xref: /freebsd/usr.bin/chpass/util.c (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
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 #ifndef lint
44 #if 0
45 static char sccsid[] = "@(#)util.c	8.4 (Berkeley) 4/2/94";
46 #endif
47 #endif /* not lint */
48 #include <sys/cdefs.h>
49 #include <sys/types.h>
50 
51 #include <ctype.h>
52 #include <stdint.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <string.h>
56 #include <time.h>
57 #include <unistd.h>
58 
59 #include "chpass.h"
60 
61 static const char *months[] =
62 	{ "January", "February", "March", "April", "May", "June",
63 	  "July", "August", "September", "October", "November",
64 	  "December", NULL };
65 
66 char *
67 ttoa(time_t tval)
68 {
69 	struct tm *tp;
70 	static char tbuf[50];
71 
72 	if (tval) {
73 		tp = localtime(&tval);
74 		(void)sprintf(tbuf, "%s %d, %d", months[tp->tm_mon],
75 		    tp->tm_mday, tp->tm_year + 1900);
76 	}
77 	else
78 		*tbuf = '\0';
79 	return (tbuf);
80 }
81 
82 int
83 atot(char *p, time_t *store)
84 {
85 	static struct tm *lt;
86 	char *t;
87 	const char **mp;
88 	time_t tval;
89 	int day, month, year;
90 
91 	if (!*p) {
92 		*store = 0;
93 		return (0);
94 	}
95 	if (!lt) {
96 		unsetenv("TZ");
97 		(void)time(&tval);
98 		lt = localtime(&tval);
99 	}
100 	if (!(t = strtok(p, " \t")))
101 		goto bad;
102 	if (isdigit(*t)) {
103 		month = atoi(t);
104 	} else {
105 		for (mp = months;; ++mp) {
106 			if (!*mp)
107 				goto bad;
108 			if (!strncasecmp(*mp, t, 3)) {
109 				month = mp - months + 1;
110 				break;
111 			}
112 		}
113 	}
114 	if (!(t = strtok(NULL, " \t,")) || !isdigit(*t))
115 		goto bad;
116 	day = atoi(t);
117 	if (!(t = strtok(NULL, " \t,")) || !isdigit(*t))
118 		goto bad;
119 	year = atoi(t);
120 	if (day < 1 || day > 31 || month < 1 || month > 12)
121 		goto bad;
122 	/* Allow two digit years 1969-2068 */
123 	if (year < 69)
124 		year += 2000;
125 	else if (year < 100)
126 		year += 1900;
127 	if (year < 1969)
128 bad:		return (1);
129 	lt->tm_year = year - 1900;
130 	lt->tm_mon = month - 1;
131 	lt->tm_mday = day;
132 	lt->tm_hour = 0;
133 	lt->tm_min = 0;
134 	lt->tm_sec = 0;
135 	lt->tm_isdst = -1;
136 	if ((tval = mktime(lt)) < 0)
137 		return (1);
138 #ifndef __i386__
139 	/*
140 	 * PR227589: The pwd.db and spwd.db files store the change and expire
141 	 * dates as unsigned 32-bit ints which overflow in 2106, so larger
142 	 * values must be rejected until the introduction of a v5 password
143 	 * database.  i386 has 32-bit time_t and so dates beyond y2038 are
144 	 * already rejected by mktime above.
145 	 */
146 	if (tval > UINT32_MAX)
147 		return (1);
148 #endif
149 	*store = tval;
150 	return (0);
151 }
152 
153 int
154 ok_shell(char *name)
155 {
156 	char *p, *sh;
157 
158 	setusershell();
159 	while ((sh = getusershell())) {
160 		if (!strcmp(name, sh)) {
161 			endusershell();
162 			return (1);
163 		}
164 		/* allow just shell name, but use "real" path */
165 		if ((p = strrchr(sh, '/')) && strcmp(name, p + 1) == 0) {
166 			endusershell();
167 			return (1);
168 		}
169 	}
170 	endusershell();
171 	return (0);
172 }
173 
174 char *
175 dup_shell(char *name)
176 {
177 	char *p, *sh, *ret;
178 
179 	setusershell();
180 	while ((sh = getusershell())) {
181 		if (!strcmp(name, sh)) {
182 			endusershell();
183 			return (strdup(name));
184 		}
185 		/* allow just shell name, but use "real" path */
186 		if ((p = strrchr(sh, '/')) && strcmp(name, p + 1) == 0) {
187 			ret = strdup(sh);
188 			endusershell();
189 			return (ret);
190 		}
191 	}
192 	endusershell();
193 	return (NULL);
194 }
195