xref: /freebsd/sys/net/if_gif.c (revision f9218d3d4fd34f082473b3a021c6d4d109fb47cf)
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 	struct ifqueue *ifq = NULL;
409 
410 	if (ifp == NULL) {
411 		/* just in case */
412 		m_freem(m);
413 		return;
414 	}
415 
416 	m->m_pkthdr.rcvif = ifp;
417 
418 #ifdef MAC
419 	mac_create_mbuf_from_ifnet(ifp, m);
420 #endif
421 
422 	if (ifp->if_bpf) {
423 		/*
424 		 * We need to prepend the address family as
425 		 * a four byte field.  Cons up a dummy header
426 		 * to pacify bpf.  This is safe because bpf
427 		 * will only read from the mbuf (i.e., it won't
428 		 * try to free it or keep a pointer a to it).
429 		 */
430 		struct mbuf m0;
431 		u_int32_t af1 = af;
432 
433 		m0.m_next = m;
434 		m0.m_len = 4;
435 		m0.m_data = (char *)&af1;
436 
437 		BPF_MTAP(ifp, &m0);
438 	}
439 
440 	if (ng_gif_input_p != NULL) {
441 		(*ng_gif_input_p)(ifp, &m, af);
442 		if (m == NULL)
443 			return;
444 	}
445 
446 	/*
447 	 * Put the packet to the network layer input queue according to the
448 	 * specified address family.
449 	 * Note: older versions of gif_input directly called network layer
450 	 * input functions, e.g. ip6_input, here.  We changed the policy to
451 	 * prevent too many recursive calls of such input functions, which
452 	 * might cause kernel panic.  But the change may introduce another
453 	 * problem; if the input queue is full, packets are discarded.
454 	 * The kernel stack overflow really happened, and we believed
455 	 * queue-full rarely occurs, so we changed the policy.
456 	 */
457 	switch (af) {
458 #ifdef INET
459 	case AF_INET:
460 		ifq = &ipintrq;
461 		isr = NETISR_IP;
462 		break;
463 #endif
464 #ifdef INET6
465 	case AF_INET6:
466 		ifq = &ip6intrq;
467 		isr = NETISR_IPV6;
468 		break;
469 #endif
470 	default:
471 		if (ng_gif_input_orphan_p != NULL)
472 			(*ng_gif_input_orphan_p)(ifp, m, af);
473 		else
474 			m_freem(m);
475 		return;
476 	}
477 
478 	ifp->if_ipackets++;
479 	ifp->if_ibytes += m->m_pkthdr.len;
480 	(void) IF_HANDOFF(ifq, m, NULL);
481 	/* we need schednetisr since the address family may change */
482 	schednetisr(isr);
483 
484 	return;
485 }
486 
487 /* XXX how should we handle IPv6 scope on SIOC[GS]IFPHYADDR? */
488 int
489 gif_ioctl(ifp, cmd, data)
490 	struct ifnet *ifp;
491 	u_long cmd;
492 	caddr_t data;
493 {
494 	struct gif_softc *sc  = (struct gif_softc*)ifp;
495 	struct ifreq     *ifr = (struct ifreq*)data;
496 	int error = 0, size;
497 	struct sockaddr *dst, *src;
498 #ifdef	SIOCSIFMTU /* xxx */
499 	u_long mtu;
500 #endif
501 
502 	switch (cmd) {
503 	case SIOCSIFADDR:
504 		ifp->if_flags |= IFF_UP;
505 		break;
506 
507 	case SIOCSIFDSTADDR:
508 		break;
509 
510 	case SIOCADDMULTI:
511 	case SIOCDELMULTI:
512 		break;
513 
514 #ifdef	SIOCSIFMTU /* xxx */
515 	case SIOCGIFMTU:
516 		break;
517 
518 	case SIOCSIFMTU:
519 		mtu = ifr->ifr_mtu;
520 		if (mtu < GIF_MTU_MIN || mtu > GIF_MTU_MAX)
521 			return (EINVAL);
522 		ifp->if_mtu = mtu;
523 		break;
524 #endif /* SIOCSIFMTU */
525 
526 #ifdef INET
527 	case SIOCSIFPHYADDR:
528 #endif
529 #ifdef INET6
530 	case SIOCSIFPHYADDR_IN6:
531 #endif /* INET6 */
532 	case SIOCSLIFPHYADDR:
533 		switch (cmd) {
534 #ifdef INET
535 		case SIOCSIFPHYADDR:
536 			src = (struct sockaddr *)
537 				&(((struct in_aliasreq *)data)->ifra_addr);
538 			dst = (struct sockaddr *)
539 				&(((struct in_aliasreq *)data)->ifra_dstaddr);
540 			break;
541 #endif
542 #ifdef INET6
543 		case SIOCSIFPHYADDR_IN6:
544 			src = (struct sockaddr *)
545 				&(((struct in6_aliasreq *)data)->ifra_addr);
546 			dst = (struct sockaddr *)
547 				&(((struct in6_aliasreq *)data)->ifra_dstaddr);
548 			break;
549 #endif
550 		case SIOCSLIFPHYADDR:
551 			src = (struct sockaddr *)
552 				&(((struct if_laddrreq *)data)->addr);
553 			dst = (struct sockaddr *)
554 				&(((struct if_laddrreq *)data)->dstaddr);
555 			break;
556 		default:
557 			return EINVAL;
558 		}
559 
560 		/* sa_family must be equal */
561 		if (src->sa_family != dst->sa_family)
562 			return EINVAL;
563 
564 		/* validate sa_len */
565 		switch (src->sa_family) {
566 #ifdef INET
567 		case AF_INET:
568 			if (src->sa_len != sizeof(struct sockaddr_in))
569 				return EINVAL;
570 			break;
571 #endif
572 #ifdef INET6
573 		case AF_INET6:
574 			if (src->sa_len != sizeof(struct sockaddr_in6))
575 				return EINVAL;
576 			break;
577 #endif
578 		default:
579 			return EAFNOSUPPORT;
580 		}
581 		switch (dst->sa_family) {
582 #ifdef INET
583 		case AF_INET:
584 			if (dst->sa_len != sizeof(struct sockaddr_in))
585 				return EINVAL;
586 			break;
587 #endif
588 #ifdef INET6
589 		case AF_INET6:
590 			if (dst->sa_len != sizeof(struct sockaddr_in6))
591 				return EINVAL;
592 			break;
593 #endif
594 		default:
595 			return EAFNOSUPPORT;
596 		}
597 
598 		/* check sa_family looks sane for the cmd */
599 		switch (cmd) {
600 		case SIOCSIFPHYADDR:
601 			if (src->sa_family == AF_INET)
602 				break;
603 			return EAFNOSUPPORT;
604 #ifdef INET6
605 		case SIOCSIFPHYADDR_IN6:
606 			if (src->sa_family == AF_INET6)
607 				break;
608 			return EAFNOSUPPORT;
609 #endif /* INET6 */
610 		case SIOCSLIFPHYADDR:
611 			/* checks done in the above */
612 			break;
613 		}
614 
615 		error = gif_set_tunnel(&sc->gif_if, src, dst);
616 		break;
617 
618 #ifdef SIOCDIFPHYADDR
619 	case SIOCDIFPHYADDR:
620 		gif_delete_tunnel(&sc->gif_if);
621 		break;
622 #endif
623 
624 	case SIOCGIFPSRCADDR:
625 #ifdef INET6
626 	case SIOCGIFPSRCADDR_IN6:
627 #endif /* INET6 */
628 		if (sc->gif_psrc == NULL) {
629 			error = EADDRNOTAVAIL;
630 			goto bad;
631 		}
632 		src = sc->gif_psrc;
633 		switch (cmd) {
634 #ifdef INET
635 		case SIOCGIFPSRCADDR:
636 			dst = &ifr->ifr_addr;
637 			size = sizeof(ifr->ifr_addr);
638 			break;
639 #endif /* INET */
640 #ifdef INET6
641 		case SIOCGIFPSRCADDR_IN6:
642 			dst = (struct sockaddr *)
643 				&(((struct in6_ifreq *)data)->ifr_addr);
644 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
645 			break;
646 #endif /* INET6 */
647 		default:
648 			error = EADDRNOTAVAIL;
649 			goto bad;
650 		}
651 		if (src->sa_len > size)
652 			return EINVAL;
653 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
654 		break;
655 
656 	case SIOCGIFPDSTADDR:
657 #ifdef INET6
658 	case SIOCGIFPDSTADDR_IN6:
659 #endif /* INET6 */
660 		if (sc->gif_pdst == NULL) {
661 			error = EADDRNOTAVAIL;
662 			goto bad;
663 		}
664 		src = sc->gif_pdst;
665 		switch (cmd) {
666 #ifdef INET
667 		case SIOCGIFPDSTADDR:
668 			dst = &ifr->ifr_addr;
669 			size = sizeof(ifr->ifr_addr);
670 			break;
671 #endif /* INET */
672 #ifdef INET6
673 		case SIOCGIFPDSTADDR_IN6:
674 			dst = (struct sockaddr *)
675 				&(((struct in6_ifreq *)data)->ifr_addr);
676 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
677 			break;
678 #endif /* INET6 */
679 		default:
680 			error = EADDRNOTAVAIL;
681 			goto bad;
682 		}
683 		if (src->sa_len > size)
684 			return EINVAL;
685 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
686 		break;
687 
688 	case SIOCGLIFPHYADDR:
689 		if (sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
690 			error = EADDRNOTAVAIL;
691 			goto bad;
692 		}
693 
694 		/* copy src */
695 		src = sc->gif_psrc;
696 		dst = (struct sockaddr *)
697 			&(((struct if_laddrreq *)data)->addr);
698 		size = sizeof(((struct if_laddrreq *)data)->addr);
699 		if (src->sa_len > size)
700 			return EINVAL;
701 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
702 
703 		/* copy dst */
704 		src = sc->gif_pdst;
705 		dst = (struct sockaddr *)
706 			&(((struct if_laddrreq *)data)->dstaddr);
707 		size = sizeof(((struct if_laddrreq *)data)->dstaddr);
708 		if (src->sa_len > size)
709 			return EINVAL;
710 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
711 		break;
712 
713 	case SIOCSIFFLAGS:
714 		/* if_ioctl() takes care of it */
715 		break;
716 
717 	default:
718 		error = EINVAL;
719 		break;
720 	}
721  bad:
722 	return error;
723 }
724 
725 int
726 gif_set_tunnel(ifp, src, dst)
727 	struct ifnet *ifp;
728 	struct sockaddr *src;
729 	struct sockaddr *dst;
730 {
731 	struct gif_softc *sc = (struct gif_softc *)ifp;
732 	struct gif_softc *sc2;
733 	struct sockaddr *osrc, *odst, *sa;
734 	int s;
735 	int error = 0;
736 
737 	s = splnet();
738 
739 	LIST_FOREACH(sc2, &gif_softc_list, gif_list) {
740 		if (sc2 == sc)
741 			continue;
742 		if (!sc2->gif_pdst || !sc2->gif_psrc)
743 			continue;
744 		if (sc2->gif_pdst->sa_family != dst->sa_family ||
745 		    sc2->gif_pdst->sa_len != dst->sa_len ||
746 		    sc2->gif_psrc->sa_family != src->sa_family ||
747 		    sc2->gif_psrc->sa_len != src->sa_len)
748 			continue;
749 
750 		/*
751 		 * Disallow parallel tunnels unless instructed
752 		 * otherwise.
753 		 */
754 		if (!parallel_tunnels &&
755 		    bcmp(sc2->gif_pdst, dst, dst->sa_len) == 0 &&
756 		    bcmp(sc2->gif_psrc, src, src->sa_len) == 0) {
757 			error = EADDRNOTAVAIL;
758 			goto bad;
759 		}
760 
761 		/* XXX both end must be valid? (I mean, not 0.0.0.0) */
762 	}
763 
764 	/* XXX we can detach from both, but be polite just in case */
765 	if (sc->gif_psrc)
766 		switch (sc->gif_psrc->sa_family) {
767 #ifdef INET
768 		case AF_INET:
769 			(void)in_gif_detach(sc);
770 			break;
771 #endif
772 #ifdef INET6
773 		case AF_INET6:
774 			(void)in6_gif_detach(sc);
775 			break;
776 #endif
777 		}
778 
779 	osrc = sc->gif_psrc;
780 	sa = (struct sockaddr *)malloc(src->sa_len, M_IFADDR, M_WAITOK);
781 	bcopy((caddr_t)src, (caddr_t)sa, src->sa_len);
782 	sc->gif_psrc = sa;
783 
784 	odst = sc->gif_pdst;
785 	sa = (struct sockaddr *)malloc(dst->sa_len, M_IFADDR, M_WAITOK);
786 	bcopy((caddr_t)dst, (caddr_t)sa, dst->sa_len);
787 	sc->gif_pdst = sa;
788 
789 	switch (sc->gif_psrc->sa_family) {
790 #ifdef INET
791 	case AF_INET:
792 		error = in_gif_attach(sc);
793 		break;
794 #endif
795 #ifdef INET6
796 	case AF_INET6:
797 		error = in6_gif_attach(sc);
798 		break;
799 #endif
800 	}
801 	if (error) {
802 		/* rollback */
803 		free((caddr_t)sc->gif_psrc, M_IFADDR);
804 		free((caddr_t)sc->gif_pdst, M_IFADDR);
805 		sc->gif_psrc = osrc;
806 		sc->gif_pdst = odst;
807 		goto bad;
808 	}
809 
810 	if (osrc)
811 		free((caddr_t)osrc, M_IFADDR);
812 	if (odst)
813 		free((caddr_t)odst, M_IFADDR);
814 
815 	if (sc->gif_psrc && sc->gif_pdst)
816 		ifp->if_flags |= IFF_RUNNING;
817 	else
818 		ifp->if_flags &= ~IFF_RUNNING;
819 	splx(s);
820 
821 	return 0;
822 
823  bad:
824 	if (sc->gif_psrc && sc->gif_pdst)
825 		ifp->if_flags |= IFF_RUNNING;
826 	else
827 		ifp->if_flags &= ~IFF_RUNNING;
828 	splx(s);
829 
830 	return error;
831 }
832 
833 void
834 gif_delete_tunnel(ifp)
835 	struct ifnet *ifp;
836 {
837 	struct gif_softc *sc = (struct gif_softc *)ifp;
838 	int s;
839 
840 	s = splnet();
841 
842 	if (sc->gif_psrc) {
843 		free((caddr_t)sc->gif_psrc, M_IFADDR);
844 		sc->gif_psrc = NULL;
845 	}
846 	if (sc->gif_pdst) {
847 		free((caddr_t)sc->gif_pdst, M_IFADDR);
848 		sc->gif_pdst = NULL;
849 	}
850 	/* it is safe to detach from both */
851 #ifdef INET
852 	(void)in_gif_detach(sc);
853 #endif
854 #ifdef INET6
855 	(void)in6_gif_detach(sc);
856 #endif
857 
858 	if (sc->gif_psrc && sc->gif_pdst)
859 		ifp->if_flags |= IFF_RUNNING;
860 	else
861 		ifp->if_flags &= ~IFF_RUNNING;
862 	splx(s);
863 }
864