xref: /freebsd/usr.bin/chpass/field.c (revision 8881d206f4e68b564c2c5f50fc717086fc3e827a)
1 /*-
2  * SPDX-License-Identifier: BSD-4-Clause
3  *
4  * Copyright (c) 1988, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  * Copyright (c) 2002 Networks Associates Technology, Inc.
7  * All rights reserved.
8  *
9  * Portions of this software were developed for the FreeBSD Project by
10  * ThinkSec AS and NAI Labs, the Security Research Division of Network
11  * Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
12  * ("CBOSS"), as part of the DARPA CHATS research program.
13  *
14  * Redistribution and use in source and binary forms, with or without
15  * modification, are permitted provided that the following conditions
16  * are met:
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  * 2. Redistributions in binary form must reproduce the above copyright
20  *    notice, this list of conditions and the following disclaimer in the
21  *    documentation and/or other materials provided with the distribution.
22  * 3. All advertising materials mentioning features or use of this software
23  *    must display the following acknowledgement:
24  *	This product includes software developed by the University of
25  *	California, Berkeley and its contributors.
26  * 4. Neither the name of the University nor the names of its contributors
27  *    may be used to endorse or promote products derived from this software
28  *    without specific prior written permission.
29  *
30  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
31  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
32  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
34  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
35  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
36  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
37  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
38  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
39  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40  * SUCH DAMAGE.
41  */
42 
43 #if 0
44 #ifndef lint
45 static char sccsid[] = "@(#)field.c	8.4 (Berkeley) 4/2/94";
46 #endif /* not lint */
47 #endif
48 
49 #include <sys/cdefs.h>
50 __FBSDID("$FreeBSD$");
51 
52 #include <sys/param.h>
53 #include <sys/stat.h>
54 
55 #include <ctype.h>
56 #include <err.h>
57 #include <errno.h>
58 #include <grp.h>
59 #include <paths.h>
60 #include <pwd.h>
61 #include <stdlib.h>
62 #include <string.h>
63 
64 #include "chpass.h"
65 
66 /* ARGSUSED */
67 int
68 p_login(char *p, struct passwd *pw, ENTRY *ep __unused)
69 {
70 	if (!*p) {
71 		warnx("empty login field");
72 		return (-1);
73 	}
74 	if (*p == '-') {
75 		warnx("login names may not begin with a hyphen");
76 		return (-1);
77 	}
78 	if (!(pw->pw_name = strdup(p))) {
79 		warnx("can't save entry");
80 		return (-1);
81 	}
82 	if (strchr(p, '.'))
83 		warnx("\'.\' is dangerous in a login name");
84 	for (; *p; ++p)
85 		if (isupper(*p)) {
86 			warnx("upper-case letters are dangerous in a login name");
87 			break;
88 		}
89 	return (0);
90 }
91 
92 /* ARGSUSED */
93 int
94 p_passwd(char *p, struct passwd *pw, ENTRY *ep __unused)
95 {
96 	if (!(pw->pw_passwd = strdup(p))) {
97 		warnx("can't save password entry");
98 		return (-1);
99 	}
100 
101 	return (0);
102 }
103 
104 /* ARGSUSED */
105 int
106 p_uid(char *p, struct passwd *pw, ENTRY *ep __unused)
107 {
108 	uid_t id;
109 	char *np;
110 
111 	if (!*p) {
112 		warnx("empty uid field");
113 		return (-1);
114 	}
115 	if (!isdigit(*p)) {
116 		warnx("illegal uid");
117 		return (-1);
118 	}
119 	errno = 0;
120 	id = strtoul(p, &np, 10);
121 	if (*np || (id == (uid_t)ULONG_MAX && errno == ERANGE)) {
122 		warnx("illegal uid");
123 		return (-1);
124 	}
125 	pw->pw_uid = id;
126 	return (0);
127 }
128 
129 /* ARGSUSED */
130 int
131 p_gid(char *p, struct passwd *pw, ENTRY *ep __unused)
132 {
133 	struct group *gr;
134 	gid_t id;
135 	char *np;
136 
137 	if (!*p) {
138 		warnx("empty gid field");
139 		return (-1);
140 	}
141 	if (!isdigit(*p)) {
142 		if (!(gr = getgrnam(p))) {
143 			warnx("unknown group %s", p);
144 			return (-1);
145 		}
146 		pw->pw_gid = gr->gr_gid;
147 		return (0);
148 	}
149 	errno = 0;
150 	id = strtoul(p, &np, 10);
151 	if (*np || (id == (uid_t)ULONG_MAX && errno == ERANGE)) {
152 		warnx("illegal gid");
153 		return (-1);
154 	}
155 	pw->pw_gid = id;
156 	return (0);
157 }
158 
159 /* ARGSUSED */
160 int
161 p_class(char *p, struct passwd *pw, ENTRY *ep __unused)
162 {
163 	if (!(pw->pw_class = strdup(p))) {
164 		warnx("can't save entry");
165 		return (-1);
166 	}
167 
168 	return (0);
169 }
170 
171 /* ARGSUSED */
172 int
173 p_change(char *p, struct passwd *pw, ENTRY *ep __unused)
174 {
175 	if (!atot(p, &pw->pw_change))
176 		return (0);
177 	warnx("illegal date for change field");
178 	return (-1);
179 }
180 
181 /* ARGSUSED */
182 int
183 p_expire(char *p, struct passwd *pw, ENTRY *ep __unused)
184 {
185 	if (!atot(p, &pw->pw_expire))
186 		return (0);
187 	warnx("illegal date for expire field");
188 	return (-1);
189 }
190 
191 /* ARGSUSED */
192 int
193 p_gecos(char *p, struct passwd *pw __unused, ENTRY *ep)
194 {
195 	if (!(ep->save = strdup(p))) {
196 		warnx("can't save entry");
197 		return (-1);
198 	}
199 	return (0);
200 }
201 
202 /* ARGSUSED */
203 int
204 p_hdir(char *p, struct passwd *pw, ENTRY *ep __unused)
205 {
206 	if (!*p) {
207 		warnx("empty home directory field");
208 		return (-1);
209 	}
210 	if (!(pw->pw_dir = strdup(p))) {
211 		warnx("can't save entry");
212 		return (-1);
213 	}
214 	return (0);
215 }
216 
217 /* ARGSUSED */
218 int
219 p_shell(char *p, struct passwd *pw, ENTRY *ep __unused)
220 {
221 	struct stat sbuf;
222 
223 	if (!*p) {
224 		pw->pw_shell = strdup(_PATH_BSHELL);
225 		return (0);
226 	}
227 	/* only admin can change from or to "restricted" shells */
228 	if (!master_mode && pw->pw_shell && !ok_shell(pw->pw_shell)) {
229 		warnx("%s: current shell non-standard", pw->pw_shell);
230 		return (-1);
231 	}
232 	if (!ok_shell(p)) {
233 		if (!master_mode) {
234 			warnx("%s: non-standard shell", p);
235 			return (-1);
236 		}
237 		pw->pw_shell = strdup(p);
238 	}
239 	else
240 		pw->pw_shell = dup_shell(p);
241 	if (!pw->pw_shell) {
242 		warnx("can't save entry");
243 		return (-1);
244 	}
245 	if (stat(pw->pw_shell, &sbuf) < 0) {
246 		if (errno == ENOENT)
247 			warnx("WARNING: shell '%s' does not exist",
248 			    pw->pw_shell);
249 		else
250 			warn("WARNING: can't stat shell '%s'",  pw->pw_shell);
251 		return (0);
252 	}
253 	if (!S_ISREG(sbuf.st_mode)) {
254 		warnx("WARNING: shell '%s' is not a regular file",
255 			pw->pw_shell);
256 		return (0);
257 	}
258 	if ((sbuf.st_mode & (S_IXOTH | S_IXGRP | S_IXUSR)) == 0) {
259 		warnx("WARNING: shell '%s' is not executable", pw->pw_shell);
260 		return (0);
261 	}
262 	return (0);
263 }
264