deb-glance/doc/source/policies.rst

Policies

Glance's public API calls may be restricted to certain sets of users using a policy configuration file. This document explains exactly how policies are configured and what they apply to.

A policy is composed of a set of rules that are used by the policy "Brain" in determining if a particular action may be performed by the authorized tenant.

Constructing a Policy Configuration File

A policy configuration file is a simply JSON object that contain sets of rules. Each top-level key is the name of a rule. Each rule is a string that describes an action that may be performed in the Glance API.

The actions that may have a rule enforced on them are:

• get_images - List available image entities
  • GET /v1/images
  • GET /v1/images/detail
  • GET /v2/images
• get_image - Retrieve a specific image entity
  • HEAD /v1/images/<IMAGE_ID>
  • GET /v1/images/<IMAGE_ID>
  • GET /v2/images/<IMAGE_ID>
• download_image - Download binary image data
  • GET /v1/images/<IMAGE_ID>
  • GET /v2/images/<IMAGE_ID>/file
• add_image - Create an image entity
  • POST /v1/images
  • POST /v2/images
• modify_image - Update an image entity
  • PUT /v1/images/<IMAGE_ID>
  • PUT /v2/images/<IMAGE_ID>
• publicize_image - Create or update images with attribute
  • POST /v1/images with attribute is_public = true
  • PUT /v1/images/<IMAGE_ID> with attribute is_public = true
  • POST /v2/images with attribute visibility = public
  • PUT /v2/images/<IMAGE_ID> with attribute visibility = public
• delete_image - Delete an image entity and associated binary data
  • DELETE /v1/images/<IMAGE_ID>
  • DELETE /v2/images/<IMAGE_ID>
• manage_image_cache - Allowed to use the image cache management API

To limit an action to a particular role or roles, you list the roles like so :

{
  "delete_image": ["role:admin", "role:superuser"]
}

The above would add a rule that only allowed users that had roles of either "admin" or "superuser" to delete an image.

Examples

Example 1. (The default policy configuration)

{
    "default": []
}

Note that an empty JSON list means that all methods of the Glance API are callable by anyone.

Example 2. Disallow modification calls to non-admins

{
    "default": [],
    "add_image": ["role:admin"],
    "modify_image": ["role:admin"],
    "delete_image": ["role:admin"]
}