xref: /dflybsd-src/lib/libpam/modules/pam_self/pam_self.c (revision 242be47e2206d44451f1e1b27f7966e08c0620c8)
1*242be47eSzrj /*-
2*242be47eSzrj  * Copyright (c) 2001 Mark R V Murray
3*242be47eSzrj  * All rights reserved.
4*242be47eSzrj  * Copyright (c) 2001,2002 Networks Associates Technology, Inc.
5*242be47eSzrj  * All rights reserved.
6*242be47eSzrj  *
7*242be47eSzrj  * Portions of this software were developed for the FreeBSD Project by
8*242be47eSzrj  * ThinkSec AS and NAI Labs, the Security Research Division of Network
9*242be47eSzrj  * Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
10*242be47eSzrj  * ("CBOSS"), as part of the DARPA CHATS research program.
11*242be47eSzrj  *
12*242be47eSzrj  * Redistribution and use in source and binary forms, with or without
13*242be47eSzrj  * modification, are permitted provided that the following conditions
14*242be47eSzrj  * are met:
15*242be47eSzrj  * 1. Redistributions of source code must retain the above copyright
16*242be47eSzrj  *    notice, this list of conditions and the following disclaimer.
17*242be47eSzrj  * 2. Redistributions in binary form must reproduce the above copyright
18*242be47eSzrj  *    notice, this list of conditions and the following disclaimer in the
19*242be47eSzrj  *    documentation and/or other materials provided with the distribution.
20*242be47eSzrj  * 3. The name of the author may not be used to endorse or promote
21*242be47eSzrj  *    products derived from this software without specific prior written
22*242be47eSzrj  *    permission.
23*242be47eSzrj  *
24*242be47eSzrj  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
25*242be47eSzrj  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26*242be47eSzrj  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27*242be47eSzrj  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
28*242be47eSzrj  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29*242be47eSzrj  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30*242be47eSzrj  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31*242be47eSzrj  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32*242be47eSzrj  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33*242be47eSzrj  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34*242be47eSzrj  * SUCH DAMAGE.
35*242be47eSzrj  *
36*242be47eSzrj  * $FreeBSD: src/lib/libpam/modules/pam_self/pam_self.c,v 1.9 2002/04/12 22:27:24 des Exp $
37*242be47eSzrj  */
38*242be47eSzrj 
39*242be47eSzrj #define _BSD_SOURCE
40*242be47eSzrj 
41*242be47eSzrj #include <pwd.h>
42*242be47eSzrj #include <unistd.h>
43*242be47eSzrj #include <syslog.h>
44*242be47eSzrj 
45*242be47eSzrj #define PAM_SM_AUTH
46*242be47eSzrj 
47*242be47eSzrj #include <security/pam_appl.h>
48*242be47eSzrj #include <security/pam_modules.h>
49*242be47eSzrj #include <security/pam_mod_misc.h>
50*242be47eSzrj 
51*242be47eSzrj #define OPT_ALLOW_ROOT "allow_root"
52*242be47eSzrj 
53*242be47eSzrj PAM_EXTERN int
54*242be47eSzrj pam_sm_authenticate(pam_handle_t *pamh, int flags __unused,
55*242be47eSzrj 		    int argc __unused, const char *argv[] __unused)
56*242be47eSzrj {
57*242be47eSzrj 	struct passwd *pwd;
58*242be47eSzrj 	const char *luser;
59*242be47eSzrj 	int pam_err;
60*242be47eSzrj 	uid_t uid;
61*242be47eSzrj 
62*242be47eSzrj 	pam_err = pam_get_user(pamh, &luser, NULL);
63*242be47eSzrj 	if (pam_err != PAM_SUCCESS)
64*242be47eSzrj 		return (pam_err);
65*242be47eSzrj 	if (luser == NULL || (pwd = getpwnam(luser)) == NULL)
66*242be47eSzrj 		return (PAM_AUTH_ERR);
67*242be47eSzrj 
68*242be47eSzrj 	uid = getuid();
69*242be47eSzrj 	if (uid == 0 && !openpam_get_option(pamh, OPT_ALLOW_ROOT))
70*242be47eSzrj 		return (PAM_AUTH_ERR);
71*242be47eSzrj 
72*242be47eSzrj 	if (uid == (uid_t)pwd->pw_uid)
73*242be47eSzrj 		return (PAM_SUCCESS);
74*242be47eSzrj 
75*242be47eSzrj 	PAM_VERBOSE_ERROR("Refused; source and target users differ");
76*242be47eSzrj 
77*242be47eSzrj 	return (PAM_AUTH_ERR);
78*242be47eSzrj }
79*242be47eSzrj 
80*242be47eSzrj PAM_EXTERN int
81*242be47eSzrj pam_sm_setcred(pam_handle_t *pamh __unused, int flags __unused,
82*242be47eSzrj 	       int argc __unused, const char *argv[] __unused)
83*242be47eSzrj {
84*242be47eSzrj 
85*242be47eSzrj 	return (PAM_SUCCESS);
86*242be47eSzrj }
87*242be47eSzrj 
88*242be47eSzrj PAM_MODULE_ENTRY("pam_self");
89