User authentication and authorization
This document describes the Druid security model that extensions use to enable user authentication and authorization services to Druid.
Authentication and authorization model
At the center of the Druid user authentication and authorization model are resources and actions. A resource is something that authenticated users are trying to access or modify. An action is something that users are trying to do.
Druid uses the following resource types:
- DATASOURCE – Each Druid table (i.e.,
druidschema in SQL) is a resource.
- CONFIG – Configuration resources exposed by the cluster components.
- EXTERNAL – External data read through the EXTERN function in SQL.
- STATE – Cluster-wide state resources.
- SYSTEM_TABLE – when the Broker property
druid.sql.planner.authorizeSystemTablesDirectlyis true, then Druid uses this resource type to authorize the system tables in the
sysschema in SQL.
For specific resources associated with the resource types, see Defining permissions and the corresponding endpoint descriptions in API reference.
Users perform one of the following actions on resources:
- READ – Used for read-only operations.
- WRITE – Used for operations that are not read-only.
WRITE permission on a resource does not include READ permission. If a user requires both READ and WRITE permissions on a resource, you must grant them both explicitly. For instance, a user with only
DATASOURCE READ permission
might have access to an API or a system schema record that a user with
DATASOURCE WRITE permission would not have access to.
In practice, most deployments will only need to define two classes of users:
- Administrators, who have WRITE action permissions on all resource types. These users will add datasources and administer the system.
- Data users, who only need READ access to DATASOURCE. These users should access Query APIs only through an API gateway. Other APIs and permissions include functionality that should be limited to server admins.
It is important to note that WRITE access to DATASOURCE grants a user broad access. For instance, such users will have access to the Druid file system, S3 buckets, and credentials, among other things. As such, the ability to add and manage datasources should be allocated selectively to administrators.
Default user accounts
druid.auth.authenticator.<authenticator-name>.initialAdminPassword is set, a default admin user named "admin" will be created, with the specified initial password. If this configuration is omitted, the "admin" user will not be created.
druid.auth.authenticator.<authenticator-name>.initialInternalClientPassword is set, a default internal system user named "druid_system" will be created, with the specified initial password. If this configuration is omitted, the "druid_system" user will not be created.
Each Authorizer will always have a default "admin" and "druid_system" user with full privileges.
You define permissions that you then grant to user groups. Permissions are defined by resource type, action, and resource name. This section describes the resource names available for each resource type.
Resource names for this type are datasource names. Specifying a datasource permission allows the administrator to grant users access to specific datasources.
There are two possible resource names for the "CONFIG" resource type, "CONFIG" and "security". Granting a user access to CONFIG resources allows them to access the following endpoints.
"CONFIG" resource name covers the following endpoints:
"security" resource name covers the following endpoint:
The EXTERNAL resource type only accepts the resource name "EXTERNAL". Granting a user access to EXTERNAL resources allows them to run queries that include the EXTERN function in SQL to read external data.
There is only one possible resource name for the "STATE" config resource type, "STATE". Granting a user access to STATE resources allows them to access the following endpoints.
"STATE" resource name covers the following endpoints:
|all process types|
Resource names for this type are system schema table names in the
sys schema in SQL, for example
sys.server_segments. Druid only enforces authorization for
SYSTEM_TABLE resources when the Broker property
druid.sql.planner.authorizeSystemTablesDirectly is true.
For information on what HTTP methods are supported on a particular request endpoint, refer to API reference.
GET requests require READ permissions, while
DELETE requests require WRITE permissions.
Queries on Druid datasources require DATASOURCE READ permissions for the specified datasource.
Queries to access external data through the EXTERN function require EXTERNAL READ permissions.
Queries on INFORMATION_SCHEMA tables return information about datasources that the caller has DATASOURCE READ access to. Other datasources are omitted.
Queries on the system schema tables require the following permissions:
segments: Druid filters segments according to DATASOURCE READ permissions.
servers: The user requires STATE READ permissions.
server_segments: The user requires STATE READ permissions. Druid filters segments according to DATASOURCE READ permissions.
tasks: Druid filters tasks according to DATASOURCE READ permissions.
supervisors: Druid filters supervisors according to DATASOURCE READ permissions.
When the Broker property
druid.sql.planner.authorizeSystemTablesDirectly is true, users also require
SYSTEM_TABLE authorization on a system schema table to query it.
To prevent excessive load on the Coordinator, the Authenticator and Authorizer user/role Druid metadata store state is cached on each Druid process.
Each process will periodically poll the Coordinator for the latest Druid metadata store state, controlled by the
When a configuration update occurs, the Coordinator can optionally notify each process with the updated Druid metadata store state. This behavior is controlled by the
cacheNotificationTimeout properties on Authenticators and Authorizers.
Note that because of the caching, changes made to the user/role Druid metadata store may not be immediately reflected at each Druid process.