1 /* $NetBSD: ftp.c,v 1.6 2013/10/19 22:58:40 mrg Exp $ */ 2 /*- 3 * Copyright (c) 1998-2004 Dag-Erling Co�dan Sm�rgrav 4 * Copyright (c) 2008, 2009, 2010 Joerg Sonnenberger <joerg@NetBSD.org> 5 * 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 * in this position and unchanged. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. The name of the author may not be used to endorse or promote products 17 * derived from this software without specific prior written permission 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 * 30 * $FreeBSD: ftp.c,v 1.101 2008/01/23 20:57:59 des Exp $ 31 */ 32 33 /* 34 * Portions of this code were taken from or based on ftpio.c: 35 * 36 * ---------------------------------------------------------------------------- 37 * "THE BEER-WARE LICENSE" (Revision 42): 38 * <phk@FreeBSD.org> wrote this file. As long as you retain this notice you 39 * can do whatever you want with this stuff. If we meet some day, and you think 40 * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp 41 * ---------------------------------------------------------------------------- 42 * 43 * Major Changelog: 44 * 45 * Dag-Erling Co�dan Sm�rgrav 46 * 9 Jun 1998 47 * 48 * Incorporated into libfetch 49 * 50 * Jordan K. Hubbard 51 * 17 Jan 1996 52 * 53 * Turned inside out. Now returns xfers as new file ids, not as a special 54 * `state' of FTP_t 55 * 56 * $ftpioId: ftpio.c,v 1.30 1998/04/11 07:28:53 phk Exp $ 57 * 58 */ 59 60 #ifdef __linux__ 61 /* Keep this down to Linux, it can create surprises else where. */ 62 #define _GNU_SOURCE 63 #endif 64 65 #if HAVE_CONFIG_H 66 #include "config.h" 67 #endif 68 #ifndef NETBSD 69 #include <nbcompat.h> 70 #endif 71 72 #include <sys/types.h> 73 #include <sys/socket.h> 74 75 #include <netinet/in.h> 76 #include <arpa/inet.h> 77 78 #include <ctype.h> 79 #include <errno.h> 80 #include <fcntl.h> 81 #if defined(HAVE_INTTYPES_H) || defined(NETBSD) 82 #include <inttypes.h> 83 #endif 84 #include <stdarg.h> 85 #ifndef NETBSD 86 #include <nbcompat/netdb.h> 87 #include <nbcompat/stdio.h> 88 #else 89 #include <netdb.h> 90 #include <stdio.h> 91 #endif 92 #include <stdlib.h> 93 #include <string.h> 94 #include <time.h> 95 #include <unistd.h> 96 97 #include "fetch.h" 98 #include "common.h" 99 #include "ftperr.h" 100 101 #define FTP_ANONYMOUS_USER "anonymous" 102 103 #define FTP_CONNECTION_ALREADY_OPEN 125 104 #define FTP_OPEN_DATA_CONNECTION 150 105 #define FTP_OK 200 106 #define FTP_FILE_STATUS 213 107 #define FTP_SERVICE_READY 220 108 #define FTP_TRANSFER_COMPLETE 226 109 #define FTP_PASSIVE_MODE 227 110 #define FTP_LPASSIVE_MODE 228 111 #define FTP_EPASSIVE_MODE 229 112 #define FTP_LOGGED_IN 230 113 #define FTP_FILE_ACTION_OK 250 114 #define FTP_DIRECTORY_CREATED 257 /* multiple meanings */ 115 #define FTP_FILE_CREATED 257 /* multiple meanings */ 116 #define FTP_WORKING_DIRECTORY 257 /* multiple meanings */ 117 #define FTP_NEED_PASSWORD 331 118 #define FTP_NEED_ACCOUNT 332 119 #define FTP_FILE_OK 350 120 #define FTP_SYNTAX_ERROR 500 121 #define FTP_PROTOCOL_ERROR 999 122 123 #define isftpreply(foo) \ 124 (isdigit((unsigned char)foo[0]) && \ 125 isdigit((unsigned char)foo[1]) && \ 126 isdigit((unsigned char)foo[2]) && \ 127 (foo[3] == ' ' || foo[3] == '\0')) 128 #define isftpinfo(foo) \ 129 (isdigit((unsigned char)foo[0]) && \ 130 isdigit((unsigned char)foo[1]) && \ 131 isdigit((unsigned char)foo[2]) && \ 132 foo[3] == '-') 133 134 /* 135 * Translate IPv4 mapped IPv6 address to IPv4 address 136 */ 137 static void 138 unmappedaddr(struct sockaddr_in6 *sin6, socklen_t *len) 139 { 140 struct sockaddr_in *sin4; 141 void *addrp; 142 uint32_t addr; 143 int port; 144 145 if (sin6->sin6_family != AF_INET6 || 146 !IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) 147 return; 148 sin4 = (struct sockaddr_in *)(void *)sin6; 149 addrp = &sin6->sin6_addr.s6_addr[12]; 150 addr = *(uint32_t *)addrp; 151 port = sin6->sin6_port; 152 memset(sin4, 0, sizeof(struct sockaddr_in)); 153 sin4->sin_addr.s_addr = addr; 154 sin4->sin_port = port; 155 sin4->sin_family = AF_INET; 156 *len = sizeof(struct sockaddr_in); 157 #ifdef HAVE_SA_LEN 158 sin4->sin_len = sizeof(struct sockaddr_in); 159 #endif 160 } 161 162 /* 163 * Get server response 164 */ 165 static int 166 ftp_chkerr(conn_t *conn) 167 { 168 if (fetch_getln(conn) == -1) { 169 fetch_syserr(); 170 return (-1); 171 } 172 if (isftpinfo(conn->buf)) { 173 while (conn->buflen && !isftpreply(conn->buf)) { 174 if (fetch_getln(conn) == -1) { 175 fetch_syserr(); 176 return (-1); 177 } 178 } 179 } 180 181 while (conn->buflen && 182 isspace((unsigned char)conn->buf[conn->buflen - 1])) 183 conn->buflen--; 184 conn->buf[conn->buflen] = '\0'; 185 186 if (!isftpreply(conn->buf)) { 187 ftp_seterr(FTP_PROTOCOL_ERROR); 188 return (-1); 189 } 190 191 conn->err = (conn->buf[0] - '0') * 100 192 + (conn->buf[1] - '0') * 10 193 + (conn->buf[2] - '0'); 194 195 return (conn->err); 196 } 197 198 /* 199 * Send a command and check reply 200 */ 201 static int 202 ftp_cmd(conn_t *conn, const char *fmt, ...) 203 { 204 va_list ap; 205 size_t len; 206 char *msg; 207 ssize_t r; 208 209 va_start(ap, fmt); 210 len = vasprintf(&msg, fmt, ap); 211 va_end(ap); 212 213 if (msg == NULL) { 214 errno = ENOMEM; 215 fetch_syserr(); 216 return (-1); 217 } 218 219 r = fetch_write(conn, msg, len); 220 free(msg); 221 222 if (r == -1) { 223 fetch_syserr(); 224 return (-1); 225 } 226 227 return (ftp_chkerr(conn)); 228 } 229 230 /* 231 * Return a pointer to the filename part of a path 232 */ 233 static const char * 234 ftp_filename(const char *file, size_t *len, int *type, int subdir) 235 { 236 const char *s; 237 238 if ((s = strrchr(file, '/')) == NULL || subdir) 239 s = file; 240 else 241 s = s + 1; 242 *len = strlen(s); 243 if (*len > 7 && strncmp(s + *len - 7, ";type=", 6) == 0) { 244 *type = s[*len - 1]; 245 *len -= 7; 246 } else { 247 *type = '\0'; 248 } 249 return (s); 250 } 251 252 /* 253 * Get current working directory from the reply to a CWD, PWD or CDUP 254 * command. 255 */ 256 static int 257 ftp_pwd(conn_t *conn, char **pwd) 258 { 259 char *src, *dst, *end; 260 int q; 261 size_t len; 262 263 if (conn->err != FTP_WORKING_DIRECTORY && 264 conn->err != FTP_FILE_ACTION_OK) 265 return (FTP_PROTOCOL_ERROR); 266 end = conn->buf + conn->buflen; 267 src = conn->buf + 4; 268 if (src >= end || *src++ != '"') 269 return (FTP_PROTOCOL_ERROR); 270 len = end - src + 1; 271 *pwd = malloc(len); 272 if (*pwd == NULL) 273 return (FTP_PROTOCOL_ERROR); 274 for (q = 0, dst = *pwd; src < end; ++src) { 275 if (!q && *src == '"') 276 q = 1; 277 else if (q && *src != '"') 278 break; 279 else if (q) 280 *dst++ = '"', q = 0; 281 else 282 *dst++ = *src; 283 } 284 *dst = '\0'; 285 if (**pwd != '/') { 286 free(*pwd); 287 *pwd = NULL; 288 return (FTP_PROTOCOL_ERROR); 289 } 290 return (FTP_OK); 291 } 292 293 /* 294 * Change working directory to the directory that contains the specified 295 * file. 296 */ 297 static int 298 ftp_cwd(conn_t *conn, const char *path, int subdir) 299 { 300 const char *beg, *end; 301 char *pwd, *dst; 302 int e; 303 size_t i, len; 304 305 if (*path != '/') { 306 ftp_seterr(501); 307 return (-1); 308 } 309 ++path; 310 311 /* Simple case: still in the home directory and no directory change. */ 312 if (conn->ftp_home == NULL && strchr(path, '/') == NULL && 313 (!subdir || *path == '\0')) 314 return 0; 315 316 if ((e = ftp_cmd(conn, "PWD\r\n")) != FTP_WORKING_DIRECTORY || 317 (e = ftp_pwd(conn, &pwd)) != FTP_OK) { 318 ftp_seterr(e); 319 return (-1); 320 } 321 if (conn->ftp_home == NULL && (conn->ftp_home = strdup(pwd)) == NULL) { 322 fetch_syserr(); 323 free(pwd); 324 return (-1); 325 } 326 if (*path == '/') { 327 while (path[1] == '/') 328 ++path; 329 dst = strdup(path); 330 } else if (strcmp(conn->ftp_home, "/") == 0) { 331 dst = strdup(path - 1); 332 } else { 333 asprintf(&dst, "%s/%s", conn->ftp_home, path); 334 } 335 if (dst == NULL) { 336 fetch_syserr(); 337 free(pwd); 338 return (-1); 339 } 340 341 if (subdir) 342 end = dst + strlen(dst); 343 else 344 end = strrchr(dst, '/'); 345 346 for (;;) { 347 len = strlen(pwd); 348 349 /* Look for a common prefix between PWD and dir to fetch. */ 350 for (i = 0; i <= len && i <= (size_t)(end - dst); ++i) 351 if (pwd[i] != dst[i]) 352 break; 353 /* Keep going up a dir until we have a matching prefix. */ 354 if (strcmp(pwd, "/") == 0) 355 break; 356 if (pwd[i] == '\0' && (dst[i - 1] == '/' || dst[i] == '/')) 357 break; 358 free(pwd); 359 if ((e = ftp_cmd(conn, "CDUP\r\n")) != FTP_FILE_ACTION_OK || 360 (e = ftp_cmd(conn, "PWD\r\n")) != FTP_WORKING_DIRECTORY || 361 (e = ftp_pwd(conn, &pwd)) != FTP_OK) { 362 ftp_seterr(e); 363 free(dst); 364 return (-1); 365 } 366 } 367 free(pwd); 368 369 #ifdef FTP_COMBINE_CWDS 370 /* Skip leading slashes, even "////". */ 371 for (beg = dst + i; beg < end && *beg == '/'; ++beg, ++i) 372 /* nothing */ ; 373 374 /* If there is no trailing dir, we're already there. */ 375 if (beg >= end) { 376 free(dst); 377 return (0); 378 } 379 380 /* Change to the directory all in one chunk (e.g., foo/bar/baz). */ 381 e = ftp_cmd(conn, "CWD %.*s\r\n", (int)(end - beg), beg); 382 if (e == FTP_FILE_ACTION_OK) { 383 free(dst); 384 return (0); 385 } 386 #endif /* FTP_COMBINE_CWDS */ 387 388 /* That didn't work so go back to legacy behavior (multiple CWDs). */ 389 for (beg = dst + i; beg < end; beg = dst + i + 1) { 390 while (*beg == '/') 391 ++beg, ++i; 392 for (++i; dst + i < end && dst[i] != '/'; ++i) 393 /* nothing */ ; 394 e = ftp_cmd(conn, "CWD %.*s\r\n", dst + i - beg, beg); 395 if (e != FTP_FILE_ACTION_OK) { 396 free(dst); 397 ftp_seterr(e); 398 return (-1); 399 } 400 } 401 free(dst); 402 return (0); 403 } 404 405 /* 406 * Set transfer mode and data type 407 */ 408 static int 409 ftp_mode_type(conn_t *conn, int mode, int type) 410 { 411 int e; 412 413 switch (mode) { 414 case 0: 415 case 's': 416 mode = 'S'; 417 /*FALLTHROUGH*/ 418 case 'S': 419 break; 420 default: 421 return (FTP_PROTOCOL_ERROR); 422 } 423 if ((e = ftp_cmd(conn, "MODE %c\r\n", mode)) != FTP_OK) { 424 if (mode == 'S') { 425 /* 426 * Stream mode is supposed to be the default - so 427 * much so that some servers not only do not 428 * support any other mode, but do not support the 429 * MODE command at all. 430 * 431 * If "MODE S" fails, it is unlikely that we 432 * previously succeeded in setting a different 433 * mode. Therefore, we simply hope that the 434 * server is already in the correct mode, and 435 * silently ignore the failure. 436 */ 437 } else { 438 return (e); 439 } 440 } 441 442 switch (type) { 443 case 0: 444 case 'i': 445 type = 'I'; 446 /*FALLTHROUGH*/ 447 case 'I': 448 break; 449 case 'a': 450 type = 'A'; 451 /*FALLTHROUGH*/ 452 case 'A': 453 break; 454 case 'd': 455 type = 'D'; 456 /*FALLTHROUGH*/ 457 case 'D': 458 /* can't handle yet */ 459 default: 460 return (FTP_PROTOCOL_ERROR); 461 } 462 if ((e = ftp_cmd(conn, "TYPE %c\r\n", type)) != FTP_OK) 463 return (e); 464 465 return (FTP_OK); 466 } 467 468 /* 469 * Request and parse file stats 470 */ 471 static int 472 ftp_stat(conn_t *conn, const char *file, struct url_stat *us) 473 { 474 char *ln; 475 const char *filename; 476 size_t filenamelen; 477 int type; 478 struct tm tm; 479 time_t t; 480 int e; 481 482 us->size = -1; 483 us->atime = us->mtime = 0; 484 485 filename = ftp_filename(file, &filenamelen, &type, 0); 486 487 if ((e = ftp_mode_type(conn, 0, type)) != FTP_OK) { 488 ftp_seterr(e); 489 return (-1); 490 } 491 492 e = ftp_cmd(conn, "SIZE %.*s\r\n", filenamelen, filename); 493 if (e != FTP_FILE_STATUS) { 494 ftp_seterr(e); 495 return (-1); 496 } 497 for (ln = conn->buf + 4; *ln && isspace((unsigned char)*ln); ln++) 498 /* nothing */ ; 499 for (us->size = 0; *ln && isdigit((unsigned char)*ln); ln++) 500 us->size = us->size * 10 + *ln - '0'; 501 if (*ln && !isspace((unsigned char)*ln)) { 502 ftp_seterr(FTP_PROTOCOL_ERROR); 503 us->size = -1; 504 return (-1); 505 } 506 if (us->size == 0) 507 us->size = -1; 508 509 e = ftp_cmd(conn, "MDTM %.*s\r\n", filenamelen, filename); 510 if (e != FTP_FILE_STATUS) { 511 ftp_seterr(e); 512 return (-1); 513 } 514 for (ln = conn->buf + 4; *ln && isspace((unsigned char)*ln); ln++) 515 /* nothing */ ; 516 switch (strspn(ln, "0123456789")) { 517 case 14: 518 break; 519 case 15: 520 ln++; 521 ln[0] = '2'; 522 ln[1] = '0'; 523 break; 524 default: 525 ftp_seterr(FTP_PROTOCOL_ERROR); 526 return (-1); 527 } 528 if (sscanf(ln, "%04d%02d%02d%02d%02d%02d", 529 &tm.tm_year, &tm.tm_mon, &tm.tm_mday, 530 &tm.tm_hour, &tm.tm_min, &tm.tm_sec) != 6) { 531 ftp_seterr(FTP_PROTOCOL_ERROR); 532 return (-1); 533 } 534 tm.tm_mon--; 535 tm.tm_year -= 1900; 536 tm.tm_isdst = -1; 537 t = timegm(&tm); 538 if (t == (time_t)-1) 539 t = time(NULL); 540 us->mtime = t; 541 us->atime = t; 542 543 return (0); 544 } 545 546 /* 547 * I/O functions for FTP 548 */ 549 struct ftpio { 550 conn_t *cconn; /* Control connection */ 551 conn_t *dconn; /* Data connection */ 552 int dir; /* Direction */ 553 int eof; /* EOF reached */ 554 int err; /* Error code */ 555 }; 556 557 static ssize_t ftp_readfn(void *, void *, size_t); 558 static ssize_t ftp_writefn(void *, const void *, size_t); 559 static void ftp_closefn(void *); 560 561 static ssize_t 562 ftp_readfn(void *v, void *buf, size_t len) 563 { 564 struct ftpio *io; 565 ssize_t r; 566 567 io = (struct ftpio *)v; 568 if (io == NULL) { 569 errno = EBADF; 570 return (-1); 571 } 572 if (io->cconn == NULL || io->dconn == NULL || io->dir == O_WRONLY) { 573 errno = EBADF; 574 return (-1); 575 } 576 if (io->err) { 577 errno = io->err; 578 return (-1); 579 } 580 if (io->eof) 581 return (0); 582 r = fetch_read(io->dconn, buf, len); 583 if (r > 0) 584 return (r); 585 if (r == 0) { 586 io->eof = 1; 587 return (0); 588 } 589 if (errno != EINTR) 590 io->err = errno; 591 return (-1); 592 } 593 594 static ssize_t 595 ftp_writefn(void *v, const void *buf, size_t len) 596 { 597 struct ftpio *io; 598 ssize_t w; 599 600 io = (struct ftpio *)v; 601 if (io == NULL) { 602 errno = EBADF; 603 return (-1); 604 } 605 if (io->cconn == NULL || io->dconn == NULL || io->dir == O_RDONLY) { 606 errno = EBADF; 607 return (-1); 608 } 609 if (io->err) { 610 errno = io->err; 611 return (-1); 612 } 613 w = fetch_write(io->dconn, buf, len); 614 if (w >= 0) 615 return (w); 616 if (errno != EINTR) 617 io->err = errno; 618 return (-1); 619 } 620 621 static int 622 ftp_disconnect(conn_t *conn) 623 { 624 ftp_cmd(conn, "QUIT\r\n"); 625 return fetch_close(conn); 626 } 627 628 static void 629 ftp_closefn(void *v) 630 { 631 struct ftpio *io; 632 633 io = (struct ftpio *)v; 634 if (io == NULL) { 635 errno = EBADF; 636 return; 637 } 638 if (io->dir == -1) 639 return; 640 if (io->cconn == NULL || io->dconn == NULL) { 641 errno = EBADF; 642 return; 643 } 644 fetch_close(io->dconn); 645 io->dconn = NULL; 646 io->dir = -1; 647 (void)ftp_chkerr(io->cconn); 648 fetch_cache_put(io->cconn, ftp_disconnect); 649 free(io); 650 return; 651 } 652 653 static fetchIO * 654 ftp_setup(conn_t *cconn, conn_t *dconn, int mode) 655 { 656 struct ftpio *io; 657 fetchIO *f; 658 659 if (cconn == NULL || dconn == NULL) 660 return (NULL); 661 if ((io = malloc(sizeof(*io))) == NULL) 662 return (NULL); 663 io->cconn = cconn; 664 io->dconn = dconn; 665 io->dir = mode; 666 io->eof = io->err = 0; 667 f = fetchIO_unopen(io, ftp_readfn, ftp_writefn, ftp_closefn); 668 if (f == NULL) 669 free(io); 670 return (f); 671 } 672 673 /* 674 * Transfer file 675 */ 676 static fetchIO * 677 ftp_transfer(conn_t *conn, const char *oper, const char *file, const char *op_arg, 678 int mode, off_t offset, const char *flags) 679 { 680 union anonymous { 681 struct sockaddr_storage ss; 682 struct sockaddr sa; 683 struct sockaddr_in6 sin6; 684 struct sockaddr_in sin4; 685 } u; 686 const char *bindaddr; 687 const char *filename; 688 size_t filenamelen; 689 int type; 690 int low, pasv, verbose; 691 int e, sd = -1; 692 socklen_t l; 693 char *s; 694 fetchIO *df; 695 696 /* check flags */ 697 low = CHECK_FLAG('l'); 698 pasv = !CHECK_FLAG('a'); 699 verbose = CHECK_FLAG('v'); 700 701 /* passive mode */ 702 if (!pasv) 703 pasv = ((s = getenv("FTP_PASSIVE_MODE")) != NULL && 704 strncasecmp(s, "no", 2) != 0); 705 706 /* isolate filename */ 707 filename = ftp_filename(file, &filenamelen, &type, op_arg != NULL); 708 709 /* set transfer mode and data type */ 710 if ((e = ftp_mode_type(conn, 0, type)) != FTP_OK) 711 goto ouch; 712 713 /* find our own address, bind, and listen */ 714 l = sizeof(u.ss); 715 if (getsockname(conn->sd, &u.sa, &l) == -1) 716 goto sysouch; 717 if (u.ss.ss_family == AF_INET6) 718 unmappedaddr(&u.sin6, &l); 719 720 retry_mode: 721 722 /* open data socket */ 723 if ((sd = socket(u.ss.ss_family, SOCK_STREAM, IPPROTO_TCP)) == -1) { 724 fetch_syserr(); 725 return (NULL); 726 } 727 728 if (pasv) { 729 unsigned char addr[64]; 730 char *ln, *p; 731 unsigned int i; 732 int port; 733 734 /* send PASV command */ 735 if (verbose) 736 fetch_info("setting passive mode"); 737 switch (u.ss.ss_family) { 738 case AF_INET: 739 if ((e = ftp_cmd(conn, "PASV\r\n")) != FTP_PASSIVE_MODE) 740 goto ouch; 741 break; 742 case AF_INET6: 743 if ((e = ftp_cmd(conn, "EPSV\r\n")) != FTP_EPASSIVE_MODE) { 744 if (e == -1) 745 goto ouch; 746 if ((e = ftp_cmd(conn, "LPSV\r\n")) != 747 FTP_LPASSIVE_MODE) 748 goto ouch; 749 } 750 break; 751 default: 752 e = FTP_PROTOCOL_ERROR; /* XXX: error code should be prepared */ 753 goto ouch; 754 } 755 756 /* 757 * Find address and port number. The reply to the PASV command 758 * is IMHO the one and only weak point in the FTP protocol. 759 */ 760 ln = conn->buf; 761 switch (e) { 762 case FTP_PASSIVE_MODE: 763 case FTP_LPASSIVE_MODE: 764 for (p = ln + 3; *p && !isdigit((unsigned char)*p); p++) 765 /* nothing */ ; 766 if (!*p) { 767 e = FTP_PROTOCOL_ERROR; 768 goto ouch; 769 } 770 l = (e == FTP_PASSIVE_MODE ? 6 : 21); 771 for (i = 0; *p && i < l; i++, p++) 772 addr[i] = (unsigned char)strtol(p, &p, 10); 773 if (i < l) { 774 e = FTP_PROTOCOL_ERROR; 775 goto ouch; 776 } 777 break; 778 case FTP_EPASSIVE_MODE: 779 for (p = ln + 3; *p && *p != '('; p++) 780 /* nothing */ ; 781 if (!*p) { 782 e = FTP_PROTOCOL_ERROR; 783 goto ouch; 784 } 785 ++p; 786 if (sscanf(p, "%c%c%c%d%c", &addr[0], &addr[1], &addr[2], 787 &port, &addr[3]) != 5 || 788 addr[0] != addr[1] || 789 addr[0] != addr[2] || addr[0] != addr[3]) { 790 e = FTP_PROTOCOL_ERROR; 791 goto ouch; 792 } 793 break; 794 case FTP_SYNTAX_ERROR: 795 if (verbose) 796 fetch_info("passive mode failed"); 797 /* Close socket and retry with passive mode. */ 798 pasv = 0; 799 close(sd); 800 sd = -1; 801 goto retry_mode; 802 } 803 804 /* seek to required offset */ 805 if (offset) 806 if (ftp_cmd(conn, "REST %lu\r\n", (unsigned long)offset) != FTP_FILE_OK) 807 goto sysouch; 808 809 /* construct sockaddr for data socket */ 810 l = sizeof(u.ss); 811 if (getpeername(conn->sd, &u.sa, &l) == -1) 812 goto sysouch; 813 if (u.ss.ss_family == AF_INET6) 814 unmappedaddr(&u.sin6, &l); 815 switch (u.ss.ss_family) { 816 case AF_INET6: 817 if (e == FTP_EPASSIVE_MODE) 818 u.sin6.sin6_port = htons(port); 819 else { 820 memcpy(&u.sin6.sin6_addr, addr + 2, 16); 821 memcpy(&u.sin6.sin6_port, addr + 19, 2); 822 } 823 break; 824 case AF_INET: 825 if (e == FTP_EPASSIVE_MODE) 826 u.sin4.sin_port = htons(port); 827 else { 828 memcpy(&u.sin4.sin_addr, addr, 4); 829 memcpy(&u.sin4.sin_port, addr + 4, 2); 830 } 831 break; 832 default: 833 e = FTP_PROTOCOL_ERROR; /* XXX: error code should be prepared */ 834 break; 835 } 836 837 /* connect to data port */ 838 if (verbose) 839 fetch_info("opening data connection"); 840 bindaddr = getenv("FETCH_BIND_ADDRESS"); 841 if (bindaddr != NULL && *bindaddr != '\0' && 842 fetch_bind(sd, u.ss.ss_family, bindaddr) != 0) 843 goto sysouch; 844 if (connect(sd, &u.sa, l) == -1) 845 goto sysouch; 846 847 /* make the server initiate the transfer */ 848 if (verbose) 849 fetch_info("initiating transfer"); 850 if (op_arg) 851 e = ftp_cmd(conn, "%s%s%s\r\n", oper, *op_arg ? " " : "", op_arg); 852 else 853 e = ftp_cmd(conn, "%s %.*s\r\n", oper, 854 filenamelen, filename); 855 if (e != FTP_CONNECTION_ALREADY_OPEN && e != FTP_OPEN_DATA_CONNECTION) 856 goto ouch; 857 858 } else { 859 uint32_t a; 860 uint16_t p; 861 #if defined(IPV6_PORTRANGE) || defined(IP_PORTRANGE) 862 int arg; 863 #endif 864 int d; 865 char hname[INET6_ADDRSTRLEN]; 866 867 switch (u.ss.ss_family) { 868 case AF_INET6: 869 u.sin6.sin6_port = 0; 870 #ifdef IPV6_PORTRANGE 871 arg = low ? IPV6_PORTRANGE_DEFAULT : IPV6_PORTRANGE_HIGH; 872 if (setsockopt(sd, IPPROTO_IPV6, IPV6_PORTRANGE, 873 &arg, (socklen_t)sizeof(arg)) == -1) 874 goto sysouch; 875 #endif 876 break; 877 case AF_INET: 878 u.sin4.sin_port = 0; 879 #ifdef IP_PORTRANGE 880 arg = low ? IP_PORTRANGE_DEFAULT : IP_PORTRANGE_HIGH; 881 if (setsockopt(sd, IPPROTO_IP, IP_PORTRANGE, 882 &arg, (socklen_t)sizeof(arg)) == -1) 883 goto sysouch; 884 #endif 885 break; 886 } 887 if (verbose) 888 fetch_info("binding data socket"); 889 if (bind(sd, &u.sa, l) == -1) 890 goto sysouch; 891 if (listen(sd, 1) == -1) 892 goto sysouch; 893 894 /* find what port we're on and tell the server */ 895 if (getsockname(sd, &u.sa, &l) == -1) 896 goto sysouch; 897 switch (u.ss.ss_family) { 898 case AF_INET: 899 a = ntohl(u.sin4.sin_addr.s_addr); 900 p = ntohs(u.sin4.sin_port); 901 e = ftp_cmd(conn, "PORT %d,%d,%d,%d,%d,%d\r\n", 902 (a >> 24) & 0xff, (a >> 16) & 0xff, 903 (a >> 8) & 0xff, a & 0xff, 904 ((unsigned int)p >> 8) & 0xff, p & 0xff); 905 break; 906 case AF_INET6: 907 e = -1; 908 u.sin6.sin6_scope_id = 0; 909 if (getnameinfo(&u.sa, l, 910 hname, (socklen_t)sizeof(hname), 911 NULL, 0, NI_NUMERICHOST) == 0) { 912 e = ftp_cmd(conn, "EPRT |%d|%s|%d|\r\n", 2, hname, 913 htons(u.sin6.sin6_port)); 914 if (e == -1) 915 goto ouch; 916 } 917 if (e != FTP_OK) { 918 uint8_t aa[sizeof(u.sin6.sin6_addr)]; 919 memcpy(aa, &u.sin6.sin6_addr, sizeof(aa)); 920 p = ntohs(u.sin6.sin6_port); 921 e = ftp_cmd(conn, 922 "LPRT %d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d\r\n", 923 6, 16, 924 aa[ 0], aa[ 1], aa[ 2], aa[ 3], 925 aa[ 4], aa[ 5], aa[ 6], aa[ 7], 926 aa[ 8], aa[ 9], aa[10], aa[11], 927 aa[12], aa[13], aa[14], aa[15], 928 2, 929 ((unsigned int)p >> 8) & 0xff, p & 0xff); 930 } 931 break; 932 default: 933 e = FTP_PROTOCOL_ERROR; /* XXX: error code should be prepared */ 934 goto ouch; 935 } 936 if (e != FTP_OK) 937 goto ouch; 938 939 /* seek to required offset */ 940 if (offset) 941 if (ftp_cmd(conn, "REST %llu\r\n", (unsigned long long)offset) != FTP_FILE_OK) 942 goto sysouch; 943 944 /* make the server initiate the transfer */ 945 if (verbose) 946 fetch_info("initiating transfer"); 947 if (op_arg) 948 e = ftp_cmd(conn, "%s%s%s\r\n", oper, *op_arg ? " " : "", op_arg); 949 else 950 e = ftp_cmd(conn, "%s %.*s\r\n", oper, 951 filenamelen, filename); 952 if (e != FTP_CONNECTION_ALREADY_OPEN && e != FTP_OPEN_DATA_CONNECTION) 953 goto ouch; 954 955 /* accept the incoming connection and go to town */ 956 if ((d = accept(sd, NULL, NULL)) == -1) 957 goto sysouch; 958 close(sd); 959 sd = d; 960 } 961 962 if ((df = ftp_setup(conn, fetch_reopen(sd), mode)) == NULL) 963 goto sysouch; 964 return (df); 965 966 sysouch: 967 fetch_syserr(); 968 if (sd >= 0) 969 close(sd); 970 return (NULL); 971 972 ouch: 973 if (e != -1) 974 ftp_seterr(e); 975 if (sd >= 0) 976 close(sd); 977 return (NULL); 978 } 979 980 /* 981 * Authenticate 982 */ 983 static int 984 ftp_authenticate(conn_t *conn, struct url *url, struct url *purl) 985 { 986 const char *user, *pwd, *login_name; 987 char pbuf[URL_USERLEN + 1 + URL_HOSTLEN + 1]; 988 int e, len; 989 990 /* XXX FTP_AUTH, and maybe .netrc */ 991 992 /* send user name and password */ 993 if (url->user[0] == '\0') 994 fetch_netrc_auth(url); 995 user = url->user; 996 if (*user == '\0') 997 user = getenv("FTP_LOGIN"); 998 if (user == NULL || *user == '\0') 999 user = FTP_ANONYMOUS_USER; 1000 if (purl && url->port == fetch_default_port(url->scheme)) 1001 e = ftp_cmd(conn, "USER %s@%s\r\n", user, url->host); 1002 else if (purl) 1003 e = ftp_cmd(conn, "USER %s@%s@%d\r\n", user, url->host, url->port); 1004 else 1005 e = ftp_cmd(conn, "USER %s\r\n", user); 1006 1007 /* did the server request a password? */ 1008 if (e == FTP_NEED_PASSWORD) { 1009 pwd = url->pwd; 1010 if (*pwd == '\0') 1011 pwd = getenv("FTP_PASSWORD"); 1012 if (pwd == NULL || *pwd == '\0') { 1013 if ((login_name = getlogin()) == 0) 1014 login_name = FTP_ANONYMOUS_USER; 1015 if ((len = snprintf(pbuf, URL_USERLEN + 2, "%s@", login_name)) < 0) 1016 len = 0; 1017 else if (len > URL_USERLEN + 1) 1018 len = URL_USERLEN + 1; 1019 gethostname(pbuf + len, sizeof(pbuf) - len); 1020 /* MAXHOSTNAMELEN can differ from URL_HOSTLEN + 1 */ 1021 pbuf[sizeof(pbuf) - 1] = '\0'; 1022 pwd = pbuf; 1023 } 1024 e = ftp_cmd(conn, "PASS %s\r\n", pwd); 1025 } 1026 1027 return (e); 1028 } 1029 1030 /* 1031 * Log on to FTP server 1032 */ 1033 static conn_t * 1034 ftp_connect(struct url *url, struct url *purl, const char *flags) 1035 { 1036 conn_t *conn; 1037 int e, direct, verbose; 1038 #ifdef INET6 1039 int af = AF_UNSPEC; 1040 #else 1041 int af = AF_INET; 1042 #endif 1043 1044 direct = CHECK_FLAG('d'); 1045 verbose = CHECK_FLAG('v'); 1046 if (CHECK_FLAG('4')) 1047 af = AF_INET; 1048 else if (CHECK_FLAG('6')) 1049 af = AF_INET6; 1050 1051 if (direct) 1052 purl = NULL; 1053 1054 /* check for proxy */ 1055 if (purl) { 1056 /* XXX proxy authentication! */ 1057 /* XXX connetion caching */ 1058 if (!purl->port) 1059 purl->port = fetch_default_port(purl->scheme); 1060 1061 conn = fetch_connect(purl, af, verbose); 1062 } else { 1063 /* no proxy, go straight to target */ 1064 if (!url->port) 1065 url->port = fetch_default_port(url->scheme); 1066 1067 while ((conn = fetch_cache_get(url, af)) != NULL) { 1068 e = ftp_cmd(conn, "NOOP\r\n"); 1069 if (e == FTP_OK) 1070 return conn; 1071 fetch_close(conn); 1072 } 1073 conn = fetch_connect(url, af, verbose); 1074 purl = NULL; 1075 } 1076 1077 /* check connection */ 1078 if (conn == NULL) 1079 /* fetch_connect() has already set an error code */ 1080 return (NULL); 1081 1082 /* expect welcome message */ 1083 if ((e = ftp_chkerr(conn)) != FTP_SERVICE_READY) 1084 goto fouch; 1085 1086 /* authenticate */ 1087 if ((e = ftp_authenticate(conn, url, purl)) != FTP_LOGGED_IN) 1088 goto fouch; 1089 1090 /* TODO: Request extended features supported, if any (RFC 3659). */ 1091 1092 /* done */ 1093 return (conn); 1094 1095 fouch: 1096 if (e != -1) 1097 ftp_seterr(e); 1098 fetch_close(conn); 1099 return (NULL); 1100 } 1101 1102 /* 1103 * Check the proxy settings 1104 */ 1105 static struct url * 1106 ftp_get_proxy(struct url * url, const char *flags) 1107 { 1108 struct url *purl; 1109 char *p, *fp, *FP, *hp, *HP; 1110 1111 if (flags != NULL && strchr(flags, 'd') != NULL) 1112 return NULL; 1113 if (fetch_no_proxy_match(url->host)) 1114 return NULL; 1115 1116 FP = getenv("FTP_PROXY"); 1117 fp = getenv("ftp_proxy"); 1118 HP = getenv("HTTP_PROXY"); 1119 hp = getenv("http_proxy"); 1120 1121 if ((((p = FP) || (p = fp) || (p = HP) || (p = hp))) && 1122 *p && (purl = fetchParseURL(p)) != NULL) { 1123 if (!*purl->scheme) { 1124 if (fp || FP) 1125 strcpy(purl->scheme, SCHEME_FTP); 1126 else 1127 strcpy(purl->scheme, SCHEME_HTTP); 1128 } 1129 if (!purl->port) 1130 purl->port = fetch_default_proxy_port(purl->scheme); 1131 if (strcasecmp(purl->scheme, SCHEME_FTP) == 0 || 1132 strcasecmp(purl->scheme, SCHEME_HTTP) == 0) 1133 return purl; 1134 fetchFreeURL(purl); 1135 } 1136 return NULL; 1137 } 1138 1139 /* 1140 * Process an FTP request 1141 */ 1142 fetchIO * 1143 ftp_request(struct url *url, const char *op, const char *op_arg, 1144 struct url_stat *us, struct url *purl, const char *flags) 1145 { 1146 fetchIO *f; 1147 char *path; 1148 conn_t *conn; 1149 int if_modified_since, oflag; 1150 struct url_stat local_us; 1151 1152 /* check if we should use HTTP instead */ 1153 if (purl && strcasecmp(purl->scheme, SCHEME_HTTP) == 0) { 1154 if (strcmp(op, "STAT") == 0) 1155 return (http_request(url, "HEAD", us, purl, flags)); 1156 else if (strcmp(op, "RETR") == 0) 1157 return (http_request(url, "GET", us, purl, flags)); 1158 /* 1159 * Our HTTP code doesn't support PUT requests yet, so try 1160 * a direct connection. 1161 */ 1162 } 1163 1164 /* connect to server */ 1165 conn = ftp_connect(url, purl, flags); 1166 if (purl) 1167 fetchFreeURL(purl); 1168 if (conn == NULL) 1169 return (NULL); 1170 1171 if ((path = fetchUnquotePath(url)) == NULL) { 1172 fetch_syserr(); 1173 return NULL; 1174 } 1175 1176 /* change directory */ 1177 if (ftp_cwd(conn, path, op_arg != NULL) == -1) { 1178 free(path); 1179 return (NULL); 1180 } 1181 1182 if_modified_since = CHECK_FLAG('i'); 1183 if (if_modified_since && us == NULL) 1184 us = &local_us; 1185 1186 /* stat file */ 1187 if (us && ftp_stat(conn, path, us) == -1 1188 && fetchLastErrCode != FETCH_PROTO 1189 && fetchLastErrCode != FETCH_UNAVAIL) { 1190 free(path); 1191 return (NULL); 1192 } 1193 1194 if (if_modified_since && url->last_modified > 0 && 1195 url->last_modified >= us->mtime) { 1196 free(path); 1197 fetchLastErrCode = FETCH_UNCHANGED; 1198 snprintf(fetchLastErrString, MAXERRSTRING, "Unchanged"); 1199 return NULL; 1200 } 1201 1202 /* just a stat */ 1203 if (strcmp(op, "STAT") == 0) { 1204 free(path); 1205 return fetchIO_unopen(NULL, NULL, NULL, NULL); 1206 } 1207 if (strcmp(op, "STOR") == 0 || strcmp(op, "APPE") == 0) 1208 oflag = O_WRONLY; 1209 else 1210 oflag = O_RDONLY; 1211 1212 /* initiate the transfer */ 1213 f = (ftp_transfer(conn, op, path, op_arg, oflag, url->offset, flags)); 1214 free(path); 1215 return f; 1216 } 1217 1218 /* 1219 * Get and stat file 1220 */ 1221 fetchIO * 1222 fetchXGetFTP(struct url *url, struct url_stat *us, const char *flags) 1223 { 1224 return (ftp_request(url, "RETR", NULL, us, ftp_get_proxy(url, flags), flags)); 1225 } 1226 1227 /* 1228 * Get file 1229 */ 1230 fetchIO * 1231 fetchGetFTP(struct url *url, const char *flags) 1232 { 1233 return (fetchXGetFTP(url, NULL, flags)); 1234 } 1235 1236 /* 1237 * Put file 1238 */ 1239 fetchIO * 1240 fetchPutFTP(struct url *url, const char *flags) 1241 { 1242 return (ftp_request(url, CHECK_FLAG('a') ? "APPE" : "STOR", NULL, NULL, 1243 ftp_get_proxy(url, flags), flags)); 1244 } 1245 1246 /* 1247 * Get file stats 1248 */ 1249 int 1250 fetchStatFTP(struct url *url, struct url_stat *us, const char *flags) 1251 { 1252 fetchIO *f; 1253 1254 f = ftp_request(url, "STAT", NULL, us, ftp_get_proxy(url, flags), flags); 1255 if (f == NULL) 1256 return (-1); 1257 fetchIO_close(f); 1258 return (0); 1259 } 1260 1261 /* 1262 * List a directory 1263 */ 1264 int 1265 fetchListFTP(struct url_list *ue, struct url *url, const char *pattern, const char *flags) 1266 { 1267 fetchIO *f; 1268 char buf[2 * PATH_MAX], *eol, *eos; 1269 ssize_t len; 1270 size_t cur_off; 1271 int ret; 1272 1273 /* XXX What about proxies? */ 1274 if (pattern == NULL || strcmp(pattern, "*") == 0) 1275 pattern = ""; 1276 f = ftp_request(url, "NLST", pattern, NULL, ftp_get_proxy(url, flags), flags); 1277 if (f == NULL) 1278 return -1; 1279 1280 cur_off = 0; 1281 ret = 0; 1282 1283 while ((len = fetchIO_read(f, buf + cur_off, sizeof(buf) - cur_off)) > 0) { 1284 cur_off += len; 1285 while ((eol = memchr(buf, '\n', cur_off)) != NULL) { 1286 if (len == eol - buf) 1287 break; 1288 if (eol != buf) { 1289 if (eol[-1] == '\r') 1290 eos = eol - 1; 1291 else 1292 eos = eol; 1293 *eos = '\0'; 1294 ret = fetch_add_entry(ue, url, buf, 0); 1295 if (ret) 1296 break; 1297 cur_off -= eol - buf + 1; 1298 memmove(buf, eol + 1, cur_off); 1299 } 1300 } 1301 if (ret) 1302 break; 1303 } 1304 if (cur_off != 0 || len < 0) { 1305 /* Not RFC conform, bail out. */ 1306 fetchIO_close(f); 1307 return -1; 1308 } 1309 fetchIO_close(f); 1310 return ret; 1311 } 1312