xref: /netbsd-src/sys/net/if_gre.c (revision 975a152cfcdb39ae6e496af647af0c7275ca0b61)
1 /*	$NetBSD: if_gre.c,v 1.151 2013/08/29 17:49:21 rmind 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 1.151 2013/08/29 17:49:21 rmind Exp $");
49 
50 #include "opt_atalk.h"
51 #include "opt_gre.h"
52 #include "opt_inet.h"
53 #include "opt_mpls.h"
54 
55 #include <sys/param.h>
56 #include <sys/file.h>
57 #include <sys/filedesc.h>
58 #include <sys/malloc.h>
59 #include <sys/mallocvar.h>
60 #include <sys/mbuf.h>
61 #include <sys/proc.h>
62 #include <sys/domain.h>
63 #include <sys/protosw.h>
64 #include <sys/socket.h>
65 #include <sys/socketvar.h>
66 #include <sys/ioctl.h>
67 #include <sys/queue.h>
68 #include <sys/intr.h>
69 #include <sys/systm.h>
70 #include <sys/sysctl.h>
71 #include <sys/kauth.h>
72 
73 #include <sys/kernel.h>
74 #include <sys/mutex.h>
75 #include <sys/condvar.h>
76 #include <sys/kthread.h>
77 
78 #include <sys/cpu.h>
79 
80 #include <net/ethertypes.h>
81 #include <net/if.h>
82 #include <net/if_types.h>
83 #include <net/netisr.h>
84 #include <net/route.h>
85 
86 #include <netinet/in_systm.h>
87 #include <netinet/in.h>
88 #include <netinet/ip.h> /* we always need this for sizeof(struct ip) */
89 
90 #ifdef INET
91 #include <netinet/in_var.h>
92 #include <netinet/ip_var.h>
93 #endif
94 
95 #ifdef INET6
96 #include <netinet6/in6_var.h>
97 #endif
98 
99 #ifdef MPLS
100 #include <netmpls/mpls.h>
101 #include <netmpls/mpls_var.h>
102 #endif
103 
104 #ifdef NETATALK
105 #include <netatalk/at.h>
106 #include <netatalk/at_var.h>
107 #include <netatalk/at_extern.h>
108 #endif
109 
110 #include <sys/time.h>
111 #include <net/bpf.h>
112 
113 #include <net/if_gre.h>
114 
115 #include <compat/sys/socket.h>
116 #include <compat/sys/sockio.h>
117 /*
118  * It is not easy to calculate the right value for a GRE MTU.
119  * We leave this task to the admin and use the same default that
120  * other vendors use.
121  */
122 #define GREMTU 1476
123 
124 #ifdef GRE_DEBUG
125 int gre_debug = 0;
126 #define	GRE_DPRINTF(__sc, ...)						\
127 	do {								\
128 		if (__predict_false(gre_debug ||			\
129 		    ((__sc)->sc_if.if_flags & IFF_DEBUG) != 0)) {	\
130 			printf("%s.%d: ", __func__, __LINE__);		\
131 			printf(__VA_ARGS__);				\
132 		}							\
133 	} while (/*CONSTCOND*/0)
134 #else
135 #define	GRE_DPRINTF(__sc, __fmt, ...)	do { } while (/*CONSTCOND*/0)
136 #endif /* GRE_DEBUG */
137 
138 int ip_gre_ttl = GRE_TTL;
139 
140 static int gre_clone_create(struct if_clone *, int);
141 static int gre_clone_destroy(struct ifnet *);
142 
143 static struct if_clone gre_cloner =
144     IF_CLONE_INITIALIZER("gre", gre_clone_create, gre_clone_destroy);
145 
146 static int gre_input(struct gre_softc *, struct mbuf *, int,
147     const struct gre_h *);
148 static bool gre_is_nullconf(const struct gre_soparm *);
149 static int gre_output(struct ifnet *, struct mbuf *,
150 			   const struct sockaddr *, struct rtentry *);
151 static int gre_ioctl(struct ifnet *, u_long, void *);
152 static int gre_getsockname(struct socket *, struct mbuf *, struct lwp *);
153 static int gre_getpeername(struct socket *, struct mbuf *, struct lwp *);
154 static int gre_getnames(struct socket *, struct lwp *,
155     struct sockaddr_storage *, struct sockaddr_storage *);
156 static void gre_clearconf(struct gre_soparm *, bool);
157 static int gre_soreceive(struct socket *, struct mbuf **);
158 static int gre_sosend(struct socket *, struct mbuf *);
159 static struct socket *gre_reconf(struct gre_softc *, const struct gre_soparm *);
160 
161 static bool gre_fp_send(struct gre_softc *, enum gre_msg, file_t *);
162 static bool gre_fp_recv(struct gre_softc *);
163 static void gre_fp_recvloop(void *);
164 
165 static void
166 gre_bufq_init(struct gre_bufq *bq, size_t len0)
167 {
168 	memset(bq, 0, sizeof(*bq));
169 	bq->bq_q = pcq_create(len0, KM_SLEEP);
170 	KASSERT(bq->bq_q != NULL);
171 }
172 
173 static struct mbuf *
174 gre_bufq_dequeue(struct gre_bufq *bq)
175 {
176 	return pcq_get(bq->bq_q);
177 }
178 
179 static void
180 gre_bufq_purge(struct gre_bufq *bq)
181 {
182 	struct mbuf *m;
183 
184 	while ((m = gre_bufq_dequeue(bq)) != NULL)
185 		m_freem(m);
186 }
187 
188 static void
189 gre_bufq_destroy(struct gre_bufq *bq)
190 {
191 	gre_bufq_purge(bq);
192 	pcq_destroy(bq->bq_q);
193 }
194 
195 static int
196 gre_bufq_enqueue(struct gre_bufq *bq, struct mbuf *m)
197 {
198 	KASSERT(bq->bq_q != NULL);
199 
200 	if (!pcq_put(bq->bq_q, m)) {
201 		bq->bq_drops++;
202 		return ENOBUFS;
203 	}
204 	return 0;
205 }
206 
207 static void
208 greintr(void *arg)
209 {
210 	struct gre_softc *sc = (struct gre_softc *)arg;
211 	struct socket *so = sc->sc_soparm.sp_so;
212 	int rc;
213 	struct mbuf *m;
214 
215 	KASSERT(so != NULL);
216 
217 	sc->sc_send_ev.ev_count++;
218 	GRE_DPRINTF(sc, "enter\n");
219 	while ((m = gre_bufq_dequeue(&sc->sc_snd)) != NULL) {
220 		/* XXX handle ENOBUFS? */
221 		if ((rc = gre_sosend(so, m)) != 0)
222 			GRE_DPRINTF(sc, "gre_sosend failed %d\n", rc);
223 	}
224 }
225 
226 /* Caller must hold sc->sc_mtx. */
227 static void
228 gre_fp_wait(struct gre_softc *sc)
229 {
230 	sc->sc_fp_waiters++;
231 	cv_wait(&sc->sc_fp_condvar, &sc->sc_mtx);
232 	sc->sc_fp_waiters--;
233 }
234 
235 static void
236 gre_evcnt_detach(struct gre_softc *sc)
237 {
238 	evcnt_detach(&sc->sc_recv_ev);
239 	evcnt_detach(&sc->sc_block_ev);
240 	evcnt_detach(&sc->sc_error_ev);
241 	evcnt_detach(&sc->sc_pullup_ev);
242 	evcnt_detach(&sc->sc_unsupp_ev);
243 
244 	evcnt_detach(&sc->sc_send_ev);
245 	evcnt_detach(&sc->sc_oflow_ev);
246 }
247 
248 static void
249 gre_evcnt_attach(struct gre_softc *sc)
250 {
251 	evcnt_attach_dynamic(&sc->sc_recv_ev, EVCNT_TYPE_MISC,
252 	    NULL, sc->sc_if.if_xname, "recv");
253 	evcnt_attach_dynamic(&sc->sc_block_ev, EVCNT_TYPE_MISC,
254 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "would block");
255 	evcnt_attach_dynamic(&sc->sc_error_ev, EVCNT_TYPE_MISC,
256 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "error");
257 	evcnt_attach_dynamic(&sc->sc_pullup_ev, EVCNT_TYPE_MISC,
258 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "pullup failed");
259 	evcnt_attach_dynamic(&sc->sc_unsupp_ev, EVCNT_TYPE_MISC,
260 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "unsupported");
261 
262 	evcnt_attach_dynamic(&sc->sc_send_ev, EVCNT_TYPE_MISC,
263 	    NULL, sc->sc_if.if_xname, "send");
264 	evcnt_attach_dynamic(&sc->sc_oflow_ev, EVCNT_TYPE_MISC,
265 	    &sc->sc_send_ev, sc->sc_if.if_xname, "overflow");
266 }
267 
268 static int
269 gre_clone_create(struct if_clone *ifc, int unit)
270 {
271 	int rc;
272 	struct gre_softc *sc;
273 	struct gre_soparm *sp;
274 	const struct sockaddr *any;
275 
276 	if ((any = sockaddr_any_by_family(AF_INET)) == NULL &&
277 	    (any = sockaddr_any_by_family(AF_INET6)) == NULL)
278 		return -1;
279 
280 	sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK|M_ZERO);
281 	mutex_init(&sc->sc_mtx, MUTEX_DRIVER, IPL_SOFTNET);
282 	cv_init(&sc->sc_condvar, "gre wait");
283 	cv_init(&sc->sc_fp_condvar, "gre fp");
284 
285 	if_initname(&sc->sc_if, ifc->ifc_name, unit);
286 	sc->sc_if.if_softc = sc;
287 	sc->sc_if.if_type = IFT_TUNNEL;
288 	sc->sc_if.if_addrlen = 0;
289 	sc->sc_if.if_hdrlen = sizeof(struct ip) + sizeof(struct gre_h);
290 	sc->sc_if.if_dlt = DLT_NULL;
291 	sc->sc_if.if_mtu = GREMTU;
292 	sc->sc_if.if_flags = IFF_POINTOPOINT|IFF_MULTICAST;
293 	sc->sc_if.if_output = gre_output;
294 	sc->sc_if.if_ioctl = gre_ioctl;
295 	sp = &sc->sc_soparm;
296 	sockaddr_copy(sstosa(&sp->sp_dst), sizeof(sp->sp_dst), any);
297 	sockaddr_copy(sstosa(&sp->sp_src), sizeof(sp->sp_src), any);
298 	sp->sp_proto = IPPROTO_GRE;
299 	sp->sp_type = SOCK_RAW;
300 
301 	sc->sc_fd = -1;
302 
303 	rc = kthread_create(PRI_NONE, KTHREAD_MPSAFE, NULL, gre_fp_recvloop, sc,
304 	    NULL, "%s", sc->sc_if.if_xname);
305 
306 	if (rc != 0)
307 		return -1;
308 
309 	gre_evcnt_attach(sc);
310 
311 	gre_bufq_init(&sc->sc_snd, 17);
312 	sc->sc_if.if_flags |= IFF_LINK0;
313 	if_attach(&sc->sc_if);
314 	if_alloc_sadl(&sc->sc_if);
315 	bpf_attach(&sc->sc_if, DLT_NULL, sizeof(uint32_t));
316 	return 0;
317 }
318 
319 static int
320 gre_clone_destroy(struct ifnet *ifp)
321 {
322 	int s;
323 	struct gre_softc *sc = ifp->if_softc;
324 
325 	GRE_DPRINTF(sc, "\n");
326 
327 	bpf_detach(ifp);
328 	s = splnet();
329 	if_detach(ifp);
330 
331 	GRE_DPRINTF(sc, "\n");
332 	/* Note that we must not hold the mutex while we call gre_reconf(). */
333 	gre_reconf(sc, NULL);
334 
335 	mutex_enter(&sc->sc_mtx);
336 	sc->sc_msg = GRE_M_STOP;
337 	cv_signal(&sc->sc_fp_condvar);
338 	while (sc->sc_fp_waiters > 0)
339 		cv_wait(&sc->sc_fp_condvar, &sc->sc_mtx);
340 	mutex_exit(&sc->sc_mtx);
341 
342 	splx(s);
343 
344 	cv_destroy(&sc->sc_condvar);
345 	cv_destroy(&sc->sc_fp_condvar);
346 	mutex_destroy(&sc->sc_mtx);
347 	gre_bufq_destroy(&sc->sc_snd);
348 	gre_evcnt_detach(sc);
349 	free(sc, M_DEVBUF);
350 
351 	return 0;
352 }
353 
354 static void
355 gre_receive(struct socket *so, void *arg, int events, int waitflag)
356 {
357 	struct gre_softc *sc = (struct gre_softc *)arg;
358 	int rc;
359 	const struct gre_h *gh;
360 	struct mbuf *m;
361 
362 	GRE_DPRINTF(sc, "enter\n");
363 
364 	sc->sc_recv_ev.ev_count++;
365 
366 	rc = gre_soreceive(so, &m);
367 	/* TBD Back off if ECONNREFUSED (indicates
368 	 * ICMP Port Unreachable)?
369 	 */
370 	if (rc == EWOULDBLOCK) {
371 		GRE_DPRINTF(sc, "EWOULDBLOCK\n");
372 		sc->sc_block_ev.ev_count++;
373 		return;
374 	} else if (rc != 0 || m == NULL) {
375 		GRE_DPRINTF(sc, "%s: rc %d m %p\n",
376 		    sc->sc_if.if_xname, rc, (void *)m);
377 		sc->sc_error_ev.ev_count++;
378 		return;
379 	}
380 	if (m->m_len < sizeof(*gh) && (m = m_pullup(m, sizeof(*gh))) == NULL) {
381 		GRE_DPRINTF(sc, "m_pullup failed\n");
382 		sc->sc_pullup_ev.ev_count++;
383 		return;
384 	}
385 	gh = mtod(m, const struct gre_h *);
386 
387 	if (gre_input(sc, m, 0, gh) == 0) {
388 		sc->sc_unsupp_ev.ev_count++;
389 		GRE_DPRINTF(sc, "dropping unsupported\n");
390 		m_freem(m);
391 	}
392 }
393 
394 static void
395 gre_upcall_add(struct socket *so, void *arg)
396 {
397 	/* XXX What if the kernel already set an upcall? */
398 	KASSERT((so->so_rcv.sb_flags & SB_UPCALL) == 0);
399 	so->so_upcallarg = arg;
400 	so->so_upcall = gre_receive;
401 	so->so_rcv.sb_flags |= SB_UPCALL;
402 }
403 
404 static void
405 gre_upcall_remove(struct socket *so)
406 {
407 	so->so_rcv.sb_flags &= ~SB_UPCALL;
408 	so->so_upcallarg = NULL;
409 	so->so_upcall = NULL;
410 }
411 
412 static int
413 gre_socreate(struct gre_softc *sc, const struct gre_soparm *sp, int *fdout)
414 {
415 	const struct protosw *pr;
416 	int fd, rc;
417 	struct mbuf *m;
418 	struct sockaddr *sa;
419 	struct socket *so;
420 	sa_family_t af;
421 	int val;
422 
423 	GRE_DPRINTF(sc, "enter\n");
424 
425 	af = sp->sp_src.ss_family;
426 	rc = fsocreate(af, NULL, sp->sp_type, sp->sp_proto, curlwp, &fd);
427 	if (rc != 0) {
428 		GRE_DPRINTF(sc, "fsocreate failed\n");
429 		return rc;
430 	}
431 
432 	if ((rc = fd_getsock(fd, &so)) != 0)
433 		return rc;
434 
435 	if ((m = getsombuf(so, MT_SONAME)) == NULL) {
436 		rc = ENOBUFS;
437 		goto out;
438 	}
439 	sa = mtod(m, struct sockaddr *);
440 	sockaddr_copy(sa, MIN(MLEN, sizeof(sp->sp_src)), sstocsa(&sp->sp_src));
441 	m->m_len = sp->sp_src.ss_len;
442 
443 	if ((rc = sobind(so, m, curlwp)) != 0) {
444 		GRE_DPRINTF(sc, "sobind failed\n");
445 		goto out;
446 	}
447 
448 	sockaddr_copy(sa, MIN(MLEN, sizeof(sp->sp_dst)), sstocsa(&sp->sp_dst));
449 	m->m_len = sp->sp_dst.ss_len;
450 
451 	solock(so);
452 	if ((rc = soconnect(so, m, curlwp)) != 0) {
453 		GRE_DPRINTF(sc, "soconnect failed\n");
454 		sounlock(so);
455 		goto out;
456 	}
457 	sounlock(so);
458 
459 	m = NULL;
460 
461 	/* XXX convert to a (new) SOL_SOCKET call */
462   	pr = so->so_proto;
463   	KASSERT(pr != NULL);
464  	rc = so_setsockopt(curlwp, so, IPPROTO_IP, IP_TTL,
465 	    &ip_gre_ttl, sizeof(ip_gre_ttl));
466   	if (rc != 0) {
467  		GRE_DPRINTF(sc, "so_setsockopt ttl failed\n");
468   		rc = 0;
469   	}
470 
471  	val = 1;
472  	rc = so_setsockopt(curlwp, so, SOL_SOCKET, SO_NOHEADER,
473 	    &val, sizeof(val));
474   	if (rc != 0) {
475  		GRE_DPRINTF(sc, "so_setsockopt SO_NOHEADER failed\n");
476 		rc = 0;
477 	}
478 out:
479 	m_freem(m);
480 
481 	if (rc != 0)
482 		fd_close(fd);
483 	else  {
484 		fd_putfile(fd);
485 		*fdout = fd;
486 	}
487 
488 	return rc;
489 }
490 
491 static int
492 gre_sosend(struct socket *so, struct mbuf *top)
493 {
494 	struct mbuf	**mp;
495 	struct proc	*p;
496 	long		space, resid;
497 	int		error;
498 	struct lwp * const l = curlwp;
499 
500 	p = l->l_proc;
501 
502 	resid = top->m_pkthdr.len;
503 	if (p)
504 		l->l_ru.ru_msgsnd++;
505 #define	snderr(errno)	{ error = errno; goto release; }
506 
507 	solock(so);
508 	if ((error = sblock(&so->so_snd, M_NOWAIT)) != 0)
509 		goto out;
510 	if (so->so_state & SS_CANTSENDMORE)
511 		snderr(EPIPE);
512 	if (so->so_error) {
513 		error = so->so_error;
514 		so->so_error = 0;
515 		goto release;
516 	}
517 	if ((so->so_state & SS_ISCONNECTED) == 0) {
518 		if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
519 			snderr(ENOTCONN);
520 		} else {
521 			snderr(EDESTADDRREQ);
522 		}
523 	}
524 	space = sbspace(&so->so_snd);
525 	if (resid > so->so_snd.sb_hiwat)
526 		snderr(EMSGSIZE);
527 	if (space < resid)
528 		snderr(EWOULDBLOCK);
529 	mp = &top;
530 	/*
531 	 * Data is prepackaged in "top".
532 	 */
533 	if (so->so_state & SS_CANTSENDMORE)
534 		snderr(EPIPE);
535 	error = (*so->so_proto->pr_usrreq)(so, PRU_SEND, top, NULL, NULL, l);
536 	top = NULL;
537 	mp = &top;
538  release:
539 	sbunlock(&so->so_snd);
540  out:
541  	sounlock(so);
542 	if (top != NULL)
543 		m_freem(top);
544 	return error;
545 }
546 
547 /* This is a stripped-down version of soreceive() that will never
548  * block.  It will support SOCK_DGRAM sockets.  It may also support
549  * SOCK_SEQPACKET sockets.
550  */
551 static int
552 gre_soreceive(struct socket *so, struct mbuf **mp0)
553 {
554 	struct mbuf *m, **mp;
555 	int flags, len, error, type;
556 	const struct protosw	*pr;
557 	struct mbuf *nextrecord;
558 
559 	KASSERT(mp0 != NULL);
560 
561 	flags = MSG_DONTWAIT;
562 	pr = so->so_proto;
563 	mp = mp0;
564 	type = 0;
565 
566 	*mp = NULL;
567 
568 	KASSERT(pr->pr_flags & PR_ATOMIC);
569  restart:
570 	if ((error = sblock(&so->so_rcv, M_NOWAIT)) != 0) {
571 		return error;
572 	}
573 	m = so->so_rcv.sb_mb;
574 	/*
575 	 * If we have less data than requested, do not block awaiting more.
576 	 */
577 	if (m == NULL) {
578 #ifdef DIAGNOSTIC
579 		if (so->so_rcv.sb_cc)
580 			panic("receive 1");
581 #endif
582 		if (so->so_error) {
583 			error = so->so_error;
584 			so->so_error = 0;
585 		} else if (so->so_state & SS_CANTRCVMORE)
586 			;
587 		else if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0
588 		      && (so->so_proto->pr_flags & PR_CONNREQUIRED))
589 			error = ENOTCONN;
590 		else
591 			error = EWOULDBLOCK;
592 		goto release;
593 	}
594 	/*
595 	 * On entry here, m points to the first record of the socket buffer.
596 	 * While we process the initial mbufs containing address and control
597 	 * info, we save a copy of m->m_nextpkt into nextrecord.
598 	 */
599 	if (curlwp != NULL)
600 		curlwp->l_ru.ru_msgrcv++;
601 	KASSERT(m == so->so_rcv.sb_mb);
602 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 1");
603 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 1");
604 	nextrecord = m->m_nextpkt;
605 	if (pr->pr_flags & PR_ADDR) {
606 #ifdef DIAGNOSTIC
607 		if (m->m_type != MT_SONAME)
608 			panic("receive 1a");
609 #endif
610 		sbfree(&so->so_rcv, m);
611 		MFREE(m, so->so_rcv.sb_mb);
612 		m = so->so_rcv.sb_mb;
613 	}
614 	while (m != NULL && m->m_type == MT_CONTROL && error == 0) {
615 		sbfree(&so->so_rcv, m);
616 		/*
617 		 * Dispose of any SCM_RIGHTS message that went
618 		 * through the read path rather than recv.
619 		 */
620 		if (pr->pr_domain->dom_dispose &&
621 		    mtod(m, struct cmsghdr *)->cmsg_type == SCM_RIGHTS)
622 			(*pr->pr_domain->dom_dispose)(m);
623 		MFREE(m, so->so_rcv.sb_mb);
624 		m = so->so_rcv.sb_mb;
625 	}
626 
627 	/*
628 	 * If m is non-NULL, we have some data to read.  From now on,
629 	 * make sure to keep sb_lastrecord consistent when working on
630 	 * the last packet on the chain (nextrecord == NULL) and we
631 	 * change m->m_nextpkt.
632 	 */
633 	if (m != NULL) {
634 		m->m_nextpkt = nextrecord;
635 		/*
636 		 * If nextrecord == NULL (this is a single chain),
637 		 * then sb_lastrecord may not be valid here if m
638 		 * was changed earlier.
639 		 */
640 		if (nextrecord == NULL) {
641 			KASSERT(so->so_rcv.sb_mb == m);
642 			so->so_rcv.sb_lastrecord = m;
643 		}
644 		type = m->m_type;
645 		if (type == MT_OOBDATA)
646 			flags |= MSG_OOB;
647 	} else {
648 		KASSERT(so->so_rcv.sb_mb == m);
649 		so->so_rcv.sb_mb = nextrecord;
650 		SB_EMPTY_FIXUP(&so->so_rcv);
651 	}
652 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 2");
653 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 2");
654 
655 	while (m != NULL) {
656 		if (m->m_type == MT_OOBDATA) {
657 			if (type != MT_OOBDATA)
658 				break;
659 		} else if (type == MT_OOBDATA)
660 			break;
661 #ifdef DIAGNOSTIC
662 		else if (m->m_type != MT_DATA && m->m_type != MT_HEADER)
663 			panic("receive 3");
664 #endif
665 		so->so_state &= ~SS_RCVATMARK;
666 		if (so->so_oobmark != 0 && so->so_oobmark < m->m_len)
667 			break;
668 		len = m->m_len;
669 		/*
670 		 * mp is set, just pass back the mbufs.
671 		 * Sockbuf must be consistent here (points to current mbuf,
672 		 * it points to next record) when we drop priority;
673 		 * we must note any additions to the sockbuf when we
674 		 * block interrupts again.
675 		 */
676 		if (m->m_flags & M_EOR)
677 			flags |= MSG_EOR;
678 		nextrecord = m->m_nextpkt;
679 		sbfree(&so->so_rcv, m);
680 		*mp = m;
681 		mp = &m->m_next;
682 		so->so_rcv.sb_mb = m = m->m_next;
683 		*mp = NULL;
684 		/*
685 		 * If m != NULL, we also know that
686 		 * so->so_rcv.sb_mb != NULL.
687 		 */
688 		KASSERT(so->so_rcv.sb_mb == m);
689 		if (m) {
690 			m->m_nextpkt = nextrecord;
691 			if (nextrecord == NULL)
692 				so->so_rcv.sb_lastrecord = m;
693 		} else {
694 			so->so_rcv.sb_mb = nextrecord;
695 			SB_EMPTY_FIXUP(&so->so_rcv);
696 		}
697 		SBLASTRECORDCHK(&so->so_rcv, "soreceive 3");
698 		SBLASTMBUFCHK(&so->so_rcv, "soreceive 3");
699 		if (so->so_oobmark) {
700 			so->so_oobmark -= len;
701 			if (so->so_oobmark == 0) {
702 				so->so_state |= SS_RCVATMARK;
703 				break;
704 			}
705 		}
706 		if (flags & MSG_EOR)
707 			break;
708 	}
709 
710 	if (m != NULL) {
711 		m_freem(*mp);
712 		*mp = NULL;
713 		error = ENOMEM;
714 		(void) sbdroprecord(&so->so_rcv);
715 	} else {
716 		/*
717 		 * First part is an inline SB_EMPTY_FIXUP().  Second
718 		 * part makes sure sb_lastrecord is up-to-date if
719 		 * there is still data in the socket buffer.
720 		 */
721 		so->so_rcv.sb_mb = nextrecord;
722 		if (so->so_rcv.sb_mb == NULL) {
723 			so->so_rcv.sb_mbtail = NULL;
724 			so->so_rcv.sb_lastrecord = NULL;
725 		} else if (nextrecord->m_nextpkt == NULL)
726 			so->so_rcv.sb_lastrecord = nextrecord;
727 	}
728 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 4");
729 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 4");
730 	if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
731 		(*pr->pr_usrreq)(so, PRU_RCVD, NULL,
732 		    (struct mbuf *)(long)flags, NULL, curlwp);
733 	if (*mp0 == NULL && (flags & MSG_EOR) == 0 &&
734 	    (so->so_state & SS_CANTRCVMORE) == 0) {
735 		sbunlock(&so->so_rcv);
736 		goto restart;
737 	}
738 
739  release:
740 	sbunlock(&so->so_rcv);
741 	return error;
742 }
743 
744 static struct socket *
745 gre_reconf(struct gre_softc *sc, const struct gre_soparm *newsoparm)
746 {
747 	struct ifnet *ifp = &sc->sc_if;
748 
749 	GRE_DPRINTF(sc, "enter\n");
750 
751 shutdown:
752 	if (sc->sc_soparm.sp_so != NULL) {
753 		GRE_DPRINTF(sc, "\n");
754 		gre_upcall_remove(sc->sc_soparm.sp_so);
755 		softint_disestablish(sc->sc_si);
756 		sc->sc_si = NULL;
757 		gre_fp_send(sc, GRE_M_DELFP, NULL);
758 		gre_clearconf(&sc->sc_soparm, false);
759 	}
760 
761 	if (newsoparm != NULL) {
762 		GRE_DPRINTF(sc, "\n");
763 		sc->sc_soparm = *newsoparm;
764 		newsoparm = NULL;
765 	}
766 
767 	if (sc->sc_soparm.sp_so != NULL) {
768 		GRE_DPRINTF(sc, "\n");
769 		sc->sc_si = softint_establish(SOFTINT_NET, greintr, sc);
770 		gre_upcall_add(sc->sc_soparm.sp_so, sc);
771 		if ((ifp->if_flags & IFF_UP) == 0) {
772 			GRE_DPRINTF(sc, "down\n");
773 			goto shutdown;
774 		}
775 	}
776 
777 	GRE_DPRINTF(sc, "\n");
778 	if (sc->sc_soparm.sp_so != NULL)
779 		sc->sc_if.if_flags |= IFF_RUNNING;
780 	else {
781 		gre_bufq_purge(&sc->sc_snd);
782 		sc->sc_if.if_flags &= ~IFF_RUNNING;
783 	}
784 	return sc->sc_soparm.sp_so;
785 }
786 
787 static int
788 gre_input(struct gre_softc *sc, struct mbuf *m, int hlen,
789     const struct gre_h *gh)
790 {
791 	uint16_t flags;
792 	uint32_t af;		/* af passed to BPF tap */
793 	int isr, s;
794 	struct ifqueue *ifq;
795 
796 	sc->sc_if.if_ipackets++;
797 	sc->sc_if.if_ibytes += m->m_pkthdr.len;
798 
799 	hlen += sizeof(struct gre_h);
800 
801 	/* process GRE flags as packet can be of variable len */
802 	flags = ntohs(gh->flags);
803 
804 	/* Checksum & Offset are present */
805 	if ((flags & GRE_CP) | (flags & GRE_RP))
806 		hlen += 4;
807 	/* We don't support routing fields (variable length) */
808 	if (flags & GRE_RP) {
809 		sc->sc_if.if_ierrors++;
810 		return 0;
811 	}
812 	if (flags & GRE_KP)
813 		hlen += 4;
814 	if (flags & GRE_SP)
815 		hlen += 4;
816 
817 	switch (ntohs(gh->ptype)) { /* ethertypes */
818 #ifdef INET
819 	case ETHERTYPE_IP:
820 		ifq = &ipintrq;
821 		isr = NETISR_IP;
822 		af = AF_INET;
823 		break;
824 #endif
825 #ifdef NETATALK
826 	case ETHERTYPE_ATALK:
827 		ifq = &atintrq1;
828 		isr = NETISR_ATALK;
829 		af = AF_APPLETALK;
830 		break;
831 #endif
832 #ifdef INET6
833 	case ETHERTYPE_IPV6:
834 		ifq = &ip6intrq;
835 		isr = NETISR_IPV6;
836 		af = AF_INET6;
837 		break;
838 #endif
839 #ifdef MPLS
840 	case ETHERTYPE_MPLS:
841 		ifq = &mplsintrq;
842 		isr = NETISR_MPLS;
843 		af = AF_MPLS;
844 		break;
845 #endif
846 	default:	   /* others not yet supported */
847 		GRE_DPRINTF(sc, "unhandled ethertype 0x%04x\n",
848 		    ntohs(gh->ptype));
849 		sc->sc_if.if_noproto++;
850 		return 0;
851 	}
852 
853 	if (hlen > m->m_pkthdr.len) {
854 		m_freem(m);
855 		sc->sc_if.if_ierrors++;
856 		return EINVAL;
857 	}
858 	m_adj(m, hlen);
859 
860 	bpf_mtap_af(&sc->sc_if, af, m);
861 
862 	m->m_pkthdr.rcvif = &sc->sc_if;
863 
864 	s = splnet();
865 	if (IF_QFULL(ifq)) {
866 		IF_DROP(ifq);
867 		m_freem(m);
868 	} else {
869 		IF_ENQUEUE(ifq, m);
870 	}
871 	/* we need schednetisr since the address family may change */
872 	schednetisr(isr);
873 	splx(s);
874 
875 	return 1;	/* packet is done, no further processing needed */
876 }
877 
878 /*
879  * The output routine. Takes a packet and encapsulates it in the protocol
880  * given by sc->sc_soparm.sp_proto. See also RFC 1701 and RFC 2004
881  */
882 static int
883 gre_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
884 	   struct rtentry *rt)
885 {
886 	int error = 0;
887 	struct gre_softc *sc = ifp->if_softc;
888 	struct gre_h *gh;
889 	uint16_t etype = 0;
890 
891 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) {
892 		m_freem(m);
893 		error = ENETDOWN;
894 		goto end;
895 	}
896 
897 	bpf_mtap_af(ifp, dst->sa_family, m);
898 
899 	m->m_flags &= ~(M_BCAST|M_MCAST);
900 
901 	GRE_DPRINTF(sc, "dst->sa_family=%d\n", dst->sa_family);
902 	switch (dst->sa_family) {
903 #ifdef INET
904 	case AF_INET:
905 		/* TBD Extract the IP ToS field and set the
906 		 * encapsulating protocol's ToS to suit.
907 		 */
908 		etype = htons(ETHERTYPE_IP);
909 		break;
910 #endif
911 #ifdef NETATALK
912 	case AF_APPLETALK:
913 		etype = htons(ETHERTYPE_ATALK);
914 		break;
915 #endif
916 #ifdef INET6
917 	case AF_INET6:
918 		etype = htons(ETHERTYPE_IPV6);
919 		break;
920 #endif
921 	default:
922 		IF_DROP(&ifp->if_snd);
923 		m_freem(m);
924 		error = EAFNOSUPPORT;
925 		goto end;
926 	}
927 
928 #ifdef MPLS
929 		if (rt != NULL && rt_gettag(rt) != NULL) {
930 			union mpls_shim msh;
931 			msh.s_addr = MPLS_GETSADDR(rt);
932 			if (msh.shim.label != MPLS_LABEL_IMPLNULL)
933 				etype = htons(ETHERTYPE_MPLS);
934 		}
935 #endif
936 
937 	M_PREPEND(m, sizeof(*gh), M_DONTWAIT);
938 
939 	if (m == NULL) {
940 		IF_DROP(&ifp->if_snd);
941 		error = ENOBUFS;
942 		goto end;
943 	}
944 
945 	gh = mtod(m, struct gre_h *);
946 	gh->flags = 0;
947 	gh->ptype = etype;
948 	/* XXX Need to handle IP ToS.  Look at how I handle IP TTL. */
949 
950 	ifp->if_opackets++;
951 	ifp->if_obytes += m->m_pkthdr.len;
952 
953 	/* Clear checksum-offload flags. */
954 	m->m_pkthdr.csum_flags = 0;
955 	m->m_pkthdr.csum_data = 0;
956 
957 	/* send it off */
958 	if ((error = gre_bufq_enqueue(&sc->sc_snd, m)) != 0) {
959 		sc->sc_oflow_ev.ev_count++;
960 		m_freem(m);
961 	} else
962 		softint_schedule(sc->sc_si);
963   end:
964 	if (error)
965 		ifp->if_oerrors++;
966 	return error;
967 }
968 
969 static int
970 gre_getname(struct socket *so, int req, struct mbuf *nam, struct lwp *l)
971 {
972 	return (*so->so_proto->pr_usrreq)(so, req, NULL, nam, NULL, l);
973 }
974 
975 static int
976 gre_getsockname(struct socket *so, struct mbuf *nam, struct lwp *l)
977 {
978 	return gre_getname(so, PRU_SOCKADDR, nam, l);
979 }
980 
981 static int
982 gre_getpeername(struct socket *so, struct mbuf *nam, struct lwp *l)
983 {
984 	return gre_getname(so, PRU_PEERADDR, nam, l);
985 }
986 
987 static int
988 gre_getnames(struct socket *so, struct lwp *l, struct sockaddr_storage *src,
989     struct sockaddr_storage *dst)
990 {
991 	struct mbuf *m;
992 	struct sockaddr_storage *ss;
993 	int rc;
994 
995 	if ((m = getsombuf(so, MT_SONAME)) == NULL)
996 		return ENOBUFS;
997 
998 	ss = mtod(m, struct sockaddr_storage *);
999 
1000 	solock(so);
1001 	if ((rc = gre_getsockname(so, m, l)) != 0)
1002 		goto out;
1003 	*src = *ss;
1004 
1005 	if ((rc = gre_getpeername(so, m, l)) != 0)
1006 		goto out;
1007 	*dst = *ss;
1008 out:
1009 	sounlock(so);
1010 	m_freem(m);
1011 	return rc;
1012 }
1013 
1014 static void
1015 gre_fp_recvloop(void *arg)
1016 {
1017 	struct gre_softc *sc = arg;
1018 
1019 	mutex_enter(&sc->sc_mtx);
1020 	while (gre_fp_recv(sc))
1021 		;
1022 	mutex_exit(&sc->sc_mtx);
1023 	kthread_exit(0);
1024 }
1025 
1026 static bool
1027 gre_fp_recv(struct gre_softc *sc)
1028 {
1029 	int fd, ofd, rc;
1030 	file_t *fp;
1031 
1032 	fp = sc->sc_fp;
1033 	ofd = sc->sc_fd;
1034 	fd = -1;
1035 
1036 	switch (sc->sc_msg) {
1037 	case GRE_M_STOP:
1038 		cv_signal(&sc->sc_fp_condvar);
1039 		return false;
1040 	case GRE_M_SETFP:
1041 		mutex_exit(&sc->sc_mtx);
1042 		rc = fd_dup(fp, 0, &fd, 0);
1043 		mutex_enter(&sc->sc_mtx);
1044 		if (rc != 0) {
1045 			sc->sc_msg = GRE_M_ERR;
1046 			break;
1047 		}
1048 		/*FALLTHROUGH*/
1049 	case GRE_M_DELFP:
1050 		mutex_exit(&sc->sc_mtx);
1051 		if (ofd != -1 && fd_getfile(ofd) != NULL)
1052 			fd_close(ofd);
1053 		mutex_enter(&sc->sc_mtx);
1054 		sc->sc_fd = fd;
1055 		sc->sc_msg = GRE_M_OK;
1056 		break;
1057 	default:
1058 		gre_fp_wait(sc);
1059 		return true;
1060 	}
1061 	cv_signal(&sc->sc_fp_condvar);
1062 	return true;
1063 }
1064 
1065 static bool
1066 gre_fp_send(struct gre_softc *sc, enum gre_msg msg, file_t *fp)
1067 {
1068 	bool rc;
1069 
1070 	mutex_enter(&sc->sc_mtx);
1071 	while (sc->sc_msg != GRE_M_NONE)
1072 		gre_fp_wait(sc);
1073 	sc->sc_fp = fp;
1074 	sc->sc_msg = msg;
1075 	cv_signal(&sc->sc_fp_condvar);
1076 	while (sc->sc_msg != GRE_M_STOP && sc->sc_msg != GRE_M_OK &&
1077 	            sc->sc_msg != GRE_M_ERR)
1078 		gre_fp_wait(sc);
1079 	rc = (sc->sc_msg != GRE_M_ERR);
1080 	sc->sc_msg = GRE_M_NONE;
1081 	cv_signal(&sc->sc_fp_condvar);
1082 	mutex_exit(&sc->sc_mtx);
1083 	return rc;
1084 }
1085 
1086 static int
1087 gre_ssock(struct ifnet *ifp, struct gre_soparm *sp, int fd)
1088 {
1089 	int error = 0;
1090 	const struct protosw *pr;
1091 	file_t *fp;
1092 	struct gre_softc *sc = ifp->if_softc;
1093 	struct socket *so;
1094 	struct sockaddr_storage dst, src;
1095 
1096 	if ((fp = fd_getfile(fd)) == NULL)
1097 		return EBADF;
1098 	if (fp->f_type != DTYPE_SOCKET) {
1099 		fd_putfile(fd);
1100 		return ENOTSOCK;
1101 	}
1102 
1103 	GRE_DPRINTF(sc, "\n");
1104 
1105 	so = (struct socket *)fp->f_data;
1106 	pr = so->so_proto;
1107 
1108 	GRE_DPRINTF(sc, "type %d, proto %d\n", pr->pr_type, pr->pr_protocol);
1109 
1110 	if ((pr->pr_flags & PR_ATOMIC) == 0 ||
1111 	    (sp->sp_type != 0 && pr->pr_type != sp->sp_type) ||
1112 	    (sp->sp_proto != 0 && pr->pr_protocol != 0 &&
1113 	     pr->pr_protocol != sp->sp_proto)) {
1114 		error = EINVAL;
1115 		goto err;
1116 	}
1117 
1118 	GRE_DPRINTF(sc, "\n");
1119 
1120 	/* check address */
1121 	if ((error = gre_getnames(so, curlwp, &src, &dst)) != 0)
1122 		goto err;
1123 
1124 	GRE_DPRINTF(sc, "\n");
1125 
1126 	if (!gre_fp_send(sc, GRE_M_SETFP, fp)) {
1127 		error = EBUSY;
1128 		goto err;
1129 	}
1130 
1131 	GRE_DPRINTF(sc, "\n");
1132 
1133 	sp->sp_src = src;
1134 	sp->sp_dst = dst;
1135 
1136 	sp->sp_so = so;
1137 
1138 err:
1139 	fd_putfile(fd);
1140 	return error;
1141 }
1142 
1143 static bool
1144 sockaddr_is_anyaddr(const struct sockaddr *sa)
1145 {
1146 	socklen_t anylen, salen;
1147 	const void *anyaddr, *addr;
1148 
1149 	if ((anyaddr = sockaddr_anyaddr(sa, &anylen)) == NULL ||
1150 	    (addr = sockaddr_const_addr(sa, &salen)) == NULL)
1151 		return false;
1152 
1153 	if (salen > anylen)
1154 		return false;
1155 
1156 	return memcmp(anyaddr, addr, MIN(anylen, salen)) == 0;
1157 }
1158 
1159 static bool
1160 gre_is_nullconf(const struct gre_soparm *sp)
1161 {
1162 	return sockaddr_is_anyaddr(sstocsa(&sp->sp_src)) ||
1163 	       sockaddr_is_anyaddr(sstocsa(&sp->sp_dst));
1164 }
1165 
1166 static void
1167 gre_clearconf(struct gre_soparm *sp, bool force)
1168 {
1169 	if (sp->sp_bysock || force) {
1170 		sockaddr_copy(sstosa(&sp->sp_src), sizeof(sp->sp_src),
1171 		    sockaddr_any(sstosa(&sp->sp_src)));
1172 		sockaddr_copy(sstosa(&sp->sp_dst), sizeof(sp->sp_dst),
1173 		    sockaddr_any(sstosa(&sp->sp_dst)));
1174 		sp->sp_bysock = false;
1175 	}
1176 	sp->sp_so = NULL; /* XXX */
1177 }
1178 
1179 static int
1180 gre_ioctl(struct ifnet *ifp, const u_long cmd, void *data)
1181 {
1182 	struct ifreq *ifr;
1183 	struct if_laddrreq *lifr = (struct if_laddrreq *)data;
1184 	struct gre_softc *sc = ifp->if_softc;
1185 	struct gre_soparm *sp;
1186 	int fd, error = 0, oproto, otype, s;
1187 	struct gre_soparm sp0;
1188 
1189 	ifr = data;
1190 
1191 	GRE_DPRINTF(sc, "cmd %lu\n", cmd);
1192 
1193 	switch (cmd) {
1194 	case GRESPROTO:
1195 	case GRESADDRD:
1196 	case GRESADDRS:
1197 	case GRESSOCK:
1198 	case GREDSOCK:
1199 		if (kauth_authorize_network(curlwp->l_cred,
1200 		    KAUTH_NETWORK_INTERFACE,
1201 		    KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
1202 		    NULL) != 0)
1203 			return EPERM;
1204 		break;
1205 	default:
1206 		break;
1207 	}
1208 
1209 	s = splnet();
1210 
1211 	sp0 = sc->sc_soparm;
1212 	sp0.sp_so = NULL;
1213 	sp = &sp0;
1214 
1215 	GRE_DPRINTF(sc, "\n");
1216 
1217 	switch (cmd) {
1218 	case SIOCINITIFADDR:
1219 		GRE_DPRINTF(sc, "\n");
1220 		if ((ifp->if_flags & IFF_UP) != 0)
1221 			break;
1222 		gre_clearconf(sp, false);
1223 		ifp->if_flags |= IFF_UP;
1224 		goto mksocket;
1225 	case SIOCSIFFLAGS:
1226 		if ((error = ifioctl_common(ifp, cmd, data)) != 0)
1227 			break;
1228 		oproto = sp->sp_proto;
1229 		otype = sp->sp_type;
1230 		switch (ifr->ifr_flags & (IFF_LINK0|IFF_LINK2)) {
1231 		case IFF_LINK0|IFF_LINK2:
1232 			sp->sp_proto = IPPROTO_UDP;
1233 			sp->sp_type = SOCK_DGRAM;
1234 			break;
1235 		case IFF_LINK2:
1236 			sp->sp_proto = 0;
1237 			sp->sp_type = 0;
1238 			break;
1239 		case IFF_LINK0:
1240 			sp->sp_proto = IPPROTO_GRE;
1241 			sp->sp_type = SOCK_RAW;
1242 			break;
1243 		default:
1244 			GRE_DPRINTF(sc, "\n");
1245 			error = EINVAL;
1246 			goto out;
1247 		}
1248 		GRE_DPRINTF(sc, "\n");
1249 		gre_clearconf(sp, false);
1250 		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) ==
1251 		    (IFF_UP|IFF_RUNNING) &&
1252 		    (oproto == sp->sp_proto || sp->sp_proto == 0) &&
1253 		    (otype == sp->sp_type || sp->sp_type == 0))
1254 			break;
1255 		switch (sp->sp_proto) {
1256 		case IPPROTO_UDP:
1257 		case IPPROTO_GRE:
1258 			goto mksocket;
1259 		default:
1260 			break;
1261 		}
1262 		break;
1263 	case SIOCSIFMTU:
1264 		/* XXX determine MTU automatically by probing w/
1265 		 * XXX do-not-fragment packets?
1266 		 */
1267 		if (ifr->ifr_mtu < 576) {
1268 			error = EINVAL;
1269 			break;
1270 		}
1271 		/*FALLTHROUGH*/
1272 	case SIOCGIFMTU:
1273 		if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET)
1274 			error = 0;
1275 		break;
1276 	case SIOCADDMULTI:
1277 	case SIOCDELMULTI:
1278 		if (ifr == NULL) {
1279 			error = EAFNOSUPPORT;
1280 			break;
1281 		}
1282 		switch (ifreq_getaddr(cmd, ifr)->sa_family) {
1283 #ifdef INET
1284 		case AF_INET:
1285 			break;
1286 #endif
1287 #ifdef INET6
1288 		case AF_INET6:
1289 			break;
1290 #endif
1291 		default:
1292 			error = EAFNOSUPPORT;
1293 			break;
1294 		}
1295 		break;
1296 	case GRESPROTO:
1297 		gre_clearconf(sp, false);
1298 		oproto = sp->sp_proto;
1299 		otype = sp->sp_type;
1300 		sp->sp_proto = ifr->ifr_flags;
1301 		switch (sp->sp_proto) {
1302 		case IPPROTO_UDP:
1303 			ifp->if_flags |= IFF_LINK0|IFF_LINK2;
1304 			sp->sp_type = SOCK_DGRAM;
1305 			break;
1306 		case IPPROTO_GRE:
1307 			ifp->if_flags |= IFF_LINK0;
1308 			ifp->if_flags &= ~IFF_LINK2;
1309 			sp->sp_type = SOCK_RAW;
1310 			break;
1311 		case 0:
1312 			ifp->if_flags &= ~IFF_LINK0;
1313 			ifp->if_flags |= IFF_LINK2;
1314 			sp->sp_type = 0;
1315 			break;
1316 		default:
1317 			error = EPROTONOSUPPORT;
1318 			break;
1319 		}
1320 		if ((oproto == sp->sp_proto || sp->sp_proto == 0) &&
1321 		    (otype == sp->sp_type || sp->sp_type == 0))
1322 			break;
1323 		switch (sp->sp_proto) {
1324 		case IPPROTO_UDP:
1325 		case IPPROTO_GRE:
1326 			goto mksocket;
1327 		default:
1328 			break;
1329 		}
1330 		break;
1331 	case GREGPROTO:
1332 		ifr->ifr_flags = sp->sp_proto;
1333 		break;
1334 	case GRESADDRS:
1335 	case GRESADDRD:
1336 		gre_clearconf(sp, false);
1337 		/* set tunnel endpoints and mark interface as up */
1338 		switch (cmd) {
1339 		case GRESADDRS:
1340 			sockaddr_copy(sstosa(&sp->sp_src),
1341 			    sizeof(sp->sp_src), ifreq_getaddr(cmd, ifr));
1342 			break;
1343 		case GRESADDRD:
1344 			sockaddr_copy(sstosa(&sp->sp_dst),
1345 			    sizeof(sp->sp_dst), ifreq_getaddr(cmd, ifr));
1346 			break;
1347 		}
1348 	checkaddr:
1349 		if (sockaddr_any(sstosa(&sp->sp_src)) == NULL ||
1350 		    sockaddr_any(sstosa(&sp->sp_dst)) == NULL) {
1351 			error = EINVAL;
1352 			break;
1353 		}
1354 		/* let gre_socreate() check the rest */
1355 	mksocket:
1356 		GRE_DPRINTF(sc, "\n");
1357 		/* If we're administratively down, or the configuration
1358 		 * is empty, there's no use creating a socket.
1359 		 */
1360 		if ((ifp->if_flags & IFF_UP) == 0 || gre_is_nullconf(sp))
1361 			goto sendconf;
1362 
1363 		GRE_DPRINTF(sc, "\n");
1364 		fd = 0;
1365 		error = gre_socreate(sc, sp, &fd);
1366 		if (error != 0)
1367 			break;
1368 
1369 	setsock:
1370 		GRE_DPRINTF(sc, "\n");
1371 
1372 		error = gre_ssock(ifp, sp, fd);
1373 
1374 		if (cmd != GRESSOCK) {
1375 			GRE_DPRINTF(sc, "\n");
1376 			/* XXX v. dodgy */
1377 			if (fd_getfile(fd) != NULL)
1378 				fd_close(fd);
1379 		}
1380 
1381 		if (error == 0) {
1382 	sendconf:
1383 			GRE_DPRINTF(sc, "\n");
1384 			ifp->if_flags &= ~IFF_RUNNING;
1385 			gre_reconf(sc, sp);
1386 		}
1387 
1388 		break;
1389 	case GREGADDRS:
1390 		ifreq_setaddr(cmd, ifr, sstosa(&sp->sp_src));
1391 		break;
1392 	case GREGADDRD:
1393 		ifreq_setaddr(cmd, ifr, sstosa(&sp->sp_dst));
1394 		break;
1395 	case GREDSOCK:
1396 		GRE_DPRINTF(sc, "\n");
1397 		if (sp->sp_bysock)
1398 			ifp->if_flags &= ~IFF_UP;
1399 		gre_clearconf(sp, false);
1400 		goto mksocket;
1401 	case GRESSOCK:
1402 		GRE_DPRINTF(sc, "\n");
1403 		gre_clearconf(sp, true);
1404 		fd = (int)ifr->ifr_value;
1405 		sp->sp_bysock = true;
1406 		ifp->if_flags |= IFF_UP;
1407 		goto setsock;
1408 	case SIOCSLIFPHYADDR:
1409 		GRE_DPRINTF(sc, "\n");
1410 		if (lifr->addr.ss_family != lifr->dstaddr.ss_family) {
1411 			error = EAFNOSUPPORT;
1412 			break;
1413 		}
1414 		sockaddr_copy(sstosa(&sp->sp_src), sizeof(sp->sp_src),
1415 		    sstosa(&lifr->addr));
1416 		sockaddr_copy(sstosa(&sp->sp_dst), sizeof(sp->sp_dst),
1417 		    sstosa(&lifr->dstaddr));
1418 		GRE_DPRINTF(sc, "\n");
1419 		goto checkaddr;
1420 	case SIOCDIFPHYADDR:
1421 		GRE_DPRINTF(sc, "\n");
1422 		gre_clearconf(sp, true);
1423 		ifp->if_flags &= ~IFF_UP;
1424 		goto mksocket;
1425 	case SIOCGLIFPHYADDR:
1426 		GRE_DPRINTF(sc, "\n");
1427 		if (gre_is_nullconf(sp)) {
1428 			error = EADDRNOTAVAIL;
1429 			break;
1430 		}
1431 		sockaddr_copy(sstosa(&lifr->addr), sizeof(lifr->addr),
1432 		    sstosa(&sp->sp_src));
1433 		sockaddr_copy(sstosa(&lifr->dstaddr), sizeof(lifr->dstaddr),
1434 		    sstosa(&sp->sp_dst));
1435 		GRE_DPRINTF(sc, "\n");
1436 		break;
1437 	default:
1438 		error = ifioctl_common(ifp, cmd, data);
1439 		break;
1440 	}
1441 out:
1442 	GRE_DPRINTF(sc, "\n");
1443 	splx(s);
1444 	return error;
1445 }
1446 
1447 void	greattach(int);
1448 
1449 /* ARGSUSED */
1450 void
1451 greattach(int count)
1452 {
1453 	if_clone_attach(&gre_cloner);
1454 }
1455