GNU Linux-libre 4.14.266-gnu1
[releases.git] / drivers / isdn / hisax / isdnl3.c
1 /* $Id: isdnl3.c,v 2.22.2.3 2004/01/13 14:31:25 keil Exp $
2  *
3  * Author       Karsten Keil
4  *              based on the teles driver from Jan den Ouden
5  * Copyright    by Karsten Keil      <keil@isdn4linux.de>
6  *
7  * This software may be used and distributed according to the terms
8  * of the GNU General Public License, incorporated herein by reference.
9  *
10  * For changes and modifications please read
11  * Documentation/isdn/HiSax.cert
12  *
13  * Thanks to    Jan den Ouden
14  *              Fritz Elfert
15  *
16  */
17
18 #include <linux/init.h>
19 #include <linux/slab.h>
20 #include "hisax.h"
21 #include "isdnl3.h"
22
23 const char *l3_revision = "$Revision: 2.22.2.3 $";
24
25 static struct Fsm l3fsm;
26
27 enum {
28         ST_L3_LC_REL,
29         ST_L3_LC_ESTAB_WAIT,
30         ST_L3_LC_REL_DELAY,
31         ST_L3_LC_REL_WAIT,
32         ST_L3_LC_ESTAB,
33 };
34
35 #define L3_STATE_COUNT (ST_L3_LC_ESTAB + 1)
36
37 static char *strL3State[] =
38 {
39         "ST_L3_LC_REL",
40         "ST_L3_LC_ESTAB_WAIT",
41         "ST_L3_LC_REL_DELAY",
42         "ST_L3_LC_REL_WAIT",
43         "ST_L3_LC_ESTAB",
44 };
45
46 enum {
47         EV_ESTABLISH_REQ,
48         EV_ESTABLISH_IND,
49         EV_ESTABLISH_CNF,
50         EV_RELEASE_REQ,
51         EV_RELEASE_CNF,
52         EV_RELEASE_IND,
53         EV_TIMEOUT,
54 };
55
56 #define L3_EVENT_COUNT (EV_TIMEOUT + 1)
57
58 static char *strL3Event[] =
59 {
60         "EV_ESTABLISH_REQ",
61         "EV_ESTABLISH_IND",
62         "EV_ESTABLISH_CNF",
63         "EV_RELEASE_REQ",
64         "EV_RELEASE_CNF",
65         "EV_RELEASE_IND",
66         "EV_TIMEOUT",
67 };
68
69 static __printf(2, 3) void
70         l3m_debug(struct FsmInst *fi, char *fmt, ...)
71 {
72         va_list args;
73         struct PStack *st = fi->userdata;
74
75         va_start(args, fmt);
76         VHiSax_putstatus(st->l1.hardware, st->l3.debug_id, fmt, args);
77         va_end(args);
78 }
79
80 u_char *
81 findie(u_char *p, int size, u_char ie, int wanted_set)
82 {
83         int l, codeset, maincodeset;
84         u_char *pend = p + size;
85
86         /* skip protocol discriminator, callref and message type */
87         p++;
88         l = (*p++) & 0xf;
89         p += l;
90         p++;
91         codeset = 0;
92         maincodeset = 0;
93         /* while there are bytes left... */
94         while (p < pend) {
95                 if ((*p & 0xf0) == 0x90) {
96                         codeset = *p & 0x07;
97                         if (!(*p & 0x08))
98                                 maincodeset = codeset;
99                 }
100                 if (*p & 0x80)
101                         p++;
102                 else {
103                         if (codeset == wanted_set) {
104                                 if (*p == ie)
105                                 { /* improved length check (Werner Cornelius) */
106                                         if ((pend - p) < 2)
107                                                 return (NULL);
108                                         if (*(p + 1) > (pend - (p + 2)))
109                                                 return (NULL);
110                                         return (p);
111                                 }
112
113                                 if (*p > ie)
114                                         return (NULL);
115                         }
116                         p++;
117                         l = *p++;
118                         p += l;
119                         codeset = maincodeset;
120                 }
121         }
122         return (NULL);
123 }
124
125 int
126 getcallref(u_char *p)
127 {
128         int l, cr = 0;
129
130         p++;                    /* prot discr */
131         if (*p & 0xfe)          /* wrong callref BRI only 1 octet*/
132                 return (-2);
133         l = 0xf & *p++;         /* callref length */
134         if (!l)                 /* dummy CallRef */
135                 return (-1);
136         cr = *p++;
137         return (cr);
138 }
139
140 static int OrigCallRef = 0;
141
142 int
143 newcallref(void)
144 {
145         if (OrigCallRef == 127)
146                 OrigCallRef = 1;
147         else
148                 OrigCallRef++;
149         return (OrigCallRef);
150 }
151
152 void
153 newl3state(struct l3_process *pc, int state)
154 {
155         if (pc->debug & L3_DEB_STATE)
156                 l3_debug(pc->st, "%s cr %d %d --> %d", __func__,
157                          pc->callref & 0x7F,
158                          pc->state, state);
159         pc->state = state;
160 }
161
162 static void
163 L3ExpireTimer(struct L3Timer *t)
164 {
165         t->pc->st->lli.l4l3(t->pc->st, t->event, t->pc);
166 }
167
168 void
169 L3InitTimer(struct l3_process *pc, struct L3Timer *t)
170 {
171         t->pc = pc;
172         setup_timer(&t->tl, (void *)L3ExpireTimer, (long)t);
173 }
174
175 void
176 L3DelTimer(struct L3Timer *t)
177 {
178         del_timer(&t->tl);
179 }
180
181 int
182 L3AddTimer(struct L3Timer *t,
183            int millisec, int event)
184 {
185         if (timer_pending(&t->tl)) {
186                 printk(KERN_WARNING "L3AddTimer: timer already active!\n");
187                 return -1;
188         }
189         init_timer(&t->tl);
190         t->event = event;
191         t->tl.expires = jiffies + (millisec * HZ) / 1000;
192         add_timer(&t->tl);
193         return 0;
194 }
195
196 void
197 StopAllL3Timer(struct l3_process *pc)
198 {
199         L3DelTimer(&pc->timer);
200 }
201
202 struct sk_buff *
203 l3_alloc_skb(int len)
204 {
205         struct sk_buff *skb;
206
207         if (!(skb = alloc_skb(len + MAX_HEADER_LEN, GFP_ATOMIC))) {
208                 printk(KERN_WARNING "HiSax: No skb for D-channel\n");
209                 return (NULL);
210         }
211         skb_reserve(skb, MAX_HEADER_LEN);
212         return (skb);
213 }
214
215 static void
216 no_l3_proto(struct PStack *st, int pr, void *arg)
217 {
218         struct sk_buff *skb = arg;
219
220         HiSax_putstatus(st->l1.hardware, "L3", "no D protocol");
221         if (skb) {
222                 dev_kfree_skb(skb);
223         }
224 }
225
226 static int
227 no_l3_proto_spec(struct PStack *st, isdn_ctrl *ic)
228 {
229         printk(KERN_WARNING "HiSax: no specific protocol handler for proto %lu\n", ic->arg & 0xFF);
230         return (-1);
231 }
232
233 struct l3_process
234 *getl3proc(struct PStack *st, int cr)
235 {
236         struct l3_process *p = st->l3.proc;
237
238         while (p)
239                 if (p->callref == cr)
240                         return (p);
241                 else
242                         p = p->next;
243         return (NULL);
244 }
245
246 struct l3_process
247 *new_l3_process(struct PStack *st, int cr)
248 {
249         struct l3_process *p, *np;
250
251         if (!(p = kmalloc(sizeof(struct l3_process), GFP_ATOMIC))) {
252                 printk(KERN_ERR "HiSax can't get memory for cr %d\n", cr);
253                 return (NULL);
254         }
255         if (!st->l3.proc)
256                 st->l3.proc = p;
257         else {
258                 np = st->l3.proc;
259                 while (np->next)
260                         np = np->next;
261                 np->next = p;
262         }
263         p->next = NULL;
264         p->debug = st->l3.debug;
265         p->callref = cr;
266         p->state = 0;
267         p->chan = NULL;
268         p->st = st;
269         p->N303 = st->l3.N303;
270         L3InitTimer(p, &p->timer);
271         return (p);
272 };
273
274 void
275 release_l3_process(struct l3_process *p)
276 {
277         struct l3_process *np, *pp = NULL;
278
279         if (!p)
280                 return;
281         np = p->st->l3.proc;
282         while (np) {
283                 if (np == p) {
284                         StopAllL3Timer(p);
285                         if (pp)
286                                 pp->next = np->next;
287                         else if (!(p->st->l3.proc = np->next) &&
288                                  !test_bit(FLG_PTP, &p->st->l2.flag)) {
289                                 if (p->debug)
290                                         l3_debug(p->st, "release_l3_process: last process");
291                                 if (skb_queue_empty(&p->st->l3.squeue)) {
292                                         if (p->debug)
293                                                 l3_debug(p->st, "release_l3_process: release link");
294                                         if (p->st->protocol != ISDN_PTYPE_NI1)
295                                                 FsmEvent(&p->st->l3.l3m, EV_RELEASE_REQ, NULL);
296                                         else
297                                                 FsmEvent(&p->st->l3.l3m, EV_RELEASE_IND, NULL);
298                                 } else {
299                                         if (p->debug)
300                                                 l3_debug(p->st, "release_l3_process: not release link");
301                                 }
302                         }
303                         kfree(p);
304                         return;
305                 }
306                 pp = np;
307                 np = np->next;
308         }
309         printk(KERN_ERR "HiSax internal L3 error CR(%d) not in list\n", p->callref);
310         l3_debug(p->st, "HiSax internal L3 error CR(%d) not in list", p->callref);
311 };
312
313 static void
314 l3ml3p(struct PStack *st, int pr)
315 {
316         struct l3_process *p = st->l3.proc;
317         struct l3_process *np;
318
319         while (p) {
320                 /* p might be kfreed under us, so we need to save where we want to go on */
321                 np = p->next;
322                 st->l3.l3ml3(st, pr, p);
323                 p = np;
324         }
325 }
326
327 void
328 setstack_l3dc(struct PStack *st, struct Channel *chanp)
329 {
330         char tmp[64];
331
332         st->l3.proc   = NULL;
333         st->l3.global = NULL;
334         skb_queue_head_init(&st->l3.squeue);
335         st->l3.l3m.fsm = &l3fsm;
336         st->l3.l3m.state = ST_L3_LC_REL;
337         st->l3.l3m.debug = 1;
338         st->l3.l3m.userdata = st;
339         st->l3.l3m.userint = 0;
340         st->l3.l3m.printdebug = l3m_debug;
341         FsmInitTimer(&st->l3.l3m, &st->l3.l3m_timer);
342         strcpy(st->l3.debug_id, "L3DC ");
343         st->lli.l4l3_proto = no_l3_proto_spec;
344
345 #ifdef CONFIG_HISAX_EURO
346         if (st->protocol == ISDN_PTYPE_EURO) {
347                 setstack_dss1(st);
348         } else
349 #endif
350 #ifdef CONFIG_HISAX_NI1
351                 if (st->protocol == ISDN_PTYPE_NI1) {
352                         setstack_ni1(st);
353                 } else
354 #endif
355 #ifdef CONFIG_HISAX_1TR6
356                         if (st->protocol == ISDN_PTYPE_1TR6) {
357                                 setstack_1tr6(st);
358                         } else
359 #endif
360                                 if (st->protocol == ISDN_PTYPE_LEASED) {
361                                         st->lli.l4l3 = no_l3_proto;
362                                         st->l2.l2l3 = no_l3_proto;
363                                         st->l3.l3ml3 = no_l3_proto;
364                                         printk(KERN_INFO "HiSax: Leased line mode\n");
365                                 } else {
366                                         st->lli.l4l3 = no_l3_proto;
367                                         st->l2.l2l3 = no_l3_proto;
368                                         st->l3.l3ml3 = no_l3_proto;
369                                         sprintf(tmp, "protocol %s not supported",
370                                                 (st->protocol == ISDN_PTYPE_1TR6) ? "1tr6" :
371                                                 (st->protocol == ISDN_PTYPE_EURO) ? "euro" :
372                                                 (st->protocol == ISDN_PTYPE_NI1) ? "ni1" :
373                                                 "unknown");
374                                         printk(KERN_WARNING "HiSax: %s\n", tmp);
375                                         st->protocol = -1;
376                                 }
377 }
378
379 static void
380 isdnl3_trans(struct PStack *st, int pr, void *arg) {
381         st->l3.l3l2(st, pr, arg);
382 }
383
384 void
385 releasestack_isdnl3(struct PStack *st)
386 {
387         while (st->l3.proc)
388                 release_l3_process(st->l3.proc);
389         if (st->l3.global) {
390                 StopAllL3Timer(st->l3.global);
391                 kfree(st->l3.global);
392                 st->l3.global = NULL;
393         }
394         FsmDelTimer(&st->l3.l3m_timer, 54);
395         skb_queue_purge(&st->l3.squeue);
396 }
397
398 void
399 setstack_l3bc(struct PStack *st, struct Channel *chanp)
400 {
401
402         st->l3.proc   = NULL;
403         st->l3.global = NULL;
404         skb_queue_head_init(&st->l3.squeue);
405         st->l3.l3m.fsm = &l3fsm;
406         st->l3.l3m.state = ST_L3_LC_REL;
407         st->l3.l3m.debug = 1;
408         st->l3.l3m.userdata = st;
409         st->l3.l3m.userint = 0;
410         st->l3.l3m.printdebug = l3m_debug;
411         strcpy(st->l3.debug_id, "L3BC ");
412         st->lli.l4l3 = isdnl3_trans;
413 }
414
415 #define DREL_TIMER_VALUE 40000
416
417 static void
418 lc_activate(struct FsmInst *fi, int event, void *arg)
419 {
420         struct PStack *st = fi->userdata;
421
422         FsmChangeState(fi, ST_L3_LC_ESTAB_WAIT);
423         st->l3.l3l2(st, DL_ESTABLISH | REQUEST, NULL);
424 }
425
426 static void
427 lc_connect(struct FsmInst *fi, int event, void *arg)
428 {
429         struct PStack *st = fi->userdata;
430         struct sk_buff *skb = arg;
431         int dequeued = 0;
432
433         FsmChangeState(fi, ST_L3_LC_ESTAB);
434         while ((skb = skb_dequeue(&st->l3.squeue))) {
435                 st->l3.l3l2(st, DL_DATA | REQUEST, skb);
436                 dequeued++;
437         }
438         if ((!st->l3.proc) &&  dequeued) {
439                 if (st->l3.debug)
440                         l3_debug(st, "lc_connect: release link");
441                 FsmEvent(&st->l3.l3m, EV_RELEASE_REQ, NULL);
442         } else
443                 l3ml3p(st, DL_ESTABLISH | INDICATION);
444 }
445
446 static void
447 lc_connected(struct FsmInst *fi, int event, void *arg)
448 {
449         struct PStack *st = fi->userdata;
450         struct sk_buff *skb = arg;
451         int dequeued = 0;
452
453         FsmDelTimer(&st->l3.l3m_timer, 51);
454         FsmChangeState(fi, ST_L3_LC_ESTAB);
455         while ((skb = skb_dequeue(&st->l3.squeue))) {
456                 st->l3.l3l2(st, DL_DATA | REQUEST, skb);
457                 dequeued++;
458         }
459         if ((!st->l3.proc) &&  dequeued) {
460                 if (st->l3.debug)
461                         l3_debug(st, "lc_connected: release link");
462                 FsmEvent(&st->l3.l3m, EV_RELEASE_REQ, NULL);
463         } else
464                 l3ml3p(st, DL_ESTABLISH | CONFIRM);
465 }
466
467 static void
468 lc_start_delay(struct FsmInst *fi, int event, void *arg)
469 {
470         struct PStack *st = fi->userdata;
471
472         FsmChangeState(fi, ST_L3_LC_REL_DELAY);
473         FsmAddTimer(&st->l3.l3m_timer, DREL_TIMER_VALUE, EV_TIMEOUT, NULL, 50);
474 }
475
476 static void
477 lc_start_delay_check(struct FsmInst *fi, int event, void *arg)
478 /* 20/09/00 - GE timer not user for NI-1 as layer 2 should stay up */
479 {
480         struct PStack *st = fi->userdata;
481
482         FsmChangeState(fi, ST_L3_LC_REL_DELAY);
483         /* 19/09/00 - GE timer not user for NI-1 */
484         if (st->protocol != ISDN_PTYPE_NI1)
485                 FsmAddTimer(&st->l3.l3m_timer, DREL_TIMER_VALUE, EV_TIMEOUT, NULL, 50);
486 }
487
488 static void
489 lc_release_req(struct FsmInst *fi, int event, void *arg)
490 {
491         struct PStack *st = fi->userdata;
492
493         if (test_bit(FLG_L2BLOCK, &st->l2.flag)) {
494                 if (st->l3.debug)
495                         l3_debug(st, "lc_release_req: l2 blocked");
496                 /* restart release timer */
497                 FsmAddTimer(&st->l3.l3m_timer, DREL_TIMER_VALUE, EV_TIMEOUT, NULL, 51);
498         } else {
499                 FsmChangeState(fi, ST_L3_LC_REL_WAIT);
500                 st->l3.l3l2(st, DL_RELEASE | REQUEST, NULL);
501         }
502 }
503
504 static void
505 lc_release_ind(struct FsmInst *fi, int event, void *arg)
506 {
507         struct PStack *st = fi->userdata;
508
509         FsmDelTimer(&st->l3.l3m_timer, 52);
510         FsmChangeState(fi, ST_L3_LC_REL);
511         skb_queue_purge(&st->l3.squeue);
512         l3ml3p(st, DL_RELEASE | INDICATION);
513 }
514
515 static void
516 lc_release_cnf(struct FsmInst *fi, int event, void *arg)
517 {
518         struct PStack *st = fi->userdata;
519
520         FsmChangeState(fi, ST_L3_LC_REL);
521         skb_queue_purge(&st->l3.squeue);
522         l3ml3p(st, DL_RELEASE | CONFIRM);
523 }
524
525
526 /* *INDENT-OFF* */
527 static struct FsmNode L3FnList[] __initdata =
528 {
529         {ST_L3_LC_REL,          EV_ESTABLISH_REQ,       lc_activate},
530         {ST_L3_LC_REL,          EV_ESTABLISH_IND,       lc_connect},
531         {ST_L3_LC_REL,          EV_ESTABLISH_CNF,       lc_connect},
532         {ST_L3_LC_ESTAB_WAIT,   EV_ESTABLISH_CNF,       lc_connected},
533         {ST_L3_LC_ESTAB_WAIT,   EV_RELEASE_REQ,         lc_start_delay},
534         {ST_L3_LC_ESTAB_WAIT,   EV_RELEASE_IND,         lc_release_ind},
535         {ST_L3_LC_ESTAB,        EV_RELEASE_IND,         lc_release_ind},
536         {ST_L3_LC_ESTAB,        EV_RELEASE_REQ,         lc_start_delay_check},
537         {ST_L3_LC_REL_DELAY,    EV_RELEASE_IND,         lc_release_ind},
538         {ST_L3_LC_REL_DELAY,    EV_ESTABLISH_REQ,       lc_connected},
539         {ST_L3_LC_REL_DELAY,    EV_TIMEOUT,             lc_release_req},
540         {ST_L3_LC_REL_WAIT,     EV_RELEASE_CNF,         lc_release_cnf},
541         {ST_L3_LC_REL_WAIT,     EV_ESTABLISH_REQ,       lc_activate},
542 };
543 /* *INDENT-ON* */
544
545 void
546 l3_msg(struct PStack *st, int pr, void *arg)
547 {
548         switch (pr) {
549         case (DL_DATA | REQUEST):
550                 if (st->l3.l3m.state == ST_L3_LC_ESTAB) {
551                         st->l3.l3l2(st, pr, arg);
552                 } else {
553                         struct sk_buff *skb = arg;
554
555                         skb_queue_tail(&st->l3.squeue, skb);
556                         FsmEvent(&st->l3.l3m, EV_ESTABLISH_REQ, NULL);
557                 }
558                 break;
559         case (DL_ESTABLISH | REQUEST):
560                 FsmEvent(&st->l3.l3m, EV_ESTABLISH_REQ, NULL);
561                 break;
562         case (DL_ESTABLISH | CONFIRM):
563                 FsmEvent(&st->l3.l3m, EV_ESTABLISH_CNF, NULL);
564                 break;
565         case (DL_ESTABLISH | INDICATION):
566                 FsmEvent(&st->l3.l3m, EV_ESTABLISH_IND, NULL);
567                 break;
568         case (DL_RELEASE | INDICATION):
569                 FsmEvent(&st->l3.l3m, EV_RELEASE_IND, NULL);
570                 break;
571         case (DL_RELEASE | CONFIRM):
572                 FsmEvent(&st->l3.l3m, EV_RELEASE_CNF, NULL);
573                 break;
574         case (DL_RELEASE | REQUEST):
575                 FsmEvent(&st->l3.l3m, EV_RELEASE_REQ, NULL);
576                 break;
577         }
578 }
579
580 int __init
581 Isdnl3New(void)
582 {
583         l3fsm.state_count = L3_STATE_COUNT;
584         l3fsm.event_count = L3_EVENT_COUNT;
585         l3fsm.strEvent = strL3Event;
586         l3fsm.strState = strL3State;
587         return FsmNew(&l3fsm, L3FnList, ARRAY_SIZE(L3FnList));
588 }
589
590 void
591 Isdnl3Free(void)
592 {
593         FsmFree(&l3fsm);
594 }