php项目的index.php文件，项目是原生php写的

Question

<?php

require( dirname(__FILE__) . '/config.php' );

global $GLOBAL_SYSTEM;


if(isset($_GET['userId']) && $_GET['userId'] != ""){
    $user_name = $_GET['userId'];
    $param = '<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:lev="http://session.level1.services.sdk.actionsoft.com/">
   <soapenv:Header><aws-auth xmlns="http://services.sdk.actionsoft.com/">fecaca56a326610b24626b163814a02c</aws-auth>
<soapenv:Header/>
   <soapenv:Body>
      <lev:checkSession>
         <userId>'.$_GET['userId'].'</userId>   <sid>'.$_GET['sid'].'</sid>
      </lev:checkSession>
   </soapenv:Body>
</soapenv:Envelope>';

    
    $sessionServer = "http://mzwa-123.6655.la:8090/services/SessionService";
    if(defined('SSO_SESSION_SERVER')){
        $sessionServer = SSO_SESSION_SERVER;
    }
    
    $securityServer = "http://mzwa-123.6655.la:8090/services/SecurityService";
    if(defined('SSO_SECURITY_SERVER')){
        $securityServer = SSO_SECURITY_SERVER;
    }
    
    $xmls = fetch($sessionServer, $param);
    
    if($xmls === false){
        sd_redirect($GLOBAL_SYSTEM[PRODUCT_TYPE]["index"]);
    }
    
    $xml_values = "";
    
    $parser = xml_parser_create('UTF-8');
    xml_parse_into_struct($parser, trim($xmls), $xml_values);
    xml_parser_free($parser);

    
    foreach ($xml_values as $value){
        if($value['tag'] == "RETURN"){
            if($value['value'] == 'false'){
                sd_redirect($GLOBAL_SYSTEM[PRODUCT_TYPE]["index"]);
            }elseif($value['value'] == 'true'){
                $user = &sd_get_user($user_name);
                if (!empty($user) ) {
                    $result = login_without_pwd_verify($user);
                    $_SESSION["user"] = $user_name;
                    if ($_SESSION["role"] == UserDao::$ROLE_CLOUD_USER) {
                        if (I2System::isI2Cloud()){
                            sd_redirect("cloud/home.php");
                        }else{
                            sd_redirect($GLOBAL_SYSTEM[PRODUCT_TYPE]["index"]);
                        }
                    } else {
                        sd_redirect("i2/home.php");
                    }
                }
            }
            break;
        }
    }
}else{
    sd_redirect($GLOBAL_SYSTEM[PRODUCT_TYPE]["index"]."?".$_SERVER["QUERY_STRING"]);
}