/include/functions.php

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<?php

/**
 * Copyright (C) 2008-2010 FluxBB
 * based on code by Rickard Andersson copyright (C) 2002-2008 PunBB
 * License: http://www.gnu.org/licenses/gpl.html GPL version 2 or higher
 */

//
// Return current timestamp (with microseconds) as a float
//
function get_microtime()
{
	list($usec, $sec) = explode(' ', microtime());
	return ((float)$usec + (float)$sec);
}

//Real token generation.
//This has been beefed up a little, by enhancing it's number of choices.
//This takes it's "total number of possible combinations" from '751616304549', to '8.66106956337463e+24'
//A brute force attack versus a server that will delay them is just not feasible at that stage.
//It would be easier to break into the database.
function gen_token() {
	$token = '';
	$chars = array(
			'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
			'a', 'b', 'c', 'd', 'e', 'f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z',
			'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'
		);
	
	for ($i = 0; $i < 32; $i++) {
		$token .= $chars[rand(0, count($chars)-1)];
	} //End 'i' for loop.
	
	return $token;
	
} //End gen_token().

//
// Cookie stuff!
//
function check_cookie(&$pun_user)
{
	global $db, $db_type, $pun_config, $cookie_seed;
	
	//Create a cookie name that can't clash in anyway, just to be one the safe side.
	//(Browsers *should* isolate the cookie per domain, but either way I don't want duplicate cookie names.)
	$cookie_name = str_replace('=', '', base64_encode($_SERVER['SERVER_NAME']));

	$now = gmmktime();
	$earlier = $now - $pun_config['session_length'];
	$much_earlier = $now - 2629743;
	
	$cookie = array();
	$matches = array();
	
	if (isset($_SERVER['HTTP_EVE_TRUSTED'])) {
		$_SESSION['igb'] = true;
	} else {
		$_SESSION['igb'] = false;
	} //End if - else.

    //Lets pull our session data out.
    if (isset($_COOKIE[$cookie_name]) && preg_match('/^(\d+)\:([0-9a-zA-Z]{32}):([0-9a-fA-F]{32})$/', $_COOKIE[$cookie_name], $matches)) {
        $cookie['user_id'] = intval($matches[1]);
        $cookie['token'] = $matches[2];
        $cookie['hash'] = $matches[3];
        $cookie['remember'] = 1;
    } else if (isset($_SESSION[$cookie_name]) && preg_match('/^(\d+)\:([0-9a-zA-Z]{32}):([0-9a-fA-F]{32})$/', $_SESSION[$cookie_name], $matches)) {
    	$cookie['user_id'] = intval($matches[1]);
        $cookie['token'] = $matches[2];
        $cookie['hash'] = $matches[3];
    } //End if.
    
    if (!empty($cookie) && isset($cookie['user_id'])) {
    	
    	if (md5($cookie['user_id'].$cookie_seed.$cookie['token']) != $cookie['hash']) {
    		if (defined('PUN_DEBUG')) {
    			error('Hash mismatch.', __FILE__, __LINE__, $db->error());
    		} //End if.
        	unset($_SESSION[$cookie_name]);
        	sleep(3);
        	set_default_user();
        	return; //The session has been messed with, abort!
    	} //End if.
    	
		$result = $db->query('
			SELECT
				sess.*,
				c.*,
				sc.*,
				u.*,
				g.*,
				o.logged,
				o.idle
			FROM
				'.$db->prefix.'session AS sess
			INNER JOIN
				'.$db->prefix.'users AS u
			ON
				sess.user_id=u.id
			INNER JOIN
				'.$db->prefix.'groups AS g
			ON
				u.group_id=g.g_id
			LEFT JOIN
				'.$db->prefix.'online AS o
			ON
				o.user_id=u.id
			LEFT JOIN
				'.$db->prefix.'api_selected_char AS sc
			ON
				u.id=sc.user_id
			LEFT JOIN
				'.$db->prefix.'api_characters AS c
			ON
				sc.character_id=c.character_id
			WHERE
				u.id='.intval($cookie['user_id']))
		or error('Unable to fetch user information', __FILE__, __LINE__, $db->error());
        
        if ($db->num_rows($result) != 1) {
    		if (defined('PUN_DEBUG')) {
    			error('No user found.', __FILE__, __LINE__, $db->error());
    		} //End if.
        	unset($_SESSION[$cookie_name]);
        	set_default_user();
        	sleep(3);
        	return; //Chances are they have no active session.
        } //End if.
        
        $pun_user = $db->fetch_assoc($result);
        
        if ($pun_user['token'] != $cookie['token']) {
    		if (defined('PUN_DEBUG')) {
    			error('Token mismatch: '.$pun_user['token'].', '.$cookie['token'], __FILE__, __LINE__, $db->error());
    		} //End if.
        	//Even though this failed, because of the possibility of external tomfoolery, we won't remove the session.
        	if (isset($cookie['remember'])) {
        		$expire = $now + 31536000; // The cookie expires after a year
        		forum_setcookie($cookie_name, pun_hash(uniqid(rand(), true)), $expire);
        	} //End if.
        	unset($_SESSION[$cookie_name]);
        	set_default_user();
        	sleep(3);
        	return; //Trying to access from an old session, or they are evil!
        } //End if.
        
        //Is the stamp old or are they using a session cookie from a different IP?
        if ($now > ($pun_user['stamp'] + $pun_user['length']) || (($pun_user['ip'] != $_SERVER['REMOTE_ADDR']) && !isset($cookie['remember']))) {
    		if (defined('PUN_DEBUG')) {
    			error('IP or stamp mismatch.', __FILE__, __LINE__, $db->error());
    		} //End if.
        	$db->query("DELETE FROM ".$db->prefix."session WHERE user_id=".$pun_user['id']); //Get rid of the old session.
        	if (isset($cookie['remember'])) {
        		$expire = $now + 31536000; // The cookie expires after a year
        		forum_setcookie($cookie_name, pun_hash(uniqid(rand(), true)), $expire);
        	} //End if.
        	unset($_SESSION[$cookie_name]);
        	set_default_user();
        	return;
        } //End if.
        
        //If they got this far, they provided a valid token with a valid user_id.
        $token = $pun_user['token'];
        
        //Lets update all our tracking bits.
        $db->query("UPDATE ".$db->prefix."session SET stamp=".$now.", length=".((isset($cookie['remember'])) ? 2629743 : $pun_config['session_length'])." WHERE user_id=".$pun_user['id']);
		
		if (isset($cookie['remember']) && !isset($_SESSION['remember']) && $pun_config['o_regen_token'] == '1') {
			//Let's generate a new token if they got here via a cookie login that doesn't have a session attached to it.
			$_SESSION['remember'] = 1;
			$token = gen_token();
			$pun_user['token'] = $token;
			$db->query("UPDATE ".$db->prefix."session SET token='".$token."' WHERE user_id=".$pun_user['id']);
		} else if (isset($cookie['remember'])) {
			$_SESSION['remember'] = 1;
		} //End if - else.

		// Send a new, updated cookie with a new expiration timestamp
		if (isset($cookie['remember'])) {
			forum_setcookie($cookie_name, $pun_user['id'].':'.$token.':'.md5($pun_user['id'].$cookie_seed.$token), $now+2629743); //Expire the cookie in 1 month.
		} //End if - else.
		
		//Update the PHP Session.
		$_SESSION[$cookie_name] = $pun_user['id'].':'.$token.':'.md5($pun_user['id'].$cookie_seed.$token);

		// Set a default language if the user selected language no longer exists
		if (!file_exists(PUN_ROOT.'lang/'.$pun_user['language']))
			$pun_user['language'] = $pun_config['o_default_lang'];

		// Set a default style if the user selected style no longer exists
		if (!file_exists(PUN_ROOT.'style/'.$pun_user['style'].'.css'))
			$pun_user['style'] = $pun_config['o_default_style'];

		if (!$pun_user['disp_topics'])
			$pun_user['disp_topics'] = $pun_config['o_disp_topics_default'];
		if (!$pun_user['disp_posts'])
			$pun_user['disp_posts'] = $pun_config['o_disp_posts_default'];

		// Define this if you want this visit to affect the online list and the users last visit data
		if (!defined('PUN_QUIET_VISIT'))
		{
			// Update the online list
			if (!$pun_user['logged'])
			{
				$pun_user['logged'] = $now;

				// With MySQL/MySQLi/SQLite, REPLACE INTO avoids a user having two rows in the online table
				switch ($db_type)
				{
					case 'mysql':
					case 'mysqli':
					case 'mysql_innodb':
					case 'mysqli_innodb':
					case 'sqlite':
						$db->query('REPLACE INTO '.$db->prefix.'online (user_id, ident, logged) VALUES('.$pun_user['id'].', \''.$db->escape($pun_user['username']).'\', '.$pun_user['logged'].')') or error('Unable to insert into online list', __FILE__, __LINE__, $db->error());
						break;

					default:
						$db->query('INSERT INTO '.$db->prefix.'online (user_id, ident, logged) SELECT '.$pun_user['id'].', \''.$db->escape($pun_user['username']).'\', '.$pun_user['logged'].' WHERE NOT EXISTS (SELECT 1 FROM '.$db->prefix.'online WHERE user_id='.$pun_user['id'].')') or error('Unable to insert into online list', __FILE__, __LINE__, $db->error());
						break;
				}

				// Reset tracked topics
				set_tracked_topics(null);
			}
			else
			{
				// Special case: We've timed out, but no other user has browsed the forums since we timed out
				if ($pun_user['logged'] < ($now-$pun_config['o_timeout_visit']))
				{
					$db->query('UPDATE '.$db->prefix.'users SET last_visit='.$pun_user['logged'].' WHERE id='.$pun_user['id']) or error('Unable to update user visit data', __FILE__, __LINE__, $db->error());
					$pun_user['last_visit'] = $pun_user['logged'];
				}

				$idle_sql = ($pun_user['idle'] == '1') ? ', idle=0' : '';
				$db->query('UPDATE '.$db->prefix.'online SET logged='.$now.$idle_sql.' WHERE user_id='.$pun_user['id']) or error('Unable to update online list', __FILE__, __LINE__, $db->error());

				// Update tracked topics with the current expire time
				if (isset($_COOKIE[$cookie_name.'_track']))
					forum_setcookie($cookie_name.'_track', $_COOKIE[$cookie_name.'_track'], $now + $pun_config['o_timeout_visit']);
			}
		}
		else
		{
			if (!$pun_user['logged'])
				$pun_user['logged'] = $pun_user['last_visit'];
		}

		$pun_user['is_guest'] = false;
		$pun_user['is_admmod'] = $pun_user['g_id'] == PUN_ADMIN || $pun_user['g_moderator'] == '1';
		
		/* EVE-BB Multi-group support.*/
		//We only look at their other groups if they aren't set as the purge group as primary.
		if ($pun_user['g_id'] != $pun_config['o_eve_restricted_group']) {
			$sql = "SELECT group_id FROM ".$db->prefix."groups_users WHERE user_id=".$pun_user['id'];
			$result = $db->query($sql) or error('Unable to fetch group list', __FILE__, __LINE__, $db->error());
			
			$pun_user['group_ids'] = array();
			
			while ($row = $db->fetch_assoc($result)) {
				$pun_user['group_ids'][] = $row['group_id'];
				if ($row['group_id'] == PUN_ADMIN) {
					$pun_user['is_admmod'] = true;
					$pun_user['g_id'] = PUN_ADMIN;
				} else if ($row['group_id'] == PUN_MOD) {
					$pun_user['is_admmod'] = true;
				} //End if - elseif.
			} //End while loop.
		} //End if.
		/* EVE-BB Multi-group support.*/
	} else {
		set_default_user();
	} //End if - else.
}


//
// Converts the CDATA end sequence ]]> into ]]&gt;
//
function escape_cdata($str)
{
	return str_replace(']]>', ']]&gt;', $str);
}


//
// Authenticates the provided username and password against the user database
// $user can be either a user ID (integer) or a username (string)
// $password can be either a plaintext password or a password hash including salt ($password_is_hash must be set accordingly)
//
function authenticate_user($user, $password, $password_is_hash = false)
{
	global $db, $pun_user;

	// Check if there's a user matching $user and $password
	$result = $db->query('SELECT u.*, g.*, o.logged, o.idle FROM '.$db->prefix.'users AS u INNER JOIN '.$db->prefix.'groups AS g ON g.g_id=u.group_id LEFT JOIN '.$db->prefix.'online AS o ON o.user_id=u.id WHERE '.(is_int($user) ? 'u.id='.intval($user) : 'u.username=\''.$db->escape($user).'\'')) or error('Unable to fetch user info', __FILE__, __LINE__, $db->error());
	$pun_user = $db->fetch_assoc($result);

	if (!isset($pun_user['id']) ||
		($password_is_hash && $password != $pun_user['password']) ||
		(!$password_is_hash && pun_hash($password) != $pun_user['password']))
		set_default_user();
	else
		$pun_user['is_guest'] = false;
}


//
// Try to determine the current URL
//
function get_current_url($max_length = 0)
{
	$protocol = get_current_protocol();
	$port = (isset($_SERVER['SERVER_PORT']) && (($_SERVER['SERVER_PORT'] != '80' && $protocol == 'http') || ($_SERVER['SERVER_PORT'] != '443' && $protocol == 'https')) && strpos($_SERVER['HTTP_HOST'], ':') === false) ? ':'.$_SERVER['SERVER_PORT'] : '';

	$url = urldecode($protocol.'://'.$_SERVER['HTTP_HOST'].$port.$_SERVER['REQUEST_URI']);

	if (strlen($url) <= $max_length || $max_length == 0)
		return $url;

	// We can't find a short enough url
	return null;
}

//
// Fetch the current protocol in use - http or https
//
function get_current_protocol()
{
    $protocol = 'http';
    // Check if the server is claiming to using HTTPS
    if (!empty($_SERVER['HTTPS']) && strtolower($_SERVER['HTTPS']) != 'off')
        $protocol = 'https';
    // If we are behind a reverse proxy try to decide which protocol it is using
    if (defined('FORUM_BEHIND_REVERSE_PROXY'))
    {
        // Check if we are behind a Microsoft based reverse proxy
        if (!empty($_SERVER['HTTP_FRONT_END_HTTPS']) && strtolower($_SERVER['HTTP_FRONT_END_HTTPS']) != 'off')
            $protocol = 'https';
        // Check if we're behind a "proper" reverse proxy, and what protocol it's using
        if (!empty($_SERVER['HTTP_X_FORWARDED_PROTO']))
            $protocol = strtolower($_SERVER['HTTP_X_FORWARDED_PROTO']);
    }
    return $protocol;
}
//
// Fetch the base_url, optionally support HTTPS and HTTP
//
function get_base_url($support_https = false)
{
    global $pun_config;
    static $base_url;
    if (!$support_https)
        return $pun_config['o_base_url'];
    if (!isset($base_url))
    {
        // Make sure we are using the correct protocol
        $base_url = str_replace(array('http://', 'https://'), get_current_protocol().'://', $pun_config['o_base_url']);
    }
    return $base_url;
}

//
// Fill $pun_user with default values (for guests)
//
function set_default_user()
{
	global $db, $db_type, $pun_user, $pun_config;

	$remote_addr = get_remote_address();

	// Fetch guest user
	$result = $db->query('SELECT u.*, g.*, o.logged, o.last_post, o.last_search FROM '.$db->prefix.'users AS u INNER JOIN '.$db->prefix.'groups AS g ON u.group_id=g.g_id LEFT JOIN '.$db->prefix.'online AS o ON o.ident=\''.$remote_addr.'\' WHERE u.id=1') or error('Unable to fetch guest information', __FILE__, __LINE__, $db->error());
	if (!$db->num_rows($result))
		exit('Unable to fetch guest information. The table \''.$db->prefix.'users\' must contain an entry with id = 1 that represents anonymous users.');

	$pun_user = $db->fetch_assoc($result);

	// Update online list
	if (!$pun_user['logged'])
	{
		$pun_user['logged'] = time();

		// With MySQL/MySQLi/SQLite, REPLACE INTO avoids a user having two rows in the online table
		switch ($db_type)
		{
			case 'mysql':
			case 'mysqli':
			case 'mysql_innodb':
			case 'mysqli_innodb':
			case 'sqlite':
				$db->query('REPLACE INTO '.$db->prefix.'online (user_id, ident, logged) VALUES(1, \''.$db->escape($remote_addr).'\', '.$pun_user['logged'].')') or error('Unable to insert into online list', __FILE__, __LINE__, $db->error());
				break;

			default:
				$db->query('INSERT INTO '.$db->prefix.'online (user_id, ident, logged) SELECT 1, \''.$db->escape($remote_addr).'\', '.$pun_user['logged'].' WHERE NOT EXISTS (SELECT 1 FROM '.$db->prefix.'online WHERE ident=\''.$db->escape($remote_addr).'\')') or error('Unable to insert into online list', __FILE__, __LINE__, $db->error());
				break;
		}
	}
	else
		$db->query('UPDATE '.$db->prefix.'online SET logged='.time().' WHERE ident=\''.$db->escape($remote_addr).'\'') or error('Unable to update online list', __FILE__, __LINE__, $db->error());

	$pun_user['disp_topics'] = $pun_config['o_disp_topics_default'];
	$pun_user['disp_posts'] = $pun_config['o_disp_posts_default'];
	$pun_user['timezone'] = $pun_config['o_default_timezone'];
	$pun_user['dst'] = $pun_config['o_default_dst'];
	$pun_user['language'] = $pun_config['o_default_lang'];
	$pun_user['style'] = $pun_config['o_default_style'];
	$pun_user['is_guest'] = true;
	$pun_user['is_admmod'] = false;
}

//
// SHA1 HMAC with PHP 4 fallback
//
function forum_hmac($data, $key, $raw_output = false)
{
    if (function_exists('hash_hmac'))
        return hash_hmac('sha1', $data, $key, $raw_output);
        
    // If key size more than blocksize then we hash it once
    if (strlen($key) > 64)
        $key = pack('H*', sha1($key)); // we have to use raw output here to match the standard
        
    // Ensure we're padded to exactly one block boundary
    $key = str_pad($key, 64, chr(0x00));
    $hmac_opad = str_repeat(chr(0x5C), 64);
    $hmac_ipad = str_repeat(chr(0x36), 64);
    
    // Do inner and outer padding
    for ($i = 0;$i < 64;$i++) {
        $hmac_opad[$i] = $hmac_opad[$i] ^ $key[$i];
        $hmac_ipad[$i] = $hmac_ipad[$i] ^ $key[$i];
    }
    
    // Finally, calculate the HMAC
    $hash = sha1($hmac_opad.pack('H*', sha1($hmac_ipad.$data)));
    
    // If we want raw output then we need to pack the final result
    if ($raw_output)
        $hash = pack('H*', $hash);
        
    return $hash;
}

//
// Set a cookie, FluxBB style!
// Wrapper for forum_setcookie
//
function pun_setcookie($user_id, $password_hash, $expire)
{
	global $cookie_seed;
	$cookie_name = base64_encode($_SERVER['SERVER_NAME']);

	forum_setcookie($cookie_name, $user_id.'|'.forum_hmac($password_hash, $cookie_seed.'_password_hash').'|'.$expire.'|'.forum_hmac($user_id.'|'.$expire, $cookie_seed.'_cookie_hash'), $expire);
}


//
// Set a cookie, FluxBB style!
//
function forum_setcookie($name, $value, $expire)
{
	global $cookie_path, $cookie_domain, $cookie_secure;

	// Enable sending of a P3P header
	header('P3P: CP="CUR ADM"');

	if (version_compare(PHP_VERSION, '5.2.0', '>=')) {
		setcookie($name, $value, $expire, $cookie_path, $cookie_domain, $cookie_secure, true);
	} else {
		setcookie($name, $value, $expire, $cookie_path.'; HttpOnly', $cookie_domain, $cookie_secure);
	} //End if - else.
}


//
// Check whether the connecting user is banned (and delete any expired bans while we're at it)
//
function check_bans()
{
	global $db, $pun_config, $lang_common, $pun_user, $pun_bans;

	// Admins and moderators aren't affected
	if ($pun_user['is_admmod'] || !$pun_bans)
		return;

	// Add a dot or a colon (depending on IPv4/IPv6) at the end of the IP address to prevent banned address
	// 192.168.0.5 from matching e.g. 192.168.0.50
	$user_ip = get_remote_address();
	$user_ip .= (strpos($user_ip, '.') !== false) ? '.' : ':';

	$bans_altered = false;
	$is_banned = false;

	foreach ($pun_bans as $cur_ban)
	{
		// Has this ban expired?
		if ($cur_ban['expire'] != '' && $cur_ban['expire'] <= time())
		{
			$db->query('DELETE FROM '.$db->prefix.'bans WHERE id='.$cur_ban['id']) or error('Unable to delete expired ban', __FILE__, __LINE__, $db->error());
			$bans_altered = true;
			continue;
		}

		if ($cur_ban['username'] != '' && utf8_strtolower($pun_user['username']) == utf8_strtolower($cur_ban['username']))
			$is_banned = true;

		if ($cur_ban['ip'] != '')
		{
			$cur_ban_ips = explode(' ', $cur_ban['ip']);

			$num_ips = count($cur_ban_ips);
			for ($i = 0; $i < $num_ips; ++$i)
			{
				// Add the proper ending to the ban
				if (strpos($user_ip, '.') !== false)
					$cur_ban_ips[$i] = $cur_ban_ips[$i].'.';
				else
					$cur_ban_ips[$i] = $cur_ban_ips[$i].':';

				if (substr($user_ip, 0, strlen($cur_ban_ips[$i])) == $cur_ban_ips[$i])
				{
					$is_banned = true;
					break;
				}
			}
		}

		if ($is_banned)
		{
			$db->query('DELETE FROM '.$db->prefix.'online WHERE ident=\''.$db->escape($pun_user['username']).'\'') or error('Unable to delete from online list', __FILE__, __LINE__, $db->error());
			message($lang_common['Ban message'].' '.(($cur_ban['expire'] != '') ? $lang_common['Ban message 2'].' '.strtolower(format_time($cur_ban['expire'], true)).'. ' : '').(($cur_ban['message'] != '') ? $lang_common['Ban message 3'].'<br /><br /><strong>'.pun_htmlspecialchars($cur_ban['message']).'</strong><br /><br />' : '<br /><br />').$lang_common['Ban message 4'].' <a href="mailto:'.$pun_config['o_admin_email'].'">'.$pun_config['o_admin_email'].'</a>.', true);
		}
	}

	// If we removed any expired bans during our run-through, we need to regenerate the bans cache
	if ($bans_altered)
	{
		if (!defined('FORUM_CACHE_FUNCTIONS_LOADED'))
			require PUN_ROOT.'include/cache.php';

		generate_bans_cache();
	}
}


//
// Check username
//
function check_username($username, $exclude_id = null)
{
	global $db, $pun_config, $errors, $lang_prof_reg, $lang_register, $lang_common, $pun_bans;

	// Convert multiple whitespace characters into one (to prevent people from registering with indistinguishable usernames)
	$username = preg_replace('#\s+#s', ' ', $username);

	// Validate username
	if (pun_strlen($username) < 2)
		$errors[] = $lang_prof_reg['Username too short'];
	else if (pun_strlen($username) > 25) // This usually doesn't happen since the form element only accepts 25 characters
		$errors[] = $lang_prof_reg['Username too long'];
	else if (!strcasecmp($username, 'Guest') || !strcasecmp($username, $lang_common['Guest']))
		$errors[] = $lang_prof_reg['Username guest'];
	else if (preg_match('/[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}/', $username) || preg_match('/((([0-9A-Fa-f]{1,4}:){7}[0-9A-Fa-f]{1,4})|(([0-9A-Fa-f]{1,4}:){6}:[0-9A-Fa-f]{1,4})|(([0-9A-Fa-f]{1,4}:){5}:([0-9A-Fa-f]{1,4}:)?[0-9A-Fa-f]{1,4})|(([0-9A-Fa-f]{1,4}:){4}:([0-9A-Fa-f]{1,4}:){0,2}[0-9A-Fa-f]{1,4})|(([0-9A-Fa-f]{1,4}:){3}:([0-9A-Fa-f]{1,4}:){0,3}[0-9A-Fa-f]{1,4})|(([0-9A-Fa-f]{1,4}:){2}:([0-9A-Fa-f]{1,4}:){0,4}[0-9A-Fa-f]{1,4})|(([0-9A-Fa-f]{1,4}:){6}((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b))|(([0-9A-Fa-f]{1,4}:){0,5}:((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b))|(::([0-9A-Fa-f]{1,4}:){0,5}((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b))|([0-9A-Fa-f]{1,4}::([0-9A-Fa-f]{1,4}:){0,5}[0-9A-Fa-f]{1,4})|(::([0-9A-Fa-f]{1,4}:){0,6}[0-9A-Fa-f]{1,4})|(([0-9A-Fa-f]{1,4}:){1,7}:))/', $username))
		$errors[] = $lang_prof_reg['Username IP'];
	else if ((strpos($username, '[') !== false || strpos($username, ']') !== false) && strpos($username, '\'') !== false && strpos($username, '"') !== false)
		$errors[] = $lang_prof_reg['Username reserved chars'];
	else if (preg_match('/(?:\[\/?(?:b|u|s|ins|del|em|i|h|colou?r|quote|code|img|url|email|list|\*)\]|\[(?:img|url|quote|list)=)/i', $username))
		$errors[] = $lang_prof_reg['Username BBCode'];

	// Check username for any censored words
	if ($pun_config['o_censoring'] == '1' && censor_words($username) != $username)
		$errors[] = $lang_register['Username censor'];

	// Check that the username (or a too similar username) is not already registered
	$query = ($exclude_id) ? ' AND id!='.$exclude_id : '';

	$result = $db->query('SELECT username FROM '.$db->prefix.'users WHERE (UPPER(username)=UPPER(\''.$db->escape($username).'\') OR UPPER(username)=UPPER(\''.$db->escape(ucp_preg_replace('/[^\p{L}\p{N}]/u', '', $username)).'\')) AND id>1'.$query) or error('Unable to fetch user info', __FILE__, __LINE__, $db->error());

	if ($db->num_rows($result))
	{
		$busy = $db->result($result);
		$errors[] = $lang_register['Username dupe 1'].' '.pun_htmlspecialchars($busy).'. '.$lang_register['Username dupe 2'];
	}

	// Check username for any banned usernames
	foreach ($pun_bans as $cur_ban)
	{
		if ($cur_ban['username'] != '' && utf8_strtolower($username) == utf8_strtolower($cur_ban['username']))
		{
			$errors[] = $lang_prof_reg['Banned username'];
			break;
		}
	}
}


//
// Update "Users online"
//
function update_users_online()
{
	global $db, $pun_config;

	$now = time();

	// Fetch all online list entries that are older than "o_timeout_online"
	$result = $db->query('SELECT user_id, ident, logged, idle FROM '.$db->prefix.'online WHERE logged<'.($now-$pun_config['o_timeout_online'])) or error('Unable to fetch old entries from online list', __FILE__, __LINE__, $db->error());
	while ($cur_user = $db->fetch_assoc($result))
	{
		// If the entry is a guest, delete it
		if ($cur_user['user_id'] == '1')
			$db->query('DELETE FROM '.$db->prefix.'online WHERE ident=\''.$db->escape($cur_user['ident']).'\'') or error('Unable to delete from online list', __FILE__, __LINE__, $db->error());
		else
		{
			// If the entry is older than "o_timeout_visit", update last_visit for the user in question, then delete him/her from the online list
			if ($cur_user['logged'] < ($now-$pun_config['o_timeout_visit']))
			{
				$db->query('UPDATE '.$db->prefix.'users SET last_visit='.$cur_user['logged'].' WHERE id='.$cur_user['user_id']) or error('Unable to update user visit data', __FILE__, __LINE__, $db->error());
				$db->query('DELETE FROM '.$db->prefix.'online WHERE user_id='.$cur_user['user_id']) or error('Unable to delete from online list', __FILE__, __LINE__, $db->error());
			}
			else if ($cur_user['idle'] == '0')
				$db->query('UPDATE '.$db->prefix.'online SET idle=1 WHERE user_id='.$cur_user['user_id']) or error('Unable to insert into online list', __FILE__, __LINE__, $db->error());
		}
	}
}

//
// Display the profile navigation menu
//
function generate_profile_menu($page = '')
{
	global $lang_profile, $pun_config, $pun_user, $id;

?>
<div id="profile" class="block2col">
	<div class="blockmenu">
		<h2><span><?php echo $lang_profile['Profile menu'] ?></span></h2>
		<div class="box">
			<div class="inbox">
				<ul>
					<li<?php if ($page == 'essentials') echo ' class="isactive"'; ?>><a href="profile.php?section=essentials&amp;id=<?php echo $id ?>"><?php echo $lang_profile['Section essentials'] ?></a></li>
					<li<?php if ($page == 'characters') echo ' class="isactive"'; ?>><a href="profile.php?section=characters&amp;id=<?php echo $id ?>"><?php echo $lang_profile['Section characters'] ?></a></li>
					<li<?php if ($page == 'personal') echo ' class="isactive"'; ?>><a href="profile.php?section=personal&amp;id=<?php echo $id ?>"><?php echo $lang_profile['Section personal'] ?></a></li>
					<li<?php if ($page == 'messaging') echo ' class="isactive"'; ?>><a href="profile.php?section=messaging&amp;id=<?php echo $id ?>"><?php echo $lang_profile['Section messaging'] ?></a></li>
<?php if ($pun_config['o_avatars'] == '1' || $pun_config['o_signatures'] == '1'): ?>					<li<?php if ($page == 'personality') echo ' class="isactive"'; ?>><a href="profile.php?section=personality&amp;id=<?php echo $id ?>"><?php echo $lang_profile['Section personality'] ?></a></li>
<?php endif; ?>					<li<?php if ($page == 'display') echo ' class="isactive"'; ?>><a href="profile.php?section=display&amp;id=<?php echo $id ?>"><?php echo $lang_profile['Section display'] ?></a></li>
					<li<?php if ($page == 'privacy') echo ' class="isactive"'; ?>><a href="profile.php?section=privacy&amp;id=<?php echo $id ?>"><?php echo $lang_profile['Section privacy'] ?></a></li>
<?php if ($pun_user['g_id'] == PUN_ADMIN || ($pun_user['g_moderator'] == '1' && $pun_user['g_mod_ban_users'] == '1')): ?>					<li<?php if ($page == 'admin') echo ' class="isactive"'; ?>><a href="profile.php?section=admin&amp;id=<?php echo $id ?>"><?php echo $lang_profile['Section admin'] ?></a></li>
<?php endif; ?>				</ul>
			</div>
		</div>
	</div>
<?php

}


//
// Outputs markup to display a user's avatar
//
function generate_avatar_markup($user_id)
{
	global $pun_config;

	$filetypes = array('jpg', 'gif', 'png');
	$avatar_markup = '';

	foreach ($filetypes as $cur_type)
	{
		$path = $pun_config['o_avatars_dir'].'/'.$user_id.'.'.$cur_type;

		if (file_exists(PUN_ROOT.$path) && $img_size = getimagesize(PUN_ROOT.$path))
		{
			$avatar_markup = '<img src="'.pun_htmlspecialchars(get_base_url(true).'/'.$path.'?m='.filemtime(PUN_ROOT.$path)).'" '.$img_size[3].' alt="" />';
			break;
		}
	}

	return $avatar_markup;
}


//
// Generate browser's title
//
function generate_page_title($page_title, $p = null)
{
	global $pun_config, $lang_common;

	$page_title = array_reverse($page_title);

	if ($p != null)
		$page_title[0] .= ' ('.sprintf($lang_common['Page'], forum_number_format($p)).')';

	$crumbs = implode($lang_common['Title separator'], $page_title);

	return $crumbs;
}


//
// Save array of tracked topics in cookie
//
function set_tracked_topics($tracked_topics)
{
	global $cookie_name, $cookie_path, $cookie_domain, $cookie_secure, $pun_config;

	$cookie_data = '';
	if (!empty($tracked_topics))
	{
		// Sort the arrays (latest read first)
		arsort($tracked_topics['topics'], SORT_NUMERIC);
		arsort($tracked_topics['forums'], SORT_NUMERIC);

		// Homebrew serialization (to avoid having to run unserialize() on cookie data)
		foreach ($tracked_topics['topics'] as $id => $timestamp)
			$cookie_data .= 't'.$id.'='.$timestamp.';';
		foreach ($tracked_topics['forums'] as $id => $timestamp)
			$cookie_data .= 'f'.$id.'='.$timestamp.';';

		// Enforce a byte size limit (4096 minus some space for the cookie name - defaults to 4048)
		if (strlen($cookie_data) > FORUM_MAX_COOKIE_SIZE)
		{
			$cookie_data = substr($cookie_data, 0, FORUM_MAX_COOKIE_SIZE);
			$cookie_data = substr($cookie_data, 0, strrpos($cookie_data, ';')).';';
		}
	}

	forum_setcookie($cookie_name.'_track', $cookie_data, time() + $pun_config['o_timeout_visit']);
	$_COOKIE[$cookie_name.'_track'] = $cookie_data; // Set it directly in $_COOKIE as well
}


//
// Extract array of tracked topics from cookie
//
function get_tracked_topics()
{
	global $cookie_name;

	$cookie_data = isset($_COOKIE[$cookie_name.'_track']) ? $_COOKIE[$cookie_name.'_track'] : false;
	if (!$cookie_data)
		return array('topics' => array(), 'forums' => array());

	if (strlen($cookie_data) > 4048)
		return array('topics' => array(), 'forums' => array());

	// Unserialize data from cookie
	$tracked_topics = array('topics' => array(), 'forums' => array());
	$temp = explode(';', $cookie_data);
	foreach ($temp as $t)
	{
		$type = substr($t, 0, 1) == 'f' ? 'forums' : 'topics';
		$id = intval(substr($t, 1));
		$timestamp = intval(substr($t, strpos($t, '=') + 1));
		if ($id > 0 && $timestamp > 0)
			$tracked_topics[$type][$id] = $timestamp;
	}

	return $tracked_topics;
}


//
// Update posts, topics, last_post, last_post_id and last_poster for a forum
//
function update_forum($forum_id)
{
	global $db;

	$result = $db->query('SELECT COUNT(id), SUM(num_replies) FROM '.$db->prefix.'topics WHERE forum_id='.$forum_id) or error('Unable to fetch forum topic count', __FILE__, __LINE__, $db->error());
	list($num_topics, $num_posts) = $db->fetch_row($result);

	$num_posts = $num_posts + $num_topics; // $num_posts is only the sum of all replies (we have to add the topic posts)

	$result = $db->query('SELECT last_post, last_post_id, last_poster FROM '.$db->prefix.'topics WHERE forum_id='.$forum_id.' AND moved_to IS NULL ORDER BY last_post DESC LIMIT 1') or error('Unable to fetch last_post/last_post_id/last_poster', __FILE__, __LINE__, $db->error());
	if ($db->num_rows($result)) // There are topics in the forum
	{
		list($last_post, $last_post_id, $last_poster) = $db->fetch_row($result);

		$db->query('UPDATE '.$db->prefix.'forums SET num_topics='.$num_topics.', num_posts='.$num_posts.', last_post='.$last_post.', last_post_id='.$last_post_id.', last_poster=\''.$db->escape($last_poster).'\' WHERE id='.$forum_id) or error('Unable to update last_post/last_post_id/last_poster', __FILE__, __LINE__, $db->error());
	}
	else // There are no topics
		$db->query('UPDATE '.$db->prefix.'forums SET num_topics='.$num_topics.', num_posts='.$num_posts.', last_post=NULL, last_post_id=NULL, last_poster=NULL WHERE id='.$forum_id) or error('Unable to update last_post/last_post_id/last_poster', __FILE__, __LINE__, $db->error());
}


//
// Deletes any avatars owned by the specified user ID
//
function delete_avatar($user_id)
{
	global $pun_config;

	$filetypes = array('jpg', 'gif', 'png');

	// Delete user avatar
	foreach ($filetypes as $cur_type)
	{
		if (file_exists(PUN_ROOT.$pun_config['o_avatars_dir'].'/'.$user_id.'.'.$cur_type))
			@unlink(PUN_ROOT.$pun_config['o_avatars_dir'].'/'.$user_id.'.'.$cur_type);
	}
}


//
// Delete a topic and all of it's posts
//
function delete_topic($topic_id)
{
	global $db;

	// Delete the topic and any redirect topics
	$db->query('DELETE FROM '.$db->prefix.'topics WHERE id='.$topic_id.' OR moved_to='.$topic_id) or error('Unable to delete topic', __FILE__, __LINE__, $db->error());

	// Create a list of the post IDs in this topic
	$post_ids = '';
	$result = $db->query('SELECT id FROM '.$db->prefix.'posts WHERE topic_id='.$topic_id) or error('Unable to fetch posts', __FILE__, __LINE__, $db->error());
	while ($row = $db->fetch_row($result))
		$post_ids .= ($post_ids != '') ? ','.$row[0] : $row[0];

	// Make sure we have a list of post IDs
	if ($post_ids != '')
	{
		strip_search_index($post_ids);

		// Delete posts in topic
		$db->query('DELETE FROM '.$db->prefix.'posts WHERE topic_id='.$topic_id) or error('Unable to delete posts', __FILE__, __LINE__, $db->error());
	}

	// Delete any subscriptions for this topic
	$db->query('DELETE FROM '.$db->prefix.'topic_subscriptions WHERE topic_id='.$topic_id) or error('Unable to delete subscriptions', __FILE__, __LINE__, $db->error());
	
	global $pun_user;
	require PUN_ROOT.'include/poll.php';
	poll_delete($topic_id);
}


//
// Delete a single post
//
function delete_post($post_id, $topic_id)
{
	global $db;

	$result = $db->query('SELECT id, poster, posted FROM '.$db->prefix.'posts WHERE topic_id='.$topic_id.' ORDER BY id DESC LIMIT 2') or error('Unable to fetch post info', __FILE__, __LINE__, $db->error());
	list($last_id, ,) = $db->fetch_row($result);
	list($second_last_id, $second_poster, $second_posted) = $db->fetch_row($result);

	// Delete the post
	$db->query('DELETE FROM '.$db->prefix.'posts WHERE id='.$post_id) or error('Unable to delete post', __FILE__, __LINE__, $db->error());

	strip_search_index($post_id);

	// Count number of replies in the topic
	$result = $db->query('SELECT COUNT(id) FROM '.$db->prefix.'posts WHERE topic_id='.$topic_id) or error('Unable to fetch post count for topic', __FILE__, __LINE__, $db->error());
	$num_replies = $db->result($result, 0) - 1;

	// If the message we deleted is the most recent in the topic (at the end of the topic)
	if ($last_id == $post_id)
	{
		// If there is a $second_last_id there is more than 1 reply to the topic
		if (!empty($second_last_id))
			$db->query('UPDATE '.$db->prefix.'topics SET last_post='.$second_posted.', last_post_id='.$second_last_id.', last_poster=\''.$db->escape($second_poster).'\', num_replies='.$num_replies.' WHERE id='.$topic_id) or error('Unable to update topic', __FILE__, __LINE__, $db->error());
		else
			// We deleted the only reply, so now last_post/last_post_id/last_poster is posted/id/poster from the topic itself
			$db->query('UPDATE '.$db->prefix.'topics SET last_post=posted, last_post_id=id, last_poster=poster, num_replies='.$num_replies.' WHERE id='.$topic_id) or error('Unable to update topic', __FILE__, __LINE__, $db->error());
	}
	else
		// Otherwise we just decrement the reply counter
		$db->query('UPDATE '.$db->prefix.'topics SET num_replies='.$num_replies.' WHERE id='.$topic_id) or error('Unable to update topic', __FILE__, __LINE__, $db->error());
}


//
// Delete every .php file in the forum's cache directory
//
function forum_clear_cache()
{
	$d = dir(FORUM_CACHE_DIR);
	while (($entry = $d->read()) !== false)
	{
		if (substr($entry, -4) == '.php')
			@unlink(FORUM_CACHE_DIR.$entry);
	}
	$d->close();
}


//
// Replace censored words in $text
//
function censor_words($text)
{
	global $db;
	static $search_for, $replace_with;

	// If not already built in a previous call, build an array of censor words and their replacement text
	if (!isset($search_for))
	{
		if (file_exists(FORUM_CACHE_DIR.'cache_censoring.php'))
			include FORUM_CACHE_DIR.'cache_censoring.php';
			
		
		if (!defined('PUN_CENSOR_LOADED'))
		{
			if (!defined('FORUM_CACHE_FUNCTIONS_LOADED'))
				require PUN_ROOT.'include/cache.php';
				
			generate_censoring_cache();
			require FORUM_CACHE_DIR.'cache_censoring.php';
		}
	}

	if (!empty($search_for))
		$text = substr(ucp_preg_replace($search_for, $replace_with, ' '.$text.' '), 1, -1);

	return $text;
}


//
// Determines the correct title for $user
// $user must contain the elements 'username', 'title', 'posts', 'g_id' and 'g_user_title'
//
function get_title($user)
{
	global $db, $pun_config, $pun_bans, $lang_common;
	static $ban_list, $pun_ranks;

	// If not already built in a previous call, build an array of lowercase banned usernames
	if (empty($ban_list))
	{
		$ban_list = array();

		foreach ($pun_bans as $cur_ban)
			$ban_list[] = strtolower($cur_ban['username']);
	}

	// If not already loaded in a previous call, load the cached ranks
	if ($pun_config['o_ranks'] == '1' && !defined('PUN_RANKS_LOADED'))
	{
		if (file_exists(FORUM_CACHE_DIR.'cache_ranks.php'))
			include FORUM_CACHE_DIR.'cache_ranks.php';

		if (!defined('PUN_RANKS_LOADED'))
		{
			if (!defined('FORUM_CACHE_FUNCTIONS_LOADED'))
				require PUN_ROOT.'include/cache.php';

			generate_ranks_cache();
			require FORUM_CACHE_DIR.'cache_ranks.php';
		}
	}

	// If the user has a custom title
	if ($user['title'] != '')
		$user_title = pun_htmlspecialchars($user['title']);
	// If the user is banned
	else if (in_array(strtolower($user['username']), $ban_list))
		$user_title = $lang_common['Banned'];
	// If the user group has a default user title
	else if ($user['g_user_title'] != '')
		$user_title = pun_htmlspecialchars($user['g_user_title']);
	// If the user is a guest
	else if ($user['g_id'] == PUN_GUEST)
		$user_title = $lang_common['Guest'];
	else
	{
		// Are there any ranks?
		if ($pun_config['o_ranks'] == '1' && !empty($pun_ranks))
		{
			foreach ($pun_ranks as $cur_rank)
			{
				if ($user['num_posts'] >= $cur_rank['min_posts'])
					$user_title = pun_htmlspecialchars($cur_rank['rank']);
			}
		}

		// If the user didn't "reach" any rank (or if ranks are disabled), we assign the default
		if (!isset($user_title))
			$user_title = $lang_common['Member'];
	}

	return $user_title;
}


//
// Generate a string with numbered links (for multipage scripts)
//
function paginate($num_pages, $cur_page, $link)
{
	global $lang_common;

	$pages = array();
	$link_to_all = false;

	// If $cur_page == -1, we link to all pages (used in viewforum.php)
	if ($cur_page == -1)
	{
		$cur_page = 1;
		$link_to_all = true;
	}

	if ($num_pages <= 1)
		$pages = array('<strong class="item1">1</strong>');
	else
	{
		// Add a previous page link
		if ($num_pages > 1 && $cur_page > 1)
			$pages[] = '<a'.(empty($pages) ? ' class="item1"' : '').' href="'.$link.'&amp;p='.($cur_page - 1).'">'.$lang_common['Previous'].'</a>';

		if ($cur_page > 3)
		{
			$pages[] = '<a'.(empty($pages) ? ' class="item1"' : '').' href="'.$link.'&amp;p=1">1</a>';

			if ($cur_page > 5)
				$pages[] = '<span class="spacer">'.$lang_common['Spacer'].'</span>';
		}

		// Don't ask me how the following works. It just does, OK? :-)
		for ($current = ($cur_page == 5) ? $cur_page - 3 : $cur_page - 2, $stop = ($cur_page + 4 == $num_pages) ? $cur_page + 4 : $cur_page + 3; $current < $stop; ++$current)
		{
			if ($current < 1 || $current > $num_pages)
				continue;
			else if ($current != $cur_page || $link_to_all)
				$pages[] = '<a'.(empty($pages) ? ' class="item1"' : '').' href="'.$link.'&amp;p='.$current.'">'.forum_number_format($current).'</a>';
			else
				$pages[] = '<strong'.(empty($pages) ? ' class="item1"' : '').'>'.forum_number_format($current).'</strong>';
		}

		if ($cur_page <= ($num_pages-3))
		{
			if ($cur_page != ($num_pages-3) && $cur_page != ($num_pages-4))
				$pages[] = '<span class="spacer">'.$lang_common['Spacer'].'</span>';

			$pages[] = '<a'.(empty($pages) ? ' class="item1"' : '').' href="'.$link.'&amp;p='.$num_pages.'">'.forum_number_format($num_pages).'</a>';
		}

		// Add a next page link
		if ($num_pages > 1 && !$link_to_all && $cur_page < $num_pages)
			$pages[] = '<a'.(empty($pages) ? ' class="item1"' : '').' href="'.$link.'&amp;p='.($cur_page +1).'">'.$lang_common['Next'].'</a>';
	}

	return implode(' ', $pages);
}


//
// Display a message
//
function message($message, $no_back_link = false)
{
	global $db, $lang_common, $pun_config, $pun_start, $tpl_main, $pun_user;
	
	if (defined('EVEBB_AUTO_DEBUG')) {
		$xml = '<?xml version="1.0" encoding="UTF-8"?>'."\n";
		$xml .= '<msg>'."\n";
		$xml .= '<text><![CDATA['.$message.']]></text>'."\n";
		$xml .= '</msg>'."\n";
		echo $xml;
		exit;
	} //End if.

	if (!defined('PUN_HEADER'))
	{

		$page_title = array(pun_htmlspecialchars($pun_config['o_board_title']), $lang_common['Info']);
		define('PUN_ACTIVE_PAGE', 'index');
		require PUN_ROOT.'header.php';
	}

?>

<div id="msg" class="block">
	<h2><span><?php echo $lang_common['Info'] ?></span></h2>
	<div class="box">
		<div class="inbox">
			<p><?php echo $message ?></p>
<?php if (!$no_back_link): ?>			<p><a href="javascript: history.go(-1)"><?php echo $lang_common['Go back'] ?></a></p>
<?php endif; ?>		</div>
	</div>
</div>
<?php

	require PUN_ROOT.'footer.php';
}


//
// Format a time string according to $time_format and time zones
//
function format_time($timestamp, $date_only = false, $date_format = null, $time_format = null, $time_only = false, $no_text = false)
{
	global $pun_config, $lang_common, $pun_user, $forum_date_formats, $forum_time_formats;

	if ($timestamp == '')
		return $lang_common['Never'];

	$diff = ($pun_user['timezone'] + $pun_user['dst']) * 3600;
	$timestamp += $diff;
	$now = time();

	if($date_format == null)
		$date_format = $forum_date_formats[$pun_user['date_format']];

	if($time_format == null)
		$time_format = $forum_time_formats[$pun_user['time_format']];

	$date = gmdate($date_format, $timestamp);
	$today = gmdate($date_format, $now+$diff);
	$yesterday = gmdate($date_format, $now+$diff-86400);

	if(!$no_text)
	{
		if ($date == $today)
			$date = $lang_common['Today'];
		else if ($date == $yesterday)
			$date = $lang_common['Yesterday'];
	}

	if ($date_only)
		return $date;
	else if ($time_only)
		return gmdate($time_format, $timestamp);
	else
		return $date.' '.gmdate($time_format, $timestamp);
}


//
// A wrapper for PHP's number_format function
//
function forum_number_format($number, $decimals = 0)
{
	global $lang_common;

	return is_numeric($number) ? number_format($number, $decimals, $lang_common['lang_decimal_point'], $lang_common['lang_thousands_sep']) : $number;
}


//
// Generate a random key of length $len
//
function random_key($len, $readable = false, $hash = false)
{
	$key = '';

	if ($hash)
		$key = substr(pun_hash(uniqid(rand(), true)), 0, $len);
	else if ($readable)
	{
		$chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';

		for ($i = 0; $i < $len; ++$i)
			$key .= substr($chars, (mt_rand() % strlen($chars)), 1);
	}
	else
	{
		for ($i = 0; $i < $len; ++$i)
			$key .= chr(mt_rand(33, 126));
	}

	return $key;
}


//
// Make sure that HTTP_REFERER matches base_url/script
//
function confirm_referrer($script, $error_msg = false)
{
	global $pun_config, $lang_common;
	
	// There is no referrer
	if (empty($_SERVER['HTTP_REFERER']))
		message($error_msg ? $error_msg : $lang_common['Bad referrer']);
		
	$referrer = parse_url(strtolower($_SERVER['HTTP_REFERER']));
	// Remove www subdomain if it exists
	if (strpos($referrer['host'], 'www.') === 0)
		$referrer['host'] = substr($referrer['host'], 4);
		
	$valid = parse_url(strtolower(get_base_url().'/'.$script));
	// Remove www subdomain if it exists
	if (strpos($valid['host'], 'www.') === 0)
		$valid['host'] = substr($valid['host'], 4);
		
	// Check the host and path match. Ignore the scheme, port, etc.
	if ($referrer['host'] != $valid['host'] || $referrer['path'] != $valid['path'])
		message($error_msg ? $error_msg : $lang_common['Bad referrer']);
}


//
// Generate a random password of length $len
// Compatibility wrapper for random_key
//
function random_pass($len)
{
	return random_key($len, true);
}


//
// Compute a hash of $str
//
function pun_hash($str)
{
	return sha1($str);
}


//
// Try to determine the correct remote IP-address
//
function get_remote_address()
{
    $remote_addr = $_SERVER['REMOTE_ADDR'];
    // If we are behind a reverse proxy try to find the real users IP
    if (defined('FORUM_BEHIND_REVERSE_PROXY'))
    {
        if (isset($_SERVER['HTTP_X_FORWARDED_FOR']))
        {
            // The general format of the field is:
            // X-Forwarded-For: client1, proxy1, proxy2
            // where the value is a comma+space separated list of IP addresses, the left-most being the farthest downstream client,
            // and each successive proxy that passed the request adding the IP address where it received the request from.
            $remote_addr = explode(',', $_SERVER['HTTP_X_FORWARDED_FOR']);
            $remote_addr = trim($remote_addr[0]);
        }
    }
    return $remote_addr;
}


//
// Calls htmlspecialchars with a few options already set
//
function pun_htmlspecialchars($str)
{
	return htmlspecialchars($str, ENT_QUOTES, 'UTF-8');
}


//
// Calls htmlspecialchars_decode with a few options already set
//
function pun_htmlspecialchars_decode($str)
{
	if (function_exists('htmlspecialchars_decode'))
		return htmlspecialchars_decode($str, ENT_QUOTES);

	static $translations;
	if (!isset($translations))
	{
		$translations = get_html_translation_table(HTML_SPECIALCHARS, ENT_QUOTES);
		$translations['&#039;'] = '\''; // get_html_translation_table doesn't include &#039; which is what htmlspecialchars translates ' to, but apparently that is okay?! http://bugs.php.net/bug.php?id=25927
		$translations = array_flip($translations);
	}

	return strtr($str, $translations);
}


//
// A wrapper for utf8_strlen for compatibility
//
function pun_strlen($str)
{
	return utf8_strlen($str);
}


//
// Convert \r\n and \r to \n
//
function pun_linebreaks($str)
{
	return str_replace("\r", "\n", str_replace("\r\n", "\n", $str));
}


//
// A wrapper for utf8_trim for compatibility
//
function pun_trim($str, $charlist = false)
{
	return utf8_trim($str, $charlist);
}

//
// Checks if a string is in all uppercase
//
function is_all_uppercase($string)
{
	return utf8_strtoupper($string) == $string && utf8_strtolower($string) != $string;
}


//
// Inserts $element into $input at $offset
// $offset can be either a numerical offset to insert at (eg: 0 inserts at the beginning of the array)
// or a string, which is the key that the new element should be inserted before
// $key is optional: it's used when inserting a new key/value pair into an associative array
//
function array_insert(&$input, $offset, $element, $key = null)
{
	if ($key == null)
		$key = $offset;

	// Determine the proper offset if we're using a string
	if (!is_int($offset))
		$offset = array_search($offset, array_keys($input), true);

	// Out of bounds checks
	if ($offset > count($input))
		$offset = count($input);
	else if ($offset < 0)
		$offset = 0;

	$input = array_merge(array_slice($input, 0, $offset), array($key => $element), array_slice($input, $offset));
}

//
// Display a message when board is in maintenance mode
//
function maintenance_message()
{
	global $db, $pun_config, $lang_common, $pun_user;
	
    // Send no-cache headers
    header('Expires: Thu, 21 Jul 1977 07:30:00 GMT'); // When yours truly first set eyes on this world! :)
    header('Last-Modified: '.gmdate('D, d M Y H:i:s').' GMT');
    header('Cache-Control: post-check=0, pre-check=0', false);
    header('Pragma: no-cache'); // For HTTP/1.0 compatibility
    // Send the Content-type header in case the web server is setup to send something else
    header('Content-type: text/html; charset=utf-8');

	// Deal with newlines, tabs and multiple spaces
	$pattern = array("\t", '  ', '  ');
	$replace = array('&#160; &#160; ', '&#160; ', ' &#160;');
	$message = str_replace($pattern, $replace, $pun_config['o_maintenance_message']);


	if (file_exists(PUN_ROOT.'style/'.$pun_user['style'].'/maintenance.tpl'))
	{
		$tpl_file = PUN_ROOT.'style/'.$pun_user['style'].'/maintenance.tpl';
		$tpl_inc_dir = PUN_ROOT.'style/'.$pun_user['style'].'/';
	}
	else
	{
		$tpl_file = PUN_ROOT.'include/template/maintenance.tpl';
		$tpl_inc_dir = PUN_ROOT.'include/user/';
	}

	$tpl_maint = file_get_contents($tpl_file);

	// START SUBST - <pun_include "*">
	preg_match_all('#<pun_include "([^/\\\\]*?)\.(php[45]?|inc|html?|txt)">#', $tpl_maint, $pun_includes, PREG_SET_ORDER);

	foreach ($pun_includes as $cur_include)
	{
		ob_start();

		// Allow for overriding user includes, too.
		if (file_exists($tpl_inc_dir.$cur_include[1].'.'.$cur_include[2]))
			require $tpl_inc_dir.$cur_include[1].'.'.$cur_include[2];
		else if (file_exists(PUN_ROOT.'include/user/'.$cur_include[1].'.'.$cur_include[2]))
			require PUN_ROOT.'include/user/'.$cur_include[1].'.'.$cur_include[2];
		else
			error(sprintf($lang_common['Pun include error'], htmlspecialchars($cur_include[0]), basename($tpl_file)));

		$tpl_temp = ob_get_contents();
		$tpl_maint = str_replace($cur_include[0], $tpl_temp, $tpl_maint);
		ob_end_clean();
	}
	// END SUBST - <pun_include "*">


	// START SUBST - <pun_language>
	$tpl_maint = str_replace('<pun_language>', $lang_common['lang_identifier'], $tpl_maint);
	// END SUBST - <pun_language>


	// START SUBST - <pun_content_direction>
	$tpl_maint = str_replace('<pun_content_direction>', $lang_common['lang_direction'], $tpl_maint);
	// END SUBST - <pun_content_direction>


	// START SUBST - <pun_head>
	ob_start();

	$page_title = array(pun_htmlspecialchars($pun_config['o_board_title']), $lang_common['Maintenance']);

?>
<title><?php echo generate_page_title($page_title) ?></title>
<link rel="stylesheet" type="text/css" href="style/<?php echo $pun_user['style'].'.css' ?>" />
<?php

	$tpl_temp = trim(ob_get_contents());
	$tpl_maint = str_replace('<pun_head>', $tpl_temp, $tpl_maint);
	ob_end_clean();
	// END SUBST - <pun_head>


	// START SUBST - <pun_maint_main…