1 /* $NetBSD: ftp.c,v 1.7 2014/01/07 02:13:00 joerg 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
unmappedaddr(struct sockaddr_in6 * sin6,socklen_t * len)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
ftp_chkerr(conn_t * conn)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 __printflike(2, 3)
202 static int
ftp_cmd(conn_t * conn,const char * fmt,...)203 ftp_cmd(conn_t *conn, const char *fmt, ...)
204 {
205 va_list ap;
206 size_t len;
207 char *msg;
208 ssize_t r;
209
210 va_start(ap, fmt);
211 len = vasprintf(&msg, fmt, ap);
212 va_end(ap);
213
214 if (msg == NULL) {
215 errno = ENOMEM;
216 fetch_syserr();
217 return (-1);
218 }
219
220 r = fetch_write(conn, msg, len);
221 free(msg);
222
223 if (r == -1) {
224 fetch_syserr();
225 return (-1);
226 }
227
228 return (ftp_chkerr(conn));
229 }
230
231 /*
232 * Return a pointer to the filename part of a path
233 */
234 static const char *
ftp_filename(const char * file,size_t * len,int * type,int subdir)235 ftp_filename(const char *file, size_t *len, int *type, int subdir)
236 {
237 const char *s;
238
239 if ((s = strrchr(file, '/')) == NULL || subdir)
240 s = file;
241 else
242 s = s + 1;
243 *len = strlen(s);
244 if (*len > 7 && strncmp(s + *len - 7, ";type=", 6) == 0) {
245 *type = s[*len - 1];
246 *len -= 7;
247 } else {
248 *type = '\0';
249 }
250 return (s);
251 }
252
253 /*
254 * Get current working directory from the reply to a CWD, PWD or CDUP
255 * command.
256 */
257 static int
ftp_pwd(conn_t * conn,char ** pwd)258 ftp_pwd(conn_t *conn, char **pwd)
259 {
260 char *src, *dst, *end;
261 int q;
262 size_t len;
263
264 if (conn->err != FTP_WORKING_DIRECTORY &&
265 conn->err != FTP_FILE_ACTION_OK)
266 return (FTP_PROTOCOL_ERROR);
267 end = conn->buf + conn->buflen;
268 src = conn->buf + 4;
269 if (src >= end || *src++ != '"')
270 return (FTP_PROTOCOL_ERROR);
271 len = end - src + 1;
272 *pwd = malloc(len);
273 if (*pwd == NULL)
274 return (FTP_PROTOCOL_ERROR);
275 for (q = 0, dst = *pwd; src < end; ++src) {
276 if (!q && *src == '"')
277 q = 1;
278 else if (q && *src != '"')
279 break;
280 else if (q)
281 *dst++ = '"', q = 0;
282 else
283 *dst++ = *src;
284 }
285 *dst = '\0';
286 if (**pwd != '/') {
287 free(*pwd);
288 *pwd = NULL;
289 return (FTP_PROTOCOL_ERROR);
290 }
291 return (FTP_OK);
292 }
293
294 /*
295 * Change working directory to the directory that contains the specified
296 * file.
297 */
298 static int
ftp_cwd(conn_t * conn,const char * path,int subdir)299 ftp_cwd(conn_t *conn, const char *path, int subdir)
300 {
301 const char *beg, *end;
302 char *pwd, *dst;
303 int e;
304 size_t i, len;
305
306 if (*path != '/') {
307 ftp_seterr(501);
308 return (-1);
309 }
310 ++path;
311
312 /* Simple case: still in the home directory and no directory change. */
313 if (conn->ftp_home == NULL && strchr(path, '/') == NULL &&
314 (!subdir || *path == '\0'))
315 return 0;
316
317 if ((e = ftp_cmd(conn, "PWD\r\n")) != FTP_WORKING_DIRECTORY ||
318 (e = ftp_pwd(conn, &pwd)) != FTP_OK) {
319 ftp_seterr(e);
320 return (-1);
321 }
322 if (conn->ftp_home == NULL && (conn->ftp_home = strdup(pwd)) == NULL) {
323 fetch_syserr();
324 free(pwd);
325 return (-1);
326 }
327 if (*path == '/') {
328 while (path[1] == '/')
329 ++path;
330 dst = strdup(path);
331 } else if (strcmp(conn->ftp_home, "/") == 0) {
332 dst = strdup(path - 1);
333 } else {
334 asprintf(&dst, "%s/%s", conn->ftp_home, path);
335 }
336 if (dst == NULL) {
337 fetch_syserr();
338 free(pwd);
339 return (-1);
340 }
341
342 if (subdir)
343 end = dst + strlen(dst);
344 else
345 end = strrchr(dst, '/');
346
347 for (;;) {
348 len = strlen(pwd);
349
350 /* Look for a common prefix between PWD and dir to fetch. */
351 for (i = 0; i <= len && i <= (size_t)(end - dst); ++i)
352 if (pwd[i] != dst[i])
353 break;
354 /* Keep going up a dir until we have a matching prefix. */
355 if (strcmp(pwd, "/") == 0)
356 break;
357 if (pwd[i] == '\0' && (dst[i - 1] == '/' || dst[i] == '/'))
358 break;
359 free(pwd);
360 if ((e = ftp_cmd(conn, "CDUP\r\n")) != FTP_FILE_ACTION_OK ||
361 (e = ftp_cmd(conn, "PWD\r\n")) != FTP_WORKING_DIRECTORY ||
362 (e = ftp_pwd(conn, &pwd)) != FTP_OK) {
363 ftp_seterr(e);
364 free(dst);
365 return (-1);
366 }
367 }
368 free(pwd);
369
370 #ifdef FTP_COMBINE_CWDS
371 /* Skip leading slashes, even "////". */
372 for (beg = dst + i; beg < end && *beg == '/'; ++beg, ++i)
373 /* nothing */ ;
374
375 /* If there is no trailing dir, we're already there. */
376 if (beg >= end) {
377 free(dst);
378 return (0);
379 }
380
381 /* Change to the directory all in one chunk (e.g., foo/bar/baz). */
382 e = ftp_cmd(conn, "CWD %.*s\r\n", (int)(end - beg), beg);
383 if (e == FTP_FILE_ACTION_OK) {
384 free(dst);
385 return (0);
386 }
387 #endif /* FTP_COMBINE_CWDS */
388
389 /* That didn't work so go back to legacy behavior (multiple CWDs). */
390 for (beg = dst + i; beg < end; beg = dst + i + 1) {
391 while (*beg == '/')
392 ++beg, ++i;
393 for (++i; dst + i < end && dst[i] != '/'; ++i)
394 /* nothing */ ;
395 e = ftp_cmd(conn, "CWD %.*s\r\n", (int)(dst + i - beg), beg);
396 if (e != FTP_FILE_ACTION_OK) {
397 free(dst);
398 ftp_seterr(e);
399 return (-1);
400 }
401 }
402 free(dst);
403 return (0);
404 }
405
406 /*
407 * Set transfer mode and data type
408 */
409 static int
ftp_mode_type(conn_t * conn,int mode,int type)410 ftp_mode_type(conn_t *conn, int mode, int type)
411 {
412 int e;
413
414 switch (mode) {
415 case 0:
416 case 's':
417 mode = 'S';
418 /*FALLTHROUGH*/
419 case 'S':
420 break;
421 default:
422 return (FTP_PROTOCOL_ERROR);
423 }
424 if ((e = ftp_cmd(conn, "MODE %c\r\n", mode)) != FTP_OK) {
425 if (mode == 'S') {
426 /*
427 * Stream mode is supposed to be the default - so
428 * much so that some servers not only do not
429 * support any other mode, but do not support the
430 * MODE command at all.
431 *
432 * If "MODE S" fails, it is unlikely that we
433 * previously succeeded in setting a different
434 * mode. Therefore, we simply hope that the
435 * server is already in the correct mode, and
436 * silently ignore the failure.
437 */
438 } else {
439 return (e);
440 }
441 }
442
443 switch (type) {
444 case 0:
445 case 'i':
446 type = 'I';
447 /*FALLTHROUGH*/
448 case 'I':
449 break;
450 case 'a':
451 type = 'A';
452 /*FALLTHROUGH*/
453 case 'A':
454 break;
455 case 'd':
456 type = 'D';
457 /*FALLTHROUGH*/
458 case 'D':
459 /* can't handle yet */
460 default:
461 return (FTP_PROTOCOL_ERROR);
462 }
463 if ((e = ftp_cmd(conn, "TYPE %c\r\n", type)) != FTP_OK)
464 return (e);
465
466 return (FTP_OK);
467 }
468
469 /*
470 * Request and parse file stats
471 */
472 static int
ftp_stat(conn_t * conn,const char * file,struct url_stat * us)473 ftp_stat(conn_t *conn, const char *file, struct url_stat *us)
474 {
475 char *ln;
476 const char *filename;
477 size_t filenamelen;
478 int type;
479 struct tm tm;
480 time_t t;
481 int e;
482
483 us->size = -1;
484 us->atime = us->mtime = 0;
485
486 filename = ftp_filename(file, &filenamelen, &type, 0);
487
488 if ((e = ftp_mode_type(conn, 0, type)) != FTP_OK) {
489 ftp_seterr(e);
490 return (-1);
491 }
492
493 e = ftp_cmd(conn, "SIZE %.*s\r\n", (int)filenamelen, filename);
494 if (e != FTP_FILE_STATUS) {
495 ftp_seterr(e);
496 return (-1);
497 }
498 for (ln = conn->buf + 4; *ln && isspace((unsigned char)*ln); ln++)
499 /* nothing */ ;
500 for (us->size = 0; *ln && isdigit((unsigned char)*ln); ln++)
501 us->size = us->size * 10 + *ln - '0';
502 if (*ln && !isspace((unsigned char)*ln)) {
503 ftp_seterr(FTP_PROTOCOL_ERROR);
504 us->size = -1;
505 return (-1);
506 }
507 if (us->size == 0)
508 us->size = -1;
509
510 e = ftp_cmd(conn, "MDTM %.*s\r\n", (int)filenamelen, filename);
511 if (e != FTP_FILE_STATUS) {
512 ftp_seterr(e);
513 return (-1);
514 }
515 for (ln = conn->buf + 4; *ln && isspace((unsigned char)*ln); ln++)
516 /* nothing */ ;
517 switch (strspn(ln, "0123456789")) {
518 case 14:
519 break;
520 case 15:
521 ln++;
522 ln[0] = '2';
523 ln[1] = '0';
524 break;
525 default:
526 ftp_seterr(FTP_PROTOCOL_ERROR);
527 return (-1);
528 }
529 if (sscanf(ln, "%04d%02d%02d%02d%02d%02d",
530 &tm.tm_year, &tm.tm_mon, &tm.tm_mday,
531 &tm.tm_hour, &tm.tm_min, &tm.tm_sec) != 6) {
532 ftp_seterr(FTP_PROTOCOL_ERROR);
533 return (-1);
534 }
535 tm.tm_mon--;
536 tm.tm_year -= 1900;
537 tm.tm_isdst = -1;
538 t = timegm(&tm);
539 if (t == (time_t)-1)
540 t = time(NULL);
541 us->mtime = t;
542 us->atime = t;
543
544 return (0);
545 }
546
547 /*
548 * I/O functions for FTP
549 */
550 struct ftpio {
551 conn_t *cconn; /* Control connection */
552 conn_t *dconn; /* Data connection */
553 int dir; /* Direction */
554 int eof; /* EOF reached */
555 int err; /* Error code */
556 };
557
558 static ssize_t ftp_readfn(void *, void *, size_t);
559 static ssize_t ftp_writefn(void *, const void *, size_t);
560 static void ftp_closefn(void *);
561
562 static ssize_t
ftp_readfn(void * v,void * buf,size_t len)563 ftp_readfn(void *v, void *buf, size_t len)
564 {
565 struct ftpio *io;
566 ssize_t r;
567
568 io = (struct ftpio *)v;
569 if (io == NULL) {
570 errno = EBADF;
571 return (-1);
572 }
573 if (io->cconn == NULL || io->dconn == NULL || io->dir == O_WRONLY) {
574 errno = EBADF;
575 return (-1);
576 }
577 if (io->err) {
578 errno = io->err;
579 return (-1);
580 }
581 if (io->eof)
582 return (0);
583 r = fetch_read(io->dconn, buf, len);
584 if (r > 0)
585 return (r);
586 if (r == 0) {
587 io->eof = 1;
588 return (0);
589 }
590 if (errno != EINTR)
591 io->err = errno;
592 return (-1);
593 }
594
595 static ssize_t
ftp_writefn(void * v,const void * buf,size_t len)596 ftp_writefn(void *v, const void *buf, size_t len)
597 {
598 struct ftpio *io;
599 ssize_t w;
600
601 io = (struct ftpio *)v;
602 if (io == NULL) {
603 errno = EBADF;
604 return (-1);
605 }
606 if (io->cconn == NULL || io->dconn == NULL || io->dir == O_RDONLY) {
607 errno = EBADF;
608 return (-1);
609 }
610 if (io->err) {
611 errno = io->err;
612 return (-1);
613 }
614 w = fetch_write(io->dconn, buf, len);
615 if (w >= 0)
616 return (w);
617 if (errno != EINTR)
618 io->err = errno;
619 return (-1);
620 }
621
622 static int
ftp_disconnect(conn_t * conn)623 ftp_disconnect(conn_t *conn)
624 {
625 ftp_cmd(conn, "QUIT\r\n");
626 return fetch_close(conn);
627 }
628
629 static void
ftp_closefn(void * v)630 ftp_closefn(void *v)
631 {
632 struct ftpio *io;
633
634 io = (struct ftpio *)v;
635 if (io == NULL) {
636 errno = EBADF;
637 return;
638 }
639 if (io->dir == -1)
640 return;
641 if (io->cconn == NULL || io->dconn == NULL) {
642 errno = EBADF;
643 return;
644 }
645 fetch_close(io->dconn);
646 io->dconn = NULL;
647 io->dir = -1;
648 (void)ftp_chkerr(io->cconn);
649 fetch_cache_put(io->cconn, ftp_disconnect);
650 free(io);
651 return;
652 }
653
654 static fetchIO *
ftp_setup(conn_t * cconn,conn_t * dconn,int mode)655 ftp_setup(conn_t *cconn, conn_t *dconn, int mode)
656 {
657 struct ftpio *io;
658 fetchIO *f;
659
660 if (cconn == NULL || dconn == NULL)
661 return (NULL);
662 if ((io = malloc(sizeof(*io))) == NULL)
663 return (NULL);
664 io->cconn = cconn;
665 io->dconn = dconn;
666 io->dir = mode;
667 io->eof = io->err = 0;
668 f = fetchIO_unopen(io, ftp_readfn, ftp_writefn, ftp_closefn);
669 if (f == NULL)
670 free(io);
671 return (f);
672 }
673
674 /*
675 * Transfer file
676 */
677 static fetchIO *
ftp_transfer(conn_t * conn,const char * oper,const char * file,const char * op_arg,int mode,off_t offset,const char * flags)678 ftp_transfer(conn_t *conn, const char *oper, const char *file, const char *op_arg,
679 int mode, off_t offset, const char *flags)
680 {
681 union anonymous {
682 struct sockaddr_storage ss;
683 struct sockaddr sa;
684 struct sockaddr_in6 sin6;
685 struct sockaddr_in sin4;
686 } u;
687 const char *bindaddr;
688 const char *filename;
689 size_t filenamelen;
690 int type;
691 int low, pasv, verbose;
692 int e, sd = -1;
693 socklen_t l;
694 char *s;
695 fetchIO *df;
696
697 /* check flags */
698 low = CHECK_FLAG('l');
699 pasv = !CHECK_FLAG('a');
700 verbose = CHECK_FLAG('v');
701
702 /* passive mode */
703 if (!pasv)
704 pasv = ((s = getenv("FTP_PASSIVE_MODE")) != NULL &&
705 strncasecmp(s, "no", 2) != 0);
706
707 /* isolate filename */
708 filename = ftp_filename(file, &filenamelen, &type, op_arg != NULL);
709
710 /* set transfer mode and data type */
711 if ((e = ftp_mode_type(conn, 0, type)) != FTP_OK)
712 goto ouch;
713
714 /* find our own address, bind, and listen */
715 l = sizeof(u.ss);
716 if (getsockname(conn->sd, &u.sa, &l) == -1)
717 goto sysouch;
718 if (u.ss.ss_family == AF_INET6)
719 unmappedaddr(&u.sin6, &l);
720
721 retry_mode:
722
723 /* open data socket */
724 if ((sd = socket(u.ss.ss_family, SOCK_STREAM, IPPROTO_TCP)) == -1) {
725 fetch_syserr();
726 return (NULL);
727 }
728
729 if (pasv) {
730 unsigned char addr[64];
731 char *ln, *p;
732 unsigned int i;
733 int port;
734
735 /* send PASV command */
736 if (verbose)
737 fetch_info("setting passive mode");
738 switch (u.ss.ss_family) {
739 case AF_INET:
740 if ((e = ftp_cmd(conn, "PASV\r\n")) != FTP_PASSIVE_MODE)
741 goto ouch;
742 break;
743 case AF_INET6:
744 if ((e = ftp_cmd(conn, "EPSV\r\n")) != FTP_EPASSIVE_MODE) {
745 if (e == -1)
746 goto ouch;
747 if ((e = ftp_cmd(conn, "LPSV\r\n")) !=
748 FTP_LPASSIVE_MODE)
749 goto ouch;
750 }
751 break;
752 default:
753 e = FTP_PROTOCOL_ERROR; /* XXX: error code should be prepared */
754 goto ouch;
755 }
756
757 /*
758 * Find address and port number. The reply to the PASV command
759 * is IMHO the one and only weak point in the FTP protocol.
760 */
761 ln = conn->buf;
762 switch (e) {
763 case FTP_PASSIVE_MODE:
764 case FTP_LPASSIVE_MODE:
765 for (p = ln + 3; *p && !isdigit((unsigned char)*p); p++)
766 /* nothing */ ;
767 if (!*p) {
768 e = FTP_PROTOCOL_ERROR;
769 goto ouch;
770 }
771 l = (e == FTP_PASSIVE_MODE ? 6 : 21);
772 for (i = 0; *p && i < l; i++, p++)
773 addr[i] = (unsigned char)strtol(p, &p, 10);
774 if (i < l) {
775 e = FTP_PROTOCOL_ERROR;
776 goto ouch;
777 }
778 break;
779 case FTP_EPASSIVE_MODE:
780 for (p = ln + 3; *p && *p != '('; p++)
781 /* nothing */ ;
782 if (!*p) {
783 e = FTP_PROTOCOL_ERROR;
784 goto ouch;
785 }
786 ++p;
787 if (sscanf(p, "%c%c%c%d%c", &addr[0], &addr[1], &addr[2],
788 &port, &addr[3]) != 5 ||
789 addr[0] != addr[1] ||
790 addr[0] != addr[2] || addr[0] != addr[3]) {
791 e = FTP_PROTOCOL_ERROR;
792 goto ouch;
793 }
794 break;
795 case FTP_SYNTAX_ERROR:
796 if (verbose)
797 fetch_info("passive mode failed");
798 /* Close socket and retry with passive mode. */
799 pasv = 0;
800 close(sd);
801 sd = -1;
802 goto retry_mode;
803 }
804
805 /* seek to required offset */
806 if (offset)
807 if (ftp_cmd(conn, "REST %lu\r\n", (unsigned long)offset) != FTP_FILE_OK)
808 goto sysouch;
809
810 /* construct sockaddr for data socket */
811 l = sizeof(u.ss);
812 if (getpeername(conn->sd, &u.sa, &l) == -1)
813 goto sysouch;
814 if (u.ss.ss_family == AF_INET6)
815 unmappedaddr(&u.sin6, &l);
816 switch (u.ss.ss_family) {
817 case AF_INET6:
818 if (e == FTP_EPASSIVE_MODE)
819 u.sin6.sin6_port = htons(port);
820 else {
821 memcpy(&u.sin6.sin6_addr, addr + 2, 16);
822 memcpy(&u.sin6.sin6_port, addr + 19, 2);
823 }
824 break;
825 case AF_INET:
826 if (e == FTP_EPASSIVE_MODE)
827 u.sin4.sin_port = htons(port);
828 else {
829 memcpy(&u.sin4.sin_addr, addr, 4);
830 memcpy(&u.sin4.sin_port, addr + 4, 2);
831 }
832 break;
833 default:
834 e = FTP_PROTOCOL_ERROR; /* XXX: error code should be prepared */
835 break;
836 }
837
838 /* connect to data port */
839 if (verbose)
840 fetch_info("opening data connection");
841 bindaddr = getenv("FETCH_BIND_ADDRESS");
842 if (bindaddr != NULL && *bindaddr != '\0' &&
843 fetch_bind(sd, u.ss.ss_family, bindaddr) != 0)
844 goto sysouch;
845 if (connect(sd, &u.sa, l) == -1)
846 goto sysouch;
847
848 /* make the server initiate the transfer */
849 if (verbose)
850 fetch_info("initiating transfer");
851 if (op_arg)
852 e = ftp_cmd(conn, "%s%s%s\r\n", oper, *op_arg ? " " : "", op_arg);
853 else
854 e = ftp_cmd(conn, "%s %.*s\r\n", oper,
855 (int)filenamelen, filename);
856 if (e != FTP_CONNECTION_ALREADY_OPEN && e != FTP_OPEN_DATA_CONNECTION)
857 goto ouch;
858
859 } else {
860 uint32_t a;
861 uint16_t p;
862 #if defined(IPV6_PORTRANGE) || defined(IP_PORTRANGE)
863 int arg;
864 #endif
865 int d;
866 char hname[INET6_ADDRSTRLEN];
867
868 switch (u.ss.ss_family) {
869 case AF_INET6:
870 u.sin6.sin6_port = 0;
871 #ifdef IPV6_PORTRANGE
872 arg = low ? IPV6_PORTRANGE_DEFAULT : IPV6_PORTRANGE_HIGH;
873 if (setsockopt(sd, IPPROTO_IPV6, IPV6_PORTRANGE,
874 &arg, (socklen_t)sizeof(arg)) == -1)
875 goto sysouch;
876 #endif
877 break;
878 case AF_INET:
879 u.sin4.sin_port = 0;
880 #ifdef IP_PORTRANGE
881 arg = low ? IP_PORTRANGE_DEFAULT : IP_PORTRANGE_HIGH;
882 if (setsockopt(sd, IPPROTO_IP, IP_PORTRANGE,
883 &arg, (socklen_t)sizeof(arg)) == -1)
884 goto sysouch;
885 #endif
886 break;
887 }
888 if (verbose)
889 fetch_info("binding data socket");
890 if (bind(sd, &u.sa, l) == -1)
891 goto sysouch;
892 if (listen(sd, 1) == -1)
893 goto sysouch;
894
895 /* find what port we're on and tell the server */
896 if (getsockname(sd, &u.sa, &l) == -1)
897 goto sysouch;
898 switch (u.ss.ss_family) {
899 case AF_INET:
900 a = ntohl(u.sin4.sin_addr.s_addr);
901 p = ntohs(u.sin4.sin_port);
902 e = ftp_cmd(conn, "PORT %d,%d,%d,%d,%d,%d\r\n",
903 (a >> 24) & 0xff, (a >> 16) & 0xff,
904 (a >> 8) & 0xff, a & 0xff,
905 ((unsigned int)p >> 8) & 0xff, p & 0xff);
906 break;
907 case AF_INET6:
908 e = -1;
909 u.sin6.sin6_scope_id = 0;
910 if (getnameinfo(&u.sa, l,
911 hname, (socklen_t)sizeof(hname),
912 NULL, 0, NI_NUMERICHOST) == 0) {
913 e = ftp_cmd(conn, "EPRT |%d|%s|%d|\r\n", 2, hname,
914 htons(u.sin6.sin6_port));
915 if (e == -1)
916 goto ouch;
917 }
918 if (e != FTP_OK) {
919 uint8_t aa[sizeof(u.sin6.sin6_addr)];
920 memcpy(aa, &u.sin6.sin6_addr, sizeof(aa));
921 p = ntohs(u.sin6.sin6_port);
922 e = ftp_cmd(conn,
923 "LPRT %d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d\r\n",
924 6, 16,
925 aa[ 0], aa[ 1], aa[ 2], aa[ 3],
926 aa[ 4], aa[ 5], aa[ 6], aa[ 7],
927 aa[ 8], aa[ 9], aa[10], aa[11],
928 aa[12], aa[13], aa[14], aa[15],
929 2,
930 ((unsigned int)p >> 8) & 0xff, p & 0xff);
931 }
932 break;
933 default:
934 e = FTP_PROTOCOL_ERROR; /* XXX: error code should be prepared */
935 goto ouch;
936 }
937 if (e != FTP_OK)
938 goto ouch;
939
940 /* seek to required offset */
941 if (offset)
942 if (ftp_cmd(conn, "REST %llu\r\n", (unsigned long long)offset) != FTP_FILE_OK)
943 goto sysouch;
944
945 /* make the server initiate the transfer */
946 if (verbose)
947 fetch_info("initiating transfer");
948 if (op_arg)
949 e = ftp_cmd(conn, "%s%s%s\r\n", oper, *op_arg ? " " : "", op_arg);
950 else
951 e = ftp_cmd(conn, "%s %.*s\r\n", oper,
952 (int)filenamelen, filename);
953 if (e != FTP_CONNECTION_ALREADY_OPEN && e != FTP_OPEN_DATA_CONNECTION)
954 goto ouch;
955
956 /* accept the incoming connection and go to town */
957 if ((d = accept(sd, NULL, NULL)) == -1)
958 goto sysouch;
959 close(sd);
960 sd = d;
961 }
962
963 if ((df = ftp_setup(conn, fetch_reopen(sd), mode)) == NULL)
964 goto sysouch;
965 return (df);
966
967 sysouch:
968 fetch_syserr();
969 if (sd >= 0)
970 close(sd);
971 return (NULL);
972
973 ouch:
974 if (e != -1)
975 ftp_seterr(e);
976 if (sd >= 0)
977 close(sd);
978 return (NULL);
979 }
980
981 /*
982 * Authenticate
983 */
984 static int
ftp_authenticate(conn_t * conn,struct url * url,struct url * purl)985 ftp_authenticate(conn_t *conn, struct url *url, struct url *purl)
986 {
987 const char *user, *pwd, *login_name;
988 char pbuf[URL_USERLEN + 1 + URL_HOSTLEN + 1];
989 int e, len;
990
991 /* XXX FTP_AUTH, and maybe .netrc */
992
993 /* send user name and password */
994 if (url->user[0] == '\0')
995 fetch_netrc_auth(url);
996 user = url->user;
997 if (*user == '\0')
998 user = getenv("FTP_LOGIN");
999 if (user == NULL || *user == '\0')
1000 user = FTP_ANONYMOUS_USER;
1001 if (purl && url->port == fetch_default_port(url->scheme))
1002 e = ftp_cmd(conn, "USER %s@%s\r\n", user, url->host);
1003 else if (purl)
1004 e = ftp_cmd(conn, "USER %s@%s@%d\r\n", user, url->host, url->port);
1005 else
1006 e = ftp_cmd(conn, "USER %s\r\n", user);
1007
1008 /* did the server request a password? */
1009 if (e == FTP_NEED_PASSWORD) {
1010 pwd = url->pwd;
1011 if (*pwd == '\0')
1012 pwd = getenv("FTP_PASSWORD");
1013 if (pwd == NULL || *pwd == '\0') {
1014 if ((login_name = getlogin()) == 0)
1015 login_name = FTP_ANONYMOUS_USER;
1016 if ((len = snprintf(pbuf, URL_USERLEN + 2, "%s@", login_name)) < 0)
1017 len = 0;
1018 else if (len > URL_USERLEN + 1)
1019 len = URL_USERLEN + 1;
1020 gethostname(pbuf + len, sizeof(pbuf) - len);
1021 /* MAXHOSTNAMELEN can differ from URL_HOSTLEN + 1 */
1022 pbuf[sizeof(pbuf) - 1] = '\0';
1023 pwd = pbuf;
1024 }
1025 e = ftp_cmd(conn, "PASS %s\r\n", pwd);
1026 }
1027
1028 return (e);
1029 }
1030
1031 /*
1032 * Log on to FTP server
1033 */
1034 static conn_t *
ftp_connect(struct url * url,struct url * purl,const char * flags)1035 ftp_connect(struct url *url, struct url *purl, const char *flags)
1036 {
1037 conn_t *conn;
1038 int e, direct, verbose;
1039 #ifdef INET6
1040 int af = AF_UNSPEC;
1041 #else
1042 int af = AF_INET;
1043 #endif
1044
1045 direct = CHECK_FLAG('d');
1046 verbose = CHECK_FLAG('v');
1047 if (CHECK_FLAG('4'))
1048 af = AF_INET;
1049 else if (CHECK_FLAG('6'))
1050 af = AF_INET6;
1051
1052 if (direct)
1053 purl = NULL;
1054
1055 /* check for proxy */
1056 if (purl) {
1057 /* XXX proxy authentication! */
1058 /* XXX connetion caching */
1059 if (!purl->port)
1060 purl->port = fetch_default_port(purl->scheme);
1061
1062 conn = fetch_connect(purl, af, verbose);
1063 } else {
1064 /* no proxy, go straight to target */
1065 if (!url->port)
1066 url->port = fetch_default_port(url->scheme);
1067
1068 while ((conn = fetch_cache_get(url, af)) != NULL) {
1069 e = ftp_cmd(conn, "NOOP\r\n");
1070 if (e == FTP_OK)
1071 return conn;
1072 fetch_close(conn);
1073 }
1074 conn = fetch_connect(url, af, verbose);
1075 purl = NULL;
1076 }
1077
1078 /* check connection */
1079 if (conn == NULL)
1080 /* fetch_connect() has already set an error code */
1081 return (NULL);
1082
1083 /* expect welcome message */
1084 if ((e = ftp_chkerr(conn)) != FTP_SERVICE_READY)
1085 goto fouch;
1086
1087 /* authenticate */
1088 if ((e = ftp_authenticate(conn, url, purl)) != FTP_LOGGED_IN)
1089 goto fouch;
1090
1091 /* TODO: Request extended features supported, if any (RFC 3659). */
1092
1093 /* done */
1094 return (conn);
1095
1096 fouch:
1097 if (e != -1)
1098 ftp_seterr(e);
1099 fetch_close(conn);
1100 return (NULL);
1101 }
1102
1103 /*
1104 * Check the proxy settings
1105 */
1106 static struct url *
ftp_get_proxy(struct url * url,const char * flags)1107 ftp_get_proxy(struct url * url, const char *flags)
1108 {
1109 struct url *purl;
1110 char *p, *fp, *FP, *hp, *HP;
1111
1112 if (flags != NULL && strchr(flags, 'd') != NULL)
1113 return NULL;
1114 if (fetch_no_proxy_match(url->host))
1115 return NULL;
1116
1117 FP = getenv("FTP_PROXY");
1118 fp = getenv("ftp_proxy");
1119 HP = getenv("HTTP_PROXY");
1120 hp = getenv("http_proxy");
1121
1122 if ((((p = FP) || (p = fp) || (p = HP) || (p = hp))) &&
1123 *p && (purl = fetchParseURL(p)) != NULL) {
1124 if (!*purl->scheme) {
1125 if (fp || FP)
1126 strcpy(purl->scheme, SCHEME_FTP);
1127 else
1128 strcpy(purl->scheme, SCHEME_HTTP);
1129 }
1130 if (!purl->port)
1131 purl->port = fetch_default_proxy_port(purl->scheme);
1132 if (strcasecmp(purl->scheme, SCHEME_FTP) == 0 ||
1133 strcasecmp(purl->scheme, SCHEME_HTTP) == 0)
1134 return purl;
1135 fetchFreeURL(purl);
1136 }
1137 return NULL;
1138 }
1139
1140 /*
1141 * Process an FTP request
1142 */
1143 fetchIO *
ftp_request(struct url * url,const char * op,const char * op_arg,struct url_stat * us,struct url * purl,const char * flags)1144 ftp_request(struct url *url, const char *op, const char *op_arg,
1145 struct url_stat *us, struct url *purl, const char *flags)
1146 {
1147 fetchIO *f;
1148 char *path;
1149 conn_t *conn;
1150 int if_modified_since, oflag;
1151 struct url_stat local_us;
1152
1153 /* check if we should use HTTP instead */
1154 if (purl && strcasecmp(purl->scheme, SCHEME_HTTP) == 0) {
1155 if (strcmp(op, "STAT") == 0)
1156 return (http_request(url, "HEAD", us, purl, flags));
1157 else if (strcmp(op, "RETR") == 0)
1158 return (http_request(url, "GET", us, purl, flags));
1159 /*
1160 * Our HTTP code doesn't support PUT requests yet, so try
1161 * a direct connection.
1162 */
1163 }
1164
1165 /* connect to server */
1166 conn = ftp_connect(url, purl, flags);
1167 if (purl)
1168 fetchFreeURL(purl);
1169 if (conn == NULL)
1170 return (NULL);
1171
1172 if ((path = fetchUnquotePath(url)) == NULL) {
1173 fetch_syserr();
1174 return NULL;
1175 }
1176
1177 /* change directory */
1178 if (ftp_cwd(conn, path, op_arg != NULL) == -1) {
1179 free(path);
1180 return (NULL);
1181 }
1182
1183 if_modified_since = CHECK_FLAG('i');
1184 if (if_modified_since && us == NULL)
1185 us = &local_us;
1186
1187 /* stat file */
1188 if (us && ftp_stat(conn, path, us) == -1
1189 && fetchLastErrCode != FETCH_PROTO
1190 && fetchLastErrCode != FETCH_UNAVAIL) {
1191 free(path);
1192 return (NULL);
1193 }
1194
1195 if (if_modified_since && url->last_modified > 0 &&
1196 url->last_modified >= us->mtime) {
1197 free(path);
1198 fetchLastErrCode = FETCH_UNCHANGED;
1199 snprintf(fetchLastErrString, MAXERRSTRING, "Unchanged");
1200 return NULL;
1201 }
1202
1203 /* just a stat */
1204 if (strcmp(op, "STAT") == 0) {
1205 free(path);
1206 return fetchIO_unopen(NULL, NULL, NULL, NULL);
1207 }
1208 if (strcmp(op, "STOR") == 0 || strcmp(op, "APPE") == 0)
1209 oflag = O_WRONLY;
1210 else
1211 oflag = O_RDONLY;
1212
1213 /* initiate the transfer */
1214 f = (ftp_transfer(conn, op, path, op_arg, oflag, url->offset, flags));
1215 free(path);
1216 return f;
1217 }
1218
1219 /*
1220 * Get and stat file
1221 */
1222 fetchIO *
fetchXGetFTP(struct url * url,struct url_stat * us,const char * flags)1223 fetchXGetFTP(struct url *url, struct url_stat *us, const char *flags)
1224 {
1225 return (ftp_request(url, "RETR", NULL, us, ftp_get_proxy(url, flags), flags));
1226 }
1227
1228 /*
1229 * Get file
1230 */
1231 fetchIO *
fetchGetFTP(struct url * url,const char * flags)1232 fetchGetFTP(struct url *url, const char *flags)
1233 {
1234 return (fetchXGetFTP(url, NULL, flags));
1235 }
1236
1237 /*
1238 * Put file
1239 */
1240 fetchIO *
fetchPutFTP(struct url * url,const char * flags)1241 fetchPutFTP(struct url *url, const char *flags)
1242 {
1243 return (ftp_request(url, CHECK_FLAG('a') ? "APPE" : "STOR", NULL, NULL,
1244 ftp_get_proxy(url, flags), flags));
1245 }
1246
1247 /*
1248 * Get file stats
1249 */
1250 int
fetchStatFTP(struct url * url,struct url_stat * us,const char * flags)1251 fetchStatFTP(struct url *url, struct url_stat *us, const char *flags)
1252 {
1253 fetchIO *f;
1254
1255 f = ftp_request(url, "STAT", NULL, us, ftp_get_proxy(url, flags), flags);
1256 if (f == NULL)
1257 return (-1);
1258 fetchIO_close(f);
1259 return (0);
1260 }
1261
1262 /*
1263 * List a directory
1264 */
1265 int
fetchListFTP(struct url_list * ue,struct url * url,const char * pattern,const char * flags)1266 fetchListFTP(struct url_list *ue, struct url *url, const char *pattern, const char *flags)
1267 {
1268 fetchIO *f;
1269 char buf[2 * PATH_MAX], *eol, *eos;
1270 ssize_t len;
1271 size_t cur_off;
1272 int ret;
1273
1274 /* XXX What about proxies? */
1275 if (pattern == NULL || strcmp(pattern, "*") == 0)
1276 pattern = "";
1277 f = ftp_request(url, "NLST", pattern, NULL, ftp_get_proxy(url, flags), flags);
1278 if (f == NULL)
1279 return -1;
1280
1281 cur_off = 0;
1282 ret = 0;
1283
1284 while ((len = fetchIO_read(f, buf + cur_off, sizeof(buf) - cur_off)) > 0) {
1285 cur_off += len;
1286 while ((eol = memchr(buf, '\n', cur_off)) != NULL) {
1287 if (len == eol - buf)
1288 break;
1289 if (eol != buf) {
1290 if (eol[-1] == '\r')
1291 eos = eol - 1;
1292 else
1293 eos = eol;
1294 *eos = '\0';
1295 ret = fetch_add_entry(ue, url, buf, 0);
1296 if (ret)
1297 break;
1298 cur_off -= eol - buf + 1;
1299 memmove(buf, eol + 1, cur_off);
1300 }
1301 }
1302 if (ret)
1303 break;
1304 }
1305 if (cur_off != 0 || len < 0) {
1306 /* Not RFC conform, bail out. */
1307 fetchIO_close(f);
1308 return -1;
1309 }
1310 fetchIO_close(f);
1311 return ret;
1312 }
1313