xref: /freebsd/sys/netgraph/ng_ether.c (revision e32fecd0c2c3ee37c47ee100f169e7eb0282a873)
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/if_private.h>
67 #include <net/ethernet.h>
68 #include <net/if_bridgevar.h>
69 #include <net/vnet.h>
70 
71 #include <netgraph/ng_message.h>
72 #include <netgraph/netgraph.h>
73 #include <netgraph/ng_parse.h>
74 #include <netgraph/ng_ether.h>
75 
76 MODULE_VERSION(ng_ether, 1);
77 
78 #define IFP2NG(ifp)  ((ifp)->if_l2com)
79 
80 /* Per-node private data */
81 struct private {
82 	struct ifnet	*ifp;		/* associated interface */
83 	hook_p		upper;		/* upper hook connection */
84 	hook_p		lower;		/* lower hook connection */
85 	hook_p		orphan;		/* orphan hook connection */
86 	u_char		autoSrcAddr;	/* always overwrite source address */
87 	u_char		promisc;	/* promiscuous mode enabled */
88 	u_long		hwassist;	/* hardware checksum capabilities */
89 	u_int		flags;		/* flags e.g. really die */
90 };
91 typedef struct private *priv_p;
92 
93 /* Hook pointers used by if_ethersubr.c to callback to netgraph */
94 extern	void	(*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp);
95 extern	void	(*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m);
96 extern	int	(*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp);
97 extern	void	(*ng_ether_attach_p)(struct ifnet *ifp);
98 extern	void	(*ng_ether_detach_p)(struct ifnet *ifp);
99 extern	void	(*ng_ether_link_state_p)(struct ifnet *ifp, int state);
100 
101 /* Functional hooks called from if_ethersubr.c */
102 static void	ng_ether_input(struct ifnet *ifp, struct mbuf **mp);
103 static void	ng_ether_input_orphan(struct ifnet *ifp, struct mbuf *m);
104 static int	ng_ether_output(struct ifnet *ifp, struct mbuf **mp);
105 static void	ng_ether_attach(struct ifnet *ifp);
106 static void	ng_ether_detach(struct ifnet *ifp);
107 static void	ng_ether_link_state(struct ifnet *ifp, int state);
108 
109 /* Other functions */
110 static int	ng_ether_rcv_lower(hook_p node, item_p item);
111 static int	ng_ether_rcv_upper(hook_p node, item_p item);
112 
113 /* Netgraph node methods */
114 static ng_constructor_t	ng_ether_constructor;
115 static ng_rcvmsg_t	ng_ether_rcvmsg;
116 static ng_shutdown_t	ng_ether_shutdown;
117 static ng_newhook_t	ng_ether_newhook;
118 static ng_rcvdata_t	ng_ether_rcvdata;
119 static ng_disconnect_t	ng_ether_disconnect;
120 static int		ng_ether_mod_event(module_t mod, int event, void *data);
121 
122 static eventhandler_tag	ng_ether_ifnet_arrival_cookie;
123 
124 /* List of commands and how to convert arguments to/from ASCII */
125 static const struct ng_cmdlist ng_ether_cmdlist[] = {
126 	{
127 	  NGM_ETHER_COOKIE,
128 	  NGM_ETHER_GET_IFNAME,
129 	  "getifname",
130 	  NULL,
131 	  &ng_parse_string_type
132 	},
133 	{
134 	  NGM_ETHER_COOKIE,
135 	  NGM_ETHER_GET_IFINDEX,
136 	  "getifindex",
137 	  NULL,
138 	  &ng_parse_int32_type
139 	},
140 	{
141 	  NGM_ETHER_COOKIE,
142 	  NGM_ETHER_GET_ENADDR,
143 	  "getenaddr",
144 	  NULL,
145 	  &ng_parse_enaddr_type
146 	},
147 	{
148 	  NGM_ETHER_COOKIE,
149 	  NGM_ETHER_SET_ENADDR,
150 	  "setenaddr",
151 	  &ng_parse_enaddr_type,
152 	  NULL
153 	},
154 	{
155 	  NGM_ETHER_COOKIE,
156 	  NGM_ETHER_GET_PROMISC,
157 	  "getpromisc",
158 	  NULL,
159 	  &ng_parse_int32_type
160 	},
161 	{
162 	  NGM_ETHER_COOKIE,
163 	  NGM_ETHER_SET_PROMISC,
164 	  "setpromisc",
165 	  &ng_parse_int32_type,
166 	  NULL
167 	},
168 	{
169 	  NGM_ETHER_COOKIE,
170 	  NGM_ETHER_GET_AUTOSRC,
171 	  "getautosrc",
172 	  NULL,
173 	  &ng_parse_int32_type
174 	},
175 	{
176 	  NGM_ETHER_COOKIE,
177 	  NGM_ETHER_SET_AUTOSRC,
178 	  "setautosrc",
179 	  &ng_parse_int32_type,
180 	  NULL
181 	},
182 	{
183 	  NGM_ETHER_COOKIE,
184 	  NGM_ETHER_ADD_MULTI,
185 	  "addmulti",
186 	  &ng_parse_enaddr_type,
187 	  NULL
188 	},
189 	{
190 	  NGM_ETHER_COOKIE,
191 	  NGM_ETHER_DEL_MULTI,
192 	  "delmulti",
193 	  &ng_parse_enaddr_type,
194 	  NULL
195 	},
196 	{
197 	  NGM_ETHER_COOKIE,
198 	  NGM_ETHER_DETACH,
199 	  "detach",
200 	  NULL,
201 	  NULL
202 	},
203 	{ 0 }
204 };
205 
206 static struct ng_type ng_ether_typestruct = {
207 	.version =	NG_ABI_VERSION,
208 	.name =		NG_ETHER_NODE_TYPE,
209 	.mod_event =	ng_ether_mod_event,
210 	.constructor =	ng_ether_constructor,
211 	.rcvmsg =	ng_ether_rcvmsg,
212 	.shutdown =	ng_ether_shutdown,
213 	.newhook =	ng_ether_newhook,
214 	.rcvdata =	ng_ether_rcvdata,
215 	.disconnect =	ng_ether_disconnect,
216 	.cmdlist =	ng_ether_cmdlist,
217 };
218 NETGRAPH_INIT(ether, &ng_ether_typestruct);
219 
220 /******************************************************************
221 		    UTILITY FUNCTIONS
222 ******************************************************************/
223 static void
224 ng_ether_sanitize_ifname(const char *ifname, char *name)
225 {
226 	int i;
227 
228 	for (i = 0; i < IFNAMSIZ; i++) {
229 		if (ifname[i] == '.' || ifname[i] == ':')
230 			name[i] = '_';
231 		else
232 			name[i] = ifname[i];
233 		if (name[i] == '\0')
234 			break;
235 	}
236 }
237 
238 /******************************************************************
239 		    ETHERNET FUNCTION HOOKS
240 ******************************************************************/
241 
242 /*
243  * Handle a packet that has come in on an interface. We get to
244  * look at it here before any upper layer protocols do.
245  */
246 static void
247 ng_ether_input(struct ifnet *ifp, struct mbuf **mp)
248 {
249 	const node_p node = IFP2NG(ifp);
250 	const priv_p priv = NG_NODE_PRIVATE(node);
251 	int error;
252 
253 	/* If "lower" hook not connected, let packet continue */
254 	if (priv->lower == NULL)
255 		return;
256 	NG_SEND_DATA_ONLY(error, priv->lower, *mp);	/* sets *mp = NULL */
257 }
258 
259 /*
260  * Handle a packet that has come in on an interface, and which
261  * does not match any of our known protocols (an ``orphan'').
262  */
263 static void
264 ng_ether_input_orphan(struct ifnet *ifp, struct mbuf *m)
265 {
266 	const node_p node = IFP2NG(ifp);
267 	const priv_p priv = NG_NODE_PRIVATE(node);
268 	int error;
269 
270 	/* If "orphan" hook not connected, discard packet */
271 	if (priv->orphan == NULL) {
272 		m_freem(m);
273 		return;
274 	}
275 	NG_SEND_DATA_ONLY(error, priv->orphan, m);
276 }
277 
278 /*
279  * Handle a packet that is going out on an interface.
280  * The Ethernet header is already attached to the mbuf.
281  */
282 static int
283 ng_ether_output(struct ifnet *ifp, struct mbuf **mp)
284 {
285 	const node_p node = IFP2NG(ifp);
286 	const priv_p priv = NG_NODE_PRIVATE(node);
287 	int error = 0;
288 
289 	/* If "upper" hook not connected, let packet continue */
290 	if (priv->upper == NULL)
291 		return (0);
292 
293 	/* Send it out "upper" hook */
294 	NG_OUTBOUND_THREAD_REF();
295 	NG_SEND_DATA_ONLY(error, priv->upper, *mp);
296 	NG_OUTBOUND_THREAD_UNREF();
297 	return (error);
298 }
299 
300 /*
301  * A new Ethernet interface has been attached.
302  * Create a new node for it, etc.
303  */
304 static void
305 ng_ether_attach(struct ifnet *ifp)
306 {
307 	char name[IFNAMSIZ];
308 	priv_p priv;
309 	node_p node;
310 
311 	/*
312 	 * Do not create / attach an ether node to this ifnet if
313 	 * a netgraph node with the same name already exists.
314 	 * This should prevent ether nodes to become attached to
315 	 * eiface nodes, which may be problematic due to naming
316 	 * clashes.
317 	 */
318 	ng_ether_sanitize_ifname(ifp->if_xname, name);
319 	if ((node = ng_name2noderef(NULL, name)) != NULL) {
320 		NG_NODE_UNREF(node);
321 		return;
322 	}
323 
324 	/* Create node */
325 	KASSERT(!IFP2NG(ifp), ("%s: node already exists?", __func__));
326 	if (ng_make_node_common(&ng_ether_typestruct, &node) != 0) {
327 		log(LOG_ERR, "%s: can't %s for %s\n",
328 		    __func__, "create node", ifp->if_xname);
329 		return;
330 	}
331 
332 	/* Allocate private data */
333 	priv = malloc(sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
334 	if (priv == NULL) {
335 		log(LOG_ERR, "%s: can't %s for %s\n",
336 		    __func__, "allocate memory", ifp->if_xname);
337 		NG_NODE_UNREF(node);
338 		return;
339 	}
340 	NG_NODE_SET_PRIVATE(node, priv);
341 	priv->ifp = ifp;
342 	IFP2NG(ifp) = node;
343 	priv->hwassist = ifp->if_hwassist;
344 
345 	/* Try to give the node the same name as the interface */
346 	if (ng_name_node(node, name) != 0)
347 		log(LOG_WARNING, "%s: can't name node %s\n", __func__, name);
348 }
349 
350 /*
351  * An Ethernet interface is being detached.
352  * REALLY Destroy its node.
353  */
354 static void
355 ng_ether_detach(struct ifnet *ifp)
356 {
357 	const node_p node = IFP2NG(ifp);
358 	const priv_p priv = NG_NODE_PRIVATE(node);
359 
360 	taskqueue_drain(taskqueue_swi, &ifp->if_linktask);
361 	NG_NODE_REALLY_DIE(node);	/* Force real removal of node */
362 	/*
363 	 * We can't assume the ifnet is still around when we run shutdown
364 	 * So zap it now. XXX We HOPE that anything running at this time
365 	 * handles it (as it should in the non netgraph case).
366 	 */
367 	IFP2NG(ifp) = NULL;
368 	priv->ifp = NULL;	/* XXX race if interrupted an output packet */
369 	ng_rmnode_self(node);		/* remove all netgraph parts */
370 }
371 
372 /*
373  * Notify graph about link event.
374  * if_link_state_change() has already checked that the state has changed.
375  */
376 static void
377 ng_ether_link_state(struct ifnet *ifp, int state)
378 {
379 	const node_p node = IFP2NG(ifp);
380 	const priv_p priv = NG_NODE_PRIVATE(node);
381 	struct ng_mesg *msg;
382 	int cmd, dummy_error = 0;
383 
384 	if (state == LINK_STATE_UP)
385 		cmd = NGM_LINK_IS_UP;
386 	else if (state == LINK_STATE_DOWN)
387 		cmd = NGM_LINK_IS_DOWN;
388 	else
389 		return;
390 
391 	if (priv->lower != NULL) {
392 		NG_MKMESSAGE(msg, NGM_FLOW_COOKIE, cmd, 0, M_NOWAIT);
393 		if (msg != NULL)
394 			NG_SEND_MSG_HOOK(dummy_error, node, msg, priv->lower, 0);
395 	}
396 	if (priv->orphan != NULL) {
397 		NG_MKMESSAGE(msg, NGM_FLOW_COOKIE, cmd, 0, M_NOWAIT);
398 		if (msg != NULL)
399 			NG_SEND_MSG_HOOK(dummy_error, node, msg, priv->orphan, 0);
400 	}
401 }
402 
403 /*
404  * Interface arrival notification handler.
405  * The notification is produced in two cases:
406  *  o a new interface arrives
407  *  o an existing interface got renamed
408  * Currently the first case is handled by ng_ether_attach via special
409  * hook ng_ether_attach_p.
410  */
411 static void
412 ng_ether_ifnet_arrival_event(void *arg __unused, struct ifnet *ifp)
413 {
414 	char name[IFNAMSIZ];
415 	node_p node;
416 
417 	/* Only ethernet interfaces are of interest. */
418 	if (ifp->if_type != IFT_ETHER &&
419 	    ifp->if_type != IFT_L2VLAN &&
420 	    ifp->if_type != IFT_BRIDGE)
421 		return;
422 
423 	/*
424 	 * Just return if it's a new interface without an ng_ether companion.
425 	 */
426 	node = IFP2NG(ifp);
427 	if (node == NULL)
428 		return;
429 
430 	/* Try to give the node the same name as the new interface name */
431 	ng_ether_sanitize_ifname(ifp->if_xname, name);
432 	if (ng_name_node(node, name) != 0)
433 		log(LOG_WARNING, "%s: can't re-name node %s\n", __func__, name);
434 }
435 
436 /******************************************************************
437 		    NETGRAPH NODE METHODS
438 ******************************************************************/
439 
440 /*
441  * It is not possible or allowable to create a node of this type.
442  * Nodes get created when the interface is attached (or, when
443  * this node type's KLD is loaded).
444  */
445 static int
446 ng_ether_constructor(node_p node)
447 {
448 	return (EINVAL);
449 }
450 
451 /*
452  * Check for attaching a new hook.
453  */
454 static	int
455 ng_ether_newhook(node_p node, hook_p hook, const char *name)
456 {
457 	const priv_p priv = NG_NODE_PRIVATE(node);
458 	hook_p *hookptr;
459 
460 	/* Divert hook is an alias for lower */
461 	if (strcmp(name, NG_ETHER_HOOK_DIVERT) == 0)
462 		name = NG_ETHER_HOOK_LOWER;
463 
464 	/* Which hook? */
465 	if (strcmp(name, NG_ETHER_HOOK_UPPER) == 0) {
466 		hookptr = &priv->upper;
467 		NG_HOOK_SET_RCVDATA(hook, ng_ether_rcv_upper);
468 		NG_HOOK_SET_TO_INBOUND(hook);
469 	} else if (strcmp(name, NG_ETHER_HOOK_LOWER) == 0) {
470 		hookptr = &priv->lower;
471 		NG_HOOK_SET_RCVDATA(hook, ng_ether_rcv_lower);
472 	} else if (strcmp(name, NG_ETHER_HOOK_ORPHAN) == 0) {
473 		hookptr = &priv->orphan;
474 		NG_HOOK_SET_RCVDATA(hook, ng_ether_rcv_lower);
475 	} else
476 		return (EINVAL);
477 
478 	/* Check if already connected (shouldn't be, but doesn't hurt) */
479 	if (*hookptr != NULL)
480 		return (EISCONN);
481 
482 	/* Disable hardware checksums while 'upper' hook is connected */
483 	if (hookptr == &priv->upper)
484 		priv->ifp->if_hwassist = 0;
485 	NG_HOOK_HI_STACK(hook);
486 	/* OK */
487 	*hookptr = hook;
488 	return (0);
489 }
490 
491 /*
492  * Receive an incoming control message.
493  */
494 static int
495 ng_ether_rcvmsg(node_p node, item_p item, hook_p lasthook)
496 {
497 	const priv_p priv = NG_NODE_PRIVATE(node);
498 	struct ng_mesg *resp = NULL;
499 	int error = 0;
500 	struct ng_mesg *msg;
501 
502 	NGI_GET_MSG(item, msg);
503 	switch (msg->header.typecookie) {
504 	case NGM_ETHER_COOKIE:
505 		switch (msg->header.cmd) {
506 		case NGM_ETHER_GET_IFNAME:
507 			NG_MKRESPONSE(resp, msg, IFNAMSIZ, M_NOWAIT);
508 			if (resp == NULL) {
509 				error = ENOMEM;
510 				break;
511 			}
512 			strlcpy(resp->data, priv->ifp->if_xname, IFNAMSIZ);
513 			break;
514 		case NGM_ETHER_GET_IFINDEX:
515 			NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
516 			if (resp == NULL) {
517 				error = ENOMEM;
518 				break;
519 			}
520 			*((u_int32_t *)resp->data) = priv->ifp->if_index;
521 			break;
522 		case NGM_ETHER_GET_ENADDR:
523 			NG_MKRESPONSE(resp, msg, ETHER_ADDR_LEN, M_NOWAIT);
524 			if (resp == NULL) {
525 				error = ENOMEM;
526 				break;
527 			}
528 			bcopy(IF_LLADDR(priv->ifp),
529 			    resp->data, ETHER_ADDR_LEN);
530 			break;
531 		case NGM_ETHER_SET_ENADDR:
532 		    {
533 			if (msg->header.arglen != ETHER_ADDR_LEN) {
534 				error = EINVAL;
535 				break;
536 			}
537 			error = if_setlladdr(priv->ifp,
538 			    (u_char *)msg->data, ETHER_ADDR_LEN);
539 			break;
540 		    }
541 		case NGM_ETHER_GET_PROMISC:
542 			NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
543 			if (resp == NULL) {
544 				error = ENOMEM;
545 				break;
546 			}
547 			*((u_int32_t *)resp->data) = priv->promisc;
548 			break;
549 		case NGM_ETHER_SET_PROMISC:
550 		    {
551 			u_char want;
552 
553 			if (msg->header.arglen != sizeof(u_int32_t)) {
554 				error = EINVAL;
555 				break;
556 			}
557 			want = !!*((u_int32_t *)msg->data);
558 			if (want ^ priv->promisc) {
559 				if ((error = ifpromisc(priv->ifp, want)) != 0)
560 					break;
561 				priv->promisc = want;
562 			}
563 			break;
564 		    }
565 		case NGM_ETHER_GET_AUTOSRC:
566 			NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
567 			if (resp == NULL) {
568 				error = ENOMEM;
569 				break;
570 			}
571 			*((u_int32_t *)resp->data) = priv->autoSrcAddr;
572 			break;
573 		case NGM_ETHER_SET_AUTOSRC:
574 			if (msg->header.arglen != sizeof(u_int32_t)) {
575 				error = EINVAL;
576 				break;
577 			}
578 			priv->autoSrcAddr = !!*((u_int32_t *)msg->data);
579 			break;
580 		case NGM_ETHER_ADD_MULTI:
581 		    {
582 			struct sockaddr_dl sa_dl;
583 			struct epoch_tracker et;
584 			struct ifmultiaddr *ifma;
585 
586 			if (msg->header.arglen != ETHER_ADDR_LEN) {
587 				error = EINVAL;
588 				break;
589 			}
590 			bzero(&sa_dl, sizeof(struct sockaddr_dl));
591 			sa_dl.sdl_len = sizeof(struct sockaddr_dl);
592 			sa_dl.sdl_family = AF_LINK;
593 			sa_dl.sdl_alen = ETHER_ADDR_LEN;
594 			bcopy((void *)msg->data, LLADDR(&sa_dl),
595 			    ETHER_ADDR_LEN);
596 			/*
597 			 * Netgraph is only permitted to join groups once
598 			 * via the if_addmulti() KPI, because it cannot hold
599 			 * struct ifmultiaddr * between calls. It may also
600 			 * lose a race while we check if the membership
601 			 * already exists.
602 			 */
603 			NET_EPOCH_ENTER(et);
604 			ifma = if_findmulti(priv->ifp,
605 			    (struct sockaddr *)&sa_dl);
606 			NET_EPOCH_EXIT(et);
607 			if (ifma != NULL) {
608 				error = EADDRINUSE;
609 			} else {
610 				error = if_addmulti(priv->ifp,
611 				    (struct sockaddr *)&sa_dl, &ifma);
612 			}
613 			break;
614 		    }
615 		case NGM_ETHER_DEL_MULTI:
616 		    {
617 			struct sockaddr_dl sa_dl;
618 
619 			if (msg->header.arglen != ETHER_ADDR_LEN) {
620 				error = EINVAL;
621 				break;
622 			}
623 			bzero(&sa_dl, sizeof(struct sockaddr_dl));
624 			sa_dl.sdl_len = sizeof(struct sockaddr_dl);
625 			sa_dl.sdl_family = AF_LINK;
626 			sa_dl.sdl_alen = ETHER_ADDR_LEN;
627 			bcopy((void *)msg->data, LLADDR(&sa_dl),
628 			    ETHER_ADDR_LEN);
629 			error = if_delmulti(priv->ifp,
630 			    (struct sockaddr *)&sa_dl);
631 			break;
632 		    }
633 		case NGM_ETHER_DETACH:
634 			ng_ether_detach(priv->ifp);
635 			break;
636 		default:
637 			error = EINVAL;
638 			break;
639 		}
640 		break;
641 	default:
642 		error = EINVAL;
643 		break;
644 	}
645 	NG_RESPOND_MSG(error, node, item, resp);
646 	NG_FREE_MSG(msg);
647 	return (error);
648 }
649 
650 /*
651  * Receive data on a hook.
652  * Since we use per-hook recveive methods this should never be called.
653  */
654 static int
655 ng_ether_rcvdata(hook_p hook, item_p item)
656 {
657 	NG_FREE_ITEM(item);
658 
659 	panic("%s: weird hook", __func__);
660 }
661 
662 /*
663  * Handle an mbuf received on the "lower" or "orphan" hook.
664  */
665 static int
666 ng_ether_rcv_lower(hook_p hook, item_p item)
667 {
668 	struct mbuf *m;
669 	const node_p node = NG_HOOK_NODE(hook);
670 	const priv_p priv = NG_NODE_PRIVATE(node);
671  	struct ifnet *const ifp = priv->ifp;
672 
673 	NGI_GET_M(item, m);
674 	NG_FREE_ITEM(item);
675 
676 	/* Check whether interface is ready for packets */
677 
678 	if (!((ifp->if_flags & IFF_UP) &&
679 	    (ifp->if_drv_flags & IFF_DRV_RUNNING))) {
680 		NG_FREE_M(m);
681 		return (ENETDOWN);
682 	}
683 
684 	/* Make sure header is fully pulled up */
685 	if (m->m_pkthdr.len < sizeof(struct ether_header)) {
686 		NG_FREE_M(m);
687 		return (EINVAL);
688 	}
689 	if (m->m_len < sizeof(struct ether_header)
690 	    && (m = m_pullup(m, sizeof(struct ether_header))) == NULL)
691 		return (ENOBUFS);
692 
693 	/* Drop in the MAC address if desired */
694 	if (priv->autoSrcAddr) {
695 		/* Make the mbuf writable if it's not already */
696 		if (!M_WRITABLE(m)
697 		    && (m = m_pullup(m, sizeof(struct ether_header))) == NULL)
698 			return (ENOBUFS);
699 
700 		/* Overwrite source MAC address */
701 		bcopy(IF_LLADDR(ifp),
702 		    mtod(m, struct ether_header *)->ether_shost,
703 		    ETHER_ADDR_LEN);
704 	}
705 
706 	/* Send it on its way */
707 	return ether_output_frame(ifp, m);
708 }
709 
710 /*
711  * Handle an mbuf received on the "upper" hook.
712  */
713 static int
714 ng_ether_rcv_upper(hook_p hook, item_p item)
715 {
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 	ether_demux(ifp, m);
744 	return (0);
745 }
746 
747 /*
748  * Shutdown node. This resets the node but does not remove it
749  * unless the REALLY_DIE flag is set.
750  */
751 static int
752 ng_ether_shutdown(node_p node)
753 {
754 	const priv_p priv = NG_NODE_PRIVATE(node);
755 
756 	if (node->nd_flags & NGF_REALLY_DIE) {
757 		/*
758 		 * The ifnet is going away, perhaps because the driver was
759 		 * unloaded or its vnet is being torn down.
760 		 */
761 		NG_NODE_SET_PRIVATE(node, NULL);
762 		if (priv->ifp != NULL)
763 			IFP2NG(priv->ifp) = NULL;
764 		free(priv, M_NETGRAPH);
765 		NG_NODE_UNREF(node);	/* free node itself */
766 		return (0);
767 	}
768 	if (priv->promisc) {		/* disable promiscuous mode */
769 		(void)ifpromisc(priv->ifp, 0);
770 		priv->promisc = 0;
771 	}
772 	NG_NODE_REVIVE(node);		/* Signal ng_rmnode we are persisant */
773 
774 	return (0);
775 }
776 
777 /*
778  * Hook disconnection.
779  */
780 static int
781 ng_ether_disconnect(hook_p hook)
782 {
783 	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
784 
785 	if (hook == priv->upper) {
786 		priv->upper = NULL;
787 		if (priv->ifp != NULL)		/* restore h/w csum */
788 			priv->ifp->if_hwassist = priv->hwassist;
789 	} else if (hook == priv->lower)
790 		priv->lower = NULL;
791 	else if (hook == priv->orphan)
792 		priv->orphan = NULL;
793 	else
794 		panic("%s: weird hook", __func__);
795 	if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
796 	&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
797 		ng_rmnode_self(NG_HOOK_NODE(hook));	/* reset node */
798 	return (0);
799 }
800 
801 /******************************************************************
802 		    	INITIALIZATION
803 ******************************************************************/
804 
805 /*
806  * Handle loading and unloading for this node type.
807  */
808 static int
809 ng_ether_mod_event(module_t mod, int event, void *data)
810 {
811 	int error = 0;
812 
813 	switch (event) {
814 	case MOD_LOAD:
815 
816 		/* Register function hooks */
817 		if (ng_ether_attach_p != NULL) {
818 			error = EEXIST;
819 			break;
820 		}
821 		ng_ether_attach_p = ng_ether_attach;
822 		ng_ether_detach_p = ng_ether_detach;
823 		ng_ether_output_p = ng_ether_output;
824 		ng_ether_input_p = ng_ether_input;
825 		ng_ether_input_orphan_p = ng_ether_input_orphan;
826 		ng_ether_link_state_p = ng_ether_link_state;
827 
828 		ng_ether_ifnet_arrival_cookie =
829 		    EVENTHANDLER_REGISTER(ifnet_arrival_event,
830 		    ng_ether_ifnet_arrival_event, NULL, EVENTHANDLER_PRI_ANY);
831 		break;
832 
833 	case MOD_UNLOAD:
834 
835 		/*
836 		 * Note that the base code won't try to unload us until
837 		 * all nodes have been removed, and that can't happen
838 		 * until all Ethernet interfaces are removed. In any
839 		 * case, we know there are no nodes left if the action
840 		 * is MOD_UNLOAD, so there's no need to detach any nodes.
841 		 */
842 
843 		EVENTHANDLER_DEREGISTER(ifnet_arrival_event,
844 		    ng_ether_ifnet_arrival_cookie);
845 
846 		/* Unregister function hooks */
847 		ng_ether_attach_p = NULL;
848 		ng_ether_detach_p = NULL;
849 		ng_ether_output_p = NULL;
850 		ng_ether_input_p = NULL;
851 		ng_ether_input_orphan_p = NULL;
852 		ng_ether_link_state_p = NULL;
853 		break;
854 
855 	default:
856 		error = EOPNOTSUPP;
857 		break;
858 	}
859 	return (error);
860 }
861 
862 static void
863 vnet_ng_ether_init(const void *unused)
864 {
865 	struct ifnet *ifp;
866 
867 	/* If module load was rejected, don't attach to vnets. */
868 	if (ng_ether_attach_p != ng_ether_attach)
869 		return;
870 
871 	/* Create nodes for any already-existing Ethernet interfaces. */
872 	IFNET_RLOCK();
873 	CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) {
874 		if (ifp->if_type == IFT_ETHER ||
875 		    ifp->if_type == IFT_L2VLAN ||
876 		    ifp->if_type == IFT_BRIDGE)
877 			ng_ether_attach(ifp);
878 	}
879 	IFNET_RUNLOCK();
880 }
881 VNET_SYSINIT(vnet_ng_ether_init, SI_SUB_PSEUDO, SI_ORDER_ANY,
882     vnet_ng_ether_init, NULL);
883