xref: /freebsd/lib/libc/gen/pw_scan.c (revision 9207b4cff7b8d483f4dd3c62266c2b58819eb7f9)
1 /*-
2  * Copyright (c) 1990, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 #if 0
36 static char sccsid[] = "@(#)pw_scan.c	8.3 (Berkeley) 4/2/94";
37 #endif
38 static const char rcsid[] =
39   "$FreeBSD$";
40 #endif /* not lint */
41 
42 /*
43  * This module is used to "verify" password entries by chpass(1) and
44  * pwd_mkdb(8).
45  */
46 
47 #include <sys/param.h>
48 
49 #include <err.h>
50 #include <errno.h>
51 #include <fcntl.h>
52 #include <pwd.h>
53 #include <stdio.h>
54 #include <string.h>
55 #include <stdlib.h>
56 #include <unistd.h>
57 
58 #include "pw_scan.h"
59 
60 /*
61  * Some software assumes that IDs are short.  We should emit warnings
62  * for id's which can not be stored in a short, but we are more liberal
63  * by default, warning for IDs greater than USHRT_MAX.
64  *
65  * If pw_big_ids_warning is anything other than -1 on entry to pw_scan()
66  * it will be set based on the existance of PW_SCAN_BIG_IDS in the
67  * environment.
68  */
69 static int	pw_big_ids_warning = -1;
70 
71 int
72 __pw_scan(char *bp, struct passwd *pw, int flags)
73 {
74 	uid_t id;
75 	int root;
76 	char *p, *sh;
77 
78 	if (pw_big_ids_warning == -1)
79 		pw_big_ids_warning = getenv("PW_SCAN_BIG_IDS") == NULL ? 1 : 0;
80 
81 	pw->pw_fields = 0;
82 	if (!(pw->pw_name = strsep(&bp, ":")))		/* login */
83 		goto fmt;
84 	root = !strcmp(pw->pw_name, "root");
85 	if (pw->pw_name[0] && (pw->pw_name[0] != '+' || pw->pw_name[1] == '\0'))
86 		pw->pw_fields |= _PWF_NAME;
87 
88 	if (!(pw->pw_passwd = strsep(&bp, ":")))	/* passwd */
89 		goto fmt;
90 	if (pw->pw_passwd[0])
91 		pw->pw_fields |= _PWF_PASSWD;
92 
93 	if (!(p = strsep(&bp, ":")))			/* uid */
94 		goto fmt;
95 	if (p[0])
96 		pw->pw_fields |= _PWF_UID;
97 	else {
98 		if (pw->pw_name[0] != '+' && pw->pw_name[0] != '-') {
99 			if (flags & _PWSCAN_WARN)
100 				warnx("no uid for user %s", pw->pw_name);
101 			return (0);
102 		}
103 	}
104 	id = strtoul(p, (char **)NULL, 10);
105 	if (errno == ERANGE) {
106 		if (flags & _PWSCAN_WARN)
107 			warnx("%s > max uid value (%lu)", p, ULONG_MAX);
108 		return (0);
109 	}
110 	if (root && id) {
111 		if (flags & _PWSCAN_WARN)
112 			warnx("root uid should be 0");
113 		return (0);
114 	}
115 	if (flags & _PWSCAN_WARN && pw_big_ids_warning && id > USHRT_MAX) {
116 		warnx("%s > recommended max uid value (%u)", p, USHRT_MAX);
117 		/*return (0);*/ /* THIS SHOULD NOT BE FATAL! */
118 	}
119 	pw->pw_uid = id;
120 
121 	if (!(p = strsep(&bp, ":")))			/* gid */
122 		goto fmt;
123 	if (p[0])
124 		pw->pw_fields |= _PWF_GID;
125 	id = strtoul(p, (char **)NULL, 10);
126 	if (errno == ERANGE) {
127 		if (flags & _PWSCAN_WARN)
128 			warnx("%s > max gid value (%lu)", p, ULONG_MAX);
129 		return (0);
130 	}
131 	if (flags & _PWSCAN_WARN && pw_big_ids_warning && id > USHRT_MAX) {
132 		warnx("%s > recommended max gid value (%u)", p, USHRT_MAX);
133 		/* return (0); This should not be fatal! */
134 	}
135 	pw->pw_gid = id;
136 
137 	if (flags & _PWSCAN_MASTER ) {
138 		if (!(pw->pw_class = strsep(&bp, ":")))	/* class */
139 			goto fmt;
140 		if (pw->pw_class[0])
141 			pw->pw_fields |= _PWF_CLASS;
142 
143 		if (!(p = strsep(&bp, ":")))		/* change */
144 			goto fmt;
145 		if (p[0])
146 			pw->pw_fields |= _PWF_CHANGE;
147 		pw->pw_change = atol(p);
148 
149 		if (!(p = strsep(&bp, ":")))		/* expire */
150 			goto fmt;
151 		if (p[0])
152 			pw->pw_fields |= _PWF_EXPIRE;
153 		pw->pw_expire = atol(p);
154 	}
155 	if (!(pw->pw_gecos = strsep(&bp, ":")))		/* gecos */
156 		goto fmt;
157 	if (pw->pw_gecos[0])
158 		pw->pw_fields |= _PWF_GECOS;
159 
160 	if (!(pw->pw_dir = strsep(&bp, ":")))		/* directory */
161 		goto fmt;
162 	if (pw->pw_dir[0])
163 		pw->pw_fields |= _PWF_DIR;
164 
165 	if (!(pw->pw_shell = strsep(&bp, ":")))		/* shell */
166 		goto fmt;
167 
168 	p = pw->pw_shell;
169 	if (root && *p)					/* empty == /bin/sh */
170 		for (setusershell();;) {
171 			if (!(sh = getusershell())) {
172 				if (flags & _PWSCAN_WARN)
173 					warnx("warning, unknown root shell");
174 				break;
175 			}
176 			if (!strcmp(p, sh))
177 				break;
178 		}
179 	if (p[0])
180 		pw->pw_fields |= _PWF_SHELL;
181 
182 	if ((p = strsep(&bp, ":"))) {			/* too many */
183 fmt:
184 		if (flags & _PWSCAN_WARN)
185 			warnx("corrupted entry");
186 		return (0);
187 	}
188 	return (1);
189 }
190