Adam C Taylor

<?php
session_start();
$ntlmserver = "smtpserver.local";

function left($string, $count){
        return substr($string, 0, $count);
}

$headers = apache_request_headers();

if (!isset($headers['Authorization'])){
    header('HTTP/1.1 401 Unauthorized');
    header('WWW-Authenticate: NTLM');
    exit;
}

$auth = $headers['Authorization'];


if (substr($auth,0,5) == 'NTLM ') {
    $msg = base64_decode(substr($auth, 5));
    if (substr($msg, 0, 8) != "NTLMSSP\x00")
        die('error header not recognised');

    if ($msg[8] == "\x01") {
                $holder = apache_request_headers();
                $_SESSION['TYPE1MSG'] = $holder['Authorization'];


    if(!$_SESSION['AUTH']){
            $smtp_server = pfsockopen($ntlmserver, 25, $errno, $errstr, 30);
            if(!$smtp_server)
                    {
                            exit;
                    }
            fwrite($smtp_server, "EHLO\r\n");

            $stop=0;

            while (!$stop)
                {
                    $data = fgets($smtp_server, 512);

                    if(left($data,6)=="250 OK")
                        {
                        fwrite($smtp_server, "AUTH $_SESSION[TYPE1MSG]\r\n");
                        }
                    else if(left($data,3)=="334")
                        {
                        $_SESSION['TYPE2MSG']=substr($data,4);
                        $stop=1;
                        }

                }

            $_SESSION['AUTH']=1;
        }

        $msg2 = $_SESSION['TYPE2MSG'];
        header('HTTP/1.1 401 Unauthorized');
        header('WWW-Authenticate: NTLM '.trim($msg2));
        exit;
    }
    else if ($msg[8] == "\x03") {
        $holder = apache_request_headers();
                $_SESSION['TYPE3MSG'] = substr($holder['Authorization'],5);

            if(!$_SESSION['AUTH2']){
                    $smtp_server = pfsockopen($ntlmserver, 25, $errno, $errstr, 30);
                    if(!$smtp_server)
                            {
                                    exit;
                            }

                    $stop=0;

                    fwrite($smtp_server, "$_SESSION[TYPE3MSG]\r\n");

                    while (!$stop)
                        {
                            $data = fgets($smtp_server, 512);
                            //print_r($data);

                            if(left($data,3)=="235")
                                {
                                $_SESSION['AUTH']="235";
                                $stop=1;
                                }
                            else if(left($data,3)=="535")
                                {
                                $_SESSION['AUTH']="535";
                                $stop=1;
                                exit;
                                }

                        }

                    fwrite($smtp_server, "QUIT\r\n");
                    fclose($smtp_server);
                    $_SESSION['AUTH2']=1;
        }

        function get_msg_str($msg, $start, $unicode = true) {
            $len = (ord($msg[$start+1]) * 256) + ord($msg[$start]);
            $off = (ord($msg[$start+5]) * 256) + ord($msg[$start+4]);
            if ($unicode)
                return str_replace("\0", '', substr($msg, $off, $len));
            else
                return substr($msg, $off, $len);
        }
        $_SESSION['USER'] = get_msg_str($msg, 36);
        $_SESSION['DOMAIN'] = get_msg_str($msg, 28);
        $_SESSION['WORKSTATION'] = get_msg_str($msg, 44);

        //print_r($auth);
    }


}

print_r($_SESSION);
?>