xref: /openbsd-src/lib/libutil/check_expire.c (revision b33a8d55775a3013157d6b0e3602c1fe178b48a6)
1 /*	$OpenBSD: check_expire.c,v 1.11 2015/03/15 00:41:27 millert Exp $	*/
2 
3 /*
4  * Copyright (c) 1997 Berkeley Software Design, Inc. All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by Berkeley Software Design,
17  *	Inc.
18  * 4. The name of Berkeley Software Design, Inc.  may not be used to endorse
19  *    or promote products derived from this software without specific prior
20  *    written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN, INC. ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN, INC. BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	BSDI $From: check_expire.c,v 2.1 1997/08/08 18:38:25 prb Exp $
35  */
36 
37 #include <sys/types.h>
38 
39 #include <errno.h>
40 #include <fcntl.h>
41 #include <pwd.h>
42 #include <signal.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <syslog.h>
47 #include <time.h>
48 #include <login_cap.h>
49 #include <bsd_auth.h>
50 
51 #include "util.h"
52 
53 static char *pwd_update(const struct passwd *, const struct passwd *);
54 
55 #define SECSPERDAY	(24 * 60 * 60)
56 #define TWOWEEKS	(2 * 7 * SECSPERDAY)
57 
58 int
59 login_check_expire(FILE *back, struct passwd *pwd, char *class, int lastchance)
60 {
61 	auth_session_t *as;
62 	login_cap_t *lc;
63 	quad_t dead, expire, warn;
64 	char *p;
65 
66 	if ((as = auth_open()) == NULL) {
67 		syslog(LOG_ERR, "failed to create auth session");
68 		return (1);
69 	}
70 	if (auth_setpwd(as, pwd) < 0) {
71 		syslog(LOG_ERR, "failed to set pwd entry in auth session");
72 		return (1);
73 	}
74 
75 	expire = auth_check_change(as);
76 	auth_close(as);
77 
78 	if (expire != 0) {
79 		fprintf(back, BI_VALUE " expire %qd\n", expire);
80 
81 		if (class == NULL)
82 			class = pwd->pw_class;
83 
84 		if ((lc = login_getclass(class)) == NULL) {
85 			dead = 0;
86 			warn = 0;
87 		} else {
88 			dead = login_getcaptime(lc, "password-dead", 0, 0);
89 			warn = login_getcaptime(lc, "password-warn",
90 			    TWOWEEKS, TWOWEEKS);
91 			if (dead < 0) {
92 				syslog(LOG_ERR, "class %s password-dead is %qd",
93 					lc->lc_class, dead);
94 				dead = 0;
95 			}
96 			if (warn < 0) {
97 				syslog(LOG_ERR, "class %s password-warn is %qd",
98 					lc->lc_class, warn);
99 				warn = 0;
100 			}
101 		}
102 		login_close(lc);
103 
104 		/*
105 		 * If their password is dead (expired longer than
106 		 * password-dead) then just reject them.  If it is
107 		 * expired but not dead yet, reject them with a
108 		 * PWEXPIRED so login knows they can still sort of
109 		 * get in.
110 		 */
111 		if (expire < -dead) {
112 			syslog(LOG_WARNING, "%s: dead password", pwd->pw_name);
113 			fprintf(back, BI_VALUE
114 			    " errormsg Your password has expired\n");
115 			fprintf(back, BI_REJECT "\n");
116 			return (1);
117 		}
118 		if (expire < 0) {
119 			if (lastchance) {
120 				struct passwd *npwd;
121 
122 				endpwent();
123 
124 				/*
125 				 * Only let them play this game once.
126 				 * Set their password change time to 1.
127 				 * This will most certainly cause any
128 				 * expired password to be dead, as well.
129 				 */
130 				npwd = pw_dup(pwd);
131 				npwd->pw_change = 1;
132 				p = pwd_update(npwd, pwd);
133 				explicit_bzero(npwd->pw_passwd,
134 				    strlen(npwd->pw_passwd));
135 				free(npwd);
136 				if (p != NULL) {
137 					fprintf(back, BI_VALUE " errormsg %s",
138 					    auth_mkvalue(p));
139 					fprintf(back, BI_REJECT "\n");
140 					return (1);
141 				}
142 			}
143 			syslog(LOG_WARNING, "%s: expired password", pwd->pw_name);
144 			fprintf(back, BI_VALUE
145 			    " errormsg Your password has expired\n");
146 			fprintf(back, BI_PWEXPIRED "\n");
147 			return (1);
148 		}
149 
150 		/*
151 		 * If their password is not expired but is about to expire
152 		 * then warn them.
153 		 */
154 		if (expire <= warn) {
155 			fprintf(back, BI_VALUE
156 			    " warnmsg Your password expires on %s\n",
157 			    ctime(&pwd->pw_change));
158 		}
159 	}
160 	return (0);
161 }
162 
163 static char *
164 pwd_update(const struct passwd *pwd, const struct passwd *opwd)
165 {
166 	int tfd, pfd;
167 
168 	pw_init();
169 	tfd = pw_lock(0);
170 	if (tfd < 0) {
171 		if (errno == EEXIST)
172 			return("the passwd file is busy.");
173 		else
174 			return("can't open passwd temp file");
175 	}
176 
177 	pfd = open(_PATH_MASTERPASSWD, O_RDONLY|O_CLOEXEC, 0);
178 	if (pfd < 0) {
179 		pw_abort();
180 		return(strerror(errno));
181 	}
182 
183 	pw_copy(pfd, tfd, pwd, opwd);
184 	if (pw_mkdb(pwd->pw_name, 0) < 0) {
185 		pw_abort();
186 		return("unable to update password database");
187 	}
188 
189 	return(NULL);
190 }
191