RoundCube 0.6

External html login:

<form name='form' action="https://domain.com/index.php" method="post">
  <p><label for="_user">Email</label><input name="_user" id="_user" value="" type="text" /></p>
  <p><label for="_pass">Password</label><input name="_pass" id="_pass" value="" type="password" /></p>
  <p>
    <input type="hidden" name="autodetect" value="0" />
    <input type="hidden" name="logged" value="1" />
    <input type="hidden" name="_action" value="login" />
    <input type="hidden" name="_task" value="login">
    <input type="hidden" name="_timezone" value="_default_">
    <input type="hidden" name="_url" value="">
    <input class="button" name="submit" id="submit" value="Log on" type="submit" />
  </p>
</form>


In config/main.inc.php:

$rcmail_config['plugins'] = array('password', 'http_authentication');




In plugins/http_authentication/http_authentication.php:

  function authenticate($args)
  {
    // Allow entering other user data in login form,
    // e.g. after log out (#1487953)
    if (!empty($args['user'])) {
        return $args;
    }

    if (!empty($_SERVER['PHP_AUTH_USER']) && !empty($_SERVER['PHP_AUTH_PW'])) {
      $args['user'] = $_SERVER['PHP_AUTH_USER'];
      $args['pass'] = $_SERVER['PHP_AUTH_PW'];
    }

    $args['cookiecheck'] = false;
    $args['valid'] = true;

    return $args;
  }