xref: /freebsd/sys/netgraph/ng_pppoe.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
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  * $Whistle: ng_pppoe.c,v 1.10 1999/11/01 09:24:52 julian Exp $
40  */
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/kernel.h>
45 #include <sys/ktr.h>
46 #include <sys/mbuf.h>
47 #include <sys/malloc.h>
48 #include <sys/errno.h>
49 #include <sys/epoch.h>
50 #include <sys/socket.h>
51 #include <sys/sysctl.h>
52 #include <sys/syslog.h>
53 #include <net/ethernet.h>
54 #include <net/if.h>
55 #include <net/if_vlan_var.h>
56 #include <net/vnet.h>
57 
58 #include <netgraph/ng_message.h>
59 #include <netgraph/netgraph.h>
60 #include <netgraph/ng_parse.h>
61 #include <netgraph/ng_pppoe.h>
62 #include <netgraph/ng_ether.h>
63 
64 #ifdef NG_SEPARATE_MALLOC
65 static MALLOC_DEFINE(M_NETGRAPH_PPPOE, "netgraph_pppoe", "netgraph pppoe node");
66 #else
67 #define M_NETGRAPH_PPPOE M_NETGRAPH
68 #endif
69 
70 /* Some PPP protocol numbers we're interested in */
71 #define PROT_LCP		0xc021
72 
73 #define SIGNOFF "session closed"
74 
75 VNET_DEFINE_STATIC(u_int32_t, ng_pppoe_lcp_pcp) = 0;
76 #define V_ng_pppoe_lcp_pcp	VNET(ng_pppoe_lcp_pcp)
77 
78 SYSCTL_NODE(_net_graph, OID_AUTO, pppoe, CTLFLAG_RW, 0, "PPPoE");
79 SYSCTL_UINT(_net_graph_pppoe, OID_AUTO, lcp_pcp,
80 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ng_pppoe_lcp_pcp), 0,
81 	"Set PCP for LCP");
82 
83 /*
84  * This section contains the netgraph method declarations for the
85  * pppoe node. These methods define the netgraph pppoe 'type'.
86  */
87 
88 static ng_constructor_t	ng_pppoe_constructor;
89 static ng_rcvmsg_t	ng_pppoe_rcvmsg;
90 static ng_shutdown_t	ng_pppoe_shutdown;
91 static ng_newhook_t	ng_pppoe_newhook;
92 static ng_connect_t	ng_pppoe_connect;
93 static ng_rcvdata_t	ng_pppoe_rcvdata;
94 static ng_rcvdata_t	ng_pppoe_rcvdata_ether;
95 static ng_rcvdata_t	ng_pppoe_rcvdata_debug;
96 static ng_disconnect_t	ng_pppoe_disconnect;
97 
98 /* Parse type for struct ngpppoe_init_data */
99 static const struct ng_parse_struct_field ngpppoe_init_data_type_fields[]
100 	= NG_PPPOE_INIT_DATA_TYPE_INFO;
101 static const struct ng_parse_type ngpppoe_init_data_state_type = {
102 	&ng_parse_struct_type,
103 	&ngpppoe_init_data_type_fields
104 };
105 
106 /* Parse type for struct ngpppoe_sts */
107 static const struct ng_parse_struct_field ng_pppoe_sts_type_fields[]
108 	= NG_PPPOE_STS_TYPE_INFO;
109 static const struct ng_parse_type ng_pppoe_sts_state_type = {
110 	&ng_parse_struct_type,
111 	&ng_pppoe_sts_type_fields
112 };
113 
114 /* List of commands and how to convert arguments to/from ASCII */
115 static const struct ng_cmdlist ng_pppoe_cmds[] = {
116 	{
117 	  NGM_PPPOE_COOKIE,
118 	  NGM_PPPOE_CONNECT,
119 	  "pppoe_connect",
120 	  &ngpppoe_init_data_state_type,
121 	  NULL
122 	},
123 	{
124 	  NGM_PPPOE_COOKIE,
125 	  NGM_PPPOE_LISTEN,
126 	  "pppoe_listen",
127 	  &ngpppoe_init_data_state_type,
128 	  NULL
129 	},
130 	{
131 	  NGM_PPPOE_COOKIE,
132 	  NGM_PPPOE_OFFER,
133 	  "pppoe_offer",
134 	  &ngpppoe_init_data_state_type,
135 	  NULL
136 	},
137 	{
138 	  NGM_PPPOE_COOKIE,
139 	  NGM_PPPOE_SERVICE,
140 	  "pppoe_service",
141 	  &ngpppoe_init_data_state_type,
142 	  NULL
143 	},
144 	{
145 	  NGM_PPPOE_COOKIE,
146 	  NGM_PPPOE_SUCCESS,
147 	  "pppoe_success",
148 	  &ng_pppoe_sts_state_type,
149 	  NULL
150 	},
151 	{
152 	  NGM_PPPOE_COOKIE,
153 	  NGM_PPPOE_FAIL,
154 	  "pppoe_fail",
155 	  &ng_pppoe_sts_state_type,
156 	  NULL
157 	},
158 	{
159 	  NGM_PPPOE_COOKIE,
160 	  NGM_PPPOE_CLOSE,
161 	  "pppoe_close",
162 	  &ng_pppoe_sts_state_type,
163 	  NULL
164 	},
165 	{
166 	  NGM_PPPOE_COOKIE,
167 	  NGM_PPPOE_SETMODE,
168 	  "pppoe_setmode",
169 	  &ng_parse_string_type,
170 	  NULL
171 	},
172 	{
173 	  NGM_PPPOE_COOKIE,
174 	  NGM_PPPOE_GETMODE,
175 	  "pppoe_getmode",
176 	  NULL,
177 	  &ng_parse_string_type
178 	},
179 	{
180 	  NGM_PPPOE_COOKIE,
181 	  NGM_PPPOE_SETENADDR,
182 	  "setenaddr",
183 	  &ng_parse_enaddr_type,
184 	  NULL
185 	},
186 	{
187 	  NGM_PPPOE_COOKIE,
188 	  NGM_PPPOE_SETMAXP,
189 	  "setmaxp",
190 	  &ng_parse_uint16_type,
191 	  NULL
192 	},
193         {
194 	  NGM_PPPOE_COOKIE,
195 	  NGM_PPPOE_SEND_HURL,
196 	  "send_hurl",
197 	  &ngpppoe_init_data_state_type,
198 	  NULL
199         },
200         {
201 	  NGM_PPPOE_COOKIE,
202 	  NGM_PPPOE_SEND_MOTM,
203 	  "send_motm",
204 	  &ngpppoe_init_data_state_type,
205 	  NULL
206         },
207 	{ 0 }
208 };
209 
210 /* Netgraph node type descriptor */
211 static struct ng_type typestruct = {
212 	.version =	NG_ABI_VERSION,
213 	.name =		NG_PPPOE_NODE_TYPE,
214 	.constructor =	ng_pppoe_constructor,
215 	.rcvmsg =	ng_pppoe_rcvmsg,
216 	.shutdown =	ng_pppoe_shutdown,
217 	.newhook =	ng_pppoe_newhook,
218 	.connect =	ng_pppoe_connect,
219 	.rcvdata =	ng_pppoe_rcvdata,
220 	.disconnect =	ng_pppoe_disconnect,
221 	.cmdlist =	ng_pppoe_cmds,
222 };
223 NETGRAPH_INIT(pppoe, &typestruct);
224 
225 /*
226  * States for the session state machine.
227  * These have no meaning if there is no hook attached yet.
228  */
229 enum state {
230     PPPOE_SNONE=0,	/* [both] Initial state */
231     PPPOE_LISTENING,	/* [Daemon] Listening for discover initiation pkt */
232     PPPOE_SINIT,	/* [Client] Sent discovery initiation */
233     PPPOE_PRIMED,	/* [Server] Awaiting PADI from daemon */
234     PPPOE_SOFFER,	/* [Server] Sent offer message  (got PADI)*/
235     PPPOE_SREQ,		/* [Client] Sent a Request */
236     PPPOE_NEWCONNECTED,	/* [Server] Connection established, No data received */
237     PPPOE_CONNECTED,	/* [Both] Connection established, Data received */
238     PPPOE_DEAD		/* [Both] */
239 };
240 
241 #define NUMTAGS 20 /* number of tags we are set up to work with */
242 
243 /*
244  * Information we store for each hook on each node for negotiating the
245  * session. The mbuf and cluster are freed once negotiation has completed.
246  * The whole negotiation block is then discarded.
247  */
248 
249 struct sess_neg {
250 	struct mbuf 		*m; /* holds cluster with last sent packet */
251 	union	packet		*pkt; /* points within the above cluster */
252 	struct callout		handle;   /* see timeout(9) */
253 	u_int			timeout; /* 0,1,2,4,8,16 etc. seconds */
254 	u_int			numtags;
255 	const struct pppoe_tag	*tags[NUMTAGS];
256 	u_int			service_len;
257 	u_int			ac_name_len;
258 	u_int			host_uniq_len;
259 
260 	struct datatag		service;
261 	struct datatag		ac_name;
262 	struct datatag		host_uniq;
263 };
264 typedef struct sess_neg *negp;
265 
266 /*
267  * Session information that is needed after connection.
268  */
269 struct sess_con {
270 	hook_p  		hook;
271 	uint16_t		Session_ID;
272 	enum state		state;
273 	ng_ID_t			creator;	/* who to notify */
274 	struct pppoe_full_hdr	pkt_hdr;	/* used when connected */
275 	negp			neg;		/* used when negotiating */
276 	LIST_ENTRY(sess_con)	sessions;
277 };
278 typedef struct sess_con *sessp;
279 
280 #define SESSHASHSIZE	0x0100
281 #define SESSHASH(x)	(((x) ^ ((x) >> 8)) & (SESSHASHSIZE - 1))
282 
283 struct sess_hash_entry {
284 	struct mtx	mtx;
285 	LIST_HEAD(hhead, sess_con) head;
286 };
287 
288 /*
289  * Information we store for each node
290  */
291 struct PPPoE {
292 	node_p		node;		/* back pointer to node */
293 	hook_p  	ethernet_hook;
294 	hook_p  	debug_hook;
295 	u_int   	packets_in;	/* packets in from ethernet */
296 	u_int   	packets_out;	/* packets out towards ethernet */
297 	uint32_t	flags;
298 #define	COMPAT_3COM	0x00000001
299 #define	COMPAT_DLINK	0x00000002
300 	struct ether_header	eh;
301 	LIST_HEAD(, sess_con) listeners;
302 	struct sess_hash_entry	sesshash[SESSHASHSIZE];
303 	struct maxptag	max_payload;	/* PPP-Max-Payload (RFC4638) */
304 };
305 typedef struct PPPoE *priv_p;
306 
307 union uniq {
308 	char bytes[sizeof(void *)];
309 	void *pointer;
310 };
311 
312 #define	LEAVE(x) do { error = x; goto quit; } while(0)
313 static void	pppoe_start(sessp sp);
314 static void	pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2);
315 static const	struct pppoe_tag *scan_tags(sessp sp,
316 			const struct pppoe_hdr* ph);
317 static	int	pppoe_send_event(sessp sp, enum cmd cmdid);
318 
319 /*************************************************************************
320  * Some basic utilities  from the Linux version with author's permission.*
321  * Author:	Michal Ostrowski <mostrows@styx.uwaterloo.ca>		 *
322  ************************************************************************/
323 
324 /*
325  * Return the location where the next tag can be put
326  */
327 static __inline const struct pppoe_tag*
328 next_tag(const struct pppoe_hdr* ph)
329 {
330 	return (const struct pppoe_tag*)(((const char*)(ph + 1))
331 	    + ntohs(ph->length));
332 }
333 
334 /*
335  * Look for a tag of a specific type.
336  * Don't trust any length the other end says,
337  * but assume we already sanity checked ph->length.
338  */
339 static const struct pppoe_tag*
340 get_tag(const struct pppoe_hdr* ph, uint16_t idx)
341 {
342 	const char *const end = (const char *)next_tag(ph);
343 	const struct pppoe_tag *pt = (const void *)(ph + 1);
344 	const char *ptn;
345 
346 	/*
347 	 * Keep processing tags while a tag header will still fit.
348 	 */
349 	while((const char*)(pt + 1) <= end) {
350 		/*
351 		 * If the tag data would go past the end of the packet, abort.
352 		 */
353 		ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
354 		if (ptn > end) {
355 			CTR2(KTR_NET, "%20s: invalid length for tag %d",
356 			    __func__, idx);
357 			return (NULL);
358 		}
359 		if (pt->tag_type == idx) {
360 			CTR2(KTR_NET, "%20s: found tag %d", __func__, idx);
361 			return (pt);
362 		}
363 
364 		pt = (const struct pppoe_tag*)ptn;
365 	}
366 
367 	CTR2(KTR_NET, "%20s: not found tag %d", __func__, idx);
368 	return (NULL);
369 }
370 
371 /**************************************************************************
372  * Inlines to initialise or add tags to a session's tag list.
373  **************************************************************************/
374 /*
375  * Initialise the session's tag list.
376  */
377 static void
378 init_tags(sessp sp)
379 {
380 	KASSERT(sp->neg != NULL, ("%s: no neg", __func__));
381 	sp->neg->numtags = 0;
382 }
383 
384 static void
385 insert_tag(sessp sp, const struct pppoe_tag *tp)
386 {
387 	negp neg = sp->neg;
388 	int i;
389 
390 	KASSERT(neg != NULL, ("%s: no neg", __func__));
391 	if ((i = neg->numtags++) < NUMTAGS) {
392 		neg->tags[i] = tp;
393 	} else {
394 		log(LOG_NOTICE, "ng_pppoe: asked to add too many tags to "
395 		    "packet\n");
396 		neg->numtags--;
397 	}
398 }
399 
400 /*
401  * Make up a packet, using the tags filled out for the session.
402  *
403  * Assume that the actual pppoe header and ethernet header
404  * are filled out externally to this routine.
405  * Also assume that neg->wh points to the correct
406  * location at the front of the buffer space.
407  */
408 static void
409 make_packet(sessp sp) {
410 	struct pppoe_full_hdr *wh = &sp->neg->pkt->pkt_header;
411 	const struct pppoe_tag **tag;
412 	char *dp;
413 	int count;
414 	int tlen;
415 	uint16_t length = 0;
416 
417 	KASSERT((sp->neg != NULL) && (sp->neg->m != NULL),
418 	    ("%s: called from wrong state", __func__));
419 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
420 
421 	dp = (char *)(&wh->ph + 1);
422 	for (count = 0, tag = sp->neg->tags;
423 	    ((count < sp->neg->numtags) && (count < NUMTAGS));
424 	    tag++, count++) {
425 		tlen = ntohs((*tag)->tag_len) + sizeof(**tag);
426 		if ((length + tlen) > (ETHER_MAX_LEN - 4 - sizeof(*wh))) {
427 			log(LOG_NOTICE, "ng_pppoe: tags too long\n");
428 			sp->neg->numtags = count;
429 			break;	/* XXX chop off what's too long */
430 		}
431 		bcopy(*tag, (char *)dp, tlen);
432 		length += tlen;
433 		dp += tlen;
434 	}
435  	wh->ph.length = htons(length);
436 	sp->neg->m->m_len = length + sizeof(*wh);
437 	sp->neg->m->m_pkthdr.len = length + sizeof(*wh);
438 }
439 
440 /**************************************************************************
441  * Routines to match a service.						  *
442  **************************************************************************/
443 
444 /*
445  * Find a hook that has a service string that matches that
446  * we are seeking. For now use a simple string.
447  * In the future we may need something like regexp().
448  *
449  * Null string is a wildcard (ANY service), according to RFC2516.
450  * And historical FreeBSD wildcard is also "*".
451  */
452 
453 static hook_p
454 pppoe_match_svc(node_p node, const struct pppoe_tag *tag)
455 {
456 	const priv_p privp = NG_NODE_PRIVATE(node);
457 	sessp sp;
458 
459 	LIST_FOREACH(sp, &privp->listeners, sessions) {
460 		negp neg = sp->neg;
461 
462 		/* Empty Service-Name matches any service. */
463 		if (neg->service_len == 0)
464 			break;
465 
466 		/* Special case for a blank or "*" service name (wildcard). */
467 		if (neg->service_len == 1 && neg->service.data[0] == '*')
468 			break;
469 
470 		/* If the lengths don't match, that aint it. */
471 		if (neg->service_len != ntohs(tag->tag_len))
472 			continue;
473 
474 		if (strncmp((const char *)(tag + 1), neg->service.data,
475 		    ntohs(tag->tag_len)) == 0)
476 			break;
477 	}
478 	CTR3(KTR_NET, "%20s: matched %p for %s", __func__,
479 	    sp?sp->hook:NULL, (const char *)(tag + 1));
480 
481 	return (sp?sp->hook:NULL);
482 }
483 
484 /*
485  * Broadcast the PADI packet in m0 to all listening hooks.
486  * This routine is called when a PADI with empty Service-Name
487  * tag is received. Client should receive PADOs with all
488  * available services.
489  */
490 static int
491 pppoe_broadcast_padi(node_p node, struct mbuf *m0)
492 {
493 	const priv_p privp = NG_NODE_PRIVATE(node);
494 	sessp sp;
495 	int error = 0;
496 
497 	LIST_FOREACH(sp, &privp->listeners, sessions) {
498 		struct mbuf *m;
499 
500 		m = m_dup(m0, M_NOWAIT);
501 		if (m == NULL)
502 			return (ENOMEM);
503 		NG_SEND_DATA_ONLY(error, sp->hook, m);
504 		if (error)
505 			return (error);
506 	}
507 
508 	return (0);
509 }
510 
511 /*
512  * Find a hook, which name equals to given service.
513  */
514 static hook_p
515 pppoe_find_svc(node_p node, const char *svc_name, int svc_len)
516 {
517 	const priv_p privp = NG_NODE_PRIVATE(node);
518 	sessp sp;
519 
520 	LIST_FOREACH(sp, &privp->listeners, sessions) {
521 		negp neg = sp->neg;
522 
523 		if (neg->service_len == svc_len &&
524 		    strncmp(svc_name, neg->service.data, svc_len) == 0)
525 			return (sp->hook);
526 	}
527 
528 	return (NULL);
529 }
530 
531 /**************************************************************************
532  * Routines to find a particular session that matches an incoming packet. *
533  **************************************************************************/
534 /* Find free session and add to hash. */
535 static uint16_t
536 pppoe_getnewsession(sessp sp)
537 {
538 	const priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
539 	static uint16_t pppoe_sid = 1;
540 	sessp	tsp;
541 	uint16_t val, hash;
542 
543 restart:
544 	/* Atomicity is not needed here as value will be checked. */
545 	val = pppoe_sid++;
546 	/* Spec says 0xFFFF is reserved, also don't use 0x0000. */
547 	if (val == 0xffff || val == 0x0000)
548 		val = pppoe_sid = 1;
549 
550 	/* Check it isn't already in use. */
551 	hash = SESSHASH(val);
552 	mtx_lock(&privp->sesshash[hash].mtx);
553 	LIST_FOREACH(tsp, &privp->sesshash[hash].head, sessions) {
554 		if (tsp->Session_ID == val)
555 			break;
556 	}
557 	if (!tsp) {
558 		sp->Session_ID = val;
559 		LIST_INSERT_HEAD(&privp->sesshash[hash].head, sp, sessions);
560 	}
561 	mtx_unlock(&privp->sesshash[hash].mtx);
562 	if (tsp)
563 		goto restart;
564 
565 	CTR2(KTR_NET, "%20s: new sid %d", __func__, val);
566 
567 	return (val);
568 }
569 
570 /* Add specified session to hash. */
571 static void
572 pppoe_addsession(sessp sp)
573 {
574 	const priv_p	privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
575 	uint16_t	hash = SESSHASH(sp->Session_ID);
576 
577 	mtx_lock(&privp->sesshash[hash].mtx);
578 	LIST_INSERT_HEAD(&privp->sesshash[hash].head, sp, sessions);
579 	mtx_unlock(&privp->sesshash[hash].mtx);
580 }
581 
582 /* Delete specified session from hash. */
583 static void
584 pppoe_delsession(sessp sp)
585 {
586 	const priv_p	privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
587 	uint16_t	hash = SESSHASH(sp->Session_ID);
588 
589 	mtx_lock(&privp->sesshash[hash].mtx);
590 	LIST_REMOVE(sp, sessions);
591 	mtx_unlock(&privp->sesshash[hash].mtx);
592 }
593 
594 /* Find matching peer/session combination. */
595 static sessp
596 pppoe_findsession(priv_p privp, const struct pppoe_full_hdr *wh)
597 {
598 	uint16_t 	session = ntohs(wh->ph.sid);
599 	uint16_t	hash = SESSHASH(session);
600 	sessp		sp = NULL;
601 
602 	mtx_lock(&privp->sesshash[hash].mtx);
603 	LIST_FOREACH(sp, &privp->sesshash[hash].head, sessions) {
604 		if (sp->Session_ID == session &&
605 		    bcmp(sp->pkt_hdr.eh.ether_dhost,
606 		     wh->eh.ether_shost, ETHER_ADDR_LEN) == 0) {
607 			break;
608 		}
609 	}
610 	mtx_unlock(&privp->sesshash[hash].mtx);
611 	CTR3(KTR_NET, "%20s: matched %p for %d", __func__, sp?sp->hook:NULL,
612 	    session);
613 
614 	return (sp);
615 }
616 
617 static hook_p
618 pppoe_finduniq(node_p node, const struct pppoe_tag *tag)
619 {
620 	hook_p	hook = NULL;
621 	sessp	sp;
622 
623 	/* Cycle through all known hooks. */
624 	LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
625 		/* Skip any nonsession hook. */
626 		if (NG_HOOK_PRIVATE(hook) == NULL)
627 			continue;
628 		sp = NG_HOOK_PRIVATE(hook);
629 		/* Skip already connected sessions. */
630 		if (sp->neg == NULL)
631 			continue;
632 		if (sp->neg->host_uniq_len == ntohs(tag->tag_len) &&
633 		    bcmp(sp->neg->host_uniq.data, (const char *)(tag + 1),
634 		     sp->neg->host_uniq_len) == 0)
635 			break;
636 	}
637 	CTR3(KTR_NET, "%20s: matched %p for %p", __func__, hook, sp);
638 
639 	return (hook);
640 }
641 
642 static hook_p
643 pppoe_findcookie(node_p node, const struct pppoe_tag *tag)
644 {
645 	hook_p	hook = NULL;
646 	union uniq cookie;
647 
648 	bcopy(tag + 1, cookie.bytes, sizeof(void *));
649 	/* Cycle through all known hooks. */
650 	LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
651 		/* Skip any nonsession hook. */
652 		if (NG_HOOK_PRIVATE(hook) == NULL)
653 			continue;
654 		if (cookie.pointer == NG_HOOK_PRIVATE(hook))
655 			break;
656 	}
657 	CTR3(KTR_NET, "%20s: matched %p for %p", __func__, hook, cookie.pointer);
658 
659 	return (hook);
660 }
661 
662 /**************************************************************************
663  * Start of Netgraph entrypoints.					  *
664  **************************************************************************/
665 
666 /*
667  * Allocate the private data structure and link it with node.
668  */
669 static int
670 ng_pppoe_constructor(node_p node)
671 {
672 	priv_p	privp;
673 	int	i;
674 
675 	/* Initialize private descriptor. */
676 	privp = malloc(sizeof(*privp), M_NETGRAPH_PPPOE, M_WAITOK | M_ZERO);
677 
678 	/* Link structs together; this counts as our one reference to *node. */
679 	NG_NODE_SET_PRIVATE(node, privp);
680 	privp->node = node;
681 
682 	/* Initialize to standard mode. */
683 	memset(&privp->eh.ether_dhost, 0xff, ETHER_ADDR_LEN);
684 	privp->eh.ether_type = ETHERTYPE_PPPOE_DISC;
685 
686 	LIST_INIT(&privp->listeners);
687 	for (i = 0; i < SESSHASHSIZE; i++) {
688 	    mtx_init(&privp->sesshash[i].mtx, "PPPoE hash mutex", NULL, MTX_DEF);
689 	    LIST_INIT(&privp->sesshash[i].head);
690 	}
691 
692 	CTR3(KTR_NET, "%20s: created node [%x] (%p)",
693 	    __func__, node->nd_ID, node);
694 
695 	return (0);
696 }
697 
698 /*
699  * Give our ok for a hook to be added...
700  * point the hook's private info to the hook structure.
701  *
702  * The following hook names are special:
703  *  "ethernet":  the hook that should be connected to a NIC.
704  *  "debug":	copies of data sent out here  (when I write the code).
705  * All other hook names need only be unique. (the framework checks this).
706  */
707 static int
708 ng_pppoe_newhook(node_p node, hook_p hook, const char *name)
709 {
710 	const priv_p privp = NG_NODE_PRIVATE(node);
711 	sessp sp;
712 
713 	if (strcmp(name, NG_PPPOE_HOOK_ETHERNET) == 0) {
714 		privp->ethernet_hook = hook;
715 		NG_HOOK_SET_RCVDATA(hook, ng_pppoe_rcvdata_ether);
716 	} else if (strcmp(name, NG_PPPOE_HOOK_DEBUG) == 0) {
717 		privp->debug_hook = hook;
718 		NG_HOOK_SET_RCVDATA(hook, ng_pppoe_rcvdata_debug);
719 	} else {
720 		/*
721 		 * Any other unique name is OK.
722 		 * The infrastructure has already checked that it's unique,
723 		 * so just allocate it and hook it in.
724 		 */
725 		sp = malloc(sizeof(*sp), M_NETGRAPH_PPPOE, M_NOWAIT | M_ZERO);
726 		if (sp == NULL)
727 			return (ENOMEM);
728 
729 		NG_HOOK_SET_PRIVATE(hook, sp);
730 		sp->hook = hook;
731 	}
732 	CTR5(KTR_NET, "%20s: node [%x] (%p) connected hook %s (%p)",
733 	    __func__, node->nd_ID, node, name, hook);
734 
735 	return(0);
736 }
737 
738 /*
739  * Hook has been added successfully. Request the MAC address of
740  * the underlying Ethernet node.
741  */
742 static int
743 ng_pppoe_connect(hook_p hook)
744 {
745 	const priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
746 	struct ng_mesg *msg;
747 	int error;
748 
749 	if (hook != privp->ethernet_hook)
750 		return (0);
751 
752 	/*
753 	 * If this is Ethernet hook, then request MAC address
754 	 * from our downstream.
755 	 */
756 	NG_MKMESSAGE(msg, NGM_ETHER_COOKIE, NGM_ETHER_GET_ENADDR, 0, M_NOWAIT);
757 	if (msg == NULL)
758 		return (ENOBUFS);
759 
760 	/*
761 	 * Our hook and peer hook have HK_INVALID flag set,
762 	 * so we can't use NG_SEND_MSG_HOOK() macro here.
763 	 */
764 	NG_SEND_MSG_ID(error, privp->node, msg,
765 	    NG_NODE_ID(NG_PEER_NODE(privp->ethernet_hook)),
766 	    NG_NODE_ID(privp->node));
767 
768 	return (error);
769 }
770 /*
771  * Get a netgraph control message.
772  * Check it is one we understand. If needed, send a response.
773  * We sometimes save the address for an async action later.
774  * Always free the message.
775  */
776 static int
777 ng_pppoe_rcvmsg(node_p node, item_p item, hook_p lasthook)
778 {
779 	struct epoch_tracker et;
780 	priv_p privp = NG_NODE_PRIVATE(node);
781 	struct ngpppoe_init_data *ourmsg = NULL;
782 	struct ng_mesg *resp = NULL;
783 	int error = 0;
784 	hook_p hook = NULL;
785 	sessp sp = NULL;
786 	negp neg = NULL;
787 	struct ng_mesg *msg;
788 
789 	NGI_GET_MSG(item, msg);
790 	CTR5(KTR_NET, "%20s: node [%x] (%p) got message %d with cookie %d",
791 	    __func__, node->nd_ID, node, msg->header.cmd,
792 	    msg->header.typecookie);
793 
794 	/* Deal with message according to cookie and command. */
795 	switch (msg->header.typecookie) {
796 	case NGM_PPPOE_COOKIE:
797 		switch (msg->header.cmd) {
798 		case NGM_PPPOE_CONNECT:
799 		case NGM_PPPOE_LISTEN:
800 		case NGM_PPPOE_OFFER:
801 		case NGM_PPPOE_SERVICE:
802 		case NGM_PPPOE_SEND_HURL:
803 		case NGM_PPPOE_SEND_MOTM:
804 			ourmsg = (struct ngpppoe_init_data *)msg->data;
805 			if (msg->header.arglen < sizeof(*ourmsg)) {
806 				log(LOG_ERR, "ng_pppoe[%x]: init data too "
807 				    "small\n", node->nd_ID);
808 				LEAVE(EMSGSIZE);
809 			}
810 			if (msg->header.cmd == NGM_PPPOE_SEND_HURL ||
811 			    msg->header.cmd == NGM_PPPOE_SEND_MOTM) {
812 				if (msg->header.arglen - sizeof(*ourmsg) >
813 				    PPPOE_PADM_VALUE_SIZE) {
814 					log(LOG_ERR, "ng_pppoe[%x]: message "
815 					    "too big\n", node->nd_ID);
816 					LEAVE(EMSGSIZE);
817 				}
818 			} else {
819 				if (msg->header.arglen - sizeof(*ourmsg) >
820 				    PPPOE_SERVICE_NAME_SIZE) {
821 					log(LOG_ERR, "ng_pppoe[%x]: service name "
822 					    "too big\n", node->nd_ID);
823 					LEAVE(EMSGSIZE);
824 				}
825 			}
826 			if (msg->header.arglen - sizeof(*ourmsg) <
827 			    ourmsg->data_len) {
828 				log(LOG_ERR, "ng_pppoe[%x]: init data has bad "
829 				    "length, %d should be %zd\n", node->nd_ID,
830 				    ourmsg->data_len,
831 				    msg->header.arglen - sizeof (*ourmsg));
832 				LEAVE(EMSGSIZE);
833 			}
834 
835 			/* Make sure strcmp will terminate safely. */
836 			ourmsg->hook[sizeof(ourmsg->hook) - 1] = '\0';
837 
838 			/* Find hook by name. */
839 			hook = ng_findhook(node, ourmsg->hook);
840 			if (hook == NULL)
841 				LEAVE(ENOENT);
842 
843 			sp = NG_HOOK_PRIVATE(hook);
844 			if (sp == NULL)
845 				LEAVE(EINVAL);
846 
847 			if (msg->header.cmd == NGM_PPPOE_LISTEN) {
848 				/*
849 				 * Ensure we aren't already listening for this
850 				 * service.
851 				 */
852 				if (pppoe_find_svc(node, ourmsg->data,
853 				    ourmsg->data_len) != NULL)
854 					LEAVE(EEXIST);
855 			}
856 
857 			/*
858 			 * PPPOE_SERVICE advertisements are set up
859 			 * on sessions that are in PRIMED state.
860 			 */
861 			if (msg->header.cmd == NGM_PPPOE_SERVICE)
862 				break;
863 
864 			/*
865 			 * PADM messages are set up on active sessions.
866 			 */
867 			if (msg->header.cmd == NGM_PPPOE_SEND_HURL ||
868 			    msg->header.cmd == NGM_PPPOE_SEND_MOTM) {
869 				if (sp->state != PPPOE_NEWCONNECTED &&
870 				    sp->state != PPPOE_CONNECTED) {
871 					log(LOG_NOTICE, "ng_pppoe[%x]: session is not "
872 					    "active\n", node->nd_ID);
873 					LEAVE(EISCONN);
874 				}
875 				break;
876 			}
877 
878 			if (sp->state != PPPOE_SNONE) {
879 				log(LOG_NOTICE, "ng_pppoe[%x]: Session already "
880 				    "active\n", node->nd_ID);
881 				LEAVE(EISCONN);
882 			}
883 
884 			/*
885 			 * Set up prototype header.
886 			 */
887 			neg = malloc(sizeof(*neg), M_NETGRAPH_PPPOE,
888 			    M_NOWAIT | M_ZERO);
889 
890 			if (neg == NULL)
891 				LEAVE(ENOMEM);
892 
893 			neg->m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
894 			if (neg->m == NULL) {
895 				free(neg, M_NETGRAPH_PPPOE);
896 				LEAVE(ENOBUFS);
897 			}
898 			neg->m->m_pkthdr.rcvif = NULL;
899 			sp->neg = neg;
900 			ng_callout_init(&neg->handle);
901 			neg->m->m_len = sizeof(struct pppoe_full_hdr);
902 			neg->pkt = mtod(neg->m, union packet*);
903 			memcpy((void *)&neg->pkt->pkt_header.eh,
904 			    &privp->eh, sizeof(struct ether_header));
905 			neg->pkt->pkt_header.ph.ver = 0x1;
906 			neg->pkt->pkt_header.ph.type = 0x1;
907 			neg->pkt->pkt_header.ph.sid = 0x0000;
908 			neg->timeout = 0;
909 
910 			sp->creator = NGI_RETADDR(item);
911 		}
912 		switch (msg->header.cmd) {
913 		case NGM_PPPOE_GET_STATUS:
914 		    {
915 			struct ngpppoestat *stats;
916 
917 			NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT);
918 			if (!resp)
919 				LEAVE(ENOMEM);
920 
921 			stats = (struct ngpppoestat *) resp->data;
922 			stats->packets_in = privp->packets_in;
923 			stats->packets_out = privp->packets_out;
924 			break;
925 		    }
926 		case NGM_PPPOE_CONNECT:
927 		    {
928 			/*
929 			 * Check the hook exists and is Uninitialised.
930 			 * Send a PADI request, and start the timeout logic.
931 			 * Store the originator of this message so we can send
932 			 * a success or fail message to them later.
933 			 * Move the session to SINIT.
934 			 * Set up the session to the correct state and
935 			 * start it.
936 			 */
937 			int	acnpos, acnlen = 0, acnsep = 0;
938 			int	hupos, hulen = 0, husep = 0;
939 			int	i, srvpos, srvlen;
940 			acnpos = 0;
941 			for (i = 0; i < ourmsg->data_len; i++) {
942 				if (ourmsg->data[i] == '\\') {
943 					acnlen = i;
944 					acnsep = 1;
945 					break;
946 				}
947 			}
948 			hupos = acnlen + acnsep;
949 			for (i = hupos; i < ourmsg->data_len; i++) {
950 				if (ourmsg->data[i] == '|') {
951 					hulen = i - hupos;
952 					husep = 1;
953 					break;
954 				}
955 			}
956 			srvpos = hupos + hulen + husep;
957 			srvlen = ourmsg->data_len - srvpos;
958 
959 			bcopy(ourmsg->data + acnpos, neg->ac_name.data, acnlen);
960 			neg->ac_name_len = acnlen;
961 
962 			neg->host_uniq.hdr.tag_type = PTT_HOST_UNIQ;
963 			if (hulen == 0) {
964 				/* Not provided, generate one */
965 				neg->host_uniq.hdr.tag_len = htons(sizeof(sp));
966 				bcopy(&sp, neg->host_uniq.data, sizeof(sp));
967 				neg->host_uniq_len = sizeof(sp);
968 			} else if (hulen > 2 && ourmsg->data[hupos] == '0' &&
969 			  ourmsg->data[hupos + 1] == 'x' && hulen % 2 == 0) {
970 				/* Hex encoded */
971 				static const char hexdig[16] = "0123456789abcdef";
972 				int j;
973 
974 				neg->host_uniq.hdr.tag_len = htons((uint16_t)(hulen / 2 - 1));
975 				for (i = 0; i < hulen - 2; i++) {
976 					for (j = 0;
977 					     j < 16 &&
978 					     ourmsg->data[hupos + 2 + i] != hexdig[j];
979 					     j++);
980 					if (j == 16)
981 						LEAVE(EINVAL);
982 					if (i % 2 == 0)
983 						neg->host_uniq.data[i / 2] = j << 4;
984 					else
985 						neg->host_uniq.data[i / 2] |= j;
986 				}
987 				neg->host_uniq_len = hulen / 2 - 1;
988 			} else {
989 				/* Plain string */
990 				neg->host_uniq.hdr.tag_len = htons((uint16_t)hulen);
991 				bcopy(ourmsg->data + hupos, neg->host_uniq.data, hulen);
992 				neg->host_uniq_len = hulen;
993 			}
994 
995 			neg->service.hdr.tag_type = PTT_SRV_NAME;
996 			neg->service.hdr.tag_len = htons((uint16_t)srvlen);
997 			bcopy(ourmsg->data + srvpos, neg->service.data, srvlen);
998 			neg->service_len = srvlen;
999 			NET_EPOCH_ENTER(et);
1000 			pppoe_start(sp);
1001 			NET_EPOCH_EXIT(et);
1002 			break;
1003 		    }
1004 		case NGM_PPPOE_LISTEN:
1005 			/*
1006 			 * Check the hook exists and is Uninitialised.
1007 			 * Install the service matching string.
1008 			 * Store the originator of this message so we can send
1009 			 * a success or fail message to them later.
1010 			 * Move the hook to 'LISTENING'
1011 			 */
1012 			neg->service.hdr.tag_type = PTT_SRV_NAME;
1013 			neg->service.hdr.tag_len =
1014 			    htons((uint16_t)ourmsg->data_len);
1015 
1016 			if (ourmsg->data_len)
1017 				bcopy(ourmsg->data, neg->service.data,
1018 				    ourmsg->data_len);
1019 			neg->service_len = ourmsg->data_len;
1020 			neg->pkt->pkt_header.ph.code = PADT_CODE;
1021 			/*
1022 			 * Wait for PADI packet coming from Ethernet.
1023 			 */
1024 			sp->state = PPPOE_LISTENING;
1025 			LIST_INSERT_HEAD(&privp->listeners, sp, sessions);
1026 			break;
1027 		case NGM_PPPOE_OFFER:
1028 			/*
1029 			 * Check the hook exists and is Uninitialised.
1030 			 * Store the originator of this message so we can send
1031 			 * a success of fail message to them later.
1032 			 * Store the AC-Name given and go to PRIMED.
1033 			 */
1034 			neg->ac_name.hdr.tag_type = PTT_AC_NAME;
1035 			neg->ac_name.hdr.tag_len =
1036 			    htons((uint16_t)ourmsg->data_len);
1037 			if (ourmsg->data_len)
1038 				bcopy(ourmsg->data, neg->ac_name.data,
1039 				    ourmsg->data_len);
1040 			neg->ac_name_len = ourmsg->data_len;
1041 			neg->pkt->pkt_header.ph.code = PADO_CODE;
1042 			/*
1043 			 * Wait for PADI packet coming from hook.
1044 			 */
1045 			sp->state = PPPOE_PRIMED;
1046 			break;
1047 		case NGM_PPPOE_SERVICE:
1048 			/*
1049 			 * Check the session is primed.
1050 			 * for now just allow ONE service to be advertised.
1051 			 * If you do it twice you just overwrite.
1052 			 */
1053 			if (sp->state != PPPOE_PRIMED) {
1054 				log(LOG_NOTICE, "ng_pppoe[%x]: session not "
1055 				    "primed\n", node->nd_ID);
1056 				LEAVE(EISCONN);
1057 			}
1058 			neg = sp->neg;
1059 			neg->service.hdr.tag_type = PTT_SRV_NAME;
1060 			neg->service.hdr.tag_len =
1061 			    htons((uint16_t)ourmsg->data_len);
1062 
1063 			if (ourmsg->data_len)
1064 				bcopy(ourmsg->data, neg->service.data,
1065 				    ourmsg->data_len);
1066 			neg->service_len = ourmsg->data_len;
1067 			break;
1068 		case NGM_PPPOE_SETMODE:
1069 		    {
1070 			char *s;
1071 			size_t len;
1072 
1073 			if (msg->header.arglen == 0)
1074 				LEAVE(EINVAL);
1075 
1076 			s = (char *)msg->data;
1077 			len = msg->header.arglen - 1;
1078 
1079 			/* Search for matching mode string. */
1080 			if (len == strlen(NG_PPPOE_STANDARD) &&
1081 			    (strncmp(NG_PPPOE_STANDARD, s, len) == 0)) {
1082 				privp->flags = 0;
1083 				privp->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1084 				break;
1085 			}
1086 			if (len == strlen(NG_PPPOE_3COM) &&
1087 			    (strncmp(NG_PPPOE_3COM, s, len) == 0)) {
1088 				privp->flags |= COMPAT_3COM;
1089 				privp->eh.ether_type =
1090 				    ETHERTYPE_PPPOE_3COM_DISC;
1091 				break;
1092 			}
1093 			if (len == strlen(NG_PPPOE_DLINK) &&
1094 			    (strncmp(NG_PPPOE_DLINK, s, len) == 0)) {
1095 				privp->flags |= COMPAT_DLINK;
1096 				break;
1097 			}
1098 			error = EINVAL;
1099 			break;
1100 		    }
1101 		case NGM_PPPOE_GETMODE:
1102 		    {
1103 			char *s;
1104 			size_t len = 0;
1105 
1106 			if (privp->flags == 0)
1107 				len += strlen(NG_PPPOE_STANDARD) + 1;
1108 			if (privp->flags & COMPAT_3COM)
1109 				len += strlen(NG_PPPOE_3COM) + 1;
1110 			if (privp->flags & COMPAT_DLINK)
1111 				len += strlen(NG_PPPOE_DLINK) + 1;
1112 
1113 			NG_MKRESPONSE(resp, msg, len, M_NOWAIT);
1114 			if (resp == NULL)
1115 				LEAVE(ENOMEM);
1116 
1117 			s = (char *)resp->data;
1118 			if (privp->flags == 0) {
1119 				len = strlen(NG_PPPOE_STANDARD);
1120 				strlcpy(s, NG_PPPOE_STANDARD, len + 1);
1121 				break;
1122 			}
1123 			if (privp->flags & COMPAT_3COM) {
1124 				len = strlen(NG_PPPOE_3COM);
1125 				strlcpy(s, NG_PPPOE_3COM, len + 1);
1126 				s += len;
1127 			}
1128 			if (privp->flags & COMPAT_DLINK) {
1129 				if (s != resp->data)
1130 					*s++ = '|';
1131 				len = strlen(NG_PPPOE_DLINK);
1132 				strlcpy(s, NG_PPPOE_DLINK, len + 1);
1133 			}
1134 			break;
1135 		    }
1136 		case NGM_PPPOE_SETENADDR:
1137 			if (msg->header.arglen != ETHER_ADDR_LEN)
1138 				LEAVE(EINVAL);
1139 			bcopy(msg->data, &privp->eh.ether_shost,
1140 			    ETHER_ADDR_LEN);
1141 			break;
1142 		case NGM_PPPOE_SETMAXP:
1143 			if (msg->header.arglen != sizeof(uint16_t))
1144 				LEAVE(EINVAL);
1145 			privp->max_payload.hdr.tag_type = PTT_MAX_PAYL;
1146 			privp->max_payload.hdr.tag_len = htons(sizeof(uint16_t));
1147 			privp->max_payload.data = htons(*((uint16_t *)msg->data));
1148 			break;
1149 		case NGM_PPPOE_SEND_HURL:
1150 		    {
1151 			struct mbuf *m;
1152 
1153 			/* Generate a packet of that type. */
1154 			m = m_gethdr(M_NOWAIT, MT_DATA);
1155 			if (m == NULL)
1156 				log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
1157 				    "mbufs\n", node->nd_ID);
1158 			else {
1159 				struct pppoe_full_hdr *wh;
1160 				struct pppoe_tag *tag;
1161 				int     error = 0;
1162 
1163 				wh = mtod(m, struct pppoe_full_hdr *);
1164 				bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1165 
1166 				/* Revert the stored header to DISC/PADM mode. */
1167 				wh->ph.code = PADM_CODE;
1168 				/*
1169 				 * Configure ethertype depending on what
1170 				 * was used during sessions stage.
1171 				 */
1172 				if (wh->eh.ether_type ==
1173 				    ETHERTYPE_PPPOE_3COM_SESS)
1174 					wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
1175 				else
1176 					wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1177 				/*
1178 				 * Add PADM message and adjust sizes.
1179 				 */
1180 				tag = (void *)(&wh->ph + 1);
1181 				tag->tag_type = PTT_HURL;
1182 				tag->tag_len = htons(ourmsg->data_len);
1183 				strncpy((char *)(tag + 1), ourmsg->data, ourmsg->data_len);
1184 				m->m_pkthdr.len = m->m_len = sizeof(*wh) + sizeof(*tag) +
1185 				    ourmsg->data_len;
1186 				wh->ph.length = htons(sizeof(*tag) + ourmsg->data_len);
1187 				NET_EPOCH_ENTER(et);
1188 				NG_SEND_DATA_ONLY(error,
1189 				    privp->ethernet_hook, m);
1190 				NET_EPOCH_EXIT(et);
1191 			}
1192 			break;
1193 		    }
1194 		case NGM_PPPOE_SEND_MOTM:
1195 		    {
1196 			struct mbuf *m;
1197 
1198 			/* Generate a packet of that type. */
1199 			m = m_gethdr(M_NOWAIT, MT_DATA);
1200 			if (m == NULL)
1201 				log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
1202 				    "mbufs\n", node->nd_ID);
1203 			else {
1204 				struct pppoe_full_hdr *wh;
1205 				struct pppoe_tag *tag;
1206 				int     error = 0;
1207 
1208 				wh = mtod(m, struct pppoe_full_hdr *);
1209 				bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1210 
1211 				/* Revert the stored header to DISC/PADM mode. */
1212 				wh->ph.code = PADM_CODE;
1213 				/*
1214 				 * Configure ethertype depending on what
1215 				 * was used during sessions stage.
1216 				 */
1217 				if (wh->eh.ether_type ==
1218 				    ETHERTYPE_PPPOE_3COM_SESS)
1219 					wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
1220 				else
1221 					wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1222 				/*
1223 				 * Add PADM message and adjust sizes.
1224 				 */
1225 				tag = (void *)(&wh->ph + 1);
1226 				tag->tag_type = PTT_MOTM;
1227 				tag->tag_len = htons(ourmsg->data_len);
1228 				strncpy((char *)(tag + 1), ourmsg->data, ourmsg->data_len);
1229 				m->m_pkthdr.len = m->m_len = sizeof(*wh) + sizeof(*tag) +
1230 				    ourmsg->data_len;
1231 				wh->ph.length = htons(sizeof(*tag) + ourmsg->data_len);
1232 				NET_EPOCH_ENTER(et);
1233 				NG_SEND_DATA_ONLY(error,
1234 				    privp->ethernet_hook, m);
1235 				NET_EPOCH_EXIT(et);
1236 			}
1237 			break;
1238 		    }
1239 		default:
1240 			LEAVE(EINVAL);
1241 		}
1242 		break;
1243 	case NGM_ETHER_COOKIE:
1244 		if (!(msg->header.flags & NGF_RESP))
1245 			LEAVE(EINVAL);
1246 		switch (msg->header.cmd) {
1247 		case NGM_ETHER_GET_ENADDR:
1248 			if (msg->header.arglen != ETHER_ADDR_LEN)
1249 				LEAVE(EINVAL);
1250 			bcopy(msg->data, &privp->eh.ether_shost,
1251 			    ETHER_ADDR_LEN);
1252 			break;
1253 		default:
1254 			LEAVE(EINVAL);
1255 		}
1256 		break;
1257 	default:
1258 		LEAVE(EINVAL);
1259 	}
1260 
1261 	/* Take care of synchronous response, if any. */
1262 quit:
1263 	CTR2(KTR_NET, "%20s: returning %d", __func__, error);
1264 	NG_RESPOND_MSG(error, node, item, resp);
1265 	/* Free the message and return. */
1266 	NG_FREE_MSG(msg);
1267 	return(error);
1268 }
1269 
1270 /*
1271  * Start a client into the first state. A separate function because
1272  * it can be needed if the negotiation times out.
1273  */
1274 static void
1275 pppoe_start(sessp sp)
1276 {
1277 	hook_p	hook = sp->hook;
1278 	node_p	node = NG_HOOK_NODE(hook);
1279 	priv_p	privp = NG_NODE_PRIVATE(node);
1280 	negp	neg = sp->neg;
1281 	struct  mbuf *m0;
1282 	int	error;
1283 
1284 	/*
1285 	 * Kick the state machine into starting up.
1286 	 */
1287 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1288 	sp->state = PPPOE_SINIT;
1289 	/*
1290 	 * Reset the packet header to broadcast. Since we are
1291 	 * in a client mode use configured ethertype.
1292 	 */
1293 	memcpy((void *)&neg->pkt->pkt_header.eh, &privp->eh,
1294 	    sizeof(struct ether_header));
1295 	neg->pkt->pkt_header.ph.code = PADI_CODE;
1296 	init_tags(sp);
1297 	insert_tag(sp, &neg->host_uniq.hdr);
1298 	insert_tag(sp, &neg->service.hdr);
1299 	if (privp->max_payload.data != 0)
1300 		insert_tag(sp, &privp->max_payload.hdr);
1301 	make_packet(sp);
1302 	/*
1303 	 * Send packet and prepare to retransmit it after timeout.
1304 	 */
1305 	ng_callout(&neg->handle, node, hook, PPPOE_INITIAL_TIMEOUT * hz,
1306 	    pppoe_ticker, NULL, 0);
1307 	neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1308 	m0 = m_copypacket(neg->m, M_NOWAIT);
1309 	NG_SEND_DATA_ONLY(error, privp->ethernet_hook, m0);
1310 }
1311 
1312 static int
1313 send_acname(sessp sp, const struct pppoe_tag *tag)
1314 {
1315 	int error, tlen;
1316 	struct ng_mesg *msg;
1317 	struct ngpppoe_sts *sts;
1318 
1319 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1320 
1321 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_ACNAME,
1322 	    sizeof(struct ngpppoe_sts), M_NOWAIT);
1323 	if (msg == NULL)
1324 		return (ENOMEM);
1325 
1326 	sts = (struct ngpppoe_sts *)msg->data;
1327 	tlen = min(NG_HOOKSIZ - 1, ntohs(tag->tag_len));
1328 	strncpy(sts->hook, (const char *)(tag + 1), tlen);
1329 	sts->hook[tlen] = '\0';
1330 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1331 
1332 	return (error);
1333 }
1334 
1335 static int
1336 send_sessionid(sessp sp)
1337 {
1338 	int error;
1339 	struct ng_mesg *msg;
1340 
1341 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1342 
1343 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SESSIONID,
1344 	    sizeof(uint16_t), M_NOWAIT);
1345 	if (msg == NULL)
1346 		return (ENOMEM);
1347 
1348 	*(uint16_t *)msg->data = sp->Session_ID;
1349 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1350 
1351 	return (error);
1352 }
1353 
1354 static int
1355 send_maxp(sessp sp, const struct pppoe_tag *tag)
1356 {
1357 	int error;
1358 	struct ng_mesg *msg;
1359 	struct ngpppoe_maxp *maxp;
1360 
1361 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1362 
1363 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SETMAXP,
1364 	    sizeof(struct ngpppoe_maxp), M_NOWAIT);
1365 	if (msg == NULL)
1366 		return (ENOMEM);
1367 
1368 	maxp = (struct ngpppoe_maxp *)msg->data;
1369 	strncpy(maxp->hook, NG_HOOK_NAME(sp->hook), NG_HOOKSIZ);
1370 	maxp->data = ntohs(((const struct maxptag *)tag)->data);
1371 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1372 
1373 	return (error);
1374 }
1375 
1376 static int
1377 send_hurl(sessp sp, const struct pppoe_tag *tag)
1378 {
1379 	int error, tlen;
1380 	struct ng_mesg *msg;
1381 	struct ngpppoe_padm *padm;
1382 
1383 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1384 
1385 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_HURL,
1386 	    sizeof(struct ngpppoe_padm), M_NOWAIT);
1387 	if (msg == NULL)
1388 		return (ENOMEM);
1389 
1390 	padm = (struct ngpppoe_padm *)msg->data;
1391 	tlen = min(PPPOE_PADM_VALUE_SIZE - 1, ntohs(tag->tag_len));
1392 	strncpy(padm->msg, (const char *)(tag + 1), tlen);
1393 	padm->msg[tlen] = '\0';
1394 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1395 
1396 	return (error);
1397 }
1398 
1399 static int
1400 send_motm(sessp sp, const struct pppoe_tag *tag)
1401 {
1402 	int error, tlen;
1403 	struct ng_mesg *msg;
1404 	struct ngpppoe_padm *padm;
1405 
1406 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1407 
1408 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_MOTM,
1409 	    sizeof(struct ngpppoe_padm), M_NOWAIT);
1410 	if (msg == NULL)
1411 		return (ENOMEM);
1412 
1413 	padm = (struct ngpppoe_padm *)msg->data;
1414 	tlen = min(PPPOE_PADM_VALUE_SIZE - 1, ntohs(tag->tag_len));
1415 	strncpy(padm->msg, (const char *)(tag + 1), tlen);
1416 	padm->msg[tlen] = '\0';
1417 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1418 
1419 	return (error);
1420 }
1421 
1422 /*
1423  * Receive data from session hook and do something with it.
1424  */
1425 static int
1426 ng_pppoe_rcvdata(hook_p hook, item_p item)
1427 {
1428 	node_p			node = NG_HOOK_NODE(hook);
1429 	const priv_p		privp = NG_NODE_PRIVATE(node);
1430 	sessp			sp = NG_HOOK_PRIVATE(hook);
1431 	struct pppoe_full_hdr	*wh;
1432 	struct mbuf		*m;
1433 	int			error;
1434 
1435 	CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1436 	    __func__, node->nd_ID, node, item, hook->hk_name, hook);
1437 
1438 	NGI_GET_M(item, m);
1439 	switch (sp->state) {
1440 	case	PPPOE_NEWCONNECTED:
1441 	case	PPPOE_CONNECTED: {
1442 		/*
1443 		 * Remove PPP address and control fields, if any.
1444 		 * For example, ng_ppp(4) always sends LCP packets
1445 		 * with address and control fields as required by
1446 		 * generic PPP. PPPoE is an exception to the rule.
1447 		 */
1448 		if (m->m_pkthdr.len >= 2) {
1449 			if (m->m_len < 2 && !(m = m_pullup(m, 2)))
1450 				LEAVE(ENOBUFS);
1451 			if (mtod(m, u_char *)[0] == 0xff &&
1452 			    mtod(m, u_char *)[1] == 0x03)
1453 				m_adj(m, 2);
1454 		}
1455 
1456 		if (V_ng_pppoe_lcp_pcp && m->m_pkthdr.len >= 2 &&
1457 		    m->m_len >= 2 && (m = m_pullup(m, 2)) &&
1458 		    mtod(m, uint16_t *)[0] == htons(PROT_LCP))
1459 			EVL_APPLY_PRI(m, (uint8_t)(V_ng_pppoe_lcp_pcp & 0x7));
1460 
1461 		/*
1462 		 * Bang in a pre-made header, and set the length up
1463 		 * to be correct. Then send it to the ethernet driver.
1464 		 */
1465 		M_PREPEND(m, sizeof(*wh), M_NOWAIT);
1466 		if (m == NULL)
1467 			LEAVE(ENOBUFS);
1468 
1469 		wh = mtod(m, struct pppoe_full_hdr *);
1470 		bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1471 		wh->ph.length = htons(m->m_pkthdr.len - sizeof(*wh));
1472 		NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m);
1473 		privp->packets_out++;
1474 		break;
1475 		}
1476 	case	PPPOE_PRIMED: {
1477 		struct {
1478 			struct pppoe_tag hdr;
1479 			union	uniq	data;
1480 		} __packed 	uniqtag;
1481 		const struct pppoe_tag	*tag;
1482 		struct mbuf 	*m0;
1483 		const struct pppoe_hdr	*ph;
1484 		negp		neg = sp->neg;
1485 		uint8_t		code;
1486 
1487 		/*
1488 		 * A PADI packet is being returned by the application
1489 		 * that has set up this hook. This indicates that it
1490 		 * wants us to offer service.
1491 		 */
1492 		if (m->m_len < sizeof(*wh)) {
1493 			m = m_pullup(m, sizeof(*wh));
1494 			if (m == NULL)
1495 				LEAVE(ENOBUFS);
1496 		}
1497 		wh = mtod(m, struct pppoe_full_hdr *);
1498 		ph = &wh->ph;
1499 		code = wh->ph.code;
1500 		/* Use peers mode in session. */
1501 		neg->pkt->pkt_header.eh.ether_type = wh->eh.ether_type;
1502 		if (code != PADI_CODE)
1503 			LEAVE(EINVAL);
1504 		ng_uncallout(&neg->handle, node);
1505 
1506 		/*
1507 		 * This is the first time we hear
1508 		 * from the client, so note it's
1509 		 * unicast address, replacing the
1510 		 * broadcast address.
1511 		 */
1512 		bcopy(wh->eh.ether_shost,
1513 			neg->pkt->pkt_header.eh.ether_dhost,
1514 			ETHER_ADDR_LEN);
1515 		sp->state = PPPOE_SOFFER;
1516 		neg->timeout = 0;
1517 		neg->pkt->pkt_header.ph.code = PADO_CODE;
1518 
1519 		/*
1520 		 * Start working out the tags to respond with.
1521 		 */
1522 		uniqtag.hdr.tag_type = PTT_AC_COOKIE;
1523 		uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(sp));
1524 		uniqtag.data.pointer = sp;
1525 		init_tags(sp);
1526 		insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1527 		if ((tag = get_tag(ph, PTT_SRV_NAME)))
1528 			insert_tag(sp, tag);	  /* return service */
1529 		/*
1530 		 * If we have a NULL service request
1531 		 * and have an extra service defined in this hook,
1532 		 * then also add a tag for the extra service.
1533 		 * XXX this is a hack. eventually we should be able
1534 		 * to support advertising many services, not just one
1535 		 */
1536 		if (((tag == NULL) || (tag->tag_len == 0)) &&
1537 		    (neg->service.hdr.tag_len != 0)) {
1538 			insert_tag(sp, &neg->service.hdr); /* SERVICE */
1539 		}
1540 		if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1541 			insert_tag(sp, tag); /* returned hostunique */
1542 		insert_tag(sp, &uniqtag.hdr);
1543 		scan_tags(sp, ph);
1544 		make_packet(sp);
1545 		/*
1546 		 * Send the offer but if they don't respond
1547 		 * in PPPOE_OFFER_TIMEOUT seconds, forget about it.
1548 		 */
1549 		ng_callout(&neg->handle, node, hook, PPPOE_OFFER_TIMEOUT * hz,
1550 		    pppoe_ticker, NULL, 0);
1551 		m0 = m_copypacket(sp->neg->m, M_NOWAIT);
1552 		NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1553 		privp->packets_out++;
1554 		break;
1555 		}
1556 
1557 	/*
1558 	 * Packets coming from the hook make no sense
1559 	 * to sessions in the rest of states. Throw them away.
1560 	 */
1561 	default:
1562 		LEAVE(ENETUNREACH);
1563 	}
1564 quit:
1565 	if (item)
1566 		NG_FREE_ITEM(item);
1567 	NG_FREE_M(m);
1568 	return (error);
1569 }
1570 
1571 /*
1572  * Receive data from ether and do something with it.
1573  */
1574 static int
1575 ng_pppoe_rcvdata_ether(hook_p hook, item_p item)
1576 {
1577 	node_p			node = NG_HOOK_NODE(hook);
1578 	const priv_p		privp = NG_NODE_PRIVATE(node);
1579 	sessp			sp;
1580 	const struct pppoe_tag	*utag = NULL, *tag = NULL;
1581 	const struct pppoe_tag	sntag = { PTT_SRV_NAME, 0 };
1582 	const struct pppoe_full_hdr *wh;
1583 	const struct pppoe_hdr	*ph;
1584 	negp			neg = NULL;
1585 	struct mbuf		*m;
1586 	hook_p 			sendhook;
1587 	int			error = 0;
1588 	uint16_t		length;
1589 	uint8_t			code;
1590 	struct	mbuf 		*m0;
1591 
1592 	CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1593 	    __func__, node->nd_ID, node, item, hook->hk_name, hook);
1594 
1595 	NGI_GET_M(item, m);
1596 	/*
1597 	 * Dig out various fields from the packet.
1598 	 * Use them to decide where to send it.
1599 	 */
1600 	privp->packets_in++;
1601 	if( m->m_len < sizeof(*wh)) {
1602 		m = m_pullup(m, sizeof(*wh)); /* Checks length */
1603 		if (m == NULL) {
1604 			log(LOG_NOTICE, "ng_pppoe[%x]: couldn't "
1605 			    "m_pullup(wh)\n", node->nd_ID);
1606 			LEAVE(ENOBUFS);
1607 		}
1608 	}
1609 	wh = mtod(m, struct pppoe_full_hdr *);
1610 	length = ntohs(wh->ph.length);
1611 	switch(wh->eh.ether_type) {
1612 	case	ETHERTYPE_PPPOE_3COM_DISC: /* fall through */
1613 	case	ETHERTYPE_PPPOE_DISC:
1614 		/*
1615 		 * We need to try to make sure that the tag area
1616 		 * is contiguous, or we could wander off the end
1617 		 * of a buffer and make a mess.
1618 		 * (Linux wouldn't have this problem).
1619 		 */
1620 		if (m->m_pkthdr.len <= MHLEN) {
1621 			if( m->m_len < m->m_pkthdr.len) {
1622 				m = m_pullup(m, m->m_pkthdr.len);
1623 				if (m == NULL) {
1624 					log(LOG_NOTICE, "ng_pppoe[%x]: "
1625 					    "couldn't m_pullup(pkthdr)\n",
1626 					    node->nd_ID);
1627 					LEAVE(ENOBUFS);
1628 				}
1629 			}
1630 		}
1631 		if (m->m_len != m->m_pkthdr.len) {
1632 			/*
1633 			 * It's not all in one piece.
1634 			 * We need to do extra work.
1635 			 * Put it into a cluster.
1636 			 */
1637 			struct mbuf *n;
1638 			n = m_dup(m, M_NOWAIT);
1639 			m_freem(m);
1640 			m = n;
1641 			if (m) {
1642 				/* just check we got a cluster */
1643 				if (m->m_len != m->m_pkthdr.len) {
1644 					m_freem(m);
1645 					m = NULL;
1646 				}
1647 			}
1648 			if (m == NULL) {
1649 				log(LOG_NOTICE, "ng_pppoe[%x]: packet "
1650 				    "fragmented\n", node->nd_ID);
1651 				LEAVE(EMSGSIZE);
1652 			}
1653 		}
1654 		wh = mtod(m, struct pppoe_full_hdr *);
1655 		length = ntohs(wh->ph.length);
1656 		ph = &wh->ph;
1657 		code = wh->ph.code;
1658 
1659 		switch(code) {
1660 		case	PADI_CODE:
1661 			/*
1662 			 * We are a server:
1663 			 * Look for a hook with the required service and send
1664 			 * the ENTIRE packet up there. It should come back to
1665 			 * a new hook in PRIMED state. Look there for further
1666 			 * processing.
1667 			 */
1668 			tag = get_tag(ph, PTT_SRV_NAME);
1669 			if (tag == NULL)
1670 				tag = &sntag;
1671 
1672 			/*
1673 			 * First, try to match Service-Name against our
1674 			 * listening hooks. If no success and we are in D-Link
1675 			 * compat mode and Service-Name is empty, then we
1676 			 * broadcast the PADI to all listening hooks.
1677 			 */
1678 			sendhook = pppoe_match_svc(node, tag);
1679 			if (sendhook != NULL)
1680 				NG_FWD_NEW_DATA(error, item, sendhook, m);
1681 			else if (privp->flags & COMPAT_DLINK &&
1682 				 ntohs(tag->tag_len) == 0)
1683 				error = pppoe_broadcast_padi(node, m);
1684 			else
1685 				error = ENETUNREACH;
1686 			break;
1687 		case	PADO_CODE:
1688 			/*
1689 			 * We are a client:
1690 			 * Use the host_uniq tag to find the hook this is in
1691 			 * response to. Received #2, now send #3
1692 			 * For now simply accept the first we receive.
1693 			 */
1694 			utag = get_tag(ph, PTT_HOST_UNIQ);
1695 			if (utag == NULL) {
1696 				log(LOG_NOTICE, "ng_pppoe[%x]: no host "
1697 				    "unique field\n", node->nd_ID);
1698 				LEAVE(ENETUNREACH);
1699 			}
1700 
1701 			sendhook = pppoe_finduniq(node, utag);
1702 			if (sendhook == NULL) {
1703 				log(LOG_NOTICE, "ng_pppoe[%x]: no "
1704 				    "matching session\n", node->nd_ID);
1705 				LEAVE(ENETUNREACH);
1706 			}
1707 
1708 			/*
1709 			 * Check the session is in the right state.
1710 			 * It needs to be in PPPOE_SINIT.
1711 			 */
1712 			sp = NG_HOOK_PRIVATE(sendhook);
1713 			if (sp->state == PPPOE_SREQ ||
1714 			    sp->state == PPPOE_CONNECTED) {
1715 				break;	/* Multiple PADO is OK. */
1716 			}
1717 			if (sp->state != PPPOE_SINIT) {
1718 				log(LOG_NOTICE, "ng_pppoe[%x]: session "
1719 				    "in wrong state\n", node->nd_ID);
1720 				LEAVE(ENETUNREACH);
1721 			}
1722 			neg = sp->neg;
1723 			/* If requested specific AC-name, check it. */
1724 			if (neg->ac_name_len) {
1725 				tag = get_tag(ph, PTT_AC_NAME);
1726 				if (!tag) {
1727 					/* No PTT_AC_NAME in PADO */
1728 					break;
1729 				}
1730 				if (neg->ac_name_len != htons(tag->tag_len) ||
1731 				    strncmp(neg->ac_name.data,
1732 				    (const char *)(tag + 1),
1733 				    neg->ac_name_len) != 0) {
1734 					break;
1735 				}
1736 			}
1737 			sp->state = PPPOE_SREQ;
1738 			ng_uncallout(&neg->handle, node);
1739 
1740 			/*
1741 			 * This is the first time we hear
1742 			 * from the server, so note it's
1743 			 * unicast address, replacing the
1744 			 * broadcast address .
1745 			 */
1746 			bcopy(wh->eh.ether_shost,
1747 				neg->pkt->pkt_header.eh.ether_dhost,
1748 				ETHER_ADDR_LEN);
1749 			neg->timeout = 0;
1750 			neg->pkt->pkt_header.ph.code = PADR_CODE;
1751 			init_tags(sp);
1752 			insert_tag(sp, utag);      	/* Host Unique */
1753 			if ((tag = get_tag(ph, PTT_AC_COOKIE)))
1754 				insert_tag(sp, tag); 	/* return cookie */
1755 			if ((tag = get_tag(ph, PTT_AC_NAME))) {
1756 				insert_tag(sp, tag); 	/* return it */
1757 				send_acname(sp, tag);
1758 			}
1759 			if ((tag = get_tag(ph, PTT_MAX_PAYL)) &&
1760 			    (privp->max_payload.data != 0))
1761 				insert_tag(sp, tag);	/* return it */
1762 			insert_tag(sp, &neg->service.hdr); /* Service */
1763 			scan_tags(sp, ph);
1764 			make_packet(sp);
1765 			sp->state = PPPOE_SREQ;
1766 			ng_callout(&neg->handle, node, sp->hook,
1767 			    PPPOE_INITIAL_TIMEOUT * hz,
1768 			    pppoe_ticker, NULL, 0);
1769 			neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1770 			m0 = m_copypacket(neg->m, M_NOWAIT);
1771 			NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1772 			break;
1773 		case	PADR_CODE:
1774 			/*
1775 			 * We are a server:
1776 			 * Use the ac_cookie tag to find the
1777 			 * hook this is in response to.
1778 			 */
1779 			utag = get_tag(ph, PTT_AC_COOKIE);
1780 			if ((utag == NULL) ||
1781 			    (ntohs(utag->tag_len) != sizeof(sp))) {
1782 				LEAVE(ENETUNREACH);
1783 			}
1784 
1785 			sendhook = pppoe_findcookie(node, utag);
1786 			if (sendhook == NULL)
1787 				LEAVE(ENETUNREACH);
1788 
1789 			/*
1790 			 * Check the session is in the right state.
1791 			 * It needs to be in PPPOE_SOFFER or PPPOE_NEWCONNECTED.
1792 			 * If the latter, then this is a retry by the client,
1793 			 * so be nice, and resend.
1794 			 */
1795 			sp = NG_HOOK_PRIVATE(sendhook);
1796 			if (sp->state == PPPOE_NEWCONNECTED) {
1797 				/*
1798 				 * Whoa! drop back to resend that PADS packet.
1799 				 * We should still have a copy of it.
1800 				 */
1801 				sp->state = PPPOE_SOFFER;
1802 			} else if (sp->state != PPPOE_SOFFER)
1803 				LEAVE (ENETUNREACH);
1804 			neg = sp->neg;
1805 			ng_uncallout(&neg->handle, node);
1806 			neg->pkt->pkt_header.ph.code = PADS_CODE;
1807 			if (sp->Session_ID == 0) {
1808 				neg->pkt->pkt_header.ph.sid =
1809 				    htons(pppoe_getnewsession(sp));
1810 			}
1811 			send_sessionid(sp);
1812 			neg->timeout = 0;
1813 			/*
1814 			 * start working out the tags to respond with.
1815 			 */
1816 			init_tags(sp);
1817 			insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1818 			if ((tag = get_tag(ph, PTT_SRV_NAME)))
1819 				insert_tag(sp, tag);/* return service */
1820 			if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1821 				insert_tag(sp, tag); /* return it */
1822 			insert_tag(sp, utag);	/* ac_cookie */
1823 			scan_tags(sp, ph);
1824 			make_packet(sp);
1825 			sp->state = PPPOE_NEWCONNECTED;
1826 
1827 			/* Send the PADS without a timeout - we're now connected. */
1828 			m0 = m_copypacket(sp->neg->m, M_NOWAIT);
1829 			NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1830 
1831 			/*
1832 			 * Having sent the last Negotiation header,
1833 			 * Set up the stored packet header to be correct for
1834 			 * the actual session. But keep the negotialtion stuff
1835 			 * around in case we need to resend this last packet.
1836 			 * We'll discard it when we move from NEWCONNECTED
1837 			 * to CONNECTED
1838 			 */
1839 			sp->pkt_hdr = neg->pkt->pkt_header;
1840 			/* Configure ethertype depending on what
1841 			 * ethertype was used at discovery phase */
1842 			if (sp->pkt_hdr.eh.ether_type ==
1843 			    ETHERTYPE_PPPOE_3COM_DISC)
1844 				sp->pkt_hdr.eh.ether_type
1845 					= ETHERTYPE_PPPOE_3COM_SESS;
1846 			else
1847 				sp->pkt_hdr.eh.ether_type
1848 					= ETHERTYPE_PPPOE_SESS;
1849 			sp->pkt_hdr.ph.code = 0;
1850 			pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1851 			break;
1852 		case	PADS_CODE:
1853 			/*
1854 			 * We are a client:
1855 			 * Use the host_uniq tag to find the hook this is in
1856 			 * response to. Take the session ID and store it away.
1857 			 * Also make sure the pre-made header is correct and
1858 			 * set us into Session mode.
1859 			 */
1860 			utag = get_tag(ph, PTT_HOST_UNIQ);
1861 			if (utag == NULL) {
1862 				LEAVE (ENETUNREACH);
1863 			}
1864 			sendhook = pppoe_finduniq(node, utag);
1865 			if (sendhook == NULL)
1866 				LEAVE(ENETUNREACH);
1867 
1868 			/*
1869 			 * Check the session is in the right state.
1870 			 * It needs to be in PPPOE_SREQ.
1871 			 */
1872 			sp = NG_HOOK_PRIVATE(sendhook);
1873 			if (sp->state != PPPOE_SREQ)
1874 				LEAVE(ENETUNREACH);
1875 			neg = sp->neg;
1876 			ng_uncallout(&neg->handle, node);
1877 			neg->pkt->pkt_header.ph.sid = wh->ph.sid;
1878 			sp->Session_ID = ntohs(wh->ph.sid);
1879 			pppoe_addsession(sp);
1880 			send_sessionid(sp);
1881 			neg->timeout = 0;
1882 			sp->state = PPPOE_CONNECTED;
1883 			/*
1884 			 * Now we have gone to Connected mode,
1885 			 * Free all resources needed for negotiation.
1886 			 * Keep a copy of the header we will be using.
1887 			 */
1888 			sp->pkt_hdr = neg->pkt->pkt_header;
1889 			if (privp->flags & COMPAT_3COM)
1890 				sp->pkt_hdr.eh.ether_type
1891 					= ETHERTYPE_PPPOE_3COM_SESS;
1892 			else
1893 				sp->pkt_hdr.eh.ether_type
1894 					= ETHERTYPE_PPPOE_SESS;
1895 			sp->pkt_hdr.ph.code = 0;
1896 			m_freem(neg->m);
1897 			free(sp->neg, M_NETGRAPH_PPPOE);
1898 			sp->neg = NULL;
1899 			if ((tag = get_tag(ph, PTT_MAX_PAYL)) &&
1900 			    (privp->max_payload.data != 0))
1901 				send_maxp(sp, tag);
1902 			pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1903 			break;
1904 		case	PADT_CODE:
1905 			/*
1906 			 * Find matching peer/session combination.
1907 			 */
1908 			sp = pppoe_findsession(privp, wh);
1909 			if (sp == NULL)
1910 				LEAVE(ENETUNREACH);
1911 			/* Disconnect that hook. */
1912 			ng_rmhook_self(sp->hook);
1913 			break;
1914 		case	PADM_CODE:
1915 			/*
1916 			 * We are a client:
1917 			 * find matching peer/session combination.
1918 			 */
1919 			sp = pppoe_findsession(privp, wh);
1920 			if (sp == NULL)
1921 				LEAVE (ENETUNREACH);
1922 			if ((tag = get_tag(ph, PTT_HURL)))
1923 				send_hurl(sp, tag);
1924 			if ((tag = get_tag(ph, PTT_MOTM)))
1925 				send_motm(sp, tag);
1926 			break;
1927 		default:
1928 			LEAVE(EPFNOSUPPORT);
1929 		}
1930 		break;
1931 	case	ETHERTYPE_PPPOE_3COM_SESS:
1932 	case	ETHERTYPE_PPPOE_SESS:
1933 		/*
1934 		 * Find matching peer/session combination.
1935 		 */
1936 		sp = pppoe_findsession(privp, wh);
1937 		if (sp == NULL)
1938 			LEAVE (ENETUNREACH);
1939 		m_adj(m, sizeof(*wh));
1940 
1941 		/* If packet too short, dump it. */
1942 		if (m->m_pkthdr.len < length)
1943 			LEAVE(EMSGSIZE);
1944 		/* Also need to trim excess at the end */
1945 		if (m->m_pkthdr.len > length) {
1946 			m_adj(m, -((int)(m->m_pkthdr.len - length)));
1947 		}
1948 		if ( sp->state != PPPOE_CONNECTED) {
1949 			if (sp->state == PPPOE_NEWCONNECTED) {
1950 				sp->state = PPPOE_CONNECTED;
1951 				/*
1952 				 * Now we have gone to Connected mode,
1953 				 * Free all resources needed for negotiation.
1954 				 * Be paranoid about whether there may be
1955 				 * a timeout.
1956 				 */
1957 				m_freem(sp->neg->m);
1958 				ng_uncallout(&sp->neg->handle, node);
1959 				free(sp->neg, M_NETGRAPH_PPPOE);
1960 				sp->neg = NULL;
1961 			} else {
1962 				LEAVE (ENETUNREACH);
1963 			}
1964 		}
1965 		NG_FWD_NEW_DATA(error, item, sp->hook, m);
1966 		break;
1967 	default:
1968 		LEAVE(EPFNOSUPPORT);
1969 	}
1970 quit:
1971 	if (item)
1972 		NG_FREE_ITEM(item);
1973 	NG_FREE_M(m);
1974 	return (error);
1975 }
1976 
1977 /*
1978  * Receive data from debug hook and bypass it to ether.
1979  */
1980 static int
1981 ng_pppoe_rcvdata_debug(hook_p hook, item_p item)
1982 {
1983 	node_p		node = NG_HOOK_NODE(hook);
1984 	const priv_p	privp = NG_NODE_PRIVATE(node);
1985 	int		error;
1986 
1987 	CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1988 	    __func__, node->nd_ID, node, item, hook->hk_name, hook);
1989 
1990 	NG_FWD_ITEM_HOOK(error, item, privp->ethernet_hook);
1991 	privp->packets_out++;
1992 	return (error);
1993 }
1994 
1995 /*
1996  * Do local shutdown processing..
1997  * If we are a persistent device, we might refuse to go away, and
1998  * we'd only remove our links and reset ourself.
1999  */
2000 static int
2001 ng_pppoe_shutdown(node_p node)
2002 {
2003 	const priv_p privp = NG_NODE_PRIVATE(node);
2004 	int	i;
2005 
2006 	for (i = 0; i < SESSHASHSIZE; i++)
2007 	    mtx_destroy(&privp->sesshash[i].mtx);
2008 	NG_NODE_SET_PRIVATE(node, NULL);
2009 	NG_NODE_UNREF(privp->node);
2010 	free(privp, M_NETGRAPH_PPPOE);
2011 	return (0);
2012 }
2013 
2014 /*
2015  * Hook disconnection
2016  *
2017  * Clean up all dangling links and information about the session/hook.
2018  * For this type, removal of the last link destroys the node.
2019  */
2020 static int
2021 ng_pppoe_disconnect(hook_p hook)
2022 {
2023 	node_p node = NG_HOOK_NODE(hook);
2024 	priv_p privp = NG_NODE_PRIVATE(node);
2025 	sessp	sp;
2026 
2027 	if (hook == privp->debug_hook) {
2028 		privp->debug_hook = NULL;
2029 	} else if (hook == privp->ethernet_hook) {
2030 		privp->ethernet_hook = NULL;
2031 		if (NG_NODE_IS_VALID(node))
2032 			ng_rmnode_self(node);
2033 	} else {
2034 		sp = NG_HOOK_PRIVATE(hook);
2035 		if (sp->state != PPPOE_SNONE ) {
2036 			pppoe_send_event(sp, NGM_PPPOE_CLOSE);
2037 		}
2038 		/*
2039 		 * According to the spec, if we are connected,
2040 		 * we should send a DISC packet if we are shutting down
2041 		 * a session.
2042 		 */
2043 		if ((privp->ethernet_hook)
2044 		&& ((sp->state == PPPOE_CONNECTED)
2045 		 || (sp->state == PPPOE_NEWCONNECTED))) {
2046 			struct mbuf *m;
2047 
2048 			/* Generate a packet of that type. */
2049 			m = m_gethdr(M_NOWAIT, MT_DATA);
2050 			if (m == NULL)
2051 				log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
2052 				    "mbufs\n", node->nd_ID);
2053 			else {
2054 				struct epoch_tracker et;
2055 				struct pppoe_full_hdr *wh;
2056 				struct pppoe_tag *tag;
2057 				int	msglen = strlen(SIGNOFF);
2058 				int	error = 0;
2059 
2060 				wh = mtod(m, struct pppoe_full_hdr *);
2061 				bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
2062 
2063 				/* Revert the stored header to DISC/PADT mode. */
2064 				wh->ph.code = PADT_CODE;
2065 				/*
2066 				 * Configure ethertype depending on what
2067 				 * was used during sessions stage.
2068 				 */
2069 				if (wh->eh.ether_type ==
2070 				    ETHERTYPE_PPPOE_3COM_SESS)
2071 					wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
2072 				else
2073 					wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
2074 				/*
2075 				 * Add a General error message and adjust
2076 				 * sizes.
2077 				 */
2078 				tag = (void *)(&wh->ph + 1);
2079 				tag->tag_type = PTT_GEN_ERR;
2080 				tag->tag_len = htons((u_int16_t)msglen);
2081 				strncpy((char *)(tag + 1), SIGNOFF, msglen);
2082 				m->m_pkthdr.len = m->m_len = sizeof(*wh) + sizeof(*tag) +
2083 				    msglen;
2084 				wh->ph.length = htons(sizeof(*tag) + msglen);
2085 
2086 				NET_EPOCH_ENTER(et);
2087 				NG_SEND_DATA_ONLY(error,
2088 					privp->ethernet_hook, m);
2089 				NET_EPOCH_EXIT(et);
2090 			}
2091 		}
2092 		if (sp->state == PPPOE_LISTENING)
2093 			LIST_REMOVE(sp, sessions);
2094 		else if (sp->Session_ID)
2095 			pppoe_delsession(sp);
2096 		/*
2097 		 * As long as we have somewhere to store the timeout handle,
2098 		 * we may have a timeout pending.. get rid of it.
2099 		 */
2100 		if (sp->neg) {
2101 			ng_uncallout(&sp->neg->handle, node);
2102 			if (sp->neg->m)
2103 				m_freem(sp->neg->m);
2104 			free(sp->neg, M_NETGRAPH_PPPOE);
2105 		}
2106 		free(sp, M_NETGRAPH_PPPOE);
2107 		NG_HOOK_SET_PRIVATE(hook, NULL);
2108 	}
2109 	if ((NG_NODE_NUMHOOKS(node) == 0) &&
2110 	    (NG_NODE_IS_VALID(node)))
2111 		ng_rmnode_self(node);
2112 	return (0);
2113 }
2114 
2115 /*
2116  * Timeouts come here.
2117  */
2118 static void
2119 pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2)
2120 {
2121 	priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
2122 	sessp	sp = NG_HOOK_PRIVATE(hook);
2123 	negp	neg = sp->neg;
2124 	struct mbuf *m0 = NULL;
2125 	int	error = 0;
2126 
2127 	CTR6(KTR_NET, "%20s: node [%x] (%p) hook \"%s\" (%p) session %d",
2128 	    __func__, node->nd_ID, node, hook->hk_name, hook, sp->Session_ID);
2129 	switch(sp->state) {
2130 		/*
2131 		 * Resend the last packet, using an exponential backoff.
2132 		 * After a period of time, stop growing the backoff,
2133 		 * And either leave it, or revert to the start.
2134 		 */
2135 	case	PPPOE_SINIT:
2136 	case	PPPOE_SREQ:
2137 		/* Timeouts on these produce resends. */
2138 		m0 = m_copypacket(sp->neg->m, M_NOWAIT);
2139 		NG_SEND_DATA_ONLY( error, privp->ethernet_hook, m0);
2140 		ng_callout(&neg->handle, node, hook, neg->timeout * hz,
2141 		    pppoe_ticker, NULL, 0);
2142 		if ((neg->timeout <<= 1) > PPPOE_TIMEOUT_LIMIT) {
2143 			if (sp->state == PPPOE_SREQ) {
2144 				/* Revert to SINIT mode. */
2145 				pppoe_start(sp);
2146 			} else {
2147 				neg->timeout = PPPOE_TIMEOUT_LIMIT;
2148 			}
2149 		}
2150 		break;
2151 	case	PPPOE_PRIMED:
2152 	case	PPPOE_SOFFER:
2153 		/* A timeout on these says "give up" */
2154 		ng_rmhook_self(hook);
2155 		break;
2156 	default:
2157 		/* Timeouts have no meaning in other states. */
2158 		log(LOG_NOTICE, "ng_pppoe[%x]: unexpected timeout\n",
2159 		    node->nd_ID);
2160 	}
2161 }
2162 
2163 /*
2164  * Parse an incoming packet to see if any tags should be copied to the
2165  * output packet. Don't do any tags that have been handled in the main
2166  * state machine.
2167  */
2168 static const struct pppoe_tag*
2169 scan_tags(sessp	sp, const struct pppoe_hdr* ph)
2170 {
2171 	const char *const end = (const char *)next_tag(ph);
2172 	const char *ptn;
2173 	const struct pppoe_tag *pt = (const void *)(ph + 1);
2174 
2175 	/*
2176 	 * Keep processing tags while a tag header will still fit.
2177 	 */
2178 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
2179 
2180 	while((const char*)(pt + 1) <= end) {
2181 		/*
2182 		 * If the tag data would go past the end of the packet, abort.
2183 		 */
2184 		ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
2185 		if(ptn > end)
2186 			return NULL;
2187 
2188 		switch (pt->tag_type) {
2189 		case	PTT_RELAY_SID:
2190 			insert_tag(sp, pt);
2191 			break;
2192 		case	PTT_EOL:
2193 			return NULL;
2194 		case	PTT_SRV_NAME:
2195 		case	PTT_AC_NAME:
2196 		case	PTT_HOST_UNIQ:
2197 		case	PTT_AC_COOKIE:
2198 		case	PTT_VENDOR:
2199 		case	PTT_SRV_ERR:
2200 		case	PTT_SYS_ERR:
2201 		case	PTT_GEN_ERR:
2202 		case	PTT_MAX_PAYL:
2203 		case	PTT_HURL:
2204 		case	PTT_MOTM:
2205 			break;
2206 		}
2207 		pt = (const struct pppoe_tag*)ptn;
2208 	}
2209 	return NULL;
2210 }
2211 
2212 static	int
2213 pppoe_send_event(sessp sp, enum cmd cmdid)
2214 {
2215 	int error;
2216 	struct ng_mesg *msg;
2217 	struct ngpppoe_sts *sts;
2218 
2219 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
2220 
2221 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, cmdid,
2222 			sizeof(struct ngpppoe_sts), M_NOWAIT);
2223 	if (msg == NULL)
2224 		return (ENOMEM);
2225 	sts = (struct ngpppoe_sts *)msg->data;
2226 	strncpy(sts->hook, NG_HOOK_NAME(sp->hook), NG_HOOKSIZ);
2227 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
2228 	return (error);
2229 }
2230