Authorization

When interacting with Incus over the Unix socket, members of the incus-admin group will have full access to the Incus API. Those who are only members of the incus group will instead be restricted to a single project tied to their user.

When interacting with Incus over the network (see How to expose Incus to the network for instructions), it is possible to further authenticate and restrict user access. There are three supported authorization methods:

TLS authorization

Incus natively supports restricting Trusted TLS clients to one or more projects. When a client certificate is restricted, the client will also be prevented from performing global configuration changes or altering the configuration (limits, restrictions) of the projects it’s allowed access to.

To restrict access, use incus config trust edit <fingerprint>. Set the restricted key to true and specify a list of projects to restrict the client to. If the list of projects is empty, the client will not be allowed access to any of them.

This authorization method is used if a client authenticates with TLS even if OpenFGA authorization is configured.

Open Fine-Grained Authorization (OpenFGA)

Incus supports integrating with OpenFGA. This authorization method is highly granular. For example, it can be used to restrict user access to a single instance.

To use OpenFGA for authorization, you must configure and run an OpenFGA server yourself. To enable this authorization method in Incus, set the openfga.* server configuration options. Incus will connect to the OpenFGA server, write the OpenFGA model, and query this server for authorization for all subsequent requests.

OpenFGA model

With OpenFGA, access to a particular API resource is determined by the user’s relationship to it. These relationships are determined by an OpenFGA authorization model. The Incus OpenFGA authorization model describes API resources in terms of their relationship to other resources, and a relationship a user or group might have with that resource.

The full Incus OpenFGA authorization model is defined in internal/server/auth/driver_openfga_model.openfga:

model
  schema 1.1
type user

type group
  relations
    define member: [user]

type certificate
  relations
    define server: [server]
    define can_edit: [user, group#member] or admin from server
    define can_view: viewer from server

type image
  relations
    define project: [project]
    define can_edit: [user, group#member] or operator from project
    define can_view: [user, group#member] or can_edit or viewer from project

type image_alias
  relations
    define project: [project]
    define can_edit: [user, group#member] or operator from project
    define can_view: [user, group#member] or can_edit or viewer from project

type instance
  relations
    define project: [project]
    define admin: [user, group#member] or admin from project
    define operator: [user, group#member] or admin or operator from project
    define user: [user, group#member] or operator or user from project
    define viewer: [user, group#member] or user or viewer from project
    define can_access_console: [user, group#member] or user
    define can_access_files: [user, group#member] or user
    define can_connect_sftp: [user, group#member] or user
    define can_edit: operator
    define can_exec: [user, group#member] or user
    define can_manage_backups: [user, group#member] or operator
    define can_manage_snapshots: [user, group#member] or operator
    define can_update_state: [user, group#member] or operator
    define can_view: viewer

type network
  relations
    define project: [project]
    define can_edit: [user, group#member] or operator from project
    define can_view: [user, group#member] or can_edit or viewer from project

type network_acl
  relations
    define project: [project]
    define can_edit: [user, group#member] or operator from project
    define can_view: [user, group#member] or can_edit or viewer from project

type network_integration
  relations
    define server: [server]
    define can_edit: [user, group#member] or admin from server
    define can_view: viewer from server

type network_zone
  relations
    define project: [project]
    define can_edit: [user, group#member] or operator from project
    define can_view: [user, group#member] or can_edit or viewer from project

type profile
  relations
    define project: [project]
    define can_edit: [user, group#member] or operator from project
    define can_view: [user, group#member] or can_edit or viewer from project

type project
  relations
    define server: [server]
    define admin: [user, group#member] or admin from server
    define operator: [user, group#member] or admin or operator from server
    define user: [user, group#member] or operator or user from server
    define viewer: [user, group#member] or user or viewer from server
    define can_create_image_aliases: [user, group#member] or operator
    define can_create_images: [user, group#member] or operator
    define can_create_instances: [user, group#member] or operator
    define can_create_network_acls: [user, group#member] or operator
    define can_create_networks: [user, group#member] or operator
    define can_create_network_zones: [user, group#member] or operator
    define can_create_profiles: [user, group#member] or operator
    define can_create_storage_buckets: [user, group#member] or operator
    define can_create_storage_volumes: [user, group#member] or operator
    define can_edit: admin
    define can_view_events: [user, group#member] or viewer
    define can_view_operations: [user, group#member] or viewer
    define can_view: viewer

type server
  relations
    define admin: [user, group#member]
    define operator: [user, group#member] or admin
    define user: [user, group#member] or operator
    define viewer: [user, group#member] or user
    define authenticated: [user:*]
    define can_create_certificates: [user, group#member] or admin
    define can_create_network_integrations: [user, group#member] or admin
    define can_create_projects: [user, group#member] or admin
    define can_create_storage_pools: [user, group#member] or admin
    define can_edit: admin
    define can_override_cluster_target_restriction: [user, group#member] or admin
    define can_view_privileged_events: [user, group#member] or admin
    define can_view_metrics: authenticated
    define can_view_resources: authenticated
    define can_view_sensitive: [user, group#member] or viewer
    define can_view: authenticated

type storage_bucket
  relations
    define project: [project]
    define can_edit: [user, group#member] or operator from project
    define can_view: [user, group#member] or can_edit or viewer from project

type storage_pool
  relations
    define server: [server]
    define can_edit: [user, group#member] or admin from server
    define can_view: authenticated from server

type storage_volume
  relations
    define project: [project]
    define can_edit: [user, group#member] or operator from project
    define can_manage_backups: [user, group#member] or can_edit
    define can_manage_snapshots: [user, group#member] or can_edit
    define can_view: [user, group#member] or can_edit or viewer from project

Important

Users that you do not trust with root access to the host should not be granted the following relations:

  • server -> admin

  • server -> operator

  • server -> can_edit

  • server -> can_create_storage_pools

  • server -> can_create_projects

  • server -> can_create_certificates

  • certificate -> can_edit

  • storage_pool -> can_edit

  • project -> manager

The remaining relations may be granted. However, you must apply appropriate Project restrictions.

Scriptlet authorization

Incus supports defining a scriptlet to manage fine-grained authorization, allowing to write precise authorization rules with no dependency on external tools.

To use scriptlet authorization, you can write a scriptlet in the authorization.scriptlet server configuration option implementing a function authorize, which takes three arguments:

  • details, an object with attributes Username (the user name or certificate fingerprint), Protocol (the authentication protocol), IsAllProjectsRequest (whether the request is made on all projects) and ProjectName (the project name)

  • object, the object on which the user requests authorization

  • entitlement, the authorization level asked by the user

This function must return a Boolean indicating whether the user has access or not to the given object with the given entitlement.

Additionally, two optional functions can be defined so that users can be listed through the access API:

  • get_instance_access, with two arguments (project_name and instance_name), returning a list of users able to access a given instance

  • get_project_access, with one argument (project_name), returning a list of users able to access a given project