xref: /freebsd/usr.bin/chpass/field.c (revision a2f733abcff64628b7771a47089628b7327a88bd)
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 #endif
45 
46 #include <sys/cdefs.h>
47 #include <sys/param.h>
48 #include <sys/stat.h>
49 
50 #include <ctype.h>
51 #include <err.h>
52 #include <errno.h>
53 #include <grp.h>
54 #include <paths.h>
55 #include <pwd.h>
56 #include <stdlib.h>
57 #include <string.h>
58 
59 #include "chpass.h"
60 
61 /* ARGSUSED */
62 int
63 p_login(char *p, struct passwd *pw, ENTRY *ep __unused)
64 {
65 	if (!*p) {
66 		warnx("empty login field");
67 		return (-1);
68 	}
69 	if (*p == '-') {
70 		warnx("login names may not begin with a hyphen");
71 		return (-1);
72 	}
73 	if (!(pw->pw_name = strdup(p))) {
74 		warnx("can't save entry");
75 		return (-1);
76 	}
77 	if (strchr(p, '.'))
78 		warnx("\'.\' is dangerous in a login name");
79 	for (; *p; ++p)
80 		if (isupper(*p)) {
81 			warnx("upper-case letters are dangerous in a login name");
82 			break;
83 		}
84 	return (0);
85 }
86 
87 /* ARGSUSED */
88 int
89 p_passwd(char *p, struct passwd *pw, ENTRY *ep __unused)
90 {
91 	if (!(pw->pw_passwd = strdup(p))) {
92 		warnx("can't save password entry");
93 		return (-1);
94 	}
95 
96 	return (0);
97 }
98 
99 /* ARGSUSED */
100 int
101 p_uid(char *p, struct passwd *pw, ENTRY *ep __unused)
102 {
103 	uid_t id;
104 	char *np;
105 
106 	if (!*p) {
107 		warnx("empty uid field");
108 		return (-1);
109 	}
110 	if (!isdigit(*p)) {
111 		warnx("illegal uid");
112 		return (-1);
113 	}
114 	errno = 0;
115 	id = strtoul(p, &np, 10);
116 	if (*np || (id == (uid_t)ULONG_MAX && errno == ERANGE)) {
117 		warnx("illegal uid");
118 		return (-1);
119 	}
120 	pw->pw_uid = id;
121 	return (0);
122 }
123 
124 /* ARGSUSED */
125 int
126 p_gid(char *p, struct passwd *pw, ENTRY *ep __unused)
127 {
128 	struct group *gr;
129 	gid_t id;
130 	char *np;
131 
132 	if (!*p) {
133 		warnx("empty gid field");
134 		return (-1);
135 	}
136 	if (!isdigit(*p)) {
137 		if (!(gr = getgrnam(p))) {
138 			warnx("unknown group %s", p);
139 			return (-1);
140 		}
141 		pw->pw_gid = gr->gr_gid;
142 		return (0);
143 	}
144 	errno = 0;
145 	id = strtoul(p, &np, 10);
146 	if (*np || (id == (uid_t)ULONG_MAX && errno == ERANGE)) {
147 		warnx("illegal gid");
148 		return (-1);
149 	}
150 	pw->pw_gid = id;
151 	return (0);
152 }
153 
154 /* ARGSUSED */
155 int
156 p_class(char *p, struct passwd *pw, ENTRY *ep __unused)
157 {
158 	if (!(pw->pw_class = strdup(p))) {
159 		warnx("can't save entry");
160 		return (-1);
161 	}
162 
163 	return (0);
164 }
165 
166 /* ARGSUSED */
167 int
168 p_change(char *p, struct passwd *pw, ENTRY *ep __unused)
169 {
170 	if (!atot(p, &pw->pw_change))
171 		return (0);
172 	warnx("illegal date for change field");
173 	return (-1);
174 }
175 
176 /* ARGSUSED */
177 int
178 p_expire(char *p, struct passwd *pw, ENTRY *ep __unused)
179 {
180 	if (!atot(p, &pw->pw_expire))
181 		return (0);
182 	warnx("illegal date for expire field");
183 	return (-1);
184 }
185 
186 /* ARGSUSED */
187 int
188 p_gecos(char *p, struct passwd *pw __unused, ENTRY *ep)
189 {
190 	if (!(ep->save = strdup(p))) {
191 		warnx("can't save entry");
192 		return (-1);
193 	}
194 	return (0);
195 }
196 
197 /* ARGSUSED */
198 int
199 p_hdir(char *p, struct passwd *pw, ENTRY *ep __unused)
200 {
201 	if (!*p) {
202 		warnx("empty home directory field");
203 		return (-1);
204 	}
205 	if (!(pw->pw_dir = strdup(p))) {
206 		warnx("can't save entry");
207 		return (-1);
208 	}
209 	return (0);
210 }
211 
212 /* ARGSUSED */
213 int
214 p_shell(char *p, struct passwd *pw, ENTRY *ep __unused)
215 {
216 	struct stat sbuf;
217 
218 	if (!*p) {
219 		pw->pw_shell = strdup(_PATH_BSHELL);
220 		return (0);
221 	}
222 	/* only admin can change from or to "restricted" shells */
223 	if (!master_mode && pw->pw_shell && !ok_shell(pw->pw_shell)) {
224 		warnx("%s: current shell non-standard", pw->pw_shell);
225 		return (-1);
226 	}
227 	if (!ok_shell(p)) {
228 		if (!master_mode) {
229 			warnx("%s: non-standard shell", p);
230 			return (-1);
231 		}
232 		pw->pw_shell = strdup(p);
233 	}
234 	else
235 		pw->pw_shell = dup_shell(p);
236 	if (!pw->pw_shell) {
237 		warnx("can't save entry");
238 		return (-1);
239 	}
240 	if (stat(pw->pw_shell, &sbuf) < 0) {
241 		if (errno == ENOENT)
242 			warnx("WARNING: shell '%s' does not exist",
243 			    pw->pw_shell);
244 		else
245 			warn("WARNING: can't stat shell '%s'",  pw->pw_shell);
246 		return (0);
247 	}
248 	if (!S_ISREG(sbuf.st_mode)) {
249 		warnx("WARNING: shell '%s' is not a regular file",
250 			pw->pw_shell);
251 		return (0);
252 	}
253 	if ((sbuf.st_mode & (S_IXOTH | S_IXGRP | S_IXUSR)) == 0) {
254 		warnx("WARNING: shell '%s' is not executable", pw->pw_shell);
255 		return (0);
256 	}
257 	return (0);
258 }
259