freenetis-github/system/libraries/Input.php @ a82b9445
8baed187 | Michal Kliment | <?php defined('SYSPATH') or die('No direct script access.');
|
|
/**
|
|||
* Input library.
|
|||
*
|
|||
* $Id: Input.php 1911 2008-02-04 16:13:16Z PugFish $
|
|||
*
|
|||
* @package Core
|
|||
* @author Kohana Team
|
|||
* @copyright (c) 2007-2008 Kohana Team
|
|||
* @license http://kohanaphp.com/license.html
|
|||
*/
|
|||
class Input {
|
|||
// Singleton instance
|
|||
protected static $instance;
|
|||
protected $use_xss_clean = FALSE;
|
|||
public $ip_address = FALSE;
|
|||
public $user_agent = FALSE;
|
|||
/**
|
|||
* Retrieve a singleton instance of Input. This will always be the first
|
|||
* created instance of this class.
|
|||
*
|
|||
* @return object
|
|||
*/
|
|||
public static function instance()
|
|||
{
|
|||
// Create an instance if none exists
|
|||
empty(self::$instance) and new Input;
|
|||
return self::$instance;
|
|||
}
|
|||
/**
|
|||
* Sets whether to globally enable the XSS processing.
|
|||
*/
|
|||
public function __construct()
|
|||
{
|
|||
// Use XSS clean?
|
|||
$this->use_xss_clean = (bool) Config::get('core.global_xss_filtering');
|
|||
if (self::$instance === NULL)
|
|||
{
|
|||
$this->user_agent = Kohana::$user_agent;
|
|||
if (ini_get('register_globals'))
|
|||
{
|
|||
// Prevent GLOBALS override attacks
|
|||
isset($_REQUEST['GLOBALS']) and exit('Global variable overload attack.');
|
|||
// Destroy the REQUEST global
|
|||
$_REQUEST = array();
|
|||
// These globals are standard and should not be removed
|
|||
$preserve = array('GLOBALS', '_REQUEST', '_GET', '_POST', '_FILES', '_COOKIE', '_SERVER', '_ENV', '_SESSION');
|
|||
// This loop has the same effect as disabling register_globals
|
|||
foreach ($GLOBALS as $key => $val)
|
|||
{
|
|||
if ( ! in_array($key, $preserve))
|
|||
{
|
|||
// NULL-ify the global variable
|
|||
global $$key;
|
|||
$$key = NULL;
|
|||
// Unset the global variable
|
|||
unset($GLOBALS[$key]);
|
|||
unset($$key);
|
|||
}
|
|||
}
|
|||
// Warn the developer about register globals
|
|||
Log::add('debug', 'Register globals is enabled. To save resources, disable register_globals in php.ini');
|
|||
}
|
|||
if (is_array($_GET) AND count($_GET) > 0)
|
|||
{
|
|||
foreach ($_GET as $key => $val)
|
|||
{
|
|||
// Sanitize $_GET
|
|||
$_GET[$this->clean_input_keys($key)] = $this->clean_input_data($val);
|
|||
}
|
|||
}
|
|||
else
|
|||
{
|
|||
$_GET = array();
|
|||
}
|
|||
if (is_array($_POST) AND count($_POST) > 0)
|
|||
{
|
|||
foreach ($_POST as $key => $val)
|
|||
{
|
|||
// Sanitize $_POST
|
|||
$_POST[$this->clean_input_keys($key)] = $this->clean_input_data($val);
|
|||
}
|
|||
}
|
|||
else
|
|||
{
|
|||
$_POST = array();
|
|||
}
|
|||
if (is_array($_COOKIE) AND count($_COOKIE) > 0)
|
|||
{
|
|||
foreach ($_COOKIE as $key => $val)
|
|||
{
|
|||
// Sanitize $_COOKIE
|
|||
$_COOKIE[$this->clean_input_keys($key)] = $this->clean_input_data($val);
|
|||
}
|
|||
}
|
|||
else
|
|||
{
|
|||
$_COOKIE = array();
|
|||
}
|
|||
// Create a singleton
|
|||
self::$instance = $this;
|
|||
Log::add('debug', 'Global GET, POST and COOKIE data sanitized');
|
|||
}
|
|||
Log::add('debug', 'Input Library initialized');
|
|||
}
|
|||
/**
|
|||
* Fetch an item from a global array.
|
|||
*
|
|||
* @param string array to access (get, post, cookie or server)
|
|||
* @param array arguments (array key, xss_clean)
|
|||
* @return mixed
|
|||
*/
|
|||
public function __call($global, $args = array())
|
|||
{
|
|||
// Array to be searched, assigned by reference
|
|||
$array = array();
|
|||
switch (strtolower($global))
|
|||
{
|
|||
case 'get': $array =& $_GET; break;
|
|||
case 'post': $array =& $_POST; break;
|
|||
case 'cookie': $array =& $_COOKIE; break;
|
|||
case 'server': $array =& $_SERVER; break;
|
|||
default:
|
|||
throw new Kohana_Exception('core.invalid_method', $global, get_class($this));
|
|||
}
|
|||
if (count($args) === 0)
|
|||
return $array;
|
|||
// If the last argument is a boolean, it's the XSS clean flag
|
|||
$xss_clean = (is_bool(end($args))) ? array_pop($args) : FALSE;
|
|||
// Reset the array pointer
|
|||
reset($args);
|
|||
// Multiple inputs require us to return an array
|
|||
$return_array = (count($args) > 1);
|
|||
// Compose the data to return
|
|||
$data = array();
|
|||
while ($key = array_shift($args))
|
|||
{
|
|||
if (isset($array[$key]))
|
|||
{
|
|||
// XSS clean if the data has not already been cleaned
|
|||
$data[$key] = ($this->use_xss_clean == FALSE AND $xss_clean == TRUE) ? $this->xss_clean($array[$key]) : $array[$key];
|
|||
}
|
|||
else
|
|||
{
|
|||
$data[$key] = NULL;
|
|||
}
|
|||
}
|
|||
// Return the global value
|
|||
return ($return_array) ? $data : current($data);
|
|||
}
|
|||
/**
|
|||
* This is a helper function. It escapes data and standardizes newline characters to '\n'.
|
|||
*
|
|||
* @param unknown_type string to clean
|
|||
* @return string
|
|||
*/
|
|||
protected function clean_input_data($str)
|
|||
{
|
|||
if (is_array($str))
|
|||
{
|
|||
$new_array = array();
|
|||
foreach ($str as $key => $val)
|
|||
{
|
|||
$new_array[$this->clean_input_keys($key)] = $this->clean_input_data($val);
|
|||
}
|
|||
return $new_array;
|
|||
}
|
|||
if (get_magic_quotes_gpc())
|
|||
{
|
|||
$str = stripslashes($str);
|
|||
}
|
|||
if ($this->use_xss_clean === TRUE)
|
|||
{
|
|||
$str = $this->xss_clean($str);
|
|||
}
|
|||
// Standardize newlines
|
|||
return str_replace(array("\r\n", "\r"), "\n", $str);
|
|||
}
|
|||
/**
|
|||
* This is a helper function. To prevent malicious users
|
|||
* from trying to exploit keys we make sure that keys are
|
|||
* only named with alpha-numeric text and a few other items.
|
|||
*
|
|||
* @param string string to clean
|
|||
* @return string
|
|||
*/
|
|||
protected function clean_input_keys($str)
|
|||
{
|
|||
$chars = (PCRE_UNICODE_PROPERTIES) ? '\pL' : 'a-zA-Z';
|
|||
if ( ! preg_match('#^['.$chars.'0-9:_/-]+$#uD', $str))
|
|||
{
|
|||
exit('Disallowed key characters in global data.');
|
|||
}
|
|||
return $str;
|
|||
}
|
|||
/**
|
|||
* Fetch the IP Address.
|
|||
*
|
|||
* @return string
|
|||
*/
|
|||
public function ip_address()
|
|||
{
|
|||
if ($this->ip_address !== FALSE)
|
|||
return $this->ip_address;
|
|||
if ($this->server('REMOTE_ADDR') AND $this->server('HTTP_CLIENT_IP'))
|
|||
{
|
|||
$this->ip_address = $_SERVER['HTTP_CLIENT_IP'];
|
|||
}
|
|||
elseif ($this->server('REMOTE_ADDR'))
|
|||
{
|
|||
$this->ip_address = $_SERVER['REMOTE_ADDR'];
|
|||
}
|
|||
elseif ($this->server('HTTP_CLIENT_IP'))
|
|||
{
|
|||
$this->ip_address = $_SERVER['HTTP_CLIENT_IP'];
|
|||
}
|
|||
elseif ($this->server('HTTP_X_FORWARDED_FOR'))
|
|||
{
|
|||
$this->ip_address = $_SERVER['HTTP_X_FORWARDED_FOR'];
|
|||
}
|
|||
if ($this->ip_address === FALSE)
|
|||
{
|
|||
$this->ip_address = '0.0.0.0';
|
|||
return $this->ip_address;
|
|||
}
|
|||
if (strstr($this->ip_address, ','))
|
|||
{
|
|||
$x = explode(',', $this->ip_address);
|
|||
$this->ip_address = end($x);
|
|||
}
|
|||
if ( ! $this->valid_ip($this->ip_address))
|
|||
{
|
|||
$this->ip_address = '0.0.0.0';
|
|||
}
|
|||
return $this->ip_address;
|
|||
}
|
|||
/**
|
|||
* Validates an IPv4 address based on RFC specifications.
|
|||
*
|
|||
* @param string IP to validate
|
|||
* @return boolean
|
|||
*/
|
|||
public function valid_ip($ip)
|
|||
{
|
|||
return valid::ip($ip);
|
|||
}
|
|||
/**
|
|||
* Get the user agent of the current request.
|
|||
*
|
|||
* @return string
|
|||
*/
|
|||
public function user_agent()
|
|||
{
|
|||
return $this->user_agent;
|
|||
}
|
|||
/**
|
|||
* Clean cross site scripting exploits from string.
|
|||
* HTMLPurifier may be used if installed, otherwise defaults to built in method.
|
|||
* Note - This function should only be used to deal with data upon submission.
|
|||
* It's not something that should be used for general runtime processing
|
|||
* since it requires a fair amount of processing overhead.
|
|||
*
|
|||
* @param string data to clean
|
|||
* @param string xss_clean method to use ('htmlpurifier' or defaults to built in method)
|
|||
* @return string
|
|||
*/
|
|||
public function xss_clean($data, $tool = NULL)
|
|||
{
|
|||
if (is_array($data))
|
|||
{
|
|||
foreach ($data as $key => $val)
|
|||
{
|
|||
$data[$key] = $this->xss_clean($val, $tool);
|
|||
}
|
|||
return $data;
|
|||
}
|
|||
// It is a string
|
|||
$string = $data;
|
|||
// Do not clean empty strings
|
|||
if (trim($string) == '')
|
|||
return $string;
|
|||
if ( ! is_string($tool))
|
|||
{
|
|||
// Fetch the configured tool
|
|||
if (is_bool($tool = Config::get('core.global_xss_filtering')))
|
|||
{
|
|||
// Make sure that the default tool is used
|
|||
$tool = 'default';
|
|||
}
|
|||
}
|
|||
switch ($tool)
|
|||
{
|
|||
case 'htmlpurifier':
|
|||
/**
|
|||
* @todo License should go here, http://htmlpurifier.org/
|
|||
*/
|
|||
require_once Kohana::find_file('vendor', 'htmlpurifier/HTMLPurifier.auto');
|
|||
require_once 'HTMLPurifier.func.php';
|
|||
// Set configuration
|
|||
$config = HTMLPurifier_Config::createDefault();
|
|||
$config->set('HTML', 'TidyLevel', 'none'); // Only XSS cleaning now
|
|||
// Run HTMLPurifier
|
|||
$string = HTMLPurifier($string, $config);
|
|||
break;
|
|||
default:
|
|||
// http://svn.bitflux.ch/repos/public/popoon/trunk/classes/externalinput.php
|
|||
// +----------------------------------------------------------------------+
|
|||
// | Copyright (c) 2001-2006 Bitflux GmbH |
|
|||
// +----------------------------------------------------------------------+
|
|||
// | Licensed under the Apache License, Version 2.0 (the "License"); |
|
|||
// | you may not use this file except in compliance with the License. |
|
|||
// | You may obtain a copy of the License at |
|
|||
// | http://www.apache.org/licenses/LICENSE-2.0 |
|
|||
// | Unless required by applicable law or agreed to in writing, software |
|
|||
// | distributed under the License is distributed on an "AS IS" BASIS, |
|
|||
// | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or |
|
|||
// | implied. See the License for the specific language governing |
|
|||
// | permissions and limitations under the License. |
|
|||
// +----------------------------------------------------------------------+
|
|||
// | Author: Christian Stocker <chregu@bitflux.ch> |
|
|||
// +----------------------------------------------------------------------+
|
|||
//
|
|||
// Kohana Modifications:
|
|||
// * Changed double quotes to single quotes, changed indenting and spacing
|
|||
// * Removed magic_quotes stuff
|
|||
// * Increased regex readability:
|
|||
// * Used delimeters that aren't found in the pattern
|
|||
// * Removed all unneeded escapes
|
|||
// * Deleted U modifiers and swapped greediness where needed
|
|||
// * Increased regex speed:
|
|||
// * Made capturing parentheses non-capturing where possible
|
|||
// * Removed parentheses where possible
|
|||
// * Split up alternation alternatives
|
|||
//
|
|||
$string = str_replace(array('&','<','>'), array('&amp;','&lt;','&gt;'), $string);
|
|||
// fix &entitiy\n;
|
|||
$string = preg_replace('/(&#*\w+)[\x00-\x20]+;/u', '$1;', $string);
|
|||
$string = preg_replace('/(&#x*[0-9A-F]+);*/iu', '$1;', $string);
|
|||
$string = html_entity_decode($string, ENT_COMPAT, 'UTF-8');
|
|||
// remove any attribute starting with "on" or xmlns
|
|||
$string = preg_replace('#(<[^>]+?[\x00-\x20"\'])(?:on|xmlns)[^>]*>#iu', '$1>', $string);
|
|||
// remove javascript: and vbscript: protocol
|
|||
$string = preg_replace('#([a-z]*)[\x00-\x20]*=[\x00-\x20]*([`\'"]*)[\x00-\x20]*j[\x00-\x20]*a[\x00-\x20]*v[\x00-\x20]*a[\x00-\x20]*s[\x00-\x20]*c[\x00-\x20]*r[\x00-\x20]*i[\x00-\x20]*p[\x00-\x20]*t[\x00-\x20]*:#iu', '$1=$2nojavascript...', $string);
|
|||
$string = preg_replace('#([a-z]*)[\x00-\x20]*=([\'"]*)[\x00-\x20]*v[\x00-\x20]*b[\x00-\x20]*s[\x00-\x20]*c[\x00-\x20]*r[\x00-\x20]*i[\x00-\x20]*p[\x00-\x20]*t[\x00-\x20]*:#iu', '$1=$2novbscript...', $string);
|
|||
$string = preg_replace('#([a-z]*)[\x00-\x20]*=([\'"]*)[\x00-\x20]*-moz-binding[\x00-\x20]*:#u', '$1=$2nomozbinding...', $string);
|
|||
//<span style="width: expression(alert('Ping!'));"></span>
|
|||
// only works in ie...
|
|||
$string = preg_replace('#(<[^>]+?)style[\x00-\x20]*=[\x00-\x20]*[`\'"]*.*?expression[\x00-\x20]*\([^>]*>#i', '$1>', $string);
|
|||
$string = preg_replace('#(<[^>]+?)style[\x00-\x20]*=[\x00-\x20]*[`\'"]*.*?behaviour[\x00-\x20]*\([^>]*>#i', '$1>', $string);
|
|||
$string = preg_replace('#(<[^>]+?)style[\x00-\x20]*=[\x00-\x20]*[`\'"]*.*?s[\x00-\x20]*c[\x00-\x20]*r[\x00-\x20]*i[\x00-\x20]*p[\x00-\x20]*t[\x00-\x20]*:*[^>]*>#iu', '$1>', $string);
|
|||
//remove namespaced elements (we do not need them...)
|
|||
$string = preg_replace('#</*\w+:\w[^>]*>#i', '',$string);
|
|||
//remove really unwanted tags
|
|||
do {
|
|||
$oldstring = $string;
|
|||
$string = preg_replace('#</*(?:applet|b(?:ase|gsound|link)|embed|frame(?:set)?|i(?:frame|layer)|l(?:ayer|ink)|meta|object|s(?:cript|tyle)|title|xml)[^>]*>#i', '', $string);
|
|||
} while ($oldstring != $string);
|
|||
break;
|
|||
}
|
|||
return $string;
|
|||
}
|
|||
} // End Input Class
|