Driver configurations and supported features

Configuring multiple drivers
AES cipher configuration
- AES cipher driver configuration
MAC configuration
- MAC driver configurations
AEAD configurations
- AEAD driver configurations
ECC configurations
- ECC driver configurations
ECC curve configurations
- ECC curve driver configurations
RSA configurations
- RSA driver configurations
Secure Hash configurations
- Secure Hash driver configurations

This section covers the configurations available when using PSA drivers.

Configuring multiple drivers 

Multiple PSA drivers can be enabled at the same time, with added support for fine-grained control of which drivers implement support for cryptographic features.

To enable a PSA driver, set the configurations according to the following table:

PSA driver \| Configuration option			Notes
nrf_cc3xx \| `CONFIG_PSA_CRYPTO_DRIVER_CC3XX`			Only on nRF52840, nRF9160, and nRF5340 devices
nrf_oberon	`CONFIG_PSA_RYPTO_DRIVER_OBERON`

If multiple drivers are enabled, the first ordered item in this table takes precedence for an enabled cryptographic feature, unless the driver does not enable or support it.

Enabling or disabling PSA driver specific configurations controls the support for a given algorithm, per driver.

If a specific cryptographic feature is not supported by a PSA driver but the algorithm is configured to be used, then Built-in Mbed TLS will be enabled to ensure the feature is available.

AES cipher configuration 

AES cipher modes can be enabled by setting one or more of the following Kconfig options:

Cipher mode	Configuration option
ECB_NO_PADDING	`CONFIG_PSA_WANT_ALG_ECB_NO_PADDING`
CBC_NO_PADDING	`CONFIG_PSA_WANT_ALG_CBC_NO_PADDING`
CBC_PKCS7	`CONFIG_PSA_WANT_ALG_CBC_PKCS7`
CFB	`CONFIG_PSA_WANT_ALG_CFB`
CTR	`CONFIG_PSA_WANT_ALG_CTR`
OFB	`CONFIG_PSA_WANT_ALG_OFB`
XTS	`CONFIG_PSA_WANT_ALG_XTS`

AES cipher driver configuration 

You can use the Kconfig options from the following table for fine-grained control over which drivers provide AES cipher support:

Cipher mode	nrf_cc3xx driver support	nrf_oberon driver support
ECB_NO_PADDING	`CONFIG_PSA_CRYPTO_DRIVER_ALG_ECB_NO_PADDING_CC3XX`	`CONFIG_PSA_CRYPTO_DRIVER_ALG_ECB_NO_PADDING_OBERON`
CBC_NO_PADDING	`CONFIG_PSA_CRYPTO_DRIVER_ALG_CBC_NO_PADDING_CC3XX`	`CONFIG_PSA_CRYPTO_DRIVER_ALG_CBC_NO_PADDING_OBERON`
CBC_PKCS7	`CONFIG_PSA_CRYPTO_DRIVER_ALG_CBC_PKCS7_CC3XX`	Not supported
CFB	`CONFIG_PSA_CRYPTO_DRIVER_ALG_CFB_CC3XX`	Not supported
CTR	`CONFIG_PSA_CRYPTO_DRIVER_ALG_CTR_CC3XX`	`CONFIG_PSA_CRYPTO_DRIVER_ALG_CTR_OBERON`
OFB	Not supported	Not supported
XTS	Not supported	Not supported

Note

If an AES cipher mode is enabled and no PSA driver enables or supports it, then Built-in Mbed TLS support is enabled and used.
The Arm CryptoCell cc3xx driver is limited to AES key sizes of 128 bits on devices with Arm CryptoCell cc310.

MAC configuration 

You can enable MAC support by setting one or more Kconfig options in the following table:

MAC cipher	Configuration option
ECB_NO_PADDING	`CONFIG_PSA_WANT_ALG_CMAC`
CBC_NO_PADDING	`CONFIG_PSA_WANT_ALG_HMAC`

MAC driver configurations 

You can use the Kconfig options in the following table for fine-grained control over which drivers provide AEAD support:

MAC cipher	nrf_cc3xx driver support		nrf_oberon driver support
ECB_NO_PADDING	`CONFIG_PSA_CRYPTO_DRIVER_ALG_CMAC_CC3XX`		Not supported
CBC_NO_PADDING	`CONFIG_PSA_CRYPTO_DRIVER_ALG_HMAC_CC3XX`		Not supported

Note

If a MAC algorithm is enabled and no PSA driver enables or supports it, then Built-in Mbed TLS support is enabled and used.
The Arm CryptoCell cc3xx driver is limited to AES CMAC key sizes of 128 bits on devices with Arm CryptoCell cc310.
The Arm CryptoCell cc3xx driver is limited to HMAC using SHA-1, SHA-224, and SHA-256 on devices with Arm CryptoCell cc310.

AEAD configurations 

You can enable Authenticated Encryption with Associated Data (AEAD) by setting one or more Kconfig options in the following table:

AEAD cipher	Configuration option
AES CCM	`CONFIG_PSA_WANT_ALG_CCM`
AES GCM	`CONFIG_PSA_WANT_ALG_GCM`
ChaCha/Poly	`CONFIG_PSA_WANT_ALG_CHACHA20_POLY1305`

AEAD driver configurations 

You can use the Kconfig options in the following table for fine-grained control over which drivers provide AEAD support:

AEAD cipher	nrf_cc3xx driver support	nrf_oberon driver support
AES CCM	`CONFIG_PSA_CRYPTO_DRIVER_ALG_CCM_CC3XX`	`CONFIG_PSA_CRYPTO_DRIVER_ALG_CCM_OBERON`
AES GCM	`CONFIG_PSA_CRYPTO_DRIVER_ALG_GCM_CC3XX`	Not Supported
ChaCha/Poly	`CONFIG_PSA_CRYPTO_DRIVER_ALG_CHACHA20_POLY1305_CC3XX`	`CONFIG_PSA_CRYPTO_DRIVER_ALG_CHACHA20_POLY1305_OBERON`

Note

If an AEAD algorithm is enabled and no PSA driver enables or supports it, then Built-in Mbed TLS support is enabled and used.
The Arm CryptoCell cc3xx driver is limited to AES key sizes of 128 bits on devices with Arm CryptoCell cc310.
The Arm CryptoCell cc3xx driver does not provide hardware support for AES GCM on devices with Arm CryptoCell cc310.

ECC configurations 

You can enable Elliptic Curve Cryptography (ECC) by setting one or more Kconfig options in the following table:

ECC algorithm		Configuration option
ECDH \| `CONFIG_PSA_WANT_ALG_ECDH`
ECDSA \| `CONFIG_PSA_WANT_ALG_ECDSA`
ECDSA (deterministic)		`CONFIG_PSA_WANT_ALG_DETERMINISTIC_ECDSA`

The ECC algorithm support is dependent on one or more Kconfig options enabling curve support according to ECC curve configurations.

ECC driver configurations 

You can use the Kconfig options in the following table for fine-grained control over which drivers provide ECC support:

ECC algorithm	nrf_cc3xx driver support	nrf_oberon driver support
ECDH \| `CONFIG_PSA_CRYPTO_DRIVER_ALG_ECDH_CC3XX`		`CONFIG_PSA_CRYPTO_DRIVER_ALG_ECDSA_OBERON`
ECDSA \| `CONFIG_PSA_CRYPTO_DRIVER_ALG_ECDSA_CC3XX`		`CONFIG_PSA_CRYPTO_DRIVER_ALG_ECDSA_OBERON`
ECDSA (deterministic)	`CONFIG_PSA_CRYPTO_DRIVER_ALG_DETERMINISTIC_ECDSA_CC3XX`	`CONFIG_PSA_CRYPTO_DRIVER_ALG_DETERMINISTIC_ECDSA_OBERON`

Note

If an ECC algorithm is enabled and no PSA driver enables or supports it, then Built-in Mbed TLS support is enabled and used.
The nrf_oberon driver is currently limited to curve types secp224r1 and secp256r1 for ECDH and ECDSA.

ECC curve configurations 

You can configure elliptic curve support by setting one or more Kconfig options in the following table:

ECC curve type	Configuration option
Brainpool256r1	`CONFIG_PSA_WANT_ECC_BRAINPOOL_P_R1_256`
Brainpool384r1	`CONFIG_PSA_WANT_ECC_BRAINPOOL_P_R1_384`
Brainpool512r1	`CONFIG_PSA_WANT_ECC_BRAINPOOL_P_R1_512`
Curve25519	`CONFIG_PSA_WANT_ECC_MONTGOMERY_255`
Curve448	`CONFIG_PSA_WANT_ECC_MONTGOMERY_448`
secp192k1	`CONFIG_PSA_WANT_ECC_SECP_K1_192`
secp256k1	`CONFIG_PSA_WANT_ECC_SECP_K1_256`
secp192r1	`CONFIG_PSA_WANT_ECC_SECP_R1_192`
secp224r1	`CONFIG_PSA_WANT_ECC_SECP_R1_224`
secp256r1	`CONFIG_PSA_WANT_ECC_SECP_R1_256`
secp384r1	`CONFIG_PSA_WANT_ECC_SECP_R1_384`
secp521r1	`CONFIG_PSA_WANT_ECC_SECP_R1_521`

ECC curve driver configurations 

You can sue the Kconfig options in the following table for fine-grained control over which drivers provide elliptic curve support:

ECC curve type	nrf_cc3xx driver support	nrf_oberon driver support
Brainpool256r1	`CONFIG_PSA_CRYPTO_DRIVER_ECC_BRAINPOOL_P_R1_256_CC3XX`	Not supported
Brainpool384r1	Not supported	Not supported
Brainpool512r1	Not supported	Not supported
Curve25519	`CONFIG_PSA_CRYPTO_DRIVER_ECC_MONTGOMERY_255_CC3XX`	`CONFIG_PSA_CRYPTO_DRIVER_ECC_MONTGOMERY_255_OBERON`
Curve448	Not supported	Not supported
secp192k1	`CONFIG_PSA_CRYPTO_DRIVER_ECC_SECP_K1_192_CC3XX`	Not supported
secp256k1	`CONFIG_PSA_CRYPTO_DRIVER_ECC_SECP_K1_256_CC3XX`	Not supported
secp192r1	`CONFIG_PSA_CRYPTO_DRIVER_ECC_SECP_R1_192_CC3XX`	Not supported
secp224r1	`CONFIG_PSA_CRYPTO_DRIVER_ECC_SECP_R1_224_CC3XX`	`CONFIG_PSA_CRYPTO_DRIVER_ECC_SECP_R1_224_OBERON`
secp256r1	`CONFIG_PSA_CRYPTO_DRIVER_ECC_SECP_R1_256_CC3XX`	`CONFIG_PSA_CRYPTO_DRIVER_ECC_SECP_R1_256_OBERON`
secp384r1	`CONFIG_PSA_CRYPTO_DRIVER_ECC_SECP_R1_384_CC3XX`	Not supported
secp521r1	`CONFIG_PSA_CRYPTO_DRIVER_ECC_SECP_R1_521_CC3XX`	Not supported

RSA configurations 

You can enable Rivest-Shamir-Adleman (RSA) support by setting one or more Kconfig options in the following table:

RSA algorithms	Configuration option
RSA OAEP	`CONFIG_PSA_WANT_ALG_RSA_OAEP`
RSA PKCS#1 v1.5 crypt	`CONFIG_PSA_WANT_ALG_RSA_PKCS1V15_CRYPT`
RSA PKCS#1 v1.5 sign	`CONFIG_PSA_WANT_ALG_RSA_PKCS1V15_SIGN`
RSA PSS	`CONFIG_PSA_WANT_ALG_RSA_PSS`

RSA driver configurations 

You can use the Kconfig options in the following table for fine-grained control over which drivers provide RSA support:

RSA algorithms	nrf_cc3xx driver support	nrf_oberon driver support
RSA OAEP	`CONFIG_PSA_CRYPTO_DRIVER_ALG_RSA_OAEP_CC3XX`	Not supported
RSA PKCS#1 v1.5 crypt	`CONFIG_PSA_CRYPTO_DRIVER_ALG_RSA_PKCS1V15_CRYPT_CC3XX`	Not supported
RSA PKCS#1 v1.5 sign	`CONFIG_PSA_CRYPTO_DRIVER_ALG_RSA_PKCS1V15_SIGN_CC3XX`	Not supported
RSA PSS	`CONFIG_PSA_CRYPTO_DRIVER_ALG_RSA_PSS_CC3XX`	Not supported

Note

If an RSA algorithm is enabled and no PSA driver enables or supports it, then Built-in Mbed TLS support is enabled and used.
Arm CryptoCell cc3xx driver is limited to key sizes of <= 2048 bits.

Secure Hash configurations 

You can configure the Secure Hash algorithms by setting one or more Kconfig options according to the following table:

Hash algorithm	Configuration optio
SHA-1	`CONFIG_PSA_WANT_ALG_SHA_1`
SHA-224	`CONFIG_PSA_WANT_ALG_SHA_224`
SHA-256	`CONFIG_PSA_WANT_ALG_SHA_256`
SHA-384	`CONFIG_PSA_WANT_ALG_SHA_384`
SHA-512	`CONFIG_PSA_WANT_ALG_SHA_512`

Secure Hash driver configurations 

You can use the PSA driver-specific configurations provided in this table for fine-grained control over which drivers provide the Secure Hash algorithm.

Hash algorithm	nrf_cc3xx driver support	nrf_oberon driver support
SHA-1	`CONFIG_PSA_CRYPTO_DRIVER_ALG_SHA_1_CC3XX`	`CONFIG_PSA_CRYPTO_DRIVER_ALG_SHA_1_OBERON`
SHA-224	`CONFIG_PSA_CRYPTO_DRIVER_ALG_SHA_224_CC3XX`	`CONFIG_PSA_CRYPTO_DRIVER_ALG_SHA_224_OBERON`
SHA-256	`CONFIG_PSA_CRYPTO_DRIVER_ALG_SHA_256_CC3XX`	`CONFIG_PSA_CRYPTO_DRIVER_ALG_SHA_256_OBERON`
SHA-384	Not supported	`CONFIG_PSA_CRYPTO_DRIVER_ALG_SHA_384_OBERON`
SHA-512	Not supported	`CONFIG_PSA_CRYPTO_DRIVER_ALG_SHA_512_OBERON`

Note

If Secure Hash algorithm is enabled and no PSA driver enables or supports it, then Built-in Mbed TLS support is enabled and used.