xref: /freebsd/sys/netgraph/ng_ether.c (revision ce6a89e27cd190313be39bb479880aeda4778436)
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/eventhandler.h>
51 #include <sys/systm.h>
52 #include <sys/kernel.h>
53 #include <sys/malloc.h>
54 #include <sys/mbuf.h>
55 #include <sys/errno.h>
56 #include <sys/proc.h>
57 #include <sys/syslog.h>
58 #include <sys/socket.h>
59 #include <sys/taskqueue.h>
60 
61 #include <net/if.h>
62 #include <net/if_dl.h>
63 #include <net/if_types.h>
64 #include <net/if_arp.h>
65 #include <net/if_var.h>
66 #include <net/ethernet.h>
67 #include <net/if_bridgevar.h>
68 #include <net/vnet.h>
69 
70 #include <netgraph/ng_message.h>
71 #include <netgraph/netgraph.h>
72 #include <netgraph/ng_parse.h>
73 #include <netgraph/ng_ether.h>
74 
75 MODULE_VERSION(ng_ether, 1);
76 
77 #define IFP2NG(ifp)  ((ifp)->if_l2com)
78 
79 /* Per-node private data */
80 struct private {
81 	struct ifnet	*ifp;		/* associated interface */
82 	hook_p		upper;		/* upper hook connection */
83 	hook_p		lower;		/* lower hook connection */
84 	hook_p		orphan;		/* orphan hook connection */
85 	u_char		autoSrcAddr;	/* always overwrite source address */
86 	u_char		promisc;	/* promiscuous mode enabled */
87 	u_long		hwassist;	/* hardware checksum capabilities */
88 	u_int		flags;		/* flags e.g. really die */
89 };
90 typedef struct private *priv_p;
91 
92 /* Hook pointers used by if_ethersubr.c to callback to netgraph */
93 extern	void	(*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp);
94 extern	void	(*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m);
95 extern	int	(*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp);
96 extern	void	(*ng_ether_attach_p)(struct ifnet *ifp);
97 extern	void	(*ng_ether_detach_p)(struct ifnet *ifp);
98 extern	void	(*ng_ether_link_state_p)(struct ifnet *ifp, int state);
99 
100 /* Functional hooks called from if_ethersubr.c */
101 static void	ng_ether_input(struct ifnet *ifp, struct mbuf **mp);
102 static void	ng_ether_input_orphan(struct ifnet *ifp, struct mbuf *m);
103 static int	ng_ether_output(struct ifnet *ifp, struct mbuf **mp);
104 static void	ng_ether_attach(struct ifnet *ifp);
105 static void	ng_ether_detach(struct ifnet *ifp);
106 static void	ng_ether_link_state(struct ifnet *ifp, int state);
107 
108 /* Other functions */
109 static int	ng_ether_rcv_lower(hook_p node, item_p item);
110 static int	ng_ether_rcv_upper(hook_p node, item_p item);
111 
112 /* Netgraph node methods */
113 static ng_constructor_t	ng_ether_constructor;
114 static ng_rcvmsg_t	ng_ether_rcvmsg;
115 static ng_shutdown_t	ng_ether_shutdown;
116 static ng_newhook_t	ng_ether_newhook;
117 static ng_rcvdata_t	ng_ether_rcvdata;
118 static ng_disconnect_t	ng_ether_disconnect;
119 static int		ng_ether_mod_event(module_t mod, int event, void *data);
120 
121 static eventhandler_tag	ng_ether_ifnet_arrival_cookie;
122 
123 /* List of commands and how to convert arguments to/from ASCII */
124 static const struct ng_cmdlist ng_ether_cmdlist[] = {
125 	{
126 	  NGM_ETHER_COOKIE,
127 	  NGM_ETHER_GET_IFNAME,
128 	  "getifname",
129 	  NULL,
130 	  &ng_parse_string_type
131 	},
132 	{
133 	  NGM_ETHER_COOKIE,
134 	  NGM_ETHER_GET_IFINDEX,
135 	  "getifindex",
136 	  NULL,
137 	  &ng_parse_int32_type
138 	},
139 	{
140 	  NGM_ETHER_COOKIE,
141 	  NGM_ETHER_GET_ENADDR,
142 	  "getenaddr",
143 	  NULL,
144 	  &ng_parse_enaddr_type
145 	},
146 	{
147 	  NGM_ETHER_COOKIE,
148 	  NGM_ETHER_SET_ENADDR,
149 	  "setenaddr",
150 	  &ng_parse_enaddr_type,
151 	  NULL
152 	},
153 	{
154 	  NGM_ETHER_COOKIE,
155 	  NGM_ETHER_GET_PROMISC,
156 	  "getpromisc",
157 	  NULL,
158 	  &ng_parse_int32_type
159 	},
160 	{
161 	  NGM_ETHER_COOKIE,
162 	  NGM_ETHER_SET_PROMISC,
163 	  "setpromisc",
164 	  &ng_parse_int32_type,
165 	  NULL
166 	},
167 	{
168 	  NGM_ETHER_COOKIE,
169 	  NGM_ETHER_GET_AUTOSRC,
170 	  "getautosrc",
171 	  NULL,
172 	  &ng_parse_int32_type
173 	},
174 	{
175 	  NGM_ETHER_COOKIE,
176 	  NGM_ETHER_SET_AUTOSRC,
177 	  "setautosrc",
178 	  &ng_parse_int32_type,
179 	  NULL
180 	},
181 	{
182 	  NGM_ETHER_COOKIE,
183 	  NGM_ETHER_ADD_MULTI,
184 	  "addmulti",
185 	  &ng_parse_enaddr_type,
186 	  NULL
187 	},
188 	{
189 	  NGM_ETHER_COOKIE,
190 	  NGM_ETHER_DEL_MULTI,
191 	  "delmulti",
192 	  &ng_parse_enaddr_type,
193 	  NULL
194 	},
195 	{
196 	  NGM_ETHER_COOKIE,
197 	  NGM_ETHER_DETACH,
198 	  "detach",
199 	  NULL,
200 	  NULL
201 	},
202 	{ 0 }
203 };
204 
205 static struct ng_type ng_ether_typestruct = {
206 	.version =	NG_ABI_VERSION,
207 	.name =		NG_ETHER_NODE_TYPE,
208 	.mod_event =	ng_ether_mod_event,
209 	.constructor =	ng_ether_constructor,
210 	.rcvmsg =	ng_ether_rcvmsg,
211 	.shutdown =	ng_ether_shutdown,
212 	.newhook =	ng_ether_newhook,
213 	.rcvdata =	ng_ether_rcvdata,
214 	.disconnect =	ng_ether_disconnect,
215 	.cmdlist =	ng_ether_cmdlist,
216 };
217 NETGRAPH_INIT(ether, &ng_ether_typestruct);
218 
219 /******************************************************************
220 		    UTILITY FUNCTIONS
221 ******************************************************************/
222 static void
223 ng_ether_sanitize_ifname(const char *ifname, char *name)
224 {
225 	int i;
226 
227 	for (i = 0; i < IFNAMSIZ; i++) {
228 		if (ifname[i] == '.' || ifname[i] == ':')
229 			name[i] = '_';
230 		else
231 			name[i] = ifname[i];
232 		if (name[i] == '\0')
233 			break;
234 	}
235 }
236 
237 /******************************************************************
238 		    ETHERNET FUNCTION HOOKS
239 ******************************************************************/
240 
241 /*
242  * Handle a packet that has come in on an interface. We get to
243  * look at it here before any upper layer protocols do.
244  */
245 static void
246 ng_ether_input(struct ifnet *ifp, struct mbuf **mp)
247 {
248 	const node_p node = IFP2NG(ifp);
249 	const priv_p priv = NG_NODE_PRIVATE(node);
250 	int error;
251 
252 	/* If "lower" hook not connected, let packet continue */
253 	if (priv->lower == NULL)
254 		return;
255 	NG_SEND_DATA_ONLY(error, priv->lower, *mp);	/* sets *mp = NULL */
256 }
257 
258 /*
259  * Handle a packet that has come in on an interface, and which
260  * does not match any of our known protocols (an ``orphan'').
261  */
262 static void
263 ng_ether_input_orphan(struct ifnet *ifp, struct mbuf *m)
264 {
265 	const node_p node = IFP2NG(ifp);
266 	const priv_p priv = NG_NODE_PRIVATE(node);
267 	int error;
268 
269 	/* If "orphan" hook not connected, discard packet */
270 	if (priv->orphan == NULL) {
271 		m_freem(m);
272 		return;
273 	}
274 	NG_SEND_DATA_ONLY(error, priv->orphan, m);
275 }
276 
277 /*
278  * Handle a packet that is going out on an interface.
279  * The Ethernet header is already attached to the mbuf.
280  */
281 static int
282 ng_ether_output(struct ifnet *ifp, struct mbuf **mp)
283 {
284 	const node_p node = IFP2NG(ifp);
285 	const priv_p priv = NG_NODE_PRIVATE(node);
286 	int error = 0;
287 
288 	/* If "upper" hook not connected, let packet continue */
289 	if (priv->upper == NULL)
290 		return (0);
291 
292 	/* Send it out "upper" hook */
293 	NG_OUTBOUND_THREAD_REF();
294 	NG_SEND_DATA_ONLY(error, priv->upper, *mp);
295 	NG_OUTBOUND_THREAD_UNREF();
296 	return (error);
297 }
298 
299 /*
300  * A new Ethernet interface has been attached.
301  * Create a new node for it, etc.
302  */
303 static void
304 ng_ether_attach(struct ifnet *ifp)
305 {
306 	char name[IFNAMSIZ];
307 	priv_p priv;
308 	node_p node;
309 
310 	/*
311 	 * Do not create / attach an ether node to this ifnet if
312 	 * a netgraph node with the same name already exists.
313 	 * This should prevent ether nodes to become attached to
314 	 * eiface nodes, which may be problematic due to naming
315 	 * clashes.
316 	 */
317 	ng_ether_sanitize_ifname(ifp->if_xname, name);
318 	if ((node = ng_name2noderef(NULL, name)) != NULL) {
319 		NG_NODE_UNREF(node);
320 		return;
321 	}
322 
323 	/* Create node */
324 	KASSERT(!IFP2NG(ifp), ("%s: node already exists?", __func__));
325 	if (ng_make_node_common(&ng_ether_typestruct, &node) != 0) {
326 		log(LOG_ERR, "%s: can't %s for %s\n",
327 		    __func__, "create node", ifp->if_xname);
328 		return;
329 	}
330 
331 	/* Allocate private data */
332 	priv = malloc(sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
333 	if (priv == NULL) {
334 		log(LOG_ERR, "%s: can't %s for %s\n",
335 		    __func__, "allocate memory", ifp->if_xname);
336 		NG_NODE_UNREF(node);
337 		return;
338 	}
339 	NG_NODE_SET_PRIVATE(node, priv);
340 	priv->ifp = ifp;
341 	IFP2NG(ifp) = node;
342 	priv->hwassist = ifp->if_hwassist;
343 
344 	/* Try to give the node the same name as the interface */
345 	if (ng_name_node(node, name) != 0)
346 		log(LOG_WARNING, "%s: can't name node %s\n", __func__, name);
347 }
348 
349 /*
350  * An Ethernet interface is being detached.
351  * REALLY Destroy its node.
352  */
353 static void
354 ng_ether_detach(struct ifnet *ifp)
355 {
356 	const node_p node = IFP2NG(ifp);
357 	const priv_p priv = NG_NODE_PRIVATE(node);
358 
359 	taskqueue_drain(taskqueue_swi, &ifp->if_linktask);
360 	NG_NODE_REALLY_DIE(node);	/* Force real removal of node */
361 	/*
362 	 * We can't assume the ifnet is still around when we run shutdown
363 	 * So zap it now. XXX We HOPE that anything running at this time
364 	 * handles it (as it should in the non netgraph case).
365 	 */
366 	IFP2NG(ifp) = NULL;
367 	priv->ifp = NULL;	/* XXX race if interrupted an output packet */
368 	ng_rmnode_self(node);		/* remove all netgraph parts */
369 }
370 
371 /*
372  * Notify graph about link event.
373  * if_link_state_change() has already checked that the state has changed.
374  */
375 static void
376 ng_ether_link_state(struct ifnet *ifp, int state)
377 {
378 	const node_p node = IFP2NG(ifp);
379 	const priv_p priv = NG_NODE_PRIVATE(node);
380 	struct ng_mesg *msg;
381 	int cmd, dummy_error = 0;
382 
383 	if (state == LINK_STATE_UP)
384 		cmd = NGM_LINK_IS_UP;
385 	else if (state == LINK_STATE_DOWN)
386 		cmd = NGM_LINK_IS_DOWN;
387 	else
388 		return;
389 
390 	if (priv->lower != NULL) {
391 		NG_MKMESSAGE(msg, NGM_FLOW_COOKIE, cmd, 0, M_NOWAIT);
392 		if (msg != NULL)
393 			NG_SEND_MSG_HOOK(dummy_error, node, msg, priv->lower, 0);
394 	}
395 	if (priv->orphan != NULL) {
396 		NG_MKMESSAGE(msg, NGM_FLOW_COOKIE, cmd, 0, M_NOWAIT);
397 		if (msg != NULL)
398 			NG_SEND_MSG_HOOK(dummy_error, node, msg, priv->orphan, 0);
399 	}
400 }
401 
402 /*
403  * Interface arrival notification handler.
404  * The notification is produced in two cases:
405  *  o a new interface arrives
406  *  o an existing interface got renamed
407  * Currently the first case is handled by ng_ether_attach via special
408  * hook ng_ether_attach_p.
409  */
410 static void
411 ng_ether_ifnet_arrival_event(void *arg __unused, struct ifnet *ifp)
412 {
413 	char name[IFNAMSIZ];
414 	node_p node;
415 
416 	/* Only ethernet interfaces are of interest. */
417 	if (ifp->if_type != IFT_ETHER
418 	    && ifp->if_type != IFT_L2VLAN)
419 		return;
420 
421 	/*
422 	 * Just return if it's a new interface without an ng_ether companion.
423 	 */
424 	node = IFP2NG(ifp);
425 	if (node == NULL)
426 		return;
427 
428 	/* Try to give the node the same name as the new interface name */
429 	ng_ether_sanitize_ifname(ifp->if_xname, name);
430 	if (ng_name_node(node, name) != 0)
431 		log(LOG_WARNING, "%s: can't re-name node %s\n", __func__, name);
432 }
433 
434 /******************************************************************
435 		    NETGRAPH NODE METHODS
436 ******************************************************************/
437 
438 /*
439  * It is not possible or allowable to create a node of this type.
440  * Nodes get created when the interface is attached (or, when
441  * this node type's KLD is loaded).
442  */
443 static int
444 ng_ether_constructor(node_p node)
445 {
446 	return (EINVAL);
447 }
448 
449 /*
450  * Check for attaching a new hook.
451  */
452 static	int
453 ng_ether_newhook(node_p node, hook_p hook, const char *name)
454 {
455 	const priv_p priv = NG_NODE_PRIVATE(node);
456 	hook_p *hookptr;
457 
458 	/* Divert hook is an alias for lower */
459 	if (strcmp(name, NG_ETHER_HOOK_DIVERT) == 0)
460 		name = NG_ETHER_HOOK_LOWER;
461 
462 	/* Which hook? */
463 	if (strcmp(name, NG_ETHER_HOOK_UPPER) == 0) {
464 		hookptr = &priv->upper;
465 		NG_HOOK_SET_RCVDATA(hook, ng_ether_rcv_upper);
466 		NG_HOOK_SET_TO_INBOUND(hook);
467 	} else if (strcmp(name, NG_ETHER_HOOK_LOWER) == 0) {
468 		hookptr = &priv->lower;
469 		NG_HOOK_SET_RCVDATA(hook, ng_ether_rcv_lower);
470 	} else if (strcmp(name, NG_ETHER_HOOK_ORPHAN) == 0) {
471 		hookptr = &priv->orphan;
472 		NG_HOOK_SET_RCVDATA(hook, ng_ether_rcv_lower);
473 	} else
474 		return (EINVAL);
475 
476 	/* Check if already connected (shouldn't be, but doesn't hurt) */
477 	if (*hookptr != NULL)
478 		return (EISCONN);
479 
480 	/* Disable hardware checksums while 'upper' hook is connected */
481 	if (hookptr == &priv->upper)
482 		priv->ifp->if_hwassist = 0;
483 	NG_HOOK_HI_STACK(hook);
484 	/* OK */
485 	*hookptr = hook;
486 	return (0);
487 }
488 
489 /*
490  * Receive an incoming control message.
491  */
492 static int
493 ng_ether_rcvmsg(node_p node, item_p item, hook_p lasthook)
494 {
495 	const priv_p priv = NG_NODE_PRIVATE(node);
496 	struct ng_mesg *resp = NULL;
497 	int error = 0;
498 	struct ng_mesg *msg;
499 
500 	NGI_GET_MSG(item, msg);
501 	switch (msg->header.typecookie) {
502 	case NGM_ETHER_COOKIE:
503 		switch (msg->header.cmd) {
504 		case NGM_ETHER_GET_IFNAME:
505 			NG_MKRESPONSE(resp, msg, IFNAMSIZ, M_NOWAIT);
506 			if (resp == NULL) {
507 				error = ENOMEM;
508 				break;
509 			}
510 			strlcpy(resp->data, priv->ifp->if_xname, IFNAMSIZ);
511 			break;
512 		case NGM_ETHER_GET_IFINDEX:
513 			NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
514 			if (resp == NULL) {
515 				error = ENOMEM;
516 				break;
517 			}
518 			*((u_int32_t *)resp->data) = priv->ifp->if_index;
519 			break;
520 		case NGM_ETHER_GET_ENADDR:
521 			NG_MKRESPONSE(resp, msg, ETHER_ADDR_LEN, M_NOWAIT);
522 			if (resp == NULL) {
523 				error = ENOMEM;
524 				break;
525 			}
526 			bcopy(IF_LLADDR(priv->ifp),
527 			    resp->data, ETHER_ADDR_LEN);
528 			break;
529 		case NGM_ETHER_SET_ENADDR:
530 		    {
531 			if (msg->header.arglen != ETHER_ADDR_LEN) {
532 				error = EINVAL;
533 				break;
534 			}
535 			error = if_setlladdr(priv->ifp,
536 			    (u_char *)msg->data, ETHER_ADDR_LEN);
537 			break;
538 		    }
539 		case NGM_ETHER_GET_PROMISC:
540 			NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
541 			if (resp == NULL) {
542 				error = ENOMEM;
543 				break;
544 			}
545 			*((u_int32_t *)resp->data) = priv->promisc;
546 			break;
547 		case NGM_ETHER_SET_PROMISC:
548 		    {
549 			u_char want;
550 
551 			if (msg->header.arglen != sizeof(u_int32_t)) {
552 				error = EINVAL;
553 				break;
554 			}
555 			want = !!*((u_int32_t *)msg->data);
556 			if (want ^ priv->promisc) {
557 				if ((error = ifpromisc(priv->ifp, want)) != 0)
558 					break;
559 				priv->promisc = want;
560 			}
561 			break;
562 		    }
563 		case NGM_ETHER_GET_AUTOSRC:
564 			NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
565 			if (resp == NULL) {
566 				error = ENOMEM;
567 				break;
568 			}
569 			*((u_int32_t *)resp->data) = priv->autoSrcAddr;
570 			break;
571 		case NGM_ETHER_SET_AUTOSRC:
572 			if (msg->header.arglen != sizeof(u_int32_t)) {
573 				error = EINVAL;
574 				break;
575 			}
576 			priv->autoSrcAddr = !!*((u_int32_t *)msg->data);
577 			break;
578 		case NGM_ETHER_ADD_MULTI:
579 		    {
580 			struct sockaddr_dl sa_dl;
581 			struct epoch_tracker et;
582 			struct ifmultiaddr *ifma;
583 
584 			if (msg->header.arglen != ETHER_ADDR_LEN) {
585 				error = EINVAL;
586 				break;
587 			}
588 			bzero(&sa_dl, sizeof(struct sockaddr_dl));
589 			sa_dl.sdl_len = sizeof(struct sockaddr_dl);
590 			sa_dl.sdl_family = AF_LINK;
591 			sa_dl.sdl_alen = ETHER_ADDR_LEN;
592 			bcopy((void *)msg->data, LLADDR(&sa_dl),
593 			    ETHER_ADDR_LEN);
594 			/*
595 			 * Netgraph is only permitted to join groups once
596 			 * via the if_addmulti() KPI, because it cannot hold
597 			 * struct ifmultiaddr * between calls. It may also
598 			 * lose a race while we check if the membership
599 			 * already exists.
600 			 */
601 			NET_EPOCH_ENTER(et);
602 			ifma = if_findmulti(priv->ifp,
603 			    (struct sockaddr *)&sa_dl);
604 			NET_EPOCH_EXIT(et);
605 			if (ifma != NULL) {
606 				error = EADDRINUSE;
607 			} else {
608 				error = if_addmulti(priv->ifp,
609 				    (struct sockaddr *)&sa_dl, &ifma);
610 			}
611 			break;
612 		    }
613 		case NGM_ETHER_DEL_MULTI:
614 		    {
615 			struct sockaddr_dl sa_dl;
616 
617 			if (msg->header.arglen != ETHER_ADDR_LEN) {
618 				error = EINVAL;
619 				break;
620 			}
621 			bzero(&sa_dl, sizeof(struct sockaddr_dl));
622 			sa_dl.sdl_len = sizeof(struct sockaddr_dl);
623 			sa_dl.sdl_family = AF_LINK;
624 			sa_dl.sdl_alen = ETHER_ADDR_LEN;
625 			bcopy((void *)msg->data, LLADDR(&sa_dl),
626 			    ETHER_ADDR_LEN);
627 			error = if_delmulti(priv->ifp,
628 			    (struct sockaddr *)&sa_dl);
629 			break;
630 		    }
631 		case NGM_ETHER_DETACH:
632 			ng_ether_detach(priv->ifp);
633 			break;
634 		default:
635 			error = EINVAL;
636 			break;
637 		}
638 		break;
639 	default:
640 		error = EINVAL;
641 		break;
642 	}
643 	NG_RESPOND_MSG(error, node, item, resp);
644 	NG_FREE_MSG(msg);
645 	return (error);
646 }
647 
648 /*
649  * Receive data on a hook.
650  * Since we use per-hook recveive methods this should never be called.
651  */
652 static int
653 ng_ether_rcvdata(hook_p hook, item_p item)
654 {
655 	NG_FREE_ITEM(item);
656 
657 	panic("%s: weird hook", __func__);
658 }
659 
660 /*
661  * Handle an mbuf received on the "lower" or "orphan" hook.
662  */
663 static int
664 ng_ether_rcv_lower(hook_p hook, item_p item)
665 {
666 	struct mbuf *m;
667 	const node_p node = NG_HOOK_NODE(hook);
668 	const priv_p priv = NG_NODE_PRIVATE(node);
669  	struct ifnet *const ifp = priv->ifp;
670 
671 	NGI_GET_M(item, m);
672 	NG_FREE_ITEM(item);
673 
674 	/* Check whether interface is ready for packets */
675 
676 	if (!((ifp->if_flags & IFF_UP) &&
677 	    (ifp->if_drv_flags & IFF_DRV_RUNNING))) {
678 		NG_FREE_M(m);
679 		return (ENETDOWN);
680 	}
681 
682 	/* Make sure header is fully pulled up */
683 	if (m->m_pkthdr.len < sizeof(struct ether_header)) {
684 		NG_FREE_M(m);
685 		return (EINVAL);
686 	}
687 	if (m->m_len < sizeof(struct ether_header)
688 	    && (m = m_pullup(m, sizeof(struct ether_header))) == NULL)
689 		return (ENOBUFS);
690 
691 	/* Drop in the MAC address if desired */
692 	if (priv->autoSrcAddr) {
693 
694 		/* Make the mbuf writable if it's not already */
695 		if (!M_WRITABLE(m)
696 		    && (m = m_pullup(m, sizeof(struct ether_header))) == NULL)
697 			return (ENOBUFS);
698 
699 		/* Overwrite source MAC address */
700 		bcopy(IF_LLADDR(ifp),
701 		    mtod(m, struct ether_header *)->ether_shost,
702 		    ETHER_ADDR_LEN);
703 	}
704 
705 	/* Send it on its way */
706 	return ether_output_frame(ifp, m);
707 }
708 
709 /*
710  * Handle an mbuf received on the "upper" hook.
711  */
712 static int
713 ng_ether_rcv_upper(hook_p hook, item_p item)
714 {
715 	struct epoch_tracker et;
716 	struct mbuf *m;
717 	const node_p node = NG_HOOK_NODE(hook);
718 	const priv_p priv = NG_NODE_PRIVATE(node);
719 	struct ifnet *ifp = priv->ifp;
720 
721 	NGI_GET_M(item, m);
722 	NG_FREE_ITEM(item);
723 
724 	/* Check length and pull off header */
725 	if (m->m_pkthdr.len < sizeof(struct ether_header)) {
726 		NG_FREE_M(m);
727 		return (EINVAL);
728 	}
729 	if (m->m_len < sizeof(struct ether_header) &&
730 	    (m = m_pullup(m, sizeof(struct ether_header))) == NULL)
731 		return (ENOBUFS);
732 
733 	m->m_pkthdr.rcvif = ifp;
734 
735 	/* Pass the packet to the bridge, it may come back to us */
736 	if (ifp->if_bridge) {
737 		BRIDGE_INPUT(ifp, m);
738 		if (m == NULL)
739 			return (0);
740 	}
741 
742 	/* Route packet back in */
743 	NET_EPOCH_ENTER(et);
744 	ether_demux(ifp, m);
745 	NET_EPOCH_EXIT(et);
746 	return (0);
747 }
748 
749 /*
750  * Shutdown node. This resets the node but does not remove it
751  * unless the REALLY_DIE flag is set.
752  */
753 static int
754 ng_ether_shutdown(node_p node)
755 {
756 	const priv_p priv = NG_NODE_PRIVATE(node);
757 
758 	if (node->nd_flags & NGF_REALLY_DIE) {
759 		/*
760 		 * WE came here because the ethernet card is being unloaded,
761 		 * so stop being persistent.
762 		 * Actually undo all the things we did on creation.
763 		 * Assume the ifp has already been freed.
764 		 */
765 		NG_NODE_SET_PRIVATE(node, NULL);
766 		free(priv, M_NETGRAPH);
767 		NG_NODE_UNREF(node);	/* free node itself */
768 		return (0);
769 	}
770 	if (priv->promisc) {		/* disable promiscuous mode */
771 		(void)ifpromisc(priv->ifp, 0);
772 		priv->promisc = 0;
773 	}
774 	NG_NODE_REVIVE(node);		/* Signal ng_rmnode we are persisant */
775 
776 	return (0);
777 }
778 
779 /*
780  * Hook disconnection.
781  */
782 static int
783 ng_ether_disconnect(hook_p hook)
784 {
785 	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
786 
787 	if (hook == priv->upper) {
788 		priv->upper = NULL;
789 		if (priv->ifp != NULL)		/* restore h/w csum */
790 			priv->ifp->if_hwassist = priv->hwassist;
791 	} else if (hook == priv->lower)
792 		priv->lower = NULL;
793 	else if (hook == priv->orphan)
794 		priv->orphan = NULL;
795 	else
796 		panic("%s: weird hook", __func__);
797 	if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
798 	&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
799 		ng_rmnode_self(NG_HOOK_NODE(hook));	/* reset node */
800 	return (0);
801 }
802 
803 /******************************************************************
804 		    	INITIALIZATION
805 ******************************************************************/
806 
807 /*
808  * Handle loading and unloading for this node type.
809  */
810 static int
811 ng_ether_mod_event(module_t mod, int event, void *data)
812 {
813 	int error = 0;
814 
815 	switch (event) {
816 	case MOD_LOAD:
817 
818 		/* Register function hooks */
819 		if (ng_ether_attach_p != NULL) {
820 			error = EEXIST;
821 			break;
822 		}
823 		ng_ether_attach_p = ng_ether_attach;
824 		ng_ether_detach_p = ng_ether_detach;
825 		ng_ether_output_p = ng_ether_output;
826 		ng_ether_input_p = ng_ether_input;
827 		ng_ether_input_orphan_p = ng_ether_input_orphan;
828 		ng_ether_link_state_p = ng_ether_link_state;
829 
830 		ng_ether_ifnet_arrival_cookie =
831 		    EVENTHANDLER_REGISTER(ifnet_arrival_event,
832 		    ng_ether_ifnet_arrival_event, NULL, EVENTHANDLER_PRI_ANY);
833 		break;
834 
835 	case MOD_UNLOAD:
836 
837 		/*
838 		 * Note that the base code won't try to unload us until
839 		 * all nodes have been removed, and that can't happen
840 		 * until all Ethernet interfaces are removed. In any
841 		 * case, we know there are no nodes left if the action
842 		 * is MOD_UNLOAD, so there's no need to detach any nodes.
843 		 */
844 
845 		EVENTHANDLER_DEREGISTER(ifnet_arrival_event,
846 		    ng_ether_ifnet_arrival_cookie);
847 
848 		/* Unregister function hooks */
849 		ng_ether_attach_p = NULL;
850 		ng_ether_detach_p = NULL;
851 		ng_ether_output_p = NULL;
852 		ng_ether_input_p = NULL;
853 		ng_ether_input_orphan_p = NULL;
854 		ng_ether_link_state_p = NULL;
855 		break;
856 
857 	default:
858 		error = EOPNOTSUPP;
859 		break;
860 	}
861 	return (error);
862 }
863 
864 static void
865 vnet_ng_ether_init(const void *unused)
866 {
867 	struct ifnet *ifp;
868 
869 	/* If module load was rejected, don't attach to vnets. */
870 	if (ng_ether_attach_p != ng_ether_attach)
871 		return;
872 
873 	/* Create nodes for any already-existing Ethernet interfaces. */
874 	IFNET_RLOCK();
875 	CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) {
876 		if (ifp->if_type == IFT_ETHER
877 		    || ifp->if_type == IFT_L2VLAN)
878 			ng_ether_attach(ifp);
879 	}
880 	IFNET_RUNLOCK();
881 }
882 VNET_SYSINIT(vnet_ng_ether_init, SI_SUB_PSEUDO, SI_ORDER_ANY,
883     vnet_ng_ether_init, NULL);
884