openpam_restore_cred.c revision 174832 
1/*-
2 * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
3 * Copyright (c) 2004-2007 Dag-Erling Sm��rgrav
4 * All rights reserved.
5 *
6 * This software was developed for the FreeBSD Project by ThinkSec AS and
7 * Network Associates Laboratories, the Security Research Division of
8 * Network Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
9 * ("CBOSS"), as part of the DARPA CHATS research program.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. The name of the author may not be used to endorse or promote
20 *    products derived from this software without specific prior written
21 *    permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 * $Id: openpam_restore_cred.c 408 2007-12-21 11:36:24Z des $
36 */
37
38#include <sys/param.h>
39
40#include <grp.h>
41#include <limits.h>
42#include <pwd.h>
43#include <stdlib.h>
44#include <unistd.h>
45
46#include <security/pam_appl.h>
47
48#include "openpam_impl.h"
49
50/*
51 * OpenPAM extension
52 *
53 * Restore credentials
54 */
55
56int
57openpam_restore_cred(pam_handle_t *pamh)
58{
59	const struct pam_saved_cred *scred;
60	const void *scredp;
61	int r;
62
63	ENTER();
64	r = pam_get_data(pamh, PAM_SAVED_CRED, &scredp);
65	if (r != PAM_SUCCESS)
66		RETURNC(r);
67	if (scredp == NULL)
68		RETURNC(PAM_SYSTEM_ERR);
69	scred = scredp;
70	if (scred->euid != geteuid()) {
71		if (seteuid(scred->euid) < 0 ||
72		    setgroups(scred->ngroups, scred->groups) < 0 ||
73		    setegid(scred->egid) < 0)
74			RETURNC(PAM_SYSTEM_ERR);
75	}
76	pam_set_data(pamh, PAM_SAVED_CRED, NULL, NULL);
77	RETURNC(PAM_SUCCESS);
78}
79
80/*
81 * Error codes:
82 *
83 *	=pam_get_data
84 *	PAM_SYSTEM_ERR
85 */
86
87/**
88 * The =openpam_restore_cred function restores the credentials saved by
89 * =openpam_borrow_cred.
90 *
91 * >setegid 2
92 * >seteuid 2
93 * >setgroups 2
94 */
95