View file wordpress/wp-includes/class-smtp.php

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<?php
////////////////////////////////////////////////////
// SMTP - PHP SMTP class
//
// Version 1.02
//
// Define an SMTP class that can be used to connect
// and communicate with any SMTP server. It implements
// all the SMTP functions defined in RFC821 except TURN.
//
// Author: Chris Ryan
//
// License: LGPL, see LICENSE
////////////////////////////////////////////////////

/**
 * SMTP is rfc 821 compliant and implements all the rfc 821 SMTP
 * commands except TURN which will always return a not implemented
 * error. SMTP also provides some utility methods for sending mail
 * to an SMTP server.
 * @package PHPMailer
 * @author Chris Ryan
 */
class SMTP
{
    /**
     *  SMTP server port
     *  @var int
     */
    var $SMTP_PORT = 25;
    
    /**
     *  SMTP reply line ending
     *  @var string
     */
    var $CRLF = "\r\n";
    
    /**
     *  Sets whether debugging is turned on
     *  @var bool
     */
    var $do_debug;       # the level of debug to perform

    /**#@+
     * @access private
     */
    var $smtp_conn;      # the socket to the server
    var $error;          # error if any on the last call
    var $helo_rply;      # the reply the server sent to us for HELO
    /**#@-*/

    /**
     * Initialize the class so that the data is in a known state.
     * @access public
     * @return void
     */
    function SMTP() {
        $this->smtp_conn = 0;
        $this->error = null;
        $this->helo_rply = null;

        $this->do_debug = 0;
    }

    /*************************************************************
     *                    CONNECTION FUNCTIONS                  *
     ***********************************************************/

    /**
     * Connect to the server specified on the port specified.
     * If the port is not specified use the default SMTP_PORT.
     * If tval is specified then a connection will try and be
     * established with the server for that number of seconds.
     * If tval is not specified the default is 30 seconds to
     * try on the connection.
     *
     * SMTP CODE SUCCESS: 220
     * SMTP CODE FAILURE: 421
     * @access public
     * @return bool
     */
    function Connect($host,$port=0,$tval=30) {
        # set the error val to null so there is no confusion
        $this->error = null;

        # make sure we are __not__ connected
        if($this->connected()) {
            # ok we are connected! what should we do?
            # for now we will just give an error saying we
            # are already connected
            $this->error =
                array("error" => "Already connected to a server");
            return false;
        }

        if(empty($port)) {
            $port = $this->SMTP_PORT;
        }

        #connect to the smtp server
        $this->smtp_conn = fsockopen($host,    # the host of the server
                                     $port,    # the port to use
                                     $errno,   # error number if any
                                     $errstr,  # error message if any
                                     $tval);   # give up after ? secs
        # verify we connected properly
        if(empty($this->smtp_conn)) {
            $this->error = array("error" => "Failed to connect to server",
                                 "errno" => $errno,
                                 "errstr" => $errstr);
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": $errstr ($errno)" . $this->CRLF;
            }
            return false;
        }

        # sometimes the SMTP server takes a little longer to respond
        # so we will give it a longer timeout for the first read
        // Windows still does not have support for this timeout function
        if(substr(PHP_OS, 0, 3) != "WIN")
           socket_set_timeout($this->smtp_conn, $tval, 0);

        # get any announcement stuff
        $announce = $this->get_lines();

        # set the timeout  of any socket functions at 1/10 of a second
        //if(function_exists("socket_set_timeout"))
        //   socket_set_timeout($this->smtp_conn, 0, 100000);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $announce;
        }

        return true;
    }

    /**
     * Performs SMTP authentication.  Must be run after running the
     * Hello() method.  Returns true if successfully authenticated.
     * @access public
     * @return bool
     */
    function Authenticate($username, $password) {
        // Start authentication
        fputs($this->smtp_conn,"AUTH LOGIN" . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($code != 334) {
            $this->error =
                array("error" => "AUTH not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        // Send encoded username
        fputs($this->smtp_conn, base64_encode($username) . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($code != 334) {
            $this->error =
                array("error" => "Username not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        // Send encoded password
        fputs($this->smtp_conn, base64_encode($password) . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($code != 235) {
            $this->error =
                array("error" => "Password not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        return true;
    }

    /**
     * Returns true if connected to a server otherwise false
     * @access private
     * @return bool
     */
    function Connected() {
        if(!empty($this->smtp_conn)) {
            $sock_status = socket_get_status($this->smtp_conn);
            if($sock_status["eof"]) {
                # hmm this is an odd situation... the socket is
                # valid but we aren't connected anymore
                if($this->do_debug >= 1) {
                    echo "SMTP -> NOTICE:" . $this->CRLF .
                         "EOF caught while checking if connected";
                }
                $this->Close();
                return false;
            }
            return true; # everything looks good
        }
        return false;
    }

    /**
     * Closes the socket and cleans up the state of the class.
     * It is not considered good to use this function without
     * first trying to use QUIT.
     * @access public
     * @return void
     */
    function Close() {
        $this->error = null; # so there is no confusion
        $this->helo_rply = null;
        if(!empty($this->smtp_conn)) {
            # close the connection and cleanup
            fclose($this->smtp_conn);
            $this->smtp_conn = 0;
        }
    }


    /***************************************************************
     *                        SMTP COMMANDS                       *
     *************************************************************/

    /**
     * Issues a data command and sends the msg_data to the server
     * finializing the mail transaction. $msg_data is the message
     * that is to be send with the headers. Each header needs to be
     * on a single line followed by a <CRLF> with the message headers
     * and the message body being seperated by and additional <CRLF>.
     *
     * Implements rfc 821: DATA <CRLF>
     *
     * SMTP CODE INTERMEDIATE: 354
     *     [data]
     *     <CRLF>.<CRLF>
     *     SMTP CODE SUCCESS: 250
     *     SMTP CODE FAILURE: 552,554,451,452
     * SMTP CODE FAILURE: 451,554
     * SMTP CODE ERROR  : 500,501,503,421
     * @access public
     * @return bool
     */
    function Data($msg_data) {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Data() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"DATA" . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 354) {
            $this->error =
                array("error" => "DATA command not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        # the server is ready to accept data!
        # according to rfc 821 we should not send more than 1000
        # including the CRLF
        # characters on a single line so we will break the data up
        # into lines by \r and/or \n then if needed we will break
        # each of those into smaller lines to fit within the limit.
        # in addition we will be looking for lines that start with
        # a period '.' and append and additional period '.' to that
        # line. NOTE: this does not count towards are limit.

        # normalize the line breaks so we know the explode works
        $msg_data = str_replace("\r\n","\n",$msg_data);
        $msg_data = str_replace("\r","\n",$msg_data);
        $lines = explode("\n",$msg_data);

        # we need to find a good way to determine is headers are
        # in the msg_data or if it is a straight msg body
        # currently I'm assuming rfc 822 definitions of msg headers
        # and if the first field of the first line (':' sperated)
        # does not contain a space then it _should_ be a header
        # and we can process all lines before a blank "" line as
        # headers.
        $field = substr($lines[0],0,strpos($lines[0],":"));
        $in_headers = false;
        if(!empty($field) && !strstr($field," ")) {
            $in_headers = true;
        }

        $max_line_length = 998; # used below; set here for ease in change

        while(list(,$line) = @each($lines)) {
            $lines_out = null;
            if($line == "" && $in_headers) {
                $in_headers = false;
            }
            # ok we need to break this line up into several
            # smaller lines
            while(strlen($line) > $max_line_length) {
                $pos = strrpos(substr($line,0,$max_line_length)," ");

                # Patch to fix DOS attack
                if(!$pos) {
                    $pos = $max_line_length - 1;
                }

                $lines_out[] = substr($line,0,$pos);
                $line = substr($line,$pos + 1);
                # if we are processing headers we need to
                # add a LWSP-char to the front of the new line
                # rfc 822 on long msg headers
                if($in_headers) {
                    $line = "\t" . $line;
                }
            }
            $lines_out[] = $line;

            # now send the lines to the server
            while(list(,$line_out) = @each($lines_out)) {
                if(strlen($line_out) > 0)
                {
                    if(substr($line_out, 0, 1) == ".") {
                        $line_out = "." . $line_out;
                    }
                }
                fputs($this->smtp_conn,$line_out . $this->CRLF);
            }
        }

        # ok all the message data has been sent so lets get this
        # over with aleady
        fputs($this->smtp_conn, $this->CRLF . "." . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => "DATA not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }
        return true;
    }

    /**
     * Expand takes the name and asks the server to list all the
     * people who are members of the _list_. Expand will return
     * back and array of the result or false if an error occurs.
     * Each value in the array returned has the format of:
     *     [ <full-name> <sp> ] <path>
     * The definition of <path> is defined in rfc 821
     *
     * Implements rfc 821: EXPN <SP> <string> <CRLF>
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE FAILURE: 550
     * SMTP CODE ERROR  : 500,501,502,504,421
     * @access public
     * @return string array
     */
    function Expand($name) {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Expand() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"EXPN " . $name . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => "EXPN not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        # parse the reply and place in our array to return to user
        $entries = explode($this->CRLF,$rply);
        while(list(,$l) = @each($entries)) {
            $list[] = substr($l,4);
        }

        return $list;
    }

    /**
     * Sends the HELO command to the smtp server.
     * This makes sure that we and the server are in
     * the same known state.
     *
     * Implements from rfc 821: HELO <SP> <domain> <CRLF>
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE ERROR  : 500, 501, 504, 421
     * @access public
     * @return bool
     */
    function Hello($host="") {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Hello() without being connected");
            return false;
        }

        # if a hostname for the HELO wasn't specified determine
        # a suitable one to send
        if(empty($host)) {
            # we need to determine some sort of appopiate default
            # to send to the server
            $host = "localhost";
        }

        // Send extended hello first (RFC 2821)
        if(!$this->SendHello("EHLO", $host))
        {
            if(!$this->SendHello("HELO", $host))
                return false;
        }

        return true;
    }

    /**
     * Sends a HELO/EHLO command.
     * @access private
     * @return bool
     */
    function SendHello($hello, $host) {
        fputs($this->smtp_conn, $hello . " " . $host . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER: " . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => $hello . " not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        $this->helo_rply = $rply;
        
        return true;
    }

    /**
     * Gets help information on the keyword specified. If the keyword
     * is not specified then returns generic help, ussually contianing
     * A list of keywords that help is available on. This function
     * returns the results back to the user. It is up to the user to
     * handle the returned data. If an error occurs then false is
     * returned with $this->error set appropiately.
     *
     * Implements rfc 821: HELP [ <SP> <string> ] <CRLF>
     *
     * SMTP CODE SUCCESS: 211,214
     * SMTP CODE ERROR  : 500,501,502,504,421
     * @access public
     * @return string
     */
    function Help($keyword="") {
        $this->error = null; # to avoid confusion

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Help() without being connected");
            return false;
        }

        $extra = "";
        if(!empty($keyword)) {
            $extra = " " . $keyword;
        }

        fputs($this->smtp_conn,"HELP" . $extra . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 211 && $code != 214) {
            $this->error =
                array("error" => "HELP not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        return $rply;
    }

    /**
     * Starts a mail transaction from the email address specified in
     * $from. Returns true if successful or false otherwise. If True
     * the mail transaction is started and then one or more Recipient
     * commands may be called followed by a Data command.
     *
     * Implements rfc 821: MAIL <SP> FROM:<reverse-path> <CRLF>
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE SUCCESS: 552,451,452
     * SMTP CODE SUCCESS: 500,501,421
     * @access public
     * @return bool
     */
    function Mail($from) {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Mail() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"MAIL FROM:<" . $from . ">" . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => "MAIL not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }
        return true;
    }

    /**
     * Sends the command NOOP to the SMTP server.
     *
     * Implements from rfc 821: NOOP <CRLF>
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE ERROR  : 500, 421
     * @access public
     * @return bool
     */
    function Noop() {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Noop() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"NOOP" . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => "NOOP not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }
        return true;
    }

    /**
     * Sends the quit command to the server and then closes the socket
     * if there is no error or the $close_on_error argument is true.
     *
     * Implements from rfc 821: QUIT <CRLF>
     *
     * SMTP CODE SUCCESS: 221
     * SMTP CODE ERROR  : 500
     * @access public
     * @return bool
     */
    function Quit($close_on_error=true) {
        $this->error = null; # so there is no confusion

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Quit() without being connected");
            return false;
        }

        # send the quit command to the server
        fputs($this->smtp_conn,"quit" . $this->CRLF);

        # get any good-bye messages
        $byemsg = $this->get_lines();

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $byemsg;
        }

        $rval = true;
        $e = null;

        $code = substr($byemsg,0,3);
        if($code != 221) {
            # use e as a tmp var cause Close will overwrite $this->error
            $e = array("error" => "SMTP server rejected quit command",
                       "smtp_code" => $code,
                       "smtp_rply" => substr($byemsg,4));
            $rval = false;
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $e["error"] . ": " .
                         $byemsg . $this->CRLF;
            }
        }

        if(empty($e) || $close_on_error) {
            $this->Close();
        }

        return $rval;
    }

    /**
     * Sends the command RCPT to the SMTP server with the TO: argument of $to.
     * Returns true if the recipient was accepted false if it was rejected.
     *
     * Implements from rfc 821: RCPT <SP> TO:<forward-path> <CRLF>
     *
     * SMTP CODE SUCCESS: 250,251
     * SMTP CODE FAILURE: 550,551,552,553,450,451,452
     * SMTP CODE ERROR  : 500,501,503,421
     * @access public
     * @return bool
     */
    function Recipient($to) {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Recipient() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"RCPT TO:<" . $to . ">" . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250 && $code != 251) {
            $this->error =
                array("error" => "RCPT not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }
        return true;
    }

    /**
     * Sends the RSET command to abort and transaction that is
     * currently in progress. Returns true if successful false
     * otherwise.
     *
     * Implements rfc 821: RSET <CRLF>
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE ERROR  : 500,501,504,421
     * @access public
     * @return bool
     */
    function Reset() {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Reset() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"RSET" . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => "RSET failed",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        return true;
    }

    /**
     * Starts a mail transaction from the email address specified in
     * $from. Returns true if successful or false otherwise. If True
     * the mail transaction is started and then one or more Recipient
     * commands may be called followed by a Data command. This command
     * will send the message to the users terminal if they are logged
     * in.
     *
     * Implements rfc 821: SEND <SP> FROM:<reverse-path> <CRLF>
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE SUCCESS: 552,451,452
     * SMTP CODE SUCCESS: 500,501,502,421
     * @access public
     * @return bool
     */
    function Send($from) {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Send() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"SEND FROM:" . $from . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => "SEND not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }
        return true;
    }

    /**
     * Starts a mail transaction from the email address specified in
     * $from. Returns true if successful or false otherwise. If True
     * the mail transaction is started and then one or more Recipient
     * commands may be called followed by a Data command. This command
     * will send the message to the users terminal if they are logged
     * in and send them an email.
     *
     * Implements rfc 821: SAML <SP> FROM:<reverse-path> <CRLF>
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE SUCCESS: 552,451,452
     * SMTP CODE SUCCESS: 500,501,502,421
     * @access public
     * @return bool
     */
    function SendAndMail($from) {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                "error" => "Called SendAndMail() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"SAML FROM:" . $from . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => "SAML not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }
        return true;
    }

    /**
     * Starts a mail transaction from the email address specified in
     * $from. Returns true if successful or false otherwise. If True
     * the mail transaction is started and then one or more Recipient
     * commands may be called followed by a Data command. This command
     * will send the message to the users terminal if they are logged
     * in or mail it to them if they are not.
     *
     * Implements rfc 821: SOML <SP> FROM:<reverse-path> <CRLF>
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE SUCCESS: 552,451,452
     * SMTP CODE SUCCESS: 500,501,502,421
     * @access public
     * @return bool
     */
    function SendOrMail($from) {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                "error" => "Called SendOrMail() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"SOML FROM:" . $from . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => "SOML not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }
        return true;
    }

    /**
     * This is an optional command for SMTP that this class does not
     * support. This method is here to make the RFC821 Definition
     * complete for this class and __may__ be implimented in the future
     *
     * Implements from rfc 821: TURN <CRLF>
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE FAILURE: 502
     * SMTP CODE ERROR  : 500, 503
     * @access public
     * @return bool
     */
    function Turn() {
        $this->error = array("error" => "This method, TURN, of the SMTP ".
                                        "is not implemented");
        if($this->do_debug >= 1) {
            echo "SMTP -> NOTICE: " . $this->error["error"] . $this->CRLF;
        }
        return false;
    }

    /**
     * Verifies that the name is recognized by the server.
     * Returns false if the name could not be verified otherwise
     * the response from the server is returned.
     *
     * Implements rfc 821: VRFY <SP> <string> <CRLF>
     *
     * SMTP CODE SUCCESS: 250,251
     * SMTP CODE FAILURE: 550,551,553
     * SMTP CODE ERROR  : 500,501,502,421
     * @access public
     * @return int
     */
    function Verify($name) {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Verify() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"VRFY " . $name . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250 && $code != 251) {
            $this->error =
                array("error" => "VRFY failed on name '$name'",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }
        return $rply;
    }

    /*******************************************************************
     *                       INTERNAL FUNCTIONS                       *
     ******************************************************************/

    /**
     * Read in as many lines as possible
     * either before eof or socket timeout occurs on the operation.
     * With SMTP we can tell if we have more lines to read if the
     * 4th character is '-' symbol. If it is a space then we don't
     * need to read anything else.
     * @access private
     * @return string
     */
    function get_lines() {
        $data = "";
        while($str = fgets($this->smtp_conn,515)) {
            if($this->do_debug >= 4) {
                echo "SMTP -> get_lines(): \$data was \"$data\"" .
                         $this->CRLF;
                echo "SMTP -> get_lines(): \$str is \"$str\"" .
                         $this->CRLF;
            }
            $data .= $str;
            if($this->do_debug >= 4) {
                echo "SMTP -> get_lines(): \$data is \"$data\"" . $this->CRLF;
            }
            # if the 4th character is a space then we are done reading
            # so just break the loop
            if(substr($str,3,1) == " ") { break; }
        }
        return $data;
    }

}


 ?>