xref: /freebsd/lib/libc/gen/getpwent.c (revision 7660b554bc59a07be0431c17e0e33815818baa69)
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 /*
938  * Test for the presence of special FreeBSD-specific master.passwd.by*
939  * maps. We do this using yp_order(). If it fails, then either the server
940  * doesn't have the map, or the YPPROC_ORDER procedure isn't supported by
941  * the server (Sun NIS+ servers in YP compat mode behave this way). If
942  * the master.passwd.by* maps don't exist, then let the lookup routine try
943  * the regular passwd.by* maps instead. If the lookup routine fails, it
944  * can return an error as needed.
945  */
946 static int
947 nis_map(char *domain, enum nss_lookup_type how, char *buffer, size_t bufsize,
948     int *master)
949 {
950 	int	rv, order;
951 
952 	*master = 0;
953 	if (geteuid() == 0) {
954 		if (snprintf(buffer, bufsize, "master.passwd.by%s",
955 		    (how == nss_lt_id) ? "uid" : "name") >= bufsize)
956 			return (NS_UNAVAIL);
957 		rv = yp_order(domain, buffer, &order);
958 		if (rv == 0) {
959 			*master = 1;
960 			return (NS_SUCCESS);
961 		}
962 	}
963 
964 	if (snprintf(buffer, bufsize, "passwd.by%s",
965 	    (how == nss_lt_id) ? "uid" : "name") >= bufsize)
966 		return (NS_UNAVAIL);
967 
968 	return (NS_SUCCESS);
969 }
970 
971 
972 static int
973 nis_adjunct(char *domain, const char *name, char *buffer, size_t bufsize)
974 {
975 	int	 rv;
976 	char	*result, *p, *q, *eor;
977 	int	 resultlen;
978 
979 	result = NULL;
980 	rv = yp_match(domain, "passwd.adjunct.byname", name, strlen(name),
981 	    &result, &resultlen);
982 	if (rv != 0)
983 		rv = 1;
984 	else {
985 		eor = &result[resultlen];
986 		p = memchr(result, ':', eor - result);
987 		if (p != NULL && ++p < eor &&
988 		    (q = memchr(p, ':', eor - p)) != NULL) {
989 			if (q - p >= bufsize)
990 				rv = -1;
991 			else {
992 				memcpy(buffer, p, q - p);
993 				buffer[q - p] ='\0';
994 			}
995 		} else
996 			rv = 1;
997 	}
998 	free(result);
999 	return (rv);
1000 }
1001 
1002 
1003 static int
1004 nis_setpwent(void *retval, void *mdata, va_list ap)
1005 {
1006 	struct nis_state	*st;
1007 	int			 rv;
1008 
1009 	rv = nis_getstate(&st);
1010 	if (rv != 0)
1011 		return (NS_UNAVAIL);
1012 	st->done = 0;
1013 	free(st->key);
1014 	st->key = NULL;
1015 	return (NS_UNAVAIL);
1016 }
1017 
1018 
1019 static int
1020 nis_passwd(void *retval, void *mdata, va_list ap)
1021 {
1022 	char		 map[YPMAXMAP];
1023 	struct nis_state *st;
1024 	struct passwd	*pwd;
1025 	const char	*name;
1026 	char		*buffer, *key, *result;
1027 	size_t		 bufsize;
1028 	uid_t		 uid;
1029 	enum nss_lookup_type how;
1030 	int		*errnop, keylen, resultlen, rv, master;
1031 
1032 	name = NULL;
1033 	uid = (uid_t)-1;
1034 	how = (enum nss_lookup_type)mdata;
1035 	switch (how) {
1036 	case nss_lt_name:
1037 		name = va_arg(ap, const char *);
1038 		break;
1039 	case nss_lt_id:
1040 		uid = va_arg(ap, uid_t);
1041 		break;
1042 	case nss_lt_all:
1043 		break;
1044 	}
1045 	pwd     = va_arg(ap, struct passwd *);
1046 	buffer  = va_arg(ap, char *);
1047 	bufsize = va_arg(ap, size_t);
1048 	errnop  = va_arg(ap, int *);
1049 	*errnop = nis_getstate(&st);
1050 	if (*errnop != 0)
1051 		return (NS_UNAVAIL);
1052 	if (st->domain[0] == '\0') {
1053 		if (getdomainname(st->domain, sizeof(st->domain)) != 0) {
1054 			*errnop = errno;
1055 			return (NS_UNAVAIL);
1056 		}
1057 	}
1058 	rv = nis_map(st->domain, how, map, sizeof(map), &master);
1059 	if (rv != NS_SUCCESS)
1060 		return (rv);
1061 	result = NULL;
1062 	do {
1063 		rv = NS_NOTFOUND;
1064 		switch (how) {
1065 		case nss_lt_name:
1066 			if (strlcpy(buffer, name, bufsize) >= bufsize)
1067 				goto erange;
1068 			break;
1069 		case nss_lt_id:
1070 			if (snprintf(buffer, bufsize, "%lu",
1071 			    (unsigned long)uid) >= bufsize)
1072 				goto erange;
1073 			break;
1074 		case nss_lt_all:
1075 			if (st->done)
1076 				goto fin;
1077 			break;
1078 		}
1079 		result = NULL;
1080 		if (how == nss_lt_all) {
1081 			if (st->key == NULL)
1082 				rv = yp_first(st->domain, map, &st->key,
1083 				    &st->keylen, &result, &resultlen);
1084 			else {
1085 				key = st->key;
1086 				keylen = st->keylen;
1087 				st->key = NULL;
1088 				rv = yp_next(st->domain, map, key, keylen,
1089 				    &st->key, &st->keylen, &result,
1090 				    &resultlen);
1091 				free(key);
1092 			}
1093 			if (rv != 0) {
1094 				free(result);
1095 				free(st->key);
1096 				st->key = NULL;
1097 				if (rv == YPERR_NOMORE)
1098 					st->done = 1;
1099 				else
1100 					rv = NS_UNAVAIL;
1101 				goto fin;
1102 			}
1103 		} else {
1104 			rv = yp_match(st->domain, map, buffer, strlen(buffer),
1105 			    &result, &resultlen);
1106 			if (rv == YPERR_KEY) {
1107 				rv = NS_NOTFOUND;
1108 				continue;
1109 			} else if (rv != 0) {
1110 				free(result);
1111 				rv = NS_UNAVAIL;
1112 				continue;
1113 			}
1114 		}
1115 		if (resultlen >= bufsize)
1116 			goto erange;
1117 		memcpy(buffer, result, resultlen);
1118 		buffer[resultlen] = '\0';
1119 		free(result);
1120 		rv = __pw_match_entry(buffer, resultlen, how, name, uid);
1121 		if (rv == NS_SUCCESS)
1122 			rv = __pw_parse_entry(buffer, resultlen, pwd, master,
1123 			    errnop);
1124 	} while (how == nss_lt_all && !(rv & NS_TERMINATE));
1125 fin:
1126 	if (rv == NS_SUCCESS) {
1127 		if (strstr(pwd->pw_passwd, "##") != NULL) {
1128 			rv = nis_adjunct(st->domain, name,
1129 			    &buffer[resultlen+1], bufsize-resultlen-1);
1130 			if (rv < 0)
1131 				goto erange;
1132 			else if (rv == 0)
1133 				pwd->pw_passwd = &buffer[resultlen+1];
1134 		}
1135 		pwd->pw_fields &= ~_PWF_SOURCE;
1136 		pwd->pw_fields |= _PWF_NIS;
1137 		if (retval != NULL)
1138 			*(struct passwd **)retval = pwd;
1139 	}
1140 	return (rv);
1141 erange:
1142 	*errnop = ERANGE;
1143 	return (NS_RETURN);
1144 }
1145 #endif /* YP */
1146 
1147 
1148 /*
1149  * compat backend
1150  */
1151 static void
1152 compat_clear_template(struct passwd *template)
1153 {
1154 
1155 	free(template->pw_passwd);
1156 	free(template->pw_gecos);
1157 	free(template->pw_dir);
1158 	free(template->pw_shell);
1159 	memset(template, 0, sizeof(*template));
1160 }
1161 
1162 
1163 static int
1164 compat_set_template(struct passwd *src, struct passwd *template)
1165 {
1166 
1167 	compat_clear_template(template);
1168 #ifdef PW_OVERRIDE_PASSWD
1169 	if ((src->pw_fields & _PWF_PASSWD) &&
1170 	    (template->pw_passwd = strdup(src->pw_passwd)) == NULL)
1171 		goto enomem;
1172 #endif
1173 	if (src->pw_fields & _PWF_UID)
1174 		template->pw_uid = src->pw_uid;
1175 	if (src->pw_fields & _PWF_GID)
1176 		template->pw_gid = src->pw_gid;
1177 	if ((src->pw_fields & _PWF_GECOS) &&
1178 	    (template->pw_gecos = strdup(src->pw_gecos)) == NULL)
1179 		goto enomem;
1180 	if ((src->pw_fields & _PWF_DIR) &&
1181 	    (template->pw_dir = strdup(src->pw_dir)) == NULL)
1182 		goto enomem;
1183 	if ((src->pw_fields & _PWF_SHELL) &&
1184 	    (template->pw_shell = strdup(src->pw_shell)) == NULL)
1185 		goto enomem;
1186 	template->pw_fields = src->pw_fields;
1187 	return (0);
1188 enomem:
1189 	syslog(LOG_ERR, "getpwent memory allocation failure");
1190 	return (-1);
1191 }
1192 
1193 
1194 static int
1195 compat_use_template(struct passwd *pwd, struct passwd *template, char *buffer,
1196     size_t bufsize)
1197 {
1198 	struct passwd hold;
1199 	char	*copy, *p, *q, *eob;
1200 	size_t	 n;
1201 
1202 	/* We cannot know the layout of the password fields in `buffer',
1203 	 * so we have to copy everything.
1204 	 */
1205 	if (template->pw_fields == 0) /* nothing to fill-in */
1206 		return (0);
1207 	n = 0;
1208 	n += pwd->pw_name != NULL ? strlen(pwd->pw_name) + 1 : 0;
1209 	n += pwd->pw_passwd != NULL ? strlen(pwd->pw_passwd) + 1 : 0;
1210 	n += pwd->pw_class != NULL ? strlen(pwd->pw_class) + 1 : 0;
1211 	n += pwd->pw_gecos != NULL ? strlen(pwd->pw_gecos) + 1 : 0;
1212 	n += pwd->pw_dir != NULL ? strlen(pwd->pw_dir) + 1 : 0;
1213 	n += pwd->pw_shell != NULL ? strlen(pwd->pw_shell) + 1 : 0;
1214 	copy = malloc(n);
1215 	if (copy == NULL) {
1216 		syslog(LOG_ERR, "getpwent memory allocation failure");
1217 		return (ENOMEM);
1218 	}
1219 	p = copy;
1220 	eob = &copy[n];
1221 #define COPY(field) do {				\
1222 	if (pwd->field == NULL)				\
1223 		hold.field = NULL;			\
1224 	else {						\
1225 		hold.field = p;				\
1226 		p += strlcpy(p, pwd->field, eob-p) + 1;	\
1227 	}						\
1228 } while (0)
1229 	COPY(pw_name);
1230 	COPY(pw_passwd);
1231 	COPY(pw_class);
1232 	COPY(pw_gecos);
1233 	COPY(pw_dir);
1234 	COPY(pw_shell);
1235 #undef COPY
1236 	p = buffer;
1237 	eob = &buffer[bufsize];
1238 #define COPY(field, flag) do {						 \
1239 	q = (template->pw_fields & flag) ? template->field : hold.field; \
1240 	if (q == NULL)							 \
1241 		pwd->field = NULL;					 \
1242 	else {								 \
1243 		pwd->field = p;						 \
1244 		if ((n = strlcpy(p, q, eob-p)) >= eob-p) {		 \
1245 			free(copy);					 \
1246 			return (ERANGE);				 \
1247 		}							 \
1248 		p += n + 1;						 \
1249 	}								 \
1250 } while (0)
1251 	COPY(pw_name, 0);
1252 #ifdef PW_OVERRIDE_PASSWD
1253 	COPY(pw_passwd, _PWF_PASSWD);
1254 #else
1255 	COPY(pw_passwd, 0);
1256 #endif
1257 	COPY(pw_class, 0);
1258 	COPY(pw_gecos, _PWF_GECOS);
1259 	COPY(pw_dir, _PWF_DIR);
1260 	COPY(pw_shell, _PWF_SHELL);
1261 #undef COPY
1262 #define COPY(field, flag) do {			\
1263 	if (template->pw_fields & flag)		\
1264 		pwd->field = template->field;	\
1265 } while (0)
1266 	COPY(pw_uid, _PWF_UID);
1267 	COPY(pw_gid, _PWF_GID);
1268 #undef COPY
1269 	free(copy);
1270 	return (0);
1271 }
1272 
1273 
1274 static int
1275 compat_exclude(const char *name, DB **db)
1276 {
1277 	DBT	key, data;
1278 
1279 	if (*db == NULL &&
1280 	    (*db = dbopen(NULL, O_RDWR, 600, DB_HASH, 0)) == NULL)
1281 		return (errno);
1282 	key.size = strlen(name);
1283 	key.data = (char *)name;
1284 	data.size = 0;
1285 	data.data = NULL;
1286 
1287 	if ((*db)->put(*db, &key, &data, 0) == -1)
1288 		return (errno);
1289 	return (0);
1290 }
1291 
1292 
1293 static int
1294 compat_is_excluded(const char *name, DB *db)
1295 {
1296 	DBT	key, data;
1297 
1298 	if (db == NULL)
1299 		return (0);
1300 	key.size = strlen(name);
1301 	key.data = (char *)name;
1302 	return (db->get(db, &key, &data, 0) == 0);
1303 }
1304 
1305 
1306 static int
1307 compat_redispatch(struct compat_state *st, enum nss_lookup_type how,
1308     enum nss_lookup_type lookup_how, const char *name, const char *lookup_name,
1309     uid_t uid, struct passwd *pwd, char *buffer, size_t bufsize, int *errnop)
1310 {
1311 	static const ns_src compatsrc[] = {
1312 #ifdef YP
1313 		{ NSSRC_NIS, NS_SUCCESS },
1314 #endif
1315 		{ NULL, 0 }
1316 	};
1317 	ns_dtab dtab[] = {
1318 #ifdef YP
1319 		{ NSSRC_NIS, nis_passwd, NULL },
1320 #endif
1321 #ifdef HESIOD
1322 		{ NSSRC_DNS, dns_passwd, NULL },
1323 #endif
1324 		{ NULL, NULL, NULL }
1325 	};
1326 	void		*discard;
1327 	int		 rv, e, i;
1328 
1329 	for (i = 0; i < sizeof(dtab)/sizeof(dtab[0]) - 1; i++)
1330 		dtab[i].mdata = (void *)lookup_how;
1331 more:
1332 	pwd_init(pwd);
1333 	switch (lookup_how) {
1334 	case nss_lt_all:
1335 		rv = _nsdispatch(&discard, dtab, NSDB_PASSWD_COMPAT,
1336 		    "getpwent_r", compatsrc, pwd, buffer, bufsize,
1337 		    errnop);
1338 		break;
1339 	case nss_lt_id:
1340 		rv = _nsdispatch(&discard, dtab, NSDB_PASSWD_COMPAT,
1341 		    "getpwuid_r", compatsrc, uid, pwd, buffer,
1342 		    bufsize, errnop);
1343 		break;
1344 	case nss_lt_name:
1345 		rv = _nsdispatch(&discard, dtab, NSDB_PASSWD_COMPAT,
1346 		    "getpwnam_r", compatsrc, lookup_name, pwd, buffer,
1347 		    bufsize, errnop);
1348 		break;
1349 	default:
1350 		return (NS_UNAVAIL);
1351 	}
1352 	if (rv != NS_SUCCESS)
1353 		return (rv);
1354 	if (compat_is_excluded(pwd->pw_name, st->exclude)) {
1355 		if (how == nss_lt_all)
1356 			goto more;
1357 		return (NS_NOTFOUND);
1358 	}
1359 	e = compat_use_template(pwd, &st->template, buffer, bufsize);
1360 	if (e != 0) {
1361 		*errnop = e;
1362 		if (e == ERANGE)
1363 			return (NS_RETURN);
1364 		else
1365 			return (NS_UNAVAIL);
1366 	}
1367 	switch (how) {
1368 	case nss_lt_name:
1369 		if (strcmp(name, pwd->pw_name) != 0)
1370 			return (NS_NOTFOUND);
1371 		break;
1372 	case nss_lt_id:
1373 		if (uid != pwd->pw_uid)
1374 			return (NS_NOTFOUND);
1375 		break;
1376 	default:
1377 		break;
1378 	}
1379 	return (NS_SUCCESS);
1380 }
1381 
1382 
1383 static void
1384 compat_endstate(void *p)
1385 {
1386 	struct compat_state *st;
1387 
1388 	if (p == NULL)
1389 		return;
1390 	st = (struct compat_state *)p;
1391 	if (st->db != NULL)
1392 		st->db->close(st->db);
1393 	if (st->exclude != NULL)
1394 		st->exclude->close(st->exclude);
1395 	compat_clear_template(&st->template);
1396 	free(p);
1397 }
1398 
1399 
1400 static int
1401 compat_setpwent(void *retval, void *mdata, va_list ap)
1402 {
1403 	static const ns_src compatsrc[] = {
1404 #ifdef YP
1405 		{ NSSRC_NIS, NS_SUCCESS },
1406 #endif
1407 		{ NULL, 0 }
1408 	};
1409 	ns_dtab dtab[] = {
1410 #ifdef YP
1411 		{ NSSRC_NIS, nis_setpwent, NULL },
1412 #endif
1413 #ifdef HESIOD
1414 		{ NSSRC_DNS, dns_setpwent, NULL },
1415 #endif
1416 		{ NULL, NULL, NULL }
1417 	};
1418 	struct compat_state	*st;
1419 	int			 rv, stayopen;
1420 
1421 #define set_setent(x, y) do {	 				\
1422 	int i;							\
1423 								\
1424 	for (i = 0; i < (sizeof(x)/sizeof(x[0])) - 1; i++)	\
1425 		x[i].mdata = (void *)y;				\
1426 } while (0)
1427 
1428 	rv = compat_getstate(&st);
1429 	if (rv != 0)
1430 		return (NS_UNAVAIL);
1431 	switch ((enum constants)mdata) {
1432 	case SETPWENT:
1433 		stayopen = va_arg(ap, int);
1434 		st->keynum = 0;
1435 		if (stayopen)
1436 			st->db = pwdbopen(&st->version);
1437 		st->stayopen = stayopen;
1438 		set_setent(dtab, mdata);
1439 		(void)_nsdispatch(NULL, dtab, NSDB_PASSWD_COMPAT, "setpwent",
1440 		    compatsrc, 0);
1441 		break;
1442 	case ENDPWENT:
1443 		if (st->db != NULL) {
1444 			(void)st->db->close(st->db);
1445 			st->db = NULL;
1446 		}
1447 		set_setent(dtab, mdata);
1448 		(void)_nsdispatch(NULL, dtab, NSDB_PASSWD_COMPAT, "endpwent",
1449 		    compatsrc, 0);
1450 		break;
1451 	default:
1452 		break;
1453 	}
1454 	return (NS_UNAVAIL);
1455 #undef set_setent
1456 }
1457 
1458 
1459 static int
1460 compat_passwd(void *retval, void *mdata, va_list ap)
1461 {
1462 	char			 keybuf[MAXLOGNAME + 1];
1463 	DBT			 key, entry;
1464 	struct compat_state	*st;
1465 	enum nss_lookup_type	 how;
1466 	const char		*name;
1467 	struct passwd		*pwd;
1468 	char			*buffer, *pw_name;
1469 	char			*host, *user, *domain;
1470 	size_t			 bufsize;
1471 	uid_t			 uid;
1472 	uint32_t		 store;
1473 	int			 rv, from_compat, stayopen, *errnop;
1474 
1475 	from_compat = 0;
1476 	name = NULL;
1477 	uid = (uid_t)-1;
1478 	how = (enum nss_lookup_type)mdata;
1479 	switch (how) {
1480 	case nss_lt_name:
1481 		name = va_arg(ap, const char *);
1482 		break;
1483 	case nss_lt_id:
1484 		uid = va_arg(ap, uid_t);
1485 		break;
1486 	case nss_lt_all:
1487 		break;
1488 	default:
1489 		rv = NS_NOTFOUND;
1490 		goto fin;
1491 	}
1492 	pwd = va_arg(ap, struct passwd *);
1493 	buffer = va_arg(ap, char *);
1494 	bufsize = va_arg(ap, size_t);
1495 	errnop = va_arg(ap, int *);
1496 	*errnop = compat_getstate(&st);
1497 	if (*errnop != 0)
1498 		return (NS_UNAVAIL);
1499 	if (how == nss_lt_all && st->keynum < 0) {
1500 		rv = NS_NOTFOUND;
1501 		goto fin;
1502 	}
1503 	if (st->db == NULL &&
1504 	    (st->db = pwdbopen(&st->version)) == NULL) {
1505 		*errnop = errno;
1506 		rv = NS_UNAVAIL;
1507 		goto fin;
1508 	}
1509 	if (how == nss_lt_all) {
1510 		if (st->keynum < 0) {
1511 			rv = NS_NOTFOUND;
1512 			goto fin;
1513 		}
1514 		stayopen = 1;
1515 	} else {
1516 		st->keynum = 0;
1517 		stayopen = st->stayopen;
1518 	}
1519 docompat:
1520 	rv = NS_NOTFOUND;
1521 	switch (st->compat) {
1522 	case COMPAT_MODE_ALL:
1523 		rv = compat_redispatch(st, how, how, name, name, uid, pwd,
1524 		    buffer, bufsize, errnop);
1525 		if (rv != NS_SUCCESS)
1526 			st->compat = COMPAT_MODE_OFF;
1527 		break;
1528 	case COMPAT_MODE_NETGROUP:
1529 		/* XXX getnetgrent is not thread-safe. */
1530 		do {
1531 			rv = getnetgrent(&host, &user, &domain);
1532 			if (rv == 0) {
1533 				endnetgrent();
1534 				st->compat = COMPAT_MODE_OFF;
1535 				rv = NS_NOTFOUND;
1536 				continue;
1537 			} else if (user == NULL || user[0] == '\0')
1538 				continue;
1539 			rv = compat_redispatch(st, how, nss_lt_name, name,
1540 			    user, uid, pwd, buffer, bufsize, errnop);
1541 		} while (st->compat == COMPAT_MODE_NETGROUP &&
1542 		    !(rv & NS_TERMINATE));
1543 		break;
1544 	case COMPAT_MODE_NAME:
1545 		rv = compat_redispatch(st, how, nss_lt_name, name, st->name,
1546 		    uid, pwd, buffer, bufsize, errnop);
1547 		free(st->name);
1548 		st->name = NULL;
1549 		st->compat = COMPAT_MODE_OFF;
1550 		break;
1551 	default:
1552 		break;
1553 	}
1554 	if (rv & NS_TERMINATE) {
1555 		from_compat = 1;
1556 		goto fin;
1557 	}
1558 	key.data = keybuf;
1559 	rv = NS_NOTFOUND;
1560 	while (st->keynum >= 0) {
1561 		st->keynum++;
1562 		if (st->version < _PWD_CURRENT_VERSION) {
1563 			memcpy(&keybuf[1], &st->keynum, sizeof(st->keynum));
1564 			key.size = sizeof(st->keynum) + 1;
1565 		} else {
1566 			store = htonl(st->keynum);
1567 			memcpy(&keybuf[1], &store, sizeof(store));
1568 			key.size = sizeof(store) + 1;
1569 		}
1570 		keybuf[0] = _PW_VERSIONED(_PW_KEYBYNUM, st->version);
1571 		rv = st->db->get(st->db, &key, &entry, 0);
1572 		if (rv < 0 || rv > 1) { /* should never return > 1 */
1573 			*errnop = errno;
1574 			rv = NS_UNAVAIL;
1575 			goto fin;
1576 		} else if (rv == 1) {
1577 			st->keynum = -1;
1578 			rv = NS_NOTFOUND;
1579 			goto fin;
1580 		}
1581 		pw_name = (char *)entry.data;
1582 		switch (pw_name[0]) {
1583 		case '+':
1584 			switch (pw_name[1]) {
1585 			case '\0':
1586 				st->compat = COMPAT_MODE_ALL;
1587 				break;
1588 			case '@':
1589 				setnetgrent(&pw_name[2]);
1590 				st->compat = COMPAT_MODE_NETGROUP;
1591 				break;
1592 			default:
1593 				st->name = strdup(&pw_name[1]);
1594 				if (st->name == NULL) {
1595 					syslog(LOG_ERR,
1596 					 "getpwent memory allocation failure");
1597 					*errnop = ENOMEM;
1598 					rv = NS_UNAVAIL;
1599 					break;
1600 				}
1601 				st->compat = COMPAT_MODE_NAME;
1602 			}
1603 			if (entry.size > bufsize) {
1604 				*errnop = ERANGE;
1605 				rv = NS_RETURN;
1606 				goto fin;
1607 			}
1608 			memcpy(buffer, entry.data, entry.size);
1609 			rv = pwdb_versions[st->version].parse(buffer,
1610 			    entry.size, pwd, errnop);
1611 			if (rv != NS_SUCCESS)
1612 				;
1613 			else if (compat_set_template(pwd, &st->template) < 0) {
1614 				*errnop = ENOMEM;
1615 				rv = NS_UNAVAIL;
1616 				goto fin;
1617 			}
1618 			goto docompat;
1619 		case '-':
1620 			switch (pw_name[1]) {
1621 			case '\0':
1622 				/* XXX Maybe syslog warning */
1623 				continue;
1624 			case '@':
1625 				setnetgrent(&pw_name[2]);
1626 				while (getnetgrent(&host, &user, &domain) !=
1627 				    NULL) {
1628 					if (user != NULL && user[0] != '\0')
1629 						compat_exclude(user,
1630 						    &st->exclude);
1631 				}
1632 				endnetgrent();
1633 				continue;
1634 			default:
1635 				compat_exclude(&pw_name[1], &st->exclude);
1636 				continue;
1637 			}
1638 			break;
1639 		default:
1640 			break;
1641 		}
1642 		if (compat_is_excluded((char *)entry.data, st->exclude))
1643 			continue;
1644 		rv = pwdb_versions[st->version].match(entry.data, entry.size,
1645 		    how, name, uid);
1646 		if (rv == NS_RETURN)
1647 			break;
1648 		else if (rv != NS_SUCCESS)
1649 			continue;
1650 		if (entry.size > bufsize) {
1651 			*errnop = ERANGE;
1652 			rv = NS_RETURN;
1653 			break;
1654 		}
1655 		memcpy(buffer, entry.data, entry.size);
1656 		rv = pwdb_versions[st->version].parse(buffer, entry.size, pwd,
1657 		    errnop);
1658 		if (rv & NS_TERMINATE)
1659 			break;
1660 	}
1661 fin:
1662 	if (!stayopen && st->db != NULL) {
1663 		(void)st->db->close(st->db);
1664 		st->db = NULL;
1665 	}
1666 	if (rv == NS_SUCCESS) {
1667 		if (!from_compat) {
1668 			pwd->pw_fields &= ~_PWF_SOURCE;
1669 			pwd->pw_fields |= _PWF_FILES;
1670 		}
1671 		if (retval != NULL)
1672 			*(struct passwd **)retval = pwd;
1673 	}
1674 	return (rv);
1675 }
1676 
1677 
1678 /*
1679  * common passwd line matching and parsing
1680  */
1681 int
1682 __pw_match_entry(const char *entry, size_t entrysize, enum nss_lookup_type how,
1683     const char *name, uid_t uid)
1684 {
1685 	const char	*p, *eom;
1686 	char		*q;
1687 	size_t		 len;
1688 	unsigned long	 m;
1689 
1690 	eom = entry + entrysize;
1691 	for (p = entry; p < eom; p++)
1692 		if (*p == ':')
1693 			break;
1694 	if (*p != ':')
1695 		return (NS_NOTFOUND);
1696 	if (how == nss_lt_all)
1697 		return (NS_SUCCESS);
1698 	if (how == nss_lt_name) {
1699 		len = strlen(name);
1700 		if (len == (p - entry) && memcmp(name, entry, len) == 0)
1701 			return (NS_SUCCESS);
1702 		else
1703 			return (NS_NOTFOUND);
1704 	}
1705 	for (p++; p < eom; p++)
1706 		if (*p == ':')
1707 			break;
1708 	if (*p != ':')
1709 		return (NS_NOTFOUND);
1710 	m = strtoul(++p, &q, 10);
1711 	if (q[0] != ':' || (uid_t)m != uid)
1712 		return (NS_NOTFOUND);
1713 	else
1714 		return (NS_SUCCESS);
1715 }
1716 
1717 
1718 /* XXX buffer must be NUL-terminated.  errnop is not set correctly. */
1719 int
1720 __pw_parse_entry(char *buffer, size_t bufsize __unused, struct passwd *pwd,
1721     int master, int *errnop __unused)
1722 {
1723 
1724 	if (__pw_scan(buffer, pwd, master ? _PWSCAN_MASTER : 0) == 0)
1725 		return (NS_NOTFOUND);
1726 	else
1727 		return (NS_SUCCESS);
1728 }
1729