ftp.c revision 63336 
1/*-
2 * Copyright (c) 1998 Dag-Erling Co�dan Sm�rgrav
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer
10 *    in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 *    derived from this software without specific prior written permission
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * $FreeBSD: head/lib/libfetch/ftp.c 63336 2000-07-17 21:00:49Z des $
29 */
30
31/*
32 * Portions of this code were taken from or based on ftpio.c:
33 *
34 * ----------------------------------------------------------------------------
35 * "THE BEER-WARE LICENSE" (Revision 42):
36 * <phk@login.dknet.dk> wrote this file.  As long as you retain this notice you
37 * can do whatever you want with this stuff. If we meet some day, and you think
38 * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
39 * ----------------------------------------------------------------------------
40 *
41 * Major Changelog:
42 *
43 * Dag-Erling Co�dan Sm�rgrav
44 * 9 Jun 1998
45 *
46 * Incorporated into libfetch
47 *
48 * Jordan K. Hubbard
49 * 17 Jan 1996
50 *
51 * Turned inside out. Now returns xfers as new file ids, not as a special
52 * `state' of FTP_t
53 *
54 * $ftpioId: ftpio.c,v 1.30 1998/04/11 07:28:53 phk Exp $
55 *
56 */
57
58#include <sys/param.h>
59#include <sys/socket.h>
60#include <netinet/in.h>
61
62#include <ctype.h>
63#include <errno.h>
64#include <netdb.h>
65#include <stdarg.h>
66#include <stdio.h>
67#include <stdlib.h>
68#include <string.h>
69#include <time.h>
70#include <unistd.h>
71
72#include "fetch.h"
73#include "common.h"
74#include "ftperr.h"
75
76#define FTP_ANONYMOUS_USER	"ftp"
77#define FTP_ANONYMOUS_PASSWORD	"ftp"
78#define FTP_DEFAULT_PORT 21
79
80#define FTP_OPEN_DATA_CONNECTION	150
81#define FTP_OK				200
82#define FTP_FILE_STATUS			213
83#define FTP_SERVICE_READY		220
84#define FTP_PASSIVE_MODE		227
85#define FTP_LPASSIVE_MODE		228
86#define FTP_EPASSIVE_MODE		229
87#define FTP_LOGGED_IN			230
88#define FTP_FILE_ACTION_OK		250
89#define FTP_NEED_PASSWORD		331
90#define FTP_NEED_ACCOUNT		332
91#define FTP_FILE_OK			350
92#define FTP_SYNTAX_ERROR		500
93#define FTP_PROTOCOL_ERROR		999
94
95static struct url cached_host;
96static int cached_socket;
97
98static char *last_reply;
99static size_t lr_size, lr_length;
100static int last_code;
101
102#define isftpreply(foo) (isdigit(foo[0]) && isdigit(foo[1]) \
103			 && isdigit(foo[2]) \
104                         && (foo[3] == ' ' || foo[3] == '\0'))
105#define isftpinfo(foo) (isdigit(foo[0]) && isdigit(foo[1]) \
106			&& isdigit(foo[2]) && foo[3] == '-')
107
108/* translate IPv4 mapped IPv6 address to IPv4 address */
109static void
110unmappedaddr(struct sockaddr_in6 *sin6)
111{
112    struct sockaddr_in *sin4;
113    u_int32_t addr;
114    int port;
115
116    if (sin6->sin6_family != AF_INET6 ||
117	!IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr))
118	return;
119    sin4 = (struct sockaddr_in *)sin6;
120    addr = *(u_int32_t *)&sin6->sin6_addr.s6_addr[12];
121    port = sin6->sin6_port;
122    memset(sin4, 0, sizeof(struct sockaddr_in));
123    sin4->sin_addr.s_addr = addr;
124    sin4->sin_port = port;
125    sin4->sin_family = AF_INET;
126    sin4->sin_len = sizeof(struct sockaddr_in);
127}
128
129/*
130 * Get server response
131 */
132static int
133_ftp_chkerr(int cd)
134{
135    if (_fetch_getln(cd, &last_reply, &lr_size, &lr_length) == -1) {
136	_fetch_syserr();
137	return -1;
138    }
139    if (isftpinfo(last_reply)) {
140	while (!isftpreply(last_reply)) {
141	    if (_fetch_getln(cd, &last_reply, &lr_size, &lr_length) == -1) {
142		_fetch_syserr();
143		return -1;
144	    }
145	}
146    }
147
148    while (lr_length && isspace(last_reply[lr_length-1]))
149	lr_length--;
150    last_reply[lr_length] = 0;
151
152    if (!isftpreply(last_reply)) {
153	_ftp_seterr(FTP_PROTOCOL_ERROR);
154	return -1;
155    }
156
157    last_code = (last_reply[0] - '0') * 100
158	+ (last_reply[1] - '0') * 10
159	+ (last_reply[2] - '0');
160
161    return last_code;
162}
163
164/*
165 * Send a command and check reply
166 */
167static int
168_ftp_cmd(int cd, char *fmt, ...)
169{
170    va_list ap;
171    size_t len;
172    char *msg;
173    int r;
174
175    va_start(ap, fmt);
176    len = vasprintf(&msg, fmt, ap);
177    va_end(ap);
178
179    if (msg == NULL) {
180	errno = ENOMEM;
181	_fetch_syserr();
182	return -1;
183    }
184
185    r = _fetch_putln(cd, msg, len);
186    free(msg);
187
188    if (r == -1) {
189	_fetch_syserr();
190	return -1;
191    }
192
193    return _ftp_chkerr(cd);
194}
195
196/*
197 * Transfer file
198 */
199static FILE *
200_ftp_transfer(int cd, char *oper, char *file,
201	      char *mode, off_t offset, char *flags)
202{
203    struct sockaddr_storage sin;
204    struct sockaddr_in6 *sin6;
205    struct sockaddr_in *sin4;
206    int pasv, high, verbose;
207    int e, sd = -1;
208    socklen_t l;
209    char *s;
210    FILE *df;
211
212    /* check flags */
213    pasv = (flags && strchr(flags, 'p'));
214    high = (flags && strchr(flags, 'h'));
215    verbose = (flags && strchr(flags, 'v'));
216
217    /* passive mode */
218    if (!pasv && (s = getenv("FTP_PASSIVE_MODE")) != NULL)
219	pasv = (strncasecmp(s, "no", 2) != 0);
220
221    /* change directory */
222    if (((s = strrchr(file, '/')) != NULL) && (s != file)) {
223	*s = 0;
224	if (verbose)
225	    _fetch_info("changing directory to %s", file);
226	if ((e = _ftp_cmd(cd, "CWD %s", file)) != FTP_FILE_ACTION_OK) {
227	    *s = '/';
228	    if (e != -1)
229		_ftp_seterr(e);
230	    return NULL;
231	}
232	*s++ = '/';
233    } else {
234	if (verbose)
235	    _fetch_info("changing directory to /");
236	if ((e = _ftp_cmd(cd, "CWD /")) != FTP_FILE_ACTION_OK) {
237	    if (e != -1)
238		_ftp_seterr(e);
239	    return NULL;
240	}
241    }
242
243    /* s now points to file name */
244
245    /* find our own address, bind, and listen */
246    l = sizeof sin;
247    if (getsockname(cd, (struct sockaddr *)&sin, &l) == -1)
248	goto sysouch;
249    if (sin.ss_family == AF_INET6)
250	unmappedaddr((struct sockaddr_in6 *)&sin);
251
252    /* open data socket */
253    if ((sd = socket(sin.ss_family, SOCK_STREAM, IPPROTO_TCP)) == -1) {
254	_fetch_syserr();
255	return NULL;
256    }
257
258    if (pasv) {
259	u_char addr[64];
260	char *ln, *p;
261	int i;
262	int port;
263
264	/* send PASV command */
265	if (verbose)
266	    _fetch_info("setting passive mode");
267	switch (sin.ss_family) {
268	case AF_INET:
269	    if ((e = _ftp_cmd(cd, "PASV")) != FTP_PASSIVE_MODE)
270		goto ouch;
271	    break;
272	case AF_INET6:
273	    if ((e = _ftp_cmd(cd, "EPSV")) != FTP_EPASSIVE_MODE) {
274		if (e == -1)
275		    goto ouch;
276		if ((e = _ftp_cmd(cd, "LPSV")) != FTP_LPASSIVE_MODE)
277		    goto ouch;
278	    }
279	    break;
280	default:
281	    e = FTP_PROTOCOL_ERROR; /* XXX: error code should be prepared */
282	    goto ouch;
283	}
284
285	/*
286	 * Find address and port number. The reply to the PASV command
287         * is IMHO the one and only weak point in the FTP protocol.
288	 */
289	ln = last_reply;
290      	switch (e) {
291	case FTP_PASSIVE_MODE:
292	case FTP_LPASSIVE_MODE:
293	    for (p = ln + 3; *p && !isdigit(*p); p++)
294		/* nothing */ ;
295	    if (!*p) {
296		e = FTP_PROTOCOL_ERROR;
297		goto ouch;
298	    }
299	    l = (e == FTP_PASSIVE_MODE ? 6 : 21);
300	    for (i = 0; *p && i < l; i++, p++)
301		addr[i] = strtol(p, &p, 10);
302	    if (i < l) {
303		e = FTP_PROTOCOL_ERROR;
304		goto ouch;
305	    }
306	    break;
307	case FTP_EPASSIVE_MODE:
308	    for (p = ln + 3; *p && *p != '('; p++)
309		/* nothing */ ;
310	    if (!*p) {
311		e = FTP_PROTOCOL_ERROR;
312		goto ouch;
313	    }
314	    ++p;
315	    if (sscanf(p, "%c%c%c%d%c", &addr[0], &addr[1], &addr[2],
316		       &port, &addr[3]) != 5 ||
317		addr[0] != addr[1] ||
318		addr[0] != addr[2] || addr[0] != addr[3]) {
319		e = FTP_PROTOCOL_ERROR;
320		goto ouch;
321	    }
322	    break;
323	}
324
325	/* seek to required offset */
326	if (offset)
327	    if (_ftp_cmd(cd, "REST %lu", (u_long)offset) != FTP_FILE_OK)
328		goto sysouch;
329
330	/* construct sockaddr for data socket */
331	l = sizeof sin;
332	if (getpeername(cd, (struct sockaddr *)&sin, &l) == -1)
333	    goto sysouch;
334	if (sin.ss_family == AF_INET6)
335	    unmappedaddr((struct sockaddr_in6 *)&sin);
336	switch (sin.ss_family) {
337	case AF_INET6:
338	    sin6 = (struct sockaddr_in6 *)&sin;
339	    if (e == FTP_EPASSIVE_MODE)
340		sin6->sin6_port = htons(port);
341	    else {
342		bcopy(addr + 2, (char *)&sin6->sin6_addr, 16);
343		bcopy(addr + 19, (char *)&sin6->sin6_port, 2);
344	    }
345	    break;
346	case AF_INET:
347	    sin4 = (struct sockaddr_in *)&sin;
348	    if (e == FTP_EPASSIVE_MODE)
349		sin4->sin_port = htons(port);
350	    else {
351		bcopy(addr, (char *)&sin4->sin_addr, 4);
352		bcopy(addr + 4, (char *)&sin4->sin_port, 2);
353	    }
354	    break;
355	default:
356	    e = FTP_PROTOCOL_ERROR; /* XXX: error code should be prepared */
357	    break;
358	}
359
360	/* connect to data port */
361	if (verbose)
362	    _fetch_info("opening data connection");
363	if (connect(sd, (struct sockaddr *)&sin, sin.ss_len) == -1)
364	    goto sysouch;
365
366	/* make the server initiate the transfer */
367	if (verbose)
368	    _fetch_info("initiating transfer");
369	e = _ftp_cmd(cd, "%s %s", oper, s);
370	if (e != FTP_OPEN_DATA_CONNECTION)
371	    goto ouch;
372
373    } else {
374	u_int32_t a;
375	u_short p;
376	int arg, d;
377	char *ap;
378	char hname[INET6_ADDRSTRLEN];
379
380	switch (sin.ss_family) {
381	case AF_INET6:
382	    ((struct sockaddr_in6 *)&sin)->sin6_port = 0;
383#ifdef IPV6_PORTRANGE
384	    arg = high ? IPV6_PORTRANGE_HIGH : IPV6_PORTRANGE_DEFAULT;
385	    if (setsockopt(sd, IPPROTO_IPV6, IPV6_PORTRANGE,
386			   (char *)&arg, sizeof(arg)) == -1)
387		goto sysouch;
388#endif
389	    break;
390	case AF_INET:
391	    ((struct sockaddr_in *)&sin)->sin_port = 0;
392	    arg = high ? IP_PORTRANGE_HIGH : IP_PORTRANGE_DEFAULT;
393	    if (setsockopt(sd, IPPROTO_IP, IP_PORTRANGE,
394			   (char *)&arg, sizeof arg) == -1)
395		goto sysouch;
396	    break;
397	}
398	if (verbose)
399	    _fetch_info("binding data socket");
400	if (bind(sd, (struct sockaddr *)&sin, sin.ss_len) == -1)
401	    goto sysouch;
402	if (listen(sd, 1) == -1)
403	    goto sysouch;
404
405	/* find what port we're on and tell the server */
406	if (getsockname(sd, (struct sockaddr *)&sin, &l) == -1)
407	    goto sysouch;
408	switch (sin.ss_family) {
409	case AF_INET:
410	    sin4 = (struct sockaddr_in *)&sin;
411	    a = ntohl(sin4->sin_addr.s_addr);
412	    p = ntohs(sin4->sin_port);
413	    e = _ftp_cmd(cd, "PORT %d,%d,%d,%d,%d,%d",
414			 (a >> 24) & 0xff, (a >> 16) & 0xff,
415			 (a >> 8) & 0xff, a & 0xff,
416			 (p >> 8) & 0xff, p & 0xff);
417	    break;
418	case AF_INET6:
419#define UC(b)	(((int)b)&0xff)
420	    e = -1;
421	    sin6 = (struct sockaddr_in6 *)&sin;
422	    if (getnameinfo((struct sockaddr *)&sin, sin.ss_len,
423			    hname, sizeof(hname),
424			    NULL, 0, NI_NUMERICHOST) == 0) {
425		e = _ftp_cmd(cd, "EPRT |%d|%s|%d|", 2, hname,
426			     htons(sin6->sin6_port));
427		if (e == -1)
428		    goto ouch;
429	    }
430	    if (e != FTP_OK) {
431		ap = (char *)&sin6->sin6_addr;
432		e = _ftp_cmd(cd,
433     "LPRT %d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d",
434			     6, 16,
435			     UC(ap[0]), UC(ap[1]), UC(ap[2]), UC(ap[3]),
436			     UC(ap[4]), UC(ap[5]), UC(ap[6]), UC(ap[7]),
437			     UC(ap[8]), UC(ap[9]), UC(ap[10]), UC(ap[11]),
438			     UC(ap[12]), UC(ap[13]), UC(ap[14]), UC(ap[15]),
439			     2,
440			     (ntohs(sin6->sin6_port) >> 8) & 0xff,
441			     ntohs(sin6->sin6_port)        & 0xff);
442	    }
443	    break;
444	default:
445	    e = FTP_PROTOCOL_ERROR; /* XXX: error code should be prepared */
446	    goto ouch;
447	}
448	if (e != FTP_OK)
449	    goto ouch;
450
451	/* seek to required offset */
452	if (offset)
453	    if (_ftp_cmd(cd, "REST %lu", (u_long)offset) != FTP_FILE_OK)
454		goto sysouch;
455
456	/* make the server initiate the transfer */
457	if (verbose)
458	    _fetch_info("initiating transfer");
459	e = _ftp_cmd(cd, "%s %s", oper, s);
460	if (e != FTP_OPEN_DATA_CONNECTION)
461	    goto ouch;
462
463	/* accept the incoming connection and go to town */
464	if ((d = accept(sd, NULL, NULL)) == -1)
465	    goto sysouch;
466	close(sd);
467	sd = d;
468    }
469
470    if ((df = fdopen(sd, mode)) == NULL)
471	goto sysouch;
472    return df;
473
474sysouch:
475    _fetch_syserr();
476    if (sd >= 0)
477	close(sd);
478    return NULL;
479
480ouch:
481    if (e != -1)
482	_ftp_seterr(e);
483    if (sd >= 0)
484	close(sd);
485    return NULL;
486}
487
488/*
489 * Log on to FTP server
490 */
491static int
492_ftp_connect(char *host, int port, char *user, char *pwd, char *flags)
493{
494    int cd, e, pp = 0, direct, verbose;
495#ifdef INET6
496    int af = AF_UNSPEC;
497#else
498    int af = AF_INET;
499#endif
500    char *p, *q;
501    const char *logname;
502    char localhost[MAXHOSTNAMELEN];
503    char pbuf[MAXHOSTNAMELEN + MAXLOGNAME + 1];
504
505    direct = (flags && strchr(flags, 'd'));
506    verbose = (flags && strchr(flags, 'v'));
507    if ((flags && strchr(flags, '4')))
508	af = AF_INET;
509    else if ((flags && strchr(flags, '6')))
510	af = AF_INET6;
511
512    /* check for proxy */
513    if (!direct && (p = getenv("FTP_PROXY")) != NULL) {
514	char c = 0;
515
516#ifdef INET6
517	if (*p != '[' || (q = strchr(p + 1, ']')) == NULL ||
518	    (*++q != '\0' && *q != ':'))
519#endif
520	    q = strchr(p, ':');
521	if (q != NULL && *q == ':') {
522	    if (strspn(q+1, "0123456789") != strlen(q+1) || strlen(q+1) > 5) {
523		/* XXX we should emit some kind of warning */
524	    }
525	    pp = atoi(q+1);
526	    if (pp < 1 || pp > 65535) {
527		/* XXX we should emit some kind of warning */
528	    }
529	}
530	if (!pp) {
531	    struct servent *se;
532
533	    if ((se = getservbyname("ftp", "tcp")) != NULL)
534		pp = ntohs(se->s_port);
535	    else
536		pp = FTP_DEFAULT_PORT;
537	}
538	if (q) {
539#ifdef INET6
540	    if (q > p && *p == '[' && *(q - 1) == ']') {
541		p++;
542		q--;
543	    }
544#endif
545	    c = *q;
546	    *q = 0;
547	}
548	cd = _fetch_connect(p, pp, af, verbose);
549	if (q)
550	    *q = c;
551    } else {
552	/* no proxy, go straight to target */
553	cd = _fetch_connect(host, port, af, verbose);
554	p = NULL;
555    }
556
557    /* check connection */
558    if (cd == -1) {
559	_fetch_syserr();
560	return NULL;
561    }
562
563    /* expect welcome message */
564    if ((e = _ftp_chkerr(cd)) != FTP_SERVICE_READY)
565	goto fouch;
566
567    /* send user name and password */
568    if (!user || !*user)
569	user = FTP_ANONYMOUS_USER;
570    e = p ? _ftp_cmd(cd, "USER %s@%s@%d", user, host, port)
571	  : _ftp_cmd(cd, "USER %s", user);
572
573    /* did the server request a password? */
574    if (e == FTP_NEED_PASSWORD) {
575	if (!pwd || !*pwd)
576	    pwd = getenv("FTP_PASSWORD");
577	if (!pwd || !*pwd) {
578	    if ((logname = getlogin()) == 0)
579		logname = FTP_ANONYMOUS_PASSWORD;
580	    gethostname(localhost, sizeof localhost);
581	    snprintf(pbuf, sizeof pbuf, "%s@%s", logname, localhost);
582	    pwd = pbuf;
583	}
584	e = _ftp_cmd(cd, "PASS %s", pwd);
585    }
586
587    /* did the server request an account? */
588    if (e == FTP_NEED_ACCOUNT)
589	goto fouch;
590
591    /* we should be done by now */
592    if (e != FTP_LOGGED_IN)
593	goto fouch;
594
595    /* might as well select mode and type at once */
596#ifdef FTP_FORCE_STREAM_MODE
597    if ((e = _ftp_cmd(cd, "MODE S")) != FTP_OK) /* default is S */
598	goto fouch;
599#endif
600    if ((e = _ftp_cmd(cd, "TYPE I")) != FTP_OK) /* default is A */
601	goto fouch;
602
603    /* done */
604    return cd;
605
606fouch:
607    if (e != -1)
608	_ftp_seterr(e);
609    close(cd);
610    return NULL;
611}
612
613/*
614 * Disconnect from server
615 */
616static void
617_ftp_disconnect(int cd)
618{
619    (void)_ftp_cmd(cd, "QUIT");
620    close(cd);
621}
622
623/*
624 * Check if we're already connected
625 */
626static int
627_ftp_isconnected(struct url *url)
628{
629    return (cached_socket
630	    && (strcmp(url->host, cached_host.host) == 0)
631	    && (strcmp(url->user, cached_host.user) == 0)
632	    && (strcmp(url->pwd, cached_host.pwd) == 0)
633	    && (url->port == cached_host.port));
634}
635
636/*
637 * Check the cache, reconnect if no luck
638 */
639static int
640_ftp_cached_connect(struct url *url, char *flags)
641{
642    int e, cd;
643
644    cd = -1;
645
646    /* set default port */
647    if (!url->port) {
648	struct servent *se;
649
650	if ((se = getservbyname("ftp", "tcp")) != NULL)
651	    url->port = ntohs(se->s_port);
652	else
653	    url->port = FTP_DEFAULT_PORT;
654    }
655
656    /* try to use previously cached connection */
657    if (_ftp_isconnected(url)) {
658	e = _ftp_cmd(cached_socket, "NOOP");
659	if (e == FTP_OK || e == FTP_SYNTAX_ERROR)
660	    cd = cached_socket;
661    }
662
663    /* connect to server */
664    if (cd == -1) {
665	cd = _ftp_connect(url->host, url->port, url->user, url->pwd, flags);
666	if (cd == -1)
667	    return -1;
668	if (cached_socket)
669	    _ftp_disconnect(cached_socket);
670	cached_socket = cd;
671	memcpy(&cached_host, url, sizeof *url);
672    }
673
674    return cd;
675}
676
677/*
678 * Get file
679 */
680FILE *
681fetchGetFTP(struct url *url, char *flags)
682{
683    int cd;
684
685    /* connect to server */
686    if ((cd = _ftp_cached_connect(url, flags)) == NULL)
687	return NULL;
688
689    /* initiate the transfer */
690    return _ftp_transfer(cd, "RETR", url->doc, "r", url->offset, flags);
691}
692
693/*
694 * Put file
695 */
696FILE *
697fetchPutFTP(struct url *url, char *flags)
698{
699    int cd;
700
701    /* connect to server */
702    if ((cd = _ftp_cached_connect(url, flags)) == NULL)
703	return NULL;
704
705    /* initiate the transfer */
706    return _ftp_transfer(cd, (flags && strchr(flags, 'a')) ? "APPE" : "STOR",
707			 url->doc, "w", url->offset, flags);
708}
709
710/*
711 * Get file stats
712 */
713int
714fetchStatFTP(struct url *url, struct url_stat *us, char *flags)
715{
716    char *ln, *s;
717    struct tm tm;
718    time_t t;
719    int e, cd;
720
721    us->size = -1;
722    us->atime = us->mtime = 0;
723
724    /* connect to server */
725    if ((cd = _ftp_cached_connect(url, flags)) == NULL)
726	return -1;
727
728    /* change directory */
729    if (((s = strrchr(url->doc, '/')) != NULL) && (s != url->doc)) {
730	*s = 0;
731	if ((e = _ftp_cmd(cd, "CWD %s", url->doc)) != FTP_FILE_ACTION_OK) {
732	    *s = '/';
733	    goto ouch;
734	}
735	*s++ = '/';
736    } else {
737	if ((e = _ftp_cmd(cd, "CWD /")) != FTP_FILE_ACTION_OK)
738	    goto ouch;
739    }
740
741    /* s now points to file name */
742
743    if (_ftp_cmd(cd, "SIZE %s", s) != FTP_FILE_STATUS)
744	goto ouch;
745    for (ln = last_reply + 4; *ln && isspace(*ln); ln++)
746	/* nothing */ ;
747    for (us->size = 0; *ln && isdigit(*ln); ln++)
748	us->size = us->size * 10 + *ln - '0';
749    if (*ln && !isspace(*ln)) {
750	_ftp_seterr(FTP_PROTOCOL_ERROR);
751	return -1;
752    }
753    DEBUG(fprintf(stderr, "size: [\033[1m%lld\033[m]\n", us->size));
754
755    if ((e = _ftp_cmd(cd, "MDTM %s", s)) != FTP_FILE_STATUS)
756	goto ouch;
757    for (ln = last_reply + 4; *ln && isspace(*ln); ln++)
758	/* nothing */ ;
759    e = FTP_PROTOCOL_ERROR;
760    switch (strspn(ln, "0123456789")) {
761    case 14:
762	break;
763    case 15:
764	ln++;
765	ln[0] = '2';
766	ln[1] = '0';
767	break;
768    default:
769	goto ouch;
770    }
771    if (sscanf(ln, "%04d%02d%02d%02d%02d%02d",
772	       &tm.tm_year, &tm.tm_mon, &tm.tm_mday,
773	       &tm.tm_hour, &tm.tm_min, &tm.tm_sec) != 6)
774	goto ouch;
775    tm.tm_mon--;
776    tm.tm_year -= 1900;
777    tm.tm_isdst = -1;
778    t = timegm(&tm);
779    if (t == (time_t)-1)
780	t = time(NULL);
781    us->mtime = t;
782    us->atime = t;
783    DEBUG(fprintf(stderr, "last modified: [\033[1m%04d-%02d-%02d "
784		  "%02d:%02d:%02d\033[m]\n",
785		  tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday,
786		  tm.tm_hour, tm.tm_min, tm.tm_sec));
787    return 0;
788
789ouch:
790    if (e != -1)
791	_ftp_seterr(e);
792    return -1;
793}
794
795/*
796 * List a directory
797 */
798extern void warnx(char *, ...);
799struct url_ent *
800fetchListFTP(struct url *url, char *flags)
801{
802    warnx("fetchListFTP(): not implemented");
803    return NULL;
804}
805