xref: /netbsd-src/sys/net/if_gre.c (revision bbde328be4e75ea9ad02e9715ea13ca54b797ada)
1 /*	$NetBSD: if_gre.c,v 1.143 2010/04/05 07:22:23 joerg 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 1.143 2010/04/05 07:22:23 joerg Exp $");
49 
50 #include "opt_atalk.h"
51 #include "opt_gre.h"
52 #include "opt_inet.h"
53 
54 #include <sys/param.h>
55 #include <sys/file.h>
56 #include <sys/filedesc.h>
57 #include <sys/malloc.h>
58 #include <sys/mallocvar.h>
59 #include <sys/mbuf.h>
60 #include <sys/proc.h>
61 #include <sys/domain.h>
62 #include <sys/protosw.h>
63 #include <sys/socket.h>
64 #include <sys/socketvar.h>
65 #include <sys/ioctl.h>
66 #include <sys/queue.h>
67 #include <sys/intr.h>
68 #include <sys/systm.h>
69 #include <sys/sysctl.h>
70 #include <sys/kauth.h>
71 
72 #include <sys/kernel.h>
73 #include <sys/mutex.h>
74 #include <sys/condvar.h>
75 #include <sys/kthread.h>
76 
77 #include <sys/cpu.h>
78 
79 #include <net/ethertypes.h>
80 #include <net/if.h>
81 #include <net/if_types.h>
82 #include <net/netisr.h>
83 #include <net/route.h>
84 
85 #include <netinet/in_systm.h>
86 #include <netinet/in.h>
87 #include <netinet/ip.h> /* we always need this for sizeof(struct ip) */
88 
89 #ifdef INET
90 #include <netinet/in_var.h>
91 #include <netinet/ip_var.h>
92 #endif
93 
94 #ifdef INET6
95 #include <netinet6/in6_var.h>
96 #endif
97 
98 #ifdef NETATALK
99 #include <netatalk/at.h>
100 #include <netatalk/at_var.h>
101 #include <netatalk/at_extern.h>
102 #endif
103 
104 #include <sys/time.h>
105 #include <net/bpf.h>
106 
107 #include <net/if_gre.h>
108 
109 #include <compat/sys/socket.h>
110 #include <compat/sys/sockio.h>
111 /*
112  * It is not easy to calculate the right value for a GRE MTU.
113  * We leave this task to the admin and use the same default that
114  * other vendors use.
115  */
116 #define GREMTU 1476
117 
118 #ifdef GRE_DEBUG
119 int gre_debug = 0;
120 #define	GRE_DPRINTF(__sc, ...)						\
121 	do {								\
122 		if (__predict_false(gre_debug ||			\
123 		    ((__sc)->sc_if.if_flags & IFF_DEBUG) != 0)) {	\
124 			printf("%s.%d: ", __func__, __LINE__);		\
125 			printf(__VA_ARGS__);				\
126 		}							\
127 	} while (/*CONSTCOND*/0)
128 #else
129 #define	GRE_DPRINTF(__sc, __fmt, ...)	do { } while (/*CONSTCOND*/0)
130 #endif /* GRE_DEBUG */
131 
132 int ip_gre_ttl = GRE_TTL;
133 MALLOC_DEFINE(M_GRE_BUFQ, "gre_bufq", "gre mbuf queue");
134 
135 static int gre_clone_create(struct if_clone *, int);
136 static int gre_clone_destroy(struct ifnet *);
137 
138 static struct if_clone gre_cloner =
139     IF_CLONE_INITIALIZER("gre", gre_clone_create, gre_clone_destroy);
140 
141 static int gre_input(struct gre_softc *, struct mbuf *, int,
142     const struct gre_h *);
143 static bool gre_is_nullconf(const struct gre_soparm *);
144 static int gre_output(struct ifnet *, struct mbuf *,
145 			   const struct sockaddr *, struct rtentry *);
146 static int gre_ioctl(struct ifnet *, u_long, void *);
147 static int gre_getsockname(struct socket *, struct mbuf *, struct lwp *);
148 static int gre_getpeername(struct socket *, struct mbuf *, struct lwp *);
149 static int gre_getnames(struct socket *, struct lwp *,
150     struct sockaddr_storage *, struct sockaddr_storage *);
151 static void gre_clearconf(struct gre_soparm *, bool);
152 static int gre_soreceive(struct socket *, struct mbuf **);
153 static int gre_sosend(struct socket *, struct mbuf *);
154 static struct socket *gre_reconf(struct gre_softc *, const struct gre_soparm *);
155 
156 static bool gre_fp_send(struct gre_softc *, enum gre_msg, file_t *);
157 static bool gre_fp_recv(struct gre_softc *);
158 static void gre_fp_recvloop(void *);
159 
160 static int
161 nearest_pow2(size_t len0)
162 {
163 	size_t len, mid;
164 
165 	if (len0 == 0)
166 		return 1;
167 
168 	for (len = len0; (len & (len - 1)) != 0; len &= len - 1)
169 		;
170 
171 	mid = len | (len >> 1);
172 
173 	/* avoid overflow */
174 	if ((len << 1) < len)
175 		return len;
176 	if (len0 >= mid)
177 		return len << 1;
178 	return len;
179 }
180 
181 static struct gre_bufq *
182 gre_bufq_init(struct gre_bufq *bq, size_t len0)
183 {
184 	size_t len;
185 
186 	len = nearest_pow2(len0);
187 
188 	memset(bq, 0, sizeof(*bq));
189 	bq->bq_buf = malloc(len * sizeof(struct mbuf *), M_GRE_BUFQ, M_WAITOK);
190 	bq->bq_len = len;
191 	bq->bq_lenmask = len - 1;
192 
193 	return bq;
194 }
195 
196 static bool
197 gre_bufq_empty(struct gre_bufq *bq)
198 {
199 	return bq->bq_prodidx == bq->bq_considx;
200 }
201 
202 static struct mbuf *
203 gre_bufq_dequeue(struct gre_bufq *bq)
204 {
205 	struct mbuf *m;
206 
207 	if (gre_bufq_empty(bq))
208 		return NULL;
209 
210 	m = bq->bq_buf[bq->bq_considx];
211 	bq->bq_considx = (bq->bq_considx + 1) & bq->bq_lenmask;
212 
213 	return m;
214 }
215 
216 static void
217 gre_bufq_purge(struct gre_bufq *bq)
218 {
219 	struct mbuf *m;
220 
221 	while ((m = gre_bufq_dequeue(bq)) != NULL)
222 		m_freem(m);
223 }
224 
225 static int
226 gre_bufq_enqueue(struct gre_bufq *bq, struct mbuf *m)
227 {
228 	int next;
229 
230 	next = (bq->bq_prodidx + 1) & bq->bq_lenmask;
231 
232 	if (next == bq->bq_considx) {
233 		bq->bq_drops++;
234 		return ENOBUFS;
235 	}
236 
237 	bq->bq_buf[bq->bq_prodidx] = m;
238 	bq->bq_prodidx = next;
239 	return 0;
240 }
241 
242 static void
243 greintr(void *arg)
244 {
245 	struct gre_softc *sc = (struct gre_softc *)arg;
246 	struct socket *so = sc->sc_soparm.sp_so;
247 	int rc;
248 	struct mbuf *m;
249 
250 	KASSERT(so != NULL);
251 
252 	sc->sc_send_ev.ev_count++;
253 	GRE_DPRINTF(sc, "enter\n");
254 	while ((m = gre_bufq_dequeue(&sc->sc_snd)) != NULL) {
255 		/* XXX handle ENOBUFS? */
256 		if ((rc = gre_sosend(so, m)) != 0)
257 			GRE_DPRINTF(sc, "gre_sosend failed %d\n", rc);
258 	}
259 }
260 
261 /* Caller must hold sc->sc_mtx. */
262 static void
263 gre_wait(struct gre_softc *sc)
264 {
265 	sc->sc_waiters++;
266 	cv_wait(&sc->sc_condvar, &sc->sc_mtx);
267 	sc->sc_waiters--;
268 }
269 
270 static void
271 gre_fp_wait(struct gre_softc *sc)
272 {
273 	sc->sc_fp_waiters++;
274 	cv_wait(&sc->sc_fp_condvar, &sc->sc_mtx);
275 	sc->sc_fp_waiters--;
276 }
277 
278 static void
279 gre_evcnt_detach(struct gre_softc *sc)
280 {
281 	evcnt_detach(&sc->sc_unsupp_ev);
282 	evcnt_detach(&sc->sc_pullup_ev);
283 	evcnt_detach(&sc->sc_error_ev);
284 	evcnt_detach(&sc->sc_block_ev);
285 	evcnt_detach(&sc->sc_recv_ev);
286 
287 	evcnt_detach(&sc->sc_oflow_ev);
288 	evcnt_detach(&sc->sc_send_ev);
289 }
290 
291 static void
292 gre_evcnt_attach(struct gre_softc *sc)
293 {
294 	evcnt_attach_dynamic(&sc->sc_recv_ev, EVCNT_TYPE_MISC,
295 	    NULL, sc->sc_if.if_xname, "recv");
296 	evcnt_attach_dynamic(&sc->sc_block_ev, EVCNT_TYPE_MISC,
297 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "would block");
298 	evcnt_attach_dynamic(&sc->sc_error_ev, EVCNT_TYPE_MISC,
299 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "error");
300 	evcnt_attach_dynamic(&sc->sc_pullup_ev, EVCNT_TYPE_MISC,
301 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "pullup failed");
302 	evcnt_attach_dynamic(&sc->sc_unsupp_ev, EVCNT_TYPE_MISC,
303 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "unsupported");
304 
305 	evcnt_attach_dynamic(&sc->sc_send_ev, EVCNT_TYPE_MISC,
306 	    NULL, sc->sc_if.if_xname, "send");
307 	evcnt_attach_dynamic(&sc->sc_oflow_ev, EVCNT_TYPE_MISC,
308 	    &sc->sc_send_ev, sc->sc_if.if_xname, "overflow");
309 }
310 
311 static int
312 gre_clone_create(struct if_clone *ifc, int unit)
313 {
314 	int rc;
315 	struct gre_softc *sc;
316 	struct gre_soparm *sp;
317 	const struct sockaddr *any;
318 
319 	if ((any = sockaddr_any_by_family(AF_INET)) == NULL &&
320 	    (any = sockaddr_any_by_family(AF_INET6)) == NULL)
321 		return -1;
322 
323 	sc = malloc(sizeof(struct gre_softc), M_DEVBUF, M_WAITOK|M_ZERO);
324 	mutex_init(&sc->sc_mtx, MUTEX_DRIVER, IPL_SOFTNET);
325 	cv_init(&sc->sc_condvar, "gre wait");
326 	cv_init(&sc->sc_fp_condvar, "gre fp");
327 
328 	if_initname(&sc->sc_if, ifc->ifc_name, unit);
329 	sc->sc_if.if_softc = sc;
330 	sc->sc_if.if_type = IFT_TUNNEL;
331 	sc->sc_if.if_addrlen = 0;
332 	sc->sc_if.if_hdrlen = sizeof(struct ip) + sizeof(struct gre_h);
333 	sc->sc_if.if_dlt = DLT_NULL;
334 	sc->sc_if.if_mtu = GREMTU;
335 	sc->sc_if.if_flags = IFF_POINTOPOINT|IFF_MULTICAST;
336 	sc->sc_if.if_output = gre_output;
337 	sc->sc_if.if_ioctl = gre_ioctl;
338 	sp = &sc->sc_soparm;
339 	sockaddr_copy(sstosa(&sp->sp_dst), sizeof(sp->sp_dst), any);
340 	sockaddr_copy(sstosa(&sp->sp_src), sizeof(sp->sp_src), any);
341 	sp->sp_proto = IPPROTO_GRE;
342 	sp->sp_type = SOCK_RAW;
343 
344 	sc->sc_fd = -1;
345 
346 	rc = kthread_create(PRI_NONE, KTHREAD_MPSAFE, NULL, gre_fp_recvloop, sc,
347 	    NULL, sc->sc_if.if_xname);
348 
349 	if (rc != 0)
350 		return -1;
351 
352 	gre_evcnt_attach(sc);
353 
354 	gre_bufq_init(&sc->sc_snd, 17);
355 	sc->sc_if.if_flags |= IFF_LINK0;
356 	if_attach(&sc->sc_if);
357 	if_alloc_sadl(&sc->sc_if);
358 	bpf_attach(&sc->sc_if, DLT_NULL, sizeof(uint32_t));
359 	sc->sc_state = GRE_S_IDLE;
360 	return 0;
361 }
362 
363 static int
364 gre_clone_destroy(struct ifnet *ifp)
365 {
366 	int s;
367 	struct gre_softc *sc = ifp->if_softc;
368 
369 	GRE_DPRINTF(sc, "\n");
370 
371 	bpf_detach(ifp);
372 	s = splnet();
373 	if_detach(ifp);
374 
375 	/* Some LWPs may still wait in gre_ioctl_lock(), however,
376 	 * no new LWP will enter gre_ioctl_lock(), because ifunit()
377 	 * cannot locate the interface any longer.
378 	 */
379 	mutex_enter(&sc->sc_mtx);
380 	GRE_DPRINTF(sc, "\n");
381 	while (sc->sc_state != GRE_S_IDLE)
382 		gre_wait(sc);
383 	GRE_DPRINTF(sc, "\n");
384 	sc->sc_state = GRE_S_DIE;
385 	cv_broadcast(&sc->sc_condvar);
386 	while (sc->sc_waiters > 0)
387 		cv_wait(&sc->sc_condvar, &sc->sc_mtx);
388 	/* At this point, no other LWP will access the gre_softc, so
389 	 * we can release the mutex.
390 	 */
391 	mutex_exit(&sc->sc_mtx);
392 	GRE_DPRINTF(sc, "\n");
393 	/* Note that we must not hold the mutex while we call gre_reconf(). */
394 	gre_reconf(sc, NULL);
395 
396 	mutex_enter(&sc->sc_mtx);
397 	sc->sc_msg = GRE_M_STOP;
398 	cv_signal(&sc->sc_fp_condvar);
399 	while (sc->sc_fp_waiters > 0)
400 		cv_wait(&sc->sc_fp_condvar, &sc->sc_mtx);
401 	mutex_exit(&sc->sc_mtx);
402 
403 	splx(s);
404 
405 	cv_destroy(&sc->sc_condvar);
406 	cv_destroy(&sc->sc_fp_condvar);
407 	mutex_destroy(&sc->sc_mtx);
408 	gre_evcnt_detach(sc);
409 	free(sc, M_DEVBUF);
410 
411 	return 0;
412 }
413 
414 static void
415 gre_receive(struct socket *so, void *arg, int events, int waitflag)
416 {
417 	struct gre_softc *sc = (struct gre_softc *)arg;
418 	int rc;
419 	const struct gre_h *gh;
420 	struct mbuf *m;
421 
422 	GRE_DPRINTF(sc, "enter\n");
423 
424 	sc->sc_recv_ev.ev_count++;
425 
426 	rc = gre_soreceive(so, &m);
427 	/* TBD Back off if ECONNREFUSED (indicates
428 	 * ICMP Port Unreachable)?
429 	 */
430 	if (rc == EWOULDBLOCK) {
431 		GRE_DPRINTF(sc, "EWOULDBLOCK\n");
432 		sc->sc_block_ev.ev_count++;
433 		return;
434 	} else if (rc != 0 || m == NULL) {
435 		GRE_DPRINTF(sc, "%s: rc %d m %p\n",
436 		    sc->sc_if.if_xname, rc, (void *)m);
437 		sc->sc_error_ev.ev_count++;
438 		return;
439 	}
440 	if (m->m_len < sizeof(*gh) && (m = m_pullup(m, sizeof(*gh))) == NULL) {
441 		GRE_DPRINTF(sc, "m_pullup failed\n");
442 		sc->sc_pullup_ev.ev_count++;
443 		return;
444 	}
445 	gh = mtod(m, const struct gre_h *);
446 
447 	if (gre_input(sc, m, 0, gh) == 0) {
448 		sc->sc_unsupp_ev.ev_count++;
449 		GRE_DPRINTF(sc, "dropping unsupported\n");
450 		m_freem(m);
451 	}
452 }
453 
454 static void
455 gre_upcall_add(struct socket *so, void *arg)
456 {
457 	/* XXX What if the kernel already set an upcall? */
458 	KASSERT((so->so_rcv.sb_flags & SB_UPCALL) == 0);
459 	so->so_upcallarg = arg;
460 	so->so_upcall = gre_receive;
461 	so->so_rcv.sb_flags |= SB_UPCALL;
462 }
463 
464 static void
465 gre_upcall_remove(struct socket *so)
466 {
467 	so->so_rcv.sb_flags &= ~SB_UPCALL;
468 	so->so_upcallarg = NULL;
469 	so->so_upcall = NULL;
470 }
471 
472 static int
473 gre_socreate(struct gre_softc *sc, const struct gre_soparm *sp, int *fdout)
474 {
475 	const struct protosw *pr;
476 	int fd, rc;
477 	struct mbuf *m;
478 	struct sockaddr *sa;
479 	struct socket *so;
480 	sa_family_t af;
481 	int val;
482 
483 	GRE_DPRINTF(sc, "enter\n");
484 
485 	af = sp->sp_src.ss_family;
486 	rc = fsocreate(af, NULL, sp->sp_type, sp->sp_proto, curlwp, &fd);
487 	if (rc != 0) {
488 		GRE_DPRINTF(sc, "fsocreate failed\n");
489 		return rc;
490 	}
491 
492 	if ((rc = fd_getsock(fd, &so)) != 0)
493 		return rc;
494 
495 	if ((m = getsombuf(so, MT_SONAME)) == NULL) {
496 		rc = ENOBUFS;
497 		goto out;
498 	}
499 	sa = mtod(m, struct sockaddr *);
500 	sockaddr_copy(sa, MIN(MLEN, sizeof(sp->sp_src)), sstocsa(&sp->sp_src));
501 	m->m_len = sp->sp_src.ss_len;
502 
503 	if ((rc = sobind(so, m, curlwp)) != 0) {
504 		GRE_DPRINTF(sc, "sobind failed\n");
505 		goto out;
506 	}
507 
508 	sockaddr_copy(sa, MIN(MLEN, sizeof(sp->sp_dst)), sstocsa(&sp->sp_dst));
509 	m->m_len = sp->sp_dst.ss_len;
510 
511 	solock(so);
512 	if ((rc = soconnect(so, m, curlwp)) != 0) {
513 		GRE_DPRINTF(sc, "soconnect failed\n");
514 		sounlock(so);
515 		goto out;
516 	}
517 	sounlock(so);
518 
519 	m = NULL;
520 
521 	/* XXX convert to a (new) SOL_SOCKET call */
522   	pr = so->so_proto;
523   	KASSERT(pr != NULL);
524  	rc = so_setsockopt(curlwp, so, IPPROTO_IP, IP_TTL,
525 	    &ip_gre_ttl, sizeof(ip_gre_ttl));
526   	if (rc != 0) {
527  		GRE_DPRINTF(sc, "so_setsockopt ttl failed\n");
528   		rc = 0;
529   	}
530 
531  	val = 1;
532  	rc = so_setsockopt(curlwp, so, SOL_SOCKET, SO_NOHEADER,
533 	    &val, sizeof(val));
534   	if (rc != 0) {
535  		GRE_DPRINTF(sc, "so_setsockopt SO_NOHEADER failed\n");
536 		rc = 0;
537 	}
538 out:
539 	m_freem(m);
540 
541 	if (rc != 0)
542 		fd_close(fd);
543 	else  {
544 		fd_putfile(fd);
545 		*fdout = fd;
546 	}
547 
548 	return rc;
549 }
550 
551 static int
552 gre_sosend(struct socket *so, struct mbuf *top)
553 {
554 	struct mbuf	**mp;
555 	struct proc	*p;
556 	long		space, resid;
557 	int		error;
558 	struct lwp * const l = curlwp;
559 
560 	p = l->l_proc;
561 
562 	resid = top->m_pkthdr.len;
563 	if (p)
564 		l->l_ru.ru_msgsnd++;
565 #define	snderr(errno)	{ error = errno; goto release; }
566 
567 	solock(so);
568 	if ((error = sblock(&so->so_snd, M_NOWAIT)) != 0)
569 		goto out;
570 	if (so->so_state & SS_CANTSENDMORE)
571 		snderr(EPIPE);
572 	if (so->so_error) {
573 		error = so->so_error;
574 		so->so_error = 0;
575 		goto release;
576 	}
577 	if ((so->so_state & SS_ISCONNECTED) == 0) {
578 		if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
579 			if ((so->so_state & SS_ISCONFIRMING) == 0)
580 				snderr(ENOTCONN);
581 		} else
582 			snderr(EDESTADDRREQ);
583 	}
584 	space = sbspace(&so->so_snd);
585 	if (resid > so->so_snd.sb_hiwat)
586 		snderr(EMSGSIZE);
587 	if (space < resid)
588 		snderr(EWOULDBLOCK);
589 	mp = &top;
590 	/*
591 	 * Data is prepackaged in "top".
592 	 */
593 	if (so->so_state & SS_CANTSENDMORE)
594 		snderr(EPIPE);
595 	error = (*so->so_proto->pr_usrreq)(so, PRU_SEND, top, NULL, NULL, l);
596 	top = NULL;
597 	mp = &top;
598  release:
599 	sbunlock(&so->so_snd);
600  out:
601  	sounlock(so);
602 	if (top != NULL)
603 		m_freem(top);
604 	return error;
605 }
606 
607 /* This is a stripped-down version of soreceive() that will never
608  * block.  It will support SOCK_DGRAM sockets.  It may also support
609  * SOCK_SEQPACKET sockets.
610  */
611 static int
612 gre_soreceive(struct socket *so, struct mbuf **mp0)
613 {
614 	struct mbuf *m, **mp;
615 	int flags, len, error, type;
616 	const struct protosw	*pr;
617 	struct mbuf *nextrecord;
618 
619 	KASSERT(mp0 != NULL);
620 
621 	flags = MSG_DONTWAIT;
622 	pr = so->so_proto;
623 	mp = mp0;
624 	type = 0;
625 
626 	*mp = NULL;
627 
628 	KASSERT(pr->pr_flags & PR_ATOMIC);
629 
630 	if (so->so_state & SS_ISCONFIRMING)
631 		(*pr->pr_usrreq)(so, PRU_RCVD, NULL, NULL, NULL, curlwp);
632  restart:
633 	if ((error = sblock(&so->so_rcv, M_NOWAIT)) != 0) {
634 		return error;
635 	}
636 	m = so->so_rcv.sb_mb;
637 	/*
638 	 * If we have less data than requested, do not block awaiting more.
639 	 */
640 	if (m == NULL) {
641 #ifdef DIAGNOSTIC
642 		if (so->so_rcv.sb_cc)
643 			panic("receive 1");
644 #endif
645 		if (so->so_error) {
646 			error = so->so_error;
647 			so->so_error = 0;
648 		} else if (so->so_state & SS_CANTRCVMORE)
649 			;
650 		else if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0
651 		      && (so->so_proto->pr_flags & PR_CONNREQUIRED))
652 			error = ENOTCONN;
653 		else
654 			error = EWOULDBLOCK;
655 		goto release;
656 	}
657 	/*
658 	 * On entry here, m points to the first record of the socket buffer.
659 	 * While we process the initial mbufs containing address and control
660 	 * info, we save a copy of m->m_nextpkt into nextrecord.
661 	 */
662 	if (curlwp != NULL)
663 		curlwp->l_ru.ru_msgrcv++;
664 	KASSERT(m == so->so_rcv.sb_mb);
665 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 1");
666 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 1");
667 	nextrecord = m->m_nextpkt;
668 	if (pr->pr_flags & PR_ADDR) {
669 #ifdef DIAGNOSTIC
670 		if (m->m_type != MT_SONAME)
671 			panic("receive 1a");
672 #endif
673 		sbfree(&so->so_rcv, m);
674 		MFREE(m, so->so_rcv.sb_mb);
675 		m = so->so_rcv.sb_mb;
676 	}
677 	while (m != NULL && m->m_type == MT_CONTROL && error == 0) {
678 		sbfree(&so->so_rcv, m);
679 		/*
680 		 * Dispose of any SCM_RIGHTS message that went
681 		 * through the read path rather than recv.
682 		 */
683 		if (pr->pr_domain->dom_dispose &&
684 		    mtod(m, struct cmsghdr *)->cmsg_type == SCM_RIGHTS)
685 			(*pr->pr_domain->dom_dispose)(m);
686 		MFREE(m, so->so_rcv.sb_mb);
687 		m = so->so_rcv.sb_mb;
688 	}
689 
690 	/*
691 	 * If m is non-NULL, we have some data to read.  From now on,
692 	 * make sure to keep sb_lastrecord consistent when working on
693 	 * the last packet on the chain (nextrecord == NULL) and we
694 	 * change m->m_nextpkt.
695 	 */
696 	if (m != NULL) {
697 		m->m_nextpkt = nextrecord;
698 		/*
699 		 * If nextrecord == NULL (this is a single chain),
700 		 * then sb_lastrecord may not be valid here if m
701 		 * was changed earlier.
702 		 */
703 		if (nextrecord == NULL) {
704 			KASSERT(so->so_rcv.sb_mb == m);
705 			so->so_rcv.sb_lastrecord = m;
706 		}
707 		type = m->m_type;
708 		if (type == MT_OOBDATA)
709 			flags |= MSG_OOB;
710 	} else {
711 		KASSERT(so->so_rcv.sb_mb == m);
712 		so->so_rcv.sb_mb = nextrecord;
713 		SB_EMPTY_FIXUP(&so->so_rcv);
714 	}
715 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 2");
716 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 2");
717 
718 	while (m != NULL) {
719 		if (m->m_type == MT_OOBDATA) {
720 			if (type != MT_OOBDATA)
721 				break;
722 		} else if (type == MT_OOBDATA)
723 			break;
724 #ifdef DIAGNOSTIC
725 		else if (m->m_type != MT_DATA && m->m_type != MT_HEADER)
726 			panic("receive 3");
727 #endif
728 		so->so_state &= ~SS_RCVATMARK;
729 		if (so->so_oobmark != 0 && so->so_oobmark < m->m_len)
730 			break;
731 		len = m->m_len;
732 		/*
733 		 * mp is set, just pass back the mbufs.
734 		 * Sockbuf must be consistent here (points to current mbuf,
735 		 * it points to next record) when we drop priority;
736 		 * we must note any additions to the sockbuf when we
737 		 * block interrupts again.
738 		 */
739 		if (m->m_flags & M_EOR)
740 			flags |= MSG_EOR;
741 		nextrecord = m->m_nextpkt;
742 		sbfree(&so->so_rcv, m);
743 		*mp = m;
744 		mp = &m->m_next;
745 		so->so_rcv.sb_mb = m = m->m_next;
746 		*mp = NULL;
747 		/*
748 		 * If m != NULL, we also know that
749 		 * so->so_rcv.sb_mb != NULL.
750 		 */
751 		KASSERT(so->so_rcv.sb_mb == m);
752 		if (m) {
753 			m->m_nextpkt = nextrecord;
754 			if (nextrecord == NULL)
755 				so->so_rcv.sb_lastrecord = m;
756 		} else {
757 			so->so_rcv.sb_mb = nextrecord;
758 			SB_EMPTY_FIXUP(&so->so_rcv);
759 		}
760 		SBLASTRECORDCHK(&so->so_rcv, "soreceive 3");
761 		SBLASTMBUFCHK(&so->so_rcv, "soreceive 3");
762 		if (so->so_oobmark) {
763 			so->so_oobmark -= len;
764 			if (so->so_oobmark == 0) {
765 				so->so_state |= SS_RCVATMARK;
766 				break;
767 			}
768 		}
769 		if (flags & MSG_EOR)
770 			break;
771 	}
772 
773 	if (m != NULL) {
774 		m_freem(*mp);
775 		*mp = NULL;
776 		error = ENOMEM;
777 		(void) sbdroprecord(&so->so_rcv);
778 	} else {
779 		/*
780 		 * First part is an inline SB_EMPTY_FIXUP().  Second
781 		 * part makes sure sb_lastrecord is up-to-date if
782 		 * there is still data in the socket buffer.
783 		 */
784 		so->so_rcv.sb_mb = nextrecord;
785 		if (so->so_rcv.sb_mb == NULL) {
786 			so->so_rcv.sb_mbtail = NULL;
787 			so->so_rcv.sb_lastrecord = NULL;
788 		} else if (nextrecord->m_nextpkt == NULL)
789 			so->so_rcv.sb_lastrecord = nextrecord;
790 	}
791 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 4");
792 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 4");
793 	if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
794 		(*pr->pr_usrreq)(so, PRU_RCVD, NULL,
795 		    (struct mbuf *)(long)flags, NULL, curlwp);
796 	if (*mp0 == NULL && (flags & MSG_EOR) == 0 &&
797 	    (so->so_state & SS_CANTRCVMORE) == 0) {
798 		sbunlock(&so->so_rcv);
799 		goto restart;
800 	}
801 
802  release:
803 	sbunlock(&so->so_rcv);
804 	return error;
805 }
806 
807 static struct socket *
808 gre_reconf(struct gre_softc *sc, const struct gre_soparm *newsoparm)
809 {
810 	struct ifnet *ifp = &sc->sc_if;
811 
812 	GRE_DPRINTF(sc, "enter\n");
813 
814 shutdown:
815 	if (sc->sc_soparm.sp_so != NULL) {
816 		GRE_DPRINTF(sc, "\n");
817 		gre_upcall_remove(sc->sc_soparm.sp_so);
818 		softint_disestablish(sc->sc_si);
819 		sc->sc_si = NULL;
820 		gre_fp_send(sc, GRE_M_DELFP, NULL);
821 		gre_clearconf(&sc->sc_soparm, false);
822 	}
823 
824 	if (newsoparm != NULL) {
825 		GRE_DPRINTF(sc, "\n");
826 		sc->sc_soparm = *newsoparm;
827 		newsoparm = NULL;
828 	}
829 
830 	if (sc->sc_soparm.sp_so != NULL) {
831 		GRE_DPRINTF(sc, "\n");
832 		sc->sc_si = softint_establish(SOFTINT_NET, greintr, sc);
833 		gre_upcall_add(sc->sc_soparm.sp_so, sc);
834 		if ((ifp->if_flags & IFF_UP) == 0) {
835 			GRE_DPRINTF(sc, "down\n");
836 			goto shutdown;
837 		}
838 	}
839 
840 	GRE_DPRINTF(sc, "\n");
841 	if (sc->sc_soparm.sp_so != NULL)
842 		sc->sc_if.if_flags |= IFF_RUNNING;
843 	else {
844 		gre_bufq_purge(&sc->sc_snd);
845 		sc->sc_if.if_flags &= ~IFF_RUNNING;
846 	}
847 	return sc->sc_soparm.sp_so;
848 }
849 
850 static int
851 gre_input(struct gre_softc *sc, struct mbuf *m, int hlen,
852     const struct gre_h *gh)
853 {
854 	uint16_t flags;
855 	uint32_t af;		/* af passed to BPF tap */
856 	int isr, s;
857 	struct ifqueue *ifq;
858 
859 	sc->sc_if.if_ipackets++;
860 	sc->sc_if.if_ibytes += m->m_pkthdr.len;
861 
862 	hlen += sizeof(struct gre_h);
863 
864 	/* process GRE flags as packet can be of variable len */
865 	flags = ntohs(gh->flags);
866 
867 	/* Checksum & Offset are present */
868 	if ((flags & GRE_CP) | (flags & GRE_RP))
869 		hlen += 4;
870 	/* We don't support routing fields (variable length) */
871 	if (flags & GRE_RP) {
872 		sc->sc_if.if_ierrors++;
873 		return 0;
874 	}
875 	if (flags & GRE_KP)
876 		hlen += 4;
877 	if (flags & GRE_SP)
878 		hlen += 4;
879 
880 	switch (ntohs(gh->ptype)) { /* ethertypes */
881 #ifdef INET
882 	case ETHERTYPE_IP:
883 		ifq = &ipintrq;
884 		isr = NETISR_IP;
885 		af = AF_INET;
886 		break;
887 #endif
888 #ifdef NETATALK
889 	case ETHERTYPE_ATALK:
890 		ifq = &atintrq1;
891 		isr = NETISR_ATALK;
892 		af = AF_APPLETALK;
893 		break;
894 #endif
895 #ifdef INET6
896 	case ETHERTYPE_IPV6:
897 		ifq = &ip6intrq;
898 		isr = NETISR_IPV6;
899 		af = AF_INET6;
900 		break;
901 #endif
902 	default:	   /* others not yet supported */
903 		GRE_DPRINTF(sc, "unhandled ethertype 0x%04x\n",
904 		    ntohs(gh->ptype));
905 		sc->sc_if.if_noproto++;
906 		return 0;
907 	}
908 
909 	if (hlen > m->m_pkthdr.len) {
910 		m_freem(m);
911 		sc->sc_if.if_ierrors++;
912 		return EINVAL;
913 	}
914 	m_adj(m, hlen);
915 
916 	bpf_mtap_af(&sc->sc_if, af, m);
917 
918 	m->m_pkthdr.rcvif = &sc->sc_if;
919 
920 	s = splnet();
921 	if (IF_QFULL(ifq)) {
922 		IF_DROP(ifq);
923 		m_freem(m);
924 	} else {
925 		IF_ENQUEUE(ifq, m);
926 	}
927 	/* we need schednetisr since the address family may change */
928 	schednetisr(isr);
929 	splx(s);
930 
931 	return 1;	/* packet is done, no further processing needed */
932 }
933 
934 /*
935  * The output routine. Takes a packet and encapsulates it in the protocol
936  * given by sc->sc_soparm.sp_proto. See also RFC 1701 and RFC 2004
937  */
938 static int
939 gre_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
940 	   struct rtentry *rt)
941 {
942 	int error = 0;
943 	struct gre_softc *sc = ifp->if_softc;
944 	struct gre_h *gh;
945 	uint16_t etype = 0;
946 
947 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) {
948 		m_freem(m);
949 		error = ENETDOWN;
950 		goto end;
951 	}
952 
953 	bpf_mtap_af(ifp, dst->sa_family, m);
954 
955 	m->m_flags &= ~(M_BCAST|M_MCAST);
956 
957 	GRE_DPRINTF(sc, "dst->sa_family=%d\n", dst->sa_family);
958 	switch (dst->sa_family) {
959 #ifdef INET
960 	case AF_INET:
961 		/* TBD Extract the IP ToS field and set the
962 		 * encapsulating protocol's ToS to suit.
963 		 */
964 		etype = htons(ETHERTYPE_IP);
965 		break;
966 #endif
967 #ifdef NETATALK
968 	case AF_APPLETALK:
969 		etype = htons(ETHERTYPE_ATALK);
970 		break;
971 #endif
972 #ifdef INET6
973 	case AF_INET6:
974 		etype = htons(ETHERTYPE_IPV6);
975 		break;
976 #endif
977 	default:
978 		IF_DROP(&ifp->if_snd);
979 		m_freem(m);
980 		error = EAFNOSUPPORT;
981 		goto end;
982 	}
983 
984 	M_PREPEND(m, sizeof(*gh), M_DONTWAIT);
985 
986 	if (m == NULL) {
987 		IF_DROP(&ifp->if_snd);
988 		error = ENOBUFS;
989 		goto end;
990 	}
991 
992 	gh = mtod(m, struct gre_h *);
993 	gh->flags = 0;
994 	gh->ptype = etype;
995 	/* XXX Need to handle IP ToS.  Look at how I handle IP TTL. */
996 
997 	ifp->if_opackets++;
998 	ifp->if_obytes += m->m_pkthdr.len;
999 
1000 	/* send it off */
1001 	if ((error = gre_bufq_enqueue(&sc->sc_snd, m)) != 0) {
1002 		sc->sc_oflow_ev.ev_count++;
1003 		m_freem(m);
1004 	} else
1005 		softint_schedule(sc->sc_si);
1006   end:
1007 	if (error)
1008 		ifp->if_oerrors++;
1009 	return error;
1010 }
1011 
1012 static int
1013 gre_getname(struct socket *so, int req, struct mbuf *nam, struct lwp *l)
1014 {
1015 	return (*so->so_proto->pr_usrreq)(so, req, NULL, nam, NULL, l);
1016 }
1017 
1018 static int
1019 gre_getsockname(struct socket *so, struct mbuf *nam, struct lwp *l)
1020 {
1021 	return gre_getname(so, PRU_SOCKADDR, nam, l);
1022 }
1023 
1024 static int
1025 gre_getpeername(struct socket *so, struct mbuf *nam, struct lwp *l)
1026 {
1027 	return gre_getname(so, PRU_PEERADDR, nam, l);
1028 }
1029 
1030 static int
1031 gre_getnames(struct socket *so, struct lwp *l, struct sockaddr_storage *src,
1032     struct sockaddr_storage *dst)
1033 {
1034 	struct mbuf *m;
1035 	struct sockaddr_storage *ss;
1036 	int rc;
1037 
1038 	if ((m = getsombuf(so, MT_SONAME)) == NULL)
1039 		return ENOBUFS;
1040 
1041 	ss = mtod(m, struct sockaddr_storage *);
1042 
1043 	solock(so);
1044 	if ((rc = gre_getsockname(so, m, l)) != 0)
1045 		goto out;
1046 	*src = *ss;
1047 
1048 	if ((rc = gre_getpeername(so, m, l)) != 0)
1049 		goto out;
1050 	*dst = *ss;
1051 out:
1052 	sounlock(so);
1053 	m_freem(m);
1054 	return rc;
1055 }
1056 
1057 static void
1058 gre_fp_recvloop(void *arg)
1059 {
1060 	struct gre_softc *sc = arg;
1061 
1062 	mutex_enter(&sc->sc_mtx);
1063 	while (gre_fp_recv(sc))
1064 		;
1065 	mutex_exit(&sc->sc_mtx);
1066 	kthread_exit(0);
1067 }
1068 
1069 static bool
1070 gre_fp_recv(struct gre_softc *sc)
1071 {
1072 	int fd, ofd, rc;
1073 	file_t *fp;
1074 
1075 	fp = sc->sc_fp;
1076 	ofd = sc->sc_fd;
1077 	fd = -1;
1078 
1079 	switch (sc->sc_msg) {
1080 	case GRE_M_STOP:
1081 		cv_signal(&sc->sc_fp_condvar);
1082 		return false;
1083 	case GRE_M_SETFP:
1084 		mutex_exit(&sc->sc_mtx);
1085 		rc = fd_dup(fp, 0, &fd, 0);
1086 		mutex_enter(&sc->sc_mtx);
1087 		if (rc != 0) {
1088 			sc->sc_msg = GRE_M_ERR;
1089 			break;
1090 		}
1091 		/*FALLTHROUGH*/
1092 	case GRE_M_DELFP:
1093 		mutex_exit(&sc->sc_mtx);
1094 		if (ofd != -1 && fd_getfile(ofd) != NULL)
1095 			fd_close(ofd);
1096 		mutex_enter(&sc->sc_mtx);
1097 		sc->sc_fd = fd;
1098 		sc->sc_msg = GRE_M_OK;
1099 		break;
1100 	default:
1101 		gre_fp_wait(sc);
1102 		return true;
1103 	}
1104 	cv_signal(&sc->sc_fp_condvar);
1105 	return true;
1106 }
1107 
1108 static bool
1109 gre_fp_send(struct gre_softc *sc, enum gre_msg msg, file_t *fp)
1110 {
1111 	bool rc;
1112 
1113 	mutex_enter(&sc->sc_mtx);
1114 	while (sc->sc_msg != GRE_M_NONE)
1115 		gre_fp_wait(sc);
1116 	sc->sc_fp = fp;
1117 	sc->sc_msg = msg;
1118 	cv_signal(&sc->sc_fp_condvar);
1119 	while (sc->sc_msg != GRE_M_STOP && sc->sc_msg != GRE_M_OK &&
1120 	            sc->sc_msg != GRE_M_ERR)
1121 		gre_fp_wait(sc);
1122 	rc = (sc->sc_msg != GRE_M_ERR);
1123 	sc->sc_msg = GRE_M_NONE;
1124 	cv_signal(&sc->sc_fp_condvar);
1125 	mutex_exit(&sc->sc_mtx);
1126 	return rc;
1127 }
1128 
1129 static int
1130 gre_ssock(struct ifnet *ifp, struct gre_soparm *sp, int fd)
1131 {
1132 	int error = 0;
1133 	const struct protosw *pr;
1134 	file_t *fp;
1135 	struct gre_softc *sc = ifp->if_softc;
1136 	struct socket *so;
1137 	struct sockaddr_storage dst, src;
1138 
1139 	if ((fp = fd_getfile(fd)) == NULL)
1140 		return EBADF;
1141 	if (fp->f_type != DTYPE_SOCKET) {
1142 		fd_putfile(fd);
1143 		return ENOTSOCK;
1144 	}
1145 
1146 	GRE_DPRINTF(sc, "\n");
1147 
1148 	so = (struct socket *)fp->f_data;
1149 	pr = so->so_proto;
1150 
1151 	GRE_DPRINTF(sc, "type %d, proto %d\n", pr->pr_type, pr->pr_protocol);
1152 
1153 	if ((pr->pr_flags & PR_ATOMIC) == 0 ||
1154 	    (sp->sp_type != 0 && pr->pr_type != sp->sp_type) ||
1155 	    (sp->sp_proto != 0 && pr->pr_protocol != 0 &&
1156 	     pr->pr_protocol != sp->sp_proto)) {
1157 		error = EINVAL;
1158 		goto err;
1159 	}
1160 
1161 	GRE_DPRINTF(sc, "\n");
1162 
1163 	/* check address */
1164 	if ((error = gre_getnames(so, curlwp, &src, &dst)) != 0)
1165 		goto err;
1166 
1167 	GRE_DPRINTF(sc, "\n");
1168 
1169 	if (!gre_fp_send(sc, GRE_M_SETFP, fp)) {
1170 		error = EBUSY;
1171 		goto err;
1172 	}
1173 
1174 	GRE_DPRINTF(sc, "\n");
1175 
1176 	sp->sp_src = src;
1177 	sp->sp_dst = dst;
1178 
1179 	sp->sp_so = so;
1180 
1181 err:
1182 	fd_putfile(fd);
1183 	return error;
1184 }
1185 
1186 static bool
1187 sockaddr_is_anyaddr(const struct sockaddr *sa)
1188 {
1189 	socklen_t anylen, salen;
1190 	const void *anyaddr, *addr;
1191 
1192 	if ((anyaddr = sockaddr_anyaddr(sa, &anylen)) == NULL ||
1193 	    (addr = sockaddr_const_addr(sa, &salen)) == NULL)
1194 		return false;
1195 
1196 	if (salen > anylen)
1197 		return false;
1198 
1199 	return memcmp(anyaddr, addr, MIN(anylen, salen)) == 0;
1200 }
1201 
1202 static bool
1203 gre_is_nullconf(const struct gre_soparm *sp)
1204 {
1205 	return sockaddr_is_anyaddr(sstocsa(&sp->sp_src)) ||
1206 	       sockaddr_is_anyaddr(sstocsa(&sp->sp_dst));
1207 }
1208 
1209 static void
1210 gre_clearconf(struct gre_soparm *sp, bool force)
1211 {
1212 	if (sp->sp_bysock || force) {
1213 		sockaddr_copy(sstosa(&sp->sp_src), sizeof(sp->sp_src),
1214 		    sockaddr_any(sstosa(&sp->sp_src)));
1215 		sockaddr_copy(sstosa(&sp->sp_dst), sizeof(sp->sp_dst),
1216 		    sockaddr_any(sstosa(&sp->sp_dst)));
1217 		sp->sp_bysock = false;
1218 	}
1219 	sp->sp_so = NULL; /* XXX */
1220 }
1221 
1222 static int
1223 gre_ioctl_lock(struct gre_softc *sc)
1224 {
1225 	mutex_enter(&sc->sc_mtx);
1226 
1227 	while (sc->sc_state == GRE_S_IOCTL)
1228 		gre_wait(sc);
1229 
1230 	if (sc->sc_state != GRE_S_IDLE) {
1231 		cv_signal(&sc->sc_condvar);
1232 		mutex_exit(&sc->sc_mtx);
1233 		GRE_DPRINTF(sc, "\n");
1234 		return ENXIO;
1235 	}
1236 
1237 	sc->sc_state = GRE_S_IOCTL;
1238 
1239 	mutex_exit(&sc->sc_mtx);
1240 	return 0;
1241 }
1242 
1243 static void
1244 gre_ioctl_unlock(struct gre_softc *sc)
1245 {
1246 	mutex_enter(&sc->sc_mtx);
1247 
1248 	KASSERT(sc->sc_state == GRE_S_IOCTL);
1249 	sc->sc_state = GRE_S_IDLE;
1250 	cv_signal(&sc->sc_condvar);
1251 
1252 	mutex_exit(&sc->sc_mtx);
1253 }
1254 
1255 static int
1256 gre_ioctl(struct ifnet *ifp, const u_long cmd, void *data)
1257 {
1258 	struct ifreq *ifr;
1259 	struct if_laddrreq *lifr = (struct if_laddrreq *)data;
1260 	struct gre_softc *sc = ifp->if_softc;
1261 	struct gre_soparm *sp;
1262 	int fd, error = 0, oproto, otype, s;
1263 	struct gre_soparm sp0;
1264 
1265 	ifr = data;
1266 
1267 	GRE_DPRINTF(sc, "cmd %lu\n", cmd);
1268 
1269 	switch (cmd) {
1270 	case SIOCSIFFLAGS:
1271 	case SIOCSIFMTU:
1272 	case GRESPROTO:
1273 	case GRESADDRD:
1274 	case GRESADDRS:
1275 	case GRESSOCK:
1276 	case GREDSOCK:
1277 	case SIOCSLIFPHYADDR:
1278 	case SIOCDIFPHYADDR:
1279 		if (kauth_authorize_network(curlwp->l_cred,
1280 		    KAUTH_NETWORK_INTERFACE,
1281 		    KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
1282 		    NULL) != 0)
1283 			return EPERM;
1284 		break;
1285 	default:
1286 		break;
1287 	}
1288 
1289 	if ((error = gre_ioctl_lock(sc)) != 0) {
1290 		GRE_DPRINTF(sc, "\n");
1291 		return error;
1292 	}
1293 	s = splnet();
1294 
1295 	sp0 = sc->sc_soparm;
1296 	sp0.sp_so = NULL;
1297 	sp = &sp0;
1298 
1299 	GRE_DPRINTF(sc, "\n");
1300 
1301 	switch (cmd) {
1302 	case SIOCINITIFADDR:
1303 		GRE_DPRINTF(sc, "\n");
1304 		if ((ifp->if_flags & IFF_UP) != 0)
1305 			break;
1306 		gre_clearconf(sp, false);
1307 		ifp->if_flags |= IFF_UP;
1308 		goto mksocket;
1309 	case SIOCSIFDSTADDR:
1310 		break;
1311 	case SIOCSIFFLAGS:
1312 		if ((error = ifioctl_common(ifp, cmd, data)) != 0)
1313 			break;
1314 		oproto = sp->sp_proto;
1315 		otype = sp->sp_type;
1316 		switch (ifr->ifr_flags & (IFF_LINK0|IFF_LINK2)) {
1317 		case IFF_LINK0|IFF_LINK2:
1318 			sp->sp_proto = IPPROTO_UDP;
1319 			sp->sp_type = SOCK_DGRAM;
1320 			break;
1321 		case IFF_LINK2:
1322 			sp->sp_proto = 0;
1323 			sp->sp_type = 0;
1324 			break;
1325 		case IFF_LINK0:
1326 			sp->sp_proto = IPPROTO_GRE;
1327 			sp->sp_type = SOCK_RAW;
1328 			break;
1329 		default:
1330 			GRE_DPRINTF(sc, "\n");
1331 			error = EINVAL;
1332 			goto out;
1333 		}
1334 		GRE_DPRINTF(sc, "\n");
1335 		gre_clearconf(sp, false);
1336 		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) ==
1337 		    (IFF_UP|IFF_RUNNING) &&
1338 		    (oproto == sp->sp_proto || sp->sp_proto == 0) &&
1339 		    (otype == sp->sp_type || sp->sp_type == 0))
1340 			break;
1341 		switch (sp->sp_proto) {
1342 		case IPPROTO_UDP:
1343 		case IPPROTO_GRE:
1344 			goto mksocket;
1345 		default:
1346 			break;
1347 		}
1348 		break;
1349 	case SIOCSIFMTU:
1350 		/* XXX determine MTU automatically by probing w/
1351 		 * XXX do-not-fragment packets?
1352 		 */
1353 		if (ifr->ifr_mtu < 576) {
1354 			error = EINVAL;
1355 			break;
1356 		}
1357 		/*FALLTHROUGH*/
1358 	case SIOCGIFMTU:
1359 		if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET)
1360 			error = 0;
1361 		break;
1362 	case SIOCADDMULTI:
1363 	case SIOCDELMULTI:
1364 		if (ifr == NULL) {
1365 			error = EAFNOSUPPORT;
1366 			break;
1367 		}
1368 		switch (ifreq_getaddr(cmd, ifr)->sa_family) {
1369 #ifdef INET
1370 		case AF_INET:
1371 			break;
1372 #endif
1373 #ifdef INET6
1374 		case AF_INET6:
1375 			break;
1376 #endif
1377 		default:
1378 			error = EAFNOSUPPORT;
1379 			break;
1380 		}
1381 		break;
1382 	case GRESPROTO:
1383 		gre_clearconf(sp, false);
1384 		oproto = sp->sp_proto;
1385 		otype = sp->sp_type;
1386 		sp->sp_proto = ifr->ifr_flags;
1387 		switch (sp->sp_proto) {
1388 		case IPPROTO_UDP:
1389 			ifp->if_flags |= IFF_LINK0|IFF_LINK2;
1390 			sp->sp_type = SOCK_DGRAM;
1391 			break;
1392 		case IPPROTO_GRE:
1393 			ifp->if_flags |= IFF_LINK0;
1394 			ifp->if_flags &= ~IFF_LINK2;
1395 			sp->sp_type = SOCK_RAW;
1396 			break;
1397 		case 0:
1398 			ifp->if_flags &= ~IFF_LINK0;
1399 			ifp->if_flags |= IFF_LINK2;
1400 			sp->sp_type = 0;
1401 			break;
1402 		default:
1403 			error = EPROTONOSUPPORT;
1404 			break;
1405 		}
1406 		if ((oproto == sp->sp_proto || sp->sp_proto == 0) &&
1407 		    (otype == sp->sp_type || sp->sp_type == 0))
1408 			break;
1409 		switch (sp->sp_proto) {
1410 		case IPPROTO_UDP:
1411 		case IPPROTO_GRE:
1412 			goto mksocket;
1413 		default:
1414 			break;
1415 		}
1416 		break;
1417 	case GREGPROTO:
1418 		ifr->ifr_flags = sp->sp_proto;
1419 		break;
1420 	case GRESADDRS:
1421 	case GRESADDRD:
1422 		gre_clearconf(sp, false);
1423 		/* set tunnel endpoints and mark interface as up */
1424 		switch (cmd) {
1425 		case GRESADDRS:
1426 			sockaddr_copy(sstosa(&sp->sp_src),
1427 			    sizeof(sp->sp_src), ifreq_getaddr(cmd, ifr));
1428 			break;
1429 		case GRESADDRD:
1430 			sockaddr_copy(sstosa(&sp->sp_dst),
1431 			    sizeof(sp->sp_dst), ifreq_getaddr(cmd, ifr));
1432 			break;
1433 		}
1434 	checkaddr:
1435 		if (sockaddr_any(sstosa(&sp->sp_src)) == NULL ||
1436 		    sockaddr_any(sstosa(&sp->sp_dst)) == NULL) {
1437 			error = EINVAL;
1438 			break;
1439 		}
1440 		/* let gre_socreate() check the rest */
1441 	mksocket:
1442 		GRE_DPRINTF(sc, "\n");
1443 		/* If we're administratively down, or the configuration
1444 		 * is empty, there's no use creating a socket.
1445 		 */
1446 		if ((ifp->if_flags & IFF_UP) == 0 || gre_is_nullconf(sp))
1447 			goto sendconf;
1448 
1449 		GRE_DPRINTF(sc, "\n");
1450 		fd = 0;
1451 		error = gre_socreate(sc, sp, &fd);
1452 		if (error != 0)
1453 			break;
1454 
1455 	setsock:
1456 		GRE_DPRINTF(sc, "\n");
1457 
1458 		error = gre_ssock(ifp, sp, fd);
1459 
1460 		if (cmd != GRESSOCK) {
1461 			GRE_DPRINTF(sc, "\n");
1462 			/* XXX v. dodgy */
1463 			if (fd_getfile(fd) != NULL)
1464 				fd_close(fd);
1465 		}
1466 
1467 		if (error == 0) {
1468 	sendconf:
1469 			GRE_DPRINTF(sc, "\n");
1470 			ifp->if_flags &= ~IFF_RUNNING;
1471 			gre_reconf(sc, sp);
1472 		}
1473 
1474 		break;
1475 	case GREGADDRS:
1476 		ifreq_setaddr(cmd, ifr, sstosa(&sp->sp_src));
1477 		break;
1478 	case GREGADDRD:
1479 		ifreq_setaddr(cmd, ifr, sstosa(&sp->sp_dst));
1480 		break;
1481 	case GREDSOCK:
1482 		GRE_DPRINTF(sc, "\n");
1483 		if (sp->sp_bysock)
1484 			ifp->if_flags &= ~IFF_UP;
1485 		gre_clearconf(sp, false);
1486 		goto mksocket;
1487 	case GRESSOCK:
1488 		GRE_DPRINTF(sc, "\n");
1489 		gre_clearconf(sp, true);
1490 		fd = (int)ifr->ifr_value;
1491 		sp->sp_bysock = true;
1492 		ifp->if_flags |= IFF_UP;
1493 		goto setsock;
1494 	case SIOCSLIFPHYADDR:
1495 		GRE_DPRINTF(sc, "\n");
1496 		if (lifr->addr.ss_family != lifr->dstaddr.ss_family) {
1497 			error = EAFNOSUPPORT;
1498 			break;
1499 		}
1500 		sockaddr_copy(sstosa(&sp->sp_src), sizeof(sp->sp_src),
1501 		    sstosa(&lifr->addr));
1502 		sockaddr_copy(sstosa(&sp->sp_dst), sizeof(sp->sp_dst),
1503 		    sstosa(&lifr->dstaddr));
1504 		GRE_DPRINTF(sc, "\n");
1505 		goto checkaddr;
1506 	case SIOCDIFPHYADDR:
1507 		GRE_DPRINTF(sc, "\n");
1508 		gre_clearconf(sp, true);
1509 		ifp->if_flags &= ~IFF_UP;
1510 		goto mksocket;
1511 	case SIOCGLIFPHYADDR:
1512 		GRE_DPRINTF(sc, "\n");
1513 		if (gre_is_nullconf(sp)) {
1514 			error = EADDRNOTAVAIL;
1515 			break;
1516 		}
1517 		sockaddr_copy(sstosa(&lifr->addr), sizeof(lifr->addr),
1518 		    sstosa(&sp->sp_src));
1519 		sockaddr_copy(sstosa(&lifr->dstaddr), sizeof(lifr->dstaddr),
1520 		    sstosa(&sp->sp_dst));
1521 		GRE_DPRINTF(sc, "\n");
1522 		break;
1523 	default:
1524 		error = ifioctl_common(ifp, cmd, data);
1525 		break;
1526 	}
1527 out:
1528 	GRE_DPRINTF(sc, "\n");
1529 	splx(s);
1530 	gre_ioctl_unlock(sc);
1531 	return error;
1532 }
1533 
1534 void	greattach(int);
1535 
1536 /* ARGSUSED */
1537 void
1538 greattach(int count)
1539 {
1540 	if_clone_attach(&gre_cloner);
1541 }
1542