Live email validation

Here's something I just threw together real quick because I had a need for it. But others might find it useful:

<?
$split = preg_split('/^(.*)<(.*)>(.*)/', $_REQUEST['email'], -1, PREG_SPLIT_DELIM_CAPTURE|PREG_SPLIT_NO_EMPTY);
$email = array_pop ($split);
$split = explode ("@", $email);
$domain = $split[1];

getmxrr ($domain, $a, $b);
if ($a) {
foreach ($a as $key => $val) {
$c[$b[$key]] = $val;
}
ksort ($c);
} else {
$c[0] = $domain;
}

$fp = fsockopen (array_shift($c), 25, $errno, $errstr, 30);
$return = fgets ($fp, 1024);
fputs ($fp, "helo none.com\r\n");
$return = fgets ($fp, 1024);
fputs ($fp, "mail from:<postmaster@none.com>\r\n");
$return = fgets ($fp, 1024);
fputs ($fp, "rcpt to:<" . $email . ">\r\n");
$return = fgets ($fp, 1024);
fputs ($fp, "quit");

fclose($fp);

if (substr($return, 0, 3) > 250) {
echo "Bad email";
} else {
echo "Good email";
}
?>

PHP:

If you pass an email address as an email variable to the script, it will look up the domain's SMTP server, contact it, and see if the email address is legit or not.

You should change the none.com domain to your domain and probably will want to use something more useful (like a true/false variable) instead of echoing out Good Email/Bad Email.

Some mail servers will not tell you if an address is good or not with the RCPT TO command, so for those mail servers, it wouldn't work all that well, since it would always accept emails for any address.

 

Well, it has nothing to do with SPF. Also, the script is not intended to be on a public web server (especially not as a stand alone script). In my case, it's used from the shell only.

 

I would guess that VERY few domains use SPF. digitalpoint.com has no SPF record, and it works fine for me. Either way, if someone cared about SPF, they could use it. Still wouldn't affect the script itself if someone chooses to use SPF in their server setup or not.