1 /* $NetBSD: openpam_restore_cred.c,v 1.4 2023/06/30 21:46:20 christos Exp $ */
2
3 /*-
4 * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
5 * Copyright (c) 2004-2011 Dag-Erling Smørgrav
6 * All rights reserved.
7 *
8 * This software was developed for the FreeBSD Project by ThinkSec AS and
9 * Network Associates Laboratories, the Security Research Division of
10 * Network Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035
11 * ("CBOSS"), as part of the DARPA CHATS research program.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. The name of the author may not be used to endorse or promote
22 * products derived from this software without specific prior written
23 * permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 */
37
38 #ifdef HAVE_CONFIG_H
39 # include "config.h"
40 #endif
41
42 #include <sys/cdefs.h>
43 __RCSID("$NetBSD: openpam_restore_cred.c,v 1.4 2023/06/30 21:46:20 christos Exp $");
44
45 #include <sys/param.h>
46
47 #include <grp.h>
48 #include <limits.h>
49 #include <pwd.h>
50 #include <stdlib.h>
51 #include <unistd.h>
52
53 #include <security/pam_appl.h>
54
55 #include "openpam_impl.h"
56 #include "openpam_cred.h"
57
58 /*
59 * OpenPAM extension
60 *
61 * Restore credentials
62 */
63
64 int
openpam_restore_cred(pam_handle_t * pamh)65 openpam_restore_cred(pam_handle_t *pamh)
66 {
67 const struct pam_saved_cred *scred;
68 const void *scredp;
69 int r;
70
71 ENTER();
72 r = pam_get_data(pamh, PAM_SAVED_CRED, &scredp);
73 if (r != PAM_SUCCESS)
74 RETURNC(r);
75 if (scredp == NULL)
76 RETURNC(PAM_SYSTEM_ERR);
77 scred = scredp;
78 if (scred->euid != geteuid()) {
79 if (seteuid(scred->euid) < 0 ||
80 setgroups(scred->ngroups, scred->groups) < 0 ||
81 setegid(scred->egid) < 0)
82 RETURNC(PAM_SYSTEM_ERR);
83 }
84 pam_set_data(pamh, PAM_SAVED_CRED, NULL, NULL);
85 RETURNC(PAM_SUCCESS);
86 }
87
88 /*
89 * Error codes:
90 *
91 * =pam_get_data
92 * PAM_SYSTEM_ERR
93 */
94
95 /**
96 * The =openpam_restore_cred function restores the credentials saved by
97 * =openpam_borrow_cred.
98 *
99 * >setegid 2
100 * >seteuid 2
101 * >setgroups 2
102 */
103