xref: /netbsd-src/distrib/utils/libhack/getpwent.c (revision d710132b4b8ce7f7cccaaf660cb16aa16b4077a0)
1 /*	$NetBSD: getpwent.c,v 1.6 2002/05/13 06:38:14 elric Exp $	*/
2 
3 /*
4  * Copyright (c) 1987, 1988, 1989, 1993, 1994, 1995
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 /*
37  * Copied from:  lib/libc/gen/getpwent.c
38  *	NetBSD: getpwent.c,v 1.48 2000/10/03 03:22:26 enami Exp
39  * and then gutted, leaving only /etc/master.passwd support.
40  */
41 
42 #include <sys/cdefs.h>
43 
44 #ifdef __weak_alias
45 #define endpwent		_endpwent
46 #define getpwent		_getpwent
47 #define getpwuid		_getpwuid
48 #define getpwnam		_getpwnam
49 #define setpwent		_setpwent
50 #define setpassent		_setpassent
51 
52 __weak_alias(endpwent,_endpwent)
53 __weak_alias(getpwent,_getpwent)
54 __weak_alias(getpwuid,_getpwuid)
55 __weak_alias(getpwnam,_getpwnam)
56 __weak_alias(setpwent,_setpwent)
57 __weak_alias(setpassent,_setpassent)
58 #endif
59 
60 #include <sys/param.h>
61 
62 #include <limits.h>
63 #include <pwd.h>
64 #include <stdlib.h>
65 #include <stdio.h>
66 #include <string.h>
67 
68 static	int		pwstart(void);
69 static	int		pwscan(int, uid_t, const char *);
70 static	int		pwmatchline(int, uid_t, const char *);
71 
72 static	FILE		*_pw_fp;
73 static	struct passwd	_pw_passwd;	/* password structure */
74 static	int		_pw_stayopen;	/* keep fd's open */
75 static	int		_pw_filesdone;
76 
77 #define	MAXLINELENGTH	1024
78 
79 static	char		pwline[MAXLINELENGTH];
80 
81 struct passwd *
82 getpwent(void)
83 {
84 
85 	if ((!_pw_fp && !pwstart()) || !pwscan(0, 0, NULL))
86 		return (NULL);
87 	return (&_pw_passwd);
88 }
89 
90 struct passwd *
91 getpwnam(const char *name)
92 {
93 	int rval;
94 
95 	if (!pwstart())
96 		return NULL;
97 	rval = pwscan(1, 0, name);
98 	if (!_pw_stayopen)
99 		endpwent();
100 	return (rval) ? &_pw_passwd : NULL;
101 }
102 
103 struct passwd *
104 getpwuid(uid_t uid)
105 {
106 	int rval;
107 
108 	if (!pwstart())
109 		return NULL;
110 	rval = pwscan(1, uid, NULL);
111 	if (!_pw_stayopen)
112 		endpwent();
113 	return (rval) ? &_pw_passwd : NULL;
114 }
115 
116 void
117 setpwent(void)
118 {
119 
120 	(void) setpassent(0);
121 }
122 
123 int
124 setpassent(int stayopen)
125 {
126 
127 	if (!pwstart())
128 		return 0;
129 	_pw_stayopen = stayopen;
130 	return 1;
131 }
132 
133 void
134 endpwent(void)
135 {
136 
137 	_pw_filesdone = 0;
138 	if (_pw_fp) {
139 		(void)fclose(_pw_fp);
140 		_pw_fp = NULL;
141 	}
142 }
143 
144 static int
145 pwstart(void)
146 {
147 
148 	_pw_filesdone = 0;
149 	if (_pw_fp) {
150 		rewind(_pw_fp);
151 		return 1;
152 	}
153 	return (_pw_fp = fopen(_PATH_MASTERPASSWD, "r")) ? 1 : 0;
154 }
155 
156 
157 static int
158 pwscan(int search, uid_t uid, const char *name)
159 {
160 
161 	if (_pw_filesdone)
162 		return 0;
163 	for (;;) {
164 		if (!fgets(pwline, sizeof(pwline), _pw_fp)) {
165 			if (!search)
166 				_pw_filesdone = 1;
167 			return 0;
168 		}
169 		/* skip lines that are too big */
170 		if (!strchr(pwline, '\n')) {
171 			int ch;
172 
173 			while ((ch = getc(_pw_fp)) != '\n' && ch != EOF)
174 				;
175 			continue;
176 		}
177 		if (pwmatchline(search, uid, name))
178 			return 1;
179 	}
180 	/* NOTREACHED */
181 }
182 
183 static int
184 pwmatchline(int search, uid_t uid, const char *name)
185 {
186 	unsigned long	id;
187 	char		*cp, *bp, *ep;
188 
189 	/* name may be NULL if search is nonzero */
190 
191 	bp = pwline;
192 	memset(&_pw_passwd, 0, sizeof(_pw_passwd));
193 	_pw_passwd.pw_name = strsep(&bp, ":\n");		/* name */
194 	if (search && name && strcmp(_pw_passwd.pw_name, name))
195 		return 0;
196 
197 	_pw_passwd.pw_passwd = strsep(&bp, ":\n");		/* passwd */
198 
199 	if (!(cp = strsep(&bp, ":\n")))				/* uid */
200 		return 0;
201 	id = strtoul(cp, &ep, 10);
202 	if (id > UID_MAX || *ep != '\0')
203 		return 0;
204 	_pw_passwd.pw_uid = (uid_t)id;
205 	if (search && name == NULL && _pw_passwd.pw_uid != uid)
206 		return 0;
207 
208 	if (!(cp = strsep(&bp, ":\n")))				/* gid */
209 		return 0;
210 	id = strtoul(cp, &ep, 10);
211 	if (id > GID_MAX || *ep != '\0')
212 		return 0;
213 	_pw_passwd.pw_gid = (gid_t)id;
214 
215 	if (!(_pw_passwd.pw_class = strsep(&bp, ":")))		/* class */
216 		return 0;
217 	if (!(ep = strsep(&bp, ":")))				/* change */
218 		return 0;
219 	if (!(ep = strsep(&bp, ":")))				/* expire */
220 		return 0;
221 
222 	if (!(_pw_passwd.pw_gecos = strsep(&bp, ":\n")))	/* gecos */
223 		return 0;
224 	if (!(_pw_passwd.pw_dir = strsep(&bp, ":\n")))		/* directory */
225 		return 0;
226 	if (!(_pw_passwd.pw_shell = strsep(&bp, ":\n")))	/* shell */
227 		return 0;
228 
229 	if (strchr(bp, ':') != NULL)
230 		return 0;
231 
232 	return 1;
233 }
234