1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2002 Networks Associates Technologies, Inc.
5 * All rights reserved.
6 *
7 * This software was developed for the FreeBSD Project by ThinkSec AS and
8 * NAI Labs, the Security Research Division of Network Associates, Inc.
9 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
10 * 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. The name of the author may not be used to endorse or promote
21 *    products derived from this software without specific prior written
22 *    permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#include <sys/param.h>
38
39#include <err.h>
40#include <pwd.h>
41#include <stdio.h>
42#include <stdlib.h>
43#include <syslog.h>
44#include <unistd.h>
45
46#include <security/pam_appl.h>
47#include <security/openpam.h>
48
49static pam_handle_t *pamh;
50static struct pam_conv pamc = {
51	openpam_ttyconv,
52	NULL
53};
54
55static char	*yp_domain;
56static char	*yp_host;
57
58static void
59usage(void)
60{
61	fprintf(stderr, "usage: passwd [-ly] [-d domain] [-h host] [user]\n");
62	exit(1);
63}
64
65int
66main(int argc, char *argv[])
67{
68	char hostname[MAXHOSTNAMELEN];
69	struct passwd *pwd = NULL; /* Keep compiler happy. */
70	int o, pam_err;
71	uid_t uid;
72
73	while ((o = getopt(argc, argv, "d:h:loy")) != -1)
74		switch (o) {
75		case 'd':
76			yp_domain = optarg;
77			break;
78		case 'h':
79			yp_host = optarg;
80			break;
81		case 'l':
82		case 'o':
83		case 'y':
84			/* compatibility */
85			break;
86		default:
87			usage();
88		}
89
90	argc -= optind;
91	argv += optind;
92
93	uid = getuid();
94
95	switch (argc) {
96	case 0:
97		if ((pwd = getpwuid(uid)) == NULL)
98			errx(1, "who are you?");
99		break;
100	case 1:
101		if ((pwd = getpwnam(*argv)) == NULL)
102			errx(1, "%s: no such user", *argv);
103		break;
104	default:
105		usage();
106	}
107
108	if (uid != 0 && uid != pwd->pw_uid)
109		errx(1, "permission denied");
110
111	/* check where the user's from */
112	switch (pwd->pw_fields & _PWF_SOURCE) {
113	case _PWF_FILES:
114		fprintf(stderr, "Changing local password for %s\n",
115		    pwd->pw_name);
116		break;
117	case _PWF_NIS:
118		fprintf(stderr, "Changing NIS password for %s\n",
119		    pwd->pw_name);
120		break;
121	default:
122		/* XXX: Green men ought to be supported via PAM. */
123		errx(1,
124	  "Sorry, `passwd' can only change passwords for local or NIS users.");
125	}
126
127#define pam_check(func) do { \
128	if (pam_err != PAM_SUCCESS) { \
129		if (pam_err == PAM_AUTH_ERR || pam_err == PAM_PERM_DENIED || \
130		    pam_err == PAM_AUTHTOK_RECOVERY_ERR) \
131			warnx("sorry"); \
132		else \
133			warnx("%s(): %s", func, pam_strerror(pamh, pam_err)); \
134		goto end; \
135	} \
136} while (0)
137
138	/* initialize PAM */
139	pam_err = pam_start("passwd", pwd->pw_name, &pamc, &pamh);
140	pam_check("pam_start");
141
142	pam_err = pam_set_item(pamh, PAM_TTY, ttyname(STDERR_FILENO));
143	pam_check("pam_set_item");
144	gethostname(hostname, sizeof hostname);
145	pam_err = pam_set_item(pamh, PAM_RHOST, hostname);
146	pam_check("pam_set_item");
147	pam_err = pam_set_item(pamh, PAM_RUSER, getlogin());
148	pam_check("pam_set_item");
149
150	/* set YP domain and host */
151	pam_err = pam_set_data(pamh, "yp_domain", yp_domain, NULL);
152	pam_check("pam_set_data");
153	pam_err = pam_set_data(pamh, "yp_server", yp_host, NULL);
154	pam_check("pam_set_data");
155
156	/* set new password */
157	pam_err = pam_chauthtok(pamh, 0);
158	pam_check("pam_chauthtok");
159
160 end:
161	pam_end(pamh, pam_err);
162	exit(pam_err == PAM_SUCCESS ? 0 : 1);
163}
164