============= Authorization

Presto can be configured to enable authorization support for HTTP endpoints to allow system administrators to control access to different HTTP endpoints in Presto.

Role Based Access Control

Every HTTP endpoint in Presto is secured by a set of roles and can only be accessed by identities that belong to one of those roles. There are three roles defined in Presto:

user: Users who should have access to external endpoints like those needed to launch queries, check status, get output data and provides data for UI.
internal: Internal components of Presto (like coordinator and worker) which will have access to endpoints like launching tasks on workers and fetching exchange data from another worker.
admin: System administrators who will have access to internal service endpoints like those to get node status.

Enabling Authorization

The following steps must be taken to enable authorization:

:ref:enable_authentication
:ref:configure_authorizer
:ref:configure_authorization_settings

.. _enable_authentication:

Enable Authentication ^^^^^^^^^^^^^^^^^^^^^

Presto authorization requires authentication to get the accessor's principal, so make sure you have authentication enabled.

If TLS/SSL is configured properly, use the certificate to identify the accessor.

.. code-block:: none

http-server.authentication.type=CERTIFICATE
It is also possible to specify other authentication types such as KERBEROS, PASSWORD, JWT, and OAUTH2. Additional configuration may be needed.

.. code-block:: none

node.internal-address=<authentication type>

.. _configure_authorizer:

Configure Authorizer ^^^^^^^^^^^^^^^^^^^^

To enable authorization, the interface com.facebook.airlift.http.server.Authorizer must be implemented and bound. It performs the actual authorization check based on the principal of incoming request and the allowed roles of endpoint being requested.

You can either use the preset ConfigurationBasedAuthorizer or implement your own.

Configuration-based Authorizer


This plugin allows you to turn on authorization support by specifying a mapping
from roles to a regex for matching identities. Use the following steps to start using
Configuration-based authorizer:

1. Create a role to identity regex mapping and store it in a file.

   .. code-block:: none

       user=.*
       internal=coordinator
       admin=su.*

2. Specify the path to the mapping file in ``config.properties`` file:

   .. code-block:: none

       configuration-based-authorizer.role-regex-map.file-path=<path to mapping file>

3. Install the Guice module
   ``com.facebook.airlift.http.server.ConfigurationBasedAuthorizerModule``.

.. _configure_authorization_settings:

Configure Authorization Settings
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Authorization settings are configured in the ``config.properties`` file. The
authorization on the worker and coordinator nodes are configured using the same
set of properties.

The following is an example of the properties that need to be added to the
``config.properties`` file:

.. code-block:: none

    http-server.authorization.enabled=true
    http-server.authorization.default-policy=ALLOW
    http-server.authorization.default-allowed-roles=USER,ADMIN
    http-server.authorization.allow-unsecured-requests=false

======================================================= ======================================================
Property                                                Description
======================================================= ======================================================
``http-server.authorization.enabled``                   Enable authorization for the Presto.
                                                        Should be set to ``true``. Default value is
                                                        ``false``.
``http-server.authorization.default-policy``            The default authorization policy applies to endpoints
                                                        without allowed roles specified. Can be set to
                                                        ``ALLOW``, ``DENY`` and ``DEFAULT_ROLES``.
``http-server.authorization.default-allowed-roles``     The roles allowed to access the endpoints without
                                                        explicitly specified when default-policy is set to
                                                        ``DEFAULT_ROLES``.
``http-server.authorization.allow-unsecured-requests``  Skip authorization check for unsecured requests.
                                                        Default value is ``false``.
======================================================= ======================================================

.. warning::

    ``http-server.authorization.allow-unsecured-requests`` is provided as a way to
    transition from HTTP to HTTPS with authorization and is a security hole
    since it allows unauthenticated requests to skip authorization checks. Only
    enable during the transition period and disable this setting once you have
    completed migrated to using HTTPS.