org.bouncycastle.jcajce.provider.asymmetric.dh

Class KeyAgreementSpi

java.lang.Object

javax.crypto.KeyAgreementSpi

org.bouncycastle.jcajce.provider.asymmetric.dh.KeyAgreementSpi

public class KeyAgreementSpi
extends KeyAgreementSpi

Diffie-Hellman key agreement. There's actually a better way of doing this if you are using long term public keys, see the light-weight version for details.

Constructor Summary

Constructors

Constructor and Description
KeyAgreementSpi()

Method Summary

Modifier and Type	Method and Description
protected Key	engineDoPhase(Key key, boolean lastPhase) Does the next (or the last) phase of the key agreement, using the specified key.
protected byte[]	engineGenerateSecret() Generates the shared secret.
protected int	engineGenerateSecret(byte[] sharedSecret, int offset) Generates the shared secret and stores it into the buffer sharedSecred at offset.
protected SecretKey	engineGenerateSecret(String algorithm) Generates the shared secret.
protected void	engineInit(Key key, AlgorithmParameterSpec params, SecureRandom random) Initializes this KeyAgreementSpi with the specified key, algorithm parameters and randomness source.
protected void	engineInit(Key key, SecureRandom random) Initializes this KeyAgreementSpi with the specified key and the specified randomness source.

Methods inherited from class java.lang.Object

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

Constructor Detail

KeyAgreementSpi

public KeyAgreementSpi()

Method Detail

engineDoPhase

protected Key engineDoPhase(Key key,
                            boolean lastPhase)
                     throws InvalidKeyException,
                            IllegalStateException

Description copied from class: KeyAgreementSpi

Does the next (or the last) phase of the key agreement, using the specified key.

Specified by:

engineDoPhase in class KeyAgreementSpi

Parameters:

key - the key received from the other party for this phase.

lastPhase - set to true if this is the last phase of this key agreement.

Returns:

the intermediate key from this phase or null if there is no intermediate key for this phase.

Throws:

InvalidKeyException - if the specified key cannot be used in this key agreement or this phase,

IllegalStateException - if this instance has not been initialized.

engineGenerateSecret

protected byte[] engineGenerateSecret()
                               throws IllegalStateException

Description copied from class: KeyAgreementSpi

Generates the shared secret.

Specified by:

engineGenerateSecret in class KeyAgreementSpi

Returns:

the generated shared secret.

Throws:

IllegalStateException - if this key agreement is not complete.

engineGenerateSecret

protected int engineGenerateSecret(byte[] sharedSecret,
                                   int offset)
                            throws IllegalStateException,
                                   ShortBufferException

Description copied from class: KeyAgreementSpi

Generates the shared secret and stores it into the buffer sharedSecred at offset.

Specified by:

engineGenerateSecret in class KeyAgreementSpi

Parameters:

sharedSecret - the buffer to store the shared secret.

offset - the offset in the buffer.

Returns:

the number of bytes stored in the buffer.

Throws:

IllegalStateException - if this key agreement is not complete.

ShortBufferException - if the specified buffer is too small for the shared secret.

engineGenerateSecret

protected SecretKey engineGenerateSecret(String algorithm)

Description copied from class: KeyAgreementSpi

Generates the shared secret.

Specified by:

engineGenerateSecret in class KeyAgreementSpi

Parameters:

algorithm - the algorithm to for the SecretKey

Returns:

the shared secret as a SecretKey of the specified algorithm.

engineInit

protected void engineInit(Key key,
                          AlgorithmParameterSpec params,
                          SecureRandom random)
                   throws InvalidKeyException,
                          InvalidAlgorithmParameterException

Description copied from class: KeyAgreementSpi

Initializes this KeyAgreementSpi with the specified key, algorithm parameters and randomness source.

Specified by:

engineInit in class KeyAgreementSpi

Parameters:

key - the key to initialize this key agreement.

params - the parameters for this key agreement algorithm.

random - the source for any randomness needed.

Throws:

InvalidKeyException - if the specified key cannot be used to initialize this key agreement.

InvalidAlgorithmParameterException - if the specified parameters are invalid for this key agreement algorithm.

engineInit

protected void engineInit(Key key,
                          SecureRandom random)
                   throws InvalidKeyException

Description copied from class: KeyAgreementSpi

Initializes this KeyAgreementSpi with the specified key and the specified randomness source.

Specified by:

engineInit in class KeyAgreementSpi

Parameters:

key - the key to initialize this key agreement.

random - the source for any randomness needed.

Throws:

InvalidKeyException - if the specified key cannot be used to initialize this key agreement.