openpam_load.c revision 348980 
1/*-
2 * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
3 * Copyright (c) 2004-2013 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 * $OpenPAM: openpam_load.c 938 2017-04-30 21:34:42Z des $
36 */
37
38#ifdef HAVE_CONFIG_H
39# include "config.h"
40#endif
41
42#include <dlfcn.h>
43#include <stdlib.h>
44#include <string.h>
45
46#include <security/pam_appl.h>
47
48#include "openpam_impl.h"
49
50/*
51 * Locate a matching dynamic or static module.
52 */
53
54pam_module_t *
55openpam_load_module(const char *modulename)
56{
57	pam_module_t *module;
58
59	module = openpam_dynamic(modulename);
60	openpam_log(PAM_LOG_DEBUG, "%s dynamic %s",
61	    (module == NULL) ? "no" : "using", modulename);
62
63#ifdef OPENPAM_STATIC_MODULES
64	/* look for a static module */
65	if (module == NULL && strchr(modulename, '/') == NULL) {
66		module = openpam_static(modulename);
67		openpam_log(PAM_LOG_DEBUG, "%s static %s",
68		    (module == NULL) ? "no" : "using", modulename);
69	}
70#endif
71	if (module == NULL) {
72		openpam_log(PAM_LOG_ERROR, "no %s found", modulename);
73		return (NULL);
74	}
75	return (module);
76}
77
78
79/*
80 * Release a module.
81 * XXX highly thread-unsafe
82 */
83
84static void
85openpam_release_module(pam_module_t *module)
86{
87
88	if (module == NULL)
89		return;
90	if (module->dlh == NULL)
91		/* static module */
92		return;
93	dlclose(module->dlh);
94	openpam_log(PAM_LOG_DEBUG, "releasing %s", module->path);
95	FREE(module->path);
96	FREE(module);
97}
98
99
100/*
101 * Destroy a chain, freeing all its links and releasing the modules
102 * they point to.
103 */
104
105static void
106openpam_destroy_chain(pam_chain_t *chain)
107{
108
109	if (chain == NULL)
110		return;
111	openpam_destroy_chain(chain->next);
112	chain->next = NULL;
113	FREEV(chain->optc, chain->optv);
114	openpam_release_module(chain->module);
115	chain->module = NULL;
116	FREE(chain);
117}
118
119
120/*
121 * Clear the chains and release the modules
122 */
123
124void
125openpam_clear_chains(pam_chain_t *policy[])
126{
127	int i;
128
129	for (i = 0; i < PAM_NUM_FACILITIES; ++i) {
130		openpam_destroy_chain(policy[i]);
131		policy[i] = NULL;
132	}
133}
134
135/*
136 * NOPARSE
137 */
138