xref: /dragonfly/usr.sbin/pwd_mkdb/pwd_mkdb.c (revision 17b61719)
1 /*-
2  * Copyright (c) 1991, 1993, 1994
3  *	The Regents of the University of California.  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  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * @(#) Copyright (c) 1991, 1993, 1994 The Regents of the University of California.  All rights reserved.
34  * @(#)pwd_mkdb.c	8.5 (Berkeley) 4/20/94
35  * $FreeBSD: src/usr.sbin/pwd_mkdb/pwd_mkdb.c,v 1.35 2000/03/09 18:11:16 paul Exp $
36  * $DragonFly: src/usr.sbin/pwd_mkdb/pwd_mkdb.c,v 1.3 2003/11/03 19:31:41 eirikn Exp $
37  */
38 
39 #include <sys/param.h>
40 #include <sys/stat.h>
41 
42 #include <db.h>
43 #include <err.h>
44 #include <errno.h>
45 #include <fcntl.h>
46 #include <limits.h>
47 #include <pwd.h>
48 #include <signal.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <unistd.h>
53 
54 #include "pw_scan.h"
55 
56 #define	INSECURE	1
57 #define	SECURE		2
58 #define	PERM_INSECURE	(S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH)
59 #define	PERM_SECURE	(S_IRUSR|S_IWUSR)
60 
61 HASHINFO openinfo = {
62 	4096,		/* bsize */
63 	32,		/* ffactor */
64 	256,		/* nelem */
65 	2048 * 1024,	/* cachesize */
66 	NULL,		/* hash() */
67 	0		/* lorder */
68 };
69 
70 static enum state { FILE_INSECURE, FILE_SECURE, FILE_ORIG } clean;
71 static struct passwd pwd;			/* password structure */
72 static char *pname;				/* password file name */
73 static char prefix[MAXPATHLEN];
74 
75 static int is_comment;	/* flag for comments */
76 static char line[LINE_MAX];
77 
78 void	cleanup(void);
79 void	error(char *);
80 void	cp(char *, char *, mode_t mode);
81 void	mv(char *, char *);
82 int	scan(FILE *, struct passwd *);
83 static void	usage(void);
84 
85 int
86 main(argc, argv)
87 	int argc;
88 	char *argv[];
89 {
90 	DB *dp, *sdp, *pw_db;
91 	DBT data, sdata, key;
92 	FILE *fp, *oldfp;
93 	sigset_t set;
94 	int ch, cnt, ypcnt, len, makeold, tfd, yp_enabled = 0;
95 	char *p, *t;
96 	char buf[MAX(MAXPATHLEN, LINE_MAX * 2)], tbuf[1024];
97 	char sbuf[MAX(MAXPATHLEN, LINE_MAX * 2)];
98 	char buf2[MAXPATHLEN];
99 	char sbuf2[MAXPATHLEN];
100 	char *username;
101 	u_int method, methoduid;
102 	int Cflag;
103 	int nblock = 0;
104 
105 	Cflag = 0;
106 	strcpy(prefix, _PATH_PWD);
107 	makeold = 0;
108 	username = NULL;
109 	while ((ch = getopt(argc, argv, "Cd:ps:u:vN")) != -1)
110 		switch(ch) {
111 		case 'C':                       /* verify only */
112 			Cflag = 1;
113 			break;
114 		case 'd':
115 			strncpy(prefix, optarg, sizeof prefix - 1);
116 			break;
117 		case 'p':			/* create V7 "file.orig" */
118 			makeold = 1;
119 			break;
120 		case 's':			/* change default cachesize */
121 			openinfo.cachesize = atoi(optarg) * 1024 * 1024;
122 			break;
123 		case 'u':			/* only update this record */
124 			username = optarg;
125 			break;
126 		case 'v':                       /* backward compatible */
127 			break;
128 		case 'N':			/* do not wait for lock	*/
129 			nblock = LOCK_NB;
130 			break;
131 		default:
132 			usage();
133 		}
134 	argc -= optind;
135 	argv += optind;
136 
137 	if (argc != 1 || (username && (*username == '+' || *username == '-')))
138 		usage();
139 
140 	/*
141 	 * This could be changed to allow the user to interrupt.
142 	 * Probably not worth the effort.
143 	 */
144 	sigemptyset(&set);
145 	sigaddset(&set, SIGTSTP);
146 	sigaddset(&set, SIGHUP);
147 	sigaddset(&set, SIGINT);
148 	sigaddset(&set, SIGQUIT);
149 	sigaddset(&set, SIGTERM);
150 	(void)sigprocmask(SIG_BLOCK, &set, (sigset_t *)NULL);
151 
152 	/* We don't care what the user wants. */
153 	(void)umask(0);
154 
155 	pname = *argv;
156 
157 	/*
158 	 * Open and lock the original password file.  We have to check
159 	 * the hardlink count after we get the lock to handle any potential
160 	 * unlink/rename race.
161 	 *
162 	 * This lock is necessary when someone runs pwd_mkdb manually, directly
163 	 * on master.passwd, to handle the case where a user might try to
164 	 * change his password while pwd_mkdb is running.
165 	 */
166 	for (;;) {
167 		struct stat st;
168 
169 		if (!(fp = fopen(pname, "r")))
170 			error(pname);
171 		if (flock(fileno(fp), LOCK_EX|nblock) < 0)
172 			error("flock");
173 		if (fstat(fileno(fp), &st) < 0)
174 			error(pname);
175 		if (st.st_nlink != 0)
176 			break;
177 		fclose(fp);
178 		fp = NULL;
179 	}
180 
181 	/* check only if password database is valid */
182 	if (Cflag) {
183 		for (cnt = 1; scan(fp, &pwd); ++cnt);
184 		exit(0);
185 	}
186 
187 	/* Open the temporary insecure password database. */
188 	(void)snprintf(buf, sizeof(buf), "%s/%s.tmp", prefix, _MP_DB);
189 	(void)snprintf(sbuf, sizeof(sbuf), "%s/%s.tmp", prefix, _SMP_DB);
190 	if (username) {
191 		(void)snprintf(buf2, sizeof(buf2), "%s/%s", prefix, _MP_DB);
192 		(void)snprintf(sbuf2, sizeof(sbuf2), "%s/%s", prefix, _SMP_DB);
193 
194 		clean = FILE_INSECURE;
195 		cp(buf2, buf, PERM_INSECURE);
196 		dp = dbopen(buf,
197 		    O_RDWR|O_EXCL, PERM_INSECURE, DB_HASH, &openinfo);
198 		if (dp == NULL)
199 			error(buf);
200 
201 		clean = FILE_SECURE;
202 		cp(sbuf2, sbuf, PERM_SECURE);
203 		sdp = dbopen(sbuf,
204 		    O_RDWR|O_EXCL, PERM_SECURE, DB_HASH, &openinfo);
205 		if (sdp == NULL)
206 			error(sbuf);
207 
208 		/*
209 		 * Do some trouble to check if we should store this users
210 		 * uid. Don't use getpwnam/getpwuid as that interferes
211 		 * with NIS.
212 		 */
213 		pw_db = dbopen(_PATH_MP_DB, O_RDONLY, 0, DB_HASH, NULL);
214 		if (!pw_db)
215 			error(_MP_DB);
216 		buf[0] = _PW_KEYBYNAME;
217 		len = strlen(username);
218 
219 		/* Only check that username fits in buffer */
220 		memmove(buf + 1, username, MIN(len, sizeof(buf) - 1));
221 		key.data = (u_char *)buf;
222 		key.size = len + 1;
223 		if ((pw_db->get)(pw_db, &key, &data, 0) == 0) {
224 			p = (char *)data.data;
225 
226 			/* jump over pw_name and pw_passwd, to get to pw_uid */
227 			while (*p++)
228 				;
229 			while (*p++)
230 				;
231 
232 			buf[0] = _PW_KEYBYUID;
233 			memmove(buf + 1, p, sizeof(int));
234 			key.data = (u_char *)buf;
235 			key.size = sizeof(int) + 1;
236 
237 			if ((pw_db->get)(pw_db, &key, &data, 0) == 0) {
238 				/* First field of data.data holds pw_pwname */
239 				if (!strcmp(data.data, username))
240 					methoduid = 0;
241 				else
242 					methoduid = R_NOOVERWRITE;
243 			} else {
244 				methoduid = R_NOOVERWRITE;
245 			}
246 		} else {
247 			methoduid = R_NOOVERWRITE;
248 		}
249 		if ((pw_db->close)(pw_db))
250 			error("close pw_db");
251 		method = 0;
252 	} else {
253 		dp = dbopen(buf,
254 		    O_RDWR|O_CREAT|O_EXCL, PERM_INSECURE, DB_HASH, &openinfo);
255 		if (dp == NULL)
256 			error(buf);
257 		clean = FILE_INSECURE;
258 
259 		sdp = dbopen(sbuf,
260 		    O_RDWR|O_CREAT|O_EXCL, PERM_SECURE, DB_HASH, &openinfo);
261 		if (sdp == NULL)
262 			error(sbuf);
263 		clean = FILE_SECURE;
264 
265 		method = R_NOOVERWRITE;
266 		methoduid = R_NOOVERWRITE;
267 	}
268 
269 	/*
270 	 * Open file for old password file.  Minor trickiness -- don't want to
271 	 * chance the file already existing, since someone (stupidly) might
272 	 * still be using this for permission checking.  So, open it first and
273 	 * fdopen the resulting fd.  The resulting file should be readable by
274 	 * everyone.
275 	 */
276 	if (makeold) {
277 		(void)snprintf(buf, sizeof(buf), "%s.orig", pname);
278 		if ((tfd = open(buf,
279 		    O_WRONLY|O_CREAT|O_EXCL, PERM_INSECURE)) < 0)
280 			error(buf);
281 		if ((oldfp = fdopen(tfd, "w")) == NULL)
282 			error(buf);
283 		clean = FILE_ORIG;
284 	}
285 
286 	/*
287 	 * The databases actually contain three copies of the original data.
288 	 * Each password file entry is converted into a rough approximation
289 	 * of a ``struct passwd'', with the strings placed inline.  This
290 	 * object is then stored as the data for three separate keys.  The
291 	 * first key * is the pw_name field prepended by the _PW_KEYBYNAME
292 	 * character.  The second key is the pw_uid field prepended by the
293 	 * _PW_KEYBYUID character.  The third key is the line number in the
294 	 * original file prepended by the _PW_KEYBYNUM character.  (The special
295 	 * characters are prepended to ensure that the keys do not collide.)
296 	 */
297 	ypcnt = 1;
298 	data.data = (u_char *)buf;
299 	sdata.data = (u_char *)sbuf;
300 	key.data = (u_char *)tbuf;
301 	for (cnt = 1; scan(fp, &pwd); ++cnt) {
302 		if (!is_comment &&
303 		    (pwd.pw_name[0] == '+' || pwd.pw_name[0] == '-'))
304 			yp_enabled = 1;
305 		if (is_comment)
306 			--cnt;
307 #define	COMPACT(e)	t = e; while ((*p++ = *t++));
308 		if (!is_comment &&
309 		    (!username || (strcmp(username, pwd.pw_name) == 0))) {
310 			/* Create insecure data. */
311 			p = buf;
312 			COMPACT(pwd.pw_name);
313 			COMPACT("*");
314 			memmove(p, &pwd.pw_uid, sizeof(pwd.pw_uid));
315 			p += sizeof(int);
316 			memmove(p, &pwd.pw_gid, sizeof(pwd.pw_gid));
317 			p += sizeof(int);
318 			memmove(p, &pwd.pw_change, sizeof(time_t));
319 			p += sizeof(time_t);
320 			COMPACT(pwd.pw_class);
321 			COMPACT(pwd.pw_gecos);
322 			COMPACT(pwd.pw_dir);
323 			COMPACT(pwd.pw_shell);
324 			memmove(p, &pwd.pw_expire, sizeof(time_t));
325 			p += sizeof(time_t);
326 			memmove(p, &pwd.pw_fields, sizeof pwd.pw_fields);
327 			p += sizeof pwd.pw_fields;
328 			data.size = p - buf;
329 
330 			/* Create secure data. */
331 			p = sbuf;
332 			COMPACT(pwd.pw_name);
333 			COMPACT(pwd.pw_passwd);
334 			memmove(p, &pwd.pw_uid, sizeof(pwd.pw_uid));
335 			p += sizeof(int);
336 			memmove(p, &pwd.pw_gid, sizeof(pwd.pw_gid));
337 			p += sizeof(int);
338 			memmove(p, &pwd.pw_change, sizeof(time_t));
339 			p += sizeof(time_t);
340 			COMPACT(pwd.pw_class);
341 			COMPACT(pwd.pw_gecos);
342 			COMPACT(pwd.pw_dir);
343 			COMPACT(pwd.pw_shell);
344 			memmove(p, &pwd.pw_expire, sizeof(time_t));
345 			p += sizeof(time_t);
346 			memmove(p, &pwd.pw_fields, sizeof pwd.pw_fields);
347 			p += sizeof pwd.pw_fields;
348 			sdata.size = p - sbuf;
349 
350 			/* Store insecure by name. */
351 			tbuf[0] = _PW_KEYBYNAME;
352 			len = strlen(pwd.pw_name);
353 			memmove(tbuf + 1, pwd.pw_name, len);
354 			key.size = len + 1;
355 			if ((dp->put)(dp, &key, &data, method) == -1)
356 				error("put");
357 
358 			/* Store insecure by number. */
359 			tbuf[0] = _PW_KEYBYNUM;
360 			memmove(tbuf + 1, &cnt, sizeof(cnt));
361 			key.size = sizeof(cnt) + 1;
362 			if ((dp->put)(dp, &key, &data, method) == -1)
363 				error("put");
364 
365 			/* Store insecure by uid. */
366 			tbuf[0] = _PW_KEYBYUID;
367 			memmove(tbuf + 1, &pwd.pw_uid, sizeof(pwd.pw_uid));
368 			key.size = sizeof(pwd.pw_uid) + 1;
369 			if ((dp->put)(dp, &key, &data, methoduid) == -1)
370 				error("put");
371 
372 			/* Store secure by name. */
373 			tbuf[0] = _PW_KEYBYNAME;
374 			len = strlen(pwd.pw_name);
375 			memmove(tbuf + 1, pwd.pw_name, len);
376 			key.size = len + 1;
377 			if ((sdp->put)(sdp, &key, &sdata, method) == -1)
378 				error("put");
379 
380 			/* Store secure by number. */
381 			tbuf[0] = _PW_KEYBYNUM;
382 			memmove(tbuf + 1, &cnt, sizeof(cnt));
383 			key.size = sizeof(cnt) + 1;
384 			if ((sdp->put)(sdp, &key, &sdata, method) == -1)
385 				error("put");
386 
387 			/* Store secure by uid. */
388 			tbuf[0] = _PW_KEYBYUID;
389 			memmove(tbuf + 1, &pwd.pw_uid, sizeof(pwd.pw_uid));
390 			key.size = sizeof(pwd.pw_uid) + 1;
391 			if ((sdp->put)(sdp, &key, &sdata, methoduid) == -1)
392 				error("put");
393 
394 			/* Store insecure and secure special plus and special minus */
395 			if (pwd.pw_name[0] == '+' || pwd.pw_name[0] == '-') {
396 				tbuf[0] = _PW_KEYYPBYNUM;
397 				memmove(tbuf + 1, &ypcnt, sizeof(cnt));
398 				ypcnt++;
399 				key.size = sizeof(cnt) + 1;
400 				if ((dp->put)(dp, &key, &data, method) == -1)
401 					error("put");
402 				if ((sdp->put)(sdp, &key, &sdata, method) == -1)
403 					error("put");
404 			}
405 		}
406 		/* Create original format password file entry */
407 		if (is_comment && makeold){	/* copy comments */
408 			if (fprintf(oldfp, "%s\n", line) < 0)
409 				error("write old");
410 		} else if (makeold) {
411 			char uidstr[20];
412 			char gidstr[20];
413 
414 			snprintf(uidstr, sizeof(uidstr), "%u", pwd.pw_uid);
415 			snprintf(gidstr, sizeof(gidstr), "%u", pwd.pw_gid);
416 
417 			if (fprintf(oldfp, "%s:*:%s:%s:%s:%s:%s\n",
418 			    pwd.pw_name, pwd.pw_fields & _PWF_UID ? uidstr : "",
419 			    pwd.pw_fields & _PWF_GID ? gidstr : "",
420 			    pwd.pw_gecos, pwd.pw_dir, pwd.pw_shell) < 0)
421 				error("write old");
422 		}
423 	}
424 	/* If YP enabled, set flag. */
425 	if (yp_enabled) {
426 		buf[0] = yp_enabled + 2;
427 		data.size = 1;
428 		tbuf[0] = _PW_KEYYPENABLED;
429 		key.size = 1;
430 		if ((dp->put)(dp, &key, &data, method) == -1)
431 			error("put");
432 		if ((sdp->put)(sdp, &key, &data, method) == -1)
433 			error("put");
434 	}
435 
436 	if ((dp->close)(dp) == -1)
437 		error("close");
438 	if ((sdp->close)(sdp) == -1)
439 		error("close");
440 	if (makeold) {
441 		(void)fflush(oldfp);
442 		if (fclose(oldfp) == EOF)
443 			error("close old");
444 	}
445 
446 	/* Set master.passwd permissions, in case caller forgot. */
447 	(void)fchmod(fileno(fp), S_IRUSR|S_IWUSR);
448 
449 	/* Install as the real password files. */
450 	(void)snprintf(buf, sizeof(buf), "%s/%s.tmp", prefix, _MP_DB);
451 	(void)snprintf(buf2, sizeof(buf2), "%s/%s", prefix, _MP_DB);
452 	mv(buf, buf2);
453 	(void)snprintf(buf, sizeof(buf), "%s/%s.tmp", prefix, _SMP_DB);
454 	(void)snprintf(buf2, sizeof(buf2), "%s/%s", prefix, _SMP_DB);
455 	mv(buf, buf2);
456 	if (makeold) {
457 		(void)snprintf(buf2, sizeof(buf2), "%s/%s", prefix, _PASSWD);
458 		(void)snprintf(buf, sizeof(buf), "%s.orig", pname);
459 		mv(buf, buf2);
460 	}
461 	/*
462 	 * Move the master password LAST -- chpass(1), passwd(1) and vipw(8)
463 	 * all use flock(2) on it to block other incarnations of themselves.
464 	 * The rename means that everything is unlocked, as the original file
465 	 * can no longer be accessed.
466 	 */
467 	(void)snprintf(buf, sizeof(buf), "%s/%s", prefix, _MASTERPASSWD);
468 	mv(pname, buf);
469 
470 	/*
471 	 * Close locked password file after rename()
472 	 */
473 	if (fclose(fp) == EOF)
474 		error("close fp");
475 
476 	exit(0);
477 }
478 
479 int
480 scan(fp, pw)
481 	FILE *fp;
482 	struct passwd *pw;
483 {
484 	static int lcnt;
485 	char *p;
486 
487 	if (!fgets(line, sizeof(line), fp))
488 		return (0);
489 	++lcnt;
490 	/*
491 	 * ``... if I swallow anything evil, put your fingers down my
492 	 * throat...''
493 	 *	-- The Who
494 	 */
495 	if (!(p = strchr(line, '\n'))) {
496 		warnx("line too long");
497 		goto fmt;
498 
499 	}
500 	*p = '\0';
501 
502 	/*
503 	 * Ignore comments: ^[ \t]*#
504 	 */
505 	for (p = line; *p != '\0'; p++)
506 		if (*p != ' ' && *p != '\t')
507 			break;
508 	if (*p == '#' || *p == '\0') {
509 		is_comment = 1;
510 		return(1);
511 	} else
512 		is_comment = 0;
513 
514 	if (!pw_scan(line, pw)) {
515 		warnx("at line #%d", lcnt);
516 fmt:		errno = EFTYPE;	/* XXX */
517 		error(pname);
518 	}
519 
520 	return (1);
521 }
522 
523 void
524 cp(from, to, mode)
525 	char *from, *to;
526 	mode_t mode;
527 {
528 	static char buf[MAXBSIZE];
529 	int from_fd, rcount, to_fd, wcount;
530 
531 	if ((from_fd = open(from, O_RDONLY, 0)) < 0)
532 		error(from);
533 	if ((to_fd = open(to, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0)
534 		error(to);
535 	while ((rcount = read(from_fd, buf, MAXBSIZE)) > 0) {
536 		wcount = write(to_fd, buf, rcount);
537 		if (rcount != wcount || wcount == -1) {
538 			int sverrno = errno;
539 
540 			(void)snprintf(buf, sizeof(buf), "%s to %s", from, to);
541 			errno = sverrno;
542 			error(buf);
543 		}
544 	}
545 	if (rcount < 0) {
546 		int sverrno = errno;
547 
548 		(void)snprintf(buf, sizeof(buf), "%s to %s", from, to);
549 		errno = sverrno;
550 		error(buf);
551 	}
552 }
553 
554 
555 void
556 mv(from, to)
557 	char *from, *to;
558 {
559 	char buf[MAXPATHLEN];
560 
561 	if (rename(from, to)) {
562 		int sverrno = errno;
563 		(void)snprintf(buf, sizeof(buf), "%s to %s", from, to);
564 		errno = sverrno;
565 		error(buf);
566 	}
567 }
568 
569 void
570 error(name)
571 	char *name;
572 {
573 
574 	warn("%s", name);
575 	cleanup();
576 	exit(1);
577 }
578 
579 void
580 cleanup()
581 {
582 	char buf[MAXPATHLEN];
583 
584 	switch(clean) {
585 	case FILE_ORIG:
586 		(void)snprintf(buf, sizeof(buf), "%s.orig", pname);
587 		(void)unlink(buf);
588 		/* FALLTHROUGH */
589 	case FILE_SECURE:
590 		(void)snprintf(buf, sizeof(buf), "%s/%s.tmp", prefix, _SMP_DB);
591 		(void)unlink(buf);
592 		/* FALLTHROUGH */
593 	case FILE_INSECURE:
594 		(void)snprintf(buf, sizeof(buf), "%s/%s.tmp", prefix, _MP_DB);
595 		(void)unlink(buf);
596 	}
597 }
598 
599 static void
600 usage()
601 {
602 
603 	(void)fprintf(stderr,
604 "usage: pwd_mkdb [-C] [-N] [-p] [-d <dest dir>] [-s <cachesize>] [-u <local username>] file\n");
605 	exit(1);
606 }
607