xref: /freebsd/sys/netgraph/ng_pppoe.c (revision f39bffc62c1395bde25d152c7f68fdf7cbaab414)
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         {
179 	  NGM_PPPOE_COOKIE,
180 	  NGM_PPPOE_SEND_HURL,
181 	  "send_hurl",
182 	  &ngpppoe_init_data_state_type,
183 	  NULL
184         },
185         {
186 	  NGM_PPPOE_COOKIE,
187 	  NGM_PPPOE_SEND_MOTM,
188 	  "send_motm",
189 	  &ngpppoe_init_data_state_type,
190 	  NULL
191         },
192 	{ 0 }
193 };
194 
195 /* Netgraph node type descriptor */
196 static struct ng_type typestruct = {
197 	.version =	NG_ABI_VERSION,
198 	.name =		NG_PPPOE_NODE_TYPE,
199 	.constructor =	ng_pppoe_constructor,
200 	.rcvmsg =	ng_pppoe_rcvmsg,
201 	.shutdown =	ng_pppoe_shutdown,
202 	.newhook =	ng_pppoe_newhook,
203 	.connect =	ng_pppoe_connect,
204 	.rcvdata =	ng_pppoe_rcvdata,
205 	.disconnect =	ng_pppoe_disconnect,
206 	.cmdlist =	ng_pppoe_cmds,
207 };
208 NETGRAPH_INIT(pppoe, &typestruct);
209 
210 /*
211  * States for the session state machine.
212  * These have no meaning if there is no hook attached yet.
213  */
214 enum state {
215     PPPOE_SNONE=0,	/* [both] Initial state */
216     PPPOE_LISTENING,	/* [Daemon] Listening for discover initiation pkt */
217     PPPOE_SINIT,	/* [Client] Sent discovery initiation */
218     PPPOE_PRIMED,	/* [Server] Awaiting PADI from daemon */
219     PPPOE_SOFFER,	/* [Server] Sent offer message  (got PADI)*/
220     PPPOE_SREQ,		/* [Client] Sent a Request */
221     PPPOE_NEWCONNECTED,	/* [Server] Connection established, No data received */
222     PPPOE_CONNECTED,	/* [Both] Connection established, Data received */
223     PPPOE_DEAD		/* [Both] */
224 };
225 
226 #define NUMTAGS 20 /* number of tags we are set up to work with */
227 
228 /*
229  * Information we store for each hook on each node for negotiating the
230  * session. The mbuf and cluster are freed once negotiation has completed.
231  * The whole negotiation block is then discarded.
232  */
233 
234 struct sess_neg {
235 	struct mbuf 		*m; /* holds cluster with last sent packet */
236 	union	packet		*pkt; /* points within the above cluster */
237 	struct callout		handle;   /* see timeout(9) */
238 	u_int			timeout; /* 0,1,2,4,8,16 etc. seconds */
239 	u_int			numtags;
240 	const struct pppoe_tag	*tags[NUMTAGS];
241 	u_int			service_len;
242 	u_int			ac_name_len;
243 	u_int			host_uniq_len;
244 
245 	struct datatag		service;
246 	struct datatag		ac_name;
247 	struct datatag		host_uniq;
248 };
249 typedef struct sess_neg *negp;
250 
251 /*
252  * Session information that is needed after connection.
253  */
254 struct sess_con {
255 	hook_p  		hook;
256 	uint16_t		Session_ID;
257 	enum state		state;
258 	ng_ID_t			creator;	/* who to notify */
259 	struct pppoe_full_hdr	pkt_hdr;	/* used when connected */
260 	negp			neg;		/* used when negotiating */
261 	LIST_ENTRY(sess_con)	sessions;
262 };
263 typedef struct sess_con *sessp;
264 
265 #define SESSHASHSIZE	0x0100
266 #define SESSHASH(x)	(((x) ^ ((x) >> 8)) & (SESSHASHSIZE - 1))
267 
268 struct sess_hash_entry {
269 	struct mtx	mtx;
270 	LIST_HEAD(hhead, sess_con) head;
271 };
272 
273 /*
274  * Information we store for each node
275  */
276 struct PPPoE {
277 	node_p		node;		/* back pointer to node */
278 	hook_p  	ethernet_hook;
279 	hook_p  	debug_hook;
280 	u_int   	packets_in;	/* packets in from ethernet */
281 	u_int   	packets_out;	/* packets out towards ethernet */
282 	uint32_t	flags;
283 #define	COMPAT_3COM	0x00000001
284 #define	COMPAT_DLINK	0x00000002
285 	struct ether_header	eh;
286 	LIST_HEAD(, sess_con) listeners;
287 	struct sess_hash_entry	sesshash[SESSHASHSIZE];
288 	struct maxptag	max_payload;	/* PPP-Max-Payload (RFC4638) */
289 };
290 typedef struct PPPoE *priv_p;
291 
292 union uniq {
293 	char bytes[sizeof(void *)];
294 	void *pointer;
295 };
296 
297 #define	LEAVE(x) do { error = x; goto quit; } while(0)
298 static void	pppoe_start(sessp sp);
299 static void	pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2);
300 static const	struct pppoe_tag *scan_tags(sessp sp,
301 			const struct pppoe_hdr* ph);
302 static	int	pppoe_send_event(sessp sp, enum cmd cmdid);
303 
304 /*************************************************************************
305  * Some basic utilities  from the Linux version with author's permission.*
306  * Author:	Michal Ostrowski <mostrows@styx.uwaterloo.ca>		 *
307  ************************************************************************/
308 
309 
310 
311 /*
312  * Return the location where the next tag can be put
313  */
314 static __inline const struct pppoe_tag*
315 next_tag(const struct pppoe_hdr* ph)
316 {
317 	return (const struct pppoe_tag*)(((const char*)(ph + 1))
318 	    + ntohs(ph->length));
319 }
320 
321 /*
322  * Look for a tag of a specific type.
323  * Don't trust any length the other end says,
324  * but assume we already sanity checked ph->length.
325  */
326 static const struct pppoe_tag*
327 get_tag(const struct pppoe_hdr* ph, uint16_t idx)
328 {
329 	const char *const end = (const char *)next_tag(ph);
330 	const struct pppoe_tag *pt = (const void *)(ph + 1);
331 	const char *ptn;
332 
333 	/*
334 	 * Keep processing tags while a tag header will still fit.
335 	 */
336 	while((const char*)(pt + 1) <= end) {
337 		/*
338 		 * If the tag data would go past the end of the packet, abort.
339 		 */
340 		ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
341 		if (ptn > end) {
342 			CTR2(KTR_NET, "%20s: invalid length for tag %d",
343 			    __func__, idx);
344 			return (NULL);
345 		}
346 		if (pt->tag_type == idx) {
347 			CTR2(KTR_NET, "%20s: found tag %d", __func__, idx);
348 			return (pt);
349 		}
350 
351 		pt = (const struct pppoe_tag*)ptn;
352 	}
353 
354 	CTR2(KTR_NET, "%20s: not found tag %d", __func__, idx);
355 	return (NULL);
356 }
357 
358 /**************************************************************************
359  * Inlines to initialise or add tags to a session's tag list.
360  **************************************************************************/
361 /*
362  * Initialise the session's tag list.
363  */
364 static void
365 init_tags(sessp sp)
366 {
367 	KASSERT(sp->neg != NULL, ("%s: no neg", __func__));
368 	sp->neg->numtags = 0;
369 }
370 
371 static void
372 insert_tag(sessp sp, const struct pppoe_tag *tp)
373 {
374 	negp neg = sp->neg;
375 	int i;
376 
377 	KASSERT(neg != NULL, ("%s: no neg", __func__));
378 	if ((i = neg->numtags++) < NUMTAGS) {
379 		neg->tags[i] = tp;
380 	} else {
381 		log(LOG_NOTICE, "ng_pppoe: asked to add too many tags to "
382 		    "packet\n");
383 		neg->numtags--;
384 	}
385 }
386 
387 /*
388  * Make up a packet, using the tags filled out for the session.
389  *
390  * Assume that the actual pppoe header and ethernet header
391  * are filled out externally to this routine.
392  * Also assume that neg->wh points to the correct
393  * location at the front of the buffer space.
394  */
395 static void
396 make_packet(sessp sp) {
397 	struct pppoe_full_hdr *wh = &sp->neg->pkt->pkt_header;
398 	const struct pppoe_tag **tag;
399 	char *dp;
400 	int count;
401 	int tlen;
402 	uint16_t length = 0;
403 
404 	KASSERT((sp->neg != NULL) && (sp->neg->m != NULL),
405 	    ("%s: called from wrong state", __func__));
406 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
407 
408 	dp = (char *)(&wh->ph + 1);
409 	for (count = 0, tag = sp->neg->tags;
410 	    ((count < sp->neg->numtags) && (count < NUMTAGS));
411 	    tag++, count++) {
412 		tlen = ntohs((*tag)->tag_len) + sizeof(**tag);
413 		if ((length + tlen) > (ETHER_MAX_LEN - 4 - sizeof(*wh))) {
414 			log(LOG_NOTICE, "ng_pppoe: tags too long\n");
415 			sp->neg->numtags = count;
416 			break;	/* XXX chop off what's too long */
417 		}
418 		bcopy(*tag, (char *)dp, tlen);
419 		length += tlen;
420 		dp += tlen;
421 	}
422  	wh->ph.length = htons(length);
423 	sp->neg->m->m_len = length + sizeof(*wh);
424 	sp->neg->m->m_pkthdr.len = length + sizeof(*wh);
425 }
426 
427 /**************************************************************************
428  * Routines to match a service.						  *
429  **************************************************************************/
430 
431 /*
432  * Find a hook that has a service string that matches that
433  * we are seeking. For now use a simple string.
434  * In the future we may need something like regexp().
435  *
436  * Null string is a wildcard (ANY service), according to RFC2516.
437  * And historical FreeBSD wildcard is also "*".
438  */
439 
440 static hook_p
441 pppoe_match_svc(node_p node, const struct pppoe_tag *tag)
442 {
443 	const priv_p privp = NG_NODE_PRIVATE(node);
444 	sessp sp;
445 
446 	LIST_FOREACH(sp, &privp->listeners, sessions) {
447 		negp neg = sp->neg;
448 
449 		/* Empty Service-Name matches any service. */
450 		if (neg->service_len == 0)
451 			break;
452 
453 		/* Special case for a blank or "*" service name (wildcard). */
454 		if (neg->service_len == 1 && neg->service.data[0] == '*')
455 			break;
456 
457 		/* If the lengths don't match, that aint it. */
458 		if (neg->service_len != ntohs(tag->tag_len))
459 			continue;
460 
461 		if (strncmp((const char *)(tag + 1), neg->service.data,
462 		    ntohs(tag->tag_len)) == 0)
463 			break;
464 	}
465 	CTR3(KTR_NET, "%20s: matched %p for %s", __func__,
466 	    sp?sp->hook:NULL, (const char *)(tag + 1));
467 
468 	return (sp?sp->hook:NULL);
469 }
470 
471 /*
472  * Broadcast the PADI packet in m0 to all listening hooks.
473  * This routine is called when a PADI with empty Service-Name
474  * tag is received. Client should receive PADOs with all
475  * available services.
476  */
477 static int
478 pppoe_broadcast_padi(node_p node, struct mbuf *m0)
479 {
480 	const priv_p privp = NG_NODE_PRIVATE(node);
481 	sessp sp;
482 	int error = 0;
483 
484 	LIST_FOREACH(sp, &privp->listeners, sessions) {
485 		struct mbuf *m;
486 
487 		m = m_dup(m0, M_NOWAIT);
488 		if (m == NULL)
489 			return (ENOMEM);
490 		NG_SEND_DATA_ONLY(error, sp->hook, m);
491 		if (error)
492 			return (error);
493 	}
494 
495 	return (0);
496 }
497 
498 /*
499  * Find a hook, which name equals to given service.
500  */
501 static hook_p
502 pppoe_find_svc(node_p node, const char *svc_name, int svc_len)
503 {
504 	const priv_p privp = NG_NODE_PRIVATE(node);
505 	sessp sp;
506 
507 	LIST_FOREACH(sp, &privp->listeners, sessions) {
508 		negp neg = sp->neg;
509 
510 		if (neg->service_len == svc_len &&
511 		    strncmp(svc_name, neg->service.data, svc_len) == 0)
512 			return (sp->hook);
513 	}
514 
515 	return (NULL);
516 }
517 
518 /**************************************************************************
519  * Routines to find a particular session that matches an incoming packet. *
520  **************************************************************************/
521 /* Find free session and add to hash. */
522 static uint16_t
523 pppoe_getnewsession(sessp sp)
524 {
525 	const priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
526 	static uint16_t pppoe_sid = 1;
527 	sessp	tsp;
528 	uint16_t val, hash;
529 
530 restart:
531 	/* Atomicity is not needed here as value will be checked. */
532 	val = pppoe_sid++;
533 	/* Spec says 0xFFFF is reserved, also don't use 0x0000. */
534 	if (val == 0xffff || val == 0x0000)
535 		val = pppoe_sid = 1;
536 
537 	/* Check it isn't already in use. */
538 	hash = SESSHASH(val);
539 	mtx_lock(&privp->sesshash[hash].mtx);
540 	LIST_FOREACH(tsp, &privp->sesshash[hash].head, sessions) {
541 		if (tsp->Session_ID == val)
542 			break;
543 	}
544 	if (!tsp) {
545 		sp->Session_ID = val;
546 		LIST_INSERT_HEAD(&privp->sesshash[hash].head, sp, sessions);
547 	}
548 	mtx_unlock(&privp->sesshash[hash].mtx);
549 	if (tsp)
550 		goto restart;
551 
552 	CTR2(KTR_NET, "%20s: new sid %d", __func__, val);
553 
554 	return (val);
555 }
556 
557 /* Add specified session to hash. */
558 static void
559 pppoe_addsession(sessp sp)
560 {
561 	const priv_p	privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
562 	uint16_t	hash = SESSHASH(sp->Session_ID);
563 
564 	mtx_lock(&privp->sesshash[hash].mtx);
565 	LIST_INSERT_HEAD(&privp->sesshash[hash].head, sp, sessions);
566 	mtx_unlock(&privp->sesshash[hash].mtx);
567 }
568 
569 /* Delete specified session from hash. */
570 static void
571 pppoe_delsession(sessp sp)
572 {
573 	const priv_p	privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
574 	uint16_t	hash = SESSHASH(sp->Session_ID);
575 
576 	mtx_lock(&privp->sesshash[hash].mtx);
577 	LIST_REMOVE(sp, sessions);
578 	mtx_unlock(&privp->sesshash[hash].mtx);
579 }
580 
581 /* Find matching peer/session combination. */
582 static sessp
583 pppoe_findsession(priv_p privp, const struct pppoe_full_hdr *wh)
584 {
585 	uint16_t 	session = ntohs(wh->ph.sid);
586 	uint16_t	hash = SESSHASH(session);
587 	sessp		sp = NULL;
588 
589 	mtx_lock(&privp->sesshash[hash].mtx);
590 	LIST_FOREACH(sp, &privp->sesshash[hash].head, sessions) {
591 		if (sp->Session_ID == session &&
592 		    bcmp(sp->pkt_hdr.eh.ether_dhost,
593 		     wh->eh.ether_shost, ETHER_ADDR_LEN) == 0) {
594 			break;
595 		}
596 	}
597 	mtx_unlock(&privp->sesshash[hash].mtx);
598 	CTR3(KTR_NET, "%20s: matched %p for %d", __func__, sp?sp->hook:NULL,
599 	    session);
600 
601 	return (sp);
602 }
603 
604 static hook_p
605 pppoe_finduniq(node_p node, const struct pppoe_tag *tag)
606 {
607 	hook_p	hook = NULL;
608 	sessp	sp;
609 
610 	/* Cycle through all known hooks. */
611 	LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
612 		/* Skip any nonsession hook. */
613 		if (NG_HOOK_PRIVATE(hook) == NULL)
614 			continue;
615 		sp = NG_HOOK_PRIVATE(hook);
616 		/* Skip already connected sessions. */
617 		if (sp->neg == NULL)
618 			continue;
619 		if (sp->neg->host_uniq_len == ntohs(tag->tag_len) &&
620 		    bcmp(sp->neg->host_uniq.data, (const char *)(tag + 1),
621 		     sp->neg->host_uniq_len) == 0)
622 			break;
623 	}
624 	CTR3(KTR_NET, "%20s: matched %p for %p", __func__, hook, sp);
625 
626 	return (hook);
627 }
628 
629 static hook_p
630 pppoe_findcookie(node_p node, const struct pppoe_tag *tag)
631 {
632 	hook_p	hook = NULL;
633 	union uniq cookie;
634 
635 	bcopy(tag + 1, cookie.bytes, sizeof(void *));
636 	/* Cycle through all known hooks. */
637 	LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
638 		/* Skip any nonsession hook. */
639 		if (NG_HOOK_PRIVATE(hook) == NULL)
640 			continue;
641 		if (cookie.pointer == NG_HOOK_PRIVATE(hook))
642 			break;
643 	}
644 	CTR3(KTR_NET, "%20s: matched %p for %p", __func__, hook, cookie.pointer);
645 
646 	return (hook);
647 }
648 
649 /**************************************************************************
650  * Start of Netgraph entrypoints.					  *
651  **************************************************************************/
652 
653 /*
654  * Allocate the private data structure and link it with node.
655  */
656 static int
657 ng_pppoe_constructor(node_p node)
658 {
659 	priv_p	privp;
660 	int	i;
661 
662 	/* Initialize private descriptor. */
663 	privp = malloc(sizeof(*privp), M_NETGRAPH_PPPOE, M_WAITOK | M_ZERO);
664 
665 	/* Link structs together; this counts as our one reference to *node. */
666 	NG_NODE_SET_PRIVATE(node, privp);
667 	privp->node = node;
668 
669 	/* Initialize to standard mode. */
670 	memset(&privp->eh.ether_dhost, 0xff, ETHER_ADDR_LEN);
671 	privp->eh.ether_type = ETHERTYPE_PPPOE_DISC;
672 
673 	LIST_INIT(&privp->listeners);
674 	for (i = 0; i < SESSHASHSIZE; i++) {
675 	    mtx_init(&privp->sesshash[i].mtx, "PPPoE hash mutex", NULL, MTX_DEF);
676 	    LIST_INIT(&privp->sesshash[i].head);
677 	}
678 
679 	CTR3(KTR_NET, "%20s: created node [%x] (%p)",
680 	    __func__, node->nd_ID, node);
681 
682 	return (0);
683 }
684 
685 /*
686  * Give our ok for a hook to be added...
687  * point the hook's private info to the hook structure.
688  *
689  * The following hook names are special:
690  *  "ethernet":  the hook that should be connected to a NIC.
691  *  "debug":	copies of data sent out here  (when I write the code).
692  * All other hook names need only be unique. (the framework checks this).
693  */
694 static int
695 ng_pppoe_newhook(node_p node, hook_p hook, const char *name)
696 {
697 	const priv_p privp = NG_NODE_PRIVATE(node);
698 	sessp sp;
699 
700 	if (strcmp(name, NG_PPPOE_HOOK_ETHERNET) == 0) {
701 		privp->ethernet_hook = hook;
702 		NG_HOOK_SET_RCVDATA(hook, ng_pppoe_rcvdata_ether);
703 	} else if (strcmp(name, NG_PPPOE_HOOK_DEBUG) == 0) {
704 		privp->debug_hook = hook;
705 		NG_HOOK_SET_RCVDATA(hook, ng_pppoe_rcvdata_debug);
706 	} else {
707 		/*
708 		 * Any other unique name is OK.
709 		 * The infrastructure has already checked that it's unique,
710 		 * so just allocate it and hook it in.
711 		 */
712 		sp = malloc(sizeof(*sp), M_NETGRAPH_PPPOE, M_NOWAIT | M_ZERO);
713 		if (sp == NULL)
714 			return (ENOMEM);
715 
716 		NG_HOOK_SET_PRIVATE(hook, sp);
717 		sp->hook = hook;
718 	}
719 	CTR5(KTR_NET, "%20s: node [%x] (%p) connected hook %s (%p)",
720 	    __func__, node->nd_ID, node, name, hook);
721 
722 	return(0);
723 }
724 
725 /*
726  * Hook has been added successfully. Request the MAC address of
727  * the underlying Ethernet node.
728  */
729 static int
730 ng_pppoe_connect(hook_p hook)
731 {
732 	const priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
733 	struct ng_mesg *msg;
734 	int error;
735 
736 	if (hook != privp->ethernet_hook)
737 		return (0);
738 
739 	/*
740 	 * If this is Ethernet hook, then request MAC address
741 	 * from our downstream.
742 	 */
743 	NG_MKMESSAGE(msg, NGM_ETHER_COOKIE, NGM_ETHER_GET_ENADDR, 0, M_NOWAIT);
744 	if (msg == NULL)
745 		return (ENOBUFS);
746 
747 	/*
748 	 * Our hook and peer hook have HK_INVALID flag set,
749 	 * so we can't use NG_SEND_MSG_HOOK() macro here.
750 	 */
751 	NG_SEND_MSG_ID(error, privp->node, msg,
752 	    NG_NODE_ID(NG_PEER_NODE(privp->ethernet_hook)),
753 	    NG_NODE_ID(privp->node));
754 
755 	return (error);
756 }
757 /*
758  * Get a netgraph control message.
759  * Check it is one we understand. If needed, send a response.
760  * We sometimes save the address for an async action later.
761  * Always free the message.
762  */
763 static int
764 ng_pppoe_rcvmsg(node_p node, item_p item, hook_p lasthook)
765 {
766 	priv_p privp = NG_NODE_PRIVATE(node);
767 	struct ngpppoe_init_data *ourmsg = NULL;
768 	struct ng_mesg *resp = NULL;
769 	int error = 0;
770 	hook_p hook = NULL;
771 	sessp sp = NULL;
772 	negp neg = NULL;
773 	struct ng_mesg *msg;
774 
775 	NGI_GET_MSG(item, msg);
776 	CTR5(KTR_NET, "%20s: node [%x] (%p) got message %d with cookie %d",
777 	    __func__, node->nd_ID, node, msg->header.cmd,
778 	    msg->header.typecookie);
779 
780 	/* Deal with message according to cookie and command. */
781 	switch (msg->header.typecookie) {
782 	case NGM_PPPOE_COOKIE:
783 		switch (msg->header.cmd) {
784 		case NGM_PPPOE_CONNECT:
785 		case NGM_PPPOE_LISTEN:
786 		case NGM_PPPOE_OFFER:
787 		case NGM_PPPOE_SERVICE:
788 		case NGM_PPPOE_SEND_HURL:
789 		case NGM_PPPOE_SEND_MOTM:
790 			ourmsg = (struct ngpppoe_init_data *)msg->data;
791 			if (msg->header.arglen < sizeof(*ourmsg)) {
792 				log(LOG_ERR, "ng_pppoe[%x]: init data too "
793 				    "small\n", node->nd_ID);
794 				LEAVE(EMSGSIZE);
795 			}
796 			if (msg->header.cmd == NGM_PPPOE_SEND_HURL ||
797 			    msg->header.cmd == NGM_PPPOE_SEND_MOTM) {
798 				if (msg->header.arglen - sizeof(*ourmsg) >
799 				    PPPOE_PADM_VALUE_SIZE) {
800 					log(LOG_ERR, "ng_pppoe[%x]: message "
801 					    "too big\n", node->nd_ID);
802 					LEAVE(EMSGSIZE);
803 				}
804 			} else {
805 				if (msg->header.arglen - sizeof(*ourmsg) >
806 				    PPPOE_SERVICE_NAME_SIZE) {
807 					log(LOG_ERR, "ng_pppoe[%x]: service name "
808 					    "too big\n", node->nd_ID);
809 					LEAVE(EMSGSIZE);
810 				}
811 			}
812 			if (msg->header.arglen - sizeof(*ourmsg) <
813 			    ourmsg->data_len) {
814 				log(LOG_ERR, "ng_pppoe[%x]: init data has bad "
815 				    "length, %d should be %zd\n", node->nd_ID,
816 				    ourmsg->data_len,
817 				    msg->header.arglen - sizeof (*ourmsg));
818 				LEAVE(EMSGSIZE);
819 			}
820 
821 			/* Make sure strcmp will terminate safely. */
822 			ourmsg->hook[sizeof(ourmsg->hook) - 1] = '\0';
823 
824 			/* Find hook by name. */
825 			hook = ng_findhook(node, ourmsg->hook);
826 			if (hook == NULL)
827 				LEAVE(ENOENT);
828 
829 			sp = NG_HOOK_PRIVATE(hook);
830 			if (sp == NULL)
831 				LEAVE(EINVAL);
832 
833 			if (msg->header.cmd == NGM_PPPOE_LISTEN) {
834 				/*
835 				 * Ensure we aren't already listening for this
836 				 * service.
837 				 */
838 				if (pppoe_find_svc(node, ourmsg->data,
839 				    ourmsg->data_len) != NULL)
840 					LEAVE(EEXIST);
841 			}
842 
843 			/*
844 			 * PPPOE_SERVICE advertisements are set up
845 			 * on sessions that are in PRIMED state.
846 			 */
847 			if (msg->header.cmd == NGM_PPPOE_SERVICE)
848 				break;
849 
850 			/*
851 			 * PADM messages are set up on active sessions.
852 			 */
853 			if (msg->header.cmd == NGM_PPPOE_SEND_HURL ||
854 			    msg->header.cmd == NGM_PPPOE_SEND_MOTM) {
855 				if (sp->state != PPPOE_NEWCONNECTED &&
856 				    sp->state != PPPOE_CONNECTED) {
857 					log(LOG_NOTICE, "ng_pppoe[%x]: session is not "
858 					    "active\n", node->nd_ID);
859 					LEAVE(EISCONN);
860 				}
861 				break;
862 			}
863 
864 			if (sp->state != PPPOE_SNONE) {
865 				log(LOG_NOTICE, "ng_pppoe[%x]: Session already "
866 				    "active\n", node->nd_ID);
867 				LEAVE(EISCONN);
868 			}
869 
870 			/*
871 			 * Set up prototype header.
872 			 */
873 			neg = malloc(sizeof(*neg), M_NETGRAPH_PPPOE,
874 			    M_NOWAIT | M_ZERO);
875 
876 			if (neg == NULL)
877 				LEAVE(ENOMEM);
878 
879 			neg->m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
880 			if (neg->m == NULL) {
881 				free(neg, M_NETGRAPH_PPPOE);
882 				LEAVE(ENOBUFS);
883 			}
884 			neg->m->m_pkthdr.rcvif = NULL;
885 			sp->neg = neg;
886 			ng_callout_init(&neg->handle);
887 			neg->m->m_len = sizeof(struct pppoe_full_hdr);
888 			neg->pkt = mtod(neg->m, union packet*);
889 			memcpy((void *)&neg->pkt->pkt_header.eh,
890 			    &privp->eh, sizeof(struct ether_header));
891 			neg->pkt->pkt_header.ph.ver = 0x1;
892 			neg->pkt->pkt_header.ph.type = 0x1;
893 			neg->pkt->pkt_header.ph.sid = 0x0000;
894 			neg->timeout = 0;
895 
896 			sp->creator = NGI_RETADDR(item);
897 		}
898 		switch (msg->header.cmd) {
899 		case NGM_PPPOE_GET_STATUS:
900 		    {
901 			struct ngpppoestat *stats;
902 
903 			NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT);
904 			if (!resp)
905 				LEAVE(ENOMEM);
906 
907 			stats = (struct ngpppoestat *) resp->data;
908 			stats->packets_in = privp->packets_in;
909 			stats->packets_out = privp->packets_out;
910 			break;
911 		    }
912 		case NGM_PPPOE_CONNECT:
913 		    {
914 			/*
915 			 * Check the hook exists and is Uninitialised.
916 			 * Send a PADI request, and start the timeout logic.
917 			 * Store the originator of this message so we can send
918 			 * a success or fail message to them later.
919 			 * Move the session to SINIT.
920 			 * Set up the session to the correct state and
921 			 * start it.
922 			 */
923 			int	acnpos, acnlen = 0, acnsep = 0;
924 			int	hupos, hulen = 0, husep = 0;
925 			int	i, srvpos, srvlen;
926 			acnpos = 0;
927 			for (i = 0; i < ourmsg->data_len; i++) {
928 				if (ourmsg->data[i] == '\\') {
929 					acnlen = i;
930 					acnsep = 1;
931 					break;
932 				}
933 			}
934 			hupos = acnlen + acnsep;
935 			for (i = hupos; i < ourmsg->data_len; i++) {
936 				if (ourmsg->data[i] == '|') {
937 					hulen = i - hupos;
938 					husep = 1;
939 					break;
940 				}
941 			}
942 			srvpos = hupos + hulen + husep;
943 			srvlen = ourmsg->data_len - srvpos;
944 
945 			bcopy(ourmsg->data + acnpos, neg->ac_name.data, acnlen);
946 			neg->ac_name_len = acnlen;
947 
948 			neg->host_uniq.hdr.tag_type = PTT_HOST_UNIQ;
949 			if (hulen == 0) {
950 				/* Not provided, generate one */
951 				neg->host_uniq.hdr.tag_len = htons(sizeof(sp));
952 				bcopy(&sp, neg->host_uniq.data, sizeof(sp));
953 				neg->host_uniq_len = sizeof(sp);
954 			} else if (hulen > 2 && ourmsg->data[hupos] == '0' &&
955 			  ourmsg->data[hupos + 1] == 'x' && hulen % 2 == 0) {
956 				/* Hex encoded */
957 				static const char hexdig[16] = "0123456789abcdef";
958 				int j;
959 
960 				neg->host_uniq.hdr.tag_len = htons((uint16_t)(hulen / 2 - 1));
961 				for (i = 0; i < hulen - 2; i++) {
962 					for (j = 0;
963 					     j < 16 &&
964 					     ourmsg->data[hupos + 2 + i] != hexdig[j];
965 					     j++);
966 					if (j == 16)
967 						LEAVE(EINVAL);
968 					if (i % 2 == 0)
969 						neg->host_uniq.data[i / 2] = j << 4;
970 					else
971 						neg->host_uniq.data[i / 2] |= j;
972 				}
973 				neg->host_uniq_len = hulen / 2 - 1;
974 			} else {
975 				/* Plain string */
976 				neg->host_uniq.hdr.tag_len = htons((uint16_t)hulen);
977 				bcopy(ourmsg->data + hupos, neg->host_uniq.data, hulen);
978 				neg->host_uniq_len = hulen;
979 			}
980 
981 			neg->service.hdr.tag_type = PTT_SRV_NAME;
982 			neg->service.hdr.tag_len = htons((uint16_t)srvlen);
983 			bcopy(ourmsg->data + srvpos, neg->service.data, srvlen);
984 			neg->service_len = srvlen;
985 			pppoe_start(sp);
986 			break;
987 		    }
988 		case NGM_PPPOE_LISTEN:
989 			/*
990 			 * Check the hook exists and is Uninitialised.
991 			 * Install the service matching string.
992 			 * Store the originator of this message so we can send
993 			 * a success or fail message to them later.
994 			 * Move the hook to 'LISTENING'
995 			 */
996 			neg->service.hdr.tag_type = PTT_SRV_NAME;
997 			neg->service.hdr.tag_len =
998 			    htons((uint16_t)ourmsg->data_len);
999 
1000 			if (ourmsg->data_len)
1001 				bcopy(ourmsg->data, neg->service.data,
1002 				    ourmsg->data_len);
1003 			neg->service_len = ourmsg->data_len;
1004 			neg->pkt->pkt_header.ph.code = PADT_CODE;
1005 			/*
1006 			 * Wait for PADI packet coming from Ethernet.
1007 			 */
1008 			sp->state = PPPOE_LISTENING;
1009 			LIST_INSERT_HEAD(&privp->listeners, sp, sessions);
1010 			break;
1011 		case NGM_PPPOE_OFFER:
1012 			/*
1013 			 * Check the hook exists and is Uninitialised.
1014 			 * Store the originator of this message so we can send
1015 			 * a success of fail message to them later.
1016 			 * Store the AC-Name given and go to PRIMED.
1017 			 */
1018 			neg->ac_name.hdr.tag_type = PTT_AC_NAME;
1019 			neg->ac_name.hdr.tag_len =
1020 			    htons((uint16_t)ourmsg->data_len);
1021 			if (ourmsg->data_len)
1022 				bcopy(ourmsg->data, neg->ac_name.data,
1023 				    ourmsg->data_len);
1024 			neg->ac_name_len = ourmsg->data_len;
1025 			neg->pkt->pkt_header.ph.code = PADO_CODE;
1026 			/*
1027 			 * Wait for PADI packet coming from hook.
1028 			 */
1029 			sp->state = PPPOE_PRIMED;
1030 			break;
1031 		case NGM_PPPOE_SERVICE:
1032 			/*
1033 			 * Check the session is primed.
1034 			 * for now just allow ONE service to be advertised.
1035 			 * If you do it twice you just overwrite.
1036 			 */
1037 			if (sp->state != PPPOE_PRIMED) {
1038 				log(LOG_NOTICE, "ng_pppoe[%x]: session not "
1039 				    "primed\n", node->nd_ID);
1040 				LEAVE(EISCONN);
1041 			}
1042 			neg = sp->neg;
1043 			neg->service.hdr.tag_type = PTT_SRV_NAME;
1044 			neg->service.hdr.tag_len =
1045 			    htons((uint16_t)ourmsg->data_len);
1046 
1047 			if (ourmsg->data_len)
1048 				bcopy(ourmsg->data, neg->service.data,
1049 				    ourmsg->data_len);
1050 			neg->service_len = ourmsg->data_len;
1051 			break;
1052 		case NGM_PPPOE_SETMODE:
1053 		    {
1054 			char *s;
1055 			size_t len;
1056 
1057 			if (msg->header.arglen == 0)
1058 				LEAVE(EINVAL);
1059 
1060 			s = (char *)msg->data;
1061 			len = msg->header.arglen - 1;
1062 
1063 			/* Search for matching mode string. */
1064 			if (len == strlen(NG_PPPOE_STANDARD) &&
1065 			    (strncmp(NG_PPPOE_STANDARD, s, len) == 0)) {
1066 				privp->flags = 0;
1067 				privp->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1068 				break;
1069 			}
1070 			if (len == strlen(NG_PPPOE_3COM) &&
1071 			    (strncmp(NG_PPPOE_3COM, s, len) == 0)) {
1072 				privp->flags |= COMPAT_3COM;
1073 				privp->eh.ether_type =
1074 				    ETHERTYPE_PPPOE_3COM_DISC;
1075 				break;
1076 			}
1077 			if (len == strlen(NG_PPPOE_DLINK) &&
1078 			    (strncmp(NG_PPPOE_DLINK, s, len) == 0)) {
1079 				privp->flags |= COMPAT_DLINK;
1080 				break;
1081 			}
1082 			error = EINVAL;
1083 			break;
1084 		    }
1085 		case NGM_PPPOE_GETMODE:
1086 		    {
1087 			char *s;
1088 			size_t len = 0;
1089 
1090 			if (privp->flags == 0)
1091 				len += strlen(NG_PPPOE_STANDARD) + 1;
1092 			if (privp->flags & COMPAT_3COM)
1093 				len += strlen(NG_PPPOE_3COM) + 1;
1094 			if (privp->flags & COMPAT_DLINK)
1095 				len += strlen(NG_PPPOE_DLINK) + 1;
1096 
1097 			NG_MKRESPONSE(resp, msg, len, M_NOWAIT);
1098 			if (resp == NULL)
1099 				LEAVE(ENOMEM);
1100 
1101 			s = (char *)resp->data;
1102 			if (privp->flags == 0) {
1103 				len = strlen(NG_PPPOE_STANDARD);
1104 				strlcpy(s, NG_PPPOE_STANDARD, len + 1);
1105 				break;
1106 			}
1107 			if (privp->flags & COMPAT_3COM) {
1108 				len = strlen(NG_PPPOE_3COM);
1109 				strlcpy(s, NG_PPPOE_3COM, len + 1);
1110 				s += len;
1111 			}
1112 			if (privp->flags & COMPAT_DLINK) {
1113 				if (s != resp->data)
1114 					*s++ = '|';
1115 				len = strlen(NG_PPPOE_DLINK);
1116 				strlcpy(s, NG_PPPOE_DLINK, len + 1);
1117 			}
1118 			break;
1119 		    }
1120 		case NGM_PPPOE_SETENADDR:
1121 			if (msg->header.arglen != ETHER_ADDR_LEN)
1122 				LEAVE(EINVAL);
1123 			bcopy(msg->data, &privp->eh.ether_shost,
1124 			    ETHER_ADDR_LEN);
1125 			break;
1126 		case NGM_PPPOE_SETMAXP:
1127 			if (msg->header.arglen != sizeof(uint16_t))
1128 				LEAVE(EINVAL);
1129 			privp->max_payload.hdr.tag_type = PTT_MAX_PAYL;
1130 			privp->max_payload.hdr.tag_len = htons(sizeof(uint16_t));
1131 			privp->max_payload.data = htons(*((uint16_t *)msg->data));
1132 			break;
1133 		case NGM_PPPOE_SEND_HURL:
1134 		    {
1135 			struct mbuf *m;
1136 
1137 			/* Generate a packet of that type. */
1138 			m = m_gethdr(M_NOWAIT, MT_DATA);
1139 			if (m == NULL)
1140 				log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
1141 				    "mbufs\n", node->nd_ID);
1142 			else {
1143 				struct pppoe_full_hdr *wh;
1144 				struct pppoe_tag *tag;
1145 				int     error = 0;
1146 
1147 				wh = mtod(m, struct pppoe_full_hdr *);
1148 				bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1149 
1150 				/* Revert the stored header to DISC/PADM mode. */
1151 				wh->ph.code = PADM_CODE;
1152 				/*
1153 				 * Configure ethertype depending on what
1154 				 * was used during sessions stage.
1155 				 */
1156 				if (wh->eh.ether_type ==
1157 				    ETHERTYPE_PPPOE_3COM_SESS)
1158 					wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
1159 				else
1160 					wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1161 				/*
1162 				 * Add PADM message and adjust sizes.
1163 				 */
1164 				tag = (void *)(&wh->ph + 1);
1165 				tag->tag_type = PTT_HURL;
1166 				tag->tag_len = htons(ourmsg->data_len);
1167 				strncpy((char *)(tag + 1), ourmsg->data, ourmsg->data_len);
1168 				m->m_pkthdr.len = m->m_len = sizeof(*wh) + sizeof(*tag) +
1169 				    ourmsg->data_len;
1170 				wh->ph.length = htons(sizeof(*tag) + ourmsg->data_len);
1171 				NG_SEND_DATA_ONLY(error,
1172 				    privp->ethernet_hook, m);
1173 			}
1174 			break;
1175 		    }
1176 		case NGM_PPPOE_SEND_MOTM:
1177 		    {
1178 			struct mbuf *m;
1179 
1180 			/* Generate a packet of that type. */
1181 			m = m_gethdr(M_NOWAIT, MT_DATA);
1182 			if (m == NULL)
1183 				log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
1184 				    "mbufs\n", node->nd_ID);
1185 			else {
1186 				struct pppoe_full_hdr *wh;
1187 				struct pppoe_tag *tag;
1188 				int     error = 0;
1189 
1190 				wh = mtod(m, struct pppoe_full_hdr *);
1191 				bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1192 
1193 				/* Revert the stored header to DISC/PADM mode. */
1194 				wh->ph.code = PADM_CODE;
1195 				/*
1196 				 * Configure ethertype depending on what
1197 				 * was used during sessions stage.
1198 				 */
1199 				if (wh->eh.ether_type ==
1200 				    ETHERTYPE_PPPOE_3COM_SESS)
1201 					wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
1202 				else
1203 					wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1204 				/*
1205 				 * Add PADM message and adjust sizes.
1206 				 */
1207 				tag = (void *)(&wh->ph + 1);
1208 				tag->tag_type = PTT_MOTM;
1209 				tag->tag_len = htons(ourmsg->data_len);
1210 				strncpy((char *)(tag + 1), ourmsg->data, ourmsg->data_len);
1211 				m->m_pkthdr.len = m->m_len = sizeof(*wh) + sizeof(*tag) +
1212 				    ourmsg->data_len;
1213 				wh->ph.length = htons(sizeof(*tag) + ourmsg->data_len);
1214 				NG_SEND_DATA_ONLY(error,
1215 				    privp->ethernet_hook, m);
1216 			}
1217 			break;
1218 		    }
1219 		default:
1220 			LEAVE(EINVAL);
1221 		}
1222 		break;
1223 	case NGM_ETHER_COOKIE:
1224 		if (!(msg->header.flags & NGF_RESP))
1225 			LEAVE(EINVAL);
1226 		switch (msg->header.cmd) {
1227 		case NGM_ETHER_GET_ENADDR:
1228 			if (msg->header.arglen != ETHER_ADDR_LEN)
1229 				LEAVE(EINVAL);
1230 			bcopy(msg->data, &privp->eh.ether_shost,
1231 			    ETHER_ADDR_LEN);
1232 			break;
1233 		default:
1234 			LEAVE(EINVAL);
1235 		}
1236 		break;
1237 	default:
1238 		LEAVE(EINVAL);
1239 	}
1240 
1241 	/* Take care of synchronous response, if any. */
1242 quit:
1243 	CTR2(KTR_NET, "%20s: returning %d", __func__, error);
1244 	NG_RESPOND_MSG(error, node, item, resp);
1245 	/* Free the message and return. */
1246 	NG_FREE_MSG(msg);
1247 	return(error);
1248 }
1249 
1250 /*
1251  * Start a client into the first state. A separate function because
1252  * it can be needed if the negotiation times out.
1253  */
1254 static void
1255 pppoe_start(sessp sp)
1256 {
1257 	hook_p	hook = sp->hook;
1258 	node_p	node = NG_HOOK_NODE(hook);
1259 	priv_p	privp = NG_NODE_PRIVATE(node);
1260 	negp	neg = sp->neg;
1261 	struct  mbuf *m0;
1262 	int	error;
1263 
1264 	/*
1265 	 * Kick the state machine into starting up.
1266 	 */
1267 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1268 	sp->state = PPPOE_SINIT;
1269 	/*
1270 	 * Reset the packet header to broadcast. Since we are
1271 	 * in a client mode use configured ethertype.
1272 	 */
1273 	memcpy((void *)&neg->pkt->pkt_header.eh, &privp->eh,
1274 	    sizeof(struct ether_header));
1275 	neg->pkt->pkt_header.ph.code = PADI_CODE;
1276 	init_tags(sp);
1277 	insert_tag(sp, &neg->host_uniq.hdr);
1278 	insert_tag(sp, &neg->service.hdr);
1279 	if (privp->max_payload.data != 0)
1280 		insert_tag(sp, &privp->max_payload.hdr);
1281 	make_packet(sp);
1282 	/*
1283 	 * Send packet and prepare to retransmit it after timeout.
1284 	 */
1285 	ng_callout(&neg->handle, node, hook, PPPOE_INITIAL_TIMEOUT * hz,
1286 	    pppoe_ticker, NULL, 0);
1287 	neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1288 	m0 = m_copypacket(neg->m, M_NOWAIT);
1289 	NG_SEND_DATA_ONLY(error, privp->ethernet_hook, m0);
1290 }
1291 
1292 static int
1293 send_acname(sessp sp, const struct pppoe_tag *tag)
1294 {
1295 	int error, tlen;
1296 	struct ng_mesg *msg;
1297 	struct ngpppoe_sts *sts;
1298 
1299 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1300 
1301 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_ACNAME,
1302 	    sizeof(struct ngpppoe_sts), M_NOWAIT);
1303 	if (msg == NULL)
1304 		return (ENOMEM);
1305 
1306 	sts = (struct ngpppoe_sts *)msg->data;
1307 	tlen = min(NG_HOOKSIZ - 1, ntohs(tag->tag_len));
1308 	strncpy(sts->hook, (const char *)(tag + 1), tlen);
1309 	sts->hook[tlen] = '\0';
1310 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1311 
1312 	return (error);
1313 }
1314 
1315 static int
1316 send_sessionid(sessp sp)
1317 {
1318 	int error;
1319 	struct ng_mesg *msg;
1320 
1321 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1322 
1323 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SESSIONID,
1324 	    sizeof(uint16_t), M_NOWAIT);
1325 	if (msg == NULL)
1326 		return (ENOMEM);
1327 
1328 	*(uint16_t *)msg->data = sp->Session_ID;
1329 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1330 
1331 	return (error);
1332 }
1333 
1334 static int
1335 send_maxp(sessp sp, const struct pppoe_tag *tag)
1336 {
1337 	int error;
1338 	struct ng_mesg *msg;
1339 	struct ngpppoe_maxp *maxp;
1340 
1341 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1342 
1343 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SETMAXP,
1344 	    sizeof(struct ngpppoe_maxp), M_NOWAIT);
1345 	if (msg == NULL)
1346 		return (ENOMEM);
1347 
1348 	maxp = (struct ngpppoe_maxp *)msg->data;
1349 	strncpy(maxp->hook, NG_HOOK_NAME(sp->hook), NG_HOOKSIZ);
1350 	maxp->data = ntohs(((const struct maxptag *)tag)->data);
1351 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1352 
1353 	return (error);
1354 }
1355 
1356 static int
1357 send_hurl(sessp sp, const struct pppoe_tag *tag)
1358 {
1359 	int error, tlen;
1360 	struct ng_mesg *msg;
1361 	struct ngpppoe_padm *padm;
1362 
1363 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1364 
1365 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_HURL,
1366 	    sizeof(struct ngpppoe_padm), M_NOWAIT);
1367 	if (msg == NULL)
1368 		return (ENOMEM);
1369 
1370 	padm = (struct ngpppoe_padm *)msg->data;
1371 	tlen = min(PPPOE_PADM_VALUE_SIZE - 1, ntohs(tag->tag_len));
1372 	strncpy(padm->msg, (const char *)(tag + 1), tlen);
1373 	padm->msg[tlen] = '\0';
1374 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1375 
1376 	return (error);
1377 }
1378 
1379 static int
1380 send_motm(sessp sp, const struct pppoe_tag *tag)
1381 {
1382 	int error, tlen;
1383 	struct ng_mesg *msg;
1384 	struct ngpppoe_padm *padm;
1385 
1386 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1387 
1388 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_MOTM,
1389 	    sizeof(struct ngpppoe_padm), M_NOWAIT);
1390 	if (msg == NULL)
1391 		return (ENOMEM);
1392 
1393 	padm = (struct ngpppoe_padm *)msg->data;
1394 	tlen = min(PPPOE_PADM_VALUE_SIZE - 1, ntohs(tag->tag_len));
1395 	strncpy(padm->msg, (const char *)(tag + 1), tlen);
1396 	padm->msg[tlen] = '\0';
1397 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1398 
1399 	return (error);
1400 }
1401 
1402 /*
1403  * Receive data from session hook and do something with it.
1404  */
1405 static int
1406 ng_pppoe_rcvdata(hook_p hook, item_p item)
1407 {
1408 	node_p			node = NG_HOOK_NODE(hook);
1409 	const priv_p		privp = NG_NODE_PRIVATE(node);
1410 	sessp			sp = NG_HOOK_PRIVATE(hook);
1411 	struct pppoe_full_hdr	*wh;
1412 	struct mbuf		*m;
1413 	int			error;
1414 
1415 	CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1416 	    __func__, node->nd_ID, node, item, hook->hk_name, hook);
1417 
1418 	NGI_GET_M(item, m);
1419 	switch (sp->state) {
1420 	case	PPPOE_NEWCONNECTED:
1421 	case	PPPOE_CONNECTED: {
1422 		/*
1423 		 * Remove PPP address and control fields, if any.
1424 		 * For example, ng_ppp(4) always sends LCP packets
1425 		 * with address and control fields as required by
1426 		 * generic PPP. PPPoE is an exception to the rule.
1427 		 */
1428 		if (m->m_pkthdr.len >= 2) {
1429 			if (m->m_len < 2 && !(m = m_pullup(m, 2)))
1430 				LEAVE(ENOBUFS);
1431 			if (mtod(m, u_char *)[0] == 0xff &&
1432 			    mtod(m, u_char *)[1] == 0x03)
1433 				m_adj(m, 2);
1434 		}
1435 		/*
1436 		 * Bang in a pre-made header, and set the length up
1437 		 * to be correct. Then send it to the ethernet driver.
1438 		 */
1439 		M_PREPEND(m, sizeof(*wh), M_NOWAIT);
1440 		if (m == NULL)
1441 			LEAVE(ENOBUFS);
1442 
1443 		wh = mtod(m, struct pppoe_full_hdr *);
1444 		bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1445 		wh->ph.length = htons(m->m_pkthdr.len - sizeof(*wh));
1446 		NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m);
1447 		privp->packets_out++;
1448 		break;
1449 		}
1450 	case	PPPOE_PRIMED: {
1451 		struct {
1452 			struct pppoe_tag hdr;
1453 			union	uniq	data;
1454 		} __packed 	uniqtag;
1455 		const struct pppoe_tag	*tag;
1456 		struct mbuf 	*m0;
1457 		const struct pppoe_hdr	*ph;
1458 		negp		neg = sp->neg;
1459 	        uint16_t	session;
1460 		uint16_t	length;
1461 		uint8_t		code;
1462 
1463 		/*
1464 		 * A PADI packet is being returned by the application
1465 		 * that has set up this hook. This indicates that it
1466 		 * wants us to offer service.
1467 		 */
1468 		if (m->m_len < sizeof(*wh)) {
1469 			m = m_pullup(m, sizeof(*wh));
1470 			if (m == NULL)
1471 				LEAVE(ENOBUFS);
1472 		}
1473 		wh = mtod(m, struct pppoe_full_hdr *);
1474 		ph = &wh->ph;
1475 		session = ntohs(wh->ph.sid);
1476 		length = ntohs(wh->ph.length);
1477 		code = wh->ph.code;
1478 		/* Use peers mode in session. */
1479 		neg->pkt->pkt_header.eh.ether_type = wh->eh.ether_type;
1480 		if (code != PADI_CODE)
1481 			LEAVE(EINVAL);
1482 		ng_uncallout(&neg->handle, node);
1483 
1484 		/*
1485 		 * This is the first time we hear
1486 		 * from the client, so note it's
1487 		 * unicast address, replacing the
1488 		 * broadcast address.
1489 		 */
1490 		bcopy(wh->eh.ether_shost,
1491 			neg->pkt->pkt_header.eh.ether_dhost,
1492 			ETHER_ADDR_LEN);
1493 		sp->state = PPPOE_SOFFER;
1494 		neg->timeout = 0;
1495 		neg->pkt->pkt_header.ph.code = PADO_CODE;
1496 
1497 		/*
1498 		 * Start working out the tags to respond with.
1499 		 */
1500 		uniqtag.hdr.tag_type = PTT_AC_COOKIE;
1501 		uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(sp));
1502 		uniqtag.data.pointer = sp;
1503 		init_tags(sp);
1504 		insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1505 		if ((tag = get_tag(ph, PTT_SRV_NAME)))
1506 			insert_tag(sp, tag);	  /* return service */
1507 		/*
1508 		 * If we have a NULL service request
1509 		 * and have an extra service defined in this hook,
1510 		 * then also add a tag for the extra service.
1511 		 * XXX this is a hack. eventually we should be able
1512 		 * to support advertising many services, not just one
1513 		 */
1514 		if (((tag == NULL) || (tag->tag_len == 0)) &&
1515 		    (neg->service.hdr.tag_len != 0)) {
1516 			insert_tag(sp, &neg->service.hdr); /* SERVICE */
1517 		}
1518 		if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1519 			insert_tag(sp, tag); /* returned hostunique */
1520 		insert_tag(sp, &uniqtag.hdr);
1521 		scan_tags(sp, ph);
1522 		make_packet(sp);
1523 		/*
1524 		 * Send the offer but if they don't respond
1525 		 * in PPPOE_OFFER_TIMEOUT seconds, forget about it.
1526 		 */
1527 		ng_callout(&neg->handle, node, hook, PPPOE_OFFER_TIMEOUT * hz,
1528 		    pppoe_ticker, NULL, 0);
1529 		m0 = m_copypacket(sp->neg->m, M_NOWAIT);
1530 		NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1531 		privp->packets_out++;
1532 		break;
1533 		}
1534 
1535 	/*
1536 	 * Packets coming from the hook make no sense
1537 	 * to sessions in the rest of states. Throw them away.
1538 	 */
1539 	default:
1540 		LEAVE(ENETUNREACH);
1541 	}
1542 quit:
1543 	if (item)
1544 		NG_FREE_ITEM(item);
1545 	NG_FREE_M(m);
1546 	return (error);
1547 }
1548 
1549 /*
1550  * Receive data from ether and do something with it.
1551  */
1552 static int
1553 ng_pppoe_rcvdata_ether(hook_p hook, item_p item)
1554 {
1555 	node_p			node = NG_HOOK_NODE(hook);
1556 	const priv_p		privp = NG_NODE_PRIVATE(node);
1557 	sessp			sp;
1558 	const struct pppoe_tag	*utag = NULL, *tag = NULL;
1559 	const struct pppoe_tag	sntag = { PTT_SRV_NAME, 0 };
1560 	const struct pppoe_full_hdr *wh;
1561 	const struct pppoe_hdr	*ph;
1562 	negp			neg = NULL;
1563 	struct mbuf		*m;
1564 	hook_p 			sendhook;
1565 	int			error = 0;
1566 	uint16_t		session;
1567 	uint16_t		length;
1568 	uint8_t			code;
1569 	struct	mbuf 		*m0;
1570 
1571 	CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1572 	    __func__, node->nd_ID, node, item, hook->hk_name, hook);
1573 
1574 	NGI_GET_M(item, m);
1575 	/*
1576 	 * Dig out various fields from the packet.
1577 	 * Use them to decide where to send it.
1578 	 */
1579 	privp->packets_in++;
1580 	if( m->m_len < sizeof(*wh)) {
1581 		m = m_pullup(m, sizeof(*wh)); /* Checks length */
1582 		if (m == NULL) {
1583 			log(LOG_NOTICE, "ng_pppoe[%x]: couldn't "
1584 			    "m_pullup(wh)\n", node->nd_ID);
1585 			LEAVE(ENOBUFS);
1586 		}
1587 	}
1588 	wh = mtod(m, struct pppoe_full_hdr *);
1589 	length = ntohs(wh->ph.length);
1590 	switch(wh->eh.ether_type) {
1591 	case	ETHERTYPE_PPPOE_3COM_DISC: /* fall through */
1592 	case	ETHERTYPE_PPPOE_DISC:
1593 		/*
1594 		 * We need to try to make sure that the tag area
1595 		 * is contiguous, or we could wander off the end
1596 		 * of a buffer and make a mess.
1597 		 * (Linux wouldn't have this problem).
1598 		 */
1599 		if (m->m_pkthdr.len <= MHLEN) {
1600 			if( m->m_len < m->m_pkthdr.len) {
1601 				m = m_pullup(m, m->m_pkthdr.len);
1602 				if (m == NULL) {
1603 					log(LOG_NOTICE, "ng_pppoe[%x]: "
1604 					    "couldn't m_pullup(pkthdr)\n",
1605 					    node->nd_ID);
1606 					LEAVE(ENOBUFS);
1607 				}
1608 			}
1609 		}
1610 		if (m->m_len != m->m_pkthdr.len) {
1611 			/*
1612 			 * It's not all in one piece.
1613 			 * We need to do extra work.
1614 			 * Put it into a cluster.
1615 			 */
1616 			struct mbuf *n;
1617 			n = m_dup(m, M_NOWAIT);
1618 			m_freem(m);
1619 			m = n;
1620 			if (m) {
1621 				/* just check we got a cluster */
1622 				if (m->m_len != m->m_pkthdr.len) {
1623 					m_freem(m);
1624 					m = NULL;
1625 				}
1626 			}
1627 			if (m == NULL) {
1628 				log(LOG_NOTICE, "ng_pppoe[%x]: packet "
1629 				    "fragmented\n", node->nd_ID);
1630 				LEAVE(EMSGSIZE);
1631 			}
1632 		}
1633 		wh = mtod(m, struct pppoe_full_hdr *);
1634 		length = ntohs(wh->ph.length);
1635 		ph = &wh->ph;
1636 		session = ntohs(wh->ph.sid);
1637 		code = wh->ph.code;
1638 
1639 		switch(code) {
1640 		case	PADI_CODE:
1641 			/*
1642 			 * We are a server:
1643 			 * Look for a hook with the required service and send
1644 			 * the ENTIRE packet up there. It should come back to
1645 			 * a new hook in PRIMED state. Look there for further
1646 			 * processing.
1647 			 */
1648 			tag = get_tag(ph, PTT_SRV_NAME);
1649 			if (tag == NULL)
1650 				tag = &sntag;
1651 
1652 			/*
1653 			 * First, try to match Service-Name against our
1654 			 * listening hooks. If no success and we are in D-Link
1655 			 * compat mode and Service-Name is empty, then we
1656 			 * broadcast the PADI to all listening hooks.
1657 			 */
1658 			sendhook = pppoe_match_svc(node, tag);
1659 			if (sendhook != NULL)
1660 				NG_FWD_NEW_DATA(error, item, sendhook, m);
1661 			else if (privp->flags & COMPAT_DLINK &&
1662 				 ntohs(tag->tag_len) == 0)
1663 				error = pppoe_broadcast_padi(node, m);
1664 			else
1665 				error = ENETUNREACH;
1666 			break;
1667 		case	PADO_CODE:
1668 			/*
1669 			 * We are a client:
1670 			 * Use the host_uniq tag to find the hook this is in
1671 			 * response to. Received #2, now send #3
1672 			 * For now simply accept the first we receive.
1673 			 */
1674 			utag = get_tag(ph, PTT_HOST_UNIQ);
1675 			if (utag == NULL) {
1676 				log(LOG_NOTICE, "ng_pppoe[%x]: no host "
1677 				    "unique field\n", node->nd_ID);
1678 				LEAVE(ENETUNREACH);
1679 			}
1680 
1681 			sendhook = pppoe_finduniq(node, utag);
1682 			if (sendhook == NULL) {
1683 				log(LOG_NOTICE, "ng_pppoe[%x]: no "
1684 				    "matching session\n", node->nd_ID);
1685 				LEAVE(ENETUNREACH);
1686 			}
1687 
1688 			/*
1689 			 * Check the session is in the right state.
1690 			 * It needs to be in PPPOE_SINIT.
1691 			 */
1692 			sp = NG_HOOK_PRIVATE(sendhook);
1693 			if (sp->state == PPPOE_SREQ ||
1694 			    sp->state == PPPOE_CONNECTED) {
1695 				break;	/* Multiple PADO is OK. */
1696 			}
1697 			if (sp->state != PPPOE_SINIT) {
1698 				log(LOG_NOTICE, "ng_pppoe[%x]: session "
1699 				    "in wrong state\n", node->nd_ID);
1700 				LEAVE(ENETUNREACH);
1701 			}
1702 			neg = sp->neg;
1703 			/* If requested specific AC-name, check it. */
1704 			if (neg->ac_name_len) {
1705 				tag = get_tag(ph, PTT_AC_NAME);
1706 				if (!tag) {
1707 					/* No PTT_AC_NAME in PADO */
1708 					break;
1709 				}
1710 				if (neg->ac_name_len != htons(tag->tag_len) ||
1711 				    strncmp(neg->ac_name.data,
1712 				    (const char *)(tag + 1),
1713 				    neg->ac_name_len) != 0) {
1714 					break;
1715 				}
1716 			}
1717 			sp->state = PPPOE_SREQ;
1718 			ng_uncallout(&neg->handle, node);
1719 
1720 			/*
1721 			 * This is the first time we hear
1722 			 * from the server, so note it's
1723 			 * unicast address, replacing the
1724 			 * broadcast address .
1725 			 */
1726 			bcopy(wh->eh.ether_shost,
1727 				neg->pkt->pkt_header.eh.ether_dhost,
1728 				ETHER_ADDR_LEN);
1729 			neg->timeout = 0;
1730 			neg->pkt->pkt_header.ph.code = PADR_CODE;
1731 			init_tags(sp);
1732 			insert_tag(sp, utag);      	/* Host Unique */
1733 			if ((tag = get_tag(ph, PTT_AC_COOKIE)))
1734 				insert_tag(sp, tag); 	/* return cookie */
1735 			if ((tag = get_tag(ph, PTT_AC_NAME))) {
1736 				insert_tag(sp, tag); 	/* return it */
1737 				send_acname(sp, tag);
1738 			}
1739 			if ((tag = get_tag(ph, PTT_MAX_PAYL)) &&
1740 			    (privp->max_payload.data != 0))
1741 				insert_tag(sp, tag);	/* return it */
1742 			insert_tag(sp, &neg->service.hdr); /* Service */
1743 			scan_tags(sp, ph);
1744 			make_packet(sp);
1745 			sp->state = PPPOE_SREQ;
1746 			ng_callout(&neg->handle, node, sp->hook,
1747 			    PPPOE_INITIAL_TIMEOUT * hz,
1748 			    pppoe_ticker, NULL, 0);
1749 			neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1750 			m0 = m_copypacket(neg->m, M_NOWAIT);
1751 			NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1752 			break;
1753 		case	PADR_CODE:
1754 			/*
1755 			 * We are a server:
1756 			 * Use the ac_cookie tag to find the
1757 			 * hook this is in response to.
1758 			 */
1759 			utag = get_tag(ph, PTT_AC_COOKIE);
1760 			if ((utag == NULL) ||
1761 			    (ntohs(utag->tag_len) != sizeof(sp))) {
1762 				LEAVE(ENETUNREACH);
1763 			}
1764 
1765 			sendhook = pppoe_findcookie(node, utag);
1766 			if (sendhook == NULL)
1767 				LEAVE(ENETUNREACH);
1768 
1769 			/*
1770 			 * Check the session is in the right state.
1771 			 * It needs to be in PPPOE_SOFFER or PPPOE_NEWCONNECTED.
1772 			 * If the latter, then this is a retry by the client,
1773 			 * so be nice, and resend.
1774 			 */
1775 			sp = NG_HOOK_PRIVATE(sendhook);
1776 			if (sp->state == PPPOE_NEWCONNECTED) {
1777 				/*
1778 				 * Whoa! drop back to resend that PADS packet.
1779 				 * We should still have a copy of it.
1780 				 */
1781 				sp->state = PPPOE_SOFFER;
1782 			} else if (sp->state != PPPOE_SOFFER)
1783 				LEAVE (ENETUNREACH);
1784 			neg = sp->neg;
1785 			ng_uncallout(&neg->handle, node);
1786 			neg->pkt->pkt_header.ph.code = PADS_CODE;
1787 			if (sp->Session_ID == 0) {
1788 				neg->pkt->pkt_header.ph.sid =
1789 				    htons(pppoe_getnewsession(sp));
1790 			}
1791 			send_sessionid(sp);
1792 			neg->timeout = 0;
1793 			/*
1794 			 * start working out the tags to respond with.
1795 			 */
1796 			init_tags(sp);
1797 			insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1798 			if ((tag = get_tag(ph, PTT_SRV_NAME)))
1799 				insert_tag(sp, tag);/* return service */
1800 			if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1801 				insert_tag(sp, tag); /* return it */
1802 			insert_tag(sp, utag);	/* ac_cookie */
1803 			scan_tags(sp, ph);
1804 			make_packet(sp);
1805 			sp->state = PPPOE_NEWCONNECTED;
1806 
1807 			/* Send the PADS without a timeout - we're now connected. */
1808 			m0 = m_copypacket(sp->neg->m, M_NOWAIT);
1809 			NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1810 
1811 			/*
1812 			 * Having sent the last Negotiation header,
1813 			 * Set up the stored packet header to be correct for
1814 			 * the actual session. But keep the negotialtion stuff
1815 			 * around in case we need to resend this last packet.
1816 			 * We'll discard it when we move from NEWCONNECTED
1817 			 * to CONNECTED
1818 			 */
1819 			sp->pkt_hdr = neg->pkt->pkt_header;
1820 			/* Configure ethertype depending on what
1821 			 * ethertype was used at discovery phase */
1822 			if (sp->pkt_hdr.eh.ether_type ==
1823 			    ETHERTYPE_PPPOE_3COM_DISC)
1824 				sp->pkt_hdr.eh.ether_type
1825 					= ETHERTYPE_PPPOE_3COM_SESS;
1826 			else
1827 				sp->pkt_hdr.eh.ether_type
1828 					= ETHERTYPE_PPPOE_SESS;
1829 			sp->pkt_hdr.ph.code = 0;
1830 			pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1831 			break;
1832 		case	PADS_CODE:
1833 			/*
1834 			 * We are a client:
1835 			 * Use the host_uniq tag to find the hook this is in
1836 			 * response to. Take the session ID and store it away.
1837 			 * Also make sure the pre-made header is correct and
1838 			 * set us into Session mode.
1839 			 */
1840 			utag = get_tag(ph, PTT_HOST_UNIQ);
1841 			if (utag == NULL) {
1842 				LEAVE (ENETUNREACH);
1843 			}
1844 			sendhook = pppoe_finduniq(node, utag);
1845 			if (sendhook == NULL)
1846 				LEAVE(ENETUNREACH);
1847 
1848 			/*
1849 			 * Check the session is in the right state.
1850 			 * It needs to be in PPPOE_SREQ.
1851 			 */
1852 			sp = NG_HOOK_PRIVATE(sendhook);
1853 			if (sp->state != PPPOE_SREQ)
1854 				LEAVE(ENETUNREACH);
1855 			neg = sp->neg;
1856 			ng_uncallout(&neg->handle, node);
1857 			neg->pkt->pkt_header.ph.sid = wh->ph.sid;
1858 			sp->Session_ID = ntohs(wh->ph.sid);
1859 			pppoe_addsession(sp);
1860 			send_sessionid(sp);
1861 			neg->timeout = 0;
1862 			sp->state = PPPOE_CONNECTED;
1863 			/*
1864 			 * Now we have gone to Connected mode,
1865 			 * Free all resources needed for negotiation.
1866 			 * Keep a copy of the header we will be using.
1867 			 */
1868 			sp->pkt_hdr = neg->pkt->pkt_header;
1869 			if (privp->flags & COMPAT_3COM)
1870 				sp->pkt_hdr.eh.ether_type
1871 					= ETHERTYPE_PPPOE_3COM_SESS;
1872 			else
1873 				sp->pkt_hdr.eh.ether_type
1874 					= ETHERTYPE_PPPOE_SESS;
1875 			sp->pkt_hdr.ph.code = 0;
1876 			m_freem(neg->m);
1877 			free(sp->neg, M_NETGRAPH_PPPOE);
1878 			sp->neg = NULL;
1879 			if ((tag = get_tag(ph, PTT_MAX_PAYL)) &&
1880 			    (privp->max_payload.data != 0))
1881 				send_maxp(sp, tag);
1882 			pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1883 			break;
1884 		case	PADT_CODE:
1885 			/*
1886 			 * Find matching peer/session combination.
1887 			 */
1888 			sp = pppoe_findsession(privp, wh);
1889 			if (sp == NULL)
1890 				LEAVE(ENETUNREACH);
1891 			/* Disconnect that hook. */
1892 			ng_rmhook_self(sp->hook);
1893 			break;
1894 		case	PADM_CODE:
1895 			/*
1896 			 * We are a client:
1897 			 * find matching peer/session combination.
1898 			 */
1899 			sp = pppoe_findsession(privp, wh);
1900 			if (sp == NULL)
1901 				LEAVE (ENETUNREACH);
1902 			if ((tag = get_tag(ph, PTT_HURL)))
1903 				send_hurl(sp, tag);
1904 			if ((tag = get_tag(ph, PTT_MOTM)))
1905 				send_motm(sp, tag);
1906 			break;
1907 		default:
1908 			LEAVE(EPFNOSUPPORT);
1909 		}
1910 		break;
1911 	case	ETHERTYPE_PPPOE_3COM_SESS:
1912 	case	ETHERTYPE_PPPOE_SESS:
1913 		/*
1914 		 * Find matching peer/session combination.
1915 		 */
1916 		sp = pppoe_findsession(privp, wh);
1917 		if (sp == NULL)
1918 			LEAVE (ENETUNREACH);
1919 		m_adj(m, sizeof(*wh));
1920 
1921 		/* If packet too short, dump it. */
1922 		if (m->m_pkthdr.len < length)
1923 			LEAVE(EMSGSIZE);
1924 		/* Also need to trim excess at the end */
1925 		if (m->m_pkthdr.len > length) {
1926 			m_adj(m, -((int)(m->m_pkthdr.len - length)));
1927 		}
1928 		if ( sp->state != PPPOE_CONNECTED) {
1929 			if (sp->state == PPPOE_NEWCONNECTED) {
1930 				sp->state = PPPOE_CONNECTED;
1931 				/*
1932 				 * Now we have gone to Connected mode,
1933 				 * Free all resources needed for negotiation.
1934 				 * Be paranoid about whether there may be
1935 				 * a timeout.
1936 				 */
1937 				m_freem(sp->neg->m);
1938 				ng_uncallout(&sp->neg->handle, node);
1939 				free(sp->neg, M_NETGRAPH_PPPOE);
1940 				sp->neg = NULL;
1941 			} else {
1942 				LEAVE (ENETUNREACH);
1943 			}
1944 		}
1945 		NG_FWD_NEW_DATA(error, item, sp->hook, m);
1946 		break;
1947 	default:
1948 		LEAVE(EPFNOSUPPORT);
1949 	}
1950 quit:
1951 	if (item)
1952 		NG_FREE_ITEM(item);
1953 	NG_FREE_M(m);
1954 	return (error);
1955 }
1956 
1957 /*
1958  * Receive data from debug hook and bypass it to ether.
1959  */
1960 static int
1961 ng_pppoe_rcvdata_debug(hook_p hook, item_p item)
1962 {
1963 	node_p		node = NG_HOOK_NODE(hook);
1964 	const priv_p	privp = NG_NODE_PRIVATE(node);
1965 	int		error;
1966 
1967 	CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1968 	    __func__, node->nd_ID, node, item, hook->hk_name, hook);
1969 
1970 	NG_FWD_ITEM_HOOK(error, item, privp->ethernet_hook);
1971 	privp->packets_out++;
1972 	return (error);
1973 }
1974 
1975 /*
1976  * Do local shutdown processing..
1977  * If we are a persistent device, we might refuse to go away, and
1978  * we'd only remove our links and reset ourself.
1979  */
1980 static int
1981 ng_pppoe_shutdown(node_p node)
1982 {
1983 	const priv_p privp = NG_NODE_PRIVATE(node);
1984 	int	i;
1985 
1986 	for (i = 0; i < SESSHASHSIZE; i++)
1987 	    mtx_destroy(&privp->sesshash[i].mtx);
1988 	NG_NODE_SET_PRIVATE(node, NULL);
1989 	NG_NODE_UNREF(privp->node);
1990 	free(privp, M_NETGRAPH_PPPOE);
1991 	return (0);
1992 }
1993 
1994 /*
1995  * Hook disconnection
1996  *
1997  * Clean up all dangling links and information about the session/hook.
1998  * For this type, removal of the last link destroys the node.
1999  */
2000 static int
2001 ng_pppoe_disconnect(hook_p hook)
2002 {
2003 	node_p node = NG_HOOK_NODE(hook);
2004 	priv_p privp = NG_NODE_PRIVATE(node);
2005 	sessp	sp;
2006 
2007 	if (hook == privp->debug_hook) {
2008 		privp->debug_hook = NULL;
2009 	} else if (hook == privp->ethernet_hook) {
2010 		privp->ethernet_hook = NULL;
2011 		if (NG_NODE_IS_VALID(node))
2012 			ng_rmnode_self(node);
2013 	} else {
2014 		sp = NG_HOOK_PRIVATE(hook);
2015 		if (sp->state != PPPOE_SNONE ) {
2016 			pppoe_send_event(sp, NGM_PPPOE_CLOSE);
2017 		}
2018 		/*
2019 		 * According to the spec, if we are connected,
2020 		 * we should send a DISC packet if we are shutting down
2021 		 * a session.
2022 		 */
2023 		if ((privp->ethernet_hook)
2024 		&& ((sp->state == PPPOE_CONNECTED)
2025 		 || (sp->state == PPPOE_NEWCONNECTED))) {
2026 			struct mbuf *m;
2027 
2028 			/* Generate a packet of that type. */
2029 			m = m_gethdr(M_NOWAIT, MT_DATA);
2030 			if (m == NULL)
2031 				log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
2032 				    "mbufs\n", node->nd_ID);
2033 			else {
2034 				struct pppoe_full_hdr *wh;
2035 				struct pppoe_tag *tag;
2036 				int	msglen = strlen(SIGNOFF);
2037 				int	error = 0;
2038 
2039 				wh = mtod(m, struct pppoe_full_hdr *);
2040 				bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
2041 
2042 				/* Revert the stored header to DISC/PADT mode. */
2043 				wh->ph.code = PADT_CODE;
2044 				/*
2045 				 * Configure ethertype depending on what
2046 				 * was used during sessions stage.
2047 				 */
2048 				if (wh->eh.ether_type ==
2049 				    ETHERTYPE_PPPOE_3COM_SESS)
2050 					wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
2051 				else
2052 					wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
2053 				/*
2054 				 * Add a General error message and adjust
2055 				 * sizes.
2056 				 */
2057 				tag = (void *)(&wh->ph + 1);
2058 				tag->tag_type = PTT_GEN_ERR;
2059 				tag->tag_len = htons((u_int16_t)msglen);
2060 				strncpy((char *)(tag + 1), SIGNOFF, msglen);
2061 				m->m_pkthdr.len = m->m_len = sizeof(*wh) + sizeof(*tag) +
2062 				    msglen;
2063 				wh->ph.length = htons(sizeof(*tag) + msglen);
2064 				NG_SEND_DATA_ONLY(error,
2065 					privp->ethernet_hook, m);
2066 			}
2067 		}
2068 		if (sp->state == PPPOE_LISTENING)
2069 			LIST_REMOVE(sp, sessions);
2070 		else if (sp->Session_ID)
2071 			pppoe_delsession(sp);
2072 		/*
2073 		 * As long as we have somewhere to store the timeout handle,
2074 		 * we may have a timeout pending.. get rid of it.
2075 		 */
2076 		if (sp->neg) {
2077 			ng_uncallout(&sp->neg->handle, node);
2078 			if (sp->neg->m)
2079 				m_freem(sp->neg->m);
2080 			free(sp->neg, M_NETGRAPH_PPPOE);
2081 		}
2082 		free(sp, M_NETGRAPH_PPPOE);
2083 		NG_HOOK_SET_PRIVATE(hook, NULL);
2084 	}
2085 	if ((NG_NODE_NUMHOOKS(node) == 0) &&
2086 	    (NG_NODE_IS_VALID(node)))
2087 		ng_rmnode_self(node);
2088 	return (0);
2089 }
2090 
2091 /*
2092  * Timeouts come here.
2093  */
2094 static void
2095 pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2)
2096 {
2097 	priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
2098 	sessp	sp = NG_HOOK_PRIVATE(hook);
2099 	negp	neg = sp->neg;
2100 	struct mbuf *m0 = NULL;
2101 	int	error = 0;
2102 
2103 	CTR6(KTR_NET, "%20s: node [%x] (%p) hook \"%s\" (%p) session %d",
2104 	    __func__, node->nd_ID, node, hook->hk_name, hook, sp->Session_ID);
2105 	switch(sp->state) {
2106 		/*
2107 		 * Resend the last packet, using an exponential backoff.
2108 		 * After a period of time, stop growing the backoff,
2109 		 * And either leave it, or revert to the start.
2110 		 */
2111 	case	PPPOE_SINIT:
2112 	case	PPPOE_SREQ:
2113 		/* Timeouts on these produce resends. */
2114 		m0 = m_copypacket(sp->neg->m, M_NOWAIT);
2115 		NG_SEND_DATA_ONLY( error, privp->ethernet_hook, m0);
2116 		ng_callout(&neg->handle, node, hook, neg->timeout * hz,
2117 		    pppoe_ticker, NULL, 0);
2118 		if ((neg->timeout <<= 1) > PPPOE_TIMEOUT_LIMIT) {
2119 			if (sp->state == PPPOE_SREQ) {
2120 				/* Revert to SINIT mode. */
2121 				pppoe_start(sp);
2122 			} else {
2123 				neg->timeout = PPPOE_TIMEOUT_LIMIT;
2124 			}
2125 		}
2126 		break;
2127 	case	PPPOE_PRIMED:
2128 	case	PPPOE_SOFFER:
2129 		/* A timeout on these says "give up" */
2130 		ng_rmhook_self(hook);
2131 		break;
2132 	default:
2133 		/* Timeouts have no meaning in other states. */
2134 		log(LOG_NOTICE, "ng_pppoe[%x]: unexpected timeout\n",
2135 		    node->nd_ID);
2136 	}
2137 }
2138 
2139 /*
2140  * Parse an incoming packet to see if any tags should be copied to the
2141  * output packet. Don't do any tags that have been handled in the main
2142  * state machine.
2143  */
2144 static const struct pppoe_tag*
2145 scan_tags(sessp	sp, const struct pppoe_hdr* ph)
2146 {
2147 	const char *const end = (const char *)next_tag(ph);
2148 	const char *ptn;
2149 	const struct pppoe_tag *pt = (const void *)(ph + 1);
2150 
2151 	/*
2152 	 * Keep processing tags while a tag header will still fit.
2153 	 */
2154 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
2155 
2156 	while((const char*)(pt + 1) <= end) {
2157 		/*
2158 		 * If the tag data would go past the end of the packet, abort.
2159 		 */
2160 		ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
2161 		if(ptn > end)
2162 			return NULL;
2163 
2164 		switch (pt->tag_type) {
2165 		case	PTT_RELAY_SID:
2166 			insert_tag(sp, pt);
2167 			break;
2168 		case	PTT_EOL:
2169 			return NULL;
2170 		case	PTT_SRV_NAME:
2171 		case	PTT_AC_NAME:
2172 		case	PTT_HOST_UNIQ:
2173 		case	PTT_AC_COOKIE:
2174 		case	PTT_VENDOR:
2175 		case	PTT_SRV_ERR:
2176 		case	PTT_SYS_ERR:
2177 		case	PTT_GEN_ERR:
2178 		case	PTT_MAX_PAYL:
2179 		case	PTT_HURL:
2180 		case	PTT_MOTM:
2181 			break;
2182 		}
2183 		pt = (const struct pppoe_tag*)ptn;
2184 	}
2185 	return NULL;
2186 }
2187 
2188 static	int
2189 pppoe_send_event(sessp sp, enum cmd cmdid)
2190 {
2191 	int error;
2192 	struct ng_mesg *msg;
2193 	struct ngpppoe_sts *sts;
2194 
2195 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
2196 
2197 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, cmdid,
2198 			sizeof(struct ngpppoe_sts), M_NOWAIT);
2199 	if (msg == NULL)
2200 		return (ENOMEM);
2201 	sts = (struct ngpppoe_sts *)msg->data;
2202 	strncpy(sts->hook, NG_HOOK_NAME(sp->hook), NG_HOOKSIZ);
2203 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
2204 	return (error);
2205 }
2206