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 $sanitize_all_escapes=true;
  25
  26 require_once("../interface/globals.php");
  27 require_once("$srcdir/log.inc");
  28 require_once("$srcdir/formatting.inc.php");
  29
  30
  31         $valid  = true;
  32         $errors = array();
  33         catch_logs();
  34         $sql = sqlStatement("select * from log_validator");
  35         while($row = sqlFetchArray($sql)){
  36                 $logEntry = sqlQuery("select * from log where id = ?",array($row['log_id']));
  37                 if(empty($logEntry)){
  38                         $valid = false;
  39                         array_push($errors, xl("Following audit log entry number is missing") . ": " . $row['log_id']);
  40                 }
  41                 else if($row['log_checksum'] != $logEntry['checksum']){
  42                         $valid = false;
  43                         array_push($errors, xl("Audit log tampering evident at entry number") . " " . $row['log_id']);
  44                 }
  45                 if(!$valid) break;
  46         }
  47         if($valid){
  48                 echo xl("Audit Log Validated Successfully");
  49         }
  50         else
  51         {
  52                 echo xl("Audit Log Validation Failed") . "(ERROR:: $errors[0])";
  53         }
  54
  55         function catch_logs(){
  56                 $sql  = sqlStatement("select * from log where id not in(select log_id from log_validator) and checksum is NOT null and checksum != ''");
  57                 while($row = sqlFetchArray($sql)){
  58                         sqlInsert("INSERT into log_validator (log_id,log_checksum) VALUES(?,?)",array($row['id'],$row['checksum']));
  59                 }
  60         }
  61 ?>