aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/isdn/hisax/tei.c
blob: 842f9c9e875dbb1c647e7737c470ed99e5077935 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
/* $Id: tei.c,v 2.20.2.3 2004/01/13 14:31:26 keil Exp $
 *
 * Author       Karsten Keil
 *              based on the teles driver from Jan den Ouden
 * Copyright    by Karsten Keil      <keil@isdn4linux.de>
 * 
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 *
 * For changes and modifications please read
 * Documentation/isdn/HiSax.cert
 *
 * Thanks to    Jan den Ouden
 *              Fritz Elfert
 *
 */

#include "hisax.h"
#include "isdnl2.h"
#include <linux/gfp.h>
#include <linux/init.h>
#include <linux/random.h>

const char *tei_revision = "$Revision: 2.20.2.3 $";

#define ID_REQUEST	1
#define ID_ASSIGNED	2
#define ID_DENIED	3
#define ID_CHK_REQ	4
#define ID_CHK_RES	5
#define ID_REMOVE	6
#define ID_VERIFY	7

#define TEI_ENTITY_ID	0xf

static struct Fsm teifsm;

void tei_handler(struct PStack *st, u_char pr, struct sk_buff *skb);

enum {
	ST_TEI_NOP,
	ST_TEI_IDREQ,
	ST_TEI_IDVERIFY,
};

#define TEI_STATE_COUNT (ST_TEI_IDVERIFY+1)

static char *strTeiState[] =
{
	"ST_TEI_NOP",
	"ST_TEI_IDREQ",
	"ST_TEI_IDVERIFY",
};

enum {
	EV_IDREQ,
	EV_ASSIGN,
	EV_DENIED,
	EV_CHKREQ,
	EV_REMOVE,
	EV_VERIFY,
	EV_T202,
};

#define TEI_EVENT_COUNT (EV_T202+1)

static char *strTeiEvent[] =
{
	"EV_IDREQ",
	"EV_ASSIGN",
	"EV_DENIED",
	"EV_CHKREQ",
	"EV_REMOVE",
	"EV_VERIFY",
	"EV_T202",
};

static unsigned int
random_ri(void)
{
	unsigned int x;

	get_random_bytes(&x, sizeof(x));
	return (x & 0xffff);
}

static struct PStack *
findtei(struct PStack *st, int tei)
{
	struct PStack *ptr = *(st->l1.stlistp);

	if (tei == 127)
		return (NULL);

	while (ptr)
		if (ptr->l2.tei == tei)
			return (ptr);
		else
			ptr = ptr->next;
	return (NULL);
}

static void
put_tei_msg(struct PStack *st, u_char m_id, unsigned int ri, u_char tei)
{
	struct sk_buff *skb;
	u_char *bp;

	if (!(skb = alloc_skb(8, GFP_ATOMIC))) {
		printk(KERN_WARNING "HiSax: No skb for TEI manager\n");
		return;
	}
	bp = skb_put(skb, 3);
	bp[0] = (TEI_SAPI << 2);
	bp[1] = (GROUP_TEI << 1) | 0x1;
	bp[2] = UI;
	bp = skb_put(skb, 5);
	bp[0] = TEI_ENTITY_ID;
	bp[1] = ri >> 8;
	bp[2] = ri & 0xff;
	bp[3] = m_id;
	bp[4] = (tei << 1) | 1;
	st->l2.l2l1(st, PH_DATA | REQUEST, skb);
}

static void
tei_id_request(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;

	if (st->l2.tei != -1) {
		st->ma.tei_m.printdebug(&st->ma.tei_m,
			"assign request for already asigned tei %d",
			st->l2.tei);
		return;
	}
	st->ma.ri = random_ri();
	if (st->ma.debug)
		st->ma.tei_m.printdebug(&st->ma.tei_m,
			"assign request ri %d", st->ma.ri);
	put_tei_msg(st, ID_REQUEST, st->ma.ri, 127);
	FsmChangeState(&st->ma.tei_m, ST_TEI_IDREQ);
	FsmAddTimer(&st->ma.t202, st->ma.T202, EV_T202, NULL, 1);
	st->ma.N202 = 3;
}

static void
tei_id_assign(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *ost, *st = fi->userdata;
	struct sk_buff *skb = arg;
	struct IsdnCardState *cs;
	int ri, tei;

	ri = ((unsigned int) skb->data[1] << 8) + skb->data[2];
	tei = skb->data[4] >> 1;
	if (st->ma.debug)
		st->ma.tei_m.printdebug(&st->ma.tei_m,
			"identity assign ri %d tei %d", ri, tei);
	if ((ost = findtei(st, tei))) {	/* same tei is in use */
		if (ri != ost->ma.ri) {
			st->ma.tei_m.printdebug(&st->ma.tei_m,
				"possible duplicate assignment tei %d", tei);
			ost->l2.l2tei(ost, MDL_ERROR | RESPONSE, NULL);
		}
	} else if (ri == st->ma.ri) {
		FsmDelTimer(&st->ma.t202, 1);
		FsmChangeState(&st->ma.tei_m, ST_TEI_NOP);
		st->l3.l3l2(st, MDL_ASSIGN | REQUEST, (void *) (long) tei);
		cs = (struct IsdnCardState *) st->l1.hardware;
		cs->cardmsg(cs, MDL_ASSIGN | REQUEST, NULL);
	}
}

static void
tei_id_test_dup(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *ost, *st = fi->userdata;
	struct sk_buff *skb = arg;
	int tei, ri;

	ri = ((unsigned int) skb->data[1] << 8) + skb->data[2];
	tei = skb->data[4] >> 1;
	if (st->ma.debug)
		st->ma.tei_m.printdebug(&st->ma.tei_m,
			"foreign identity assign ri %d tei %d", ri, tei);
	if ((ost = findtei(st, tei))) {	/* same tei is in use */
		if (ri != ost->ma.ri) {	/* and it wasn't our request */
			st->ma.tei_m.printdebug(&st->ma.tei_m,
				"possible duplicate assignment tei %d", tei);
			FsmEvent(&ost->ma.tei_m, EV_VERIFY, NULL);
		}
	} 
}

static void
tei_id_denied(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;
	int ri, tei;

	ri = ((unsigned int) skb->data[1] << 8) + skb->data[2];
	tei = skb->data[4] >> 1;
	if (st->ma.debug)
		st->ma.tei_m.printdebug(&st->ma.tei_m,
			"identity denied ri %d tei %d", ri, tei);
}

static void
tei_id_chk_req(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;
	int tei;

	tei = skb->data[4] >> 1;
	if (st->ma.debug)
		st->ma.tei_m.printdebug(&st->ma.tei_m,
			"identity check req tei %d", tei);
	if ((st->l2.tei != -1) && ((tei == GROUP_TEI) || (tei == st->l2.tei))) {
		FsmDelTimer(&st->ma.t202, 4);
		FsmChangeState(&st->ma.tei_m, ST_TEI_NOP);
		put_tei_msg(st, ID_CHK_RES, random_ri(), st->l2.tei);
	}
}

static void
tei_id_remove(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;
	struct IsdnCardState *cs;
	int tei;

	tei = skb->data[4] >> 1;
	if (st->ma.debug)
		st->ma.tei_m.printdebug(&st->ma.tei_m,
			"identity remove tei %d", tei);
	if ((st->l2.tei != -1) && ((tei == GROUP_TEI) || (tei == st->l2.tei))) {
		FsmDelTimer(&st->ma.t202, 5);
		FsmChangeState(&st->ma.tei_m, ST_TEI_NOP);
		st->l3.l3l2(st, MDL_REMOVE | REQUEST, NULL);
		cs = (struct IsdnCardState *) st->l1.hardware;
		cs->cardmsg(cs, MDL_REMOVE | REQUEST, NULL);
	}
}

static void
tei_id_verify(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;

	if (st->ma.debug)
		st->ma.tei_m.printdebug(&st->ma.tei_m,
			"id verify request for tei %d", st->l2.tei);
	put_tei_msg(st, ID_VERIFY, 0, st->l2.tei);
	FsmChangeState(&st->ma.tei_m, ST_TEI_IDVERIFY);
	FsmAddTimer(&st->ma.t202, st->ma.T202, EV_T202, NULL, 2);
	st->ma.N202 = 2;
}

static void
tei_id_req_tout(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct IsdnCardState *cs;

	if (--st->ma.N202) {
		st->ma.ri = random_ri();
		if (st->ma.debug)
			st->ma.tei_m.printdebug(&st->ma.tei_m,
				"assign req(%d) ri %d", 4 - st->ma.N202,
				st->ma.ri);
		put_tei_msg(st, ID_REQUEST, st->ma.ri, 127);
		FsmAddTimer(&st->ma.t202, st->ma.T202, EV_T202, NULL, 3);
	} else {
		st->ma.tei_m.printdebug(&st->ma.tei_m, "assign req failed");
		st->l3.l3l2(st, MDL_ERROR | RESPONSE, NULL);
		cs = (struct IsdnCardState *) st->l1.hardware;
		cs->cardmsg(cs, MDL_REMOVE | REQUEST, NULL);
		FsmChangeState(fi, ST_TEI_NOP);
	}
}

static void
tei_id_ver_tout(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct IsdnCardState *cs;

	if (--st->ma.N202) {
		if (st->ma.debug)
			st->ma.tei_m.printdebug(&st->ma.tei_m,
				"id verify req(%d) for tei %d",
				3 - st->ma.N202, st->l2.tei);
		put_tei_msg(st, ID_VERIFY, 0, st->l2.tei);
		FsmAddTimer(&st->ma.t202, st->ma.T202, EV_T202, NULL, 4);
	} else {
		st->ma.tei_m.printdebug(&st->ma.tei_m,
			"verify req for tei %d failed", st->l2.tei);
		st->l3.l3l2(st, MDL_REMOVE | REQUEST, NULL);
		cs = (struct IsdnCardState *) st->l1.hardware;
		cs->cardmsg(cs, MDL_REMOVE | REQUEST, NULL);
		FsmChangeState(fi, ST_TEI_NOP);
	}
}

static void
tei_l1l2(struct PStack *st, int pr, void *arg)
{
	struct sk_buff *skb = arg;
	int mt;

	if (test_bit(FLG_FIXED_TEI, &st->l2.flag)) {
		dev_kfree_skb(skb);
		return;
	}

	if (pr == (PH_DATA | INDICATION)) {
		if (skb->len < 3) {
			st->ma.tei_m.printdebug(&st->ma.tei_m,
				"short mgr frame %ld/3", skb->len);
		} else if ((skb->data[0] != ((TEI_SAPI << 2) | 2)) ||
			   (skb->data[1] != ((GROUP_TEI << 1) | 1))) {
			st->ma.tei_m.printdebug(&st->ma.tei_m,
				"wrong mgr sapi/tei %x/%x",
				skb->data[0], skb->data[1]);
		} else if ((skb->data[2] & 0xef) != UI) {
			st->ma.tei_m.printdebug(&st->ma.tei_m,
				"mgr frame is not ui %x", skb->data[2]);
		} else {
			skb_pull(skb, 3);
			if (skb->len < 5) {
				st->ma.tei_m.printdebug(&st->ma.tei_m,
					"short mgr frame %ld/5", skb->len);
			} else if (skb->data[0] != TEI_ENTITY_ID) {
				/* wrong management entity identifier, ignore */
				st->ma.tei_m.printdebug(&st->ma.tei_m,
					"tei handler wrong entity id %x",
					skb->data[0]);
			} else {
				mt = skb->data[3];
				if (mt == ID_ASSIGNED)
					FsmEvent(&st->ma.tei_m, EV_ASSIGN, skb);
				else if (mt == ID_DENIED)
					FsmEvent(&st->ma.tei_m, EV_DENIED, skb);
				else if (mt == ID_CHK_REQ)
					FsmEvent(&st->ma.tei_m, EV_CHKREQ, skb);
				else if (mt == ID_REMOVE)
					FsmEvent(&st->ma.tei_m, EV_REMOVE, skb);
				else {
					st->ma.tei_m.printdebug(&st->ma.tei_m,
						"tei handler wrong mt %x\n", mt);
				}
			}
		}
	} else {
		st->ma.tei_m.printdebug(&st->ma.tei_m,
			"tei handler wrong pr %x\n", pr);
	}
	dev_kfree_skb(skb);
}

static void
tei_l2tei(struct PStack *st, int pr, void *arg)
{
	struct IsdnCardState *cs;

	if (test_bit(FLG_FIXED_TEI, &st->l2.flag)) {
		if (pr == (MDL_ASSIGN | INDICATION)) {
			if (st->ma.debug)
				st->ma.tei_m.printdebug(&st->ma.tei_m,
					"fixed assign tei %d", st->l2.tei);
			st->l3.l3l2(st, MDL_ASSIGN | REQUEST, (void *) (long) st->l2.tei);
			cs = (struct IsdnCardState *) st->l1.hardware;
			cs->cardmsg(cs, MDL_ASSIGN | REQUEST, NULL);
		}
		return;
	}
	switch (pr) {
		case (MDL_ASSIGN | INDICATION):
			FsmEvent(&st->ma.tei_m, EV_IDREQ, arg);
			break;
		case (MDL_ERROR | REQUEST):
			FsmEvent(&st->ma.tei_m, EV_VERIFY, arg);
			break;
		default:
			break;
	}
}

static void
tei_debug(struct FsmInst *fi, char *fmt, ...)
{
	va_list args;
	struct PStack *st = fi->userdata;

	va_start(args, fmt);
	VHiSax_putstatus(st->l1.hardware, "tei ", fmt, args);
	va_end(args);
}

void
setstack_tei(struct PStack *st)
{
	st->l2.l2tei = tei_l2tei;
	st->ma.T202 = 2000;	/* T202  2000 milliseconds */
	st->l1.l1tei = tei_l1l2;
	st->ma.debug = 1;
	st->ma.tei_m.fsm = &teifsm;
	st->ma.tei_m.state = ST_TEI_NOP;
	st->ma.tei_m.debug = 1;
	st->ma.tei_m.userdata = st;
	st->ma.tei_m.userint = 0;
	st->ma.tei_m.printdebug = tei_debug;
	FsmInitTimer(&st->ma.tei_m, &st->ma.t202);
}

void
init_tei(struct IsdnCardState *cs, int protocol)
{
}

void
release_tei(struct IsdnCardState *cs)
{
	struct PStack *st = cs->stlist;

	while (st) {
		FsmDelTimer(&st->ma.t202, 1);
		st = st->next;
	}
}

static struct FsmNode TeiFnList[] __initdata =
{
	{ST_TEI_NOP, EV_IDREQ, tei_id_request},
	{ST_TEI_NOP, EV_ASSIGN, tei_id_test_dup},
	{ST_TEI_NOP, EV_VERIFY, tei_id_verify},
	{ST_TEI_NOP, EV_REMOVE, tei_id_remove},
	{ST_TEI_NOP, EV_CHKREQ, tei_id_chk_req},
	{ST_TEI_IDREQ, EV_T202, tei_id_req_tout},
	{ST_TEI_IDREQ, EV_ASSIGN, tei_id_assign},
	{ST_TEI_IDREQ, EV_DENIED, tei_id_denied},
	{ST_TEI_IDVERIFY, EV_T202, tei_id_ver_tout},
	{ST_TEI_IDVERIFY, EV_REMOVE, tei_id_remove},
	{ST_TEI_IDVERIFY, EV_CHKREQ, tei_id_chk_req},
};

int __init
TeiNew(void)
{
	teifsm.state_count = TEI_STATE_COUNT;
	teifsm.event_count = TEI_EVENT_COUNT;
	teifsm.strEvent = strTeiEvent;
	teifsm.strState = strTeiState;
	return FsmNew(&teifsm, TeiFnList, ARRAY_SIZE(TeiFnList));
}

void
TeiFree(void)
{
	FsmFree(&teifsm);
}