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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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 | /* $Id: isdn_v110.c,v 1.2 1998/02/22 19:44:25 fritz Exp $ * Linux ISDN subsystem, V.110 related functions (linklevel). * * Copyright by Thomas Pfeiffer (pfeiffer@pds.de) * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * * $Log: isdn_v110.c,v $ * Revision 1.2 1998/02/22 19:44:25 fritz * Bugfixes and improvements regarding V.110, V.110 now running. * * Revision 1.1 1998/02/20 17:32:09 fritz * First checkin (not yet completely functionable). * */ #include <linux/string.h> #include <linux/kernel.h> #include <linux/malloc.h> #include <linux/mm.h> #include <linux/isdn.h> #include "isdn_v110.h" #undef ISDN_V110_DEBUG char *isdn_v110_revision = "$Revision: 1.2 $"; #define V110_38400 255 #define V110_19200 15 #define V110_9600 3 /* Die folgenden Daten sind fertig kodierte Matrizen, jeweils als online und offline matrix für 9600, 19200 und 38400 */ static unsigned char V110_OnMatrix_9600[] = {0xfc, 0xfc, 0xfc, 0xfc, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff, 0xff, 0xfd, 0xfd, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff, 0xff, 0xfd}; static unsigned char V110_OffMatrix_9600[] = {0xfc, 0xfc, 0xfc, 0xfc, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; static unsigned char V110_OnMatrix_19200[] = {0xf0, 0xf0, 0xff, 0xf7, 0xff, 0xf7, 0xff, 0xf7, 0xff, 0xf7, 0xfd, 0xff, 0xff, 0xf7, 0xff, 0xf7, 0xff, 0xf7, 0xff, 0xf7}; static unsigned char V110_OffMatrix_19200[] = {0xf0, 0xf0, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; static unsigned char V110_OnMatrix_38400[] = {0x00, 0x7f, 0x7f, 0x7f, 0x7f, 0xfd, 0x7f, 0x7f, 0x7f, 0x7f}; static unsigned char V110_OffMatrix_38400[] = {0x00, 0xff, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff, 0xff, 0xff}; /* FlipBits dreht die Reihenfolge von jeweils keylen bits in einem byte um. Aus der Bitreihenfolge 76543210 werden bei keylen=4 die bits 45670123, bei keylen=2 die bits 67452301. Dies ist notwendig, weil die reihenfolge auf der isdn-leitung falsch herum ist. */ static __inline unsigned char FlipBits(unsigned char c, int keylen) { unsigned char b = c; unsigned char bit = 128; int i; int j; int hunks = (8 / keylen); c = 0; for (i = 0; i < hunks; i++) { for (j = 0; j < keylen; j++) { if (b & (bit >> j)) c |= bit >> (keylen - j - 1); } bit >>= keylen; } return c; } /* isdn_v110_open allocates and initializes private V.110 data * structures and returns a pointer to these. */ static isdn_v110_stream * isdn_v110_open(unsigned char key, int hdrlen, int maxsize) { int i; isdn_v110_stream *v; if ((v = kmalloc(sizeof(isdn_v110_stream), GFP_KERNEL)) == NULL) return NULL; memset(v, 0, sizeof(isdn_v110_stream)); v->key = key; v->nbits = 0; for (i = 0; key & (1 << i); i++) v->nbits++; v->nbytes = 8 / v->nbits; v->decodelen = 0; switch (key) { case V110_38400: v->OnlineFrame = V110_OnMatrix_38400; v->OfflineFrame = V110_OffMatrix_38400; break; case V110_19200: v->OnlineFrame = V110_OnMatrix_19200; v->OfflineFrame = V110_OffMatrix_19200; break; default: v->OnlineFrame = V110_OnMatrix_9600; v->OfflineFrame = V110_OffMatrix_9600; break; } v->framelen = v->nbytes * 10; v->SyncInit = 5; v->introducer = 0; v->dbit = 1; v->b = 0; v->skbres = hdrlen; v->maxsize = maxsize - hdrlen; if ((v->encodebuf = kmalloc(maxsize, GFP_KERNEL)) == NULL) { kfree(v); return NULL; } return v; } /* isdn_v110_close frees private V.110 data structures */ static void isdn_v110_close(isdn_v110_stream * v) { if (v == NULL) return; #ifdef ISDN_V110_DEBUG printk(KERN_DEBUG "v110 close\n"); #if 0 printk(KERN_DEBUG "isdn_v110_close: nbytes=%d\n", v->nbytes); printk(KERN_DEBUG "isdn_v110_close: nbits=%d\n", v->nbits); printk(KERN_DEBUG "isdn_v110_close: key=%d\n", v->key); printk(KERN_DEBUG "isdn_v110_close: SyncInit=%d\n", v->SyncInit); printk(KERN_DEBUG "isdn_v110:close: decodelen=%d\n", v->decodelen); printk(KERN_DEBUG "isdn_v110_close: framelen=%d\n", v->framelen); #endif #endif kfree(v->encodebuf); kfree(v); } /* ValidHeaderBytes prüft, wieviele bytes in v->decodebuf gültig sind */ static int ValidHeaderBytes(isdn_v110_stream * v) { int i; for (i = 0; (i < v->decodelen) && (i < v->nbytes); i++) if ((v->decodebuf[i] & v->key) != 0) break; return i; } /* SyncHeader schiebt den decodebuf pointer auf den nächsten gültigen header */ static void SyncHeader(isdn_v110_stream * v) { unsigned char *rbuf = v->decodebuf; int len = v->decodelen; if (len == 0) return; for (rbuf++, len--; len > 0; len--, rbuf++) /* such den SyncHeader in buf ! */ if ((*rbuf & v->key) == 0) /* erstes byte gefunden ? */ break; /* jupp! */ if (len) memcpy(v->decodebuf, rbuf, len); v->decodelen = len; #ifdef ISDN_V110_DEBUG printk(KERN_DEBUG "isdn_v110: Header resync\n"); #endif } /* DecodeMatrix takes n (n>=1) matrices (v110 frames, 10 bytes) where len is the number of matrix-lines. len must be a multiple of 10, i.e. only complete matices must be given. From these, netto data is extracted and returned in buf. The return-value is the bytecount of the decoded data. */ static int DecodeMatrix(isdn_v110_stream * v, unsigned char *m, int len, unsigned char *buf) { int line = 0; int buflen = 0; int mbit = 64; int introducer = v->introducer; int dbit = v->dbit; unsigned char b = v->b; while (line < len) { /* sind schon alle matrizenzeilen abgearbeitet? */ if ((line % 10) == 0) { /* die 0. zeile der matrix ist immer null ! */ if (m[line] != 0x00) { /* nicht 0 ? dann fehler! */ #ifdef ISDN_V110_DEBUG printk(KERN_DEBUG "isdn_v110: DecodeMatrix, V110 Bad Header\n"); #endif /* dann einen return zu machen, ist auch irgendwie nicht das richtige! :-( v->introducer = 0; v->dbit = 1; v->b = 0; return buflen; anzahl schon erzeugter daten zurückgeben! */ } line++; /* sonst die nächste matrixzeile nehmen */ continue; } else if ((line % 10) == 5) { /* in zeile 5 stehen nur e-bits ! */ if ((m[line] & 0x70) != 0x30) { /* 011 muß am anfang stehen! */ #ifdef ISDN_V110_DEBUG printk(KERN_DEBUG "isdn_v110: DecodeMatrix, V110 Bad 5th line\n"); #endif /* dann einen return zu machen, ist auch irgendwie nicht das richtige! :-( v->introducer = 0; v->dbit = 1; v->b = 0; return buflen; */ } line++; /* alles klar, nächste zeile */ continue; } else if (!introducer) { /* every byte starts with 10 (stopbit, startbit) */ introducer = (m[line] & mbit) ? 0 : 1; /* aktuelles bit der matrix */ next_byte: if (mbit > 2) { /* war es das letzte bit dieser matrixzeile ? */ mbit >>= 1; /* nein, nimm das nächste in dieser zeile */ continue; } /* sonst links in der nächsten zeile anfangen */ mbit = 64; line++; continue; } else { /* sonst müssen wir ein datenbit setzen */ if (m[line] & mbit) /* war das bit in der matrix gesetzt ? */ b |= dbit; /* ja, dann setz es auch im datenbyte */ else b &= dbit - 1; /* nein, lösch bit im datenbyte */ if (dbit < 128) /* haben wir schon ein ganzes byte voll ? */ dbit <<= 1; /* nein, auf zum nächsten datenbit */ else { /* ein ganzes datenbyte ist voll */ buf[buflen++] = b; /* byte in den output buffer kopieren */ introducer = b = 0; /* Init der Introsequenz und des datenbytes */ dbit = 1; /* als nächstes suchen wir das nullte bit */ } goto next_byte; /* suche das nächste bit in der matrix */ } } v->introducer = introducer; v->dbit = dbit; v->b = b; return buflen; /* return anzahl der bytes im output buffer */ } /* DecodeStream erhält vom input stream V110 kodierte Daten, die zu den V110 frames zusammengepackt werden müssen. Die Daten können an diese Schnittstelle so übergeben werden, wie sie von der Leitung kommen, ohne darauf achten zu müssen, das frames usw. eingehalten werden. */ struct sk_buff * isdn_v110_decode(isdn_v110_stream * v, struct sk_buff *skb) { int i; int j; int len; unsigned char *v110_buf; unsigned char *rbuf; if (!skb) { printk(KERN_WARNING "isdn_v110_decode called with NULL skb!\n"); return NULL; } rbuf = skb->data; len = skb->len; if (v == NULL) { /* invalid handle, no chance to proceed */ printk(KERN_WARNING "isdn_v110_decode called with NULL stream!\n"); dev_kfree_skb(skb); return NULL; } if (v->decodelen == 0) /* cache empty? */ for (; len > 0; len--, rbuf++) /* scan for SyncHeader in buf */ if ((*rbuf & v->key) == 0) break; /* found first byte */ if (len == 0) { dev_kfree_skb(skb); return NULL; } /* copy new data to decode-buffer */ memcpy(&(v->decodebuf[v->decodelen]), rbuf, len); v->decodelen += len; ReSync: if (v->decodelen < v->nbytes) { /* got a new header ? */ dev_kfree_skb(skb); return NULL; /* no, try later */ } if (ValidHeaderBytes(v) != v->nbytes) { /* ist es ein ungültiger header ? */ SyncHeader(v); /* nein, such einen header */ goto ReSync; } len = (v->decodelen - (v->decodelen % (10 * v->nbytes))) / v->nbytes; if ((v110_buf = kmalloc(len, GFP_ATOMIC)) == NULL) { printk(KERN_WARNING "isdn_v110_decode: Couldn't allocate v110_buf\n"); dev_kfree_skb(skb); return NULL; } for (i = 0; i < len; i++) { v110_buf[i] = 0; for (j = 0; j < v->nbytes; j++) v110_buf[i] |= (v->decodebuf[(i * v->nbytes) + j] & v->key) << (8 - ((j + 1) * v->nbits)); v110_buf[i] = FlipBits(v110_buf[i], v->nbits); } v->decodelen = (v->decodelen % (10 * v->nbytes)); memcpy(v->decodebuf, &(v->decodebuf[len * v->nbytes]), v->decodelen); skb_trim(skb, DecodeMatrix(v, v110_buf, len, skb->data)); kfree(v110_buf); if (skb->len) return skb; else { kfree_skb(skb); return NULL; } } /* EncodeMatrix takes input data in buf, len is the bytecount. Data is encoded into v110 frames in m. Return value is the number of matrix-lines generated. */ static int EncodeMatrix(unsigned char *buf, int len, unsigned char *m, int mlen) { int line = 0; int i = 0; int mbit = 128; int dbit = 1; int introducer = 3; int ibit[] = {0, 1, 1}; while ((i < len) && (line < mlen)) { /* solange noch input da ist */ switch (line % 10) { /* in welcher matrixzeile sind wir ? */ case 0: m[line++] = 0x00; /* zeile 0 ist immer 0 */ mbit = 128; /* und es geht mit dem 7. bit weiter */ break; case 5: m[line++] = 0xbf; /* zeile 5 ist immer 10111111 */ mbit = 128; /* und es geht mit dem 7. bit weiter */ break; } if (line >= mlen) { printk(KERN_WARNING "isdn_v110 (EncodeMatrix): buffer full!\n"); return line; } next_bit: switch (mbit) { /* ganz linkes oder rechtes bit ? */ case 1: line++; /* ganz rechts ! dann in die nächste */ if (line >= mlen) { printk(KERN_WARNING "isdn_v110 (EncodeMatrix): buffer full!\n"); return line; } case 128: m[line] = 128; /* ganz links byte auf 1000000 setzen */ mbit = 64; /* aktuelles bit in der matrixzeile */ continue; } if (introducer) { /* 110 sequenz setzen ? */ introducer--; /* ein digit weniger setzen */ m[line] |= ibit[introducer] ? mbit : 0; /* entsprechendes bit setzen */ mbit >>= 1; /* bit der matrixzeile >> 1 */ goto next_bit; /* und dort weiter machen */ } /* else datenbits in die matrix packen! */ m[line] |= (buf[i] & dbit) ? mbit : 0; /* datenbit in matrix setzen */ if (dbit == 128) { /* war es das letzte datenbit ? */ dbit = 1; /* dann mach beim nächsten weiter */ i++; /* nächste datenbyte des input buffers */ if (i < len) /* war es schon das letzte ? */ introducer = 3; /* nein, schreib den introducer 110 */ else { /* war das letzte datenbyte ! */ m[line] |= (mbit - 1) & 0xfe; /* setz restliche bits der zeile auf 1 */ break; } } else /* nicht das letzte datenbit */ dbit <<= 1; /* dann gehe zum nächsten datenbit */ mbit >>= 1; /* und setz bit der matrix weiter */ goto next_bit; } /* evtl. noch restliche zeilen in der matrix generieren... */ if ((line) && ((line + 10) < mlen)) switch (++line % 10) { case 1: m[line++] = 0xfe; case 2: m[line++] = 0xfe; case 3: m[line++] = 0xfe; case 4: m[line++] = 0xfe; case 5: m[line++] = 0xbf; case 6: m[line++] = 0xfe; case 7: m[line++] = 0xfe; case 8: m[line++] = 0xfe; case 9: m[line++] = 0xfe; } return line; /* soviele matrixzeilen sind es */ } /* * Build a sync frame. */ static struct sk_buff * isdn_v110_sync(isdn_v110_stream *v) { struct sk_buff *skb; if (v == NULL) { /* invalid handle, no chance to proceed */ printk(KERN_WARNING "isdn_v110_sync called with NULL stream!\n"); return NULL; } if ((skb = dev_alloc_skb(v->framelen + v->skbres))) { skb_reserve(skb, v->skbres); memcpy(skb_put(skb, v->framelen), v->OfflineFrame, v->framelen); } return skb; } /* * Build an idle frame. */ static struct sk_buff * isdn_v110_idle(isdn_v110_stream *v) { struct sk_buff *skb; if (v == NULL) { /* invalid handle, no chance to proceed */ printk(KERN_WARNING "isdn_v110_sync called with NULL stream!\n"); return NULL; } if ((skb = dev_alloc_skb(v->framelen + v->skbres))) { skb_reserve(skb, v->skbres); memcpy(skb_put(skb, v->framelen), v->OnlineFrame, v->framelen); } return skb; } struct sk_buff * isdn_v110_encode(isdn_v110_stream * v, struct sk_buff *skb) { int i; int j; int rlen; int mlen; int olen; int size; int sval1; int sval2; int nframes; unsigned char *v110buf; unsigned char *rbuf; struct sk_buff *nskb; if (v == NULL) { /* invalid handle, no chance to proceed */ printk(KERN_WARNING "isdn_v110_encode called with NULL stream!\n"); return NULL; } if (!skb) { /* invalid skb, no chance to proceed */ printk(KERN_WARNING "isdn_v110_encode called with NULL skb!\n"); return NULL; } rlen = skb->len; nframes = (rlen + 3) / 4; v110buf = v->encodebuf; if ((nframes * 40) > v->maxsize) { size = v->maxsize; rlen = v->maxsize / 40; } else size = nframes * 40; if (!(nskb = dev_alloc_skb(size + v->skbres + sizeof(int)))) { printk(KERN_WARNING "isdn_v110_encode: Couldn't alloc skb\n"); return NULL; } skb_reserve(nskb, v->skbres + sizeof(int)); if (skb->len == 0) { memcpy(skb_put(nskb, v->framelen), v->OnlineFrame, v->framelen); *((int *)skb_push(nskb, sizeof(int))) = 0; return nskb; } mlen = EncodeMatrix(skb->data, rlen, v110buf, size); /* jetzt noch jeweils 2 oder 4 bits auf den output stream verteilen! */ rbuf = skb_put(nskb, size); olen = 0; sval1 = 8 - v->nbits; sval2 = v->key << sval1; for (i = 0; i < mlen; i++) { v110buf[i] = FlipBits(v110buf[i], v->nbits); for (j = 0; j < v->nbytes; j++) { if (size--) *rbuf++ = ~v->key | (((v110buf[i] << (j * v->nbits)) & sval2) >> sval1); else { printk(KERN_WARNING "isdn_v110_encode: buffers full!\n"); goto buffer_full; } olen++; } } buffer_full: skb_trim(nskb, olen); *((int *)skb_push(nskb, sizeof(int))) = rlen; return nskb; } int isdn_v110_stat_callback(int idx, isdn_ctrl * c) { isdn_v110_stream *v = NULL; int i; int ret; if (idx < 0) return 0; switch (c->command) { case ISDN_STAT_BSENT: /* Keep the send-queue of the driver filled * with frames: * If number of outstanding frames < 3, * send down an Idle-Frame (or an Sync-Frame, if * v->SyncInit != 0). */ if (!(v = dev->v110[idx])) return 0; atomic_inc(&dev->v110use[idx]); if (v->skbidle > 0) { v->skbidle--; ret = 1; } else { if (v->skbuser > 0) v->skbuser--; ret = 0; } for (i = v->skbuser + v->skbidle; i < 2; i++) { struct sk_buff *skb; if (v->SyncInit > 0) skb = isdn_v110_sync(v); else skb = isdn_v110_idle(v); if (skb) { if (dev->drv[c->driver]->interface->writebuf_skb(c->driver, c->arg, 1, skb) <= 0) { dev_kfree_skb(skb); break; } else { if (v->SyncInit) v->SyncInit--; v->skbidle++; } } else break; } atomic_dec(&dev->v110use[idx]); return ret; case ISDN_STAT_DHUP: case ISDN_STAT_BHUP: while (1) { atomic_inc(&dev->v110use[idx]); if (atomic_dec_and_test(&dev->v110use[idx])) { isdn_v110_close(dev->v110[idx]); dev->v110[idx] = NULL; break; } sti(); } break; case ISDN_STAT_BCONN: if (dev->v110emu[idx] && (dev->v110[idx] == NULL)) { int hdrlen = dev->drv[c->driver]->interface->hl_hdrlen; int maxsize = dev->drv[c->driver]->interface->maxbufsize; atomic_inc(&dev->v110use[idx]); switch (dev->v110emu[idx]) { case ISDN_PROTO_L2_V11096: dev->v110[idx] = isdn_v110_open(V110_9600, hdrlen, maxsize); break; case ISDN_PROTO_L2_V11019: dev->v110[idx] = isdn_v110_open(V110_19200, hdrlen, maxsize); break; case ISDN_PROTO_L2_V11038: dev->v110[idx] = isdn_v110_open(V110_38400, hdrlen, maxsize); break; default: } if ((v = dev->v110[idx])) { while (v->SyncInit) { struct sk_buff *skb = isdn_v110_sync(v); if (dev->drv[c->driver]->interface->writebuf_skb(c->driver, c->arg, 1, skb) <= 0) { dev_kfree_skb(skb); /* Unable to send, try later */ break; } v->SyncInit--; v->skbidle++; } } else printk(KERN_WARNING "isdn_v110: Couldn't open stream for chan %d\n", idx); atomic_dec(&dev->v110use[idx]); } break; default: return 0; } return 0; } |