xref: /dragonfly/lib/libc/gen/pw_scan.c (revision 19fe1c42)
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  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * @(#)pw_scan.c	8.3 (Berkeley) 4/2/94
30  * $FreeBSD: src/lib/libc/gen/pw_scan.c,v 1.26 2007/01/09 00:27:55 imp Exp $
31  * $DragonFly: src/usr.sbin/pwd_mkdb/pw_scan.c,v 1.3 2005/12/05 02:40:27 swildner Exp $
32  */
33 
34 /*
35  * This module is used to "verify" password entries by chpass(1) and
36  * pwd_mkdb(8).
37  */
38 
39 #include <sys/param.h>
40 
41 #include <err.h>
42 #include <errno.h>
43 #include <fcntl.h>
44 #include <pwd.h>
45 #include <stdio.h>
46 #include <string.h>
47 #include <stdlib.h>
48 #include <unistd.h>
49 
50 #include "pw_scan.h"
51 
52 /*
53  * Some software assumes that IDs are short.  We should emit warnings
54  * for id's which cannot be stored in a short, but we are more liberal
55  * by default, warning for IDs greater than USHRT_MAX.
56  *
57  * If pw_big_ids_warning is -1 on entry to pw_scan(), it will be set based
58  * on the existence of PW_SCAN_BIG_IDS in the environment.
59  */
60 static int	pw_big_ids_warning = -1;
61 
62 int
63 __pw_scan(char *bp, struct passwd *pw, int flags)
64 {
65 	uid_t id;
66 	int root;
67 	char *ep, *p, *sh;
68 
69 	if (pw_big_ids_warning == -1)
70 		pw_big_ids_warning = getenv("PW_SCAN_BIG_IDS") == NULL ? 1 : 0;
71 
72 	pw->pw_fields = 0;
73 	if (!(pw->pw_name = strsep(&bp, ":")))		/* login */
74 		goto fmt;
75 	root = !strcmp(pw->pw_name, "root");
76 	if (pw->pw_name[0] && (pw->pw_name[0] != '+' || pw->pw_name[1] == '\0'))
77 		pw->pw_fields |= _PWF_NAME;
78 
79 	if (!(pw->pw_passwd = strsep(&bp, ":")))	/* passwd */
80 		goto fmt;
81 	if (pw->pw_passwd[0])
82 		pw->pw_fields |= _PWF_PASSWD;
83 
84 	if (!(p = strsep(&bp, ":")))			/* uid */
85 		goto fmt;
86 	if (p[0])
87 		pw->pw_fields |= _PWF_UID;
88 	else {
89 		if (pw->pw_name[0] != '+' && pw->pw_name[0] != '-') {
90 			if (flags & _PWSCAN_WARN)
91 				warnx("no uid for user %s", pw->pw_name);
92 			return (0);
93 		}
94 	}
95 	id = strtoul(p, &ep, 10);
96 	if (errno == ERANGE) {
97 		if (flags & _PWSCAN_WARN)
98 			warnx("%s > max uid value (%lu)", p, ULONG_MAX);
99 		return (0);
100 	}
101 	if (*ep != '\0') {
102 		if (flags & _PWSCAN_WARN)
103 			warnx("%s uid is incorrect", p);
104 		return (0);
105 	}
106 	if (root && id) {
107 		if (flags & _PWSCAN_WARN)
108 			warnx("root uid should be 0");
109 		return (0);
110 	}
111 	if (flags & _PWSCAN_WARN && pw_big_ids_warning && id > USHRT_MAX) {
112 		warnx("%s > recommended max uid value (%u)", p, USHRT_MAX);
113 		/*return (0);*/ /* THIS SHOULD NOT BE FATAL! */
114 	}
115 	pw->pw_uid = id;
116 
117 	if (!(p = strsep(&bp, ":")))			/* gid */
118 		goto fmt;
119 	if (p[0])
120 		pw->pw_fields |= _PWF_GID;
121 	else {
122 		if (pw->pw_name[0] != '+' && pw->pw_name[0] != '-') {
123 			if (flags & _PWSCAN_WARN)
124 				warnx("no gid for user %s", pw->pw_name);
125 			return (0);
126 		}
127 	}
128 	id = strtoul(p, &ep, 10);
129 	if (errno == ERANGE) {
130 		if (flags & _PWSCAN_WARN)
131 			warnx("%s > max gid value (%lu)", p, ULONG_MAX);
132 		return (0);
133 	}
134 	if (*ep != '\0') {
135 		if (flags & _PWSCAN_WARN)
136 			warnx("%s gid is incorrect", p);
137 		return (0);
138 	}
139 	if (flags & _PWSCAN_WARN && pw_big_ids_warning && id > USHRT_MAX) {
140 		warnx("%s > recommended max gid value (%u)", p, USHRT_MAX);
141 		/* return (0); This should not be fatal! */
142 	}
143 	pw->pw_gid = id;
144 
145 	if (flags & _PWSCAN_MASTER ) {
146 		if (!(pw->pw_class = strsep(&bp, ":")))	/* class */
147 			goto fmt;
148 		if (pw->pw_class[0])
149 			pw->pw_fields |= _PWF_CLASS;
150 
151 		if (!(p = strsep(&bp, ":")))		/* change */
152 			goto fmt;
153 		if (p[0])
154 			pw->pw_fields |= _PWF_CHANGE;
155 		pw->pw_change = atol(p);
156 
157 		if (!(p = strsep(&bp, ":")))		/* expire */
158 			goto fmt;
159 		if (p[0])
160 			pw->pw_fields |= _PWF_EXPIRE;
161 		pw->pw_expire = atol(p);
162 	}
163 	if (!(pw->pw_gecos = strsep(&bp, ":")))		/* gecos */
164 		goto fmt;
165 	if (pw->pw_gecos[0])
166 		pw->pw_fields |= _PWF_GECOS;
167 
168 	if (!(pw->pw_dir = strsep(&bp, ":")))		/* directory */
169 		goto fmt;
170 	if (pw->pw_dir[0])
171 		pw->pw_fields |= _PWF_DIR;
172 
173 	if (!(pw->pw_shell = strsep(&bp, ":")))		/* shell */
174 		goto fmt;
175 
176 	p = pw->pw_shell;
177 	if (root && *p) {				/* empty == /bin/sh */
178 		for (setusershell();;) {
179 			if (!(sh = getusershell())) {
180 				if (flags & _PWSCAN_WARN)
181 					warnx("warning, unknown root shell");
182 				break;
183 			}
184 			if (!strcmp(p, sh))
185 				break;
186 		}
187 		endusershell();
188 	}
189 	if (p[0])
190 		pw->pw_fields |= _PWF_SHELL;
191 
192 	if ((p = strsep(&bp, ":"))) {			/* too many */
193 fmt:
194 		if (flags & _PWSCAN_WARN)
195 			warnx("corrupted entry");
196 		return (0);
197 	}
198 	return (1);
199 }
200