xref: /dragonfly/sys/net/gif/if_gif.c (revision 33311965) 
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 1.21 2008/05/14 11:59:23 sephe 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/ifq_var.h>
58 #include <net/netisr.h>
59 #include <net/route.h>
60 #include <net/bpf.h>
61 #include <net/if_clone.h>
62 
63 #include <netinet/in.h>
64 #include <netinet/in_systm.h>
65 #include <netinet/ip.h>
66 #ifdef	INET
67 #include <netinet/in_var.h>
68 #include <netinet/in_gif.h>
69 #include <netinet/ip_var.h>
70 #endif	/* INET */
71 
72 #ifdef INET6
73 #ifndef INET
74 #include <netinet/in.h>
75 #endif
76 #include <netinet6/in6_var.h>
77 #include <netinet/ip6.h>
78 #include <netinet6/ip6_var.h>
79 #include <netinet6/in6_gif.h>
80 #include <netinet6/ip6protosw.h>
81 #endif /* INET6 */
82 
83 #include <netinet/ip_encap.h>
84 #include "if_gif.h"
85 
86 #include <net/net_osdep.h>
87 
88 #define GIFNAME		"gif"
89 
90 static MALLOC_DEFINE(M_GIF, "gif", "Generic Tunnel Interface");
91 LIST_HEAD(, gif_softc) gif_softc_list;
92 
93 int	gif_clone_create (struct if_clone *, int, caddr_t);
94 int	gif_clone_destroy (struct ifnet *);
95 
96 struct if_clone gif_cloner = IF_CLONE_INITIALIZER("gif", gif_clone_create,
97     gif_clone_destroy, 0, IF_MAXUNIT);
98 
99 static int gifmodevent (module_t, int, void *);
100 static void gif_clear_cache(struct gif_softc *sc);
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(struct if_clone *ifc, int unit, caddr_t params)
135 {
136 	struct gif_softc *sc;
137 
138 	sc = kmalloc (sizeof(struct gif_softc), M_GIF, M_WAITOK | M_ZERO);
139 
140 	sc->gif_if.if_softc = sc;
141 	if_initname(&(sc->gif_if), GIFNAME, unit);
142 
143 	gifattach0(sc);
144 
145 	LIST_INSERT_HEAD(&gif_softc_list, sc, gif_list);
146 	return (0);
147 }
148 
149 void
150 gifattach0(struct gif_softc *sc)
151 {
152 
153 	sc->encap_cookie4 = sc->encap_cookie6 = NULL;
154 
155 	sc->gif_if.if_addrlen = 0;
156 	sc->gif_if.if_mtu    = GIF_MTU;
157 	sc->gif_if.if_flags  = IFF_POINTOPOINT | IFF_MULTICAST;
158 #if 0
159 	/* turn off ingress filter */
160 	sc->gif_if.if_flags  |= IFF_LINK2;
161 #endif
162 	sc->gif_if.if_ioctl  = gif_ioctl;
163 	sc->gif_if.if_output = gif_output;
164 	sc->gif_if.if_type   = IFT_GIF;
165 	ifq_set_maxlen(&sc->gif_if.if_snd, IFQ_MAXLEN);
166 	if_attach(&sc->gif_if, NULL);
167 	bpfattach(&sc->gif_if, DLT_NULL, sizeof(u_int));
168 }
169 
170 int
171 gif_clone_destroy(struct ifnet *ifp)
172 {
173 	struct gif_softc *sc = ifp->if_softc;
174 	int err;
175 
176 	gif_delete_tunnel(&sc->gif_if);
177 	LIST_REMOVE(sc, gif_list);
178 #ifdef INET6
179 	if (sc->encap_cookie6 != NULL) {
180 		err = encap_detach(sc->encap_cookie6);
181 		KASSERT(err == 0, ("Unexpected error detaching encap_cookie6"));
182 	}
183 #endif
184 #ifdef INET
185 	if (sc->encap_cookie4 != NULL) {
186 		err = encap_detach(sc->encap_cookie4);
187 		KASSERT(err == 0, ("Unexpected error detaching encap_cookie4"));
188 	}
189 #endif
190 	gif_clear_cache(sc);
191 
192 	bpfdetach(ifp);
193 	if_detach(ifp);
194 
195 	kfree(sc, M_GIF);
196 
197 	return 0;
198 }
199 
200 static void
201 gif_clear_cache(struct gif_softc *sc)
202 {
203 	int n;
204 
205 	for (n = 0; n < ncpus; ++n) {
206 		if (sc->gif_ro[n].ro_rt) {
207 			RTFREE(sc->gif_ro[n].ro_rt);
208 			sc->gif_ro[n].ro_rt = NULL;
209 		}
210 #ifdef INET6
211 		if (sc->gif_ro6[n].ro_rt) {
212 			RTFREE(sc->gif_ro6[n].ro_rt);
213 			sc->gif_ro6[n].ro_rt = NULL;
214 		}
215 #endif
216 	}
217 }
218 
219 static int
220 gifmodevent(module_t mod, int type, void *data)
221 {
222 
223 	switch (type) {
224 	case MOD_LOAD:
225 		LIST_INIT(&gif_softc_list);
226 		if_clone_attach(&gif_cloner);
227 
228 #ifdef INET6
229 		ip6_gif_hlim = GIF_HLIM;
230 #endif
231 
232 		break;
233 	case MOD_UNLOAD:
234 		if_clone_detach(&gif_cloner);
235 
236 		while (!LIST_EMPTY(&gif_softc_list))
237 			gif_clone_destroy(&LIST_FIRST(&gif_softc_list)->gif_if);
238 
239 #ifdef INET6
240 		ip6_gif_hlim = 0;
241 #endif
242 		break;
243 	}
244 	return 0;
245 }
246 
247 static moduledata_t gif_mod = {
248 	"if_gif",
249 	gifmodevent,
250 	0
251 };
252 
253 DECLARE_MODULE(if_gif, gif_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
254 
255 int
256 gif_encapcheck(const struct mbuf *m, int off, int proto, void *arg)
257 {
258 	struct ip ip;
259 	struct gif_softc *sc;
260 
261 	sc = (struct gif_softc *)arg;
262 	if (sc == NULL)
263 		return 0;
264 
265 	if ((sc->gif_if.if_flags & IFF_UP) == 0)
266 		return 0;
267 
268 	/* no physical address */
269 	if (!sc->gif_psrc || !sc->gif_pdst)
270 		return 0;
271 
272 	switch (proto) {
273 #ifdef INET
274 	case IPPROTO_IPV4:
275 		break;
276 #endif
277 #ifdef INET6
278 	case IPPROTO_IPV6:
279 		break;
280 #endif
281 	default:
282 		return 0;
283 	}
284 
285 	/* Bail on short packets */
286 	if (m->m_pkthdr.len < sizeof(ip))
287 		return 0;
288 
289 	m_copydata(m, 0, sizeof(ip), (caddr_t)&ip);
290 
291 	switch (ip.ip_v) {
292 #ifdef INET
293 	case 4:
294 		if (sc->gif_psrc->sa_family != AF_INET ||
295 		    sc->gif_pdst->sa_family != AF_INET)
296 			return 0;
297 		return gif_encapcheck4(m, off, proto, arg);
298 #endif
299 #ifdef INET6
300 	case 6:
301 		if (m->m_pkthdr.len < sizeof(struct ip6_hdr))
302 			return 0;
303 		if (sc->gif_psrc->sa_family != AF_INET6 ||
304 		    sc->gif_pdst->sa_family != AF_INET6)
305 			return 0;
306 		return gif_encapcheck6(m, off, proto, arg);
307 #endif
308 	default:
309 		return 0;
310 	}
311 }
312 
313 /*
314  * Parameters:
315  *	rt:	added in net2
316  */
317 static int
318 gif_output_serialized(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
319 		      struct rtentry *rt)
320 {
321 	struct gif_softc *sc = (struct gif_softc*)ifp;
322 	int error = 0;
323 	static int called = 0;	/* XXX: MUTEX */
324 
325 	/*
326 	 * gif may cause infinite recursion calls when misconfigured.
327 	 * We'll prevent this by introducing upper limit.
328 	 * XXX: this mechanism may introduce another problem about
329 	 *      mutual exclusion of the variable CALLED, especially if we
330 	 *      use kernel thread.
331 	 */
332 	if (++called > max_gif_nesting) {
333 		log(LOG_NOTICE,
334 		    "gif_output: recursively called too many times(%d)\n",
335 		    called);
336 		m_freem(m);
337 		error = EIO;	/* is there better errno? */
338 		goto end;
339 	}
340 
341 	m->m_flags &= ~(M_BCAST|M_MCAST);
342 	if (!(ifp->if_flags & IFF_UP) ||
343 	    sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
344 		m_freem(m);
345 		error = ENETDOWN;
346 		goto end;
347 	}
348 
349 	if (ifp->if_bpf) {
350 		bpf_gettoken();
351 		if (ifp->if_bpf) {
352 			/*
353 			 * We need to prepend the address family as
354 			 * a four byte field.
355 			 */
356 			uint32_t af = dst->sa_family;
357 
358 			bpf_ptap(ifp->if_bpf, m, &af, sizeof(af));
359 		}
360 		bpf_reltoken();
361 	}
362 	IFNET_STAT_INC(ifp, opackets, 1);
363 	IFNET_STAT_INC(ifp, obytes, m->m_pkthdr.len);
364 
365 	/* inner AF-specific encapsulation */
366 
367 	/* XXX should we check if our outer source is legal? */
368 
369 	/* dispatch to output logic based on outer AF */
370 	switch (sc->gif_psrc->sa_family) {
371 #ifdef INET
372 	case AF_INET:
373 		error = in_gif_output(ifp, dst->sa_family, m);
374 		break;
375 #endif
376 #ifdef INET6
377 	case AF_INET6:
378 		error = in6_gif_output(ifp, dst->sa_family, m);
379 		break;
380 #endif
381 	default:
382 		m_freem(m);
383 		error = ENETDOWN;
384 		goto end;
385 	}
386 
387   end:
388 	called = 0;		/* reset recursion counter */
389 	if (error)
390 		IFNET_STAT_INC(ifp, oerrors, 1);
391 	return error;
392 }
393 
394 int
395 gif_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
396 	   struct rtentry *rt)
397 {
398 	struct ifaltq_subque *ifsq = ifq_get_subq_default(&ifp->if_snd);
399 	int error;
400 
401 	ifsq_serialize_hw(ifsq);
402 	error = gif_output_serialized(ifp, m, dst, rt);
403 	ifsq_deserialize_hw(ifsq);
404 	return error;
405 }
406 
407 void
408 gif_input(struct mbuf *m, int af, struct ifnet *ifp)
409 {
410 	int isr;
411 
412 	if (ifp == NULL) {
413 		/* just in case */
414 		m_freem(m);
415 		return;
416 	}
417 
418 	m->m_pkthdr.rcvif = ifp;
419 
420 	if (ifp->if_bpf) {
421 		bpf_gettoken();
422 		if (ifp->if_bpf) {
423 			/*
424 			 * We need to prepend the address family as
425 			 * a four byte field.
426 			 */
427 			uint32_t af1 = af;
428 
429 			bpf_ptap(ifp->if_bpf, m, &af1, sizeof(af1));
430 		}
431 		bpf_reltoken();
432 	}
433 
434 	/*
435 	 * Put the packet to the network layer input queue according to the
436 	 * specified address family.
437 	 * Note: older versions of gif_input directly called network layer
438 	 * input functions, e.g. ip6_input, here.  We changed the policy to
439 	 * prevent too many recursive calls of such input functions, which
440 	 * might cause kernel panic.  But the change may introduce another
441 	 * problem; if the input queue is full, packets are discarded.
442 	 * The kernel stack overflow really happened, and we believed
443 	 * queue-full rarely occurs, so we changed the policy.
444 	 */
445 	switch (af) {
446 #ifdef INET
447 	case AF_INET:
448 		isr = NETISR_IP;
449 		break;
450 #endif
451 #ifdef INET6
452 	case AF_INET6:
453 		isr = NETISR_IPV6;
454 		break;
455 #endif
456 	default:
457 		m_freem(m);
458 		return;
459 	}
460 
461 	IFNET_STAT_INC(ifp, ipackets, 1);
462 	IFNET_STAT_INC(ifp, ibytes, m->m_pkthdr.len);
463 	m->m_flags &= ~M_HASH;
464 	netisr_queue(isr, m);
465 
466 	return;
467 }
468 
469 /* XXX how should we handle IPv6 scope on SIOC[GS]IFPHYADDR? */
470 int
471 gif_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data, struct ucred *cr)
472 {
473 	struct gif_softc *sc  = (struct gif_softc*)ifp;
474 	struct ifreq     *ifr = (struct ifreq*)data;
475 	int error = 0, size;
476 	struct sockaddr *dst, *src;
477 #ifdef	SIOCSIFMTU /* xxx */
478 	u_long mtu;
479 #endif
480 
481 	switch (cmd) {
482 	case SIOCSIFADDR:
483 		ifp->if_flags |= IFF_UP;
484 		break;
485 
486 	case SIOCSIFDSTADDR:
487 		break;
488 
489 	case SIOCADDMULTI:
490 	case SIOCDELMULTI:
491 		break;
492 
493 #ifdef	SIOCSIFMTU /* xxx */
494 	case SIOCGIFMTU:
495 		break;
496 
497 	case SIOCSIFMTU:
498 		mtu = ifr->ifr_mtu;
499 		if (mtu < GIF_MTU_MIN || mtu > GIF_MTU_MAX)
500 			return (EINVAL);
501 		ifp->if_mtu = mtu;
502 		break;
503 #endif /* SIOCSIFMTU */
504 
505 #ifdef INET
506 	case SIOCSIFPHYADDR:
507 #endif
508 #ifdef INET6
509 	case SIOCSIFPHYADDR_IN6:
510 #endif /* INET6 */
511 	case SIOCSLIFPHYADDR:
512 		switch (cmd) {
513 #ifdef INET
514 		case SIOCSIFPHYADDR:
515 			src = (struct sockaddr *)
516 				&(((struct in_aliasreq *)data)->ifra_addr);
517 			dst = (struct sockaddr *)
518 				&(((struct in_aliasreq *)data)->ifra_dstaddr);
519 			break;
520 #endif
521 #ifdef INET6
522 		case SIOCSIFPHYADDR_IN6:
523 			src = (struct sockaddr *)
524 				&(((struct in6_aliasreq *)data)->ifra_addr);
525 			dst = (struct sockaddr *)
526 				&(((struct in6_aliasreq *)data)->ifra_dstaddr);
527 			break;
528 #endif
529 		case SIOCSLIFPHYADDR:
530 			src = (struct sockaddr *)
531 				&(((struct if_laddrreq *)data)->addr);
532 			dst = (struct sockaddr *)
533 				&(((struct if_laddrreq *)data)->dstaddr);
534 			break;
535 		default:
536 			return EINVAL;
537 		}
538 
539 		/* sa_family must be equal */
540 		if (src->sa_family != dst->sa_family)
541 			return EINVAL;
542 
543 		/* validate sa_len */
544 		switch (src->sa_family) {
545 #ifdef INET
546 		case AF_INET:
547 			if (src->sa_len != sizeof(struct sockaddr_in))
548 				return EINVAL;
549 			break;
550 #endif
551 #ifdef INET6
552 		case AF_INET6:
553 			if (src->sa_len != sizeof(struct sockaddr_in6))
554 				return EINVAL;
555 			break;
556 #endif
557 		default:
558 			return EAFNOSUPPORT;
559 		}
560 		switch (dst->sa_family) {
561 #ifdef INET
562 		case AF_INET:
563 			if (dst->sa_len != sizeof(struct sockaddr_in))
564 				return EINVAL;
565 			break;
566 #endif
567 #ifdef INET6
568 		case AF_INET6:
569 			if (dst->sa_len != sizeof(struct sockaddr_in6))
570 				return EINVAL;
571 			break;
572 #endif
573 		default:
574 			return EAFNOSUPPORT;
575 		}
576 
577 		/* check sa_family looks sane for the cmd */
578 		switch (cmd) {
579 		case SIOCSIFPHYADDR:
580 			if (src->sa_family == AF_INET)
581 				break;
582 			return EAFNOSUPPORT;
583 #ifdef INET6
584 		case SIOCSIFPHYADDR_IN6:
585 			if (src->sa_family == AF_INET6)
586 				break;
587 			return EAFNOSUPPORT;
588 #endif /* INET6 */
589 		case SIOCSLIFPHYADDR:
590 			/* checks done in the above */
591 			break;
592 		}
593 
594 		error = gif_set_tunnel(&sc->gif_if, src, dst);
595 		break;
596 
597 #ifdef SIOCDIFPHYADDR
598 	case SIOCDIFPHYADDR:
599 		gif_delete_tunnel(&sc->gif_if);
600 		break;
601 #endif
602 
603 	case SIOCGIFPSRCADDR:
604 #ifdef INET6
605 	case SIOCGIFPSRCADDR_IN6:
606 #endif /* INET6 */
607 		if (sc->gif_psrc == NULL) {
608 			error = EADDRNOTAVAIL;
609 			goto bad;
610 		}
611 		src = sc->gif_psrc;
612 		switch (cmd) {
613 #ifdef INET
614 		case SIOCGIFPSRCADDR:
615 			dst = &ifr->ifr_addr;
616 			size = sizeof(ifr->ifr_addr);
617 			break;
618 #endif /* INET */
619 #ifdef INET6
620 		case SIOCGIFPSRCADDR_IN6:
621 			dst = (struct sockaddr *)
622 				&(((struct in6_ifreq *)data)->ifr_addr);
623 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
624 			break;
625 #endif /* INET6 */
626 		default:
627 			error = EADDRNOTAVAIL;
628 			goto bad;
629 		}
630 		if (src->sa_len > size)
631 			return EINVAL;
632 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
633 		break;
634 
635 	case SIOCGIFPDSTADDR:
636 #ifdef INET6
637 	case SIOCGIFPDSTADDR_IN6:
638 #endif /* INET6 */
639 		if (sc->gif_pdst == NULL) {
640 			error = EADDRNOTAVAIL;
641 			goto bad;
642 		}
643 		src = sc->gif_pdst;
644 		switch (cmd) {
645 #ifdef INET
646 		case SIOCGIFPDSTADDR:
647 			dst = &ifr->ifr_addr;
648 			size = sizeof(ifr->ifr_addr);
649 			break;
650 #endif /* INET */
651 #ifdef INET6
652 		case SIOCGIFPDSTADDR_IN6:
653 			dst = (struct sockaddr *)
654 				&(((struct in6_ifreq *)data)->ifr_addr);
655 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
656 			break;
657 #endif /* INET6 */
658 		default:
659 			error = EADDRNOTAVAIL;
660 			goto bad;
661 		}
662 		if (src->sa_len > size)
663 			return EINVAL;
664 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
665 		break;
666 
667 	case SIOCGLIFPHYADDR:
668 		if (sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
669 			error = EADDRNOTAVAIL;
670 			goto bad;
671 		}
672 
673 		/* copy src */
674 		src = sc->gif_psrc;
675 		dst = (struct sockaddr *)
676 			&(((struct if_laddrreq *)data)->addr);
677 		size = sizeof(((struct if_laddrreq *)data)->addr);
678 		if (src->sa_len > size)
679 			return EINVAL;
680 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
681 
682 		/* copy dst */
683 		src = sc->gif_pdst;
684 		dst = (struct sockaddr *)
685 			&(((struct if_laddrreq *)data)->dstaddr);
686 		size = sizeof(((struct if_laddrreq *)data)->dstaddr);
687 		if (src->sa_len > size)
688 			return EINVAL;
689 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
690 		break;
691 
692 	case SIOCSIFFLAGS:
693 		/* if_ioctl() takes care of it */
694 		break;
695 
696 	default:
697 		error = EINVAL;
698 		break;
699 	}
700  bad:
701 	return error;
702 }
703 
704 int
705 gif_set_tunnel(struct ifnet *ifp, struct sockaddr *src, struct sockaddr *dst)
706 {
707 	struct gif_softc *sc = (struct gif_softc *)ifp;
708 	struct gif_softc *sc2;
709 	struct sockaddr *osrc, *odst, *sa;
710 	int error = 0;
711 
712 	crit_enter();
713 
714 	LIST_FOREACH(sc2, &gif_softc_list, gif_list) {
715 		if (sc2 == sc)
716 			continue;
717 		if (!sc2->gif_pdst || !sc2->gif_psrc)
718 			continue;
719 		if (sc2->gif_pdst->sa_family != dst->sa_family ||
720 		    sc2->gif_pdst->sa_len != dst->sa_len ||
721 		    sc2->gif_psrc->sa_family != src->sa_family ||
722 		    sc2->gif_psrc->sa_len != src->sa_len)
723 			continue;
724 
725 		/*
726 		 * Disallow parallel tunnels unless instructed
727 		 * otherwise.
728 		 */
729 		if (!parallel_tunnels &&
730 		    bcmp(sc2->gif_pdst, dst, dst->sa_len) == 0 &&
731 		    bcmp(sc2->gif_psrc, src, src->sa_len) == 0) {
732 			error = EADDRNOTAVAIL;
733 			goto bad;
734 		}
735 
736 		/* XXX both end must be valid? (I mean, not 0.0.0.0) */
737 	}
738 
739 	/* XXX we can detach from both, but be polite just in case */
740 	if (sc->gif_psrc) {
741 		switch (sc->gif_psrc->sa_family) {
742 #ifdef INET
743 		case AF_INET:
744 			in_gif_detach(sc);
745 			break;
746 #endif
747 #ifdef INET6
748 		case AF_INET6:
749 			in6_gif_detach(sc);
750 			break;
751 #endif
752 		}
753 		gif_clear_cache(sc);
754 	}
755 
756 	osrc = sc->gif_psrc;
757 	sa = (struct sockaddr *)kmalloc(src->sa_len, M_IFADDR, M_WAITOK);
758 	bcopy((caddr_t)src, (caddr_t)sa, src->sa_len);
759 	sc->gif_psrc = sa;
760 
761 	odst = sc->gif_pdst;
762 	sa = (struct sockaddr *)kmalloc(dst->sa_len, M_IFADDR, M_WAITOK);
763 	bcopy((caddr_t)dst, (caddr_t)sa, dst->sa_len);
764 	sc->gif_pdst = sa;
765 
766 	switch (sc->gif_psrc->sa_family) {
767 #ifdef INET
768 	case AF_INET:
769 		error = in_gif_attach(sc);
770 		break;
771 #endif
772 #ifdef INET6
773 	case AF_INET6:
774 		error = in6_gif_attach(sc);
775 		break;
776 #endif
777 	}
778 	if (error) {
779 		/* rollback */
780 		kfree((caddr_t)sc->gif_psrc, M_IFADDR);
781 		kfree((caddr_t)sc->gif_pdst, M_IFADDR);
782 		sc->gif_psrc = osrc;
783 		sc->gif_pdst = odst;
784 		goto bad;
785 	}
786 
787 	if (osrc)
788 		kfree((caddr_t)osrc, M_IFADDR);
789 	if (odst)
790 		kfree((caddr_t)odst, M_IFADDR);
791 
792 	if (sc->gif_psrc && sc->gif_pdst)
793 		ifp->if_flags |= IFF_RUNNING;
794 	else
795 		ifp->if_flags &= ~IFF_RUNNING;
796 	crit_exit();
797 
798 	return 0;
799 
800  bad:
801 	if (sc->gif_psrc && sc->gif_pdst)
802 		ifp->if_flags |= IFF_RUNNING;
803 	else
804 		ifp->if_flags &= ~IFF_RUNNING;
805 	crit_exit();
806 
807 	return error;
808 }
809 
810 void
811 gif_delete_tunnel(struct ifnet *ifp)
812 {
813 	struct gif_softc *sc = (struct gif_softc *)ifp;
814 
815 	crit_enter();
816 
817 	if (sc->gif_psrc) {
818 		kfree((caddr_t)sc->gif_psrc, M_IFADDR);
819 		sc->gif_psrc = NULL;
820 	}
821 	if (sc->gif_pdst) {
822 		kfree((caddr_t)sc->gif_pdst, M_IFADDR);
823 		sc->gif_pdst = NULL;
824 	}
825 	/* it is safe to detach from both */
826 #ifdef INET
827 	in_gif_detach(sc);
828 #endif
829 #ifdef INET6
830 	in6_gif_detach(sc);
831 #endif
832 	gif_clear_cache(sc);
833 
834 	if (sc->gif_psrc && sc->gif_pdst)
835 		ifp->if_flags |= IFF_RUNNING;
836 	else
837 		ifp->if_flags &= ~IFF_RUNNING;
838 	crit_exit();
839 }
840