1  /*
       2   * Copyright (c) 2022 Iker Pedrosa <ipedrosa@redhat.com>
       3   *
       4   * Redistribution and use in source and binary forms, with or without
       5   * modification, are permitted provided that the following conditions
       6   * are met:
       7   * 1. Redistributions of source code must retain the above copyright
       8   *    notice, and the entire permission notice in its entirety,
       9   *    including the disclaimer of warranties.
      10   * 2. Redistributions in binary form must reproduce the above copyright
      11   *    notice, this list of conditions and the following disclaimer in the
      12   *    documentation and/or other materials provided with the distribution.
      13   * 3. The name of the author may not be used to endorse or promote
      14   *    products derived from this software without specific prior
      15   *    written permission.
      16   *
      17   * ALTERNATIVELY, this product may be distributed under the terms of
      18   * the GNU Public License, in which case the provisions of the GPL are
      19   * required INSTEAD OF the above restrictions.  (This clause is
      20   * necessary due to a potential bad interaction between the GPL and
      21   * the restrictions contained in a BSD-style copyright.)
      22   *
      23   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
      24   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
      25   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
      26   * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
      27   * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
      28   * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
      29   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
      30   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
      31   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
      32   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
      33   * OF THE POSSIBILITY OF SUCH DAMAGE.
      34   */
      35  
      36  #include "config.h"
      37  
      38  #include <stdio.h>
      39  #include <stdlib.h>
      40  #include <string.h>
      41  #include <syslog.h>
      42  #include <sys/stat.h>
      43  
      44  #include <security/pam_modutil.h>
      45  
      46  #include "pam_inline.h"
      47  #include "pwhistory_config.h"
      48  
      49  #define PWHISTORY_DEFAULT_CONF SCONFIGDIR "/pwhistory.conf"
      50  
      51  #ifdef VENDOR_SCONFIGDIR
      52  #define VENDOR_PWHISTORY_DEFAULT_CONF (VENDOR_SCONFIGDIR "/pwhistory.conf")
      53  #endif
      54  
      55  void
      56  parse_config_file(pam_handle_t *pamh, int argc, const char **argv,
      57                    struct options_t *options)
      58  {
      59      const char *fname = NULL;
      60      int i;
      61      char *val;
      62  
      63      for (i = 0; i < argc; ++i) {
      64          const char *str = pam_str_skip_prefix(argv[i], "conf=");
      65  
      66          if (str != NULL) {
      67              fname = str;
      68          }
      69      }
      70  
      71      if (fname == NULL) {
      72          fname = PWHISTORY_DEFAULT_CONF;
      73  
      74  #ifdef VENDOR_PWHISTORY_DEFAULT_CONF
      75          /*
      76           * Check whether PWHISTORY_DEFAULT_CONF file is available.
      77           * If it does not exist, fall back to VENDOR_PWHISTORY_DEFAULT_CONF file.
      78           */
      79          struct stat buffer;
      80          if (stat(fname, &buffer) != 0 && errno == ENOENT) {
      81              fname = VENDOR_PWHISTORY_DEFAULT_CONF;
      82          }
      83  #endif
      84      }
      85  
      86      val = pam_modutil_search_key (pamh, fname, "debug");
      87      if (val != NULL) {
      88          options->debug = 1;
      89          free(val);
      90      }
      91  
      92      val = pam_modutil_search_key (pamh, fname, "enforce_for_root");
      93      if (val != NULL) {
      94          options->enforce_for_root = 1;
      95          free(val);
      96      }
      97  
      98      val = pam_modutil_search_key (pamh, fname, "remember");
      99      if (val != NULL) {
     100          unsigned int temp;
     101          if (sscanf(val, "%u", &temp) != 1) {
     102              pam_syslog(pamh, LOG_ERR,
     103                  "Bad number supplied for remember argument");
     104          } else {
     105              options->remember = temp;
     106          }
     107          free(val);
     108      }
     109  
     110      val = pam_modutil_search_key (pamh, fname, "retry");
     111      if (val != NULL) {
     112          unsigned int temp;
     113          if (sscanf(val, "%u", &temp) != 1) {
     114              pam_syslog(pamh, LOG_ERR,
     115                  "Bad number supplied for retry argument");
     116          } else {
     117              options->tries = temp;
     118          }
     119          free(val);
     120      }
     121  
     122      val = pam_modutil_search_key (pamh, fname, "file");
     123      if (val != NULL) {
     124          if (*val != '/') {
     125              pam_syslog (pamh, LOG_ERR,
     126                  "File path should be absolute: %s", val);
     127          } else {
     128              options->filename = val;
     129          }
     130      }
     131  }