The following function performs pop3 authentication. Returns NULL on error, or true/false to indicate username/password matching:
$address is the hostname of the server and $ssl is a boolean that indicates whether an SSL connection is requested.
<?php
function pop3authCheck($username, $password, $address, $ssl)
{
if ($ssl)
$uri="ssl://$address:995";
else
$uri="tcp://$address:110";
$fp=fsockopen($uri);
if (!$fp)
return(NULL);
$st=fgets($fp, 512);
if (substr($st, 0, 3)!="+OK")
{
fclose($fp);
return(NULL);
}
$st="USER $username\n";
if (fwrite($fp, $st)!=strlen($st))
{
fclose($fp);
return(NULL);
}
$st=fgets($fp, 512);
if (substr($st, 0, 3)!="+OK")
{
fclose($fp);
return(NULL);
}
$st="PASS $password\n";
if (fwrite($fp, $st)!=strlen($st))
{
fclose($fp);
return(NULL);
}
$st=fgets($fp, 512);
fclose($fp);
if (substr($st, 0, 3)=="+OK")
return(true);
else if (substr($st, 0, 4)=="+ERR")
return(false);
else
return(NULL);
}
?>