xref: /freebsd/sys/netgraph/ng_pppoe.c (revision 77a0943ded95b9e6438f7db70c4a28e4d93946d4)
1 
2 /*
3  * ng_pppoe.c
4  *
5  * Copyright (c) 1996-1999 Whistle Communications, Inc.
6  * All rights reserved.
7  *
8  * Subject to the following obligations and disclaimer of warranty, use and
9  * redistribution of this software, in source or object code forms, with or
10  * without modifications are expressly permitted by Whistle Communications;
11  * provided, however, that:
12  * 1. Any and all reproductions of the source or object code must include the
13  *    copyright notice above and the following disclaimer of warranties; and
14  * 2. No rights are granted, in any manner or form, to use Whistle
15  *    Communications, Inc. trademarks, including the mark "WHISTLE
16  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
17  *    such appears in the above copyright notice or in the software.
18  *
19  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
20  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
21  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
22  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
23  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
24  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
25  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
26  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
27  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
28  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
29  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
30  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
31  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
35  * OF SUCH DAMAGE.
36  *
37  * Author: Julian Elischer <julian@freebsd.org>
38  *
39  * $FreeBSD$
40  * $Whistle: ng_pppoe.c,v 1.10 1999/11/01 09:24:52 julian Exp $
41  */
42 #if 0
43 #define AAA printf("pppoe: %s\n", __FUNCTION__ );
44 #define BBB printf("-%d-", __LINE__ );
45 #else
46 #define AAA
47 #define BBB
48 #endif
49 
50 #include <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/kernel.h>
53 #include <sys/mbuf.h>
54 #include <sys/malloc.h>
55 #include <sys/errno.h>
56 #include <net/ethernet.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 
63 #define SIGNOFF "session closed"
64 #define OFFSETOF(s, e) ((char *)&((s *)0)->e - (char *)((s *)0))
65 
66 /*
67  * This section contains the netgraph method declarations for the
68  * sample node. These methods define the netgraph 'type'.
69  */
70 
71 static ng_constructor_t	ng_pppoe_constructor;
72 static ng_rcvmsg_t	ng_pppoe_rcvmsg;
73 static ng_shutdown_t	ng_pppoe_rmnode;
74 static ng_newhook_t	ng_pppoe_newhook;
75 static ng_connect_t	ng_pppoe_connect;
76 static ng_rcvdata_t	ng_pppoe_rcvdata;
77 static ng_disconnect_t	ng_pppoe_disconnect;
78 
79 /* Parse type for struct ngpppoe_init_data */
80 static const struct ng_parse_struct_info ngpppoe_init_data_type_info
81 	= NG_PPPOE_INIT_DATA_TYPE_INFO;
82 static const struct ng_parse_type ngpppoe_init_data_state_type = {
83 	&ng_parse_struct_type,
84 	&ngpppoe_init_data_type_info
85 };
86 
87 /* Parse type for struct ngpppoe_sts */
88 static const struct ng_parse_struct_info ng_pppoe_sts_type_info
89 	= NG_PPPOE_STS_TYPE_INFO;
90 static const struct ng_parse_type ng_pppoe_sts_state_type = {
91 	&ng_parse_struct_type,
92 	&ng_pppoe_sts_type_info
93 };
94 
95 /* List of commands and how to convert arguments to/from ASCII */
96 static const struct ng_cmdlist ng_pppoe_cmds[] = {
97 	{
98 	  NGM_PPPOE_COOKIE,
99 	  NGM_PPPOE_CONNECT,
100 	  "pppoe_connect",
101 	  &ngpppoe_init_data_state_type,
102 	  NULL
103 	},
104 	{
105 	  NGM_PPPOE_COOKIE,
106 	  NGM_PPPOE_LISTEN,
107 	  "pppoe_listen",
108 	  &ngpppoe_init_data_state_type,
109 	  NULL
110 	},
111 	{
112 	  NGM_PPPOE_COOKIE,
113 	  NGM_PPPOE_OFFER,
114 	  "pppoe_offer",
115 	  &ngpppoe_init_data_state_type,
116 	  NULL
117 	},
118 	{
119 	  NGM_PPPOE_COOKIE,
120 	  NGM_PPPOE_SUCCESS,
121 	  "pppoe_success",
122 	  &ng_pppoe_sts_state_type,
123 	  NULL
124 	},
125 	{
126 	  NGM_PPPOE_COOKIE,
127 	  NGM_PPPOE_FAIL,
128 	  "pppoe_fail",
129 	  &ng_pppoe_sts_state_type,
130 	  NULL
131 	},
132 	{
133 	  NGM_PPPOE_COOKIE,
134 	  NGM_PPPOE_CLOSE,
135 	  "pppoe_close",
136 	  &ng_pppoe_sts_state_type,
137 	  NULL
138 	},
139 	{ 0 }
140 };
141 
142 /* Netgraph node type descriptor */
143 static struct ng_type typestruct = {
144 	NG_VERSION,
145 	NG_PPPOE_NODE_TYPE,
146 	NULL,
147 	ng_pppoe_constructor,
148 	ng_pppoe_rcvmsg,
149 	ng_pppoe_rmnode,
150 	ng_pppoe_newhook,
151 	NULL,
152 	ng_pppoe_connect,
153 	ng_pppoe_rcvdata,
154 	ng_pppoe_rcvdata,
155 	ng_pppoe_disconnect,
156 	ng_pppoe_cmds
157 };
158 NETGRAPH_INIT(pppoe, &typestruct);
159 
160 /*
161  * States for the session state machine.
162  * These have no meaning if there is no hook attached yet.
163  */
164 enum state {
165     PPPOE_SNONE=0,	/* [both] Initial state */
166     PPPOE_LISTENING,	/* [Daemon] Listening for discover initiation pkt */
167     PPPOE_SINIT,	/* [Client] Sent discovery initiation */
168     PPPOE_PRIMED,	/* [Server] Awaiting PADI from daemon */
169     PPPOE_SOFFER,	/* [Server] Sent offer message  (got PADI)*/
170     PPPOE_SREQ,		/* [Client] Sent a Request */
171     PPPOE_NEWCONNECTED,	/* [Server] Connection established, No data received */
172     PPPOE_CONNECTED,	/* [Both] Connection established, Data received */
173     PPPOE_DEAD		/* [Both] */
174 };
175 
176 #define NUMTAGS 20 /* number of tags we are set up to work with */
177 
178 /*
179  * Information we store for each hook on each node for negotiating the
180  * session. The mbuf and cluster are freed once negotiation has completed.
181  * The whole negotiation block is then discarded.
182  */
183 
184 struct sess_neg {
185 	struct mbuf 		*m; /* holds cluster with last sent packet */
186 	union	packet		*pkt; /* points within the above cluster */
187 	struct callout_handle	timeout_handle;   /* see timeout(9) */
188 	u_int			timeout; /* 0,1,2,4,8,16 etc. seconds */
189 	u_int			numtags;
190 	struct pppoe_tag	*tags[NUMTAGS];
191 	u_int			service_len;
192 	u_int			ac_name_len;
193 
194 	struct datatag		service;
195 	struct datatag		ac_name;
196 };
197 typedef struct sess_neg *negp;
198 
199 /*
200  * Session information that is needed after connection.
201  */
202 struct sess_con {
203 	hook_p  		hook;
204 	u_int16_t		Session_ID;
205 	enum state		state;
206 	char			creator[NG_NODELEN + 1]; /* who to notify */
207 	struct pppoe_full_hdr	pkt_hdr;	/* used when connected */
208 	negp			neg;		/* used when negotiating */
209 	/*struct sess_con	*hash_next;*/	/* not yet used */
210 };
211 typedef struct sess_con *sessp;
212 
213 /*
214  * Information we store for each node
215  */
216 struct PPPOE {
217 	node_p		node;		/* back pointer to node */
218 	hook_p  	ethernet_hook;
219 	hook_p  	debug_hook;
220 	u_int   	packets_in;	/* packets in from ethernet */
221 	u_int   	packets_out;	/* packets out towards ethernet */
222 	u_int32_t	flags;
223 	/*struct sess_con *buckets[HASH_SIZE];*/	/* not yet used */
224 };
225 typedef struct PPPOE *priv_p;
226 
227 const struct ether_header eh_prototype =
228 	{{0xff,0xff,0xff,0xff,0xff,0xff},
229 	 {0x00,0x00,0x00,0x00,0x00,0x00},
230 	 ETHERTYPE_PPPOE_DISC};
231 
232 union uniq {
233 	char bytes[sizeof(void *)];
234 	void * pointer;
235 	};
236 
237 #define	LEAVE(x) do { error = x; goto quit; } while(0)
238 static void	pppoe_start(sessp sp);
239 static void	sendpacket(sessp sp);
240 static void	pppoe_ticker(void *arg);
241 static struct pppoe_tag* scan_tags(sessp	sp, struct pppoe_hdr* ph);
242 static	int	pppoe_send_event(sessp sp, enum cmd cmdid);
243 
244 /*************************************************************************
245  * Some basic utilities  from the Linux version with author's permission.*
246  * Author:	Michal Ostrowski <mostrows@styx.uwaterloo.ca>		 *
247  ************************************************************************/
248 
249 /*
250  * Generate a new session id
251  * XXX find out the FreeBSD locking scheme.
252  */
253 static u_int16_t
254 get_new_sid(node_p node)
255 {
256 	static int pppoe_sid = 10;
257 	sessp sp;
258 	hook_p	hook;
259 	u_int16_t val;
260 	priv_p privp = node->private;
261 
262 AAA
263 restart:
264 	val = pppoe_sid++;
265 	/*
266 	 * Spec says 0xFFFF is reserved.
267 	 * Also don't use 0x0000
268 	 */
269 	if (val == 0xffff) {
270 		pppoe_sid = 20;
271 		goto restart;
272 	}
273 
274 	/* Check it isn't already in use */
275 	LIST_FOREACH(hook, &node->hooks, hooks) {
276 		/* don't check special hooks */
277 		if ((hook->private == &privp->debug_hook)
278 		||  (hook->private == &privp->ethernet_hook))
279 			continue;
280 		sp = hook->private;
281 		if (sp->Session_ID == val)
282 			goto restart;
283 	}
284 
285 	return val;
286 }
287 
288 
289 /*
290  * Return the location where the next tag can be put
291  */
292 static __inline struct pppoe_tag*
293 next_tag(struct pppoe_hdr* ph)
294 {
295 	return (struct pppoe_tag*)(((char*)&ph->tag[0]) + ntohs(ph->length));
296 }
297 
298 /*
299  * Look for a tag of a specific type
300  * Don't trust any length the other end says.
301  * but assume we already sanity checked ph->length.
302  */
303 static struct pppoe_tag*
304 get_tag(struct pppoe_hdr* ph, u_int16_t idx)
305 {
306 	char *end = (char *)next_tag(ph);
307 	char *ptn;
308 	struct pppoe_tag *pt = &ph->tag[0];
309 	/*
310 	 * Keep processing tags while a tag header will still fit.
311 	 */
312 AAA
313 	while((char*)(pt + 1) <= end) {
314 	    /*
315 	     * If the tag data would go past the end of the packet, abort.
316 	     */
317 	    ptn = (((char *)(pt + 1)) + ntohs(pt->tag_len));
318 	    if(ptn > end)
319 		return NULL;
320 
321 	    if(pt->tag_type == idx)
322 		return pt;
323 
324 	    pt = (struct pppoe_tag*)ptn;
325 	}
326 	return NULL;
327 }
328 
329 /**************************************************************************
330  * inlines to initialise or add tags to a session's tag list,
331  **************************************************************************/
332 /*
333  * Initialise the session's tag list
334  */
335 static void
336 init_tags(sessp sp)
337 {
338 AAA
339 	if(sp->neg == NULL) {
340 		printf("pppoe: asked to init NULL neg pointer\n");
341 		return;
342 	}
343 	sp->neg->numtags = 0;
344 }
345 
346 static void
347 insert_tag(sessp sp, struct pppoe_tag *tp)
348 {
349 	int	i;
350 	negp neg;
351 
352 AAA
353 	if((neg = sp->neg) == NULL) {
354 		printf("pppoe: asked to use NULL neg pointer\n");
355 		return;
356 	}
357 	if ((i = neg->numtags++) < NUMTAGS) {
358 		neg->tags[i] = tp;
359 	} else {
360 		printf("pppoe: asked to add too many tags to packet\n");
361 		neg->numtags--;
362 	}
363 }
364 
365 /*
366  * Make up a packet, using the tags filled out for the session.
367  *
368  * Assume that the actual pppoe header and ethernet header
369  * are filled out externally to this routine.
370  * Also assume that neg->wh points to the correct
371  * location at the front of the buffer space.
372  */
373 static void
374 make_packet(sessp sp) {
375 	struct pppoe_full_hdr *wh = &sp->neg->pkt->pkt_header;
376 	struct pppoe_tag **tag;
377 	char *dp;
378 	int count;
379 	int tlen;
380 	u_int16_t length = 0;
381 
382 AAA
383 	if ((sp->neg == NULL) || (sp->neg->m == NULL)) {
384 		printf("pppoe: make_packet called from wrong state\n");
385 	}
386 	dp = (char *)wh->ph.tag;
387 	for (count = 0, tag = sp->neg->tags;
388 	    ((count < sp->neg->numtags) && (count < NUMTAGS));
389 	    tag++, count++) {
390 		tlen = ntohs((*tag)->tag_len) + sizeof(**tag);
391 		if ((length + tlen) > (ETHER_MAX_LEN - 4 - sizeof(*wh))) {
392 			printf("pppoe: tags too long\n");
393 			sp->neg->numtags = count;
394 			break;	/* XXX chop off what's too long */
395 		}
396 		bcopy((char *)*tag, (char *)dp, tlen);
397 		length += tlen;
398 		dp += tlen;
399 	}
400  	wh->ph.length = htons(length);
401 	sp->neg->m->m_len = length + sizeof(*wh);
402 	sp->neg->m->m_pkthdr.len = length + sizeof(*wh);
403 }
404 
405 /**************************************************************************
406  * Routine to match a service offered					  *
407  **************************************************************************/
408 /*
409  * Find a hook that has a service string that matches that
410  * we are seeking. for now use a simple string.
411  * In the future we may need something like regexp().
412  * for testing allow a null string to match 1st found and a null service
413  * to match all requests. Also make '*' do the same.
414  */
415 static hook_p
416 pppoe_match_svc(node_p node, char *svc_name, int svc_len)
417 {
418 	sessp	sp	= NULL;
419 	negp	neg	= NULL;
420 	priv_p	privp	= node->private;
421 	hook_p hook;
422 
423 AAA
424 	LIST_FOREACH(hook, &node->hooks, hooks) {
425 
426 		/* skip any hook that is debug or ethernet */
427 		if ((hook->private == &privp->debug_hook)
428 		||  (hook->private == &privp->ethernet_hook))
429 			continue;
430 		sp = hook->private;
431 
432 		/* Skip any sessions which are not in LISTEN mode. */
433 		if ( sp->state != PPPOE_LISTENING)
434 			continue;
435 
436 		neg = sp->neg;
437 		/* XXX check validity of this */
438 		/* special case, NULL request. match 1st found. */
439 		if (svc_len == 0)
440 			break;
441 
442 		/* XXX check validity of this */
443 		/* Special case for a blank or "*" service name (wildcard) */
444 		if ((neg->service_len == 0)
445 		||  ((neg->service_len == 1)
446 		  && (neg->service.data[0] == '*'))) {
447 			break;
448 		}
449 
450 		/* If the lengths don't match, that aint it. */
451 		if (neg->service_len != svc_len)
452 			continue;
453 
454 		/* An exact match? */
455 		if (strncmp(svc_name, neg->service.data, svc_len) == 0)
456 			break;
457 	}
458 	return (hook);
459 }
460 /**************************************************************************
461  * Routine to find a particular session that matches an incoming packet	  *
462  **************************************************************************/
463 static hook_p
464 pppoe_findsession(node_p node, struct pppoe_full_hdr *wh)
465 {
466 	sessp	sp = NULL;
467 	hook_p hook = NULL;
468 	priv_p	privp = node->private;
469 	u_int16_t	session = ntohs(wh->ph.sid);
470 
471 	/*
472 	 * find matching peer/session combination.
473 	 */
474 AAA
475 	LIST_FOREACH(hook, &node->hooks, hooks) {
476 		/* don't check special hooks */
477 		if ((hook->private == &privp->debug_hook)
478 		||  (hook->private == &privp->ethernet_hook)) {
479 			continue;
480 		}
481 		sp = hook->private;
482 		if ( ( (sp->state == PPPOE_CONNECTED)
483 		    || (sp->state == PPPOE_NEWCONNECTED) )
484 		&& (sp->Session_ID == session)
485 		&& (bcmp(sp->pkt_hdr.eh.ether_dhost,
486 		    wh->eh.ether_shost,
487 		    ETHER_ADDR_LEN)) == 0) {
488 			break;
489 		}
490 	}
491 	return (hook);
492 }
493 
494 static hook_p
495 pppoe_finduniq(node_p node, struct pppoe_tag *tag)
496 {
497 	hook_p hook = NULL;
498 	priv_p	privp = node->private;
499 	union uniq		uniq;
500 
501 AAA
502 	bcopy(tag->tag_data, uniq.bytes, sizeof(void *));
503 	/* cycle through all known hooks */
504 	LIST_FOREACH(hook, &node->hooks, hooks) {
505 		/* don't check special hooks */
506 		if ((hook->private == &privp->debug_hook)
507 		||  (hook->private == &privp->ethernet_hook))
508 			continue;
509 		if (uniq.pointer == hook->private)
510 			break;
511 	}
512 	return (hook);
513 }
514 
515 /**************************************************************************
516  * start of Netgraph entrypoints					  *
517  **************************************************************************/
518 
519 /*
520  * Allocate the private data structure and the generic node
521  * and link them together.
522  *
523  * ng_make_node_common() returns with a generic node struct
524  * with a single reference for us.. we transfer it to the
525  * private structure.. when we free the private struct we must
526  * unref the node so it gets freed too.
527  *
528  * If this were a device node than this work would be done in the attach()
529  * routine and the constructor would return EINVAL as you should not be able
530  * to creatednodes that depend on hardware (unless you can add the hardware :)
531  */
532 static int
533 ng_pppoe_constructor(node_p *nodep)
534 {
535 	priv_p privdata;
536 	int error;
537 
538 AAA
539 	/* Initialize private descriptor */
540 	MALLOC(privdata, priv_p, sizeof(*privdata), M_NETGRAPH,
541 	    M_NOWAIT | M_ZERO);
542 	if (privdata == NULL)
543 		return (ENOMEM);
544 
545 	/* Call the 'generic' (ie, superclass) node constructor */
546 	if ((error = ng_make_node_common(&typestruct, nodep))) {
547 		FREE(privdata, M_NETGRAPH);
548 		return (error);
549 	}
550 
551 	/* Link structs together; this counts as our one reference to *nodep */
552 	(*nodep)->private = privdata;
553 	privdata->node = *nodep;
554 	return (0);
555 }
556 
557 /*
558  * Give our ok for a hook to be added...
559  * point the hook's private info to the hook structure.
560  *
561  * The following hook names are special:
562  *  Ethernet:  the hook that should be connected to a NIC.
563  *  debug:	copies of data sent out here  (when I write the code).
564  */
565 static int
566 ng_pppoe_newhook(node_p node, hook_p hook, const char *name)
567 {
568 	const priv_p privp = node->private;
569 	sessp sp;
570 
571 AAA
572 	if (strcmp(name, NG_PPPOE_HOOK_ETHERNET) == 0) {
573 		privp->ethernet_hook = hook;
574 		hook->private = &privp->ethernet_hook;
575 	} else if (strcmp(name, NG_PPPOE_HOOK_DEBUG) == 0) {
576 		privp->debug_hook = hook;
577 		hook->private = &privp->debug_hook;
578 	} else {
579 		/*
580 		 * Any other unique name is OK.
581 		 * The infrastructure has already checked that it's unique,
582 		 * so just allocate it and hook it in.
583 		 */
584 		MALLOC(sp, sessp, sizeof(*sp), M_NETGRAPH, M_NOWAIT | M_ZERO);
585 		if (sp == NULL) {
586 				return (ENOMEM);
587 		}
588 
589 		hook->private = sp;
590 		sp->hook = hook;
591 	}
592 	return(0);
593 }
594 
595 /*
596  * Get a netgraph control message.
597  * Check it is one we understand. If needed, send a response.
598  * We sometimes save the address for an async action later.
599  * Always free the message.
600  */
601 static int
602 ng_pppoe_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr,
603 		struct ng_mesg **rptr, hook_p lasthook)
604 {
605 	priv_p privp = node->private;
606 	struct ngpppoe_init_data *ourmsg = NULL;
607 	struct ng_mesg *resp = NULL;
608 	int error = 0;
609 	hook_p hook = NULL;
610 	sessp sp = NULL;
611 	negp neg = NULL;
612 
613 AAA
614 	/* Deal with message according to cookie and command */
615 	switch (msg->header.typecookie) {
616 	case NGM_PPPOE_COOKIE:
617 		switch (msg->header.cmd) {
618 		case NGM_PPPOE_CONNECT:
619 		case NGM_PPPOE_LISTEN:
620 		case NGM_PPPOE_OFFER:
621 			ourmsg = (struct ngpppoe_init_data *)msg->data;
622 			if (msg->header.arglen < sizeof(*ourmsg)) {
623 				printf("pppoe: init data too small\n");
624 				LEAVE(EMSGSIZE);
625 			}
626 			if (msg->header.arglen - sizeof(*ourmsg) >
627 			    PPPOE_SERVICE_NAME_SIZE) {
628 				printf("pppoe_rcvmsg: service name too big");
629 				LEAVE(EMSGSIZE);
630 			}
631 			if (msg->header.arglen - sizeof(*ourmsg) <
632 			    ourmsg->data_len) {
633 				printf("pppoe: init data has bad length,"
634 				    " %d should be %d\n", ourmsg->data_len,
635 				    msg->header.arglen - sizeof (*ourmsg));
636 				LEAVE(EMSGSIZE);
637 			}
638 
639 			/* make sure strcmp will terminate safely */
640 			ourmsg->hook[sizeof(ourmsg->hook) - 1] = '\0';
641 
642 			/* cycle through all known hooks */
643 			LIST_FOREACH(hook, &node->hooks, hooks) {
644 				if (hook->name
645 				&& strcmp(hook->name, ourmsg->hook) == 0)
646 					break;
647 			}
648 			if (hook == NULL) {
649 				LEAVE(ENOENT);
650 			}
651 			if ((hook->private == &privp->debug_hook)
652 			||  (hook->private == &privp->ethernet_hook)) {
653 				LEAVE(EINVAL);
654 			}
655 			sp = hook->private;
656 			if (sp->state |= PPPOE_SNONE) {
657 				printf("pppoe: Session already active\n");
658 				LEAVE(EISCONN);
659 			}
660 
661 			/*
662 			 * set up prototype header
663 			 */
664 			MALLOC(neg, negp, sizeof(*neg), M_NETGRAPH,
665 			    M_NOWAIT | M_ZERO);
666 
667 			if (neg == NULL) {
668 				printf("pppoe: Session out of memory\n");
669 				LEAVE(ENOMEM);
670 			}
671 			MGETHDR(neg->m, M_DONTWAIT, MT_DATA);
672 			if(neg->m == NULL) {
673 				printf("pppoe: Session out of mbufs\n");
674 				FREE(neg, M_NETGRAPH);
675 				LEAVE(ENOBUFS);
676 			}
677 			neg->m->m_pkthdr.rcvif = NULL;
678 			MCLGET(neg->m, M_DONTWAIT);
679 			if ((neg->m->m_flags & M_EXT) == 0) {
680 				printf("pppoe: Session out of mcls\n");
681 				m_freem(neg->m);
682 				FREE(neg, M_NETGRAPH);
683 				LEAVE(ENOBUFS);
684 			}
685 			sp->neg = neg;
686 			callout_handle_init( &neg->timeout_handle);
687 			neg->m->m_len = sizeof(struct pppoe_full_hdr);
688 			neg->pkt = mtod(neg->m, union packet*);
689 			neg->pkt->pkt_header.eh = eh_prototype;
690 			neg->pkt->pkt_header.ph.ver = 0x1;
691 			neg->pkt->pkt_header.ph.type = 0x1;
692 			neg->pkt->pkt_header.ph.sid = 0x0000;
693 			neg->timeout = 0;
694 
695 			strncpy(sp->creator, retaddr, NG_NODELEN);
696 			sp->creator[NG_NODELEN] = '\0';
697 		}
698 		switch (msg->header.cmd) {
699 		case NGM_PPPOE_GET_STATUS:
700 		    {
701 			struct ngpppoestat *stats;
702 
703 			NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT);
704 			if (!resp) {
705 				LEAVE(ENOMEM);
706 			}
707 			stats = (struct ngpppoestat *) resp->data;
708 			stats->packets_in = privp->packets_in;
709 			stats->packets_out = privp->packets_out;
710 			break;
711 		    }
712 		case NGM_PPPOE_CONNECT:
713 			/*
714 			 * Check the hook exists and is Uninitialised.
715 			 * Send a PADI request, and start the timeout logic.
716 			 * Store the originator of this message so we can send
717 			 * a success of fail message to them later.
718 			 * Move the session to SINIT
719 			 * Set up the session to the correct state and
720 			 * start it.
721 			 */
722 			neg->service.hdr.tag_type = PTT_SRV_NAME;
723 			neg->service.hdr.tag_len =
724 			    htons((u_int16_t)ourmsg->data_len);
725 			if (ourmsg->data_len)
726 				bcopy(ourmsg->data, neg->service.data,
727 				    ourmsg->data_len);
728 			neg->service_len = ourmsg->data_len;
729 			pppoe_start(sp);
730 			break;
731 		case NGM_PPPOE_LISTEN:
732 			/*
733 			 * Check the hook exists and is Uninitialised.
734 			 * Install the service matching string.
735 			 * Store the originator of this message so we can send
736 			 * a success of fail message to them later.
737 			 * Move the hook to 'LISTENING'
738 
739 			 */
740 			neg->service.hdr.tag_type = PTT_SRV_NAME;
741 			neg->service.hdr.tag_len =
742 			    htons((u_int16_t)ourmsg->data_len);
743 
744 			if (ourmsg->data_len)
745 				bcopy(ourmsg->data, neg->service.data,
746 				    ourmsg->data_len);
747 			neg->service_len = ourmsg->data_len;
748 			neg->pkt->pkt_header.ph.code = PADT_CODE;
749 			/*
750 			 * wait for PADI packet coming from ethernet
751 			 */
752 			sp->state = PPPOE_LISTENING;
753 			break;
754 		case NGM_PPPOE_OFFER:
755 			/*
756 			 * Check the hook exists and is Uninitialised.
757 			 * Store the originator of this message so we can send
758 			 * a success of fail message to them later.
759 			 * Store the AC-Name given and go to PRIMED.
760 			 */
761 			neg->ac_name.hdr.tag_type = PTT_AC_NAME;
762 			neg->ac_name.hdr.tag_len =
763 			    htons((u_int16_t)ourmsg->data_len);
764 			if (ourmsg->data_len)
765 				bcopy(ourmsg->data, neg->ac_name.data,
766 				    ourmsg->data_len);
767 			neg->ac_name_len = ourmsg->data_len;
768 			neg->pkt->pkt_header.ph.code = PADO_CODE;
769 			/*
770 			 * Wait for PADI packet coming from hook
771 			 */
772 			sp->state = PPPOE_PRIMED;
773 			break;
774 		default:
775 			LEAVE(EINVAL);
776 		}
777 		break;
778 	default:
779 		LEAVE(EINVAL);
780 	}
781 
782 	/* Take care of synchronous response, if any */
783 	if (rptr)
784 		*rptr = resp;
785 	else if (resp)
786 		FREE(resp, M_NETGRAPH);
787 
788 	/* Free the message and return */
789 quit:
790 	FREE(msg, M_NETGRAPH);
791 	return(error);
792 }
793 
794 /*
795  * Start a client into the first state. A separate function because
796  * it can be needed if the negotiation times out.
797  */
798 static void
799 pppoe_start(sessp sp)
800 {
801 	struct {
802 		struct pppoe_tag hdr;
803 		union	uniq	data;
804 	} uniqtag;
805 
806 	/*
807 	 * kick the state machine into starting up
808 	 */
809 AAA
810 	sp->state = PPPOE_SINIT;
811 	/* reset the packet header to broadcast */
812 	sp->neg->pkt->pkt_header.eh = eh_prototype;
813 	sp->neg->pkt->pkt_header.ph.code = PADI_CODE;
814 	uniqtag.hdr.tag_type = PTT_HOST_UNIQ;
815 	uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(uniqtag.data));
816 	uniqtag.data.pointer = sp;
817 	init_tags(sp);
818 	insert_tag(sp, &uniqtag.hdr);
819 	insert_tag(sp, &sp->neg->service.hdr);
820 	make_packet(sp);
821 	sendpacket(sp);
822 }
823 
824 /*
825  * Receive data, and do something with it.
826  * The caller will never free m or meta, so
827  * if we use up this data or abort we must free BOTH of these.
828  */
829 static int
830 ng_pppoe_rcvdata(hook_p hook, struct mbuf *m, meta_p meta,
831 		struct mbuf **ret_m, meta_p *ret_meta)
832 {
833 	node_p			node = hook->node;
834 	const priv_p		privp = node->private;
835 	sessp			sp = hook->private;
836 	struct pppoe_full_hdr	*wh;
837 	struct pppoe_hdr	*ph;
838 	int			error = 0;
839 	u_int16_t		session;
840 	u_int16_t		length;
841 	u_int8_t		code;
842 	struct pppoe_tag	*utag = NULL, *tag = NULL;
843 	hook_p 			sendhook;
844 	struct {
845 		struct pppoe_tag hdr;
846 		union	uniq	data;
847 	} uniqtag;
848 	negp			neg = NULL;
849 
850 AAA
851 	if (hook->private == &privp->debug_hook) {
852 		/*
853 		 * Data from the debug hook gets sent without modification
854 		 * straight to the ethernet.
855 		 */
856 		NG_SEND_DATA( error, privp->ethernet_hook, m, meta);
857 	 	privp->packets_out++;
858 	} else if (hook->private == &privp->ethernet_hook) {
859 		/*
860 		 * Incoming data.
861 		 * Dig out various fields from the packet.
862 		 * use them to decide where to send it.
863 		 */
864 
865  		privp->packets_in++;
866 		if( m->m_len < sizeof(*wh)) {
867 			m = m_pullup(m, sizeof(*wh)); /* Checks length */
868 			if (m == NULL) {
869 				printf("couldn't m_pullup\n");
870 				LEAVE(ENOBUFS);
871 			}
872 		}
873 		wh = mtod(m, struct pppoe_full_hdr *);
874 		ph = &wh->ph;
875 		session = ntohs(wh->ph.sid);
876 		length = ntohs(wh->ph.length);
877 		code = wh->ph.code;
878 		switch(wh->eh.ether_type) {
879 		case	ETHERTYPE_PPPOE_DISC:
880 			/*
881 			 * We need to try to make sure that the tag area
882 			 * is contiguous, or we could wander off the end
883 			 * of a buffer and make a mess.
884 			 * (Linux wouldn't have this problem).
885 			 */
886 /*XXX fix this mess */
887 
888 			if (m->m_pkthdr.len <= MHLEN) {
889 				if( m->m_len < m->m_pkthdr.len) {
890 					m = m_pullup(m, m->m_pkthdr.len);
891 					if (m == NULL) {
892 						printf("couldn't m_pullup\n");
893 						LEAVE(ENOBUFS);
894 					}
895 				}
896 			}
897 			if (m->m_len != m->m_pkthdr.len) {
898 				/*
899 				 * It's not all in one piece.
900 				 * We need to do extra work.
901 				 */
902 				printf("packet fragmented\n");
903 				LEAVE(EMSGSIZE);
904 			}
905 
906 			switch(code) {
907 			case	PADI_CODE:
908 				/*
909 				 * We are a server:
910 				 * Look for a hook with the required service
911 				 * and send the ENTIRE packet up there.
912 				 * It should come back to a new hook in
913 				 * PRIMED state. Look there for further
914 				 * processing.
915 				 */
916 				tag = get_tag(ph, PTT_SRV_NAME);
917 				if (tag == NULL) {
918 					printf("no service tag\n");
919 					LEAVE(ENETUNREACH);
920 				}
921 				sendhook = pppoe_match_svc(hook->node,
922 			    		tag->tag_data, ntohs(tag->tag_len));
923 				if (sendhook) {
924 					NG_SEND_DATA(error, sendhook, m, meta);
925 				} else {
926 					printf("no such service\n");
927 					LEAVE(ENETUNREACH);
928 				}
929 				break;
930 			case	PADO_CODE:
931 				/*
932 				 * We are a client:
933 				 * Use the host_uniq tag to find the
934 				 * hook this is in response to.
935 				 * Received #2, now send #3
936 				 * For now simply accept the first we receive.
937 				 */
938 				utag = get_tag(ph, PTT_HOST_UNIQ);
939 				if ((utag == NULL)
940 				|| (ntohs(utag->tag_len) != sizeof(sp))) {
941 					printf("no host unique field\n");
942 					LEAVE(ENETUNREACH);
943 				}
944 
945 				sendhook = pppoe_finduniq(node, utag);
946 				if (sendhook == NULL) {
947 					printf("no matching session\n");
948 					LEAVE(ENETUNREACH);
949 				}
950 
951 				/*
952 				 * Check the session is in the right state.
953 				 * It needs to be in PPPOE_SINIT.
954 				 */
955 				sp = sendhook->private;
956 				if (sp->state != PPPOE_SINIT) {
957 					printf("session in wrong state\n");
958 					LEAVE(ENETUNREACH);
959 				}
960 				neg = sp->neg;
961 				untimeout(pppoe_ticker, sendhook,
962 				    neg->timeout_handle);
963 
964 				/*
965 				 * This is the first time we hear
966 				 * from the server, so note it's
967 				 * unicast address, replacing the
968 				 * broadcast address .
969 				 */
970 				bcopy(wh->eh.ether_shost,
971 					neg->pkt->pkt_header.eh.ether_dhost,
972 					ETHER_ADDR_LEN);
973 				neg->timeout = 0;
974 				neg->pkt->pkt_header.ph.code = PADR_CODE;
975 				init_tags(sp);
976 				insert_tag(sp, utag);      /* Host Unique */
977 				if ((tag = get_tag(ph, PTT_AC_COOKIE)))
978 					insert_tag(sp, tag); /* return cookie */
979 				if ((tag = get_tag(ph, PTT_AC_NAME)))
980 					insert_tag(sp, tag); /* return it */
981 				insert_tag(sp, &neg->service.hdr); /* Service */
982 				scan_tags(sp, ph);
983 				make_packet(sp);
984 				sp->state = PPPOE_SREQ;
985 				sendpacket(sp);
986 				break;
987 			case	PADR_CODE:
988 
989 				/*
990 				 * We are a server:
991 				 * Use the ac_cookie tag to find the
992 				 * hook this is in response to.
993 				 */
994 				utag = get_tag(ph, PTT_AC_COOKIE);
995 				if ((utag == NULL)
996 				|| (ntohs(utag->tag_len) != sizeof(sp))) {
997 					LEAVE(ENETUNREACH);
998 				}
999 
1000 				sendhook = pppoe_finduniq(node, utag);
1001 				if (sendhook == NULL) {
1002 					LEAVE(ENETUNREACH);
1003 				}
1004 
1005 				/*
1006 				 * Check the session is in the right state.
1007 				 * It needs to be in PPPOE_SOFFER
1008 				 * or PPPOE_NEWCONNECTED. If the latter,
1009 				 * then this is a retry by the client.
1010 				 * so be nice, and resend.
1011 				 */
1012 				sp = sendhook->private;
1013 				if (sp->state == PPPOE_NEWCONNECTED) {
1014 					/*
1015 					 * Whoa! drop back to resend that
1016 					 * PADS packet.
1017 					 * We should still have a copy of it.
1018 					 */
1019 					sp->state = PPPOE_SOFFER;
1020 				}
1021 				if (sp->state != PPPOE_SOFFER) {
1022 					LEAVE (ENETUNREACH);
1023 					break;
1024 				}
1025 				neg = sp->neg;
1026 				untimeout(pppoe_ticker, sendhook,
1027 				    neg->timeout_handle);
1028 				neg->pkt->pkt_header.ph.code = PADS_CODE;
1029 				if (sp->Session_ID == 0)
1030 					neg->pkt->pkt_header.ph.sid =
1031 					    htons(sp->Session_ID
1032 						= get_new_sid(node));
1033 				neg->timeout = 0;
1034 				/*
1035 				 * start working out the tags to respond with.
1036 				 */
1037 				init_tags(sp);
1038 				insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1039 				if ((tag = get_tag(ph, PTT_SRV_NAME)))
1040 					insert_tag(sp, tag);/* return service */
1041 				if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1042 					insert_tag(sp, tag); /* return it */
1043 				insert_tag(sp, utag);	/* ac_cookie */
1044 				scan_tags(sp, ph);
1045 				make_packet(sp);
1046 				sp->state = PPPOE_NEWCONNECTED;
1047 				sendpacket(sp);
1048 				/*
1049 				 * Having sent the last Negotiation header,
1050 				 * Set up the stored packet header to
1051 				 * be correct for the actual session.
1052 				 * But keep the negotialtion stuff
1053 				 * around in case we need to resend this last
1054 				 * packet. We'll discard it when we move
1055 				 * from NEWCONNECTED to CONNECTED
1056 				 */
1057 				sp->pkt_hdr = neg->pkt->pkt_header;
1058 				sp->pkt_hdr.eh.ether_type
1059 						= ETHERTYPE_PPPOE_SESS;
1060 				sp->pkt_hdr.ph.code = 0;
1061 				pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1062 				break;
1063 			case	PADS_CODE:
1064 				/*
1065 				 * We are a client:
1066 				 * Use the host_uniq tag to find the
1067 				 * hook this is in response to.
1068 				 * take the session ID and store it away.
1069 				 * Also make sure the pre-made header is
1070 				 * correct and set us into Session mode.
1071 				 */
1072 				utag = get_tag(ph, PTT_HOST_UNIQ);
1073 				if ((utag == NULL)
1074 				|| (ntohs(utag->tag_len) != sizeof(sp))) {
1075 					LEAVE (ENETUNREACH);
1076 					break;
1077 				}
1078 				sendhook = pppoe_finduniq(node, utag);
1079 				if (sendhook == NULL) {
1080 					LEAVE(ENETUNREACH);
1081 				}
1082 
1083 				/*
1084 				 * Check the session is in the right state.
1085 				 * It needs to be in PPPOE_SREQ.
1086 				 */
1087 				sp = sendhook->private;
1088 				if (sp->state != PPPOE_SREQ) {
1089 					LEAVE(ENETUNREACH);
1090 				}
1091 				neg = sp->neg;
1092 				untimeout(pppoe_ticker, sendhook,
1093 				    neg->timeout_handle);
1094 				neg->pkt->pkt_header.ph.sid = wh->ph.sid;
1095 				sp->Session_ID = ntohs(wh->ph.sid);
1096 				neg->timeout = 0;
1097 				sp->state = PPPOE_CONNECTED;
1098 				/*
1099 				 * Now we have gone to Connected mode,
1100 				 * Free all resources needed for
1101 				 * negotiation.
1102 				 * Keep a copy of the header we will be using.
1103 				 */
1104 				sp->pkt_hdr = neg->pkt->pkt_header;
1105 				sp->pkt_hdr.eh.ether_type
1106 						= ETHERTYPE_PPPOE_SESS;
1107 				sp->pkt_hdr.ph.code = 0;
1108 				m_freem(neg->m);
1109 				FREE(sp->neg, M_NETGRAPH);
1110 				sp->neg = NULL;
1111 				pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1112 				break;
1113 			case	PADT_CODE:
1114 				/*
1115 				 * Send a 'close' message to the controlling
1116 				 * process (the one that set us up);
1117 				 * And then tear everything down.
1118 				 *
1119 				 * Find matching peer/session combination.
1120 				 */
1121 				sendhook = pppoe_findsession(node, wh);
1122 				NG_FREE_DATA(m, meta); /* no longer needed */
1123 				if (sendhook == NULL) {
1124 					LEAVE(ENETUNREACH);
1125 				}
1126 				/* send message to creator */
1127 				/* close hook */
1128 				if (sendhook) {
1129 					ng_destroy_hook(sendhook);
1130 				}
1131 				break;
1132 			default:
1133 				LEAVE(EPFNOSUPPORT);
1134 			}
1135 			break;
1136 		case	ETHERTYPE_PPPOE_SESS:
1137 			/*
1138 			 * find matching peer/session combination.
1139 			 */
1140 			sendhook = pppoe_findsession(node, wh);
1141 			if (sendhook == NULL) {
1142 				LEAVE (ENETUNREACH);
1143 				break;
1144 			}
1145 			sp = sendhook->private;
1146 			m_adj(m, sizeof(*wh));
1147 			if (m->m_pkthdr.len < length) {
1148 				/* Packet too short, dump it */
1149 				LEAVE(EMSGSIZE);
1150 			}
1151 
1152 			/* Also need to trim excess at the end */
1153 			if (m->m_pkthdr.len > length) {
1154 				m_adj(m, -((int)(m->m_pkthdr.len - length)));
1155 			}
1156 			if ( sp->state != PPPOE_CONNECTED) {
1157 				if (sp->state == PPPOE_NEWCONNECTED) {
1158 					sp->state = PPPOE_CONNECTED;
1159 					/*
1160 					 * Now we have gone to Connected mode,
1161 					 * Free all resources needed for
1162 					 * negotiation. Be paranoid about
1163 					 * whether there may be a timeout.
1164 					 */
1165 					m_freem(sp->neg->m);
1166 					untimeout(pppoe_ticker, sendhook,
1167 				    		sp->neg->timeout_handle);
1168 					FREE(sp->neg, M_NETGRAPH);
1169 					sp->neg = NULL;
1170 				} else {
1171 					LEAVE (ENETUNREACH);
1172 					break;
1173 				}
1174 			}
1175 			NG_SEND_DATA( error, sendhook, m, meta);
1176 			break;
1177 		default:
1178 			LEAVE(EPFNOSUPPORT);
1179 		}
1180 	} else {
1181 		/*
1182 		 * 	Not ethernet or debug hook..
1183 		 *
1184 		 * The packet has come in on a normal hook.
1185 		 * We need to find out what kind of hook,
1186 		 * So we can decide how to handle it.
1187 		 * Check the hook's state.
1188 		 */
1189 		sp = hook->private;
1190 		switch (sp->state) {
1191 		case	PPPOE_NEWCONNECTED:
1192 		case	PPPOE_CONNECTED: {
1193 			static const u_char addrctrl[] = { 0xff, 0x03 };
1194 			struct pppoe_full_hdr *wh;
1195 
1196 			/*
1197 			 * Remove PPP address and control fields, if any.
1198 			 * For example, ng_ppp(4) always sends LCP packets
1199 			 * with address and control fields as required by
1200 			 * generic PPP. PPPoE is an exception to the rule.
1201 			 */
1202 			if (m->m_pkthdr.len >= 2) {
1203 				if (m->m_len < 2 && !(m = m_pullup(m, 2)))
1204 					LEAVE(ENOBUFS);
1205 				if (bcmp(mtod(m, u_char *), addrctrl, 2) == 0)
1206 					m_adj(m, 2);
1207 			}
1208 			/*
1209 			 * Bang in a pre-made header, and set the length up
1210 			 * to be correct. Then send it to the ethernet driver.
1211 			 * But first correct the length.
1212 			 */
1213 			sp->pkt_hdr.ph.length = htons((short)(m->m_pkthdr.len));
1214 			M_PREPEND(m, sizeof(*wh), M_DONTWAIT);
1215 			if (m == NULL) {
1216 				LEAVE(ENOBUFS);
1217 			}
1218 			wh = mtod(m, struct pppoe_full_hdr *);
1219 			bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1220 			NG_SEND_DATA( error, privp->ethernet_hook, m, meta);
1221 			privp->packets_out++;
1222 			break;
1223 			}
1224 		case	PPPOE_PRIMED:
1225 			/*
1226 			 * A PADI packet is being returned by the application
1227 			 * that has set up this hook. This indicates that it
1228 			 * wants us to offer service.
1229 			 */
1230 			neg = sp->neg;
1231 			if (m->m_len < sizeof(*wh)) {
1232 				m = m_pullup(m, sizeof(*wh));
1233 				if (m == NULL) {
1234 					LEAVE(ENOBUFS);
1235 				}
1236 			}
1237 			wh = mtod(m, struct pppoe_full_hdr *);
1238 			ph = &wh->ph;
1239 			session = ntohs(wh->ph.sid);
1240 			length = ntohs(wh->ph.length);
1241 			code = wh->ph.code;
1242 			if ( code != PADI_CODE) {
1243 				LEAVE(EINVAL);
1244 			};
1245 			untimeout(pppoe_ticker, hook,
1246 				    neg->timeout_handle);
1247 
1248 			/*
1249 			 * This is the first time we hear
1250 			 * from the client, so note it's
1251 			 * unicast address, replacing the
1252 			 * broadcast address.
1253 			 */
1254 			bcopy(wh->eh.ether_shost,
1255 				neg->pkt->pkt_header.eh.ether_dhost,
1256 				ETHER_ADDR_LEN);
1257 			sp->state = PPPOE_SOFFER;
1258 			neg->timeout = 0;
1259 			neg->pkt->pkt_header.ph.code = PADO_CODE;
1260 
1261 			/*
1262 			 * start working out the tags to respond with.
1263 			 */
1264 			uniqtag.hdr.tag_type = PTT_AC_COOKIE;
1265 			uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(sp));
1266 			uniqtag.data.pointer = sp;
1267 			init_tags(sp);
1268 			insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1269 			if ((tag = get_tag(ph, PTT_SRV_NAME)))
1270 				insert_tag(sp, tag);	  /* return service */
1271 			if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1272 				insert_tag(sp, tag); /* returned hostunique */
1273 			insert_tag(sp, &uniqtag.hdr);
1274 			/* XXX maybe put the tag in the session store */
1275 			scan_tags(sp, ph);
1276 			make_packet(sp);
1277 			sendpacket(sp);
1278 			break;
1279 
1280 		/*
1281 		 * Packets coming from the hook make no sense
1282 		 * to sessions in these states. Throw them away.
1283 		 */
1284 		case	PPPOE_SINIT:
1285 		case	PPPOE_SREQ:
1286 		case	PPPOE_SOFFER:
1287 		case	PPPOE_SNONE:
1288 		case	PPPOE_LISTENING:
1289 		case	PPPOE_DEAD:
1290 		default:
1291 			LEAVE(ENETUNREACH);
1292 		}
1293 	}
1294 quit:
1295 	NG_FREE_DATA(m, meta);
1296 	return error;
1297 }
1298 
1299 /*
1300  * Do local shutdown processing..
1301  * If we are a persistant device, we might refuse to go away, and
1302  * we'd only remove our links and reset ourself.
1303  */
1304 static int
1305 ng_pppoe_rmnode(node_p node)
1306 {
1307 	const priv_p privdata = node->private;
1308 
1309 AAA
1310 	node->flags |= NG_INVALID;
1311 	ng_cutlinks(node);
1312 	ng_unname(node);
1313 	node->private = NULL;
1314 	ng_unref(privdata->node);
1315 	FREE(privdata, M_NETGRAPH);
1316 	return (0);
1317 }
1318 
1319 /*
1320  * This is called once we've already connected a new hook to the other node.
1321  * It gives us a chance to balk at the last minute.
1322  */
1323 static int
1324 ng_pppoe_connect(hook_p hook)
1325 {
1326 	/* be really amiable and just say "YUP that's OK by me! " */
1327 	return (0);
1328 }
1329 
1330 /*
1331  * Hook disconnection
1332  *
1333  * Clean up all dangling links and information about the session/hook.
1334  * For this type, removal of the last link destroys the node
1335  */
1336 static int
1337 ng_pppoe_disconnect(hook_p hook)
1338 {
1339 	node_p node = hook->node;
1340 	priv_p privp = node->private;
1341 	sessp	sp;
1342 	int 	hooks;
1343 
1344 AAA
1345 	hooks = node->numhooks; /* this one already not counted */
1346 	if (hook->private == &privp->debug_hook) {
1347 		privp->debug_hook = NULL;
1348 	} else if (hook->private == &privp->ethernet_hook) {
1349 		privp->ethernet_hook = NULL;
1350 		ng_rmnode(node);
1351 	} else {
1352 		sp = hook->private;
1353 		if (sp->state != PPPOE_SNONE ) {
1354 			pppoe_send_event(sp, NGM_PPPOE_CLOSE);
1355 		}
1356 		/*
1357 		 * According to the spec, if we are connected,
1358 		 * we should send a DISC packet if we are shutting down
1359 		 * a session.
1360 		 */
1361 		if ((privp->ethernet_hook)
1362 		&& ((sp->state == PPPOE_CONNECTED)
1363 		 || (sp->state == PPPOE_NEWCONNECTED))) {
1364 			struct mbuf *m;
1365 			struct pppoe_full_hdr *wh;
1366 			struct pppoe_tag *tag;
1367 			int	msglen = strlen(SIGNOFF);
1368 			void *dummy = NULL;
1369 			int error = 0;
1370 
1371 			/* revert the stored header to DISC/PADT mode */
1372 		 	wh = &sp->pkt_hdr;
1373 			wh->ph.code = PADT_CODE;
1374 			wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1375 
1376 			/* generate a packet of that type */
1377 			MGETHDR(m, M_DONTWAIT, MT_DATA);
1378 			if(m == NULL)
1379 				printf("pppoe: Session out of mbufs\n");
1380 			else {
1381 				m->m_pkthdr.rcvif = NULL;
1382 				m->m_pkthdr.len = m->m_len = sizeof(*wh);
1383 				bcopy((caddr_t)wh, mtod(m, caddr_t),
1384 				    sizeof(*wh));
1385 				/*
1386 				 * Add a General error message and adjust
1387 				 * sizes
1388 				 */
1389 				wh = mtod(m, struct pppoe_full_hdr *);
1390 				tag = wh->ph.tag;
1391 				tag->tag_type = PTT_GEN_ERR;
1392 				tag->tag_len = htons((u_int16_t)msglen);
1393 				strncpy(tag->tag_data, SIGNOFF, msglen);
1394 				m->m_pkthdr.len = (m->m_len += sizeof(*tag) +
1395 				    msglen);
1396 				wh->ph.length = htons(sizeof(*tag) + msglen);
1397 				NG_SEND_DATA(error, privp->ethernet_hook, m,
1398 				    dummy);
1399 			}
1400 		}
1401 		/*
1402 		 * As long as we have somewhere to store the timeout handle,
1403 		 * we may have a timeout pending.. get rid of it.
1404 		 */
1405 		if (sp->neg) {
1406 			untimeout(pppoe_ticker, hook, sp->neg->timeout_handle);
1407 			if (sp->neg->m)
1408 				m_freem(sp->neg->m);
1409 			FREE(sp->neg, M_NETGRAPH);
1410 		}
1411 		FREE(sp, M_NETGRAPH);
1412 		hook->private = NULL;
1413 		/* work out how many session hooks there are */
1414 		/* Node goes away on last session hook removal */
1415 		if (privp->ethernet_hook) hooks -= 1;
1416 		if (privp->debug_hook) hooks -= 1;
1417 	}
1418 	if (node->numhooks == 0)
1419 		ng_rmnode(node);
1420 	return (0);
1421 }
1422 
1423 /*
1424  * timeouts come here.
1425  */
1426 static void
1427 pppoe_ticker(void *arg)
1428 {
1429 	int s = splnet();
1430 	hook_p hook = arg;
1431 	sessp	sp = hook->private;
1432 	negp	neg = sp->neg;
1433 	int	error = 0;
1434 	struct mbuf *m0 = NULL;
1435 	priv_p privp = hook->node->private;
1436 	meta_p dummy = NULL;
1437 
1438 AAA
1439 	switch(sp->state) {
1440 		/*
1441 		 * resend the last packet, using an exponential backoff.
1442 		 * After a period of time, stop growing the backoff,
1443 		 * and either leave it, or revert to the start.
1444 		 */
1445 	case	PPPOE_SINIT:
1446 	case	PPPOE_SREQ:
1447 		/* timeouts on these produce resends */
1448 		m0 = m_copypacket(sp->neg->m, M_DONTWAIT);
1449 		NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1450 		neg->timeout_handle = timeout(pppoe_ticker,
1451 					hook, neg->timeout * hz);
1452 		if ((neg->timeout <<= 1) > PPPOE_TIMEOUT_LIMIT) {
1453 			if (sp->state == PPPOE_SREQ) {
1454 				/* revert to SINIT mode */
1455 				pppoe_start(sp);
1456 			} else {
1457 				neg->timeout = PPPOE_TIMEOUT_LIMIT;
1458 			}
1459 		}
1460 		break;
1461 	case	PPPOE_PRIMED:
1462 	case	PPPOE_SOFFER:
1463 		/* a timeout on these says "give up" */
1464 		ng_destroy_hook(hook);
1465 		break;
1466 	default:
1467 		/* timeouts have no meaning in other states */
1468 		printf("pppoe: unexpected timeout\n");
1469 	}
1470 	splx(s);
1471 }
1472 
1473 
1474 static void
1475 sendpacket(sessp sp)
1476 {
1477 	int	error = 0;
1478 	struct mbuf *m0 = NULL;
1479 	hook_p hook = sp->hook;
1480 	negp	neg = sp->neg;
1481 	priv_p	privp = hook->node->private;
1482 	meta_p dummy = NULL;
1483 
1484 AAA
1485 	switch(sp->state) {
1486 	case	PPPOE_LISTENING:
1487 	case	PPPOE_DEAD:
1488 	case	PPPOE_SNONE:
1489 	case	PPPOE_CONNECTED:
1490 		printf("pppoe: sendpacket: unexpected state\n");
1491 		break;
1492 
1493 	case	PPPOE_NEWCONNECTED:
1494 		/* send the PADS without a timeout - we're now connected */
1495 		m0 = m_copypacket(sp->neg->m, M_DONTWAIT);
1496 		NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1497 		break;
1498 
1499 	case	PPPOE_PRIMED:
1500 		/* No packet to send, but set up the timeout */
1501 		neg->timeout_handle = timeout(pppoe_ticker,
1502 					hook, PPPOE_OFFER_TIMEOUT * hz);
1503 		break;
1504 
1505 	case	PPPOE_SOFFER:
1506 		/*
1507 		 * send the offer but if they don't respond
1508 		 * in PPPOE_OFFER_TIMEOUT seconds, forget about it.
1509 		 */
1510 		m0 = m_copypacket(sp->neg->m, M_DONTWAIT);
1511 		NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1512 		neg->timeout_handle = timeout(pppoe_ticker,
1513 					hook, PPPOE_OFFER_TIMEOUT * hz);
1514 		break;
1515 
1516 	case	PPPOE_SINIT:
1517 	case	PPPOE_SREQ:
1518 		m0 = m_copypacket(sp->neg->m, M_DONTWAIT);
1519 		NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1520 		neg->timeout_handle = timeout(pppoe_ticker, hook,
1521 					(hz * PPPOE_INITIAL_TIMEOUT));
1522 		neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1523 		break;
1524 
1525 	default:
1526 		error = EINVAL;
1527 		printf("pppoe: timeout: bad state\n");
1528 	}
1529 	/* return (error); */
1530 }
1531 
1532 /*
1533  * Parse an incoming packet to see if any tags should be copied to the
1534  * output packet. Don't do any tags that have been handled in the main
1535  * state machine.
1536  */
1537 static struct pppoe_tag*
1538 scan_tags(sessp	sp, struct pppoe_hdr* ph)
1539 {
1540 	char *end = (char *)next_tag(ph);
1541 	char *ptn;
1542 	struct pppoe_tag *pt = &ph->tag[0];
1543 	/*
1544 	 * Keep processing tags while a tag header will still fit.
1545 	 */
1546 AAA
1547 	while((char*)(pt + 1) <= end) {
1548 		/*
1549 		 * If the tag data would go past the end of the packet, abort.
1550 		 */
1551 		ptn = (((char *)(pt + 1)) + ntohs(pt->tag_len));
1552 		if(ptn > end)
1553 			return NULL;
1554 
1555 		switch (pt->tag_type) {
1556 		case	PTT_RELAY_SID:
1557 			insert_tag(sp, pt);
1558 			break;
1559 		case	PTT_EOL:
1560 			return NULL;
1561 		case	PTT_SRV_NAME:
1562 		case	PTT_AC_NAME:
1563 		case	PTT_HOST_UNIQ:
1564 		case	PTT_AC_COOKIE:
1565 		case	PTT_VENDOR:
1566 		case	PTT_SRV_ERR:
1567 		case	PTT_SYS_ERR:
1568 		case	PTT_GEN_ERR:
1569 			break;
1570 		}
1571 		pt = (struct pppoe_tag*)ptn;
1572 	}
1573 	return NULL;
1574 }
1575 
1576 static	int
1577 pppoe_send_event(sessp sp, enum cmd cmdid)
1578 {
1579 	int error;
1580 	struct ng_mesg *msg;
1581 	struct ngpppoe_sts *sts;
1582 
1583 AAA
1584 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, cmdid,
1585 			sizeof(struct ngpppoe_sts), M_NOWAIT);
1586 	sts = (struct ngpppoe_sts *)msg->data;
1587 	strncpy(sts->hook, sp->hook->name, NG_HOOKLEN + 1);
1588 	error = ng_send_msg(sp->hook->node, msg, sp->creator, NULL);
1589 	return (error);
1590 }
1591