pam_group.c revision 110653 
1/*-
2 * Copyright (c) 2003 Networks Associates Technology, Inc.
3 * All rights reserved.
4 *
5 * Portions of this software were developed for the FreeBSD Project by
6 * ThinkSec AS and NAI Labs, the Security Research Division of Network
7 * Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
8 * ("CBOSS"), as part of the DARPA CHATS research program.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. The name of the author may not be used to endorse or promote
19 *    products derived from this software without specific prior written
20 *    permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 THE AUTHOR OR CONTRIBUTORS 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
35#include <sys/cdefs.h>
36__FBSDID("$FreeBSD: head/lib/libpam/modules/pam_group/pam_group.c 110653 2003-02-10 18:59:20Z des $");
37
38#include <sys/types.h>
39
40#include <grp.h>
41#include <pwd.h>
42#include <stdarg.h>
43#include <stdio.h>
44#include <string.h>
45#include <syslog.h>
46#include <unistd.h>
47
48#define PAM_SM_AUTH
49
50#include <security/pam_appl.h>
51#include <security/pam_modules.h>
52#include <security/openpam.h>
53
54
55PAM_EXTERN int
56pam_sm_authenticate(pam_handle_t *pamh, int flags __unused,
57    int argc __unused, const char *argv[] __unused)
58{
59	const char *group, *user, *ruser;
60	char *const *list;
61	struct passwd *pwd;
62	struct group *grp;
63
64	/* get target account */
65	if (pam_get_user(pamh, &user, NULL) != PAM_SUCCESS ||
66	    user == NULL || (pwd = getpwnam(user)) == NULL)
67		return (PAM_AUTH_ERR);
68	if (pwd->pw_uid != 0 && openpam_get_option(pamh, "root_only"))
69		return (PAM_IGNORE);
70
71	/* get applicant */
72	if (pam_get_item(pamh, PAM_RUSER, (const void **)&ruser) != PAM_SUCCESS
73	    || ruser == NULL || (pwd = getpwnam(ruser)) == NULL)
74		return (PAM_AUTH_ERR);
75
76	/* get regulating group */
77	if ((group = openpam_get_option(pamh, "group")) == NULL)
78		group = "wheel";
79	if ((grp = getgrnam(group)) == NULL || grp->gr_mem == NULL)
80		goto failed;
81
82	/* check if the group is empty */
83	if (*grp->gr_mem == NULL)
84		goto failed;
85
86	/* check membership */
87	if (pwd->pw_gid == grp->gr_gid)
88		goto found;
89	for (list = grp->gr_mem; *list != NULL; ++list)
90		if (strcmp(*list, pwd->pw_name) == 0)
91			goto found;
92
93 not_found:
94	if (openpam_get_option(pamh, "deny"))
95		return (PAM_SUCCESS);
96	return (PAM_AUTH_ERR);
97 found:
98	if (openpam_get_option(pamh, "deny"))
99		return (PAM_AUTH_ERR);
100	return (PAM_SUCCESS);
101 failed:
102	if (openpam_get_option(pamh, "fail_safe"))
103		goto found;
104	else
105		goto not_found;
106}
107
108PAM_EXTERN int
109pam_sm_setcred(pam_handle_t * pamh __unused, int flags __unused,
110    int argc __unused, const char *argv[] __unused)
111{
112
113	return (PAM_SUCCESS);
114}
115
116PAM_MODULE_ENTRY("pam_group");
117