xref: /freebsd/sys/net/if_gif.c (revision 822923447e454b30d310cb46903c9ddeca9f0a7a)
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/module.h>
44 #include <sys/socket.h>
45 #include <sys/sockio.h>
46 #include <sys/errno.h>
47 #include <sys/time.h>
48 #include <sys/sysctl.h>
49 #include <sys/syslog.h>
50 #include <sys/protosw.h>
51 #include <sys/conf.h>
52 #include <machine/cpu.h>
53 
54 #include <net/if.h>
55 #include <net/if_clone.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/scope6_var.h>
78 #include <netinet6/in6_gif.h>
79 #include <netinet6/ip6protosw.h>
80 #endif /* INET6 */
81 
82 #include <netinet/ip_encap.h>
83 #include <net/if_gif.h>
84 
85 #include <net/net_osdep.h>
86 
87 #define GIFNAME		"gif"
88 
89 /*
90  * gif_mtx protects the global gif_softc_list.
91  * XXX: Per-softc locking is still required.
92  */
93 static struct mtx gif_mtx;
94 static MALLOC_DEFINE(M_GIF, "gif", "Generic Tunnel Interface");
95 static LIST_HEAD(, gif_softc) gif_softc_list;
96 
97 void	(*ng_gif_input_p)(struct ifnet *ifp, struct mbuf **mp, int af);
98 void	(*ng_gif_input_orphan_p)(struct ifnet *ifp, struct mbuf *m, int af);
99 void	(*ng_gif_attach_p)(struct ifnet *ifp);
100 void	(*ng_gif_detach_p)(struct ifnet *ifp);
101 
102 static int	gif_clone_create(struct if_clone *, int);
103 static void	gif_clone_destroy(struct ifnet *);
104 
105 IFC_SIMPLE_DECLARE(gif, 0);
106 
107 static int gifmodevent(module_t, int, void *);
108 
109 SYSCTL_DECL(_net_link);
110 SYSCTL_NODE(_net_link, IFT_GIF, gif, CTLFLAG_RW, 0,
111     "Generic Tunnel Interface");
112 #ifndef MAX_GIF_NEST
113 /*
114  * This macro controls the default upper limitation on nesting of gif tunnels.
115  * Since, setting a large value to this macro with a careless configuration
116  * may introduce system crash, we don't allow any nestings by default.
117  * If you need to configure nested gif tunnels, you can define this macro
118  * in your kernel configuration file.  However, if you do so, please be
119  * careful to configure the tunnels so that it won't make a loop.
120  */
121 #define MAX_GIF_NEST 1
122 #endif
123 static int max_gif_nesting = MAX_GIF_NEST;
124 SYSCTL_INT(_net_link_gif, OID_AUTO, max_nesting, CTLFLAG_RW,
125     &max_gif_nesting, 0, "Max nested tunnels");
126 
127 /*
128  * By default, we disallow creation of multiple tunnels between the same
129  * pair of addresses.  Some applications require this functionality so
130  * we allow control over this check here.
131  */
132 #ifdef XBONEHACK
133 static int parallel_tunnels = 1;
134 #else
135 static int parallel_tunnels = 0;
136 #endif
137 SYSCTL_INT(_net_link_gif, OID_AUTO, parallel_tunnels, CTLFLAG_RW,
138     &parallel_tunnels, 0, "Allow parallel tunnels?");
139 
140 static int
141 gif_clone_create(ifc, unit)
142 	struct if_clone *ifc;
143 	int unit;
144 {
145 	struct gif_softc *sc;
146 
147 	sc = malloc(sizeof(struct gif_softc), M_GIF, M_WAITOK | M_ZERO);
148 	GIF2IFP(sc) = if_alloc(IFT_GIF);
149 	if (GIF2IFP(sc) == NULL) {
150 		free(sc, M_GIF);
151 		return (ENOSPC);
152 	}
153 
154 	GIF2IFP(sc)->if_softc = sc;
155 	if_initname(GIF2IFP(sc), ifc->ifc_name, unit);
156 
157 	gifattach0(sc);
158 
159 	mtx_lock(&gif_mtx);
160 	LIST_INSERT_HEAD(&gif_softc_list, sc, gif_list);
161 	mtx_unlock(&gif_mtx);
162 	return (0);
163 }
164 
165 void
166 gifattach0(sc)
167 	struct gif_softc *sc;
168 {
169 
170 	sc->encap_cookie4 = sc->encap_cookie6 = NULL;
171 
172 	GIF2IFP(sc)->if_addrlen = 0;
173 	GIF2IFP(sc)->if_mtu    = GIF_MTU;
174 	GIF2IFP(sc)->if_flags  = IFF_POINTOPOINT | IFF_MULTICAST;
175 #if 0
176 	/* turn off ingress filter */
177 	GIF2IFP(sc)->if_flags  |= IFF_LINK2;
178 #endif
179 	GIF2IFP(sc)->if_ioctl  = gif_ioctl;
180 	GIF2IFP(sc)->if_output = gif_output;
181 	GIF2IFP(sc)->if_snd.ifq_maxlen = IFQ_MAXLEN;
182 	if_attach(GIF2IFP(sc));
183 	bpfattach(GIF2IFP(sc), DLT_NULL, sizeof(u_int32_t));
184 	if (ng_gif_attach_p != NULL)
185 		(*ng_gif_attach_p)(GIF2IFP(sc));
186 }
187 
188 static void
189 gif_clone_destroy(ifp)
190 	struct ifnet *ifp;
191 {
192 	int err;
193 	struct gif_softc *sc = ifp->if_softc;
194 
195 	mtx_lock(&gif_mtx);
196 	LIST_REMOVE(sc, gif_list);
197 	mtx_unlock(&gif_mtx);
198 
199 	gif_delete_tunnel(ifp);
200 #ifdef INET6
201 	if (sc->encap_cookie6 != NULL) {
202 		err = encap_detach(sc->encap_cookie6);
203 		KASSERT(err == 0, ("Unexpected error detaching encap_cookie6"));
204 	}
205 #endif
206 #ifdef INET
207 	if (sc->encap_cookie4 != NULL) {
208 		err = encap_detach(sc->encap_cookie4);
209 		KASSERT(err == 0, ("Unexpected error detaching encap_cookie4"));
210 	}
211 #endif
212 
213 	if (ng_gif_detach_p != NULL)
214 		(*ng_gif_detach_p)(ifp);
215 	bpfdetach(ifp);
216 	if_detach(ifp);
217 	if_free(ifp);
218 
219 	free(sc, M_GIF);
220 }
221 
222 static int
223 gifmodevent(mod, type, data)
224 	module_t mod;
225 	int type;
226 	void *data;
227 {
228 	struct gif_softc *sc;
229 
230 	switch (type) {
231 	case MOD_LOAD:
232 		mtx_init(&gif_mtx, "gif_mtx", NULL, MTX_DEF);
233 		LIST_INIT(&gif_softc_list);
234 		if_clone_attach(&gif_cloner);
235 
236 #ifdef INET6
237 		ip6_gif_hlim = GIF_HLIM;
238 #endif
239 
240 		break;
241 	case MOD_UNLOAD:
242 		if_clone_detach(&gif_cloner);
243 
244 		mtx_lock(&gif_mtx);
245 		while ((sc = LIST_FIRST(&gif_softc_list)) != NULL) {
246 			mtx_unlock(&gif_mtx);
247 			ifc_simple_destroy(&gif_cloner, GIF2IFP(sc));
248 			mtx_lock(&gif_mtx);
249 		}
250 		mtx_unlock(&gif_mtx);
251 		mtx_destroy(&gif_mtx);
252 #ifdef INET6
253 		ip6_gif_hlim = 0;
254 #endif
255 		break;
256 	default:
257 		return EOPNOTSUPP;
258 	}
259 	return 0;
260 }
261 
262 static moduledata_t gif_mod = {
263 	"if_gif",
264 	gifmodevent,
265 	0
266 };
267 
268 DECLARE_MODULE(if_gif, gif_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
269 MODULE_VERSION(if_gif, 1);
270 
271 int
272 gif_encapcheck(m, off, proto, arg)
273 	const struct mbuf *m;
274 	int off;
275 	int proto;
276 	void *arg;
277 {
278 	struct ip ip;
279 	struct gif_softc *sc;
280 
281 	sc = (struct gif_softc *)arg;
282 	if (sc == NULL)
283 		return 0;
284 
285 	if ((GIF2IFP(sc)->if_flags & IFF_UP) == 0)
286 		return 0;
287 
288 	/* no physical address */
289 	if (!sc->gif_psrc || !sc->gif_pdst)
290 		return 0;
291 
292 	switch (proto) {
293 #ifdef INET
294 	case IPPROTO_IPV4:
295 		break;
296 #endif
297 #ifdef INET6
298 	case IPPROTO_IPV6:
299 		break;
300 #endif
301 	default:
302 		return 0;
303 	}
304 
305 	/* Bail on short packets */
306 	if (m->m_pkthdr.len < sizeof(ip))
307 		return 0;
308 
309 	m_copydata(m, 0, sizeof(ip), (caddr_t)&ip);
310 
311 	switch (ip.ip_v) {
312 #ifdef INET
313 	case 4:
314 		if (sc->gif_psrc->sa_family != AF_INET ||
315 		    sc->gif_pdst->sa_family != AF_INET)
316 			return 0;
317 		return gif_encapcheck4(m, off, proto, arg);
318 #endif
319 #ifdef INET6
320 	case 6:
321 		if (m->m_pkthdr.len < sizeof(struct ip6_hdr))
322 			return 0;
323 		if (sc->gif_psrc->sa_family != AF_INET6 ||
324 		    sc->gif_pdst->sa_family != AF_INET6)
325 			return 0;
326 		return gif_encapcheck6(m, off, proto, arg);
327 #endif
328 	default:
329 		return 0;
330 	}
331 }
332 
333 int
334 gif_output(ifp, m, dst, rt)
335 	struct ifnet *ifp;
336 	struct mbuf *m;
337 	struct sockaddr *dst;
338 	struct rtentry *rt;	/* added in net2 */
339 {
340 	struct gif_softc *sc = ifp->if_softc;
341 	struct m_tag *mtag;
342 	int error = 0;
343 	int gif_called;
344 	u_int32_t af;
345 
346 #ifdef MAC
347 	error = mac_check_ifnet_transmit(ifp, m);
348 	if (error) {
349 		m_freem(m);
350 		goto end;
351 	}
352 #endif
353 
354 	/*
355 	 * gif may cause infinite recursion calls when misconfigured.
356 	 * We'll prevent this by detecting loops.
357 	 *
358 	 * High nesting level may cause stack exhaustion.
359 	 * We'll prevent this by introducing upper limit.
360 	 */
361 	gif_called = 1;
362 	mtag = m_tag_locate(m, MTAG_GIF, MTAG_GIF_CALLED, NULL);
363 	while (mtag != NULL) {
364 		if (*(struct ifnet **)(mtag + 1) == ifp) {
365 			log(LOG_NOTICE,
366 			    "gif_output: loop detected on %s\n",
367 			    (*(struct ifnet **)(mtag + 1))->if_xname);
368 			m_freem(m);
369 			error = EIO;	/* is there better errno? */
370 			goto end;
371 		}
372 		mtag = m_tag_locate(m, MTAG_GIF, MTAG_GIF_CALLED, mtag);
373 		gif_called++;
374 	}
375 	if (gif_called > max_gif_nesting) {
376 		log(LOG_NOTICE,
377 		    "gif_output: recursively called too many times(%d)\n",
378 		    gif_called);
379 		m_freem(m);
380 		error = EIO;	/* is there better errno? */
381 		goto end;
382 	}
383 	mtag = m_tag_alloc(MTAG_GIF, MTAG_GIF_CALLED, sizeof(struct ifnet *),
384 	    M_NOWAIT);
385 	if (mtag == NULL) {
386 		m_freem(m);
387 		error = ENOMEM;
388 		goto end;
389 	}
390 	*(struct ifnet **)(mtag + 1) = ifp;
391 	m_tag_prepend(m, mtag);
392 
393 	m->m_flags &= ~(M_BCAST|M_MCAST);
394 	if (!(ifp->if_flags & IFF_UP) ||
395 	    sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
396 		m_freem(m);
397 		error = ENETDOWN;
398 		goto end;
399 	}
400 
401 	/* BPF writes need to be handled specially. */
402 	if (dst->sa_family == AF_UNSPEC) {
403 		bcopy(dst->sa_data, &af, sizeof(af));
404 		dst->sa_family = af;
405 	}
406 
407 	if (ifp->if_bpf) {
408 		af = dst->sa_family;
409 		bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
410 	}
411 	ifp->if_opackets++;
412 	ifp->if_obytes += m->m_pkthdr.len;
413 
414 	/* inner AF-specific encapsulation */
415 
416 	/* XXX should we check if our outer source is legal? */
417 
418 	/* dispatch to output logic based on outer AF */
419 	switch (sc->gif_psrc->sa_family) {
420 #ifdef INET
421 	case AF_INET:
422 		error = in_gif_output(ifp, dst->sa_family, m);
423 		break;
424 #endif
425 #ifdef INET6
426 	case AF_INET6:
427 		error = in6_gif_output(ifp, dst->sa_family, m);
428 		break;
429 #endif
430 	default:
431 		m_freem(m);
432 		error = ENETDOWN;
433 		goto end;
434 	}
435 
436   end:
437 	if (error)
438 		ifp->if_oerrors++;
439 	return error;
440 }
441 
442 void
443 gif_input(m, af, ifp)
444 	struct mbuf *m;
445 	int af;
446 	struct ifnet *ifp;
447 {
448 	int isr;
449 
450 	if (ifp == NULL) {
451 		/* just in case */
452 		m_freem(m);
453 		return;
454 	}
455 
456 	m->m_pkthdr.rcvif = ifp;
457 
458 #ifdef MAC
459 	mac_create_mbuf_from_ifnet(ifp, m);
460 #endif
461 
462 	if (ifp->if_bpf) {
463 		u_int32_t af1 = af;
464 		bpf_mtap2(ifp->if_bpf, &af1, sizeof(af1), m);
465 	}
466 
467 	if (ng_gif_input_p != NULL) {
468 		(*ng_gif_input_p)(ifp, &m, af);
469 		if (m == NULL)
470 			return;
471 	}
472 
473 	/*
474 	 * Put the packet to the network layer input queue according to the
475 	 * specified address family.
476 	 * Note: older versions of gif_input directly called network layer
477 	 * input functions, e.g. ip6_input, here.  We changed the policy to
478 	 * prevent too many recursive calls of such input functions, which
479 	 * might cause kernel panic.  But the change may introduce another
480 	 * problem; if the input queue is full, packets are discarded.
481 	 * The kernel stack overflow really happened, and we believed
482 	 * queue-full rarely occurs, so we changed the policy.
483 	 */
484 	switch (af) {
485 #ifdef INET
486 	case AF_INET:
487 		isr = NETISR_IP;
488 		break;
489 #endif
490 #ifdef INET6
491 	case AF_INET6:
492 		isr = NETISR_IPV6;
493 		break;
494 #endif
495 	default:
496 		if (ng_gif_input_orphan_p != NULL)
497 			(*ng_gif_input_orphan_p)(ifp, m, af);
498 		else
499 			m_freem(m);
500 		return;
501 	}
502 
503 	ifp->if_ipackets++;
504 	ifp->if_ibytes += m->m_pkthdr.len;
505 	netisr_dispatch(isr, m);
506 }
507 
508 /* XXX how should we handle IPv6 scope on SIOC[GS]IFPHYADDR? */
509 int
510 gif_ioctl(ifp, cmd, data)
511 	struct ifnet *ifp;
512 	u_long cmd;
513 	caddr_t data;
514 {
515 	struct gif_softc *sc  = ifp->if_softc;
516 	struct ifreq     *ifr = (struct ifreq*)data;
517 	int error = 0, size;
518 	struct sockaddr *dst, *src;
519 #ifdef	SIOCSIFMTU /* xxx */
520 	u_long mtu;
521 #endif
522 
523 	switch (cmd) {
524 	case SIOCSIFADDR:
525 		ifp->if_flags |= IFF_UP;
526 		break;
527 
528 	case SIOCSIFDSTADDR:
529 		break;
530 
531 	case SIOCADDMULTI:
532 	case SIOCDELMULTI:
533 		break;
534 
535 #ifdef	SIOCSIFMTU /* xxx */
536 	case SIOCGIFMTU:
537 		break;
538 
539 	case SIOCSIFMTU:
540 		mtu = ifr->ifr_mtu;
541 		if (mtu < GIF_MTU_MIN || mtu > GIF_MTU_MAX)
542 			return (EINVAL);
543 		ifp->if_mtu = mtu;
544 		break;
545 #endif /* SIOCSIFMTU */
546 
547 #ifdef INET
548 	case SIOCSIFPHYADDR:
549 #endif
550 #ifdef INET6
551 	case SIOCSIFPHYADDR_IN6:
552 #endif /* INET6 */
553 	case SIOCSLIFPHYADDR:
554 		switch (cmd) {
555 #ifdef INET
556 		case SIOCSIFPHYADDR:
557 			src = (struct sockaddr *)
558 				&(((struct in_aliasreq *)data)->ifra_addr);
559 			dst = (struct sockaddr *)
560 				&(((struct in_aliasreq *)data)->ifra_dstaddr);
561 			break;
562 #endif
563 #ifdef INET6
564 		case SIOCSIFPHYADDR_IN6:
565 			src = (struct sockaddr *)
566 				&(((struct in6_aliasreq *)data)->ifra_addr);
567 			dst = (struct sockaddr *)
568 				&(((struct in6_aliasreq *)data)->ifra_dstaddr);
569 			break;
570 #endif
571 		case SIOCSLIFPHYADDR:
572 			src = (struct sockaddr *)
573 				&(((struct if_laddrreq *)data)->addr);
574 			dst = (struct sockaddr *)
575 				&(((struct if_laddrreq *)data)->dstaddr);
576 			break;
577 		default:
578 			return EINVAL;
579 		}
580 
581 		/* sa_family must be equal */
582 		if (src->sa_family != dst->sa_family)
583 			return EINVAL;
584 
585 		/* validate sa_len */
586 		switch (src->sa_family) {
587 #ifdef INET
588 		case AF_INET:
589 			if (src->sa_len != sizeof(struct sockaddr_in))
590 				return EINVAL;
591 			break;
592 #endif
593 #ifdef INET6
594 		case AF_INET6:
595 			if (src->sa_len != sizeof(struct sockaddr_in6))
596 				return EINVAL;
597 			break;
598 #endif
599 		default:
600 			return EAFNOSUPPORT;
601 		}
602 		switch (dst->sa_family) {
603 #ifdef INET
604 		case AF_INET:
605 			if (dst->sa_len != sizeof(struct sockaddr_in))
606 				return EINVAL;
607 			break;
608 #endif
609 #ifdef INET6
610 		case AF_INET6:
611 			if (dst->sa_len != sizeof(struct sockaddr_in6))
612 				return EINVAL;
613 			break;
614 #endif
615 		default:
616 			return EAFNOSUPPORT;
617 		}
618 
619 		/* check sa_family looks sane for the cmd */
620 		switch (cmd) {
621 		case SIOCSIFPHYADDR:
622 			if (src->sa_family == AF_INET)
623 				break;
624 			return EAFNOSUPPORT;
625 #ifdef INET6
626 		case SIOCSIFPHYADDR_IN6:
627 			if (src->sa_family == AF_INET6)
628 				break;
629 			return EAFNOSUPPORT;
630 #endif /* INET6 */
631 		case SIOCSLIFPHYADDR:
632 			/* checks done in the above */
633 			break;
634 		}
635 
636 		error = gif_set_tunnel(GIF2IFP(sc), src, dst);
637 		break;
638 
639 #ifdef SIOCDIFPHYADDR
640 	case SIOCDIFPHYADDR:
641 		gif_delete_tunnel(GIF2IFP(sc));
642 		break;
643 #endif
644 
645 	case SIOCGIFPSRCADDR:
646 #ifdef INET6
647 	case SIOCGIFPSRCADDR_IN6:
648 #endif /* INET6 */
649 		if (sc->gif_psrc == NULL) {
650 			error = EADDRNOTAVAIL;
651 			goto bad;
652 		}
653 		src = sc->gif_psrc;
654 		switch (cmd) {
655 #ifdef INET
656 		case SIOCGIFPSRCADDR:
657 			dst = &ifr->ifr_addr;
658 			size = sizeof(ifr->ifr_addr);
659 			break;
660 #endif /* INET */
661 #ifdef INET6
662 		case SIOCGIFPSRCADDR_IN6:
663 			dst = (struct sockaddr *)
664 				&(((struct in6_ifreq *)data)->ifr_addr);
665 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
666 			break;
667 #endif /* INET6 */
668 		default:
669 			error = EADDRNOTAVAIL;
670 			goto bad;
671 		}
672 		if (src->sa_len > size)
673 			return EINVAL;
674 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
675 #ifdef INET6
676 		if (dst->sa_family == AF_INET6) {
677 			error = sa6_recoverscope((struct sockaddr_in6 *)dst);
678 			if (error != 0)
679 				return (error);
680 		}
681 #endif
682 		break;
683 
684 	case SIOCGIFPDSTADDR:
685 #ifdef INET6
686 	case SIOCGIFPDSTADDR_IN6:
687 #endif /* INET6 */
688 		if (sc->gif_pdst == NULL) {
689 			error = EADDRNOTAVAIL;
690 			goto bad;
691 		}
692 		src = sc->gif_pdst;
693 		switch (cmd) {
694 #ifdef INET
695 		case SIOCGIFPDSTADDR:
696 			dst = &ifr->ifr_addr;
697 			size = sizeof(ifr->ifr_addr);
698 			break;
699 #endif /* INET */
700 #ifdef INET6
701 		case SIOCGIFPDSTADDR_IN6:
702 			dst = (struct sockaddr *)
703 				&(((struct in6_ifreq *)data)->ifr_addr);
704 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
705 			break;
706 #endif /* INET6 */
707 		default:
708 			error = EADDRNOTAVAIL;
709 			goto bad;
710 		}
711 		if (src->sa_len > size)
712 			return EINVAL;
713 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
714 #ifdef INET6
715 		if (dst->sa_family == AF_INET6) {
716 			error = sa6_recoverscope((struct sockaddr_in6 *)dst);
717 			if (error != 0)
718 				return (error);
719 		}
720 #endif
721 		break;
722 
723 	case SIOCGLIFPHYADDR:
724 		if (sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
725 			error = EADDRNOTAVAIL;
726 			goto bad;
727 		}
728 
729 		/* copy src */
730 		src = sc->gif_psrc;
731 		dst = (struct sockaddr *)
732 			&(((struct if_laddrreq *)data)->addr);
733 		size = sizeof(((struct if_laddrreq *)data)->addr);
734 		if (src->sa_len > size)
735 			return EINVAL;
736 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
737 
738 		/* copy dst */
739 		src = sc->gif_pdst;
740 		dst = (struct sockaddr *)
741 			&(((struct if_laddrreq *)data)->dstaddr);
742 		size = sizeof(((struct if_laddrreq *)data)->dstaddr);
743 		if (src->sa_len > size)
744 			return EINVAL;
745 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
746 		break;
747 
748 	case SIOCSIFFLAGS:
749 		/* if_ioctl() takes care of it */
750 		break;
751 
752 	default:
753 		error = EINVAL;
754 		break;
755 	}
756  bad:
757 	return error;
758 }
759 
760 /*
761  * XXXRW: There's a general event-ordering issue here: the code to check
762  * if a given tunnel is already present happens before we perform a
763  * potentially blocking setup of the tunnel.  This code needs to be
764  * re-ordered so that the check and replacement can be atomic using
765  * a mutex.
766  */
767 int
768 gif_set_tunnel(ifp, src, dst)
769 	struct ifnet *ifp;
770 	struct sockaddr *src;
771 	struct sockaddr *dst;
772 {
773 	struct gif_softc *sc = ifp->if_softc;
774 	struct gif_softc *sc2;
775 	struct sockaddr *osrc, *odst, *sa;
776 	int s;
777 	int error = 0;
778 
779 	s = splnet();
780 
781 	mtx_lock(&gif_mtx);
782 	LIST_FOREACH(sc2, &gif_softc_list, gif_list) {
783 		if (sc2 == sc)
784 			continue;
785 		if (!sc2->gif_pdst || !sc2->gif_psrc)
786 			continue;
787 		if (sc2->gif_pdst->sa_family != dst->sa_family ||
788 		    sc2->gif_pdst->sa_len != dst->sa_len ||
789 		    sc2->gif_psrc->sa_family != src->sa_family ||
790 		    sc2->gif_psrc->sa_len != src->sa_len)
791 			continue;
792 
793 		/*
794 		 * Disallow parallel tunnels unless instructed
795 		 * otherwise.
796 		 */
797 		if (!parallel_tunnels &&
798 		    bcmp(sc2->gif_pdst, dst, dst->sa_len) == 0 &&
799 		    bcmp(sc2->gif_psrc, src, src->sa_len) == 0) {
800 			error = EADDRNOTAVAIL;
801 			mtx_unlock(&gif_mtx);
802 			goto bad;
803 		}
804 
805 		/* XXX both end must be valid? (I mean, not 0.0.0.0) */
806 	}
807 	mtx_unlock(&gif_mtx);
808 
809 	/* XXX we can detach from both, but be polite just in case */
810 	if (sc->gif_psrc)
811 		switch (sc->gif_psrc->sa_family) {
812 #ifdef INET
813 		case AF_INET:
814 			(void)in_gif_detach(sc);
815 			break;
816 #endif
817 #ifdef INET6
818 		case AF_INET6:
819 			(void)in6_gif_detach(sc);
820 			break;
821 #endif
822 		}
823 
824 	osrc = sc->gif_psrc;
825 	sa = (struct sockaddr *)malloc(src->sa_len, M_IFADDR, M_WAITOK);
826 	bcopy((caddr_t)src, (caddr_t)sa, src->sa_len);
827 	sc->gif_psrc = sa;
828 
829 	odst = sc->gif_pdst;
830 	sa = (struct sockaddr *)malloc(dst->sa_len, M_IFADDR, M_WAITOK);
831 	bcopy((caddr_t)dst, (caddr_t)sa, dst->sa_len);
832 	sc->gif_pdst = sa;
833 
834 	switch (sc->gif_psrc->sa_family) {
835 #ifdef INET
836 	case AF_INET:
837 		error = in_gif_attach(sc);
838 		break;
839 #endif
840 #ifdef INET6
841 	case AF_INET6:
842 		/*
843 		 * Check validity of the scope zone ID of the addresses, and
844 		 * convert it into the kernel internal form if necessary.
845 		 */
846 		error = sa6_embedscope((struct sockaddr_in6 *)sc->gif_psrc, 0);
847 		if (error != 0)
848 			break;
849 		error = sa6_embedscope((struct sockaddr_in6 *)sc->gif_pdst, 0);
850 		if (error != 0)
851 			break;
852 		error = in6_gif_attach(sc);
853 		break;
854 #endif
855 	}
856 	if (error) {
857 		/* rollback */
858 		free((caddr_t)sc->gif_psrc, M_IFADDR);
859 		free((caddr_t)sc->gif_pdst, M_IFADDR);
860 		sc->gif_psrc = osrc;
861 		sc->gif_pdst = odst;
862 		goto bad;
863 	}
864 
865 	if (osrc)
866 		free((caddr_t)osrc, M_IFADDR);
867 	if (odst)
868 		free((caddr_t)odst, M_IFADDR);
869 
870 	if (sc->gif_psrc && sc->gif_pdst)
871 		ifp->if_drv_flags |= IFF_DRV_RUNNING;
872 	else
873 		ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
874 	splx(s);
875 
876 	return 0;
877 
878  bad:
879 	if (sc->gif_psrc && sc->gif_pdst)
880 		ifp->if_drv_flags |= IFF_DRV_RUNNING;
881 	else
882 		ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
883 	splx(s);
884 
885 	return error;
886 }
887 
888 void
889 gif_delete_tunnel(ifp)
890 	struct ifnet *ifp;
891 {
892 	struct gif_softc *sc = ifp->if_softc;
893 	int s;
894 
895 	s = splnet();
896 
897 	if (sc->gif_psrc) {
898 		free((caddr_t)sc->gif_psrc, M_IFADDR);
899 		sc->gif_psrc = NULL;
900 	}
901 	if (sc->gif_pdst) {
902 		free((caddr_t)sc->gif_pdst, M_IFADDR);
903 		sc->gif_pdst = NULL;
904 	}
905 	/* it is safe to detach from both */
906 #ifdef INET
907 	(void)in_gif_detach(sc);
908 #endif
909 #ifdef INET6
910 	(void)in6_gif_detach(sc);
911 #endif
912 
913 	if (sc->gif_psrc && sc->gif_pdst)
914 		ifp->if_drv_flags |= IFF_DRV_RUNNING;
915 	else
916 		ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
917 	splx(s);
918 }
919