* PHPMailer RFC821 SMTP email transport class.

 * Version 5.2.7

 * PHP version 5.0.0

 * @category  PHP

 * @package   PHPMailer

 * @link      https://github.com/PHPMailer/PHPMailer/

 * @author Marcus Bointon (coolbru) <phpmailer@synchromedia.co.uk>

 * @author Jim Jagielski (jimjag) <jimjag@gmail.com>

 * @author Andy Prevost (codeworxtech) <codeworxtech@users.sourceforge.net>

 * @copyright 2013 Marcus Bointon

 * @license   http://www.gnu.org/copyleft/lesser.html Distributed under the Lesser General Public License (LGPL)

 * PHPMailer RFC821 SMTP email transport class.

 *

 * Implements RFC 821 SMTP commands

 * and provides some utility methods for sending mail to an SMTP server.

 *

 * PHP Version 5.0.0

 * @category PHP

 * @package  PHPMailer

 * @link     https://github.com/PHPMailer/PHPMailer/blob/master/class.smtp.php

 * @author   Chris Ryan <unknown@example.com>

 * @author   Marcus Bointon <phpmailer@synchromedia.co.uk>

 * @license  http://www.gnu.org/copyleft/lesser.html Distributed under the Lesser General Public License (LGPL)

class SMTP

{

    /**

     * The PHPMailer SMTP Version number.

     */

    const VERSION = '5.2.7';

    /**

     * SMTP line break constant.

     */

    const CRLF = "\r\n";

    /**

     * The SMTP port to use if one is not specified.

     */

    const DEFAULT_SMTP_PORT = 25;

    /**

     * The PHPMailer SMTP Version number.

     * @type string

     * @deprecated This should be a constant

     * @see SMTP::VERSION

     */

    public $Version = '5.2.7';

    /**

     * SMTP server port number.

     * @type int

     * @deprecated This is only ever ued as default value, so should be a constant

     * @see SMTP::DEFAULT_SMTP_PORT

     */

    public $SMTP_PORT = 25;

    /**

     * SMTP reply line ending

     * @type string

     * @deprecated Use the class constant instead

     * @see SMTP::CRLF

     */

    public $CRLF = "\r\n";

    /**

     * Debug output level.

     * Options: 0 for no output, 1 for commands, 2 for data and commands

     * @type int

     */

    public $do_debug = 0;

    /**

     * The function/method to use for debugging output.

     * Options: 'echo', 'html' or 'error_log'

     * @type string

     */

    public $Debugoutput = 'echo';

    /**

     * Whether to use VERP.

     * @type bool

     */

    public $do_verp = false;

    /**

     * The SMTP timeout value for reads, in seconds.

     * @type int

     */

    public $Timeout = 15;

    /**

     * The SMTP timelimit value for reads, in seconds.

     * @type int

     */

    public $Timelimit = 30;

    /**

     * The socket for the server connection.

     * @type resource

     */

    protected $smtp_conn;

    /**

     * Error message, if any, for the last call.

     * @type string

     */

    protected $error = '';

    /**

     * The reply the server sent to us for HELO.

     * @type string

     */

    protected $helo_rply = '';

    /**

     * The most recent reply received from the server.

     * @type string

     */

    protected $last_reply = '';

    /**

     * Constructor.

     * @access public

     */

    public function __construct()

    {

        $this->smtp_conn = 0;

        $this->error = null;

        $this->helo_rply = null;

        $this->do_debug = 0;

    /**

     * Output debugging info via a user-selected method.

     * @param string $str Debug string to output

     * @return void

     */

    protected function edebug($str)

    {

        switch ($this->Debugoutput) {

            case 'error_log':

                //Don't output, just log

                error_log($str);

                break;

            case 'html':

                //Cleans up output a bit for a better looking, HTML-safe output

                echo htmlentities(

                    preg_replace('/[\r\n]+/', '', $str),

                    ENT_QUOTES,

                    'UTF-8'

                )

                . "<br>\n";

                break;

            case 'echo':

            default:

                //Just echoes whatever was received

                echo $str;

        }

    /**

     * Connect to an SMTP server.

     * @param string $host    SMTP server IP or host name

     * @param int $port    The port number to connect to

     * @param int $timeout How long to wait for the connection to open

     * @param array $options An array of options for stream_context_create()

     * @access public

     * @return bool

     */

    public function connect($host, $port = null, $timeout = 30, $options = array())

    {

        // Clear errors to avoid confusion

        $this->error = null;

        // Make sure we are __not__ connected

        if ($this->connected()) {

            // Already connected, generate error

            $this->error = array('error' => 'Already connected to a server');

        if (empty($port)) {

            $port = self::DEFAULT_SMTP_PORT;

        // Connect to the SMTP server

        $errno = 0;

        $errstr = '';

        $socket_context = stream_context_create($options);

        //Suppress errors; connection failures are handled at a higher level

        $this->smtp_conn = @stream_socket_client(

            $host . ":" . $port,

            $errno,

            $errstr,

            $timeout,

            STREAM_CLIENT_CONNECT,

            $socket_context

        );

        // Verify we connected properly

        if (empty($this->smtp_conn)) {

            $this->error = array(

                'error' => 'Failed to connect to server',

                'errno' => $errno,

                'errstr' => $errstr

            );

            if ($this->do_debug >= 1) {

                $this->edebug(

                    'SMTP -> ERROR: ' . $this->error['error']

                    . ": $errstr ($errno)"

                );

        // SMTP server can take longer to respond, give longer timeout for first read

        // Windows does not have support for this timeout function

        if (substr(PHP_OS, 0, 3) != 'WIN') {

            $max = ini_get('max_execution_time');

            if ($max != 0 && $timeout > $max) { // Don't bother if unlimited

                @set_time_limit($timeout);

            }

            stream_set_timeout($this->smtp_conn, $timeout, 0);

        // Get any announcement

        $announce = $this->get_lines();

        if ($this->do_debug >= 2) {

            $this->edebug('SMTP -> FROM SERVER:' . $announce);

        }

        return true;

    /**

     * Initiate a TLS (encrypted) session.

     * @access public

     * @return bool

     */

    public function startTLS()

    {

        if (!$this->sendCommand("STARTTLS", "STARTTLS", 220)) {

            return false;

        }

        // Begin encrypted connection

        if (!stream_socket_enable_crypto(

            $this->smtp_conn,

            true,

            STREAM_CRYPTO_METHOD_TLS_CLIENT

        )

        ) {

            return false;

        }

        return true;

    /**

     * Perform SMTP authentication.

     * Must be run after hello().

     * @see hello()

     * @param string $username    The user name

     * @param string $password    The password

     * @param string $authtype    The auth type (PLAIN, LOGIN, NTLM, CRAM-MD5)

     * @param string $realm       The auth realm for NTLM

     * @param string $workstation The auth workstation for NTLM

     * @access public

     * @return bool True if successfully authenticated.

     */

    public function authenticate(

        $username,

        $password,

        $authtype = 'LOGIN',

        $realm = '',

        $workstation = ''

    ) {

        if (empty($authtype)) {

            $authtype = 'LOGIN';

        }

        switch ($authtype) {

            case 'PLAIN':

                // Start authentication

                if (!$this->sendCommand('AUTH', 'AUTH PLAIN', 334)) {

                    return false;

                }

                // Send encoded username and password

                if (!$this->sendCommand(

                    'User & Password',

                    base64_encode("\0" . $username . "\0" . $password),

                    235

                )

                ) {

                    return false;

                }

                break;

            case 'LOGIN':

                // Start authentication

                if (!$this->sendCommand('AUTH', 'AUTH LOGIN', 334)) {

                    return false;

                }

                if (!$this->sendCommand("Username", base64_encode($username), 334)) {

                    return false;

                }

                if (!$this->sendCommand("Password", base64_encode($password), 235)) {

                    return false;

                }

                break;

            case 'NTLM':

                /*

                 * ntlm_sasl_client.php

                 * Bundled with Permission

                 *

                 * How to telnet in windows:

                 * http://technet.microsoft.com/en-us/library/aa995718%28EXCHG.65%29.aspx

                 * PROTOCOL Docs http://curl.haxx.se/rfc/ntlm.html#ntlmSmtpAuthentication

                 */

                require_once 'extras/ntlm_sasl_client.php';

                $temp = new stdClass();

                $ntlm_client = new ntlm_sasl_client_class;

                //Check that functions are available

                if (!$ntlm_client->Initialize($temp)) {

                    $this->error = array('error' => $temp->error);

                    if ($this->do_debug >= 1) {

                        $this->edebug(

                            'You need to enable some modules in your php.ini file: '

                            . $this->error['error']

                        );

                    }

                    return false;

                }

                //msg1

                $msg1 = $ntlm_client->TypeMsg1($realm, $workstation); //msg1

                if (!$this->sendCommand(

                    'AUTH NTLM',

                    'AUTH NTLM ' . base64_encode($msg1),

                    334

                )

                ) {

                    return false;

                }

                //Though 0 based, there is a white space after the 3 digit number

                //msg2

                $challenge = substr($this->last_reply, 3);

                $challenge = base64_decode($challenge);

                $ntlm_res = $ntlm_client->NTLMResponse(

                    substr($challenge, 24, 8),

                    $password

                );

                //msg3

                $msg3 = $ntlm_client->TypeMsg3(

                    $ntlm_res,

                    $username,

                    $realm,

                    $workstation

                );

                // send encoded username

                return $this->sendCommand('Username', base64_encode($msg3), 235);

                break;

            case 'CRAM-MD5':

                // Start authentication

                if (!$this->sendCommand('AUTH CRAM-MD5', 'AUTH CRAM-MD5', 334)) {

                    return false;

                }

                // Get the challenge

                $challenge = base64_decode(substr($this->last_reply, 4));

                // Build the response

                $response = $username . ' ' . $this->hmac($challenge, $password);

                // send encoded credentials

                return $this->sendCommand('Username', base64_encode($response), 235);

                break;

        }

        return true;

    /**

     * Calculate an MD5 HMAC hash.

     * Works like hash_hmac('md5', $data, $key)

     * in case that function is not available

     * @param string $data The data to hash

     * @param string $key  The key to hash with

     * @access protected

     * @return string

     */

    protected function hmac($data, $key)

    {

        if (function_exists('hash_hmac')) {

            return hash_hmac('md5', $data, $key);

        // The following borrowed from

        // http://php.net/manual/en/function.mhash.php#27225

        // RFC 2104 HMAC implementation for php.

        // Creates an md5 HMAC.

        // Eliminates the need to install mhash to compute a HMAC

        // by Lance Rushing

        $b = 64; // byte length for md5

        if (strlen($key) > $b) {

            $key = pack('H*', md5($key));

        $key = str_pad($key, $b, chr(0x00));

        $ipad = str_pad('', $b, chr(0x36));

        $opad = str_pad('', $b, chr(0x5c));

        $k_ipad = $key ^ $ipad;

        $k_opad = $key ^ $opad;

        return md5($k_opad . pack('H*', md5($k_ipad . $data)));