xref: /freebsd/contrib/openpam/lib/libpam/openpam_load.c (revision 02e9120893770924227138ba49df1edb3896112a)
1 /*-
2  * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
3  * Copyright (c) 2004-2013 Dag-Erling Smørgrav
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 
36 #ifdef HAVE_CONFIG_H
37 # include "config.h"
38 #endif
39 
40 #include <dlfcn.h>
41 #include <stdlib.h>
42 #include <string.h>
43 
44 #include <security/pam_appl.h>
45 
46 #include "openpam_impl.h"
47 
48 /*
49  * Locate a matching dynamic or static module.
50  */
51 
52 pam_module_t *
53 openpam_load_module(const char *modulename)
54 {
55 	pam_module_t *module;
56 
57 	module = openpam_dynamic(modulename);
58 	openpam_log(PAM_LOG_DEBUG, "%s dynamic %s",
59 	    (module == NULL) ? "no" : "using", modulename);
60 
61 #ifdef OPENPAM_STATIC_MODULES
62 	/* look for a static module */
63 	if (module == NULL && strchr(modulename, '/') == NULL) {
64 		module = openpam_static(modulename);
65 		openpam_log(PAM_LOG_DEBUG, "%s static %s",
66 		    (module == NULL) ? "no" : "using", modulename);
67 	}
68 #endif
69 	if (module == NULL) {
70 		openpam_log(PAM_LOG_ERROR, "no %s found", modulename);
71 		return (NULL);
72 	}
73 	return (module);
74 }
75 
76 
77 /*
78  * Release a module.
79  * XXX highly thread-unsafe
80  */
81 
82 static void
83 openpam_release_module(pam_module_t *module)
84 {
85 
86 	if (module == NULL)
87 		return;
88 	if (module->dlh == NULL)
89 		/* static module */
90 		return;
91 	dlclose(module->dlh);
92 	openpam_log(PAM_LOG_DEBUG, "releasing %s", module->path);
93 	FREE(module->path);
94 	FREE(module);
95 }
96 
97 
98 /*
99  * Destroy a chain, freeing all its links and releasing the modules
100  * they point to.
101  */
102 
103 static void
104 openpam_destroy_chain(pam_chain_t *chain)
105 {
106 
107 	if (chain == NULL)
108 		return;
109 	openpam_destroy_chain(chain->next);
110 	chain->next = NULL;
111 	FREEV(chain->optc, chain->optv);
112 	openpam_release_module(chain->module);
113 	chain->module = NULL;
114 	FREE(chain);
115 }
116 
117 
118 /*
119  * Clear the chains and release the modules
120  */
121 
122 void
123 openpam_clear_chains(pam_chain_t *policy[])
124 {
125 	int i;
126 
127 	for (i = 0; i < PAM_NUM_FACILITIES; ++i) {
128 		openpam_destroy_chain(policy[i]);
129 		policy[i] = NULL;
130 	}
131 }
132 
133 /*
134  * NOPARSE
135  */
136