library/sanitize.inc.php

   1 <?php
   2 /**
   3  * Function to check and/or sanitize things for security such as
   4  * directories names, file names, etc.
   5  * Also including csrf token management functions.
   6  *
   7  * @package   OpenEMR
   8  * @link      https://www.open-emr.org
   9  * @author    Brady Miller <brady.g.miller@gmail.com>
  10  * @author    Roberto Vasquez <robertogagliotta@gmail.com>
  11  * @author    Shachar Zilbershlag <shaharzi@matrix.co.il>
  12  * @copyright Copyright (c) 2012-2018 Brady Miller <brady.g.miller@gmail.com>
  13  * @license   https://github.com/openemr/openemr/blob/master/LICENSE GNU General Public License 3
  14  */
  15
  16 use OpenEMR\Common\Utils\RandomGenUtils;
  17
  18 // Function to collect ip address(es)
  19 function collectIpAddresses()
  20 {
  21     $mainIp = $_SERVER['REMOTE_ADDR'];
  22     $stringIp = $mainIp;
  23
  24     if (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) {
  25         $forwardIp = $_SERVER['HTTP_X_FORWARDED_FOR'];
  26         $stringIp .= " (" . $forwardIp . ")";
  27     }
  28
  29     return array(
  30         'ip_string' => $stringIp,
  31         'ip' => $mainIp,
  32         'forward_ip' => $forwardIp
  33     );
  34 }
  35
  36 // Function to create a csrf_token
  37 function createCsrfToken()
  38 {
  39     return RandomGenUtils::createUniqueToken();
  40 }
  41
  42 // Function to collect the csrf token
  43 function collectCsrfToken()
  44 {
  45     return $_SESSION['csrf_token'];
  46 }
  47
  48 // Function to verify a csrf_token
  49 function verifyCsrfToken($token)
  50 {
  51     if (empty(collectCsrfToken())) {
  52         error_log("OpenEMR Error : OpenEMR is potentially not secure because CSRF token was not formed correctly.");
  53         return false;
  54     } elseif (empty($token)) {
  55         return false;
  56     } elseif (collectCsrfToken() == $token) {
  57         return true;
  58     } else {
  59         return false;
  60     }
  61 }
  62
  63 function csrfNotVerified($toScreen = true, $toLog = true)
  64 {
  65     if ($toScreen) {
  66         echo xlt('Authentication Error');
  67     }
  68     if ($toLog) {
  69         error_log("OpenEMR CSRF token authentication error");
  70     }
  71     die;
  72 }
  73
  74 // Sanitize a json encoded entry.
  75 function json_sanitize($json)
  76 {
  77     if (json_decode($json)) {
  78         return json_encode(json_decode($json, true));
  79     } else {
  80         error_log("OPENEMR ERROR: " . $json . " is not a valid json ");
  81         return false;
  82     }
  83 }
  84
  85 // If the label contains any illegal characters, then the script will die.
  86 function check_file_dir_name($label)
  87 {
  88     if (empty($label) || preg_match('/[^A-Za-z0-9_.-]/', $label)) {
  89         error_log("ERROR: The following variable contains invalid characters:" . $label);
  90         die(xlt("ERROR: The following variable contains invalid characters").": ". attr($label));
  91     } else {
  92         return $label;
  93     }
  94 }
  95
  96 // Convert all illegal characters to _
  97 function convert_safe_file_dir_name($label)
  98 {
  99     return preg_replace('/[^A-Za-z0-9_.-]/', '_', $label);
 100 }
 101
 102 // Convert all non A-Z a-z 0-9 characters to _
 103 function convert_very_strict_label($label)
 104 {
 105     return preg_replace('/[^A-Za-z0-9]/', '_', $label);
 106 }
 107
 108 //Basename functionality for nonenglish languages (without this, basename function omits nonenglish characters).
 109 function basename_international($path)
 110 {
 111     $parts = preg_split('~[\\\\/]~', $path);
 112     foreach ($parts as $key => $value) {
 113         $encoded = urlencode($value);
 114         $parts[$key] = $encoded;
 115     }
 116
 117     $encoded_path = implode("/", $parts);
 118     $encoded_file_name = basename($encoded_path);
 119     $decoded_file_name = urldecode($encoded_file_name);
 120
 121     return $decoded_file_name;
 122 }
 123
 124
 125 /**
 126  * This function detects a MIME type for a file and check if it in the white list of the allowed mime types.
 127  * @param string $file - file location.
 128  * @param array|null $whiteList - array of mime types that allowed to upload.
 129  */
 130 // Regarding the variable below. In the case of multiple file upload the isWhiteList function will run multiple
 131 // times, therefore, storing the white list in the variable below to prevent multiple requests from database.
 132 $white_list = null;
 133 function isWhiteFile($file)
 134 {
 135     global $white_list;
 136     if (is_null($white_list)) {
 137         $white_list = array();
 138         $lres = sqlStatement("SELECT option_id FROM list_options WHERE list_id = 'files_white_list' AND activity = 1");
 139         while ($lrow = sqlFetchArray($lres)) {
 140             $white_list[] = $lrow['option_id'];
 141         }
 142     }
 143
 144     $mimetype  = mime_content_type($file);
 145     if (in_array($mimetype, $white_list)) {
 146         return true;
 147     } else {
 148         $splitMimeType = explode('/', $mimetype);
 149         $categoryType = $splitMimeType[0];
 150         if (in_array($categoryType. '/*', $white_list)) {
 151             return true;
 152         }
 153     }
 154
 155     return false;
 156 }
 157
 158 // Sanitize a value to ensure it is a number.
 159 function sanitizeNumber($number)
 160 {
 161     $clean_number = $number +0 ;
 162
 163     if ($clean_number==$number) {
 164         return $clean_number;
 165     } else {
 166         error_log('Custom validation error: Parameter contains non-numeric value (A numeric value expected)');
 167         return $clean_number;
 168     }
 169 }