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Edition SC34-2782-03
A new feature of the infrastructure for protected volume encryption enhances the paes_s390 and the pkey kernel modules to allow using randomly generated protected keys without requiring a cryptographic coprocessor. This is mainly useful for encrypted swap disks, or any other cases where the keys may be ephemeral, that means, their lifetime does not extend over different boot cycles or machine migrations.
Edition SC34-2782-04
  • The zkey and zkey-cryptsetup tools are enhanced with new functions:
    • During creation of a secure key, or modification of APQNs associated with a certain secure key, the tools perform a cross check whether all associated APQNs have the same master key.
    • The display of the master key register during a zkey validate command for a secure key is enhanced with the output of the master key verification pattern in this register. The master key verification pattern is displayed even when the secure key is no longer valid.
    • PBKDF2 is now automatically used as password based key derivation function for key slots when using secure keys. This avoids out-of-memory errors when using the LUKS2 default Argon2i.
    • A batch-mode option is added to the zkey cryptsetup subcommand and to the zkey-cryptsetup reeincipher subcommand. This option suppresses any user confirmation and thus enables a better automation.
    • Also, to enable a better automation of commands generated by the zkey cryptsetup function, you can specify values for --keyfile-size or --keyfile-offset to control which part of the key file is used as passphrase. These options and values are passed to the generated commands.
    • You can specify the same common passphrase options when generating crypttab entries using the zkey crypttab function.
  • Both the zkey and the zkey-cryptsetup commands are enhanced to support generation and management of CCA AES CIPHER keys. Up to now, only CCA AES DATA keys have been supported. This was transparent for the user. Now you can specify the key type at key generation time.
  • Also, starting with IBM® 4769 Crypto Express7 feature (CEX7S) on IBM z15™, both the zkey and the zkey-cryptsetup commands are enhanced to support generation and management of EP11 AES secure keys for use in CPACF protected key operations.
Edition SC34-2782-05
  • The zkey and zkey-cryptsetup commands now offer support for retrievable secrets on IBM Secure Execution for Linux® guests (IBM SEL guests).
    • With the zkey pvsecret import command, you can import retrievable secrets of type AES and AES-XTS on the IBM SEL guest into the secure key repository (also called zkey key repository) as key blobs with the new key type PVSECRET-AES.
    • With the zkey pvsecret list command, you can list retrievable secrets in the store of secrets in the ultravisor for an IBM SEL guest.

    For details about zkey pvsecret import and zkey pvsecret list, see Handling retrievable secrets of an IBM Secure Execution for Linux guest .

  • You can now use zkey to store a dummy LUKS2 passphrase together with a secure key in the zkey key repository. This dummy passphrase is then used in generated commands to unlock the LUKS2 volume. For more information, read Ease the use of passphrases and Generating a secure key.
  • You can now use the new zkey-cryptsetup convert command to convert a clear-key encrypted LUKS2 volume to a volume encrypted with the PAES cipher using an equivalent secure key blob or retrievable secret key blob. See Converting a LUKS2 volume from encryption with a clear key to a retrievable secret or a secure key.
  • With the zkey utility, you can now generate extractable EP11 AES and exportable AES CIPHER secure keys. Such keys can be securely transported by means of wrapping them with a key encrypting key (KEK).

    In addition, you can now restrict extractable EP11 AES secure keys to be wrapped by trusted KEKs only. These options are only available for recent EP11 versions, and if the corresponding control points are correctly set.

    This enhancement is required if a key generated inside an IBM Secure Execution for Linux guest shall ever be used outside of that guest. For details, read Handling EP11 extractable or CCA exportable keys.

  • In the past, the zkey utility could not process EP11 keys of type EP11-AES if they were session bound keys. In particular, keys generated in an IBM Secure Execution for Linux guest could not be processed, because such keys are implicitly bound to an ultravisor session. With the upstream version 2.30.0 of the s390-tools package, the zkey utility can now process session bound keys of type EP11-AES.
    Note: Use the zkey cryptsetup commands to have cryptsetup commands generated that reference the keys. This ensures that the key sizes are correctly calculated.
  • Argon2i is now used as the default password based key derivation function in option pbkdf of the zkey cryptsetup command. To avoid out-of-memory conditions, moderate values for the arguments for Argon2i are configured by zkey cryptsetup for restricting memory and time resources, because using the default Argon2i options might still cause out-of-memory errors.