xref: /freebsd/lib/libpam/modules/pam_rhosts/pam_rhosts.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2002 Danny Braniss
5  * All rights reserved.
6  * Copyright (c) 2001,2002 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. The name of the author may not be used to endorse or promote
23  *    products derived from this software without specific prior written
24  *    permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  */
38 
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 #include <pwd.h>
43 #include <stddef.h>
44 #include <string.h>
45 #include <unistd.h>
46 
47 #define PAM_SM_AUTH
48 #include <security/pam_appl.h>
49 #include <security/pam_modules.h>
50 #include <security/pam_mod_misc.h>
51 
52 #define OPT_ALLOW_ROOT "allow_root"
53 
54 PAM_EXTERN int
55 pam_sm_authenticate(pam_handle_t *pamh, int flags __unused,
56     int argc __unused, const char *argv[] __unused)
57 {
58 	struct passwd *pw;
59 	const char *user;
60 	const void *ruser, *rhost;
61 	int err, superuser;
62 
63 	err = pam_get_user(pamh, &user, NULL);
64 	if (err != PAM_SUCCESS)
65 		return (err);
66 
67 	if ((pw = getpwnam(user)) == NULL)
68 		return (PAM_USER_UNKNOWN);
69 	if (pw->pw_uid == 0 &&
70 	    openpam_get_option(pamh, OPT_ALLOW_ROOT) == NULL)
71 		return (PAM_AUTH_ERR);
72 
73 	err = pam_get_item(pamh, PAM_RUSER, &ruser);
74 	if (err != PAM_SUCCESS)
75 		return (PAM_AUTH_ERR);
76 
77 	err = pam_get_item(pamh, PAM_RHOST, &rhost);
78 	if (err != PAM_SUCCESS)
79 		return (PAM_AUTH_ERR);
80 
81 	superuser = (strcmp(user, "root") == 0);
82 	err = ruserok(rhost, superuser, ruser, user);
83 	if (err != 0)
84 		return (PAM_AUTH_ERR);
85 
86 	return (PAM_SUCCESS);
87 }
88 
89 PAM_EXTERN int
90 pam_sm_setcred(pam_handle_t *pamh __unused, int flags __unused,
91     int argc __unused, const char *argv[] __unused)
92 {
93 
94 	return (PAM_SUCCESS);
95 }
96 
97 PAM_MODULE_ENTRY("pam_rhosts");
98