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 __FBSDID("$FreeBSD$");
33
34 /*
35 * Portions of this code were taken from or based on ftpio.c:
36 *
37 * ----------------------------------------------------------------------------
38 * "THE BEER-WARE LICENSE" (Revision 42):
39 * <[email protected]> wrote this file. As long as you retain this notice you
40 * can do whatever you want with this stuff. If we meet some day, and you think
41 * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
42 * ----------------------------------------------------------------------------
43 *
44 * Major Changelog:
45 *
46 * Dag-Erling Smørgrav
47 * 9 Jun 1998
48 *
49 * Incorporated into libfetch
50 *
51 * Jordan K. Hubbard
52 * 17 Jan 1996
53 *
54 * Turned inside out. Now returns xfers as new file ids, not as a special
55 * `state' of FTP_t
56 *
57 * $ftpioId: ftpio.c,v 1.30 1998/04/11 07:28:53 phk Exp $
58 *
59 */
60
61 #include <sys/param.h>
62 #include <sys/socket.h>
63 #include <netinet/in.h>
64
65 #include <ctype.h>
66 #include <err.h>
67 #include <errno.h>
68 #include <fcntl.h>
69 #include <netdb.h>
70 #include <stdarg.h>
71 #include <stdint.h>
72 #include <stdio.h>
73 #include <stdlib.h>
74 #include <string.h>
75 #include <time.h>
76 #include <unistd.h>
77
78 #include "fetch.h"
79 #include "common.h"
80 #include "ftperr.h"
81
82 #define FTP_ANONYMOUS_USER "anonymous"
83
84 #define FTP_CONNECTION_ALREADY_OPEN 125
85 #define FTP_OPEN_DATA_CONNECTION 150
86 #define FTP_OK 200
87 #define FTP_FILE_STATUS 213
88 #define FTP_SERVICE_READY 220
89 #define FTP_TRANSFER_COMPLETE 226
90 #define FTP_PASSIVE_MODE 227
91 #define FTP_LPASSIVE_MODE 228
92 #define FTP_EPASSIVE_MODE 229
93 #define FTP_LOGGED_IN 230
94 #define FTP_FILE_ACTION_OK 250
95 #define FTP_DIRECTORY_CREATED 257 /* multiple meanings */
96 #define FTP_FILE_CREATED 257 /* multiple meanings */
97 #define FTP_WORKING_DIRECTORY 257 /* multiple meanings */
98 #define FTP_NEED_PASSWORD 331
99 #define FTP_NEED_ACCOUNT 332
100 #define FTP_FILE_OK 350
101 #define FTP_SYNTAX_ERROR 500
102 #define FTP_PROTOCOL_ERROR 999
103
104 static struct url cached_host;
105 static conn_t *cached_connection;
106
107 #define isftpreply(foo) \
108 (isdigit((unsigned char)foo[0]) && \
109 isdigit((unsigned char)foo[1]) && \
110 isdigit((unsigned char)foo[2]) && \
111 (foo[3] == ' ' || foo[3] == '\0'))
112 #define isftpinfo(foo) \
113 (isdigit((unsigned char)foo[0]) && \
114 isdigit((unsigned char)foo[1]) && \
115 isdigit((unsigned char)foo[2]) && \
116 foo[3] == '-')
117
118 /*
119 * Translate IPv4 mapped IPv6 address to IPv4 address
120 */
121 static void
unmappedaddr(struct sockaddr_in6 * sin6)122 unmappedaddr(struct sockaddr_in6 *sin6)
123 {
124 struct sockaddr_in *sin4;
125 u_int32_t addr;
126 int port;
127
128 if (sin6->sin6_family != AF_INET6 ||
129 !IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr))
130 return;
131 sin4 = (struct sockaddr_in *)sin6;
132 addr = *(u_int32_t *)(uintptr_t)&sin6->sin6_addr.s6_addr[12];
133 port = sin6->sin6_port;
134 memset(sin4, 0, sizeof(struct sockaddr_in));
135 sin4->sin_addr.s_addr = addr;
136 sin4->sin_port = port;
137 sin4->sin_family = AF_INET;
138 sin4->sin_len = sizeof(struct sockaddr_in);
139 }
140
141 /*
142 * Get server response
143 */
144 static int
ftp_chkerr(conn_t * conn)145 ftp_chkerr(conn_t *conn)
146 {
147 if (fetch_getln(conn) == -1) {
148 fetch_syserr();
149 return (-1);
150 }
151 if (isftpinfo(conn->buf)) {
152 while (conn->buflen && !isftpreply(conn->buf)) {
153 if (fetch_getln(conn) == -1) {
154 fetch_syserr();
155 return (-1);
156 }
157 }
158 }
159
160 while (conn->buflen &&
161 isspace((unsigned char)conn->buf[conn->buflen - 1]))
162 conn->buflen--;
163 conn->buf[conn->buflen] = '\0';
164
165 if (!isftpreply(conn->buf)) {
166 ftp_seterr(FTP_PROTOCOL_ERROR);
167 return (-1);
168 }
169
170 conn->err = (conn->buf[0] - '0') * 100
171 + (conn->buf[1] - '0') * 10
172 + (conn->buf[2] - '0');
173
174 return (conn->err);
175 }
176
177 /*
178 * Send a command and check reply
179 */
180 static int
ftp_cmd(conn_t * conn,const char * fmt,...)181 ftp_cmd(conn_t *conn, const char *fmt, ...)
182 {
183 va_list ap;
184 size_t len;
185 char *msg;
186 int r;
187
188 va_start(ap, fmt);
189 len = vasprintf(&msg, fmt, ap);
190 va_end(ap);
191
192 if (msg == NULL) {
193 errno = ENOMEM;
194 fetch_syserr();
195 return (-1);
196 }
197
198 r = fetch_putln(conn, msg, len);
199 free(msg);
200
201 if (r == -1) {
202 fetch_syserr();
203 return (-1);
204 }
205
206 return (ftp_chkerr(conn));
207 }
208
209 /*
210 * Return a pointer to the filename part of a path
211 */
212 static const char *
ftp_filename(const char * file,int * len,int * type)213 ftp_filename(const char *file, int *len, int *type)
214 {
215 const char *s;
216
217 if ((s = strrchr(file, '/')) == NULL)
218 s = file;
219 else
220 s = s + 1;
221 *len = strlen(s);
222 if (*len > 7 && strncmp(s + *len - 7, ";type=", 6) == 0) {
223 *type = s[*len - 1];
224 *len -= 7;
225 } else {
226 *type = '\0';
227 }
228 return (s);
229 }
230
231 /*
232 * Get current working directory from the reply to a CWD, PWD or CDUP
233 * command.
234 */
235 static int
ftp_pwd(conn_t * conn,char * pwd,size_t pwdlen)236 ftp_pwd(conn_t *conn, char *pwd, size_t pwdlen)
237 {
238 char *src, *dst, *end;
239 int q;
240
241 if (conn->err != FTP_WORKING_DIRECTORY &&
242 conn->err != FTP_FILE_ACTION_OK)
243 return (FTP_PROTOCOL_ERROR);
244 end = conn->buf + conn->buflen;
245 src = conn->buf + 4;
246 if (src >= end || *src++ != '"')
247 return (FTP_PROTOCOL_ERROR);
248 for (q = 0, dst = pwd; src < end && pwdlen--; ++src) {
249 if (!q && *src == '"')
250 q = 1;
251 else if (q && *src != '"')
252 break;
253 else if (q)
254 *dst++ = '"', q = 0;
255 else
256 *dst++ = *src;
257 }
258 if (!pwdlen)
259 return (FTP_PROTOCOL_ERROR);
260 *dst = '\0';
261 #if 0
262 DEBUGF("pwd: [%s]\n", pwd);
263 #endif
264 return (FTP_OK);
265 }
266
267 /*
268 * Change working directory to the directory that contains the specified
269 * file.
270 */
271 static int
ftp_cwd(conn_t * conn,const char * file)272 ftp_cwd(conn_t *conn, const char *file)
273 {
274 const char *beg, *end;
275 char pwd[PATH_MAX];
276 int e, i, len;
277
278 /* If no slashes in name, no need to change dirs. */
279 if ((end = strrchr(file, '/')) == NULL)
280 return (0);
281 if ((e = ftp_cmd(conn, "PWD")) != FTP_WORKING_DIRECTORY ||
282 (e = ftp_pwd(conn, pwd, sizeof(pwd))) != FTP_OK) {
283 ftp_seterr(e);
284 return (-1);
285 }
286 for (;;) {
287 len = strlen(pwd);
288
289 /* Look for a common prefix between PWD and dir to fetch. */
290 for (i = 0; i <= len && i <= end - file; ++i)
291 if (pwd[i] != file[i])
292 break;
293 #if 0
294 DEBUGF("have: [%.*s|%s]\n", i, pwd, pwd + i);
295 DEBUGF("want: [%.*s|%s]\n", i, file, file + i);
296 #endif
297 /* Keep going up a dir until we have a matching prefix. */
298 if (pwd[i] == '\0' && (file[i - 1] == '/' || file[i] == '/'))
299 break;
300 if ((e = ftp_cmd(conn, "CDUP")) != FTP_FILE_ACTION_OK ||
301 (e = ftp_cmd(conn, "PWD")) != FTP_WORKING_DIRECTORY ||
302 (e = ftp_pwd(conn, pwd, sizeof(pwd))) != FTP_OK) {
303 ftp_seterr(e);
304 return (-1);
305 }
306 }
307
308 #ifdef FTP_COMBINE_CWDS
309 /* Skip leading slashes, even "////". */
310 for (beg = file + i; beg < end && *beg == '/'; ++beg, ++i)
311 /* nothing */ ;
312
313 /* If there is no trailing dir, we're already there. */
314 if (beg >= end)
315 return (0);
316
317 /* Change to the directory all in one chunk (e.g., foo/bar/baz). */
318 e = ftp_cmd(conn, "CWD %.*s", (int)(end - beg), beg);
319 if (e == FTP_FILE_ACTION_OK)
320 return (0);
321 #endif /* FTP_COMBINE_CWDS */
322
323 /* That didn't work so go back to legacy behavior (multiple CWDs). */
324 for (beg = file + i; beg < end; beg = file + i + 1) {
325 while (*beg == '/')
326 ++beg, ++i;
327 for (++i; file + i < end && file[i] != '/'; ++i)
328 /* nothing */ ;
329 e = ftp_cmd(conn, "CWD %.*s", file + i - beg, beg);
330 if (e != FTP_FILE_ACTION_OK) {
331 ftp_seterr(e);
332 return (-1);
333 }
334 }
335 return (0);
336 }
337
338 /*
339 * Set transfer mode and data type
340 */
341 static int
ftp_mode_type(conn_t * conn,int mode,int type)342 ftp_mode_type(conn_t *conn, int mode, int type)
343 {
344 int e;
345
346 switch (mode) {
347 case 0:
348 case 's':
349 mode = 'S';
350 case 'S':
351 break;
352 default:
353 return (FTP_PROTOCOL_ERROR);
354 }
355 if ((e = ftp_cmd(conn, "MODE %c", mode)) != FTP_OK) {
356 if (mode == 'S') {
357 /*
358 * Stream mode is supposed to be the default - so
359 * much so that some servers not only do not
360 * support any other mode, but do not support the
361 * MODE command at all.
362 *
363 * If "MODE S" fails, it is unlikely that we
364 * previously succeeded in setting a different
365 * mode. Therefore, we simply hope that the
366 * server is already in the correct mode, and
367 * silently ignore the failure.
368 */
369 } else {
370 return (e);
371 }
372 }
373
374 switch (type) {
375 case 0:
376 case 'i':
377 type = 'I';
378 case 'I':
379 break;
380 case 'a':
381 type = 'A';
382 case 'A':
383 break;
384 case 'd':
385 type = 'D';
386 case 'D':
387 /* can't handle yet */
388 default:
389 return (FTP_PROTOCOL_ERROR);
390 }
391 if ((e = ftp_cmd(conn, "TYPE %c", type)) != FTP_OK)
392 return (e);
393
394 return (FTP_OK);
395 }
396
397 /*
398 * Request and parse file stats
399 */
400 static int
ftp_stat(conn_t * conn,const char * file,struct url_stat * us)401 ftp_stat(conn_t *conn, const char *file, struct url_stat *us)
402 {
403 char *ln;
404 const char *filename;
405 int filenamelen, type;
406 struct tm tm;
407 time_t t;
408 int e;
409
410 us->size = -1;
411 us->atime = us->mtime = 0;
412
413 filename = ftp_filename(file, &filenamelen, &type);
414
415 if ((e = ftp_mode_type(conn, 0, type)) != FTP_OK) {
416 ftp_seterr(e);
417 return (-1);
418 }
419
420 e = ftp_cmd(conn, "SIZE %.*s", filenamelen, filename);
421 if (e != FTP_FILE_STATUS) {
422 ftp_seterr(e);
423 return (-1);
424 }
425 for (ln = conn->buf + 4; *ln && isspace((unsigned char)*ln); ln++)
426 /* nothing */ ;
427 for (us->size = 0; *ln && isdigit((unsigned char)*ln); ln++)
428 us->size = us->size * 10 + *ln - '0';
429 if (*ln && !isspace((unsigned char)*ln)) {
430 ftp_seterr(FTP_PROTOCOL_ERROR);
431 us->size = -1;
432 return (-1);
433 }
434 if (us->size == 0)
435 us->size = -1;
436 DEBUGF("size: [%lld]\n", (long long)us->size);
437
438 e = ftp_cmd(conn, "MDTM %.*s", filenamelen, filename);
439 if (e != FTP_FILE_STATUS) {
440 ftp_seterr(e);
441 return (-1);
442 }
443 for (ln = conn->buf + 4; *ln && isspace((unsigned char)*ln); ln++)
444 /* nothing */ ;
445 switch (strspn(ln, "0123456789")) {
446 case 14:
447 break;
448 case 15:
449 ln++;
450 ln[0] = '2';
451 ln[1] = '0';
452 break;
453 default:
454 ftp_seterr(FTP_PROTOCOL_ERROR);
455 return (-1);
456 }
457 if (sscanf(ln, "%04d%02d%02d%02d%02d%02d",
458 &tm.tm_year, &tm.tm_mon, &tm.tm_mday,
459 &tm.tm_hour, &tm.tm_min, &tm.tm_sec) != 6) {
460 ftp_seterr(FTP_PROTOCOL_ERROR);
461 return (-1);
462 }
463 tm.tm_mon--;
464 tm.tm_year -= 1900;
465 tm.tm_isdst = -1;
466 t = timegm(&tm);
467 if (t == (time_t)-1)
468 t = time(NULL);
469 us->mtime = t;
470 us->atime = t;
471 DEBUGF("last modified: [%04d-%02d-%02d %02d:%02d:%02d]\n",
472 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday,
473 tm.tm_hour, tm.tm_min, tm.tm_sec);
474 return (0);
475 }
476
477 /*
478 * I/O functions for FTP
479 */
480 struct ftpio {
481 conn_t *cconn; /* Control connection */
482 conn_t *dconn; /* Data connection */
483 int dir; /* Direction */
484 int eof; /* EOF reached */
485 int err; /* Error code */
486 };
487
488 static int ftp_readfn(void *, char *, int);
489 static int ftp_writefn(void *, const char *, int);
490 static fpos_t ftp_seekfn(void *, fpos_t, int);
491 static int ftp_closefn(void *);
492
493 static int
ftp_readfn(void * v,char * buf,int len)494 ftp_readfn(void *v, char *buf, int len)
495 {
496 struct ftpio *io;
497 int r;
498
499 io = (struct ftpio *)v;
500 if (io == NULL) {
501 errno = EBADF;
502 return (-1);
503 }
504 if (io->cconn == NULL || io->dconn == NULL || io->dir == O_WRONLY) {
505 errno = EBADF;
506 return (-1);
507 }
508 if (io->err) {
509 errno = io->err;
510 return (-1);
511 }
512 if (io->eof)
513 return (0);
514 r = fetch_read(io->dconn, buf, len);
515 if (r > 0)
516 return (r);
517 if (r == 0) {
518 io->eof = 1;
519 return (0);
520 }
521 if (errno != EINTR)
522 io->err = errno;
523 return (-1);
524 }
525
526 static int
ftp_writefn(void * v,const char * buf,int len)527 ftp_writefn(void *v, const char *buf, int len)
528 {
529 struct ftpio *io;
530 int w;
531
532 io = (struct ftpio *)v;
533 if (io == NULL) {
534 errno = EBADF;
535 return (-1);
536 }
537 if (io->cconn == NULL || io->dconn == NULL || io->dir == O_RDONLY) {
538 errno = EBADF;
539 return (-1);
540 }
541 if (io->err) {
542 errno = io->err;
543 return (-1);
544 }
545 w = fetch_write(io->dconn, buf, len);
546 if (w >= 0)
547 return (w);
548 if (errno != EINTR)
549 io->err = errno;
550 return (-1);
551 }
552
553 static fpos_t
ftp_seekfn(void * v,fpos_t pos __unused,int whence __unused)554 ftp_seekfn(void *v, fpos_t pos __unused, int whence __unused)
555 {
556 struct ftpio *io;
557
558 io = (struct ftpio *)v;
559 if (io == NULL) {
560 errno = EBADF;
561 return (-1);
562 }
563 errno = ESPIPE;
564 return (-1);
565 }
566
567 static int
ftp_closefn(void * v)568 ftp_closefn(void *v)
569 {
570 struct ftpio *io;
571 int r;
572
573 io = (struct ftpio *)v;
574 if (io == NULL) {
575 errno = EBADF;
576 return (-1);
577 }
578 if (io->dir == -1)
579 return (0);
580 if (io->cconn == NULL || io->dconn == NULL) {
581 errno = EBADF;
582 return (-1);
583 }
584 fetch_close(io->dconn);
585 io->dir = -1;
586 io->dconn = NULL;
587 DEBUGF("Waiting for final status\n");
588 r = ftp_chkerr(io->cconn);
589 if (io->cconn == cached_connection && io->cconn->ref == 1)
590 cached_connection = NULL;
591 fetch_close(io->cconn);
592 free(io);
593 return (r == FTP_TRANSFER_COMPLETE) ? 0 : -1;
594 }
595
596 static FILE *
ftp_setup(conn_t * cconn,conn_t * dconn,int mode)597 ftp_setup(conn_t *cconn, conn_t *dconn, int mode)
598 {
599 struct ftpio *io;
600 FILE *f;
601
602 if (cconn == NULL || dconn == NULL)
603 return (NULL);
604 if ((io = malloc(sizeof(*io))) == NULL)
605 return (NULL);
606 io->cconn = cconn;
607 io->dconn = dconn;
608 io->dir = mode;
609 io->eof = io->err = 0;
610 f = funopen(io, ftp_readfn, ftp_writefn, ftp_seekfn, ftp_closefn);
611 if (f == NULL)
612 free(io);
613 return (f);
614 }
615
616 /*
617 * Transfer file
618 */
619 static FILE *
ftp_transfer(conn_t * conn,const char * oper,const char * file,int mode,off_t offset,const char * flags)620 ftp_transfer(conn_t *conn, const char *oper, const char *file,
621 int mode, off_t offset, const char *flags)
622 {
623 struct sockaddr_storage sa;
624 struct sockaddr_in6 *sin6;
625 struct sockaddr_in *sin4;
626 const char *bindaddr;
627 const char *filename;
628 int filenamelen, type;
629 int low, pasv, verbose;
630 int e, sd = -1;
631 socklen_t l;
632 char *s;
633 FILE *df;
634
635 /* check flags */
636 low = CHECK_FLAG('l');
637 pasv = CHECK_FLAG('p') || !CHECK_FLAG('P');
638 verbose = CHECK_FLAG('v');
639
640 /* passive mode */
641 if ((s = getenv("FTP_PASSIVE_MODE")) != NULL)
642 pasv = (strncasecmp(s, "no", 2) != 0);
643
644 /* isolate filename */
645 filename = ftp_filename(file, &filenamelen, &type);
646
647 /* set transfer mode and data type */
648 if ((e = ftp_mode_type(conn, 0, type)) != FTP_OK)
649 goto ouch;
650
651 /* find our own address, bind, and listen */
652 l = sizeof(sa);
653 if (getsockname(conn->sd, (struct sockaddr *)&sa, &l) == -1)
654 goto sysouch;
655 if (sa.ss_family == AF_INET6)
656 unmappedaddr((struct sockaddr_in6 *)&sa);
657
658 /* open data socket */
659 if ((sd = socket(sa.ss_family, SOCK_STREAM, IPPROTO_TCP)) == -1) {
660 fetch_syserr();
661 return (NULL);
662 }
663
664 if (pasv) {
665 u_char addr[64];
666 char *ln, *p;
667 unsigned int i;
668 int port;
669
670 /* send PASV command */
671 if (verbose)
672 fetch_info("setting passive mode");
673 switch (sa.ss_family) {
674 case AF_INET:
675 if ((e = ftp_cmd(conn, "PASV")) != FTP_PASSIVE_MODE)
676 goto ouch;
677 break;
678 case AF_INET6:
679 if ((e = ftp_cmd(conn, "EPSV")) != FTP_EPASSIVE_MODE) {
680 if (e == -1)
681 goto ouch;
682 if ((e = ftp_cmd(conn, "LPSV")) !=
683 FTP_LPASSIVE_MODE)
684 goto ouch;
685 }
686 break;
687 default:
688 e = FTP_PROTOCOL_ERROR; /* XXX: error code should be prepared */
689 goto ouch;
690 }
691
692 /*
693 * Find address and port number. The reply to the PASV command
694 * is IMHO the one and only weak point in the FTP protocol.
695 */
696 ln = conn->buf;
697 switch (e) {
698 case FTP_PASSIVE_MODE:
699 case FTP_LPASSIVE_MODE:
700 for (p = ln + 3; *p && !isdigit((unsigned char)*p); p++)
701 /* nothing */ ;
702 if (!*p) {
703 e = FTP_PROTOCOL_ERROR;
704 goto ouch;
705 }
706 l = (e == FTP_PASSIVE_MODE ? 6 : 21);
707 for (i = 0; *p && i < l; i++, p++) {
708 addr[i] = strtol(p, &p, 10);
709 if (*p == '\0' && i < l - 1)
710 break;
711 }
712 if (i < l) {
713 e = FTP_PROTOCOL_ERROR;
714 goto ouch;
715 }
716 break;
717 case FTP_EPASSIVE_MODE:
718 for (p = ln + 3; *p && *p != '('; p++)
719 /* nothing */ ;
720 if (!*p) {
721 e = FTP_PROTOCOL_ERROR;
722 goto ouch;
723 }
724 ++p;
725 if (sscanf(p, "%c%c%c%d%c", &addr[0], &addr[1], &addr[2],
726 &port, &addr[3]) != 5 ||
727 addr[0] != addr[1] ||
728 addr[0] != addr[2] || addr[0] != addr[3]) {
729 e = FTP_PROTOCOL_ERROR;
730 goto ouch;
731 }
732 break;
733 }
734
735 /* seek to required offset */
736 if (offset)
737 if (ftp_cmd(conn, "REST %lu", (u_long)offset) != FTP_FILE_OK)
738 goto sysouch;
739
740 /* construct sockaddr for data socket */
741 l = sizeof(sa);
742 if (getpeername(conn->sd, (struct sockaddr *)&sa, &l) == -1)
743 goto sysouch;
744 if (sa.ss_family == AF_INET6)
745 unmappedaddr((struct sockaddr_in6 *)&sa);
746 switch (sa.ss_family) {
747 case AF_INET6:
748 sin6 = (struct sockaddr_in6 *)&sa;
749 if (e == FTP_EPASSIVE_MODE)
750 sin6->sin6_port = htons(port);
751 else {
752 memcpy(&sin6->sin6_addr, addr + 2, 16);
753 memcpy(&sin6->sin6_port, addr + 19, 2);
754 }
755 break;
756 case AF_INET:
757 sin4 = (struct sockaddr_in *)&sa;
758 if (e == FTP_EPASSIVE_MODE)
759 sin4->sin_port = htons(port);
760 else {
761 memcpy(&sin4->sin_addr, addr, 4);
762 memcpy(&sin4->sin_port, addr + 4, 2);
763 }
764 break;
765 default:
766 e = FTP_PROTOCOL_ERROR; /* XXX: error code should be prepared */
767 break;
768 }
769
770 /* connect to data port */
771 if (verbose)
772 fetch_info("opening data connection");
773 bindaddr = getenv("FETCH_BIND_ADDRESS");
774 if (bindaddr != NULL && *bindaddr != '\0' &&
775 (e = fetch_bind(sd, sa.ss_family, bindaddr)) != 0)
776 goto ouch;
777 if (connect(sd, (struct sockaddr *)&sa, sa.ss_len) == -1)
778 goto sysouch;
779
780 /* make the server initiate the transfer */
781 if (verbose)
782 fetch_info("initiating transfer");
783 e = ftp_cmd(conn, "%s %.*s", oper, filenamelen, filename);
784 if (e != FTP_CONNECTION_ALREADY_OPEN && e != FTP_OPEN_DATA_CONNECTION)
785 goto ouch;
786
787 } else {
788 u_int32_t a;
789 u_short p;
790 int arg, d;
791 char *ap;
792 char hname[INET6_ADDRSTRLEN];
793
794 switch (sa.ss_family) {
795 case AF_INET6:
796 ((struct sockaddr_in6 *)&sa)->sin6_port = 0;
797 #ifdef IPV6_PORTRANGE
798 arg = low ? IPV6_PORTRANGE_DEFAULT : IPV6_PORTRANGE_HIGH;
799 if (setsockopt(sd, IPPROTO_IPV6, IPV6_PORTRANGE,
800 (char *)&arg, sizeof(arg)) == -1)
801 goto sysouch;
802 #endif
803 break;
804 case AF_INET:
805 ((struct sockaddr_in *)&sa)->sin_port = 0;
806 arg = low ? IP_PORTRANGE_DEFAULT : IP_PORTRANGE_HIGH;
807 if (setsockopt(sd, IPPROTO_IP, IP_PORTRANGE,
808 (char *)&arg, sizeof(arg)) == -1)
809 goto sysouch;
810 break;
811 }
812 if (verbose)
813 fetch_info("binding data socket");
814 if (bind(sd, (struct sockaddr *)&sa, sa.ss_len) == -1)
815 goto sysouch;
816 if (listen(sd, 1) == -1)
817 goto sysouch;
818
819 /* find what port we're on and tell the server */
820 if (getsockname(sd, (struct sockaddr *)&sa, &l) == -1)
821 goto sysouch;
822 switch (sa.ss_family) {
823 case AF_INET:
824 sin4 = (struct sockaddr_in *)&sa;
825 a = ntohl(sin4->sin_addr.s_addr);
826 p = ntohs(sin4->sin_port);
827 e = ftp_cmd(conn, "PORT %d,%d,%d,%d,%d,%d",
828 (a >> 24) & 0xff, (a >> 16) & 0xff,
829 (a >> 8) & 0xff, a & 0xff,
830 (p >> 8) & 0xff, p & 0xff);
831 break;
832 case AF_INET6:
833 #define UC(b) (((int)b)&0xff)
834 e = -1;
835 sin6 = (struct sockaddr_in6 *)&sa;
836 sin6->sin6_scope_id = 0;
837 if (getnameinfo((struct sockaddr *)&sa, sa.ss_len,
838 hname, sizeof(hname),
839 NULL, 0, NI_NUMERICHOST) == 0) {
840 e = ftp_cmd(conn, "EPRT |%d|%s|%d|", 2, hname,
841 htons(sin6->sin6_port));
842 if (e == -1)
843 goto ouch;
844 }
845 if (e != FTP_OK) {
846 ap = (char *)&sin6->sin6_addr;
847 e = ftp_cmd(conn,
848 "LPRT %d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d",
849 6, 16,
850 UC(ap[0]), UC(ap[1]), UC(ap[2]), UC(ap[3]),
851 UC(ap[4]), UC(ap[5]), UC(ap[6]), UC(ap[7]),
852 UC(ap[8]), UC(ap[9]), UC(ap[10]), UC(ap[11]),
853 UC(ap[12]), UC(ap[13]), UC(ap[14]), UC(ap[15]),
854 2,
855 (ntohs(sin6->sin6_port) >> 8) & 0xff,
856 ntohs(sin6->sin6_port) & 0xff);
857 }
858 break;
859 default:
860 e = FTP_PROTOCOL_ERROR; /* XXX: error code should be prepared */
861 goto ouch;
862 }
863 if (e != FTP_OK)
864 goto ouch;
865
866 /* seek to required offset */
867 if (offset)
868 if (ftp_cmd(conn, "REST %ju", (uintmax_t)offset) != FTP_FILE_OK)
869 goto sysouch;
870
871 /* make the server initiate the transfer */
872 if (verbose)
873 fetch_info("initiating transfer");
874 e = ftp_cmd(conn, "%s %.*s", oper, filenamelen, filename);
875 if (e != FTP_CONNECTION_ALREADY_OPEN && e != FTP_OPEN_DATA_CONNECTION)
876 goto ouch;
877
878 /* accept the incoming connection and go to town */
879 if ((d = accept(sd, NULL, NULL)) == -1)
880 goto sysouch;
881 close(sd);
882 sd = d;
883 }
884
885 if ((df = ftp_setup(conn, fetch_reopen(sd), mode)) == NULL)
886 goto sysouch;
887 return (df);
888
889 sysouch:
890 fetch_syserr();
891 if (sd >= 0)
892 close(sd);
893 return (NULL);
894
895 ouch:
896 if (e != -1)
897 ftp_seterr(e);
898 if (sd >= 0)
899 close(sd);
900 return (NULL);
901 }
902
903 /*
904 * Authenticate
905 */
906 static int
ftp_authenticate(conn_t * conn,struct url * url,struct url * purl)907 ftp_authenticate(conn_t *conn, struct url *url, struct url *purl)
908 {
909 const char *user, *pwd, *logname;
910 char pbuf[MAXHOSTNAMELEN + MAXLOGNAME + 1];
911 int e, len;
912
913 /* XXX FTP_AUTH, and maybe .netrc */
914
915 /* send user name and password */
916 if (url->user[0] == '\0')
917 fetch_netrc_auth(url);
918 user = url->user;
919 if (*user == '\0')
920 if ((user = getenv("FTP_LOGIN")) != NULL)
921 DEBUGF("FTP_LOGIN=%s\n", user);
922 if (user == NULL || *user == '\0')
923 user = FTP_ANONYMOUS_USER;
924 if (purl && url->port == fetch_default_port(url->scheme))
925 e = ftp_cmd(conn, "USER %s@%s", user, url->host);
926 else if (purl)
927 e = ftp_cmd(conn, "USER %s@%s@%d", user, url->host, url->port);
928 else
929 e = ftp_cmd(conn, "USER %s", user);
930
931 /* did the server request a password? */
932 if (e == FTP_NEED_PASSWORD) {
933 pwd = url->pwd;
934 if (*pwd == '\0')
935 if ((pwd = getenv("FTP_PASSWORD")) != NULL)
936 DEBUGF("FTP_PASSWORD=%s\n", pwd);
937 if (pwd == NULL || *pwd == '\0') {
938 if ((logname = getlogin()) == NULL)
939 logname = FTP_ANONYMOUS_USER;
940 if ((len = snprintf(pbuf, MAXLOGNAME + 1, "%s@", logname)) < 0)
941 len = 0;
942 else if (len > MAXLOGNAME)
943 len = MAXLOGNAME;
944 gethostname(pbuf + len, sizeof(pbuf) - len);
945 pwd = pbuf;
946 }
947 e = ftp_cmd(conn, "PASS %s", pwd);
948 }
949
950 return (e);
951 }
952
953 /*
954 * Log on to FTP server
955 */
956 static conn_t *
ftp_connect(struct url * url,struct url * purl,const char * flags)957 ftp_connect(struct url *url, struct url *purl, const char *flags)
958 {
959 conn_t *conn;
960 int e, direct, verbose;
961 #ifdef INET6
962 int af = AF_UNSPEC;
963 #else
964 int af = AF_INET;
965 #endif
966
967 direct = CHECK_FLAG('d');
968 verbose = CHECK_FLAG('v');
969 if (CHECK_FLAG('4'))
970 af = AF_INET;
971 else if (CHECK_FLAG('6'))
972 af = AF_INET6;
973
974 if (direct)
975 purl = NULL;
976
977 /* check for proxy */
978 if (purl) {
979 /* XXX proxy authentication! */
980 conn = fetch_connect(purl->host, purl->port, af, verbose);
981 } else {
982 /* no proxy, go straight to target */
983 conn = fetch_connect(url->host, url->port, af, verbose);
984 purl = NULL;
985 }
986
987 /* check connection */
988 if (conn == NULL)
989 /* fetch_connect() has already set an error code */
990 return (NULL);
991
992 /* expect welcome message */
993 if ((e = ftp_chkerr(conn)) != FTP_SERVICE_READY)
994 goto fouch;
995
996 /* authenticate */
997 if ((e = ftp_authenticate(conn, url, purl)) != FTP_LOGGED_IN)
998 goto fouch;
999
1000 /* TODO: Request extended features supported, if any (RFC 3659). */
1001
1002 /* done */
1003 return (conn);
1004
1005 fouch:
1006 if (e != -1)
1007 ftp_seterr(e);
1008 fetch_close(conn);
1009 return (NULL);
1010 }
1011
1012 /*
1013 * Disconnect from server
1014 */
1015 static void
ftp_disconnect(conn_t * conn)1016 ftp_disconnect(conn_t *conn)
1017 {
1018 (void)ftp_cmd(conn, "QUIT");
1019 if (conn == cached_connection && conn->ref == 1)
1020 cached_connection = NULL;
1021 fetch_close(conn);
1022 }
1023
1024 /*
1025 * Check if we're already connected
1026 */
1027 static int
ftp_isconnected(struct url * url)1028 ftp_isconnected(struct url *url)
1029 {
1030 return (cached_connection
1031 && (strcmp(url->host, cached_host.host) == 0)
1032 && (strcmp(url->user, cached_host.user) == 0)
1033 && (strcmp(url->pwd, cached_host.pwd) == 0)
1034 && (url->port == cached_host.port));
1035 }
1036
1037 /*
1038 * Check the cache, reconnect if no luck
1039 */
1040 static conn_t *
ftp_cached_connect(struct url * url,struct url * purl,const char * flags)1041 ftp_cached_connect(struct url *url, struct url *purl, const char *flags)
1042 {
1043 conn_t *conn;
1044 int e;
1045
1046 /* set default port */
1047 if (!url->port)
1048 url->port = fetch_default_port(url->scheme);
1049
1050 /* try to use previously cached connection */
1051 if (ftp_isconnected(url)) {
1052 e = ftp_cmd(cached_connection, "NOOP");
1053 if (e == FTP_OK || e == FTP_SYNTAX_ERROR)
1054 return (fetch_ref(cached_connection));
1055 }
1056
1057 /* connect to server */
1058 if ((conn = ftp_connect(url, purl, flags)) == NULL)
1059 return (NULL);
1060 if (cached_connection)
1061 ftp_disconnect(cached_connection);
1062 cached_connection = fetch_ref(conn);
1063 memcpy(&cached_host, url, sizeof(*url));
1064 return (conn);
1065 }
1066
1067 /*
1068 * Check the proxy settings
1069 */
1070 static struct url *
ftp_get_proxy(struct url * url,const char * flags)1071 ftp_get_proxy(struct url * url, const char *flags)
1072 {
1073 struct url *purl;
1074 char *p;
1075
1076 if (flags != NULL && strchr(flags, 'd') != NULL)
1077 return (NULL);
1078 if (fetch_no_proxy_match(url->host))
1079 return (NULL);
1080 if (((p = getenv("FTP_PROXY")) || (p = getenv("ftp_proxy")) ||
1081 (p = getenv("HTTP_PROXY")) || (p = getenv("http_proxy"))) &&
1082 *p && (purl = fetchParseURL(p)) != NULL) {
1083 if (!*purl->scheme) {
1084 if (getenv("FTP_PROXY") || getenv("ftp_proxy"))
1085 strcpy(purl->scheme, SCHEME_FTP);
1086 else
1087 strcpy(purl->scheme, SCHEME_HTTP);
1088 }
1089 if (!purl->port)
1090 purl->port = fetch_default_proxy_port(purl->scheme);
1091 if (strcmp(purl->scheme, SCHEME_FTP) == 0 ||
1092 strcmp(purl->scheme, SCHEME_HTTP) == 0)
1093 return (purl);
1094 fetchFreeURL(purl);
1095 }
1096 return (NULL);
1097 }
1098
1099 /*
1100 * Process an FTP request
1101 */
1102 FILE *
ftp_request(struct url * url,const char * op,struct url_stat * us,struct url * purl,const char * flags)1103 ftp_request(struct url *url, const char *op, struct url_stat *us,
1104 struct url *purl, const char *flags)
1105 {
1106 conn_t *conn;
1107 int oflag;
1108
1109 /* check if we should use HTTP instead */
1110 if (purl && (strcmp(purl->scheme, SCHEME_HTTP) == 0 ||
1111 strcmp(purl->scheme, SCHEME_HTTPS) == 0)) {
1112 if (strcmp(op, "STAT") == 0)
1113 return (http_request(url, "HEAD", us, purl, flags));
1114 else if (strcmp(op, "RETR") == 0)
1115 return (http_request(url, "GET", us, purl, flags));
1116 /*
1117 * Our HTTP code doesn't support PUT requests yet, so try
1118 * a direct connection.
1119 */
1120 }
1121
1122 /* connect to server */
1123 conn = ftp_cached_connect(url, purl, flags);
1124 if (purl)
1125 fetchFreeURL(purl);
1126 if (conn == NULL)
1127 return (NULL);
1128
1129 /* change directory */
1130 if (ftp_cwd(conn, url->doc) == -1)
1131 goto errsock;
1132
1133 /* stat file */
1134 if (us && ftp_stat(conn, url->doc, us) == -1
1135 && fetchLastErrCode != FETCH_PROTO
1136 && fetchLastErrCode != FETCH_UNAVAIL)
1137 goto errsock;
1138
1139 /* just a stat */
1140 if (strcmp(op, "STAT") == 0) {
1141 --conn->ref;
1142 ftp_disconnect(conn);
1143 return (FILE *)1; /* bogus return value */
1144 }
1145 if (strcmp(op, "STOR") == 0 || strcmp(op, "APPE") == 0)
1146 oflag = O_WRONLY;
1147 else
1148 oflag = O_RDONLY;
1149
1150 /* initiate the transfer */
1151 return (ftp_transfer(conn, op, url->doc, oflag, url->offset, flags));
1152
1153 errsock:
1154 ftp_disconnect(conn);
1155 return (NULL);
1156 }
1157
1158 /*
1159 * Get and stat file
1160 */
1161 FILE *
fetchXGetFTP(struct url * url,struct url_stat * us,const char * flags)1162 fetchXGetFTP(struct url *url, struct url_stat *us, const char *flags)
1163 {
1164 return (ftp_request(url, "RETR", us, ftp_get_proxy(url, flags), flags));
1165 }
1166
1167 /*
1168 * Get file
1169 */
1170 FILE *
fetchGetFTP(struct url * url,const char * flags)1171 fetchGetFTP(struct url *url, const char *flags)
1172 {
1173 return (fetchXGetFTP(url, NULL, flags));
1174 }
1175
1176 /*
1177 * Put file
1178 */
1179 FILE *
fetchPutFTP(struct url * url,const char * flags)1180 fetchPutFTP(struct url *url, const char *flags)
1181 {
1182 return (ftp_request(url, CHECK_FLAG('a') ? "APPE" : "STOR", NULL,
1183 ftp_get_proxy(url, flags), flags));
1184 }
1185
1186 /*
1187 * Get file stats
1188 */
1189 int
fetchStatFTP(struct url * url,struct url_stat * us,const char * flags)1190 fetchStatFTP(struct url *url, struct url_stat *us, const char *flags)
1191 {
1192 FILE *f;
1193
1194 f = ftp_request(url, "STAT", us, ftp_get_proxy(url, flags), flags);
1195 if (f == NULL)
1196 return (-1);
1197 /*
1198 * When op is "STAT", ftp_request() will return either NULL or
1199 * (FILE *)1, never a valid FILE *, so we mustn't fclose(f) before
1200 * returning, as it would cause a segfault.
1201 */
1202 return (0);
1203 }
1204
1205 /*
1206 * List a directory
1207 */
1208 struct url_ent *
fetchListFTP(struct url * url __unused,const char * flags __unused)1209 fetchListFTP(struct url *url __unused, const char *flags __unused)
1210 {
1211 warnx("fetchListFTP(): not implemented");
1212 return (NULL);
1213 }
1214