The container signature feature supports signing container images and verifying container image signatures. This feature ensures that only trusted images are deployed and prevents unauthorized images from being started. This reinforces your asset security.

Prerequisites

Complete the following operations before you use container signature.
  • A Key Management Service (KMS) key is created based on the asymmetric encryption algorithm.

    For more information about how to create a KMS key, see Create a CMK.

    Notice Only asymmetric key algorithms support the container signature feature. When you create a KMS key, set Key Spec to RSA_2048 and Purpose to Sign/Verify. For more information about the cryptographic algorithms supported by KMS, see Description of encryption algorithms supported by KMS.
  • A Kubernetes cluster is created, and the kritis-validation-hook component is installed in the cluster.

    For more information about how to create Kubernetes clusters, see Create a dedicated Kubernetes cluster.

    For more information about the kritis-validation-hook component, see kritis-validation-hook introduction.

  • If this is the first time that you use the container signature feature, you must grant Security Center the required permissions to access relevant Alibaba Cloud services. Grant permissions

Limits

Only Security Center Ultimate supports this feature. If you do not use the Ultimate edition, you must upgrade Security Center to the Ultimate edition before you can use this feature. For more information about how to purchase and upgrade Security Center, see Purchase Security Center and Upgrade and downgrade Security Center. For more information about the features that each edition supports, see Features.

Procedure

  1. Log on to the Security Center console.
  2. In the left-side navigation pane, choose Operation > Container Signature.
  3. Optional:On the Container Signature page, click the Witness tab to create a witness.
    If you have created a witness, skip this step and go to Step 4.

    On the Witness tab, click Create a witness. In the panel that appears, configure the parameters and click OK.

    The following table describes the parameters.

    Parameter Description
    Witness When you configure a security policy for the container signature feature, you must select a witness to authorize the required container. We recommend that you create an identifiable name.
    Select a certificate Select the KMS key that you created from the certificate list.
    Notice Only asymmetric key algorithms support the container signature feature. When you create a KMS key, set Key Spec to RSA_2048 and Purpose to Sign/Verify. For more information about the cryptographic algorithms supported by KMS, see Description of encryption algorithms supported by KMS.
    Description Enter the description of the witness.
  4. Create a security policy.

    On the Security Policy tab, click Add Policy. In the panel that appears, configure the parameters and click OK.

    The following table describes the parameters.

    Parameter Description
    Policy Name When you configure a security policy for the container signature feature, you must select a witness to authorize the required cluster.

    We recommend that you create an identifiable name.

    Witness Select the witness that you created from the witness list.

    For more information about how to create a witness, see Step 3.

    Application Cluster After you select the cluster group for which you want to enable the container signature feature, select the required Cluster Namespace.
    Policy Enabled Turn on this switch. The policy is automatically enabled after it is created.
    Note The switch is turned off by default. As a result, the policy does not take effect.
    Note Enter the description of the security policy.

What to do next

After you create and enable a security policy for the container signature feature, a container image that has the security policy enabled is labeled as Trusted Image.
Note The feature that displays trusted signature labels is not available.