xref: /freebsd/sys/net/if_gif.c (revision 5861f9665471e98e544f6fa3ce73c4912229ff82)
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 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/kernel.h>
39 #include <sys/malloc.h>
40 #include <sys/mbuf.h>
41 #include <sys/module.h>
42 #include <sys/socket.h>
43 #include <sys/sockio.h>
44 #include <sys/errno.h>
45 #include <sys/time.h>
46 #include <sys/sysctl.h>
47 #include <sys/syslog.h>
48 #include <sys/priv.h>
49 #include <sys/proc.h>
50 #include <sys/protosw.h>
51 #include <sys/conf.h>
52 #include <sys/vimage.h>
53 #include <machine/cpu.h>
54 
55 #include <net/if.h>
56 #include <net/if_clone.h>
57 #include <net/if_types.h>
58 #include <net/netisr.h>
59 #include <net/route.h>
60 #include <net/bpf.h>
61 
62 #include <netinet/in.h>
63 #include <netinet/in_systm.h>
64 #include <netinet/ip.h>
65 #ifdef	INET
66 #include <netinet/in_var.h>
67 #include <netinet/in_gif.h>
68 #include <netinet/ip_var.h>
69 #endif	/* INET */
70 
71 #ifdef INET6
72 #ifndef INET
73 #include <netinet/in.h>
74 #endif
75 #include <netinet6/in6_var.h>
76 #include <netinet/ip6.h>
77 #include <netinet6/ip6_var.h>
78 #include <netinet6/scope6_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 <net/ethernet.h>
85 #include <net/if_bridgevar.h>
86 #include <net/if_gif.h>
87 
88 #include <security/mac/mac_framework.h>
89 
90 #define GIFNAME		"gif"
91 
92 /*
93  * gif_mtx protects the global gif_softc_list.
94  */
95 static struct mtx gif_mtx;
96 static MALLOC_DEFINE(M_GIF, "gif", "Generic Tunnel Interface");
97 
98 #ifndef VIMAGE
99 #ifndef VIMAGE_GLOBALS
100 struct vnet_gif vnet_gif_0;
101 #endif
102 #endif
103 
104 #ifdef VIMAGE_GLOBALS
105 static LIST_HEAD(, gif_softc) gif_softc_list;
106 static int max_gif_nesting;
107 static int parallel_tunnels;
108 #ifdef INET
109 int ip_gif_ttl;
110 #endif
111 #ifdef INET6
112 int ip6_gif_hlim;
113 #endif
114 #endif
115 
116 void	(*ng_gif_input_p)(struct ifnet *ifp, struct mbuf **mp, int af);
117 void	(*ng_gif_input_orphan_p)(struct ifnet *ifp, struct mbuf *m, int af);
118 void	(*ng_gif_attach_p)(struct ifnet *ifp);
119 void	(*ng_gif_detach_p)(struct ifnet *ifp);
120 
121 static void	gif_start(struct ifnet *);
122 static int	gif_clone_create(struct if_clone *, int, caddr_t);
123 static void	gif_clone_destroy(struct ifnet *);
124 static int	vnet_gif_iattach(const void *);
125 
126 #ifndef VIMAGE_GLOBALS
127 static const vnet_modinfo_t vnet_gif_modinfo = {
128 	.vmi_id		= VNET_MOD_GIF,
129 	.vmi_name	= "gif",
130 	.vmi_size	= sizeof(struct vnet_gif),
131 	.vmi_dependson	= VNET_MOD_NET,
132 	.vmi_iattach	= vnet_gif_iattach
133 };
134 #endif
135 
136 IFC_SIMPLE_DECLARE(gif, 0);
137 
138 static int gifmodevent(module_t, int, void *);
139 
140 SYSCTL_DECL(_net_link);
141 SYSCTL_NODE(_net_link, IFT_GIF, gif, CTLFLAG_RW, 0,
142     "Generic Tunnel Interface");
143 #ifndef MAX_GIF_NEST
144 /*
145  * This macro controls the default upper limitation on nesting of gif tunnels.
146  * Since, setting a large value to this macro with a careless configuration
147  * may introduce system crash, we don't allow any nestings by default.
148  * If you need to configure nested gif tunnels, you can define this macro
149  * in your kernel configuration file.  However, if you do so, please be
150  * careful to configure the tunnels so that it won't make a loop.
151  */
152 #define MAX_GIF_NEST 1
153 #endif
154 SYSCTL_V_INT(V_NET, vnet_gif, _net_link_gif, OID_AUTO, max_nesting,
155     CTLFLAG_RW, max_gif_nesting, 0, "Max nested tunnels");
156 
157 #ifdef INET6
158 SYSCTL_DECL(_net_inet6_ip6);
159 SYSCTL_V_INT(V_NET, vnet_gif, _net_inet6_ip6, IPV6CTL_GIF_HLIM,
160     gifhlim, CTLFLAG_RW, ip6_gif_hlim, 0, "");
161 #endif
162 
163 /*
164  * By default, we disallow creation of multiple tunnels between the same
165  * pair of addresses.  Some applications require this functionality so
166  * we allow control over this check here.
167  */
168 SYSCTL_V_INT(V_NET, vnet_gif, _net_link_gif, OID_AUTO, parallel_tunnels,
169     CTLFLAG_RW, parallel_tunnels, 0, "Allow parallel tunnels?");
170 
171 /* copy from src/sys/net/if_ethersubr.c */
172 static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] =
173 			{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
174 #ifndef ETHER_IS_BROADCAST
175 #define ETHER_IS_BROADCAST(addr) \
176 	(bcmp(etherbroadcastaddr, (addr), ETHER_ADDR_LEN) == 0)
177 #endif
178 
179 static int
180 gif_clone_create(ifc, unit, params)
181 	struct if_clone *ifc;
182 	int unit;
183 	caddr_t params;
184 {
185 	INIT_VNET_GIF(curvnet);
186 	struct gif_softc *sc;
187 
188 	sc = malloc(sizeof(struct gif_softc), M_GIF, M_WAITOK | M_ZERO);
189 	sc->gif_fibnum = curthread->td_proc->p_fibnum;
190 	GIF2IFP(sc) = if_alloc(IFT_GIF);
191 	if (GIF2IFP(sc) == NULL) {
192 		free(sc, M_GIF);
193 		return (ENOSPC);
194 	}
195 
196 	GIF_LOCK_INIT(sc);
197 
198 	GIF2IFP(sc)->if_softc = sc;
199 	if_initname(GIF2IFP(sc), ifc->ifc_name, unit);
200 
201 	sc->encap_cookie4 = sc->encap_cookie6 = NULL;
202 	sc->gif_options = GIF_ACCEPT_REVETHIP;
203 
204 	GIF2IFP(sc)->if_addrlen = 0;
205 	GIF2IFP(sc)->if_mtu    = GIF_MTU;
206 	GIF2IFP(sc)->if_flags  = IFF_POINTOPOINT | IFF_MULTICAST;
207 #if 0
208 	/* turn off ingress filter */
209 	GIF2IFP(sc)->if_flags  |= IFF_LINK2;
210 #endif
211 	GIF2IFP(sc)->if_ioctl  = gif_ioctl;
212 	GIF2IFP(sc)->if_start  = gif_start;
213 	GIF2IFP(sc)->if_output = gif_output;
214 	GIF2IFP(sc)->if_snd.ifq_maxlen = IFQ_MAXLEN;
215 	if_attach(GIF2IFP(sc));
216 	bpfattach(GIF2IFP(sc), DLT_NULL, sizeof(u_int32_t));
217 	if (ng_gif_attach_p != NULL)
218 		(*ng_gif_attach_p)(GIF2IFP(sc));
219 
220 	mtx_lock(&gif_mtx);
221 	LIST_INSERT_HEAD(&V_gif_softc_list, sc, gif_list);
222 	mtx_unlock(&gif_mtx);
223 
224 	return (0);
225 }
226 
227 static void
228 gif_clone_destroy(ifp)
229 	struct ifnet *ifp;
230 {
231 #if defined(INET) || defined(INET6)
232 	int err;
233 #endif
234 	struct gif_softc *sc = ifp->if_softc;
235 
236 	mtx_lock(&gif_mtx);
237 	LIST_REMOVE(sc, gif_list);
238 	mtx_unlock(&gif_mtx);
239 
240 	gif_delete_tunnel(ifp);
241 #ifdef INET6
242 	if (sc->encap_cookie6 != NULL) {
243 		err = encap_detach(sc->encap_cookie6);
244 		KASSERT(err == 0, ("Unexpected error detaching encap_cookie6"));
245 	}
246 #endif
247 #ifdef INET
248 	if (sc->encap_cookie4 != NULL) {
249 		err = encap_detach(sc->encap_cookie4);
250 		KASSERT(err == 0, ("Unexpected error detaching encap_cookie4"));
251 	}
252 #endif
253 
254 	if (ng_gif_detach_p != NULL)
255 		(*ng_gif_detach_p)(ifp);
256 	bpfdetach(ifp);
257 	if_detach(ifp);
258 	if_free(ifp);
259 
260 	GIF_LOCK_DESTROY(sc);
261 
262 	free(sc, M_GIF);
263 }
264 
265 static int
266 vnet_gif_iattach(const void *unused __unused)
267 {
268 	INIT_VNET_GIF(curvnet);
269 
270 	LIST_INIT(&V_gif_softc_list);
271 	V_max_gif_nesting = MAX_GIF_NEST;
272 #ifdef XBONEHACK
273 	V_parallel_tunnels = 1;
274 #else
275 	V_parallel_tunnels = 0;
276 #endif
277 #ifdef INET
278 	V_ip_gif_ttl = GIF_TTL;
279 #endif
280 #ifdef INET6
281 	V_ip6_gif_hlim = GIF_HLIM;
282 #endif
283 
284 	return (0);
285 }
286 
287 static int
288 gifmodevent(mod, type, data)
289 	module_t mod;
290 	int type;
291 	void *data;
292 {
293 
294 	switch (type) {
295 	case MOD_LOAD:
296 		mtx_init(&gif_mtx, "gif_mtx", NULL, MTX_DEF);
297 
298 #ifndef VIMAGE_GLOBALS
299 		vnet_mod_register(&vnet_gif_modinfo);
300 #else
301 		vnet_gif_iattach(NULL);
302 #endif
303 		if_clone_attach(&gif_cloner);
304 
305 		break;
306 	case MOD_UNLOAD:
307 		if_clone_detach(&gif_cloner);
308 #ifdef VIMAGE
309 		vnet_mod_deregister(&vnet_gif_modinfo);
310 #endif
311 		mtx_destroy(&gif_mtx);
312 		break;
313 	default:
314 		return EOPNOTSUPP;
315 	}
316 	return 0;
317 }
318 
319 static moduledata_t gif_mod = {
320 	"if_gif",
321 	gifmodevent,
322 	0
323 };
324 
325 DECLARE_MODULE(if_gif, gif_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
326 MODULE_VERSION(if_gif, 1);
327 
328 int
329 gif_encapcheck(m, off, proto, arg)
330 	const struct mbuf *m;
331 	int off;
332 	int proto;
333 	void *arg;
334 {
335 	struct ip ip;
336 	struct gif_softc *sc;
337 
338 	sc = (struct gif_softc *)arg;
339 	if (sc == NULL)
340 		return 0;
341 
342 	if ((GIF2IFP(sc)->if_flags & IFF_UP) == 0)
343 		return 0;
344 
345 	/* no physical address */
346 	if (!sc->gif_psrc || !sc->gif_pdst)
347 		return 0;
348 
349 	switch (proto) {
350 #ifdef INET
351 	case IPPROTO_IPV4:
352 		break;
353 #endif
354 #ifdef INET6
355 	case IPPROTO_IPV6:
356 		break;
357 #endif
358 	case IPPROTO_ETHERIP:
359 		break;
360 
361 	default:
362 		return 0;
363 	}
364 
365 	/* Bail on short packets */
366 	if (m->m_pkthdr.len < sizeof(ip))
367 		return 0;
368 
369 	m_copydata(m, 0, sizeof(ip), (caddr_t)&ip);
370 
371 	switch (ip.ip_v) {
372 #ifdef INET
373 	case 4:
374 		if (sc->gif_psrc->sa_family != AF_INET ||
375 		    sc->gif_pdst->sa_family != AF_INET)
376 			return 0;
377 		return gif_encapcheck4(m, off, proto, arg);
378 #endif
379 #ifdef INET6
380 	case 6:
381 		if (m->m_pkthdr.len < sizeof(struct ip6_hdr))
382 			return 0;
383 		if (sc->gif_psrc->sa_family != AF_INET6 ||
384 		    sc->gif_pdst->sa_family != AF_INET6)
385 			return 0;
386 		return gif_encapcheck6(m, off, proto, arg);
387 #endif
388 	default:
389 		return 0;
390 	}
391 }
392 
393 static void
394 gif_start(struct ifnet *ifp)
395 {
396 	struct gif_softc *sc;
397 	struct mbuf *m;
398 
399 	sc = ifp->if_softc;
400 
401 	ifp->if_drv_flags |= IFF_DRV_OACTIVE;
402 	for (;;) {
403 		IFQ_DEQUEUE(&ifp->if_snd, m);
404 		if (m == 0)
405 			break;
406 
407 		gif_output(ifp, m, sc->gif_pdst, NULL);
408 
409 	}
410 	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
411 
412 	return;
413 }
414 
415 int
416 gif_output(ifp, m, dst, ro)
417 	struct ifnet *ifp;
418 	struct mbuf *m;
419 	struct sockaddr *dst;
420 	struct route *ro;
421 {
422 	INIT_VNET_GIF(ifp->if_vnet);
423 	struct gif_softc *sc = ifp->if_softc;
424 	struct m_tag *mtag;
425 	int error = 0;
426 	int gif_called;
427 	u_int32_t af;
428 
429 #ifdef MAC
430 	error = mac_ifnet_check_transmit(ifp, m);
431 	if (error) {
432 		m_freem(m);
433 		goto end;
434 	}
435 #endif
436 
437 	/*
438 	 * gif may cause infinite recursion calls when misconfigured.
439 	 * We'll prevent this by detecting loops.
440 	 *
441 	 * High nesting level may cause stack exhaustion.
442 	 * We'll prevent this by introducing upper limit.
443 	 */
444 	gif_called = 1;
445 	mtag = m_tag_locate(m, MTAG_GIF, MTAG_GIF_CALLED, NULL);
446 	while (mtag != NULL) {
447 		if (*(struct ifnet **)(mtag + 1) == ifp) {
448 			log(LOG_NOTICE,
449 			    "gif_output: loop detected on %s\n",
450 			    (*(struct ifnet **)(mtag + 1))->if_xname);
451 			m_freem(m);
452 			error = EIO;	/* is there better errno? */
453 			goto end;
454 		}
455 		mtag = m_tag_locate(m, MTAG_GIF, MTAG_GIF_CALLED, mtag);
456 		gif_called++;
457 	}
458 	if (gif_called > V_max_gif_nesting) {
459 		log(LOG_NOTICE,
460 		    "gif_output: recursively called too many times(%d)\n",
461 		    gif_called);
462 		m_freem(m);
463 		error = EIO;	/* is there better errno? */
464 		goto end;
465 	}
466 	mtag = m_tag_alloc(MTAG_GIF, MTAG_GIF_CALLED, sizeof(struct ifnet *),
467 	    M_NOWAIT);
468 	if (mtag == NULL) {
469 		m_freem(m);
470 		error = ENOMEM;
471 		goto end;
472 	}
473 	*(struct ifnet **)(mtag + 1) = ifp;
474 	m_tag_prepend(m, mtag);
475 
476 	m->m_flags &= ~(M_BCAST|M_MCAST);
477 
478 	GIF_LOCK(sc);
479 
480 	if (!(ifp->if_flags & IFF_UP) ||
481 	    sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
482 		GIF_UNLOCK(sc);
483 		m_freem(m);
484 		error = ENETDOWN;
485 		goto end;
486 	}
487 
488 	/* BPF writes need to be handled specially. */
489 	if (dst->sa_family == AF_UNSPEC) {
490 		bcopy(dst->sa_data, &af, sizeof(af));
491 		dst->sa_family = af;
492 	}
493 
494 	af = dst->sa_family;
495 	BPF_MTAP2(ifp, &af, sizeof(af), m);
496 	ifp->if_opackets++;
497 	ifp->if_obytes += m->m_pkthdr.len;
498 
499 	/* override to IPPROTO_ETHERIP for bridged traffic */
500 	if (ifp->if_bridge)
501 		af = AF_LINK;
502 
503 	M_SETFIB(m, sc->gif_fibnum);
504 	/* inner AF-specific encapsulation */
505 
506 	/* XXX should we check if our outer source is legal? */
507 
508 	/* dispatch to output logic based on outer AF */
509 	switch (sc->gif_psrc->sa_family) {
510 #ifdef INET
511 	case AF_INET:
512 		error = in_gif_output(ifp, af, m);
513 		break;
514 #endif
515 #ifdef INET6
516 	case AF_INET6:
517 		error = in6_gif_output(ifp, af, m);
518 		break;
519 #endif
520 	default:
521 		m_freem(m);
522 		error = ENETDOWN;
523 	}
524 
525 	GIF_UNLOCK(sc);
526   end:
527 	if (error)
528 		ifp->if_oerrors++;
529 	return (error);
530 }
531 
532 void
533 gif_input(m, af, ifp)
534 	struct mbuf *m;
535 	int af;
536 	struct ifnet *ifp;
537 {
538 	int isr, n;
539 	struct gif_softc *sc = ifp->if_softc;
540 	struct etherip_header *eip;
541 	struct ether_header *eh;
542 	struct ifnet *oldifp;
543 
544 	if (ifp == NULL) {
545 		/* just in case */
546 		m_freem(m);
547 		return;
548 	}
549 
550 	m->m_pkthdr.rcvif = ifp;
551 
552 #ifdef MAC
553 	mac_ifnet_create_mbuf(ifp, m);
554 #endif
555 
556 	if (bpf_peers_present(ifp->if_bpf)) {
557 		u_int32_t af1 = af;
558 		bpf_mtap2(ifp->if_bpf, &af1, sizeof(af1), m);
559 	}
560 
561 	if (ng_gif_input_p != NULL) {
562 		(*ng_gif_input_p)(ifp, &m, af);
563 		if (m == NULL)
564 			return;
565 	}
566 
567 	/*
568 	 * Put the packet to the network layer input queue according to the
569 	 * specified address family.
570 	 * Note: older versions of gif_input directly called network layer
571 	 * input functions, e.g. ip6_input, here.  We changed the policy to
572 	 * prevent too many recursive calls of such input functions, which
573 	 * might cause kernel panic.  But the change may introduce another
574 	 * problem; if the input queue is full, packets are discarded.
575 	 * The kernel stack overflow really happened, and we believed
576 	 * queue-full rarely occurs, so we changed the policy.
577 	 */
578 	switch (af) {
579 #ifdef INET
580 	case AF_INET:
581 		isr = NETISR_IP;
582 		break;
583 #endif
584 #ifdef INET6
585 	case AF_INET6:
586 		isr = NETISR_IPV6;
587 		break;
588 #endif
589 	case AF_LINK:
590 		n = sizeof(struct etherip_header) + sizeof(struct ether_header);
591 		if (n > m->m_len) {
592 			m = m_pullup(m, n);
593 			if (m == NULL) {
594 				ifp->if_ierrors++;
595 				return;
596 			}
597 		}
598 
599 		eip = mtod(m, struct etherip_header *);
600 		/*
601 		 * GIF_ACCEPT_REVETHIP (enabled by default) intentionally
602 		 * accepts an EtherIP packet with revered version field in
603 		 * the header.  This is a knob for backward compatibility
604 		 * with FreeBSD 7.2R or prior.
605 		 */
606 		if (sc->gif_options & GIF_ACCEPT_REVETHIP) {
607 			if (eip->eip_resvl != ETHERIP_VERSION
608 			    && eip->eip_ver != ETHERIP_VERSION) {
609 				/* discard unknown versions */
610 				m_freem(m);
611 				return;
612 			}
613 		} else {
614 			if (eip->eip_ver != ETHERIP_VERSION) {
615 				/* discard unknown versions */
616 				m_freem(m);
617 				return;
618 			}
619 		}
620 		m_adj(m, sizeof(struct etherip_header));
621 
622 		m->m_flags &= ~(M_BCAST|M_MCAST);
623 		m->m_pkthdr.rcvif = ifp;
624 
625 		if (ifp->if_bridge) {
626 			oldifp = ifp;
627 			eh = mtod(m, struct ether_header *);
628 			if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
629 				if (ETHER_IS_BROADCAST(eh->ether_dhost))
630 					m->m_flags |= M_BCAST;
631 				else
632 					m->m_flags |= M_MCAST;
633 				ifp->if_imcasts++;
634 			}
635 			BRIDGE_INPUT(ifp, m);
636 
637 			if (m != NULL && ifp != oldifp) {
638 				/*
639 				 * The bridge gave us back itself or one of the
640 				 * members for which the frame is addressed.
641 				 */
642 				ether_demux(ifp, m);
643 				return;
644 			}
645 		}
646 		if (m != NULL)
647 			m_freem(m);
648 		return;
649 
650 	default:
651 		if (ng_gif_input_orphan_p != NULL)
652 			(*ng_gif_input_orphan_p)(ifp, m, af);
653 		else
654 			m_freem(m);
655 		return;
656 	}
657 
658 	ifp->if_ipackets++;
659 	ifp->if_ibytes += m->m_pkthdr.len;
660 	netisr_dispatch(isr, m);
661 }
662 
663 /* XXX how should we handle IPv6 scope on SIOC[GS]IFPHYADDR? */
664 int
665 gif_ioctl(ifp, cmd, data)
666 	struct ifnet *ifp;
667 	u_long cmd;
668 	caddr_t data;
669 {
670 	struct gif_softc *sc  = ifp->if_softc;
671 	struct ifreq     *ifr = (struct ifreq*)data;
672 	int error = 0, size;
673 	u_int	options;
674 	struct sockaddr *dst, *src;
675 #ifdef	SIOCSIFMTU /* xxx */
676 	u_long mtu;
677 #endif
678 
679 	switch (cmd) {
680 	case SIOCSIFADDR:
681 		ifp->if_flags |= IFF_UP;
682 		break;
683 
684 	case SIOCSIFDSTADDR:
685 		break;
686 
687 	case SIOCADDMULTI:
688 	case SIOCDELMULTI:
689 		break;
690 
691 #ifdef	SIOCSIFMTU /* xxx */
692 	case SIOCGIFMTU:
693 		break;
694 
695 	case SIOCSIFMTU:
696 		mtu = ifr->ifr_mtu;
697 		if (mtu < GIF_MTU_MIN || mtu > GIF_MTU_MAX)
698 			return (EINVAL);
699 		ifp->if_mtu = mtu;
700 		break;
701 #endif /* SIOCSIFMTU */
702 
703 #ifdef INET
704 	case SIOCSIFPHYADDR:
705 #endif
706 #ifdef INET6
707 	case SIOCSIFPHYADDR_IN6:
708 #endif /* INET6 */
709 	case SIOCSLIFPHYADDR:
710 		switch (cmd) {
711 #ifdef INET
712 		case SIOCSIFPHYADDR:
713 			src = (struct sockaddr *)
714 				&(((struct in_aliasreq *)data)->ifra_addr);
715 			dst = (struct sockaddr *)
716 				&(((struct in_aliasreq *)data)->ifra_dstaddr);
717 			break;
718 #endif
719 #ifdef INET6
720 		case SIOCSIFPHYADDR_IN6:
721 			src = (struct sockaddr *)
722 				&(((struct in6_aliasreq *)data)->ifra_addr);
723 			dst = (struct sockaddr *)
724 				&(((struct in6_aliasreq *)data)->ifra_dstaddr);
725 			break;
726 #endif
727 		case SIOCSLIFPHYADDR:
728 			src = (struct sockaddr *)
729 				&(((struct if_laddrreq *)data)->addr);
730 			dst = (struct sockaddr *)
731 				&(((struct if_laddrreq *)data)->dstaddr);
732 			break;
733 		default:
734 			return EINVAL;
735 		}
736 
737 		/* sa_family must be equal */
738 		if (src->sa_family != dst->sa_family)
739 			return EINVAL;
740 
741 		/* validate sa_len */
742 		switch (src->sa_family) {
743 #ifdef INET
744 		case AF_INET:
745 			if (src->sa_len != sizeof(struct sockaddr_in))
746 				return EINVAL;
747 			break;
748 #endif
749 #ifdef INET6
750 		case AF_INET6:
751 			if (src->sa_len != sizeof(struct sockaddr_in6))
752 				return EINVAL;
753 			break;
754 #endif
755 		default:
756 			return EAFNOSUPPORT;
757 		}
758 		switch (dst->sa_family) {
759 #ifdef INET
760 		case AF_INET:
761 			if (dst->sa_len != sizeof(struct sockaddr_in))
762 				return EINVAL;
763 			break;
764 #endif
765 #ifdef INET6
766 		case AF_INET6:
767 			if (dst->sa_len != sizeof(struct sockaddr_in6))
768 				return EINVAL;
769 			break;
770 #endif
771 		default:
772 			return EAFNOSUPPORT;
773 		}
774 
775 		/* check sa_family looks sane for the cmd */
776 		switch (cmd) {
777 		case SIOCSIFPHYADDR:
778 			if (src->sa_family == AF_INET)
779 				break;
780 			return EAFNOSUPPORT;
781 #ifdef INET6
782 		case SIOCSIFPHYADDR_IN6:
783 			if (src->sa_family == AF_INET6)
784 				break;
785 			return EAFNOSUPPORT;
786 #endif /* INET6 */
787 		case SIOCSLIFPHYADDR:
788 			/* checks done in the above */
789 			break;
790 		}
791 
792 		error = gif_set_tunnel(GIF2IFP(sc), src, dst);
793 		break;
794 
795 #ifdef SIOCDIFPHYADDR
796 	case SIOCDIFPHYADDR:
797 		gif_delete_tunnel(GIF2IFP(sc));
798 		break;
799 #endif
800 
801 	case SIOCGIFPSRCADDR:
802 #ifdef INET6
803 	case SIOCGIFPSRCADDR_IN6:
804 #endif /* INET6 */
805 		if (sc->gif_psrc == NULL) {
806 			error = EADDRNOTAVAIL;
807 			goto bad;
808 		}
809 		src = sc->gif_psrc;
810 		switch (cmd) {
811 #ifdef INET
812 		case SIOCGIFPSRCADDR:
813 			dst = &ifr->ifr_addr;
814 			size = sizeof(ifr->ifr_addr);
815 			break;
816 #endif /* INET */
817 #ifdef INET6
818 		case SIOCGIFPSRCADDR_IN6:
819 			dst = (struct sockaddr *)
820 				&(((struct in6_ifreq *)data)->ifr_addr);
821 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
822 			break;
823 #endif /* INET6 */
824 		default:
825 			error = EADDRNOTAVAIL;
826 			goto bad;
827 		}
828 		if (src->sa_len > size)
829 			return EINVAL;
830 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
831 #ifdef INET6
832 		if (dst->sa_family == AF_INET6) {
833 			error = sa6_recoverscope((struct sockaddr_in6 *)dst);
834 			if (error != 0)
835 				return (error);
836 		}
837 #endif
838 		break;
839 
840 	case SIOCGIFPDSTADDR:
841 #ifdef INET6
842 	case SIOCGIFPDSTADDR_IN6:
843 #endif /* INET6 */
844 		if (sc->gif_pdst == NULL) {
845 			error = EADDRNOTAVAIL;
846 			goto bad;
847 		}
848 		src = sc->gif_pdst;
849 		switch (cmd) {
850 #ifdef INET
851 		case SIOCGIFPDSTADDR:
852 			dst = &ifr->ifr_addr;
853 			size = sizeof(ifr->ifr_addr);
854 			break;
855 #endif /* INET */
856 #ifdef INET6
857 		case SIOCGIFPDSTADDR_IN6:
858 			dst = (struct sockaddr *)
859 				&(((struct in6_ifreq *)data)->ifr_addr);
860 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
861 			break;
862 #endif /* INET6 */
863 		default:
864 			error = EADDRNOTAVAIL;
865 			goto bad;
866 		}
867 		if (src->sa_len > size)
868 			return EINVAL;
869 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
870 #ifdef INET6
871 		if (dst->sa_family == AF_INET6) {
872 			error = sa6_recoverscope((struct sockaddr_in6 *)dst);
873 			if (error != 0)
874 				return (error);
875 		}
876 #endif
877 		break;
878 
879 	case SIOCGLIFPHYADDR:
880 		if (sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
881 			error = EADDRNOTAVAIL;
882 			goto bad;
883 		}
884 
885 		/* copy src */
886 		src = sc->gif_psrc;
887 		dst = (struct sockaddr *)
888 			&(((struct if_laddrreq *)data)->addr);
889 		size = sizeof(((struct if_laddrreq *)data)->addr);
890 		if (src->sa_len > size)
891 			return EINVAL;
892 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
893 
894 		/* copy dst */
895 		src = sc->gif_pdst;
896 		dst = (struct sockaddr *)
897 			&(((struct if_laddrreq *)data)->dstaddr);
898 		size = sizeof(((struct if_laddrreq *)data)->dstaddr);
899 		if (src->sa_len > size)
900 			return EINVAL;
901 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
902 		break;
903 
904 	case SIOCSIFFLAGS:
905 		/* if_ioctl() takes care of it */
906 		break;
907 
908 	case GIFGOPTS:
909 		options = sc->gif_options;
910 		error = copyout(&options, ifr->ifr_data,
911 				sizeof(options));
912 		break;
913 
914 	case GIFSOPTS:
915 		if ((error = priv_check(curthread, PRIV_NET_GIF)) != 0)
916 			break;
917 		error = copyin(ifr->ifr_data, &options, sizeof(options));
918 		if (error)
919 			break;
920 		if (options & ~GIF_OPTMASK)
921 			error = EINVAL;
922 		else
923 			sc->gif_options = options;
924 		break;
925 
926 	default:
927 		error = EINVAL;
928 		break;
929 	}
930  bad:
931 	return error;
932 }
933 
934 /*
935  * XXXRW: There's a general event-ordering issue here: the code to check
936  * if a given tunnel is already present happens before we perform a
937  * potentially blocking setup of the tunnel.  This code needs to be
938  * re-ordered so that the check and replacement can be atomic using
939  * a mutex.
940  */
941 int
942 gif_set_tunnel(ifp, src, dst)
943 	struct ifnet *ifp;
944 	struct sockaddr *src;
945 	struct sockaddr *dst;
946 {
947 	INIT_VNET_GIF(ifp->if_vnet);
948 	struct gif_softc *sc = ifp->if_softc;
949 	struct gif_softc *sc2;
950 	struct sockaddr *osrc, *odst, *sa;
951 	int error = 0;
952 
953 	mtx_lock(&gif_mtx);
954 	LIST_FOREACH(sc2, &V_gif_softc_list, gif_list) {
955 		if (sc2 == sc)
956 			continue;
957 		if (!sc2->gif_pdst || !sc2->gif_psrc)
958 			continue;
959 		if (sc2->gif_pdst->sa_family != dst->sa_family ||
960 		    sc2->gif_pdst->sa_len != dst->sa_len ||
961 		    sc2->gif_psrc->sa_family != src->sa_family ||
962 		    sc2->gif_psrc->sa_len != src->sa_len)
963 			continue;
964 
965 		/*
966 		 * Disallow parallel tunnels unless instructed
967 		 * otherwise.
968 		 */
969 		if (!V_parallel_tunnels &&
970 		    bcmp(sc2->gif_pdst, dst, dst->sa_len) == 0 &&
971 		    bcmp(sc2->gif_psrc, src, src->sa_len) == 0) {
972 			error = EADDRNOTAVAIL;
973 			mtx_unlock(&gif_mtx);
974 			goto bad;
975 		}
976 
977 		/* XXX both end must be valid? (I mean, not 0.0.0.0) */
978 	}
979 	mtx_unlock(&gif_mtx);
980 
981 	/* XXX we can detach from both, but be polite just in case */
982 	if (sc->gif_psrc)
983 		switch (sc->gif_psrc->sa_family) {
984 #ifdef INET
985 		case AF_INET:
986 			(void)in_gif_detach(sc);
987 			break;
988 #endif
989 #ifdef INET6
990 		case AF_INET6:
991 			(void)in6_gif_detach(sc);
992 			break;
993 #endif
994 		}
995 
996 	osrc = sc->gif_psrc;
997 	sa = (struct sockaddr *)malloc(src->sa_len, M_IFADDR, M_WAITOK);
998 	bcopy((caddr_t)src, (caddr_t)sa, src->sa_len);
999 	sc->gif_psrc = sa;
1000 
1001 	odst = sc->gif_pdst;
1002 	sa = (struct sockaddr *)malloc(dst->sa_len, M_IFADDR, M_WAITOK);
1003 	bcopy((caddr_t)dst, (caddr_t)sa, dst->sa_len);
1004 	sc->gif_pdst = sa;
1005 
1006 	switch (sc->gif_psrc->sa_family) {
1007 #ifdef INET
1008 	case AF_INET:
1009 		error = in_gif_attach(sc);
1010 		break;
1011 #endif
1012 #ifdef INET6
1013 	case AF_INET6:
1014 		/*
1015 		 * Check validity of the scope zone ID of the addresses, and
1016 		 * convert it into the kernel internal form if necessary.
1017 		 */
1018 		error = sa6_embedscope((struct sockaddr_in6 *)sc->gif_psrc, 0);
1019 		if (error != 0)
1020 			break;
1021 		error = sa6_embedscope((struct sockaddr_in6 *)sc->gif_pdst, 0);
1022 		if (error != 0)
1023 			break;
1024 		error = in6_gif_attach(sc);
1025 		break;
1026 #endif
1027 	}
1028 	if (error) {
1029 		/* rollback */
1030 		free((caddr_t)sc->gif_psrc, M_IFADDR);
1031 		free((caddr_t)sc->gif_pdst, M_IFADDR);
1032 		sc->gif_psrc = osrc;
1033 		sc->gif_pdst = odst;
1034 		goto bad;
1035 	}
1036 
1037 	if (osrc)
1038 		free((caddr_t)osrc, M_IFADDR);
1039 	if (odst)
1040 		free((caddr_t)odst, M_IFADDR);
1041 
1042  bad:
1043 	if (sc->gif_psrc && sc->gif_pdst)
1044 		ifp->if_drv_flags |= IFF_DRV_RUNNING;
1045 	else
1046 		ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
1047 
1048 	return error;
1049 }
1050 
1051 void
1052 gif_delete_tunnel(ifp)
1053 	struct ifnet *ifp;
1054 {
1055 	struct gif_softc *sc = ifp->if_softc;
1056 
1057 	if (sc->gif_psrc) {
1058 		free((caddr_t)sc->gif_psrc, M_IFADDR);
1059 		sc->gif_psrc = NULL;
1060 	}
1061 	if (sc->gif_pdst) {
1062 		free((caddr_t)sc->gif_pdst, M_IFADDR);
1063 		sc->gif_pdst = NULL;
1064 	}
1065 	/* it is safe to detach from both */
1066 #ifdef INET
1067 	(void)in_gif_detach(sc);
1068 #endif
1069 #ifdef INET6
1070 	(void)in6_gif_detach(sc);
1071 #endif
1072 	ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
1073 }
1074