1 /* $OpenBSD: login_lchpass.c,v 1.21 2018/04/26 12:42:51 guenther Exp $ */
2
3 /*-
4 * Copyright (c) 1995,1996 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: login_lchpass.c,v 1.4 1997/08/08 18:58:23 prb Exp $
35 */
36
37 #include <sys/resource.h>
38 #include <sys/uio.h>
39
40 #include <pwd.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <syslog.h>
45 #include <unistd.h>
46 #include <login_cap.h>
47 #include <readpassphrase.h>
48
49 #define BACK_CHANNEL 3
50
51 int local_passwd(char *, int);
52
53 int
main(int argc,char * argv[])54 main(int argc, char *argv[])
55 {
56 struct iovec iov[2];
57 struct passwd *pwd;
58 char *username = NULL, *hash = NULL;
59 char oldpass[1024];
60 struct rlimit rl;
61 int c;
62
63 iov[0].iov_base = BI_SILENT;
64 iov[0].iov_len = sizeof(BI_SILENT) - 1;
65 iov[1].iov_base = "\n";
66 iov[1].iov_len = 1;
67
68 rl.rlim_cur = 0;
69 rl.rlim_max = 0;
70 (void)setrlimit(RLIMIT_CORE, &rl);
71
72 (void)setpriority(PRIO_PROCESS, 0, 0);
73
74 openlog("login", LOG_ODELAY, LOG_AUTH);
75
76 while ((c = getopt(argc, argv, "v:s:")) != -1)
77 switch (c) {
78 case 'v':
79 break;
80 case 's': /* service */
81 if (strcmp(optarg, "login") != 0) {
82 syslog(LOG_ERR, "%s: invalid service", optarg);
83 exit(1);
84 }
85 break;
86 default:
87 syslog(LOG_ERR, "usage error");
88 exit(1);
89 }
90
91 switch (argc - optind) {
92 case 2:
93 /* class is not used */
94 case 1:
95 username = argv[optind];
96 break;
97 default:
98 syslog(LOG_ERR, "usage error");
99 exit(1);
100 }
101
102 pwd = getpwnam_shadow(username);
103 if (pwd) {
104 if (pwd->pw_uid == 0) {
105 syslog(LOG_ERR, "attempted root password change");
106 pwd = NULL;
107 } else if (*pwd->pw_passwd == '\0') {
108 syslog(LOG_ERR, "%s attempting to add password",
109 username);
110 pwd = NULL;
111 }
112 }
113
114 if (pwd)
115 hash = pwd->pw_passwd;
116
117 (void)setpriority(PRIO_PROCESS, 0, -4);
118
119 (void)printf("Changing local password for %s.\n", username);
120 if ((readpassphrase("Old Password:", oldpass, sizeof(oldpass),
121 RPP_ECHO_OFF)) == NULL)
122 exit(1);
123
124 if (crypt_checkpass(oldpass, hash) != 0) {
125 explicit_bzero(oldpass, strlen(oldpass));
126 exit(1);
127 }
128 explicit_bzero(oldpass, strlen(oldpass));
129
130 /*
131 * We rely on local_passwd() to block signals during the
132 * critical section.
133 */
134 local_passwd(pwd->pw_name, 1);
135 (void)writev(BACK_CHANNEL, iov, 2);
136 exit(0);
137 }
138