14 KiB
Identity concepts
- Authentication
-
The process of confirming the identity of a user. To confirm an incoming request, OpenStack Identity validates a set of credentials users supply. Initially, these credentials are a user name and password, or a user name and API key. When OpenStack Identity validates user credentials, it issues an authentication token. Users provide the token in subsequent requests.
- Credentials
-
Data that confirms the identity of the user. For example, user name and password, user name and API key, or an authentication token that the Identity service provides.
- Domain
-
An Identity service API v3 entity. Domains are a collection of projects and users that define administrative boundaries for managing Identity entities. Domains can represent an individual, company, or operator-owned space. They expose administrative activities directly to system users. Users can be granted the administrator role for a domain. A domain administrator can create projects, users, and groups in a domain and assign roles to users and groups in a domain.
- Endpoint
-
A network-accessible address, usually a URL, through which you can access a service. If you are using an extension for templates, you can create an endpoint template that represents the templates of all consumable services that are available across the regions.
- Group
-
An Identity service API v3 entity. Groups are a collection of users owned by a domain. A group role, granted to a domain or project, applies to all users in the group. Adding or removing users to or from a group grants or revokes their role and authentication to the associated domain or project.
- OpenStackClient
-
A command-line interface for several OpenStack services including the Identity API. For example, a user can run the
openstack service create
andopenstack endpoint create
commands to register services in their OpenStack installation. - Project
-
A container that groups or isolates resources or identity objects. Depending on the service operator, a project might map to a customer, account, organization, or tenant.
- Region
-
An Identity service API v3 entity. Represents a general division in an OpenStack deployment. You can associate zero or more sub-regions with a region to make a tree-like structured hierarchy. Although a region does not have a geographical connotation, a deployment can use a geographical name for a region, such as
us-east
. - Role
-
A personality with a defined set of user rights and privileges to perform a specific set of operations. The Identity service issues a token to a user that includes a list of roles. When a user calls a service, that service interprets the user role set, and determines to which operations or resources each role grants access.
- Service
-
An OpenStack service, such as Compute (nova), Object Storage (swift), or Image service (glance), that provides one or more endpoints through which users can access resources and perform operations.
- Token
-
An alpha-numeric text string that enables access to OpenStack APIs and resources. A token may be revoked at any time and is valid for a finite duration. While OpenStack Identity supports token-based authentication in this release, it intends to support additional protocols in the future. OpenStack Identity is an integration service that does not aspire to be a full-fledged identity store and management solution.
- User
-
A digital representation of a person, system, or service that uses OpenStack cloud services. The Identity service validates that incoming requests are made by the user who claims to be making the call. Users have a login and can access resources by using assigned tokens. Users can be directly assigned to a particular project and behave as if they are contained in that project.
User management
Identity user management examples:
Create a user named
alice
:$ openstack user create --password-prompt --email alice@example.com alice
Create a project named
acme
:$ openstack project create acme --domain default
Create a domain named
emea
:$ openstack --os-identity-api-version=3 domain create emea
Create a role named
compute-user
:$ openstack role create compute-user
Note
Individual services assign meaning to roles, typically through limiting or granting access to users with the role to the operations that the service supports. Role access is typically configured in the service's
policy.json
file. For example, to limit Compute access to thecompute-user
role, edit the Compute service'spolicy.json
file to require this role for Compute operations.
The Identity service assigns a project and a role to a user. You
might assign the compute-user
role to the
alice
user in the acme
project:
$ openstack role add --project acme --user alice compute-user
A user can have different roles in different projects. For example,
Alice might also have the admin
role in the
Cyberdyne
project. A user can also have multiple roles in
the same project.
The /etc/[SERVICE_CODENAME]/policy.json
file controls
the tasks that users can perform for a given service. For example, the
/etc/nova/policy.json
file specifies the access policy for
the Compute service, the /etc/glance/policy.json
file
specifies the access policy for the Image service, and the
/etc/keystone/policy.json
file specifies the access policy
for the Identity service.
The default policy.json
files in the Compute, Identity,
and Image services recognize only the admin
role. Any user
with any role in a project can access all operations that do not require
the admin
role.
To restrict users from performing operations in, for example, the
Compute service, you must create a role in the Identity service and then
modify the /etc/nova/policy.json
file so that this role is
required for Compute operations.
For example, the following line in the
/etc/cinder/policy.json
file does not restrict which users
can create volumes:
"volume:create": "",
If the user has any role in a project, he can create volumes in that project.
To restrict the creation of volumes to users who have the
compute-user
role in a particular project, you add
"role:compute-user"
:
"volume:create": "role:compute-user",
To restrict all Compute service requests to require this role, the resulting file looks like:
{
"admin_or_owner": "role:admin or project_id:%(project_id)s",
"default": "rule:admin_or_owner",
"compute:create": "role:compute-user",
"compute:create:attach_network": "role:compute-user",
"compute:create:attach_volume": "role:compute-user",
"compute:get_all": "role:compute-user",
"compute:unlock_override": "rule:admin_api",
"admin_api": "role:admin",
"compute_extension:accounts": "rule:admin_api",
"compute_extension:admin_actions": "rule:admin_api",
"compute_extension:admin_actions:pause": "rule:admin_or_owner",
"compute_extension:admin_actions:unpause": "rule:admin_or_owner",
"compute_extension:admin_actions:suspend": "rule:admin_or_owner",
"compute_extension:admin_actions:resume": "rule:admin_or_owner",
"compute_extension:admin_actions:lock": "rule:admin_or_owner",
"compute_extension:admin_actions:unlock": "rule:admin_or_owner",
"compute_extension:admin_actions:resetNetwork": "rule:admin_api",
"compute_extension:admin_actions:injectNetworkInfo": "rule:admin_api",
"compute_extension:admin_actions:createBackup": "rule:admin_or_owner",
"compute_extension:admin_actions:migrateLive": "rule:admin_api",
"compute_extension:admin_actions:migrate": "rule:admin_api",
"compute_extension:aggregates": "rule:admin_api",
"compute_extension:certificates": "role:compute-user",
"compute_extension:cloudpipe": "rule:admin_api",
"compute_extension:console_output": "role:compute-user",
"compute_extension:consoles": "role:compute-user",
"compute_extension:createserverext": "role:compute-user",
"compute_extension:deferred_delete": "role:compute-user",
"compute_extension:disk_config": "role:compute-user",
"compute_extension:evacuate": "rule:admin_api",
"compute_extension:extended_server_attributes": "rule:admin_api",
"compute_extension:extended_status": "role:compute-user",
"compute_extension:flavorextradata": "role:compute-user",
"compute_extension:flavorextraspecs": "role:compute-user",
"compute_extension:flavormanage": "rule:admin_api",
"compute_extension:floating_ip_dns": "role:compute-user",
"compute_extension:floating_ip_pools": "role:compute-user",
"compute_extension:floating_ips": "role:compute-user",
"compute_extension:hosts": "rule:admin_api",
"compute_extension:keypairs": "role:compute-user",
"compute_extension:multinic": "role:compute-user",
"compute_extension:networks": "rule:admin_api",
"compute_extension:quotas": "role:compute-user",
"compute_extension:rescue": "role:compute-user",
"compute_extension:security_groups": "role:compute-user",
"compute_extension:server_action_list": "rule:admin_api",
"compute_extension:server_diagnostics": "rule:admin_api",
"compute_extension:simple_tenant_usage:show": "rule:admin_or_owner",
"compute_extension:simple_tenant_usage:list": "rule:admin_api",
"compute_extension:users": "rule:admin_api",
"compute_extension:virtual_interfaces": "role:compute-user",
"compute_extension:virtual_storage_arrays": "role:compute-user",
"compute_extension:volumes": "role:compute-user",
"compute_extension:volume_attachments:index": "role:compute-user",
"compute_extension:volume_attachments:show": "role:compute-user",
"compute_extension:volume_attachments:create": "role:compute-user",
"compute_extension:volume_attachments:delete": "role:compute-user",
"compute_extension:volumetypes": "role:compute-user",
"volume:create": "role:compute-user",
"volume:get_all": "role:compute-user",
"volume:get_volume_metadata": "role:compute-user",
"volume:get_snapshot": "role:compute-user",
"volume:get_all_snapshots": "role:compute-user",
"network:get_all_networks": "role:compute-user",
"network:get_network": "role:compute-user",
"network:delete_network": "role:compute-user",
"network:disassociate_network": "role:compute-user",
"network:get_vifs_by_instance": "role:compute-user",
"network:allocate_for_instance": "role:compute-user",
"network:deallocate_for_instance": "role:compute-user",
"network:validate_networks": "role:compute-user",
"network:get_instance_uuids_by_ip_filter": "role:compute-user",
"network:get_floating_ip": "role:compute-user",
"network:get_floating_ip_pools": "role:compute-user",
"network:get_floating_ip_by_address": "role:compute-user",
"network:get_floating_ips_by_project": "role:compute-user",
"network:get_floating_ips_by_fixed_address": "role:compute-user",
"network:allocate_floating_ip": "role:compute-user",
"network:deallocate_floating_ip": "role:compute-user",
"network:associate_floating_ip": "role:compute-user",
"network:disassociate_floating_ip": "role:compute-user",
"network:get_fixed_ip": "role:compute-user",
"network:add_fixed_ip_to_instance": "role:compute-user",
"network:remove_fixed_ip_from_instance": "role:compute-user",
"network:add_network_to_project": "role:compute-user",
"network:get_instance_nw_info": "role:compute-user",
"network:get_dns_domains": "role:compute-user",
"network:add_dns_entry": "role:compute-user",
"network:modify_dns_entry": "role:compute-user",
"network:delete_dns_entry": "role:compute-user",
"network:get_dns_entries_by_address": "role:compute-user",
"network:get_dns_entries_by_name": "role:compute-user",
"network:create_private_dns_domain": "role:compute-user",
"network:create_public_dns_domain": "role:compute-user",
"network:delete_dns_domain": "role:compute-user"
}
Service management
The Identity service provides identity, token, catalog, and policy services. It consists of:
- keystone Web Server Gateway Interface (WSGI) service
-
Can be run in a WSGI-capable web server such as Apache httpd to provide the Identity service. The service and administrative APIs are run as separate instances of the WSGI service.
- Identity service functions
-
Each has a pluggable back end that allow different ways to use the particular service. Most support standard back ends like LDAP or SQL.
The Identity service also maintains a user that corresponds to each
service, such as, a user named nova
for the Compute
service, and a special service project called service
.
For information about how to create services and endpoints, see the OpenStack Administrator Guide <https://docs.openstack.org/keystone/latest/ admin/cli-keystone-manage-services.html>__.
Groups
A group is a collection of users in a domain. Administrators can create groups and add users to them. A role can then be assigned to the group, rather than individual users. Groups were introduced with the Identity API v3.
Identity API V3 provides the following group-related operations:
- Create a group
- Delete a group
- Update a group (change its name or description)
- Add a user to a group
- Remove a user from a group
- List group members
- List groups for a user
- Assign a role on a project to a group
- Assign a role on a domain to a group
- Query role assignments to groups
Note
The Identity service server might not allow all operations. For example, if you use the Identity server with the LDAP Identity back end and group updates are disabled, a request to create, delete, or update a group fails.
Here are a couple of examples:
- Group A is granted Role A on Project A. If User A is a member of Group A, when User A gets a token scoped to Project A, the token also includes Role A.
- Group B is granted Role B on Domain B. If User B is a member of Group B, when User B gets a token scoped to Domain B, the token also includes Role B.