index.php

<?php

/**
 * This, as you have probably guessed, is the crux on which SMF functions.
 * Everything should start here, so all the setup and security is done
 * properly.  The most interesting part of this file is the action array in
 * the smf_main() function.  It is formatted as so:
 * 	'action-in-url' => array('Source-File.php', 'FunctionToCall'),
 *
 * Then, you can access the FunctionToCall() function from Source-File.php
 * with the URL index.php?action=action-in-url.  Relatively simple, no?
 *
 * Simple Machines Forum (SMF)
 *
 * @package SMF
 * @author Simple Machines https://www.simplemachines.org
 * @copyright 2020 Simple Machines and individual contributors
 * @license https://www.simplemachines.org/about/smf/license.php BSD
 *
 * @version 2.1 RC2
 */

// Get everything started up...
define('SMF', 1);
define('SMF_VERSION', '2.1 RC2');
define('SMF_FULL_VERSION', 'SMF ' . SMF_VERSION);
define('SMF_SOFTWARE_YEAR', '2020');

define('JQUERY_VERSION', '3.4.1');
define('POSTGRE_TITLE', 'PostgreSQL');
define('MYSQL_TITLE', 'MySQL');
define('SMF_USER_AGENT', 'Mozilla/5.0 (' . php_uname('s') . ' ' . php_uname('m') . ') AppleWebKit/605.1.15 (KHTML, like Gecko)  SMF/' . strtr(SMF_VERSION, ' ', '.'));

if (!defined('TIME_START'))
	define('TIME_START', microtime(true));

// If anything goes wrong loading Settings.php, make sure the admin knows it.
error_reporting(E_ALL);

// This makes it so headers can be sent!
ob_start();

// Do some cleaning, just in case.
foreach (array('db_character_set', 'cachedir') as $variable)
	unset($GLOBALS[$variable]);

// Load the settings...
require_once(dirname(__FILE__) . '/Settings.php');

// Devs want all error messages, but others don't.
error_reporting(!empty($db_show_debug) ? E_ALL : E_ALL & ~E_DEPRECATED);

// Ensure there are no trailing slashes in these variables.
foreach (array('boardurl', 'boarddir', 'sourcedir', 'packagesdir', 'taskddir', 'cachedir') as $variable)
	if (!empty($GLOBALS[$variable]))
		$GLOBALS[$variable] = rtrim($GLOBALS[$variable], "\\/");

// Make absolutely sure the cache directory is defined and writable.
if (empty($cachedir) || !is_dir($cachedir) || !is_writable($cachedir))
{
	if (is_dir($boarddir . '/cache') && is_writable($boarddir . '/cache'))
		$cachedir = $boarddir . '/cache';
	else
	{
		$cachedir = sys_get_temp_dir() . '/smf_cache_' . md5($boarddir);
		@mkdir($cachedir, 0750);
	}
}

// Without those we can't go anywhere
require_once($sourcedir . '/QueryString.php');
require_once($sourcedir . '/Subs.php');
require_once($sourcedir . '/Subs-Auth.php');
require_once($sourcedir . '/Errors.php');
require_once($sourcedir . '/Load.php');

// If $maintenance is set specifically to 2, then we're upgrading or something.
if (!empty($maintenance) &&  2 === $maintenance)
	display_maintenance_message();

// Create a variable to store some SMF specific functions in.
$smcFunc = array();

// Initiate the database connection and define some database functions to use.
loadDatabase();

// Load the settings from the settings table, and perform operations like optimizing.
$context = array();
reloadSettings();
// Clean the request variables, add slashes, etc.
cleanRequest();

// Seed the random generator.
if (empty($modSettings['rand_seed']) || mt_rand(1, 250) == 69)
	smf_seed_generator();

// Before we get carried away, are we doing a scheduled task? If so save CPU cycles by jumping out!
if (isset($_GET['scheduled']))
{
	require_once($sourcedir . '/ScheduledTasks.php');
	AutoTask();
}

// And important includes.
require_once($sourcedir . '/Session.php');
require_once($sourcedir . '/Logging.php');
require_once($sourcedir . '/Security.php');
require_once($sourcedir . '/Class-BrowserDetect.php');

// Check if compressed output is enabled, supported, and not already being done.
if (!empty($modSettings['enableCompressedOutput']) && !headers_sent())
{
	// If zlib is being used, turn off output compression.
	if (ini_get('zlib.output_compression') >= 1 || ini_get('output_handler') == 'ob_gzhandler')
		$modSettings['enableCompressedOutput'] = '0';
	else
	{
		ob_end_clean();
		ob_start('ob_gzhandler');
	}
}

/**
 * An autoloader for certain classes.
 *
 * @param string $class The fully-qualified class name.
 */
spl_autoload_register(function ($class) use ($sourcedir)
{
	$classMap = array(
		'ReCaptcha\\' => 'ReCaptcha/',
		'MatthiasMullie\\Minify\\' => 'minify/src/',
		'MatthiasMullie\\PathConverter\\' => 'minify/path-converter/src/',
	);

	// Do any third-party scripts want in on the fun?
	call_integration_hook('integrate_autoload', array(&$classMap));

	foreach ($classMap as $prefix => $dirName)
	{
		// does the class use the namespace prefix?
		$len = strlen($prefix);
		if (strncmp($prefix, $class, $len) !== 0)
		{
			continue;
		}

		// get the relative class name
		$relativeClass = substr($class, $len);

		// replace the namespace prefix with the base directory, replace namespace
		// separators with directory separators in the relative class name, append
		// with .php
		$fileName = $dirName . strtr($relativeClass, '\\', '/') . '.php';

		// if the file exists, require it
		if (file_exists($fileName = $sourcedir . '/' . $fileName))
		{
			require_once $fileName;

			return;
		}
	}
});

// Register an error handler.
set_error_handler('smf_error_handler');

// Start the session. (assuming it hasn't already been.)
loadSession();

// What function shall we execute? (done like this for memory's sake.)
call_user_func(smf_main());

// Call obExit specially; we're coming from the main area ;).
obExit(null, null, true);

/**
 * The main dispatcher.
 * This delegates to each area.
 *
 * @return array|string|void An array containing the file to include and name of function to call, the name of a function to call or dies with a fatal_lang_error if we couldn't find anything to do.
 */
function smf_main()
{
	global $modSettings, $settings, $user_info, $board, $topic;
	global $board_info, $maintenance, $sourcedir, $should_log;

	// Special case: session keep-alive, output a transparent pixel.
	if (isset($_GET['action']) && $_GET['action'] == 'keepalive')
	{
		header('content-type: image/gif');
		die("\x47\x49\x46\x38\x39\x61\x01\x00\x01\x00\x80\x00\x00\x00\x00\x00\x00\x00\x00\x21\xF9\x04\x01\x00\x00\x00\x00\x2C\x00\x00\x00\x00\x01\x00\x01\x00\x00\x02\x02\x44\x01\x00\x3B");
	}

	// We should set our security headers now.
	frameOptionsHeader();

	// Load the user's cookie (or set as guest) and load their settings.
	loadUserSettings();

	// Load the current board's information.
	loadBoard();

	// Load the current user's permissions.
	loadPermissions();

	// Attachments don't require the entire theme to be loaded.
	if (isset($_REQUEST['action']) && $_REQUEST['action'] == 'dlattach' && empty($maintenance))
		detectBrowser();
	// Load the current theme.  (note that ?theme=1 will also work, may be used for guest theming.)
	else
		loadTheme();

	// Check if the user should be disallowed access.
	is_not_banned();

	// If we are in a topic and don't have permission to approve it then duck out now.
	if (!empty($topic) && empty($board_info['cur_topic_approved']) && !allowedTo('approve_posts') && ($user_info['id'] != $board_info['cur_topic_starter'] || $user_info['is_guest']))
		fatal_lang_error('not_a_topic', false);

	// Do some logging, unless this is an attachment, avatar, toggle of editor buttons, theme option, XML feed, popup, etc.
	$no_stat_actions = array(
		'about:unknown' => true,
		'clock' => true,
		'dlattach' => true,
		'findmember' => true,
		'helpadmin' => true,
		'jsoption' => true,
		'likes' => true,
		'loadeditorlocale' => true,
		'modifycat' => true,
		'pm' => array('sa' => array('popup')),
		'profile' => array('area' => array('popup', 'alerts_popup')),
		'requestmembers' => true,
		'smstats' => true,
		'suggest' => true,
		'verificationcode' => true,
		'viewquery' => true,
		'viewsmfile' => true,
		'xmlhttp' => true,
		'.xml' => true,
	);
	call_integration_hook('integrate_pre_log_stats', array(&$no_stat_actions));

	$should_log = true;
	if (isset($_REQUEST['action']) && isset($no_stat_actions[$_REQUEST['action']]))
	{
		if (is_array($no_stat_actions[$_REQUEST['action']]))
		{
			foreach ($no_stat_actions[$_REQUEST['action']] as $subtype => $subnames)
			{
				if (isset($_REQUEST[$subtype]) && in_array($_REQUEST[$subtype], $subnames))
				{
					$should_log = false;
					break;
				}
			}
		}
		else
			$should_log = empty($no_stat_actions[$_REQUEST['action']]);
	}
	if ($should_log)
	{
		// Log this user as online.
		writeLog();

		// Track forum statistics and hits...?
		if (!empty($modSettings['hitStats']))
			trackStats(array('hits' => '+'));
	}
	unset($no_stat_actions);

	// Make sure that our scheduled tasks have been running as intended
	check_cron();

	// Is the forum in maintenance mode? (doesn't apply to administrators.)
	if (!empty($maintenance) && !allowedTo('admin_forum'))
	{
		// You can only login.... otherwise, you're getting the "maintenance mode" display.
		if (isset($_REQUEST['action']) && (in_array($_REQUEST['action'], array('login2', 'logintfa', 'logout'))))
		{
			require_once($sourcedir . '/LogInOut.php');
			return ($_REQUEST['action'] == 'login2' ? 'Login2' : ($_REQUEST['action'] == 'logintfa' ? 'LoginTFA' : 'Logout'));
		}
		// Don't even try it, sonny.
		else
			return 'InMaintenance';
	}
	// If guest access is off, a guest can only do one of the very few following actions.
	elseif (empty($modSettings['allow_guestAccess']) && $user_info['is_guest'] && (!isset($_REQUEST['action']) || !in_array($_REQUEST['action'], array('coppa', 'login', 'login2', 'logintfa', 'reminder', 'activate', 'help', 'helpadmin', 'smstats', 'verificationcode', 'signup', 'signup2'))))
		return 'KickGuest';
	elseif (empty($_REQUEST['action']))
	{
		// Action and board are both empty... BoardIndex! Unless someone else wants to do something different.
		if (empty($board) && empty($topic))
		{
			if (!empty($modSettings['integrate_default_action']))
			{
				$defaultAction = explode(',', $modSettings['integrate_default_action']);

				// Sorry, only one default action is needed.
				$defaultAction = $defaultAction[0];

				$call = call_helper($defaultAction, true);

				if (!empty($call))
					return $call;
			}

			// No default action huh? then go to our good old BoardIndex.
			else
			{
				require_once($sourcedir . '/BoardIndex.php');

				return 'BoardIndex';
			}
		}

		// Topic is empty, and action is empty.... MessageIndex!
		elseif (empty($topic))
		{
			require_once($sourcedir . '/MessageIndex.php');
			return 'MessageIndex';
		}

		// Board is not empty... topic is not empty... action is empty.. Display!
		else
		{
			require_once($sourcedir . '/Display.php');
			return 'Display';
		}
	}

	// Here's the monstrous $_REQUEST['action'] array - $_REQUEST['action'] => array($file, $function).
	$actionArray = array(
		'activate' => array('Register.php', 'Activate'),
		'admin' => array('Admin.php', 'AdminMain'),
		'announce' => array('Post.php', 'AnnounceTopic'),
		'attachapprove' => array('ManageAttachments.php', 'ApproveAttach'),
		'buddy' => array('Subs-Members.php', 'BuddyListToggle'),
		'calendar' => array('Calendar.php', 'CalendarMain'),
		'clock' => array('Calendar.php', 'clock'),
		'coppa' => array('Register.php', 'CoppaForm'),
		'credits' => array('Who.php', 'Credits'),
		'deletemsg' => array('RemoveTopic.php', 'DeleteMessage'),
		'dlattach' => array('ShowAttachments.php', 'showAttachment'),
		'editpoll' => array('Poll.php', 'EditPoll'),
		'editpoll2' => array('Poll.php', 'EditPoll2'),
		'findmember' => array('Subs-Auth.php', 'JSMembers'),
		'groups' => array('Groups.php', 'Groups'),
		'help' => array('Help.php', 'ShowHelp'),
		'helpadmin' => array('Help.php', 'ShowAdminHelp'),
		'jsmodify' => array('Post.php', 'JavaScriptModify'),
		'jsoption' => array('Themes.php', 'SetJavaScript'),
		'likes' => array('Likes.php', 'Likes::call#'),
		'loadeditorlocale' => array('Subs-Editor.php', 'loadLocale'),
		'lock' => array('Topic.php', 'LockTopic'),
		'lockvoting' => array('Poll.php', 'LockVoting'),
		'login' => array('LogInOut.php', 'Login'),
		'login2' => array('LogInOut.php', 'Login2'),
		'logintfa' => array('LogInOut.php', 'LoginTFA'),
		'logout' => array('LogInOut.php', 'Logout'),
		'markasread' => array('Subs-Boards.php', 'MarkRead'),
		'mergetopics' => array('SplitTopics.php', 'MergeTopics'),
		'mlist' => array('Memberlist.php', 'Memberlist'),
		'moderate' => array('ModerationCenter.php', 'ModerationMain'),
		'modifycat' => array('ManageBoards.php', 'ModifyCat'),
		'movetopic' => array('MoveTopic.php', 'MoveTopic'),
		'movetopic2' => array('MoveTopic.php', 'MoveTopic2'),
		'notifyannouncements' => array('Notify.php', 'AnnouncementsNotify'),
		'notifyboard' => array('Notify.php', 'BoardNotify'),
		'notifytopic' => array('Notify.php', 'TopicNotify'),
		'pm' => array('PersonalMessage.php', 'MessageMain'),
		'post' => array('Post.php', 'Post'),
		'post2' => array('Post.php', 'Post2'),
		'printpage' => array('Printpage.php', 'PrintTopic'),
		'profile' => array('Profile.php', 'ModifyProfile'),
		'quotefast' => array('Post.php', 'QuoteFast'),
		'quickmod' => array('MessageIndex.php', 'QuickModeration'),
		'quickmod2' => array('Display.php', 'QuickInTopicModeration'),
		'recent' => array('Recent.php', 'RecentPosts'),
		'reminder' => array('Reminder.php', 'RemindMe'),
		'removepoll' => array('Poll.php', 'RemovePoll'),
		'removetopic2' => array('RemoveTopic.php', 'RemoveTopic2'),
		'reporttm' => array('ReportToMod.php', 'ReportToModerator'),
		'requestmembers' => array('Subs-Auth.php', 'RequestMembers'),
		'restoretopic' => array('RemoveTopic.php', 'RestoreTopic'),
		'search' => array('Search.php', 'PlushSearch1'),
		'search2' => array('Search.php', 'PlushSearch2'),
		'sendactivation' => array('Register.php', 'SendActivation'),
		'signup' => array('Register.php', 'Register'),
		'signup2' => array('Register.php', 'Register2'),
		'smstats' => array('Stats.php', 'SMStats'),
		'suggest' => array('Subs-Editor.php', 'AutoSuggestHandler'),
		'spellcheck' => array('Subs-Post.php', 'SpellCheck'),
		'splittopics' => array('SplitTopics.php', 'SplitTopics'),
		'stats' => array('Stats.php', 'DisplayStats'),
		'sticky' => array('Topic.php', 'Sticky'),
		'theme' => array('Themes.php', 'ThemesMain'),
		'trackip' => array('Profile-View.php', 'trackIP'),
		'about:unknown' => array('Likes.php', 'BookOfUnknown'),
		'unread' => array('Recent.php', 'UnreadTopics'),
		'unreadreplies' => array('Recent.php', 'UnreadTopics'),
		'uploadAttach' => array('Attachments.php', 'Attachments::call#'),
		'verificationcode' => array('Register.php', 'VerificationCode'),
		'viewprofile' => array('Profile.php', 'ModifyProfile'),
		'vote' => array('Poll.php', 'Vote'),
		'viewquery' => array('ViewQuery.php', 'ViewQuery'),
		'viewsmfile' => array('Admin.php', 'DisplayAdminFile'),
		'who' => array('Who.php', 'Who'),
		'.xml' => array('News.php', 'ShowXmlFeed'),
		'xmlhttp' => array('Xml.php', 'XMLhttpMain'),
	);

	// Allow modifying $actionArray easily.
	call_integration_hook('integrate_actions', array(&$actionArray));

	// Get the function and file to include - if it's not there, do the board index.
	if (!isset($_REQUEST['action']) || !isset($actionArray[$_REQUEST['action']]))
	{
		// Catch the action with the theme?
		if (!empty($settings['catch_action']))
		{
			require_once($sourcedir . '/Themes.php');
			return 'WrapAction';
		}

		if (!empty($modSettings['integrate_fallback_action']))
		{
			$fallbackAction = explode(',', $modSettings['integrate_fallback_action']);

			// Sorry, only one fallback action is needed.
			$fallbackAction = $fallbackAction[0];

			$call = call_helper($fallbackAction, true);

			if (!empty($call))
				return $call;
		}

		// No fallback action, huh?
		else
		{
			fatal_lang_error('not_found', false, array(), 404);
		}
	}

	// Otherwise, it was set - so let's go to that action.
	if (!empty($actionArray[$_REQUEST['action']][0]))
		require_once($sourcedir . '/' . $actionArray[$_REQUEST['action']][0]);

	// Do the right thing.
	return call_helper($actionArray[$_REQUEST['action']][1], true);
}

?>