xref: /freebsd/sys/netgraph/ng_pppoe.c (revision 63d1fd5970ec814904aa0f4580b10a0d302d08b2)
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 static 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 	{
172 	  NGM_PPPOE_COOKIE,
173 	  NGM_PPPOE_SETMAXP,
174 	  "setmaxp",
175 	  &ng_parse_uint16_type,
176 	  NULL
177 	},
178 	{ 0 }
179 };
180 
181 /* Netgraph node type descriptor */
182 static struct ng_type typestruct = {
183 	.version =	NG_ABI_VERSION,
184 	.name =		NG_PPPOE_NODE_TYPE,
185 	.constructor =	ng_pppoe_constructor,
186 	.rcvmsg =	ng_pppoe_rcvmsg,
187 	.shutdown =	ng_pppoe_shutdown,
188 	.newhook =	ng_pppoe_newhook,
189 	.connect =	ng_pppoe_connect,
190 	.rcvdata =	ng_pppoe_rcvdata,
191 	.disconnect =	ng_pppoe_disconnect,
192 	.cmdlist =	ng_pppoe_cmds,
193 };
194 NETGRAPH_INIT(pppoe, &typestruct);
195 
196 /*
197  * States for the session state machine.
198  * These have no meaning if there is no hook attached yet.
199  */
200 enum state {
201     PPPOE_SNONE=0,	/* [both] Initial state */
202     PPPOE_LISTENING,	/* [Daemon] Listening for discover initiation pkt */
203     PPPOE_SINIT,	/* [Client] Sent discovery initiation */
204     PPPOE_PRIMED,	/* [Server] Awaiting PADI from daemon */
205     PPPOE_SOFFER,	/* [Server] Sent offer message  (got PADI)*/
206     PPPOE_SREQ,		/* [Client] Sent a Request */
207     PPPOE_NEWCONNECTED,	/* [Server] Connection established, No data received */
208     PPPOE_CONNECTED,	/* [Both] Connection established, Data received */
209     PPPOE_DEAD		/* [Both] */
210 };
211 
212 #define NUMTAGS 20 /* number of tags we are set up to work with */
213 
214 /*
215  * Information we store for each hook on each node for negotiating the
216  * session. The mbuf and cluster are freed once negotiation has completed.
217  * The whole negotiation block is then discarded.
218  */
219 
220 struct sess_neg {
221 	struct mbuf 		*m; /* holds cluster with last sent packet */
222 	union	packet		*pkt; /* points within the above cluster */
223 	struct callout		handle;   /* see timeout(9) */
224 	u_int			timeout; /* 0,1,2,4,8,16 etc. seconds */
225 	u_int			numtags;
226 	const struct pppoe_tag	*tags[NUMTAGS];
227 	u_int			service_len;
228 	u_int			ac_name_len;
229 
230 	struct datatag		service;
231 	struct datatag		ac_name;
232 };
233 typedef struct sess_neg *negp;
234 
235 /*
236  * Session information that is needed after connection.
237  */
238 struct sess_con {
239 	hook_p  		hook;
240 	uint16_t		Session_ID;
241 	enum state		state;
242 	ng_ID_t			creator;	/* who to notify */
243 	struct pppoe_full_hdr	pkt_hdr;	/* used when connected */
244 	negp			neg;		/* used when negotiating */
245 	LIST_ENTRY(sess_con)	sessions;
246 };
247 typedef struct sess_con *sessp;
248 
249 #define SESSHASHSIZE	0x0100
250 #define SESSHASH(x)	(((x) ^ ((x) >> 8)) & (SESSHASHSIZE - 1))
251 
252 struct sess_hash_entry {
253 	struct mtx	mtx;
254 	LIST_HEAD(hhead, sess_con) head;
255 };
256 
257 /*
258  * Information we store for each node
259  */
260 struct PPPoE {
261 	node_p		node;		/* back pointer to node */
262 	hook_p  	ethernet_hook;
263 	hook_p  	debug_hook;
264 	u_int   	packets_in;	/* packets in from ethernet */
265 	u_int   	packets_out;	/* packets out towards ethernet */
266 	uint32_t	flags;
267 #define	COMPAT_3COM	0x00000001
268 #define	COMPAT_DLINK	0x00000002
269 	struct ether_header	eh;
270 	LIST_HEAD(, sess_con) listeners;
271 	struct sess_hash_entry	sesshash[SESSHASHSIZE];
272 	struct maxptag	max_payload;	/* PPP-Max-Payload (RFC4638) */
273 };
274 typedef struct PPPoE *priv_p;
275 
276 union uniq {
277 	char bytes[sizeof(void *)];
278 	void *pointer;
279 };
280 
281 #define	LEAVE(x) do { error = x; goto quit; } while(0)
282 static void	pppoe_start(sessp sp);
283 static void	pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2);
284 static const	struct pppoe_tag *scan_tags(sessp sp,
285 			const struct pppoe_hdr* ph);
286 static	int	pppoe_send_event(sessp sp, enum cmd cmdid);
287 
288 /*************************************************************************
289  * Some basic utilities  from the Linux version with author's permission.*
290  * Author:	Michal Ostrowski <mostrows@styx.uwaterloo.ca>		 *
291  ************************************************************************/
292 
293 
294 
295 /*
296  * Return the location where the next tag can be put
297  */
298 static __inline const struct pppoe_tag*
299 next_tag(const struct pppoe_hdr* ph)
300 {
301 	return (const struct pppoe_tag*)(((const char*)(ph + 1))
302 	    + ntohs(ph->length));
303 }
304 
305 /*
306  * Look for a tag of a specific type.
307  * Don't trust any length the other end says,
308  * but assume we already sanity checked ph->length.
309  */
310 static const struct pppoe_tag*
311 get_tag(const struct pppoe_hdr* ph, uint16_t idx)
312 {
313 	const char *const end = (const char *)next_tag(ph);
314 	const struct pppoe_tag *pt = (const void *)(ph + 1);
315 	const char *ptn;
316 
317 	/*
318 	 * Keep processing tags while a tag header will still fit.
319 	 */
320 	while((const char*)(pt + 1) <= end) {
321 		/*
322 		 * If the tag data would go past the end of the packet, abort.
323 		 */
324 		ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
325 		if (ptn > end) {
326 			CTR2(KTR_NET, "%20s: invalid length for tag %d",
327 			    __func__, idx);
328 			return (NULL);
329 		}
330 		if (pt->tag_type == idx) {
331 			CTR2(KTR_NET, "%20s: found tag %d", __func__, idx);
332 			return (pt);
333 		}
334 
335 		pt = (const struct pppoe_tag*)ptn;
336 	}
337 
338 	CTR2(KTR_NET, "%20s: not found tag %d", __func__, idx);
339 	return (NULL);
340 }
341 
342 /**************************************************************************
343  * Inlines to initialise or add tags to a session's tag list.
344  **************************************************************************/
345 /*
346  * Initialise the session's tag list.
347  */
348 static void
349 init_tags(sessp sp)
350 {
351 	KASSERT(sp->neg != NULL, ("%s: no neg", __func__));
352 	sp->neg->numtags = 0;
353 }
354 
355 static void
356 insert_tag(sessp sp, const struct pppoe_tag *tp)
357 {
358 	negp neg = sp->neg;
359 	int i;
360 
361 	KASSERT(neg != NULL, ("%s: no neg", __func__));
362 	if ((i = neg->numtags++) < NUMTAGS) {
363 		neg->tags[i] = tp;
364 	} else {
365 		log(LOG_NOTICE, "ng_pppoe: asked to add too many tags to "
366 		    "packet\n");
367 		neg->numtags--;
368 	}
369 }
370 
371 /*
372  * Make up a packet, using the tags filled out for the session.
373  *
374  * Assume that the actual pppoe header and ethernet header
375  * are filled out externally to this routine.
376  * Also assume that neg->wh points to the correct
377  * location at the front of the buffer space.
378  */
379 static void
380 make_packet(sessp sp) {
381 	struct pppoe_full_hdr *wh = &sp->neg->pkt->pkt_header;
382 	const struct pppoe_tag **tag;
383 	char *dp;
384 	int count;
385 	int tlen;
386 	uint16_t length = 0;
387 
388 	KASSERT((sp->neg != NULL) && (sp->neg->m != NULL),
389 	    ("%s: called from wrong state", __func__));
390 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
391 
392 	dp = (char *)(&wh->ph + 1);
393 	for (count = 0, tag = sp->neg->tags;
394 	    ((count < sp->neg->numtags) && (count < NUMTAGS));
395 	    tag++, count++) {
396 		tlen = ntohs((*tag)->tag_len) + sizeof(**tag);
397 		if ((length + tlen) > (ETHER_MAX_LEN - 4 - sizeof(*wh))) {
398 			log(LOG_NOTICE, "ng_pppoe: tags too long\n");
399 			sp->neg->numtags = count;
400 			break;	/* XXX chop off what's too long */
401 		}
402 		bcopy(*tag, (char *)dp, tlen);
403 		length += tlen;
404 		dp += tlen;
405 	}
406  	wh->ph.length = htons(length);
407 	sp->neg->m->m_len = length + sizeof(*wh);
408 	sp->neg->m->m_pkthdr.len = length + sizeof(*wh);
409 }
410 
411 /**************************************************************************
412  * Routines to match a service.						  *
413  **************************************************************************/
414 
415 /*
416  * Find a hook that has a service string that matches that
417  * we are seeking. For now use a simple string.
418  * In the future we may need something like regexp().
419  *
420  * Null string is a wildcard (ANY service), according to RFC2516.
421  * And historical FreeBSD wildcard is also "*".
422  */
423 
424 static hook_p
425 pppoe_match_svc(node_p node, const struct pppoe_tag *tag)
426 {
427 	const priv_p privp = NG_NODE_PRIVATE(node);
428 	sessp sp;
429 
430 	LIST_FOREACH(sp, &privp->listeners, sessions) {
431 		negp neg = sp->neg;
432 
433 		/* Empty Service-Name matches any service. */
434 		if (neg->service_len == 0)
435 			break;
436 
437 		/* Special case for a blank or "*" service name (wildcard). */
438 		if (neg->service_len == 1 && neg->service.data[0] == '*')
439 			break;
440 
441 		/* If the lengths don't match, that aint it. */
442 		if (neg->service_len != ntohs(tag->tag_len))
443 			continue;
444 
445 		if (strncmp((const char *)(tag + 1), neg->service.data,
446 		    ntohs(tag->tag_len)) == 0)
447 			break;
448 	}
449 	CTR3(KTR_NET, "%20s: matched %p for %s", __func__,
450 	    sp?sp->hook:NULL, (const char *)(tag + 1));
451 
452 	return (sp?sp->hook:NULL);
453 }
454 
455 /*
456  * Broadcast the PADI packet in m0 to all listening hooks.
457  * This routine is called when a PADI with empty Service-Name
458  * tag is received. Client should receive PADOs with all
459  * available services.
460  */
461 static int
462 pppoe_broadcast_padi(node_p node, struct mbuf *m0)
463 {
464 	const priv_p privp = NG_NODE_PRIVATE(node);
465 	sessp sp;
466 	int error = 0;
467 
468 	LIST_FOREACH(sp, &privp->listeners, sessions) {
469 		struct mbuf *m;
470 
471 		m = m_dup(m0, M_NOWAIT);
472 		if (m == NULL)
473 			return (ENOMEM);
474 		NG_SEND_DATA_ONLY(error, sp->hook, m);
475 		if (error)
476 			return (error);
477 	}
478 
479 	return (0);
480 }
481 
482 /*
483  * Find a hook, which name equals to given service.
484  */
485 static hook_p
486 pppoe_find_svc(node_p node, const char *svc_name, int svc_len)
487 {
488 	const priv_p privp = NG_NODE_PRIVATE(node);
489 	sessp sp;
490 
491 	LIST_FOREACH(sp, &privp->listeners, sessions) {
492 		negp neg = sp->neg;
493 
494 		if (neg->service_len == svc_len &&
495 		    strncmp(svc_name, neg->service.data, svc_len) == 0)
496 			return (sp->hook);
497 	}
498 
499 	return (NULL);
500 }
501 
502 /**************************************************************************
503  * Routines to find a particular session that matches an incoming packet. *
504  **************************************************************************/
505 /* Find free session and add to hash. */
506 static uint16_t
507 pppoe_getnewsession(sessp sp)
508 {
509 	const priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
510 	static uint16_t pppoe_sid = 1;
511 	sessp	tsp;
512 	uint16_t val, hash;
513 
514 restart:
515 	/* Atomicity is not needed here as value will be checked. */
516 	val = pppoe_sid++;
517 	/* Spec says 0xFFFF is reserved, also don't use 0x0000. */
518 	if (val == 0xffff || val == 0x0000)
519 		val = pppoe_sid = 1;
520 
521 	/* Check it isn't already in use. */
522 	hash = SESSHASH(val);
523 	mtx_lock(&privp->sesshash[hash].mtx);
524 	LIST_FOREACH(tsp, &privp->sesshash[hash].head, sessions) {
525 		if (tsp->Session_ID == val)
526 			break;
527 	}
528 	if (!tsp) {
529 		sp->Session_ID = val;
530 		LIST_INSERT_HEAD(&privp->sesshash[hash].head, sp, sessions);
531 	}
532 	mtx_unlock(&privp->sesshash[hash].mtx);
533 	if (tsp)
534 		goto restart;
535 
536 	CTR2(KTR_NET, "%20s: new sid %d", __func__, val);
537 
538 	return (val);
539 }
540 
541 /* Add specified session to hash. */
542 static void
543 pppoe_addsession(sessp sp)
544 {
545 	const priv_p	privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
546 	uint16_t	hash = SESSHASH(sp->Session_ID);
547 
548 	mtx_lock(&privp->sesshash[hash].mtx);
549 	LIST_INSERT_HEAD(&privp->sesshash[hash].head, sp, sessions);
550 	mtx_unlock(&privp->sesshash[hash].mtx);
551 }
552 
553 /* Delete specified session from hash. */
554 static void
555 pppoe_delsession(sessp sp)
556 {
557 	const priv_p	privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
558 	uint16_t	hash = SESSHASH(sp->Session_ID);
559 
560 	mtx_lock(&privp->sesshash[hash].mtx);
561 	LIST_REMOVE(sp, sessions);
562 	mtx_unlock(&privp->sesshash[hash].mtx);
563 }
564 
565 /* Find matching peer/session combination. */
566 static sessp
567 pppoe_findsession(priv_p privp, const struct pppoe_full_hdr *wh)
568 {
569 	uint16_t 	session = ntohs(wh->ph.sid);
570 	uint16_t	hash = SESSHASH(session);
571 	sessp		sp = NULL;
572 
573 	mtx_lock(&privp->sesshash[hash].mtx);
574 	LIST_FOREACH(sp, &privp->sesshash[hash].head, sessions) {
575 		if (sp->Session_ID == session &&
576 		    bcmp(sp->pkt_hdr.eh.ether_dhost,
577 		     wh->eh.ether_shost, ETHER_ADDR_LEN) == 0) {
578 			break;
579 		}
580 	}
581 	mtx_unlock(&privp->sesshash[hash].mtx);
582 	CTR3(KTR_NET, "%20s: matched %p for %d", __func__, sp?sp->hook:NULL,
583 	    session);
584 
585 	return (sp);
586 }
587 
588 static hook_p
589 pppoe_finduniq(node_p node, const struct pppoe_tag *tag)
590 {
591 	hook_p	hook = NULL;
592 	union uniq uniq;
593 
594 	bcopy(tag + 1, uniq.bytes, sizeof(void *));
595 	/* Cycle through all known hooks. */
596 	LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
597 		/* Skip any nonsession hook. */
598 		if (NG_HOOK_PRIVATE(hook) == NULL)
599 			continue;
600 		if (uniq.pointer == NG_HOOK_PRIVATE(hook))
601 			break;
602 	}
603 	CTR3(KTR_NET, "%20s: matched %p for %p", __func__, hook, uniq.pointer);
604 
605 	return (hook);
606 }
607 
608 /**************************************************************************
609  * Start of Netgraph entrypoints.					  *
610  **************************************************************************/
611 
612 /*
613  * Allocate the private data structure and link it with node.
614  */
615 static int
616 ng_pppoe_constructor(node_p node)
617 {
618 	priv_p	privp;
619 	int	i;
620 
621 	/* Initialize private descriptor. */
622 	privp = malloc(sizeof(*privp), M_NETGRAPH_PPPOE, M_WAITOK | M_ZERO);
623 
624 	/* Link structs together; this counts as our one reference to *node. */
625 	NG_NODE_SET_PRIVATE(node, privp);
626 	privp->node = node;
627 
628 	/* Initialize to standard mode. */
629 	memset(&privp->eh.ether_dhost, 0xff, ETHER_ADDR_LEN);
630 	privp->eh.ether_type = ETHERTYPE_PPPOE_DISC;
631 
632 	LIST_INIT(&privp->listeners);
633 	for (i = 0; i < SESSHASHSIZE; i++) {
634 	    mtx_init(&privp->sesshash[i].mtx, "PPPoE hash mutex", NULL, MTX_DEF);
635 	    LIST_INIT(&privp->sesshash[i].head);
636 	}
637 
638 	CTR3(KTR_NET, "%20s: created node [%x] (%p)",
639 	    __func__, node->nd_ID, node);
640 
641 	return (0);
642 }
643 
644 /*
645  * Give our ok for a hook to be added...
646  * point the hook's private info to the hook structure.
647  *
648  * The following hook names are special:
649  *  "ethernet":  the hook that should be connected to a NIC.
650  *  "debug":	copies of data sent out here  (when I write the code).
651  * All other hook names need only be unique. (the framework checks this).
652  */
653 static int
654 ng_pppoe_newhook(node_p node, hook_p hook, const char *name)
655 {
656 	const priv_p privp = NG_NODE_PRIVATE(node);
657 	sessp sp;
658 
659 	if (strcmp(name, NG_PPPOE_HOOK_ETHERNET) == 0) {
660 		privp->ethernet_hook = hook;
661 		NG_HOOK_SET_RCVDATA(hook, ng_pppoe_rcvdata_ether);
662 	} else if (strcmp(name, NG_PPPOE_HOOK_DEBUG) == 0) {
663 		privp->debug_hook = hook;
664 		NG_HOOK_SET_RCVDATA(hook, ng_pppoe_rcvdata_debug);
665 	} else {
666 		/*
667 		 * Any other unique name is OK.
668 		 * The infrastructure has already checked that it's unique,
669 		 * so just allocate it and hook it in.
670 		 */
671 		sp = malloc(sizeof(*sp), M_NETGRAPH_PPPOE, M_NOWAIT | M_ZERO);
672 		if (sp == NULL)
673 			return (ENOMEM);
674 
675 		NG_HOOK_SET_PRIVATE(hook, sp);
676 		sp->hook = hook;
677 	}
678 	CTR5(KTR_NET, "%20s: node [%x] (%p) connected hook %s (%p)",
679 	    __func__, node->nd_ID, node, name, hook);
680 
681 	return(0);
682 }
683 
684 /*
685  * Hook has been added successfully. Request the MAC address of
686  * the underlying Ethernet node.
687  */
688 static int
689 ng_pppoe_connect(hook_p hook)
690 {
691 	const priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
692 	struct ng_mesg *msg;
693 	int error;
694 
695 	if (hook != privp->ethernet_hook)
696 		return (0);
697 
698 	/*
699 	 * If this is Ethernet hook, then request MAC address
700 	 * from our downstream.
701 	 */
702 	NG_MKMESSAGE(msg, NGM_ETHER_COOKIE, NGM_ETHER_GET_ENADDR, 0, M_NOWAIT);
703 	if (msg == NULL)
704 		return (ENOBUFS);
705 
706 	/*
707 	 * Our hook and peer hook have HK_INVALID flag set,
708 	 * so we can't use NG_SEND_MSG_HOOK() macro here.
709 	 */
710 	NG_SEND_MSG_ID(error, privp->node, msg,
711 	    NG_NODE_ID(NG_PEER_NODE(privp->ethernet_hook)),
712 	    NG_NODE_ID(privp->node));
713 
714 	return (error);
715 }
716 /*
717  * Get a netgraph control message.
718  * Check it is one we understand. If needed, send a response.
719  * We sometimes save the address for an async action later.
720  * Always free the message.
721  */
722 static int
723 ng_pppoe_rcvmsg(node_p node, item_p item, hook_p lasthook)
724 {
725 	priv_p privp = NG_NODE_PRIVATE(node);
726 	struct ngpppoe_init_data *ourmsg = NULL;
727 	struct ng_mesg *resp = NULL;
728 	int error = 0;
729 	hook_p hook = NULL;
730 	sessp sp = NULL;
731 	negp neg = NULL;
732 	struct ng_mesg *msg;
733 
734 	NGI_GET_MSG(item, msg);
735 	CTR5(KTR_NET, "%20s: node [%x] (%p) got message %d with cookie %d",
736 	    __func__, node->nd_ID, node, msg->header.cmd,
737 	    msg->header.typecookie);
738 
739 	/* Deal with message according to cookie and command. */
740 	switch (msg->header.typecookie) {
741 	case NGM_PPPOE_COOKIE:
742 		switch (msg->header.cmd) {
743 		case NGM_PPPOE_CONNECT:
744 		case NGM_PPPOE_LISTEN:
745 		case NGM_PPPOE_OFFER:
746 		case NGM_PPPOE_SERVICE:
747 			ourmsg = (struct ngpppoe_init_data *)msg->data;
748 			if (msg->header.arglen < sizeof(*ourmsg)) {
749 				log(LOG_ERR, "ng_pppoe[%x]: init data too "
750 				    "small\n", node->nd_ID);
751 				LEAVE(EMSGSIZE);
752 			}
753 			if (msg->header.arglen - sizeof(*ourmsg) >
754 			    PPPOE_SERVICE_NAME_SIZE) {
755 				log(LOG_ERR, "ng_pppoe[%x]: service name "
756 				    "too big\n", node->nd_ID);
757 				LEAVE(EMSGSIZE);
758 			}
759 			if (msg->header.arglen - sizeof(*ourmsg) <
760 			    ourmsg->data_len) {
761 				log(LOG_ERR, "ng_pppoe[%x]: init data has bad "
762 				    "length, %d should be %zd\n", node->nd_ID,
763 				    ourmsg->data_len,
764 				    msg->header.arglen - sizeof (*ourmsg));
765 				LEAVE(EMSGSIZE);
766 			}
767 
768 			/* Make sure strcmp will terminate safely. */
769 			ourmsg->hook[sizeof(ourmsg->hook) - 1] = '\0';
770 
771 			/* Find hook by name. */
772 			hook = ng_findhook(node, ourmsg->hook);
773 			if (hook == NULL)
774 				LEAVE(ENOENT);
775 
776 			sp = NG_HOOK_PRIVATE(hook);
777 			if (sp == NULL)
778 				LEAVE(EINVAL);
779 
780 			if (msg->header.cmd == NGM_PPPOE_LISTEN) {
781 				/*
782 				 * Ensure we aren't already listening for this
783 				 * service.
784 				 */
785 				if (pppoe_find_svc(node, ourmsg->data,
786 				    ourmsg->data_len) != NULL)
787 					LEAVE(EEXIST);
788 			}
789 
790 			/*
791 			 * PPPOE_SERVICE advertisements are set up
792 			 * on sessions that are in PRIMED state.
793 			 */
794 			if (msg->header.cmd == NGM_PPPOE_SERVICE)
795 				break;
796 
797 			if (sp->state != PPPOE_SNONE) {
798 				log(LOG_NOTICE, "ng_pppoe[%x]: Session already "
799 				    "active\n", node->nd_ID);
800 				LEAVE(EISCONN);
801 			}
802 
803 			/*
804 			 * Set up prototype header.
805 			 */
806 			neg = malloc(sizeof(*neg), M_NETGRAPH_PPPOE,
807 			    M_NOWAIT | M_ZERO);
808 
809 			if (neg == NULL)
810 				LEAVE(ENOMEM);
811 
812 			neg->m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
813 			if (neg->m == NULL) {
814 				free(neg, M_NETGRAPH_PPPOE);
815 				LEAVE(ENOBUFS);
816 			}
817 			neg->m->m_pkthdr.rcvif = NULL;
818 			sp->neg = neg;
819 			ng_callout_init(&neg->handle);
820 			neg->m->m_len = sizeof(struct pppoe_full_hdr);
821 			neg->pkt = mtod(neg->m, union packet*);
822 			memcpy((void *)&neg->pkt->pkt_header.eh,
823 			    &privp->eh, sizeof(struct ether_header));
824 			neg->pkt->pkt_header.ph.ver = 0x1;
825 			neg->pkt->pkt_header.ph.type = 0x1;
826 			neg->pkt->pkt_header.ph.sid = 0x0000;
827 			neg->timeout = 0;
828 
829 			sp->creator = NGI_RETADDR(item);
830 		}
831 		switch (msg->header.cmd) {
832 		case NGM_PPPOE_GET_STATUS:
833 		    {
834 			struct ngpppoestat *stats;
835 
836 			NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT);
837 			if (!resp)
838 				LEAVE(ENOMEM);
839 
840 			stats = (struct ngpppoestat *) resp->data;
841 			stats->packets_in = privp->packets_in;
842 			stats->packets_out = privp->packets_out;
843 			break;
844 		    }
845 		case NGM_PPPOE_CONNECT:
846 		    {
847 			/*
848 			 * Check the hook exists and is Uninitialised.
849 			 * Send a PADI request, and start the timeout logic.
850 			 * Store the originator of this message so we can send
851 			 * a success of fail message to them later.
852 			 * Move the session to SINIT.
853 			 * Set up the session to the correct state and
854 			 * start it.
855 			 */
856 			int	i, acnlen = 0, acnsep = 0, srvlen;
857 			for (i = 0; i < ourmsg->data_len; i++) {
858 				if (ourmsg->data[i] == '\\') {
859 					acnlen = i;
860 					acnsep = 1;
861 					break;
862 				}
863 			}
864 			srvlen = ourmsg->data_len - acnlen - acnsep;
865 
866 			bcopy(ourmsg->data, neg->ac_name.data, acnlen);
867 			neg->ac_name_len = acnlen;
868 
869 			neg->service.hdr.tag_type = PTT_SRV_NAME;
870 			neg->service.hdr.tag_len = htons((uint16_t)srvlen);
871 			bcopy(ourmsg->data + acnlen + acnsep,
872 			    neg->service.data, srvlen);
873 			neg->service_len = srvlen;
874 			pppoe_start(sp);
875 			break;
876 		    }
877 		case NGM_PPPOE_LISTEN:
878 			/*
879 			 * Check the hook exists and is Uninitialised.
880 			 * Install the service matching string.
881 			 * Store the originator of this message so we can send
882 			 * a success of fail message to them later.
883 			 * Move the hook to 'LISTENING'
884 			 */
885 			neg->service.hdr.tag_type = PTT_SRV_NAME;
886 			neg->service.hdr.tag_len =
887 			    htons((uint16_t)ourmsg->data_len);
888 
889 			if (ourmsg->data_len)
890 				bcopy(ourmsg->data, neg->service.data,
891 				    ourmsg->data_len);
892 			neg->service_len = ourmsg->data_len;
893 			neg->pkt->pkt_header.ph.code = PADT_CODE;
894 			/*
895 			 * Wait for PADI packet coming from Ethernet.
896 			 */
897 			sp->state = PPPOE_LISTENING;
898 			LIST_INSERT_HEAD(&privp->listeners, sp, sessions);
899 			break;
900 		case NGM_PPPOE_OFFER:
901 			/*
902 			 * Check the hook exists and is Uninitialised.
903 			 * Store the originator of this message so we can send
904 			 * a success of fail message to them later.
905 			 * Store the AC-Name given and go to PRIMED.
906 			 */
907 			neg->ac_name.hdr.tag_type = PTT_AC_NAME;
908 			neg->ac_name.hdr.tag_len =
909 			    htons((uint16_t)ourmsg->data_len);
910 			if (ourmsg->data_len)
911 				bcopy(ourmsg->data, neg->ac_name.data,
912 				    ourmsg->data_len);
913 			neg->ac_name_len = ourmsg->data_len;
914 			neg->pkt->pkt_header.ph.code = PADO_CODE;
915 			/*
916 			 * Wait for PADI packet coming from hook.
917 			 */
918 			sp->state = PPPOE_PRIMED;
919 			break;
920 		case NGM_PPPOE_SERVICE:
921 			/*
922 			 * Check the session is primed.
923 			 * for now just allow ONE service to be advertised.
924 			 * If you do it twice you just overwrite.
925 			 */
926 			if (sp->state != PPPOE_PRIMED) {
927 				log(LOG_NOTICE, "ng_pppoe[%x]: session not "
928 				    "primed\n", node->nd_ID);
929 				LEAVE(EISCONN);
930 			}
931 			neg = sp->neg;
932 			neg->service.hdr.tag_type = PTT_SRV_NAME;
933 			neg->service.hdr.tag_len =
934 			    htons((uint16_t)ourmsg->data_len);
935 
936 			if (ourmsg->data_len)
937 				bcopy(ourmsg->data, neg->service.data,
938 				    ourmsg->data_len);
939 			neg->service_len = ourmsg->data_len;
940 			break;
941 		case NGM_PPPOE_SETMODE:
942 		    {
943 			char *s;
944 			size_t len;
945 
946 			if (msg->header.arglen == 0)
947 				LEAVE(EINVAL);
948 
949 			s = (char *)msg->data;
950 			len = msg->header.arglen - 1;
951 
952 			/* Search for matching mode string. */
953 			if (len == strlen(NG_PPPOE_STANDARD) &&
954 			    (strncmp(NG_PPPOE_STANDARD, s, len) == 0)) {
955 				privp->flags = 0;
956 				privp->eh.ether_type = ETHERTYPE_PPPOE_DISC;
957 				break;
958 			}
959 			if (len == strlen(NG_PPPOE_3COM) &&
960 			    (strncmp(NG_PPPOE_3COM, s, len) == 0)) {
961 				privp->flags |= COMPAT_3COM;
962 				privp->eh.ether_type =
963 				    ETHERTYPE_PPPOE_3COM_DISC;
964 				break;
965 			}
966 			if (len == strlen(NG_PPPOE_DLINK) &&
967 			    (strncmp(NG_PPPOE_DLINK, s, len) == 0)) {
968 				privp->flags |= COMPAT_DLINK;
969 				break;
970 			}
971 			error = EINVAL;
972 			break;
973 		    }
974 		case NGM_PPPOE_GETMODE:
975 		    {
976 			char *s;
977 			size_t len = 0;
978 
979 			if (privp->flags == 0)
980 				len += strlen(NG_PPPOE_STANDARD) + 1;
981 			if (privp->flags & COMPAT_3COM)
982 				len += strlen(NG_PPPOE_3COM) + 1;
983 			if (privp->flags & COMPAT_DLINK)
984 				len += strlen(NG_PPPOE_DLINK) + 1;
985 
986 			NG_MKRESPONSE(resp, msg, len, M_NOWAIT);
987 			if (resp == NULL)
988 				LEAVE(ENOMEM);
989 
990 			s = (char *)resp->data;
991 			if (privp->flags == 0) {
992 				len = strlen(NG_PPPOE_STANDARD);
993 				strlcpy(s, NG_PPPOE_STANDARD, len + 1);
994 				break;
995 			}
996 			if (privp->flags & COMPAT_3COM) {
997 				len = strlen(NG_PPPOE_3COM);
998 				strlcpy(s, NG_PPPOE_3COM, len + 1);
999 				s += len;
1000 			}
1001 			if (privp->flags & COMPAT_DLINK) {
1002 				if (s != resp->data)
1003 					*s++ = '|';
1004 				len = strlen(NG_PPPOE_DLINK);
1005 				strlcpy(s, NG_PPPOE_DLINK, len + 1);
1006 			}
1007 			break;
1008 		    }
1009 		case NGM_PPPOE_SETENADDR:
1010 			if (msg->header.arglen != ETHER_ADDR_LEN)
1011 				LEAVE(EINVAL);
1012 			bcopy(msg->data, &privp->eh.ether_shost,
1013 			    ETHER_ADDR_LEN);
1014 			break;
1015 		case NGM_PPPOE_SETMAXP:
1016 			if (msg->header.arglen != sizeof(uint16_t))
1017 				LEAVE(EINVAL);
1018 			privp->max_payload.hdr.tag_type = PTT_MAX_PAYL;
1019 			privp->max_payload.hdr.tag_len = htons(sizeof(uint16_t));
1020 			privp->max_payload.data = htons(*((uint16_t *)msg->data));
1021 			break;
1022 		default:
1023 			LEAVE(EINVAL);
1024 		}
1025 		break;
1026 	case NGM_ETHER_COOKIE:
1027 		if (!(msg->header.flags & NGF_RESP))
1028 			LEAVE(EINVAL);
1029 		switch (msg->header.cmd) {
1030 		case NGM_ETHER_GET_ENADDR:
1031 			if (msg->header.arglen != ETHER_ADDR_LEN)
1032 				LEAVE(EINVAL);
1033 			bcopy(msg->data, &privp->eh.ether_shost,
1034 			    ETHER_ADDR_LEN);
1035 			break;
1036 		default:
1037 			LEAVE(EINVAL);
1038 		}
1039 		break;
1040 	default:
1041 		LEAVE(EINVAL);
1042 	}
1043 
1044 	/* Take care of synchronous response, if any. */
1045 quit:
1046 	CTR2(KTR_NET, "%20s: returning %d", __func__, error);
1047 	NG_RESPOND_MSG(error, node, item, resp);
1048 	/* Free the message and return. */
1049 	NG_FREE_MSG(msg);
1050 	return(error);
1051 }
1052 
1053 /*
1054  * Start a client into the first state. A separate function because
1055  * it can be needed if the negotiation times out.
1056  */
1057 static void
1058 pppoe_start(sessp sp)
1059 {
1060 	hook_p	hook = sp->hook;
1061 	node_p	node = NG_HOOK_NODE(hook);
1062 	priv_p	privp = NG_NODE_PRIVATE(node);
1063 	negp	neg = sp->neg;
1064 	struct {
1065 		struct pppoe_tag hdr;
1066 		union	uniq	data;
1067 	} __packed uniqtag;
1068 	struct  mbuf *m0;
1069 	int	error;
1070 
1071 	/*
1072 	 * Kick the state machine into starting up.
1073 	 */
1074 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1075 	sp->state = PPPOE_SINIT;
1076 	/*
1077 	 * Reset the packet header to broadcast. Since we are
1078 	 * in a client mode use configured ethertype.
1079 	 */
1080 	memcpy((void *)&neg->pkt->pkt_header.eh, &privp->eh,
1081 	    sizeof(struct ether_header));
1082 	neg->pkt->pkt_header.ph.code = PADI_CODE;
1083 	uniqtag.hdr.tag_type = PTT_HOST_UNIQ;
1084 	uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(uniqtag.data));
1085 	uniqtag.data.pointer = sp;
1086 	init_tags(sp);
1087 	insert_tag(sp, &uniqtag.hdr);
1088 	insert_tag(sp, &neg->service.hdr);
1089 	if (privp->max_payload.data != 0)
1090 		insert_tag(sp, &privp->max_payload.hdr);
1091 	make_packet(sp);
1092 	/*
1093 	 * Send packet and prepare to retransmit it after timeout.
1094 	 */
1095 	ng_callout(&neg->handle, node, hook, PPPOE_INITIAL_TIMEOUT * hz,
1096 	    pppoe_ticker, NULL, 0);
1097 	neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1098 	m0 = m_copypacket(neg->m, M_NOWAIT);
1099 	NG_SEND_DATA_ONLY(error, privp->ethernet_hook, m0);
1100 }
1101 
1102 static int
1103 send_acname(sessp sp, const struct pppoe_tag *tag)
1104 {
1105 	int error, tlen;
1106 	struct ng_mesg *msg;
1107 	struct ngpppoe_sts *sts;
1108 
1109 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1110 
1111 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_ACNAME,
1112 	    sizeof(struct ngpppoe_sts), M_NOWAIT);
1113 	if (msg == NULL)
1114 		return (ENOMEM);
1115 
1116 	sts = (struct ngpppoe_sts *)msg->data;
1117 	tlen = min(NG_HOOKSIZ - 1, ntohs(tag->tag_len));
1118 	strncpy(sts->hook, (const char *)(tag + 1), tlen);
1119 	sts->hook[tlen] = '\0';
1120 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1121 
1122 	return (error);
1123 }
1124 
1125 static int
1126 send_sessionid(sessp sp)
1127 {
1128 	int error;
1129 	struct ng_mesg *msg;
1130 
1131 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1132 
1133 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SESSIONID,
1134 	    sizeof(uint16_t), M_NOWAIT);
1135 	if (msg == NULL)
1136 		return (ENOMEM);
1137 
1138 	*(uint16_t *)msg->data = sp->Session_ID;
1139 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1140 
1141 	return (error);
1142 }
1143 
1144 static int
1145 send_maxp(sessp sp, const struct pppoe_tag *tag)
1146 {
1147 	int error;
1148 	struct ng_mesg *msg;
1149 	struct ngpppoe_maxp *maxp;
1150 
1151 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1152 
1153 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SETMAXP,
1154 	    sizeof(struct ngpppoe_maxp), M_NOWAIT);
1155 	if (msg == NULL)
1156 		return (ENOMEM);
1157 
1158 	maxp = (struct ngpppoe_maxp *)msg->data;
1159 	strncpy(maxp->hook, NG_HOOK_NAME(sp->hook), NG_HOOKSIZ);
1160 	maxp->data = ntohs(((const struct maxptag *)tag)->data);
1161 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1162 
1163 	return (error);
1164 }
1165 
1166 /*
1167  * Receive data from session hook and do something with it.
1168  */
1169 static int
1170 ng_pppoe_rcvdata(hook_p hook, item_p item)
1171 {
1172 	node_p			node = NG_HOOK_NODE(hook);
1173 	const priv_p		privp = NG_NODE_PRIVATE(node);
1174 	sessp			sp = NG_HOOK_PRIVATE(hook);
1175 	struct pppoe_full_hdr	*wh;
1176 	struct mbuf		*m;
1177 	int			error;
1178 
1179 	CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1180 	    __func__, node->nd_ID, node, item, hook->hk_name, hook);
1181 
1182 	NGI_GET_M(item, m);
1183 	switch (sp->state) {
1184 	case	PPPOE_NEWCONNECTED:
1185 	case	PPPOE_CONNECTED: {
1186 		/*
1187 		 * Remove PPP address and control fields, if any.
1188 		 * For example, ng_ppp(4) always sends LCP packets
1189 		 * with address and control fields as required by
1190 		 * generic PPP. PPPoE is an exception to the rule.
1191 		 */
1192 		if (m->m_pkthdr.len >= 2) {
1193 			if (m->m_len < 2 && !(m = m_pullup(m, 2)))
1194 				LEAVE(ENOBUFS);
1195 			if (mtod(m, u_char *)[0] == 0xff &&
1196 			    mtod(m, u_char *)[1] == 0x03)
1197 				m_adj(m, 2);
1198 		}
1199 		/*
1200 		 * Bang in a pre-made header, and set the length up
1201 		 * to be correct. Then send it to the ethernet driver.
1202 		 */
1203 		M_PREPEND(m, sizeof(*wh), M_NOWAIT);
1204 		if (m == NULL)
1205 			LEAVE(ENOBUFS);
1206 
1207 		wh = mtod(m, struct pppoe_full_hdr *);
1208 		bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1209 		wh->ph.length = htons(m->m_pkthdr.len - sizeof(*wh));
1210 		NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m);
1211 		privp->packets_out++;
1212 		break;
1213 		}
1214 	case	PPPOE_PRIMED: {
1215 		struct {
1216 			struct pppoe_tag hdr;
1217 			union	uniq	data;
1218 		} __packed 	uniqtag;
1219 		const struct pppoe_tag	*tag;
1220 		struct mbuf 	*m0;
1221 		const struct pppoe_hdr	*ph;
1222 		negp		neg = sp->neg;
1223 	        uint16_t	session;
1224 		uint16_t	length;
1225 		uint8_t		code;
1226 
1227 		/*
1228 		 * A PADI packet is being returned by the application
1229 		 * that has set up this hook. This indicates that it
1230 		 * wants us to offer service.
1231 		 */
1232 		if (m->m_len < sizeof(*wh)) {
1233 			m = m_pullup(m, sizeof(*wh));
1234 			if (m == NULL)
1235 				LEAVE(ENOBUFS);
1236 		}
1237 		wh = mtod(m, struct pppoe_full_hdr *);
1238 		ph = &wh->ph;
1239 		session = ntohs(wh->ph.sid);
1240 		length = ntohs(wh->ph.length);
1241 		code = wh->ph.code;
1242 		/* Use peers mode in session. */
1243 		neg->pkt->pkt_header.eh.ether_type = wh->eh.ether_type;
1244 		if (code != PADI_CODE)
1245 			LEAVE(EINVAL);
1246 		ng_uncallout(&neg->handle, node);
1247 
1248 		/*
1249 		 * This is the first time we hear
1250 		 * from the client, so note it's
1251 		 * unicast address, replacing the
1252 		 * broadcast address.
1253 		 */
1254 		bcopy(wh->eh.ether_shost,
1255 			neg->pkt->pkt_header.eh.ether_dhost,
1256 			ETHER_ADDR_LEN);
1257 		sp->state = PPPOE_SOFFER;
1258 		neg->timeout = 0;
1259 		neg->pkt->pkt_header.ph.code = PADO_CODE;
1260 
1261 		/*
1262 		 * Start working out the tags to respond with.
1263 		 */
1264 		uniqtag.hdr.tag_type = PTT_AC_COOKIE;
1265 		uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(sp));
1266 		uniqtag.data.pointer = sp;
1267 		init_tags(sp);
1268 		insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1269 		if ((tag = get_tag(ph, PTT_SRV_NAME)))
1270 			insert_tag(sp, tag);	  /* return service */
1271 		/*
1272 		 * If we have a NULL service request
1273 		 * and have an extra service defined in this hook,
1274 		 * then also add a tag for the extra service.
1275 		 * XXX this is a hack. eventually we should be able
1276 		 * to support advertising many services, not just one
1277 		 */
1278 		if (((tag == NULL) || (tag->tag_len == 0)) &&
1279 		    (neg->service.hdr.tag_len != 0)) {
1280 			insert_tag(sp, &neg->service.hdr); /* SERVICE */
1281 		}
1282 		if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1283 			insert_tag(sp, tag); /* returned hostunique */
1284 		insert_tag(sp, &uniqtag.hdr);
1285 		scan_tags(sp, ph);
1286 		make_packet(sp);
1287 		/*
1288 		 * Send the offer but if they don't respond
1289 		 * in PPPOE_OFFER_TIMEOUT seconds, forget about it.
1290 		 */
1291 		ng_callout(&neg->handle, node, hook, PPPOE_OFFER_TIMEOUT * hz,
1292 		    pppoe_ticker, NULL, 0);
1293 		m0 = m_copypacket(sp->neg->m, M_NOWAIT);
1294 		NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1295 		privp->packets_out++;
1296 		break;
1297 		}
1298 
1299 	/*
1300 	 * Packets coming from the hook make no sense
1301 	 * to sessions in the rest of states. Throw them away.
1302 	 */
1303 	default:
1304 		LEAVE(ENETUNREACH);
1305 	}
1306 quit:
1307 	if (item)
1308 		NG_FREE_ITEM(item);
1309 	NG_FREE_M(m);
1310 	return (error);
1311 }
1312 
1313 /*
1314  * Receive data from ether and do something with it.
1315  */
1316 static int
1317 ng_pppoe_rcvdata_ether(hook_p hook, item_p item)
1318 {
1319 	node_p			node = NG_HOOK_NODE(hook);
1320 	const priv_p		privp = NG_NODE_PRIVATE(node);
1321 	sessp			sp;
1322 	const struct pppoe_tag	*utag = NULL, *tag = NULL;
1323 	const struct pppoe_full_hdr *wh;
1324 	const struct pppoe_hdr	*ph;
1325 	negp			neg = NULL;
1326 	struct mbuf		*m;
1327 	hook_p 			sendhook;
1328 	int			error = 0;
1329 	uint16_t		session;
1330 	uint16_t		length;
1331 	uint8_t			code;
1332 	struct	mbuf 		*m0;
1333 
1334 	CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1335 	    __func__, node->nd_ID, node, item, hook->hk_name, hook);
1336 
1337 	NGI_GET_M(item, m);
1338 	/*
1339 	 * Dig out various fields from the packet.
1340 	 * Use them to decide where to send it.
1341 	 */
1342 	privp->packets_in++;
1343 	if( m->m_len < sizeof(*wh)) {
1344 		m = m_pullup(m, sizeof(*wh)); /* Checks length */
1345 		if (m == NULL) {
1346 			log(LOG_NOTICE, "ng_pppoe[%x]: couldn't "
1347 			    "m_pullup(wh)\n", node->nd_ID);
1348 			LEAVE(ENOBUFS);
1349 		}
1350 	}
1351 	wh = mtod(m, struct pppoe_full_hdr *);
1352 	length = ntohs(wh->ph.length);
1353 	switch(wh->eh.ether_type) {
1354 	case	ETHERTYPE_PPPOE_3COM_DISC: /* fall through */
1355 	case	ETHERTYPE_PPPOE_DISC:
1356 		/*
1357 		 * We need to try to make sure that the tag area
1358 		 * is contiguous, or we could wander off the end
1359 		 * of a buffer and make a mess.
1360 		 * (Linux wouldn't have this problem).
1361 		 */
1362 		if (m->m_pkthdr.len <= MHLEN) {
1363 			if( m->m_len < m->m_pkthdr.len) {
1364 				m = m_pullup(m, m->m_pkthdr.len);
1365 				if (m == NULL) {
1366 					log(LOG_NOTICE, "ng_pppoe[%x]: "
1367 					    "couldn't m_pullup(pkthdr)\n",
1368 					    node->nd_ID);
1369 					LEAVE(ENOBUFS);
1370 				}
1371 			}
1372 		}
1373 		if (m->m_len != m->m_pkthdr.len) {
1374 			/*
1375 			 * It's not all in one piece.
1376 			 * We need to do extra work.
1377 			 * Put it into a cluster.
1378 			 */
1379 			struct mbuf *n;
1380 			n = m_dup(m, M_NOWAIT);
1381 			m_freem(m);
1382 			m = n;
1383 			if (m) {
1384 				/* just check we got a cluster */
1385 				if (m->m_len != m->m_pkthdr.len) {
1386 					m_freem(m);
1387 					m = NULL;
1388 				}
1389 			}
1390 			if (m == NULL) {
1391 				log(LOG_NOTICE, "ng_pppoe[%x]: packet "
1392 				    "fragmented\n", node->nd_ID);
1393 				LEAVE(EMSGSIZE);
1394 			}
1395 		}
1396 		wh = mtod(m, struct pppoe_full_hdr *);
1397 		length = ntohs(wh->ph.length);
1398 		ph = &wh->ph;
1399 		session = ntohs(wh->ph.sid);
1400 		code = wh->ph.code;
1401 
1402 		switch(code) {
1403 		case	PADI_CODE:
1404 			/*
1405 			 * We are a server:
1406 			 * Look for a hook with the required service and send
1407 			 * the ENTIRE packet up there. It should come back to
1408 			 * a new hook in PRIMED state. Look there for further
1409 			 * processing.
1410 			 */
1411 			tag = get_tag(ph, PTT_SRV_NAME);
1412 			if (tag == NULL) {
1413 				CTR1(KTR_NET, "%20s: PADI w/o Service-Name",
1414 				    __func__);
1415 				LEAVE(ENETUNREACH);
1416 			}
1417 
1418 			/*
1419 			 * First, try to match Service-Name against our
1420 			 * listening hooks. If no success and we are in D-Link
1421 			 * compat mode and Service-Name is empty, then we
1422 			 * broadcast the PADI to all listening hooks.
1423 			 */
1424 			sendhook = pppoe_match_svc(node, tag);
1425 			if (sendhook != NULL)
1426 				NG_FWD_NEW_DATA(error, item, sendhook, m);
1427 			else if (privp->flags & COMPAT_DLINK &&
1428 				 ntohs(tag->tag_len) == 0)
1429 				error = pppoe_broadcast_padi(node, m);
1430 			else
1431 				error = ENETUNREACH;
1432 			break;
1433 		case	PADO_CODE:
1434 			/*
1435 			 * We are a client:
1436 			 * Use the host_uniq tag to find the hook this is in
1437 			 * response to. Received #2, now send #3
1438 			 * For now simply accept the first we receive.
1439 			 */
1440 			utag = get_tag(ph, PTT_HOST_UNIQ);
1441 			if ((utag == NULL) ||
1442 			    (ntohs(utag->tag_len) != sizeof(sp))) {
1443 				log(LOG_NOTICE, "ng_pppoe[%x]: no host "
1444 				    "unique field\n", node->nd_ID);
1445 				LEAVE(ENETUNREACH);
1446 			}
1447 
1448 			sendhook = pppoe_finduniq(node, utag);
1449 			if (sendhook == NULL) {
1450 				log(LOG_NOTICE, "ng_pppoe[%x]: no "
1451 				    "matching session\n", node->nd_ID);
1452 				LEAVE(ENETUNREACH);
1453 			}
1454 
1455 			/*
1456 			 * Check the session is in the right state.
1457 			 * It needs to be in PPPOE_SINIT.
1458 			 */
1459 			sp = NG_HOOK_PRIVATE(sendhook);
1460 			if (sp->state == PPPOE_SREQ ||
1461 			    sp->state == PPPOE_CONNECTED) {
1462 				break;	/* Multiple PADO is OK. */
1463 			}
1464 			if (sp->state != PPPOE_SINIT) {
1465 				log(LOG_NOTICE, "ng_pppoe[%x]: session "
1466 				    "in wrong state\n", node->nd_ID);
1467 				LEAVE(ENETUNREACH);
1468 			}
1469 			neg = sp->neg;
1470 			/* If requested specific AC-name, check it. */
1471 			if (neg->ac_name_len) {
1472 				tag = get_tag(ph, PTT_AC_NAME);
1473 				if (!tag) {
1474 					/* No PTT_AC_NAME in PADO */
1475 					break;
1476 				}
1477 				if (neg->ac_name_len != htons(tag->tag_len) ||
1478 				    strncmp(neg->ac_name.data,
1479 				    (const char *)(tag + 1),
1480 				    neg->ac_name_len) != 0) {
1481 					break;
1482 				}
1483 			}
1484 			sp->state = PPPOE_SREQ;
1485 			ng_uncallout(&neg->handle, node);
1486 
1487 			/*
1488 			 * This is the first time we hear
1489 			 * from the server, so note it's
1490 			 * unicast address, replacing the
1491 			 * broadcast address .
1492 			 */
1493 			bcopy(wh->eh.ether_shost,
1494 				neg->pkt->pkt_header.eh.ether_dhost,
1495 				ETHER_ADDR_LEN);
1496 			neg->timeout = 0;
1497 			neg->pkt->pkt_header.ph.code = PADR_CODE;
1498 			init_tags(sp);
1499 			insert_tag(sp, utag);      	/* Host Unique */
1500 			if ((tag = get_tag(ph, PTT_AC_COOKIE)))
1501 				insert_tag(sp, tag); 	/* return cookie */
1502 			if ((tag = get_tag(ph, PTT_AC_NAME))) {
1503 				insert_tag(sp, tag); 	/* return it */
1504 				send_acname(sp, tag);
1505 			}
1506 			if ((tag = get_tag(ph, PTT_MAX_PAYL)) &&
1507 			    (privp->max_payload.data != 0))
1508 				insert_tag(sp, tag);	/* return it */
1509 			insert_tag(sp, &neg->service.hdr); /* Service */
1510 			scan_tags(sp, ph);
1511 			make_packet(sp);
1512 			sp->state = PPPOE_SREQ;
1513 			ng_callout(&neg->handle, node, sp->hook,
1514 			    PPPOE_INITIAL_TIMEOUT * hz,
1515 			    pppoe_ticker, NULL, 0);
1516 			neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1517 			m0 = m_copypacket(neg->m, M_NOWAIT);
1518 			NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1519 			break;
1520 		case	PADR_CODE:
1521 			/*
1522 			 * We are a server:
1523 			 * Use the ac_cookie tag to find the
1524 			 * hook this is in response to.
1525 			 */
1526 			utag = get_tag(ph, PTT_AC_COOKIE);
1527 			if ((utag == NULL) ||
1528 			    (ntohs(utag->tag_len) != sizeof(sp))) {
1529 				LEAVE(ENETUNREACH);
1530 			}
1531 
1532 			sendhook = pppoe_finduniq(node, utag);
1533 			if (sendhook == NULL)
1534 				LEAVE(ENETUNREACH);
1535 
1536 			/*
1537 			 * Check the session is in the right state.
1538 			 * It needs to be in PPPOE_SOFFER or PPPOE_NEWCONNECTED.
1539 			 * If the latter, then this is a retry by the client,
1540 			 * so be nice, and resend.
1541 			 */
1542 			sp = NG_HOOK_PRIVATE(sendhook);
1543 			if (sp->state == PPPOE_NEWCONNECTED) {
1544 				/*
1545 				 * Whoa! drop back to resend that PADS packet.
1546 				 * We should still have a copy of it.
1547 				 */
1548 				sp->state = PPPOE_SOFFER;
1549 			} else if (sp->state != PPPOE_SOFFER)
1550 				LEAVE (ENETUNREACH);
1551 			neg = sp->neg;
1552 			ng_uncallout(&neg->handle, node);
1553 			neg->pkt->pkt_header.ph.code = PADS_CODE;
1554 			if (sp->Session_ID == 0) {
1555 				neg->pkt->pkt_header.ph.sid =
1556 				    htons(pppoe_getnewsession(sp));
1557 			}
1558 			send_sessionid(sp);
1559 			neg->timeout = 0;
1560 			/*
1561 			 * start working out the tags to respond with.
1562 			 */
1563 			init_tags(sp);
1564 			insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1565 			if ((tag = get_tag(ph, PTT_SRV_NAME)))
1566 				insert_tag(sp, tag);/* return service */
1567 			if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1568 				insert_tag(sp, tag); /* return it */
1569 			insert_tag(sp, utag);	/* ac_cookie */
1570 			scan_tags(sp, ph);
1571 			make_packet(sp);
1572 			sp->state = PPPOE_NEWCONNECTED;
1573 
1574 			/* Send the PADS without a timeout - we're now connected. */
1575 			m0 = m_copypacket(sp->neg->m, M_NOWAIT);
1576 			NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1577 
1578 			/*
1579 			 * Having sent the last Negotiation header,
1580 			 * Set up the stored packet header to be correct for
1581 			 * the actual session. But keep the negotialtion stuff
1582 			 * around in case we need to resend this last packet.
1583 			 * We'll discard it when we move from NEWCONNECTED
1584 			 * to CONNECTED
1585 			 */
1586 			sp->pkt_hdr = neg->pkt->pkt_header;
1587 			/* Configure ethertype depending on what
1588 			 * ethertype was used at discovery phase */
1589 			if (sp->pkt_hdr.eh.ether_type ==
1590 			    ETHERTYPE_PPPOE_3COM_DISC)
1591 				sp->pkt_hdr.eh.ether_type
1592 					= ETHERTYPE_PPPOE_3COM_SESS;
1593 			else
1594 				sp->pkt_hdr.eh.ether_type
1595 					= ETHERTYPE_PPPOE_SESS;
1596 			sp->pkt_hdr.ph.code = 0;
1597 			pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1598 			break;
1599 		case	PADS_CODE:
1600 			/*
1601 			 * We are a client:
1602 			 * Use the host_uniq tag to find the hook this is in
1603 			 * response to. Take the session ID and store it away.
1604 			 * Also make sure the pre-made header is correct and
1605 			 * set us into Session mode.
1606 			 */
1607 			utag = get_tag(ph, PTT_HOST_UNIQ);
1608 			if ((utag == NULL) ||
1609 			    (ntohs(utag->tag_len) != sizeof(sp))) {
1610 				LEAVE (ENETUNREACH);
1611 			}
1612 			sendhook = pppoe_finduniq(node, utag);
1613 			if (sendhook == NULL)
1614 				LEAVE(ENETUNREACH);
1615 
1616 			/*
1617 			 * Check the session is in the right state.
1618 			 * It needs to be in PPPOE_SREQ.
1619 			 */
1620 			sp = NG_HOOK_PRIVATE(sendhook);
1621 			if (sp->state != PPPOE_SREQ)
1622 				LEAVE(ENETUNREACH);
1623 			neg = sp->neg;
1624 			ng_uncallout(&neg->handle, node);
1625 			neg->pkt->pkt_header.ph.sid = wh->ph.sid;
1626 			sp->Session_ID = ntohs(wh->ph.sid);
1627 			pppoe_addsession(sp);
1628 			send_sessionid(sp);
1629 			neg->timeout = 0;
1630 			sp->state = PPPOE_CONNECTED;
1631 			/*
1632 			 * Now we have gone to Connected mode,
1633 			 * Free all resources needed for negotiation.
1634 			 * Keep a copy of the header we will be using.
1635 			 */
1636 			sp->pkt_hdr = neg->pkt->pkt_header;
1637 			if (privp->flags & COMPAT_3COM)
1638 				sp->pkt_hdr.eh.ether_type
1639 					= ETHERTYPE_PPPOE_3COM_SESS;
1640 			else
1641 				sp->pkt_hdr.eh.ether_type
1642 					= ETHERTYPE_PPPOE_SESS;
1643 			sp->pkt_hdr.ph.code = 0;
1644 			m_freem(neg->m);
1645 			free(sp->neg, M_NETGRAPH_PPPOE);
1646 			sp->neg = NULL;
1647 			if ((tag = get_tag(ph, PTT_MAX_PAYL)) &&
1648 			    (privp->max_payload.data != 0))
1649 				send_maxp(sp, tag);
1650 			pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1651 			break;
1652 		case	PADT_CODE:
1653 			/*
1654 			 * Find matching peer/session combination.
1655 			 */
1656 			sp = pppoe_findsession(privp, wh);
1657 			if (sp == NULL)
1658 				LEAVE(ENETUNREACH);
1659 			/* Disconnect that hook. */
1660 			ng_rmhook_self(sp->hook);
1661 			break;
1662 		default:
1663 			LEAVE(EPFNOSUPPORT);
1664 		}
1665 		break;
1666 	case	ETHERTYPE_PPPOE_3COM_SESS:
1667 	case	ETHERTYPE_PPPOE_SESS:
1668 		/*
1669 		 * Find matching peer/session combination.
1670 		 */
1671 		sp = pppoe_findsession(privp, wh);
1672 		if (sp == NULL)
1673 			LEAVE (ENETUNREACH);
1674 		m_adj(m, sizeof(*wh));
1675 
1676 		/* If packet too short, dump it. */
1677 		if (m->m_pkthdr.len < length)
1678 			LEAVE(EMSGSIZE);
1679 		/* Also need to trim excess at the end */
1680 		if (m->m_pkthdr.len > length) {
1681 			m_adj(m, -((int)(m->m_pkthdr.len - length)));
1682 		}
1683 		if ( sp->state != PPPOE_CONNECTED) {
1684 			if (sp->state == PPPOE_NEWCONNECTED) {
1685 				sp->state = PPPOE_CONNECTED;
1686 				/*
1687 				 * Now we have gone to Connected mode,
1688 				 * Free all resources needed for negotiation.
1689 				 * Be paranoid about whether there may be
1690 				 * a timeout.
1691 				 */
1692 				m_freem(sp->neg->m);
1693 				ng_uncallout(&sp->neg->handle, node);
1694 				free(sp->neg, M_NETGRAPH_PPPOE);
1695 				sp->neg = NULL;
1696 			} else {
1697 				LEAVE (ENETUNREACH);
1698 			}
1699 		}
1700 		NG_FWD_NEW_DATA(error, item, sp->hook, m);
1701 		break;
1702 	default:
1703 		LEAVE(EPFNOSUPPORT);
1704 	}
1705 quit:
1706 	if (item)
1707 		NG_FREE_ITEM(item);
1708 	NG_FREE_M(m);
1709 	return (error);
1710 }
1711 
1712 /*
1713  * Receive data from debug hook and bypass it to ether.
1714  */
1715 static int
1716 ng_pppoe_rcvdata_debug(hook_p hook, item_p item)
1717 {
1718 	node_p		node = NG_HOOK_NODE(hook);
1719 	const priv_p	privp = NG_NODE_PRIVATE(node);
1720 	int		error;
1721 
1722 	CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1723 	    __func__, node->nd_ID, node, item, hook->hk_name, hook);
1724 
1725 	NG_FWD_ITEM_HOOK(error, item, privp->ethernet_hook);
1726 	privp->packets_out++;
1727 	return (error);
1728 }
1729 
1730 /*
1731  * Do local shutdown processing..
1732  * If we are a persistent device, we might refuse to go away, and
1733  * we'd only remove our links and reset ourself.
1734  */
1735 static int
1736 ng_pppoe_shutdown(node_p node)
1737 {
1738 	const priv_p privp = NG_NODE_PRIVATE(node);
1739 	int	i;
1740 
1741 	for (i = 0; i < SESSHASHSIZE; i++)
1742 	    mtx_destroy(&privp->sesshash[i].mtx);
1743 	NG_NODE_SET_PRIVATE(node, NULL);
1744 	NG_NODE_UNREF(privp->node);
1745 	free(privp, M_NETGRAPH_PPPOE);
1746 	return (0);
1747 }
1748 
1749 /*
1750  * Hook disconnection
1751  *
1752  * Clean up all dangling links and information about the session/hook.
1753  * For this type, removal of the last link destroys the node.
1754  */
1755 static int
1756 ng_pppoe_disconnect(hook_p hook)
1757 {
1758 	node_p node = NG_HOOK_NODE(hook);
1759 	priv_p privp = NG_NODE_PRIVATE(node);
1760 	sessp	sp;
1761 
1762 	if (hook == privp->debug_hook) {
1763 		privp->debug_hook = NULL;
1764 	} else if (hook == privp->ethernet_hook) {
1765 		privp->ethernet_hook = NULL;
1766 		if (NG_NODE_IS_VALID(node))
1767 			ng_rmnode_self(node);
1768 	} else {
1769 		sp = NG_HOOK_PRIVATE(hook);
1770 		if (sp->state != PPPOE_SNONE ) {
1771 			pppoe_send_event(sp, NGM_PPPOE_CLOSE);
1772 		}
1773 		/*
1774 		 * According to the spec, if we are connected,
1775 		 * we should send a DISC packet if we are shutting down
1776 		 * a session.
1777 		 */
1778 		if ((privp->ethernet_hook)
1779 		&& ((sp->state == PPPOE_CONNECTED)
1780 		 || (sp->state == PPPOE_NEWCONNECTED))) {
1781 			struct mbuf *m;
1782 
1783 			/* Generate a packet of that type. */
1784 			MGETHDR(m, M_NOWAIT, MT_DATA);
1785 			if (m == NULL)
1786 				log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
1787 				    "mbufs\n", node->nd_ID);
1788 			else {
1789 				struct pppoe_full_hdr *wh;
1790 				struct pppoe_tag *tag;
1791 				int	msglen = strlen(SIGNOFF);
1792 				int	error = 0;
1793 
1794 				m->m_pkthdr.rcvif = NULL;
1795 				m->m_pkthdr.len = m->m_len = sizeof(*wh);
1796 				wh = mtod(m, struct pppoe_full_hdr *);
1797 				bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1798 
1799 				/* Revert the stored header to DISC/PADT mode. */
1800 				wh->ph.code = PADT_CODE;
1801 				/*
1802 				 * Configure ethertype depending on what
1803 				 * was used during sessions stage.
1804 				 */
1805 				if (wh->eh.ether_type ==
1806 				    ETHERTYPE_PPPOE_3COM_SESS)
1807 					wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
1808 				else
1809 					wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1810 				/*
1811 				 * Add a General error message and adjust
1812 				 * sizes.
1813 				 */
1814 				tag = (void *)(&wh->ph + 1);
1815 				tag->tag_type = PTT_GEN_ERR;
1816 				tag->tag_len = htons((u_int16_t)msglen);
1817 				strncpy((char *)(tag + 1), SIGNOFF, msglen);
1818 				m->m_pkthdr.len = (m->m_len += sizeof(*tag) +
1819 				    msglen);
1820 				wh->ph.length = htons(sizeof(*tag) + msglen);
1821 				NG_SEND_DATA_ONLY(error,
1822 					privp->ethernet_hook, m);
1823 			}
1824 		}
1825 		if (sp->state == PPPOE_LISTENING)
1826 			LIST_REMOVE(sp, sessions);
1827 		else if (sp->Session_ID)
1828 			pppoe_delsession(sp);
1829 		/*
1830 		 * As long as we have somewhere to store the timeout handle,
1831 		 * we may have a timeout pending.. get rid of it.
1832 		 */
1833 		if (sp->neg) {
1834 			ng_uncallout(&sp->neg->handle, node);
1835 			if (sp->neg->m)
1836 				m_freem(sp->neg->m);
1837 			free(sp->neg, M_NETGRAPH_PPPOE);
1838 		}
1839 		free(sp, M_NETGRAPH_PPPOE);
1840 		NG_HOOK_SET_PRIVATE(hook, NULL);
1841 	}
1842 	if ((NG_NODE_NUMHOOKS(node) == 0) &&
1843 	    (NG_NODE_IS_VALID(node)))
1844 		ng_rmnode_self(node);
1845 	return (0);
1846 }
1847 
1848 /*
1849  * Timeouts come here.
1850  */
1851 static void
1852 pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2)
1853 {
1854 	priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
1855 	sessp	sp = NG_HOOK_PRIVATE(hook);
1856 	negp	neg = sp->neg;
1857 	struct mbuf *m0 = NULL;
1858 	int	error = 0;
1859 
1860 	CTR6(KTR_NET, "%20s: node [%x] (%p) hook \"%s\" (%p) session %d",
1861 	    __func__, node->nd_ID, node, hook->hk_name, hook, sp->Session_ID);
1862 	switch(sp->state) {
1863 		/*
1864 		 * Resend the last packet, using an exponential backoff.
1865 		 * After a period of time, stop growing the backoff,
1866 		 * And either leave it, or revert to the start.
1867 		 */
1868 	case	PPPOE_SINIT:
1869 	case	PPPOE_SREQ:
1870 		/* Timeouts on these produce resends. */
1871 		m0 = m_copypacket(sp->neg->m, M_NOWAIT);
1872 		NG_SEND_DATA_ONLY( error, privp->ethernet_hook, m0);
1873 		ng_callout(&neg->handle, node, hook, neg->timeout * hz,
1874 		    pppoe_ticker, NULL, 0);
1875 		if ((neg->timeout <<= 1) > PPPOE_TIMEOUT_LIMIT) {
1876 			if (sp->state == PPPOE_SREQ) {
1877 				/* Revert to SINIT mode. */
1878 				pppoe_start(sp);
1879 			} else {
1880 				neg->timeout = PPPOE_TIMEOUT_LIMIT;
1881 			}
1882 		}
1883 		break;
1884 	case	PPPOE_PRIMED:
1885 	case	PPPOE_SOFFER:
1886 		/* A timeout on these says "give up" */
1887 		ng_rmhook_self(hook);
1888 		break;
1889 	default:
1890 		/* Timeouts have no meaning in other states. */
1891 		log(LOG_NOTICE, "ng_pppoe[%x]: unexpected timeout\n",
1892 		    node->nd_ID);
1893 	}
1894 }
1895 
1896 /*
1897  * Parse an incoming packet to see if any tags should be copied to the
1898  * output packet. Don't do any tags that have been handled in the main
1899  * state machine.
1900  */
1901 static const struct pppoe_tag*
1902 scan_tags(sessp	sp, const struct pppoe_hdr* ph)
1903 {
1904 	const char *const end = (const char *)next_tag(ph);
1905 	const char *ptn;
1906 	const struct pppoe_tag *pt = (const void *)(ph + 1);
1907 
1908 	/*
1909 	 * Keep processing tags while a tag header will still fit.
1910 	 */
1911 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1912 
1913 	while((const char*)(pt + 1) <= end) {
1914 		/*
1915 		 * If the tag data would go past the end of the packet, abort.
1916 		 */
1917 		ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
1918 		if(ptn > end)
1919 			return NULL;
1920 
1921 		switch (pt->tag_type) {
1922 		case	PTT_RELAY_SID:
1923 			insert_tag(sp, pt);
1924 			break;
1925 		case	PTT_EOL:
1926 			return NULL;
1927 		case	PTT_SRV_NAME:
1928 		case	PTT_AC_NAME:
1929 		case	PTT_HOST_UNIQ:
1930 		case	PTT_AC_COOKIE:
1931 		case	PTT_VENDOR:
1932 		case	PTT_SRV_ERR:
1933 		case	PTT_SYS_ERR:
1934 		case	PTT_GEN_ERR:
1935 		case	PTT_MAX_PAYL:
1936 			break;
1937 		}
1938 		pt = (const struct pppoe_tag*)ptn;
1939 	}
1940 	return NULL;
1941 }
1942 
1943 static	int
1944 pppoe_send_event(sessp sp, enum cmd cmdid)
1945 {
1946 	int error;
1947 	struct ng_mesg *msg;
1948 	struct ngpppoe_sts *sts;
1949 
1950 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1951 
1952 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, cmdid,
1953 			sizeof(struct ngpppoe_sts), M_NOWAIT);
1954 	if (msg == NULL)
1955 		return (ENOMEM);
1956 	sts = (struct ngpppoe_sts *)msg->data;
1957 	strncpy(sts->hook, NG_HOOK_NAME(sp->hook), NG_HOOKSIZ);
1958 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1959 	return (error);
1960 }
1961