xref: /freebsd/sys/netgraph/ng_pppoe.c (revision 262e143bd46171a6415a5b28af260a5efa2a3db8)
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 #if 0
44 #define	DBG do { printf("ng_device: %s\n", __func__ ); } while (0)
45 #else
46 #define	DBG do {} while (0)
47 #endif
48 
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/kernel.h>
52 #include <sys/mbuf.h>
53 #include <sys/malloc.h>
54 #include <sys/errno.h>
55 #include <sys/syslog.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 #ifdef NG_SEPARATE_MALLOC
64 MALLOC_DEFINE(M_NETGRAPH_PPPOE, "netgraph_pppoe", "netgraph pppoe node");
65 #else
66 #define M_NETGRAPH_PPPOE M_NETGRAPH
67 #endif
68 
69 #define SIGNOFF "session closed"
70 #define OFFSETOF(s, e) ((char *)&((s *)0)->e - (char *)((s *)0))
71 
72 /*
73  * This section contains the netgraph method declarations for the
74  * pppoe node. These methods define the netgraph pppoe 'type'.
75  */
76 
77 static ng_constructor_t	ng_pppoe_constructor;
78 static ng_rcvmsg_t	ng_pppoe_rcvmsg;
79 static ng_shutdown_t	ng_pppoe_shutdown;
80 static ng_newhook_t	ng_pppoe_newhook;
81 static ng_rcvdata_t	ng_pppoe_rcvdata;
82 static ng_disconnect_t	ng_pppoe_disconnect;
83 
84 /* Parse type for struct ngpppoe_init_data */
85 static const struct ng_parse_struct_field ngpppoe_init_data_type_fields[]
86 	= NG_PPPOE_INIT_DATA_TYPE_INFO;
87 static const struct ng_parse_type ngpppoe_init_data_state_type = {
88 	&ng_parse_struct_type,
89 	&ngpppoe_init_data_type_fields
90 };
91 
92 /* Parse type for struct ngpppoe_sts */
93 static const struct ng_parse_struct_field ng_pppoe_sts_type_fields[]
94 	= NG_PPPOE_STS_TYPE_INFO;
95 static const struct ng_parse_type ng_pppoe_sts_state_type = {
96 	&ng_parse_struct_type,
97 	&ng_pppoe_sts_type_fields
98 };
99 
100 /* List of commands and how to convert arguments to/from ASCII */
101 static const struct ng_cmdlist ng_pppoe_cmds[] = {
102 	{
103 	  NGM_PPPOE_COOKIE,
104 	  NGM_PPPOE_CONNECT,
105 	  "pppoe_connect",
106 	  &ngpppoe_init_data_state_type,
107 	  NULL
108 	},
109 	{
110 	  NGM_PPPOE_COOKIE,
111 	  NGM_PPPOE_LISTEN,
112 	  "pppoe_listen",
113 	  &ngpppoe_init_data_state_type,
114 	  NULL
115 	},
116 	{
117 	  NGM_PPPOE_COOKIE,
118 	  NGM_PPPOE_OFFER,
119 	  "pppoe_offer",
120 	  &ngpppoe_init_data_state_type,
121 	  NULL
122 	},
123 	{
124 	  NGM_PPPOE_COOKIE,
125 	  NGM_PPPOE_SERVICE,
126 	  "pppoe_service",
127 	  &ngpppoe_init_data_state_type,
128 	  NULL
129 	},
130 	{
131 	  NGM_PPPOE_COOKIE,
132 	  NGM_PPPOE_SUCCESS,
133 	  "pppoe_success",
134 	  &ng_pppoe_sts_state_type,
135 	  NULL
136 	},
137 	{
138 	  NGM_PPPOE_COOKIE,
139 	  NGM_PPPOE_FAIL,
140 	  "pppoe_fail",
141 	  &ng_pppoe_sts_state_type,
142 	  NULL
143 	},
144 	{
145 	  NGM_PPPOE_COOKIE,
146 	  NGM_PPPOE_CLOSE,
147 	  "pppoe_close",
148 	  &ng_pppoe_sts_state_type,
149 	  NULL
150 	},
151 	{
152 	  NGM_PPPOE_COOKIE,
153 	  NGM_PPPOE_SETMODE,
154 	  "pppoe_setmode",
155 	  &ng_parse_string_type,
156 	  NULL
157 	},
158 	{
159 	  NGM_PPPOE_COOKIE,
160 	  NGM_PPPOE_GETMODE,
161 	  "pppoe_getmode",
162 	  NULL,
163 	  &ng_parse_string_type
164 	},
165 	{ 0 }
166 };
167 
168 /* Netgraph node type descriptor */
169 static struct ng_type typestruct = {
170 	.version =	NG_ABI_VERSION,
171 	.name =		NG_PPPOE_NODE_TYPE,
172 	.constructor =	ng_pppoe_constructor,
173 	.rcvmsg =	ng_pppoe_rcvmsg,
174 	.shutdown =	ng_pppoe_shutdown,
175 	.newhook =	ng_pppoe_newhook,
176 	.rcvdata =	ng_pppoe_rcvdata,
177 	.disconnect =	ng_pppoe_disconnect,
178 	.cmdlist =	ng_pppoe_cmds,
179 };
180 NETGRAPH_INIT(pppoe, &typestruct);
181 
182 /*
183  * States for the session state machine.
184  * These have no meaning if there is no hook attached yet.
185  */
186 enum state {
187     PPPOE_SNONE=0,	/* [both] Initial state */
188     PPPOE_LISTENING,	/* [Daemon] Listening for discover initiation pkt */
189     PPPOE_SINIT,	/* [Client] Sent discovery initiation */
190     PPPOE_PRIMED,	/* [Server] Awaiting PADI from daemon */
191     PPPOE_SOFFER,	/* [Server] Sent offer message  (got PADI)*/
192     PPPOE_SREQ,		/* [Client] Sent a Request */
193     PPPOE_NEWCONNECTED,	/* [Server] Connection established, No data received */
194     PPPOE_CONNECTED,	/* [Both] Connection established, Data received */
195     PPPOE_DEAD		/* [Both] */
196 };
197 
198 #define NUMTAGS 20 /* number of tags we are set up to work with */
199 
200 /*
201  * Information we store for each hook on each node for negotiating the
202  * session. The mbuf and cluster are freed once negotiation has completed.
203  * The whole negotiation block is then discarded.
204  */
205 
206 struct sess_neg {
207 	struct mbuf 		*m; /* holds cluster with last sent packet */
208 	union	packet		*pkt; /* points within the above cluster */
209 	struct callout		handle;   /* see timeout(9) */
210 	u_int			timeout; /* 0,1,2,4,8,16 etc. seconds */
211 	u_int			numtags;
212 	const struct pppoe_tag	*tags[NUMTAGS];
213 	u_int			service_len;
214 	u_int			ac_name_len;
215 
216 	struct datatag		service;
217 	struct datatag		ac_name;
218 };
219 typedef struct sess_neg *negp;
220 
221 /*
222  * Session information that is needed after connection.
223  */
224 struct sess_con {
225 	hook_p  		hook;
226 	u_int16_t		Session_ID;
227 	enum state		state;
228 	ng_ID_t			creator;		/* who to notify */
229 	struct pppoe_full_hdr	pkt_hdr;	/* used when connected */
230 	negp			neg;		/* used when negotiating */
231 	/*struct sess_con	*hash_next;*/	/* not yet used */
232 };
233 typedef struct sess_con *sessp;
234 
235 #define	NG_PPPOE_SESSION_NODE(sp) NG_HOOK_NODE(sp->hook)
236 
237 enum {
238 	PPPOE_STANDARD	= 1,	/* standard RFC2516 mode */
239 	PPPOE_NONSTANDARD,	/* 3Com proprietary mode */
240 };
241 
242 struct ng_pppoe_mode_t {
243 	u_int8_t        		id;
244 	const struct ether_header	*eh_prototype;
245 	const char      		*name;
246 };
247 
248 static const struct ether_header eh_standard =
249 	{{0xff,0xff,0xff,0xff,0xff,0xff},
250 	{0x00,0x00,0x00,0x00,0x00,0x00},
251 	ETHERTYPE_PPPOE_DISC};
252 
253 static const struct ether_header eh_3Com =
254 	{{0xff,0xff,0xff,0xff,0xff,0xff},
255 	{0x00,0x00,0x00,0x00,0x00,0x00},
256 	ETHERTYPE_PPPOE_STUPID_DISC};
257 
258 static const struct ng_pppoe_mode_t ng_pppoe_modes[] = {
259 	{ PPPOE_STANDARD,	&eh_standard,	NG_PPPOE_STANDARD },
260 	{ PPPOE_NONSTANDARD,	&eh_3Com,	NG_PPPOE_NONSTANDARD },
261 	{ 0, NULL},
262 };
263 
264 /*
265  * Information we store for each node
266  */
267 struct PPPOE {
268 	node_p		node;		/* back pointer to node */
269 	hook_p  	ethernet_hook;
270 	hook_p  	debug_hook;
271 	u_int   	packets_in;	/* packets in from ethernet */
272 	u_int   	packets_out;	/* packets out towards ethernet */
273 	u_int32_t	flags;
274 	const struct ng_pppoe_mode_t	*mode;	/* standard PPPoE or 3Com? */
275 	/*struct sess_con *buckets[HASH_SIZE];*/	/* not yet used */
276 };
277 typedef struct PPPOE *priv_p;
278 
279 union uniq {
280 	char bytes[sizeof(void *)];
281 	void * pointer;
282 	};
283 
284 #define	LEAVE(x) do { error = x; goto quit; } while(0)
285 static void	pppoe_start(sessp sp);
286 static void	sendpacket(sessp sp);
287 static void	pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2);
288 static const	struct pppoe_tag *scan_tags(sessp sp,
289 			const struct pppoe_hdr* ph);
290 static	int	pppoe_send_event(sessp sp, enum cmd cmdid);
291 
292 /*************************************************************************
293  * Some basic utilities  from the Linux version with author's permission.*
294  * Author:	Michal Ostrowski <mostrows@styx.uwaterloo.ca>		 *
295  ************************************************************************/
296 
297 /*
298  * Generate a new session id
299  * XXX find out the FreeBSD locking scheme.
300  */
301 static u_int16_t
302 get_new_sid(node_p node)
303 {
304 	static int pppoe_sid = 10;
305 	sessp sp;
306 	hook_p	hook;
307 	u_int16_t val;
308 	priv_p privp = NG_NODE_PRIVATE(node);
309 
310 	DBG;
311 restart:
312 	val = pppoe_sid++;
313 	/*
314 	 * Spec says 0xFFFF is reserved.
315 	 * Also don't use 0x0000
316 	 */
317 	if (val == 0xffff) {
318 		pppoe_sid = 20;
319 		goto restart;
320 	}
321 
322 	/* Check it isn't already in use */
323 	LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
324 		/* don't check special hooks */
325 		if ((NG_HOOK_PRIVATE(hook) == &privp->debug_hook)
326 		||  (NG_HOOK_PRIVATE(hook) == &privp->ethernet_hook))
327 			continue;
328 		sp = NG_HOOK_PRIVATE(hook);
329 		if (sp->Session_ID == val)
330 			goto restart;
331 	}
332 
333 	return val;
334 }
335 
336 
337 /*
338  * Return the location where the next tag can be put
339  */
340 static __inline const struct pppoe_tag*
341 next_tag(const struct pppoe_hdr* ph)
342 {
343 	return (const struct pppoe_tag*)(((const char*)&ph->tag[0])
344 	    + ntohs(ph->length));
345 }
346 
347 /*
348  * Look for a tag of a specific type
349  * Don't trust any length the other end says.
350  * but assume we already sanity checked ph->length.
351  */
352 static const struct pppoe_tag*
353 get_tag(const struct pppoe_hdr* ph, u_int16_t idx)
354 {
355 	const char *const end = (const char *)next_tag(ph);
356 	const char *ptn;
357 	const struct pppoe_tag *pt = &ph->tag[0];
358 	/*
359 	 * Keep processing tags while a tag header will still fit.
360 	 */
361 	DBG;
362 	while((const char*)(pt + 1) <= end) {
363 	    /*
364 	     * If the tag data would go past the end of the packet, abort.
365 	     */
366 	    ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
367 	    if(ptn > end)
368 		return NULL;
369 
370 	    if(pt->tag_type == idx)
371 		return pt;
372 
373 	    pt = (const struct pppoe_tag*)ptn;
374 	}
375 	return NULL;
376 }
377 
378 /**************************************************************************
379  * inlines to initialise or add tags to a session's tag list,
380  **************************************************************************/
381 /*
382  * Initialise the session's tag list
383  */
384 static void
385 init_tags(sessp sp)
386 {
387 	DBG;
388 	if(sp->neg == NULL) {
389 		printf("pppoe: asked to init NULL neg pointer\n");
390 		return;
391 	}
392 	sp->neg->numtags = 0;
393 }
394 
395 static void
396 insert_tag(sessp sp, const struct pppoe_tag *tp)
397 {
398 	int	i;
399 	negp neg;
400 
401 	DBG;
402 	if((neg = sp->neg) == NULL) {
403 		printf("pppoe: asked to use NULL neg pointer\n");
404 		return;
405 	}
406 	if ((i = neg->numtags++) < NUMTAGS) {
407 		neg->tags[i] = tp;
408 	} else {
409 		printf("pppoe: asked to add too many tags to packet\n");
410 		neg->numtags--;
411 	}
412 }
413 
414 /*
415  * Make up a packet, using the tags filled out for the session.
416  *
417  * Assume that the actual pppoe header and ethernet header
418  * are filled out externally to this routine.
419  * Also assume that neg->wh points to the correct
420  * location at the front of the buffer space.
421  */
422 static void
423 make_packet(sessp sp) {
424 	struct pppoe_full_hdr *wh = &sp->neg->pkt->pkt_header;
425 	const struct pppoe_tag **tag;
426 	char *dp;
427 	int count;
428 	int tlen;
429 	u_int16_t length = 0;
430 
431 	DBG;
432 	if ((sp->neg == NULL) || (sp->neg->m == NULL)) {
433 		printf("pppoe: make_packet called from wrong state\n");
434 	}
435 	dp = (char *)wh->ph.tag;
436 	for (count = 0, tag = sp->neg->tags;
437 	    ((count < sp->neg->numtags) && (count < NUMTAGS));
438 	    tag++, count++) {
439 		tlen = ntohs((*tag)->tag_len) + sizeof(**tag);
440 		if ((length + tlen) > (ETHER_MAX_LEN - 4 - sizeof(*wh))) {
441 			printf("pppoe: tags too long\n");
442 			sp->neg->numtags = count;
443 			break;	/* XXX chop off what's too long */
444 		}
445 		bcopy(*tag, (char *)dp, tlen);
446 		length += tlen;
447 		dp += tlen;
448 	}
449  	wh->ph.length = htons(length);
450 	sp->neg->m->m_len = length + sizeof(*wh);
451 	sp->neg->m->m_pkthdr.len = length + sizeof(*wh);
452 }
453 
454 /**************************************************************************
455  * Routine to match a service offered					  *
456  **************************************************************************/
457 /*
458  * Find a hook that has a service string that matches that
459  * we are seeking. for now use a simple string.
460  * In the future we may need something like regexp().
461  * for testing allow a null string to match 1st found and a null service
462  * to match all requests. Also make '*' do the same.
463  */
464 
465 #define NG_MATCH_EXACT	1
466 #define NG_MATCH_ANY	2
467 
468 static hook_p
469 pppoe_match_svc(node_p node, const char *svc_name, int svc_len, int match)
470 {
471 	sessp	sp	= NULL;
472 	negp	neg	= NULL;
473 	priv_p	privp	= NG_NODE_PRIVATE(node);
474 	hook_p	allhook	= NULL;
475 	hook_p	hook;
476 
477 	DBG;
478 	LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
479 
480 		/* skip any hook that is debug or ethernet */
481 		if ((NG_HOOK_PRIVATE(hook) == &privp->debug_hook)
482 		||  (NG_HOOK_PRIVATE(hook) == &privp->ethernet_hook))
483 			continue;
484 		sp = NG_HOOK_PRIVATE(hook);
485 
486 		/* Skip any sessions which are not in LISTEN mode. */
487 		if ( sp->state != PPPOE_LISTENING)
488 			continue;
489 
490 		neg = sp->neg;
491 
492 		/* Special case for a blank or "*" service name (wildcard) */
493 		if (match == NG_MATCH_ANY && neg->service_len == 1 &&
494 		    neg->service.data[0] == '*') {
495 			allhook = hook;
496 			continue;
497 		}
498 
499 		/* If the lengths don't match, that aint it. */
500 		if (neg->service_len != svc_len)
501 			continue;
502 
503 		/* An exact match? */
504 		if (svc_len == 0)
505 			break;
506 
507 		if (strncmp(svc_name, neg->service.data, svc_len) == 0)
508 			break;
509 	}
510 	return (hook ? hook : allhook);
511 }
512 /**************************************************************************
513  * Routine to find a particular session that matches an incoming packet	  *
514  **************************************************************************/
515 static hook_p
516 pppoe_findsession(node_p node, const struct pppoe_full_hdr *wh)
517 {
518 	sessp	sp = NULL;
519 	hook_p hook = NULL;
520 	priv_p	privp = NG_NODE_PRIVATE(node);
521 	u_int16_t	session = ntohs(wh->ph.sid);
522 
523 	/*
524 	 * find matching peer/session combination.
525 	 */
526 	DBG;
527 	LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
528 		/* don't check special hooks */
529 		if ((NG_HOOK_PRIVATE(hook) == &privp->debug_hook)
530 		||  (NG_HOOK_PRIVATE(hook) == &privp->ethernet_hook)) {
531 			continue;
532 		}
533 		sp = NG_HOOK_PRIVATE(hook);
534 		if ( ( (sp->state == PPPOE_CONNECTED)
535 		    || (sp->state == PPPOE_NEWCONNECTED) )
536 		&& (sp->Session_ID == session)
537 		&& (bcmp(sp->pkt_hdr.eh.ether_dhost,
538 		    wh->eh.ether_shost,
539 		    ETHER_ADDR_LEN)) == 0) {
540 			break;
541 		}
542 	}
543 	return (hook);
544 }
545 
546 static hook_p
547 pppoe_finduniq(node_p node, const struct pppoe_tag *tag)
548 {
549 	hook_p hook = NULL;
550 	priv_p	privp = NG_NODE_PRIVATE(node);
551 	union uniq		uniq;
552 
553 	DBG;
554 	bcopy(tag->tag_data, uniq.bytes, sizeof(void *));
555 	/* cycle through all known hooks */
556 	LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
557 		/* don't check special hooks */
558 		if ((NG_HOOK_PRIVATE(hook) == &privp->debug_hook)
559 		||  (NG_HOOK_PRIVATE(hook) == &privp->ethernet_hook))
560 			continue;
561 		if (uniq.pointer == NG_HOOK_PRIVATE(hook))
562 			break;
563 	}
564 	return (hook);
565 }
566 
567 /**************************************************************************
568  * start of Netgraph entrypoints					  *
569  **************************************************************************/
570 
571 /*
572  * Allocate the private data structure and the generic node
573  * and link them together.
574  *
575  * ng_make_node_common() returns with a generic node struct
576  * with a single reference for us.. we transfer it to the
577  * private structure.. when we free the private struct we must
578  * unref the node so it gets freed too.
579  */
580 static int
581 ng_pppoe_constructor(node_p node)
582 {
583 	priv_p privdata;
584 
585 	DBG;
586 	/* Initialize private descriptor */
587 	MALLOC(privdata, priv_p, sizeof(*privdata), M_NETGRAPH_PPPOE,
588 	    M_NOWAIT | M_ZERO);
589 	if (privdata == NULL)
590 		return (ENOMEM);
591 
592 	/* Link structs together; this counts as our one reference to *nodep */
593 	NG_NODE_SET_PRIVATE(node, privdata);
594 	privdata->node = node;
595 
596 	/* Initialize to standard mode (the first one in ng_pppoe_modes[]). */
597 	privdata->mode = &ng_pppoe_modes[0];
598 
599 	return (0);
600 }
601 
602 /*
603  * Give our ok for a hook to be added...
604  * point the hook's private info to the hook structure.
605  *
606  * The following hook names are special:
607  *  Ethernet:  the hook that should be connected to a NIC.
608  *  debug:	copies of data sent out here  (when I write the code).
609  * All other hook names need only be unique. (the framework checks this).
610  */
611 static int
612 ng_pppoe_newhook(node_p node, hook_p hook, const char *name)
613 {
614 	const priv_p privp = NG_NODE_PRIVATE(node);
615 	sessp sp;
616 
617 	DBG;
618 	if (strcmp(name, NG_PPPOE_HOOK_ETHERNET) == 0) {
619 		privp->ethernet_hook = hook;
620 		NG_HOOK_SET_PRIVATE(hook, &privp->ethernet_hook);
621 	} else if (strcmp(name, NG_PPPOE_HOOK_DEBUG) == 0) {
622 		privp->debug_hook = hook;
623 		NG_HOOK_SET_PRIVATE(hook, &privp->debug_hook);
624 	} else {
625 		/*
626 		 * Any other unique name is OK.
627 		 * The infrastructure has already checked that it's unique,
628 		 * so just allocate it and hook it in.
629 		 */
630 		MALLOC(sp, sessp, sizeof(*sp), M_NETGRAPH_PPPOE, M_NOWAIT | M_ZERO);
631 		if (sp == NULL) {
632 				return (ENOMEM);
633 		}
634 
635 		NG_HOOK_SET_PRIVATE(hook, sp);
636 		sp->hook = hook;
637 	}
638 	return(0);
639 }
640 
641 /*
642  * Get a netgraph control message.
643  * Check it is one we understand. If needed, send a response.
644  * We sometimes save the address for an async action later.
645  * Always free the message.
646  */
647 static int
648 ng_pppoe_rcvmsg(node_p node, item_p item, hook_p lasthook)
649 {
650 	priv_p privp = NG_NODE_PRIVATE(node);
651 	struct ngpppoe_init_data *ourmsg = NULL;
652 	struct ng_mesg *resp = NULL;
653 	int error = 0;
654 	hook_p hook = NULL;
655 	sessp sp = NULL;
656 	negp neg = NULL;
657 	struct ng_mesg *msg;
658 
659 	DBG;
660 	NGI_GET_MSG(item, msg);
661 	/* Deal with message according to cookie and command */
662 	switch (msg->header.typecookie) {
663 	case NGM_PPPOE_COOKIE:
664 		switch (msg->header.cmd) {
665 		case NGM_PPPOE_CONNECT:
666 		case NGM_PPPOE_LISTEN:
667 		case NGM_PPPOE_OFFER:
668 		case NGM_PPPOE_SERVICE:
669 			ourmsg = (struct ngpppoe_init_data *)msg->data;
670 			if (msg->header.arglen < sizeof(*ourmsg)) {
671 				printf("pppoe: init data too small\n");
672 				LEAVE(EMSGSIZE);
673 			}
674 			if (msg->header.arglen - sizeof(*ourmsg) >
675 			    PPPOE_SERVICE_NAME_SIZE) {
676 				printf("pppoe_rcvmsg: service name too big");
677 				LEAVE(EMSGSIZE);
678 			}
679 			if (msg->header.arglen - sizeof(*ourmsg) <
680 			    ourmsg->data_len) {
681 				printf("pppoe: init data has bad length,"
682 				    " %d should be %zd\n", ourmsg->data_len,
683 				    msg->header.arglen - sizeof (*ourmsg));
684 				LEAVE(EMSGSIZE);
685 			}
686 
687 			/* make sure strcmp will terminate safely */
688 			ourmsg->hook[sizeof(ourmsg->hook) - 1] = '\0';
689 
690 			/* cycle through all known hooks */
691 			LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
692 				if (NG_HOOK_NAME(hook)
693 				&& strcmp(NG_HOOK_NAME(hook), ourmsg->hook) == 0)
694 					break;
695 			}
696 			if (hook == NULL) {
697 				LEAVE(ENOENT);
698 			}
699 			if ((NG_HOOK_PRIVATE(hook) == &privp->debug_hook)
700 			||  (NG_HOOK_PRIVATE(hook) == &privp->ethernet_hook)) {
701 				LEAVE(EINVAL);
702 			}
703 			sp = NG_HOOK_PRIVATE(hook);
704 
705 			if (msg->header.cmd == NGM_PPPOE_LISTEN) {
706 				/*
707 				 * Ensure we aren't already listening for this
708 				 * service.
709 				 */
710 				if (pppoe_match_svc(node, ourmsg->data,
711 				    ourmsg->data_len, NG_MATCH_EXACT) != NULL) {
712 					LEAVE(EEXIST);
713 				}
714 			}
715 
716 			/*
717 			 * PPPOE_SERVICE advertisments are set up
718 			 * on sessions that are in PRIMED state.
719 			 */
720 			if (msg->header.cmd == NGM_PPPOE_SERVICE) {
721 				break;
722 			}
723 			if (sp->state != PPPOE_SNONE) {
724 				printf("pppoe: Session already active\n");
725 				LEAVE(EISCONN);
726 			}
727 
728 			/*
729 			 * set up prototype header
730 			 */
731 			MALLOC(neg, negp, sizeof(*neg), M_NETGRAPH_PPPOE,
732 			    M_NOWAIT | M_ZERO);
733 
734 			if (neg == NULL) {
735 				printf("pppoe: Session out of memory\n");
736 				LEAVE(ENOMEM);
737 			}
738 			MGETHDR(neg->m, M_DONTWAIT, MT_DATA);
739 			if(neg->m == NULL) {
740 				printf("pppoe: Session out of mbufs\n");
741 				FREE(neg, M_NETGRAPH_PPPOE);
742 				LEAVE(ENOBUFS);
743 			}
744 			neg->m->m_pkthdr.rcvif = NULL;
745 			MCLGET(neg->m, M_DONTWAIT);
746 			if ((neg->m->m_flags & M_EXT) == 0) {
747 				printf("pppoe: Session out of mcls\n");
748 				m_freem(neg->m);
749 				FREE(neg, M_NETGRAPH_PPPOE);
750 				LEAVE(ENOBUFS);
751 			}
752 			sp->neg = neg;
753 			ng_callout_init(&neg->handle);
754 			neg->m->m_len = sizeof(struct pppoe_full_hdr);
755 			neg->pkt = mtod(neg->m, union packet*);
756 			memcpy((void *)&neg->pkt->pkt_header.eh,
757 			    (const void *)privp->mode->eh_prototype,
758 			    sizeof(struct ether_header));
759 			neg->pkt->pkt_header.ph.ver = 0x1;
760 			neg->pkt->pkt_header.ph.type = 0x1;
761 			neg->pkt->pkt_header.ph.sid = 0x0000;
762 			neg->timeout = 0;
763 
764 			sp->creator = NGI_RETADDR(item);
765 		}
766 		switch (msg->header.cmd) {
767 		case NGM_PPPOE_GET_STATUS:
768 		    {
769 			struct ngpppoestat *stats;
770 
771 			NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT);
772 			if (!resp) {
773 				LEAVE(ENOMEM);
774 			}
775 			stats = (struct ngpppoestat *) resp->data;
776 			stats->packets_in = privp->packets_in;
777 			stats->packets_out = privp->packets_out;
778 			break;
779 		    }
780 		case NGM_PPPOE_CONNECT:
781 			/*
782 			 * Check the hook exists and is Uninitialised.
783 			 * Send a PADI request, and start the timeout logic.
784 			 * Store the originator of this message so we can send
785 			 * a success of fail message to them later.
786 			 * Move the session to SINIT
787 			 * Set up the session to the correct state and
788 			 * start it.
789 			 */
790 			neg->service.hdr.tag_type = PTT_SRV_NAME;
791 			neg->service.hdr.tag_len =
792 			    htons((u_int16_t)ourmsg->data_len);
793 			if (ourmsg->data_len)
794 				bcopy(ourmsg->data, neg->service.data,
795 				    ourmsg->data_len);
796 			neg->service_len = ourmsg->data_len;
797 			pppoe_start(sp);
798 			break;
799 		case NGM_PPPOE_LISTEN:
800 			/*
801 			 * Check the hook exists and is Uninitialised.
802 			 * Install the service matching string.
803 			 * Store the originator of this message so we can send
804 			 * a success of fail message to them later.
805 			 * Move the hook to 'LISTENING'
806 			 */
807 			neg->service.hdr.tag_type = PTT_SRV_NAME;
808 			neg->service.hdr.tag_len =
809 			    htons((u_int16_t)ourmsg->data_len);
810 
811 			if (ourmsg->data_len)
812 				bcopy(ourmsg->data, neg->service.data,
813 				    ourmsg->data_len);
814 			neg->service_len = ourmsg->data_len;
815 			neg->pkt->pkt_header.ph.code = PADT_CODE;
816 			/*
817 			 * wait for PADI packet coming from ethernet
818 			 */
819 			sp->state = PPPOE_LISTENING;
820 			break;
821 		case NGM_PPPOE_OFFER:
822 			/*
823 			 * Check the hook exists and is Uninitialised.
824 			 * Store the originator of this message so we can send
825 			 * a success of fail message to them later.
826 			 * Store the AC-Name given and go to PRIMED.
827 			 */
828 			neg->ac_name.hdr.tag_type = PTT_AC_NAME;
829 			neg->ac_name.hdr.tag_len =
830 			    htons((u_int16_t)ourmsg->data_len);
831 			if (ourmsg->data_len)
832 				bcopy(ourmsg->data, neg->ac_name.data,
833 				    ourmsg->data_len);
834 			neg->ac_name_len = ourmsg->data_len;
835 			neg->pkt->pkt_header.ph.code = PADO_CODE;
836 			/*
837 			 * Wait for PADI packet coming from hook
838 			 */
839 			sp->state = PPPOE_PRIMED;
840 			break;
841 		case NGM_PPPOE_SERVICE:
842 			/*
843 			 * Check the session is primed.
844 			 * for now just allow ONE service to be advertised.
845 			 * If you do it twice you just overwrite.
846 			 */
847 			if (sp->state != PPPOE_PRIMED) {
848 				printf("pppoe: Session not primed\n");
849 				LEAVE(EISCONN);
850 			}
851 			neg = sp->neg;
852 			neg->service.hdr.tag_type = PTT_SRV_NAME;
853 			neg->service.hdr.tag_len =
854 			    htons((u_int16_t)ourmsg->data_len);
855 
856 			if (ourmsg->data_len)
857 				bcopy(ourmsg->data, neg->service.data,
858 				    ourmsg->data_len);
859 			neg->service_len = ourmsg->data_len;
860 			break;
861 		case NGM_PPPOE_SETMODE:
862 		    {
863 			const struct ng_pppoe_mode_t *mode;
864 			char *s;
865 			size_t len;
866 
867 			if (msg->header.arglen == 0)
868 				LEAVE(EINVAL);
869 
870 			s = (char *)msg->data;
871 			len = msg->header.arglen - 1;
872 
873 			/* Search for matching mode string */
874 			for (mode = ng_pppoe_modes; mode->id != 0; mode++ )
875 				if ((strlen(mode->name) == len) &&
876 				    !strncmp(mode->name, s, len))
877 					break;	/* found */
878 
879 			if (mode->id != 0)
880 				privp->mode = mode;
881 			else
882 				LEAVE(EINVAL);
883 			break;
884 		    }
885 		case NGM_PPPOE_GETMODE:
886 			NG_MKRESPONSE(resp, msg, strlen(privp->mode->name) + 1,
887 			    M_NOWAIT);
888 			if (resp == NULL)
889 				LEAVE(ENOMEM);
890 			strlcpy((char *)resp->data, privp->mode->name,
891 			    strlen(privp->mode->name) + 1);
892 			break;
893 		default:
894 			LEAVE(EINVAL);
895 		}
896 		break;
897 	default:
898 		LEAVE(EINVAL);
899 	}
900 
901 	/* Take care of synchronous response, if any */
902 quit:
903 	NG_RESPOND_MSG(error, node, item, resp);
904 	/* Free the message and return */
905 	NG_FREE_MSG(msg);
906 	return(error);
907 }
908 
909 /*
910  * Start a client into the first state. A separate function because
911  * it can be needed if the negotiation times out.
912  */
913 static void
914 pppoe_start(sessp sp)
915 {
916 	priv_p	privp = NG_NODE_PRIVATE(NG_PPPOE_SESSION_NODE(sp));
917 	struct {
918 		struct pppoe_tag hdr;
919 		union	uniq	data;
920 	} __packed uniqtag;
921 
922 	/*
923 	 * kick the state machine into starting up
924 	 */
925 	DBG;
926 	sp->state = PPPOE_SINIT;
927 	/* Reset the packet header to broadcast. Since we are in a client
928 	 * mode use configured ethertype. */
929 	memcpy((void *)&sp->neg->pkt->pkt_header.eh,
930 	    (const void *)privp->mode->eh_prototype,
931 	    sizeof(struct ether_header));
932 	sp->neg->pkt->pkt_header.ph.code = PADI_CODE;
933 	uniqtag.hdr.tag_type = PTT_HOST_UNIQ;
934 	uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(uniqtag.data));
935 	uniqtag.data.pointer = sp;
936 	init_tags(sp);
937 	insert_tag(sp, &uniqtag.hdr);
938 	insert_tag(sp, &sp->neg->service.hdr);
939 	make_packet(sp);
940 	sendpacket(sp);
941 }
942 
943 static int
944 send_acname(sessp sp, const struct pppoe_tag *tag)
945 {
946 	int error, tlen;
947 	struct ng_mesg *msg;
948 	struct ngpppoe_sts *sts;
949 
950 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_ACNAME,
951 	    sizeof(struct ngpppoe_sts), M_NOWAIT);
952 	if (msg == NULL)
953 		return (ENOMEM);
954 
955 	sts = (struct ngpppoe_sts *)msg->data;
956 	tlen = min(NG_HOOKSIZ - 1, ntohs(tag->tag_len));
957 	strncpy(sts->hook, tag->tag_data, tlen);
958 	sts->hook[tlen] = '\0';
959 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
960 
961 	return (error);
962 }
963 
964 static int
965 send_sessionid(sessp sp)
966 {
967 	int error;
968 	struct ng_mesg *msg;
969 
970 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SESSIONID,
971 	    sizeof(u_int16_t), M_NOWAIT);
972 	if (msg == NULL)
973 		return (ENOMEM);
974 
975 	*(u_int16_t *)msg->data = sp->Session_ID;
976 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
977 
978 	return (error);
979 }
980 
981 /*
982  * Receive data, and do something with it.
983  * The caller will never free m, so if we use up this data
984  * or abort we must free it.
985  */
986 static int
987 ng_pppoe_rcvdata(hook_p hook, item_p item)
988 {
989 	node_p			node = NG_HOOK_NODE(hook);
990 	const priv_p		privp = NG_NODE_PRIVATE(node);
991 	sessp			sp = NG_HOOK_PRIVATE(hook);
992 	const struct pppoe_full_hdr *wh;
993 	const struct pppoe_hdr	*ph;
994 	int			error = 0;
995 	u_int16_t		session;
996 	u_int16_t		length;
997 	u_int8_t		code;
998 	const struct pppoe_tag	*utag = NULL, *tag = NULL;
999 	hook_p 			sendhook;
1000 	struct {
1001 		struct pppoe_tag hdr;
1002 		union	uniq	data;
1003 	} __packed uniqtag;
1004 	negp			neg = NULL;
1005 	struct mbuf		*m;
1006 
1007 	DBG;
1008 	NGI_GET_M(item, m);
1009 	if (NG_HOOK_PRIVATE(hook) == &privp->debug_hook) {
1010 		/*
1011 		 * Data from the debug hook gets sent without modification
1012 		 * straight to the ethernet.
1013 		 */
1014 		NG_FWD_ITEM_HOOK( error, item, privp->ethernet_hook);
1015 	 	privp->packets_out++;
1016 	} else if (NG_HOOK_PRIVATE(hook) == &privp->ethernet_hook) {
1017 		/*
1018 		 * Incoming data.
1019 		 * Dig out various fields from the packet.
1020 		 * use them to decide where to send it.
1021 		 */
1022 
1023  		privp->packets_in++;
1024 		if( m->m_len < sizeof(*wh)) {
1025 			m = m_pullup(m, sizeof(*wh)); /* Checks length */
1026 			if (m == NULL) {
1027 				printf("couldn't m_pullup\n");
1028 				LEAVE(ENOBUFS);
1029 			}
1030 		}
1031 		wh = mtod(m, struct pppoe_full_hdr *);
1032 		length = ntohs(wh->ph.length);
1033 		switch(wh->eh.ether_type) {
1034 		case	ETHERTYPE_PPPOE_STUPID_DISC: /* fall through */
1035 		case	ETHERTYPE_PPPOE_DISC:
1036 			/*
1037 			 * We need to try to make sure that the tag area
1038 			 * is contiguous, or we could wander off the end
1039 			 * of a buffer and make a mess.
1040 			 * (Linux wouldn't have this problem).
1041 			 */
1042 			if (m->m_pkthdr.len <= MHLEN) {
1043 				if( m->m_len < m->m_pkthdr.len) {
1044 					m = m_pullup(m, m->m_pkthdr.len);
1045 					if (m == NULL) {
1046 						printf("couldn't m_pullup\n");
1047 						LEAVE(ENOBUFS);
1048 					}
1049 				}
1050 			}
1051 			if (m->m_len != m->m_pkthdr.len) {
1052 				/*
1053 				 * It's not all in one piece.
1054 				 * We need to do extra work.
1055 				 * Put it into a cluster.
1056 				 */
1057 				struct mbuf *n;
1058 				n = m_dup(m, M_DONTWAIT);
1059 				m_freem(m);
1060 				m = n;
1061 				if (m) {
1062 					/* just check we got a cluster */
1063 					if (m->m_len != m->m_pkthdr.len) {
1064 						m_freem(m);
1065 						m = NULL;
1066 					}
1067 				}
1068 				if (m == NULL) {
1069 					printf("packet fragmented\n");
1070 					LEAVE(EMSGSIZE);
1071 				}
1072 			}
1073 			wh = mtod(m, struct pppoe_full_hdr *);
1074 			length = ntohs(wh->ph.length);
1075 			ph = &wh->ph;
1076 			session = ntohs(wh->ph.sid);
1077 			code = wh->ph.code;
1078 
1079 			switch(code) {
1080 			case	PADI_CODE:
1081 				/*
1082 				 * We are a server:
1083 				 * Look for a hook with the required service
1084 				 * and send the ENTIRE packet up there.
1085 				 * It should come back to a new hook in
1086 				 * PRIMED state. Look there for further
1087 				 * processing.
1088 				 */
1089 				tag = get_tag(ph, PTT_SRV_NAME);
1090 				if (tag == NULL) {
1091 					printf("no service tag\n");
1092 					LEAVE(ENETUNREACH);
1093 				}
1094 				sendhook = pppoe_match_svc(NG_HOOK_NODE(hook),
1095 			    		tag->tag_data, ntohs(tag->tag_len),
1096 					NG_MATCH_ANY);
1097 				if (sendhook) {
1098 					NG_FWD_NEW_DATA(error, item,
1099 								sendhook, m);
1100 				} else {
1101 					LEAVE(ENETUNREACH);
1102 				}
1103 				break;
1104 			case	PADO_CODE:
1105 				/*
1106 				 * We are a client:
1107 				 * Use the host_uniq tag to find the
1108 				 * hook this is in response to.
1109 				 * Received #2, now send #3
1110 				 * For now simply accept the first we receive.
1111 				 */
1112 				utag = get_tag(ph, PTT_HOST_UNIQ);
1113 				if ((utag == NULL)
1114 				|| (ntohs(utag->tag_len) != sizeof(sp))) {
1115 					printf("no host unique field\n");
1116 					LEAVE(ENETUNREACH);
1117 				}
1118 
1119 				sendhook = pppoe_finduniq(node, utag);
1120 				if (sendhook == NULL) {
1121 					printf("no matching session\n");
1122 					LEAVE(ENETUNREACH);
1123 				}
1124 
1125 				/*
1126 				 * Check the session is in the right state.
1127 				 * It needs to be in PPPOE_SINIT.
1128 				 */
1129 				sp = NG_HOOK_PRIVATE(sendhook);
1130 				if (sp->state != PPPOE_SINIT) {
1131 					printf("session in wrong state\n");
1132 					LEAVE(ENETUNREACH);
1133 				}
1134 				neg = sp->neg;
1135 				ng_uncallout(&neg->handle, node);
1136 
1137 				/*
1138 				 * This is the first time we hear
1139 				 * from the server, so note it's
1140 				 * unicast address, replacing the
1141 				 * broadcast address .
1142 				 */
1143 				bcopy(wh->eh.ether_shost,
1144 					neg->pkt->pkt_header.eh.ether_dhost,
1145 					ETHER_ADDR_LEN);
1146 				neg->timeout = 0;
1147 				neg->pkt->pkt_header.ph.code = PADR_CODE;
1148 				init_tags(sp);
1149 				insert_tag(sp, utag);      /* Host Unique */
1150 				if ((tag = get_tag(ph, PTT_AC_COOKIE)))
1151 					insert_tag(sp, tag); /* return cookie */
1152 				if ((tag = get_tag(ph, PTT_AC_NAME))) {
1153 					insert_tag(sp, tag); /* return it */
1154 					send_acname(sp, tag);
1155 				}
1156 				insert_tag(sp, &neg->service.hdr); /* Service */
1157 				scan_tags(sp, ph);
1158 				make_packet(sp);
1159 				sp->state = PPPOE_SREQ;
1160 				sendpacket(sp);
1161 				break;
1162 			case	PADR_CODE:
1163 
1164 				/*
1165 				 * We are a server:
1166 				 * Use the ac_cookie tag to find the
1167 				 * hook this is in response to.
1168 				 */
1169 				utag = get_tag(ph, PTT_AC_COOKIE);
1170 				if ((utag == NULL)
1171 				|| (ntohs(utag->tag_len) != sizeof(sp))) {
1172 					LEAVE(ENETUNREACH);
1173 				}
1174 
1175 				sendhook = pppoe_finduniq(node, utag);
1176 				if (sendhook == NULL) {
1177 					LEAVE(ENETUNREACH);
1178 				}
1179 
1180 				/*
1181 				 * Check the session is in the right state.
1182 				 * It needs to be in PPPOE_SOFFER
1183 				 * or PPPOE_NEWCONNECTED. If the latter,
1184 				 * then this is a retry by the client.
1185 				 * so be nice, and resend.
1186 				 */
1187 				sp = NG_HOOK_PRIVATE(sendhook);
1188 				if (sp->state == PPPOE_NEWCONNECTED) {
1189 					/*
1190 					 * Whoa! drop back to resend that
1191 					 * PADS packet.
1192 					 * We should still have a copy of it.
1193 					 */
1194 					sp->state = PPPOE_SOFFER;
1195 				}
1196 				if (sp->state != PPPOE_SOFFER) {
1197 					LEAVE (ENETUNREACH);
1198 					break;
1199 				}
1200 				neg = sp->neg;
1201 				ng_uncallout(&neg->handle, node);
1202 				neg->pkt->pkt_header.ph.code = PADS_CODE;
1203 				if (sp->Session_ID == 0)
1204 					neg->pkt->pkt_header.ph.sid =
1205 					    htons(sp->Session_ID
1206 						= get_new_sid(node));
1207 				send_sessionid(sp);
1208 				neg->timeout = 0;
1209 				/*
1210 				 * start working out the tags to respond with.
1211 				 */
1212 				init_tags(sp);
1213 				insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1214 				if ((tag = get_tag(ph, PTT_SRV_NAME)))
1215 					insert_tag(sp, tag);/* return service */
1216 				if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1217 					insert_tag(sp, tag); /* return it */
1218 				insert_tag(sp, utag);	/* ac_cookie */
1219 				scan_tags(sp, ph);
1220 				make_packet(sp);
1221 				sp->state = PPPOE_NEWCONNECTED;
1222 				sendpacket(sp);
1223 				/*
1224 				 * Having sent the last Negotiation header,
1225 				 * Set up the stored packet header to
1226 				 * be correct for the actual session.
1227 				 * But keep the negotialtion stuff
1228 				 * around in case we need to resend this last
1229 				 * packet. We'll discard it when we move
1230 				 * from NEWCONNECTED to CONNECTED
1231 				 */
1232 				sp->pkt_hdr = neg->pkt->pkt_header;
1233 				/* Configure ethertype depending on what
1234 				 * ethertype was used at discovery phase */
1235 				if (sp->pkt_hdr.eh.ether_type ==
1236 				    ETHERTYPE_PPPOE_STUPID_DISC)
1237 					sp->pkt_hdr.eh.ether_type
1238 						= ETHERTYPE_PPPOE_STUPID_SESS;
1239 				else
1240 					sp->pkt_hdr.eh.ether_type
1241 						= ETHERTYPE_PPPOE_SESS;
1242 				sp->pkt_hdr.ph.code = 0;
1243 				pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1244 				break;
1245 			case	PADS_CODE:
1246 				/*
1247 				 * We are a client:
1248 				 * Use the host_uniq tag to find the
1249 				 * hook this is in response to.
1250 				 * take the session ID and store it away.
1251 				 * Also make sure the pre-made header is
1252 				 * correct and set us into Session mode.
1253 				 */
1254 				utag = get_tag(ph, PTT_HOST_UNIQ);
1255 				if ((utag == NULL)
1256 				|| (ntohs(utag->tag_len) != sizeof(sp))) {
1257 					LEAVE (ENETUNREACH);
1258 					break;
1259 				}
1260 				sendhook = pppoe_finduniq(node, utag);
1261 				if (sendhook == NULL) {
1262 					LEAVE(ENETUNREACH);
1263 				}
1264 
1265 				/*
1266 				 * Check the session is in the right state.
1267 				 * It needs to be in PPPOE_SREQ.
1268 				 */
1269 				sp = NG_HOOK_PRIVATE(sendhook);
1270 				if (sp->state != PPPOE_SREQ) {
1271 					LEAVE(ENETUNREACH);
1272 				}
1273 				neg = sp->neg;
1274 				ng_uncallout(&neg->handle, node);
1275 				neg->pkt->pkt_header.ph.sid = wh->ph.sid;
1276 				sp->Session_ID = ntohs(wh->ph.sid);
1277 				send_sessionid(sp);
1278 				neg->timeout = 0;
1279 				sp->state = PPPOE_CONNECTED;
1280 				/*
1281 				 * Now we have gone to Connected mode,
1282 				 * Free all resources needed for
1283 				 * negotiation.
1284 				 * Keep a copy of the header we will be using.
1285 				 */
1286 				sp->pkt_hdr = neg->pkt->pkt_header;
1287 				if (privp->mode->id == PPPOE_NONSTANDARD)
1288 					sp->pkt_hdr.eh.ether_type
1289 						= ETHERTYPE_PPPOE_STUPID_SESS;
1290 				else
1291 					sp->pkt_hdr.eh.ether_type
1292 						= ETHERTYPE_PPPOE_SESS;
1293 				sp->pkt_hdr.ph.code = 0;
1294 				m_freem(neg->m);
1295 				FREE(sp->neg, M_NETGRAPH_PPPOE);
1296 				sp->neg = NULL;
1297 				pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1298 				break;
1299 			case	PADT_CODE:
1300 				/*
1301 				 * Send a 'close' message to the controlling
1302 				 * process (the one that set us up);
1303 				 * And then tear everything down.
1304 				 *
1305 				 * Find matching peer/session combination.
1306 				 */
1307 				sendhook = pppoe_findsession(node, wh);
1308 				if (sendhook == NULL) {
1309 					LEAVE(ENETUNREACH);
1310 				}
1311 				/* send message to creator */
1312 				/* close hook */
1313 				if (sendhook) {
1314 					ng_rmhook_self(sendhook);
1315 				}
1316 				break;
1317 			default:
1318 				LEAVE(EPFNOSUPPORT);
1319 			}
1320 			break;
1321 		case	ETHERTYPE_PPPOE_STUPID_SESS:
1322 		case	ETHERTYPE_PPPOE_SESS:
1323 			/*
1324 			 * find matching peer/session combination.
1325 			 */
1326 			sendhook = pppoe_findsession(node, wh);
1327 			if (sendhook == NULL) {
1328 				LEAVE (ENETUNREACH);
1329 				break;
1330 			}
1331 			sp = NG_HOOK_PRIVATE(sendhook);
1332 			m_adj(m, sizeof(*wh));
1333 			if (m->m_pkthdr.len < length) {
1334 				/* Packet too short, dump it */
1335 				LEAVE(EMSGSIZE);
1336 			}
1337 
1338 			/* Also need to trim excess at the end */
1339 			if (m->m_pkthdr.len > length) {
1340 				m_adj(m, -((int)(m->m_pkthdr.len - length)));
1341 			}
1342 			if ( sp->state != PPPOE_CONNECTED) {
1343 				if (sp->state == PPPOE_NEWCONNECTED) {
1344 					sp->state = PPPOE_CONNECTED;
1345 					/*
1346 					 * Now we have gone to Connected mode,
1347 					 * Free all resources needed for
1348 					 * negotiation. Be paranoid about
1349 					 * whether there may be a timeout.
1350 					 */
1351 					m_freem(sp->neg->m);
1352 					ng_uncallout(&sp->neg->handle, node);
1353 					FREE(sp->neg, M_NETGRAPH_PPPOE);
1354 					sp->neg = NULL;
1355 				} else {
1356 					LEAVE (ENETUNREACH);
1357 					break;
1358 				}
1359 			}
1360 			NG_FWD_NEW_DATA( error, item, sendhook, m);
1361 			break;
1362 		default:
1363 			LEAVE(EPFNOSUPPORT);
1364 		}
1365 	} else {
1366 		/*
1367 		 * 	Not ethernet or debug hook..
1368 		 *
1369 		 * The packet has come in on a normal hook.
1370 		 * We need to find out what kind of hook,
1371 		 * So we can decide how to handle it.
1372 		 * Check the hook's state.
1373 		 */
1374 		sp = NG_HOOK_PRIVATE(hook);
1375 		switch (sp->state) {
1376 		case	PPPOE_NEWCONNECTED:
1377 		case	PPPOE_CONNECTED: {
1378 			static const u_char addrctrl[] = { 0xff, 0x03 };
1379 			struct pppoe_full_hdr *wh;
1380 
1381 			/*
1382 			 * Remove PPP address and control fields, if any.
1383 			 * For example, ng_ppp(4) always sends LCP packets
1384 			 * with address and control fields as required by
1385 			 * generic PPP. PPPoE is an exception to the rule.
1386 			 */
1387 			if (m->m_pkthdr.len >= 2) {
1388 				if (m->m_len < 2 && !(m = m_pullup(m, 2)))
1389 					LEAVE(ENOBUFS);
1390 				if (bcmp(mtod(m, u_char *), addrctrl, 2) == 0)
1391 					m_adj(m, 2);
1392 			}
1393 			/*
1394 			 * Bang in a pre-made header, and set the length up
1395 			 * to be correct. Then send it to the ethernet driver.
1396 			 * But first correct the length.
1397 			 */
1398 			sp->pkt_hdr.ph.length = htons((short)(m->m_pkthdr.len));
1399 			M_PREPEND(m, sizeof(*wh), M_DONTWAIT);
1400 			if (m == NULL) {
1401 				LEAVE(ENOBUFS);
1402 			}
1403 			wh = mtod(m, struct pppoe_full_hdr *);
1404 			bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1405 			NG_FWD_NEW_DATA( error, item, privp->ethernet_hook, m);
1406 			privp->packets_out++;
1407 			break;
1408 			}
1409 		case	PPPOE_PRIMED:
1410 			/*
1411 			 * A PADI packet is being returned by the application
1412 			 * that has set up this hook. This indicates that it
1413 			 * wants us to offer service.
1414 			 */
1415 			neg = sp->neg;
1416 			if (m->m_len < sizeof(*wh)) {
1417 				m = m_pullup(m, sizeof(*wh));
1418 				if (m == NULL) {
1419 					LEAVE(ENOBUFS);
1420 				}
1421 			}
1422 			wh = mtod(m, struct pppoe_full_hdr *);
1423 			ph = &wh->ph;
1424 			session = ntohs(wh->ph.sid);
1425 			length = ntohs(wh->ph.length);
1426 			code = wh->ph.code;
1427 			/* Use peers mode in session */
1428 			neg->pkt->pkt_header.eh.ether_type = wh->eh.ether_type;
1429 			if ( code != PADI_CODE) {
1430 				LEAVE(EINVAL);
1431 			};
1432 			ng_uncallout(&neg->handle, node);
1433 
1434 			/*
1435 			 * This is the first time we hear
1436 			 * from the client, so note it's
1437 			 * unicast address, replacing the
1438 			 * broadcast address.
1439 			 */
1440 			bcopy(wh->eh.ether_shost,
1441 				neg->pkt->pkt_header.eh.ether_dhost,
1442 				ETHER_ADDR_LEN);
1443 			sp->state = PPPOE_SOFFER;
1444 			neg->timeout = 0;
1445 			neg->pkt->pkt_header.ph.code = PADO_CODE;
1446 
1447 			/*
1448 			 * start working out the tags to respond with.
1449 			 */
1450 			uniqtag.hdr.tag_type = PTT_AC_COOKIE;
1451 			uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(sp));
1452 			uniqtag.data.pointer = sp;
1453 			init_tags(sp);
1454 			insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1455 			if ((tag = get_tag(ph, PTT_SRV_NAME)))
1456 				insert_tag(sp, tag);	  /* return service */
1457 			/*
1458 			 * If we have a NULL service request
1459 			 * and have an extra service defined in this hook,
1460 			 * then also add a tag for the extra service.
1461 			 * XXX this is a hack. eventually we should be able
1462 			 * to support advertising many services, not just one
1463 			 */
1464 			if (((tag == NULL) || (tag->tag_len == 0))
1465 			&& (neg->service.hdr.tag_len != 0)) {
1466 				insert_tag(sp, &neg->service.hdr); /* SERVICE */
1467 			}
1468 			if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1469 				insert_tag(sp, tag); /* returned hostunique */
1470 			insert_tag(sp, &uniqtag.hdr);
1471 			scan_tags(sp, ph);
1472 			make_packet(sp);
1473 			sendpacket(sp);
1474 			break;
1475 
1476 		/*
1477 		 * Packets coming from the hook make no sense
1478 		 * to sessions in these states. Throw them away.
1479 		 */
1480 		case	PPPOE_SINIT:
1481 		case	PPPOE_SREQ:
1482 		case	PPPOE_SOFFER:
1483 		case	PPPOE_SNONE:
1484 		case	PPPOE_LISTENING:
1485 		case	PPPOE_DEAD:
1486 		default:
1487 			LEAVE(ENETUNREACH);
1488 		}
1489 	}
1490 quit:
1491 	if (item)
1492 		NG_FREE_ITEM(item);
1493 	NG_FREE_M(m);
1494 	return error;
1495 }
1496 
1497 /*
1498  * Do local shutdown processing..
1499  * If we are a persistant device, we might refuse to go away, and
1500  * we'd only remove our links and reset ourself.
1501  */
1502 static int
1503 ng_pppoe_shutdown(node_p node)
1504 {
1505 	const priv_p privdata = NG_NODE_PRIVATE(node);
1506 
1507 	DBG;
1508 	NG_NODE_SET_PRIVATE(node, NULL);
1509 	NG_NODE_UNREF(privdata->node);
1510 	FREE(privdata, M_NETGRAPH_PPPOE);
1511 	return (0);
1512 }
1513 
1514 /*
1515  * Hook disconnection
1516  *
1517  * Clean up all dangling links and information about the session/hook.
1518  * For this type, removal of the last link destroys the node
1519  */
1520 static int
1521 ng_pppoe_disconnect(hook_p hook)
1522 {
1523 	node_p node = NG_HOOK_NODE(hook);
1524 	priv_p privp = NG_NODE_PRIVATE(node);
1525 	sessp	sp;
1526 	int 	hooks;
1527 
1528 	DBG;
1529 	hooks = NG_NODE_NUMHOOKS(node); /* this one already not counted */
1530 	if (NG_HOOK_PRIVATE(hook) == &privp->debug_hook) {
1531 		privp->debug_hook = NULL;
1532 	} else if (NG_HOOK_PRIVATE(hook) == &privp->ethernet_hook) {
1533 		privp->ethernet_hook = NULL;
1534 		if (NG_NODE_IS_VALID(node))
1535 			ng_rmnode_self(node);
1536 	} else {
1537 		sp = NG_HOOK_PRIVATE(hook);
1538 		if (sp->state != PPPOE_SNONE ) {
1539 			pppoe_send_event(sp, NGM_PPPOE_CLOSE);
1540 		}
1541 		/*
1542 		 * According to the spec, if we are connected,
1543 		 * we should send a DISC packet if we are shutting down
1544 		 * a session.
1545 		 */
1546 		if ((privp->ethernet_hook)
1547 		&& ((sp->state == PPPOE_CONNECTED)
1548 		 || (sp->state == PPPOE_NEWCONNECTED))) {
1549 			struct mbuf *m;
1550 			struct pppoe_full_hdr *wh;
1551 			struct pppoe_tag *tag;
1552 			int	msglen = strlen(SIGNOFF);
1553 			int error = 0;
1554 
1555 			/* revert the stored header to DISC/PADT mode */
1556 		 	wh = &sp->pkt_hdr;
1557 			wh->ph.code = PADT_CODE;
1558 			/* Configure ethertype depending on what was used during
1559 			 * sessions stage. */
1560 			if (sp->pkt_hdr.eh.ether_type ==
1561 			    ETHERTYPE_PPPOE_STUPID_SESS)
1562 				wh->eh.ether_type = ETHERTYPE_PPPOE_STUPID_DISC;
1563 			else
1564 				wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1565 
1566 			/* generate a packet of that type */
1567 			MGETHDR(m, M_DONTWAIT, MT_DATA);
1568 			if(m == NULL)
1569 				printf("pppoe: Session out of mbufs\n");
1570 			else {
1571 				m->m_pkthdr.rcvif = NULL;
1572 				m->m_pkthdr.len = m->m_len = sizeof(*wh);
1573 				bcopy((caddr_t)wh, mtod(m, caddr_t),
1574 				    sizeof(*wh));
1575 				/*
1576 				 * Add a General error message and adjust
1577 				 * sizes
1578 				 */
1579 				wh = mtod(m, struct pppoe_full_hdr *);
1580 				tag = wh->ph.tag;
1581 				tag->tag_type = PTT_GEN_ERR;
1582 				tag->tag_len = htons((u_int16_t)msglen);
1583 				strncpy(tag->tag_data, SIGNOFF, msglen);
1584 				m->m_pkthdr.len = (m->m_len += sizeof(*tag) +
1585 				    msglen);
1586 				wh->ph.length = htons(sizeof(*tag) + msglen);
1587 				NG_SEND_DATA_ONLY(error,
1588 					privp->ethernet_hook, m);
1589 			}
1590 		}
1591 		/*
1592 		 * As long as we have somewhere to store the timeout handle,
1593 		 * we may have a timeout pending.. get rid of it.
1594 		 */
1595 		if (sp->neg) {
1596 			ng_uncallout(&sp->neg->handle, node);
1597 			if (sp->neg->m)
1598 				m_freem(sp->neg->m);
1599 			FREE(sp->neg, M_NETGRAPH_PPPOE);
1600 		}
1601 		FREE(sp, M_NETGRAPH_PPPOE);
1602 		NG_HOOK_SET_PRIVATE(hook, NULL);
1603 		/* work out how many session hooks there are */
1604 		/* Node goes away on last session hook removal */
1605 		if (privp->ethernet_hook) hooks -= 1;
1606 		if (privp->debug_hook) hooks -= 1;
1607 	}
1608 	if ((NG_NODE_NUMHOOKS(node) == 0)
1609 	&& (NG_NODE_IS_VALID(node)))
1610 		ng_rmnode_self(node);
1611 	return (0);
1612 }
1613 
1614 /*
1615  * timeouts come here.
1616  */
1617 static void
1618 pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2)
1619 {
1620 	sessp	sp = NG_HOOK_PRIVATE(hook);
1621 	negp	neg = sp->neg;
1622 	int	error = 0;
1623 	struct mbuf *m0 = NULL;
1624 	priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
1625 
1626 	DBG;
1627 	switch(sp->state) {
1628 		/*
1629 		 * resend the last packet, using an exponential backoff.
1630 		 * After a period of time, stop growing the backoff,
1631 		 * and either leave it, or revert to the start.
1632 		 */
1633 	case	PPPOE_SINIT:
1634 	case	PPPOE_SREQ:
1635 		/* timeouts on these produce resends */
1636 		m0 = m_copypacket(sp->neg->m, M_DONTWAIT);
1637 		NG_SEND_DATA_ONLY( error, privp->ethernet_hook, m0);
1638 		ng_callout(&neg->handle, node, hook, neg->timeout * hz,
1639 		    pppoe_ticker, NULL, 0);
1640 		if ((neg->timeout <<= 1) > PPPOE_TIMEOUT_LIMIT) {
1641 			if (sp->state == PPPOE_SREQ) {
1642 				/* revert to SINIT mode */
1643 				pppoe_start(sp);
1644 			} else {
1645 				neg->timeout = PPPOE_TIMEOUT_LIMIT;
1646 			}
1647 		}
1648 		break;
1649 	case	PPPOE_PRIMED:
1650 	case	PPPOE_SOFFER:
1651 		/* a timeout on these says "give up" */
1652 		ng_rmhook_self(hook);
1653 		break;
1654 	default:
1655 		/* timeouts have no meaning in other states */
1656 		printf("pppoe: unexpected timeout\n");
1657 	}
1658 }
1659 
1660 
1661 static void
1662 sendpacket(sessp sp)
1663 {
1664 	struct	mbuf *m0 = NULL;
1665 	hook_p	hook = sp->hook;
1666 	node_p	node = NG_HOOK_NODE(hook);
1667 	priv_p	privp = NG_NODE_PRIVATE(node);
1668 	negp	neg = sp->neg;
1669 	int	error = 0;
1670 
1671 	DBG;
1672 	switch(sp->state) {
1673 	case	PPPOE_LISTENING:
1674 	case	PPPOE_DEAD:
1675 	case	PPPOE_SNONE:
1676 	case	PPPOE_CONNECTED:
1677 		printf("pppoe: sendpacket: unexpected state\n");
1678 		break;
1679 
1680 	case	PPPOE_NEWCONNECTED:
1681 		/* send the PADS without a timeout - we're now connected */
1682 		m0 = m_copypacket(sp->neg->m, M_DONTWAIT);
1683 		NG_SEND_DATA_ONLY( error, privp->ethernet_hook, m0);
1684 		break;
1685 
1686 	case	PPPOE_PRIMED:
1687 		/* No packet to send, but set up the timeout */
1688 		ng_callout(&neg->handle, node, hook, PPPOE_OFFER_TIMEOUT * hz,
1689 		    pppoe_ticker, NULL, 0);
1690 		break;
1691 
1692 	case	PPPOE_SOFFER:
1693 		/*
1694 		 * send the offer but if they don't respond
1695 		 * in PPPOE_OFFER_TIMEOUT seconds, forget about it.
1696 		 */
1697 		m0 = m_copypacket(sp->neg->m, M_DONTWAIT);
1698 		NG_SEND_DATA_ONLY( error, privp->ethernet_hook, m0);
1699 		ng_callout(&neg->handle, node, hook, PPPOE_OFFER_TIMEOUT * hz,
1700 		    pppoe_ticker, NULL, 0);
1701 		break;
1702 
1703 	case	PPPOE_SINIT:
1704 	case	PPPOE_SREQ:
1705 		m0 = m_copypacket(sp->neg->m, M_DONTWAIT);
1706 		NG_SEND_DATA_ONLY( error, privp->ethernet_hook, m0);
1707 		ng_callout(&neg->handle, node, hook, PPPOE_INITIAL_TIMEOUT * hz,
1708 		    pppoe_ticker, NULL, 0);
1709 		neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1710 		break;
1711 
1712 	default:
1713 		error = EINVAL;
1714 		printf("pppoe: timeout: bad state\n");
1715 	}
1716 	/* return (error); */
1717 }
1718 
1719 /*
1720  * Parse an incoming packet to see if any tags should be copied to the
1721  * output packet. Don't do any tags that have been handled in the main
1722  * state machine.
1723  */
1724 static const struct pppoe_tag*
1725 scan_tags(sessp	sp, const struct pppoe_hdr* ph)
1726 {
1727 	const char *const end = (const char *)next_tag(ph);
1728 	const char *ptn;
1729 	const struct pppoe_tag *pt = &ph->tag[0];
1730 	/*
1731 	 * Keep processing tags while a tag header will still fit.
1732 	 */
1733 	DBG;
1734 	while((const char*)(pt + 1) <= end) {
1735 		/*
1736 		 * If the tag data would go past the end of the packet, abort.
1737 		 */
1738 		ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
1739 		if(ptn > end)
1740 			return NULL;
1741 
1742 		switch (pt->tag_type) {
1743 		case	PTT_RELAY_SID:
1744 			insert_tag(sp, pt);
1745 			break;
1746 		case	PTT_EOL:
1747 			return NULL;
1748 		case	PTT_SRV_NAME:
1749 		case	PTT_AC_NAME:
1750 		case	PTT_HOST_UNIQ:
1751 		case	PTT_AC_COOKIE:
1752 		case	PTT_VENDOR:
1753 		case	PTT_SRV_ERR:
1754 		case	PTT_SYS_ERR:
1755 		case	PTT_GEN_ERR:
1756 			break;
1757 		}
1758 		pt = (const struct pppoe_tag*)ptn;
1759 	}
1760 	return NULL;
1761 }
1762 
1763 static	int
1764 pppoe_send_event(sessp sp, enum cmd cmdid)
1765 {
1766 	int error;
1767 	struct ng_mesg *msg;
1768 	struct ngpppoe_sts *sts;
1769 
1770 	DBG;
1771 	NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, cmdid,
1772 			sizeof(struct ngpppoe_sts), M_NOWAIT);
1773 	if (msg == NULL)
1774 		return (ENOMEM);
1775 	sts = (struct ngpppoe_sts *)msg->data;
1776 	strncpy(sts->hook, NG_HOOK_NAME(sp->hook), NG_HOOKSIZ);
1777 	NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1778 	return (error);
1779 }
1780