xref: /freebsd/lib/libc/gen/getpwent.c (revision 3d238d9e981227b3bf739a51281e5d200bff3f8c)
1 /*-
2  * Copyright (c) 2003 Networks Associates Technology, Inc.
3  * All rights reserved.
4  *
5  * This software was developed for the FreeBSD Project by
6  * Jacques A. Vidrine, Safeport Network Services, and Network
7  * Associates Laboratories, the Security Research Division of Network
8  * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035
9  * ("CBOSS"), as part of the DARPA CHATS research program.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  */
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include "namespace.h"
37 #include <sys/param.h>
38 #ifdef YP
39 #include <rpc/rpc.h>
40 #include <rpcsvc/yp_prot.h>
41 #include <rpcsvc/ypclnt.h>
42 #endif
43 #include <arpa/inet.h>
44 #include <errno.h>
45 #include <fcntl.h>
46 #ifdef HESIOD
47 #include <hesiod.h>
48 #endif
49 #include <netdb.h>
50 #include <nsswitch.h>
51 #include <pthread.h>
52 #include <pthread_np.h>
53 #include <pwd.h>
54 #include <stdlib.h>
55 #include <stdio.h>
56 #include <string.h>
57 #include <syslog.h>
58 #include <unistd.h>
59 #include "un-namespace.h"
60 #include <db.h>
61 #include "libc_private.h"
62 #include "pw_scan.h"
63 #include "nss_tls.h"
64 
65 #ifndef CTASSERT
66 #define CTASSERT(x)		_CTASSERT(x, __LINE__)
67 #define _CTASSERT(x, y)		__CTASSERT(x, y)
68 #define __CTASSERT(x, y)	typedef char __assert_ ## y [(x) ? 1 : -1]
69 #endif
70 
71 /* Counter as stored in /etc/pwd.db */
72 typedef	int		pwkeynum;
73 
74 CTASSERT(MAXLOGNAME > sizeof(uid_t));
75 CTASSERT(MAXLOGNAME > sizeof(pwkeynum));
76 
77 enum constants {
78 	PWD_STORAGE_INITIAL	= 1 << 10, /* 1 KByte */
79 	PWD_STORAGE_MAX		= 1 << 20, /* 1 MByte */
80 	SETPWENT		= 1,
81 	ENDPWENT		= 2,
82 	HESIOD_NAME_MAX		= 256
83 };
84 
85 static const ns_src defaultsrc[] = {
86 	{ NSSRC_COMPAT, NS_SUCCESS },
87 	{ NULL, 0 }
88 };
89 
90 int	__pw_match_entry(const char *, size_t, enum nss_lookup_type,
91 	    const char *, uid_t);
92 int	__pw_parse_entry(char *, size_t, struct passwd *, int, int *errnop);
93 
94 static	void	 pwd_init(struct passwd *);
95 
96 union key {
97 	const char	*name;
98 	uid_t		 uid;
99 };
100 
101 static	struct passwd *getpw(int (*fn)(union key, struct passwd *, char *,
102 		    size_t, struct passwd **), union key);
103 static	int	 wrap_getpwnam_r(union key, struct passwd *, char *,
104 		    size_t, struct passwd **);
105 static	int	 wrap_getpwuid_r(union key, struct passwd *, char *, size_t,
106 		    struct passwd **);
107 static	int	 wrap_getpwent_r(union key, struct passwd *, char *, size_t,
108 		    struct passwd **);
109 
110 static	int	 pwdb_match_entry_v3(char *, size_t, enum nss_lookup_type,
111 		    const char *, uid_t);
112 static	int	 pwdb_parse_entry_v3(char *, size_t, struct passwd *, int *);
113 static	int	 pwdb_match_entry_v4(char *, size_t, enum nss_lookup_type,
114 		    const char *, uid_t);
115 static	int	 pwdb_parse_entry_v4(char *, size_t, struct passwd *, int *);
116 
117 
118 struct {
119 	int	(*match)(char *, size_t, enum nss_lookup_type, const char *,
120 		    uid_t);
121 	int	(*parse)(char *, size_t, struct passwd *, int *);
122 } pwdb_versions[] = {
123 	{ NULL, NULL },					/* version 0 */
124 	{ NULL, NULL },					/* version 1 */
125 	{ NULL, NULL },					/* version 2 */
126 	{ pwdb_match_entry_v3, pwdb_parse_entry_v3 },	/* version 3 */
127 	{ pwdb_match_entry_v4, pwdb_parse_entry_v4 },	/* version 4 */
128 };
129 
130 
131 struct files_state {
132 	DB		*db;
133 	pwkeynum	 keynum;
134 	int		 stayopen;
135 	int		 version;
136 };
137 static	void	files_endstate(void *);
138 NSS_TLS_HANDLING(files);
139 static	DB	*pwdbopen(int *);
140 static	void	 files_endstate(void *);
141 static	int	 files_setpwent(void *, void *, va_list);
142 static	int	 files_passwd(void *, void *, va_list);
143 
144 
145 #ifdef HESIOD
146 struct dns_state {
147 	long	counter;
148 };
149 static	void	dns_endstate(void *);
150 NSS_TLS_HANDLING(dns);
151 static	int	 dns_setpwent(void *, void *, va_list);
152 static	int	 dns_passwd(void *, void *, va_list);
153 #endif
154 
155 
156 #ifdef YP
157 struct nis_state {
158 	char	 domain[MAXHOSTNAMELEN];
159 	int	 done;
160 	char	*key;
161 	int	 keylen;
162 };
163 static	void	 nis_endstate(void *);
164 NSS_TLS_HANDLING(nis);
165 static	int	 nis_setpwent(void *, void *, va_list);
166 static	int	 nis_passwd(void *, void *, va_list);
167 static	int	 nis_map(char *, enum nss_lookup_type, char *, size_t, int *);
168 static	int	 nis_adjunct(char *, const char *, char *, size_t);
169 #endif
170 
171 
172 struct compat_state {
173 	DB		*db;
174 	pwkeynum	 keynum;
175 	int		 stayopen;
176 	int		 version;
177 	DB		*exclude;
178 	struct passwd	 template;
179 	char		*name;
180 	enum _compat {
181 		COMPAT_MODE_OFF = 0,
182 		COMPAT_MODE_ALL,
183 		COMPAT_MODE_NAME,
184 		COMPAT_MODE_NETGROUP
185 	}		 compat;
186 };
187 static	void	 compat_endstate(void *);
188 NSS_TLS_HANDLING(compat);
189 static	int	 compat_setpwent(void *, void *, va_list);
190 static	int	 compat_passwd(void *, void *, va_list);
191 static	void	 compat_clear_template(struct passwd *);
192 static	int	 compat_set_template(struct passwd *, struct passwd *);
193 static	int	 compat_use_template(struct passwd *, struct passwd *, char *,
194 		    size_t);
195 static	int	 compat_redispatch(struct compat_state *, enum nss_lookup_type,
196 		    enum nss_lookup_type, const char *, const char *, uid_t,
197 		    struct passwd *, char *, size_t, int *);
198 void
199 setpwent(void)
200 {
201 	static const ns_dtab dtab[] = {
202 		{ NSSRC_FILES, files_setpwent, (void *)SETPWENT },
203 #ifdef HESIOD
204 		{ NSSRC_DNS, dns_setpwent, (void *)SETPWENT },
205 #endif
206 #ifdef YP
207 		{ NSSRC_NIS, nis_setpwent, (void *)SETPWENT },
208 #endif
209 		{ NSSRC_COMPAT, compat_setpwent, (void *)SETPWENT },
210 		{ NULL, NULL, NULL }
211 	};
212 	(void)_nsdispatch(NULL, dtab, NSDB_PASSWD, "setpwent", defaultsrc, 0);
213 }
214 
215 
216 int
217 setpassent(int stayopen)
218 {
219 	static const ns_dtab dtab[] = {
220 		{ NSSRC_FILES, files_setpwent, (void *)SETPWENT },
221 #ifdef HESIOD
222 		{ NSSRC_DNS, dns_setpwent, (void *)SETPWENT },
223 #endif
224 #ifdef YP
225 		{ NSSRC_NIS, nis_setpwent, (void *)SETPWENT },
226 #endif
227 		{ NSSRC_COMPAT, compat_setpwent, (void *)SETPWENT },
228 		{ NULL, NULL, NULL }
229 	};
230 	(void)_nsdispatch(NULL, dtab, NSDB_PASSWD, "setpwent", defaultsrc,
231 	    stayopen);
232 	return (1);
233 }
234 
235 
236 void
237 endpwent(void)
238 {
239 	static const ns_dtab dtab[] = {
240 		{ NSSRC_FILES, files_setpwent, (void *)ENDPWENT },
241 #ifdef HESIOD
242 		{ NSSRC_DNS, dns_setpwent, (void *)ENDPWENT },
243 #endif
244 #ifdef YP
245 		{ NSSRC_NIS, nis_setpwent, (void *)ENDPWENT },
246 #endif
247 		{ NSSRC_COMPAT, compat_setpwent, (void *)ENDPWENT },
248 		{ NULL, NULL, NULL }
249 	};
250 	(void)_nsdispatch(NULL, dtab, NSDB_PASSWD, "endpwent", defaultsrc);
251 }
252 
253 
254 int
255 getpwent_r(struct passwd *pwd, char *buffer, size_t bufsize,
256     struct passwd **result)
257 {
258 	static const ns_dtab dtab[] = {
259 		{ NSSRC_FILES, files_passwd, (void *)nss_lt_all },
260 #ifdef HESIOD
261 		{ NSSRC_DNS, dns_passwd, (void *)nss_lt_all },
262 #endif
263 #ifdef YP
264 		{ NSSRC_NIS, nis_passwd, (void *)nss_lt_all },
265 #endif
266 		{ NSSRC_COMPAT, compat_passwd, (void *)nss_lt_all },
267 		{ NULL, NULL, NULL }
268 	};
269 	int	rv, ret_errno;
270 
271 	pwd_init(pwd);
272 	ret_errno = 0;
273 	*result = NULL;
274 	rv = _nsdispatch(result, dtab, NSDB_PASSWD, "getpwent_r", defaultsrc,
275 	    pwd, buffer, bufsize, &ret_errno);
276 	if (rv == NS_SUCCESS)
277 		return (0);
278 	else
279 		return (ret_errno);
280 }
281 
282 
283 int
284 getpwnam_r(const char *name, struct passwd *pwd, char *buffer, size_t bufsize,
285     struct passwd **result)
286 {
287 	static const ns_dtab dtab[] = {
288 		{ NSSRC_FILES, files_passwd, (void *)nss_lt_name },
289 #ifdef HESIOD
290 		{ NSSRC_DNS, dns_passwd, (void *)nss_lt_name },
291 #endif
292 #ifdef YP
293 		{ NSSRC_NIS, nis_passwd, (void *)nss_lt_name },
294 #endif
295 		{ NSSRC_COMPAT, compat_passwd, (void *)nss_lt_name },
296 		{ NULL, NULL, NULL }
297 	};
298 	int	rv, ret_errno;
299 
300 	pwd_init(pwd);
301 	ret_errno = 0;
302 	*result = NULL;
303 	rv = _nsdispatch(result, dtab, NSDB_PASSWD, "getpwnam_r", defaultsrc,
304 	    name, pwd, buffer, bufsize, &ret_errno);
305 	if (rv == NS_SUCCESS)
306 		return (0);
307 	else
308 		return (ret_errno);
309 }
310 
311 
312 int
313 getpwuid_r(uid_t uid, struct passwd *pwd, char *buffer, size_t bufsize,
314     struct passwd **result)
315 {
316 	static const ns_dtab dtab[] = {
317 		{ NSSRC_FILES, files_passwd, (void *)nss_lt_id },
318 #ifdef HESIOD
319 		{ NSSRC_DNS, dns_passwd, (void *)nss_lt_id },
320 #endif
321 #ifdef YP
322 		{ NSSRC_NIS, nis_passwd, (void *)nss_lt_id },
323 #endif
324 		{ NSSRC_COMPAT, compat_passwd, (void *)nss_lt_id },
325 		{ NULL, NULL, NULL }
326 	};
327 	int	rv, ret_errno;
328 
329 	pwd_init(pwd);
330 	ret_errno = 0;
331 	*result = NULL;
332 	rv = _nsdispatch(result, dtab, NSDB_PASSWD, "getpwuid_r", defaultsrc,
333 	    uid, pwd, buffer, bufsize, &ret_errno);
334 	if (rv == NS_SUCCESS)
335 		return (0);
336 	else
337 		return (ret_errno);
338 }
339 
340 
341 static void
342 pwd_init(struct passwd *pwd)
343 {
344 	static char nul[] = "";
345 
346 	memset(pwd, 0, sizeof(*pwd));
347 	pwd->pw_uid = (uid_t)-1;  /* Considered least likely to lead to */
348 	pwd->pw_gid = (gid_t)-1;  /* a security issue.                  */
349 	pwd->pw_name = nul;
350 	pwd->pw_passwd = nul;
351 	pwd->pw_class = nul;
352 	pwd->pw_gecos = nul;
353 	pwd->pw_dir = nul;
354 	pwd->pw_shell = nul;
355 }
356 
357 
358 static struct passwd	 pwd;
359 static char		*pwd_storage;
360 static size_t		 pwd_storage_size;
361 
362 
363 static struct passwd *
364 getpw(int (*fn)(union key, struct passwd *, char *, size_t, struct passwd **),
365     union key key)
366 {
367 	int		 rv;
368 	struct passwd	*res;
369 
370 	if (pwd_storage == NULL) {
371 		pwd_storage = malloc(PWD_STORAGE_INITIAL);
372 		if (pwd_storage == NULL)
373 			return (NULL);
374 		pwd_storage_size = PWD_STORAGE_INITIAL;
375 	}
376 	do {
377 		rv = fn(key, &pwd, pwd_storage, pwd_storage_size, &res);
378 		if (res == NULL && rv == ERANGE) {
379 			free(pwd_storage);
380 			if ((pwd_storage_size << 1) > PWD_STORAGE_MAX) {
381 				pwd_storage = NULL;
382 				return (NULL);
383 			}
384 			pwd_storage_size <<= 1;
385 			pwd_storage = malloc(pwd_storage_size);
386 			if (pwd_storage == NULL)
387 				return (NULL);
388 		}
389 	} while (res == NULL && rv == ERANGE);
390 	return (res);
391 }
392 
393 
394 static int
395 wrap_getpwnam_r(union key key, struct passwd *pwd, char *buffer,
396     size_t bufsize, struct passwd **res)
397 {
398 	return (getpwnam_r(key.name, pwd, buffer, bufsize, res));
399 }
400 
401 
402 static int
403 wrap_getpwuid_r(union key key, struct passwd *pwd, char *buffer,
404     size_t bufsize, struct passwd **res)
405 {
406 	return (getpwuid_r(key.uid, pwd, buffer, bufsize, res));
407 }
408 
409 
410 static int
411 wrap_getpwent_r(union key key __unused, struct passwd *pwd, char *buffer,
412     size_t bufsize, struct passwd **res)
413 {
414 	return (getpwent_r(pwd, buffer, bufsize, res));
415 }
416 
417 
418 struct passwd *
419 getpwnam(const char *name)
420 {
421 	union key key;
422 
423 	key.name = name;
424 	return (getpw(wrap_getpwnam_r, key));
425 }
426 
427 
428 struct passwd *
429 getpwuid(uid_t uid)
430 {
431 	union key key;
432 
433 	key.uid = uid;
434 	return (getpw(wrap_getpwuid_r, key));
435 }
436 
437 
438 struct passwd *
439 getpwent(void)
440 {
441 	union key key;
442 
443 	key.uid = 0; /* not used */
444 	return (getpw(wrap_getpwent_r, key));
445 }
446 
447 
448 /*
449  * files backend
450  */
451 static DB *
452 pwdbopen(int *version)
453 {
454 	DB	*res;
455 	DBT	 key, entry;
456 	int	 rv;
457 
458 	if (geteuid() != 0 ||
459 	    (res = dbopen(_PATH_SMP_DB, O_RDONLY, 0, DB_HASH, NULL)) == NULL)
460 		res = dbopen(_PATH_MP_DB, O_RDONLY, 0, DB_HASH, NULL);
461 	if (res == NULL)
462 		return (NULL);
463 	key.data = _PWD_VERSION_KEY;
464 	key.size = strlen(_PWD_VERSION_KEY);
465 	rv = res->get(res, &key, &entry, 0);
466 	if (rv == 0)
467 		*version = *(unsigned char *)entry.data;
468 	else
469 		*version = 3;
470 	if (*version < 3 ||
471 	    *version >= sizeof(pwdb_versions)/sizeof(pwdb_versions[0])) {
472 		syslog(LOG_CRIT, "Unsupported password database version %d",
473 		    *version);
474 		res->close(res);
475 		res = NULL;
476 	}
477 	return (res);
478 }
479 
480 
481 static void
482 files_endstate(void *p)
483 {
484 	DB	*db;
485 
486 	if (p == NULL)
487 		return;
488 	db = ((struct files_state *)p)->db;
489 	if (db != NULL)
490 		db->close(db);
491 	free(p);
492 }
493 
494 
495 static int
496 files_setpwent(void *retval, void *mdata, va_list ap)
497 {
498 	struct files_state	*st;
499 	int			 rv, stayopen;
500 
501 	rv = files_getstate(&st);
502 	if (rv != 0)
503 		return (NS_UNAVAIL);
504 	switch ((enum constants)mdata) {
505 	case SETPWENT:
506 		stayopen = va_arg(ap, int);
507 		st->keynum = 0;
508 		if (stayopen)
509 			st->db = pwdbopen(&st->version);
510 		st->stayopen = stayopen;
511 		break;
512 	case ENDPWENT:
513 		if (st->db != NULL) {
514 			(void)st->db->close(st->db);
515 			st->db = NULL;
516 		}
517 		break;
518 	default:
519 		break;
520 	}
521 	return (NS_UNAVAIL);
522 }
523 
524 
525 static int
526 files_passwd(void *retval, void *mdata, va_list ap)
527 {
528 	char			 keybuf[MAXLOGNAME + 1];
529 	DBT			 key, entry;
530 	struct files_state	*st;
531 	enum nss_lookup_type	 how;
532 	const char		*name;
533 	struct passwd		*pwd;
534 	char			*buffer;
535 	size_t			 bufsize, namesize;
536 	uid_t			 uid;
537 	uint32_t		 store;
538 	int			 rv, stayopen, *errnop;
539 
540 	name = NULL;
541 	uid = (uid_t)-1;
542 	how = (enum nss_lookup_type)mdata;
543 	switch (how) {
544 	case nss_lt_name:
545 		name = va_arg(ap, const char *);
546 		keybuf[0] = _PW_KEYBYNAME;
547 		break;
548 	case nss_lt_id:
549 		uid = va_arg(ap, uid_t);
550 		keybuf[0] = _PW_KEYBYUID;
551 		break;
552 	case nss_lt_all:
553 		keybuf[0] = _PW_KEYBYNUM;
554 		break;
555 	default:
556 		rv = NS_NOTFOUND;
557 		goto fin;
558 	}
559 	pwd = va_arg(ap, struct passwd *);
560 	buffer = va_arg(ap, char *);
561 	bufsize = va_arg(ap, size_t);
562 	errnop = va_arg(ap, int *);
563 	*errnop = files_getstate(&st);
564 	if (*errnop != 0)
565 		return (NS_UNAVAIL);
566 	if (how == nss_lt_all && st->keynum < 0) {
567 		rv = NS_NOTFOUND;
568 		goto fin;
569 	}
570 	if (st->db == NULL &&
571 	    (st->db = pwdbopen(&st->version)) == NULL) {
572 		*errnop = errno;
573 		rv = NS_UNAVAIL;
574 		goto fin;
575 	}
576 	if (how == nss_lt_all)
577 		stayopen = 1;
578 	else
579 		stayopen = st->stayopen;
580 	key.data = keybuf;
581 	do {
582 		switch (how) {
583 		case nss_lt_name:
584 			/* MAXLOGNAME includes NUL byte, but we do not
585 			 * include the NUL byte in the key.
586 			 */
587 			namesize = strlcpy(&keybuf[1], name, sizeof(keybuf)-1);
588 			if (namesize >= sizeof(keybuf)-1) {
589 				*errnop = EINVAL;
590 				rv = NS_NOTFOUND;
591 				goto fin;
592 			}
593 			key.size = namesize + 1;
594 			break;
595 		case nss_lt_id:
596 			if (st->version < _PWD_CURRENT_VERSION) {
597 				memcpy(&keybuf[1], &uid, sizeof(uid));
598 				key.size = sizeof(uid) + 1;
599 			} else {
600 				store = htonl(uid);
601 				memcpy(&keybuf[1], &store, sizeof(store));
602 				key.size = sizeof(store) + 1;
603 			}
604 			break;
605 		case nss_lt_all:
606 			st->keynum++;
607 			if (st->version < _PWD_CURRENT_VERSION) {
608 				memcpy(&keybuf[1], &st->keynum,
609 				    sizeof(st->keynum));
610 				key.size = sizeof(st->keynum) + 1;
611 			} else {
612 				store = htonl(st->keynum);
613 				memcpy(&keybuf[1], &store, sizeof(store));
614 				key.size = sizeof(store) + 1;
615 			}
616 			break;
617 		}
618 		keybuf[0] = _PW_VERSIONED(keybuf[0], st->version);
619 		rv = st->db->get(st->db, &key, &entry, 0);
620 		if (rv < 0 || rv > 1) { /* should never return > 1 */
621 			*errnop = errno;
622 			rv = NS_UNAVAIL;
623 			goto fin;
624 		} else if (rv == 1) {
625 			if (how == nss_lt_all)
626 				st->keynum = -1;
627 			rv = NS_NOTFOUND;
628 			goto fin;
629 		}
630 		rv = pwdb_versions[st->version].match(entry.data, entry.size,
631 		    how, name, uid);
632 		if (rv != NS_SUCCESS)
633 			continue;
634 		if (entry.size > bufsize) {
635 			*errnop = ERANGE;
636 			rv = NS_RETURN;
637 			break;
638 		}
639 		memcpy(buffer, entry.data, entry.size);
640 		rv = pwdb_versions[st->version].parse(buffer, entry.size, pwd,
641 		    errnop);
642 	} while (how == nss_lt_all && !(rv & NS_TERMINATE));
643 fin:
644 	if (!stayopen && st->db != NULL) {
645 		(void)st->db->close(st->db);
646 		st->db = NULL;
647 	}
648 	if (rv == NS_SUCCESS) {
649 		pwd->pw_fields &= ~_PWF_SOURCE;
650 		pwd->pw_fields |= _PWF_FILES;
651 		if (retval != NULL)
652 			*(struct passwd **)retval = pwd;
653 	}
654 	return (rv);
655 }
656 
657 
658 static int
659 pwdb_match_entry_v3(char *entry, size_t entrysize, enum nss_lookup_type how,
660     const char *name, uid_t uid)
661 {
662 	const char	*p, *eom;
663 	uid_t		 uid2;
664 
665 	eom = &entry[entrysize];
666 	for (p = entry; p < eom; p++)
667 		if (*p == '\0')
668 			break;
669 	if (*p != '\0')
670 		return (NS_NOTFOUND);
671 	if (how == nss_lt_all)
672 		return (NS_SUCCESS);
673 	if (how == nss_lt_name)
674 		return (strcmp(name, entry) == 0 ? NS_SUCCESS : NS_NOTFOUND);
675 	for (p++; p < eom; p++)
676 		if (*p == '\0')
677 			break;
678 	if (*p != '\0' || (++p) + sizeof(uid) >= eom)
679 		return (NS_NOTFOUND);
680 	memcpy(&uid2, p, sizeof(uid2));
681 	return (uid == uid2 ? NS_SUCCESS : NS_NOTFOUND);
682 }
683 
684 
685 static int
686 pwdb_parse_entry_v3(char *buffer, size_t bufsize, struct passwd *pwd,
687     int *errnop)
688 {
689 	char		*p, *eom;
690 	int32_t		 pw_change, pw_expire;
691 
692 	/* THIS CODE MUST MATCH THAT IN pwd_mkdb. */
693 	p = buffer;
694 	eom = &buffer[bufsize];
695 #define STRING(field)	do {			\
696 		(field) = p;			\
697 		while (p < eom && *p != '\0')	\
698 			p++;			\
699 		if (p >= eom)			\
700 			return (NS_NOTFOUND);	\
701 		p++;				\
702 	} while (0)
703 #define SCALAR(field)	do {				\
704 		if (p + sizeof(field) > eom)		\
705 			return (NS_NOTFOUND);		\
706 		memcpy(&(field), p, sizeof(field));	\
707 		p += sizeof(field);			\
708 	} while (0)
709 	STRING(pwd->pw_name);
710 	STRING(pwd->pw_passwd);
711 	SCALAR(pwd->pw_uid);
712 	SCALAR(pwd->pw_gid);
713 	SCALAR(pw_change);
714 	STRING(pwd->pw_class);
715 	STRING(pwd->pw_gecos);
716 	STRING(pwd->pw_dir);
717 	STRING(pwd->pw_shell);
718 	SCALAR(pw_expire);
719 	SCALAR(pwd->pw_fields);
720 #undef STRING
721 #undef SCALAR
722 	pwd->pw_change = pw_change;
723 	pwd->pw_expire = pw_expire;
724 	return (NS_SUCCESS);
725 }
726 
727 
728 static int
729 pwdb_match_entry_v4(char *entry, size_t entrysize, enum nss_lookup_type how,
730     const char *name, uid_t uid)
731 {
732 	const char	*p, *eom;
733 	uint32_t	 uid2;
734 
735 	eom = &entry[entrysize];
736 	for (p = entry; p < eom; p++)
737 		if (*p == '\0')
738 			break;
739 	if (*p != '\0')
740 		return (NS_NOTFOUND);
741 	if (how == nss_lt_all)
742 		return (NS_SUCCESS);
743 	if (how == nss_lt_name)
744 		return (strcmp(name, entry) == 0 ? NS_SUCCESS : NS_NOTFOUND);
745 	for (p++; p < eom; p++)
746 		if (*p == '\0')
747 			break;
748 	if (*p != '\0' || (++p) + sizeof(uid) >= eom)
749 		return (NS_NOTFOUND);
750 	memcpy(&uid2, p, sizeof(uid2));
751 	uid2 = ntohl(uid2);
752 	return (uid == (uid_t)uid2 ? NS_SUCCESS : NS_NOTFOUND);
753 }
754 
755 
756 static int
757 pwdb_parse_entry_v4(char *buffer, size_t bufsize, struct passwd *pwd,
758     int *errnop)
759 {
760 	char		*p, *eom;
761 	uint32_t	 n;
762 
763 	/* THIS CODE MUST MATCH THAT IN pwd_mkdb. */
764 	p = buffer;
765 	eom = &buffer[bufsize];
766 #define STRING(field)	do {			\
767 		(field) = p;			\
768 		while (p < eom && *p != '\0')	\
769 			p++;			\
770 		if (p >= eom)			\
771 			return (NS_NOTFOUND);	\
772 		p++;				\
773 	} while (0)
774 #define SCALAR(field)	do {				\
775 		if (p + sizeof(n) > eom)		\
776 			return (NS_NOTFOUND);		\
777 		memcpy(&n, p, sizeof(n));		\
778 		(field) = ntohl(n);			\
779 		p += sizeof(n);				\
780 	} while (0)
781 	STRING(pwd->pw_name);
782 	STRING(pwd->pw_passwd);
783 	SCALAR(pwd->pw_uid);
784 	SCALAR(pwd->pw_gid);
785 	SCALAR(pwd->pw_change);
786 	STRING(pwd->pw_class);
787 	STRING(pwd->pw_gecos);
788 	STRING(pwd->pw_dir);
789 	STRING(pwd->pw_shell);
790 	SCALAR(pwd->pw_expire);
791 	SCALAR(pwd->pw_fields);
792 #undef STRING
793 #undef SCALAR
794 	return (NS_SUCCESS);
795 }
796 
797 
798 #ifdef HESIOD
799 /*
800  * dns backend
801  */
802 static void
803 dns_endstate(void *p)
804 {
805 	free(p);
806 }
807 
808 
809 static int
810 dns_setpwent(void *retval, void *mdata, va_list ap)
811 {
812 	struct dns_state	*st;
813 	int			 rv;
814 
815 	rv = dns_getstate(&st);
816 	if (rv != 0)
817 		return (NS_UNAVAIL);
818 	st->counter = 0;
819 	return (NS_UNAVAIL);
820 }
821 
822 
823 static int
824 dns_passwd(void *retval, void *mdata, va_list ap)
825 {
826 	char			 buf[HESIOD_NAME_MAX];
827 	struct dns_state	*st;
828 	struct passwd		*pwd;
829 	const char		*name, *label;
830 	void			*ctx;
831 	char			*buffer, **hes;
832 	size_t			 bufsize, linesize;
833 	uid_t			 uid;
834 	enum nss_lookup_type	 how;
835 	int			 rv, *errnop;
836 
837 	ctx = NULL;
838 	hes = NULL;
839 	name = NULL;
840 	uid = (uid_t)-1;
841 	how = (enum nss_lookup_type)mdata;
842 	switch (how) {
843 	case nss_lt_name:
844 		name = va_arg(ap, const char *);
845 		break;
846 	case nss_lt_id:
847 		uid = va_arg(ap, uid_t);
848 		break;
849 	case nss_lt_all:
850 		break;
851 	}
852 	pwd     = va_arg(ap, struct passwd *);
853 	buffer  = va_arg(ap, char *);
854 	bufsize = va_arg(ap, size_t);
855 	errnop  = va_arg(ap, int *);
856 	*errnop = dns_getstate(&st);
857 	if (*errnop != 0)
858 		return (NS_UNAVAIL);
859 	if (hesiod_init(&ctx) != 0) {
860 		*errnop = errno;
861 		rv = NS_UNAVAIL;
862 		goto fin;
863 	}
864 	do {
865 		rv = NS_NOTFOUND;
866 		switch (how) {
867 		case nss_lt_name:
868 			label = name;
869 			break;
870 		case nss_lt_id:
871 			if (snprintf(buf, sizeof(buf), "%lu",
872 			    (unsigned long)uid) >= sizeof(buf))
873 				goto fin;
874 			label = buf;
875 			break;
876 		case nss_lt_all:
877 			if (st->counter < 0)
878 				goto fin;
879 			if (snprintf(buf, sizeof(buf), "passwd-%ld",
880 			    st->counter++) >= sizeof(buf))
881 				goto fin;
882 			label = buf;
883 			break;
884 		}
885 		hes = hesiod_resolve(ctx, label,
886 		    how == nss_lt_id ? "uid" : "passwd");
887 		if (hes == NULL) {
888 			if (how == nss_lt_all)
889 				st->counter = -1;
890 			if (errno != ENOENT)
891 				*errnop = errno;
892 			goto fin;
893 		}
894 		rv = __pw_match_entry(hes[0], strlen(hes[0]), how, name, uid);
895 		if (rv != NS_SUCCESS) {
896 			hesiod_free_list(ctx, hes);
897 			hes = NULL;
898 			continue;
899 		}
900 		linesize = strlcpy(buffer, hes[0], bufsize);
901 		if (linesize >= bufsize) {
902 			*errnop = ERANGE;
903 			rv = NS_RETURN;
904 			continue;
905 		}
906 		hesiod_free_list(ctx, hes);
907 		hes = NULL;
908 		rv = __pw_parse_entry(buffer, bufsize, pwd, 0, errnop);
909 	} while (how == nss_lt_all && !(rv & NS_TERMINATE));
910 fin:
911 	if (hes != NULL)
912 		hesiod_free_list(ctx, hes);
913 	if (ctx != NULL)
914 		hesiod_end(ctx);
915 	if (rv == NS_SUCCESS) {
916 		pwd->pw_fields &= ~_PWF_SOURCE;
917 		pwd->pw_fields |= _PWF_HESIOD;
918 		if (retval != NULL)
919 			*(struct passwd **)retval = pwd;
920 	}
921 	return (rv);
922 }
923 #endif /* HESIOD */
924 
925 
926 #ifdef YP
927 /*
928  * nis backend
929  */
930 static void
931 nis_endstate(void *p)
932 {
933 	free(((struct nis_state *)p)->key);
934 	free(p);
935 }
936 
937 static int
938 nis_map(char *domain, enum nss_lookup_type how, char *buffer, size_t bufsize,
939     int *master)
940 {
941 	int	rv;
942 	char	*outname;
943 
944 	*master = 0;
945 	if (geteuid() == 0) {
946 		if (snprintf(buffer, bufsize, "master.passwd.by%s",
947 		    (how == nss_lt_id) ? "uid" : "name") >= bufsize)
948 			return (NS_UNAVAIL);
949 		rv = yp_master(domain, buffer, &outname);
950 		if (rv == 0) {
951 			*master = 1;
952 			return (NS_SUCCESS);
953 		}
954 	}
955 	if (snprintf(buffer, bufsize, "passwd.by%s",
956 	    (how == nss_lt_id) ? "uid" : "name") >= bufsize)
957 		return (NS_UNAVAIL);
958 	rv = yp_master(domain, buffer, &outname);
959 	if (rv == 0)
960 		return (NS_SUCCESS);
961 	return (NS_UNAVAIL);
962 }
963 
964 
965 static int
966 nis_adjunct(char *domain, const char *name, char *buffer, size_t bufsize)
967 {
968 	int	 rv;
969 	char	*result, *p, *q, *eor;
970 	int	 resultlen;
971 
972 	result = NULL;
973 	rv = yp_match(domain, "passwd.adjunct.byname", name, strlen(name),
974 	    &result, &resultlen);
975 	if (rv != 0)
976 		rv = 1;
977 	else {
978 		eor = &result[resultlen];
979 		p = memchr(result, ':', eor - result);
980 		if (p != NULL && ++p < eor &&
981 		    (q = memchr(p, ':', eor - p)) != NULL) {
982 			if (q - p >= bufsize)
983 				rv = -1;
984 			else {
985 				memcpy(buffer, p, q - p);
986 				buffer[q - p] ='\0';
987 			}
988 		} else
989 			rv = 1;
990 	}
991 	free(result);
992 	return (rv);
993 }
994 
995 
996 static int
997 nis_setpwent(void *retval, void *mdata, va_list ap)
998 {
999 	struct nis_state	*st;
1000 	int			 rv;
1001 
1002 	rv = nis_getstate(&st);
1003 	if (rv != 0)
1004 		return (NS_UNAVAIL);
1005 	st->done = 0;
1006 	free(st->key);
1007 	st->key = NULL;
1008 	return (NS_UNAVAIL);
1009 }
1010 
1011 
1012 static int
1013 nis_passwd(void *retval, void *mdata, va_list ap)
1014 {
1015 	char		 map[YPMAXMAP];
1016 	struct nis_state *st;
1017 	struct passwd	*pwd;
1018 	const char	*name;
1019 	char		*buffer, *key, *result;
1020 	size_t		 bufsize;
1021 	uid_t		 uid;
1022 	enum nss_lookup_type how;
1023 	int		*errnop, keylen, resultlen, rv, master;
1024 
1025 	name = NULL;
1026 	uid = (uid_t)-1;
1027 	how = (enum nss_lookup_type)mdata;
1028 	switch (how) {
1029 	case nss_lt_name:
1030 		name = va_arg(ap, const char *);
1031 		break;
1032 	case nss_lt_id:
1033 		uid = va_arg(ap, uid_t);
1034 		break;
1035 	case nss_lt_all:
1036 		break;
1037 	}
1038 	pwd     = va_arg(ap, struct passwd *);
1039 	buffer  = va_arg(ap, char *);
1040 	bufsize = va_arg(ap, size_t);
1041 	errnop  = va_arg(ap, int *);
1042 	*errnop = nis_getstate(&st);
1043 	if (*errnop != 0)
1044 		return (NS_UNAVAIL);
1045 	if (st->domain[0] == '\0') {
1046 		if (getdomainname(st->domain, sizeof(st->domain)) != 0) {
1047 			*errnop = errno;
1048 			return (NS_UNAVAIL);
1049 		}
1050 	}
1051 	rv = nis_map(st->domain, how, map, sizeof(map), &master);
1052 	if (rv != NS_SUCCESS)
1053 		return (rv);
1054 	result = NULL;
1055 	do {
1056 		rv = NS_NOTFOUND;
1057 		switch (how) {
1058 		case nss_lt_name:
1059 			if (strlcpy(buffer, name, bufsize) >= bufsize)
1060 				goto erange;
1061 			break;
1062 		case nss_lt_id:
1063 			if (snprintf(buffer, bufsize, "%lu",
1064 			    (unsigned long)uid) >= bufsize)
1065 				goto erange;
1066 			break;
1067 		case nss_lt_all:
1068 			if (st->done)
1069 				goto fin;
1070 			break;
1071 		}
1072 		result = NULL;
1073 		if (how == nss_lt_all) {
1074 			if (st->key == NULL)
1075 				rv = yp_first(st->domain, map, &st->key,
1076 				    &st->keylen, &result, &resultlen);
1077 			else {
1078 				key = st->key;
1079 				keylen = st->keylen;
1080 				st->key = NULL;
1081 				rv = yp_next(st->domain, map, key, keylen,
1082 				    &st->key, &st->keylen, &result,
1083 				    &resultlen);
1084 				free(key);
1085 			}
1086 			if (rv != 0) {
1087 				free(result);
1088 				free(st->key);
1089 				st->key = NULL;
1090 				if (rv == YPERR_NOMORE)
1091 					st->done = 1;
1092 				else
1093 					rv = NS_UNAVAIL;
1094 				goto fin;
1095 			}
1096 		} else {
1097 			rv = yp_match(st->domain, map, buffer, strlen(buffer),
1098 			    &result, &resultlen);
1099 			if (rv == YPERR_KEY) {
1100 				rv = NS_NOTFOUND;
1101 				continue;
1102 			} else if (rv != 0) {
1103 				free(result);
1104 				rv = NS_UNAVAIL;
1105 				continue;
1106 			}
1107 		}
1108 		if (resultlen >= bufsize)
1109 			goto erange;
1110 		memcpy(buffer, result, resultlen);
1111 		buffer[resultlen] = '\0';
1112 		free(result);
1113 		rv = __pw_match_entry(buffer, resultlen, how, name, uid);
1114 		if (rv == NS_SUCCESS)
1115 			rv = __pw_parse_entry(buffer, resultlen, pwd, master,
1116 			    errnop);
1117 	} while (how == nss_lt_all && !(rv & NS_TERMINATE));
1118 fin:
1119 	if (rv == NS_SUCCESS) {
1120 		if (strstr(pwd->pw_passwd, "##") != NULL) {
1121 			rv = nis_adjunct(st->domain, name,
1122 			    &buffer[resultlen+1], bufsize-resultlen-1);
1123 			if (rv < 0)
1124 				goto erange;
1125 			else if (rv == 0)
1126 				pwd->pw_passwd = &buffer[resultlen+1];
1127 		}
1128 		pwd->pw_fields &= ~_PWF_SOURCE;
1129 		pwd->pw_fields |= _PWF_NIS;
1130 		if (retval != NULL)
1131 			*(struct passwd **)retval = pwd;
1132 	}
1133 	return (rv);
1134 erange:
1135 	*errnop = ERANGE;
1136 	return (NS_RETURN);
1137 }
1138 #endif /* YP */
1139 
1140 
1141 /*
1142  * compat backend
1143  */
1144 static void
1145 compat_clear_template(struct passwd *template)
1146 {
1147 
1148 	free(template->pw_passwd);
1149 	free(template->pw_gecos);
1150 	free(template->pw_dir);
1151 	free(template->pw_shell);
1152 	memset(template, 0, sizeof(*template));
1153 }
1154 
1155 
1156 static int
1157 compat_set_template(struct passwd *src, struct passwd *template)
1158 {
1159 
1160 	compat_clear_template(template);
1161 #ifdef PW_OVERRIDE_PASSWD
1162 	if ((src->pw_fields & _PWF_PASSWD) &&
1163 	    (template->pw_passwd = strdup(src->pw_passwd)) == NULL)
1164 		goto enomem;
1165 #endif
1166 	if (src->pw_fields & _PWF_UID)
1167 		template->pw_uid = src->pw_uid;
1168 	if (src->pw_fields & _PWF_GID)
1169 		template->pw_gid = src->pw_gid;
1170 	if ((src->pw_fields & _PWF_GECOS) &&
1171 	    (template->pw_gecos = strdup(src->pw_gecos)) == NULL)
1172 		goto enomem;
1173 	if ((src->pw_fields & _PWF_DIR) &&
1174 	    (template->pw_dir = strdup(src->pw_dir)) == NULL)
1175 		goto enomem;
1176 	if ((src->pw_fields & _PWF_SHELL) &&
1177 	    (template->pw_shell = strdup(src->pw_shell)) == NULL)
1178 		goto enomem;
1179 	template->pw_fields = src->pw_fields;
1180 	return (0);
1181 enomem:
1182 	syslog(LOG_ERR, "getpwent memory allocation failure");
1183 	return (-1);
1184 }
1185 
1186 
1187 static int
1188 compat_use_template(struct passwd *pwd, struct passwd *template, char *buffer,
1189     size_t bufsize)
1190 {
1191 	struct passwd hold;
1192 	char	*copy, *p, *q, *eob;
1193 	size_t	 n;
1194 
1195 	/* We cannot know the layout of the password fields in `buffer',
1196 	 * so we have to copy everything.
1197 	 */
1198 	if (template->pw_fields == 0) /* nothing to fill-in */
1199 		return (0);
1200 	n = 0;
1201 	n += pwd->pw_name != NULL ? strlen(pwd->pw_name) + 1 : 0;
1202 	n += pwd->pw_passwd != NULL ? strlen(pwd->pw_passwd) + 1 : 0;
1203 	n += pwd->pw_class != NULL ? strlen(pwd->pw_class) + 1 : 0;
1204 	n += pwd->pw_gecos != NULL ? strlen(pwd->pw_gecos) + 1 : 0;
1205 	n += pwd->pw_dir != NULL ? strlen(pwd->pw_dir) + 1 : 0;
1206 	n += pwd->pw_shell != NULL ? strlen(pwd->pw_shell) + 1 : 0;
1207 	copy = malloc(n);
1208 	if (copy == NULL) {
1209 		syslog(LOG_ERR, "getpwent memory allocation failure");
1210 		return (ENOMEM);
1211 	}
1212 	p = copy;
1213 	eob = &copy[n];
1214 #define COPY(field) do {				\
1215 	if (pwd->field == NULL)				\
1216 		hold.field = NULL;			\
1217 	else {						\
1218 		hold.field = p;				\
1219 		p += strlcpy(p, pwd->field, eob-p) + 1;	\
1220 	}						\
1221 } while (0)
1222 	COPY(pw_name);
1223 	COPY(pw_passwd);
1224 	COPY(pw_class);
1225 	COPY(pw_gecos);
1226 	COPY(pw_dir);
1227 	COPY(pw_shell);
1228 #undef COPY
1229 	p = buffer;
1230 	eob = &buffer[bufsize];
1231 #define COPY(field, flag) do {						 \
1232 	q = (template->pw_fields & flag) ? template->field : hold.field; \
1233 	if (q == NULL)							 \
1234 		pwd->field = NULL;					 \
1235 	else {								 \
1236 		pwd->field = p;						 \
1237 		if ((n = strlcpy(p, q, eob-p)) >= eob-p) {		 \
1238 			free(copy);					 \
1239 			return (ERANGE);				 \
1240 		}							 \
1241 		p += n + 1;						 \
1242 	}								 \
1243 } while (0)
1244 	COPY(pw_name, 0);
1245 #ifdef PW_OVERRIDE_PASSWD
1246 	COPY(pw_passwd, _PWF_PASSWD);
1247 #else
1248 	COPY(pw_passwd, 0);
1249 #endif
1250 	COPY(pw_class, 0);
1251 	COPY(pw_gecos, _PWF_GECOS);
1252 	COPY(pw_dir, _PWF_DIR);
1253 	COPY(pw_shell, _PWF_SHELL);
1254 #undef COPY
1255 #define COPY(field, flag) do {			\
1256 	if (template->pw_fields & flag)		\
1257 		pwd->field = template->field;	\
1258 } while (0)
1259 	COPY(pw_uid, _PWF_UID);
1260 	COPY(pw_gid, _PWF_GID);
1261 #undef COPY
1262 	free(copy);
1263 	return (0);
1264 }
1265 
1266 
1267 static int
1268 compat_exclude(const char *name, DB **db)
1269 {
1270 	DBT	key, data;
1271 
1272 	if (*db == NULL &&
1273 	    (*db = dbopen(NULL, O_RDWR, 600, DB_HASH, 0)) == NULL)
1274 		return (errno);
1275 	key.size = strlen(name);
1276 	key.data = (char *)name;
1277 	data.size = 0;
1278 	data.data = NULL;
1279 
1280 	if ((*db)->put(*db, &key, &data, 0) == -1)
1281 		return (errno);
1282 	return (0);
1283 }
1284 
1285 
1286 static int
1287 compat_is_excluded(const char *name, DB *db)
1288 {
1289 	DBT	key, data;
1290 
1291 	if (db == NULL)
1292 		return (0);
1293 	key.size = strlen(name);
1294 	key.data = (char *)name;
1295 	return (db->get(db, &key, &data, 0) == 0);
1296 }
1297 
1298 
1299 static int
1300 compat_redispatch(struct compat_state *st, enum nss_lookup_type how,
1301     enum nss_lookup_type lookup_how, const char *name, const char *lookup_name,
1302     uid_t uid, struct passwd *pwd, char *buffer, size_t bufsize, int *errnop)
1303 {
1304 	static const ns_src compatsrc[] = {
1305 #ifdef YP
1306 		{ NSSRC_NIS, NS_SUCCESS },
1307 #endif
1308 		{ NULL, 0 }
1309 	};
1310 	ns_dtab dtab[] = {
1311 #ifdef YP
1312 		{ NSSRC_NIS, nis_passwd, NULL },
1313 #endif
1314 #ifdef HESIOD
1315 		{ NSSRC_DNS, dns_passwd, NULL },
1316 #endif
1317 		{ NULL, NULL, NULL }
1318 	};
1319 	void		*discard;
1320 	int		 rv, e, i;
1321 
1322 	for (i = 0; i < sizeof(dtab)/sizeof(dtab[0]) - 1; i++)
1323 		dtab[i].mdata = (void *)lookup_how;
1324 more:
1325 	pwd_init(pwd);
1326 	switch (lookup_how) {
1327 	case nss_lt_all:
1328 		rv = _nsdispatch(&discard, dtab, NSDB_PASSWD_COMPAT,
1329 		    "getpwent_r", compatsrc, pwd, buffer, bufsize,
1330 		    errnop);
1331 		break;
1332 	case nss_lt_id:
1333 		rv = _nsdispatch(&discard, dtab, NSDB_PASSWD_COMPAT,
1334 		    "getpwuid_r", compatsrc, uid, pwd, buffer,
1335 		    bufsize, errnop);
1336 		break;
1337 	case nss_lt_name:
1338 		rv = _nsdispatch(&discard, dtab, NSDB_PASSWD_COMPAT,
1339 		    "getpwnam_r", compatsrc, lookup_name, pwd, buffer,
1340 		    bufsize, errnop);
1341 		break;
1342 	default:
1343 		return (NS_UNAVAIL);
1344 	}
1345 	if (rv != NS_SUCCESS)
1346 		return (rv);
1347 	if (compat_is_excluded(pwd->pw_name, st->exclude)) {
1348 		if (how == nss_lt_all)
1349 			goto more;
1350 		return (NS_NOTFOUND);
1351 	}
1352 	e = compat_use_template(pwd, &st->template, buffer, bufsize);
1353 	if (e != 0) {
1354 		*errnop = e;
1355 		if (e == ERANGE)
1356 			return (NS_RETURN);
1357 		else
1358 			return (NS_UNAVAIL);
1359 	}
1360 	switch (how) {
1361 	case nss_lt_name:
1362 		if (strcmp(name, pwd->pw_name) != 0)
1363 			return (NS_NOTFOUND);
1364 		break;
1365 	case nss_lt_id:
1366 		if (uid != pwd->pw_uid)
1367 			return (NS_NOTFOUND);
1368 		break;
1369 	default:
1370 		break;
1371 	}
1372 	return (NS_SUCCESS);
1373 }
1374 
1375 
1376 static void
1377 compat_endstate(void *p)
1378 {
1379 	struct compat_state *st;
1380 
1381 	if (p == NULL)
1382 		return;
1383 	st = (struct compat_state *)p;
1384 	if (st->db != NULL)
1385 		st->db->close(st->db);
1386 	if (st->exclude != NULL)
1387 		st->exclude->close(st->exclude);
1388 	compat_clear_template(&st->template);
1389 	free(p);
1390 }
1391 
1392 
1393 static int
1394 compat_setpwent(void *retval, void *mdata, va_list ap)
1395 {
1396 	static const ns_src compatsrc[] = {
1397 #ifdef YP
1398 		{ NSSRC_NIS, NS_SUCCESS },
1399 #endif
1400 		{ NULL, 0 }
1401 	};
1402 	ns_dtab dtab[] = {
1403 #ifdef YP
1404 		{ NSSRC_NIS, nis_setpwent, NULL },
1405 #endif
1406 #ifdef HESIOD
1407 		{ NSSRC_DNS, dns_setpwent, NULL },
1408 #endif
1409 		{ NULL, NULL, NULL }
1410 	};
1411 	struct compat_state	*st;
1412 	int			 rv, stayopen;
1413 
1414 #define set_setent(x, y) do {	 				\
1415 	int i;							\
1416 								\
1417 	for (i = 0; i < (sizeof(x)/sizeof(x[0])) - 1; i++)	\
1418 		x[i].mdata = (void *)y;				\
1419 } while (0)
1420 
1421 	rv = compat_getstate(&st);
1422 	if (rv != 0)
1423 		return (NS_UNAVAIL);
1424 	switch ((enum constants)mdata) {
1425 	case SETPWENT:
1426 		stayopen = va_arg(ap, int);
1427 		st->keynum = 0;
1428 		if (stayopen)
1429 			st->db = pwdbopen(&st->version);
1430 		st->stayopen = stayopen;
1431 		set_setent(dtab, mdata);
1432 		(void)_nsdispatch(NULL, dtab, NSDB_PASSWD_COMPAT, "setpwent",
1433 		    compatsrc, 0);
1434 		break;
1435 	case ENDPWENT:
1436 		if (st->db != NULL) {
1437 			(void)st->db->close(st->db);
1438 			st->db = NULL;
1439 		}
1440 		set_setent(dtab, mdata);
1441 		(void)_nsdispatch(NULL, dtab, NSDB_PASSWD_COMPAT, "endpwent",
1442 		    compatsrc, 0);
1443 		break;
1444 	default:
1445 		break;
1446 	}
1447 	return (NS_UNAVAIL);
1448 #undef set_setent
1449 }
1450 
1451 
1452 static int
1453 compat_passwd(void *retval, void *mdata, va_list ap)
1454 {
1455 	char			 keybuf[MAXLOGNAME + 1];
1456 	DBT			 key, entry;
1457 	struct compat_state	*st;
1458 	enum nss_lookup_type	 how;
1459 	const char		*name;
1460 	struct passwd		*pwd;
1461 	char			*buffer, *pw_name;
1462 	char			*host, *user, *domain;
1463 	size_t			 bufsize;
1464 	uid_t			 uid;
1465 	uint32_t		 store;
1466 	int			 rv, from_compat, stayopen, *errnop;
1467 
1468 	from_compat = 0;
1469 	name = NULL;
1470 	uid = (uid_t)-1;
1471 	how = (enum nss_lookup_type)mdata;
1472 	switch (how) {
1473 	case nss_lt_name:
1474 		name = va_arg(ap, const char *);
1475 		break;
1476 	case nss_lt_id:
1477 		uid = va_arg(ap, uid_t);
1478 		break;
1479 	case nss_lt_all:
1480 		break;
1481 	default:
1482 		rv = NS_NOTFOUND;
1483 		goto fin;
1484 	}
1485 	pwd = va_arg(ap, struct passwd *);
1486 	buffer = va_arg(ap, char *);
1487 	bufsize = va_arg(ap, size_t);
1488 	errnop = va_arg(ap, int *);
1489 	*errnop = compat_getstate(&st);
1490 	if (*errnop != 0)
1491 		return (NS_UNAVAIL);
1492 	if (how == nss_lt_all && st->keynum < 0) {
1493 		rv = NS_NOTFOUND;
1494 		goto fin;
1495 	}
1496 	if (st->db == NULL &&
1497 	    (st->db = pwdbopen(&st->version)) == NULL) {
1498 		*errnop = errno;
1499 		rv = NS_UNAVAIL;
1500 		goto fin;
1501 	}
1502 	if (how == nss_lt_all) {
1503 		if (st->keynum < 0) {
1504 			rv = NS_NOTFOUND;
1505 			goto fin;
1506 		}
1507 		stayopen = 1;
1508 	} else {
1509 		st->keynum = 0;
1510 		stayopen = st->stayopen;
1511 	}
1512 docompat:
1513 	rv = NS_NOTFOUND;
1514 	switch (st->compat) {
1515 	case COMPAT_MODE_ALL:
1516 		rv = compat_redispatch(st, how, how, name, name, uid, pwd,
1517 		    buffer, bufsize, errnop);
1518 		if (rv != NS_SUCCESS)
1519 			st->compat = COMPAT_MODE_OFF;
1520 		break;
1521 	case COMPAT_MODE_NETGROUP:
1522 		/* XXX getnetgrent is not thread-safe. */
1523 		do {
1524 			rv = getnetgrent(&host, &user, &domain);
1525 			if (rv == 0) {
1526 				endnetgrent();
1527 				st->compat = COMPAT_MODE_OFF;
1528 				rv = NS_NOTFOUND;
1529 				continue;
1530 			} else if (user == NULL || user[0] == '\0')
1531 				continue;
1532 			rv = compat_redispatch(st, how, nss_lt_name, name,
1533 			    user, uid, pwd, buffer, bufsize, errnop);
1534 		} while (st->compat == COMPAT_MODE_NETGROUP &&
1535 		    !(rv & NS_TERMINATE));
1536 		break;
1537 	case COMPAT_MODE_NAME:
1538 		rv = compat_redispatch(st, how, nss_lt_name, name, st->name,
1539 		    uid, pwd, buffer, bufsize, errnop);
1540 		free(st->name);
1541 		st->name = NULL;
1542 		st->compat = COMPAT_MODE_OFF;
1543 		break;
1544 	default:
1545 		break;
1546 	}
1547 	if (rv & NS_TERMINATE) {
1548 		from_compat = 1;
1549 		goto fin;
1550 	}
1551 	key.data = keybuf;
1552 	rv = NS_NOTFOUND;
1553 	while (st->keynum >= 0) {
1554 		st->keynum++;
1555 		if (st->version < _PWD_CURRENT_VERSION) {
1556 			memcpy(&keybuf[1], &st->keynum, sizeof(st->keynum));
1557 			key.size = sizeof(st->keynum) + 1;
1558 		} else {
1559 			store = htonl(st->keynum);
1560 			memcpy(&keybuf[1], &store, sizeof(store));
1561 			key.size = sizeof(store) + 1;
1562 		}
1563 		keybuf[0] = _PW_VERSIONED(_PW_KEYBYNUM, st->version);
1564 		rv = st->db->get(st->db, &key, &entry, 0);
1565 		if (rv < 0 || rv > 1) { /* should never return > 1 */
1566 			*errnop = errno;
1567 			rv = NS_UNAVAIL;
1568 			goto fin;
1569 		} else if (rv == 1) {
1570 			st->keynum = -1;
1571 			rv = NS_NOTFOUND;
1572 			goto fin;
1573 		}
1574 		pw_name = (char *)entry.data;
1575 		switch (pw_name[0]) {
1576 		case '+':
1577 			switch (pw_name[1]) {
1578 			case '\0':
1579 				st->compat = COMPAT_MODE_ALL;
1580 				break;
1581 			case '@':
1582 				setnetgrent(&pw_name[2]);
1583 				st->compat = COMPAT_MODE_NETGROUP;
1584 				break;
1585 			default:
1586 				st->name = strdup(&pw_name[1]);
1587 				if (st->name == NULL) {
1588 					syslog(LOG_ERR,
1589 					 "getpwent memory allocation failure");
1590 					*errnop = ENOMEM;
1591 					rv = NS_UNAVAIL;
1592 					break;
1593 				}
1594 				st->compat = COMPAT_MODE_NAME;
1595 			}
1596 			if (entry.size > bufsize) {
1597 				*errnop = ERANGE;
1598 				rv = NS_RETURN;
1599 				goto fin;
1600 			}
1601 			memcpy(buffer, entry.data, entry.size);
1602 			rv = pwdb_versions[st->version].parse(buffer,
1603 			    entry.size, pwd, errnop);
1604 			if (rv != NS_SUCCESS)
1605 				;
1606 			else if (compat_set_template(pwd, &st->template) < 0) {
1607 				*errnop = ENOMEM;
1608 				rv = NS_UNAVAIL;
1609 				goto fin;
1610 			}
1611 			goto docompat;
1612 		case '-':
1613 			switch (pw_name[1]) {
1614 			case '\0':
1615 				/* XXX Maybe syslog warning */
1616 				continue;
1617 			case '@':
1618 				setnetgrent(&pw_name[2]);
1619 				while (getnetgrent(&host, &user, &domain) !=
1620 				    NULL) {
1621 					if (user != NULL && user[0] != '\0')
1622 						compat_exclude(user,
1623 						    &st->exclude);
1624 				}
1625 				endnetgrent();
1626 				continue;
1627 			default:
1628 				compat_exclude(&pw_name[1], &st->exclude);
1629 				continue;
1630 			}
1631 			break;
1632 		default:
1633 			break;
1634 		}
1635 		if (compat_is_excluded((char *)entry.data, st->exclude))
1636 			continue;
1637 		rv = pwdb_versions[st->version].match(entry.data, entry.size,
1638 		    how, name, uid);
1639 		if (rv == NS_RETURN)
1640 			break;
1641 		else if (rv != NS_SUCCESS)
1642 			continue;
1643 		if (entry.size > bufsize) {
1644 			*errnop = ERANGE;
1645 			rv = NS_RETURN;
1646 			break;
1647 		}
1648 		memcpy(buffer, entry.data, entry.size);
1649 		rv = pwdb_versions[st->version].parse(buffer, entry.size, pwd,
1650 		    errnop);
1651 		if (rv & NS_TERMINATE)
1652 			break;
1653 	}
1654 fin:
1655 	if (!stayopen && st->db != NULL) {
1656 		(void)st->db->close(st->db);
1657 		st->db = NULL;
1658 	}
1659 	if (rv == NS_SUCCESS) {
1660 		if (!from_compat) {
1661 			pwd->pw_fields &= ~_PWF_SOURCE;
1662 			pwd->pw_fields |= _PWF_FILES;
1663 		}
1664 		if (retval != NULL)
1665 			*(struct passwd **)retval = pwd;
1666 	}
1667 	return (rv);
1668 }
1669 
1670 
1671 /*
1672  * common passwd line matching and parsing
1673  */
1674 int
1675 __pw_match_entry(const char *entry, size_t entrysize, enum nss_lookup_type how,
1676     const char *name, uid_t uid)
1677 {
1678 	const char	*p, *eom;
1679 	char		*q;
1680 	size_t		 len;
1681 	unsigned long	 m;
1682 
1683 	eom = entry + entrysize;
1684 	for (p = entry; p < eom; p++)
1685 		if (*p == ':')
1686 			break;
1687 	if (*p != ':')
1688 		return (NS_NOTFOUND);
1689 	if (how == nss_lt_all)
1690 		return (NS_SUCCESS);
1691 	if (how == nss_lt_name) {
1692 		len = strlen(name);
1693 		if (len == (p - entry) && memcmp(name, entry, len) == 0)
1694 			return (NS_SUCCESS);
1695 		else
1696 			return (NS_NOTFOUND);
1697 	}
1698 	for (p++; p < eom; p++)
1699 		if (*p == ':')
1700 			break;
1701 	if (*p != ':')
1702 		return (NS_NOTFOUND);
1703 	m = strtoul(++p, &q, 10);
1704 	if (q[0] != ':' || (uid_t)m != uid)
1705 		return (NS_NOTFOUND);
1706 	else
1707 		return (NS_SUCCESS);
1708 }
1709 
1710 
1711 /* XXX buffer must be NUL-terminated.  errnop is not set correctly. */
1712 int
1713 __pw_parse_entry(char *buffer, size_t bufsize __unused, struct passwd *pwd,
1714     int master, int *errnop __unused)
1715 {
1716 
1717 	if (__pw_scan(buffer, pwd, master ? _PWSCAN_MASTER : 0) == 0)
1718 		return (NS_NOTFOUND);
1719 	else
1720 		return (NS_SUCCESS);
1721 }
1722