xref: /freebsd/sys/netgraph/ng_pppoe.c (revision 39beb93c3f8bdbf72a61fda42300b5ebed7390c8)
1 /*
2  * ng_pppoe.c
3  */
4 
5 /*-
6  * Copyright (c) 1996-1999 Whistle Communications, Inc.
7  * All rights reserved.
8  *
9  * Subject to the following obligations and disclaimer of warranty, use and
10  * redistribution of this software, in source or object code forms, with or
11  * without modifications are expressly permitted by Whistle Communications;
12  * provided, however, that:
13  * 1. Any and all reproductions of the source or object code must include the
14  *    copyright notice above and the following disclaimer of warranties; and
15  * 2. No rights are granted, in any manner or form, to use Whistle
16  *    Communications, Inc. trademarks, including the mark "WHISTLE
17  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
18  *    such appears in the above copyright notice or in the software.
19  *
20  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
21  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
22  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
23  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
24  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
25  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
26  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
27  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
28  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
29  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
30  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
31  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
32  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
36  * OF SUCH DAMAGE.
37  *
38  * Author: Julian Elischer <julian@freebsd.org>
39  *
40  * $FreeBSD$
41  * $Whistle: ng_pppoe.c,v 1.10 1999/11/01 09:24:52 julian Exp $
42  */
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/kernel.h>
47 #include <sys/ktr.h>
48 #include <sys/mbuf.h>
49 #include <sys/malloc.h>
50 #include <sys/errno.h>
51 #include <sys/syslog.h>
52 #include <net/ethernet.h>
53 
54 #include <netgraph/ng_message.h>
55 #include <netgraph/netgraph.h>
56 #include <netgraph/ng_parse.h>
57 #include <netgraph/ng_pppoe.h>
58 #include <netgraph/ng_ether.h>
59 
60 #ifdef NG_SEPARATE_MALLOC
61 MALLOC_DEFINE(M_NETGRAPH_PPPOE, "netgraph_pppoe", "netgraph pppoe node");
62 #else
63 #define M_NETGRAPH_PPPOE M_NETGRAPH
64 #endif
65 
66 #define SIGNOFF "session closed"
67 
68 /*
69  * This section contains the netgraph method declarations for the
70  * pppoe node. These methods define the netgraph pppoe 'type'.
71  */
72 
73 static ng_constructor_t	ng_pppoe_constructor;
74 static ng_rcvmsg_t	ng_pppoe_rcvmsg;
75 static ng_shutdown_t	ng_pppoe_shutdown;
76 static ng_newhook_t	ng_pppoe_newhook;
77 static ng_connect_t	ng_pppoe_connect;
78 static ng_rcvdata_t	ng_pppoe_rcvdata;
79 static ng_rcvdata_t	ng_pppoe_rcvdata_ether;
80 static ng_rcvdata_t	ng_pppoe_rcvdata_debug;
81 static ng_disconnect_t	ng_pppoe_disconnect;
82 
83 /* Parse type for struct ngpppoe_init_data */
84 static const struct ng_parse_struct_field ngpppoe_init_data_type_fields[]
85 	= NG_PPPOE_INIT_DATA_TYPE_INFO;
86 static const struct ng_parse_type ngpppoe_init_data_state_type = {
87 	&ng_parse_struct_type,
88 	&ngpppoe_init_data_type_fields
89 };
90 
91 /* Parse type for struct ngpppoe_sts */
92 static const struct ng_parse_struct_field ng_pppoe_sts_type_fields[]
93 	= NG_PPPOE_STS_TYPE_INFO;
94 static const struct ng_parse_type ng_pppoe_sts_state_type = {
95 	&ng_parse_struct_type,
96 	&ng_pppoe_sts_type_fields
97 };
98 
99 /* List of commands and how to convert arguments to/from ASCII */
100 static const struct ng_cmdlist ng_pppoe_cmds[] = {
101 	{
102 	  NGM_PPPOE_COOKIE,
103 	  NGM_PPPOE_CONNECT,
104 	  "pppoe_connect",
105 	  &ngpppoe_init_data_state_type,
106 	  NULL
107 	},
108 	{
109 	  NGM_PPPOE_COOKIE,
110 	  NGM_PPPOE_LISTEN,
111 	  "pppoe_listen",
112 	  &ngpppoe_init_data_state_type,
113 	  NULL
114 	},
115 	{
116 	  NGM_PPPOE_COOKIE,
117 	  NGM_PPPOE_OFFER,
118 	  "pppoe_offer",
119 	  &ngpppoe_init_data_state_type,
120 	  NULL
121 	},
122 	{
123 	  NGM_PPPOE_COOKIE,
124 	  NGM_PPPOE_SERVICE,
125 	  "pppoe_service",
126 	  &ngpppoe_init_data_state_type,
127 	  NULL
128 	},
129 	{
130 	  NGM_PPPOE_COOKIE,
131 	  NGM_PPPOE_SUCCESS,
132 	  "pppoe_success",
133 	  &ng_pppoe_sts_state_type,
134 	  NULL
135 	},
136 	{
137 	  NGM_PPPOE_COOKIE,
138 	  NGM_PPPOE_FAIL,
139 	  "pppoe_fail",
140 	  &ng_pppoe_sts_state_type,
141 	  NULL
142 	},
143 	{
144 	  NGM_PPPOE_COOKIE,
145 	  NGM_PPPOE_CLOSE,
146 	  "pppoe_close",
147 	  &ng_pppoe_sts_state_type,
148 	  NULL
149 	},
150 	{
151 	  NGM_PPPOE_COOKIE,
152 	  NGM_PPPOE_SETMODE,
153 	  "pppoe_setmode",
154 	  &ng_parse_string_type,
155 	  NULL
156 	},
157 	{
158 	  NGM_PPPOE_COOKIE,
159 	  NGM_PPPOE_GETMODE,
160 	  "pppoe_getmode",
161 	  NULL,
162 	  &ng_parse_string_type
163 	},
164 	{
165 	  NGM_PPPOE_COOKIE,
166 	  NGM_PPPOE_SETENADDR,
167 	  "setenaddr",
168 	  &ng_parse_enaddr_type,
169 	  NULL
170 	},
171 	{ 0 }
172 };
173 
174 /* Netgraph node type descriptor */
175 static struct ng_type typestruct = {
176 	.version =	NG_ABI_VERSION,
177 	.name =		NG_PPPOE_NODE_TYPE,
178 	.constructor =	ng_pppoe_constructor,
179 	.rcvmsg =	ng_pppoe_rcvmsg,
180 	.shutdown =	ng_pppoe_shutdown,
181 	.newhook =	ng_pppoe_newhook,
182 	.connect =	ng_pppoe_connect,
183 	.rcvdata =	ng_pppoe_rcvdata,
184 	.disconnect =	ng_pppoe_disconnect,
185 	.cmdlist =	ng_pppoe_cmds,
186 };
187 NETGRAPH_INIT(pppoe, &typestruct);
188 
189 /*
190  * States for the session state machine.
191  * These have no meaning if there is no hook attached yet.
192  */
193 enum state {
194     PPPOE_SNONE=0,	/* [both] Initial state */
195     PPPOE_LISTENING,	/* [Daemon] Listening for discover initiation pkt */
196     PPPOE_SINIT,	/* [Client] Sent discovery initiation */
197     PPPOE_PRIMED,	/* [Server] Awaiting PADI from daemon */
198     PPPOE_SOFFER,	/* [Server] Sent offer message  (got PADI)*/
199     PPPOE_SREQ,		/* [Client] Sent a Request */
200     PPPOE_NEWCONNECTED,	/* [Server] Connection established, No data received */
201     PPPOE_CONNECTED,	/* [Both] Connection established, Data received */
202     PPPOE_DEAD		/* [Both] */
203 };
204 
205 #define NUMTAGS 20 /* number of tags we are set up to work with */
206 
207 /*
208  * Information we store for each hook on each node for negotiating the
209  * session. The mbuf and cluster are freed once negotiation has completed.
210  * The whole negotiation block is then discarded.
211  */
212 
213 struct sess_neg {
214 	struct mbuf 		*m; /* holds cluster with last sent packet */
215 	union	packet		*pkt; /* points within the above cluster */
216 	struct callout		handle;   /* see timeout(9) */
217 	u_int			timeout; /* 0,1,2,4,8,16 etc. seconds */
218 	u_int			numtags;
219 	const struct pppoe_tag	*tags[NUMTAGS];
220 	u_int			service_len;
221 	u_int			ac_name_len;
222 
223 	struct datatag		service;
224 	struct datatag		ac_name;
225 };
226 typedef struct sess_neg *negp;
227 
228 /*
229  * Session information that is needed after connection.
230  */
231 struct sess_con {
232 	hook_p  		hook;
233 	uint16_t		Session_ID;
234 	enum state		state;
235 	ng_ID_t			creator;	/* who to notify */
236 	struct pppoe_full_hdr	pkt_hdr;	/* used when connected */
237 	negp			neg;		/* used when negotiating */
238 	LIST_ENTRY(sess_con)	sessions;
239 };
240 typedef struct sess_con *sessp;
241 
242 #define SESSHASHSIZE	0x0100
243 #define SESSHASH(x)	(((x) ^ ((x) >> 8)) & (SESSHASHSIZE - 1))
244 
245 struct sess_hash_entry {
246 	struct mtx	mtx;
247 	LIST_HEAD(hhead, sess_con) head;
248 };
249 
250 /*
251  * Information we store for each node
252  */
253 struct PPPoE {
254 	node_p		node;		/* back pointer to node */
255 	hook_p  	ethernet_hook;
256 	hook_p  	debug_hook;
257 	u_int   	packets_in;	/* packets in from ethernet */
258 	u_int   	packets_out;	/* packets out towards ethernet */
259 	uint32_t	flags;
260 #define	COMPAT_3COM	0x00000001
261 #define	COMPAT_DLINK	0x00000002
262 	struct ether_header	eh;
263 	LIST_HEAD(, sess_con) listeners;
264 	struct sess_hash_entry	sesshash[SESSHASHSIZE];
265 };
266 typedef struct PPPoE *priv_p;
267 
268 union uniq {
269 	char bytes[sizeof(void *)];
270 	void *pointer;
271 };
272 
273 #define	LEAVE(x) do { error = x; goto quit; } while(0)
274 static void	pppoe_start(sessp sp);
275 static void	pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2);
276 static const	struct pppoe_tag *scan_tags(sessp sp,
277 			const struct pppoe_hdr* ph);
278 static	int	pppoe_send_event(sessp sp, enum cmd cmdid);
279 
280 /*************************************************************************
281  * Some basic utilities  from the Linux version with author's permission.*
282  * Author:	Michal Ostrowski <mostrows@styx.uwaterloo.ca>		 *
283  ************************************************************************/
284 
285 
286 
287 /*
288  * Return the location where the next tag can be put
289  */
290 static __inline const struct pppoe_tag*
291 next_tag(const struct pppoe_hdr* ph)
292 {
293 	return (const struct pppoe_tag*)(((const char*)&ph->tag[0])
294 	    + ntohs(ph->length));
295 }
296 
297 /*
298  * Look for a tag of a specific type.
299  * Don't trust any length the other end says,
300  * but assume we already sanity checked ph->length.
301  */
302 static const struct pppoe_tag*
303 get_tag(const struct pppoe_hdr* ph, uint16_t idx)
304 {
305 	const char *const end = (const char *)next_tag(ph);
306 	const struct pppoe_tag *pt = &ph->tag[0];
307 	const char *ptn;
308 
309 	/*
310 	 * Keep processing tags while a tag header will still fit.
311 	 */
312 	while((const char*)(pt + 1) <= end) {
313 		/*
314 		 * If the tag data would go past the end of the packet, abort.
315 		 */
316 		ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
317 		if (ptn > end) {
318 			CTR2(KTR_NET, "%20s: invalid length for tag %d",
319 			    __func__, idx);
320 			return (NULL);
321 		}
322 		if (pt->tag_type == idx) {
323 			CTR2(KTR_NET, "%20s: found tag %d", __func__, idx);
324 			return (pt);
325 		}
326 
327 		pt = (const struct pppoe_tag*)ptn;
328 	}
329 
330 	CTR2(KTR_NET, "%20s: not found tag %d", __func__, idx);
331 	return (NULL);
332 }
333 
334 /**************************************************************************
335  * Inlines to initialise or add tags to a session's tag list.
336  **************************************************************************/
337 /*
338  * Initialise the session's tag list.
339  */
340 static void
341 init_tags(sessp sp)
342 {
343 	KASSERT(sp->neg != NULL, ("%s: no neg", __func__));
344 	sp->neg->numtags = 0;
345 }
346 
347 static void
348 insert_tag(sessp sp, const struct pppoe_tag *tp)
349 {
350 	negp neg = sp->neg;
351 	int i;
352 
353 	KASSERT(neg != NULL, ("%s: no neg", __func__));
354 	if ((i = neg->numtags++) < NUMTAGS) {
355 		neg->tags[i] = tp;
356 	} else {
357 		log(LOG_NOTICE, "ng_pppoe: asked to add too many tags to "
358 		    "packet\n");
359 		neg->numtags--;
360 	}
361 }
362 
363 /*
364  * Make up a packet, using the tags filled out for the session.
365  *
366  * Assume that the actual pppoe header and ethernet header
367  * are filled out externally to this routine.
368  * Also assume that neg->wh points to the correct
369  * location at the front of the buffer space.
370  */
371 static void
372 make_packet(sessp sp) {
373 	struct pppoe_full_hdr *wh = &sp->neg->pkt->pkt_header;
374 	const struct pppoe_tag **tag;
375 	char *dp;
376 	int count;
377 	int tlen;
378 	uint16_t length = 0;
379 
380 	KASSERT((sp->neg != NULL) && (sp->neg->m != NULL),
381 	    ("%s: called from wrong state", __func__));
382 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
383 
384 	dp = (char *)wh->ph.tag;
385 	for (count = 0, tag = sp->neg->tags;
386 	    ((count < sp->neg->numtags) && (count < NUMTAGS));
387 	    tag++, count++) {
388 		tlen = ntohs((*tag)->tag_len) + sizeof(**tag);
389 		if ((length + tlen) > (ETHER_MAX_LEN - 4 - sizeof(*wh))) {
390 			log(LOG_NOTICE, "ng_pppoe: tags too long\n");
391 			sp->neg->numtags = count;
392 			break;	/* XXX chop off what's too long */
393 		}
394 		bcopy(*tag, (char *)dp, tlen);
395 		length += tlen;
396 		dp += tlen;
397 	}
398  	wh->ph.length = htons(length);
399 	sp->neg->m->m_len = length + sizeof(*wh);
400 	sp->neg->m->m_pkthdr.len = length + sizeof(*wh);
401 }
402 
403 /**************************************************************************
404  * Routines to match a service.						  *
405  **************************************************************************/
406 
407 /*
408  * Find a hook that has a service string that matches that
409  * we are seeking. For now use a simple string.
410  * In the future we may need something like regexp().
411  *
412  * Null string is a wildcard (ANY service), according to RFC2516.
413  * And historical FreeBSD wildcard is also "*".
414  */
415 
416 static hook_p
417 pppoe_match_svc(node_p node, const struct pppoe_tag *tag)
418 {
419 	const priv_p privp = NG_NODE_PRIVATE(node);
420 	sessp sp;
421 
422 	LIST_FOREACH(sp, &privp->listeners, sessions) {
423 		negp neg = sp->neg;
424 
425 		/* Empty Service-Name matches any service. */
426 		if (neg->service_len == 0)
427 			break;
428 
429 		/* Special case for a blank or "*" service name (wildcard). */
430 		if (neg->service_len == 1 && neg->service.data[0] == '*')
431 			break;
432 
433 		/* If the lengths don't match, that aint it. */
434 		if (neg->service_len != ntohs(tag->tag_len))
435 			continue;
436 
437 		if (strncmp(tag->tag_data, neg->service.data,
438 		    ntohs(tag->tag_len)) == 0)
439 			break;
440 	}
441 	CTR3(KTR_NET, "%20s: matched %p for %s", __func__,
442 	    sp?sp->hook:NULL, tag->tag_data);
443 
444 	return (sp?sp->hook:NULL);
445 }
446 
447 /*
448  * Broadcast the PADI packet in m0 to all listening hooks.
449  * This routine is called when a PADI with empty Service-Name
450  * tag is received. Client should receive PADOs with all
451  * available services.
452  */
453 static int
454 pppoe_broadcast_padi(node_p node, struct mbuf *m0)
455 {
456 	const priv_p privp = NG_NODE_PRIVATE(node);
457 	sessp sp;
458 	int error = 0;
459 
460 	LIST_FOREACH(sp, &privp->listeners, sessions) {
461 		struct mbuf *m;
462 
463 		m = m_dup(m0, M_DONTWAIT);
464 		if (m == NULL)
465 			return (ENOMEM);
466 		NG_SEND_DATA_ONLY(error, sp->hook, m);
467 		if (error)
468 			return (error);
469 	}
470 
471 	return (0);
472 }
473 
474 /*
475  * Find a hook, which name equals to given service.
476  */
477 static hook_p
478 pppoe_find_svc(node_p node, const char *svc_name, int svc_len)
479 {
480 	const priv_p privp = NG_NODE_PRIVATE(node);
481 	sessp sp;
482 
483 	LIST_FOREACH(sp, &privp->listeners, sessions) {
484 		negp neg = sp->neg;
485 
486 		if (neg->service_len == svc_len &&
487 		    strncmp(svc_name, neg->service.data, svc_len) == 0)
488 			return (sp->hook);
489 	}
490 
491 	return (NULL);
492 }
493 
494 /**************************************************************************
495  * Routines to find a particular session that matches an incoming packet. *
496  **************************************************************************/
497 /* Find free session and add to hash. */
498 static uint16_t
499 pppoe_getnewsession(sessp sp)
500 {
501 	const priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
502 	static uint16_t pppoe_sid = 1;
503 	sessp	tsp;
504 	uint16_t val, hash;
505 
506 restart:
507 	/* Atomicity is not needed here as value will be checked. */
508 	val = pppoe_sid++;
509 	/* Spec says 0xFFFF is reserved, also don't use 0x0000. */
510 	if (val == 0xffff || val == 0x0000)
511 		val = pppoe_sid = 1;
512 
513 	/* Check it isn't already in use. */
514 	hash = SESSHASH(val);
515 	mtx_lock(&privp->sesshash[hash].mtx);
516 	LIST_FOREACH(tsp, &privp->sesshash[hash].head, sessions) {
517 		if (tsp->Session_ID == val)
518 			break;
519 	}
520 	if (!tsp) {
521 		sp->Session_ID = val;
522 		LIST_INSERT_HEAD(&privp->sesshash[hash].head, sp, sessions);
523 	}
524 	mtx_unlock(&privp->sesshash[hash].mtx);
525 	if (tsp)
526 		goto restart;
527 
528 	CTR2(KTR_NET, "%20s: new sid %d", __func__, val);
529 
530 	return (val);
531 }
532 
533 /* Add specified session to hash. */
534 static void
535 pppoe_addsession(sessp sp)
536 {
537 	const priv_p	privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
538 	uint16_t	hash = SESSHASH(sp->Session_ID);
539 
540 	mtx_lock(&privp->sesshash[hash].mtx);
541 	LIST_INSERT_HEAD(&privp->sesshash[hash].head, sp, sessions);
542 	mtx_unlock(&privp->sesshash[hash].mtx);
543 }
544 
545 /* Delete specified session from hash. */
546 static void
547 pppoe_delsession(sessp sp)
548 {
549 	const priv_p	privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
550 	uint16_t	hash = SESSHASH(sp->Session_ID);
551 
552 	mtx_lock(&privp->sesshash[hash].mtx);
553 	LIST_REMOVE(sp, sessions);
554 	mtx_unlock(&privp->sesshash[hash].mtx);
555 }
556 
557 /* Find matching peer/session combination. */
558 static sessp
559 pppoe_findsession(priv_p privp, const struct pppoe_full_hdr *wh)
560 {
561 	uint16_t 	session = ntohs(wh->ph.sid);
562 	uint16_t	hash = SESSHASH(session);
563 	sessp		sp = NULL;
564 
565 	mtx_lock(&privp->sesshash[hash].mtx);
566 	LIST_FOREACH(sp, &privp->sesshash[hash].head, sessions) {
567 		if (sp->Session_ID == session &&
568 		    bcmp(sp->pkt_hdr.eh.ether_dhost,
569 		     wh->eh.ether_shost, ETHER_ADDR_LEN) == 0) {
570 			break;
571 		}
572 	}
573 	mtx_unlock(&privp->sesshash[hash].mtx);
574 	CTR3(KTR_NET, "%20s: matched %p for %d", __func__, sp?sp->hook:NULL,
575 	    session);
576 
577 	return (sp);
578 }
579 
580 static hook_p
581 pppoe_finduniq(node_p node, const struct pppoe_tag *tag)
582 {
583 	hook_p	hook = NULL;
584 	union uniq uniq;
585 
586 	bcopy(tag->tag_data, uniq.bytes, sizeof(void *));
587 	/* Cycle through all known hooks. */
588 	LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
589 		/* Skip any nonsession hook. */
590 		if (NG_HOOK_PRIVATE(hook) == NULL)
591 			continue;
592 		if (uniq.pointer == NG_HOOK_PRIVATE(hook))
593 			break;
594 	}
595 	CTR3(KTR_NET, "%20s: matched %p for %p", __func__, hook, uniq.pointer);
596 
597 	return (hook);
598 }
599 
600 /**************************************************************************
601  * Start of Netgraph entrypoints.					  *
602  **************************************************************************/
603 
604 /*
605  * Allocate the private data structure and link it with node.
606  */
607 static int
608 ng_pppoe_constructor(node_p node)
609 {
610 	priv_p	privp;
611 	int	i;
612 
613 	/* Initialize private descriptor. */
614 	privp = malloc(sizeof(*privp), M_NETGRAPH_PPPOE, M_NOWAIT | M_ZERO);
615 	if (privp == NULL)
616 		return (ENOMEM);
617 
618 	/* Link structs together; this counts as our one reference to *node. */
619 	NG_NODE_SET_PRIVATE(node, privp);
620 	privp->node = node;
621 
622 	/* Initialize to standard mode. */
623 	memset(&privp->eh.ether_dhost, 0xff, ETHER_ADDR_LEN);
624 	privp->eh.ether_type = ETHERTYPE_PPPOE_DISC;
625 
626 	LIST_INIT(&privp->listeners);
627 	for (i = 0; i < SESSHASHSIZE; i++) {
628 	    mtx_init(&privp->sesshash[i].mtx, "PPPoE hash mutex", NULL, MTX_DEF);
629 	    LIST_INIT(&privp->sesshash[i].head);
630 	}
631 
632 	CTR3(KTR_NET, "%20s: created node [%x] (%p)",
633 	    __func__, node->nd_ID, node);
634 
635 	return (0);
636 }
637 
638 /*
639  * Give our ok for a hook to be added...
640  * point the hook's private info to the hook structure.
641  *
642  * The following hook names are special:
643  *  "ethernet":  the hook that should be connected to a NIC.
644  *  "debug":	copies of data sent out here  (when I write the code).
645  * All other hook names need only be unique. (the framework checks this).
646  */
647 static int
648 ng_pppoe_newhook(node_p node, hook_p hook, const char *name)
649 {
650 	const priv_p privp = NG_NODE_PRIVATE(node);
651 	sessp sp;
652 
653 	if (strcmp(name, NG_PPPOE_HOOK_ETHERNET) == 0) {
654 		privp->ethernet_hook = hook;
655 		NG_HOOK_SET_RCVDATA(hook, ng_pppoe_rcvdata_ether);
656 	} else if (strcmp(name, NG_PPPOE_HOOK_DEBUG) == 0) {
657 		privp->debug_hook = hook;
658 		NG_HOOK_SET_RCVDATA(hook, ng_pppoe_rcvdata_debug);
659 	} else {
660 		/*
661 		 * Any other unique name is OK.
662 		 * The infrastructure has already checked that it's unique,
663 		 * so just allocate it and hook it in.
664 		 */
665 		sp = malloc(sizeof(*sp), M_NETGRAPH_PPPOE, M_NOWAIT | M_ZERO);
666 		if (sp == NULL)
667 			return (ENOMEM);
668 
669 		NG_HOOK_SET_PRIVATE(hook, sp);
670 		sp->hook = hook;
671 	}
672 	CTR5(KTR_NET, "%20s: node [%x] (%p) connected hook %s (%p)",
673 	    __func__, node->nd_ID, node, name, hook);
674 
675 	return(0);
676 }
677 
678 /*
679  * Hook has been added successfully. Request the MAC address of
680  * the underlying Ethernet node.
681  */
682 static int
683 ng_pppoe_connect(hook_p hook)
684 {
685 	const priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
686 	struct ng_mesg *msg;
687 	int error;
688 
689 	if (hook != privp->ethernet_hook)
690 		return (0);
691 
692 	/*
693 	 * If this is Ethernet hook, then request MAC address
694 	 * from our downstream.
695 	 */
696 	NG_MKMESSAGE(msg, NGM_ETHER_COOKIE, NGM_ETHER_GET_ENADDR, 0, M_NOWAIT);
697 	if (msg == NULL)
698 		return (ENOBUFS);
699 
700 	/*
701 	 * Our hook and peer hook have HK_INVALID flag set,
702 	 * so we can't use NG_SEND_MSG_HOOK() macro here.
703 	 */
704 	NG_SEND_MSG_ID(error, privp->node, msg,
705 	    NG_NODE_ID(NG_PEER_NODE(privp->ethernet_hook)),
706 	    NG_NODE_ID(privp->node));
707 
708 	return (error);
709 }
710 /*
711  * Get a netgraph control message.
712  * Check it is one we understand. If needed, send a response.
713  * We sometimes save the address for an async action later.
714  * Always free the message.
715  */
716 static int
717 ng_pppoe_rcvmsg(node_p node, item_p item, hook_p lasthook)
718 {
719 	priv_p privp = NG_NODE_PRIVATE(node);
720 	struct ngpppoe_init_data *ourmsg = NULL;
721 	struct ng_mesg *resp = NULL;
722 	int error = 0;
723 	hook_p hook = NULL;
724 	sessp sp = NULL;
725 	negp neg = NULL;
726 	struct ng_mesg *msg;
727 
728 	NGI_GET_MSG(item, msg);
729 	CTR5(KTR_NET, "%20s: node [%x] (%p) got message %d with cookie %d",
730 	    __func__, node->nd_ID, node, msg->header.cmd,
731 	    msg->header.typecookie);
732 
733 	/* Deal with message according to cookie and command. */
734 	switch (msg->header.typecookie) {
735 	case NGM_PPPOE_COOKIE:
736 		switch (msg->header.cmd) {
737 		case NGM_PPPOE_CONNECT:
738 		case NGM_PPPOE_LISTEN:
739 		case NGM_PPPOE_OFFER:
740 		case NGM_PPPOE_SERVICE:
741 			ourmsg = (struct ngpppoe_init_data *)msg->data;
742 			if (msg->header.arglen < sizeof(*ourmsg)) {
743 				log(LOG_ERR, "ng_pppoe[%x]: init data too "
744 				    "small\n", node->nd_ID);
745 				LEAVE(EMSGSIZE);
746 			}
747 			if (msg->header.arglen - sizeof(*ourmsg) >
748 			    PPPOE_SERVICE_NAME_SIZE) {
749 				log(LOG_ERR, "ng_pppoe[%x]: service name "
750 				    "too big\n", node->nd_ID);
751 				LEAVE(EMSGSIZE);
752 			}
753 			if (msg->header.arglen - sizeof(*ourmsg) <
754 			    ourmsg->data_len) {
755 				log(LOG_ERR, "ng_pppoe[%x]: init data has bad "
756 				    "length, %d should be %zd\n", node->nd_ID,
757 				    ourmsg->data_len,
758 				    msg->header.arglen - sizeof (*ourmsg));
759 				LEAVE(EMSGSIZE);
760 			}
761 
762 			/* Make sure strcmp will terminate safely. */
763 			ourmsg->hook[sizeof(ourmsg->hook) - 1] = '\0';
764 
765 			/* Find hook by name. */
766 			hook = ng_findhook(node, ourmsg->hook);
767 			if (hook == NULL)
768 				LEAVE(ENOENT);
769 
770 			sp = NG_HOOK_PRIVATE(hook);
771 			if (sp == NULL)
772 				LEAVE(EINVAL);
773 
774 			if (msg->header.cmd == NGM_PPPOE_LISTEN) {
775 				/*
776 				 * Ensure we aren't already listening for this
777 				 * service.
778 				 */
779 				if (pppoe_find_svc(node, ourmsg->data,
780 				    ourmsg->data_len) != NULL)
781 					LEAVE(EEXIST);
782 			}
783 
784 			/*
785 			 * PPPOE_SERVICE advertisments are set up
786 			 * on sessions that are in PRIMED state.
787 			 */
788 			if (msg->header.cmd == NGM_PPPOE_SERVICE)
789 				break;
790 
791 			if (sp->state != PPPOE_SNONE) {
792 				log(LOG_NOTICE, "ng_pppoe[%x]: Session already "
793 				    "active\n", node->nd_ID);
794 				LEAVE(EISCONN);
795 			}
796 
797 			/*
798 			 * Set up prototype header.
799 			 */
800 			neg = malloc(sizeof(*neg), M_NETGRAPH_PPPOE,
801 			    M_NOWAIT | M_ZERO);
802 
803 			if (neg == NULL)
804 				LEAVE(ENOMEM);
805 
806 			neg->m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
807 			if (neg->m == NULL) {
808 				free(neg, M_NETGRAPH_PPPOE);
809 				LEAVE(ENOBUFS);
810 			}
811 			neg->m->m_pkthdr.rcvif = NULL;
812 			sp->neg = neg;
813 			ng_callout_init(&neg->handle);
814 			neg->m->m_len = sizeof(struct pppoe_full_hdr);
815 			neg->pkt = mtod(neg->m, union packet*);
816 			memcpy((void *)&neg->pkt->pkt_header.eh,
817 			    &privp->eh, sizeof(struct ether_header));
818 			neg->pkt->pkt_header.ph.ver = 0x1;
819 			neg->pkt->pkt_header.ph.type = 0x1;
820 			neg->pkt->pkt_header.ph.sid = 0x0000;
821 			neg->timeout = 0;
822 
823 			sp->creator = NGI_RETADDR(item);
824 		}
825 		switch (msg->header.cmd) {
826 		case NGM_PPPOE_GET_STATUS:
827 		    {
828 			struct ngpppoestat *stats;
829 
830 			NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT);
831 			if (!resp)
832 				LEAVE(ENOMEM);
833 
834 			stats = (struct ngpppoestat *) resp->data;
835 			stats->packets_in = privp->packets_in;
836 			stats->packets_out = privp->packets_out;
837 			break;
838 		    }
839 		case NGM_PPPOE_CONNECT:
840 		    {
841 			/*
842 			 * Check the hook exists and is Uninitialised.
843 			 * Send a PADI request, and start the timeout logic.
844 			 * Store the originator of this message so we can send
845 			 * a success of fail message to them later.
846 			 * Move the session to SINIT.
847 			 * Set up the session to the correct state and
848 			 * start it.
849 			 */
850 			int	i, acnlen = 0, acnsep = 0, srvlen;
851 			for (i = 0; i < ourmsg->data_len; i++) {
852 				if (ourmsg->data[i] == '\\') {
853 					acnlen = i;
854 					acnsep = 1;
855 					break;
856 				}
857 			}
858 			srvlen = ourmsg->data_len - acnlen - acnsep;
859 
860 			bcopy(ourmsg->data, neg->ac_name.data, acnlen);
861 			neg->ac_name_len = acnlen;
862 
863 			neg->service.hdr.tag_type = PTT_SRV_NAME;
864 			neg->service.hdr.tag_len = htons((uint16_t)srvlen);
865 			bcopy(ourmsg->data + acnlen + acnsep,
866 			    neg->service.data, srvlen);
867 			neg->service_len = srvlen;
868 			pppoe_start(sp);
869 			break;
870 		    }
871 		case NGM_PPPOE_LISTEN:
872 			/*
873 			 * Check the hook exists and is Uninitialised.
874 			 * Install the service matching string.
875 			 * Store the originator of this message so we can send
876 			 * a success of fail message to them later.
877 			 * Move the hook to 'LISTENING'
878 			 */
879 			neg->service.hdr.tag_type = PTT_SRV_NAME;
880 			neg->service.hdr.tag_len =
881 			    htons((uint16_t)ourmsg->data_len);
882 
883 			if (ourmsg->data_len)
884 				bcopy(ourmsg->data, neg->service.data,
885 				    ourmsg->data_len);
886 			neg->service_len = ourmsg->data_len;
887 			neg->pkt->pkt_header.ph.code = PADT_CODE;
888 			/*
889 			 * Wait for PADI packet coming from Ethernet.
890 			 */
891 			sp->state = PPPOE_LISTENING;
892 			LIST_INSERT_HEAD(&privp->listeners, sp, sessions);
893 			break;
894 		case NGM_PPPOE_OFFER:
895 			/*
896 			 * Check the hook exists and is Uninitialised.
897 			 * Store the originator of this message so we can send
898 			 * a success of fail message to them later.
899 			 * Store the AC-Name given and go to PRIMED.
900 			 */
901 			neg->ac_name.hdr.tag_type = PTT_AC_NAME;
902 			neg->ac_name.hdr.tag_len =
903 			    htons((uint16_t)ourmsg->data_len);
904 			if (ourmsg->data_len)
905 				bcopy(ourmsg->data, neg->ac_name.data,
906 				    ourmsg->data_len);
907 			neg->ac_name_len = ourmsg->data_len;
908 			neg->pkt->pkt_header.ph.code = PADO_CODE;
909 			/*
910 			 * Wait for PADI packet coming from hook.
911 			 */
912 			sp->state = PPPOE_PRIMED;
913 			break;
914 		case NGM_PPPOE_SERVICE:
915 			/*
916 			 * Check the session is primed.
917 			 * for now just allow ONE service to be advertised.
918 			 * If you do it twice you just overwrite.
919 			 */
920 			if (sp->state != PPPOE_PRIMED) {
921 				log(LOG_NOTICE, "ng_pppoe[%x]: session not "
922 				    "primed\n", node->nd_ID);
923 				LEAVE(EISCONN);
924 			}
925 			neg = sp->neg;
926 			neg->service.hdr.tag_type = PTT_SRV_NAME;
927 			neg->service.hdr.tag_len =
928 			    htons((uint16_t)ourmsg->data_len);
929 
930 			if (ourmsg->data_len)
931 				bcopy(ourmsg->data, neg->service.data,
932 				    ourmsg->data_len);
933 			neg->service_len = ourmsg->data_len;
934 			break;
935 		case NGM_PPPOE_SETMODE:
936 		    {
937 			char *s;
938 			size_t len;
939 
940 			if (msg->header.arglen == 0)
941 				LEAVE(EINVAL);
942 
943 			s = (char *)msg->data;
944 			len = msg->header.arglen - 1;
945 
946 			/* Search for matching mode string. */
947 			if (len == strlen(NG_PPPOE_STANDARD) &&
948 			    (strncmp(NG_PPPOE_STANDARD, s, len) == 0)) {
949 				privp->flags = 0;
950 				privp->eh.ether_type = ETHERTYPE_PPPOE_DISC;
951 				break;
952 			}
953 			if (len == strlen(NG_PPPOE_3COM) &&
954 			    (strncmp(NG_PPPOE_3COM, s, len) == 0)) {
955 				privp->flags |= COMPAT_3COM;
956 				privp->eh.ether_type =
957 				    ETHERTYPE_PPPOE_3COM_DISC;
958 				break;
959 			}
960 			if (len == strlen(NG_PPPOE_DLINK) &&
961 			    (strncmp(NG_PPPOE_DLINK, s, len) == 0)) {
962 				privp->flags |= COMPAT_DLINK;
963 				break;
964 			}
965 			error = EINVAL;
966 			break;
967 		    }
968 		case NGM_PPPOE_GETMODE:
969 		    {
970 			char *s;
971 			size_t len = 0;
972 
973 			if (privp->flags == 0)
974 				len += strlen(NG_PPPOE_STANDARD) + 1;
975 			if (privp->flags & COMPAT_3COM)
976 				len += strlen(NG_PPPOE_3COM) + 1;
977 			if (privp->flags & COMPAT_DLINK)
978 				len += strlen(NG_PPPOE_DLINK) + 1;
979 
980 			NG_MKRESPONSE(resp, msg, len, M_NOWAIT);
981 			if (resp == NULL)
982 				LEAVE(ENOMEM);
983 
984 			s = (char *)resp->data;
985 			if (privp->flags == 0) {
986 				len = strlen(NG_PPPOE_STANDARD);
987 				strlcpy(s, NG_PPPOE_STANDARD, len + 1);
988 				break;
989 			}
990 			if (privp->flags & COMPAT_3COM) {
991 				len = strlen(NG_PPPOE_3COM);
992 				strlcpy(s, NG_PPPOE_3COM, len + 1);
993 				s += len;
994 			}
995 			if (privp->flags & COMPAT_DLINK) {
996 				if (s != resp->data)
997 					*s++ = '|';
998 				len = strlen(NG_PPPOE_DLINK);
999 				strlcpy(s, NG_PPPOE_DLINK, len + 1);
1000 			}
1001 			break;
1002 		    }
1003 		case NGM_PPPOE_SETENADDR:
1004 			if (msg->header.arglen != ETHER_ADDR_LEN)
1005 				LEAVE(EINVAL);
1006 			bcopy(msg->data, &privp->eh.ether_shost,
1007 			    ETHER_ADDR_LEN);
1008 			break;
1009 		default:
1010 			LEAVE(EINVAL);
1011 		}
1012 		break;
1013 	case NGM_ETHER_COOKIE:
1014 		if (!(msg->header.flags & NGF_RESP))
1015 			LEAVE(EINVAL);
1016 		switch (msg->header.cmd) {
1017 		case NGM_ETHER_GET_ENADDR:
1018 			if (msg->header.arglen != ETHER_ADDR_LEN)
1019 				LEAVE(EINVAL);
1020 			bcopy(msg->data, &privp->eh.ether_shost,
1021 			    ETHER_ADDR_LEN);
1022 			break;
1023 		default:
1024 			LEAVE(EINVAL);
1025 		}
1026 		break;
1027 	default:
1028 		LEAVE(EINVAL);
1029 	}
1030 
1031 	/* Take care of synchronous response, if any. */
1032 quit:
1033 	CTR2(KTR_NET, "%20s: returning %d", __func__, error);
1034 	NG_RESPOND_MSG(error, node, item, resp);
1035 	/* Free the message and return. */
1036 	NG_FREE_MSG(msg);
1037 	return(error);
1038 }
1039 
1040 /*
1041  * Start a client into the first state. A separate function because
1042  * it can be needed if the negotiation times out.
1043  */
1044 static void
1045 pppoe_start(sessp sp)
1046 {
1047 	hook_p	hook = sp->hook;
1048 	node_p	node = NG_HOOK_NODE(hook);
1049 	priv_p	privp = NG_NODE_PRIVATE(node);
1050 	negp	neg = sp->neg;
1051 	struct {
1052 		struct pppoe_tag hdr;
1053 		union	uniq	data;
1054 	} __packed uniqtag;
1055 	struct  mbuf *m0;
1056 	int	error;
1057 
1058 	/*
1059 	 * Kick the state machine into starting up.
1060 	 */
1061 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1062 	sp->state = PPPOE_SINIT;
1063 	/*
1064 	 * Reset the packet header to broadcast. Since we are
1065 	 * in a client mode use configured ethertype.
1066 	 */
1067 	memcpy((void *)&neg->pkt->pkt_header.eh, &privp->eh,
1068 	    sizeof(struct ether_header));
1069 	neg->pkt->pkt_header.ph.code = PADI_CODE;
1070 	uniqtag.hdr.tag_type = PTT_HOST_UNIQ;
1071 	uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(uniqtag.data));
1072 	uniqtag.data.pointer = sp;
1073 	init_tags(sp);
1074 	insert_tag(sp, &uniqtag.hdr);
1075 	insert_tag(sp, &neg->service.hdr);
1076 	make_packet(sp);
1077 	/*
1078 	 * Send packet and prepare to retransmit it after timeout.
1079 	 */
1080 	ng_callout(&neg->handle, node, hook, PPPOE_INITIAL_TIMEOUT * hz,
1081 	    pppoe_ticker, NULL, 0);
1082 	neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1083 	m0 = m_copypacket(neg->m, M_DONTWAIT);
1084 	NG_SEND_DATA_ONLY(error, privp->ethernet_hook, m0);
1085 }
1086 
1087 static int
1088 send_acname(sessp sp, const struct pppoe_tag *tag)
1089 {
1090 	int error, tlen;
1091 	struct ng_mesg *msg;
1092 	struct ngpppoe_sts *sts;
1093 
1094 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1095 
1096 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_ACNAME,
1097 	    sizeof(struct ngpppoe_sts), M_NOWAIT);
1098 	if (msg == NULL)
1099 		return (ENOMEM);
1100 
1101 	sts = (struct ngpppoe_sts *)msg->data;
1102 	tlen = min(NG_HOOKSIZ - 1, ntohs(tag->tag_len));
1103 	strncpy(sts->hook, tag->tag_data, tlen);
1104 	sts->hook[tlen] = '\0';
1105 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1106 
1107 	return (error);
1108 }
1109 
1110 static int
1111 send_sessionid(sessp sp)
1112 {
1113 	int error;
1114 	struct ng_mesg *msg;
1115 
1116 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1117 
1118 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SESSIONID,
1119 	    sizeof(uint16_t), M_NOWAIT);
1120 	if (msg == NULL)
1121 		return (ENOMEM);
1122 
1123 	*(uint16_t *)msg->data = sp->Session_ID;
1124 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1125 
1126 	return (error);
1127 }
1128 
1129 /*
1130  * Receive data from session hook and do something with it.
1131  */
1132 static int
1133 ng_pppoe_rcvdata(hook_p hook, item_p item)
1134 {
1135 	node_p			node = NG_HOOK_NODE(hook);
1136 	const priv_p		privp = NG_NODE_PRIVATE(node);
1137 	sessp			sp = NG_HOOK_PRIVATE(hook);
1138 	struct pppoe_full_hdr	*wh;
1139 	struct mbuf		*m;
1140 	int			error;
1141 
1142 	CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1143 	    __func__, node->nd_ID, node, item, hook->hk_name, hook);
1144 
1145 	NGI_GET_M(item, m);
1146 	switch (sp->state) {
1147 	case	PPPOE_NEWCONNECTED:
1148 	case	PPPOE_CONNECTED: {
1149 		/*
1150 		 * Remove PPP address and control fields, if any.
1151 		 * For example, ng_ppp(4) always sends LCP packets
1152 		 * with address and control fields as required by
1153 		 * generic PPP. PPPoE is an exception to the rule.
1154 		 */
1155 		if (m->m_pkthdr.len >= 2) {
1156 			if (m->m_len < 2 && !(m = m_pullup(m, 2)))
1157 				LEAVE(ENOBUFS);
1158 			if (mtod(m, u_char *)[0] == 0xff &&
1159 			    mtod(m, u_char *)[1] == 0x03)
1160 				m_adj(m, 2);
1161 		}
1162 		/*
1163 		 * Bang in a pre-made header, and set the length up
1164 		 * to be correct. Then send it to the ethernet driver.
1165 		 */
1166 		M_PREPEND(m, sizeof(*wh), M_DONTWAIT);
1167 		if (m == NULL)
1168 			LEAVE(ENOBUFS);
1169 
1170 		wh = mtod(m, struct pppoe_full_hdr *);
1171 		bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1172 		wh->ph.length = htons(m->m_pkthdr.len - sizeof(*wh));
1173 		NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m);
1174 		privp->packets_out++;
1175 		break;
1176 		}
1177 	case	PPPOE_PRIMED: {
1178 		struct {
1179 			struct pppoe_tag hdr;
1180 			union	uniq	data;
1181 		} __packed 	uniqtag;
1182 		const struct pppoe_tag	*tag;
1183 		struct mbuf 	*m0;
1184 		const struct pppoe_hdr	*ph;
1185 		negp		neg = sp->neg;
1186 	        uint16_t	session;
1187 		uint16_t	length;
1188 		uint8_t		code;
1189 
1190 		/*
1191 		 * A PADI packet is being returned by the application
1192 		 * that has set up this hook. This indicates that it
1193 		 * wants us to offer service.
1194 		 */
1195 		if (m->m_len < sizeof(*wh)) {
1196 			m = m_pullup(m, sizeof(*wh));
1197 			if (m == NULL)
1198 				LEAVE(ENOBUFS);
1199 		}
1200 		wh = mtod(m, struct pppoe_full_hdr *);
1201 		ph = &wh->ph;
1202 		session = ntohs(wh->ph.sid);
1203 		length = ntohs(wh->ph.length);
1204 		code = wh->ph.code;
1205 		/* Use peers mode in session. */
1206 		neg->pkt->pkt_header.eh.ether_type = wh->eh.ether_type;
1207 		if (code != PADI_CODE)
1208 			LEAVE(EINVAL);
1209 		ng_uncallout(&neg->handle, node);
1210 
1211 		/*
1212 		 * This is the first time we hear
1213 		 * from the client, so note it's
1214 		 * unicast address, replacing the
1215 		 * broadcast address.
1216 		 */
1217 		bcopy(wh->eh.ether_shost,
1218 			neg->pkt->pkt_header.eh.ether_dhost,
1219 			ETHER_ADDR_LEN);
1220 		sp->state = PPPOE_SOFFER;
1221 		neg->timeout = 0;
1222 		neg->pkt->pkt_header.ph.code = PADO_CODE;
1223 
1224 		/*
1225 		 * Start working out the tags to respond with.
1226 		 */
1227 		uniqtag.hdr.tag_type = PTT_AC_COOKIE;
1228 		uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(sp));
1229 		uniqtag.data.pointer = sp;
1230 		init_tags(sp);
1231 		insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1232 		if ((tag = get_tag(ph, PTT_SRV_NAME)))
1233 			insert_tag(sp, tag);	  /* return service */
1234 		/*
1235 		 * If we have a NULL service request
1236 		 * and have an extra service defined in this hook,
1237 		 * then also add a tag for the extra service.
1238 		 * XXX this is a hack. eventually we should be able
1239 		 * to support advertising many services, not just one
1240 		 */
1241 		if (((tag == NULL) || (tag->tag_len == 0)) &&
1242 		    (neg->service.hdr.tag_len != 0)) {
1243 			insert_tag(sp, &neg->service.hdr); /* SERVICE */
1244 		}
1245 		if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1246 			insert_tag(sp, tag); /* returned hostunique */
1247 		insert_tag(sp, &uniqtag.hdr);
1248 		scan_tags(sp, ph);
1249 		make_packet(sp);
1250 		/*
1251 		 * Send the offer but if they don't respond
1252 		 * in PPPOE_OFFER_TIMEOUT seconds, forget about it.
1253 		 */
1254 		ng_callout(&neg->handle, node, hook, PPPOE_OFFER_TIMEOUT * hz,
1255 		    pppoe_ticker, NULL, 0);
1256 		m0 = m_copypacket(sp->neg->m, M_DONTWAIT);
1257 		NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1258 		privp->packets_out++;
1259 		break;
1260 		}
1261 
1262 	/*
1263 	 * Packets coming from the hook make no sense
1264 	 * to sessions in the rest of states. Throw them away.
1265 	 */
1266 	default:
1267 		LEAVE(ENETUNREACH);
1268 	}
1269 quit:
1270 	if (item)
1271 		NG_FREE_ITEM(item);
1272 	NG_FREE_M(m);
1273 	return (error);
1274 }
1275 
1276 /*
1277  * Receive data from ether and do something with it.
1278  */
1279 static int
1280 ng_pppoe_rcvdata_ether(hook_p hook, item_p item)
1281 {
1282 	node_p			node = NG_HOOK_NODE(hook);
1283 	const priv_p		privp = NG_NODE_PRIVATE(node);
1284 	sessp			sp = NG_HOOK_PRIVATE(hook);
1285 	const struct pppoe_tag	*utag = NULL, *tag = NULL;
1286 	const struct pppoe_full_hdr *wh;
1287 	const struct pppoe_hdr	*ph;
1288 	negp			neg = NULL;
1289 	struct mbuf		*m;
1290 	hook_p 			sendhook;
1291 	int			error = 0;
1292 	uint16_t		session;
1293 	uint16_t		length;
1294 	uint8_t			code;
1295 	struct	mbuf 		*m0;
1296 
1297 	CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1298 	    __func__, node->nd_ID, node, item, hook->hk_name, hook);
1299 
1300 	NGI_GET_M(item, m);
1301 	/*
1302 	 * Dig out various fields from the packet.
1303 	 * Use them to decide where to send it.
1304 	 */
1305 	privp->packets_in++;
1306 	if( m->m_len < sizeof(*wh)) {
1307 		m = m_pullup(m, sizeof(*wh)); /* Checks length */
1308 		if (m == NULL) {
1309 			log(LOG_NOTICE, "ng_pppoe[%x]: couldn't "
1310 			    "m_pullup(wh)\n", node->nd_ID);
1311 			LEAVE(ENOBUFS);
1312 		}
1313 	}
1314 	wh = mtod(m, struct pppoe_full_hdr *);
1315 	length = ntohs(wh->ph.length);
1316 	switch(wh->eh.ether_type) {
1317 	case	ETHERTYPE_PPPOE_3COM_DISC: /* fall through */
1318 	case	ETHERTYPE_PPPOE_DISC:
1319 		/*
1320 		 * We need to try to make sure that the tag area
1321 		 * is contiguous, or we could wander off the end
1322 		 * of a buffer and make a mess.
1323 		 * (Linux wouldn't have this problem).
1324 		 */
1325 		if (m->m_pkthdr.len <= MHLEN) {
1326 			if( m->m_len < m->m_pkthdr.len) {
1327 				m = m_pullup(m, m->m_pkthdr.len);
1328 				if (m == NULL) {
1329 					log(LOG_NOTICE, "ng_pppoe[%x]: "
1330 					    "couldn't m_pullup(pkthdr)\n",
1331 					    node->nd_ID);
1332 					LEAVE(ENOBUFS);
1333 				}
1334 			}
1335 		}
1336 		if (m->m_len != m->m_pkthdr.len) {
1337 			/*
1338 			 * It's not all in one piece.
1339 			 * We need to do extra work.
1340 			 * Put it into a cluster.
1341 			 */
1342 			struct mbuf *n;
1343 			n = m_dup(m, M_DONTWAIT);
1344 			m_freem(m);
1345 			m = n;
1346 			if (m) {
1347 				/* just check we got a cluster */
1348 				if (m->m_len != m->m_pkthdr.len) {
1349 					m_freem(m);
1350 					m = NULL;
1351 				}
1352 			}
1353 			if (m == NULL) {
1354 				log(LOG_NOTICE, "ng_pppoe[%x]: packet "
1355 				    "fragmented\n", node->nd_ID);
1356 				LEAVE(EMSGSIZE);
1357 			}
1358 		}
1359 		wh = mtod(m, struct pppoe_full_hdr *);
1360 		length = ntohs(wh->ph.length);
1361 		ph = &wh->ph;
1362 		session = ntohs(wh->ph.sid);
1363 		code = wh->ph.code;
1364 
1365 		switch(code) {
1366 		case	PADI_CODE:
1367 			/*
1368 			 * We are a server:
1369 			 * Look for a hook with the required service and send
1370 			 * the ENTIRE packet up there. It should come back to
1371 			 * a new hook in PRIMED state. Look there for further
1372 			 * processing.
1373 			 */
1374 			tag = get_tag(ph, PTT_SRV_NAME);
1375 			if (tag == NULL) {
1376 				CTR1(KTR_NET, "%20s: PADI w/o Service-Name",
1377 				    __func__);
1378 				LEAVE(ENETUNREACH);
1379 			}
1380 
1381 			/*
1382 			 * First, try to match Service-Name against our
1383 			 * listening hooks. If no success and we are in D-Link
1384 			 * compat mode and Service-Name is empty, then we
1385 			 * broadcast the PADI to all listening hooks.
1386 			 */
1387 			sendhook = pppoe_match_svc(node, tag);
1388 			if (sendhook != NULL)
1389 				NG_FWD_NEW_DATA(error, item, sendhook, m);
1390 			else if (privp->flags & COMPAT_DLINK &&
1391 				 ntohs(tag->tag_len) == 0)
1392 				error = pppoe_broadcast_padi(node, m);
1393 			else
1394 				error = ENETUNREACH;
1395 			break;
1396 		case	PADO_CODE:
1397 			/*
1398 			 * We are a client:
1399 			 * Use the host_uniq tag to find the hook this is in
1400 			 * response to. Received #2, now send #3
1401 			 * For now simply accept the first we receive.
1402 			 */
1403 			utag = get_tag(ph, PTT_HOST_UNIQ);
1404 			if ((utag == NULL) ||
1405 			    (ntohs(utag->tag_len) != sizeof(sp))) {
1406 				log(LOG_NOTICE, "ng_pppoe[%x]: no host "
1407 				    "unique field\n", node->nd_ID);
1408 				LEAVE(ENETUNREACH);
1409 			}
1410 
1411 			sendhook = pppoe_finduniq(node, utag);
1412 			if (sendhook == NULL) {
1413 				log(LOG_NOTICE, "ng_pppoe[%x]: no "
1414 				    "matching session\n", node->nd_ID);
1415 				LEAVE(ENETUNREACH);
1416 			}
1417 
1418 			/*
1419 			 * Check the session is in the right state.
1420 			 * It needs to be in PPPOE_SINIT.
1421 			 */
1422 			sp = NG_HOOK_PRIVATE(sendhook);
1423 			if (sp->state == PPPOE_SREQ ||
1424 			    sp->state == PPPOE_CONNECTED) {
1425 				break;	/* Multiple PADO is OK. */
1426 			}
1427 			if (sp->state != PPPOE_SINIT) {
1428 				log(LOG_NOTICE, "ng_pppoe[%x]: session "
1429 				    "in wrong state\n", node->nd_ID);
1430 				LEAVE(ENETUNREACH);
1431 			}
1432 			neg = sp->neg;
1433 			/* If requested specific AC-name, check it. */
1434 			if (neg->ac_name_len) {
1435 				tag = get_tag(ph, PTT_AC_NAME);
1436 				if (!tag) {
1437 					/* No PTT_AC_NAME in PADO */
1438 					break;
1439 				}
1440 				if (neg->ac_name_len != htons(tag->tag_len) ||
1441 				    strncmp(neg->ac_name.data, tag->tag_data,
1442 				    neg->ac_name_len) != 0) {
1443 					break;
1444 				}
1445 			}
1446 			sp->state = PPPOE_SREQ;
1447 			ng_uncallout(&neg->handle, node);
1448 
1449 			/*
1450 			 * This is the first time we hear
1451 			 * from the server, so note it's
1452 			 * unicast address, replacing the
1453 			 * broadcast address .
1454 			 */
1455 			bcopy(wh->eh.ether_shost,
1456 				neg->pkt->pkt_header.eh.ether_dhost,
1457 				ETHER_ADDR_LEN);
1458 			neg->timeout = 0;
1459 			neg->pkt->pkt_header.ph.code = PADR_CODE;
1460 			init_tags(sp);
1461 			insert_tag(sp, utag);      	/* Host Unique */
1462 			if ((tag = get_tag(ph, PTT_AC_COOKIE)))
1463 				insert_tag(sp, tag); 	/* return cookie */
1464 			if ((tag = get_tag(ph, PTT_AC_NAME))) {
1465 				insert_tag(sp, tag); 	/* return it */
1466 				send_acname(sp, tag);
1467 			}
1468 			insert_tag(sp, &neg->service.hdr); /* Service */
1469 			scan_tags(sp, ph);
1470 			make_packet(sp);
1471 			sp->state = PPPOE_SREQ;
1472 			ng_callout(&neg->handle, node, sp->hook,
1473 			    PPPOE_INITIAL_TIMEOUT * hz,
1474 			    pppoe_ticker, NULL, 0);
1475 			neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1476 			m0 = m_copypacket(neg->m, M_DONTWAIT);
1477 			NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1478 			break;
1479 		case	PADR_CODE:
1480 			/*
1481 			 * We are a server:
1482 			 * Use the ac_cookie tag to find the
1483 			 * hook this is in response to.
1484 			 */
1485 			utag = get_tag(ph, PTT_AC_COOKIE);
1486 			if ((utag == NULL) ||
1487 			    (ntohs(utag->tag_len) != sizeof(sp))) {
1488 				LEAVE(ENETUNREACH);
1489 			}
1490 
1491 			sendhook = pppoe_finduniq(node, utag);
1492 			if (sendhook == NULL)
1493 				LEAVE(ENETUNREACH);
1494 
1495 			/*
1496 			 * Check the session is in the right state.
1497 			 * It needs to be in PPPOE_SOFFER or PPPOE_NEWCONNECTED.
1498 			 * If the latter, then this is a retry by the client,
1499 			 * so be nice, and resend.
1500 			 */
1501 			sp = NG_HOOK_PRIVATE(sendhook);
1502 			if (sp->state == PPPOE_NEWCONNECTED) {
1503 				/*
1504 				 * Whoa! drop back to resend that PADS packet.
1505 				 * We should still have a copy of it.
1506 				 */
1507 				sp->state = PPPOE_SOFFER;
1508 			} else if (sp->state != PPPOE_SOFFER)
1509 				LEAVE (ENETUNREACH);
1510 			neg = sp->neg;
1511 			ng_uncallout(&neg->handle, node);
1512 			neg->pkt->pkt_header.ph.code = PADS_CODE;
1513 			if (sp->Session_ID == 0) {
1514 				neg->pkt->pkt_header.ph.sid =
1515 				    htons(pppoe_getnewsession(sp));
1516 			}
1517 			send_sessionid(sp);
1518 			neg->timeout = 0;
1519 			/*
1520 			 * start working out the tags to respond with.
1521 			 */
1522 			init_tags(sp);
1523 			insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1524 			if ((tag = get_tag(ph, PTT_SRV_NAME)))
1525 				insert_tag(sp, tag);/* return service */
1526 			if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1527 				insert_tag(sp, tag); /* return it */
1528 			insert_tag(sp, utag);	/* ac_cookie */
1529 			scan_tags(sp, ph);
1530 			make_packet(sp);
1531 			sp->state = PPPOE_NEWCONNECTED;
1532 
1533 			/* Send the PADS without a timeout - we're now connected. */
1534 			m0 = m_copypacket(sp->neg->m, M_DONTWAIT);
1535 			NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1536 
1537 			/*
1538 			 * Having sent the last Negotiation header,
1539 			 * Set up the stored packet header to be correct for
1540 			 * the actual session. But keep the negotialtion stuff
1541 			 * around in case we need to resend this last packet.
1542 			 * We'll discard it when we move from NEWCONNECTED
1543 			 * to CONNECTED
1544 			 */
1545 			sp->pkt_hdr = neg->pkt->pkt_header;
1546 			/* Configure ethertype depending on what
1547 			 * ethertype was used at discovery phase */
1548 			if (sp->pkt_hdr.eh.ether_type ==
1549 			    ETHERTYPE_PPPOE_3COM_DISC)
1550 				sp->pkt_hdr.eh.ether_type
1551 					= ETHERTYPE_PPPOE_3COM_SESS;
1552 			else
1553 				sp->pkt_hdr.eh.ether_type
1554 					= ETHERTYPE_PPPOE_SESS;
1555 			sp->pkt_hdr.ph.code = 0;
1556 			pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1557 			break;
1558 		case	PADS_CODE:
1559 			/*
1560 			 * We are a client:
1561 			 * Use the host_uniq tag to find the hook this is in
1562 			 * response to. Take the session ID and store it away.
1563 			 * Also make sure the pre-made header is correct and
1564 			 * set us into Session mode.
1565 			 */
1566 			utag = get_tag(ph, PTT_HOST_UNIQ);
1567 			if ((utag == NULL) ||
1568 			    (ntohs(utag->tag_len) != sizeof(sp))) {
1569 				LEAVE (ENETUNREACH);
1570 			}
1571 			sendhook = pppoe_finduniq(node, utag);
1572 			if (sendhook == NULL)
1573 				LEAVE(ENETUNREACH);
1574 
1575 			/*
1576 			 * Check the session is in the right state.
1577 			 * It needs to be in PPPOE_SREQ.
1578 			 */
1579 			sp = NG_HOOK_PRIVATE(sendhook);
1580 			if (sp->state != PPPOE_SREQ)
1581 				LEAVE(ENETUNREACH);
1582 			neg = sp->neg;
1583 			ng_uncallout(&neg->handle, node);
1584 			neg->pkt->pkt_header.ph.sid = wh->ph.sid;
1585 			sp->Session_ID = ntohs(wh->ph.sid);
1586 			pppoe_addsession(sp);
1587 			send_sessionid(sp);
1588 			neg->timeout = 0;
1589 			sp->state = PPPOE_CONNECTED;
1590 			/*
1591 			 * Now we have gone to Connected mode,
1592 			 * Free all resources needed for negotiation.
1593 			 * Keep a copy of the header we will be using.
1594 			 */
1595 			sp->pkt_hdr = neg->pkt->pkt_header;
1596 			if (privp->flags & COMPAT_3COM)
1597 				sp->pkt_hdr.eh.ether_type
1598 					= ETHERTYPE_PPPOE_3COM_SESS;
1599 			else
1600 				sp->pkt_hdr.eh.ether_type
1601 					= ETHERTYPE_PPPOE_SESS;
1602 			sp->pkt_hdr.ph.code = 0;
1603 			m_freem(neg->m);
1604 			free(sp->neg, M_NETGRAPH_PPPOE);
1605 			sp->neg = NULL;
1606 			pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1607 			break;
1608 		case	PADT_CODE:
1609 			/*
1610 			 * Find matching peer/session combination.
1611 			 */
1612 			sp = pppoe_findsession(privp, wh);
1613 			if (sp == NULL)
1614 				LEAVE(ENETUNREACH);
1615 			/* Disconnect that hook. */
1616 			ng_rmhook_self(sp->hook);
1617 			break;
1618 		default:
1619 			LEAVE(EPFNOSUPPORT);
1620 		}
1621 		break;
1622 	case	ETHERTYPE_PPPOE_3COM_SESS:
1623 	case	ETHERTYPE_PPPOE_SESS:
1624 		/*
1625 		 * Find matching peer/session combination.
1626 		 */
1627 		sp = pppoe_findsession(privp, wh);
1628 		if (sp == NULL)
1629 			LEAVE (ENETUNREACH);
1630 		m_adj(m, sizeof(*wh));
1631 
1632 		/* If packet too short, dump it. */
1633 		if (m->m_pkthdr.len < length)
1634 			LEAVE(EMSGSIZE);
1635 		/* Also need to trim excess at the end */
1636 		if (m->m_pkthdr.len > length) {
1637 			m_adj(m, -((int)(m->m_pkthdr.len - length)));
1638 		}
1639 		if ( sp->state != PPPOE_CONNECTED) {
1640 			if (sp->state == PPPOE_NEWCONNECTED) {
1641 				sp->state = PPPOE_CONNECTED;
1642 				/*
1643 				 * Now we have gone to Connected mode,
1644 				 * Free all resources needed for negotiation.
1645 				 * Be paranoid about whether there may be
1646 				 * a timeout.
1647 				 */
1648 				m_freem(sp->neg->m);
1649 				ng_uncallout(&sp->neg->handle, node);
1650 				free(sp->neg, M_NETGRAPH_PPPOE);
1651 				sp->neg = NULL;
1652 			} else {
1653 				LEAVE (ENETUNREACH);
1654 			}
1655 		}
1656 		NG_FWD_NEW_DATA(error, item, sp->hook, m);
1657 		break;
1658 	default:
1659 		LEAVE(EPFNOSUPPORT);
1660 	}
1661 quit:
1662 	if (item)
1663 		NG_FREE_ITEM(item);
1664 	NG_FREE_M(m);
1665 	return (error);
1666 }
1667 
1668 /*
1669  * Receive data from debug hook and bypass it to ether.
1670  */
1671 static int
1672 ng_pppoe_rcvdata_debug(hook_p hook, item_p item)
1673 {
1674 	node_p		node = NG_HOOK_NODE(hook);
1675 	const priv_p	privp = NG_NODE_PRIVATE(node);
1676 	int		error;
1677 
1678 	CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1679 	    __func__, node->nd_ID, node, item, hook->hk_name, hook);
1680 
1681 	NG_FWD_ITEM_HOOK(error, item, privp->ethernet_hook);
1682 	privp->packets_out++;
1683 	return (error);
1684 }
1685 
1686 /*
1687  * Do local shutdown processing..
1688  * If we are a persistant device, we might refuse to go away, and
1689  * we'd only remove our links and reset ourself.
1690  */
1691 static int
1692 ng_pppoe_shutdown(node_p node)
1693 {
1694 	const priv_p privp = NG_NODE_PRIVATE(node);
1695 	int	i;
1696 
1697 	for (i = 0; i < SESSHASHSIZE; i++)
1698 	    mtx_destroy(&privp->sesshash[i].mtx);
1699 	NG_NODE_SET_PRIVATE(node, NULL);
1700 	NG_NODE_UNREF(privp->node);
1701 	free(privp, M_NETGRAPH_PPPOE);
1702 	return (0);
1703 }
1704 
1705 /*
1706  * Hook disconnection
1707  *
1708  * Clean up all dangling links and information about the session/hook.
1709  * For this type, removal of the last link destroys the node.
1710  */
1711 static int
1712 ng_pppoe_disconnect(hook_p hook)
1713 {
1714 	node_p node = NG_HOOK_NODE(hook);
1715 	priv_p privp = NG_NODE_PRIVATE(node);
1716 	sessp	sp;
1717 
1718 	if (hook == privp->debug_hook) {
1719 		privp->debug_hook = NULL;
1720 	} else if (hook == privp->ethernet_hook) {
1721 		privp->ethernet_hook = NULL;
1722 		if (NG_NODE_IS_VALID(node))
1723 			ng_rmnode_self(node);
1724 	} else {
1725 		sp = NG_HOOK_PRIVATE(hook);
1726 		if (sp->state != PPPOE_SNONE ) {
1727 			pppoe_send_event(sp, NGM_PPPOE_CLOSE);
1728 		}
1729 		/*
1730 		 * According to the spec, if we are connected,
1731 		 * we should send a DISC packet if we are shutting down
1732 		 * a session.
1733 		 */
1734 		if ((privp->ethernet_hook)
1735 		&& ((sp->state == PPPOE_CONNECTED)
1736 		 || (sp->state == PPPOE_NEWCONNECTED))) {
1737 			struct mbuf *m;
1738 
1739 			/* Generate a packet of that type. */
1740 			MGETHDR(m, M_DONTWAIT, MT_DATA);
1741 			if (m == NULL)
1742 				log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
1743 				    "mbufs\n", node->nd_ID);
1744 			else {
1745 				struct pppoe_full_hdr *wh;
1746 				struct pppoe_tag *tag;
1747 				int	msglen = strlen(SIGNOFF);
1748 				int	error = 0;
1749 
1750 				m->m_pkthdr.rcvif = NULL;
1751 				m->m_pkthdr.len = m->m_len = sizeof(*wh);
1752 				wh = mtod(m, struct pppoe_full_hdr *);
1753 				bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1754 
1755 				/* Revert the stored header to DISC/PADT mode. */
1756 				wh->ph.code = PADT_CODE;
1757 				/*
1758 				 * Configure ethertype depending on what
1759 				 * was used during sessions stage.
1760 				 */
1761 				if (wh->eh.ether_type ==
1762 				    ETHERTYPE_PPPOE_3COM_SESS)
1763 					wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
1764 				else
1765 					wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1766 				/*
1767 				 * Add a General error message and adjust
1768 				 * sizes.
1769 				 */
1770 				tag = wh->ph.tag;
1771 				tag->tag_type = PTT_GEN_ERR;
1772 				tag->tag_len = htons((u_int16_t)msglen);
1773 				strncpy(tag->tag_data, SIGNOFF, msglen);
1774 				m->m_pkthdr.len = (m->m_len += sizeof(*tag) +
1775 				    msglen);
1776 				wh->ph.length = htons(sizeof(*tag) + msglen);
1777 				NG_SEND_DATA_ONLY(error,
1778 					privp->ethernet_hook, m);
1779 			}
1780 		}
1781 		if (sp->state == PPPOE_LISTENING)
1782 			LIST_REMOVE(sp, sessions);
1783 		else if (sp->Session_ID)
1784 			pppoe_delsession(sp);
1785 		/*
1786 		 * As long as we have somewhere to store the timeout handle,
1787 		 * we may have a timeout pending.. get rid of it.
1788 		 */
1789 		if (sp->neg) {
1790 			ng_uncallout(&sp->neg->handle, node);
1791 			if (sp->neg->m)
1792 				m_freem(sp->neg->m);
1793 			free(sp->neg, M_NETGRAPH_PPPOE);
1794 		}
1795 		free(sp, M_NETGRAPH_PPPOE);
1796 		NG_HOOK_SET_PRIVATE(hook, NULL);
1797 	}
1798 	if ((NG_NODE_NUMHOOKS(node) == 0) &&
1799 	    (NG_NODE_IS_VALID(node)))
1800 		ng_rmnode_self(node);
1801 	return (0);
1802 }
1803 
1804 /*
1805  * Timeouts come here.
1806  */
1807 static void
1808 pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2)
1809 {
1810 	priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
1811 	sessp	sp = NG_HOOK_PRIVATE(hook);
1812 	negp	neg = sp->neg;
1813 	struct mbuf *m0 = NULL;
1814 	int	error = 0;
1815 
1816 	CTR6(KTR_NET, "%20s: node [%x] (%p) hook \"%s\" (%p) session %d",
1817 	    __func__, node->nd_ID, node, hook->hk_name, hook, sp->Session_ID);
1818 	switch(sp->state) {
1819 		/*
1820 		 * Resend the last packet, using an exponential backoff.
1821 		 * After a period of time, stop growing the backoff,
1822 		 * And either leave it, or revert to the start.
1823 		 */
1824 	case	PPPOE_SINIT:
1825 	case	PPPOE_SREQ:
1826 		/* Timeouts on these produce resends. */
1827 		m0 = m_copypacket(sp->neg->m, M_DONTWAIT);
1828 		NG_SEND_DATA_ONLY( error, privp->ethernet_hook, m0);
1829 		ng_callout(&neg->handle, node, hook, neg->timeout * hz,
1830 		    pppoe_ticker, NULL, 0);
1831 		if ((neg->timeout <<= 1) > PPPOE_TIMEOUT_LIMIT) {
1832 			if (sp->state == PPPOE_SREQ) {
1833 				/* Revert to SINIT mode. */
1834 				pppoe_start(sp);
1835 			} else {
1836 				neg->timeout = PPPOE_TIMEOUT_LIMIT;
1837 			}
1838 		}
1839 		break;
1840 	case	PPPOE_PRIMED:
1841 	case	PPPOE_SOFFER:
1842 		/* A timeout on these says "give up" */
1843 		ng_rmhook_self(hook);
1844 		break;
1845 	default:
1846 		/* Timeouts have no meaning in other states. */
1847 		log(LOG_NOTICE, "ng_pppoe[%x]: unexpected timeout\n",
1848 		    node->nd_ID);
1849 	}
1850 }
1851 
1852 /*
1853  * Parse an incoming packet to see if any tags should be copied to the
1854  * output packet. Don't do any tags that have been handled in the main
1855  * state machine.
1856  */
1857 static const struct pppoe_tag*
1858 scan_tags(sessp	sp, const struct pppoe_hdr* ph)
1859 {
1860 	const char *const end = (const char *)next_tag(ph);
1861 	const char *ptn;
1862 	const struct pppoe_tag *pt = &ph->tag[0];
1863 
1864 	/*
1865 	 * Keep processing tags while a tag header will still fit.
1866 	 */
1867 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1868 
1869 	while((const char*)(pt + 1) <= end) {
1870 		/*
1871 		 * If the tag data would go past the end of the packet, abort.
1872 		 */
1873 		ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
1874 		if(ptn > end)
1875 			return NULL;
1876 
1877 		switch (pt->tag_type) {
1878 		case	PTT_RELAY_SID:
1879 			insert_tag(sp, pt);
1880 			break;
1881 		case	PTT_EOL:
1882 			return NULL;
1883 		case	PTT_SRV_NAME:
1884 		case	PTT_AC_NAME:
1885 		case	PTT_HOST_UNIQ:
1886 		case	PTT_AC_COOKIE:
1887 		case	PTT_VENDOR:
1888 		case	PTT_SRV_ERR:
1889 		case	PTT_SYS_ERR:
1890 		case	PTT_GEN_ERR:
1891 			break;
1892 		}
1893 		pt = (const struct pppoe_tag*)ptn;
1894 	}
1895 	return NULL;
1896 }
1897 
1898 static	int
1899 pppoe_send_event(sessp sp, enum cmd cmdid)
1900 {
1901 	int error;
1902 	struct ng_mesg *msg;
1903 	struct ngpppoe_sts *sts;
1904 
1905 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1906 
1907 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, cmdid,
1908 			sizeof(struct ngpppoe_sts), M_NOWAIT);
1909 	if (msg == NULL)
1910 		return (ENOMEM);
1911 	sts = (struct ngpppoe_sts *)msg->data;
1912 	strncpy(sts->hook, NG_HOOK_NAME(sp->hook), NG_HOOKSIZ);
1913 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1914 	return (error);
1915 }
1916