xref: /dflybsd-src/sys/netgraph/ether/ng_ether.c (revision e7b4468ce80913950cd099c393f3ce6ece6fcb2c)
1 
2 /*
3  * ng_ether.c
4  *
5  * Copyright (c) 1996-2000 Whistle Communications, Inc.
6  * All rights reserved.
7  *
8  * Subject to the following obligations and disclaimer of warranty, use and
9  * redistribution of this software, in source or object code forms, with or
10  * without modifications are expressly permitted by Whistle Communications;
11  * provided, however, that:
12  * 1. Any and all reproductions of the source or object code must include the
13  *    copyright notice above and the following disclaimer of warranties; and
14  * 2. No rights are granted, in any manner or form, to use Whistle
15  *    Communications, Inc. trademarks, including the mark "WHISTLE
16  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
17  *    such appears in the above copyright notice or in the software.
18  *
19  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
20  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
21  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
22  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
23  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
24  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
25  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
26  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
27  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
28  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
29  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
30  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
31  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
35  * OF SUCH DAMAGE.
36  *
37  * Authors: Archie Cobbs <archie@freebsd.org>
38  *	    Julian Elischer <julian@freebsd.org>
39  *
40  * $FreeBSD: src/sys/netgraph/ng_ether.c,v 1.2.2.13 2002/07/02 20:10:25 archie Exp $
41  * $DragonFly: src/sys/netgraph/ether/ng_ether.c,v 1.13 2008/01/05 14:02:39 swildner Exp $
42  */
43 
44 /*
45  * ng_ether(4) netgraph node type
46  */
47 
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/kernel.h>
51 #include <sys/malloc.h>
52 #include <sys/mbuf.h>
53 #include <sys/errno.h>
54 #include <sys/syslog.h>
55 #include <sys/socket.h>
56 #include <sys/thread2.h>
57 
58 #include <net/if.h>
59 #include <net/if_types.h>
60 #include <net/if_arp.h>
61 #include <net/if_var.h>
62 #include <net/ethernet.h>
63 
64 #include <netgraph/ng_message.h>
65 #include <netgraph/netgraph.h>
66 #include <netgraph/ng_parse.h>
67 #include "ng_ether.h"
68 
69 #define IFP2AC(IFP)  ((struct arpcom *)IFP)
70 #define IFP2NG(ifp)  (IFP2AC((ifp))->ac_netgraph)
71 
72 /* Per-node private data */
73 struct private {
74 	struct ifnet	*ifp;		/* associated interface */
75 	hook_p		upper;		/* upper hook connection */
76 	hook_p		lower;		/* lower OR orphan hook connection */
77 	u_char		lowerOrphan;	/* whether lower is lower or orphan */
78 	u_char		autoSrcAddr;	/* always overwrite source address */
79 	u_char		promisc;	/* promiscuous mode enabled */
80 	u_long		hwassist;	/* hardware checksum capabilities */
81 };
82 typedef struct private *priv_p;
83 
84 /* Functional hooks called from if_ethersubr.c */
85 static void	ng_ether_input(struct ifnet *ifp,
86 		    struct mbuf **mp, const struct ether_header *eh);
87 static void	ng_ether_input_orphan(struct ifnet *ifp,
88 		    struct mbuf *m, const struct ether_header *eh);
89 static int	ng_ether_output(struct ifnet *ifp, struct mbuf **mp);
90 static void	ng_ether_attach(struct ifnet *ifp);
91 static void	ng_ether_detach(struct ifnet *ifp);
92 
93 /* Other functions */
94 static void	ng_ether_input2(node_p node,
95 		    struct mbuf **mp, const struct ether_header *eh);
96 static int	ng_ether_glueback_header(struct mbuf **mp,
97 			const struct ether_header *eh);
98 static int	ng_ether_rcv_lower(node_p node, struct mbuf *m, meta_p meta);
99 static int	ng_ether_rcv_upper(node_p node, struct mbuf *m, meta_p meta);
100 
101 /* Netgraph node methods */
102 static ng_constructor_t	ng_ether_constructor;
103 static ng_rcvmsg_t	ng_ether_rcvmsg;
104 static ng_shutdown_t	ng_ether_rmnode;
105 static ng_newhook_t	ng_ether_newhook;
106 static ng_rcvdata_t	ng_ether_rcvdata;
107 static ng_disconnect_t	ng_ether_disconnect;
108 static int		ng_ether_mod_event(module_t mod, int event, void *data);
109 
110 /* Parse type for an Ethernet address */
111 static ng_parse_t	ng_enaddr_parse;
112 static ng_unparse_t	ng_enaddr_unparse;
113 const struct ng_parse_type ng_ether_enaddr_type = {
114 	NULL,
115 	NULL,
116 	NULL,
117 	ng_enaddr_parse,
118 	ng_enaddr_unparse,
119 	NULL,			/* no such thing as a "default" EN address */
120 	0
121 };
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_ether_enaddr_type
145 	},
146 	{
147 	  NGM_ETHER_COOKIE,
148 	  NGM_ETHER_SET_ENADDR,
149 	  "setenaddr",
150 	  &ng_ether_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 	{ 0 }
182 };
183 
184 static struct ng_type ng_ether_typestruct = {
185 	NG_VERSION,
186 	NG_ETHER_NODE_TYPE,
187 	ng_ether_mod_event,
188 	ng_ether_constructor,
189 	ng_ether_rcvmsg,
190 	ng_ether_rmnode,
191 	ng_ether_newhook,
192 	NULL,
193 	NULL,
194 	ng_ether_rcvdata,
195 	ng_ether_rcvdata,
196 	ng_ether_disconnect,
197 	ng_ether_cmdlist,
198 };
199 NETGRAPH_INIT(ether, &ng_ether_typestruct);
200 
201 /******************************************************************
202 		    ETHERNET FUNCTION HOOKS
203 ******************************************************************/
204 
205 /*
206  * Handle a packet that has come in on an interface. We get to
207  * look at it here before any upper layer protocols do.
208  *
209  * NOTE: this function will get called at splimp()
210  */
211 static void
212 ng_ether_input(struct ifnet *ifp,
213 	struct mbuf **mp, const struct ether_header *eh)
214 {
215 	const node_p node = IFP2NG(ifp);
216 	const priv_p priv = node->private;
217 
218 	/* If "lower" hook not connected, let packet continue */
219 	if (priv->lower == NULL || priv->lowerOrphan)
220 		return;
221 	ng_ether_input2(node, mp, eh);
222 }
223 
224 /*
225  * Handle a packet that has come in on an interface, and which
226  * does not match any of our known protocols (an ``orphan'').
227  *
228  * NOTE: this function will get called at splimp()
229  */
230 static void
231 ng_ether_input_orphan(struct ifnet *ifp,
232 	struct mbuf *m, const struct ether_header *eh)
233 {
234 	const node_p node = IFP2NG(ifp);
235 	const priv_p priv = node->private;
236 
237 	/* If "orphan" hook not connected, let packet continue */
238 	if (priv->lower == NULL || !priv->lowerOrphan) {
239 		m_freem(m);
240 		return;
241 	}
242 	ng_ether_input2(node, &m, eh);
243 	if (m != NULL)
244 		m_freem(m);
245 }
246 
247 /*
248  * Handle a packet that has come in on an interface.
249  * The Ethernet header has already been detached from the mbuf,
250  * so we have to put it back.
251  *
252  * NOTE: this function will get called at splimp()
253  */
254 static void
255 ng_ether_input2(node_p node, struct mbuf **mp, const struct ether_header *eh)
256 {
257 	const priv_p priv = node->private;
258 	meta_p meta = NULL;
259 	int error;
260 
261 	/* Glue Ethernet header back on */
262 	if ((error = ng_ether_glueback_header(mp, eh)) != 0)
263 		return;
264 
265 	/* Send out lower/orphan hook */
266 	ng_queue_data(priv->lower, *mp, meta);
267 	*mp = NULL;
268 }
269 
270 /*
271  * Handle a packet that is going out on an interface.
272  * The Ethernet header is already attached to the mbuf.
273  */
274 static int
275 ng_ether_output(struct ifnet *ifp, struct mbuf **mp)
276 {
277 	const node_p node = IFP2NG(ifp);
278 	const priv_p priv = node->private;
279 	meta_p meta = NULL;
280 	int error = 0;
281 
282 	/* If "upper" hook not connected, let packet continue */
283 	if (priv->upper == NULL)
284 		return (0);
285 
286 	/* Send it out "upper" hook */
287 	NG_SEND_DATA(error, priv->upper, *mp, meta);
288 	*mp = NULL;
289 	return (error);
290 }
291 
292 /*
293  * A new Ethernet interface has been attached.
294  * Create a new node for it, etc.
295  */
296 static void
297 ng_ether_attach(struct ifnet *ifp)
298 {
299 	char name[IFNAMSIZ + 1];
300 	priv_p priv;
301 	node_p node;
302 
303 	/* Create node */
304 	KASSERT(!IFP2NG(ifp), ("%s: node already exists?", __func__));
305 	strlcpy(name, ifp->if_xname, sizeof(name));
306 	if (ng_make_node_common(&ng_ether_typestruct, &node) != 0) {
307 		log(LOG_ERR, "%s: can't %s for %s\n",
308 		    __func__, "create node", name);
309 		return;
310 	}
311 
312 	/* Allocate private data */
313 	MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
314 	if (priv == NULL) {
315 		log(LOG_ERR, "%s: can't %s for %s\n",
316 		    __func__, "allocate memory", name);
317 		ng_unref(node);
318 		return;
319 	}
320 	node->private = priv;
321 	priv->ifp = ifp;
322 	IFP2NG(ifp) = node;
323 	priv->autoSrcAddr = 1;
324 	priv->hwassist = ifp->if_hwassist;
325 
326 	/* Try to give the node the same name as the interface */
327 	if (ng_name_node(node, name) != 0) {
328 		log(LOG_WARNING, "%s: can't name node %s\n",
329 		    __func__, name);
330 	}
331 }
332 
333 /*
334  * An Ethernet interface is being detached.
335  * Destroy its node.
336  */
337 static void
338 ng_ether_detach(struct ifnet *ifp)
339 {
340 	const node_p node = IFP2NG(ifp);
341 	priv_p priv;
342 
343 	if (node == NULL)		/* no node (why not?), ignore */
344 		return;
345 	ng_rmnode(node);		/* break all links to other nodes */
346 	node->flags |= NG_INVALID;
347 	ng_unname(node);		/* free name (and its reference) */
348 	IFP2NG(ifp) = NULL;		/* detach node from interface */
349 	priv = node->private;		/* free node private info */
350 	bzero(priv, sizeof(*priv));
351 	FREE(priv, M_NETGRAPH);
352 	node->private = NULL;
353 	ng_unref(node);			/* free node itself */
354 }
355 
356 /*
357  * Optimization for gluing the Ethernet header back onto
358  * the front of an incoming packet.
359  */
360 static int
361 ng_ether_glueback_header(struct mbuf **mp, const struct ether_header *eh)
362 {
363 	struct mbuf *m = *mp;
364 	int error = 0;
365 
366 	/*
367 	 * Optimize for the case where the header is already in place
368 	 * at the front of the mbuf. This is actually quite likely
369 	 * because many Ethernet drivers generate packets this way.
370 	 */
371 	if (eh == mtod(m, struct ether_header *) - 1) {
372 		m->m_len += sizeof(*eh);
373 		m->m_data -= sizeof(*eh);
374 		m->m_pkthdr.len += sizeof(*eh);
375 		goto done;
376 	}
377 
378 	/* Prepend the header back onto the front of the mbuf */
379 	M_PREPEND(m, sizeof(*eh), MB_DONTWAIT);
380 	if (m == NULL) {
381 		error = ENOBUFS;
382 		goto done;
383 	}
384 
385 	/* Copy header into front of mbuf */
386 	bcopy(eh, mtod(m, void *), sizeof(*eh));
387 
388 done:
389 	/* Done */
390 	*mp = m;
391 	return error;
392 }
393 
394 /******************************************************************
395 		    NETGRAPH NODE METHODS
396 ******************************************************************/
397 
398 /*
399  * It is not possible or allowable to create a node of this type.
400  * Nodes get created when the interface is attached (or, when
401  * this node type's KLD is loaded).
402  */
403 static int
404 ng_ether_constructor(node_p *nodep)
405 {
406 	return (EINVAL);
407 }
408 
409 /*
410  * Check for attaching a new hook.
411  */
412 static	int
413 ng_ether_newhook(node_p node, hook_p hook, const char *name)
414 {
415 	const priv_p priv = node->private;
416 	u_char orphan = priv->lowerOrphan;
417 	hook_p *hookptr;
418 
419 	/* Divert hook is an alias for lower */
420 	if (strcmp(name, NG_ETHER_HOOK_DIVERT) == 0)
421 		name = NG_ETHER_HOOK_LOWER;
422 
423 	/* Which hook? */
424 	if (strcmp(name, NG_ETHER_HOOK_UPPER) == 0)
425 		hookptr = &priv->upper;
426 	else if (strcmp(name, NG_ETHER_HOOK_LOWER) == 0) {
427 		hookptr = &priv->lower;
428 		orphan = 0;
429 	} else if (strcmp(name, NG_ETHER_HOOK_ORPHAN) == 0) {
430 		hookptr = &priv->lower;
431 		orphan = 1;
432 	} else
433 		return (EINVAL);
434 
435 	/* Check if already connected (shouldn't be, but doesn't hurt) */
436 	if (*hookptr != NULL)
437 		return (EISCONN);
438 
439 	/* Disable hardware checksums while 'upper' hook is connected */
440 	if (hookptr == &priv->upper)
441 		priv->ifp->if_hwassist = 0;
442 
443 	/* OK */
444 	*hookptr = hook;
445 	priv->lowerOrphan = orphan;
446 	return (0);
447 }
448 
449 /*
450  * Receive an incoming control message.
451  */
452 static int
453 ng_ether_rcvmsg(node_p node, struct ng_mesg *msg,
454 	const char *retaddr, struct ng_mesg **rptr)
455 {
456 	const priv_p priv = node->private;
457 	struct ng_mesg *resp = NULL;
458 	int error = 0;
459 
460 	switch (msg->header.typecookie) {
461 	case NGM_ETHER_COOKIE:
462 		switch (msg->header.cmd) {
463 		case NGM_ETHER_GET_IFNAME:
464 			NG_MKRESPONSE(resp, msg, IFNAMSIZ + 1, M_NOWAIT);
465 			if (resp == NULL) {
466 				error = ENOMEM;
467 				break;
468 			}
469 			strlcpy(resp->data, priv->ifp->if_xname, IFNAMSIZ);
470 			break;
471 		case NGM_ETHER_GET_IFINDEX:
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->ifp->if_index;
478 			break;
479 		case NGM_ETHER_GET_ENADDR:
480 			NG_MKRESPONSE(resp, msg, ETHER_ADDR_LEN, M_NOWAIT);
481 			if (resp == NULL) {
482 				error = ENOMEM;
483 				break;
484 			}
485 			bcopy((IFP2AC(priv->ifp))->ac_enaddr,
486 			    resp->data, ETHER_ADDR_LEN);
487 			break;
488 		case NGM_ETHER_SET_ENADDR:
489 		    {
490 			if (msg->header.arglen != ETHER_ADDR_LEN) {
491 				error = EINVAL;
492 				break;
493 			}
494 			error = if_setlladdr(priv->ifp,
495 			    (u_char *)msg->data, ETHER_ADDR_LEN);
496 			break;
497 		    }
498 		case NGM_ETHER_GET_PROMISC:
499 			NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
500 			if (resp == NULL) {
501 				error = ENOMEM;
502 				break;
503 			}
504 			*((u_int32_t *)resp->data) = priv->promisc;
505 			break;
506 		case NGM_ETHER_SET_PROMISC:
507 		    {
508 			u_char want;
509 
510 			if (msg->header.arglen != sizeof(u_int32_t)) {
511 				error = EINVAL;
512 				break;
513 			}
514 			want = !!*((u_int32_t *)msg->data);
515 			if (want ^ priv->promisc) {
516 				if ((error = ifpromisc(priv->ifp, want)) != 0)
517 					break;
518 				priv->promisc = want;
519 			}
520 			break;
521 		    }
522 		case NGM_ETHER_GET_AUTOSRC:
523 			NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
524 			if (resp == NULL) {
525 				error = ENOMEM;
526 				break;
527 			}
528 			*((u_int32_t *)resp->data) = priv->autoSrcAddr;
529 			break;
530 		case NGM_ETHER_SET_AUTOSRC:
531 			if (msg->header.arglen != sizeof(u_int32_t)) {
532 				error = EINVAL;
533 				break;
534 			}
535 			priv->autoSrcAddr = !!*((u_int32_t *)msg->data);
536 			break;
537 		default:
538 			error = EINVAL;
539 			break;
540 		}
541 		break;
542 	default:
543 		error = EINVAL;
544 		break;
545 	}
546 	if (rptr)
547 		*rptr = resp;
548 	else if (resp != NULL)
549 		FREE(resp, M_NETGRAPH);
550 	FREE(msg, M_NETGRAPH);
551 	return (error);
552 }
553 
554 /*
555  * Receive data on a hook.
556  */
557 static int
558 ng_ether_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
559 {
560 	const node_p node = hook->node;
561 	const priv_p priv = node->private;
562 
563 	if (hook == priv->lower)
564 		return ng_ether_rcv_lower(node, m, meta);
565 	if (hook == priv->upper)
566 		return ng_ether_rcv_upper(node, m, meta);
567 	panic("%s: weird hook", __func__);
568 }
569 
570 /*
571  * Handle an mbuf received on the "lower" hook.
572  */
573 static int
574 ng_ether_rcv_lower(node_p node, struct mbuf *m, meta_p meta)
575 {
576 	const priv_p priv = node->private;
577  	struct ifnet *const ifp = priv->ifp;
578 	int error;
579 
580 	/* Discard meta info */
581 	NG_FREE_META(meta);
582 
583 	/* Check whether interface is ready for packets */
584 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) {
585 		m_freem(m);
586 		return (ENETDOWN);
587 	}
588 
589 	/* Make sure header is fully pulled up */
590 	if (m->m_pkthdr.len < sizeof(struct ether_header)) {
591 		m_freem(m);
592 		return (EINVAL);
593 	}
594 	if (m->m_len < sizeof(struct ether_header)
595 	    && (m = m_pullup(m, sizeof(struct ether_header))) == NULL)
596 		return (ENOBUFS);
597 
598 	/* Drop in the MAC address if desired */
599 	if (priv->autoSrcAddr) {
600 
601 		/* Make the mbuf writable if it's not already */
602 		if (!M_WRITABLE(m)
603 		    && (m = m_pullup(m, sizeof(struct ether_header))) == NULL)
604 			return (ENOBUFS);
605 
606 		/* Overwrite source MAC address */
607 		bcopy((IFP2AC(ifp))->ac_enaddr,
608 		    mtod(m, struct ether_header *)->ether_shost,
609 		    ETHER_ADDR_LEN);
610 	}
611 
612 	/* Send it on its way */
613 	lwkt_serialize_enter(ifp->if_serializer);
614 	error = ether_output_frame(ifp, m);
615 	lwkt_serialize_exit(ifp->if_serializer);
616 
617 	return (error);
618 }
619 
620 /*
621  * Handle an mbuf received on the "upper" hook.
622  */
623 static int
624 ng_ether_rcv_upper(node_p node, struct mbuf *m, meta_p meta)
625 {
626 	const priv_p priv = node->private;
627 	struct ether_header *eh;
628 
629 	/* Discard meta info */
630 	NG_FREE_META(meta);
631 
632 	/* Check length and pull off header */
633 	if (m->m_pkthdr.len < sizeof(*eh)) {
634 		m_freem(m);
635 		return (EINVAL);
636 	}
637 	if (m->m_len < sizeof(*eh) && (m = m_pullup(m, sizeof(*eh))) == NULL)
638 		return (ENOBUFS);
639 	eh = mtod(m, struct ether_header *);
640 	m->m_data += sizeof(*eh);
641 	m->m_len -= sizeof(*eh);
642 	m->m_pkthdr.len -= sizeof(*eh);
643 	m->m_pkthdr.rcvif = priv->ifp;
644 
645 	/* Route packet back in */
646 	lwkt_serialize_enter(priv->ifp->if_serializer);
647 	ether_demux(priv->ifp, eh, m);
648 	lwkt_serialize_exit(priv->ifp->if_serializer);
649 	return (0);
650 }
651 
652 /*
653  * Shutdown node. This resets the node but does not remove it.
654  */
655 static int
656 ng_ether_rmnode(node_p node)
657 {
658 	const priv_p priv = node->private;
659 
660 	ng_cutlinks(node);
661 	node->flags &= ~NG_INVALID;	/* bounce back to life */
662 	if (priv->promisc) {		/* disable promiscuous mode */
663 		ifpromisc(priv->ifp, 0);
664 		priv->promisc = 0;
665 	}
666 	priv->autoSrcAddr = 1;		/* reset auto-src-addr flag */
667 	return (0);
668 }
669 
670 /*
671  * Hook disconnection.
672  */
673 static int
674 ng_ether_disconnect(hook_p hook)
675 {
676 	const priv_p priv = hook->node->private;
677 
678 	if (hook == priv->upper) {
679 		priv->upper = NULL;
680 		priv->ifp->if_hwassist = priv->hwassist;  /* restore h/w csum */
681 	} else if (hook == priv->lower) {
682 		priv->lower = NULL;
683 		priv->lowerOrphan = 0;
684 	} else
685 		panic("%s: weird hook", __func__);
686 	if (hook->node->numhooks == 0)
687 		ng_rmnode(hook->node);	/* reset node */
688 	return (0);
689 }
690 
691 static int
692 ng_enaddr_parse(const struct ng_parse_type *type,
693 	const char *s, int *const off, const u_char *const start,
694 	u_char *const buf, int *const buflen)
695 {
696 	char *eptr;
697 	u_long val;
698 	int i;
699 
700 	if (*buflen < ETHER_ADDR_LEN)
701 		return (ERANGE);
702 	for (i = 0; i < ETHER_ADDR_LEN; i++) {
703 		val = strtoul(s + *off, &eptr, 16);
704 		if (val > 0xff || eptr == s + *off)
705 			return (EINVAL);
706 		buf[i] = (u_char)val;
707 		*off = (eptr - s);
708 		if (i < ETHER_ADDR_LEN - 1) {
709 			if (*eptr != ':')
710 				return (EINVAL);
711 			(*off)++;
712 		}
713 	}
714 	*buflen = ETHER_ADDR_LEN;
715 	return (0);
716 }
717 
718 static int
719 ng_enaddr_unparse(const struct ng_parse_type *type,
720 	const u_char *data, int *off, char *cbuf, int cbuflen)
721 {
722 	int len;
723 
724 	len = ksnprintf(cbuf, cbuflen, "%02x:%02x:%02x:%02x:%02x:%02x",
725 	    data[*off], data[*off + 1], data[*off + 2],
726 	    data[*off + 3], data[*off + 4], data[*off + 5]);
727 	if (len >= cbuflen)
728 		return (ERANGE);
729 	*off += ETHER_ADDR_LEN;
730 	return (0);
731 }
732 
733 /******************************************************************
734 		    	INITIALIZATION
735 ******************************************************************/
736 
737 /*
738  * Handle loading and unloading for this node type.
739  */
740 static int
741 ng_ether_mod_event(module_t mod, int event, void *data)
742 {
743 	struct ifnet *ifp;
744 	int error = 0;
745 
746 	crit_enter();
747 	switch (event) {
748 	case MOD_LOAD:
749 
750 		/* Register function hooks */
751 		if (ng_ether_attach_p != NULL) {
752 			error = EEXIST;
753 			break;
754 		}
755 		ng_ether_attach_p = ng_ether_attach;
756 		ng_ether_detach_p = ng_ether_detach;
757 		ng_ether_output_p = ng_ether_output;
758 		ng_ether_input_p = ng_ether_input;
759 		ng_ether_input_orphan_p = ng_ether_input_orphan;
760 
761 		/* Create nodes for any already-existing Ethernet interfaces */
762 		TAILQ_FOREACH(ifp, &ifnet, if_link) {
763 			if (ifp->if_type == IFT_ETHER ||
764 			    ifp->if_type == IFT_L2VLAN)
765 				ng_ether_attach(ifp);
766 		}
767 		break;
768 
769 	case MOD_UNLOAD:
770 
771 		/*
772 		 * Note that the base code won't try to unload us until
773 		 * all nodes have been removed, and that can't happen
774 		 * until all Ethernet interfaces are removed. In any
775 		 * case, we know there are no nodes left if the action
776 		 * is MOD_UNLOAD, so there's no need to detach any nodes.
777 		 */
778 
779 		/* Unregister function hooks */
780 		ng_ether_attach_p = NULL;
781 		ng_ether_detach_p = NULL;
782 		ng_ether_output_p = NULL;
783 		ng_ether_input_p = NULL;
784 		ng_ether_input_orphan_p = NULL;
785 		break;
786 
787 	default:
788 		error = EOPNOTSUPP;
789 		break;
790 	}
791 	crit_exit();
792 	return (error);
793 }
794 
795