xref: /netbsd-src/sys/net/if_gif.c (revision fb5eed702691094bd687fbf1ded189c87457cd35)
1 /*	$NetBSD: if_gif.c,v 1.156 2021/10/11 05:13:11 knakahara Exp $	*/
2 /*	$KAME: if_gif.c,v 1.76 2001/08/20 02:01:02 kjc 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 <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: if_gif.c,v 1.156 2021/10/11 05:13:11 knakahara Exp $");
35 
36 #ifdef _KERNEL_OPT
37 #include "opt_inet.h"
38 #include "opt_net_mpsafe.h"
39 #endif
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/atomic.h>
44 #include <sys/kernel.h>
45 #include <sys/mbuf.h>
46 #include <sys/socket.h>
47 #include <sys/sockio.h>
48 #include <sys/errno.h>
49 #include <sys/ioctl.h>
50 #include <sys/time.h>
51 #include <sys/socketvar.h>
52 #include <sys/syslog.h>
53 #include <sys/proc.h>
54 #include <sys/cpu.h>
55 #include <sys/intr.h>
56 #include <sys/kmem.h>
57 #include <sys/sysctl.h>
58 #include <sys/xcall.h>
59 #include <sys/device.h>
60 #include <sys/module.h>
61 #include <sys/mutex.h>
62 #include <sys/pserialize.h>
63 #include <sys/psref.h>
64 
65 #include <net/if.h>
66 #include <net/if_types.h>
67 #include <net/netisr.h>
68 #include <net/route.h>
69 #include <net/bpf.h>
70 
71 #include <netinet/in.h>
72 #include <netinet/in_systm.h>
73 #include <netinet/ip.h>
74 #ifdef	INET
75 #include <netinet/in_var.h>
76 #endif	/* INET */
77 #include <netinet/in_gif.h>
78 
79 #ifdef INET6
80 #ifndef INET
81 #include <netinet/in.h>
82 #endif
83 #include <netinet6/in6_var.h>
84 #include <netinet/ip6.h>
85 #include <netinet6/ip6_var.h>
86 #include <netinet6/in6_gif.h>
87 #endif /* INET6 */
88 
89 #include <netinet/ip_encap.h>
90 #include <net/if_gif.h>
91 
92 #include "ioconf.h"
93 
94 #ifdef NET_MPSAFE
95 #define GIF_MPSAFE	1
96 #endif
97 
98 /*
99  * gif global variable definitions
100  */
101 static struct {
102 	LIST_HEAD(gif_sclist, gif_softc) list;
103 	kmutex_t lock;
104 } gif_softcs __cacheline_aligned;
105 
106 struct psref_class *gv_psref_class __read_mostly;
107 
108 static pktq_rps_hash_func_t gif_pktq_rps_hash_p;
109 
110 static int	gifattach0(struct gif_softc *);
111 static int	gif_output(struct ifnet *, struct mbuf *,
112 			   const struct sockaddr *, const struct rtentry *);
113 static void	gif_start(struct ifnet *);
114 static int	gif_transmit(struct ifnet *, struct mbuf *);
115 static int	gif_transmit_direct(struct gif_variant *, struct mbuf *);
116 static int	gif_ioctl(struct ifnet *, u_long, void *);
117 static int	gif_set_tunnel(struct ifnet *, struct sockaddr *,
118 			       struct sockaddr *);
119 static void	gif_delete_tunnel(struct ifnet *);
120 
121 static int	gif_clone_create(struct if_clone *, int);
122 static int	gif_clone_destroy(struct ifnet *);
123 static int	gif_check_nesting(struct ifnet *, struct mbuf *);
124 
125 static int	gif_encap_attach(struct gif_variant *);
126 static int	gif_encap_detach(struct gif_variant *);
127 
128 static void	gif_update_variant(struct gif_softc *, struct gif_variant *);
129 
130 static struct if_clone gif_cloner =
131     IF_CLONE_INITIALIZER("gif", gif_clone_create, gif_clone_destroy);
132 
133 #ifndef MAX_GIF_NEST
134 /*
135  * This macro controls the upper limitation on nesting of gif tunnels.
136  * Since, setting a large value to this macro with a careless configuration
137  * may introduce system crash, we don't allow any nestings by default.
138  * If you need to configure nested gif tunnels, you can define this macro
139  * in your kernel configuration file.  However, if you do so, please be
140  * careful to configure the tunnels so that it won't make a loop.
141  */
142 #define MAX_GIF_NEST 1
143 #endif
144 static int max_gif_nesting = MAX_GIF_NEST;
145 
146 static struct sysctllog *gif_sysctl;
147 
148 #ifdef INET6
149 static int
150 sysctl_gif_pmtu_global(SYSCTLFN_ARGS)
151 {
152 	int error, pmtu;
153 	struct sysctlnode node = *rnode;
154 
155 	pmtu = ip6_gif_pmtu;
156 	node.sysctl_data = &pmtu;
157 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
158 	if (error || newp == NULL)
159 		return error;
160 
161 	switch (pmtu) {
162 	case GIF_PMTU_MINMTU:
163 	case GIF_PMTU_OUTERMTU:
164 		ip6_gif_pmtu = pmtu;
165 		break;
166 	default:
167 		return EINVAL;
168 	}
169 
170 	return 0;
171 }
172 
173 static int
174 sysctl_gif_pmtu_perif(SYSCTLFN_ARGS)
175 {
176 	int error, pmtu;
177 	struct sysctlnode node = *rnode;
178 	struct gif_softc *sc = (struct gif_softc *)node.sysctl_data;
179 
180 	pmtu = sc->gif_pmtu;
181 	node.sysctl_data = &pmtu;
182 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
183 	if (error || newp == NULL)
184 		return error;
185 
186 	switch (pmtu) {
187 	case GIF_PMTU_SYSDEFAULT:
188 	case GIF_PMTU_MINMTU:
189 	case GIF_PMTU_OUTERMTU:
190 		sc->gif_pmtu = pmtu;
191 		break;
192 	default:
193 		return EINVAL;
194 	}
195 
196 	return 0;
197 }
198 #endif
199 
200 static void
201 gif_sysctl_setup(void)
202 {
203 	const struct sysctlnode *node = NULL;
204 
205 	gif_sysctl = NULL;
206 
207 #ifdef INET
208 	/*
209 	 * Previously create "net.inet.ip" entry to avoid sysctl_createv error.
210 	 */
211 	sysctl_createv(NULL, 0, NULL, NULL,
212 		       CTLFLAG_PERMANENT,
213 		       CTLTYPE_NODE, "inet",
214 		       SYSCTL_DESCR("PF_INET related settings"),
215 		       NULL, 0, NULL, 0,
216 		       CTL_NET, PF_INET, CTL_EOL);
217 	sysctl_createv(NULL, 0, NULL, NULL,
218 		       CTLFLAG_PERMANENT,
219 		       CTLTYPE_NODE, "ip",
220 		       SYSCTL_DESCR("IPv4 related settings"),
221 		       NULL, 0, NULL, 0,
222 		       CTL_NET, PF_INET, IPPROTO_IP, CTL_EOL);
223 
224 	sysctl_createv(&gif_sysctl, 0, NULL, NULL,
225 		       CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
226 		       CTLTYPE_INT, "gifttl",
227 		       SYSCTL_DESCR("Default TTL for a gif tunnel datagram"),
228 		       NULL, 0, &ip_gif_ttl, 0,
229 		       CTL_NET, PF_INET, IPPROTO_IP,
230 		       IPCTL_GIF_TTL, CTL_EOL);
231 #endif
232 #ifdef INET6
233 	/*
234 	 * Previously create "net.inet6.ip6" entry to avoid sysctl_createv error.
235 	 */
236 	sysctl_createv(NULL, 0, NULL, NULL,
237 		       CTLFLAG_PERMANENT,
238 		       CTLTYPE_NODE, "inet6",
239 		       SYSCTL_DESCR("PF_INET6 related settings"),
240 		       NULL, 0, NULL, 0,
241 		       CTL_NET, PF_INET6, CTL_EOL);
242 	sysctl_createv(NULL, 0, NULL, NULL,
243 		       CTLFLAG_PERMANENT,
244 		       CTLTYPE_NODE, "ip6",
245 		       SYSCTL_DESCR("IPv6 related settings"),
246 		       NULL, 0, NULL, 0,
247 		       CTL_NET, PF_INET6, IPPROTO_IPV6, CTL_EOL);
248 
249 	sysctl_createv(&gif_sysctl, 0, NULL, NULL,
250 		       CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
251 		       CTLTYPE_INT, "gifhlim",
252 		       SYSCTL_DESCR("Default hop limit for a gif tunnel datagram"),
253 		       NULL, 0, &ip6_gif_hlim, 0,
254 		       CTL_NET, PF_INET6, IPPROTO_IPV6,
255 		       IPV6CTL_GIF_HLIM, CTL_EOL);
256 
257 	sysctl_createv(&gif_sysctl, 0, NULL, NULL,
258 		       CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
259 		       CTLTYPE_INT, "gifpmtu",
260 		       SYSCTL_DESCR("Default Path MTU setting for gif tunnels"),
261 		       sysctl_gif_pmtu_global, 0, NULL, 0,
262 		       CTL_NET, PF_INET6, IPPROTO_IPV6,
263 		       IPV6CTL_GIF_PMTU, CTL_EOL);
264 #endif
265 
266 	sysctl_createv(&gif_sysctl, 0, NULL, &node,
267 		       CTLFLAG_PERMANENT,
268 		       CTLTYPE_NODE, "gif",
269 		       SYSCTL_DESCR("gif global control"),
270 		       NULL, 0, NULL, 0,
271 		       CTL_NET, CTL_CREATE, CTL_EOL);
272 
273 	sysctl_createv(&gif_sysctl, 0, &node, NULL,
274 		       CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
275 		       CTLTYPE_STRING, "rps_hash",
276 		       SYSCTL_DESCR("Interface rps hash function control"),
277 		       sysctl_pktq_rps_hash_handler, 0, (void *)&gif_pktq_rps_hash_p,
278 		       PKTQ_RPS_HASH_NAME_LEN,
279 		       CTL_CREATE, CTL_EOL);
280 }
281 
282 static void
283 gif_perif_sysctl_setup(struct sysctllog **clog, struct gif_softc *sc)
284 {
285 #ifdef INET6
286 	const struct sysctlnode *cnode, *rnode;
287 	struct ifnet *ifp = &sc->gif_if;
288 	const char *ifname = ifp->if_xname;
289 	int rv;
290 
291 	/*
292 	 * Already created in sysctl_sndq_setup().
293 	 */
294 	sysctl_createv(clog, 0, NULL, &rnode,
295 		       CTLFLAG_PERMANENT,
296 		       CTLTYPE_NODE, "interfaces",
297 		       SYSCTL_DESCR("Per-interface controls"),
298 		       NULL, 0, NULL, 0,
299 		       CTL_NET, CTL_CREATE, CTL_EOL);
300 	sysctl_createv(clog, 0, &rnode, &rnode,
301 		       CTLFLAG_PERMANENT,
302 		       CTLTYPE_NODE, ifname,
303 		       SYSCTL_DESCR("Interface controls"),
304 		       NULL, 0, NULL, 0,
305 		       CTL_CREATE, CTL_EOL);
306 
307 	rv = sysctl_createv(clog, 0, &rnode, &cnode,
308 			    CTLFLAG_PERMANENT,
309 			    CTLTYPE_INT, "pmtu",
310 			    SYSCTL_DESCR("Path MTU setting for this gif tunnel"),
311 			    sysctl_gif_pmtu_perif, 0, (void *)sc, 0,
312 			    CTL_CREATE, CTL_EOL);
313 	if (rv != 0)
314 		log(LOG_WARNING, "%s: could not attach sysctl node pmtu\n", ifname);
315 
316 	sc->gif_pmtu = GIF_PMTU_SYSDEFAULT;
317 #endif
318 }
319 
320 /* ARGSUSED */
321 void
322 gifattach(int count)
323 {
324 	/*
325 	 * Nothing to do here, initialization is handled by the
326 	 * module initialization code in gifinit() below).
327 	 */
328 }
329 
330 static void
331 gifinit(void)
332 {
333 
334 	mutex_init(&gif_softcs.lock, MUTEX_DEFAULT, IPL_NONE);
335 	LIST_INIT(&gif_softcs.list);
336 	if_clone_attach(&gif_cloner);
337 
338 	gv_psref_class = psref_class_create("gifvar", IPL_SOFTNET);
339 
340 	gif_pktq_rps_hash_p = pktq_rps_hash_default;
341 	gif_sysctl_setup();
342 }
343 
344 static int
345 gifdetach(void)
346 {
347 
348 	mutex_enter(&gif_softcs.lock);
349 	if (!LIST_EMPTY(&gif_softcs.list)) {
350 		mutex_exit(&gif_softcs.lock);
351 		return EBUSY;
352 	}
353 
354 	psref_class_destroy(gv_psref_class);
355 
356 	if_clone_detach(&gif_cloner);
357 	sysctl_teardown(&gif_sysctl);
358 	mutex_exit(&gif_softcs.lock);
359 	mutex_destroy(&gif_softcs.lock);
360 	return 0;
361 }
362 
363 static int
364 gif_clone_create(struct if_clone *ifc, int unit)
365 {
366 	struct gif_softc *sc;
367 	struct gif_variant *var;
368 	struct ifnet *ifp;
369 	int rv;
370 
371 	sc = kmem_zalloc(sizeof(struct gif_softc), KM_SLEEP);
372 
373 	if_initname(&sc->gif_if, ifc->ifc_name, unit);
374 
375 	rv = gifattach0(sc);
376 	if (rv != 0) {
377 		kmem_free(sc, sizeof(struct gif_softc));
378 		return rv;
379 	}
380 
381 	ifp = &sc->gif_if;
382 	gif_perif_sysctl_setup(&ifp->if_sysctl_log, sc);
383 
384 	var = kmem_zalloc(sizeof(*var), KM_SLEEP);
385 	var->gv_softc = sc;
386 	psref_target_init(&var->gv_psref, gv_psref_class);
387 
388 	sc->gif_var = var;
389 	mutex_init(&sc->gif_lock, MUTEX_DEFAULT, IPL_NONE);
390 	sc->gif_psz = pserialize_create();
391 
392 	sc->gif_ro_percpu = if_tunnel_alloc_ro_percpu();
393 	mutex_enter(&gif_softcs.lock);
394 	LIST_INSERT_HEAD(&gif_softcs.list, sc, gif_list);
395 	mutex_exit(&gif_softcs.lock);
396 	return 0;
397 }
398 
399 static int
400 gifattach0(struct gif_softc *sc)
401 {
402 
403 	sc->gif_if.if_addrlen = 0;
404 	sc->gif_if.if_mtu    = GIF_MTU;
405 	sc->gif_if.if_flags  = IFF_POINTOPOINT | IFF_MULTICAST;
406 #ifdef GIF_MPSAFE
407 	sc->gif_if.if_extflags  |= IFEF_MPSAFE;
408 #endif
409 	sc->gif_if.if_ioctl  = gif_ioctl;
410 	sc->gif_if.if_output = gif_output;
411 	sc->gif_if.if_start = gif_start;
412 	sc->gif_if.if_transmit = gif_transmit;
413 	sc->gif_if.if_type   = IFT_GIF;
414 	sc->gif_if.if_dlt    = DLT_NULL;
415 	sc->gif_if.if_softc  = sc;
416 	IFQ_SET_READY(&sc->gif_if.if_snd);
417 	if_initialize(&sc->gif_if);
418 
419 	sc->gif_if.if_link_state = LINK_STATE_DOWN;
420 	if_alloc_sadl(&sc->gif_if);
421 	bpf_attach(&sc->gif_if, DLT_NULL, sizeof(u_int));
422 	if_register(&sc->gif_if);
423 	return 0;
424 }
425 
426 static int
427 gif_clone_destroy(struct ifnet *ifp)
428 {
429 	struct gif_softc *sc = (void *) ifp;
430 	struct gif_variant *var;
431 
432 	LIST_REMOVE(sc, gif_list);
433 
434 	gif_delete_tunnel(&sc->gif_if);
435 	bpf_detach(ifp);
436 	if_detach(ifp);
437 
438 	if_tunnel_free_ro_percpu(sc->gif_ro_percpu);
439 
440 	pserialize_destroy(sc->gif_psz);
441 	mutex_destroy(&sc->gif_lock);
442 
443 	var = sc->gif_var;
444 	kmem_free(var, sizeof(*var));
445 	kmem_free(sc, sizeof(struct gif_softc));
446 
447 	return 0;
448 }
449 
450 #ifdef GIF_ENCAPCHECK
451 int
452 gif_encapcheck(struct mbuf *m, int off, int proto, void *arg)
453 {
454 	struct ip ip;
455 	struct gif_softc *sc;
456 	struct gif_variant *var;
457 	struct psref psref;
458 	int ret = 0;
459 
460 	sc = arg;
461 	if (sc == NULL)
462 		return 0;
463 
464 	if ((sc->gif_if.if_flags & IFF_UP) == 0)
465 		return 0;
466 
467 	var = gif_getref_variant(sc, &psref);
468 	/* no physical address */
469 	if (var->gv_psrc == NULL || var->gv_pdst == NULL)
470 		goto out;
471 
472 	switch (proto) {
473 #ifdef INET
474 	case IPPROTO_IPV4:
475 		break;
476 #endif
477 #ifdef INET6
478 	case IPPROTO_IPV6:
479 		break;
480 #endif
481 	default:
482 		goto out;
483 	}
484 
485 	/* Bail on short packets */
486 	KASSERT(m->m_flags & M_PKTHDR);
487 	if (m->m_pkthdr.len < sizeof(ip))
488 		goto  out;
489 
490 	m_copydata(m, 0, sizeof(ip), &ip);
491 
492 	switch (ip.ip_v) {
493 #ifdef INET
494 	case 4:
495 		if (var->gv_psrc->sa_family != AF_INET ||
496 		    var->gv_pdst->sa_family != AF_INET)
497 			goto out;
498 		ret = gif_encapcheck4(m, off, proto, var);
499 		break;
500 #endif
501 #ifdef INET6
502 	case 6:
503 		if (m->m_pkthdr.len < sizeof(struct ip6_hdr))
504 			goto out;
505 		if (var->gv_psrc->sa_family != AF_INET6 ||
506 		    var->gv_pdst->sa_family != AF_INET6)
507 			goto out;
508 		ret = gif_encapcheck6(m, off, proto, var);
509 		break;
510 #endif
511 	default:
512 		goto out;
513 	}
514 
515 out:
516 	gif_putref_variant(var, &psref);
517 	return ret;
518 }
519 #endif
520 
521 /*
522  * gif may cause infinite recursion calls when misconfigured.
523  * We'll prevent this by introducing upper limit.
524  */
525 static int
526 gif_check_nesting(struct ifnet *ifp, struct mbuf *m)
527 {
528 
529 	return if_tunnel_check_nesting(ifp, m, max_gif_nesting);
530 }
531 
532 static int
533 gif_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
534     const struct rtentry *rt)
535 {
536 	struct gif_softc *sc = ifp->if_softc;
537 	struct gif_variant *var = NULL;
538 	struct psref psref;
539 	int error = 0;
540 
541 	IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family);
542 
543 	if ((error = gif_check_nesting(ifp, m)) != 0) {
544 		m_freem(m);
545 		goto end;
546 	}
547 
548 	if ((ifp->if_flags & IFF_UP) == 0) {
549 		m_freem(m);
550 		error = ENETDOWN;
551 		goto end;
552 	}
553 
554 	var = gif_getref_variant(sc, &psref);
555 	if (var->gv_psrc == NULL || var->gv_pdst == NULL) {
556 		m_freem(m);
557 		error = ENETDOWN;
558 		goto end;
559 	}
560 	/* XXX should we check if our outer source is legal? */
561 
562 	m->m_flags &= ~(M_BCAST | M_MCAST);
563 
564 	/* use DLT_NULL encapsulation here to pass inner af type */
565 	M_PREPEND(m, sizeof(int), M_DONTWAIT);
566 	if (!m) {
567 		error = ENOBUFS;
568 		goto end;
569 	}
570 	*mtod(m, int *) = dst->sa_family;
571 
572 	/* Clear checksum-offload flags. */
573 	m->m_pkthdr.csum_flags = 0;
574 	m->m_pkthdr.csum_data = 0;
575 
576 	error = if_transmit_lock(ifp, m);
577 
578 end:
579 	if (var != NULL)
580 		gif_putref_variant(var, &psref);
581 	if (error)
582 		if_statinc(ifp, if_oerrors);
583 	return error;
584 }
585 
586 static void
587 gif_start(struct ifnet *ifp)
588 {
589 	struct gif_softc *sc;
590 	struct gif_variant *var;
591 	struct mbuf *m;
592 	struct psref psref;
593 	int family;
594 	int len;
595 	int error;
596 
597 	sc = ifp->if_softc;
598 	var = gif_getref_variant(sc, &psref);
599 
600 	KASSERT(var->gv_output != NULL);
601 
602 	/* output processing */
603 	while (1) {
604 		IFQ_DEQUEUE(&sc->gif_if.if_snd, m);
605 		if (m == NULL)
606 			break;
607 
608 		/* grab and chop off inner af type */
609 		if (sizeof(int) > m->m_len) {
610 			m = m_pullup(m, sizeof(int));
611 			if (!m) {
612 				if_statinc(ifp, if_oerrors);
613 				continue;
614 			}
615 		}
616 		family = *mtod(m, int *);
617 		bpf_mtap(ifp, m, BPF_D_OUT);
618 		m_adj(m, sizeof(int));
619 
620 		len = m->m_pkthdr.len;
621 
622 		error = var->gv_output(var, family, m);
623 		if (error)
624 			if_statinc(ifp, if_oerrors);
625 		else
626 			if_statadd2(ifp, if_opackets, 1, if_obytes, len);
627 	}
628 
629 	gif_putref_variant(var, &psref);
630 }
631 
632 static int
633 gif_transmit(struct ifnet *ifp, struct mbuf *m)
634 {
635 	struct gif_softc *sc;
636 	struct gif_variant *var;
637 	struct psref psref;
638 	int error;
639 
640 	sc = ifp->if_softc;
641 
642 	/* output processing */
643 	if (m == NULL)
644 		return EINVAL;
645 
646 	var = gif_getref_variant(sc, &psref);
647 	error = gif_transmit_direct(var, m);
648 	gif_putref_variant(var, &psref);
649 
650 	return error;
651 }
652 
653 static int
654 gif_transmit_direct(struct gif_variant *var, struct mbuf *m)
655 {
656 	struct ifnet *ifp = &var->gv_softc->gif_if;
657 	int error;
658 	int family;
659 	int len;
660 
661 	KASSERT(gif_heldref_variant(var));
662 	KASSERT(var->gv_output != NULL);
663 
664 	/* grab and chop off inner af type */
665 	if (sizeof(int) > m->m_len) {
666 		m = m_pullup(m, sizeof(int));
667 		if (!m) {
668 			if_statinc(ifp, if_oerrors);
669 			return ENOBUFS;
670 		}
671 	}
672 	family = *mtod(m, int *);
673 	bpf_mtap(ifp, m, BPF_D_OUT);
674 	m_adj(m, sizeof(int));
675 
676 	len = m->m_pkthdr.len;
677 
678 	error = var->gv_output(var, family, m);
679 	if (error)
680 		if_statinc(ifp, if_oerrors);
681 	else
682 		if_statadd2(ifp, if_opackets, 1, if_obytes, len);
683 
684 	return error;
685 }
686 
687 void
688 gif_input(struct mbuf *m, int af, struct ifnet *ifp)
689 {
690 	pktqueue_t *pktq;
691 	size_t pktlen;
692 
693 	if (ifp == NULL) {
694 		/* just in case */
695 		m_freem(m);
696 		return;
697 	}
698 
699 	m_set_rcvif(m, ifp);
700 	pktlen = m->m_pkthdr.len;
701 
702 	bpf_mtap_af(ifp, af, m, BPF_D_IN);
703 
704 	/*
705 	 * Put the packet to the network layer input queue according to the
706 	 * specified address family.  Note: we avoid direct call to the
707 	 * input function of the network layer in order to avoid recursion.
708 	 * This may be revisited in the future.
709 	 */
710 	switch (af) {
711 #ifdef INET
712 	case AF_INET:
713 		pktq = ip_pktq;
714 		break;
715 #endif
716 #ifdef INET6
717 	case AF_INET6:
718 		pktq = ip6_pktq;
719 		break;
720 #endif
721 	default:
722 		m_freem(m);
723 		return;
724 	}
725 
726 	const uint32_t h = pktq_rps_hash(&gif_pktq_rps_hash_p, m);
727 	if (__predict_true(pktq_enqueue(pktq, m, h))) {
728 		if_statadd2(ifp, if_ibytes, pktlen, if_ipackets, 1);
729 	} else {
730 		m_freem(m);
731 	}
732 }
733 
734 /* XXX how should we handle IPv6 scope on SIOC[GS]IFPHYADDR? */
735 static int
736 gif_ioctl(struct ifnet *ifp, u_long cmd, void *data)
737 {
738 	struct gif_softc *sc  = ifp->if_softc;
739 	struct ifreq     *ifr = (struct ifreq*)data;
740 	struct ifaddr    *ifa = (struct ifaddr*)data;
741 	int error = 0, size, bound;
742 	struct sockaddr *dst, *src;
743 	struct gif_variant *var;
744 	struct psref psref;
745 
746 	switch (cmd) {
747 	case SIOCINITIFADDR:
748 		ifp->if_flags |= IFF_UP;
749 		ifa->ifa_rtrequest = p2p_rtrequest;
750 		break;
751 
752 	case SIOCADDMULTI:
753 	case SIOCDELMULTI:
754 		switch (ifr->ifr_addr.sa_family) {
755 #ifdef INET
756 		case AF_INET:	/* IP supports Multicast */
757 			break;
758 #endif /* INET */
759 #ifdef INET6
760 		case AF_INET6:	/* IP6 supports Multicast */
761 			break;
762 #endif /* INET6 */
763 		default:  /* Other protocols doesn't support Multicast */
764 			error = EAFNOSUPPORT;
765 			break;
766 		}
767 		break;
768 
769 	case SIOCSIFMTU:
770 		if (ifr->ifr_mtu < GIF_MTU_MIN || ifr->ifr_mtu > GIF_MTU_MAX)
771 			return EINVAL;
772 		else if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET)
773 			error = 0;
774 		break;
775 
776 #ifdef INET
777 	case SIOCSIFPHYADDR:
778 #endif
779 #ifdef INET6
780 	case SIOCSIFPHYADDR_IN6:
781 #endif /* INET6 */
782 	case SIOCSLIFPHYADDR:
783 		switch (cmd) {
784 #ifdef INET
785 		case SIOCSIFPHYADDR:
786 			src = (struct sockaddr *)
787 				&(((struct in_aliasreq *)data)->ifra_addr);
788 			dst = (struct sockaddr *)
789 				&(((struct in_aliasreq *)data)->ifra_dstaddr);
790 			break;
791 #endif
792 #ifdef INET6
793 		case SIOCSIFPHYADDR_IN6:
794 			src = (struct sockaddr *)
795 				&(((struct in6_aliasreq *)data)->ifra_addr);
796 			dst = (struct sockaddr *)
797 				&(((struct in6_aliasreq *)data)->ifra_dstaddr);
798 			break;
799 #endif
800 		case SIOCSLIFPHYADDR:
801 			src = (struct sockaddr *)
802 				&(((struct if_laddrreq *)data)->addr);
803 			dst = (struct sockaddr *)
804 				&(((struct if_laddrreq *)data)->dstaddr);
805 			break;
806 		default:
807 			return EINVAL;
808 		}
809 
810 		/* sa_family must be equal */
811 		if (src->sa_family != dst->sa_family)
812 			return EINVAL;
813 
814 		/* validate sa_len */
815 		switch (src->sa_family) {
816 #ifdef INET
817 		case AF_INET:
818 			if (src->sa_len != sizeof(struct sockaddr_in))
819 				return EINVAL;
820 			break;
821 #endif
822 #ifdef INET6
823 		case AF_INET6:
824 			if (src->sa_len != sizeof(struct sockaddr_in6))
825 				return EINVAL;
826 			break;
827 #endif
828 		default:
829 			return EAFNOSUPPORT;
830 		}
831 		switch (dst->sa_family) {
832 #ifdef INET
833 		case AF_INET:
834 			if (dst->sa_len != sizeof(struct sockaddr_in))
835 				return EINVAL;
836 			break;
837 #endif
838 #ifdef INET6
839 		case AF_INET6:
840 			if (dst->sa_len != sizeof(struct sockaddr_in6))
841 				return EINVAL;
842 			break;
843 #endif
844 		default:
845 			return EAFNOSUPPORT;
846 		}
847 
848 		/* check sa_family looks sane for the cmd */
849 		switch (cmd) {
850 		case SIOCSIFPHYADDR:
851 			if (src->sa_family == AF_INET)
852 				break;
853 			return EAFNOSUPPORT;
854 #ifdef INET6
855 		case SIOCSIFPHYADDR_IN6:
856 			if (src->sa_family == AF_INET6)
857 				break;
858 			return EAFNOSUPPORT;
859 #endif /* INET6 */
860 		case SIOCSLIFPHYADDR:
861 			/* checks done in the above */
862 			break;
863 		}
864 
865 		/*
866 		 * calls gif_getref_variant() for other softcs to check
867 		 * address pair duplicattion
868 		 */
869 		bound = curlwp_bind();
870 		error = gif_set_tunnel(&sc->gif_if, src, dst);
871 		if (error == 0)
872 			if_link_state_change(&sc->gif_if, LINK_STATE_UP);
873 		curlwp_bindx(bound);
874 
875 		break;
876 
877 #ifdef SIOCDIFPHYADDR
878 	case SIOCDIFPHYADDR:
879 		bound = curlwp_bind();
880 		gif_delete_tunnel(&sc->gif_if);
881 		if_link_state_change(&sc->gif_if, LINK_STATE_DOWN);
882 		curlwp_bindx(bound);
883 		break;
884 #endif
885 
886 	case SIOCGIFPSRCADDR:
887 #ifdef INET6
888 	case SIOCGIFPSRCADDR_IN6:
889 #endif /* INET6 */
890 		bound = curlwp_bind();
891 		var = gif_getref_variant(sc, &psref);
892 		if (var->gv_psrc == NULL) {
893 			gif_putref_variant(var, &psref);
894 			curlwp_bindx(bound);
895 			error = EADDRNOTAVAIL;
896 			goto bad;
897 		}
898 		src = var->gv_psrc;
899 		switch (cmd) {
900 #ifdef INET
901 		case SIOCGIFPSRCADDR:
902 			dst = &ifr->ifr_addr;
903 			size = sizeof(ifr->ifr_addr);
904 			break;
905 #endif /* INET */
906 #ifdef INET6
907 		case SIOCGIFPSRCADDR_IN6:
908 			dst = (struct sockaddr *)
909 				&(((struct in6_ifreq *)data)->ifr_addr);
910 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
911 			break;
912 #endif /* INET6 */
913 		default:
914 			gif_putref_variant(var, &psref);
915 			curlwp_bindx(bound);
916 			error = EADDRNOTAVAIL;
917 			goto bad;
918 		}
919 		if (src->sa_len > size) {
920 			gif_putref_variant(var, &psref);
921 			curlwp_bindx(bound);
922 			return EINVAL;
923 		}
924 		memcpy(dst, src, src->sa_len);
925 		gif_putref_variant(var, &psref);
926 		curlwp_bindx(bound);
927 		break;
928 
929 	case SIOCGIFPDSTADDR:
930 #ifdef INET6
931 	case SIOCGIFPDSTADDR_IN6:
932 #endif /* INET6 */
933 		bound = curlwp_bind();
934 		var = gif_getref_variant(sc, &psref);
935 		if (var->gv_pdst == NULL) {
936 			gif_putref_variant(var, &psref);
937 			curlwp_bindx(bound);
938 			error = EADDRNOTAVAIL;
939 			goto bad;
940 		}
941 		src = var->gv_pdst;
942 		switch (cmd) {
943 #ifdef INET
944 		case SIOCGIFPDSTADDR:
945 			dst = &ifr->ifr_addr;
946 			size = sizeof(ifr->ifr_addr);
947 			break;
948 #endif /* INET */
949 #ifdef INET6
950 		case SIOCGIFPDSTADDR_IN6:
951 			dst = (struct sockaddr *)
952 				&(((struct in6_ifreq *)data)->ifr_addr);
953 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
954 			break;
955 #endif /* INET6 */
956 		default:
957 			gif_putref_variant(var, &psref);
958 			curlwp_bindx(bound);
959 			error = EADDRNOTAVAIL;
960 			goto bad;
961 		}
962 		if (src->sa_len > size) {
963 			gif_putref_variant(var, &psref);
964 			curlwp_bindx(bound);
965 			return EINVAL;
966 		}
967 		memcpy(dst, src, src->sa_len);
968 		gif_putref_variant(var, &psref);
969 		curlwp_bindx(bound);
970 		break;
971 
972 	case SIOCGLIFPHYADDR:
973 		bound = curlwp_bind();
974 		var = gif_getref_variant(sc, &psref);
975 		if (var->gv_psrc == NULL || var->gv_pdst == NULL) {
976 			gif_putref_variant(var, &psref);
977 			curlwp_bindx(bound);
978 			error = EADDRNOTAVAIL;
979 			goto bad;
980 		}
981 
982 		/* copy src */
983 		src = var->gv_psrc;
984 		dst = (struct sockaddr *)
985 			&(((struct if_laddrreq *)data)->addr);
986 		size = sizeof(((struct if_laddrreq *)data)->addr);
987 		if (src->sa_len > size) {
988 			gif_putref_variant(var, &psref);
989 			curlwp_bindx(bound);
990 			return EINVAL;
991 		}
992 		memcpy(dst, src, src->sa_len);
993 
994 		/* copy dst */
995 		src = var->gv_pdst;
996 		dst = (struct sockaddr *)
997 			&(((struct if_laddrreq *)data)->dstaddr);
998 		size = sizeof(((struct if_laddrreq *)data)->dstaddr);
999 		if (src->sa_len > size) {
1000 			gif_putref_variant(var, &psref);
1001 			curlwp_bindx(bound);
1002 			return EINVAL;
1003 		}
1004 		memcpy(dst, src, src->sa_len);
1005 		gif_putref_variant(var, &psref);
1006 		curlwp_bindx(bound);
1007 		break;
1008 
1009 	default:
1010 		return ifioctl_common(ifp, cmd, data);
1011 	}
1012  bad:
1013 	return error;
1014 }
1015 
1016 static int
1017 gif_encap_attach(struct gif_variant *var)
1018 {
1019 	int error;
1020 
1021 	if (var == NULL || var->gv_psrc == NULL)
1022 		return EINVAL;
1023 
1024 	switch (var->gv_psrc->sa_family) {
1025 #ifdef INET
1026 	case AF_INET:
1027 		error = in_gif_attach(var);
1028 		break;
1029 #endif
1030 #ifdef INET6
1031 	case AF_INET6:
1032 		error = in6_gif_attach(var);
1033 		break;
1034 #endif
1035 	default:
1036 		error = EINVAL;
1037 		break;
1038 	}
1039 
1040 	return error;
1041 }
1042 
1043 static int
1044 gif_encap_detach(struct gif_variant *var)
1045 {
1046 	int error;
1047 
1048 	if (var == NULL || var->gv_psrc == NULL)
1049 		return EINVAL;
1050 
1051 	switch (var->gv_psrc->sa_family) {
1052 #ifdef INET
1053 	case AF_INET:
1054 		error = in_gif_detach(var);
1055 		break;
1056 #endif
1057 #ifdef INET6
1058 	case AF_INET6:
1059 		error = in6_gif_detach(var);
1060 		break;
1061 #endif
1062 	default:
1063 		error = EINVAL;
1064 		break;
1065 	}
1066 
1067 	return error;
1068 }
1069 
1070 static int
1071 gif_set_tunnel(struct ifnet *ifp, struct sockaddr *src, struct sockaddr *dst)
1072 {
1073 	struct gif_softc *sc = ifp->if_softc;
1074 	struct gif_softc *sc2;
1075 	struct gif_variant *ovar, *nvar;
1076 	struct sockaddr *osrc, *odst;
1077 	struct sockaddr *nsrc, *ndst;
1078 	int error;
1079 #ifndef GIF_MPSAFE
1080 	int s;
1081 
1082 	s = splsoftnet();
1083 #endif
1084 	error = encap_lock_enter();
1085 	if (error) {
1086 #ifndef GIF_MPSAFE
1087 		splx(s);
1088 #endif
1089 		return error;
1090 	}
1091 
1092 	nsrc = sockaddr_dup(src, M_WAITOK);
1093 	ndst = sockaddr_dup(dst, M_WAITOK);
1094 	nvar = kmem_alloc(sizeof(*nvar), KM_SLEEP);
1095 
1096 	mutex_enter(&sc->gif_lock);
1097 
1098 	ovar = sc->gif_var;
1099 
1100 	if ((ovar->gv_pdst && sockaddr_cmp(ovar->gv_pdst, dst) == 0) &&
1101 	    (ovar->gv_psrc && sockaddr_cmp(ovar->gv_psrc, src) == 0)) {
1102 		/* address and port pair not changed. */
1103 		error = 0;
1104 		goto out;
1105 	}
1106 
1107 	mutex_enter(&gif_softcs.lock);
1108 	LIST_FOREACH(sc2, &gif_softcs.list, gif_list) {
1109 		struct gif_variant *var2;
1110 		struct psref psref;
1111 
1112 		if (sc2 == sc)
1113 			continue;
1114 		var2 = gif_getref_variant(sc2, &psref);
1115 		if (!var2->gv_pdst || !var2->gv_psrc) {
1116 			gif_putref_variant(var2, &psref);
1117 			continue;
1118 		}
1119 		/* can't configure same pair of address onto two gifs */
1120 		if (sockaddr_cmp(var2->gv_pdst, dst) == 0 &&
1121 		    sockaddr_cmp(var2->gv_psrc, src) == 0) {
1122 			/* continue to use the old configuration. */
1123 			gif_putref_variant(var2, &psref);
1124 			mutex_exit(&gif_softcs.lock);
1125 			error =  EADDRNOTAVAIL;
1126 			goto out;
1127 		}
1128 		gif_putref_variant(var2, &psref);
1129 		/* XXX both end must be valid? (I mean, not 0.0.0.0) */
1130 	}
1131 	mutex_exit(&gif_softcs.lock);
1132 
1133 	osrc = ovar->gv_psrc;
1134 	odst = ovar->gv_pdst;
1135 
1136 	*nvar = *ovar;
1137 	nvar->gv_psrc = nsrc;
1138 	nvar->gv_pdst = ndst;
1139 	nvar->gv_encap_cookie4 = NULL;
1140 	nvar->gv_encap_cookie6 = NULL;
1141 	error = gif_encap_attach(nvar);
1142 	if (error)
1143 		goto out;
1144 	psref_target_init(&nvar->gv_psref, gv_psref_class);
1145 	gif_update_variant(sc, nvar);
1146 
1147 	mutex_exit(&sc->gif_lock);
1148 
1149 	(void)gif_encap_detach(ovar);
1150 	encap_lock_exit();
1151 
1152 	if (osrc)
1153 		sockaddr_free(osrc);
1154 	if (odst)
1155 		sockaddr_free(odst);
1156 	kmem_free(ovar, sizeof(*ovar));
1157 
1158 #ifndef GIF_MPSAFE
1159 	splx(s);
1160 #endif
1161 	return 0;
1162 
1163  out:
1164 	sockaddr_free(nsrc);
1165 	sockaddr_free(ndst);
1166 	kmem_free(nvar, sizeof(*nvar));
1167 
1168 	mutex_exit(&sc->gif_lock);
1169 	encap_lock_exit();
1170 #ifndef GIF_MPSAFE
1171 	splx(s);
1172 #endif
1173 	return error;
1174 }
1175 
1176 static void
1177 gif_delete_tunnel(struct ifnet *ifp)
1178 {
1179 	struct gif_softc *sc = ifp->if_softc;
1180 	struct gif_variant *ovar, *nvar;
1181 	struct sockaddr *osrc, *odst;
1182 	int error;
1183 #ifndef GIF_MPSAFE
1184 	int s;
1185 
1186 	s = splsoftnet();
1187 #endif
1188 	error = encap_lock_enter();
1189 	if (error) {
1190 #ifndef GIF_MPSAFE
1191 		splx(s);
1192 #endif
1193 		return;
1194 	}
1195 
1196 	nvar = kmem_alloc(sizeof(*nvar), KM_SLEEP);
1197 
1198 	mutex_enter(&sc->gif_lock);
1199 
1200 	ovar = sc->gif_var;
1201 	osrc = ovar->gv_psrc;
1202 	odst = ovar->gv_pdst;
1203 	if (osrc == NULL || odst == NULL) {
1204 		/* address pair not changed. */
1205 		mutex_exit(&sc->gif_lock);
1206 		encap_lock_exit();
1207 		kmem_free(nvar, sizeof(*nvar));
1208 #ifndef GIF_MPSAFE
1209 		splx(s);
1210 #endif
1211 		return;
1212 	}
1213 
1214 	*nvar = *ovar;
1215 	nvar->gv_psrc = NULL;
1216 	nvar->gv_pdst = NULL;
1217 	nvar->gv_encap_cookie4 = NULL;
1218 	nvar->gv_encap_cookie6 = NULL;
1219 	nvar->gv_output = NULL;
1220 	psref_target_init(&nvar->gv_psref, gv_psref_class);
1221 	gif_update_variant(sc, nvar);
1222 
1223 	mutex_exit(&sc->gif_lock);
1224 
1225 	gif_encap_detach(ovar);
1226 	encap_lock_exit();
1227 
1228 	sockaddr_free(osrc);
1229 	sockaddr_free(odst);
1230 	kmem_free(ovar, sizeof(*ovar));
1231 
1232 #ifndef GIF_MPSAFE
1233 	splx(s);
1234 #endif
1235 }
1236 
1237 /*
1238  * gif_variant update API.
1239  *
1240  * Assumption:
1241  * reader side dereferences sc->gif_var in reader critical section only,
1242  * that is, all of reader sides do not reader the sc->gif_var after
1243  * pserialize_perform().
1244  */
1245 static void
1246 gif_update_variant(struct gif_softc *sc, struct gif_variant *nvar)
1247 {
1248 	struct ifnet *ifp = &sc->gif_if;
1249 	struct gif_variant *ovar = sc->gif_var;
1250 
1251 	KASSERT(mutex_owned(&sc->gif_lock));
1252 
1253 	atomic_store_release(&sc->gif_var, nvar);
1254 	pserialize_perform(sc->gif_psz);
1255 	psref_target_destroy(&ovar->gv_psref, gv_psref_class);
1256 
1257 	if (nvar->gv_psrc != NULL && nvar->gv_pdst != NULL)
1258 		ifp->if_flags |= IFF_RUNNING;
1259 	else
1260 		ifp->if_flags &= ~IFF_RUNNING;
1261 }
1262 
1263 /*
1264  * Module infrastructure
1265  */
1266 #include "if_module.h"
1267 
1268 IF_MODULE(MODULE_CLASS_DRIVER, gif, "ip_ecn")
1269