xref: /netbsd-src/lib/libc/gen/getpwent.c (revision 2a399c6883d870daece976daec6ffa7bb7f934ce)
1 /*	$NetBSD: getpwent.c,v 1.23 1997/07/21 14:07:13 jtc Exp $	*/
2 
3 /*
4  * Copyright (c) 1988, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * Portions Copyright (c) 1994, 1995, Jason Downs.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #include <sys/cdefs.h>
38 #if defined(LIBC_SCCS) && !defined(lint)
39 #if 0
40 static char sccsid[] = "@(#)getpwent.c	8.1 (Berkeley) 6/4/93";
41 #else
42 __RCSID("$NetBSD: getpwent.c,v 1.23 1997/07/21 14:07:13 jtc Exp $");
43 #endif
44 #endif /* LIBC_SCCS and not lint */
45 
46 #include "namespace.h"
47 #include <sys/param.h>
48 #include <fcntl.h>
49 #include <db.h>
50 #include <syslog.h>
51 #include <pwd.h>
52 #include <utmp.h>
53 #include <errno.h>
54 #include <unistd.h>
55 #include <stdlib.h>
56 #include <string.h>
57 #include <limits.h>
58 #include <netgroup.h>
59 #ifdef YP
60 #include <machine/param.h>
61 #include <stdio.h>
62 #include <rpc/rpc.h>
63 #include <rpcsvc/yp_prot.h>
64 #include <rpcsvc/ypclnt.h>
65 #endif
66 
67 #ifdef __weak_alias
68 __weak_alias(endpwent,_endpwent);
69 __weak_alias(getpwent,_getpwent);
70 __weak_alias(getpwnam,_getpwnam);
71 __weak_alias(getpwuid,_getpwuid);
72 __weak_alias(setpassent,_setpassent);
73 __weak_alias(setpwent,_setpwent);
74 #endif
75 
76 static struct passwd _pw_passwd;	/* password structure */
77 static DB *_pw_db;			/* password database */
78 static int _pw_keynum;			/* key counter */
79 static int _pw_stayopen;		/* keep fd's open */
80 static int _pw_flags;			/* password flags */
81 static int __hashpw __P((DBT *));
82 static int __initdb __P((void));
83 
84 const char __yp_token[] = "__YP!";	/* Let pwd_mkdb pull this in. */
85 
86 #ifdef YP
87 enum _ypmode { YPMODE_NONE, YPMODE_FULL, YPMODE_USER, YPMODE_NETGRP };
88 static enum _ypmode __ypmode;
89 
90 static char     *__ypcurrent, *__ypdomain;
91 static int      __ypcurrentlen;
92 static struct passwd *__ypproto = (struct passwd *)NULL;
93 static int	__ypflags;
94 static char	line[1024];
95 static long	prbuf[1024 / sizeof(long)];
96 static DB *__ypexclude = (DB *)NULL;
97 
98 static int __has_yppw __P((void));
99 static int __ypexclude_add __P((const char *));
100 static int __ypexclude_is __P((const char *));
101 static void __ypproto_set __P((void));
102 static int __ypparse __P((struct passwd *, char *));
103 
104 static int
105 __ypexclude_add(name)
106 const char *name;
107 {
108 	DBT key, data;
109 
110 	/* initialize the exclusion table if needed. */
111 	if(__ypexclude == (DB *)NULL) {
112 		__ypexclude = dbopen(NULL, O_RDWR, 600, DB_HASH, NULL);
113 		if(__ypexclude == (DB *)NULL)
114 			return(1);
115 	}
116 
117 	/* set up the key */
118 	key.data = (char *)name;
119 	key.size = strlen(name);
120 
121 	/* data is nothing. */
122 	data.data = NULL;
123 	data.size = 0;
124 
125 	/* store it */
126 	if((__ypexclude->put)(__ypexclude, &key, &data, 0) == -1)
127 		return(1);
128 
129 	return(0);
130 }
131 
132 static int
133 __ypexclude_is(name)
134 const char *name;
135 {
136 	DBT key, data;
137 
138 	if(__ypexclude == (DB *)NULL)
139 		return(0);	/* nothing excluded */
140 
141 	/* set up the key */
142 	key.data = (char *)name;
143 	key.size = strlen(name);
144 
145 	if((__ypexclude->get)(__ypexclude, &key, &data, 0) == 0)
146 		return(1);	/* excluded */
147 
148 	return(0);
149 }
150 
151 static void
152 __ypproto_set()
153 {
154 	char *ptr;
155 	struct passwd *pw = &_pw_passwd;
156 
157 	/* make this the new prototype */
158 	ptr = (char *)prbuf;
159 
160 	/* first allocate the struct. */
161 	__ypproto = (struct passwd *)ptr;
162 	ptr += sizeof(struct passwd);
163 
164 	/* name */
165 	if(pw->pw_name && (pw->pw_name)[0]) {
166 		ptr = (char *)ALIGN(ptr);
167 		bcopy(pw->pw_name, ptr, strlen(pw->pw_name) + 1);
168 		__ypproto->pw_name = ptr;
169 		ptr += (strlen(pw->pw_name) + 1);
170 	} else
171 		__ypproto->pw_name = (char *)NULL;
172 
173 	/* password */
174 	if(pw->pw_passwd && (pw->pw_passwd)[0]) {
175 		ptr = (char *)ALIGN(ptr);
176 		bcopy(pw->pw_passwd, ptr, strlen(pw->pw_passwd) + 1);
177 		__ypproto->pw_passwd = ptr;
178 		ptr += (strlen(pw->pw_passwd) + 1);
179 	} else
180 		__ypproto->pw_passwd = (char *)NULL;
181 
182 	/* uid */
183 	__ypproto->pw_uid = pw->pw_uid;
184 
185 	/* gid */
186 	__ypproto->pw_gid = pw->pw_gid;
187 
188 	/* change (ignored anyway) */
189 	__ypproto->pw_change = pw->pw_change;
190 
191 	/* class (ignored anyway) */
192 	__ypproto->pw_class = "";
193 
194 	/* gecos */
195 	if(pw->pw_gecos && (pw->pw_gecos)[0]) {
196 		ptr = (char *)ALIGN(ptr);
197 		bcopy(pw->pw_gecos, ptr, strlen(pw->pw_gecos) + 1);
198 		__ypproto->pw_gecos = ptr;
199 		ptr += (strlen(pw->pw_gecos) + 1);
200 	} else
201 		__ypproto->pw_gecos = (char *)NULL;
202 
203 	/* dir */
204 	if(pw->pw_dir && (pw->pw_dir)[0]) {
205 		ptr = (char *)ALIGN(ptr);
206 		bcopy(pw->pw_dir, ptr, strlen(pw->pw_dir) + 1);
207 		__ypproto->pw_dir = ptr;
208 		ptr += (strlen(pw->pw_dir) + 1);
209 	} else
210 		__ypproto->pw_dir = (char *)NULL;
211 
212 	/* shell */
213 	if(pw->pw_shell && (pw->pw_shell)[0]) {
214 		ptr = (char *)ALIGN(ptr);
215 		bcopy(pw->pw_shell, ptr, strlen(pw->pw_shell) + 1);
216 		__ypproto->pw_shell = ptr;
217 		ptr += (strlen(pw->pw_shell) + 1);
218 	} else
219 		__ypproto->pw_shell = (char *)NULL;
220 
221 	/* expire (ignored anyway) */
222 	__ypproto->pw_expire = pw->pw_expire;
223 
224 	/* flags */
225 	__ypflags = _pw_flags;
226 }
227 
228 static int
229 __ypparse(pw, s)
230 struct passwd *pw;
231 char *s;
232 {
233 	char *bp, *cp, *ep;
234 	unsigned long id;
235 
236 	/* since this is currently using strsep(), parse it first */
237 	bp = s;
238 	pw->pw_name = strsep(&bp, ":\n");
239 	pw->pw_passwd = strsep(&bp, ":\n");
240 	if (!(cp = strsep(&bp, ":\n")))
241 		return 1;
242 	id = strtoul(cp, &ep, 10);
243 	if (id > UID_MAX || *ep != '\0')
244 		return 1;
245 	pw->pw_uid = (uid_t)id;
246 	if (!(cp = strsep(&bp, ":\n")))
247 		return 1;
248 	id = strtoul(cp, &ep, 10);
249 	if (id > GID_MAX || *ep != '\0')
250 		return 1;
251 	pw->pw_gid = (gid_t)id;
252 	pw->pw_change = 0;
253 	pw->pw_class = "";
254 	pw->pw_gecos = strsep(&bp, ":\n");
255 	pw->pw_dir = strsep(&bp, ":\n");
256 	pw->pw_shell = strsep(&bp, ":\n");
257 	pw->pw_expire = 0;
258 
259 	/* now let the prototype override, if set. */
260 	if(__ypproto != (struct passwd *)NULL) {
261 #ifdef YP_OVERRIDE_PASSWD
262 		if(__ypproto->pw_passwd != (char *)NULL)
263 			pw->pw_passwd = __ypproto->pw_passwd;
264 #endif
265 		if(!(__ypflags & _PASSWORD_NOUID))
266 			pw->pw_uid = __ypproto->pw_uid;
267 		if(!(__ypflags & _PASSWORD_NOGID))
268 			pw->pw_gid = __ypproto->pw_gid;
269 		if(__ypproto->pw_gecos != (char *)NULL)
270 			pw->pw_gecos = __ypproto->pw_gecos;
271 		if(__ypproto->pw_dir != (char *)NULL)
272 			pw->pw_dir = __ypproto->pw_dir;
273 		if(__ypproto->pw_shell != (char *)NULL)
274 			pw->pw_shell = __ypproto->pw_shell;
275 	}
276 	return 0;
277 }
278 #endif
279 
280 struct passwd *
281 getpwent()
282 {
283 	DBT key;
284 	char bf[sizeof(_pw_keynum) + 1];
285 #ifdef YP
286 	static char *name = (char *)NULL;
287 	const char *user, *host, *dom;
288 	int has_yppw;
289 #endif
290 
291 	if (!_pw_db && !__initdb())
292 		return((struct passwd *)NULL);
293 
294 #ifdef YP
295 	has_yppw = __has_yppw();
296 
297 again:
298 	if(has_yppw && (__ypmode != YPMODE_NONE)) {
299 		char *key, *data;
300 		int keylen, datalen;
301 		int r, s;
302 
303 		if(!__ypdomain) {
304 			if( _yp_check(&__ypdomain) == 0) {
305 				__ypmode = YPMODE_NONE;
306 				goto again;
307 			}
308 		}
309 		switch(__ypmode) {
310 		case YPMODE_FULL:
311 			data = NULL;
312 			if(__ypcurrent) {
313 				key = NULL;
314 				r = yp_next(__ypdomain, "passwd.byname",
315 					__ypcurrent, __ypcurrentlen,
316 					&key, &keylen, &data, &datalen);
317 				free(__ypcurrent);
318 				if(r != 0) {
319 					__ypcurrent = NULL;
320 					if (key)
321 						free(key);
322 				}
323 				else {
324 					__ypcurrent = key;
325 					__ypcurrentlen = keylen;
326 				}
327 			} else {
328 				r = yp_first(__ypdomain, "passwd.byname",
329 					&__ypcurrent, &__ypcurrentlen,
330 					&data, &datalen);
331 			}
332 			if(r != 0) {
333 				__ypmode = YPMODE_NONE;
334 				if(data)
335 					free(data);
336 				data = NULL;
337 				goto again;
338 			}
339 			bcopy(data, line, datalen);
340 			free(data);
341 			data = NULL;
342 			break;
343 		case YPMODE_NETGRP:
344 			s = getnetgrent(&host, &user, &dom);
345 			if(s == 0) {	/* end of group */
346 				endnetgrent();
347 				__ypmode = YPMODE_NONE;
348 				goto again;
349 			}
350 			if(user && *user) {
351 				data = NULL;
352 				r = yp_match(__ypdomain, "passwd.byname",
353 					user, strlen(user),
354 					&data, &datalen);
355 			} else
356 				goto again;
357 			if(r != 0) {
358 				/*
359 				 * if the netgroup is invalid, keep looking
360 				 * as there may be valid users later on.
361 				 */
362 				if(data)
363 					free(data);
364 				goto again;
365 			}
366 			bcopy(data, line, datalen);
367 			free(data);
368 			data = NULL;
369 			break;
370 		case YPMODE_USER:
371 			if(name != (char *)NULL) {
372 				data = NULL;
373 				r = yp_match(__ypdomain, "passwd.byname",
374 					name, strlen(name),
375 					&data, &datalen);
376 				__ypmode = YPMODE_NONE;
377 				free(name);
378 				name = NULL;
379 				if(r != 0) {
380 					if(data)
381 						free(data);
382 					goto again;
383 				}
384 				bcopy(data, line, datalen);
385 				free(data);
386 				data = (char *)NULL;
387 			} else {		/* XXX */
388 				__ypmode = YPMODE_NONE;
389 				goto again;
390 			}
391 			break;
392 		case YPMODE_NONE:
393 			abort();	/* cannot happen */
394 			break;
395 		}
396 
397 		line[datalen] = '\0';
398 		if (__ypparse(&_pw_passwd, line))
399 			goto again;
400 		return &_pw_passwd;
401 	}
402 #endif
403 
404 	++_pw_keynum;
405 	bf[0] = _PW_KEYBYNUM;
406 	bcopy((char *)&_pw_keynum, bf + 1, sizeof(_pw_keynum));
407 	key.data = (u_char *)bf;
408 	key.size = sizeof(_pw_keynum) + 1;
409 	if(__hashpw(&key)) {
410 #ifdef YP
411 		/* if we don't have YP at all, don't bother. */
412 		if(has_yppw) {
413 			if(_pw_passwd.pw_name[0] == '+') {
414 				/* set the mode */
415 				switch(_pw_passwd.pw_name[1]) {
416 				case '\0':
417 					__ypmode = YPMODE_FULL;
418 					break;
419 				case '@':
420 					__ypmode = YPMODE_NETGRP;
421 					setnetgrent(_pw_passwd.pw_name + 2);
422 					break;
423 				default:
424 					__ypmode = YPMODE_USER;
425 					name = strdup(_pw_passwd.pw_name + 1);
426 					break;
427 				}
428 
429 				/* save the prototype */
430 				__ypproto_set();
431 				goto again;
432 			} else if(_pw_passwd.pw_name[0] == '-') {
433 				/* an attempted exclusion */
434 				switch(_pw_passwd.pw_name[1]) {
435 				case '\0':
436 					break;
437 				case '@':
438 					setnetgrent(_pw_passwd.pw_name + 2);
439 					while(getnetgrent(&host, &user, &dom)) {
440 						if(user && *user)
441 							__ypexclude_add(user);
442 					}
443 					endnetgrent();
444 					break;
445 				default:
446 					__ypexclude_add(_pw_passwd.pw_name + 1);
447 					break;
448 				}
449 				goto again;
450 			}
451 		}
452 #endif
453 		return &_pw_passwd;
454 	}
455 	return (struct passwd *)NULL;
456 }
457 
458 #ifdef YP
459 
460 /*
461  * See if the YP token is in the database.  Only works if pwd_mkdb knows
462  * about the token.
463  */
464 static int
465 __has_yppw()
466 {
467 	DBT key, data;
468 	DBT pkey, pdata;
469 	char bf[MAXLOGNAME];
470 
471 	key.data = (u_char *)__yp_token;
472 	key.size = strlen(__yp_token);
473 
474 	/* Pre-token database support. */
475 	bf[0] = _PW_KEYBYNAME;
476 	bf[1] = '+';
477 	pkey.data = (u_char *)bf;
478 	pkey.size = 2;
479 
480 	if ((_pw_db->get)(_pw_db, &key, &data, 0)
481 	    && (_pw_db->get)(_pw_db, &pkey, &pdata, 0))
482 		return(0);	/* No YP. */
483 	return(1);
484 }
485 #endif
486 
487 struct passwd *
488 getpwnam(name)
489 	const char *name;
490 {
491 	DBT key;
492 	int len, rval;
493 	char bf[MAXLOGNAME + 1];
494 
495 	if (!_pw_db && !__initdb())
496 		return((struct passwd *)NULL);
497 
498 #ifdef YP
499 	/*
500 	 * If YP is active, we must sequence through the passwd file
501 	 * in sequence.
502 	 */
503 	if (__has_yppw()) {
504 		int r;
505 		int s = -1;
506 		const char *host, *user, *dom;
507 
508 		for(_pw_keynum=1; _pw_keynum; _pw_keynum++) {
509 			bf[0] = _PW_KEYBYNUM;
510 			bcopy((char *)&_pw_keynum, bf + 1, sizeof(_pw_keynum));
511 			key.data = (u_char *)bf;
512 			key.size = sizeof(_pw_keynum) + 1;
513 			if(__hashpw(&key) == 0)
514 				break;
515 			switch(_pw_passwd.pw_name[0]) {
516 			case '+':
517 				if(!__ypdomain) {
518 					if(_yp_check(&__ypdomain) == 0) {
519 						continue;
520 					}
521 				}
522 				/* save the prototype */
523 				__ypproto_set();
524 
525 				switch(_pw_passwd.pw_name[1]) {
526 				case '\0':
527 					if(__ypcurrent) {
528 						free(__ypcurrent);
529 						__ypcurrent = NULL;
530 					}
531 					r = yp_match(__ypdomain,
532 						"passwd.byname",
533 						name, strlen(name),
534 						&__ypcurrent, &__ypcurrentlen);
535 					if(r != 0) {
536 						if(__ypcurrent)
537 							free(__ypcurrent);
538 						__ypcurrent = NULL;
539 						continue;
540 					}
541 					break;
542 				case '@':
543 pwnam_netgrp:
544 					if(__ypcurrent) {
545 						free(__ypcurrent);
546 						__ypcurrent = NULL;
547 					}
548 					if(s == -1)	/* first time */
549 						setnetgrent(_pw_passwd.pw_name + 2);
550 					s = getnetgrent(&host, &user, &dom);
551 					if(s == 0) {	/* end of group */
552 						endnetgrent();
553 						s = -1;
554 						continue;
555 					} else {
556 						if(user && *user) {
557 							r = yp_match(__ypdomain,
558 							    "passwd.byname",
559 							    user, strlen(user),
560 							    &__ypcurrent,
561 							    &__ypcurrentlen);
562 						} else
563 							goto pwnam_netgrp;
564 						if(r != 0) {
565 							if(__ypcurrent)
566 							    free(__ypcurrent);
567 							__ypcurrent = NULL;
568 							/*
569 							 * just because this
570 							 * user is bad, doesn't
571 							 * mean they all are.
572 							 */
573 							goto pwnam_netgrp;
574 						}
575 					}
576 					break;
577 				default:
578 					if(__ypcurrent) {
579 						free(__ypcurrent);
580 						__ypcurrent = NULL;
581 					}
582 					user = _pw_passwd.pw_name + 1;
583 					r = yp_match(__ypdomain,
584 						"passwd.byname",
585 						user, strlen(user),
586 						&__ypcurrent,
587 						&__ypcurrentlen);
588 					if(r != 0) {
589 						if(__ypcurrent)
590 							free(__ypcurrent);
591 						__ypcurrent = NULL;
592 						continue;
593 					}
594 					break;
595 				}
596 				bcopy(__ypcurrent, line, __ypcurrentlen);
597 				line[__ypcurrentlen] = '\0';
598 				if(__ypparse(&_pw_passwd, line)
599 				   || __ypexclude_is(_pw_passwd.pw_name)) {
600 					if(s == 1)	/* inside netgrp */
601 						goto pwnam_netgrp;
602 					continue;
603 				}
604 				break;
605 			case '-':
606 				/* attempted exclusion */
607 				switch(_pw_passwd.pw_name[1]) {
608 				case '\0':
609 					break;
610 				case '@':
611 					setnetgrent(_pw_passwd.pw_name + 2);
612 					while(getnetgrent(&host, &user, &dom)) {
613 						if(user && *user)
614 							__ypexclude_add(user);
615 					}
616 					endnetgrent();
617 					break;
618 				default:
619 					__ypexclude_add(_pw_passwd.pw_name + 1);
620 					break;
621 				}
622 				break;
623 
624 				continue;
625 			}
626 			if(strcmp(_pw_passwd.pw_name, name) == 0) {
627 				if (!_pw_stayopen) {
628 					(void)(_pw_db->close)(_pw_db);
629 					_pw_db = (DB *)NULL;
630 				}
631 				if(__ypexclude != (DB *)NULL) {
632 					(void)(__ypexclude->close)(__ypexclude);
633 					__ypexclude = (DB *)NULL;
634 				}
635 				__ypproto = (struct passwd *)NULL;
636 				return &_pw_passwd;
637 			}
638 			if(s == 1)	/* inside netgrp */
639 				goto pwnam_netgrp;
640 			continue;
641 		}
642 		if (!_pw_stayopen) {
643 			(void)(_pw_db->close)(_pw_db);
644 			_pw_db = (DB *)NULL;
645 		}
646 		if(__ypexclude != (DB *)NULL) {
647 			(void)(__ypexclude->close)(__ypexclude);
648 			__ypexclude = (DB *)NULL;
649 		}
650 		__ypproto = (struct passwd *)NULL;
651 		return (struct passwd *)NULL;
652 	}
653 #endif /* YP */
654 
655 	bf[0] = _PW_KEYBYNAME;
656 	len = strlen(name);
657 	len = MIN(len, MAXLOGNAME);
658 	bcopy(name, bf + 1, len);
659 	key.data = (u_char *)bf;
660 	key.size = len + 1;
661 	rval = __hashpw(&key);
662 
663 	if (!_pw_stayopen) {
664 		(void)(_pw_db->close)(_pw_db);
665 		_pw_db = (DB *)NULL;
666 	}
667 	return(rval ? &_pw_passwd : (struct passwd *)NULL);
668 }
669 
670 struct passwd *
671 #ifdef __STDC__
672 getpwuid(uid_t uid)
673 #else
674 getpwuid(uid)
675 	uid_t uid;
676 #endif
677 {
678 	DBT key;
679 	char bf[sizeof(_pw_keynum) + 1];
680 	uid_t keyuid;
681 	int rval;
682 
683 	if (!_pw_db && !__initdb())
684 		return((struct passwd *)NULL);
685 
686 #ifdef YP
687 	/*
688 	 * If YP is active, we must sequence through the passwd file
689 	 * in sequence.
690 	 */
691 	if (__has_yppw()) {
692 		char uidbuf[20];
693 		int r;
694 		int s = -1;
695 		const char *host, *user, *dom;
696 
697 		snprintf(uidbuf, sizeof(uidbuf), "%u", uid);
698 		for(_pw_keynum=1; _pw_keynum; _pw_keynum++) {
699 			bf[0] = _PW_KEYBYNUM;
700 			bcopy((char *)&_pw_keynum, bf + 1, sizeof(_pw_keynum));
701 			key.data = (u_char *)bf;
702 			key.size = sizeof(_pw_keynum) + 1;
703 			if(__hashpw(&key) == 0)
704 				break;
705 			switch(_pw_passwd.pw_name[0]) {
706 			case '+':
707 				if(!__ypdomain) {
708 					if(_yp_check(&__ypdomain) == 0) {
709 						continue;
710 					}
711 				}
712 				/* save the prototype */
713 				__ypproto_set();
714 
715 				switch(_pw_passwd.pw_name[1]) {
716 				case '\0':
717 					if(__ypcurrent) {
718 						free(__ypcurrent);
719 						__ypcurrent = NULL;
720 					}
721 					r = yp_match(__ypdomain, "passwd.byuid",
722 						uidbuf, strlen(uidbuf),
723 						&__ypcurrent, &__ypcurrentlen);
724 					if(r != 0) {
725 						if(__ypcurrent)
726 							free(__ypcurrent);
727 						__ypcurrent = NULL;
728 						continue;
729 					}
730 					break;
731 				case '@':
732 pwuid_netgrp:
733 					if(__ypcurrent) {
734 						free(__ypcurrent);
735 						__ypcurrent = NULL;
736 					}
737 					if(s == -1)	/* first time */
738 						setnetgrent(_pw_passwd.pw_name + 2);
739 					s = getnetgrent(&host, &user, &dom);
740 					if(s == 0) {	/* end of group */
741 						endnetgrent();
742 						s = -1;
743 						continue;
744 					} else {
745 						if(user && *user) {
746 							r = yp_match(__ypdomain,
747 							    "passwd.byname",
748 							    user, strlen(user),
749 							    &__ypcurrent,
750 							    &__ypcurrentlen);
751 						} else
752 							goto pwuid_netgrp;
753 						if(r != 0) {
754 							if(__ypcurrent)
755 							    free(__ypcurrent);
756 							__ypcurrent = NULL;
757 							/*
758                                                          * just because this
759 							 * user is bad, doesn't
760 							 * mean they all are.
761 							 */
762 							goto pwuid_netgrp;
763 						}
764 					}
765 					break;
766 				default:
767 					if(__ypcurrent) {
768 						free(__ypcurrent);
769 						__ypcurrent = NULL;
770 					}
771 					user = _pw_passwd.pw_name + 1;
772 					r = yp_match(__ypdomain,
773 						"passwd.byname",
774 						user, strlen(user),
775 						&__ypcurrent,
776 						&__ypcurrentlen);
777 					if(r != 0) {
778 						if(__ypcurrent)
779 							free(__ypcurrent);
780 						__ypcurrent = NULL;
781 						continue;
782 					}
783 					break;
784 				}
785 				bcopy(__ypcurrent, line, __ypcurrentlen);
786 				line[__ypcurrentlen] = '\0';
787 				if(__ypparse(&_pw_passwd, line)
788 				   || __ypexclude_is(_pw_passwd.pw_name)) {
789 					if(s == 1)	/* inside netgroup */
790 						goto pwuid_netgrp;
791 					continue;
792 				}
793 				break;
794 			case '-':
795 				/* attempted exclusion */
796 				switch(_pw_passwd.pw_name[1]) {
797 				case '\0':
798 					break;
799 				case '@':
800 					setnetgrent(_pw_passwd.pw_name + 2);
801 					while(getnetgrent(&host, &user, &dom)) {
802 						if(user && *user)
803 							__ypexclude_add(user);
804 					}
805 					endnetgrent();
806 					break;
807 				default:
808 					__ypexclude_add(_pw_passwd.pw_name + 1);
809 					break;
810 				}
811 				break;
812 
813 				continue;
814 			}
815 			if( _pw_passwd.pw_uid == uid) {
816 				if (!_pw_stayopen) {
817 					(void)(_pw_db->close)(_pw_db);
818 					_pw_db = (DB *)NULL;
819 				}
820 				if (__ypexclude != (DB *)NULL) {
821 					(void)(__ypexclude->close)(__ypexclude);
822 					__ypexclude = (DB *)NULL;
823 				}
824 				__ypproto = NULL;
825 				return &_pw_passwd;
826 			}
827 			if(s == 1)	/* inside netgroup */
828 				goto pwuid_netgrp;
829 			continue;
830 		}
831 		if (!_pw_stayopen) {
832 			(void)(_pw_db->close)(_pw_db);
833 			_pw_db = (DB *)NULL;
834 		}
835 		if(__ypexclude != (DB *)NULL) {
836 			(void)(__ypexclude->close)(__ypexclude);
837 			__ypexclude = (DB *)NULL;
838 		}
839 		__ypproto = (struct passwd *)NULL;
840 		return (struct passwd *)NULL;
841 	}
842 #endif /* YP */
843 
844 	bf[0] = _PW_KEYBYUID;
845 	keyuid = uid;
846 	bcopy(&keyuid, bf + 1, sizeof(keyuid));
847 	key.data = (u_char *)bf;
848 	key.size = sizeof(keyuid) + 1;
849 	rval = __hashpw(&key);
850 
851 	if (!_pw_stayopen) {
852 		(void)(_pw_db->close)(_pw_db);
853 		_pw_db = (DB *)NULL;
854 	}
855 	return(rval ? &_pw_passwd : (struct passwd *)NULL);
856 }
857 
858 int
859 setpassent(stayopen)
860 	int stayopen;
861 {
862 	_pw_keynum = 0;
863 	_pw_stayopen = stayopen;
864 #ifdef YP
865 	__ypmode = YPMODE_NONE;
866 	if(__ypcurrent)
867 		free(__ypcurrent);
868 	__ypcurrent = NULL;
869 	if(__ypexclude != (DB *)NULL) {
870 		(void)(__ypexclude->close)(__ypexclude);
871 		__ypexclude = (DB *)NULL;
872 	}
873 	__ypproto = (struct passwd *)NULL;
874 #endif
875 	return(1);
876 }
877 
878 void
879 setpwent()
880 {
881 	(void) setpassent(0);
882 }
883 
884 void
885 endpwent()
886 {
887 	_pw_keynum = 0;
888 	if (_pw_db) {
889 		(void)(_pw_db->close)(_pw_db);
890 		_pw_db = (DB *)NULL;
891 	}
892 #ifdef YP
893 	__ypmode = YPMODE_NONE;
894 	if(__ypcurrent)
895 		free(__ypcurrent);
896 	__ypcurrent = NULL;
897 	if(__ypexclude != (DB *)NULL) {
898 		(void)(__ypexclude->close)(__ypexclude);
899 		__ypexclude = (DB *)NULL;
900 	}
901 	__ypproto = (struct passwd *)NULL;
902 #endif
903 }
904 
905 static int
906 __initdb()
907 {
908 	static int warned;
909 	char *p;
910 
911 #ifdef YP
912 	__ypmode = YPMODE_NONE;
913 #endif
914 	p = (geteuid()) ? _PATH_MP_DB : _PATH_SMP_DB;
915 	_pw_db = dbopen(p, O_RDONLY, 0, DB_HASH, NULL);
916 	if (_pw_db)
917 		return(1);
918 	if (!warned)
919 		syslog(LOG_ERR, "%s: %m", p);
920 	warned = 1;
921 	return(0);
922 }
923 
924 static int
925 __hashpw(key)
926 	DBT *key;
927 {
928 	char *p, *t;
929 	static u_int max;
930 	static char *line;
931 	DBT data;
932 
933 	if ((_pw_db->get)(_pw_db, key, &data, 0))
934 		return(0);
935 	p = (char *)data.data;
936 	if (data.size > max && !(line = realloc(line, (max += 1024))))
937 		return(0);
938 
939 	t = line;
940 #define	EXPAND(e)	e = t; while ((*t++ = *p++));
941 	EXPAND(_pw_passwd.pw_name);
942 	EXPAND(_pw_passwd.pw_passwd);
943 	bcopy(p, (char *)&_pw_passwd.pw_uid, sizeof(int));
944 	p += sizeof(int);
945 	bcopy(p, (char *)&_pw_passwd.pw_gid, sizeof(int));
946 	p += sizeof(int);
947 	bcopy(p, (char *)&_pw_passwd.pw_change, sizeof(time_t));
948 	p += sizeof(time_t);
949 	EXPAND(_pw_passwd.pw_class);
950 	EXPAND(_pw_passwd.pw_gecos);
951 	EXPAND(_pw_passwd.pw_dir);
952 	EXPAND(_pw_passwd.pw_shell);
953 	bcopy(p, (char *)&_pw_passwd.pw_expire, sizeof(time_t));
954 	p += sizeof(time_t);
955 
956 	/* See if there's any data left.  If so, read in flags. */
957 	if (data.size > (p - (char *)data.data)) {
958 		bcopy(p, (char *)&_pw_flags, sizeof(int));
959 		p += sizeof(int);
960 	} else
961 		_pw_flags = _PASSWORD_NOUID|_PASSWORD_NOGID;	/* default */
962 
963 	return(1);
964 }
965