xref: /freebsd/sys/netgraph/ng_ether.c (revision 54ebdd631db8c0bba2baab0155f603a8b5cf014a)
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 #include <sys/vimage.h>
58 
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 #include <net/if_bridgevar.h>
66 #include <net/vnet.h>
67 
68 #include <netgraph/ng_message.h>
69 #include <netgraph/netgraph.h>
70 #include <netgraph/ng_parse.h>
71 #include <netgraph/ng_ether.h>
72 
73 #define IFP2NG(ifp)  (IFP2AC((ifp))->ac_netgraph)
74 
75 /* Per-node private data */
76 struct private {
77 	struct ifnet	*ifp;		/* associated interface */
78 	hook_p		upper;		/* upper hook connection */
79 	hook_p		lower;		/* lower hook connection */
80 	hook_p		orphan;		/* orphan hook connection */
81 	u_char		autoSrcAddr;	/* always overwrite source address */
82 	u_char		promisc;	/* promiscuous mode enabled */
83 	u_long		hwassist;	/* hardware checksum capabilities */
84 	u_int		flags;		/* flags e.g. really die */
85 };
86 typedef struct private *priv_p;
87 
88 /* Hook pointers used by if_ethersubr.c to callback to netgraph */
89 extern	void	(*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp);
90 extern	void	(*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m);
91 extern	int	(*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp);
92 extern	void	(*ng_ether_attach_p)(struct ifnet *ifp);
93 extern	void	(*ng_ether_detach_p)(struct ifnet *ifp);
94 extern	void	(*ng_ether_link_state_p)(struct ifnet *ifp, int state);
95 
96 /* Functional hooks called from if_ethersubr.c */
97 static void	ng_ether_input(struct ifnet *ifp, struct mbuf **mp);
98 static void	ng_ether_input_orphan(struct ifnet *ifp, struct mbuf *m);
99 static int	ng_ether_output(struct ifnet *ifp, struct mbuf **mp);
100 static void	ng_ether_attach(struct ifnet *ifp);
101 static void	ng_ether_detach(struct ifnet *ifp);
102 static void	ng_ether_link_state(struct ifnet *ifp, int state);
103 
104 /* Other functions */
105 static int	ng_ether_rcv_lower(node_p node, struct mbuf *m);
106 static int	ng_ether_rcv_upper(node_p node, struct mbuf *m);
107 
108 /* Netgraph node methods */
109 static ng_constructor_t	ng_ether_constructor;
110 static ng_rcvmsg_t	ng_ether_rcvmsg;
111 static ng_shutdown_t	ng_ether_shutdown;
112 static ng_newhook_t	ng_ether_newhook;
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 	{
190 	  NGM_ETHER_COOKIE,
191 	  NGM_ETHER_DETACH,
192 	  "detach",
193 	  NULL,
194 	  NULL
195 	},
196 	{ 0 }
197 };
198 
199 static struct ng_type ng_ether_typestruct = {
200 	.version =	NG_ABI_VERSION,
201 	.name =		NG_ETHER_NODE_TYPE,
202 	.mod_event =	ng_ether_mod_event,
203 	.constructor =	ng_ether_constructor,
204 	.rcvmsg =	ng_ether_rcvmsg,
205 	.shutdown =	ng_ether_shutdown,
206 	.newhook =	ng_ether_newhook,
207 	.rcvdata =	ng_ether_rcvdata,
208 	.disconnect =	ng_ether_disconnect,
209 	.cmdlist =	ng_ether_cmdlist,
210 };
211 NETGRAPH_INIT(ether, &ng_ether_typestruct);
212 
213 /******************************************************************
214 		    ETHERNET FUNCTION HOOKS
215 ******************************************************************/
216 
217 /*
218  * Handle a packet that has come in on an interface. We get to
219  * look at it here before any upper layer protocols do.
220  *
221  * NOTE: this function will get called at splimp()
222  */
223 static void
224 ng_ether_input(struct ifnet *ifp, struct mbuf **mp)
225 {
226 	const node_p node = IFP2NG(ifp);
227 	const priv_p priv = NG_NODE_PRIVATE(node);
228 	int error;
229 
230 	/* If "lower" hook not connected, let packet continue */
231 	if (priv->lower == NULL)
232 		return;
233 	NG_SEND_DATA_ONLY(error, priv->lower, *mp);	/* sets *mp = NULL */
234 }
235 
236 /*
237  * Handle a packet that has come in on an interface, and which
238  * does not match any of our known protocols (an ``orphan'').
239  *
240  * NOTE: this function will get called at splimp()
241  */
242 static void
243 ng_ether_input_orphan(struct ifnet *ifp, struct mbuf *m)
244 {
245 	const node_p node = IFP2NG(ifp);
246 	const priv_p priv = NG_NODE_PRIVATE(node);
247 	int error;
248 
249 	/* If "orphan" hook not connected, discard packet */
250 	if (priv->orphan == NULL) {
251 		m_freem(m);
252 		return;
253 	}
254 	NG_SEND_DATA_ONLY(error, priv->orphan, m);
255 }
256 
257 /*
258  * Handle a packet that is going out on an interface.
259  * The Ethernet header is already attached to the mbuf.
260  */
261 static int
262 ng_ether_output(struct ifnet *ifp, struct mbuf **mp)
263 {
264 	const node_p node = IFP2NG(ifp);
265 	const priv_p priv = NG_NODE_PRIVATE(node);
266 	int error = 0;
267 
268 	/* If "upper" hook not connected, let packet continue */
269 	if (priv->upper == NULL)
270 		return (0);
271 
272 	/* Send it out "upper" hook */
273 	NG_SEND_DATA_ONLY(error, priv->upper, *mp);
274 	return (error);
275 }
276 
277 /*
278  * A new Ethernet interface has been attached.
279  * Create a new node for it, etc.
280  */
281 static void
282 ng_ether_attach(struct ifnet *ifp)
283 {
284 	priv_p priv;
285 	node_p node;
286 
287 	/* Create node */
288 	KASSERT(!IFP2NG(ifp), ("%s: node already exists?", __func__));
289 	if (ng_make_node_common(&ng_ether_typestruct, &node) != 0) {
290 		log(LOG_ERR, "%s: can't %s for %s\n",
291 		    __func__, "create node", ifp->if_xname);
292 		return;
293 	}
294 
295 	/* Allocate private data */
296 	priv = malloc(sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
297 	if (priv == NULL) {
298 		log(LOG_ERR, "%s: can't %s for %s\n",
299 		    __func__, "allocate memory", ifp->if_xname);
300 		NG_NODE_UNREF(node);
301 		return;
302 	}
303 	NG_NODE_SET_PRIVATE(node, priv);
304 	priv->ifp = ifp;
305 	IFP2NG(ifp) = node;
306 	priv->hwassist = ifp->if_hwassist;
307 
308 	/* Try to give the node the same name as the interface */
309 	if (ng_name_node(node, ifp->if_xname) != 0) {
310 		log(LOG_WARNING, "%s: can't name node %s\n",
311 		    __func__, ifp->if_xname);
312 	}
313 }
314 
315 /*
316  * An Ethernet interface is being detached.
317  * REALLY Destroy its node.
318  */
319 static void
320 ng_ether_detach(struct ifnet *ifp)
321 {
322 	const node_p node = IFP2NG(ifp);
323 	const priv_p priv = NG_NODE_PRIVATE(node);
324 
325 	NG_NODE_REALLY_DIE(node);	/* Force real removal of node */
326 	/*
327 	 * We can't assume the ifnet is still around when we run shutdown
328 	 * So zap it now. XXX We HOPE that anything running at this time
329 	 * handles it (as it should in the non netgraph case).
330 	 */
331 	IFP2NG(ifp) = NULL;
332 	priv->ifp = NULL;	/* XXX race if interrupted an output packet */
333 	ng_rmnode_self(node);		/* remove all netgraph parts */
334 }
335 
336 /*
337  * Notify graph about link event.
338  * if_link_state_change() has already checked that the state has changed.
339  */
340 static void
341 ng_ether_link_state(struct ifnet *ifp, int state)
342 {
343 	const node_p node = IFP2NG(ifp);
344 	const priv_p priv = NG_NODE_PRIVATE(node);
345 	struct ng_mesg *msg;
346 	int cmd, dummy_error = 0;
347 
348 	if (priv->lower == NULL)
349                 return;
350 
351 	if (state == LINK_STATE_UP)
352 		cmd = NGM_LINK_IS_UP;
353 	else if (state == LINK_STATE_DOWN)
354 		cmd = NGM_LINK_IS_DOWN;
355 	else
356 		return;
357 
358 	NG_MKMESSAGE(msg, NGM_FLOW_COOKIE, cmd, 0, M_NOWAIT);
359 	if (msg != NULL)
360 		NG_SEND_MSG_HOOK(dummy_error, node, msg, priv->lower, 0);
361 }
362 
363 /******************************************************************
364 		    NETGRAPH NODE METHODS
365 ******************************************************************/
366 
367 /*
368  * It is not possible or allowable to create a node of this type.
369  * Nodes get created when the interface is attached (or, when
370  * this node type's KLD is loaded).
371  */
372 static int
373 ng_ether_constructor(node_p node)
374 {
375 	return (EINVAL);
376 }
377 
378 /*
379  * Check for attaching a new hook.
380  */
381 static	int
382 ng_ether_newhook(node_p node, hook_p hook, const char *name)
383 {
384 	const priv_p priv = NG_NODE_PRIVATE(node);
385 	hook_p *hookptr;
386 
387 	/* Divert hook is an alias for lower */
388 	if (strcmp(name, NG_ETHER_HOOK_DIVERT) == 0)
389 		name = NG_ETHER_HOOK_LOWER;
390 
391 	/* Which hook? */
392 	if (strcmp(name, NG_ETHER_HOOK_UPPER) == 0)
393 		hookptr = &priv->upper;
394 	else if (strcmp(name, NG_ETHER_HOOK_LOWER) == 0)
395 		hookptr = &priv->lower;
396 	else if (strcmp(name, NG_ETHER_HOOK_ORPHAN) == 0)
397 		hookptr = &priv->orphan;
398 	else
399 		return (EINVAL);
400 
401 	/* Check if already connected (shouldn't be, but doesn't hurt) */
402 	if (*hookptr != NULL)
403 		return (EISCONN);
404 
405 	/* Disable hardware checksums while 'upper' hook is connected */
406 	if (hookptr == &priv->upper)
407 		priv->ifp->if_hwassist = 0;
408 
409 	/* OK */
410 	*hookptr = hook;
411 	return (0);
412 }
413 
414 /*
415  * Receive an incoming control message.
416  */
417 static int
418 ng_ether_rcvmsg(node_p node, item_p item, hook_p lasthook)
419 {
420 	const priv_p priv = NG_NODE_PRIVATE(node);
421 	struct ng_mesg *resp = NULL;
422 	int error = 0;
423 	struct ng_mesg *msg;
424 
425 	NGI_GET_MSG(item, msg);
426 	switch (msg->header.typecookie) {
427 	case NGM_ETHER_COOKIE:
428 		switch (msg->header.cmd) {
429 		case NGM_ETHER_GET_IFNAME:
430 			NG_MKRESPONSE(resp, msg, IFNAMSIZ, M_NOWAIT);
431 			if (resp == NULL) {
432 				error = ENOMEM;
433 				break;
434 			}
435 			strlcpy(resp->data, priv->ifp->if_xname, IFNAMSIZ);
436 			break;
437 		case NGM_ETHER_GET_IFINDEX:
438 			NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
439 			if (resp == NULL) {
440 				error = ENOMEM;
441 				break;
442 			}
443 			*((u_int32_t *)resp->data) = priv->ifp->if_index;
444 			break;
445 		case NGM_ETHER_GET_ENADDR:
446 			NG_MKRESPONSE(resp, msg, ETHER_ADDR_LEN, M_NOWAIT);
447 			if (resp == NULL) {
448 				error = ENOMEM;
449 				break;
450 			}
451 			bcopy(IF_LLADDR(priv->ifp),
452 			    resp->data, ETHER_ADDR_LEN);
453 			break;
454 		case NGM_ETHER_SET_ENADDR:
455 		    {
456 			if (msg->header.arglen != ETHER_ADDR_LEN) {
457 				error = EINVAL;
458 				break;
459 			}
460 			error = if_setlladdr(priv->ifp,
461 			    (u_char *)msg->data, ETHER_ADDR_LEN);
462 			break;
463 		    }
464 		case NGM_ETHER_GET_PROMISC:
465 			NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
466 			if (resp == NULL) {
467 				error = ENOMEM;
468 				break;
469 			}
470 			*((u_int32_t *)resp->data) = priv->promisc;
471 			break;
472 		case NGM_ETHER_SET_PROMISC:
473 		    {
474 			u_char want;
475 
476 			if (msg->header.arglen != sizeof(u_int32_t)) {
477 				error = EINVAL;
478 				break;
479 			}
480 			want = !!*((u_int32_t *)msg->data);
481 			if (want ^ priv->promisc) {
482 				if ((error = ifpromisc(priv->ifp, want)) != 0)
483 					break;
484 				priv->promisc = want;
485 			}
486 			break;
487 		    }
488 		case NGM_ETHER_GET_AUTOSRC:
489 			NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
490 			if (resp == NULL) {
491 				error = ENOMEM;
492 				break;
493 			}
494 			*((u_int32_t *)resp->data) = priv->autoSrcAddr;
495 			break;
496 		case NGM_ETHER_SET_AUTOSRC:
497 			if (msg->header.arglen != sizeof(u_int32_t)) {
498 				error = EINVAL;
499 				break;
500 			}
501 			priv->autoSrcAddr = !!*((u_int32_t *)msg->data);
502 			break;
503 		case NGM_ETHER_ADD_MULTI:
504 		    {
505 			struct sockaddr_dl sa_dl;
506 			struct ifmultiaddr *ifma;
507 
508 			if (msg->header.arglen != ETHER_ADDR_LEN) {
509 				error = EINVAL;
510 				break;
511 			}
512 			bzero(&sa_dl, sizeof(struct sockaddr_dl));
513 			sa_dl.sdl_len = sizeof(struct sockaddr_dl);
514 			sa_dl.sdl_family = AF_LINK;
515 			sa_dl.sdl_alen = ETHER_ADDR_LEN;
516 			bcopy((void *)msg->data, LLADDR(&sa_dl),
517 			    ETHER_ADDR_LEN);
518 			/*
519 			 * Netgraph is only permitted to join groups once
520 			 * via the if_addmulti() KPI, because it cannot hold
521 			 * struct ifmultiaddr * between calls. It may also
522 			 * lose a race while we check if the membership
523 			 * already exists.
524 			 */
525 			IF_ADDR_LOCK(priv->ifp);
526 			ifma = if_findmulti(priv->ifp,
527 			    (struct sockaddr *)&sa_dl);
528 			IF_ADDR_UNLOCK(priv->ifp);
529 			if (ifma != NULL) {
530 				error = EADDRINUSE;
531 			} else {
532 				error = if_addmulti(priv->ifp,
533 				    (struct sockaddr *)&sa_dl, &ifma);
534 			}
535 			break;
536 		    }
537 		case NGM_ETHER_DEL_MULTI:
538 		    {
539 			struct sockaddr_dl sa_dl;
540 
541 			if (msg->header.arglen != ETHER_ADDR_LEN) {
542 				error = EINVAL;
543 				break;
544 			}
545 			bzero(&sa_dl, sizeof(struct sockaddr_dl));
546 			sa_dl.sdl_len = sizeof(struct sockaddr_dl);
547 			sa_dl.sdl_family = AF_LINK;
548 			sa_dl.sdl_alen = ETHER_ADDR_LEN;
549 			bcopy((void *)msg->data, LLADDR(&sa_dl),
550 			    ETHER_ADDR_LEN);
551 			error = if_delmulti(priv->ifp,
552 			    (struct sockaddr *)&sa_dl);
553 			break;
554 		    }
555 		case NGM_ETHER_DETACH:
556 			ng_ether_detach(priv->ifp);
557 			break;
558 		default:
559 			error = EINVAL;
560 			break;
561 		}
562 		break;
563 	default:
564 		error = EINVAL;
565 		break;
566 	}
567 	NG_RESPOND_MSG(error, node, item, resp);
568 	NG_FREE_MSG(msg);
569 	return (error);
570 }
571 
572 /*
573  * Receive data on a hook.
574  */
575 static int
576 ng_ether_rcvdata(hook_p hook, item_p item)
577 {
578 	const node_p node = NG_HOOK_NODE(hook);
579 	const priv_p priv = NG_NODE_PRIVATE(node);
580 	struct mbuf *m;
581 
582 	NGI_GET_M(item, m);
583 	NG_FREE_ITEM(item);
584 
585 	if (hook == priv->lower || hook == priv->orphan)
586 		return ng_ether_rcv_lower(node, m);
587 	if (hook == priv->upper)
588 		return ng_ether_rcv_upper(node, m);
589 	panic("%s: weird hook", __func__);
590 #ifdef RESTARTABLE_PANICS /* so we don't get an error msg in LINT */
591 	return (0);
592 #endif
593 }
594 
595 /*
596  * Handle an mbuf received on the "lower" or "orphan" hook.
597  */
598 static int
599 ng_ether_rcv_lower(node_p node, struct mbuf *m)
600 {
601 	const priv_p priv = NG_NODE_PRIVATE(node);
602  	struct ifnet *const ifp = priv->ifp;
603 
604 	/* Check whether interface is ready for packets */
605 	if (!((ifp->if_flags & IFF_UP) &&
606 	    (ifp->if_drv_flags & IFF_DRV_RUNNING))) {
607 		NG_FREE_M(m);
608 		return (ENETDOWN);
609 	}
610 
611 	/* Make sure header is fully pulled up */
612 	if (m->m_pkthdr.len < sizeof(struct ether_header)) {
613 		NG_FREE_M(m);
614 		return (EINVAL);
615 	}
616 	if (m->m_len < sizeof(struct ether_header)
617 	    && (m = m_pullup(m, sizeof(struct ether_header))) == NULL)
618 		return (ENOBUFS);
619 
620 	/* Drop in the MAC address if desired */
621 	if (priv->autoSrcAddr) {
622 
623 		/* Make the mbuf writable if it's not already */
624 		if (!M_WRITABLE(m)
625 		    && (m = m_pullup(m, sizeof(struct ether_header))) == NULL)
626 			return (ENOBUFS);
627 
628 		/* Overwrite source MAC address */
629 		bcopy(IF_LLADDR(ifp),
630 		    mtod(m, struct ether_header *)->ether_shost,
631 		    ETHER_ADDR_LEN);
632 	}
633 
634 	/* Send it on its way */
635 	return ether_output_frame(ifp, m);
636 }
637 
638 /*
639  * Handle an mbuf received on the "upper" hook.
640  */
641 static int
642 ng_ether_rcv_upper(node_p node, struct mbuf *m)
643 {
644 	const priv_p priv = NG_NODE_PRIVATE(node);
645 	struct ifnet *ifp = priv->ifp;
646 
647 	/* Check length and pull off header */
648 	if (m->m_pkthdr.len < sizeof(struct ether_header)) {
649 		NG_FREE_M(m);
650 		return (EINVAL);
651 	}
652 	if (m->m_len < sizeof(struct ether_header) &&
653 	    (m = m_pullup(m, sizeof(struct ether_header))) == NULL)
654 		return (ENOBUFS);
655 
656 	m->m_pkthdr.rcvif = ifp;
657 
658 	/* Pass the packet to the bridge, it may come back to us */
659 	if (ifp->if_bridge) {
660 		BRIDGE_INPUT(ifp, m);
661 		if (m == NULL)
662 			return (0);
663 	}
664 
665 	/* Route packet back in */
666 	ether_demux(ifp, m);
667 	return (0);
668 }
669 
670 /*
671  * Shutdown node. This resets the node but does not remove it
672  * unless the REALLY_DIE flag is set.
673  */
674 static int
675 ng_ether_shutdown(node_p node)
676 {
677 	const priv_p priv = NG_NODE_PRIVATE(node);
678 
679 	if (node->nd_flags & NGF_REALLY_DIE) {
680 		/*
681 		 * WE came here because the ethernet card is being unloaded,
682 		 * so stop being persistant.
683 		 * Actually undo all the things we did on creation.
684 		 * Assume the ifp has already been freed.
685 		 */
686 		NG_NODE_SET_PRIVATE(node, NULL);
687 		free(priv, M_NETGRAPH);
688 		NG_NODE_UNREF(node);	/* free node itself */
689 		return (0);
690 	}
691 	if (priv->promisc) {		/* disable promiscuous mode */
692 		(void)ifpromisc(priv->ifp, 0);
693 		priv->promisc = 0;
694 	}
695 	priv->autoSrcAddr = 1;		/* reset auto-src-addr flag */
696 	NG_NODE_REVIVE(node);		/* Signal ng_rmnode we are persisant */
697 
698 	return (0);
699 }
700 
701 /*
702  * Hook disconnection.
703  */
704 static int
705 ng_ether_disconnect(hook_p hook)
706 {
707 	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
708 
709 	if (hook == priv->upper) {
710 		priv->upper = NULL;
711 		if (priv->ifp != NULL)		/* restore h/w csum */
712 			priv->ifp->if_hwassist = priv->hwassist;
713 	} else if (hook == priv->lower)
714 		priv->lower = NULL;
715 	else if (hook == priv->orphan)
716 		priv->orphan = NULL;
717 	else
718 		panic("%s: weird hook", __func__);
719 	if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
720 	&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
721 		ng_rmnode_self(NG_HOOK_NODE(hook));	/* reset node */
722 	return (0);
723 }
724 
725 /******************************************************************
726 		    	INITIALIZATION
727 ******************************************************************/
728 
729 /*
730  * Handle loading and unloading for this node type.
731  */
732 static int
733 ng_ether_mod_event(module_t mod, int event, void *data)
734 {
735 	struct ifnet *ifp;
736 	int error = 0;
737 	int s;
738 
739 	s = splnet();
740 	switch (event) {
741 	case MOD_LOAD:
742 
743 		/* Register function hooks */
744 		if (ng_ether_attach_p != NULL) {
745 			error = EEXIST;
746 			break;
747 		}
748 		ng_ether_attach_p = ng_ether_attach;
749 		ng_ether_detach_p = ng_ether_detach;
750 		ng_ether_output_p = ng_ether_output;
751 		ng_ether_input_p = ng_ether_input;
752 		ng_ether_input_orphan_p = ng_ether_input_orphan;
753 		ng_ether_link_state_p = ng_ether_link_state;
754 
755 		/* Create nodes for any already-existing Ethernet interfaces */
756 		IFNET_RLOCK();
757 		TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
758 			if (ifp->if_type == IFT_ETHER
759 			    || ifp->if_type == IFT_L2VLAN)
760 				ng_ether_attach(ifp);
761 		}
762 		IFNET_RUNLOCK();
763 		break;
764 
765 	case MOD_UNLOAD:
766 
767 		/*
768 		 * Note that the base code won't try to unload us until
769 		 * all nodes have been removed, and that can't happen
770 		 * until all Ethernet interfaces are removed. In any
771 		 * case, we know there are no nodes left if the action
772 		 * is MOD_UNLOAD, so there's no need to detach any nodes.
773 		 */
774 
775 		/* Unregister function hooks */
776 		ng_ether_attach_p = NULL;
777 		ng_ether_detach_p = NULL;
778 		ng_ether_output_p = NULL;
779 		ng_ether_input_p = NULL;
780 		ng_ether_input_orphan_p = NULL;
781 		ng_ether_link_state_p = NULL;
782 		break;
783 
784 	default:
785 		error = EOPNOTSUPP;
786 		break;
787 	}
788 	splx(s);
789 	return (error);
790 }
791 
792