xref: /netbsd-src/sys/net/if_bridge.c (revision e5548b402ae4c44fb816de42c7bba9581ce23ef5)
1 /*	$NetBSD: if_bridge.c,v 1.33 2005/12/11 23:05:24 thorpej Exp $	*/
2 
3 /*
4  * Copyright 2001 Wasabi Systems, Inc.
5  * All rights reserved.
6  *
7  * Written by Jason R. Thorpe for Wasabi Systems, Inc.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed for the NetBSD Project by
20  *	Wasabi Systems, Inc.
21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22  *    or promote products derived from this software without specific prior
23  *    written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 /*
39  * Copyright (c) 1999, 2000 Jason L. Wright (jason@thought.net)
40  * All rights reserved.
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  * 1. Redistributions of source code must retain the above copyright
46  *    notice, this list of conditions and the following disclaimer.
47  * 2. Redistributions in binary form must reproduce the above copyright
48  *    notice, this list of conditions and the following disclaimer in the
49  *    documentation and/or other materials provided with the distribution.
50  * 3. All advertising materials mentioning features or use of this software
51  *    must display the following acknowledgement:
52  *	This product includes software developed by Jason L. Wright
53  * 4. The name of the author may not be used to endorse or promote products
54  *    derived from this software without specific prior written permission.
55  *
56  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
57  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
58  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
59  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
60  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
61  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
62  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
63  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
64  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
65  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
66  * POSSIBILITY OF SUCH DAMAGE.
67  *
68  * OpenBSD: if_bridge.c,v 1.60 2001/06/15 03:38:33 itojun Exp
69  */
70 
71 /*
72  * Network interface bridge support.
73  *
74  * TODO:
75  *
76  *	- Currently only supports Ethernet-like interfaces (Ethernet,
77  *	  802.11, VLANs on Ethernet, etc.)  Figure out a nice way
78  *	  to bridge other types of interfaces (FDDI-FDDI, and maybe
79  *	  consider heterogenous bridges).
80  */
81 
82 #include <sys/cdefs.h>
83 __KERNEL_RCSID(0, "$NetBSD: if_bridge.c,v 1.33 2005/12/11 23:05:24 thorpej Exp $");
84 
85 #include "opt_bridge_ipf.h"
86 #include "opt_inet.h"
87 #include "opt_pfil_hooks.h"
88 #include "bpfilter.h"
89 #include "gif.h"
90 
91 #include <sys/param.h>
92 #include <sys/kernel.h>
93 #include <sys/mbuf.h>
94 #include <sys/queue.h>
95 #include <sys/socket.h>
96 #include <sys/sockio.h>
97 #include <sys/systm.h>
98 #include <sys/proc.h>
99 #include <sys/pool.h>
100 
101 #if NBPFILTER > 0
102 #include <net/bpf.h>
103 #endif
104 #include <net/if.h>
105 #include <net/if_dl.h>
106 #include <net/if_types.h>
107 #include <net/if_llc.h>
108 
109 #include <net/if_ether.h>
110 #include <net/if_bridgevar.h>
111 
112 #if defined(BRIDGE_IPF) && defined(PFIL_HOOKS)
113 /* Used for bridge_ip[6]_checkbasic */
114 #include <netinet/in.h>
115 #include <netinet/in_systm.h>
116 #include <netinet/ip.h>
117 #include <netinet/ip_var.h>
118 
119 #include <netinet/ip6.h>
120 #include <netinet6/in6_var.h>
121 #include <netinet6/ip6_var.h>
122 #endif /* BRIDGE_IPF && PFIL_HOOKS */
123 
124 /*
125  * Size of the route hash table.  Must be a power of two.
126  */
127 #ifndef BRIDGE_RTHASH_SIZE
128 #define	BRIDGE_RTHASH_SIZE		1024
129 #endif
130 
131 #define	BRIDGE_RTHASH_MASK		(BRIDGE_RTHASH_SIZE - 1)
132 
133 /*
134  * Maximum number of addresses to cache.
135  */
136 #ifndef BRIDGE_RTABLE_MAX
137 #define	BRIDGE_RTABLE_MAX		100
138 #endif
139 
140 /*
141  * Spanning tree defaults.
142  */
143 #define	BSTP_DEFAULT_MAX_AGE		(20 * 256)
144 #define	BSTP_DEFAULT_HELLO_TIME		(2 * 256)
145 #define	BSTP_DEFAULT_FORWARD_DELAY	(15 * 256)
146 #define	BSTP_DEFAULT_HOLD_TIME		(1 * 256)
147 #define	BSTP_DEFAULT_BRIDGE_PRIORITY	0x8000
148 #define	BSTP_DEFAULT_PORT_PRIORITY	0x80
149 #define	BSTP_DEFAULT_PATH_COST		55
150 
151 /*
152  * Timeout (in seconds) for entries learned dynamically.
153  */
154 #ifndef BRIDGE_RTABLE_TIMEOUT
155 #define	BRIDGE_RTABLE_TIMEOUT		(20 * 60)	/* same as ARP */
156 #endif
157 
158 /*
159  * Number of seconds between walks of the route list.
160  */
161 #ifndef BRIDGE_RTABLE_PRUNE_PERIOD
162 #define	BRIDGE_RTABLE_PRUNE_PERIOD	(5 * 60)
163 #endif
164 
165 int	bridge_rtable_prune_period = BRIDGE_RTABLE_PRUNE_PERIOD;
166 
167 static struct pool bridge_rtnode_pool;
168 
169 void	bridgeattach(int);
170 
171 static int	bridge_clone_create(struct if_clone *, int);
172 static int	bridge_clone_destroy(struct ifnet *);
173 
174 static int	bridge_ioctl(struct ifnet *, u_long, caddr_t);
175 static int	bridge_init(struct ifnet *);
176 static void	bridge_stop(struct ifnet *, int);
177 static void	bridge_start(struct ifnet *);
178 
179 static void	bridge_forward(struct bridge_softc *, struct mbuf *m);
180 
181 static void	bridge_timer(void *);
182 
183 static void	bridge_broadcast(struct bridge_softc *, struct ifnet *,
184 				 struct mbuf *);
185 
186 static int	bridge_rtupdate(struct bridge_softc *, const uint8_t *,
187 				struct ifnet *, int, uint8_t);
188 static struct ifnet *bridge_rtlookup(struct bridge_softc *, const uint8_t *);
189 static void	bridge_rttrim(struct bridge_softc *);
190 static void	bridge_rtage(struct bridge_softc *);
191 static void	bridge_rtflush(struct bridge_softc *, int);
192 static int	bridge_rtdaddr(struct bridge_softc *, const uint8_t *);
193 static void	bridge_rtdelete(struct bridge_softc *, struct ifnet *ifp);
194 
195 static int	bridge_rtable_init(struct bridge_softc *);
196 static void	bridge_rtable_fini(struct bridge_softc *);
197 
198 static struct bridge_rtnode *bridge_rtnode_lookup(struct bridge_softc *,
199 						  const uint8_t *);
200 static int	bridge_rtnode_insert(struct bridge_softc *,
201 				     struct bridge_rtnode *);
202 static void	bridge_rtnode_destroy(struct bridge_softc *,
203 				      struct bridge_rtnode *);
204 
205 static struct bridge_iflist *bridge_lookup_member(struct bridge_softc *,
206 						  const char *name);
207 static struct bridge_iflist *bridge_lookup_member_if(struct bridge_softc *,
208 						     struct ifnet *ifp);
209 static void	bridge_delete_member(struct bridge_softc *,
210 				     struct bridge_iflist *);
211 
212 static int	bridge_ioctl_add(struct bridge_softc *, void *);
213 static int	bridge_ioctl_del(struct bridge_softc *, void *);
214 static int	bridge_ioctl_gifflags(struct bridge_softc *, void *);
215 static int	bridge_ioctl_sifflags(struct bridge_softc *, void *);
216 static int	bridge_ioctl_scache(struct bridge_softc *, void *);
217 static int	bridge_ioctl_gcache(struct bridge_softc *, void *);
218 static int	bridge_ioctl_gifs(struct bridge_softc *, void *);
219 static int	bridge_ioctl_rts(struct bridge_softc *, void *);
220 static int	bridge_ioctl_saddr(struct bridge_softc *, void *);
221 static int	bridge_ioctl_sto(struct bridge_softc *, void *);
222 static int	bridge_ioctl_gto(struct bridge_softc *, void *);
223 static int	bridge_ioctl_daddr(struct bridge_softc *, void *);
224 static int	bridge_ioctl_flush(struct bridge_softc *, void *);
225 static int	bridge_ioctl_gpri(struct bridge_softc *, void *);
226 static int	bridge_ioctl_spri(struct bridge_softc *, void *);
227 static int	bridge_ioctl_ght(struct bridge_softc *, void *);
228 static int	bridge_ioctl_sht(struct bridge_softc *, void *);
229 static int	bridge_ioctl_gfd(struct bridge_softc *, void *);
230 static int	bridge_ioctl_sfd(struct bridge_softc *, void *);
231 static int	bridge_ioctl_gma(struct bridge_softc *, void *);
232 static int	bridge_ioctl_sma(struct bridge_softc *, void *);
233 static int	bridge_ioctl_sifprio(struct bridge_softc *, void *);
234 static int	bridge_ioctl_sifcost(struct bridge_softc *, void *);
235 #if defined(BRIDGE_IPF) && defined(PFIL_HOOKS)
236 static int	bridge_ioctl_gfilt(struct bridge_softc *, void *);
237 static int	bridge_ioctl_sfilt(struct bridge_softc *, void *);
238 static int	bridge_ipf(void *, struct mbuf **, struct ifnet *, int);
239 static int	bridge_ip_checkbasic(struct mbuf **mp);
240 # ifdef INET6
241 static int	bridge_ip6_checkbasic(struct mbuf **mp);
242 # endif /* INET6 */
243 #endif /* BRIDGE_IPF && PFIL_HOOKS */
244 
245 struct bridge_control {
246 	int	(*bc_func)(struct bridge_softc *, void *);
247 	int	bc_argsize;
248 	int	bc_flags;
249 };
250 
251 #define	BC_F_COPYIN		0x01	/* copy arguments in */
252 #define	BC_F_COPYOUT		0x02	/* copy arguments out */
253 #define	BC_F_SUSER		0x04	/* do super-user check */
254 
255 static const struct bridge_control bridge_control_table[] = {
256 	{ bridge_ioctl_add,		sizeof(struct ifbreq),
257 	  BC_F_COPYIN|BC_F_SUSER },
258 	{ bridge_ioctl_del,		sizeof(struct ifbreq),
259 	  BC_F_COPYIN|BC_F_SUSER },
260 
261 	{ bridge_ioctl_gifflags,	sizeof(struct ifbreq),
262 	  BC_F_COPYIN|BC_F_COPYOUT },
263 	{ bridge_ioctl_sifflags,	sizeof(struct ifbreq),
264 	  BC_F_COPYIN|BC_F_SUSER },
265 
266 	{ bridge_ioctl_scache,		sizeof(struct ifbrparam),
267 	  BC_F_COPYIN|BC_F_SUSER },
268 	{ bridge_ioctl_gcache,		sizeof(struct ifbrparam),
269 	  BC_F_COPYOUT },
270 
271 	{ bridge_ioctl_gifs,		sizeof(struct ifbifconf),
272 	  BC_F_COPYIN|BC_F_COPYOUT },
273 	{ bridge_ioctl_rts,		sizeof(struct ifbaconf),
274 	  BC_F_COPYIN|BC_F_COPYOUT },
275 
276 	{ bridge_ioctl_saddr,		sizeof(struct ifbareq),
277 	  BC_F_COPYIN|BC_F_SUSER },
278 
279 	{ bridge_ioctl_sto,		sizeof(struct ifbrparam),
280 	  BC_F_COPYIN|BC_F_SUSER },
281 	{ bridge_ioctl_gto,		sizeof(struct ifbrparam),
282 	  BC_F_COPYOUT },
283 
284 	{ bridge_ioctl_daddr,		sizeof(struct ifbareq),
285 	  BC_F_COPYIN|BC_F_SUSER },
286 
287 	{ bridge_ioctl_flush,		sizeof(struct ifbreq),
288 	  BC_F_COPYIN|BC_F_SUSER },
289 
290 	{ bridge_ioctl_gpri,		sizeof(struct ifbrparam),
291 	  BC_F_COPYOUT },
292 	{ bridge_ioctl_spri,		sizeof(struct ifbrparam),
293 	  BC_F_COPYIN|BC_F_SUSER },
294 
295 	{ bridge_ioctl_ght,		sizeof(struct ifbrparam),
296 	  BC_F_COPYOUT },
297 	{ bridge_ioctl_sht,		sizeof(struct ifbrparam),
298 	  BC_F_COPYIN|BC_F_SUSER },
299 
300 	{ bridge_ioctl_gfd,		sizeof(struct ifbrparam),
301 	  BC_F_COPYOUT },
302 	{ bridge_ioctl_sfd,		sizeof(struct ifbrparam),
303 	  BC_F_COPYIN|BC_F_SUSER },
304 
305 	{ bridge_ioctl_gma,		sizeof(struct ifbrparam),
306 	  BC_F_COPYOUT },
307 	{ bridge_ioctl_sma,		sizeof(struct ifbrparam),
308 	  BC_F_COPYIN|BC_F_SUSER },
309 
310 	{ bridge_ioctl_sifprio,		sizeof(struct ifbreq),
311 	  BC_F_COPYIN|BC_F_SUSER },
312 
313 	{ bridge_ioctl_sifcost,		sizeof(struct ifbreq),
314 	  BC_F_COPYIN|BC_F_SUSER },
315 #if defined(BRIDGE_IPF) && defined(PFIL_HOOKS)
316 	{ bridge_ioctl_gfilt,		sizeof(struct ifbrparam),
317 	  BC_F_COPYOUT },
318 	{ bridge_ioctl_sfilt,		sizeof(struct ifbrparam),
319 	  BC_F_COPYIN|BC_F_SUSER },
320 #endif /* BRIDGE_IPF && PFIL_HOOKS */
321 };
322 static const int bridge_control_table_size =
323     sizeof(bridge_control_table) / sizeof(bridge_control_table[0]);
324 
325 static LIST_HEAD(, bridge_softc) bridge_list;
326 
327 static struct if_clone bridge_cloner =
328     IF_CLONE_INITIALIZER("bridge", bridge_clone_create, bridge_clone_destroy);
329 
330 /*
331  * bridgeattach:
332  *
333  *	Pseudo-device attach routine.
334  */
335 void
336 bridgeattach(int n)
337 {
338 
339 	pool_init(&bridge_rtnode_pool, sizeof(struct bridge_rtnode),
340 	    0, 0, 0, "brtpl", NULL);
341 
342 	LIST_INIT(&bridge_list);
343 	if_clone_attach(&bridge_cloner);
344 }
345 
346 /*
347  * bridge_clone_create:
348  *
349  *	Create a new bridge instance.
350  */
351 static int
352 bridge_clone_create(struct if_clone *ifc, int unit)
353 {
354 	struct bridge_softc *sc;
355 	struct ifnet *ifp;
356 	int s;
357 
358 	sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK);
359 	memset(sc, 0, sizeof(*sc));
360 	ifp = &sc->sc_if;
361 
362 	sc->sc_brtmax = BRIDGE_RTABLE_MAX;
363 	sc->sc_brttimeout = BRIDGE_RTABLE_TIMEOUT;
364 	sc->sc_bridge_max_age = BSTP_DEFAULT_MAX_AGE;
365 	sc->sc_bridge_hello_time = BSTP_DEFAULT_HELLO_TIME;
366 	sc->sc_bridge_forward_delay = BSTP_DEFAULT_FORWARD_DELAY;
367 	sc->sc_bridge_priority = BSTP_DEFAULT_BRIDGE_PRIORITY;
368 	sc->sc_hold_time = BSTP_DEFAULT_HOLD_TIME;
369 	sc->sc_filter_flags = 0;
370 
371 	/* Initialize our routing table. */
372 	bridge_rtable_init(sc);
373 
374 	callout_init(&sc->sc_brcallout);
375 	callout_init(&sc->sc_bstpcallout);
376 
377 	LIST_INIT(&sc->sc_iflist);
378 
379 	snprintf(ifp->if_xname, sizeof(ifp->if_xname), "%s%d", ifc->ifc_name,
380 	    unit);
381 	ifp->if_softc = sc;
382 	ifp->if_mtu = ETHERMTU;
383 	ifp->if_ioctl = bridge_ioctl;
384 	ifp->if_output = bridge_output;
385 	ifp->if_start = bridge_start;
386 	ifp->if_stop = bridge_stop;
387 	ifp->if_init = bridge_init;
388 	ifp->if_type = IFT_BRIDGE;
389 	ifp->if_addrlen = 0;
390 	ifp->if_dlt = DLT_EN10MB;
391 	ifp->if_hdrlen = ETHER_HDR_LEN;
392 
393 	if_attach(ifp);
394 
395 	if_alloc_sadl(ifp);
396 
397 	s = splnet();
398 	LIST_INSERT_HEAD(&bridge_list, sc, sc_list);
399 	splx(s);
400 
401 	return (0);
402 }
403 
404 /*
405  * bridge_clone_destroy:
406  *
407  *	Destroy a bridge instance.
408  */
409 static int
410 bridge_clone_destroy(struct ifnet *ifp)
411 {
412 	struct bridge_softc *sc = ifp->if_softc;
413 	struct bridge_iflist *bif;
414 	int s;
415 
416 	s = splnet();
417 
418 	bridge_stop(ifp, 1);
419 
420 	while ((bif = LIST_FIRST(&sc->sc_iflist)) != NULL)
421 		bridge_delete_member(sc, bif);
422 
423 	LIST_REMOVE(sc, sc_list);
424 
425 	splx(s);
426 
427 	if_detach(ifp);
428 
429 	/* Tear down the routing table. */
430 	bridge_rtable_fini(sc);
431 
432 	free(sc, M_DEVBUF);
433 
434 	return (0);
435 }
436 
437 /*
438  * bridge_ioctl:
439  *
440  *	Handle a control request from the operator.
441  */
442 static int
443 bridge_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
444 {
445 	struct bridge_softc *sc = ifp->if_softc;
446 	struct proc *p = curproc;	/* XXX */
447 	union {
448 		struct ifbreq ifbreq;
449 		struct ifbifconf ifbifconf;
450 		struct ifbareq ifbareq;
451 		struct ifbaconf ifbaconf;
452 		struct ifbrparam ifbrparam;
453 	} args;
454 	struct ifdrv *ifd = (struct ifdrv *) data;
455 	const struct bridge_control *bc;
456 	int s, error = 0;
457 
458 	s = splnet();
459 
460 	switch (cmd) {
461 	case SIOCGDRVSPEC:
462 	case SIOCSDRVSPEC:
463 		if (ifd->ifd_cmd >= bridge_control_table_size) {
464 			error = EINVAL;
465 			break;
466 		}
467 		bc = &bridge_control_table[ifd->ifd_cmd];
468 
469 		if (cmd == SIOCGDRVSPEC &&
470 		    (bc->bc_flags & BC_F_COPYOUT) == 0) {
471 			error = EINVAL;
472 			break;
473 		}
474 		else if (cmd == SIOCSDRVSPEC &&
475 		    (bc->bc_flags & BC_F_COPYOUT) != 0) {
476 			error = EINVAL;
477 			break;
478 		}
479 
480 		if (bc->bc_flags & BC_F_SUSER) {
481 			error = suser(p->p_ucred, &p->p_acflag);
482 			if (error)
483 				break;
484 		}
485 
486 		if (ifd->ifd_len != bc->bc_argsize ||
487 		    ifd->ifd_len > sizeof(args)) {
488 			error = EINVAL;
489 			break;
490 		}
491 
492 		if (bc->bc_flags & BC_F_COPYIN) {
493 			error = copyin(ifd->ifd_data, &args, ifd->ifd_len);
494 			if (error)
495 				break;
496 		}
497 
498 		error = (*bc->bc_func)(sc, &args);
499 		if (error)
500 			break;
501 
502 		if (bc->bc_flags & BC_F_COPYOUT)
503 			error = copyout(&args, ifd->ifd_data, ifd->ifd_len);
504 
505 		break;
506 
507 	case SIOCSIFFLAGS:
508 		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) == IFF_RUNNING) {
509 			/*
510 			 * If interface is marked down and it is running,
511 			 * then stop and disable it.
512 			 */
513 			(*ifp->if_stop)(ifp, 1);
514 		} else if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) == IFF_UP) {
515 			/*
516 			 * If interface is marked up and it is stopped, then
517 			 * start it.
518 			 */
519 			error = (*ifp->if_init)(ifp);
520 		}
521 		break;
522 
523 	default:
524 		error = ENOTTY;
525 		break;
526 	}
527 
528 	splx(s);
529 
530 	return (error);
531 }
532 
533 /*
534  * bridge_lookup_member:
535  *
536  *	Lookup a bridge member interface.  Must be called at splnet().
537  */
538 static struct bridge_iflist *
539 bridge_lookup_member(struct bridge_softc *sc, const char *name)
540 {
541 	struct bridge_iflist *bif;
542 	struct ifnet *ifp;
543 
544 	LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
545 		ifp = bif->bif_ifp;
546 		if (strcmp(ifp->if_xname, name) == 0)
547 			return (bif);
548 	}
549 
550 	return (NULL);
551 }
552 
553 /*
554  * bridge_lookup_member_if:
555  *
556  *	Lookup a bridge member interface by ifnet*.  Must be called at splnet().
557  */
558 static struct bridge_iflist *
559 bridge_lookup_member_if(struct bridge_softc *sc, struct ifnet *member_ifp)
560 {
561 	struct bridge_iflist *bif;
562 
563 	LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
564 		if (bif->bif_ifp == member_ifp)
565 			return (bif);
566 	}
567 
568 	return (NULL);
569 }
570 
571 /*
572  * bridge_delete_member:
573  *
574  *	Delete the specified member interface.
575  */
576 static void
577 bridge_delete_member(struct bridge_softc *sc, struct bridge_iflist *bif)
578 {
579 	struct ifnet *ifs = bif->bif_ifp;
580 
581 	switch (ifs->if_type) {
582 	case IFT_ETHER:
583 		/*
584 		 * Take the interface out of promiscuous mode.
585 		 */
586 		(void) ifpromisc(ifs, 0);
587 		break;
588 #if NGIF > 0
589 	case IFT_GIF:
590 		break;
591 #endif
592 	default:
593 #ifdef DIAGNOSTIC
594 		panic("bridge_delete_member: impossible");
595 #endif
596 		break;
597 	}
598 
599 	ifs->if_bridge = NULL;
600 	LIST_REMOVE(bif, bif_next);
601 
602 	bridge_rtdelete(sc, ifs);
603 
604 	free(bif, M_DEVBUF);
605 
606 	if (sc->sc_if.if_flags & IFF_RUNNING)
607 		bstp_initialization(sc);
608 }
609 
610 static int
611 bridge_ioctl_add(struct bridge_softc *sc, void *arg)
612 {
613 	struct ifbreq *req = arg;
614 	struct bridge_iflist *bif = NULL;
615 	struct ifnet *ifs;
616 	int error = 0;
617 
618 	ifs = ifunit(req->ifbr_ifsname);
619 	if (ifs == NULL)
620 		return (ENOENT);
621 
622 	if (sc->sc_if.if_mtu != ifs->if_mtu)
623 		return (EINVAL);
624 
625 	if (ifs->if_bridge == sc)
626 		return (EEXIST);
627 
628 	if (ifs->if_bridge != NULL)
629 		return (EBUSY);
630 
631 	bif = malloc(sizeof(*bif), M_DEVBUF, M_NOWAIT);
632 	if (bif == NULL)
633 		return (ENOMEM);
634 
635 	switch (ifs->if_type) {
636 	case IFT_ETHER:
637 		/*
638 		 * Place the interface into promiscuous mode.
639 		 */
640 		error = ifpromisc(ifs, 1);
641 		if (error)
642 			goto out;
643 		break;
644 #if NGIF > 0
645 	case IFT_GIF:
646 		break;
647 #endif
648 	default:
649 		error = EINVAL;
650 		goto out;
651 	}
652 
653 	bif->bif_ifp = ifs;
654 	bif->bif_flags = IFBIF_LEARNING | IFBIF_DISCOVER;
655 	bif->bif_priority = BSTP_DEFAULT_PORT_PRIORITY;
656 	bif->bif_path_cost = BSTP_DEFAULT_PATH_COST;
657 
658 	ifs->if_bridge = sc;
659 	LIST_INSERT_HEAD(&sc->sc_iflist, bif, bif_next);
660 
661 	if (sc->sc_if.if_flags & IFF_RUNNING)
662 		bstp_initialization(sc);
663 	else
664 		bstp_stop(sc);
665 
666  out:
667 	if (error) {
668 		if (bif != NULL)
669 			free(bif, M_DEVBUF);
670 	}
671 	return (error);
672 }
673 
674 static int
675 bridge_ioctl_del(struct bridge_softc *sc, void *arg)
676 {
677 	struct ifbreq *req = arg;
678 	struct bridge_iflist *bif;
679 
680 	bif = bridge_lookup_member(sc, req->ifbr_ifsname);
681 	if (bif == NULL)
682 		return (ENOENT);
683 
684 	bridge_delete_member(sc, bif);
685 
686 	return (0);
687 }
688 
689 static int
690 bridge_ioctl_gifflags(struct bridge_softc *sc, void *arg)
691 {
692 	struct ifbreq *req = arg;
693 	struct bridge_iflist *bif;
694 
695 	bif = bridge_lookup_member(sc, req->ifbr_ifsname);
696 	if (bif == NULL)
697 		return (ENOENT);
698 
699 	req->ifbr_ifsflags = bif->bif_flags;
700 	req->ifbr_state = bif->bif_state;
701 	req->ifbr_priority = bif->bif_priority;
702 	req->ifbr_path_cost = bif->bif_path_cost;
703 	req->ifbr_portno = bif->bif_ifp->if_index & 0xff;
704 
705 	return (0);
706 }
707 
708 static int
709 bridge_ioctl_sifflags(struct bridge_softc *sc, void *arg)
710 {
711 	struct ifbreq *req = arg;
712 	struct bridge_iflist *bif;
713 
714 	bif = bridge_lookup_member(sc, req->ifbr_ifsname);
715 	if (bif == NULL)
716 		return (ENOENT);
717 
718 	if (req->ifbr_ifsflags & IFBIF_STP) {
719 		switch (bif->bif_ifp->if_type) {
720 		case IFT_ETHER:
721 			/* These can do spanning tree. */
722 			break;
723 
724 		default:
725 			/* Nothing else can. */
726 			return (EINVAL);
727 		}
728 	}
729 
730 	bif->bif_flags = req->ifbr_ifsflags;
731 
732 	if (sc->sc_if.if_flags & IFF_RUNNING)
733 		bstp_initialization(sc);
734 
735 	return (0);
736 }
737 
738 static int
739 bridge_ioctl_scache(struct bridge_softc *sc, void *arg)
740 {
741 	struct ifbrparam *param = arg;
742 
743 	sc->sc_brtmax = param->ifbrp_csize;
744 	bridge_rttrim(sc);
745 
746 	return (0);
747 }
748 
749 static int
750 bridge_ioctl_gcache(struct bridge_softc *sc, void *arg)
751 {
752 	struct ifbrparam *param = arg;
753 
754 	param->ifbrp_csize = sc->sc_brtmax;
755 
756 	return (0);
757 }
758 
759 static int
760 bridge_ioctl_gifs(struct bridge_softc *sc, void *arg)
761 {
762 	struct ifbifconf *bifc = arg;
763 	struct bridge_iflist *bif;
764 	struct ifbreq breq;
765 	int count, len, error = 0;
766 
767 	count = 0;
768 	LIST_FOREACH(bif, &sc->sc_iflist, bif_next)
769 		count++;
770 
771 	if (bifc->ifbic_len == 0) {
772 		bifc->ifbic_len = sizeof(breq) * count;
773 		return (0);
774 	}
775 
776 	count = 0;
777 	len = bifc->ifbic_len;
778 	LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
779 		if (len < sizeof(breq))
780 			break;
781 
782 		strlcpy(breq.ifbr_ifsname, bif->bif_ifp->if_xname,
783 		    sizeof(breq.ifbr_ifsname));
784 		breq.ifbr_ifsflags = bif->bif_flags;
785 		breq.ifbr_state = bif->bif_state;
786 		breq.ifbr_priority = bif->bif_priority;
787 		breq.ifbr_path_cost = bif->bif_path_cost;
788 		breq.ifbr_portno = bif->bif_ifp->if_index & 0xff;
789 		error = copyout(&breq, bifc->ifbic_req + count, sizeof(breq));
790 		if (error)
791 			break;
792 		count++;
793 		len -= sizeof(breq);
794 	}
795 
796 	bifc->ifbic_len = sizeof(breq) * count;
797 	return (error);
798 }
799 
800 static int
801 bridge_ioctl_rts(struct bridge_softc *sc, void *arg)
802 {
803 	struct ifbaconf *bac = arg;
804 	struct bridge_rtnode *brt;
805 	struct ifbareq bareq;
806 	int count = 0, error = 0, len;
807 
808 	if (bac->ifbac_len == 0)
809 		return (0);
810 
811 	len = bac->ifbac_len;
812 	LIST_FOREACH(brt, &sc->sc_rtlist, brt_list) {
813 		if (len < sizeof(bareq))
814 			goto out;
815 		strlcpy(bareq.ifba_ifsname, brt->brt_ifp->if_xname,
816 		    sizeof(bareq.ifba_ifsname));
817 		memcpy(bareq.ifba_dst, brt->brt_addr, sizeof(brt->brt_addr));
818 		if ((brt->brt_flags & IFBAF_TYPEMASK) == IFBAF_DYNAMIC)
819 			bareq.ifba_expire = brt->brt_expire - mono_time.tv_sec;
820 		else
821 			bareq.ifba_expire = 0;
822 		bareq.ifba_flags = brt->brt_flags;
823 
824 		error = copyout(&bareq, bac->ifbac_req + count, sizeof(bareq));
825 		if (error)
826 			goto out;
827 		count++;
828 		len -= sizeof(bareq);
829 	}
830  out:
831 	bac->ifbac_len = sizeof(bareq) * count;
832 	return (error);
833 }
834 
835 static int
836 bridge_ioctl_saddr(struct bridge_softc *sc, void *arg)
837 {
838 	struct ifbareq *req = arg;
839 	struct bridge_iflist *bif;
840 	int error;
841 
842 	bif = bridge_lookup_member(sc, req->ifba_ifsname);
843 	if (bif == NULL)
844 		return (ENOENT);
845 
846 	error = bridge_rtupdate(sc, req->ifba_dst, bif->bif_ifp, 1,
847 	    req->ifba_flags);
848 
849 	return (error);
850 }
851 
852 static int
853 bridge_ioctl_sto(struct bridge_softc *sc, void *arg)
854 {
855 	struct ifbrparam *param = arg;
856 
857 	sc->sc_brttimeout = param->ifbrp_ctime;
858 
859 	return (0);
860 }
861 
862 static int
863 bridge_ioctl_gto(struct bridge_softc *sc, void *arg)
864 {
865 	struct ifbrparam *param = arg;
866 
867 	param->ifbrp_ctime = sc->sc_brttimeout;
868 
869 	return (0);
870 }
871 
872 static int
873 bridge_ioctl_daddr(struct bridge_softc *sc, void *arg)
874 {
875 	struct ifbareq *req = arg;
876 
877 	return (bridge_rtdaddr(sc, req->ifba_dst));
878 }
879 
880 static int
881 bridge_ioctl_flush(struct bridge_softc *sc, void *arg)
882 {
883 	struct ifbreq *req = arg;
884 
885 	bridge_rtflush(sc, req->ifbr_ifsflags);
886 
887 	return (0);
888 }
889 
890 static int
891 bridge_ioctl_gpri(struct bridge_softc *sc, void *arg)
892 {
893 	struct ifbrparam *param = arg;
894 
895 	param->ifbrp_prio = sc->sc_bridge_priority;
896 
897 	return (0);
898 }
899 
900 static int
901 bridge_ioctl_spri(struct bridge_softc *sc, void *arg)
902 {
903 	struct ifbrparam *param = arg;
904 
905 	sc->sc_bridge_priority = param->ifbrp_prio;
906 
907 	if (sc->sc_if.if_flags & IFF_RUNNING)
908 		bstp_initialization(sc);
909 
910 	return (0);
911 }
912 
913 static int
914 bridge_ioctl_ght(struct bridge_softc *sc, void *arg)
915 {
916 	struct ifbrparam *param = arg;
917 
918 	param->ifbrp_hellotime = sc->sc_bridge_hello_time >> 8;
919 
920 	return (0);
921 }
922 
923 static int
924 bridge_ioctl_sht(struct bridge_softc *sc, void *arg)
925 {
926 	struct ifbrparam *param = arg;
927 
928 	if (param->ifbrp_hellotime == 0)
929 		return (EINVAL);
930 	sc->sc_bridge_hello_time = param->ifbrp_hellotime << 8;
931 
932 	if (sc->sc_if.if_flags & IFF_RUNNING)
933 		bstp_initialization(sc);
934 
935 	return (0);
936 }
937 
938 static int
939 bridge_ioctl_gfd(struct bridge_softc *sc, void *arg)
940 {
941 	struct ifbrparam *param = arg;
942 
943 	param->ifbrp_fwddelay = sc->sc_bridge_forward_delay >> 8;
944 
945 	return (0);
946 }
947 
948 static int
949 bridge_ioctl_sfd(struct bridge_softc *sc, void *arg)
950 {
951 	struct ifbrparam *param = arg;
952 
953 	if (param->ifbrp_fwddelay == 0)
954 		return (EINVAL);
955 	sc->sc_bridge_forward_delay = param->ifbrp_fwddelay << 8;
956 
957 	if (sc->sc_if.if_flags & IFF_RUNNING)
958 		bstp_initialization(sc);
959 
960 	return (0);
961 }
962 
963 static int
964 bridge_ioctl_gma(struct bridge_softc *sc, void *arg)
965 {
966 	struct ifbrparam *param = arg;
967 
968 	param->ifbrp_maxage = sc->sc_bridge_max_age >> 8;
969 
970 	return (0);
971 }
972 
973 static int
974 bridge_ioctl_sma(struct bridge_softc *sc, void *arg)
975 {
976 	struct ifbrparam *param = arg;
977 
978 	if (param->ifbrp_maxage == 0)
979 		return (EINVAL);
980 	sc->sc_bridge_max_age = param->ifbrp_maxage << 8;
981 
982 	if (sc->sc_if.if_flags & IFF_RUNNING)
983 		bstp_initialization(sc);
984 
985 	return (0);
986 }
987 
988 static int
989 bridge_ioctl_sifprio(struct bridge_softc *sc, void *arg)
990 {
991 	struct ifbreq *req = arg;
992 	struct bridge_iflist *bif;
993 
994 	bif = bridge_lookup_member(sc, req->ifbr_ifsname);
995 	if (bif == NULL)
996 		return (ENOENT);
997 
998 	bif->bif_priority = req->ifbr_priority;
999 
1000 	if (sc->sc_if.if_flags & IFF_RUNNING)
1001 		bstp_initialization(sc);
1002 
1003 	return (0);
1004 }
1005 
1006 #if defined(BRIDGE_IPF) && defined(PFIL_HOOKS)
1007 static int
1008 bridge_ioctl_gfilt(struct bridge_softc *sc, void *arg)
1009 {
1010 	struct ifbrparam *param = arg;
1011 
1012 	param->ifbrp_filter = sc->sc_filter_flags;
1013 
1014 	return (0);
1015 }
1016 
1017 static int
1018 bridge_ioctl_sfilt(struct bridge_softc *sc, void *arg)
1019 {
1020 	struct ifbrparam *param = arg;
1021 	uint32_t nflags, oflags;
1022 
1023 	if (param->ifbrp_filter & ~IFBF_FILT_MASK)
1024 		return (EINVAL);
1025 
1026 	nflags = param->ifbrp_filter;
1027 	oflags = sc->sc_filter_flags;
1028 
1029 	if ((nflags & IFBF_FILT_USEIPF) && !(oflags & IFBF_FILT_USEIPF)) {
1030 		pfil_add_hook((void *)bridge_ipf, NULL, PFIL_IN|PFIL_OUT,
1031 			&sc->sc_if.if_pfil);
1032 	}
1033 	if (!(nflags & IFBF_FILT_USEIPF) && (oflags & IFBF_FILT_USEIPF)) {
1034 		pfil_remove_hook((void *)bridge_ipf, NULL, PFIL_IN|PFIL_OUT,
1035 			&sc->sc_if.if_pfil);
1036 	}
1037 
1038 	sc->sc_filter_flags = nflags;
1039 
1040 	return (0);
1041 }
1042 #endif /* BRIDGE_IPF && PFIL_HOOKS */
1043 
1044 static int
1045 bridge_ioctl_sifcost(struct bridge_softc *sc, void *arg)
1046 {
1047 	struct ifbreq *req = arg;
1048 	struct bridge_iflist *bif;
1049 
1050 	bif = bridge_lookup_member(sc, req->ifbr_ifsname);
1051 	if (bif == NULL)
1052 		return (ENOENT);
1053 
1054 	bif->bif_path_cost = req->ifbr_path_cost;
1055 
1056 	if (sc->sc_if.if_flags & IFF_RUNNING)
1057 		bstp_initialization(sc);
1058 
1059 	return (0);
1060 }
1061 
1062 /*
1063  * bridge_ifdetach:
1064  *
1065  *	Detach an interface from a bridge.  Called when a member
1066  *	interface is detaching.
1067  */
1068 void
1069 bridge_ifdetach(struct ifnet *ifp)
1070 {
1071 	struct bridge_softc *sc = ifp->if_bridge;
1072 	struct ifbreq breq;
1073 
1074 	memset(&breq, 0, sizeof(breq));
1075 	snprintf(breq.ifbr_ifsname, sizeof(breq.ifbr_ifsname), ifp->if_xname);
1076 
1077 	(void) bridge_ioctl_del(sc, &breq);
1078 }
1079 
1080 /*
1081  * bridge_init:
1082  *
1083  *	Initialize a bridge interface.
1084  */
1085 static int
1086 bridge_init(struct ifnet *ifp)
1087 {
1088 	struct bridge_softc *sc = ifp->if_softc;
1089 
1090 	if (ifp->if_flags & IFF_RUNNING)
1091 		return (0);
1092 
1093 	callout_reset(&sc->sc_brcallout, bridge_rtable_prune_period * hz,
1094 	    bridge_timer, sc);
1095 
1096 	ifp->if_flags |= IFF_RUNNING;
1097 	bstp_initialization(sc);
1098 	return (0);
1099 }
1100 
1101 /*
1102  * bridge_stop:
1103  *
1104  *	Stop the bridge interface.
1105  */
1106 static void
1107 bridge_stop(struct ifnet *ifp, int disable)
1108 {
1109 	struct bridge_softc *sc = ifp->if_softc;
1110 
1111 	if ((ifp->if_flags & IFF_RUNNING) == 0)
1112 		return;
1113 
1114 	callout_stop(&sc->sc_brcallout);
1115 	bstp_stop(sc);
1116 
1117 	IF_PURGE(&ifp->if_snd);
1118 
1119 	bridge_rtflush(sc, IFBF_FLUSHDYN);
1120 
1121 	ifp->if_flags &= ~IFF_RUNNING;
1122 }
1123 
1124 /*
1125  * bridge_enqueue:
1126  *
1127  *	Enqueue a packet on a bridge member interface.
1128  *
1129  *	NOTE: must be called at splnet().
1130  */
1131 void
1132 bridge_enqueue(struct bridge_softc *sc, struct ifnet *dst_ifp, struct mbuf *m,
1133     int runfilt)
1134 {
1135 	ALTQ_DECL(struct altq_pktattr pktattr;)
1136 	int len, error;
1137 	short mflags;
1138 
1139 	/*
1140 	 * Clear any in-bound checksum flags for this packet.
1141 	 */
1142 	m->m_pkthdr.csum_flags = 0;
1143 
1144 #ifdef PFIL_HOOKS
1145 	if (runfilt) {
1146 		if (pfil_run_hooks(&sc->sc_if.if_pfil, &m,
1147 		    dst_ifp, PFIL_OUT) != 0) {
1148 			if (m != NULL)
1149 				m_freem(m);
1150 			return;
1151 		}
1152 		if (m == NULL)
1153 			return;
1154 	}
1155 #endif /* PFIL_HOOKS */
1156 
1157 #ifdef ALTQ
1158 	/*
1159 	 * If ALTQ is enabled on the member interface, do
1160 	 * classification; the queueing discipline might
1161 	 * not require classification, but might require
1162 	 * the address family/header pointer in the pktattr.
1163 	 */
1164 	if (ALTQ_IS_ENABLED(&dst_ifp->if_snd)) {
1165 		/* XXX IFT_ETHER */
1166 		altq_etherclassify(&dst_ifp->if_snd, m, &pktattr);
1167 	}
1168 #endif /* ALTQ */
1169 
1170 	len = m->m_pkthdr.len;
1171 	m->m_flags |= M_PROTO1;
1172 	mflags = m->m_flags;
1173 	IFQ_ENQUEUE(&dst_ifp->if_snd, m, &pktattr, error);
1174 	if (error) {
1175 		/* mbuf is already freed */
1176 		sc->sc_if.if_oerrors++;
1177 		return;
1178 	}
1179 
1180 	sc->sc_if.if_opackets++;
1181 	sc->sc_if.if_obytes += len;
1182 
1183 	dst_ifp->if_obytes += len;
1184 
1185 	if (mflags & M_MCAST) {
1186 		sc->sc_if.if_omcasts++;
1187 		dst_ifp->if_omcasts++;
1188 	}
1189 
1190 	if ((dst_ifp->if_flags & IFF_OACTIVE) == 0)
1191 		(*dst_ifp->if_start)(dst_ifp);
1192 }
1193 
1194 /*
1195  * bridge_output:
1196  *
1197  *	Send output from a bridge member interface.  This
1198  *	performs the bridging function for locally originated
1199  *	packets.
1200  *
1201  *	The mbuf has the Ethernet header already attached.  We must
1202  *	enqueue or free the mbuf before returning.
1203  */
1204 int
1205 bridge_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *sa,
1206     struct rtentry *rt)
1207 {
1208 	struct ether_header *eh;
1209 	struct ifnet *dst_if;
1210 	struct bridge_softc *sc;
1211 	int s;
1212 
1213 	if (m->m_len < ETHER_HDR_LEN) {
1214 		m = m_pullup(m, ETHER_HDR_LEN);
1215 		if (m == NULL)
1216 			return (0);
1217 	}
1218 
1219 	eh = mtod(m, struct ether_header *);
1220 	sc = ifp->if_bridge;
1221 
1222 	s = splnet();
1223 
1224 	/*
1225 	 * If bridge is down, but the original output interface is up,
1226 	 * go ahead and send out that interface.  Otherwise, the packet
1227 	 * is dropped below.
1228 	 */
1229 	if ((sc->sc_if.if_flags & IFF_RUNNING) == 0) {
1230 		dst_if = ifp;
1231 		goto sendunicast;
1232 	}
1233 
1234 	/*
1235 	 * If the packet is a multicast, or we don't know a better way to
1236 	 * get there, send to all interfaces.
1237 	 */
1238 	if (ETHER_IS_MULTICAST(eh->ether_dhost))
1239 		dst_if = NULL;
1240 	else
1241 		dst_if = bridge_rtlookup(sc, eh->ether_dhost);
1242 	if (dst_if == NULL) {
1243 		struct bridge_iflist *bif;
1244 		struct mbuf *mc;
1245 		int used = 0;
1246 
1247 		LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
1248 			dst_if = bif->bif_ifp;
1249 			if ((dst_if->if_flags & IFF_RUNNING) == 0)
1250 				continue;
1251 
1252 			/*
1253 			 * If this is not the original output interface,
1254 			 * and the interface is participating in spanning
1255 			 * tree, make sure the port is in a state that
1256 			 * allows forwarding.
1257 			 */
1258 			if (dst_if != ifp &&
1259 			    (bif->bif_flags & IFBIF_STP) != 0) {
1260 				switch (bif->bif_state) {
1261 				case BSTP_IFSTATE_BLOCKING:
1262 				case BSTP_IFSTATE_LISTENING:
1263 				case BSTP_IFSTATE_DISABLED:
1264 					continue;
1265 				}
1266 			}
1267 
1268 			if (LIST_NEXT(bif, bif_next) == NULL) {
1269 				used = 1;
1270 				mc = m;
1271 			} else {
1272 				mc = m_copym(m, 0, M_COPYALL, M_NOWAIT);
1273 				if (mc == NULL) {
1274 					sc->sc_if.if_oerrors++;
1275 					continue;
1276 				}
1277 			}
1278 
1279 			bridge_enqueue(sc, dst_if, mc, 0);
1280 		}
1281 		if (used == 0)
1282 			m_freem(m);
1283 		splx(s);
1284 		return (0);
1285 	}
1286 
1287  sendunicast:
1288 	/*
1289 	 * XXX Spanning tree consideration here?
1290 	 */
1291 
1292 	if ((dst_if->if_flags & IFF_RUNNING) == 0) {
1293 		m_freem(m);
1294 		splx(s);
1295 		return (0);
1296 	}
1297 
1298 	bridge_enqueue(sc, dst_if, m, 0);
1299 
1300 	splx(s);
1301 	return (0);
1302 }
1303 
1304 /*
1305  * bridge_start:
1306  *
1307  *	Start output on a bridge.
1308  *
1309  *	NOTE: This routine should never be called in this implementation.
1310  */
1311 static void
1312 bridge_start(struct ifnet *ifp)
1313 {
1314 
1315 	printf("%s: bridge_start() called\n", ifp->if_xname);
1316 }
1317 
1318 /*
1319  * bridge_forward:
1320  *
1321  *	The forwarding function of the bridge.
1322  */
1323 static void
1324 bridge_forward(struct bridge_softc *sc, struct mbuf *m)
1325 {
1326 	struct bridge_iflist *bif;
1327 	struct ifnet *src_if, *dst_if;
1328 	struct ether_header *eh;
1329 
1330 	src_if = m->m_pkthdr.rcvif;
1331 
1332 	sc->sc_if.if_ipackets++;
1333 	sc->sc_if.if_ibytes += m->m_pkthdr.len;
1334 
1335 	/*
1336 	 * Look up the bridge_iflist.
1337 	 */
1338 	bif = bridge_lookup_member_if(sc, src_if);
1339 	if (bif == NULL) {
1340 		/* Interface is not a bridge member (anymore?) */
1341 		m_freem(m);
1342 		return;
1343 	}
1344 
1345 	if (bif->bif_flags & IFBIF_STP) {
1346 		switch (bif->bif_state) {
1347 		case BSTP_IFSTATE_BLOCKING:
1348 		case BSTP_IFSTATE_LISTENING:
1349 		case BSTP_IFSTATE_DISABLED:
1350 			m_freem(m);
1351 			return;
1352 		}
1353 	}
1354 
1355 	eh = mtod(m, struct ether_header *);
1356 
1357 	/*
1358 	 * If the interface is learning, and the source
1359 	 * address is valid and not multicast, record
1360 	 * the address.
1361 	 */
1362 	if ((bif->bif_flags & IFBIF_LEARNING) != 0 &&
1363 	    ETHER_IS_MULTICAST(eh->ether_shost) == 0 &&
1364 	    (eh->ether_shost[0] == 0 &&
1365 	     eh->ether_shost[1] == 0 &&
1366 	     eh->ether_shost[2] == 0 &&
1367 	     eh->ether_shost[3] == 0 &&
1368 	     eh->ether_shost[4] == 0 &&
1369 	     eh->ether_shost[5] == 0) == 0) {
1370 		(void) bridge_rtupdate(sc, eh->ether_shost,
1371 		    src_if, 0, IFBAF_DYNAMIC);
1372 	}
1373 
1374 	if ((bif->bif_flags & IFBIF_STP) != 0 &&
1375 	    bif->bif_state == BSTP_IFSTATE_LEARNING) {
1376 		m_freem(m);
1377 		return;
1378 	}
1379 
1380 	/*
1381 	 * At this point, the port either doesn't participate
1382 	 * in spanning tree or it is in the forwarding state.
1383 	 */
1384 
1385 	/*
1386 	 * If the packet is unicast, destined for someone on
1387 	 * "this" side of the bridge, drop it.
1388 	 */
1389 	if ((m->m_flags & (M_BCAST|M_MCAST)) == 0) {
1390 		dst_if = bridge_rtlookup(sc, eh->ether_dhost);
1391 		if (src_if == dst_if) {
1392 			m_freem(m);
1393 			return;
1394 		}
1395 	} else {
1396 		/* ...forward it to all interfaces. */
1397 		sc->sc_if.if_imcasts++;
1398 		dst_if = NULL;
1399 	}
1400 
1401 #ifdef PFIL_HOOKS
1402 	if (pfil_run_hooks(&sc->sc_if.if_pfil, &m,
1403 	    m->m_pkthdr.rcvif, PFIL_IN) != 0) {
1404 		if (m != NULL)
1405 			m_freem(m);
1406 		return;
1407 	}
1408 	if (m == NULL)
1409 		return;
1410 #endif /* PFIL_HOOKS */
1411 
1412 	if (dst_if == NULL) {
1413 		bridge_broadcast(sc, src_if, m);
1414 		return;
1415 	}
1416 
1417 	/*
1418 	 * At this point, we're dealing with a unicast frame
1419 	 * going to a different interface.
1420 	 */
1421 	if ((dst_if->if_flags & IFF_RUNNING) == 0) {
1422 		m_freem(m);
1423 		return;
1424 	}
1425 	bif = bridge_lookup_member_if(sc, dst_if);
1426 	if (bif == NULL) {
1427 		/* Not a member of the bridge (anymore?) */
1428 		m_freem(m);
1429 		return;
1430 	}
1431 
1432 	if (bif->bif_flags & IFBIF_STP) {
1433 		switch (bif->bif_state) {
1434 		case BSTP_IFSTATE_DISABLED:
1435 		case BSTP_IFSTATE_BLOCKING:
1436 			m_freem(m);
1437 			return;
1438 		}
1439 	}
1440 
1441 	bridge_enqueue(sc, dst_if, m, 1);
1442 }
1443 
1444 /*
1445  * bridge_input:
1446  *
1447  *	Receive input from a member interface.  Queue the packet for
1448  *	bridging if it is not for us.
1449  */
1450 struct mbuf *
1451 bridge_input(struct ifnet *ifp, struct mbuf *m)
1452 {
1453 	struct bridge_softc *sc = ifp->if_bridge;
1454 	struct bridge_iflist *bif;
1455 	struct ether_header *eh;
1456 	struct mbuf *mc;
1457 
1458 	if ((sc->sc_if.if_flags & IFF_RUNNING) == 0)
1459 		return (m);
1460 
1461 	bif = bridge_lookup_member_if(sc, ifp);
1462 	if (bif == NULL)
1463 		return (m);
1464 
1465 	eh = mtod(m, struct ether_header *);
1466 
1467 	if (m->m_flags & (M_BCAST|M_MCAST)) {
1468 		/* Tap off 802.1D packets; they do not get forwarded. */
1469 		if (memcmp(eh->ether_dhost, bstp_etheraddr,
1470 		    ETHER_ADDR_LEN) == 0) {
1471 			m = bstp_input(ifp, m);
1472 			if (m == NULL)
1473 				return (NULL);
1474 		}
1475 
1476 		if (bif->bif_flags & IFBIF_STP) {
1477 			switch (bif->bif_state) {
1478 			case BSTP_IFSTATE_BLOCKING:
1479 			case BSTP_IFSTATE_LISTENING:
1480 			case BSTP_IFSTATE_DISABLED:
1481 				return (m);
1482 			}
1483 		}
1484 
1485 		/*
1486 		 * Make a deep copy of the packet and enqueue the copy
1487 		 * for bridge processing; return the original packet for
1488 		 * local processing.
1489 		 */
1490 		mc = m_dup(m, 0, M_COPYALL, M_NOWAIT);
1491 		if (mc == NULL)
1492 			return (m);
1493 
1494 		/* Perform the bridge forwarding function with the copy. */
1495 #if NGIF > 0
1496 		if (ifp->if_type == IFT_GIF) {
1497 			LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
1498 				if (bif->bif_ifp->if_type == IFT_ETHER)
1499 				break;
1500 			}
1501 			if (bif != NULL) {
1502 				m->m_flags |= M_PROTO1;
1503 				m->m_pkthdr.rcvif = bif->bif_ifp;
1504 				(*bif->bif_ifp->if_input)(bif->bif_ifp, m);
1505 				m = NULL;
1506 			}
1507 		}
1508 #endif
1509 		bridge_forward(sc, mc);
1510 
1511 		/* Return the original packet for local processing. */
1512 		return (m);
1513 	}
1514 
1515 	if (bif->bif_flags & IFBIF_STP) {
1516 		switch (bif->bif_state) {
1517 		case BSTP_IFSTATE_BLOCKING:
1518 		case BSTP_IFSTATE_LISTENING:
1519 		case BSTP_IFSTATE_DISABLED:
1520 			return (m);
1521 		}
1522 	}
1523 
1524 	/*
1525 	 * Unicast.  Make sure it's not for us.
1526 	 */
1527 	LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
1528 		if(bif->bif_ifp->if_type != IFT_ETHER)
1529 			continue;
1530 		/* It is destined for us. */
1531 		if (memcmp(LLADDR(bif->bif_ifp->if_sadl), eh->ether_dhost,
1532 		    ETHER_ADDR_LEN) == 0) {
1533 			if (bif->bif_flags & IFBIF_LEARNING)
1534 				(void) bridge_rtupdate(sc,
1535 				    eh->ether_shost, ifp, 0, IFBAF_DYNAMIC);
1536 			m->m_pkthdr.rcvif = bif->bif_ifp;
1537 #if NGIF > 0
1538 			if (ifp->if_type == IFT_GIF) {
1539 				m->m_flags |= M_PROTO1;
1540 				m->m_pkthdr.rcvif = bif->bif_ifp;
1541 				(*bif->bif_ifp->if_input)(bif->bif_ifp, m);
1542 				m = NULL;
1543 			}
1544 #endif
1545 			return (m);
1546 		}
1547 
1548 		/* We just received a packet that we sent out. */
1549 		if (memcmp(LLADDR(bif->bif_ifp->if_sadl), eh->ether_shost,
1550 		    ETHER_ADDR_LEN) == 0) {
1551 			m_freem(m);
1552 			return (NULL);
1553 		}
1554 	}
1555 
1556 	/* Perform the bridge forwarding function. */
1557 	bridge_forward(sc, m);
1558 
1559 	return (NULL);
1560 }
1561 
1562 /*
1563  * bridge_broadcast:
1564  *
1565  *	Send a frame to all interfaces that are members of
1566  *	the bridge, except for the one on which the packet
1567  *	arrived.
1568  */
1569 static void
1570 bridge_broadcast(struct bridge_softc *sc, struct ifnet *src_if,
1571     struct mbuf *m)
1572 {
1573 	struct bridge_iflist *bif;
1574 	struct mbuf *mc;
1575 	struct ifnet *dst_if;
1576 	int used = 0;
1577 
1578 	LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
1579 		dst_if = bif->bif_ifp;
1580 		if (dst_if == src_if)
1581 			continue;
1582 
1583 		if (bif->bif_flags & IFBIF_STP) {
1584 			switch (bif->bif_state) {
1585 			case BSTP_IFSTATE_BLOCKING:
1586 			case BSTP_IFSTATE_DISABLED:
1587 				continue;
1588 			}
1589 		}
1590 
1591 		if ((bif->bif_flags & IFBIF_DISCOVER) == 0 &&
1592 		    (m->m_flags & (M_BCAST|M_MCAST)) == 0)
1593 			continue;
1594 
1595 		if ((dst_if->if_flags & IFF_RUNNING) == 0)
1596 			continue;
1597 
1598 		if (LIST_NEXT(bif, bif_next) == NULL) {
1599 			mc = m;
1600 			used = 1;
1601 		} else {
1602 			mc = m_copym(m, 0, M_COPYALL, M_DONTWAIT);
1603 			if (mc == NULL) {
1604 				sc->sc_if.if_oerrors++;
1605 				continue;
1606 			}
1607 		}
1608 
1609 		bridge_enqueue(sc, dst_if, mc, 1);
1610 	}
1611 	if (used == 0)
1612 		m_freem(m);
1613 }
1614 
1615 /*
1616  * bridge_rtupdate:
1617  *
1618  *	Add a bridge routing entry.
1619  */
1620 static int
1621 bridge_rtupdate(struct bridge_softc *sc, const uint8_t *dst,
1622     struct ifnet *dst_if, int setflags, uint8_t flags)
1623 {
1624 	struct bridge_rtnode *brt;
1625 	int error;
1626 
1627 	/*
1628 	 * A route for this destination might already exist.  If so,
1629 	 * update it, otherwise create a new one.
1630 	 */
1631 	if ((brt = bridge_rtnode_lookup(sc, dst)) == NULL) {
1632 		if (sc->sc_brtcnt >= sc->sc_brtmax)
1633 			return (ENOSPC);
1634 
1635 		/*
1636 		 * Allocate a new bridge forwarding node, and
1637 		 * initialize the expiration time and Ethernet
1638 		 * address.
1639 		 */
1640 		brt = pool_get(&bridge_rtnode_pool, PR_NOWAIT);
1641 		if (brt == NULL)
1642 			return (ENOMEM);
1643 
1644 		memset(brt, 0, sizeof(*brt));
1645 		brt->brt_expire = mono_time.tv_sec + sc->sc_brttimeout;
1646 		brt->brt_flags = IFBAF_DYNAMIC;
1647 		memcpy(brt->brt_addr, dst, ETHER_ADDR_LEN);
1648 
1649 		if ((error = bridge_rtnode_insert(sc, brt)) != 0) {
1650 			pool_put(&bridge_rtnode_pool, brt);
1651 			return (error);
1652 		}
1653 	}
1654 
1655 	brt->brt_ifp = dst_if;
1656 	if (setflags) {
1657 		brt->brt_flags = flags;
1658 		brt->brt_expire = (flags & IFBAF_STATIC) ? 0 :
1659 		    mono_time.tv_sec + sc->sc_brttimeout;
1660 	}
1661 
1662 	return (0);
1663 }
1664 
1665 /*
1666  * bridge_rtlookup:
1667  *
1668  *	Lookup the destination interface for an address.
1669  */
1670 static struct ifnet *
1671 bridge_rtlookup(struct bridge_softc *sc, const uint8_t *addr)
1672 {
1673 	struct bridge_rtnode *brt;
1674 
1675 	if ((brt = bridge_rtnode_lookup(sc, addr)) == NULL)
1676 		return (NULL);
1677 
1678 	return (brt->brt_ifp);
1679 }
1680 
1681 /*
1682  * bridge_rttrim:
1683  *
1684  *	Trim the routine table so that we have a number
1685  *	of routing entries less than or equal to the
1686  *	maximum number.
1687  */
1688 static void
1689 bridge_rttrim(struct bridge_softc *sc)
1690 {
1691 	struct bridge_rtnode *brt, *nbrt;
1692 
1693 	/* Make sure we actually need to do this. */
1694 	if (sc->sc_brtcnt <= sc->sc_brtmax)
1695 		return;
1696 
1697 	/* Force an aging cycle; this might trim enough addresses. */
1698 	bridge_rtage(sc);
1699 	if (sc->sc_brtcnt <= sc->sc_brtmax)
1700 		return;
1701 
1702 	for (brt = LIST_FIRST(&sc->sc_rtlist); brt != NULL; brt = nbrt) {
1703 		nbrt = LIST_NEXT(brt, brt_list);
1704 		if ((brt->brt_flags & IFBAF_TYPEMASK) == IFBAF_DYNAMIC) {
1705 			bridge_rtnode_destroy(sc, brt);
1706 			if (sc->sc_brtcnt <= sc->sc_brtmax)
1707 				return;
1708 		}
1709 	}
1710 }
1711 
1712 /*
1713  * bridge_timer:
1714  *
1715  *	Aging timer for the bridge.
1716  */
1717 static void
1718 bridge_timer(void *arg)
1719 {
1720 	struct bridge_softc *sc = arg;
1721 	int s;
1722 
1723 	s = splnet();
1724 	bridge_rtage(sc);
1725 	splx(s);
1726 
1727 	if (sc->sc_if.if_flags & IFF_RUNNING)
1728 		callout_reset(&sc->sc_brcallout,
1729 		    bridge_rtable_prune_period * hz, bridge_timer, sc);
1730 }
1731 
1732 /*
1733  * bridge_rtage:
1734  *
1735  *	Perform an aging cycle.
1736  */
1737 static void
1738 bridge_rtage(struct bridge_softc *sc)
1739 {
1740 	struct bridge_rtnode *brt, *nbrt;
1741 
1742 	for (brt = LIST_FIRST(&sc->sc_rtlist); brt != NULL; brt = nbrt) {
1743 		nbrt = LIST_NEXT(brt, brt_list);
1744 		if ((brt->brt_flags & IFBAF_TYPEMASK) == IFBAF_DYNAMIC) {
1745 			if (mono_time.tv_sec >= brt->brt_expire)
1746 				bridge_rtnode_destroy(sc, brt);
1747 		}
1748 	}
1749 }
1750 
1751 /*
1752  * bridge_rtflush:
1753  *
1754  *	Remove all dynamic addresses from the bridge.
1755  */
1756 static void
1757 bridge_rtflush(struct bridge_softc *sc, int full)
1758 {
1759 	struct bridge_rtnode *brt, *nbrt;
1760 
1761 	for (brt = LIST_FIRST(&sc->sc_rtlist); brt != NULL; brt = nbrt) {
1762 		nbrt = LIST_NEXT(brt, brt_list);
1763 		if (full || (brt->brt_flags & IFBAF_TYPEMASK) == IFBAF_DYNAMIC)
1764 			bridge_rtnode_destroy(sc, brt);
1765 	}
1766 }
1767 
1768 /*
1769  * bridge_rtdaddr:
1770  *
1771  *	Remove an address from the table.
1772  */
1773 static int
1774 bridge_rtdaddr(struct bridge_softc *sc, const uint8_t *addr)
1775 {
1776 	struct bridge_rtnode *brt;
1777 
1778 	if ((brt = bridge_rtnode_lookup(sc, addr)) == NULL)
1779 		return (ENOENT);
1780 
1781 	bridge_rtnode_destroy(sc, brt);
1782 	return (0);
1783 }
1784 
1785 /*
1786  * bridge_rtdelete:
1787  *
1788  *	Delete routes to a speicifc member interface.
1789  */
1790 static void
1791 bridge_rtdelete(struct bridge_softc *sc, struct ifnet *ifp)
1792 {
1793 	struct bridge_rtnode *brt, *nbrt;
1794 
1795 	for (brt = LIST_FIRST(&sc->sc_rtlist); brt != NULL; brt = nbrt) {
1796 		nbrt = LIST_NEXT(brt, brt_list);
1797 		if (brt->brt_ifp == ifp)
1798 			bridge_rtnode_destroy(sc, brt);
1799 	}
1800 }
1801 
1802 /*
1803  * bridge_rtable_init:
1804  *
1805  *	Initialize the route table for this bridge.
1806  */
1807 static int
1808 bridge_rtable_init(struct bridge_softc *sc)
1809 {
1810 	int i;
1811 
1812 	sc->sc_rthash = malloc(sizeof(*sc->sc_rthash) * BRIDGE_RTHASH_SIZE,
1813 	    M_DEVBUF, M_NOWAIT);
1814 	if (sc->sc_rthash == NULL)
1815 		return (ENOMEM);
1816 
1817 	for (i = 0; i < BRIDGE_RTHASH_SIZE; i++)
1818 		LIST_INIT(&sc->sc_rthash[i]);
1819 
1820 	sc->sc_rthash_key = arc4random();
1821 
1822 	LIST_INIT(&sc->sc_rtlist);
1823 
1824 	return (0);
1825 }
1826 
1827 /*
1828  * bridge_rtable_fini:
1829  *
1830  *	Deconstruct the route table for this bridge.
1831  */
1832 static void
1833 bridge_rtable_fini(struct bridge_softc *sc)
1834 {
1835 
1836 	free(sc->sc_rthash, M_DEVBUF);
1837 }
1838 
1839 /*
1840  * The following hash function is adapted from "Hash Functions" by Bob Jenkins
1841  * ("Algorithm Alley", Dr. Dobbs Journal, September 1997).
1842  */
1843 #define	mix(a, b, c)							\
1844 do {									\
1845 	a -= b; a -= c; a ^= (c >> 13);					\
1846 	b -= c; b -= a; b ^= (a << 8);					\
1847 	c -= a; c -= b; c ^= (b >> 13);					\
1848 	a -= b; a -= c; a ^= (c >> 12);					\
1849 	b -= c; b -= a; b ^= (a << 16);					\
1850 	c -= a; c -= b; c ^= (b >> 5);					\
1851 	a -= b; a -= c; a ^= (c >> 3);					\
1852 	b -= c; b -= a; b ^= (a << 10);					\
1853 	c -= a; c -= b; c ^= (b >> 15);					\
1854 } while (/*CONSTCOND*/0)
1855 
1856 static __inline uint32_t
1857 bridge_rthash(struct bridge_softc *sc, const uint8_t *addr)
1858 {
1859 	uint32_t a = 0x9e3779b9, b = 0x9e3779b9, c = sc->sc_rthash_key;
1860 
1861 	b += addr[5] << 8;
1862 	b += addr[4];
1863 	a += addr[3] << 24;
1864 	a += addr[2] << 16;
1865 	a += addr[1] << 8;
1866 	a += addr[0];
1867 
1868 	mix(a, b, c);
1869 
1870 	return (c & BRIDGE_RTHASH_MASK);
1871 }
1872 
1873 #undef mix
1874 
1875 /*
1876  * bridge_rtnode_lookup:
1877  *
1878  *	Look up a bridge route node for the specified destination.
1879  */
1880 static struct bridge_rtnode *
1881 bridge_rtnode_lookup(struct bridge_softc *sc, const uint8_t *addr)
1882 {
1883 	struct bridge_rtnode *brt;
1884 	uint32_t hash;
1885 	int dir;
1886 
1887 	hash = bridge_rthash(sc, addr);
1888 	LIST_FOREACH(brt, &sc->sc_rthash[hash], brt_hash) {
1889 		dir = memcmp(addr, brt->brt_addr, ETHER_ADDR_LEN);
1890 		if (dir == 0)
1891 			return (brt);
1892 		if (dir > 0)
1893 			return (NULL);
1894 	}
1895 
1896 	return (NULL);
1897 }
1898 
1899 /*
1900  * bridge_rtnode_insert:
1901  *
1902  *	Insert the specified bridge node into the route table.  We
1903  *	assume the entry is not already in the table.
1904  */
1905 static int
1906 bridge_rtnode_insert(struct bridge_softc *sc, struct bridge_rtnode *brt)
1907 {
1908 	struct bridge_rtnode *lbrt;
1909 	uint32_t hash;
1910 	int dir;
1911 
1912 	hash = bridge_rthash(sc, brt->brt_addr);
1913 
1914 	lbrt = LIST_FIRST(&sc->sc_rthash[hash]);
1915 	if (lbrt == NULL) {
1916 		LIST_INSERT_HEAD(&sc->sc_rthash[hash], brt, brt_hash);
1917 		goto out;
1918 	}
1919 
1920 	do {
1921 		dir = memcmp(brt->brt_addr, lbrt->brt_addr, ETHER_ADDR_LEN);
1922 		if (dir == 0)
1923 			return (EEXIST);
1924 		if (dir > 0) {
1925 			LIST_INSERT_BEFORE(lbrt, brt, brt_hash);
1926 			goto out;
1927 		}
1928 		if (LIST_NEXT(lbrt, brt_hash) == NULL) {
1929 			LIST_INSERT_AFTER(lbrt, brt, brt_hash);
1930 			goto out;
1931 		}
1932 		lbrt = LIST_NEXT(lbrt, brt_hash);
1933 	} while (lbrt != NULL);
1934 
1935 #ifdef DIAGNOSTIC
1936 	panic("bridge_rtnode_insert: impossible");
1937 #endif
1938 
1939  out:
1940 	LIST_INSERT_HEAD(&sc->sc_rtlist, brt, brt_list);
1941 	sc->sc_brtcnt++;
1942 
1943 	return (0);
1944 }
1945 
1946 /*
1947  * bridge_rtnode_destroy:
1948  *
1949  *	Destroy a bridge rtnode.
1950  */
1951 static void
1952 bridge_rtnode_destroy(struct bridge_softc *sc, struct bridge_rtnode *brt)
1953 {
1954 
1955 	LIST_REMOVE(brt, brt_hash);
1956 
1957 	LIST_REMOVE(brt, brt_list);
1958 	sc->sc_brtcnt--;
1959 	pool_put(&bridge_rtnode_pool, brt);
1960 }
1961 
1962 #if defined(BRIDGE_IPF) && defined(PFIL_HOOKS)
1963 extern struct pfil_head inet_pfil_hook;                 /* XXX */
1964 extern struct pfil_head inet6_pfil_hook;                /* XXX */
1965 
1966 /*
1967  * Send bridge packets through IPF if they are one of the types IPF can deal
1968  * with, or if they are ARP or REVARP.  (IPF will pass ARP and REVARP without
1969  * question.)
1970  */
1971 static int
1972 bridge_ipf(void *arg, struct mbuf **mp, struct ifnet *ifp, int dir)
1973 {
1974 	int snap, error;
1975 	struct ether_header *eh1, eh2;
1976 	struct llc llc1;
1977 	u_int16_t ether_type;
1978 
1979 	snap = 0;
1980 	error = -1;	/* Default error if not error == 0 */
1981 	eh1 = mtod(*mp, struct ether_header *);
1982 	ether_type = ntohs(eh1->ether_type);
1983 
1984 	/*
1985 	 * Check for SNAP/LLC.
1986 	 */
1987         if (ether_type < ETHERMTU) {
1988                 struct llc *llc2 = (struct llc *)(eh1 + 1);
1989 
1990                 if ((*mp)->m_len >= ETHER_HDR_LEN + 8 &&
1991                     llc2->llc_dsap == LLC_SNAP_LSAP &&
1992                     llc2->llc_ssap == LLC_SNAP_LSAP &&
1993                     llc2->llc_control == LLC_UI) {
1994                 	ether_type = htons(llc2->llc_un.type_snap.ether_type);
1995 			snap = 1;
1996                 }
1997         }
1998 
1999 	/*
2000 	 * If we're trying to filter bridge traffic, don't look at anything
2001 	 * other than IP and ARP traffic.  If the filter doesn't understand
2002 	 * IPv6, don't allow IPv6 through the bridge either.  This is lame
2003 	 * since if we really wanted, say, an AppleTalk filter, we are hosed,
2004 	 * but of course we don't have an AppleTalk filter to begin with.
2005 	 * (Note that since IPF doesn't understand ARP it will pass *ALL*
2006 	 * ARP traffic.)
2007 	 */
2008 	switch (ether_type) {
2009 		case ETHERTYPE_ARP:
2010 		case ETHERTYPE_REVARP:
2011 			return 0; /* Automatically pass */
2012 		case ETHERTYPE_IP:
2013 # ifdef INET6
2014 		case ETHERTYPE_IPV6:
2015 # endif /* INET6 */
2016 			break;
2017 		default:
2018 			goto bad;
2019 	}
2020 
2021 	/* Strip off the Ethernet header and keep a copy. */
2022 	m_copydata(*mp, 0, ETHER_HDR_LEN, (caddr_t) &eh2);
2023 	m_adj(*mp, ETHER_HDR_LEN);
2024 
2025 	/* Strip off snap header, if present */
2026 	if (snap) {
2027 		m_copydata(*mp, 0, sizeof(struct llc), (caddr_t) &llc1);
2028 		m_adj(*mp, sizeof(struct llc));
2029 	}
2030 
2031 	/*
2032 	 * Check basic packet sanity and run IPF through pfil.
2033 	 */
2034 	switch (ether_type)
2035 	{
2036 	case ETHERTYPE_IP :
2037 		error = (dir == PFIL_IN) ? bridge_ip_checkbasic(mp) : 0;
2038 		if (error == 0)
2039 			error = pfil_run_hooks(&inet_pfil_hook, mp, ifp, dir);
2040 		break;
2041 # ifdef INET6
2042 	case ETHERTYPE_IPV6 :
2043 		error = (dir == PFIL_IN) ? bridge_ip6_checkbasic(mp) : 0;
2044 		if (error == 0)
2045 			error = pfil_run_hooks(&inet6_pfil_hook, mp, ifp, dir);
2046 		break;
2047 # endif
2048 	default :
2049 		error = 0;
2050 		break;
2051 	}
2052 
2053 	if (*mp == NULL)
2054 		return error;
2055 	if (error != 0)
2056 		goto bad;
2057 
2058 	error = -1;
2059 
2060 	/*
2061 	 * Finally, put everything back the way it was and return
2062 	 */
2063 	if (snap) {
2064 		M_PREPEND(*mp, sizeof(struct llc), M_DONTWAIT);
2065 		if (*mp == NULL)
2066 			return error;
2067 		bcopy(&llc1, mtod(*mp, caddr_t), sizeof(struct llc));
2068 	}
2069 
2070 	M_PREPEND(*mp, ETHER_HDR_LEN, M_DONTWAIT);
2071 	if (*mp == NULL)
2072 		return error;
2073 	bcopy(&eh2, mtod(*mp, caddr_t), ETHER_HDR_LEN);
2074 
2075 	return 0;
2076 
2077     bad:
2078 	m_freem(*mp);
2079 	*mp = NULL;
2080 	return error;
2081 }
2082 
2083 /*
2084  * Perform basic checks on header size since
2085  * IPF assumes ip_input has already processed
2086  * it for it.  Cut-and-pasted from ip_input.c.
2087  * Given how simple the IPv6 version is,
2088  * does the IPv4 version really need to be
2089  * this complicated?
2090  *
2091  * XXX Should we update ipstat here, or not?
2092  * XXX Right now we update ipstat but not
2093  * XXX csum_counter.
2094  */
2095 static int
2096 bridge_ip_checkbasic(struct mbuf **mp)
2097 {
2098 	struct mbuf *m = *mp;
2099 	struct ip *ip;
2100 	int len, hlen;
2101 
2102 	if (*mp == NULL)
2103 		return -1;
2104 
2105 	if (IP_HDR_ALIGNED_P(mtod(m, caddr_t)) == 0) {
2106 		if ((m = m_copyup(m, sizeof(struct ip),
2107 			(max_linkhdr + 3) & ~3)) == NULL) {
2108 			/* XXXJRT new stat, please */
2109 			ipstat.ips_toosmall++;
2110 			goto bad;
2111 		}
2112 	} else if (__predict_false(m->m_len < sizeof (struct ip))) {
2113 		if ((m = m_pullup(m, sizeof (struct ip))) == NULL) {
2114 			ipstat.ips_toosmall++;
2115 			goto bad;
2116 		}
2117 	}
2118 	ip = mtod(m, struct ip *);
2119 	if (ip == NULL) goto bad;
2120 
2121 	if (ip->ip_v != IPVERSION) {
2122 		ipstat.ips_badvers++;
2123 		goto bad;
2124 	}
2125 	hlen = ip->ip_hl << 2;
2126 	if (hlen < sizeof(struct ip)) { /* minimum header length */
2127 		ipstat.ips_badhlen++;
2128 		goto bad;
2129 	}
2130 	if (hlen > m->m_len) {
2131 		if ((m = m_pullup(m, hlen)) == 0) {
2132 			ipstat.ips_badhlen++;
2133 			goto bad;
2134 		}
2135 		ip = mtod(m, struct ip *);
2136 		if (ip == NULL) goto bad;
2137 	}
2138 
2139         switch (m->m_pkthdr.csum_flags &
2140                 ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) |
2141                  M_CSUM_IPv4_BAD)) {
2142         case M_CSUM_IPv4|M_CSUM_IPv4_BAD:
2143                 /* INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad); */
2144                 goto bad;
2145 
2146         case M_CSUM_IPv4:
2147                 /* Checksum was okay. */
2148                 /* INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok); */
2149                 break;
2150 
2151         default:
2152                 /* Must compute it ourselves. */
2153                 /* INET_CSUM_COUNTER_INCR(&ip_swcsum); */
2154                 if (in_cksum(m, hlen) != 0)
2155                         goto bad;
2156                 break;
2157         }
2158 
2159         /* Retrieve the packet length. */
2160         len = ntohs(ip->ip_len);
2161 
2162         /*
2163          * Check for additional length bogosity
2164          */
2165         if (len < hlen) {
2166                 ipstat.ips_badlen++;
2167                 goto bad;
2168         }
2169 
2170         /*
2171          * Check that the amount of data in the buffers
2172          * is as at least much as the IP header would have us expect.
2173          * Drop packet if shorter than we expect.
2174          */
2175         if (m->m_pkthdr.len < len) {
2176                 ipstat.ips_tooshort++;
2177                 goto bad;
2178         }
2179 
2180 	/* Checks out, proceed */
2181 	*mp = m;
2182 	return 0;
2183 
2184     bad:
2185 	*mp = m;
2186 	return -1;
2187 }
2188 
2189 # ifdef INET6
2190 /*
2191  * Same as above, but for IPv6.
2192  * Cut-and-pasted from ip6_input.c.
2193  * XXX Should we update ip6stat, or not?
2194  */
2195 static int
2196 bridge_ip6_checkbasic(struct mbuf **mp)
2197 {
2198 	struct mbuf *m = *mp;
2199 	struct ip6_hdr *ip6;
2200 
2201         /*
2202          * If the IPv6 header is not aligned, slurp it up into a new
2203          * mbuf with space for link headers, in the event we forward
2204          * it.  Otherwise, if it is aligned, make sure the entire base
2205          * IPv6 header is in the first mbuf of the chain.
2206          */
2207         if (IP6_HDR_ALIGNED_P(mtod(m, caddr_t)) == 0) {
2208                 struct ifnet *inifp = m->m_pkthdr.rcvif;
2209                 if ((m = m_copyup(m, sizeof(struct ip6_hdr),
2210                                   (max_linkhdr + 3) & ~3)) == NULL) {
2211                         /* XXXJRT new stat, please */
2212                         ip6stat.ip6s_toosmall++;
2213                         in6_ifstat_inc(inifp, ifs6_in_hdrerr);
2214                         goto bad;
2215                 }
2216         } else if (__predict_false(m->m_len < sizeof(struct ip6_hdr))) {
2217                 struct ifnet *inifp = m->m_pkthdr.rcvif;
2218                 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) {
2219                         ip6stat.ip6s_toosmall++;
2220                         in6_ifstat_inc(inifp, ifs6_in_hdrerr);
2221                         goto bad;
2222                 }
2223         }
2224 
2225         ip6 = mtod(m, struct ip6_hdr *);
2226 
2227         if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
2228                 ip6stat.ip6s_badvers++;
2229                 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr);
2230                 goto bad;
2231         }
2232 
2233 	/* Checks out, proceed */
2234 	*mp = m;
2235 	return 0;
2236 
2237     bad:
2238 	*mp = m;
2239 	return -1;
2240 }
2241 # endif /* INET6 */
2242 #endif /* BRIDGE_IPF && PFIL_HOOKS */
2243