188 	bpfdetach(ifp);
189 	if_detach(ifp);
190 
191 	free(sc, M_GIF);
192 }
193 
194 static int
195 gifmodevent(module_t mod, int type, void *data)
196 {
197 
198 	switch (type) {
199 	case MOD_LOAD:
200 		LIST_INIT(&gif_softc_list);
201 		if_clone_attach(&gif_cloner);
202 
203 #ifdef INET6
204 		ip6_gif_hlim = GIF_HLIM;
205 #endif
206 
207 		break;
208 	case MOD_UNLOAD:
209 		if_clone_detach(&gif_cloner);
210 
211 		while (!LIST_EMPTY(&gif_softc_list))
212 			gif_clone_destroy(&LIST_FIRST(&gif_softc_list)->gif_if);
213 
214 #ifdef INET6
215 		ip6_gif_hlim = 0;
216 #endif
217 		break;
218 	}
219 	return 0;
220 }
221 
222 static moduledata_t gif_mod = {
223 	"if_gif",
224 	gifmodevent,
225 	0
226 };
227 
228 DECLARE_MODULE(if_gif, gif_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
229 
230 int
231 gif_encapcheck(const struct mbuf *m, int off, int proto, void *arg)
232 {
233 	struct ip ip;
234 	struct gif_softc *sc;
235 
236 	sc = (struct gif_softc *)arg;
237 	if (sc == NULL)
238 		return 0;
239 
240 	if ((sc->gif_if.if_flags & IFF_UP) == 0)
241 		return 0;
242 
243 	/* no physical address */
244 	if (!sc->gif_psrc || !sc->gif_pdst)
245 		return 0;
246 
247 	switch (proto) {
248 #ifdef INET
249 	case IPPROTO_IPV4:
250 		break;
251 #endif
252 #ifdef INET6
253 	case IPPROTO_IPV6:
254 		break;
255 #endif
256 	default:
257 		return 0;
258 	}
259 
260 	/* Bail on short packets */
261 	if (m->m_pkthdr.len < sizeof(ip))
262 		return 0;
263 
264 	m_copydata(m, 0, sizeof(ip), (caddr_t)&ip);
265 
266 	switch (ip.ip_v) {
267 #ifdef INET
268 	case 4:
269 		if (sc->gif_psrc->sa_family != AF_INET ||
270 		    sc->gif_pdst->sa_family != AF_INET)
271 			return 0;
272 		return gif_encapcheck4(m, off, proto, arg);
273 #endif
274 #ifdef INET6
275 	case 6:
276 		if (m->m_pkthdr.len < sizeof(struct ip6_hdr))
277 			return 0;
278 		if (sc->gif_psrc->sa_family != AF_INET6 ||
279 		    sc->gif_pdst->sa_family != AF_INET6)
280 			return 0;
281 		return gif_encapcheck6(m, off, proto, arg);
282 #endif
283 	default:
284 		return 0;
285 	}
286 }
287 
288 /*
289  * Parameters:
290  *	rt:	added in net2
291  */
292 int
293 gif_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
294 	   struct rtentry *rt)
295 {
296 	struct gif_softc *sc = (struct gif_softc*)ifp;
297 	int error = 0;
298 	static int called = 0;	/* XXX: MUTEX */
299 
300 	/*
301 	 * gif may cause infinite recursion calls when misconfigured.
302 	 * We'll prevent this by introducing upper limit.
303 	 * XXX: this mechanism may introduce another problem about
304 	 *      mutual exclusion of the variable CALLED, especially if we
305 	 *      use kernel thread.
306 	 */
307 	if (++called > max_gif_nesting) {
308 		log(LOG_NOTICE,
309 		    "gif_output: recursively called too many times(%d)\n",
310 		    called);
311 		m_freem(m);
312 		error = EIO;	/* is there better errno? */
313 		goto end;
314 	}
315 
316 	m->m_flags &= ~(M_BCAST|M_MCAST);
317 	if (!(ifp->if_flags & IFF_UP) ||
318 	    sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
319 		m_freem(m);
320 		error = ENETDOWN;
321 		goto end;
322 	}
323 
324 	if (ifp->if_bpf) {
325 		/*
326 		 * We need to prepend the address family as
327 		 * a four byte field.
328 		 */
329 		uint32_t af = dst->sa_family;
330 
331 		bpf_ptap(ifp->if_bpf, m, &af, sizeof(4));
332 	}
333 	ifp->if_opackets++;
334 	ifp->if_obytes += m->m_pkthdr.len;
335 
336 	/* inner AF-specific encapsulation */
337 
338 	/* XXX should we check if our outer source is legal? */
339 
340 	/* dispatch to output logic based on outer AF */
341 	switch (sc->gif_psrc->sa_family) {
342 #ifdef INET
343 	case AF_INET:
344 		error = in_gif_output(ifp, dst->sa_family, m);
345 		break;
346 #endif
347 #ifdef INET6
348 	case AF_INET6:
349 		error = in6_gif_output(ifp, dst->sa_family, m);
350 		break;
351 #endif
352 	default:
353 		m_freem(m);
354 		error = ENETDOWN;
355 		goto end;
356 	}
357 
358   end:
359 	called = 0;		/* reset recursion counter */
360 	if (error)
361 		ifp->if_oerrors++;
362 	return error;
363 }
364 
365 void
366 gif_input(struct mbuf *m, int af, struct ifnet *ifp)
367 {
368 	int isr;
369 
370 	if (ifp == NULL) {
371 		/* just in case */
372 		m_freem(m);
373 		return;
374 	}
375 
376 	m->m_pkthdr.rcvif = ifp;
377 
378 	if (ifp->if_bpf) {
379 		/*
380 		 * We need to prepend the address family as
381 		 * a four byte field.
382 		 */
383 		uint32_t af1 = af;
384 
385 		bpf_ptap(ifp->if_bpf, m, &af1, sizeof(af1));
386 	}
387 
388 	/*
389 	 * Put the packet to the network layer input queue according to the
390 	 * specified address family.
391 	 * Note: older versions of gif_input directly called network layer
392 	 * input functions, e.g. ip6_input, here.  We changed the policy to
393 	 * prevent too many recursive calls of such input functions, which
394 	 * might cause kernel panic.  But the change may introduce another
395 	 * problem; if the input queue is full, packets are discarded.
396 	 * The kernel stack overflow really happened, and we believed
397 	 * queue-full rarely occurs, so we changed the policy.
398 	 */
399 	switch (af) {
400 #ifdef INET
401 	case AF_INET:
402 		isr = NETISR_IP;
403 		break;
404 #endif
405 #ifdef INET6
406 	case AF_INET6:
407 		isr = NETISR_IPV6;
408 		break;
409 #endif
410 	default:
411 		m_freem(m);
412 		return;
413 	}
414 
415 	ifp->if_ipackets++;
416 	ifp->if_ibytes += m->m_pkthdr.len;
417 	netisr_dispatch(isr, m);
418 
419 	return;
420 }
421 
422 /* XXX how should we handle IPv6 scope on SIOC[GS]IFPHYADDR? */
423 int
424 gif_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data, struct ucred *cr)
425 {
426 	struct gif_softc *sc  = (struct gif_softc*)ifp;
427 	struct ifreq     *ifr = (struct ifreq*)data;
428 	int error = 0, size;
429 	struct sockaddr *dst, *src;
430 #ifdef	SIOCSIFMTU /* xxx */
431 	u_long mtu;
432 #endif
433 
434 	switch (cmd) {
435 	case SIOCSIFADDR:
436 		ifp->if_flags |= IFF_UP;
437 		break;
438 
439 	case SIOCSIFDSTADDR:
440 		break;
441 
442 	case SIOCADDMULTI:
443 	case SIOCDELMULTI:
444 		break;
445 
446 #ifdef	SIOCSIFMTU /* xxx */
447 	case SIOCGIFMTU:
448 		break;
449 
450 	case SIOCSIFMTU:
451 		mtu = ifr->ifr_mtu;
452 		if (mtu < GIF_MTU_MIN || mtu > GIF_MTU_MAX)
453 			return (EINVAL);
454 		ifp->if_mtu = mtu;
455 		break;
456 #endif /* SIOCSIFMTU */
457 
458 #ifdef INET
459 	case SIOCSIFPHYADDR:
460 #endif
461 #ifdef INET6
462 	case SIOCSIFPHYADDR_IN6:
463 #endif /* INET6 */
464 	case SIOCSLIFPHYADDR:
465 		switch (cmd) {
466 #ifdef INET
467 		case SIOCSIFPHYADDR:
468 			src = (struct sockaddr *)
469 				&(((struct in_aliasreq *)data)->ifra_addr);
470 			dst = (struct sockaddr *)
471 				&(((struct in_aliasreq *)data)->ifra_dstaddr);
472 			break;
473 #endif
474 #ifdef INET6
475 		case SIOCSIFPHYADDR_IN6:
476 			src = (struct sockaddr *)
477 				&(((struct in6_aliasreq *)data)->ifra_addr);
478 			dst = (struct sockaddr *)
479 				&(((struct in6_aliasreq *)data)->ifra_dstaddr);
480 			break;
481 #endif
482 		case SIOCSLIFPHYADDR:
483 			src = (struct sockaddr *)
484 				&(((struct if_laddrreq *)data)->addr);
485 			dst = (struct sockaddr *)
486 				&(((struct if_laddrreq *)data)->dstaddr);
487 			break;
488 		default:
489 			return EINVAL;
490 		}
491 
492 		/* sa_family must be equal */
493 		if (src->sa_family != dst->sa_family)
494 			return EINVAL;
495 
496 		/* validate sa_len */
497 		switch (src->sa_family) {
498 #ifdef INET
499 		case AF_INET:
500 			if (src->sa_len != sizeof(struct sockaddr_in))
501 				return EINVAL;
502 			break;
503 #endif
504 #ifdef INET6
505 		case AF_INET6:
506 			if (src->sa_len != sizeof(struct sockaddr_in6))
507 				return EINVAL;
508 			break;
509 #endif
510 		default:
511 			return EAFNOSUPPORT;
512 		}
513 		switch (dst->sa_family) {
514 #ifdef INET
515 		case AF_INET:
516 			if (dst->sa_len != sizeof(struct sockaddr_in))
517 				return EINVAL;
518 			break;
519 #endif
520 #ifdef INET6
521 		case AF_INET6:
522 			if (dst->sa_len != sizeof(struct sockaddr_in6))
523 				return EINVAL;
524 			break;
525 #endif
526 		default:
527 			return EAFNOSUPPORT;
528 		}
529 
530 		/* check sa_family looks sane for the cmd */
531 		switch (cmd) {
532 		case SIOCSIFPHYADDR:
533 			if (src->sa_family == AF_INET)
534 				break;
535 			return EAFNOSUPPORT;
536 #ifdef INET6
537 		case SIOCSIFPHYADDR_IN6:
538 			if (src->sa_family == AF_INET6)
539 				break;
540 			return EAFNOSUPPORT;
541 #endif /* INET6 */
542 		case SIOCSLIFPHYADDR:
543 			/* checks done in the above */
544 			break;
545 		}
546 
547 		error = gif_set_tunnel(&sc->gif_if, src, dst);
548 		break;
549 
550 #ifdef SIOCDIFPHYADDR
551 	case SIOCDIFPHYADDR:
552 		gif_delete_tunnel(&sc->gif_if);
553 		break;
554 #endif
555 
556 	case SIOCGIFPSRCADDR:
557 #ifdef INET6
558 	case SIOCGIFPSRCADDR_IN6:
559 #endif /* INET6 */
560 		if (sc->gif_psrc == NULL) {
561 			error = EADDRNOTAVAIL;
562 			goto bad;
563 		}
564 		src = sc->gif_psrc;
565 		switch (cmd) {
566 #ifdef INET
567 		case SIOCGIFPSRCADDR:
568 			dst = &ifr->ifr_addr;
569 			size = sizeof(ifr->ifr_addr);
570 			break;
571 #endif /* INET */
572 #ifdef INET6
573 		case SIOCGIFPSRCADDR_IN6:
574 			dst = (struct sockaddr *)
575 				&(((struct in6_ifreq *)data)->ifr_addr);
576 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
577 			break;
578 #endif /* INET6 */
579 		default:
580 			error = EADDRNOTAVAIL;
581 			goto bad;
582 		}
583 		if (src->sa_len > size)
584 			return EINVAL;
585 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
586 		break;
587 
588 	case SIOCGIFPDSTADDR:
589 #ifdef INET6
590 	case SIOCGIFPDSTADDR_IN6:
591 #endif /* INET6 */
592 		if (sc->gif_pdst == NULL) {
593 			error = EADDRNOTAVAIL;
594 			goto bad;
595 		}
596 		src = sc->gif_pdst;
597 		switch (cmd) {
598 #ifdef INET
599 		case SIOCGIFPDSTADDR:
600 			dst = &ifr->ifr_addr;
601 			size = sizeof(ifr->ifr_addr);
602 			break;
603 #endif /* INET */
604 #ifdef INET6
605 		case SIOCGIFPDSTADDR_IN6:
606 			dst = (struct sockaddr *)
607 				&(((struct in6_ifreq *)data)->ifr_addr);
608 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
609 			break;
610 #endif /* INET6 */
611 		default:
612 			error = EADDRNOTAVAIL;
613 			goto bad;
614 		}
615 		if (src->sa_len > size)
616 			return EINVAL;
617 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
618 		break;
619 
620 	case SIOCGLIFPHYADDR:
621 		if (sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
622 			error = EADDRNOTAVAIL;
623 			goto bad;
624 		}
625 
626 		/* copy src */
627 		src = sc->gif_psrc;
628 		dst = (struct sockaddr *)
629 			&(((struct if_laddrreq *)data)->addr);
630 		size = sizeof(((struct if_laddrreq *)data)->addr);
631 		if (src->sa_len > size)
632 			return EINVAL;
633 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
634 
635 		/* copy dst */
636 		src = sc->gif_pdst;
637 		dst = (struct sockaddr *)
638 			&(((struct if_laddrreq *)data)->dstaddr);
639 		size = sizeof(((struct if_laddrreq *)data)->dstaddr);
640 		if (src->sa_len > size)
641 			return EINVAL;
642 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
643 		break;
644 
645 	case SIOCSIFFLAGS:
646 		/* if_ioctl() takes care of it */
647 		break;
648 
649 	default:
650 		error = EINVAL;
651 		break;
652 	}
653  bad:
654 	return error;
655 }
656 
657 int
658 gif_set_tunnel(struct ifnet *ifp, struct sockaddr *src, struct sockaddr *dst)
659 {
660 	struct gif_softc *sc = (struct gif_softc *)ifp;
661 	struct gif_softc *sc2;
662 	struct sockaddr *osrc, *odst, *sa;
663 	int error = 0;
664 
665 	crit_enter();
666 
667 	LIST_FOREACH(sc2, &gif_softc_list, gif_list) {
668 		if (sc2 == sc)
669 			continue;
670 		if (!sc2->gif_pdst || !sc2->gif_psrc)
671 			continue;
672 		if (sc2->gif_pdst->sa_family != dst->sa_family ||
673 		    sc2->gif_pdst->sa_len != dst->sa_len ||
674 		    sc2->gif_psrc->sa_family != src->sa_family ||
675 		    sc2->gif_psrc->sa_len != src->sa_len)
676 			continue;
677 
678 		/*
679 		 * Disallow parallel tunnels unless instructed
680 		 * otherwise.
681 		 */
682 		if (!parallel_tunnels &&
683 		    bcmp(sc2->gif_pdst, dst, dst->sa_len) == 0 &&
684 		    bcmp(sc2->gif_psrc, src, src->sa_len) == 0) {
685 			error = EADDRNOTAVAIL;
686 			goto bad;
687 		}
688 
689 		/* XXX both end must be valid? (I mean, not 0.0.0.0) */
690 	}
691 
692 	/* XXX we can detach from both, but be polite just in case */
693 	if (sc->gif_psrc)
694 		switch (sc->gif_psrc->sa_family) {
695 #ifdef INET
696 		case AF_INET:
697 			(void)in_gif_detach(sc);
698 			break;
699 #endif
700 #ifdef INET6
701 		case AF_INET6:
702 			(void)in6_gif_detach(sc);
703 			break;
704 #endif
705 		}
706 
707 	osrc = sc->gif_psrc;
708 	sa = (struct sockaddr *)malloc(src->sa_len, M_IFADDR, M_WAITOK);
709 	bcopy((caddr_t)src, (caddr_t)sa, src->sa_len);
710 	sc->gif_psrc = sa;
711 
712 	odst = sc->gif_pdst;
713 	sa = (struct sockaddr *)malloc(dst->sa_len, M_IFADDR, M_WAITOK);
714 	bcopy((caddr_t)dst, (caddr_t)sa, dst->sa_len);
715 	sc->gif_pdst = sa;
716 
717 	switch (sc->gif_psrc->sa_family) {
718 #ifdef INET
719 	case AF_INET:
720 		error = in_gif_attach(sc);
721 		break;
722 #endif
723 #ifdef INET6
724 	case AF_INET6:
725 		error = in6_gif_attach(sc);
726 		break;
727 #endif
728 	}
729 	if (error) {
730 		/* rollback */
731 		free((caddr_t)sc->gif_psrc, M_IFADDR);
732 		free((caddr_t)sc->gif_pdst, M_IFADDR);
733 		sc->gif_psrc = osrc;
734 		sc->gif_pdst = odst;
735 		goto bad;
736 	}
737 
738 	if (osrc)
739 		free((caddr_t)osrc, M_IFADDR);
740 	if (odst)
741 		free((caddr_t)odst, M_IFADDR);
742 
743 	if (sc->gif_psrc && sc->gif_pdst)
744 		ifp->if_flags |= IFF_RUNNING;
745 	else
746 		ifp->if_flags &= ~IFF_RUNNING;
747 	crit_exit();
748 
749 	return 0;
750 
751  bad:
752 	if (sc->gif_psrc && sc->gif_pdst)
753 		ifp->if_flags |= IFF_RUNNING;
754 	else
755 		ifp->if_flags &= ~IFF_RUNNING;
756 	crit_exit();
757 
758 	return error;
759 }
760 
761 void
762 gif_delete_tunnel(struct ifnet *ifp)
763 {
764 	struct gif_softc *sc = (struct gif_softc *)ifp;
765 
766 	crit_enter();
767 
768 	if (sc->gif_psrc) {
769 		free((caddr_t)sc->gif_psrc, M_IFADDR);
770 		sc->gif_psrc = NULL;
771 	}
772 	if (sc->gif_pdst) {
773 		free((caddr_t)sc->gif_pdst, M_IFADDR);
774 		sc->gif_pdst = NULL;
775 	}
776 	/* it is safe to detach from both */
777 #ifdef INET
778 	(void)in_gif_detach(sc);
779 #endif
780 #ifdef INET6
781 	(void)in6_gif_detach(sc);
782 #endif
783 
784 	if (sc->gif_psrc && sc->gif_pdst)
785 		ifp->if_flags |= IFF_RUNNING;
786 	else
787 		ifp->if_flags &= ~IFF_RUNNING;
788 	crit_exit();
789 }
790