isdnl3.c revision 5a0e3ad6af8660be21ca98a971cd00f331318c05 
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
23const char *l3_revision = "$Revision: 2.22.2.3 $";
24
25static struct Fsm l3fsm;
26
27enum {
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
37static 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
46enum {
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
58static 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
69static void
70l3m_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
80u_char *
81findie(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
125int
126getcallref(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
140static int OrigCallRef = 0;
141
142int
143newcallref(void)
144{
145	if (OrigCallRef == 127)
146		OrigCallRef = 1;
147	else
148		OrigCallRef++;
149	return (OrigCallRef);
150}
151
152void
153newl3state(struct l3_process *pc, int state)
154{
155	if (pc->debug & L3_DEB_STATE)
156		l3_debug(pc->st, "newstate cr %d %d --> %d",
157			 pc->callref & 0x7F,
158			 pc->state, state);
159	pc->state = state;
160}
161
162static void
163L3ExpireTimer(struct L3Timer *t)
164{
165	t->pc->st->lli.l4l3(t->pc->st, t->event, t->pc);
166}
167
168void
169L3InitTimer(struct l3_process *pc, struct L3Timer *t)
170{
171	t->pc = pc;
172	t->tl.function = (void *) L3ExpireTimer;
173	t->tl.data = (long) t;
174	init_timer(&t->tl);
175}
176
177void
178L3DelTimer(struct L3Timer *t)
179{
180	del_timer(&t->tl);
181}
182
183int
184L3AddTimer(struct L3Timer *t,
185	   int millisec, int event)
186{
187	if (timer_pending(&t->tl)) {
188		printk(KERN_WARNING "L3AddTimer: timer already active!\n");
189		return -1;
190	}
191	init_timer(&t->tl);
192	t->event = event;
193	t->tl.expires = jiffies + (millisec * HZ) / 1000;
194	add_timer(&t->tl);
195	return 0;
196}
197
198void
199StopAllL3Timer(struct l3_process *pc)
200{
201	L3DelTimer(&pc->timer);
202}
203
204struct sk_buff *
205l3_alloc_skb(int len)
206{
207	struct sk_buff *skb;
208
209	if (!(skb = alloc_skb(len + MAX_HEADER_LEN, GFP_ATOMIC))) {
210		printk(KERN_WARNING "HiSax: No skb for D-channel\n");
211		return (NULL);
212	}
213	skb_reserve(skb, MAX_HEADER_LEN);
214	return (skb);
215}
216
217static void
218no_l3_proto(struct PStack *st, int pr, void *arg)
219{
220	struct sk_buff *skb = arg;
221
222	HiSax_putstatus(st->l1.hardware, "L3", "no D protocol");
223	if (skb) {
224		dev_kfree_skb(skb);
225	}
226}
227
228static int
229no_l3_proto_spec(struct PStack *st, isdn_ctrl *ic)
230{
231	printk(KERN_WARNING "HiSax: no specific protocol handler for proto %lu\n",ic->arg & 0xFF);
232	return(-1);
233}
234
235struct l3_process
236*getl3proc(struct PStack *st, int cr)
237{
238	struct l3_process *p = st->l3.proc;
239
240	while (p)
241		if (p->callref == cr)
242			return (p);
243		else
244			p = p->next;
245	return (NULL);
246}
247
248struct l3_process
249*new_l3_process(struct PStack *st, int cr)
250{
251	struct l3_process *p, *np;
252
253	if (!(p = kmalloc(sizeof(struct l3_process), GFP_ATOMIC))) {
254		printk(KERN_ERR "HiSax can't get memory for cr %d\n", cr);
255		return (NULL);
256	}
257	if (!st->l3.proc)
258		st->l3.proc = p;
259	else {
260		np = st->l3.proc;
261		while (np->next)
262			np = np->next;
263		np->next = p;
264	}
265	p->next = NULL;
266	p->debug = st->l3.debug;
267	p->callref = cr;
268	p->state = 0;
269	p->chan = NULL;
270	p->st = st;
271	p->N303 = st->l3.N303;
272	L3InitTimer(p, &p->timer);
273	return (p);
274};
275
276void
277release_l3_process(struct l3_process *p)
278{
279	struct l3_process *np, *pp = NULL;
280
281	if (!p)
282		return;
283	np = p->st->l3.proc;
284	while (np) {
285		if (np == p) {
286			StopAllL3Timer(p);
287			if (pp)
288				pp->next = np->next;
289			else if (!(p->st->l3.proc = np->next) &&
290				!test_bit(FLG_PTP, &p->st->l2.flag)) {
291				if (p->debug)
292					l3_debug(p->st, "release_l3_process: last process");
293				if (skb_queue_empty(&p->st->l3.squeue)) {
294					if (p->debug)
295						l3_debug(p->st, "release_l3_process: release link");
296					if (p->st->protocol != ISDN_PTYPE_NI1)
297						FsmEvent(&p->st->l3.l3m, EV_RELEASE_REQ, NULL);
298					else
299						FsmEvent(&p->st->l3.l3m, EV_RELEASE_IND, NULL);
300				} else {
301					if (p->debug)
302						l3_debug(p->st, "release_l3_process: not release link");
303				}
304			}
305			kfree(p);
306			return;
307		}
308		pp = np;
309		np = np->next;
310	}
311	printk(KERN_ERR "HiSax internal L3 error CR(%d) not in list\n", p->callref);
312	l3_debug(p->st, "HiSax internal L3 error CR(%d) not in list", p->callref);
313};
314
315static void
316l3ml3p(struct PStack *st, int pr)
317{
318	struct l3_process *p = st->l3.proc;
319	struct l3_process *np;
320
321	while (p) {
322		/* p might be kfreed under us, so we need to save where we want to go on */
323		np = p->next;
324		st->l3.l3ml3(st, pr, p);
325		p = np;
326	}
327}
328
329void
330setstack_l3dc(struct PStack *st, struct Channel *chanp)
331{
332	char tmp[64];
333
334	st->l3.proc   = NULL;
335	st->l3.global = NULL;
336	skb_queue_head_init(&st->l3.squeue);
337	st->l3.l3m.fsm = &l3fsm;
338	st->l3.l3m.state = ST_L3_LC_REL;
339	st->l3.l3m.debug = 1;
340	st->l3.l3m.userdata = st;
341	st->l3.l3m.userint = 0;
342	st->l3.l3m.printdebug = l3m_debug;
343        FsmInitTimer(&st->l3.l3m, &st->l3.l3m_timer);
344	strcpy(st->l3.debug_id, "L3DC ");
345	st->lli.l4l3_proto = no_l3_proto_spec;
346
347#ifdef	CONFIG_HISAX_EURO
348	if (st->protocol == ISDN_PTYPE_EURO) {
349		setstack_dss1(st);
350	} else
351#endif
352#ifdef  CONFIG_HISAX_NI1
353	if (st->protocol == ISDN_PTYPE_NI1) {
354		setstack_ni1(st);
355	} else
356#endif
357#ifdef	CONFIG_HISAX_1TR6
358	if (st->protocol == ISDN_PTYPE_1TR6) {
359		setstack_1tr6(st);
360	} else
361#endif
362	if (st->protocol == ISDN_PTYPE_LEASED) {
363		st->lli.l4l3 = no_l3_proto;
364		st->l2.l2l3 = no_l3_proto;
365                st->l3.l3ml3 = no_l3_proto;
366		printk(KERN_INFO "HiSax: Leased line mode\n");
367	} else {
368		st->lli.l4l3 = no_l3_proto;
369		st->l2.l2l3 = no_l3_proto;
370                st->l3.l3ml3 = no_l3_proto;
371		sprintf(tmp, "protocol %s not supported",
372			(st->protocol == ISDN_PTYPE_1TR6) ? "1tr6" :
373			(st->protocol == ISDN_PTYPE_EURO) ? "euro" :
374			(st->protocol == ISDN_PTYPE_NI1) ? "ni1" :
375			"unknown");
376		printk(KERN_WARNING "HiSax: %s\n", tmp);
377		st->protocol = -1;
378	}
379}
380
381static void
382isdnl3_trans(struct PStack *st, int pr, void *arg) {
383	st->l3.l3l2(st, pr, arg);
384}
385
386void
387releasestack_isdnl3(struct PStack *st)
388{
389	while (st->l3.proc)
390		release_l3_process(st->l3.proc);
391	if (st->l3.global) {
392		StopAllL3Timer(st->l3.global);
393		kfree(st->l3.global);
394		st->l3.global = NULL;
395	}
396	FsmDelTimer(&st->l3.l3m_timer, 54);
397	skb_queue_purge(&st->l3.squeue);
398}
399
400void
401setstack_l3bc(struct PStack *st, struct Channel *chanp)
402{
403
404	st->l3.proc   = NULL;
405	st->l3.global = NULL;
406	skb_queue_head_init(&st->l3.squeue);
407	st->l3.l3m.fsm = &l3fsm;
408	st->l3.l3m.state = ST_L3_LC_REL;
409	st->l3.l3m.debug = 1;
410	st->l3.l3m.userdata = st;
411	st->l3.l3m.userint = 0;
412	st->l3.l3m.printdebug = l3m_debug;
413	strcpy(st->l3.debug_id, "L3BC ");
414	st->lli.l4l3 = isdnl3_trans;
415}
416
417#define DREL_TIMER_VALUE 40000
418
419static void
420lc_activate(struct FsmInst *fi, int event, void *arg)
421{
422	struct PStack *st = fi->userdata;
423
424	FsmChangeState(fi, ST_L3_LC_ESTAB_WAIT);
425	st->l3.l3l2(st, DL_ESTABLISH | REQUEST, NULL);
426}
427
428static void
429lc_connect(struct FsmInst *fi, int event, void *arg)
430{
431	struct PStack *st = fi->userdata;
432	struct sk_buff *skb = arg;
433	int dequeued = 0;
434
435	FsmChangeState(fi, ST_L3_LC_ESTAB);
436	while ((skb = skb_dequeue(&st->l3.squeue))) {
437		st->l3.l3l2(st, DL_DATA | REQUEST, skb);
438		dequeued++;
439	}
440	if ((!st->l3.proc) &&  dequeued) {
441		if (st->l3.debug)
442			l3_debug(st, "lc_connect: release link");
443		FsmEvent(&st->l3.l3m, EV_RELEASE_REQ, NULL);
444	} else
445		l3ml3p(st, DL_ESTABLISH | INDICATION);
446}
447
448static void
449lc_connected(struct FsmInst *fi, int event, void *arg)
450{
451	struct PStack *st = fi->userdata;
452	struct sk_buff *skb = arg;
453	int dequeued = 0;
454
455	FsmDelTimer(&st->l3.l3m_timer, 51);
456	FsmChangeState(fi, ST_L3_LC_ESTAB);
457	while ((skb = skb_dequeue(&st->l3.squeue))) {
458		st->l3.l3l2(st, DL_DATA | REQUEST, skb);
459		dequeued++;
460	}
461	if ((!st->l3.proc) &&  dequeued) {
462		if (st->l3.debug)
463			l3_debug(st, "lc_connected: release link");
464		FsmEvent(&st->l3.l3m, EV_RELEASE_REQ, NULL);
465	} else
466		l3ml3p(st, DL_ESTABLISH | CONFIRM);
467}
468
469static void
470lc_start_delay(struct FsmInst *fi, int event, void *arg)
471{
472       struct PStack *st = fi->userdata;
473
474       FsmChangeState(fi, ST_L3_LC_REL_DELAY);
475       FsmAddTimer(&st->l3.l3m_timer, DREL_TIMER_VALUE, EV_TIMEOUT, NULL, 50);
476}
477
478static void
479lc_start_delay_check(struct FsmInst *fi, int event, void *arg)
480/* 20/09/00 - GE timer not user for NI-1 as layer 2 should stay up */
481{
482       struct PStack *st = fi->userdata;
483
484       FsmChangeState(fi, ST_L3_LC_REL_DELAY);
485       /* 19/09/00 - GE timer not user for NI-1 */
486       if (st->protocol != ISDN_PTYPE_NI1)
487       		FsmAddTimer(&st->l3.l3m_timer, DREL_TIMER_VALUE, EV_TIMEOUT, NULL, 50);
488}
489
490static void
491lc_release_req(struct FsmInst *fi, int event, void *arg)
492{
493	struct PStack *st = fi->userdata;
494
495	if (test_bit(FLG_L2BLOCK, &st->l2.flag)) {
496		if (st->l3.debug)
497			l3_debug(st, "lc_release_req: l2 blocked");
498		/* restart release timer */
499		FsmAddTimer(&st->l3.l3m_timer, DREL_TIMER_VALUE, EV_TIMEOUT, NULL, 51);
500	} else {
501		FsmChangeState(fi, ST_L3_LC_REL_WAIT);
502		st->l3.l3l2(st, DL_RELEASE | REQUEST, NULL);
503	}
504}
505
506static void
507lc_release_ind(struct FsmInst *fi, int event, void *arg)
508{
509	struct PStack *st = fi->userdata;
510
511	FsmDelTimer(&st->l3.l3m_timer, 52);
512	FsmChangeState(fi, ST_L3_LC_REL);
513	skb_queue_purge(&st->l3.squeue);
514	l3ml3p(st, DL_RELEASE | INDICATION);
515}
516
517static void
518lc_release_cnf(struct FsmInst *fi, int event, void *arg)
519{
520	struct PStack *st = fi->userdata;
521
522	FsmChangeState(fi, ST_L3_LC_REL);
523	skb_queue_purge(&st->l3.squeue);
524	l3ml3p(st, DL_RELEASE | CONFIRM);
525}
526
527
528/* *INDENT-OFF* */
529static struct FsmNode L3FnList[] __initdata =
530{
531	{ST_L3_LC_REL,		EV_ESTABLISH_REQ,	lc_activate},
532	{ST_L3_LC_REL,		EV_ESTABLISH_IND,	lc_connect},
533	{ST_L3_LC_REL,		EV_ESTABLISH_CNF,	lc_connect},
534	{ST_L3_LC_ESTAB_WAIT,	EV_ESTABLISH_CNF,	lc_connected},
535	{ST_L3_LC_ESTAB_WAIT,	EV_RELEASE_REQ,		lc_start_delay},
536	{ST_L3_LC_ESTAB_WAIT,	EV_RELEASE_IND,		lc_release_ind},
537	{ST_L3_LC_ESTAB,	EV_RELEASE_IND,		lc_release_ind},
538	{ST_L3_LC_ESTAB,	EV_RELEASE_REQ,		lc_start_delay_check},
539        {ST_L3_LC_REL_DELAY,    EV_RELEASE_IND,         lc_release_ind},
540        {ST_L3_LC_REL_DELAY,    EV_ESTABLISH_REQ,       lc_connected},
541        {ST_L3_LC_REL_DELAY,    EV_TIMEOUT,             lc_release_req},
542	{ST_L3_LC_REL_WAIT,	EV_RELEASE_CNF,		lc_release_cnf},
543	{ST_L3_LC_REL_WAIT,	EV_ESTABLISH_REQ,	lc_activate},
544};
545/* *INDENT-ON* */
546
547void
548l3_msg(struct PStack *st, int pr, void *arg)
549{
550	switch (pr) {
551		case (DL_DATA | REQUEST):
552			if (st->l3.l3m.state == ST_L3_LC_ESTAB) {
553				st->l3.l3l2(st, pr, arg);
554			} else {
555				struct sk_buff *skb = arg;
556
557				skb_queue_tail(&st->l3.squeue, skb);
558				FsmEvent(&st->l3.l3m, EV_ESTABLISH_REQ, NULL);
559			}
560			break;
561		case (DL_ESTABLISH | REQUEST):
562			FsmEvent(&st->l3.l3m, EV_ESTABLISH_REQ, NULL);
563			break;
564		case (DL_ESTABLISH | CONFIRM):
565			FsmEvent(&st->l3.l3m, EV_ESTABLISH_CNF, NULL);
566			break;
567		case (DL_ESTABLISH | INDICATION):
568			FsmEvent(&st->l3.l3m, EV_ESTABLISH_IND, NULL);
569			break;
570		case (DL_RELEASE | INDICATION):
571			FsmEvent(&st->l3.l3m, EV_RELEASE_IND, NULL);
572			break;
573		case (DL_RELEASE | CONFIRM):
574			FsmEvent(&st->l3.l3m, EV_RELEASE_CNF, NULL);
575			break;
576		case (DL_RELEASE | REQUEST):
577			FsmEvent(&st->l3.l3m, EV_RELEASE_REQ, NULL);
578			break;
579	}
580}
581
582int __init
583Isdnl3New(void)
584{
585	l3fsm.state_count = L3_STATE_COUNT;
586	l3fsm.event_count = L3_EVENT_COUNT;
587	l3fsm.strEvent = strL3Event;
588	l3fsm.strState = strL3State;
589	return FsmNew(&l3fsm, L3FnList, ARRAY_SIZE(L3FnList));
590}
591
592void
593Isdnl3Free(void)
594{
595	FsmFree(&l3fsm);
596}
597