tei.c 11.1 KB
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 assigned 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);
}