library/log_validation.php

   1 <?php
   2 /**
   3  * library/log_validation.php to validate audit logs tamper resistance.
   4  *
   5  * Copyright (C) 2016 Visolve <services@visolve.com>
   6  *
   7  * LICENSE: This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * as published by the Free Software Foundation; either version 3
  10  * of the License, or (at your option) any later version.
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU General Public License for more details.
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program. If not, see <http://opensource.org/licenses/gpl-license.php>;.
  17  *
  18  * @package OpenEMR
  19  * @author  Visolve <services@visolve.com>
  20  * @link    http://www.open-emr.org
  21  */
  22
  23 $fake_register_globals=false;
  24
  25
  26 require_once("../interface/globals.php");
  27 require_once("$srcdir/log.inc");
  28
  29
  30         $valid  = true;
  31         $errors = array();
  32         catch_logs();
  33         $sql = sqlStatement("select * from log_validator");
  34         while($row = sqlFetchArray($sql)){
  35                 $logEntry = sqlQuery("select * from log where id = ?",array($row['log_id']));
  36                 if(empty($logEntry)){
  37                         $valid = false;
  38                         array_push($errors, xl("Following audit log entry number is missing") . ": " . $row['log_id']);
  39                 }
  40                 else if($row['log_checksum'] != $logEntry['checksum']){
  41                         $valid = false;
  42                         array_push($errors, xl("Audit log tampering evident at entry number") . " " . $row['log_id']);
  43                 }
  44                 if(!$valid) break;
  45         }
  46         if($valid){
  47                 echo xl("Audit Log Validated Successfully");
  48         }
  49         else
  50         {
  51                 echo xl("Audit Log Validation Failed") . "(ERROR:: $errors[0])";
  52         }
  53
  54         function catch_logs(){
  55                 $sql  = sqlStatement("select * from log where id not in(select log_id from log_validator) and checksum is NOT null and checksum != ''");
  56                 while($row = sqlFetchArray($sql)){
  57                         sqlInsert("INSERT into log_validator (log_id,log_checksum) VALUES(?,?)",array($row['id'],$row['checksum']));
  58                 }
  59         }
  60 ?>