Support modules

LPAR mode z/VM guest KVM guest

Ubuntu Server 20.04.1 LTS automatically loads the modules that support the available hardware-acceleration.

sha1_s390

enables hardware-acceleration for SHA-1 operations. sha1_s390 requires the sha_common module.

sha256_s390

enables hardware-acceleration for SHA-224 and SHA-256 operations. sha256_s390 requires the sha_common module.

sha512_s390

enables hardware-acceleration for SHA-384 and SHA-512 operations. sha512_s390 requires the sha_common module.

sha3_256_s390

enables hardware-acceleration for SHA3-224 and SHA3-256 operations. sha3_256_s390 requires the sha_common module.

sha3_512_s390

enables hardware-acceleration for SHA3-384 and SHA3-512 operations. sha3_512_s390 requires the sha_common module.

ghash_s390

enables hardware-acceleration for Galois hashes.

aes_s390

enables hardware-acceleration for AES encryption and decryption for the following modes of operation:

ECB, CBC, and CTR for key lengths 128, 192, and 256 bits
XTS for key lengths 128 and 256 bits
GCM for key lengths 128, 192, and 256 bits

des_s390

enables hardware-acceleration for DES and TDES for the following modes of operation: ECB, CBC, and CTR.

crc32-vx_s390

enables hardware-acceleration for CRC-32 (IEEE 802.3 Ethernet) and CRC-32C (Castagnoli).

paes_s390

enables protected key AES encryption and decryption for the following modes of operation:

ECB, CBC, and CTR for key lengths 128, 192, and 256 bits
XTS for key lengths 128 and 256 bits

The paes_s390 kernel module includes a self test for each cipher that it provides. These self tests run by default. As a prerequisite for a successful self test, at least one of the following conditions must be met:

The PCKMO instruction is enabled in the profile of the LPAR on which the Linux® instance or its hosting hypervisor runs. To enable the PCKMO instruction, select the Permit AES Key import functions option in the CPACF Key Management Operations section.
The Linux instance can access a cryptographic adapter in CCA coprocessor mode.
The Linux instance can access a cryptographic adapter in EP11 coprocessor mode.

The paes_s390 module requires the pkey device driver, see Protected key device driver.

The module also requires a cryptographic adapter for creating and handling secure and protected keys:

To use CCA AES data or CCA AES cipher secure keys, the module requires a cryptographic adapter in CCA coprocessor mode.
To use EP11 secure keys, the module requires a cryptographic adapter in EP11 coprocessor mode.

The paes_390 module accepts key tokens of different types as key material, as produced by the pkey driver:

Secure key tokens. For secure key tokens, the module needs a CCA cryptographic adapter. For more information about secure key tokens, see Generating secure keys using the pkey device driver
Protected key tokens from random data. No cryptographic adapter is needed. For more information about protected key tokens from random data, see Generating volatile protected keys by using the pkey device driver.

The ciphers in the paes_s390 module can work with CCA secure data keys and CCA secure cipher keys, for example, keys that are generated by the pkey device driver. XTS requires two secure keys.

Before the paes_s390 module uses secure keys in a cipher, it transforms them into protected keys. If a protected key becomes invalid, the paes_s390 module re-generates the protected key from the secure key.

Mainframe hardware prior to z14: To use CPACF for AES-GCM operations, you must load both the aes_s390 and ghash_s390 module.