Description:
In order to prevent unnecessary project ownership assignments to users/service-accounts and further misuses of projects and resources, all 'roles/Owner' assignments should be monitored.
Members (users/Service-Accounts) with a role assignment to primitive role 'roles/Owner' are project owners.
The project owner has all the privileges on the project the role belongs to. These are summarized below:
Granting the owner role to a member (user/Service-Account) will allow that member to modify the Identity and Access Management (IAM) policy. Therefore, grant the owner role only if the member has a legitimate purpose to manage the IAM policy. This is because the project IAM policy contains sensitive access control data. Having a minimal set of users allowed to manage IAM policy will simplify any auditing that may be necessary.
Rationale:
Project ownership has the highest level of privileges on a project. To avoid misuse of project resources, the project ownership assignment/change actions mentioned above should be monitored and alerted to concerned recipients.
Enabling of logging may result in your project being charged for the additional logs usage.
From Google Cloud Console
Create the prescribed log metric:
Go to 'Logging/Logs-based Metrics' by visiting https://console.cloud.google.com/logs/metrics and click "CREATE METRIC".
Click the down arrow symbol on the 'Filter Bar' at the rightmost corner and select 'Convert to Advanced Filter'.
Clear any text and add:
(protoPayload.serviceName="cloudresourcemanager.googleapis.com")
AND (ProjectOwnership OR projectOwnerInvitee)
OR (protoPayload.serviceData.policyDelta.bindingDeltas.action="REMOVE"
AND protoPayload.serviceData.policyDelta.bindingDeltas.role="roles/owner")
OR (protoPayload.serviceData.policyDelta.bindingDeltas.action="ADD"
AND protoPayload.serviceData.policyDelta.bindingDeltas.role="roles/owner")
Click 'Submit Filter'. The logs display based on the filter text entered by the user.
In the 'Metric Editor' menu on the right, fill out the name field. Set 'Units' to '1' (default) and the 'Type' to 'Counter'. This ensures that the log metric counts the number of log entries matching the advanced logs query.
Click 'Create Metric'.
Create the display prescribed Alert Policy:
Identify the newly created metric under the section 'User-defined Metrics' at https://console.cloud.google.com/logs/metrics.
Click the 3-dot icon in the rightmost column for the desired metric and select 'Create alert from Metric'. A new page opens.
Fill out the alert policy configuration and click 'Save'. Choose the alerting threshold and configuration that makes sense for the user's organization. For example, a threshold of zero(0) for the most recent value will ensure that a notification is triggered for every owner change in the project:
Set 'Aggregator' to 'Count'
Set 'Configuration':
Condition: above
Threshold: 0
For: most recent value
Configure the desired notifications channels in the section 'Notifications'.
Name the policy and click 'Save'.
From Google Cloud CLI
Create a prescribed Log Metric:
Create prescribed Alert Policy