Class HkdfKeyDerivationExample

java.lang.Object

net.jrodolfo.java_evolution.java25.key_derivation.HkdfKeyDerivationExample

public class HkdfKeyDerivationExample
extends Object

Demonstrates the Java 25 Key Derivation Function API with HKDF-SHA256.

HKDF is the HMAC-based Key Derivation Function. It takes input key material, an optional salt, and application-specific context information, then derives key bytes for a concrete purpose. This is useful after a key exchange, such as KEM, because raw shared material is usually not the exact key an application should use directly.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	ALGORITHM	Standard algorithm name for HKDF with SHA-256.

Constructor Summary

Constructors

Constructor	Description
HkdfKeyDerivationExample()

Method Summary

Modifier and Type	Method	Description
DerivedKeyMaterial	deriveAes256Key(byte[] inputKeyMaterial, byte[] salt, String contextLabel)	Derives 256-bit key material for a specific application context.

Methods inherited from class Object

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

Field Details

ALGORITHM

public static final String ALGORITHM

Standard algorithm name for HKDF with SHA-256.

See Also:

• Constant Field Values

Constructor Details

HkdfKeyDerivationExample

public HkdfKeyDerivationExample()

Method Details

deriveAes256Key

public DerivedKeyMaterial deriveAes256Key(byte[] inputKeyMaterial,
 byte[] salt,
 String contextLabel)
                                   throws NoSuchAlgorithmException,
InvalidAlgorithmParameterException

Derives 256-bit key material for a specific application context.

Parameters:

inputKeyMaterial - the existing secret material

salt - additional random or protocol-specific salt

contextLabel - purpose-specific context information

Returns:

derived key material

Throws:

NoSuchAlgorithmException - if HKDF-SHA256 is not available

InvalidAlgorithmParameterException - if the HKDF parameters are invalid