xref: /freebsd/lib/libc/gen/getpwent.c (revision 0957b409a90fd597c1e9124cbaf3edd2b488f4ac)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2003 Networks Associates Technology, Inc.
5  * All rights reserved.
6  *
7  * This software was developed for the FreeBSD Project by
8  * Jacques A. Vidrine, Safeport Network Services, and Network
9  * Associates Laboratories, the Security Research Division of Network
10  * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035
11  * ("CBOSS"), as part of the DARPA CHATS research program.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  */
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 #include "namespace.h"
39 #include <sys/param.h>
40 #ifdef YP
41 #include <rpc/rpc.h>
42 #include <rpcsvc/yp_prot.h>
43 #include <rpcsvc/ypclnt.h>
44 #endif
45 #include <arpa/inet.h>
46 #include <errno.h>
47 #include <fcntl.h>
48 #ifdef HESIOD
49 #include <hesiod.h>
50 #endif
51 #include <netdb.h>
52 #include <nsswitch.h>
53 #include <pthread.h>
54 #include <pthread_np.h>
55 #include <pwd.h>
56 #include <stdlib.h>
57 #include <stdio.h>
58 #include <string.h>
59 #include <syslog.h>
60 #include <unistd.h>
61 #include "un-namespace.h"
62 #include <db.h>
63 #include "libc_private.h"
64 #include "pw_scan.h"
65 #include "nss_tls.h"
66 #ifdef NS_CACHING
67 #include "nscache.h"
68 #endif
69 
70 #ifndef CTASSERT
71 #define CTASSERT(x)		_CTASSERT(x, __LINE__)
72 #define _CTASSERT(x, y)		__CTASSERT(x, y)
73 #define __CTASSERT(x, y)	typedef char __assert_ ## y [(x) ? 1 : -1]
74 #endif
75 
76 /* Counter as stored in /etc/pwd.db */
77 typedef	int		pwkeynum;
78 
79 CTASSERT(MAXLOGNAME > sizeof(uid_t));
80 CTASSERT(MAXLOGNAME > sizeof(pwkeynum));
81 
82 enum constants {
83 	PWD_STORAGE_INITIAL	= 1 << 10, /* 1 KByte */
84 	PWD_STORAGE_MAX		= 1 << 20, /* 1 MByte */
85 	SETPWENT		= 1,
86 	ENDPWENT		= 2,
87 	HESIOD_NAME_MAX		= 256
88 };
89 
90 static const ns_src defaultsrc[] = {
91 	{ NSSRC_COMPAT, NS_SUCCESS },
92 	{ NULL, 0 }
93 };
94 
95 int	__pw_match_entry(const char *, size_t, enum nss_lookup_type,
96 	    const char *, uid_t);
97 int	__pw_parse_entry(char *, size_t, struct passwd *, int, int *errnop);
98 
99 union key {
100 	const char	*name;
101 	uid_t		 uid;
102 };
103 
104 static	struct passwd *getpw(int (*fn)(union key, struct passwd *, char *,
105 		    size_t, struct passwd **), union key);
106 static	int	 wrap_getpwnam_r(union key, struct passwd *, char *,
107 		    size_t, struct passwd **);
108 static	int	 wrap_getpwuid_r(union key, struct passwd *, char *, size_t,
109 		    struct passwd **);
110 static	int	 wrap_getpwent_r(union key, struct passwd *, char *, size_t,
111 		    struct passwd **);
112 
113 static	int	 pwdb_match_entry_v3(char *, size_t, enum nss_lookup_type,
114 		    const char *, uid_t);
115 static	int	 pwdb_parse_entry_v3(char *, size_t, struct passwd *, int *);
116 static	int	 pwdb_match_entry_v4(char *, size_t, enum nss_lookup_type,
117 		    const char *, uid_t);
118 static	int	 pwdb_parse_entry_v4(char *, size_t, struct passwd *, int *);
119 
120 
121 struct {
122 	int	(*match)(char *, size_t, enum nss_lookup_type, const char *,
123 		    uid_t);
124 	int	(*parse)(char *, size_t, struct passwd *, int *);
125 } pwdb_versions[] = {
126 	{ NULL, NULL },					/* version 0 */
127 	{ NULL, NULL },					/* version 1 */
128 	{ NULL, NULL },					/* version 2 */
129 	{ pwdb_match_entry_v3, pwdb_parse_entry_v3 },	/* version 3 */
130 	{ pwdb_match_entry_v4, pwdb_parse_entry_v4 },	/* version 4 */
131 };
132 
133 
134 struct files_state {
135 	DB		*db;
136 	pwkeynum	 keynum;
137 	int		 stayopen;
138 	int		 version;
139 };
140 static	void	files_endstate(void *);
141 NSS_TLS_HANDLING(files);
142 static	DB	*pwdbopen(int *);
143 static	void	 files_endstate(void *);
144 static	int	 files_setpwent(void *, void *, va_list);
145 static	int	 files_passwd(void *, void *, va_list);
146 
147 
148 #ifdef HESIOD
149 struct dns_state {
150 	long	counter;
151 };
152 static	void	dns_endstate(void *);
153 NSS_TLS_HANDLING(dns);
154 static	int	 dns_setpwent(void *, void *, va_list);
155 static	int	 dns_passwd(void *, void *, va_list);
156 #endif
157 
158 
159 #ifdef YP
160 struct nis_state {
161 	char	 domain[MAXHOSTNAMELEN];
162 	int	 done;
163 	char	*key;
164 	int	 keylen;
165 };
166 static	void	 nis_endstate(void *);
167 NSS_TLS_HANDLING(nis);
168 static	int	 nis_setpwent(void *, void *, va_list);
169 static	int	 nis_passwd(void *, void *, va_list);
170 static	int	 nis_map(char *, enum nss_lookup_type, char *, size_t, int *);
171 static	int	 nis_adjunct(char *, const char *, char *, size_t);
172 #endif
173 
174 
175 struct compat_state {
176 	DB		*db;
177 	pwkeynum	 keynum;
178 	int		 stayopen;
179 	int		 version;
180 	DB		*exclude;
181 	struct passwd	 template;
182 	char		*name;
183 	enum _compat {
184 		COMPAT_MODE_OFF = 0,
185 		COMPAT_MODE_ALL,
186 		COMPAT_MODE_NAME,
187 		COMPAT_MODE_NETGROUP
188 	}		 compat;
189 };
190 static	void	 compat_endstate(void *);
191 NSS_TLS_HANDLING(compat);
192 static	int	 compat_setpwent(void *, void *, va_list);
193 static	int	 compat_passwd(void *, void *, va_list);
194 static	void	 compat_clear_template(struct passwd *);
195 static	int	 compat_set_template(struct passwd *, struct passwd *);
196 static	int	 compat_use_template(struct passwd *, struct passwd *, char *,
197 		    size_t);
198 static	int	 compat_redispatch(struct compat_state *, enum nss_lookup_type,
199 		    enum nss_lookup_type, const char *, const char *, uid_t,
200 		    struct passwd *, char *, size_t, int *);
201 
202 #ifdef NS_CACHING
203 static	int	 pwd_id_func(char *, size_t *, va_list ap, void *);
204 static	int	 pwd_marshal_func(char *, size_t *, void *, va_list, void *);
205 static	int	 pwd_unmarshal_func(char *, size_t, void *, va_list, void *);
206 
207 static int
208 pwd_id_func(char *buffer, size_t *buffer_size, va_list ap, void *cache_mdata)
209 {
210 	char	*name;
211 	uid_t	uid;
212 	size_t	size, desired_size;
213 	int	res = NS_UNAVAIL;
214 	enum nss_lookup_type lookup_type;
215 
216 	lookup_type = (enum nss_lookup_type)cache_mdata;
217 	switch (lookup_type) {
218 	case nss_lt_name:
219 		name = va_arg(ap, char *);
220 		size = strlen(name);
221 		desired_size = sizeof(enum nss_lookup_type) + size + 1;
222 		if (desired_size > *buffer_size) {
223 			res = NS_RETURN;
224 			goto fin;
225 		}
226 
227 		memcpy(buffer, &lookup_type, sizeof(enum nss_lookup_type));
228 		memcpy(buffer + sizeof(enum nss_lookup_type), name, size + 1);
229 
230 		res = NS_SUCCESS;
231 		break;
232 	case nss_lt_id:
233 		uid = va_arg(ap, uid_t);
234 		desired_size = sizeof(enum nss_lookup_type) + sizeof(uid_t);
235 		if (desired_size > *buffer_size) {
236 			res = NS_RETURN;
237 			goto fin;
238 		}
239 
240 		memcpy(buffer, &lookup_type, sizeof(enum nss_lookup_type));
241 		memcpy(buffer + sizeof(enum nss_lookup_type), &uid,
242 		    sizeof(uid_t));
243 
244 		res = NS_SUCCESS;
245 		break;
246 	default:
247 		/* should be unreachable */
248 		return (NS_UNAVAIL);
249 	}
250 
251 fin:
252 	*buffer_size = desired_size;
253 	return (res);
254 }
255 
256 static int
257 pwd_marshal_func(char *buffer, size_t *buffer_size, void *retval, va_list ap,
258     void *cache_mdata)
259 {
260 	char *name;
261 	uid_t uid;
262 	struct passwd *pwd;
263 	char *orig_buf;
264 	size_t orig_buf_size;
265 
266 	struct passwd new_pwd;
267 	size_t desired_size, size;
268 	char *p;
269 
270 	switch ((enum nss_lookup_type)cache_mdata) {
271 	case nss_lt_name:
272 		name = va_arg(ap, char *);
273 		break;
274 	case nss_lt_id:
275 		uid = va_arg(ap, uid_t);
276 		break;
277 	case nss_lt_all:
278 		break;
279 	default:
280 		/* should be unreachable */
281 		return (NS_UNAVAIL);
282 	}
283 
284 	pwd = va_arg(ap, struct passwd *);
285 	orig_buf = va_arg(ap, char *);
286 	orig_buf_size = va_arg(ap, size_t);
287 
288 	desired_size = sizeof(struct passwd) + sizeof(char *) +
289 	    strlen(pwd->pw_name) + 1;
290 	if (pwd->pw_passwd != NULL)
291 		desired_size += strlen(pwd->pw_passwd) + 1;
292 	if (pwd->pw_class != NULL)
293 		desired_size += strlen(pwd->pw_class) + 1;
294 	if (pwd->pw_gecos != NULL)
295 		desired_size += strlen(pwd->pw_gecos) + 1;
296 	if (pwd->pw_dir != NULL)
297 		desired_size += strlen(pwd->pw_dir) + 1;
298 	if (pwd->pw_shell != NULL)
299 		desired_size += strlen(pwd->pw_shell) + 1;
300 
301 	if (*buffer_size < desired_size) {
302 		/* this assignment is here for future use */
303 		*buffer_size = desired_size;
304 		return (NS_RETURN);
305 	}
306 
307 	memcpy(&new_pwd, pwd, sizeof(struct passwd));
308 	memset(buffer, 0, desired_size);
309 
310 	*buffer_size = desired_size;
311 	p = buffer + sizeof(struct passwd) + sizeof(char *);
312 	memcpy(buffer + sizeof(struct passwd), &p, sizeof(char *));
313 
314 	if (new_pwd.pw_name != NULL) {
315 		size = strlen(new_pwd.pw_name);
316 		memcpy(p, new_pwd.pw_name, size);
317 		new_pwd.pw_name = p;
318 		p += size + 1;
319 	}
320 
321 	if (new_pwd.pw_passwd != NULL) {
322 		size = strlen(new_pwd.pw_passwd);
323 		memcpy(p, new_pwd.pw_passwd, size);
324 		new_pwd.pw_passwd = p;
325 		p += size + 1;
326 	}
327 
328 	if (new_pwd.pw_class != NULL) {
329 		size = strlen(new_pwd.pw_class);
330 		memcpy(p, new_pwd.pw_class, size);
331 		new_pwd.pw_class = p;
332 		p += size + 1;
333 	}
334 
335 	if (new_pwd.pw_gecos != NULL) {
336 		size = strlen(new_pwd.pw_gecos);
337 		memcpy(p, new_pwd.pw_gecos, size);
338 		new_pwd.pw_gecos = p;
339 		p += size + 1;
340 	}
341 
342 	if (new_pwd.pw_dir != NULL) {
343 		size = strlen(new_pwd.pw_dir);
344 		memcpy(p, new_pwd.pw_dir, size);
345 		new_pwd.pw_dir = p;
346 		p += size + 1;
347 	}
348 
349 	if (new_pwd.pw_shell != NULL) {
350 		size = strlen(new_pwd.pw_shell);
351 		memcpy(p, new_pwd.pw_shell, size);
352 		new_pwd.pw_shell = p;
353 		p += size + 1;
354 	}
355 
356 	memcpy(buffer, &new_pwd, sizeof(struct passwd));
357 	return (NS_SUCCESS);
358 }
359 
360 static int
361 pwd_unmarshal_func(char *buffer, size_t buffer_size, void *retval, va_list ap,
362     void *cache_mdata)
363 {
364 	char *name;
365 	uid_t uid;
366 	struct passwd *pwd;
367 	char *orig_buf;
368 	size_t orig_buf_size;
369 	int *ret_errno;
370 
371 	char *p;
372 
373 	switch ((enum nss_lookup_type)cache_mdata) {
374 	case nss_lt_name:
375 		name = va_arg(ap, char *);
376 		break;
377 	case nss_lt_id:
378 		uid = va_arg(ap, uid_t);
379 		break;
380 	case nss_lt_all:
381 		break;
382 	default:
383 		/* should be unreachable */
384 		return (NS_UNAVAIL);
385 	}
386 
387 	pwd = va_arg(ap, struct passwd *);
388 	orig_buf = va_arg(ap, char *);
389 	orig_buf_size = va_arg(ap, size_t);
390 	ret_errno = va_arg(ap, int *);
391 
392 	if (orig_buf_size <
393 	    buffer_size - sizeof(struct passwd) - sizeof(char *)) {
394 		*ret_errno = ERANGE;
395 		return (NS_RETURN);
396 	}
397 
398 	memcpy(pwd, buffer, sizeof(struct passwd));
399 	memcpy(&p, buffer + sizeof(struct passwd), sizeof(char *));
400 	memcpy(orig_buf, buffer + sizeof(struct passwd) + sizeof(char *),
401 	    buffer_size - sizeof(struct passwd) - sizeof(char *));
402 
403 	NS_APPLY_OFFSET(pwd->pw_name, orig_buf, p, char *);
404 	NS_APPLY_OFFSET(pwd->pw_passwd, orig_buf, p, char *);
405 	NS_APPLY_OFFSET(pwd->pw_class, orig_buf, p, char *);
406 	NS_APPLY_OFFSET(pwd->pw_gecos, orig_buf, p, char *);
407 	NS_APPLY_OFFSET(pwd->pw_dir, orig_buf, p, char *);
408 	NS_APPLY_OFFSET(pwd->pw_shell, orig_buf, p, char *);
409 
410 	if (retval != NULL)
411 		*((struct passwd **)retval) = pwd;
412 
413 	return (NS_SUCCESS);
414 }
415 
416 NSS_MP_CACHE_HANDLING(passwd);
417 #endif /* NS_CACHING */
418 
419 void
420 setpwent(void)
421 {
422 #ifdef NS_CACHING
423 	static const nss_cache_info cache_info = NS_MP_CACHE_INFO_INITIALIZER(
424 		passwd, (void *)nss_lt_all,
425 		NULL, NULL);
426 #endif
427 
428 	static const ns_dtab dtab[] = {
429 		{ NSSRC_FILES, files_setpwent, (void *)SETPWENT },
430 #ifdef HESIOD
431 		{ NSSRC_DNS, dns_setpwent, (void *)SETPWENT },
432 #endif
433 #ifdef YP
434 		{ NSSRC_NIS, nis_setpwent, (void *)SETPWENT },
435 #endif
436 		{ NSSRC_COMPAT, compat_setpwent, (void *)SETPWENT },
437 #ifdef NS_CACHING
438 		NS_CACHE_CB(&cache_info)
439 #endif
440 		{ NULL, NULL, NULL }
441 	};
442 	(void)_nsdispatch(NULL, dtab, NSDB_PASSWD, "setpwent", defaultsrc, 0);
443 }
444 
445 
446 int
447 setpassent(int stayopen)
448 {
449 #ifdef NS_CACHING
450 	static const nss_cache_info cache_info = NS_MP_CACHE_INFO_INITIALIZER(
451 		passwd, (void *)nss_lt_all,
452 		NULL, NULL);
453 #endif
454 
455 	static const ns_dtab dtab[] = {
456 		{ NSSRC_FILES, files_setpwent, (void *)SETPWENT },
457 #ifdef HESIOD
458 		{ NSSRC_DNS, dns_setpwent, (void *)SETPWENT },
459 #endif
460 #ifdef YP
461 		{ NSSRC_NIS, nis_setpwent, (void *)SETPWENT },
462 #endif
463 		{ NSSRC_COMPAT, compat_setpwent, (void *)SETPWENT },
464 #ifdef NS_CACHING
465 		NS_CACHE_CB(&cache_info)
466 #endif
467 		{ NULL, NULL, NULL }
468 	};
469 	(void)_nsdispatch(NULL, dtab, NSDB_PASSWD, "setpwent", defaultsrc,
470 	    stayopen);
471 	return (1);
472 }
473 
474 
475 void
476 endpwent(void)
477 {
478 #ifdef NS_CACHING
479 	static const nss_cache_info cache_info = NS_MP_CACHE_INFO_INITIALIZER(
480 		passwd, (void *)nss_lt_all,
481 		NULL, NULL);
482 #endif
483 
484 	static const ns_dtab dtab[] = {
485 		{ NSSRC_FILES, files_setpwent, (void *)ENDPWENT },
486 #ifdef HESIOD
487 		{ NSSRC_DNS, dns_setpwent, (void *)ENDPWENT },
488 #endif
489 #ifdef YP
490 		{ NSSRC_NIS, nis_setpwent, (void *)ENDPWENT },
491 #endif
492 		{ NSSRC_COMPAT, compat_setpwent, (void *)ENDPWENT },
493 #ifdef NS_CACHING
494 		NS_CACHE_CB(&cache_info)
495 #endif
496 		{ NULL, NULL, NULL }
497 	};
498 	(void)_nsdispatch(NULL, dtab, NSDB_PASSWD, "endpwent", defaultsrc);
499 }
500 
501 
502 int
503 getpwent_r(struct passwd *pwd, char *buffer, size_t bufsize,
504     struct passwd **result)
505 {
506 #ifdef NS_CACHING
507 	static const nss_cache_info cache_info = NS_MP_CACHE_INFO_INITIALIZER(
508 		passwd, (void *)nss_lt_all,
509 		pwd_marshal_func, pwd_unmarshal_func);
510 #endif
511 
512 	static const ns_dtab dtab[] = {
513 		{ NSSRC_FILES, files_passwd, (void *)nss_lt_all },
514 #ifdef HESIOD
515 		{ NSSRC_DNS, dns_passwd, (void *)nss_lt_all },
516 #endif
517 #ifdef YP
518 		{ NSSRC_NIS, nis_passwd, (void *)nss_lt_all },
519 #endif
520 		{ NSSRC_COMPAT, compat_passwd, (void *)nss_lt_all },
521 #ifdef NS_CACHING
522 		NS_CACHE_CB(&cache_info)
523 #endif
524 		{ NULL, NULL, NULL }
525 	};
526 	int	rv, ret_errno;
527 
528 	__pw_initpwd(pwd);
529 	ret_errno = 0;
530 	*result = NULL;
531 	rv = _nsdispatch(result, dtab, NSDB_PASSWD, "getpwent_r", defaultsrc,
532 	    pwd, buffer, bufsize, &ret_errno);
533 	if (rv == NS_SUCCESS)
534 		return (0);
535 	else
536 		return (ret_errno);
537 }
538 
539 
540 int
541 getpwnam_r(const char *name, struct passwd *pwd, char *buffer, size_t bufsize,
542     struct passwd **result)
543 {
544 #ifdef NS_CACHING
545 	static const nss_cache_info cache_info =
546     		NS_COMMON_CACHE_INFO_INITIALIZER(
547 		passwd, (void *)nss_lt_name,
548 		pwd_id_func, pwd_marshal_func, pwd_unmarshal_func);
549 #endif
550 
551 	static const ns_dtab dtab[] = {
552 		{ NSSRC_FILES, files_passwd, (void *)nss_lt_name },
553 #ifdef HESIOD
554 		{ NSSRC_DNS, dns_passwd, (void *)nss_lt_name },
555 #endif
556 #ifdef YP
557 		{ NSSRC_NIS, nis_passwd, (void *)nss_lt_name },
558 #endif
559 		{ NSSRC_COMPAT, compat_passwd, (void *)nss_lt_name },
560 #ifdef NS_CACHING
561 		NS_CACHE_CB(&cache_info)
562 #endif
563 		{ NULL, NULL, NULL }
564 	};
565 	int	rv, ret_errno;
566 
567 	__pw_initpwd(pwd);
568 	ret_errno = 0;
569 	*result = NULL;
570 	rv = _nsdispatch(result, dtab, NSDB_PASSWD, "getpwnam_r", defaultsrc,
571 	    name, pwd, buffer, bufsize, &ret_errno);
572 	if (rv == NS_SUCCESS)
573 		return (0);
574 	else
575 		return (ret_errno);
576 }
577 
578 
579 int
580 getpwuid_r(uid_t uid, struct passwd *pwd, char *buffer, size_t bufsize,
581     struct passwd **result)
582 {
583 #ifdef NS_CACHING
584 	static const nss_cache_info cache_info =
585     		NS_COMMON_CACHE_INFO_INITIALIZER(
586 		passwd, (void *)nss_lt_id,
587 		pwd_id_func, pwd_marshal_func, pwd_unmarshal_func);
588 #endif
589 
590 	static const ns_dtab dtab[] = {
591 		{ NSSRC_FILES, files_passwd, (void *)nss_lt_id },
592 #ifdef HESIOD
593 		{ NSSRC_DNS, dns_passwd, (void *)nss_lt_id },
594 #endif
595 #ifdef YP
596 		{ NSSRC_NIS, nis_passwd, (void *)nss_lt_id },
597 #endif
598 		{ NSSRC_COMPAT, compat_passwd, (void *)nss_lt_id },
599 #ifdef NS_CACHING
600 		NS_CACHE_CB(&cache_info)
601 #endif
602 		{ NULL, NULL, NULL }
603 	};
604 	int	rv, ret_errno;
605 
606 	__pw_initpwd(pwd);
607 	ret_errno = 0;
608 	*result = NULL;
609 	rv = _nsdispatch(result, dtab, NSDB_PASSWD, "getpwuid_r", defaultsrc,
610 	    uid, pwd, buffer, bufsize, &ret_errno);
611 	if (rv == NS_SUCCESS)
612 		return (0);
613 	else
614 		return (ret_errno);
615 }
616 
617 
618 static struct passwd	 pwd;
619 static char		*pwd_storage;
620 static size_t		 pwd_storage_size;
621 
622 
623 static struct passwd *
624 getpw(int (*fn)(union key, struct passwd *, char *, size_t, struct passwd **),
625     union key key)
626 {
627 	int		 rv;
628 	struct passwd	*res;
629 
630 	if (pwd_storage == NULL) {
631 		pwd_storage = malloc(PWD_STORAGE_INITIAL);
632 		if (pwd_storage == NULL)
633 			return (NULL);
634 		pwd_storage_size = PWD_STORAGE_INITIAL;
635 	}
636 	do {
637 		rv = fn(key, &pwd, pwd_storage, pwd_storage_size, &res);
638 		if (res == NULL && rv == ERANGE) {
639 			free(pwd_storage);
640 			if ((pwd_storage_size << 1) > PWD_STORAGE_MAX) {
641 				pwd_storage = NULL;
642 				errno = ERANGE;
643 				return (NULL);
644 			}
645 			pwd_storage_size <<= 1;
646 			pwd_storage = malloc(pwd_storage_size);
647 			if (pwd_storage == NULL)
648 				return (NULL);
649 		}
650 	} while (res == NULL && rv == ERANGE);
651 	if (rv != 0)
652 		errno = rv;
653 	return (res);
654 }
655 
656 
657 static int
658 wrap_getpwnam_r(union key key, struct passwd *pwd, char *buffer,
659     size_t bufsize, struct passwd **res)
660 {
661 	return (getpwnam_r(key.name, pwd, buffer, bufsize, res));
662 }
663 
664 
665 static int
666 wrap_getpwuid_r(union key key, struct passwd *pwd, char *buffer,
667     size_t bufsize, struct passwd **res)
668 {
669 	return (getpwuid_r(key.uid, pwd, buffer, bufsize, res));
670 }
671 
672 
673 static int
674 wrap_getpwent_r(union key key __unused, struct passwd *pwd, char *buffer,
675     size_t bufsize, struct passwd **res)
676 {
677 	return (getpwent_r(pwd, buffer, bufsize, res));
678 }
679 
680 
681 struct passwd *
682 getpwnam(const char *name)
683 {
684 	union key key;
685 
686 	key.name = name;
687 	return (getpw(wrap_getpwnam_r, key));
688 }
689 
690 
691 struct passwd *
692 getpwuid(uid_t uid)
693 {
694 	union key key;
695 
696 	key.uid = uid;
697 	return (getpw(wrap_getpwuid_r, key));
698 }
699 
700 
701 struct passwd *
702 getpwent(void)
703 {
704 	union key key;
705 
706 	key.uid = 0; /* not used */
707 	return (getpw(wrap_getpwent_r, key));
708 }
709 
710 
711 /*
712  * files backend
713  */
714 static DB *
715 pwdbopen(int *version)
716 {
717 	DB	*res;
718 	DBT	 key, entry;
719 	int	 rv;
720 
721 	if (geteuid() != 0 ||
722 	    (res = dbopen(_PATH_SMP_DB, O_RDONLY, 0, DB_HASH, NULL)) == NULL)
723 		res = dbopen(_PATH_MP_DB, O_RDONLY, 0, DB_HASH, NULL);
724 	if (res == NULL)
725 		return (NULL);
726 	key.data = _PWD_VERSION_KEY;
727 	key.size = strlen(_PWD_VERSION_KEY);
728 	rv = res->get(res, &key, &entry, 0);
729 	if (rv == 0)
730 		*version = *(unsigned char *)entry.data;
731 	else
732 		*version = 3;
733 	if (*version < 3 ||
734 	    *version >= nitems(pwdb_versions)) {
735 		syslog(LOG_CRIT, "Unsupported password database version %d",
736 		    *version);
737 		res->close(res);
738 		res = NULL;
739 	}
740 	return (res);
741 }
742 
743 
744 static void
745 files_endstate(void *p)
746 {
747 	DB	*db;
748 
749 	if (p == NULL)
750 		return;
751 	db = ((struct files_state *)p)->db;
752 	if (db != NULL)
753 		db->close(db);
754 	free(p);
755 }
756 
757 
758 static int
759 files_setpwent(void *retval, void *mdata, va_list ap)
760 {
761 	struct files_state	*st;
762 	int			 rv, stayopen;
763 
764 	rv = files_getstate(&st);
765 	if (rv != 0)
766 		return (NS_UNAVAIL);
767 	switch ((enum constants)mdata) {
768 	case SETPWENT:
769 		stayopen = va_arg(ap, int);
770 		st->keynum = 0;
771 		if (stayopen)
772 			st->db = pwdbopen(&st->version);
773 		st->stayopen = stayopen;
774 		break;
775 	case ENDPWENT:
776 		if (st->db != NULL) {
777 			(void)st->db->close(st->db);
778 			st->db = NULL;
779 		}
780 		break;
781 	default:
782 		break;
783 	}
784 	return (NS_UNAVAIL);
785 }
786 
787 
788 static int
789 files_passwd(void *retval, void *mdata, va_list ap)
790 {
791 	char			 keybuf[MAXLOGNAME + 1];
792 	DBT			 key, entry;
793 	struct files_state	*st;
794 	enum nss_lookup_type	 how;
795 	const char		*name;
796 	struct passwd		*pwd;
797 	char			*buffer;
798 	size_t			 bufsize, namesize;
799 	uid_t			 uid;
800 	uint32_t		 store;
801 	int			 rv, stayopen = 0, *errnop;
802 
803 	name = NULL;
804 	uid = (uid_t)-1;
805 	how = (enum nss_lookup_type)mdata;
806 	switch (how) {
807 	case nss_lt_name:
808 		name = va_arg(ap, const char *);
809 		keybuf[0] = _PW_KEYBYNAME;
810 		break;
811 	case nss_lt_id:
812 		uid = va_arg(ap, uid_t);
813 		keybuf[0] = _PW_KEYBYUID;
814 		break;
815 	case nss_lt_all:
816 		keybuf[0] = _PW_KEYBYNUM;
817 		break;
818 	default:
819 		rv = NS_NOTFOUND;
820 		goto fin;
821 	}
822 	pwd = va_arg(ap, struct passwd *);
823 	buffer = va_arg(ap, char *);
824 	bufsize = va_arg(ap, size_t);
825 	errnop = va_arg(ap, int *);
826 	*errnop = files_getstate(&st);
827 	if (*errnop != 0)
828 		return (NS_UNAVAIL);
829 	if (how == nss_lt_all && st->keynum < 0) {
830 		rv = NS_NOTFOUND;
831 		goto fin;
832 	}
833 	if (st->db == NULL &&
834 	    (st->db = pwdbopen(&st->version)) == NULL) {
835 		*errnop = errno;
836 		rv = NS_UNAVAIL;
837 		goto fin;
838 	}
839 	if (how == nss_lt_all)
840 		stayopen = 1;
841 	else
842 		stayopen = st->stayopen;
843 	key.data = keybuf;
844 	do {
845 		switch (how) {
846 		case nss_lt_name:
847 			/* MAXLOGNAME includes NUL byte, but we do not
848 			 * include the NUL byte in the key.
849 			 */
850 			namesize = strlcpy(&keybuf[1], name, sizeof(keybuf)-1);
851 			if (namesize >= sizeof(keybuf)-1) {
852 				*errnop = EINVAL;
853 				rv = NS_NOTFOUND;
854 				goto fin;
855 			}
856 			key.size = namesize + 1;
857 			break;
858 		case nss_lt_id:
859 			if (st->version < _PWD_CURRENT_VERSION) {
860 				memcpy(&keybuf[1], &uid, sizeof(uid));
861 				key.size = sizeof(uid) + 1;
862 			} else {
863 				store = htonl(uid);
864 				memcpy(&keybuf[1], &store, sizeof(store));
865 				key.size = sizeof(store) + 1;
866 			}
867 			break;
868 		case nss_lt_all:
869 			st->keynum++;
870 			if (st->version < _PWD_CURRENT_VERSION) {
871 				memcpy(&keybuf[1], &st->keynum,
872 				    sizeof(st->keynum));
873 				key.size = sizeof(st->keynum) + 1;
874 			} else {
875 				store = htonl(st->keynum);
876 				memcpy(&keybuf[1], &store, sizeof(store));
877 				key.size = sizeof(store) + 1;
878 			}
879 			break;
880 		}
881 		keybuf[0] = _PW_VERSIONED(keybuf[0], st->version);
882 		rv = st->db->get(st->db, &key, &entry, 0);
883 		if (rv < 0 || rv > 1) { /* should never return > 1 */
884 			*errnop = errno;
885 			rv = NS_UNAVAIL;
886 			goto fin;
887 		} else if (rv == 1) {
888 			if (how == nss_lt_all)
889 				st->keynum = -1;
890 			rv = NS_NOTFOUND;
891 			goto fin;
892 		}
893 		rv = pwdb_versions[st->version].match(entry.data, entry.size,
894 		    how, name, uid);
895 		if (rv != NS_SUCCESS)
896 			continue;
897 		if (entry.size > bufsize) {
898 			*errnop = ERANGE;
899 			rv = NS_RETURN;
900 			break;
901 		}
902 		memcpy(buffer, entry.data, entry.size);
903 		rv = pwdb_versions[st->version].parse(buffer, entry.size, pwd,
904 		    errnop);
905 	} while (how == nss_lt_all && !(rv & NS_TERMINATE));
906 fin:
907 	if (st->db != NULL && !stayopen) {
908 		(void)st->db->close(st->db);
909 		st->db = NULL;
910 	}
911 	if (rv == NS_SUCCESS) {
912 		pwd->pw_fields &= ~_PWF_SOURCE;
913 		pwd->pw_fields |= _PWF_FILES;
914 		if (retval != NULL)
915 			*(struct passwd **)retval = pwd;
916 	}
917 	return (rv);
918 }
919 
920 
921 static int
922 pwdb_match_entry_v3(char *entry, size_t entrysize, enum nss_lookup_type how,
923     const char *name, uid_t uid)
924 {
925 	const char	*p, *eom;
926 	uid_t		 uid2;
927 
928 	eom = &entry[entrysize];
929 	for (p = entry; p < eom; p++)
930 		if (*p == '\0')
931 			break;
932 	if (*p != '\0')
933 		return (NS_NOTFOUND);
934 	if (how == nss_lt_all)
935 		return (NS_SUCCESS);
936 	if (how == nss_lt_name)
937 		return (strcmp(name, entry) == 0 ? NS_SUCCESS : NS_NOTFOUND);
938 	for (p++; p < eom; p++)
939 		if (*p == '\0')
940 			break;
941 	if (*p != '\0' || (++p) + sizeof(uid) >= eom)
942 		return (NS_NOTFOUND);
943 	memcpy(&uid2, p, sizeof(uid2));
944 	return (uid == uid2 ? NS_SUCCESS : NS_NOTFOUND);
945 }
946 
947 
948 static int
949 pwdb_parse_entry_v3(char *buffer, size_t bufsize, struct passwd *pwd,
950     int *errnop)
951 {
952 	char		*p, *eom;
953 	int32_t		 pw_change, pw_expire;
954 
955 	/* THIS CODE MUST MATCH THAT IN pwd_mkdb. */
956 	p = buffer;
957 	eom = &buffer[bufsize];
958 #define STRING(field)	do {			\
959 		(field) = p;			\
960 		while (p < eom && *p != '\0')	\
961 			p++;			\
962 		if (p >= eom)			\
963 			return (NS_NOTFOUND);	\
964 		p++;				\
965 	} while (0)
966 #define SCALAR(field)	do {				\
967 		if (p + sizeof(field) > eom)		\
968 			return (NS_NOTFOUND);		\
969 		memcpy(&(field), p, sizeof(field));	\
970 		p += sizeof(field);			\
971 	} while (0)
972 	STRING(pwd->pw_name);
973 	STRING(pwd->pw_passwd);
974 	SCALAR(pwd->pw_uid);
975 	SCALAR(pwd->pw_gid);
976 	SCALAR(pw_change);
977 	STRING(pwd->pw_class);
978 	STRING(pwd->pw_gecos);
979 	STRING(pwd->pw_dir);
980 	STRING(pwd->pw_shell);
981 	SCALAR(pw_expire);
982 	SCALAR(pwd->pw_fields);
983 #undef STRING
984 #undef SCALAR
985 	pwd->pw_change = pw_change;
986 	pwd->pw_expire = pw_expire;
987 	return (NS_SUCCESS);
988 }
989 
990 
991 static int
992 pwdb_match_entry_v4(char *entry, size_t entrysize, enum nss_lookup_type how,
993     const char *name, uid_t uid)
994 {
995 	const char	*p, *eom;
996 	uint32_t	 uid2;
997 
998 	eom = &entry[entrysize];
999 	for (p = entry; p < eom; p++)
1000 		if (*p == '\0')
1001 			break;
1002 	if (*p != '\0')
1003 		return (NS_NOTFOUND);
1004 	if (how == nss_lt_all)
1005 		return (NS_SUCCESS);
1006 	if (how == nss_lt_name)
1007 		return (strcmp(name, entry) == 0 ? NS_SUCCESS : NS_NOTFOUND);
1008 	for (p++; p < eom; p++)
1009 		if (*p == '\0')
1010 			break;
1011 	if (*p != '\0' || (++p) + sizeof(uid) >= eom)
1012 		return (NS_NOTFOUND);
1013 	memcpy(&uid2, p, sizeof(uid2));
1014 	uid2 = ntohl(uid2);
1015 	return (uid == (uid_t)uid2 ? NS_SUCCESS : NS_NOTFOUND);
1016 }
1017 
1018 
1019 static int
1020 pwdb_parse_entry_v4(char *buffer, size_t bufsize, struct passwd *pwd,
1021     int *errnop)
1022 {
1023 	char		*p, *eom;
1024 	uint32_t	 n;
1025 
1026 	/* THIS CODE MUST MATCH THAT IN pwd_mkdb. */
1027 	p = buffer;
1028 	eom = &buffer[bufsize];
1029 #define STRING(field)	do {			\
1030 		(field) = p;			\
1031 		while (p < eom && *p != '\0')	\
1032 			p++;			\
1033 		if (p >= eom)			\
1034 			return (NS_NOTFOUND);	\
1035 		p++;				\
1036 	} while (0)
1037 #define SCALAR(field)	do {				\
1038 		if (p + sizeof(n) > eom)		\
1039 			return (NS_NOTFOUND);		\
1040 		memcpy(&n, p, sizeof(n));		\
1041 		(field) = ntohl(n);			\
1042 		p += sizeof(n);				\
1043 	} while (0)
1044 	STRING(pwd->pw_name);
1045 	STRING(pwd->pw_passwd);
1046 	SCALAR(pwd->pw_uid);
1047 	SCALAR(pwd->pw_gid);
1048 	SCALAR(pwd->pw_change);
1049 	STRING(pwd->pw_class);
1050 	STRING(pwd->pw_gecos);
1051 	STRING(pwd->pw_dir);
1052 	STRING(pwd->pw_shell);
1053 	SCALAR(pwd->pw_expire);
1054 	SCALAR(pwd->pw_fields);
1055 #undef STRING
1056 #undef SCALAR
1057 	return (NS_SUCCESS);
1058 }
1059 
1060 
1061 #ifdef HESIOD
1062 /*
1063  * dns backend
1064  */
1065 static void
1066 dns_endstate(void *p)
1067 {
1068 	free(p);
1069 }
1070 
1071 
1072 static int
1073 dns_setpwent(void *retval, void *mdata, va_list ap)
1074 {
1075 	struct dns_state	*st;
1076 	int			 rv;
1077 
1078 	rv = dns_getstate(&st);
1079 	if (rv != 0)
1080 		return (NS_UNAVAIL);
1081 	st->counter = 0;
1082 	return (NS_UNAVAIL);
1083 }
1084 
1085 
1086 static int
1087 dns_passwd(void *retval, void *mdata, va_list ap)
1088 {
1089 	char			 buf[HESIOD_NAME_MAX];
1090 	struct dns_state	*st;
1091 	struct passwd		*pwd;
1092 	const char		*name, *label;
1093 	void			*ctx;
1094 	char			*buffer, **hes;
1095 	size_t			 bufsize, linesize;
1096 	uid_t			 uid;
1097 	enum nss_lookup_type	 how;
1098 	int			 rv, *errnop;
1099 
1100 	ctx = NULL;
1101 	hes = NULL;
1102 	name = NULL;
1103 	uid = (uid_t)-1;
1104 	how = (enum nss_lookup_type)mdata;
1105 	switch (how) {
1106 	case nss_lt_name:
1107 		name = va_arg(ap, const char *);
1108 		break;
1109 	case nss_lt_id:
1110 		uid = va_arg(ap, uid_t);
1111 		break;
1112 	case nss_lt_all:
1113 		break;
1114 	}
1115 	pwd     = va_arg(ap, struct passwd *);
1116 	buffer  = va_arg(ap, char *);
1117 	bufsize = va_arg(ap, size_t);
1118 	errnop  = va_arg(ap, int *);
1119 	*errnop = dns_getstate(&st);
1120 	if (*errnop != 0)
1121 		return (NS_UNAVAIL);
1122 	if (hesiod_init(&ctx) != 0) {
1123 		*errnop = errno;
1124 		rv = NS_UNAVAIL;
1125 		goto fin;
1126 	}
1127 	do {
1128 		rv = NS_NOTFOUND;
1129 		switch (how) {
1130 		case nss_lt_name:
1131 			label = name;
1132 			break;
1133 		case nss_lt_id:
1134 			if (snprintf(buf, sizeof(buf), "%lu",
1135 			    (unsigned long)uid) >= sizeof(buf))
1136 				goto fin;
1137 			label = buf;
1138 			break;
1139 		case nss_lt_all:
1140 			if (st->counter < 0)
1141 				goto fin;
1142 			if (snprintf(buf, sizeof(buf), "passwd-%ld",
1143 			    st->counter++) >= sizeof(buf))
1144 				goto fin;
1145 			label = buf;
1146 			break;
1147 		}
1148 		hes = hesiod_resolve(ctx, label,
1149 		    how == nss_lt_id ? "uid" : "passwd");
1150 		if (hes == NULL) {
1151 			if (how == nss_lt_all)
1152 				st->counter = -1;
1153 			if (errno != ENOENT)
1154 				*errnop = errno;
1155 			goto fin;
1156 		}
1157 		rv = __pw_match_entry(hes[0], strlen(hes[0]), how, name, uid);
1158 		if (rv != NS_SUCCESS) {
1159 			hesiod_free_list(ctx, hes);
1160 			hes = NULL;
1161 			continue;
1162 		}
1163 		linesize = strlcpy(buffer, hes[0], bufsize);
1164 		if (linesize >= bufsize) {
1165 			*errnop = ERANGE;
1166 			rv = NS_RETURN;
1167 			continue;
1168 		}
1169 		hesiod_free_list(ctx, hes);
1170 		hes = NULL;
1171 		rv = __pw_parse_entry(buffer, bufsize, pwd, 0, errnop);
1172 	} while (how == nss_lt_all && !(rv & NS_TERMINATE));
1173 fin:
1174 	if (hes != NULL)
1175 		hesiod_free_list(ctx, hes);
1176 	if (ctx != NULL)
1177 		hesiod_end(ctx);
1178 	if (rv == NS_SUCCESS) {
1179 		pwd->pw_fields &= ~_PWF_SOURCE;
1180 		pwd->pw_fields |= _PWF_HESIOD;
1181 		if (retval != NULL)
1182 			*(struct passwd **)retval = pwd;
1183 	}
1184 	return (rv);
1185 }
1186 #endif /* HESIOD */
1187 
1188 
1189 #ifdef YP
1190 /*
1191  * nis backend
1192  */
1193 static void
1194 nis_endstate(void *p)
1195 {
1196 	free(((struct nis_state *)p)->key);
1197 	free(p);
1198 }
1199 
1200 /*
1201  * Test for the presence of special FreeBSD-specific master.passwd.by*
1202  * maps. We do this using yp_order(). If it fails, then either the server
1203  * doesn't have the map, or the YPPROC_ORDER procedure isn't supported by
1204  * the server (Sun NIS+ servers in YP compat mode behave this way). If
1205  * the master.passwd.by* maps don't exist, then let the lookup routine try
1206  * the regular passwd.by* maps instead. If the lookup routine fails, it
1207  * can return an error as needed.
1208  */
1209 static int
1210 nis_map(char *domain, enum nss_lookup_type how, char *buffer, size_t bufsize,
1211     int *master)
1212 {
1213 	int	rv, order;
1214 
1215 	*master = 0;
1216 	if (geteuid() == 0) {
1217 		if (snprintf(buffer, bufsize, "master.passwd.by%s",
1218 		    (how == nss_lt_id) ? "uid" : "name") >= bufsize)
1219 			return (NS_UNAVAIL);
1220 		rv = yp_order(domain, buffer, &order);
1221 		if (rv == 0) {
1222 			*master = 1;
1223 			return (NS_SUCCESS);
1224 		}
1225 	}
1226 
1227 	if (snprintf(buffer, bufsize, "passwd.by%s",
1228 	    (how == nss_lt_id) ? "uid" : "name") >= bufsize)
1229 		return (NS_UNAVAIL);
1230 
1231 	return (NS_SUCCESS);
1232 }
1233 
1234 
1235 static int
1236 nis_adjunct(char *domain, const char *name, char *buffer, size_t bufsize)
1237 {
1238 	int	 rv;
1239 	char	*result, *p, *q, *eor;
1240 	int	 resultlen;
1241 
1242 	result = NULL;
1243 	rv = yp_match(domain, "passwd.adjunct.byname", name, strlen(name),
1244 	    &result, &resultlen);
1245 	if (rv != 0)
1246 		rv = 1;
1247 	else {
1248 		eor = &result[resultlen];
1249 		p = memchr(result, ':', eor - result);
1250 		if (p != NULL && ++p < eor &&
1251 		    (q = memchr(p, ':', eor - p)) != NULL) {
1252 			if (q - p >= bufsize)
1253 				rv = -1;
1254 			else {
1255 				memcpy(buffer, p, q - p);
1256 				buffer[q - p] ='\0';
1257 			}
1258 		} else
1259 			rv = 1;
1260 	}
1261 	free(result);
1262 	return (rv);
1263 }
1264 
1265 
1266 static int
1267 nis_setpwent(void *retval, void *mdata, va_list ap)
1268 {
1269 	struct nis_state	*st;
1270 	int			 rv;
1271 
1272 	rv = nis_getstate(&st);
1273 	if (rv != 0)
1274 		return (NS_UNAVAIL);
1275 	st->done = 0;
1276 	free(st->key);
1277 	st->key = NULL;
1278 	return (NS_UNAVAIL);
1279 }
1280 
1281 
1282 static int
1283 nis_passwd(void *retval, void *mdata, va_list ap)
1284 {
1285 	char		 map[YPMAXMAP];
1286 	struct nis_state *st;
1287 	struct passwd	*pwd;
1288 	const char	*name;
1289 	char		*buffer, *key, *result;
1290 	size_t		 bufsize;
1291 	uid_t		 uid;
1292 	enum nss_lookup_type how;
1293 	int		*errnop, keylen, resultlen, rv, master;
1294 
1295 	name = NULL;
1296 	uid = (uid_t)-1;
1297 	how = (enum nss_lookup_type)mdata;
1298 	switch (how) {
1299 	case nss_lt_name:
1300 		name = va_arg(ap, const char *);
1301 		break;
1302 	case nss_lt_id:
1303 		uid = va_arg(ap, uid_t);
1304 		break;
1305 	case nss_lt_all:
1306 		break;
1307 	}
1308 	pwd     = va_arg(ap, struct passwd *);
1309 	buffer  = va_arg(ap, char *);
1310 	bufsize = va_arg(ap, size_t);
1311 	errnop  = va_arg(ap, int *);
1312 	*errnop = nis_getstate(&st);
1313 	if (*errnop != 0)
1314 		return (NS_UNAVAIL);
1315 	if (st->domain[0] == '\0') {
1316 		if (getdomainname(st->domain, sizeof(st->domain)) != 0) {
1317 			*errnop = errno;
1318 			return (NS_UNAVAIL);
1319 		}
1320 	}
1321 	rv = nis_map(st->domain, how, map, sizeof(map), &master);
1322 	if (rv != NS_SUCCESS)
1323 		return (rv);
1324 	result = NULL;
1325 	do {
1326 		rv = NS_NOTFOUND;
1327 		switch (how) {
1328 		case nss_lt_name:
1329 			if (strlcpy(buffer, name, bufsize) >= bufsize)
1330 				goto erange;
1331 			break;
1332 		case nss_lt_id:
1333 			if (snprintf(buffer, bufsize, "%lu",
1334 			    (unsigned long)uid) >= bufsize)
1335 				goto erange;
1336 			break;
1337 		case nss_lt_all:
1338 			if (st->done)
1339 				goto fin;
1340 			break;
1341 		}
1342 		result = NULL;
1343 		if (how == nss_lt_all) {
1344 			if (st->key == NULL)
1345 				rv = yp_first(st->domain, map, &st->key,
1346 				    &st->keylen, &result, &resultlen);
1347 			else {
1348 				key = st->key;
1349 				keylen = st->keylen;
1350 				st->key = NULL;
1351 				rv = yp_next(st->domain, map, key, keylen,
1352 				    &st->key, &st->keylen, &result,
1353 				    &resultlen);
1354 				free(key);
1355 			}
1356 			if (rv != 0) {
1357 				free(result);
1358 				free(st->key);
1359 				st->key = NULL;
1360 				if (rv == YPERR_NOMORE)
1361 					st->done = 1;
1362 				else
1363 					rv = NS_UNAVAIL;
1364 				goto fin;
1365 			}
1366 		} else {
1367 			rv = yp_match(st->domain, map, buffer, strlen(buffer),
1368 			    &result, &resultlen);
1369 			if (rv == YPERR_KEY) {
1370 				rv = NS_NOTFOUND;
1371 				continue;
1372 			} else if (rv != 0) {
1373 				free(result);
1374 				rv = NS_UNAVAIL;
1375 				continue;
1376 			}
1377 		}
1378 		if (resultlen >= bufsize) {
1379 			free(result);
1380 			goto erange;
1381 		}
1382 		memcpy(buffer, result, resultlen);
1383 		buffer[resultlen] = '\0';
1384 		free(result);
1385 		rv = __pw_match_entry(buffer, resultlen, how, name, uid);
1386 		if (rv == NS_SUCCESS)
1387 			rv = __pw_parse_entry(buffer, resultlen, pwd, master,
1388 			    errnop);
1389 	} while (how == nss_lt_all && !(rv & NS_TERMINATE));
1390 fin:
1391 	if (rv == NS_SUCCESS) {
1392 		if (strstr(pwd->pw_passwd, "##") != NULL) {
1393 			rv = nis_adjunct(st->domain, pwd->pw_name,
1394 			    &buffer[resultlen+1], bufsize-resultlen-1);
1395 			if (rv < 0)
1396 				goto erange;
1397 			else if (rv == 0)
1398 				pwd->pw_passwd = &buffer[resultlen+1];
1399 		}
1400 		pwd->pw_fields &= ~_PWF_SOURCE;
1401 		pwd->pw_fields |= _PWF_NIS;
1402 		if (retval != NULL)
1403 			*(struct passwd **)retval = pwd;
1404 		rv = NS_SUCCESS;
1405 	}
1406 	return (rv);
1407 erange:
1408 	*errnop = ERANGE;
1409 	return (NS_RETURN);
1410 }
1411 #endif /* YP */
1412 
1413 
1414 /*
1415  * compat backend
1416  */
1417 static void
1418 compat_clear_template(struct passwd *template)
1419 {
1420 
1421 	free(template->pw_passwd);
1422 	free(template->pw_gecos);
1423 	free(template->pw_dir);
1424 	free(template->pw_shell);
1425 	memset(template, 0, sizeof(*template));
1426 }
1427 
1428 
1429 static int
1430 compat_set_template(struct passwd *src, struct passwd *template)
1431 {
1432 
1433 	compat_clear_template(template);
1434 #ifdef PW_OVERRIDE_PASSWD
1435 	if ((src->pw_fields & _PWF_PASSWD) &&
1436 	    (template->pw_passwd = strdup(src->pw_passwd)) == NULL)
1437 		goto enomem;
1438 #endif
1439 	if (src->pw_fields & _PWF_UID)
1440 		template->pw_uid = src->pw_uid;
1441 	if (src->pw_fields & _PWF_GID)
1442 		template->pw_gid = src->pw_gid;
1443 	if ((src->pw_fields & _PWF_GECOS) &&
1444 	    (template->pw_gecos = strdup(src->pw_gecos)) == NULL)
1445 		goto enomem;
1446 	if ((src->pw_fields & _PWF_DIR) &&
1447 	    (template->pw_dir = strdup(src->pw_dir)) == NULL)
1448 		goto enomem;
1449 	if ((src->pw_fields & _PWF_SHELL) &&
1450 	    (template->pw_shell = strdup(src->pw_shell)) == NULL)
1451 		goto enomem;
1452 	template->pw_fields = src->pw_fields;
1453 	return (0);
1454 enomem:
1455 	syslog(LOG_ERR, "getpwent memory allocation failure");
1456 	return (-1);
1457 }
1458 
1459 
1460 static int
1461 compat_use_template(struct passwd *pwd, struct passwd *template, char *buffer,
1462     size_t bufsize)
1463 {
1464 	struct passwd hold;
1465 	char	*copy, *p, *q, *eob;
1466 	size_t	 n;
1467 
1468 	/* We cannot know the layout of the password fields in `buffer',
1469 	 * so we have to copy everything.
1470 	 */
1471 	if (template->pw_fields == 0) /* nothing to fill-in */
1472 		return (0);
1473 	n = 0;
1474 	n += pwd->pw_name != NULL ? strlen(pwd->pw_name) + 1 : 0;
1475 	n += pwd->pw_passwd != NULL ? strlen(pwd->pw_passwd) + 1 : 0;
1476 	n += pwd->pw_class != NULL ? strlen(pwd->pw_class) + 1 : 0;
1477 	n += pwd->pw_gecos != NULL ? strlen(pwd->pw_gecos) + 1 : 0;
1478 	n += pwd->pw_dir != NULL ? strlen(pwd->pw_dir) + 1 : 0;
1479 	n += pwd->pw_shell != NULL ? strlen(pwd->pw_shell) + 1 : 0;
1480 	copy = malloc(n);
1481 	if (copy == NULL) {
1482 		syslog(LOG_ERR, "getpwent memory allocation failure");
1483 		return (ENOMEM);
1484 	}
1485 	p = copy;
1486 	eob = &copy[n];
1487 #define COPY(field) do {				\
1488 	if (pwd->field == NULL)				\
1489 		hold.field = NULL;			\
1490 	else {						\
1491 		hold.field = p;				\
1492 		p += strlcpy(p, pwd->field, eob-p) + 1;	\
1493 	}						\
1494 } while (0)
1495 	COPY(pw_name);
1496 	COPY(pw_passwd);
1497 	COPY(pw_class);
1498 	COPY(pw_gecos);
1499 	COPY(pw_dir);
1500 	COPY(pw_shell);
1501 #undef COPY
1502 	p = buffer;
1503 	eob = &buffer[bufsize];
1504 #define COPY(field, flag) do {						 \
1505 	q = (template->pw_fields & flag) ? template->field : hold.field; \
1506 	if (q == NULL)							 \
1507 		pwd->field = NULL;					 \
1508 	else {								 \
1509 		pwd->field = p;						 \
1510 		if ((n = strlcpy(p, q, eob-p)) >= eob-p) {		 \
1511 			free(copy);					 \
1512 			return (ERANGE);				 \
1513 		}							 \
1514 		p += n + 1;						 \
1515 	}								 \
1516 } while (0)
1517 	COPY(pw_name, 0);
1518 #ifdef PW_OVERRIDE_PASSWD
1519 	COPY(pw_passwd, _PWF_PASSWD);
1520 #else
1521 	COPY(pw_passwd, 0);
1522 #endif
1523 	COPY(pw_class, 0);
1524 	COPY(pw_gecos, _PWF_GECOS);
1525 	COPY(pw_dir, _PWF_DIR);
1526 	COPY(pw_shell, _PWF_SHELL);
1527 #undef COPY
1528 #define COPY(field, flag) do {			\
1529 	if (template->pw_fields & flag)		\
1530 		pwd->field = template->field;	\
1531 } while (0)
1532 	COPY(pw_uid, _PWF_UID);
1533 	COPY(pw_gid, _PWF_GID);
1534 #undef COPY
1535 	free(copy);
1536 	return (0);
1537 }
1538 
1539 
1540 static int
1541 compat_exclude(const char *name, DB **db)
1542 {
1543 	DBT	key, data;
1544 
1545 	if (*db == NULL &&
1546 	    (*db = dbopen(NULL, O_RDWR, 600, DB_HASH, 0)) == NULL)
1547 		return (errno);
1548 	key.size = strlen(name);
1549 	key.data = (char *)name;
1550 	data.size = 0;
1551 	data.data = NULL;
1552 
1553 	if ((*db)->put(*db, &key, &data, 0) == -1)
1554 		return (errno);
1555 	return (0);
1556 }
1557 
1558 
1559 static int
1560 compat_is_excluded(const char *name, DB *db)
1561 {
1562 	DBT	key, data;
1563 
1564 	if (db == NULL)
1565 		return (0);
1566 	key.size = strlen(name);
1567 	key.data = (char *)name;
1568 	return (db->get(db, &key, &data, 0) == 0);
1569 }
1570 
1571 
1572 static int
1573 compat_redispatch(struct compat_state *st, enum nss_lookup_type how,
1574     enum nss_lookup_type lookup_how, const char *name, const char *lookup_name,
1575     uid_t uid, struct passwd *pwd, char *buffer, size_t bufsize, int *errnop)
1576 {
1577 	static const ns_src compatsrc[] = {
1578 #ifdef YP
1579 		{ NSSRC_NIS, NS_SUCCESS },
1580 #endif
1581 		{ NULL, 0 }
1582 	};
1583 	ns_dtab dtab[] = {
1584 #ifdef YP
1585 		{ NSSRC_NIS, nis_passwd, NULL },
1586 #endif
1587 #ifdef HESIOD
1588 		{ NSSRC_DNS, dns_passwd, NULL },
1589 #endif
1590 		{ NULL, NULL, NULL }
1591 	};
1592 	void		*discard;
1593 	int		 e, i, rv;
1594 
1595 	for (i = 0; i < (int)(nitems(dtab) - 1); i++)
1596 		dtab[i].mdata = (void *)lookup_how;
1597 more:
1598 	__pw_initpwd(pwd);
1599 	switch (lookup_how) {
1600 	case nss_lt_all:
1601 		rv = _nsdispatch(&discard, dtab, NSDB_PASSWD_COMPAT,
1602 		    "getpwent_r", compatsrc, pwd, buffer, bufsize,
1603 		    errnop);
1604 		break;
1605 	case nss_lt_id:
1606 		rv = _nsdispatch(&discard, dtab, NSDB_PASSWD_COMPAT,
1607 		    "getpwuid_r", compatsrc, uid, pwd, buffer,
1608 		    bufsize, errnop);
1609 		break;
1610 	case nss_lt_name:
1611 		rv = _nsdispatch(&discard, dtab, NSDB_PASSWD_COMPAT,
1612 		    "getpwnam_r", compatsrc, lookup_name, pwd, buffer,
1613 		    bufsize, errnop);
1614 		break;
1615 	default:
1616 		return (NS_UNAVAIL);
1617 	}
1618 	if (rv != NS_SUCCESS)
1619 		return (rv);
1620 	if (compat_is_excluded(pwd->pw_name, st->exclude)) {
1621 		if (how == nss_lt_all)
1622 			goto more;
1623 		return (NS_NOTFOUND);
1624 	}
1625 	e = compat_use_template(pwd, &st->template, buffer, bufsize);
1626 	if (e != 0) {
1627 		*errnop = e;
1628 		if (e == ERANGE)
1629 			return (NS_RETURN);
1630 		else
1631 			return (NS_UNAVAIL);
1632 	}
1633 	switch (how) {
1634 	case nss_lt_name:
1635 		if (strcmp(name, pwd->pw_name) != 0)
1636 			return (NS_NOTFOUND);
1637 		break;
1638 	case nss_lt_id:
1639 		if (uid != pwd->pw_uid)
1640 			return (NS_NOTFOUND);
1641 		break;
1642 	default:
1643 		break;
1644 	}
1645 	return (NS_SUCCESS);
1646 }
1647 
1648 
1649 static void
1650 compat_endstate(void *p)
1651 {
1652 	struct compat_state *st;
1653 
1654 	if (p == NULL)
1655 		return;
1656 	st = (struct compat_state *)p;
1657 	if (st->db != NULL)
1658 		st->db->close(st->db);
1659 	if (st->exclude != NULL)
1660 		st->exclude->close(st->exclude);
1661 	compat_clear_template(&st->template);
1662 	free(p);
1663 }
1664 
1665 
1666 static int
1667 compat_setpwent(void *retval, void *mdata, va_list ap)
1668 {
1669 	static const ns_src compatsrc[] = {
1670 #ifdef YP
1671 		{ NSSRC_NIS, NS_SUCCESS },
1672 #endif
1673 		{ NULL, 0 }
1674 	};
1675 	ns_dtab dtab[] = {
1676 #ifdef YP
1677 		{ NSSRC_NIS, nis_setpwent, NULL },
1678 #endif
1679 #ifdef HESIOD
1680 		{ NSSRC_DNS, dns_setpwent, NULL },
1681 #endif
1682 		{ NULL, NULL, NULL }
1683 	};
1684 	struct compat_state	*st;
1685 	int			 rv, stayopen;
1686 
1687 #define set_setent(x, y) do {	 				\
1688 	int i;							\
1689 	for (i = 0; i < (int)(nitems(x) - 1); i++)		\
1690 		x[i].mdata = (void *)y;				\
1691 } while (0)
1692 
1693 	rv = compat_getstate(&st);
1694 	if (rv != 0)
1695 		return (NS_UNAVAIL);
1696 	switch ((enum constants)mdata) {
1697 	case SETPWENT:
1698 		stayopen = va_arg(ap, int);
1699 		st->keynum = 0;
1700 		if (stayopen)
1701 			st->db = pwdbopen(&st->version);
1702 		st->stayopen = stayopen;
1703 		set_setent(dtab, mdata);
1704 		(void)_nsdispatch(NULL, dtab, NSDB_PASSWD_COMPAT, "setpwent",
1705 		    compatsrc, 0);
1706 		break;
1707 	case ENDPWENT:
1708 		if (st->db != NULL) {
1709 			(void)st->db->close(st->db);
1710 			st->db = NULL;
1711 		}
1712 		set_setent(dtab, mdata);
1713 		(void)_nsdispatch(NULL, dtab, NSDB_PASSWD_COMPAT, "endpwent",
1714 		    compatsrc, 0);
1715 		break;
1716 	default:
1717 		break;
1718 	}
1719 	return (NS_UNAVAIL);
1720 #undef set_setent
1721 }
1722 
1723 
1724 static int
1725 compat_passwd(void *retval, void *mdata, va_list ap)
1726 {
1727 	char			 keybuf[MAXLOGNAME + 1];
1728 	DBT			 key, entry;
1729 	struct compat_state	*st;
1730 	enum nss_lookup_type	 how;
1731 	const char		*name;
1732 	struct passwd		*pwd;
1733 	char			*buffer, *pw_name;
1734 	char			*host, *user, *domain;
1735 	size_t			 bufsize;
1736 	uid_t			 uid;
1737 	uint32_t		 store;
1738 	int			 rv, from_compat, stayopen, *errnop;
1739 
1740 	from_compat = 0;
1741 	name = NULL;
1742 	uid = (uid_t)-1;
1743 	how = (enum nss_lookup_type)mdata;
1744 	switch (how) {
1745 	case nss_lt_name:
1746 		name = va_arg(ap, const char *);
1747 		break;
1748 	case nss_lt_id:
1749 		uid = va_arg(ap, uid_t);
1750 		break;
1751 	case nss_lt_all:
1752 		break;
1753 	default:
1754 		rv = NS_NOTFOUND;
1755 		goto fin;
1756 	}
1757 	pwd = va_arg(ap, struct passwd *);
1758 	buffer = va_arg(ap, char *);
1759 	bufsize = va_arg(ap, size_t);
1760 	errnop = va_arg(ap, int *);
1761 	*errnop = compat_getstate(&st);
1762 	if (*errnop != 0)
1763 		return (NS_UNAVAIL);
1764 	if (how == nss_lt_all && st->keynum < 0) {
1765 		rv = NS_NOTFOUND;
1766 		goto fin;
1767 	}
1768 	if (st->db == NULL &&
1769 	    (st->db = pwdbopen(&st->version)) == NULL) {
1770 		*errnop = errno;
1771 		rv = NS_UNAVAIL;
1772 		goto fin;
1773 	}
1774 	if (how == nss_lt_all) {
1775 		if (st->keynum < 0) {
1776 			rv = NS_NOTFOUND;
1777 			goto fin;
1778 		}
1779 		stayopen = 1;
1780 	} else {
1781 		st->keynum = 0;
1782 		stayopen = st->stayopen;
1783 	}
1784 docompat:
1785 	rv = NS_NOTFOUND;
1786 	switch (st->compat) {
1787 	case COMPAT_MODE_ALL:
1788 		rv = compat_redispatch(st, how, how, name, name, uid, pwd,
1789 		    buffer, bufsize, errnop);
1790 		if (rv != NS_SUCCESS)
1791 			st->compat = COMPAT_MODE_OFF;
1792 		break;
1793 	case COMPAT_MODE_NETGROUP:
1794 		/* XXX getnetgrent is not thread-safe. */
1795 		do {
1796 			rv = getnetgrent(&host, &user, &domain);
1797 			if (rv == 0) {
1798 				endnetgrent();
1799 				st->compat = COMPAT_MODE_OFF;
1800 				rv = NS_NOTFOUND;
1801 				continue;
1802 			} else if (user == NULL || user[0] == '\0')
1803 				continue;
1804 			rv = compat_redispatch(st, how, nss_lt_name, name,
1805 			    user, uid, pwd, buffer, bufsize, errnop);
1806 		} while (st->compat == COMPAT_MODE_NETGROUP &&
1807 		    !(rv & NS_TERMINATE));
1808 		break;
1809 	case COMPAT_MODE_NAME:
1810 		rv = compat_redispatch(st, how, nss_lt_name, name, st->name,
1811 		    uid, pwd, buffer, bufsize, errnop);
1812 		free(st->name);
1813 		st->name = NULL;
1814 		st->compat = COMPAT_MODE_OFF;
1815 		break;
1816 	default:
1817 		break;
1818 	}
1819 	if (rv & NS_TERMINATE) {
1820 		from_compat = 1;
1821 		goto fin;
1822 	}
1823 	key.data = keybuf;
1824 	rv = NS_NOTFOUND;
1825 	while (st->keynum >= 0) {
1826 		st->keynum++;
1827 		if (st->version < _PWD_CURRENT_VERSION) {
1828 			memcpy(&keybuf[1], &st->keynum, sizeof(st->keynum));
1829 			key.size = sizeof(st->keynum) + 1;
1830 		} else {
1831 			store = htonl(st->keynum);
1832 			memcpy(&keybuf[1], &store, sizeof(store));
1833 			key.size = sizeof(store) + 1;
1834 		}
1835 		keybuf[0] = _PW_VERSIONED(_PW_KEYBYNUM, st->version);
1836 		rv = st->db->get(st->db, &key, &entry, 0);
1837 		if (rv < 0 || rv > 1) { /* should never return > 1 */
1838 			*errnop = errno;
1839 			rv = NS_UNAVAIL;
1840 			goto fin;
1841 		} else if (rv == 1) {
1842 			st->keynum = -1;
1843 			rv = NS_NOTFOUND;
1844 			goto fin;
1845 		}
1846 		pw_name = (char *)entry.data;
1847 		switch (pw_name[0]) {
1848 		case '+':
1849 			switch (pw_name[1]) {
1850 			case '\0':
1851 				st->compat = COMPAT_MODE_ALL;
1852 				break;
1853 			case '@':
1854 				setnetgrent(&pw_name[2]);
1855 				st->compat = COMPAT_MODE_NETGROUP;
1856 				break;
1857 			default:
1858 				st->name = strdup(&pw_name[1]);
1859 				if (st->name == NULL) {
1860 					syslog(LOG_ERR,
1861 					 "getpwent memory allocation failure");
1862 					*errnop = ENOMEM;
1863 					rv = NS_UNAVAIL;
1864 					break;
1865 				}
1866 				st->compat = COMPAT_MODE_NAME;
1867 			}
1868 			if (entry.size > bufsize) {
1869 				*errnop = ERANGE;
1870 				rv = NS_RETURN;
1871 				goto fin;
1872 			}
1873 			memcpy(buffer, entry.data, entry.size);
1874 			rv = pwdb_versions[st->version].parse(buffer,
1875 			    entry.size, pwd, errnop);
1876 			if (rv != NS_SUCCESS)
1877 				;
1878 			else if (compat_set_template(pwd, &st->template) < 0) {
1879 				*errnop = ENOMEM;
1880 				rv = NS_UNAVAIL;
1881 				goto fin;
1882 			}
1883 			goto docompat;
1884 		case '-':
1885 			switch (pw_name[1]) {
1886 			case '\0':
1887 				/* XXX Maybe syslog warning */
1888 				continue;
1889 			case '@':
1890 				setnetgrent(&pw_name[2]);
1891 				while (getnetgrent(&host, &user, &domain) !=
1892 				    0) {
1893 					if (user != NULL && user[0] != '\0')
1894 						compat_exclude(user,
1895 						    &st->exclude);
1896 				}
1897 				endnetgrent();
1898 				continue;
1899 			default:
1900 				compat_exclude(&pw_name[1], &st->exclude);
1901 				continue;
1902 			}
1903 			break;
1904 		default:
1905 			break;
1906 		}
1907 		if (compat_is_excluded((char *)entry.data, st->exclude))
1908 			continue;
1909 		rv = pwdb_versions[st->version].match(entry.data, entry.size,
1910 		    how, name, uid);
1911 		if (rv == NS_RETURN)
1912 			break;
1913 		else if (rv != NS_SUCCESS)
1914 			continue;
1915 		if (entry.size > bufsize) {
1916 			*errnop = ERANGE;
1917 			rv = NS_RETURN;
1918 			break;
1919 		}
1920 		memcpy(buffer, entry.data, entry.size);
1921 		rv = pwdb_versions[st->version].parse(buffer, entry.size, pwd,
1922 		    errnop);
1923 		if (rv & NS_TERMINATE)
1924 			break;
1925 	}
1926 fin:
1927 	if (st->db != NULL && !stayopen) {
1928 		(void)st->db->close(st->db);
1929 		st->db = NULL;
1930 	}
1931 	if (rv == NS_SUCCESS) {
1932 		if (!from_compat) {
1933 			pwd->pw_fields &= ~_PWF_SOURCE;
1934 			pwd->pw_fields |= _PWF_FILES;
1935 		}
1936 		if (retval != NULL)
1937 			*(struct passwd **)retval = pwd;
1938 	}
1939 	return (rv);
1940 }
1941 
1942 
1943 /*
1944  * common passwd line matching and parsing
1945  */
1946 int
1947 __pw_match_entry(const char *entry, size_t entrysize, enum nss_lookup_type how,
1948     const char *name, uid_t uid)
1949 {
1950 	const char	*p, *eom;
1951 	char		*q;
1952 	size_t		 len;
1953 	unsigned long	 m;
1954 
1955 	eom = entry + entrysize;
1956 	for (p = entry; p < eom; p++)
1957 		if (*p == ':')
1958 			break;
1959 	if (*p != ':')
1960 		return (NS_NOTFOUND);
1961 	if (how == nss_lt_all)
1962 		return (NS_SUCCESS);
1963 	if (how == nss_lt_name) {
1964 		len = strlen(name);
1965 		if (len == (p - entry) && memcmp(name, entry, len) == 0)
1966 			return (NS_SUCCESS);
1967 		else
1968 			return (NS_NOTFOUND);
1969 	}
1970 	for (p++; p < eom; p++)
1971 		if (*p == ':')
1972 			break;
1973 	if (*p != ':')
1974 		return (NS_NOTFOUND);
1975 	m = strtoul(++p, &q, 10);
1976 	if (q[0] != ':' || (uid_t)m != uid)
1977 		return (NS_NOTFOUND);
1978 	else
1979 		return (NS_SUCCESS);
1980 }
1981 
1982 
1983 /* XXX buffer must be NUL-terminated.  errnop is not set correctly. */
1984 int
1985 __pw_parse_entry(char *buffer, size_t bufsize __unused, struct passwd *pwd,
1986     int master, int *errnop __unused)
1987 {
1988 
1989 	if (__pw_scan(buffer, pwd, master ? _PWSCAN_MASTER : 0) == 0)
1990 		return (NS_NOTFOUND);
1991 	else
1992 		return (NS_SUCCESS);
1993 }
1994