1 /*-
2 * SPDX-License-Identifier: (BSD-3-Clause AND Beerware)
3 *
4 * Copyright (c) 1998-2011 Dag-Erling Smørgrav
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
31 #include <sys/cdefs.h>
32 /*
33 * Portions of this code were taken from or based on ftpio.c:
34 *
35 * ----------------------------------------------------------------------------
36 * "THE BEER-WARE LICENSE" (Revision 42):
37 * <phk@FreeBSD.org> wrote this file. As long as you retain this notice you
38 * can do whatever you want with this stuff. If we meet some day, and you think
39 * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
40 * ----------------------------------------------------------------------------
41 *
42 * Major Changelog:
43 *
44 * Dag-Erling Smørgrav
45 * 9 Jun 1998
46 *
47 * Incorporated into libfetch
48 *
49 * Jordan K. Hubbard
50 * 17 Jan 1996
51 *
52 * Turned inside out. Now returns xfers as new file ids, not as a special
53 * `state' of FTP_t
54 *
55 * $ftpioId: ftpio.c,v 1.30 1998/04/11 07:28:53 phk Exp $
56 *
57 */
58
59 #include <sys/param.h>
60 #include <sys/socket.h>
61 #include <netinet/in.h>
62
63 #include <ctype.h>
64 #include <err.h>
65 #include <errno.h>
66 #include <fcntl.h>
67 #include <netdb.h>
68 #include <stdarg.h>
69 #include <stdint.h>
70 #include <stdio.h>
71 #include <stdlib.h>
72 #include <string.h>
73 #include <time.h>
74 #include <unistd.h>
75
76 #include "fetch.h"
77 #include "common.h"
78 #include "ftperr.h"
79
80 #define FTP_ANONYMOUS_USER "anonymous"
81
82 #define FTP_CONNECTION_ALREADY_OPEN 125
83 #define FTP_OPEN_DATA_CONNECTION 150
84 #define FTP_OK 200
85 #define FTP_FILE_STATUS 213
86 #define FTP_SERVICE_READY 220
87 #define FTP_TRANSFER_COMPLETE 226
88 #define FTP_PASSIVE_MODE 227
89 #define FTP_LPASSIVE_MODE 228
90 #define FTP_EPASSIVE_MODE 229
91 #define FTP_LOGGED_IN 230
92 #define FTP_FILE_ACTION_OK 250
93 #define FTP_DIRECTORY_CREATED 257 /* multiple meanings */
94 #define FTP_FILE_CREATED 257 /* multiple meanings */
95 #define FTP_WORKING_DIRECTORY 257 /* multiple meanings */
96 #define FTP_NEED_PASSWORD 331
97 #define FTP_NEED_ACCOUNT 332
98 #define FTP_FILE_OK 350
99 #define FTP_SYNTAX_ERROR 500
100 #define FTP_PROTOCOL_ERROR 999
101
102 static struct url cached_host;
103 static conn_t *cached_connection;
104
105 #define isftpreply(foo) \
106 (isdigit((unsigned char)foo[0]) && \
107 isdigit((unsigned char)foo[1]) && \
108 isdigit((unsigned char)foo[2]) && \
109 (foo[3] == ' ' || foo[3] == '\0'))
110 #define isftpinfo(foo) \
111 (isdigit((unsigned char)foo[0]) && \
112 isdigit((unsigned char)foo[1]) && \
113 isdigit((unsigned char)foo[2]) && \
114 foo[3] == '-')
115
116 /*
117 * Translate IPv4 mapped IPv6 address to IPv4 address
118 */
119 static void
unmappedaddr(struct sockaddr_in6 * sin6)120 unmappedaddr(struct sockaddr_in6 *sin6)
121 {
122 struct sockaddr_in *sin4;
123 u_int32_t addr;
124 int port;
125
126 if (sin6->sin6_family != AF_INET6 ||
127 !IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr))
128 return;
129 sin4 = (struct sockaddr_in *)sin6;
130 addr = *(u_int32_t *)(uintptr_t)&sin6->sin6_addr.s6_addr[12];
131 port = sin6->sin6_port;
132 memset(sin4, 0, sizeof(struct sockaddr_in));
133 sin4->sin_addr.s_addr = addr;
134 sin4->sin_port = port;
135 sin4->sin_family = AF_INET;
136 sin4->sin_len = sizeof(struct sockaddr_in);
137 }
138
139 /*
140 * Get server response
141 */
142 static int
ftp_chkerr(conn_t * conn)143 ftp_chkerr(conn_t *conn)
144 {
145 if (fetch_getln(conn) == -1) {
146 fetch_syserr();
147 return (-1);
148 }
149 if (isftpinfo(conn->buf)) {
150 while (conn->buflen && !isftpreply(conn->buf)) {
151 if (fetch_getln(conn) == -1) {
152 fetch_syserr();
153 return (-1);
154 }
155 }
156 }
157
158 while (conn->buflen &&
159 isspace((unsigned char)conn->buf[conn->buflen - 1]))
160 conn->buflen--;
161 conn->buf[conn->buflen] = '\0';
162
163 if (!isftpreply(conn->buf)) {
164 ftp_seterr(FTP_PROTOCOL_ERROR);
165 return (-1);
166 }
167
168 conn->err = (conn->buf[0] - '0') * 100
169 + (conn->buf[1] - '0') * 10
170 + (conn->buf[2] - '0');
171
172 return (conn->err);
173 }
174
175 /*
176 * Send a command and check reply
177 */
178 static int
ftp_cmd(conn_t * conn,const char * fmt,...)179 ftp_cmd(conn_t *conn, const char *fmt, ...)
180 {
181 va_list ap;
182 size_t len;
183 char *msg;
184 int r;
185
186 va_start(ap, fmt);
187 len = vasprintf(&msg, fmt, ap);
188 va_end(ap);
189
190 if (msg == NULL) {
191 errno = ENOMEM;
192 fetch_syserr();
193 return (-1);
194 }
195
196 r = fetch_putln(conn, msg, len);
197 free(msg);
198
199 if (r == -1) {
200 fetch_syserr();
201 return (-1);
202 }
203
204 return (ftp_chkerr(conn));
205 }
206
207 /*
208 * Return a pointer to the filename part of a path
209 */
210 static const char *
ftp_filename(const char * file,int * len,int * type)211 ftp_filename(const char *file, int *len, int *type)
212 {
213 const char *s;
214
215 if ((s = strrchr(file, '/')) == NULL)
216 s = file;
217 else
218 s = s + 1;
219 *len = strlen(s);
220 if (*len > 7 && strncmp(s + *len - 7, ";type=", 6) == 0) {
221 *type = s[*len - 1];
222 *len -= 7;
223 } else {
224 *type = '\0';
225 }
226 return (s);
227 }
228
229 /*
230 * Get current working directory from the reply to a CWD, PWD or CDUP
231 * command.
232 */
233 static int
ftp_pwd(conn_t * conn,char * pwd,size_t pwdlen)234 ftp_pwd(conn_t *conn, char *pwd, size_t pwdlen)
235 {
236 char *src, *dst, *end;
237 int q;
238
239 if (conn->err != FTP_WORKING_DIRECTORY &&
240 conn->err != FTP_FILE_ACTION_OK)
241 return (FTP_PROTOCOL_ERROR);
242 end = conn->buf + conn->buflen;
243 src = conn->buf + 4;
244 if (src >= end || *src++ != '"')
245 return (FTP_PROTOCOL_ERROR);
246 for (q = 0, dst = pwd; src < end && pwdlen--; ++src) {
247 if (!q && *src == '"')
248 q = 1;
249 else if (q && *src != '"')
250 break;
251 else if (q)
252 *dst++ = '"', q = 0;
253 else
254 *dst++ = *src;
255 }
256 if (!pwdlen)
257 return (FTP_PROTOCOL_ERROR);
258 *dst = '\0';
259 #if 0
260 DEBUGF("pwd: [%s]\n", pwd);
261 #endif
262 return (FTP_OK);
263 }
264
265 /*
266 * Change working directory to the directory that contains the specified
267 * file.
268 */
269 static int
ftp_cwd(conn_t * conn,const char * file)270 ftp_cwd(conn_t *conn, const char *file)
271 {
272 const char *beg, *end;
273 char pwd[PATH_MAX];
274 int e, i, len;
275
276 /* If no slashes in name, no need to change dirs. */
277 if ((end = strrchr(file, '/')) == NULL)
278 return (0);
279 if ((e = ftp_cmd(conn, "PWD")) != FTP_WORKING_DIRECTORY ||
280 (e = ftp_pwd(conn, pwd, sizeof(pwd))) != FTP_OK) {
281 ftp_seterr(e);
282 return (-1);
283 }
284 for (;;) {
285 len = strlen(pwd);
286
287 /* Look for a common prefix between PWD and dir to fetch. */
288 for (i = 0; i <= len && i <= end - file; ++i)
289 if (pwd[i] != file[i])
290 break;
291 #if 0
292 DEBUGF("have: [%.*s|%s]\n", i, pwd, pwd + i);
293 DEBUGF("want: [%.*s|%s]\n", i, file, file + i);
294 #endif
295 /* Keep going up a dir until we have a matching prefix. */
296 if (pwd[i] == '\0' && (file[i - 1] == '/' || file[i] == '/'))
297 break;
298 if ((e = ftp_cmd(conn, "CDUP")) != FTP_FILE_ACTION_OK ||
299 (e = ftp_cmd(conn, "PWD")) != FTP_WORKING_DIRECTORY ||
300 (e = ftp_pwd(conn, pwd, sizeof(pwd))) != FTP_OK) {
301 ftp_seterr(e);
302 return (-1);
303 }
304 }
305
306 #ifdef FTP_COMBINE_CWDS
307 /* Skip leading slashes, even "////". */
308 for (beg = file + i; beg < end && *beg == '/'; ++beg, ++i)
309 /* nothing */ ;
310
311 /* If there is no trailing dir, we're already there. */
312 if (beg >= end)
313 return (0);
314
315 /* Change to the directory all in one chunk (e.g., foo/bar/baz). */
316 e = ftp_cmd(conn, "CWD %.*s", (int)(end - beg), beg);
317 if (e == FTP_FILE_ACTION_OK)
318 return (0);
319 #endif /* FTP_COMBINE_CWDS */
320
321 /* That didn't work so go back to legacy behavior (multiple CWDs). */
322 for (beg = file + i; beg < end; beg = file + i + 1) {
323 while (*beg == '/')
324 ++beg, ++i;
325 for (++i; file + i < end && file[i] != '/'; ++i)
326 /* nothing */ ;
327 e = ftp_cmd(conn, "CWD %.*s", file + i - beg, beg);
328 if (e != FTP_FILE_ACTION_OK) {
329 ftp_seterr(e);
330 return (-1);
331 }
332 }
333 return (0);
334 }
335
336 /*
337 * Set transfer mode and data type
338 */
339 static int
ftp_mode_type(conn_t * conn,int mode,int type)340 ftp_mode_type(conn_t *conn, int mode, int type)
341 {
342 int e;
343
344 switch (mode) {
345 case 0:
346 case 's':
347 mode = 'S';
348 case 'S':
349 break;
350 default:
351 return (FTP_PROTOCOL_ERROR);
352 }
353 if ((e = ftp_cmd(conn, "MODE %c", mode)) != FTP_OK) {
354 if (mode == 'S') {
355 /*
356 * Stream mode is supposed to be the default - so
357 * much so that some servers not only do not
358 * support any other mode, but do not support the
359 * MODE command at all.
360 *
361 * If "MODE S" fails, it is unlikely that we
362 * previously succeeded in setting a different
363 * mode. Therefore, we simply hope that the
364 * server is already in the correct mode, and
365 * silently ignore the failure.
366 */
367 } else {
368 return (e);
369 }
370 }
371
372 switch (type) {
373 case 0:
374 case 'i':
375 type = 'I';
376 case 'I':
377 break;
378 case 'a':
379 type = 'A';
380 case 'A':
381 break;
382 case 'd':
383 type = 'D';
384 case 'D':
385 /* can't handle yet */
386 default:
387 return (FTP_PROTOCOL_ERROR);
388 }
389 if ((e = ftp_cmd(conn, "TYPE %c", type)) != FTP_OK)
390 return (e);
391
392 return (FTP_OK);
393 }
394
395 /*
396 * Request and parse file stats
397 */
398 static int
ftp_stat(conn_t * conn,const char * file,struct url_stat * us)399 ftp_stat(conn_t *conn, const char *file, struct url_stat *us)
400 {
401 char *ln;
402 const char *filename;
403 int filenamelen, type;
404 struct tm tm;
405 time_t t;
406 int e;
407
408 us->size = -1;
409 us->atime = us->mtime = 0;
410
411 filename = ftp_filename(file, &filenamelen, &type);
412
413 if ((e = ftp_mode_type(conn, 0, type)) != FTP_OK) {
414 ftp_seterr(e);
415 return (-1);
416 }
417
418 e = ftp_cmd(conn, "SIZE %.*s", filenamelen, filename);
419 if (e != FTP_FILE_STATUS) {
420 ftp_seterr(e);
421 return (-1);
422 }
423 for (ln = conn->buf + 4; *ln && isspace((unsigned char)*ln); ln++)
424 /* nothing */ ;
425 for (us->size = 0; *ln && isdigit((unsigned char)*ln); ln++)
426 us->size = us->size * 10 + *ln - '0';
427 if (*ln && !isspace((unsigned char)*ln)) {
428 ftp_seterr(FTP_PROTOCOL_ERROR);
429 us->size = -1;
430 return (-1);
431 }
432 if (us->size == 0)
433 us->size = -1;
434 DEBUGF("size: [%lld]\n", (long long)us->size);
435
436 e = ftp_cmd(conn, "MDTM %.*s", filenamelen, filename);
437 if (e != FTP_FILE_STATUS) {
438 ftp_seterr(e);
439 return (-1);
440 }
441 for (ln = conn->buf + 4; *ln && isspace((unsigned char)*ln); ln++)
442 /* nothing */ ;
443 switch (strspn(ln, "0123456789")) {
444 case 14:
445 break;
446 case 15:
447 ln++;
448 ln[0] = '2';
449 ln[1] = '0';
450 break;
451 default:
452 ftp_seterr(FTP_PROTOCOL_ERROR);
453 return (-1);
454 }
455 if (sscanf(ln, "%04d%02d%02d%02d%02d%02d",
456 &tm.tm_year, &tm.tm_mon, &tm.tm_mday,
457 &tm.tm_hour, &tm.tm_min, &tm.tm_sec) != 6) {
458 ftp_seterr(FTP_PROTOCOL_ERROR);
459 return (-1);
460 }
461 tm.tm_mon--;
462 tm.tm_year -= 1900;
463 tm.tm_isdst = -1;
464 t = timegm(&tm);
465 if (t == (time_t)-1)
466 t = time(NULL);
467 us->mtime = t;
468 us->atime = t;
469 DEBUGF("last modified: [%04d-%02d-%02d %02d:%02d:%02d]\n",
470 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday,
471 tm.tm_hour, tm.tm_min, tm.tm_sec);
472 return (0);
473 }
474
475 /*
476 * I/O functions for FTP
477 */
478 struct ftpio {
479 conn_t *cconn; /* Control connection */
480 conn_t *dconn; /* Data connection */
481 int dir; /* Direction */
482 int eof; /* EOF reached */
483 int err; /* Error code */
484 };
485
486 static int ftp_readfn(void *, char *, int);
487 static int ftp_writefn(void *, const char *, int);
488 static fpos_t ftp_seekfn(void *, fpos_t, int);
489 static int ftp_closefn(void *);
490
491 static int
ftp_readfn(void * v,char * buf,int len)492 ftp_readfn(void *v, char *buf, int len)
493 {
494 struct ftpio *io;
495 int r;
496
497 io = (struct ftpio *)v;
498 if (io == NULL) {
499 errno = EBADF;
500 return (-1);
501 }
502 if (io->cconn == NULL || io->dconn == NULL || io->dir == O_WRONLY) {
503 errno = EBADF;
504 return (-1);
505 }
506 if (io->err) {
507 errno = io->err;
508 return (-1);
509 }
510 if (io->eof)
511 return (0);
512 r = fetch_read(io->dconn, buf, len);
513 if (r > 0)
514 return (r);
515 if (r == 0) {
516 io->eof = 1;
517 return (0);
518 }
519 if (errno != EINTR)
520 io->err = errno;
521 return (-1);
522 }
523
524 static int
ftp_writefn(void * v,const char * buf,int len)525 ftp_writefn(void *v, const char *buf, int len)
526 {
527 struct ftpio *io;
528 int w;
529
530 io = (struct ftpio *)v;
531 if (io == NULL) {
532 errno = EBADF;
533 return (-1);
534 }
535 if (io->cconn == NULL || io->dconn == NULL || io->dir == O_RDONLY) {
536 errno = EBADF;
537 return (-1);
538 }
539 if (io->err) {
540 errno = io->err;
541 return (-1);
542 }
543 w = fetch_write(io->dconn, buf, len);
544 if (w >= 0)
545 return (w);
546 if (errno != EINTR)
547 io->err = errno;
548 return (-1);
549 }
550
551 static fpos_t
ftp_seekfn(void * v,fpos_t pos __unused,int whence __unused)552 ftp_seekfn(void *v, fpos_t pos __unused, int whence __unused)
553 {
554 struct ftpio *io;
555
556 io = (struct ftpio *)v;
557 if (io == NULL) {
558 errno = EBADF;
559 return (-1);
560 }
561 errno = ESPIPE;
562 return (-1);
563 }
564
565 static int
ftp_closefn(void * v)566 ftp_closefn(void *v)
567 {
568 struct ftpio *io;
569 int r;
570
571 io = (struct ftpio *)v;
572 if (io == NULL) {
573 errno = EBADF;
574 return (-1);
575 }
576 if (io->dir == -1)
577 return (0);
578 if (io->cconn == NULL || io->dconn == NULL) {
579 errno = EBADF;
580 return (-1);
581 }
582 fetch_close(io->dconn);
583 io->dir = -1;
584 io->dconn = NULL;
585 DEBUGF("Waiting for final status\n");
586 r = ftp_chkerr(io->cconn);
587 if (io->cconn == cached_connection && io->cconn->ref == 1)
588 cached_connection = NULL;
589 fetch_close(io->cconn);
590 free(io);
591 return (r == FTP_TRANSFER_COMPLETE) ? 0 : -1;
592 }
593
594 static FILE *
ftp_setup(conn_t * cconn,conn_t * dconn,int mode)595 ftp_setup(conn_t *cconn, conn_t *dconn, int mode)
596 {
597 struct ftpio *io;
598 FILE *f;
599
600 if (cconn == NULL || dconn == NULL)
601 return (NULL);
602 if ((io = malloc(sizeof(*io))) == NULL)
603 return (NULL);
604 io->cconn = cconn;
605 io->dconn = dconn;
606 io->dir = mode;
607 io->eof = io->err = 0;
608 f = funopen(io, ftp_readfn, ftp_writefn, ftp_seekfn, ftp_closefn);
609 if (f == NULL)
610 free(io);
611 return (f);
612 }
613
614 /*
615 * Transfer file
616 */
617 static FILE *
ftp_transfer(conn_t * conn,const char * oper,const char * file,int mode,off_t offset,const char * flags)618 ftp_transfer(conn_t *conn, const char *oper, const char *file,
619 int mode, off_t offset, const char *flags)
620 {
621 struct sockaddr_storage sa;
622 struct sockaddr_in6 *sin6;
623 struct sockaddr_in *sin4;
624 const char *bindaddr;
625 const char *filename;
626 int filenamelen, type;
627 int low, pasv, verbose;
628 int e, sd = -1;
629 socklen_t l;
630 char *s;
631 FILE *df;
632
633 /* check flags */
634 low = CHECK_FLAG('l');
635 pasv = CHECK_FLAG('p') || !CHECK_FLAG('P');
636 verbose = CHECK_FLAG('v');
637
638 /* passive mode */
639 if ((s = getenv("FTP_PASSIVE_MODE")) != NULL)
640 pasv = (strncasecmp(s, "no", 2) != 0);
641
642 /* isolate filename */
643 filename = ftp_filename(file, &filenamelen, &type);
644
645 /* set transfer mode and data type */
646 if ((e = ftp_mode_type(conn, 0, type)) != FTP_OK)
647 goto ouch;
648
649 /* find our own address, bind, and listen */
650 l = sizeof(sa);
651 if (getsockname(conn->sd, (struct sockaddr *)&sa, &l) == -1)
652 goto sysouch;
653 if (sa.ss_family == AF_INET6)
654 unmappedaddr((struct sockaddr_in6 *)&sa);
655
656 /* open data socket */
657 if ((sd = socket(sa.ss_family, SOCK_STREAM, IPPROTO_TCP)) == -1) {
658 fetch_syserr();
659 return (NULL);
660 }
661
662 if (pasv) {
663 u_char addr[64];
664 char *ln, *p;
665 unsigned int i;
666 int port;
667
668 /* send PASV command */
669 if (verbose)
670 fetch_info("setting passive mode");
671 switch (sa.ss_family) {
672 case AF_INET:
673 if ((e = ftp_cmd(conn, "PASV")) != FTP_PASSIVE_MODE)
674 goto ouch;
675 break;
676 case AF_INET6:
677 if ((e = ftp_cmd(conn, "EPSV")) != FTP_EPASSIVE_MODE) {
678 if (e == -1)
679 goto ouch;
680 if ((e = ftp_cmd(conn, "LPSV")) !=
681 FTP_LPASSIVE_MODE)
682 goto ouch;
683 }
684 break;
685 default:
686 e = FTP_PROTOCOL_ERROR; /* XXX: error code should be prepared */
687 goto ouch;
688 }
689
690 /*
691 * Find address and port number. The reply to the PASV command
692 * is IMHO the one and only weak point in the FTP protocol.
693 */
694 ln = conn->buf;
695 switch (e) {
696 case FTP_PASSIVE_MODE:
697 case FTP_LPASSIVE_MODE:
698 for (p = ln + 3; *p && !isdigit((unsigned char)*p); p++)
699 /* nothing */ ;
700 if (!*p) {
701 e = FTP_PROTOCOL_ERROR;
702 goto ouch;
703 }
704 l = (e == FTP_PASSIVE_MODE ? 6 : 21);
705 for (i = 0; *p && i < l; i++, p++) {
706 addr[i] = strtol(p, &p, 10);
707 if (*p == '\0' && i < l - 1)
708 break;
709 }
710 if (i < l) {
711 e = FTP_PROTOCOL_ERROR;
712 goto ouch;
713 }
714 break;
715 case FTP_EPASSIVE_MODE:
716 for (p = ln + 3; *p && *p != '('; p++)
717 /* nothing */ ;
718 if (!*p) {
719 e = FTP_PROTOCOL_ERROR;
720 goto ouch;
721 }
722 ++p;
723 if (sscanf(p, "%c%c%c%d%c", &addr[0], &addr[1], &addr[2],
724 &port, &addr[3]) != 5 ||
725 addr[0] != addr[1] ||
726 addr[0] != addr[2] || addr[0] != addr[3]) {
727 e = FTP_PROTOCOL_ERROR;
728 goto ouch;
729 }
730 break;
731 }
732
733 /* seek to required offset */
734 if (offset)
735 if (ftp_cmd(conn, "REST %lu", (u_long)offset) != FTP_FILE_OK)
736 goto sysouch;
737
738 /* construct sockaddr for data socket */
739 l = sizeof(sa);
740 if (getpeername(conn->sd, (struct sockaddr *)&sa, &l) == -1)
741 goto sysouch;
742 if (sa.ss_family == AF_INET6)
743 unmappedaddr((struct sockaddr_in6 *)&sa);
744 switch (sa.ss_family) {
745 case AF_INET6:
746 sin6 = (struct sockaddr_in6 *)&sa;
747 if (e == FTP_EPASSIVE_MODE)
748 sin6->sin6_port = htons(port);
749 else {
750 memcpy(&sin6->sin6_addr, addr + 2, 16);
751 memcpy(&sin6->sin6_port, addr + 19, 2);
752 }
753 break;
754 case AF_INET:
755 sin4 = (struct sockaddr_in *)&sa;
756 if (e == FTP_EPASSIVE_MODE)
757 sin4->sin_port = htons(port);
758 else {
759 memcpy(&sin4->sin_addr, addr, 4);
760 memcpy(&sin4->sin_port, addr + 4, 2);
761 }
762 break;
763 default:
764 e = FTP_PROTOCOL_ERROR; /* XXX: error code should be prepared */
765 break;
766 }
767
768 /* connect to data port */
769 if (verbose)
770 fetch_info("opening data connection");
771 bindaddr = getenv("FETCH_BIND_ADDRESS");
772 if (bindaddr != NULL && *bindaddr != '\0' &&
773 (e = fetch_bind(sd, sa.ss_family, bindaddr)) != 0)
774 goto ouch;
775 if (connect(sd, (struct sockaddr *)&sa, sa.ss_len) == -1)
776 goto sysouch;
777
778 /* make the server initiate the transfer */
779 if (verbose)
780 fetch_info("initiating transfer");
781 e = ftp_cmd(conn, "%s %.*s", oper, filenamelen, filename);
782 if (e != FTP_CONNECTION_ALREADY_OPEN && e != FTP_OPEN_DATA_CONNECTION)
783 goto ouch;
784
785 } else {
786 u_int32_t a;
787 u_short p;
788 int arg, d;
789 char *ap;
790 char hname[INET6_ADDRSTRLEN];
791
792 switch (sa.ss_family) {
793 case AF_INET6:
794 ((struct sockaddr_in6 *)&sa)->sin6_port = 0;
795 #ifdef IPV6_PORTRANGE
796 arg = low ? IPV6_PORTRANGE_DEFAULT : IPV6_PORTRANGE_HIGH;
797 if (setsockopt(sd, IPPROTO_IPV6, IPV6_PORTRANGE,
798 (char *)&arg, sizeof(arg)) == -1)
799 goto sysouch;
800 #endif
801 break;
802 case AF_INET:
803 ((struct sockaddr_in *)&sa)->sin_port = 0;
804 arg = low ? IP_PORTRANGE_DEFAULT : IP_PORTRANGE_HIGH;
805 if (setsockopt(sd, IPPROTO_IP, IP_PORTRANGE,
806 (char *)&arg, sizeof(arg)) == -1)
807 goto sysouch;
808 break;
809 }
810 if (verbose)
811 fetch_info("binding data socket");
812 if (bind(sd, (struct sockaddr *)&sa, sa.ss_len) == -1)
813 goto sysouch;
814 if (listen(sd, 1) == -1)
815 goto sysouch;
816
817 /* find what port we're on and tell the server */
818 if (getsockname(sd, (struct sockaddr *)&sa, &l) == -1)
819 goto sysouch;
820 switch (sa.ss_family) {
821 case AF_INET:
822 sin4 = (struct sockaddr_in *)&sa;
823 a = ntohl(sin4->sin_addr.s_addr);
824 p = ntohs(sin4->sin_port);
825 e = ftp_cmd(conn, "PORT %d,%d,%d,%d,%d,%d",
826 (a >> 24) & 0xff, (a >> 16) & 0xff,
827 (a >> 8) & 0xff, a & 0xff,
828 (p >> 8) & 0xff, p & 0xff);
829 break;
830 case AF_INET6:
831 #define UC(b) (((int)b)&0xff)
832 e = -1;
833 sin6 = (struct sockaddr_in6 *)&sa;
834 sin6->sin6_scope_id = 0;
835 if (getnameinfo((struct sockaddr *)&sa, sa.ss_len,
836 hname, sizeof(hname),
837 NULL, 0, NI_NUMERICHOST) == 0) {
838 e = ftp_cmd(conn, "EPRT |%d|%s|%d|", 2, hname,
839 htons(sin6->sin6_port));
840 if (e == -1)
841 goto ouch;
842 }
843 if (e != FTP_OK) {
844 ap = (char *)&sin6->sin6_addr;
845 e = ftp_cmd(conn,
846 "LPRT %d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d",
847 6, 16,
848 UC(ap[0]), UC(ap[1]), UC(ap[2]), UC(ap[3]),
849 UC(ap[4]), UC(ap[5]), UC(ap[6]), UC(ap[7]),
850 UC(ap[8]), UC(ap[9]), UC(ap[10]), UC(ap[11]),
851 UC(ap[12]), UC(ap[13]), UC(ap[14]), UC(ap[15]),
852 2,
853 (ntohs(sin6->sin6_port) >> 8) & 0xff,
854 ntohs(sin6->sin6_port) & 0xff);
855 }
856 break;
857 default:
858 e = FTP_PROTOCOL_ERROR; /* XXX: error code should be prepared */
859 goto ouch;
860 }
861 if (e != FTP_OK)
862 goto ouch;
863
864 /* seek to required offset */
865 if (offset)
866 if (ftp_cmd(conn, "REST %ju", (uintmax_t)offset) != FTP_FILE_OK)
867 goto sysouch;
868
869 /* make the server initiate the transfer */
870 if (verbose)
871 fetch_info("initiating transfer");
872 e = ftp_cmd(conn, "%s %.*s", oper, filenamelen, filename);
873 if (e != FTP_CONNECTION_ALREADY_OPEN && e != FTP_OPEN_DATA_CONNECTION)
874 goto ouch;
875
876 /* accept the incoming connection and go to town */
877 if ((d = accept(sd, NULL, NULL)) == -1)
878 goto sysouch;
879 close(sd);
880 sd = d;
881 }
882
883 if ((df = ftp_setup(conn, fetch_reopen(sd), mode)) == NULL)
884 goto sysouch;
885 return (df);
886
887 sysouch:
888 fetch_syserr();
889 if (sd >= 0)
890 close(sd);
891 return (NULL);
892
893 ouch:
894 if (e != -1)
895 ftp_seterr(e);
896 if (sd >= 0)
897 close(sd);
898 return (NULL);
899 }
900
901 /*
902 * Authenticate
903 */
904 static int
ftp_authenticate(conn_t * conn,struct url * url,struct url * purl)905 ftp_authenticate(conn_t *conn, struct url *url, struct url *purl)
906 {
907 const char *user, *pwd, *logname;
908 char pbuf[MAXHOSTNAMELEN + MAXLOGNAME + 1];
909 int e, len;
910
911 /* XXX FTP_AUTH, and maybe .netrc */
912
913 /* send user name and password */
914 if (url->user[0] == '\0')
915 fetch_netrc_auth(url);
916 user = url->user;
917 if (*user == '\0')
918 if ((user = getenv("FTP_LOGIN")) != NULL)
919 DEBUGF("FTP_LOGIN=%s\n", user);
920 if (user == NULL || *user == '\0')
921 user = FTP_ANONYMOUS_USER;
922 if (purl && url->port == fetch_default_port(url->scheme))
923 e = ftp_cmd(conn, "USER %s@%s", user, url->host);
924 else if (purl)
925 e = ftp_cmd(conn, "USER %s@%s@%d", user, url->host, url->port);
926 else
927 e = ftp_cmd(conn, "USER %s", user);
928
929 /* did the server request a password? */
930 if (e == FTP_NEED_PASSWORD) {
931 pwd = url->pwd;
932 if (*pwd == '\0')
933 if ((pwd = getenv("FTP_PASSWORD")) != NULL)
934 DEBUGF("FTP_PASSWORD=%s\n", pwd);
935 if (pwd == NULL || *pwd == '\0') {
936 if ((logname = getlogin()) == NULL)
937 logname = FTP_ANONYMOUS_USER;
938 if ((len = snprintf(pbuf, MAXLOGNAME + 1, "%s@", logname)) < 0)
939 len = 0;
940 else if (len > MAXLOGNAME)
941 len = MAXLOGNAME;
942 gethostname(pbuf + len, sizeof(pbuf) - len);
943 pwd = pbuf;
944 }
945 e = ftp_cmd(conn, "PASS %s", pwd);
946 }
947
948 return (e);
949 }
950
951 /*
952 * Log on to FTP server
953 */
954 static conn_t *
ftp_connect(struct url * url,struct url * purl,const char * flags)955 ftp_connect(struct url *url, struct url *purl, const char *flags)
956 {
957 conn_t *conn;
958 int e, direct, verbose;
959 #ifdef INET6
960 int af = AF_UNSPEC;
961 #else
962 int af = AF_INET;
963 #endif
964
965 direct = CHECK_FLAG('d');
966 verbose = CHECK_FLAG('v');
967 if (CHECK_FLAG('4'))
968 af = AF_INET;
969 else if (CHECK_FLAG('6'))
970 af = AF_INET6;
971
972 if (direct)
973 purl = NULL;
974
975 /* check for proxy */
976 if (purl) {
977 /* XXX proxy authentication! */
978 conn = fetch_connect(purl->host, purl->port, af, verbose);
979 } else {
980 /* no proxy, go straight to target */
981 conn = fetch_connect(url->host, url->port, af, verbose);
982 purl = NULL;
983 }
984
985 /* check connection */
986 if (conn == NULL)
987 /* fetch_connect() has already set an error code */
988 return (NULL);
989
990 /* expect welcome message */
991 if ((e = ftp_chkerr(conn)) != FTP_SERVICE_READY)
992 goto fouch;
993
994 /* authenticate */
995 if ((e = ftp_authenticate(conn, url, purl)) != FTP_LOGGED_IN)
996 goto fouch;
997
998 /* TODO: Request extended features supported, if any (RFC 3659). */
999
1000 /* done */
1001 return (conn);
1002
1003 fouch:
1004 if (e != -1)
1005 ftp_seterr(e);
1006 fetch_close(conn);
1007 return (NULL);
1008 }
1009
1010 /*
1011 * Disconnect from server
1012 */
1013 static void
ftp_disconnect(conn_t * conn)1014 ftp_disconnect(conn_t *conn)
1015 {
1016 (void)ftp_cmd(conn, "QUIT");
1017 if (conn == cached_connection && conn->ref == 1)
1018 cached_connection = NULL;
1019 fetch_close(conn);
1020 }
1021
1022 /*
1023 * Check if we're already connected
1024 */
1025 static int
ftp_isconnected(struct url * url)1026 ftp_isconnected(struct url *url)
1027 {
1028 return (cached_connection
1029 && (strcmp(url->host, cached_host.host) == 0)
1030 && (strcmp(url->user, cached_host.user) == 0)
1031 && (strcmp(url->pwd, cached_host.pwd) == 0)
1032 && (url->port == cached_host.port));
1033 }
1034
1035 /*
1036 * Check the cache, reconnect if no luck
1037 */
1038 static conn_t *
ftp_cached_connect(struct url * url,struct url * purl,const char * flags)1039 ftp_cached_connect(struct url *url, struct url *purl, const char *flags)
1040 {
1041 conn_t *conn;
1042 int e;
1043
1044 /* set default port */
1045 if (!url->port)
1046 url->port = fetch_default_port(url->scheme);
1047
1048 /* try to use previously cached connection */
1049 if (ftp_isconnected(url)) {
1050 e = ftp_cmd(cached_connection, "NOOP");
1051 if (e == FTP_OK || e == FTP_SYNTAX_ERROR)
1052 return (fetch_ref(cached_connection));
1053 }
1054
1055 /* connect to server */
1056 if ((conn = ftp_connect(url, purl, flags)) == NULL)
1057 return (NULL);
1058 if (cached_connection)
1059 ftp_disconnect(cached_connection);
1060 cached_connection = fetch_ref(conn);
1061 memcpy(&cached_host, url, sizeof(*url));
1062 return (conn);
1063 }
1064
1065 /*
1066 * Check the proxy settings
1067 */
1068 static struct url *
ftp_get_proxy(struct url * url,const char * flags)1069 ftp_get_proxy(struct url * url, const char *flags)
1070 {
1071 struct url *purl;
1072 char *p;
1073
1074 if (flags != NULL && strchr(flags, 'd') != NULL)
1075 return (NULL);
1076 if (fetch_no_proxy_match(url->host))
1077 return (NULL);
1078 if (((p = getenv("FTP_PROXY")) || (p = getenv("ftp_proxy")) ||
1079 (p = getenv("HTTP_PROXY")) || (p = getenv("http_proxy"))) &&
1080 *p && (purl = fetchParseURL(p)) != NULL) {
1081 if (!*purl->scheme) {
1082 if (getenv("FTP_PROXY") || getenv("ftp_proxy"))
1083 strcpy(purl->scheme, SCHEME_FTP);
1084 else
1085 strcpy(purl->scheme, SCHEME_HTTP);
1086 }
1087 if (!purl->port)
1088 purl->port = fetch_default_proxy_port(purl->scheme);
1089 if (strcmp(purl->scheme, SCHEME_FTP) == 0 ||
1090 strcmp(purl->scheme, SCHEME_HTTP) == 0)
1091 return (purl);
1092 fetchFreeURL(purl);
1093 }
1094 return (NULL);
1095 }
1096
1097 /*
1098 * Process an FTP request
1099 */
1100 FILE *
ftp_request(struct url * url,const char * op,struct url_stat * us,struct url * purl,const char * flags)1101 ftp_request(struct url *url, const char *op, struct url_stat *us,
1102 struct url *purl, const char *flags)
1103 {
1104 conn_t *conn;
1105 int oflag;
1106
1107 /* check if we should use HTTP instead */
1108 if (purl && (strcmp(purl->scheme, SCHEME_HTTP) == 0 ||
1109 strcmp(purl->scheme, SCHEME_HTTPS) == 0)) {
1110 if (strcmp(op, "STAT") == 0)
1111 return (http_request(url, "HEAD", us, purl, flags));
1112 else if (strcmp(op, "RETR") == 0)
1113 return (http_request(url, "GET", us, purl, flags));
1114 /*
1115 * Our HTTP code doesn't support PUT requests yet, so try
1116 * a direct connection.
1117 */
1118 }
1119
1120 /* connect to server */
1121 conn = ftp_cached_connect(url, purl, flags);
1122 if (purl)
1123 fetchFreeURL(purl);
1124 if (conn == NULL)
1125 return (NULL);
1126
1127 /* change directory */
1128 if (ftp_cwd(conn, url->doc) == -1)
1129 goto errsock;
1130
1131 /* stat file */
1132 if (us && ftp_stat(conn, url->doc, us) == -1
1133 && fetchLastErrCode != FETCH_PROTO
1134 && fetchLastErrCode != FETCH_UNAVAIL)
1135 goto errsock;
1136
1137 /* just a stat */
1138 if (strcmp(op, "STAT") == 0) {
1139 --conn->ref;
1140 ftp_disconnect(conn);
1141 return (FILE *)1; /* bogus return value */
1142 }
1143 if (strcmp(op, "STOR") == 0 || strcmp(op, "APPE") == 0)
1144 oflag = O_WRONLY;
1145 else
1146 oflag = O_RDONLY;
1147
1148 /* initiate the transfer */
1149 return (ftp_transfer(conn, op, url->doc, oflag, url->offset, flags));
1150
1151 errsock:
1152 ftp_disconnect(conn);
1153 return (NULL);
1154 }
1155
1156 /*
1157 * Get and stat file
1158 */
1159 FILE *
fetchXGetFTP(struct url * url,struct url_stat * us,const char * flags)1160 fetchXGetFTP(struct url *url, struct url_stat *us, const char *flags)
1161 {
1162 return (ftp_request(url, "RETR", us, ftp_get_proxy(url, flags), flags));
1163 }
1164
1165 /*
1166 * Get file
1167 */
1168 FILE *
fetchGetFTP(struct url * url,const char * flags)1169 fetchGetFTP(struct url *url, const char *flags)
1170 {
1171 return (fetchXGetFTP(url, NULL, flags));
1172 }
1173
1174 /*
1175 * Put file
1176 */
1177 FILE *
fetchPutFTP(struct url * url,const char * flags)1178 fetchPutFTP(struct url *url, const char *flags)
1179 {
1180 return (ftp_request(url, CHECK_FLAG('a') ? "APPE" : "STOR", NULL,
1181 ftp_get_proxy(url, flags), flags));
1182 }
1183
1184 /*
1185 * Get file stats
1186 */
1187 int
fetchStatFTP(struct url * url,struct url_stat * us,const char * flags)1188 fetchStatFTP(struct url *url, struct url_stat *us, const char *flags)
1189 {
1190 FILE *f;
1191
1192 f = ftp_request(url, "STAT", us, ftp_get_proxy(url, flags), flags);
1193 if (f == NULL)
1194 return (-1);
1195 /*
1196 * When op is "STAT", ftp_request() will return either NULL or
1197 * (FILE *)1, never a valid FILE *, so we mustn't fclose(f) before
1198 * returning, as it would cause a segfault.
1199 */
1200 return (0);
1201 }
1202
1203 /*
1204 * List a directory
1205 */
1206 struct url_ent *
fetchListFTP(struct url * url __unused,const char * flags __unused)1207 fetchListFTP(struct url *url __unused, const char *flags __unused)
1208 {
1209 warnx("fetchListFTP(): not implemented");
1210 return (NULL);
1211 }
1212