Access control for organization resources with IAM

Google Cloud offers Identity and Access Management (IAM), which lets you give more granular access to specific Google Cloud resources and prevents unwanted access to other resources. IAM lets you adopt the security principle of least privilege, so you grant only the necessary access to your resources.

IAM lets you control who (users) has what access (roles) to which resources by setting IAM policies. IAM policies grant specific role(s) to a user giving the user certain permissions.

This page explains the IAM roles that are available at the organization resource level, and how to create and manage IAM policies for organization resources using the Cloud Resource Manager API. For a detailed description of IAM, read the IAM documentation. In particular, see Granting, Changing, and Revoking Access.

Permissions and roles

To control access to resources, Google Cloud requires that accounts making API requests have appropriate IAM roles. IAM roles include permissions that allow users to perform specific actions on Google Cloud resources. For example, the resourcemanager.organizations.get permission allows a user to get details about their organization resource.

You don't directly give users permissions; instead, you grant them roles, which have one or more permissions bundled within them.

You can grant one or more roles on the same resource.

Using predefined roles

The following table lists the roles that you can grant to access an organization resource's properties, the description of what the role does, and the permissions bundled within that role.

Role Permissions

(roles/resourcemanager.organizationAdmin)

Access to manage IAM policies and view organization policies for organizations, folders, and projects.

Lowest-level resources where you can grant this role:

  • Project

essentialcontacts.*

  • essentialcontacts.contacts.create
  • essentialcontacts.contacts.delete
  • essentialcontacts.contacts.get
  • essentialcontacts.contacts.list
  • essentialcontacts.contacts.send
  • essentialcontacts.contacts.update

orgpolicy.constraints.list

orgpolicy.policies.list

orgpolicy.policy.get

resourcemanager.folders.get

resourcemanager.folders.getIamPolicy

resourcemanager.folders.list

resourcemanager.folders.setIamPolicy

resourcemanager.organizations.*

  • resourcemanager.organizations.get
  • resourcemanager.organizations.getIamPolicy
  • resourcemanager.organizations.setIamPolicy

resourcemanager.projects.get

resourcemanager.projects.getIamPolicy

resourcemanager.projects.list

resourcemanager.projects.setIamPolicy

(roles/resourcemanager.organizationViewer)

Provides access to view an organization.

Lowest-level resources where you can grant this role:

  • Organization

resourcemanager.organizations.get

(roles/orgpolicy.policyAdmin)

Provides access to define what restrictions an organization wants to place on the configuration of cloud resources by setting Organization Policies.

Lowest-level resources where you can grant this role:

  • Organization

orgpolicy.*

  • orgpolicy.constraints.list
  • orgpolicy.customConstraints.create
  • orgpolicy.customConstraints.delete
  • orgpolicy.customConstraints.get
  • orgpolicy.customConstraints.list
  • orgpolicy.customConstraints.update
  • orgpolicy.policies.create
  • orgpolicy.policies.delete
  • orgpolicy.policies.list
  • orgpolicy.policies.update
  • orgpolicy.policy.get
  • orgpolicy.policy.set

policysimulator.orgPolicyViolations.list

policysimulator.orgPolicyViolationsPreviews.*

  • policysimulator.orgPolicyViolationsPreviews.create
  • policysimulator.orgPolicyViolationsPreviews.get
  • policysimulator.orgPolicyViolationsPreviews.list

(roles/browser)

Read access to browse the hierarchy for a project, including the folder, organization, and allow policy. This role doesn't include permission to view resources in the project.

Lowest-level resources where you can grant this role:

  • Project

resourcemanager.folders.get

resourcemanager.folders.list

resourcemanager.organizations.get

resourcemanager.projects.get

resourcemanager.projects.getIamPolicy

resourcemanager.projects.list

Creating custom roles

In addition to the predefined roles described in this topic, you can also create custom roles that are collections of permissions that you tailor to your needs. When creating a custom role for use with Resource Manager, be aware of the following points:
  • List and get permissions, such as resourcemanager.projects.get/list, should always be granted as a pair.
  • When your custom role includes the folders.list and folders.get permissions, it should also include projects.list and projects.get.
  • Be aware that the setIamPolicy permission for organization, folder, and project resources allows the user to grant all other permissions, and so should be assigned with care.

Viewing existing access for an organization resource

You can view what roles a user is granted for an organization resource to by getting the organization-resource-level IAM policy. You can view a policy of an organization resource using the Google Cloud console, the Google Cloud CLI, or the getIamPolicy() method.

Console

To view granted roles at the organization resource level using the Google Cloud console:

  1. Go to the Manage resources page in the Google Cloud console:

    Open the Manage resources page

  2. On the Organization drop-down list, select your organization resource.

  3. Select the check box for the organization resource.

  4. On the right side Info Panel, under Permissions, click to expand a role and display all members who have that role.

gcloud

Get the IAM policy for the organization resource using the get-iam-policy command:

gcloud alpha organizations get-iam-policy [ORGANIZATION_ID] --format json >
[FILENAME.JSON]

The command outputs the policy, which will be similar to the following:

bindings:
- members:
- user:testuser1@gcp-test.com
role: roles/editor
- members:
- user:admin@gcp-test.com
role:roles/resourcemanager.organizationAdmin
- members:
- user:testuser2@gcp-test.com
role: roles/resourcemanager.projectCreator
etag": "BwU1aRxWk30="

API

The following code snippet returns the policy for the organization resource https://cloudresourcemanager.googleapis.com/v3/organizations/12345.

Request:

POST
https://cloudresourcemanager.googleapis.com/v3/organizations/12345:getIamPolicy

Response:

{
    "bindings": [
    {
        "role": "roles/resourcemanager.organizationAdmin",
        "members": [
        "user:email1@gmail.com"
    ]
    },
    {
        "role": "roles/resourcemanager.projectCreator",
        "members": [
            "user:email2@gmail.com",
            "user:email3@gmail.com",
            "serviceAccount:my-other-app@appspot.gserviceaccount.com"
        ]
    }
    ]
    "etag": "BwUjHYKHHiQ="
}

Python

The method getIamPolicy() allows you to get a policy that was previously set.

crm = discovery.build(
    'cloudresourcemanager', 'v3', http=creds.authorize(httplib2.Http()))
policy = crm.organizations().getIamPolicy(
    resource=flags.organizationId, body={}).execute()
print json.dumps(policy, indent=2)

Granting access to an organization resource

Organization Administrators can grant IAM roles to team members so that they can access an organization's resources and APIs. You can grant roles to a Google Account email, a Google Group, a service account, or a G Suite domain. You can use the Google Cloud console, the gcloud CLI, or the setIamPolicy() method to grant roles.

Console

To set access control at the organization resource level using the Google Cloud console:

  1. Go to the Manage resources page in the Google Cloud console:

    Open the Manage resources page

  2. On the Organization drop-down list, select your organization resource.

  3. Select the check box for the organization resource. If you do not have a Folder resource, the organization resource will not be visible. To continue, see the instructions for granting roles through the IAM page.

  4. If the Info Panel pane on the right is hidden, click Show Info Panel in the top right corner.

  5. In the Info Panel pane, in the Permissions tab, click Add Member.

  6. In the New members field, enter the team members you want to add. You can designate a Google Account email, a Google Group, a service account, or a G Suite domain.

  7. In the Select a role drop-down list, select the role you want to grant to the team members.

  8. Click Add.

gcloud

To set an organization resource's IAM policy using the gcloud command:

  1. Get the IAM policy for the organization resource using the get-iam-policy command and output the policy to a JSON file:

    gcloud alpha organizations get-iam-policy [ORGANIZATION_ID]
    --format json > [FILENAME.JSON]
    
  2. The contents of the JSON file will look similar to the following:

    {
        "bindings": [
        {
            "members": [
                "user:testuser1@gcp-test.com"
            ],
            "role": "roles/editor"
        },
        {
            "members": [
                "user:admin@gcp-test.com",
            ],
            "role": "roles/resourcemanager.organizationAdmin"
        },
        {
            "members": [
                "user:testuser2@gcp-test.com"
            ],
            "role": "roles/resourcemanager.projectCreator"
        },
        ],
        "etag": "BwU1aRxWk30="
    }
    
  3. Using a text editor, open the JSON file and add a new entry to the bindings array that defines Organization Administrator. For example to make anotheradmin@gcp-test.com an Organization Administrator, you would change the example shown above as follows:

    {
        "bindings": [
        {
            "members": [
                "user:testuser1@gcp-test.com"
            ],
            "role": "roles/editor"
        },
        {
            "members": [
                "user:admin@gcp-test.com",
                "user:anotheradmin@gcp-test.com"
            ],
            "role": "roles/resourcemanager.organizationAdmin"
        },
        {
            "members": [
                "user:testuser20@gcp-test.com"
            ],
            "role": "roles/resourcemanager.projectCreator"
        },
        ],
        "etag": "BwU1aRxWk30="
    }
    
  4. Update the organization resource's policy by running the following command:

    gcloud alpha organizations set-iam-policy [ORGANIZATION_ID] policy.json
    

API

Request:

POST https://cloudresourcemanager.googleapis.com/v3/organizations/12345:setIamPolicy
{
    "policy": {
    "version": "0",
    "bindings": [
    {
        "role": "roles/resourcemanager.organizationAdmin",
        "members": [
            "user:email1@gmail.com"
        ]
    },
    {
        "role": "roles/resourcemanager.projectCreator",
        "members": [
        "user:email2@gmail.com",
        "user:email3@gmail.com",
        "serviceAccount:my-other-app@appspot.gserviceaccount.com"
        ]
    }
    ]
    "etag": "BwUjHYKHHiQ="
    }
}

Response:

{
    "bindings": [
    {
        "role": "roles/resourcemanager.organizationAdmin",
        "members": [
            "user:email1@gmail.com"
        ]
    },
    {
        "role": "roles/resourcemanager.projectCreator",
        "members": [
            "user:email2@gmail.com",
            "user:email3@gmail.com",
            "serviceAccount:my-other-app@appspot.gserviceaccount.com"
        ]
    }
    ]
    "etag": "BwUjHYKJUiQ="
}

The setIamPolicy() method allows you grant roles to users by attaching an IAM policy to the organization resource. The IAM policy is a collection of statements that define who has what access.

Read-Modify-Write: A common pattern for updating a resource's metadata, such as the Policy is to read its current state, update the data locally, and then send the modified data for writing. This pattern may result in a conflict if two or more independent processes attempt the sequence simultaneously. For example, say there are two owners for a project and both of them are attempting to make conflicting changes to the policy at the same time. The changes made by one of the project owners could fail in some cases. IAM solves this problem using an etag property in IAM policies. This property is used to verify whether the policy has changed since the last request. When you make a request to IAM with an etag value, IAM compares the etag value in the request with the existing etag value associated with the policy. It writes the policy only if the etag values match.

When you update a policy, first get the policy using getIamPolicy(), update the policy, and then write the updated policy using setIamPolicy(). Use the etag value when setting the policy only if the corresponding policy in GetPolicyResponse contains an etag value.

Python

The setIamPolicy() method lets you attach a policy to a resource. The setIamPolicy method takes a SetIamPolicyRequest, which contains a policy to be set and the resource to which the policy is attached. It returns the resulting policy. It is recommended to follow the read-modify-write pattern when updating a policy using setIamPolicy().

Here is some sample code to set a policy for an organization resource:

crm = discovery.build(
    'cloudresourcemanager', 'v3', http=creds.authorize(httplib2.Http()))
policy = crm.organizations().getIamPolicy(
    resource=flags.organizationId, body={}).execute()

admin_binding = next(
    (binding
        for binding in policy['bindings']
        if binding['role'] == 'roles/resourcemanager.organizationAdmin'),
        None)

# Add an empty Organization Administrator binding if not present.
if not admin_binding:
    admin_binding = {
        'role': 'roles/resourcemanager.organizationAdmin',
        'members': []
    }
policy['bindings'].append(admin_binding)

# Add the new Admin (if necessary).
new_admin = 'user:' + flags.adminEmail
if new_admin not in admin_binding['members']:
    admin_binding['members'].append(new_admin)
policy = crm.organizations().setIamPolicy(
    resource=flags.organizationId,
    body={
        'resource': flags.organizationId,
        'policy': policy
    }).execute()

print json.dumps(policy, indent=2)

Restricting project visibility for users

Users can see all projects they have access to in the Google Cloud console and in search queries, regardless of whether or not they are in the user's currently selected organization resource. You can use the Organization Policy Service to restrict the set of projects that are returned in queries and in the Google Cloud console. This can be used to restrict users to only see projects within your own domain.

The Organization Policy constraint constraints/resourcemanager.accessBoundaries is a list constraint that is enforced on your organization resource. The constraint accepts a list of organization resource IDs, which define the set of organization resources that make their resources visible to users in a query or the Google Cloud console.

Projects appear under No organization if the user does not have the resourcemanager.organizations.get permission on the parent organization resource of the project. This can make it seem like a project that is not part of your organization resource is not associated with an organization resource at all. If you use the resourcemanager.accessBoundaries constraint to disallow an organization resource, projects that belong to that organization resource will not appear at all in queries or in the Google Cloud console. Any project that has not yet been migrated to an organization resource will not be visible if this constraint is enforced.

We recommend migrating projects that are under No organization to your organization resource before enforcing this constraint. For information about migrating projects into an organization resource, see Moving a project.

For information on setting an organization policy, see Using constraints.

Testing permissions

You can test IAM permissions on a user for an organization resource with the testIamPermissions() method. This method takes the resource URL and the set of permissions you want to test as input parameters, and returns the subset of these permissions that the user has access to.

You typically don't invoke testIamPermission() if you're using the Google Cloud console directly to manage permissions. testIamPermissions() is intended for integration with your proprietary software such as a customized graphical user interface. For example, the Google Cloud console uses testIamPermissions() internally to determine which UI should be available to the logged-in user.

API

You can use the testIamPermissions() method to check which of the given permissions the caller has for the given resource. This method takes a resource name and a set of permissions as parameters, and returns the subset of permissions that the caller has.

Here is some sample code to test permissions for an organization resource:

Request:

POST https://cloudresourcemanager.googleapis.com/v3/organizations/12345:testIamPermissions

{
    "permissions":  [
        "resourcemanager.organizations.get",
        "resourcemanager.organizations.setIamPolicy"
    ]
}

Response:

{
    "permissions": [
        "resourcemanager.organizations.get"
    ]
}

Python

crm = discovery.build(
    'cloudresourcemanager', 'v3', http=creds.authorize(httplib2.Http()))

response = crm.organizations().testIamPermissions(
    resource=flags.organizationId,
    body={
        'resource': flags.organizationId,
        'permissions': [
            'resourcemanager.organizations.setIamPolicy',
            'resourcemanager.projects.patch'
        ]
    }).execute()

print json.dumps(response, indent=2)