xref: /dragonfly/sys/net/gif/if_gif.c (revision f02303f9) 
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 1.18 2006/10/25 20:56:02 dillon 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/bus.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 <sys/thread2.h>
52 
53 #include <machine/cpu.h>
54 
55 #include <net/if.h>
56 #include <net/if_types.h>
57 #include <net/netisr.h>
58 #include <net/route.h>
59 #include <net/bpf.h>
60 
61 #include <netinet/in.h>
62 #include <netinet/in_systm.h>
63 #include <netinet/ip.h>
64 #ifdef	INET
65 #include <netinet/in_var.h>
66 #include <netinet/in_gif.h>
67 #include <netinet/ip_var.h>
68 #endif	/* INET */
69 
70 #ifdef INET6
71 #ifndef INET
72 #include <netinet/in.h>
73 #endif
74 #include <netinet6/in6_var.h>
75 #include <netinet/ip6.h>
76 #include <netinet6/ip6_var.h>
77 #include <netinet6/in6_gif.h>
78 #include <netinet6/ip6protosw.h>
79 #endif /* INET6 */
80 
81 #include <netinet/ip_encap.h>
82 #include "if_gif.h"
83 
84 #include <net/net_osdep.h>
85 
86 #define GIFNAME		"gif"
87 
88 static MALLOC_DEFINE(M_GIF, "gif", "Generic Tunnel Interface");
89 LIST_HEAD(, gif_softc) gif_softc_list;
90 
91 int	gif_clone_create (struct if_clone *, int);
92 void	gif_clone_destroy (struct ifnet *);
93 
94 struct if_clone gif_cloner = IF_CLONE_INITIALIZER("gif", gif_clone_create,
95     gif_clone_destroy, 0, IF_MAXUNIT);
96 
97 static int gifmodevent (module_t, int, void *);
98 
99 SYSCTL_DECL(_net_link);
100 SYSCTL_NODE(_net_link, IFT_GIF, gif, CTLFLAG_RW, 0,
101     "Generic Tunnel Interface");
102 #ifndef MAX_GIF_NEST
103 /*
104  * This macro controls the default upper limitation on nesting of gif tunnels.
105  * Since, setting a large value to this macro with a careless configuration
106  * may introduce system crash, we don't allow any nestings by default.
107  * If you need to configure nested gif tunnels, you can define this macro
108  * in your kernel configuration file.  However, if you do so, please be
109  * careful to configure the tunnels so that it won't make a loop.
110  */
111 #define MAX_GIF_NEST 1
112 #endif
113 static int max_gif_nesting = MAX_GIF_NEST;
114 SYSCTL_INT(_net_link_gif, OID_AUTO, max_nesting, CTLFLAG_RW,
115     &max_gif_nesting, 0, "Max nested tunnels");
116 
117 /*
118  * By default, we disallow creation of multiple tunnels between the same
119  * pair of addresses.  Some applications require this functionality so
120  * we allow control over this check here.
121  */
122 #ifdef XBONEHACK
123 static int parallel_tunnels = 1;
124 #else
125 static int parallel_tunnels = 0;
126 #endif
127 SYSCTL_INT(_net_link_gif, OID_AUTO, parallel_tunnels, CTLFLAG_RW,
128     &parallel_tunnels, 0, "Allow parallel tunnels?");
129 
130 int
131 gif_clone_create(struct if_clone *ifc, int unit)
132 {
133 	struct gif_softc *sc;
134 
135 	sc = kmalloc (sizeof(struct gif_softc), M_GIF, M_WAITOK);
136 	bzero(sc, sizeof(struct gif_softc));
137 
138 	sc->gif_if.if_softc = sc;
139 	if_initname(&(sc->gif_if), GIFNAME, unit);
140 
141 	gifattach0(sc);
142 
143 	LIST_INSERT_HEAD(&gif_softc_list, sc, gif_list);
144 	return (0);
145 }
146 
147 void
148 gifattach0(struct gif_softc *sc)
149 {
150 
151 	sc->encap_cookie4 = sc->encap_cookie6 = NULL;
152 
153 	sc->gif_if.if_addrlen = 0;
154 	sc->gif_if.if_mtu    = GIF_MTU;
155 	sc->gif_if.if_flags  = IFF_POINTOPOINT | IFF_MULTICAST;
156 #if 0
157 	/* turn off ingress filter */
158 	sc->gif_if.if_flags  |= IFF_LINK2;
159 #endif
160 	sc->gif_if.if_ioctl  = gif_ioctl;
161 	sc->gif_if.if_output = gif_output;
162 	sc->gif_if.if_type   = IFT_GIF;
163 	sc->gif_if.if_snd.ifq_maxlen = IFQ_MAXLEN;
164 	if_attach(&sc->gif_if, NULL);
165 	bpfattach(&sc->gif_if, DLT_NULL, sizeof(u_int));
166 }
167 
168 void
169 gif_clone_destroy(struct ifnet *ifp)
170 {
171 	int err;
172 	struct gif_softc *sc = ifp->if_softc;
173 
174 	gif_delete_tunnel(&sc->gif_if);
175 	LIST_REMOVE(sc, gif_list);
176 #ifdef INET6
177 	if (sc->encap_cookie6 != NULL) {
178 		err = encap_detach(sc->encap_cookie6);
179 		KASSERT(err == 0, ("Unexpected error detaching encap_cookie6"));
180 	}
181 #endif
182 #ifdef INET
183 	if (sc->encap_cookie4 != NULL) {
184 		err = encap_detach(sc->encap_cookie4);
185 		KASSERT(err == 0, ("Unexpected error detaching encap_cookie4"));
186 	}
187 #endif
188 
189 	bpfdetach(ifp);
190 	if_detach(ifp);
191 
192 	kfree(sc, M_GIF);
193 }
194 
195 static int
196 gifmodevent(module_t mod, int type, void *data)
197 {
198 
199 	switch (type) {
200 	case MOD_LOAD:
201 		LIST_INIT(&gif_softc_list);
202 		if_clone_attach(&gif_cloner);
203 
204 #ifdef INET6
205 		ip6_gif_hlim = GIF_HLIM;
206 #endif
207 
208 		break;
209 	case MOD_UNLOAD:
210 		if_clone_detach(&gif_cloner);
211 
212 		while (!LIST_EMPTY(&gif_softc_list))
213 			gif_clone_destroy(&LIST_FIRST(&gif_softc_list)->gif_if);
214 
215 #ifdef INET6
216 		ip6_gif_hlim = 0;
217 #endif
218 		break;
219 	}
220 	return 0;
221 }
222 
223 static moduledata_t gif_mod = {
224 	"if_gif",
225 	gifmodevent,
226 	0
227 };
228 
229 DECLARE_MODULE(if_gif, gif_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
230 
231 int
232 gif_encapcheck(const struct mbuf *m, int off, int proto, void *arg)
233 {
234 	struct ip ip;
235 	struct gif_softc *sc;
236 
237 	sc = (struct gif_softc *)arg;
238 	if (sc == NULL)
239 		return 0;
240 
241 	if ((sc->gif_if.if_flags & IFF_UP) == 0)
242 		return 0;
243 
244 	/* no physical address */
245 	if (!sc->gif_psrc || !sc->gif_pdst)
246 		return 0;
247 
248 	switch (proto) {
249 #ifdef INET
250 	case IPPROTO_IPV4:
251 		break;
252 #endif
253 #ifdef INET6
254 	case IPPROTO_IPV6:
255 		break;
256 #endif
257 	default:
258 		return 0;
259 	}
260 
261 	/* Bail on short packets */
262 	if (m->m_pkthdr.len < sizeof(ip))
263 		return 0;
264 
265 	m_copydata(m, 0, sizeof(ip), (caddr_t)&ip);
266 
267 	switch (ip.ip_v) {
268 #ifdef INET
269 	case 4:
270 		if (sc->gif_psrc->sa_family != AF_INET ||
271 		    sc->gif_pdst->sa_family != AF_INET)
272 			return 0;
273 		return gif_encapcheck4(m, off, proto, arg);
274 #endif
275 #ifdef INET6
276 	case 6:
277 		if (m->m_pkthdr.len < sizeof(struct ip6_hdr))
278 			return 0;
279 		if (sc->gif_psrc->sa_family != AF_INET6 ||
280 		    sc->gif_pdst->sa_family != AF_INET6)
281 			return 0;
282 		return gif_encapcheck6(m, off, proto, arg);
283 #endif
284 	default:
285 		return 0;
286 	}
287 }
288 
289 /*
290  * Parameters:
291  *	rt:	added in net2
292  */
293 int
294 gif_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
295 	   struct rtentry *rt)
296 {
297 	struct gif_softc *sc = (struct gif_softc*)ifp;
298 	int error = 0;
299 	static int called = 0;	/* XXX: MUTEX */
300 
301 	/*
302 	 * gif may cause infinite recursion calls when misconfigured.
303 	 * We'll prevent this by introducing upper limit.
304 	 * XXX: this mechanism may introduce another problem about
305 	 *      mutual exclusion of the variable CALLED, especially if we
306 	 *      use kernel thread.
307 	 */
308 	if (++called > max_gif_nesting) {
309 		log(LOG_NOTICE,
310 		    "gif_output: recursively called too many times(%d)\n",
311 		    called);
312 		m_freem(m);
313 		error = EIO;	/* is there better errno? */
314 		goto end;
315 	}
316 
317 	m->m_flags &= ~(M_BCAST|M_MCAST);
318 	if (!(ifp->if_flags & IFF_UP) ||
319 	    sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
320 		m_freem(m);
321 		error = ENETDOWN;
322 		goto end;
323 	}
324 
325 	if (ifp->if_bpf) {
326 		/*
327 		 * We need to prepend the address family as
328 		 * a four byte field.
329 		 */
330 		uint32_t af = dst->sa_family;
331 
332 		bpf_ptap(ifp->if_bpf, m, &af, sizeof(4));
333 	}
334 	ifp->if_opackets++;
335 	ifp->if_obytes += m->m_pkthdr.len;
336 
337 	/* inner AF-specific encapsulation */
338 
339 	/* XXX should we check if our outer source is legal? */
340 
341 	/* dispatch to output logic based on outer AF */
342 	switch (sc->gif_psrc->sa_family) {
343 #ifdef INET
344 	case AF_INET:
345 		error = in_gif_output(ifp, dst->sa_family, m);
346 		break;
347 #endif
348 #ifdef INET6
349 	case AF_INET6:
350 		error = in6_gif_output(ifp, dst->sa_family, m);
351 		break;
352 #endif
353 	default:
354 		m_freem(m);
355 		error = ENETDOWN;
356 		goto end;
357 	}
358 
359   end:
360 	called = 0;		/* reset recursion counter */
361 	if (error)
362 		ifp->if_oerrors++;
363 	return error;
364 }
365 
366 void
367 gif_input(struct mbuf *m, int af, struct ifnet *ifp)
368 {
369 	int isr;
370 
371 	if (ifp == NULL) {
372 		/* just in case */
373 		m_freem(m);
374 		return;
375 	}
376 
377 	m->m_pkthdr.rcvif = ifp;
378 
379 	if (ifp->if_bpf) {
380 		/*
381 		 * We need to prepend the address family as
382 		 * a four byte field.
383 		 */
384 		uint32_t af1 = af;
385 
386 		bpf_ptap(ifp->if_bpf, m, &af1, sizeof(af1));
387 	}
388 
389 	/*
390 	 * Put the packet to the network layer input queue according to the
391 	 * specified address family.
392 	 * Note: older versions of gif_input directly called network layer
393 	 * input functions, e.g. ip6_input, here.  We changed the policy to
394 	 * prevent too many recursive calls of such input functions, which
395 	 * might cause kernel panic.  But the change may introduce another
396 	 * problem; if the input queue is full, packets are discarded.
397 	 * The kernel stack overflow really happened, and we believed
398 	 * queue-full rarely occurs, so we changed the policy.
399 	 */
400 	switch (af) {
401 #ifdef INET
402 	case AF_INET:
403 		isr = NETISR_IP;
404 		break;
405 #endif
406 #ifdef INET6
407 	case AF_INET6:
408 		isr = NETISR_IPV6;
409 		break;
410 #endif
411 	default:
412 		m_freem(m);
413 		return;
414 	}
415 
416 	ifp->if_ipackets++;
417 	ifp->if_ibytes += m->m_pkthdr.len;
418 	netisr_dispatch(isr, m);
419 
420 	return;
421 }
422 
423 /* XXX how should we handle IPv6 scope on SIOC[GS]IFPHYADDR? */
424 int
425 gif_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data, struct ucred *cr)
426 {
427 	struct gif_softc *sc  = (struct gif_softc*)ifp;
428 	struct ifreq     *ifr = (struct ifreq*)data;
429 	int error = 0, size;
430 	struct sockaddr *dst, *src;
431 #ifdef	SIOCSIFMTU /* xxx */
432 	u_long mtu;
433 #endif
434 
435 	switch (cmd) {
436 	case SIOCSIFADDR:
437 		ifp->if_flags |= IFF_UP;
438 		break;
439 
440 	case SIOCSIFDSTADDR:
441 		break;
442 
443 	case SIOCADDMULTI:
444 	case SIOCDELMULTI:
445 		break;
446 
447 #ifdef	SIOCSIFMTU /* xxx */
448 	case SIOCGIFMTU:
449 		break;
450 
451 	case SIOCSIFMTU:
452 		mtu = ifr->ifr_mtu;
453 		if (mtu < GIF_MTU_MIN || mtu > GIF_MTU_MAX)
454 			return (EINVAL);
455 		ifp->if_mtu = mtu;
456 		break;
457 #endif /* SIOCSIFMTU */
458 
459 #ifdef INET
460 	case SIOCSIFPHYADDR:
461 #endif
462 #ifdef INET6
463 	case SIOCSIFPHYADDR_IN6:
464 #endif /* INET6 */
465 	case SIOCSLIFPHYADDR:
466 		switch (cmd) {
467 #ifdef INET
468 		case SIOCSIFPHYADDR:
469 			src = (struct sockaddr *)
470 				&(((struct in_aliasreq *)data)->ifra_addr);
471 			dst = (struct sockaddr *)
472 				&(((struct in_aliasreq *)data)->ifra_dstaddr);
473 			break;
474 #endif
475 #ifdef INET6
476 		case SIOCSIFPHYADDR_IN6:
477 			src = (struct sockaddr *)
478 				&(((struct in6_aliasreq *)data)->ifra_addr);
479 			dst = (struct sockaddr *)
480 				&(((struct in6_aliasreq *)data)->ifra_dstaddr);
481 			break;
482 #endif
483 		case SIOCSLIFPHYADDR:
484 			src = (struct sockaddr *)
485 				&(((struct if_laddrreq *)data)->addr);
486 			dst = (struct sockaddr *)
487 				&(((struct if_laddrreq *)data)->dstaddr);
488 			break;
489 		default:
490 			return EINVAL;
491 		}
492 
493 		/* sa_family must be equal */
494 		if (src->sa_family != dst->sa_family)
495 			return EINVAL;
496 
497 		/* validate sa_len */
498 		switch (src->sa_family) {
499 #ifdef INET
500 		case AF_INET:
501 			if (src->sa_len != sizeof(struct sockaddr_in))
502 				return EINVAL;
503 			break;
504 #endif
505 #ifdef INET6
506 		case AF_INET6:
507 			if (src->sa_len != sizeof(struct sockaddr_in6))
508 				return EINVAL;
509 			break;
510 #endif
511 		default:
512 			return EAFNOSUPPORT;
513 		}
514 		switch (dst->sa_family) {
515 #ifdef INET
516 		case AF_INET:
517 			if (dst->sa_len != sizeof(struct sockaddr_in))
518 				return EINVAL;
519 			break;
520 #endif
521 #ifdef INET6
522 		case AF_INET6:
523 			if (dst->sa_len != sizeof(struct sockaddr_in6))
524 				return EINVAL;
525 			break;
526 #endif
527 		default:
528 			return EAFNOSUPPORT;
529 		}
530 
531 		/* check sa_family looks sane for the cmd */
532 		switch (cmd) {
533 		case SIOCSIFPHYADDR:
534 			if (src->sa_family == AF_INET)
535 				break;
536 			return EAFNOSUPPORT;
537 #ifdef INET6
538 		case SIOCSIFPHYADDR_IN6:
539 			if (src->sa_family == AF_INET6)
540 				break;
541 			return EAFNOSUPPORT;
542 #endif /* INET6 */
543 		case SIOCSLIFPHYADDR:
544 			/* checks done in the above */
545 			break;
546 		}
547 
548 		error = gif_set_tunnel(&sc->gif_if, src, dst);
549 		break;
550 
551 #ifdef SIOCDIFPHYADDR
552 	case SIOCDIFPHYADDR:
553 		gif_delete_tunnel(&sc->gif_if);
554 		break;
555 #endif
556 
557 	case SIOCGIFPSRCADDR:
558 #ifdef INET6
559 	case SIOCGIFPSRCADDR_IN6:
560 #endif /* INET6 */
561 		if (sc->gif_psrc == NULL) {
562 			error = EADDRNOTAVAIL;
563 			goto bad;
564 		}
565 		src = sc->gif_psrc;
566 		switch (cmd) {
567 #ifdef INET
568 		case SIOCGIFPSRCADDR:
569 			dst = &ifr->ifr_addr;
570 			size = sizeof(ifr->ifr_addr);
571 			break;
572 #endif /* INET */
573 #ifdef INET6
574 		case SIOCGIFPSRCADDR_IN6:
575 			dst = (struct sockaddr *)
576 				&(((struct in6_ifreq *)data)->ifr_addr);
577 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
578 			break;
579 #endif /* INET6 */
580 		default:
581 			error = EADDRNOTAVAIL;
582 			goto bad;
583 		}
584 		if (src->sa_len > size)
585 			return EINVAL;
586 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
587 		break;
588 
589 	case SIOCGIFPDSTADDR:
590 #ifdef INET6
591 	case SIOCGIFPDSTADDR_IN6:
592 #endif /* INET6 */
593 		if (sc->gif_pdst == NULL) {
594 			error = EADDRNOTAVAIL;
595 			goto bad;
596 		}
597 		src = sc->gif_pdst;
598 		switch (cmd) {
599 #ifdef INET
600 		case SIOCGIFPDSTADDR:
601 			dst = &ifr->ifr_addr;
602 			size = sizeof(ifr->ifr_addr);
603 			break;
604 #endif /* INET */
605 #ifdef INET6
606 		case SIOCGIFPDSTADDR_IN6:
607 			dst = (struct sockaddr *)
608 				&(((struct in6_ifreq *)data)->ifr_addr);
609 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
610 			break;
611 #endif /* INET6 */
612 		default:
613 			error = EADDRNOTAVAIL;
614 			goto bad;
615 		}
616 		if (src->sa_len > size)
617 			return EINVAL;
618 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
619 		break;
620 
621 	case SIOCGLIFPHYADDR:
622 		if (sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
623 			error = EADDRNOTAVAIL;
624 			goto bad;
625 		}
626 
627 		/* copy src */
628 		src = sc->gif_psrc;
629 		dst = (struct sockaddr *)
630 			&(((struct if_laddrreq *)data)->addr);
631 		size = sizeof(((struct if_laddrreq *)data)->addr);
632 		if (src->sa_len > size)
633 			return EINVAL;
634 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
635 
636 		/* copy dst */
637 		src = sc->gif_pdst;
638 		dst = (struct sockaddr *)
639 			&(((struct if_laddrreq *)data)->dstaddr);
640 		size = sizeof(((struct if_laddrreq *)data)->dstaddr);
641 		if (src->sa_len > size)
642 			return EINVAL;
643 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
644 		break;
645 
646 	case SIOCSIFFLAGS:
647 		/* if_ioctl() takes care of it */
648 		break;
649 
650 	default:
651 		error = EINVAL;
652 		break;
653 	}
654  bad:
655 	return error;
656 }
657 
658 int
659 gif_set_tunnel(struct ifnet *ifp, struct sockaddr *src, struct sockaddr *dst)
660 {
661 	struct gif_softc *sc = (struct gif_softc *)ifp;
662 	struct gif_softc *sc2;
663 	struct sockaddr *osrc, *odst, *sa;
664 	int error = 0;
665 
666 	crit_enter();
667 
668 	LIST_FOREACH(sc2, &gif_softc_list, gif_list) {
669 		if (sc2 == sc)
670 			continue;
671 		if (!sc2->gif_pdst || !sc2->gif_psrc)
672 			continue;
673 		if (sc2->gif_pdst->sa_family != dst->sa_family ||
674 		    sc2->gif_pdst->sa_len != dst->sa_len ||
675 		    sc2->gif_psrc->sa_family != src->sa_family ||
676 		    sc2->gif_psrc->sa_len != src->sa_len)
677 			continue;
678 
679 		/*
680 		 * Disallow parallel tunnels unless instructed
681 		 * otherwise.
682 		 */
683 		if (!parallel_tunnels &&
684 		    bcmp(sc2->gif_pdst, dst, dst->sa_len) == 0 &&
685 		    bcmp(sc2->gif_psrc, src, src->sa_len) == 0) {
686 			error = EADDRNOTAVAIL;
687 			goto bad;
688 		}
689 
690 		/* XXX both end must be valid? (I mean, not 0.0.0.0) */
691 	}
692 
693 	/* XXX we can detach from both, but be polite just in case */
694 	if (sc->gif_psrc)
695 		switch (sc->gif_psrc->sa_family) {
696 #ifdef INET
697 		case AF_INET:
698 			in_gif_detach(sc);
699 			break;
700 #endif
701 #ifdef INET6
702 		case AF_INET6:
703 			in6_gif_detach(sc);
704 			break;
705 #endif
706 		}
707 
708 	osrc = sc->gif_psrc;
709 	sa = (struct sockaddr *)kmalloc(src->sa_len, M_IFADDR, M_WAITOK);
710 	bcopy((caddr_t)src, (caddr_t)sa, src->sa_len);
711 	sc->gif_psrc = sa;
712 
713 	odst = sc->gif_pdst;
714 	sa = (struct sockaddr *)kmalloc(dst->sa_len, M_IFADDR, M_WAITOK);
715 	bcopy((caddr_t)dst, (caddr_t)sa, dst->sa_len);
716 	sc->gif_pdst = sa;
717 
718 	switch (sc->gif_psrc->sa_family) {
719 #ifdef INET
720 	case AF_INET:
721 		error = in_gif_attach(sc);
722 		break;
723 #endif
724 #ifdef INET6
725 	case AF_INET6:
726 		error = in6_gif_attach(sc);
727 		break;
728 #endif
729 	}
730 	if (error) {
731 		/* rollback */
732 		kfree((caddr_t)sc->gif_psrc, M_IFADDR);
733 		kfree((caddr_t)sc->gif_pdst, M_IFADDR);
734 		sc->gif_psrc = osrc;
735 		sc->gif_pdst = odst;
736 		goto bad;
737 	}
738 
739 	if (osrc)
740 		kfree((caddr_t)osrc, M_IFADDR);
741 	if (odst)
742 		kfree((caddr_t)odst, M_IFADDR);
743 
744 	if (sc->gif_psrc && sc->gif_pdst)
745 		ifp->if_flags |= IFF_RUNNING;
746 	else
747 		ifp->if_flags &= ~IFF_RUNNING;
748 	crit_exit();
749 
750 	return 0;
751 
752  bad:
753 	if (sc->gif_psrc && sc->gif_pdst)
754 		ifp->if_flags |= IFF_RUNNING;
755 	else
756 		ifp->if_flags &= ~IFF_RUNNING;
757 	crit_exit();
758 
759 	return error;
760 }
761 
762 void
763 gif_delete_tunnel(struct ifnet *ifp)
764 {
765 	struct gif_softc *sc = (struct gif_softc *)ifp;
766 
767 	crit_enter();
768 
769 	if (sc->gif_psrc) {
770 		kfree((caddr_t)sc->gif_psrc, M_IFADDR);
771 		sc->gif_psrc = NULL;
772 	}
773 	if (sc->gif_pdst) {
774 		kfree((caddr_t)sc->gif_pdst, M_IFADDR);
775 		sc->gif_pdst = NULL;
776 	}
777 	/* it is safe to detach from both */
778 #ifdef INET
779 	in_gif_detach(sc);
780 #endif
781 #ifdef INET6
782 	in6_gif_detach(sc);
783 #endif
784 
785 	if (sc->gif_psrc && sc->gif_pdst)
786 		ifp->if_flags |= IFF_RUNNING;
787 	else
788 		ifp->if_flags &= ~IFF_RUNNING;
789 	crit_exit();
790 }
791