xref: /freebsd/sys/net/if_gif.c (revision 7773002178c8dbc52b44e4d705f07706409af8e4)
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 	if_initname(&sc->gif_if, ifc->ifc_name, unit);
145 
146 	gifattach0(sc);
147 
148 	LIST_INSERT_HEAD(&gif_softc_list, sc, gif_list);
149 	return (0);
150 }
151 
152 void
153 gifattach0(sc)
154 	struct gif_softc *sc;
155 {
156 
157 	sc->encap_cookie4 = sc->encap_cookie6 = NULL;
158 
159 	sc->gif_if.if_addrlen = 0;
160 	sc->gif_if.if_mtu    = GIF_MTU;
161 	sc->gif_if.if_flags  = IFF_POINTOPOINT | IFF_MULTICAST;
162 #if 0
163 	/* turn off ingress filter */
164 	sc->gif_if.if_flags  |= IFF_LINK2;
165 #endif
166 	sc->gif_if.if_ioctl  = gif_ioctl;
167 	sc->gif_if.if_output = gif_output;
168 	sc->gif_if.if_type   = IFT_GIF;
169 	sc->gif_if.if_snd.ifq_maxlen = IFQ_MAXLEN;
170 	if_attach(&sc->gif_if);
171 	bpfattach(&sc->gif_if, DLT_NULL, sizeof(u_int));
172 	if (ng_gif_attach_p != NULL)
173 		(*ng_gif_attach_p)(&sc->gif_if);
174 }
175 
176 void
177 gif_clone_destroy(ifp)
178 	struct ifnet *ifp;
179 {
180 	int err;
181 	struct gif_softc *sc = ifp->if_softc;
182 
183 	gif_delete_tunnel(&sc->gif_if);
184 	LIST_REMOVE(sc, gif_list);
185 #ifdef INET6
186 	if (sc->encap_cookie6 != NULL) {
187 		err = encap_detach(sc->encap_cookie6);
188 		KASSERT(err == 0, ("Unexpected error detaching encap_cookie6"));
189 	}
190 #endif
191 #ifdef INET
192 	if (sc->encap_cookie4 != NULL) {
193 		err = encap_detach(sc->encap_cookie4);
194 		KASSERT(err == 0, ("Unexpected error detaching encap_cookie4"));
195 	}
196 #endif
197 
198 	if (ng_gif_detach_p != NULL)
199 		(*ng_gif_detach_p)(ifp);
200 	bpfdetach(ifp);
201 	if_detach(ifp);
202 
203 	free(sc, M_GIF);
204 }
205 
206 static int
207 gifmodevent(mod, type, data)
208 	module_t mod;
209 	int type;
210 	void *data;
211 {
212 
213 	switch (type) {
214 	case MOD_LOAD:
215 		LIST_INIT(&gif_softc_list);
216 		if_clone_attach(&gif_cloner);
217 
218 #ifdef INET6
219 		ip6_gif_hlim = GIF_HLIM;
220 #endif
221 
222 		break;
223 	case MOD_UNLOAD:
224 		if_clone_detach(&gif_cloner);
225 
226 		while (!LIST_EMPTY(&gif_softc_list))
227 			gif_clone_destroy(&LIST_FIRST(&gif_softc_list)->gif_if);
228 
229 #ifdef INET6
230 		ip6_gif_hlim = 0;
231 #endif
232 		break;
233 	}
234 	return 0;
235 }
236 
237 static moduledata_t gif_mod = {
238 	"if_gif",
239 	gifmodevent,
240 	0
241 };
242 
243 DECLARE_MODULE(if_gif, gif_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
244 MODULE_VERSION(if_gif, 1);
245 
246 int
247 gif_encapcheck(m, off, proto, arg)
248 	const struct mbuf *m;
249 	int off;
250 	int proto;
251 	void *arg;
252 {
253 	struct ip ip;
254 	struct gif_softc *sc;
255 
256 	sc = (struct gif_softc *)arg;
257 	if (sc == NULL)
258 		return 0;
259 
260 	if ((sc->gif_if.if_flags & IFF_UP) == 0)
261 		return 0;
262 
263 	/* no physical address */
264 	if (!sc->gif_psrc || !sc->gif_pdst)
265 		return 0;
266 
267 	switch (proto) {
268 #ifdef INET
269 	case IPPROTO_IPV4:
270 		break;
271 #endif
272 #ifdef INET6
273 	case IPPROTO_IPV6:
274 		break;
275 #endif
276 	default:
277 		return 0;
278 	}
279 
280 	/* Bail on short packets */
281 	if (m->m_pkthdr.len < sizeof(ip))
282 		return 0;
283 
284 	m_copydata(m, 0, sizeof(ip), (caddr_t)&ip);
285 
286 	switch (ip.ip_v) {
287 #ifdef INET
288 	case 4:
289 		if (sc->gif_psrc->sa_family != AF_INET ||
290 		    sc->gif_pdst->sa_family != AF_INET)
291 			return 0;
292 		return gif_encapcheck4(m, off, proto, arg);
293 #endif
294 #ifdef INET6
295 	case 6:
296 		if (m->m_pkthdr.len < sizeof(struct ip6_hdr))
297 			return 0;
298 		if (sc->gif_psrc->sa_family != AF_INET6 ||
299 		    sc->gif_pdst->sa_family != AF_INET6)
300 			return 0;
301 		return gif_encapcheck6(m, off, proto, arg);
302 #endif
303 	default:
304 		return 0;
305 	}
306 }
307 
308 int
309 gif_output(ifp, m, dst, rt)
310 	struct ifnet *ifp;
311 	struct mbuf *m;
312 	struct sockaddr *dst;
313 	struct rtentry *rt;	/* added in net2 */
314 {
315 	struct gif_softc *sc = (struct gif_softc*)ifp;
316 	int error = 0;
317 	static int called = 0;	/* XXX: MUTEX */
318 
319 #ifdef MAC
320 	error = mac_check_ifnet_transmit(ifp, m);
321 	if (error) {
322 		m_freem(m);
323 		goto end;
324 	}
325 #endif
326 
327 	/*
328 	 * gif may cause infinite recursion calls when misconfigured.
329 	 * We'll prevent this by introducing upper limit.
330 	 * XXX: this mechanism may introduce another problem about
331 	 *      mutual exclusion of the variable CALLED, especially if we
332 	 *      use kernel thread.
333 	 */
334 	if (++called > max_gif_nesting) {
335 		log(LOG_NOTICE,
336 		    "gif_output: recursively called too many times(%d)\n",
337 		    called);
338 		m_freem(m);
339 		error = EIO;	/* is there better errno? */
340 		goto end;
341 	}
342 
343 	m->m_flags &= ~(M_BCAST|M_MCAST);
344 	if (!(ifp->if_flags & IFF_UP) ||
345 	    sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
346 		m_freem(m);
347 		error = ENETDOWN;
348 		goto end;
349 	}
350 
351 	if (ifp->if_bpf) {
352 		/*
353 		 * We need to prepend the address family as
354 		 * a four byte field.  Cons up a dummy header
355 		 * to pacify bpf.  This is safe because bpf
356 		 * will only read from the mbuf (i.e., it won't
357 		 * try to free it or keep a pointer a to it).
358 		 */
359 		struct mbuf m0;
360 		u_int32_t af = dst->sa_family;
361 
362 		m0.m_next = m;
363 		m0.m_len = 4;
364 		m0.m_data = (char *)&af;
365 
366 		BPF_MTAP(ifp, &m0);
367 	}
368 	ifp->if_opackets++;
369 	ifp->if_obytes += m->m_pkthdr.len;
370 
371 	/* inner AF-specific encapsulation */
372 
373 	/* XXX should we check if our outer source is legal? */
374 
375 	/* dispatch to output logic based on outer AF */
376 	switch (sc->gif_psrc->sa_family) {
377 #ifdef INET
378 	case AF_INET:
379 		error = in_gif_output(ifp, dst->sa_family, m);
380 		break;
381 #endif
382 #ifdef INET6
383 	case AF_INET6:
384 		error = in6_gif_output(ifp, dst->sa_family, m);
385 		break;
386 #endif
387 	default:
388 		m_freem(m);
389 		error = ENETDOWN;
390 		goto end;
391 	}
392 
393   end:
394 	called = 0;		/* reset recursion counter */
395 	if (error)
396 		ifp->if_oerrors++;
397 	return error;
398 }
399 
400 void
401 gif_input(m, af, ifp)
402 	struct mbuf *m;
403 	int af;
404 	struct ifnet *ifp;
405 {
406 	int isr;
407 
408 	if (ifp == NULL) {
409 		/* just in case */
410 		m_freem(m);
411 		return;
412 	}
413 
414 	m->m_pkthdr.rcvif = ifp;
415 
416 #ifdef MAC
417 	mac_create_mbuf_from_ifnet(ifp, m);
418 #endif
419 
420 	if (ifp->if_bpf) {
421 		/*
422 		 * We need to prepend the address family as
423 		 * a four byte field.  Cons up a dummy header
424 		 * to pacify bpf.  This is safe because bpf
425 		 * will only read from the mbuf (i.e., it won't
426 		 * try to free it or keep a pointer a to it).
427 		 */
428 		struct mbuf m0;
429 		u_int32_t af1 = af;
430 
431 		m0.m_next = m;
432 		m0.m_len = 4;
433 		m0.m_data = (char *)&af1;
434 
435 		BPF_MTAP(ifp, &m0);
436 	}
437 
438 	if (ng_gif_input_p != NULL) {
439 		(*ng_gif_input_p)(ifp, &m, af);
440 		if (m == NULL)
441 			return;
442 	}
443 
444 	/*
445 	 * Put the packet to the network layer input queue according to the
446 	 * specified address family.
447 	 * Note: older versions of gif_input directly called network layer
448 	 * input functions, e.g. ip6_input, here.  We changed the policy to
449 	 * prevent too many recursive calls of such input functions, which
450 	 * might cause kernel panic.  But the change may introduce another
451 	 * problem; if the input queue is full, packets are discarded.
452 	 * The kernel stack overflow really happened, and we believed
453 	 * queue-full rarely occurs, so we changed the policy.
454 	 */
455 	switch (af) {
456 #ifdef INET
457 	case AF_INET:
458 		isr = NETISR_IP;
459 		break;
460 #endif
461 #ifdef INET6
462 	case AF_INET6:
463 		isr = NETISR_IPV6;
464 		break;
465 #endif
466 	default:
467 		if (ng_gif_input_orphan_p != NULL)
468 			(*ng_gif_input_orphan_p)(ifp, m, af);
469 		else
470 			m_freem(m);
471 		return;
472 	}
473 
474 	ifp->if_ipackets++;
475 	ifp->if_ibytes += m->m_pkthdr.len;
476 	netisr_dispatch(isr, m);
477 }
478 
479 /* XXX how should we handle IPv6 scope on SIOC[GS]IFPHYADDR? */
480 int
481 gif_ioctl(ifp, cmd, data)
482 	struct ifnet *ifp;
483 	u_long cmd;
484 	caddr_t data;
485 {
486 	struct gif_softc *sc  = (struct gif_softc*)ifp;
487 	struct ifreq     *ifr = (struct ifreq*)data;
488 	int error = 0, size;
489 	struct sockaddr *dst, *src;
490 #ifdef	SIOCSIFMTU /* xxx */
491 	u_long mtu;
492 #endif
493 
494 	switch (cmd) {
495 	case SIOCSIFADDR:
496 		ifp->if_flags |= IFF_UP;
497 		break;
498 
499 	case SIOCSIFDSTADDR:
500 		break;
501 
502 	case SIOCADDMULTI:
503 	case SIOCDELMULTI:
504 		break;
505 
506 #ifdef	SIOCSIFMTU /* xxx */
507 	case SIOCGIFMTU:
508 		break;
509 
510 	case SIOCSIFMTU:
511 		mtu = ifr->ifr_mtu;
512 		if (mtu < GIF_MTU_MIN || mtu > GIF_MTU_MAX)
513 			return (EINVAL);
514 		ifp->if_mtu = mtu;
515 		break;
516 #endif /* SIOCSIFMTU */
517 
518 #ifdef INET
519 	case SIOCSIFPHYADDR:
520 #endif
521 #ifdef INET6
522 	case SIOCSIFPHYADDR_IN6:
523 #endif /* INET6 */
524 	case SIOCSLIFPHYADDR:
525 		switch (cmd) {
526 #ifdef INET
527 		case SIOCSIFPHYADDR:
528 			src = (struct sockaddr *)
529 				&(((struct in_aliasreq *)data)->ifra_addr);
530 			dst = (struct sockaddr *)
531 				&(((struct in_aliasreq *)data)->ifra_dstaddr);
532 			break;
533 #endif
534 #ifdef INET6
535 		case SIOCSIFPHYADDR_IN6:
536 			src = (struct sockaddr *)
537 				&(((struct in6_aliasreq *)data)->ifra_addr);
538 			dst = (struct sockaddr *)
539 				&(((struct in6_aliasreq *)data)->ifra_dstaddr);
540 			break;
541 #endif
542 		case SIOCSLIFPHYADDR:
543 			src = (struct sockaddr *)
544 				&(((struct if_laddrreq *)data)->addr);
545 			dst = (struct sockaddr *)
546 				&(((struct if_laddrreq *)data)->dstaddr);
547 			break;
548 		default:
549 			return EINVAL;
550 		}
551 
552 		/* sa_family must be equal */
553 		if (src->sa_family != dst->sa_family)
554 			return EINVAL;
555 
556 		/* validate sa_len */
557 		switch (src->sa_family) {
558 #ifdef INET
559 		case AF_INET:
560 			if (src->sa_len != sizeof(struct sockaddr_in))
561 				return EINVAL;
562 			break;
563 #endif
564 #ifdef INET6
565 		case AF_INET6:
566 			if (src->sa_len != sizeof(struct sockaddr_in6))
567 				return EINVAL;
568 			break;
569 #endif
570 		default:
571 			return EAFNOSUPPORT;
572 		}
573 		switch (dst->sa_family) {
574 #ifdef INET
575 		case AF_INET:
576 			if (dst->sa_len != sizeof(struct sockaddr_in))
577 				return EINVAL;
578 			break;
579 #endif
580 #ifdef INET6
581 		case AF_INET6:
582 			if (dst->sa_len != sizeof(struct sockaddr_in6))
583 				return EINVAL;
584 			break;
585 #endif
586 		default:
587 			return EAFNOSUPPORT;
588 		}
589 
590 		/* check sa_family looks sane for the cmd */
591 		switch (cmd) {
592 		case SIOCSIFPHYADDR:
593 			if (src->sa_family == AF_INET)
594 				break;
595 			return EAFNOSUPPORT;
596 #ifdef INET6
597 		case SIOCSIFPHYADDR_IN6:
598 			if (src->sa_family == AF_INET6)
599 				break;
600 			return EAFNOSUPPORT;
601 #endif /* INET6 */
602 		case SIOCSLIFPHYADDR:
603 			/* checks done in the above */
604 			break;
605 		}
606 
607 		error = gif_set_tunnel(&sc->gif_if, src, dst);
608 		break;
609 
610 #ifdef SIOCDIFPHYADDR
611 	case SIOCDIFPHYADDR:
612 		gif_delete_tunnel(&sc->gif_if);
613 		break;
614 #endif
615 
616 	case SIOCGIFPSRCADDR:
617 #ifdef INET6
618 	case SIOCGIFPSRCADDR_IN6:
619 #endif /* INET6 */
620 		if (sc->gif_psrc == NULL) {
621 			error = EADDRNOTAVAIL;
622 			goto bad;
623 		}
624 		src = sc->gif_psrc;
625 		switch (cmd) {
626 #ifdef INET
627 		case SIOCGIFPSRCADDR:
628 			dst = &ifr->ifr_addr;
629 			size = sizeof(ifr->ifr_addr);
630 			break;
631 #endif /* INET */
632 #ifdef INET6
633 		case SIOCGIFPSRCADDR_IN6:
634 			dst = (struct sockaddr *)
635 				&(((struct in6_ifreq *)data)->ifr_addr);
636 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
637 			break;
638 #endif /* INET6 */
639 		default:
640 			error = EADDRNOTAVAIL;
641 			goto bad;
642 		}
643 		if (src->sa_len > size)
644 			return EINVAL;
645 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
646 		break;
647 
648 	case SIOCGIFPDSTADDR:
649 #ifdef INET6
650 	case SIOCGIFPDSTADDR_IN6:
651 #endif /* INET6 */
652 		if (sc->gif_pdst == NULL) {
653 			error = EADDRNOTAVAIL;
654 			goto bad;
655 		}
656 		src = sc->gif_pdst;
657 		switch (cmd) {
658 #ifdef INET
659 		case SIOCGIFPDSTADDR:
660 			dst = &ifr->ifr_addr;
661 			size = sizeof(ifr->ifr_addr);
662 			break;
663 #endif /* INET */
664 #ifdef INET6
665 		case SIOCGIFPDSTADDR_IN6:
666 			dst = (struct sockaddr *)
667 				&(((struct in6_ifreq *)data)->ifr_addr);
668 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
669 			break;
670 #endif /* INET6 */
671 		default:
672 			error = EADDRNOTAVAIL;
673 			goto bad;
674 		}
675 		if (src->sa_len > size)
676 			return EINVAL;
677 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
678 		break;
679 
680 	case SIOCGLIFPHYADDR:
681 		if (sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
682 			error = EADDRNOTAVAIL;
683 			goto bad;
684 		}
685 
686 		/* copy src */
687 		src = sc->gif_psrc;
688 		dst = (struct sockaddr *)
689 			&(((struct if_laddrreq *)data)->addr);
690 		size = sizeof(((struct if_laddrreq *)data)->addr);
691 		if (src->sa_len > size)
692 			return EINVAL;
693 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
694 
695 		/* copy dst */
696 		src = sc->gif_pdst;
697 		dst = (struct sockaddr *)
698 			&(((struct if_laddrreq *)data)->dstaddr);
699 		size = sizeof(((struct if_laddrreq *)data)->dstaddr);
700 		if (src->sa_len > size)
701 			return EINVAL;
702 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
703 		break;
704 
705 	case SIOCSIFFLAGS:
706 		/* if_ioctl() takes care of it */
707 		break;
708 
709 	default:
710 		error = EINVAL;
711 		break;
712 	}
713  bad:
714 	return error;
715 }
716 
717 int
718 gif_set_tunnel(ifp, src, dst)
719 	struct ifnet *ifp;
720 	struct sockaddr *src;
721 	struct sockaddr *dst;
722 {
723 	struct gif_softc *sc = (struct gif_softc *)ifp;
724 	struct gif_softc *sc2;
725 	struct sockaddr *osrc, *odst, *sa;
726 	int s;
727 	int error = 0;
728 
729 	s = splnet();
730 
731 	LIST_FOREACH(sc2, &gif_softc_list, gif_list) {
732 		if (sc2 == sc)
733 			continue;
734 		if (!sc2->gif_pdst || !sc2->gif_psrc)
735 			continue;
736 		if (sc2->gif_pdst->sa_family != dst->sa_family ||
737 		    sc2->gif_pdst->sa_len != dst->sa_len ||
738 		    sc2->gif_psrc->sa_family != src->sa_family ||
739 		    sc2->gif_psrc->sa_len != src->sa_len)
740 			continue;
741 
742 		/*
743 		 * Disallow parallel tunnels unless instructed
744 		 * otherwise.
745 		 */
746 		if (!parallel_tunnels &&
747 		    bcmp(sc2->gif_pdst, dst, dst->sa_len) == 0 &&
748 		    bcmp(sc2->gif_psrc, src, src->sa_len) == 0) {
749 			error = EADDRNOTAVAIL;
750 			goto bad;
751 		}
752 
753 		/* XXX both end must be valid? (I mean, not 0.0.0.0) */
754 	}
755 
756 	/* XXX we can detach from both, but be polite just in case */
757 	if (sc->gif_psrc)
758 		switch (sc->gif_psrc->sa_family) {
759 #ifdef INET
760 		case AF_INET:
761 			(void)in_gif_detach(sc);
762 			break;
763 #endif
764 #ifdef INET6
765 		case AF_INET6:
766 			(void)in6_gif_detach(sc);
767 			break;
768 #endif
769 		}
770 
771 	osrc = sc->gif_psrc;
772 	sa = (struct sockaddr *)malloc(src->sa_len, M_IFADDR, M_WAITOK);
773 	bcopy((caddr_t)src, (caddr_t)sa, src->sa_len);
774 	sc->gif_psrc = sa;
775 
776 	odst = sc->gif_pdst;
777 	sa = (struct sockaddr *)malloc(dst->sa_len, M_IFADDR, M_WAITOK);
778 	bcopy((caddr_t)dst, (caddr_t)sa, dst->sa_len);
779 	sc->gif_pdst = sa;
780 
781 	switch (sc->gif_psrc->sa_family) {
782 #ifdef INET
783 	case AF_INET:
784 		error = in_gif_attach(sc);
785 		break;
786 #endif
787 #ifdef INET6
788 	case AF_INET6:
789 		error = in6_gif_attach(sc);
790 		break;
791 #endif
792 	}
793 	if (error) {
794 		/* rollback */
795 		free((caddr_t)sc->gif_psrc, M_IFADDR);
796 		free((caddr_t)sc->gif_pdst, M_IFADDR);
797 		sc->gif_psrc = osrc;
798 		sc->gif_pdst = odst;
799 		goto bad;
800 	}
801 
802 	if (osrc)
803 		free((caddr_t)osrc, M_IFADDR);
804 	if (odst)
805 		free((caddr_t)odst, M_IFADDR);
806 
807 	if (sc->gif_psrc && sc->gif_pdst)
808 		ifp->if_flags |= IFF_RUNNING;
809 	else
810 		ifp->if_flags &= ~IFF_RUNNING;
811 	splx(s);
812 
813 	return 0;
814 
815  bad:
816 	if (sc->gif_psrc && sc->gif_pdst)
817 		ifp->if_flags |= IFF_RUNNING;
818 	else
819 		ifp->if_flags &= ~IFF_RUNNING;
820 	splx(s);
821 
822 	return error;
823 }
824 
825 void
826 gif_delete_tunnel(ifp)
827 	struct ifnet *ifp;
828 {
829 	struct gif_softc *sc = (struct gif_softc *)ifp;
830 	int s;
831 
832 	s = splnet();
833 
834 	if (sc->gif_psrc) {
835 		free((caddr_t)sc->gif_psrc, M_IFADDR);
836 		sc->gif_psrc = NULL;
837 	}
838 	if (sc->gif_pdst) {
839 		free((caddr_t)sc->gif_pdst, M_IFADDR);
840 		sc->gif_pdst = NULL;
841 	}
842 	/* it is safe to detach from both */
843 #ifdef INET
844 	(void)in_gif_detach(sc);
845 #endif
846 #ifdef INET6
847 	(void)in6_gif_detach(sc);
848 #endif
849 
850 	if (sc->gif_psrc && sc->gif_pdst)
851 		ifp->if_flags |= IFF_RUNNING;
852 	else
853 		ifp->if_flags &= ~IFF_RUNNING;
854 	splx(s);
855 }
856