<?php
   /** smtp.php
    **
    ** This contains all the functions needed to send messages through
    ** an smtp server or sendmail.
    **
    ** $Id$
    **/

   if (defined('smtp_php'))
      return;
   define('smtp_php', true);

   include('../functions/addressbook.php');

   global $username, $popuser, $domain;

   // This should most probably go to some initialization...
   if (ereg("^([^@%/]+)[@%/](.+)$", $username, $usernamedata)) {
      $popuser = $usernamedata[1];
      $domain  = $usernamedata[2];
	  unset($usernamedata);
   } else {
      $popuser = $username;
   }
   // We need domain for smtp
   if (!$domain)
      $domain = getenv('HOSTNAME');

   // Returns true only if this message is multipart
   function isMultipart () {
      global $attachments;
      
      if (count($attachments)>0)
         return true;
      else
         return false;
   }

   // looks up aliases in the addressbook and expands them to
   // the full address.
   function expandAddrs ($array) {
      $abook = addressbook_init();
      for ($i=0; $i < count($array); $i++) {
         $result = $abook->lookup($array[$i]);
         $ret = "";
         if (isset($result['email'])) {
            if (isset($result['name'])) {
               $ret = '"'.$result['name'].'" ';
            }
            $ret .= '<'.$result['email'].'>';
            $array[$i] = $ret;
         }
	 else
	 {
	    $array[$i] = '<' . $array[$i] . '>';
	 }
      }
      return $array;
   }

   // Attach the files that are due to be attached
   function attachFiles ($fp) {
      global $attachments, $attachment_dir;

      $length = 0;

      if (isMultipart()) {
         foreach ($attachments as $info)
	 {
	    if (isset($info['type']))
 	       $filetype = $info['type'];
            else
               $filetype = 'application/octet-stream';
            
            $header = '--'.mimeBoundary()."\r\n";
            $header .= "Content-Type: $filetype; name=\"" .
	        $info['remotefilename'] . "\"\r\n";
            $header .= "Content-Disposition: attachment; filename=\"" .
	        $info['remotefilename'] . "\"\r\n";
            $header .= "Content-Transfer-Encoding: base64\r\n\r\n";
            fputs ($fp, $header);
            $length += strlen($header);
            
            $file = fopen ($attachment_dir . $info['localfilename'], 'r');
            while ($tmp = fread($file, 570)) {
               $encoded = chunk_split(base64_encode($tmp));
               $length += strlen($encoded);
               fputs ($fp, $encoded);
            }
            fclose ($file);
         }
      }

      return $length;
   }

   // Delete files that are uploaded for attaching
   function deleteAttachments() {
      global $attachments, $attachment_dir;

      if (isMultipart()) {
         reset($attachments);
         while (list($localname, $remotename) = each($attachments)) {
            if (!ereg ("\\/", $localname)) {
               unlink ($attachment_dir.$localname);
               unlink ($attachment_dir.$localname.'.info');
            }
         }
      }
   }

   // Return a nice MIME-boundary
   function mimeBoundary () {
      static $mimeBoundaryString;

      if ($mimeBoundaryString == "") {
         $mimeBoundaryString = "----=_" . 
	     GenerateRandomString(60, '\'()+,-./:=?_', 7);
      }

      return $mimeBoundaryString;
   }

   /* Time offset for correct timezone */
   function timezone () {
      global $invert_time;
      
      $diff_second = date('Z');
      if ($invert_time)
          $diff_second = - $diff_second;
      if ($diff_second > 0)
         $sign = '+';
      else
         $sign = '-';

      $diff_second = abs($diff_second);

      $diff_hour = floor ($diff_second / 3600);
      $diff_minute = floor (($diff_second-3600*$diff_hour) / 60);

      $zonename = '('.strftime('%Z').')';
      $result = sprintf ("%s%02d%02d %s", $sign, $diff_hour, $diff_minute, $zonename);
      return ($result);
   }

   /* Print all the needed RFC822 headers */
   function write822Header ($fp, $t, $c, $b, $subject, $more_headers) {
      global $REMOTE_ADDR, $SERVER_NAME, $REMOTE_PORT;
      global $data_dir, $username, $popuser, $domain, $version, $useSendmail;
      global $default_charset, $HTTP_VIA, $HTTP_X_FORWARDED_FOR;
      global $REMOTE_HOST;

      // Storing the header to make sure the header is the same
      // everytime the header is printed.
      static $header, $headerlength;

      if ($header == '') {
         $to = expandAddrs(parseAddrs($t));
         $cc = expandAddrs(parseAddrs($c));
         $bcc = expandAddrs(parseAddrs($b));
         $reply_to = getPref($data_dir, $username, 'reply_to');
         $from = getPref($data_dir, $username, 'full_name');
         $from_addr = getPref($data_dir, $username, 'email_address');

         if ($from_addr == '')
            $from_addr = $popuser.'@'.$domain;
         
         $to_list = getLineOfAddrs($to);
         $cc_list = getLineOfAddrs($cc);
         $bcc_list = getLineOfAddrs($bcc);

         /* Encoding 8-bit characters and making from line */
         $subject = encodeHeader($subject);
         if ($from == '')
            $from = "<$from_addr>";
         else
            $from = '"' . encodeHeader($from) . "\" <$from_addr>";
         
         /* This creates an RFC 822 date */
         $date = date("D, j M Y H:i:s ", mktime()) . timezone();

         /* Create a message-id */
         $message_id = '<' . $REMOTE_PORT . '.' . $REMOTE_ADDR . '.';
         $message_id .= time() . '.squirrel@' . $SERVER_NAME .'>';
         
         /* Make an RFC822 Received: line */
         if (isset($REMOTE_HOST))
            $received_from = "$REMOTE_HOST ([$REMOTE_ADDR])";
         else
            $received_from = $REMOTE_ADDR;
    
         if (isset($HTTP_VIA) || isset ($HTTP_X_FORWARDED_FOR)) {
            if ($HTTP_X_FORWARDED_FOR == '')
               $HTTP_X_FORWARDED_FOR = 'unknown';
            $received_from .= " (proxying for $HTTP_X_FORWARDED_FOR)";
         }            
    
         $header  = "Received: from $received_from\r\n";
         $header .= "        (SquirrelMail authenticated user $username)\r\n";
         $header .= "        by $SERVER_NAME with HTTP;\r\n";
         $header .= "        $date\r\n";
         
         /* Insert the rest of the header fields */
         $header .= "Message-ID: $message_id\r\n";
         $header .= "Date: $date\r\n";
         $header .= "Subject: $subject\r\n";
         $header .= "From: $from\r\n";
         $header .= "To: $to_list\r\n";    // Who it's TO

	 /* Insert headers from the $more_headers array */
	 if(is_array($more_headers)) {
	    reset($more_headers);
	    while(list($h_name, $h_val) = each($more_headers)) {
	       $header .= sprintf("%s: %s\r\n", $h_name, $h_val);
	    }
	 }

         if ($cc_list) {
            $header .= "Cc: $cc_list\r\n"; // Who the CCs are
         }
         
         if ($reply_to != '')
            $header .= "Reply-To: $reply_to\r\n";
         
         if ($useSendmail) {
            if ($bcc_list) {
               // BCCs is removed from header by sendmail
               $header .= "Bcc: $bcc_list\r\n"; 
            }
         }
         
         $header .= "X-Mailer: SquirrelMail (version $version)\r\n"; // Identify SquirrelMail
         
         // Do the MIME-stuff
         $header .= "MIME-Version: 1.0\r\n";
         
         if (isMultipart()) {
            $header .= 'Content-Type: multipart/mixed; boundary="';
            $header .= mimeBoundary();
            $header .= "\"\r\n";
         } else {
            if ($default_charset != '')
               $header .= "Content-Type: text/plain; charset=$default_charset\r\n";
            else
               $header .= "Content-Type: text/plain;\r\n";
            $header .= "Content-Transfer-Encoding: 8bit\r\n";
         }
         $header .= "\r\n"; // One blank line to separate header and body

         $headerlength = strlen($header);
      }     
      
      // Write the header
      fputs ($fp, $header);

      return $headerlength;
   }

   // Send the body
   function writeBody ($fp, $passedBody) {
      global $default_charset;

      $attachmentlength = 0;
      
      if (isMultipart()) {
         $body = '--'.mimeBoundary()."\r\n";

         if ($default_charset != "")
            $body .= "Content-Type: text/plain; charset=$default_charset\r\n";
         else 
            $body .= "Content-Type: text/plain\r\n";

         $body .= "Content-Transfer-Encoding: 8bit\r\n\r\n";
         $body .= $passedBody . "\r\n\r\n";
         fputs ($fp, $body);

         $attachmentlength = attachFiles($fp);

         if (!isset($postbody)) $postbody = "";
         $postbody .= "\r\n--".mimeBoundary()."--\r\n\r\n";
         fputs ($fp, $postbody);
      } else {
         $body = $passedBody . "\r\n";
         fputs ($fp, $body);
         $postbody = "\r\n";
         fputs ($fp, $postbody);
      }

      return (strlen($body) + strlen($postbody) + $attachmentlength);
   }

   // Send mail using the sendmail command
   function sendSendmail($t, $c, $b, $subject, $body, $more_headers) {
      global $sendmail_path, $popuser, $username, $domain;

      // Build envelope sender address. Make sure it doesn't contain 
      // spaces or other "weird" chars that would allow a user to
      // exploit the shell/pipe it is used in.
      $envelopefrom = "$popuser@$domain";
      $envelopefrom = ereg_replace("[[:blank:]]",'', $envelopefrom);
      $envelopefrom = ereg_replace("[[:space:]]",'', $envelopefrom);
      $envelopefrom = ereg_replace("[[:cntrl:]]",'', $envelopefrom);

      // open pipe to sendmail
      $fp = popen (escapeshellcmd("$sendmail_path -t -f$envelopefrom"), 'w');
      
      $headerlength = write822Header ($fp, $t, $c, $b, $subject, $more_headers);
      $bodylength = writeBody($fp, $body);

      pclose($fp);

      return ($headerlength + $bodylength);
   }

   function smtpReadData($smtpConnection) {
      $read = fgets($smtpConnection, 1024);
      $counter = 0;
      while ($read) {
         echo $read . '<BR>';
         $data[$counter] = $read;
         $read = fgets($smtpConnection, 1024);
         $counter++;
      }
   }

   function sendSMTP($t, $c, $b, $subject, $body, $more_headers) {
      global $username, $popuser, $domain, $version, $smtpServerAddress, $smtpPort,
         $data_dir, $color, $use_authenticated_smtp;

      $to = expandAddrs(parseAddrs($t));
      $cc = expandAddrs(parseAddrs($c));
      $bcc = expandAddrs(parseAddrs($b));
      $from_addr = getPref($data_dir, $username, 'email_address');

      if (!$from_addr)
         $from_addr = "$popuser@$domain";

      $smtpConnection = fsockopen($smtpServerAddress, $smtpPort, $errorNumber, $errorString);
      if (!$smtpConnection) {
         echo 'Error connecting to SMTP Server.<br>';
         echo "$errorNumber : $errorString<br>";
         exit;
      }
      $tmp = fgets($smtpConnection, 1024);
      if (errorCheck($tmp, $smtpConnection)!=5) return(0);

      $to_list = getLineOfAddrs($to);
      $cc_list = getLineOfAddrs($cc);

      /** Lets introduce ourselves */
      if (! isset ($use_authenticated_smtp) || $use_authenticated_smtp == false) {
         fputs($smtpConnection, "HELO $domain\r\n");
         $tmp = fgets($smtpConnection, 1024);
      if (errorCheck($tmp, $smtpConnection)!=5) return(0);
      } else {
         fputs($smtpConnection, "EHLO $domain\r\n");
         $tmp = fgets($smtpConnection, 1024);
         if (errorCheck($tmp, $smtpConnection)!=5) return(0);

         fputs($smtpConnection, "AUTH LOGIN\r\n");
         $tmp = fgets($smtpConnection, 1024);
         if (errorCheck($tmp, $smtpConnection)!=5) return(0);

         fputs($smtpConnection, base64_encode ($username) . "\r\n");
         $tmp = fgets($smtpConnection, 1024);
         if (errorCheck($tmp, $smtpConnection)!=5) return(0);

         fputs($smtpConnection, base64_encode ($OneTimePadDecrypt($key, $onetimepad)) . "\r\n");
         $tmp = fgets($smtpConnection, 1024);
         if (errorCheck($tmp, $smtpConnection)!=5) return(0);
      }

      /** Ok, who is sending the message? */
      fputs($smtpConnection, "MAIL FROM: <$from_addr>\r\n");
      $tmp = fgets($smtpConnection, 1024);
      if (errorCheck($tmp, $smtpConnection)!=5) return(0);

      /** send who the recipients are */
      for ($i = 0; $i < count($to); $i++) {
         fputs($smtpConnection, "RCPT TO: $to[$i]\r\n");
         $tmp = fgets($smtpConnection, 1024);
         if (errorCheck($tmp, $smtpConnection)!=5) return(0);
      }
      for ($i = 0; $i < count($cc); $i++) {
         fputs($smtpConnection, "RCPT TO: $cc[$i]\r\n");
         $tmp = fgets($smtpConnection, 1024);
         if (errorCheck($tmp, $smtpConnection)!=5) return(0);
      }
      for ($i = 0; $i < count($bcc); $i++) {
         fputs($smtpConnection, "RCPT TO: $bcc[$i]\r\n");
         $tmp = fgets($smtpConnection, 1024);
         if (errorCheck($tmp, $smtpConnection)!=5) return(0);
      }

      /** Lets start sending the actual message */
      fputs($smtpConnection, "DATA\r\n");
      $tmp = fgets($smtpConnection, 1024);
      if (errorCheck($tmp, $smtpConnection)!=5) return(0);

      // Send the message
      $headerlength = write822Header ($smtpConnection, $t, $c, $b, $subject, $more_headers);
      $bodylength = writeBody($smtpConnection, $body);

      fputs($smtpConnection, ".\r\n"); // end the DATA part
      $tmp = fgets($smtpConnection, 1024);
      $num = errorCheck($tmp, $smtpConnection, verbose);
      if ($num != 250) {
         $tmp = nl2br(htmlspecialchars($tmp));
         displayPageHeader($color, 'None');
         include ("../functions/display_messages.php");
         $lines = nl2br(htmlspecialchars($lines));
         $msg  = "Message not sent!<br>\nReason given: $tmp";
         plain_error_message($msg, $color);
         return(0);
      }

      fputs($smtpConnection, "QUIT\r\n"); // log off

      fclose($smtpConnection);

      return ($headerlength + $bodylength);
   }


   function errorCheck($line, $smtpConnection) {
      global $color;
      include '../functions/page_header.php';
      
      // Read new lines on a multiline response
      $lines = $line;
      while(ereg("^[0-9]+-", $line)) {
	 $line = fgets($smtpConnection, 1024);
	 $lines .= $line;
      }

      // Status:  0 = fatal
      //          5 = ok

      $err_num = substr($line, 0, strpos($line, " "));
      switch ($err_num) {
         case 500:   $message = 'Syntax error; command not recognized';
                     $status = 0;
                     break;
         case 501:   $message = 'Syntax error in parameters or arguments';
                     $status = 0;
                     break;
         case 502:   $message = 'Command not implemented';
                     $status = 0;
                     break;
         case 503:   $message = 'Bad sequence of commands';
                     $status = 0;
                     break;
         case 504:   $message = 'Command parameter not implemented';
                     $status = 0;
                     break;


         case 211:   $message = 'System status, or system help reply';
                     $status = 5;
                     break;
         case 214:   $message = 'Help message';
                     $status = 5;
                     break;


         case 220:   $message = 'Service ready';
                     $status = 5;
                     break;
         case 221:   $message = 'Service closing transmission channel';
                     $status = 5;
                     break;
         case 421:   $message = 'Service not available, closing chanel';
                     $status = 0;
                     break;

         case 235:   return(5); break;
         case 250:   $message = 'Requested mail action okay, completed';
                     $status = 5;
                     break;
         case 251:   $message = 'User not local; will forward';
                     $status = 5;
                     break;
         case 334:   return(5); break;
         case 450:   $message = 'Requested mail action not taken:  mailbox unavailable';
                     $status = 0;
                     break;
         case 550:   $message = 'Requested action not taken:  mailbox unavailable';
                     $status = 0;
                     break;
         case 451:   $message = 'Requested action aborted:  error in processing';
                     $status = 0;
                     break;
         case 551:   $message = 'User not local; please try forwarding';
                     $status = 0;
                     break;
         case 452:   $message = 'Requested action not taken:  insufficient system storage';
                     $status = 0;
                     break;
         case 552:   $message = 'Requested mail action aborted:  exceeding storage allocation';
                     $status = 0;
                     break;
         case 553:   $message = 'Requested action not taken: mailbox name not allowed';
                     $status = 0;
                     break;
         case 354:   $message = 'Start mail input; end with .';
                     $status = 5;
                     break;
         case 554:   $message = 'Transaction failed';
                     $status = 0;
                     break;
         default:    $message = 'Unknown response: '. nl2br(htmlspecialchars($lines));
                     $status = 0;
                     $error_num = '001';
                     break;
      }

      if ($status == 0) {
         displayPageHeader($color, 'None');
		 include ("../functions/display_messages.php");
         $lines = nl2br(htmlspecialchars($lines));
		 $msg  = $message . "<br>\nServer replied: $lines";
		 plain_error_message($msg, $color);
      }
      if ($verbose == "") return $status;
      return $err_num;
   }

   function sendMessage($t, $c, $b, $subject, $body, $reply_id) {
      global $useSendmail, $msg_id, $is_reply, $mailbox, $onetimepad;
      global $data_dir, $username, $domain, $key, $version, $sent_folder, $imapServerAddress, $imapPort;
      $more_headers = Array();

      $imap_stream = sqimap_login($username, $key, $imapServerAddress, $imapPort, 1);

      if (isset($reply_id) && $reply_id) {
         sqimap_mailbox_select ($imap_stream, $mailbox);
         sqimap_messages_flag ($imap_stream, $reply_id, $reply_id, 'Answered');

         // Insert In-Reply-To and References headers if the 
         // message-id of the message we reply to is set (longer than "<>")
         // The References header should really be the old Referenced header
         // with the message ID appended, but it can be only the message ID too.
         $hdr = sqimap_get_small_header ($imap_stream, $reply_id, false);
         if(strlen($hdr->message_id) > 2) {
            $more_headers['In-Reply-To'] = $hdr->message_id;
            $more_headers['References']  = $hdr->message_id;
         }
      }

      // In order to remove the problem of users not able to create
	  // messages with "." on a blank line, RFC821 has made provision
	  // in section 4.5.2 (Transparency).
	  $body = ereg_replace("\n\\.", "\n..", $body);
	  $body = ereg_replace("^\\.", "..", $body);

      // this is to catch all plain \n instances and
      // replace them with \r\n.  
      $body = ereg_replace("\r\n", "\n", $body);
      $body = ereg_replace("\n", "\r\n", $body);
      
      if ($useSendmail) {
         $length = sendSendmail($t, $c, $b, $subject, $body, $more_headers);
      } else {
         $length = sendSMTP($t, $c, $b, $subject, $body, $more_headers);
      }

      if (sqimap_mailbox_exists ($imap_stream, $sent_folder)) {
         sqimap_append ($imap_stream, $sent_folder, $length);
         write822Header ($imap_stream, $t, $c, $b, $subject, $more_headers);
         writeBody ($imap_stream, $body);
         sqimap_append_done ($imap_stream);
      }
      sqimap_logout($imap_stream);
      // Delete the files uploaded for attaching (if any).
      ClearAttachments();
   }

?>