xref: /freebsd/usr.bin/chpass/field.c (revision 641a6cfb86023499caafe26a4d821a0b885cf00b)
1 /*
2  * Copyright (c) 1988, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  * Copyright (c) 2002 Networks Associates Technology, Inc.
5  * All rights reserved.
6  *
7  * Portions of this software were developed for the FreeBSD Project by
8  * ThinkSec AS and NAI Labs, the Security Research Division of Network
9  * Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
10  * ("CBOSS"), as part of the DARPA CHATS research program.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. All advertising materials mentioning features or use of this software
21  *    must display the following acknowledgement:
22  *	This product includes software developed by the University of
23  *	California, Berkeley and its contributors.
24  * 4. Neither the name of the University nor the names of its contributors
25  *    may be used to endorse or promote products derived from this software
26  *    without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  */
40 
41 #if 0
42 #ifndef lint
43 static char sccsid[] = "@(#)field.c	8.4 (Berkeley) 4/2/94";
44 #endif /* not lint */
45 #endif
46 
47 #include <sys/cdefs.h>
48 __FBSDID("$FreeBSD$");
49 
50 #include <sys/param.h>
51 #include <sys/stat.h>
52 
53 #include <ctype.h>
54 #include <err.h>
55 #include <errno.h>
56 #include <grp.h>
57 #include <paths.h>
58 #include <pwd.h>
59 #include <stdlib.h>
60 #include <string.h>
61 
62 #include "chpass.h"
63 
64 /* ARGSUSED */
65 int
66 p_login(char *p, struct passwd *pw, ENTRY *ep __unused)
67 {
68 	if (!*p) {
69 		warnx("empty login field");
70 		return (-1);
71 	}
72 	if (*p == '-') {
73 		warnx("login names may not begin with a hyphen");
74 		return (-1);
75 	}
76 	if (!(pw->pw_name = strdup(p))) {
77 		warnx("can't save entry");
78 		return (-1);
79 	}
80 	if (strchr(p, '.'))
81 		warnx("\'.\' is dangerous in a login name");
82 	for (; *p; ++p)
83 		if (isupper(*p)) {
84 			warnx("upper-case letters are dangerous in a login name");
85 			break;
86 		}
87 	return (0);
88 }
89 
90 /* ARGSUSED */
91 int
92 p_passwd(char *p, struct passwd *pw, ENTRY *ep __unused)
93 {
94 	if (!(pw->pw_passwd = strdup(p))) {
95 		warnx("can't save password entry");
96 		return (-1);
97 	}
98 
99 	return (0);
100 }
101 
102 /* ARGSUSED */
103 int
104 p_uid(char *p, struct passwd *pw, ENTRY *ep __unused)
105 {
106 	uid_t id;
107 	char *np;
108 
109 	if (!*p) {
110 		warnx("empty uid field");
111 		return (-1);
112 	}
113 	if (!isdigit(*p)) {
114 		warnx("illegal uid");
115 		return (-1);
116 	}
117 	errno = 0;
118 	id = strtoul(p, &np, 10);
119 	if (*np || (id == (uid_t)ULONG_MAX && errno == ERANGE)) {
120 		warnx("illegal uid");
121 		return (-1);
122 	}
123 	pw->pw_uid = id;
124 	return (0);
125 }
126 
127 /* ARGSUSED */
128 int
129 p_gid(char *p, struct passwd *pw, ENTRY *ep __unused)
130 {
131 	struct group *gr;
132 	gid_t id;
133 	char *np;
134 
135 	if (!*p) {
136 		warnx("empty gid field");
137 		return (-1);
138 	}
139 	if (!isdigit(*p)) {
140 		if (!(gr = getgrnam(p))) {
141 			warnx("unknown group %s", p);
142 			return (-1);
143 		}
144 		pw->pw_gid = gr->gr_gid;
145 		return (0);
146 	}
147 	errno = 0;
148 	id = strtoul(p, &np, 10);
149 	if (*np || (id == (uid_t)ULONG_MAX && errno == ERANGE)) {
150 		warnx("illegal gid");
151 		return (-1);
152 	}
153 	pw->pw_gid = id;
154 	return (0);
155 }
156 
157 /* ARGSUSED */
158 int
159 p_class(char *p, struct passwd *pw, ENTRY *ep __unused)
160 {
161 	if (!(pw->pw_class = strdup(p))) {
162 		warnx("can't save entry");
163 		return (-1);
164 	}
165 
166 	return (0);
167 }
168 
169 /* ARGSUSED */
170 int
171 p_change(char *p, struct passwd *pw, ENTRY *ep __unused)
172 {
173 	if (!atot(p, &pw->pw_change))
174 		return (0);
175 	warnx("illegal date for change field");
176 	return (-1);
177 }
178 
179 /* ARGSUSED */
180 int
181 p_expire(char *p, struct passwd *pw, ENTRY *ep __unused)
182 {
183 	if (!atot(p, &pw->pw_expire))
184 		return (0);
185 	warnx("illegal date for expire field");
186 	return (-1);
187 }
188 
189 /* ARGSUSED */
190 int
191 p_gecos(char *p, struct passwd *pw __unused, ENTRY *ep)
192 {
193 	if (!(ep->save = strdup(p))) {
194 		warnx("can't save entry");
195 		return (-1);
196 	}
197 	return (0);
198 }
199 
200 /* ARGSUSED */
201 int
202 p_hdir(char *p, struct passwd *pw, ENTRY *ep __unused)
203 {
204 	if (!*p) {
205 		warnx("empty home directory field");
206 		return (-1);
207 	}
208 	if (!(pw->pw_dir = strdup(p))) {
209 		warnx("can't save entry");
210 		return (-1);
211 	}
212 	return (0);
213 }
214 
215 /* ARGSUSED */
216 int
217 p_shell(char *p, struct passwd *pw, ENTRY *ep __unused)
218 {
219 	struct stat sbuf;
220 
221 	if (!*p) {
222 		pw->pw_shell = strdup(_PATH_BSHELL);
223 		return (0);
224 	}
225 	/* only admin can change from or to "restricted" shells */
226 	if (!master_mode && pw->pw_shell && !ok_shell(pw->pw_shell)) {
227 		warnx("%s: current shell non-standard", pw->pw_shell);
228 		return (-1);
229 	}
230 	if (!ok_shell(p)) {
231 		if (!master_mode) {
232 			warnx("%s: non-standard shell", p);
233 			return (-1);
234 		}
235 		pw->pw_shell = strdup(p);
236 	}
237 	else
238 		pw->pw_shell = dup_shell(p);
239 	if (!pw->pw_shell) {
240 		warnx("can't save entry");
241 		return (-1);
242 	}
243 	if (stat(pw->pw_shell, &sbuf) < 0) {
244 		if (errno == ENOENT)
245 			warnx("WARNING: shell '%s' does not exist",
246 			    pw->pw_shell);
247 		else
248 			warn("WARNING: can't stat shell '%s'",  pw->pw_shell);
249 		return (0);
250 	}
251 	if (!S_ISREG(sbuf.st_mode)) {
252 		warnx("WARNING: shell '%s' is not a regular file",
253 			pw->pw_shell);
254 		return (0);
255 	}
256 	if ((sbuf.st_mode & (S_IXOTH | S_IXGRP | S_IXUSR)) == 0) {
257 		warnx("WARNING: shell '%s' is not executable", pw->pw_shell);
258 		return (0);
259 	}
260 	return (0);
261 }
262