squirrelmail/functions/imap_general.php

<?php

/**
 *   imap.php
 *
 *   Copyright (c) 1999-2001 The SquirrelMail Development Team
 *   Licensed under the GNU GPL. For full terms see the file COPYING.
 *
 *   This implements all functions that do general imap functions.
 *
 *   $Id$
 */

/*****************************************************************/
/*** THIS FILE NEEDS TO HAVE ITS FORMATTING FIXED!!!           ***/
/*** PLEASE DO SO AND REMOVE THIS COMMENT SECTION.             ***/
/***    + Base level indent should begin at left margin, as    ***/
/***      the function definition and comments start below.    ***/
/***    + All identation should consist of four space blocks   ***/
/***    + Tab characters are evil.                             ***/
/***    + all comments should use "slash-star ... star-slash"  ***/
/***      style -- no pound characters, no slash-slash style   ***/
/***    + FLOW CONTROL STATEMENTS (if, while, etc) SHOULD      ***/
/***      ALWAYS USE { AND } CHARACTERS!!!                     ***/
/***    + Please use ' instead of ", when possible. Note "     ***/
/***      should always be used in _( ) function calls.        ***/
/*** Thank you for your help making the SM code more readable. ***/
/*****************************************************************/

/**
 * Unique SessionId
 *
 * Sets an unique session id in order to avoid simultanous sessions crash.
 *
 * @return	string	a 4 chars unique string
 */
function sqimap_session_id() {

        global $data_dir, $username;

        $IMAPSessionID = substr(session_id(), -4);
        if( $IMAPSessionID == '' ) {
            $IMAPSessionID = 'A001';
        }

        return( $IMAPSessionID );
   }


   /******************************************************************************
    **  Reads the output from the IMAP stream.  If handle_errors is set to true,
    **  this will also handle all errors that are received.  If it is not set,
    **  the errors will be sent back through $response and $message
    ******************************************************************************/

   function sqimap_read_data_list ($imap_stream, $pre, $handle_errors,
                                   &$response, &$message) {
      global $color, $squirrelmail_language;

      $read = '';
      $resultlist = array();

      $more_msgs = true;
      while ($more_msgs) {
         $data = array();
         $total_size = 0;
         while (strpos($read, "\n") === false) {
            $read .= fgets($imap_stream, 9096);
         }

         if (ereg("^\\* [0-9]+ FETCH.*\\{([0-9]+)\\}", $read, $regs)) {
            $size = $regs[1];
         } else if (ereg("^\\* [0-9]+ FETCH", $read, $regs)) {
            // Sizeless response, probably single-line
            $size = -1;
            $data[] = $read;
            $read = fgets($imap_stream, 9096);
         } else {
            $size = -1;
         }
         while (1) {
            while (strpos($read, "\n") === false) {
               $read .= fgets($imap_stream, 9096);
            }
            // If we know the size, no need to look at the end parameters
            if ($size > 0) {
               if ($total_size == $size) {
                  // We've reached the end of this 'message', switch to the next one.
                  $data[] = $read;
                  break;
               } else if ($total_size > $size) {
                  $difference = $total_size - $size;
                  $total_size = $total_size - strlen($read);
                  $data[] = substr ($read, 0, strlen($read)-$difference);
                  $read = substr ($read, strlen($read)-$difference, strlen($read));
                  break;
               } else {
                  $data[] = $read;
                  $read = fgets($imap_stream, 9096);
                  while (strpos($read, "\n") === false) {
                      $read .= fgets($imap_stream, 9096);
                  }
               }
               $total_size += strlen($read);
            } else {
               if (ereg("^$pre (OK|BAD|NO)(.*)", $read, $regs) ||
                   (($size == -1) && ereg("^\\* [0-9]+ FETCH.*", $read, $regs))) {
                  break;
               } else {
                  $data[] = $read;
                  $read = fgets ($imap_stream, 9096);
               }
            }
         }

         while (($more_msgs = !ereg("^$pre (OK|BAD|NO)(.*)$", $read, $regs)) &&
                !ereg("^\\* [0-9]+ FETCH.*", $read, $regs)) {
            $read = fgets($imap_stream, 9096);
         }
         $resultlist[] = $data;
      }
      $response = $regs[1];
      $message = trim($regs[2]);
      
      if ($handle_errors == false) { return $resultlist; }
     
      if ($response == 'NO') {
         // ignore this error from m$ exchange, it is not fatal (aka bug)
         if (strstr($message, 'command resulted in') === false) {
            set_up_language($squirrelmail_language);
            echo "<br><b><font color=$color[2]>\n";
            echo _("ERROR : Could not complete request.");
            echo "</b><br>\n";
            echo _("Reason Given: ");
            echo $message . "</font><br>\n";
            exit;
         }
      } else if ($response == 'BAD') {
         set_up_language($squirrelmail_language);
         echo "<br><b><font color=$color[2]>\n";
         echo _("ERROR : Bad or malformed request.");
         echo "</b><br>\n";
         echo _("Server responded: ");
         echo $message . "</font><br>\n";
         exit;
      }
      return $resultlist;
   }

   function sqimap_read_data ($imap_stream, $pre, $handle_errors, &$response, &$message) {
        $res = sqimap_read_data_list($imap_stream, $pre, $handle_errors, $response, $message);
        return $res[0];
   }

   /******************************************************************************
    **  Logs the user into the imap server.  If $hide is set, no error messages
    **  will be displayed.  This function returns the imap connection handle.
    ******************************************************************************/
   function sqimap_login ($username, $password, $imap_server_address, $imap_port, $hide) {
      
      global $color, $squirrelmail_language, $HTTP_ACCEPT_LANGUAGE, $onetimepad;

      $imap_stream = fsockopen ( $imap_server_address, $imap_port,
                                 $error_number, $error_string, 15);
      $server_info = fgets ($imap_stream, 1024);
        
      // Decrypt the password
      $password = OneTimePadDecrypt($password, $onetimepad);

      /** Do some error correction **/
      if (!$imap_stream) {
         if (!$hide) {
            set_up_language($squirrelmail_language, true);
            printf (_("Error connecting to IMAP server: %s.")."<br>\r\n", $imap_server_address);
            echo "$error_number : $error_string<br>\r\n";
         }
         exit;
      }

      fputs ($imap_stream, sqimap_session_id() . ' LOGIN "' . quoteIMAP($username) .
         '" "' . quoteIMAP($password) . "\"\r\n");
      $read = sqimap_read_data ($imap_stream, sqimap_session_id(), false, $response, $message);

      /** If the connection was not successful, lets see why **/
      if ($response != "OK") {
         if (!$hide) {
            if ($response != 'NO') {
               // "BAD" and anything else gets reported here.
               set_up_language($squirrelmail_language, true);
               if ($response == 'BAD')
                   printf (_("Bad request: %s")."<br>\r\n", $message);
               else
                   printf (_("Unknown error: %s") . "<br>\n", $message);
               echo '<br>';
               echo _("Read data:") . "<br>\n";
               if (is_array($read))
               {
                       foreach ($read as $line)
                       {
                           echo htmlspecialchars($line) . "<br>\n";
                        }
               }
               exit;
            } else {
               // If the user does not log in with the correct
               // username and password it is not possible to get the
               // correct locale from the user's preferences.
               // Therefore, apply the same hack as on the login
               // screen.

               // $squirrelmail_language is set by a cookie when
               // the user selects language and logs out

               set_up_language($squirrelmail_language, true);

               ?>
                  <html>
                     <body bgcolor="ffffff">
                        <br>
                        <center>
                        <table width="70%" noborder bgcolor="ffffff" align="center">
                           <tr>
                              <td bgcolor="dcdcdc">
                                 <font color="cc0000">
                                 <center>
                                 <?php echo _("ERROR") ?>
                                 </center>
                                 </font>
                              </td>
                           </tr>
                           <tr>
                              <td>
                                 <center>
                                 <?php echo _("Unknown user or password incorrect.") ?><br>
                                 <a href="login.php" target="_top"><?php echo _("Click here to try again") ?></a>
                                 </center>
                              </td>
                           </tr>
                        </table>
                        </center>
                     </body>
                  </html>
               <?php
               session_destroy();
               exit;
            }
         } else {
            exit;
         }
      }

      return $imap_stream;
   }


   
   
   /******************************************************************************
    **  Simply logs out the imap session
    ******************************************************************************/
   function sqimap_logout ($imap_stream) {
      fputs ($imap_stream, sqimap_session_id() . " LOGOUT\r\n");
   }

   function sqimap_capability($imap_stream, $capability) {
        global $sqimap_capabilities;

        if (!is_array($sqimap_capabilities)) {
            fputs ($imap_stream, sqimap_session_id() . " CAPABILITY\r\n");
            $read = sqimap_read_data($imap_stream, sqimap_session_id(), true, $a, $b);

            $c = explode(' ', $read[0]);
            for ($i=2; $i < count($c); $i++) {
                $cap_list = explode('=', $c[$i]);
                if (isset($cap_list[1]))
                    $sqimap_capabilities[$cap_list[0]] = $cap_list[1];
                else
                    $sqimap_capabilities[$cap_list[0]] = TRUE;
            }
        }
        if (! isset($sqimap_capabilities[$capability]))
        return false;
        return $sqimap_capabilities[$capability];
    }

   /******************************************************************************
    **  Returns the delimeter between mailboxes:  INBOX/Test, or INBOX.Test... 
    ******************************************************************************/
   function sqimap_get_delimiter ($imap_stream = false) {

      global $sqimap_delimiter;
      global $optional_delimiter;

      /* Use configured delimiter if set */
      if((!empty($optional_delimiter)) && $optional_delimiter != "detect")
         return $optional_delimiter;

      /* Do some caching here */
      if (!$sqimap_delimiter) {
        if (sqimap_capability($imap_stream, "NAMESPACE")) {
            /* According to something that I can't find, this is supposed to work on all systems
            OS: This won't work in Courier IMAP.
            OS:  According to rfc2342 response from NAMESPACE command is:
            OS:  * NAMESPACE (PERSONAL NAMESPACES) (OTHER_USERS NAMESPACE) (SHARED NAMESPACES)
            OS:  We want to lookup all personal NAMESPACES...
            */
            fputs ($imap_stream, sqimap_session_id() . " NAMESPACE\r\n");
            $read = sqimap_read_data($imap_stream, sqimap_session_id(), true, $a, $b);
            if (eregi('\\* NAMESPACE +(\\( *\\(.+\\) *\\)|NIL) +(\\( *\\(.+\\) *\\)|NIL) +(\\( *\\(.+\\) *\\)|NIL)', $read[0], $data)) {
                if (eregi('^\\( *\\((.*)\\) *\\)', $data[1], $data2))
                    $pn = $data2[1];
                $pna = explode(')(', $pn);
                while (list($k, $v) = each($pna))
                {
                    $lst = explode('"', $v);
                    if (isset($lst[3])) {
                        $pn[$lst[1]] = $lst[3];
                    } else {
                        $pn[$lst[1]] = '';
                    }
                }
            }
            $sqimap_delimiter = $pn[0];
        } else {
            fputs ($imap_stream, ". LIST \"INBOX\" \"\"\r\n");
            $read = sqimap_read_data($imap_stream, '.', true, $a, $b);
            $quote_position = strpos ($read[0], '"');
            $sqimap_delimiter = substr ($read[0], $quote_position+1, 1);
        }
    }
    return $sqimap_delimiter;
   }


   /******************************************************************************
    **  Gets the number of messages in the current mailbox. 
    ******************************************************************************/
   function sqimap_get_num_messages ($imap_stream, $mailbox) {
      fputs ($imap_stream, sqimap_session_id() . " EXAMINE \"$mailbox\"\r\n");
      $read_ary = sqimap_read_data ($imap_stream, sqimap_session_id(), true, $result, $message);
      for ($i = 0; $i < count($read_ary); $i++) {
         if (ereg("[^ ]+ +([^ ]+) +EXISTS", $read_ary[$i], $regs)) {
            return $regs[1];
         }
      }
      return "BUG!  Couldn't get number of messages in $mailbox!";
   }

   
   /******************************************************************************
    **  Returns a displayable email address 
    ******************************************************************************/
   function sqimap_find_email ($string) {
      /** Luke Ehresman <lehresma@css.tayloru.edu>
       ** <lehresma@css.tayloru.edu>
       ** lehresma@css.tayloru.edu
       **
       ** What about
       **    lehresma@css.tayloru.edu (Luke Ehresman)
       **/

      if (ereg("<([^>]+)>", $string, $regs)) {
          $string = $regs[1];
      }
      return trim($string); 
   }

   
   /******************************************************************************
    **  Takes the From: field, and creates a displayable name.
    **    Luke Ehresman <lkehresman@yahoo.com>
    **           becomes:   Luke Ehresman
    **    <lkehresman@yahoo.com>
    **           becomes:   lkehresman@yahoo.com
    ******************************************************************************/
   function sqimap_find_displayable_name ($string) {
      $string = ' '.trim($string);
      $orig_string = $string;
      if (strpos($string, '<') && strpos($string, '>')) {
         if (strpos($string, '<') == 1) {
            $string = sqimap_find_email($string);
         } else {
            $string = trim($string);
            $string = substr($string, 0, strpos($string, '<'));
            $string = ereg_replace ('"', '', $string);   
         }   

         if (trim($string) == '') {
            $string = sqimap_find_email($orig_string);
         }
      }
      return $string; 
   }


   /******************************************************************************
    **  Returns the number of unseen messages in this folder 
    ******************************************************************************/
   function sqimap_unseen_messages ($imap_stream, $mailbox) {
      //fputs ($imap_stream, sqimap_session_id() . " SEARCH UNSEEN NOT DELETED\r\n");
      fputs ($imap_stream, sqimap_session_id() . " STATUS \"$mailbox\" (UNSEEN)\r\n");
      $read_ary = sqimap_read_data ($imap_stream, sqimap_session_id(), true, $result, $message);
      ereg("UNSEEN ([0-9]+)", $read_ary[0], $regs);
      return $regs[1];
   }
 
  
   /******************************************************************************
    **  Saves a message to a given folder -- used for saving sent messages
    ******************************************************************************/
   function sqimap_append ($imap_stream, $sent_folder, $length) {
      fputs ($imap_stream, sqimap_session_id() . " APPEND \"$sent_folder\" (\\Seen) \{$length}\r\n");
      $tmp = fgets ($imap_stream, 1024);
   } 

   function sqimap_append_done ($imap_stream) {
      fputs ($imap_stream, "\r\n");
      $tmp = fgets ($imap_stream, 1024);
   }
?>