1 /* 2 * This program is free software; you can redistribute it and/or modify 3 * it under the terms of the GNU General Public License as published by 4 * the Free Software Foundation; either version 2 of the License, or 5 * (at your option) any later version. 6 * 7 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) 8 */ 9 #include <linux/errno.h> 10 #include <linux/types.h> 11 #include <linux/socket.h> 12 #include <linux/in.h> 13 #include <linux/kernel.h> 14 #include <linux/timer.h> 15 #include <linux/string.h> 16 #include <linux/sockios.h> 17 #include <linux/net.h> 18 #include <linux/slab.h> 19 #include <net/ax25.h> 20 #include <linux/inet.h> 21 #include <linux/netdevice.h> 22 #include <linux/skbuff.h> 23 #include <net/sock.h> 24 #include <net/tcp_states.h> 25 #include <linux/fcntl.h> 26 #include <linux/mm.h> 27 #include <linux/interrupt.h> 28 #include <net/rose.h> 29 30 static int rose_create_facilities(unsigned char *buffer, struct rose_sock *rose); 31 32 /* 33 * This routine purges all of the queues of frames. 34 */ 35 void rose_clear_queues(struct sock *sk) 36 { 37 skb_queue_purge(&sk->sk_write_queue); 38 skb_queue_purge(&rose_sk(sk)->ack_queue); 39 } 40 41 /* 42 * This routine purges the input queue of those frames that have been 43 * acknowledged. This replaces the boxes labelled "V(a) <- N(r)" on the 44 * SDL diagram. 45 */ 46 void rose_frames_acked(struct sock *sk, unsigned short nr) 47 { 48 struct sk_buff *skb; 49 struct rose_sock *rose = rose_sk(sk); 50 51 /* 52 * Remove all the ack-ed frames from the ack queue. 53 */ 54 if (rose->va != nr) { 55 while (skb_peek(&rose->ack_queue) != NULL && rose->va != nr) { 56 skb = skb_dequeue(&rose->ack_queue); 57 kfree_skb(skb); 58 rose->va = (rose->va + 1) % ROSE_MODULUS; 59 } 60 } 61 } 62 63 void rose_requeue_frames(struct sock *sk) 64 { 65 struct sk_buff *skb, *skb_prev = NULL; 66 67 /* 68 * Requeue all the un-ack-ed frames on the output queue to be picked 69 * up by rose_kick. This arrangement handles the possibility of an 70 * empty output queue. 71 */ 72 while ((skb = skb_dequeue(&rose_sk(sk)->ack_queue)) != NULL) { 73 if (skb_prev == NULL) 74 skb_queue_head(&sk->sk_write_queue, skb); 75 else 76 skb_append(skb_prev, skb, &sk->sk_write_queue); 77 skb_prev = skb; 78 } 79 } 80 81 /* 82 * Validate that the value of nr is between va and vs. Return true or 83 * false for testing. 84 */ 85 int rose_validate_nr(struct sock *sk, unsigned short nr) 86 { 87 struct rose_sock *rose = rose_sk(sk); 88 unsigned short vc = rose->va; 89 90 while (vc != rose->vs) { 91 if (nr == vc) return 1; 92 vc = (vc + 1) % ROSE_MODULUS; 93 } 94 95 return nr == rose->vs; 96 } 97 98 /* 99 * This routine is called when the packet layer internally generates a 100 * control frame. 101 */ 102 void rose_write_internal(struct sock *sk, int frametype) 103 { 104 struct rose_sock *rose = rose_sk(sk); 105 struct sk_buff *skb; 106 unsigned char *dptr; 107 unsigned char lci1, lci2; 108 int maxfaclen = 0; 109 int len, faclen; 110 int reserve; 111 112 reserve = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + 1; 113 len = ROSE_MIN_LEN; 114 115 switch (frametype) { 116 case ROSE_CALL_REQUEST: 117 len += 1 + ROSE_ADDR_LEN + ROSE_ADDR_LEN; 118 maxfaclen = 256; 119 break; 120 case ROSE_CALL_ACCEPTED: 121 case ROSE_CLEAR_REQUEST: 122 case ROSE_RESET_REQUEST: 123 len += 2; 124 break; 125 } 126 127 skb = alloc_skb(reserve + len + maxfaclen, GFP_ATOMIC); 128 if (!skb) 129 return; 130 131 /* 132 * Space for AX.25 header and PID. 133 */ 134 skb_reserve(skb, reserve); 135 136 dptr = skb_put(skb, len); 137 138 lci1 = (rose->lci >> 8) & 0x0F; 139 lci2 = (rose->lci >> 0) & 0xFF; 140 141 switch (frametype) { 142 case ROSE_CALL_REQUEST: 143 *dptr++ = ROSE_GFI | lci1; 144 *dptr++ = lci2; 145 *dptr++ = frametype; 146 *dptr++ = ROSE_CALL_REQ_ADDR_LEN_VAL; 147 memcpy(dptr, &rose->dest_addr, ROSE_ADDR_LEN); 148 dptr += ROSE_ADDR_LEN; 149 memcpy(dptr, &rose->source_addr, ROSE_ADDR_LEN); 150 dptr += ROSE_ADDR_LEN; 151 faclen = rose_create_facilities(dptr, rose); 152 skb_put(skb, faclen); 153 dptr += faclen; 154 break; 155 156 case ROSE_CALL_ACCEPTED: 157 *dptr++ = ROSE_GFI | lci1; 158 *dptr++ = lci2; 159 *dptr++ = frametype; 160 *dptr++ = 0x00; /* Address length */ 161 *dptr++ = 0; /* Facilities length */ 162 break; 163 164 case ROSE_CLEAR_REQUEST: 165 *dptr++ = ROSE_GFI | lci1; 166 *dptr++ = lci2; 167 *dptr++ = frametype; 168 *dptr++ = rose->cause; 169 *dptr++ = rose->diagnostic; 170 break; 171 172 case ROSE_RESET_REQUEST: 173 *dptr++ = ROSE_GFI | lci1; 174 *dptr++ = lci2; 175 *dptr++ = frametype; 176 *dptr++ = ROSE_DTE_ORIGINATED; 177 *dptr++ = 0; 178 break; 179 180 case ROSE_RR: 181 case ROSE_RNR: 182 *dptr++ = ROSE_GFI | lci1; 183 *dptr++ = lci2; 184 *dptr = frametype; 185 *dptr++ |= (rose->vr << 5) & 0xE0; 186 break; 187 188 case ROSE_CLEAR_CONFIRMATION: 189 case ROSE_RESET_CONFIRMATION: 190 *dptr++ = ROSE_GFI | lci1; 191 *dptr++ = lci2; 192 *dptr++ = frametype; 193 break; 194 195 default: 196 printk(KERN_ERR "ROSE: rose_write_internal - invalid frametype %02X\n", frametype); 197 kfree_skb(skb); 198 return; 199 } 200 201 rose_transmit_link(skb, rose->neighbour); 202 } 203 204 int rose_decode(struct sk_buff *skb, int *ns, int *nr, int *q, int *d, int *m) 205 { 206 unsigned char *frame; 207 208 frame = skb->data; 209 210 *ns = *nr = *q = *d = *m = 0; 211 212 switch (frame[2]) { 213 case ROSE_CALL_REQUEST: 214 case ROSE_CALL_ACCEPTED: 215 case ROSE_CLEAR_REQUEST: 216 case ROSE_CLEAR_CONFIRMATION: 217 case ROSE_RESET_REQUEST: 218 case ROSE_RESET_CONFIRMATION: 219 return frame[2]; 220 default: 221 break; 222 } 223 224 if ((frame[2] & 0x1F) == ROSE_RR || 225 (frame[2] & 0x1F) == ROSE_RNR) { 226 *nr = (frame[2] >> 5) & 0x07; 227 return frame[2] & 0x1F; 228 } 229 230 if ((frame[2] & 0x01) == ROSE_DATA) { 231 *q = (frame[0] & ROSE_Q_BIT) == ROSE_Q_BIT; 232 *d = (frame[0] & ROSE_D_BIT) == ROSE_D_BIT; 233 *m = (frame[2] & ROSE_M_BIT) == ROSE_M_BIT; 234 *nr = (frame[2] >> 5) & 0x07; 235 *ns = (frame[2] >> 1) & 0x07; 236 return ROSE_DATA; 237 } 238 239 return ROSE_ILLEGAL; 240 } 241 242 static int rose_parse_national(unsigned char *p, struct rose_facilities_struct *facilities, int len) 243 { 244 unsigned char *pt; 245 unsigned char l, lg, n = 0; 246 int fac_national_digis_received = 0; 247 248 do { 249 switch (*p & 0xC0) { 250 case 0x00: 251 if (len < 2) 252 return -1; 253 p += 2; 254 n += 2; 255 len -= 2; 256 break; 257 258 case 0x40: 259 if (len < 3) 260 return -1; 261 if (*p == FAC_NATIONAL_RAND) 262 facilities->rand = ((p[1] << 8) & 0xFF00) + ((p[2] << 0) & 0x00FF); 263 p += 3; 264 n += 3; 265 len -= 3; 266 break; 267 268 case 0x80: 269 if (len < 4) 270 return -1; 271 p += 4; 272 n += 4; 273 len -= 4; 274 break; 275 276 case 0xC0: 277 if (len < 2) 278 return -1; 279 l = p[1]; 280 if (len < 2 + l) 281 return -1; 282 if (*p == FAC_NATIONAL_DEST_DIGI) { 283 if (!fac_national_digis_received) { 284 if (l < AX25_ADDR_LEN) 285 return -1; 286 memcpy(&facilities->source_digis[0], p + 2, AX25_ADDR_LEN); 287 facilities->source_ndigis = 1; 288 } 289 } 290 else if (*p == FAC_NATIONAL_SRC_DIGI) { 291 if (!fac_national_digis_received) { 292 if (l < AX25_ADDR_LEN) 293 return -1; 294 memcpy(&facilities->dest_digis[0], p + 2, AX25_ADDR_LEN); 295 facilities->dest_ndigis = 1; 296 } 297 } 298 else if (*p == FAC_NATIONAL_FAIL_CALL) { 299 if (l < AX25_ADDR_LEN) 300 return -1; 301 memcpy(&facilities->fail_call, p + 2, AX25_ADDR_LEN); 302 } 303 else if (*p == FAC_NATIONAL_FAIL_ADD) { 304 if (l < 1 + ROSE_ADDR_LEN) 305 return -1; 306 memcpy(&facilities->fail_addr, p + 3, ROSE_ADDR_LEN); 307 } 308 else if (*p == FAC_NATIONAL_DIGIS) { 309 if (l % AX25_ADDR_LEN) 310 return -1; 311 fac_national_digis_received = 1; 312 facilities->source_ndigis = 0; 313 facilities->dest_ndigis = 0; 314 for (pt = p + 2, lg = 0 ; lg < l ; pt += AX25_ADDR_LEN, lg += AX25_ADDR_LEN) { 315 if (pt[6] & AX25_HBIT) { 316 if (facilities->dest_ndigis >= ROSE_MAX_DIGIS) 317 return -1; 318 memcpy(&facilities->dest_digis[facilities->dest_ndigis++], pt, AX25_ADDR_LEN); 319 } else { 320 if (facilities->source_ndigis >= ROSE_MAX_DIGIS) 321 return -1; 322 memcpy(&facilities->source_digis[facilities->source_ndigis++], pt, AX25_ADDR_LEN); 323 } 324 } 325 } 326 p += l + 2; 327 n += l + 2; 328 len -= l + 2; 329 break; 330 } 331 } while (*p != 0x00 && len > 0); 332 333 return n; 334 } 335 336 static int rose_parse_ccitt(unsigned char *p, struct rose_facilities_struct *facilities, int len) 337 { 338 unsigned char l, n = 0; 339 char callsign[11]; 340 341 do { 342 switch (*p & 0xC0) { 343 case 0x00: 344 if (len < 2) 345 return -1; 346 p += 2; 347 n += 2; 348 len -= 2; 349 break; 350 351 case 0x40: 352 if (len < 3) 353 return -1; 354 p += 3; 355 n += 3; 356 len -= 3; 357 break; 358 359 case 0x80: 360 if (len < 4) 361 return -1; 362 p += 4; 363 n += 4; 364 len -= 4; 365 break; 366 367 case 0xC0: 368 if (len < 2) 369 return -1; 370 l = p[1]; 371 372 /* Prevent overflows*/ 373 if (l < 10 || l > 20) 374 return -1; 375 376 if (*p == FAC_CCITT_DEST_NSAP) { 377 memcpy(&facilities->source_addr, p + 7, ROSE_ADDR_LEN); 378 memcpy(callsign, p + 12, l - 10); 379 callsign[l - 10] = '\0'; 380 asc2ax(&facilities->source_call, callsign); 381 } 382 if (*p == FAC_CCITT_SRC_NSAP) { 383 memcpy(&facilities->dest_addr, p + 7, ROSE_ADDR_LEN); 384 memcpy(callsign, p + 12, l - 10); 385 callsign[l - 10] = '\0'; 386 asc2ax(&facilities->dest_call, callsign); 387 } 388 p += l + 2; 389 n += l + 2; 390 len -= l + 2; 391 break; 392 } 393 } while (*p != 0x00 && len > 0); 394 395 return n; 396 } 397 398 int rose_parse_facilities(unsigned char *p, unsigned packet_len, 399 struct rose_facilities_struct *facilities) 400 { 401 int facilities_len, len; 402 403 facilities_len = *p++; 404 405 if (facilities_len == 0 || (unsigned int)facilities_len > packet_len) 406 return 0; 407 408 while (facilities_len >= 3 && *p == 0x00) { 409 facilities_len--; 410 p++; 411 412 switch (*p) { 413 case FAC_NATIONAL: /* National */ 414 len = rose_parse_national(p + 1, facilities, facilities_len - 1); 415 break; 416 417 case FAC_CCITT: /* CCITT */ 418 len = rose_parse_ccitt(p + 1, facilities, facilities_len - 1); 419 break; 420 421 default: 422 printk(KERN_DEBUG "ROSE: rose_parse_facilities - unknown facilities family %02X\n", *p); 423 len = 1; 424 break; 425 } 426 427 if (len < 0) 428 return 0; 429 if (WARN_ON(len >= facilities_len)) 430 return 0; 431 facilities_len -= len + 1; 432 p += len + 1; 433 } 434 435 return facilities_len == 0; 436 } 437 438 static int rose_create_facilities(unsigned char *buffer, struct rose_sock *rose) 439 { 440 unsigned char *p = buffer + 1; 441 char *callsign; 442 char buf[11]; 443 int len, nb; 444 445 /* National Facilities */ 446 if (rose->rand != 0 || rose->source_ndigis == 1 || rose->dest_ndigis == 1) { 447 *p++ = 0x00; 448 *p++ = FAC_NATIONAL; 449 450 if (rose->rand != 0) { 451 *p++ = FAC_NATIONAL_RAND; 452 *p++ = (rose->rand >> 8) & 0xFF; 453 *p++ = (rose->rand >> 0) & 0xFF; 454 } 455 456 /* Sent before older facilities */ 457 if ((rose->source_ndigis > 0) || (rose->dest_ndigis > 0)) { 458 int maxdigi = 0; 459 *p++ = FAC_NATIONAL_DIGIS; 460 *p++ = AX25_ADDR_LEN * (rose->source_ndigis + rose->dest_ndigis); 461 for (nb = 0 ; nb < rose->source_ndigis ; nb++) { 462 if (++maxdigi >= ROSE_MAX_DIGIS) 463 break; 464 memcpy(p, &rose->source_digis[nb], AX25_ADDR_LEN); 465 p[6] |= AX25_HBIT; 466 p += AX25_ADDR_LEN; 467 } 468 for (nb = 0 ; nb < rose->dest_ndigis ; nb++) { 469 if (++maxdigi >= ROSE_MAX_DIGIS) 470 break; 471 memcpy(p, &rose->dest_digis[nb], AX25_ADDR_LEN); 472 p[6] &= ~AX25_HBIT; 473 p += AX25_ADDR_LEN; 474 } 475 } 476 477 /* For compatibility */ 478 if (rose->source_ndigis > 0) { 479 *p++ = FAC_NATIONAL_SRC_DIGI; 480 *p++ = AX25_ADDR_LEN; 481 memcpy(p, &rose->source_digis[0], AX25_ADDR_LEN); 482 p += AX25_ADDR_LEN; 483 } 484 485 /* For compatibility */ 486 if (rose->dest_ndigis > 0) { 487 *p++ = FAC_NATIONAL_DEST_DIGI; 488 *p++ = AX25_ADDR_LEN; 489 memcpy(p, &rose->dest_digis[0], AX25_ADDR_LEN); 490 p += AX25_ADDR_LEN; 491 } 492 } 493 494 *p++ = 0x00; 495 *p++ = FAC_CCITT; 496 497 *p++ = FAC_CCITT_DEST_NSAP; 498 499 callsign = ax2asc(buf, &rose->dest_call); 500 501 *p++ = strlen(callsign) + 10; 502 *p++ = (strlen(callsign) + 9) * 2; /* ??? */ 503 504 *p++ = 0x47; *p++ = 0x00; *p++ = 0x11; 505 *p++ = ROSE_ADDR_LEN * 2; 506 memcpy(p, &rose->dest_addr, ROSE_ADDR_LEN); 507 p += ROSE_ADDR_LEN; 508 509 memcpy(p, callsign, strlen(callsign)); 510 p += strlen(callsign); 511 512 *p++ = FAC_CCITT_SRC_NSAP; 513 514 callsign = ax2asc(buf, &rose->source_call); 515 516 *p++ = strlen(callsign) + 10; 517 *p++ = (strlen(callsign) + 9) * 2; /* ??? */ 518 519 *p++ = 0x47; *p++ = 0x00; *p++ = 0x11; 520 *p++ = ROSE_ADDR_LEN * 2; 521 memcpy(p, &rose->source_addr, ROSE_ADDR_LEN); 522 p += ROSE_ADDR_LEN; 523 524 memcpy(p, callsign, strlen(callsign)); 525 p += strlen(callsign); 526 527 len = p - buffer; 528 buffer[0] = len - 1; 529 530 return len; 531 } 532 533 void rose_disconnect(struct sock *sk, int reason, int cause, int diagnostic) 534 { 535 struct rose_sock *rose = rose_sk(sk); 536 537 rose_stop_timer(sk); 538 rose_stop_idletimer(sk); 539 540 rose_clear_queues(sk); 541 542 rose->lci = 0; 543 rose->state = ROSE_STATE_0; 544 545 if (cause != -1) 546 rose->cause = cause; 547 548 if (diagnostic != -1) 549 rose->diagnostic = diagnostic; 550 551 sk->sk_state = TCP_CLOSE; 552 sk->sk_err = reason; 553 sk->sk_shutdown |= SEND_SHUTDOWN; 554 555 if (!sock_flag(sk, SOCK_DEAD)) { 556 sk->sk_state_change(sk); 557 sock_set_flag(sk, SOCK_DEAD); 558 } 559 } 560