<?php #    class.POP3.php3

/*

    class.POP3.php3 v1.0    99/03/24 CDI cdi@thewebmasters.net
    Copyright (c) 1999 - CDI (cdi@thewebmasters.net) All Rights Reserved

    An RFC 1939 compliant wrapper class for the POP3 protocol.
*/

class POP3
{
    var $ERROR        = "";        //    Error string.

    var $TIMEOUT    = 60;        //    Default timeout before giving up on a
                                //    network operation.

    var $COUNT        = -1;        //    Mailbox msg count

    var $BUFFER        = 512;        //    Socket buffer for socket fgets() calls.
                                //    Per RFC 1939 the returned line a POP3
                                //    server can send is 512 bytes.

    var $FP            = "";        //    The connection to the server's
                                //    file descriptor

    var $MAILSERVER    = "";        // Set this to hard code the server name

    var $DEBUG        = false;    // set to true to echo pop3
                                // commands and responses to error_log
                                // this WILL log passwords!

    var $BANNER        = "";        //    Holds the banner returned by the
                                //    pop server - used for apop()

    var $RFC1939    = true;        //    Set by noop(). See rfc1939.txt    
                                //

    var $ALLOWAPOP    = false;    //    Allow or disallow apop()
                                //    This must be set to true
                                //    manually.

    function POP3 ( $server = "", $timeout = "" )
    {
        settype($this->BUFFER,"integer");
        if(!empty($server))
        {
            // Do not allow programs to alter MAILSERVER
            // if it is already specified. They can get around
            // this if they -really- want to, so don't count on it.
            if(empty($this->MAILSERVER))
            {
                $this->MAILSERVER = $server;
            }
        }
        if(!empty($timeout))
        {
            settype($timeout,"integer");
            $this->TIMEOUT = $timeout;
            set_time_limit($timeout);
        }
        return true;
    }

    function update_timer ()
    {
        set_time_limit($this->TIMEOUT);
        return true;
    }

    function connect ($server, $port = 110)
    {
        //    Opens a socket to the specified server. Unless overridden,
        //    port defaults to 110. Returns true on success, false on fail

        // If MAILSERVER is set, override $server with it's value

        if(!empty($this->MAILSERVER))
        {
            $server = $this->MAILSERVER;
        }

        if(empty($server))
        {
            $this->ERROR = "POP3 connect: No server specified";  
            unset($this->FP);
            return false;
        }

        $fp = fsockopen("$server", $port, &$errno, &$errstr);

        if(!$fp)
        {
            $this->ERROR = "POP3 connect: Error [$errno] [$errstr]";
            unset($this->FP);
            return false;
        }

        set_socket_blocking($fp,-1);
        $this->update_timer();
        $reply = fgets($fp,$this->BUFFER);
        $reply = $this->strip_clf($reply);
        if($this->DEBUG) { error_log("POP3 SEND [connect: $server] GOT [$reply]",0); }
        if(!$this->is_ok($reply))
        {
            $this->ERROR = "POP3 connect: Error [$reply]";
            unset($this->FP);
            return false;
        }
        $this->FP = $fp;
        $this->BANNER = $this->parse_banner($reply);
        $this->RFC1939 = $this->noop();
        if(!$this->RFC1939)
        {
            $this->ERROR = "POP3: premature NOOP OK, NOT an RFC 1939 Compliant server";
            $this->quit();
            return false;
        }
        return true;
    }

    function noop ()
    {
        if(!isset($this->FP))
        {
            $this->ERROR = "POP3 noop: No connection to server";
            return false;
        }
        $cmd = "NOOP";
        $reply = $this->send_cmd($cmd);
        if(!$this->is_ok($reply))
        {
            return false;
        }
        return true;
    }

    function user ($user = "")
    {
        // Sends the USER command, returns true or false

        if(empty($user))
        {
            $this->ERROR = "POP3 user: no user id submitted";
            return false;
        }
        if(!isset($this->FP))
        {
            $this->ERROR = "POP3 user: connection not established";
            return false;
        }
        $reply = $this->send_cmd("USER $user");
        if(!$this->is_ok($reply))
        {
            $this->ERROR = "POP3 user: Error [$reply]";
            return false;
        }
        return true;
    }

    function pass ($pass = "")
    {
        // Sends the PASS command, returns # of msgs in mailbox,
        // returns false (undef) on Auth failure

        if(empty($pass))
        {
            $this->ERROR = "POP3 pass: no password submitted";
            return false;
        }
        if(!isset($this->FP))
        {
            $this->ERROR = "POP3 pass: connection not established";
            return false;
        }
        $reply = $this->send_cmd("PASS $pass");
        if(!$this->is_ok($reply))
        {
            $this->ERROR = "POP3 pass: authentication failed [$reply]";
            $this->quit();
            return false;
        }
        //    Auth successful.
        $count = $this->last("count");
        $this->COUNT = $count;
        $this->RFC1939 = $this->noop();
        if(!$this->RFC1939)
        {
            $this->ERROR = "POP3 pass: NOOP failed. Server not RFC 1939 compliant";
            $this->quit();
            return false;
        }
        return $count;
    }

    function apop ($login,$pass)
    {
        //    Attempts an APOP login. If this fails, it'll
        //    try a standard login. YOUR SERVER MUST SUPPORT
        //    THE USE OF THE APOP COMMAND!
        //    (apop is optional per rfc1939)

        if(!isset($this->FP))
        {
            $this->ERROR = "POP3 apop: No connection to server";
            return false;
        }

        if(!$this->ALLOWAPOP)
        {
            $retVal = $this->login($login,$pass);
            return $retVal;
        }

        if(empty($login))
        {
            $this->ERROR = "POP3 apop: No login ID submitted";
            return false;
        }
        if(empty($pass))
        {
            $this->ERROR = "POP3 apop: No password submitted";
            return false;
        }
        $banner = $this->BANNER;
        if( (!$banner) or (empty($banner)) )
        {
            $this->ERROR = "POP3 apop: No server banner - aborted";
            $retVal = $this->login($login,$pass);
            return $retVal;
        }
        $AuthString = $banner;
        $AuthString .= $pass;
        $APOPString = md5($AuthString);
        $cmd = "APOP $login $APOPString";
        $reply = $this->send_cmd($cmd);
        if(!$this->is_ok($reply))
        {
            $this->ERROR = "POP3 apop: apop authentication failed - abort";
            $retVal = $this->login($login,$pass);
            return $retVal;
        }
        //    Auth successful.
        $count = $this->last("count");
        $this->COUNT = $count;
        $this->RFC1939 = $this->noop();
        if(!$this->RFC1939)
        {
            $this->ERROR = "POP3 apop: NOOP failed. Server not RFC 1939 compliant";
            $this->quit();
            return false;
        }
        return $count;
    }

    function login ($login = "", $pass = "")
    {
        // Sends both user and pass. Returns # of msgs in mailbox or
        // false on failure (or -1, if the error occurs while getting
        // the number of messages.)

        if(!isset($this->FP))
        {
            $this->ERROR = "POP3 login: No connection to server";
            return false;
        }
        $fp = $this->FP;
        if(!$this->user($login))
        {
            //    Preserve the error generated by user()
            return false;
        }
        $count = $this->pass($pass);
        if( (!$count) or ($count == -1) )
        {
            //    Preserve the error generated by last() and pass()
            return false;
        }
        return $count;
    }

    function top ($msgNum, $numLines = "0")
    {
        //    Gets the header and first $numLines of the msg body
        //    returns data in an array with each returned line being
        //    an array element. If $numLines is empty, returns
        //    only the header information, and none of the body.

        if(!isset($this->FP))
        {
            $this->ERROR = "POP3 top: No connection to server";
            return false;
        }
        $this->update_timer();

        $fp = $this->FP;
        $buffer = $this->BUFFER;
        $cmd = "TOP $msgNum $numLines";
        fwrite($fp, "TOP $msgNum $numLines\r\n");
        $reply = fgets($fp, $buffer);
        $reply = $this->strip_clf($reply);
        if($this->DEBUG) { @error_log("POP3 SEND [$cmd] GOT [$reply]",0); }
        if(!$this->is_ok($reply))
        {
            $this->ERROR = "POP3 top: Error [$reply]";
            return false;
        }

        $count = 0;
        $MsgArray = array();

        $line = fgets($fp,$buffer);
        while ( !ereg("^\.\r\n",$line))
        {
            $MsgArray[$count] = $line;
            $count++;
            $line = fgets($fp,$buffer);
            if(empty($line))    { break; }
        }

        return $MsgArray;
    }

    function pop_list ($msgNum = "")
    {
        //    If called with an argument, returns that msgs' size in octets
        //    No argument returns an associative array of undeleted
        //    msg numbers and their sizes in octets

        if(!isset($this->FP))
        {
            $this->ERROR = "POP3 pop_list: No connection to server";
            return false;
        }
        $fp = $this->FP;
        $Total = $this->COUNT;
        if( (!$Total) or ($Total == -1) )
        {
            return false;
        }
        if($Total == 0)
        {
            return array("0","0");
            // return -1;    // mailbox empty
        }

        $this->update_timer();

        if(!empty($msgNum))
        {
            $cmd = "LIST $msgNum";
            fwrite($fp,"$cmd\r\n");
            $reply = fgets($fp,$this->BUFFER);
            $reply = $this->strip_clf($reply);
            if($this->DEBUG) { @error_log("POP3 SEND [$cmd] GOT [$reply]",0); }
            if(!$this->is_ok($reply))
            {
                $this->ERROR = "POP3 pop_list: Error [$reply]";
                return false;
            }
            list($junk,$num,$size) = explode(" ",$reply);
            return $size;
        }
        $cmd = "LIST";
        $reply = $this->send_cmd($cmd);
        if(!$this->is_ok($reply))
        {
            $reply = $this->strip_clf($reply);
            $this->ERROR = "POP3 pop_list: Error [$reply]";
            return false;
        }
        $MsgArray = array();
        $MsgArray[0] = $Total;
        for($msgC=1;$msgC <= $Total; $msgC++)
        {
            if($msgC > $Total) { break; }
            $line = fgets($fp,$this->BUFFER);
            $line = $this->strip_clf($line);
            if(ereg("^\.",$line))
            {
                $this->ERROR = "POP3 pop_list: Premature end of list";
                return false;
            }
            list($thisMsg,$msgSize) = explode(" ",$line);
            settype($thisMsg,"integer");
            if($thisMsg != $msgC)
            {
                $MsgArray[$msgC] = "deleted";
            }
            else
            {
                $MsgArray[$msgC] = $msgSize;
            }
        }
        return $MsgArray;
    }

    function get ($msgNum)
    {
        //    Retrieve the specified msg number. Returns an array
        //    where each line of the msg is an array element.

        if(!isset($this->FP))
        {
            $this->ERROR = "POP3 get: No connection to server";
            return false;
        }

        $this->update_timer();

        $fp = $this->FP;
        $buffer = $this->BUFFER;
        $cmd = "RETR $msgNum";
        $reply = $this->send_cmd($cmd);

        if(!$this->is_ok($reply))
        {
            $this->ERROR = "POP3 get: Error [$reply]";
            return false;
        }

        $count = 0;
        $MsgArray = array();

        $line = fgets($fp,$buffer);
        while ( !ereg("^\.\r\n",$line))
        {
            $MsgArray[$count] = $line;
            $count++;
            $line = fgets($fp,$buffer);
            if(empty($line))    { break; }
        }
        return $MsgArray;
    }

    function last ( $type = "count" )
    {
        //    Returns the highest msg number in the mailbox.
        //    returns -1 on error, 0+ on success, if type != count
        //    results in a popstat() call (2 element array returned)

        $last = -1;
        if(!isset($this->FP))
        {
            $this->ERROR = "POP3 last: No connection to server";
            return $last;
        }

        $reply = $this->send_cmd("STAT");
        if(!$this->is_ok($reply))
        {
            $this->ERROR = "POP3 last: error [$reply]";
            return $last;
        }

        $Vars = explode(" ",$reply);
        $count = $Vars[1];
        $size = $Vars[2];
        settype($count,"integer");
        settype($size,"integer");
        if($type != "count")
        {
            return array($count,$size);
        }
        return $count;
    }

    function reset ()
    {
        //    Resets the status of the remote server. This includes
        //    resetting the status of ALL msgs to not be deleted.
        //    This method automatically closes the connection to the server.

        if(!isset($this->FP))
        {
            $this->ERROR = "POP3 reset: No connection to server";
            return false;
        }
        $reply = $this->send_cmd("RSET");
        if(!$this->is_ok($reply))
        {
            //    The POP3 RSET command -never- gives a -ERR
            //    response - if it ever does, something truely
            //    wild is going on.

            $this->ERROR = "POP3 reset: Error [$reply]";
            @error_log("POP3 reset: ERROR [$reply]",0);
        }
        $this->quit();
        return true;
    }

    function send_cmd ( $cmd = "" )
    {
        //    Sends a user defined command string to the
        //    POP server and returns the results. Useful for
        //    non-compliant or custom POP servers.
        //    Do NOT include the \r\n as part of your command
        //    string - it will be appended automatically.

        //    The return value is a standard fgets() call, which
        //    will read up to $this->BUFFER bytes of data, until it
        //    encounters a new line, or EOF, whichever happens first.

        //    This method works best if $cmd responds with only
        //    one line of data.

        if(!isset($this->FP))
        {
            $this->ERROR = "POP3 send_cmd: No connection to server";
            return false;
        }

        if(empty($cmd))
        {
            $this->ERROR = "POP3 send_cmd: Empty command string";
            return "";
        }

        $fp = $this->FP;
        $buffer = $this->BUFFER;
        $this->update_timer();
        fwrite($fp,"$cmd\r\n");
        $reply = fgets($fp,$buffer);
        $reply = $this->strip_clf($reply);
        if($this->DEBUG) { @error_log("POP3 SEND [$cmd] GOT [$reply]",0); }
        return $reply;
    }

    function quit ()
    {
        //    Closes the connection to the POP3 server, deleting
        //    any msgs marked as deleted.

        if(!isset($this->FP))
        {
            $this->ERROR = "POP3 quit: connection does not exist";
            return false;
        }
        $fp = $this->FP;
        $cmd = "QUIT";
        fwrite($fp,"$cmd\r\n");
        $reply = fgets($fp,$this->BUFFER);
        $reply = $this->strip_clf($reply);
        if($this->DEBUG) { @error_log("POP3 SEND [$cmd] GOT [$reply]",0); }
        fclose($fp);
        unset($this->FP);
        return true;
    }

    function popstat ()
    {
        //    Returns an array of 2 elements. The number of undeleted
        //    msgs in the mailbox, and the size of the mbox in octets.

        $PopArray = $this->last("array");

        if($PopArray == -1) { return false; }

        if( (!$PopArray) or (empty($PopArray)) )
        {
            return false;
        }
        return $PopArray;
    }

    function uidl ($msgNum = "")
    {
        //    Returns the UIDL of the msg specified. If called with
        //    no arguments, returns an associative array where each
        //    undeleted msg num is a key, and the msg's uidl is the element
        //    Array element 0 will contain the total number of msgs

        if(!isset($this->FP))
        {
            $this->ERROR = "POP3 uidl: No connection to server";
            return false;
        }

        $fp = $this->FP;
        $buffer = $this->BUFFER;

        if(!empty($msgNum))
        {
            $cmd = "UIDL $msgNum";
            $reply = $this->send_cmd($cmd);
            if(!$this->is_ok($reply))
            {
                $this->ERROR = "POP3 uidl: Error [$reply]";
                return false;
            }
            list ($ok,$num,$myUidl) = explode(" ",$reply);
            return $myUidl;
        }
        else
        {
            $this->update_timer();

            $UIDLArray = array();
            $Total = $this->COUNT;
            $UIDLArray[0] = $Total;

            if ($Total < 1)
            {
                return $UIDLArray;
            }
            $cmd = "UIDL";
            fwrite($fp, "UIDL\r\n");
            $reply = fgets($fp, $buffer);
            $reply = $this->strip_clf($reply);
            if($this->DEBUG) { @error_log("POP3 SEND [$cmd] GOT [$reply]",0); }
            if(!$this->is_ok($reply))
            {
                $this->ERROR = "POP3 uidl: Error [$reply]";
                return false;
            }

            $line = "";
            $count = 1;
            $line = fgets($fp,$buffer);
            while ( !ereg("^\.\r\n",$line))
            {
                if(ereg("^\.\r\n",$line))
                {
                    break;
                }
                list ($msg,$msgUidl) = explode(" ",$line);
                $msgUidl = $this->strip_clf($msgUidl);
                if($count == $msg)
                {
                    $UIDLArray[$msg] = $msgUidl;
                }
                else
                {
                    $UIDLArray[$count] = "deleted";
                }
                $count++;
                $line = fgets($fp,$buffer);
            }
        }
        return $UIDLArray;
    }

    function delete ($msgNum = "")
    {
        //    Flags a specified msg as deleted. The msg will not
        //    be deleted until a quit() method is called.

        if(!isset($this->FP))
        {
            $this->ERROR = "POP3 delete: No connection to server";
            return false;
        }
        if(empty($msgNum))
        {
            $this->ERROR = "POP3 delete: No msg number submitted";
            return false;
        }
        $reply = $this->send_cmd("DELE $msgNum");
        if(!$this->is_ok($reply))
        {
            $this->ERROR = "POP3 delete: Command failed [$reply]";
            return false;
        }
        return true;
    }

    //    *********************************************************

    //    The following methods are internal to the class.

    function is_ok ($cmd = "")
    {
        //    Return true or false on +OK or -ERR

        if(empty($cmd))                    { return false; }
        if ( ereg ("^\+OK", $cmd ) )    { return true; }
        return false;
    }

    function strip_clf ($text = "")
    {
        // Strips \r\n from server responses

        if(empty($text)) { return $text; }
        $stripped = ereg_replace("\r","",$text);
        $stripped = ereg_replace("\n","",$stripped);
        return $stripped;
    }

    function parse_banner ( $server_text )
    {
        $outside = true;
        $banner = "";
        $length = strlen($server_text);
        for($count =0; $count < $length; $count++)
        {
            $digit = substr($server_text,$count,1);
            if(!empty($digit))
            {
                if( (!$outside) and ($digit != '<') and ($digit != '>') )
                {
                    $banner .= $digit;
                }
                if ($digit == '<')
                {
                    $outside = false;
                }
                if($digit == '>')
                {
                    $outside = true;
                }
            }
        }
        $banner = $this->strip_clf($banner);    // Just in case
        return "<$banner>";
    }

}    // End class

?>