xref: /netbsd-src/sys/net/if_gre.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: if_gre.c,v 1.173 2018/06/26 06:48:02 msaitoh 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 1.173 2018/06/26 06:48:02 msaitoh Exp $");
49 
50 #ifdef _KERNEL_OPT
51 #include "opt_atalk.h"
52 #include "opt_gre.h"
53 #include "opt_inet.h"
54 #include "opt_mpls.h"
55 #endif
56 
57 #include <sys/param.h>
58 #include <sys/file.h>
59 #include <sys/filedesc.h>
60 #include <sys/malloc.h>
61 #include <sys/mallocvar.h>
62 #include <sys/mbuf.h>
63 #include <sys/proc.h>
64 #include <sys/domain.h>
65 #include <sys/protosw.h>
66 #include <sys/socket.h>
67 #include <sys/socketvar.h>
68 #include <sys/ioctl.h>
69 #include <sys/queue.h>
70 #include <sys/intr.h>
71 #include <sys/systm.h>
72 #include <sys/sysctl.h>
73 #include <sys/kauth.h>
74 #include <sys/device.h>
75 #include <sys/module.h>
76 
77 #include <sys/kernel.h>
78 #include <sys/mutex.h>
79 #include <sys/condvar.h>
80 #include <sys/kthread.h>
81 
82 #include <sys/cpu.h>
83 
84 #include <net/ethertypes.h>
85 #include <net/if.h>
86 #include <net/if_types.h>
87 #include <net/netisr.h>
88 #include <net/route.h>
89 #include <sys/device.h>
90 #include <sys/module.h>
91 #include <sys/atomic.h>
92 
93 #include <netinet/in_systm.h>
94 #include <netinet/in.h>
95 #include <netinet/ip.h> /* we always need this for sizeof(struct ip) */
96 
97 #ifdef INET
98 #include <netinet/in_var.h>
99 #include <netinet/ip_var.h>
100 #endif
101 
102 #ifdef INET6
103 #include <netinet6/in6_var.h>
104 #endif
105 
106 #ifdef MPLS
107 #include <netmpls/mpls.h>
108 #include <netmpls/mpls_var.h>
109 #endif
110 
111 #ifdef NETATALK
112 #include <netatalk/at.h>
113 #include <netatalk/at_var.h>
114 #include <netatalk/at_extern.h>
115 #endif
116 
117 #include <sys/time.h>
118 #include <net/bpf.h>
119 
120 #include <net/if_gre.h>
121 
122 #include <compat/sys/socket.h>
123 #include <compat/sys/sockio.h>
124 
125 #include "ioconf.h"
126 
127 /*
128  * It is not easy to calculate the right value for a GRE MTU.
129  * We leave this task to the admin and use the same default that
130  * other vendors use.
131  */
132 #define GREMTU 1476
133 
134 #ifdef GRE_DEBUG
135 int gre_debug = 0;
136 #define	GRE_DPRINTF(__sc, ...)						\
137 	do {								\
138 		if (__predict_false(gre_debug ||			\
139 		    ((__sc)->sc_if.if_flags & IFF_DEBUG) != 0)) {	\
140 			printf("%s.%d: ", __func__, __LINE__);		\
141 			printf(__VA_ARGS__);				\
142 		}							\
143 	} while (/*CONSTCOND*/0)
144 #else
145 #define	GRE_DPRINTF(__sc, __fmt, ...)	do { } while (/*CONSTCOND*/0)
146 #endif /* GRE_DEBUG */
147 
148 int ip_gre_ttl = GRE_TTL;
149 
150 static u_int gre_count;
151 
152 static int gre_clone_create(struct if_clone *, int);
153 static int gre_clone_destroy(struct ifnet *);
154 
155 static struct if_clone gre_cloner =
156     IF_CLONE_INITIALIZER("gre", gre_clone_create, gre_clone_destroy);
157 
158 static int gre_input(struct gre_softc *, struct mbuf *, const struct gre_h *);
159 static bool gre_is_nullconf(const struct gre_soparm *);
160 static int gre_output(struct ifnet *, struct mbuf *,
161 			   const struct sockaddr *, const struct rtentry *);
162 static int gre_ioctl(struct ifnet *, u_long, void *);
163 static int gre_getsockname(struct socket *, struct sockaddr *);
164 static int gre_getpeername(struct socket *, struct sockaddr *);
165 static int gre_getnames(struct socket *, struct lwp *,
166     struct sockaddr_storage *, struct sockaddr_storage *);
167 static void gre_clearconf(struct gre_soparm *, bool);
168 static int gre_soreceive(struct socket *, struct mbuf **);
169 static int gre_sosend(struct socket *, struct mbuf *);
170 static struct socket *gre_reconf(struct gre_softc *, const struct gre_soparm *);
171 
172 static bool gre_fp_send(struct gre_softc *, enum gre_msg, file_t *);
173 static bool gre_fp_recv(struct gre_softc *);
174 static void gre_fp_recvloop(void *);
175 
176 static void
177 gre_bufq_init(struct gre_bufq *bq, size_t len0)
178 {
179 	memset(bq, 0, sizeof(*bq));
180 	bq->bq_q = pcq_create(len0, KM_SLEEP);
181 	KASSERT(bq->bq_q != NULL);
182 }
183 
184 static struct mbuf *
185 gre_bufq_dequeue(struct gre_bufq *bq)
186 {
187 	return pcq_get(bq->bq_q);
188 }
189 
190 static void
191 gre_bufq_purge(struct gre_bufq *bq)
192 {
193 	struct mbuf *m;
194 
195 	while ((m = gre_bufq_dequeue(bq)) != NULL)
196 		m_freem(m);
197 }
198 
199 static void
200 gre_bufq_destroy(struct gre_bufq *bq)
201 {
202 	gre_bufq_purge(bq);
203 	pcq_destroy(bq->bq_q);
204 }
205 
206 static int
207 gre_bufq_enqueue(struct gre_bufq *bq, struct mbuf *m)
208 {
209 	KASSERT(bq->bq_q != NULL);
210 
211 	if (!pcq_put(bq->bq_q, m)) {
212 		bq->bq_drops++;
213 		return ENOBUFS;
214 	}
215 	return 0;
216 }
217 
218 static void
219 greintr(void *arg)
220 {
221 	struct gre_softc *sc = (struct gre_softc *)arg;
222 	struct socket *so = sc->sc_soparm.sp_so;
223 	int rc;
224 	struct mbuf *m;
225 
226 	KASSERT(so != NULL);
227 
228 	sc->sc_send_ev.ev_count++;
229 	GRE_DPRINTF(sc, "enter\n");
230 	while ((m = gre_bufq_dequeue(&sc->sc_snd)) != NULL) {
231 		/* XXX handle ENOBUFS? */
232 		if ((rc = gre_sosend(so, m)) != 0)
233 			GRE_DPRINTF(sc, "gre_sosend failed %d\n", rc);
234 	}
235 }
236 
237 /* Caller must hold sc->sc_mtx. */
238 static void
239 gre_fp_wait(struct gre_softc *sc)
240 {
241 	sc->sc_fp_waiters++;
242 	cv_wait(&sc->sc_fp_condvar, &sc->sc_mtx);
243 	sc->sc_fp_waiters--;
244 }
245 
246 static void
247 gre_evcnt_detach(struct gre_softc *sc)
248 {
249 	evcnt_detach(&sc->sc_recv_ev);
250 	evcnt_detach(&sc->sc_block_ev);
251 	evcnt_detach(&sc->sc_error_ev);
252 	evcnt_detach(&sc->sc_pullup_ev);
253 	evcnt_detach(&sc->sc_unsupp_ev);
254 
255 	evcnt_detach(&sc->sc_send_ev);
256 	evcnt_detach(&sc->sc_oflow_ev);
257 }
258 
259 static void
260 gre_evcnt_attach(struct gre_softc *sc)
261 {
262 	evcnt_attach_dynamic(&sc->sc_recv_ev, EVCNT_TYPE_MISC,
263 	    NULL, sc->sc_if.if_xname, "recv");
264 	evcnt_attach_dynamic(&sc->sc_block_ev, EVCNT_TYPE_MISC,
265 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "would block");
266 	evcnt_attach_dynamic(&sc->sc_error_ev, EVCNT_TYPE_MISC,
267 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "error");
268 	evcnt_attach_dynamic(&sc->sc_pullup_ev, EVCNT_TYPE_MISC,
269 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "pullup failed");
270 	evcnt_attach_dynamic(&sc->sc_unsupp_ev, EVCNT_TYPE_MISC,
271 	    &sc->sc_recv_ev, sc->sc_if.if_xname, "unsupported");
272 
273 	evcnt_attach_dynamic(&sc->sc_send_ev, EVCNT_TYPE_MISC,
274 	    NULL, sc->sc_if.if_xname, "send");
275 	evcnt_attach_dynamic(&sc->sc_oflow_ev, EVCNT_TYPE_MISC,
276 	    &sc->sc_send_ev, sc->sc_if.if_xname, "overflow");
277 }
278 
279 static int
280 gre_clone_create(struct if_clone *ifc, int unit)
281 {
282 	int rc;
283 	struct gre_softc *sc;
284 	struct gre_soparm *sp;
285 	const struct sockaddr *any;
286 
287 	if ((any = sockaddr_any_by_family(AF_INET)) == NULL &&
288 	    (any = sockaddr_any_by_family(AF_INET6)) == NULL)
289 		goto fail0;
290 
291 	sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK|M_ZERO);
292 	mutex_init(&sc->sc_mtx, MUTEX_DRIVER, IPL_SOFTNET);
293 	cv_init(&sc->sc_condvar, "gre wait");
294 	cv_init(&sc->sc_fp_condvar, "gre fp");
295 
296 	if_initname(&sc->sc_if, ifc->ifc_name, unit);
297 	sc->sc_if.if_softc = sc;
298 	sc->sc_if.if_type = IFT_TUNNEL;
299 	sc->sc_if.if_addrlen = 0;
300 	sc->sc_if.if_hdrlen = sizeof(struct ip) + sizeof(struct gre_h);
301 	sc->sc_if.if_dlt = DLT_NULL;
302 	sc->sc_if.if_mtu = GREMTU;
303 	sc->sc_if.if_flags = IFF_POINTOPOINT|IFF_MULTICAST;
304 	sc->sc_if.if_output = gre_output;
305 	sc->sc_if.if_ioctl = gre_ioctl;
306 	sp = &sc->sc_soparm;
307 	sockaddr_copy(sstosa(&sp->sp_dst), sizeof(sp->sp_dst), any);
308 	sockaddr_copy(sstosa(&sp->sp_src), sizeof(sp->sp_src), any);
309 	sp->sp_proto = IPPROTO_GRE;
310 	sp->sp_type = SOCK_RAW;
311 
312 	sc->sc_fd = -1;
313 
314 	rc = kthread_create(PRI_NONE, KTHREAD_MPSAFE, NULL, gre_fp_recvloop, sc,
315 	    NULL, "%s", sc->sc_if.if_xname);
316 	if (rc)
317 		goto fail1;
318 
319 	gre_evcnt_attach(sc);
320 
321 	gre_bufq_init(&sc->sc_snd, 17);
322 	sc->sc_if.if_flags |= IFF_LINK0;
323 	if_attach(&sc->sc_if);
324 	if_alloc_sadl(&sc->sc_if);
325 	bpf_attach(&sc->sc_if, DLT_NULL, sizeof(uint32_t));
326 	atomic_inc_uint(&gre_count);
327 	return 0;
328 
329 fail1:
330 	cv_destroy(&sc->sc_fp_condvar);
331 	cv_destroy(&sc->sc_condvar);
332 	mutex_destroy(&sc->sc_mtx);
333 	free(sc, M_DEVBUF);
334 
335 fail0:
336 	return -1;
337 }
338 
339 static int
340 gre_clone_destroy(struct ifnet *ifp)
341 {
342 	int s;
343 	struct gre_softc *sc = ifp->if_softc;
344 
345 	GRE_DPRINTF(sc, "\n");
346 
347 	bpf_detach(ifp);
348 	s = splnet();
349 	if_detach(ifp);
350 
351 	GRE_DPRINTF(sc, "\n");
352 	/* Note that we must not hold the mutex while we call gre_reconf(). */
353 	gre_reconf(sc, NULL);
354 
355 	mutex_enter(&sc->sc_mtx);
356 	sc->sc_msg = GRE_M_STOP;
357 	cv_signal(&sc->sc_fp_condvar);
358 	while (sc->sc_fp_waiters > 0)
359 		cv_wait(&sc->sc_fp_condvar, &sc->sc_mtx);
360 	mutex_exit(&sc->sc_mtx);
361 
362 	splx(s);
363 
364 	cv_destroy(&sc->sc_condvar);
365 	cv_destroy(&sc->sc_fp_condvar);
366 	mutex_destroy(&sc->sc_mtx);
367 	gre_bufq_destroy(&sc->sc_snd);
368 	gre_evcnt_detach(sc);
369 	free(sc, M_DEVBUF);
370 
371 	atomic_dec_uint(&gre_count);
372 	return 0;
373 }
374 
375 static void
376 gre_receive(struct socket *so, void *arg, int events, int waitflag)
377 {
378 	struct gre_softc *sc = (struct gre_softc *)arg;
379 	int rc;
380 	const struct gre_h *gh;
381 	struct mbuf *m;
382 
383 	GRE_DPRINTF(sc, "enter\n");
384 
385 	sc->sc_recv_ev.ev_count++;
386 
387 	rc = gre_soreceive(so, &m);
388 	/* TBD Back off if ECONNREFUSED (indicates
389 	 * ICMP Port Unreachable)?
390 	 */
391 	if (rc == EWOULDBLOCK) {
392 		GRE_DPRINTF(sc, "EWOULDBLOCK\n");
393 		sc->sc_block_ev.ev_count++;
394 		return;
395 	} else if (rc != 0 || m == NULL) {
396 		GRE_DPRINTF(sc, "%s: rc %d m %p\n",
397 		    sc->sc_if.if_xname, rc, (void *)m);
398 		sc->sc_error_ev.ev_count++;
399 		return;
400 	}
401 	if (m->m_len < sizeof(*gh) && (m = m_pullup(m, sizeof(*gh))) == NULL) {
402 		GRE_DPRINTF(sc, "m_pullup failed\n");
403 		sc->sc_pullup_ev.ev_count++;
404 		return;
405 	}
406 	gh = mtod(m, const struct gre_h *);
407 
408 	if (gre_input(sc, m, gh) == 0) {
409 		sc->sc_unsupp_ev.ev_count++;
410 		GRE_DPRINTF(sc, "dropping unsupported\n");
411 		m_freem(m);
412 	}
413 }
414 
415 static void
416 gre_upcall_add(struct socket *so, void *arg)
417 {
418 	/* XXX What if the kernel already set an upcall? */
419 	KASSERT((so->so_rcv.sb_flags & SB_UPCALL) == 0);
420 	so->so_upcallarg = arg;
421 	so->so_upcall = gre_receive;
422 	so->so_rcv.sb_flags |= SB_UPCALL;
423 }
424 
425 static void
426 gre_upcall_remove(struct socket *so)
427 {
428 	so->so_rcv.sb_flags &= ~SB_UPCALL;
429 	so->so_upcallarg = NULL;
430 	so->so_upcall = NULL;
431 }
432 
433 static int
434 gre_socreate(struct gre_softc *sc, const struct gre_soparm *sp, int *fdout)
435 {
436 	int fd, rc;
437 	struct socket *so;
438 	struct sockaddr_big sbig;
439 	sa_family_t af;
440 	int val;
441 
442 	GRE_DPRINTF(sc, "enter\n");
443 
444 	af = sp->sp_src.ss_family;
445 	rc = fsocreate(af, NULL, sp->sp_type, sp->sp_proto, &fd);
446 	if (rc != 0) {
447 		GRE_DPRINTF(sc, "fsocreate failed\n");
448 		return rc;
449 	}
450 
451 	if ((rc = fd_getsock(fd, &so)) != 0)
452 		return rc;
453 
454 	memcpy(&sbig, &sp->sp_src, sizeof(sp->sp_src));
455 	if ((rc = sobind(so, (struct sockaddr *)&sbig, curlwp)) != 0) {
456 		GRE_DPRINTF(sc, "sobind failed\n");
457 		goto out;
458 	}
459 
460 	memcpy(&sbig, &sp->sp_dst, sizeof(sp->sp_dst));
461 	solock(so);
462 	if ((rc = soconnect(so, (struct sockaddr *)&sbig, curlwp)) != 0) {
463 		GRE_DPRINTF(sc, "soconnect failed\n");
464 		sounlock(so);
465 		goto out;
466 	}
467 	sounlock(so);
468 
469 	/* XXX convert to a (new) SOL_SOCKET call */
470   	KASSERT(so->so_proto != NULL);
471  	rc = so_setsockopt(curlwp, so, IPPROTO_IP, IP_TTL,
472 	    &ip_gre_ttl, sizeof(ip_gre_ttl));
473   	if (rc != 0) {
474  		GRE_DPRINTF(sc, "so_setsockopt ttl failed\n");
475   		rc = 0;
476   	}
477 
478  	val = 1;
479  	rc = so_setsockopt(curlwp, so, SOL_SOCKET, SO_NOHEADER,
480 	    &val, sizeof(val));
481   	if (rc != 0) {
482  		GRE_DPRINTF(sc, "so_setsockopt SO_NOHEADER failed\n");
483 		rc = 0;
484 	}
485 out:
486 	if (rc != 0)
487 		fd_close(fd);
488 	else  {
489 		fd_putfile(fd);
490 		*fdout = fd;
491 	}
492 
493 	return rc;
494 }
495 
496 static int
497 gre_sosend(struct socket *so, struct mbuf *top)
498 {
499 	struct proc	*p;
500 	long		space, resid;
501 	int		error;
502 	struct lwp * const l = curlwp;
503 
504 	p = l->l_proc;
505 
506 	resid = top->m_pkthdr.len;
507 	if (p)
508 		l->l_ru.ru_msgsnd++;
509 #define	snderr(errno)	{ error = errno; goto release; }
510 
511 	solock(so);
512 	if ((error = sblock(&so->so_snd, M_NOWAIT)) != 0)
513 		goto out;
514 	if (so->so_state & SS_CANTSENDMORE)
515 		snderr(EPIPE);
516 	if (so->so_error) {
517 		error = so->so_error;
518 		so->so_error = 0;
519 		goto release;
520 	}
521 	if ((so->so_state & SS_ISCONNECTED) == 0) {
522 		if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
523 			snderr(ENOTCONN);
524 		} else {
525 			snderr(EDESTADDRREQ);
526 		}
527 	}
528 	space = sbspace(&so->so_snd);
529 	if (resid > so->so_snd.sb_hiwat)
530 		snderr(EMSGSIZE);
531 	if (space < resid)
532 		snderr(EWOULDBLOCK);
533 	/*
534 	 * Data is prepackaged in "top".
535 	 */
536 	if (so->so_state & SS_CANTSENDMORE)
537 		snderr(EPIPE);
538 	error = (*so->so_proto->pr_usrreqs->pr_send)(so,
539 	    top, NULL, NULL, l);
540 	top = NULL;
541  release:
542 	sbunlock(&so->so_snd);
543  out:
544  	sounlock(so);
545 	if (top != NULL)
546 		m_freem(top);
547 	return error;
548 }
549 
550 /* This is a stripped-down version of soreceive() that will never
551  * block.  It will support SOCK_DGRAM sockets.  It may also support
552  * SOCK_SEQPACKET sockets.
553  */
554 static int
555 gre_soreceive(struct socket *so, struct mbuf **mp0)
556 {
557 	struct mbuf *m, **mp;
558 	int flags, len, error, type;
559 	const struct protosw	*pr;
560 	struct mbuf *nextrecord;
561 
562 	KASSERT(mp0 != NULL);
563 
564 	flags = MSG_DONTWAIT;
565 	pr = so->so_proto;
566 	mp = mp0;
567 	type = 0;
568 
569 	*mp = NULL;
570 
571 	KASSERT(pr->pr_flags & PR_ATOMIC);
572  restart:
573 	if ((error = sblock(&so->so_rcv, M_NOWAIT)) != 0) {
574 		return error;
575 	}
576 	m = so->so_rcv.sb_mb;
577 	/*
578 	 * If we have less data than requested, do not block awaiting more.
579 	 */
580 	if (m == NULL) {
581 #ifdef DIAGNOSTIC
582 		if (so->so_rcv.sb_cc)
583 			panic("receive 1");
584 #endif
585 		if (so->so_error) {
586 			error = so->so_error;
587 			so->so_error = 0;
588 		} else if (so->so_state & SS_CANTRCVMORE)
589 			;
590 		else if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0
591 		      && (so->so_proto->pr_flags & PR_CONNREQUIRED))
592 			error = ENOTCONN;
593 		else
594 			error = EWOULDBLOCK;
595 		goto release;
596 	}
597 	/*
598 	 * On entry here, m points to the first record of the socket buffer.
599 	 * While we process the initial mbufs containing address and control
600 	 * info, we save a copy of m->m_nextpkt into nextrecord.
601 	 */
602 	if (curlwp != NULL)
603 		curlwp->l_ru.ru_msgrcv++;
604 	KASSERT(m == so->so_rcv.sb_mb);
605 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 1");
606 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 1");
607 	nextrecord = m->m_nextpkt;
608 	if (pr->pr_flags & PR_ADDR) {
609 #ifdef DIAGNOSTIC
610 		if (m->m_type != MT_SONAME)
611 			panic("receive 1a");
612 #endif
613 		sbfree(&so->so_rcv, m);
614 		m = so->so_rcv.sb_mb = m_free(m);
615 	}
616 	while (m != NULL && m->m_type == MT_CONTROL && error == 0) {
617 		sbfree(&so->so_rcv, m);
618 		/*
619 		 * Dispose of any SCM_RIGHTS message that went
620 		 * through the read path rather than recv.
621 		 */
622 		if (pr->pr_domain->dom_dispose &&
623 		    mtod(m, struct cmsghdr *)->cmsg_type == SCM_RIGHTS)
624 			(*pr->pr_domain->dom_dispose)(m);
625 		m = so->so_rcv.sb_mb = m_free(m);
626 	}
627 
628 	/*
629 	 * If m is non-NULL, we have some data to read.  From now on,
630 	 * make sure to keep sb_lastrecord consistent when working on
631 	 * the last packet on the chain (nextrecord == NULL) and we
632 	 * change m->m_nextpkt.
633 	 */
634 	if (m != NULL) {
635 		m->m_nextpkt = nextrecord;
636 		/*
637 		 * If nextrecord == NULL (this is a single chain),
638 		 * then sb_lastrecord may not be valid here if m
639 		 * was changed earlier.
640 		 */
641 		if (nextrecord == NULL) {
642 			KASSERT(so->so_rcv.sb_mb == m);
643 			so->so_rcv.sb_lastrecord = m;
644 		}
645 		type = m->m_type;
646 		if (type == MT_OOBDATA)
647 			flags |= MSG_OOB;
648 	} else {
649 		KASSERT(so->so_rcv.sb_mb == m);
650 		so->so_rcv.sb_mb = nextrecord;
651 		SB_EMPTY_FIXUP(&so->so_rcv);
652 	}
653 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 2");
654 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 2");
655 
656 	while (m != NULL) {
657 		if (m->m_type == MT_OOBDATA) {
658 			if (type != MT_OOBDATA)
659 				break;
660 		} else if (type == MT_OOBDATA)
661 			break;
662 #ifdef DIAGNOSTIC
663 		else if (m->m_type != MT_DATA && m->m_type != MT_HEADER)
664 			panic("receive 3");
665 #endif
666 		so->so_state &= ~SS_RCVATMARK;
667 		if (so->so_oobmark != 0 && so->so_oobmark < m->m_len)
668 			break;
669 		len = m->m_len;
670 		/*
671 		 * mp is set, just pass back the mbufs.
672 		 * Sockbuf must be consistent here (points to current mbuf,
673 		 * it points to next record) when we drop priority;
674 		 * we must note any additions to the sockbuf when we
675 		 * block interrupts again.
676 		 */
677 		if (m->m_flags & M_EOR)
678 			flags |= MSG_EOR;
679 		nextrecord = m->m_nextpkt;
680 		sbfree(&so->so_rcv, m);
681 		*mp = m;
682 		mp = &m->m_next;
683 		so->so_rcv.sb_mb = m = m->m_next;
684 		*mp = NULL;
685 		/*
686 		 * If m != NULL, we also know that
687 		 * so->so_rcv.sb_mb != NULL.
688 		 */
689 		KASSERT(so->so_rcv.sb_mb == m);
690 		if (m) {
691 			m->m_nextpkt = nextrecord;
692 			if (nextrecord == NULL)
693 				so->so_rcv.sb_lastrecord = m;
694 		} else {
695 			so->so_rcv.sb_mb = nextrecord;
696 			SB_EMPTY_FIXUP(&so->so_rcv);
697 		}
698 		SBLASTRECORDCHK(&so->so_rcv, "soreceive 3");
699 		SBLASTMBUFCHK(&so->so_rcv, "soreceive 3");
700 		if (so->so_oobmark) {
701 			so->so_oobmark -= len;
702 			if (so->so_oobmark == 0) {
703 				so->so_state |= SS_RCVATMARK;
704 				break;
705 			}
706 		}
707 		if (flags & MSG_EOR)
708 			break;
709 	}
710 
711 	if (m != NULL) {
712 		m_freem(*mp);
713 		*mp = NULL;
714 		error = ENOMEM;
715 		(void) sbdroprecord(&so->so_rcv);
716 	} else {
717 		/*
718 		 * First part is an inline SB_EMPTY_FIXUP().  Second
719 		 * part makes sure sb_lastrecord is up-to-date if
720 		 * there is still data in the socket buffer.
721 		 */
722 		so->so_rcv.sb_mb = nextrecord;
723 		if (so->so_rcv.sb_mb == NULL) {
724 			so->so_rcv.sb_mbtail = NULL;
725 			so->so_rcv.sb_lastrecord = NULL;
726 		} else if (nextrecord->m_nextpkt == NULL)
727 			so->so_rcv.sb_lastrecord = nextrecord;
728 	}
729 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 4");
730 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 4");
731 	if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
732 		(*pr->pr_usrreqs->pr_rcvd)(so, flags, 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, const struct gre_h *gh)
789 {
790 	pktqueue_t *pktq = NULL;
791 	struct ifqueue *ifq = NULL;
792 	uint16_t flags;
793 	uint32_t af;		/* af passed to BPF tap */
794 	int isr = 0, s;
795 	int hlen;
796 
797 	sc->sc_if.if_ipackets++;
798 	sc->sc_if.if_ibytes += m->m_pkthdr.len;
799 
800 	hlen = sizeof(struct gre_h);
801 
802 	/* process GRE flags as packet can be of variable len */
803 	flags = ntohs(gh->flags);
804 
805 	/* Checksum & Offset are present */
806 	if ((flags & GRE_CP) | (flags & GRE_RP))
807 		hlen += 4;
808 	/* We don't support routing fields (variable length) */
809 	if (flags & GRE_RP) {
810 		sc->sc_if.if_ierrors++;
811 		return 0;
812 	}
813 	if (flags & GRE_KP)
814 		hlen += 4;
815 	if (flags & GRE_SP)
816 		hlen += 4;
817 
818 	switch (ntohs(gh->ptype)) { /* ethertypes */
819 #ifdef INET
820 	case ETHERTYPE_IP:
821 		pktq = ip_pktq;
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 		pktq = ip6_pktq;
835 		af = AF_INET6;
836 		break;
837 #endif
838 #ifdef MPLS
839 	case ETHERTYPE_MPLS:
840 		ifq = &mplsintrq;
841 		isr = NETISR_MPLS;
842 		af = AF_MPLS;
843 		break;
844 #endif
845 	default:	   /* others not yet supported */
846 		GRE_DPRINTF(sc, "unhandled ethertype 0x%04x\n",
847 		    ntohs(gh->ptype));
848 		sc->sc_if.if_noproto++;
849 		return 0;
850 	}
851 
852 	if (hlen > m->m_pkthdr.len) {
853 		m_freem(m);
854 		sc->sc_if.if_ierrors++;
855 		return 1;
856 	}
857 	m_adj(m, hlen);
858 
859 	bpf_mtap_af(&sc->sc_if, af, m, BPF_D_IN);
860 
861 	m_set_rcvif(m, &sc->sc_if);
862 
863 	if (__predict_true(pktq)) {
864 		if (__predict_false(!pktq_enqueue(pktq, m, 0))) {
865 			m_freem(m);
866 		}
867 		return 1;
868 	}
869 
870 	s = splnet();
871 	if (IF_QFULL(ifq)) {
872 		IF_DROP(ifq);
873 		m_freem(m);
874 	} else {
875 		IF_ENQUEUE(ifq, m);
876 	}
877 	/* we need schednetisr since the address family may change */
878 	schednetisr(isr);
879 	splx(s);
880 
881 	return 1;	/* packet is done, no further processing needed */
882 }
883 
884 /*
885  * The output routine. Takes a packet and encapsulates it in the protocol
886  * given by sc->sc_soparm.sp_proto. See also RFC 1701 and RFC 2004
887  */
888 static int
889 gre_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
890     const struct rtentry *rt)
891 {
892 	int error = 0;
893 	struct gre_softc *sc = ifp->if_softc;
894 	struct gre_h *gh;
895 	uint16_t etype = 0;
896 
897 	KASSERT((m->m_flags & M_PKTHDR) != 0);
898 
899 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) {
900 		m_freem(m);
901 		error = ENETDOWN;
902 		goto end;
903 	}
904 
905 	bpf_mtap_af(ifp, dst->sa_family, m, BPF_D_OUT);
906 
907 	m->m_flags &= ~(M_BCAST|M_MCAST);
908 
909 	GRE_DPRINTF(sc, "dst->sa_family=%d\n", dst->sa_family);
910 	switch (dst->sa_family) {
911 #ifdef INET
912 	case AF_INET:
913 		/*
914 		 * TBD Extract the IP ToS field and set the
915 		 * encapsulating protocol's ToS to suit.
916 		 */
917 		etype = htons(ETHERTYPE_IP);
918 		break;
919 #endif
920 #ifdef NETATALK
921 	case AF_APPLETALK:
922 		etype = htons(ETHERTYPE_ATALK);
923 		break;
924 #endif
925 #ifdef INET6
926 	case AF_INET6:
927 		etype = htons(ETHERTYPE_IPV6);
928 		break;
929 #endif
930 	default:
931 		IF_DROP(&ifp->if_snd);
932 		m_freem(m);
933 		error = EAFNOSUPPORT;
934 		goto end;
935 	}
936 
937 #ifdef MPLS
938 	if (rt != NULL && rt_gettag(rt) != NULL) {
939 		union mpls_shim msh;
940 		msh.s_addr = MPLS_GETSADDR(rt);
941 		if (msh.shim.label != MPLS_LABEL_IMPLNULL)
942 			etype = htons(ETHERTYPE_MPLS);
943 	}
944 #endif
945 
946 	M_PREPEND(m, sizeof(*gh), M_DONTWAIT);
947 
948 	if (m == NULL) {
949 		IF_DROP(&ifp->if_snd);
950 		error = ENOBUFS;
951 		goto end;
952 	}
953 
954 	gh = mtod(m, struct gre_h *);
955 	gh->flags = 0;
956 	gh->ptype = etype;
957 	/* XXX Need to handle IP ToS.  Look at how I handle IP TTL. */
958 
959 	ifp->if_opackets++;
960 	ifp->if_obytes += m->m_pkthdr.len;
961 
962 	/* Clear checksum-offload flags. */
963 	m->m_pkthdr.csum_flags = 0;
964 	m->m_pkthdr.csum_data = 0;
965 
966 	/* send it off */
967 	if ((error = gre_bufq_enqueue(&sc->sc_snd, m)) != 0) {
968 		sc->sc_oflow_ev.ev_count++;
969 		m_freem(m);
970 	} else
971 		softint_schedule(sc->sc_si);
972 
973 end:
974 	if (error)
975 		ifp->if_oerrors++;
976 	return error;
977 }
978 
979 static int
980 gre_getsockname(struct socket *so, struct sockaddr *nam)
981 {
982 	return (*so->so_proto->pr_usrreqs->pr_sockaddr)(so, nam);
983 }
984 
985 static int
986 gre_getpeername(struct socket *so, struct sockaddr *nam)
987 {
988 	return (*so->so_proto->pr_usrreqs->pr_peeraddr)(so, nam);
989 }
990 
991 static int
992 gre_getnames(struct socket *so, struct lwp *l, struct sockaddr_storage *src,
993     struct sockaddr_storage *dst)
994 {
995 	struct sockaddr_storage ss;
996 	int rc;
997 
998 	solock(so);
999 	if ((rc = gre_getsockname(so, (struct sockaddr *)&ss)) != 0)
1000 		goto out;
1001 	*src = ss;
1002 
1003 	if ((rc = gre_getpeername(so, (struct sockaddr *)&ss)) != 0)
1004 		goto out;
1005 	*dst = ss;
1006 out:
1007 	sounlock(so);
1008 	return rc;
1009 }
1010 
1011 static void
1012 gre_fp_recvloop(void *arg)
1013 {
1014 	struct gre_softc *sc = arg;
1015 
1016 	mutex_enter(&sc->sc_mtx);
1017 	while (gre_fp_recv(sc))
1018 		;
1019 	mutex_exit(&sc->sc_mtx);
1020 	kthread_exit(0);
1021 }
1022 
1023 static bool
1024 gre_fp_recv(struct gre_softc *sc)
1025 {
1026 	int fd, ofd, rc;
1027 	file_t *fp;
1028 
1029 	fp = sc->sc_fp;
1030 	ofd = sc->sc_fd;
1031 	fd = -1;
1032 
1033 	switch (sc->sc_msg) {
1034 	case GRE_M_STOP:
1035 		cv_signal(&sc->sc_fp_condvar);
1036 		return false;
1037 	case GRE_M_SETFP:
1038 		mutex_exit(&sc->sc_mtx);
1039 		rc = fd_dup(fp, 0, &fd, 0);
1040 		mutex_enter(&sc->sc_mtx);
1041 		if (rc != 0) {
1042 			sc->sc_msg = GRE_M_ERR;
1043 			break;
1044 		}
1045 		/*FALLTHROUGH*/
1046 	case GRE_M_DELFP:
1047 		mutex_exit(&sc->sc_mtx);
1048 		if (ofd != -1 && fd_getfile(ofd) != NULL)
1049 			fd_close(ofd);
1050 		mutex_enter(&sc->sc_mtx);
1051 		sc->sc_fd = fd;
1052 		sc->sc_msg = GRE_M_OK;
1053 		break;
1054 	default:
1055 		gre_fp_wait(sc);
1056 		return true;
1057 	}
1058 	cv_signal(&sc->sc_fp_condvar);
1059 	return true;
1060 }
1061 
1062 static bool
1063 gre_fp_send(struct gre_softc *sc, enum gre_msg msg, file_t *fp)
1064 {
1065 	bool rc;
1066 
1067 	mutex_enter(&sc->sc_mtx);
1068 	while (sc->sc_msg != GRE_M_NONE)
1069 		gre_fp_wait(sc);
1070 	sc->sc_fp = fp;
1071 	sc->sc_msg = msg;
1072 	cv_signal(&sc->sc_fp_condvar);
1073 	while (sc->sc_msg != GRE_M_STOP && sc->sc_msg != GRE_M_OK &&
1074 	            sc->sc_msg != GRE_M_ERR)
1075 		gre_fp_wait(sc);
1076 	rc = (sc->sc_msg != GRE_M_ERR);
1077 	sc->sc_msg = GRE_M_NONE;
1078 	cv_signal(&sc->sc_fp_condvar);
1079 	mutex_exit(&sc->sc_mtx);
1080 	return rc;
1081 }
1082 
1083 static int
1084 gre_ssock(struct ifnet *ifp, struct gre_soparm *sp, int fd)
1085 {
1086 	int error = 0;
1087 	const struct protosw *pr;
1088 	file_t *fp;
1089 	struct gre_softc *sc = ifp->if_softc;
1090 	struct socket *so;
1091 	struct sockaddr_storage dst, src;
1092 
1093 	if ((fp = fd_getfile(fd)) == NULL)
1094 		return EBADF;
1095 	if (fp->f_type != DTYPE_SOCKET) {
1096 		fd_putfile(fd);
1097 		return ENOTSOCK;
1098 	}
1099 
1100 	GRE_DPRINTF(sc, "\n");
1101 
1102 	so = fp->f_socket;
1103 	pr = so->so_proto;
1104 
1105 	GRE_DPRINTF(sc, "type %d, proto %d\n", pr->pr_type, pr->pr_protocol);
1106 
1107 	if ((pr->pr_flags & PR_ATOMIC) == 0 ||
1108 	    (sp->sp_type != 0 && pr->pr_type != sp->sp_type) ||
1109 	    (sp->sp_proto != 0 && pr->pr_protocol != 0 &&
1110 	     pr->pr_protocol != sp->sp_proto)) {
1111 		error = EINVAL;
1112 		goto err;
1113 	}
1114 
1115 	GRE_DPRINTF(sc, "\n");
1116 
1117 	/* check address */
1118 	if ((error = gre_getnames(so, curlwp, &src, &dst)) != 0)
1119 		goto err;
1120 
1121 	GRE_DPRINTF(sc, "\n");
1122 
1123 	if (!gre_fp_send(sc, GRE_M_SETFP, fp)) {
1124 		error = EBUSY;
1125 		goto err;
1126 	}
1127 
1128 	GRE_DPRINTF(sc, "\n");
1129 
1130 	sp->sp_src = src;
1131 	sp->sp_dst = dst;
1132 
1133 	sp->sp_so = so;
1134 
1135 err:
1136 	fd_putfile(fd);
1137 	return error;
1138 }
1139 
1140 static bool
1141 sockaddr_is_anyaddr(const struct sockaddr *sa)
1142 {
1143 	socklen_t anylen, salen;
1144 	const void *anyaddr, *addr;
1145 
1146 	if ((anyaddr = sockaddr_anyaddr(sa, &anylen)) == NULL ||
1147 	    (addr = sockaddr_const_addr(sa, &salen)) == NULL)
1148 		return false;
1149 
1150 	if (salen > anylen)
1151 		return false;
1152 
1153 	return memcmp(anyaddr, addr, MIN(anylen, salen)) == 0;
1154 }
1155 
1156 static bool
1157 gre_is_nullconf(const struct gre_soparm *sp)
1158 {
1159 	return sockaddr_is_anyaddr(sstocsa(&sp->sp_src)) ||
1160 	       sockaddr_is_anyaddr(sstocsa(&sp->sp_dst));
1161 }
1162 
1163 static void
1164 gre_clearconf(struct gre_soparm *sp, bool force)
1165 {
1166 	if (sp->sp_bysock || force) {
1167 		sockaddr_copy(sstosa(&sp->sp_src), sizeof(sp->sp_src),
1168 		    sockaddr_any(sstosa(&sp->sp_src)));
1169 		sockaddr_copy(sstosa(&sp->sp_dst), sizeof(sp->sp_dst),
1170 		    sockaddr_any(sstosa(&sp->sp_dst)));
1171 		sp->sp_bysock = false;
1172 	}
1173 	sp->sp_so = NULL; /* XXX */
1174 }
1175 
1176 static int
1177 gre_ioctl(struct ifnet *ifp, const u_long cmd, void *data)
1178 {
1179 	struct ifreq *ifr;
1180 	struct ifaddr *ifa = (struct ifaddr *)data;
1181 	struct if_laddrreq *lifr = (struct if_laddrreq *)data;
1182 	struct gre_softc *sc = ifp->if_softc;
1183 	struct gre_soparm *sp;
1184 	int fd, error = 0, oproto, otype, s;
1185 	struct gre_soparm sp0;
1186 
1187 	ifr = data;
1188 
1189 	GRE_DPRINTF(sc, "cmd %lu\n", cmd);
1190 
1191 	switch (cmd) {
1192 	case GRESPROTO:
1193 	case GRESADDRD:
1194 	case GRESADDRS:
1195 	case GRESSOCK:
1196 	case GREDSOCK:
1197 		if (kauth_authorize_network(curlwp->l_cred,
1198 		    KAUTH_NETWORK_INTERFACE,
1199 		    KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
1200 		    NULL) != 0)
1201 			return EPERM;
1202 		break;
1203 	default:
1204 		break;
1205 	}
1206 
1207 	s = splnet();
1208 
1209 	sp0 = sc->sc_soparm;
1210 	sp0.sp_so = NULL;
1211 	sp = &sp0;
1212 
1213 	GRE_DPRINTF(sc, "\n");
1214 
1215 	switch (cmd) {
1216 	case SIOCINITIFADDR:
1217 		GRE_DPRINTF(sc, "\n");
1218 		if ((ifp->if_flags & IFF_UP) != 0)
1219 			break;
1220 		gre_clearconf(sp, false);
1221 		ifp->if_flags |= IFF_UP;
1222 		ifa->ifa_rtrequest = p2p_rtrequest;
1223 		goto mksocket;
1224 	case SIOCSIFFLAGS:
1225 		if ((error = ifioctl_common(ifp, cmd, data)) != 0)
1226 			break;
1227 		oproto = sp->sp_proto;
1228 		otype = sp->sp_type;
1229 		switch (ifr->ifr_flags & (IFF_LINK0|IFF_LINK2)) {
1230 		case IFF_LINK0|IFF_LINK2:
1231 			sp->sp_proto = IPPROTO_UDP;
1232 			sp->sp_type = SOCK_DGRAM;
1233 			break;
1234 		case IFF_LINK2:
1235 			sp->sp_proto = 0;
1236 			sp->sp_type = 0;
1237 			break;
1238 		case IFF_LINK0:
1239 			sp->sp_proto = IPPROTO_GRE;
1240 			sp->sp_type = SOCK_RAW;
1241 			break;
1242 		default:
1243 			GRE_DPRINTF(sc, "\n");
1244 			error = EINVAL;
1245 			goto out;
1246 		}
1247 		GRE_DPRINTF(sc, "\n");
1248 		gre_clearconf(sp, false);
1249 		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) ==
1250 		    (IFF_UP|IFF_RUNNING) &&
1251 		    (oproto == sp->sp_proto || sp->sp_proto == 0) &&
1252 		    (otype == sp->sp_type || sp->sp_type == 0))
1253 			break;
1254 		switch (sp->sp_proto) {
1255 		case IPPROTO_UDP:
1256 		case IPPROTO_GRE:
1257 			goto mksocket;
1258 		default:
1259 			break;
1260 		}
1261 		break;
1262 	case SIOCSIFMTU:
1263 		/* XXX determine MTU automatically by probing w/
1264 		 * XXX do-not-fragment packets?
1265 		 */
1266 		if (ifr->ifr_mtu < 576) {
1267 			error = EINVAL;
1268 			break;
1269 		}
1270 		/*FALLTHROUGH*/
1271 	case SIOCGIFMTU:
1272 		if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET)
1273 			error = 0;
1274 		break;
1275 	case SIOCADDMULTI:
1276 	case SIOCDELMULTI:
1277 		if (ifr == NULL) {
1278 			error = EAFNOSUPPORT;
1279 			break;
1280 		}
1281 		switch (ifreq_getaddr(cmd, ifr)->sa_family) {
1282 #ifdef INET
1283 		case AF_INET:
1284 			break;
1285 #endif
1286 #ifdef INET6
1287 		case AF_INET6:
1288 			break;
1289 #endif
1290 		default:
1291 			error = EAFNOSUPPORT;
1292 			break;
1293 		}
1294 		break;
1295 	case GRESPROTO:
1296 		gre_clearconf(sp, false);
1297 		oproto = sp->sp_proto;
1298 		otype = sp->sp_type;
1299 		sp->sp_proto = ifr->ifr_flags;
1300 		switch (sp->sp_proto) {
1301 		case IPPROTO_UDP:
1302 			ifp->if_flags |= IFF_LINK0|IFF_LINK2;
1303 			sp->sp_type = SOCK_DGRAM;
1304 			break;
1305 		case IPPROTO_GRE:
1306 			ifp->if_flags |= IFF_LINK0;
1307 			ifp->if_flags &= ~IFF_LINK2;
1308 			sp->sp_type = SOCK_RAW;
1309 			break;
1310 		case 0:
1311 			ifp->if_flags &= ~IFF_LINK0;
1312 			ifp->if_flags |= IFF_LINK2;
1313 			sp->sp_type = 0;
1314 			break;
1315 		default:
1316 			error = EPROTONOSUPPORT;
1317 			break;
1318 		}
1319 		if ((oproto == sp->sp_proto || sp->sp_proto == 0) &&
1320 		    (otype == sp->sp_type || sp->sp_type == 0))
1321 			break;
1322 		switch (sp->sp_proto) {
1323 		case IPPROTO_UDP:
1324 		case IPPROTO_GRE:
1325 			goto mksocket;
1326 		default:
1327 			break;
1328 		}
1329 		break;
1330 	case GREGPROTO:
1331 		ifr->ifr_flags = sp->sp_proto;
1332 		break;
1333 	case GRESADDRS:
1334 	case GRESADDRD:
1335 		gre_clearconf(sp, false);
1336 		/* set tunnel endpoints and mark interface as up */
1337 		switch (cmd) {
1338 		case GRESADDRS:
1339 			sockaddr_copy(sstosa(&sp->sp_src),
1340 			    sizeof(sp->sp_src), ifreq_getaddr(cmd, ifr));
1341 			break;
1342 		case GRESADDRD:
1343 			sockaddr_copy(sstosa(&sp->sp_dst),
1344 			    sizeof(sp->sp_dst), ifreq_getaddr(cmd, ifr));
1345 			break;
1346 		}
1347 	checkaddr:
1348 		if (sockaddr_any(sstosa(&sp->sp_src)) == NULL ||
1349 		    sockaddr_any(sstosa(&sp->sp_dst)) == NULL) {
1350 			error = EINVAL;
1351 			break;
1352 		}
1353 		/* let gre_socreate() check the rest */
1354 	mksocket:
1355 		GRE_DPRINTF(sc, "\n");
1356 		/* If we're administratively down, or the configuration
1357 		 * is empty, there's no use creating a socket.
1358 		 */
1359 		if ((ifp->if_flags & IFF_UP) == 0 || gre_is_nullconf(sp))
1360 			goto sendconf;
1361 
1362 		GRE_DPRINTF(sc, "\n");
1363 		fd = 0;
1364 		error = gre_socreate(sc, sp, &fd);
1365 		if (error != 0)
1366 			break;
1367 
1368 	setsock:
1369 		GRE_DPRINTF(sc, "\n");
1370 
1371 		error = gre_ssock(ifp, sp, fd);
1372 
1373 		if (cmd != GRESSOCK) {
1374 			GRE_DPRINTF(sc, "\n");
1375 			/* XXX v. dodgy */
1376 			if (fd_getfile(fd) != NULL)
1377 				fd_close(fd);
1378 		}
1379 
1380 		if (error == 0) {
1381 	sendconf:
1382 			GRE_DPRINTF(sc, "\n");
1383 			ifp->if_flags &= ~IFF_RUNNING;
1384 			gre_reconf(sc, sp);
1385 		}
1386 
1387 		break;
1388 	case GREGADDRS:
1389 		ifreq_setaddr(cmd, ifr, sstosa(&sp->sp_src));
1390 		break;
1391 	case GREGADDRD:
1392 		ifreq_setaddr(cmd, ifr, sstosa(&sp->sp_dst));
1393 		break;
1394 	case GREDSOCK:
1395 		GRE_DPRINTF(sc, "\n");
1396 		if (sp->sp_bysock)
1397 			ifp->if_flags &= ~IFF_UP;
1398 		gre_clearconf(sp, false);
1399 		goto mksocket;
1400 	case GRESSOCK:
1401 		GRE_DPRINTF(sc, "\n");
1402 		gre_clearconf(sp, true);
1403 		fd = (int)ifr->ifr_value;
1404 		sp->sp_bysock = true;
1405 		ifp->if_flags |= IFF_UP;
1406 		goto setsock;
1407 	case SIOCSLIFPHYADDR:
1408 		GRE_DPRINTF(sc, "\n");
1409 		if (lifr->addr.ss_family != lifr->dstaddr.ss_family) {
1410 			error = EAFNOSUPPORT;
1411 			break;
1412 		}
1413 		sockaddr_copy(sstosa(&sp->sp_src), sizeof(sp->sp_src),
1414 		    sstosa(&lifr->addr));
1415 		sockaddr_copy(sstosa(&sp->sp_dst), sizeof(sp->sp_dst),
1416 		    sstosa(&lifr->dstaddr));
1417 		GRE_DPRINTF(sc, "\n");
1418 		goto checkaddr;
1419 	case SIOCDIFPHYADDR:
1420 		GRE_DPRINTF(sc, "\n");
1421 		gre_clearconf(sp, true);
1422 		ifp->if_flags &= ~IFF_UP;
1423 		goto mksocket;
1424 	case SIOCGLIFPHYADDR:
1425 		GRE_DPRINTF(sc, "\n");
1426 		if (gre_is_nullconf(sp)) {
1427 			error = EADDRNOTAVAIL;
1428 			break;
1429 		}
1430 		sockaddr_copy(sstosa(&lifr->addr), sizeof(lifr->addr),
1431 		    sstosa(&sp->sp_src));
1432 		sockaddr_copy(sstosa(&lifr->dstaddr), sizeof(lifr->dstaddr),
1433 		    sstosa(&sp->sp_dst));
1434 		GRE_DPRINTF(sc, "\n");
1435 		break;
1436 	default:
1437 		error = ifioctl_common(ifp, cmd, data);
1438 		break;
1439 	}
1440 out:
1441 	GRE_DPRINTF(sc, "\n");
1442 	splx(s);
1443 	return error;
1444 }
1445 
1446 /* ARGSUSED */
1447 void
1448 greattach(int count)
1449 {
1450 
1451 	/*
1452 	 * Nothing to do here, initialization is handled by the
1453 	 * module initialization code in greinit() below.
1454 	 */
1455 }
1456 
1457 static void
1458 greinit(void)
1459 {
1460 	if_clone_attach(&gre_cloner);
1461 }
1462 
1463 static int
1464 gredetach(void)
1465 {
1466 	int error = 0;
1467 
1468 	if (gre_count != 0)
1469 		error = EBUSY;
1470 
1471 	if (error == 0)
1472 		if_clone_detach(&gre_cloner);
1473 
1474 	return error;
1475 }
1476 
1477 /*
1478  * Module infrastructure
1479  */
1480 #include "if_module.h"
1481 
1482 IF_MODULE(MODULE_CLASS_DRIVER, gre, "")
1483