inc/libs/security_functions.php

   1 <?php
   2 /************************************************************************
   3  * MXChange v0.2.1                                    Start: 09/20/2005 *
   4  * ===============                              Last change: 09/20/2005 *
   5  *                                                                      *
   6  * -------------------------------------------------------------------- *
   7  * File              : security_functions.php                           *
   8  * -------------------------------------------------------------------- *
   9  * Short description : Secure all GET, POST and COOKIE data             *
  10  * -------------------------------------------------------------------- *
  11  * Kurzbeschreibung  : Alle GET, POST und COOKIE-Daten sichern          *
  12  * -------------------------------------------------------------------- *
  13  *                                                                      *
  14  * -------------------------------------------------------------------- *
  15  * Copyright (c) 2003 - 2008 by Roland Haeder                           *
  16  * For more information visit: http://www.mxchange.org                  *
  17  *                                                                      *
  18  * This program is free software; you can redistribute it and/or modify *
  19  * it under the terms of the GNU General Public License as published by *
  20  * the Free Software Foundation; either version 2 of the License, or    *
  21  * (at your option) any later version.                                  *
  22  *                                                                      *
  23  * This program is distributed in the hope that it will be useful,      *
  24  * but WITHOUT ANY WARRANTY; without even the implied warranty of       *
  25  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        *
  26  * GNU General Public License for more details.                         *
  27  *                                                                      *
  28  * You should have received a copy of the GNU General Public License    *
  29  * along with this program; if not, write to the Free Software          *
  30  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,               *
  31  * MA  02110-1301  USA                                                  *
  32  ************************************************************************/
  33
  34 // Some security stuff...
  35 if (ereg(basename(__FILE__), $_SERVER['PHP_SELF']))
  36 {
  37         $INC = substr(dirname(__FILE__), 0, strpos(dirname(__FILE__), "/inc") + 4) . "/security.php";
  38         require($INC);
  39 }
  40
  41 /**
  42  * Function to secure input strings
  43  *
  44  * @param       $str    The unsecured string
  45  * @return      $str    A (hopefully) secured string against HTML and other things
  46  */
  47 function secureString ($str) {
  48         $str = trim(strip_tags($str));
  49         $str = htmlentities($str, ENT_QUOTES);
  50         return $str;
  51 }
  52
  53 // Run only once this security check/exchange
  54 if (defined('__SECURITY')) return;
  55
  56 // Fatal messages goes here
  57 global $FATAL;
  58 $FATAL = array();
  59
  60 // Runtime quoting is off now...
  61 set_magic_quotes_runtime(false);
  62
  63 // Unregister all global variables because of vultures and surpress failed attemps
  64 @import_request_variables('');
  65
  66 // Error reporting level
  67 @error_reporting(E_ALL | E_STRICT);
  68
  69 // Check if important arrays are found and define them if missing
  70 if (!isset($_SERVER))
  71 {
  72         global $_SERVER;
  73         $_SERVER = $GLOBALS['_SERVER'];
  74 }
  75 if (!isset($_GET))
  76 {
  77         global $_GET;
  78         $_GET = $GLOBALS['_GET'];
  79 }
  80 if (!isset($_POST))
  81 {
  82         global $_POST;
  83         $_POST = $GLOBALS['_POST'];
  84 }
  85 if (!isset($_SESSION))
  86 {
  87         global $_SESSION;
  88         $_SESSION = $GLOBALS['_COOKIE'];
  89 }
  90
  91 // Include IP-Filter here
  92 //require("/usr/share/php/ipfilter.php");
  93
  94 // Generate arrays which holds the relevante chars to replace
  95 global $SEC_CHARS, $URL_CHARS;
  96 $SEC_CHARS = array(
  97         // The chars we are looking for...
  98         'from' => array("{", "}", "/", ".", "'", "$", "(", ")", "{--", "--}", "%", ";", "[", "]", ":", "--"),
  99         // ... and we will replace to.
 100         'to'   => array(
 101                 "{OPEN_ANCHOR2}",
 102                 "{CLOSE_ANCHOR2}",
 103                 "{SLASH}",
 104                 "{DOT}",
 105                 "{QUOT}",
 106                 "{DOLLAR}",
 107                 "{OPEN_ANCHOR}",
 108                 "{CLOSE_ANCHOR}",
 109                 "{OPEN_TEMPLATE}",
 110                 "{CLOSE_TEMPLATE}",
 111                 "{PER}",
 112                 "{SEMI}",
 113                 "{OPEN_INDEX}",
 114                 "{CLOSE_INDEX}",
 115                 "{DBL_DOT}",
 116                 "{COMMENT}"
 117         ),
 118 );
 119
 120 // Characters allowed in URLs
 121 //
 122 // Note: Do not replace 'to' with 'from' and vise-versa! When you do this all booked URLs will be
 123 //       rejected because of the {SLASH}, {DOT} and all below listed items inside the URL.
 124 $URL_CHARS = array(
 125         // Search for these secured characters
 126         'to'   => array("{SLASH}", "{DOT}", "{PER}", "{DBL_DOT}", "{COMMENT}"),
 127         // Replace with these characters
 128         'from' => array("/", ".", "%", ":", "--")
 129 );
 130
 131 // Overworked security part:
 132 if (is_array($_GET)) {
 133         foreach ($_GET as $seckey=>$secvalue)
 134         {
 135                 if (is_array($secvalue))
 136                 {
 137                         // Throw arrays away...
 138                         unset($_GET[$seckey]);
 139                 }
 140                  else
 141                 {
 142                         // Only variables are allowed (non-array) but we secure them all!
 143                         foreach ($SEC_CHARS['from'] as $key=>$char)
 144                         {
 145                                 // Pass all through
 146                                 $_GET[$seckey] = str_replace($char  , $SEC_CHARS['to'][$key], $_GET[$seckey]);
 147                         }
 148
 149                         // Strip all other out
 150                         $_GET[$seckey] = strip_tags($_GET[$seckey]);
 151                 }
 152         }
 153 }
 154
 155 if (basename($_SERVER['PHP_SELF']) != "install.php")
 156 {
 157         // And POST data
 158         foreach ($_POST as $seckey=>$secvalue)
 159         {
 160                 if (!is_array($secvalue))
 161                 {
 162                         // Only variables are allowed (non-array) to be secured...
 163                         foreach ($SEC_CHARS['from'] as $key=>$char)
 164                         {
 165                                 // Pass all through
 166                                 $_POST[$seckey] = str_replace($char  , $SEC_CHARS['to'][$key], $_POST[$seckey]);
 167                         }
 168
 169                         // Strip all other out
 170                         $_POST[$seckey] = strip_tags($_POST[$seckey]);
 171                 }
 172         }
 173
 174         // ... and finally cookies
 175         foreach ($_SESSION as $seckey=>$secvalue)
 176         {
 177                 if (is_array($secvalue))
 178                 {
 179                         // Throw arrays away...
 180                         unset($_SESSION[$seckey]);
 181                 }
 182                  else
 183                 {
 184                         // Only variables are allowed (non-array) but we secure them all!
 185                         foreach ($SEC_CHARS['from'] as $key=>$char)
 186                         {
 187                                 // Pass all through
 188                                 $_SESSION[$seckey] = str_replace($char  , $SEC_CHARS['to'][$key], $_SESSION[$seckey]);
 189                         }
 190
 191                         // Strip all other out
 192                         $_SESSION[$seckey] = strip_tags($_SESSION[$seckey]);
 193                 }
 194         }
 195 }
 196
 197 // Activate caching or transparent compressing when it is not already done
 198 if (!defined('_OB_CACHING'))
 199 {
 200         if (phpversion() >= '4.0.4pl1' && (strstr(getenv('HTTP_USER_AGENT'),'compatible') || (strstr(getenv('HTTP_USER_AGENT'), "Mozilla"))))
 201         {
 202                 if ((extension_loaded('zlib')) && (function_exists('ob_start')))
 203                 {
 204                         // Start caching
 205                         define('_OB_CACHING', "on");
 206                         ob_start();
 207                 }
 208                  else
 209                 {
 210                         // Extension not loaded or required function is missing
 211                         define('_OB_CACHING', "404");
 212                 }
 213         }
 214          else
 215         {
 216                 // Old PHP version
 217                 define('_OB_CACHING', "old");
 218         }
 219 }
 220
 221 // At last secure the $_SERVER['PHP_SELF'] element
 222 $_SERVER['PHP_SELF'] = secureString($_SERVER['PHP_SELF']);
 223
 224 // Split it up into path and filename
 225 $SELF_DIR  = dirname($_SERVER['PHP_SELF']);
 226 $SELF_FILE = basename($_SERVER['PHP_SELF']);
 227
 228 // Check for a .php inside the $SELF_DIR...
 229 while (ereg(".php", $SELF_DIR))
 230 {
 231         // Correct the dirname
 232         $SELF_DIR = substr($SELF_DIR, 0, (strpos($SELF_DIR, ".php") + 4));
 233         // Rewrite filename...
 234         $SELF_FILE = basename($SELF_DIR);
 235         // ... and dirname
 236         $SELF_DIR = dirname($SELF_DIR);
 237 }
 238
 239 // Put both together again and let's pray it is secured now...
 240 $_SERVER['PHP_SELF'] = $SELF_DIR."/".$SELF_FILE;
 241
 242 // Remove uneccessary variables
 243 unset($SELF_DIR);
 244 unset($SELF_FILE);
 245
 246 // Security system loaded...
 247 define('__SECURITY', "1");
 248
 249 //
 250 ?>