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      1 /*	$NetBSD: openpam_load.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) 2004-2013 Dag-Erling Smrgrav
      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_load.c,v 1.4 2023/06/30 21:46:20 christos Exp $");
     44 
     45 #include <dlfcn.h>
     46 #include <stdlib.h>
     47 #include <string.h>
     48 
     49 #include <security/pam_appl.h>
     50 
     51 #include "openpam_impl.h"
     52 
     53 /*
     54  * Locate a matching dynamic or static module.
     55  */
     56 
     57 pam_module_t *
     58 openpam_load_module(const char *modulename)
     59 {
     60 	pam_module_t *module;
     61 
     62 	module = openpam_dynamic(modulename);
     63 	openpam_log(PAM_LOG_DEBUG, "%s dynamic %s",
     64 	    (module == NULL) ? "no" : "using", modulename);
     65 
     66 #ifdef OPENPAM_STATIC_MODULES
     67 	/* look for a static module */
     68 	if (module == NULL && strchr(modulename, '/') == NULL) {
     69 		module = openpam_static(modulename);
     70 		openpam_log(PAM_LOG_DEBUG, "%s static %s",
     71 		    (module == NULL) ? "no" : "using", modulename);
     72 	}
     73 #endif
     74 	if (module == NULL) {
     75 		openpam_log(PAM_LOG_ERROR, "no %s found", modulename);
     76 		return (NULL);
     77 	}
     78 	return (module);
     79 }
     80 
     81 
     82 /*
     83  * Release a module.
     84  * XXX highly thread-unsafe
     85  */
     86 
     87 static void
     88 openpam_release_module(pam_module_t *module)
     89 {
     90 
     91 	if (module == NULL)
     92 		return;
     93 	if (module->dlh == NULL)
     94 		/* static module */
     95 		return;
     96 	dlclose(module->dlh);
     97 	openpam_log(PAM_LOG_DEBUG, "releasing %s", module->path);
     98 	FREE(module->path);
     99 	FREE(module);
    100 }
    101 
    102 
    103 /*
    104  * Destroy a chain, freeing all its links and releasing the modules
    105  * they point to.
    106  */
    107 
    108 static void
    109 openpam_destroy_chain(pam_chain_t *chain)
    110 {
    111 
    112 	if (chain == NULL)
    113 		return;
    114 	openpam_destroy_chain(chain->next);
    115 	chain->next = NULL;
    116 	FREEV(chain->optc, chain->optv);
    117 	openpam_release_module(chain->module);
    118 	chain->module = NULL;
    119 	FREE(chain);
    120 }
    121 
    122 
    123 /*
    124  * Clear the chains and release the modules
    125  */
    126 
    127 void
    128 openpam_clear_chains(pam_chain_t *policy[])
    129 {
    130 	int i;
    131 
    132 	for (i = 0; i < PAM_NUM_FACILITIES; ++i) {
    133 		openpam_destroy_chain(policy[i]);
    134 		policy[i] = NULL;
    135 	}
    136 }
    137 
    138 /*
    139  * NOPARSE
    140  */
    141