xref: /netbsd-src/libexec/ftpd/cmds.c (revision 1ca5c1b28139779176bd5c13ad7c5f25c0bcd5f8)
1 /*	$NetBSD: cmds.c,v 1.14 2002/01/17 05:21:47 itojun Exp $	*/
2 
3 /*
4  * Copyright (c) 1999-2001 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Luke Mewburn.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994
41  *	The Regents of the University of California.  All rights reserved.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  * 3. All advertising materials mentioning features or use of this software
52  *    must display the following acknowledgement:
53  *	This product includes software developed by the University of
54  *	California, Berkeley and its contributors.
55  * 4. Neither the name of the University nor the names of its contributors
56  *    may be used to endorse or promote products derived from this software
57  *    without specific prior written permission.
58  *
59  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
60  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
61  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
62  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
63  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
64  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
65  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
66  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
67  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
68  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
69  * SUCH DAMAGE.
70  */
71 
72 /*
73  * Copyright (C) 1997 and 1998 WIDE Project.
74  * All rights reserved.
75  *
76  * Redistribution and use in source and binary forms, with or without
77  * modification, are permitted provided that the following conditions
78  * are met:
79  * 1. Redistributions of source code must retain the above copyright
80  *    notice, this list of conditions and the following disclaimer.
81  * 2. Redistributions in binary form must reproduce the above copyright
82  *    notice, this list of conditions and the following disclaimer in the
83  *    documentation and/or other materials provided with the distribution.
84  * 3. Neither the name of the project nor the names of its contributors
85  *    may be used to endorse or promote products derived from this software
86  *    without specific prior written permission.
87  *
88  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
89  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
90  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
91  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
92  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
93  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
94  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
95  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
96  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
97  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
98  * SUCH DAMAGE.
99  */
100 
101 
102 #include <sys/cdefs.h>
103 #ifndef lint
104 __RCSID("$NetBSD: cmds.c,v 1.14 2002/01/17 05:21:47 itojun Exp $");
105 #endif /* not lint */
106 
107 #include <sys/param.h>
108 #include <sys/stat.h>
109 
110 #include <arpa/ftp.h>
111 
112 #include <dirent.h>
113 #include <errno.h>
114 #include <setjmp.h>
115 #include <stdio.h>
116 #include <stdlib.h>
117 #include <string.h>
118 #include <tzfile.h>
119 #include <unistd.h>
120 
121 #ifdef KERBEROS5
122 #include <krb5/krb5.h>
123 #endif
124 
125 #include "extern.h"
126 
127 typedef struct {
128 	const char	*path;		/* full pathname */
129 	const char	*display;	/* name to display */
130 	struct stat	*stat;		/* stat of path */
131 	struct stat	*pdirstat;	/* stat of path's parent dir */
132 	int		 iscurdir;	/* nonzero if name is the current dir */
133 } factelem;
134 
135 static void	ack(const char *);
136 static void	base64_encode(const char *, size_t, char *, int);
137 static void	fact_type(const char *, FILE *, factelem *);
138 static void	fact_size(const char *, FILE *, factelem *);
139 static void	fact_modify(const char *, FILE *, factelem *);
140 static void	fact_perm(const char *, FILE *, factelem *);
141 static void	fact_unique(const char *, FILE *, factelem *);
142 static int	matchgroup(gid_t);
143 static void	mlsname(FILE *, factelem *);
144 static void	replydirname(const char *, const char *);
145 
146 struct ftpfact {
147 	const char	 *name;		/* name of fact */
148 	int		  enabled;	/* if fact is enabled */
149 	void		(*display)(const char *, FILE *, factelem *);
150 					/* function to display fact */
151 };
152 
153 struct ftpfact facttab[] = {
154 	{ "Type",	1, fact_type },
155 #define	FACT_TYPE 0
156 	{ "Size",	1, fact_size },
157 	{ "Modify",	1, fact_modify },
158 	{ "Perm",	1, fact_perm },
159 	{ "Unique",	1, fact_unique },
160 	/* "Create" */
161 	/* "Lang" */
162 	/* "Media-Type" */
163 	/* "CharSet" */
164 };
165 
166 #define FACTTABSIZE	(sizeof(facttab) / sizeof(struct ftpfact))
167 
168 
169 void
170 cwd(const char *path)
171 {
172 
173 	if (chdir(path) < 0)
174 		perror_reply(550, path);
175 	else {
176 		show_chdir_messages(250);
177 		ack("CWD");
178 	}
179 }
180 
181 void
182 delete(const char *name)
183 {
184 	char *p = NULL;
185 
186 	if (remove(name) < 0) {
187 		p = strerror(errno);
188 		perror_reply(550, name);
189 	} else
190 		ack("DELE");
191 	logxfer("delete", -1, name, NULL, NULL, p);
192 }
193 
194 void
195 feat(void)
196 {
197 	int i;
198 
199 	reply(-211, "Features supported");
200 	cprintf(stdout, " MDTM\r\n");
201 	cprintf(stdout, " MLST ");
202 	for (i = 0; i < FACTTABSIZE; i++)
203 		cprintf(stdout, "%s%s;", facttab[i].name,
204 		    facttab[i].enabled ? "*" : "");
205 	cprintf(stdout, "\r\n");
206 	cprintf(stdout, " REST STREAM\r\n");
207 	cprintf(stdout, " SIZE\r\n");
208 	cprintf(stdout, " TVFS\r\n");
209 	reply(211,  "End");
210 }
211 
212 void
213 makedir(const char *name)
214 {
215 	char *p = NULL;
216 
217 	if (mkdir(name, 0777) < 0) {
218 		p = strerror(errno);
219 		perror_reply(550, name);
220 	} else
221 		replydirname(name, "directory created.");
222 	logxfer("mkdir", -1, name, NULL, NULL, p);
223 }
224 
225 void
226 mlsd(const char *path)
227 {
228 	struct dirent	*dp;
229 	struct stat	 sb, pdirstat;
230 	factelem f;
231 	FILE	*dout;
232 	DIR	*dirp;
233 	char	name[MAXPATHLEN];
234 	int	hastypefact;
235 
236 	hastypefact = facttab[FACT_TYPE].enabled;
237 	if (path == NULL)
238 		path = ".";
239 	if (stat(path, &pdirstat) == -1) {
240  mlsdperror:
241 		perror_reply(550, path);
242 		return;
243 	}
244 	if (! S_ISDIR(pdirstat.st_mode)) {
245 		errno = ENOTDIR;
246 		perror_reply(501, path);
247 		return;
248 	}
249 	dout = dataconn("MLSD", (off_t)-1, "w");
250 	if (dout == NULL)
251 		return;
252 
253 	if ((dirp = opendir(path)) == NULL)
254 		goto mlsdperror;
255 	f.stat = &sb;
256 	while ((dp = readdir(dirp)) != NULL) {
257 		snprintf(name, sizeof(name), "%s/%s", path, dp->d_name);
258 		if (ISDOTDIR(dp->d_name)) {	/* special case curdir: */
259 			if (! hastypefact)
260 				continue;
261 			f.pdirstat = NULL;	/*   require stat of parent */
262 			f.display = path;	/*   set name to real name */
263 			f.iscurdir = 1;		/*   flag name is curdir */
264 		} else {
265 			if (ISDOTDOTDIR(dp->d_name)) {
266 				if (! hastypefact)
267 					continue;
268 				f.pdirstat = NULL;
269 			} else
270 				f.pdirstat = &pdirstat;	/* cache parent stat */
271 			f.display = dp->d_name;
272 			f.iscurdir = 0;
273 		}
274 		if (stat(name, &sb) == -1)
275 			continue;
276 		f.path = name;
277 		mlsname(dout, &f);
278 	}
279 	(void)closedir(dirp);
280 
281 	if (ferror(dout) != 0)
282 		perror_reply(550, "Data connection");
283 	else
284 		reply(226, "MLSD complete.");
285 	closedataconn(dout);
286 	total_xfers_out++;
287 	total_xfers++;
288 }
289 
290 void
291 mlst(const char *path)
292 {
293 	struct stat sb;
294 	factelem f;
295 
296 	if (path == NULL)
297 		path = ".";
298 	if (stat(path, &sb) == -1) {
299 		perror_reply(550, path);
300 		return;
301 	}
302 	reply(-250, "MLST %s", path);
303 	f.path = path;
304 	f.display = path;
305 	f.stat = &sb;
306 	f.pdirstat = NULL;
307 	f.iscurdir = 0;
308 	CPUTC(' ', stdout);
309 	mlsname(stdout, &f);
310 	reply(250, "End");
311 }
312 
313 
314 void
315 opts(const char *command)
316 {
317 	struct tab *c;
318 	char *ep;
319 
320 	if ((ep = strchr(command, ' ')) != NULL)
321 		*ep++ = '\0';
322 	c = lookup(cmdtab, command);
323 	if (c == NULL) {
324 		reply(502, "Unknown command %s.", command);
325 		return;
326 	}
327 	if (! CMD_IMPLEMENTED(c)) {
328 		reply(501, "%s command not implemented.", c->name);
329 		return;
330 	}
331 	if (! CMD_HAS_OPTIONS(c)) {
332 		reply(501, "%s command does not support persistent options.",
333 		    c->name);
334 		return;
335 	}
336 
337 			/* special case: MLST */
338 	if (strcasecmp(command, "MLST") == 0) {
339 		int	 enabled[FACTTABSIZE];
340 		int	 i, onedone;
341 		size_t	 len;
342 		char	*p;
343 
344 		for (i = 0; i < sizeof(enabled) / sizeof(int); i++)
345 			enabled[i] = 0;
346 		if (ep == NULL || *ep == '\0')
347 			goto displaymlstopts;
348 
349 				/* don't like spaces, and need trailing ; */
350 		len = strlen(ep);
351 		if (strchr(ep, ' ') != NULL || ep[len - 1] != ';') {
352  badmlstopt:
353 			reply(501, "Invalid MLST options");
354 			return;
355 		}
356 		ep[len - 1] = '\0';
357 		while ((p = strsep(&ep, ";")) != NULL) {
358 			if (*p == '\0')
359 				goto badmlstopt;
360 			for (i = 0; i < FACTTABSIZE; i++)
361 				if (strcasecmp(p, facttab[i].name) == 0) {
362 					enabled[i] = 1;
363 					break;
364 				}
365 		}
366 
367  displaymlstopts:
368 		for (i = 0; i < FACTTABSIZE; i++)
369 			facttab[i].enabled = enabled[i];
370 		cprintf(stdout, "200 MLST OPTS");
371 		for (i = onedone = 0; i < FACTTABSIZE; i++) {
372 			if (facttab[i].enabled) {
373 				cprintf(stdout, "%s%s;", onedone ? "" : " ",
374 				    facttab[i].name);
375 				onedone++;
376 			}
377 		}
378 		cprintf(stdout, "\r\n");
379 		fflush(stdout);
380 		return;
381 	}
382 
383 			/* default cases */
384 	if (ep != NULL && *ep != '\0')
385 		REASSIGN(c->options, xstrdup(ep));
386 	if (c->options != NULL)
387 		reply(200, "Options for %s are '%s'.", c->name,
388 		    c->options);
389 	else
390 		reply(200, "No options defined for %s.", c->name);
391 }
392 
393 void
394 pwd(void)
395 {
396 	char path[MAXPATHLEN];
397 
398 	if (getcwd(path, sizeof(path) - 1) == NULL)
399 		reply(550, "Can't get the current directory: %s.",
400 		    strerror(errno));
401 	else
402 		replydirname(path, "is the current directory.");
403 }
404 
405 void
406 removedir(const char *name)
407 {
408 	char *p = NULL;
409 
410 	if (rmdir(name) < 0) {
411 		p = strerror(errno);
412 		perror_reply(550, name);
413 	} else
414 		ack("RMD");
415 	logxfer("rmdir", -1, name, NULL, NULL, p);
416 }
417 
418 char *
419 renamefrom(const char *name)
420 {
421 	struct stat st;
422 
423 	if (stat(name, &st) < 0) {
424 		perror_reply(550, name);
425 		return (NULL);
426 	}
427 	reply(350, "File exists, ready for destination name");
428 	return (xstrdup(name));
429 }
430 
431 void
432 renamecmd(const char *from, const char *to)
433 {
434 	char *p = NULL;
435 
436 	if (rename(from, to) < 0) {
437 		p = strerror(errno);
438 		perror_reply(550, "rename");
439 	} else
440 		ack("RNTO");
441 	logxfer("rename", -1, from, to, NULL, p);
442 }
443 
444 void
445 sizecmd(const char *filename)
446 {
447 	switch (type) {
448 	case TYPE_L:
449 	case TYPE_I:
450 	    {
451 		struct stat stbuf;
452 		if (stat(filename, &stbuf) < 0 || !S_ISREG(stbuf.st_mode))
453 			reply(550, "%s: not a plain file.", filename);
454 		else
455 			reply(213, ULLF, (ULLT)stbuf.st_size);
456 		break;
457 	    }
458 	case TYPE_A:
459 	    {
460 		FILE *fin;
461 		int c;
462 		off_t count;
463 		struct stat stbuf;
464 		fin = fopen(filename, "r");
465 		if (fin == NULL) {
466 			perror_reply(550, filename);
467 			return;
468 		}
469 		if (fstat(fileno(fin), &stbuf) < 0 || !S_ISREG(stbuf.st_mode)) {
470 			reply(550, "%s: not a plain file.", filename);
471 			(void) fclose(fin);
472 			return;
473 		}
474 		if (stbuf.st_size > 10240) {
475 			reply(550, "%s: file too large for SIZE.", filename);
476 			(void) fclose(fin);
477 			return;
478 		}
479 
480 		count = 0;
481 		while((c = getc(fin)) != EOF) {
482 			if (c == '\n')	/* will get expanded to \r\n */
483 				count++;
484 			count++;
485 		}
486 		(void) fclose(fin);
487 
488 		reply(213, LLF, (LLT)count);
489 		break;
490 	    }
491 	default:
492 		reply(504, "SIZE not implemented for Type %c.", "?AEIL"[type]);
493 	}
494 }
495 
496 void
497 statfilecmd(const char *filename)
498 {
499 	FILE *fin;
500 	int c;
501 	char *argv[] = { INTERNAL_LS, "-lgA", "", NULL };
502 
503 	argv[2] = (char *)filename;
504 	fin = ftpd_popen(argv, "r", STDOUT_FILENO);
505 	reply(-211, "status of %s:", filename);
506 /* XXX: use fgetln() or fparseln() here? */
507 	while ((c = getc(fin)) != EOF) {
508 		if (c == '\n') {
509 			if (ferror(stdout)){
510 				perror_reply(421, "control connection");
511 				(void) ftpd_pclose(fin);
512 				dologout(1);
513 				/* NOTREACHED */
514 			}
515 			if (ferror(fin)) {
516 				perror_reply(551, filename);
517 				(void) ftpd_pclose(fin);
518 				return;
519 			}
520 			CPUTC('\r', stdout);
521 		}
522 		CPUTC(c, stdout);
523 	}
524 	(void) ftpd_pclose(fin);
525 	reply(211, "End of Status");
526 }
527 
528 /* -- */
529 
530 static void
531 ack(const char *s)
532 {
533 
534 	reply(250, "%s command successful.", s);
535 }
536 
537 /*
538  * Encode len bytes starting at clear using base64 encoding into encoded,
539  * which should be at least ((len + 2) * 4 / 3 + 1) in size.
540  * If nulterm is non-zero, terminate with \0 otherwise pad to 3 byte boundary
541  * with `='.
542  */
543 static void
544 base64_encode(const char *clear, size_t len, char *encoded, int nulterm)
545 {
546 	static const char base64[] =
547 	    "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
548 	const char *c;
549 	char	*e, termchar;
550 	int	 i;
551 
552 			/* determine whether to pad with '=' or NUL terminate */
553 	termchar = nulterm ? '\0' : '=';
554 	c = clear;
555 	e = encoded;
556 			/* convert all but last 2 bytes */
557 	for (i = len; i > 2; i -= 3, c += 3) {
558 		*e++ = base64[(c[0] >> 2) & 0x3f];
559 		*e++ = base64[((c[0] << 4) & 0x30) | ((c[1] >> 4) & 0x0f)];
560 		*e++ = base64[((c[1] << 2) & 0x3c) | ((c[2] >> 6) & 0x03)];
561 		*e++ = base64[(c[2]) & 0x3f];
562 	}
563 			/* handle slop at end */
564 	if (i > 0) {
565 		*e++ = base64[(c[0] >> 2) & 0x3f];
566 		*e++ = base64[((c[0] << 4) & 0x30) |
567 		     (i > 1 ? ((c[1] >> 4) & 0x0f) : 0)];
568 		*e++ = (i > 1) ? base64[(c[1] << 2) & 0x3c] : termchar;
569 		*e++ = termchar;
570 	}
571 	*e = '\0';
572 }
573 
574 static void
575 fact_modify(const char *fact, FILE *fd, factelem *fe)
576 {
577 	struct tm *t;
578 
579 	t = gmtime(&(fe->stat->st_mtime));
580 	cprintf(fd, "%s=%04d%02d%02d%02d%02d%02d;", fact,
581 	    TM_YEAR_BASE + t->tm_year,
582 	    t->tm_mon+1, t->tm_mday,
583 	    t->tm_hour, t->tm_min, t->tm_sec);
584 }
585 
586 static void
587 fact_perm(const char *fact, FILE *fd, factelem *fe)
588 {
589 	int		rok, wok, xok, pdirwok;
590 	struct stat	*pdir;
591 
592 	if (fe->stat->st_uid == geteuid()) {
593 		rok = ((fe->stat->st_mode & S_IRUSR) != 0);
594 		wok = ((fe->stat->st_mode & S_IWUSR) != 0);
595 		xok = ((fe->stat->st_mode & S_IXUSR) != 0);
596 	} else if (matchgroup(fe->stat->st_gid)) {
597 		rok = ((fe->stat->st_mode & S_IRGRP) != 0);
598 		wok = ((fe->stat->st_mode & S_IWGRP) != 0);
599 		xok = ((fe->stat->st_mode & S_IXGRP) != 0);
600 	} else {
601 		rok = ((fe->stat->st_mode & S_IROTH) != 0);
602 		wok = ((fe->stat->st_mode & S_IWOTH) != 0);
603 		xok = ((fe->stat->st_mode & S_IXOTH) != 0);
604 	}
605 
606 	cprintf(fd, "%s=", fact);
607 
608 			/*
609 			 * if parent info not provided, look it up, but
610 			 * only if the current class has modify rights,
611 			 * since we only need this info in such a case.
612 			 */
613 	pdir = fe->pdirstat;
614 	if (pdir == NULL && CURCLASS_FLAGS_ISSET(modify)) {
615 		size_t		len;
616 		char		realdir[MAXPATHLEN], *p;
617 		struct stat	dir;
618 
619 		len = strlcpy(realdir, fe->path, sizeof(realdir));
620 		if (len < sizeof(realdir) - 4) {
621 			if (S_ISDIR(fe->stat->st_mode))
622 				strlcat(realdir, "/..", sizeof(realdir));
623 			else {
624 					/* if has a /, move back to it */
625 					/* otherwise use '..' */
626 				if ((p = strrchr(realdir, '/')) != NULL) {
627 					if (p == realdir)
628 						p++;
629 					*p = '\0';
630 				} else
631 					strlcpy(realdir, "..", sizeof(realdir));
632 			}
633 			if (stat(realdir, &dir) == 0)
634 				pdir = &dir;
635 		}
636 	}
637 	pdirwok = 0;
638 	if (pdir != NULL) {
639 		if (pdir->st_uid == geteuid())
640 			pdirwok = ((pdir->st_mode & S_IWUSR) != 0);
641 		else if (matchgroup(pdir->st_gid))
642 			pdirwok = ((pdir->st_mode & S_IWGRP) != 0);
643 		else
644 			pdirwok = ((pdir->st_mode & S_IWOTH) != 0);
645 	}
646 
647 			/* 'a': can APPE to file */
648 	if (wok && CURCLASS_FLAGS_ISSET(upload) && S_ISREG(fe->stat->st_mode))
649 		CPUTC('a', fd);
650 
651 			/* 'c': can create or append to files in directory */
652 	if (wok && CURCLASS_FLAGS_ISSET(modify) && S_ISDIR(fe->stat->st_mode))
653 		CPUTC('c', fd);
654 
655 			/* 'd': can delete file or directory */
656 	if (pdirwok && CURCLASS_FLAGS_ISSET(modify)) {
657 		int candel;
658 
659 		candel = 1;
660 		if (S_ISDIR(fe->stat->st_mode)) {
661 			DIR *dirp;
662 			struct dirent *dp;
663 
664 			if ((dirp = opendir(fe->display)) == NULL)
665 				candel = 0;
666 			else {
667 				while ((dp = readdir(dirp)) != NULL) {
668 					if (ISDOTDIR(dp->d_name) ||
669 					    ISDOTDOTDIR(dp->d_name))
670 						continue;
671 					candel = 0;
672 					break;
673 				}
674 				closedir(dirp);
675 			}
676 		}
677 		if (candel)
678 			CPUTC('d', fd);
679 	}
680 
681 			/* 'e': can enter directory */
682 	if (xok && S_ISDIR(fe->stat->st_mode))
683 		CPUTC('e', fd);
684 
685 			/* 'f': can rename file or directory */
686 	if (pdirwok && CURCLASS_FLAGS_ISSET(modify))
687 		CPUTC('f', fd);
688 
689 			/* 'l': can list directory */
690 	if (rok && xok && S_ISDIR(fe->stat->st_mode))
691 		CPUTC('l', fd);
692 
693 			/* 'm': can create directory */
694 	if (wok && CURCLASS_FLAGS_ISSET(modify) && S_ISDIR(fe->stat->st_mode))
695 		CPUTC('m', fd);
696 
697 			/* 'p': can remove files in directory */
698 	if (wok && CURCLASS_FLAGS_ISSET(modify) && S_ISDIR(fe->stat->st_mode))
699 		CPUTC('p', fd);
700 
701 			/* 'r': can RETR file */
702 	if (rok && S_ISREG(fe->stat->st_mode))
703 		CPUTC('r', fd);
704 
705 			/* 'w': can STOR file */
706 	if (wok && CURCLASS_FLAGS_ISSET(upload) && S_ISREG(fe->stat->st_mode))
707 		CPUTC('w', fd);
708 
709 	CPUTC(';', fd);
710 }
711 
712 static void
713 fact_size(const char *fact, FILE *fd, factelem *fe)
714 {
715 
716 	if (S_ISREG(fe->stat->st_mode))
717 		cprintf(fd, "%s=" LLF ";", fact, (LLT)fe->stat->st_size);
718 }
719 
720 static void
721 fact_type(const char *fact, FILE *fd, factelem *fe)
722 {
723 
724 	cprintf(fd, "%s=", fact);
725 	switch (fe->stat->st_mode & S_IFMT) {
726 	case S_IFDIR:
727 		if (fe->iscurdir || ISDOTDIR(fe->display))
728 			cprintf(fd, "cdir");
729 		else if (ISDOTDOTDIR(fe->display))
730 			cprintf(fd, "pdir");
731 		else
732 			cprintf(fd, "dir");
733 		break;
734 	case S_IFREG:
735 		cprintf(fd, "file");
736 		break;
737 	case S_IFIFO:
738 		cprintf(fd, "OS.unix=fifo");
739 		break;
740 	case S_IFLNK:		/* XXX: probably a NO-OP with stat() */
741 		cprintf(fd, "OS.unix=slink");
742 		break;
743 	case S_IFSOCK:
744 		cprintf(fd, "OS.unix=socket");
745 		break;
746 	case S_IFBLK:
747 	case S_IFCHR:
748 		cprintf(fd, "OS.unix=%s-%d/%d",
749 		    S_ISBLK(fe->stat->st_mode) ? "blk" : "chr",
750 		    major(fe->stat->st_rdev), minor(fe->stat->st_rdev));
751 		break;
752 	default:
753 		cprintf(fd, "OS.unix=UNKNOWN(0%o)", fe->stat->st_mode & S_IFMT);
754 		break;
755 	}
756 	CPUTC(';', fd);
757 }
758 
759 static void
760 fact_unique(const char *fact, FILE *fd, factelem *fe)
761 {
762 	char obuf[(sizeof(dev_t) + sizeof(ino_t) + 2) * 4 / 3 + 2];
763 	char tbuf[sizeof(dev_t) + sizeof(ino_t)];
764 
765 	memcpy(tbuf,
766 	    (char *)&(fe->stat->st_dev), sizeof(dev_t));
767 	memcpy(tbuf + sizeof(dev_t),
768 	    (char *)&(fe->stat->st_ino), sizeof(ino_t));
769 	base64_encode(tbuf, sizeof(dev_t) + sizeof(ino_t), obuf, 1);
770 	cprintf(fd, "%s=%s;", fact, obuf);
771 }
772 
773 static int
774 matchgroup(gid_t gid)
775 {
776 	int	i;
777 
778 	for (i = 0; i < gidcount; i++)
779 		if (gid == gidlist[i])
780 			return(1);
781 	return (0);
782 }
783 
784 static void
785 mlsname(FILE *fp, factelem *fe)
786 {
787 	int i;
788 
789 	for (i = 0; i < FACTTABSIZE; i++) {
790 		if (facttab[i].enabled)
791 			(facttab[i].display)(facttab[i].name, fp, fe);
792 	}
793 	cprintf(fp, " %s\r\n", fe->display);
794 }
795 
796 static void
797 replydirname(const char *name, const char *message)
798 {
799 	char *p, *ep;
800 	char npath[MAXPATHLEN * 2];
801 
802 	p = npath;
803 	ep = &npath[sizeof(npath) - 1];
804 	while (*name) {
805 		if (*name == '"') {
806 			if (ep - p < 2)
807 				break;
808 			*p++ = *name++;
809 			*p++ = '"';
810 		} else {
811 			if (ep - p < 1)
812 				break;
813 			*p++ = *name++;
814 		}
815 	}
816 	*p = '\0';
817 	reply(257, "\"%s\" %s", npath, message);
818 }
819