Barbican Documentation

WHAT IS BARBICAN?

Barbican is the OpenStack Key Manager service. It provides secure storage, provisioning and management of secret data. This includes keying material such as Symmetric Keys, Asymmetric Keys, Certificates and raw binary data.

API GUIDE

If youre trying to learn how to use barbican, you can start by reading about Secrets in the Barbican API Guide. Once youre comfortable working with secrets you can dig into the rest of the API.

Cloud Administrator Guide – Key Manager service

The Key Manager service, code-named Barbican, is the default secret storage service for OpenStack. The service provides secure storage, provisioning and management of secrets.

Access Control Role Based Access Control (RBAC)

Like many other services, the Key Manager service supports the protection of its APIs by enforcing policy rules defined in a policy file. The Key Manager service stores a reference to a policy JSON file in its configuration file, /etc/barbican/barbican.conf. Typically this file is named policy.yaml and it is stored in /etc/barbican/policy.yaml. Each Key Manager API call has a line in the policy file that dictates which level of access applies:
API_NAME: RULE_STATEMENT or MATCH_STATEMENT

where RULE_STATEMENT can be another RULE_STATEMENT or a MATCH_STATEMENT:
RULE_STATEMENT: RULE_STATEMENT or MATCH_STATEMENT

MATCH_STATEMENT is a set of identifiers that must match between the token provided by the caller of the API and the parameters or target entities of the API in question. For example:
“secrets:post”: “role:admin or role:creator”

indicates that to create a new secret via a POST request, you must have either the admin or creator role in your token.

Warning: The Key Manager service scopes the ownership of a secret at the project level. This means that many calls in the API will perform an additional check to ensure that the project_id of the token matches the project_id stored as the secret owner.

Default Policy

The policy engine in OpenStack is very flexible and allows for customized policies that make sense for your particular cloud. The Key Manager service comes with a sample policy.yaml file which can be used as the starting point for a customized policy. The sample policy defines 5 distinct roles:

• key-manager: service-admin The cloud administrator in charge of the Key Manager service. This user has access to all management APIs like the project-quotas.
• admin Project administrator. This user has full access to all resources owned by the project for which the admin role is scoped.
• creator Users with this role are allowed to create new resources and can also delete resources which are owned by the project for which the creator role is scoped. They are also allowed full access to existing secrets owned by the project in scope.
• observer Users with this role are allowed to access to existing resources but are not allowed to upload new secrets or delete existing secrets.
• audit Users with this role are only allowed access to the resource metadata. So users with this role are unable to decrypt secrets.

Access Control List API

There are some limitations that result from scoping ownership of a secret at the project level. For example, it is not possible to grant a user access to a single secret, as granting a role on a project would allow access to all all secrets owned by that project.

Additionally, there is no easy way to upload a private secret (i.e. a secret that only you have access to) without creating a new project for which only you have roles assigned on it.

To address these limitations the Key Manager service includes an Access Control List (ACL) API. For full details see the ACL API User Guide