xref: /freebsd/usr.sbin/pw/pw_vpw.c (revision eba230afba4932f02a1ca44efc797cf7499a5cb0)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 #include <pwd.h>
31 #include <grp.h>
32 #include <libutil.h>
33 #include <stdio.h>
34 #include <string.h>
35 #include <stdlib.h>
36 #include <err.h>
37 #include <unistd.h>
38 
39 #include "pwupd.h"
40 
41 static FILE * pwd_fp = NULL;
42 static int pwd_scanflag;
43 static const char *pwd_filename;
44 
45 void
vendpwent(void)46 vendpwent(void)
47 {
48 	if (pwd_fp != NULL) {
49 		fclose(pwd_fp);
50 		pwd_fp = NULL;
51 	}
52 }
53 
54 void
vsetpwent(void)55 vsetpwent(void)
56 {
57 	vendpwent();
58 }
59 
60 static struct passwd *
vnextpwent(char const * nam,uid_t uid,int doclose)61 vnextpwent(char const *nam, uid_t uid, int doclose)
62 {
63 	struct passwd *pw;
64 	char *line;
65 	size_t linecap;
66 	ssize_t linelen;
67 
68 	pw = NULL;
69 	line = NULL;
70 	linecap = 0;
71 
72 	if (pwd_fp == NULL) {
73 		if (geteuid() == 0) {
74 			pwd_filename = _MASTERPASSWD;
75 			pwd_scanflag = PWSCAN_MASTER;
76 		} else {
77 			pwd_filename = _PASSWD;
78 			pwd_scanflag = 0;
79 		}
80 		pwd_fp = fopen(getpwpath(pwd_filename), "r");
81 	}
82 
83 	if (pwd_fp != NULL) {
84 		while ((linelen = getline(&line, &linecap, pwd_fp)) > 0) {
85 			/* Skip comments and empty lines */
86 			if (*line == '\n' || *line == '#')
87 				continue;
88 			/* trim latest \n */
89 			if (line[linelen - 1 ] == '\n')
90 				line[linelen - 1] = '\0';
91 			pw = pw_scan(line, pwd_scanflag);
92 			if (pw == NULL)
93 				errx(EXIT_FAILURE, "Invalid user entry in '%s':"
94 				    " '%s'", getpwpath(pwd_filename), line);
95 			if (uid != (uid_t)-1) {
96 				if (uid == pw->pw_uid)
97 					break;
98 			} else if (nam != NULL) {
99 				if (strcmp(nam, pw->pw_name) == 0)
100 					break;
101 			} else
102 				break;
103 			free(pw);
104 			pw = NULL;
105 		}
106 		if (doclose)
107 			vendpwent();
108 	}
109 	free(line);
110 
111 	return (pw);
112 }
113 
114 struct passwd *
vgetpwent(void)115 vgetpwent(void)
116 {
117   return vnextpwent(NULL, -1, 0);
118 }
119 
120 struct passwd *
vgetpwuid(uid_t uid)121 vgetpwuid(uid_t uid)
122 {
123   return vnextpwent(NULL, uid, 1);
124 }
125 
126 struct passwd *
vgetpwnam(const char * nam)127 vgetpwnam(const char * nam)
128 {
129   return vnextpwent(nam, -1, 1);
130 }
131 
132 
133 static FILE * grp_fp = NULL;
134 
135 void
vendgrent(void)136 vendgrent(void)
137 {
138 	if (grp_fp != NULL) {
139 		fclose(grp_fp);
140 		grp_fp = NULL;
141 	}
142 }
143 
144 void
vsetgrent(void)145 vsetgrent(void)
146 {
147 	vendgrent();
148 }
149 
150 static struct group *
vnextgrent(char const * nam,gid_t gid,int doclose)151 vnextgrent(char const *nam, gid_t gid, int doclose)
152 {
153 	struct group *gr;
154 	char *line;
155 	size_t linecap;
156 	ssize_t linelen;
157 
158 	gr = NULL;
159 	line = NULL;
160 	linecap = 0;
161 
162 	if (grp_fp != NULL || (grp_fp = fopen(getgrpath(_GROUP), "r")) != NULL) {
163 		while ((linelen = getline(&line, &linecap, grp_fp)) > 0) {
164 			/* Skip comments and empty lines */
165 			if (*line == '\n' || *line == '#')
166 				continue;
167 			/* trim latest \n */
168 			if (line[linelen - 1 ] == '\n')
169 				line[linelen - 1] = '\0';
170 			gr = gr_scan(line);
171 			if (gr == NULL)
172 				errx(EXIT_FAILURE, "Invalid group entry in '%s':"
173 				    " '%s'", getgrpath(_GROUP), line);
174 			if (gid != (gid_t)-1) {
175 				if (gid == gr->gr_gid)
176 					break;
177 			} else if (nam != NULL) {
178 				if (strcmp(nam, gr->gr_name) == 0)
179 					break;
180 			} else
181 				break;
182 			free(gr);
183 			gr = NULL;
184 		}
185 		if (doclose)
186 			vendgrent();
187 	}
188 	free(line);
189 
190 	return (gr);
191 }
192 
193 struct group *
vgetgrent(void)194 vgetgrent(void)
195 {
196   return vnextgrent(NULL, -1, 0);
197 }
198 
199 
200 struct group *
vgetgrgid(gid_t gid)201 vgetgrgid(gid_t gid)
202 {
203   return vnextgrent(NULL, gid, 1);
204 }
205 
206 struct group *
vgetgrnam(const char * nam)207 vgetgrnam(const char * nam)
208 {
209   return vnextgrent(nam, -1, 1);
210 }
211 
212