<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');

/**

 * CodeIgniter

 *

 * An open source application development framework for PHP 5.1.6 or newer

 *

 * @package		CodeIgniter

 * @author		ExpressionEngine Dev Team

 * @copyright	Copyright (c) 2008 - 2011, EllisLab, Inc.

 * @license		http://codeigniter.com/user_guide/license.html

 * @link		http://codeigniter.com

 * @since		Version 1.0

 * @filesource

 */



// ------------------------------------------------------------------------



/**

 * Input Class

 *

 * Pre-processes global input data for security

 *

 * @package		CodeIgniter

 * @subpackage	Libraries

 * @category	Input

 * @author		ExpressionEngine Dev Team

 * @link		http://codeigniter.com/user_guide/libraries/input.html

 */

class CI_Input {



	/**

	 * IP address of the current user

	 *

	 * @var string

	 */

	var $ip_address				= FALSE;

	/**

	 * user agent (web browser) being used by the current user

	 *

	 * @var string

	 */

	var $user_agent				= FALSE;

	/**

	 * If FALSE, then $_GET will be set to an empty array

	 *

	 * @var bool

	 */

	var $_allow_get_array		= TRUE;

	/**

	 * If TRUE, then newlines are standardized

	 *

	 * @var bool

	 */

	var $_standardize_newlines	= TRUE;

	/**

	 * Determines whether the XSS filter is always active when GET, POST or COOKIE data is encountered

	 * Set automatically based on config setting

	 *

	 * @var bool

	 */

	var $_enable_xss			= FALSE;

	/**

	 * Enables a CSRF cookie token to be set.

	 * Set automatically based on config setting

	 *

	 * @var bool

	 */

	var $_enable_csrf			= FALSE;

	/**

	 * List of all HTTP request headers

	 *

	 * @var array

	 */

	protected $headers			= array();



	/**

	 * Constructor

	 *

	 * Sets whether to globally enable the XSS processing

	 * and whether to allow the $_GET array

	 *

	 * @return	void

	 */

	public function __construct()

	{

		log_message('debug', "Input Class Initialized");



		$this->_allow_get_array	= (config_item('allow_get_array') === TRUE);

		$this->_enable_xss		= (config_item('global_xss_filtering') === TRUE);

		$this->_enable_csrf		= (config_item('csrf_protection') === TRUE);



		global $SEC;

		$this->security =& $SEC;



		// Do we need the UTF-8 class?

		if (UTF8_ENABLED === TRUE)

		{

			global $UNI;

			$this->uni =& $UNI;

		}



		// Sanitize global arrays

		$this->_sanitize_globals();

	}



	// --------------------------------------------------------------------



	/**

	 * Fetch from array

	 *

	 * This is a helper function to retrieve values from global arrays

	 *

	 * @access	private

	 * @param	array

	 * @param	string

	 * @param	bool

	 * @return	string

	 */

	function _fetch_from_array(&$array, $index = '', $xss_clean = FALSE)

	{

		if ( ! isset($array[$index]))

		{

			return FALSE;

		}



		if ($xss_clean === TRUE)

		{

			return $this->security->xss_clean($array[$index]);

		}



		return $array[$index];

	}



	// --------------------------------------------------------------------



	/**

	* Fetch an item from the GET array

	*

	* @access	public

	* @param	string

	* @param	bool

	* @return	string

	*/

	function get($index = NULL, $xss_clean = FALSE)

	{

		// Check if a field has been provided

		if ($index === NULL AND ! empty($_GET))

		{

			$get = array();



			// loop through the full _GET array

			foreach (array_keys($_GET) as $key)

			{

				$get[$key] = $this->_fetch_from_array($_GET, $key, $xss_clean);

			}

			return $get;

		}



		return $this->_fetch_from_array($_GET, $index, $xss_clean);

	}



	// --------------------------------------------------------------------



	/**

	* Fetch an item from the POST array

	*

	* @access	public

	* @param	string

	* @param	bool

	* @return	string

	*/

	function post($index = NULL, $xss_clean = FALSE)

	{

		// Check if a field has been provided

		if ($index === NULL AND ! empty($_POST))

		{

			$post = array();



			// Loop through the full _POST array and return it

			foreach (array_keys($_POST) as $key)

			{

				$post[$key] = $this->_fetch_from_array($_POST, $key, $xss_clean);

			}

			return $post;

		}



		return $this->_fetch_from_array($_POST, $index, $xss_clean);

	}





	// --------------------------------------------------------------------



	/**

	* Fetch an item from either the GET array or the POST

	*

	* @access	public

	* @param	string	The index key

	* @param	bool	XSS cleaning

	* @return	string

	*/

	function get_post($index = '', $xss_clean = FALSE)

	{

		if ( ! isset($_POST[$index]) )

		{

			return $this->get($index, $xss_clean);

		}

		else

		{

			return $this->post($index, $xss_clean);

		}

	}



	// --------------------------------------------------------------------



	/**

	* Fetch an item from the COOKIE array

	*

	* @access	public

	* @param	string

	* @param	bool

	* @return	string

	*/

	function cookie($index = '', $xss_clean = FALSE)

	{

		return $this->_fetch_from_array($_COOKIE, $index, $xss_clean);

	}



	// ------------------------------------------------------------------------



	/**

	* Set cookie

	*

	* Accepts six parameter, or you can submit an associative

	* array in the first parameter containing all the values.

	*

	* @access	public

	* @param	mixed

	* @param	string	the value of the cookie

	* @param	string	the number of seconds until expiration

	* @param	string	the cookie domain.  Usually:  .yourdomain.com

	* @param	string	the cookie path

	* @param	string	the cookie prefix

	* @param	bool	true makes the cookie secure

	* @return	void

	*/

	function set_cookie($name = '', $value = '', $expire = '', $domain = '', $path = '/', $prefix = '', $secure = FALSE)

	{

		if (is_array($name))

		{

			// always leave 'name' in last place, as the loop will break otherwise, due to $$item

			foreach (array('value', 'expire', 'domain', 'path', 'prefix', 'secure', 'name') as $item)

			{

				if (isset($name[$item]))

				{

					$$item = $name[$item];

				}

			}

		}



		if ($prefix == '' AND config_item('cookie_prefix') != '')

		{

			$prefix = config_item('cookie_prefix');

		}

		if ($domain == '' AND config_item('cookie_domain') != '')

		{

			$domain = config_item('cookie_domain');

		}

		if ($path == '/' AND config_item('cookie_path') != '/')

		{

			$path = config_item('cookie_path');

		}

		if ($secure == FALSE AND config_item('cookie_secure') != FALSE)

		{

			$secure = config_item('cookie_secure');

		}



		if ( ! is_numeric($expire))

		{

			$expire = time() - 86500;

		}

		else

		{

			$expire = ($expire > 0) ? time() + $expire : 0;

		}



		setcookie($prefix.$name, $value, $expire, $path, $domain, $secure);

	}



	// --------------------------------------------------------------------



	/**

	* Fetch an item from the SERVER array

	*

	* @access	public

	* @param	string

	* @param	bool

	* @return	string

	*/

	function server($index = '', $xss_clean = FALSE)

	{

		return $this->_fetch_from_array($_SERVER, $index, $xss_clean);

	}



	// --------------------------------------------------------------------



	/**

	* Fetch the IP Address

	*

	* @return	string

	*/

	public function ip_address()

	{

		if ($this->ip_address !== FALSE)

		{

			return $this->ip_address;

		}



		$proxy_ips = config_item('proxy_ips');

		if ( ! empty($proxy_ips))

		{

			$proxy_ips = explode(',', str_replace(' ', '', $proxy_ips));

			foreach (array('HTTP_X_FORWARDED_FOR', 'HTTP_CLIENT_IP', 'HTTP_X_CLIENT_IP', 'HTTP_X_CLUSTER_CLIENT_IP') as $header)

			{

				if (($spoof = $this->server($header)) !== FALSE)

				{

					// Some proxies typically list the whole chain of IP

					// addresses through which the client has reached us.

					// e.g. client_ip, proxy_ip1, proxy_ip2, etc.

					if (strpos($spoof, ',') !== FALSE)

					{

						$spoof = explode(',', $spoof, 2);

						$spoof = $spoof[0];

					}



					if ( ! $this->valid_ip($spoof))

					{

						$spoof = FALSE;

					}

					else

					{

						break;

					}

				}

			}



			$this->ip_address = ($spoof !== FALSE && in_array($_SERVER['REMOTE_ADDR'], $proxy_ips, TRUE))

				? $spoof : $_SERVER['REMOTE_ADDR'];

		}

		else

		{

			$this->ip_address = $_SERVER['REMOTE_ADDR'];

		}



		if ( ! $this->valid_ip($this->ip_address))

		{

			$this->ip_address = '0.0.0.0';

		}



		return $this->ip_address;

	}



	// --------------------------------------------------------------------



	/**

	* Validate IP Address

	*

	* @access	public

	* @param	string

	* @param	string	ipv4 or ipv6

	* @return	bool

	*/

	public function valid_ip($ip, $which = '')

	{

		$which = strtolower($which);



		// First check if filter_var is available

		if (is_callable('filter_var'))

		{

			switch ($which) {

				case 'ipv4':

					$flag = FILTER_FLAG_IPV4;

					break;

				case 'ipv6':

					$flag = FILTER_FLAG_IPV6;

					break;

				default:

					$flag = '';

					break;

			}



			return (bool) filter_var($ip, FILTER_VALIDATE_IP, $flag);

		}



		if ($which !== 'ipv6' && $which !== 'ipv4')

		{

			if (strpos($ip, ':') !== FALSE)

			{

				$which = 'ipv6';

			}

			elseif (strpos($ip, '.') !== FALSE)

			{

				$which = 'ipv4';

			}

			else

			{

				return FALSE;

			}

		}



		$func = '_valid_'.$which;

		return $this->$func($ip);

	}



	// --------------------------------------------------------------------



	/**

	* Validate IPv4 Address

	*

	* Updated version suggested by Geert De Deckere

	*

	* @access	protected

	* @param	string

	* @return	bool

	*/

	protected function _valid_ipv4($ip)

	{

		$ip_segments = explode('.', $ip);



		// Always 4 segments needed

		if (count($ip_segments) !== 4)

		{

			return FALSE;

		}

		// IP can not start with 0

		if ($ip_segments[0][0] == '0')

		{

			return FALSE;

		}



		// Check each segment

		foreach ($ip_segments as $segment)

		{

			// IP segments must be digits and can not be

			// longer than 3 digits or greater then 255

			if ($segment == '' OR preg_match("/[^0-9]/", $segment) OR $segment > 255 OR strlen($segment) > 3)

			{

				return FALSE;

			}

		}



		return TRUE;

	}



	// --------------------------------------------------------------------



	/**

	* Validate IPv6 Address

	*

	* @access	protected

	* @param	string

	* @return	bool

	*/

	protected function _valid_ipv6($str)

	{

		// 8 groups, separated by :

		// 0-ffff per group

		// one set of consecutive 0 groups can be collapsed to ::



		$groups = 8;

		$collapsed = FALSE;



		$chunks = array_filter(

			preg_split('/(:{1,2})/', $str, NULL, PREG_SPLIT_DELIM_CAPTURE)

		);



		// Rule out easy nonsense

		if (current($chunks) == ':' OR end($chunks) == ':')

		{

			return FALSE;

		}



		// PHP supports IPv4-mapped IPv6 addresses, so we'll expect those as well

		if (strpos(end($chunks), '.') !== FALSE)

		{

			$ipv4 = array_pop($chunks);



			if ( ! $this->_valid_ipv4($ipv4))

			{

				return FALSE;

			}



			$groups--;

		}



		while ($seg = array_pop($chunks))

		{

			if ($seg[0] == ':')

			{

				if (--$groups == 0)

				{

					return FALSE;	// too many groups

				}



				if (strlen($seg) > 2)

				{

					return FALSE;	// long separator

				}



				if ($seg == '::')

				{

					if ($collapsed)

					{

						return FALSE;	// multiple collapsed

					}



					$collapsed = TRUE;

				}

			}

			elseif (preg_match("/[^0-9a-f]/i", $seg) OR strlen($seg) > 4)

			{

				return FALSE; // invalid segment

			}

		}



		return $collapsed OR $groups == 1;

	}



	// --------------------------------------------------------------------



	/**

	* User Agent

	*

	* @access	public

	* @return	string

	*/

	function user_agent()

	{

		if ($this->user_agent !== FALSE)

		{

			return $this->user_agent;

		}



		$this->user_agent = ( ! isset($_SERVER['HTTP_USER_AGENT'])) ? FALSE : $_SERVER['HTTP_USER_AGENT'];



		return $this->user_agent;

	}



	// --------------------------------------------------------------------



	/**

	* Sanitize Globals

	*

	* This function does the following:

	*

	* Unsets $_GET data (if query strings are not enabled)

	*

	* Unsets all globals if register_globals is enabled

	*

	* Standardizes newline characters to \n

	*

	* @access	private

	* @return	void

	*/

	function _sanitize_globals()

	{

		// It would be "wrong" to unset any of these GLOBALS.

		$protected = array('_SERVER', '_GET', '_POST', '_FILES', '_REQUEST',

							'_SESSION', '_ENV', 'GLOBALS', 'HTTP_RAW_POST_DATA',

							'system_folder', 'application_folder', 'BM', 'EXT',

							'CFG', 'URI', 'RTR', 'OUT', 'IN');



		// Unset globals for securiy.

		// This is effectively the same as register_globals = off

		foreach (array($_GET, $_POST, $_COOKIE) as $global)

		{

			if ( ! is_array($global))

			{

				if ( ! in_array($global, $protected))

				{

					global $$global;

					$$global = NULL;

				}

			}

			else

			{

				foreach ($global as $key => $val)

				{

					if ( ! in_array($key, $protected))

					{

						global $$key;

						$$key = NULL;

					}

				}

			}

		}



		// Is $_GET data allowed? If not we'll set the $_GET to an empty array

		if ($this->_allow_get_array == FALSE)

		{

			$_GET = array();

		}

		else

		{

			if (is_array($_GET) AND count($_GET) > 0)

			{

				foreach ($_GET as $key => $val)

				{

					$_GET[$this->_clean_input_keys($key)] = $this->_clean_input_data($val);

				}

			}

		}



		// Clean $_POST Data

		if (is_array($_POST) AND count($_POST) > 0)

		{

			foreach ($_POST as $key => $val)

			{

				$_POST[$this->_clean_input_keys($key)] = $this->_clean_input_data($val);

			}

		}



		// Clean $_COOKIE Data

		if (is_array($_COOKIE) AND count($_COOKIE) > 0)

		{

			// Also get rid of specially treated cookies that might be set by a server

			// or silly application, that are of no use to a CI application anyway

			// but that when present will trip our 'Disallowed Key Characters' alarm

			// http://www.ietf.org/rfc/rfc2109.txt

			// note that the key names below are single quoted strings, and are not PHP variables

			unset($_COOKIE['$Version']);

			unset($_COOKIE['$Path']);

			unset($_COOKIE['$Domain']);



			foreach ($_COOKIE as $key => $val)

			{

				$_COOKIE[$this->_clean_input_keys($key)] = $this->_clean_input_data($val);

			}

		}



		// Sanitize PHP_SELF

		$_SERVER['PHP_SELF'] = strip_tags($_SERVER['PHP_SELF']);





		// CSRF Protection check on HTTP requests

		if ($this->_enable_csrf == TRUE && ! $this->is_cli_request())

		{

			$this->security->csrf_verify();

		}



		log_message('debug', "Global POST and COOKIE data sanitized");

	}



	// --------------------------------------------------------------------



	/**

	* Clean Input Data

	*

	* This is a helper function. It escapes data and

	* standardizes newline characters to \n

	*

	* @access	private

	* @param	string

	* @return	string

	*/

	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;

		}



		/* We strip slashes if magic quotes is on to keep things consistent



		   NOTE: In PHP 5.4 get_magic_quotes_gpc() will always return 0 and

			 it will probably not exist in future versions at all.

		*/

		if ( ! is_php('5.4') && get_magic_quotes_gpc())

		{

			$str = stripslashes($str);

		}



		// Clean UTF-8 if supported

		if (UTF8_ENABLED === TRUE)

		{

			$str = $this->uni->clean_string($str);

		}



		// Remove control characters

		$str = remove_invisible_characters($str);



		// Should we filter the input data?

		if ($this->_enable_xss === TRUE)

		{

			$str = $this->security->xss_clean($str);

		}



		// Standardize newlines if needed

		if ($this->_standardize_newlines == TRUE)

		{

			if (strpos($str, "\r") !== FALSE)

			{

				$str = str_replace(array("\r\n", "\r", "\r\n\n"), PHP_EOL, $str);

			}

		}



		return $str;

	}



	// --------------------------------------------------------------------



	/**

	* Clean Keys

	*

	* 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.

	*

	* @access	private

	* @param	string

	* @return	string

	*/

	function _clean_input_keys($str)

	{

		if ( ! preg_match("/^[a-z0-9:_\/-]+$/i", $str))

		{

			exit('Disallowed Key Characters.');

		}



		// Clean UTF-8 if supported

		if (UTF8_ENABLED === TRUE)

		{

			$str = $this->uni->clean_string($str);

		}



		return $str;

	}



	// --------------------------------------------------------------------



	/**

	 * Request Headers

	 *

	 * In Apache, you can simply call apache_request_headers(), however for

	 * people running other webservers the function is undefined.

	 *

	 * @param	bool XSS cleaning

	 *

	 * @return array

	 */

	public function request_headers($xss_clean = FALSE)

	{

		// Look at Apache go!

		if (function_exists('apache_request_headers'))

		{

			$headers = apache_request_headers();

		}

		else

		{

			$headers['Content-Type'] = (isset($_SERVER['CONTENT_TYPE'])) ? $_SERVER['CONTENT_TYPE'] : @getenv('CONTENT_TYPE');



			foreach ($_SERVER as $key => $val)

			{

				if (strncmp($key, 'HTTP_', 5) === 0)

				{

					$headers[substr($key, 5)] = $this->_fetch_from_array($_SERVER, $key, $xss_clean);

				}

			}

		}



		// take SOME_HEADER and turn it into Some-Header

		foreach ($headers as $key => $val)

		{

			$key = str_replace('_', ' ', strtolower($key));

			$key = str_replace(' ', '-', ucwords($key));



			$this->headers[$key] = $val;

		}



		return $this->headers;

	}



	// --------------------------------------------------------------------



	/**

	 * Get Request Header

	 *

	 * Returns the value of a single member of the headers class member

	 *

	 * @param 	string		array key for $this->headers

	 * @param	boolean		XSS Clean or not

	 * @return 	mixed		FALSE on failure, string on success

	 */

	public function get_request_header($index, $xss_clean = FALSE)

	{

		if (empty($this->headers))

		{

			$this->request_headers();

		}



		if ( ! isset($this->headers[$index]))

		{

			return FALSE;

		}



		if ($xss_clean === TRUE)

		{

			return $this->security->xss_clean($this->headers[$index]);

		}



		return $this->headers[$index];

	}



	// --------------------------------------------------------------------



	/**

	 * Is ajax Request?

	 *

	 * Test to see if a request contains the HTTP_X_REQUESTED_WITH header

	 *

	 * @return 	boolean

	 */

	public function is_ajax_request()

	{

		return ($this->server('HTTP_X_REQUESTED_WITH') === 'XMLHttpRequest');

	}



	// --------------------------------------------------------------------



	/**

	 * Is cli Request?

	 *

	 * Test to see if a request was made from the command line

	 *

	 * @return 	bool

	 */

	public function is_cli_request()

	{

		return (php_sapi_name() === 'cli' OR defined('STDIN'));

	}



}



/* End of file Input.php */

/* Location: ./system/core/Input.php */