libraries/grab_globals.lib.php

   1 <?php
   2 /* vim: set expandtab sw=4 ts=4 sts=4: */
   3 /**
   4  * This library grabs the names and values of the variables sent or posted to a
   5  * script in $_GET, $_POST and $_FILES superglobals and sets simple globals
   6  * variables from them. It does the same work for $HTTP_ACCEPT_LANGUAGE and
   7  * $HTTP_AUTHORIZATION.
   8  *
   9  * @package phpMyAdmin
  10  */
  11 if (! defined('PHPMYADMIN')) {
  12     exit;
  13 }
  14
  15 /**
  16  * copy values from one array to another, usually from a superglobal into $GLOBALS
  17  *
  18  * @uses    $GLOBALS['_import_blacklist']
  19  * @uses    preg_replace()
  20  * @uses    array_keys()
  21  * @uses    array_unique()
  22  * @uses    stripslashes()
  23  * @param   array   $array      values from
  24  * @param   array   $target     values to
  25  * @param   boolean $sanitize   prevent importing key names in $_import_blacklist
  26  */
  27 function PMA_recursive_extract($array, &$target, $sanitize = true)
  28 {
  29     if (! is_array($array)) {
  30         return false;
  31     }
  32
  33     if ($sanitize) {
  34         $valid_variables = preg_replace($GLOBALS['_import_blacklist'], '',
  35             array_keys($array));
  36         $valid_variables = array_unique($valid_variables);
  37     } else {
  38         $valid_variables = array_keys($array);
  39     }
  40
  41     foreach ($valid_variables as $key) {
  42
  43         if (strlen($key) === 0) {
  44             continue;
  45         }
  46
  47         if (is_array($array[$key])) {
  48             // there could be a variable coming from a cookie of
  49             // another application, with the same name as this array
  50             unset($target[$key]);
  51
  52             PMA_recursive_extract($array[$key], $target[$key], false);
  53         } else {
  54             $target[$key] = $array[$key];
  55         }
  56     }
  57     return true;
  58 }
  59
  60
  61 /**
  62  * @var array $_import_blacklist variable names that should NEVER be imported
  63  *                              from superglobals
  64  */
  65 $_import_blacklist = array(
  66     '/^cfg$/i',         // PMA configuration
  67     '/^server$/i',      // selected server
  68     '/^db$/i',          // page to display
  69     '/^table$/i',       // page to display
  70     '/^goto$/i',        // page to display
  71     '/^back$/i',        // the page go back
  72     '/^lang$/i',        // selected language
  73     '/^collation_connection$/i', //
  74     '/^set_theme$/i',   //
  75     '/^sql_query$/i',   // the query to be executed
  76     '/^GLOBALS$/i',     // the global scope
  77     '/^str.*$/i',       // PMA localized strings
  78     '/^error_handler.*$/i',       // the error handler
  79     '/^_.*$/i',         // PMA does not use variables starting with _ from extern
  80     '/^.*\s+.*$/i',     // no whitespaces anywhere
  81     '/^[0-9]+.*$/i',    // numeric variable names
  82     //'/^PMA_.*$/i',      // other PMA variables
  83 );
  84
  85 if (! empty($_GET)) {
  86     PMA_recursive_extract($_GET, $GLOBALS);
  87 }
  88
  89 if (! empty($_POST)) {
  90     PMA_recursive_extract($_POST, $GLOBALS);
  91 }
  92
  93 if (! empty($_FILES)) {
  94     $_valid_variables = preg_replace($GLOBALS['_import_blacklist'], '', array_keys($_FILES));
  95     foreach ($_valid_variables as $name) {
  96         if (strlen($name) != 0) {
  97             $$name = $_FILES[$name]['tmp_name'];
  98             ${$name . '_name'} = $_FILES[$name]['name'];
  99         }
 100     }
 101     unset($name, $value);
 102 }
 103
 104 /**
 105  * globalize some environment variables
 106  */
 107 $server_vars = array('HTTP_ACCEPT_LANGUAGE', 'HTTP_AUTHORIZATION');
 108 foreach ($server_vars as $current) {
 109     // it's not important HOW we detect html tags
 110     // it's more important to prevent XSS
 111     // so it's not important if we result in an invalid string,
 112     // it's even better than a XSS capable string
 113     if (PMA_getenv($current) && false === strpos(PMA_getenv($current), '<')) {
 114         $$current = PMA_getenv($current);
 115     // already imported by register_globals?
 116     } elseif (! isset($$current) || false !== strpos($$current, '<')) {
 117         $$current = '';
 118     }
 119 }
 120 unset($server_vars, $current, $_import_blacklist);
 121
 122 ?>