Important Note on Verifying Secure Execution Host Key Documents

The certificates of the host key signing keys that are needed to verify host key documents will expire on April 24, 2024 for IBM z15 and LinuxONE III and on March 29, 2024 for IBM z16 and LinuxONE 4. Due to a requirement from the Certificate Authority (DigiCert), the renewed certificates are equipped with a new Locality value (“Armonk” instead of “Poughkeepsie”). These renewed certificates cause the current versions of the genprotimg, pvattest, and pvsecret tools to fail the verification of host key documents.

The IBM Z team is preparing updates of the genprotimg, pvattest, and pvsecret tools to accept the new certificates and is working with Linux distribution partners to release the updated tools.

To build new Secure Execution images, attestation requests, or add-secret requests before the updated tools are available in Linux distributions, follow these steps:

Step 1:

Obtain the host key document, the host key signing key certificate, the intermediate certificate from the Certificate Authority, and the list of revoked host keys (CRL):

• For IBM z15 and LinuxONE III, see https://www.ibm.com/support/resourcelink/api/content/public/secure-execution-gen1.html

• For IBM z16 and LinuxONE 4, see https://www.ibm.com/support/resourcelink/api/content/public/secure-execution-gen2.html
  
  

Step 2: 

Download the script check_hostkeydoc from https://github.com/ibm-s390-linux/s390-tools/blob/master/genprotimg/samples/check_hostkeydoc.

Step 3:

Verify each host key document using the check_hostkeydoc script. For example, issue

# ./check_hostkeydoc HKD1234.crt ibm-z-host-key-signing.crt \ -c DigiCertCA.crt -r ibm-z-host-key.crl

This example verifies the host key document HKD1234.crt using the host key signing key certificate ibm-z-host-key-signing.crt, and the intermediate certificate of the Certificate Authority DigiCertCA.crt,as well as the list of revoked host keys ibm-z-host-key.crl.

After the host key documents are verified using the check_hostkeydoc script, you can safely call genprotimg, pvattest, or pvsecret with the –-no-verify option.

For a description about how to manually verify host key documents, see https://www.ibm.com/docs/en/linux-on-z?topic=execution-verify-host-key-document.