[hidjra]

i wrote this code to do exactly what i stated above. I'm just not sure this is the best way for doing this. Could some one have a look at this?

PHP Code:

// copied from vb3.5 gold
function fetch_alt_ip()
    {
        if (isset($_SERVER['HTTP_CLIENT_IP']))
        {
            $alt_ip = $_SERVER['HTTP_CLIENT_IP'];
        }
        else if (isset($_SERVER['HTTP_X_FORWARDED_FOR']) AND preg_match_all('#\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}#s', $_SERVER['HTTP_X_FORWARDED_FOR'], $matches))
        {
            // make sure we dont pick up an internal IP defined by RFC1918
            foreach ($matches[0] AS $ip)
            {
                if (!preg_match("#^(10|172\.16|192\.168)\.#", $ip))
                {
                    $alt_ip = $ip;
                    break;
                }
            }
        }
        else if (isset($_SERVER['HTTP_FROM']))
        {
            $alt_ip = $_SERVER['HTTP_FROM'];
        }
        else
        {
            $alt_ip = $_SERVER['REMOTE_ADDR'];
        }

        return $alt_ip;
    }

// define vars
define('COOKIE_SALT', 'blablablabla');
$alt_ip = fetch_alt_ip();
define('ALT_IP', $alt_ip);
define('IPADDRESS', $_SERVER['REMOTE_ADDR']);


if($_COOKIE['bbsessionhash']){
  //check if cookie exists
  $sessionhash = $_COOKIE['bbsessionhash'];
}elseif($_REQUEST['s']){
  // check session in request
  $sessionhash = $_REQUEST['s'];
}else{
  // no cookie and no session, use vb engine en redirect
  chdir('/xx/xx/xxx/forums');
  require('./global.php');
  header("Location: " .str_replace('.php', '.php' .$vbulletin->session->vars['sessionurl_q']. '&', $_SERVER['PHP_SELF']));
}

define('SESSION_IDHASH', md5($_SERVER['HTTP_USER_AGENT'] . ALT_IP ));
define('SESSION_HOST', substr(IPADDRESS, 0, 15)); 
define('USER_AGENT', $_SERVER['HTTP_USER_AGENT']);

$cookietime = intval(time() - 900);
$sessie = $DB_site->query_first("SELECT * FROM session WHERE sessionhash = '$sessionhash' AND lastactivity > '$cookietime' AND host = '" .SESSION_HOST. "' AND idhash = '" .SESSION_IDHASH. "' AND useragent='" .USER_AGENT. "'");

if(($_COOKIE['bbuserid']) AND ($_COOKIE['bbpassword'])){
  $getuser = $DB_site->query("SELECT * FROM user WHERE userid = '$_COOKIE[bbuserid]'");
  $user = $DB_site->fetch_array($getuser);
  if($_COOKIE['bbpassword'] == md5($user['password'] . COOKIE_SALT)){
    $user['logouthash'] = md5($user['userid'] . $user['salt'] . COOKIE_SALT);
    $bbuserinfo = $user;
  }
}elseif($sessie['userid']){
  $getuser = $DB_site->query("SELECT * FROM user WHERE userid = '$sessie[userid]'");
  $user = $DB_site->fetch_array($getuser);
  $user['logouthash'] = md5($user['userid'] . $user['salt'] . COOKIE_SALT);
  $bbuserinfo = $user;
}

$DB_site->query("UPDATE session SET lastactivity = '" .time(). "' WHERE sessionhash = '$sessionhash'");
if($bbuserinfo['userid']>0){
  $DB_site->query("UPDATE user SET lastactivity = '" .time(). "' WHERE userid = '$bbuserinfo[userid]'");
}