1 /* $NetBSD: tftp.c,v 1.17 2003/06/11 01:44:32 briggs Exp $ */ 2 3 /* 4 * Copyright (c) 1983, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #ifndef lint 38 #if 0 39 static char sccsid[] = "@(#)tftp.c 8.1 (Berkeley) 6/6/93"; 40 #else 41 __RCSID("$NetBSD: tftp.c,v 1.17 2003/06/11 01:44:32 briggs Exp $"); 42 #endif 43 #endif /* not lint */ 44 45 /* Many bug fixes are from Jim Guyton <guyton@rand-unix> */ 46 47 /* 48 * TFTP User Program -- Protocol Machines 49 */ 50 #include <sys/types.h> 51 #include <sys/param.h> 52 #include <sys/socket.h> 53 #include <sys/stat.h> 54 #include <sys/time.h> 55 56 #include <netinet/in.h> 57 58 #include <arpa/tftp.h> 59 60 #include <err.h> 61 #include <errno.h> 62 #include <setjmp.h> 63 #include <signal.h> 64 #include <stdio.h> 65 #include <stdlib.h> 66 #include <string.h> 67 #include <unistd.h> 68 #include <netdb.h> 69 70 #include "extern.h" 71 #include "tftpsubs.h" 72 73 extern struct sockaddr_storage peeraddr; /* filled in by main */ 74 extern int f; /* the opened socket */ 75 extern int trace; 76 extern int verbose; 77 extern int def_rexmtval; 78 extern int rexmtval; 79 extern int maxtimeout; 80 extern int tsize; 81 extern int tout; 82 extern int def_blksize; 83 extern int blksize; 84 85 char ackbuf[PKTSIZE]; 86 int timeout; 87 jmp_buf toplevel; 88 jmp_buf timeoutbuf; 89 90 static void nak __P((int, struct sockaddr *)); 91 static int makerequest __P((int, const char *, struct tftphdr *, const char *, off_t)); 92 static void printstats __P((const char *, unsigned long)); 93 static void startclock __P((void)); 94 static void stopclock __P((void)); 95 static void timer __P((int)); 96 static void tpacket __P((const char *, struct tftphdr *, int)); 97 static int cmpport __P((struct sockaddr *, struct sockaddr *)); 98 99 static void get_options(struct tftphdr *, int); 100 101 static void 102 get_options(struct tftphdr *ap, int size) 103 { 104 unsigned long val; 105 char *opt, *endp, *nextopt, *valp; 106 int l; 107 108 size -= 2; /* skip over opcode */ 109 opt = ap->th_stuff; 110 endp = opt + size - 1; 111 *endp = '\0'; 112 113 while (opt < endp) { 114 l = strlen(opt) + 1; 115 valp = opt + l; 116 if (valp < endp) { 117 val = strtoul(valp, NULL, 10); 118 l = strlen(valp) + 1; 119 nextopt = valp + l; 120 if (val == ULONG_MAX && errno == ERANGE) { 121 /* Report illegal value */ 122 opt = nextopt; 123 continue; 124 } 125 } else { 126 /* Badly formed OACK */ 127 break; 128 } 129 if (strcmp(opt, "tsize") == 0) { 130 /* cool, but we'll ignore it */ 131 } else if (strcmp(opt, "timeout") == 0) { 132 if (val >= 1 && val <= 255) { 133 rexmtval = val; 134 } else { 135 /* Report error? */ 136 } 137 } else if (strcmp(opt, "blksize") == 0) { 138 if (val >= 8 && val <= MAXSEGSIZE) { 139 blksize = val; 140 } else { 141 /* Report error? */ 142 } 143 } else { 144 /* unknown option */ 145 } 146 opt = nextopt; 147 } 148 } 149 150 /* 151 * Send the requested file. 152 */ 153 void 154 sendfile(fd, name, mode) 155 int fd; 156 char *name; 157 char *mode; 158 { 159 struct tftphdr *ap; /* data and ack packets */ 160 struct tftphdr *dp; 161 int n; 162 volatile unsigned int block; 163 volatile int size, convert; 164 volatile unsigned long amount; 165 struct sockaddr_storage from; 166 struct stat sbuf; 167 off_t filesize=0; 168 int fromlen; 169 FILE *file; 170 struct sockaddr_storage peer; 171 struct sockaddr_storage serv; /* valid server port number */ 172 173 startclock(); /* start stat's clock */ 174 dp = r_init(); /* reset fillbuf/read-ahead code */ 175 ap = (struct tftphdr *)ackbuf; 176 if (tsize) { 177 if (fstat(fd, &sbuf) == 0) { 178 filesize = sbuf.st_size; 179 } else { 180 filesize = -1ULL; 181 } 182 } 183 file = fdopen(fd, "r"); 184 convert = !strcmp(mode, "netascii"); 185 block = 0; 186 amount = 0; 187 memcpy(&peer, &peeraddr, peeraddr.ss_len); 188 memset(&serv, 0, sizeof(serv)); 189 190 signal(SIGALRM, timer); 191 do { 192 if (block == 0) 193 size = makerequest(WRQ, name, dp, mode, filesize) - 4; 194 else { 195 /* size = read(fd, dp->th_data, SEGSIZE); */ 196 size = readit(file, &dp, blksize, convert); 197 if (size < 0) { 198 nak(errno + 100, (struct sockaddr *)&peer); 199 break; 200 } 201 dp->th_opcode = htons((u_short)DATA); 202 dp->th_block = htons((u_short)block); 203 } 204 timeout = 0; 205 (void) setjmp(timeoutbuf); 206 send_data: 207 if (trace) 208 tpacket("sent", dp, size + 4); 209 n = sendto(f, dp, size + 4, 0, 210 (struct sockaddr *)&peer, peer.ss_len); 211 if (n != size + 4) { 212 warn("sendto"); 213 goto abort; 214 } 215 if (block) 216 read_ahead(file, blksize, convert); 217 for ( ; ; ) { 218 alarm(rexmtval); 219 do { 220 fromlen = sizeof(from); 221 n = recvfrom(f, ackbuf, sizeof(ackbuf), 0, 222 (struct sockaddr *)&from, &fromlen); 223 } while (n <= 0); 224 alarm(0); 225 if (n < 0) { 226 warn("recvfrom"); 227 goto abort; 228 } 229 if (!serv.ss_family) 230 serv = from; 231 else if (!cmpport((struct sockaddr *)&serv, 232 (struct sockaddr *)&from)) { 233 warn("server port mismatch"); 234 goto abort; 235 } 236 peer = from; 237 if (trace) 238 tpacket("received", ap, n); 239 /* should verify packet came from server */ 240 ap->th_opcode = ntohs(ap->th_opcode); 241 ap->th_block = ntohs(ap->th_block); 242 if (ap->th_opcode == ERROR) { 243 printf("Error code %d: %s\n", ap->th_code, 244 ap->th_msg); 245 goto abort; 246 } 247 if (ap->th_opcode == ACK) { 248 int j; 249 250 if (ap->th_block == 0) { 251 /* 252 * If the extended options are enabled, 253 * the server just refused 'em all. 254 * The only one that _really_ 255 * matters is blksize, but we'll 256 * clear timeout, too. 257 */ 258 blksize = def_blksize; 259 rexmtval = def_rexmtval; 260 } 261 if (ap->th_block == block) { 262 break; 263 } 264 /* On an error, try to synchronize 265 * both sides. 266 */ 267 j = synchnet(f, blksize+4); 268 if (j && trace) { 269 printf("discarded %d packets\n", 270 j); 271 } 272 if (ap->th_block == (block-1)) { 273 goto send_data; 274 } 275 } 276 if (ap->th_opcode == OACK) { 277 if (block == 0) { 278 blksize = def_blksize; 279 rexmtval = def_rexmtval; 280 get_options(ap, n); 281 break; 282 } 283 } 284 } 285 if (block > 0) 286 amount += size; 287 block++; 288 } while (size == blksize || block == 1); 289 abort: 290 fclose(file); 291 stopclock(); 292 if (amount > 0) 293 printstats("Sent", amount); 294 } 295 296 /* 297 * Receive a file. 298 */ 299 void 300 recvfile(fd, name, mode) 301 int fd; 302 char *name; 303 char *mode; 304 { 305 struct tftphdr *ap; 306 struct tftphdr *dp; 307 int n, oack=0; 308 volatile unsigned int block; 309 volatile int size, firsttrip; 310 volatile unsigned long amount; 311 struct sockaddr_storage from; 312 int fromlen, readlen; 313 FILE *file; 314 volatile int convert; /* true if converting crlf -> lf */ 315 struct sockaddr_storage peer; 316 struct sockaddr_storage serv; /* valid server port number */ 317 318 startclock(); 319 dp = w_init(); 320 ap = (struct tftphdr *)ackbuf; 321 file = fdopen(fd, "w"); 322 convert = !strcmp(mode, "netascii"); 323 block = 1; 324 firsttrip = 1; 325 amount = 0; 326 memcpy(&peer, &peeraddr, peeraddr.ss_len); 327 memset(&serv, 0, sizeof(serv)); 328 329 signal(SIGALRM, timer); 330 do { 331 if (firsttrip) { 332 size = makerequest(RRQ, name, ap, mode, 0); 333 readlen = PKTSIZE; 334 firsttrip = 0; 335 } else { 336 ap->th_opcode = htons((u_short)ACK); 337 ap->th_block = htons((u_short)(block)); 338 readlen = blksize+4; 339 size = 4; 340 block++; 341 } 342 timeout = 0; 343 (void) setjmp(timeoutbuf); 344 send_ack: 345 if (trace) 346 tpacket("sent", ap, size); 347 if (sendto(f, ackbuf, size, 0, (struct sockaddr *)&peer, 348 peer.ss_len) != size) { 349 alarm(0); 350 warn("sendto"); 351 goto abort; 352 } 353 write_behind(file, convert); 354 for ( ; ; ) { 355 alarm(rexmtval); 356 do { 357 fromlen = sizeof(from); 358 n = recvfrom(f, dp, readlen, 0, 359 (struct sockaddr *)&from, &fromlen); 360 } while (n <= 0); 361 alarm(0); 362 if (n < 0) { 363 warn("recvfrom"); 364 goto abort; 365 } 366 if (!serv.ss_family) 367 serv = from; 368 else if (!cmpport((struct sockaddr *)&serv, 369 (struct sockaddr *)&from)) { 370 warn("server port mismatch"); 371 goto abort; 372 } 373 peer = from; 374 if (trace) 375 tpacket("received", dp, n); 376 /* should verify client address */ 377 dp->th_opcode = ntohs(dp->th_opcode); 378 dp->th_block = ntohs(dp->th_block); 379 if (dp->th_opcode == ERROR) { 380 printf("Error code %d: %s\n", dp->th_code, 381 dp->th_msg); 382 goto abort; 383 } 384 if (dp->th_opcode == DATA) { 385 int j; 386 387 if (dp->th_block == 1 && !oack) { 388 /* no OACK, revert to defaults */ 389 blksize = def_blksize; 390 rexmtval = def_rexmtval; 391 } 392 if (dp->th_block == block) { 393 break; /* have next packet */ 394 } 395 /* On an error, try to synchronize 396 * both sides. 397 */ 398 j = synchnet(f, blksize); 399 if (j && trace) { 400 printf("discarded %d packets\n", j); 401 } 402 if (dp->th_block == (block-1)) { 403 goto send_ack; /* resend ack */ 404 } 405 } 406 if (dp->th_opcode == OACK) { 407 if (block == 1) { 408 oack = 1; 409 blksize = def_blksize; 410 rexmtval = def_rexmtval; 411 get_options(dp, n); 412 ap->th_opcode = htons(ACK); 413 ap->th_block = 0; 414 readlen = blksize+4; 415 size = 4; 416 goto send_ack; 417 } 418 } 419 } 420 /* size = write(fd, dp->th_data, n - 4); */ 421 size = writeit(file, &dp, n - 4, convert); 422 if (size < 0) { 423 nak(errno + 100, (struct sockaddr *)&peer); 424 break; 425 } 426 amount += size; 427 } while (size == blksize || block == 1); 428 abort: /* ok to ack, since user */ 429 ap->th_opcode = htons((u_short)ACK); /* has seen err msg */ 430 ap->th_block = htons((u_short)block); 431 (void) sendto(f, ackbuf, 4, 0, (struct sockaddr *)&peer, 432 peer.ss_len); 433 write_behind(file, convert); /* flush last buffer */ 434 fclose(file); 435 stopclock(); 436 if (amount > 0) 437 printstats("Received", amount); 438 } 439 440 static int 441 makerequest(request, name, tp, mode, filesize) 442 int request; 443 const char *name; 444 struct tftphdr *tp; 445 const char *mode; 446 off_t filesize; 447 { 448 char *cp; 449 450 tp->th_opcode = htons((u_short)request); 451 #ifndef __SVR4 452 cp = tp->th_stuff; 453 #else 454 cp = (void *)&tp->th_stuff; 455 #endif 456 strcpy(cp, name); 457 cp += strlen(name); 458 *cp++ = '\0'; 459 strcpy(cp, mode); 460 cp += strlen(mode); 461 *cp++ = '\0'; 462 if (tsize) { 463 strcpy(cp, "tsize"); 464 cp += strlen(cp); 465 *cp++ = '\0'; 466 sprintf(cp, "%lu", (unsigned long) filesize); 467 cp += strlen(cp); 468 *cp++ = '\0'; 469 } 470 if (tout) { 471 strcpy(cp, "timeout"); 472 cp += strlen(cp); 473 *cp++ = '\0'; 474 sprintf(cp, "%d", rexmtval); 475 cp += strlen(cp); 476 *cp++ = '\0'; 477 } 478 if (blksize != SEGSIZE) { 479 strcpy(cp, "blksize"); 480 cp += strlen(cp); 481 *cp++ = '\0'; 482 sprintf(cp, "%d", blksize); 483 cp += strlen(cp); 484 *cp++ = '\0'; 485 } 486 return (cp - (char *)tp); 487 } 488 489 const struct errmsg { 490 int e_code; 491 const char *e_msg; 492 } errmsgs[] = { 493 { EUNDEF, "Undefined error code" }, 494 { ENOTFOUND, "File not found" }, 495 { EACCESS, "Access violation" }, 496 { ENOSPACE, "Disk full or allocation exceeded" }, 497 { EBADOP, "Illegal TFTP operation" }, 498 { EBADID, "Unknown transfer ID" }, 499 { EEXISTS, "File already exists" }, 500 { ENOUSER, "No such user" }, 501 { EOPTNEG, "Option negotiation failed" }, 502 { -1, 0 } 503 }; 504 505 /* 506 * Send a nak packet (error message). 507 * Error code passed in is one of the 508 * standard TFTP codes, or a UNIX errno 509 * offset by 100. 510 */ 511 static void 512 nak(error, peer) 513 int error; 514 struct sockaddr *peer; 515 { 516 const struct errmsg *pe; 517 struct tftphdr *tp; 518 int length; 519 size_t msglen; 520 521 tp = (struct tftphdr *)ackbuf; 522 tp->th_opcode = htons((u_short)ERROR); 523 msglen = sizeof(ackbuf) - (&tp->th_msg[0] - ackbuf); 524 for (pe = errmsgs; pe->e_code >= 0; pe++) 525 if (pe->e_code == error) 526 break; 527 if (pe->e_code < 0) { 528 tp->th_code = EUNDEF; 529 strlcpy(tp->th_msg, strerror(error - 100), msglen); 530 } else { 531 tp->th_code = htons((u_short)error); 532 strlcpy(tp->th_msg, pe->e_msg, msglen); 533 } 534 length = strlen(tp->th_msg); 535 msglen = &tp->th_msg[length + 1] - ackbuf; 536 if (trace) 537 tpacket("sent", tp, (int)msglen); 538 if (sendto(f, ackbuf, msglen, 0, peer, peer->sa_len) != msglen) 539 warn("nak"); 540 } 541 542 static void 543 tpacket(s, tp, n) 544 const char *s; 545 struct tftphdr *tp; 546 int n; 547 { 548 static char *opcodes[] = 549 { "#0", "RRQ", "WRQ", "DATA", "ACK", "ERROR", "OACK" }; 550 char *cp, *file, *endp, *opt, *spc; 551 u_short op = ntohs(tp->th_opcode); 552 int i, o; 553 554 if (op < RRQ || op > OACK) 555 printf("%s opcode=%x ", s, op); 556 else 557 printf("%s %s ", s, opcodes[op]); 558 switch (op) { 559 560 case RRQ: 561 case WRQ: 562 n -= 2; 563 #ifndef __SVR4 564 cp = tp->th_stuff; 565 #else 566 cp = (void *) &tp->th_stuff; 567 #endif 568 endp = cp + n - 1; 569 if (*endp != '\0') { /* Shouldn't happen, but... */ 570 *endp = '\0'; 571 } 572 file = cp; 573 cp = strchr(cp, '\0') + 1; 574 printf("<file=%s, mode=%s", file, cp); 575 cp = strchr(cp, '\0') + 1; 576 o = 0; 577 while (cp < endp) { 578 i = strlen(cp) + 1; 579 if (o) { 580 printf(", %s=%s", opt, cp); 581 } else { 582 opt = cp; 583 } 584 o = (o+1) % 2; 585 cp += i; 586 } 587 printf(">\n"); 588 break; 589 590 case DATA: 591 printf("<block=%d, %d bytes>\n", ntohs(tp->th_block), n - 4); 592 break; 593 594 case ACK: 595 printf("<block=%d>\n", ntohs(tp->th_block)); 596 break; 597 598 case ERROR: 599 printf("<code=%d, msg=%s>\n", ntohs(tp->th_code), tp->th_msg); 600 break; 601 602 case OACK: 603 o = 0; 604 n -= 2; 605 cp = tp->th_stuff; 606 endp = cp + n - 1; 607 if (*endp != '\0') { /* Shouldn't happen, but... */ 608 *endp = '\0'; 609 } 610 printf("<"); 611 spc = ""; 612 while (cp < endp) { 613 i = strlen(cp) + 1; 614 if (o) { 615 printf("%s%s=%s", spc, opt, cp); 616 spc = ", "; 617 } else { 618 opt = cp; 619 } 620 o = (o+1) % 2; 621 cp += i; 622 } 623 printf(">\n"); 624 break; 625 } 626 } 627 628 struct timeval tstart; 629 struct timeval tstop; 630 631 static void 632 startclock() 633 { 634 635 (void)gettimeofday(&tstart, NULL); 636 } 637 638 static void 639 stopclock() 640 { 641 642 (void)gettimeofday(&tstop, NULL); 643 } 644 645 static void 646 printstats(direction, amount) 647 const char *direction; 648 unsigned long amount; 649 { 650 double delta; 651 652 /* compute delta in 1/10's second units */ 653 delta = ((tstop.tv_sec*10.)+(tstop.tv_usec/100000)) - 654 ((tstart.tv_sec*10.)+(tstart.tv_usec/100000)); 655 delta = delta/10.; /* back to seconds */ 656 printf("%s %ld bytes in %.1f seconds", direction, amount, delta); 657 if (verbose) 658 printf(" [%.0f bits/sec]", (amount*8.)/delta); 659 putchar('\n'); 660 } 661 662 static void 663 timer(sig) 664 int sig; 665 { 666 667 timeout += rexmtval; 668 if (timeout >= maxtimeout) { 669 printf("Transfer timed out.\n"); 670 longjmp(toplevel, -1); 671 } 672 longjmp(timeoutbuf, 1); 673 } 674 675 static int 676 cmpport(sa, sb) 677 struct sockaddr *sa; 678 struct sockaddr *sb; 679 { 680 char a[NI_MAXSERV], b[NI_MAXSERV]; 681 682 if (getnameinfo(sa, sa->sa_len, NULL, 0, a, sizeof(a), NI_NUMERICSERV)) 683 return 0; 684 if (getnameinfo(sb, sb->sa_len, NULL, 0, b, sizeof(b), NI_NUMERICSERV)) 685 return 0; 686 if (strcmp(a, b) != 0) 687 return 0; 688 689 return 1; 690 } 691