contrib/openpam/lib/openpam_dynamic.c

   1 /*-
   2  * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
   3  * Copyright (c) 2004-2007 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  * $Id: openpam_dynamic.c 408 2007-12-21 11:36:24Z des $
  36  */
  37
  38 #include <dlfcn.h>
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42
  43 #include <security/pam_appl.h>
  44
  45 #include "openpam_impl.h"
  46
  47 #ifndef RTLD_NOW
  48 #define RTLD_NOW RTLD_LAZY
  49 #endif
  50
  51 /*
  52  * OpenPAM internal
  53  *
  54  * Locate a dynamically linked module
  55  */
  56
  57 pam_module_t *
  58 openpam_dynamic(const char *path)
  59 {
  60         pam_module_t *module;
  61         const char *prefix;
  62         char *vpath;
  63         void *dlh;
  64         int i;
  65
  66         dlh = NULL;
  67         if ((module = calloc(1, sizeof *module)) == NULL)
  68                 goto buf_err;
  69
  70         /* Prepend the standard prefix if not an absolute pathname. */
  71         if (path[0] != '/')
  72                 prefix = OPENPAM_MODULES_DIR;
  73         else
  74                 prefix = "";
  75
  76         /* try versioned module first, then unversioned module */
  77         if (asprintf(&vpath, "%s%s.%d", prefix, path, LIB_MAJ) < 0)
  78                 goto buf_err;
  79         if ((dlh = dlopen(vpath, RTLD_NOW)) == NULL) {
  80                 openpam_log(PAM_LOG_DEBUG, "%s: %s", vpath, dlerror());
  81                 *strrchr(vpath, '.') = '\0';
  82                 if ((dlh = dlopen(vpath, RTLD_NOW)) == NULL) {
  83                         openpam_log(PAM_LOG_DEBUG, "%s: %s", vpath, dlerror());
  84                         FREE(vpath);
  85                         FREE(module);
  86                         return (NULL);
  87                 }
  88         }
  89         FREE(vpath);
  90         if ((module->path = strdup(path)) == NULL)
  91                 goto buf_err;
  92         module->dlh = dlh;
  93         for (i = 0; i < PAM_NUM_PRIMITIVES; ++i) {
  94                 module->func[i] = (pam_func_t)dlsym(dlh, _pam_sm_func_name[i]);
  95                 if (module->func[i] == NULL)
  96                         openpam_log(PAM_LOG_DEBUG, "%s: %s(): %s",
  97                             path, _pam_sm_func_name[i], dlerror());
  98         }
  99         return (module);
 100  buf_err:
 101         openpam_log(PAM_LOG_ERROR, "%m");
 102         if (dlh != NULL)
 103                 dlclose(dlh);
 104         FREE(module);
 105         return (NULL);
 106 }
 107
 108 /*
 109  * NOPARSE
 110  */