add some properties

[phpbb.git] / phpBB / includes / core / system_info.php

<?php
/**
*
* @package core
* @version $Id$
* @copyright (c) 2008 phpBB Group
* @license http://opensource.org/licenses/gpl-license.php GNU Public License
*
*/

/**
* @ignore
*/
if (!defined('IN_PHPBB'))
{
        exit();
}

/**
* Get system/server information variables.
*
* @package core
*/
class phpbb_system_info extends phpbb_plugin_support implements ArrayAccess
{
        /**
        * @var array required phpBB objects
        */
        public $phpbb_required = array('config', 'url');

        /**
        * @var array Optional phpBB objects
        */
        public $phpbb_optional = array();

        /**
        * @var array Array for storing/accessing information
        */
        private $data = array();

        /**#@+
        * Part of the ArrayAccess implementation.
        * @access public
        */
        public function offsetSet($offset, $value)
        {
                $this->data[$offset] = $value;
        }

        public function offsetExists($offset)
        {
                return isset($this->data[$offset]);
        }

        public function offsetUnset($offset)
        {
                unset($this->data[$offset]);
        }
        /**#@-*/

        /**
        * Get system information - Part of the ArrayAccess implementation.
        *
        * System information ought to be received from {@link $data phpbb::$user->system[key]}.
        * The key used is mapped to a method with get_ as prefix.
        * For example getting phpbb::$user->system['host'] results in calling the method get_host().
        *
        * @param string $offset The key to get.
        * @return mixed The result
        * @access public
        */
        public function offsetGet($offset)
        {
                if (isset($this->data[$offset]))
                {
                        return $this->data[$offset];
                }

                $identifier = 'get_' . strtolower($offset);

                // Not static, because we are not able to use late static bindings
                $this->data[$offset] = $this->$identifier();
                return $this->data[$offset];
        }

        /**
        * Get valid hostname/port. HTTP_HOST is used, SERVER_NAME if HTTP_HOST not present.
        *
        * @return string        Host (lowercase, not specialchared)
        * @access protected
        */
        protected function get_host()
        {
                // Get hostname
                $host = (!empty($_SERVER['HTTP_HOST'])) ? $_SERVER['HTTP_HOST'] : ((!empty($_SERVER['SERVER_NAME'])) ? $_SERVER['SERVER_NAME'] : getenv('SERVER_NAME'));

                // Should be a string and lowered
                $host = (string) strtolower($host);

                // If host is equal the cookie domain or the server name (if config is set), then we assume it is valid
                if ((isset(phpbb::$config['cookie_domain']) && $host === phpbb::$config['cookie_domain']) || (isset(phpbb::$config['server_name']) && $host === phpbb::$config['server_name']))
                {
                        return $host;
                }

                // Is the host actually a IP? If so, we use the IP... (IPv4)
                if (long2ip(ip2long($host)) === $host)
                {
                        return $host;
                }

                // Now return the hostname (this also removes any port definition). The http:// is prepended to construct a valid URL, hosts never have a scheme assigned
                $host = @parse_url('http://' . $host, PHP_URL_HOST);

                // Remove any portions not removed by parse_url (#)
                $host = str_replace('#', '', $host);

                // If, by any means, the host is now empty, we will use a "best approach" way to guess one
                if (empty($host))
                {
                        if (!empty(phpbb::$config['server_name']))
                        {
                                $host = phpbb::$config['server_name'];
                        }
                        else if (!empty(phpbb::$config['cookie_domain']))
                        {
                                $host = (strpos(phpbb::$config['cookie_domain'], '.') === 0) ? substr(phpbb::$config['cookie_domain'], 1) : phpbb::$config['cookie_domain'];
                        }
                        else
                        {
                                // Set to OS hostname or localhost
                                $host = (function_exists('php_uname')) ? strtolower(php_uname('n')) : 'localhost';
                        }
                }

                // It may be still no valid host, but for sure only a hostname (we may further expand on the cookie domain... if set)
                return $host;
        }

        /**
        * Extract current session page, relative from current root path (PHPBB_ROOT_PATH)
        *
        * The array returned consist of the following key/value pairs:
        * page_name:            The current basename'd page name, for example: index.php (urlencoded, htmlspecialchared)
        * page_dir:                     The current directory within the phpBB root, for example: adm
        * query_string:         The current query string, for example: i=10&b=2 (the parameter 'sid' is never included)
        * script_path:          The script path from the webroot to the current directory, for example: /phpBB3/adm/
        *                                       The script path is always prefixed with / and ends in /. Specialchared, whitespace replaced with %20.
        * root_script_path:     The script path from the webroot to the phpBB root, for example: /phpBB3/
        *                                       The root script path is always prefixed with / and ends in /. Specialchared, whitespace replaced with %20.
        * page:                         Current page from phpBB root, for example: adm/index.php?i=10&b=2
        * forum:                        Current forum id (determined by {@link request_var() request_var('f', 0)})
        *
        * @return array         Array containing page information.
        * @plugin-support       return
        * @access protected
        */
        protected function get_page()
        {
                $page_array = array();

                // First of all, get the request uri...
                $script_name = (!empty($_SERVER['PHP_SELF'])) ? $_SERVER['PHP_SELF'] : getenv('PHP_SELF');
                $args = (!empty($_SERVER['QUERY_STRING'])) ? explode('&', $_SERVER['QUERY_STRING']) : explode('&', getenv('QUERY_STRING'));

                // If we are unable to get the script name we use REQUEST_URI as a failover and note it within the page array for easier support...
                if (!$script_name)
                {
                        $script_name = (!empty($_SERVER['REQUEST_URI'])) ? $_SERVER['REQUEST_URI'] : getenv('REQUEST_URI');
                        $script_name = (($pos = strpos($script_name, '?')) !== false) ? substr($script_name, 0, $pos) : $script_name;
                        $page_array['failover'] = 1;
                }

                // Replace backslashes and doubled slashes (could happen on some proxy setups)
                $script_name = str_replace(array('\\', '//'), '/', $script_name);

                // Now, remove the sid and let us get a clean query string...
                $use_args = array();

                // Since some browser do not encode correctly we need to do this with some "special" characters...
                // " -> %22, ' => %27, < -> %3C, > -> %3E
                $find = array('"', "'", '<', '>');
                $replace = array('%22', '%27', '%3C', '%3E');

                foreach ($args as $argument)
                {
                        if (strpos($argument, 'sid=') === 0)
                        {
                                continue;
                        }

                        $use_args[] = str_replace($find, $replace, $argument);
                }
                unset($args);

                // The following examples given are for an request uri of {path to the phpbb directory}/adm/index.php?i=10&b=2

                // The current query string
                $query_string = trim(implode('&', $use_args));

                // basenamed page name (for example: index.php)
                $page_name = basename($script_name);
                $page_name = urlencode(htmlspecialchars($page_name));

                // current directory within the phpBB root (for example: adm)
                $root_dirs = explode('/', str_replace('\\', '/', phpbb::$url->realpath(PHPBB_ROOT_PATH)));
                $page_dirs = explode('/', str_replace('\\', '/', phpbb::$url->realpath('./')));
                $intersection = array_intersect_assoc($root_dirs, $page_dirs);

                $root_dirs = array_diff_assoc($root_dirs, $intersection);
                $page_dirs = array_diff_assoc($page_dirs, $intersection);

                $page_dir = str_repeat('../', sizeof($root_dirs)) . implode('/', $page_dirs);

                if ($page_dir && substr($page_dir, -1, 1) == '/')
                {
                        $page_dir = substr($page_dir, 0, -1);
                }

                // Current page from phpBB root (for example: adm/index.php?i=10&b=2)
                $page = (($page_dir) ? $page_dir . '/' : '') . $page_name . (($query_string) ? "?$query_string" : '');

                // The script path from the webroot to the current directory (for example: /phpBB3/adm/) : always prefixed with / and ends in /
                $script_path = trim(str_replace('\\', '/', dirname($script_name)));

                // The script path from the webroot to the phpBB root (for example: /phpBB3/)
                $script_dirs = explode('/', $script_path);
                array_splice($script_dirs, -sizeof($page_dirs));
                $root_script_path = implode('/', $script_dirs) . (sizeof($root_dirs) ? '/' . implode('/', $root_dirs) : '');

                // We are on the base level (phpBB root == webroot), lets adjust the variables a bit...
                if (!$root_script_path)
                {
                        $root_script_path = ($page_dir) ? str_replace($page_dir, '', $script_path) : $script_path;
                }

                $script_path .= (substr($script_path, -1, 1) == '/') ? '' : '/';
                $root_script_path .= (substr($root_script_path, -1, 1) == '/') ? '' : '/';

                $page_array += array(
                        'page_name'                     => $page_name,
                        'page_dir'                      => $page_dir,

                        'query_string'          => $query_string,
                        'script_path'           => str_replace(' ', '%20', htmlspecialchars($script_path)),
                        'root_script_path'      => str_replace(' ', '%20', htmlspecialchars($root_script_path)),

                        'page'                          => $page,
                        'forum'                         => request_var('f', 0),
                );

                return ($this->method_inject(__FUNCTION__, 'return')) ? $this->call_inject(__FUNCTION__, array('return', $page_array)) : $page_array;
        }

        /**
        * Get user agent string.
        *
        * @return string User agent, determined from $_SERVER['HTTP_USER_AGENT']. Specialchared.
        * @access protected
        */
        protected function get_browser()
        {
                return (!empty($_SERVER['HTTP_USER_AGENT'])) ? htmlspecialchars((string) $_SERVER['HTTP_USER_AGENT']) : '';
        }

        /**
        * Get current referer
        *
        * @return string Referer, determined from $_SERVER['HTTP_REFERER']. Specialchared.
        * @access protected
        */
        protected function get_referer()
        {
                return (!empty($_SERVER['HTTP_REFERER'])) ? htmlspecialchars((string) $_SERVER['HTTP_REFERER']) : '';
        }

        /**
        * Get server port
        *
        * @return int Sertver port, determined from $_SERVER/$_ENV['SERVER_PORT'].
        * @access protected
        */
        protected function get_port()
        {
                return (!empty($_SERVER['SERVER_PORT'])) ? (int) $_SERVER['SERVER_PORT'] : (int) getenv('SERVER_PORT');
        }

        /**
        * Get forwarded-for string.
        * If the forwarded for check is enabled in phpBB the ip's are checked for valid data and invalid data being removed.
        *
        * @return string Forwarded-for string, determined from $_SERVER['HTTP_X_FORWARDED_FOR'].
        * @access protected
        */
        protected function get_forwarded_for()
        {
                $forwarded_for = (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) ? (string) $_SERVER['HTTP_X_FORWARDED_FOR'] : '';

                // if the forwarded for header shall be checked we have to validate its contents
                if (phpbb::$config['forwarded_for_check'])
                {
                        $forwarded_for = preg_replace('#, +#', ', ', $forwarded_for);

                        // split the list of IPs
                        $ips = explode(', ', $forwarded_for);
                        foreach ($ips as $ip)
                        {
                                // check IPv4 first, the IPv6 is hopefully only going to be used very seldomly
                                if (!empty($ip) && !preg_match(get_preg_expression('ipv4'), $ip) && !preg_match(get_preg_expression('ipv6'), $ip))
                                {
                                        // contains invalid data, don't use the forwarded for header
                                        return '';
                                }
                        }
                }
                else
                {
                        return '';
                }
        }

        /**
        * Get remote ip
        *
        * @return string Remote IP, determined from $_SERVER['REMOTE_ADDR']. Specialchared.
        * @access protected
        */
        protected function get_ip()
        {
                return (!empty($_SERVER['REMOTE_ADDR'])) ? htmlspecialchars($_SERVER['REMOTE_ADDR']) : '';
        }

        /**
        * Get server load.
        *
        * Server load is retrieved if load limitation is enabled in phpBB and server supports {@link sys_getloadavg() sys_getloadavg}
        * or file /proc/loadavg exists on the server.
        *
        * @return double Server load.
        * @access protected
        */
        protected function get_load()
        {
                $load = false;

                // Load limit check (if applicable)
                if (phpbb::$config['limit_load'] || phpbb::$config['limit_search_load'])
                {
                        if ((function_exists('sys_getloadavg') && $load = sys_getloadavg()) || ($load = explode(' ', @file_get_contents('/proc/loadavg'))))
                        {
                                $load = array_slice($load, 0, 1);
                                $load = floatval($load[0]);
                        }
                        else
                        {
                                set_config('limit_load', '0');
                                set_config('limit_search_load', '0');
                        }
                }

                return $load;
        }

        /**
        * Get current request method.
        *
        * @return string Request method, determined from $_SERVER['REQUEST_METHOD']. Specialchared, lowercase.
        * @access protected
        */
        protected function get_request_method()
        {
                return (isset($_SERVER['REQUEST_METHOD'])) ? strtolower(htmlspecialchars((string) $_SERVER['REQUEST_METHOD'])) : '';
        }
}

?>