xref: /freebsd/sys/netgraph/ng_pppoe.c (revision 716fd348e01c5f2ba125f878a634a753436c2994)
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/epoch.h>
52 #include <sys/socket.h>
53 #include <sys/sysctl.h>
54 #include <sys/syslog.h>
55 #include <net/ethernet.h>
56 #include <net/if.h>
57 #include <net/if_vlan_var.h>
58 #include <net/vnet.h>
59 
60 #include <netgraph/ng_message.h>
61 #include <netgraph/netgraph.h>
62 #include <netgraph/ng_parse.h>
63 #include <netgraph/ng_pppoe.h>
64 #include <netgraph/ng_ether.h>
65 
66 #ifdef NG_SEPARATE_MALLOC
67 static MALLOC_DEFINE(M_NETGRAPH_PPPOE, "netgraph_pppoe", "netgraph pppoe node");
68 #else
69 #define M_NETGRAPH_PPPOE M_NETGRAPH
70 #endif
71 
72 /* Some PPP protocol numbers we're interested in */
73 #define PROT_LCP		0xc021
74 
75 #define SIGNOFF "session closed"
76 
77 VNET_DEFINE_STATIC(u_int32_t, ng_pppoe_lcp_pcp) = 0;
78 #define V_ng_pppoe_lcp_pcp	VNET(ng_pppoe_lcp_pcp)
79 
80 SYSCTL_NODE(_net_graph, OID_AUTO, pppoe, CTLFLAG_RW, 0, "PPPoE");
81 SYSCTL_UINT(_net_graph_pppoe, OID_AUTO, lcp_pcp,
82 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ng_pppoe_lcp_pcp), 0,
83 	"Set PCP for LCP");
84 
85 /*
86  * This section contains the netgraph method declarations for the
87  * pppoe node. These methods define the netgraph pppoe 'type'.
88  */
89 
90 static ng_constructor_t	ng_pppoe_constructor;
91 static ng_rcvmsg_t	ng_pppoe_rcvmsg;
92 static ng_shutdown_t	ng_pppoe_shutdown;
93 static ng_newhook_t	ng_pppoe_newhook;
94 static ng_connect_t	ng_pppoe_connect;
95 static ng_rcvdata_t	ng_pppoe_rcvdata;
96 static ng_rcvdata_t	ng_pppoe_rcvdata_ether;
97 static ng_rcvdata_t	ng_pppoe_rcvdata_debug;
98 static ng_disconnect_t	ng_pppoe_disconnect;
99 
100 /* Parse type for struct ngpppoe_init_data */
101 static const struct ng_parse_struct_field ngpppoe_init_data_type_fields[]
102 	= NG_PPPOE_INIT_DATA_TYPE_INFO;
103 static const struct ng_parse_type ngpppoe_init_data_state_type = {
104 	&ng_parse_struct_type,
105 	&ngpppoe_init_data_type_fields
106 };
107 
108 /* Parse type for struct ngpppoe_sts */
109 static const struct ng_parse_struct_field ng_pppoe_sts_type_fields[]
110 	= NG_PPPOE_STS_TYPE_INFO;
111 static const struct ng_parse_type ng_pppoe_sts_state_type = {
112 	&ng_parse_struct_type,
113 	&ng_pppoe_sts_type_fields
114 };
115 
116 /* List of commands and how to convert arguments to/from ASCII */
117 static const struct ng_cmdlist ng_pppoe_cmds[] = {
118 	{
119 	  NGM_PPPOE_COOKIE,
120 	  NGM_PPPOE_CONNECT,
121 	  "pppoe_connect",
122 	  &ngpppoe_init_data_state_type,
123 	  NULL
124 	},
125 	{
126 	  NGM_PPPOE_COOKIE,
127 	  NGM_PPPOE_LISTEN,
128 	  "pppoe_listen",
129 	  &ngpppoe_init_data_state_type,
130 	  NULL
131 	},
132 	{
133 	  NGM_PPPOE_COOKIE,
134 	  NGM_PPPOE_OFFER,
135 	  "pppoe_offer",
136 	  &ngpppoe_init_data_state_type,
137 	  NULL
138 	},
139 	{
140 	  NGM_PPPOE_COOKIE,
141 	  NGM_PPPOE_SERVICE,
142 	  "pppoe_service",
143 	  &ngpppoe_init_data_state_type,
144 	  NULL
145 	},
146 	{
147 	  NGM_PPPOE_COOKIE,
148 	  NGM_PPPOE_SUCCESS,
149 	  "pppoe_success",
150 	  &ng_pppoe_sts_state_type,
151 	  NULL
152 	},
153 	{
154 	  NGM_PPPOE_COOKIE,
155 	  NGM_PPPOE_FAIL,
156 	  "pppoe_fail",
157 	  &ng_pppoe_sts_state_type,
158 	  NULL
159 	},
160 	{
161 	  NGM_PPPOE_COOKIE,
162 	  NGM_PPPOE_CLOSE,
163 	  "pppoe_close",
164 	  &ng_pppoe_sts_state_type,
165 	  NULL
166 	},
167 	{
168 	  NGM_PPPOE_COOKIE,
169 	  NGM_PPPOE_SETMODE,
170 	  "pppoe_setmode",
171 	  &ng_parse_string_type,
172 	  NULL
173 	},
174 	{
175 	  NGM_PPPOE_COOKIE,
176 	  NGM_PPPOE_GETMODE,
177 	  "pppoe_getmode",
178 	  NULL,
179 	  &ng_parse_string_type
180 	},
181 	{
182 	  NGM_PPPOE_COOKIE,
183 	  NGM_PPPOE_SETENADDR,
184 	  "setenaddr",
185 	  &ng_parse_enaddr_type,
186 	  NULL
187 	},
188 	{
189 	  NGM_PPPOE_COOKIE,
190 	  NGM_PPPOE_SETMAXP,
191 	  "setmaxp",
192 	  &ng_parse_uint16_type,
193 	  NULL
194 	},
195         {
196 	  NGM_PPPOE_COOKIE,
197 	  NGM_PPPOE_SEND_HURL,
198 	  "send_hurl",
199 	  &ngpppoe_init_data_state_type,
200 	  NULL
201         },
202         {
203 	  NGM_PPPOE_COOKIE,
204 	  NGM_PPPOE_SEND_MOTM,
205 	  "send_motm",
206 	  &ngpppoe_init_data_state_type,
207 	  NULL
208         },
209 	{ 0 }
210 };
211 
212 /* Netgraph node type descriptor */
213 static struct ng_type typestruct = {
214 	.version =	NG_ABI_VERSION,
215 	.name =		NG_PPPOE_NODE_TYPE,
216 	.constructor =	ng_pppoe_constructor,
217 	.rcvmsg =	ng_pppoe_rcvmsg,
218 	.shutdown =	ng_pppoe_shutdown,
219 	.newhook =	ng_pppoe_newhook,
220 	.connect =	ng_pppoe_connect,
221 	.rcvdata =	ng_pppoe_rcvdata,
222 	.disconnect =	ng_pppoe_disconnect,
223 	.cmdlist =	ng_pppoe_cmds,
224 };
225 NETGRAPH_INIT(pppoe, &typestruct);
226 
227 /*
228  * States for the session state machine.
229  * These have no meaning if there is no hook attached yet.
230  */
231 enum state {
232     PPPOE_SNONE=0,	/* [both] Initial state */
233     PPPOE_LISTENING,	/* [Daemon] Listening for discover initiation pkt */
234     PPPOE_SINIT,	/* [Client] Sent discovery initiation */
235     PPPOE_PRIMED,	/* [Server] Awaiting PADI from daemon */
236     PPPOE_SOFFER,	/* [Server] Sent offer message  (got PADI)*/
237     PPPOE_SREQ,		/* [Client] Sent a Request */
238     PPPOE_NEWCONNECTED,	/* [Server] Connection established, No data received */
239     PPPOE_CONNECTED,	/* [Both] Connection established, Data received */
240     PPPOE_DEAD		/* [Both] */
241 };
242 
243 #define NUMTAGS 20 /* number of tags we are set up to work with */
244 
245 /*
246  * Information we store for each hook on each node for negotiating the
247  * session. The mbuf and cluster are freed once negotiation has completed.
248  * The whole negotiation block is then discarded.
249  */
250 
251 struct sess_neg {
252 	struct mbuf 		*m; /* holds cluster with last sent packet */
253 	union	packet		*pkt; /* points within the above cluster */
254 	struct callout		handle;   /* see timeout(9) */
255 	u_int			timeout; /* 0,1,2,4,8,16 etc. seconds */
256 	u_int			numtags;
257 	const struct pppoe_tag	*tags[NUMTAGS];
258 	u_int			service_len;
259 	u_int			ac_name_len;
260 	u_int			host_uniq_len;
261 
262 	struct datatag		service;
263 	struct datatag		ac_name;
264 	struct datatag		host_uniq;
265 };
266 typedef struct sess_neg *negp;
267 
268 /*
269  * Session information that is needed after connection.
270  */
271 struct sess_con {
272 	hook_p  		hook;
273 	uint16_t		Session_ID;
274 	enum state		state;
275 	ng_ID_t			creator;	/* who to notify */
276 	struct pppoe_full_hdr	pkt_hdr;	/* used when connected */
277 	negp			neg;		/* used when negotiating */
278 	LIST_ENTRY(sess_con)	sessions;
279 };
280 typedef struct sess_con *sessp;
281 
282 #define SESSHASHSIZE	0x0100
283 #define SESSHASH(x)	(((x) ^ ((x) >> 8)) & (SESSHASHSIZE - 1))
284 
285 struct sess_hash_entry {
286 	struct mtx	mtx;
287 	LIST_HEAD(hhead, sess_con) head;
288 };
289 
290 /*
291  * Information we store for each node
292  */
293 struct PPPoE {
294 	node_p		node;		/* back pointer to node */
295 	hook_p  	ethernet_hook;
296 	hook_p  	debug_hook;
297 	u_int   	packets_in;	/* packets in from ethernet */
298 	u_int   	packets_out;	/* packets out towards ethernet */
299 	uint32_t	flags;
300 #define	COMPAT_3COM	0x00000001
301 #define	COMPAT_DLINK	0x00000002
302 	struct ether_header	eh;
303 	LIST_HEAD(, sess_con) listeners;
304 	struct sess_hash_entry	sesshash[SESSHASHSIZE];
305 	struct maxptag	max_payload;	/* PPP-Max-Payload (RFC4638) */
306 };
307 typedef struct PPPoE *priv_p;
308 
309 union uniq {
310 	char bytes[sizeof(void *)];
311 	void *pointer;
312 };
313 
314 #define	LEAVE(x) do { error = x; goto quit; } while(0)
315 static void	pppoe_start(sessp sp);
316 static void	pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2);
317 static const	struct pppoe_tag *scan_tags(sessp sp,
318 			const struct pppoe_hdr* ph);
319 static	int	pppoe_send_event(sessp sp, enum cmd cmdid);
320 
321 /*************************************************************************
322  * Some basic utilities  from the Linux version with author's permission.*
323  * Author:	Michal Ostrowski <mostrows@styx.uwaterloo.ca>		 *
324  ************************************************************************/
325 
326 /*
327  * Return the location where the next tag can be put
328  */
329 static __inline const struct pppoe_tag*
330 next_tag(const struct pppoe_hdr* ph)
331 {
332 	return (const struct pppoe_tag*)(((const char*)(ph + 1))
333 	    + ntohs(ph->length));
334 }
335 
336 /*
337  * Look for a tag of a specific type.
338  * Don't trust any length the other end says,
339  * but assume we already sanity checked ph->length.
340  */
341 static const struct pppoe_tag*
342 get_tag(const struct pppoe_hdr* ph, uint16_t idx)
343 {
344 	const char *const end = (const char *)next_tag(ph);
345 	const struct pppoe_tag *pt = (const void *)(ph + 1);
346 	const char *ptn;
347 
348 	/*
349 	 * Keep processing tags while a tag header will still fit.
350 	 */
351 	while((const char*)(pt + 1) <= end) {
352 		/*
353 		 * If the tag data would go past the end of the packet, abort.
354 		 */
355 		ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
356 		if (ptn > end) {
357 			CTR2(KTR_NET, "%20s: invalid length for tag %d",
358 			    __func__, idx);
359 			return (NULL);
360 		}
361 		if (pt->tag_type == idx) {
362 			CTR2(KTR_NET, "%20s: found tag %d", __func__, idx);
363 			return (pt);
364 		}
365 
366 		pt = (const struct pppoe_tag*)ptn;
367 	}
368 
369 	CTR2(KTR_NET, "%20s: not found tag %d", __func__, idx);
370 	return (NULL);
371 }
372 
373 /**************************************************************************
374  * Inlines to initialise or add tags to a session's tag list.
375  **************************************************************************/
376 /*
377  * Initialise the session's tag list.
378  */
379 static void
380 init_tags(sessp sp)
381 {
382 	KASSERT(sp->neg != NULL, ("%s: no neg", __func__));
383 	sp->neg->numtags = 0;
384 }
385 
386 static void
387 insert_tag(sessp sp, const struct pppoe_tag *tp)
388 {
389 	negp neg = sp->neg;
390 	int i;
391 
392 	KASSERT(neg != NULL, ("%s: no neg", __func__));
393 	if ((i = neg->numtags++) < NUMTAGS) {
394 		neg->tags[i] = tp;
395 	} else {
396 		log(LOG_NOTICE, "ng_pppoe: asked to add too many tags to "
397 		    "packet\n");
398 		neg->numtags--;
399 	}
400 }
401 
402 /*
403  * Make up a packet, using the tags filled out for the session.
404  *
405  * Assume that the actual pppoe header and ethernet header
406  * are filled out externally to this routine.
407  * Also assume that neg->wh points to the correct
408  * location at the front of the buffer space.
409  */
410 static void
411 make_packet(sessp sp) {
412 	struct pppoe_full_hdr *wh = &sp->neg->pkt->pkt_header;
413 	const struct pppoe_tag **tag;
414 	char *dp;
415 	int count;
416 	int tlen;
417 	uint16_t length = 0;
418 
419 	KASSERT((sp->neg != NULL) && (sp->neg->m != NULL),
420 	    ("%s: called from wrong state", __func__));
421 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
422 
423 	dp = (char *)(&wh->ph + 1);
424 	for (count = 0, tag = sp->neg->tags;
425 	    ((count < sp->neg->numtags) && (count < NUMTAGS));
426 	    tag++, count++) {
427 		tlen = ntohs((*tag)->tag_len) + sizeof(**tag);
428 		if ((length + tlen) > (ETHER_MAX_LEN - 4 - sizeof(*wh))) {
429 			log(LOG_NOTICE, "ng_pppoe: tags too long\n");
430 			sp->neg->numtags = count;
431 			break;	/* XXX chop off what's too long */
432 		}
433 		bcopy(*tag, (char *)dp, tlen);
434 		length += tlen;
435 		dp += tlen;
436 	}
437  	wh->ph.length = htons(length);
438 	sp->neg->m->m_len = length + sizeof(*wh);
439 	sp->neg->m->m_pkthdr.len = length + sizeof(*wh);
440 }
441 
442 /**************************************************************************
443  * Routines to match a service.						  *
444  **************************************************************************/
445 
446 /*
447  * Find a hook that has a service string that matches that
448  * we are seeking. For now use a simple string.
449  * In the future we may need something like regexp().
450  *
451  * Null string is a wildcard (ANY service), according to RFC2516.
452  * And historical FreeBSD wildcard is also "*".
453  */
454 
455 static hook_p
456 pppoe_match_svc(node_p node, const struct pppoe_tag *tag)
457 {
458 	const priv_p privp = NG_NODE_PRIVATE(node);
459 	sessp sp;
460 
461 	LIST_FOREACH(sp, &privp->listeners, sessions) {
462 		negp neg = sp->neg;
463 
464 		/* Empty Service-Name matches any service. */
465 		if (neg->service_len == 0)
466 			break;
467 
468 		/* Special case for a blank or "*" service name (wildcard). */
469 		if (neg->service_len == 1 && neg->service.data[0] == '*')
470 			break;
471 
472 		/* If the lengths don't match, that aint it. */
473 		if (neg->service_len != ntohs(tag->tag_len))
474 			continue;
475 
476 		if (strncmp((const char *)(tag + 1), neg->service.data,
477 		    ntohs(tag->tag_len)) == 0)
478 			break;
479 	}
480 	CTR3(KTR_NET, "%20s: matched %p for %s", __func__,
481 	    sp?sp->hook:NULL, (const char *)(tag + 1));
482 
483 	return (sp?sp->hook:NULL);
484 }
485 
486 /*
487  * Broadcast the PADI packet in m0 to all listening hooks.
488  * This routine is called when a PADI with empty Service-Name
489  * tag is received. Client should receive PADOs with all
490  * available services.
491  */
492 static int
493 pppoe_broadcast_padi(node_p node, struct mbuf *m0)
494 {
495 	const priv_p privp = NG_NODE_PRIVATE(node);
496 	sessp sp;
497 	int error = 0;
498 
499 	LIST_FOREACH(sp, &privp->listeners, sessions) {
500 		struct mbuf *m;
501 
502 		m = m_dup(m0, M_NOWAIT);
503 		if (m == NULL)
504 			return (ENOMEM);
505 		NG_SEND_DATA_ONLY(error, sp->hook, m);
506 		if (error)
507 			return (error);
508 	}
509 
510 	return (0);
511 }
512 
513 /*
514  * Find a hook, which name equals to given service.
515  */
516 static hook_p
517 pppoe_find_svc(node_p node, const char *svc_name, int svc_len)
518 {
519 	const priv_p privp = NG_NODE_PRIVATE(node);
520 	sessp sp;
521 
522 	LIST_FOREACH(sp, &privp->listeners, sessions) {
523 		negp neg = sp->neg;
524 
525 		if (neg->service_len == svc_len &&
526 		    strncmp(svc_name, neg->service.data, svc_len) == 0)
527 			return (sp->hook);
528 	}
529 
530 	return (NULL);
531 }
532 
533 /**************************************************************************
534  * Routines to find a particular session that matches an incoming packet. *
535  **************************************************************************/
536 /* Find free session and add to hash. */
537 static uint16_t
538 pppoe_getnewsession(sessp sp)
539 {
540 	const priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
541 	static uint16_t pppoe_sid = 1;
542 	sessp	tsp;
543 	uint16_t val, hash;
544 
545 restart:
546 	/* Atomicity is not needed here as value will be checked. */
547 	val = pppoe_sid++;
548 	/* Spec says 0xFFFF is reserved, also don't use 0x0000. */
549 	if (val == 0xffff || val == 0x0000)
550 		val = pppoe_sid = 1;
551 
552 	/* Check it isn't already in use. */
553 	hash = SESSHASH(val);
554 	mtx_lock(&privp->sesshash[hash].mtx);
555 	LIST_FOREACH(tsp, &privp->sesshash[hash].head, sessions) {
556 		if (tsp->Session_ID == val)
557 			break;
558 	}
559 	if (!tsp) {
560 		sp->Session_ID = val;
561 		LIST_INSERT_HEAD(&privp->sesshash[hash].head, sp, sessions);
562 	}
563 	mtx_unlock(&privp->sesshash[hash].mtx);
564 	if (tsp)
565 		goto restart;
566 
567 	CTR2(KTR_NET, "%20s: new sid %d", __func__, val);
568 
569 	return (val);
570 }
571 
572 /* Add specified session to hash. */
573 static void
574 pppoe_addsession(sessp sp)
575 {
576 	const priv_p	privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
577 	uint16_t	hash = SESSHASH(sp->Session_ID);
578 
579 	mtx_lock(&privp->sesshash[hash].mtx);
580 	LIST_INSERT_HEAD(&privp->sesshash[hash].head, sp, sessions);
581 	mtx_unlock(&privp->sesshash[hash].mtx);
582 }
583 
584 /* Delete specified session from hash. */
585 static void
586 pppoe_delsession(sessp sp)
587 {
588 	const priv_p	privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
589 	uint16_t	hash = SESSHASH(sp->Session_ID);
590 
591 	mtx_lock(&privp->sesshash[hash].mtx);
592 	LIST_REMOVE(sp, sessions);
593 	mtx_unlock(&privp->sesshash[hash].mtx);
594 }
595 
596 /* Find matching peer/session combination. */
597 static sessp
598 pppoe_findsession(priv_p privp, const struct pppoe_full_hdr *wh)
599 {
600 	uint16_t 	session = ntohs(wh->ph.sid);
601 	uint16_t	hash = SESSHASH(session);
602 	sessp		sp = NULL;
603 
604 	mtx_lock(&privp->sesshash[hash].mtx);
605 	LIST_FOREACH(sp, &privp->sesshash[hash].head, sessions) {
606 		if (sp->Session_ID == session &&
607 		    bcmp(sp->pkt_hdr.eh.ether_dhost,
608 		     wh->eh.ether_shost, ETHER_ADDR_LEN) == 0) {
609 			break;
610 		}
611 	}
612 	mtx_unlock(&privp->sesshash[hash].mtx);
613 	CTR3(KTR_NET, "%20s: matched %p for %d", __func__, sp?sp->hook:NULL,
614 	    session);
615 
616 	return (sp);
617 }
618 
619 static hook_p
620 pppoe_finduniq(node_p node, const struct pppoe_tag *tag)
621 {
622 	hook_p	hook = NULL;
623 	sessp	sp;
624 
625 	/* Cycle through all known hooks. */
626 	LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
627 		/* Skip any nonsession hook. */
628 		if (NG_HOOK_PRIVATE(hook) == NULL)
629 			continue;
630 		sp = NG_HOOK_PRIVATE(hook);
631 		/* Skip already connected sessions. */
632 		if (sp->neg == NULL)
633 			continue;
634 		if (sp->neg->host_uniq_len == ntohs(tag->tag_len) &&
635 		    bcmp(sp->neg->host_uniq.data, (const char *)(tag + 1),
636 		     sp->neg->host_uniq_len) == 0)
637 			break;
638 	}
639 	CTR3(KTR_NET, "%20s: matched %p for %p", __func__, hook, sp);
640 
641 	return (hook);
642 }
643 
644 static hook_p
645 pppoe_findcookie(node_p node, const struct pppoe_tag *tag)
646 {
647 	hook_p	hook = NULL;
648 	union uniq cookie;
649 
650 	bcopy(tag + 1, cookie.bytes, sizeof(void *));
651 	/* Cycle through all known hooks. */
652 	LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
653 		/* Skip any nonsession hook. */
654 		if (NG_HOOK_PRIVATE(hook) == NULL)
655 			continue;
656 		if (cookie.pointer == NG_HOOK_PRIVATE(hook))
657 			break;
658 	}
659 	CTR3(KTR_NET, "%20s: matched %p for %p", __func__, hook, cookie.pointer);
660 
661 	return (hook);
662 }
663 
664 /**************************************************************************
665  * Start of Netgraph entrypoints.					  *
666  **************************************************************************/
667 
668 /*
669  * Allocate the private data structure and link it with node.
670  */
671 static int
672 ng_pppoe_constructor(node_p node)
673 {
674 	priv_p	privp;
675 	int	i;
676 
677 	/* Initialize private descriptor. */
678 	privp = malloc(sizeof(*privp), M_NETGRAPH_PPPOE, M_WAITOK | M_ZERO);
679 
680 	/* Link structs together; this counts as our one reference to *node. */
681 	NG_NODE_SET_PRIVATE(node, privp);
682 	privp->node = node;
683 
684 	/* Initialize to standard mode. */
685 	memset(&privp->eh.ether_dhost, 0xff, ETHER_ADDR_LEN);
686 	privp->eh.ether_type = ETHERTYPE_PPPOE_DISC;
687 
688 	LIST_INIT(&privp->listeners);
689 	for (i = 0; i < SESSHASHSIZE; i++) {
690 	    mtx_init(&privp->sesshash[i].mtx, "PPPoE hash mutex", NULL, MTX_DEF);
691 	    LIST_INIT(&privp->sesshash[i].head);
692 	}
693 
694 	CTR3(KTR_NET, "%20s: created node [%x] (%p)",
695 	    __func__, node->nd_ID, node);
696 
697 	return (0);
698 }
699 
700 /*
701  * Give our ok for a hook to be added...
702  * point the hook's private info to the hook structure.
703  *
704  * The following hook names are special:
705  *  "ethernet":  the hook that should be connected to a NIC.
706  *  "debug":	copies of data sent out here  (when I write the code).
707  * All other hook names need only be unique. (the framework checks this).
708  */
709 static int
710 ng_pppoe_newhook(node_p node, hook_p hook, const char *name)
711 {
712 	const priv_p privp = NG_NODE_PRIVATE(node);
713 	sessp sp;
714 
715 	if (strcmp(name, NG_PPPOE_HOOK_ETHERNET) == 0) {
716 		privp->ethernet_hook = hook;
717 		NG_HOOK_SET_RCVDATA(hook, ng_pppoe_rcvdata_ether);
718 	} else if (strcmp(name, NG_PPPOE_HOOK_DEBUG) == 0) {
719 		privp->debug_hook = hook;
720 		NG_HOOK_SET_RCVDATA(hook, ng_pppoe_rcvdata_debug);
721 	} else {
722 		/*
723 		 * Any other unique name is OK.
724 		 * The infrastructure has already checked that it's unique,
725 		 * so just allocate it and hook it in.
726 		 */
727 		sp = malloc(sizeof(*sp), M_NETGRAPH_PPPOE, M_NOWAIT | M_ZERO);
728 		if (sp == NULL)
729 			return (ENOMEM);
730 
731 		NG_HOOK_SET_PRIVATE(hook, sp);
732 		sp->hook = hook;
733 	}
734 	CTR5(KTR_NET, "%20s: node [%x] (%p) connected hook %s (%p)",
735 	    __func__, node->nd_ID, node, name, hook);
736 
737 	return(0);
738 }
739 
740 /*
741  * Hook has been added successfully. Request the MAC address of
742  * the underlying Ethernet node.
743  */
744 static int
745 ng_pppoe_connect(hook_p hook)
746 {
747 	const priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
748 	struct ng_mesg *msg;
749 	int error;
750 
751 	if (hook != privp->ethernet_hook)
752 		return (0);
753 
754 	/*
755 	 * If this is Ethernet hook, then request MAC address
756 	 * from our downstream.
757 	 */
758 	NG_MKMESSAGE(msg, NGM_ETHER_COOKIE, NGM_ETHER_GET_ENADDR, 0, M_NOWAIT);
759 	if (msg == NULL)
760 		return (ENOBUFS);
761 
762 	/*
763 	 * Our hook and peer hook have HK_INVALID flag set,
764 	 * so we can't use NG_SEND_MSG_HOOK() macro here.
765 	 */
766 	NG_SEND_MSG_ID(error, privp->node, msg,
767 	    NG_NODE_ID(NG_PEER_NODE(privp->ethernet_hook)),
768 	    NG_NODE_ID(privp->node));
769 
770 	return (error);
771 }
772 /*
773  * Get a netgraph control message.
774  * Check it is one we understand. If needed, send a response.
775  * We sometimes save the address for an async action later.
776  * Always free the message.
777  */
778 static int
779 ng_pppoe_rcvmsg(node_p node, item_p item, hook_p lasthook)
780 {
781 	struct epoch_tracker et;
782 	priv_p privp = NG_NODE_PRIVATE(node);
783 	struct ngpppoe_init_data *ourmsg = NULL;
784 	struct ng_mesg *resp = NULL;
785 	int error = 0;
786 	hook_p hook = NULL;
787 	sessp sp = NULL;
788 	negp neg = NULL;
789 	struct ng_mesg *msg;
790 
791 	NGI_GET_MSG(item, msg);
792 	CTR5(KTR_NET, "%20s: node [%x] (%p) got message %d with cookie %d",
793 	    __func__, node->nd_ID, node, msg->header.cmd,
794 	    msg->header.typecookie);
795 
796 	/* Deal with message according to cookie and command. */
797 	switch (msg->header.typecookie) {
798 	case NGM_PPPOE_COOKIE:
799 		switch (msg->header.cmd) {
800 		case NGM_PPPOE_CONNECT:
801 		case NGM_PPPOE_LISTEN:
802 		case NGM_PPPOE_OFFER:
803 		case NGM_PPPOE_SERVICE:
804 		case NGM_PPPOE_SEND_HURL:
805 		case NGM_PPPOE_SEND_MOTM:
806 			ourmsg = (struct ngpppoe_init_data *)msg->data;
807 			if (msg->header.arglen < sizeof(*ourmsg)) {
808 				log(LOG_ERR, "ng_pppoe[%x]: init data too "
809 				    "small\n", node->nd_ID);
810 				LEAVE(EMSGSIZE);
811 			}
812 			if (msg->header.cmd == NGM_PPPOE_SEND_HURL ||
813 			    msg->header.cmd == NGM_PPPOE_SEND_MOTM) {
814 				if (msg->header.arglen - sizeof(*ourmsg) >
815 				    PPPOE_PADM_VALUE_SIZE) {
816 					log(LOG_ERR, "ng_pppoe[%x]: message "
817 					    "too big\n", node->nd_ID);
818 					LEAVE(EMSGSIZE);
819 				}
820 			} else {
821 				if (msg->header.arglen - sizeof(*ourmsg) >
822 				    PPPOE_SERVICE_NAME_SIZE) {
823 					log(LOG_ERR, "ng_pppoe[%x]: service name "
824 					    "too big\n", node->nd_ID);
825 					LEAVE(EMSGSIZE);
826 				}
827 			}
828 			if (msg->header.arglen - sizeof(*ourmsg) <
829 			    ourmsg->data_len) {
830 				log(LOG_ERR, "ng_pppoe[%x]: init data has bad "
831 				    "length, %d should be %zd\n", node->nd_ID,
832 				    ourmsg->data_len,
833 				    msg->header.arglen - sizeof (*ourmsg));
834 				LEAVE(EMSGSIZE);
835 			}
836 
837 			/* Make sure strcmp will terminate safely. */
838 			ourmsg->hook[sizeof(ourmsg->hook) - 1] = '\0';
839 
840 			/* Find hook by name. */
841 			hook = ng_findhook(node, ourmsg->hook);
842 			if (hook == NULL)
843 				LEAVE(ENOENT);
844 
845 			sp = NG_HOOK_PRIVATE(hook);
846 			if (sp == NULL)
847 				LEAVE(EINVAL);
848 
849 			if (msg->header.cmd == NGM_PPPOE_LISTEN) {
850 				/*
851 				 * Ensure we aren't already listening for this
852 				 * service.
853 				 */
854 				if (pppoe_find_svc(node, ourmsg->data,
855 				    ourmsg->data_len) != NULL)
856 					LEAVE(EEXIST);
857 			}
858 
859 			/*
860 			 * PPPOE_SERVICE advertisements are set up
861 			 * on sessions that are in PRIMED state.
862 			 */
863 			if (msg->header.cmd == NGM_PPPOE_SERVICE)
864 				break;
865 
866 			/*
867 			 * PADM messages are set up on active sessions.
868 			 */
869 			if (msg->header.cmd == NGM_PPPOE_SEND_HURL ||
870 			    msg->header.cmd == NGM_PPPOE_SEND_MOTM) {
871 				if (sp->state != PPPOE_NEWCONNECTED &&
872 				    sp->state != PPPOE_CONNECTED) {
873 					log(LOG_NOTICE, "ng_pppoe[%x]: session is not "
874 					    "active\n", node->nd_ID);
875 					LEAVE(EISCONN);
876 				}
877 				break;
878 			}
879 
880 			if (sp->state != PPPOE_SNONE) {
881 				log(LOG_NOTICE, "ng_pppoe[%x]: Session already "
882 				    "active\n", node->nd_ID);
883 				LEAVE(EISCONN);
884 			}
885 
886 			/*
887 			 * Set up prototype header.
888 			 */
889 			neg = malloc(sizeof(*neg), M_NETGRAPH_PPPOE,
890 			    M_NOWAIT | M_ZERO);
891 
892 			if (neg == NULL)
893 				LEAVE(ENOMEM);
894 
895 			neg->m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
896 			if (neg->m == NULL) {
897 				free(neg, M_NETGRAPH_PPPOE);
898 				LEAVE(ENOBUFS);
899 			}
900 			neg->m->m_pkthdr.rcvif = NULL;
901 			sp->neg = neg;
902 			ng_callout_init(&neg->handle);
903 			neg->m->m_len = sizeof(struct pppoe_full_hdr);
904 			neg->pkt = mtod(neg->m, union packet*);
905 			memcpy((void *)&neg->pkt->pkt_header.eh,
906 			    &privp->eh, sizeof(struct ether_header));
907 			neg->pkt->pkt_header.ph.ver = 0x1;
908 			neg->pkt->pkt_header.ph.type = 0x1;
909 			neg->pkt->pkt_header.ph.sid = 0x0000;
910 			neg->timeout = 0;
911 
912 			sp->creator = NGI_RETADDR(item);
913 		}
914 		switch (msg->header.cmd) {
915 		case NGM_PPPOE_GET_STATUS:
916 		    {
917 			struct ngpppoestat *stats;
918 
919 			NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT);
920 			if (!resp)
921 				LEAVE(ENOMEM);
922 
923 			stats = (struct ngpppoestat *) resp->data;
924 			stats->packets_in = privp->packets_in;
925 			stats->packets_out = privp->packets_out;
926 			break;
927 		    }
928 		case NGM_PPPOE_CONNECT:
929 		    {
930 			/*
931 			 * Check the hook exists and is Uninitialised.
932 			 * Send a PADI request, and start the timeout logic.
933 			 * Store the originator of this message so we can send
934 			 * a success or fail message to them later.
935 			 * Move the session to SINIT.
936 			 * Set up the session to the correct state and
937 			 * start it.
938 			 */
939 			int	acnpos, acnlen = 0, acnsep = 0;
940 			int	hupos, hulen = 0, husep = 0;
941 			int	i, srvpos, srvlen;
942 			acnpos = 0;
943 			for (i = 0; i < ourmsg->data_len; i++) {
944 				if (ourmsg->data[i] == '\\') {
945 					acnlen = i;
946 					acnsep = 1;
947 					break;
948 				}
949 			}
950 			hupos = acnlen + acnsep;
951 			for (i = hupos; i < ourmsg->data_len; i++) {
952 				if (ourmsg->data[i] == '|') {
953 					hulen = i - hupos;
954 					husep = 1;
955 					break;
956 				}
957 			}
958 			srvpos = hupos + hulen + husep;
959 			srvlen = ourmsg->data_len - srvpos;
960 
961 			bcopy(ourmsg->data + acnpos, neg->ac_name.data, acnlen);
962 			neg->ac_name_len = acnlen;
963 
964 			neg->host_uniq.hdr.tag_type = PTT_HOST_UNIQ;
965 			if (hulen == 0) {
966 				/* Not provided, generate one */
967 				neg->host_uniq.hdr.tag_len = htons(sizeof(sp));
968 				bcopy(&sp, neg->host_uniq.data, sizeof(sp));
969 				neg->host_uniq_len = sizeof(sp);
970 			} else if (hulen > 2 && ourmsg->data[hupos] == '0' &&
971 			  ourmsg->data[hupos + 1] == 'x' && hulen % 2 == 0) {
972 				/* Hex encoded */
973 				static const char hexdig[16] = "0123456789abcdef";
974 				int j;
975 
976 				neg->host_uniq.hdr.tag_len = htons((uint16_t)(hulen / 2 - 1));
977 				for (i = 0; i < hulen - 2; i++) {
978 					for (j = 0;
979 					     j < 16 &&
980 					     ourmsg->data[hupos + 2 + i] != hexdig[j];
981 					     j++);
982 					if (j == 16)
983 						LEAVE(EINVAL);
984 					if (i % 2 == 0)
985 						neg->host_uniq.data[i / 2] = j << 4;
986 					else
987 						neg->host_uniq.data[i / 2] |= j;
988 				}
989 				neg->host_uniq_len = hulen / 2 - 1;
990 			} else {
991 				/* Plain string */
992 				neg->host_uniq.hdr.tag_len = htons((uint16_t)hulen);
993 				bcopy(ourmsg->data + hupos, neg->host_uniq.data, hulen);
994 				neg->host_uniq_len = hulen;
995 			}
996 
997 			neg->service.hdr.tag_type = PTT_SRV_NAME;
998 			neg->service.hdr.tag_len = htons((uint16_t)srvlen);
999 			bcopy(ourmsg->data + srvpos, neg->service.data, srvlen);
1000 			neg->service_len = srvlen;
1001 			NET_EPOCH_ENTER(et);
1002 			pppoe_start(sp);
1003 			NET_EPOCH_EXIT(et);
1004 			break;
1005 		    }
1006 		case NGM_PPPOE_LISTEN:
1007 			/*
1008 			 * Check the hook exists and is Uninitialised.
1009 			 * Install the service matching string.
1010 			 * Store the originator of this message so we can send
1011 			 * a success or fail message to them later.
1012 			 * Move the hook to 'LISTENING'
1013 			 */
1014 			neg->service.hdr.tag_type = PTT_SRV_NAME;
1015 			neg->service.hdr.tag_len =
1016 			    htons((uint16_t)ourmsg->data_len);
1017 
1018 			if (ourmsg->data_len)
1019 				bcopy(ourmsg->data, neg->service.data,
1020 				    ourmsg->data_len);
1021 			neg->service_len = ourmsg->data_len;
1022 			neg->pkt->pkt_header.ph.code = PADT_CODE;
1023 			/*
1024 			 * Wait for PADI packet coming from Ethernet.
1025 			 */
1026 			sp->state = PPPOE_LISTENING;
1027 			LIST_INSERT_HEAD(&privp->listeners, sp, sessions);
1028 			break;
1029 		case NGM_PPPOE_OFFER:
1030 			/*
1031 			 * Check the hook exists and is Uninitialised.
1032 			 * Store the originator of this message so we can send
1033 			 * a success of fail message to them later.
1034 			 * Store the AC-Name given and go to PRIMED.
1035 			 */
1036 			neg->ac_name.hdr.tag_type = PTT_AC_NAME;
1037 			neg->ac_name.hdr.tag_len =
1038 			    htons((uint16_t)ourmsg->data_len);
1039 			if (ourmsg->data_len)
1040 				bcopy(ourmsg->data, neg->ac_name.data,
1041 				    ourmsg->data_len);
1042 			neg->ac_name_len = ourmsg->data_len;
1043 			neg->pkt->pkt_header.ph.code = PADO_CODE;
1044 			/*
1045 			 * Wait for PADI packet coming from hook.
1046 			 */
1047 			sp->state = PPPOE_PRIMED;
1048 			break;
1049 		case NGM_PPPOE_SERVICE:
1050 			/*
1051 			 * Check the session is primed.
1052 			 * for now just allow ONE service to be advertised.
1053 			 * If you do it twice you just overwrite.
1054 			 */
1055 			if (sp->state != PPPOE_PRIMED) {
1056 				log(LOG_NOTICE, "ng_pppoe[%x]: session not "
1057 				    "primed\n", node->nd_ID);
1058 				LEAVE(EISCONN);
1059 			}
1060 			neg = sp->neg;
1061 			neg->service.hdr.tag_type = PTT_SRV_NAME;
1062 			neg->service.hdr.tag_len =
1063 			    htons((uint16_t)ourmsg->data_len);
1064 
1065 			if (ourmsg->data_len)
1066 				bcopy(ourmsg->data, neg->service.data,
1067 				    ourmsg->data_len);
1068 			neg->service_len = ourmsg->data_len;
1069 			break;
1070 		case NGM_PPPOE_SETMODE:
1071 		    {
1072 			char *s;
1073 			size_t len;
1074 
1075 			if (msg->header.arglen == 0)
1076 				LEAVE(EINVAL);
1077 
1078 			s = (char *)msg->data;
1079 			len = msg->header.arglen - 1;
1080 
1081 			/* Search for matching mode string. */
1082 			if (len == strlen(NG_PPPOE_STANDARD) &&
1083 			    (strncmp(NG_PPPOE_STANDARD, s, len) == 0)) {
1084 				privp->flags = 0;
1085 				privp->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1086 				break;
1087 			}
1088 			if (len == strlen(NG_PPPOE_3COM) &&
1089 			    (strncmp(NG_PPPOE_3COM, s, len) == 0)) {
1090 				privp->flags |= COMPAT_3COM;
1091 				privp->eh.ether_type =
1092 				    ETHERTYPE_PPPOE_3COM_DISC;
1093 				break;
1094 			}
1095 			if (len == strlen(NG_PPPOE_DLINK) &&
1096 			    (strncmp(NG_PPPOE_DLINK, s, len) == 0)) {
1097 				privp->flags |= COMPAT_DLINK;
1098 				break;
1099 			}
1100 			error = EINVAL;
1101 			break;
1102 		    }
1103 		case NGM_PPPOE_GETMODE:
1104 		    {
1105 			char *s;
1106 			size_t len = 0;
1107 
1108 			if (privp->flags == 0)
1109 				len += strlen(NG_PPPOE_STANDARD) + 1;
1110 			if (privp->flags & COMPAT_3COM)
1111 				len += strlen(NG_PPPOE_3COM) + 1;
1112 			if (privp->flags & COMPAT_DLINK)
1113 				len += strlen(NG_PPPOE_DLINK) + 1;
1114 
1115 			NG_MKRESPONSE(resp, msg, len, M_NOWAIT);
1116 			if (resp == NULL)
1117 				LEAVE(ENOMEM);
1118 
1119 			s = (char *)resp->data;
1120 			if (privp->flags == 0) {
1121 				len = strlen(NG_PPPOE_STANDARD);
1122 				strlcpy(s, NG_PPPOE_STANDARD, len + 1);
1123 				break;
1124 			}
1125 			if (privp->flags & COMPAT_3COM) {
1126 				len = strlen(NG_PPPOE_3COM);
1127 				strlcpy(s, NG_PPPOE_3COM, len + 1);
1128 				s += len;
1129 			}
1130 			if (privp->flags & COMPAT_DLINK) {
1131 				if (s != resp->data)
1132 					*s++ = '|';
1133 				len = strlen(NG_PPPOE_DLINK);
1134 				strlcpy(s, NG_PPPOE_DLINK, len + 1);
1135 			}
1136 			break;
1137 		    }
1138 		case NGM_PPPOE_SETENADDR:
1139 			if (msg->header.arglen != ETHER_ADDR_LEN)
1140 				LEAVE(EINVAL);
1141 			bcopy(msg->data, &privp->eh.ether_shost,
1142 			    ETHER_ADDR_LEN);
1143 			break;
1144 		case NGM_PPPOE_SETMAXP:
1145 			if (msg->header.arglen != sizeof(uint16_t))
1146 				LEAVE(EINVAL);
1147 			privp->max_payload.hdr.tag_type = PTT_MAX_PAYL;
1148 			privp->max_payload.hdr.tag_len = htons(sizeof(uint16_t));
1149 			privp->max_payload.data = htons(*((uint16_t *)msg->data));
1150 			break;
1151 		case NGM_PPPOE_SEND_HURL:
1152 		    {
1153 			struct mbuf *m;
1154 
1155 			/* Generate a packet of that type. */
1156 			m = m_gethdr(M_NOWAIT, MT_DATA);
1157 			if (m == NULL)
1158 				log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
1159 				    "mbufs\n", node->nd_ID);
1160 			else {
1161 				struct pppoe_full_hdr *wh;
1162 				struct pppoe_tag *tag;
1163 				int     error = 0;
1164 
1165 				wh = mtod(m, struct pppoe_full_hdr *);
1166 				bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1167 
1168 				/* Revert the stored header to DISC/PADM mode. */
1169 				wh->ph.code = PADM_CODE;
1170 				/*
1171 				 * Configure ethertype depending on what
1172 				 * was used during sessions stage.
1173 				 */
1174 				if (wh->eh.ether_type ==
1175 				    ETHERTYPE_PPPOE_3COM_SESS)
1176 					wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
1177 				else
1178 					wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1179 				/*
1180 				 * Add PADM message and adjust sizes.
1181 				 */
1182 				tag = (void *)(&wh->ph + 1);
1183 				tag->tag_type = PTT_HURL;
1184 				tag->tag_len = htons(ourmsg->data_len);
1185 				strncpy((char *)(tag + 1), ourmsg->data, ourmsg->data_len);
1186 				m->m_pkthdr.len = m->m_len = sizeof(*wh) + sizeof(*tag) +
1187 				    ourmsg->data_len;
1188 				wh->ph.length = htons(sizeof(*tag) + ourmsg->data_len);
1189 				NET_EPOCH_ENTER(et);
1190 				NG_SEND_DATA_ONLY(error,
1191 				    privp->ethernet_hook, m);
1192 				NET_EPOCH_EXIT(et);
1193 			}
1194 			break;
1195 		    }
1196 		case NGM_PPPOE_SEND_MOTM:
1197 		    {
1198 			struct mbuf *m;
1199 
1200 			/* Generate a packet of that type. */
1201 			m = m_gethdr(M_NOWAIT, MT_DATA);
1202 			if (m == NULL)
1203 				log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
1204 				    "mbufs\n", node->nd_ID);
1205 			else {
1206 				struct pppoe_full_hdr *wh;
1207 				struct pppoe_tag *tag;
1208 				int     error = 0;
1209 
1210 				wh = mtod(m, struct pppoe_full_hdr *);
1211 				bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1212 
1213 				/* Revert the stored header to DISC/PADM mode. */
1214 				wh->ph.code = PADM_CODE;
1215 				/*
1216 				 * Configure ethertype depending on what
1217 				 * was used during sessions stage.
1218 				 */
1219 				if (wh->eh.ether_type ==
1220 				    ETHERTYPE_PPPOE_3COM_SESS)
1221 					wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
1222 				else
1223 					wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1224 				/*
1225 				 * Add PADM message and adjust sizes.
1226 				 */
1227 				tag = (void *)(&wh->ph + 1);
1228 				tag->tag_type = PTT_MOTM;
1229 				tag->tag_len = htons(ourmsg->data_len);
1230 				strncpy((char *)(tag + 1), ourmsg->data, ourmsg->data_len);
1231 				m->m_pkthdr.len = m->m_len = sizeof(*wh) + sizeof(*tag) +
1232 				    ourmsg->data_len;
1233 				wh->ph.length = htons(sizeof(*tag) + ourmsg->data_len);
1234 				NET_EPOCH_ENTER(et);
1235 				NG_SEND_DATA_ONLY(error,
1236 				    privp->ethernet_hook, m);
1237 				NET_EPOCH_EXIT(et);
1238 			}
1239 			break;
1240 		    }
1241 		default:
1242 			LEAVE(EINVAL);
1243 		}
1244 		break;
1245 	case NGM_ETHER_COOKIE:
1246 		if (!(msg->header.flags & NGF_RESP))
1247 			LEAVE(EINVAL);
1248 		switch (msg->header.cmd) {
1249 		case NGM_ETHER_GET_ENADDR:
1250 			if (msg->header.arglen != ETHER_ADDR_LEN)
1251 				LEAVE(EINVAL);
1252 			bcopy(msg->data, &privp->eh.ether_shost,
1253 			    ETHER_ADDR_LEN);
1254 			break;
1255 		default:
1256 			LEAVE(EINVAL);
1257 		}
1258 		break;
1259 	default:
1260 		LEAVE(EINVAL);
1261 	}
1262 
1263 	/* Take care of synchronous response, if any. */
1264 quit:
1265 	CTR2(KTR_NET, "%20s: returning %d", __func__, error);
1266 	NG_RESPOND_MSG(error, node, item, resp);
1267 	/* Free the message and return. */
1268 	NG_FREE_MSG(msg);
1269 	return(error);
1270 }
1271 
1272 /*
1273  * Start a client into the first state. A separate function because
1274  * it can be needed if the negotiation times out.
1275  */
1276 static void
1277 pppoe_start(sessp sp)
1278 {
1279 	hook_p	hook = sp->hook;
1280 	node_p	node = NG_HOOK_NODE(hook);
1281 	priv_p	privp = NG_NODE_PRIVATE(node);
1282 	negp	neg = sp->neg;
1283 	struct  mbuf *m0;
1284 	int	error;
1285 
1286 	/*
1287 	 * Kick the state machine into starting up.
1288 	 */
1289 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1290 	sp->state = PPPOE_SINIT;
1291 	/*
1292 	 * Reset the packet header to broadcast. Since we are
1293 	 * in a client mode use configured ethertype.
1294 	 */
1295 	memcpy((void *)&neg->pkt->pkt_header.eh, &privp->eh,
1296 	    sizeof(struct ether_header));
1297 	neg->pkt->pkt_header.ph.code = PADI_CODE;
1298 	init_tags(sp);
1299 	insert_tag(sp, &neg->host_uniq.hdr);
1300 	insert_tag(sp, &neg->service.hdr);
1301 	if (privp->max_payload.data != 0)
1302 		insert_tag(sp, &privp->max_payload.hdr);
1303 	make_packet(sp);
1304 	/*
1305 	 * Send packet and prepare to retransmit it after timeout.
1306 	 */
1307 	ng_callout(&neg->handle, node, hook, PPPOE_INITIAL_TIMEOUT * hz,
1308 	    pppoe_ticker, NULL, 0);
1309 	neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1310 	m0 = m_copypacket(neg->m, M_NOWAIT);
1311 	NG_SEND_DATA_ONLY(error, privp->ethernet_hook, m0);
1312 }
1313 
1314 static int
1315 send_acname(sessp sp, const struct pppoe_tag *tag)
1316 {
1317 	int error, tlen;
1318 	struct ng_mesg *msg;
1319 	struct ngpppoe_sts *sts;
1320 
1321 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1322 
1323 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_ACNAME,
1324 	    sizeof(struct ngpppoe_sts), M_NOWAIT);
1325 	if (msg == NULL)
1326 		return (ENOMEM);
1327 
1328 	sts = (struct ngpppoe_sts *)msg->data;
1329 	tlen = min(NG_HOOKSIZ - 1, ntohs(tag->tag_len));
1330 	strncpy(sts->hook, (const char *)(tag + 1), tlen);
1331 	sts->hook[tlen] = '\0';
1332 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1333 
1334 	return (error);
1335 }
1336 
1337 static int
1338 send_sessionid(sessp sp)
1339 {
1340 	int error;
1341 	struct ng_mesg *msg;
1342 
1343 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1344 
1345 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SESSIONID,
1346 	    sizeof(uint16_t), M_NOWAIT);
1347 	if (msg == NULL)
1348 		return (ENOMEM);
1349 
1350 	*(uint16_t *)msg->data = sp->Session_ID;
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_maxp(sessp sp, const struct pppoe_tag *tag)
1358 {
1359 	int error;
1360 	struct ng_mesg *msg;
1361 	struct ngpppoe_maxp *maxp;
1362 
1363 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1364 
1365 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SETMAXP,
1366 	    sizeof(struct ngpppoe_maxp), M_NOWAIT);
1367 	if (msg == NULL)
1368 		return (ENOMEM);
1369 
1370 	maxp = (struct ngpppoe_maxp *)msg->data;
1371 	strncpy(maxp->hook, NG_HOOK_NAME(sp->hook), NG_HOOKSIZ);
1372 	maxp->data = ntohs(((const struct maxptag *)tag)->data);
1373 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1374 
1375 	return (error);
1376 }
1377 
1378 static int
1379 send_hurl(sessp sp, const struct pppoe_tag *tag)
1380 {
1381 	int error, tlen;
1382 	struct ng_mesg *msg;
1383 	struct ngpppoe_padm *padm;
1384 
1385 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1386 
1387 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_HURL,
1388 	    sizeof(struct ngpppoe_padm), M_NOWAIT);
1389 	if (msg == NULL)
1390 		return (ENOMEM);
1391 
1392 	padm = (struct ngpppoe_padm *)msg->data;
1393 	tlen = min(PPPOE_PADM_VALUE_SIZE - 1, ntohs(tag->tag_len));
1394 	strncpy(padm->msg, (const char *)(tag + 1), tlen);
1395 	padm->msg[tlen] = '\0';
1396 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1397 
1398 	return (error);
1399 }
1400 
1401 static int
1402 send_motm(sessp sp, const struct pppoe_tag *tag)
1403 {
1404 	int error, tlen;
1405 	struct ng_mesg *msg;
1406 	struct ngpppoe_padm *padm;
1407 
1408 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1409 
1410 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_MOTM,
1411 	    sizeof(struct ngpppoe_padm), M_NOWAIT);
1412 	if (msg == NULL)
1413 		return (ENOMEM);
1414 
1415 	padm = (struct ngpppoe_padm *)msg->data;
1416 	tlen = min(PPPOE_PADM_VALUE_SIZE - 1, ntohs(tag->tag_len));
1417 	strncpy(padm->msg, (const char *)(tag + 1), tlen);
1418 	padm->msg[tlen] = '\0';
1419 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1420 
1421 	return (error);
1422 }
1423 
1424 /*
1425  * Receive data from session hook and do something with it.
1426  */
1427 static int
1428 ng_pppoe_rcvdata(hook_p hook, item_p item)
1429 {
1430 	node_p			node = NG_HOOK_NODE(hook);
1431 	const priv_p		privp = NG_NODE_PRIVATE(node);
1432 	sessp			sp = NG_HOOK_PRIVATE(hook);
1433 	struct pppoe_full_hdr	*wh;
1434 	struct mbuf		*m;
1435 	int			error;
1436 
1437 	CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1438 	    __func__, node->nd_ID, node, item, hook->hk_name, hook);
1439 
1440 	NGI_GET_M(item, m);
1441 	switch (sp->state) {
1442 	case	PPPOE_NEWCONNECTED:
1443 	case	PPPOE_CONNECTED: {
1444 		/*
1445 		 * Remove PPP address and control fields, if any.
1446 		 * For example, ng_ppp(4) always sends LCP packets
1447 		 * with address and control fields as required by
1448 		 * generic PPP. PPPoE is an exception to the rule.
1449 		 */
1450 		if (m->m_pkthdr.len >= 2) {
1451 			if (m->m_len < 2 && !(m = m_pullup(m, 2)))
1452 				LEAVE(ENOBUFS);
1453 			if (mtod(m, u_char *)[0] == 0xff &&
1454 			    mtod(m, u_char *)[1] == 0x03)
1455 				m_adj(m, 2);
1456 		}
1457 
1458 		if (V_ng_pppoe_lcp_pcp && m->m_pkthdr.len >= 2 &&
1459 		    m->m_len >= 2 && (m = m_pullup(m, 2)) &&
1460 		    mtod(m, uint16_t *)[0] == htons(PROT_LCP))
1461 			EVL_APPLY_PRI(m, (uint8_t)(V_ng_pppoe_lcp_pcp & 0x7));
1462 
1463 		/*
1464 		 * Bang in a pre-made header, and set the length up
1465 		 * to be correct. Then send it to the ethernet driver.
1466 		 */
1467 		M_PREPEND(m, sizeof(*wh), M_NOWAIT);
1468 		if (m == NULL)
1469 			LEAVE(ENOBUFS);
1470 
1471 		wh = mtod(m, struct pppoe_full_hdr *);
1472 		bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1473 		wh->ph.length = htons(m->m_pkthdr.len - sizeof(*wh));
1474 		NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m);
1475 		privp->packets_out++;
1476 		break;
1477 		}
1478 	case	PPPOE_PRIMED: {
1479 		struct {
1480 			struct pppoe_tag hdr;
1481 			union	uniq	data;
1482 		} __packed 	uniqtag;
1483 		const struct pppoe_tag	*tag;
1484 		struct mbuf 	*m0;
1485 		const struct pppoe_hdr	*ph;
1486 		negp		neg = sp->neg;
1487 		uint8_t		code;
1488 
1489 		/*
1490 		 * A PADI packet is being returned by the application
1491 		 * that has set up this hook. This indicates that it
1492 		 * wants us to offer service.
1493 		 */
1494 		if (m->m_len < sizeof(*wh)) {
1495 			m = m_pullup(m, sizeof(*wh));
1496 			if (m == NULL)
1497 				LEAVE(ENOBUFS);
1498 		}
1499 		wh = mtod(m, struct pppoe_full_hdr *);
1500 		ph = &wh->ph;
1501 		code = wh->ph.code;
1502 		/* Use peers mode in session. */
1503 		neg->pkt->pkt_header.eh.ether_type = wh->eh.ether_type;
1504 		if (code != PADI_CODE)
1505 			LEAVE(EINVAL);
1506 		ng_uncallout(&neg->handle, node);
1507 
1508 		/*
1509 		 * This is the first time we hear
1510 		 * from the client, so note it's
1511 		 * unicast address, replacing the
1512 		 * broadcast address.
1513 		 */
1514 		bcopy(wh->eh.ether_shost,
1515 			neg->pkt->pkt_header.eh.ether_dhost,
1516 			ETHER_ADDR_LEN);
1517 		sp->state = PPPOE_SOFFER;
1518 		neg->timeout = 0;
1519 		neg->pkt->pkt_header.ph.code = PADO_CODE;
1520 
1521 		/*
1522 		 * Start working out the tags to respond with.
1523 		 */
1524 		uniqtag.hdr.tag_type = PTT_AC_COOKIE;
1525 		uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(sp));
1526 		uniqtag.data.pointer = sp;
1527 		init_tags(sp);
1528 		insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1529 		if ((tag = get_tag(ph, PTT_SRV_NAME)))
1530 			insert_tag(sp, tag);	  /* return service */
1531 		/*
1532 		 * If we have a NULL service request
1533 		 * and have an extra service defined in this hook,
1534 		 * then also add a tag for the extra service.
1535 		 * XXX this is a hack. eventually we should be able
1536 		 * to support advertising many services, not just one
1537 		 */
1538 		if (((tag == NULL) || (tag->tag_len == 0)) &&
1539 		    (neg->service.hdr.tag_len != 0)) {
1540 			insert_tag(sp, &neg->service.hdr); /* SERVICE */
1541 		}
1542 		if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1543 			insert_tag(sp, tag); /* returned hostunique */
1544 		insert_tag(sp, &uniqtag.hdr);
1545 		scan_tags(sp, ph);
1546 		make_packet(sp);
1547 		/*
1548 		 * Send the offer but if they don't respond
1549 		 * in PPPOE_OFFER_TIMEOUT seconds, forget about it.
1550 		 */
1551 		ng_callout(&neg->handle, node, hook, PPPOE_OFFER_TIMEOUT * hz,
1552 		    pppoe_ticker, NULL, 0);
1553 		m0 = m_copypacket(sp->neg->m, M_NOWAIT);
1554 		NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1555 		privp->packets_out++;
1556 		break;
1557 		}
1558 
1559 	/*
1560 	 * Packets coming from the hook make no sense
1561 	 * to sessions in the rest of states. Throw them away.
1562 	 */
1563 	default:
1564 		LEAVE(ENETUNREACH);
1565 	}
1566 quit:
1567 	if (item)
1568 		NG_FREE_ITEM(item);
1569 	NG_FREE_M(m);
1570 	return (error);
1571 }
1572 
1573 /*
1574  * Receive data from ether and do something with it.
1575  */
1576 static int
1577 ng_pppoe_rcvdata_ether(hook_p hook, item_p item)
1578 {
1579 	node_p			node = NG_HOOK_NODE(hook);
1580 	const priv_p		privp = NG_NODE_PRIVATE(node);
1581 	sessp			sp;
1582 	const struct pppoe_tag	*utag = NULL, *tag = NULL;
1583 	const struct pppoe_tag	sntag = { PTT_SRV_NAME, 0 };
1584 	const struct pppoe_full_hdr *wh;
1585 	const struct pppoe_hdr	*ph;
1586 	negp			neg = NULL;
1587 	struct mbuf		*m;
1588 	hook_p 			sendhook;
1589 	int			error = 0;
1590 	uint16_t		length;
1591 	uint8_t			code;
1592 	struct	mbuf 		*m0;
1593 
1594 	CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1595 	    __func__, node->nd_ID, node, item, hook->hk_name, hook);
1596 
1597 	NGI_GET_M(item, m);
1598 	/*
1599 	 * Dig out various fields from the packet.
1600 	 * Use them to decide where to send it.
1601 	 */
1602 	privp->packets_in++;
1603 	if( m->m_len < sizeof(*wh)) {
1604 		m = m_pullup(m, sizeof(*wh)); /* Checks length */
1605 		if (m == NULL) {
1606 			log(LOG_NOTICE, "ng_pppoe[%x]: couldn't "
1607 			    "m_pullup(wh)\n", node->nd_ID);
1608 			LEAVE(ENOBUFS);
1609 		}
1610 	}
1611 	wh = mtod(m, struct pppoe_full_hdr *);
1612 	length = ntohs(wh->ph.length);
1613 	switch(wh->eh.ether_type) {
1614 	case	ETHERTYPE_PPPOE_3COM_DISC: /* fall through */
1615 	case	ETHERTYPE_PPPOE_DISC:
1616 		/*
1617 		 * We need to try to make sure that the tag area
1618 		 * is contiguous, or we could wander off the end
1619 		 * of a buffer and make a mess.
1620 		 * (Linux wouldn't have this problem).
1621 		 */
1622 		if (m->m_pkthdr.len <= MHLEN) {
1623 			if( m->m_len < m->m_pkthdr.len) {
1624 				m = m_pullup(m, m->m_pkthdr.len);
1625 				if (m == NULL) {
1626 					log(LOG_NOTICE, "ng_pppoe[%x]: "
1627 					    "couldn't m_pullup(pkthdr)\n",
1628 					    node->nd_ID);
1629 					LEAVE(ENOBUFS);
1630 				}
1631 			}
1632 		}
1633 		if (m->m_len != m->m_pkthdr.len) {
1634 			/*
1635 			 * It's not all in one piece.
1636 			 * We need to do extra work.
1637 			 * Put it into a cluster.
1638 			 */
1639 			struct mbuf *n;
1640 			n = m_dup(m, M_NOWAIT);
1641 			m_freem(m);
1642 			m = n;
1643 			if (m) {
1644 				/* just check we got a cluster */
1645 				if (m->m_len != m->m_pkthdr.len) {
1646 					m_freem(m);
1647 					m = NULL;
1648 				}
1649 			}
1650 			if (m == NULL) {
1651 				log(LOG_NOTICE, "ng_pppoe[%x]: packet "
1652 				    "fragmented\n", node->nd_ID);
1653 				LEAVE(EMSGSIZE);
1654 			}
1655 		}
1656 		wh = mtod(m, struct pppoe_full_hdr *);
1657 		length = ntohs(wh->ph.length);
1658 		ph = &wh->ph;
1659 		code = wh->ph.code;
1660 
1661 		switch(code) {
1662 		case	PADI_CODE:
1663 			/*
1664 			 * We are a server:
1665 			 * Look for a hook with the required service and send
1666 			 * the ENTIRE packet up there. It should come back to
1667 			 * a new hook in PRIMED state. Look there for further
1668 			 * processing.
1669 			 */
1670 			tag = get_tag(ph, PTT_SRV_NAME);
1671 			if (tag == NULL)
1672 				tag = &sntag;
1673 
1674 			/*
1675 			 * First, try to match Service-Name against our
1676 			 * listening hooks. If no success and we are in D-Link
1677 			 * compat mode and Service-Name is empty, then we
1678 			 * broadcast the PADI to all listening hooks.
1679 			 */
1680 			sendhook = pppoe_match_svc(node, tag);
1681 			if (sendhook != NULL)
1682 				NG_FWD_NEW_DATA(error, item, sendhook, m);
1683 			else if (privp->flags & COMPAT_DLINK &&
1684 				 ntohs(tag->tag_len) == 0)
1685 				error = pppoe_broadcast_padi(node, m);
1686 			else
1687 				error = ENETUNREACH;
1688 			break;
1689 		case	PADO_CODE:
1690 			/*
1691 			 * We are a client:
1692 			 * Use the host_uniq tag to find the hook this is in
1693 			 * response to. Received #2, now send #3
1694 			 * For now simply accept the first we receive.
1695 			 */
1696 			utag = get_tag(ph, PTT_HOST_UNIQ);
1697 			if (utag == NULL) {
1698 				log(LOG_NOTICE, "ng_pppoe[%x]: no host "
1699 				    "unique field\n", node->nd_ID);
1700 				LEAVE(ENETUNREACH);
1701 			}
1702 
1703 			sendhook = pppoe_finduniq(node, utag);
1704 			if (sendhook == NULL) {
1705 				log(LOG_NOTICE, "ng_pppoe[%x]: no "
1706 				    "matching session\n", node->nd_ID);
1707 				LEAVE(ENETUNREACH);
1708 			}
1709 
1710 			/*
1711 			 * Check the session is in the right state.
1712 			 * It needs to be in PPPOE_SINIT.
1713 			 */
1714 			sp = NG_HOOK_PRIVATE(sendhook);
1715 			if (sp->state == PPPOE_SREQ ||
1716 			    sp->state == PPPOE_CONNECTED) {
1717 				break;	/* Multiple PADO is OK. */
1718 			}
1719 			if (sp->state != PPPOE_SINIT) {
1720 				log(LOG_NOTICE, "ng_pppoe[%x]: session "
1721 				    "in wrong state\n", node->nd_ID);
1722 				LEAVE(ENETUNREACH);
1723 			}
1724 			neg = sp->neg;
1725 			/* If requested specific AC-name, check it. */
1726 			if (neg->ac_name_len) {
1727 				tag = get_tag(ph, PTT_AC_NAME);
1728 				if (!tag) {
1729 					/* No PTT_AC_NAME in PADO */
1730 					break;
1731 				}
1732 				if (neg->ac_name_len != htons(tag->tag_len) ||
1733 				    strncmp(neg->ac_name.data,
1734 				    (const char *)(tag + 1),
1735 				    neg->ac_name_len) != 0) {
1736 					break;
1737 				}
1738 			}
1739 			sp->state = PPPOE_SREQ;
1740 			ng_uncallout(&neg->handle, node);
1741 
1742 			/*
1743 			 * This is the first time we hear
1744 			 * from the server, so note it's
1745 			 * unicast address, replacing the
1746 			 * broadcast address .
1747 			 */
1748 			bcopy(wh->eh.ether_shost,
1749 				neg->pkt->pkt_header.eh.ether_dhost,
1750 				ETHER_ADDR_LEN);
1751 			neg->timeout = 0;
1752 			neg->pkt->pkt_header.ph.code = PADR_CODE;
1753 			init_tags(sp);
1754 			insert_tag(sp, utag);      	/* Host Unique */
1755 			if ((tag = get_tag(ph, PTT_AC_COOKIE)))
1756 				insert_tag(sp, tag); 	/* return cookie */
1757 			if ((tag = get_tag(ph, PTT_AC_NAME))) {
1758 				insert_tag(sp, tag); 	/* return it */
1759 				send_acname(sp, tag);
1760 			}
1761 			if ((tag = get_tag(ph, PTT_MAX_PAYL)) &&
1762 			    (privp->max_payload.data != 0))
1763 				insert_tag(sp, tag);	/* return it */
1764 			insert_tag(sp, &neg->service.hdr); /* Service */
1765 			scan_tags(sp, ph);
1766 			make_packet(sp);
1767 			sp->state = PPPOE_SREQ;
1768 			ng_callout(&neg->handle, node, sp->hook,
1769 			    PPPOE_INITIAL_TIMEOUT * hz,
1770 			    pppoe_ticker, NULL, 0);
1771 			neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1772 			m0 = m_copypacket(neg->m, M_NOWAIT);
1773 			NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1774 			break;
1775 		case	PADR_CODE:
1776 			/*
1777 			 * We are a server:
1778 			 * Use the ac_cookie tag to find the
1779 			 * hook this is in response to.
1780 			 */
1781 			utag = get_tag(ph, PTT_AC_COOKIE);
1782 			if ((utag == NULL) ||
1783 			    (ntohs(utag->tag_len) != sizeof(sp))) {
1784 				LEAVE(ENETUNREACH);
1785 			}
1786 
1787 			sendhook = pppoe_findcookie(node, utag);
1788 			if (sendhook == NULL)
1789 				LEAVE(ENETUNREACH);
1790 
1791 			/*
1792 			 * Check the session is in the right state.
1793 			 * It needs to be in PPPOE_SOFFER or PPPOE_NEWCONNECTED.
1794 			 * If the latter, then this is a retry by the client,
1795 			 * so be nice, and resend.
1796 			 */
1797 			sp = NG_HOOK_PRIVATE(sendhook);
1798 			if (sp->state == PPPOE_NEWCONNECTED) {
1799 				/*
1800 				 * Whoa! drop back to resend that PADS packet.
1801 				 * We should still have a copy of it.
1802 				 */
1803 				sp->state = PPPOE_SOFFER;
1804 			} else if (sp->state != PPPOE_SOFFER)
1805 				LEAVE (ENETUNREACH);
1806 			neg = sp->neg;
1807 			ng_uncallout(&neg->handle, node);
1808 			neg->pkt->pkt_header.ph.code = PADS_CODE;
1809 			if (sp->Session_ID == 0) {
1810 				neg->pkt->pkt_header.ph.sid =
1811 				    htons(pppoe_getnewsession(sp));
1812 			}
1813 			send_sessionid(sp);
1814 			neg->timeout = 0;
1815 			/*
1816 			 * start working out the tags to respond with.
1817 			 */
1818 			init_tags(sp);
1819 			insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1820 			if ((tag = get_tag(ph, PTT_SRV_NAME)))
1821 				insert_tag(sp, tag);/* return service */
1822 			if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1823 				insert_tag(sp, tag); /* return it */
1824 			insert_tag(sp, utag);	/* ac_cookie */
1825 			scan_tags(sp, ph);
1826 			make_packet(sp);
1827 			sp->state = PPPOE_NEWCONNECTED;
1828 
1829 			/* Send the PADS without a timeout - we're now connected. */
1830 			m0 = m_copypacket(sp->neg->m, M_NOWAIT);
1831 			NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1832 
1833 			/*
1834 			 * Having sent the last Negotiation header,
1835 			 * Set up the stored packet header to be correct for
1836 			 * the actual session. But keep the negotialtion stuff
1837 			 * around in case we need to resend this last packet.
1838 			 * We'll discard it when we move from NEWCONNECTED
1839 			 * to CONNECTED
1840 			 */
1841 			sp->pkt_hdr = neg->pkt->pkt_header;
1842 			/* Configure ethertype depending on what
1843 			 * ethertype was used at discovery phase */
1844 			if (sp->pkt_hdr.eh.ether_type ==
1845 			    ETHERTYPE_PPPOE_3COM_DISC)
1846 				sp->pkt_hdr.eh.ether_type
1847 					= ETHERTYPE_PPPOE_3COM_SESS;
1848 			else
1849 				sp->pkt_hdr.eh.ether_type
1850 					= ETHERTYPE_PPPOE_SESS;
1851 			sp->pkt_hdr.ph.code = 0;
1852 			pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1853 			break;
1854 		case	PADS_CODE:
1855 			/*
1856 			 * We are a client:
1857 			 * Use the host_uniq tag to find the hook this is in
1858 			 * response to. Take the session ID and store it away.
1859 			 * Also make sure the pre-made header is correct and
1860 			 * set us into Session mode.
1861 			 */
1862 			utag = get_tag(ph, PTT_HOST_UNIQ);
1863 			if (utag == NULL) {
1864 				LEAVE (ENETUNREACH);
1865 			}
1866 			sendhook = pppoe_finduniq(node, utag);
1867 			if (sendhook == NULL)
1868 				LEAVE(ENETUNREACH);
1869 
1870 			/*
1871 			 * Check the session is in the right state.
1872 			 * It needs to be in PPPOE_SREQ.
1873 			 */
1874 			sp = NG_HOOK_PRIVATE(sendhook);
1875 			if (sp->state != PPPOE_SREQ)
1876 				LEAVE(ENETUNREACH);
1877 			neg = sp->neg;
1878 			ng_uncallout(&neg->handle, node);
1879 			neg->pkt->pkt_header.ph.sid = wh->ph.sid;
1880 			sp->Session_ID = ntohs(wh->ph.sid);
1881 			pppoe_addsession(sp);
1882 			send_sessionid(sp);
1883 			neg->timeout = 0;
1884 			sp->state = PPPOE_CONNECTED;
1885 			/*
1886 			 * Now we have gone to Connected mode,
1887 			 * Free all resources needed for negotiation.
1888 			 * Keep a copy of the header we will be using.
1889 			 */
1890 			sp->pkt_hdr = neg->pkt->pkt_header;
1891 			if (privp->flags & COMPAT_3COM)
1892 				sp->pkt_hdr.eh.ether_type
1893 					= ETHERTYPE_PPPOE_3COM_SESS;
1894 			else
1895 				sp->pkt_hdr.eh.ether_type
1896 					= ETHERTYPE_PPPOE_SESS;
1897 			sp->pkt_hdr.ph.code = 0;
1898 			m_freem(neg->m);
1899 			free(sp->neg, M_NETGRAPH_PPPOE);
1900 			sp->neg = NULL;
1901 			if ((tag = get_tag(ph, PTT_MAX_PAYL)) &&
1902 			    (privp->max_payload.data != 0))
1903 				send_maxp(sp, tag);
1904 			pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1905 			break;
1906 		case	PADT_CODE:
1907 			/*
1908 			 * Find matching peer/session combination.
1909 			 */
1910 			sp = pppoe_findsession(privp, wh);
1911 			if (sp == NULL)
1912 				LEAVE(ENETUNREACH);
1913 			/* Disconnect that hook. */
1914 			ng_rmhook_self(sp->hook);
1915 			break;
1916 		case	PADM_CODE:
1917 			/*
1918 			 * We are a client:
1919 			 * find matching peer/session combination.
1920 			 */
1921 			sp = pppoe_findsession(privp, wh);
1922 			if (sp == NULL)
1923 				LEAVE (ENETUNREACH);
1924 			if ((tag = get_tag(ph, PTT_HURL)))
1925 				send_hurl(sp, tag);
1926 			if ((tag = get_tag(ph, PTT_MOTM)))
1927 				send_motm(sp, tag);
1928 			break;
1929 		default:
1930 			LEAVE(EPFNOSUPPORT);
1931 		}
1932 		break;
1933 	case	ETHERTYPE_PPPOE_3COM_SESS:
1934 	case	ETHERTYPE_PPPOE_SESS:
1935 		/*
1936 		 * Find matching peer/session combination.
1937 		 */
1938 		sp = pppoe_findsession(privp, wh);
1939 		if (sp == NULL)
1940 			LEAVE (ENETUNREACH);
1941 		m_adj(m, sizeof(*wh));
1942 
1943 		/* If packet too short, dump it. */
1944 		if (m->m_pkthdr.len < length)
1945 			LEAVE(EMSGSIZE);
1946 		/* Also need to trim excess at the end */
1947 		if (m->m_pkthdr.len > length) {
1948 			m_adj(m, -((int)(m->m_pkthdr.len - length)));
1949 		}
1950 		if ( sp->state != PPPOE_CONNECTED) {
1951 			if (sp->state == PPPOE_NEWCONNECTED) {
1952 				sp->state = PPPOE_CONNECTED;
1953 				/*
1954 				 * Now we have gone to Connected mode,
1955 				 * Free all resources needed for negotiation.
1956 				 * Be paranoid about whether there may be
1957 				 * a timeout.
1958 				 */
1959 				m_freem(sp->neg->m);
1960 				ng_uncallout(&sp->neg->handle, node);
1961 				free(sp->neg, M_NETGRAPH_PPPOE);
1962 				sp->neg = NULL;
1963 			} else {
1964 				LEAVE (ENETUNREACH);
1965 			}
1966 		}
1967 		NG_FWD_NEW_DATA(error, item, sp->hook, m);
1968 		break;
1969 	default:
1970 		LEAVE(EPFNOSUPPORT);
1971 	}
1972 quit:
1973 	if (item)
1974 		NG_FREE_ITEM(item);
1975 	NG_FREE_M(m);
1976 	return (error);
1977 }
1978 
1979 /*
1980  * Receive data from debug hook and bypass it to ether.
1981  */
1982 static int
1983 ng_pppoe_rcvdata_debug(hook_p hook, item_p item)
1984 {
1985 	node_p		node = NG_HOOK_NODE(hook);
1986 	const priv_p	privp = NG_NODE_PRIVATE(node);
1987 	int		error;
1988 
1989 	CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1990 	    __func__, node->nd_ID, node, item, hook->hk_name, hook);
1991 
1992 	NG_FWD_ITEM_HOOK(error, item, privp->ethernet_hook);
1993 	privp->packets_out++;
1994 	return (error);
1995 }
1996 
1997 /*
1998  * Do local shutdown processing..
1999  * If we are a persistent device, we might refuse to go away, and
2000  * we'd only remove our links and reset ourself.
2001  */
2002 static int
2003 ng_pppoe_shutdown(node_p node)
2004 {
2005 	const priv_p privp = NG_NODE_PRIVATE(node);
2006 	int	i;
2007 
2008 	for (i = 0; i < SESSHASHSIZE; i++)
2009 	    mtx_destroy(&privp->sesshash[i].mtx);
2010 	NG_NODE_SET_PRIVATE(node, NULL);
2011 	NG_NODE_UNREF(privp->node);
2012 	free(privp, M_NETGRAPH_PPPOE);
2013 	return (0);
2014 }
2015 
2016 /*
2017  * Hook disconnection
2018  *
2019  * Clean up all dangling links and information about the session/hook.
2020  * For this type, removal of the last link destroys the node.
2021  */
2022 static int
2023 ng_pppoe_disconnect(hook_p hook)
2024 {
2025 	node_p node = NG_HOOK_NODE(hook);
2026 	priv_p privp = NG_NODE_PRIVATE(node);
2027 	sessp	sp;
2028 
2029 	if (hook == privp->debug_hook) {
2030 		privp->debug_hook = NULL;
2031 	} else if (hook == privp->ethernet_hook) {
2032 		privp->ethernet_hook = NULL;
2033 		if (NG_NODE_IS_VALID(node))
2034 			ng_rmnode_self(node);
2035 	} else {
2036 		sp = NG_HOOK_PRIVATE(hook);
2037 		if (sp->state != PPPOE_SNONE ) {
2038 			pppoe_send_event(sp, NGM_PPPOE_CLOSE);
2039 		}
2040 		/*
2041 		 * According to the spec, if we are connected,
2042 		 * we should send a DISC packet if we are shutting down
2043 		 * a session.
2044 		 */
2045 		if ((privp->ethernet_hook)
2046 		&& ((sp->state == PPPOE_CONNECTED)
2047 		 || (sp->state == PPPOE_NEWCONNECTED))) {
2048 			struct mbuf *m;
2049 
2050 			/* Generate a packet of that type. */
2051 			m = m_gethdr(M_NOWAIT, MT_DATA);
2052 			if (m == NULL)
2053 				log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
2054 				    "mbufs\n", node->nd_ID);
2055 			else {
2056 				struct epoch_tracker et;
2057 				struct pppoe_full_hdr *wh;
2058 				struct pppoe_tag *tag;
2059 				int	msglen = strlen(SIGNOFF);
2060 				int	error = 0;
2061 
2062 				wh = mtod(m, struct pppoe_full_hdr *);
2063 				bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
2064 
2065 				/* Revert the stored header to DISC/PADT mode. */
2066 				wh->ph.code = PADT_CODE;
2067 				/*
2068 				 * Configure ethertype depending on what
2069 				 * was used during sessions stage.
2070 				 */
2071 				if (wh->eh.ether_type ==
2072 				    ETHERTYPE_PPPOE_3COM_SESS)
2073 					wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
2074 				else
2075 					wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
2076 				/*
2077 				 * Add a General error message and adjust
2078 				 * sizes.
2079 				 */
2080 				tag = (void *)(&wh->ph + 1);
2081 				tag->tag_type = PTT_GEN_ERR;
2082 				tag->tag_len = htons((u_int16_t)msglen);
2083 				strncpy((char *)(tag + 1), SIGNOFF, msglen);
2084 				m->m_pkthdr.len = m->m_len = sizeof(*wh) + sizeof(*tag) +
2085 				    msglen;
2086 				wh->ph.length = htons(sizeof(*tag) + msglen);
2087 
2088 				NET_EPOCH_ENTER(et);
2089 				NG_SEND_DATA_ONLY(error,
2090 					privp->ethernet_hook, m);
2091 				NET_EPOCH_EXIT(et);
2092 			}
2093 		}
2094 		if (sp->state == PPPOE_LISTENING)
2095 			LIST_REMOVE(sp, sessions);
2096 		else if (sp->Session_ID)
2097 			pppoe_delsession(sp);
2098 		/*
2099 		 * As long as we have somewhere to store the timeout handle,
2100 		 * we may have a timeout pending.. get rid of it.
2101 		 */
2102 		if (sp->neg) {
2103 			ng_uncallout(&sp->neg->handle, node);
2104 			if (sp->neg->m)
2105 				m_freem(sp->neg->m);
2106 			free(sp->neg, M_NETGRAPH_PPPOE);
2107 		}
2108 		free(sp, M_NETGRAPH_PPPOE);
2109 		NG_HOOK_SET_PRIVATE(hook, NULL);
2110 	}
2111 	if ((NG_NODE_NUMHOOKS(node) == 0) &&
2112 	    (NG_NODE_IS_VALID(node)))
2113 		ng_rmnode_self(node);
2114 	return (0);
2115 }
2116 
2117 /*
2118  * Timeouts come here.
2119  */
2120 static void
2121 pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2)
2122 {
2123 	priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
2124 	sessp	sp = NG_HOOK_PRIVATE(hook);
2125 	negp	neg = sp->neg;
2126 	struct mbuf *m0 = NULL;
2127 	int	error = 0;
2128 
2129 	CTR6(KTR_NET, "%20s: node [%x] (%p) hook \"%s\" (%p) session %d",
2130 	    __func__, node->nd_ID, node, hook->hk_name, hook, sp->Session_ID);
2131 	switch(sp->state) {
2132 		/*
2133 		 * Resend the last packet, using an exponential backoff.
2134 		 * After a period of time, stop growing the backoff,
2135 		 * And either leave it, or revert to the start.
2136 		 */
2137 	case	PPPOE_SINIT:
2138 	case	PPPOE_SREQ:
2139 		/* Timeouts on these produce resends. */
2140 		m0 = m_copypacket(sp->neg->m, M_NOWAIT);
2141 		NG_SEND_DATA_ONLY( error, privp->ethernet_hook, m0);
2142 		ng_callout(&neg->handle, node, hook, neg->timeout * hz,
2143 		    pppoe_ticker, NULL, 0);
2144 		if ((neg->timeout <<= 1) > PPPOE_TIMEOUT_LIMIT) {
2145 			if (sp->state == PPPOE_SREQ) {
2146 				/* Revert to SINIT mode. */
2147 				pppoe_start(sp);
2148 			} else {
2149 				neg->timeout = PPPOE_TIMEOUT_LIMIT;
2150 			}
2151 		}
2152 		break;
2153 	case	PPPOE_PRIMED:
2154 	case	PPPOE_SOFFER:
2155 		/* A timeout on these says "give up" */
2156 		ng_rmhook_self(hook);
2157 		break;
2158 	default:
2159 		/* Timeouts have no meaning in other states. */
2160 		log(LOG_NOTICE, "ng_pppoe[%x]: unexpected timeout\n",
2161 		    node->nd_ID);
2162 	}
2163 }
2164 
2165 /*
2166  * Parse an incoming packet to see if any tags should be copied to the
2167  * output packet. Don't do any tags that have been handled in the main
2168  * state machine.
2169  */
2170 static const struct pppoe_tag*
2171 scan_tags(sessp	sp, const struct pppoe_hdr* ph)
2172 {
2173 	const char *const end = (const char *)next_tag(ph);
2174 	const char *ptn;
2175 	const struct pppoe_tag *pt = (const void *)(ph + 1);
2176 
2177 	/*
2178 	 * Keep processing tags while a tag header will still fit.
2179 	 */
2180 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
2181 
2182 	while((const char*)(pt + 1) <= end) {
2183 		/*
2184 		 * If the tag data would go past the end of the packet, abort.
2185 		 */
2186 		ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
2187 		if(ptn > end)
2188 			return NULL;
2189 
2190 		switch (pt->tag_type) {
2191 		case	PTT_RELAY_SID:
2192 			insert_tag(sp, pt);
2193 			break;
2194 		case	PTT_EOL:
2195 			return NULL;
2196 		case	PTT_SRV_NAME:
2197 		case	PTT_AC_NAME:
2198 		case	PTT_HOST_UNIQ:
2199 		case	PTT_AC_COOKIE:
2200 		case	PTT_VENDOR:
2201 		case	PTT_SRV_ERR:
2202 		case	PTT_SYS_ERR:
2203 		case	PTT_GEN_ERR:
2204 		case	PTT_MAX_PAYL:
2205 		case	PTT_HURL:
2206 		case	PTT_MOTM:
2207 			break;
2208 		}
2209 		pt = (const struct pppoe_tag*)ptn;
2210 	}
2211 	return NULL;
2212 }
2213 
2214 static	int
2215 pppoe_send_event(sessp sp, enum cmd cmdid)
2216 {
2217 	int error;
2218 	struct ng_mesg *msg;
2219 	struct ngpppoe_sts *sts;
2220 
2221 	CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
2222 
2223 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, cmdid,
2224 			sizeof(struct ngpppoe_sts), M_NOWAIT);
2225 	if (msg == NULL)
2226 		return (ENOMEM);
2227 	sts = (struct ngpppoe_sts *)msg->data;
2228 	strncpy(sts->hook, NG_HOOK_NAME(sp->hook), NG_HOOKSIZ);
2229 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
2230 	return (error);
2231 }
2232