如何使用gethostbyaddr阻止主机ip（$ _ SERVER ['REMOTE_ADDR']）; [重复]

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I'm getting spammed pretty hard and trying to stop it… I have a code similar to this to grab IPs and then block them but also trying to add this code to block anyone visiting my site with a host that starts with the string 'tor'. What comes after that varies greatly, so only want to match the first three letters and then block…

<?php

// The function to get the visitor's IP Host info.
function getUserHostIP(){
    //check ip host from share internet
    $blackListHost=gethostbyaddr($_SERVER['REMOTE_ADDR']);
    if (strpos($blackListHost, 'tor') === 0) {
        header("Location: unauthorized.php");
        die();
     }
}

//The user
getUserHostIP();

?>

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