xref: /freebsd/usr.sbin/pw/pw_vpw.c (revision 0957b409a90fd597c1e9124cbaf3edd2b488f4ac)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (C) 1996
5  *	David L. Nugent.  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  *
16  * THIS SOFTWARE IS PROVIDED BY DAVID L. NUGENT AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL DAVID L. NUGENT OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  */
29 
30 #ifndef lint
31 static const char rcsid[] =
32   "$FreeBSD$";
33 #endif /* not lint */
34 
35 #include <pwd.h>
36 #include <grp.h>
37 #include <libutil.h>
38 #include <stdio.h>
39 #include <string.h>
40 #include <stdlib.h>
41 #include <err.h>
42 #include <unistd.h>
43 
44 #include "pwupd.h"
45 
46 static FILE * pwd_fp = NULL;
47 static int pwd_scanflag;
48 static const char *pwd_filename;
49 
50 void
51 vendpwent(void)
52 {
53 	if (pwd_fp != NULL) {
54 		fclose(pwd_fp);
55 		pwd_fp = NULL;
56 	}
57 }
58 
59 void
60 vsetpwent(void)
61 {
62 	vendpwent();
63 }
64 
65 static struct passwd *
66 vnextpwent(char const *nam, uid_t uid, int doclose)
67 {
68 	struct passwd *pw;
69 	char *line;
70 	size_t linecap;
71 	ssize_t linelen;
72 
73 	pw = NULL;
74 	line = NULL;
75 	linecap = 0;
76 
77 	if (pwd_fp == NULL) {
78 		if (geteuid() == 0) {
79 			pwd_filename = _MASTERPASSWD;
80 			pwd_scanflag = PWSCAN_MASTER;
81 		} else {
82 			pwd_filename = _PASSWD;
83 			pwd_scanflag = 0;
84 		}
85 		pwd_fp = fopen(getpwpath(pwd_filename), "r");
86 	}
87 
88 	if (pwd_fp != NULL) {
89 		while ((linelen = getline(&line, &linecap, pwd_fp)) > 0) {
90 			/* Skip comments and empty lines */
91 			if (*line == '\n' || *line == '#')
92 				continue;
93 			/* trim latest \n */
94 			if (line[linelen - 1 ] == '\n')
95 				line[linelen - 1] = '\0';
96 			pw = pw_scan(line, pwd_scanflag);
97 			if (pw == NULL)
98 				errx(EXIT_FAILURE, "Invalid user entry in '%s':"
99 				    " '%s'", getpwpath(pwd_filename), line);
100 			if (uid != (uid_t)-1) {
101 				if (uid == pw->pw_uid)
102 					break;
103 			} else if (nam != NULL) {
104 				if (strcmp(nam, pw->pw_name) == 0)
105 					break;
106 			} else
107 				break;
108 			free(pw);
109 			pw = NULL;
110 		}
111 		if (doclose)
112 			vendpwent();
113 	}
114 	free(line);
115 
116 	return (pw);
117 }
118 
119 struct passwd *
120 vgetpwent(void)
121 {
122   return vnextpwent(NULL, -1, 0);
123 }
124 
125 struct passwd *
126 vgetpwuid(uid_t uid)
127 {
128   return vnextpwent(NULL, uid, 1);
129 }
130 
131 struct passwd *
132 vgetpwnam(const char * nam)
133 {
134   return vnextpwent(nam, -1, 1);
135 }
136 
137 
138 static FILE * grp_fp = NULL;
139 
140 void
141 vendgrent(void)
142 {
143 	if (grp_fp != NULL) {
144 		fclose(grp_fp);
145 		grp_fp = NULL;
146 	}
147 }
148 
149 void
150 vsetgrent(void)
151 {
152 	vendgrent();
153 }
154 
155 static struct group *
156 vnextgrent(char const *nam, gid_t gid, int doclose)
157 {
158 	struct group *gr;
159 	char *line;
160 	size_t linecap;
161 	ssize_t linelen;
162 
163 	gr = NULL;
164 	line = NULL;
165 	linecap = 0;
166 
167 	if (grp_fp != NULL || (grp_fp = fopen(getgrpath(_GROUP), "r")) != NULL) {
168 		while ((linelen = getline(&line, &linecap, grp_fp)) > 0) {
169 			/* Skip comments and empty lines */
170 			if (*line == '\n' || *line == '#')
171 				continue;
172 			/* trim latest \n */
173 			if (line[linelen - 1 ] == '\n')
174 				line[linelen - 1] = '\0';
175 			gr = gr_scan(line);
176 			if (gr == NULL)
177 				errx(EXIT_FAILURE, "Invalid group entry in '%s':"
178 				    " '%s'", getgrpath(_GROUP), line);
179 			if (gid != (gid_t)-1) {
180 				if (gid == gr->gr_gid)
181 					break;
182 			} else if (nam != NULL) {
183 				if (strcmp(nam, gr->gr_name) == 0)
184 					break;
185 			} else
186 				break;
187 			free(gr);
188 			gr = NULL;
189 		}
190 		if (doclose)
191 			vendgrent();
192 	}
193 	free(line);
194 
195 	return (gr);
196 }
197 
198 struct group *
199 vgetgrent(void)
200 {
201   return vnextgrent(NULL, -1, 0);
202 }
203 
204 
205 struct group *
206 vgetgrgid(gid_t gid)
207 {
208   return vnextgrent(NULL, gid, 1);
209 }
210 
211 struct group *
212 vgetgrnam(const char * nam)
213 {
214   return vnextgrent(nam, -1, 1);
215 }
216 
217