xref: /netbsd-src/usr.sbin/user/user.c (revision 95d875fb90b1458e4f1de6950286ddcd6644bc61)
1 /* $NetBSD: user.c,v 1.10 1999/12/31 21:58:14 agc Exp $ */
2 
3 /*
4  * Copyright (c) 1999 Alistair G. Crooks.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
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. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by Alistair G. Crooks.
17  * 4. The name of the author may not be used to endorse or promote
18  *    products derived from this software without specific prior written
19  *    permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
22  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
23  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
25  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27  * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
31  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 #include <sys/types.h>
34 #include <sys/param.h>
35 #include <sys/stat.h>
36 
37 #include <ctype.h>
38 #include <dirent.h>
39 #include <err.h>
40 #include <fcntl.h>
41 #include <grp.h>
42 #include <pwd.h>
43 #include <stdarg.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <time.h>
48 #include <unistd.h>
49 #include <util.h>
50 
51 #include "defs.h"
52 #include "usermgmt.h"
53 
54 /* this struct describes a uid range */
55 typedef struct range_t {
56 	int	r_from;		/* low uid */
57 	int	r_to;		/* high uid */
58 } range_t;
59 
60 /* this struct encapsulates the user information */
61 typedef struct user_t {
62 	int		u_uid;			/* uid of user */
63 	char		*u_password;		/* encrypted password */
64 	char		*u_comment;		/* comment field */
65 	int		u_homeset;		/* home dir has been set */
66 	char		*u_home;		/* home directory */
67 	char		*u_primgrp;		/* primary group */
68 	int		u_groupc;		/* # of secondary groups */
69 	char		*u_groupv[NGROUPS_MAX];	/* secondary groups */
70 	char		*u_shell;		/* user's shell */
71 	char		*u_basedir;		/* base directory for home */
72 	char		*u_expire;		/* when password will expire */
73 	int		u_inactive;		/* inactive */
74 	int		u_mkdir;		/* make the home directory */
75 	int		u_dupuid;		/* duplicate uids are allowed */
76 	char		*u_skeldir;		/* directory for startup files */
77 	unsigned	u_rsize;		/* size of range array */
78 	unsigned	u_rc;			/* # of ranges */
79 	range_t		*u_rv;			/* the ranges */
80 	unsigned	u_defrc;		/* # of ranges in defaults */
81 	int		u_preserve;		/* preserve uids on deletion */
82 } user_t;
83 
84 #define CONFFILE	"/etc/usermgmt.conf"
85 
86 #ifndef DEF_GROUP
87 #define DEF_GROUP	"users"
88 #endif
89 
90 #ifndef DEF_BASEDIR
91 #define DEF_BASEDIR	"/home"
92 #endif
93 
94 #ifndef DEF_SKELDIR
95 #define DEF_SKELDIR	"/etc/skel"
96 #endif
97 
98 #ifndef DEF_SHELL
99 #define DEF_SHELL	"/bin/csh"
100 #endif
101 
102 #ifndef DEF_COMMENT
103 #define DEF_COMMENT	""
104 #endif
105 
106 #ifndef DEF_LOWUID
107 #define DEF_LOWUID	1000
108 #endif
109 
110 #ifndef DEF_HIGHUID
111 #define DEF_HIGHUID	60000
112 #endif
113 
114 #ifndef DEF_INACTIVE
115 #define DEF_INACTIVE	0
116 #endif
117 
118 #ifndef DEF_EXPIRE
119 #define DEF_EXPIRE	(char *) NULL
120 #endif
121 
122 #ifndef MASTER
123 #define MASTER		"/etc/master.passwd"
124 #endif
125 
126 #ifndef ETCGROUP
127 #define ETCGROUP	"/etc/group"
128 #endif
129 
130 #ifndef WAITSECS
131 #define WAITSECS	10
132 #endif
133 
134 #ifndef NOBODY_UID
135 #define NOBODY_UID	32767
136 #endif
137 
138 /* some useful constants */
139 enum {
140 	MaxShellNameLen = 256,
141 	MaxFileNameLen = MAXPATHLEN,
142 	MaxUserNameLen = 32,
143 	MaxFieldNameLen = 32,
144 	MaxCommandLen = 2048,
145 	MaxEntryLen = 2048,
146 	PasswordLength = 13,
147 
148 	LowGid = DEF_LOWUID,
149 	HighGid = DEF_HIGHUID
150 };
151 
152 /* Full paths of programs used here */
153 #define CHOWN		"/usr/sbin/chown"
154 #define MKDIR		"/bin/mkdir"
155 #define MV		"/bin/mv"
156 #define NOLOGIN		"/sbin/nologin"
157 #define PAX		"/bin/pax"
158 #define RM		"/bin/rm"
159 
160 #define UNSET_EXPIRY	"Null (unset)"
161 
162 static int	verbose;
163 
164 /* if *cpp is non-null, free it, then assign `n' chars of `s' to it */
165 static void
166 memsave(char **cpp, char *s, size_t n)
167 {
168 	if (*cpp != (char *) NULL) {
169 		FREE(*cpp);
170 	}
171 	NEWARRAY(char, *cpp, n + 1, exit(1));
172 	(void) memcpy(*cpp, s, n);
173 	(*cpp)[n] = 0;
174 }
175 
176 /* a replacement for system(3) */
177 static int
178 asystem(char *fmt, ...)
179 {
180 	va_list	vp;
181 	char	buf[MaxCommandLen];
182 	int	ret;
183 
184 	va_start(vp, fmt);
185 	(void) vsnprintf(buf, sizeof(buf), fmt, vp);
186 	va_end(vp);
187 	if (verbose) {
188 		(void) printf("Command: %s\n", buf);
189 	}
190 	if ((ret = system(buf)) != 0) {
191 		warnx("[Warning] can't system `%s'", buf);
192 	}
193 	return ret;
194 }
195 
196 #define NetBSD_1_4_K	104110000
197 
198 #if defined(__NetBSD_Version__) && (__NetBSD_Version__ < NetBSD_1_4_K)
199 /* bounds checking strncpy */
200 static int
201 strlcpy(char *to, char *from, size_t tosize)
202 {
203 	size_t	n;
204 	int	fromsize;
205 
206 	fromsize = strlen(from);
207 	n = MIN(tosize - 1, fromsize);
208 	(void) memcpy(to, from, n);
209 	to[n] = 0;
210 	return fromsize;
211 }
212 #endif
213 
214 #ifdef EXTENSIONS
215 /* return 1 if all of `s' is numeric */
216 static int
217 is_number(char *s)
218 {
219 	for ( ; *s ; s++) {
220 		if (!isdigit(*s)) {
221 			return 0;
222 		}
223 	}
224 	return 1;
225 }
226 #endif
227 
228 /*
229  * check that the effective uid is 0 - called from funcs which will
230  * modify data and config files.
231  */
232 static void
233 checkeuid(void)
234 {
235 	if (geteuid() != 0) {
236 		errx(EXIT_FAILURE, "Program must be run as root");
237 	}
238 }
239 
240 /* copy any dot files into the user's home directory */
241 static int
242 copydotfiles(char *skeldir, int uid, int gid, char *dir)
243 {
244 	struct dirent	*dp;
245 	DIR		*dirp;
246 	int		n;
247 
248 	if ((dirp = opendir(skeldir)) == (DIR *) NULL) {
249 		warn("can't open source . files dir `%s'", skeldir);
250 		return 0;
251 	}
252 	for (n = 0; (dp = readdir(dirp)) != (struct dirent *) NULL && n == 0 ; ) {
253 		if (strcmp(dp->d_name, ".") == 0 ||
254 		    strcmp(dp->d_name, "..") == 0) {
255 			continue;
256 		}
257 		n = 1;
258 	}
259 	(void) closedir(dirp);
260 	if (n == 0) {
261 		warnx("No \"dot\" initialisation files found");
262 	} else {
263 		(void) asystem("cd %s; %s -rw -pe %s . %s",
264 				skeldir, PAX, (verbose) ? "-v" : "", dir);
265 	}
266 	(void) asystem("%s -R -h %d:%d %s", CHOWN, uid, gid, dir);
267 	return n;
268 }
269 
270 /* create a group entry with gid `gid' */
271 static int
272 creategid(char *group, int gid, char *name)
273 {
274 	struct stat	st;
275 	FILE		*from;
276 	FILE		*to;
277 	char		buf[MaxEntryLen];
278 	char		f[MaxFileNameLen];
279 	int		fd;
280 	int		cc;
281 
282 	if ((from = fopen(ETCGROUP, "r")) == (FILE *) NULL) {
283 		warn("can't create gid for %s: can't open %s", name, ETCGROUP);
284 		return 0;
285 	}
286 	if (flock(fileno(from), LOCK_EX | LOCK_NB) < 0) {
287 		warn("can't lock `%s'", ETCGROUP);
288 	}
289 	(void) fstat(fileno(from), &st);
290 	(void) snprintf(f, sizeof(f), "%s.XXXXXX", ETCGROUP);
291 	if ((fd = mkstemp(f)) < 0) {
292 		(void) fclose(from);
293 		warn("can't create gid: mkstemp failed");
294 		return 0;
295 	}
296 	if ((to = fdopen(fd, "w")) == (FILE *) NULL) {
297 		(void) fclose(from);
298 		(void) close(fd);
299 		(void) unlink(f);
300 		warn("can't create gid: fdopen `%s' failed", f);
301 		return 0;
302 	}
303 	while ((cc = fread(buf, sizeof(char), sizeof(buf), from)) > 0) {
304 		if (fwrite(buf, sizeof(char), (unsigned) cc, to) != cc) {
305 			(void) fclose(from);
306 			(void) close(fd);
307 			(void) unlink(f);
308 			warn("can't create gid: short write to `%s'", f);
309 			return 0;
310 		}
311 	}
312 	(void) fprintf(to, "%s:*:%d:%s\n", group, gid, name);
313 	(void) fclose(from);
314 	(void) fclose(to);
315 	if (rename(f, ETCGROUP) < 0) {
316 		warn("can't create gid: can't rename `%s' to `%s'", f, ETCGROUP);
317 		return 0;
318 	}
319 	(void) chmod(ETCGROUP, st.st_mode & 07777);
320 	return 1;
321 }
322 
323 /* modify the group entry with name `group' to be newent */
324 static int
325 modify_gid(char *group, char *newent)
326 {
327 	struct stat	st;
328 	FILE		*from;
329 	FILE		*to;
330 	char		buf[MaxEntryLen];
331 	char		f[MaxFileNameLen];
332 	char		*colon;
333 	int		groupc;
334 	int		entc;
335 	int		fd;
336 	int		cc;
337 
338 	if ((from = fopen(ETCGROUP, "r")) == (FILE *) NULL) {
339 		warn("can't create gid for %s: can't open %s", group, ETCGROUP);
340 		return 0;
341 	}
342 	if (flock(fileno(from), LOCK_EX | LOCK_NB) < 0) {
343 		warn("can't lock `%s'", ETCGROUP);
344 	}
345 	(void) fstat(fileno(from), &st);
346 	(void) snprintf(f, sizeof(f), "%s.XXXXXX", ETCGROUP);
347 	if ((fd = mkstemp(f)) < 0) {
348 		(void) fclose(from);
349 		warn("can't create gid: mkstemp failed");
350 		return 0;
351 	}
352 	if ((to = fdopen(fd, "w")) == (FILE *) NULL) {
353 		(void) fclose(from);
354 		(void) close(fd);
355 		(void) unlink(f);
356 		warn("can't create gid: fdopen `%s' failed", f);
357 		return 0;
358 	}
359 	groupc = strlen(group);
360 	while ((cc = fread(buf, sizeof(char), sizeof(buf), from)) > 0) {
361 		if ((colon = strchr(buf, ':')) == (char *) NULL) {
362 			warn("badly formed entry `%s'", buf);
363 			continue;
364 		}
365 		entc = (int)(colon - buf);
366 		if (entc == groupc && strncmp(group, buf, (unsigned) entc) == 0) {
367 			if (newent == (char *) NULL) {
368 				continue;
369 			} else {
370 				cc = strlen(newent);
371 				(void) strlcpy(buf, newent, sizeof(buf));
372 			}
373 		}
374 		if (fwrite(buf, sizeof(char), (unsigned) cc, to) != cc) {
375 			(void) fclose(from);
376 			(void) close(fd);
377 			(void) unlink(f);
378 			warn("can't create gid: short write to `%s'", f);
379 			return 0;
380 		}
381 	}
382 	(void) fclose(from);
383 	(void) fclose(to);
384 	if (rename(f, ETCGROUP) < 0) {
385 		warn("can't create gid: can't rename `%s' to `%s'", f, ETCGROUP);
386 		return 0;
387 	}
388 	(void) chmod(ETCGROUP, st.st_mode & 07777);
389 	return 1;
390 }
391 
392 /* return 1 if `login' is a valid login name */
393 static int
394 valid_login(char *login)
395 {
396 	char	*cp;
397 
398 	for (cp = login ; *cp ; cp++) {
399 		if (!isalnum(*cp) && *cp != '.' && *cp != '_' && *cp != '-') {
400 			return 0;
401 		}
402 	}
403 	return 1;
404 }
405 
406 /* return 1 if `group' is a valid group name */
407 static int
408 valid_group(char *group)
409 {
410 	char	*cp;
411 
412 	for (cp = group ; *cp ; cp++) {
413 		if (!isalnum(*cp)) {
414 			return 0;
415 		}
416 	}
417 	return 1;
418 }
419 
420 /* find the next gid in the range lo .. hi */
421 static int
422 getnextgid(int *gidp, int lo, int hi)
423 {
424 	for (*gidp = lo ; *gidp < hi ; *gidp += 1) {
425 		if (getgrgid((gid_t)*gidp) == (struct group *) NULL) {
426 			return 1;
427 		}
428 	}
429 	return 0;
430 }
431 
432 #ifdef EXTENSIONS
433 /* save a range of uids */
434 static int
435 save_range(user_t *up, char *cp)
436 {
437 	int	from;
438 	int	to;
439 	int	i;
440 
441 	if (up->u_rsize == 0) {
442 		up->u_rsize = 32;
443 		NEWARRAY(range_t, up->u_rv, up->u_rsize, return(0));
444 	} else if (up->u_rc == up->u_rsize) {
445 		up->u_rsize *= 2;
446 		RENEW(range_t, up->u_rv, up->u_rsize, return(0));
447 	}
448 	if (up->u_rv && sscanf(cp, "%d..%d", &from, &to) == 2) {
449 		for (i = 0 ; i < up->u_rc ; i++) {
450 			if (up->u_rv[i].r_from == from && up->u_rv[i].r_to == to) {
451 				break;
452 			}
453 		}
454 		if (i == up->u_rc) {
455 			up->u_rv[up->u_rc].r_from = from;
456 			up->u_rv[up->u_rc].r_to = to;
457 			up->u_rc += 1;
458 		}
459 	} else {
460 		warnx("Bad range `%s'", cp);
461 		return 0;
462 	}
463 	return 1;
464 }
465 #endif
466 
467 /* set the defaults in the defaults file */
468 static int
469 setdefaults(user_t *up)
470 {
471 	char	template[MaxFileNameLen];
472 	FILE	*fp;
473 	int	ret;
474 	int	fd;
475 	int	i;
476 
477 	(void) snprintf(template, sizeof(template), "%s.XXXXXX", CONFFILE);
478 	if ((fd = mkstemp(template)) < 0) {
479 		warnx("can't mkstemp `%s' for writing", CONFFILE);
480 		return 0;
481 	}
482 	if ((fp = fdopen(fd, "w")) == (FILE *) NULL) {
483 		warn("can't fdopen `%s' for writing", CONFFILE);
484 		return 0;
485 	}
486 	ret = 1;
487 	if (fprintf(fp, "group\t\t%s\n", up->u_primgrp) <= 0 ||
488 	    fprintf(fp, "base_dir\t%s\n", up->u_basedir) <= 0 ||
489 	    fprintf(fp, "skel_dir\t%s\n", up->u_skeldir) <= 0 ||
490 	    fprintf(fp, "shell\t\t%s\n", up->u_shell) <= 0 ||
491 	    fprintf(fp, "inactive\t%d\n", up->u_inactive) <= 0 ||
492 	    fprintf(fp, "expire\t\t%s\n", (up->u_expire == (char *) NULL) ? UNSET_EXPIRY : up->u_expire) <= 0) {
493 		warn("can't write to `%s'", CONFFILE);
494 		ret = 0;
495 	}
496 #ifdef EXTENSIONS
497 	for (i = (up->u_defrc != up->u_rc) ? up->u_defrc : 0 ; i < up->u_rc ; i++) {
498 		if (fprintf(fp, "range\t\t%d..%d\n", up->u_rv[i].r_from, up->u_rv[i].r_to) <= 0) {
499 			warn("can't write to `%s'", CONFFILE);
500 			ret = 0;
501 		}
502 	}
503 #endif
504 	(void) fclose(fp);
505 	if (ret) {
506 		ret = ((rename(template, CONFFILE) == 0) && (chmod(CONFFILE, 0644) == 0));
507 	}
508 	return ret;
509 }
510 
511 /* read the defaults file */
512 static void
513 read_defaults(user_t *up)
514 {
515 	struct stat	st;
516 	size_t		lineno;
517 	size_t		len;
518 	FILE		*fp;
519 	char		*cp;
520 	char		*s;
521 
522 	memsave(&up->u_primgrp, DEF_GROUP, strlen(DEF_GROUP));
523 	memsave(&up->u_basedir, DEF_BASEDIR, strlen(DEF_BASEDIR));
524 	memsave(&up->u_skeldir, DEF_SKELDIR, strlen(DEF_SKELDIR));
525 	memsave(&up->u_shell, DEF_SHELL, strlen(DEF_SHELL));
526 	memsave(&up->u_comment, DEF_COMMENT, strlen(DEF_COMMENT));
527 	up->u_rsize = 16;
528 	NEWARRAY(range_t, up->u_rv, up->u_rsize, exit(1));
529 	up->u_inactive = DEF_INACTIVE;
530 	up->u_expire = DEF_EXPIRE;
531 	if ((fp = fopen(CONFFILE, "r")) == (FILE *) NULL) {
532 		if (stat(CONFFILE, &st) < 0 && !setdefaults(up)) {
533 			warn("can't create `%s' defaults file", CONFFILE);
534 		}
535 		fp = fopen(CONFFILE, "r");
536 	}
537 	if (fp != (FILE *) NULL) {
538 		while ((s = fparseln(fp, &len, &lineno, NULL, 0)) != (char *) NULL) {
539 			if (strncmp(s, "group", 5) == 0) {
540 				for (cp = s + 5 ; *cp && isspace(*cp) ; cp++) {
541 				}
542 				memsave(&up->u_primgrp, cp, strlen(cp));
543 			} else if (strncmp(s, "base_dir", 8) == 0) {
544 				for (cp = s + 8 ; *cp && isspace(*cp) ; cp++) {
545 				}
546 				memsave(&up->u_basedir, cp, strlen(cp));
547 			} else if (strncmp(s, "skel_dir", 8) == 0) {
548 				for (cp = s + 8 ; *cp && isspace(*cp) ; cp++) {
549 				}
550 				memsave(&up->u_skeldir, cp, strlen(cp));
551 			} else if (strncmp(s, "shell", 5) == 0) {
552 				for (cp = s + 5 ; *cp && isspace(*cp) ; cp++) {
553 				}
554 				memsave(&up->u_shell, cp, strlen(cp));
555 			} else if (strncmp(s, "inactive", 8) == 0) {
556 				for (cp = s + 8 ; *cp && isspace(*cp) ; cp++) {
557 				}
558 				up->u_inactive = atoi(cp);
559 #ifdef EXTENSIONS
560 			} else if (strncmp(s, "range", 5) == 0) {
561 				for (cp = s + 5 ; *cp && isspace(*cp) ; cp++) {
562 				}
563 				(void) save_range(up, cp);
564 #endif
565 #ifdef EXTENSIONS
566 			} else if (strncmp(s, "preserve", 8) == 0) {
567 				for (cp = s + 8 ; *cp && isspace(*cp) ; cp++) {
568 				}
569 				up->u_preserve = (strncmp(cp, "true", 4) == 0) ? 1 :
570 						  (strncmp(cp, "yes", 3) == 0) ? 1 :
571 						   atoi(cp);
572 #endif
573 			} else if (strncmp(s, "expire", 6) == 0) {
574 				for (cp = s + 6 ; *cp && isspace(*cp) ; cp++) {
575 				}
576 				if (strcmp(cp, UNSET_EXPIRY) == 0) {
577 					if (up->u_expire) {
578 						FREE(up->u_expire);
579 					}
580 					up->u_expire = (char *) NULL;
581 				} else {
582 					memsave(&up->u_expire, cp, strlen(cp));
583 				}
584 			}
585 			(void) free(s);
586 		}
587 		(void) fclose(fp);
588 	}
589 	if (up->u_rc == 0) {
590 		up->u_rv[up->u_rc].r_from = DEF_LOWUID;
591 		up->u_rv[up->u_rc].r_to = DEF_HIGHUID;
592 		up->u_rc += 1;
593 	}
594 	up->u_defrc = up->u_rc;
595 }
596 
597 /* return the next valid unused uid */
598 static int
599 getnextuid(int sync_uid_gid, int *uid, int low_uid, int high_uid)
600 {
601 	for (*uid = low_uid ; *uid <= high_uid ; (*uid)++) {
602 		if (getpwuid((uid_t)(*uid)) == (struct passwd *) NULL && *uid != NOBODY_UID) {
603 			if (sync_uid_gid) {
604 				if (getgrgid((gid_t)(*uid)) == (struct group *) NULL) {
605 					return 1;
606 				}
607 			} else {
608 				return 1;
609 			}
610 		}
611 	}
612 	return 0;
613 }
614 
615 /* add a user */
616 static int
617 adduser(char *login, user_t *up)
618 {
619 	struct group	*grp;
620 	struct stat	st;
621 	struct tm	tm;
622 	time_t		expire;
623 	char		password[PasswordLength + 1];
624 	char		home[MaxFileNameLen];
625 	char		buf[MaxFileNameLen];
626 	int		sync_uid_gid;
627 	int		masterfd;
628 	int		ptmpfd;
629 	int		gid;
630 	int		cc;
631 	int		i;
632 
633 	if (!valid_login(login)) {
634 		errx(EXIT_FAILURE, "`%s' is not a valid login name", login);
635 	}
636 	if ((masterfd = open(MASTER, O_RDONLY)) < 0) {
637 		err(EXIT_FAILURE, "can't open `%s'", MASTER);
638 	}
639 	if (flock(masterfd, LOCK_EX | LOCK_NB) < 0) {
640 		err(EXIT_FAILURE, "can't lock `%s'", MASTER);
641 	}
642 	pw_init();
643 	if ((ptmpfd = pw_lock(WAITSECS)) < 0) {
644 		(void) close(masterfd);
645 		err(EXIT_FAILURE, "can't obtain pw_lock");
646 	}
647 	while ((cc = read(masterfd, buf, sizeof(buf))) > 0) {
648 		if (write(ptmpfd, buf, (size_t)(cc)) != cc) {
649 			(void) close(masterfd);
650 			(void) close(ptmpfd);
651 			(void) pw_abort();
652 			err(EXIT_FAILURE, "short write to /etc/ptmp (not %d chars)", cc);
653 		}
654 	}
655 	/* if no uid was specified, get next one in [low_uid..high_uid] range */
656 	sync_uid_gid = (strcmp(up->u_primgrp, "=uid") == 0);
657 	if (up->u_uid == -1) {
658 		for (i = 0 ; i < up->u_rc ; i++) {
659 			if (getnextuid(sync_uid_gid, &up->u_uid, up->u_rv[i].r_from, up->u_rv[i].r_to)) {
660 				break;
661 			}
662 		}
663 		if (i == up->u_rc) {
664 			(void) close(ptmpfd);
665 			(void) pw_abort();
666 			errx(EXIT_FAILURE, "can't get next uid for %d", up->u_uid);
667 		}
668 	}
669 	/* check uid isn't already allocated */
670 	if (!up->u_dupuid && getpwuid((uid_t)(up->u_uid)) != (struct passwd *) NULL) {
671 		(void) close(ptmpfd);
672 		(void) pw_abort();
673 		errx(EXIT_FAILURE, "uid %d is already in use", up->u_uid);
674 	}
675 	/* if -g=uid was specified, check gid is unused */
676 	if (sync_uid_gid) {
677 		if (getgrgid((gid_t)(up->u_uid)) != (struct group *) NULL) {
678 			(void) close(ptmpfd);
679 			(void) pw_abort();
680 			errx(EXIT_FAILURE, "gid %d is already in use", up->u_uid);
681 		}
682 		gid = up->u_uid;
683 	} else if ((grp = getgrnam(up->u_primgrp)) != (struct group *) NULL) {
684 		gid = grp->gr_gid;
685 	} else if (is_number(up->u_primgrp) &&
686 		   (grp = getgrgid((gid_t)atoi(up->u_primgrp))) != (struct group *) NULL) {
687 		gid = grp->gr_gid;
688 	} else {
689 		(void) close(ptmpfd);
690 		(void) pw_abort();
691 		errx(EXIT_FAILURE, "group %s not found", up->u_primgrp);
692 	}
693 	/* check name isn't already in use */
694 	if (!up->u_dupuid && getpwnam(login) != (struct passwd *) NULL) {
695 		(void) close(ptmpfd);
696 		(void) pw_abort();
697 		errx(EXIT_FAILURE, "already a `%s' user", login);
698 	}
699 	/* if home directory hasn't been given, make it up */
700 	if (!up->u_homeset) {
701 		(void) snprintf(home, sizeof(home), "%s/%s", up->u_basedir, login);
702 	}
703 	expire = 0;
704 	if (up->u_expire != (char *) NULL) {
705 		(void) memset(&tm, 0, sizeof(tm));
706 		if (strptime(up->u_expire, "%c", &tm) == (char *) NULL) {
707 			warnx("invalid time format `%s'", optarg);
708 		} else {
709 			expire = mktime(&tm);
710 		}
711 	}
712 	password[PasswordLength] = 0;
713 	if (up->u_password != (char *) NULL &&
714 	    strlen(up->u_password) == PasswordLength) {
715 		(void) memcpy(password, up->u_password, PasswordLength);
716 	} else {
717 		(void) memset(password, '*', PasswordLength);
718 		if (up->u_password != (char *) NULL) {
719 			warnx("Password `%s' is invalid: setting it to `%s'",
720 				up->u_password, password);
721 		}
722 	}
723 	cc = snprintf(buf, sizeof(buf), "%s:%s:%d:%d::%d:%ld:%s:%s:%s\n",
724 			login,
725 			password,
726 			up->u_uid,
727 			gid,
728 			up->u_inactive,
729 			(long) expire,
730 			up->u_comment,
731 			home,
732 			up->u_shell);
733 	if (write(ptmpfd, buf, (size_t) cc) != cc) {
734 		(void) close(ptmpfd);
735 		(void) pw_abort();
736 		err(EXIT_FAILURE, "can't add `%s'", buf);
737 	}
738 	if (up->u_mkdir) {
739 		if (lstat(home, &st) < 0 && asystem("%s -p %s", MKDIR, home) != 0) {
740 			(void) close(ptmpfd);
741 			(void) pw_abort();
742 			err(EXIT_FAILURE, "can't mkdir `%s'", home);
743 		}
744 		(void) copydotfiles(up->u_skeldir, up->u_uid, gid, home);
745 	}
746 	if (strcmp(up->u_primgrp, "=uid") == 0 &&
747 	    getgrnam(login) == (struct group *) NULL &&
748 	    !creategid(login, gid, login)) {
749 		(void) close(ptmpfd);
750 		(void) pw_abort();
751 		err(EXIT_FAILURE, "can't create gid %d for login name %s", gid, login);
752 	}
753 	(void) close(ptmpfd);
754 	if (pw_mkdb() < 0) {
755 		err(EXIT_FAILURE, "pw_mkdb failed");
756 	}
757 	return 1;
758 }
759 
760 /* modify a user */
761 static int
762 moduser(char *login, char *newlogin, user_t *up)
763 {
764 	struct passwd	*pwp;
765 	struct group	*grp;
766 	struct tm	tm;
767 	time_t		expire;
768 	size_t		loginc;
769 	size_t		colonc;
770 	FILE		*master;
771 	char		password[PasswordLength + 1];
772 	char		oldhome[MaxFileNameLen];
773 	char		home[MaxFileNameLen];
774 	char		buf[MaxFileNameLen];
775 	char		*colon;
776 	int		masterfd;
777 	int		ptmpfd;
778 	int		gid;
779 	int		cc;
780 
781 	if (!valid_login(newlogin)) {
782 		errx(EXIT_FAILURE, "`%s' is not a valid login name", login);
783 	}
784 	if ((pwp = getpwnam(login)) == (struct passwd *) NULL) {
785 		errx(EXIT_FAILURE, "No such user `%s'", login);
786 	}
787 	if ((masterfd = open(MASTER, O_RDONLY)) < 0) {
788 		err(EXIT_FAILURE, "can't open `%s'", MASTER);
789 	}
790 	if (flock(masterfd, LOCK_EX | LOCK_NB) < 0) {
791 		err(EXIT_FAILURE, "can't lock `%s'", MASTER);
792 	}
793 	pw_init();
794 	if ((ptmpfd = pw_lock(WAITSECS)) < 0) {
795 		(void) close(masterfd);
796 		err(EXIT_FAILURE, "can't obtain pw_lock");
797 	}
798 	if ((master = fdopen(masterfd, "r")) == (FILE *) NULL) {
799 		(void) close(masterfd);
800 		(void) close(ptmpfd);
801 		(void) pw_abort();
802 		err(EXIT_FAILURE, "can't fdopen fd for %s", MASTER);
803 	}
804 	if (up != (user_t *) NULL) {
805 		if (up->u_mkdir) {
806 			(void) strcpy(oldhome, pwp->pw_dir);
807 		}
808 		if (up->u_uid == -1) {
809 			up->u_uid = pwp->pw_uid;
810 		}
811 		/* if -g=uid was specified, check gid is unused */
812 		if (strcmp(up->u_primgrp, "=uid") == 0) {
813 			if (getgrgid((gid_t)(up->u_uid)) != (struct group *) NULL) {
814 				(void) close(ptmpfd);
815 				(void) pw_abort();
816 				errx(EXIT_FAILURE, "gid %d is already in use", up->u_uid);
817 			}
818 			gid = up->u_uid;
819 		} else if ((grp = getgrnam(up->u_primgrp)) != (struct group *) NULL) {
820 			gid = grp->gr_gid;
821 		} else if (is_number(up->u_primgrp) &&
822 			   (grp = getgrgid((gid_t)atoi(up->u_primgrp))) != (struct group *) NULL) {
823 			gid = grp->gr_gid;
824 		} else {
825 			(void) close(ptmpfd);
826 			(void) pw_abort();
827 			errx(EXIT_FAILURE, "group %s not found", up->u_primgrp);
828 		}
829 		/* if changing name, check new name isn't already in use */
830 		if (strcmp(login, newlogin) != 0 && getpwnam(newlogin) != (struct passwd *) NULL) {
831 			(void) close(ptmpfd);
832 			(void) pw_abort();
833 			errx(EXIT_FAILURE, "already a `%s' user", newlogin);
834 		}
835 		/* if home directory hasn't been given, use the old one */
836 		if (!up->u_homeset) {
837 			(void) strcpy(home, pwp->pw_dir);
838 		}
839 		expire = 0;
840 		if (up->u_expire != (char *) NULL) {
841 			(void) memset(&tm, 0, sizeof(tm));
842 			if (strptime(up->u_expire, "%c", &tm) == (char *) NULL) {
843 				warnx("invalid time format `%s'", optarg);
844 			} else {
845 				expire = mktime(&tm);
846 			}
847 		}
848 		password[PasswordLength] = 0;
849 		if (up->u_password != (char *) NULL &&
850 		    strlen(up->u_password) == PasswordLength) {
851 			(void) memcpy(password, up->u_password, PasswordLength);
852 		} else {
853 			(void) memcpy(password, pwp->pw_passwd, PasswordLength);
854 		}
855 		if (strcmp(up->u_comment, DEF_COMMENT) == 0) {
856 			memsave(&up->u_comment, pwp->pw_gecos, strlen(pwp->pw_gecos));
857 		}
858 		if (strcmp(up->u_shell, DEF_SHELL) == 0 && strcmp(pwp->pw_shell, DEF_SHELL) != 0) {
859 			memsave(&up->u_comment, pwp->pw_shell, strlen(pwp->pw_shell));
860 		}
861 	}
862 	loginc = strlen(login);
863 	while (fgets(buf, sizeof(buf), master) != (char *) NULL) {
864 		cc = strlen(buf);
865 		if ((colon = strchr(buf, ':')) == (char *) NULL) {
866 			warnx("Malformed entry `%s'. Skipping", buf);
867 			continue;
868 		}
869 		colonc = (size_t)(colon - buf);
870 		if (strncmp(login, buf, loginc) == 0 && loginc == colonc) {
871 			if (up != (user_t *) NULL) {
872 				cc = snprintf(buf, sizeof(buf), "%s:%s:%d:%d::%d:%ld:%s:%s:%s\n",
873 					newlogin,
874 					password,
875 					up->u_uid,
876 					gid,
877 					up->u_inactive,
878 					(long) expire,
879 					up->u_comment,
880 					home,
881 					up->u_shell);
882 				if (write(ptmpfd, buf, (size_t) cc) != cc) {
883 					(void) close(ptmpfd);
884 					(void) pw_abort();
885 					err(EXIT_FAILURE, "can't add `%s'", buf);
886 				}
887 			}
888 		} else if (write(ptmpfd, buf, (size_t)(cc)) != cc) {
889 			(void) close(masterfd);
890 			(void) close(ptmpfd);
891 			(void) pw_abort();
892 			err(EXIT_FAILURE, "short write to /etc/ptmp (not %d chars)", cc);
893 		}
894 	}
895 	if (up != (user_t *) NULL &&
896 	    up->u_mkdir &&
897 	    asystem("%s %s %s", MV, oldhome, home) != 0) {
898 		(void) close(ptmpfd);
899 		(void) pw_abort();
900 		err(EXIT_FAILURE, "can't move `%s' to `%s'", oldhome, home);
901 	}
902 	(void) close(ptmpfd);
903 	if (pw_mkdb() < 0) {
904 		err(EXIT_FAILURE, "pw_mkdb failed");
905 	}
906 	return 1;
907 }
908 
909 
910 #ifdef EXTENSIONS
911 /* see if we can find out the user struct */
912 static struct passwd *
913 find_user_info(char *name)
914 {
915 	struct passwd	*pwp;
916 
917 	if ((pwp = getpwnam(name)) != (struct passwd *) NULL) {
918 		return pwp;
919 	}
920 	if (is_number(name) && (pwp = getpwuid((uid_t)atoi(name))) != (struct passwd *) NULL) {
921 		return pwp;
922 	}
923 	return (struct passwd *) NULL;
924 }
925 #endif
926 
927 #ifdef EXTENSIONS
928 /* see if we can find out the group struct */
929 static struct group *
930 find_group_info(char *name)
931 {
932 	struct group	*grp;
933 
934 	if ((grp = getgrnam(name)) != (struct group *) NULL) {
935 		return grp;
936 	}
937 	if (is_number(name) && (grp = getgrgid((gid_t)atoi(name))) != (struct group *) NULL) {
938 		return grp;
939 	}
940 	return (struct group *) NULL;
941 }
942 #endif
943 
944 /* print out usage message, and then exit */
945 void
946 usermgmt_usage(char *prog)
947 {
948 	if (strcmp(prog, "useradd") == 0) {
949 		(void) fprintf(stderr, "Usage: %s -D [-b basedir] [-e expiry] [-f inactive] [-g group] [-r lowuid..highuid] [-s shell]\n", prog);
950 		(void) fprintf(stderr, "Usage: %s [-G group] [-b basedir] [-c comment] [-d homedir] [-e expiry] [-f inactive]\n\t[-g group] [-k skeletondir] [-m] [-o] [-p password] [-r lowuid..highuid] [-s shell]\n\t[-u uid] [-v] user\n", prog);
951 	} else if (strcmp(prog, "usermod") == 0) {
952 		(void) fprintf(stderr, "Usage: %s [-G group] [-c comment] [-d homedir] [-e expire] [-f inactive] [-g group] [-l newname] [-m] [-o] [-p password] [-s shell] [-u uid] [-v] user\n", prog);
953 	} else if (strcmp(prog, "userdel") == 0) {
954 		(void) fprintf(stderr, "Usage: %s -D [-p preserve]\n", prog);
955 		(void) fprintf(stderr, "Usage: %s [-p preserve] [-r] [-v] user\n", prog);
956 #ifdef EXTENSIONS
957 	} else if (strcmp(prog, "userinfo") == 0) {
958 		(void) fprintf(stderr, "Usage: %s [-e] [-v] user\n", prog);
959 #endif
960 	} else if (strcmp(prog, "groupadd") == 0) {
961 		(void) fprintf(stderr, "Usage: %s [-g gid] [-o] [-v] group\n", prog);
962 	} else if (strcmp(prog, "groupdel") == 0) {
963 		(void) fprintf(stderr, "Usage: %s [-v] group\n", prog);
964 	} else if (strcmp(prog, "groupmod") == 0) {
965 		(void) fprintf(stderr, "Usage: %s [-g gid] [-o] [-n newname] [-v] group\n", prog);
966 	} else if (strcmp(prog, "user") == 0 || strcmp(prog, "group") == 0) {
967 		(void) fprintf(stderr, "Usage: %s ( add | del | mod ) ...\n", prog);
968 #ifdef EXTENSIONS
969 	} else if (strcmp(prog, "groupinfo") == 0) {
970 		(void) fprintf(stderr, "Usage: %s [-e] [-v] group\n", prog);
971 #endif
972 	}
973 	exit(EXIT_FAILURE);
974 	/* NOTREACHED */
975 }
976 
977 extern int	optind;
978 extern char	*optarg;
979 
980 #ifdef EXTENSIONS
981 #define ADD_OPT_EXTENSIONS	"p:r:v"
982 #else
983 #define ADD_OPT_EXTENSIONS
984 #endif
985 
986 int
987 useradd(int argc, char **argv)
988 {
989 	user_t	u;
990 	int	defaultfield;
991 	int	bigD;
992 	int	c;
993 	int	i;
994 
995 	(void) memset(&u, 0, sizeof(u));
996 	read_defaults(&u);
997 	u.u_uid = -1;
998 	defaultfield = bigD = 0;
999 	while ((c = getopt(argc, argv, "DG:b:c:d:e:f:g:k:mou:s:" ADD_OPT_EXTENSIONS)) != -1) {
1000 		switch(c) {
1001 		case 'D':
1002 			bigD = 1;
1003 			break;
1004 		case 'G':
1005 			memsave(&u.u_groupv[u.u_groupc++], optarg, strlen(optarg));
1006 			break;
1007 		case 'b':
1008 			defaultfield = 1;
1009 			memsave(&u.u_basedir, optarg, strlen(optarg));
1010 			break;
1011 		case 'c':
1012 			memsave(&u.u_comment, optarg, strlen(optarg));
1013 			break;
1014 		case 'd':
1015 			u.u_homeset = 1;
1016 			memsave(&u.u_home, optarg, strlen(optarg));
1017 			break;
1018 		case 'e':
1019 			defaultfield = 1;
1020 			memsave(&u.u_expire, optarg, strlen(optarg));
1021 			break;
1022 		case 'f':
1023 			defaultfield = 1;
1024 			u.u_inactive = atoi(optarg);
1025 			break;
1026 		case 'g':
1027 			defaultfield = 1;
1028 			memsave(&u.u_primgrp, optarg, strlen(optarg));
1029 			break;
1030 		case 'k':
1031 			memsave(&u.u_skeldir, optarg, strlen(optarg));
1032 			break;
1033 		case 'm':
1034 			u.u_mkdir = 1;
1035 			break;
1036 		case 'o':
1037 			u.u_dupuid = 1;
1038 			break;
1039 #ifdef EXTENSIONS
1040 		case 'p':
1041 			memsave(&u.u_password, optarg, strlen(optarg));
1042 			break;
1043 #endif
1044 #ifdef EXTENSIONS
1045 		case 'r':
1046 			defaultfield = 1;
1047 			(void) save_range(&u, optarg);
1048 			break;
1049 #endif
1050 		case 's':
1051 			defaultfield = 1;
1052 			memsave(&u.u_shell, optarg, strlen(optarg));
1053 			break;
1054 		case 'u':
1055 			if (!is_number(optarg)) {
1056 				errx(EXIT_FAILURE, "When using [-u uid], the uid must be numeric");
1057 			}
1058 			u.u_uid = atoi(optarg);
1059 			break;
1060 #ifdef EXTENSIONS
1061 		case 'v':
1062 			verbose = 1;
1063 			break;
1064 #endif
1065 		}
1066 	}
1067 	if (bigD) {
1068 		if (defaultfield) {
1069 			checkeuid();
1070 			return setdefaults(&u) ? EXIT_SUCCESS : EXIT_FAILURE;
1071 		}
1072 		(void) printf("group\t\t%s\n", u.u_primgrp);
1073 		(void) printf("base_dir\t%s\n", u.u_basedir);
1074 		(void) printf("skel_dir\t%s\n", u.u_skeldir);
1075 		(void) printf("shell\t\t%s\n", u.u_shell);
1076 		(void) printf("inactive\t%d\n", u.u_inactive);
1077 		(void) printf("expire\t\t%s\n", (u.u_expire == (char *) NULL) ? UNSET_EXPIRY : u.u_expire);
1078 #ifdef EXTENSIONS
1079 		for (i = 0 ; i < u.u_rc ; i++) {
1080 			(void) printf("range\t\t%d..%d\n", u.u_rv[i].r_from, u.u_rv[i].r_to);
1081 		}
1082 #endif
1083 		return EXIT_SUCCESS;
1084 	}
1085 	if (argc == optind) {
1086 		usermgmt_usage("useradd");
1087 	}
1088 	checkeuid();
1089 	return adduser(argv[optind], &u) ? EXIT_SUCCESS : EXIT_FAILURE;
1090 }
1091 
1092 #ifdef EXTENSIONS
1093 #define MOD_OPT_EXTENSIONS	"p:v"
1094 #else
1095 #define MOD_OPT_EXTENSIONS
1096 #endif
1097 
1098 int
1099 usermod(int argc, char **argv)
1100 {
1101 	user_t	u;
1102 	char	newuser[MaxUserNameLen + 1];
1103 	int	have_new_user;
1104 	int	c;
1105 
1106 	checkeuid();
1107 	(void) memset(&u, 0, sizeof(u));
1108 	(void) memset(newuser, 0, sizeof(newuser));
1109 	read_defaults(&u);
1110 	u.u_uid = -1;
1111 	have_new_user = 0;
1112 	while ((c = getopt(argc, argv, "G:c:d:e:f:g:l:mos:u:" MOD_OPT_EXTENSIONS)) != -1) {
1113 		switch(c) {
1114 		case 'G':
1115 			memsave(&u.u_groupv[u.u_groupc++], optarg, strlen(optarg));
1116 			break;
1117 		case 'c':
1118 			memsave(&u.u_comment, optarg, strlen(optarg));
1119 			break;
1120 		case 'd':
1121 			u.u_homeset = 1;
1122 			memsave(&u.u_home, optarg, strlen(optarg));
1123 			break;
1124 		case 'e':
1125 			memsave(&u.u_expire, optarg, strlen(optarg));
1126 			break;
1127 		case 'f':
1128 			u.u_inactive = atoi(optarg);
1129 			break;
1130 		case 'g':
1131 			memsave(&u.u_primgrp, optarg, strlen(optarg));
1132 			break;
1133 		case 'l':
1134 			have_new_user = 1;
1135 			(void) strlcpy(newuser, optarg, sizeof(newuser));
1136 			break;
1137 		case 'm':
1138 			u.u_mkdir = 1;
1139 			break;
1140 		case 'o':
1141 			u.u_dupuid = 1;
1142 			break;
1143 #ifdef EXTENSIONS
1144 		case 'p':
1145 			memsave(&u.u_password, optarg, strlen(optarg));
1146 			break;
1147 #endif
1148 		case 's':
1149 			memsave(&u.u_shell, optarg, strlen(optarg));
1150 			break;
1151 		case 'u':
1152 			if (!is_number(optarg)) {
1153 				errx(EXIT_FAILURE, "When using [-u uid], the uid must be numeric");
1154 			}
1155 			u.u_uid = atoi(optarg);
1156 			break;
1157 #ifdef EXTENSIONS
1158 		case 'v':
1159 			verbose = 1;
1160 			break;
1161 #endif
1162 		}
1163 	}
1164 	if (argc == optind) {
1165 		usermgmt_usage("usermod");
1166 	}
1167 	return moduser(argv[optind], (have_new_user) ? newuser : argv[optind], &u) ? EXIT_SUCCESS : EXIT_FAILURE;
1168 }
1169 
1170 #ifdef EXTENSIONS
1171 #define DEL_OPT_EXTENSIONS	"Dp:v"
1172 #else
1173 #define DEL_OPT_EXTENSIONS
1174 #endif
1175 
1176 int
1177 userdel(int argc, char **argv)
1178 {
1179 	struct passwd	*pwp;
1180 	struct stat	st;
1181 	user_t		u;
1182 	char		password[PasswordLength + 1];
1183 	int		defaultfield;
1184 	int		rmhome;
1185 	int		bigD;
1186 	int		c;
1187 
1188 	if (geteuid() != 0) {
1189 		errx(EXIT_FAILURE, "Program must be run as root");
1190 	}
1191 	(void) memset(&u, 0, sizeof(u));
1192 	read_defaults(&u);
1193 	defaultfield = bigD = rmhome = 0;
1194 	while ((c = getopt(argc, argv, "r" DEL_OPT_EXTENSIONS)) != -1) {
1195 		switch(c) {
1196 #ifdef EXTENSIONS
1197 		case 'D':
1198 			bigD = 1;
1199 			break;
1200 #endif
1201 #ifdef EXTENSIONS
1202 		case 'p':
1203 			defaultfield = 1;
1204 			u.u_preserve = (strcmp(optarg, "true") == 0) ? 1 :
1205 					(strcmp(optarg, "yes") == 0) ? 1 :
1206 					 atoi(optarg);
1207 			break;
1208 #endif
1209 		case 'r':
1210 			rmhome = 1;
1211 			break;
1212 #ifdef EXTENSIONS
1213 		case 'v':
1214 			verbose = 1;
1215 			break;
1216 #endif
1217 		}
1218 	}
1219 #ifdef EXTENSIONS
1220 	if (bigD) {
1221 		if (defaultfield) {
1222 			checkeuid();
1223 			return setdefaults(&u) ? EXIT_SUCCESS : EXIT_FAILURE;
1224 		}
1225 		(void) printf("preserve\t%s\n", (u.u_preserve) ? "true" : "false");
1226 		return EXIT_SUCCESS;
1227 	}
1228 #endif
1229 	if (argc == optind) {
1230 		usermgmt_usage("userdel");
1231 	}
1232 	checkeuid();
1233 	if ((pwp = getpwnam(argv[optind])) == (struct passwd *) NULL) {
1234 		warnx("No such user `%s'", argv[optind]);
1235 		return EXIT_FAILURE;
1236 	}
1237 	if (rmhome) {
1238 		if (stat(pwp->pw_dir, &st) < 0) {
1239 			warn("Home directory `%s' does not exist", pwp->pw_dir);
1240 			return EXIT_FAILURE;
1241 		}
1242 		(void) asystem("%s -rf %s", RM, pwp->pw_dir);
1243 	}
1244 	if (u.u_preserve) {
1245 		memsave(&u.u_shell, NOLOGIN, strlen(NOLOGIN));
1246 		(void) memset(password, '*', PasswordLength);
1247 		password[PasswordLength] = 0;
1248 		memsave(&u.u_password, password, PasswordLength);
1249 		return moduser(argv[optind], argv[optind], &u) ? EXIT_SUCCESS : EXIT_FAILURE;
1250 	}
1251 	return moduser(argv[optind], argv[optind], (user_t *) NULL) ? EXIT_SUCCESS : EXIT_FAILURE;
1252 }
1253 
1254 #ifdef EXTENSIONS
1255 #define GROUP_ADD_OPT_EXTENSIONS	"v"
1256 #else
1257 #define GROUP_ADD_OPT_EXTENSIONS
1258 #endif
1259 
1260 /* add a group */
1261 int
1262 groupadd(int argc, char **argv)
1263 {
1264 	int	dupgid;
1265 	int	gid;
1266 	int	c;
1267 
1268 	checkeuid();
1269 	gid = -1;
1270 	dupgid = 0;
1271 	while ((c = getopt(argc, argv, "g:o" GROUP_ADD_OPT_EXTENSIONS)) != -1) {
1272 		switch(c) {
1273 		case 'g':
1274 			if (!is_number(optarg)) {
1275 				errx(EXIT_FAILURE, "When using [-g gid], the gid must be numeric");
1276 			}
1277 			gid = atoi(optarg);
1278 			break;
1279 		case 'o':
1280 			dupgid = 1;
1281 			break;
1282 #ifdef EXTENSIONS
1283 		case 'v':
1284 			verbose = 1;
1285 			break;
1286 #endif
1287 		}
1288 	}
1289 	if (argc == optind) {
1290 		usermgmt_usage("groupadd");
1291 	}
1292 	if (gid < 0 && !getnextgid(&gid, LowGid, HighGid)) {
1293 		err(EXIT_FAILURE, "can't add group: can't get next gid");
1294 	}
1295 	if (!dupgid && getgrgid((gid_t) gid) != (struct group *) NULL) {
1296 		errx(EXIT_FAILURE, "can't add group: gid %d is a duplicate", gid);
1297 	}
1298 	if (!valid_group(argv[optind])) {
1299 		warnx("warning - invalid group name `%s'", argv[optind]);
1300 	}
1301 	if (!creategid(argv[optind], gid, "")) {
1302 		err(EXIT_FAILURE, "can't add group: problems with %s file", ETCGROUP);
1303 	}
1304 	return EXIT_SUCCESS;
1305 }
1306 
1307 #ifdef EXTENSIONS
1308 #define GROUP_DEL_OPT_EXTENSIONS	"v"
1309 #else
1310 #define GROUP_DEL_OPT_EXTENSIONS
1311 #endif
1312 
1313 /* remove a group */
1314 int
1315 groupdel(int argc, char **argv)
1316 {
1317 	int	c;
1318 
1319 	checkeuid();
1320 	while ((c = getopt(argc, argv, "" GROUP_DEL_OPT_EXTENSIONS)) != -1) {
1321 		switch(c) {
1322 #ifdef EXTENSIONS
1323 		case 'v':
1324 			verbose = 1;
1325 			break;
1326 #endif
1327 		}
1328 	}
1329 	if (argc == optind) {
1330 		usermgmt_usage("groupdel");
1331 	}
1332 	if (!modify_gid(argv[optind], (char *) NULL)) {
1333 		err(EXIT_FAILURE, "can't change %s file", ETCGROUP);
1334 	}
1335 	return EXIT_SUCCESS;
1336 }
1337 
1338 #ifdef EXTENSIONS
1339 #define GROUP_MOD_OPT_EXTENSIONS	"v"
1340 #else
1341 #define GROUP_MOD_OPT_EXTENSIONS
1342 #endif
1343 
1344 /* modify a group */
1345 int
1346 groupmod(int argc, char **argv)
1347 {
1348 	struct group	*grp;
1349 	char		buf[MaxEntryLen];
1350 	char		*newname;
1351 	char		**cpp;
1352 	int		dupgid;
1353 	int		gid;
1354 	int		cc;
1355 	int		c;
1356 
1357 	checkeuid();
1358 	gid = -1;
1359 	dupgid = 0;
1360 	newname = (char *) NULL;
1361 	while ((c = getopt(argc, argv, "g:on:" GROUP_MOD_OPT_EXTENSIONS)) != -1) {
1362 		switch(c) {
1363 		case 'g':
1364 			if (!is_number(optarg)) {
1365 				errx(EXIT_FAILURE, "When using [-g gid], the gid must be numeric");
1366 			}
1367 			gid = atoi(optarg);
1368 			break;
1369 		case 'o':
1370 			dupgid = 1;
1371 			break;
1372 		case 'n':
1373 			memsave(&newname, optarg, strlen(optarg));
1374 			break;
1375 #ifdef EXTENSIONS
1376 		case 'v':
1377 			verbose = 1;
1378 			break;
1379 #endif
1380 		}
1381 	}
1382 	if (argc == optind) {
1383 		usermgmt_usage("groupmod");
1384 	}
1385 	if (gid < 0 && newname == (char *) NULL) {
1386 		err(EXIT_FAILURE, "Nothing to change");
1387 	}
1388 	if (dupgid && gid < 0) {
1389 		err(EXIT_FAILURE, "Duplicate which gid?");
1390 	}
1391 	if ((grp = getgrnam(argv[optind])) == (struct group *) NULL) {
1392 		err(EXIT_FAILURE, "can't find group `%s' to modify", argv[optind]);
1393 	}
1394 	if (newname != (char *) NULL && !valid_group(newname)) {
1395 		warn("warning - invalid group name `%s'", newname);
1396 	}
1397 	cc = snprintf(buf, sizeof(buf), "%s:%s:%d:",
1398 			(newname) ? newname : grp->gr_name,
1399 			grp->gr_passwd,
1400 			(gid < 0) ? grp->gr_gid : gid);
1401 	for (cpp = grp->gr_mem ; *cpp && cc < sizeof(buf) ; cpp++) {
1402 		cc += snprintf(&buf[cc], sizeof(buf) - cc, "%s%s", *cpp,
1403 			(cpp[1] == (char *) NULL) ? "" : ",");
1404 	}
1405 	if (!modify_gid(argv[optind], buf)) {
1406 		err(EXIT_FAILURE, "can't change %s file", ETCGROUP);
1407 	}
1408 	return EXIT_SUCCESS;
1409 }
1410 
1411 #ifdef EXTENSIONS
1412 /* display user information */
1413 int
1414 userinfo(int argc, char **argv)
1415 {
1416 	struct passwd	*pwp;
1417 	struct group	*grp;
1418 	char		buf[MaxEntryLen];
1419 	char		**cpp;
1420 	int		exists;
1421 	int		cc;
1422 	int		i;
1423 
1424 	exists = 0;
1425 	while ((i = getopt(argc, argv, "ev")) != -1) {
1426 		switch(i) {
1427 		case 'e':
1428 			exists = 1;
1429 			break;
1430 		case 'v':
1431 			verbose = 1;
1432 			break;
1433 		}
1434 	}
1435 	if (argc == optind) {
1436 		usermgmt_usage("userinfo");
1437 	}
1438 	pwp = find_user_info(argv[optind]);
1439 	if (exists) {
1440 		exit((pwp) ? EXIT_SUCCESS : EXIT_FAILURE);
1441 	}
1442 	if (pwp == (struct passwd *) NULL) {
1443 		errx(EXIT_FAILURE, "can't find user `%s'", argv[optind]);
1444 	}
1445 	(void) printf("login\t%s\n", pwp->pw_name);
1446 	(void) printf("passwd\t%s\n", pwp->pw_passwd);
1447 	(void) printf("uid\t%d\n", pwp->pw_uid);
1448 	for (cc = 0 ; (grp = getgrent()) != (struct group *) NULL ; ) {
1449 		for (cpp = grp->gr_mem ; *cpp ; cpp++) {
1450 			if (strcmp(*cpp, argv[optind]) == 0 && grp->gr_gid != pwp->pw_gid) {
1451 				cc += snprintf(&buf[cc], sizeof(buf) - cc, "%s ", grp->gr_name);
1452 			}
1453 		}
1454 	}
1455 	if ((grp = getgrgid(pwp->pw_gid)) == (struct group *) NULL) {
1456 		(void) printf("groups\t%d %s\n", pwp->pw_gid, buf);
1457 	} else {
1458 		(void) printf("groups\t%s %s\n", grp->gr_name, buf);
1459 	}
1460 	(void) printf("change\t%s", ctime(&pwp->pw_change));
1461 	(void) printf("class\t%s\n", pwp->pw_class);
1462 	(void) printf("gecos\t%s\n", pwp->pw_gecos);
1463 	(void) printf("dir\t%s\n", pwp->pw_dir);
1464 	(void) printf("shell\t%s\n", pwp->pw_shell);
1465 	(void) printf("expire\t%s", ctime(&pwp->pw_expire));
1466 	return EXIT_SUCCESS;
1467 }
1468 #endif
1469 
1470 #ifdef EXTENSIONS
1471 /* display user information */
1472 int
1473 groupinfo(int argc, char **argv)
1474 {
1475 	struct group	*grp;
1476 	char		**cpp;
1477 	int		exists;
1478 	int		i;
1479 
1480 	exists = 0;
1481 	while ((i = getopt(argc, argv, "ev")) != -1) {
1482 		switch(i) {
1483 		case 'e':
1484 			exists = 1;
1485 			break;
1486 		case 'v':
1487 			verbose = 1;
1488 			break;
1489 		}
1490 	}
1491 	if (argc == optind) {
1492 		usermgmt_usage("groupinfo");
1493 	}
1494 	grp = find_group_info(argv[optind]);
1495 	if (exists) {
1496 		exit((grp) ? EXIT_SUCCESS : EXIT_FAILURE);
1497 	}
1498 	if (grp == (struct group *) NULL) {
1499 		errx(EXIT_FAILURE, "can't find group `%s'", argv[optind]);
1500 	}
1501 	(void) printf("name\t%s\n", grp->gr_name);
1502 	(void) printf("passwd\t%s\n", grp->gr_passwd);
1503 	(void) printf("gid\t%d\n", grp->gr_gid);
1504 	(void) printf("members\t");
1505 	for (cpp = grp->gr_mem ; *cpp ; cpp++) {
1506 		(void) printf("%s ", *cpp);
1507 	}
1508 	(void) fputc('\n', stdout);
1509 	return EXIT_SUCCESS;
1510 }
1511 #endif
1512