Role-Based Access Control (RBAC)

The Role-Based Access Control (RBAC) policy framework enables both operators and users to grant access to resources for specific projects.

Supported objects for sharing with specific projects

Currently, the access that can be granted using this feature is supported by:

  • Regular port creation permissions on networks (since Liberty).

  • Binding QoS policies permissions to networks or ports (since Mitaka).

  • Attaching router gateways to networks (since Mitaka).

  • Binding security groups to ports (since Stein).

  • Assigning address scopes to subnet pools (since Ussuri).

  • Assigning subnet pools to subnets (since Ussuri).

  • Assigning address groups to security group rules (since Wallaby).

Sharing an object with specific projects

Sharing an object with a specific project is accomplished by creating a policy entry that permits the target project the access_as_shared action on that object.

Sharing a network with specific projects

Create a network to share:

$ openstack network create secret_network
+---------------------------+--------------------------------------+
| Field                     | Value                                |
+---------------------------+--------------------------------------+
| admin_state_up            | UP                                   |
| availability_zone_hints   |                                      |
| availability_zones        |                                      |
| created_at                | 2017-01-25T20:16:40Z                 |
| description               |                                      |
| dns_domain                | None                                 |
| id                        | f55961b9-3eb8-42eb-ac96-b97038b568de |
| ipv4_address_scope        | None                                 |
| ipv6_address_scope        | None                                 |
| is_default                | None                                 |
| mtu                       | 1450                                 |
| name                      | secret_network                       |
| port_security_enabled     | True                                 |
| project_id                | 61b7eba037fd41f29cfba757c010faff     |
| provider:network_type     | vxlan                                |
| provider:physical_network | None                                 |
| provider:segmentation_id  | 9                                    |
| qos_policy_id             | None                                 |
| revision_number           | 3                                    |
| router:external           | Internal                             |
| segments                  | None                                 |
| shared                    | False                                |
| status                    | ACTIVE                               |
| subnets                   |                                      |
| tags                      | []                                   |
| updated_at                | 2017-01-25T20:16:40Z                 |
+---------------------------+--------------------------------------+

Create the policy entry using the openstack network rbac create command (in this example, the ID of the project we want to share with is b87b2fc13e0248a4a031d38e06dc191d):

$ openstack network rbac create --target-project \
b87b2fc13e0248a4a031d38e06dc191d --action access_as_shared \
--type network f55961b9-3eb8-42eb-ac96-b97038b568de
+-------------------+--------------------------------------+
| Field             | Value                                |
+-------------------+--------------------------------------+
| action            | access_as_shared                     |
| id                | f93efdbf-f1e0-41d2-b093-8328959d469e |
| name              | None                                 |
| object_id         | f55961b9-3eb8-42eb-ac96-b97038b568de |
| object_type       | network                              |
| project_id        | 61b7eba037fd41f29cfba757c010faff     |
| target_project_id | b87b2fc13e0248a4a031d38e06dc191d     |
+-------------------+--------------------------------------+

The target-project parameter specifies the project that requires access to the network. The action parameter specifies what the project is allowed to do. The type parameter says that the target object is a network. The final parameter is the ID of the network we are granting access to.

Project b87b2fc13e0248a4a031d38e06dc191d will now be able to see the network when running openstack network list and openstack network show and will also be able to create ports on that network. No other users (other than admins and the owner) will be able to see the network.

Note

Subnets inherit the RBAC policy entries of their network.

To remove access for that project, delete the policy that allows it using the openstack network rbac delete command:

$ openstack network rbac delete f93efdbf-f1e0-41d2-b093-8328959d469e

If that project has ports on the network, the server will prevent the policy from being deleted until the ports have been deleted:

$ openstack network rbac delete f93efdbf-f1e0-41d2-b093-8328959d469e
RBAC policy on object f93efdbf-f1e0-41d2-b093-8328959d469e
cannot be removed because other objects depend on it.

This process can be repeated any number of times to share a network with an arbitrary number of projects.

Sharing a QoS policy with specific projects

Create a QoS policy to share:

$ openstack network qos policy create secret_policy
+-------------------+--------------------------------------+
| Field             | Value                                |
+-------------------+--------------------------------------+
| description       |                                      |
| id                | 1f730d69-1c45-4ade-a8f2-89070ac4f046 |
| name              | secret_policy                        |
| project_id        | 61b7eba037fd41f29cfba757c010faff     |
| revision_number   | 1                                    |
| rules             | []                                   |
| shared            | False                                |
| tags              | []                                   |
+-------------------+--------------------------------------+

Create the RBAC policy entry using the openstack network rbac create command (in this example, the ID of the project we want to share with is be98b82f8fdf46b696e9e01cebc33fd9):

$ openstack network rbac create --target-project \
be98b82f8fdf46b696e9e01cebc33fd9 --action access_as_shared \
--type qos_policy 1f730d69-1c45-4ade-a8f2-89070ac4f046
+-------------------+--------------------------------------+
| Field             | Value                                |
+-------------------+--------------------------------------+
| action            | access_as_shared                     |
| id                | 8828e38d-a0df-4c78-963b-e5f215d3d550 |
| name              | None                                 |
| object_id         | 1f730d69-1c45-4ade-a8f2-89070ac4f046 |
| object_type       | qos_policy                           |
| project_id        | 61b7eba037fd41f29cfba757c010faff     |
| target_project_id | be98b82f8fdf46b696e9e01cebc33fd9     |
+-------------------+--------------------------------------+

The target-project parameter specifies the project that requires access to the QoS policy. The action parameter specifies what the project is allowed to do. The type parameter says that the target object is a QoS policy. The final parameter is the ID of the QoS policy we are granting access to.

Project be98b82f8fdf46b696e9e01cebc33fd9 will now be able to see the QoS policy when running openstack network qos policy list and openstack network qos policy show and will also be able to bind it to its ports or networks. No other users (other than admins and the owner) will be able to see the QoS policy.

To remove access for that project, delete the RBAC policy that allows it using the openstack network rbac delete command:

$ openstack network rbac delete 8828e38d-a0df-4c78-963b-e5f215d3d550

If that project has ports or networks with the QoS policy applied to them, the server will not delete the RBAC policy until the QoS policy is no longer in use:

$ openstack network rbac delete 8828e38d-a0df-4c78-963b-e5f215d3d550
RBAC policy on object 8828e38d-a0df-4c78-963b-e5f215d3d550
cannot be removed because other objects depend on it.

This process can be repeated any number of times to share a qos-policy with an arbitrary number of projects.

Sharing a security group with specific projects

Create a security group to share:

$ openstack security group create my_security_group
+-------------------+--------------------------------------+
| Field             | Value                                |
+-------------------+--------------------------------------+
| created_at        | 2019-02-07T06:09:59Z                 |
| description       | my_security_group                    |
| id                | 5ba835b7-22b0-4be6-bdbe-e0722d1b5f24 |
| location          | None                                 |
| name              | my_security_group                    |
| project_id        | 077e8f39d3db4c9e998d842b0503283a     |
| revision_number   | 1                                    |
| rules             | ...                                  |
| tags              | []                                   |
| updated_at        | 2019-02-07T06:09:59Z                 |
+-------------------+--------------------------------------+

Create the RBAC policy entry using the openstack network rbac create command (in this example, the ID of the project we want to share with is 32016615de5d43bb88de99e7f2e26a1e):

$ openstack network rbac create --target-project \
32016615de5d43bb88de99e7f2e26a1e --action access_as_shared \
--type security_group 5ba835b7-22b0-4be6-bdbe-e0722d1b5f24
+-------------------+--------------------------------------+
| Field             | Value                                |
+-------------------+--------------------------------------+
| action            | access_as_shared                     |
| id                | 8828e38d-a0df-4c78-963b-e5f215d3d550 |
| name              | None                                 |
| object_id         | 5ba835b7-22b0-4be6-bdbe-e0722d1b5f24 |
| object_type       | security_group                       |
| project_id        | 077e8f39d3db4c9e998d842b0503283a     |
| target_project_id | 32016615de5d43bb88de99e7f2e26a1e     |
+-------------------+--------------------------------------+

The target-project parameter specifies the project that requires access to the security group. The action parameter specifies what the project is allowed to do. The type parameter says that the target object is a security group. The final parameter is the ID of the security group we are granting access to.

Project 32016615de5d43bb88de99e7f2e26a1e will now be able to see the security group when running openstack security group list and openstack security group show and will also be able to bind it to its ports. No other users (other than admins and the owner) will be able to see the security group.

To remove access for that project, delete the RBAC policy that allows it using the openstack network rbac delete command:

$ openstack network rbac delete 8828e38d-a0df-4c78-963b-e5f215d3d550

If that project has ports with the security group applied to them, the server will not delete the RBAC policy until the security group is no longer in use:

$ openstack network rbac delete 8828e38d-a0df-4c78-963b-e5f215d3d550
RBAC policy on object 8828e38d-a0df-4c78-963b-e5f215d3d550
cannot be removed because other objects depend on it.

This process can be repeated any number of times to share a security-group with an arbitrary number of projects.

Creating an instance which uses a security group shared through RBAC, but only specifying the network ID when calling Nova will not work currently. In such cases Nova will check if the given security group exists in Neutron before it creates a port in the given network. The problem with that is that Nova asks only for the security groups filtered by the project_id thus it will not get the shared security group back from the Neutron API. See bug 1942615 for details. To workaround the issue, the user needs to create a port in Neutron first, and then pass that port to Nova:

$ openstack port create --network net1 --security-group
5ba835b7-22b0-4be6-bdbe-e0722d1b5f24 shared-sg-port

$ openstack server create --image cirros-0.5.1-x86_64-disk --flavor m1.tiny
--port shared-sg-port vm-with-shared-sg

Sharing an address scope with specific projects

Create an address scope to share:

$ openstack address scope create my_address_scope
+-------------------+--------------------------------------+
| Field             | Value                                |
+-------------------+--------------------------------------+
| id                | c19cb654-3489-4160-9c82-8a3015483643 |
| ip_version        | 4                                    |
| location          | ...                                  |
| name              | my_address_scope                     |
| project_id        | 34304bc4f233470fa4a2448d153b6324     |
| shared            | False                                |
+-------------------+--------------------------------------+

Create the RBAC policy entry using the openstack network rbac create command (in this example, the ID of the project we want to share with is 32016615de5d43bb88de99e7f2e26a1e):

$ openstack network rbac create --target-project \
32016615de5d43bb88de99e7f2e26a1e --action access_as_shared \
--type address_scope c19cb654-3489-4160-9c82-8a3015483643
+-------------------+--------------------------------------+
| Field             | Value                                |
+-------------------+--------------------------------------+
| action            | access_as_shared                     |
| id                | d54b1482-98c4-44aa-9115-ede80387ffe0 |
| location          | ...                                  |
| name              | None                                 |
| object_id         | c19cb654-3489-4160-9c82-8a3015483643 |
| object_type       | address_scope                        |
| project_id        | 34304bc4f233470fa4a2448d153b6324     |
| target_project_id | 32016615de5d43bb88de99e7f2e26a1e     |
+-------------------+--------------------------------------+

The target-project parameter specifies the project that requires access to the address scope. The action parameter specifies what the project is allowed to do. The type parameter says that the target object is an address scope. The final parameter is the ID of the address scope we are granting access to.

Project 32016615de5d43bb88de99e7f2e26a1e will now be able to see the address scope when running openstack address scope list and openstack address scope show and will also be able to assign it to its subnet pools. No other users (other than admins and the owner) will be able to see the address scope.

To remove access for that project, delete the RBAC policy that allows it using the openstack network rbac delete command:

$ openstack network rbac delete d54b1482-98c4-44aa-9115-ede80387ffe0

If that project has subnet pools with the address scope applied to them, the server will not delete the RBAC policy until the address scope is no longer in use:

$ openstack network rbac delete d54b1482-98c4-44aa-9115-ede80387ffe0
RBAC policy on object c19cb654-3489-4160-9c82-8a3015483643
cannot be removed because other objects depend on it.

This process can be repeated any number of times to share an address scope with an arbitrary number of projects.

Sharing a subnet pool with specific projects

Create a subnet pool to share:

$ openstack subnet pool create my_subnetpool --pool-prefix 203.0.113.0/24
+-------------------+--------------------------------------+
| Field             | Value                                |
+-------------------+--------------------------------------+
| address_scope_id  | None                                 |
| created_at        | 2020-03-16T14:23:01Z                 |
| default_prefixlen | 8                                    |
| default_quota     | None                                 |
| description       |                                      |
| id                | 11f79287-bc17-46b2-bfd0-2562471eb631 |
| ip_version        | 4                                    |
| is_default        | False                                |
| location          | ...                                  |
| max_prefixlen     | 32                                   |
| min_prefixlen     | 8                                    |
| name              | my_subnetpool                        |
| project_id        | 290ccedbcf594ecc8e76eff06f964f7e     |
| revision_number   | 0                                    |
| shared            | False                                |
| tags              |                                      |
| updated_at        | 2020-03-16T14:23:01Z                 |
+-------------------+--------------------------------------+

Create the RBAC policy entry using the openstack network rbac create command (in this example, the ID of the project we want to share with is 32016615de5d43bb88de99e7f2e26a1e):

$ openstack network rbac create --target-project \
32016615de5d43bb88de99e7f2e26a1e --action access_as_shared \
--type subnetpool 11f79287-bc17-46b2-bfd0-2562471eb631
+-------------------+--------------------------------------+
| Field             | Value                                |
+-------------------+--------------------------------------+
| action            | access_as_shared                     |
| id                | d54b1482-98c4-44aa-9115-ede80387ffe0 |
| location          | ...                                  |
| name              | None                                 |
| object_id         | 11f79287-bc17-46b2-bfd0-2562471eb631 |
| object_type       | subnetpool                           |
| project_id        | 290ccedbcf594ecc8e76eff06f964f7e     |
| target_project_id | 32016615de5d43bb88de99e7f2e26a1e     |
+-------------------+--------------------------------------+

The target-project parameter specifies the project that requires access to the subnet pool. The action parameter specifies what the project is allowed to do. The type parameter says that the target object is a subnet pool. The final parameter is the ID of the subnet pool we are granting access to.

Project 32016615de5d43bb88de99e7f2e26a1e will now be able to see the subnet pool when running openstack subnet pool list and openstack subnet pool show and will also be able to assign it to its subnets. No other users (other than admins and the owner) will be able to see the subnet pool.

To remove access for that project, delete the RBAC policy that allows it using the openstack network rbac delete command:

$ openstack network rbac delete d54b1482-98c4-44aa-9115-ede80387ffe0

If that project has subnets with the subnet pool applied to them, the server will not delete the RBAC policy until the subnet pool is no longer in use:

$ openstack network rbac delete d54b1482-98c4-44aa-9115-ede80387ffe0
RBAC policy on object 11f79287-bc17-46b2-bfd0-2562471eb631
cannot be removed because other objects depend on it.

This process can be repeated any number of times to share a subnet pool with an arbitrary number of projects.

Sharing an address group with specific projects

Create an address group to share:

$ openstack address group create test-ag --address 10.1.1.1
+-------------+--------------------------------------+
| Field       | Value                                |
+-------------+--------------------------------------+
| addresses   | ['10.1.1.1/32']                      |
| description |                                      |
| id          | cdb6eb3e-f9a0-4d52-8478-358eaa2c4737 |
| name        | test-ag                              |
| project_id  | 66c77cf262454777a8f455cce48c12c0     |
+-------------+--------------------------------------+

Create the RBAC policy entry using the openstack network rbac create command (in this example, the ID of the project we want to share with is bbd82892525d4372911390b984ed3265):

$ openstack network rbac create --target-project \
bbd82892525d4372911390b984ed3265 --action access_as_shared \
--type address_group cdb6eb3e-f9a0-4d52-8478-358eaa2c4737
+-------------------+--------------------------------------+
| Field             | Value                                |
+-------------------+--------------------------------------+
| action            | access_as_shared                     |
| id                | c7414ac2-9a6b-420b-84c5-4158a6cca4f9 |
| name              | None                                 |
| object_id         | cdb6eb3e-f9a0-4d52-8478-358eaa2c4737 |
| object_type       | address_group                        |
| project_id        | 66c77cf262454777a8f455cce48c12c0     |
| target_project_id | bbd82892525d4372911390b984ed3265     |
+-------------------+--------------------------------------+

The target-project parameter specifies the project that requires access to the address group. The action parameter specifies what the project is allowed to do. The type parameter says that the target object is an address group. The final parameter is the ID of the address group we are granting access to.

Project bbd82892525d4372911390b984ed3265 will now be able to see the address group when running openstack address group list and openstack address group show and will also be able to assign it to its security group rules. No other users (other than admins and the owner) will be able to see the address group.

To remove access for that project, delete the RBAC policy that allows it using the openstack network rbac delete command:

$ openstack network rbac delete c7414ac2-9a6b-420b-84c5-4158a6cca4f9

If that project has security group rules with the address group applied to them, the server will not delete the RBAC policy until the address group is no longer in use:

$ openstack network rbac delete c7414ac2-9a6b-420b-84c5-4158a6cca4f9
RBAC policy on object cdb6eb3e-f9a0-4d52-8478-358eaa2c4737
cannot be removed because other objects depend on it

This process can be repeated any number of times to share an address group with an arbitrary number of projects.

How the ‘shared’ flag relates to these entries

As introduced in other guide entries, neutron provides a means of making an object (address-scope, network, qos-policy, security-group, subnetpool) available to every project. This is accomplished using the shared flag on the supported object:

$ openstack network create global_network --share
+---------------------------+--------------------------------------+
| Field                     | Value                                |
+---------------------------+--------------------------------------+
| admin_state_up            | UP                                   |
| availability_zone_hints   |                                      |
| availability_zones        |                                      |
| created_at                | 2017-01-25T20:32:06Z                 |
| description               |                                      |
| dns_domain                | None                                 |
| id                        | 84a7e627-573b-49da-af66-c9a65244f3ce |
| ipv4_address_scope        | None                                 |
| ipv6_address_scope        | None                                 |
| is_default                | None                                 |
| mtu                       | 1450                                 |
| name                      | global_network                       |
| port_security_enabled     | True                                 |
| project_id                | 61b7eba037fd41f29cfba757c010faff     |
| provider:network_type     | vxlan                                |
| provider:physical_network | None                                 |
| provider:segmentation_id  | 7                                    |
| qos_policy_id             | None                                 |
| revision_number           | 3                                    |
| router:external           | Internal                             |
| segments                  | None                                 |
| shared                    | True                                 |
| status                    | ACTIVE                               |
| subnets                   |                                      |
| tags                      | []                                   |
| updated_at                | 2017-01-25T20:32:07Z                 |
+---------------------------+--------------------------------------+

This is the equivalent of creating a policy on the network that permits every project to perform the action access_as_shared on that network. Neutron treats them as the same thing, so the policy entry for that network should be visible using the openstack network rbac list command:

$ openstack network rbac list
+-------------------------------+-------------+--------------------------------+
| ID                            | Object Type | Object ID                      |
+-------------------------------+-------------+--------------------------------+
| 58a5ee31-2ad6-467d-           | qos_policy  | 1f730d69-1c45-4ade-            |
| 8bb8-8c2ae3dd1382             |             | a8f2-89070ac4f046              |
| 27efbd79-f384-4d89-9dfc-      | network     | 84a7e627-573b-49da-            |
| 6c4a606ceec6                  |             | af66-c9a65244f3ce              |
+-------------------------------+-------------+--------------------------------+

Use the openstack network rbac show command to see the details:

$ openstack network rbac show 27efbd79-f384-4d89-9dfc-6c4a606ceec6
+-------------------+--------------------------------------+
| Field             | Value                                |
+-------------------+--------------------------------------+
| action            | access_as_shared                     |
| id                | 27efbd79-f384-4d89-9dfc-6c4a606ceec6 |
| name              | None                                 |
| object_id         | 84a7e627-573b-49da-af66-c9a65244f3ce |
| object_type       | network                              |
| project_id        | 61b7eba037fd41f29cfba757c010faff     |
| target_project_id | *                                    |
+-------------------+--------------------------------------+

The output shows that the entry allows the action access_as_shared on object 84a7e627-573b-49da-af66-c9a65244f3ce of type network to target_tenant *, which is a wildcard that represents all projects.

Currently, the shared flag is just a mapping to the underlying RBAC policies for a network. Setting the flag to True on a network creates a wildcard RBAC entry. Setting it to False removes the wildcard entry.

When you run openstack network list or openstack network show, the shared flag is calculated by the server based on the calling project and the RBAC entries for each network. For QoS objects use openstack network qos policy list or openstack network qos policy show respectively. If there is a wildcard entry, the shared flag is always set to True. If there are only entries that share with specific projects, only the projects the object is shared to will see the flag as True and the rest will see the flag as False.

Allowing a network to be used as an external network

To make a network available as an external network for specific projects rather than all projects, use the access_as_external action.

  1. Create a network that you want to be available as an external network:

    $ openstack network create secret_external_network
    +---------------------------+--------------------------------------+
    | Field                     | Value                                |
    +---------------------------+--------------------------------------+
    | admin_state_up            | UP                                   |
    | availability_zone_hints   |                                      |
    | availability_zones        |                                      |
    | created_at                | 2017-01-25T20:36:59Z                 |
    | description               |                                      |
    | dns_domain                | None                                 |
    | id                        | 802d4e9e-4649-43e6-9ee2-8d052a880cfb |
    | ipv4_address_scope        | None                                 |
    | ipv6_address_scope        | None                                 |
    | is_default                | None                                 |
    | mtu                       | 1450                                 |
    | name                      | secret_external_network              |
    | port_security_enabled     | True                                 |
    | project_id                | 61b7eba037fd41f29cfba757c010faff     |
    | proider:network_type      | vxlan                                |
    | provider:physical_network | None                                 |
    | provider:segmentation_id  | 21                                   |
    | qos_policy_id             | None                                 |
    | revision_number           | 3                                    |
    | router:external           | Internal                             |
    | segments                  | None                                 |
    | shared                    | False                                |
    | status                    | ACTIVE                               |
    | subnets                   |                                      |
    | tags                      | []                                   |
    | updated_at                | 2017-01-25T20:36:59Z                 |
    +---------------------------+--------------------------------------+
    
  2. Create a policy entry using the openstack network rbac create command (in this example, the ID of the project we want to share with is 838030a7bf3c4d04b4b054c0f0b2b17c):

    $ openstack network rbac create --target-project \
    838030a7bf3c4d04b4b054c0f0b2b17c --action access_as_external \
    --type network 802d4e9e-4649-43e6-9ee2-8d052a880cfb
    +-------------------+--------------------------------------+
    | Field             | Value                                |
    +-------------------+--------------------------------------+
    | action            | access_as_external                   |
    | id                | afdd5b8d-b6f5-4a15-9817-5231434057be |
    | name              | None                                 |
    | object_id         | 802d4e9e-4649-43e6-9ee2-8d052a880cfb |
    | object_type       | network                              |
    | project_id        | 61b7eba037fd41f29cfba757c010faff     |
    | target_project_id | 838030a7bf3c4d04b4b054c0f0b2b17c     |
    +-------------------+--------------------------------------+
    

The target-project parameter specifies the project that requires access to the network. The action parameter specifies what the project is allowed to do. The type parameter indicates that the target object is a network. The final parameter is the ID of the network we are granting external access to.

Now project 838030a7bf3c4d04b4b054c0f0b2b17c is able to see the network when running openstack network list and openstack network show and can attach router gateway ports to that network. No other users (other than admins and the owner) are able to see the network.

To remove access for that project, delete the policy that allows it using the openstack network rbac delete command:

$ openstack network rbac delete afdd5b8d-b6f5-4a15-9817-5231434057be

If that project has router gateway ports attached to that network, the server prevents the policy from being deleted until the ports have been deleted:

$ openstack network rbac delete afdd5b8d-b6f5-4a15-9817-5231434057be
RBAC policy on object afdd5b8d-b6f5-4a15-9817-5231434057be
cannot be removed because other objects depend on it.

This process can be repeated any number of times to make a network available as external to an arbitrary number of projects.

If a network is marked as external during creation, it now implicitly creates a wildcard RBAC policy granting everyone access to preserve previous behavior before this feature was added.

$ openstack network create global_external_network --external
+---------------------------+--------------------------------------+
| Field                     | Value                                |
+---------------------------+--------------------------------------+
| admin_state_up            | UP                                   |
| availability_zone_hints   |                                      |
| availability_zones        |                                      |
| created_at                | 2017-01-25T20:41:44Z                 |
| description               |                                      |
| dns_domain                | None                                 |
| id                        | 72a257a2-a56e-4ac7-880f-94a4233abec6 |
| ipv4_address_scope        | None                                 |
| ipv6_address_scope        | None                                 |
| is_default                | None                                 |
| mtu                       | 1450                                 |
| name                      | global_external_network              |
| port_security_enabled     | True                                 |
| project_id                | 61b7eba037fd41f29cfba757c010faff     |
| provider:network_type     | vxlan                                |
| provider:physical_network | None                                 |
| provider:segmentation_id  | 69                                   |
| qos_policy_id             | None                                 |
| revision_number           | 4                                    |
| router:external           | External                             |
| segments                  | None                                 |
| shared                    | False                                |
| status                    | ACTIVE                               |
| subnets                   |                                      |
| tags                      | []                                   |
| updated_at                | 2017-01-25T20:41:44Z                 |
+---------------------------+--------------------------------------+

In the output above the standard router:external attribute is External as expected. Now a wildcard policy is visible in the RBAC policy listings:

$ openstack network rbac list --long -c ID -c Action
+--------------------------------------+--------------------+
| ID                                   | Action             |
+--------------------------------------+--------------------+
| b694e541-bdca-480d-94ec-eda59ab7d71a | access_as_external |
+--------------------------------------+--------------------+

You can modify or delete this policy with the same constraints as any other RBAC access_as_external policy.

Preventing regular users from sharing objects with each other

The default policy.yaml file will not allow regular users to share objects with every other project using a wildcard; however, it will allow them to share objects with specific project IDs.

If an operator wants to prevent normal users from doing this, the "create_rbac_policy": entry in policy.yaml can be adjusted from "" to "rule:admin_only".