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