Linux Secure Boot support for agents

When Linux Secure Boot is enabled on a Deep Security Agent computer, the Linux kernel performs a signature check on kernel modules before they are installed. These Deep Security features install kernel modules:

  • Anti-Malware
  • Web Reputation
  • Firewall
  • Integrity Monitoring
  • Intrusion Prevention
  • Application Control

The Deep Security Agent is only compatible with Secure Boot on RHEL 7.

If you intend to use any of those modules on a Linux computer where Secure Boot is enabled, you must enroll the Trend Micro public key for RHEL 7 (provided during install as DS11.der) into the Linux computer's firmware so that it recognizes the Trend Micro kernel module's signature. Otherwise, the kernel module can't be installed.

Deep Security refreshes the kernel module signing key in every major release (for example, 10.0 and 11.0). To keep security features functioning when you upgrade a Deep Security Agent to a new major release, you must enroll the new public key into any Linux computers that have Secure Boot enabled. You may see "Engine Offline" error message in the Deep Security Manager console because the operating system will not load the upgraded kernel module until the new public key is enrolled.

Use the Unified Extensible Firmware Interface (UEFI) Secure Boot feature to enroll the public key. If you are protecting VMware virtual machines, the Secure Boot feature is available for VMware vSphere 6.5 or newer. For instructions on how to enable it, see Enable or Disable UEFI Secure Boot for a Virtual Machine on the VMware Docs site.

The Secure Boot feature is not available for AWS instances and Azure VMs.

To enroll the Trend Micro public key:

  1. On the RHEL 7 computer that you want to protect, install the Deep Security Agent, if it isn't installed already.

    After installation, the Trend Micro public key is in /opt/ds_agent/DS12.der.

  2. Install the Machine Owner Key (MOK) facility, if it isn't already installed

    yum install mokutil

  3. Add the public key, DS12.der, to the MOK list:

    mokutil --import DS12.der

    For details about manually adding the public key to the MOK list, see the Red Hat documentation.

  4. When prompted, enter a password that you will use later in this procedure.
  5. Reboot the system.
  6. After the computer restarts, the Shim UEFI key management console opens:
  7. Shim UEFI key management console
  8. Press any key to get started.
  9. On the Perform MOK management screen, select Enroll MOK.
  10. On the Enroll MOK screen, select View key 0.
  11. On the Enroll the key(s)? screen, select Yes and then enter the password you set in step 4, above.
  12. On the The system must now be rebooted screen, select OK to confirm your changes and reboot.
  13. Next, use the keyctl utility to check that key is on the system key ring. If the keyctl utility is not already installed, use this command to install it:

    yum install keyutils

  14. To list the keys that are on the system key ring:

    keyctl list %:.system_keyring

    You should see the Trend Micro signing key listed.