raspap-webgui/includes/admin.php

<?php

include_once( 'includes/status_messages.php' );

function DisplayAuthConfig($username, $password){
  $status = new StatusMessages();
  if (isset($_POST['UpdateAdminPassword'])) {
    if (CSRFValidate()) {
      if (password_verify($_POST['oldpass'], $password)) {
        $new_username=trim($_POST['username']);
        if ($_POST['newpass'] != $_POST['newpassagain']) {
          $status->addMessage('New passwords do not match', 'danger');
        } else if ($new_username == '') {
          $status->addMessage('Username must not be empty', 'danger');
        } else {
          if ($auth_file = fopen(RASPI_ADMIN_DETAILS, 'w')) {
            fwrite($auth_file, $new_username.PHP_EOL);
            fwrite($auth_file, password_hash($_POST['newpass'], PASSWORD_BCRYPT).PHP_EOL);
            fclose($auth_file);
            $username = $new_username;
            $status->addMessage('Admin password updated');
          } else {
            $status->addMessage('Failed to update admin password', 'danger');
          }
        }
      } else {
        $status->addMessage('Old password does not match', 'danger');
      }
    } else {
      error_log('CSRF violation');
    }
  }
?>
  <div class="row">
    <div class="col-lg-12">
      <div class="panel panel-primary">
        <div class="panel-heading"><i class="fa fa-lock fa-fw"></i>Configure Auth</div>
        <div class="panel-body">
          <p><?php $status->showMessages(); ?></p>
          <form role="form" action="/?page=auth_conf" method="POST">
            <?php CSRFToken() ?>
            <div class="row">
              <div class="form-group col-md-4">
                <label for="username">Username</label>
                <input type="text" class="form-control" name="username" value="<?php echo $username; ?>"/>
              </div>
            </div>
            <div class="row">
              <div class="form-group col-md-4">
                <label for="password">Old password</label>
                <input type="password" class="form-control" name="oldpass"/>
              </div>
            </div>
            <div class="row">
              <div class="form-group col-md-4">
                <label for="password">New password</label>
                <input type="password" class="form-control" name="newpass"/>
              </div>
            </div>
            <div class="row">
              <div class="form-group col-md-4">
                <label for="password">Repeat new password</label>
                <input type="password" class="form-control" name="newpassagain"/>
              </div>
            </div>
            <input type="submit" class="btn btn-outline btn-primary" name="UpdateAdminPassword" value="Save settings" />
          </form>
        </div><!-- /.panel-body -->
      </div><!-- /.panel-default -->
    </div><!-- /.col-lg-12 -->
  </div><!-- /.row -->
<?php 
}

?>