Mass Convert IP Addresses to Domain Names with a Filter

A PHP script to convert many IP addresses to domain names. You can paste text with addresses and it’ll convert them.


if ($_POST['text']) {
        $t = $_POST['text'];
        $o = preg_replace('/(\d+\.\d+\.\d+\.\d+)/e', 'get_host('\1')', $t);
        # $o = preg_replace('/(\d+\.\d+\.\d+\.\d+)/e', 'gethostbyaddr('\1')', $t);
        echo '<pre>'.$o.'</pre>';

function get_host($ip){
        $ptr= implode(".",array_reverse(explode(".",$ip)))."";
        $host = dns_get_record($ptr,DNS_PTR);
        if ($host == null) return $ip;
        else return $host[0]['target'];

<p>This script takes text with embedded IP addresses as input, and converts the addresses
to domain names.</p>
<form method="post">
<textarea name="text" rows="10" cols="80">
<br />
<input type="submit" />