xref: /freebsd/sys/netgraph/ng_ether.c (revision 6af83ee0d2941d18880b6aaa2b4facd1d30c6106)
1 
2 /*
3  * ng_ether.c
4  */
5 
6 /*-
7  * Copyright (c) 1996-2000 Whistle Communications, Inc.
8  * All rights reserved.
9  *
10  * Subject to the following obligations and disclaimer of warranty, use and
11  * redistribution of this software, in source or object code forms, with or
12  * without modifications are expressly permitted by Whistle Communications;
13  * provided, however, that:
14  * 1. Any and all reproductions of the source or object code must include the
15  *    copyright notice above and the following disclaimer of warranties; and
16  * 2. No rights are granted, in any manner or form, to use Whistle
17  *    Communications, Inc. trademarks, including the mark "WHISTLE
18  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
19  *    such appears in the above copyright notice or in the software.
20  *
21  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
22  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
23  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
24  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
26  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
27  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
28  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
29  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
30  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
31  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
32  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
33  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
34  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
36  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
37  * OF SUCH DAMAGE.
38  *
39  * Authors: Archie Cobbs <archie@freebsd.org>
40  *	    Julian Elischer <julian@freebsd.org>
41  *
42  * $FreeBSD$
43  */
44 
45 /*
46  * ng_ether(4) netgraph node type
47  */
48 
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/kernel.h>
52 #include <sys/malloc.h>
53 #include <sys/mbuf.h>
54 #include <sys/errno.h>
55 #include <sys/syslog.h>
56 #include <sys/socket.h>
57 
58 #include <net/bridge.h>
59 #include <net/if.h>
60 #include <net/if_dl.h>
61 #include <net/if_types.h>
62 #include <net/if_arp.h>
63 #include <net/if_var.h>
64 #include <net/ethernet.h>
65 
66 #include <netgraph/ng_message.h>
67 #include <netgraph/netgraph.h>
68 #include <netgraph/ng_parse.h>
69 #include <netgraph/ng_ether.h>
70 
71 #define IFP2NG(ifp)  ((struct ng_node *)((struct arpcom *)(ifp))->ac_netgraph)
72 #define IFP2NG_SET(ifp, val)	(((struct arpcom *)(ifp))->ac_netgraph = (val))
73 
74 /* Per-node private data */
75 struct private {
76 	struct ifnet	*ifp;		/* associated interface */
77 	hook_p		upper;		/* upper hook connection */
78 	hook_p		lower;		/* lower hook connection */
79 	hook_p		orphan;		/* orphan hook connection */
80 	u_char		autoSrcAddr;	/* always overwrite source address */
81 	u_char		promisc;	/* promiscuous mode enabled */
82 	u_long		hwassist;	/* hardware checksum capabilities */
83 	u_int		flags;		/* flags e.g. really die */
84 };
85 typedef struct private *priv_p;
86 
87 /* Hook pointers used by if_ethersubr.c to callback to netgraph */
88 extern	void	(*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp);
89 extern	void	(*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m);
90 extern	int	(*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp);
91 extern	void	(*ng_ether_attach_p)(struct ifnet *ifp);
92 extern	void	(*ng_ether_detach_p)(struct ifnet *ifp);
93 extern	void	(*ng_ether_link_state_p)(struct ifnet *ifp, int state);
94 
95 /* Functional hooks called from if_ethersubr.c */
96 static void	ng_ether_input(struct ifnet *ifp, struct mbuf **mp);
97 static void	ng_ether_input_orphan(struct ifnet *ifp, struct mbuf *m);
98 static int	ng_ether_output(struct ifnet *ifp, struct mbuf **mp);
99 static void	ng_ether_attach(struct ifnet *ifp);
100 static void	ng_ether_detach(struct ifnet *ifp);
101 static void	ng_ether_link_state(struct ifnet *ifp, int state);
102 
103 /* Other functions */
104 static int	ng_ether_rcv_lower(node_p node, struct mbuf *m);
105 static int	ng_ether_rcv_upper(node_p node, struct mbuf *m);
106 
107 /* Netgraph node methods */
108 static ng_constructor_t	ng_ether_constructor;
109 static ng_rcvmsg_t	ng_ether_rcvmsg;
110 static ng_shutdown_t	ng_ether_shutdown;
111 static ng_newhook_t	ng_ether_newhook;
112 static ng_connect_t	ng_ether_connect;
113 static ng_rcvdata_t	ng_ether_rcvdata;
114 static ng_disconnect_t	ng_ether_disconnect;
115 static int		ng_ether_mod_event(module_t mod, int event, void *data);
116 
117 /* List of commands and how to convert arguments to/from ASCII */
118 static const struct ng_cmdlist ng_ether_cmdlist[] = {
119 	{
120 	  NGM_ETHER_COOKIE,
121 	  NGM_ETHER_GET_IFNAME,
122 	  "getifname",
123 	  NULL,
124 	  &ng_parse_string_type
125 	},
126 	{
127 	  NGM_ETHER_COOKIE,
128 	  NGM_ETHER_GET_IFINDEX,
129 	  "getifindex",
130 	  NULL,
131 	  &ng_parse_int32_type
132 	},
133 	{
134 	  NGM_ETHER_COOKIE,
135 	  NGM_ETHER_GET_ENADDR,
136 	  "getenaddr",
137 	  NULL,
138 	  &ng_parse_enaddr_type
139 	},
140 	{
141 	  NGM_ETHER_COOKIE,
142 	  NGM_ETHER_SET_ENADDR,
143 	  "setenaddr",
144 	  &ng_parse_enaddr_type,
145 	  NULL
146 	},
147 	{
148 	  NGM_ETHER_COOKIE,
149 	  NGM_ETHER_GET_PROMISC,
150 	  "getpromisc",
151 	  NULL,
152 	  &ng_parse_int32_type
153 	},
154 	{
155 	  NGM_ETHER_COOKIE,
156 	  NGM_ETHER_SET_PROMISC,
157 	  "setpromisc",
158 	  &ng_parse_int32_type,
159 	  NULL
160 	},
161 	{
162 	  NGM_ETHER_COOKIE,
163 	  NGM_ETHER_GET_AUTOSRC,
164 	  "getautosrc",
165 	  NULL,
166 	  &ng_parse_int32_type
167 	},
168 	{
169 	  NGM_ETHER_COOKIE,
170 	  NGM_ETHER_SET_AUTOSRC,
171 	  "setautosrc",
172 	  &ng_parse_int32_type,
173 	  NULL
174 	},
175 	{
176 	  NGM_ETHER_COOKIE,
177 	  NGM_ETHER_ADD_MULTI,
178 	  "addmulti",
179 	  &ng_parse_enaddr_type,
180 	  NULL
181 	},
182 	{
183 	  NGM_ETHER_COOKIE,
184 	  NGM_ETHER_DEL_MULTI,
185 	  "delmulti",
186 	  &ng_parse_enaddr_type,
187 	  NULL
188 	},
189 	{ 0 }
190 };
191 
192 static struct ng_type ng_ether_typestruct = {
193 	.version =	NG_ABI_VERSION,
194 	.name =		NG_ETHER_NODE_TYPE,
195 	.mod_event =	ng_ether_mod_event,
196 	.constructor =	ng_ether_constructor,
197 	.rcvmsg =	ng_ether_rcvmsg,
198 	.shutdown =	ng_ether_shutdown,
199 	.newhook =	ng_ether_newhook,
200 	.connect =	ng_ether_connect,
201 	.rcvdata =	ng_ether_rcvdata,
202 	.disconnect =	ng_ether_disconnect,
203 	.cmdlist =	ng_ether_cmdlist,
204 };
205 NETGRAPH_INIT(ether, &ng_ether_typestruct);
206 
207 /******************************************************************
208 		    ETHERNET FUNCTION HOOKS
209 ******************************************************************/
210 
211 /*
212  * Handle a packet that has come in on an interface. We get to
213  * look at it here before any upper layer protocols do.
214  *
215  * NOTE: this function will get called at splimp()
216  */
217 static void
218 ng_ether_input(struct ifnet *ifp, struct mbuf **mp)
219 {
220 	const node_p node = IFP2NG(ifp);
221 	const priv_p priv = NG_NODE_PRIVATE(node);
222 	int error;
223 
224 	/* If "lower" hook not connected, let packet continue */
225 	if (priv->lower == NULL)
226 		return;
227 	NG_SEND_DATA_ONLY(error, priv->lower, *mp);	/* sets *mp = NULL */
228 }
229 
230 /*
231  * Handle a packet that has come in on an interface, and which
232  * does not match any of our known protocols (an ``orphan'').
233  *
234  * NOTE: this function will get called at splimp()
235  */
236 static void
237 ng_ether_input_orphan(struct ifnet *ifp, struct mbuf *m)
238 {
239 	const node_p node = IFP2NG(ifp);
240 	const priv_p priv = NG_NODE_PRIVATE(node);
241 	int error;
242 
243 	/* If "orphan" hook not connected, discard packet */
244 	if (priv->orphan == NULL) {
245 		m_freem(m);
246 		return;
247 	}
248 	NG_SEND_DATA_ONLY(error, priv->orphan, m);
249 }
250 
251 /*
252  * Handle a packet that is going out on an interface.
253  * The Ethernet header is already attached to the mbuf.
254  */
255 static int
256 ng_ether_output(struct ifnet *ifp, struct mbuf **mp)
257 {
258 	const node_p node = IFP2NG(ifp);
259 	const priv_p priv = NG_NODE_PRIVATE(node);
260 	int error = 0;
261 
262 	/* If "upper" hook not connected, let packet continue */
263 	if (priv->upper == NULL)
264 		return (0);
265 
266 	/* Send it out "upper" hook */
267 	NG_SEND_DATA_ONLY(error, priv->upper, *mp);
268 	return (error);
269 }
270 
271 /*
272  * A new Ethernet interface has been attached.
273  * Create a new node for it, etc.
274  */
275 static void
276 ng_ether_attach(struct ifnet *ifp)
277 {
278 	priv_p priv;
279 	node_p node;
280 
281 	/* Create node */
282 	KASSERT(!IFP2NG(ifp), ("%s: node already exists?", __func__));
283 	if (ng_make_node_common(&ng_ether_typestruct, &node) != 0) {
284 		log(LOG_ERR, "%s: can't %s for %s\n",
285 		    __func__, "create node", ifp->if_xname);
286 		return;
287 	}
288 
289 	/* Allocate private data */
290 	MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
291 	if (priv == NULL) {
292 		log(LOG_ERR, "%s: can't %s for %s\n",
293 		    __func__, "allocate memory", ifp->if_xname);
294 		NG_NODE_UNREF(node);
295 		return;
296 	}
297 	NG_NODE_SET_PRIVATE(node, priv);
298 	priv->ifp = ifp;
299 	IFP2NG_SET(ifp, node);
300 	priv->autoSrcAddr = 1;
301 	priv->hwassist = ifp->if_hwassist;
302 
303 	/* Try to give the node the same name as the interface */
304 	if (ng_name_node(node, ifp->if_xname) != 0) {
305 		log(LOG_WARNING, "%s: can't name node %s\n",
306 		    __func__, ifp->if_xname);
307 	}
308 }
309 
310 /*
311  * An Ethernet interface is being detached.
312  * REALLY Destroy its node.
313  */
314 static void
315 ng_ether_detach(struct ifnet *ifp)
316 {
317 	const node_p node = IFP2NG(ifp);
318 	const priv_p priv = NG_NODE_PRIVATE(node);
319 
320 	NG_NODE_REALLY_DIE(node);	/* Force real removal of node */
321 	/*
322 	 * We can't assume the ifnet is still around when we run shutdown
323 	 * So zap it now. XXX We HOPE that anything running at this time
324 	 * handles it (as it should in the non netgraph case).
325 	 */
326 	IFP2NG_SET(ifp, NULL);
327 	priv->ifp = NULL;	/* XXX race if interrupted an output packet */
328 	ng_rmnode_self(node);		/* remove all netgraph parts */
329 }
330 
331 /*
332  * Notify graph about link event.
333  * if_link_state_change() has already checked that the state has changed.
334  */
335 static void
336 ng_ether_link_state(struct ifnet *ifp, int state)
337 {
338 	const node_p node = IFP2NG(ifp);
339 	const priv_p priv = NG_NODE_PRIVATE(node);
340 	struct ng_mesg *msg;
341 	int cmd, dummy_error = 0;
342 
343 	if (priv->lower == NULL)
344                 return;
345 
346 	if (state == LINK_STATE_UP)
347 		cmd = NGM_LINK_IS_UP;
348 	else if (state == LINK_STATE_DOWN)
349 		cmd = NGM_LINK_IS_DOWN;
350 	else
351 		return;
352 
353 	NG_MKMESSAGE(msg, NGM_FLOW_COOKIE, cmd, 0, M_NOWAIT);
354 	if (msg != NULL)
355 		NG_SEND_MSG_HOOK(dummy_error, node, msg, priv->lower, 0);
356 }
357 
358 /******************************************************************
359 		    NETGRAPH NODE METHODS
360 ******************************************************************/
361 
362 /*
363  * It is not possible or allowable to create a node of this type.
364  * Nodes get created when the interface is attached (or, when
365  * this node type's KLD is loaded).
366  */
367 static int
368 ng_ether_constructor(node_p node)
369 {
370 	return (EINVAL);
371 }
372 
373 /*
374  * Check for attaching a new hook.
375  */
376 static	int
377 ng_ether_newhook(node_p node, hook_p hook, const char *name)
378 {
379 	const priv_p priv = NG_NODE_PRIVATE(node);
380 	hook_p *hookptr;
381 
382 	/* Divert hook is an alias for lower */
383 	if (strcmp(name, NG_ETHER_HOOK_DIVERT) == 0)
384 		name = NG_ETHER_HOOK_LOWER;
385 
386 	/* Which hook? */
387 	if (strcmp(name, NG_ETHER_HOOK_UPPER) == 0)
388 		hookptr = &priv->upper;
389 	else if (strcmp(name, NG_ETHER_HOOK_LOWER) == 0)
390 		hookptr = &priv->lower;
391 	else if (strcmp(name, NG_ETHER_HOOK_ORPHAN) == 0)
392 		hookptr = &priv->orphan;
393 	else
394 		return (EINVAL);
395 
396 	/* Check if already connected (shouldn't be, but doesn't hurt) */
397 	if (*hookptr != NULL)
398 		return (EISCONN);
399 
400 	/* Disable hardware checksums while 'upper' hook is connected */
401 	if (hookptr == &priv->upper)
402 		priv->ifp->if_hwassist = 0;
403 
404 	/* OK */
405 	*hookptr = hook;
406 	return (0);
407 }
408 
409 /*
410  * Hooks are attached, adjust to force queueing.
411  * We don't really care which hook it is.
412  * they should all be queuing for outgoing data.
413  */
414 static	int
415 ng_ether_connect(hook_p hook)
416 {
417 	NG_HOOK_FORCE_QUEUE(NG_HOOK_PEER(hook));
418 	return (0);
419 }
420 
421 /*
422  * Receive an incoming control message.
423  */
424 static int
425 ng_ether_rcvmsg(node_p node, item_p item, hook_p lasthook)
426 {
427 	const priv_p priv = NG_NODE_PRIVATE(node);
428 	struct ng_mesg *resp = NULL;
429 	int error = 0;
430 	struct ng_mesg *msg;
431 
432 	NGI_GET_MSG(item, msg);
433 	switch (msg->header.typecookie) {
434 	case NGM_ETHER_COOKIE:
435 		switch (msg->header.cmd) {
436 		case NGM_ETHER_GET_IFNAME:
437 			NG_MKRESPONSE(resp, msg, IFNAMSIZ, M_NOWAIT);
438 			if (resp == NULL) {
439 				error = ENOMEM;
440 				break;
441 			}
442 			strlcpy(resp->data, priv->ifp->if_xname, IFNAMSIZ);
443 			break;
444 		case NGM_ETHER_GET_IFINDEX:
445 			NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
446 			if (resp == NULL) {
447 				error = ENOMEM;
448 				break;
449 			}
450 			*((u_int32_t *)resp->data) = priv->ifp->if_index;
451 			break;
452 		case NGM_ETHER_GET_ENADDR:
453 			NG_MKRESPONSE(resp, msg, ETHER_ADDR_LEN, M_NOWAIT);
454 			if (resp == NULL) {
455 				error = ENOMEM;
456 				break;
457 			}
458 			bcopy((IFP2AC(priv->ifp))->ac_enaddr,
459 			    resp->data, ETHER_ADDR_LEN);
460 			break;
461 		case NGM_ETHER_SET_ENADDR:
462 		    {
463 			if (msg->header.arglen != ETHER_ADDR_LEN) {
464 				error = EINVAL;
465 				break;
466 			}
467 			error = if_setlladdr(priv->ifp,
468 			    (u_char *)msg->data, ETHER_ADDR_LEN);
469 			break;
470 		    }
471 		case NGM_ETHER_GET_PROMISC:
472 			NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
473 			if (resp == NULL) {
474 				error = ENOMEM;
475 				break;
476 			}
477 			*((u_int32_t *)resp->data) = priv->promisc;
478 			break;
479 		case NGM_ETHER_SET_PROMISC:
480 		    {
481 			u_char want;
482 
483 			if (msg->header.arglen != sizeof(u_int32_t)) {
484 				error = EINVAL;
485 				break;
486 			}
487 			want = !!*((u_int32_t *)msg->data);
488 			if (want ^ priv->promisc) {
489 				if ((error = ifpromisc(priv->ifp, want)) != 0)
490 					break;
491 				priv->promisc = want;
492 			}
493 			break;
494 		    }
495 		case NGM_ETHER_GET_AUTOSRC:
496 			NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
497 			if (resp == NULL) {
498 				error = ENOMEM;
499 				break;
500 			}
501 			*((u_int32_t *)resp->data) = priv->autoSrcAddr;
502 			break;
503 		case NGM_ETHER_SET_AUTOSRC:
504 			if (msg->header.arglen != sizeof(u_int32_t)) {
505 				error = EINVAL;
506 				break;
507 			}
508 			priv->autoSrcAddr = !!*((u_int32_t *)msg->data);
509 			break;
510 		case NGM_ETHER_ADD_MULTI:
511 		    {
512 			struct sockaddr_dl sa_dl;
513 			struct ifmultiaddr *ifm;
514 
515 			if (msg->header.arglen != ETHER_ADDR_LEN) {
516 				error = EINVAL;
517 				break;
518 			}
519 			bzero(&sa_dl, sizeof(struct sockaddr_dl));
520 			sa_dl.sdl_len = sizeof(struct sockaddr_dl);
521 			sa_dl.sdl_family = AF_LINK;
522 			sa_dl.sdl_alen = ETHER_ADDR_LEN;
523 			bcopy((void *)msg->data, LLADDR(&sa_dl),
524 			    ETHER_ADDR_LEN);
525 			error = if_addmulti(priv->ifp,
526 			    (struct sockaddr *)&sa_dl, &ifm);
527 			break;
528 		    }
529 		case NGM_ETHER_DEL_MULTI:
530 		    {
531 			struct sockaddr_dl sa_dl;
532 
533 			if (msg->header.arglen != ETHER_ADDR_LEN) {
534 				error = EINVAL;
535 				break;
536 			}
537 			bzero(&sa_dl, sizeof(struct sockaddr_dl));
538 			sa_dl.sdl_len = sizeof(struct sockaddr_dl);
539 			sa_dl.sdl_family = AF_LINK;
540 			sa_dl.sdl_alen = ETHER_ADDR_LEN;
541 			bcopy((void *)msg->data, LLADDR(&sa_dl),
542 			    ETHER_ADDR_LEN);
543 			error = if_delmulti(priv->ifp,
544 			    (struct sockaddr *)&sa_dl);
545 			break;
546 		    }
547 		default:
548 			error = EINVAL;
549 			break;
550 		}
551 		break;
552 	default:
553 		error = EINVAL;
554 		break;
555 	}
556 	NG_RESPOND_MSG(error, node, item, resp);
557 	NG_FREE_MSG(msg);
558 	return (error);
559 }
560 
561 /*
562  * Receive data on a hook.
563  */
564 static int
565 ng_ether_rcvdata(hook_p hook, item_p item)
566 {
567 	const node_p node = NG_HOOK_NODE(hook);
568 	const priv_p priv = NG_NODE_PRIVATE(node);
569 	struct mbuf *m;
570 
571 	NGI_GET_M(item, m);
572 	NG_FREE_ITEM(item);
573 
574 	if (hook == priv->lower || hook == priv->orphan)
575 		return ng_ether_rcv_lower(node, m);
576 	if (hook == priv->upper)
577 		return ng_ether_rcv_upper(node, m);
578 	panic("%s: weird hook", __func__);
579 #ifdef RESTARTABLE_PANICS /* so we don't get an error msg in LINT */
580 	return (0);
581 #endif
582 }
583 
584 /*
585  * Handle an mbuf received on the "lower" or "orphan" hook.
586  */
587 static int
588 ng_ether_rcv_lower(node_p node, struct mbuf *m)
589 {
590 	const priv_p priv = NG_NODE_PRIVATE(node);
591  	struct ifnet *const ifp = priv->ifp;
592 
593 	/* Check whether interface is ready for packets */
594 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) {
595 		NG_FREE_M(m);
596 		return (ENETDOWN);
597 	}
598 
599 	/* Make sure header is fully pulled up */
600 	if (m->m_pkthdr.len < sizeof(struct ether_header)) {
601 		NG_FREE_M(m);
602 		return (EINVAL);
603 	}
604 	if (m->m_len < sizeof(struct ether_header)
605 	    && (m = m_pullup(m, sizeof(struct ether_header))) == NULL)
606 		return (ENOBUFS);
607 
608 	/* Drop in the MAC address if desired */
609 	if (priv->autoSrcAddr) {
610 
611 		/* Make the mbuf writable if it's not already */
612 		if (!M_WRITABLE(m)
613 		    && (m = m_pullup(m, sizeof(struct ether_header))) == NULL)
614 			return (ENOBUFS);
615 
616 		/* Overwrite source MAC address */
617 		bcopy((IFP2AC(ifp))->ac_enaddr,
618 		    mtod(m, struct ether_header *)->ether_shost,
619 		    ETHER_ADDR_LEN);
620 	}
621 
622 	/* Send it on its way */
623 	return ether_output_frame(ifp, m);
624 }
625 
626 /*
627  * Handle an mbuf received on the "upper" hook.
628  */
629 static int
630 ng_ether_rcv_upper(node_p node, struct mbuf *m)
631 {
632 	const priv_p priv = NG_NODE_PRIVATE(node);
633 
634 	m->m_pkthdr.rcvif = priv->ifp;
635 
636 	if (BDG_ACTIVE(priv->ifp) )
637 		if ((m = bridge_in_ptr(priv->ifp, m)) == NULL)
638 			return (0);
639 
640 	/* Route packet back in */
641 	ether_demux(priv->ifp, m);
642 	return (0);
643 }
644 
645 /*
646  * Shutdown node. This resets the node but does not remove it
647  * unless the REALLY_DIE flag is set.
648  */
649 static int
650 ng_ether_shutdown(node_p node)
651 {
652 	const priv_p priv = NG_NODE_PRIVATE(node);
653 
654 	if (node->nd_flags & NGF_REALLY_DIE) {
655 		/*
656 		 * WE came here because the ethernet card is being unloaded,
657 		 * so stop being persistant.
658 		 * Actually undo all the things we did on creation.
659 		 * Assume the ifp has already been freed.
660 		 */
661 		NG_NODE_SET_PRIVATE(node, NULL);
662 		FREE(priv, M_NETGRAPH);
663 		NG_NODE_UNREF(node);	/* free node itself */
664 		return (0);
665 	}
666 	if (priv->promisc) {		/* disable promiscuous mode */
667 		(void)ifpromisc(priv->ifp, 0);
668 		priv->promisc = 0;
669 	}
670 	priv->autoSrcAddr = 1;		/* reset auto-src-addr flag */
671 	NG_NODE_REVIVE(node);		/* Signal ng_rmnode we are persisant */
672 
673 	return (0);
674 }
675 
676 /*
677  * Hook disconnection.
678  */
679 static int
680 ng_ether_disconnect(hook_p hook)
681 {
682 	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
683 
684 	if (hook == priv->upper) {
685 		priv->upper = NULL;
686 		if (priv->ifp != NULL)		/* restore h/w csum */
687 			priv->ifp->if_hwassist = priv->hwassist;
688 	} else if (hook == priv->lower)
689 		priv->lower = NULL;
690 	else if (hook == priv->orphan)
691 		priv->orphan = NULL;
692 	else
693 		panic("%s: weird hook", __func__);
694 	if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
695 	&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
696 		ng_rmnode_self(NG_HOOK_NODE(hook));	/* reset node */
697 	return (0);
698 }
699 
700 /******************************************************************
701 		    	INITIALIZATION
702 ******************************************************************/
703 
704 /*
705  * Handle loading and unloading for this node type.
706  */
707 static int
708 ng_ether_mod_event(module_t mod, int event, void *data)
709 {
710 	struct ifnet *ifp;
711 	int error = 0;
712 	int s;
713 
714 	s = splnet();
715 	switch (event) {
716 	case MOD_LOAD:
717 
718 		/* Register function hooks */
719 		if (ng_ether_attach_p != NULL) {
720 			error = EEXIST;
721 			break;
722 		}
723 		ng_ether_attach_p = ng_ether_attach;
724 		ng_ether_detach_p = ng_ether_detach;
725 		ng_ether_output_p = ng_ether_output;
726 		ng_ether_input_p = ng_ether_input;
727 		ng_ether_input_orphan_p = ng_ether_input_orphan;
728 		ng_ether_link_state_p = ng_ether_link_state;
729 
730 		/* Create nodes for any already-existing Ethernet interfaces */
731 		IFNET_RLOCK();
732 		TAILQ_FOREACH(ifp, &ifnet, if_link) {
733 			if (ifp->if_type == IFT_ETHER
734 			    || ifp->if_type == IFT_L2VLAN)
735 				ng_ether_attach(ifp);
736 		}
737 		IFNET_RUNLOCK();
738 		break;
739 
740 	case MOD_UNLOAD:
741 
742 		/*
743 		 * Note that the base code won't try to unload us until
744 		 * all nodes have been removed, and that can't happen
745 		 * until all Ethernet interfaces are removed. In any
746 		 * case, we know there are no nodes left if the action
747 		 * is MOD_UNLOAD, so there's no need to detach any nodes.
748 		 */
749 
750 		/* Unregister function hooks */
751 		ng_ether_attach_p = NULL;
752 		ng_ether_detach_p = NULL;
753 		ng_ether_output_p = NULL;
754 		ng_ether_input_p = NULL;
755 		ng_ether_input_orphan_p = NULL;
756 		ng_ether_link_state_p = NULL;
757 		break;
758 
759 	default:
760 		error = EOPNOTSUPP;
761 		break;
762 	}
763 	splx(s);
764 	return (error);
765 }
766 
767