<?php
/**
 * Pwchange Plugin: allows users to change their password via the passwd command
 *
 * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
 * @author     Dennis Wagelaar <dennis.wagelaar@vub.ac.be>
 */
// must be run within Dokuwiki
if(!defined('DOKU_INC')) die();

if (!defined('DOKU_LF')) define('DOKU_LF', "\n");
if (!defined('DOKU_TAB')) define('DOKU_TAB', "\t");
if (!defined('DOKU_PLUGIN')) define('DOKU_PLUGIN',DOKU_INC.'lib/plugins/');

define('CHPASSWD_BIN','/usr/local/sbin/chpasswd');

require_once(DOKU_PLUGIN.'syntax.php');
require_once(DOKU_INC.'inc/auth.php');

class syntax_plugin_pwchange extends DokuWiki_Syntax_Plugin {

    function getInfo() {
        return array(
                'author' => 'Dennis Wagelaar',
                'email'  => 'dennis.wagelaar@vub.ac.be',
                'date'   => '2008-11-13',
                'name'   => 'Pwchange Plugin',
                'desc'   => 'allows users to change their password via the passwd command',
                'url'    => 'http://wiki.splitbrain.org/plugin:pwchange',
                );
    }

    function getType() { return 'substition'; }
    function getPType() { return 'block'; }
    function getSort() { return 98; }

    function connectTo($mode) {
        $this->Lexer->addSpecialPattern('~~PWCHANGE.*?~~', $mode, 'plugin_pwchange');
    }

    function handle($match, $state, $pos, &$handler) {
        $match = substr($match, 2, -2); // strip markup
        list($junk, $parm) = explode(':', $match, 2);

        return array($parm);
    }            

    function render($mode, &$renderer, $data) {
        global $conf;

        list($parm) = $data;

        // prevent caching to ensure the included pages are always fresh
        $renderer->info['cache'] = false;

        if ($mode == 'xhtml' ) {
          if ( $_SERVER['REMOTE_USER']) {
            // check for password change command
            if ($_REQUEST['pwchange']) {
              // do password change
              $result = $this->_changepw();
              // print result
              $renderer->p_open();
              $renderer->strong_open();
              $renderer->doc .= $result;
              $renderer->strong_close();
              $renderer->p_close();
            }
            // and render the pwchange box
            $this->_render_pwbox($renderer);
          } else {
            $renderer->p_open();
            $renderer->strong_open();
            $renderer->doc .= 'You must be logged in to change your password!';
            $renderer->strong_close();
            $renderer->p_close();
          }
          return true;
        }

      return false;
    }

    function _changepw() {
      if (!@is_executable(CHPASSWD_BIN)) {
        return 'Error: cannot invoke chpasswd command.';
      }
      if ($_REQUEST['newpw'] != $_REQUEST['newpwverify']) {
        return 'Error: new password verification differs from new password.';
      }

      $descriptorspec = array(
         0 => array("pipe", "r"),  // stdin is a pipe that the child will read from
         1 => array("pipe", "w"),  // stdout is a pipe that the child will write to
         2 => array("pipe", "w")   // stderr is a pipe that the child will write to
      );

      //error_log('about to spawn process');
      $process = proc_open(CHPASSWD_BIN, $descriptorspec, $pipes, $cwd, $env);
      if (is_resource($process)) {
        //error_log('process spawned');
        fwrite($pipes[0], $_SERVER['REMOTE_USER'] . "\n");
        fwrite($pipes[0], $_REQUEST['oldpw'] . "\n");
        fwrite($pipes[0], $_REQUEST['newpw'] . "\n");
        //error_log('data sent');
        $out = fread($pipes[1], 8192);
        //error_log('stdout read');
        $error = fread($pipes[2], 8192);
        //error_log('stderr read');
        fclose($pipes[0]);
        //error_log('closed STDIN');
        fclose($pipes[1]);
        //error_log('closed STDOUT');
        fclose($pipes[2]);
        //error_log('closed STDERR');
        $result = proc_close($process);
        //error_log('closed proc');
        if (($result['exitcode'] != 0) || ($error != 'success')) {
          return 'Error: '.$error;
        }
      } else {
        return 'Error: could not find '.CHPASSWD_BIN.' command.';
      }

      return 'Password change successful.';
    }

    function _render_pwbox(&$renderer) {
      $renderer->doc .= '<form name="pwchange" method="post" action="' . $script . '">';
      $renderer->doc .= '<input type="hidden" name="pwchange" value="true">';
      $renderer->table_open();

      $renderer->tablerow_open();
      $renderer->tableheader_open();
      $renderer->doc .= 'Username';
      $renderer->tableheader_close();
      $renderer->tablecell_open();
      $renderer->doc .= $_SERVER['REMOTE_USER'];
      $renderer->tablecell_close();
      $renderer->tablerow_close();

      $renderer->tablerow_open();
      $renderer->tableheader_open();
      $renderer->doc .= 'Old password';
      $renderer->tableheader_close();
      $renderer->tablecell_open();
      $renderer->doc .= '<input name="oldpw" class="edit" type="password" size="10" maxlength="20">';
      $renderer->tablecell_close();
      $renderer->tablerow_close();

      $renderer->tablerow_open();
      $renderer->tableheader_open();
      $renderer->doc .= 'New password';
      $renderer->tableheader_close();
      $renderer->tablecell_open();
      $renderer->doc .= '<input name="newpw" class="edit" type="password" size="10" maxlength="20">';
      $renderer->tablecell_close();
      $renderer->tablerow_close();

      $renderer->tablerow_open();
      $renderer->tableheader_open();
      $renderer->doc .= 'Verify new password';
      $renderer->tableheader_close();
      $renderer->tablecell_open();
      $renderer->doc .= '<input name="newpwverify" class="edit" type="password" size="10" maxlength="20">';
      $renderer->tablecell_close();
      $renderer->tablerow_close();

      $renderer->tablerow_open();
      $renderer->tableheader_open();
      $renderer->doc .= ' ';
      $renderer->tableheader_close();
      $renderer->tablecell_open();
      $renderer->doc .= '<input name="submit" class="button" type="submit" value="Change password">';
      $renderer->tablecell_close();
      $renderer->tablerow_close();

      $renderer->table_close();
      $renderer->doc .= '</form>';
    }

}
// vim:ts=4:sw=4:et:enc=utf-8: