com.absio.crypto.keyagreement

Class KeyAgreementHelper

java.lang.Object

com.absio.crypto.keyagreement.KeyAgreementHelper

public class KeyAgreementHelper
extends Object

This helper is used to compute the shared secret in a Diffie Hellman key exchange. This is done using the JCE KeyAgreement class. By default KeyAgreementHelper.KeyAgreementAlgorithm.ECDH is used for the algorithm (ECDH).

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	KeyAgreementHelper.KeyAgreementAlgorithm This enumeration represents the key agreement algorithms that Absio knowingly supports.

Constructor Summary

Constructors

Constructor and Description
KeyAgreementHelper() Create the helper with KeyAgreementHelper.KeyAgreementAlgorithm.ECDH.
KeyAgreementHelper(KeyAgreementHelper.KeyAgreementAlgorithm algorithm) Create the helper with the given KeyAgreementHelper.KeyAgreementAlgorithm.

Method Summary

Modifier and Type	Method and Description
byte[]	generateSharedSecret(PrivateKey privateKey, PublicKey publicKey) Generate the Diffie Hellman shared secret with the given private and public keys.

Methods inherited from class java.lang.Object

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

Constructor Detail

KeyAgreementHelper

public KeyAgreementHelper()
                   throws NoSuchAlgorithmException

Create the helper with KeyAgreementHelper.KeyAgreementAlgorithm.ECDH.

Throws:

NoSuchAlgorithmException - thrown if KeyAgreementHelper.KeyAgreementAlgorithm.ECDH is not supported

KeyAgreementHelper

public KeyAgreementHelper(KeyAgreementHelper.KeyAgreementAlgorithm algorithm)
                   throws NoSuchAlgorithmException

Create the helper with the given KeyAgreementHelper.KeyAgreementAlgorithm.

Parameters:

algorithm - the KeyAgreementHelper.KeyAgreementAlgorithm

Throws:

NoSuchAlgorithmException - thrown if the given KeyAgreementHelper.KeyAgreementAlgorithm is not supported

Method Detail

generateSharedSecret

public byte[] generateSharedSecret(PrivateKey privateKey,
                                   PublicKey publicKey)
                            throws InvalidKeyException

Generate the Diffie Hellman shared secret with the given private and public keys. This uses KeyAgreement with the helper's KeyAgreementHelper.KeyAgreementAlgorithm.

Parameters:

privateKey - the private key

publicKey - the public key

Returns:

the shared secret

Throws:

InvalidKeyException - thrown if either of the keys do match the KeyAgreementHelper.KeyAgreementAlgorithm