Package io.getlime.security.powerauth.crypto.lib.util

Class KeyDerivationUtils

java.lang.Object

io.getlime.security.powerauth.crypto.lib.util.KeyDerivationUtils

public class KeyDerivationUtils
extends Object

The KeyDerivationUtils class provides additional key derivation functionality defined for PowerAuth protocol.

Constructor Summary

Constructors

Constructor	Description
KeyDerivationUtils()

Method Summary

Modifier and Type	Method	Description
byte[]	deriveIvForStatusBlobEncryption(byte[] challenge, byte[] nonce, SecretKey transportKey)	Derive Initialization Vector for AES-CBC cipher used for an activation status blob encryption and decryption.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

KeyDerivationUtils

public KeyDerivationUtils()

Method Details

deriveIvForStatusBlobEncryption

public byte[] deriveIvForStatusBlobEncryption(byte[] challenge,
 byte[] nonce,
 SecretKey transportKey)
                                       throws GenericCryptoException,
CryptoProviderException,
InvalidKeyException

Derive Initialization Vector for AES-CBC cipher used for an activation status blob encryption and decryption. The function also supports older protocol versions (V2, V3), where IV was hard-set to array of zero bytes. In this case, both challenge and nonce parameters must be null.

Note that non-zero IV was introduced in the protocol version 3.1

Parameters:

challenge - Cryptographic challenge received from the client, or generated in the client.

nonce - Cryptographic nonce received from the server, or generated in the server.

transportKey - Transport key.

Returns:

Initialization vector, or zero filled IV when both, challenge and nonce parameters are null.

Throws:

GenericCryptoException - In case that key derivation fails or you provided invalid challenge or nonce.

CryptoProviderException - In case cryptography provider is incorrectly initialized.

InvalidKeyException - In case that transport key is not valid.