xref: /netbsd-src/sys/net/if_gre.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /*	$NetBSD: if_gre.c,v 1.167 2015/08/24 22:21:26 pooka Exp $ */
2 
3 /*
4  * Copyright (c) 1998, 2008 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Heiko W.Rupp <hwr@pilhuhn.de>
9  *
10  * IPv6-over-GRE contributed by Gert Doering <gert@greenie.muc.de>
11  *
12  * GRE over UDP/IPv4/IPv6 sockets contributed by David Young <dyoung@NetBSD.org>
13  *
14  * Redistribution and use in source and binary forms, with or without
15  * modification, are permitted provided that the following conditions
16  * are met:
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  * 2. Redistributions in binary form must reproduce the above copyright
20  *    notice, this list of conditions and the following disclaimer in the
21  *    documentation and/or other materials provided with the distribution.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
24  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
25  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
26  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
27  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
33  * POSSIBILITY OF SUCH DAMAGE.
34  *
35  * This material is based upon work partially supported by NSF
36  * under Contract No. NSF CNS-0626584.
37  */
38 
39 /*
40  * Encapsulate L3 protocols into IP
41  * See RFC 1701 and 1702 for more details.
42  * If_gre is compatible with Cisco GRE tunnels, so you can
43  * have a NetBSD box as the other end of a tunnel interface of a Cisco
44  * router. See gre(4) for more details.
45  */
46 
47 #include <sys/cdefs.h>
48 __KERNEL_RCSID(0, "$NetBSD: if_gre.c,v 1.167 2015/08/24 22:21:26 pooka Exp $");
49 
50 #ifdef _KERNEL_OPT
51 #include "opt_atalk.h"
52 #include "opt_gre.h"
53 #include "opt_inet.h"
54 #include "opt_mpls.h"
55 #endif
56 
57 #include <sys/param.h>
58 #include <sys/file.h>
59 #include <sys/filedesc.h>
60 #include <sys/malloc.h>
61 #include <sys/mallocvar.h>
62 #include <sys/mbuf.h>
63 #include <sys/proc.h>
64 #include <sys/domain.h>
65 #include <sys/protosw.h>
66 #include <sys/socket.h>
67 #include <sys/socketvar.h>
68 #include <sys/ioctl.h>
69 #include <sys/queue.h>
70 #include <sys/intr.h>
71 #include <sys/systm.h>
72 #include <sys/sysctl.h>
73 #include <sys/kauth.h>
74 
75 #include <sys/kernel.h>
76 #include <sys/mutex.h>
77 #include <sys/condvar.h>
78 #include <sys/kthread.h>
79 
80 #include <sys/cpu.h>
81 
82 #include <net/ethertypes.h>
83 #include <net/if.h>
84 #include <net/if_types.h>
85 #include <net/netisr.h>
86 #include <net/route.h>
87 
88 #include <netinet/in_systm.h>
89 #include <netinet/in.h>
90 #include <netinet/ip.h> /* we always need this for sizeof(struct ip) */
91 
92 #ifdef INET
93 #include <netinet/in_var.h>
94 #include <netinet/ip_var.h>
95 #endif
96 
97 #ifdef INET6
98 #include <netinet6/in6_var.h>
99 #endif
100 
101 #ifdef MPLS
102 #include <netmpls/mpls.h>
103 #include <netmpls/mpls_var.h>
104 #endif
105 
106 #ifdef NETATALK
107 #include <netatalk/at.h>
108 #include <netatalk/at_var.h>
109 #include <netatalk/at_extern.h>
110 #endif
111 
112 #include <sys/time.h>
113 #include <net/bpf.h>
114 
115 #include <net/if_gre.h>
116 
117 #include <compat/sys/socket.h>
118 #include <compat/sys/sockio.h>
119 
120 #include "ioconf.h"
121 
122 /*
123  * It is not easy to calculate the right value for a GRE MTU.
124  * We leave this task to the admin and use the same default that
125  * other vendors use.
126  */
127 #define GREMTU 1476
128 
129 #ifdef GRE_DEBUG
130 int gre_debug = 0;
131 #define	GRE_DPRINTF(__sc, ...)						\
132 	do {								\
133 		if (__predict_false(gre_debug ||			\
134 		    ((__sc)->sc_if.if_flags & IFF_DEBUG) != 0)) {	\
135 			printf("%s.%d: ", __func__, __LINE__);		\
136 			printf(__VA_ARGS__);				\
137 		}							\
138 	} while (/*CONSTCOND*/0)
139 #else
140 #define	GRE_DPRINTF(__sc, __fmt, ...)	do { } while (/*CONSTCOND*/0)
141 #endif /* GRE_DEBUG */
142 
143 int ip_gre_ttl = GRE_TTL;
144 
145 static int gre_clone_create(struct if_clone *, int);
146 static int gre_clone_destroy(struct ifnet *);
147 
148 static struct if_clone gre_cloner =
149     IF_CLONE_INITIALIZER("gre", gre_clone_create, gre_clone_destroy);
150 
151 static int gre_input(struct gre_softc *, struct mbuf *, int,
152     const struct gre_h *);
153 static bool gre_is_nullconf(const struct gre_soparm *);
154 static int gre_output(struct ifnet *, struct mbuf *,
155 			   const struct sockaddr *, struct rtentry *);
156 static int gre_ioctl(struct ifnet *, u_long, void *);
157 static int gre_getsockname(struct socket *, struct sockaddr *);
158 static int gre_getpeername(struct socket *, struct sockaddr *);
159 static int gre_getnames(struct socket *, struct lwp *,
160     struct sockaddr_storage *, struct sockaddr_storage *);
161 static void gre_clearconf(struct gre_soparm *, bool);
162 static int gre_soreceive(struct socket *, struct mbuf **);
163 static int gre_sosend(struct socket *, struct mbuf *);
164 static struct socket *gre_reconf(struct gre_softc *, const struct gre_soparm *);
165 
166 static bool gre_fp_send(struct gre_softc *, enum gre_msg, file_t *);
167 static bool gre_fp_recv(struct gre_softc *);
168 static void gre_fp_recvloop(void *);
169 
170 static void
171 gre_bufq_init(struct gre_bufq *bq, size_t len0)
172 {
173 	memset(bq, 0, sizeof(*bq));
174 	bq->bq_q = pcq_create(len0, KM_SLEEP);
175 	KASSERT(bq->bq_q != NULL);
176 }
177 
178 static struct mbuf *
179 gre_bufq_dequeue(struct gre_bufq *bq)
180 {
181 	return pcq_get(bq->bq_q);
182 }
183 
184 static void
185 gre_bufq_purge(struct gre_bufq *bq)
186 {
187 	struct mbuf *m;
188 
189 	while ((m = gre_bufq_dequeue(bq)) != NULL)
190 		m_freem(m);
191 }
192 
193 static void
194 gre_bufq_destroy(struct gre_bufq *bq)
195 {
196 	gre_bufq_purge(bq);
197 	pcq_destroy(bq->bq_q);
198 }
199 
200 static int
201 gre_bufq_enqueue(struct gre_bufq *bq, struct mbuf *m)
202 {
203 	KASSERT(bq->bq_q != NULL);
204 
205 	if (!pcq_put(bq->bq_q, m)) {
206 		bq->bq_drops++;
207 		return ENOBUFS;
208 	}
209 	return 0;
210 }
211 
212 static void
213 greintr(void *arg)
214 {
215 	struct gre_softc *sc = (struct gre_softc *)arg;
216 	struct socket *so = sc->sc_soparm.sp_so;
217 	int rc;
218 	struct mbuf *m;
219 
220 	KASSERT(so != NULL);
221 
222 	sc->sc_send_ev.ev_count++;
223 	GRE_DPRINTF(sc, "enter\n");
224 	while ((m = gre_bufq_dequeue(&sc->sc_snd)) != NULL) {
225 		/* XXX handle ENOBUFS? */
226 		if ((rc = gre_sosend(so, m)) != 0)
227 			GRE_DPRINTF(sc, "gre_sosend failed %d\n", rc);
228 	}
229 }
230 
231 /* Caller must hold sc->sc_mtx. */
232 static void
233 gre_fp_wait(struct gre_softc *sc)
234 {
235 	sc->sc_fp_waiters++;
236 	cv_wait(&sc->sc_fp_condvar, &sc->sc_mtx);
237 	sc->sc_fp_waiters--;
238 }
239 
240 static void
241 gre_evcnt_detach(struct gre_softc *sc)
242 {
243 	evcnt_detach(&sc->sc_recv_ev);
244 	evcnt_detach(&sc->sc_block_ev);
245 	evcnt_detach(&sc->sc_error_ev);
246 	evcnt_detach(&sc->sc_pullup_ev);
247 	evcnt_detach(&sc->sc_unsupp_ev);
248 
249 	evcnt_detach(&sc->sc_send_ev);
250 	evcnt_detach(&sc->sc_oflow_ev);
251 }
252 
253 static void
254 gre_evcnt_attach(struct gre_softc *sc)
255 {
256 	evcnt_attach_dynamic(&sc->sc_recv_ev, EVCNT_TYPE_MISC,
257 	    NULL, sc->sc_if.if_xname, "recv");
258 	evcnt_attach_dynamic(&sc->sc_block_ev, EVCNT_TYPE_MISC,
259 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "would block");
260 	evcnt_attach_dynamic(&sc->sc_error_ev, EVCNT_TYPE_MISC,
261 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "error");
262 	evcnt_attach_dynamic(&sc->sc_pullup_ev, EVCNT_TYPE_MISC,
263 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "pullup failed");
264 	evcnt_attach_dynamic(&sc->sc_unsupp_ev, EVCNT_TYPE_MISC,
265 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "unsupported");
266 
267 	evcnt_attach_dynamic(&sc->sc_send_ev, EVCNT_TYPE_MISC,
268 	    NULL, sc->sc_if.if_xname, "send");
269 	evcnt_attach_dynamic(&sc->sc_oflow_ev, EVCNT_TYPE_MISC,
270 	    &sc->sc_send_ev, sc->sc_if.if_xname, "overflow");
271 }
272 
273 static int
274 gre_clone_create(struct if_clone *ifc, int unit)
275 {
276 	int rc;
277 	struct gre_softc *sc;
278 	struct gre_soparm *sp;
279 	const struct sockaddr *any;
280 
281 	if ((any = sockaddr_any_by_family(AF_INET)) == NULL &&
282 	    (any = sockaddr_any_by_family(AF_INET6)) == NULL)
283 		goto fail0;
284 
285 	sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK|M_ZERO);
286 	mutex_init(&sc->sc_mtx, MUTEX_DRIVER, IPL_SOFTNET);
287 	cv_init(&sc->sc_condvar, "gre wait");
288 	cv_init(&sc->sc_fp_condvar, "gre fp");
289 
290 	if_initname(&sc->sc_if, ifc->ifc_name, unit);
291 	sc->sc_if.if_softc = sc;
292 	sc->sc_if.if_type = IFT_TUNNEL;
293 	sc->sc_if.if_addrlen = 0;
294 	sc->sc_if.if_hdrlen = sizeof(struct ip) + sizeof(struct gre_h);
295 	sc->sc_if.if_dlt = DLT_NULL;
296 	sc->sc_if.if_mtu = GREMTU;
297 	sc->sc_if.if_flags = IFF_POINTOPOINT|IFF_MULTICAST;
298 	sc->sc_if.if_output = gre_output;
299 	sc->sc_if.if_ioctl = gre_ioctl;
300 	sp = &sc->sc_soparm;
301 	sockaddr_copy(sstosa(&sp->sp_dst), sizeof(sp->sp_dst), any);
302 	sockaddr_copy(sstosa(&sp->sp_src), sizeof(sp->sp_src), any);
303 	sp->sp_proto = IPPROTO_GRE;
304 	sp->sp_type = SOCK_RAW;
305 
306 	sc->sc_fd = -1;
307 
308 	rc = kthread_create(PRI_NONE, KTHREAD_MPSAFE, NULL, gre_fp_recvloop, sc,
309 	    NULL, "%s", sc->sc_if.if_xname);
310 	if (rc)
311 		goto fail1;
312 
313 	gre_evcnt_attach(sc);
314 
315 	gre_bufq_init(&sc->sc_snd, 17);
316 	sc->sc_if.if_flags |= IFF_LINK0;
317 	if_attach(&sc->sc_if);
318 	if_alloc_sadl(&sc->sc_if);
319 	bpf_attach(&sc->sc_if, DLT_NULL, sizeof(uint32_t));
320 	return 0;
321 
322 fail1:	cv_destroy(&sc->sc_fp_condvar);
323 	cv_destroy(&sc->sc_condvar);
324 	mutex_destroy(&sc->sc_mtx);
325 	free(sc, M_DEVBUF);
326 fail0:	return -1;
327 }
328 
329 static int
330 gre_clone_destroy(struct ifnet *ifp)
331 {
332 	int s;
333 	struct gre_softc *sc = ifp->if_softc;
334 
335 	GRE_DPRINTF(sc, "\n");
336 
337 	bpf_detach(ifp);
338 	s = splnet();
339 	if_detach(ifp);
340 
341 	GRE_DPRINTF(sc, "\n");
342 	/* Note that we must not hold the mutex while we call gre_reconf(). */
343 	gre_reconf(sc, NULL);
344 
345 	mutex_enter(&sc->sc_mtx);
346 	sc->sc_msg = GRE_M_STOP;
347 	cv_signal(&sc->sc_fp_condvar);
348 	while (sc->sc_fp_waiters > 0)
349 		cv_wait(&sc->sc_fp_condvar, &sc->sc_mtx);
350 	mutex_exit(&sc->sc_mtx);
351 
352 	splx(s);
353 
354 	cv_destroy(&sc->sc_condvar);
355 	cv_destroy(&sc->sc_fp_condvar);
356 	mutex_destroy(&sc->sc_mtx);
357 	gre_bufq_destroy(&sc->sc_snd);
358 	gre_evcnt_detach(sc);
359 	free(sc, M_DEVBUF);
360 
361 	return 0;
362 }
363 
364 static void
365 gre_receive(struct socket *so, void *arg, int events, int waitflag)
366 {
367 	struct gre_softc *sc = (struct gre_softc *)arg;
368 	int rc;
369 	const struct gre_h *gh;
370 	struct mbuf *m;
371 
372 	GRE_DPRINTF(sc, "enter\n");
373 
374 	sc->sc_recv_ev.ev_count++;
375 
376 	rc = gre_soreceive(so, &m);
377 	/* TBD Back off if ECONNREFUSED (indicates
378 	 * ICMP Port Unreachable)?
379 	 */
380 	if (rc == EWOULDBLOCK) {
381 		GRE_DPRINTF(sc, "EWOULDBLOCK\n");
382 		sc->sc_block_ev.ev_count++;
383 		return;
384 	} else if (rc != 0 || m == NULL) {
385 		GRE_DPRINTF(sc, "%s: rc %d m %p\n",
386 		    sc->sc_if.if_xname, rc, (void *)m);
387 		sc->sc_error_ev.ev_count++;
388 		return;
389 	}
390 	if (m->m_len < sizeof(*gh) && (m = m_pullup(m, sizeof(*gh))) == NULL) {
391 		GRE_DPRINTF(sc, "m_pullup failed\n");
392 		sc->sc_pullup_ev.ev_count++;
393 		return;
394 	}
395 	gh = mtod(m, const struct gre_h *);
396 
397 	if (gre_input(sc, m, 0, gh) == 0) {
398 		sc->sc_unsupp_ev.ev_count++;
399 		GRE_DPRINTF(sc, "dropping unsupported\n");
400 		m_freem(m);
401 	}
402 }
403 
404 static void
405 gre_upcall_add(struct socket *so, void *arg)
406 {
407 	/* XXX What if the kernel already set an upcall? */
408 	KASSERT((so->so_rcv.sb_flags & SB_UPCALL) == 0);
409 	so->so_upcallarg = arg;
410 	so->so_upcall = gre_receive;
411 	so->so_rcv.sb_flags |= SB_UPCALL;
412 }
413 
414 static void
415 gre_upcall_remove(struct socket *so)
416 {
417 	so->so_rcv.sb_flags &= ~SB_UPCALL;
418 	so->so_upcallarg = NULL;
419 	so->so_upcall = NULL;
420 }
421 
422 static int
423 gre_socreate(struct gre_softc *sc, const struct gre_soparm *sp, int *fdout)
424 {
425 	int fd, rc;
426 	struct socket *so;
427 	struct sockaddr_big sbig;
428 	sa_family_t af;
429 	int val;
430 
431 	GRE_DPRINTF(sc, "enter\n");
432 
433 	af = sp->sp_src.ss_family;
434 	rc = fsocreate(af, NULL, sp->sp_type, sp->sp_proto, &fd);
435 	if (rc != 0) {
436 		GRE_DPRINTF(sc, "fsocreate failed\n");
437 		return rc;
438 	}
439 
440 	if ((rc = fd_getsock(fd, &so)) != 0)
441 		return rc;
442 
443 	memcpy(&sbig, &sp->sp_src, sizeof(sp->sp_src));
444 	if ((rc = sobind(so, (struct sockaddr *)&sbig, curlwp)) != 0) {
445 		GRE_DPRINTF(sc, "sobind failed\n");
446 		goto out;
447 	}
448 
449 	memcpy(&sbig, &sp->sp_dst, sizeof(sp->sp_dst));
450 	solock(so);
451 	if ((rc = soconnect(so, (struct sockaddr *)&sbig, curlwp)) != 0) {
452 		GRE_DPRINTF(sc, "soconnect failed\n");
453 		sounlock(so);
454 		goto out;
455 	}
456 	sounlock(so);
457 
458 	/* XXX convert to a (new) SOL_SOCKET call */
459   	KASSERT(so->so_proto != NULL);
460  	rc = so_setsockopt(curlwp, so, IPPROTO_IP, IP_TTL,
461 	    &ip_gre_ttl, sizeof(ip_gre_ttl));
462   	if (rc != 0) {
463  		GRE_DPRINTF(sc, "so_setsockopt ttl failed\n");
464   		rc = 0;
465   	}
466 
467  	val = 1;
468  	rc = so_setsockopt(curlwp, so, SOL_SOCKET, SO_NOHEADER,
469 	    &val, sizeof(val));
470   	if (rc != 0) {
471  		GRE_DPRINTF(sc, "so_setsockopt SO_NOHEADER failed\n");
472 		rc = 0;
473 	}
474 out:
475 	if (rc != 0)
476 		fd_close(fd);
477 	else  {
478 		fd_putfile(fd);
479 		*fdout = fd;
480 	}
481 
482 	return rc;
483 }
484 
485 static int
486 gre_sosend(struct socket *so, struct mbuf *top)
487 {
488 	struct proc	*p;
489 	long		space, resid;
490 	int		error;
491 	struct lwp * const l = curlwp;
492 
493 	p = l->l_proc;
494 
495 	resid = top->m_pkthdr.len;
496 	if (p)
497 		l->l_ru.ru_msgsnd++;
498 #define	snderr(errno)	{ error = errno; goto release; }
499 
500 	solock(so);
501 	if ((error = sblock(&so->so_snd, M_NOWAIT)) != 0)
502 		goto out;
503 	if (so->so_state & SS_CANTSENDMORE)
504 		snderr(EPIPE);
505 	if (so->so_error) {
506 		error = so->so_error;
507 		so->so_error = 0;
508 		goto release;
509 	}
510 	if ((so->so_state & SS_ISCONNECTED) == 0) {
511 		if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
512 			snderr(ENOTCONN);
513 		} else {
514 			snderr(EDESTADDRREQ);
515 		}
516 	}
517 	space = sbspace(&so->so_snd);
518 	if (resid > so->so_snd.sb_hiwat)
519 		snderr(EMSGSIZE);
520 	if (space < resid)
521 		snderr(EWOULDBLOCK);
522 	/*
523 	 * Data is prepackaged in "top".
524 	 */
525 	if (so->so_state & SS_CANTSENDMORE)
526 		snderr(EPIPE);
527 	error = (*so->so_proto->pr_usrreqs->pr_send)(so,
528 	    top, NULL, NULL, l);
529 	top = NULL;
530  release:
531 	sbunlock(&so->so_snd);
532  out:
533  	sounlock(so);
534 	if (top != NULL)
535 		m_freem(top);
536 	return error;
537 }
538 
539 /* This is a stripped-down version of soreceive() that will never
540  * block.  It will support SOCK_DGRAM sockets.  It may also support
541  * SOCK_SEQPACKET sockets.
542  */
543 static int
544 gre_soreceive(struct socket *so, struct mbuf **mp0)
545 {
546 	struct mbuf *m, **mp;
547 	int flags, len, error, type;
548 	const struct protosw	*pr;
549 	struct mbuf *nextrecord;
550 
551 	KASSERT(mp0 != NULL);
552 
553 	flags = MSG_DONTWAIT;
554 	pr = so->so_proto;
555 	mp = mp0;
556 	type = 0;
557 
558 	*mp = NULL;
559 
560 	KASSERT(pr->pr_flags & PR_ATOMIC);
561  restart:
562 	if ((error = sblock(&so->so_rcv, M_NOWAIT)) != 0) {
563 		return error;
564 	}
565 	m = so->so_rcv.sb_mb;
566 	/*
567 	 * If we have less data than requested, do not block awaiting more.
568 	 */
569 	if (m == NULL) {
570 #ifdef DIAGNOSTIC
571 		if (so->so_rcv.sb_cc)
572 			panic("receive 1");
573 #endif
574 		if (so->so_error) {
575 			error = so->so_error;
576 			so->so_error = 0;
577 		} else if (so->so_state & SS_CANTRCVMORE)
578 			;
579 		else if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0
580 		      && (so->so_proto->pr_flags & PR_CONNREQUIRED))
581 			error = ENOTCONN;
582 		else
583 			error = EWOULDBLOCK;
584 		goto release;
585 	}
586 	/*
587 	 * On entry here, m points to the first record of the socket buffer.
588 	 * While we process the initial mbufs containing address and control
589 	 * info, we save a copy of m->m_nextpkt into nextrecord.
590 	 */
591 	if (curlwp != NULL)
592 		curlwp->l_ru.ru_msgrcv++;
593 	KASSERT(m == so->so_rcv.sb_mb);
594 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 1");
595 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 1");
596 	nextrecord = m->m_nextpkt;
597 	if (pr->pr_flags & PR_ADDR) {
598 #ifdef DIAGNOSTIC
599 		if (m->m_type != MT_SONAME)
600 			panic("receive 1a");
601 #endif
602 		sbfree(&so->so_rcv, m);
603 		MFREE(m, so->so_rcv.sb_mb);
604 		m = so->so_rcv.sb_mb;
605 	}
606 	while (m != NULL && m->m_type == MT_CONTROL && error == 0) {
607 		sbfree(&so->so_rcv, m);
608 		/*
609 		 * Dispose of any SCM_RIGHTS message that went
610 		 * through the read path rather than recv.
611 		 */
612 		if (pr->pr_domain->dom_dispose &&
613 		    mtod(m, struct cmsghdr *)->cmsg_type == SCM_RIGHTS)
614 			(*pr->pr_domain->dom_dispose)(m);
615 		MFREE(m, so->so_rcv.sb_mb);
616 		m = so->so_rcv.sb_mb;
617 	}
618 
619 	/*
620 	 * If m is non-NULL, we have some data to read.  From now on,
621 	 * make sure to keep sb_lastrecord consistent when working on
622 	 * the last packet on the chain (nextrecord == NULL) and we
623 	 * change m->m_nextpkt.
624 	 */
625 	if (m != NULL) {
626 		m->m_nextpkt = nextrecord;
627 		/*
628 		 * If nextrecord == NULL (this is a single chain),
629 		 * then sb_lastrecord may not be valid here if m
630 		 * was changed earlier.
631 		 */
632 		if (nextrecord == NULL) {
633 			KASSERT(so->so_rcv.sb_mb == m);
634 			so->so_rcv.sb_lastrecord = m;
635 		}
636 		type = m->m_type;
637 		if (type == MT_OOBDATA)
638 			flags |= MSG_OOB;
639 	} else {
640 		KASSERT(so->so_rcv.sb_mb == m);
641 		so->so_rcv.sb_mb = nextrecord;
642 		SB_EMPTY_FIXUP(&so->so_rcv);
643 	}
644 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 2");
645 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 2");
646 
647 	while (m != NULL) {
648 		if (m->m_type == MT_OOBDATA) {
649 			if (type != MT_OOBDATA)
650 				break;
651 		} else if (type == MT_OOBDATA)
652 			break;
653 #ifdef DIAGNOSTIC
654 		else if (m->m_type != MT_DATA && m->m_type != MT_HEADER)
655 			panic("receive 3");
656 #endif
657 		so->so_state &= ~SS_RCVATMARK;
658 		if (so->so_oobmark != 0 && so->so_oobmark < m->m_len)
659 			break;
660 		len = m->m_len;
661 		/*
662 		 * mp is set, just pass back the mbufs.
663 		 * Sockbuf must be consistent here (points to current mbuf,
664 		 * it points to next record) when we drop priority;
665 		 * we must note any additions to the sockbuf when we
666 		 * block interrupts again.
667 		 */
668 		if (m->m_flags & M_EOR)
669 			flags |= MSG_EOR;
670 		nextrecord = m->m_nextpkt;
671 		sbfree(&so->so_rcv, m);
672 		*mp = m;
673 		mp = &m->m_next;
674 		so->so_rcv.sb_mb = m = m->m_next;
675 		*mp = NULL;
676 		/*
677 		 * If m != NULL, we also know that
678 		 * so->so_rcv.sb_mb != NULL.
679 		 */
680 		KASSERT(so->so_rcv.sb_mb == m);
681 		if (m) {
682 			m->m_nextpkt = nextrecord;
683 			if (nextrecord == NULL)
684 				so->so_rcv.sb_lastrecord = m;
685 		} else {
686 			so->so_rcv.sb_mb = nextrecord;
687 			SB_EMPTY_FIXUP(&so->so_rcv);
688 		}
689 		SBLASTRECORDCHK(&so->so_rcv, "soreceive 3");
690 		SBLASTMBUFCHK(&so->so_rcv, "soreceive 3");
691 		if (so->so_oobmark) {
692 			so->so_oobmark -= len;
693 			if (so->so_oobmark == 0) {
694 				so->so_state |= SS_RCVATMARK;
695 				break;
696 			}
697 		}
698 		if (flags & MSG_EOR)
699 			break;
700 	}
701 
702 	if (m != NULL) {
703 		m_freem(*mp);
704 		*mp = NULL;
705 		error = ENOMEM;
706 		(void) sbdroprecord(&so->so_rcv);
707 	} else {
708 		/*
709 		 * First part is an inline SB_EMPTY_FIXUP().  Second
710 		 * part makes sure sb_lastrecord is up-to-date if
711 		 * there is still data in the socket buffer.
712 		 */
713 		so->so_rcv.sb_mb = nextrecord;
714 		if (so->so_rcv.sb_mb == NULL) {
715 			so->so_rcv.sb_mbtail = NULL;
716 			so->so_rcv.sb_lastrecord = NULL;
717 		} else if (nextrecord->m_nextpkt == NULL)
718 			so->so_rcv.sb_lastrecord = nextrecord;
719 	}
720 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 4");
721 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 4");
722 	if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
723 		(*pr->pr_usrreqs->pr_rcvd)(so, flags, curlwp);
724 	if (*mp0 == NULL && (flags & MSG_EOR) == 0 &&
725 	    (so->so_state & SS_CANTRCVMORE) == 0) {
726 		sbunlock(&so->so_rcv);
727 		goto restart;
728 	}
729 
730  release:
731 	sbunlock(&so->so_rcv);
732 	return error;
733 }
734 
735 static struct socket *
736 gre_reconf(struct gre_softc *sc, const struct gre_soparm *newsoparm)
737 {
738 	struct ifnet *ifp = &sc->sc_if;
739 
740 	GRE_DPRINTF(sc, "enter\n");
741 
742 shutdown:
743 	if (sc->sc_soparm.sp_so != NULL) {
744 		GRE_DPRINTF(sc, "\n");
745 		gre_upcall_remove(sc->sc_soparm.sp_so);
746 		softint_disestablish(sc->sc_si);
747 		sc->sc_si = NULL;
748 		gre_fp_send(sc, GRE_M_DELFP, NULL);
749 		gre_clearconf(&sc->sc_soparm, false);
750 	}
751 
752 	if (newsoparm != NULL) {
753 		GRE_DPRINTF(sc, "\n");
754 		sc->sc_soparm = *newsoparm;
755 		newsoparm = NULL;
756 	}
757 
758 	if (sc->sc_soparm.sp_so != NULL) {
759 		GRE_DPRINTF(sc, "\n");
760 		sc->sc_si = softint_establish(SOFTINT_NET, greintr, sc);
761 		gre_upcall_add(sc->sc_soparm.sp_so, sc);
762 		if ((ifp->if_flags & IFF_UP) == 0) {
763 			GRE_DPRINTF(sc, "down\n");
764 			goto shutdown;
765 		}
766 	}
767 
768 	GRE_DPRINTF(sc, "\n");
769 	if (sc->sc_soparm.sp_so != NULL)
770 		sc->sc_if.if_flags |= IFF_RUNNING;
771 	else {
772 		gre_bufq_purge(&sc->sc_snd);
773 		sc->sc_if.if_flags &= ~IFF_RUNNING;
774 	}
775 	return sc->sc_soparm.sp_so;
776 }
777 
778 static int
779 gre_input(struct gre_softc *sc, struct mbuf *m, int hlen,
780     const struct gre_h *gh)
781 {
782 	pktqueue_t *pktq = NULL;
783 	struct ifqueue *ifq = NULL;
784 	uint16_t flags;
785 	uint32_t af;		/* af passed to BPF tap */
786 	int isr = 0, s;
787 
788 	sc->sc_if.if_ipackets++;
789 	sc->sc_if.if_ibytes += m->m_pkthdr.len;
790 
791 	hlen += sizeof(struct gre_h);
792 
793 	/* process GRE flags as packet can be of variable len */
794 	flags = ntohs(gh->flags);
795 
796 	/* Checksum & Offset are present */
797 	if ((flags & GRE_CP) | (flags & GRE_RP))
798 		hlen += 4;
799 	/* We don't support routing fields (variable length) */
800 	if (flags & GRE_RP) {
801 		sc->sc_if.if_ierrors++;
802 		return 0;
803 	}
804 	if (flags & GRE_KP)
805 		hlen += 4;
806 	if (flags & GRE_SP)
807 		hlen += 4;
808 
809 	switch (ntohs(gh->ptype)) { /* ethertypes */
810 #ifdef INET
811 	case ETHERTYPE_IP:
812 		pktq = ip_pktq;
813 		af = AF_INET;
814 		break;
815 #endif
816 #ifdef NETATALK
817 	case ETHERTYPE_ATALK:
818 		ifq = &atintrq1;
819 		isr = NETISR_ATALK;
820 		af = AF_APPLETALK;
821 		break;
822 #endif
823 #ifdef INET6
824 	case ETHERTYPE_IPV6:
825 		pktq = ip6_pktq;
826 		af = AF_INET6;
827 		break;
828 #endif
829 #ifdef MPLS
830 	case ETHERTYPE_MPLS:
831 		ifq = &mplsintrq;
832 		isr = NETISR_MPLS;
833 		af = AF_MPLS;
834 		break;
835 #endif
836 	default:	   /* others not yet supported */
837 		GRE_DPRINTF(sc, "unhandled ethertype 0x%04x\n",
838 		    ntohs(gh->ptype));
839 		sc->sc_if.if_noproto++;
840 		return 0;
841 	}
842 
843 	if (hlen > m->m_pkthdr.len) {
844 		m_freem(m);
845 		sc->sc_if.if_ierrors++;
846 		return EINVAL;
847 	}
848 	m_adj(m, hlen);
849 
850 	bpf_mtap_af(&sc->sc_if, af, m);
851 
852 	m->m_pkthdr.rcvif = &sc->sc_if;
853 
854 	if (__predict_true(pktq)) {
855 		if (__predict_false(!pktq_enqueue(pktq, m, 0))) {
856 			m_freem(m);
857 		}
858 		return 1;
859 	}
860 
861 	s = splnet();
862 	if (IF_QFULL(ifq)) {
863 		IF_DROP(ifq);
864 		m_freem(m);
865 	} else {
866 		IF_ENQUEUE(ifq, m);
867 	}
868 	/* we need schednetisr since the address family may change */
869 	schednetisr(isr);
870 	splx(s);
871 
872 	return 1;	/* packet is done, no further processing needed */
873 }
874 
875 /*
876  * The output routine. Takes a packet and encapsulates it in the protocol
877  * given by sc->sc_soparm.sp_proto. See also RFC 1701 and RFC 2004
878  */
879 static int
880 gre_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
881 	   struct rtentry *rt)
882 {
883 	int error = 0;
884 	struct gre_softc *sc = ifp->if_softc;
885 	struct gre_h *gh;
886 	uint16_t etype = 0;
887 
888 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) {
889 		m_freem(m);
890 		error = ENETDOWN;
891 		goto end;
892 	}
893 
894 	bpf_mtap_af(ifp, dst->sa_family, m);
895 
896 	m->m_flags &= ~(M_BCAST|M_MCAST);
897 
898 	GRE_DPRINTF(sc, "dst->sa_family=%d\n", dst->sa_family);
899 	switch (dst->sa_family) {
900 #ifdef INET
901 	case AF_INET:
902 		/* TBD Extract the IP ToS field and set the
903 		 * encapsulating protocol's ToS to suit.
904 		 */
905 		etype = htons(ETHERTYPE_IP);
906 		break;
907 #endif
908 #ifdef NETATALK
909 	case AF_APPLETALK:
910 		etype = htons(ETHERTYPE_ATALK);
911 		break;
912 #endif
913 #ifdef INET6
914 	case AF_INET6:
915 		etype = htons(ETHERTYPE_IPV6);
916 		break;
917 #endif
918 	default:
919 		IF_DROP(&ifp->if_snd);
920 		m_freem(m);
921 		error = EAFNOSUPPORT;
922 		goto end;
923 	}
924 
925 #ifdef MPLS
926 		if (rt != NULL && rt_gettag(rt) != NULL) {
927 			union mpls_shim msh;
928 			msh.s_addr = MPLS_GETSADDR(rt);
929 			if (msh.shim.label != MPLS_LABEL_IMPLNULL)
930 				etype = htons(ETHERTYPE_MPLS);
931 		}
932 #endif
933 
934 	M_PREPEND(m, sizeof(*gh), M_DONTWAIT);
935 
936 	if (m == NULL) {
937 		IF_DROP(&ifp->if_snd);
938 		error = ENOBUFS;
939 		goto end;
940 	}
941 
942 	gh = mtod(m, struct gre_h *);
943 	gh->flags = 0;
944 	gh->ptype = etype;
945 	/* XXX Need to handle IP ToS.  Look at how I handle IP TTL. */
946 
947 	ifp->if_opackets++;
948 	ifp->if_obytes += m->m_pkthdr.len;
949 
950 	/* Clear checksum-offload flags. */
951 	m->m_pkthdr.csum_flags = 0;
952 	m->m_pkthdr.csum_data = 0;
953 
954 	/* send it off */
955 	if ((error = gre_bufq_enqueue(&sc->sc_snd, m)) != 0) {
956 		sc->sc_oflow_ev.ev_count++;
957 		m_freem(m);
958 	} else
959 		softint_schedule(sc->sc_si);
960   end:
961 	if (error)
962 		ifp->if_oerrors++;
963 	return error;
964 }
965 
966 static int
967 gre_getsockname(struct socket *so, struct sockaddr *nam)
968 {
969 	return (*so->so_proto->pr_usrreqs->pr_sockaddr)(so, nam);
970 }
971 
972 static int
973 gre_getpeername(struct socket *so, struct sockaddr *nam)
974 {
975 	return (*so->so_proto->pr_usrreqs->pr_peeraddr)(so, nam);
976 }
977 
978 static int
979 gre_getnames(struct socket *so, struct lwp *l, struct sockaddr_storage *src,
980     struct sockaddr_storage *dst)
981 {
982 	struct sockaddr_storage ss;
983 	int rc;
984 
985 	solock(so);
986 	if ((rc = gre_getsockname(so, (struct sockaddr *)&ss)) != 0)
987 		goto out;
988 	*src = ss;
989 
990 	if ((rc = gre_getpeername(so, (struct sockaddr *)&ss)) != 0)
991 		goto out;
992 	*dst = ss;
993 out:
994 	sounlock(so);
995 	return rc;
996 }
997 
998 static void
999 gre_fp_recvloop(void *arg)
1000 {
1001 	struct gre_softc *sc = arg;
1002 
1003 	mutex_enter(&sc->sc_mtx);
1004 	while (gre_fp_recv(sc))
1005 		;
1006 	mutex_exit(&sc->sc_mtx);
1007 	kthread_exit(0);
1008 }
1009 
1010 static bool
1011 gre_fp_recv(struct gre_softc *sc)
1012 {
1013 	int fd, ofd, rc;
1014 	file_t *fp;
1015 
1016 	fp = sc->sc_fp;
1017 	ofd = sc->sc_fd;
1018 	fd = -1;
1019 
1020 	switch (sc->sc_msg) {
1021 	case GRE_M_STOP:
1022 		cv_signal(&sc->sc_fp_condvar);
1023 		return false;
1024 	case GRE_M_SETFP:
1025 		mutex_exit(&sc->sc_mtx);
1026 		rc = fd_dup(fp, 0, &fd, 0);
1027 		mutex_enter(&sc->sc_mtx);
1028 		if (rc != 0) {
1029 			sc->sc_msg = GRE_M_ERR;
1030 			break;
1031 		}
1032 		/*FALLTHROUGH*/
1033 	case GRE_M_DELFP:
1034 		mutex_exit(&sc->sc_mtx);
1035 		if (ofd != -1 && fd_getfile(ofd) != NULL)
1036 			fd_close(ofd);
1037 		mutex_enter(&sc->sc_mtx);
1038 		sc->sc_fd = fd;
1039 		sc->sc_msg = GRE_M_OK;
1040 		break;
1041 	default:
1042 		gre_fp_wait(sc);
1043 		return true;
1044 	}
1045 	cv_signal(&sc->sc_fp_condvar);
1046 	return true;
1047 }
1048 
1049 static bool
1050 gre_fp_send(struct gre_softc *sc, enum gre_msg msg, file_t *fp)
1051 {
1052 	bool rc;
1053 
1054 	mutex_enter(&sc->sc_mtx);
1055 	while (sc->sc_msg != GRE_M_NONE)
1056 		gre_fp_wait(sc);
1057 	sc->sc_fp = fp;
1058 	sc->sc_msg = msg;
1059 	cv_signal(&sc->sc_fp_condvar);
1060 	while (sc->sc_msg != GRE_M_STOP && sc->sc_msg != GRE_M_OK &&
1061 	            sc->sc_msg != GRE_M_ERR)
1062 		gre_fp_wait(sc);
1063 	rc = (sc->sc_msg != GRE_M_ERR);
1064 	sc->sc_msg = GRE_M_NONE;
1065 	cv_signal(&sc->sc_fp_condvar);
1066 	mutex_exit(&sc->sc_mtx);
1067 	return rc;
1068 }
1069 
1070 static int
1071 gre_ssock(struct ifnet *ifp, struct gre_soparm *sp, int fd)
1072 {
1073 	int error = 0;
1074 	const struct protosw *pr;
1075 	file_t *fp;
1076 	struct gre_softc *sc = ifp->if_softc;
1077 	struct socket *so;
1078 	struct sockaddr_storage dst, src;
1079 
1080 	if ((fp = fd_getfile(fd)) == NULL)
1081 		return EBADF;
1082 	if (fp->f_type != DTYPE_SOCKET) {
1083 		fd_putfile(fd);
1084 		return ENOTSOCK;
1085 	}
1086 
1087 	GRE_DPRINTF(sc, "\n");
1088 
1089 	so = fp->f_socket;
1090 	pr = so->so_proto;
1091 
1092 	GRE_DPRINTF(sc, "type %d, proto %d\n", pr->pr_type, pr->pr_protocol);
1093 
1094 	if ((pr->pr_flags & PR_ATOMIC) == 0 ||
1095 	    (sp->sp_type != 0 && pr->pr_type != sp->sp_type) ||
1096 	    (sp->sp_proto != 0 && pr->pr_protocol != 0 &&
1097 	     pr->pr_protocol != sp->sp_proto)) {
1098 		error = EINVAL;
1099 		goto err;
1100 	}
1101 
1102 	GRE_DPRINTF(sc, "\n");
1103 
1104 	/* check address */
1105 	if ((error = gre_getnames(so, curlwp, &src, &dst)) != 0)
1106 		goto err;
1107 
1108 	GRE_DPRINTF(sc, "\n");
1109 
1110 	if (!gre_fp_send(sc, GRE_M_SETFP, fp)) {
1111 		error = EBUSY;
1112 		goto err;
1113 	}
1114 
1115 	GRE_DPRINTF(sc, "\n");
1116 
1117 	sp->sp_src = src;
1118 	sp->sp_dst = dst;
1119 
1120 	sp->sp_so = so;
1121 
1122 err:
1123 	fd_putfile(fd);
1124 	return error;
1125 }
1126 
1127 static bool
1128 sockaddr_is_anyaddr(const struct sockaddr *sa)
1129 {
1130 	socklen_t anylen, salen;
1131 	const void *anyaddr, *addr;
1132 
1133 	if ((anyaddr = sockaddr_anyaddr(sa, &anylen)) == NULL ||
1134 	    (addr = sockaddr_const_addr(sa, &salen)) == NULL)
1135 		return false;
1136 
1137 	if (salen > anylen)
1138 		return false;
1139 
1140 	return memcmp(anyaddr, addr, MIN(anylen, salen)) == 0;
1141 }
1142 
1143 static bool
1144 gre_is_nullconf(const struct gre_soparm *sp)
1145 {
1146 	return sockaddr_is_anyaddr(sstocsa(&sp->sp_src)) ||
1147 	       sockaddr_is_anyaddr(sstocsa(&sp->sp_dst));
1148 }
1149 
1150 static void
1151 gre_clearconf(struct gre_soparm *sp, bool force)
1152 {
1153 	if (sp->sp_bysock || force) {
1154 		sockaddr_copy(sstosa(&sp->sp_src), sizeof(sp->sp_src),
1155 		    sockaddr_any(sstosa(&sp->sp_src)));
1156 		sockaddr_copy(sstosa(&sp->sp_dst), sizeof(sp->sp_dst),
1157 		    sockaddr_any(sstosa(&sp->sp_dst)));
1158 		sp->sp_bysock = false;
1159 	}
1160 	sp->sp_so = NULL; /* XXX */
1161 }
1162 
1163 static int
1164 gre_ioctl(struct ifnet *ifp, const u_long cmd, void *data)
1165 {
1166 	struct ifreq *ifr;
1167 	struct ifaddr *ifa = (struct ifaddr *)data;
1168 	struct if_laddrreq *lifr = (struct if_laddrreq *)data;
1169 	struct gre_softc *sc = ifp->if_softc;
1170 	struct gre_soparm *sp;
1171 	int fd, error = 0, oproto, otype, s;
1172 	struct gre_soparm sp0;
1173 
1174 	ifr = data;
1175 
1176 	GRE_DPRINTF(sc, "cmd %lu\n", cmd);
1177 
1178 	switch (cmd) {
1179 	case GRESPROTO:
1180 	case GRESADDRD:
1181 	case GRESADDRS:
1182 	case GRESSOCK:
1183 	case GREDSOCK:
1184 		if (kauth_authorize_network(curlwp->l_cred,
1185 		    KAUTH_NETWORK_INTERFACE,
1186 		    KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
1187 		    NULL) != 0)
1188 			return EPERM;
1189 		break;
1190 	default:
1191 		break;
1192 	}
1193 
1194 	s = splnet();
1195 
1196 	sp0 = sc->sc_soparm;
1197 	sp0.sp_so = NULL;
1198 	sp = &sp0;
1199 
1200 	GRE_DPRINTF(sc, "\n");
1201 
1202 	switch (cmd) {
1203 	case SIOCINITIFADDR:
1204 		GRE_DPRINTF(sc, "\n");
1205 		if ((ifp->if_flags & IFF_UP) != 0)
1206 			break;
1207 		gre_clearconf(sp, false);
1208 		ifp->if_flags |= IFF_UP;
1209 		ifa->ifa_rtrequest = p2p_rtrequest;
1210 		goto mksocket;
1211 	case SIOCSIFFLAGS:
1212 		if ((error = ifioctl_common(ifp, cmd, data)) != 0)
1213 			break;
1214 		oproto = sp->sp_proto;
1215 		otype = sp->sp_type;
1216 		switch (ifr->ifr_flags & (IFF_LINK0|IFF_LINK2)) {
1217 		case IFF_LINK0|IFF_LINK2:
1218 			sp->sp_proto = IPPROTO_UDP;
1219 			sp->sp_type = SOCK_DGRAM;
1220 			break;
1221 		case IFF_LINK2:
1222 			sp->sp_proto = 0;
1223 			sp->sp_type = 0;
1224 			break;
1225 		case IFF_LINK0:
1226 			sp->sp_proto = IPPROTO_GRE;
1227 			sp->sp_type = SOCK_RAW;
1228 			break;
1229 		default:
1230 			GRE_DPRINTF(sc, "\n");
1231 			error = EINVAL;
1232 			goto out;
1233 		}
1234 		GRE_DPRINTF(sc, "\n");
1235 		gre_clearconf(sp, false);
1236 		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) ==
1237 		    (IFF_UP|IFF_RUNNING) &&
1238 		    (oproto == sp->sp_proto || sp->sp_proto == 0) &&
1239 		    (otype == sp->sp_type || sp->sp_type == 0))
1240 			break;
1241 		switch (sp->sp_proto) {
1242 		case IPPROTO_UDP:
1243 		case IPPROTO_GRE:
1244 			goto mksocket;
1245 		default:
1246 			break;
1247 		}
1248 		break;
1249 	case SIOCSIFMTU:
1250 		/* XXX determine MTU automatically by probing w/
1251 		 * XXX do-not-fragment packets?
1252 		 */
1253 		if (ifr->ifr_mtu < 576) {
1254 			error = EINVAL;
1255 			break;
1256 		}
1257 		/*FALLTHROUGH*/
1258 	case SIOCGIFMTU:
1259 		if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET)
1260 			error = 0;
1261 		break;
1262 	case SIOCADDMULTI:
1263 	case SIOCDELMULTI:
1264 		if (ifr == NULL) {
1265 			error = EAFNOSUPPORT;
1266 			break;
1267 		}
1268 		switch (ifreq_getaddr(cmd, ifr)->sa_family) {
1269 #ifdef INET
1270 		case AF_INET:
1271 			break;
1272 #endif
1273 #ifdef INET6
1274 		case AF_INET6:
1275 			break;
1276 #endif
1277 		default:
1278 			error = EAFNOSUPPORT;
1279 			break;
1280 		}
1281 		break;
1282 	case GRESPROTO:
1283 		gre_clearconf(sp, false);
1284 		oproto = sp->sp_proto;
1285 		otype = sp->sp_type;
1286 		sp->sp_proto = ifr->ifr_flags;
1287 		switch (sp->sp_proto) {
1288 		case IPPROTO_UDP:
1289 			ifp->if_flags |= IFF_LINK0|IFF_LINK2;
1290 			sp->sp_type = SOCK_DGRAM;
1291 			break;
1292 		case IPPROTO_GRE:
1293 			ifp->if_flags |= IFF_LINK0;
1294 			ifp->if_flags &= ~IFF_LINK2;
1295 			sp->sp_type = SOCK_RAW;
1296 			break;
1297 		case 0:
1298 			ifp->if_flags &= ~IFF_LINK0;
1299 			ifp->if_flags |= IFF_LINK2;
1300 			sp->sp_type = 0;
1301 			break;
1302 		default:
1303 			error = EPROTONOSUPPORT;
1304 			break;
1305 		}
1306 		if ((oproto == sp->sp_proto || sp->sp_proto == 0) &&
1307 		    (otype == sp->sp_type || sp->sp_type == 0))
1308 			break;
1309 		switch (sp->sp_proto) {
1310 		case IPPROTO_UDP:
1311 		case IPPROTO_GRE:
1312 			goto mksocket;
1313 		default:
1314 			break;
1315 		}
1316 		break;
1317 	case GREGPROTO:
1318 		ifr->ifr_flags = sp->sp_proto;
1319 		break;
1320 	case GRESADDRS:
1321 	case GRESADDRD:
1322 		gre_clearconf(sp, false);
1323 		/* set tunnel endpoints and mark interface as up */
1324 		switch (cmd) {
1325 		case GRESADDRS:
1326 			sockaddr_copy(sstosa(&sp->sp_src),
1327 			    sizeof(sp->sp_src), ifreq_getaddr(cmd, ifr));
1328 			break;
1329 		case GRESADDRD:
1330 			sockaddr_copy(sstosa(&sp->sp_dst),
1331 			    sizeof(sp->sp_dst), ifreq_getaddr(cmd, ifr));
1332 			break;
1333 		}
1334 	checkaddr:
1335 		if (sockaddr_any(sstosa(&sp->sp_src)) == NULL ||
1336 		    sockaddr_any(sstosa(&sp->sp_dst)) == NULL) {
1337 			error = EINVAL;
1338 			break;
1339 		}
1340 		/* let gre_socreate() check the rest */
1341 	mksocket:
1342 		GRE_DPRINTF(sc, "\n");
1343 		/* If we're administratively down, or the configuration
1344 		 * is empty, there's no use creating a socket.
1345 		 */
1346 		if ((ifp->if_flags & IFF_UP) == 0 || gre_is_nullconf(sp))
1347 			goto sendconf;
1348 
1349 		GRE_DPRINTF(sc, "\n");
1350 		fd = 0;
1351 		error = gre_socreate(sc, sp, &fd);
1352 		if (error != 0)
1353 			break;
1354 
1355 	setsock:
1356 		GRE_DPRINTF(sc, "\n");
1357 
1358 		error = gre_ssock(ifp, sp, fd);
1359 
1360 		if (cmd != GRESSOCK) {
1361 			GRE_DPRINTF(sc, "\n");
1362 			/* XXX v. dodgy */
1363 			if (fd_getfile(fd) != NULL)
1364 				fd_close(fd);
1365 		}
1366 
1367 		if (error == 0) {
1368 	sendconf:
1369 			GRE_DPRINTF(sc, "\n");
1370 			ifp->if_flags &= ~IFF_RUNNING;
1371 			gre_reconf(sc, sp);
1372 		}
1373 
1374 		break;
1375 	case GREGADDRS:
1376 		ifreq_setaddr(cmd, ifr, sstosa(&sp->sp_src));
1377 		break;
1378 	case GREGADDRD:
1379 		ifreq_setaddr(cmd, ifr, sstosa(&sp->sp_dst));
1380 		break;
1381 	case GREDSOCK:
1382 		GRE_DPRINTF(sc, "\n");
1383 		if (sp->sp_bysock)
1384 			ifp->if_flags &= ~IFF_UP;
1385 		gre_clearconf(sp, false);
1386 		goto mksocket;
1387 	case GRESSOCK:
1388 		GRE_DPRINTF(sc, "\n");
1389 		gre_clearconf(sp, true);
1390 		fd = (int)ifr->ifr_value;
1391 		sp->sp_bysock = true;
1392 		ifp->if_flags |= IFF_UP;
1393 		goto setsock;
1394 	case SIOCSLIFPHYADDR:
1395 		GRE_DPRINTF(sc, "\n");
1396 		if (lifr->addr.ss_family != lifr->dstaddr.ss_family) {
1397 			error = EAFNOSUPPORT;
1398 			break;
1399 		}
1400 		sockaddr_copy(sstosa(&sp->sp_src), sizeof(sp->sp_src),
1401 		    sstosa(&lifr->addr));
1402 		sockaddr_copy(sstosa(&sp->sp_dst), sizeof(sp->sp_dst),
1403 		    sstosa(&lifr->dstaddr));
1404 		GRE_DPRINTF(sc, "\n");
1405 		goto checkaddr;
1406 	case SIOCDIFPHYADDR:
1407 		GRE_DPRINTF(sc, "\n");
1408 		gre_clearconf(sp, true);
1409 		ifp->if_flags &= ~IFF_UP;
1410 		goto mksocket;
1411 	case SIOCGLIFPHYADDR:
1412 		GRE_DPRINTF(sc, "\n");
1413 		if (gre_is_nullconf(sp)) {
1414 			error = EADDRNOTAVAIL;
1415 			break;
1416 		}
1417 		sockaddr_copy(sstosa(&lifr->addr), sizeof(lifr->addr),
1418 		    sstosa(&sp->sp_src));
1419 		sockaddr_copy(sstosa(&lifr->dstaddr), sizeof(lifr->dstaddr),
1420 		    sstosa(&sp->sp_dst));
1421 		GRE_DPRINTF(sc, "\n");
1422 		break;
1423 	default:
1424 		error = ifioctl_common(ifp, cmd, data);
1425 		break;
1426 	}
1427 out:
1428 	GRE_DPRINTF(sc, "\n");
1429 	splx(s);
1430 	return error;
1431 }
1432 
1433 /* ARGSUSED */
1434 void
1435 greattach(int count)
1436 {
1437 	if_clone_attach(&gre_cloner);
1438 }
1439