if_gif.c revision 147611 
1/*	$FreeBSD: head/sys/net/if_gif.c 147611 2005-06-26 18:11:11Z dwmalone $	*/
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/in6_gif.h>
78#include <netinet6/ip6protosw.h>
79#endif /* INET6 */
80
81#include <netinet/ip_encap.h>
82#include <net/if_gif.h>
83
84#include <net/net_osdep.h>
85
86#define GIFNAME		"gif"
87
88/*
89 * gif_mtx protects the global gif_softc_list.
90 * XXX: Per-softc locking is still required.
91 */
92static struct mtx gif_mtx;
93static MALLOC_DEFINE(M_GIF, "gif", "Generic Tunnel Interface");
94static LIST_HEAD(, gif_softc) gif_softc_list;
95
96void	(*ng_gif_input_p)(struct ifnet *ifp, struct mbuf **mp, int af);
97void	(*ng_gif_input_orphan_p)(struct ifnet *ifp, struct mbuf *m, int af);
98void	(*ng_gif_attach_p)(struct ifnet *ifp);
99void	(*ng_gif_detach_p)(struct ifnet *ifp);
100
101static int	gif_clone_create(struct if_clone *, int);
102static void	gif_clone_destroy(struct ifnet *);
103
104IFC_SIMPLE_DECLARE(gif, 0);
105
106static int gifmodevent(module_t, int, void *);
107
108SYSCTL_DECL(_net_link);
109SYSCTL_NODE(_net_link, IFT_GIF, gif, CTLFLAG_RW, 0,
110    "Generic Tunnel Interface");
111#ifndef MAX_GIF_NEST
112/*
113 * This macro controls the default upper limitation on nesting of gif tunnels.
114 * Since, setting a large value to this macro with a careless configuration
115 * may introduce system crash, we don't allow any nestings by default.
116 * If you need to configure nested gif tunnels, you can define this macro
117 * in your kernel configuration file.  However, if you do so, please be
118 * careful to configure the tunnels so that it won't make a loop.
119 */
120#define MAX_GIF_NEST 1
121#endif
122static int max_gif_nesting = MAX_GIF_NEST;
123SYSCTL_INT(_net_link_gif, OID_AUTO, max_nesting, CTLFLAG_RW,
124    &max_gif_nesting, 0, "Max nested tunnels");
125
126/*
127 * By default, we disallow creation of multiple tunnels between the same
128 * pair of addresses.  Some applications require this functionality so
129 * we allow control over this check here.
130 */
131#ifdef XBONEHACK
132static int parallel_tunnels = 1;
133#else
134static int parallel_tunnels = 0;
135#endif
136SYSCTL_INT(_net_link_gif, OID_AUTO, parallel_tunnels, CTLFLAG_RW,
137    &parallel_tunnels, 0, "Allow parallel tunnels?");
138
139static int
140gif_clone_create(ifc, unit)
141	struct if_clone *ifc;
142	int unit;
143{
144	struct gif_softc *sc;
145
146	sc = malloc(sizeof(struct gif_softc), M_GIF, M_WAITOK | M_ZERO);
147	GIF2IFP(sc) = if_alloc(IFT_GIF);
148	if (GIF2IFP(sc) == NULL) {
149		free(sc, M_GIF);
150		return (ENOSPC);
151	}
152
153	GIF2IFP(sc)->if_softc = sc;
154	if_initname(GIF2IFP(sc), ifc->ifc_name, unit);
155
156	gifattach0(sc);
157
158	mtx_lock(&gif_mtx);
159	LIST_INSERT_HEAD(&gif_softc_list, sc, gif_list);
160	mtx_unlock(&gif_mtx);
161	return (0);
162}
163
164void
165gifattach0(sc)
166	struct gif_softc *sc;
167{
168
169	sc->encap_cookie4 = sc->encap_cookie6 = NULL;
170
171	GIF2IFP(sc)->if_addrlen = 0;
172	GIF2IFP(sc)->if_mtu    = GIF_MTU;
173	GIF2IFP(sc)->if_flags  = IFF_POINTOPOINT | IFF_MULTICAST;
174#if 0
175	/* turn off ingress filter */
176	GIF2IFP(sc)->if_flags  |= IFF_LINK2;
177#endif
178	GIF2IFP(sc)->if_ioctl  = gif_ioctl;
179	GIF2IFP(sc)->if_output = gif_output;
180	GIF2IFP(sc)->if_snd.ifq_maxlen = IFQ_MAXLEN;
181	if_attach(GIF2IFP(sc));
182	bpfattach(GIF2IFP(sc), DLT_NULL, sizeof(u_int32_t));
183	if (ng_gif_attach_p != NULL)
184		(*ng_gif_attach_p)(GIF2IFP(sc));
185}
186
187static void
188gif_destroy(struct gif_softc *sc)
189{
190	struct ifnet *ifp = GIF2IFP(sc);
191	int err;
192
193	gif_delete_tunnel(ifp);
194#ifdef INET6
195	if (sc->encap_cookie6 != NULL) {
196		err = encap_detach(sc->encap_cookie6);
197		KASSERT(err == 0, ("Unexpected error detaching encap_cookie6"));
198	}
199#endif
200#ifdef INET
201	if (sc->encap_cookie4 != NULL) {
202		err = encap_detach(sc->encap_cookie4);
203		KASSERT(err == 0, ("Unexpected error detaching encap_cookie4"));
204	}
205#endif
206
207	if (ng_gif_detach_p != NULL)
208		(*ng_gif_detach_p)(ifp);
209	bpfdetach(ifp);
210	if_detach(ifp);
211	if_free(ifp);
212
213	free(sc, M_GIF);
214}
215
216static void
217gif_clone_destroy(ifp)
218	struct ifnet *ifp;
219{
220	struct gif_softc *sc = ifp->if_softc;
221
222	mtx_lock(&gif_mtx);
223	LIST_REMOVE(sc, gif_list);
224	mtx_unlock(&gif_mtx);
225	gif_destroy(sc);
226}
227
228static int
229gifmodevent(mod, type, data)
230	module_t mod;
231	int type;
232	void *data;
233{
234	struct gif_softc *sc;
235
236	switch (type) {
237	case MOD_LOAD:
238		mtx_init(&gif_mtx, "gif_mtx", NULL, MTX_DEF);
239		LIST_INIT(&gif_softc_list);
240		if_clone_attach(&gif_cloner);
241
242#ifdef INET6
243		ip6_gif_hlim = GIF_HLIM;
244#endif
245
246		break;
247	case MOD_UNLOAD:
248		if_clone_detach(&gif_cloner);
249
250		mtx_lock(&gif_mtx);
251		while ((sc = LIST_FIRST(&gif_softc_list)) != NULL) {
252			LIST_REMOVE(sc, gif_list);
253			mtx_unlock(&gif_mtx);
254			gif_destroy(sc);
255			mtx_lock(&gif_mtx);
256		}
257		mtx_unlock(&gif_mtx);
258		mtx_destroy(&gif_mtx);
259#ifdef INET6
260		ip6_gif_hlim = 0;
261#endif
262		break;
263	default:
264		return EOPNOTSUPP;
265	}
266	return 0;
267}
268
269static moduledata_t gif_mod = {
270	"if_gif",
271	gifmodevent,
272	0
273};
274
275DECLARE_MODULE(if_gif, gif_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
276MODULE_VERSION(if_gif, 1);
277
278int
279gif_encapcheck(m, off, proto, arg)
280	const struct mbuf *m;
281	int off;
282	int proto;
283	void *arg;
284{
285	struct ip ip;
286	struct gif_softc *sc;
287
288	sc = (struct gif_softc *)arg;
289	if (sc == NULL)
290		return 0;
291
292	if ((GIF2IFP(sc)->if_flags & IFF_UP) == 0)
293		return 0;
294
295	/* no physical address */
296	if (!sc->gif_psrc || !sc->gif_pdst)
297		return 0;
298
299	switch (proto) {
300#ifdef INET
301	case IPPROTO_IPV4:
302		break;
303#endif
304#ifdef INET6
305	case IPPROTO_IPV6:
306		break;
307#endif
308	default:
309		return 0;
310	}
311
312	/* Bail on short packets */
313	if (m->m_pkthdr.len < sizeof(ip))
314		return 0;
315
316	m_copydata(m, 0, sizeof(ip), (caddr_t)&ip);
317
318	switch (ip.ip_v) {
319#ifdef INET
320	case 4:
321		if (sc->gif_psrc->sa_family != AF_INET ||
322		    sc->gif_pdst->sa_family != AF_INET)
323			return 0;
324		return gif_encapcheck4(m, off, proto, arg);
325#endif
326#ifdef INET6
327	case 6:
328		if (m->m_pkthdr.len < sizeof(struct ip6_hdr))
329			return 0;
330		if (sc->gif_psrc->sa_family != AF_INET6 ||
331		    sc->gif_pdst->sa_family != AF_INET6)
332			return 0;
333		return gif_encapcheck6(m, off, proto, arg);
334#endif
335	default:
336		return 0;
337	}
338}
339
340int
341gif_output(ifp, m, dst, rt)
342	struct ifnet *ifp;
343	struct mbuf *m;
344	struct sockaddr *dst;
345	struct rtentry *rt;	/* added in net2 */
346{
347	struct gif_softc *sc = ifp->if_softc;
348	struct m_tag *mtag;
349	int error = 0;
350	int gif_called;
351	u_int32_t af;
352
353#ifdef MAC
354	error = mac_check_ifnet_transmit(ifp, m);
355	if (error) {
356		m_freem(m);
357		goto end;
358	}
359#endif
360
361	/*
362	 * gif may cause infinite recursion calls when misconfigured.
363	 * We'll prevent this by detecting loops.
364	 *
365	 * High nesting level may cause stack exhaustion.
366	 * We'll prevent this by introducing upper limit.
367	 */
368	gif_called = 1;
369	mtag = m_tag_locate(m, MTAG_GIF, MTAG_GIF_CALLED, NULL);
370	while (mtag != NULL) {
371		if (*(struct ifnet **)(mtag + 1) == ifp) {
372			log(LOG_NOTICE,
373			    "gif_output: loop detected on %s\n",
374			    (*(struct ifnet **)(mtag + 1))->if_xname);
375			m_freem(m);
376			error = EIO;	/* is there better errno? */
377			goto end;
378		}
379		mtag = m_tag_locate(m, MTAG_GIF, MTAG_GIF_CALLED, mtag);
380		gif_called++;
381	}
382	if (gif_called > max_gif_nesting) {
383		log(LOG_NOTICE,
384		    "gif_output: recursively called too many times(%d)\n",
385		    gif_called);
386		m_freem(m);
387		error = EIO;	/* is there better errno? */
388		goto end;
389	}
390	mtag = m_tag_alloc(MTAG_GIF, MTAG_GIF_CALLED, sizeof(struct ifnet *),
391	    M_NOWAIT);
392	if (mtag == NULL) {
393		m_freem(m);
394		error = ENOMEM;
395		goto end;
396	}
397	*(struct ifnet **)(mtag + 1) = ifp;
398	m_tag_prepend(m, mtag);
399
400	m->m_flags &= ~(M_BCAST|M_MCAST);
401	if (!(ifp->if_flags & IFF_UP) ||
402	    sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
403		m_freem(m);
404		error = ENETDOWN;
405		goto end;
406	}
407
408	/* BPF writes need to be handled specially. */
409	if (dst->sa_family == AF_UNSPEC) {
410		bcopy(dst->sa_data, &af, sizeof(af));
411		dst->sa_family = af;
412	}
413
414	if (ifp->if_bpf) {
415		af = dst->sa_family;
416		bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
417	}
418	ifp->if_opackets++;
419	ifp->if_obytes += m->m_pkthdr.len;
420
421	/* inner AF-specific encapsulation */
422
423	/* XXX should we check if our outer source is legal? */
424
425	/* dispatch to output logic based on outer AF */
426	switch (sc->gif_psrc->sa_family) {
427#ifdef INET
428	case AF_INET:
429		error = in_gif_output(ifp, dst->sa_family, m);
430		break;
431#endif
432#ifdef INET6
433	case AF_INET6:
434		error = in6_gif_output(ifp, dst->sa_family, m);
435		break;
436#endif
437	default:
438		m_freem(m);
439		error = ENETDOWN;
440		goto end;
441	}
442
443  end:
444	if (error)
445		ifp->if_oerrors++;
446	return error;
447}
448
449void
450gif_input(m, af, ifp)
451	struct mbuf *m;
452	int af;
453	struct ifnet *ifp;
454{
455	int isr;
456
457	if (ifp == NULL) {
458		/* just in case */
459		m_freem(m);
460		return;
461	}
462
463	m->m_pkthdr.rcvif = ifp;
464
465#ifdef MAC
466	mac_create_mbuf_from_ifnet(ifp, m);
467#endif
468
469	if (ifp->if_bpf) {
470		u_int32_t af1 = af;
471		bpf_mtap2(ifp->if_bpf, &af1, sizeof(af1), m);
472	}
473
474	if (ng_gif_input_p != NULL) {
475		(*ng_gif_input_p)(ifp, &m, af);
476		if (m == NULL)
477			return;
478	}
479
480	/*
481	 * Put the packet to the network layer input queue according to the
482	 * specified address family.
483	 * Note: older versions of gif_input directly called network layer
484	 * input functions, e.g. ip6_input, here.  We changed the policy to
485	 * prevent too many recursive calls of such input functions, which
486	 * might cause kernel panic.  But the change may introduce another
487	 * problem; if the input queue is full, packets are discarded.
488	 * The kernel stack overflow really happened, and we believed
489	 * queue-full rarely occurs, so we changed the policy.
490	 */
491	switch (af) {
492#ifdef INET
493	case AF_INET:
494		isr = NETISR_IP;
495		break;
496#endif
497#ifdef INET6
498	case AF_INET6:
499		isr = NETISR_IPV6;
500		break;
501#endif
502	default:
503		if (ng_gif_input_orphan_p != NULL)
504			(*ng_gif_input_orphan_p)(ifp, m, af);
505		else
506			m_freem(m);
507		return;
508	}
509
510	ifp->if_ipackets++;
511	ifp->if_ibytes += m->m_pkthdr.len;
512	netisr_dispatch(isr, m);
513}
514
515/* XXX how should we handle IPv6 scope on SIOC[GS]IFPHYADDR? */
516int
517gif_ioctl(ifp, cmd, data)
518	struct ifnet *ifp;
519	u_long cmd;
520	caddr_t data;
521{
522	struct gif_softc *sc  = ifp->if_softc;
523	struct ifreq     *ifr = (struct ifreq*)data;
524	int error = 0, size;
525	struct sockaddr *dst, *src;
526#ifdef	SIOCSIFMTU /* xxx */
527	u_long mtu;
528#endif
529
530	switch (cmd) {
531	case SIOCSIFADDR:
532		ifp->if_flags |= IFF_UP;
533		break;
534
535	case SIOCSIFDSTADDR:
536		break;
537
538	case SIOCADDMULTI:
539	case SIOCDELMULTI:
540		break;
541
542#ifdef	SIOCSIFMTU /* xxx */
543	case SIOCGIFMTU:
544		break;
545
546	case SIOCSIFMTU:
547		mtu = ifr->ifr_mtu;
548		if (mtu < GIF_MTU_MIN || mtu > GIF_MTU_MAX)
549			return (EINVAL);
550		ifp->if_mtu = mtu;
551		break;
552#endif /* SIOCSIFMTU */
553
554#ifdef INET
555	case SIOCSIFPHYADDR:
556#endif
557#ifdef INET6
558	case SIOCSIFPHYADDR_IN6:
559#endif /* INET6 */
560	case SIOCSLIFPHYADDR:
561		switch (cmd) {
562#ifdef INET
563		case SIOCSIFPHYADDR:
564			src = (struct sockaddr *)
565				&(((struct in_aliasreq *)data)->ifra_addr);
566			dst = (struct sockaddr *)
567				&(((struct in_aliasreq *)data)->ifra_dstaddr);
568			break;
569#endif
570#ifdef INET6
571		case SIOCSIFPHYADDR_IN6:
572			src = (struct sockaddr *)
573				&(((struct in6_aliasreq *)data)->ifra_addr);
574			dst = (struct sockaddr *)
575				&(((struct in6_aliasreq *)data)->ifra_dstaddr);
576			break;
577#endif
578		case SIOCSLIFPHYADDR:
579			src = (struct sockaddr *)
580				&(((struct if_laddrreq *)data)->addr);
581			dst = (struct sockaddr *)
582				&(((struct if_laddrreq *)data)->dstaddr);
583			break;
584		default:
585			return EINVAL;
586		}
587
588		/* sa_family must be equal */
589		if (src->sa_family != dst->sa_family)
590			return EINVAL;
591
592		/* validate sa_len */
593		switch (src->sa_family) {
594#ifdef INET
595		case AF_INET:
596			if (src->sa_len != sizeof(struct sockaddr_in))
597				return EINVAL;
598			break;
599#endif
600#ifdef INET6
601		case AF_INET6:
602			if (src->sa_len != sizeof(struct sockaddr_in6))
603				return EINVAL;
604			break;
605#endif
606		default:
607			return EAFNOSUPPORT;
608		}
609		switch (dst->sa_family) {
610#ifdef INET
611		case AF_INET:
612			if (dst->sa_len != sizeof(struct sockaddr_in))
613				return EINVAL;
614			break;
615#endif
616#ifdef INET6
617		case AF_INET6:
618			if (dst->sa_len != sizeof(struct sockaddr_in6))
619				return EINVAL;
620			break;
621#endif
622		default:
623			return EAFNOSUPPORT;
624		}
625
626		/* check sa_family looks sane for the cmd */
627		switch (cmd) {
628		case SIOCSIFPHYADDR:
629			if (src->sa_family == AF_INET)
630				break;
631			return EAFNOSUPPORT;
632#ifdef INET6
633		case SIOCSIFPHYADDR_IN6:
634			if (src->sa_family == AF_INET6)
635				break;
636			return EAFNOSUPPORT;
637#endif /* INET6 */
638		case SIOCSLIFPHYADDR:
639			/* checks done in the above */
640			break;
641		}
642
643		error = gif_set_tunnel(GIF2IFP(sc), src, dst);
644		break;
645
646#ifdef SIOCDIFPHYADDR
647	case SIOCDIFPHYADDR:
648		gif_delete_tunnel(GIF2IFP(sc));
649		break;
650#endif
651
652	case SIOCGIFPSRCADDR:
653#ifdef INET6
654	case SIOCGIFPSRCADDR_IN6:
655#endif /* INET6 */
656		if (sc->gif_psrc == NULL) {
657			error = EADDRNOTAVAIL;
658			goto bad;
659		}
660		src = sc->gif_psrc;
661		switch (cmd) {
662#ifdef INET
663		case SIOCGIFPSRCADDR:
664			dst = &ifr->ifr_addr;
665			size = sizeof(ifr->ifr_addr);
666			break;
667#endif /* INET */
668#ifdef INET6
669		case SIOCGIFPSRCADDR_IN6:
670			dst = (struct sockaddr *)
671				&(((struct in6_ifreq *)data)->ifr_addr);
672			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
673			break;
674#endif /* INET6 */
675		default:
676			error = EADDRNOTAVAIL;
677			goto bad;
678		}
679		if (src->sa_len > size)
680			return EINVAL;
681		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
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		break;
715
716	case SIOCGLIFPHYADDR:
717		if (sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
718			error = EADDRNOTAVAIL;
719			goto bad;
720		}
721
722		/* copy src */
723		src = sc->gif_psrc;
724		dst = (struct sockaddr *)
725			&(((struct if_laddrreq *)data)->addr);
726		size = sizeof(((struct if_laddrreq *)data)->addr);
727		if (src->sa_len > size)
728			return EINVAL;
729		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
730
731		/* copy dst */
732		src = sc->gif_pdst;
733		dst = (struct sockaddr *)
734			&(((struct if_laddrreq *)data)->dstaddr);
735		size = sizeof(((struct if_laddrreq *)data)->dstaddr);
736		if (src->sa_len > size)
737			return EINVAL;
738		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
739		break;
740
741	case SIOCSIFFLAGS:
742		/* if_ioctl() takes care of it */
743		break;
744
745	default:
746		error = EINVAL;
747		break;
748	}
749 bad:
750	return error;
751}
752
753/*
754 * XXXRW: There's a general event-ordering issue here: the code to check
755 * if a given tunnel is already present happens before we perform a
756 * potentially blocking setup of the tunnel.  This code needs to be
757 * re-ordered so that the check and replacement can be atomic using
758 * a mutex.
759 */
760int
761gif_set_tunnel(ifp, src, dst)
762	struct ifnet *ifp;
763	struct sockaddr *src;
764	struct sockaddr *dst;
765{
766	struct gif_softc *sc = ifp->if_softc;
767	struct gif_softc *sc2;
768	struct sockaddr *osrc, *odst, *sa;
769	int s;
770	int error = 0;
771
772	s = splnet();
773
774	mtx_lock(&gif_mtx);
775	LIST_FOREACH(sc2, &gif_softc_list, gif_list) {
776		if (sc2 == sc)
777			continue;
778		if (!sc2->gif_pdst || !sc2->gif_psrc)
779			continue;
780		if (sc2->gif_pdst->sa_family != dst->sa_family ||
781		    sc2->gif_pdst->sa_len != dst->sa_len ||
782		    sc2->gif_psrc->sa_family != src->sa_family ||
783		    sc2->gif_psrc->sa_len != src->sa_len)
784			continue;
785
786		/*
787		 * Disallow parallel tunnels unless instructed
788		 * otherwise.
789		 */
790		if (!parallel_tunnels &&
791		    bcmp(sc2->gif_pdst, dst, dst->sa_len) == 0 &&
792		    bcmp(sc2->gif_psrc, src, src->sa_len) == 0) {
793			error = EADDRNOTAVAIL;
794			mtx_unlock(&gif_mtx);
795			goto bad;
796		}
797
798		/* XXX both end must be valid? (I mean, not 0.0.0.0) */
799	}
800	mtx_unlock(&gif_mtx);
801
802	/* XXX we can detach from both, but be polite just in case */
803	if (sc->gif_psrc)
804		switch (sc->gif_psrc->sa_family) {
805#ifdef INET
806		case AF_INET:
807			(void)in_gif_detach(sc);
808			break;
809#endif
810#ifdef INET6
811		case AF_INET6:
812			(void)in6_gif_detach(sc);
813			break;
814#endif
815		}
816
817	osrc = sc->gif_psrc;
818	sa = (struct sockaddr *)malloc(src->sa_len, M_IFADDR, M_WAITOK);
819	bcopy((caddr_t)src, (caddr_t)sa, src->sa_len);
820	sc->gif_psrc = sa;
821
822	odst = sc->gif_pdst;
823	sa = (struct sockaddr *)malloc(dst->sa_len, M_IFADDR, M_WAITOK);
824	bcopy((caddr_t)dst, (caddr_t)sa, dst->sa_len);
825	sc->gif_pdst = sa;
826
827	switch (sc->gif_psrc->sa_family) {
828#ifdef INET
829	case AF_INET:
830		error = in_gif_attach(sc);
831		break;
832#endif
833#ifdef INET6
834	case AF_INET6:
835		error = in6_gif_attach(sc);
836		break;
837#endif
838	}
839	if (error) {
840		/* rollback */
841		free((caddr_t)sc->gif_psrc, M_IFADDR);
842		free((caddr_t)sc->gif_pdst, M_IFADDR);
843		sc->gif_psrc = osrc;
844		sc->gif_pdst = odst;
845		goto bad;
846	}
847
848	if (osrc)
849		free((caddr_t)osrc, M_IFADDR);
850	if (odst)
851		free((caddr_t)odst, M_IFADDR);
852
853	if (sc->gif_psrc && sc->gif_pdst)
854		ifp->if_flags |= IFF_RUNNING;
855	else
856		ifp->if_flags &= ~IFF_RUNNING;
857	splx(s);
858
859	return 0;
860
861 bad:
862	if (sc->gif_psrc && sc->gif_pdst)
863		ifp->if_flags |= IFF_RUNNING;
864	else
865		ifp->if_flags &= ~IFF_RUNNING;
866	splx(s);
867
868	return error;
869}
870
871void
872gif_delete_tunnel(ifp)
873	struct ifnet *ifp;
874{
875	struct gif_softc *sc = ifp->if_softc;
876	int s;
877
878	s = splnet();
879
880	if (sc->gif_psrc) {
881		free((caddr_t)sc->gif_psrc, M_IFADDR);
882		sc->gif_psrc = NULL;
883	}
884	if (sc->gif_pdst) {
885		free((caddr_t)sc->gif_pdst, M_IFADDR);
886		sc->gif_pdst = NULL;
887	}
888	/* it is safe to detach from both */
889#ifdef INET
890	(void)in_gif_detach(sc);
891#endif
892#ifdef INET6
893	(void)in6_gif_detach(sc);
894#endif
895
896	if (sc->gif_psrc && sc->gif_pdst)
897		ifp->if_flags |= IFF_RUNNING;
898	else
899		ifp->if_flags &= ~IFF_RUNNING;
900	splx(s);
901}
902