kernel: Remove some unused variables in netgraph/netgraph7.
[dragonfly.git] / sys / netgraph / pppoe / ng_pppoe.c
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: src/sys/netgraph/ng_pppoe.c,v 1.23.2.17 2002/07/02 22:17:18 archie Exp $
40  * $Whistle: ng_pppoe.c,v 1.10 1999/11/01 09:24:52 julian Exp $
41  */
42 #if 0
43 #define AAA kprintf("pppoe: %s\n", __func__ );
44 #define BBB kprintf("-%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 <sys/sysctl.h>
57 #include <sys/syslog.h>
58 #include <sys/thread2.h>
59 #include <net/ethernet.h>
60
61 #include <netgraph/ng_message.h>
62 #include <netgraph/netgraph.h>
63 #include "ng_pppoe.h"
64
65 #define SIGNOFF "session closed"
66
67 /*
68  * This section contains the netgraph method declarations for the
69  * pppoe node. These methods define the netgraph pppoe 'type'.
70  */
71
72 static ng_constructor_t ng_pppoe_constructor;
73 static ng_rcvmsg_t      ng_pppoe_rcvmsg;
74 static ng_shutdown_t    ng_pppoe_rmnode;
75 static ng_newhook_t     ng_pppoe_newhook;
76 static ng_connect_t     ng_pppoe_connect;
77 static ng_rcvdata_t     ng_pppoe_rcvdata;
78 static ng_disconnect_t  ng_pppoe_disconnect;
79
80 /* Netgraph node type descriptor */
81 static struct ng_type typestruct = {
82         NG_VERSION,
83         NG_PPPOE_NODE_TYPE,
84         NULL,
85         ng_pppoe_constructor,
86         ng_pppoe_rcvmsg,
87         ng_pppoe_rmnode,
88         ng_pppoe_newhook,
89         NULL,
90         ng_pppoe_connect,
91         ng_pppoe_rcvdata,
92         ng_pppoe_rcvdata,
93         ng_pppoe_disconnect,
94         NULL
95 };
96 NETGRAPH_INIT(pppoe, &typestruct);
97
98 /*
99  * States for the session state machine.
100  * These have no meaning if there is no hook attached yet.
101  */
102 enum state {
103     PPPOE_SNONE=0,      /* [both] Initial state */
104     PPPOE_LISTENING,    /* [Daemon] Listening for discover initiation pkt */
105     PPPOE_SINIT,        /* [Client] Sent discovery initiation */
106     PPPOE_PRIMED,       /* [Server] Awaiting PADI from daemon */
107     PPPOE_SOFFER,       /* [Server] Sent offer message  (got PADI)*/
108     PPPOE_SREQ,         /* [Client] Sent a Request */
109     PPPOE_NEWCONNECTED, /* [Server] Connection established, No data received */
110     PPPOE_CONNECTED,    /* [Both] Connection established, Data received */
111     PPPOE_DEAD          /* [Both] */
112 };
113
114 #define NUMTAGS 20 /* number of tags we are set up to work with */
115
116 /*
117  * Information we store for each hook on each node for negotiating the 
118  * session. The mbuf and cluster are freed once negotiation has completed.
119  * The whole negotiation block is then discarded.
120  */
121
122 struct sess_neg {
123         struct mbuf             *m; /* holds cluster with last sent packet */
124         union   packet          *pkt; /* points within the above cluster */
125         struct callout          timeout_ch;
126         u_int                   timeout; /* 0,1,2,4,8,16 etc. seconds */
127         u_int                   numtags;
128         const struct pppoe_tag  *tags[NUMTAGS];
129         u_int                   service_len;
130         u_int                   ac_name_len;
131
132         struct datatag          service;
133         struct datatag          ac_name;
134 };
135 typedef struct sess_neg *negp;
136
137 /*
138  * Session information that is needed after connection.
139  */
140 struct sess_con {
141         hook_p                  hook;
142         u_int16_t               Session_ID;
143         enum state              state;
144         char                    creator[NG_NODESIZ]; /* who to notify */
145         struct pppoe_full_hdr   pkt_hdr;        /* used when connected */
146         negp                    neg;            /* used when negotiating */
147         /*struct sess_con       *hash_next;*/   /* not yet used */
148 };
149 typedef struct sess_con *sessp;
150
151 /*
152  * Information we store for each node
153  */
154 struct PPPOE {
155         node_p          node;           /* back pointer to node */
156         hook_p          ethernet_hook;
157         hook_p          debug_hook;
158         u_int           packets_in;     /* packets in from ethernet */
159         u_int           packets_out;    /* packets out towards ethernet */
160         u_int32_t       flags;
161         /*struct sess_con *buckets[HASH_SIZE];*/        /* not yet used */
162 };
163 typedef struct PPPOE *priv_p;
164
165 struct ether_header eh_prototype =
166         {{0xff,0xff,0xff,0xff,0xff,0xff},
167          {0x00,0x00,0x00,0x00,0x00,0x00},
168          ETHERTYPE_PPPOE_DISC};
169
170 #define PPPOE_KEEPSTANDARD      -1      /* never switch to nonstandard mode */
171 #define PPPOE_STANDARD          0       /* try standard mode (dangerous!) */
172 #define PPPOE_NONSTANDARD       1       /* just be in nonstandard mode */
173 static int pppoe_mode = PPPOE_KEEPSTANDARD;
174
175 static int
176 ngpppoe_set_ethertype(SYSCTL_HANDLER_ARGS)
177 {
178         int error;
179         int val;
180
181         val = pppoe_mode;
182         error = sysctl_handle_int(oidp, &val, sizeof(int), req);
183         if (error != 0 || req->newptr == NULL)
184                 return (error);
185         switch (val) {
186         case PPPOE_NONSTANDARD:
187                 pppoe_mode = PPPOE_NONSTANDARD;
188                 eh_prototype.ether_type = ETHERTYPE_PPPOE_STUPID_DISC;
189                 break;
190         case PPPOE_STANDARD:
191                 pppoe_mode = PPPOE_STANDARD;
192                 eh_prototype.ether_type = ETHERTYPE_PPPOE_DISC;
193                 break;
194         case PPPOE_KEEPSTANDARD:
195                 pppoe_mode = PPPOE_KEEPSTANDARD;
196                 eh_prototype.ether_type = ETHERTYPE_PPPOE_DISC;
197                 break;
198         default:
199                 return (EINVAL);
200         }
201         return (0);
202 }
203
204 SYSCTL_PROC(_net_graph, OID_AUTO, nonstandard_pppoe, CTLTYPE_INT | CTLFLAG_RW,
205     0, sizeof(int), ngpppoe_set_ethertype, "I", "nonstandard ethertype");
206
207 union uniq {
208         char bytes[sizeof(void *)];
209         void * pointer;
210         };
211
212 #define LEAVE(x) do { error = x; goto quit; } while(0)
213 static void     pppoe_start(sessp sp);
214 static void     sendpacket(sessp sp);
215 static void     pppoe_ticker(void *arg);
216 static const    struct pppoe_tag *scan_tags(sessp sp,
217                         const struct pppoe_hdr* ph);
218 static  int     pppoe_send_event(sessp sp, enum cmd cmdid);
219
220 /*************************************************************************
221  * Some basic utilities  from the Linux version with author's permission.*
222  * Author:      Michal Ostrowski <mostrows@styx.uwaterloo.ca>            *
223  ************************************************************************/
224
225 /*
226  * Generate a new session id
227  * XXX find out the FreeBSD locking scheme.
228  */
229 static u_int16_t
230 get_new_sid(node_p node)
231 {
232         static int pppoe_sid = 10;
233         sessp sp;
234         hook_p  hook;
235         u_int16_t val; 
236         priv_p privp = node->private;
237
238 AAA
239 restart:
240         val = pppoe_sid++;
241         /*
242          * Spec says 0xFFFF is reserved.
243          * Also don't use 0x0000
244          */
245         if (val == 0xffff) {
246                 pppoe_sid = 20;
247                 goto restart;
248         }
249
250         /* Check it isn't already in use */
251         LIST_FOREACH(hook, &node->hooks, hooks) {
252                 /* don't check special hooks */
253                 if ((hook->private == &privp->debug_hook)
254                 ||  (hook->private == &privp->ethernet_hook)) 
255                         continue;
256                 sp = hook->private;
257                 if (sp->Session_ID == val)
258                         goto restart;
259         }
260
261         return val;
262 }
263
264
265 /*
266  * Return the location where the next tag can be put 
267  */
268 static __inline const struct pppoe_tag*
269 next_tag(const struct pppoe_hdr* ph)
270 {
271         return (const struct pppoe_tag*)(((const char*)&ph->tag[0])
272             + ntohs(ph->length));
273 }
274
275 /*
276  * Look for a tag of a specific type
277  * Don't trust any length the other end says.
278  * but assume we already sanity checked ph->length.
279  */
280 static const struct pppoe_tag*
281 get_tag(const struct pppoe_hdr* ph, u_int16_t idx)
282 {
283         const char *const end = (const char *)next_tag(ph);
284         const char *ptn;
285         const struct pppoe_tag *pt = &ph->tag[0];
286         /*
287          * Keep processing tags while a tag header will still fit.
288          */
289 AAA
290         while((const char*)(pt + 1) <= end) {
291             /*
292              * If the tag data would go past the end of the packet, abort.
293              */
294             ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
295             if(ptn > end)
296                 return NULL;
297
298             if(pt->tag_type == idx)
299                 return pt;
300
301             pt = (const struct pppoe_tag*)ptn;
302         }
303         return NULL;
304 }
305
306 /**************************************************************************
307  * inlines to initialise or add tags to a session's tag list,
308  **************************************************************************/
309 /*
310  * Initialise the session's tag list
311  */
312 static void
313 init_tags(sessp sp)
314 {
315 AAA
316         if(sp->neg == NULL) {
317                 kprintf("pppoe: asked to init NULL neg pointer\n");
318                 return;
319         }
320         sp->neg->numtags = 0;
321 }
322
323 static void
324 insert_tag(sessp sp, const struct pppoe_tag *tp)
325 {
326         int     i;
327         negp neg;
328
329 AAA
330         if((neg = sp->neg) == NULL) {
331                 kprintf("pppoe: asked to use NULL neg pointer\n");
332                 return;
333         }
334         if ((i = neg->numtags++) < NUMTAGS) {
335                 neg->tags[i] = tp;
336         } else {
337                 kprintf("pppoe: asked to add too many tags to packet\n");
338                 neg->numtags--;
339         }
340 }
341
342 /*
343  * Make up a packet, using the tags filled out for the session.
344  *
345  * Assume that the actual pppoe header and ethernet header 
346  * are filled out externally to this routine.
347  * Also assume that neg->wh points to the correct 
348  * location at the front of the buffer space.
349  */
350 static void
351 make_packet(sessp sp) {
352         struct pppoe_full_hdr *wh = &sp->neg->pkt->pkt_header;
353         const struct pppoe_tag **tag;
354         char *dp;
355         int count;
356         int tlen;
357         u_int16_t length = 0;
358
359 AAA
360         if ((sp->neg == NULL) || (sp->neg->m == NULL)) {
361                 kprintf("pppoe: make_packet called from wrong state\n");
362         }
363         dp = (char *)wh->ph.tag;
364         for (count = 0, tag = sp->neg->tags;
365             ((count < sp->neg->numtags) && (count < NUMTAGS)); 
366             tag++, count++) {
367                 tlen = ntohs((*tag)->tag_len) + sizeof(**tag);
368                 if ((length + tlen) > (ETHER_MAX_LEN - 4 - sizeof(*wh))) {
369                         kprintf("pppoe: tags too long\n");
370                         sp->neg->numtags = count;
371                         break;  /* XXX chop off what's too long */
372                 }
373                 bcopy(*tag, dp, tlen);
374                 length += tlen;
375                 dp += tlen;
376         }
377         wh->ph.length = htons(length);
378         sp->neg->m->m_len = length + sizeof(*wh);
379         sp->neg->m->m_pkthdr.len = length + sizeof(*wh);
380 }
381
382 /**************************************************************************
383  * Routine to match a service offered                                     *
384  **************************************************************************/
385 /* 
386  * Find a hook that has a service string that matches that
387  * we are seeking. for now use a simple string.
388  * In the future we may need something like regexp().
389  * for testing allow a null string to match 1st found and a null service
390  * to match all requests. Also make '*' do the same.
391  */
392
393 #define NG_MATCH_EXACT  1
394 #define NG_MATCH_ANY    2
395
396 static hook_p
397 pppoe_match_svc(node_p node, const char *svc_name, int svc_len, int match)
398 {
399         sessp   sp      = NULL;
400         negp    neg     = NULL;
401         priv_p  privp   = node->private;
402         hook_p  allhook = NULL;
403         hook_p  hook;
404
405 AAA
406         LIST_FOREACH(hook, &node->hooks, hooks) {
407
408                 /* skip any hook that is debug or ethernet */
409                 if ((hook->private == &privp->debug_hook)
410                 ||  (hook->private == &privp->ethernet_hook))
411                         continue;
412                 sp = hook->private;
413
414                 /* Skip any sessions which are not in LISTEN mode. */
415                 if ( sp->state != PPPOE_LISTENING)
416                         continue;
417
418                 neg = sp->neg;
419
420                 /* Special case for a blank or "*" service name (wildcard) */
421                 if (match == NG_MATCH_ANY && neg->service_len == 1 &&
422                     neg->service.data[0] == '*') {
423                         allhook = hook;
424                         continue;
425                 }
426
427                 /* If the lengths don't match, that aint it. */
428                 if (neg->service_len != svc_len)
429                         continue;
430
431                 /* An exact match? */
432                 if (svc_len == 0)
433                         break;
434
435                 if (strncmp(svc_name, neg->service.data, svc_len) == 0)
436                         break;
437         }
438         return (hook ? hook : allhook);
439 }
440 /**************************************************************************
441  * Routine to find a particular session that matches an incoming packet   *
442  **************************************************************************/
443 static hook_p
444 pppoe_findsession(node_p node, const struct pppoe_full_hdr *wh)
445 {
446         sessp   sp = NULL;
447         hook_p hook = NULL;
448         priv_p  privp = node->private;
449         u_int16_t       session = ntohs(wh->ph.sid);
450
451         /*
452          * find matching peer/session combination.
453          */
454 AAA
455         LIST_FOREACH(hook, &node->hooks, hooks) {
456                 /* don't check special hooks */
457                 if ((hook->private == &privp->debug_hook)
458                 ||  (hook->private == &privp->ethernet_hook)) {
459                         continue;
460                 }
461                 sp = hook->private;
462                 if ( ( (sp->state == PPPOE_CONNECTED)
463                     || (sp->state == PPPOE_NEWCONNECTED) )
464                 && (sp->Session_ID == session)
465                 && (bcmp(sp->pkt_hdr.eh.ether_dhost,
466                     wh->eh.ether_shost,
467                     ETHER_ADDR_LEN)) == 0) {
468                         break;
469                 }
470         }
471         return (hook);
472 }
473
474 static hook_p
475 pppoe_finduniq(node_p node, const struct pppoe_tag *tag)
476 {
477         hook_p hook = NULL;
478         priv_p  privp = node->private;
479         union uniq              uniq;
480
481 AAA
482         bcopy(tag->tag_data, uniq.bytes, sizeof(void *));
483         /* cycle through all known hooks */
484         LIST_FOREACH(hook, &node->hooks, hooks) {
485                 /* don't check special hooks */
486                 if ((hook->private == &privp->debug_hook)
487                 ||  (hook->private == &privp->ethernet_hook)) 
488                         continue;
489                 if (uniq.pointer == hook->private)
490                         break;
491         }
492         return (hook);
493 }
494
495 /**************************************************************************
496  * start of Netgraph entrypoints                                          *
497  **************************************************************************/
498
499 /*
500  * Allocate the private data structure and the generic node
501  * and link them together.
502  *
503  * ng_make_node_common() returns with a generic node struct
504  * with a single reference for us.. we transfer it to the
505  * private structure.. when we free the private struct we must
506  * unref the node so it gets freed too.
507  */
508 static int
509 ng_pppoe_constructor(node_p *nodep)
510 {
511         priv_p privdata;
512         int error;
513
514 AAA
515         /* Initialize private descriptor */
516         privdata = kmalloc(sizeof(*privdata), M_NETGRAPH, M_NOWAIT | M_ZERO);
517         if (privdata == NULL)
518                 return (ENOMEM);
519
520         /* Call the 'generic' (ie, superclass) node constructor */
521         if ((error = ng_make_node_common(&typestruct, nodep))) {
522                 kfree(privdata, M_NETGRAPH);
523                 return (error);
524         }
525
526         /* Link structs together; this counts as our one reference to *nodep */
527         (*nodep)->private = privdata;
528         privdata->node = *nodep;
529         return (0);
530 }
531
532 /*
533  * Give our ok for a hook to be added...
534  * point the hook's private info to the hook structure.
535  *
536  * The following hook names are special:
537  *  Ethernet:  the hook that should be connected to a NIC.
538  *  debug:      copies of data sent out here  (when I write the code).
539  * All other hook names need only be unique. (the framework checks this).
540  */
541 static int
542 ng_pppoe_newhook(node_p node, hook_p hook, const char *name)
543 {
544         const priv_p privp = node->private;
545         sessp sp;
546
547 AAA
548         if (strcmp(name, NG_PPPOE_HOOK_ETHERNET) == 0) {
549                 privp->ethernet_hook = hook;
550                 hook->private = &privp->ethernet_hook;
551         } else if (strcmp(name, NG_PPPOE_HOOK_DEBUG) == 0) {
552                 privp->debug_hook = hook;
553                 hook->private = &privp->debug_hook;
554         } else {
555                 /*
556                  * Any other unique name is OK.
557                  * The infrastructure has already checked that it's unique,
558                  * so just allocate it and hook it in.
559                  */
560                 sp = kmalloc(sizeof(*sp), M_NETGRAPH, M_NOWAIT | M_ZERO);
561                 if (sp == NULL)
562                         return (ENOMEM);
563
564                 hook->private = sp;
565                 sp->hook = hook;
566         }
567         return(0);
568 }
569
570 /*
571  * Get a netgraph control message.
572  * Check it is one we understand. If needed, send a response.
573  * We sometimes save the address for an async action later.
574  * Always free the message.
575  */
576 static int
577 ng_pppoe_rcvmsg(node_p node,
578            struct ng_mesg *msg, const char *retaddr, struct ng_mesg **rptr)
579 {
580         priv_p privp = node->private;
581         struct ngpppoe_init_data *ourmsg = NULL;
582         struct ng_mesg *resp = NULL;
583         int error = 0;
584         hook_p hook = NULL;
585         sessp sp = NULL;
586         negp neg = NULL;
587
588 AAA
589         /* Deal with message according to cookie and command */
590         switch (msg->header.typecookie) {
591         case NGM_PPPOE_COOKIE: 
592                 switch (msg->header.cmd) {
593                 case NGM_PPPOE_CONNECT:
594                 case NGM_PPPOE_LISTEN: 
595                 case NGM_PPPOE_OFFER: 
596                 case NGM_PPPOE_SERVICE: 
597                         ourmsg = (struct ngpppoe_init_data *)msg->data;
598                         if (( sizeof(*ourmsg) > msg->header.arglen)
599                         || ((sizeof(*ourmsg) + ourmsg->data_len)
600                             > msg->header.arglen)) {
601                                 kprintf("pppoe_rcvmsg: bad arg size");
602                                 LEAVE(EMSGSIZE);
603                         }
604                         if (ourmsg->data_len > PPPOE_SERVICE_NAME_SIZE) {
605                                 kprintf("pppoe: init data too long (%d)\n",
606                                                         ourmsg->data_len);
607                                 LEAVE(EMSGSIZE);
608                         }
609                         /* make sure strcmp will terminate safely */
610                         ourmsg->hook[sizeof(ourmsg->hook) - 1] = '\0';
611
612                         /* cycle through all known hooks */
613                         LIST_FOREACH(hook, &node->hooks, hooks) {
614                                 if (hook->name
615                                 && strcmp(hook->name, ourmsg->hook) == 0)
616                                         break;
617                         }
618                         if (hook == NULL) {
619                                 LEAVE(ENOENT);
620                         }
621                         if ((hook->private == &privp->debug_hook)
622                         ||  (hook->private == &privp->ethernet_hook)) {
623                                 LEAVE(EINVAL);
624                         }
625                         sp = hook->private;
626
627                         if (msg->header.cmd == NGM_PPPOE_LISTEN) {
628                                 /*
629                                  * Ensure we aren't already listening for this
630                                  * service.
631                                  */
632                                 if (pppoe_match_svc(node, ourmsg->data,
633                                     ourmsg->data_len, NG_MATCH_EXACT) != NULL) {
634                                         LEAVE(EEXIST);
635                                 }
636                         }
637
638                         /*
639                          * PPPOE_SERVICE advertisments are set up
640                          * on sessions that are in PRIMED state.
641                          */
642                         if (msg->header.cmd == NGM_PPPOE_SERVICE) {
643                                 break;
644                         }
645                         if (sp->state != PPPOE_SNONE) {
646                                 kprintf("pppoe: Session already active\n");
647                                 LEAVE(EISCONN);
648                         }
649
650                         /*
651                          * set up prototype header
652                          */
653                         neg = kmalloc(sizeof(*neg), M_NETGRAPH,
654                                       M_NOWAIT | M_ZERO);
655
656                         if (neg == NULL) {
657                                 kprintf("pppoe: Session out of memory\n");
658                                 LEAVE(ENOMEM);
659                         }
660                         MGETHDR(neg->m, MB_DONTWAIT, MT_DATA);
661                         if(neg->m == NULL) {
662                                 kprintf("pppoe: Session out of mbufs\n");
663                                 kfree(neg, M_NETGRAPH);
664                                 LEAVE(ENOBUFS);
665                         }
666                         neg->m->m_pkthdr.rcvif = NULL;
667                         MCLGET(neg->m, MB_DONTWAIT);
668                         if ((neg->m->m_flags & M_EXT) == 0) {
669                                 kprintf("pppoe: Session out of mcls\n");
670                                 m_freem(neg->m);
671                                 kfree(neg, M_NETGRAPH);
672                                 LEAVE(ENOBUFS);
673                         }
674                         sp->neg = neg;
675                         callout_init(&neg->timeout_ch);
676                         neg->m->m_len = sizeof(struct pppoe_full_hdr);
677                         neg->pkt = mtod(neg->m, union packet*);
678                         neg->pkt->pkt_header.eh = eh_prototype;
679                         neg->pkt->pkt_header.ph.ver = 0x1;
680                         neg->pkt->pkt_header.ph.type = 0x1;
681                         neg->pkt->pkt_header.ph.sid = 0x0000;
682                         neg->timeout = 0;
683
684                         strlcpy(sp->creator, retaddr, NG_NODESIZ);
685                 }
686                 switch (msg->header.cmd) {
687                 case NGM_PPPOE_GET_STATUS:
688                     {
689                         struct ngpppoestat *stats;
690
691                         NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT);
692                         if (!resp) {
693                                 LEAVE(ENOMEM);
694                         }
695                         stats = (struct ngpppoestat *) resp->data;
696                         stats->packets_in = privp->packets_in;
697                         stats->packets_out = privp->packets_out;
698                         break;
699                     }
700                 case NGM_PPPOE_CONNECT:
701                         /*
702                          * Check the hook exists and is Uninitialised.
703                          * Send a PADI request, and start the timeout logic.
704                          * Store the originator of this message so we can send
705                          * a success of fail message to them later.
706                          * Move the session to SINIT
707                          * Set up the session to the correct state and
708                          * start it.
709                          */
710                         neg->service.hdr.tag_type = PTT_SRV_NAME;
711                         neg->service.hdr.tag_len =
712                                         htons((u_int16_t)ourmsg->data_len);
713                         if (ourmsg->data_len) {
714                                 bcopy(ourmsg->data,
715                                         neg->service.data, ourmsg->data_len);
716                         }
717                         neg->service_len = ourmsg->data_len;
718                         pppoe_start(sp);
719                         break;
720                 case NGM_PPPOE_LISTEN:
721                         /*
722                          * Check the hook exists and is Uninitialised.
723                          * Install the service matching string.
724                          * Store the originator of this message so we can send
725                          * a success of fail message to them later.
726                          * Move the hook to 'LISTENING'
727                          */
728                         neg->service.hdr.tag_type = PTT_SRV_NAME;
729                         neg->service.hdr.tag_len =
730                                         htons((u_int16_t)ourmsg->data_len);
731
732                         if (ourmsg->data_len) {
733                                 bcopy(ourmsg->data,
734                                         neg->service.data, ourmsg->data_len);
735                         }
736                         neg->service_len = ourmsg->data_len;
737                         neg->pkt->pkt_header.ph.code = PADT_CODE;
738                         /*
739                          * wait for PADI packet coming from ethernet
740                          */
741                         sp->state = PPPOE_LISTENING;
742                         break;
743                 case NGM_PPPOE_OFFER:
744                         /*
745                          * Check the hook exists and is Uninitialised.
746                          * Store the originator of this message so we can send
747                          * a success of fail message to them later.
748                          * Store the AC-Name given and go to PRIMED.
749                          */
750                         neg->ac_name.hdr.tag_type = PTT_AC_NAME;
751                         neg->ac_name.hdr.tag_len =
752                                         htons((u_int16_t)ourmsg->data_len);
753                         if (ourmsg->data_len) {
754                                 bcopy(ourmsg->data,
755                                         neg->ac_name.data, ourmsg->data_len);
756                         }
757                         neg->ac_name_len = ourmsg->data_len;
758                         neg->pkt->pkt_header.ph.code = PADO_CODE;
759                         /*
760                          * Wait for PADI packet coming from hook
761                          */
762                         sp->state = PPPOE_PRIMED;
763                         break;
764                 case NGM_PPPOE_SERVICE: 
765                         /* 
766                          * Check the session is primed.
767                          * for now just allow ONE service to be advertised.
768                          * If you do it twice you just overwrite.
769                          */
770                         if (sp->state != PPPOE_PRIMED) {
771                                 kprintf("pppoe: Session not primed\n");
772                                 LEAVE(EISCONN);
773                         }
774                         neg = sp->neg;
775                         neg->service.hdr.tag_type = PTT_SRV_NAME;
776                         neg->service.hdr.tag_len =
777                             htons((u_int16_t)ourmsg->data_len);
778
779                         if (ourmsg->data_len)
780                                 bcopy(ourmsg->data, neg->service.data,
781                                     ourmsg->data_len);
782                         neg->service_len = ourmsg->data_len;
783                         break;
784                 default:
785                         LEAVE(EINVAL);
786                 }
787                 break;
788         default:
789                 LEAVE(EINVAL);
790         }
791
792         /* Take care of synchronous response, if any */
793         if (rptr)
794                 *rptr = resp;
795         else if (resp)
796                 kfree(resp, M_NETGRAPH);
797
798         /* Free the message and return */
799 quit:
800         kfree(msg, M_NETGRAPH);
801         return(error);
802 }
803
804 /*
805  * Start a client into the first state. A separate function because
806  * it can be needed if the negotiation times out.
807  */
808 static void
809 pppoe_start(sessp sp)
810 {
811         struct {
812                 struct pppoe_tag hdr;
813                 union   uniq    data;
814         } __attribute ((packed)) uniqtag;
815
816         /* 
817          * kick the state machine into starting up
818          */
819 AAA
820         sp->state = PPPOE_SINIT;
821         /* reset the packet header to broadcast */
822         sp->neg->pkt->pkt_header.eh = eh_prototype;
823         sp->neg->pkt->pkt_header.ph.code = PADI_CODE;
824         uniqtag.hdr.tag_type = PTT_HOST_UNIQ;
825         uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(uniqtag.data));
826         uniqtag.data.pointer = sp;
827         init_tags(sp);
828         insert_tag(sp, &uniqtag.hdr);
829         insert_tag(sp, &sp->neg->service.hdr);
830         make_packet(sp);
831         sendpacket(sp);
832 }
833
834 static int
835 send_acname(sessp sp, const struct pppoe_tag *tag)
836 {
837         int error, tlen;
838         struct ng_mesg *msg;
839         struct ngpppoe_sts *sts;
840
841         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_ACNAME,
842             sizeof(struct ngpppoe_sts), M_NOWAIT);
843         if (msg == NULL)
844                 return (ENOMEM);
845
846         sts = (struct ngpppoe_sts *)msg->data;
847         tlen = min(NG_HOOKSIZ - 1, ntohs(tag->tag_len));
848         strncpy(sts->hook, tag->tag_data, tlen);
849         sts->hook[tlen] = '\0';
850         error = ng_send_msg(sp->hook->node, msg, sp->creator, NULL);
851
852         return (error);
853 }
854
855 static int
856 send_sessionid(sessp sp)
857 {
858         int error;
859         struct ng_mesg *msg;
860
861         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SESSIONID,
862             sizeof(u_int16_t), M_NOWAIT);
863         if (msg == NULL)
864                 return (ENOMEM);
865
866         *(u_int16_t *)msg->data = sp->Session_ID;
867         error = ng_send_msg(sp->hook->node, msg, sp->creator, NULL);
868
869         return (error);
870 }
871
872 /*
873  * Receive data, and do something with it.
874  * The caller will never free m or meta, so
875  * if we use up this data or abort we must free BOTH of these.
876  */
877 static int
878 ng_pppoe_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
879 {
880         node_p                  node = hook->node;
881         const priv_p            privp = node->private;
882         sessp                   sp = hook->private;
883         const struct pppoe_full_hdr *wh;
884         const struct pppoe_hdr  *ph;
885         int                     error = 0;
886         u_int16_t               length;
887         u_int8_t                code;
888         const struct pppoe_tag  *utag = NULL, *tag = NULL;
889         hook_p                  sendhook;
890         struct {
891                 struct pppoe_tag hdr;
892                 union   uniq    data;
893         } __attribute ((packed)) uniqtag;
894         negp                    neg = NULL;
895
896 AAA
897         if (hook->private == &privp->debug_hook) {
898                 /*
899                  * Data from the debug hook gets sent without modification
900                  * straight to the ethernet. 
901                  */
902                 NG_SEND_DATA( error, privp->ethernet_hook, m, meta);
903                 privp->packets_out++;
904         } else if (hook->private == &privp->ethernet_hook) {
905                 /*
906                  * Incoming data. 
907                  * Dig out various fields from the packet.
908                  * use them to decide where to send it.
909                  */
910                 
911                 privp->packets_in++;
912                 if( m->m_len < sizeof(*wh)) {
913                         m = m_pullup(m, sizeof(*wh)); /* Checks length */
914                         if (m == NULL) {
915                                 kprintf("couldn't m_pullup\n");
916                                 LEAVE(ENOBUFS);
917                         }
918                 }
919                 wh = mtod(m, struct pppoe_full_hdr *);
920                 ph = &wh->ph;
921                 length = ntohs(wh->ph.length);
922                 code = wh->ph.code; 
923                 switch(wh->eh.ether_type) {
924                 case    ETHERTYPE_PPPOE_STUPID_DISC:
925                         if (pppoe_mode == PPPOE_STANDARD) {
926                                 pppoe_mode = PPPOE_NONSTANDARD;
927                                 eh_prototype.ether_type =
928                                     ETHERTYPE_PPPOE_STUPID_DISC;
929                                 log(LOG_NOTICE,
930                                     "Switched to nonstandard PPPoE mode due to "
931                                     "packet from %*D\n",
932                                     ETHER_ADDR_LEN,
933                                     wh->eh.ether_shost, ":");
934                         } else if (pppoe_mode == PPPOE_KEEPSTANDARD)
935                                 log(LOG_NOTICE,
936                                     "Ignored nonstandard PPPoE packet "
937                                     "from %*D\n",
938                                     ETHER_ADDR_LEN,
939                                     wh->eh.ether_shost, ":");
940                         /* fall through */
941                 case    ETHERTYPE_PPPOE_DISC:
942                         /*
943                          * We need to try to make sure that the tag area
944                          * is contiguous, or we could wander off the end
945                          * of a buffer and make a mess. 
946                          * (Linux wouldn't have this problem).
947                          */
948 /*XXX fix this mess */
949                         
950                         if (m->m_pkthdr.len <= MHLEN) {
951                                 if( m->m_len < m->m_pkthdr.len) {
952                                         m = m_pullup(m, m->m_pkthdr.len);
953                                         if (m == NULL) {
954                                                 kprintf("couldn't m_pullup\n");
955                                                 LEAVE(ENOBUFS);
956                                         }
957                                 }
958                         }
959                         if (m->m_len != m->m_pkthdr.len) {
960                                 /*
961                                  * It's not all in one piece.
962                                  * We need to do extra work.
963                                  */
964                                 kprintf("packet fragmented\n");
965                                 LEAVE(EMSGSIZE);
966                         }
967
968                         switch(code) {
969                         case    PADI_CODE:
970                                 /*
971                                  * We are a server:
972                                  * Look for a hook with the required service
973                                  * and send the ENTIRE packet up there.
974                                  * It should come back to a new hook in 
975                                  * PRIMED state. Look there for further
976                                  * processing.
977                                  */
978                                 tag = get_tag(ph, PTT_SRV_NAME);
979                                 if (tag == NULL) {
980                                         kprintf("no service tag\n");
981                                         LEAVE(ENETUNREACH);
982                                 }
983                                 sendhook = pppoe_match_svc(hook->node,
984                                         tag->tag_data, ntohs(tag->tag_len),
985                                         NG_MATCH_ANY);
986                                 if (sendhook) {
987                                         NG_SEND_DATA(error, sendhook, m, meta);
988                                 } else {
989                                         LEAVE(ENETUNREACH);
990                                 }
991                                 break;
992                         case    PADO_CODE:
993                                 /*
994                                  * We are a client:
995                                  * Use the host_uniq tag to find the 
996                                  * hook this is in response to.
997                                  * Received #2, now send #3
998                                  * For now simply accept the first we receive.
999                                  */
1000                                 utag = get_tag(ph, PTT_HOST_UNIQ);
1001                                 if ((utag == NULL)
1002                                 || (ntohs(utag->tag_len) != sizeof(sp))) {
1003                                         kprintf("no host unique field\n");
1004                                         LEAVE(ENETUNREACH);
1005                                 }
1006
1007                                 sendhook = pppoe_finduniq(node, utag);
1008                                 if (sendhook == NULL) {
1009                                         kprintf("no matching session\n");
1010                                         LEAVE(ENETUNREACH);
1011                                 }
1012
1013                                 /*
1014                                  * Check the session is in the right state.
1015                                  * It needs to be in PPPOE_SINIT.
1016                                  */
1017                                 sp = sendhook->private;
1018                                 if (sp->state != PPPOE_SINIT) {
1019                                         kprintf("session in wrong state\n");
1020                                         LEAVE(ENETUNREACH);
1021                                 }
1022                                 neg = sp->neg;
1023                                 callout_stop(&neg->timeout_ch);
1024
1025                                 /*
1026                                  * This is the first time we hear
1027                                  * from the server, so note it's
1028                                  * unicast address, replacing the
1029                                  * broadcast address .
1030                                  */
1031                                 bcopy(wh->eh.ether_shost,
1032                                         neg->pkt->pkt_header.eh.ether_dhost,
1033                                         ETHER_ADDR_LEN);
1034                                 neg->timeout = 0;
1035                                 neg->pkt->pkt_header.ph.code = PADR_CODE;
1036                                 init_tags(sp);
1037                                 insert_tag(sp, utag);      /* Host Unique */
1038                                 if ((tag = get_tag(ph, PTT_AC_COOKIE)))
1039                                         insert_tag(sp, tag); /* return cookie */
1040                                 if ((tag = get_tag(ph, PTT_AC_NAME))) { 
1041                                         insert_tag(sp, tag); /* return it */
1042                                         send_acname(sp, tag);
1043                                 }
1044                                 insert_tag(sp, &neg->service.hdr); /* Service */
1045                                 scan_tags(sp, ph);
1046                                 make_packet(sp);
1047                                 sp->state = PPPOE_SREQ;
1048                                 sendpacket(sp);
1049                                 break;
1050                         case    PADR_CODE:
1051
1052                                 /*
1053                                  * We are a server:
1054                                  * Use the ac_cookie tag to find the 
1055                                  * hook this is in response to.
1056                                  */
1057                                 utag = get_tag(ph, PTT_AC_COOKIE);
1058                                 if ((utag == NULL)
1059                                 || (ntohs(utag->tag_len) != sizeof(sp))) {
1060                                         LEAVE(ENETUNREACH);
1061                                 }
1062
1063                                 sendhook = pppoe_finduniq(node, utag);
1064                                 if (sendhook == NULL) {
1065                                         LEAVE(ENETUNREACH);
1066                                 }
1067
1068                                 /*
1069                                  * Check the session is in the right state.
1070                                  * It needs to be in PPPOE_SOFFER
1071                                  * or PPPOE_NEWCONNECTED. If the latter,
1072                                  * then this is a retry by the client.
1073                                  * so be nice, and resend.
1074                                  */
1075                                 sp = sendhook->private;
1076                                 if (sp->state == PPPOE_NEWCONNECTED) {
1077                                         /*
1078                                          * Whoa! drop back to resend that 
1079                                          * PADS packet.
1080                                          * We should still have a copy of it.
1081                                          */
1082                                         sp->state = PPPOE_SOFFER;
1083                                 }
1084                                 if (sp->state != PPPOE_SOFFER) {
1085                                         LEAVE (ENETUNREACH);
1086                                         break;
1087                                 }
1088                                 neg = sp->neg;
1089                                 callout_stop(&neg->timeout_ch);
1090                                 neg->pkt->pkt_header.ph.code = PADS_CODE;
1091                                 if (sp->Session_ID == 0)
1092                                         neg->pkt->pkt_header.ph.sid =
1093                                             htons(sp->Session_ID
1094                                                 = get_new_sid(node));
1095                                 send_sessionid(sp);
1096                                 neg->timeout = 0;
1097                                 /*
1098                                  * start working out the tags to respond with.
1099                                  */
1100                                 init_tags(sp);
1101                                 insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1102                                 if ((tag = get_tag(ph, PTT_SRV_NAME)))
1103                                         insert_tag(sp, tag);/* return service */
1104                                 if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1105                                         insert_tag(sp, tag); /* return it */
1106                                 insert_tag(sp, utag);   /* ac_cookie */
1107                                 scan_tags(sp, ph);
1108                                 make_packet(sp);
1109                                 sp->state = PPPOE_NEWCONNECTED;
1110                                 sendpacket(sp);
1111                                 /*
1112                                  * Having sent the last Negotiation header,
1113                                  * Set up the stored packet header to 
1114                                  * be correct for the actual session.
1115                                  * But keep the negotialtion stuff
1116                                  * around in case we need to resend this last 
1117                                  * packet. We'll discard it when we move
1118                                  * from NEWCONNECTED to CONNECTED
1119                                  */
1120                                 sp->pkt_hdr = neg->pkt->pkt_header;
1121                                 if (pppoe_mode == PPPOE_NONSTANDARD)
1122                                         sp->pkt_hdr.eh.ether_type
1123                                                 = ETHERTYPE_PPPOE_STUPID_SESS;
1124                                 else
1125                                         sp->pkt_hdr.eh.ether_type
1126                                                 = ETHERTYPE_PPPOE_SESS;
1127                                 sp->pkt_hdr.ph.code = 0;
1128                                 pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1129                                 break;
1130                         case    PADS_CODE:
1131                                 /*
1132                                  * We are a client:
1133                                  * Use the host_uniq tag to find the 
1134                                  * hook this is in response to.
1135                                  * take the session ID and store it away.
1136                                  * Also make sure the pre-made header is
1137                                  * correct and set us into Session mode.
1138                                  */
1139                                 utag = get_tag(ph, PTT_HOST_UNIQ);
1140                                 if ((utag == NULL)
1141                                 || (ntohs(utag->tag_len) != sizeof(sp))) {
1142                                         LEAVE (ENETUNREACH);
1143                                         break;
1144                                 }
1145                                 sendhook = pppoe_finduniq(node, utag);
1146                                 if (sendhook == NULL) {
1147                                         LEAVE(ENETUNREACH);
1148                                 }
1149
1150                                 /*
1151                                  * Check the session is in the right state.
1152                                  * It needs to be in PPPOE_SREQ.
1153                                  */
1154                                 sp = sendhook->private;
1155                                 if (sp->state != PPPOE_SREQ) {
1156                                         LEAVE(ENETUNREACH);
1157                                 }
1158                                 neg = sp->neg;
1159                                 callout_stop(&neg->timeout_ch);
1160                                 neg->pkt->pkt_header.ph.sid = wh->ph.sid;
1161                                 sp->Session_ID = ntohs(wh->ph.sid);
1162                                 send_sessionid(sp);
1163                                 neg->timeout = 0;
1164                                 sp->state = PPPOE_CONNECTED;
1165                                 /*
1166                                  * Now we have gone to Connected mode, 
1167                                  * Free all resources needed for 
1168                                  * negotiation.
1169                                  * Keep a copy of the header we will be using.
1170                                  */
1171                                 sp->pkt_hdr = neg->pkt->pkt_header;
1172                                 if (pppoe_mode == PPPOE_NONSTANDARD)
1173                                         sp->pkt_hdr.eh.ether_type
1174                                                 = ETHERTYPE_PPPOE_STUPID_SESS;
1175                                 else
1176                                         sp->pkt_hdr.eh.ether_type
1177                                                 = ETHERTYPE_PPPOE_SESS;
1178                                 sp->pkt_hdr.ph.code = 0;
1179                                 m_freem(neg->m);
1180                                 kfree(sp->neg, M_NETGRAPH);
1181                                 sp->neg = NULL;
1182                                 pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1183                                 break;
1184                         case    PADT_CODE:
1185                                 /*
1186                                  * Send a 'close' message to the controlling
1187                                  * process (the one that set us up);
1188                                  * And then tear everything down.
1189                                  *
1190                                  * Find matching peer/session combination.
1191                                  */
1192                                 sendhook = pppoe_findsession(node, wh);
1193                                 NG_FREE_DATA(m, meta); /* no longer needed */
1194                                 if (sendhook == NULL) {
1195                                         LEAVE(ENETUNREACH);
1196                                 }
1197                                 /* send message to creator */
1198                                 /* close hook */
1199                                 if (sendhook) {
1200                                         ng_destroy_hook(sendhook);
1201                                 }
1202                                 break;
1203                         default:
1204                                 LEAVE(EPFNOSUPPORT);
1205                         }
1206                         break;
1207                 case    ETHERTYPE_PPPOE_STUPID_SESS:
1208                 case    ETHERTYPE_PPPOE_SESS:
1209                         /*
1210                          * find matching peer/session combination.
1211                          */
1212                         sendhook = pppoe_findsession(node, wh);
1213                         if (sendhook == NULL) {
1214                                 LEAVE (ENETUNREACH);
1215                                 break;
1216                         }
1217                         sp = sendhook->private;
1218                         m_adj(m, sizeof(*wh));
1219                         if (m->m_pkthdr.len < length) {
1220                                 /* Packet too short, dump it */
1221                                 LEAVE(EMSGSIZE);
1222                         }
1223
1224                         /* Also need to trim excess at the end */
1225                         if (m->m_pkthdr.len > length) {
1226                                 m_adj(m, -((int)(m->m_pkthdr.len - length)));
1227                         }
1228                         if ( sp->state != PPPOE_CONNECTED) {
1229                                 if (sp->state == PPPOE_NEWCONNECTED) {
1230                                         sp->state = PPPOE_CONNECTED;
1231                                         /*
1232                                          * Now we have gone to Connected mode, 
1233                                          * Free all resources needed for 
1234                                          * negotiation. Be paranoid about
1235                                          * whether there may be a timeout.
1236                                          */
1237                                         m_freem(sp->neg->m);
1238                                         callout_stop(&sp->neg->timeout_ch);
1239                                         kfree(sp->neg, M_NETGRAPH);
1240                                         sp->neg = NULL;
1241                                 } else {
1242                                         LEAVE (ENETUNREACH);
1243                                         break;
1244                                 }
1245                         }
1246                         NG_SEND_DATA( error, sendhook, m, meta);
1247                         break;
1248                 default:
1249                         LEAVE(EPFNOSUPPORT);
1250                 }
1251         } else {
1252                 /*
1253                  *      Not ethernet or debug hook..
1254                  *
1255                  * The packet has come in on a normal hook.
1256                  * We need to find out what kind of hook,
1257                  * So we can decide how to handle it.
1258                  * Check the hook's state.
1259                  */
1260                 sp = hook->private;
1261                 switch (sp->state) {
1262                 case    PPPOE_NEWCONNECTED:
1263                 case    PPPOE_CONNECTED: {
1264                         static const u_char addrctrl[] = { 0xff, 0x03 };
1265                         struct pppoe_full_hdr *wh;
1266
1267                         /*
1268                          * Remove PPP address and control fields, if any.
1269                          * For example, ng_ppp(4) always sends LCP packets
1270                          * with address and control fields as required by
1271                          * generic PPP. PPPoE is an exception to the rule.
1272                          */
1273                         if (m->m_pkthdr.len >= 2) {
1274                                 if (m->m_len < 2 && !(m = m_pullup(m, 2)))
1275                                         LEAVE(ENOBUFS);
1276                                 if (bcmp(mtod(m, u_char *), addrctrl, 2) == 0)
1277                                         m_adj(m, 2);
1278                         }
1279                         /*
1280                          * Bang in a pre-made header, and set the length up
1281                          * to be correct. Then send it to the ethernet driver.
1282                          * But first correct the length.
1283                          */
1284                         sp->pkt_hdr.ph.length = htons((short)(m->m_pkthdr.len));
1285                         M_PREPEND(m, sizeof(*wh), MB_DONTWAIT);
1286                         if (m == NULL) {
1287                                 LEAVE(ENOBUFS);
1288                         }
1289                         wh = mtod(m, struct pppoe_full_hdr *);
1290                         bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1291                         NG_SEND_DATA( error, privp->ethernet_hook, m, meta);
1292                         privp->packets_out++;
1293                         break;
1294                         }
1295                 case    PPPOE_PRIMED:
1296                         /*
1297                          * A PADI packet is being returned by the application
1298                          * that has set up this hook. This indicates that it 
1299                          * wants us to offer service.
1300                          */
1301                         neg = sp->neg;
1302                         if (m->m_len < sizeof(*wh)) {
1303                                 m = m_pullup(m, sizeof(*wh));
1304                                 if (m == NULL) {
1305                                         LEAVE(ENOBUFS);
1306                                 }
1307                         }
1308                         wh = mtod(m, struct pppoe_full_hdr *);
1309                         ph = &wh->ph;
1310                         length = ntohs(wh->ph.length);
1311                         code = wh->ph.code; 
1312                         if ( code != PADI_CODE) {
1313                                 LEAVE(EINVAL);
1314                         };
1315                         callout_stop(&neg->timeout_ch);
1316
1317                         /*
1318                          * This is the first time we hear
1319                          * from the client, so note it's
1320                          * unicast address, replacing the
1321                          * broadcast address.
1322                          */
1323                         bcopy(wh->eh.ether_shost,
1324                                 neg->pkt->pkt_header.eh.ether_dhost,
1325                                 ETHER_ADDR_LEN);
1326                         sp->state = PPPOE_SOFFER;
1327                         neg->timeout = 0;
1328                         neg->pkt->pkt_header.ph.code = PADO_CODE;
1329
1330                         /*
1331                          * start working out the tags to respond with.
1332                          */
1333                         uniqtag.hdr.tag_type = PTT_AC_COOKIE;
1334                         uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(sp));
1335                         uniqtag.data.pointer = sp;
1336                         init_tags(sp);
1337                         insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1338                         if ((tag = get_tag(ph, PTT_SRV_NAME)))
1339                                 insert_tag(sp, tag);      /* return service */
1340                         /*
1341                          * If we have a NULL service request
1342                          * and have an extra service defined in this hook,
1343                          * then also add a tag for the extra service.
1344                          * XXX this is a hack. eventually we should be able
1345                          * to support advertising many services, not just one 
1346                          */
1347                         if (((tag == NULL) || (tag->tag_len == 0))
1348                         && (neg->service.hdr.tag_len != 0)) {
1349                                 insert_tag(sp, &neg->service.hdr); /* SERVICE */
1350                         }
1351                         if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1352                                 insert_tag(sp, tag); /* returned hostunique */
1353                         insert_tag(sp, &uniqtag.hdr);
1354                         scan_tags(sp, ph);
1355                         make_packet(sp);
1356                         sendpacket(sp);
1357                         break;
1358
1359                 /*
1360                  * Packets coming from the hook make no sense
1361                  * to sessions in these states. Throw them away.
1362                  */
1363                 case    PPPOE_SINIT:
1364                 case    PPPOE_SREQ:
1365                 case    PPPOE_SOFFER:
1366                 case    PPPOE_SNONE:
1367                 case    PPPOE_LISTENING:
1368                 case    PPPOE_DEAD:
1369                 default:
1370                         LEAVE(ENETUNREACH);
1371                 }
1372         }
1373 quit:
1374         NG_FREE_DATA(m, meta);
1375         return error;
1376 }
1377
1378 /*
1379  * Do local shutdown processing..
1380  * If we are a persistant device, we might refuse to go away, and
1381  * we'd only remove our links and reset ourself.
1382  */
1383 static int
1384 ng_pppoe_rmnode(node_p node)
1385 {
1386         const priv_p privdata = node->private;
1387
1388 AAA
1389         node->flags |= NG_INVALID;
1390         ng_cutlinks(node);
1391         ng_unname(node);
1392         node->private = NULL;
1393         ng_unref(privdata->node);
1394         kfree(privdata, M_NETGRAPH);
1395         return (0);
1396 }
1397
1398 /*
1399  * This is called once we've already connected a new hook to the other node.
1400  * It gives us a chance to balk at the last minute.
1401  */
1402 static int
1403 ng_pppoe_connect(hook_p hook)
1404 {
1405         /* be really amiable and just say "YUP that's OK by me! " */
1406         return (0);
1407 }
1408
1409 /*
1410  * Hook disconnection
1411  *
1412  * Clean up all dangling links and information about the session/hook.
1413  * For this type, removal of the last link destroys the node
1414  */
1415 static int
1416 ng_pppoe_disconnect(hook_p hook)
1417 {
1418         node_p node = hook->node;
1419         priv_p privp = node->private;
1420         sessp   sp;
1421         int     hooks;
1422
1423 AAA
1424         hooks = node->numhooks; /* this one already not counted */
1425         if (hook->private == &privp->debug_hook) {
1426                 privp->debug_hook = NULL;
1427         } else if (hook->private == &privp->ethernet_hook) {
1428                 privp->ethernet_hook = NULL;
1429                 ng_rmnode(node);
1430         } else {
1431                 sp = hook->private;
1432                 if (sp->state != PPPOE_SNONE ) {
1433                         pppoe_send_event(sp, NGM_PPPOE_CLOSE);
1434                 }
1435                 /*
1436                  * According to the spec, if we are connected,
1437                  * we should send a DISC packet if we are shutting down
1438                  * a session.
1439                  */
1440                 if ((privp->ethernet_hook)
1441                 && ((sp->state == PPPOE_CONNECTED)
1442                  || (sp->state == PPPOE_NEWCONNECTED))) {
1443                         struct mbuf *m;
1444                         struct pppoe_full_hdr *wh;
1445                         struct pppoe_tag *tag;
1446                         int     msglen = strlen(SIGNOFF);
1447                         void *dummy = NULL;
1448                         int error = 0;
1449
1450                         /* revert the stored header to DISC/PADT mode */
1451                         wh = &sp->pkt_hdr;
1452                         wh->ph.code = PADT_CODE;
1453                         if (pppoe_mode == PPPOE_NONSTANDARD)
1454                                 wh->eh.ether_type = ETHERTYPE_PPPOE_STUPID_DISC;
1455                         else
1456                                 wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1457
1458                         /* generate a packet of that type */
1459                         MGETHDR(m, MB_DONTWAIT, MT_DATA);
1460                         if(m == NULL)
1461                                 kprintf("pppoe: Session out of mbufs\n");
1462                         else {
1463                                 m->m_pkthdr.rcvif = NULL;
1464                                 m->m_pkthdr.len = m->m_len = sizeof(*wh);
1465                                 bcopy((caddr_t)wh, mtod(m, caddr_t),
1466                                     sizeof(*wh));
1467                                 /*
1468                                  * Add a General error message and adjust
1469                                  * sizes
1470                                  */
1471                                 wh = mtod(m, struct pppoe_full_hdr *);
1472                                 tag = wh->ph.tag;
1473                                 tag->tag_type = PTT_GEN_ERR;
1474                                 tag->tag_len = htons((u_int16_t)msglen);
1475                                 strncpy(tag->tag_data, SIGNOFF, msglen);
1476                                 m->m_pkthdr.len = (m->m_len += sizeof(*tag) +
1477                                     msglen);
1478                                 wh->ph.length = htons(sizeof(*tag) + msglen);
1479                                 NG_SEND_DATA(error, privp->ethernet_hook, m,
1480                                     dummy);
1481                         }
1482                 }
1483                 /*
1484                  * As long as we have somewhere to store the timeout handle,
1485                  * we may have a timeout pending.. get rid of it.
1486                  */
1487                 if (sp->neg) {
1488                         callout_stop(&sp->neg->timeout_ch);
1489                         if (sp->neg->m)
1490                                 m_freem(sp->neg->m);
1491                         kfree(sp->neg, M_NETGRAPH);
1492                 }
1493                 kfree(sp, M_NETGRAPH);
1494                 hook->private = NULL;
1495                 /* work out how many session hooks there are */
1496                 /* Node goes away on last session hook removal */
1497                 if (privp->ethernet_hook) hooks -= 1;
1498                 if (privp->debug_hook) hooks -= 1;
1499         }
1500         if (node->numhooks == 0)
1501                 ng_rmnode(node);
1502         return (0);
1503 }
1504
1505 /*
1506  * timeouts come here.
1507  */
1508 static void
1509 pppoe_ticker(void *arg)
1510 {
1511         hook_p hook = arg;
1512         sessp   sp = hook->private;
1513         negp    neg = sp->neg;
1514         int     error = 0;
1515         struct mbuf *m0 = NULL;
1516         priv_p privp = hook->node->private;
1517         meta_p dummy = NULL;
1518
1519         crit_enter();
1520 AAA
1521         switch(sp->state) {
1522                 /*
1523                  * resend the last packet, using an exponential backoff.
1524                  * After a period of time, stop growing the backoff,
1525                  * and either leave it, or revert to the start.
1526                  */
1527         case    PPPOE_SINIT:
1528         case    PPPOE_SREQ:
1529                 /* timeouts on these produce resends */
1530                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1531                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1532                 callout_reset(&neg->timeout_ch, neg->timeout * hz,
1533                                 pppoe_ticker, hook);
1534                 if ((neg->timeout <<= 1) > PPPOE_TIMEOUT_LIMIT) {
1535                         if (sp->state == PPPOE_SREQ) {
1536                                 /* revert to SINIT mode */
1537                                 pppoe_start(sp);
1538                         } else {
1539                                 neg->timeout = PPPOE_TIMEOUT_LIMIT;
1540                         }
1541                 }
1542                 break;
1543         case    PPPOE_PRIMED:
1544         case    PPPOE_SOFFER:
1545                 /* a timeout on these says "give up" */
1546                 ng_destroy_hook(hook);
1547                 break;
1548         default:
1549                 /* timeouts have no meaning in other states */
1550                 kprintf("pppoe: unexpected timeout\n");
1551         }
1552         crit_exit();
1553 }
1554
1555
1556 static void
1557 sendpacket(sessp sp)
1558 {
1559         int     error = 0;
1560         struct mbuf *m0 = NULL;
1561         hook_p hook = sp->hook;
1562         negp    neg = sp->neg;
1563         priv_p  privp = hook->node->private;
1564         meta_p dummy = NULL;
1565
1566 AAA
1567         switch(sp->state) {
1568         case    PPPOE_LISTENING:
1569         case    PPPOE_DEAD:
1570         case    PPPOE_SNONE:
1571         case    PPPOE_CONNECTED:
1572                 kprintf("pppoe: sendpacket: unexpected state\n");
1573                 break;
1574
1575         case    PPPOE_NEWCONNECTED:
1576                 /* send the PADS without a timeout - we're now connected */
1577                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1578                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1579                 break;
1580
1581         case    PPPOE_PRIMED:
1582                 /* No packet to send, but set up the timeout */
1583                 callout_reset(&neg->timeout_ch, PPPOE_OFFER_TIMEOUT * hz,
1584                                 pppoe_ticker, hook);
1585                 break;
1586
1587         case    PPPOE_SOFFER:
1588                 /*
1589                  * send the offer but if they don't respond
1590                  * in PPPOE_OFFER_TIMEOUT seconds, forget about it.
1591                  */
1592                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1593                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1594                 callout_reset(&neg->timeout_ch, PPPOE_OFFER_TIMEOUT * hz,
1595                                 pppoe_ticker, hook);
1596                 break;
1597
1598         case    PPPOE_SINIT:
1599         case    PPPOE_SREQ:
1600                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1601                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1602                 callout_reset(&neg->timeout_ch, PPPOE_INITIAL_TIMEOUT * hz,
1603                                 pppoe_ticker, hook);
1604                 neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1605                 break;
1606
1607         default:
1608                 error = EINVAL;
1609                 kprintf("pppoe: timeout: bad state\n");
1610         }
1611         /* return (error); */
1612 }
1613
1614 /*
1615  * Parse an incoming packet to see if any tags should be copied to the
1616  * output packet. Don't do any tags that have been handled in the main
1617  * state machine.
1618  */
1619 static const struct pppoe_tag* 
1620 scan_tags(sessp sp, const struct pppoe_hdr* ph)
1621 {
1622         const char *const end = (const char *)next_tag(ph);
1623         const char *ptn;
1624         const struct pppoe_tag *pt = &ph->tag[0];
1625         /*
1626          * Keep processing tags while a tag header will still fit.
1627          */
1628 AAA
1629         while((const char*)(pt + 1) <= end) {
1630                 /*
1631                  * If the tag data would go past the end of the packet, abort.
1632                  */
1633                 ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
1634                 if(ptn > end)
1635                         return NULL;
1636
1637                 switch (pt->tag_type) {
1638                 case    PTT_RELAY_SID:
1639                         insert_tag(sp, pt);
1640                         break;
1641                 case    PTT_EOL:
1642                         return NULL;
1643                 case    PTT_SRV_NAME:
1644                 case    PTT_AC_NAME:
1645                 case    PTT_HOST_UNIQ:
1646                 case    PTT_AC_COOKIE:
1647                 case    PTT_VENDOR:
1648                 case    PTT_SRV_ERR:
1649                 case    PTT_SYS_ERR:
1650                 case    PTT_GEN_ERR:
1651                         break;
1652                 }
1653                 pt = (const struct pppoe_tag*)ptn;
1654         }
1655         return NULL;
1656 }
1657         
1658 static  int
1659 pppoe_send_event(sessp sp, enum cmd cmdid)
1660 {
1661         int error;
1662         struct ng_mesg *msg;
1663         struct ngpppoe_sts *sts;
1664
1665 AAA
1666         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, cmdid,
1667                         sizeof(struct ngpppoe_sts), M_NOWAIT);
1668         if (msg == NULL)
1669                 return (ENOMEM);
1670         sts = (struct ngpppoe_sts *)msg->data;
1671         strlcpy(sts->hook, sp->hook->name, NG_HOOKSIZ);
1672         error = ng_send_msg(sp->hook->node, msg, sp->creator, NULL);
1673         return (error);
1674 }