xref: /netbsd-src/sys/net/if_gre.c (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*	$NetBSD: if_gre.c,v 1.153 2013/11/07 21:44:48 christos 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 1.153 2013/11/07 21:44:48 christos 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 	int fd, rc;
416 	struct mbuf *m;
417 	struct sockaddr *sa;
418 	struct socket *so;
419 	sa_family_t af;
420 	int val;
421 
422 	GRE_DPRINTF(sc, "enter\n");
423 
424 	af = sp->sp_src.ss_family;
425 	rc = fsocreate(af, NULL, sp->sp_type, sp->sp_proto, curlwp, &fd);
426 	if (rc != 0) {
427 		GRE_DPRINTF(sc, "fsocreate failed\n");
428 		return rc;
429 	}
430 
431 	if ((rc = fd_getsock(fd, &so)) != 0)
432 		return rc;
433 
434 	if ((m = getsombuf(so, MT_SONAME)) == NULL) {
435 		rc = ENOBUFS;
436 		goto out;
437 	}
438 	sa = mtod(m, struct sockaddr *);
439 	sockaddr_copy(sa, MIN(MLEN, sizeof(sp->sp_src)), sstocsa(&sp->sp_src));
440 	m->m_len = sp->sp_src.ss_len;
441 
442 	if ((rc = sobind(so, m, curlwp)) != 0) {
443 		GRE_DPRINTF(sc, "sobind failed\n");
444 		goto out;
445 	}
446 
447 	sockaddr_copy(sa, MIN(MLEN, sizeof(sp->sp_dst)), sstocsa(&sp->sp_dst));
448 	m->m_len = sp->sp_dst.ss_len;
449 
450 	solock(so);
451 	if ((rc = soconnect(so, m, curlwp)) != 0) {
452 		GRE_DPRINTF(sc, "soconnect failed\n");
453 		sounlock(so);
454 		goto out;
455 	}
456 	sounlock(so);
457 
458 	m = NULL;
459 
460 	/* XXX convert to a (new) SOL_SOCKET call */
461   	KASSERT(so->so_proto != NULL);
462  	rc = so_setsockopt(curlwp, so, IPPROTO_IP, IP_TTL,
463 	    &ip_gre_ttl, sizeof(ip_gre_ttl));
464   	if (rc != 0) {
465  		GRE_DPRINTF(sc, "so_setsockopt ttl failed\n");
466   		rc = 0;
467   	}
468 
469  	val = 1;
470  	rc = so_setsockopt(curlwp, so, SOL_SOCKET, SO_NOHEADER,
471 	    &val, sizeof(val));
472   	if (rc != 0) {
473  		GRE_DPRINTF(sc, "so_setsockopt SO_NOHEADER failed\n");
474 		rc = 0;
475 	}
476 out:
477 	m_freem(m);
478 
479 	if (rc != 0)
480 		fd_close(fd);
481 	else  {
482 		fd_putfile(fd);
483 		*fdout = fd;
484 	}
485 
486 	return rc;
487 }
488 
489 static int
490 gre_sosend(struct socket *so, struct mbuf *top)
491 {
492 	struct proc	*p;
493 	long		space, resid;
494 	int		error;
495 	struct lwp * const l = curlwp;
496 
497 	p = l->l_proc;
498 
499 	resid = top->m_pkthdr.len;
500 	if (p)
501 		l->l_ru.ru_msgsnd++;
502 #define	snderr(errno)	{ error = errno; goto release; }
503 
504 	solock(so);
505 	if ((error = sblock(&so->so_snd, M_NOWAIT)) != 0)
506 		goto out;
507 	if (so->so_state & SS_CANTSENDMORE)
508 		snderr(EPIPE);
509 	if (so->so_error) {
510 		error = so->so_error;
511 		so->so_error = 0;
512 		goto release;
513 	}
514 	if ((so->so_state & SS_ISCONNECTED) == 0) {
515 		if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
516 			snderr(ENOTCONN);
517 		} else {
518 			snderr(EDESTADDRREQ);
519 		}
520 	}
521 	space = sbspace(&so->so_snd);
522 	if (resid > so->so_snd.sb_hiwat)
523 		snderr(EMSGSIZE);
524 	if (space < resid)
525 		snderr(EWOULDBLOCK);
526 	/*
527 	 * Data is prepackaged in "top".
528 	 */
529 	if (so->so_state & SS_CANTSENDMORE)
530 		snderr(EPIPE);
531 	error = (*so->so_proto->pr_usrreq)(so, PRU_SEND, top, NULL, NULL, l);
532 	top = NULL;
533  release:
534 	sbunlock(&so->so_snd);
535  out:
536  	sounlock(so);
537 	if (top != NULL)
538 		m_freem(top);
539 	return error;
540 }
541 
542 /* This is a stripped-down version of soreceive() that will never
543  * block.  It will support SOCK_DGRAM sockets.  It may also support
544  * SOCK_SEQPACKET sockets.
545  */
546 static int
547 gre_soreceive(struct socket *so, struct mbuf **mp0)
548 {
549 	struct mbuf *m, **mp;
550 	int flags, len, error, type;
551 	const struct protosw	*pr;
552 	struct mbuf *nextrecord;
553 
554 	KASSERT(mp0 != NULL);
555 
556 	flags = MSG_DONTWAIT;
557 	pr = so->so_proto;
558 	mp = mp0;
559 	type = 0;
560 
561 	*mp = NULL;
562 
563 	KASSERT(pr->pr_flags & PR_ATOMIC);
564  restart:
565 	if ((error = sblock(&so->so_rcv, M_NOWAIT)) != 0) {
566 		return error;
567 	}
568 	m = so->so_rcv.sb_mb;
569 	/*
570 	 * If we have less data than requested, do not block awaiting more.
571 	 */
572 	if (m == NULL) {
573 #ifdef DIAGNOSTIC
574 		if (so->so_rcv.sb_cc)
575 			panic("receive 1");
576 #endif
577 		if (so->so_error) {
578 			error = so->so_error;
579 			so->so_error = 0;
580 		} else if (so->so_state & SS_CANTRCVMORE)
581 			;
582 		else if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0
583 		      && (so->so_proto->pr_flags & PR_CONNREQUIRED))
584 			error = ENOTCONN;
585 		else
586 			error = EWOULDBLOCK;
587 		goto release;
588 	}
589 	/*
590 	 * On entry here, m points to the first record of the socket buffer.
591 	 * While we process the initial mbufs containing address and control
592 	 * info, we save a copy of m->m_nextpkt into nextrecord.
593 	 */
594 	if (curlwp != NULL)
595 		curlwp->l_ru.ru_msgrcv++;
596 	KASSERT(m == so->so_rcv.sb_mb);
597 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 1");
598 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 1");
599 	nextrecord = m->m_nextpkt;
600 	if (pr->pr_flags & PR_ADDR) {
601 #ifdef DIAGNOSTIC
602 		if (m->m_type != MT_SONAME)
603 			panic("receive 1a");
604 #endif
605 		sbfree(&so->so_rcv, m);
606 		MFREE(m, so->so_rcv.sb_mb);
607 		m = so->so_rcv.sb_mb;
608 	}
609 	while (m != NULL && m->m_type == MT_CONTROL && error == 0) {
610 		sbfree(&so->so_rcv, m);
611 		/*
612 		 * Dispose of any SCM_RIGHTS message that went
613 		 * through the read path rather than recv.
614 		 */
615 		if (pr->pr_domain->dom_dispose &&
616 		    mtod(m, struct cmsghdr *)->cmsg_type == SCM_RIGHTS)
617 			(*pr->pr_domain->dom_dispose)(m);
618 		MFREE(m, so->so_rcv.sb_mb);
619 		m = so->so_rcv.sb_mb;
620 	}
621 
622 	/*
623 	 * If m is non-NULL, we have some data to read.  From now on,
624 	 * make sure to keep sb_lastrecord consistent when working on
625 	 * the last packet on the chain (nextrecord == NULL) and we
626 	 * change m->m_nextpkt.
627 	 */
628 	if (m != NULL) {
629 		m->m_nextpkt = nextrecord;
630 		/*
631 		 * If nextrecord == NULL (this is a single chain),
632 		 * then sb_lastrecord may not be valid here if m
633 		 * was changed earlier.
634 		 */
635 		if (nextrecord == NULL) {
636 			KASSERT(so->so_rcv.sb_mb == m);
637 			so->so_rcv.sb_lastrecord = m;
638 		}
639 		type = m->m_type;
640 		if (type == MT_OOBDATA)
641 			flags |= MSG_OOB;
642 	} else {
643 		KASSERT(so->so_rcv.sb_mb == m);
644 		so->so_rcv.sb_mb = nextrecord;
645 		SB_EMPTY_FIXUP(&so->so_rcv);
646 	}
647 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 2");
648 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 2");
649 
650 	while (m != NULL) {
651 		if (m->m_type == MT_OOBDATA) {
652 			if (type != MT_OOBDATA)
653 				break;
654 		} else if (type == MT_OOBDATA)
655 			break;
656 #ifdef DIAGNOSTIC
657 		else if (m->m_type != MT_DATA && m->m_type != MT_HEADER)
658 			panic("receive 3");
659 #endif
660 		so->so_state &= ~SS_RCVATMARK;
661 		if (so->so_oobmark != 0 && so->so_oobmark < m->m_len)
662 			break;
663 		len = m->m_len;
664 		/*
665 		 * mp is set, just pass back the mbufs.
666 		 * Sockbuf must be consistent here (points to current mbuf,
667 		 * it points to next record) when we drop priority;
668 		 * we must note any additions to the sockbuf when we
669 		 * block interrupts again.
670 		 */
671 		if (m->m_flags & M_EOR)
672 			flags |= MSG_EOR;
673 		nextrecord = m->m_nextpkt;
674 		sbfree(&so->so_rcv, m);
675 		*mp = m;
676 		mp = &m->m_next;
677 		so->so_rcv.sb_mb = m = m->m_next;
678 		*mp = NULL;
679 		/*
680 		 * If m != NULL, we also know that
681 		 * so->so_rcv.sb_mb != NULL.
682 		 */
683 		KASSERT(so->so_rcv.sb_mb == m);
684 		if (m) {
685 			m->m_nextpkt = nextrecord;
686 			if (nextrecord == NULL)
687 				so->so_rcv.sb_lastrecord = m;
688 		} else {
689 			so->so_rcv.sb_mb = nextrecord;
690 			SB_EMPTY_FIXUP(&so->so_rcv);
691 		}
692 		SBLASTRECORDCHK(&so->so_rcv, "soreceive 3");
693 		SBLASTMBUFCHK(&so->so_rcv, "soreceive 3");
694 		if (so->so_oobmark) {
695 			so->so_oobmark -= len;
696 			if (so->so_oobmark == 0) {
697 				so->so_state |= SS_RCVATMARK;
698 				break;
699 			}
700 		}
701 		if (flags & MSG_EOR)
702 			break;
703 	}
704 
705 	if (m != NULL) {
706 		m_freem(*mp);
707 		*mp = NULL;
708 		error = ENOMEM;
709 		(void) sbdroprecord(&so->so_rcv);
710 	} else {
711 		/*
712 		 * First part is an inline SB_EMPTY_FIXUP().  Second
713 		 * part makes sure sb_lastrecord is up-to-date if
714 		 * there is still data in the socket buffer.
715 		 */
716 		so->so_rcv.sb_mb = nextrecord;
717 		if (so->so_rcv.sb_mb == NULL) {
718 			so->so_rcv.sb_mbtail = NULL;
719 			so->so_rcv.sb_lastrecord = NULL;
720 		} else if (nextrecord->m_nextpkt == NULL)
721 			so->so_rcv.sb_lastrecord = nextrecord;
722 	}
723 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 4");
724 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 4");
725 	if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
726 		(*pr->pr_usrreq)(so, PRU_RCVD, NULL,
727 		    (struct mbuf *)(long)flags, NULL, curlwp);
728 	if (*mp0 == NULL && (flags & MSG_EOR) == 0 &&
729 	    (so->so_state & SS_CANTRCVMORE) == 0) {
730 		sbunlock(&so->so_rcv);
731 		goto restart;
732 	}
733 
734  release:
735 	sbunlock(&so->so_rcv);
736 	return error;
737 }
738 
739 static struct socket *
740 gre_reconf(struct gre_softc *sc, const struct gre_soparm *newsoparm)
741 {
742 	struct ifnet *ifp = &sc->sc_if;
743 
744 	GRE_DPRINTF(sc, "enter\n");
745 
746 shutdown:
747 	if (sc->sc_soparm.sp_so != NULL) {
748 		GRE_DPRINTF(sc, "\n");
749 		gre_upcall_remove(sc->sc_soparm.sp_so);
750 		softint_disestablish(sc->sc_si);
751 		sc->sc_si = NULL;
752 		gre_fp_send(sc, GRE_M_DELFP, NULL);
753 		gre_clearconf(&sc->sc_soparm, false);
754 	}
755 
756 	if (newsoparm != NULL) {
757 		GRE_DPRINTF(sc, "\n");
758 		sc->sc_soparm = *newsoparm;
759 		newsoparm = NULL;
760 	}
761 
762 	if (sc->sc_soparm.sp_so != NULL) {
763 		GRE_DPRINTF(sc, "\n");
764 		sc->sc_si = softint_establish(SOFTINT_NET, greintr, sc);
765 		gre_upcall_add(sc->sc_soparm.sp_so, sc);
766 		if ((ifp->if_flags & IFF_UP) == 0) {
767 			GRE_DPRINTF(sc, "down\n");
768 			goto shutdown;
769 		}
770 	}
771 
772 	GRE_DPRINTF(sc, "\n");
773 	if (sc->sc_soparm.sp_so != NULL)
774 		sc->sc_if.if_flags |= IFF_RUNNING;
775 	else {
776 		gre_bufq_purge(&sc->sc_snd);
777 		sc->sc_if.if_flags &= ~IFF_RUNNING;
778 	}
779 	return sc->sc_soparm.sp_so;
780 }
781 
782 static int
783 gre_input(struct gre_softc *sc, struct mbuf *m, int hlen,
784     const struct gre_h *gh)
785 {
786 	uint16_t flags;
787 	uint32_t af;		/* af passed to BPF tap */
788 	int isr, s;
789 	struct ifqueue *ifq;
790 
791 	sc->sc_if.if_ipackets++;
792 	sc->sc_if.if_ibytes += m->m_pkthdr.len;
793 
794 	hlen += sizeof(struct gre_h);
795 
796 	/* process GRE flags as packet can be of variable len */
797 	flags = ntohs(gh->flags);
798 
799 	/* Checksum & Offset are present */
800 	if ((flags & GRE_CP) | (flags & GRE_RP))
801 		hlen += 4;
802 	/* We don't support routing fields (variable length) */
803 	if (flags & GRE_RP) {
804 		sc->sc_if.if_ierrors++;
805 		return 0;
806 	}
807 	if (flags & GRE_KP)
808 		hlen += 4;
809 	if (flags & GRE_SP)
810 		hlen += 4;
811 
812 	switch (ntohs(gh->ptype)) { /* ethertypes */
813 #ifdef INET
814 	case ETHERTYPE_IP:
815 		ifq = &ipintrq;
816 		isr = NETISR_IP;
817 		af = AF_INET;
818 		break;
819 #endif
820 #ifdef NETATALK
821 	case ETHERTYPE_ATALK:
822 		ifq = &atintrq1;
823 		isr = NETISR_ATALK;
824 		af = AF_APPLETALK;
825 		break;
826 #endif
827 #ifdef INET6
828 	case ETHERTYPE_IPV6:
829 		ifq = &ip6intrq;
830 		isr = NETISR_IPV6;
831 		af = AF_INET6;
832 		break;
833 #endif
834 #ifdef MPLS
835 	case ETHERTYPE_MPLS:
836 		ifq = &mplsintrq;
837 		isr = NETISR_MPLS;
838 		af = AF_MPLS;
839 		break;
840 #endif
841 	default:	   /* others not yet supported */
842 		GRE_DPRINTF(sc, "unhandled ethertype 0x%04x\n",
843 		    ntohs(gh->ptype));
844 		sc->sc_if.if_noproto++;
845 		return 0;
846 	}
847 
848 	if (hlen > m->m_pkthdr.len) {
849 		m_freem(m);
850 		sc->sc_if.if_ierrors++;
851 		return EINVAL;
852 	}
853 	m_adj(m, hlen);
854 
855 	bpf_mtap_af(&sc->sc_if, af, m);
856 
857 	m->m_pkthdr.rcvif = &sc->sc_if;
858 
859 	s = splnet();
860 	if (IF_QFULL(ifq)) {
861 		IF_DROP(ifq);
862 		m_freem(m);
863 	} else {
864 		IF_ENQUEUE(ifq, m);
865 	}
866 	/* we need schednetisr since the address family may change */
867 	schednetisr(isr);
868 	splx(s);
869 
870 	return 1;	/* packet is done, no further processing needed */
871 }
872 
873 /*
874  * The output routine. Takes a packet and encapsulates it in the protocol
875  * given by sc->sc_soparm.sp_proto. See also RFC 1701 and RFC 2004
876  */
877 static int
878 gre_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
879 	   struct rtentry *rt)
880 {
881 	int error = 0;
882 	struct gre_softc *sc = ifp->if_softc;
883 	struct gre_h *gh;
884 	uint16_t etype = 0;
885 
886 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) {
887 		m_freem(m);
888 		error = ENETDOWN;
889 		goto end;
890 	}
891 
892 	bpf_mtap_af(ifp, dst->sa_family, m);
893 
894 	m->m_flags &= ~(M_BCAST|M_MCAST);
895 
896 	GRE_DPRINTF(sc, "dst->sa_family=%d\n", dst->sa_family);
897 	switch (dst->sa_family) {
898 #ifdef INET
899 	case AF_INET:
900 		/* TBD Extract the IP ToS field and set the
901 		 * encapsulating protocol's ToS to suit.
902 		 */
903 		etype = htons(ETHERTYPE_IP);
904 		break;
905 #endif
906 #ifdef NETATALK
907 	case AF_APPLETALK:
908 		etype = htons(ETHERTYPE_ATALK);
909 		break;
910 #endif
911 #ifdef INET6
912 	case AF_INET6:
913 		etype = htons(ETHERTYPE_IPV6);
914 		break;
915 #endif
916 	default:
917 		IF_DROP(&ifp->if_snd);
918 		m_freem(m);
919 		error = EAFNOSUPPORT;
920 		goto end;
921 	}
922 
923 #ifdef MPLS
924 		if (rt != NULL && rt_gettag(rt) != NULL) {
925 			union mpls_shim msh;
926 			msh.s_addr = MPLS_GETSADDR(rt);
927 			if (msh.shim.label != MPLS_LABEL_IMPLNULL)
928 				etype = htons(ETHERTYPE_MPLS);
929 		}
930 #endif
931 
932 	M_PREPEND(m, sizeof(*gh), M_DONTWAIT);
933 
934 	if (m == NULL) {
935 		IF_DROP(&ifp->if_snd);
936 		error = ENOBUFS;
937 		goto end;
938 	}
939 
940 	gh = mtod(m, struct gre_h *);
941 	gh->flags = 0;
942 	gh->ptype = etype;
943 	/* XXX Need to handle IP ToS.  Look at how I handle IP TTL. */
944 
945 	ifp->if_opackets++;
946 	ifp->if_obytes += m->m_pkthdr.len;
947 
948 	/* Clear checksum-offload flags. */
949 	m->m_pkthdr.csum_flags = 0;
950 	m->m_pkthdr.csum_data = 0;
951 
952 	/* send it off */
953 	if ((error = gre_bufq_enqueue(&sc->sc_snd, m)) != 0) {
954 		sc->sc_oflow_ev.ev_count++;
955 		m_freem(m);
956 	} else
957 		softint_schedule(sc->sc_si);
958   end:
959 	if (error)
960 		ifp->if_oerrors++;
961 	return error;
962 }
963 
964 static int
965 gre_getname(struct socket *so, int req, struct mbuf *nam, struct lwp *l)
966 {
967 	return (*so->so_proto->pr_usrreq)(so, req, NULL, nam, NULL, l);
968 }
969 
970 static int
971 gre_getsockname(struct socket *so, struct mbuf *nam, struct lwp *l)
972 {
973 	return gre_getname(so, PRU_SOCKADDR, nam, l);
974 }
975 
976 static int
977 gre_getpeername(struct socket *so, struct mbuf *nam, struct lwp *l)
978 {
979 	return gre_getname(so, PRU_PEERADDR, nam, l);
980 }
981 
982 static int
983 gre_getnames(struct socket *so, struct lwp *l, struct sockaddr_storage *src,
984     struct sockaddr_storage *dst)
985 {
986 	struct mbuf *m;
987 	struct sockaddr_storage *ss;
988 	int rc;
989 
990 	if ((m = getsombuf(so, MT_SONAME)) == NULL)
991 		return ENOBUFS;
992 
993 	ss = mtod(m, struct sockaddr_storage *);
994 
995 	solock(so);
996 	if ((rc = gre_getsockname(so, m, l)) != 0)
997 		goto out;
998 	*src = *ss;
999 
1000 	if ((rc = gre_getpeername(so, m, l)) != 0)
1001 		goto out;
1002 	*dst = *ss;
1003 out:
1004 	sounlock(so);
1005 	m_freem(m);
1006 	return rc;
1007 }
1008 
1009 static void
1010 gre_fp_recvloop(void *arg)
1011 {
1012 	struct gre_softc *sc = arg;
1013 
1014 	mutex_enter(&sc->sc_mtx);
1015 	while (gre_fp_recv(sc))
1016 		;
1017 	mutex_exit(&sc->sc_mtx);
1018 	kthread_exit(0);
1019 }
1020 
1021 static bool
1022 gre_fp_recv(struct gre_softc *sc)
1023 {
1024 	int fd, ofd, rc;
1025 	file_t *fp;
1026 
1027 	fp = sc->sc_fp;
1028 	ofd = sc->sc_fd;
1029 	fd = -1;
1030 
1031 	switch (sc->sc_msg) {
1032 	case GRE_M_STOP:
1033 		cv_signal(&sc->sc_fp_condvar);
1034 		return false;
1035 	case GRE_M_SETFP:
1036 		mutex_exit(&sc->sc_mtx);
1037 		rc = fd_dup(fp, 0, &fd, 0);
1038 		mutex_enter(&sc->sc_mtx);
1039 		if (rc != 0) {
1040 			sc->sc_msg = GRE_M_ERR;
1041 			break;
1042 		}
1043 		/*FALLTHROUGH*/
1044 	case GRE_M_DELFP:
1045 		mutex_exit(&sc->sc_mtx);
1046 		if (ofd != -1 && fd_getfile(ofd) != NULL)
1047 			fd_close(ofd);
1048 		mutex_enter(&sc->sc_mtx);
1049 		sc->sc_fd = fd;
1050 		sc->sc_msg = GRE_M_OK;
1051 		break;
1052 	default:
1053 		gre_fp_wait(sc);
1054 		return true;
1055 	}
1056 	cv_signal(&sc->sc_fp_condvar);
1057 	return true;
1058 }
1059 
1060 static bool
1061 gre_fp_send(struct gre_softc *sc, enum gre_msg msg, file_t *fp)
1062 {
1063 	bool rc;
1064 
1065 	mutex_enter(&sc->sc_mtx);
1066 	while (sc->sc_msg != GRE_M_NONE)
1067 		gre_fp_wait(sc);
1068 	sc->sc_fp = fp;
1069 	sc->sc_msg = msg;
1070 	cv_signal(&sc->sc_fp_condvar);
1071 	while (sc->sc_msg != GRE_M_STOP && sc->sc_msg != GRE_M_OK &&
1072 	            sc->sc_msg != GRE_M_ERR)
1073 		gre_fp_wait(sc);
1074 	rc = (sc->sc_msg != GRE_M_ERR);
1075 	sc->sc_msg = GRE_M_NONE;
1076 	cv_signal(&sc->sc_fp_condvar);
1077 	mutex_exit(&sc->sc_mtx);
1078 	return rc;
1079 }
1080 
1081 static int
1082 gre_ssock(struct ifnet *ifp, struct gre_soparm *sp, int fd)
1083 {
1084 	int error = 0;
1085 	const struct protosw *pr;
1086 	file_t *fp;
1087 	struct gre_softc *sc = ifp->if_softc;
1088 	struct socket *so;
1089 	struct sockaddr_storage dst, src;
1090 
1091 	if ((fp = fd_getfile(fd)) == NULL)
1092 		return EBADF;
1093 	if (fp->f_type != DTYPE_SOCKET) {
1094 		fd_putfile(fd);
1095 		return ENOTSOCK;
1096 	}
1097 
1098 	GRE_DPRINTF(sc, "\n");
1099 
1100 	so = (struct socket *)fp->f_data;
1101 	pr = so->so_proto;
1102 
1103 	GRE_DPRINTF(sc, "type %d, proto %d\n", pr->pr_type, pr->pr_protocol);
1104 
1105 	if ((pr->pr_flags & PR_ATOMIC) == 0 ||
1106 	    (sp->sp_type != 0 && pr->pr_type != sp->sp_type) ||
1107 	    (sp->sp_proto != 0 && pr->pr_protocol != 0 &&
1108 	     pr->pr_protocol != sp->sp_proto)) {
1109 		error = EINVAL;
1110 		goto err;
1111 	}
1112 
1113 	GRE_DPRINTF(sc, "\n");
1114 
1115 	/* check address */
1116 	if ((error = gre_getnames(so, curlwp, &src, &dst)) != 0)
1117 		goto err;
1118 
1119 	GRE_DPRINTF(sc, "\n");
1120 
1121 	if (!gre_fp_send(sc, GRE_M_SETFP, fp)) {
1122 		error = EBUSY;
1123 		goto err;
1124 	}
1125 
1126 	GRE_DPRINTF(sc, "\n");
1127 
1128 	sp->sp_src = src;
1129 	sp->sp_dst = dst;
1130 
1131 	sp->sp_so = so;
1132 
1133 err:
1134 	fd_putfile(fd);
1135 	return error;
1136 }
1137 
1138 static bool
1139 sockaddr_is_anyaddr(const struct sockaddr *sa)
1140 {
1141 	socklen_t anylen, salen;
1142 	const void *anyaddr, *addr;
1143 
1144 	if ((anyaddr = sockaddr_anyaddr(sa, &anylen)) == NULL ||
1145 	    (addr = sockaddr_const_addr(sa, &salen)) == NULL)
1146 		return false;
1147 
1148 	if (salen > anylen)
1149 		return false;
1150 
1151 	return memcmp(anyaddr, addr, MIN(anylen, salen)) == 0;
1152 }
1153 
1154 static bool
1155 gre_is_nullconf(const struct gre_soparm *sp)
1156 {
1157 	return sockaddr_is_anyaddr(sstocsa(&sp->sp_src)) ||
1158 	       sockaddr_is_anyaddr(sstocsa(&sp->sp_dst));
1159 }
1160 
1161 static void
1162 gre_clearconf(struct gre_soparm *sp, bool force)
1163 {
1164 	if (sp->sp_bysock || force) {
1165 		sockaddr_copy(sstosa(&sp->sp_src), sizeof(sp->sp_src),
1166 		    sockaddr_any(sstosa(&sp->sp_src)));
1167 		sockaddr_copy(sstosa(&sp->sp_dst), sizeof(sp->sp_dst),
1168 		    sockaddr_any(sstosa(&sp->sp_dst)));
1169 		sp->sp_bysock = false;
1170 	}
1171 	sp->sp_so = NULL; /* XXX */
1172 }
1173 
1174 static int
1175 gre_ioctl(struct ifnet *ifp, const u_long cmd, void *data)
1176 {
1177 	struct ifreq *ifr;
1178 	struct if_laddrreq *lifr = (struct if_laddrreq *)data;
1179 	struct gre_softc *sc = ifp->if_softc;
1180 	struct gre_soparm *sp;
1181 	int fd, error = 0, oproto, otype, s;
1182 	struct gre_soparm sp0;
1183 
1184 	ifr = data;
1185 
1186 	GRE_DPRINTF(sc, "cmd %lu\n", cmd);
1187 
1188 	switch (cmd) {
1189 	case GRESPROTO:
1190 	case GRESADDRD:
1191 	case GRESADDRS:
1192 	case GRESSOCK:
1193 	case GREDSOCK:
1194 		if (kauth_authorize_network(curlwp->l_cred,
1195 		    KAUTH_NETWORK_INTERFACE,
1196 		    KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
1197 		    NULL) != 0)
1198 			return EPERM;
1199 		break;
1200 	default:
1201 		break;
1202 	}
1203 
1204 	s = splnet();
1205 
1206 	sp0 = sc->sc_soparm;
1207 	sp0.sp_so = NULL;
1208 	sp = &sp0;
1209 
1210 	GRE_DPRINTF(sc, "\n");
1211 
1212 	switch (cmd) {
1213 	case SIOCINITIFADDR:
1214 		GRE_DPRINTF(sc, "\n");
1215 		if ((ifp->if_flags & IFF_UP) != 0)
1216 			break;
1217 		gre_clearconf(sp, false);
1218 		ifp->if_flags |= IFF_UP;
1219 		goto mksocket;
1220 	case SIOCSIFFLAGS:
1221 		if ((error = ifioctl_common(ifp, cmd, data)) != 0)
1222 			break;
1223 		oproto = sp->sp_proto;
1224 		otype = sp->sp_type;
1225 		switch (ifr->ifr_flags & (IFF_LINK0|IFF_LINK2)) {
1226 		case IFF_LINK0|IFF_LINK2:
1227 			sp->sp_proto = IPPROTO_UDP;
1228 			sp->sp_type = SOCK_DGRAM;
1229 			break;
1230 		case IFF_LINK2:
1231 			sp->sp_proto = 0;
1232 			sp->sp_type = 0;
1233 			break;
1234 		case IFF_LINK0:
1235 			sp->sp_proto = IPPROTO_GRE;
1236 			sp->sp_type = SOCK_RAW;
1237 			break;
1238 		default:
1239 			GRE_DPRINTF(sc, "\n");
1240 			error = EINVAL;
1241 			goto out;
1242 		}
1243 		GRE_DPRINTF(sc, "\n");
1244 		gre_clearconf(sp, false);
1245 		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) ==
1246 		    (IFF_UP|IFF_RUNNING) &&
1247 		    (oproto == sp->sp_proto || sp->sp_proto == 0) &&
1248 		    (otype == sp->sp_type || sp->sp_type == 0))
1249 			break;
1250 		switch (sp->sp_proto) {
1251 		case IPPROTO_UDP:
1252 		case IPPROTO_GRE:
1253 			goto mksocket;
1254 		default:
1255 			break;
1256 		}
1257 		break;
1258 	case SIOCSIFMTU:
1259 		/* XXX determine MTU automatically by probing w/
1260 		 * XXX do-not-fragment packets?
1261 		 */
1262 		if (ifr->ifr_mtu < 576) {
1263 			error = EINVAL;
1264 			break;
1265 		}
1266 		/*FALLTHROUGH*/
1267 	case SIOCGIFMTU:
1268 		if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET)
1269 			error = 0;
1270 		break;
1271 	case SIOCADDMULTI:
1272 	case SIOCDELMULTI:
1273 		if (ifr == NULL) {
1274 			error = EAFNOSUPPORT;
1275 			break;
1276 		}
1277 		switch (ifreq_getaddr(cmd, ifr)->sa_family) {
1278 #ifdef INET
1279 		case AF_INET:
1280 			break;
1281 #endif
1282 #ifdef INET6
1283 		case AF_INET6:
1284 			break;
1285 #endif
1286 		default:
1287 			error = EAFNOSUPPORT;
1288 			break;
1289 		}
1290 		break;
1291 	case GRESPROTO:
1292 		gre_clearconf(sp, false);
1293 		oproto = sp->sp_proto;
1294 		otype = sp->sp_type;
1295 		sp->sp_proto = ifr->ifr_flags;
1296 		switch (sp->sp_proto) {
1297 		case IPPROTO_UDP:
1298 			ifp->if_flags |= IFF_LINK0|IFF_LINK2;
1299 			sp->sp_type = SOCK_DGRAM;
1300 			break;
1301 		case IPPROTO_GRE:
1302 			ifp->if_flags |= IFF_LINK0;
1303 			ifp->if_flags &= ~IFF_LINK2;
1304 			sp->sp_type = SOCK_RAW;
1305 			break;
1306 		case 0:
1307 			ifp->if_flags &= ~IFF_LINK0;
1308 			ifp->if_flags |= IFF_LINK2;
1309 			sp->sp_type = 0;
1310 			break;
1311 		default:
1312 			error = EPROTONOSUPPORT;
1313 			break;
1314 		}
1315 		if ((oproto == sp->sp_proto || sp->sp_proto == 0) &&
1316 		    (otype == sp->sp_type || sp->sp_type == 0))
1317 			break;
1318 		switch (sp->sp_proto) {
1319 		case IPPROTO_UDP:
1320 		case IPPROTO_GRE:
1321 			goto mksocket;
1322 		default:
1323 			break;
1324 		}
1325 		break;
1326 	case GREGPROTO:
1327 		ifr->ifr_flags = sp->sp_proto;
1328 		break;
1329 	case GRESADDRS:
1330 	case GRESADDRD:
1331 		gre_clearconf(sp, false);
1332 		/* set tunnel endpoints and mark interface as up */
1333 		switch (cmd) {
1334 		case GRESADDRS:
1335 			sockaddr_copy(sstosa(&sp->sp_src),
1336 			    sizeof(sp->sp_src), ifreq_getaddr(cmd, ifr));
1337 			break;
1338 		case GRESADDRD:
1339 			sockaddr_copy(sstosa(&sp->sp_dst),
1340 			    sizeof(sp->sp_dst), ifreq_getaddr(cmd, ifr));
1341 			break;
1342 		}
1343 	checkaddr:
1344 		if (sockaddr_any(sstosa(&sp->sp_src)) == NULL ||
1345 		    sockaddr_any(sstosa(&sp->sp_dst)) == NULL) {
1346 			error = EINVAL;
1347 			break;
1348 		}
1349 		/* let gre_socreate() check the rest */
1350 	mksocket:
1351 		GRE_DPRINTF(sc, "\n");
1352 		/* If we're administratively down, or the configuration
1353 		 * is empty, there's no use creating a socket.
1354 		 */
1355 		if ((ifp->if_flags & IFF_UP) == 0 || gre_is_nullconf(sp))
1356 			goto sendconf;
1357 
1358 		GRE_DPRINTF(sc, "\n");
1359 		fd = 0;
1360 		error = gre_socreate(sc, sp, &fd);
1361 		if (error != 0)
1362 			break;
1363 
1364 	setsock:
1365 		GRE_DPRINTF(sc, "\n");
1366 
1367 		error = gre_ssock(ifp, sp, fd);
1368 
1369 		if (cmd != GRESSOCK) {
1370 			GRE_DPRINTF(sc, "\n");
1371 			/* XXX v. dodgy */
1372 			if (fd_getfile(fd) != NULL)
1373 				fd_close(fd);
1374 		}
1375 
1376 		if (error == 0) {
1377 	sendconf:
1378 			GRE_DPRINTF(sc, "\n");
1379 			ifp->if_flags &= ~IFF_RUNNING;
1380 			gre_reconf(sc, sp);
1381 		}
1382 
1383 		break;
1384 	case GREGADDRS:
1385 		ifreq_setaddr(cmd, ifr, sstosa(&sp->sp_src));
1386 		break;
1387 	case GREGADDRD:
1388 		ifreq_setaddr(cmd, ifr, sstosa(&sp->sp_dst));
1389 		break;
1390 	case GREDSOCK:
1391 		GRE_DPRINTF(sc, "\n");
1392 		if (sp->sp_bysock)
1393 			ifp->if_flags &= ~IFF_UP;
1394 		gre_clearconf(sp, false);
1395 		goto mksocket;
1396 	case GRESSOCK:
1397 		GRE_DPRINTF(sc, "\n");
1398 		gre_clearconf(sp, true);
1399 		fd = (int)ifr->ifr_value;
1400 		sp->sp_bysock = true;
1401 		ifp->if_flags |= IFF_UP;
1402 		goto setsock;
1403 	case SIOCSLIFPHYADDR:
1404 		GRE_DPRINTF(sc, "\n");
1405 		if (lifr->addr.ss_family != lifr->dstaddr.ss_family) {
1406 			error = EAFNOSUPPORT;
1407 			break;
1408 		}
1409 		sockaddr_copy(sstosa(&sp->sp_src), sizeof(sp->sp_src),
1410 		    sstosa(&lifr->addr));
1411 		sockaddr_copy(sstosa(&sp->sp_dst), sizeof(sp->sp_dst),
1412 		    sstosa(&lifr->dstaddr));
1413 		GRE_DPRINTF(sc, "\n");
1414 		goto checkaddr;
1415 	case SIOCDIFPHYADDR:
1416 		GRE_DPRINTF(sc, "\n");
1417 		gre_clearconf(sp, true);
1418 		ifp->if_flags &= ~IFF_UP;
1419 		goto mksocket;
1420 	case SIOCGLIFPHYADDR:
1421 		GRE_DPRINTF(sc, "\n");
1422 		if (gre_is_nullconf(sp)) {
1423 			error = EADDRNOTAVAIL;
1424 			break;
1425 		}
1426 		sockaddr_copy(sstosa(&lifr->addr), sizeof(lifr->addr),
1427 		    sstosa(&sp->sp_src));
1428 		sockaddr_copy(sstosa(&lifr->dstaddr), sizeof(lifr->dstaddr),
1429 		    sstosa(&sp->sp_dst));
1430 		GRE_DPRINTF(sc, "\n");
1431 		break;
1432 	default:
1433 		error = ifioctl_common(ifp, cmd, data);
1434 		break;
1435 	}
1436 out:
1437 	GRE_DPRINTF(sc, "\n");
1438 	splx(s);
1439 	return error;
1440 }
1441 
1442 void	greattach(int);
1443 
1444 /* ARGSUSED */
1445 void
1446 greattach(int count)
1447 {
1448 	if_clone_attach(&gre_cloner);
1449 }
1450